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1.
Artigo em Inglês | MEDLINE | ID: mdl-29755412

RESUMO

Progesterone elevation (PE) during the late follicular phase of controlled ovarian stimulation in fresh embryo transfer in vitro fertilization (IVF)/intracytoplasmic sperm injection cycles has been claimed to be associated with decreased pregnancy rates. However, the evidence is not unequivocal, and clinicians still have questions about the clinical validity of measuring P levels during the follicular phase of stimulated cycles. We reviewed the existing literature aimed at answering four relevant clinical questions, namely (i) Is gonadotropin type associated with PE during the follicular phase of stimulated cycles? (ii) Is PE on the day of human chorionic gonadotropin (hCG) associated with negative fresh embryo transfer IVF/intracytoplasmic sperm injection (ICSI) cycles outcomes in all patient subgroups? (iii) Which P thresholds are best to identify patients at risk of implantation failure due to PE in a fresh embryo transfer? and (iv) Should a freeze all policy be adopted in all the cycles with PE on the day of hCG? The existing evidence indicates that late follicular phase progesterone rise in gonadotropin releasing analog cycles is mainly caused by the supraphysiological stimulation of granulosa cells with exogenous follicle-stimulating hormone. Yet, the type of gonadotropin used for stimulation seems to play no significant role on progesterone levels at the end of stimulation. Furthermore, PE is not a universal phenomenon with evidence indicating that its detrimental consequences on pregnancy outcomes do not affect all patient populations equally. Patients with high ovarian response to control ovarian stimulation are more prone to exhibit PE at the late follicular phase. However, in studies showing an overall detrimental effect of PE on pregnancy rates, the adverse effect of PE on endometrial receptivity seems to be offset, at least in part, by the availability of good quality embryo for transfer in women with a high ovarian response. Given the limitations of the currently available assays to measure progesterone at low ranges, caution should be applied to adopt specific cutoff values above which the effect of progesterone rise could be considered detrimental and to recommend "freeze-all" based solely on pre-defined cutoff points.

2.
Chemosphere ; 144: 2238-46, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26598992

RESUMO

Mono-hydroxylated polychlorinated biphenyls (OH-PCBs) are found in human biological samples and lack of data on their potential estrogenic activity has been a source of concern. We have extended our previous in silico 2D QSAR study through the application of advance techniques such as docking and 3D QSAR to gain insights into their estrogen receptor (ERα) binding. The results support our earlier findings that the hydroxyl group is the most important feature on the compounds; its position, orientation and surroundings in the structure are influential for the binding of OH-PCBs to ERα. This study has also revealed the following additional interactions that influence estrogenicity of these chemicals (a) the aromatic interactions of the biphenyl moieties with the receptor, (b) hydrogen bonding interactions of the p-hydroxyl group with key amino acids ARG394 and GLU353, (c) low or no electronegative substitution at para-positions of the p-hydroxyl group, (d) enhanced electrostatic interactions at the meta position on the B ring, and (e) co-planarity of the hydroxyl group on the A ring. In combination the 2D and 3D QSAR approaches have led us to the support conclusion that the hydroxyl group is the most important feature on the OH-PCB influencing the binding to estrogen receptors, and have enhanced our understanding of the mechanistic details of estrogenicity of this class of chemicals. Such in silico computational methods could serve as useful tools in risk assessment of chemicals.


Assuntos
Receptor alfa de Estrogênio/química , Estrogênios não Esteroides/toxicidade , Bifenilos Policlorados/toxicidade , Xenobióticos/toxicidade , Sítios de Ligação , Simulação por Computador , Bases de Dados de Proteínas , Estrogênios não Esteroides/química , Genes Reporter/efeitos dos fármacos , Humanos , Ligação de Hidrogênio , Hidroxilação , Ligantes , Simulação de Acoplamento Molecular , Bifenilos Policlorados/química , Ligação Proteica , Relação Quantitativa Estrutura-Atividade , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Técnicas do Sistema de Duplo-Híbrido , Xenobióticos/química
3.
Indian J Pharmacol ; 45(3): 232-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23833364

