bluuebunny/crossref_metadata_2025 huggingface dataset:
Expression in
Escherichia coli
of a Chemically Synthesized Gene for the Hormone Somatostatin
Authors: Itakura Keiichi , Hirose Tadaaki , Crea Roberto , Riggs Arthur D. , Heyneker Herbert L. , Bolivar Francisco , Boyer Herbert W.
Published: October 2006

A gene for somatostatin, a mammalian peptide (14 amino acid residues) hormone, was synthesized by chemical methods. This gene was fused to the
Escherichia coli
β-galactosidase gene on the plasmid pBR322. Transformation of
E. coli
with the chimeric plasmid DNA led to the synthesis of a polypeptide including the sequence of amino acids corresponding to somatostatin. In vitro, active somatostatin was specifically cleaved from the large chimeric protein by treatment with cyanogen bromide. This represents the first synthesis of a functional polypeptide product from a gene of chemically synthesized origin.
Measurement of Regional Substrate Utilization Rates by Emission Tomography
Authors: Raichle M. E. , Welch M. J. , Grubb R. L. , Higgins C. S. , Ter-Pogossian M. M. , Larson K. B.
Published: October 2006

Emission tomography can be used to monitor, in vivo and regionally, the utilization of metabolic substrates labeled with positron-emitting radioisotopes produced by a cyclotron. The concept was validated by measuring brain glucose utilization with carbon-11-labeled glucose in rhesus monkeys.
Δ
9
-Tetrahydrocannabinol: Antiaggressive Effects in Mice, Rats, and Squirrel Monkeys
Authors: Miczek Klaus A.
Published: October 2006

Δ
9
-Tetrahydrocannabinol, the most active constituent of marihuana, decreased species-specific attack behavior in mice, rats, and squirrel monkeys at doses (0.25 to 2.0 milligram per kilogram of body weight) that have no effects on other elements of the behavioral repertoire. Aggressive behavior was engendered in all three species by confronting a resident animal with an intruder conspecific. The present results contrast with the widely held belief that marihuana increases aggressive behavior.
Care of the Aged: Old Problems in Need of New Solutions
Authors: Kane Robert L. , Kane Rosalie A.
Published: October 2006

Long-term care for the aged in the United States is overly dependent upon the nursing home. This hospital-like model for long-term care is particularly inappropriate since it imposes a medical solution on a variety of social problems. An adequate long-term care program requires a range of resources in the community as well as in institutions; sheltered housing options seem a desirable alternative to the nursing home. To ensure the quality of nursing home care, the present focus on setting standards for care activities should be abandoned in favor of a focus on care outcomes (physical, mental, and social). In an effort to change our present perverse incentives in the nursing home industry, the proposal is made that nursing homes be reimbursed according to the degree to which patient outcomes meet predicted outcomes.
Narcotic Analgesia: Fentanyl Reduces the Intensity But Not the Unpleasantness of Painful Tooth Pulp Sensations
Authors: Gracely Richard H. , Dubner Ronald , McGrath Patricia A.
Published: October 2006

Forty subjects rated the magnitude of painful electrical stimulation of tooth pulp before and after the intravenous administration of either fentanyl, a short-acting narcotic, or a saline placebo. The responses were choices of verbal descriptors from randomized lists of either sensory intensity (that is, weak, mild, intense) or unpleasantness (annoying, unpleasant, distressing) descriptors. The fentanyl significantly reduced the sensory intensity without reducing the unpleasantness of the tooth pulp stimuli, indicating that the mechanisms of narcotic analgesia may include a significant attenuation in pain sensation in addition to effects on pain reaction. These results stress the importance of using multiple measures of pain.
Lateral Geniculate Nucleus in Dark-Reared Cats: Loss of Y Cells Without Changes in Cell Size
Authors: Kratz Kenneth E. , Sherman S. Murray , Kalil Ronald
Published: October 2006

In cats reared in the dark from birth until 4 months of age, the dorsal lateral geniculate nucleus contained few normal Y cells in either the binocular or monocular segments. Although most of the neurons appeared to be normal X cells unaffected by light deprivation, many cells with abnormal receptive field and response characteristics were encountered. These effects were permanent, since 1 to 2 years of normal visual experience following initial light deprivation did not lead to any functional recovery. The sizes of cell bodies in cats reared in the dark were similar to those of normal animals, an indication that changes in geniculate cell physiology need not be related to changes in cell size.
Role of Nuclear Size in Cell Growth Initiation
Authors: Yen Andrew , Pardee Arthur B.
Published: October 2006

Swiss 3T3 cells arrested in G
0
(quiescent state) by reducing serum content of the medium all contain the same amount of DNA but vary in nuclear volume over approximately a twofold range. By use of flow microfluorimetry, scatterplots of nuclear volume versus DNA content were obtained in intervals after serum stimulation. The earliest cells to enter DNA synthesis were those with the largest nuclei, whereas cells with the smallest nuclei were among the latest. Regulation of cellular transit from G
0
to the S phase was therefore, at least in part, deterministic, since all G
0
cells did not have equal probabilities of entry into S at a given moment. All cells having the same nuclear volume did not initiate DNA synthesis at the same moment; therefore, factors other than nuclear volume must also influence this timing. Nuclear volume correlated with the maximum rate at which cells could enter S. The kinetic model of the cell cycle postulating a probabilistic event as solely responsible for entry into S thus appears too simple.
Development of the Capacity for Tactile Information Transfer Between Hemispheres in Normal Children
Authors: Galin David , Johnstone Jack , Nakell Linda , Herron Jeannine
Published: October 2006

