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8070661 | A reevaluation of data from competitive tests shows high levels of heterosis in Drosophila melanogaster. | We have analyzed the results from a range of procedures designed to measure the fitness petitive conditions of inbred strains of Drosophila melanogaster, specifically strains which are homozygous for chromosome 2. All methods show a substantial reduction in fitness, ranging from an estimated 70-80% for single petition tests to 80-90% for a multiple generation population cage procedure. Furthermore, inbreeding through brother-sister mating reduces fitness by parable amount when allowance is made for the expected degree of homozygosity. |
8070662 | A Drosophila third chromosome Minute locus encodes a ribosomal protein. | Minutes (M) are a group of over 50 phenotypically similar Drosophila mutations widely believed to affect ribosomal protein genes. This report describes the characterization of the P element-induced M(3)95A(Plac92) mutation [allelic to M(3)95A]. This mutation can be reversed by the mobilization of the P element, demonstrating that the mutation is caused by insertion of this transposable element. The gene interrupted by insertion of the P element was cloned by use of inverse polymerase chain reaction. Nucleotide sequence analysis revealed a 70-75% identity to the human and rat ribosomal protein S3 genes, and to the Xenopus ribosomal protein S1a gene. At the amino acid level, the overall identity is approximately 78% for all three species. This is only the second time that a Minute has been demonstrated to encode a ribosomal protein. |
8070664 | Molecular analysis of the Drosophila EGF receptor homolog reveals that several genetically defined classes of alleles cluster in subdomains of the receptor protein. | Mutations in the torpedo gene, which encodes the fruitfly homolog of the epidermal growth factor receptor (DER), disrupt a variety of developmental processes in Drosophila. These include the survival of certain embryonic ectodermal tissues, the proliferation of the imaginal discs, the morphogenesis of several adult ectodermal structures and oogenesis, torpedo is plex: a number of alleles of the gene differentially affect the development of specific tissues, such as the eye, wing, bristles and ovary. In addition, torpedo mutations exhibit plementation. Molecular analysis of 24 loss-of-function mutations in the torpedo gene provides insights into the mechanistic basis of its plexity. We observe an intriguing correlation between molecular lesions and mutant phenotypes. Alleles that differentially affect specific developmental processes encode receptors with altered extracellular domains. Alleles that fully or plement a wide range of embryonic and postembryonic torpedo mutations encode receptors with altered intracellular domains. From these findings we conclude the following. First, the torpedo protein may be activated by tissue-specific ligands. Second, the torpedo receptor tyrosine kinase may phosphorylate multiple substrates. Third, signal transduction by torpedo appears to require the physical association of receptors. Finally, the extracellular domain of the Torpedo protein may play an essential role in mediating receptor-receptor interactions. |
8070663 | Components acting in localization of bicoid mRNA are conserved among Drosophila species. | Substantial insights into basic strategies for embryonic body patterning have been obtained from genetic analyses of Drosophila melanogaster. This knowledge has been used in parisons to ask if genes and functions are conserved. To begin to ask how highly conserved are the mechanisms of mRNA localization, a process crucial to Drosophila body patterning, we have focused on the localization of bcd mRNA to the anterior pole of the embryo. Here we consider ponents involved in that process: the exuperantia (exu) gene, required for an early step in localization; and the cis-acting signal that directs bcd mRNA localization. First, we use the cloned D. melanogaster exu gene to identify the exu genes from Drosophila virilis and Drosophila pseudoobscura and to isolate them parisons at the structural and functional levels. Surprisingly, D. pseudoobscura has two closely related exu genes, while D. melanogaster and D. virilis have only one each. When expressed in D. melanogaster ovaries, the D. virilis exu gene and one of the D. pseudoobscura exu genes can substitute for the endogenous exu gene in supporting localization of bcd mRNA, demonstrating that function is conserved. Second, we reevaluate the ability of the D. pseudoobscura bcd mRNA localization signal to function in D. melanogaster. In contrast to a previous report, we find that function is retained. Thus, among these Drosophila species there is substantial conservation ponents acting in mRNA localization, and presumably the mechanisms underlying this process. |
8070665 | Local transposition of P elements in Drosophila melanogaster and recombination between duplicated elements using a site-specific recombinase. | The transposase source delta 2-3(99B) was used to mobilize a P element located at sites on chromosomes X, 2 and 3. The transposition event most frequently recovered was a chromosome with two copies of the P element at or near the original site of insertion. These were easily recognized because the P element carried a hypomorphic white gene with a dosage dependent phenotype; flies with two copies of the gene have darker eyes than flies with one copy. The P element also carried direct repeats of the bination target (FRT) for the FLP site-specific binase. The synthesis of FLP in these flies caused excision of the FRT-flanked white gene. Because the two white copies excised independently, patches of eye tissue with different levels of pigmentation were produced. Thus, the presence of two copies of the FRT-flanked white gene could be verified. When the P elements lay in the same orientation, FLP-mediated bination between the FRTs on separated elements produced deficiencies and duplications of the flanked region. When P elements were inverted, the predominant consequence of FLP-catalyzed bination between the inverted elements was the formation of dicentric chromosomes and acentric fragments as a result of unequal sister chromatid exchange. |
8070666 | Shared sequence variants of Mus spretus LINE-1 elements tracing dispersal to within the last 1 million years. | LINE-1 repetitive sequences contain a record of an evolving population of transposons within the mammalian genome. Of the 100,000 copies of LINE-1 sequences per genome there are many shared sequence variants representing changes occurring within the propagating LINE-1 elements themselves, rather than changes that occur during retrotransposition or after an element inserts in the genome. These shared sequence variants define families of LINE-1 elements which have spread within specific periods of time. We have been interested in studying events in LINE-1 evolution since the speciation of Mus spretus and Mus domesticus approximately 3 million years (Myr) ago. To do this, we have collected LINE-1 sequences that have shared sequence variants specific to M. spretus. The sampled LINE-1 elements were sequenced at their extreme 3' ends, where the density of sequence variants is highest. The new sequences define six new M. spretus-specific sequence variants. Of these, we have found one that could be used to screen for LINE-1 elements arising in the last 1 Myr, which we argue is a critical sample for understanding the dynamics of LINE-1 propagation. |
8070667 | Sheep linkage mapping: nineteen linkage groups derived from the analysis of paternal half-sib families. | Nineteen linkage groups containing a total of 52 markers have been identified in the sheep genome after typing large paternal half-sib families. The linkage groups range in size from 2 markers showing no bination to a group containing 6 markers covering approximately 30 cM of the sheep genome. Thirteen of the groups have been assigned to a sheep chromosome. Three groups contain markers from bovine syntenic groups U2, U7 and U29, and one other group contains a marker that has been mapped only in humans. The remaining three groups are unassigned. This information will provide a useful foundation for a genetic linkage map of sheep. |
8070669 | A ruby in the rubbish: beneficial mutations, deleterious mutations and the evolution of sex. | This study presents a mathematical model in which a single beneficial mutation arises in a very large population that is subject to frequent deleterious mutations. The results suggest that, if the population is sexual, then the deleterious mutations will have little effect on the ultimate fate of the beneficial mutation. However, if most offspring are produced asexually, then the probability that the beneficial mutation will be lost from the population may be greatly enhanced by the deleterious mutations. Thus, sexual populations may adapt much more quickly than populations where most reproduction is asexual. Some of the results were produced puter simulation methods, and a technique was developed that allows treatment of arbitrarily large numbers of individuals in a reasonable amount puter time. This technique may be of prove useful for the analysis of a wide variety of models, though there are some constraints on its applicability. For example, the technique requires that reproduction can be described by Poisson processes. |
8070670 | Oxidative stress-induced apoptosis prevented by Trolox. | The ability of oxidative stress to induce apoptosis (programmed cell death), and the effect of Trolox, a water soluble vitamin E analog, on this induction were studied in vitro in mouse thymocytes. Cells were exposed to oxidative stress by treating them with 0.5-10 microM hydrogen peroxide (H2O2) for 10 min, in phosphate-buffered saline supplemented with 0.1 mM ferrous sulfate. Cells were resuspended in RPMI 1640 medium with 10% serum and incubated at 37 degrees C under 5% CO2 in air. Electron microscopic studies revealed morphological changes characteristic of apoptosis in H2O2-treated cells. H2O2 treatment fragmented the DNA in a manner typical of apoptotic cells, producing a ladder pattern of 200 base pair increments upon agarose gel electrophoresis. The percentage of DNA fragmentation (determined fluorometrically) increased with increasing doses of H2O2 and postexposure incubation times. Pre- or posttreatment of cells with Trolox reduced H2O2-induced DNA fragmentation to control levels and below. The results indicate that oxidative stress induces apoptosis in thymocytes, and this induction can be prevented by Trolox, a powerful inhibitor of membrane damage. |
8070673 | Membrane changes associated with lysis of red blood cells by hypochlorous acid. | This study was carried out to investigate HOCl-induced lysis of human erythrocytes. Using reagent HOCl with isolated red cells, we showed that the rate of lysis was dependent on the dose of HOCl per red cell rather than on the concentration of oxidant. The process was inhibited by scavengers such as methionine and taurine, but only if they were present at the time of addition of HOCl. Lysis was preceded by a decrease in cell density, a change in the deformability of the membrane as evidenced by ektacytometry, and an increase in K(+)-leak. Electron microscopy showed extensive disruption of the membrane. Increasing doses of HOCl caused progressive loss of membrane thiols, plete thiol oxidation by N-ethylmaleimide did not result in an equivalent rate of lysis. Restoration of oxidised thiols by incubation with glucose did not significantly alter the pattern of lysis. Taken together, these results suggest that thiol oxidation was not responsible for HOCl-mediated lysis. There was evidence of increasing crosslinking of membrane proteins on electrophoresis, only some of which was due to the formation of disulfides. TLC of the membrane lipids indicated that there may be formation of chlorohydrins by reaction of HOCl with the fatty acid double bonds. This reaction results in the formation of a more polar species which, if formed, would be extremely disrupting to the lipid bilayer. The results indicate that HOCl-mediated damage to the membrane proteins or to the lipid prises an initial damaging event that sets the cells on a path toward eventual lysis. |
8070668 | The robustness of recombination frequency estimates in intercrosses with dominant markers. | The robustness of the maximum likelihood estimates of bination frequencies has been investigated in double intercrosses plete dominance at both loci. The robustness was investigated with respect to bias in the bination frequency estimates due to: (1) limited sample sizes, (2) heterogeneity in bination frequencies between sexes or among meioses and (3) factors that distort the segregation-misclassification or differential viability. In the coupling phase, the bination frequency estimates are quite robust with respect to most of the investigated factors. Potentially, the most serious cause of a bias is misclassifications, which tend to increase the bination frequency estimates. In the repulsion phase, misclassifications are particularly serious, leading to extreme discrepancies between true and observed values. In addition, limited sample size and sex differences in bination can also bias bination frequency estimates in repulsion. These effects may pose serious problem in genetic mapping with random amplified polymorphic DNA (RAPD) markers. |
8070676 | Ferrous ion formation by ferrioxamine prepared from aged desferrioxamine: a potential prooxidant property. | The siderophore desferrioxamine (DEFOM) binds ferric ions in a 1:1 ratio resulting in a ferrioxamine plex. When DEFOM is stored or heat degraded, the resulting FOMD undergoes an autoreduction with the transfer of electrons to the bound ferric ions forming ferrous ions which react with Ferrozine to yield a plex absorbing at 562 nm. Heat-aged DEFOM forms a plex with an absorption maxima changing from 432 nm to 441 nm. When the autoreduced plex is placed in a phosphate buffer at pH 7.4, ferrous ions autoxidise transferring electrons to molecular oxygen to form superoxide and hydrogen peroxide. Fenton chemistry leading to the formation of hydroxyl radicals can then occur. Studies with a variety of reactive oxygen scavengers support a role for the hydroxyl radical in damage to the detector molecule deoxyribose. However, when EDTA is present, damage to deoxyribose is decreased and the radicals causing deoxyribose degradation no longer appear to be characteristic of the hydroxyl radical. |
