Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Ann Med ; 45(1): 37-50, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22413912

RESUMO

Nearly half of all heart failure (HF) patients have diastolic HF (DHF) or clinical HF with normal or near-normal left ventricular ejection fraction (LVEF). Although the terminology has not been clearly defined, it is increasingly being referred to as HF with preserved ejection fraction (HFPEF). The prevalence of HFPEF increases with age, especially among older women. Identifying HFPEF is important because the etiology, pathogenesis, prognosis, and optimal management may differ from that for systolic HF (SHF) or HF with reduced ejection fraction. The clinical presentation of HF is similar for both SHF and HFPEF. As in SHF, HFPEF is a clinical diagnosis. Once a clinical diagnosis of HF has been made, the presence of HFPEF can be established by confirming a normal or near-normal LVEF, often by an echocardiogram. HFPEF is often associated with a history of hypertension, concentric left ventricular hypertrophy, vascular stiffness, and left ventricular diastolic dysfunction. As in SHF, HFPEF is also associated with poor outcomes. While therapies with angiotensin-converting enzyme inhibitors and beta-blockers improve outcomes in SHF, there is currently no such evidence of their benefits in older HFPEF patients. In this review recent advances in the diagnosis and management of HFPEF in older adults are discussed.


Assuntos
Envelhecimento/fisiologia , Insuficiência Cardíaca Diastólica/diagnóstico , Insuficiência Cardíaca Diastólica/terapia , Volume Sistólico , Função Ventricular Esquerda , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Biomarcadores Farmacológicos/sangue , Terapia de Ressincronização Cardíaca , Diuréticos/uso terapêutico , Ecocardiografia , Eletrocardiografia , Terapia Genética , Insuficiência Cardíaca Diastólica/etiologia , Insuficiência Cardíaca Diastólica/fisiopatologia , Humanos
2.
World J Gastroenterol ; 13(48): 6538-48, 2007 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-18161924

RESUMO

AIM: To investigate the chemopreventive efficacy of the Indian medicinal plant Acanthus ilicifolius L Acanthaceae in a transplantable Ehrlich ascites carcinoma (EAC)-bearing murine model. METHODS: Male Swiss albino mice were divided into four groups: Group A was the untreated normal control; Group B was the EAC control mice group that received serial, intraperitoneal (ip) inoculations of rapidly proliferating 2 x 10(5) viable EAC cells in 0.2 mL of sterile phosphate buffered saline; Group C was the plant extract-treated group that received the aqueous leaf extract (ALE) of the plant at a dose of 2.5 mg/kg body weight by single ip injections, once daily for 10, 20 and 30 consecutive days following tumour inoculation (ALE control); and Group D was the EAC + ALE-treatment group. The chemopreventive potential of the ALE was evaluated in a murine model by studying various biological parameters and genotoxic markers, such as tumour cell count, mean survival of the animals, haematological indices, hepatocellular histology, immunohistochemical expression of liver metallothionein (MT) protein, sister-chromatid exchanges (SCEs), and DNA alterations. RESULTS: Treatment of the EAC-bearing mice with the ALE significantly (P < 0.001) reduced viable tumour cell count by 68.34% (228.7 x 10(6) +/- 0.53) when compared to EAC control mice (72.4 x 10(6) +/- 0.49), and restored body and organ weights almost to the normal values. ALE administration also increased (P < 0.001) mean survival of the hosts from 35 +/- 3.46 d in EAC control mice to 83 +/- 2.69 d in EAC + ALE-treated mice. Haematological indices also showed marked improvement with administration of ALE in EAC-bearing animals. There was a significant increase in RBC count (P < 0.001), hemoglobin percent (P < 0.001), and haematocrit value (P < 0.001) from 4.3 +/- 0.12, 6.4 +/- 0.93, and 17.63 +/- 0.72 respectively in EAC control mice to 7.1 +/- 0.13, 12.1 +/- 0.77, and 30.23 +/- 0.57 respectively in EAC + ALE-treated group, along with concurrent decrement (P < 0.001) in WBC count from 18.8 +/- 0.54 in EAC control to 8.4 +/- 0.71 in EAC + ALE. Furthermore, treatment with ALE substantially improved hepatocellular architecture and no noticeable neoplastic lesions or foci of cellular alteration were observed. Daily administration of the ALE was found to limit liver MT expression, an important marker of cell proliferation with concomitant reduction in MT immunoreactivity (62.25 +/- 2.58 vs 86.24 +/- 5.69, P < 0.01). ALE was also potentially effective in reducing (P < 0.001) the frequency of SCEs from 14.94 +/- 2.14 in EAC control to 5.12 +/- 1.16 in EAC + ALE-treated group. Finally, in comparison to the EAC control, ALE was able to suppress in vivo DNA damage by abating the generations of 'tailed' DNA by 53.59% (98.65 +/- 2.31 vs 45.06 +/- 1.14, P < 0.001), and DNA single-strand breaks (SSBs) by 38.53% (3.14 +/- 0.31 vs 1.93 +/- 0.23, P < 0.01) in EAC-bearing murine liver. CONCLUSION: Our data indicate that, ALE is beneficial in restoring haematological and hepatic histological profiles and in lengthening the survival of the animals against the proliferation of ascites tumour in vivo. Finally, the chemopreventive efficacy of the ALE is manifested in limiting MT expression and in preventing DNA alterations in murine liver. The promising results of this study suggest further investigation into the chemopreventive mechanisms of the medicinal plant A. ilicifolius in vivo and in vitro.