The hypothesis of less direct interaction between hemispheres in young children was supported by a behavioral test. Fabric samples were compared with either the same hand (same hemisphere) or with opposite hands (between hemispheres). Crossed errors were a significantly larger proportion of total errors in 3-year-olds than in 5-year-olds.
Low Urinary Estrogen Glucuronides in Women at Risk for Familial Breast Cancer
Authors: Fishman Jack , Fukushima David K. , O'Connor John , Lynch Henry T.
Published: October 2006

Daily (12-hour) urine collections taken throughout the menstrual cycle were obtained from 30 young women who by genetic analysis were at risk for familial breast cancer, and from 30 control women carefully matched for age, height, and reproductive history. Steroids in the urine were extracted by glucuronidase hydrolysis, and the primary glucocorticoid, androgen, and estrogen hormones and their metabolites were measured by radioimmunoassay. Highly significant differences were observed only in the case of estrone and estradiol, with the high-risk subjects exhibiting lower values than the controls. This endocrine abnormality in young women at risk for breast cancer may be a potential discriminant for identifying women at risk for the disease in the population at large.
Automatic Classification of Electroencephalograms: Kullback-Leibler Nearest Neighbor Rules
Authors: Gersch Will , Martinelli F. , Yonemoto J. , Low M. D. , McEwan J. A.
Published: October 2006

A prototypic problem in screening of electroencephalograms in the automatic classification of stationary electroencephalogram time series is treated here by the Kullback-Leibler nearest neighbor rule approach. In that problem, the category or state of an individual is classified by comparison of his or her electroencephalogram with those taken from other individuals in the alternative categories. The Kullback-Leibler nearest neighbor classification rules yield a statistically reliable estimate of the smallest possible probability of electroencephalogram misclassification with a relatively small number of labeled sample electroencephalograms. The automatic classification of anesthesia levels L1 and L3, respectively the anesthesia levels insufficient and sufficient for deep surgery, is treated by machine computation on the electroencephalogram alone.
Opiate Antagonists: A Role in the Treatment of Hypovolemic Shock
Authors: Faden Alan I. , Holaday John W.
Published: October 2006

The opiate antagonist naloxone has been used to treat shock following acute blood loss in conscious rats. Naloxone treatment rapidly increased mean arterial pressure and pulse pressure in this new shock model. More importantly, these blood pressure changes were sustained and survival was significantly increased with naloxone as compared with placebo treatment. From these findings, it may be inferred that endorphins may play a role in the pathophysiology of hypovolemic shock. It is suggested that narcotic antagonists may prove to be of therapeutic value in the treatment of shock.
Reptiles and Mammals Use Similar Sensory Organizations in the Midbrain
Authors: Gaither Neal S. , Stein Barry E.
Published: October 2006

Striking similarities were observed between the overlapping visual and tactile maps of the mammalian superior colliculus and of its homolog in reptiles, the optic tectum. This topographic pattern probably represents a plan of sensory representation that existed in ancient reptiles and that was retained during the evolution to mammalian forms more than 180 million years ago.
Dynamics of Skeletal Pattern Formation in Developing Chick Limb
Authors: Newman Stuart A. , Frisch H. L.
Published: October 2006

During development of the embryonic chick limb the skeletal pattern is laid out as cartilaginous primordia, which emerge in a proximodistal sequence over a period of 4 days. The differentiation of cartilage is preceded by changes in cellular contacts at specific locations in the precartilage mesenchyme. Under realistic assumptions, the biosynthesis and diffusion through the extracellular matrix of a cell surface protein, such as fibronectin, will lead to spatial patterns of this molecule that could be the basis of the emergent primordia. As cellular differentiation proceeds, the size of the mesenchymal diffusion chamber is reduced in discrete steps, leading to sequential reorganizations of the morphogen pattern. The successive patterns correspond to observed rows of skeletal elements, whose emergence, in theory and in practice, depends on the maintenance of a unique boundary condition at the limb bud apex.
Differences in Neural Organization Between Individuals with Inverted and Noninverted Handwriting Postures
Authors: Moscovitch Morris , Smith Lee C.
Published: October 2006

Levy's hypothesis that movements of the distal musculature are controlled by ipsilateral motor projections in subjects with inverted writing posture was tested in a reaction-time experiment with lateralized auditory, tactual, and visual stimulation. Subjects were required to depress a response key with the left or right index finger when they detected a stimulus in either the left or right sensory field. Writers with noninverted posture responded quickest to stimuli on the same side as the responding hand in all modalities tested, whereas inverted writers showed this pattern only in auditory and tactual modalities. In the visual modality, they responded quickest to stimuli on the side opposite the responding hand. Because Levy's hypothesis predicts the latter effect in all modalities for inverted writers, it is challenged by our results, which suggest that inverted writers may be characterized by anomalous visual or visuomotor organization.
Memory Load and Event Rate Control Sensitivity Decrements in Sustained Attention
Authors: Parasuraman Raja
Published: October 2006

The capacity to sustain attention at an efficient level deteriorates over time in discrimination and monitoring tasks. This "vigilance decrement" results from a decrement in perceptual sensitivity only if (i) target discrimination loads memory and (ii) stimulus events occur rapidly; otherwise, the decrement reflects temporal changes in response criteria. These results provide a basis for distinguishing between the perceptual and response processes underlying the vigilance decrement that may be generalized across a range of tasks.
Lithium Transport Across Red Cell Membrane: A Cell Membrane Abnormality in Manic-Depressive Illness
Authors: Dorus Elizabeth , Pandey Ghanshyam N. , Shaughnessy Rita , Gaviria Moises , Val Eduardo , Ericksen Stephen , Davis John M.
Published: October 2006

