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151.
Dinucleotide repeats negatively modulate the promoter activity of Cyr61 and is unstable in hepatocellular carcinoma patients 总被引:4,自引:0,他引:4
Cyr61 is a secreted, cysteine-rich, heparin-binding protein that mediates diverse functions including extracellular matrix formation, differentiation, cell proliferation, adhesion, migration, survival, as well as angiogenesis and tumorigenesis. In this study, we found that Cyr61 gene expression is significantly downregulated in the tumors of hepatocellular carcinoma (HCC) patients. To elucidate its mechanism of gene regulation, we examined the promoter of Cyr61 which contains two long stretches of repeats, each comprising d(CA) dinucleotide repeats downstream of HNF3beta- and ATF-binding sites. We hypothesized that the d(CA) repeats may play an important role in regulating Cyr61 promoter activity and performed promoter reporter assays to examine this. We found that a greater number of d(CA) repeats resulted in significantly lower promoter activity of the Cyr61 gene in the KB3-1 and HepG2 cell lines, but not in the MCF-7 cell line. In addition, the d(CA) repeats, but not other random sequences, were found to be important for Cyr61 promoter activity. We further demonstrate that the ATF- and HNF3beta-binding sites upstream the d(CA) repeats positively and negatively modulate Cyr61 promoter activity, respectively. An examination of the d(CA) dinucleotide patterns in the Cyr61 promoter in HCC patients revealed that approximately 32% of these patients exhibited either loss of heterozygosity or somatic mosaicism in either the tumors, adjacent normal liver tissues or both. 相似文献
152.
Rodriguez-Galindo C Wofford M Castleberry RP Swanson GP London WB Fontanesi J Pappo AS Douglass EC 《Cancer》2005,103(4):850-857
BACKGROUND: Nasopharyngeal carcinoma (NPC) is rare in children, accounting for <1% of all cases. Treatment most commonly includes radiotherapy but long-term side effects of such treatment can produce devastating cosmetic and functional sequelae in children. Chemotherapy may help to decrease the radiotherapy dose and limit the side effects of local therapies. However, little is known regarding the chemosensitivity of NPC tumors in pediatric patients. METHODS: Patients with American Joint Committee on Cancer (AJCC) Stage I/II disease (Stratum 01) received irradiation only. Patients with AJCC Stage III/IV disease (Stratum 02) received 4 courses of preradiation chemotherapy comprising methotrexate (120 mg/m2) on Day 1, with cisplatin (100 mg/m2) 24 hours later, 5-fluorouracil 1000 mg/m2 per day as a continuous infusion for 3 days, and leucovorin 25 mg/m2 every 6 hours for 6 doses. Irradiation was given after chemotherapy and consisted of 50.4 gray (Gy) to the upper neck and 45.0 Gy to the lower neck, with a boost to the primary tumor and positive lymph nodes for a total dose of 61.2 Gy. RESULTS: One patient was enrolled in Stratum 01 and 16 evaluable patients were enrolled in Stratum 02. The median age of the patients was 13 years and 65% of the patients were black. All patients tested had evidence of Epstein-Barr virus infection. Two-thirds of the patients developed Grade 3-4 mucositis during chemotherapy. The overall response rate to induction chemotherapy was 93.7%. The overall 4-year event-free and overall survival rates (+/- the standard error) were 77%+/-12% and 75%+/-12%, respectively. CONCLUSIONS: The current study demonstrated that childhood NPC was sensitive to chemotherapy and that chemotherapy before irradiation was feasible. Future trials should investigate equivalent efficacy with a reduced radiotherapy dose. 相似文献
153.
London GM Marchais SJ Guérin AP Métivier F 《Current opinion in nephrology and hypertension》2005,14(6):525-531
PURPOSE OF REVIEW: Arterial calcification in chronic kidney disease (CKD) is associated with increased cardiovascular risk. The mechanisms responsible for arterial calcification include alterations of mineral metabolism and expression of mineral-regulating proteins. RECENT FINDINGS: Arterial calcification is similar to bone formation, involving differentiation of vascular smooth muscle cells (VSMCs) into phenotypically distinct osteoblast-like cells. Elevated phosphate and/or calcium trigger a concentration-dependent increase of calcium precipitates in VSMC in vitro. The calcification is initiated by VSMC release of membrane-bound matrix vesicles and formation of apoptotic bodies. The presence of serum prevents these changes, indicating the presence of calcification inhibitors. Arterial calcification occurs in two sites: the tunica intima and tunica media. Intimal calcification is a marker of atherosclerotic disease and is associated with arterial stenotic lesions. Medial calcification influences outcome by promoting arterial stiffening whose principal consequences are left-ventricular hypertrophy and altered coronary perfusion. Aortic stiffness is an independent predictor of all-cause and cardiovascular mortality in CKD patients. Age, duration of dialysis, smoking and diabetes are risk factors for the development of arterial calcification in end-stage renal disease. Oversuppression of parathyroid hormone and low bone turnover potentiate the development of arterial calcification. SUMMARY: Arterial disease in CKD patients is characterized by extensive calcification. Evidence has accumulated pointing to the active and regulated nature of the calcification process. Elevated phosphate and calcium may stimulate sodium-dependent phosphate cotransport involving osteoblast-like changes in cellular gene expression. Arterial calcification is responsible for stiffening of the arteries with increased left-ventricular afterload and abnormal coronary perfusion as the principal clinical consequences. 相似文献
154.
