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141.
Campbell TB Fitzpatrick L MaWhinney S Zhang X Schooley RT 《Journal of acquired immune deficiency syndromes (1999)》1999,22(4):333-340
OBJECTIVE: To determine the prevalence of human herpesvirus 8 (HHV-8) infection in men treated for HIV-1 infection in Denver, Colorado. DESIGN: Cross-sectional analysis METHODS: Blood samples were obtained from 216 HIV-1-infected men. Antibody to latency-associated nuclear antigen (LANA) was detected by an immunofluorescent assay and the presence of HHV-8 in peripheral blood mononuclear cells (PBMC) was detected by polymerase chain reaction amplification. RESULTS: Among HIV-1-infected men who did not have Kaposi's sarcoma (KS), prevalence of HHV-8 infection was 46% (95% confidence interval [CI], 0.39-0.52). LANA seropositivity was common both among subjects with KS and subjects without KS (69% versus 42%; p = .06), but detection of HHV-8 DNA in peripheral blood was strongly associated with a diagnosis of KS (44% versus 10%; p = .001). In a univariate analysis of study subjects without KS, neither the odds of LANA seropositivity nor detection of HHV-8 DNA in PBMC was significant for CD4+ lymphocyte count, HIV-1 virus load, the use of three drug antiretroviral regimens or the prior occurrence of non-KS AIDS-related conditions. CONCLUSION: Although antibodies to HHV-8 are common among HIV-1-infected men, detection of HHV-8 DNA in PBMC is uncommon and is associated with a diagnosis of Kaposi's sarcoma. 相似文献
142.
Relation between gastric histology and gastric juice pH and nitrite and N-nitroso compound concentrations in the stomach after surgery for duodenal ulcer 下载免费PDF全文
P C Watt J M Sloan J Donaldson G Campbell T L Kennedy 《Journal of clinical pathology》1984,37(5):511-515
Formation of N-nitroso compounds in gastric juice has been implicated in the pathogenesis of cancer in the stomach after operation. Gastric juice was aspirated from 85 subjects: 23 were controls, 51 had previously undergone vagotomy and gastrojejunostomy, and 11 had previously undergone vagotomy and pyloroplasty. The gastric juice samples were analysed for pH, nitrite, and total N-nitroso compounds. A significant correlation was found between pH and nitrite concentration (p less than 0.01). No significant correlation was found between pH and total N-nitroso compound concentration or between nitrite and N-nitroso compound concentration. The vagotomy and gastrojejunostomy patients had higher pH values and higher concentrations of nitrites and N-nitroso compounds than controls (p = 0.01 in all cases). The 51 vagotomy and gastrojejunostomy patients also underwent endoscopy and biopsy. They were divided into three groups: group 1 (21 patients) had no intestinal metaplasia and no more than mild dysplasia; group 2 (20 patients) had intestinal metaplasia; and group 3 (10 patients) had moderate or severe dysplasia. Groups 2 and 3 both had higher pH values and higher nitrite concentrations than group 1 (p = 0.01 in all cases). There was no significant difference, however, between either group 2 or 3 and group 1 for total N-nitroso compound concentration. Since there was no simple linear relation between pH and N-nitroso compound concentration, it was concluded that formation of N-nitroso compounds at high pH was unlikely to be involved in the pathogenesis of gastric cancer in the hypochlorhydric stomach after operation. The relation between nitrite and histological abnormality was not associated with a similar relation between N-nitroso compounds and histological abnormality. It therefore appears that there is no simple relation between N-nitroso compounds and the pathogenesis of premalignant gastric mucosal changes. 相似文献
143.
144.
