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1.
Water Sci Technol ; 61(12): 3117-28, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20555208

RESUMO

In order to address serious concerns over public health, water scarcity and groundwater pollution in Jordan, the expansion of decentralized wastewater treatment and reuse (DWWT&R) systems to small communities is one of the goals defined by the Jordan government in the "Water Strategy 2009-2022". This paper evaluates the general potential of decentralized wastewater system solutions to be applied in a selected area of the Lower Jordan Rift Valley in Jordan. For the study area, the connection degree to sewer systems was calculated as 67% (5% in the rural sector and 75% in the urban sector). The annual wastewater production available for DWWT&R in the rural sector of the investigation area was calculated to be nearly 3.8 million m(3) at the end of 2007. The future need of wastewater treatment and reuse facilities of the rural sector was estimated to be increasing by 0.11 million m(3) year(-1), with an overall potential of new treatment capacity of nearly 15,500 population equivalents (pe) year(-1). The overall potential for implementing DWWT&R systems in the urban sector was estimated as nearly 25 million m(3) of wastewater in 2007. The future need of wastewater treatment and reuse facilities required for the urban sector was estimated to be increasing at a rate of 0.12 million pe year(-1). Together with the decision makers and the stakeholders, a potential map with three regions has been defined: Region 1 with existing central wastewater infrastructure, Region 2 with already planned central infrastructure and Region 3 with the highest potential for implementing DWWT&R systems.


Assuntos
Eliminação de Resíduos Líquidos/métodos , Demografia , Poluição Ambiental , Previsões , Humanos , Jordânia , Política , Densidade Demográfica , Crescimento Demográfico , Saúde Pública , População Rural , Purificação da Água/métodos , Abastecimento de Água/normas
2.
Science ; 163(3866): 468-9, 1969 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-5762395

RESUMO

Destruction of peripheral sympathetic nerve endings with 6-hydroxydopamine causes a disappearance of cardiac tyrosine hydroxylase, accompanied by a twofold increase in adrenal tyrosine hydroxylase and a small increase in phenyl-ethanolanine-N-methyl transferase. No change in adrenal catecholamine content occurs under these conditions.


Assuntos
Glândulas Suprarrenais/enzimologia , Catecolaminas/farmacologia , Dopamina , Oxigenases de Função Mista/metabolismo , Fenetilaminas/farmacologia , Sistema Nervoso Simpático/efeitos dos fármacos , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/inervação , Animais , Epinefrina/biossíntese , Coração/efeitos dos fármacos , Coração/inervação , Masculino , Miocárdio/enzimologia , Terminações Nervosas/efeitos dos fármacos , Norepinefrina/biossíntese , Ratos , Transferases/metabolismo , Tirosina
3.
Science ; 201(4356): 637-9, 1978 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-675249

RESUMO

Lead (200 milligrams per kilogram) was administered daily by intubation to Long-Evans rats on days 3 through 30 of life. Thirty to 180 days after cessation of lead administration, the lead-treated rats were consistently more polydipsic after lithium administration (2 millimoles per kilogram per day) than were pair-treated controls. Lithium increased the plasma renin activity equally in both the lead treated and the control groups. These data are evidence that there may be permanent neural changes induced by postnatal exposure to lead that are manifested by pharmacological challenge with lithium.


Assuntos
Comportamento de Ingestão de Líquido , Intoxicação por Chumbo/fisiopatologia , Animais , Animais Recém-Nascidos , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Feminino , Lítio/farmacologia , Masculino , Ratos , Renina/sangue
4.
Science ; 207(4430): 535-7, 1980 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-7352264

RESUMO

Biochemical studies have shown that the ability of erythrosine to inhibit dopamine uptake into brain synaptosomal preparations is dependent on the concentration of tissue present in the assay mixture. Thus, the finding that erythrosine inhibits dopamine uptake (which, if true, would provide a plausible explanation of the Feingold hypothesis of childhood hyperactivity) may simply be an artifact that results from nonspecific interactions with brain membranes. In addition, although erythrosine given parenterally (50 milligrams per kilogram) did not alter locomotor activity of control of 6-hydroxydopamine-treated rats, erythrosine (50 to 300 milligrams per kilogram) attenuated the effect of punishment in a "conflict" paradigm.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Dopamina/metabolismo , Corantes de Alimentos/farmacologia , Animais , Transporte Biológico/efeitos dos fármacos , Encéfalo/metabolismo , Hidroxidopaminas/farmacologia , Masculino , Atividade Motora/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Ratos , Sinaptossomos/metabolismo
5.
J Clin Invest ; 78(6): 1648-57, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3537010

