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1.
J Nutr ; 131(10): 2606-18, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11584079

RESUMO

We are studying novel tocotrienols, which have a number of activities that might interfere with the formation of atherosclerotic plaques, including hypocholesterolemic, antioxidant, anti-inflammatory and antiproliferation effects. This study compared the effects of alpha-tocopherol, the tocotrienol-rich fraction (TRF(25)) and didesmethyl tocotrienol (d-P(25)-T3) of rice bran on the pathogenesis of atherosclerotic lesions in C57BL/6 apolipoprotein (apo)E-deficient (-/-) mice. These mice are an excellent model because they become hyperlipidemic even when they consume a low fat diet and they develop complex atherosclerotic lesions similar to those of humans. These compounds were also tested in wild-type C57BL/6 apoE (+/+) and (+/-) mice fed low or high fat diets. When a high fat diet was supplemented with alpha-tocopherol, TRF(25) or d-P(25)-T3 and fed to mice (+/+) for 24 wk, atherosclerotic lesion size was reduced 23% (P = 0.33), 36% (P = 0.14) and 57% (P < 0.02), respectively, and in mice (+/-) fed for 18 wk, lesions were reduced by 19% (P = 0.15), 28% (P < 0.01) and 33% (P < 0.005), respectively, compared with mice fed a control diet. A low fat diet did not cause atherosclerotic lesions in these mice. The low fat diet supplemented with TRF(25) or d-P(25)-T3 fed to apoE-deficient (-/-) mice for 14 wk decreased atherosclerotic lesion size by 42% (P < 0.04) and 47% (P < 0.01), respectively, whereas alpha-tocopherol supplementation resulted in only an 11% (P = 0.62) reduction. These results demonstrate the superior efficacy of tocotrienols compared with alpha-tocopherol. Although tocotrienols decreased serum triglycerides, total and LDL cholesterol levels, the decreases in atherosclerotic lesions seem to be due to the other activities. Serum tocol concentrations in various groups are also described. This is the first report of a significant reduction in the atherosclerotic lesion size in all three genotypes of apoE mice fed a novel tocotrienol (d-P(25)-T3) of rice bran. Dietary tocotrienol supplements may provide a unique approach to promoting cardiovascular health.


Assuntos
Anticolesterolemiantes/uso terapêutico , Apolipoproteínas E/deficiência , Arteriosclerose/prevenção & controle , Gorduras na Dieta/uso terapêutico , Óleos de Plantas/uso terapêutico , Vitamina E/uso terapêutico , Análise de Variância , Animais , Arteriosclerose/patologia , Colesterol/sangue , Cromatografia Líquida de Alta Pressão , Gorduras na Dieta/administração & dosagem , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Óleo de Farelo de Arroz
2.
Alcohol Clin Exp Res ; 24(9): 1456-66, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11003214

RESUMO

BACKGROUND: Evidence that a moderate consumption of alcohol is associated with a reduced incidence of and mortality due to coronary artery disease continues to accumulate. Despite recent evidence that substances in red wine confer resistance to coronary artery disease, it is clear that at least a substantial proportion of the protective effect is due to the alcohol content of the beverage. We have previously shown that the chronic ingestion of alcohol incorporated into a total liquid diet during a 24-week period inhibits the development of fatty streak lesions in hyperlipidemic C57Bl/6 mice. We have now repeated this study and demonstrated that alcohol continues to markedly inhibit atherogenesis during a 48-week period. METHODS: Mice were fed a high fat atherogenic liquid diet with 0% or 6% alcohol or a high fat atherogenic pelleted diet with 0% or 15% alcohol in their drinking water. After 24 and 48 weeks on these diets, subgroups of mice were euthanized and the aortas were studied for extent of atherosclerosis. Plasma lipid levels were also measured and flow cytometry studies performed to characterize their T and B lymphocyte populations. Additional groups of mice were given the high fat atherogenic diets for 24 weeks to allow lesions to develop and were then treated with alcohol diets to determine whether they inhibit the progression of the lesions. RESULTS: The alcohol diets suppressed the development of atherosclerotic lesions at both 24 and 48 weeks in both the liquid and pelleted diet models. The addition of the alcohol diets after allowing lesions to form for 24 weeks halted the further progression of the lesions. The alcohol treatments also decreased the plasma levels of total cholesterol and high density lipoprotein (HDL) cholesterol at almost all time intervals. CONCLUSIONS: We conclude that alcohol not only inhibits the initial development of atherosclerotic lesions but also inhibits the progression of existing atherosclerotic lesions. The alcohol-mediated decrease in HDL cholesterol in these experiments suggests that HDL plays little or no role in amelioration of atherogenesis in this model.


