bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of Exogenous Type D Retrovirus from a Fibroma of a Macaque with Simian AIDS and Fibromatosis
Authors: Stromberg Kurt , Benveniste Raoul E. , Arthur Larry O. , Rabin Harvey , Giddens W. Ellis , Ochs Hans D. , Morton William R. , Tsai Che-Chung
Published: October 2006

A novel type D retrovirus was isolated by cocultivation of explants of fibromatous tissue from a rhesus monkey (
Macaca mulatta
) with immunodeficiency and retroperitoneal fibromatosis. This type D virus, isolated from a macaque with simian acquired immunodeficiency syndrome (SAIDS-D/Washington), is exogenous and is partially related to the Mason-Pfizer and the langur monkey type D viruses. The SAiDS-D virus can be distinguished from all other primate retroviruses by antigenicity and molecular hybridization. Nucleic acid hybridization studies reveal that the origin of the SAIDS-D isolate may reside in Old World monkey (subfamily Colobinae) cellular DNA.
O
-Acetylation of Disialoganglioside GD
3
by Human Melanoma Cells Creates a Unique Antigenic Determinant
Authors: Cheresh David A. , Reisfeld Ralph A. , Varki Ajit P.
Published: October 2006

Monoclonal antibody Mab D1.1 recognizes on human melanoma cells a ganglioside antigen characterized by an alkali-labile
O
-acetylated sialic acid residue. Immunochemical analysis showed that this molecule is an
O
-acetylated product of the neuroectoderm-associated disialoganglioside GD
3
. Controlled chemical
O
-acetylation of purified GD
3
resulted in the generation of this same epitope. Lysates of human melanoma cells were found to contain
O
-acetyltransferase activity capable of generating the antigenic epitope recognized by Mab D1.1. Thus, the addition of a single
O
-acetyl group to a common cell surface-associated ganglioside can create a potentially tumor-specific antigen.
Toxic Shock Syndrome and Lysogeny in
Staphylococcus aureus
Authors: Schutzer Steven E. , Fischetti Vincent A. , Zabriskie John B.
Published: October 2006

Lysogeny, or the presence of temperate bacteriophage, was demonstrated, by means of two
Staphylococcus aureus
indicator strains, in 11 of 12 strains of
S. aureus
isolated from patients with toxic shock syndrome. Only 1 of 18 strains of
S. aureus
that were not associated with toxic shock syndrome showed the presence of bacteriophage. A laboratory strain of
S. aureus
was lysogenized by bacteriophage from two of the toxic shock-associated strains. These results add support to the theory that lysogeny by one or more bacteriophage in certain strains of
S. aureus
may be responsible for the pathogenesis of toxic shock syndrome.
Legionnaires' Disease: Structural Characteristics of the Organism
Authors: Katz Sheila Moriber , Nash Philip
Published: October 2006

The Legionnaires' disease organism was isolated from lung tissue taken from two fatalities of the Legionnaires' disease epidemic that occurred in Philadelphia during 1976. In yolk sac tissue the agent grew as a small coccobacillary microorgansim, which was Gram variable and Gimenez positive. Intracellular coccoid and bacillary forms, detected by electron microscopy, within and without vacuoles, underwent multiplication by septate binary fission. Some of the intracellular forms resembled obligate intracellular pathogens. On defined bacteriologic media, the organisms were predominantly bacillary. The organism conforms to the morphologic criteria of a prokaryocyte.
Directional Selectivity in Hamster Superior Colliculus Is Modified by Strobe-Rearing But Not by Dark-Rearing
Authors: Chalupa Leo M. , Rhoades Robert W.
Published: October 2006

Visual response properties of superior collicular neurons of normal hamsters were compared with those of animals reared from birth to adulthood in either total darkness or with stroboscopic illumination. Directional selectivity was markedly reduced only in the strobe-reared animals, thus demonstrating visual plasticity in a system that develops apparently normally without visual experience.
Antibodies to Cerebroside Sulfate Inhibit the Effects of Morphine and β-Endorphin
Authors: Craves Frederick B. , Zalc Boris , Leybin Leonid , Baumann Nicole , Loh Horace H.
Published: October 2006

Morphine and β-endorphin inhibit the shaking response of pentobarbital-anesthetized rats to ice water. Stereotaxically guided administration of antibodies to cerebroside sulfate into the periaqueductal gray region, the most sensitive brain region in which to demonstrate inhibition of this response, antagonizes the effect of morphine and β-endorphin. These results suggest that cerebroside sulfate may be an integral component of an opiate receptor in rat brain.
Oxygen Consumption and Cellular Ion Transport: Evidence for Adenosine Triphosphate to O
2
Ratio Near 6 in Intact Cell
Authors: Harris Stuart I. , Balaban Robert S. , Mandel Lazaro J.
Published: October 2006

Oxygen (O
2
) consumption and net K
+
uptake were measured simultaneously upon reintroduction of K
+
into a K
+
-depleted suspension of renal tubules. The K
+
/O
2
stoichiometries of 11.8 ± 0.2 and 8.4 ± 0.6 were obtained for reduced nicotinamide adenine dinucleotide- and flavoprotein-linked substrates, respectively. These values complement classical K
+
to adenosine triphosphate (ATP) and ATP/O
2
stoichiometries, thereby demonstrating a remarkably efficient coupling between the processes of Na
+
- and K
+
-dependent adenosinetriphosphatase-mediated ion transport and oxidative phosphorylation within the intact cell.
Vitamin D Deficiency Inhibits Pancreatic Secretion of Insulin
Authors: Norman Anthony W. , Frankel Barbara J. , Heldt Anneliese M. , Grodsky Gerald M.
Published: October 2006

