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1.
DNase activity was analyzed in 110 IgG preparations from the blood of AIDS patients. The relative activity of the preparations varied markedly among patients, being reliably detectable in 96% of the preparations. It was shown with several rigid criteria that DNAase activity is an intrinsic property of antibodies (Abs) from AIDS patients. Not only intact IgG, but also isolated light chains of polyclonal Abs were shown to possess catalytic activity. The abzymes efficiently catalyzed DNA hydrolysis in a wide range of pH (5.0–9.5). The K M and V max values were evaluated for Ab-dependent hydrolysis of DNA.  相似文献   

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DNase autoantibodies (Abzs) can be found in the blood of patients with several autoimmune diseases, while the blood of healthy donors or patients with diseases with an insignificant disturbance of the immune status does not contain DNase Abzs. Here we present the first analysis of the DNase Abzs activity in the patients with tick-borne encephalitis (TBE). Several strict criteria have been applied to show that the DNase activity is an intrinsic property of IgGs from the sera of TBE patients but not from healthy donors. The relative activity of IgGs has been shown to vary extensively from patient to patient, but most of the preparations (91%) had detectable levels of the DNase activity. Polyclonal DNase IgGs were not active in the presence of EDTA or after a dialysis against EDTA, but could be activated by several externally added metal ions, with the level of activity decreasing in the order Mn2+ + Ca2+ ≥ Mn2++ Mg2+ ≥ Mn2+ ≥ Mg2+ + Ca2+ ≥ Co2+ ≥ Mg2+ > Ca2+, while K+, Na+, Ni2+, Zn2+, and Cu2+ did not stimulate DNA hydrolysis. Affinity chromatography on DNA-cellulose separated the DNase IgGs into many subfractions with various affinities for DNA and very different levels of the relative activity. Possible reasons for catalytic diversity of polyclonal human Abzs are discussed.  相似文献   

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Acquired immune deficiency syndrome (AIDS), caused by infection with human immunodeficiency virus (HIV), is associated with gastrointestinal disease, systemic immune activation and changes in the gut microbiota. Here, we aim to investigate the gut microbiota patterns of HIV‐infected individuals and HIV‐uninfected individuals in populations from South China. We enrolled 33 patients with HIV (14 participants treated with highly active antiretroviral therapy [HAART] for more than 3 months; the remaining 19 individuals had not received treatment) and 35 healthy controls (HC) for a cross‐sectional comparison of gut microbiota using stool samples. Gut microbial communities were profiled by sequencing the bacterial 16S rRNA genes. Dysbiosis was more common among patients with AIDS compared with healthy individuals. Dysbiosis was characterized by decreased α‐diversity, low mean counts of Bacteroidetes, Faecalibacterium, Prevotella, Bacteroides vulgatus, Dialister and Roseburia inulnivorans, and high mean counts of Proteobacteria, Enterococcus, Streptococcus, Lactobacillus, Lachnociostridium, Ruminococcus gnavus and Streptococcus vestibularis. Increased abundance of Bacilli was observed in homosexual patients. Proteobacteria were higher among heterosexual patients with HIV infections. Tenericutes were higher among patients with history of intravenous drug abuse. Restoration of gut microbiota diversity and a significant increase in abundance of Faecalibacterium, Blautia and Bacteroides were found in patients receiving HAART compared to those who did not receive. HIV infection‐associated dysbiosis is characterized by decreased levels of α‐diversity and Bacteroidetes, increased levels of Proteobacteria and the alterations of gut microbiota correlate with the route of HIV transmission. The imbalanced faecal microbiota of HIV infection is partially restored after therapy.  相似文献   

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Four fractions of IgG antibodies to native DNA (nDNA) were obtained from blood of patients with systemic lupus erythematosus (SLE). These antibodies displayed a thermostable DNA-hydrolyzing activity and were different in affinity for DNA-cellulose and sorption on DEAE-cellulose. DNA-hydrolyzing antibodies to nDNA are metal-dependent endonucleases, cause mainly single-strand breaks in DNA, and are active over a wide range of pH. By atomic-force microscopy, three-dimensional images of DNA complexes with DNA-hydrolyzing antibodies to nDNA were obtained with nanometer resolution, and a nonprocessive action mechanism was shown for the DNase activity of antibodies to nDNA.  相似文献   

