Serological response against Mycobacterium avium complex glycolipid antigens in patients with acquired immunodeficiency syndrome

In 43 MAC infected patients (23 non-HIV and 20 AIDS) the IgG response against 3 BCG and 2 MAC antigens was assessed. The response to four antigens in patients with AIDS was considerably lower than in non-HIV infected patients. Therefore, antibody production against MAC glycolipid antigens was impaired in AIDS patients.     

Patterns of primary care of patients infected with human immunodeficiency virus.

To determine the patterns of care of patients infected with the human immunodeficiency virus (HIV), data from 2 sources were analyzed. Initial data obtained from the Washington State HIV/Acquired Immunodeficiency Syndrome (AIDS) Epidemiology Unit indicate that 46% of patients with class IV AIDS were seen by physicians who reported fewer than 5 patients with AIDS, and 68% of all Washington physicians who reported treating patients with AIDS have reported only 1 patient. Subsequent data obtained from a questionnaire distributed in 4 Northwest states suggest that 74% of primary care internists and 73% of family practitioners have some experience in caring for patients with HIV infection, but most of these physicians report fewer than 6 patients in the past 2 years. Although most providers seeing large numbers of HIV-infected patients in their practices were based in the region''s major metropolitan area, 59% of the internists and 55% of the family practitioners surveyed outside of the metropolitan area had seen at least 1 HIV-infected patient in their practices. These results suggest that primary care physicians with relatively little experience treating HIV infection are providing care for a large number of HIV-infected persons. Further study is needed to determine the extent and quality of care provided.     

Tryptophan degradation in patients infected by human immunodeficiency virus

Tryptophan and kynurenine were measured retrospectively in sera of 11 male patients with advanced human immunodeficiency virus (HIV) infection (Walter Reed stages 4 and 6). Tryptophan levels are significantly reduced to less than 50% in patients with HIV infection and kynurenine levels significantly elevated when compared to sex and age matched controls. The decrease of tryptophan levels might contribute to neurologic symptoms often associated with HIV infection. Since interferon-gamma induces degradation of tryptophan via the kynurenine pathway, the present results may be consistent with enhanced endogenous production of interferon-gamma in advanced HIV infection.     

Non-dermatophytic moulds: onychomycosis in four patients infected with the human immunodeficiency virus

Patients infected with human immunodeficiency virus (HIV) are a risk group for onychomycosis, fungal infections caused mainly by dermatophytes and yeast. However, non-dermatohytic moulds are becoming common agents for nail infections in this population of patients. We report four cases of onychomycosis caused by non-dermatophytic moulds (Aspergillus niger, Scytalidium hyalinum, Scytalidium dimidiatum and Fusarium solani) in patients infected with HIV from Recife, Pernambuco, Brazil. Onychomicosis by non-dermatophytic species in HIV-positive patients requires special attention in the clinical and the laboratory. A proper diagnosis is necessary to establish the specific and adequate treatment, preventing fungal invasion.     

Comparison between human immunodeficiency virus positive and negative patients with tuberculosis in Southern Brazil.

The objective of this study is to determine the different characteristics of human immunodeficiency virus (HIV) positive and negative patients treated for tuberculosis (TBC) in a tertiary hospital in Southern Brazil. We conducted a retrospective cohort study over a 5-year period, from January 1992 through December 1996. We reviewed medical charts of patients from our institution who received TBC treatment. We reviewed 167 medical charts of patients with confirmed TBC. HIV positivity was detected in 74 patients. There were statistically significant difference between HIV positive and negative patients in sex and age. HIV-infected patients showed significantly more signs of bacteremia than HIV-negative patients. Extra-pulmonary TBC was present respectively in 13 (17.6%) and 21 (22.6%) HIV positive and negative patients. There was a significant difference between chest radiograph presentation in HIV positive and negative patients. There were significantly lower hematocrit, hemoglobin, leukocyte and lymphocyte levels in HIV-positive compared to HIV-negative patients. Outcome was significantly different in the two groups with a death rate of 36.5% and 10.8% in HIV-positive and in HIV-negative patients. The difference between HIV positive and negative patients may have importance in the diagnosis, management and prognosis of patients with TBC.     

