bluuebunny/crossref_metadata_2025 huggingface dataset:
Form of the Pubic Bone in Neanderthal Man
Authors: Stewart T. D.
Published: October 2006

Shanidar I and III from Iraq have the same peculiar form of pubis as Tabūn I from Palestine. These are the only such pubes known to exist. These facts suggest that Neanderthal man (Shanidar-Tabūn) and an early variety of modern man (Skhūl) coexisted during Mousterian times in this part of the world.
Is Reserpine Tranquilization Linked to Change in Brain Serotonin or Brain Norepinephrine?
Authors: Sulser F. , Brodie Bernard B.
Published: October 2006

Reserpine, when administered to animals stressed by exposure to cold, does not induce sedation or appreciably lower brain serotonin, but markedly lowers brain norepinephrine. Reserpine in cold-exposed hypophysectomized rats elicits sedation and releases both amines equally. The results support the view that the tranquilizing action of reserpine is not related to brain norepinephrine loss but rather to change in the level of brain serotonin.
Immunoglobulin A-Induced Shift of Epstein-Barr Virus Tissue Tropism
Authors: Sixbey John W. , Yao Qing-Yun
Published: October 2006

Increased immunoglobulin A (IgA) antibodies to the Epstein-Barr virus (EBV) appear months to years before the clinical onset of nasopharyngeal carcinoma and define populations at high risk for this EBV-associated epithelial cancer common in south China. In the human HT-29 epithelial cell line, polymeric IgA (pIgA) specific for EBV promoted infection of the otherwise refractory epithelial cells. When bound to pIgA, EBV entered epithelial cells through secretory component-mediated IgA transport but no longer infected B lymphocytes. Such an immune-induced shift in EBV tissue tropism provides a paradigm for endogenous spread of EBV in the immune host that predicts infectious sequelae of epithelium.
Regulatory Elements that Control the Lineage-Specific Expression of
myoD
Authors: Goldhamer David J. , Faerman Alexander , Shani Moshe , Emerson Charles P.
Published: October 2006

The molecular basis of skeletal muscle lineage determination was investigated by analyzing DNA control elements that regulate the myogenic determination gene
myo
D. A distal enhancer was identified that positively regulates expression of the human
myo
D gene. The
myo
D enhancer and promoter were active in myogenic and several nonmyogenic cell lines. In transgenic mouse embryos, however, the
myo
D enhancer and promoter together directed expression of a
lacZ
transgene specifically to the skeletal muscle lineage. These data suggest that during development
myo
D is regulated by mechanisms that restrict accessibility of
myo
D control elements to positive trans-acting factors.
Enhanced Degradation of the Ferritin Repressor Protein During Induction of Ferritin Messenger RNA Translation
Authors: Goessling Lisa Smith , Daniels-McQueen Susan , Bhattacharyya-Pakrasi Maitrayee , Lin Jih-Jing , Thach Robert E.
Published: October 2006

Induction of ferritin synthesis in cultured cells by heme or iron is accompanied by degradation of the ferritin repressor protein (FRP). Intermediates in the degradative pathway apparently include FRP covalently linked in larger aggregates. The effect of iron on FRP degradation is enhanced by porphyrin precursors but is decreased by inhibitors of porphyrin synthesis, which implies that heme is an active agent. These results suggest that translational induction in this system may be caused by enhanced repressor degradation. While unique among translational regulatory systems, this process is common to a variety of other biosynthetic control mechanisms.
Avoidance Conditioning and Alcohol Consumption in Rhesus Monkeys
Authors: Clark Robert , Polish Edwin
Published: October 2006

Measures of intake of water and of a solution of 20-percent alcohol in water were determined in rhesus monkeys before, during, and after avoidance training. Alcohol consumption increased during, and decreased after, avoidance sessions. Water intake remained the same or decreased during avoidance sessions and stayed at this level after the sessions.
Isolation of an Unidentified Agent from the Respiratory Tract of Chickens
Authors: Bankowski R. A. , Corstvet R. E. , Clark G. T.
Published: October 2006

A relatively stable filterable virus, not previously described, which hemagglutinated red blood cells of chickens, was isolated from the tracheae of birds suffering from an unusually severe outbreak of infectious laryngotracheitis. The latter disease concealed the infection caused by the new hemagglutinating agent, which was shown to cause, by itself, a mild and transient illness in susceptible chickens. Preliminary studies indicate that the new agent may be a new entity of the myxovirus group.
Interhemispheric Effects of Cortical Lesions on Brain Biochemistry
Authors: Krech David , Rosenzweig Mark R. , Bennett Edward L.
Published: October 2006

Unilateral lesions in the visual and somesthetic cortex of rat brain cause a slight but significant increase in the cortical cholinesterase activity in the contralateral hemisphere. There is some indication of strain differences in this effect. No change in cholinesterase activity is found in the subcortical brain. These findings may be helpful in understanding mechanisms of interdependence among brain areas.
Simultaneous Study of Behavior and Brain Waves
Authors: Gianascol Alfred J. , Yeager Charles L.
Published: October 2006

A technique for the simultaneous audiovisual recording of behavior and brain waves is described. The absence of muscle movement artifact, despite unlimited activity of the patient, suggests that telemetering may be adaptable for routine electroencephalography.
Molybdenum as a Factor Limiting Primary Productivity in Castle Lake, California
Authors: Goldman Charles R.
Published: October 2006

