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1.
Natl Med J India ; 25(4): 207-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23278777

RESUMO

BACKGROUND: In July 2010, we started universal individual donor nucleic acid testing (ID-NAT) at our blood bank. This test simultaneously detects human immunodeficiency virus-1 (HIV-1), hepatitis B virus (HBV) and hepatitis C virus (HCV) in samples of donor blood. We continued to do the enzymelinked immunosorbent assay (ELISA) test for these agents, as per the guidelines of the Drug Controller General of India. We assessed the impact of ID-NAT in preventing transfusionassociated transmission of viruses. METHODS: We used fourth generation ELISA to screen blood samples of all voluntary and replacement blood donors. ID-NAT was done by transcription-mediated amplification (TMA). RESULTS: Of the 18 356 donors, ID-NAT could not be performed on 2 samples which were inadequate. Of the 18 354 donors tested by both ID-NAT and fourth generation ELISA, 7 were found to be NAT-positive but ELISA-negative (NAT yield) for HBV and HCV. The prevalence of NAT yield cases among routine donors was 1 in 2622 donations tested (0.038%). Since we supply blood as components (packed red cells, fresh frozen plasma and platelet concentrate), these 7 units of blood would have yielded 21 components and hence 21 patients could have been infected with HBV and HCV viruses. CONCLUSION: In the vast majority of blood units tested, the results of ELISA and ID-NAT for HIV-1, HBV and HCV were concordant. ID-NAT did detect the presence of viruses missed by ELISA in some blood units. It widespread use in blood banks would ensure safer blood transfusion.


Assuntos
Bancos de Sangue/normas , DNA Viral/sangue , HIV-1/isolamento & purificação , Hepacivirus/isolamento & purificação , Vírus da Hepatite B/isolamento & purificação , RNA Viral/sangue , Centros de Atenção Terciária/normas , Adolescente , Adulto , Doadores de Sangue , Coleta de Amostras Sanguíneas , HIV-1/genética , Hepacivirus/genética , Vírus da Hepatite B/genética , Humanos , Pessoa de Meia-Idade , Adulto Jovem
2.
Toxicol Lett ; 139(1): 45-54, 2003 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-12595157

RESUMO

Turmeric, widely used in food and medicine has been shown to prevent benzo(a)pyrene [B(a)P] or dimethylbenz(a)anthracene (DMBA)-induced forestomach, skin and mammary tumors in mice and/or rats. In this study we examine the modulatory effects of turmeric on nitrosodiethylamine (NDEA)-induced hepatocarcinogenesis in rats. Female Wistar rats were administered NDEA (200 ppm) through drinking water (5 days per week) for 4 weeks. Control and/or NDEA-treated rats received 0, 0.2, 1.0 or 5.0% turmeric diet (w/w) either before (2 weeks), during (4 weeks) and after NDEA exposure (10 weeks) or starting from 24 h after NDEA exposure for 10 weeks. NDEA-treated rats receiving 1 or 5% turmeric before, during and after carcinogen exposure showed significant decrease in number of gamma glutamyl transpeptidase (GGT) positive foci measuring >500 or >1000 microm and decrease in the incidence of NDEA-induced focal dysplasia (FD) and hepatocellularcarcinomas. Decrease in the number of GGT positive foci measuring >1000 microm was also observed in NDEA-treated rats receiving 0.2% turmeric, although no decrease in tumor incidence was noted. On the other hand, similar levels of turmeric treatment (0.2, 1 and 5%) after exposure to NDEA did not show any protective effects. The underlying mechanism(s) of chemoprevention of NDEA-induced hepatocarcinogenesis need to be explored.


Assuntos
Curcuma , Dieta , Dietilnitrosamina/antagonistas & inibidores , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/prevenção & controle , Extratos Vegetais/farmacologia , Animais , Anticarcinógenos/administração & dosagem , Anticarcinógenos/farmacologia , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Incidência , Fígado/patologia , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Ratos Wistar , Rizoma/química
3.
Food Chem Toxicol ; 39(6): 541-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11346483

RESUMO

To study the mechanism(s) of turmeric-mediated chemoprevention and to compare the chemopreventive efficacy of turmeric/curcumin(s) against benzo[a]pyrene (B(a)P) and 4-methylnitrosamino-1-(3-pyridyl)-1-butanone (NNK, a tobacco-specific carcinogen), the effects of turmeric/curcumin (C), demethoxycurcumin (dmC), bis-demethoxycurcumin (bdmC) and phenyl and phenethyl-isothiocyanates (PITC and PEITC) on the dealkylation of ethoxyresorufin (ER), methoxyresorufin (MR) and pentoxyresorufin (PR) by rat liver microsomes (in vitro) were studied. These reactions are predominantly mediated by cytochrome P450 (CYP450) isozymes 1A1, 1A2 and 2B1, respectively. In vitro incubation of rat liver microsomes with each of the compounds--C, dmC, bdmC, PITC and PEITC--showed a dose-dependent decrease in carbon monoxide binding to microsomes and also showed a dose-dependent inhibition of CYP 1A1, 1A2 and 2B1 activity, as judged by a decrease in formation of resorufin from respective biochemical probes used. Both the isothiocyanates inhibited activity of CYP 2B1 more readily than that of CYP 1A1/1A2. Significantly lower concentrations of curcumin(s) than isothiocyanates achieved 50% inhibition of activity of CYP 1A1 and 1A2, while concentrations of C (4 microM), bdmC (2.5 microM) required to inhibit CYP 2B1 were slightly higher than that of PEITC (1.3 microM), suggesting curcumin(s) to be effective inhibitors of CYP 2B1 as well. Pretreatment of rats with 1% turmeric through the diet resulted in a significant decrease in induction of B(a)P-induced CYP 1A1 and 1A2 and phenobarbitone (PB)-induced CYP 2B1 in liver, lung and stomach, although the extent of the decrease was different. These results suggest that turmeric/curcumin(s) as in the case of isothiocyanate, PEITC, are likely to inhibit activation of carcinogens metabolized by CYP450 isozymes, namely, CYP 1A1, 1A2 and 2B1.


