bluuebunny/crossref_metadata_2025 huggingface dataset:
Geomagnetic Disturbance and the Orientation of Nocturnally Migrating Birds
Authors: Moore Frank R.
Published: October 2006

Free-flying passerine migrants respond to natural fluctuations in the earth's magnetic field. The variability in flight directions of nocturnal migrants is significantly correlated with increasing geomagnetic disturbance as measured by both the
K
index and various components of the earth's magnetic field. The results indicate that such disturbances influence the orientation of free-flying migrants, but the evidence is not sufficient to show that geomagnetism is a cue in their orientation system.
Morphine and Enkephalin: Analgesic and Epileptic Properties
Authors: Urca Gideon , Frenk Hanan , Liebeskind John C. , Taylor Anna N.
Published: October 2006

Systemic and intracerebroventricular administration of analgesic doses of morphine resulted in large increments of spontaneous multiple unit activity in the periaqueductal gray matter of the awake rat. Intracerebroventricular injection of methionine enkephalin gave analgesia in only 8 of 19 rats, but in all 8, and in no others, increased periaqueductal multiple unit firing was also seen. These findings support the view that the periaqueductal gray matter is actively involved in endogenous mechanisms of analgesia. A striking observation was that enkephalin caused electrographic and behavioral epileptic phenomena in most animals. This observation together with other recent findings suggests that endogenous enkephalin may play some role in epileptogenesis.
Transport Interaction of Cystine and Dibasic Amino Acids in Renal Brush Border Vesicles
Authors: Segal Stanton , McNamara Pamela D. , Pepe Louise M.
Published: October 2006

The uptake of cystine by vesicles prepared from rat kidney brush borders occurs by two distinct transport systems. The higher affinity system is inhibited by the dibasic amino acids lysine, arginine, and ornithine. The lower affinity system, unaffected by dibasic amino acids, appears to correspond to that observed by studying uptake of cystine by kidney slices.
Angiotensin: Physiological Role in Water-Deprivation—Induced Thirst of Rats
Authors: Malvin Richard L. , Mouw David , Vander Arthur J.
Published: October 2006

Cerebroventricular infusion of P-113, the blocking agent of angiotensin II, into rats for 75 minutes prior to their being allowed to drink, significantly attenuated their water intake when they had been deprived of water for 30 hours. However, a similar infusion had no effect on the food intake in rats fasted for 30 hours. The results indicate a physiological role for angiotensin II in the drinking response of rats deprived of water.
Porphyrin Induction: Equivalent Effects of 5αH and 5βH Steroids in Chick Embryo Liver Cells
Authors: Stephens J. K. , Fischer P. W. F. , Marks G. S.
Published: October 2006

The 5αH (A : B trans) and 5βH (A : B cis) steroids are equipotent in inducing δ-aminolevulinic acid synthetase and porphyrin accumulation in chick embryo liver cells maintained in serum-free culture medium. Thus there is no specific steric requirement for porphyrin-inducing activity in steroids.
Phenylketonuria: A New Method for the Simultaneous Determination of Plasma Phenylalanine and Tyrosine
Authors: Shen Rong-sen , Abell Creed W.
Published: October 2006

This quantitative spectrophotometric method is based on the conversion of phenylalanine and tyrosine by phenylalanine ammonia-lyase to
trans
-cinnamic acid and
trans
-coumaric acid, respectively. Neither deproteinization nor prior incubation of the sample is required, and the entire procedure can be performed in 20 minutes. The method is sensitive to 1-micromolar concentrations of the two compounds, and only 20 microliters of plasma or serum is required to determine both phenylalanine and tyrosine simultaneously. These amino acids were determined between molar ratios (phenylalanine to tyrosine) of 0.1 to 40 in the serum or plasma of healthy individuals and plasma of phenylketonuric patients.
DNA Strand Scission by Benzo[
a
]pyrene Diol Epoxides
Authors: Gamper Howard B. , Tung Agatha S.-C. , Straub Kenneth , Bartholomew James C. , Calvin Melvin
Published: October 2006

Syn
- and
anti
-benzo[
a
]pyrene diol epoxides elicit a concentration-dependent nicking of superhelical Col E1 DNA in an in vitro reaction monitored by agarose gel electrophoresis and electron microscopy. This strand scission represents less than 1 percent of the DNA modification by diol epoxide. Kinetic analysis implicates the formation of unstable phosphotriesters, hydrolysis of which nick the DNA.
Progressive Brain Damage Accelerates Axon Sprouting in the Adult Rat
Authors: Scheff S. , Benardo L. , Cotman C.
Published: October 2006

An entorhinal cortical lesion causes undamaged fibers in the deafferented hippocampus to sprout and form new connections within 4 to 7 days after the lesion was made. When a partial lesion of the entorhinal cortex precedes a second, more complete entorhinal lesion by a few days, the rate of axon sprouting is accelerated so that the response to the second lesion occurs within only 2 days. This priming effect is present within 4 days, lasts for a few weeks, and eventually subsides. This acceleration may explain, in part, the faster recovery and reduced deficits seen in behavioral studies that have followed serial lesion paradigms.
Reye's Syndrome: Patient Serum Alters Mitochondrial Function and Morphology in Vitro
Authors: Aprille June R.
Published: October 2006

A direct relationship between a putative Reye's syndrome "serum factor" and generalized mitochondrial damage has been demonstrated in vitro. The clinical features of Reye's syndrome may be secondary to disrupted mitochondrial structure and a consequent impairment of energy-linked functions involving many organs.
Neuron Duplications and Deletions in Locust Clones and Clutches
Authors: Goodman Corey S.
Published: October 2006