8070672 | Tyrosine attack by free radicals derived from catalytic decomposition of carbon tetrachloride. | The interaction between free radicals derived from the catalytic position of carbon tetrachloride and tyrosine (the N-acetyl tyrosine ethyl ester, ATEE) under anaerobic and aerobic conditions was studied. The structure of the reaction products formed was deciphered by the GLC/MS analysis of their trimethylsilyl derivatives. Under anaerobic conditions the formation of the following products was found: (1) an unsaturated derivative of the amino acid; (2) the trimethylsilyl derivative of N-acetyl chloro tyrosine ethyl ester; (3) a hydroxyl adduct of ATEE; (4) an ATEE adduct having a chlorine and a CCl3 group in the molecule (it is suggested that CCl3 is attached to the benzyl carbon and the chlorine located in the benzene ring); (5) an ATEE adduct having only a CCl3 group tentatively assigned to be located on the benzyl carbon; and (6) and (7) were found to be two isomers of an ATEE having one CCl3 on the aromatic ring. Under aerobic conditions the following reaction products were identified: Two products which were similar to those numbered (1) and (2) and formed anaerobically; (8) and (11) two isomeric dichlorinated adducts of ATEE; (9) and (10) two isomeric dichlorinated monohydroxylated derivatives of ATEE. Concerning the potential relevance of these findings, we consider that if similar interactions to those here reported occurred during CCl4 poisoning, the activity of enzymes having tyrosine in their active center might result in impairment. Further, enzymes operating on tyrosine moieties in proteins might be perturbed in their action tyrosine groups were attacked by the free radicals arising from catalytic position of CCl4 evidenced here. |
8070674 | Magnesium-deficiency potentiates free radical production associated with postischemic injury to rat hearts: vitamin E affords protection. | Preexisting magnesium deficiency may alter the susceptibility of rat hearts to postischemic oxidative injury (free radicals). This was examined in rats maintained for 3 weeks on a magnesium-deficient (Mg-D) diet with or without concurrent vitamin E treatment (1.2 mg/day, SC). Magnesium-sufficient (Mg-S) rats received the same diet supplemented with 100 mmol Mg/kg feed. Following sacrifice, isolated working hearts were subjected to 30-, 40-, or 60-min global ischemia and 30-min reperfusion. Postischemic production of free radicals was monitored using electron spin resonance (ESR) spectroscopy and spin trapping with alpha-phenyl-N-tert butylnitrone (PBN, 3 mM final); preischemic and postischemic effluent samples were collected and then extracted with toluene. PBN/alkoxyl adduct(s) (PBN/RO.; alpha H = 1.93 G, alpha N = 13.63 G) were the dominant signals detected in untreated Mg-S and Mg-D postischemic hearts, parably higher signal intensities observed for the Mg-D group following any ischemic duration. Time courses of postischemic PBN/RO. detection were biphasic for both groups (maxima: 2-4 and 8.5-12.5 min), and linear relationships between the extent of PBN/RO. production and the severity of both mechanical dysfunction and tissue injury were determined. Following each duration of ischemia, Mg-D hearts displayed greater levels of total PBN adduct production (1.7-2.0 times higher) and lower recovery of cardiac function (42-48% less) than Mg-S hearts. Pretreating Mg-D rats with vitamin E prior to imposing 40-min ischemia/reperfusion, led to a 49% reduction in total PBN/RO. production, a 55% lower LDH release and a 2.2-fold improvement in functional pared to untreated Mg-D hearts. These data suggest that magnesium deficiency predisposes postischemic hearts to enhanced oxidative injury and functional loss, and that antioxidants may offer significant protection against the pro-oxidant influence(s) of magnesium deficiency. |
8070678 | A comparative study of EPR spin trapping and cytochrome c reduction techniques for the measurement of superoxide anions. | Superoxide anions (O2.-) generated by the reaction of xanthine with xanthine oxidase were measured by the reduction of cytochrome c and by electron paramagnetic resonance (EPR) spectroscopy using the spin trap 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). Studies were performed to determine the relative sensitivities of these two techniques for the measurement of O2.-. Mixtures of xanthine, xanthine oxidase, and DMPO generated two adducts, a transient DMPO-OOH and a smaller but longer-lived DMPO-OH. Both adducts were inhibited by superoxide dismutase (SOD), demonstrating they originated from O2.-, and were also significantly decreased when the experiments were performed using unchelated buffers, suggesting that metal ion impurities in unchelated buffers alter the formation or degradation of DMPO-adducts. O2.-, generated by concentrations of xanthine as low as 0.05 microM, were detectable using EPR spin trapping. In contrast, mixtures of xanthine, xanthine oxidase, and cytochrome c measured spectrophotometrically at 550 nm demonstrated that concentrations of xanthine above 1 microM were required to produce measurable levels of reduced cytochrome c. These studies demonstrate that spin trapping using DMPO was at least 20-fold more sensitive than the reduction of cytochrome c for the measurement of superoxide anions. However, at levels of superoxide generation where cytochrome c provides a linear measurement of production, EPR spin trapping may underestimate radical production, probably due to degradation of DMPO radical adducts. |
8070679 | Lipid peroxidation as molecular mechanism of liver cell injury during reperfusion after ischemia. | The pathophysiological importance of reactive oxygen species has been extensively documented in the pathogenesis of hepatic ischemia-reperfusion injury. Kupffer cells and neutrophils were identified as the dominant sources of the postischemic oxidant stress. To test the hypothesis that a direct free radical-mediated injury mechanism (lipid peroxidation; LPO) may be involved in the pathogenesis, highly sensitive and specific parameters of LPO, i.e., hydroxy-eicosatetraenoic acids (HETES), and F2-isoprostanes, were determined by gas chromatographic-mass spectrometric analysis in liver tissue and plasma during 45 min of hepatic ischemia and up to 24 h of reperfusion. A significant 60-250% increase of F2-isoprostane levels in plasma was found at all times during reperfusion; the HETE content increased only significantly at 1 h of reperfusion and in severely necrotic liver tissue at 24 h with increases between 90-320%. On the other hand, in a model of LPO-induced liver injury (infusion of 0.8 mumol tert-butylhydroperoxide/min/g liver), the hepatic HETE content increased two to fourfold over baseline values at 45 min, i.e., before liver injury. A further increase to 12- to 30-fold of baseline was observed during moderate liver injury. Based on these parisons of LPO and liver injury, it seems highly unlikely that LPO is the primary mechanism of parenchymal cell injury during reperfusion, although it cannot be excluded that LPO may be important as a damaging mechanism in a partment of the liver, e.g., endothelial cells, close to the sources of reactive oxygen, e.g., Kupffer cells and neutrophils. |
8070671 | alpha-Phenyl-tert-butyl-nitrone inhibits free radical release in brain concussion. | Traumatic brain injury (TBI) is one of the important causes of mortality and morbidity. The pathogenesis of the underlying brain dysfunction is poorly understood. Recent data have suggested that oxygen free radicals play a key role in the primary and secondary processes of acute TBI. We report direct electron spin resonance (ESR) evidence of hydroxyl (.OH) radical generation in closed-head injury of rats. Moderate brain concussion was produced by controlled and reproducible mechanical, fixed, closed-head injury. A cortical cup was placed over one cerebral hemisphere within 20 min of the concussion, perfused with artificial cerebrospinal fluid (aCSF) containing the spin trap agent pyridyl-N-oxide-tert-butyl nitrone (POBN, 100 mM), and superfusate samples collected at 10 min intervals for a duration up to 130 min post brain trauma. In addition, POBN was administered systemically (50 mg/kg body wt.) 10 min pretrauma and 20 min posttrauma to improve our ability to detect free radicals. ESR analysis of the superfusate samples revealed six line spectra (alpha N = 15.4 G and alpha beta H = 2.5 G) characteristic of POBN-OH radical adducts, the intensity of which peaked 40 min posttrauma. The signal was undetectable after 120 min. Administration of alpha-phenyl-tert-butyl-nitrone (PBN), a spin adduct forming agent systemically (100 mg/kg body wt. IP 10 min prior to concussion) alone or along with topical PBN (100 mM PBN in aCSF), significantly (p < 0.001) attenuated the ESR signal, suggesting its possible role in the treatment of TBI. |
8070680 | Oxidant-sensitive protein phosphorylation in endothelial cells. | Reactive oxygen is an important regulator of vascular cell biology; however, the mechanisms involved in transducing signals from oxidants in endothelial cells are poorly defined. Because protein phosphorylation is a major mechanism for signal transduction, cultured aortic endothelial cells were exposed to nonlethal concentrations of H2O2 to examine oxidant-sensitive changes in phosphorylation state. Addition of H2O2 increases the phosphorylation of the heat shock protein 27 (HSP27) within 2 min. This response is maximal by 20 min and remains constant for more than 45 min. Levels of intracellular free Ca2+ in endothelial cells did not change following addition of 100 microM H2O2, nor did the ability of the cells to respond to bradykinin. H2O2-induced phosphorylations were either not affected or were slightly increased in cells pretreated with PKC inhibitors (H-8, staurosporin, or calphostin c). Two-dimensional analysis of phosphoproteins from homogenates of 32P-labeled cells revealed that phorbol myristate acetate (PMA) did not cause the same degree of HSP27 phosphorylation as H2O2. Simultaneous addition of 10 eta M PMA and 50 microM H2O2 decreased the oxidant-stimulated phosphorylation of the most acidic HSP27 isoform. These data suggest that signal transduction for H2O2-sensitive endothelial cell responses are not only independent of PKC, but may also be suppressed by the action of the kinase. |
8070677 | In vitro modulation of antioxidant enzyme levels in normal hamster kidney and estrogen-induced hamster kidney tumor. | Antioxidant enzyme (AE) activities were studied in normal hamster kidney proximal tubules and in estrogen-induced hamster kidney cancer. In vivo, kidney tumor had lower activities of manganese superoxide dismutase (MnSOD), copper, zinc superoxide dismutase, catalase, and glutathione peroxidase than kidney proximal tubules. Differences in AE activities were, in general, maintained in tissue culture, with AE activities remaining low in tumor pared to normal cells. Normal proximal tubular cells showed significant induction of MnSOD activity as a function of time in culture or following exposure to diethylstilbestrol, a synthetic estrogen, while MnSOD activity remained low in tumor cells under these conditions. Our results suggest that antioxidant enzymes, particularly MnSOD, are regulated differently in estrogen-induced hamster kidney tumor cells than in normal kidney proximal tubular cells, demonstrating that cancers arising from hormonal influence have similar AE profiles to those previously described in cancers arising from viral or chemical etiologies. |
8070675 | Comparative toxicity of alkyl-1,4-naphthoquinones in rats: relationship to free radical production in vitro. | 2-Methyl-1,4-naphthoquinone causes haemolysis in vivo. This toxic effect is believed to result from oxidative damage to erythrocytes by "active oxygen" species formed via one-electron reduction of the naphthoquinone by oxyhaemoglobin. In the present investigation, seven 2-alkyl-1,4-naphtoquinones have been studied with regard to their haemolytic activity in rats, their ability to cause oxidative damage in erythrocytes in vitro, and their reactivity toward oxyhaemoglobin. A close correlation was observed between the in vivo and in vitro parameters, suggesting that the proposed mechanism of toxicity of 2-methyl-1,4-naphthoquinone is correct and is also applicable to other alkylnaphthoquinones. |
8070681 | Membrane peroxidation: inhibiting effects of water-soluble antioxidants on phospholipids of different charge types. | Quantitative kinetic methods of autoxidation are used to determine the antioxidant activities of two water-soluble antioxidatants of the chromanol type, 6-hydroxy-2,5,7, 8-tetramethylchroman-2-carboxylic acid (Trolox) and 6-hydroxy-2,5,7,8- tetramethyl-2-N,N,N-trimethylethanaminium methylbenzene-sulfonate (MDL 73404), during free radical peroxidation of phospholipid membranes of different charge types. The stoichiometric factor (n) for peroxyl radical trapping for both Trolox and MDL 73404 was found to be 2. Trolox was found to partition partially, approximately 20%, into the lipid phase of liposomes. The antioxidant activity of Trolox during peroxidation of membranes determined by measurements of the absolute rate constant for inhibition of oxygen uptake, kinh, was found to vary with the membrane surface charge that is controlled by variation in pH. When peroxidation is initiated in the lipid phase by azo-bis-2,4- dimethylvaleronitrile (ADVN), using a typical zwitterionic liposome, dilinoleoylphosphatidyl choline (DLPC), the kinh was found to be 2.98 X 10(3) M-1s-1. The kinh of Trolox increased approximately 2-fold for membranes that have a positive surface, including DLPC at pH 4, DLPC containing stearylamine at pH 7, and for a membrane of dimyristoylphosphatidyl acid containing linoleic acid (DMPA/LA). Conversely, Trolox does not inhibit peroxidation of negatively charged dilinoleoylphosphatidyl glycerol (DLPG) at pH 7-11. Studies made of the positively charged MDL 73404 show that its antioxidant activity using DLPC and DLPG is pH dependent. Trolox inhibits the peroxidations of DLPC initiated in the aqueous phase by azo-bis-(2-amidinopropane-HCl)(ABAP) at pH 4 or 7. However, Trolox does not inhibit the peroxidation of DLPG at pH 7. The different antioxidant activities of Trolox and MDL 73404 are rationalized in terms of a peroxyl-radical diffusion model and specific charge interactions between antioxidants and membrane surface. |