RESUMO

The effects of obesity and body fat distribution on splanchnic insulin metabolism and the relationship to peripheral insulin sensitivity were assessed in 6 nonobese and 16 obese premenopausal women. When compared with the nonobese women, obese women had significantly greater prehepatic production and portal vein levels of insulin both basally and following glucose stimulation. This increase correlated with the degree of adiposity but not with waist-to-hip girth ratio (WHR). WHR, however, correlated inversely with the hepatic extraction fraction and directly with the posthepatic delivery of insulin. The latter correlated with the degree of peripheral insulinemia. The decline in hepatic insulin extraction with increasing WHR also correlated with the accompanying diminution in peripheral insulin sensitivity. Increasing adiposity is thus associated with insulin hypersecretion. The pronounced hyperinsulinemia of upper body fat localization, however, is due to an additional defect in hepatic insulin extraction. This defect is closely allied with the decline in peripheral insulin sensitivity.


Assuntos
Tecido Adiposo/anatomia & histologia , Insulina/metabolismo , Obesidade/metabolismo , Vísceras/metabolismo , Adulto , Peptídeo C/metabolismo , Feminino , Glucose/farmacologia , Humanos , Cinética , Fígado/metabolismo
6.
J Clin Invest ; 56(1): 208-17, 1975 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1141432

RESUMO

Studies were undertaken to characterize the renal responses to acute unilateral renal denervation and the mechanisms involved in these responses. Denervation was produced in anesthetized nondiuretic rats by application of phenol to the left renal artery. Studies were also performed in sham-denervated nondiuretic rats. Whole kidney and individual nephron studies were performed before and after denervation or sham denervation. Denervation increased urine volume from the left kidney to about twice its control value (P less than 0.001) and increased urinary sodium excretion from 332 neq min minus -1 to 1,887 neq min minus -1 (P less than 0.001). Glomerular filtration rate (GFR) and renal plasma flow (RPF) remained unchanged in both kidneys after the procedure. The innervated right kidney showed no changes in urine volume or in sodium excretion. After denervation, late proximal ratio of tubular fluid inulin concentration to that of plasma [(F/P)In] decreased from 2.23 to 1.50 (P less than 0.001) while single nephron GFR remained unchanged. Absolute reabsorption decreased from 16.5 to 9.9 n. min minus -1 (P less than 0.001). (F/P)In ratios were also decreased in early distal (from 6.21 to 3.18, P less 0.001) and late distal convolutions (from 16.41 to 8.33, P less than 0.001) during the experimental period. (F/P)Na ratios remained unchanged in the early distal convolutions, but increased from 0.18 to 0.38 (P less than 0.01) in late distal convolutions after denervation. Absolute Na reabsorption after denervation increased in the loop of Henle, distal convolution, and collecting ducts. Any changes in intrarenal hydrostatic pressures after denervation were always small. There were no changes in GFR, RPF, urine volume, urinary sodium excretion, or late proximal (F/P)In after sham denervation. We conclude that the diuresis and natriuresis seen after acute renal denervation were caused by a marked depression of sodium and water reabsorption in the proximal tubule with partial compensation in more distal nephron segments. These responses appeared to be unrelated to systemic or intrarenal hemodynamic changes. The results demonstrate an effect of the renal nerves on proximal tubular function.


Assuntos
Rim/inervação , Ácidos Aminoipúricos , Animais , Pressão Sanguínea , Radioisótopos de Carbono , Denervação , Diurese , Taxa de Filtração Glomerular , Inulina , Rim/irrigação sanguínea , Rim/fisiologia , Túbulos Renais Proximais/inervação , Túbulos Renais Proximais/fisiologia , Masculino , Natriurese , Néfrons/inervação , Néfrons/fisiologia , Fenóis/farmacologia , Pressão , Ratos , Fluxo Sanguíneo Regional , Artéria Renal/efeitos dos fármacos , Trítio , Equilíbrio Hidroeletrolítico
7.
Water Sci Technol ; 56(3): 199-205, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17802856

RESUMO

Constructed wetlands are used for the treatment of wastewater containing metals. In order to clarify the role of plants, flow and the impact of organic matter, an investigation of three factors, each at two different levels, was carried out in small-scale model wetlands. The evaluated factors and levels were: type of flow (subsurface and surface); presence of plants (planted with Typha latifolia and unplanted) and addition of organic matter (with and without). Eight different experimental units were run for a year. The units were fed with synthetic wastewater containing chromium (VI) (1.5 mg L(-1)), zinc (1.5 mg L(-1)), macro, micronutrients and organic matter (to those units in which this factor was being investigated). Subsurface flow wetlands showed a significantly higher rate of chromium removal in comparison with surface flow systems (97 and 60 mg m(-2) d(-1), respectively). Planted systems removed significantly more chromium compared to unplanted systems (85 and 76 mg m(-2) d(-1), respectively), and the addition of organic matter increased the removal rate in a comparison with the units without it (88 and 69 mg m(-2) d(-1), respectively). Similar results were found for zinc; however, the addition of organic matter made no significant difference to zinc removal.