The effect of a vitamin D deficiency on insulin and glucagon release was determined in the isolated perfused rat pancreas by radioimmunoassay of the secreted proteins. During a 30-minute period of perfusion with glucose and arginine, pancreases from vitamin D-deficient rats exhibited a 48 percent reduction in insulin secretion compared to that for pancreases from vitamin D-deficient rats that had been replenished with vitamin D. Vitamin D status had no effect on pancreatic glucagon secretion. This result, along with the previously demonstrated presence in the pancreas of a vitamin D-dependent calcium-binding protein and cytosol receptor for the hormonal form of vitamin D, 1,25-dihydroxyvitamin D
3
, indicates an important role for vitamin D in the endocrine functioning of the pancreas.
Stress-Induced Eating Is Mediated Through Endogenous Opiates
Authors: Morley John E. , Levine Allen S.
Published: October 2006

The interaction of endogenous opiates and stress-induced eating in rats was evaluated by pharmacological manipulation. Eating induced by the tail-pinch method was inhibited by the opiate antagonist naloxone; after being repeatedly stressed over a 10-day period and then given naloxone, the rats behaved in a manner indistinguishable from the "wet-dog" shakes of opiate withdrawal. Thus endogenous opiates may have a role in the control of stress-related eating, a finding that may have therapeutic implications for humans.
Modulation of Epidermal Growth Factor Receptors on 3T3 Cells by Platelet-Derived Growth Factor
Authors: Wrann Michael , Fox C. Fred , Ross Russell
Published: October 2006

Platelet-derived growth factor does not compete with epidermal growth factor (EGF) for binding to EGF receptors on the murine 3T3 cell surface, but it modulates EGF receptors in two ways: (i) it induces a transient down regulation of EGF receptors and (ii) it inhibits EGF-induced down regulation of EGF receptors. These data suggest a common cellular internalization mechanism for the receptors for both hormones.
Binding and Mobility of the Cell Surface Receptors for 3,3′,5-Triiodo-L-Thyronine
Authors: Maxfield F. R. , Willingham M. C. , Pastan I. , Dragsten P. , Cheng S.-Y.
Published: October 2006

A fluorescent derivative of the thyroid hormone 3,3′,5-triiodo-L-thyronine binds to cultured mouse fibroblasts; such binding is saturable. Video intensification fluorescence microscopy indicates that binding occurs at the plasma membrane. Diffusion coefficients, obtained by fluorescence photobleaching recovery, are consistent with binding to a protein receptor on the cell surface.
Pentobarbital: Dual Actions to Increase Brain Benzodiazepine Receptor Affinity
Authors: Skolnick P. , Moncada V. , Barker J. L. , Paul S. M.
Published: October 2006

The binding of [
3
H]diazepam to benzodiazepine receptors was studied in extensively washed membranes of rat cerebral cortex in the presence of the depressant barbiturate, pentobarbital. Pentobarbital, like the endogenous neurotransmitter γ-aminobutyric acid (GABA), increased the basal binding and also potentiated the GABA-enhanced binding of [
3
H]diazepam to benzodiazepine receptors by increasing the apparent affinity of [
3
H]diazepam for the benzodiazepine receptor. The concentrations of pentobarbital necessary to elicit these effects in vitro are the same as those observed after treatment with pharmacologically relevant doses, suggesting that a common neurochemical association may exist between these two types of compounds.
Intestinal M Cells: A Pathway for Entry of Reovirus into the Host
Authors: Wolf Jacqueline L. , Rubin Donald H. , Finberg Robert , Kauffman Robert S. , Sharpe Arlene H. , Trier Jerry S. , Fields Bernard N.
Published: October 2006

Thirty minutes after inoculation of reovirus type 1 into the intestinal lumen of the mouse, viruses were found adhering to the surface of intestinal M cells but not other epithelial cells. Within 1 hour, viruses were seen in the M cell cytoplasm and were associated with mononuclear cells in the intercellular space adjacent to the M cell. These findings suggest that M cells are the site where reovirus penetrates the intestinal epithelium.
Calcium Spike Electrogenesis and Other Electrical Activity in Continuously Cultured Small Cell Carcinoma of the Lung
Authors: McCann Frances V. , Pettengill Olive S. , Cole James J. , Russell Jerome A. G. , Sorenson George D.
Published: October 2006

Spike electrogenesis, local depolarizing and hyperpolarizing responses, spontaneous rhythmic firing, and alternating resting potentials were measured in cells from a continuously cultured small cell carcinoma of the lung. Spike generation was blocked by MnCl
2
. In view of this evidence for calcium-spike electrogenesis and previous evidence of secretory activity in these cells, this cell line (DMS 53) can provide a model for the study of excitation-secretion behavior in human neoplastic cells.
Diethylstilbestrol Induces Neoplastic Transformation Without Measurable Gene Mutation at Two Loci
Authors: Barrett J. Carl , Wong Annette , McLachlan John A.
Published: October 2006

The frequency with which diethylstilbestrol induces neoplastic transformation and somatic mutation was measured concomitantly in Syrian hamster embryo cells. While diethylstilbestrol was as active as benzo[
a
]pyrene in inducing transformation, it failed to induce mutations at two conventionally studied loci. These results suggest that diethylstilbestrol may transform cells in the absence of gene mutations.
Biology of Hepatitis B Virus
Authors: Tiollais Pierre , Charnay Patrick , Vyas Girish N.
Published: October 2006

