bluuebunny/crossref_metadata_2025 huggingface dataset:
Hypothermia, Metabolic Stress, and NMDA‐Mediated Excitotoxicity
Authors: Zeevalk Gail D. , Nicklas William J.
Published: December 2006

Abstract: Isolated embryonic retinas were metabolically stressed by inhibition of glycolysis either with iodoacetate (IOA) or by glucose withdrawal plus 10 mM 2‐deoxy‐D‐glucose, and the effects of hypothermia were examined. Incubation at 30 versus 37°C during 30 min of hypoglycemia with IOA completely reduced the rapid swelling‐related GABA release [6 ± 2 vs. 68 ± 10 nmol/100 mg of protein (mean ± SEM) for 30 and 37°C, respectively]. Histology of the retina immediately following 30 min of metabolic stress at 30°C appeared normal, whereas that at 37°C showed a pattern of acute edema, characteristic of NMDA‐mediated acute excitotoxicity. Coincubation with a competitive or noncompetitive NMDA antagonist, respectively, CGS‐19755 (10 μM) or MK‐801 (1 μM), during 30 min of hypoglycemia at 37°C completely prevented tissue swelling, whereas extracellular GABA content remained at basal levels, indicating that the cytotoxic effects of IOA treatment for 30 min at 37°C were NMDA receptor mediated. Longer periods of hypoglycemia at 37° C produced acute toxicity that was only partially NMDA receptor mediated. Hypothermia delayed the onset of NMDA‐mediated toxicity by 30–60 min. At 30°C, the rate of loss of ATP was slowed during the first several minutes of hypoglycemia (82 and 58% of maximal tissue levels at 30 and 37° C, respectively, at 5 min), but by 10 min, ATP levels were comparably reduced. After a transient exposure of retina to 50 μM NMDA in Mg2+‐free medium, hypothermia significantly attenuated acute GABA release by 30%. At 24 h of recovery, lactate dehydrogenase release was decreased by 37%. Hypothermia had no effect when the exposure was done in medium containing physiological concentrations of Mg2+. The above results suggest that the protective effect of hypothermia during the metabolic insult is predominately directed at the cellular events that lead up to NMDA receptor involvement. Reduction in the rate of loss of ATP, however, does not fully account for the delay in involvement of NMDA receptors during metabolic stress at 30°C. The attenuation of direct NMDA‐mediated toxicity in Mg2+‐free medium further suggests that decreased temperature may result in altered channel properties during situations when the Mg2+ block is lifted.
Effect of N,N′‐Dicyclohexylcarbodiimide on Compartmentation and Release of Newly Synthesized and Preformed Acetylcholine in Torpedo Synaptosomes
Authors: Doležal V. , Sbia M. , Diebler M. F. , Varoqui H. , Morel N.
Published: December 2006

Abstract: Using isolated cholinergic synaptosomes prepared from Torpedo electric organ, we studied the effects of N,N′‐dicyclohexylcarbodiimide (DCCD) on acetylcholine (ACh) synthesis, compartmentation, and release after stimulation. Whereas ACh synthesis was unchanged, ACh compartmentation inside synaptosomes was affected by the presence of DCCD. In resting conditions, the uptake into the synaptic vesicle pool of newly synthesized ACh (i.e., [14C]ACh synthesized in the presence of the drug) was progressively and markedly inhibited as the duration of DCCD preincubation was increased, whereas compartmentation of endogenous ACh was unchanged in the presence of DCCD. After stimulation, the release of endogenous ACh from DCCD‐treated synaptosomes was similar to that of control, in contrast to the release of [14C]ACh, which was markedly inhibited. This inhibition was observed whatever the conditions of stimulation used (gramicidin D, calcium ionophore A23187, or KCI depolarization). The study of the compartmentation of [14C]ACh during stimulation revealed a transfer of highly labeled ACh from the free to the bound ACh compartment in the presence of DCCD, suggesting the existence of several ACh subcompartments within the free and bound ACh pools. The present results are discussed in comparison with the previously reported effects of vesamicol (AH5183) on ACh compartmentation and release.
Glycoprotein III (Clusterin, Sulfated Glycoprotein 2) in Endocrine, Nervous, and Other Tissues: Immunochemical Characterization, Subcellular Localization, and Regulation of Biosynthesis
Authors: Laslop A. , Steiner H.‐J. , Egger C. , Wolkersdorfer M. , Kapelari S. , Hogue‐Angeletti R. , Erickson J. D. , Fischer‐Colbrie R. , Winkler H.
Published: December 2006

Abstract: Specific antisera were raised against the A and B chains of glycoprotein III. lmmunoblotting revealed that in adrenal medulla both chains migrate very closely together in two‐dimensional electrophoresis. Both chains with slightly differing molecular sizes are found in several endocrine tissues and in brain, kidney, liver, and serum. The mRNA has an analogous widespread distribution. In primary cultures of chromaffin cells the level of message becomes significantly increased by treatment with hista‐mine or 12‐O‐tetradecanoylphorbol 13‐acetate/forskoIin. However, the increase is small when compared with that of secretogranin II. The subcellular localization of glycoprotein III in endocrine organs and in the posterior pituitary was investigated by subcellular fractionation and immuno‐electron microscopy. Glycoprotein III was found to be confined to the large densecore vesicles of these organs. For a discussion of the function of glycoprotein III, its localization in these organelles has to be taken into account.
Ionic Composition of Cisternal CSF in Acute Respiratory Acidosis: Lack of Effect of Large Dose Bumetanide
Authors: Javaheri S. , Davis C. , Rogers D. H.
Published: December 2006

