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41.
Clinical recurrences of Herpes simplex virus type 1 (HSV-1)-associated genital herpes are thought to be caused by reactivation of latent endogenous HSV-1. However, the possibility of reinfection with exogenous HSV-1 cannot be excluded. This study aimed to determine the incidence of genital HSV-1 superinfection in patients by investigating the genotype of sequential HSV-1 isolates obtained from the same anatomical site of patients with clinical recurrences of genital HSV-1 recurrent genital herpes. Sequential genital HSV-1 isolates were genotyped by PCR amplification of the hypervariable regions located within the HSV-1 genes US1 and US12. Whereas the sequential HSV-1 isolates in 11 of the 13 patients studied had the same genotypes, the sequential isolates of 2 patients showed a different genotype. The data suggest that HSV-1-induced recurrent genital herpes can be associated with genital reinfection with an exogenous HSV-1 strain.  相似文献   
42.
Fluorescence in situ hybridization (FISH) with microdissection probes from human chromosomes 3 and 6 was applied to visualize arm and subregional band domains in human amniotic fluid cell nuclei. Confocal laser scanning microscopy and quantitative three-dimensional image analysis showed a pronounced variability of p- and q-arm domain arrangements and shapes. Apparent intermingling of neighbouring arm domains was limited to the domain surface. Three-dimensional distance measurements with pter and qter probes supported a high variability of chromosome territory folding.  相似文献   
43.
Monosomy for the short arm of chromosome 18 is one of the most frequent autosomal deletions observed. While most cases result from terminal deletion of 18p, 16% of cases reported were as a result of an unbalanced whole arm translocation resulting in monosomy 18p. The origin and structure of these derivative chromosomes were reported in only a few cases. We report the prenatal diagnosis and characterization of a new case of monosomy 18p as a result of an unbalanced whole arm translocation. Amniocentesis was performed at 15 weeks of gestation on a 34-year-old woman initially referred for advanced maternal age. Holoprosencephaly was identified by ultrasound at the time of amniocentesis. Karyotype analysis showed an unbalanced whole arm translocation between the long arm of one chromosome 18 and the long arm of one chromosome 22, 45,XX,der(18;22)(q10;q10), in all metaphases. In effect, the fetus had monosomy for 18p. Parental karyotypes were normal, suggesting a de novo origin for the der(18;22). Fluorescence in situ hybridization (FISH) analysis was performed with alpha-satellite probes D18Z1 and D14Z1/D22Z1 to identify the origin of the centromere on the der(18;22). Signal was observed with both probes, indicating that the centromere was composed of alpha-satellite DNA from both constituent chromosomes. Genotyping of the fetus and her parents with chromosome 18p STS marker D18S391 showed only the paternal 187 bp allele was present in the fetus, indicating that it was the maternal chromosome 18 involved in the der(18;22). This case and previous reports show that de novo unbalanced whole arm translocations are more likely to retain alpha-satellite sequences from the two chromosomes involved.  相似文献   
44.
The large-scale structure of chromatin corresponding to G- and R-bands in human G0/G1 interphase nuclei was compared. Fluorescence in situ hybridization (FISH) was used to measure the interphase distance between 42 pairs of probes separated by 0.1–1.5Mbp. The probe pairs were derived from 21q22.2 and Xp21.3, G-band positive regions, and from 4p16.3, 6p21.3, and Xq28, R-band positive regions. Distributions of measured interphase distances in all regions approximated a Rayleigh distribution, suggesting that the chromatin follows a random-walk path over this range. A linear correlation of mean-square interphase distance and genomic separation, also indicative of random-walk folding, was observed in all regions. The slope of the correlation observed using probes from G-band regions was systematically lower than that from R-band regions. The difference in the slope between Xp21.3 and Xq28 was particularly striking and was observed in normal fibroblast cells, fixed alternatively with methanol and acetic acid or paraformaldehyde, and HeLa cells. These results demonstrate regional differences in large-scale chromosome structure during interphase, with the more openly configured chromatin corresponding to R-bands.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   
45.
Antibody penetration of viable cells and interaction with intracellular antigens may have major consequences for immunopathological processes in connective tissue diseases. We have reported previously that antibody can penetrate viable human lymphocytes. To assess further the role of antinuclear antibodies in this process, peripheral blood lymphocytes (PBMC) were incubated with FITC-conjugated IgG fractions from sera containing anti-RNP (anti-RNP IgG), Ro(SS-A), La(SS-B) and dsDNA antibodies and control sera for 24 h. Using crystal violet to quench cell surface staining, intracellular fluorescence of viable lymphocytes was quantified on the flow cytometer. It was noted that anti-RNP IgG entered 46.4 +/- 7.2% of lymphocytes which was significantly higher than anti-Ro(SS-A) (29.9 +/- 4.1%, P less than 0.05), La(SS-B) (22.0 +/- 7.5%, P less than 0.01) IgG and control IgG (28.8 +/- 2.1%, P less than 0.05) and not statistically different from anti-dsDNA IgG (32.6 +/- 14.3%). Inhibition experiments showed that the increased number of cells penetrated by anti-RNP IgG was a specific process. Time-course studies showed that anti-RNP IgG entry into cells was different from pooled control IgG. With anti-RNP IgG, positive-staining lymphocytes gradually increased in number from 12 to 24 h incubation, whilst with pooled control IgG, the peak was reached within 5 min. Dual staining experiments suggested that whereas both anti-RNP IgG and pooled control IgG entered B and NK cells, anti-RNP IgG also entered T cells. Using IgG F(ab')2 and Fc fragments from either anti-RNP IgG or pooled control IgG to compete with their FITC-conjugated counterparts indicated that the entry of anti-RNP IgG into-viable cells appeared to involve both F(ab')2 and Fc fragments, and pooled control IgG depended exclusively on the Fc portion of IgG. Further investigation by incubating anti-RNP IgG with 35S-methionine-labelled monocyte-depleted PBMC (MD-PBMC) suggested that anti-RNP IgG might react with the corresponding antigens either on the cell surface or within the cytoplasm.  相似文献   
46.
