Showing papers by "Research Triangle Park published in 1977"
TL;DR: A striking increase in the incidence of myocardial infarction appears to have occurred in the Japanese who migrated to the United States; this increase is more pronounced in California than in Hawaii.
Abstract: The incidence of myocardial infarction and death from coronary heart disease was studied in defined samples of 45 to 68 year old Japanese men in Japan, Hawaii and California. The incidence rate was lowest in Japan where it was half that observed in Hawaii (P less than 0.01). The youngest men in the sample in Japan were at particularly low risk. The incidence among Japanese men in California was nearly 50 percent greater than that of Japanese in Hawaii (P less than 0.05). A striking increase in the incidence of myocardial infarction appears to have occurred in the Japanese who migrated to the United States; this increase is more pronounced in California than in Hawaii.
469 citations
TL;DR: Three ADA (adenosine deaminase) inhibitors, DHMPR, EHNA and deoxycoformycin (a transition state analog), were classified as readily reversible, semi-tight-binding and tight-binding inhibitors.
366 citations
TL;DR: Isomers which are chlorinated in only one ring, or are chlorination in both rings but not in the para positions, have very little activity as inducers of liver enzymes.
238 citations
TL;DR: The increased coronary risk profile in Hawaii compared with Japan can account for the greater incidence of coronary heart disease in the former.
Abstract: Various risk factors were evaluated to explain a significantly greater incidence of coronary heart disease in men of Japanese ancestry resident in Hawaii compared with men resident in Japan. The independent predictors of incidence of coronary heart disease in both Japan and Hawaii were systolic blood pressure, serum cholesterol, relative weight and age. These factors appeared to influence incidence similarly in both areas because in each case the correlation coefficients for Japan and Hawaii did not differ significantly. The hypothesis that the greater incidence in Hawaii could be attributed to differences in levels of these risk factors was tested with the Walker-Duncan method. The four variable multiple logistic function describing the probability of coronary heart disease in Japan was applied to the cohort characteristics observed in Hawaii. The estimated incidence thus obtained was not significantly different from that actually observed in the men resident in Hawaii. Therefore the increased coronary risk profile in Hawaii compared with Japan can account for the greater incidence of coronary heart disease in the former. Current cigarette smoking was significantly related to the risk of coronary heart disease in Hawaii but not in Japan. This difference requires further investigation.
198 citations
TL;DR: In this paper, the polymerization of organic compounds in glow discharge (plasma polymerization) was investigated by using pulsed R.F. discharge (100 μsec on, 900 μsec off).
Abstract: The polymerization of organic compounds in glow discharge (plasma polymerization) was investigated by using pulsed R.F. discharge (100 μsec on, 900 μsec off). The effects of pulsed discharge on polymer deposition rate, pressure change in plasma, ESR signals of free spins in both plasma polymer and substrate, and the contact angle of water on the plasma polymer surface were investigated for various organic compounds. The results are correlated to the mechanisms of polymer formation in plasma (plasma polymerization) which has been postulated as repeating processes of stepwise (propagation) reactions. The effect of the pulse is different from one group of organic compounds to another depending on whether or not they contain an olefinic double bond and/or a triple bond. The main difference seems to be the addition polymerization which can occur exclusively during the off-period of pulsed discharge. Ultraviolet emission from pulsed discharge is much less than from continuous discharge. Consequently, the fragmentation of the monomer and the free-radical formation in the substrate are less with the pulsed discharge. Properties of polymers from some organic compounds formed in continuous and in pulsed discharge were found to be significantly different, and the differences were postulated from the changes of polymerization mechanisms in the pulsed discharge.
194 citations
TL;DR: Cyclic AMP may play a crucial role in the regulation of platelet phospholipase acitivity, and this could explain at least in part the inhibition of aggregation caused by substances which, like prostacyclin, raise the levels of cyclicAMP.
192 citations
TL;DR: The eluate from the insulin-agarose column demonstrated a major band with an apparent molecular weight of 135,000 on SDS polyacrylamide gel electrophoresis, and because of the possibility of anomalous SDS binding, this molecular weight must be accepted with caution.
179 citations
TL;DR: In this article, surfaces of polymers [polyethylene, polystyrene, poly(ethylene terephthalate), poly(oxymethylene), cellulose acetate, polyacrylonitrile, nylon 6, polytetrafluoroethylene] treated with argon (inert) and nitrogen (reactive) plasma were examined by ESCA (electron spectroscopy for chemical analysis).