Assuntos
Doenças da Aorta/prevenção & controle , Arteriosclerose/prevenção & controle , Depressores do Sistema Nervoso Central/uso terapêutico , Colesterol/sangue , Etanol/uso terapêutico , Lipoproteínas/sangue , Animais , Doenças da Aorta/sangue , Arteriosclerose/sangue , Dieta Aterogênica , Feminino , Hiperlipidemias/sangue , Camundongos , Camundongos Endogâmicos C57BL
3.
Atherosclerosis ; 149(2): 303-13, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10729380

RESUMO

HMG-CoA reductase inhibitor drugs or 'statins' have been shown to effectively reduce plasma total cholesterol (CHOL), CHOL associated with low-density-lipoprotein (LDL), and triglycerides (TG). In addition, slight elevations in HDL-CHOL are also typically observed. Poloxamer 407 (P-407), a nonionic surfactant, effectively elevates both plasma CHOL and especially TG in a dose-controlled fashion and results in formation of atherosclerotic lesions in the aortas of C57BL/6 mice without the requirement of dietary cholic acid [1,2]. The purpose of the present study was to assess whether a typical statin, namely atorvastatin (Lipitor(R)) would significantly reduce P-407-induced hypercholesterolemia and hypertriglyceridemia as well as cause regression of atherosclerotic lesions resulting from administration of P-407 to C57BL/6 mice. C57BL/6 mice in the present study were treated with either normal saline (C, controls), 0.5 g/kg of P-407 (P), or a high-fat, high-cholesterol, cholate-containing diet (HF) for 120 days. Mice in all groups were then equally and randomly divided and treated with either atorvastatin or saline for an additional 120 days. Beginning at Day 121 and using mice in groups P and HF as an example, one-fourth of the mice in each group received 20 mg/kg per day of atorvastatin with either concomitant HF feeding or P-407 administration ('progression' treatment groups), one-fourth received 20 mg/kg per day of atorvastatin following cessation of HF feeding or P-407 administration, one-fourth received saline (placebo) with either simultaneous HF feeding or P-407 administration ('progression' placebo groups), and one-fourth received saline (placebo) following cessation of HF feeding or P-407 administration. Total plasma CHOL was significantly (P<0.01) lower for mice in groups P and HF when administered atorvastatin relative to saline, but remained significantly (P<0.05) elevated compared to total plasma CHOL of C mice. With discontinuation of either P-407 administration or HF feeding, total plasma CHOL declined rapidly in both P and HF mice with atorvastatin-treated mice generally demonstrating lower plasma CHOL concentrations relative to saline-treated mice. Total plasma TG was significantly (P<0.01) lower for mice in group P administered atorvastatin relative to saline, but remained significantly (P<0.05) elevated compared to plasma TG of C mice. With discontinuation of P-407 administration, total plasma TG declined rapidly in P mice with atorvastatin-treated mice typically demonstrating lower plasma TG concentrations relative to saline-treated P mice. Aortas of mice treated with 20 mg/kg per day of atorvastatin in both groups P and HF, whether maintained on the HF-diet or treated with P-407 from Day 120 to 240 or whether each treatment was terminated at Day 120, revealed no presence of atherosclerotic lesions relative to saline-treated mice and were indistinguishable from aortas retrieved from C mice. Atorvastatin at a dose of 20 mg/kg per day not only significantly reduced the plasma CHOL and TG concentrations, but also resulted in regression of atherosclerotic lesions induced in C57BL/6 mice by administration of P-407 or ingestion of a HF-diet containing cholic acid.


Assuntos
Anticolesterolemiantes/administração & dosagem , Arteriosclerose/tratamento farmacológico , Arteriosclerose/patologia , LDL-Colesterol/sangue , Ácidos Heptanoicos/administração & dosagem , Pirróis/administração & dosagem , Triglicerídeos/sangue , Análise de Variância , Animais , Arteriosclerose/induzido quimicamente , Atorvastatina , Colesterol na Dieta/administração & dosagem , LDL-Colesterol/efeitos dos fármacos , Técnicas de Cultura , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Injeções Intraperitoneais , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Poloxâmero , Valores de Referência , Indução de Remissão
4.
J Cardiovasc Pharmacol ; 34(6): 831-42, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10598127

