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1.
Digestion ; 86(3): 218-27, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22964578

RESUMO

BACKGROUND: Chronic hepatitis C virus genotype 1 (HCV-G1) infection is treated with pegylated interferon-α and ribavirin. Predictive factors for treatment success are even more important now as direct-acting antiviral agents are available. METHODS: Clinical and laboratory parameters were analyzed by uni- and multivariate statistical means in 264 patients with HCV-G1 infections with regard to treatment outcome. RESULTS: The overall sustained virological response (SVR) rate was 44%. Univariate analyses revealed SVRs to be associated with age, high alanine aminotransferase (ALT) and low γ-glutamyltransferase (γ-GT) serum activities, a low pretreatment γ-GT/ALT ratio, rapid virological response (RVR), and absence of steatosis. Multivariate analyses unveiled IL28B rs12979860 genotype (CC vs. CT: OR = 2.8, CI: 1.5-4.9, p = 0.001; CC vs. TT: OR = 7.1, CI: 3.1-16.7, p < 0.001), low pretreatment γ-GT/ALT ratio (OR = 2.5, CI: 1.7-3.3, p < 0.001), age (OR = 0.96, CI: 0.94-0.98, p = 0.001) and RVR (OR = 4.18, CI: 2.85-8.65, p < 0.001) to be significantly related to treatment outcome. Patients with the IL28B rs12979860 CC genotype and a low pretreatment γ-GT/ALT ratio achieved the highest rate of a SVR with the highest predictive values (OR = 26.7, 95% CI: 10-71.1, p < 0.0001). CONCLUSION: The pretreatment γ-GT/ALT ratio significantly enhances the predictability of the IL28B genotype. Employing this combination will help to identify patients who will most likely benefit from an interferon-α-based combination therapy in a nontriaged ordinary setting.


Assuntos
Alanina Transaminase/sangue , Hepacivirus/genética , Hepatite C Crônica/virologia , Interleucinas/genética , Polimorfismo Genético , RNA Viral/análise , gama-Glutamiltransferase/sangue , Adulto , Idoso , Antivirais/uso terapêutico , DNA/genética , Feminino , Genótipo , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/metabolismo , Humanos , Interferons , Interleucinas/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
2.
Dig Dis Sci ; 57(1): 215-20, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22160636

RESUMO

BACKGROUND: Hepatitis B virus (HBV) vaccination is essential in chronic liver disease (CLD), because it can help prevent acute-on-chronic disease, which has potentially fatal complications. Unfortunately, this group has a significant proportion of HBV vaccination non-responders. A variety of intra-muscular (IM) vaccination methods have been used in an attempt to remedy this poor-response, but with limited success. AIMS: Herein is reported the safety and efficacy of high-dose intra-dermal (ID) HBV vaccination in CLD individuals who had failed previous IM standard and boost-dosing regimens. METHODS: Forty-eight CLD individuals, known HBcAb negative, who had failed both a three-dose schedule of 40 µg IM vaccination, and boost dosing of either 40 or 80 µg IM, were identified, of which 42 completed the vaccination course. Each received a 40 µg ID total dose (20 µg per arm) during their clinic visits until a response was documented or a maximum of three doses had been administered. HBsAb titer ≥ 10 mIU/ml was regarded as an immunologic response; the intention was to achieve an optimum response of ≥ 100 mIU/ml. RESULTS: Twenty-nine of forty-two (69%) individuals had an immunologic response, with 15 (51%) of the responders having the optimum response. No changes in serologic data occurred. No serious dermatologic reactions were observed. No differences between those who responded and those who did not were observed with regard to the presence of cirrhosis, diabetes mellitus, or chronic kidney disease. CONCLUSIONS: High-dose ID HBV vaccination of previous CLD non-responders to the standard IM regimen with boost dosing is both safe and efficacious, and should be considered for all such groups.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Vacinas contra Hepatite B/uso terapêutico , Vírus da Hepatite B/imunologia , Hepatite B/prevenção & controle , Hepatopatias/imunologia , Adulto , Idoso , Doença Crônica , Relação Dose-Resposta a Droga , Feminino , Vacinas contra Hepatite B/efeitos adversos , Humanos , Injeções Intradérmicas , Hepatopatias/sangue , Masculino , Pessoa de Meia-Idade , Padrões de Prática Médica , Estudos Retrospectivos , Resultado do Tratamento
3.
Science ; 218(4571): 493-4, 1982 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-7123252

RESUMO

Exposure of rats to cimetidine during intrauterine life and the immediate neonatal period results in hypoandrogenization in adult life with decreased weights of androgen-dependent tissues and decreased concentrations of testosterone. Moreover, sexual behavior patterns in adult life are disturbed as shown by a lack of sexual motivation and decreased performance.