Abstract: Sodium/chloride cotransport carrier is known to be involved in transepithelial fluid absorption and secretion in various tissues. Recent studies indicate that Na,K,2CI cotransport carrier also exists in the choroid plexus cells and inhibition of the carrier alters ionic composition of the choroidal tissue. In this study, we report the effects of large dose intravenous bumetanide, a potent inhibitor of Na,K,2CI carrier, on cisternal CSF ionic composition in acute respiratory acidosis in pentobarbital‐anesthetized mechanically ventilated dogs. Renal pedicles were ligated to prevent bumetanide‐induced diuresis. The experirnental group (Group II, n = 7) received 50 mg/kg of bumetanide intravenously and Group I (the control group, n = 7) received the vehicle. Analysis of serum and choroidal plexus tissue revealed bumetanide concentration of ∼10−‐5 mol/L in Group II. During 5 h of acute respiratory acidosis in both groups, the mean Paco2 increased ∼25 mm Hg, with comparable changes in CSF Pco2. In both groups, CSF [HCO3−] and [H+] increased ∼3 mEq/L and 20 nEq/L, respectively. Furthermore, changes in CSF [Na+], [K+], [Ca2+], [Mg2+], [CI−], and [Na+‐CI−] were also similar and were not significantly different from each other. These data show that bumetanide, at the dose that inhibits NaCl cotransport carrier, does not significantly affect ionic composition of cisternal CSF.
The Diversity of Calcium/Calmodulin‐Dependent Protein Kinase II Isoforms in Drosophila Is Generated by Alternative Splicing of a Single Gene
Authors: Griffith Leslie C. , Greenspan Ralph J.
Published: December 2006

Abstract: To investigate the mechanism by which Drosophila generates multiple calcium/calmodulindependent protein kinase II (CaM kinase) subunits, CaM kinase cDNAs were isolated and sequenced. Eight different cDNA sequences, varying only at the junction of the regulatory and association domains of the kinase. were obtained. These results indicate that the diversity of CaM kinase in Drosophila is greater than previously appreciated and is generated by alternative splicing of a single gene. In situ hybridization showed CaM kinase mRNA is present in both neuronal and mneuronal tissues in adult Drosophila. No differential tissue distribution of isoforms was observed.
Alterations in Nitric Oxide‐Stimulated Endogenous ADP‐Ribosylation Associated with Long‐Term Potentiation in Rat Hippocampus
Authors: Duman Ronald S. , Terwilliger Rose Z. , Nestler Eric J.
Published: December 2006

Abstract: The present study examines the possible involvement of nitric oxide (NO)‐stimulated endogenous ADP‐ribosylation in long‐term potentiation (LTP). LTP was induced in hippocampal slices by stimulation of Schaffer collateral inputs to the CA1 pyramidal neurons. Basal and sodium nitroprusside (SNP), which generates NO, stimulation of endogenous ADP‐ribosylation was then studied in CA1 subfields isolated from the slices. Control slices received no treatment or were tetanized in the presence of aminophosphonovaleric acid, an NMDA receptor antagonist that blocks the development of LTP. SNP‐stimulated ADP‐ribosylation of endogenous proteins was reduced by 40–70% in LTP slices relative to control slices. LTP was also associated with a small but significant reduction in basal ADP‐ribosylation activity. The results demonstrate that the induction of LTP is associated with regulation of endogenous ADP‐ribosylation and suggest a role for this type of covalent modification in some aspect of LTP.
Reactivation of NADH Dehydrogenase (Complex I) Inhibited by 1‐Methyl‐4‐(4′‐Alkylphenyl)pyridinium Analogues: A Clue to the Nature of the Inhibition Site
Authors: Krueger Matthew J. , Sablin Sergey O. , Ramsay Rona , Singer Thomas P.
Published: December 2006

Abstract: Expression of the neurotoxicity of 1‐methyl‐4‐phenyl‐1.2,3,6‐tetrahydropyridine, following oxidation to l‐methyl‐4‐phenylpyridinium ion (MPP+), is believed to involve inhibition of mitochondrial electron transport from NADH dehydrogenase (complex l) to ubquinone. MPP+ and its analogues have been shown to Mock electron transport at or near the same site as two powerful inhibitors of mitochondrial respiration, rotenone and piericidin A. All three types of inhibitors combine at two sites on NADH dehydrogenase, a hydrophilic and hydrophobic one, and occupancy of both sites is required for complete inhibition. Tetraphenylboron anion (TPB−) in catalytic amounts is known to increase the effectiveness of positively charged MPP+ analogues in blodclng mitochondrial respiration. A part of this effect involves facitation of the entry of MPP+ oongeners into the hydrophobic site by ion pairing, as has been demonstrated in studies with submitochondrial particles (electron transport particles). This communication documents the fact that TPB−, when present in molar excess over the MPP+ analogues, reverses the inhibition. This seems to involve again strong ion pairing. removal of the inhibitory analogue from one to the two binding sites, and concentration of the inhibitor in the membrane, so that only the hydrophobic binding site remains occupied, resulting in lowering of the inhibiti to 30–40%.
Expression Patterns of Rat Somatostatin Receptor Genes in Pre‐ and Postnatal Brain and Pituitary
Authors: Wulfsen Irk , Meyerhof Wolfgang , Fehr Susanne , Richter Dietmar
Published: December 2006

