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111.
Genetic and epigenetic changes in nasopharyngeal carcinoma   总被引:15,自引:0,他引:15  
Nasopharyngeal carcinoma (NPC) is a malignancy with remarkable racial and geographic distribution. The development of this EBV-associated cancer likely involves cumulative genetic and epigenetic changes in a background of predisposed genetic and environmental factors. Genome-wide studies have unravelled multiple chromosomal abnormalities with involvement of specific oncogenes and tumour suppressor genes. Alterations of genes such as Ras association domain family 1A (RASSF1A), p16/INK4A, p14/ARF suggest that multiple cellular pathways were dysregulated in the NPC cells. Studies on the precancerous lesions revealed early genetic changes and a critical role of EBV latent infection in the development of this cancer. Based on the existing findings, a pathogenetic model for NPC is proposed.  相似文献   
112.
Systemic lupus erythematosus induced by Epstein-Barr virus infection   总被引:4,自引:0,他引:4  
We report a 22-year-old woman who developed systemic lupus erythematosus (SLE) immediately after an Epstein-Barr virus (EBV)-induced mononucleosis infection. The link between these two conditions has long been suspected. The close temporal relationship, the course of the pathological events and the development of immunological changes in this case provide further evidence supporting the hypothesis that EBV infection could work as a trigger in some cases of SLE, particularly if the patient is genetically susceptible.  相似文献   
113.
Association with Epstein-Barr virus (EBV) infection has been noted in various types of cutaneous lymphoproliferative disorders. We report a 57-year-old Japanese woman with T-cell lymphoma mimicking dermatomyositis that was associated with chronic active EBV infection. She presented with low-grade fever, bilateral erythematous swellings on the eyelids, and necrotic papules on the face. Serum creatine kinase levels were elevated and a diffuse reticular shadow was detected in both lung fields. The infiltrate of atypical lymphocytes found in skin and muscle, which contained EBV-encoded small nuclear RNA-1 and EBV, was also detected in the CD4+ peripheral blood cells. Treatment with prednisolone resolved her lesions with no relapse for 3 years, after which there was a recurrence in her left lung. Combination chemotherapy was not effective against the lung lesion and she died with multiple organ failure 2 months after the recurrence.  相似文献   
114.
①目的建立EB病毒感染的人胃上皮细胞细胞株,并进行鉴定。②方法将舍有NEOr基因的重组EBV感染人胃上皮细胞GES-1.同时以pcDNA3(NEOr)空载体质粒经脂质体法持染同一细胞为对照,用有限稀释法进行克隆,经G418筛选,用免疫荧光组织化学法鉴定EBV编码的核抗原1(EBNA1)的表达情况,直至获得100%表达EBV的单克隆细胞株。③结果感染EBV的GES-1细胞大部分为EBNA1阳性,而转染pcDNA3(NEOr)空载体质粒的GES-1细胞均为EBV阴性。(蓟结论成功地建立EB病毒感染的人胃上皮细胞GES-1细胞株,对EB病毒致胃癌机制的研究具有重要的意义。  相似文献   
115.
This study is to determine the impact of virus in surgical outcomes among patients of head and neck cancer with N3 lymph node metastasis. A retrospective analysis was conducted for 32 patients with operable N3 neck metastasis undergoing surgical treatment between January 1987 and October 2006. The nuclei of the tumor cells were investigated for the presence of human papillomavirus (HPV) and Epstein–Barr virus (EBV) DNAs and were taken into account as the variable for survival analysis. The primary sites were oropharynx in 11 patients, tongue in 3, buccal mucosa in 1, hypopharynx in 8 and unknown primary in 9. The five-year cumulative overall survival rate was 40.7% and 5-year cumulative regional control rate was 55.8%. The 5-year cumulative overall survival rate of patients with unknown primary site (72.9%) and HPV or EBV positive in the tumor (77.8%) were significantly higher than those patients with known primary site (31.3%) and HPV or EBV negative in the tumor (27.4%), respectively (= 0.0335 and = 0.0348, log rank test). In conclusion, surgery with adjuvant therapy offers reasonable outcomes for operable N3 node in head and neck cancer in our cohort. In addition, patients with HPV or EBV positive in the tumor have a better survival.  相似文献   
116.
应用PCR技术和免疫组化SP法检测了46例鼻咽癌组织中EB病毒DNA、EB病毒潜在膜蛋白(LMP-1)的表达。结果发现EB病毒DNA检出率和LMP-1的表达率分别为80.4%和53.3%,EB病毒DNA检出率和LMP-1表达与鼻咽癌组织学分级有关。提示EB病毒NDA的存在和LMP-1表达与细胞癌变关系密切  相似文献   
117.
A UK population-based case-control study of Hodgkin's disease (HD) in young adults (16-24 years) included 118 cases and 237 controls matched on year of birth, gender and county of residence. The majority (103) of the cases were classified by Epstein-Barr virus (EBV) status (EBV present in Reed-Stenberg cells), with 19 being EBV-positive. Analyses using conditional logistic regression are presented of subject reports of prior infectious disease (infectious mononucleosis (IM), chicken pox, measles, mumps, pertussis and rubella). In these analyses HD cases are compared with matched controls, EBV-positive cases and EBV-negative cases are compared separately with their controls and formal tests of differences of association by EBV status are applied. A prior history of IM was positively associated with HD (odds ratio (OR) = 2.43, 95% confidence interval (CI) = 1.10-5.33) and with EBV-positive HD (OR = 9.16, 95% CI = 1.07-78.31) and the difference between EBV-positive and EBV-negative HD was statistically significant (P = 0.013). The remaining infectious illnesses (combined) were negatively associated with HD, EBV-positive HD and EBV-negative HD (in the total series, for > or =2 episodes compared with < or =1, OR = 0.45, 95% CI = 0.25-0.83). These results support previous evidence that early exposure to infection protects against HD and that IM increases subsequent risk; the comparisons of EBV-positive and EBV-negative HD are new and generate hypotheses for further study.  相似文献   
118.
We report a case of primary splenic B-cell CD30 positive large cell anaplastic lymphoma developing in an HIV positive patient. The tumour cells expressed Epstein–Barr virus-associated antigens.  相似文献   
119.
Based on the Barr body frequency, a total of 285 unselected breast cancer tissues were categorised as negative and positive tumours; incidence of these two groups in our series was 2:1, respectively. When 2-years' disease-free interval and 10-years' survival were considered, it was seen that patients harbouring negative tumours had significantly early recurrence and shorter duration of survival as compared to those having positive tumours. As vascular spread is the prerequisite of early recurrence, the shorter survival in the patients having negative tumours could be explained on the basis of blood vessel invasion, in that 73% of the negative tumours had blood vessel invasion, in contrast to only 24% in the positive tumours.  相似文献   
120.
A 23-month-old boy with Wiskott-Aldrich syndrome (WAS) received human leukocyte antigen (HLA)-one locus mismatched, unmanipulated allogeneic bone marrow graft from his mother. An Epstein-Barr virus (EBV)-associated post-transplantation lymphoproliferative disorder (PTLD) of donor cell origin and hemophagocytosis syndrome with fever, lymphadenopathy, hepatosplenomegaly, seizures, involuntary movements and pancytopenia developed 52 days after transplantation. It was difficult to decide on the treatment strategy because the patient presented with B-cell hyperplasia that morphologically appeared malignant but was oligoclonal by heavy-chain analyses. Despite of donor leukocyte transfusion, low dose chemotherapy, and anti-B cell monoclonal antibody immunotherapy, the patient died 107 days after transplantation.  相似文献   
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