Selenium supplementation of symptomatic human immunodeficiency virus infected patients

The mean whole blood selenium levels in male San Diego, CA patients with acquired immune deficiency syndrome (AiDS) are 0.123 +/- 0.030 micrograms/mL (n = 24), and 0.126 +/- 0.038 micrograms/mL (n = 26) in patients with AIDS-related complex (ARC), compared to 0.195 +/- 0.020 micrograms/mL (n = 28) in San Diego healthy controls (males). To establish whether intestinal absorption of dietary selenium is impaired in AIDS or ARC, a supplementation trial was conducted in which 19 symptomatic HIV-antibody positive male patients with AIDS or ARC were taking 400 micrograms of selenium/d in form of selenium yeast for up to 70 d. The mean whole blood Se levels increased to 0.28 +/- 0.08 micrograms/mL after 70 d of supplementation, the selenium supplements were well tolerated. A rationale for adjuvant selenium supplementation of symptomatic and asymptomatic HIV carriers is proposed.     

Primary care physicians' refusal to care for patients infected with the human immunodeficiency virus.

We conducted a telephone survey of a random sample of office-based primary care physicians in Los Angeles County to determine their practice experiences with patients infected with the human immunodeficiency virus (HIV). Telephone interviews included questions related to the physicians'' experiences evaluating patients for HIV infection during the past 6 months and the presence of HIV-infected patients in their practices. Those without HIV-infected patients were asked if this was because they had not encountered such patients, because those patients had died, or because the physicians had chosen to refer these patients elsewhere or the patients had gone elsewhere for care. Of physicians who participated in the survey, 78% had evaluated a patient for HIV infection in the past 6 months; 34% were currently providing primary care for infected patients; and 36% had elected to refer HIV-infected patients elsewhere, or their patients had elected to find other physicians. In all, 48% of physicians in the sample had elected not to care for, or said they would not provide care for, patients with HIV infection. Among Los Angeles County primary care physicians, 36% have refused to provide continuing care for HIV-infected patients and another 12% indicated their unwillingness to do so should such patients present themselves for care. As of 1991, the reservoir of primary care physicians in Los Angeles not yet involved with but willing to care for HIV-infected patients is relatively small (15%).     

Polyamines in lymphocytes from patients infected by human immunodeficiency virus

Lymphocytes from patients with antibodies against the AIDS associated human immuno-deficiency virus (HIV-1) have elevated concentrations of polyamines. Spermidine and spermine are similar in amount in patients with Persistent Generalized Lymphadenopathy (PGL) and overt AIDS, while putrescine is much higher in the latter. Spermidine-acetyltransferase activity is also increased in lymphocytes from patients with PGL. Diamine-oxidase activity is decreased in serum of patients with PGL, but not in those with AIDS.     

Comparative profiles of intramacrophage behavior of Mycobacterium tuberculosis and Mycobacterium avium complex with different levels of virulence

Mycobacterium tuberculosis (MTB) and M. avium complex (MAC) strains with different levels of virulence in mice were examined for profiles of interaction with murine peritoneal macrophages (Mphis). Their growth rates in Mphis were in these orders: H37Ra strain (attenuated) > H37Rv strain (virulent) for MTB, and N-260 strain (moderate virulence) > MAC N-444 strain (low virulence) for MAC. MTB but not MAC caused the necrotic death of host Mphis in terms of increased release of lactate dehydrogenase from infected Mphis. The MTB H37Ra strain induced a greater production of reactive nitrogen intermediates (RNI) by Mphis than the MTB H37Rv strain did. However, this phenomenon was not observed with MAC, implying less important roles of RNI in the expression of Mphi antimicrobial activity against MAC organisms.     

Comparison of three DNA extraction methods for Mycobacterium bovis, Mycobacterium tuberculosis and Mycobacterium avium subsp. avium

Aims:  To compare three methods for DNA extraction from Mycobacterium bovis , Mycobacterium tuberculosis and Mycobacterium avium subsp. avium .
Methods and Results:  The DNA was extracted from mycobacterial cultures using enzymatic extraction, combined bead beating and enzymatic extraction and cetyltrimethylammonium bromide (CTAB) extraction. The yield and quality of DNA were compared by spectrophotometry, agarose gel electrophoresis, restriction endonuclease analysis and PCR. The combined bead beating and enzymatic extraction method yielded more DNA. However, that method produced some sheared DNA, visible either by agarose gel electrophoresis or by restriction endonuclease analysis. All methods were appropriate for PCR amplification of a 123 bp fragment of IS 6110 in M. bovis and M. tuberculosis , and of a 1700 bp fragment of FR300 region in M. avium avium .
Conclusions:  Combined bead beating and enzymatic extraction method was the most efficient and easy method for extracting DNA from bacteria of the M. tuberculosis complex.
Significance and Impact of the Study:  The results reveal important differences among the DNA extraction methods for mycobacteria, which are relevant for the success of further downstream molecular analysis.     

