bluuebunny/crossref_metadata_2025 huggingface dataset:
Selective Inhibition of Glycoprotein and Membrane Protein of Vesicular Stomatitis Virus from Interferon-Treated Cells
Authors: Maheshwari Radha K. , Jay Francis T. , Friedman Robert M.
Published: October 2006

A 200-fold inhibition in the titer of infectious vesicular stomatitis virus (VSV) was produced in cultures of Ly cells treated with 30 reference units of interferon per milliliter. Virus particle production, as measured by VSV particle-associated transcriptase, or nucleocapsid protein was inhibited by a maximum of tenfold. The glycoprotein and membrane protein content was reduced in VSV derived from interferon-treated cells. Thus interferon-treated cells may have produced VSV particles with low infectivity, which may be related to the reduced amount of glycoprotein incorporated into such particles. These findings resemble those reported in interferon-treated cells infected with murine leukemia viruses.
Opiate Analgesia: Evidence for Mediation by a Subpopulation of Opiate Receptors
Authors: Pasternak Gavril W. , Childers Stephen R. , Snyder Solomon H.
Published: October 2006

Naloxazone, a hydrazone derivative of the opiate antagonist naloxone, has a high affinity for opiate receptor binding sites. Naloxazone injections reduce opiate receptor binding to extensively washed mouse brain membranes for more than 24 hours, suggesting that the effect is irreversible. High-affinity binding sites are abolished by this treatment, whereas low-affinity sites are unaffected. Naloxazone treatment blocks the analgesic effects of morphine for at least 24 hours but does not prevent death from high doses of morphine. Thus analgesic but nonlethal opiate effects may be mediated by the high-affinity subpopulation of opiate receptors.
Single-Shot Channel Activation Accounts for Duration of Inhibitory Postsynaptic Potentials in a Central Neuron
Authors: Faber Donald S. , Korn Henri
Published: October 2006

In the goldfish Mauthner cell, inhibitory postsynaptic currents evoked by intracellular stimulation of presynaptic neurons decay exponentially, with a mean time constant of 6.65 milliseconds. Analysis of membrane conductance fluctuations induced by iontophoresis of glycine and γ-aminobutyric acid indicates a mean inhibitory channel lifetime of 7.15 milliseconds. The results thus suggest that the relaxation kinetics of activated inhibitory channels are rate-limiting during decay of the inhibitory postsynaptic current.
Electrical Stimulation of the Midbrain Mediates Metastatic Tumor Growth
Authors: Simon Richard H. , Lovett Edmund J. , Tomaszek David , Lundy Joel
Published: October 2006

Pulmonary metastases were counted 10 days after female rats received tail-vein injections of Walker-256 carcinosarcoma cells. Previous observations that halothane anesthesia plus hind-limb amputation increases the number of metastases were confirmed. Amputation under the analgesia of electrical stimulation of the midbrain was found to increase metastatic activity. However, the stimulus-produced analgesia alone also increased the number of metastases. Systemically administered naloxone blocked the analgesic effect of midbrain stimulation but did not block the increase in the number of pulmonary metastases.
Electroconvulsive Shock: Progressive Dopamine Autoreceptor Subsensitivity Independent of Repeated Treatment
Authors: Chiodo Louis A. , Antelman Seymour M.
Published: October 2006

Repeated electroconvulsive shock, applied to rats, induces a subsensitivity of dopamine autoreceptors located in the substantia nigra as indexed by single-unit electrophysiological techniques. This reduced sensitivity is time-dependent, since effects similar to those seen with repeated treatment were also observed when single electroconvulsive shock was followed by an appropriate treatment-free interval. These data, coupled with identical results after the repeated administration of tricyclic antidepressants, raise the possibility that a reduction of dopamine autoreceptor sensitivity could underlie both electroconvulsive shock and pharmacological treatment of depression.
Vasoactive Intestinal Peptide: A Possible Transmitter of Nonadrenergic Relaxation of Guinea Pig Airways
Authors: Matsuzaki Yoshikazu , Hamasaki Yuhei , Said Sami I.
Published: October 2006

Vasoactive intestinal peptide, a smooth-muscle relaxant neuropeptide with neurotransmitter properties, was released during electrical field stimulation of guinea pig trachea. The amount released correlated with the degree of relaxation, and the release was blocked by tetrodotoxin. Prior incubation of the trachea with antiserum to vasoactive intestinal peptide reduced the relaxation. Thus vasoactive intestinal peptide may mediate the nonadrenergic relaxation of tracheal smooth muscle.
Plasmid DNA in
Treponema pallidum
(Nichols): Potential for Antibiotic Resistance by Syphilis Bacteria
Authors: Norgard Michael V. , Miller James N.
Published: October 2006

A plasmid DNA structure (approximate molecular weight = 7.5 × 10
6
) was identified in the human pathogen
Treponema pallidum
(Nichols). The inability to isolate this plasmid from rabbit host tissue and the total lack of DNA homology of the plasmid with rabbit DNA has confirmed its
Treponema pallidum
origin. The observation documents a newly recognized and potentially significant genetic capability for
Treponema pallidum
.
Opioid Inhibition of Dopamine Release from Nervous Tissue ofMytilus edulisandOctopus bimaculatus
Authors: Stefano George B. , Hall Beverly , Makman Maynard H. , Dvorkin Bernyce
Published: October 2006