Duplications and deletions of identified neurons can occur with a high degree of genetic control and specificity, as shown by examining the ocellar interneurons of locusts from different breeding populations, clutches from single mated pairs, and isogenic animals from parthenogenetic clones.
Glycogen in Sweet Corn
Authors: Morris Daniel Luzon , Morris Carol Tilden
Published: October 2006

A polysaccharide apparently identical with glycogen has been extracted from sweet corn.
4
S
RNA Is Present in Regenerating Optic Axons of Goldfish
Authors: Ingoglia Nicholas A.
Published: October 2006

Regenerating optic axons of goldfish were loaded with [
3
H]RNA by injecting [
3
H]uridine into the eye and allowing time for the radioactivity to be delivered to the optic tectum. The axons were subsequently removed from the tecta by cutting the optic nerve and allowing the optic axons in the tectum to degenerate. Analysis of tectal [
3
H]RNA by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a selective loss of tritiated 4
S
RNA and not ribosomal RNA from the denervated tecta. These results support the hypothesis that regenerating optic axons of goldfish grow back into the tectum carrying 4
S
but not ribosomal RNA.
Erythrocyte Lipids in Heterozygous Carriers of Duchenne Muscular Dystrophy
Authors: Howland John L. , Iyer Susheela L.
Published: October 2006

Erythrocyte membranes from heterozygous carriers of Duchenne muscular dystrophy exhibit a diminished amount of palmitoleic acid when compared to membranes from normal subjects. A similar, but more variable, diminution is observed in the case of patients with this disorder. The change in fatty acid composition appears related to a low membrane triglyceride content and may provide both a possible technique for carrier detection and a clue regarding pathogenesis.
Benzodiazepine Receptor: Demonstration in the Central Nervous System
Authors: Möhler H. , Okada T.
Published: October 2006

Diazepam, a potent minor tranquilizer, binds with high affinity to a specific benzodiazepine receptor that occurs exclusively in the central nervous system. The receptor is mainly localized in the synaptic membrane fraction. Binding to the receptor is stereospecific. Competition for the receptor by various benzodiazepines closely parallels their pharmacological potency.
Breast-Feeding and Population Growth
Authors: Knodel John
Published: October 2006

Abandonment of breast-feeding in parts of the world where contraception is not in common use may mean both higher birthrates and, especially among the poor, higher infant death rates. In this article estimates of the magnitude of these effects are made.
The H-Ion Concentration and the Origin of the Heart Beat
Authors: Spealman C. R.
Published: October 2006

The rate of the frog or guinea pig heart preparation was not significantly influenced by the H-ion concentration when this was kept within limits which allowed the heart to continue beating. The theory that the H-ion concentration is intimately concerned with the origination of the heart beat is not supported by the results of this investigation.
Vasopressin and Oxytocin Are Depleted from Rat Hypothalamic Nuclei After Oral Hypertonic Saline
Authors: George Jack M.
Published: October 2006

Vasopressin and oxytocin were measured by radioimmunoassay in rat posterior pituitary and microdissected hypothalamic areas after 3 and 10 days of oral 2 percent sodium chloride in place of drinking water. There was a significant decrease in concentration of both hormones in posterior pituitary and in specific areas of the hypothalamus. Supraoptic, paraventricular, and arcuate hypothalamic nuclei and the retrochiasmatic area had decreased concentration of one or both hormones following hypertonic saline, while hormone concentration in the suprachiasmatic nucleus and median eminence was unaffected.
Mevalonate Metabolism: Role of Kidneys
Authors: Edmond J. , Fogelman A. M. , Popják G.
Published: October 2006

More than one-half of the amount of mevalonate that is metabolized by pathways not leading to sterols is accounted for by the action of the kidneys. Conversion of mevalonate in vivo to squalene and sterols in the kidneys is confined almost entirely to the proximal and distal convoluted tubules in the cortex. More sterol than squalene is synthesized from mevalonate not only in the liver but also in the kidney.
Formation of Cyanamides from Secondary Amines in Human Saliva
Authors: Wishnok John S. , Tannenbaum Steven R.
Published: October 2006

1-Morpholinocarbonitrile (1-cyanomorpholine) was formed from morpholine when this amine was incubated in whole human saliva. Several other secondary amines appeared to form analogous products, and this transformation may therefore represent a general metabolic pathway for amines in saliva.
Genetic Predisposition and Stress-Induced Hypertension
Authors: Friedman Richard , Iwai Junichi
Published: October 2006

When chronically exposed to an approach-avoidance conflict, rats with a genetic susceptibility to hypertension showed persistent elevations in systolic blood pressure, but rats with a genetic resistance to hypertension did not. Hence, psychic stress is selectively efficacious in producing hypertensive effects depending on genetic predisposition of the animal.
Dufour's Gland: Source of Sex Pheromone in a Hymenopterous Parasitoid
Authors: Weseloh Ronald M.
Published: October 2006

Females of
Apanteles melanoscelus
and
Apanteles liparidis
produce a sex pheromone in Dufour's gland of their reproductive system. Males of both species exhibit premating behavior when in contact with filter paper smears of the gland of their respective females.
Suid Evolution and Correlation of African Hominid Localities: An Alternative Taxonomy
Authors: Cooke H. B. S.
Published: October 2006