A trace-element deficiency is evident from carbon-14 bioassays of Castle Lake's natural phytoplankton populations. Increase in photosynthetic rates with the addition of molybdic acid or sodium molybdate has been demonstrated throughout the year. It is likely that other trace elements may also be found to be limiting factors in lakes having a limited watershed.
Glass Insulated Platinum Microelectrode
Authors: Wolbarsht M. L. , MacNichol E. F. , Wagner H. G.
Published: October 2006

Microelectrodes for electrophysiological use have been prepared easily and quickly by electrolytically sharpening platinum iridium alloy wire and coating with molten glass. The desirable combination of the electrical characteristics and strength of the platinum iridium wire with the exceptional durability of glass insulation has long been known, but earlier methods of fabrication were difficult and tedious.
Perturbations of the Orbit of the Echo Balloon
Authors: Shapiro Irwin I. , Jones Harrison M.
Published: October 2006

The motion of the Project Echo communications satellite during its first 12 days clearly confirms previous predictions of the influence of solar radiation pressure. During this time, solar pressure reduced perigee height by 44 km. The approximate value of 1.1 × 10
-18
g/cm
3
has been obtained for the average air density at the 1600-km altitude of the satellite.
Interpeduncular Nucleus and Avoidance Conditioning in the Rat
Authors: Thompson Robert
Published: October 2006

Rats trained to make a jumping response to the onset of a visual stimulus lost the habit after damage to the interpeduncular nucleus of the midbrain. It was noted, however, that the majority of the operated animals showed perfect retention of the "fear" response to the conditioned stimulus.
Simultaneous Generalization Gradients for Appetitive and Aversive Behavior
Authors: Hearst Eliot
Published: October 2006

In the presence of a bright light five monkeys were trained to press a lever to avoid shock and to pull a chain for food reward. When tested with a series of lights dimmer than the conditioning stimulus, the monkeys showed a sharp gradient of effect for the rewarded response, in contrast to a very flat gradient for the avoidance response.
Block of Ca
2+
Wave and Ca
2+
Oscillation by Antibody to the Inositol 1,4,5-Trisphosphate Receptor in Fertilized Hamster Eggs
Authors: Miyazaki Shun-ichi , Yuzaki Michisuke , Nakada Ken , Shirakawa Hideki , Nakanishi Setsuko , Nakade Shinji , Mikoshiba Katsuhiko
Published: October 2006

The concentration of cytoplasmic free calcium (Ca
2+
) increases in various stimulated cells in a wave (Ca
2+
wave) and in periodic transients (Ca
2+
oscillations). These phenomena are explained by inositol 1,4,5-trisphosphate (IP
3
)-induced Ca
2+
release (IICR) and Ca
2+
-induced Ca
2+
release (CICR) from separate intracellular stores, but decisive evidence is lacking. A monoclonal antibody to the IP
3
receptor inhibited both IICR and CICR upon injection of IP
3
and Ca
2+
into hamster eggs, respectively. The antibody completely blocked sperm-induced Ca
2+
waves and Ca
2+
oscillations. The results indicate that Ca
2+
release in fertilized hamster eggs is mediated solely by the IP
3
receptor, and Ca
2+
-sensitized IICR, but not CICR, generates Ca
2+
waves and Ca
2+
oscillations.
Repression of the Insulin-Like Growth Factor II Gene by the Wilms Tumor Suppressor WT1
Authors: Drummond lain A. , Madden Stephen L. , Rohwer-Nutter Patricia , Bell Graeme I. , Sukhatme Vikas P. , Rauscher Frank J.
Published: October 2006

The Wilms tumor suppressor gene
wt1
encodes a zinc finger DNA binding protein, WT1, that functions as a transcriptional repressor. The fetal mitogen insulin-like growth factor II (IGF-II) is overexpressed in Wilms tumors and may have autocrine effects in tumor progression. The major fetal IGF-II promoter was defined in transient transfection assays as a region spanning from nucleotides -295 to +135, relative to the transcription start site. WT1 bound to multiple sites in this region and functioned as a potent repressor of IGF-II transcription in vivo. Maximal repression was dependent on the presence of WT1 binding sites on each side of the transcriptional initiation site. These findings provide a molecular basis for overexpression of IGF-II in Wilms tumors and suggest that WT1 negatively regulates blastemal cell proliferation by limiting the production of a fetal growth factor in the developing vertebrate kidney.
Evaporative Water Loss of Small Vertebrates, as Measured with an Infrared Analyzer
Authors: Chew Robert M. , Dammann Arthur E.
Published: October 2006

Evaporation is linearly and inversely related to absolute humidity at 26° to 27°C. The relative rate of loss in desert reptiles, rodents, and anurans is about 1:10:40. The maximum rate of water loss is about 2.5 and 5 times the basal rate, respectively, in pocket mice and sand lizards. The ratio of loss from lung to loss from skin is about 84:16 in kangaroo rats and 70:30 in rattlesnakes.
Phylogeny of Priapulida
Authors: Shapeero William L.
Published: October 2006

The systematic position of the small invertebrate group, Priapulida, is uncertain. In more recent publications they are classified usually as pseudocoelomates in the division Aschelminthes. A histological investigation of
Priapulus caudatus
, a widely distributed species, reveals the body cavity to be a coelom, its lining a peritoneum. These features, and others, indicate the priapulids to be. coelomates rather than pseudocoelomates. Unique morphology perhaps qualifies the group for the status of phylum.
Coesite from Wabar Crater, near Al Hadida, Arabia
Authors: Chao E. C. T. , Fahey J. J. , Littler Janet
Published: October 2006

