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51.
Mutations of p53 Tumor Suppressor Gene, Apoptosis, and Proliferation in Intrahepatic Cholangiocellular Carcinoma of the Liver 总被引:4,自引:0,他引:4
Tannapfel A Weinans L Geissler F Schütz A Katalinic A Köckerling F Hauss J Wittekind C 《Digestive diseases and sciences》2000,45(2):317-324
This study was performed to examine the correlation between mutations of the p53 tumor suppressor gene, the occurrence of apoptosis, and proliferation in cholangiocellular carcinoma of the liver. The results obtained were compared with pathohistological stage (according to UICC) and grade and with disease related survival rate. In 41 curatively (R0–) resected intrahepatic cholangiocellular carcinomas, the status of the p53 gene was determined by direct sequencing of exons 4–9 and immunohistochemically. Apoptosis was assessed using the in situ end labeling (ISEL) technique in combination with morphological criteria. Proliferation was analyzed by immunohistochemistry of MIB-1 (Ki-67), Proliferating cell nuclear antigen (PCNA), and silver-stained nucleolar organizer regions (AgNOR). The results obtained were compared with pathohistological stage (according to UICC), grade, several other histopathological factors, and survival rate. Mutations of p53 were detected in 15/41 carcinomas examined (37%). The most common change was a GC and CT transition, changing the hot spot amino acid determined by exons 4–8. Of these 15 tumors, 14 were also p53-positive by immunohistochemistry. In each carcinoma examined, we could demonstrate MIB-1, PCNA, and AgNOR dots and also apoptotic cells in variable proportions. The proliferation markers showed a significant correlation among themselves. In univariate survival analysis, the extent of the primary tumor, lymph node status, grade, and p53 were significant factors influencing patient survival. Performing multivariate Cox regression survival analysis, however, only the extent of primary tumor and lymph node status had an independent prognostic impact. Apoptosis was not related to patient prognosis or to other parameters examined. In conclusion, these results indicated that p53 could serve as an additional prognostic parameter that could provide auxiliary information for patient outcome. However, tumor stage and lymph node involvement were the strongest prognostic factors. We failed to establish apoptosis or other pathological parameters as factors predicting the prognosis of patients with cholangiocellular carcinoma. 相似文献
52.
Keith C. Ferdinand MD ; Elijah Sounders MD 《Journal of clinical hypertension (Greenwich, Conn.)》2006,8(S1):21-30
Almost one third of adults in the United States have hypertension. Prevalence data among different racial or ethnic groups indicate that a disproportionate number of African Americans have hypertension compared with non-Hispanic whites and Mexican Americans. Earlier onset of high blood pressure and greater severity of hypertension contribute to a greater burden of hypertensive target organ damage in African Americans and may be a factor in the shorter life expectancy of this population compared with white Americans. There is a clear need for improved management of hypertension in African Americans via therapeutic lifestyle interventions and pharmacotherapy. While there is some evidence that particular antihypertensive agent classes provide blood pressure-lowering advantages over others, there is no support for withholding agents of any one class. When given as monotherapy, diuretics and calcium channel blockers may be relatively more effective in lowering blood pressure in African Americans than β blockers, angiotensin-converting enzyme inhibitors, and angiotensin II receptor blockers. However, when combined with a diuretic, African Americans respond as well to these agents as other racial groups. Combination therapy using antihypertensive agents with differing modes of action provides additive antihypertensive efficacy and is well tolerated. Recent guidelines recommend combination therapy as the standard of care for patients with significant blood pressure elevation, especially those with diabetes mellitus and renal disease. These comorbidities are more common in African Americans and indicate the potential need for initial therapy with more than one agent or a combination of agents in one pill. 相似文献
53.
