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1.
J Natl Cancer Inst ; 68(3): 381-3, 1982 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6278192

RESUMO

Prolactin-binding sites were determined in 759 human breast tumor biopsy specimens. Ovine prolactin (oPRL) was used in the binding assay of 569 tumors with 13% of the tumors showing a positive content with more than 1% specific binding. Human prolactin (hPRL) was utilized for 343 tumors with 36% of the tumors binding 1% or greater of the added radioactivity. When human growth hormone (hGH) was used as the labeled ligand in 95 tumors, only 2% of the tumors specifically bound more than 1% of the hGH. A total of 153 tumors were assayed simultaneously with the use of labeled hPRL and oPRL. Whereas 10.4% of the tumors showed the presence of prolactin-binding sites (greater than 1% specific binding) when oPRL was used, an approximately threefold increase (29.4%) in tumors possessing prolactin receptors was revealed when hPRL was used as the labeled ligand. Therefore, hPRL is the preferred ligand for the assessment of prolactin receptor levels in human breast cancer biopsy specimens.


Assuntos
Neoplasias da Mama/metabolismo , Receptores de Superfície Celular/análise , Biópsia , Neoplasias da Mama/patologia , Hormônio do Crescimento/análise , Humanos , Ligantes , Receptores da Prolactina
2.
J Natl Cancer Inst ; 66(1): 97-102, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6779043

RESUMO

Noninbred Sprague-Dawley rats bearing N-methyl-N-nitrosourea (MNU)-induced mammary tumors were ovariectomized at 2.5, 3.5, and 4.5 months after the first MNU injection to determine the response to castration as a function of the time of tumor appearance. Tumor number and tumor size recorded at weekly intervals revealed that the tumors in the control rats continued to grow during each of the three observation periods, but that tumor growth was significantly less during the third period. Ovariectomy performed at 2.5 months after the first MNU injection produced a stabilization of tumor number; when performed at 3.5 or 4.5 months, it resulted in a slight decline in tumor number. Although tumor size decreased slightly in rats that were ovariectomized at 2.5 months, many of the tumors regrew during the last 2 weeks of observation. This was not true, however, for rats that were ovariectomized at either 3.5 or 4.5 months after the first MNU injection. The level of receptors for 17 beta-estradiol (E2), progesterone, and prolactin were significantly reduced by ovariectomy. E2 receptors, which ranged from 2.04 +/- 18 to 2.24 +/- 0.24 (mean +/- SEM) pmol/g tissue for the first and second groups of control rats, declined to 0.93 +/- 0.14 pmol/g tissue for the ovariectomized rats at the end of the last interval studied (5.5 mo after the first MNU injection). This study suggests that hormone responsiveness (response to ovariectomy) of MNU-induced mammary tumors increases slightly with the age or time of appearance of the tumors.


Assuntos
Castração , Neoplasias Mamárias Experimentais/induzido quimicamente , Metilnitrosoureia , Compostos de Nitrosoureia , Animais , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Neoplasias Hormônio-Dependentes/induzido quimicamente , Neoplasias Hormônio-Dependentes/metabolismo , Neoplasias Hormônio-Dependentes/patologia , Prolactina/sangue , Ratos , Receptores de Estrogênio/análise , Fatores de Tempo
3.
Diabetes ; 24(7): 658-63, 1975 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1098947

RESUMO

Isolated islets of Langerhans from adult male rats were cultured in media containing either basal (1 gm./ml.) or high glucose (3 mg./ml.), and the media were changed every two days for fourteen days. The insulin released in each medium was measured by a back-titration radioimmunoassay. Insulin secretion was fairly constant in the basal glucose medium and a consistent three-to-sevenfold increase was observed in the alternated or continuous presence of high glucose. Addition of an excess of anti-insulin serum did not change significantly the basal or stimulated release of insulin. The electron microscopic appearance of the islets after fourteen days of incubation showed well-preserved islets both with or without anti-insulin serum. Anti-insulin serum did not alter the ultrastructural aspects of the islets in either basal or high glucose media.


