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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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Ciprofloxacin was evaluated in chlamydial infections of the urogenital tracts of women treated with a dosage regimen of 500 mg orally twice a day for seven days. Of the 40 women evaluated, 30 were infected with Chlamydia trachomatis only, two were infected with Neisseria gonorrhoeae only, and a further eight had combined gonococcal and chlamydial infections. Ten were found to be harbouring Chlamydia trachomatis in the urethra as well as the cervix. Neisseria gonorrhoeae was eradicated from all patients with or without concomitant chlamydial infection. The overall chlamydial reisolation rates were 14% (5/35) four weeks after treatment and 23% (6/26) 11 weeks after treatment. The organism was not reisolated from the urethra of any of the patients after treatment. Ciprofloxacin was effective against Mycoplasma hominis, but almost completely ineffective against Ureaplasma urealyticum.  相似文献   
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A clinicopalhological study of 70 cases of pemphigus observed over a span of four and a half years from January 1992 to June 1996 at the Sir J.J. Group of Hospitals and Grant Medical College, Mumbai is reported. Pemphigus vulgaris constituted the single largest group of 43 cases, followed by pemphigus foliaceus (25 cases) and pemphigus vegetans (2 cases). Majority of the cases were seen in the age group of 21-60 years, with a slight male predominance. The youngest patient was 14 years while the eldest was aged 75 years. Mucosal involvement was seen in 31 cases of pemphigus vulgaris, as opposed to only 5 cases of pemphigus foliaceus. Flaccid bullae were present in 100% cases. Pruritus was complained of in 14 cases, though it was more common in pemphigus vegetans and vulgaris. Salient histopathological features of pemphigus vulgaris observed were (I) intraepidermal suprabasal blisters (35 cases), (2) presence of acantholytic cells (40 cases), (3) "Row of tombstone appearance" (I8 cases) and (4) acantholysis involving follicular sheath (20 cases). Main histopathological features of pemphigus foliaceus were (1) subcorneal blister (15 case), (2) acantholysis (24 cases) and (3) bulla cavity containing inflammatory infiltrate (12 cases). Both cases of pemphigus vegetans showed hyperkeratosis, papillomatosis and irregular acanthosis with intra-epidermal eosinophilic abscesses besides suprabasal lacunae.  相似文献   
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Metabolic Brain Disease - Mild cognitive impairment (MCI) is transition phase between cognitive decline and dementia. The current study aims to investigate altered metabolic pattern in plasma of...  相似文献   
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Hepatitis E virus (HEV) is an important cause of repeated waterborne outbreaks of acute hepatitis. Recently, several extrahepatic manifestations (EHMs) have been described in patients with HEV infection. Of these, neurological disorders are the most common EHM associated with HEV. The involvement of both the peripheral nervous system and central nervous system can occur together or in isolation. Patients can present with normal liver function tests, which can often be misleading for physicians. There is a paucity of data on HEV-related neurological manifestations; and these data are mostly described as case reports and case series. In this review, we analyzed data of 163 reported cases of HEV-related neurological disorders. The mechanisms of pathogenesis, clinico-demographic profile, and outcomes of the HEV-related neurological disorders are described in this article. Nerve root and plexus disorder were found to be the most commonly reported disease, followed by meningoencephalitis.  相似文献   
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New West African human immunodeficiency viruses (HIV-2s) and simian immunodeficiency virus (SIV) contain functional transactivator (tat) gene and tat response elements. Their long terminal repeats (LTR) and tat genes are more related among themselves than to HIV-1 LTR and tat gene. The viral gene expression of HIV-2 as well as SIV can be stimulated by T cell activators, such as mitogens and phorbol esters. HIV-2 and SIV display a much broader transactivation response specificity than does HIV-1. The LTR-directed gene expression of HIV-2/SIV is not only transactivated by their own tat gene and by HIV-1 tat gene but also by factors in human T cell leukemia/lymphoma virus type I (HTLV-I) and simian virus 40 (SV40) infected cells, involving HTLV-I tat gene and SV40 T antigens, respectively. HIV-1 LTR-directed gene expression is much less transactivated by HIV-2/SIV tat genes and by factors in HTLV-I- and SV40-infected cells. Immune activation and heterologous transactivation of the LTR-directed gene expression may be relevant to the latency of virus infection and progression toward the acquired immunodeficiency syndrome (AIDS).  相似文献   
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