Assuntos
Curcumina/farmacologia , Inibidores das Enzimas do Citocromo P-450 , Inibidores Enzimáticos/farmacologia , Isoenzimas/antagonistas & inibidores , Microssomos Hepáticos/enzimologia , Animais , Células Cultivadas , Quimioprevenção , Citocromo P-450 CYP1A1/antagonistas & inibidores , Inibidores do Citocromo P-450 CYP1A2 , Citocromo P-450 CYP2B1/antagonistas & inibidores , Sistema Enzimático do Citocromo P-450/metabolismo , Relação Dose-Resposta a Droga , Isoenzimas/metabolismo , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
4.
J Environ Pathol Toxicol Oncol ; 20(1): 59-63, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11215708

RESUMO

Turmeric and/or its main coloring component, curcumin (diferuloylmethane), have been shown to inhibit benzo(a)pyrene [B(a)P]-induced forestomach papillomas in mice. However, the mechanisms of turmeric-mediated chemoprevention are not well understood. To study the mechanisms of turmeric-mediated chemoprevention, we investigated the effects of turmeric feeding on the activities of isozymes of cytochrome P-450 (CYP450)--namely, ethoxyresorufin O-deethylase (EROD, CYP1A1) and methoxyresorufin O-demethylase (MROD, CYP1A2)--which are predominantly involved in the metabolism of B(a)P. We determined the activities of EROD and MROD by monitoring the formation of resorufin from respective substrates in the presence of microsomal proteins obtained from tissues of control, 1% turmeric, 1 mg B(a)P, and 1% turmeric + 1 mg B(a)P-fed Swiss mice. The results indicate that the administration of turmeric through diet significantly inhibited the activities of both EROD and MROD in forestomach (target organ), liver, and lung. In vitro studies employing curcumin, demethoxycurcumin, and bis-demethoxycurcumin suggest that curcumins are the inhibitors in turmeric. Inhibition of B(a)P metabolizing phase I enzymes (EROD, MROD) may be at least in part one of the possible modes of chemopreventive action of turmeric/curcumin.


Assuntos
Benzo(a)pireno/farmacologia , Curcumina/farmacologia , Citocromo P-450 CYP1A1/biossíntese , Sistema Enzimático do Citocromo P-450/biossíntese , Oxirredutases/biossíntese , Animais , Masculino , Camundongos , Oxazinas/metabolismo
5.
Indian J Med Res ; 106: 242-6, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9378531

RESUMO

Gene frequencies have been calculated from 6334 blood donors who were tested at a referral hospital in north India, for ABO & Rh and from > 350 donors who were tested for other blood groups. The Hardy Weinberg equation for 2 allel systems and the Bernstein method for 3 or more allel systems have been employed for calculating gene frequencies. The predominance of blood group B (37.39%), Rh D negative frequency of 4.63 per cent, predominance of M gene (0.6383) and M s haplotype (0.4464) and S gene frequency below 0.3 (0.2069) agrees with earlier data. The new findings include the presence of the allels Fy (a-b-) (0.44%) in the Duffy group, S- s- (1.16%) in the Ss group and JK (a-b-) (0.54%) in the Kidd blood group system. These have not been reported in the Indian population.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Frequência do Gene , Humanos , Índia
6.
Phytochemistry ; 34(3): 861-2, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7764156

RESUMO

Clemontanoside F, a new triterpenic bisglycoside from the roots of Clematis montana, has been characterized as 3-O-beta-D-glucopyranosyl-28-O-beta-D-galactopyranosyl(1-->6)-[alpha-L-r hamnopyranosyl (1-->)]-beta-D-glucopyranosyl-3beta-hydroxy-olean-12-en-28- oate.


Assuntos
Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/isolamento & purificação , Plantas/química , Saponinas/isolamento & purificação , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Ácido Oleanólico/química , Saponinas/química
7.
Phytochemistry ; 33(3): 671-3, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7763801

RESUMO

Clemontanoside-C, a new hederagenin-based saponin isolated from the stems of Clematis montana, was identified by chemical and spectroscopic methods as hederagenin-3-O-alpha-L-arabinopyranosyl (1-3)-alpha-L-rhamnopyranosyl (1-2)-alpha-L-arabinopyranoside.


Assuntos
Ácido Oleanólico/análogos & derivados , Plantas/química , Saponinas/isolamento & purificação , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Estrutura Molecular , Ácido Oleanólico/química , Ácido Oleanólico/isolamento & purificação , Saponinas/química , Triterpenos/química , Triterpenos/isolamento & purificação
10.
J Chromatogr ; 160(1): 239-45, 1978 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-730791

RESUMO

A method is described for converting thiol metabolites of azathioprine and 6-mercaptopurine into phenyl mercury derivatives. Separation of these derivatives was performed by chromatography on silica thin layers and they were detected by low temperature (--196 degrees) fluorescence. The parent compounds were regenerated on the chromatogram by spraying with 2 N HC1 and these were detected by low temperature fluorescence. Mercury was also detected in spots by spraying with dithizone. The method provides a simple solution to the problem of oxidation of thiol compounds during isolation procedures.


Assuntos
Azatioprina/metabolismo , Mercaptopurina/metabolismo , Compostos de Sulfidrila/análise , Azatioprina/isolamento & purificação , Cromatografia em Camada Fina , Mercaptopurina/isolamento & purificação , Compostos de Fenilmercúrio/análise , Temperatura
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