Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026918 (Mycobacterium)
 52,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

IgG antibodies against the 2,3-di-o-acyltrehalose glycolipid of Mycobacterium tuberculosis were determined in a set of 49 sera from patients with pulmonary tuberculosis and 65 negative control subjects. We compared a conventional ELISA method using a beta-galactosidase anti-human IgG conjugate developed with ONPG, with an amplification ELISA system constituted of an anti-human IgG biotinylated conjugate, a streptavidin-alkaline phosphatase complex, and NADP as a substrate. The resulting NAD was measured by using a redox enzymatic recycling system of alcohol dehydrogenase, diaphorase and iodonitrotetrazolium as chromogen. With specificity set at 92.31% in both methods, we obtained a sensitivity of 42.86% in the conventional method and a sensitivity of 61.22% in the amplified method. We conclude that by using a more sensitive method we can detect cases that otherwise could be identified as false negatives.
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PMID:Development of an enzyme-linked immunosorbent assay (ELISA) combined with a streptavidin-biotin and enzyme amplification method to detect anti-2,3-di-o-acyltrehalose (DAT) antibodies in patients with tuberculosis. 782 39

A mycobacterial expression-secretion vector was constructed in which the Escherichia coli alkaline phosphatase (phoA) reporter gene was placed under the control of the Mycobacterium tuberculosis 85A promoter and secretion signal sequences. In recombinant Mycobacterium smegmatis and Mycobacterium bovis BCG, PhoA activity could readily be detected on the mycobacterial cell surface and in the culture supernatant, indicating that the 85A signals can drive heterologous expression and secretion in both species. In contrast to the mycobacteria, the 85A promoter did not function in E. coli. We mapped the promoter region by progressive deletions using BAL 31 exonuclease and by primer extension analysis. Insertion and deletion mutations within the promoter region indicated that, unlike most E. coli promoters but similar to Streptomyces promoters, the position of the putative -35 region was not critical for efficient promoter activity. In addition, we investigated the ability of the identified signals to drive the production and secretion in BCG of recombinant Schistosoma mansoni glutathione S-transferase (Sm28GST), a protective antigen against schistosomiasis. BALB/c mice immunized with the recombinant BCG by a single dose exhibited a weak but specific T-cell response to Sm28GST.
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PMID:Analysis of the Mycobacterium tuberculosis 85A antigen promoter region. 783 98

The gene encoding a class A beta-lactamase was cloned from a natural isolate of Mycobacterium fortuitum (blaF) and from a high-level amoxicillin-resistant mutant that produces large amounts of beta-lactamase (blaF*). The nucleotide sequences of the two genes differ at 11 positions, including two in the region upstream from the coding sequence. Gene fusions to Escherichia coli lacZ and transcription and expression analysis of the cloned genes in Mycobacterium smegmatis indicated that high-level production of the beta-lactamase in the mutant is mainly or wholly due to a single base pair difference in the promoter. These analyses also showed that transcription and translation start at the same position. A comparison of the amino acid sequence of BlaF, as predicted from the nucleotide sequence, with the determined N-terminal amino acid sequence indicated the presence of a typical signal peptide. The fusion of blaF (or blaF*) to the E. coli gene phoA resulted in the production of BlaF-PhoA hybrid proteins that had alkaline phosphatase activity. These results demonstrate that phoA can be used as a reporter gene for studying protein export in mycobacteria.
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PMID:Transcription and expression analysis, using lacZ and phoA gene fusions, of Mycobacterium fortuitum beta-lactamase genes cloned from a natural isolate and a high-level beta-lactamase producer. 806 66