Assuntos
Glucose/farmacologia , Anticorpos Anti-Insulina/administração & dosagem , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Animais , Relação Dose-Resposta a Droga , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Técnicas de Cultura de Órgãos , Ratos
4.
Hypertension ; 26(3): 503-8, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7649589

RESUMO

A noninvasive technique has been developed and validated for calculating capacitive and oscillatory systemic arterial compliance with the use of pulse wave analysis and a modified Windkessel model. Application of the technique to subjects with hypertension, postmenopausal women with symptomatic coronary artery disease, and appropriate control subjects has confirmed a reduction of oscillatory compliance in the disease states and an increase in capacitive and oscillatory compliances in response to vasodilator drugs. This method should be useful in screening subjects for early evidence of vascular disease and in monitoring the response to therapy.


Assuntos
Doenças Vasculares/diagnóstico , Pressão Sanguínea , Débito Cardíaco , Complacência (Medida de Distensibilidade) , Doença das Coronárias/diagnóstico , Doença das Coronárias/fisiopatologia , Feminino , Humanos , Hipertensão/fisiopatologia , Masculino , Artéria Radial/fisiopatologia , Reprodutibilidade dos Testes
5.
Am J Clin Nutr ; 53(1): 126-31, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1984337

RESUMO

Plasma zinc, iron, copper, and selenium and selected blood proteins were measured in 66 men before (BHW) and after (AHW) a 5-d period of sustained physical and psychological stress called Hell Week. Recovery blood samples were obtained from 26 men 7 d after Hell Week. Dietary intakes were determined BHW and during Hell Week; zinc, iron, copper, and selenium intakes during Hell Week averaged 23.6 +/- 3.4 mg/d, 35.4 +/- 3.9 mg/d, 3.0 +/- 0.5 mg/d, and 92.5 +/- 26.7 micrograms/d, respectively. C-reactive protein was detected in only five subjects BHW and in all subjects AHW. Zinc, iron, selenium, and albumin decreased by 33%, 44%, 12%, and 9%, respectively, whereas ferritin, ceruloplasmin, and creatine kinase concentrations increased AHW by 59%, 8%, and 266%, respectively. Haptoglobin concentrations increased 57% in 30 subjects but decreased 32% in 23 subjects AHW. The biochemical changes were transitory because protein (except ferritin) and mineral concentrations were similar to BHW values 7 d after Hell Week. Hell Week induced changes characteristic of an acute-phase response in physically active men.


Assuntos
Educação Física e Treinamento , Estresse Psicológico/metabolismo , Oligoelementos/metabolismo , Análise de Variância , Proteínas Sanguíneas/metabolismo , Ingestão de Alimentos , Humanos , Masculino , Estresse Psicológico/sangue , Estresse Psicológico/urina , Fatores de Tempo
6.
Am J Med ; 102(3): 227-31, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9217589

RESUMO

PURPOSE: Consistent changes in the arterial pulse contour are found with aging and disease states that impair the compliance characteristics of blood vessels that buffer pulsatile phenomena in the arterial tree. We assessed whether vascular adaptation in structure or tone of blood vessels associated with long-term cigarette smoking would influence steady state or pulsatile hemodynamics at a preclinical stage. PATIENTS AND METHODS: We analyzed intraarterial brachial artery waveforms in 35 healthy long-term cigarette smokers and 32 nonsmoking control subjects matched for age and gender. The diastolic pressure decay was segmented into two components: an exponential decay that reflects the compliance characteristics of the large arteries and an oscillatory diastolic waveform generated principally by pulse-wave reflections from small arteries and arterioles. RESULTS: Resting heart rate was higher in smokers than nonsmokers, mean +/- SD (66 +/- 9 versus 60 +/- 10; P < 0.05). Systolic, diastolic, and mean arterial pressures were lower in smokers compared with nonsmokers (P < 0.01 for all). No differences in cardiac output, large artery compliance, or systemic vascular resistance estimates where apparent between groups. A decrease in the amplitude and duration of the diastolic wave, produced by peripheral pulse-wave reflections in the arterial system, was found in smokers compared with nonsmokers (0.04 +/- 0.02 versus 0.7 +/- 0.03; P < 0.001). CONCLUSIONS: Quantitative changes in the arterial waveform were found in long-term smokers compared with nonsmoking control subjects. The altered arterial wave shape marks the presence of abnormal structure or tone in the peripheral vasculature that affects pulsatile arterial function. This measure of vascular injury is detectable at a preclinical stage and may relate to the subsequent risk of morbid events in chronic smokers and aid in clinical risk stratification.