The third natural occurrence of coesite, the high pressure polymorph of silica, is found at the Wabar meteorite crater, Arabia. The Wabar crater is about 300 feet in diameter and about 40 feet deep. It is the smallest of three craters where coesite has been found.
Isolation of
Blastomyces dermatitidis
from Soil
Authors: Denton J. Fred , McDonough E. S. , Ajello Libero , Ausherman Robert J.
Published: October 2006

Through the intravenous inoculation of soil suspensions in the tail vein of mice,
Blastomyces dermatitidis
was recovered from a Lexington, Kentucky, soil sample. The positive specimen was collected in a tobacco-stripping barn. The shed had sheltered a dog that died of blastomycosis 2 years before the sample was collected.
Synthesis of Uracil under Conditions of a Thermal Model of Prebiological Chemistry
Authors: Fox Sidney W. , Harada Kaoru
Published: October 2006

Uracil has been formed under thermal conditions which yield other materials of theoretical prebiochemical significance. The chemical evidence for the identity of uracil rests on chromatography, spectrography, color tests, and melting points and analyses of isolated material. The place of uracil in a scheme of biochemical origins, including carbon dioxide as an intermediate, is discussed.
Correlation of Nuclear Volume and DNA Content with Higher Plant Tolerance to Chronic Radiation
Authors: Sparrow Arnold H. , Miksche Jerome P.
Published: October 2006

The causes of extreme differences in radiosensitivities of different plant (or animal) species have long puzzled radiobiologists. Our investigations show that, for diploid species, the larger the nuclear volume, the more radiosensitive the organism. Correspondingly, species with large nuclei have more deoxyribonucleic acid (DNA) per nucleus than those possessing small nuclei. Our data now make it possible to predict fairly accurately the tolerance of plant species to ionizing radiation on the basis of average nuclear volume and DNA content. The same correlations are expected to hold for some microorganisms and for animals and may explain differences in sensitivities of different cell types in many living organisms.
Hemorrhage in a Coccinellid Beetle and Its Repellent Effect on Ants
Authors: Happ George M. , Eisner Thomas
Published: October 2006

Special refinements of the bleeding mechanism of the Mexican bean beetle,
Epilachna varivestis
Mulsant, are described, and the defensive effectiveness of the mechanism against ants is demonstrated. Ants may have provided a major selective force in the evolution of the mechanism.
Blood Flow Measured by Doppler Frequency Shift of Back-Scattered Ultrasound
Authors: Franklin Dean L. , Schlegel William , Rushmer Robert F.
Published: October 2006

The Doppler shift of ultrasound, scattered from moving elements within a stream of blood, is related to the velocity of blood flow. A flowmeter based on this principle has been constructed and was used to record blood flow through intact vessels in dogs.
Biosynthesis of Stigmasterol in Tomato Fruits
Authors: Bennett Raymond D. , Heftmann Erich , Purcell Albert E. , Bonner James
Published: October 2006

The presence of stigmasterol in tomato fruits was demonstrated. Labeled mevalonic acid was incorporated into this sterol, while sodium acetate was not. The identity of the isolated product was established by rigorous purification to constant specific activity, melting point determinations, and infrared spectrum
Calendar of Gametogenic Development in the Prepuberal Male Mouse
Authors: Nebel Bernard R. , Amarose Anthony P. , Hackett Elizabeth M.
Published: October 2006

The timing of the first meiotic cycle in the young male mouse was established by serial sacrifices and subsequent paraffin sectioning of testis and epididymis. Meiosis commences in mice 8 to 10 days old. The highest frequency of any one phase of meiosis was found at days 17 to 19, when 47 percent of the tubules were found to contain late pachytene.
Bow Wave Riding of Dolphins
Authors: Yuen Heeny S. H.
Published: October 2006

Dolphins riding bow waves were observed through underwater viewing ports. The postures assumed by the dolphins show that they present their bodies rather than the ventral surfaces of their flukes to the propellant forces of the bow wave.
Measurement of the Relations between Chromosomes and Behavior
Authors: Erlenmeyer-Kimling L. , Hirsch Jerry
Published: October 2006

The relations between the three major
Drosophila melanogaster
chromosomes and individual differences in geotaxis are assayed in populations selected for positive and negative geotaxis and in an unselected foundation population. The major changes which occur with selection and the differential roles in geotaxis of the three large chromosomes are described.
Potassium-Argon Age of Devils Tower, Wyoming
Authors: Bassett William A.
Published: October 2006

Devils Tower consists of columnar phonolite porphyry which contains large phenocrysts of orthoclase. Potassiumargon determinations on the orthoclase indicate an age of 40.5 million years ± 4 percent. This is consistent with the geologically accepted Tertiary age.
Competition for Overlapping Sites in the Regulatory Region of the
Drosophila
Gene
Krüppel
Authors: Hoch Michael , Gerwin Nicole , Taubert Heike , Jäckle Herbert
Published: October 2006

A 730-base pair element regulates expression of the
Drosophila
gap gene Krüppel (
Kr
) in response to the fly anterior morphogen
bicoid
(
bcd
). Two hormone receptor-like proteins, encoded by the genes
knirps
(
kni
) and
tailless
(
tll
), bind specifically to the element. In vitro,
kni
protein competes with the homeodomain-containing
bcd
protein in binding to a 16-base pair target sequence. In vivo experiments suggest that both
kni
and
tll
act as competitive repressors of
bcd
-mediated activation of
Kr
. These results suggest a mechanism by which developmental genes can be regulated in response to an activating morphogen gradient antagonized by repressors.
Hypothalamic Control of Feeding and Self-Stimulation
Authors: Hoebel Bartley G. , Teitelbaum Philip
Published: October 2006