8070682 | Effects of natural antioxidant ginkgo biloba extract (EGB 761) on myocardial ischemia-reperfusion injury. | Recently, it was reported that Ginkgo biloba extract (EGb 761), which is known to have antioxidant properties, also has antiarrhythmic effects on cardiac reperfusion-induced arrhythmias. In the present study, effects of EGb 761 on cardiac ischemia-reperfusion injury were investigated from the point of view of recovery of mechanical function as well as the endogenous antioxidant status of ascorbate. Isolated rat hearts were perfused using the Langendorff technique, and 40 min of global ischemia were followed by 20 min of reperfusion. EGb 761 improved cardiac mechanical recovery and suppressed the leakage of lactate dehydrogenase (LDH) during reperfusion. Furthermore, EGb 761 diminished the decrease of myocardial ascorbate content after 40 min of ischemia and 20 min of reperfusion. Interestingly, EGb 761 also suppressed the increase of dehydroascorbate. These results indicate that EGb 761 protects against cardiac ischemia-reperfusion injury and suggest that the protective effects of EGb 761 depend on its antioxidant properties. |
8070684 | A pulse radiolysis study of one-electron oxidation and .OH radical reaction of a new class of antioxidants: 2,5 dimethylpyrrole--amino acid N-conjugates. | A new class of 2,5 dimethylpyrrole functionalized amino acid and peptide antioxidants has been synthesized. Pulse radiolysis studies have been carried out on pounds to determine their reactivity in one-electron oxidation reactions with Br2- and (SCN)2-, as well as their reactivity toward the water radicals .OH and eaq-. pared to similar reactions with parent amino acids and peptides, both rate constants and transient spectra indicate considerable interaction between the electronic states of the pyrrole moiety and amino acid or peptide. parison data is available, radical reactions are significantly more rapid with these derivatives than with the pounds. Exceptions occur in some cases of .OH attack where steric hindrance may be evoked to explain a lower rate constant in the pounds. Electron attachment rates are also found to be enhanced by the presence of the pyrrole ring. |
8070683 | The increase in vasomotor tone induced by a parenteral lipid emulsion is linked to an inhibition of prostacyclin production. | The aim of the study was to verify whether the infusion of a lipid emulsion causes a rise in vascular pressure related to an imbalance in the production of vasoconstricting and vasodilatating eicosanoids. Segments of umbilical veins were perfused with and without 1.5 microM indomethacin (cyclooxygenase inhibitor) in solutions differing only in their lipid content (control vs. lipid). The lipid-induced higher pressure (p < 0.05) was associated with an inhibition (p < 0.05) in the output of the vasodilatator PGI2, and an increase (p < 0.01) in the production of the vasoconstrictor PGF2 alpha. Indomethacin abolished differences in pressure, but produced a rise (p < 0.01) in vascular tone of both the control and lipid-containing solutions by inhibiting PGI2 synthesis. Prostacyclin was the only eicosanoid significantly correlated (p < 0.01) to vascular tone. The lipid emulsion was therefore linked to the inhibition of the conversion of PGH2 to PGI2. The ensuing greater PGH2 availability would result in vivo, in the increased synthesis of vasoconstricting eicosanoids. The lipid-containing solution produced vasoactive responses similar to those reported with tert-butyl hydroperoxide, suggesting that hydroperoxides monly used lipid emulsions could be causing a prostanoid-dependent vasoconstriction. |
8070685 | Postischemic inhibition of cerebral cortex pyruvate dehydrogenase. | Postischemic, mitochondrial respiratory impairment can contribute to prolonged intracellular lactic acidosis, secondary tissue deenergization, and neuronal cell death. Specifically, reperfusion-dependent inhibition of pyruvate dehydrogenase (PDH) may determine the degree to which glucose is metabolized aerobically vs. anaerobically. In this study, the maximal activities of pyruvate and lactate dehydrogenase (LDH) from homogenates of canine frontal cortex were measured following 10 min of cardiac arrest and systemic reperfusion from 30 min to 24 h. Although no change in PDH activity occurred following ischemia alone, a 72% reduction in activity was observed following only 30 min of reperfusion and a 65% inhibition persisted following 24 h of reperfusion. In contrast, no significant alteration in LDH activity was observed in any experimental group relative to nonarrested control animals. A trend toward reversal of PDH inhibition was observed in tissue from animals treated following ischemia with acetyl-L-carnitine, a drug previously reported to inhibit brain protein oxidation, and lower postischemic cortical lactate levels and improve neurological e. In vitro experiments indicate that PDH is more sensitive than LDH to enzyme inactivation by oxygen dependent free radical-mediated protein oxidation. This form of inhibition is potentiated by either elevated Ca2+ concentrations or substrate/cofactor depletion. These results suggest that site-specific protein oxidation may be involved in reperfusion-dependent inhibition of brain PDH activity. |
8070688 | On the use of the quenching of luminol luminescence to evaluate SOD activity. | Addition of horseradish peroxidase to a luminol solution (pH = 9.4) produces a burst of light followed by a steady luminescence that lasts for several minutes. This steady-state luminescence is readily quenched by SOD, with a Q1/2 concentration (the additive concentration needed to decrease by one-half the emitted luminescence intensity) of c.a. 4 ng/ml (14 mU/ml). The luminescence intensity decrease can then be employed to evaluate SOD activity in SOD-containing samples. However, the light intensity can also be quenched by additives, such as Trolox, that are able to trap luminol-derived intermediates. It is proposed that double quenching experiments must be performed in order to be able to relate the observed effect of an additive to its SOD-like activity. |
8070687 | Adenosine deaminase, 5'nucleotidase, xanthine oxidase, superoxide dismutase, and catalase activities in cancerous and noncancerous human bladder tissues. | Activities of adenosine deaminase (ADA), 5'nucleotidase (5NT), xanthine oxidase (XO), superoxide dismutase (SOD), and catalase (CAT) enzymes were measured in cancerous and cancer-free adjacent bladder tissues from 36 patients with bladder cancer and in control bladder tissues from 9 noncancer patients. Increased ADA and decreased XO, SOD, and CAT activities were found in cancerous bladder pared with those of cancer-free adjacent tissues and of control bladder tissues. Differences were also found between enzyme activities in the bladder of different disease stages and grades. In the cancerous tissues, only positive intracorrelations were found, but in the cancer-free adjacent tissues and control tissues, both positive and negative correlations were established between enzyme activities. Results suggested that purine metabolism and salvage pathway activity of purine nucleotides were accelerated in the cancerous human bladder tissues via increased ADA and decreased XO activities, probably together with changes in some other related enzyme activities and, free radical metabolising-enzyme activities were depressed in cancerous bladder tissues, which indicated exposure of cancerous tissues to more radicalic stress. |
8070686 | Influenza virus induces expression of antioxidant genes in human epithelial cells. | Influenza infections cause airway epithelial inflammation and oxidant-mediated damage. In this setting, cellular antioxidant enzymes may protect airway epithelial cells against damage resulting from toxic oxygen radicals produced by activated leukocytes. Therefore, we tested the effect of influenza virus infection, as well as exposed to human binant interferon-gamma (IFN-gamma), on gene expression for the antioxidant enzymes manganese superoxide dismutase (MnSOD), copper/zinc superoxide dismutase (Cu/ZnSOD), indoleamine 2,3-dioxygenase (IDO), and catalase in primary cultures of human airway epithelial cells. In these cells, both viral infection and IFN-gamma increased MnSOD and IDO mRNAs. In contrast, neither viral infection nor IFN-gamma affected Cu/ZnSOD gene expression, and both viral infection and IFN-gamma decreased catalase gene expression. The differential effects of viral infection on antioxidant gene expression and their further amplification by IFN-gamma are likely to be important protective mechanisms in viral airway infections. |
8070689 | Effects of reactive oxygen metabolites on norepinephrine-induced vasoconstriction. | Aortic rings, 4 mm in length, were obtained from rats and placed on isometric force transducers in oxygenated Krebs buffer. Following a period of stabilization, the cumulative dose response relationship to norepinephrine was assessed. The vessels were washed and allowed to return to baseline in Krebs buffer containing xanthine (0.5 mM). Xanthine oxidase (0.1 U/ml) was then added to the bath and vessels incubated for 30 min. The vessels were resuspended in Krebs buffer and cumulative dose-response curves to norepinephrine reevaluated. The results indicate that generation of reactive oxygen metabolites by xanthine/xanthine oxidase decreases the pD2 from 7.80 +/- 0.04 to 7.40 +/- 0.09 with the endothelium intact. Removal of the endothelium did not attenuate the contractile dysfunction, indicating that endothelial-derived metabolites were not mediating the loss of vasoconstrictor effectiveness. Maximal tension development did not differ between normal and oxidized vessel rings. Introduction of oxypurinol (0.2 mg/ml) to the bath prevented the loss of constrictor responsiveness, thereby confirming that all of the oxidants were derived from the xanthine/xanthine oxidase reaction. Superoxide dismutase (200 U/ml) partially prevented the loss of norepinephrine responsiveness produced by xanthine oxidase-derived radicals. The pD2 in the SOD + xanthine/xanthine oxidase-treated vessels rings (7.19 +/- 0.11) was significantly lower than control vessel rings (7.49 +/- 0.04) and significantly higher than xanthine/xanthine oxidase-treated vessels (6.89 +/- 0.06). Catalase (1000 U/ml) also partially attenuated the loss of vascular norepinephrine responsiveness.(ABSTRACT TRUNCATED AT 250 WORDS) |
8070690 | The correlation between active oxygens scavenging and antioxidative effects of flavonoids. | The abilities of 15 flavonoids as a scavenger of active oxygens (hydroxyl radical and superoxide anion) were studied. Hydroxyl radical (.OH) was generated by the Fenton system, and assayed by the determination of methanesulfonic acid (MSA) formed from the reaction of dimethyl sulfoxide (DMSO) with .OH. (+)-Catechin, (-)-epicatechin, 7,8-dihydroxy flavone, and rutin showed the .OH scavenging effect 100-300 times superior to that of mannitol, a typical .OH scavenger. The other flavonoids showed no .OH scavenging effect at their concentrations up to 50 microM. Baicalein, quercetin, morin, and myricetin unexpectedly increased the .OH production in the Fenton system. The flavonoids tested now, except monohydroxy flavones, were more or less inhibitive to the superoxide anion (O2) generation in the hypoxanthine-xanthine oxidase system. A great part of this inhibitory effect was likely owing to suppression of xanthine oxidase activity by the flavonoids. The flavonoids, which scavenged .OH or O2-, were necessarily antioxidants to the peroxidation of methyl linoleate. However, there was a type of flavonoid such as morin, which have neither .OH nor O2- scavenging effect, but was a strong antioxidant. |
8070691 | Enhanced urinary spontaneous luminescence in Duchenne muscular dystrophy. | Urinary spontaneous visible luminescence is enhanced in children with Duchenne Muscular Dystrophy (DMD). This result is indicative of systemic oxidative stress in DMD patients. It is proposed that measurement of the urinary luminescence could be employed to follow the progress of the disease, as well as the response of the patients to antioxidant therapy. |
8070692 | Effects of oxygen free radical scavengers on uranium-induced acute renal failure in rats. | Study was made to determine whether oxygen free radicals mediate uranium-induced acute renal failure (ARF). Superoxide dismutase (SOD), a superoxide anion scavenger, did not prevent uranium acetate (UA) (5 mg/kg, i.v.)-induced renal injury 48 h after injection. In contrast, dimethylthiourea (DMTU), a hydroxyl radical scavenger, significantly attenuated UA-induced rise in serum creatinine concentration (1.11 +/- 0.05 (DMTU) vs. 1.40 +/- 0.06 mg/dl (control), p < .05), and tubular necrosis. Dimethyl sulfoxide (DMSO), a hydroxyl radical scavenger, decreased UA-induced tubular damage. UA injection caused no increase in renal cortical malondialdehyde (MDA) content. DMTU and DMSO did not modify intrarenal MDA content. UA administration brought about significant increase in plasma renin activity but not in renal cortical renin content. Treatment with DMTU and DMSO had no effect on plasma renin activity or intrarenal renin content. It follows from these findings that DMTU and DMSO may attenuate UA-induced renal injury. Such a protective effect would not be mediated through modulation of lipid peroxidation or renin activity. |
8070693 | Ischemia-induced brain iron delocalization: effect of iron chelators. | Tissue damage in cerebral ischemia may be produced by acidosis-induced delocalization of intracellular iron which acts as a catalyst in oxidative reactions. Acidosis was induced either by homogenization and incubation of rat cortical homogenates in acidified buffers or by submitting hyperglycemic rats plete ischemia, a procedure that leads to intracellular lactic acidosis. The level of low molecular weight species (LMWS) iron was measured after filtration of tissue homogenates through a 10,000 Mr ultrafiltration membrane. When cortical tissue was homogenized in buffer pH 7, the level of LMWS iron was equal to 0.21 microgram/g. It was significantly enhanced by acidification of the homogenization medium, reaching 0.34 microgram/g at pH 6 and 0.75 microgram/g at pH 5. When the tissue was homogenized in water, the LMWS iron level reached 0.17 microgram/g in normoglycemic rats and 0.38 microgram/g (p < .05) in hyperglycemic rats. Both aerobic incubation of homogenates for 1 h at 37 degrees C and inclusion of EDTA in the homogenization medium led to further increases in the iron level. In order to demonstrate the deleterious role of iron in brain ischemia, the effect of treatment with bipyridyl, an iron-chelating agent, was assessed by measuring regional brain edema by the specific gravity method, 24 h following induction of thrombotic brain infarction. The treatment significantly attenuated the development of brain edema, reducing the water content of the infarcted area by about 2.5%. Taken together, these results support the hypothesis that a ponent of brain ischemic injury involves an iron-dependent mechanism. |
