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1.
J Psychiatr Res ; 110: 57-63, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30594025

RESUMO

Serotonergic function is known to fluctuate in association with light and temperature. Serotonin-related behaviors and disorders similarly vary with climatic exposure, but the associations are complex. This complexity may reflect the importance of dose and timing of exposure, as well as acclimation. This cross-sectional study tests how average climate exposures (ambient temperature and solar insolation) vary with the prevalence of a group of SSRI-treated disorders. For comparison, we similarly studied a group of disorders not treated by SSRIs (i.e substance use disorders). Psychiatric prevalence data were obtained from the Collaborative Psychiatric Epidemiology Surveys (CPES). Average yearly solar insolation was obtained from NASA's NLDAS-2 Forcing Dataset Information. Average yearly temperature was obtained from NOAA's US Climate Normals. Logistic regression models were generated to assess the relationship between these two climatic factors and the prevalence of SSRI-treated and substance use disorders. Age, gender, race, income, and education were included in the models to control for possible confounding. Temperature and insolation were significantly associated with the SSRI-responsive group. For an average 1 GJ/m2/year increase, OR was 0.90 (95% CI 0.85-0.96, p = 0.001), and for an average 10 °F increase, OR was 0.93 (95% CI 0.88-0.97, p = 0.001). This relationship was not seen with substance use disorders (insolation OR: 0.97, p = 0.682; temperature OR: 0.96, p = 0.481). These results warrant further investigation, but they support the hypothesis that chronic exposure to increased temperature and light positively impact serotonin function, and are associated with reduced prevalence of some psychiatric disorders. They also support further investigation of light and hyperthermia treatments.


Assuntos
Aclimatação , Transtornos de Ansiedade/epidemiologia , Bulimia Nervosa/epidemiologia , Clima , Transtorno Depressivo/epidemiologia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Serotonina/fisiologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Luz Solar , Temperatura , Adulto , Idoso , Transtornos de Ansiedade/tratamento farmacológico , Bulimia Nervosa/tratamento farmacológico , Estudos Transversais , Conjuntos de Dados como Assunto , Transtorno Depressivo/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
2.
Bioorg Med Chem Lett ; 9(23): 3341-6, 1999 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-10612596

RESUMO

Processing of trans-2-phenylcyclopropylmethanols 5 and 6 by the monocopper/tyrosine radical enzyme galactose oxidase led to mechanism-based inactivation with a partition ratio, (k(cat) + k(inact))/k(inact), of approximately 1 and a primary deuterium isotope effect, k(inact(H))/k(inact(D)), of 3.2. The data are consistent with a radical mechanism for galactose oxidase with a short lived ketyl radical anion intermediate.


Assuntos
Galactose Oxidase/metabolismo , Sondas Moleculares , Catálise , Galactose Oxidase/antagonistas & inibidores , Cinética
3.
Poult Sci ; 75(8): 1056-63, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8829240

RESUMO

The influences of brine composition, internal temperature, heating rate, and storage periods up to 28 d on flavor, texture, and color of sous vide processed chicken breast were evaluated. Pectoralis major muscles containing water and sodium chloride, with or without sodium lactate, were browned and vacuum packaged. Sous vide processing was by fast or slow heating to an internal temperature of 77 or 94 C. Product was evaluated after 0, 14, and 28 d storage at 4 C. Quality was evaluated by gas chromatographic analyses of flavor volatiles, shear, color, and sensory panels. Incorporation of sodium lactate into brine did not influence oxidative stability (as measured by headspace gas chromatography) or sensory warmed-over flavor. Presence of sodium lactate did result in enhanced fresh roasted or meaty and saltiness sensory scores as well as a more yellow color. The more rapid heating rate decreased sulfur-containing compounds and did not influence other volatile concentrations. Products processed to 94 C were less juicy, less tender, and contained higher quantities of alcohols and hydrocarbons than those processed to 77 C. Storage resulted in a decline in fresh roasted or meaty flavor note and an increase in warmed-over flavor note and quantities of alcohols, aldehydes and ketones, hydrocarbons, and total headspace volatiles.


Assuntos
Tecnologia de Alimentos/normas , Carne/normas , Aldeídos/análise , Animais , Galinhas , Cromatografia Gasosa/veterinária , Etanol/análise , Hidrocarbonetos/análise , Cetonas/análise , Músculo Esquelético/química , Músculo Esquelético/metabolismo , Oxirredução , Lactato de Sódio/farmacologia , Temperatura
4.
Astrophys J ; 467(2): 717-27, 1996 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-11541243