Assuntos
Anormalidades Induzidas por Medicamentos/etiologia , Cimetidina/toxicidade , Guanidinas/toxicidade , Diferenciação Sexual/efeitos dos fármacos , Animais , Animais Lactentes , Cimetidina/metabolismo , Feminino , Masculino , Gravidez , Prenhez/efeitos dos fármacos , Ratos , Comportamento Sexual Animal/efeitos dos fármacos
4.
Science ; 186(4167): 941-2, 1974 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-4469692

RESUMO

Vitanin A (retinol) is essential for spermatogenesis. Alcohol dehydrogenase, the enzyme responsible for ethanol metabolism, is also required for the conversion of retinol to bioactive retinal at the end organ site. Ethanol inhibits the oxidation of retinol by testicular homogenates containing alcohol dehydrogenase. Thus, a possible biochemnical mechanism for the sterility of chronic alcoholics is identified.


Assuntos
Oxirredutases do Álcool/metabolismo , Etanol/farmacologia , Vitamina A/metabolismo , Oxirredutases do Álcool/antagonistas & inibidores , Animais , Anuros/crescimento & desenvolvimento , Técnicas In Vitro , Infertilidade Masculina/induzido quimicamente , Masculino , Ratos , Retinaldeído/metabolismo , Testículo/enzimologia , Testículo/metabolismo
5.
Science ; 169(3952): 1326-7, 1970 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-4318262

RESUMO

We have analyzed 88 pregnancies in 50 women who had previously been treated for gestational trophoblastic neoplasms with chemotherapeutic agents. No increase in fetal wastage, congenital abnormalities or complicated pregnancies was noted, suggesting that these drugs do not damage human oocytes in the doses and time periods used. The possibility that recessive mutations have been induced but were undetected cannot be evaluated definitively at present.


Assuntos
Antineoplásicos/uso terapêutico , Complicações na Gravidez/tratamento farmacológico , Gravidez , Neoplasias Trofoblásticas/tratamento farmacológico , Aborto Espontâneo , Descolamento Prematuro da Placenta , Compostos Azo/uso terapêutico , DNA/biossíntese , Dactinomicina/uso terapêutico , Surdez/genética , Eczema/congênito , Edema , Feminino , Morte Fetal , Seguimentos , Bócio/genética , Hemangioma/congênito , Humanos , Hiperêmese Gravídica , Iodo/metabolismo , Mecloretamina/uso terapêutico , Metotrexato/uso terapêutico , Mutação , Placenta Acreta , Hemorragia Pós-Parto , Estrabismo/congênito , Tetralogia de Fallot , Vimblastina/uso terapêutico
6.
J Clin Invest ; 61(3): 624-32, 1978 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-641143

RESUMO

The effect of ethanol feeding on ovarian function and structure in female rats was studied in alcohol-fed animals, isocalorically fed controls, and two ad libitum-fed control groups. Ovarian weight was reduced by 60% in alcohol-fed animals compared with the control groups. Gross disruption of ovarian architecture was noted, characterized by the absence of any corpus hemorrhagicum and corpus albicans. Moreover, plasma levels of estradiol were significantly reduced in the alcohol-fed animals (P < 0.01) compared with the levels found in isocaloric controls. Plasma levels of estrone and corticosterone were increased in alcoholfed and isocaloric control animals relative to those of ad libitum-fed animals suggesting a primarily adrenal, rather than ovarian, origin for these two steroids. Despite the increase in estrone, the secondary sex organs (uterus and fallopian tubes) reflected marked estrogen deprivation presumably as a result of estradiol insufficiency. Progesterone levels in the alcohol-fed animals were significantly less than levels in the isocaloric and intact ad libitum-fed controls but were not significantly different compared to oophorectomized animals. Plasma follicle-stimulating hormone levels were similar in alcohol-fed, isocaloric controls, and ad libitum-intact controls. They were, however, one-third the level of oophorectomized controls. Both alcohol-fed and isocaloric controls had increased levels of plasma luteinizing hormone, although levels were below those seen in oophorectomized controls (P < 0.01). The results establish that ingestion of a diet containing 5% ethanol for periods as short as 6 wk produces functional and histologic ovarian failure in the female rat.