In the families of manic-depressive patients, relatives with a history of affective disorders had a significantly higher ratio of mean red cell lithium to plasma lithium in vitro than relatives with no such history. A genetically controlled abnormality in lithium-sodium transport, the mechanism that determines the lithium ratio, may play a role in the etiology of some forms of affective disorders.
Cerebral Norepinephrine: Influence on Cortical Oxidative Metabolism in Situ
Authors: Harik Sami I. , LaManna Joseph C. , Light Andrew I. , Rosenthal Myron
Published: October 2006

Unilateral lesion of the locus coeruleus and the resultant norepinephrine depletion in the ipsilateral cerebrum alters the relationship between cerebral metabolic demands and local delivery of oxygen and substrates. This effect of norepinephrine depletion is demonstrated by slower recovery of the redox ratio of cytochromea,a3during increased metabolic demands induced by local cortical stimulation.
Response of Cat Inferior Colliculus Neurons to Binaural Beat Stimuli: Possible Mechanisms for Sound Localization
Authors: Kuwada Shigeyuki , Yin Tom C. T. , Wickesberg Robert E.
Published: October 2006

The interaural phase sensitivity of neurons was studied through the use of binaural beat stimuli. The response of most cells was phase-locked to the beat frequency, which provides a possible neural correlate to the human sensation of binaural beats. In addition, this stimulus allowed the direction and rate of interaural phase change to be varied. Some neurons in our sample responded selectively to manipulations of these two variables, which suggests a sensitivity to direction or speed of movement.
Phase Resetting and Annihilation of Pacemaker Activity in Cardiac Tissue
Authors: Jalife Jose , Antzelevitch Charles
Published: October 2006

Spontaneous rhythmic activity in isolated cardiac pacemaker cells can be terminated by a brief, subthreshold, depolarizing or hyperpolarizing perturbation of the proper magnitude applied at a specific point in the pacemaker cycle. Evidence is provided in support of a topological theory of the existence of a "singular" point in cardiac oscillators.
Calcitonin: Inhibitory Effect on Eating in Rats
Authors: Freed William J. , Perlow Mark J. , Wyatt Richard Jed
Published: October 2006

Subcutaneous and intracerebral injections of calcitonin inhibited feeding in rats. The anorectic activity of calcitonin was destroyed by exposing the hormone to heat, trypsin, or hydrogen peroxide. Calcitonin did not produce a conditioned taste aversion to saccharin, and maximum inhibition of feeding occurred 4.5 to 8.3 hours after subcutaneous administration. It is concluded that calcitonin inhibits feeding by acting directly on the central nervous system.
Pyruvate Dehydrogenase Activation in Adipocyte Mitochondria by an Insulin-Generated Mediator from Muscle
Authors: Jarett L. , Seals J. R.
Published: October 2006

Material in a chromatographic fraction from an extract of insulin-treated muscle stimulated pyruvate dehydrogenase activity in adipocyte mitochondria. This action was similar to insulin's activation of the enzyme in a plasma membrane-mitochondria mixture. Neither the chromatographic fraction nor insulin required adenosine triphosphate or magnesium ion (Mg
2+
), suggesting that both agents acted through a calcium-sensitive phosphatase. This fraction may contain a chemical mediator of insulin action.
Pheromonally Induced Sexual Maturation in Females: Regulation by the Social Environment of the Male
Authors: Lombardi Joseph R. , Vandenbergh John G.
Published: October 2006

Social subordination, which suppresses gonadal function in juvenile and adult male house mice, also suppresses the activity of an androgen-dependent urinary pheromone that accelerates the rate of sexual maturation in juvenile females. Pheromone production may also be suppressed by the presence of pregnant or lactating females. This suggests that the social environment may influence the fertility of population females by altering urinary pheromone activity in the male.
Licking Behavior: Evidence of Hypoglossal Oscillator
Authors: Wiesenfeld Zsuzsanna , Halpern Bruce P. , Tapper Daniel N.
Published: October 2006

Action potentials and slow waves were recorded from the hypoglossal nucleus of rats during licking of water from a drinking tube. Periods of licking and of rhythmic neural activity were usually highly correlated, as were their frequencies. Neural activity sometimes continued after cessation of licking; at other times, it stopped during a short interruption of licking and resumed in rhythm with licking. These observations are consistent with an oscillatory model of the control of licking.
Premenstrual Symptoms: A Reinterpretation
Authors: Ruble Diane N.
Published: October 2006

Conclusions regarding the physiological basis and disruptive effects of premenstrual symptoms may be biased because of the reliance on self-report questionnaires as a source of data. In order to examine this possible bias, women's perceptions of their cycle phase were separated experimentally from actual cycle phase. Women who were led to believe that they were premenstrual reported experiencing a significantly higher degree of several physical symptoms, such as water retention, than did women who were led to believe they were intermenstrual. Thus, because of these psychosocial influences on symptom reports, it seems necessary to reexamine previous conclusions regarding the magnitude of menstrual-related changes as well as their physiological basis.
Secondary Structure of Histones and DNA in Chromatin
Authors: Thomas G. J. , Prescott B. , Olins D. E.
Published: October 2006

Laser Raman spectroscopy indicates that the inner histones which are bound to DNA in chromatin or in isolated nu bodies are similar in conformation to the inner histones which are dissociated from DNA in high-salt solutions. This structure contains, on the average, 51 ± 5 percent α-helix and no substantial β-sheet conformation. It is proposed that the protein core of the nu body has a high α-helix content.
Bone Cells: A Serum-Free Medium Supports Proliferation in Primary Culture
Authors: Burns James K. , Peck William A.
Published: October 2006