Sequence-based differentiation of strains in the Mycobacterium avium complex.

The complete 16S-23S rDNA internal transcribed spacer (ITS) was sequenced in 35 reference strains of the Mycobacterium avium complex. Twelve distinct ITS sequences were obtained, each of which defined a "sequevar"; a sequevar consists of the strain or strains which have a particular sequence. ITS sequences were identified which corresponded to M. avium (16 strains, four ITS sequevars) and Mycobacterium intracellulare (12 strains, one ITS sequevars). The other seven M. avium complex strains had ITS sequences which varied greatly from those of M. avium and M. intracellulare and from each other. The 16S-23S rDNA ITS was much more variable than 16S rDNA, which is widely used for genus and species identification. Phylogenetic trees based on the ITS were compatible with those based on 16S rDNA but were more detailed and had longer branches. The results of ITS sequencing were consistent with the results of hybridization with M. avium and M. intracellulare probes (Gen-Probe) for 30 of 31 strains tested. Serologic testing correlated poorly with ITS sequencing. Strains with the same sequence were different serovars, and those of the same serovar had different sequences. Sequencing of the 16S-23S rDNA ITS should be useful for species and strain differentiation for a wide variety of bacteria and should be applicable to studies of epidemiology, diagnosis, virulence, and taxonomy.     

获得性免疫缺陷综合征患者的新生隐球菌基因多态性研究

本文旨在调查2003 年1 月― 2007 年12 月分离自上海地区获得性免疫缺陷综合征( AIDS) 患者的新生隐球菌临床株的配型及基因型分布特征, 为隐球菌病的诊疗提供科学依据。首先以M13 为单引物对模板DNA 进行聚合酶链反应( PCR) 扩增, 参照标准株指纹图将临床株鉴定至基因型; 同时对12 株来自AIDS 患者的新生隐球菌临床株的内转录间隔区( ITS) 基因进行PCR 扩增、序列分析, 以CLUSTAL W1. 83 软件多重比对分析ITS序列的差别,MEGA3. 1 软件处理数据, NJ 法绘制系统进化树, Bootstrapping 法对系统进化树结果进行统计学检验, 区分新生隐球菌格鲁比变种、新生变种及格特变种菌株; 最后选用特异性引物PCR 特异性扩增相关基因, 鉴定α和a 配型。结果显示, 分离自上海地区的12 株隐球菌临床株中, 9 株( 75% ) 为VNⅠ基因型/ α配型菌株,3 株( 25%) 为VNⅡ基因型/ α配型菌株, 且ITS基因序列分析可将各临床株鉴定至变种水平。本研究提示, 分离自上海地区AIDS患者的新生隐球菌临床株存在一定的遗传多态性, 以VNⅠ基因型/ α配型菌株为主, 有少量VNⅡ基因型/ α配型菌株。     

Culture and molecular method for detection of Mycobacterium tuberculosis complex and Mycobacterium avium subsp. paratuberculosis in milk and dairy products

A combined molecular and cultural method for the detection of the Mycobacterium tuberculosis complex (MTBC) and Mycobacterium avium subsp. paratuberculosis was developed and tested with artificially contaminated milk and dairy products. Results indicate that the method can be used for a reliable detection as a basis for first risk assessments.     

Autophagy induction by vitamin D inhibits both Mycobacterium tuberculosis and human immunodeficiency virus type 1

Low vitamin D levels in human immunodeficiency virus type-1 (HIV) infected persons are associated with more rapid disease progression and increased risk for Mycobacterium tuberculosis infection. We report that physiological concentrations of 1α,25-dihydroxycholecalciferol (1,25D3), the active form of vitamin D, inhibits M. tuberculosis and HIV replication in co-infected macrophages through human cathelicidin microbial peptide-dependent autophagy that requires phagosomal maturation. These findings provide a biological explanation for the importance of vitamin D sufficiency in HIV and M. tuberculosis-infected persons, and provide new insights into novel approaches to prevent and treat HIV infection and related opportunistic infections.     

Autophagy induction by vitamin D inhibits both Mycobacterium tuberculosis and human immunodeficiency virus type 1

Low vitamin D levels in human immunodeficiency virus type-1 (HIV) infected persons are associated with more rapid disease progression and increased risk for Mycobacterium tuberculosis infection. We report that physiological concentrations of 1α,25-dihydroxycholecalciferol (1,25D3), the active form of vitamin D, inhibits M. tuberculosis and HIV replication in co-infected macrophages through human cathelicidin microbial peptide-dependent autophagy that requires phagosomal maturation. These findings provide a biological explanation for the importance of vitamin D sufficiency in HIV and M. tuberculosis-infected persons, and provide new insights into novel approaches to prevent and treat HIV infection and related opportunistic infections.     

