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1.
Addict Behav ; 25(1): 93-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10708322

RESUMEN

Alcohol outcome expectancies have been linked to drinking behavior on both empirical and theoretical grounds. Although typically measured as a static construct, we hypothesized that expectancies may be time-specific. Subjects rated their expectancies for a moderate amount of alcohol to increase, decrease, or not change their level of tension and anxiety. Ratings were repeated for when the intoxicating effects of the drinking would be: (1) "at their peak;" (2) "nearly worn off;" and (3) "completely worn off" (Time Epochs 1-3, respectively). As predicted, most subjects (72%) expected alcohol to reduce tension and anxiety at Time Epoch 1; however, significantly fewer subjects expected this effect at Time Epochs 2 and 3 (25% and 2%, respectively). Conversely, few subjects expected alcohol to worsen tension and anxiety at Time Epoch 1 (3.5%); however, significantly more subjects expected this effect at Time Epochs 2 and 3 (31% and 34%, respectively). Expectancies for Time Epoch 1 related most strongly to several measures of alcohol use, including drinking for the purpose of reducing tension (whole sample) and drinking frequency (men but not women). These findings show that tension-reduction expectancies are not stable over the course of a drinking episode and suggest the possibility of a treatment approach aimed at amplifying attention to expectancies for alcohol's more negative longer-term effects.


Asunto(s)
Consumo de Bebidas Alcohólicas/psicología , Ansiedad/psicología , Nivel de Alerta/efectos de los fármacos , Disposición en Psicología , Adulto , Consumo de Bebidas Alcohólicas/efectos adversos , Intoxicación Alcohólica/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Motivación , Inventario de Personalidad , Factores de Tiempo
2.
J Bacteriol ; 162(2): 494-503, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-3886625

RESUMEN

Cultures of Salmonella typhimurium pulse-labeled with N-acetyl-D-[3H]glucosamine ([3H]GlcNAc) incorporated isotope into a GlcNAc-linked lipid that was tentatively identified as GlcNAc-pyrophosphorylundecaprenol. The incorporation of [3H]GlcNAc into this compound was abolished when cells were pulse-labeled in the presence of the antibiotic tunicamycin. Tunicamycin also abolished the in vivo synthesis of the haptenic form of enterobacterial common antigen (ECA) in S. typhimurium as determined by the passive hemagglutination test. These data indicated that the synthesis of the GlcNAc-linked lipid is related to ECA synthesis. Support for this conclusion was provided by the following observations. Cultures of Escherichia coli and S. typhimurium incorporated [3H]GlcNAc into cell envelope components that migrated as a homologous series of polymers when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The [3H]GlcNAc-labeled polymers were not detected in mutants of E. coli and S. typhimurium defective in ECA synthesis due to lesions in either the rfe or rff gene clusters. These polymers were identified as ECA based on Western blot analyses employing anti-ECA monoclonal antibody. The incorporation of [3H]GlcNAc into ECA polymers was abolished by tunicamycin when the drug was added to cultures to give a minimum concentration of 3 micrograms/ml. In addition, pulse-chase experiments provided evidence for a precursor-product relationship between the GlcNAc-linked lipid and ECA. These results strongly suggest that the GlcNAc-linked lipid is involved in the biosynthesis of ECA in a manner analogous to the role of carrier lipid in the biosynthesis of O-antigen and peptidoglycan.


Asunto(s)
Antígenos Bacterianos/análisis , Enterobacteriaceae/inmunología , Lipopolisacáridos/biosíntesis , Polisacáridos Bacterianos/biosíntesis , Acetilglucosamina/metabolismo , Enterobacteriaceae/metabolismo , Glucolípidos/biosíntesis , Salmonella typhimurium/metabolismo , Tunicamicina/farmacología
3.
Vet Pathol ; 21(4): 432-41, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6380093