Bone cells isolated from embryonic rat calvaria increase in number two- to threefold when cultured at high, but not at low, population densities in a serum-free medium that contains albumin. Cultured cells respond to parathyroid hormone and exhibit a marked rise in alkaline phosphatase activity during proliferation, which suggests the progressive differentiation or preferential growth of osteoblast-like cells.
Compulsive, Abnormal Walking Caused by Anticholinergics in Akinetic, 6-Hydroxydopamine-Treated Rats
Authors: Schallert Timothy , Whishaw Ian Q. , Ramirez Victor D. , Teitelbaum Philip
Published: October 2006

In otherwise profoundly akinetic rats that had been severely depleted of brain catecholamines, anticholinergic drugs caused excessive walking. The effect did not appear until 10 days after surgery and then increased with time, suggesting that a phenomenon analogous to denervation supersensitivity may be involved. If the animals walked into corners, they were unable to turn around or back out. Their gait (extremely short steps) was reminiscent of that of patients with Parkinson's disease. The results are consistent with a mutually antagonistic interaction between cholinergic and dopaminergic brain systems and emphasize certain complexities in this interaction.
Phagocytosis of Light- and Dark-Adapted Rod Outer Segments by Cultured Pigment Epithelium
Authors: Hall Michael O.
Published: October 2006

Pigment epithelial cells in culture retain their ability to phagocytize rod outer segments. These cells phagocytize rod outer segments isolated from light-adapted rats, or from dark-adapted rats killed after the time at which the lights would normally be turned on. However, they phagocytize far fewer rod outer segments prepared in the dark from the retinas of rats killed before the onset of the normal light cycle. Phagocytosis of dark rod outer segments is variable, but that of light outer segments is reproducible. It is postulated that the effect of light is to synchronize the chemical events that occur at the surface of the rods to prepare them for phagocytosis. These processes also occur in the dark, but more slowly and irregularly than in the light.
Long-Term Analgesic Effects of Inescapable Shock and Learned Helplessness
Authors: Jackson Raymond L. , Maier Steven F. , Coon Deborah J.
Published: October 2006

Although exposure to inescapable shocks induced analgesia in rats, the analgesia was not manifest 24 hours later. A brief reexposure to shock, however, restored the analgesia. This reexposure to shock had an analgesic effect only if the rats had been shocked 24 hours previously. Further, long-term analgesic effects depended on the controllability of the original shocks and not on shock exposure per se. Implications of these results for learned helplessness and stress-induced analgesia are discussed.
Echinomycin Binding Sites on DNA
Authors: Van Dyke Michael M. , Dervan Peter B.
Published: October 2006

The preferred binding sites of echinomycin on DNA can be determined by a method called "footprinting." A
32
P end-labeled restriction fragment from pBR322 DNA is protected by binding to echinomycin, and cleaved by a synthetic DNA cleaving reagent, methidiumpropyl--EDTA⋅Fe(II); the DNA cleavage products are then subjected to high-resolution gel analyses. This method reveals that echinomycin has a binding site size of four base pairs. The strong binding sites for echinomycin contain the central two-base-pair sequence 5′-CG-3′. From an analysis of 15 echinomycin sites on 210 base pairs of DNA, key recognition elements for echinomycin are contained in the sequences (5′-3′) ACGT and TCGT (A, adenine; C, cytosine; G, guanine; T, thymine).
JC Virus Enhancer-Promoter Active in Human Brain Cells
Authors: Kenney Shannon , Natarajan Venkatachala , Strike David , Khoury George , Salzman Norman P.
Published: October 2006

A human papovavirus, JCV, is the etiologic agent of the fatal demyelinating disease, progressive multifocal leukoencephalopathy. The JCV 98-base-pair tandem repeats, located to the late side of the viral replication origin, were shown to be a transcriptional regulatory element with enhancer-like activity in human fetal glial cells. These tandem repeats share significant homology with the 82-nucleotide rat brain-specific identifier RNA sequence.
Evidence for L-glutamate as the Neurotransmitter of Baroreceptor Afferent Nerve Fibers
Authors: Talman William T. , Perrone Mark H. , Reis Donald J.
Published: October 2006

Microinjection of L-glutamate into the intermediate nucleus tractus solitarii in anesthetized rats elicits hypotension, bradycardia, and apnea, simulating baroreceptor reflexes. Ablation of the nodose ganglion results in selective reduction of high-affinity uptake of L-glutanate in the nucleus tractus solitarii. L-Glutamate may be the neurotransmitter of afferent nerve fibers from arterial baroreceptors.
Impulse Activity Differentially Regulates [Leu]Enkephalin and Catecholamine Characters in the Adrenal Medulla
Authors: LaGamma Edmund F. , Adler Joshua E. , Black Ira B.
Published: October 2006

Regulation of the putative peptide neurohumour [Leu]enkephalin and the catecholaminergic enzymes tyrosine hydroxylase and phenylethanolamine-N-methyl-transferase was examined in the rat adrenal medulla in vivo and in vitro. Surgical denervation of the adrenal gland or pharmacologic blockade of synaptic transmission, treatments known to decrease catecholamine traits, increased [Leu]enkephalin content. Medullas explanted to culture exhibited a 50-fold rise in [Leu]enkephalin in 4 days, whereas tyrosine hydroxylase remained constant, and phenylethanolamine-N-methyltransferase decreased to a new baseline level. Veratridine-induced depolarization prevented the accumulation of [Leu]enkephalin, an effect that was blocked by tetrodotoxin, which antagonizes transmembrane Na
+
influx. These studies suggest that enkephalinergic and catecholamine characters are differentially regulated by impulse activity and depolarization in the adrenal medulla.
Epidermal Growth Factor Immunoreactive Material in the Central Nervous System: Location and Development
Authors: Fallon James H. , Seroogy Kim B. , Loughlin Sandra E. , Morrison Richard S. , Bradshaw Ralph A. , Knaver Daniel J. , Cunningham Dennis D.
Published: October 2006

