bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Acetylcholine on Sodium‐Dependent High‐Affinity Glutamate Transport in Rat Striatal Homogenates
Authors: Kerkerian Lydia , Nieoullon André
Published: December 2006

Abstract: Incubation of rat striatal tissue in the presence of acetylcholine, carbachol, oxotremorine, or nicotine results in a significant decrease in the sodium‐dependent high‐affinity glutamate uptake (HAGU). The cholinergic inhibitory effect on glutamate transport is no more detectable in the presence of atropine, a cholinergic receptor antagonist. These data support the hypothesis that glutamatergic nerve ending activity in the striatum is modulated by cholinergic neurons. The effects would in volve both muscarinic and nicotinic presynaptic receptors located on the corticostriatal glutamatergic terminals.
Effects of In Vivo Administration of Kainic Acid on the Extracellular Amino Acid Pool in the Rabbit Hippocampus
Authors: Lehmann Anders , Isacsson Helena , Hamberger Anders
Published: December 2006

Abstract: The effect of local administration of kainic acid in the rabbit hippocampus was studied; the hippocampus was perfused continuously in the freely moving animal with an implanted 0.3‐mm dialysis fiber. The pattern of endogenous amino acids in the perfusate, reflecting extracellular amino acids, was monitored with liquid chromatography separation and fluorimetric detection of amino acid derivatives. Kainic acid was included in the perfusion medium for up to 70 min at 0.1–1.0 mM and, with time, induced epileptiform activity. Endogenous glutamic acid, taurine, and phosphoethanolamine levels were increased selectively at the lower perfusion concentrations of kainic acid. Long perfusion periods with higher concentrations increased the levels of virtually all amino acids. Perfusion of the hippocampus with depolarizing concentrations of potassium gave an amino acid response partly similar to that seen with kainic acid treatment. However, one notable difference between the two responses was that the extracellular concentration of glutamine, although not influenced by kainic acid, was significantly decreased after high potassium concentrations. These results confirm previous notions that kainic acid has a primarily excitatory effect, one manifestation of this effect being the release of glutamic acid.
Effect of Acute and Chronic Cholinesterase Inhibition with Diisopropylfluorophosphate on Muscarinic, Dopamine, and GABA Receptors of the Rat Striatum
Authors: Sivam S. P. , Norris J. C. , Lim D. K. , Hoskins B. , Ho I. K.
Published: December 2006

Abstract: The effects of acute and chronic administration of diisopropylfluorophosphate (DFP) to rats on acetylcholinesterase (AChE) activity (in striatum, medulla, diencephalon, cortex, and medulla) and muscarinic, dopamine (DA), and γ‐aminobutyric acid (GABA) receptor characteristics (in striatum) were investigated. After a single injection of (acute exposure to) DFP, striatal region was found to have the highest degree of AChE inhibition. After daily DFP injections (chronic treatment), all brain regions had the same degree of AChE inhibition, which remained at a steady level despite the regression of the DFP‐induced cholinergic overactivity. Acute administration of DFP increased the number of DA and GABA receptors without affecting the muscarinic receptor characteristics. Whereas chronic administration of DFP for either 4 or 14 days reduced the number of muscarinic sites without affecting their affinity, the DFP treatment caused increase in the number of DA and GABA receptors only after 14 days of treatment; however, the increase was considerably lower than that observed after the acute treatment. The in vitro addition of DFP to striatal membranes did not affect DA, GABA, or muscarinic receptors. The results indicate an involvement of GABAergic and dopaminergic systems in the actions of DFP. It is suggested that the GABAergic and dopaminergic involvement may be a part of a compensatory inhibitory process to counteract the excessive cholinergic activity produced by DFP.
Effects of Postnatal Trimethyltin or Triethyltin Treatment on CNS Catecholamine, GABA, and Acetylcholine Systems in the Rat
Authors: Mailman Richard B. , Krigman Martin R. , Frye Gerald D. , Hanin Israel
Published: December 2006

Abstract: The effects on brain neurochemistry of two neurotoxic tin compounds, trimethyltin (TMT) hydroxide and triethyltin (TET) sulfate, were examined. Long‐Evans rats were treated with TMT hydroxide (1 mg/kg, i.p.) on alternate days from day 2 to 29 of life. These treatments caused a weight deficit of 10–20% by the time the animals were killed on day 55 by head‐focused microwave irradiation. These TMT treatments are known to cause severe neuronal loss in the hippocampus and lesser damage in other brain regions. Accordingly, the concentration of γ‐aminobutyric acid (GABA) was decreased in the hippocampus; however, acetylcholine and choline concentrations were unaffected. These data suggest that TMT‐induced effects on GABA systems are greater than that due simply to generalized neuronal loss. The TMT treatments also caused a significant decrease in dopamine concentrations in the striatum, but did not alter the concentrations of dihydroxyphenylacetic acid or homovanillic acid, the acidic metabolites of dopamine. Conversely, concentrations of dopamine and norepinephrine in the brain stem and norepinephrine in the cerebellum were not altered. Despite reports in the literature of TMT‐induced neuronal damage in areas of the cortex, no effects on GABA, acetylcholine, or choline levels were found in the cortical areas examined, or in the hypothalamus. TET sulfate (0.3 mg/kg/day) was administered for 6 consecutive days of every week during days 2–29 of life. This dose is lower than that needed to cause intramyelin edema, yet it does result in long‐term behavioral changes. Despite this, no changes in the concentration of any of the measured neurotransmitters or their metabolites were detected. In concert, these data demonstrate that neurochemical methods should not be used as neurological “screens,” but rather to define specific mechanisms suggested by detailed behavior, pharmacological, and/or physiological studies.
Proteins of the Extracellular Fluid of Mouse Brain: Extraction and Partial Characterization
Authors: Hofstein Raphael , Hesse Gary , Shashoua Victor E.
Published: December 2006