Assuntos
Cromo/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Áreas Alagadas , Zinco/isolamento & purificação , Biodegradação Ambiental , Carbono , Cinética , Projetos Piloto , Plantas , Movimentos da Água
8.
Cancer Res ; 55(13): 2920-6, 1995 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-7540952

RESUMO

The development of drugs that target the tumor neovasculature may hold promise in inhibiting tumor growth. Experiments in vivo with castanospermine, an inhibitor of the glucosidases that convert protein N-linked high mannose carbohydrates to complex oligosaccharides, resulted in significant inhibition of tumor growth in nude mice. Angiogenesis to basic fibroblast growth factor in castanospermine-treated C57/BL mice was similarly reduced. Endothelial cell proliferation, invasion of basement membrane, and differentiation are crucial steps during neovascularization. In vitro differentiation models using Matrigel and postconfluent cultures of endothelial cells were used to study the effects of glycosidase inhibitors on endothelial cell behavior. FACS analysis of cell surface oligosaccharides using either Concanavalin A or L-phytohemagglutinin lectins confirmed an increase in high mannose groups and a decrease in tri- and tetra antennary beta-linked galactose-N-acetylglucosamine on mannose residues of Asn-linked oligosaccharides upon drug treatment. Castanospermine and the glucosidase inhibitor N-methyldeoxynojirimycin prevented the morphological differentiation of endothelial cells in vitro. These compounds did not alter the proliferation of cultured endothelial cells or their ability to attach to various extracellular matrix molecules. However, the cells showed a reduced ability to migrate and to invade basement membrane gels in vitro and an increased tendency to form aggregates that was inhibitable by D-mannose. These studies suggest that certain cell surface oligosaccharides are required for angiogenesis and that glucosidase inhibitors that alter these structures on endothelial cells are able to inhibit tumor growth.


Assuntos
Endotélio/metabolismo , Glicoconjugados/metabolismo , Inibidores de Glicosídeo Hidrolases , Glicosilação/efeitos dos fármacos , Indolizinas/farmacologia , Neoplasias Experimentais/patologia , Neovascularização Patológica , 1-Desoxinojirimicina/análogos & derivados , Animais , Adesão Celular/efeitos dos fármacos , Agregação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Quimiotaxia/efeitos dos fármacos , Glucosamina/análogos & derivados , Glucosamina/farmacologia , Inibidores do Crescimento , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Processamento de Proteína Pós-Traducional/efeitos dos fármacos
9.
Diabetes ; 43(3): 468-77, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8314021

RESUMO

Insulin secretion, clearance dynamics, and their relationship to peripheral plasma insulin and glucose levels were monitored during three 12-h periods of overnight rest, intake of three meals, and continuous enteral feeding of mixed nutrients. The low-frequency ultradian and the high-frequency insulin secretion pulsatility characteristics during the steady-states of overnight rest and continuous enteral feeding were also examined. In abdominally obese subjects, the insulin secretion rate was consistently higher than normal by 2.3-fold. Peripheral plasma insulin levels were increased by 3.4-fold during the overnight period and by 4- to 5-fold during the two fed states. Endogenous insulin clearance was significantly reduced during feeding. Both low- and high-frequency insulin secretory pulsatilities were detected in the abdominally obese subjects. Pulse periods were within the normal range. Pulse maxima, nadirs, and absolute amplitudes were increased concomitant with the increase in insulin secretion. Ultradian relative pulse amplitudes, however, were blunted. A significantly higher pulse-to-pulse variability was observed in the abdominally obese subjects compared with normal subjects. Furthermore, a significantly higher level of interindividual variability in the nutrient-stimulated insulin secretion and in the ultradian pulse characteristics was observed. Thus in abdominal obesity, the increase in pancreatic insulin output is limited and the secretory pulsatilities are aberrant, suggesting a defect in the insulin secretory process. Diminished insulin clearance contributes to the degree of peripheral hyperinsulinemia compensating for the insulin resistance characteristic of this form of obesity.