Immunochemical investigations of the viral antigens and molecular characterization of the viral DNA have elucidated the nature of the hepatitis B virus infection underlying acute, chronic, and oncogenic disorders of the liver in man. Cloning and sequencing of viral DNA have made possible studies on the structure of the genome and on certain aspects of the biology of the virus, hitherto constrained for a lack of tissue culture systems and laboratory animal models useful in its propagation.
Benzodiazepine Inhibition of the Calcium-Calmodulin Protein Kinase System in Brain Membrane
Authors: DeLorenzo Robert J. , Burdette Susan , Holderness Joy
Published: October 2006

Benzodiazepines inhibit Ca
2+
-calmodulin-stimulated membrane protein phosphorylation. The effects of the benzodiazepines on protein phosphorylation are stereospecific and produced by membrane-bound benzodiazepine. The potency of benzodiazepine kinase inhibition is correlated with the ability of the benzodiazepines to inhibit electric shock-induced convulsions. These findings provide evidence that some of the anticonvulsant and neuronal stabilizing effects of benzodiazepines may be modulated by the Ca
2+
-calmodulin protein kinase system and indicate that this calmodulin-kinase system represents an identifiable benzodiazepine receptor in brain that is distinguishable by several criteria from the previously described high-affinity benzodiazepine receptor.
Hindbrain GABA Receptors Influence Parasympathetic Outflow to the Stomach
Authors: Williford Daniel J. , Ormsbee Herbert S. , Norman Wesley , Harmon John W. , Garvey Thomas Q. , DiMicco Joseph A. , Gillis Richard A.
Published: October 2006

Blockade of γ-aminobutyric acid receptor function by direct microinjection of bicuculline into the nucleus ambiguus in cats produced a marked increase in gastric motility which was mediated by the vagus nerve. This effect was reversed by muscimol. These data indicate that the nucleus ambiguus may be an important brain site influencing gastric function and that the neurotransmitter controlling parasympathetic outflow from this nucleus to the stomach is γ-aminobutyric acid.
High Angiotensin-Converting Enzyme Activity in the Neurohypophysis of Brattleboro Rats
Authors: Chevillard C. , Saavedra J. M.
Published: October 2006

The activity of angiotensin-converting enzyme is significantly higher in the intermediate and posterior pituitary lobes of Brattleboro rats than in Long-Evans control rats. The high activity level was reversed by vasopressin treatment. Conversely, angiotensin-converting enzyme activity was significantly lower in the anterior pituitary of Brattleboro rats than in Long-Evans rats, and this activity level was not affected by vasopressin. These findings suggest an inverse relation between vasopressin and angiotensin systems in the posterior and intermediate lobes of the pituitary gland.
Osmotic Swelling of Phospholipid Vesicles Causes Them to Fuse with a Planar Phospholipid Bilayer Membrane
Authors: Cohen Fredric S. , Akabas Myles H. , Finkelstein Alan
Published: October 2006

Fusion of phospholipid vesicles with planar bilayer membranes occurs if the vesicles that contact the planar membrane swell osmotically after the replacement in their medium of an impermeant solute by a permeant one. This finding directly demonstrates that osmotic swelling is a driving force for vesicle-planar membrane fusion. The method used to induce vesicle swelling and fusion may have relevance for biological systems.
Nucleotide Sequence of the p21 Transforming Protein of Harvey Murine Sarcoma Virus
Authors: Dhar Ravi , Ellis Ronald W. , Shih Thomas Y. , Oroszlan Stephen , Shapiro Bruce , Maizel Jacob , Lowy Douglas , Scolnick Edward
Published: October 2006

Harvey murine sarcoma virus is a retrovirus which transforms cells by means of a single virally encoded protein called p21 has. We have determined the nucleotide sequence of 1.0 kilobase in the 5′ half of the viral genome which encompasses the has coding sequences and its associated regulatory signals. The nucleotide sequence has identified the amino acid sequence of two additional overlapping polypeptides which share their reading frames and the carboxyl termini with p21 but which contain additional NH
2
-terminal amino acids.
Induction of Melanized Cells from a Goldfish Erythrophoroma: Isolation of Pigment Translocation Variants
Authors: Matsumoto Jiro , Lynch Thomas J. , Grabowski Susan M. , Taylor John D. , Tchen T. T.
Published: October 2006

Melanization was induced in some cells of a goldfish tumor cell line (GEM-81) by cultivating the cells in autologous serum. The melanized cells continued to proliferate in vitro and several clones were isolated that differed with respect to cell morphology and intracellular distribution of pigment. Some of the clones consisted of cells able to translocate their melanosomes in response to epinephrine, melatonin, or adenosine 3′,5′-monophosphate.
Rabies Viruses Increase in Virulence When Propagated in Neuroblastoma Cell Culture
Authors: Clark H. F.
Published: October 2006

Several strains of attenuated rabies virus lacking the capacity to kill adult mice acquired a high lethal potential for mice after one to five serial passages in murine or human neuroblastoma cells. The virulence acquired after passage in neuroblastoma cells is a stable genetic trait retained during subsequent passage of viruses in nonneuroblastoma cell systems.
Postural Asymmetry and Movement Disorder After Unilateral Microinjection of Adrenocorticotropin 1-24 in Rat Brainstem
Authors: Jacquet Yasuko F. , Abrams Gary M.
Published: October 2006

A unilateral microinjection of adrenocorticotropin 1-24 in the rat brainstem in the region of the locus ceruleus resulted in postural asymmetry and movement disorder that resembled human dystonia, the severity and duration (2 to 3 days) being dose-dependent. These results show for the first time that neuropeptides in the brainstem may modulate posture and movement, and they suggest that some forms of movement disorder such as dystonia may be due to a disordered regulation of postural and locomotor mechanisms by adrenocorticotropin 1-24.
Fragment Spanning the SV40 Replication origin Is the Only DNA Sequence Required in cis for Viral Excision
Authors: Conrad Susan E. , Liu Chih-Ping , Botchan Michael R.
Published: October 2006