8070694 | Coinduction of nitric oxide synthesis and intracellular nonheme iron-nitrosyl complexes in murine cytokine-treated fibroblasts. | Murine fibroblasts treated with interferon-gamma plus tumor necrosis factor-alpha plus lipopolysaccharide produce nitrite and EPR-observable intracellular nonheme iron-thiol-dinitrosyl species. Inhibition of .NO synthesis or de novo tetrahydrobiopterin (BH4) synthesis decreases nitrite and the EPR signal. The effects of BH4 synthesis inhibition are prevented by sepapterin, which increases BH4 through the salvage pathway. |
8070695 | New reactive oxidizing species causes formation of carbon-centered radical adducts in organic extracts of blood following liver transplantation. | alpha-(4-pyridyl-1-oxide)-N-t-butylnitrone (4-POBN) radical adducts from Folch (chloroform:methanol) extraction of blood of transplanted livers exhibited a large 6-line electron paramagnetic resonance (EPR) spectrum. Slow EPR sample preparation involving freezing and thawing prior to extraction over 15 min yielded a spectrum assigned as a lipid-derived free radical species, whereas rapid (< 1 min) extraction without a freeze-thaw cycle yielded a mixture of radicals, one with coupling constants similar to the alpha-hydroxymethyl-4-POBN adduct (4-POBN/.CH2OH). Extraction with purified chloroform, however, yielded a much weaker, probably lipid-derived signal. Use of 13C-methanol in the Folch extracting solution yielded a 12-line EPR spectrum, indicating that a new, highly reactive oxidant species from blood following liver transplantation can convert organic solvents used in tissue extractions to free radicals. This hypothesis was supported by simulation of EPR spectra of free radicals extracted rapidly with Folch, which indicated that the spectrum contained two carbon-centered species, one with hyperfine coupling constants similar to the alpha-methylhydroxyl-4-POBN adduct, the other probably lipid-derived. Because the former originates from methanol in the Folch, extraction of samples with alcohol-free organic solvent is most likely superior when the potential for formation of stable oxidant species exists, such as after liver transplantation. |
8070696 | Mutual dependence of growth modifying effects of 4-hydroxynonenal and fetal calf serum in vitro. | Recently, the hypothesis has been put forward that 4-hydroxynonenal (HNE), an aldehydic product of lipid peroxidation, contributes to the mechanisms of oxygen toxicity and to the selective pressure exerted by exposure to hyperoxia. Here it has been studied whether HNE itself is involved in mechanisms that convey increased resistance of the cells to the toxicity of HNE. The following four cell lines, different in their basic biological features, were used: nonmalignant Chinese hamster lung fibroblasts V79 (established cell line), human carcinoma HeLa (established cell line), pigmented murine melanoma B16f10 (primary culture), and amelanotic murine melanoma B16BL6 (primary culture). The cells were pretreated in vitro with a toxic dose of HNE (50 microM), and afterwards the effect of a second exposure to the same dose of HNE on 3H-thymidine incorporation was examined. Cells were cultured in the absence and in the presence of fetal calf serum (FCS), because it had been shown that a growth modifying effect of HNE depends on an unknown serum factor. The results showed that, regardless of the type of cells, preculturing them with 50 microM HNE in the presence of serum changed the reactivity of the cells to added serum as well as to additional HNE treatment. Thus, HNE precultured cells incorporated less 3H-thymidine in the presence of serum than if cultured under serum-free conditions. On the other hand, HNE precultured cells became less sensitive to further HNE treatment, but only if cultured in the presence of serum.(ABSTRACT TRUNCATED AT 250 WORDS) |
8070697 | [Comparison of routine semen analysis with results of the hypo-osmotic test and hamster penetration test]. | In the program of semen preparation to intra uterine insemination (IUI) parison of the routine semen analysis with the results of the Hypoosmotic Test (HOS-T) and the Hamster Oocyte Penetration Test (HOP-T) was performed. The positive correlation between the sperm quality and the results of the used tests (HOP and HOS) was revealed. It was found that the essential indicator of the decreased fertilizing capacity of the semen is it's motility. The significance of the studied tests in the diagnosis and treatment of infertility was discussed. |
8070698 | [Ultrasound images of prostate and seminal vesicles in infertile male patients]. | The results of clinical examinations, semen analysis and endosonographic examinations of prostate and seminal vesicles were analysed in 172 male patients treated due to infertility. Ultrasound equipment with transrectal multiplane transducers 6.5 and 7.0 MHz frequency has been used to the evaluation of size, symmetry and echostructure of prostate and the seminal vesicles. In 62% patients pathological changes have been displayed in the prostate and 32% in the seminal vesicles. |
8070699 | [Usefulness of diagnostic ultrasonography for evaluation of scrotal organs]. | Scrotal sonography was performed on 172 patients treated for infertility ranging 1-10 years. The results of the sonographic examinations pared with palpations. Pathological deviations were found in 71.5% of patients using sonography and ony 53.5% of patients examined clinically. Our study found varicocele in 55.2% of patients, spermatoceles in 6.4% of patients and pathological amount of fluid surrounding the testicles in 15.1% of patients. The results of our study show that sonography should be used for more exact and more correct findings in the examination of scrotal organs and accurate monitoring of applied treatment. |
8070700 | [Self concept of men from childless married couples after receiving information about sperm value]. | The questionnaire included 220 men from childless married couples who referred to the Department of Reproduction and Andrology of the Medical Academy in Lublin for 4 months in 1992. The treatment period of childlessness in those couples ranged from several months to 17 years. The authors tried to establish if, and to what extent the receipt of information affected the well being and sexual life of those men. It was found out that the information and awareness of the value of own sperm resulted in the change of well being in 80.5% of the studied men. In the subjective evaluation they appeared to be more irritable in everyday life and/or their feeling about own value as men was reduced. Such changes were noticed both by those who had been informed about the proper test results as well as by those with test results varying from the standard. In almost half of the respondents (41.8%) the sexual activity was changed or the frequency of sexual satisfaction feeling was reduced. The obtained results as well as the lack of wider approach to this problem in Polish literature indicate the significance of further studies. |
8070701 | [Seasonal changes in results of semen analysis from male members of an infertile married couple]. | Analysis of 200 semen samples of men from childless couples was performed in order to evaluate the sperm characteristics during the year. Estimated were following features: semen volume, sperm density, motility and percentage of pathological forms. The sperm estimation data obtained from 4 seasons of the year was statistically evaluated. Statistically significant changes were found only in the percentage of pathological sperm forms. During the spring period the observed values were significantly higher than during summer and winter. From the correlation tables it appears that together with the increase of sperm density the percentage of pathological forms decreases. Whereas increase in density is correlated with the increase of sperm motility. It was also revealed that together with the increase of the percentage of pathological forms the motility decreases. Analogical results were obtained in all seasons of the year which indicates that there is a clear regularity existing. The least apparent dependencies were found in winter period. |
8070702 | [Congenital malformations of the epididymis and vas deferens as reasons for male infertility]. | Between 1966-1991 330 patients where the semen analysis revealed azoospermia and the histopathological examination of biopsy specimen of testis shown retained spermatogenesis and spermiogenesis underwent the surgical intervention. In 80% of cases congenital malformations of epididymis and vas deferens were found. The types of malformations detected during the surgery are discussed. |
8070703 | [Ultrasonographic investigations in diagnosis of congenital malformations of epididymis in cases of azoospermia]. | Between 1984-1991 in 28 patients referred for the surgical treatment for the reason of obstruction of epididymis outlet ducts there was a suspicion of a congenital epididymis malformation put after the physical examination. The ultrasound examination of the scrotum which was performed in all cases revealed the proper view of the epididymis in 5 cases, the proper head of the epididymis with the broad tubules and the lack of the corpus and cauda in 19 cases and in 4 cases the residual head of the epididymis located in region of the upper pole of the testis. Intraoperative findings were consistent with the ultrasound results in 75.0% of cases. The highest consistency between the ultrasonographic and intraoperative findings was found in the cases with the proper view of the head of the epididymis with agenesis of corpus and cauda. In 32.1% of cases malformations of epididymis and vas deferens were associated with the malformations of the urinary tract. |
8070704 | [Fertility disturbances in males working as professional computer operators]. | From 2376 patients who were diagnosed as infertile between 1986-1991, 20 puter operator males in the age of 26-40 were chosen (0.8%). Their working time was at least 5 hours daily and they have been working for 2-12 years (mean 7.7 +/- 3.3 years). The mean number of spermatozoa in 1 ml of sperm was 45.5 +/- 23.7 X 10(6)/ml, the percentage of properly motile spermatozoa equaled 21.5 +/- 12.2% and the percentage of pathological forms equaled 26.6 +/- 6.1%. The percentage of properly motile spermatozoa was decreased in all patients. There was not significant tendency of decreasing of the number of spermatozoa in 1 ml of sperm and percentage of properly motile spermatozoa dependent on the years of working in front puter monitors. Whereas percentage of pathological forms increases statistically significantly in dependency of the years of working. |
8070705 | [Androgens and the brain]. | Recent years investigations provided, that androgens belong to the group of neurosteroids synthetized and metabolized in the brain tissue by both: the cells (neurons and glia) and the white matter. Two basal metabolic pathways of androgens: aromatisation and 5-alpha-reduction probably serve different physiological functions in different life periods. During the fetal life are the crucial processes for the organisation of the brain centers toward male patterns. At latter stages might play an important role in the feedback mechanisms controlling LH secretion. The action of neurosteroids is mediated by classic nuclear receptors, but also by cell-membrane receptors, and this effect is rapid and specific. Androgens can also modulate the action of others neurotransmitters by binding to their cell-membrane receptors, eg. GABA-A. |
8070706 | [Intrauterine insemination as a method of treating male infertility]. | One of the method of treatment of the infertile couple due to the male factor is the Intra Uterine Insemination (IUI). The references on the subject are divergent. This is caused by the lack of the parable classification in patients selection for the treatment, procedure of semen preparation and the results estimation. The different efficiency of this treatment method and it's direct and indirect costs are emphasized. In our studies IUI was applied in 42 women from the couples infertile due to the male factor. There were 3 pregnancies obtained (7.0%) which gives the result of 4.3% of pregnancies respectively per treated cycle. Each stage of the procedure was analysed, beginning from the criteria of patients selection, the way of the semen preparation as well as the time of treatment in respect to the obtained results--the percentage of the patients who became pregnant. |
8070707 | [Observation of some semen parameters in men with varicocele]. | Among 172 examined male patients varicoceles have been found in 57.6% patients. The frequency of varicocele appearance increased according to the fall of sperm concentration. Simple relations between sperm motility and varicocele have not been observed. Larger per cent of pathological sperm forms in patients with varicoceles has been shown. In patients with varicoceles three times as frequent appearance of richer periprostatic and periseminnal blood vessels have been observed parison with patients without varicocele. |
8070708 | [Remarks on artificial intrauterine insemination of women with abnormal semen]. | Despite of the great deal of publications on artificial insemination the real effectiveness of the procedure is not clearly estimated so far. This is why in the presented paper authors tried to evaluate the effectiveness of the artificial intrauterine insemination with the abnormal sperm which was laboratory classified as oligo-astheno-teratozoospermia. The sperm which was prepared to the insemination according to the technic enabling to select only the population of the motile spermatozoa. The women were inseminated after the proper hormonal preparation and ultrasound monitoring of ovulation. 153 intrauterine inseminations were performed in 17 women. There was no case where the insemination was performed longer than during 6 consecutive cycles. There was no pregnancy obtained. The e to the conclusion that the intrauterine insemination with the abnormal semen of oligo-astheno-teratozoospermia type prepared in accordance with the used in the study technic is not an effective way of treating the infertile couple. |
8070709 | [Comparison between the influence of estradiol benzoate, testosterone propionate and human chorionic gonadotropin on initiation of spermatogenesis in the rat]. | Newborn male rats were injected daily from the 5th to 15th day of life with: EB in doses of 6.2 or 12.5 or 25.0 micrograms and TP in doses of 1.2 or 2.5 or 5.0 mg (experiment 1), and with hCG (experiment 2) in doses of 2.0 or 4.0 or 8.0 I.U. Animals were sacrificed on the 16th day of life, testes and seminal vesicles were taken and fixed. The function of seminiferous tubules was examined by quantitative analysis of spermatogenesis. EB increased the mean number of germinal cells. TP stimulated differentiation of spermatogonia, but it decreased the number of all germinal cell types. Only the lowest dose of hCG stimulated the mean number of germ cells in the earliest stages of spermatogenesis, hCG used in the higher doses suppresses maturation of seminal tubules and decreases testicular weight. |