Morphine and D-Ala2-Met-enkephalin as well as other opioids suppress potassium-stimulated release of3H-labeled dopamine from nervous tissue of two marine invertebrates,Mytilus edulisandOctopus bimaculatus. Naloxone reverses the inhibitory effects in both species. Potassium-stimulated release of3H-labeled serotonin is not altered by opioids. It is postulated that opiate receptors and their endogenous effectors play a prominent role in regulation of transmitter release in invertebrates.
Sodium Pump in Skeletal Muscle: Central Nervous System-Induced Suppression by α-Adrenoreceptors
Authors: Akaike Norio
Published: October 2006

The central nervous system regulates active sodium and potassium transport in rat skeletal muscle during hypokalemia. This regulation is achieved by the apparent release of catecholamines onto muscle following nerve activity. This effect can be prevented by treatment with agents that block the α-adrenoreceptor.
Fc and C3b Receptors on Pulmonary Endothelial Cells: Induction by Injury
Authors: Ryan Una S. , Schultz Duane R. , Ryan James W.
Published: October 2006

Receptors for the activated third component of complement and for the Fc portion of immunoglobulin G are not expressed by apparently normal bovine pulmonary endothelial cells, but are expressed when the cells are exposed to white cell lysates or are infected with influenza or cytomegalovirus. The unmasking of these latent receptors may contribute to the pulmonary inflammatory response characteristic of, for example, anaphylaxis and to those lung diseases characterized by the deposition of immune complexes.
Quantitative Autoradiography of [
3
H]Muscimol Binding in Rat Brain
Authors: Penney John B. , Pan Helen S. , Young Anne B. , Frey Kirk A. , Dauth George W.
Published: October 2006

A simple quantitative autoradiographic technique for the study of neurotransmitter receptors that includes the use of a tritium-sensitive film permits saturation, kinetic, and competition studies of brain samples as small as 0.01 cubic millimeter. This technique was used to study [
3
H]muscimol binding in rat brain. Unilateral γ-aminobutyric acid receptor supersensitivity was observed in the substantia nigra pars reticulata after production of localized lesions of the ipsilateral corpus striatum.
Isolation of Human Oncogene Sequences (v-
fes
Homolog) from a Cosmid Library
Authors: Groffen John , Heisterkamp Nora , Grosveld Frank , Van de Ven Wim , Stephenson
Published: October 2006

To define the human homolog (or homologs) of transforming sequences (v-
fes
gene) common to Gardner (GA) and Snyder Theilen (ST) isolates of feline sarcoma virus (FeSV), a representative library of human lung carcinoma DNA in a cosmid vector system was constructed. Three cosmid clones were isolated containing GA/ST FeSV v-
fes
homologous cellular sequences, within 32- to 42-kilobase cellular inserts representing 56 kilobases of contiguous human cellular DNA. Sequences both homologous to, and colinear with, GA or ST FeSV v-
fes
are distributed discontinuously over a region of up to 9.5 kilobases and contain a minimum of three regions of nonhomology representing probable introns. A thymidine kinase selection system was used to show that, upon transfection to RAT-2 cells, the human c-
fes
sequence lacked detectable transforming activity.
Interaction of Convulsive Ligands with Benzodiazepine Receptors
Authors: Braestrup C. , Schmiechen R. , Neef G. , Nielsen M. , Petersen E. N.
Published: October 2006

The γ-aminobutyric acid (GABA)-benzodiazepine receptor complex, which is composed of distinct proteins embedded in the neuronal plasma membrane, is important for several effects of benzodiazepines, including protection afforded against convulsions. During structural modification of ethyl β-carboline-3-carboxylate an agent was discovered which has high affinity for brain benzodiazepine receptors but which is a potent convulsant. Also in contrast to benzodiazepines, this type of benzodiazepine receptor ligand favors benzodiazepine receptors in the non-GABA-stimulated conformation, which may explain the convulsive properties.
Micromolar Affinity Benzodiazepine Receptors: Identification and Characterization in Central Nervous System
Authors: Bowling Allen C. , DeLorenzo Robert J.
Published: October 2006

Receptors that selectively bind micromolar concentrations of benzodiazepines are present in rat brain membrane. These micromolar receptors exhibit saturable, stereospecific binding, and the potency of benzodiazepine binding to these receptors is correlated with the ability of the benzodiazepines to inhibit maximum electric shock-induced convulsions. Benzodiazepine receptors with nanomolar affinity differ from the micromolar receptors in their binding, kinetic, and pharmacologic characteristics. The micromolar receptors also bind phenytoin, a non-benzodiazepine anticonvulsant. These results provide evidence for a distinct class of clinically relevant benzodiazepine receptors that may regulate neuronal excitability and anticonvulsant activity.
Phagocyte Impotence Caused by an Invasive Bacterial Adenylate Cyclase
Authors: Confer Dennis L. , Eaton John W.
Published: October 2006

For unknown reasons, humans infected with the bacterium
Bordetella pertussis
are exceptionally vulnerable to secondary infections.
Bordetella
species elaborate a soluble, heat-stable, and highly active adenylate cyclase. This enzyme is internalized by phagocytic cells and catalyzes the unregulated formation of adenosine 3′,5′-monophosphate (cyclic AMP), thereby disrupting normal cellular function. This unusual phenomenon may explain
Bordetella
-induced aphylaxis and may prove to be useful for investigating a variety of cyclic AMP-governed processes.
Role of Serotonergic Input in the Regulation of the β-Adrenergic Receptor-Coupled Adenylate Cyclase System
Authors: Janowsky Aaron , Okada Fumihiko , Manier D. Hal , Applegate Craig D. , Sulser Fridolin , Steranka Larry R.
Published: October 2006

The action of desipramine on the norepinephrine-sensitive adenylate cyclase system and the density of β-adrenergic receptors in rat cortex was studied after selective lesioning of serotonergic neurons with 5,7-dihydroxytryptamine. In animals with lesions desipramine failed to reduce the density of β-adrenoceptors but decreased the response of adenosine 3′,5′-monophosphate to isoproterenol and norepinephrine to the same degree as in animals without lesions. The results demonstrate a functional linkage between serotonergic and noradrenergic systems in the rat cortex, with β-adrenergic receptors and neurohormonal sensitivity of the adenosine 3′,5′-monophosphate-generating system being under separate regulatory control.
Recombination During Gene Transfer into Mouse Cells Can Restore the Function of Deleted Genes
Authors: Small Judy , Scangos George
Published: October 2006

Two plasmids containing nonoverlapping deletions of the herpes simplex virus thymidine kinase gene were introduced into thymidine kinase-deficient mouse L cells by DNA-mediated gene transfer. Thymidine kinase-producing transformants were generated by a mixture of the two plasmids at a frequency significantly greater than that generated by either plasmid alone. Southern blot analyses demonstrated that functional thymidine kinase genes were generated by homologous recombination between the two deletion mutants.
Monoclonal Antibodies for Diagnosis of Infectious Diseases in Humans
Authors: Nowinski Robert C. , Tam Milton R. , Goldstein Lynn C. , Stong Linda , Kuo Cho-Chou , Corey Lawrence , Stamm Walter E. , Handsfield H. Hunter , Knapp Joan S. , Holmes King K.
Published: October 2006

Monoclonal antibody techniques are now widely practiced. and antibodies of diagnostic potential have been prepared in research laboratories against a battery of viruses, bacteria, fungi, and parasites. In this article the diagnostic utility of monoclonal antibodies for gonococcal, chlamydial, and herpesvirus infections is described. With immunofluorescence being used as an assay system, the antibodies demonstrated sensitivities of 94 to 99 percent for culture confirmation and 85 to 90 percent for direct diagnosis of specimens smeared on microscope slides. Since the direct diagnostic tests only required 15 to 20 minutes to perform, they represented a major advance in the diagnosis of infections which previously required 3 to 6 days to accomplish. It is anticipated that in the next decade an entirely new spectrum of antibody-based diagnostics will be developed, allowing the rapid, precise, and semiautomated diagnosis of many infectious diseases.
Adenylate Cyclase Activation Shifts the Phase of a Circadian Pacemaker
Authors: Eskin Arnold , Takahashi Joseph S.
Published: October 2006

Forskolin, a highly specific activator of adenylate cyclase, produced both delay and advance phase shifts of the circadian rhythm recorded from the isolated eye of the marine mollusk
Aplysia
. The phase dependence of the response to forskolin was identical to that with serotonin, which also stimulates adenylate cyclase in the eye. The ability of agents to activate adenylate cyclase in homogenates was correlated with their ability to shift the phase of the circadian oscillator. These results along with earlier findings show that adenosine 3′,5′-monophosphate mediates the effect of serotonin on the rhythm and regulates the phase of the circadian pacemaker in the eye of
Aplysia
.
BK Viral Enhancer Element and a Human Cellular Homolog
Authors: Rosenthal Nadia , Kress Michel , Gruss Peter , Khoury George
Published: October 2006

Comparison of two closely related primate papovaviruses, simian virus 40 (SV40) and human BK virus (BKV), reveals that the only region of extensive divergence, the tandem sequences adjacent to the origins of DNA replication, is responsible in SV40 for enhancing early gene expression. This study demonstrates a similar enhancer function for the analogous repeated region in BKV. The dissimilarity in sequence of the BKV and SV40 enhancer elements suggests that they may have been acquired since SV40 and BKV diverged. A locus cloned from the human genome homologous to the BKV tandem repeats has been shown to function as low level enhancer element in mammalian cells. These data support the hypothesis that viral enhancer sequences may be evolutionarily related to host cell sequences.
Transformation and Cytopathogenic Effect in an Immune Human T-Cell Clone Infected by HTLV-I
Authors: Mitsuya Hiroaki , Guo Hong-Guang , Megson Mary , Trainor Cecelia , Reitz Marvin S. , Broder Samuel
Published: October 2006

Human T-cell leukemia-lymphoma virus (HTLV) is a human C-type retrovirus that can transform T lymphocytes in vitro and is associated with certain T-cell neoplasms. Recent data suggest that, in the United States, patients with acquired immunodeficiency syndrome (AIDS), homosexual men with lymphadenopathy, and hemophiliacs have had significant exposure rates to HTLV, whereas matched and unmatched control American subjects have rarely been exposed to this agent. In the present experiments, T cells specifically reactive against HTLV were propagated from a patient whose HTLV-bearing lymphoma was in remission. The T cells were cloned in the presence of the virus and an HTLV-specific cytotoxic T-cell clone was isolated. This clone was infected and transformed by the virus, with one copy of an HTLV-I provirus being integrated into the genome. This T-cell clone did not exhibit the normal dependence on T-cell growth factor (interleukin-2) and proliferated spontaneously in vitro. Exposure of the clone to HTLV-bearing, autologous tumor cells specifically inhibited its proliferation and resulted in its death. These results may have implications for HTLV-associated inhibition of T-cell responses.
Schwann Cell Galactocerebroside Induced by Derivatives of Adenosine 3′,5′-Monophosphate
Authors: Sobue Gen , Pleasure David
Published: October 2006