155.
BACKGROUND: Childhood exposure to environmental tobacco smoke has been extensively associated with childhood respiratory illness; fewer studies have addressed the effects on adults. METHODS: Childhood environmental tobacco smoke exposure in relation to chronic cough, phlegm, and asthma diagnosis was studied in never smokers from a cohort of Singaporeans of Chinese ethnicity aged 45-74 years at enrollment from 1993 to 1998. From 1999 to 2004 subjects were interviewed regarding environmental tobacco smoke exposure before and after the age of 18 and the presence and duration of current symptoms of chronic cough and phlegm production and asthma diagnosis. RESULTS: Among 35,000 never smokers, fewer had smoking mothers (19%) than fathers (48%). Although few subjects currently lived (20%) or worked (4%) with smokers, 65% reported living with a daily smoker before the age of 18 years. Living with a smoker before the age of 18 increased the odds of chronic dry cough (149 cases, odds ratio 2.1, 95% CI 1.4 to 3.3) and, to a lesser extent, phlegm, after adjustment for age, sex, dialect group, and current and past exposure to smokers at home and at work after the age of 18. Associations strengthened with higher numbers of smokers in childhood. There was no association with asthma or chronic bronchitis. There was evidence to suggest a stronger association among subjects with a lower adult intake of fibre which has previously been found to be protective for respiratory symptoms. CONCLUSIONS: In this large study of non-smokers, living with a smoker in childhood was associated with chronic dry cough and phlegm in adulthood, independent of later exposures to environmental tobacco smoke. 相似文献
156.
Circulating endothelial microparticles are associated with vascular dysfunction in patients with end-stage renal failure 总被引:13,自引:0,他引:13
Amabile N Guérin AP Leroyer A Mallat Z Nguyen C Boddaert J London GM Tedgui A Boulanger CM 《Journal of the American Society of Nephrology : JASN》2005,16(11):3381-3388
Endothelial dysfunction and arterial stiffness are major determinants of cardiovascular risk in patients with end-stage renal failure (ESRF). Microparticles are membrane fragments shed from damaged or activated cells. Because microparticles can affect endothelial cells, this study investigated the relationship between circulating microparticles and arterial dysfunction in patients with ESRF and identified the cellular origin of microparticles associated with these alterations. Flow cytometry analysis of platelet-free plasma from 44 patients with ESRF indicated that circulating levels of Annexin V+ microparticles were increased compared with 32 healthy subjects, as were levels of microparticles derived from endothelial cells (three-fold), platelets (16.5-fold), and erythrocytes (1.6-fold). However, when arterial function was evaluated noninvasively in patients with ESRF, only endothelial microparticle levels correlated highly with loss of flow-mediated dilation (r = -0.543; P = 0.004), increased aortic pulse wave velocity (r = 0.642, P < 0.0001), and increased common carotid artery augmentation index (r = 0.463, P = 0.0017), whereas platelet-derived, erythrocyte-derived, and Annexin V+ microparticle levels did not. In vitro, microparticles from patients with ESRF impaired endothelium-dependent relaxations and cyclic guanosine monophosphate generation, whereas microparticles from healthy subjects did not. Moreover, in vitro endothelial dysfunction correlated with endothelial-derived (r = 0.891; P = 0.003) but not platelet-derived microparticle concentrations. In fact, endothelial microparticles alone decreased endothelial nitric oxide release by 59 +/- 7% (P = 0.025). This study suggests that circulating microparticles of endothelial origin are tightly associated with endothelial dysfunction and arterial dysfunction in ESRF. 相似文献
157.