Assuntos
Insulina/metabolismo , Obesidade/fisiopatologia , Periodicidade , Abdome , Tecido Adiposo , Adulto , Glicemia/metabolismo , Constituição Corporal , Nutrição Enteral , Feminino , Humanos , Insulina/sangue , Secreção de Insulina
10.
J Clin Endocrinol Metab ; 64(1): 162-9, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3536981

RESUMO

The importance of androgenic activity in mediating the effects of obesity and body fat topography on splanchnic insulin metabolism and peripheral insulin sensitivity was studied in 19 nonhirsute premenopausal women with a wide range of ideal body weight [percent ideal body weight (% IBW), 78-202%] and body fat distribution pattern [waist to hip girth ratio (WHR), 0.67-0.91]. Turnover kinetics of peripheral plasma C-peptide and insulin were measured, and estimates of pancreatic insulin production (PIP) and the hepatic extraction fraction (HEF) were calculated. The peripheral insulin sensitivity index (M/I) was determined during an euglycemic insulin clamp study. Androgenic activity was assessed by estimating the plasma level of sex hormone-binding globulin (SHBG) and percentage of free testosterone (% FT). After iv glucose stimulation, PIP ranged from 40-254 mU/min X m2 and correlated highly with % IBW (r = 0.78; P less than 0.01). Insulin HEF ranged from 5-69% of the pancreatic production and was inversely proportional to WHR (r = -0.60; P less than 0.01). Increasing WHR also correlated with the diminution in M/I (r = -0.47; P less than 0.05), which, in turn, correlated with the decline in the HEF of insulin (r = 0.60; P less than 0.01). Since PIP, HEF, and M/I correlated with SHBG and % FT, and since the degree of androgenic activity correlated with % IBW and WHR, partial regression analysis was performed. After adjusting for the effects of SHBG and % FT, the relationship between % IBW and PIP remained unaltered, whereas the correlation between WHR and HEF or M/I and their relationship to each other were either markedly reduced or became insignificant. Thus, in premenopausal women, the increase in pancreatic insulin production with increasing weight is independent of the degree of androgenic activity. On the other hand, the decline in hepatic insulin extraction and diminution in peripheral insulin sensitivity with upper body fat localization are in part mediated by increased androgenic activity. This association may account for the pronounced hyperinsulinemia and insulin resistance characteristic of this form of obesity.


Assuntos
Androgênios/sangue , Glicemia/metabolismo , Insulina/metabolismo , Menopausa , Obesidade/sangue , Circulação Esplâncnica , Tecido Adiposo/metabolismo , Adolescente , Adulto , Fatores Etários , Peso Corporal , Peptídeo C/sangue , Feminino , Humanos , Insulina/sangue , Fígado/metabolismo , Taxa de Depuração Metabólica
11.
J Clin Endocrinol Metab ; 67(4): 760-7, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3047162

RESUMO

The dose-response relationships between portal venous insulin concentrations and hepatic glucose production and between peripheral insulin concentrations and peripheral glucose utilization were determined in 8 nonobese and 17 obese premenopausal women with either upper or lower body fat localization. The glucose production dose-response curves for the two obese groups were shifted to the right at all levels of portal insulinemia. The upper body obese women had a greater rightward shift compared to the lower body obese women. The peripheral glucose utilization dose-response curve was shifted to the right in the lower body obese women, but maximal glucose utilization was normal. The upper body obese women had both a greater rightward shift and a marked reduction in maximal glucose utilization. The insulin concentrations that had half-maximal effects on glucose production and utilization were similar in each group. These results indicate that the liver is not inherently more sensitive to insulin than peripheral tissues. Obesity is associated with a moderate diminution of hepatic and peripheral insulin sensitivity. Upper body fat localization in obese women is characterized by a greater diminution in insulin sensitivity and decline in peripheral insulin responsivity than is lower body fat localization. The marked peripheral insulin resistance in the former group may account for the increased prevalence of glucose intolerance.