Abstract: An extraction procedure for the isolation of proteins from the brain extracellular fluid (ECF) was developed and applied to studies of the ECF components of mouse brain. Perfused intact brains were incubated in an isotonic medium for periods of up to 2 h at 0°C to allow the release of ECF into the medium without disruption of the integrity of the tissue. The validity of the extraction procedure was established by (a) the fact that the total yield of ECF proteins was constant per unit weight of brain tissue, (b) the absence of tyrosine hydroxylase, an enzyme marker of the cytoplasmic fraction, from the extracts, and (c) the distinctive features of the one‐ and two‐dimensional gel electrophoretic patterns of ECF proteins as compared with those of the cytoplasmic and membrane fractions. The results indicate that the extracellular fluid of mouse brain contains a mixture of proteins with a wide distribution of molecular weights (10,000–100,000 daltons) at a concentration level of about 0.3%.
High Levels of Brain Dolichols in Neuronal Ceroid‐Lipofuscinosis and Senescence
Authors: Kin N. M. K. Ng Ying , Palo J. , Haltia M. , Wolfe L. S.
Published: December 2006

Abstract: Dolichols as unesterified alcohols were identified as significant components of lipid extracts from storage cytosomes isolated post‐mortem from the brains of patients with the infantile, late infantile, and juvenile types of neuronal ceroid‐lipofuscinosis (NCL). Very small amounts of dolichols were present in the corresponding subcellular fractions of non‐NCL brains. The nuclear fraction from NCL cerebral cortex contained the highest dolichol content expressed per milligram protein or lipid, whereas the crude mitochondrial fraction was the richest in normal brain. Highly significant elevations of dolichol levels were found in human cerebral cortex of patients with NCL and Alzheimer's disease compared with age‐matched controls, but the levels were normal in Pick's disease. In human non‐NCL cerebral cortex, dolichols increased from 16 μg/g at age 5 to over 200 at age 81. Rat cerebral cortex showed a similar progressive increase in dolichol content with age. The high dolichol values in NCL, Alzheimer's disease, and senescence appears to be related to the increase of lipofuscin in brain. This is the first time a uniform biochemical abnormality has been found in all childhood forms of NCL, but the enzyme defect is still unidentified. It may lie on pathways where dolichols and retinyl compounds are recycled in Golgi membranes and derived organelles during the biosynthesis of glycoproteins.
Striatal Tissue Preparation Facilitates Early Sampling in Microdialysis and Reveals an Index of Neuronal Damage
Authors: Devine Darragh P. , Leone Paola , Wise Roy A.
Published: December 2006

Abstract: Injury‐induced efflux of dopamine was compared between two microdialysis preparations. Rats were implanted with guide cannulae 5–10 days prior to microdialysis experiments. In one group, ventral striatal tissue was punctured with stainless steel obturators that remained in place until the day of the experiment. In the other group, the tissue was not punctured until the microdialysis probes were inserted. Rats from each group were dialyzed with calcium‐free artificial extracellular fluid or tetrodotoxin 4 h after probe insertion. In the rats with previously punctured tissue, calcium depletion reduced dialysate dopamine concentrations to 8% of baseline. Dialysis with tetrodotoxin reduced dopamine concentrations to less than 1% of baseline. In the rats with freshly punctured tissue, dopamine concentrations were reduced only to 50% of baseline levels by calcium depletion and to 30% during dialysis with tetrodotoxin. Thus, penetration of the tissue prior to testing can significantly reduce the acute injury‐induced efflux of dopamine. Further, a significant correlation was found between baseline 3,4‐dihydroxy‐phenylacetic acid/dopamine ratios and the efficacy of tetrodotoxin in reducing dialysate dopamine concentrations. Thus, basal 3,4‐dihydroxyphenylacetic acid/dopamine ratios appear to provide an index of the amount of injury‐induced dopamine efflux following probe insertion.
Interleukin‐2 Modulates Evoked Release of [3H]Dopamine in Rat Cultured Mesencephalic Cells
Authors: Alonso Richard , Chaudieu Isabelle , Diorio Josie , Krishnamurthy Anuradha , Quirion Rémi , Boksa Patricia
Published: December 2006

Abstract: Mesencephalic cell cultures were used as a model to investigate the effects of interleukin‐2 (IL‐2) on evoked release of [3H]dopamine ([3H]DA) and γ‐[3H]‐aminobutyric acid ([3H]GABA). At low concentrations (10−13‐10−12M), IL‐2 potentiated [3H]DA release evoked by the excitatory amino acids N‐methyl‐D‐aspartate (NMDA) and kainate, whereas higher IL‐2 concentrations (10−9‐10−8M) had no effect. IL‐2 (10−14‐10−8M) modulated K+‐evoked [3H]DA release in a biphasic manner, with low concentrations (10−12‐10−11M) of IL‐2 potentiating and higher concentrations (10−9‐10−8M) inhibiting K+‐induced [3H]DA release. IL‐2 (10−14‐10−8M) by itself failed to alter spontaneous [3H]DA release. The inhibition by IL‐2 of K+‐evoked [3H]DA release was reversible and not due to neurotoxicity, as preexposure to IL‐2 (10−8M) had no significant effect on the subsequent ability of dopaminergic cells to take up and to release [3H]DA. Under our experimental conditions, IL‐2 (10−8 M) did not alter Ca2+‐independent [3H]GABA release evoked by either K+ or NMDA. The results of this study indicate that IL‐2 is able to potentiate [3H]DA release evoked by a number of different stimuli, including K+ depolarization and activation of both NMDA and non‐NMDA receptor subtypes in mesencephalic cell cultures. IL‐2 is active at very low concentrations, a finding that indicates a potent effect of IL‐2 on dopaminergic neurons and implicates a physiological role for this cytokine in the modulation of DA release.
Activation of Mitogen‐Activated Protein Kinase by Epidermal Growth Factor in Hippocampal Neurons and Neuronal Cell Lines
Authors: Tucker Marcy S. , Eves Eva M. , Wainer Bruce H. , Rosner Marsha Rich
Published: December 2006