A 311-base pair fragment containing the SV40 origin of replication was linked to the chicken thymidine kinase gene on a recombinant plasmid. This molecule was transfected into human 143 thymidine kinase-deficient (TK
-
) cells, and colonies positive for thymidine kinase were selected. When cell lines derived from these colonies were fused to permissive simian cells that produce SV40 T antigen, the recombinant plasmid excised itself from the human cellular genome and replicated with a high copy number per cell. These results show that this segment of the viral genome is the only sequence required in cis to mediate SV40 excision and replication upon fusion to permissive cells. In addition, we have shown that excised plasmids apparently identical to the input DNA can be efficiently rescued in
Escherichia coli
. SV40 excision and replication may therefore be useful for the recovery of cloned genes from eukaryotic cells.
Protein Kinase Injection Reduces Voltage-Dependent Potassium Currents
Authors: Alkon Daniel L. , Acosta-Urquidi Juan , Olds James , Kuzma Gregory , Neary Joseph T.
Published: October 2006

Intracellular iontophoretic injection of the catalytic subunit of cyclic adenosine monophosphate-dependent protein kinase increased input resistance and decreased a delayed voltage-dependent K
+
current of the type B photoreceptor in the nudibranch
Hermissenda crassicornis
to a greater extent than an early, rapidly inactivating K
+
current (
I
A
). This injection also enhanced the long-lasting depolarization of type B cells after a light step. These findings suggest the involvement of cyclic adenosine monophosphate-dependent phosphorylation in the differential regulation of photoreceptor K
+
currents particularly during illumination. On the other hand, conditioning-induced changes in
I
A
may also be regulated by a different type of phosphorylation (for example, Ca
2+
-dependent).
Chromosome Localization of Highly Repetitive Human DNA's and Amplified Ribosomal DNA with Restriction Enzymes
Authors: Miller Dorothy A. , Choi Ye-Chin , Miller Orlando J.
Published: October 2006

Restriction endonucleases cut and partially removed DNA throughout fixed air-dried human metaphase chromosomes. Some enzymes produced a G-banding pattern; some revealed the presence of multiple chromosome-specific classes of highly repetitive DNA in C-band heterochromatin. Enzymes that produced the informative C-band patterns had recognition sequences that were four or five, but not six, base pairs long and did not contain a cytosine-guanine doublet. In both rat and human chromosomes, regions containing amplified ribosomal RNA genes were specifically removed by the restriction endonuclease Msp I.
Infection of Normal Human Epithelial Cells by Epstein-Barr Virus
Authors: Shapiro Ilya M. , Volsky David J.
Published: October 2006

Primary cultures of epithelial cells were grown from the tonsils and adenoids of patients with diseases not related to Epstein-Barr virus. The cells could not be infected by Epstein-Barr virus. Fluorescein-labeled Epstein-Barr virus and a cytofluorograph were then used to show that the epithelial cells do not have detectable receptors for the virus. However, implantation with Epstein-Barr virus receptors gave the cells the ability to bind the labeled virus. One to 5 percent of receptor-implanted cells exposed to the transforming B95-8 substrain of the virus expressed Epstein-Barr nuclear antigen. The early and viral capsid Epstein-Barr virus-determined antigens were not detected in the virus-infected cultures. The results show that normal human epithelial cells from the nasopharynx become susceptible to infection by Epstein-Barr virus when the membrane barrier resulting from the lack of viral receptors is overcome by receptor implantation.
Mobilization of Cellular Calcium-45 and Lead-210: Effect of Physiological Stimuli
Authors: Pounds JG , Mittelstaedt RA
Published: October 2006

Isolated rat hepatocytes in primary culture were used as a model system to evaluate the effects of selected hormones and culture conditions on the efflux of calcium-45 and lead-210 from cells labeled with these isotopes. Alpha-adrenergic stimuli, angiotensin, vasopressin, dibutyryl adenosine 3′,5′-monophosphate, and reduced phosphate concentrations in the medium increased the efflux of calcium-45 and lead-210. Glucagon and insulin had no effect, but increased phosphate concentrations decreased the efflux of both isotopes. Experiments with hepatocytes cultured in a medium free of calcium and lead demonstrated that the increased efflux of calcium-45 and lead-210 induced by hormones was the result of mobilization of the ions from intracellular stores. The data indicate that the physiological stimuli that mobilized calcium ions also mobilized lead ions, and that the mobilized lead would be available to interact with calcium-mediated cell functions.
Gene Transfer by Polyoma-Like Particles Assembled in a Cell-Free System
Authors: Slilaty Steve N. , Aposhian H. Vasken
Published: October 2006

Empty capsids of polyoma virus interact with DNA in a cell-free system to form polyoma-like particles (PLP). The DNA in these particles is protected from the action of pancreatic deoxyribonuclease. Transfer of genetic information by PLP has been accomplished by using a restriction fragment containing the transforming sequences of polyoma DNA as a model gene. Infection of rat F111 cells by PLP containing these sequences results in DNA-mediated cellular transformation. Gene transfer by PLP is 50 to 150 times more efficient than by the calcium phosphate precipitation method.
Protein Phosphatases: Properties and Role in Cellular Regulation
Authors: Ingebritsen Thomas S. , Cohen Philip
Published: October 2006