Assuntos
Constituição Corporal , Glucose/metabolismo , Obesidade/metabolismo , Adulto , Artérias , Glicemia/metabolismo , Feminino , Glucose/biossíntese , Humanos , Insulina/sangue , Resistência à Insulina , Fígado/metabolismo , Veia Porta
12.
Am J Clin Nutr ; 64(2): 215-21, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8694023

RESUMO

To assess whether fish oil-induced alterations in low-density-lipoprotein (LDL) composition have distinct and important effects on LDL metabolism, we evaluated LDL kinetic behavior in cynomolgus macaques fed an atherogenic diet supplemented with either fish oil (1.6 g n-3 fatty acids; n = 10) or olive oil (n = 9) for > or = 6 mo. LDL from monkeys supplemented with fish oil or olive oil was isolated, labeled with either 125I or 131I, and simultaneously reinjected so that each monkey received its own (autologous injection) and donor (homologous injection) LDL. For LDL injected autologously (monkeys that received their own LDL), the LDL fractional clearance rate (FCR) was reduced in fish oil-supplemented monkeys compared with the olive oil-supplemented controls (0.42 +/- 0.03 compared with 0.56 +/- 0.05 pools/d, P = 0.04). The cholesteryl ester content of fish oil LDL increased compared with olive oil LDL (43 +/- 2% and 36 +/- 3%, respectively, P = 0.03), and the LDL cholesteryl ester content was strongly correlated with autologous LDL clearance (r = -0.76, P = 0.0001). Compared with olive oil LDL, fish oil LDL had a reduced dissociation constant (KD) for binding to the LDL receptor in vitro (KD for fish oil LDL compared with olive oil LDL: 13.9 +/- 1.8 and 7.4 +/- 1.0 mg LDL protein/L, P = 0.03). When both fish oil LDL and olive oil LDL were simultaneously injected into fish oil-supplemented monkeys, the FCR of fish oil LDL was decreased compared with olive oil LDL (0.42 +/- 0.03 and 0.52 +/- 0.04 pools/d, P = 0.006). These data suggest that dietary supplementation with fish oil decreases LDL clearance, and that this effect is mediated, at least in part, by altering LDL structure and reducing the affinity of LDL for its receptor.


Assuntos
Gorduras Insaturadas na Dieta/farmacologia , Óleos de Peixe/farmacologia , Lipoproteínas LDL/sangue , Animais , Células CHO , Colesterol/sangue , Ésteres do Colesterol/análise , Cricetinae , Óleos de Peixe/análise , Óleos de Peixe/metabolismo , Radioisótopos do Iodo , Cinética , Lipoproteínas LDL/análise , Macaca fascicularis , Masculino , Taxa de Depuração Metabólica , Azeite de Oliva , Óleos de Plantas/análise , Óleos de Plantas/metabolismo , Óleos de Plantas/farmacologia , Receptores de LDL/metabolismo , Triglicerídeos/sangue
13.
Neuropsychopharmacology ; 7(2): 95-103, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1418306

RESUMO

The purpose of the present investigation was to explore further the hypothesis that the self-injurious behavior induced by L-dihydroxyphenylalanine (L-DOPA) in neonatal-6-hydroxydopamine (OHDA)-lesioned rats is associated with an action on D1 dopamine receptors. This was accomplished by examining the behavioral responses induced by SKF-38393, quinpirole, and L-DOPA after treatment with the D1 antagonist SCH-23390 and three new pharmacologic agents, SCH-39166, NO-0756, and A-69024, reported to be D1 antagonists. All putative D1 antagonists were found to antagonize the action of SKF-38393 without reducing the increased locomotion and behavioral responses induced by quinpirole, consistent with an in vivo action on D1 receptors. The potency hierarchy of the compounds against the action of SKF-38393 on activity, from strongest to weakest, was: SCH-39166 equaled SCH-23390 and these were greater than NO-0756, which was greater than A-69024. All compounds were found to antagonize L-DOPA-induced self-mutilatory behavior (SMB) in neonatal-6-OHDA-lesioned rats in a dose-related manner. The potency hierarchy against this behavior, from strongest to weakest, was: SCH-23390, SCH-39166, NO-0756, and A-69024. The correlation between the ED50 for the ability of these drugs to antagonize SKF-38393-induced activity and their ability to reduce SMB by L-DOPA was greater than 0.99. In conclusion, the present findings provide additional evidence in vivo that NO-0756, SCH-39166, and A-69024 are selective D1 receptor antagonists.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Animais Recém-Nascidos/fisiologia , Levodopa/farmacologia , Receptores de Dopamina D1/antagonistas & inibidores , Automutilação/psicologia , Simpatectomia Química , Animais , Benzazepinas/farmacologia , Antagonistas de Dopamina , Relação Dose-Resposta a Droga , Ergolinas/farmacologia , Feminino , Atividade Motora/efeitos dos fármacos , Oxidopamina , Papaverina/análogos & derivados , Papaverina/farmacologia , Quimpirol , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D1/efeitos dos fármacos , Tetra-Hidroisoquinolinas
14.
Neuropharmacology ; 36(11-12): 1641-52, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9517435