RESUMEN

The morphological and biochemical consequences of transplanting affected bone marrow from donor BALB/c mice with a lysosomal storage disorder (BALB/c LSD) into normal recipient mice were studied. Bone marrow was removed from normal BALB/c and BALB/c LSD mice and transfused into normal BALB/c recipient mice four hours after the mice received 850 rads of irradiation. Tissues of the recipient mice were examined 240 days later. This study revealed that the defective cells that constituted the visceral lesions of BALB/c LSD could be transplanted to normal BALB/c mice by the use of bone marrow from affected BALB/c LSD homozygote; that the defective cells of BALB/c LSD proliferated and disseminated throughout the mononuclear phagocytic system of the recipient; that there were increases in cholesterol, sphingolipids, and cystine with decreases in sphingomyelinase and glucocerebrosidase activity in tissues of the recipients; and that the recipients survived substantially longer than BALB/c LSD homozygotes and their lifespan was compromised mainly by the secondary effects of irradiation. These lesions, although not as extensive as in homozygous BALB/c LSD, paralleled the lesions which develop in BALB/c LSD. Since the recipient mice were not compromised by the short life span (70 days) of the BALB/c LSD mice, they may be used to study the long-term chronic effects of these metabolic lesions.


Asunto(s)
Trasplante de Médula Ósea , Errores Innatos del Metabolismo/veterinaria , Ratones Endogámicos BALB C , Traumatismos Experimentales por Radiación/terapia , Enfermedades de los Roedores , Animales , Médula Ósea/patología , Ganglios Linfáticos/patología , Errores Innatos del Metabolismo/patología , Ratones , Traumatismos Experimentales por Radiación/patología , Enfermedades de los Roedores/patología , Bazo/patología
4.
Rev Infect Dis ; 6(4): 455-62, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6382552

RESUMEN

The effect of altered lipid A synthesis on the synthesis of major outer membrane proteins was investigated in mutants of Salmonella typhimurium conditionally defective in the synthesis of 3-deoxy-D-mannooctulosonic acid (KDO). The defect is due to a mutation in the structural gene for KDO-8-phosphate synthetase (designated kdsA), and expression of this lesion results in the accumulation of a precursor of lipid A that not only lacks KDO but is also deficient in ester-linked fatty acyl residues. During the initial 20-30 min following a shift of mutants to nonpermissive conditions, the rate of synthesis of the OmpA protein increased approximately 2.5-fold and then decreased. In contrast, the rates of synthesis of total cell-envelope proteins, as well as that of the porin proteins, were unaffected. The mechanism responsible for the initial increase in the rate of OmpA synthesis remains to be established. However, it appears that the subsequent decrease in the rate of OmpA synthesis may be related to a decrease in the stability of OmpA messenger RNA. The effect of nonpermissive conditions on the rate of OmpA synthesis was specifically related to expression of the kdsA lesion, and it was not found to be strain-specific or uniquely related to a single kdsA mutant allele.


Asunto(s)
Proteínas Bacterianas/biosíntesis , Lípido A/biosíntesis , Proteínas de la Membrana/biosíntesis , Salmonella typhimurium/metabolismo , Aldehído-Liasas/genética , Proteínas de la Membrana Bacteriana Externa , Cinética , Mutación , ARN Mensajero/análisis , Salmonella typhimurium/genética
5.
Am J Hum Genet ; 35(4): 621-8, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6881138

RESUMEN

The enzymatic activity of glucocerebrosidase in splenic extracts of the adult nonneurological form of Gaucher disease (type I) was 15% +/- 7% of normal, and the titer of enzyme cross-reacting material (ECRM) in these spleens was 54% +/- 9% of normal. The titer of ECRM in splenic extracts of tissues obtained from patients with the neurological forms of Gaucher disease (types II and III) was essentially the same as in type I Gaucher spleens (59% +/- 10% of normal), but the measurable catalytic activity of glucocerebrosidase in these spleens was substantially lower than that found in type I Gaucher spleens (2.3% +/- 0.6% of normal). Thus, the attentuated glucocerebrosidase activity in spleens from all three forms of Gaucher disease appears to stem from a structurally mutated enzyme that is altered in its catalytic efficiency and possibly in its antigenic expression.


Asunto(s)
Enfermedad de Gaucher/enzimología , Glucosidasas/genética , Glucosilceramidasa/genética , Mutación , Bazo/enzimología , Adolescente , Adulto , Animales , Catálisis , Niño , Reacciones Cruzadas , Femenino , Enfermedad de Gaucher/genética , Glucosilceramidasa/inmunología , Humanos , Sueros Inmunes , Inmunoensayo , Lactante , Masculino , Persona de Mediana Edad , Conejos/inmunología
6.
J Biol Chem ; 258(1): 629-35, 1983 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-6336755