RESUMO

This study investigated the potential alteration in the amount of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase messenger RNA (mRNA) and lipoprotein lipase (LPL) mRNA in the livers of C57BL/6 mice after long-term (200 days) treatment with the nonionic surfactant called poloxamer 407 (P-407). Previously, P-407 has been used to produce a dose-controlled hyperlipidemic state in C57BL/6 mice with subsequent formation of atherosclerotic lesions. Five groups of mice were studied; controls (C); mice fed a standard chow diet enriched with only cholic acid (CH); mice fed the high-cholesterol, high-fat Paigen diet (HF); mice treated with 0.5 g/kg P-407 every third day (P); and mice administered 0.5 g/kg P-407 every third day while consuming a diet identical to that of mice in group CH (PC). Neither a significant (p < 0.05) weight loss nor alteration in liver enzymes (AST and ALT) were observed for any group throughout the study when compared with the control mice. Total plasma cholesterol (CHOL) was significantly elevated compared with controls for mice in groups HF, P, and PC, whereas total plasma triglycerides (TG) were significantly increased for mice in only groups P and PC. Long-term ingestion of a high-fat diet or a diet enriched in cholic acid resulted in a significant (p < 0.05) reduction in HDL-CHOL when compared with controls. Plasma samples assayed at 200 days for mice in groups HF and P showed a shift in the lipoprotein fraction distribution primarily to VLDL-CHOL as compared with mice in group C in which, as expected, most of the CHOL was contained in the HDL fraction. The biologic activity of HMG-CoA reductase assayed in hepatic microsomal homogenates was significantly reduced for mice in groups CH (p < 0.01), HF (p < 0.01), and PC (p < 0.05), but not for mice in group P, when compared with control. A statistical analysis of the data demonstrated significant (p < 0.05) reductions in the HMG-CoA reductase mRNA levels in hepatic tissue for all treatment groups relative to mRNA levels determined for mice in group C. In contrast, no treatment group demonstrated a significant difference in hepatic LPL mRNA levels when compared with mRNA levels determined for control animals. These data demonstrate that P-407 administration to C57BL/6 mice significantly decreased the amount of HMG-CoA reductase mRNA detected in liver.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Hidroximetilglutaril-CoA Redutases/biossíntese , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Poloxâmero/farmacologia , Tensoativos/farmacologia , Animais , Arteriosclerose/tratamento farmacológico , Peso Corporal/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/patologia , Colesterol/sangue , Dieta , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/toxicidade , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/etiologia , Lipase Lipoproteica/biossíntese , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Poloxâmero/uso terapêutico , Poloxâmero/toxicidade , RNA Mensageiro/biossíntese , Tensoativos/uso terapêutico , Tensoativos/toxicidade , Triglicerídeos/sangue
5.
Atherosclerosis ; 136(1): 115-23, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9544738

RESUMO

Poloxamer 407 (P-407) induces hyperlipidemia in the rat. It was the purpose of this investigation to determine if chronic P-407 administration would produce atherogenic arterial lesions in the C57BL/6 mouse, a strain reported to be susceptible to hyperlipidemia-induced atherosclerotic plaque formation. One injection (i.p.) of P-407 (0.5g/kg) produced hypercholesterolemia in the mouse that peaked at 24 h and returned to control levels by 96 h following treatment. Four groups of mice were maintained: (1) saline injected (C); (2) P-407-injected (0.5g/kg every 3rd day) (P); (3) P-407 injected plus cholic acid in the diet (PC); and (4) mice fed a high cholesterol (CHOL) diet containing cholic acid (HF). Mice from each group were sacrificed following 90, 145, 200, or 300 days of treatment. Plasma lipid concentrations, hepatic CHOL concentrations (145 and 300 day), and aortic atherogenic lesion areas were measured. Plasma CHOL and triglyceride remained at control levels throughout the 300 days in the C group. CHOL of the HF animals plateaued at approximately 225 mg/dl. P-407 produced CHOL concentrations of 600 mg/dl in P mice and 1000-1500 mg/dl in PC animals. There was no lesion formation in C mice. However, by 90 days lesions were present in the three other groups. Size of the lesions progressed through day 300 with the largest lesions (184.33 + 27.99 mu2 x 10(-3)) being present in the PC mice. HF and P animals had lesions of 70.50 + 11.35 and 43.33 + 7.88 mu2 x 10(-3), respectively. This study provides an animal model where atherogenesis has been produced with hyperlipidemia induced using a chemical agent.