RESUMO

The relationship between zolpidem sensitivity and GABA(A) receptor alpha subunits was studied in individual dissociated neurons from rat brain. Using whole-cell recording, similar EC50 values were demonstrated for the effect of gamma-aminobutyric acid (GABA) on gated-chloride currents from substantia nigra reticulata (SNR) and lateral septal neurons. Subsequently, many neurons from both the SNR or lateral septum were found to exhibit enhanced GABA-gated chloride currents across concentrations of zolpidem ranging from 10 to 300 nM. Some neurons exhibited a greater than 20% increase in responsiveness to GABA at 30 nM of zolpidem without further increase at higher concentrations of zolpidem. Conversely, zolpidem enhancement of GABA from another group of neurons was not observed at 30 nM zolpidem, but between 100 and 300 nM the response to GABA increased greater than 20%. Finally, a third group of neurons reached both of these criteria for zolpidem enhancement of GABA. This latter spectrum of responses to GABA after varying concentrations of zolpidem was consistent with the presence of either two GABA(A) receptors or a single receptor with differing affinities for zolpidem on an individual neuron. Following determination of the sensitivity of neurons from SNR or lateral septum to zolpidem, cytoplasm was extracted from some individual cells to allow identification of cellular mRNAs for the alpha1, alpha2 and alpha3 GABA(A) receptor subunits with RT-PCR. Those neurons that responded to the 30 nM zolpidem concentration invariably expressed the alpha1-GABA(A) receptor subunit. This result is consistent with the GABA(A) alpha1-receptor subunit being an integral part of a functional high-affinity zolpidem type 1-BZD receptor complex on neurons in brain. Those neurons which showed enhancement of GABA from 100 to 300 nM zolpidem contained mRNAs for the alpha2 and/or the alpha3 receptor subunits, a finding consistent with these alpha subunits forming type 2-BZD receptors. Some individual dissociated SNR neurons were sensitive to both low and high concentrations of zolpidem and contained mRNAs for all three alpha-receptor subunits. These latter individual neurons are proposed to have at least two functional GABA(A) receptor subtypes. Thus, the present investigation emphasizes the importance of characterizing the relationship between endogenous GABA(A) receptor function and the presence of specific structural components forming GABA(A) receptor subtypes on neurons.


Assuntos
Hipnóticos e Sedativos/farmacologia , Neurônios/metabolismo , Piridinas/farmacologia , RNA Mensageiro/biossíntese , Receptores de GABA-A/biossíntese , Receptores de GABA-A/metabolismo , Ácido gama-Aminobutírico/farmacologia , Animais , Primers do DNA , Estimulação Elétrica , Eletrofisiologia , Técnicas In Vitro , Potenciais da Membrana/fisiologia , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp , Reação em Cadeia da Polimerase , Ratos , Ratos Sprague-Dawley , Receptores de GABA-A/efeitos dos fármacos , Substância Negra/citologia , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Zolpidem
15.
J Med Chem ; 31(5): 1052-61, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3361575

RESUMO

A series of 4-(acyloxy)- and 4,4'-bis(acyloxy)benzophenones were synthesized. Some of them, pivalates (trimethylacetates) and isobutyrates in particular, were found to be potent and selective inhibitors of human neutrophil (leukocyte) elastase. A series of 2-[(acyloxy)methyl]-5-(acyloxy)-4-pyrones were synthesized regioselectively from kojic acid. The 4-pyrones bearing a long chain acyl group at the 2-position and either pivaloyloxy or isobutyryloxy at the 5-position were potent and selective inhibitors of the human elastase. A number of analogues and derivatives in both series were synthesized in order to study the structure-activity relationship as summarized in Tables I-VI and in Tables IX and X. The inhibition was selective to human neutrophil elastase. No inhibition of porcine pancreatic elastase or bovine pancreatic chymotrypsin (Tables VII and XI) was observed. The most likely mechanism of inhibition is discussed. The implication of these findings for the treatment of rheumatoid arthritis and emphysema is outlined.