Abstract:The relative abundances of mRNAs encoding four different somatostatin receptors were examined using PCR techniques during postnatal development of the rat brain and hypophysis. In most tissues, somatostatin receptor 1 and 4 mRNAs are more abundant than those encoding somatostatin receptor 2 and 3. Transcript levels of somatostatin receptor subtype 4 are relatively high in the cortex, hippocampus. and striatum, those of subtype 1 in the cortex and brainstem, and those of subtype 3 in the cerebellum. In situ hybridization revealed the presence of significant amounts of somatostatin receptor 1 mRNA. as early as prenatal day 14, in the trigeminal ganglion and in the neuroepithelial layers surrounding the lateral, third, and fourth ventricles. In the developing cortex a morphological change in the sites of somatostatin receptor 1 gene expression occurs; mRNA is present superficially in the cortex at prenatal stages, appears in all layers shortly after birth, and in adult rats is restricted to the deep cortical layers. In the cerebellum, somatostatin receptor 1 mRNA levels are highest around birth, declining thereafter. In contrast, cerebellar somatostatin receptor 3 transcripts are absent at birth, become detectable around postnatal day 7, and reach a maximal level during maturation.
Uptake of 1‐Methyl‐4‐Phenylpyridinium and Dopamine in the Mouse Brain Cell Nuclei
Authors: Buu Nguyen T.
Published: December 2006

Abstract: The neurotoxin N‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) causes, via its metabolite 1‐methyl‐4‐phenylpyridinium (MPP+), parkinsonism in humans, monkeys, and mice but not in rats. When incubated with mouse brain homogenates, [3H]‐MPP+ is recovered in relatively large concentrations in the brain cell nucleus. Although isolated cell nuclei from rat and mouse brain contain uptake systems for dopamine (DA), only brain cell nuclei from mice avidly take up [3H]MPP+. This nuclear uptake is ATP dependent and can be blocked by ouabain and Nethylmaleimide. It is not, however, affected by neuronal and vesicular blockers such as benztropine. mazindol, and reserpine. Selective uptake of MPP+ into brain cell nuclei may provide a new avenue for future investigation into the complex modes of action of the neurotoxin MPTP.
β‐Amyloid Neurotoxicity in Human Cortical Culture Is Not Mediated by Excitotoxins
Authors: Busciglio Jorge , Yeh John , Yankner Bruce A.
Published: December 2006

Abstract: β‐Amyloid is a metabolic product of the amyloid precursor protein, which accumulates abnormally in senile plaques in the brains of patients with Alzheimer's disease. The neurotoxicity of 0‐amyloid has been observed in cell culture and in vivo, but the mechanism of this effect is unclear. In this report, we describe the direct neurotoxicity of β‐amyloid in high‐density primary cultures of human fetal cortex. In 36‐day‐old cortical cultures, β‐amyloid neurotoxicity was not inhibited by the broad‐spectrum excitatory amino acid receptor antagonist kynurenate or the NMDA receptor antagonist D‐2‐amino‐5‐phosphonovaleric acid under conditions that inhibited glutamate and NMDA neurotoxicity. In 8‐day‐old cortical cultures, neurons were resistant to glutamate and NMDA toxicity but were still susceptible to β‐amyloid neurotoxicity, which was unaffected by excitatory amino acid receptor antagonists. Treatment with β‐amyloid caused chronic neurodegenera‐tive changes, including neuronal clumping and dystrophic neurites, whereas glutamate treatment caused rapid neuronal swelling and neurite fragmentation. These results suggest that β‐amyloid is directly neurotoxic to primary human cortical neurons by a mechanism that does not involve excitatory amino acid receptors.
Glutamate Activates Phospholipase D in Hippocampal Slices of Newborn and Adult Rats
Authors: Holler Thomas , Cappel Eva , Klein Jochen , Löffelholz Konrad
Published: December 2006

Abstract: Phospholipase D (PLD) is activated by many neuro‐transmitters in a novel signal transduction pathway. In the present work, PLD activity was studied comparatively in hippocampal slices of newborn and adult rats. Basal PLD activity in adult rats was almost three times higher than in newborn rats. In newborn rats, L‐glutamate and 1S,3R‐1‐aminocyclopentane‐1,3‐dicarboxylic acid (1S,3R‐ACPD) time‐ and concentrationdependently enhanced the formation of [3H]phosphatidylpropanol ([3H]PP) and of [3H]phosphatidic acid in the presence of 2% propanol. N‐MethylD‐aspartate and kainate (both 1 mM) caused small, but significant increases (∼50%). whereas α‐amino‐3‐hydroxy‐5‐methylisoxazole‐4‐propionate (100 μM) was ineffective. Maximally effective concentrations of glutamate (1 mM) and of 1S,3R‐ACPD (300 μM) increased the PLD activity to almost 300% of basal activity; the EC50 values were 199 and 47 μM, respectively. Glutamate receptor antagonists, such as DL‐2‐amino‐3‐phosphonopropionic acid (AP3). DL‐2‐aminc‐5‐phosphonovalenic acid, and kynurenate (all 1 mM) did not inhibit the glutamate‐evoked increase of PP formation. In slices of adult rats, the response to 1S,3R‐ACPD was significant, but small, whereas glutamate was effective only in the presence of the glutamate uptake inhibitor L‐aspartate‐β‐hydroxarnate. It is concluded that glutamate activates PLD in rat hippocampus through an AP3‐resistant metabotropic receptor. This effect is subject to ontogenetic development, with one important factor being glutamate uptake.
Effect of the Non‐NMDA Receptor Antagonist, 2,3‐Dihydro‐6‐Nitro‐7‐Sulfamoylbenzo(f)quinoxaline, on Local Cerebral Glucose Uptake in the Limbic Forebrain
Authors: Suzdak P. D. , Sheardown M. J.
Published: December 2006