Assuntos
Artéria Braquial/fisiopatologia , Fumar/fisiopatologia , Adulto , Diástole , Feminino , Testes de Função Cardíaca/instrumentação , Testes de Função Cardíaca/métodos , Testes de Função Cardíaca/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Pulso Arterial , Valores de Referência , Fatores de Tempo , Resistência Vascular
7.
Am J Cardiol ; 78(6): 668-72, 1996 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-8831402

RESUMO

Endothelial injury is a central feature of vascular disease induced by cigarette smoking and may act as a precursor for future atherosclerosis. Using forearm occlusion plethysmography, we studied the vascular responses to methacholine (an endothelium-dependent vasodilator) and sodium nitroprusside (an endothelium-independent vasodilator) infused into the brachial artery of 35 long-term cigarette smokers and 16 nonsmoking subjects. NG-monomethyl-L-arginine (L-NMMA), a stereospecific inhibitor of nitric oxide production, was used to inhibit synthesis of nitric oxide in the endothelium. The reactive hyperemic response at peak and during recovery to the temporary interruption of forearm blood flow was also compared between groups. Smokers had elevated carboxyhemoglobin levels compared with nonsmokers (5.1 +/- 2.1% vs 0.8 +/- 0.4%; p < 0.001). No differences were found in the peak or late hyperemic responses between groups. In smokers, the incremental infusions of methacholine and sodium nitroprusside increased forearm blood flow from 3.6 +/- 1.2 to 12.9 +/- 9.0 ml.min-1 x 100 ml-1 and from 4.0 +/- 1.5 to 9.3 +/- 4.0 ml.min-1 x 100 ml-1, respectively, compared with 3.2 +/- 1.0 to 13.5 +/- 5.6 ml.min-1 x 100 mL-1 and from 2.9 +/- 0.7 to 8.6 +/- 4.2 ml.min-1 x 100 ml-1 in nonsmoking subjects (p = NS). L-NMMA (4 mumol/min for 5 minutes) significantly reduced forearm blood flow in both smokers and nonsmokers from 4.1 +/- 1.4 to 3.4 +/- 1.2 ml.min-1 x 100 ml-1 and 3.8 +/- 0.7 to 2.3 +/- 0.5 mL.min-1 x 100 ml-1, respectively (p < 0.01 for both); and the decrement in forearm blood flow in nonsmokers was significantly greater than that recorded in smoking subjects (p < 0.05). In this study, long-term cigarette smokers exhibited an impairment in basal, but not stimulated, nitric oxide-mediated vasodilation.


Assuntos
Endotélio Vascular/fisiopatologia , Óxido Nítrico/fisiologia , Fumar/efeitos adversos , Resistência Vascular/efeitos dos fármacos , Adulto , Artéria Braquial , Carboxihemoglobina/metabolismo , Feminino , Antebraço/irrigação sanguínea , Humanos , Infusões Intra-Arteriais , Masculino , Cloreto de Metacolina , Pessoa de Meia-Idade , Nitroprussiato , Pletismografia/métodos , Fatores de Tempo , Vasodilatadores , ômega-N-Metilarginina/sangue
8.
Hum Reprod ; 11(4): 861-7, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8671341

RESUMO

Accumulated evidence implicates immunological alterations in endometriosis. The purpose of this study was to look for variations in antibodies to distinct antigens in peritoneal fluid of women with and without endometriosis. Peritoneal fluid was aspirated from 17 women undergoing laparoscopy for tubal ligation and 37 patients complaining of symptoms of pain and/or infertility. Peritoneal fluid antibodies to a standard preparation of peritoneal fluid antigens were detected by Western blot analysis using peroxidase-labelled anti-human immunoglobulin G antibodies specific to the Fc region. Antibodies to distinct antigens were quantified by estimating the ratio of the relative optical density between samples and a standard amount of antibodies. Marked changes were found in the antibody detection to two antigens having apparent molecular weights of 22 and 18 kDa. The intensity of the antibody signal was significantly weaker in the peritoneal fluid from endometriosis patients (0.36 ± 0.06 and 0.46 ± 0.06) compared with that in women without endometriosis (0.62 ± 0.08 and 0.75 ± 0.06). It was also weaker in patients without endometriosis presenting with infertility (0.36 ± 0.07 and 0.47 ± 0.08), but only the 18 kDa antigen result was significant. After adjusting for infertility, the P values for the 18 and 22 kDa bands were 0.03 and 0.28 (not significant) respectively in the group of endometriosis patients. These changes were not related to the phase of the menstrual cycle. These data suggest an alteration in the immune response to two distinct antigens in the peritoneal fluid from women with endometriosis and infertility. Further evaluation of these two antigens and their antibodies would be of interest to help understand endometriosis and its associated infertility. Keywords: antibodies/antigens/endometriosis/peritoneal fluid/Western blot analysis