Epidermal growth factor (EGF) is a potent mitogen with hormonal activity in the gastrointestinal tract. Material cross-reacting with EGF was detected in the central nervous system of the developing and adult albino rat by the indirect immunofluorescence technique. High concentrations of EGF-cross-reacting material were identified in forebrain and midbrain structures of pallidal areas of the brain. These include the globus pallidus, ventral pallidum, entopeduncular nucleus, substantia nigra pars reticulata, and the islands of Calleja. Thus, EGF may represent another gut-brain peptide with potential neurotransmitter-neuromodulator functions in pallidal structures of the extrapyramidal motor systems of the brain.
Transglutaminase-Mediated Modifications of the Rat Sperm Surface in Vitro
Authors: Paonessa G. , Metafora S. , Tajana G. , Abrescia P. , De Santis A. , Gentile V. , Porta R.
Published: October 2006

Two transglutaminase-mediated modifications of the rat epididymal spermatozoon surface were demonstrated in vitro. Transglutaminase was effective in promoting the binding of spermidine to the sperm. Moreover, the enzyme, by reacting with one of the major proteins secreted by the rat seminal vesicle epithelium, produced a modified form of the protein with a higher molecular weight and the capability of binding to the sperm cells. A specific physiological role for the enzyme, bringing about modifications of the rat sperm surface in the seminal fluid environment, is suggested.
Antiallergic Drug Cromolyn May Inhibit Histamine Secretion by Regulating Phosphorylation of a Mast Cell Protein
Authors: Theoharides Theoharis C. , Sieghart Werner , Greengard Paul , Douglas William W.
Published: October 2006

Cromolyn inhibited histamine release from mast cells that was induced by a classic secretagogue and correspondingly increased incorporation of radioactive phosphate into a 78,000-dalton protein. These effects on histamine secretion and on protein phosphorylation were rapid in onset and both showed tachyphylaxis. Cromolyn may therefore act by altering the phosphorylation of a protein involved in the regulation of secretion.
Deficient Natural Killer Cell Activity in X-Linked Lymphoproliferative Syndrome
Authors: Sullivan John L. , Byron Kevin S. , Brewster Frank E. , Purtilo David T.
Published: October 2006

The activity of natural killer cells was found to be deficient in 10 of 12 males with X-linked lymphoproliferative syndrome, a life-threatening proliferation of lymphocytes after infection by Epstein-Barr virus. The activity levels of natural killer cells from affected males were increased after treatment with interferon in vitro, but normal levels of killing were not obtained. Deficient activity of killer cells in individuals with immunodeficiency and chronic infection by Epstein-Barr virus may contribute to the development of lymphoproliferative disorders.
Sexual Differentiation of the Central Nervous System
Authors: MacLusky Neil J. , Naftolin Frederick
Published: October 2006

Sexual differentiation of reproductive and behavior patterns is largely effected by hormones produced by the gonads. In many higher vertebrates, an integral part of this process is the induction of permanent and essentially irreversible sex differences in central nervous function, in response to gonadal hormones secreted early in development.
Intrathecal Interferon Reduces Exacerbations of Multiple Sclerosis
Authors: Jacobs Lawrence , O'Malley Judith , Freeman Arnold , Ekes Roslyn
Published: October 2006

Ten patients with multiple sclerosis who were treated with human fibroblast interferon (IFN-B) for 6 months showed a significant reduction in their exacerbation rates compared with their rates before treatment (P < .01). The IFN-B was administered intrathecally by serial lumbar punctures. There was no significant change in the exacerbation rates of ten multiple sclerosis control patients before and during the period of observation. The IFN-B recipients have now been on the study a mean of 1.5 years, the controls, 1.2 years. The clinical condition of five of the IFN-B recipients and one of the control patients has improved, whereas the condition of five of the controls and one of the IFN-B recipients has deteriorated (P < .036). These findings warrant cautious optimism about the efficacy of intrathecal IFN-B in altering the course of multiple sclerosis and support concepts of a viral or dysimmune etiology of the disease.
Substance P Analog, DiMe-C7: Evidence for Stability in Rat Brain and Prolonged Central Actions
Authors: Eison A. S. , Iversen S. D. , Sandberg B. E. B. , Watson S. P. , Hanley M. R. , Iversen L. L.
Published: October 2006

A metabolically protected analog of substance P, [pGlu
5
-MePhe
8
-MeGly
9
]SP(5-11) (DiMe-C7), was approximately equipotent with substance P in causing increased locomotor activity after microinfusion into the ventral tegmental area of rat brain, but the effects of DiMe-C7 on behavior were considerably prolonged. There was little metabolic degradation of tritiated DiMe-C7 for up to 1 hour after infusion, whereas tritiated substance P was completely degraded within 10 minutes.
High Efficiency Latency and Activation of Herpes Simplex Virus in Human Cells
Authors: Wigdahl Brian L. , Scheck Adrienne C. , De Clercq Erik , Rapp Fred
Published: October 2006