Hypothalamic sites which control feeding exert a corresponding control over lateral hypothalamic self-stimulation. This was demonstrated in rats bearing four, intrahypothalamic electrode-cannulas for electrical stimulation or chemical injection. Self-stimulation of the lateral hypothalamus was inhibited by ventromedial excitation or by excessive feeding. Both self-stimulation and feeding were accelerated (disinhibited) by ventromedial ablation or anesthetization. Thus food acts via the ventromedial hypothalamus to inhibit not only feeding, but also lateral hypothalamic self-stimulation.
Spontaneous Discharge of Single Neurons during Sleep and Waking
Authors: Evarts Edward V. , Bental Ephraim , Bihari Bernard , Huttenlocher Peter R.
Published: October 2006

Populations of single neurons in visual cortex, middle suprasylvian association cortex, and brain stem of cat show greater variance of spontaneous discharge rates during waking than during sleep; this change in variance occurs in the absence of significant changes in mean discharge rates. Neurons which discharge rapidly during sleep tend to discharge even more rapidly during waking, whereas neurons with relatively low rates of discharge during sleep tend to have reduced spontaneous activity during waking.
Negative Selection of Precursor Thymocytes Before their Differentiation into CD4
+
CD8
+
Cells
Authors: Takahama Yousuke , Shores Elizabeth W. , Singer Alfred
Published: October 2006

Thymic selection of the developing T cell repertoire is thought to occur at the CD4
+
CD8
+
stage of differentiation and to be determined by the specificity of the T cell receptors (TCRs) that CD4
+
CD8
+
thymocytes express. However, TCR signals can inhibit the differentiation of precursor thymocytes into CD4
+
CD8
+
cells, which suggests that selection might occur earlier than thought. Indeed, in a negatively selecting male thymus, CD4
-
CD8
lo
precursor thymocytes that express a transgenic TCR to male antigen are developmentally arrested as a consequence of antigen encounter and fail to become CD4
+
CD8
+
. Thus, negative selection can occur before the CD4
+
CD8
+
stage of differentiation.
Visual Acuity When Eyes Are Pursuing Moving Targets
Authors: Mackworth Norman H. , Kaplan Ira T.
Published: October 2006

Acuity for a stationary test object decreased when the eye followed a moving fixation target. This effect became larger with increased target speed, with decreased illumination, and with longer exposure of the acuity object. The acuity object's orientation also influenced the results.
Acquisition and Extinction of the Classically Conditioned Eyelid Response in the Albino Rabbit
Authors: Schneiderman Neil , Fuentes Israel , Gormezano I.
Published: October 2006

Comparisons of the performance curve of a classical conditioning group with the curves of control groups provided unequivocal evidence that elicitation of eyelid responses to the conditioned stimulus was acquired by associations formed between the conditioned stimulus and the unconditioned stimulus.
Enhancement of Punitive Behavior by Audio-Visual Displays
Authors: Walters Richard H. , Thomas Edward Llewellyn , Acker C. William
Published: October 2006

A group of male hospital attendants watched the knife-fight scene from the motion picture
Rebel Without a Cause
. A second, control, group watched an innocuous educational film. The group who watched the fight (the motion picture with aggressive content), and who were then required to run a conditioning experiment, punished errors more severely, using a significantly higher level of intensity of the punitive electric shock, than did the control group.
Thermal Stability Comparison of Purified Empty and Peptide-Filled Forms of a Class I MHC Molecule
Authors: Fahnestock Margaret L. , Tamir Ilana , Narhi Linda , Bjorkman Pamela J.
Published: October 2006

A secreted form of a class I major histocompatibility complex (MHC) molecule was denatured and renatured in vitro in the absence of peptide. The resulting empty class I heterodimer was immunologically reactive and structurally similar to a heterodimer renatured in the presence of an appropriate restricted peptide. Thermal stability profiles indicated that the two forms of heterodimer differed in their resistance to denaturation by heat but that a significant portion of the empty class I heterodimers had a native conformation at physiological temperatures. Free energies calculated from these data gave a direct measure of the stabilization of the class I MHC molecule that resulted from peptide binding.
NO News Is Good News
Authors: Culotta Elizabeth , Koshland Daniel E.
Published: October 2006

A startlingly simple molecule unites neuroscience, physiology, and immunology, and revises scientists' understanding of how cells communicate and defend themselves.
Chemical Control of Water Loss in Growing Plants
Authors: Stoddard E. M. , Miller P. M.
Published: October 2006

Immersing the roots of growing strawberry plants in aqueous solutions of 8-hydroxyquinoline sulfate closes the stomata, reduces water loss, and increases the time before complete wilting under drought conditions. Under such drought conditions plant survival and vigor are increased. Prolonged closing of the stomata seems to be the principal mode of action of the chemical.
Biological and Oceanographic Observations under an Antarctic Ice Shelf
Authors: Littlepage Jack L. , Pearse John S.
Published: October 2006

Animal life has been shown to exist under the Ross Ice Shelf, from samples obtained with bottom-sampling equipment through naturally occurring cracks in the permanent shelf ice. An abundant fauna, comprising at least nine phyla, was found on a mud and rock bottom. This fauna differs somewhat from that found under nearby seas periodically covered with sea ice 2 to 3 meters thick.
Alveolar Epithelial Cell Mitochondria as Source of the Surface-Active Lung Lining
Authors: Klaus M. , Reiss O. K. , Tooley W. H. , Piel C. , Clements J. A.
Published: October 2006