Abstract: The present investigation examined the effect of in vivo antagonism of the α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA) receptor by 2,3‐dihydro‐6‐nitro‐7‐sulfamoylbenzo(f)quinoxaline (NBQX) on local cerebral glucose utilization (LCGU) using the quantitative autoradiographic Pdeoxy[14C]‐glucose method in conscious rats. NBQX, at doses of 10, 30, and 60 mg/kg i.p. or three injections of 30 mg/kg i.p., did not increase LCGU in limbic areas such as the primary olfactory cortex. olfactory tubercle, hippocampus, dentate gyrus, posterior cingulate cortex, mamillary body, caudate nucleus, anterior thalamic nucleus, and nucleus accumbens. NBQX, at doses of 260 mg/kg i.p., decreased LCGU in these brain areas. These data demonstrate that in vivo antagonism of the AMPA receptors by NBQX produces a pattern of alterations in metabolic activity, different from that produced by noncompetitive antagonists of the N‐methyl‐D‐aSpartate (NMDA) receptor, e.g., phencyclidine and MK‐801. Combined with a lack of “phencyclidine‐like” behavior produced by NBQX. these data suggest that antagonism of the AMPA receptor represents a novel mechanism to block excitatory amino acids in the CNS, which may be devoid of unwanted behavioral side effects associated with noncompetitive antagonism of the NMDA receptor.
Scalping of Flavors in Packaged Foods
Authors: Sajilata M.G. , Savitha K. , Singhal R.S. , Kanetkar V.R.
Published: December 2006

ABSTRACT:  Food packaging, although an integral part of the food chain, has a major drawback in that, often, the packaging material interacts with the flavor constituents of the food, causing either a selective or an extensive loss of desirable food flavors or absorption of undesirable off‐flavors from the packaging material, thereby resulting in an eventual loss of quality of the packaged food item. The process is called “scalping” and is of great concern to the food industry, which is always looking out for new avenues in “packaging solutions” for its final product quality needs. The review highlights the various attributes of the scalping process, explores approaches to the reduction of the manifested undesirable effects, and covers other relevant aspects.
Plant odours with potential for a push–pull strategy to control the onion thrips, Thrips tabaci
Authors: Van Tol Rob W. H. M. , James Dale E. , De Kogel Willem Jan , Teulon David A. J.
Published: December 2006

We compared the efficacy of four plant essential oils to repel onion thrips, Thrips tabaci (Lindeman) (Thysanoptera: Thripidae), in the presence of an attractive odour, ethyl iso‐nicotinate in a pasture field. Four horizontal white sticky plates were placed adjacent to (directions: N, S, E, W) a central horizontal white plate (C). After 24 h, in the treatment combination where the four plates were sprayed with essential oil surrounding a central sticky plate sprayed with ethyl iso‐nicotinate, fewer onion thrips were found on the plates treated with sweet marjoram [Origanum majorana L. (Labiatae)] or clove basil [Ocimum gratissimum L. (Labiatae)] (87 and 71% less, respectively) compared to the control treatment of four water‐sprayed plates surrounding a central plate with ethyl iso‐nicotinate. We also compared the distribution of onion thrips on the plates. Relative thrips numbers on each plate were compared with similar (N, S, E, W, and C) plates in the control treatment. There were relatively lower thrips numbers on the south (23% reduction) and west (26% reduction) O. majorana‐treated plates and higher numbers (37% increase) on the central attractant‐treated plate indicating a short‐distance push–pull effect. When four plates were sprayed with the thrips attractant surrounding a central sticky plate sprayed with an essential oil or water (control), only O. majorana reduced the number of thrips on the attractant‐sprayed plates (62% reduction). The distribution of thrips on the different plates within this treatment combination did not change substantially when compared to the distribution in the water‐control treatment. Other essential oils tested (wormwood [Artemisia arborescens L. (Compositae)]) and tea tree [Melaleuca alternifolia (Maiden. & Betche.) Cheel. (Myrtaceae)]) were not effective in any of the treatments. It appears that O. majorana is a promising thrips repellent which could be used for further testing in a push–pull system with the attractant ethyl iso‐nicotinate. The field setup used also proved to be a valuable tool for evaluating the potential of repellents to control onion thrips.
The effect of Bt maize on Sesamia calamistis in South Africa
Authors: Van den Berg J. , Van Wyk A.
Published: December 2006

Bt maize, Zea mays L. (Poaceae) expressing Cry 1Ab insecticidal proteins was introduced for control of Busseola fusca (Fuller) (Lepidoptera: Noctuidae) and Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) in South Africa after its development for control of crambid borers in North America. In the light of the reportedly lower toxicity of Bt maize to certain Noctuidae borers, the effect of Bt maize was evaluated on Sesamia calamistis (Hampson) (Lepidoptera: Noctuidae). The characteristic larval behaviour of S. calamistis may result in reduced exposure to Bt toxin and subsequent high levels of survival. Larvae do not feed on plant whorls like other borer species but penetrate stems directly from behind leaf sheaths where eggs are laid. Greenhouse and laboratory bioassays were done with three Bt maize hybrids and their iso‐hybrids. ‘Whole plant methods’ were used and potted plants artificially infested with eggs or larvae and survival recorded over time. Larval survival was also determined on different plant parts (whorls, stems, tillers, and ears) over time. Bt maize was shown to be highly toxic to S. calamistis. No larvae survived longer than 12–18 days on Bt maize plants in any of the experiments. Adults did not differentiate between Bt and non‐Bt plants in oviposition choice experiments. Sesamia calamistis is polyphagous and occurs in mixed populations with other borer species with which it shares many parasitoid species in Africa. The ecological impact of local extinction of S. calamistis caused by this highly effective transgenic event is therefore not expected to be great.
Detection of fungal metabolites of various Trichoderma species by the aphid Schizaphis graminum
Authors: Ganassi Sonia , De Cristofaro Antonio , Grazioso Pasqualina , Altomare Claudio , Logrieco Antonio , Sabatini Maria Agnese
Published: December 2006