RESUMO

OBJECTIVE: To evaluate the nephroprotective effect of methanolic extract of Hygrophila spinosa (HSME) (Acanthaceae) in (CP)-induced acute renal failure in rats. MATERIALS AND METHODS: HSME (250 mg/kg and 500 mg/kg body weight), were administered orally to male wistar albino rats.CP was used to induce acute renal failure. The parameters studied included blood urea and serum creatinine and malondialdehyde (MDA), reduced glutathione (GSH), catalase (CAT), superoxide dismutase (SOD) and GSH peroxidase activities. Histopathological examination was also carried out. RESULTS: The results revealed that HSME pretreatment signiûcantly reduced blood urea and serum creatinine levels elevated by CP administration. Furthermore, HSME signiûcantly attenuated CP-induced increase in MDA and decrease in reduced GSH, and CAT and SOD and GSH peroxidase activities in renal cortical homogenates. Additionally, histopathological examination showed that HSME markedly ameliorated CP-induced renal tubular necrosis. CONCLUSION: The results indicate that the aerial parts of H. spinosa are endowed with nephroprotective activity.


Assuntos
Acanthaceae , Injúria Renal Aguda/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Substâncias Protetoras/uso terapêutico , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Animais , Antineoplásicos , Catalase/metabolismo , Cisplatino , Creatinina/sangue , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Túbulos Renais/patologia , Masculino , Malondialdeído/metabolismo , Fitoterapia , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Ureia/sangue
4.
Indian J Pharmacol ; 44(5): 639-42, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23112429

RESUMO

OBJECTIVE: Hygrophila spinosa (Acanthaceae) is traditionally used to treat urinary calculi. The present study aimed to evaluate the antiurolithiatic activity of methanolic extract of Hygrophila spinosa (Acanthaceae) in ethylene glycol induced nephrolithiasic rats. MATERIALS AND METHODS: Methanolic extract of Hygrophila spinosa (HSME) (250 and 500 mg/ kg body weight) was administered orally to male Wistar albino rats. Ethylene glycol (EG) was used to induce nephrolithiasis. The parameters studied included water intake, urinary volume, urinary pH, urinary and kidney oxalate and calcium, urinary magnesium and serum uric acid. RESULTS: Ethylene glycol feeding resulted in hyperoxaluria as well as increased renal excretion of calcium and serum uric acid along with decreased excretion of urinary magnesium. Treatment with HSME significantly reduced the elevated urinary oxalate, urinary calcium and serum uric acid with increase in reduced urinary magnesium. Ethylene glycol feeding also resulted in increased levels of calcium and oxalate in kidney which was decreased after the treatment with HSME. The increased deposition of stone forming constituents in the kidneys of ethylene glycol treated rats was significantly lowered by treatment with HSME. CONCLUSION: The results indicate that the aerial parts of Hygrophila spinosa are endowed with antiurolithiatic activity, thereby justifying its traditional claim.


Assuntos
Acanthaceae , Etilenoglicol/toxicidade , Nefrolitíase/induzido quimicamente , Nefrolitíase/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Animais , Feminino , Masculino , Nefrolitíase/metabolismo , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Wistar , Resultado do Tratamento
5.
Med Chem ; 8(2): 299-307, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22385182

RESUMO

Anticoagulants are used to prevent the formation and extension of blood clots in various disorders as prophylactic agents for thrombo-embolic disorders. Designing of specific inhibitors against molecular targets that play a pivotal role in the coagulation cascade is indispensable. Clotting Factor Xa is one such attractive target for the design of new oral anticoagulants because of the unique role factor Xa plays in the coagulation cascade as a connection between the extrinsic and intrinsic pathways. Application of computational techniques in drug discovery process helps in identifying parameters which can lead to achieve better pharmacological profile. The docking interactions and QSAR studies performed on series of 4-methy-3-(6-[phenyl methylene] amino} pyridine-3-yl)-2H chromen-2-one derivatives provide significant insights for designing of better ligands as anticoagulants.


Assuntos
Aminopiridinas/farmacologia , Anticoagulantes/farmacologia , Inibidores dos Fatores de Coagulação Sanguínea/farmacologia , Cumarínicos/farmacologia , Inibidores do Fator Xa , Aminopiridinas/síntese química , Aminopiridinas/química , Anticoagulantes/síntese química , Anticoagulantes/química , Inibidores dos Fatores de Coagulação Sanguínea/síntese química , Inibidores dos Fatores de Coagulação Sanguínea/química , Cumarínicos/síntese química , Cumarínicos/química , Descoberta de Drogas , Modelos Lineares , Modelos Moleculares , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade
6.
Antivir Chem Chemother ; 22(3): 95-105, 2011 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-22095518