Protein phosphorylation is a principal regulatory mechanism in the control of almost all cellular processes. The nature of the protein phosphatases that participate in these reactions has been a subject of controversy. Four enzymes, termed protein phosphatases 1, 2A, 2B, and 2C, account for virtually all of the phosphatase activity toward phosphoproteins involved in controlling glycogen metabolism, glycolysis, gluconeogenesis, fatty acid synthesis, cholesterol synthesis, and protein synthesis. The properties, physiological roles, and mechanisms for regulating the four protein phosphatases are reviewed.
Entamoeba histolytica
Causes Intestinal Secretion: Role of Serotonin
Authors: McGowan Katherine , Kane Ann , Asarkof Nancy , Wicks Joan , Guerina Victoria , Kellum John , Baron Sherri , Gintzler Alan R. , Donowitz Mark
Published: October 2006

Lysates of the protozoan parasite
Entamoeba histolytica
altered active electrolyte transport when present on the serosal surface of rabbit ileum and rat colon. The lysate-induced effects on electrolyte transport were similar to those caused by serotonin, and were blocked by bufotenine, an analog known to inhibit the action of serotonin. The transport effects were partially inhibited by antibody to serotonin. The amebic lysates were shown to contain serotonin by radioimmunoassay, high-performance liquid chromatography, and thin-layer chromatography. These results suggest that the serotonin present in
Entamoeba histolytica
may be important in the diarrhea seen in amebiasis.
Subthreshold Excitatory Activity and Motoneuron Discharge During REM Periods of Active Sleep
Authors: Chase Michael H. , Morales Francisco R.
Published: October 2006

A striking paradox of the rapid eye movement periods of active sleep, which are typically characterized by the exacerbation of somatomotor atonia, is the occurrence of muscle twitches and jerks. The purpose of this study was to examine the specific motoneuron membrane potential processes responsible for these myoclonic patterns of activity. In lumbar motoneurons, examined intracellularly in the cat prepared for long-term study, these processes consisted of recurrent depolarizing membrane potential shifts and spontaneous action potentials that were either full-sized or of partial amplitude. In addition, the invasion of antidromically induced spikes into the soma was often blocked. Hyperpolarizing potentials were evident in the intervals between spontaneous spikes. Hyperpolarization was also observed immediately before depolarization and spike activity, in contrast to the gradual depolarization of the motoneuron membrane potential that always occurred during wakefulness. Thus, during rapid eye movement periods, in conjunction with muscle twitches and jerks, a strong excitatory input is superimposed on a background of inhibitory input. The unique patterns of membrane potential change that arise thus seem to result from the simultaneous coactivation of excitatory and inhibitory processes.
Lymphadenopathy Associated Virus Infection of a Blood Donor—Recipient Pair with Acquired Immunodeficiency Syndrome
Authors: Feorino P. M. , Kalyanaraman V. S. , Haverkos H. W. , Cabradilla C. D. , Warfield D. T. , Jaffe H. W. , Harrison A. K. , Gottlieb M. S. , Goldfinger D. , Chermann J.-C. , Barré-Sinoussi F. , Spira T. T. , McDougal J. S.. , Curran J. W.. , Montagnier L. , Murphy F. A. , Francis D. P.
Published: October 2006

A retrovirus isolated from three patients with the acquired immunodeficiency syndrome (AIDS) in the United States was morphologically and antigenically identical to lymphadenopathy associated virus isolated in France. Two of these isolates were from a blood donor-recipient pair, each of whom developed AIDS. Lymphadenopathy associated virus was isolated from the blood donor's lymphocytes 12 months after his onset of AIDS symptoms and from the blood recipient's lymphocytes 1 month after her onset of AIDS symptoms. Two isolates from the blood donor-recipient pair and an isolate from an epidemiologically unrelated homosexual man were examined by competitive radioimmunoassay to determine their antigenic relatedness to each other and to other human retroviruses. The major core proteins (p25) of the isolates were antigenically identical and all three isolates were identical to prototype lymphadenopathy associated virus isolated in France.
Recognition of HLA-A2 by Cytotoxic T Lymphocytes After DNA Transfer into Human and Murine Cells
Authors: van de Rijn Matthijs , Bernabeu Carmelo , Royer-Pokora Brigitte , Weiss John , Seidman John G. , de Vries Jan , Spits Hergen , Terhorst Cox
Published: October 2006

A gene coding for the major histocompatibility antigen HLA-A2 was transferred into human HLA-A2 negative M1 cells and murine L cells. Following transfection, these cells expressed molecules at the cell surface that are biochemically indistinguishable from HLA-A2 antigens on the human cell line JY from which the HLA-A2 gene was isolated. The M1A2 cells were recognized and lysed by a cytolytic T-cell clone specific for HLA-A2. The transfected L cells which express HLA-A2 in association with human β
2
-microglobulin were not lysed by this T-cell clone. The specific cytolysis of M1A2 cells could be inhibited by monoclonal antibodies to HLA-A2, and monoclonal antibodies to T3, T8, and LFA-1 on cytotoxic T lymphocytes. These results suggest that killing by allospecific T cells requires HLA-A2 antigens as well as other species-specific structures on the target cell surface.
Requirement for Signal Peptide Cleavage of
Escherichia coli
Prolipoprotein
Authors: Inouye Sumiko , Hsu Chian-Pin Sherman , Itakura Keiichi , Inouye Masayori
Published: October 2006

Oligonucleotide-directed site-specific mutagenesis was applied to alter the cleavage site in the signal peptide of the major outer membrane lipoprotein of
Escherichia coli
. Replacing the glycine residue at the cleavage site with an alanine residue did not affect the processing of the signal peptide. However, when the same cleavage site was constructed by the deletion of the glycine residue, the signal peptide was no longer cleaved. These results indicate that stringent structural integrity at the cleavage site in the lipoprotein signal sequence is required for correct processing of prolipoprotein.
Immunocytochemically Identified Vasopressin Neurons in Culture Show Slow, Calcium-Dependent Electrical Responses
Authors: Theodosis D. T. , Legendre P. , Vincent J. D. , Cooke I.
Published: October 2006