Assuntos
Etanol/efeitos adversos , Ovário/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Corticosterona/sangue , Etanol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Hormônios Esteroides Gonadais/sangue , Fígado/anatomia & histologia , Fígado/efeitos dos fármacos , Fígado/fisiologia , Hormônio Luteinizante/sangue , Tamanho do Órgão/efeitos dos fármacos , Ovário/anatomia & histologia , Ovário/fisiologia , Ratos
7.
J Clin Invest ; 63(5): 1042-9, 1979 May.
Artigo em Inglês | MEDLINE | ID: mdl-447826

RESUMO

Taurocholate concentrations in fetal and neonatal rats were determined by radioimmunoassay. Total body taurocholate pool size varied from 0.0049 +/- 0.0008 to 203 +/- 8 nmol/g body weight from day 5 of gestation to 5 d after birth. A 50-fold increase in taurocholate pool size was observed between days 15 and 19 of gestation. The distribution of taurocholate between liver, intestine, and the remainder of the carcass was determined for rats of gestational age 19 d to 5 d after birth. The major fraction of total body taurocholate was in the liver and intestine, with less than 15% in the remainder of the carcass. The ratio of taurocholate in intestine to taurocholate in liver, which was 1:17 at 19 d of gestation, had altered substantially to a ratio of 6:1 by 5 d after birth. Treatment of pregnant rats with 60 microgram/d of dexamethasone from gestational day 9 until sacrifice increased fetal taurocholate pool size by 80% at 15 d, 40% at 19 d, and 16% at 1 d after birth. Administration of dexamethasone to the mother also changed the ratio of taurocholate in intestine to taurocholate in liver. At 19 d of gestation, dexamethasone-treated mothers had fetuses with approximately equal amounts of taurocholate in intestine and liver. This suggested that adrenocorticosteroids stimulate the early maturation of factors controlling taurocholate pool size and tissue distribution in the rat fetus.


Assuntos
Feto/metabolismo , Ácido Taurocólico/metabolismo , Animais , Animais Recém-Nascidos/metabolismo , Ácidos Cólicos/metabolismo , Dexametasona/farmacologia , Feto/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Fenobarbital/farmacologia , Radioimunoensaio , Ratos
8.
J Clin Invest ; 51(4): 1009-19, 1972 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-4552337

RESUMO

The interaction of the testis and gonadotropin secretion was studied in 15 men surviving chemotherapy for lymphoma. Azoospermia and complete destruction of all testicular germinal elements were present in 10 of the 15 men; however, Sertoli cells and Leydig cells were present. In these 10 men plasma follicle-stimulating hormone (FSH) levels were fourfold higher than in normal men of similar age whereas luteinizing hormone (LH) levels were normal. In contrast, both FSH and LH were normal in the remaining five men. Three had a full complement of spermatogenic tissue on biopsy and normal sperm concentrations. The other two men were azoospermic; one demonstrated full spermatogenesis in 30% of his tubules; the other had only a few spermatogonia in all tubules. In those patients with lower levels of gonadotropins pituitary insufficiency was excluded by the demonstration of appropriate responsiveness of FSH and LH to clomiphene administration. Similarly, Leydig cell function was normal since plasma testosterone was within the normal range in 13 of the 15 men and only slightly decreased in two. Thus, following chemotherapy, testicular damage was restricted to the germinal tissue, and this in turn was associated with a selective increase in FSH. The source of the FSH inhibitor is either the Sertoli cell or early germinal elements. However, since FSH levels are only half as high as those reported for castrate men, other testicular factors may modify FSH secretion.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Testículo/fisiologia , Adulto , Biópsia , Contagem de Células , Clomifeno , Ciclofosfamida/uso terapêutico , Hormônio Foliculoestimulante/sangue , Doença de Hodgkin/tratamento farmacológico , Humanos , Hidrazinas/uso terapêutico , Infertilidade Masculina/fisiopatologia , Hormônio Luteinizante/sangue , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Masculino , Mecloretamina/uso terapêutico , Pessoa de Meia-Idade , Prednisona/uso terapêutico , Radioimunoensaio , Sêmen/citologia , Espermatogênese , Espermatozoides , Testículo/patologia , Testosterona/sangue , Vincristina/uso terapêutico
9.
J Clin Invest ; 80(4): 1200-4, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3654978