Abstract: Epidermal growth factor (EGF) functions in a bimodal capacity in the nervous system, acting as a mitogen in neuronal stem cells and a neurotrophic factor in differentiated adult neurons. Thus, it is likely that EGF signal transduction, as well as receptor expression, differs among various cell types and possibly in the same cell type at different stages of development. We used hippocampal neuronal cell lines capable of terminal differentiation to investigate changes in EGF receptor expression, DNA synthesis, and stimulation of mitogen‐activated protein (MAP) kinase by EGF before and after differentiation. H19‐7, the line that was most representative of hippocampal neurons, was mitogenically responsive to EGF only before differentiation and increased in EGF binding after differentiation. MAP kinase was stimulated by EGF in both undifferentiated and differentiated cells, as well as in primary hippocampal cultures treated with either EGF or glutamate. These results indicate that the activation of MAP kinase by EGF is an early signaling event in both mitotic and postmitotic neuronal cells. Furthermore, these studies demonstrate the usefulness of hippocampal cell lines as a homogeneous neuronal system for studies of EGF signaling or other receptor signaling mechanisms in the brain.
Growth‐Promoting Action of Adenosine‐Containing Dinucleotide on Neuroblastoma Cells: Detection of Adenosine‐Cytidine Dinucleotide (ApCp) in Neurofibroma (NF1) Extracts
Authors: Hotta Taeko , Asai Kiyofumi , Takeda Naohito , Yoshizumi Hideo , Tatematsu Akira , Nakanishi Keiko , Eksioglu Yaman Z. , Isobe Ichiro , Kato Taiji
Published: December 2006

Abstract: Neurofibroma type 1 tissue was investigated for the presence of growth‐promoting activity on human neuroblastoma cells. The activity was isolated by gel filtration and reversed‐phase column chromatographs from neurofibroma type 1 extracts. An adenosine‐containing dinucleotide (adenylyl(3′‐5′)cytidine‐3′‐phosphate) was identified as one of the major components of the activities by its enzymatic fragmentation and liquid chromatography/mass spectrometry. Synthetic adenosine‐containing dinucleotide derivatives such as cytidyl(3′‐5′)adenosine, cytidyl(2′‐5′)adenosine, adenylyl(3′‐5′)cytidine, and adenylyl(2′‐5′)cytidine showed a similar action. Cytidyl(3′‐5′)adenosine, cytidyl(2′‐5′)adenosine, and adenylyl(2′‐5′)cytidine, which are able to release a free adenosine through enzymatic hydrolysis, in particular elicited a strong activity corresponding to that of adenosine with the highest action. These results suggest that neuroblastoma cells are able to use adenosine‐containing dinucleotides as well as mononucleotides for their survival and proliferation.
Allosteric Modulation of [3H]CGP 39653 Binding by Glycine in Rat Brain
Authors: Mugnaini Manolo , Giberti Alessandra , Ratti Emiliangelo , van Amsterdam Frank Th. M.
Published: December 2006

Abstract: D,L‐(E)‐2‐Amino‐4‐propyl‐5‐phosphono‐3‐pen‐tenoic acid (CGP 39653). a new, high‐affinity, selective NMDA receptor antagonist, interacts with rat cortical membranes in a saturable way and apparently to a single binding site, with a KD of 10.7 nM and a receptor density of 2.6 pmol/mg of protein. Displacement analysis of [3H]CGP 39653 binding shows a pharmacological profile similar to that reported for another NMDA antagonist, 3‐[(±)‐2‐carboxypiperazin‐4‐yI]propyl‐1‐phosphonic acid (CPP). Glycine, however, is able to discriminate between the two ligands; in fact, it does not affect [3H]CPP binding but inhibits [3H]CGP 39653 binding in a biphasic way. D‐Serine, another agonist at the strychnine‐insensitive glycine binding site of the NMDA receptor complex, inhibits [3H]CGP 39653 binding in the same way as glycine, with a potency that correlates with its binding affinity at the glycine site. In addition, 7‐chlorokynurenic acid, an antagonist at the glycine site, is able to reverse the displacement of [3H]CGP 39653 by glycine in a dose‐dependent manner. Furthermore, the dissociation rate constant of [3H]CGP 39653 is enhanced in the presence of glycine, whereas the presence of NMDA receptor ligands does not modify the rate of dissociation of [3H]CGP 39653 from the receptor. These results indicate that part of the binding of the NMDA antagonist CGP 39653 can be potently modified by glycine through an allosteric mechanism, and suggest the existence of two antagonist preferring NMDA receptor subtypes that are differentially modulated through the glycine binding site.
B‐50/GAP‐43 Binds to Actin Filaments Without Affecting Actin Polymerization and Filament Organization
Authors: Hens Jacques J. H. , Fabio Benfenati  , Nielander Henk B. , Valtorta Flavia , Gispen Willem Hendnk , De Graan Pierre N. E.
Published: December 2006