Assuntos
Arteriosclerose/etiologia , Hiperlipidemias/induzido quimicamente , Camundongos Endogâmicos C57BL , Poloxaleno/farmacologia , Animais , Aorta/patologia , Arteriosclerose/patologia , Colesterol/sangue , Colesterol na Dieta/farmacologia , Feminino , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Poloxaleno/administração & dosagem , Ratos , Triglicerídeos/sangue
6.
Med Sci Sports Exerc ; 29(11): 1416-21, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9372476

RESUMO

We are attempting to develop a chemically-induced murine model for the study of atherosclerosis. Injection of poloxamer-407 (P-407) into rats and mice causes significant dose-dependent hypercholesterolemia and hypertriglyglyceridemia. The elevated triglycerides (TG) seem to result primarily from the compound's inhibition of lipoprotein lipase. P-407 also indirectly stimulates the activity of the rate limiting enzyme in cholesterol (CHOL) biosynthesis, HMG CoA reductase. In addition, P-407 promotes changes in the concentration of hepatic CHOL content. These date indicate that the hyper CHOL could be the result of increased CHOL synthesis, as well as a clearing of CHOL from the liver. Chronic injection into mice of P-407 for 145 d produced atherogenic lesions in the aortas of C57BL/6 mice. The response was equivalent to that seen in animals eating a high CHOL diet for 145 d. Cholic acid potentiated the P-407-induced atherogenesis. These data suggest that P-407 could be used as an agent for the study of hyperlipidemia-induced atherogenesis.


Assuntos
Arteriosclerose/induzido quimicamente , Modelos Animais de Doenças , Hiperlipidemias/induzido quimicamente , Poloxaleno , Animais , Colesterol/metabolismo , Dieta , Relação Dose-Resposta a Droga , Injeções Intravenosas , Camundongos , Camundongos Endogâmicos C57BL , Ratos
7.
Am J Pathol ; 149(2): 675-85, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8702005

RESUMO

T lymphocytes and monocyte/macrophages are prominent components of atherosclerotic lesions, and many of these cells are activated and secreting cytokines. To determine the role of these cells in the pathogenesis of atherosclerosis, we studied its development in T-cell-deficient mice fed a high fat atherogenic diet. Depleting euthymic mice of their CD4+ lymphocytes by 20 weekly injections of CD4 monoclonal antibodies reduced the mean area of their aortic lesions by approximately 70%. Similarly, the mean lesion area of T-cell-deficient nude (nu/nu) mice was 10% of the size of that of their heterozygote (nu/+) litter mates. Flow cytometric studies of splenic T cells and analyses of serum total and HDL cholesterol of these mice indicated that the differences in mean lesion areas among the experimental groups were most closely correlated with differences in splenic T cells content. These studies suggest that in these two models T lymphocytes contribute to the pathogenesis of early atherosclerotic lesions and that a further understanding of this phenomenon may provide future approaches toward the prevention and treatment of the disease.


Assuntos
Arteriosclerose/imunologia , Linfócitos T CD4-Positivos/imunologia , Hiperlipidemias/complicações , Animais , Anticorpos Monoclonais/farmacologia , Aorta/efeitos dos fármacos , Aorta/patologia , Arteriosclerose/patologia , Arteriosclerose/prevenção & controle , Linfócitos T CD4-Positivos/patologia , Morte Celular/imunologia , Colesterol/sangue , HDL-Colesterol/sangue , Citotoxicidade Imunológica , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Nus , Triglicerídeos/sangue
8.
Am J Pathol ; 147(6): 1749-58, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7495299

RESUMO

Although there is abundant clinical evidence that the consumption of alcohol (ethanol) in moderate amounts has a protective effect on coronary artery disease, the mechanism of this effect is not understood. The prevailing theory supported by a limited number of clinical and experimental animal studies indicates that the ability of alcohol to elevate serum high-density lipoprotein cholesterol levels is an important mechanism. Although there have been a large number of studies on the effects of alcohol on serum lipoprotein and apolipoproteins on coronary artery disease, there have been very few that have, at the same time, looked directly and systematically at its effects on the histopathological development of atherosclerotic lesions. In the following studies we employed the hyperlipidemic C57BL/6 female mouse model and formulated an all liquid high fat atherogenic diet to provide the mice with the 3% or 6% alcohol. After 22 weeks on this diet, alcohol markedly inhibited the development of fatty streak atherosclerotic lesions in a dose-dependent fashion. Surprisingly, there was a dose-dependent decrease in plasma high-density lipoprotein cholesterol values, which suggests that high-density lipoprotein alterations play little or no role in the amelioration of atherosclerosis in this model.


Assuntos
Arteriosclerose/prevenção & controle , HDL-Colesterol/sangue , Etanol/administração & dosagem , Hiperlipidemias/complicações , Animais , Arteriosclerose/patologia , Colesterol/sangue , Gorduras na Dieta , Etanol/sangue , Feminino , Lipoproteínas/sangue , Fígado/enzimologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL
9.
Am J Pathol ; 142(6): 1906-15, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8506958

RESUMO

We and others have demonstrated that T lymphocytes are prominent components of atherosclerotic lesions. We hypothesized that if T cells were necessary for the development of atherosclerosis it would be possible to demonstrate its prevention or retardation in T-cell-suppressed mice. To test this hypothesis, CyA, a potent suppressor of T-cell activation, was used to treat C57BL/6 mice undergoing lipid hyperalimentation. Mice receiving normal mouse chow were completely free of atherosclerotic lesions. In mice receiving the atherogenic diet plus control oil injections, lesions of the aorta and coronary arteries were observed at 135 days and increased progressively in area until 310 days. Somewhat surprisingly, mice given the atherogenic diet plus CyA injections displayed even larger lesions at all three observed time intervals. Although CyA did suppress T-cell reactivity sufficiently to obtain the expected prolongation of skin allografts, it did not suppress the development or progression of atherosclerotic lesions.