RESUMO

Deficiency of serum ceruloplasmin is a characteristic biochemical abnormality of Wilson's disease, although the mechanism of this finding is unknown. Ceruloplasmin messenger RNA (mRNA) levels were therefore examined in five patients with Wilson's disease and five controls with other types of hepatic disease. Northern and dot blot hybridizations showed that detectable ceruloplasmin mRNA was present in all of the patients with Wilson's disease, including one patient with no detectable serum ceruloplasmin. However, the ceruloplasmin mRNA levels in the Wilson's disease patients were only 33% that of controls (P less than 0.001). In contrast, albumin mRNA levels in the Wilson's disease patients averaged 161% that of controls. In an attempt to better delineate the level of gene expression responsible for this decrease in ceruloplasmin mRNA, the nuclear run-on assay was used to analyze transcriptional rates. The amount of ceruloplasmin gene transcription in four Wilson's patients was decreased to 44% that of three controls. These results indicate that the diminished serum ceruloplasmin levels in patients with Wilson's disease are due at least in part to a decrease in ceruloplasmin gene transcription.


Assuntos
Ceruloplasmina/deficiência , Degeneração Hepatolenticular/genética , Ceruloplasmina/genética , Degeneração Hepatolenticular/sangue , Humanos , Hibridização de Ácido Nucleico , RNA Mensageiro/análise , Albumina Sérica/genética , Transcrição Gênica
10.
Cancer Res ; 47(21): 5600-5, 1987 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-3664466

RESUMO

A factor has been isolated from weanling rat liver which stimulates in vivo hepatic DNA synthesis in a dose dependent manner when injected into 40% hepatectomized rats. The factor has been partially purified by successive steps, involving ethanol precipitation, ultrafiltration through an Amicon PM 30 membrane, and finally fast protein liquid chromatography, resulting in a 38,000-fold increase in specific activity over that in the original cytosol. The factor contains a few bands in the molecular weight range of 14,000-50,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Active fractions from fast protein liquid chromatography (F150), when injected into 40% hepatectomized rats, increased hepatic DNA synthesis 3-fold over the background stimulation due to the hepatectomy. The response was dose dependent over a range from 1.76 micrograms to 6.8 micrograms per 200-g (body weight) rat. Mitotic and labeling indexes confirmed that F150 stimulates both replicative DNA synthesis and cell proliferation. The factor is heat and neuraminidase resistant, trypsin sensitive, organ specific, but not species specific.


Assuntos
DNA/biossíntese , Substâncias de Crescimento/isolamento & purificação , Fígado/efeitos dos fármacos , Animais , Citosol/análise , Cães , Substâncias de Crescimento/análise , Substâncias de Crescimento/farmacologia , Fígado/metabolismo , Regeneração Hepática/efeitos dos fármacos , Masculino , Camundongos , Peso Molecular , Especificidade de Órgãos , Ratos , Ratos Endogâmicos F344 , Especificidade da Espécie
11.
Biochim Biophys Acta ; 1177(1): 1-7, 1993 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-8485164

RESUMO

Ca2+ antagonists were studied during anoxia in perfused isolated rat hepatocytes. Cytosolic free calcium (Ca2+i) was measured with aequorin. Anoxia was induced for 2 h by saturating the perfusate with 95% N2/5+ CO2. Anoxia increased Ca2+i in two distinct phases reaching a maximum of 1.5 microM. The increase in Ca2+i was caused by Ca2+ influx from the extracellular fluids because the main Ca2+i surge was totally abolished in Ca(2+)-free media. LDH release increased 6-fold during the second hour of anoxia, but when Ca2+ was removed from the perfusate during the anoxic period, LDH rose only 2.7-fold. Ca2+ antagonists (10(-7) to 10(-5) M) did not prevent the increase in Ca2+i and the rise in LDH release. On the contrary, high concentrations (10(-6) and 10(-5) M) of the blockers nifedipine and diltiazem significantly increased anoxic cell injury. The observation that the increase in LDH and the rise in Ca2+i were not suppressed by Ca2+ antagonists suggests that (i) Ca2+ antagonists protect the whole liver from anoxic injury by acting on cells other than parenchymal cells; (ii) the influx of Ca2+ responsible for the massive increase in hepatocyte Ca2+i evoked by anoxia did not take place through voltage-sensitive Ca2+ channels but must have occurred via the Na(+)-Ca2+ antiporter operating in the reverse mode (Ca2+ influx vs. Na+ efflux), and (iii) high concentrations of Ca2+ antagonists may be deleterious to the parenchymal cells of the liver.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Hipóxia Celular/efeitos dos fármacos , Fígado/efeitos dos fármacos , Animais , Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Fígado/citologia , Masculino , Ratos , Ratos Sprague-Dawley , Azul Tripano/metabolismo
12.
Biochim Biophys Acta ; 1178(1): 9-19, 1993 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-8329459