From morphological characterization and intracellular recordings, monolayer cultures derived from fetal mouse hypothalami were found to include functionally differentiated peptide neurons, a number of which appear to contain vasopressin. These cells exhibited particular patterns of slow, calcium-dependent membrane depolarizations, resembling in their periodicity and duration the phasic activity of vasopressin neurons recorded extracellularly in vivo.
Behavior and Phylogeny: Constriction in Ancient and Modern Snakes
Authors: Greene Harry W. , Burghardt Gordon M.
Published: October 2006

Comparative analyses of behavior have an underappreciated potential for revealing the role of ethoecological factors in the origins of higher taxa. Twenty-seven species (13 genera) in the advanced family Colubridae exhibited 19 patterns of coil application; one or two patterns were usually consistent within a genus. Forty-eight species (26 genera) in the primitive families Acrochordidae, Aniliidae, Boidae, and Xenopeltidae usually used a single pattern, despite differences in age, size, shape, habitat, and diet. This implies the shared retention of an action pattern used by their common ancestor no later than the early Paleocene. Constriction must have been used as a prey-killing tactic very early in the history of snakes and might have been a behavioral "key innovation" in the evolution of their unusual jaw mechanism.
Genes of the Major Histocompatibility Complex in Mouse and Man
Authors: Steinmetz Michael , Hood Leroy
Published: October 2006

The genes of the major histocompatibility complex code for cell-surface molecules that play an important role in the generation of the immune response. These genes and molecules have been studied intensively over the last five decades by geneticists, biochemists, and immunologists, but only recently has the isolation of the genes by molecular biologists facilitated their precise characterization. Many surprising findings have been made concerning their structure, multiplicity, organization, function, and evolution.
Studying Promoters and Terminators by Gene Fusion
Authors: Rosenberg Martin , Chepelinsky Ana B. , McKenney Keith
Published: October 2006

Prokaryotic gene control signals can be isolated, compared, and characterized by precise fusion in vitro to the
Escherichia coli
galactokinase gene (
galK
), which provides both a simple assay and genetic selection. This recombinant
galK
fusion vector system was applied to the study of promoters and terminators recognized by the
Escherichia coli
RNA polymerase. Three promoters created by mutation from DNA sequences having no promoter function were characterized. Mutations that inactivate promoter function were selected, structurally defined, and functionally analyzed. Similarly, transcription termination was examined, and mutations affecting terminator function were isolated and characterized.
Saccharomyces cerevisiae
Produces a Yeast Substance That Exhibits Estrogenic Activity in Mammalian Systems
Authors: Feldman David , Stathis Peter A. , Hirst Margaret A. , Stover E. Price , Do Yung S. , Kurz Walter
Published: October 2006

Partially purified lipid extracts of
Saccharomyces cerevisiae
contain a substance that displaces tritiated estradiol from rat uterine cytosol estrogen receptors. The yeast product induces estrogenic bioresponses in mammalian systems as measured by induction of progesterone receptors in cultured MCF-7 human breast cancer cells and by a uterotrophic response and progesterone receptor induction after administration to ovariectomized mice. The findings raise the possibility that bakers' yeast may be a source of environmental estrogens.
Pancreatic Islet Allograft Prolongation by Donor-Specific Blood Transfusions Treated with Ultraviolet Irradiation
Authors: Lau Henry , Reemtsma Keith , Hardy Mark A.
Published: October 2006

Survival of allografts of islets of Langerhans in nonimmunosuppressed adult rats was prolonged by transfusions of donor blood irradiated with ultraviolet light before transplantation across a major histocompatibility barrier. This treatment is donor blood-specific and has produced greater than 160-day survival of transplanted islets without the administration of immunosuppressive agents.
Common Region on Chromosome 14 in T-Cell Leukemia and Lymphoma
Authors: Hecht Frederick , Morgan Rodman , Hecht Barbara Kaiser-McCaw , Smith Stephen D.
Published: October 2006

Chromosome 14 breakpoints in malignant human lymphocytes cluster on the long (q) arm near bands q11 and q32. An inversion of chromosome 14 due to breaks in q11.2 and q32.3 has now been found in a newly established childhood T-cell lymphoma cell line and confirmed in T-cell chronic lymphocytic leukemia. A translocation was also found between chromosomes 10 and 14 with a breakpoint at 14q11.2 in another T-cell lymphoma cell line. It is proposed that a proximal region on chromosome 14 in or near sub-band q11.2 is related to T-cell function. Rearrangements in this region may affect the growth of T lymphocytes and be involved in the development of T-cell malignancies.
Medicine: Meritorious or Meretricious
Authors: Ingelfinger Franz J.
Published: October 2006

In spite of remarkable advances in medical therapy and in the development of fantastic diagnostic devices, American society appears increasingly disenchanted with the physician. The paradox can be explained by the high cost of medical care, the overselling of medicine's capabilities, the expectation that the physician will be both ultrascientific and as empathic as yesterday's doctor, and little recognition that the curing of one illness in the elderly exposes this group to other disease. Finally, though the physician is trained to manage illnesses, he is also given the excessively broad task of improving personal and societal practices disadvantageous to health.
Nitrate Synthesis in the Germfree and Conventional Rat
Authors: Green Laura C. , Tannenbaum Steven R. , Goldman Peter
Published: October 2006

Metabolic balance studies show that germfree and conventional Sprague-Dawley rats synthesize nitrate. Equivalent results for germfree and conventional rats eliminate the microflora as obligatory components of nitrate production. Nitrate synthesis appears to be a mammalian process.
Differential Development of Two Classes of Acetylcholine Receptors in
Xenopus
Muscle in Culture
Authors: Leonard R. J. , Nakajima S. , Nakajima Y. , Takahashi T.
Published: October 2006