Assuntos
Arteriosclerose/etiologia , Ciclosporina/farmacologia , Hiperlipidemias/complicações , Animais , Aorta/metabolismo , Aorta/patologia , Arteriosclerose/patologia , Arteriosclerose/fisiopatologia , Artérias Carótidas/metabolismo , Artérias Carótidas/patologia , Colesterol/sangue , Ciclosporina/administração & dosagem , Ciclosporina/efeitos adversos , Dieta Aterogênica , Feminino , Hiperlipidemias/sangue , Hiperlipidemias/patologia , Injeções Subcutâneas , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Lipoproteínas VLDL/sangue , Fígado/química , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transplante de Pele/patologia , Fatores de Tempo , Transplante Homólogo
10.
Am J Pathol ; 130(2): 369-76, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3257650

RESUMO

In order to investigate the role of mononuclear cells in infiltrates during the initial stages of atherogenesis, the authors have studied by immunohistochemical methods the aortas and coronary vessels of children and young adults (ages 15-34) dying of acute trauma. Eccentric intimal thickening often accompanied by intimal mononuclear cell infiltration was commonly observed in sections of the lower thoracic aorta. These changes were usually related to intercostal branching sites and thus greater in the dorsal (posterior) than on the ventral aspect of the aorta in 64 of 75 cases examined. In some of these samples the authors were able to demonstrate the presence of T lymphocytes and monocyte-macrophages (mono/macs) by the use of the monoclonal antibodies T11 and Leu-M5, respectively. Many of the T lymphocytes were T8-positive and thus of the cytotoxic/suppressor subtype. T4-positive cells of the inducer/helper subtype were seen occasionally. T cells of both T4 and T8 subsets and mono/macs were also demonstrated in areas of eccentric intimal thickening in coronary arteries and in raised coronary lesions. In both the aortas and the coronary lesions the T cells and mono/macs were often closely associated with one another. This finding is of interest in view of the well-known cell-regulatory and cytotoxic potential of these cells. Extrapolating from findings in non-human primates, the authors suggest a potential role for mononuclear cells in human atherogenesis.


Assuntos
Aorta/patologia , Arteriosclerose/patologia , Vasos Coronários/patologia , Linfócitos T/patologia , Adolescente , Adulto , Anticorpos Monoclonais , Antígenos de Diferenciação de Linfócitos T/análise , Aorta/citologia , Artérias/citologia , Artérias/patologia , Criança , Vasos Coronários/citologia , Células Espumosas/citologia , Células Espumosas/imunologia , Células Espumosas/patologia , Humanos , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/patologia , Monócitos/citologia , Monócitos/imunologia , Monócitos/patologia , Linfócitos T/citologia , Linfócitos T/imunologia
11.
Ann Intern Med ; 108(2): 175-80, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3124680

RESUMO

Infection with human immunodeficiency virus (HIV) may cause viral antigenemia, detected primarily as p24 viral core protein. Among 16 patients with the acquired immunodeficiency syndrome (AIDS) or AIDS-related complex studied serially, 12 had or developed antigenemia ranging from 16 to 3006 pg/mL in plasma. The level could be categorized as high (greater than 100 pg/mL) or low (15 to 65 pg/mL). Three patients with anti-p24 antibody had no antigenemia. Zidovudine (AZT), 200 or 250 mg every 4 hours, reduced antigenemia by about 90%; other regimens were less effective. Leukocyte cultures were positive for HIV from patients with antigenemia, and in one third of samples in the absence of antigenemia. High levels of antigenemia correlated with symptoms, CD4 cell count, and prognosis. Drug toxicity requiring a lower dose was followed by increased antigenemia, recurrent symptoms, and decreased CD4 cells, suggesting lymphocyte toxicity. Monitoring antigenemia can be useful in evaluating patients with HIV infection and in evaluating the effect of antiviral chemotherapy.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Antígenos Virais/análise , Antivirais/uso terapêutico , HIV/imunologia , Timidina/análogos & derivados , Complexo Relacionado com a AIDS/tratamento farmacológico , Complexo Relacionado com a AIDS/imunologia , Complexo Relacionado com a AIDS/microbiologia , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/microbiologia , Antivirais/efeitos adversos , Ensaios Clínicos como Assunto , Método Duplo-Cego , Antígenos HIV , Proteína do Núcleo p24 do HIV , Humanos , Linfócitos/classificação , Proteínas dos Retroviridae/análise , Timidina/efeitos adversos , Timidina/uso terapêutico , Zidovudina
12.
J Immunol ; 139(2): 332-7, 1987 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-2955037