RESUMO

The effect of fasting and anoxia on the intracellular concentration of ATP, Na+, Ca2+, Mg2+, and H+ was studied in isolated perfused rat hepatocytes. ATP and intracellular Mg2+ were measured by 31P-NMR spectroscopy, cytosolic free calcium was measured with aequorin, intracellular Na+ with SBFI, intracellular pH with BCECF, lactic dehydrogenase by NADH absorbance. In hepatocytes from fasted rats, intracellular ATP was depressed 52% (P < 0.001), Nai+ was increased 70% from 16.9 to 27.7 mM (P < 0.02), and Cai2+ was increased 79% from 137 to 245 nM (P < 0.05) when compared to fed rats. Mgi2+ and pHi were unchanged. During anoxia, ATP and the cell phosphorylation potential decreased 90% to practically the same low levels in both fed and fasted groups. On the other hand, in hepatocytes from fasted animals, Cai2+ increased faster and to significantly higher levels than in hepatocytes from fed rats: Cai2+ reached 2.19 microM in 10 min compared to 1.45 microM in 1 h, respectively (P < 0.05). Cell injury assessed by LDH release and trypan blue exclusion also occurred earlier and was more severe in hepatocytes from fasted rats. Fructose and Ca(2+)-free perfusion reduced the rise in Cai2+, abolished LDH release and significantly improved the cell viability measured by Trypan blue exclusion. The data demonstrate that fasting decreases the hepatocytes energy potential and increases Nai+ and Cai2+ which are inversely related to the cell energy potential. Consequently, in hepatocytes isolated from fasted rats, the increase in Cai2+ and the resulting cell injury evoked by anoxia occur earlier and are more severe than in fed rats. These results suggest that Ca2+ plays a crucial role in the development of anoxic cell injury.


Assuntos
Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , Hipóxia Celular , Jejum , Trifosfato de Adenosina/análise , Animais , Células Cultivadas , Concentração de Íons de Hidrogênio , L-Lactato Desidrogenase/análise , Magnésio/análise , Masculino , Ratos , Ratos Sprague-Dawley , Sódio/análise , Azul Tripano
13.
Biochim Biophys Acta ; 1268(3): 249-54, 1995 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-7548222

RESUMO

The aim of this study was to determine the cellular source of oxygen free radicals generated by isolated hepatocytes during post-anoxic reoxygenation. Superoxide anions (O2.-) were detected by lucigenin chemiluminescence. Cell damage was assessed by LDH release. During anoxia, the chemiluminescence decreased to background levels while LDH release increased 8-fold. During reoxygenation, O2.- formation increased 15-fold within 15 min then declined towards control levels. LDH release increased from 161 to 285 mU/min in the first 30 min of reoxygenation, then declined toward the control rate. Allopurinol, an inhibitor of the xanthine-xanthine oxidase system, did not inhibit O2.- formation nor LDH release. Antimycin, a mitochondrial complex III inhibitor that does not block O2.- formation, increased both O2.- generation and LDH release 82 and 133% respectively. Diphenyleneiodonium (DPI), a mitochondrial and microsomal NADPH oxidase inhibitor, reduced O2.- and LDH release 60-70%. SOD, which catalyzes the dismutation of O2.- to H2O2, was without effect on O2.- and LDH release, but TEMPO, a stable nitroxide which mimics SOD and easily penetrates the cell membrane, decreased O2.-86% without affecting LDH. These results suggest that mitochondria or microsomes are the principal sites of O2.- production during reoxygenation of isolated hepatocytes, whereas the cytosolic xanthine/xanthine oxidase system is apparently not involved.