The feeding preferences of alate and apterous morphs of the aphid Schizaphis graminum (Rondani) (Homoptera: Aphididae) were evaluated using leaves treated with powdered rice cultures of four fungal isolates belonging to different species of the genus Trichoderma (Deuteromycotina: Hyphomycetes). All of the fungal isolates restrained alate morphs of S. graminum from visiting treated leaves, but only Trichoderma citrinoviride Bisset also influenced the preference of apterous morphs. Trials carried out with supernatants obtained by centrifuging aqueous suspensions of the fungal cultures showed that the feeding preference of aphids was maintained in the absence of fungal spores and mycelia, supporting the hypothesis that at least part of the fungal metabolites responsible for this effect were water‐soluble compounds. Electrophysiological studies showed that the structures involved in the perception of the fungal metabolites are located on the aphid tarsomeres.
Frequency of alleles conferring resistance to Bacillus thuringiensis maize in Louisiana populations of the southwestern corn borer
Authors: Huang Fangneng , Leonard B.Rogers , Cook Donald R. , Lee Donna R. , Andow David A. , Baldwin Jack L. , Tindall Kelly V. , Wu Xiaoyi
Published: December 2006

Transgenic maize [Zea mays L. (Poaceae)] expressing Bacillus thuringiensis proteins (Bt maize) has become the most important tool for managing stalk borers in maize in the USA. The current strategy for delaying the evolution of resistance in target insects for Bt maize is referred to as high dose/refuge strategy. A key requirement of the strategy is that initial resistance allele frequencies in field insect populations are low (e.g., <0.001). More than 200 iso‐line families of the southwestern corn borer, Diatraea grandiosella Dyar (Lepidoptera: Crambidae), a major target stalk borer pest of Bt maize, were developed from Louisiana populations and evaluated for Bt resistance using a modified F2 screening method during 2005. No major resistance alleles were detected in these populations. The results showed that the expected Bt resistance allele frequency in the Louisiana populations was <0.0035 with 95% probability and a detection power of 83.9 ± 0.6%. The F2 screen indicates that Bt resistance allele frequencies in D. grandiosella are low among the Louisiana populations and should meet the rare resistance allele requirement of the ‘high dose/refuge’ strategy.
Components of resistance to banana weevil (Cosmopolites sordidus) in Musa germplasm in Uganda
Authors: Kiggundu Andrew , Gold Clifford S. , Labuschagne Maryke T. , Vuylsteke Dirk , Louw Schalk
Published: December 2006

A field screening trial undertaken in Uganda showed that a number of Musa L. (Musaceae) cultivars and hybrids displayed high levels of resistance to banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), while most highland banana cultivars tended to be susceptible to weevil attack. In this study, research was undertaken to determine modalities of resistance to banana weevil. Laboratory studies suggested that all cultivars were attractive to the weevil and that females freely oviposited on all cultivars. While some differences were found between cultivars in attractivity and egg numbers, these were not related to subsequent damage. Therefore, antixenosis does not appear to play an important role in host‐plant resistance to banana weevil. Larval survivorship rates in living corms were, for the most part, low on resistant cultivars, suggesting that antibiosis mechanisms offer the primary avenues of resistance. In the laboratory, development was slower on some resistant cultivars although survivorship rates on excised corm material were not as well related to levels of resistance as that on living material. Sap appeared to play a minor role in reducing egg eclosion rates on some resistant cultivars. Methanol extracts from Kayinja, a resistant cultivar, inhibited larval development on corms of susceptible cultivars in the laboratory.
The Influence of Surface Films on the Friction, Adhesion, and Surface Damage of Solids
Authors: Bowden F. P.
Published: December 2006

“All things and everything whatsoever however thin it be which is interposed in the middle between objects that rub together lighten the difficulty of this friction.” (Leonardo da Vinci, 1452–1519).
Measurement of the Incremental Friction Coefficient of Several Homologous Series of Straight‐Chain Hydrocarbon Compounds
Authors: Murray S. F. , Burwell J. T.
Published: December 2006

The incremental friction coefficient fΔ was measured as a function of speed for a number of straight‐chain polar hydrocarbon compounds. These compounds included alcohols, acids, amines, and two esters. In most cases, it was found to be independent of speed at slow speeds and decreased with speed at higher speeds. The amines were the only exception, in that the value of fΔ rose slightly with speed.

The constant slow speed value of fΔ was found to decrease generally with increasing chain length in any single homologous series. There seems to be more correlation of the shape of this curve offΔ vs. chain length with the surface metal than with the lubricant type.

The friction of mixtures of two acids of rather different chain lengths showed no evidence of any strongly preferential adsorption of either component. This agrees with the relatively small difference in their adsorption energies.

The friction of a dibasic acid was high and the damage to the surfaces was great. This agrees with what is known about the orientation of adsorbed molecules of compounds of this type.
The Metal Cutting Process as a Means of Studying the Properties of Extreme Pressure Lubricants
Authors: Shaw Milton C.
Published: December 2006

The cutting of metals by a single point tool involves two main problems of interest to physicists and engineers, namely, the plastic deformation and failure of metals and the friction and wear of sliding surfaces. The material in front of a cutting tool is removed by a process of shear, and fundamental studies of the strength of materials in the fields of solid state physics, engineering plasticity, and physical metallurgy are pertinent to this phase of the cutting process. The material that is detached from the workpiece moves in sliding contact up the face of the cutting tool. The surface of the sliding metal chip is subjected to very high stress, for the entire cutting force is transmitted from the tool to the work material across this surface. The basic principles established by workers in the fields of friction, wear, and lubrication are directly applicable to this second phase of the cutting process. In the present paper, the interrelationship between the shearing and sliding phases of cutting is considered, but only the sliding and frictional aspects of the process are discussed in detail.

