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1.
2.
Although infectious mononucleosis due to Epstein-Barr virus (EBV) is a common disease among young individuals, central nervous system (CNS) complications are rare. In this report, we describe a case of CNS complications caused by EBV in a previously healthy young woman. She presented to our hospital with a 9-day history of headache and sore throat, followed by the development of fever and facial edema 6 days prior to admission. On Day 2 of admission, she was confused (Glasgow Coma Scale score: 10 points) and had fever, muscle weakness in her right arm and leg, stiff neck, and roving eye movement. We detected EBV in a cerebrospinal fluid (CSF) sample using a polymerase chain reaction (PCR) test. The magnetic resonance imaging of her brain revealed dural enhancement and right parietal and temporal lobe lesions. She was treated with acyclovir and high-dose steroid therapy. She responded well to treatment, recovered without neurologic sequelae, and was discharged home on Day 12.Our experience suggests that PCR detection of EBV DNA in CSF may be useful in diagnosing EBV encephalitis and that prognosis may be associated with an area of the brain that is affected and the time from symptom onset to starting treatment.  相似文献   
3.
目的:探讨EB病毒(EBV)感染与非鼻咽部T细胞淋巴瘤的关系。方法:用单克隆抗体UCHL-1、L26及EB病毒编码的潜在膜蛋白-1(LMP-1),免疫组化染色确定肿瘤的免疫表型及EB病毒转化蛋白的表达。采用原位杂交方法检测EBV编码的EBERs。结果:21例非鼻咽部T细胞淋巴瘤EBERs5例阳性的(23.8%),其中给内淋巴瘤3例,肺和胃肠淋巴瘤各1例。阳性细胞约占肿瘤细胞的10%~70%。5例EBERs阳性病例中仅1例表达LMP-1,为结内淋巴瘤。结论:非鼻咽部T细胞淋巴瘤可能与EBV的感染有关,LMP-1的阳性率较EBERs低。  相似文献   
4.
传染性单核细胞增多症为EB(Epstein-Barr)病毒引起的一种急性或亚急性全身性免疫异常疾病。一次患病后,可获得持久免疫力,多次发病罕见。本文报告了一例传染性单核细胞增多症,9年内3次发病,结合文献资料复习,就本病的诊断、治疗、临床分型、复发问题以及与肿瘤的关系进行了讨论。  相似文献   
5.
An enzyme-linked immunosorbent assay (ELISA) was used to measured IgG antiboody titers againt a synthetic peptide whose sequence was derived from the glycine-alanine repeating region of Epstein-Barr virus nuclear associated antigen 1 (EBNA-1). Antibody titers were determined in sera from 15 normal subjects, sera from 21 normal male siblings of X-linked lymphoproliferative syndrome (XLP) patients, from 20 XLP patients comprising a total of 42 samples, and ten samples before and ten samples after gamma-globulin therapy in ten patients with XLP. Data analysis demonstrated that while there are differences between the ELISA and ACIF, they appear to measure a similar response as demonstrated by their correlation coefficient (0.77) and the GMT to EBNA observed by both methods. No cross-reactivity of cytomegalovirus antibodies to the EBNA-1 peptide was observed by immunobv using adsorption against AD-169 infected MRC-5 cells.. However, non-specific binding was observed if samples were not pre-incubated in a 10% goat serum PBS-Tween 20 solution. This pre-treatment removed the non-specific binding that falsely elevated GMT in approximately 15% of both normal and XLP samples in ELISA. The ELISA system appears to be a sensitive, reproducible and objective test that may be useful for assessing the antibody responses of patients to the EBNA-1 protein.  相似文献   
6.
We studied 44 cases of Hodgkin's disease for the presence of Epstein-Barr virus (EBV) DNA, its localization and the expression of the EBV receptor on the tumour cells. EBV DNA was found in 52% (16/31) of the Hodgkin's lymphomas using the polymerase chain reaction. With a very sensitive non-radioactive DNA in situ hybridization technique in combination with immunohistochemistry for CD 30 or CD 15 antigens, EBV DNA was localized to Reed-Sternberg cells and its mononuclear variants. The relationship between the presence of EBV DNA and the expression of the EBV-receptor CR2 (CD 21) on Reed-Sternberg cells was studied using the same techniques and two different monoclonal anti-CD 21 antibodies. CR2 could be detected on a substantial number of the Reed-Sternberg cells in EBV DNA positive Hodgkin's lymphomas (9/12; 75%), whereas in EBV negative cases positivity with anti-CD 21 was rare (1/13; 8%). The results indicate that CR2 expression on Reed-Sternberg cells and the presence of EBV DNA sequences are frequently associated in Hodgkin's lymphomas.  相似文献   
7.