Indirect immunofluorescence was used to show the presence of galactocerebroside (galC), a lipid found in myelin, on the surface of about half of the Schwann cells isolated from neonatal rat sciatic nerves and cultured for 1 day without neurons. By day 4 in vitro, the Schwann cells had all lost their surface galC. Three days after beginning treatment with 10
-3
molar 8-bromo-adenosine 3′,5′-monophosphate (8-bromo cyclic AMP) or
N
6
,
O
2′
-dibutyryl adenosine 3′,5′-monophosphate (dibutyryl cyclic AMP), galC reappeared on the Schwann cells, and 2 days later 48 percent of the cultured Schwann cells showed surface galC. Tritium from tritiated D-galactose was incorporated into galC by the 8-bromo cyclic AMP- and dibutyryl cyclic AMP-treated cultures at a rate 15 times the control rate.
Sodium-Coupled Sugar Transport: Effects on Intracellular Sodium Activities and Sodium-Pump Activity
Authors: Hudson Randall L. , Schultz Stanley G.
Published: October 2006

Intracellular sodium activities, (Na)
c
, were determined in Necturus small intestine before and after addition of galactose to the mucosal bathing solution. In the absence of galactose, (Na)
c
averaged 12 millimoles per liter. Within 2 minutes after the addition of galactose to the mucosal solution, (Na)
c
increased to a mean value of 20 millimoles per liter and then declined, in parallel with an increase in transcellular sodium transport, to a value that did not differ significantly from that observed in the absence of the sugar. The final steady state in the presence of galactose was characterized by a three- to fourfold increase in the rate of transcellular Na
+
transport in the absence of a significant increase in (Na)
c
. Thus, the increase in steady-state basolateral pump activity cannot be attributed to an increase in the intracellular sodium transport pool.
Reinitiation of Growth in Senescent Mouse Mammary Epithelium in Response to Cholera Toxin
Authors: Daniel Charles W. , Silberstein Gary B. , Strickland Phyllis
Published: October 2006

Several lines of mouse mammary tissue that had been serially transplanted until mitotic senescence was reached were exposed in vivo to plastic implants that slowly released cholera toxin. Gland tissue surrounding the implants displayed new end buds, indicating reinitiation of growth and morphogenesis. The ability of cholera toxin, which elevates intracellular adenosine 3′,5′-monophosphate, to temporarily reverse the senescent phenotype suggests that this mitotic dysfunction results not from generalized cellular deterioration but from specific changes in cell regulation.
Decreased Neuronal Inhibition in Vitro After Long-Tterm Administration of Ethanol
Authors: Durand D. , Carlen P. L.
Published: October 2006

The pathophysiology of brain dysfunction was studied with an animal model of chronic alcoholism. Rats were fed a liquid diet with or without ethanol for 20 weeks and then the diet without ethanol for three more weeks. Hippocampal slices were prepared and intracellular recordings were obtained from dentate granule and CA1 cells. Significant depression of orthodromically elicited inhibitory postsynaptic potentials and postspike afterhyperpolarizations was observed in neurons from ethanol-exposed animals. No differences were observed in other active or passive membrane characteristics. These results suggest that a loss of neuronal inhibition could contribute to brain dysfunction in chronic alcoholism.
Corticotropin-Releasing Factor Receptors in Rat Forebrain: Autoradiographic Identification
Authors: De Souza Errol B. , Perrin Marilyn H. , Insel Thomas R. , Rivier Jean , Vale Wylie W. , Kuhar Michael J.
Published: October 2006

Corticotropin-releasing factor (CRF) receptors were identified in rat forebrain by autoradiography with an iodine-125-labeled analog of ovine CRF substituted with norleucine and tyrosine at amino acid residues 21 and 32, respectively. High-affinity receptors for CRF were found in discrete areas of rat forebrain, including laminae I and IV of the neocortex, the external layer of the median eminence, the lateral nucleus of the amygdala, and the striatum. These results are consistent with earlier findings on the immunohistochemical distribution of CRF and suggest that endogenous CRF has a physiological role in regulating activity of the central nervous system.
Antibodies to the Core Protein of Lymphadenopathy-Associated Virus (LAV) in Patients with AIDS
Authors: Kalyanaraman V. S. , Cabradilla C. D. , Getchell J. P. , Narayanan R. , Braff E. H. , Chermann J.-C. , Barré-Sinoussi F. , Montagnier L. , Spira T. J. , Kaplan J. , Fishbein D. , Jaffe H. W. , Curran J. W. , Francis D. P.
Published: October 2006

Lymphadenopathy-associated virus (LAV), a human T-lymphotrophic retrovirus isolated from a homosexual man with lymphadenopathy, has been causally associated with acquired immunodeficiency syndrome (AIDS). A sensitive and specific radioimmunoprecipitation test was developed for the detection of antibodies to the major core protein of LAV, p25 (molecular weight 25,000). Antibody to LAV p25 was found in the serum of 51 of 125 AIDS patients, 81 of 113 patients with lymphadenopathy syndrome, 0 of 70 workers at the Centers for Disease Control (some of whom had handled specimens from AIDS patients), and 0 of 189 random blood donors. Of a group of 100 homosexual men from San Francisco whose serum was obtained in 1978, only one had antibody to LAV p25; in contrast, of a group of 50 homosexual men in the same community whose serum was obtained in 1984, 12 had antibodies to LAV p25.
Patient with 13 Chromosome Deletion: Evidence That the Retinoblastoma Gene Is a Recessive Cancer Gene
Authors: Benedict William F. , Murphree A. Linn , Banerjee Ashutosh , Spina Celsa A. , Sparkes Maryellen C. , Sparkes Robert S.
Published: October 2006