We propose that the surface-active lining of the mammalian lung is formed in the mitochondria of the alveolar epithelial cells. Findings supporting this hypothesis are the presence of strong surfactant uniquely in the washed mitochondrial fraction of mammalian lung, almost complete loss of mitochondrial lamellar forms accompanying loss of lung surface activity after vagotomy, and the absence of strong surface activity from the lung extracts of animals whose alveolar lining cells show no lamellar forms.
The Quest for Human Cancer Viruses
Authors: Trentin John J. , Yabe Yoshiro , Taylor Grant
Published: October 2006

A new approach to the important but difficult task of revealing possible human tumor viruses has been presented in this article. By systematic testing of already known human viruses for oncogenic properties, it was found that in hamsters injected intrapulmonarily with tissue culture fluid of human type 12 adenovirus within 24 hours after birth there was a very high incidence of malignant tumors at the site of injection in from 1 to 3 months. The tumor-inducing activity was not lost by filtration through Selas 02 filters or by tissue culture passages in HeLa cells. Tumors thus induced grew in, and killed, a high percentage of the unconditioned young adult hamsters into which they were transplanted. No such tumors occurred in hamsters injected with control tissue culture fluid or with culture fluids of the other viruses tested, or in control breeder hamsters. The possibility that contamination with polyoma virus and simian virus 40 might be responsible for the tumors induced was specifically excluded by a variety of tests. The possible involvement of still other, as yet unknown, contaminant viruses was excluded by a positive association of the tumor-inducing ability with the adenovirus content. Of eight human sera tested, only those four which neutralized the adenovirus-type cytopathic effect also neutralized the tumor-inducing effect. Of 700 human sera tested, 26 percent contained CPE-neutralizing antibodies for type 12 adenovirus at titers of 1:4 and higher.
Metabolic Requirements for the Swimming Activity of Three Antarctic Fishes
Authors: Wohlschlag Donald E.
Published: October 2006

The logarithm of the amount of oxygen consumed per unit swimming velocity in meters per minute for steadily swimming antarctic fishes at freezing temperatures is of the same order as the rate for temperate species at their lower temperature ranges. In contrast to temperate fishes, the antarctic fishes have their greatest swimming activity around -1.8°C and a level of no excess activity at about +2°C.
A Single Amino Acid That Determines the Sensitivity of Progesterone Receptors to RU486
Authors: Benhamou Brigitte , Garcia Teresa , Lerouge Thierry , Vergezac Agnes , Gofflo Dominique , Bigogne Claire , Chambon Pierre , Gronemeyer Hinrich
Published: October 2006

The progesterone analog RU486, an abortifacient, inhibits the action of progestins in humans but not in chickens or hamsters. Substitution of cysteine at position 575 by glycine in the hormone binding domain (HBD) of the chicken progesterone receptor (cPR) generated a cPR that binds RU486 and whose activity is antagonized by that compound. In fact, all receptors that bind RU486 have a glycine at the corresponding position. The hamster PR, like cPR, has a cysteine. Only glycine—not methionine or leucine—at position 575 allowed binding of RU486 to cPR. Substitution of this glycine by cysteine in the human PR (hPR) abrogated binding of RU486 but not that of an agonist. The corresponding mutation in the human glucocorticoid receptor resulted in a loss of binding of both dexamethasone and RU486. Examination of a series of 11β-substituted steroids showed that antagonism is not an intrinsic property of an antihormone, because one hPR antagonist acted as an agonist for a mutated hPR. The positioning of an aromatic 11β-substitution in the PR HBD appears to be critical for generating agonistic or antagonistic activity.
Diacylglycerol-Stimulated Formation of Actin Nucleation Sites at Plasma Membranes
Authors: Shariff Aneesa , Luna Elizabeth J.
Published: October 2006

Diacylglycerols, which are generated during phospholipase-catalyzed hydrolysis of phospholipids, stimulated actin polymerization in the presence of highly purified plasma membranes from the cellular slime mold
Dictyostelium discoideum
. The increased rate of actin polymerization apparently resulted from de novo formation of actin nucleation sites rather than uncapping of existing filament ends, because the membranes lacked detectable endogenous actin. The increased actin nucleation was mediated by a peripheral membrane component other than protein kinase C, the classical target of diacylglycerol action. These results indicate that diacylglycerols increase actin nucleation at plasma membranes and suggest a mechanism whereby signal transduction pathways may control cytoskeletal assembly.
Regulation of Plasma Membrane Recycling by CFTR
Authors: Bradbury Neil A. , Jilling Tamas , Berta Gabor , Sorscher Eric J. , Bridges Robert J. , Kirk Kevin L.
Published: October 2006

The gene that encodes the cystic fibrosis transmembrane conductance regulator (CFTR) is defective in patients with cystic fibrosis. Although the protein product of the CFTR gene has been proposed to function as a chloride ion channel, certain aspects of its function remain unclear. The role of CFTR in the adenosine 3′,5′-monophosphate (cAMP)-dependent regulation of plasma membrane recycling was examined. Adenosine 3′,5′-monophosphate is known to regulate endocytosis and exocytosis in chloride-secreting epithelial cells that express CFTR. However, mutant epithelial cells derived from a patient with cystic fibrosis exhibited no cAMP-dependent regulation of endocytosis and exocytosis until they were transfected with complementary DNA encoding wild-type CFTR. Thus, CFTR is critical for cAMP-dependent regulation of membrane recycling in epithelial tissues, and this function of CFTR could explain in part the pleiotropic nature of cystic fibrosis.
Role for c-myc in Activation-Induced Apoptotic Cell Death in T Cell Hybridomas
Authors: Shi Yufang , Glynn Jacqueline M. , Guilbert Lawrence J. , Cotter Thomas G. , Bissonnette Reid P. , Green Douglas R.
Published: October 2006