9.
Ann N Y Acad Sci ; 690: 153-66, 1993 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-8368734

RESUMO

Since 1985, we have conducted clinical trials with a therapeutic melanoma vaccine (melanoma theraccine). Mechanical lysates of two melanoma cell lines chosen for their complementary characteristics were combined with the adjuvant DETOX and injected subcutaneously on weeks 1, 2, 3, 4, and 6 for one or two courses and then monthly in patients with objective clinical responses. Of 106 patients, 20 had objective clinical regression of tumor masses, 5 with complete responses. The median duration of response was 21 months. Twelve patients lived at least 2 years, with a median survival of nearly 3 years. Two of them are free of disease for > 2 and > 6 years, respectively. However, it was not necessary to achieve complete remissions to cause an increase in survival, and most of the long-surviving patients have one or more (stable) residual nodules. The pace of the disease process was clearly slowed in those individuals. A rise in the level of cytotoxic T-lymphocyte precursors in the blood (pTC) correlated with clinical response. Only those patients who had a rise in pTC had a remission. In addition to "classical" CD8+ Tc, CD4+ Tc were cloned from the blood of immunized patients. Melanoma-specific Tc of both types that killed autologous melanoma but not matched lymphoblastoid cells were detected. Allogeneic melanoma cell lines were also killed, with mainly HLA-A2/28 and HLA-B12/44/45 degenerate restriction. CD4+ Tc were restricted by HLA Class I antigens, as judged by their killing of HLA Class II-negative melanomas and blocking by anti-class I antibodies. Other CD4+ clones were blocked by both anti-HLA Class I or anti-Class II MHC monoclonal antibodies, and only two were blocked only by anti-HLA Class II. Immunohistory revealed CD4+ and CD8+ T cells in lesions under rejection, but the predominant cells were macrophages, suggesting delayed-type hypersensitivity as a possible mechanism. Clinical responses were found most often in patients with HLA-A2/28, -B12/44/45, and -C3, particularly when two or more of those alleles were present. This may have been due either to (1) similarity of MHC antigens between one of the immunizing melanomas and the patient's melanoma or (2) the intrinsic importance of these MHC molecules in presenting melanoma-associated antigens to Tc in vivo. IFN-alpha 2 b salvaged 8 of 18 patients who failed with the theraccine, regardless of MHC phenotype, perhaps through upregulation of MHC and tumor epitopes on the autochthonous tumor.


Assuntos
Melanoma/terapia , Proteínas de Neoplasias/imunologia , Anticorpos Antineoplásicos/biossíntese , Antígenos de Neoplasias , Antígenos CD8/análise , Células Clonais , Citotoxicidade Imunológica , Rearranjo Gênico do Linfócito T , Antígenos HLA/imunologia , Humanos , Imunidade Celular , Imunoterapia Ativa , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Antígenos Específicos de Melanoma , Receptores de Antígenos de Linfócitos T/genética , Proteínas Recombinantes , Subpopulações de Linfócitos T/imunologia , Linfócitos T Citotóxicos/imunologia , Células Tumorais Cultivadas
10.
Obstet Gynecol ; 77(3): 410-5, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1825135

RESUMO

Before treatment, the trabecular bone mineral content of the lumbar spine and femoral neck was not significantly different between endometriosis patients and age-matched controls (N = 26). In 17 subjects treated with a monthly goserelin implant, serum estradiol (E2) levels were suppressed into the menopausal range. Mean decreases from pre-treatment values in the lumbar spine and femoral neck were -5.7 and -3.8% at 3 months and -8.2 and -7.7% at 6 months of treatment, respectively; lumbar spine values were significantly different (P less than .05) from those of the control group, whose values changed little during the same period. Significant increases over baseline values were also observed in urinary calcium-creatinine ratio and serum alkaline phosphatase. In nine danazol-treated subjects, serum E2 levels were generally within the early follicular-phase range. There were no significant changes in bone assessments. Normal menses returned within 2 months after cessation of either medication. Six months after goserelin treatment, the lumbar spine and femoral neck bone mineral content was still reduced but to values not significantly different from the pre-treatment and control values; urinary calcium-creatinine ratio was decreased, whereas serum alkaline phosphatase was still elevated. The rapid and deep suppression of ovarian steroidogenesis by a monthly goserelin implant induced significant bone loss compared with the control and danazol groups. This loss was not reversed completely 6 months after cessation of treatment, but bone densities at that time were not different from those of controls. Studies of larger numbers of patients followed for longer periods will be required to resolve the question of complete reversibility.