Although a constitutional chromosomal deletion including 13q14 has been found to date in all retinoblastoma patients whose esterase D activity is 50 percent of normal, one female patient has been found who has 50 percent esterase D activity in all normal cells examined but no deletion of 13q14 at the 550-band level. Therefore, she has the smallest constitutional chromosomal deletion within 13q14 that is associated with susceptibility to retinoblastoma. Two stem lines were identified in a retinoblastoma from this patient, and each one had a missing 13 chromosome. No detectable esterase D activity was found in the tumor, indicating that the normal nondeleted 13 chromosome was lost in both stem lines. Thus the data from this patient not only show that there is a total loss of genetic information at the location of the retinoblastoma gene within the tumor, but also imply that recessive genes may play an important role in the development of certain human tumors including retinoblastoma.
The Chromosomal Basis of Human Neoplasia
Authors: Yunis Jorge J.
Published: October 2006

High-resolution banding techniques for the study of human chromosomes have revealed that the malignant cells of most tumors analyzed have characteristic chromosomal defects. Translocations of the same chromosome segments with precise breakpoints occur in many leukemias and lymphomas, and a specific chromosome band is deleted in several carcinomas. Trisomy, or the occurrence of a particular chromosome in triplicate, is the only abnormality observed in a few neoplasias. It is proposed that chromosomal rearrangements play a central role in human neoplasia and may exert their effects through related genomic mechanisms. Thus, a translocation could serve to place an oncogene next to an activating DNA sequence, a deletion to eliminate an oncogene repressor, and trisomy to carry extra gene dosage.
5-Thio-D-Glucose Selectively Potentiates Hyperthermic Killing of Hypoxic Tumor Cells
Authors: Kim Jae Ho , Kim Sang Hie , Hahn Eric W. , Song C. W.
Published: October 2006

To investigate the mechanisms by which heat affects cancer cells, we used 5-thio-D-glucose, an inhibitor of glycolysis in HeLa S-3 cells, under aerobic and hypoxic conditions at temperatures ranging from 37° to 43°C. Drug alone or heat alone killed a minimum number of cells under aerobic or hypoxic conditions. Exposure to drug and hyperthermia selectively increased the number of cells killed under hypoxic conditions at temperatures as low as 40.5°C but had little effect on cells incubated under aerobic conditions. These results suggest that the glycolytic pathway is a primary site of hyperthermic damage leading to cell death.
Improving Cognitive Ability in Chronically Deprived Children
Authors: McKay Harrison , Sinisterra Leonardo , McKay Arlene , Gomez Hernando , Lloreda Pascuala
Published: October 2006

Beginning at different ages in their preschool years, groups of chronically undernourished children from Colombian families of low socioeconomic status participated in a program of treatment combining nutritional, health care, and educational features. By school age the gap in cognitive ability between the treated children and a group of privileged children in the same city had narrowed, the effect being greater the younger the children were when they entered the treatment program. The gains were still evident at the end of the first grade in primary school, a year after the experiment had ended.
Psychophysical Functions for Perceived and Remembered Size
Authors: Moyer Robert S. , Bradley Drake R. , Sorensen Mark H. , Whiting John C. , Mansfield David P.
Published: October 2006

Separate groups of people estimated the sizes of perceived or of remembered objects. In three independent experiments, both sets of data were well fit by power functions, and the exponent was reliably smaller for remembered than for perceived size.
Soluble Lectins: A New Class of Extracellular Proteins
Authors: Barondes Samuel H.
Published: October 2006

Soluble lectins of cellular slime molds and vertebrates are present at extracellular sites in the developing or adult tissues that make them. Some lectins are concentrated around cell groups, as in extracellular matrix or elastic fibers. Others are at the interface between cells and the external environment, as in mucin or slime. Specific glycoproteins, proteoglycans, or polysaccharides that bind these endogenous lectins may also be present at these sites. Interactions between the lectins and glycoconjugates appear to play a role in shaping extracellular environments.
Effects of Cyclosporine Immunosuppression in Insulin-Dependent Diabetes Mellitus of Recent Onset
Authors: Stiller C. R. , Dupré J. , Gent M. , Jenner M. R. , Keown P. A. , Laupacis A. , Martell R. , Rodger N. W. , von Graffenried B. , Wolfe B. M. J.
Published: October 2006

Type I diabetes may be an autoimmune disorder, although the evidence is largely circumstantial. The natural history of the disease after diagnosis includes partial remission in most patients, but only about 3 percent achieve transient insulin independence. β Cell function, as indicated by the plasma concentration of C-peptide, is lost over 6 to 30 months and islet cell antibodies disappeared over 1 to 2 years. This article describes a pilot study in which 41 patients were treated with the immunosuppressive agent cyclosporine for 2 to 12 months. Of 30 patients treated within 6 weeks of diagnosis, 16 became insulin independent with concentrations of plasma C-peptide in the normal range and decreasing titers of islet cell antibodies. Of 11 patients who entered the study 8 to 44 weeks after diagnosis, two achieved this state. These results indicate that a controlled trial of the effects of cyclosporine in type I diabetes should be conducted.
Structure and Expression of a Complementary DNA for the Nuclear Coded Precursor of Human Mitochondrial Ornithine Transcarbamylase
Authors: Horwich Arthur L. , Fenton Wayne A. , Williams Kenneth R. , Kalousek Frantisek , Kraus Jan P. , Doolittle Russell F. , Konigsberg William , Rosenberg Leon E.
Published: October 2006