Cushman WC Neutel JM Saunders E Bakris GL Ferdinand KC Ofili EO Sowers JR Madder R Weber MA 《The American journal of geriatric cardiology》2008,17(1):27-36
Subgroup analysis of the Irbesartan/Hydrochlorothiazide Blood Pressure Reductions in Diverse Patient Populations (INCLUSIVE) trial evaluated the efficacy and safety of irbesartan/hydrochlorothiazide (HCTZ) fixed combinations in patients aged 65 years or older with uncontrolled systolic blood pressure (SBP) after >or= 4 weeks of antihypertensive monotherapy. The INCLUSIVE trial was a prospective, open-label, single-arm trial carried out in 119 sites. Of 844 patients completing placebo treatment, 212 were aged 65 years or older. Participants received treatment with placebo (4-5 weeks), HCTZ 12.5 mg (2 weeks), irbesartan/HCTZ 150/12.5 mg (8 weeks), and then irbesartan/HCTZ 300/25 mg (8 weeks). From baseline to week 18 (n=184, intent-to-treat population), mean change in SBP was -23.0+/-13.3 mm Hg (P<.001) and diastolic BP (DBP) was -10.9+/-7.7 mm Hg (P<.001). Mean SBP/DBP at study end was 134.0+/-14.7/75.1+/-8.4 mm Hg, and SBP, DBP, and SBP/DBP goal was achieved in 73%, 96%, and 72% of patients, respectively. Irbesartan/HCTZ combination therapy allowed SBP goal attainment in 73% of patients aged 65 years or older whose hypertension was previously uncontrolled with antihypertensive monotherapy. 相似文献
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Calhoun DA Jones D Textor S Goff DC Murphy TP Toto RD White A Cushman WC White W Sica D Ferdinand K Giles TD Falkner B Carey RM 《Hypertension》2008,51(6):1403-1419
Resistant hypertension is a common clinical problem faced by both primary care clinicians and specialists. While the exact prevalence of resistant hypertension is unknown, clinical trials suggest that it is not rare, involving perhaps 20% to 30% of study participants. As older age and obesity are 2 of the strongest risk factors for uncontrolled hypertension, the incidence of resistant hypertension will likely increase as the population becomes more elderly and heavier. The prognosis of resistant hypertension is unknown, but cardiovascular risk is undoubtedly increased as patients often have a history of long-standing, severe hypertension complicated by multiple other cardiovascular risk factors such as obesity, sleep apnea, diabetes, and chronic kidney disease. The diagnosis of resistant hypertension requires use of good blood pressure technique to confirm persistently elevated blood pressure levels. Pseudoresistance, including lack of blood pressure control secondary to poor medication adherence or white coat hypertension, must be excluded. Resistant hypertension is almost always multifactorial in etiology. Successful treatment requires identification and reversal of lifestyle factors contributing to treatment resistance; diagnosis and appropriate treatment of secondary causes of hypertension; and use of effective multidrug regimens. As a subgroup, patients with resistant hypertension have not been widely studied. Observational assessments have allowed for identification of demographic and lifestyle characteristics associated with resistant hypertension, and the role of secondary causes of hypertension in promoting treatment resistance is well documented; however, identification of broader mechanisms of treatment resistance is lacking. In particular, attempts to elucidate potential genetic causes of resistant hypertension have been limited. Recommendations for the pharmacological treatment of resistant hypertension remain largely empiric due to the lack of systematic assessments of 3 or 4 drug combinations. Studies of resistant hypertension are limited by the high cardiovascular risk of patients within this subgroup, which generally precludes safe withdrawal of medications; the presence of multiple disease processes (eg, sleep apnea, diabetes, chronic kidney disease, atherosclerotic disease) and their associated medical therapies, which confound interpretation of study results; and the difficulty in enrolling large numbers of study participants. Expanding our understanding of the causes of resistant hypertension and thereby potentially allowing for more effective prevention and/or treatment will be essential to improve the long-term clinical management of this disorder. 相似文献
57.
Sreekanth Vemulapalli Jamy Ard George L. Bakris Deepak L. Bhatt Alan S. Brown William C. Cushman Keith C. Ferdinand John M. Flack Jerome L. Fleg Barry T. Katzen John B. Kostis Suzanne Oparil Chet B. Patel Carl J. Pepine Ileana L. Piña Krishna J. Rocha-Singh Raymond R. Townsend Eric D. Peterson Robert M. Califf Manesh R. Patel 《American heart journal》2014
58.
Benedikt Bosbach Shayu Deshpande Ferdinand Rossi Jae-Hung Shieh Gunhild Sommer Elisa de Stanchina Darren R. Veach Joseph M. Scandura Katia Manova-Todorova Malcolm A. S. Moore Cristina R. Antonescu Peter Besmer 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(34):E2276
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