The cutting process offers a convenient means for studying the frictional properties of metals in sliding contact. By measuring the horizontal and vertical components of force on the tool and the ratio of the length of chip to length of cut, the coefficient of friction between the tool and the chip may be determined. A simple two component force dynamometer is described which enables the coefficient of friction to be determined. Friction data obtained from this dynamometer for specimens of commercially pure aluminum sliding across a hard steel surface in the presence of carefully purified short chain length saturated and unsaturated chlorinated hydrocarbons are presented and discussed. The chemical reactivity of several of the aluminum‐fluid combinations is presented as determined by noting the time required for a chemical reaction to set in when aluminum is kept in contact with the fluid at an elevated temperature. General agreement is seen to exist between the relative reactivity of a fluid toward aluminum and its frictional performance when used in the cutting of aluminum. It is found that cutting fluids in the gaseous state may be equally as effective as those applied in the liquid state. These observations tend to substantiate the view that fluids are effective lubricants in the extreme region of boundary lubrication, embracing metal cutting by virtue of their ability to react chemically with the chip metal to form a low shear strength solid lubricant. Other frictional data for aluminum cut in conjunction with representative members of a number of homologous series are presented and discussed.

The paper is concluded by a brief discussion of the inherent advantages of the two dimensional cutting process as a means for studying the frictional characteristics of sliding metal surfaces.
The Study of the Fundamentals of Lubrication with the Aid of Large Metal Crystals
Authors: Gwathmey Allan T.
Published: December 2006

Experiments have been conducted with the aid of single crystals of copper which show that the chemical properties of the unit crystal and the processes of friction and wear depend on the crystal face exposed at the surface. The chemical reactions studied included oxidation, wetting, and corrosion. Static friction between bare copper crystals from which all oxide had been removed was found to vary by a factor of four, depending on the face exposed at the surface. When a single crystal was corroded by hot oils it was found that some faces became very rough while others remained very smooth, and this relative smoothness of the surface was shown to affect wear through a film of lead very greatly. The chemical attack of the metals by lubricants and the process of wear between metals was affected greatly by the presence of oxygen in the surrounding atmosphere.
THE EFFECT OF MONOLAYERS ON THE RATE OF EVAPORATION OF WATER
Authors: Archer Robert J. , LaMer Victor K.
Published: December 2006

Summary
THE APPLICATION OF MAMMALIAN CELLS IN CONTINUOUS CULTURE FOR ASSAYS IN VIROLOGY
Authors: Syverton Jerome T. , Scherer William F.
Published: December 2006

Summary
Summary
Authors: Tarjan A. C.
Published: December 2006

A review of the species in the genus Paratylenchus is presented with descriptions and figures of P. sarissus, n. sp., and P. minusculus, n. sp. Tylenchus macrophallus de Man, 1880 is withdrawn from the genus and designated incertae sedis, making P. bukowinensis hlicoletzky, 1922, the type species. Hemicycliophora strenzkei Volz, 1951, is termed incertae sedis while Paratylenchus anceps Cobb, 1923 is placed in species inquirendae. Psratylenchus minutus Linford in Linford, Oliveira, and Ishii, 1949, is regarded a synonym of P. elachistus Steiner, 1949, and P. dianthus Taylor and Jenkins, 1956, a synonym of P. curvitatus van der Linde, 1938. The lectotype of P. nanus Cobb, 1923, the neotypes of P. elachistus and P. projectus Jenkins, 1956, and the male of P. projectus are also described.
QUANTITATION OF STARCH GEL ELECTROPHORESIS*
Authors: Pert James H. , Pinteric Les
Published: December 2006

Quantitative high‐voltage starch gel electrophoresis has been found to be useful as an analytical tool in the study of purified proteins. Much new information can be obtained about complex solutions, such as human plasma, with this method. One of the objectives has been to develop a procedure for high‐speed scanning of large numbers of samples so that the results could be programmed for a digital computer and statistical evaluations could be made. The difficulties of achieving this objective have been discussed, and a new approach to instrumentation is presented that is designed to minimize these problems.
PREPARATIVE ELECTROPHORESIS OF PROTEINS IN ACRYLAMIDE GELS*
Authors: Maizel Jacob V.
Published: December 2006

(1) A simple apparatus is described for adaption of the “disc” electrophoresis techniques to a preparative procedure that permits analytic and radioactive monitoring of the effluent fractions automatically.