Most mitochondrial proteins are encoded in the nucleus and are translated on free cytoplasmic ribosomes as larger precursors containing amino-terminal "leader" sequences, which are removed after the precursors are taken up by mitochondria. We have deduced the complete primary structure of the precursor of a human mitochondrial matrix enzyme, ornithine transcarbamylase (OTC), from the nucleotide sequence of cloned complementary DNA. The amino-terminal leader peptide of OTC is 32 amino acids in length and contains four arginines but no acidic residues. Cleavage of the leader peptide from the "mature" protein occurs between glutamine and asparagine residues. The sequence of mature human OTC resembles that of the subunits of both OTC and aspartate transcarbamylase from Escherichia coli. The biological activity of the cloned OTC complementary DNA was tested by joining it with SV40 (an animal virus) regulatory elements and transfecting cultured HeLa cells, which do not normally express OTC. Both the precursor and mature forms of the OTC subunit were identified; in stable transformants, enzymatic activity was also detected.
Autoantibodies to a 64-Kilodalton Islet Cell Protein Precede the Onset of Spontaneous Diabetes in the BB Rat
Authors: Baekkeskov Steinunn , Dyrberg Thomas , Lernmark Åke
Published: October 2006

Spontaneous insulin-dependent diabetes mellitus (IDDM) in the BB rat is associated with the presence of antibodies to a 64-kilodalton rat islet cell protein. These protein antibodies appeared in young animals and remained for as long as 8 weeks before the clinical onset of IDDM. Antibodies to a 64-kilodalton human islet cell protein were found to be associated with human IDDM. Detection of the antibodies may therefore be used to predict an early immune reaction against pancreatic B cells.
1,25-Dihydroxyvitamin D
3
: a Novel Immunoregulatory Hormone
Authors: Tsoukas Constantine D. , Provvedini Diego M. , Manolagas Stavros C.
Published: October 2006

The hormonal form of vitamin D
3
, 1,25-dihydroxyvitamin D
3
[1,25(OH)
2
D
3
], at picomolar concentrations, inhibited the growth-promoting lymphokine interleukin-2, which is produced by human T lymphocytes activated in vitro by the mitogen phytohemagglutinin. Other metabolites of vitamin D
3
were less effective than 1,25(OH)
2
D
3
in suppressing interleukin-2; their order of potency corresponded to their respective affinity for the 1,25(OH)
2
D
3
receptor, suggesting that the effect on interleukin-2 was mediated by this specific receptor. The proliferation of mitogen-activated lymphocytes was also inhibited by 1,25(OH)
2
D
3
. This effect of the hormone became more pronounced at later stages of the culture. These findings demonstrate that 1,25(OH)
2
D
3
is an immunoregulatory hormone.
Ah Locus: Genetic Differences in Susceptibility to Cataracts Induced by Acetaminophen
Authors: Shichi Hitoshi , Gaasterland Douglas E. , Jensen Nancy M. , Nebert Daniel W.
Published: October 2006

The Ah
b
/Ah
b
homozygous and the Ah
b
/Ah
d
heterozygous inbred mouse strains from the (C57BL/6)(DBA/2)F
1
× DBA/2 backcross are genetically responsive to 3-methylcholanthrene. They both also develop, within 6 hours after a large intraperitoneal dose of acetaminophen, an irreversible opacity in the anterior portion of the lens. Such cataract formation does not occur in similarly treated nonresponsive inbred strains or nonresponsive Ah
d
/Ah
d
individuals from the same backcross. Differences in acetaminophen metabolism and toxicity are associated with the Ah locus in the mouse, and differences in heritability at the Ah locus exist in the human. Our ophthalmologic findings may be important clinically to certain patients receiving either a single large overdose of this drug or high doses over a long period.
Fidelity of Mammalian DNA Polymerases
Authors: Kunkel Thomas A. , Loeb Lawrence A.
Published: October 2006

The fidelity of copying natural DNA in vitro with each of the three classes of eukaryotic DNA polymerases has been determined. DNA polymerases-β and -γ are highly inaccurate, catalyzing noncomplementary single-base substitution at a frequency between 1/3000 and 1/8000. DNA polymerase-α is substantially more accurate, with an error rate of 1/30,000. When the error rates of these DNA polymerases are considered in the context of the accuracy of DNA replicative processes in vivo, it seems likely that other factors must exist in mammalian cells which are involved in the accurate replication and maintenance of the genetic information.
Alzheimer's Disease: Cell-Specific Pathology Isolates the Hippocampal Formation
Authors: Hyman Bradley T. , Van Hoesen Gary W. , Damasio Antonio R. , Barnes Clifford L.
Published: October 2006

Examination of temporal lobe structures from Alzheimer patients reveals a specific cellular pattern of pathology of the subiculum of the hippocampal formation and layers II and IV of the entorhinal cortex. The affected cells are precisely those that interconnect the hippocampal formation with the association cortices, basal forebrain, thalamus, and hypothalamus, structures crucial to memory. This focal pattern of pathology isolates the hippocampal formation from much of its input and output and probably contributes to the memory disorder in Alzheimer patients.
Inhibitors of Lysosomal Enzymes: Accumulation of Lipofuscin-Like Dense Bodies in the Brain
Authors: Ivy G. O. , Schottler F. , Wenzel J. , Baudry M. , Lynch G.
Published: October 2006

Injections of leupeptin (a thiol proteinase inhibitor) or chloroquine (a general lysosomal enzyme inhibitor) into the brains of young rats induced the formation of lysosome-associated granular aggregates (dense bodies) which closely resembled the ceroid-lipofuscin that accumulates in certain disease states and during aging. The dense material increased in a dose- and time-dependent fashion and was differentially distributed across brain regions and cell types. These observations provide clues to the origins of ceroid-lipofuscin and suggest means for studying the consequences of its accumulation.
Smell Identification Ability: Changes with Age
Authors: Doty Richard L. , Shaman Paul , Applebaum Steven L. , Giberson Ronita , Siksorski Lenore , Rosenberg Lysa
Published: October 2006