New phylogenies were recently proposed by White and Harris, who recognized 7 genera and 16 species of fossil and extant suids from sub-Saharan Africa. This scheme is regarded here as oversimplified and an alternative is suggested, in which 9 genera and 21 species are recognized. The taxonomic and phylogenetic differences do not have any significant effect on the stratigraphic interpretations offered by White and Harris.
Cooperative Computation of Stereo Disparity
Authors: Marr D. , Poggio T.
Published: October 2006

The extraction of stereo-disparity information from two images depends upon establishing a correspondence between them. In this article we analyze the nature of the correspondence computation and derive a cooperative algorithm that implements it. We show that this algorithm successfully extracts information from random-dot stereograms, and its implications for the psychophysics and neurophysiology of the visual system are briefly discussed.
The Biochemical High-Risk Paradigm: Behavioral and Familial Correlates of Low Platelet Monoamine Oxidase Activity
Authors: Buchsbaum Monte S. , Coursey Robert D. , Murphy Dennis L.
Published: October 2006

A population of individuals potentially at risk for psychiatric disorders was identified by screening 375 college student volunteers for low platelet monoamine oxidase (MAO) activity levels. The lower and upper 10 percent in MAO activity were interviewed and family history data were obtained. Low-MAO probands reported more frequent psychiatric or psychological counseling and problems with the law. Families of low-MAO probands had an eightfold increase in the incidence of suicide or suicide attempts over those of high-MAO probands. This suggests that reduced MAO levels, reported previously in patients with affective disorders and chronic schizophrenia, may predict a vulnerability to psychiatric disorder.
Filaroides hirthi
: Experimental Transmission Among Beagle Dogs Through Ingestion of First-Stage Larvae
Authors: Georgi Jay R.
Published: October 2006

Four beagle dogs were found to be infected with sexually mature
Filaroides hirthi
lungworms from 1 to 3 months after they ingested material containing first-stage larvae of this parasite. Infection by first-stage larvae opens the theoretical possibility of autoinfection of which few nematode parasites are capable.
Cellulosic Microfibrils: Nascent Stages of Synthesis in a Higher Plant Cell
Authors: Weiss Gerson , O'Byrne E. M. , Steinetz B. G.
Published: October 2006

Plasma samples from peripheral and ovarian veins were obtained from women at cesarean section. A peptide that immunologically cross-reacts with a specific antiserum to porcine relaxin is present in all samples. Its concentration is four times higher in the ovarian vein draining the ovary, which contains the corpus luteum of pregnancy, than in either the peripheral vein or the contralateral ovarian vein. Secretion of ovarian relaxin correlates with secretion of ovarian progesterone, thus providing another index of luteal function.
Effect of Charcoal-Broiled Beef on Phenacetin Metabolism in Man
Authors: Pantuck E. J. , Hsiao K.-C. , Conney A. H. , Garland W. A. , Kappas A. , Anderson K. E. , Alvares A. P.
Published: October 2006

When charcoal-broiled beef was fed to human volunteers, who were then given phenacetin orally, the concentration of phenacetin in the plasma was lowered, but its half-life in the plasma was not changed. The data suggest that feeding charcoal-broiled beef enhances the metabolism of orally administered phenacetin in the intestine or during its first pass through the liver, or both.
Time-Dependent Disruption of Morphine Tolerance by Electroconvulsive Shock and Frontal Cortical Stimulation
Authors: Kesner Raymond P. , Priano D. J. , DeWitt J. R.
Published: October 2006

Electroconvulsive shock or frontal cortex stimulation administered to rats at 5 but not at 180 minutes after an initial administration of morphine sulfate disrupted the development of one-trial tolerance to the analgesic effects of morphine sulfate. It is suggested that development of tolerance may be mediated by cellular mechanisms and memory processes similar to those thought to underlie conventional learning.
The Chemical Removal of Salts from Sea Water to Produce Potable Water
Authors: Spealman C. R.
Published: October 2006

A simple chemical method is described for the removal of most of the salts from sea water. The final product, containing 0.58 per cent. dissolved material which is apparently composed of urates and sulfates, is not unpleasant in taste and is not expected to cause toxic effects if used as drinking water.
Extraction of a Highly Potent Penicillin Inactivator from Penicillin Resistant Staphylococci
Authors: Kirby William M. M.
Published: October 2006

A highly potent penicillin inactivator has been extracted from 7 strains of
Staph. aureus
(coagulase positive), all of which were naturally penicillin resistant. No such inhibitor was present in extracts of 7 penicillin sensitive strains of
Staph. aureus.
Processes Controlling Arm Movements in Monkeys
Authors: Polit Andres , Bizzi Emilio
Published: October 2006

The experiments identify some of the processes underlying arm movements in rhesus monkeys. Three monkeys were trained to point to a target with the hand and forearm and to hold that position for about 1 second to obtain a reward. Forearm movements were performed without sight of the arm before and after bilateral dorsal rhizotomy. In both intact and deafferented animals, we unexpectedly displaced the forearm prior to movement initiation and observed that the arm moved accurately to the target. These results are relevant to the question of what is being controlled by motor commands. The controlled variable appears to be an equilibrium point between agonist and antagonist muscles. The findings suggest that the feedback system plays a major role in updating and adjusting the central programs subserving the execution of learned motor patterns.
SHOCK PHYSICS DATA RECONSTRUCTION USING SUPPORT VECTOR REGRESSION
Authors: SAKHANENKO NIKITA A. , LUGER GEORGE F. , MAKARUK HANNA E. , AUBREY JOYSREE B. , HOLTKAMP DAVID B.
Published: October 2006