Abstract: To investigate a possible function of the nervous tissuespecific protein kinase C substrate B‐50/GAP‐43 in regulati of the dynamics of the submembranous cytoskeleton. we studii the interaction between purified 6–50 and actin. Both the phosphorylated and dephosphorylated forms of 8–50 cosedi‐mented with filamentous actin (F‐actin) in a Ca2+‐independent manner. Neither 6–50 nor phospho‐6–50 had any effect on the kinetics of actin polymerization and on the critical concentration at steady state, as measured using pyrenylated actin. tight scattering of F‐actin samples was not increased in the presence of 550, suggesting that 550 does not bundle actin filaments. The number of actin filaments, determined by [3H]cytochalasin B binding, was not affected by either phospho‐ or dephospho‐B‐50, indicating that 550 has neither a severing nor a capping effect. These observations were confirmed by electron microscopic evaluation of negatively stained F‐actin samples, which did not reveal any structural changes in the actin meshwork on addition of 6–50, We conclude that 6–50 is an actin‐binding protein that does not directly affect actin dynamics.
Reduction in Glial Fibrillary Acidic Protein mRNA Abundance Induced by (—)‐Deprenyl and Other Monoamine Oxidase B Inhibitors in C6 Glioma Cells
Authors: Li Xin‐Min , Qi Jin , Juorio Augusto V. , Boulton Alan A.
Published: December 2006

Abstract: Gliosis is commonly observed in the CNS following tissue damage, and it also occurs in aging and in many neurodegen‐erative diseases. Glial fibrillary acidic protein (GFAP) accumulation is a prominent feature of astrocytic gliosis. An inhibition or delay in GFAP synthesis could mitigate scar formation and thus reduce the formation of a physical barrier. The consequence of this would be to allow neurons and oligodendrocytes to reestablish a functional environment. (—)‐Deprenyl, a specific monoamine oxidase (MAO) B inhibitor, has been used as an effective antipar‐kinsonian drug, and it has been reported to possess neuroprotective and neurorescue properties. Using northern and slot blots to detect GFAP mRNA in C6 glioma cells, we have demonstrated that (—)‐deprenyl decreases the abundance of GFAP mRNA in a time‐ and dose‐dependent manner. The effect seems to be specific to MA0 B inhibitors because (+)‐deprenyl and clorgyline exhibit no effect. This study indicates therefore that (‐)‐deprenyl may be useful for regulating astrogliosis following CNS injury as well as in some neurodegenerative diseases.
Reduction of methamphetamine‐induced sensitization and reward in matrix metalloproteinase‐2 and ‐9‐deficient mice
Authors: Mizoguchi Hiroyuki , Yamada Kiyofumi , Niwa Minae , Mouri Akihiro , Mizuno Tomoko , Noda Yukihiro , Nitta Atsumi , Itohara Shigeyoshi , Banno Yoshiko , Nabeshima Toshitaka
Published: December 2006

Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) function to remodel the pericellular environment. Their activation and regulation are associated with synaptic physiology and pathology. Here, we investigated whether MMP‐2 and MMP‐9 are involved in the rewarding effects of and sensitization to methamphetamine (METH) in animals, in which the remodelling of neural circuits may play a crucial role. Repeated METH treatment induced behavioural sensitization, which was accompanied by an increase in MMP‐2 and MMP‐9 activity in the brain. In MMP‐2‐ and MMP‐9‐deficient mice [MMP‐2‐(–/–) and MMP‐9‐(–/–)], METH‐induced behavioural sensitization and conditioned place preference, a measure of the rewarding effect, as well as METH‐increased dopamine release in the nucleus accumbens (NAc) were attenuated compared with those in wild‐type mice. In contrast, infusion of purified human MMP‐2 into the NAc significantly potentiated the METH‐increased dopamine release. The [3H]dopamine uptake into striatal synaptosomes was reduced in wild‐type mice after repeated METH treatment, but METH‐induced changes in [3H]dopamine uptake were significantly attenuated in MMP‐2‐(–/–) and MMP‐9‐(–/–) mice. These results suggest that both MMP‐2 and MMP‐9 play a crucial role in METH‐induced behavioural sensitization and reward by regulating METH‐induced dopamine release and uptake in the NAc.
Nine polymorphic microsatellite markers in Crepis sancta (Asteraceae)
Authors: DUBOIS MARIE‐PIERRE , DORNIER ANTOINE , JARNE PHILIPPE , CHEPTOU PIERRE‐OLIVIER
Published: December 2006

We describe nine new variable di‐ and trinucleotide microsatellites in the plant Crepis sancta, as well as conditions for multiplexing and simultaneous genotyping sets of loci. Their variability was assessed in four populations. Four to 33 alleles were detected per locus; two to 23 alleles per population. Significant deviations from Hardy–Weinberg equilibrium could be attributed either to a mating system involving partial selfing or to null alleles. Genetic differentiation over all loci was significant among the four populations studied. These markers will constitute an efficient tool for investigating dispersal patterns in fragmented landscapes. Cross‐species amplification provided few loci variability in three other Crepis species (C. pulcra, C. foetida and C. rubra).
Cosmetic camouflage
Authors: Antoniou Christina , Stefanaki Christina
Published: December 2006

Although many skin conditions are amenable to treatment, on certain occasions dermatology and plastic surgery have not much to offer and patients are left with disfigurements. Cosmetic camouflage is a therapy that has been developed to alleviate the suffering of those who have been disfigured by a congenital or an acquired lesion and who have no other choice than living with their deformity.
Photoprotection: where do we stand?
Authors: Nicolaidou Electra , Stefanaki Christina , Katsambas Andreas D
Published: December 2006

Ultraviolet sun radiation can cause several deleterious effects on the skin, including photoaging and carcinogenesis. Physical protection and sunscreens are currently the two main types of photoprotection. Overall, people seem informed about the dangers of sun exposure, but sometimes they are not willing to implement the right sun‐protection measures. Sunscreens are reported to be the most frequently used method worldwide, but they cannot substitute physical protection and a proportion of people do not apply them correctly. Public campaigns, together with fashion and the right role models, can still offer a lot in persuading people to change their habits towards a more sun‐protected life.
CD34‐positive eruptive fibromas
Authors: Pursley Holly Gluth , Williford Phillip M. , Groben Pam A. , White Wain L.
Published: December 2006

The list of entities comprising a proliferation of CD34 (+) spindle cells continues to grow. Described, herein, is a patient who had an indolent eruption of scattered papules composed of CD34 (+) spindle cells, beginning in adolescence.