Abstract: Surfaces of polymers [polyethylene, polystyrene, poly(ethylene terephthalate), poly(oxymethylene), cellulose acetate, polyacrylonitrile, nylon 6, and polytetrafluoroethylene] treated with argon (inert) and nitrogen (reactive) plasma were examined by ESCA (electron spectroscopy for chemical analysis). Argon plasma treatment generally introduces oxygen functionalities into the polymer surface. Nitrogen treatment generally incorporates nitrogen and oxygen functionalities into the treated surface. The extent of oxygen incorporation is typically less than that produced by argon plasma. When nitrogen and oxygen functional groups are already in a polymer structure, the extent of additional incorporation of these two elements as a result of plasma treatment is very much less than with other polymers. Polymers which contain only one of the elements tend to incorporate the other element to much the same degree as polymers without either element initially present.
152 citations
TL;DR: In this article, a multilayer model is proposed which predicts the equilibrium sorption isotherms for pure gases in Part I and for binary gas mixtures in Part II.
Abstract: A multilayer model is proposed which predicts the equilibrium sorption isotherms for pure gases in Part I and for binary gas mixtures in Part II. This first part deals with the sorption of a pure g...
136 citations
TL;DR: The carbon cycle of a loblolly pine plantation in North Carolina was examined during its 12th through 16th years from planting and autotrophic respiration rates found to be closely coupled to regional temperature.
Abstract: The carbon cycle of a loblolly pine plantation in North Carolina was examined during its 12th through 16th years from planting. Net primary production during the study period averaged 2056 g C m-2 year-1. With autotrophic respiration equal to 2068 g C, the calculated gross production was 4124 g C m-2 year-1. Heterotrophic respiration of 694 g C m-2 year-1 resulted in net ecosystem production of 1362 g C m-2 year-1. In carbon cycle comparisons between forest ecosystems, autotrophic respiration rates were found to be closely coupled to regional temperature.
119 citations
TL;DR: The relationship of high ozone (ozone in excess of the National Ambient Air Quality Standards) with high pressure systems was examined using data collected in the summer of 1973, 1974 and 1975.
TL;DR: Since thromboxane A2 induces platelet aggregation and is a potent vasoconstrictor, diversion of pathways to prostaglandins with opposite or less potent action might be of relevance in the treatment of cardiovascular diseases.
TL;DR: Results of this study suggest that the different MAO sites could be part of the same large molecular complex, which may normally be embedded in the outer mitochondrial membrane so that A sites are more dependent on their lipid environment within this membrane.
Abstract: — MAO of human brain and liver mitochondria was solubilized by a procedure that preserved the substrate and inhibitor selectivities of the original mitochondrial preparation. Techniques that are designed to separate proteins on the basis of molecular size or net surface charge did not yield a physical separation of enzymically active A and B forms, even in the presence of ionic detergents or with limited proteolysis. However, sulfhydryl inhibitors, inorganic salts, ionic detergents, heat treatment, and sonication all tended to cause selective inactivation of serotonin-metabolizing activity in solubilized preparations. Experiments with selectively inhibited (membrane-bound or solubilized) MAO supported the concept of at least two independent kinds of substrate binding site, only one of which metabolizes serotonin (A type) and another (B type) which has a very strong affinity for β-phenethylamine. l-Norepinephrine, tryptamine, dopamine, and tyramine could be classified as common substrates. The lowest Km values were found for tryptamine at A sites and for β-phenethylamine at B sites. Results of this study suggest that the different MAO sites could be part of the same large molecular complex, which may normally be embedded in the outer mitochondrial membrane so that A sites are more dependent on their lipid environment within this membrane.
TL;DR: In the course of examining the complete dose-response relationship for the behavioral effects of LSD in the cat, it was discovered that, in addition to large increases in investigatory and hallucinatory-like responses, two behaviors, not previously reported, are emitted with a high probability under LSD.
TL;DR: It is concluded that technical pentachlorophenol produces a number of liver changes which cannot be attributed to pentach chlorophenol itself, but are consistent with the effects of biologically active chlorinated dibenzo-p-dioxins and dibenzofurans.
TL;DR: Both [Met 5 ] and [Leu 5 ]-enkephalins inhibit 3 H-naloxone binding to brain opiate receptors much more effectively at 4°C than at 25°C, and their action is not potentiated by bacitracin.
TL;DR: Excess mortalities observed after 20 daily 3-hour exposures suggested that a synergistic effect might be present upon repeated inhalation of pollutant mixtures, that made them more effective in reducing resistance to respiratory infection.