Assuntos
Acanthaceae , Carcinoma de Ehrlich/genética , Carcinoma de Ehrlich/patologia , Transplante de Células/patologia , Dano ao DNA/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Quebras de DNA de Cadeia Simples/efeitos dos fármacos , Dano ao DNA/genética , DNA de Neoplasias/efeitos dos fármacos , DNA de Neoplasias/genética , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fígado/metabolismo , Fígado/patologia , Masculino , Metalotioneína/metabolismo , Camundongos , Troca de Cromátide Irmã/efeitos dos fármacos
3.
Eur J Cancer Prev ; 16(4): 363-71, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17554210

RESUMO

This is an extensive study in a defined initiation-promotion hepatocellular carcinoma model of hepatocarcinogenesis (in rats) in which many important marker enzymes and isoenzymes and 8-hydroxydeoxyguanosine formation have been studied together with two very important cellular proliferating genes, insulin-like growth factor II and c-raf.1, known for their role in hepatocellular cancer development. Experiments were carried out on hepatic tissues of male Sprague-Dawley rats. Variations in different enzyme/isoenzyme activities/contents/expression pattern and 8-hydroxydeoxyguanosine-positive cells were studied. Insulin-like growth factor II and c-raf.1 gene expressions were monitored. A direct shift with increase in size and numbers of lesions was found to occur in different experimental groups. In this study, glutathione peroxidase (1.14 and 1.46-fold) and reduced triphosphopyridine nucleotide (TPNH)-cytochrome-c-reductase (1.94 and 2.94-fold) activities, cytochrome b5 (1.57 and 3.28-fold) and P-450 contents (1.45 and 1.22-fold), glutathione content (1.27 and 1.45-fold) and superoxide dismutase and catalase (1.16 and 1.39-fold) activities in group A animals were found to be lower than those in initiation and promotion studies, respectively. 8-Hydroxydeoxyguanosine-positive nuclei count showed that oxidative damage of nuclear DNA enhanced with the progress of the disease. The insulin-like growth factor II expression was found to be predominant in hepatocellular carcinoma and in early preneoplastic lesions. Unlike insulin-like growth factor II, c-raf.1 expression was located in the late basophilic lesions associated with hepatocellular carcinoma. During the various stages of the development of hepatocellular carcinoma, the enzymes played a significant role in metabolizing carcinogens and thereby scavenging various toxic metabolites or free radicals produced. A sequence of cellular changes starting from the appearance of glycogen storage foci to basophilic foci leading to hepatocellular carcinoma via mixed cell foci varied the activity/content or expression pattern of the enzymes and isoenzymes and in 8-hydroxydeoxyguanosine formation. It has been established that c-raf.1-induced signaling pathways activated by insulin-like growth factor II is implicated in the late stage of development of cancer.