An 18‐year‐old female patient presented with asymptomatic, tan/brown papules over the neck, chest, and proximal extremities. They appeared 6 years previously and had slowly increased in number. Biopsy from the neck showed a proliferation of plump spindle cells, associated with delicate collagen, in the upper reticular dermis. No atypia nor mitotic figures were present. The spindle cells were negative for S‐100, muscle actins, and Factor XIIIa, but stained intensely with CD34. This unusual mesenchymal proliferation of CD34 (+) apparent dermal dendrocytes did not have the storiform pattern, short fascicles, nor mitotic figures of DFSP. The completely negative muscle markers helped to exclude dermatomyofibroma, and no morphological evidence of vasoformative differentiation was seen. The clinical picture militated against solitary fibrous tumor. These eruptive tumors are benign and thought to represent a distinctive fibroma produced by proliferated CD34 (+) stromal cells.
Apoptosis and cellular proliferation in human epidermal squamous cell neoplasia
Authors: Makino Takafumi , Tatebe Shigeru , Goto Akira , Mihara Motoyuki , Ito Hisao
Published: December 2006

We examined cell loss (apoptosis) and proliferation in a histopathological spectrum of epidermal squamous cell neoplasia, including 11 cases of solar keratosis (SK), 18 Bowen's diseases (BD) and 19 invasive squamous cell carcinomas (SCC). Apoptotic and proliferative cells were determined by terminal deoxynucleotidyl transferase (TdT)‐mediated dUTP‐digoxigenin nick end labeling (TUNEL) and by the detection of nuclear antigen Ki‐67, respectively. Few apoptotic cells were observed in normal epidermis, while TUNEL index (TI; percentage of TUNEL‐positive cells) was highest for SCCs, followed by BDs and SKs, in the order given. Although the mean Ki‐67 index did not differ between SCCs and BDs. both disease types showed a significantly higher index than the SKs. Of SCCs, both TI and Ki‐67 index values were significantly higher in poorly than in well differentiated carcinomas. TI was significantly higher in SCCs without P53 immunohistochemical expression than in SCCs with P53 expression, while TI and Ki‐67 indices did not correlate with P53 expression in the SKs and BDs. These results suggest that apoptosis reflects not only cell loss, but also proliferative activity in the epidermal neoplastic lesions.
Expression of moesin and its associated molecule CD44 in epithelial skin tumors
Authors: Ichikawa Takeshi , Masumoto Junya , Kaneko Miwako , Saida Toshiaki , Sagara Junji , Taniguchi Shun'ichiro
Published: December 2006

Moesin, one of the ERM (ezrin; radixin; moesin) family members, is directly associated with the cytoplasmic domain of CD44, which is now thought to be related to the metastatic potential of tumor cells. Using immunohistochemistry we investigated the expression of moesin in normal epidermis and various kinds of epithelial skin tumors: squamous cell carcinoma, verrucous carcinoma, Bowen's disease, solar keratosis, keratoacanthoma, basal cell carcinoma, and extramammary Paget's disease. Normal skin showed positive epidermal staining for moesin with the exception of the stratum corneum. The expression of moesin varied with the type of skin tumor. In basal cell carcinoma, Bowen's disease, and extramammary Paget's disease, moesin expression was either faint or negative. In contrast to Bowen's disease, invasive squamous cell carcinoma showed more intense and heterogeneous staining of the cytoplasm and the cell membrane. Verrucous carcinoma was weakly positive, with a tendency for the moesin to be distributed in the cell membrane. The staining pattern of moesin varied among the different kinds of epithelial skin tumors, and its expression was generally similar to that of the standard form of CD44. These results suggest that moesin is closely inter‐related with CD44 in epithelial skin cells as seen in other cellular systems, and that the variable pattern of moesin staining among the skin tumor cells could reflect expression disorders associated with the transformation.
MAGNETIC RESONANCE IMAGING CHARACTERISTICS OF PERIPHERAL NERVE SHEATH TUMORS OF THE CANINE BRACHIAL PLEXUS IN 18 DOGS
Authors: KRAFT SUSAN , EHRHART E. J. , GALL DAVID , KLOPP LISA , GAVIN PATRICK , TUCKER RUSS , BAGLEY ROD , KIPPENES HEGE , DEHAAN CONSTANCE , PEDROIA VINCE , PARTINGTON BETH , OLBY NATASHA
Published: December 2006

Magnetic resonance imaging (MRI) examinations from 18 dogs with a histologically confirmed peripheral nerve sheath tumor (PNST) of the brachial plexus were assessed retrospectively. Almost half (8/18) had a diffuse thickening of the brachial plexus nerve(s), six of which extended into the vertebral canal. The other 10/18 dogs had a nodule or mass in the axilla (1.2–338 cm3). Seven of those 10 masses also had diffuse nerve sheath thickening, three of which extended into the vertebral canal. The majority of tumors were hyperintense to muscle on T2‐weighted images and isointense on T1‐weighted images. Eight of 18 PNSTs had only minimal to mild contrast enhancement and many (13/18) enhanced heterogeneously following gadolinium DTPA administration. Transverse plane images with a large enough field of view (FOV) to include both axillae and the vertebral canal were essential, allowing in‐slice comparison to detect lesions by asymmetry of structures. Higher resolution, smaller FOV, multiplanar examination of the cervicothoracic spine was important for appreciating nerve root and foraminal involvement. Short tau inversion recovery, T2‐weighted, pre and postcontrast T1‐weighted pulse sequences were all useful. Contrast enhancement was critical to detecting subtle diffuse nerve sheath involvement or small isointense nodules, and for accurately identifying the full extent of disease. Some canine brachial plexus tumors can be challenging to detect, requiring a rigorous multiplanar multi‐pulse sequence MRI examination.
Indorenate Improves Motor Function in Rats with Chronic Spinal Cord Injury
Authors: Bravo Guadalupe , Ibarra Antonio , Guizar‐Sahagún Gabriel , Rojas Guillermo , Hong Enrique
Published: December 2006