Physiological properties of acetylcholine receptors on muscle cells at very early stages of ontogeny were compared with those of cells at later stages. Two changes were observed that contributed to an overall shortening of the mean open time of single-channels. First, there was a shift in the relative proportions of two receptor types with different conductances and mean open times, such that the contribution of receptors with large conductance and short open time increased as development proceeded. Second, there was a sharp reduction in the mean open time of channels having small conductance, with no similar change in channels having large conductance.
A Gradient of Sequence Divergence in the Human Adult α-Globin Duplication Units
Authors: Hess J. F. , Schmid C. W. , Shen C. K.
Published: October 2006

The nucleotide sequences of the two 5′-homology blocks of human α-globin gene duplication units were determined. The sequence difference between the two blocks is essentially zero in the 5′ portions, and increases gradually toward the 3′ ends until it reaches a value of 18 percent. This gradient of sequence divergence is similar to the distribution of the frequencies of gene conversion along several loci in
Ascobolus
and yeast. Hot spots for initiation of gene correction processes appear to exist near the 5′ ends of the human α-globin duplication units. The data provide the physical evidence for polar gene correction process in a mammalian genome.
Regulation of a Hybrid Gene by Glucose and Temperature in Hamster Fibroblasts
Authors: Attenello Janet W , Lee Amy Shiu
Published: October 2006

A novel eukaryotic hybrid gene has been constructed from the 5′ sequence of a rat gene and the bacterial neomycin-resistance gene. After transfection into hamster fibroblasts, the neo transcripts can be induced to high levels by the absence of glucose. Furthermore, this hybrid gene can be regulated by temperature when it is introduced into a temperature-sensitive mutant cell line.
Reaction of the Antitumor Antibiotic CC-1065 with DNA: Structure of a DNA Adduct with DNA Sequence Specificity
Authors: Hurley Laurence H. , Reynolds Vincent L. , Swenson David H. , Petzold Gary L. , Scahill Terry A.
Published: October 2006

Sequence-dependent variations in DNA revealed by x-ray crystallographic studies have suggested that certain DNA-reactive drugs may react preferentially with defined sequences in DNA. Drugs that wind around the helix and reside within one of the grooves of DNA have perhaps the greatest chance of recognizing sequence-dependent features of DNA. The antitumor antibiotic CC-1065 covalently binds through N-3 of adenine and resides within the minor groove of DNA. This drug overlaps with five base pairs for which a high sequence specificity exists.
Amino Acid Sequence of the Fc Region of a Canine Immunoglobulin M: Interspecies Homology for the IgM Class
Authors: Wasserman Richard L. , Capra J. Donald
Published: October 2006

The amino acid structure for the Fc portion of a canine immunoglobulin μ chain was determined. The sequence was compared with those of two human μ chains, and a high degree of interspecies homology was observed. The preservation of primary structure between species is probably reflective of the unique functions associated with the immunoglobulin M class.
Monoclonal Antibody to a Human Germ Cell Membrane Glycoprotein That Inhibits Fertilization
Authors: Naz Rajesh K. , Alexander Nancy J. , Isahakia Mohamed , Hamilton Marilyn S.
Published: October 2006

A monoclonal antibody to an antigen in the human germ cell membrane did not agglutinate or immobilize sperm but inhibited binding and penetration of zona-free hamster ova by human sperm and blocked murine fertilization in vitro. The antibody, of the 2a subclass of immunoglobulin G, was germ cell-specific but not species-specific. It recognized a single antigen of 23 kilodaltons that has been isolated from human germ cells. This fertilization antigen, located on the postacrosome, midpiece, and tail of human sperm, is a glycoprotein of testicular origin associated with some types of human involuntary immunoinfertility .
Molecular Indices of Cell Lineage Specification in Sea Urchin Embryos
Authors: Angerer Robert C. , Davidson Eric H.
Published: October 2006

The origins of several of the differentiated cell lineages of the advanced sea urchin embryo are well defined. Cytological application of molecular probes to three lineages, those responsible for the formation of the skeleton, the gut, and the aboral ectodermal wall of the late embryo, has demonstrated expression of lineage-specific genes long before overt morphological differentiation. These observations lead to useful generalizations regarding the processes of gene regulation that underlie the molecular biology of cell lineage specification in the embryo.
Antibodies to Human T-Cell Leukemia Virus Membrane Antigens (HTLV-MA) in Hemophiliacs
Authors: Essex M. , McLane M. F. , Lee T. H. , Tachibana N. , Mullins J. I. , Kreiss J. , Kasper C. K. , Poon M.-C. , Landay A. , Stein S. F. , Francis D. P. , Cabradilla C. , Lawrence D. N. , Evatt B. L.
Published: October 2006

Along with homosexual men, Haitians, and intravenous drug abusers, hemophiliacs are at high risk of contracting acquired immunodeficiency syndrome (AIDS). An earlier study revealed that 36 percent of a group of the AIDS patients had antibodies to cell membrane antigens associated with the human T-cell leukemia virus (HTLV-MA), whereas only 1.2 percent of matched asymptomatic homosexual controls had these antibodies. In the present experiments, serum samples from 172 asymptomatic hemophiliacs were examined for the presence of antibodies to HTLV-MA. Such antibodies were detected in 5 to 19 percent of the hemophiliacs examined from four geographical locations, but in only 1 percent or less of laboratory workers, normal blood donors, donors on hemodialysis, or donors with chronic active hepatitis.
Altered Activity Patterns During Development Reduce Neural Tuning
Authors: Sanes Dan H. , Constantine-Paton Martha
Published: October 2006