Prevalence of moderate and severe depression among Croatian patients infected with human immunodeficiency virus

The aim of the study was to assess the prevalence of depression among Croatian patients infected with human immunodeficiency virus (HIV) and to make a comparison with patients with other acute and chronic infectious diseases. We assessed the depressive disorder using the Beck Depression Inventory questionnaire (BDI), without clinical confirmation. The BDI scores were examined in 80 HIV-infected persons and compared to 80 persons with chronic viral hepatitis and 78 with acute infectious diarrhea. All examinees were treated as outpatients at the University Hospital for Infectious Diseases in Zagreb in March and April of 2003. Prevalence of moderate and severe depression among HIV-infected was 16/80 (20%) with a 95% confidence interval 11% to 29%. Male patients with HIV or chronic viral hepatitis had a significantly higher BDI scores than males with acute infectious diarrhea (p = 0.017, Kruskall-Wallis, d.f. 2). Female patients with HIV infection tended to have a lower BDI score than females with chronic viral hepatitis or acute infectious diarrhea (p = 0.087, Kruskall-Wallis, d.f. 2). Prevalence of moderate and severe depression among Croatian HIV-positive patients is higher than the upper estimate for general population. Croatian males with chronic infectious disease have higher rate of depression than those with acute infectious disease.     

Variation in mannose-capped terminal arabinan motifs of lipoarabinomannans from clinical isolates of Mycobacterium tuberculosis and Mycobacterium avium complex

The unique terminal arabinan motifs of mycobacterial lipoarabinomannan (LAM), which are mannose-capped to different extents, probably constitute the single most important structural entity engaged in receptor binding and subsequent immunopathogenesis. We have developed a concerted approach of endoarabinanase digestion coupled with chromatography and mass spectrometry analysis to rapidly identify and quantitatively map the complement of such terminal units among the clinical isolates of different virulence and drug resistance profiles. In comparison with LAM from laboratory strains of Mycobacterium tuberculosis, an ethambutol (Emb) resistant clinical isolate was shown to have a significantly higher proportion of nonmannose capped arabinan termini. More drastically, the mannose capping was completely inhibited when an Emb-susceptible strain was grown in the presence of subminimal inhibitory concentration of Emb. Both cases resulted in an increase of arabinose to mannose ratio in the overall glycosyl composition of LAM. Emb, therefore, not only could affect the complete elaboration of the arabinan as found previously for LAM from Mycobacterium smegmatis resistant mutant but also could inhibit the extent of mannose capping and hence its associated biological functions in M. tuberculosis. Unexpectedly, an intrinsically Emb-resistant Mycobacterium avium isolate of smooth transparent colony morphology was found to have most of its arabinan termini capped with a single mannose residue instead of the more common dimannoside as established for LAM from M. tuberculosis. This is the first report on the LAM structure from M. avium complex, an increasingly important opportunistic infectious agent afflicting AIDS patients.     

Mycobacterium tuberculosis and Mycobacterium avium modify the composition of the phagosomal membrane in infected macrophages by selective depletion of cell surface-derived glycoconjugates

The growth of pathogenic mycobacteria in phagosomes of the host cell correlates with their ability to prevent phagosome maturation. The underlying molecular mechanism remains elusive. In a previous study, we have shown that Mycobacterium avium depletes the phagosome membrane of cell surface-derived glycoconjugates (de Chastellier and Thilo, Eur. J. Cell Biol. 81, 17-25, 2002). We now extended these quantitative observations to the major human pathogen, Mycobacterium tuberculosis (H37Rv). At increasing times after infection of mouse bone marrow-derived macrophages, cell-surface glycoconjugates were labelled enzymatically with [3H]galactose. Subsequent endocytic membrane traffic resulted in a redistribution of this label from the cell surface to endocytic membranes, including phagosomes. The steady-state distribution was measured by quantitative autoradiography at the electron microscope level. Relative to early endosomes, with which phagosomes continued to fuse and rapidly exchange membrane constituents, the phagosome membrane was depleted about 3-fold, starting during infection and in the course of 9 days thereafter. These results were in quantitative agreement with our previous observations for Mycobacterium avium. For the latter case, we now showed by cell fractionation that the depletion was selective, mainly involving glycoproteins in the 110-210 kDa range. Together, these results indicated that pathogenic mycobacteria induced and maintained a bulk change in phagosome membrane composition that could be of special relevance for survival of pathogenic mycobacteria within phagosomes.