8070711 | [Influence of intratesticular injections of tamoxifen on spermatogenesis and testosterone secretion in the rat]. | Three groups of adult Wistar rats were injected every second day with: 5 or 10 or 20 micrograms of tamoxifen (Tx) to the right testis. Left testis was injected with the same volume of solvent. Control group received the solvent for Tx. Animals were killed after 15 days. Blood samples were taken from heart for testosterone determinations. Both testes were taken for histological examination and quantitative analysis of seminiferous epithelium was performed. Testosterone was analysed with radioimmunoassay method. It was demonstrated that intratesticular supply of Tx caused significant rise in the number of type A spermatogonia and significant increase of testosterone concentration in the blood. It is concluded that Tx influences spermatogenesis in adult rats through stimulation of the earliest steps of gamete formation. Testosterone may or may not mediate this effect. |
8070710 | [Tamoxifen and spermatogenesis in rats subjected to effects of estradiol]. | During 14 subsequent days male Wistar rats received subcutaneously 50 micrograms of EB and different doses of tamoxifen intratesticularly. Action of EB was examined parison with the group, which received the solvent for EB only. EB caused the reduction in the mean testis weight, degenerative changes of germinal cells and decrease of blood testosterone level to undetectable values. Tamoxifen did not prevent these changes, but revealed a positive influence on the mean numbers of spermatogonia, spermatocytes and spermatids, including spermatozoa. It indicates that tamoxifen may stimulate the whole spermatogenesis in spite of the inhibition of testosterone production. |
8070712 | [Level of zinc and magnesium in semen taken from male partners of married infertile couples]. | There was a preliminary study performed on the differences of zinc and magnesium levels in semen serum from 46 males from the infertile couples. Zinc and magnesium concentration was measured by the use of atomic absorption spectrophotometer. There was no statistically significant differences noticed between the mean concentration of zinc and magnesium in normal and pathological semen serum. Zinc and magnesium levels did not show correlation with the volume of the sperm and with the percentage of pathological forms. Whereas in the cases with the pathological spermiograms there was positive correlation revealed between the concentration of zinc and magnesium and the quantity of spermatozoa in 1 ml along with the negative correlation with the percentage of motile spermatozoa. |
8070713 | [Usefulness of examining gonadotropin hormones and testosterone in men with abnormal semen]. | The aim of the study was to estimate the usefulness of some hormonal investigations in cases of males with abnormalities in semen analysis in the diagnosis of the male factor in the infertile couple. 107 males with the abnormalities in spermiogram underwent the analysis of the blood serum hormonal levels. Estimated was the level of FSH, LH, prolactin and testosterone. The control group consisted of 31 males with normospermia. The study group was divided according to terminology. In all four groups of infertility the mean values of FSH were significantly higher than in control group. There was no significant differences in LH levels between the groups. The mean values of prolactin level were not significantly higher in the cases of hypospermia than in normospermia group, but significantly higher in the other groups of infertility. The mean level of testosterone was significantly lower in all four groups of infertility parison with it's mean level in normospermia group. It was found that the FSH is the most discriminatory hormone in respect of infertility classification and therefore it's diagnostic value is the highest among the four hormones investigated. |
8070714 | [Detection and treatment of hyperprolactinemia in male infertility]. | The role of prolactin in males has not been satisfactorily explained. It has been proved that hyperprolactinemia has a negative effect both on spermiogenesis and spermatogenesis. It is widely known that the secretion of the pituitary hormones is of a pulsating character and occurs in the diurnal rhythm. Therefore, in order to select a group of patients with hyperprolactinemia qualified for Bromocriptine treatment it was necessary to test them for prolactin. 3 morning tests were taken at 15 minute intervals. The selected male group was later treated with Bromocriptine, following the method of administration mended by the producer. Next the level of prolactin in patients serum was again determined. It has been determined that a single prolactin test is sufficient to diagnose hyperprolactinemia. In most males 3 prolactin tests were always either pathologic or normal. Most of the selected hyperprolactinemia--affected males after Bromocriptine treatment displayed positive therapeutic effects. The level of prolactin has dropped considerably and the potency has increased. The improvement in the semen picture varied from patient to patient. |
8070715 | [Evaluating the effect of smoking tobacco on some semen parameters in men of reproductive age]. | Seminal fluid indexes (sperm count, motility, pH, morphology) were examined in 40 smokers and 30 nonsmokers. The sperm count and motility were lower in smokers. Smokers have also higher incidence of pared to nonsmokers. There was no difference between pH and sperm morphology in smokers and nonsmokers. Additionally, smokers have higher levels of endogenous 17 beta-estradiol and sperm count below normal in nonsmokers. These results suggest that inveterate smoking can diminish fertility in men. |
8070716 | [Examining the effects of tobacco smoking on levels of certain hormones in serum of young men]. | Dehydroepiandrosterone (DHEA), testosterone (T), 17 beta-estradiol (E), prolactin (PRL) and gonadotropins (FSH, LH) were examined in 30 smokers and 25 nonsmokers. The mean E level was higher in smokers than nonsmokers, whereas the levels of T and DHEA are similar and did not differ significantly in pared to nonsmokers. Smokers have also lower mean levels of LH, FSH and PRL than nonsmokers. However, smokers with low prolactin levels have also low sperm percent motility, these results suggest that changes in endocrine profile due to cigarette smoking can reduce the fertility. |
8070717 | [Histologic evaluation of testis in men with azoospermia in light of hormonal determination]. | The causes of azoospermia may be of varied nature and are often difficult to determine. Generally, there are two morphological-clinical types of azoospermia. The first is due to the occlusion of the outgoing seminal tracts. The second is manifested by the lack of seminiferous epithelium, diagnosed on microscopic examination as acquired or primary Sertoli Cell Syndrome. In order to establish the distinctive features of both types of azoospermia a group of azoospermia--affected males underwent a morphological-biochemical analysis. 38 patients with azoospermia had surgical biopsy of testes, and hormonal determination of the pituitary gland and testis i.e. prolactin, LH, FSH, testosterone. Microscopic examination helped to select a group with Sertoli Cell Syndrome. This group exhibited statistically significant thickening of the basement membrane and FSH--levels markedly elevated in relation to both the norm and other azoospermia--affected patients. The above findings are in conformity with the recent research on the increase of FSH--level in azoospermia, and particular in Sertoli Cell Syndrome. They also confirm the validity of carrying out biopsies in the aforementioned clinical group because of the possibility of selecting patients for anastomosis of spermatic ducts or spermocele implantation. The fact that Sertoli Cell Syndrome is panied by a high FSH level could be utilized for the screening of patients for testes biopsy. |
8070718 | [Eosin and water tests and results of conventional semen analysis]. | Semen analysis was performed in 95 men and the results of routine examination were correlated with two sperm viability tests: eosin (TE) and water test (TW). Results of TE and TW were expressed as a percent of spermatozoa revealing a functional integrity of the cell membrane. Linear regression analysis was used. Patients were divided into 3 groups: normozoospermia (n = 46), oligozoospermia (n = 27) and profound oligozoospermia (2-4 x 10(6) sperm/ml). No correlations were demonstrated between viability tests and the sperm number. TE and TW significantly positively correlated with each other in all groups. At normo- and oligozoospermia TE and TW positively correlated with the percent of motile spermatozoa. TW did not show such a correlation in men with profound oligozoospermia. It seems that TE and TW can be used alternatively. TW may be of great importance in men with very low sperm count. |
8070719 | [Reduced-size liver transplants in children]. | Orthotopic liver transplantation is now used for children with end-stage liver disease, but the scarcity of size-matched liver allografts for children has limited its use. Reduced-size liver transplantation, in which only part of the liver is used as a graft, es size disparity and increases significantly the potential donor pool for children. A 4-year-old boy with fulminating hepatic failure due to hepatitis became the first case of reduced-size liver transplantation in Israel. A left hepatic lobe allograft from an adult donor was used. The boy is home and well 9 months after transplantation. Reduced-size liver transplantation was first performed in a child by Bismuth and Houssin in 1984. Reports from several centers show that survival of recipients of reduced-size liver allografts and the rate of retransplantation does not differ significantly from that in recipients of full-sized livers. |
8070720 | [Laparoscopic cholecystectomy using the Hasson trocar]. | Laparoscopic cholecystectomy has e the standard operation for symptomatic gallstone disease. There is general agreement that the advantages of this procedure in selected patients outweigh those of conventional open cholecystectomy. However, technical aspects of the procedure may expose the patient to severe and even plications, such as bowel or bladder perforation or injury to major blood vessels. In our opinion plications are avoided by the routine use of the blunt-tipped Hasson trocar, introduced through a 2 cm infra-umbilical incision in an open laparoscopic technique. We have used it successfully in 120 consecutive patients and believe it to be the procedure of choice for laparoscopic cholecystectomy. |
8070721 | [Invasive papillary thyroid carcinoma]. | Papillary carcinoma, the mon malignant tumor of the thyroid, infrequently invades the upper aerodigestive tract (larynx, pharynx, trachea and esophagus). However, when invasion does occur, it is a source of significant morbidity and excess mortality; the method of treatment is controversial. In our opinion surgery is the primary treatment modality. Local invasion of the aerodigestive tract by this tumor can be successfully treated by total or subtotal thyroidectomy, excising malignant tissue while preserving function of aerodigestive tract structures. Adjuvant therapy using radioiodine or external beam radiotherapy should be considered integral to any treatment plan. We present our experience with 4 patients with invasive thyroid papillary carcinoma to the larynx, trachea and esophagus. |
8070723 | [Atrial septal aneurysm and paroxysmal atrial fibrillation]. | A 48-year-old man was admitted because of treatment-resistant, paroxysmal atrial fibrillation. Transthoracic, 2-dimensional echocardiography revealed a "mass" within the left atrium, thought to be a tumor. Transesophageal echocardiography showed it to be an atrial septal aneurysm. There is a relationship between atrial septal aneurysm and atrial supraventricular tachyarrhythmias and systemic emboli. |
8070722 | [Interferon for hemangiomas of infancy]. | Hemangioma, the mon tumor of infancy, is usually harmless. It frequently appears soon after birth, proliferates for 8-18 months, and then slowly regresses over the next 5-8 years, leaving the skin normal or only slightly blemished. However, hemangiomas sometimes cause devastating tissue damage and may be associated with thrombocytopenia and life-threatening hazards. About a third of these cases respond to corticosteroid therapy, but often with rapid rebound following its discontinuation. Successful treatment of large and life-threatening hemangiomas with interferon alpha-2a has recently been reported. We found it effective in a 3.5-month-old male with a large symptomatic hemangioma. After 6 months of daily interferon alpha-2a (Referon, Hoffman-LaRoche), 3 million units/m2/day, all symptoms disappeared and the lesion was halved in size. There were no significant side-effects. This treatment is effective and safe and should be considered in infants with large, symptomatic hemangiomas. |
8070729 | [Attitudes of courts, physicians and psychiatric committees to court-ordered psychiatric hospitalization]. | Legal responsibility for the mentally ill has long been a dilemma. Public opinion with regard to the current law, which holds that the mentally ill are not responsible for their actions, is divided. We assessed 30 cases of psychiatric mitted by court order following a criminal act. No relation was found between the nature of the transgression and the nature or seriousness of the psychiatric disorder. Interestingly, those mitted the more serious crimes, such as murder, usually mitted fewer criminal acts in the past. The functioning of the mittees in charge of releasing mitted by court order has improved substantially under the new law for the treatment of the mentally ill. They now assess patients with considerably greater frequency. The reports to the courts of examining physicians tend to be general, with little attempt to differentiate ability to stand trial and responsibility for actions. On the other hand, treating physicians relate mainly to the patient's illness, rather than to the crime for which he mitted. |