M J Coppes L Bonetta A Huang P Hoban S Chilton-MacNeill C E Campbell R Weksberg H Yeger A E Reeve B R Williams 《Genes, chromosomes & cancer》1992,5(4):326-334
Loss of heterozygosity (LOH) for polymorphic markers is a frequently occurring event in some tumors, reflecting the role of allele loss in the development of these tumors. We have determined LOH in 38 cases of Wilms tumor for the 2 known loci on chromosome arm 11p and for a newly detected locus on chromosome arm 16q. Only 7 of the 38 tumors studied showed reduction to homozygosity of 11p13 markers. In 4 of these tumors, reduced expression of WT1 and WIT1, genes located at 11p13 and implicated in Wilms tumorigenesis, was noted. However, this was also found in 2 of 7 tumors showing LOH exclusively of 11p15 markers and in 15 of the remaining 24 tumors in which there was no LOH for 11p markers. This suggests that events not involving mitotic recombination or chromosome nondisjunction are the most common mechanisms for mutations at the 11p Wilms tumor locus. We also noted that mitotic recombination involving 11p15 loci occurred in addition to reduced expression of the 11p13 locus genes in 2 tumors, suggesting a possible interaction between these 2 loci. In addition, LOH for 16q markers was observed in 6 tumors. In one case this was coincident with reduction of WT1 and WIT1 gene expression, and in 3 other cases it occurred in addition to 11p LOH. This indicates that an additional locus on 16q is likely to be involved in Wilms tumorigenesis. 相似文献
145.
Expression of the chemokine receptors CCR4, CCR5, and CXCR3 by human tissue-infiltrating lymphocytes. 总被引:17,自引:0,他引:17 下载免费PDF全文
Eric J Kunkel Judie Boisvert Kristine Murphy Mark A Vierra Mark C Genovese Andrew J Wardlaw Harry B Greenberg Martin R Hodge Lijun Wu Eugene C Butcher James J Campbell 《The American journal of pathology》2002,160(1):347-355
Differential expression of adhesion molecules and chemokine receptors has been useful for identification of peripheral blood memory lymphocyte subsets with distinct tissue and microenvironmental tropisms. Expression of CCR4 by circulating memory CD4(+) lymphocytes is associated with cutaneous and other systemic populations while expression of CCR9 is associated with a small intestine-homing subset. CCR5 and CXCR3 are also expressed by discrete memory CD4(+) populations in blood, as well as by tissue-infiltrating lymphocytes from a number of sites. To characterize the similarities and differences among tissue-infiltrating lymphocytes, and to shed light on the specialization of lymphocyte subsets that mediate inflammation and immune surveillance in particular tissues, we have examined the expression of CCR4, CXCR3, and CCR5 on CD4(+) lymphocytes directly isolated from a wide variety of normal and inflamed tissues. Extra-lymphoid tissues contained only memory lymphocytes, many of which were activated (CD69(+)). As predicted by classical studies, skin lymphocytes were enriched in CLA expression whereas intestinal lymphocytes were enriched in alpha(4)beta(7) expression. CCR4 was expressed at high levels by skin-infiltrating lymphocytes, at lower levels by lung and synovial fluid lymphocytes, but never by intestinal lymphocytes. Only the high CCR4 levels characteristic of skin lymphocytes were associated with robust chemotactic and adhesive responses to TARC, consistent with a selective role for CCR4 in skin lymphocyte homing. In contrast, CXCR3 and CCR5 were present on the majority of lymphocytes from each non-lymphoid tissue examined, suggesting that these receptors are unlikely to determine tissue specificity, but rather, may play a wider role in tissue inflammation. 相似文献
146.
Heat shock protein 70 (HSP70) and complement C4 genotypes in patients with hyperthyroid Graves'' disease. 下载免费PDF全文
S Ratanachaiyavong A G Demaine R D Campbell A M McGregor 《Clinical and experimental immunology》1991,84(1):48-52
The genetic polymorphisms of the heat shock protein 70 (HSP70) and complement component C4 were investigated in 90 patients with hyperthyroid Graves' disease and 92 normal control subjects. The 8.5-kb PstI HSP70 allele was strongly associated with Graves' disease when compared with controls (P less than 0.001). The presence of the 8.5-kb PstI HSP70 allele was strongly associated with a deletion of the C4A gene in both patients and controls (P less than 0.0003 and P less than 0.00005 respectively). However, in the absence of C4A gene deletion, the frequency of the 8.5-kb PstI HSP70 allele was still significantly higher in patients when compared with controls (P less than 0.04). These results suggest that the HSP70 locus may have an immunological role to play in autoimmune hyperthyroid Graves' disease. 相似文献
147.
Virulence Differences in Mice of Type A and B Histoplasma capsulatum Yeasts Grown in Continuous Light and Total Darkness 总被引:1,自引:1,他引:1 下载免费PDF全文
Type B yeasts were more virulent for mice than type A under most experimental conditions. Mice infected with type B yeasts grown in the light lived significantly longer than those with type B yeasts grown in the dark. Virulence differences of type A yeasts grown in continuous fluorescent light versus total darkness were not statistically significant. 相似文献
148.