Herpes simplex virus (HSV) exists in humans in a latent form that can be activated. To characterize the molecular basis of the cell-virus interactions and to analyze the state of the latent HSV genome, an in vitro model system was established. In this system a large fraction of the latently infected cells contain an HSV genome that can be activated. Cell survival was reduced minimally after repression of high multiplicity HSV type 1 (HSV-1) infection of human fibroblast cells with (E)-5-(2-bromovinyl)-2′-deoxyuridine in combination with human leukocyte interferon (IFN-α). A minimum of 1 to 3 percent of the surviving cells contained an HSV genome that could be activated either by human cytomegalovirus superinfection or reduction in incubation temperature.
Evidence That Glucose "Marks" β Cells Resulting in Preferential Release of Newly Synthesized Insulin
Authors: Gold Gerald , Gishizky Mikhail L. , Grodsky Gerold M.
Published: October 2006

Studies of isolated islets labeled with radioactive leucine show that glucose at a critical time "marks" islets in such a way as to cause preferential release of newly synthesized insulin. The preferential release of insulin from marked islets is relatively independent of subsequent secretagogues or rates of insulin secretion. Previous kinetic studies have indicated that the critical time at which marking occurs is after proinsulin biosynthesis but before the secretory event. Thus, secretory cells may regulate the diversion of newly synthesized material for immediate release as it is approaching or transiting the Golgi apparatus.
Antibodies That React with Predetermined Sites on Proteins
Authors: Sutcliffe J. Gregor , Shinnick Thomas M. , Green Nicola , Lerner Richard A.
Published: October 2006

Contrary to previous predictions, relatively short synthetic peptides that mimic part of a protein sequence are routinely capable of eliciting an antiserum that reacts with the partially mimicked protein. Peptides capable of eliciting protein-reactive serums are frequently represented in the primary sequence of a protein, can be characterized by a set of simple chemical rules, and are confined neither to immunodominant regions of intact proteins nor to the amino or carboxyl terminals. As such, synthetic peptide immunogens are valuable for eliciting reagents with predetermined specificity that can be used for basic research. In addition, some synthetic peptides are capable of mimicking regions of virus proteins and eliciting immune responses in animals that are protective against the viral agents. Such peptides may thus serve as the basis for safe, chemically defined synthetic vaccines.
Antibody to Hepatitis B Virus Induced by Injecting Antibodies to the Idiotype
Authors: Kennedy R. C. , Melnick J. L. , Dreesman G. R.
Published: October 2006

Anti-idiotype reagents that recognize a common idiotype associated with antibody to hepatitis B surface antigen (anti-HBs) were used to induce anti-HBs in mice. The anti-idiotype-induced anti-HBs was found to recognize the group-specific
a
determinant of hepatitis B surface antigen and to express an interspecies idiotype. These findings suggest that anti-idiotypes may be useful as vaccines or vaccine primers.
The Production of Pure Absolute Alcohol with Calcium Carbide and Anhydrous Copper Sulphate
Authors: Lyons R. E. , Smith L. T.
Published: October 2006

(1) The above is recommended as an economical, convenient and quick method for producing absolute alcohol on a laboratory scale.

If the distillation is executed with free flame, excessive or careless heating must be avoided near the end of the operation because of the copper acetylide in the residue.

(2) Calcium carbide is recommended over potassium permanganate or anhydrous copper sulphate as a qualitative reagent in detecting traces of water in alcohol.
Detection, Isolation, and Continuous Production of Cytopathic Retroviruses (HTLV-III) from Patients with AIDS and Pre-AIDS
Authors: Popovic Mikulas , Sarngadharan M. G. , Read Elizabeth , Gallo Robert C.
Published: October 2006

A cell system was developed for the reproducible detection of human T-lymphotropic retroviruses (HTLV family) from patients with the acquired immunodeficiency syndrome (AIDS) or with signs or symptoms that frequently precede AIDS (pre-AIDS). The cells are specific clones from a permissive human neoplastic T-cell line. Some of the clones permanently grow and continuously produce large amounts of virus after infection with cytopathic (HTLV-III) variants of these viruses. One cytopathic effect of HTLV-III in this system is the arrangement of multiple nuclei in a characteristic ring formation in giant cells of the infected T-cell population. These structures can be used as an indicator to detect HTLV-III in clinical specimens. This system opens the way to the routine detection of HTLV-III and related cytopathic variants of HTLV in patients with AIDS or pre-AIDS and in healthy carriers, and it provides large amounts of virus for detailed molecular and immunological analyses.
Leupeptin, a Protease Inhibitor, Decreases Protein Degradation in Normal and Diseased Muscles
Authors: Libby Peter , Goldberg Alfred L.
Published: October 2006

The protease inhibitor leupeptin decreases protein degradation in rat skeletal and cardiac muscle incubated in vitro, while protein synthesis remains unaltered. Leupeptin also lowers protein breakdown in denervated rat muscles and affected muscles from mice with hereditary muscular dystrophy. Leupeptin may thus be useful in retarding tissue atrophy. Since homogenates of leupeptin-treated muscles had decreased cathepsin B activity, this lysosomal protease may play a role in protein turnover in normal and diseased muscles.
Phase Sensitivity in Electroreception
Authors: Heiligenberg Walter , Altes Richard A.
Published: October 2006

The gymnotoid electric fish
Hypopomus artedi
discriminates between electric stimulus pulses with identical spectral amplitudes but different spectral phase functions. Behavioral results can be explained on the assumption that electroreception is based on a linear filter, approximately matched to the species' electric organ discharge. The impulse response of the appropriate matched filter, in fact, resembles the known impulse response of the electroreceptors involved.
Relative Risks of Saccharin and Calorie Ingestion
Authors: Cohen Bernard L.
Published: October 2006