8070730 | [The Amsterdam air disaster--management and fate of casualties]. | On Sunday, Oct. 4, 1992, an E1 A1 Boeing cargo plane crashed into a 10-story block of flats in the Bijmermeer, on the outskirts of Amsterdam. About 8 people died at the site of the disaster. 37 patients were treated in local hospitals within 90 minutes of the disaster, 16 of whom were admitted. 3 suffered severe, and 6 moderate burns (> 15% and 10-15% of body surface area, respectively). Although there were relatively few injured, a full-scale disaster response was evoked, providing an opportunity to study the effectiveness of current disaster plans. The rapid response of the ambulance service and the hospitals involved indicates that rehearsing disaster preparations is effective. The dispersal of the injured to several nearby hospitals prevented overloading of casualty departments. Secondary transfer of severely burned patients to the burn center was efficient and followed current guidelines. In retrospect, munication between the various services might be subject to minor criticism, no problems were encountered which interfered with proper execution of the rescue operation. No one who survived the immediate impact died. |
8070733 | Safety evaluation of lipase G from Penicillium camembertii. | Lipase G, a partial glycerides eliminating enzyme produced by Penicillium camembertii, was subjected to safety evaluation studies to establish its safety when used as a processing aid in the food industry. The toxicological studies on the enzyme included a 90-day gavage study with rats, a mutagenicity study using bacteria, and a pathogenicity study using mice. The no-adverse-effect level from the 90-day gavage toxicity study was 2000 mg/kg body weight/day for rats. There was no evidence of mutagenic potential. The micro-organism was evaluated for pathogenicity using mice and classified as a non-pathogen. Results indicate that the production and use of lipase G may be regarded as safe for the enzyme production worker and the consumer. |
8070734 | Aluminium uptake from some foods by guinea pigs and the characterization of aluminium in in vivo intestinal digesta by SEC-ICP-MS. | The uptake of ingested aluminium (Al) from food monly consumed in a normal human diet was investigated by feeding five test diets to guinea pigs. Al concentrations were measured in the femur, brain, kidney and upper intestinal contents. Consumption of these diets did not lead to elevated Al levels in brain. Levels of Al in the bone were elevated in animals fed sponge cake with a permitted Al-containing additive, and the presence of citrate as orange juice enhanced bone deposition and increased kidney Al levels. Less than 1% of Al in the upper intestinal contents was found in the soluble fraction, and characterization by SEC-ICP-MS indicated that this Al was not present as Al-citrate. |
8070735 | Effect of ammoniation of aflatoxin B1-contaminated cottonseed feedstock on the aflatoxin M1 content of cows' milk and hepatocarcinogenicity in the trout bioassay. | The effectiveness of ammonia in inactivating aflatoxins in contaminated cottonseed was investigated. Two aflatoxin-contaminated cottonseed lots were treated separately using an atmospheric pressure, ambient temperature ammoniation procedure (APAT) or a high pressure, high temperature ammoniation procedure (HPHT), and incorporated into dairy cow rations. Isocalorific diets containing 25% defatted, dried milk from cows fed aflatoxin-contaminated cottonseed without or with APAT or HPHT treatment, or an aflatoxin-free human mercial milk powder, were then fed for 12 months to rainbow trout (Oncorhynchus mykiss). Aflatoxin M1 (AFM1) concentrations in milk powders without and with seed treatment were: APAT, 85 and < 0.05 microgram/kg; HPHT, 32 and < 0.05 microgram/kg. In the APAT experiment, trout consuming the diet containing milk from cows fed the aflatoxin-contaminated cottonseed had a 42% incidence of hepatic tumours; APAT cottonseed treatment reduced this to 2.5%. Positive controls were included to demonstrate trout responsiveness. AFB1 fed continuously for 12 months at 4 micrograms/kg resulted in a 34% tumour incidence, whereas positive controls fed 20 micrograms AFB1/kg, 80 micrograms AFM1/kg, or 800 micrograms AFM1/kg for 2 wk and killed 9 months later had a 37, 5.7 and 50% incidence of tumours, respectively. These data demonstrate that APAT ammonia treatment of aflatoxin-contaminated dairy cattle cottonseed feedstock abolished the detectable transfer of AFM1 or AFB1 into milk powder, and greatly reduced the carcinogenic risk posed by any carry-over of aflatoxins or their derivatives into milk. In addition, the results confirm AFM1 to be a lower level hepatocarcinogen parison with AFB1 in the trout carcinogenicity assay. In the separate HPHT experiment, no tumours were observed in the livers of trout fed diets containing milk from either the ammonia-treated or untreated source, or the control diet containing 8 micrograms AFM1/kg. Positive controls fed 64 micrograms AFB1/kg for 2 wk exhibited a 29% tumour incidence 12 months later. Thus in this experiment, neither AFM1 at 8 micrograms/kg nor any HPHT-derived aflatoxin derivatives that might have been carried over into milk, represented a detectably carcinogenic hazard to trout. |
8070736 | Transfer of the food mutagen PhIP to foetuses and newborn mice following maternal exposure. | The food mutagen PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine) is a liver carcinogen in neonatal mice. In this study the transfer of PhIP to foetuses and neonates following a single ip dose (4.7-5.2 mg/kg body weight) to pregnant or lactating C57Bl/6 mice was studied by tissue extraction and HPLC analysis. A transplacental transfer of unchanged [3H]PhIP to foetuses was demonstrated; the highest foetal levels were observed at late gestation. Autoradiography of mice injected iv with [2-14C]PhIP (1.4 mg/kg) during late gestation showed a high and selective localization of radioactivity in the pigmented parts of the foetal eye and a moderate level of radioactivity in the foetal liver, gastro-intestinal contents, urine and in the uterine fluid. HPLC analysis of stomach contents and tissues of newborn mice exposed for 4 hr to lactating dams dosed ip with [3H]PhIP (5.2 mg/kg) showed the presence of unchanged PhIP suggesting excretion of PhIP in the milk of the dams. The results in this study raise concern that exposure to PhIP during pregnancy and nursing may result in a transfer of this food mutagen to foetuses and infants. |
8070737 | Dietary effects on the uptake of benzo[a]pyrene. | It has been established that exposure to polycyclic aromatic hydrocarbons (PAHs), or more specifically benzo[a]pyrene (B[a]P), either by inhalation through cigarette smoking or by contact through occupational exposure of the lungs or skin, can result in cancerous lesions. It appears that the general population consumes more B[a]P from food than from smoking. Despite this, epidemiological studies have not implicated B[a]P from foods as a causative factor in some human cancers. This lack of an epidemiological correlation between cancer incidence and intake of dietary PAHs/B[a]P could be due to some 'protective' or 'detoxification' mechanism. Despite the abundance of literature regarding the food content of B[a]P, there are few data concerning its uptake from foods. In the present study we investigated the intestinal absorption of B[a]P from foods using bile duct cannulated rats and radioactive B[a]P. [14C]B[a]P was first added to solvents such as water, corn oil, liquid paraffin or 50% ethanol, which were the administered by gavage to rats fed diets with or without added carbon. Additionally, food polyphenols such as quercetin and chlorogenic acid were also tested for their effect on the absorption of B[a]P. The results indicated that the excretion of B[a]P in the bile was reduced by water, carbon, quercetin and chlorogenic acid but was potentiated by corn oil. plement the in vivo studies, some in vitro tests to investigate the efficiency of B[a]P extraction from different foods using water or oil as solvents were also performed. These tests indicated that extraction of B[a]P from foods was affected by the solvent. It is postulated that reduced solubility, physical adsorption and the formation of chemical adducts between B[a]P and some food ingredients, play a sporadic, although still not well determined, role in reducing the absorption of B[a]P from the gut. The results of these studies suggest that B[a]P absorption from the intestinal tract is markedly affected by ponents, and that this may be a factor that contributes to the lack of an epidemiological correlation between some human cancers and the B[a]P content of foods. |
8070738 | Effects of beta-carotene and canthaxanthin on liver xenobiotic-metabolizing enzymes in the rat. | The activities of several phase I and phase II xenobiotic-metabolizing enzymes have been measured in liver microsomes and cytosol of male rats that had been fed for 15 days with diets containing beta-carotene or canthaxanthin (300 mg/kg diet) or an excess of vitamin A (70,000 IU/kg diet), or to which beta-carotene had been administered by ip injections (7 x 10 mg/kg body weight). Microsomal cytochrome P-450 and the associated NADH- and NADPH-cytochrome c reductases were assayed, as well as several phase I and phase II enzyme activities. Phase I activities were markers of the families 1, 2, 3 and 4 of P-450; phase II activities were microsomal UDP glucuronosyl transferases (UGT) and cytosolic glutathione S-transferase (GST). Canthaxanthin accumulated in liver to a much higher level than did ingested or injected beta-carotene. Canthaxanthin increased the liver content of cytochrome P-450 (control value x 1.7), and the activity of NADH-cytochrome c reductase (x 1.5), and of some P-450-dependent enzymes (ethoxy-, methoxy-, pentoxy- and benzoxyresorufin O-dealkylases; x98, x15, x6.5 and x13, respectively), but not of others (erythromycin N-demethylase, nitrosodimethylamine N-demethylase and laurate omega-hydroxylase). Phase II activities were also increased: UGT1 (x3.4), UGT2 (x1.2) and GST (x1.2). This induction profile, characterized by the very strong increase of the activity associated with P4501A1, and the co-induction of UGT1, closely resemble that of a classical inducer, 3-methylcholanthrene. By contrast, neither beta-carotene (fed or injected), nor an excess of vitamin A induced any significant variation of the enzyme activities measured. |
8070741 | The identification and classification of skin irritation hazard by a human patch test. | There exist various regulatory instruments the purpose of which is to ensure that the intrinsic toxic hazards associated with substances and preparations are identified. In the context of identification of skin irritation potential, the method is normally the Draize test. Guidance notes provided by the OECD and the EEC expect that corrosive substances will have been screened out by a variety of methods. Substances or preparations which cause a sufficient degree of skin irritation will be classified as skin irritants. The primary motivation behind the present work was to introduce the concept that it is possible to assess the hazard potential of a substance or preparation to produce skin irritation in a human study. In the example presented here, 20% sodium lauryl sulfate (SLS) has been chosen as the positive control. With the protocol currently devised, occluded patch treatment with 20% SLS for up to 4 hr produces an irritant response in just over half of the panel. An irritant response is taken as a clinically evident and significant increase in erythema, oedema or dryness--a minimum of a+ reaction on the ICDRG scale. At such a level of response with the positive control (both in terms of intensity and in proportion of the panel), it is then possible to judge and/or to determine statistically, whether the test material has produced a level of skin irritation which is similar to, greater, or lower than the positive control. In this way a human patch test protocol can form a ponent of a strategy for the replacement of animals in determination of skin irritation and corrosion potential. By use of a careful and progressive protocol and parison of test data against a positive control it is both possible and practical to classify substances and preparations in terms of their skin irritation potential using that endpoint in the species of concern, man. |
8070740 | Effects of sustained low-level muscarinic agonism in rats. | Sustained, low level muscarinic activity was induced in rats by feeding the muscarinic agonist and experimental drug candidate CI-969 at 50, 100 and 200 mg/kg body weight/day for 4 wk. Except for urine staining, clinical signs typical of acute high-dose exposure to muscarinic agonists were not observed. A dose-related suppression of body weight gain approached 60% at the high dose, but no significant effects on haematology or clinical chemical parameters were observed after 4 wk of exposure. Corneal opacities with histopathological features including neovascularization, acanthosis and stromal proliferation were observed in a dose-related fashion in both sexes at 100 and 200 mg/kg/day. Hypertrophy of the Harderian and lacrimal glands also occurred, probably as an adaptive response to sustained muscarinic activity. Lacrimal gland concentrations of the muscarinic agonist were in the range of pmol/mg tissue and therefore significant direct exposure of cornea to pound through the tears was discounted. The presence of corneal muscarinic receptors was investigated to determine whether opacities could be related to direct, receptor-mediated events in the cornea; however, no specific binding of the muscarinic receptor radioligand [3H]quinuclidylbenzilate was detected. Because muscarinic agonist-induced opacities can be inhibited by scopolamine, the apparent lack of muscarinic receptors in the cornea indicates that the opacities are not a direct effect, but are instead secondary to muscarinic events at another site. To our knowledge, this is the first report of corneal opacities induced by a muscarinic agonist. |
8070742 | Effect of Brassica nigra on benzo[a]pyrene mutagenicity. | Male rats were given diets containing Brassica nigra (mustard seed) powder at 0, 1, 5 or 10% for 1 month and then exposed to benzo[a]pyrene (B[a]P. 1 mg by ip injection). The antimutagenic effect due to mustard was assessed by testing the urine of rats fed diets with and without mustard. There was a significant (P < 0.001) reduction in reversion frequency of the TA98 and TA100 strains of Salmonella typhimurium in mustard-fed groups. This protective effect was seen with all three doses of mustard. The study demonstrated that mustard (Brassica nigra) can be a potent antagonist of the adverse biological effects of the ultimate metabolites of B[a]P, a ubiquitous environmental genotoxicant. |