Assuntos
Antimicina A/farmacologia , Fígado/metabolismo , Oxigênio/metabolismo , Superóxidos/metabolismo , Alopurinol/farmacologia , Animais , Células Cultivadas , Óxidos N-Cíclicos/farmacologia , Hipóxia/metabolismo , L-Lactato Desidrogenase/análise , Masculino , Microssomos Hepáticos/metabolismo , Mitocôndrias Hepáticas/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/farmacologia , Xantina Oxidase/antagonistas & inibidores
14.
Biochim Biophys Acta ; 1220(3): 277-85, 1994 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-8305500

RESUMO

The effect of high and low pH on anoxic cell injury was studied in freshly isolated rat hepatocytes cast in agarose gel threads and perfused with Krebs-Henseleit bicarbonate buffer (KHB) saturated with 95% O2 and 5% CO2. Cytosolic free calcium (Ca2+i) was measured with aequorin, intracellular pH (pHi) with BCECF, and lactic dehydrogenase (LDH) by the increase in NADH absorbance during lactate oxidation to pyruvate. A 2 h period of anoxia was induced by perfusing the cells with KHB saturated with 95% N2 and 5% CO2. The extracellular pH (pHo) was maintained at 7.4, 6.8 or 8.0 by varying the bicarbonate concentration. The substrate was either 5 mM glucose, 15 mM glucose or 15 mM fructose. In some experiments, anoxia was performed in Ca(2+)-free media by perfusing the cells with KHB without Ca2+ but with 0.1 mM EGTA. Reducing pHo to 6.8 during anoxia did not reduce the increase in Ca2+i, but but completely abolished LDH release. Under these conditions, pHi decreased to 6.56 +/- 0.3 when glucose was the substrate and to 6.18 +/- 0.25 with 15 mM fructose. Apparently, protection against anoxic injury caused by a low pHo is associated with a low pHi but not with a reduced elevation in Ca2+i. Increasing pHo to 8.0 during anoxia increased pHi above 8.0 +/- 0.01 and doubled LDH release without significantly altering the rise in Ca2+i. When 15 mM fructose was present with a pHo of 8.0, pHi was still 8.0, but there was practically no rise in Ca2+i, and LDH release was again completely abolished. On the other hand, a Ca(2+)-free perfusate with a pHo of 8.0 kept the rise in Ca2+i below 400 nM but did not abolish the massive release of LDH caused by high pH. Since cell injury is caused by the activation of Ca(2+)-sensitive hydrolytic enzymes such as phospholipase A2, these experiments suggest that a low pH (< 6.5) prevents their activation even in the presence of a high Ca2+i. Conversely, a high pH (> 8.0) can activate hydrolytic enzymes and cause injury even in the absence of an elevated Ca2+i. The precise mechanism by which fructose protects hepatocytes against cell injury at pHi 8.0 is unclear.


Assuntos
Cálcio/metabolismo , Hipóxia Celular , Concentração de Íons de Hidrogênio , Fígado/metabolismo , Fígado/patologia , Animais , Células Cultivadas , Ácido Egtázico/farmacologia , Frutose/farmacologia , Glucose/farmacologia , Cinética , L-Lactato Desidrogenase/análise , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
15.
Biochim Biophys Acta ; 1139(1-2): 105-14, 1992 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-1610910

RESUMO

A system consisting of isolated rat hepatocytes immobilized in agarose threads continuously perifused with oxygenated Krebs-Henseleit (KH) solution has been found to maintain cell viability with excellent metabolic activity for more than 6 h. The hepatocytes were monitored by phosphorus-31 nuclear magnetic resonance (31P-NMR) spectroscopy at 4.7 Tesla, by measurement of oxygen consumption and by the leakage of lactate dehydrogenase (LD) and alanine aminotransferase (ALT). The data obtained were comparable to those found for an isolated perfused whole liver in vitro. The effects of allyl alcohol (AA), ethanol, and 4-acetaminophenol (AP) were examined. A solution of 225 microM AA perifused for 90 min caused the disappearance of the beta-phosphate resonance of adenosine triphosphate (ATP) in the 31P-NMR spectra, a 7-fold increase in LD leakage and a 70% reduction in oxygen consumption. Ethanol (1.0 M) perifused for 90 min reduced the beta-ATP signal intensity ratio by 20%, the phosphomonoester (PME) signal by 50% and inorganic phosphate (Pi) by 33% (P less than 0.05). AP (10 mM) caused only mild liver-cell damage. The results demonstrate that perifused immobilized hepatocytes can be used as a liver model to assess the effects of a wide range of chemicals and other xenobiotics by NMR spectroscopy.