RESUMO

The high-latitude cloud (HLC) MBM 7 has been observed in the 21 cm H I line and the 12CO(1-0) and 13CO(1-0) lines with similar spatial resolutions. The data reveal a total mass approximately 30 M solar for MBM 7 and a complex morphology. The cloud consists of a cold dense core of 5 M solar surrounded by atomic and molecular gas with about 25 M solar, which is embedded in hotter and more diffuse H I gas. We derive a total column density N(H I + 2H2) of 1 x 10(21) cm-2 toward the center and 1 x 10(20) cm-3 toward the envelope of MBM 7. The CO line indicates the existence of dense cores [n(H2) > or = 2000 cm-3] of size (FWHM) approximately 0.5 pc. The morphology suggests shock compression from the southwest direction, which can form molecular cores along the direction perpendicular to the H I distribution. The H I cloud extends to the northeast, and the velocity gradient appears to be about 2.8 km s-1 pc-1 in this direction, which indicates a systematic outward motion which will disrupt the cloud in approximately 10(6) yr. The observed large line widths of approximately 2 km s-1 for CO suggest that turbulent motions exist in the cloud, and hydrodynamical turbulence may dominate the line broadening. Considering the energy and pressure of MBM 7, the dense cores appear not to be bound by gravity, and the whole cloud including the dense cores seem to be expanding. The distance to HLCs suggest that they belong to the galactic plane, since the scale height of the cloud is < or approximately equal to 100 pc. Compared to the more familiar dense dark clouds, HLCs may differ only in their small mass and low density, with their proximity reducing the filling factor and enhancing the contrast of the core and envelope structure.


Assuntos
Astronomia , Monóxido de Carbono/análise , Meio Ambiente Extraterreno , Fenômenos Astronômicos , Monóxido de Carbono/química , Gases/análise , Hidrogênio/química , Distribuição Normal , Análise Espectral
5.
J Anim Sci ; 70(5): 1397-403, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1526908

RESUMO

Eighty pigs (average weight of 60 kg) were allotted by weight and sex to pens and treatments. There were four dietary treatments, five pens per treatment, and four pigs per pen. Diets consisted of a typical corn-soybean mix containing 9% total fat, 3% from the corn-soybean mix and 6% added. The four dietary treatments included 1) 6% safflower oil, 2) 4% safflower oil and 2% tallow, 3) 2% safflower oil and 4% tallow, and 4) 6% tallow, resulting in 6.1, 4.6, 3.2, and 1.76% linoleic acid, respectively, in the diet. Pigs were slaughtered at an average weight of 100 kg. Proximate composition, tristimulus color coordinates (L, a, and b values), pH, and flavor difference of the longissimus muscle (LM) were evaluated. Fatty acid content (milligrams per 100 grams of tissue) of the subcutaneous fat and LM and headspace volatile content of the LM were determined by capillary gas liquid chromatography. Proximate composition, color, pH, and flavor of the LM were not influenced by diet. Fatty acid content of the subcutaneous fat and LM and volatile content of the LM were influenced by diet. Increased levels of safflower oil in the diet resulted in less C16:0 and C18:1 and more C18:2, C20:2, and C20:3 in the subcutaneous fat. The LM contained more C18:2 and less C18:3 and C24:0 due to increased levels of safflower oil in the diet. Compared with the 6% tallow diet, LM from pigs fed the 4 or 6% safflower diets contained more pentanal, hexanal, 2-heptanone, trans-2-heptenal, 2-pentyl furan, 2-ethyl-1-hexanol, decanal, and undecanal.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Gorduras na Dieta/administração & dosagem , Ácidos Graxos/análise , Ácidos Linoleicos/administração & dosagem , Carne/análise , Suínos/metabolismo , Tecido Adiposo/química , Tecido Adiposo/crescimento & desenvolvimento , Ração Animal , Animais , Feminino , Concentração de Íons de Hidrogênio , Masculino , Carne/normas , Desenvolvimento Muscular , Músculos/química , Suínos/crescimento & desenvolvimento , Paladar , Volatilização
6.
Astrophys J ; 355(2): 546-61, 1990 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11538683

RESUMO

We have made an observational study of the newly identified cyanomethane radical CH2CN and the possibly related species CH3CN with the goals of (1) elucidating the possible role of reactions of the type CnHm(+) + N in astrochemistry, and (2) providing a possible test of Bates's models of dissociative electron recombination. We find a remarkably different abundance ratio CH2CN/CH3CN in TMC-1 and Sgr B2, which we deduce is a result of the large difference in temperature of these objects. Studies of CH2CN and CH3CN in other sources, including two new detections of CH2CN, support this conclusion and are consistent with a monotonic increase in the CH2CN/CH3CN ratio with decreasing temperature over the range 10-120 K. This behavior may be explained by the destruction of CH2CN by reaction with O. If this reaction does not proceed, then CH2CN and CH3CN are concluded to form via different chemical pathways. Thus, they do not provide a test of Bates's conjectures (they do not both form from CH3CNH+). CH2CN is then likely to form via C2H4(+) + N --> CH2CNH+, thus demonstrating the viability of this important reaction in astrochemistry. The T dependence of the CH2CN/CH3CN ratio would then reflect the increasing rate of the C2H4(+) + N reaction with decreasing temperature.