Abstract:  The effect of indorenate (5‐methoxytryptamine, β‐methyl carboxylate hydrochloride), a 5‐HT1A agonist, was investigated on the motor performance of rats with chronic spinal cord injury. Four months after a ninth thoracic vertebrae spinal cord contusion, 29 rats were randomly allocated into two groups: saline solution and indorenate‐treated animals with daily doses incremented at weekly intervals. The locomotor performance of all rats was measured by the Basso, Beattie, and Bresnahan (BBB) rating scale. The results showed that at the end of the treatment, the motor activity of indorenate group was significantly better than that presented by saline solution group. The 80% of indorenate, (against 15% of saline solution) did not show detriment on motor activity. When we analysed the motor activity of rats with basal BBB lower than 10, a significant improvement of motor recovery in indorenate‐treated animals was observed. The benefits observed in locomotor function at low doses followed by increasing doses could be associated with pharmacological treatment by indorenate, a well‐known 5‐HT1A receptor agonist. Our results suggest a potential mechanism by which serotonergic agents may improve motor function in rats with chronic spinal cord injury.
Fundamental Mechanical Aspects of Thin‐Film Lubrication
Authors: Blok Harmen
Published: December 2006

The paper highlights an extensive correlational study of the experimental evidence obtainable from literature on thin‐film lubrication. According to the widely varying nature of the various cases of thin‐film lubrication, this evidence is highly fragmentary and often seemingly incoherent. The main objective of the paper is to combine the evidence available into a coherent core of information on the fundamental mechanical aspects of thin‐film lubrication. From this core, continued research can profitably radiate in several directions, in the improvement of lubricants and the design of lubricated machine parts, for example. The objective set could be attained by introducing some unifying thoughts and theories in which dimensional analysis played an important role.

The main conclusions, referring to the main and the supplementary theme, respectively, are: (1) any definitions of “oiliness” are inadequate that specify viscosity (even if its variations with temperature and pressure are included) as the one and only bulk property whose effects are to be eliminated in the measurement of “oiliness” as a surface‐active property, and a considerable improvement can be achieved by replacing the word “viscosity” in such definitions by the term “bulk properties of the lubricant and of the rubbing bodies”; and, (2) the core of information obtained can be turned to future advantage in settling the important question, “What are the limits inherent in hydrodynamic load‐carrying capacity?”
Influence of Roughness and Oxidation on Wear of Lubricated Sliding Metal Surfaces
Authors: Davies C. B.
Published: December 2006

Measurements have been made, at room temperature, of the wear of a flat steel annulus flooded with lubricant and rotating about its axis in a horizontal plane pressed against the lower horizontal end of a small (1 mm. diameter) stationary, vertical, cylindrical pin. It was found that steady reproducible wear rates could be obtained only when one of the surfaces was relatively soft and other extremely hard and comparatively rough.
OBSERVATIONS ON PHARMACOLOGICAL AGENTS RECENTLY SUGGESTED FOR MULTIPLE SCLEROSIS
Authors: Marks Morton
Published: December 2006

Summary
THE MANIFESTATIONS AND DIAGNOSIS OF BABESIA INFECTIONS
Authors: Malherbe W. D.
Published: December 2006

In spite of a considerable literature on the Babesia infections of animals, there are comparatively few references to atypical manifestations of the disease. The existing references are reviewed in this paper. They include cases manifested by ocular, respiratory, digestive, nervous, and rheumatic symptoms.

Since the causal agents are not always demonstrable in smears of the peripheral blood, and since the disease picture can be so very variable, the criteria of diagnosis are laid down and discussed. A number of cases studied at the Onderstepoort Veterinary Institute, Onderstepoort, Union of South Africa, are described according to the body systems mainly involved. Respiratory symptoms include a range from simple catarrhs to intense dyspnea simulating pneumonia. A striking group is made up by the involvement of the circulatory system, presenting such symptoms as severe ascites, asymmetrical edemas, and purpuric lesions. In the nervous system, Babesia infections are represented in animals by the manifestation of epileptiform fits, aberrations of the gait, abnormal actions and postures, and peripheral nerve palsies. Enteritis and gastritis indicate involvement of the digestive system.

The pathogenesis of the atypical lesions is discussed in considerable detail in the light of the pathological and clinicopathological changes that take place in the babesioses. These changes include blocking of the capillaries by agglomerations of parasitized red blood corpuscles with consequent local tissue anoxia and intoxication, anemia, hypoalbuminemia, degeneration of the liver and kidneys, capillary fragility, and marked coagulation defects of the blood.

In all these changes and manifestations there is a close parallel with those encountered in malaria from time to time, particularly in the malignant tertian form. Important references from the literature of malaria are cited in support of this observation.
THE EFFECT OF INTERNAL PROCESSES AND PALEOCLIMATES
Authors: Egyed L.
Published: December 2006

The climatic features of the past periods of geohistory are recorded by some characteristic geological formations such as those of coal, salt, bauxite, the distribution of coral reefs, and glaciations.