Immature T cells and some T cell hybridomas undergo apoptotic cell death when activated through the T cell receptor complex, a phenomenon that is probably related to antigen induced negative selection of developing T cells. This activation-induced apoptosis depends on active protein and RNA synthesis in the dying cells, although none of the genes required for this process have previously been identified. Antisense oligonucleotides corresponding to c-
myc
block the constitutive expression of c-Myc protein in T cell hybridomas and interfere with all aspects of activation-induced apoptosis without affecting lymphokine production in these cells. These data indicate that c-
myc
expression is a necessary component of activation-induced apoptosis.
Minimal Dosage of Iodide Required To Suppress Uptake of Iodine-131 by Normal Thyroid
Authors: Saxena Krishna M. , Chapman Earle M. , Pryles Charles V.
Published: October 2006

See related

editorial
.

Sodium iodide was given in increasing doses to mentally defective children with normal thyroid function. Maximal suppression of iodine-131 uptake was achieved with 1500 to 2000 micrograms of iodide per square meter of body surface per day, but quickly rebounded when iodide was discontinued. This minimal effective dose is important if countermeasures against fallout are employed.
Effect of Glucose on the Activity of Hypothalamic "Feeding Centers"
Authors: Anand B. K. , Chhina G. S. , Singh Baldev
Published: October 2006

The unit activity of the neurons in the hypothalamic "satiety" and "feeding" centers and adjacent control regions was recorded before and after intravenous injection of glucose. Increase in blood glucose and arteriovenous glucose difference (glucose utilization) increases the activity of satiety center neurons and slightly decreases the activity of feeding center neurons, without producing any significant change in the activity of control regions.
Evoked Responses to Clicks and Electroencephalographic Stages of Sleep in Man
Authors: Williams Harold L. , Tepas Donald I. , Morlock Henry C.
Published: October 2006

The form of the average evoked response to clicks is highly correlated with the background electroencephalogram. However, the response during the emergent low-voltage "dreaming" stage is different from that seen during the low-voltage phase at the beginning of sleep. The results provide additional evidence that the emergent low-voltage stage is a neurophysiologically unique phase.
Cholinergic Tracing of a Central Neural Circuit Underlying the Thirst Drive
Authors: Fisher Alan E. , Coury John N.
Published: October 2006

Cholinergic stimulation of any of a number of interrelated limbic and diencephalic structures in the rat elicits a rapid and marked increase in water intake. We postulate that a generalized Papez circuit mediates the thirst drive, that the circuit is specifically and functionally sensitive to cholinergic action, and that other primary drives depend on closely parallel neural circuits partitioned both structurally and biochemically.
Electron Microscopy of
Staphylococcus aureus
Treated with Tetracycline
Authors: Hash J. H. , Davies M. C.
Published: October 2006

After exposure to tetracycline,
Staphylococcus aureus
was fixed with formaldehyde and osmium tetroxide, thin-sectioned, and examined with the electron microscope. Compared with control cells, the tetracycline-treated cells had no transvers septa, were larger, had a greater electron density, and had thicker cell walls.
Hippocampal Ablation and Passive Avoidance
Authors: Isaacson Robert L. , Wickelgren Warren O.
Published: October 2006

Six rats with bilateral ablation of the hippocampus and six rats with extensive destruction of the neocortex were trained to enter a small compartment, while hungry, for a food reward. After 35 trials, spread over 4 days of training, the animals were given a shock while they were eating in the goal box. After the shock the rats with cortical lesions would not enter the goal compartment on the remainder of the trials given on the same day and only gradually began to re-enter over the next 2 days. The effect of the shock on the subjects with hippocampal ablation was slight and transient, suggesting that the ability to make passive avoidance responses was impaired.
Extreme Spindles: Correlation of Electroencephalographic Sleep Pattern with Mental Retardation
Authors: Gibbs Erna L. , Gibbs Frederic A.
Published: October 2006

An electroencephalographic abnormality is described which is relatively common among children below 12 years of age who are mentally retarded. This pattern consists of exaggerated sleep spindles, which are of higher voltage and more continuously present than in normal persons, and it correlates specifically with mental retardation and not with epilepsy or cerebral palsy.
Mapping a Field of Short-Time Visual Search
Authors: Chaikin Joyce D. , Corbin Horace H. , Volkmann John
Published: October 2006

The binocular field of vision during short-time search of a stimulus matrix was mapped and found to be ovaloid, with the longer axis horizontal and with the center of the field above the fixation point. The field expands in area as a function of exposure time, and there are frequent irregularities in its shape.
Isolation and Identification of the Sex Attractant of the American Cockroach
Authors: Jacobson Martin , Beroza Morton , Yamamoto Robert T.
Published: October 2006

The highly potent sex attractant of the female American cockroach,
Periplaneta americana
(L.), has been isolated in pure form and identified as 2,2-dimethyl-3-isopropylidenecyclopropyl propionate. The hydrogenated form of the attractant has been synthesized.
Fine Structure of the Interpseudotracheal Papillae of the Blowfly
Authors: Larsen Joseph R.
Published: October 2006

Electron-microscope studies of the interpseudotracheal papillae of the blowfly
Phormia regina
(Meigen) revealed that each papilla contains four nerve fibers. The nerve fibers are encased in a cuticular sheath located in the lumen of the papilla inside the vacuole of the trichogen cell.
Polymer Structure: Cross-Linking of a Polybenzimidazole
Authors: Gillham J. K.
Published: October 2006