Assuntos
Benzofenonas/síntese química , Elastase Pancreática/antagonistas & inibidores , Piranos/síntese química , Pironas/síntese química , Benzofenonas/farmacologia , Fenômenos Químicos , Química , Humanos , Neutrófilos/enzimologia , Pironas/farmacologia , Relação Estrutura-Atividade
16.
Neuroscience ; 17(1): 99-106, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3960318

RESUMO

Using high resolution autoradiography, the accumulation of radioactivity after intravenous injection of [1-14C]glucose was measured in the corpus callosum, hippocampus, dorsal hippocampal commissure, somatosensory cortex, inferior colliculus and pontine periaqueductal grey. Autoradiograms were prepared by thaw-mounting 4 micron frozen sections on nuclear emulsion-coated slides, and were evaluated quantitatively with a computer-assisted video system for automated counting of silver grains. In all brain regions examined, silver grain densities were greater in rats killed 30 min after injection of [1-14C]glucose compared to rats killed 10 min after injection. After intravenous injection of [1-14C]glucose or 2-deoxy[14C]glucose, the relative uptake and retention of radioactivity in different hippocampal subregions was compared. Striking differences were found in the hippocampus between 2-deoxy[14C]glucose and [1-14C]glucose autoradiograms. After injection of 2-deoxy[14C]glucose, there were large variations in the uptake and retention of radioactivity among different pyramidal cell fields. The CA 3 pyramidal cell field retained considerably more radioactivity than other pyramidal cell fields after injection of 2-deoxy[14C]glucose, while after injection of [1-14C]glucose, the retention of radioactivity was similar in all pyramidal cell fields. After [1-14C]glucose injection, the dentate gyrus contained relatively high levels of radioactivity and more 14C accumulated in the granular layer, compared to the molecular layer. In contrast, after 2-deoxy[14C]glucose injection, there was uniformly less radioactivity throughout the dentate gyrus when compared to rats injected with [1-14C]glucose and there was no preferential accumulation of 2-deoxy[14C]glucose in the granular layer compared to the molecular layer.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Desoxiaçúcares/metabolismo , Desoxiglucose/metabolismo , Glucose/metabolismo , Hipocampo/metabolismo , Animais , Autorradiografia , Corpo Caloso/metabolismo , Colículos Inferiores/metabolismo , Masculino , Substância Cinzenta Periaquedutal/metabolismo , Ratos , Córtex Somatossensorial/metabolismo
17.
Br J Pharmacol ; 52(2): 307-314, 1974 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-4155993

RESUMO

1 Pargyline treatment, 1 h before (+)-amphetamine (1 mg/kg), reduced amphetamine-stimulated motor activity. This inhibition was reversed in animals pretreated with p-chlorophenylalanine (PCPA).2 Following treatment with PCPA or 5,6-dihydroxytryptamine (5,6-DHT), amphetamine-induced locomotor activity was significantly potentiated. The increased response to amphetamine in PCPA-treated rats was reversed in animals pretreated with 5-hydroxytryptophan.3 The inhibition of amphetamine-stimulated locomotor activity by treatment with 6-hydroxydopamine was not reversed by PCPA treatment.4 Stereotypies produced by amphetamine were not found to be altered by depletion of 5-hydroxytryptamine.5 Induction of adrenal tyrosine hydroxylase activity produced by chronic amphetamine administration was significantly potentiated by PCPA, emphasizing the involvement of a 5-hydroxytryptamine inhibitory system in more than one action of amphetamine.


Assuntos
Dextroanfetamina/farmacologia , Serotonina/farmacologia , Glândulas Suprarrenais/enzimologia , Animais , Química Encefálica/efeitos dos fármacos , Indução Enzimática/efeitos dos fármacos , Fenclonina/farmacologia , Humanos , Iproniazida/farmacologia , Masculino , Atividade Motora/efeitos dos fármacos , Pargilina/farmacologia , Ratos , Comportamento Estereotipado/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/metabolismo
18.
Biochem Pharmacol ; 47(6): 1029-37, 1994 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8147901

RESUMO

SC-45662 and SC-41661A, selective arachidonate 5-lipoxygenase (5-LO) inhibitors, had markedly different effects on formyl-methionyl-leucyl-phenylalanine (fMLP) and complement fragment 5a (C5a) induced superoxide release from human neutrophils (PMNs). SC-45662 inhibited superoxide generation induced by fMLP and C5a with IC50 values of 12 and 5 microM, respectively. Furthermore, SC-45662 was capable of inhibiting fMLP and C5a induced superoxide release in PMNs primed with bacterial lipopolysaccharide, tumor necrosis factor-alpha and other priming agents. SC-41661A, a compound from the same chemical series as SC-45662, did not inhibit or induce superoxide generation, but instead primed PMNs for fMLP and C5a induced superoxide generation. The induced superoxide release was concentration dependently enhanced 2 to 4-fold at 5-50 microM. Superoxide release induced by phorbol myristate acetate or serum-activated zymosan was unaffected by either SC-45662 or SC-41661A. The regulation of superoxide generation by these compounds, both of which have the identical oxidation-reduction pharmacophore, was clearly independent of their effects on 5-LO activity. Furthermore, the mechanism by which SC-45662 and SC-41661A alter superoxide generation did not appear to depend on inhibition of xanthine oxidase, catalase or superoxide dismutase. These new compounds provide effective tools for further investigation of the relationship of these two biochemical oxidative systems.