8070739 | Comparison of the hepatic effects of coumarin, 3,4-dimethylcoumarin, dihydrocoumarin and 6-methylcoumarin in the rat. | The mechanism of coumarin-induced hepatotoxicity in the rat has been investigated paring the effects of coumarin with those of three coumarin derivatives, namely 3,4-dihydrocoumarin (DHC), 3,4-dimethylcoumarin (3,4-DMC) and 6-methylcoumarin (6-MC). Male Sprague-Dawley rats were fed either control diet or diets containing 0.5 or 0.75% coumarin, 0.76% DHC, 0.6 or 0.9% 3,4-DMC or 0.82% 6-MC for 13 wk. The dietary levels of 0.5% coumarin and 0.6% 3,4-DMC, were equimolar (3.43 mmol/100 g diet), as were the dietary levels of 0.75% coumarin, 0.76% DHC, 0.9% 3,4-DMC and 0.82% 6-MC (5.14 mmol/100 g diet). All treatments resulted in an increase in relative liver weight, but only coumarin increased plasma alanine aminotransferase and aspartate aminotransferase activities. Morphological examination of liver sections from coumarin treated rats revealed vacuolation of centrilobular hepatocytes and bile duct hyperplasia. Cholangiofibrosis was also observed, particularly in rats given 0.75% coumarin. Treatment with DHC produced no abnormalities, whereas a slight hypertrophy of centrilobular hepatocytes was observed in some 3,4-DMC treated animals and a slight vacuolation of individual hepatocytes was noted in some 6-MC treated rats. DHC, 6-MC and particularly 3,4-DMC treatment resulted in an induction of cytochrome P-450 dependent mixed function oxidase enzyme activities. All treatments induced hepatic GSHS-transferase and gamma-glutamyltransferase activities, induction being most marked in rats given coumarin and 6-MC. These results provide further evidence that coumarin-induced hepatotoxicity in the rat is due to the formation of a 3,4-epoxide intermediate. |
8070745 | [Drug dependence and withdrawal in chronic pain patients]. | Drug dependence in "pain patients" usually involves primary headache syndromes with chronicity resulting from the use of analgesic-psychotropic or bination preparations. Since, during the withdrawal phase, enhancement of pain intensity together with other abstinence phenomena are to be expected, hospitalization is usually indicated. Psychosomatic pain syndromes with dependence on benzodiazepine derivatives represent the second largest group. In these patients, withdrawal is effected stepwise, usually on an outpatient basis. Opioid analgesics administered to patients to treat chronic pain do not necessarily lead to the development of tolerance. Occasionally, dependency is observed in organic or psychosomatic pain states. In all three groups, typical addition behavior is rare. |
8070748 | [Optimal or maximum acid inhibition in ulcer therapy? A decision guide for routine general practice based on personal studies]. | The mucosal barrier in the stomach plete only when the mucous layer has e saturated with bicarbonate. The latter arises as a waste product, as it were, of acid production in the parietal cell, but is then actively secreted via the surface epithelial cells and tight junctions. If the acid secretion is inhibited by means of drugs, the bicarbonate concentration also decreases. This situation probably occurs only when the bicarbonate batteries in the mucous layer and the surface epithelial cells have e "discharged" after a period of about 24 hours, which indicates an intermittent, non-maximum block. In the region between the surface epithelial cells and the mucous layer, Helicobacter pylori has its ecological niche. As studies with, for example, ranitidine nocte, amoxycillin and metronidazole have shown, a 12 hour alternation between acid secretion inhibition and the physiological buildup of the gastric mucosal barrier appears to promote the eradication of Helicobacter pylori. Hypotheses about the role of sudden ammonia production on the part of the pathogen and on the regulation of bicarbonate and acid production in humans underscore these findings. |
8070750 | Dose-dependent testicular toxicity of propylene oxide in rats induced by repeated intraperitoneal injections. | The dose-dependent testicular toxicity of propylene oxide (PO) was evaluated in male Wistar rats when administered by intraperitoneal injections. In 23 mg/kg, 47 mg/kg, and 93 mg/kg groups, PO was given three days a week for six weeks, while PO was given three days a week for two weeks plus once a week after the third week in a 186 mg/kg group. In the 186 mg/kg group, the epididymal weight and sperm count in the body plus tail of the epididymis decreased, while the rate of sperm with morphological abnormalities increased significantly. The number of sperm with an immature head increased slightly, although significantly, even in the 47 mg/kg group and a dose-dependent effect could be seen. The serum testosterone concentration did not change significantly and there were no apparent histopathological changes in Leydig cells in any of the treatment groups. This is the first detailed study concerning the dose-dependent testicular toxicity of PO. |
8070751 | Effectiveness of relative low-dose interferon treatment for patients with chronic hepatitis C. | To demonstrate effectiveness by relative low-dose of interferon treatment for patients with chronic hepatitis C, we investigated the histological activity index (HAI) score of liver tissue, hepatitis C virus (HCV) genotype by polymerase chain reaction (PCR) with type-specific primers, HCV RNA levels petitive PCR, serum aminotransferase, sex, age, history of blood transfusion and history of hepatitis in patients with chronic hepatitis C prior to treatment. Twenty-two patients were treated with human lymphoblastoid interferon (3 MU daily, 2 weeks, 3 MU thrice a week, 6 weeks, 1.5 MU thrice a week, 16 weeks) for 24 weeks, of whom 10 (45.5%) were responders within a 6 month follow-up. HAI score before treatment was significantly lower in responders than in bined group of relapse patients and nonresponders (7.5 +/- 3.4 vs. 12.0 +/- 3.1, p < 0.01). The prevalence of responders in patients with genotypes III and IV was significantly higher than in those with genotype II (85.7% vs. 21.4%, p < 0.05). HCV RNA level (logarithmic transformed copy per 50 microliter of serum) was significantly lower in responders than in bined group of relapse patients and nonresponders (4.8 +/- 1.2 vs. 5.7 +/- 0.8, p < 0.05). In case of other pretreatment factors, there were no significant differences between responders and bined group relapse patients and nonresponders. Thus severe histological changes in the liver, HCV genotype II and high HCV RNA levels are markers of unfavorable effects of interferon treatment for patients with chronic hepatitis C. |
8070752 | The substitution of troponin in bullfrog and chicken myofibrils by rabbit skeletal troponin, troponin-T and troponin-T1. | The substitution of troponin in bullfrog skeletal myofibrils by rabbit skeletal troponin, troponin T and troponin T1 was examined by the densitometry of the SDS gel-electrophoretic patterns. The troponin in the myofibrils was replaced by the added rabbit skeletal troponin and troponin T (tropomyosin ponent of troponin) to almost the same extent. On the other hand, troponin T1, the N-terminal side fragment of two chymotryptic fragments of troponin T replaced troponin in the myofibrils less effectively than either troponin or troponin T. Troponin T, also replaced troponin in the myofibrils from rabbit and chicken striated muscles, less effectively than troponin T. This suggested that, in addition to the N-terminal side troponin T1 region, the C-terminal side region (troponin T2) of rabbit skeletal troponin T was also involved in the exchange reaction of troponin in the bullfrog skeletal myofibrils. |
8070753 | [Transient and steady-state electroretinograms and visual evoked potentials to pattern and uniform-field stimulation in humans]. | I recorded simultaneously transient and steady-state electroretinograms (ERGs) and visual evoked potentials (VEPs) in response to pattern and uniform-field stimulation in 21 normal subjects, in order to study their physiological characteristics. ERGs and VEPs to pattern stimulation (P-ERGs and P-VEPs, respectively) showed different physiological features from those to uniform-field stimulation (U-ERGs and U-VEPs, respectively). With transient stimulation at a rate of 1Hz for both pattern and uniform-field stimulation, the b-wave latency of U-ERG tended to be shorter than that of P-ERG, while the P100 latency of P-VEP was significantly shorter than that of U-VEP. With steady-state stimulation at a rate of 4Hz for pattern stimulation and of 8Hz for uniform-field stimulation, the phase analysis revealed the first (1F) and the second (2F) harmonics as ponents for the U-ERG and U-VEP, while only 2F harmonic was a ponent for the P-ERG and P-VEP. The phase values of ponents were different each other, and the maximal amplitude of the ERGs was shown by the 1F of U-ERG while that of the VEPs was shown by the 2F of P-VEP. These results suggest that the pattern and uniform-field stimulation allows us to separate pattern (contrast)-specific responses from luminance-specific responses both in ERGs and VEPs. Four patients with optic atrophy showed normal U-ERG while all of them showed abnormal P-ERG, U-VEP and P-VEP except one, who showed normal U-VEP. P-ERGs and P-VEPs may offer the information about the proximal inner retinal layer (or the ganglion cells) and the contrast channel of the visual cortex. U-ERGs and U-VEPs may be useful in evaluating the functions of the preganglionic cell activity in the retina and the luminance channel of the visual cortex. Therefore, simultaneous recording of ERGs and VEPs to pattern and uniform-field stimulation under both transient and steady-state conditions increase the diagnostic value of electrophysiologic testing in the visual pathways. |
8070758 | [Radioligand binding assay of PHSA receptor on hepatocytes]. | The radioligand binding assay of PHSA receptor on hepatocytes of 7 adults is reported. The presence of PHSA receptor was demonstrated in all the 7 adults, though the individual difference of the Kds and binding capacities among them was distinct with a higher standard derivation. The mean values of the Kds and binding capacities were as follows: Kd1 = 9.6769 +/- 5.2767fm-2, C1 = 86.1468 +/- 46.4129fm/micrograms; Kd2 = 103.1810 +/- 56.4770fm-2, C2 = 261.5302 +/- 175.9094fm/micrograms. The Scatchard plot was a curve which indicated the PHSA receptor on the hepatocyte posed of two binding sites of different affinities and capacities. The possible mechanism and significance of PHSA receptor in the hepatotrophism are also discussed. |
8070759 | [Effects of zuzhongping on ischemic volume in the rat model of middle cerebral artery occlusion]. | Using the middle cerebral artery occlusion model, we studied the effects of Zuzhongping on experimental focal cerebral ischemia. Twenty-eight adult male Wistar rats were randomly divided into three groups: (1) Zuzhongping group (n = 9), (2) Saline control group (n = 10), and (3) Blank control group (n = 9). Group 1 and group 2 received via a gastric tube 1 1ml/kg/day of Zuzhongping and normal saline, respectively. The cerebral middle arteries on the right side of 28 rats were occluded with a bipolar electro-coagulater at sites 1-2 mm from the right olfactory nerve tract. Ischemic volumes were measured by an image analytic system when the cerebral ischemia had lasted 24 h. The results showed that the ischemic volume of Zuzhongping group was significantly smaller than that of group 2 and group 3, suggesting a protective effect of Zuzhongping. |
8070754 | Transfection of the bcr/abl oncogene into factor-dependent cells by electroporation: acquisition of autonomous proliferation. | In order to clarify the function of P210 bcr/abl oncogene in leukemogenesis, IL-3 dependent murine hematopietic cell line, FDC-P2, was transfected with the plasmid containing cDNA of P210 bcr/abl oncogene (pGD'210) or murine IL-3 (pcDmIL3) by electroporation. Four out of five pGDH210 transfected clones as well as FDC-P2 transfected with pcDmIL3, acquired autonomous proliferation (i.e. lost the requirement for IL-3 supplementation). The expression of bcr/abl oncogene was weak in one clone, which remained dependent on IL-3. Unlike pcDmIL3 transfectants, which secrete IL-3 into the supernatant, IL-3 was not demonstrated in the culture supernatant of pGD'210 transfected FDC-P2. These finding suggest that P210 bcr/abl oncogene is directly associated with autonomous proliferation, which is the first process of leukemogenesis. |
8070755 | Reactive hemophagocytic syndrome in childhood--frequent occurrence of atypical mononuclear cells. | Reactive hemophagocytic syndrome, which is characterized by systemic proliferation of benign hemophagocytic histiocytes, usually presents as an acute febrile illness with pancytopenia and hepatosplenomegaly. moner diseases associated with the syndrome are infection and malignant lymphoma. In this report, eight cases of reactive hemophagocytic syndrome occurring in infants and young children are described. Unlike the disease occurring in adults, there is frequent occurrence of atypical mononuclear cells both in the peripheral blood and bone marrow. The morphological spectrum of these atypical cells is however still within that seen in infectious mononucleosis, and their reactive nature is substantiated by their spontaneous disappearance and subsequent recovery of the patients. It is important to distinguish this reactive proliferation from the neoplastic cells of 'malignant histiocytosis' or malignant lymphoma, since cytotoxic drugs are not warranted for treatment of this non-neoplastic condition. |
8070760 | [Application of ORM1 phenotyping in forensic science]. | ORM1 is an important genetic marker for both parentage testing and personal identification in forensic science. We have examined the ORM1 phenotypes in the human serum and dried bloodstains using the ULPAGIF method. ORM1 phenotypes were successfully demonstrated from dried bloodstains stored at 4 degrees C and room temperature for up to twenty-four weeks. In bloodstains stored at 37 degrees C, the 100% of ORM1 phenotyping was no longer possible after 12 weeks. We examined 9 bloodstains stored at room temperature for one, two and three years, respectively. For the one-year-old bloodstains, all of the samples could be phenotyped correctly, for the two-year-old bloodstains 8 out of the 9 and for the three-year-old bloodstains 7 out of the 9 samples could be phenotyped correctly. The results have indicated that ORM1 is relatively stable, for it is tolerable toward high temperature and long duration. It was suggested that the bloodstains should be ultrasonicated before ULPAGIF, because the ultrasonication could elevate the detectable rate of ORM1 phenotypes from bloodstains. ORM1 phenotypes was performed in five disputed parentage cases. One of the alleged fathers was excluded. |