(2) The efficiency of the procedure for separating a model system consisting of ribonuclease, trypsin, and chymotrypsin has been demonstrated. In addition, preliminary results concerning the separation of the unexpected multiple proteins of poliovirus are presented.
DISC ELECTROPHORESIS – II METHOD AND APPLICATION TO HUMAN SERUM PROTEINS*
Authors: Davis Baruch J.
Published: December 2006

Summary

The technique of disc electrophoresis has been presented, including a discussion of the technical variables with special reference to the separation of protein fractions of normal human serum.
STARCH GEL IMMUNOELECTROPHORESIS*
Authors: Poulik M. D.
Published: December 2006

Summary

The present status of the starch gel immunoelectrophoretic techniques was reviewed. The advantages and disadvantages of the variety of techniques were demonstrated. New techniques employing electrophoresis in buffers containing urea and applicable to immunoanalytical studies of structural subunits, polypeptide chains, and large peptides of gamma globulins and other proteins were described and examples given. The importance of the resolving power of the media used for the electrophoretic separation prior to the immunoanalysis was discussed.
A COMPARISON OF AGAR AND ACRYLAMIDE GEL MICROIMMUNOELECTROPHORETIC TECHNIQUES FOR THE SEPARATION OF URINARY COLLOIDS*
Authors: Keutel H. J.
Published: December 2006

The differences in the immunoreaction in both gels are small, especially if one knows their origin. Polyacrylamide has the general advantage of being technically easier to handle and quicker than agar gel. The minor expenditure of working time, the shorter running time, the higher elasticity, especially preferable for solid samples, overcome the disadvantage of the longer time required for the immunoreaction. And it is especially important and useful that with pqlyacrylamide gel you can examine several protein solutions simultaneously on one plate under equivalent conditions. This is very convenient for investigation of optimal antigen‐antibody concentrations and for testing of unknown antisera.
STUDIES ON THE GUINEA PIG SERUM FACTOR THAT DETECTS NATURALLY OCCURRING DELAYED ISO‐HYPERSENSITIVITY*
Authors: Lieberman G. , Edelstein G. , Dannis I. M. , Datta S. P. , Battisto J. R.
Published: December 2006

The heritable serum factor that detects naturally occurring delayed‐type iso‐hypersensitivity in guinea pigs was found to be elutable from starch gels following electrophoresis of whole serum. About one‐third of the factor applied was recovered from an area of several bands, devoid of haptoglobins and transferrins, that lies ahead of the slow alpha globulins and behind the fast alpha globulins. The serum factor containing fraction had about 0.5 per cent of the protein content of whole serum. When electrophoresed on paper strips the starch‐gel‐eluted fraction traveled into the beta globulin zone.
BIOLOGICAL APPLICATIONS OF LACTIC DEHYDROGENASE ISOZYMES: CERTAIN METHODOLOGICAL CONSIDERATIONS*
Authors: Vesell Elliot S. , Brody Irwin A.
Published: December 2006

Summary

Numerous biological applications of multiple molecular forms of an enzyme are currently being employed. These applications frequently depend on comparisons of isozyme patterns observed on the starch gel. Some of the methodological factors that significantly affect the LDH isozyme pattern observed on the starch gel have been studied and include extraction procedures, storage of extracts, activity of material applied to the gel, conditions during electrophoresis, and concentration of reagents in the incubating medium. The results revealed LDH 5 to be more sensitive than the other isozymes to several of these factors. Conditions are described for visualization of a hitherto unobserved “y” band in human tissues.
ELECTROPHORETIC SEPARATION OF MULTIPLE FORMS OF PARTICLE ASSOCIATED ACID PHOSPHATASE
Authors: Allen John M. , Gockerman Jon
Published: December 2006

The acid phosphatases of rat liver mitochondrial‐lysosomal fractions have been examined by quantitative and electrophoretic means. Disruption of mitochondrial‐lysosomal material by freeze‐thawing, sonication, or by blendor treatment released approximately 55.0 to 65.0 per cent of the total acid phosphatase activity of the fraction into the unsedimentable phase. Electrophoretic preparations of this material showed a single acid phosphatase‐active site. Treatment of mitochondrial‐lysosomal fractions with 5.0 per cent Triton X‐100 released 98.0 per cent of the total acid phosphatase activity of the fraction into the unsedimentable phase. Electrophoretic preparations of this material showed two major sites of acid phosphatase activity. One of these was identical to that resolved following physical disruption. The other site was characteristically seen only after treatment with Triton X‐100. This acid phosphatase was also released by treatment with digitonin but to a lesser extent. Quantitative and electrophoretic examination indicated that both components of acid phosphatase were concentrated in the mitochondrial‐lysosomal fraction. Physical separation of the acid phosphatase released by detergent treatment from the acid phosphatase released by physical disruption was achieved. It was concluded that two categories of acid phosphatase may reside in lysosomal particles. These phosphatases differ in the nature of their binding to lysosomal structure as well as in their electrophoretic properties.
DISC ELECTROPHORESIS ANALYSIS OF SIALIDASE FROM INFLUENZA VIRUS*
Authors: Seto J. T. , Hokama Y.
Published: December 2006

Disc electrophoresis per se and in combination with immunodiffusion procedures facilitated the characterization of sialidase. Irrespective of the isolation procedures, sialidase of influenza virus (A2 Japan 305/57) appeared to be electrophoretically heterogeneous. This was indicated by disc electrophoresis and analysis of eluates in the “segmentation experiments” and by the “disc immunodiffusion” techniques. It was further noted that “purified” sialidase in phosphate buffer stored at 0 to 5°C. dissociated and simultaneously lost 90 per cent of its enzyme activity. The procedures described above proved valuable, particularly when analyzing limited quantities of material.
ALVEOLAR HYPOVENTILATION WITH NORMAL LUNGS: THE SYNDROME OF PRIMARY OR CENTRAL ALVEOLAR HYPOVENTILATION *
Authors: Seriff Nathan S.
Published: December 2006

This paper describes the cases of primary or central alveolar hypoventilation syndrome that have been reported, as well as three previously unreported cases seen in our hospital. Although the presenting symptoms of the patients were quite different, physiologically they were quite similar. Significant neurological disease was noted to coexist in a majority of the patients. This fact, plus the physiological observations of essentially normal lung and chest bellows function, and a decreased to absent response to inhaled CO2, suggest that this disorder is the result of a disturbance in the medullary respiratory center. The mortality has been 20 per cent. Interesting neuropathological abnormalities have been noted in the area of the respiratory center and elsewhere, consisting of an increased number of capillaries. Whether this is a primary or secondary change is not clear. A variety of therapies has been used in an attempt to augment alveolar ventilation. These include pharmocological agents, hypnosis, implantation of pacemaker electrodes into the diaphragm and later the phrenic nerve, and the use of simulated breath sounds. The details and results of these modalities of therapy are described.
THE REACTION OF THE HUMAN LUNG TO ENRICHED OXYGEN ATMOSPHERE
Authors: Pratt Philip C.
Published: December 2006

1. By reviewing several consecutive series of autopsies, both in adults and children, it has been shown that a recognizable change in pulmonary morphology is present in most patients who have had oxygen therapy for one or more days immediately prior to death.