Assuntos
Complemento C5a/farmacologia , Inibidores de Lipoxigenase , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Superóxidos/sangue , Acetatos/farmacologia , Amidas/farmacologia , Animais , Humanos , Inibidores de Lipoxigenase/farmacologia , Neutrófilos/metabolismo , Fenóis/farmacologia , Piridinas/farmacologia , Ratos , Células Tumorais Cultivadas
19.
Mayo Clin Proc ; 75(7): 673-80, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10907381

RESUMO

OBJECTIVE: To determine prospectively the results of Roux-en-Y gastric bypass (RYGB) used as the primary weight-reducing operation in patients with medically complicated ("morbid") obesity. The RYGB procedure combines the advantages of a restrictive physiology (pouch of 10 mL) and a "dumping physiology" for high-energy liquids without requiring an externally reinforced (banded) stoma. PATIENTS AND METHODS: Between April 1987 and December 1998, a total of 191 consecutive patients with morbid obesity (median weight, 138 kg [range, 91-240 kg]; median body mass index, 49 kg/m2 [range, 36-74 kg/m2]), all of whom had directly weight-related morbidity, underwent RYGB and prospective follow-up. RESULTS: Hospital mortality was 0.5% (1/191), and hospital morbidity occurred in 10.5% (20/191). Good long-term weight loss was achieved, and patients adapted well to the required new eating habits. The mean +/- SD weight loss at 1 year after operation (113 patients) was 52 +/- 1 kg or 68% +/- 2% of initial excess body weight. By 3 years postoperatively (74 patients), weight loss was still 66% +/- 2% of excess body weight. Overall, 53 (72%) of 74 patients had achieved and maintained a weight loss of 50% or more of their preoperative excess body weight 3 years after the operation. In addition, only 1 (1%) of 98 patients had persistent postoperative vomiting 1 or more times per week. CONCLUSION: We believe that RYGB is a safe, effective procedure for most patients with morbid obesity and thus may be the current procedure of choice in patients requiring bariatrics++ surgery for morbid obesity.


Assuntos
Anastomose em-Y de Roux , Derivação Gástrica/métodos , Obesidade Mórbida/cirurgia , Adaptação Fisiológica , Adolescente , Adulto , Idoso , Anastomose em-Y de Roux/efeitos adversos , Índice de Massa Corporal , Peso Corporal , Estudos de Avaliação como Assunto , Comportamento Alimentar , Feminino , Seguimentos , Derivação Gástrica/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Complicações Pós-Operatórias , Náusea e Vômito Pós-Operatórios/etiologia , Estudos Prospectivos , Segurança , Taxa de Sobrevida , Resultado do Tratamento , Redução de Peso
20.
Antiviral Res ; 18(3-4): 327-40, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1416911

RESUMO

Mucosal resistance to infection with lactate dehydrogenase-elevating virus (LDV) has been previously demonstrated, and the LDV system presents an important murine model for the study of mucosal barriers to viral infection. In the present study, duodenal molecules were isolated from normal mice which had potent virucidal activity, when tested against LDV as well as canine herpes, canine hepatitis, Semliki forest, and visna viruses. The virucidal activity was demonstrated to be non-immune in nature, and was present in apparently non-enzymatic protein molecules, having a molecular mass of between 10-100 kDa by membrane filtration and 10-17 kDa by gel filtration. The anti-LDV activity of these molecules was suppressed by anti-duodenum antibodies in vitro, and in vivo studies suggested a possible protective role for the anti-viral molecules. We conclude that the normal mouse duodenum contains potent virucidal molecules, which are of interest to the study of biological and molecular mechanisms of viral resistance.


Assuntos
Antivirais/farmacologia , Duodeno/química , Vírus Elevador do Lactato Desidrogenase/efeitos dos fármacos , Extratos de Tecidos/farmacologia , Animais , Feminino , Camundongos , Extratos de Tecidos/química
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