The torsional braid technique was used to monitor the changes in rigidity and damping characteristics of a polybenzimidazole as it changes from a thermoplastic polymer to a thermoset resin at about 450°C. In an intermediate process the thermoplastic backbone of the polymer becomes flexible.
Predictors of Human Food Consumption
Authors: Pilgrim Francis J. , Kamen Joseph M.
Published: October 2006

Efficient psychological and nutritional measures by which food acceptance can be predicted were sought. Three-fourths of the variation in percentage of enlisted military personnel who take the foods at the serving table is predictable from knowledge of food preferences, the subjective satiety or "fillingness" of the food, and the amount of two major nutrients, fat and protein, the food contains.
Beading Phenomena of Mammalian Myelinated Nerve Fibers
Authors: Ochs Sidney
Published: October 2006

Fresh mammalian nerve, when subjected to a small stretch, shows a beading phenomenon. The larger fibers appear as a series of dilations and constrictions at intervals of 40 to 75 μ. Upon relaxation this beading is gone within a minute. The beading is not produced by the special technique of freeze-substitution used to show the phenomenon.
Mariner II: Preliminary Reports on Measurements of Venus: Magnetic Field
Authors: Smith E. J. , Davis Leverett , Coleman P. J. , Sonett C. P.
Published: October 2006

Mariner II magnetometer data gave no indication of a Venusian magnetic field. This implies, by comparison with spacecraft measurements near Earth and with theoretical models, that the magnetic dipole moment of Venus is at most 1/10 to 1/20 that of the earth.
Rotation of Venus: Period Estimated from Radar Measurements
Authors: Goldstein R. M. , Carpenter R. L.
Published: October 2006

Venus may rotate in a direction opposite to that of the earth at a rate of only one revolution in 240 days. The estimated period is accurate within 20 percent if the axis of rotation of Venus is perpendicular to the plane of the planet's orbit.
Plasma Corticosteroids: Changes in Concentration after Stimulation of Hippocampus and Amygdala
Authors: Mandell Arnold J. , Chapman Loring F. , Rand Robert W. , Walter Richard D.
Published: October 2006

Plasma 17-OH corticosteroid levels were determined before stimulation and at various intervals after stimulation in these limbic sites in patients in whom implanted electrodes had been placed during evaluation for surgical treatment of psychomotor epilepsy. Stimulation of the amygdala was followed by an elevation of plasma 17-hydroxycorticosteroids. Hippocampal stimulation resulted in a decreased corticosteroid level, followed in two instances by a secondary elevation.
The Physics of High-Field Superconductors
Authors: Bean Charles P. , Schmitt Roland W.
Published: October 2006

The recent burst of effort in the area of high-field superconductors has led to the construction of 70,000-oersted coils and the expectation that 100,000-oersted fields will be attained in the near future. The general theory suggests that fields above 300,000 oersteds are conceivable and that current densities of millions of amperes per square centimeter may be attained. Theory and experiment suggest that the upper critical field of materials such as Nb
3
Sn and Nb
.75
Zr
.25
is determined by their tendency to form a mixed state, and that a crucial question concerning their other properties is that of the interaction of this mixed state with imperfections. Lastly, it is possible to make a synthetic high-field superconductor by mechanically subdividing an ideal superconductor.
Participation of an Intermediate of Oxidative Phosphorylation in Ion Accumulation by Mitochondria
Authors: Brierley G. P. , Murer E. , Green D. E.
Published: October 2006

Heart mitochondria accumulate massive amounts of Mg
++
and phosphate or Ca
++
and phosphate when incubated under appropriate conditions. Studies with inhibitors of respiration, oligomycin, and uncouplers of oxidative phosphorylation indicate that the energy necessary for these reactions may be provided either in the form of ATP in the absence of electron transport, or in the form of a high-energy intermediate of oxidative phosphorylation, which operates even though ATP is not produced.
Microradiography of Fossilized Teeth
Authors: Wyckoff Ralph W. G. , Hoffmann Victor J. , Matter Philip
Published: October 2006

Microradiographic studies of fossil reptilian and amphibian teeth reveal an excellently preserved microstructure with little if any apparent mineralization except in the region of obvious fractures. X-ray diffraction has shown that the invading mineral near fractures is hematite, and x-ray spectroscopy has shown that relatively large amounts of yttrium are present.
Brown Fat: Thermogenic Effector of Arousal in Hibernators
Authors: Smith Robert E. , Hock Raymond J.
Published: October 2006

Earlier indications that brown fat has a thermogenic role in rats exposed to cold suggested that certain comparable functions in hibernating marmots be investigated. From the results it appears that arousal of the animal by cold is induced by sympathetically activated thermogenesis in areas of brown fat so located, relative to the vasculature, that heat is transferred to the thoracic structures and cervical spinal regions.
Cytochrome in
Thiobacillus thiooxidans
Authors: London Jack
Published: October 2006

Cytochrome is present in the autotrophic sulfur bacterium,
Thiobacillus thiooxidans
. As mediator in the final electron transfer to oxygen, the cytochrome participates in the oxidation of sulfur compounds by extracts of the organism.
Genetic Code: Emergence of a Symmetrical Pattern
Authors: Eck Richard V.
Published: October 2006