RESUMO

Alloreactivity of intragraft and peripheral blood lymphocytes from tolerant canine lung allograft recipients was examined. Tolerance was induced by variable periods of treatment with cyclosporine. Analysis of effector cells from lung allografts (obtained by bronchoalveolar lavage) revealed the absence of specific cytolytic T lymphocyte (CTL) activity and the presence of a low level of cytolytic activity detected in a lectin-dependent cell-mediated cytotoxicity assay. In contrast, high levels of specific CTL activity and lectin-dependent activity were detected in cell preparations from lung allografts undergoing rejection. Tolerant recipients retained normal ability to generate specific CTL activity to third party alloantigens in mixed lymphocyte cultures (MLC) but had diminished ability to generate CTL to donor alloantigens in recipient X donor MLC. Addition of exogenous interleukin 2 to these MLC was unable to restore donor-specific CTL activity. Lymphocytes from tolerant recipients were, however, capable of generating proliferative responses and lectin-dependent cytotoxicity on exposure to donor alloantigens in MLC. Evidence presented in this report suggests that the lectin-dependent cytolytic activity generated in these MLC is mediated by lymphokine-activated killer cells. Such cells are likely to be activated by interleukin 2 released in the proliferative response. The results support the proposal that the cyclosporine-induced tolerant state is characterized by the relative inability to respond against major histocompatibility complex class I antigens in contrast to class II antigens and/or minor histocompatibility antigens since MLC-induced CTL are directed, for the most part, against class I molecules.


Assuntos
Ciclosporinas/farmacologia , Citotoxicidade Imunológica/efeitos dos fármacos , Terapia de Imunossupressão , Ativação Linfocitária/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Animais , Cães , Sobrevivência de Enxerto , Tolerância Imunológica , Interleucina-2/farmacologia , Transplante de Pulmão , Teste de Cultura Mista de Linfócitos , Linfócitos T Citotóxicos/efeitos dos fármacos
13.
Am J Drug Alcohol Abuse ; 13(4): 401-12, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2961253

RESUMO

We screened inpatient and outpatient parenteral drug users with no clinical evidence of AIDS for immunodeficiency and antibodies to HTLV-III by ELISA. Among 20 outpatient drug users, 5 (25%) were seropositive. Three of these (and 2 who were seronegative) had low T-cell ratios. Over 6 months, 1 seropositive patient with a low ratio developed oral thrush and weight loss. We also studied 13 parenteral drug users hospitalized for conditions other than AIDS. Eight had low T-cell ratios, and at least 6 of these developed AIDS or ARC within 4 months. Serum from 8 of 13 inpatients was available for HTLV-III testing: 6/8 were seropositive and 3 of these 6 were among those developing AIDS or ARC. Abnormal T-cell ratios among all patients were associated with abnormal HTLV-III serology (p = .02). Of the 7 patients who developed AIDS or ARC, 4 were tested for both antibodies and T-cell ratios: all 4 were seropositive and had low ratios. A low ratio (p = .0004), a positive ELISA (p = .014), and abnormalities of both tests (p = .001) were associated with the development of AIDS or ARC. Of the 26 patients without AIDS or ARC, 3 were lost to follow-up and 23 did not develop AIDS or ARC. Six of these 26 had abnormal ratios. Of the 21 patients who did not develop AIDS or ARC and who were tested for HTLV antibodies, 2 were lost to follow-up. Seven of 21 were seropositive and 2/21 were both seropositive and had a low ratio. One of these 2 seropositive patients with low ratios also had lymphadenopathy, but he was lost to follow-up. The other had no adenopathy and remained well until her death from trauma a year later. This study found two populations with very different risks. Six of 13 hospitalized parenteral drug users and only 1 of 20 healthy outpatients developed AIDS or ARC.