The changes in the climate of a given area were first explained by the changing of the climate of insolation of that area due to changes in latitude brought about by polar wandering. On the other hand, part of the climatic changes were related to local influences. However, the periodical intensity variations of the formations indicative for a given set of climatic conditions suggest that the climatic changes can be connected also with the processes of tectonism. On the basis of my studies concerning the earth's interior, I propose to review some of the factors that acted upon the climate of the entire earth in dependence on the processes of tectonism and magmatism.
MEALYBUG WILT OF PINEAPPLE; A REAPPRAISAL*
Authors: Carter Walter
Published: December 2006

A working hypothesis that a latent factor is involved in mealybug wilt was adopted.

The toxic effects of mealybug feeding, apart from mealybug wilt, were demonstrated by the use of mealybugs from host plants not susceptible to wilt and by previously unfed colonies of mealybugs.

These toxic effects, interpreted as inducing conditions of stress, were expressed in growth depression, accentuation of normal color characteristics, and premature fruiting.

Virgin colony feeding can increase the susceptibility of pineapple plants to wilt and can also induce wilt if the test plants are positive sources.

There is sometimes a considerable lag in time between the insect's feeding and the expression of symptoms of the resulting toxicity.

Two examples are recorded of symptoms of genetic weakness being forced into expression by virgin colony feeding or by mealybugs from sisal or grasses.

The wilt‐inducing secretion is believed to be the result of a synthesis by the mealybug, the effectiveness of the mealybugs being governed by the physiological activity of the leaves on which they feed and the number of mealybugs involved.

The capacity to induce wilt is lost if an intermediate feeding as a negative source plant is interposed between the positive source feeding and feeding on the test plant. This is interpreted as an exhaustion process.

The existence of a latent factor has been demonstrated by establishment of positive source value in the absence of wilting. The influence of virgin colony feeding, after inoculation feeding but not before, is clearly shown.

The mature green distal leaf tissue is not receptive to the latent factor although the mealybug can synthesize the wilt secretion on such tissue. There is evidence that Phenacoccus solani (Ferris) can, in some circumstances, transmit the latent factor although it has not thus far induced wilt.

The hypothesis that the insect's secretions activate the latent factor is rejected; instead, the insect's normal secretions as typified by those from the previously unfed insects, increase the concentration and/or distribution of the latent factor in the plant. The insect's secretion causing wilt is believed to be synthesized by the mealybug when it feeds on a plant which has been modified as a nutrional substratum for the mealybug by the presence of the latent factor.

Since the latent factor is transmissible and retained in a vegetatively reproduced plant it is presumed to be a latent virus. Its retention at demonstrable levels is aided by the feeding of fairly large mealybug colonies. The rarity of such colonies in commercial fields accounts therefore for the relative rarity of positive source plants and the almost complete absence of mealybug wilt.
DISC ELECTROPHORESIS ON POLYACRYLAMIDE GELS OF SERUM MUCOIDS OF INDIVIDUALS WITH SELECTED CHRONIC DISEASES*
Authors: Price Winston H. , Harrison Harvey , Ferebee Shirley H.
Published: December 2006

Summary

A reproducible method is described for fractionating the seromucoid component of human serum by disc electrophoresis with polyacrylamide gels. Preliminary results suggest there may be at least five distinct patterns of the seromucoid fractions in testing sera from healthy individuals and patients with a variety of diseases. The significance of differences in patterns remains to be determined.
EFFECTS OF ACIDOSIS ON RESPIRATORY FUNCTION*
Authors: Enson Yale
Published: December 2006

Summary and Conclusions

The net effect of acidosis on the respiratory apparatus is an elevation of ventilation‐perfusion ratios. Alveolar ventilation is augmented; perfusion of the well‐ventilated portion of the lung is enhanced, while perfusion of the poorly ventilated space is diminished. A larger volume of oxygen is made available for release to the tissues.

Carbon dioxide has been shown to have no effect on the pulmonary vasculature or on the oxyhemoglobin dissociation curve independent of the changes in hydrogen ion concentration it produces. Its role with respect to the control of ventilation has not yet clearly been defined.
EFFECTS OF SODIUM LACTATE ON OXYGEN TOXICITY IN THE RAT*
Authors: Felig Philip , Lee William L.
Published: December 2006

Sodium lactate increases survival when administered daily to rats exposed to 98 per cent oxygen. It is suggested that the mechanism of lactate protection may be related to alterations in the redox state of pyridine nucleotides.
THE PLANETARY FOOD POTENTIAL
Authors: Schmitt Walter R.
Published: December 2006

“A knowledge of what nature produces when she is left to herself is one of the indispensable requisites of wise exploitation.”

“Whether the earth was created for mansor with man, they are inter‐dependent correlated expressions of life, and it is either man's God‐given or man's inevitable responsibility to explore, develop and distribute the earth's material natural resources for the benefit rather than the ultimate impoverishment o f himself and his fellow‐men.”
Physiological mechanisms dissociating pulmonary CO2 and O2 exchange dynamics during exercise in humans
Authors: Whipp Brian J.
Published: December 2006