Goh BK Tan YM Ong HS Chui CH Ooi LL Chow PK Tan CE Wong WK 《World journal of surgery》2005,29(7):837-840
Intra-abdominal and retroperitoneal lymphangiomas are a rare, congenital malformations of the lymphatics, which are found
predominantly in children. The aim of this study is to evaluate the clinical features of this tumor, highlighting the differences
in adults and pediatric patients. We also evaluate the preoperative diagnosis, radiological features, surgical treatment,
and outcome of this rare condition. Between 1990 and 2004, 14 patients who underwent surgical resection of an intra-abdominal
lymphangioma were reviewed retrospectively. There were five pediatric patients between fetal age and 17 years of age and nine
adults between 31 and 62 years of age. Overall, females outnumbered males in the series, with a male-to-female ratio of 3:4.
However, males predominated in the pediatric age group with a male-to-female ratio of 1.5:1. The clinical presentation of
children was more acute ranging from 3 days to 2 months. In adults, four patients were asymptomatic, and the remaining five
had symptom duration ranging from 2 weeks to a year. The lymphangiomas occurred in the mesentery (n = 4), retroperitoneum (n = 4), omentum (n = 3), pancreas (n = 2), and spleen (n = 1). All the patients underwent total surgical resection with or without organ resection, and there were no recurrences
at a median follow-up of 2 years (range; 3 months–13 years). This series demonstrates that abdominal lymphangiomas have a
male preponderance and present more acutely in pediatric patients, whereas in adults, female patients predominate and the
history is more chronic.
Presented orally at the 19th World Congress of the International Society for Digestive Surgery (Yokohama) December 2004 相似文献
158.
Wright M Baker A;staff of Mountbatten Ward King's College Hospital London UK 《International journal of health care quality assurance incorporating Leadership in health services》2005,18(1):41-61
PURPOSE: To obtain preliminary data on the short- and medium-term effects and personal acceptability of appreciative inquiry (AI) in staff development in health care. DESIGN/METHODOLOGY/APPROACH: AI is a non-problem-solving management approach focusing on developing current successes into the future through reflection at individual and group level. Individual one-hour interviews were undertaken with nursing staff on a national paediatric liver in-patient ward. They were asked to recount stories based on their experiences of successful delivery of health care, with active listening, followed by reflection on the process. A total of 32 staff members took part with only two refusals. Data were written and analysed by an open coding method. Follow up was obtained two years later using a written, open question method. FINDINGS: The process was emotional-but well received. Staff described quality in interpersonal interactions, preventing errors and engaging their personal values in their work. No improvement in recruitment or retention was shown but a high level of sickness absence fell significantly during the period of the project. Two years later, significant positive effects were recalled and attributed to the interviews by many respondents. AI appears a cost-effective way of connecting professionals' motivation toward quality in their work with strategic intentions. RESEARCH LIMITATIONS/IMPLICATIONS: The interviewer was a medical consultant and ward manager, implying either that the interviews could have worked as a form of managerial supervision or improvements could be a Hawthorne effect. Other unknown influences were likely to be occurring on the ward during the study period. PRACTICAL IMPLICATIONS: Short AI interventions on an individual basis can change sickness absence, at least while the interventions are continuing. It is an important tool for staff motivation with the potential for connecting strategic with micro-operational levels. AI is an approach to NHS management with wide application including appraisal, personal development and mentoring. It can be a positive introduction to reflective practice. ORIGINALITY/VALUE: AI is gaining recognition for its value in staff and service development in health care. The paper shows service and personal effects, cost-effectiveness and illustrates how to use AI for these purposes. 相似文献
159.
160.
Davidson AJ London B Block GD Menaker M 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2005,27(2-3):307-311
Acute cardiovascular events exhibit a circadian rhythm in the frequency of occurrence. The mechanisms underlying these phenomena are not yet fully understood, but they may be due to rhythmicity inherent in the cardiovascular system. We have begun to characterize rhythmicity of the clock gene mPer1 in the rat cardiovascular system. Luciferase activity driven by the mPer1 gene promoter is rhythmic in vitro in heart tissue explants and a wide variety of veins and arteries cultured from the transgenic Per1-luc rat. The tissues showed between 3 and 12 circadian cycles of gene expression in vitro before damping. Whereas peak per1-driven bioluminescence consistently occurred during the late night in the heart and all arteries sampled, the phases of the rhythms in veins varied significantly by anatomical location. Varying the time of the culture procedure relative to the donor animal's light:dark cycle revealed that, unlike some other rat tissues such as liver, the phases of in vitro rhythms of arteries, veins, and heart explants were affected by culture time. However, phase relationships among tissues were consistent across culture times; this suggests diversity in circadian regulation among components of the cardiovascular system. 相似文献