Epstein-Barr virus (EBV) was inoculated into two species of marmosets. Successful infection was established in the majority of the animals of one species, Callithrix jacchus, as evidenced by the development of high, persistent levels of antibody against virus-specific capsid and early nonstructural proteins. Antibodies also were produced against the major membrane antigen and, in some animals, against EBV nuclear antigen (EBNA) 2 but not against EBNA 1. This is the antibody profile normally noted in individuals with chronic infectious mononucleosis (IM). EBV-induced lymphoproliferation was not seen, and EBV-specific proteins were not detected in the peripheral blood lymphocytes of infected animals. Hence, EBV infection in C. jacchus apparently does not generally include extensive B-cell involvement. However, the marmosets clearly are useful as a model for EBV primary infection and also possibly for chronic IM.  相似文献   
8.
In activated murine B lymphocytes, immunoglobulin class switch recombination occurs as a highly regulated process which is targeted to distinct switch regions. Here we present first evidence that in human B lymphocytes, switch recombination is targeted to distinct switch regions as well. In a panel of clonally unrelated IgG1-expressing human B cells, immortalized by Epstein-Barr virus (EBV) transformation, seven out of nine cells show switch recombination between Sμ and Sγ1 on both alleles, the active and inactive one. The remaining cells show no switch recombination on the inactive IgH locus. The very strong correlation of switch recombination on both alleles of IgG1-expressing cells proves that class switch recombination to IgG1 is not random but directed in human B lymphocytes.  相似文献   
9.
Oral hairy leukoplakia is an epithelial lesion of the tongue associated with productive infection by Epstein-Barr virus (EBV). However, no data concerning the pattern of EBV latent gene expression have been reported, and it remains unresolved whether true latent infection occurs in basal cell layers of oral hairy leukoplakia. We have studied six cases of oral hairy leukoplakia using monoclonal antibody immunohistology for EBV latent--EB nuclear antigen (EBNA) 1, EBNA 2 and latent membrane protein 1 (LMP 1); immediate-early (BZLF1); and replicative (EA, VCA, MA) proteins, and for the EBV-receptor (CD21 antigen). EBV DNA was demonstrated by nucleic acid in situ hybridization. Mid- to upper-zone keratinocytes contained EBV DNA and co-expressed EBNA 1, EBNA 2 (5 of 6 cases), LMP 1, BZLF1 protein, EA, VCA and MA. No EBV genome or gene expression could be demonstrated in basal or parabasal cells. Spinous keratinocytes were labelled by anti-CD21 antibodies HB5 and B2, but did not express the EBV-receptor as defined by reactivity with OKB7. The co-expression of latent and replicative infection-associated antigens is striking, indicating possible functional roles for latent proteins during the productive cycle. Our results suggest that oral hairy leukoplakia is caused by repeated direct infection of upper epithelial cells with virus from saliva or adjacent replicatively infected cells, rather than by a latent EBV infection of basal epithelial cells with a differentiation-dependent switch to productive infection as previously proposed.  相似文献   
10.
Two recently discovered genes, the recombination activating genes 1 and 2 (RAG-1 and RAG-2), are necessary to perform variable (V), diversity (D), and joining (J) recombination. They synergistically activate VDJ recombination to generate immunocompetent lymphocytes. Disruption of either gene results in a maturation arrest at a very early B and T cell progenitor stage. Expression and downregulation of RAG's are closely associated with interleukin 7, sIgM and TCR-CD3 complex, respectively. Assessment of RAG mRNA expression is a valuable marker in identifying the genotypic maturation status of leukemias and lymphomas. Persistent RAG expression in otherwise mature lymphoid proliferations may explain puzzling biological and clinical observations such as multiple rearrangements in lymphomas with a mature phenotype. Lack of RAG expression in Hodgkin's disease with abundant Reed-Stern-berg cells is consistent with a mature phenotype of the latter. Availability of a anti-RAG-1 monoclonal antibody in the near future will facilitate RAG analysis of lymphomas.  相似文献   
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