Assuntos
Densidade Óssea/efeitos dos fármacos , Busserrelina/análogos & derivados , Danazol/uso terapêutico , Endometriose/tratamento farmacológico , Neoplasias dos Genitais Femininos/tratamento farmacológico , Adulto , Fosfatase Alcalina/sangue , Busserrelina/administração & dosagem , Busserrelina/uso terapêutico , Implantes de Medicamento , Endometriose/metabolismo , Estradiol/sangue , Feminino , Colo do Fêmur , Seguimentos , Neoplasias dos Genitais Femininos/metabolismo , Gosserrelina , Humanos , Distribuição Aleatória , Coluna Vertebral
11.
Fertil Steril ; 66(1): 17-23, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8752605

RESUMO

OBJECTIVE: To estimate the concentration and the biologic activity of monocyte chemotactic protein-1 (MCP-1) in the peritoneal fluid (PF) of women with and without endometriosis. DESIGN: A case control study was conducted. SETTING: Gynecology clinic and Laboratories of endocrinology of reproduction and immunology. PATIENTS: Women presenting for infertility, pelvic pain, or tubal ligation in which endometriosis was diagnosed at laparoscopy (n = 36) and normal fertile controls presenting for tubal ligation (n = 21). INTERVENTIONS: Collection of PF via laparoscopy. MAIN OUTCOME MEASURES: Determination of PF concentrations of MCP-1 by an ELISA and evaluation of its monocyte chemotactic activity using a human hystiocytic cell line (U937). RESULTS. The concentration of MCP-1 (median, range of values) was increased in the PF of endometriosis patients (283, 0 to 1,930 pg/mL; conversion factor to SI unit, 0.155) compared with the control group (140, 0 to 435 pg/mL). The most significant elevation of MCP-1 levels was found in the stage II of the disease (371, 200 to 1,930 pg/mL). An increased chemotactic activity for monocytes (mean number of migrating cells/mm2 +/- SD) also was found in stages I (1,460 +/- 312) and II (1,541 +/- 336) of the disease when compared with fertile controls (393 +/- 56). Forty percent to 53% of this activity was inhibited in the presence of an antibody specific to MCP-1. CONCLUSIONS: These observations are consistent with previous data indicating increased leukocyte chemotaxis in the PF of patients with endometriosis and suggest that MCP-1 may play a relevant role in the peritoneal inflammatory reaction associated with the disease.


Assuntos
Líquido Ascítico/metabolismo , Quimiocina CCL2/metabolismo , Endometriose/metabolismo , Adulto , Estudos de Casos e Controles , Quimiotaxia de Leucócito , Feminino , Humanos , Monócitos/fisiologia , Concentração Osmolar
12.
Physiol Behav ; 47(5): 957-61, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2388952

RESUMO

The purpose of this study was to determine the effects of a particular psychological stress, exposure to an open-field, on plasma IL-6 activity in rats. Plasma IL-6 activity was 40.6 +/- 7.2 units/ml in control rats, 105 +/- 6.8 units/ml after 30 minutes exposure to an open-field, and 221 +/- 17 units/ml after 60 minutes of exposure (p = 0.0003). There was a positive correlation (r = .71, p = 0.043) between the change in plasma IL-6 activity and body temperature. However, we conclude, based on earlier data relating plasma IL-6 activity to body temperature changes following injection of lipopolysaccharide, that the plasma levels of IL-6 following exposure to an open-field are not high enough to account for the rise in body temperature observed in rats during this stress. In conclusion, these experiments indicate that exposure to psychological stress can elevate the plasma concentration of IL-6, a known mediator of the acute phase response.