This paper considers a set of shock physics experiments that investigate how materials respond to the extremes of deformation, pressure, and temperature when exposed to shock waves. Due to the complexity and the cost of these tests, the available experimental data set is often very sparse. A support vector machine (SVM) technique for regression is used for data estimation of velocity measurements from the underlying experiments. Because of good generalization performance, the SVM method successfully interpolates the experimental data. The analysis of the resulting velocity surface provides more information on the physical phenomena of the experiment. Additionally, the estimated data can be used to identify outlier data sets, as well as to increase the understanding of the other data from the experiment.
FRACTAL ANALYSIS OF DIFFERENT EASTERN AND WESTERN MUSICAL INSTRUMENTS
Authors: DAS ATIN , DAS PRITHA
Published: October 2006

In this paper, we attempt musical analysis by measuring fractal dimension (D) of musical pieces played by several musical instruments. We collected solo performances of popular instruments of Western and Eastern origin as samples. We attempted usual spectral analysis of the selected clips to observe peaks of fundamental and harmonics in frequency regime. After appropriate processing, we converted them into time series data sets and computed their fractal dimension. Based on our results, we conclude that instrumental musical sounds may have higher Ds than those computed from vocal performances of different types of Indian songs.
Influence of Electrotonic Structure and Synaptic Mapping on the Receptive Field Properties of a Collision-Detecting Neuron
Authors: Peron Simon P. , Krapp Holger G. , Gabbiani Fabrizio
Published: October 2006

The lobula giant movement detector (LGMD) is a visual interneuron of Orthopteran insects involved in collision avoidance and escape behavior. The LGMD possesses a large dendritic field thought to receive excitatory, retinotopic projections from the entire compound eye. We investigated whether the LGMD's receptive field for local motion stimuli can be explained by its electrotonic structure and the eye's anisotropic sampling of visual space. Five locust ( Schistocerca americana) LGMD neurons were stained and reconstructed. We show that the excitatory dendritic field and eye can be fitted by ellipsoids having similar geometries. A passive compartmental model fit to electrophysiological data was used to demonstrate that the LGMD is not electrotonically compact. We derived a spike rate to membrane potential transform using intracellular recordings under visual stimulation, allowing direct comparison between experimental and simulated receptive field properties. By assuming a retinotopic mapping giving equal weight to each ommatidium and equally spaced synapses, the model reproduced the experimental data along the eye equator, though it failed to reproduce the receptive field along the ventral-dorsal axis. Our results illustrate how interactions between the distribution of synaptic inputs and the electrotonic properties of neurons contribute to shaping their receptive fields.
Modulation of Cellular and Synaptic Variability in the Lamprey Spinal Cord
Authors: Parker David , Bevan Sarah
Published: October 2006

Variability is increasingly recognized as a characteristic feature of cellular, synaptic, and network properties. While studies have traditionally focused on mean values, significant effects can result from changes in variance. This study has examined cellular and synaptic variability in the lamprey spinal cord and its modulation by the neuropeptide substance P. Cellular and synaptic variability differed in different types of cell and synapse. Substance P reduced the variability of subthreshold locomotor-related depolarizations and spiking in motor neurons during network activity. These effects were associated with a reduction in the variability of spiking in glutamatergic excitatory network interneurons and with a reduction in the variance of excitatory interneuron-evoked excitatory postsynaptic potentials (EPSPs). Substance P also reduced the variance of postsynpatic potentials (PSPs) from crossing inhibitory and excitatory interneurons, but it increased the variance of inhibitory postsynpatic potentials (IPSPs) from ipsilateral inhibitory interneurons. The effects on the variance of different PSPs could occur with or without changes in the PSP amplitude. The reduction in the variance of excitatory interneuron-evoked EPSPs was protein kinase A, calcium, and N-methyl-d-aspartate (NMDA) dependent. The NMDA dependence suggested that substance P was acting postsynaptically. This was supported by the reduced variability of postsynaptic responses to glutamate by substance P. However, ultrastructural analyses suggested that there may also be a presynaptic component to the modulation, because substance P reduced the variability of synaptic vesicle diameters in putative glutamatergic terminals. These results suggest that cellular and synaptic variability can be targeted for modulation, making it an additional source of spinal cord plasticity.
Safety of Meloxicam in Aspirin-Hypersensitive Patients with Asthma and/or Nasal Polyps
Authors: Bavbek Sevim , Dursun A. Berna , Dursun Engin , Eryılmaz Adil , Mısırlıgil Zeynep
Published: October 2006

Background: The anti-inflammatory actions of acetylsalicylic acid (ASA)/non-steroidal anti-inflammatory drugs (NSAIDs) are thought to be due to inhibition of COX-2, whereas the side effects such as gastric damage and aspirin-induced asthma are mediated through inhibition of COX-1. Therefore, a new class of drugs with COX-2 selectivity may be well tolerated by patients with ASA/NSAIDs hypersensitivity. Objective: We investigated whether subjects with asthma and/or nasal polyps (NP) and analgesic intolerance proven by oral ASA provocation test tolerated the selective COX-2 inhibitor, meloxicam. Methods: All subjects were first challenged with ASA using a 2-day, single-blind, placebo-controlled oral provocation test. Thereafter, the subjects showing positive response to ASA provocation underwent a single-blind, placebo-controlled challenge with a cumulative dose of 7.5 mg of meloxicam on 2 separate days. One and three fourths of the divided doses of placebo and the active drug were given at 1-hour intervals. Clinical symptoms, lung function, and blood pressure were monitored during these challenge protocols. Results: Twenty-one patients with asthma and/or NP (10 males and 11 females; mean age: 38.4 ± 2.9 years) who reacted to ASA challenges were enrolled in the study. Response to ASA provocation was rhinitis + bronchospasm in 13, and extrabronchial reactions in 8 (isolated rhinitis in 3) patients. Mean PD20 was 163.4 ± 39.9 mg ASA among patients who reacted with bronchospasm to ASA. Only 1 patient reacted to meloxicam challenge at a cumulative dose of 7.5 mg. Conclusion: This study indicates that 7.5 mg of meloxicam is a safe alternative treatment for ASA-hypersensitive asthma and/or NP patients with proven hypersensitivity via oral ASA challenges.
Different Protection Mechanisms after Pretreatment with Glycine or α-Lipoic Acid in a Rat Model of Warm Hepatic Ischemia
Authors: Duenschede Friedrich , Westermann Stefanie , Riegler Nina , Miesner Imke , Erbes Kirsten , Ewald Patrick , Kircher Achim , Schaefer Hella , Schneider Julius , Schad Arno , Dutkowski P. , Kiemer A.K. , Junginger Theodor
Published: October 2006