目的:探讨脂血、高胆红素和溶血标本对乙肝病毒DNA(HBVDNA)荧光定量测定结果的影响。方法:将乙肝大三阳高脂血和非脂血、溶血血清和未溶血血清同时作HBVDNA荧光定量检测;将HBVDNA阴性黄疸血清和HBVDNA阴性正常血清与来自同一份乙肝大三阳血清混合,在相同条件下进行HBVDNA荧光定量。结果:乙肝大三阳溶血与未溶血样本HBVDNA含量都在同一数量级。乙肝大三阳高脂血的HBVDNA含量明显低于对照标本。高黄疸血清、正常对照血清与相同的HBVDNA阳性模板组合后所测得的HBVDNA结果无差异。结论:脂血对HBVD-NA定量测定有严重干扰;溶血样本、高胆红素样本对HBVDNA测定结果无影响。  相似文献   
47.
采用聚合酶链反应(PCR)技术,对42例肝活切组织石蜡切片中乙型肝炎病毒(HBV)DNA进行检测,并与乙肝表面抗原(HBsAg)的免疫组织化学及血清学检测进行比较,HBV-PCR阳性率为73.8%,高于组织及血清HBsAg阳性率(分别为59.5%和50.0%)。3例病理形态呈肝炎改变,而血清HBsAg(─)的肝组织中有2例检出HBV-DNA,提示PCR的高度敏感性和准确性。83.3%的门脉性肝硬变和87.5%的肝细胞癌组织中HBV-PCR呈阳性,进一步证实了上述两病与HBV的关系密切。我们还发现肝细胞淤胆患者HBV感染率较高,HBV-DNA及组织HBsAg阳性比例各为6/9和4/8。  相似文献   
48.
49.
The prevalence of hepatitis C antibodies (anti- HCV) among multitransfused patients was studied and compared with predicted values obtained from a post-transfusion hepatitis study and from data on the prevalence of anti-HCV among blood donors. The prevalence of hepatitis B core antibodies (anti-HBc) was also studied to determine the routes of transmission of hepatitis C virus. The patients consisted of 65 dialysis patients (57 on haemodialysis and 8 on continuous ambulatory peritoneal dialysis) and 71 leukemia patients in long-term remission [49 with acute myeloid leukemia (AML) and 22 with acute lymphatic leukemia (ALL)]. The presence of anti-HCV was investigated using a second generation enzyme-linked immunosorbent assay. Reactive samples were confirmed by a second generation recombinant immunoblot assay. Anti-HBc was studied in the 65 dialysis patients and in 40 of the leukemia patients. Three (4.6%) of the 65 dialysis patients and 12 (24.5%) of the 49 AML patients were anti-HCV positive whereas all of the ALL patients were seronegative. The total number of blood units transfused to 134 patients (data on two dialysis patients were not available) was 18,148, out of which 17,575 units had been transfused prior to the initiation of anti- HCV screening of blood donors. On the basis of the anti-HCV prevalence among blood donors and the incidence of post-transfusion hepatitis, the predicted number of seropositive patients was 11 and 18, respectively. Five of the 65 dialysis patients were anti-HBc positive, compared with only one of the 40 leukemia patients. It is concluded that the anti-HCV prevalence among dialysis and leukemia patients is concordant with the risk of receiving contaminated blood products, whereas hepatitis B infection may have other routes of transmission in dialysis patients. © 1993 Wiley-Liss, Inc.  相似文献   
50.
The MOG locus, located on chromosomal bands 6p21.3-p22 and mapped about 100 kb telomeric to HLA-F, was isolated from cosmid ICRFcl09A2434 and shown to contain three microsatellites. These CA-repeat polymorphic markers were characterized in a sample of 173 healthy unrelated individuals and 84 DNAs from the HLA Workshop reference panel, by a method combining fluorescence labeling of PCR products and use of an automated DNA sequencer. For the three markers, frequencies of heterozygotes are well predicted from allele frequencies by the Hardy—Weinberg rule, which suggests that problems of allele nonamplification are unlikely. Typing of cell lines homozygous in the HLA region allowed unambiguous definition of 81 HLA-MOG haplotypes and showed that several HLA ancestral haplotypes extended to the MOG region. The high degree of polymorphism (59%, 51%, and 81% at the three loci, respectively, and 87% at the haplotype level) makes these new markers informative for association or linkage studies with diseases such as hemochromatosis or multiple sclerosis, and for studies aimed at precisely delineating the site of crossover in chromosomes in which recombination occurred in the distal part of the HLA class I region.  相似文献   
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