RESUMEN

The effect of altered lipid A synthesis on the synthesis of the OmpA protein was investigated in mutants of Salmonella typhimurium possessing a temperature-sensitive defect in 3-deoxy-D-manno-octulosonate (2-keto-3-deoxyoctonate) synthesis. The defect is due to a mutation in the structural gene for 3-deoxy-D-manno-octulosonate-8-phosphate synthetase (designated kdsA), and expression of this lesion results in the accumulation of an incomplete precursor of lipid A (Rick, P.D., and Osborn, M.J. (1977) J. Biol. Chem. 252, 4895-4903). Pulse labeling studies revealed a pronounced transient increase in the rate of OmpA synthesis following a shift of mutants to nonpermissive conditions. The rate of OmpA synthesis increased about 2.5-fold at 20-30 min following a shift to 42 degrees C and then decreased over the next 30-40 min. A similar but less pronounced increase in the apparent rate of synthesis of the 34-kilodalton porin protein was also observed. In contrast, the rates of synthesis of total cell envelope protein, as well as that of the 35 and 36-kilodalton porin proteins, were relatively unaffected. The effect of increased temperature on the rate of OmpA synthesis was specifically related to expression of the kdsA lesion; it was not found to be strain-specific or uniquely related to expression of a single kdsA mutant allele.


Asunto(s)
Proteínas Bacterianas/biosíntesis , Lípido A/biosíntesis , Lipopolisacáridos/biosíntesis , Proteínas de la Membrana/biosíntesis , Salmonella typhimurium/metabolismo , Proteínas de la Membrana Bacteriana Externa , Membrana Celular/metabolismo , Electroforesis en Gel de Poliacrilamida , Calor , Cinética , Peso Molecular
7.
Biochim Biophys Acta ; 665(3): 615-8, 1981 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-7295755

RESUMEN

Metabolically inert L-[1-14C]glucosylceramide is stored predominantly in the liver after intravenous administration to mice. The half-time of this glycolipid analogue in the liver is 3.5 days and its clearance occurs predominantly via the bile. Within the limited number of Gaucher specimens available for examination very high levels of glucosylceramide were found in the bile of one patient and in the liver of two patients with biliary obstruction. The question of a possible relationship between biliary excretion of glycolipid and the pathogenesis of Gaucher's disease will require further studies.


Asunto(s)
Bilis/análisis , Cerebrósidos/metabolismo , Enfermedad de Gaucher/metabolismo , Glucosilceramidas/metabolismo , Glucolípidos/análisis , Hígado/metabolismo , Animales , Transporte Biológico , Semivida , Humanos , Isomerismo , Cinética , Ratones
8.
Biochim Biophys Acta ; 619(3): 669-79, 1980 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-6257302

RESUMEN

Lipid and lysosomal enzyme levels in the tissues of a strain of mice afflicted with an autosomal rescessive neuroviscereal storage disorder were examined. Sphingomyelinase and glucocerebrosidase activities were consistently diminished in a wide variety of tissues obtained from the affected mice. The activities of these enzymes were clearly attenuated in new-born mice, which at this age, were otherwise indistinguishable from littermates and age-matched controls. The deficiency of sphingomyelinase was more pronounced than glucocerebrosidase. There was progressive accumulation of sphingomyelin, glucocerebroside, lactosylceramide and unesterified cholesterol in the tissues of these mice in the postnatal period. Gangliosides GM2 and GM3 accumulated in the brain of the animals, and GM3 and asialo-GM2 were stored in the liver. Furthermore, there was a large increase in the quantity of hepatic bis(monoacylglycero)phosphate. The accumulation of lipids was parallelled by a progressive elevation in the activity of several lysosomal hydrolases in various tissues. Heterozygous mice were biochemically indistinguishable from normal controls. The phenotypic manifestations in these metabolically mutated animals are compared with those in Niemann-Pick disease and Gaucher's disease in humans.


Asunto(s)
Glucosidasas/deficiencia , Glucosilceramidasa/deficiencia , Errores Innatos del Metabolismo Lipídico/veterinaria , Lisosomas/enzimología , Ratones Endogámicos BALB C/metabolismo , Hidrolasas Diéster Fosfóricas/deficiencia , Esfingomielina Fosfodiesterasa/deficiencia , Animales , Química Encefálica , Gangliósidos/metabolismo , Técnicas In Vitro , Hígado/análisis , Ratones , Mutación , Fosfolípidos/metabolismo , Enfermedades de los Roedores/metabolismo
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