Assuntos
Fígado/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Citosol/enzimologia , Metabolismo Energético/efeitos dos fármacos , Etanol/farmacologia , Técnicas In Vitro , L-Lactato Desidrogenase/análise , Fígado/enzimologia , Fígado/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Perfusão , Ratos , Ratos Endogâmicos , Sefarose
16.
J Clin Oncol ; 2(6): 637-42, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6327930

RESUMO

Computerized tomography (CT) of liver is used in oncologic practice for staging tumors, evaluating response to treatment, and screening patients for hepatic resection. Because of the impact of CT liver scan on major treatment decisions, it is important to assess its accuracy. Patients undergoing liver transplantation or resection provide a unique opportunity to test the accuracy of hepatic-imaging techniques by comparison of findings of preoperative CT scan with those at gross pathologic examination of resected specimens. Forty-one patients who had partial hepatic resection (34 patients) or liver transplantation (eight patients) for malignant (30 patients) or benign (11 patients) tumors were evaluable. Eight (47%) of 17 patients with primary malignant liver tumors, four (31%) of 13 patients with metastatic liver tumors, and two (20%) of 10 patients with benign liver tumors had tumor nodules in resected specimens that were not apparent on preoperative CT studies. These nodules varied in size from 0.1 to 1.6 cm. While 11 of 14 of these nodules were less than 1.0 cm, three of 14 were greater than 1.0 cm. These results suggest that conventional CT alone may be insufficient to accurately determine the presence or absence of liver metastases, extent of liver involvement, or response of hepatic metastases to treatment.


Assuntos
Adenoma de Ducto Biliar/diagnóstico por imagem , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Transplante de Fígado , Tomografia Computadorizada por Raios X , Adenoma de Ducto Biliar/cirurgia , Carcinoma Hepatocelular/cirurgia , Neoplasias do Colo , Humanos , Fígado/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Neoplasias Retais
17.
Diabetes ; 27(11): 1092-7, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-720769

RESUMO

There is an increased prevalence (P less than 0.001) of IgA deficiency in children with juvenile-onset insulin-dependent diabetes mellitus (9/366) but not in adults with insulin-dependent diabetes (0/421). The juvenile diabetics with IgA deficiency have other immune-associated diseases, such as thyroiditis and chronic active hepatitis, and have a history of infections. Four of the nine IgA-deficient diabetics we studied have autoantibodies to endocrine organs. Seven of eight have the HLA-B8, a proportion significantly (P less than 0.05) greater than control populations. Based on the clinical findings of IgA deficiency and multiple autoantibodies in patients with ataxia-telangiectasia and chronic mucocutaneous candidiasis, diseases associated with thymus deficiency, we suspect that thymus deficiency and autoimmunity may play a role in the pathogenesis of some types of juvenile-onset diabetes mellitus. In addition, an excess morbidity of the IgA-deficient juvenile diabetic population may explain the lack of IgA deficiency in older insulin-dependent diabetic individuals.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Disgamaglobulinemia/imunologia , Imunoglobulina A , Adolescente , Adulto , Criança , Diabetes Mellitus/imunologia , Diabetes Mellitus Tipo 1/complicações , Disgamaglobulinemia/complicações , Feminino , Humanos , Masculino
18.
Free Radic Biol Med ; 38(6): 698-710, 2005 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15721980

RESUMO

Oxidation products of lipids, proteins, and DNA in the blood, plasma, and urine of rats were measured as part of a comprehensive, multilaboratory validation study searching for noninvasive biomarkers of oxidative stress. This article is the second report of the nationwide Biomarkers of Oxidative Stress Study using acute CCl4 poisoning as a rodent model for oxidative stress. The time-dependent (2, 7, and 16 h) and dose-dependent (120 and 1200 mg/kg i.p.) effects of CCl4 on concentrations of lipid hydroperoxides, TBARS, malondialdehyde (MDA), isoprostanes, protein carbonyls, methionine sulfoxidation, tyrosine products, 8-hydroxy-2'-deoxyguanosine (8-OHdG), leukocyte DNA-MDA adducts, and DNA-strand breaks were investigated to determine whether the oxidative effects of CCl4 would result in increased generation of these oxidation products. Plasma concentrations of MDA and isoprostanes (both measured by GC-MS) and urinary concentrations of isoprostanes (measured with an immunoassay or LC/MS/MS) were increased in both low-dose and high-dose CCl4-treated rats at more than one time point. The other urinary markers (MDA and 8-OHdG) showed significant elevations with treatment under three of the four conditions tested. It is concluded that measurements of MDA and isoprostanes in plasma and urine as well as 8-OHdG in urine are potential candidates for general biomarkers of oxidative stress. All other products were not changed by CCl4 or showed fewer significant effects.