During moderate exercise (below the lactate threshold, θL), muscle CO2 production (
) kinetics are monoexponential, with a time constant (τ) similar to that of O2 consumption. Following a delay incorporating the muscle–lung vascular transit time,
is expressed at the lungs (
) with an appreciably longer τ, reflecting the influence of intervening high‐capacitance CO2 stores. Above θL,
kinetics become complex, resulting from the conflation of the differing rates of HCO3− breakdown and degrees of compensatory hyperventilation with that of the underlying aerobic component. During incremental exercise, the increased rate of
relative to pulmonary O2 uptake (
) can be used to quantify θL validly if aerobic and hyperventilatory sources can be ruled out, i.e. θL is then attributable to the decrease in muscle and blood [HCO3−]. In many cases, however, very rapid incrementation of work rate and/or prior depletion of CO2 stores (by volitional or anticipatory hyperventilation) can yield a ‘false positive’ non‐invasive estimation of θL (‘pseudo‐threshold’) resulting from a slowing of the rate of wash‐in of transient CO2 stores.
Eccentric cardiac hypertrophy was induced by long‐term intermittent hypoxia in rats
Authors: Chen Li‐Mien , Kuo Wei‐Wen , Yang Jaw‐Ji , Wang Shyi‐Gang P. , Yeh Yu‐Lan , Tsai Fuu‐Jen , Ho Ying‐Jui , Chang Mu‐Hsin , Huang Chih‐Yang , Lee Shin‐Da
Published: December 2006

It is unclear whether cardiac hypertrophy and hypertrophy‐related pathways will be induced by long‐term intermittent hypoxia. Thirty‐six Sprague–Dawley rats were randomly assigned into three groups: normoxia, and long‐term intermittent hypoxia (12% O2, 8 h per day) for 4 weeks (4WLTIH) or for 8 weeks (8WLTIH). Myocardial morphology, trophic factors and signalling pathways in the three groups were determined by heart weight index, histological analysis, Western blotting and reverse transcriptase‐polymerase chain reaction from the excised left ventricle. The ratio of whole heart weight to body weight, the ratio of left ventricular weight to body weight, the gross vertical cross‐section of the heart and myocardial morphological changes were increased in the 4WLTIH group and were further augmented in the 8WLTIH group. In the 4WLTIH group, tumour necrosis factor‐α(TNFα), insulin‐like growth factor (IGF)‐II, phosphorylated p38 mitogen‐activated protein kinase (P38), signal transducers and activators of transcription (STAT)‐1 and STAT‐3 were significantly increased in the cardiac tissues. However, in the 8WLTIH group, in addition to the above factors, interleukin‐6, mitogen‐activated protein kinase (MEK)5 and extracellular signal‐regulated kinase (ERK)5 were significantly increased compared with the normoxia group. We conclude that cardiac hypertrophy associated with TNFα and IGF‐II was induced by intermittent hypoxia. The longer duration of intermittent hypoxia further activated the eccentric hypertrophy‐related pathway, as well as the interleukin 6‐related MEK5–ERK5 and STAT‐3 pathways, which could result in the development of cardiac dilatation and pathology.
In Situ Biosurfactant Production by
Bacillus
Strains Injected into a Limestone Petroleum Reservoir
Authors: Youssef N. , Simpson D. R. , Duncan K. E. , McInerney M. J. , Folmsbee M. , Fincher T. , Knapp R. M.
Published: December 2006

Biosurfactant-mediated oil recovery may be an economic approach for recovery of significant amounts of oil entrapped in reservoirs, but evidence that biosurfactants can be produced in situ at concentrations needed to mobilize oil is lacking. We tested whether two
Bacillus
strains that produce lipopeptide biosurfactants can metabolize and produce their biosurfactants in an oil reservoir. Five wells that produce from the same Viola limestone formation were used. Two wells received an inoculum (a mixture of
Bacillus
strain RS-1 and
Bacillus subtilis
subsp.
spizizenii
NRRL B-23049) and nutrients (glucose, sodium nitrate, and trace metals), two wells received just nutrients, and one well received only formation water. Results showed in situ metabolism and biosurfactant production. The average concentration of lipopeptide biosurfactant in the produced fluids of the inoculated wells was about 90 mg/liter. This concentration is approximately nine times the minimum concentration required to mobilize entrapped oil from sandstone cores. Carbon dioxide, acetate, lactate, ethanol, and 2,3-butanediol were detected in the produced fluids of the inoculated wells. Only CO
2
and ethanol were detected in the produced fluids of the nutrient-only-treated wells. Microbiological and molecular data showed that the microorganisms injected into the formation were retrieved in the produced fluids of the inoculated wells. We provide essential data for modeling microbial oil recovery processes in situ, including growth rates (0.06 ± 0.01 h
−1
), carbon balances (107% ± 34%), biosurfactant production rates (0.02 ± 0.001 h
−1
), and biosurfactant yields (0.015 ± 0.001 mol biosurfactant/mol glucose). The data demonstrate the technical feasibility of microbial processes for oil recovery.
The C-Terminal Domain of MinC Inhibits Assembly of the Z Ring in
Escherichia coli
Authors: Shiomi Daisuke , Margolin William
Published: December 2006

In
Escherichia coli
, the Min system, consisting of three proteins, MinC, MinD, and MinE, negatively regulates FtsZ assembly at the cell poles, helping to ensure that the Z ring will assemble only at midcell. Of the three Min proteins, MinC is sufficient to inhibit Z-ring assembly. By binding to MinD, which is mostly localized at the membrane near the cell poles, MinC is sequestered away from the cell midpoint, increasing the probability of Z-ring assembly there. Previously, it has been shown that the two halves of MinC have two distinct functions. The N-terminal half is sufficient for inhibition of FtsZ assembly, whereas the C-terminal half of the protein is required for binding to MinD as well as to a component of the division septum. In this study, we discovered that overproduction of the C-terminal half of MinC (MinC
122-231
) could also inhibit cell division and that this inhibition was at the level of Z-ring disassembly and dependent on MinD. We also found that fusing green fluorescent protein to either the N-terminal end of MinC
122-231
, the C terminus of full-length MinC, or the C terminus of MinC
122-231
perturbed MinC function, which may explain why cell division inhibition by MinC
122-231
was not detected previously. These results suggest that the C-terminal half of MinC has an additional function in the regulation of Z-ring assembly.