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Murine models for acquired immune deficiency syndrome   总被引:1,自引:0,他引:1  
R R Watson 《Life sciences》1989,44(3):iii-ixv
The mouse has been suggested as a host for comparative studies of several aspects of Human Acquired Immune Deficiency Syndrome (AIDS). Models include studies where part or all of the genome of Human Immunodeficiency Virus (HIV) has been incorporated into murine DNA in living mice. However, the most promising opportunities for study of immunological changes, vaccine development, cofactor involvement in disease, and anti-retroviral and immunostimulatory drug testing involve infection with murine retroviruses which cause many functional changes similar to AIDS. The viruses' effects on immune systems are reviewed with special emphasis. LP-BM5 murine leukemia virus which infects T and B cells, and macrophages. LP-BM5 infection suppresses cell functions while causing polyclonal lymphocyte activation. Murine immunological characterization, availability of inbred mouse strains, economy of using mice versus primates or humans models, and similarity of immune change caused by murine retroviruses compared to those seen in AIDS caused by HIV encourage rapid development of the LP-BM5 murine leukemia model.  相似文献   

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An analysis of the lengths of survival of patients with the acquired immune deficiency syndrome presenting with different opportunistic diseases was performed using epidemiological data routinely collected at the PHLS Communicable Disease Surveillance Centre. The overall crude case fatality rate was 55.4% (93/168). The median survival times were: 21.2 months for Kaposi''s sarcoma, 12.5 months for Pneumocystis carinii pneumonia, and 13.3 months for other opportunistic infections. The shortest median survival time (6.6 months) was found for those with both Kaposi''s sarcoma and P carinii pneumonia. There were significant differences between durations of survival of patients with Kaposi''s sarcoma and those with all other diseases, which indicated impaired cellular immunity apart from opportunistic infections. This analysis shows that those with Kaposi''s sarcoma alone have the most favourable prognosis.  相似文献   

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Polyunsaturated fatty acids (PUFAs) are known to modulate the immune system in vivo and to inactivate envelope viruses in vitro. Patients with AIDS had low total plasma lipid levels and low levels of a number of individual fatty acids. However, the C20 and C22 essential fatty acids of the n-3 series were selectively and highly significantly reduced. Normalization of these fatty acid levels in AIDS patients may be a worthwhile therapeutic aim.  相似文献   

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While Kaposi's sarcoma in patients with the acquired immune deficiency syndrome (AIDS) may present as a multicentric disease with progressive organ involvement, the classic form of Kaposi's sarcoma is an indolent tumor seldom affecting extracutaneous areas and almost never responsible for the patient's demise. An attempt was made to correlate these clinical differences with the nuclear DNA content of tumor cells in histologic sections from 15 patients (9 with AIDS and 6 without AIDS). All tumors showed a similar DNA distribution pattern, with most cells appearing diploid, indicative of a low malignant potential. These findings indicate that Kaposi's sarcoma of both AIDS and non-AIDS patients is a tumor of intrinsically low malignancy and that lack of immune surveillance is most probably responsible for its aggressive biologic behavior in many AIDS patients.  相似文献   

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The simian immunodeficiency virus (SIV) of the common chimpanzee is widely acknowledged as the direct ancestor of HIV-1. There is increasing historical evidence that during the late 1950s, kidneys were routinely excised from central African chimpanzees by scientists who were collaborating with the polio vaccine research of Dr Hilary Koprowski, and sent - inter alia - to vaccine-making laboratories in the USA and Africa, and to unspecified destinations in Belgium. While there is no direct evidence that cells from these kidneys were used as a substrate for growing Dr Koprowski's oral polio vaccines, there is a startling coincidence between places in Africa where his CHAT vaccine was fed, and the first appearances in the world of HIV-1 group M and group-M-related AIDS. Because of the enormous implications of the hypothesis that AIDS may be an unintended iatrogenic (physician-caused) disease, it is almost inevitable that this theory will engender heated opposition from many of those in the scientific establishment, and those with vested interests.  相似文献   

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A case of pulmonary infection with Mycobacterium tuberculosis in a patient with the acquired immune deficiency syndrome (AIDS) was studied. Diagnosis of AIDS was confirmed by the finding of pulmonary M tuberculosis with oral and oesophageal candidiasis accompanied by characteristic immunological changes with evidence of infection with human T cell lymphotropic virus III. Treatment of this patient was complicated by an unusual drug interaction between rifampicin and ketoconazole, leading to subtherapeutic serum concentrations and poor clinical response to treatment. Intravenous treatment was more effective than oral treatment. This drug interaction should be studied in greater detail as ketoconazole and rifampicin may be used together to treat patients with candidiasis and infection with M tuberculosis.  相似文献   

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