Collagen-induced arthritis in C57BL/6 (H-2b) mice: new insights into an important disease model of rheumatoid arthritis 总被引:10,自引:0,他引:10
Collagen-induced arthritis (CIA) is a widely used model of rheumatoid arthritis (RA) and has been important for understanding autoimmunity. CIA is purportedly restricted to mice bearing the MHC class II H-2q or H-2r haplotypes. In this study, we re-examined established concepts regarding susceptibility to CIA. We found mice derived from the C57BU6 (B6) (H-2b) background can develop CIA with high incidence (60-70%), and sustained severity by using an immunization procedure modified for optimum response in DBA/1 (D1) (H-2q) mice. Clinically and histologically the B6 disease resembles that of D1 mice and is dependent on immunization with type II collagen, as well as on B and CD4+ T cells. In contrast, 129/Sv mice, which share H-2b, are resistant to CIA. We conclude that susceptibility to CIA may reflect immunization conditions and/or important contributions from non-MHC genes, revealed by different immunization protocols. A practical outcome is that CIA can be directly applied to gene knockout mice generated from B6 embryonic stem cells without need for backcross onto the D1 background. This model may lead to improved understanding of autoimmunity in CIA and RA and may provide a platform for analysis of the contribution of non-MHC genes to CIA. 相似文献
149.
Coxsackievirus B3-Induced Myocarditis : Perforin Exacerbates Disease, But Plays No Detectable Role in Virus Clearance 总被引:8,自引:3,他引:8 下载免费PDF全文
John R. Gebhard Christopher M. Perry Stephanie Harkins Thomas Lane Ignacio Mena Valrie C. Asensio Iain L. Campbell J. Lindsay Whitton 《The American journal of pathology》1998,153(2):417-428
Viral myocarditis is remarkably common, being detected in approximately 1% of unselected asymptomatic individuals. Many cases are attributable to enteroviral infection, and in particular to coxsackievirus B3. The underlying pathogenesis is controversial, but most studies admit the important immunopathological role of infiltrating CD8+ (cytotoxic) T lymphocytes (CTLs). We have previously shown that CTLs play conflicting roles in coxsackievirus B (CVB) myocarditis; they assist in controlling virus replication, but also are instrumental in causing the extensive inflammatory disease, which often results in severe myocardial scarring. A role for perforin, the major CTL cytolytic protein, in CVB myocarditis has been suggested, but never proven. In the present study we use perforin knockout (PKO) mice to show that perforin plays a major role in CVB infection; in broad terms, perforin is important in immunopathology, but not in CVB clearance. For example, PKO mice are better able to withstand a normally lethal dose of CVB (100% survival of PKO mice compared with 90% death in +/+ littermates). In addition, PKO mice given a nonlethal dose of CVB develop only a mild myocarditis, whereas their perforin+ littermates have extensive myocardial lesions. The myocarditis in PKO mice resolves more quickly, and these mice show minimal histological sequelae; in contrast, late in disease the perforin+ mice develop severe myocardial fibrosis. PKO mice, despite lacking this major CTL effector function, can control the infection and eradicate the virus; growth kinetics and peak CVB titers are indistinguishable in PKO and perforin+ mice. Therefore, the immunopathological and antiviral effects of CTLs can be uncoupled by ablation of perforin; this offers a promising target for therapy of myocarditis. Furthermore, we evaluate the possible roles of apoptosis, and of chemokine expression, in CVB infection. In perforin+ mice, apoptotic cells are detected within the inflammatory infiltrate, whereas in their PKO counterparts, apoptotic myocyte nuclei are seen. Chemokine expression in both PKO and perforin+ mice precedes and parallels the course of myocarditis. Several chemokines are detectable earlier in PKO mice than in perforin+ mice, but PKO mice show reduced peak levels, and chemokine expression decays sooner. In particular, MIP-1α expression is barely detectable at any time point in PKO mice, but it is readily identified in perforin+ animals, peaking just before the time of maximal myocarditis; this is particularly interesting, given that MIP-1α knockout mice are resistant to CVB myocarditis, but remain able to control viral infection. Thus, the chemokine pathway offers a second route of intervention to diminish myocarditis and its sequelae, while permitting the host to eradicate the virus. 相似文献
150.