TL;DR: The effectiveness of orally administered pseudoephedrine in patients with acute or chronic nonsuppurative rhinitis was evaluated under double-blind conditions and it is suggested that pseudoepinghedrine is an orally effective nasal decongestant.
Abstract: The effectiveness of orally administered pseudoephedrine in patients with acute or chronic nonsuppurative rhinitis was evaluated under double-blind conditions. Intranasally administered ephedrine which was given to all patients at the end of this study served as the positive control. Marked nasal decongestant effects of a single oral dose of pseudoephedrine (60 mg tablet), as determined by a modified passive anterior, rhinometric technique occurred within 30 minutes and were maintained for at least four hours. The mean nasal decongestant response (delta % of baseline) of 57.2% was associated with a mean peak, plasma pseudoephedrine level of 274 ng/ml. In addition, the maximum response to oral pseudoephedrine treatment was equivalent to the response produced by ephedrine nasal spray. These results suggest that pseudoephedrine is an orally, effective nasal decongestant.
TL;DR: Radioimmunoassay (RIA) was used to determine several pharmacokinetic parameters of codeine in man, including the relative bioavailability after oral and intramuscular administration, and codeine concentrations were determined by a specific RIA procedure.
Abstract: Radioimmunoassay (RIA) was used to determine several pharmacokinetic parameters of codeine in man, including the relative bioavailability after oral and intramuscular administration. The study followed a crossover design in 6 healthy, young (18 to 21 yr), male volunteers. Three subjects received 65 mg codeine phosphate orally in an analgesic mixture which also contained aspirin, phenacetin, and caffeine. At the same time a similar group received an equivalent dose of codeine phosphate in a single intramuscular injection. Two weeks later the study was repeated so that each group received the alternate treatment. Plasma samples were collected at various times after drug administration, and codeine concentrations were determined by a specific RIA procedure. The procedure can detect less than 50 pg of codeine. Following intramuscular administration, peak plasma concentrations (194 to 340 ng/ml) were observed between 0.25 to 1 hr; after oral dosing, peak codeine plasma concentrations (102 to 140 ng/ml) appeared within 0.75 to 1 hr. The mean plasma t1/2 and volume of distribution of codeine following intramuscular injection were 3.32 hr and 5.1 L/kg, respectively. Oral, relative to intramuscular, bioavailability of codeine, based on areas under the codeine plasma curves, was 42% to 71% (mean, 53%).
TL;DR: The above studies indicate that the plasma clearance of caffeine is markedly increased in rats pretreated with phenobarbital, PCH, or Aroclor 1254 and suggest that the metabolism and pharmacology of caffeine may be considerably altered in human subjects exposed to these substances.
Abstract: A thin‐layer chromatographic method is described for the quantitation of caffeine and its dimethylxanthine metabolites, theophylline, theobromine, and paraxanthine. The method was used to evaluate the effect of polycyclic aromatic hydrocarbons (PCH), polychlorinated biphenyls (Aroclor 1254), or phenobarbital on the pharmacokinetics of caffeine and its dimethylxanthine metabolites. The oral administration of benzo[a] pyrene (BP) or Aroclor 1254 to rats for 3 days markedly increased the plasma clearance of caffeine and its dimethylxanthine metabolites. Similar results on the plasma clearance of caffeine were obtained with benzanthracene, dibenzanthracene, chrysene, or pyrene. Although the elimination of caffeine from plasma was increased in rats treated with phenobarbital for 3 days, it was less effective in this respect than the PCH or Aroclor 1254. In addition, phenobarbital did not significantly affect the rate of elimination of the dimethylxanthine metabolites from rat plasma following an intravenous dose of caffeine. Following the intravenous administration of caffeine to rats pretreated with Aroclor 1254 or BP, there was a marked increase in the appearance of theophylline, theobromine, and paraxanthine in plasma. The time to achieve peak plasma levels of these metabolites was reduced from 6 to 7 hr in control rats to I hr in Aroclor 1254‐treated rats and to less than 3 hr in rats treated with BP. Moreover, the plasma elimination of the dimethylxanthine metabolites formed from caffeine was greatly accelerated after pretreatment with BP or Aroclor 1254. A dose‐response study with BP indicated that as little as 1.0 mglkg of BP administered orally for 3 days markedly increased the plasma clearance of caffeine; however, pretreatment with BP did not affect the absolute bioavailability of caffeine. The area under the caffeine plasma curve after oral administration was identical to the area when the same dose was administered intravenously. The above studies indicate that the plasma clearance of caffeine is markedly increased in rats pretreated with phenobarbital, PCH, or Aroclor 1254 and suggest that the metabolism and pharmacology of caffeine may be considerably altered in human subjects exposed to these substances.