Assuntos
Transtornos Relacionados ao Uso de Opioides/sangue , Síndrome da Imunodeficiência Adquirida/transmissão , Adulto , Linfócitos B/imunologia , Feminino , Soropositividade para HIV/sangue , Soropositividade para HIV/imunologia , Humanos , Injeções Intravenosas , Masculino , Metadona/uso terapêutico , Transtornos Relacionados ao Uso de Opioides/imunologia , Transtornos Relacionados ao Uso de Opioides/reabilitação , Linfócitos T/imunologia , Linfócitos T Auxiliares-Indutores/imunologia
14.
Transplantation ; 42(5): 466-72, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3538531

RESUMO

Although cyclosporine (CsA) is widely used as the primary agent for inhibiting the rejection of organ allografts in man, the ideal immunosuppressive regimen for utilizing this drug is still uncertain. To investigate this question, a concanavalin A (con A)-dependent cell-mediated cytotoxicity (CDCMC) assay was used to examine the development of intragraft and peripheral blood cytolytic T lymphocyte activity during CsA dose tapering. These studies were conducted in a canine single-lung transplantation model that facilitates serial examination of intragraft effector cells by bronchoalveolar lavage (BAL). A remarkable correlation of increased intragraft CDCMC and clinical evidence of lung allograft rejection was observed during CsA dose tapering in some recipients. In other recipients CDCMC remained low and evidence of rejection was not observed during drug tapering. In contrast, peripheral blood CDCMC did not correlate well with evidence of rejection. Rejection phenomena observed after termination of CsA therapy were reversed by resumption of CsA treatment but were not reversed by administration of methylprednisolone. Furthermore, the increased level of CDCMC was diminished by reinstitution of CsA therapy at the initial dosage. Following termination of CsA therapy, a prolonged period of unresponsiveness was observed in nearly two-thirds of the recipients, and 60% of these latter dogs had unlimited survival of their lung allografts (median greater than 496 days). Intragraft CDCMC remained low during the periods of unresponsiveness and increased upon onset of rejection. We conclude that measurement of intragraft CDCMC is a useful in vitro method of monitoring lung allograft rejection, and therefore provides a technique for adjusting CsA dosage schedules to achieve maximally effective immunosuppression. The use of this assay for monitoring rejection of other organ grafts requires further investigation.


Assuntos
Concanavalina A/farmacologia , Ciclosporinas/farmacologia , Citotoxicidade Imunológica/efeitos dos fármacos , Rejeição de Enxerto/efeitos dos fármacos , Transplante de Pulmão , Animais , Cães , Sobrevivência de Enxerto/efeitos dos fármacos , Pulmão/imunologia , Masculino , Ratos , Linfócitos T Citotóxicos/imunologia , Irrigação Terapêutica , Transplante Homólogo
15.
Ann Ophthalmol ; 18(5): 186-7, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-3755017

RESUMO

Sarcoidosis, a granulomatous disease first recognized as a dermatologic disorder, is now known to involve multiple organs, including the eye. Indeed, ocular involvement may be the only clinical manifestation of this protean disease; it may involve any part of the visual apparatus and its adnexal structures. In this paper we report on the concurrence of sarcoidosis of the lid with Graves' ophthalmopathy in the same patient.


Assuntos
Oftalmopatias/complicações , Doença de Graves/complicações , Sarcoidose/complicações , Feminino , Humanos , Pessoa de Meia-Idade
16.
Transplantation ; 40(2): 143-6, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3895618

RESUMO

Bronchial anastomotic healing was evaluated in 22 long-term-surviving canine lung allotransplant recipients treated with cyclosporine as the major immunosuppressive agent. Mean survival in these dogs was over 155 days, and 4 animals survived 1-3 years. Bronchial anastomotic complications were limited to 5 cases of minimal (less than 15%) bronchostenosis. The bronchial anastomoses became somewhat edematous and friable during rejection episodes, but no clinically serious sequelae--such as hemorrhage, peribronchial abscess, or bronchial dehiscence--were observed. Gross and microscopic evaluation of the recipient and donor segments of the anastomoses revealed excellent healing, with only scattered areas of inflammatory cells. The decreased frequency and severity of rejection episodes in animals treated with cyclosporine permits early revascularization of the bronchus to take place and reduces the need for other immunosuppressive agents that may interfere with bronchial healing. Cyclosporine is an effective immunosuppressive agent for canine lung allotransplantation and allows normal bronchial anastomotic healing to occur.


Assuntos
Brônquios/cirurgia , Ciclosporinas/toxicidade , Transplante de Pulmão , Cicatrização/efeitos dos fármacos , Animais , Brônquios/efeitos dos fármacos , Brônquios/patologia , Cães , Transplante Homólogo
17.
J Thorac Cardiovasc Surg ; 87(3): 439-44, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6700250

RESUMO

In order to assess the effect of revascularization on the healing of bronchial anastomoses in a canine model, we developed a microsurgical technique that permits the immediate reperfusion of the distal bronchial segment by a direct anastomosis of the bronchial artery to an intercostal artery. This technique was applied to dogs that underwent hilar stripping and bronchial transection and reanastomosis, and it prevented the development of ischemic bronchial damage. In addition, several groups of dogs that had undergone bronchial transection and reanastomosis and, in some cases, reestablishment of bronchial arterial circulation, were treated with 40 mg of prednisone daily for periods of 7 and 21 days. The animals treated with corticosteroids demonstrated a lesser degree of inflammatory damage to the bronchial anastomotic site than similar groups of untreated animals. These findings support the hypothesis that restoration of bronchial arterial blood flow at the time of lung transplantation can reduce anastomotic damage to the distal or donor bronchial component. Our results further suggest that corticosteroid therapy alone does not increase bronchial anastomotic damage, and, in fact, may reduce inflammation at the bronchial anastomotic site.