The risk of a person getting cancer from ingesting saccharin is compared with the risk of ingesting additional calories which cause excess body weight. It is found that, for a person who is 10 percent overweight, the risk of ingesting one diet soft drink, which would cause a decrease in life expectancy of 9 seconds, is approximately equal to the risk of ingesting one additional kilocalorie; that is, if ingesting a diet drink inhibits ingestion of more than 1 kilocalorie, its benefits exceed its risks.
Calmodulin Plays a Pivotal Role in Cellular Regulation
Authors: Cheung Wai Yiu
Published: October 2006

The role of calcium ions (Ca
2+
) in cell functions is beginning to be unraveled at the molecular level as a result of recent research on calcium-binding proteins and particularly on calmodulin. These proteins interact reversibly with Ca
2+
to form a protein ⋅ Ca
2+
complex, whose activity is regulated by the cellular flux of Ca
2+
. Many of the effects of Ca
2+
appear to be exerted through calmodulin-regulated enzymes.
J Genes for Heavy Chain Immunoglobulins of Mouse
Authors: Newell Nanette , Richards Julia E. , Tucker Philip W. , Blattner Frederick R.
Published: October 2006

A 15,8-kilobase pair fragment of BALB/c mouse liver DNA, cloned in the Charon 4Aλ phage vector system, was shown to contain the μ heavy chain constant region (C
H
μ) gene for the mouse immunoglobulin M. In addition, this fragment of DNA contains at least two J genes, used to code for the carboxyl terminal portion of heavy chain variable regions. These genes are located in genomic DNA about eight kilobase pairs to the 5 ′ side of the C
H
μ gene. The complete nucleotide sequence of a 1120-base pair stretch of DNA that includes the two J genes has been determined.
Phase Variation: Evolution of a Controlling Element
Authors: Simon Melvin , Zieg Janine , Silverman Michael , Mandel Gail , Doolittle Russell
Published: October 2006

Phase variation in bacteria is regulated by homologous recombination at a specific DNA site. This recombinational event causes the inversion of a 970-base-pair DNA sequence that includes the promoter necessary for transcription of a flagellar gene. The invertible segment is flanked by two sites that are necessary for the inversion and contains a gene (
hin
) whose product mediates the inversion event. The
hin
gene shows extensive homology with the TnpR gene carried on the Tn3 transposon. It is also homologous with the
gin
gene carried on bacteriophage mu. These relationships suggest that the phase variation system may have evolved by the association of a transposon with a resident gene and the subsequent specialization of these elements to regulate flagellar antigen expression.
Long-Term Antidepressant Treatment Decreases Spiroperidol-Labeled Serotonin Receptor Binding
Authors: Peroutka Stephen J. , Snyder Solomon H.
Published: October 2006

Antidepressants compete at several neurotransmitter receptor binding sites, but drug affinities do not correlate with clinical efficacy. Long-term, but not short-term, antidepressant treatment decreases the numbers of both serotonin and β-adrenergic receptors. The decrease in the number of receptor sites is most marked for [
3
H]spiroperidol-labeled serotonin receptors and is characteristic for antidepressants of several classes.
Latency of Herpes Simplex Virus in Absence of Neutralizing Antibody: Model for Reactivation
Authors: Sekizawa Tsuyoshi , Openshaw Harry , Wohlenberg Charles , Notkins Abner Louis
Published: October 2006

Mice inoculated with herpes simplex virus (type 1) by the lip or corneal route and then passively immunized with rabbit antibody to herpes simplex virus developed a latent infection in the trigeminal ganglia within 96 hours. Neutralizing antibody to herpes simplex virus was cleared from the circulation and could not be detected in most of these mice after 2 months. Examination of ganglia from the antibody-negative mice revealed latent virus in over 90 percent of the animals, indicating that serum neutralizing antibody is not necessary to maintain the latent state. When the lips or corneas of these mice were traumatized, viral reactivation occurred in up to 90 percent of the mice, as demonstrated by the appearance of neutralizing antibody. This study provides a model for identifying factors that trigger viral reactivation.
Opiate Receptor Gradients in Monkey Cerebral Cortex: Correspondence with Sensory Processing Hierarchies
Authors: Lewis Michael E. , Mishkin Mortimer , Bragin Evgeni , Brown Roger M. , Pert Candace B. , Pert Agu
Published: October 2006

In order to obtain information on the possible functions of endogenous opiates in the primate cerebral cortex, we assessed the distribution of μ-like opiate receptors (which selectively bind
3
H-labeled naloxone) and δ-like opiate receptors (which selectively bind
3
H-labeled D-Ala
2
, D-Leu
5
-enkephalin) throughout the cerebral cortex of the rhesus monkey. Stereospecific [
3
H]naloxone binding sites increased in a gradient along hierarchically organized cortical systems that sequentially process modality-specific sensory information of a progressively more complex nature. Specific [
3
H]enkephalin binding sites, in contrast, were relatively evenly distributed throughout the cerebral cortex. These results, in combination with electrophysiological studies of monkeys and humans, suggest that μ-like opiate receptors may play a role in the affective filtering of sensory stimuli at the cortical level, that is, in emotion-induced selective attention.
Somatomedin-C Mediates Growth Hormone Negative Feedback by Effects on Both the Hypothalamus and the Pituitary
Authors: Berelowitz Michael , Szabo Marta , Frohman Lawrence A. , Firestone Susan , Chu Lily , Hintz Raymond L.
Published: October 2006