TL;DR: The investigators used amounts of toxic gases whose cumulative total equaled the total in the continuous exposures, and intercalated the intermittent exposures with periods of nonpolluted air to equal the cumulative total concentration of the single continuous exposures.
Abstract: Because of fluctuations in levels of industrial air pollution linked to weather and other factors, a joint U.S.‐Soviet research team studied differences in the effect of time in exposures of air‐breathing animals to controlled varied concentrations of air pollutants. An experimental model environment was used to investigate the effects of nitrogen dioxide (NO2), sulfur dioxide (SO2), and benzene (C6H6) in the air environment of laboratory animals, with both continuous and intermittent exposures. For intermittent exposures the investigators used amounts of toxic gases whose cumulative total equaled the total in the continuous exposures, and intercalated the intermittent exposures with periods of nonpolluted air. To equal the cumulative total concentration of the single continuous exposures over an equal time period, the concentrations of toxic gases were necessarily greater in the intermittent exposures. Part I of this work deals with the effects of continuous exposure to C6 H6 on the central nervous syste...
TL;DR: The determination of the amino acid sequence of the dihydrofolate reductase from Escherichia coli RT500, comprising 159 residues, has been derived from automatic sequencing of the intact protein in conjunction with manual sequencing of lysine-blocked tryptic peptides, Staphylococcus aureus protease peptide, and alpha-lytic prote enzyme peptides.
Abstract: The determination of the amino acid sequence of the dihydrofolate reductase from Escherichia coli RT500 is described. The sequence, comprising 159 residues, has been derived from automatic sequencing of the intact protein in conjunction with manual sequencing of lysine-blocked tryptic peptides, Staphylococcus aureus protease peptides, and α-lytic protease peptides. Comparison of the sequence with that of the dihydrofolate reductase from a methotrexate-resistant strain of E. coli (MB1428) shows that 145 of the residues are identical. The distribution of the differences along the length of the molecule is discussed.
TL;DR: In this paper, the interaction between air pollutants and solar radiation is discussed in terms of measurements of the direct solar beam to determine atmospheric turbidity; the role of solar radiation in initiating photochemical smog processes; and urban-rural differences of incident solar energy.
TL;DR: It follows from the data presented that inhalation of this metal can inhibit the normal mucociliary function vital for clearance of agents from the respiratory tract.
TL;DR: Leucine‐enkephalin and some analogues were assayed for activity in vitro on the mouse vas deferens and for binding to opiate receptors from rat brain and a small subset of the conformations examined was found to be compatible with the experimental data.
Abstract: 1. Leucine-enkephalin and some analogues were assayed for activity in vitro on the mouse vas deferens and for binding to opiate receptors from rat brain. 2. The experimental data were analysed in terms of the stringency for glycine, a D-amino acid or an L-amino acid at each position in the peptide. 3. The observed configurational specificity was compared with the stringency that would be predicted to occur if enkephalin adopted certain hydrogen-bonded conformations at the receptor. 4. A small subset of the conformations examined was found to be compatible with the experimental data.
TL;DR: In this paper, the effects of ozone (O 3 ) and sulfuric acid (H 2 SO 4 ) aerosol on host susceptibility to an aerosol of viable microorganisms were studied.
TL;DR: In this article, the authors estimate the internal stress in a thin layer of plasma polymer on the surface of a substrate showing a tendency to expand, indicating an internal stress, σs, from the observed curling of composite membranes.
Abstract: Owing to the unique mechanisms operative in plasma polymerization, a thin layer of plasma polymer deposited on the surface of a substrate shows a tendency to expand, indicating an internal stress in the layer. This stress, σs, has been estimated from the observed curling of composite membranes in which the thickness of the plasma coating, d, is much smaller than the thickness of a flexible substrate, D, according to the relation
where R is the radius of the roll into which the composite films curl up and E is the modulus of the substrate polymer. The stress σs is found to depend on the kind of monomer used and to be of the order of magnitude 108–109 dynes/cm2 with most of the monomers here employed.
TL;DR: Ganglioside GM 1 has been measured after insertion into transformed fibroblasts by cholera toxin (choleragen) binding, for which gangliosid GM 1 is the natural receptor.