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INTRODUCTION: p21WAF1/CIP1 may act as a tumour suppressor gene (TSG) and loss of the p21WAF1/CIP1 gene has been reported in several solid tumours. The aim of this study was to see whether p21WAF1/CIP1 was expressed in metastatic prostate cancer cell lines and to determine if there was methylation of the p21WAF1/CIP1 promoter. METHOD: PC3, LNCaP and DU145 metastatic prostate cancer cell lines, 1542NP normal prostate, and RD rhabdomyosarcoma cell lines were cultured in the demethylating agent 5-Aza-2 deoxycytidine (5-Aza-CdR). p21WAF1/CIP1 mRNA expression was analysed by RT-PCR. DNA from untreated cell lines was modified with sodium bisulphite and promoter sequencing was performed. RESULTS: p21WAF1/CIP1 was expressed at low or undetectable levels in metastatic prostate cancer cell lines but expression was reactivated by treatment with 5-Aza-CdR. Sequence analysis of the promoter region revealed several sites of methylation at the 5' end of a CpG island in the PC3, LNCaP and DU145 cell line DNA but not in the normal prostate control DNA. Most notably the Sis-inducible element (SEI)-1-a STAT1-binding site, was methylated. CONCLUSIONS: In this study, we show that p21WAF1/CIP1 expression in metastatic prostate cancer cell lines is enhanced as a result of demethylation of the DNA. Furthermore, several cytosine residues in the promoter region are methylated, including critical binding sites. The inhibition of the STAT1-signalling pathway by methylation of the promoter may inactivate the p21WAF1/CIP1 TSG in prostate cancer.  相似文献   
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Delirium Tremens     
The varied clinical manifestations and management of 14 male patients with delirium tremens (DT) have been studied. Eight patients were initially hospitalised for diseases unrelated to ethanol abuse i.e. 2 each for gun shot wound, myocardial infarction and stroke, and one each for pneumonia and gastroenteritis. One patient was going through withdrawal because of prodrome of viral hepatitis before he was hospitalised for uncontrolled agitation and delirium. Two known cases of mild essential hypertension on dietary therapy reported for agitation, abnormal behaviour, a single episode of tonic clonic seizure and hypertensive encephalopathy as they could not/did not get alcohol for 3 days. Three patients presented denovo with DT without concomitant illness. The other features besides delirium and hallucinations were tremulousness in 10, tachycardia in 12, fever in 3, diaphoresis in 2 and tonic clonic seizures in 4 patients. The symptoms fluctuated markedly at short intervals and 2 patients did not have any features of sympathetic overactivity. Altered hepatic biochemical parameters and ketonuria with normal blood sugar were noted in 4 and one patients respectively. Other biochemical parameters including serum electrolytes were normal. CT scan brain done for 5 patients revealed subdural haematoma in one. Cerebro spinal fluid (CSF) and EEG findings were noncontributory. All made good recovery with heavy doses of intravenous vitamin B complex, glucose and oral benzodiazepine. Short course of haloperidol was used in 2 patients. Two patients developed pancreatitis during follow up. All patients made complete recovery, and 8 patients have been followed for 8 to 12 months without relapse. The reason for hospitalisation in such cases is often unrelated to alcohol abuse; hence a detailed history of alcoholism is mandatory to identify those at risk as well as for prompt treatment and decreasing the mortality.Key Words: Alcohol withdrawal, Concomitant illnesses, Delirium, Precipitating events  相似文献   
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AIMS: To assess the frequency and cause of incidental (non-metastatic) lymph node pathology discovered before or at radical prostatectomy. METHODS: Eight hundred and fifty four consecutive lymphadenectomies received between 1988 and 2001 were reviewed. All had been processed and stained routinely. Additional techniques, indicated by morphology, were then performed. RESULTS: Incidental pathology was found in 15 cases: florid sinus histiocytosis following prosthetic joint replacement (eight), non-caseating granulomas (three), small lymphocytic cell lymphoma (two), follicular lymphoma (one), and foreign body reaction (one). Incidental pathology was present in 1.8% of 854 patients who underwent pelvic lymphadenectomy during radical prostatectomy. CONCLUSION: Awareness of possible non-metastatic lymph node pathology aids histological diagnosis and may be clinically relevant.  相似文献   
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BACKGROUND: There are few data concerning the risk of contamination of enteral feeding systems via gastrostomy in children, and none for conditions that pertain to home-based care. METHODS: To investigate the risk of contamination of enteral feeding systems during the home-based care of 20 children receiving gastrostomy tube feeding, five samples were taken for analysis: two samples before the enteral feeding period (gastrostomy, enteral feeding system) and three after this period (gastrostomy, distal giving set, liquid remained in container). Microorganisms were identified and counted. Different factors were studied to elucidate their role in bacterial colonization: acid suppressive therapy, gastrostomy tube or button, hanging feeding time, rate of enteral feeding, gastric pullulation and retrograde contamination, manipulation error, and use of open or closed enteral feeding systems. RESULTS: Overgrowth was defined as a microorganismal load exceeding 10(4) colony-forming units (cfu)/mL. Overgrowth was present in 85% of gastrostomy samples before enteral nutrition started. Most microorganisms belonged to gastric flora. Some bacteria had an environmental origin or derived from cutaneous flora. Forty-five percent of the lines showed overgrowth at the end of enteral nutrition period, mainly with the same microorganism found in the gastrostomy. Closed enteral bags remained sterile, even if manipulation error occurred. Duration, rate of enteral feeding, and acid suppression treatment were not risk factors for overgrowth. CONCLUSIONS: Retrograde contamination of gastrostomy feeding systems occurs frequently. The preferential use of closed enteral feeding systems is recommended for home-based enteral nutrition programs.  相似文献   
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