Background/Aim: α-Lipoic (LA) acid pretreatment has previously been described to reduce ischemia/reperfusion injury (IRI) after warm liver ischemia, whereas glycine pretreatment has been shown to be protective mostly in models of cold hepatic ischemia. The aim of this study was to determine whether glycine decreases IRI after warm hepatic ischemia. Furthermore we investigated whether doses of LA other than those used previously are also protective against IRI after warm hepatic ischemia. Methods: Selective liver ischemia was maintained over a period of 90 min. In long-term as well as short-term experiments we studied IRI in several groups comparing animal survival as the pivotal endpoint. Results: Animal survival was improved by glycine and 5,000 µmol LA, whereas all animals died within 3 days after pretreatment with 50 µmol LA. In the glycine group we observed a tendency towards decreased apoptosis-related cell death measured by the activity of caspase-3 in liver tissue and the percentage of TUNEL-positive hepatocytes in comparison to the untreated group. Serum α-glutathione S-transferase, lipid peroxidation, and caspase-3 activity as well as the percentage of TUNEL-positive hepatocytes and the percentage of liver necrosis were only significantly decreased by 5,000 µmol LA pretreatment. Liver tissue levels of tumor necrosis factor (TNF)α were reduced only in the glycine group whereas TNFα was increased in the untreated as well as the LA group. Levels of TNFα mRNA were upregulated in both the glycine- and LA-pretreated groups. Conclusion: Our data show that increased animal survival by glycine was accompanied by a reduced TNFα content in liver tissue. Protection by glycine is likely to result from a reduction in adverse TNFα effects. Administration of high-dose LA on the other hand led to a significant reduction in necrosis- and apoptosis-related cell death in IRI of the liver without a reduction in liver TNFα.
New patient-oriented summary measure of net total gain in certainty for dichotomous diagnostic tests
Authors: Linn Shai , Grunau Peter D
Published: October 2006

Objectives

To introduce a new, patient-oriented predictive index as a measure of gain in certainty.

Study design

Algebraic equations.

Results

A new measure is suggested based on error rates in a patient population. The new Predictive Summary Index (PSI) reflects the true total gain in certainty obtained by performing a diagnostic test based on knowledge of disease prevalence, i.e., the overall additional certainty. We show that the overall gain in certainty can be expressed in the form of the following expression: PSI = PPV+NPV-1. PSI is a more comprehensive measure than the post-test probability or the Youden Index (J). The reciprocal of J is interpreted as the number of persons with a given disease who need to be examined in order to detect correctly one person with the disease. The reciprocal of PSI is suggested as the number of persons who need to be examined in order to correctly predict a diagnosis of the disease.

Conclusion

PSI provides more information than J and the predictive values, making it more appropriate in a clinical setting.
Epidemiology and clinical outcome of virus-positive respiratory samples in ventilated patients: a prospective cohort study
Authors: Daubin Cédric , Parienti Jean-Jacques , Vincent Sophie , Vabret Astrid , du Cheyron Damien , Ramakers Michel , Freymuth François , Charbonneau Pierre
Published: October 2006

Introduction

Respiratory viruses are a major cause of respiratory tract infections. The prevalence of a virus-positive respiratory sample and its significance in patients requiring mechanical ventilation remain unknown.

Methods

We conducted a cohort study in all consecutive adults ventilated for more than 48 hours admitted to a 22-bed medical intensive care unit during a 12-month period. Respiratory samples at the time of intubation were assessed by culture, by indirect immunofluorescence assay or by molecular methods in systematic tracheobronchial aspirates. Patients with a virus-negative respiratory sample at the time of intubation were considered unexposed and served as the control group.

Results

Forty-five viruses were isolated in 41/187 (22%) patients. Rhinovirus was the most commonly isolated virus (42%), followed byherpes simplex virus type 1 (22%) and virus influenza A (16%). In multivariate analysis controlling for the Acute Pathophysiology and Chronic Health Evaluation II score, patients with respiratory disorder at admission (adjusted odds ratio, 2.1; 95% confidence interval, 0.8–5.1; P = 0.12), with chronic obstructive pulmonary disease/asthma patients (adjusted odds ratio, 3.0; 95% confidence interval, 1.3–6.7; P = 0.01) and with admission between 21 November and 21 March (adjusted odds ratio, 2.8; 95% confidence interval, 1.3–5.9; P = 0.008) were independently associated with a virus-positive sample. Among the 122 patients admitted with respiratory disorder, a tracheobronchial aspirate positive for respiratory viruses at the time of intubation (adjusted hazard ratio, 0.273; 95% confidence interval, 0.096–0.777; P < 0.006) was independently associated with better survival, controlling for the Simplified Acute Physiology Score II and admission for cardiogenic shock or cardiac arrest. Among the remaining 65 patients, a virus-positive sample on intubation did not predict survival.