Smell identification ability was measured in 1955 persons ranging in age from 5 to 99 years. On the average, women outperformed men at all ages, and nonsmokers outperformed smokers. Peak performance occurred in the third through fifth decades and declined markedly after the seventh. More than half of those 65 to 80 years old evidenced major olfactory impairment. After 80 years, more than three-quarters evidenced major impairment. Given these findings, it is not surprising that many elderly persons complain that food lacks flavor and that the elderly account for a disproportionate number of accidental gas poisoning cases each year.
Vasopressin Injected into the Hypothalamus Triggers a Stereotypic Behavior in Golden Hamsters
Authors: Ferris C. F. , Albers H. E. , Wesolowski S. M. , Goldman B. D. , Luman S. E.
Published: October 2006

Microinjection of arginine vasopressin into the medial preoptic area of the hypothalamus of male and female golden hamsters triggered a complex, stereotypic behavior—flank marking—a type of scent marking used in olfactory communication. The flank marking was not elicited by saline, oxytocin, neurotensin, or angiotensin II. Vasopressin was ineffective when injected into other areas of the hypothalamus or into the lateral cerebroventricle.
Tumor-Derived Growth Factor Increases Bone Resorption in a Tumor Associated with Humoral Hypercalcemia of Malignancy
Authors: Ibbotson K. J. , D'Souza S. M. , Ng K. W. , Osborne C. K. , Niall M. , Martin T. J. , Mundy G. R.
Published: October 2006

Evidence is presented that a tumor-derived transforming growth factor is responsible for stimulating bone resorption and causing hypercalcemia in an animal tumor model of the hypercalcemia of malignancy. Both conditioned medium harvested from cultured tumor cells and tumor extracts of the transplantable rat Leydig cell tumor associated with hypercalcemia contained a macromolecular bone resorbing factor with the chemical characteristics of a tumor-derived transforming growth factor.
Molecular Cloning of the Chromosomal Breakpoint of B-Cell Lymphomas and Leukemias with the t(11;14) Chromosome Translocation
Authors: Tsujimoto Yoshihide , Yunis Jorge , Onorato-Showe Louise , Erikson Jan , Nowell Peter C. , Croce Carlo M.
Published: October 2006

The chromosomal breakpoint of chronic lymphocytic leukemia (CLL) cells of the B-cell type carrying the translocated long arms of chromosomes 11 and 14 [t(11;14) (q13;q32)] was cloned. The breakpoint was found to be within the joining segment of the human heavy chain locus on the translocated long arm of chromosome 14. A probe that is specific for chromosome 11 and that maps immediately 5′ to the breakpoint on the 14q
+
chromosome was isolated. The probe detected a rearrangement of the homologous genomic DNA segment in the parental CLL cells and also in DNA from a diffuse large cell lymphoma with the t(11;14) translocation. This rearranged DNA segment was not present in Burkitt lymphoma cells with the t(8;14) translocation or in nonneoplastic human lymphoblastoid cells. The probe can thus be used to identify and characterize a gene located on band q13 of chromosome 11 that appears to be involved in the malignant transformation of human B cells carrying the t(11;14) translocation. This gene, named
bcl-1
, appears to be unrelated to any of the known retrovirus oncogenes described to date.
Intracellular Recordings from Cochlear Inner Hair Cells: Effects of Stimulation of the Crossed Olivocochlear Efferents
Authors: Brown M. Christian , Nuttall Alfred L. , Masta Robert I.
Published: October 2006

Intracellular recordings were obtained from inner hair cells located in the lower basal turn of the guinea pig cochlea. At low sound pressure levels the inner hair cells were highly frequency selective, producing receptor potentials only in response to sound frequencies between about 16 and 24 kilohertz. Electrical stimulation of efferent nerves in the crossed olivocochlear bundle markedly reduced these receptor potentials while causing little change in the resting membrane potential. At high sound levels, where cells responded to an increasingly wider range of sound frequencies, stimulation was less effective in reducing receptor potentials. Since the crossed olivocochlear bundle primarily innervates outer hair cells, these results support an outer hair cell contribution to the most sensitive response region of inner hair cells.
External Human Fertilization: An Evaluation of Policy
Authors: Grobstein Clifford , Flower Michael , Mendeloff John
Published: October 2006

In vitro fertilization, in its first 5 years of use, has met minimum standards for efficacy and safety, as judged by published clinical reports. It is becoming more widely available as an approach for overcoming sterility in married couples and appears also to be gaining social acceptance in that context. Several technical options presented by the procedure, particularly storage of frozen embryos and embryo transfers involving third-party contributions, are less fully evaluated clinically and raise social, ethical, and legal questions that go beyond the original medical model for therapeutic intervention. The clinical success of in vitro fertilization and the options it affords call for careful policy consideration. Estimates of costs and of potential demand for and supply of services are provided and the current status of relevant policy in the United States and abroad is discussed.
Fast Extracellular Calcium Transients: Involvement in Epileptic Processes
Authors: Pumain R. , Kurcewicz I. , Louvel J.
Published: October 2006

Improved liquid ion-exchanger microelectrodes made possible the observation of large, rapid decreases in the concentration of extracellular calcium ions during single epileptic spikes. Moreover, in definite cortical layers the decreases regularly started shortly before the onset of each epileptic spike. In view of the prominent role played by extracellular calcium ions in neuronal processes, including transmitter release and membrane excitability, these alterations probably exert a profound influence on the cellular events underlying epileptiform activity.
A Survey of Separative Techniques
Authors: Maugh Thomas H.
Published: October 2006