8070761 | [Chemiluminescent immunoassay for anti-granulocyte antibody IgG]. | In this paper is reported solid petitive chemiluminescent immunoassay (CLIA) for anti-granulocyte antibody (AGAb) IgG with N-(4-amiobytul)-N-ethylisoluminol (ABEI) labelled rabbit antibody IgG against peting with the analyte and ABEI-CoCl2-H2O2 as the chemiluminescent system. The absolute limit of detection was 3.0 x 10(-14) mol ABEI/tube. One hundred and thirty one individuals were divided into three groups: leukocytopenic group (n = 58), control group (n = 41) and normal group (n = 32). Chemiluminescent index (CLI) was used as the diagnostic criterion for AGAb in serum. The results showed that the positive rate of the leukocytopenic group was significantly higher than that of the control group (P < 0.005), and the sensitivity, specificity and accuracy of the method were 43.1%, 90.2% and 62.6%, respectively. |
8070762 | [Facial nerve repairs: a comparative experimental study of epineural and perineural techniques]. | This paper reports parative study results of perineural and epineural techniques in facial nerve (FN) transection injuries of 16 rabbits. We found little difference in recovery of FN function and histology between epineural and perineural repairs. Both epineural and perineural sutures on FN have not yet solved the problem of misdirection growth of nerve fibers. It is possible to cause the synkinesis movement by using epineural or perineural sutures in human FN. The epineural repair method should be used at the site of FN trunk which is present as a structure of mixed fasciolae giving out branches. The recovery degree of-eye-openings, ENoG and anastomotic pass-rate of regenerating myelinated axons could reflect the recovery degree of FN transection objectively. The three parameters show a parallel relationship. We suggest that either epineural suture or perineural suture should be carried out after FN transection injury. |
8070756 | Autologous bone marrow transplantation in adults with non-Hodgkin's lymphoma: a Southwest Oncology Group study. | Patients with non-Hodgkin's lymphoma (NHL) who fail conventional chemotherapy have a dismal e. Reports from single institutions utilizing high-dose chemoradiotherapy plus Autologous Bone Marrow Transplantation (ABMT) in this setting suggest three-year disease-free survival between 15-60 per cent. From 1985 to 1989 the Southwest Oncology Group performed a prospective multi-institutional study involving ABMT in relapsed/refractory NHL. Forty-five patients, ages 6-60 (median 38), with relapsed NHL were treated with high-dose cyclophosphamide (60 mg/kg/d x 2), total body irradiation (200 cGy/d x 6), and autologous unpurged bone marrow. Histologic subtypes included high grade lymphoma (10), intermediate grade lymphoma (33), and low grade lymphoma (2). Disease status pre-ABMT was sensitive relapse (16), resistant relapse (13), and untreated relapse (16). The actuarial three-year event-free survival and overall survival for all patients were 27 per cent and 38 per cent respectively. Causes of failure included regimen-related deaths (4), lack of response (10), or tumour progression (20) which occurred at a median of 5 months (1-22) post-ABMT and usually at previous sites of involvement. Response to salvage therapy pre-ABMT, a reflection of a tumour's biological behaviour, was the most important predictor of good e post-ABMT. This study confirms that a significant number of patients with recurrent NHL can achieve prolonged disease-free survival after ABMT. |
8070764 | [Descriptions of three new species of the genus Delia, anthomyiidae, diptera in Sichuan, China]. | Three new species of the genus Delia distributed in Mountain Emei and Huanglong Canyon have been identified and kept in our Parasitological Laboratory. 1. Delia taonura sp. nov. (Fig 1-3) male: Having no blunt bristles on the 5th sternite and long hairs on posterior part of the cercal plate, the new species is superficially similar to Delia longcauda (Strobl), but its round cercal plate and wider surstyle are different from those of the latter. Holotype male, Huanglong canyon, July 17, 1991, Coll. Deng Axiao. 2. Delia stenostyla sp. nov. (Fig 4-6) male: The new species is related to Delia nemostylata Deng, 1983, but its surstylus with an apical part expanding and curving forwards gradually, ependrium with short and straight hairs standing on the ventral side are different from those of the latter. Holotype male, Mountain Emei, Paratypes 224 male male, Minshan region, June, July 1982-1992, Coll. Deng Anxiao and Li Ling. 3. Delia conjugata sp. nov. (Fig 7-9) male: It is related to No. 2 mentioned above. The present species is different from No. 2 as follows: the surstyli with straightening on anterior border in proximate two thirds and expanding in distal one third, and the abdomen cylindrical. Holotype male, Paratypes 14 male male, Mountain Emei, July 1984, Coll. Deng Anxiao. |
8070763 | [Detection of isoferritin level in breast cancer tissue and serum]. | ELISA (double-determinant) was used to evaluate the isoferritin level in the breast cancer tissue. The isoferritin concentration was measured in cytosol extracts of 25 breast cancer tissues (BCT), 6 cancer surrounding tissues (CST) and 8 normal breast tissues (NBT). With the results of 16,023 +/- 15,732, 2467 +/- 1360 and 1382 +/- 647 ng/mcp (milligrams of ontosol protein), respectively. The isoferritin concentrations of BCT and CST were 11.6 and 1.8 times as much as that of NBT, and the differences were statistically significant (P < 0.001 and 0.05). The serum isoferritin level was also measured in 96 healthy persons and 68 breast cancer patients (mean 58.7 +/- 35.8 and 473.3 +/- 297.3 ng/ml) with the difference as big as 8.1 times. The results have demonstrated that the level of cytosol isoferritin in BCT is an important parameter of breast tissue malignance and may be also responsible for the serum isoferritin increase. Therefore we think that serum isoferritin may be used as a marker for early diagnosis of breast cancer. |
8070765 | [Characterization of receptor-mediated binding of 99mTc-NGA in vitro]. | This paper reports results of an assay of the binding of 99mTc-galactosylneoglycoalbumin (NGA) and plasma membranes of the rat liver in vitro. The data showed that 99mTc-NGA could be bound to the membrane receptor with high affinity. Specificity and saturability, and that the amount of membrane-bound 99mTc-NGA varied linearly with the amount of membrane within each reaction tube. The biphasic curve of scatchard plot revealed that 99mTc-NGA was bound to two sites of the receptor with different affinity and concentration (K1 8.4089 x 10(9) L/mol, R1 1.7350 x 10(-12) mol/mg); K2 2.0827 x 10(8) L/mol, R2 6.9530 x 10(-12) mol/mg). Therefore, the authors consider that 99mTc-NGA is a promising hepatic receptor agent for imaging. |
8070766 | [Quantitative study on cerebral motor cortex structure of kindling rat induced by coriaria lactone]. | Ten male Wistar rats were divided into two groups. The experimental rats were injected with subconvulsive dosage of coriaria lactone (1 mg/kg) intramuscularly every 3.5 days to induce kindling seizures. The controls were injected with normal saline. Cerebral motor cortex of kindling rats was taken at the time between seizures and layer V pared morphologically with that of the control. The number of neurons and neuroglias was counted from light micrographs. The numerical density and length fraction of boutons on the surface of pyramidal somata were measured from electron micrographs with MIAS 300 type image analyser. The number of synapses in neuropil was counted directly and the areal fraction of various constitute in neuropil was measured stereologically from EM photos. In the experimental rats, the number of neurons remained unchanged and the numerical density and length fraction of boutons on the surface of pyramidal somata showed no change, either. The number of synapses (or presynaptic terminals) decreased significantly in neuropil, but the areal fraction of synaptic terminals had no change and the areal fraction of dendrites and unmyelinated fibers decreased. The areal fraction of myelinated fibers increased significantly. The number of neuroglias and the areal fraction of neuroglial processes increased significantly in the experimental rats. The data suggest that the major morphological changes are manifested as a decline in the pyramidal ponents, especially dendritic spines, and the axons with its terminals from superficial neurons in motor cortex layer V of the kindling rats induced by coriaria lactone, besides the neurogliosis which is similar to that occurring in other long-term seizures. |
8070767 | [Synthesis of p-substituted benzoylaminobenzoic acid (methyl esters) and its differentiation induction in activities of human promyelocytic leukemia cells HL-60]. | Sixteen p-substituted benzoylaminobenzoic acids and their methyl esters were synthesized, of which nine were not found in literature. All of the pounds were evaluated for their differentiation induction in activities of human promyelotic leukemia cells HL-60. Compounds III1, III2, III4, and III5 possessed potential activities. The differentiation rate, of III4 and III5 was 70% respectively. But it was less than that of retinoic acid (97%). |
8070768 | [Immunohistochemical observation of anti-human hepatocellular carcinoma monoclonal antibody HL2 in cancers]. | Molecular weight of human hepatocellular carcinoma (HCC)-associated antigen-HL2 antigen was detected to be about 50,000 dalton by SDS-PAGE and Western blot. One hundred and twenty-seven paraffin sections of cancers and pathological liver tissue were tests by ABC immunohistochemical staining. MAb HL2 reacted with 62.7% HCC and also with 8 of the 10 stomach carcinomas but only with a few other digestive system carcinomas (pancreas carcinoma, rectum carcinoma and duodenum carcinoma) and hepatitis. MAb HL2 was negative in hepatocirrhosis and other tumors (vesica carcinoma, skin carcinoma, breast carcinoma, neurogliocytoma and carcinoma of the lung). The results suggest that MAb HL2 has values in diagnosis of HCC and differential diagnosis between HCC and other tumours. HL2 antigen might be a new tumor-associated antigen (TAA). Further study of HL2 antigen will significantly show the actions of TAA in the occurrence and development of tumor. |
8070769 | [Experimental study of Chinese Agkistrodon acutus venom in activation of rabbit platelets in vivo]. | Fourteen Albino rabbits, male and female, were allocated randomly into two groups: control group which had intravenous infusion of normal saline, and experimental group which had intravenous infusion of Chinese Agkistrodon Acutus venom (CAAV) 0.075 mg/kg. Platelet was reduced, plasma PF4 activity and 5-HT concentration increased, 5-HT content in platelets was reduced in the experimental group 10, 20, and 50 minutes after the infusion. It had a significant difference (P < pared with that in the control group. Platelets were aggregated into masses under electron microscope 10 minutes after the infusion of CAAV. The study has proved that blood platelets in rabbits are activated by Chinese Agkistrodon Acutus venom. |
8070770 | [Amplification of C-myc oncogene in squamous cell carcinoma of the larynx]. | C-myc amplification in 22 squamous cell carcinomas and 10 normal tissues (control) from the larynx was assessed by dot hybridization technique. Significant amplification of C-myc oncogene was found in malignant tumours pared with the normal tissues. The extent of amplification also correlated with advanced tumour stages. There was a significant increase in C-myc amplification in TNM stages III and IV pared with the stages I and II. These data suggested that C-myc oncogene might be activated by gene amplification and it might have a key role in determining the aggressiveness of laryngeal carcinoma. |
8070772 | [Preparation of membrane proteins of Trichinella spiralis larva and application of them in detection with ELISA]. | Membrane proteins of muscle larva of Trichinella spiralis (T.s) were isolated by using the non-ionic detergent Triton X-114. At least ponents in the membrane proteins were separated with SDS-PAGE and then silver nitrate stain. The bands of them were located between 99-18kd MW level. The MW of chief bands were 94, 90, 47, 32 and 28kd. The sensitivity and specificity of these proteins were determined with ELISA. They didn't cross react with sera of rabbits infected with Toxocara canis (T. c), Schistosoma japonicum (S. j), Paragonimus skr jabini (P. s) and Clonorchis sinensis (C. s). Their sensitivity is the same as and their specificity is higher than those of ES antigens and cuticular antigens obtained with cetultrimethylamonium bromide (CTAB) from muscle larva of Trichinella spiralis. |
8070771 | [Anti-implantation action of nylestriol and its effect on endometrium in rabbits]. | The anti-implantation action of nylestriol in rabbits was studied. Using the method of arresting mitosis by injection of colchicine, we detected the mitosis frequency of endometrial cells. The activities of carbonic anhydrase (CAH), A1P and PAS reaction were observed under light bined with the histochemical method and microscopic autoexposure control device. The results were as follows: 1. Giving nylestriol orally to rabbits on day 1 of pregnancy produced an obvious anti-implantation effect; 2. The number of mitosis cells in glandular epithelium and stroma of the endometrium in the treatment group was less than that in the control group (P < 0.05); and 3. Compared with the control group, the activities of CAH and A1P, and glycogen content in the endometrium decreased significantly in the treatment group (P < 0.05). The result suggests that nylestriol may prevent the implantation of blastocyst by disturbing decidulization of the endometrium. |
8070773 | [Changes in cell spreading area and cell surface morphology of Tca8113 line affected by fibronectin]. | Morphometric changes in cell spreading area and morphological alternation in cell surface of human tongue squamous cancer line Tca8113 on rat-tail collagen substrata supplemented with different concentration of FN and/or anti-FN serum were quantified and observed with cell culture technique as well as light and scanning electron microscopes. It was found that FN could increase the cell spreading area and also area of lamellar cytoplasm of Tca8113 cells on collagen substrata, and that cells grown on FN-collagen substrata tended to flatten out, stretch out more filopodia, and sink more deeply into the substrata with the FN concentration. The results indicated that FN might relate closely to certain stages in the process of tumor invasion. |
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