Assuntos
Artérias Brônquicas/cirurgia , Pulmão/cirurgia , Prednisona/uso terapêutico , Circulação Pulmonar , Cicatrização/efeitos dos fármacos , Animais , Cães
18.
Cancer ; 53(2): 267-71, 1984 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-6360336

RESUMO

Ferritins, a group of isomeric proteins that have important functions in iron metabolism and storage, have been demonstrated to be carcinoembryonic antigens. It has been recently shown that a subpopulation of lymphocytes from the peripheral blood of patients with Hodgkin's disease or breast cancer bear ferritin on their surface membranes. In view of the potential diagnostic and prognostic value of ascertaining the number of ferritin-bearing lymphocytes, the authors developed a simple indirect immunofluorescent technique for identifying them and used this technique to examine the peripheral blood lymphocytes of 44 patients with carcinomas of the head and neck (26), colon (14), and lung (4). It was found that patients with cancer had a mean percentage of 10% ferritin-bearing lymphocytes in their peripheral blood as compared with 3.1% in controls. Ferritin binding did not appear to be influenced by a cell's capacity to form sheep erythrocyte (E) rosettes since no correlation could be found between the percentages of lymphocytes bearing ferritin and those forming three different varieties of E-rosettes. There appeared to be no correlation of the percentages of ferritin-bearing lymphocytes with clinical staging except for a small, but significant (P less than 0.05), increase in the number of patients with head and neck cancer and nodal metastases. Although the functional significance of ferritin-bearing lymphocytes is currently unknown, the appearance of this subpopulation of cells in the blood appears to be associated with cancer. This assay may prove to be useful as a diagnostic tool, as a prognostic tool, or as a means of identifying patients at a risk for developing cancer and, therefore, it deserves further exploration.


Assuntos
Neoplasias do Colo/sangue , Ferritinas/análise , Neoplasias de Cabeça e Pescoço/sangue , Neoplasias Pulmonares/sangue , Linfócitos T/metabolismo , Contagem de Células , Membrana Celular/imunologia , Membrana Celular/metabolismo , Feminino , Imunofluorescência , Humanos , Metástase Linfática , Masculino , Probabilidade , Formação de Roseta , Linfócitos T/imunologia
19.
J Thorac Cardiovasc Surg ; 86(4): 537-42, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6353076

RESUMO

Cyclosporin, a potent new immunosuppressive agent, was used (alone or in combination with other drugs) in 28 canine single lung allograft recipients. Mean recipient survival with good allograft function was 155 days with cyclosporin and far exceeded that obtained in previous single lung allograft recipients treated with standard immunosuppression (15 to 22 days). The results of these experiments were as follows: (1) 20% of the recipient animals exhibited no evidence of rejection whatsoever; (2) four of 28 animals survived more than 350 days with good allograft function; (3) 79% of the animals exhibited some evidence of rejection that was easily reversed in 74% of instances with corticosteroids; (4) 10 of 28 animals exhibited good lung allograft function 5 months or more after operation; (5) in cyclosporin-treated lung allograft recipients, rejection was diagnosed by the presence of infiltrate on chest roentgenogram, analysis of the cellular content of bronchoalveolar lavage samples, and decreased perfusion on 99mtechnetium lung scan; (6) complete healing without stenosis of the bronchial anastomosis occurred in 82% of the animals studied. One of two patients treated with cyclosporin after undergoing single lung allografting survived 7 weeks after transplantation and 4 weeks after contralateral pneumonectomy. Episodes of rejection were reversible, and the bronchial anastomosis healed normally. This overall experience indicates that cyclosporin, although not a perfect immunosuppressive agent, increases the likelihood of success with therapeutic single lung transplantation.


Assuntos
Ciclosporinas/uso terapêutico , Imunossupressores/uso terapêutico , Transplante de Pulmão , Adulto , Idoso , Animais , Ciclosporinas/administração & dosagem , Cães , Rejeição de Enxerto/efeitos dos fármacos , Humanos , Imunossupressores/administração & dosagem , Masculino , Transplante Homólogo/mortalidade
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