Assuntos
Intoxicação por Tetracloreto de Carbono/metabolismo , Tetracloreto de Carbono/toxicidade , DNA/metabolismo , Desoxiguanosina/análogos & derivados , Metabolismo dos Lipídeos , Estresse Oxidativo , 8-Hidroxi-2'-Desoxiguanosina , Animais , Ensaio Cometa , Dano ao DNA , Desoxiguanosina/farmacologia , Radicais Livres , Cromatografia Gasosa-Espectrometria de Massas , Peróxido de Hidrogênio/metabolismo , Imunoensaio , Immunoblotting , Fígado/metabolismo , Masculino , Malondialdeído/farmacologia , Metionina/metabolismo , Oxigênio/metabolismo , Ratos , Ratos Endogâmicos F344 , Espectrofotometria , Substâncias Reativas com Ácido Tiobarbitúrico , Fatores de Tempo , Tirosina/química , Tirosina/metabolismo
19.
Arch Intern Med ; 147(2): 274-7, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3813745

RESUMO

Hypercalcemia has not previously been recognized as a complication of advanced chronic liver disease without hepatoma. During a five-year period, 16 patients evaluated in the liver transplantation program at the University of Pittsburgh developed hypercalcemia. All had advanced chronic liver disease with mean total bilirubin concentration of 29.5 +/- 4.6 mg/dL (50.1 +/- 78.2 mumol/L) (mean +/- SEM) and prothrombin time 16.8 +/- 0.8s. The highest serum calcium level was 17.2 mg/dL (4.3 mmol/L). The mean serum calcium level was 11.7 +/- 0.3 mg/dL (2.93 +/- 0.075 mmol/L) with an ionized calcium level of 5.41 +/- 0.35 mg/dL (1.35 +/- 0.088 mmol/L) and a phosphorus level of 4.2 +/- 0.4 mg/dL (1.4 +/- 0.1 nmol/L). Mild to moderate renal insufficiency was present in 14 (87%) patients; the mean serum creatinine level was 2.8 +/- 0.4 mg/dL (247 +/- 35 mumol/L). In five (38%) patients parathyroid hormone was completely suppressed and in an additional five (38%) patients, it was in a range most compatible with nonhyperparathyroid hypercalcemia. The 25-hydroxyvitamin D or 1,25-dihydroxyvitamin D levels were normal or low in the 11 patients in whom determinations were made. Hypercalcemia that is not due to hyperparathyroidism or hypervitaminosis D is a potential complication of advanced chronic liver disease.


Assuntos
Hipercalcemia/etiologia , Hepatopatias/complicações , Adulto , Bilirrubina/sangue , Cálcio/sangue , Doença Crônica , Creatinina/sangue , Di-Hidroxicolecalciferóis/sangue , Feminino , Humanos , Hidroxicolecalciferóis/sangue , Falência Renal Crônica/complicações , Hepatopatias/sangue , Masculino , Pessoa de Meia-Idade , Tempo de Protrombina
20.
Arch Intern Med ; 149(8): 1793-8, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2669664

RESUMO

1,1,1-trichloroethane is a halogenated hydrocarbon solvent commonly used in industry because of its supposed lack of hepatotoxicity. Nonetheless, animal studies performed by several independent groups have shown the solvent to induce fat deposition, vacuolar degeneration, and centrilobular necrosis, changes similar to those seen after exposure to carbon tetrachloride, albeit of a much reduced magnitude, in animals exposed to the agent. Four patients with fatty liver disease whose work entailed substantial exposure to this agent were seen at the University of Pittsburgh (Pa). Based on this clinical experience, we believe that 1,1,1-trichloroethane should be reconsidered as an agent with potential hepatotoxicity in man.


Assuntos
Fígado Gorduroso/induzido quimicamente , Hidrocarbonetos Clorados/efeitos adversos , Doenças Profissionais/induzido quimicamente , Solventes/efeitos adversos , Tricloroetanos/efeitos adversos , Adulto , Exposição Ambiental , Humanos , Cirrose Hepática/induzido quimicamente , Masculino , Pessoa de Meia-Idade
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