RESUMO

Highly active antiretroviral therapy (HAART) significantly decreases plasma viral load, increases CD4+ T-cell counts in HIV-1-infected patients and has reduced progression to AIDS in developed countries. However, adverse side effects, and emergence of drug resistance, mean there is still a demand for new anti-HIV agents. The HIV integrase (IN) is a target that has been the focus of rational drug design over the past decade. In 2007, raltegravir was the first IN inhibitor approved by the US Food and Drug Administration for antiretroviral combination therapy, while another IN inhibitor, elvitegravir, is currently in Phase III clinical trials. This article reviews the development and resistance profiling of small molecule HIV-1 IN inhibitors.


Assuntos
Descoberta de Drogas , Inibidores de Integrase de HIV/química , Inibidores de Integrase de HIV/farmacologia , Integrase de HIV/metabolismo , Farmacorresistência Viral/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Inibidores de Integrase de HIV/efeitos adversos , Humanos
7.
Sci Pharm ; 79(3): 601-14, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21886906

RESUMO

Simvastatin is used in treatment of hypercholesterolemia because it regulates cholesterol synthesis as a result of its ß-hydroxy acid acting as an inhibitor of 3-hydroxy-methylglutaryl coenzyme A (HMG-CoA). The present communication deals with synthesis, characterization and development of accurate, precise and sensitive Reverse Phase High Performance Liquid Chromatography (RP-HPLC) method for simultaneous estimation of simvastatin and its synthetic impurities. The impurities methyl ether and ß-hydroxy acid of simvastatin were synthesized in the laboratory and characterized by MS, NMR and FT-IR spectroscopy. The separation of simvastatin and its impurities was carried out on an isocratic JASCO RP-HPLC system using KYA TECH HIQ SIL C(18) column (150 × 4.6 mm internal diameter, particle size 5 µm) operating at ambient temperature using acetonitrile:water (80:20 v/v) with 0.1% orthophosphoric acid as mobile phase. The method developed for HPLC analysis of three impurities along with simvastatin was validated using ICH Q2B (R1) guidelines and it complied with these guidelines. The results of analysis were found to be in the range of 98.14% to 101.89% for all analytes with acceptable accuracy and precision. The method can be used for detection and quantification of synthetic impurities in bulk or formulations of simvastatin.

8.
J Diabetes Complications ; 25(2): 129-36, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20462773

RESUMO

Erectile dysfunction (ED) is defined as the inability of the male to attain and maintain erection of penis sufficient to permit satisfactory sexual intercourse. Prevalence of impotence in diabetic men is ≥50%. The pathophysiology of diabetes-induced erectile dysfunction (DIED) is multifactorial and no single etiology is at the forefront. The proposed mechanisms of erectile dysfunction in diabetic patients includes elevated advanced glycation end-products, increased levels of oxygen free radicals, impaired nitric oxide synthesis, increased endothelin B receptor binding sites and up-regulated RhoA/Rho-kinase pathway, neuropathic damage and impaired cyclic guanosine monophosphate (cGMP)-dependent protein kinase-1. The treatment of DIED is multimodal. Treatment of the underlying hyperglycemia and comorbidities is of utmost importance to prevent or halt the progression of disease. Oral medications are considered as the first line therapy for management of DIED. If oral agents cannot be used or have insufficient efficacy despite appropriate dosing and education, second-line treatments should be addressed. When there is lack of efficacy or when there is dissatisfaction with other modalities, penile prostheses are often the best alternative for ED and are considered as the third line therapy for DIED. Future strategies in the evolution of the treatment of DIED are aimed at correcting or treating the underlying mechanisms of DIED.


Assuntos
Complicações do Diabetes/epidemiologia , Complicações do Diabetes/etiologia , Complicações do Diabetes/terapia , Disfunção Erétil/epidemiologia , Disfunção Erétil/etiologia , Disfunção Erétil/terapia , Animais , Complicações do Diabetes/metabolismo , Neuropatias Diabéticas/complicações , Neuropatias Diabéticas/epidemiologia , Neuropatias Diabéticas/metabolismo , Neuropatias Diabéticas/terapia , Disfunção Erétil/metabolismo , Produtos Finais de Glicação Avançada/efeitos adversos , Produtos Finais de Glicação Avançada/metabolismo , Saúde , Humanos , Masculino , Óxido Nítrico/biossíntese , Sexualidade/fisiologia
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