Assuntos
Antioxidantes/metabolismo , Carcinoma Hepatocelular/patologia , Desoxiguanosina/análogos & derivados , Inativação Metabólica , Fator de Crescimento Insulin-Like II/genética , Fígado/enzimologia , Proteínas Proto-Oncogênicas c-raf/genética , 8-Hidroxi-2'-Desoxiguanosina , Animais , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/genética , Núcleo Celular/metabolismo , Desoxiguanosina/biossíntese , Regulação Neoplásica da Expressão Gênica , Glucose-6-Fosfatase/metabolismo , Glutationa/metabolismo , Isoenzimas/metabolismo , Fígado/patologia , Masculino , Lesões Pré-Cancerosas/enzimologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Ratos , Ratos Sprague-Dawley
4.
World J Gastroenterol ; 10(9): 1268-75, 2004 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15112340

RESUMO

AIM: To investigate the chemopreventive effects of 1alpha, 25-dihydroxyvitamin D(3) in diethylnitrosamine induced, phenobarbital promoted rat hepatocarcinogenesis. METHODS: The rats were randomly divided into 6 different groups (A-F). Groups A, C and E rats received a single intraperitoneal (i.p.) injection of diethylnitrosamine (DEN) at a dose of 200 mg/kg body mass in 9 g/L NaCl solution at 4 wk of age, while group B served as normal vehicle control received normal saline once. After a brief recovery of 2 wk, all the DEN treated rats were given phenobarbital (PB) at 0.5 g/L daily in the basal diet till wk 20. Group A was DEN control. Treatment of 1alpha, 25-(OH)2D3 in group C was started 4 wk prior to DEN injection and continued thereafter till wk 20 at a dose of 0.3 microg/100 microL propylene glycol per one single dose (os) twice a week. Group E received the treatment of 1alpha, 25-(OH)2D3 at the same dose mentioned as above for 15 wk. The rats in group D and F received 1alpha, 25-(OH)2D3 alone as in group C without DEN injection. RESULTS: The comet assay showed statistically higher mean values for length to width ratios (L: W) of DNA mass and tailed cells (P<0.01; P<0.01 respectively) in DEN treated rats as compared to their normal controls. Continuous supplementation of 1alpha, 25-dihydroxyvitaminD2 showed a significant (P<0.01) decrease in L:W ratio of DNA mass tailed cells. Furthermore, 1alpha, 25-(OH)2D3 supplementations elevated the super oxide dismutase (SOD) activity, hepatic malondialdehyde (MDA) level, reduced glutathione (GSH) and glutathione S-transferase (GST) activity (P<0.01, P<0.05, P<0.05 and P<0.05 respectively). As an endpoint marker histological changes were observed to establish the chemopreventive effects of 1alpha, 25-dihydroxyvitaminD2. CONCLUSION: Supplementations of 1alpha, 25-(OH)2D3 has a marked protection against hepatic nodulogenesis, antioxidant enzymes and DNA damages in DEN induced rat hepatocarcinogenesis promoted by phenobarbital.


Assuntos
Alquilantes/toxicidade , Anticonvulsivantes/toxicidade , Antioxidantes/metabolismo , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas Experimentais/induzido quimicamente , Fenobarbital/toxicidade , Vitamina D/análogos & derivados , Vitamina D/metabolismo , Animais , Carcinógenos , Ensaio Cometa , Dano ao DNA , Dieta , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
5.
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA