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21.
The study was undertaken to detect the risk of infection, if any, among 193 household contacts of 40 hospitalised hepatitis patients (group I) with hepatitis B surface antigen (HBsAg) in their blood. As a control group, 103 household contacts of 27 hospitalised hepatitis patients who were negative for HBsAg (group II) were investigated. The family contacts of the former group had a significantly higher prevalence of HBV infection than those of the latter group (P less than .001). Significant differences were observed both in the prevalence of HBsAg (P less than .05) and antibody to HBsAg (anti-HBs) (P less than .025) between the two groups. IgM antibody to hepatitis B core antigen (anti-Hbc-IgM) was detected in 32 out of the 39 (82%) sera tested from the patients of group I with HBsAg. A statistically significant difference (P less than .005) of HBV prevalence was also found in the contacts of these 32 patients suffering from acute hepatitis B as compared to the contacts of the patients of group II. Overall, the children of the first group showed a significantly higher prevalence of HBsAg as compared to the second group. All the children with HBsAg were positive for HBeAg also, but were negative for anti-HBc-IgM. Anti-HBs was detected in a significantly larger number of adult females. Spouses were found to be affected more than other relatives. A significant difference (P less than .025) was noted in the number of families having HBV markers in group I (80.0%) as compared to those in group II (48.1%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
22.
The analysis of 23 clinical isolates of herpes simplex virus type 1 (HSV-1) showed that 15 of 15 isolates that had undergone a few passages in tissue culture (fresh isolates) and two of eight isolates that had never been passaged (new isolates) were composed of a mixed population with respect to plaque morphology in Vero cells. Cloning and characterization of 10 large plaque viruses (L variants) and nine small plaque viruses (S variants), obtained from seven different isolates, showed the following. BamHI DNA restriction patterns of the L and the S variants from a single isolate differed only with respect to the electrophoretic mobility of the fragments that contain reiteration of specific sequences; they did not differ regarding the presence or the absence of restriction endonuclease cleavage sites. The L and S variants differed with respect to the electrophoretic profiles of infected cell glycoproteins, thermosensitivity of growth and plaquing efficiency at 39 degrees C, and, at least in the case of the two couples of variants that we tested, pathogenicity for the mouse. The hypothesis that the L variants might arise from the S variant during in vivo replication is discussed.  相似文献   
23.
A rapid simultaneous enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies was investigated for herpes simplex virus (HSV) detection. All HSV isolated (n = 127) were detected, whereas no response was obtained with HSV negative preparations. Equivalent results were obtained from 275 of 277 clinical specimens in the monoclonal ELISA and in an ELISA using polyclonal antibodies, confirming that appropriately selected monoclonal antibodies may be as efficacious as polyclonal antibodies in antibody-based assays. In clinical specimens, the rate of HSV detection (sensitivity) relative to tissue culture isolation was low for both assays, and the major factor responsible for this was the low concentration of virus present in some specimens. The sensitivity of ELISA obtained in routine use varied with different panels of unselected specimens and was related to the speed of development of the cytopathic effect. These results emphasise the need for caution in assigning a definitive sensitivity level to ELISA tests evaluated on different panels of specimens.  相似文献   
24.
 Patients suffering from the acquired immune deficiency syndrome (AIDS) have a 20000-fold increased risk of developing a severe form of Kaposi’s sarcoma (KS), a previously rare malignancy involving sharply defined nodular lesions of the skin and/or oral mucosa. Epidemiological evidence has long suggested that an infectious agent is the probable cause of KS. Recently sequences from a putative new herpesvirus have been found to be associated with KS in virtually 100% of the cases analyzed. The suspected etiological agent, a new human herpesvirus termed Kaposi’s sarcoma associated herpes virus (human herpes virus 8) has now been propagated in cell culture. This significant advance should form the basis for a detailed analysis of the pathogenetic mechanisms involved in the development of KS. Received: 4 June 1996 / Accepted: 5 August 1996  相似文献   
25.
Objective  To investigate the appearance of cytomegalovirus (CMV) DNA, human herpesvirus-6 (HHV-6) DNA and human herpesvirus-7 (HHV-7) DNA in plasma as a sign of reactivation and possible causes of fever of unknown origin (FUO) during neutropenia.
Methods  From 134 patients with febrile neutropenia following cytotoxic chemotherapy during the years 1996–2000, 20 severely neutropenic patients (granulocyte count < 0.1 × 109/L) were selected. Ten were patients with bacteremia and ten were patients with FUO. Five samples from each patient were selected at the start of chemotherapy, at the time of blood culture and fever, after 24 and 48 hours of fever, and, finally, after two to three days without fever. Virus DNA was detected by real-time quantitative and nested polymerase chain reaction (PCR).
Results  CMV-DNA was detected in two out of ten FUO-patients in all samples drawn during fever. From another FUO and during two bacteremia episodes, CMV-DNA was detected after 48 hours of fever. DNA from HHV-6 and HHV-7 was not detected in any of the 20 febrile episodes.
Conclusions  HHV-6 and HHV-7 as a possible explanation for FUO in severely neutropenic patients treated with cytotoxic chemotherapy seems not be very likely. However, CMV was identified in 5/20 patients and the febrile episodes in the two FUO-patients with constant DNA-emia may have been caused by a reactivation of CMV. This implies that CMV infection can be expected not only in transplant patients but also in chemotherapy-treated neutropenic patients.  相似文献   
26.
The HLA DQA1 locus is polymorphic. Haplotypes containing HLA DQA1*0501, but not HLA DQA1*0201, together with HLA DQB1*0201 are associated with Grave's disease and celiac sprue. In this report, we demonstrate a functional correlate of DQA1 polymorphism. T cells infiltrating a herpes simplex virus (HSV) lesion from a HLA DQ 2,7 individual yielded a virusspecific CD4+ clone restricted by DQ2. Presentation of viral peptide and protein segregated with DQA1 allele, because cell lines bearing DQA1*0501/DQB1*0201 heterodimers presented antigen in proliferation and cytotoxicity assays much more efficiently than cell lines bearing DQA1*0201/DQB1*0201. Binding of viral peptide to cell lines bearing DQA1*0201, in comparison to DQA1*0501, was only moderately reduced and may not explain this effect. Truncation and substitution analyses of peptide binding and T-cell activation were performed to determine which viral peptide residues contacting TCR might therefore be presented in an altered conformation by DQA1*0201/DQB1*0201. Residues 432, 435, 437, 438, and 440 (position P1, P4, P6, P7, and P9) contributed to DQ2 binding, whereas residues 431, 433, 434, and 436 (positions P-1, P2, P3, and P5) contributed to TCR contact. Differential presentation of peptide by HLA DQ2 heterodimers varying at the DQA1 locus may have relevance to host defense and the pathogenesis of HLA DQ2-associated autoimmune diseases. Human Immunology 53, 195-205 (1997).  相似文献   
27.
单克隆抗体间接荧光法分型检测单纯疱疹病毒的实验研究   总被引:2,自引:0,他引:2  
本文选择3株抗单纯疱疹病毒型共同性和型特异性单克隆抗体,建立了分型检测单纯疱疹病毒的单克隆抗体间接荧光法(McAb-1FA).特异性试验和重复性试验证实,McAb-IFA特异性强、重复性好.用此法检测了不同部位来源的51份临床分离株,分型检测结果与ELISA法检测结果一致.提示McAb-IFA有可能成为实验室分型检测单纯疱疹病毒可靠的方法.  相似文献   
28.
Infections of the central nervous system (CNS) caused by herpes viruses can result in severe diseases, often with a fatal outcome. In this study, the viral load in the cerebrospinal fluid (CSF) of patients with herpes simplex or varicella-zoster infections of the CNS was measured using a quantitative real-time PCR. The results suggest a high variability in viral load, with relatively mild disease associated with a high viral load in CSF and vice versa. Determination of the viral load in CSF does not therefore seem to be useful in assessing the prognosis of disease caused by these viruses.  相似文献   
29.
The UL41 gene of the HSZP strain of herpes simplex virus type 1 (HSV-1) defective with respect to the early shutoff of host protein synthesis was sequenced and compared with the corresponding HSV-1 strain KOS and 17 gene sequences. In comparison with strain 17, nine mutations (base changes) were HSZP specific, five KOS specific and four were common for both strains. Nine mutations caused codon changes. Three of these mapped to the nonconserved regions and the others to the conserved regions of the functional map of UL4l gene. One KOS specific mutation mapped to the region responsible for the binding of the virion host shutoff (vhs) protein to the alpha-transinducing factor (VP16). The possible relationship between mutations and host shutoff function is discussed. The nucleotide sequence data of the UL41 gene of HSZP and KOS have been submitted to the Genbank nucleotide database and have been assigned the accesion numbers Z72337 and Z72338. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
30.
The current study examined how individuals deal with genital herpes, a recurrent, incurable disease with a great psychological impact. An assessment battery composed of cognitive and problem-focused coping, attribution, and social support mechanisms was employed. These coping mechanisms were correlated with measures of psychological adjustment: self-esteem, depression, sexual adjustment, and amount upset by herpes. Subjects were 152 people with herpes recruited from self-help groups and people from the community who volunteered to participate in the study. Results supported several hypotheses derived from previous research on coping with life stressors. Cognitive coping mechanisms, especially negative thoughts, along with wishful thinking and characterological self-blame, were significant predictors of poor psychological adjustment. Social support was correlated with better psychological adjustment. In addition, the repeated use of disease management strategies was found to correlate with poor psychological adjustment. Further research in the area of coping with chronic illness is suggested.  相似文献   
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