Assuntos
Acetonitrilas/análise , Astronomia , Meio Ambiente Extraterreno , Fenômenos Astronômicos , Fenômenos Químicos , Química , Análise Espectral , Temperatura
7.
Astrophys J ; 334(2): L107-11, 1988 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11538463

RESUMO

We report the astronomical identification of the cyanomethyl radical, CH2CN, the heaviest nonlinear molecular radical to be identified in interstellar clouds. The complex fine and hyperfine structures of the lowest rotational transitions at about 20.12 and 40.24 GHz are resolved in TMC-1, where the abundance appears to be about 5 x 10(-9) relative to that of H2. This is significantly greater than the observed abundance of CH3CN (methyl cyanide) in TMC-1. In Sgr B2 the hyperfine structure is blended in the higher frequency transitions at 40, 80, and 100 GHz, although the spin-rotation doubling is clearly evident. Preliminary searches in other sources indicate that the distribution of CH2CN is similar to that for such carbon chain species as HC3N or C4H.


Assuntos
Acetonitrilas/análise , Meio Ambiente Extraterreno , Radicais Livres/análise , Hidrocarbonetos/análise , Acetonitrilas/química , Fenômenos Astronômicos , Astronomia , Fenômenos Químicos , Química , Radicais Livres/química , Análise Espectral
8.
Astrophys J ; 302: L31-6, 1986 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11542069

RESUMO

A new molecular ion, HCNH+, or protonated HCN, has been detected in the interstellar medium. The J = 1-0, 2-1, and 3-2 rotational transitions of this species have been observed toward Sgr B2. Using a large velocity gradient model calculation, the column density of HCNH+ is found to be approximately 4 x 10(14) cm-2, about one order of magnitude less than that estimated for HCO+ and HCN in this source. Such a column density implies a fractional abundance for HCNH+ in Sgr B2 of approximately 3 x 10(-10), one to several orders of magnitude greater than the values predicted by ion-molecule models of interstellar chemistry. The high observed abundance of this species, relative to theoretical calculations, suggests that the destruction of HCNH+ by dissociative recombination is slower than expected, or that the formation rate of the ion has been underestimated.


Assuntos
Meio Ambiente Extraterreno , Cianeto de Hidrogênio/química , Fenômenos Astronômicos , Astronomia , Cianeto de Hidrogênio/análise , Íons , Micro-Ondas , Modelos Teóricos , Prótons , Análise Espectral
9.
Astrophys J ; 300(1): L19-23, 1986 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11542068

RESUMO

Vibrationally excited HCN has been observed for the first time in the interstellar medium. The J = 3-2 rotational transitions of the l-doubled (0,1(1d,1c), 0) bending mode of HCN have been detected toward Orion-KL and IRC +10216. In Orion, the overall column density in the (0,1,0) mode, which exclusively samples the "hot core", is 1.7 x 10(16) cm-2 and can be understood in terms of the "doughnut" model for Orion. The ground-state HCN column density implied by the excited-state observations is 2.3 x 10(18) cm-2 in the hot core, at least one order of magnitude greater than the column densities derived for HCN in its spike and plateau/doughnut components. Radiative excitation by 14 micrometers flux from IRc2 accounts for the (0,1,0) population, provided the hot core is approximately 6-7 x 10(16) cm distant from IRc2, in agreement with the "cavity" model for KL. Toward IRC +10216 we have detected J = 3-2 transitions of both (0,1(1c),(1d), 0) and (0, 2(0), 0) excited states. The spectral profiles have been modeled to yield abundances and excitation conditions throughout the expanding envelope.


Assuntos
Meio Ambiente Extraterreno , Cianeto de Hidrogênio/análise , Fenômenos Astronômicos , Astronomia , Simulação por Computador , Micro-Ondas , Modelos Teóricos , Análise Espectral
10.
J Mol Evol ; 15(2): 79-101, 1980 May.
Artigo em Inglês | MEDLINE | ID: mdl-6995621

RESUMO

The study of interstellar molecules broadly includes two areas of interest. One area uses the unique ability of molecules to act as probes of the physical conditions in the cold, dense, visually opaque component of the interstellar medium. The physical properties of this and other components of the interstellar medium are summarized. The other area deals with the chemistry of interstellar molecules, recent aspects of which are emphasized in this review. Gas-phase chemistry, shock chemistry, and grain surface chemistry are discussed in the context of recent observations. No present observations suggest that surface reactions are relevant, but neither can they be ruled out. Ion-molecule reactions are clearly operative, at least for the simpler species. Chemical isotope fractionation is reviewed, and it is concluded that the complexities of the chemistry allow no cosmological conclusions to be drawn from observations of deuterium in interstellar molecules, while the presence of 13C in interstellar molecules permits an estimate of the 12C/13C ratio which is consistent with the current concepts of the nucleosynthesis history of the Galaxy. Possible connections between interstellar molecules and the early molecular history of the solar system are discussed.


Assuntos
Meio Ambiente Extraterreno , Gases , Evolução Biológica , Fenômenos Químicos , Química , Íons , Isótopos , Propriedades de Superfície
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