Assuntos
Nível de Alerta/fisiologia , Regulação da Temperatura Corporal/fisiologia , Comportamento Exploratório/fisiologia , Interleucina-6/sangue , Meio Social , Animais , Masculino , Ratos , Ratos Endogâmicos
13.
Crisis ; 15(2): 65-8, 76, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7988167

RESUMO

A volunteer correspondence service was implemented in a suicide prevention center for certain frequent callers who phoned repeatedly, but whose situation did not improve. The interest in such a measure was fostered by feelings of inadequacy in a number of volunteers about handling frequent callers, which some researchers think accounts for volunteers' burnout and the high turnover. Five frequent callers with a moderate to low suicidal risk began a 6-month written correspondence with five experienced volunteers, no restrictions being made on their use of the crisisline. The frequency and length (minutes) of calls per month to the crisisline dropped for most of the callers, and the suicidal urgency of their calls remained moderate. The participants reported that rereading their correspondent's letters in times of distress had a soothing effect. In spite of having to deal with some reputedly difficult-to-manage frequent callers, all volunteers wished to renew their involvement in the correspondence service. Other suicide prevention centers are invited to experiment with this innovative type of adjunct intervention.


Assuntos
Correspondência como Assunto , Intervenção em Crise , Linhas Diretas , Prevenção do Suicídio , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Suicídio/psicologia , Voluntários/psicologia
14.
Physician Exec ; 18(2): 39-41, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-10160859

RESUMO

When I became an inspector for the New York State Health Department, I realized that I would not win any popularity contests, but I believed that I would be improving the quality of care in the 32 hospitals controlled by our area office. I decided to take the job in a desperate move to escape from primary care responsibilities that had been growing more onerous daily. This article tells of my experience as a health care regulator and why I returned to work for a health care provider.


Assuntos
Hospitais/normas , Diretores Médicos , Administração em Saúde Pública , Garantia da Qualidade dos Cuidados de Saúde/legislação & jurisprudência , Relações Interinstitucionais , Relações Interprofissionais , Satisfação no Emprego , Corpo Clínico Hospitalar/organização & administração , Corpo Clínico Hospitalar/normas , New York , Papel do Médico
17.
Am J Physiol ; 258(3 Pt 2): R798-803, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2316725

RESUMO

The purpose of these studies was to assess whether interleukin 6 (IL-6) is an endogenous pyrogen, responsible for all or part of the fever caused by lipopolysaccharide (LPS) in rats. We have found that the core temperature (as measured by biotelemetry) rose significantly after intracerebroventricular (icv) injection of recombinant human IL-6. The same doses of IL-6, when administered intravenously or intraperitoneally, had no effect on body temperature. The fever caused by icv administration of IL-6 was completely blocked by indomethacin. After injection of fever-inducing doses of LPS, the plasma and cerebrospinal fluid (CSF) IL-6 activities rose, the former much more than the latter. The correlation between fever and plasma IL-6 activity was r = 0.84 (P less than 0.0025); the correlation between fever and CSF IL-6 activity was r = 0.77 (P less than 0.015). The results of this study are consistent with the hypothesis that IL-6 is a mediator of LPS-induced fever in the rat.


Assuntos
Febre/etiologia , Interleucina-6/fisiologia , Animais , Temperatura Corporal/efeitos dos fármacos , Ventrículos Cerebrais/fisiologia , Febre/induzido quimicamente , Febre/prevenção & controle , Indometacina/farmacologia , Injeções Intraperitoneais , Injeções Intravenosas , Injeções Intraventriculares , Interleucina-6/sangue , Interleucina-6/líquido cefalorraquidiano , Lipopolissacarídeos/farmacologia , Masculino , Ratos , Ratos Endogâmicos
18.
Cytokine ; 2(4): 300-6, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2104230

RESUMO

The purpose of these studies was to test whether pentoxifylline, a drug that can inhibit the production and action of cytokines hypothesized to be endogenous pyrogens (for example, interleukin 1 and tumor necrosis factor [TNF]), is antipyretic. We also tested the effects of pentoxifylline on plasma activities of interleukin 6 (IL 6) and TNF in response to an injection of a fever-inducing dose of lipopolysaccharide (LPS). Our results showed that a high dose of pentoxifylline (200 mg/kg) caused hypothermia in control rats and blocked LPS fever, while a low dose (50 mg/kg) did not have these effects. Injection of the high dose of pentoxifylline in control rats caused a rise in plasma IL 6 but not in plasma TNF. However, the peak levels of plasma IL 6 and TNF activities following an injection of LPS were significantly reduced by pretreatment with pentoxifylline. Overall, the data are consistent with the hypothesis that pentoxifylline is an antipyretic drug, which may act at least in part by inhibiting the secretion of pyrogenic cytokines.