Conclusion

We confirmed the pathogenic role of respiratory viruses in the intensive care unit, particularly rhinovirus. We suggest, however, that the prognostic value of virus-associated respiratory disorder is better than that of other causes of respiratory disorder.
Suppression of C/EBPα expression in periportal hepatoblasts may stimulate biliary cell differentiation through increasedHnf6andHnf1bexpression
Authors: Yamasaki Harufumi , Sada Aiko , Iwata Takeyuki , Niwa Tohru , Tomizawa Minoru , Xanthopoulos Kleanthis G. , Koike Toru , Shiojiri Nobuyoshi
Published: October 2006

The expression of C/EBPα, which may govern transcription of mature hepatocyte marker genes, was suppressed in periportal hepatoblasts in mouse liver development, leading to biliary cell differentiation. This study was undertaken to analyze how inactivation of the Cebpa gene affects biliary cell differentiation and gene expression of the regulatory genes for that differentiation, including Hnf1b and Hnf6. In the knockout mouse liver at midgestation stages, pseudoglandular structures were abundantly induced in the parenchyma with elevated expression of Hnf6and Hnf1b mRNAs. The wild-type liver parenchyma expressed mRNAs of these transcription factors at low levels, though periportal biliary progenitors had strong expression of them. These results suggest that expression of Hnf6 and Hnf1b is downstream of C/EBPαaction in fetal liver development, and that the suppression of C/EBPαexpression in periportal hepatoblasts may lead to expression of Hnf6and Hnf1b mRNAs. Immunohistochemical studies with biliary cell markers in knockout livers demonstrated that differentiated biliary epithelial cells were confined to around the portal veins. The suppression of C/EBPα expression may result in upregulation of Hnf6 and Hnf1b gene expression, but be insufficient for biliary cell differentiation. When liver fragments of Cebpa-knockout fetuses, in which hepatoblasts were contained as an endodermal component, were transplanted in the testis of Scid (Prkdc) male mice, almost all hepatoblasts gave rise to biliary epithelial cells. Wild-type hepatoblasts constructed mature hepatic tissue accompanied by biliary cell differentiation. These results also demonstrate that the suppression of C/EBPα expression may stimulate biliary cell differentiation.
Hydrogen sulfide as an oxygen sensor/transducer in vertebrate hypoxic vasoconstriction and hypoxic vasodilation
Authors: Olson Kenneth R. , Dombkowski Ryan A. , Russell Michael J. , Doellman Meredith M. , Head Sally K. , Whitfield Nathan L. , Madden Jane A.
Published: October 2006

How vertebrate blood vessels sense acute hypoxia and respond either by constricting (hypoxic vasoconstriction) or dilating (hypoxic vasodilation) has not been resolved. In the present study we compared the mechanical and electrical responses of select blood vessels to hypoxia and H2S,measured vascular H2S production, and evaluated the effects of inhibitors of H2S synthesis and addition of the H2S precursor, cysteine, on hypoxic vasoconstriction and hypoxic vasodilation. We found that: (1) in all vertebrate vessels examined to date, hypoxia and H2S produce temporally and quantitatively identical responses even though the responses vary from constriction (lamprey dorsal aorta; lDA), to dilation (rat aorta; rA), to multi-phasic (rat and bovine pulmonary arteries;rPA and bPA, respectively). (2) The responses of lDA, rA and bPA to hypoxia and H2S appear competitive; in the presence of one stimulus, the response to the other stimulus is substantially or completely eliminated. (3)Hypoxia and H2S produce the same degree of cell depolarization in bPA. (4) H2S is constitutively synthesized by lDA and bPA vascular smooth muscle. (5) Inhibition of H2S synthesis inhibits the hypoxic response of lDA, rA, rPA and bPA. (6) Addition of the H2S precursor, cysteine, doubles hypoxic contraction in lDA, prolongs contraction in bPA and alters the re-oxygenation response of rA. These studies suggest that H2S may serve as an O2 sensor/transducer in the vascular responses to hypoxia. In this model, the concentration of vasoactive H2S in the vessel is governed by the balance between endogenous H2S production and its oxidation by available O2.
Fabrication of Gold Sulfide Nanoparticles Using the Protein Cage of Apoferritin
Authors: Yoshizawa Keiko , Iwahori Kenji , Sugimoto Kenji , Yamashita Ichiro
Published: October 2006

Au2S nanoparticles (NPs) were prepared in the cavity of the cage-shaped protein, apoferritin. Apoferritin has a cavity, 7 nm in diameter, and the diameter of fabricated Au2S NPs is about the same size with the cavity and size dispersion was small. Although Au2S is generally insoluble in water, our prepared Au2S NPs can be dissolved over 100 mg/mL in water due to the water-soluble protein shell. This solubility will make it possible to place and construct nanostructures made of Au2S NPs.
Tracheostomy‐related subglottic stenosis: Bacteriologic pathogenesis
Authors: Sasaki Clarence T. , Horiuchi Masatoshi , Koss Neal
Published: October 2006

Subglottic stenosis carries devastating consequences. Its pathogenesis, and therefore prevention, have thus far eluded precise definition. The following data suggest that tracheostomy results in a contaminated wound, secondarily infecting a larynx which may have been injured by prior intubation, fracture, or surgery. The interpretation of these data is based upon the tested assumption that infection prolongs healing of injured tissue and predisposes to scar and stricture formation. Therefore, the ability to control stomal contamination by the judicious use of topical or systemic antibiotics may play an important role in the prevention of complications in an organ functionally by‐passed by the tracheostomy cannula.
Transoral management of localized carcinoma of the oral cavity using the CO2 laser
Authors: Strong M. Stuart , Vaughan Charles W. , Healy Gerald B. , Shapshay Stanley M. , Jako Geza J.
Published: October 2006

Since 1972 we have been cautiously exploring the use of CO2 laser in the management of carefully selected cases of localized carcinoma of the oral cavity. At the present time our experience is based on the treatment of 57 patients with cancer of the oral cavity.