Somatomedin-C stimulates somatostatin release to a maximum of 390 percent of basal release during short-term (20-minute) incubation of rat hypothalamus. It has no effect on basal or stimulated growth hormone release from primary cultures of rat adenohypophyseal cells during a 4-hour incubation, but inhibits stimulated release by more than 90 percent after 24 hours. These findings suggest that somatomedin-C participates in the growth hormone negative feedback loop with an immediate effect on hypothalamic somatostatin and a delayed effect on the anterior pituitary.
Gonadotropin-Releasing Hormone Receptor Binding and Pituitary Responsiveness in Estradiol-Primed Monkeys
Authors: Adams Thomas E. , Norman Reid L. , Spies Harold G.
Published: October 2006

Anterior pituitary tissue from ovariectomized cynomolgus macaques (
Macaca fascicularis
) contains a single class of high-affinity receptor for gonadotropin-releasing hormone (GnRH). Exogenous estradiol causes a twofold increase in the tissue concentration of GnRH receptor within 36 hours without affecting receptor affinity. Release of luteinizing hormone in response to exogenous GnRH is initially suppressed by estradiol, but pituitary responsiveness is restored within 36 hours of introduction of estradiol. The pituitary tissue concentration of GnRH receptor is positively correlated with estradiol-induced release of luteinizing hormone only during the phase of potentiated response, an indication that although the augmentation of responsiveness by estradiol may reflect an increased GnRH receptor concentration, the suppression of the luteinizing hormone response by estradiol probably reflects estradiol actions at loci other than the pituitary GnRH receptor.
Expression of Bovine Leukemia Virus Genome Is Blocked by a Nonimmunoglobulin Protein in Plasma from Infected Cattle
Authors: Gupta P. , Ferrer J. F.
Published: October 2006

Plasma of cattle infected with bovine leukemia virus contains a soluble factor that blocks the expression of the viral genome in cultured lymphocytes. The blocking factor is not present in plasma of bovine leukemia virus-free cattle or of cattle infected with common bovine viruses. Blocking of bovine leukemia virus expression by the plasma factor is reversible, and seems to be mediated by a nonimmunoglobulin protein molecule.
Saxitoxin Binding Sites in Frog Myocardial Cytosol
Authors: Doyle D. D. , Wong M. , Tanaka J. , Barr L.
Published: October 2006

Cytosolic fractions of frog heart homogenates contain large amounts of a soluble, large molecular weight protein that binds the specific neurotoxin saxitoxin with the same high affinity as does the plasma membrane. Another neurotoxin, tetrodotoxin, which ordinarily is competitive with saxitoxin, does not displace saxitoxin from the cytosolic sites or from plasma membrane-enriched vesicular fractions even when its concentration exceeds that of saxitoxin by a factor of 1000. Thus, cytosolic sites are similar to membrane sites in this respect. The vesicular fraction accounts quantitatively for the amount of saxitoxin bound by whole ventricles, so that no appreciable losses seem to occur. Therefore, the cytosolic site probably is a membrane site precursor, although other possibilities cannot be ruled out. In any case, the occurrence of a soluble molecule closely related to the sodium channel provides opportunities for further study of the structure of the sodium channel.
α
2
-Adrenoceptor-Mediated Hyperpolarization of Locus Coeruleus Neurons: Intracellular Studies in Vivo
Authors: Aghajanian G. K. , VanderMaelen C. P.
Published: October 2006

Intracellular recordings in vivo from noradrenergic neurons of the rat locus coeruleus showed that membrane potential was hyperpolarized by the administration of clonidine (an α
2
-adrenoceptor agonist) or after a burst of spikes evoked by intracellular pulses; both types of hyperpolarization were associated with a decrease in membrane input resistance, and both could be blocked by the α
2
-adrenoceptor antagonist piperoxane. These results suggest that a hyperpolarization of membrane potential mediated by an α
2
-adrenoceptor underlies both clonidine- and activation-induced inhibition of locus coeruleus cell firing.
Extracellular Potassium Ions Mediate Specific Neuronal Interaction
Authors: Yarom Y. , Spira M. E.
Published: October 2006

The giant interneurons from the nerve system of the cockroach
Periplaneta americana
exhibit a peculiar reciprocal synaptic interaction. The synaptic potentials are not blocked by addition of 5 millimolar cobalt chloride and have an extrapolated reversal potential close to 0 millivolt. Hyperpolarizing current injected into one cell does not spread to the other. Intracellular injection of tetraethylammonium ions into one giant interneuron increases the duration of the action potential of the injected cell to 30 milliseconds and reduces the rise time and amplitude of the postsynaptic response recorded in the other giant interneuron. These results indicate that the interaction between the interneurons is not mediated by conventional chemical or electrotonic synapses. All evidence points to generation of the potentials by localized increases in extracellular potassium concentrations as a consequence of firing of one neuron.
Spinal Sympathetic Neurons: Possible Sites of Opiate-Withdrawal Suppression by Clonidine
Authors: Franz Donald N. , Hare Bradford D. , McCloskey Kevin L.
Published: October 2006

Morphine, methadone, meperidine, fentanyl, and clonidine rapidly depressed transmission through sympathetic preganglionic neurons in cats with the spinal cord transected. Naloxone promptly antagonized this effect of the opiates but not that of clonidine which was reversed by α2-adrenergic receptor antagonists. The independent depression of preganglionic neurons by clonidine may contribute to the ability of this drug to depress the symptoms of opiate withdrawal that are characterized by sympathetic hyperactivity.