The triplets of nucleotides which apparently specify the detailed structure of proteins fall into a regular pattern: the 64 combinations of four nucleotides taken three at a time, are resolved into 32 pairs. The second member of each pair is identical with the first, except that in one position a purine is replaced by the other purine or a pyrimidine by the other pyrimidine. Almost all of the reported triplets fit into this pattern, and from it one can predict which amino acids will be found to correspond to the remaining 19 unidentified triplets. This pattern accounts for several of the observations concerning regularities in the data, partially determines the order of the nucleotides in each triplet, and suggests a structural basis for transfer RNA specificity.
Membrane Permeability: Monolayer Relationships
Authors: Shanes A. M.
Published: October 2006

A model of permeation of living membranes is proposed in which penetration by polar molecules takes place through islands composed of limited numbers of lipoidal molecules in a state comparable to that of certain compressed monolayers. These islands are visualized as scattered within a rigid, relatively impervious matrix. Relationships for penetration of monolayers by gases have been applied to this membrane model. Calculations on this basis demonstrate that the permeabilities relative to water are described at least as well by this model as by that assuming rigid pores of 4.25 Å radius.
Thermography of the Human Body
Authors: Barnes R. Bowling
Published: October 2006

Human skin is an almost perfect emitter of infrared radiation in the spectral region beyond 3 microns. This energy may be recorded as a thermogram to yield a quantitative temperature map of the skin. If the nude subject has remained quiet in a cool room for 10 to 15 minutes prior to thermography, the skin temperatures are determined largely by the vascularity of the skin itself and by the heat conducted from within the body. Since, under these conditions, the contrasts which appear arise essentially from the internal sources of heat, the resulting thermograms yield information concerning certain pathological conditions within the body.
Tracks of Charged Particles in High Polymers
Authors: Fleischer R. L. , Price P. B.
Published: October 2006

Heavily ionizing particles create trails of damage as they move through materials. In both addition and condensation polymers these trails can be selectively dissolved so that the sites and the directions taken by the moving particles are revealed. These materials thus serve as simple detectors of heavily charged particles.
Brown Fat: Thermogenic Effect during Arousal from Hibernation in the Bat
Authors: Smalley Robert L. , Dryer Robert L.
Published: October 2006

In the bat
Eptesicus fuscus
the temperature of brown fat exceeded that of other tissues by about 3°C during the late stages of arousal from hibernation. Heat production seems to be a major function of brown fat in the hibernating mammal.
Milker's Nodules: Isolation of a Poxvirus from a Human Case
Authors: Friedman-Kien Alvin E. , Rowe Wallace P. , Banfield William G.
Published: October 2006

A virus of the pox group was isolated from a lesion on a patient with milker's nodules by use of tissue cultures of bovine cells. The virus shows marked biologic and serologic differences from vaccinia virus, and it is presumably the etiologic agent of the milker's nodule syndrome.
Visual Reinforcement in Siamese Fighting Fish
Authors: Thompson Travis I.
Published: October 2006

Male Siamese fighting fish (
Betta splendens
) were conditioned to emit an instrumental response to obtain the visual image of another male of the species. The relative positive reinforcing effects of three visual stimuli capable of eliciting aggressive display were compared.
Memory in Mice as Affected by Intracerebral Puromycin
Authors: Flexner Josefa B. , Flexner Louis B. , Stellar Eliot
Published: October 2006

The antibiotic, puromycin, caused loss of memory of avoidance discrimination learning in mice when injected intracerebrally. Bilateral injections of puromycin involving the hippocampi and adjacent temporal cortices caused loss of short-term memory; consistent loss of longer-term memory required injections involving, in addition, most of the remaining cortices. Spread of the effective memory trace from the temporal-hippocampal areas to wide areas of the cortices appears to require 3 to 6 days, depending upon the individual animal. Recent reversal learning was lost while longer-term initial learning was retained after bilateral injections into the hippocampal-temporal areas.
Electrotonic Junctions between Teleost Spinal Neurons: Electrophysiology and Ultrastructure
Authors: Bennett M. V. L. , Aljure E. , Nakajima Y. , Pappas G. D.
Published: October 2006

Electrotonic transmission between spinal neurons is correlated with distinctive apposition of cell processes involving membrane fusion. In the same neurons, postsynaptic potentials appear to arise at typical synaptic knobs where there is an intercellular space.
Olfactory Receptor Response to the Cockroach Sexual Attractant
Authors: Boeckh Jurgen , Priesner Ernst , Schneider Dietrich , Jacobson Martin
Published: October 2006

The recently isolated sex attractant of the female American cockroach elicits an electrical response in the antennae of males, females, and nymphs of this species. These electroantennograms are known to be summated receptor (generator) potentials of many olfactory sensillae stimulated simultaneously. Many other odorous substances also elicit such responses in the cockroach antenna.
Experimental Diabetes Reduces Circulating 1,25-Dihydroxyvitamin D in the Rat
Authors: Schneider Louis E. , Schedl Harold P. , McCain Toni , Haussler Mark R.
Published: October 2006

Duodenal calcium absorption and a vitamin D-dependent duodenal calcium-binding protein are depressed in rats with alloxan- or streptozotocin-induced diabetes. To test for possible abnormal vitamin D metabolism in diabetes we measured serum concentrations of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D in control, streptozotocin diabetic, and insulin-treated diabetic rats. The serum concentration of 1,25-dihydroxyvitamin D was depressed in untreated diabetic rats to one-eighth of the level in controls and was restored to control levels by insulin treatment. The serum concentration of 25-hydroxyvitamin D was the same in all three groups. Hence, effects of diabetes on duodenal calcium transport can be explained by reduced concentrations of 1,25-dihydroxyvitamin D resulting either from failure of renal 1α-hydroxylation of 25-hydroxyvitamin D or increased catabolism of 1,25-dihydroxyvitamin D.