The CO2 laser has been found to be an indispensable tool in the transoral management of T1 carcinomas, multiple superficial carcinoma, extensive leukoplakia and verrucous carcinoma. The laser allows precise excision of the lesion and involved mucosa and provides an excellent specimen for histologic verification of the margins.

The morbidity of laser excision is minimal, so that a tracheotomy is not needed and patients can almost always be discharged on the following day. (Follow‐up data on those patients at risk for 30 months indicate excellent control rates.)
Partial laryngectomy after radiation failure
Authors: Nichols Richard D. , Stine Patrick H. , Greenawald Kenneth J.
Published: October 2006

Of patients given radiation therapy as primary treatment for limited carcinoma of the larynx, 15‐32% will not be cured by this modality. The recurrent tumor and primary site can be encompassed with a partial laryngectomy in a certain number of these individuals. This report reviews the subject of partial laryngectomy after radiation failure and reports experience with 18 patients who had partial laryngectomies to control recurrent or persistent carcinoma after full dose radiation therapy.

Four patients had biopsy cures. Local tumor control was achieved by partial laryngectomy in 10 of 14 patients. Three of 4 partial failures were salvaged with total laryngectomy. Major wound complications were noted in 4 patients. Prolonged healing was observed in most patients. Prognosis is probably as good with partial laryngectomy as with total laryngectomy.
American burkitt's lymphoma of the mastoid
Authors: Welling D. Bradely , McCabe Brian F.
Published: October 2006

Primary clinical presentation of malignant lymphoma in the middle ear is rare. One case of African Burkitt's lymphoma involving the mastoid has been reported, but the case herein presented would appear to be the first case of American Burkitt's lymphoma in the literature. American and African varieties have distinct clinical presentations but are histologically identical. Chemotherapy is effective against these aggressive tumors.

A 6‐year‐old boy with the first known case of American Burkitt's lymphoma of the mastoid is presented. He is doing well 23 months from the onset of symptoms.
Treatment of obstructive sleep apnea by uvulopalatopharyngoplasty
Authors: Dickson R. I. , Blokmanis A.
Published: October 2006

Although uvulopalatopharyngoplasty has been proposed as a treatment for obstructive sleep apnea, there is limited objective data concerning its efficacy. We have examined 40 patients with moderate to severe obstructive sleep apnea before and 3 months following uvulopalatopharyngoplasty. A standardized questionnaire and detailed overnight sleep study were performed before and after surgery. In addition, 15 patients were retested 1 year postoperatively.

Uvulopalatopharyngoplasty resulted in a statistically significant reduction in symptoms, blood pressure, apnea index, and total apneic time. There was no significant change in patient weight or sleep gas exchange.

Seventy‐seven percent had a reduction in apnea index of greater than 50%, which is better than other reported series using a more conservative approach. Our more aggressive surgical method will be shown in detail.

The 1‐year follow‐up studies revealed the results were maintained or slightly improved over time.
Corrosive esophageal injuries I. A study of nine cases of concurrent accidental caustic ingestion
Authors: Thompson James N.
Published: October 2006

Treatment of corrosive injuries of the esophagus remains largely unsatisfactory, and severe esophageal burns still frequently result in stricture with accompanying morbidity or death. The nine patients presented here with 3‐year follow‐up accidentally drank a concentrated alkaline solution. All were teenagers or young adults who drank from the same bottle while at a party. The problems encountered in these patients led us to conclude that all patients with moderate to severe corrosive injury of the esophagus should have assessment of the entire esophagus and stomach at the time of initial assessment. Six patients underwent diagnostic laparotomy and one underwent thoracotomy as well for assessment of his esophageal injuries. Had we followed the traditional approach of esophagoscopy only to the level of the first circumferential burn, more severe and potentially life‐threatening injuries would have been missed. Early endoscopic evaluation of the esophagus and stomach remains the standard for diagnosis; however, complete assessment may require laparotomy or thoracotomy. Early resection of necrotic tissue in the esophagus or stomach can lead to increased survival.
Autologous fibrin tissue adhesive biodegration and systemic effects
Authors: Harris David M. , Siedentop Karl H. , Ham Kevin R. , Sanchez Ben
Published: October 2006

A series of experiments was conducted to investigate the rate of Autologous Fibrin Tissue Adhesive (AFTA) degradation by the fibrinolysis inhibitor, epsilon amino caproic acid (EACA). The duration of AFTA clots in vitro, subcutaneous, and in the middle ear was prolonged for a time interval that was proportional to the concentration of EACA in Component II of the adhesive. No toxic reactions were observed in the middle or inner ear. Systemic pathology (thrombosis or emboli) could not be related to the presence of EACA applied in the middle ear or directly into the blood stream at concentrations (mg/kg body weight) up to 1,500 times that expected to occur during surgery on humans.
The effect of glutathione and vitamins A, C, and E on acute skin flap survival
Authors: Hayden Richard E. , Paniello Randal C. , Yeung Cecil S. T. , Bello Steven L. , Dawson Steven M.
Published: October 2006