2. The lesion includes congestion of capillaries and increased thickness of alveolar septa and is interpreted as resulting from pulmonary capillary proliferation.

3. Reasons are presented for interpreting this morphological change as being the result of a physiological reaction to oxygen rather than a result of irritation or patchy atelectasis, or post‐mortem change.

4. Care must be taken in experimental work, especially with mice, to eliminate the possibility that gross findings might be of the post‐mortem variety.
INDICATIONS FOR TRACHEOSTOMY
Authors: Dammann J. Francis
Published: December 2006

Respiratory insufficiency is a frequent complication of major abdominal and thoracic surgery, although it is difficult to recognize. Its presence can only be established by an analysis of the arterial oxygen and carbon dioxide tensions. After open‐heart surgery, the patient's demands are usually increased significantly. This occurs at a time when pulmonary function is usually impaired and the energy necessary to breathe is significantly increased. Our studies in postoperative patients after open‐heart surgery indicate that the work of breathing in most patients is increased many fold and in some patients may be sufficient to produce acute congestive failure. Therefore, we advocate the use of controlled ventilation leaving an oral endotracheal tube in place, to treat respiratory insufficiency or excessive and compromising work of breathing. Occasionally, such therapy must be instituted prior to definitive surgery in order to rest the patient and give the patient enough reserve to withstand a major surgical procedure. If respiratory insufficiency has not been abolished within 72 hours after surgery, we advocate that a tracheostomy be performed and that respirator treatment be continued until respiratory insufficiency is eliminated and the work of breathing no longer places an intolerable work load on the cardiovascular system.
Distribution and Ecology of Campylobacters in Coastal Plain Streams (Georgia, United States of America)
Authors: Vereen Ethell , Lowrance R. Richard , Cole Dana J. , Lipp Erin K.
Published: December 2006

Campylobacter
is the leading cause of bacterium-associated diarrhea in the United States and most developed countries. While this disease is considered a food-borne disease, many clinical cases cannot be linked to a food source. In rural and agrarian areas environmental transmission may be an important factor contributing to case loads. Here we investigated the waterborne prevalence of campylobacters in a mixed-use rural watershed in the coastal plain of southern Georgia (United States). Six sites representing various degrees of agricultural and human influence were surveyed biweekly to monthly for 1 year for the presence of culturable thermophilic campylobacters and other measures of water quality. Campylobacters were frequently present in agriculture- and sewage-impacted stretches of streams. The mean campylobacter counts and overall prevalence were highest downstream from a wastewater treatment plant that handled both human and poultry slaughterhouse waste (≤595 CFU ml
−1
; 100% positive); the concentrations were significantly higher than those for the four upstream sites (
P
< 0.05). The counts were significantly correlated with the number of fecal coliform bacteria, conductivity, pH, and concentrations of nutrients (NO
3
−
, PO
4
3−
, and NH
3
). Campylobacters were isolated more frequently and larger numbers were present during the summer months, similar to the occurrence of clinical cases of campylobacteriosis in this region. A multivariate model showed that the levels were significantly influenced by increasing precipitation, which also peaked in the summer. The results indicate that loading from both human and domestic animal waste may be high in the watershed studied during the summer months. Mixed-use watersheds supporting agriculture production, human populations, and wildlife may be at risk for contamination by campylobacters and may be an important route for human exposure.
Effectiveness of Disinfectants in Killing
Enterobacter sakazakii
in Suspension, Dried on the Surface of Stainless Steel, and in a Biofilm
Authors: Kim Hoikyung , Ryu Jee-Hoon , Beuchat Larry R.
Published: December 2006

The effectiveness of 13 disinfectants used in hospitals, day-care centers, and food service kitchens in killing
Enterobacter sakazakii
in suspension, dried on the surface of stainless steel, and in biofilm was determined.
E. sakazakii
exhibited various levels of resistance to the disinfectants, depending on the composition of the disinfectants, amount and type of organic matrix surrounding cells, and exposure time. Populations of planktonic cells suspended in water (7.22 to 7.40 log CFU/ml) decreased to undetectable levels (<0.30 log CFU/ml) within 1 to 5 min upon treatment with disinfectants, while numbers of cells in reconstituted infant formula were reduced by only 0.02 to 3.69 log CFU/ml after the treatment for 10 min. The presence of infant formula also enhanced the resistance to the disinfectants of cells dried on the surface of stainless steel. The resistance of cells to disinfectants in 6-day-old and 12-day-old biofilms on the surface of stainless steel was not significantly different. The overall order of efficacy of disinfectants in killing
E. sakazakii
was planktonic cells > cells inoculated and dried on stainless steel > cells in biofilms on stainless steel. Findings show that disinfectants routinely used in hospital, day-care, and food service kitchen settings are ineffective in killing some cells of
E. sakazakii
embedded in organic matrices.