Neonatal mice were reared in an acoustic environment that repetitively entrained activity in a large proportion of primary auditory afferents during the period when the frequency tuning of auditory neurons normally develops. The tuning curves obtained from these mice were significantly broader than those of normally reared mice of the same age. This suggests that the normal frequency tuning of neurons was prevented or delayed by synchronizing the pattern of activity imposed on the auditory pathway.
Genetic Method for the Preferential Elimination of Females of
Anopheles albimanus
Authors: Seawright J. A. , Kaiser P. E. , Dame D. A. , Lofgren C. S.
Published: October 2006

Recent field experiments demonstrated the possibility of using the sterile male method for the control of Anopheles albimanus Wiedemann, the most important vector of human malaria in Central America. Until now there was no practical method for excluding females from the releases of sterile males. A genetic method was developed for the preferential elimination of females during any of the four life stages. This genetic sexing system utilizes propoxur (
o
-isopropoxyphenyl methyl-carbamate) susceptibility as a recessive conditional lethal, a T(Y:2R) translocation, and an In(2R)inversion. The propoxur resistance allele (dominant) was linked to the Y chromosome via a radiation-induced translocation, and genetic recombination was suppressed by inversions. In one of the strains produced, 99.7 percent of the females are eliminated when treated with propoxur, without male loss.
Chronically Decerebrate Rats Demonstrate Satiation But Not Bait Shyness
Authors: Grill Harvey J. , Norgren Ralph
Published: October 2006

Taste substances applied to the oral cavity result in either ingestion or rejection, each with a characteristic muscular response pattern. These responses are the same in decerebrate and intact rats; the caudal brainstem appears to be the neural substrate of ingestion and rejection responses. The experiment determined whether decerebrates can alter these discriminative responses as a function of food deprivation or toxicosis. Food-deprived decerebrate rats, like intact ones, ingested a taste substance they had rejected when sated. However, these same decerebrates, in contrast to controls, neither rejected nor decreased ingestive reactions to a novel taste after that taste had been repeatedly paired with lithium chloride-induced illness. Although the forebrain may be important for integrating ingestion, some aspects of this control seem to be represented in caudal brain areas.
Ponto-Geniculo-Occipital (PGO) Burst Neurons: Correlative Evidence for Neuronal Generators of PGO Waves
Authors: McCarley Robert W. , Nelson John P. , Hobson J. Allan
Published: October 2006

A newly discovered class of neurons, ponto-geniculo-occipital (PGO) burst neurons, has PGO wave relationships of phase-leading, stereotyped discharge bursts, and the highest reported discharge specificity and coherence; these neurons thus fulfill correlative criteria for output generator neurons for PGO waves. The PGO burst neurons are recorded in a discrete dorsal brainstem area in apposition to the brachium conjunctivum.
Platelet Thromboxane Synthetase Inhibitors with Low Doses of Aspirin: Possible Resolution of the "Aspirin Dilemma"
Authors: Bertelé Vittorio , Falanga Anna , Tomasiak Marian , Dejana Elisabetta , Cerletti Chiara , de Gaetano Giovanni
Published: October 2006

Selective pharmacological inhibition of thromboxane A
2
synthesis did not prevent arachidonate-induced aggregation of human platelets in vitro. Prevention was instead achieved by a combination of thromboxane A
2
inhibitors with low concentrations of aspirin. The latter partially reduced the proaggregatory cyclooxygenase products that accumulated when thromboxane A
2
synthesis was blocked. The aspirin concentrations did not affect per se either platelet aggregation or prostacyclin synthesis in cultured human endothelial cells. The combination of thromboxane synthetase inhibitors with low doses of aspirin may offer greater antithrombotic potential than either drug alone.
The Human Homologs of the
raf
(
mil
) Oncogene Are Located on Human Chromosomes 3 and 4
Authors: Bonner Tom , O'Brien Stephen J. , Nash William G. , Rapp Ulf R. , Morton Cynthia C. , Leder Philip
Published: October 2006

Two human genes that are homologous to both the murine transforming gene (oncogene) v-
raf
and the chicken transforming gene v-mil have been mapped by means of human-rodent somatic cell hybrids to human chromosomes previously devoid of known oncogenes. One gene, c-
raf
-2, which appears to be a processed pseudogene, is located on chromosome 4. The other gene, c-
raf
-1, which appears to be the active gene, is located on chromosome 3 and has been regionally mapped by chromosomal in situ hybridization to 3p25. This assignment correlates with specific chromosomal abnormalities associated with certain human malignancies.
Malignant Activation of a K-
ras
Oncogene in Lung Carcinoma But Not in Normal Tissue of the Same Patient
Authors: Santos Eugenio , Martin-Zanca Dionisio , Reddy E. Premkumar , Pierotti Marco A. , Della Porta Giuseppe , Barbacid Mariano
Published: October 2006

A single genetic alteration, a guanine-to-cytosine transversion, is responsible for the acquisition of malignant properties by K-
ras
genes of two human tumor cell lines established from carcinomas of the bladder (A1698) and lung (A2182). As a consequence, arginine instead of the normal glycine is incorporated into the K-
ras
-coded p21 proteins at amino acid position 12. This mutation creates a restriction enzyme polymorphism that can be used to screen human cells for transforming K-
ras
genes. This approach was used to identify the mutational event responsible for the malignant activation of a K-
ras
oncogene in a squamous cell lung carcinoma of a 66-year-old man; this point mutation was not present in either the normal bronchial or parenchymal tissue or in the blood lymphocytes. Hence, malignant activation of a
ras
oncogene appears to be specifically associated with the development of a human neoplasm.