Vitamins A, C, and E act as antioxidants and as free radical scavengers in biological systems. Glutathione is involved in several reactions in vitamin metabolism and also plays an important role in cell membrane protection against lipid peroxidation by free radicals. We sought to use these natural defense mechanisms against oxygen free radicals formed during reperfusion of ischemic skin flaps. An acute axial random skin flap model was utilized in the rat. Vitamins or glutathione were administered by oral gastric tube or intravenously in the perioperative period, and survival of the flap was measured at 1 week. Glutathione, beta‐carotene, ascorbic acid and alpha‐D‐tocopherol showed mean flap survival of 84% to 89%, each of which was significantly improved over saline controls (67% p <.0005). The mechanisms and biochemistry of these vitamins, and their interactions with other vitamins and with glutathione, are discussed, along with clinical implications of free radical scavenging and skin flap survival.
Corrosive esophageal injuries. II. An investigation of treatment methods and histochemical analysis of esophageal strictures in a new animal model
Authors: Thompson James N.
Published: October 2006

The unique clinical experience of having to treat simultaneously nine young adults who had ingested the same corrosive substance prompted this investigation in rabbits of the pathophysiology of corrosive esophageal injury and of drugs that might prevent formation of stricture. Treatment of experimental corrosive esophageal injury in these animals consisted of antegrade dilatation and administration of two lathyrogenic drugs, colchicine and penicillamine, in various combinations. This study demonstrated that the rabbit can serve as a suitable animal model for study of corrosive injury of the esophagus, that penicillamine given alone affected wound healing with less severe stricture after such an injury, and that colchicine was associated with delayed wound healing and severe stricture.
Some observations concerning 200 stapedectomies: Fifteen years postoperatively
Authors: Bo Massimo Del , Zaghis Arturo , Ambrosetti Umberto
Published: October 2006

In this study, a statistical evaluation of the hearing improvement, the incidence of postoperative tinnitus and vertigo, and the permanency of the surgically restored hearing of 120 women and 80 men operated on for otosclerosis between 1970 and 1971 was undertaken.

The standardized operating procedure in all of these cases involved the use of a Gelfoam® and wire prosthesis (Schuknecht 3). All patients underwent normal audiological examinations, including determination of bone and air conduction values. Pure tone thresholds were determined by averaging the values for 500, 1,000, 2,000, and 4,000 Hz. The incidence (10%) of severe sensorineural loss in regard to age, preoperative bone conduction, and oval window pathology was examined.

Severe sensorineural losses had occurred immediately postoperatively in 14 of the ears. In the remaining ears, losses were gradual in the course of 15 years. Hearing thresholds in ears not subjected to operation were also determined.
Chirality Amplification of Porphyrin Assemblies Exclusively Constructed from Achiral Porphyrin Derivatives
Authors: Chen Penglei , Ma Xiaoguang , Duan Pengfei , Liu Minghua
Published: October 2006

Two achiral porphyrin derivatives, 5,10,15,20‐tetrakis(4‐methoxyphenyl)‐21H,23H‐porphine (TPPOMe) and 5,10,15,20‐tetrakis(4‐hydroxyphenyl)‐21H,23H‐porphine (TPPOH), were spread onto an air/water interface. The spreading films were transferred onto solid substrates by the Langmuir–Schaefer (LS) method. Although both of the porphyrin derivatives are achiral species, the transferred LS multilayer films shows macroscopic supramolecular chirality, which is suggested to be due to the spontaneous symmetry breaking that occurs at the air/water interface. A strong CD signal is observed from the as‐deposited TPPOH LS film, while a relatively weak CD signal is detected from that of TPPOMe. Interestingly, when the TPPOMe LS film was annealed in high vacuum, a significant amplification of the supramolecular chirality is observed. Atomic force microscopy observations confirm that TPPOMe form more ordered aggregates upon annealing. It is suggested that the small amount of chiral assemblies formed in the as‐deposited LS film grow into larger ones following the “sergeants and soldiers” principle during the annealing process.
Hydroxyapatite Nanocrystals Modified with Acidic Amino Acids
Authors: Boanini Elisa , Fini Milena , Gazzano Massimo , Bigi Adriana
Published: October 2006

HA‐aspartic acid (HA‐ASP) and HA‐glutamic acid (HA‐GLU) composite nanocrystals were synthesized in aqueous medium. The relative amino acid content, determined through HPLC analysis, increases with the amino acid concentration in solution up to a maximum of about 7.8 wt.‐% for HA‐ASP and 4.3 wt.‐% for HA‐GLU composites. The dimensions of the composite nanocrystals decrease on increasing the amino acid content. The line profile analysis of the X‐ray diffraction reflections was performed using: (i) the Scherrer method, (ii) the Warren–Averbach approach, and (iii) the Rietveld refinement. The results indicate that the broadening of the diffraction peaks is partly due to the decrease of crystallite size on increasing amino acid content, and even more to the simultaneous increase of microstrain. The different extent of structural disorder induced by the two amino acids, in agreement with their different incorporation, suggests a greater affinity of aspartic acid for hydroxyapatite structure. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Changing perceptions and outcomes: The accountability paradox in Tennessee
Authors: Noland Brian E.
Published: October 2006

A long‐standing accountability system in Tennessee is now subject to change.