Separative science has recently undergone numerous advances. This article discusses many developments and trends in liquid, ion, gas, and countercurrent chromatography, field-flow fractionation, and electrophoresis.
Hypnotically Created Memory Among Highly Hypnotizable Subjects
Authors: Laurence Jean-Roch , Perry Campbell
Published: October 2006

A pseudomemory of having been awakened by some loud noises during a night of the previous week was suggested to 27 highly hypnotizable subjects during hypnosis. Posthypnotically, 13 of them stated that the suggested event had actually occurred. This finding has implications for the investigative use of hypnosis in a legal context.
Lateralization of Norepinephrine in Human Thalamus
Authors: Oke Arvin , Keller Richard , Mefford Ivan , Adams Ralph N.
Published: October 2006

Norepinephrine has a strongly lateralized distribution in the human thalamus. In the pulvinar region the left hemisphere is rich in norepinephrine, whereas in the somatosensory input area the right hemisphere has a higher concentration of this catecholamine. Such naturally occurring left-right differences in concentration of a neurotransmitter represent a new aspect of hemispheric specialization.
Statistical Problems in ESP Research
Authors: Diaconis Persi
Published: October 2006

In search of repeatable ESP experiments, modern investigators are using more complex targets, richer and freer responses, feedback, and more naturalistic conditions. This makes tractable statistical models less applicable. Moreover, controls often are so loose that no valid statistical analysis is possible. Some common problems are multiple end points, subject cheating, and unconscious sensory cueing. Unfortunately, such problems are hard to recognize from published records of the experiments in which they occur; rather, these problems are often uncovered by reports of independent skilled observers who were present during the experiment. This suggests that magicians and psychologists be regularly used as observers. New statistical ideas have been developed for some of the new experiments. For example, many modern ESP studies provide subjects with feedback—partial information about previous guesses—to reward the subjects for correct guesses in hope of inducing ESP learning. Some feedback experiments can be analyzed with the use of skill-scoring, a statistical procedure that depends on the information available and the way the guessing subject uses this information.
The Effects of Direct-Current Magnetic Fields on Turtle Retinas in Vitro
Authors: Raybourn Michael S.
Published: October 2006

Direct-current magnetic fields of 10 to 100 gauss cause a significant short-term reduction of the in vitro electroretinographic b-wave response in turtle retina. This response compression is not accompanied by the usual reduction in retinal sensitivity that occurs with background illumination. Furthermore, this effect is obtained only briefly after the offset of ambient lighting in the diurnal light-dark cycle of nonhibernating animals.
An Ultrahigh-Speed Analysis of Exocytosis: Nematocyst Discharge
Authors: Holstein T. , Tardent P.
Published: October 2006

High-speed microcinematography of nematocyst discharge in
Hydra attenuata
Pall. shows that this specialized exocytosis, which appears to result from an increase in the intracapsular pressure, requires a total of about 3 milliseconds. A maximum velocity of 2 meters per second is generated, corresponding to an acceleration of 40,000
g
. Thus nematocyst discharge is one of the fastest cellular processes in nature.
Reactive Metabolites From the Bioactivation of Toxic Methylfurans
Authors: Ravindranath Vijayalakshmi , Burka Leo T. , Boyd Michael R.
Published: October 2006

An important mechanism of toxicity of furans involves the cytochrome P-450 monooxygenase-catalyzed bioactivation of the compound in situ directly within the target tissues to highly reactive electrophilic products. The unsaturated aldehydes acetylacrolein and methylbutenedial have been identified as the principal reactive intermediates of 2- and 3-methylfuran, respectively, that are produced and bound covalently to tissue macromolecules in hepatic and pulmonary microsomal systems in vitro.
Amplification of N-
myc
in Untreated Human Neuroblastomas Correlates with Advanced Disease Stage
Authors: Brodeur Garrett M. , Seeger Robert C. , Schwab Manfred , Varmus Harold E. , Bishop J. Michael
Published: October 2006

A domain of DNA designated N-
myc
is amplified 20- to 140-fold in human neuroblastoma cell lines but not in cell lines from other tumor types. N-
myc
has now been found to be amplified in neuroblastoma tissue from 24 of 63 untreated patients (38 percent). The extent of amplification appears to be bimodal, with amplification of 100- to 300-fold in 12 cases and 3- to 10-fold in 10 others. Amplification was found in 0 of 15 patients with stage 1 or 2 disease, whereas 24 of 48 cases (50 percent) with stage 3 or 4 had evidence of N-
myc
amplification. These data indicate that N-
myc
amplification is a common event in untreated human neuroblastomas. Furthermore, N-
myc
amplification is highly correlated with advanced stages of disease (P < 0.001) and with the ability to grow in vitro as an established cell line, both of which are associated with a poor prognosis.
Insect Prothoracicotropic Hormone: Evidence for Two Molecular Forms
Authors: Bollenbacher Walter E. , Katahira Eva J. , O'Brien Martha , Gilbert Lawrence I. , Thomas Mark K. , Agui Noriaki , Baumhover Alfred H.
Published: October 2006

In an insect, the tobacco hornworm Manduca sexta, the cerebral neuropeptide prothoracicotropic hormone (PTTH), the primary effector of postembryonic development, exists as two molecular forms. These two PTTH's elicit characteristic in vitro dose responses of activation of prothoracic glands from different developmental stages, an indication that during development the glands change in their sensitivity to the neurohormones. Both PTTH's are active in a specific in situ bioassay. Since they may be released in situ at stage-specific times to evoke distinctly different developmental responses, the PTTH neuroendocrine axis appears to be an effective system for determining the functions of molecular forms of a neurohormone in the regulation of growth and development.