Assuntos
Febre/tratamento farmacológico , Interleucina-6/sangue , Lipopolissacarídeos/farmacologia , Pentoxifilina/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo , Animais , Anti-Inflamatórios não Esteroides , Temperatura Corporal/efeitos dos fármacos , Febre/induzido quimicamente , Masculino , Ratos , Ratos Endogâmicos
19.
Am J Physiol ; 259(1 Pt 2): R126-32, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2197879

RESUMO

This study was designed to test the tumor necrosis factor (TNF) WEHI 164 clone 13 bioassay and the interleukin 6 (IL-6) B9 bioassay for sensitivity to endogenously produced dog TNF and IL-6 and then to use these assays to examine the associations between these cytokines and lipopolysaccharide (LPS)-induced fever. When dogs were injected with LPS (40, 10, 1, 0.1, and 0.01 microgram/kg), the resulting fever was dose dependent. A plot of plasma cytokine changes over time following LPS injections showed that the plasma TNF-like activity appeared to increase in an all-or-none dose response, whereas the increase in plasma IL-6-like activity appeared to be log dose dependent. Plasma TNF-like and IL-6-like activity were then separately plotted against temperature change (fever). Statistical analysis supported the interpretation that both TNF-like and IL-6-like activity were related to LPS-fever in an all-or-none manner, with IL-6 having a threshold region. We conclude that if these cytokines are circulating mediators of fever, they may induce fever in an all-or-none fashion.


Assuntos
Febre/sangue , Interleucina-6/sangue , Lipopolissacarídeos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Fatores Biológicos/fisiologia , Temperatura Corporal/efeitos dos fármacos , Temperatura Corporal/fisiologia , Citocinas , Cães , Relação Dose-Resposta a Droga , Febre/induzido quimicamente , Febre/metabolismo , Interleucina-6/farmacologia , Masculino , Fator de Necrose Tumoral alfa/farmacologia
20.
Cancer Immunol Immunother ; 37(3): 187-94, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8101473

RESUMO

Twenty-five CD4+ cytotoxic T lymphocyte (CTL) clones were obtained from the peripheral blood or tumor tissues of melanoma patients undergoing active specific immunotherapy. Melanoma-reactive T cells were cloned by limiting dilution using either autologous or allogeneic melanoma cells to stimulate their proliferation. Sixteen of the clones reacted against autologous melanoma cells but not against the autologous lymphoblastoid cell line, which we defined as "melanoma-specific." Optimal demonstration of the lytic activity of CD4+ CTL required a 16-h incubation period and an effector:target cell ratio of 40:1. In addition, a 24-h pre-incubation of the target melanoma cells with 100 U interferon (IFN) gamma consistently augmented lysis by these CD4+ CTL, increasing it from a mean level of 20% to one of 52%. Lysis by 8 of the 11 melanoma-reactive CD4+ T cell clones was exclusively HLA-class-I-restricted, as judged by blocking with monoclonal antibodies (mAb). Five of these HLA class-I-restricted clones were reactive only with the autologous melanoma cells, while the other 3 clones were also reactive with allogeneic melanoma cells. In all cases, the T cells and melanoma targets shared at least one HLA class I allele, usually HLA-A2, HLA-C3 or HLA-B62. Interestingly, lysis by 2 of the 11 clones was inhibited by both anti-HLA-class-I or -HLA-class-II mAb, while lysis by 1 other clone was inhibited by neither. HLA class I molecules and several accessory molecules were maximally expressed by the melanoma target cells, both in terms of distribution and copy number before IFN gamma treatment. Thus, IFN gamma may have acted by increasing the expression of melanoma-associated epitopes as presented by HLA class I (or HLA class II) molecules. A proportion of human CD4+ CTL appeared to recognize melanoma-associated epitopes presented by the HLA class I molecule, although their lytic potency may be less than that of their CD8+ counterparts.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Interferon gama/imunologia , Melanoma/terapia , Linfócitos T Citotóxicos/imunologia , Células Clonais , Citotoxicidade Imunológica/efeitos dos fármacos , Citometria de Fluxo , Antígenos HLA/análise , Humanos , Imunofenotipagem , Imunoterapia , Interferon gama/uso terapêutico , Melanoma/imunologia , Células Tumorais Cultivadas
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