Forty-seven paired specimens of ileum and mesenterial lymph nodes from goats originating from 2 herds with paratuberculosis were investigated. Culture of the specimens for Mycobacterium paratuberculosis was compared with Ziehl-Neelsen staining and with immunohistochemical tests on paraffin-embedded tissue sections, using a M. paratuberculosis immune serum and an avidin-biotin-alkaline phosphatase method. Immunohistochemical techniques detected most positive samples and produced more clearly visible reactions than did acid-fast staining. Eighteen of 47 samples were positive by immunohistochemical techniques may represent a valuable adjunct to standard techniques for diagnosis of paratuberculosis in goats.
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PMID:Comparison of immunohistochemistry, acid-fast staining, and cultivation for detection of Mycobacterium paratuberculosis in goats. 806 51

Strand displacement amplification, a new isothermal in vitro DNA amplification technique, was used to amplify target DNA contained within the IS6110 insertion element of the species within the Mycobacterium complex (Mycobacterium tuberculosis, M. bovis, M. bovis-BCG, M. africanum and M. microti). The target nucleic acid sequence is present in approximately ten, two, one, five and five copies in M. tuberculosis, M. bovis, M. bovis-BCG, M. africanum and M. microti, respectively. Amplified products were detected using a non-isotopic microtitre plate assay employing a biotinylated oligodeoxynucleotide probe and an alkaline phosphatase conjugated oligodeoxynucleotide probe. Lumiphos 530 was the chemiluminescent substrate for alkaline phosphatase. The combination of the strand displacement amplification method with this sensitive and rapid (less than 2 h) detection system resulted in the specific detection of as few as 1-25 initial IS6110 targets in the five Mycobacterium complex species based on signal/noise criteria. Negative results were obtained with eight other Mycobacterium species as well as with 32 non-Mycobacterium species.
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PMID:Chemiluminescent detection of strand displacement amplified DNA from species comprising the Mycobacterium tuberculosis complex. 826 74

A polymerase chain reaction (PCR) assay for the rapid diagnosis of pulmonary tuberculosis was developed by using oligonucleotide primers to amplify a fragment of IS6110, an insertion sequence repeated multiple times in the chromosome of Mycobacterium tuberculosis. Sediment obtained from sputa processed by the N-acetyl-L-cysteine-NaOH method was suspended in a simple lysis buffer and was heated at 100 degrees C for 30 min prior to amplification. A dUTP-uracil N-glycosylase PCR protocol was used to prevent false-positive test results because of the carryover of products from previous amplification reactions. The 317-bp amplicon was detected by direct gel analysis and Southern blotting and then hybridization with a biotin-labeled internal probe. Hybrid molecules were detected by using a commercially available avidin-alkaline phosphatase-chemiluminescent substrate system (Tropix, Inc., Bedford, Mass.). The analytical sensitivity of the assay was 10 fg of purified mycobacterial DNA. The limits of detection by culture (Middlebrook 7H11 agar and Lowenstein-Jensen medium) and by PCR were equivalent in terminal dilution experiments for organism suspensions and positive sputa. An internal control was used to detect the presence of amplification inhibitors in each negative reaction mixture. DNA was purified from inhibitory specimens by phenol-chloroform extraction and ethanol precipitation. PCR results were compared with results of microscopy and conventional culture for the detection of M. tuberculosis in 313 sputum specimens. There were 124 specimens that were positive for M. tuberculosis by conventional methods and 113 (91%) that were positive by PCR. PCR detected 105 of 110 (95%) of the smear-positive and 8 of 14 (57%) of the smear-negative specimens. There were no false-positive results by PCR (specificity, 100%). This PCR assay innovations that make application of this new technology feasible in clinical microbiology laboratories.
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PMID:Direct detection of Mycobacterium tuberculosis in sputum by polymerase chain reaction and DNA hybridization. 834 53

The effect of a new zinc compound, beta-alanyl-L-histidinato zinc (AHZ), on osteopenia was investigated in rats with adjuvant arthritis. Arthritis was induced in female rats by administering 1% Mycobacterium butyricum (MB) into the subplantar surface of the right hind paw. AHZ (10, 30 and 100 mg/kg body weight) was orally administered to MB-treated rats 28 times at 24-h intervals, and the rats were bled 24 h after the last administration. Treatment with MB caused a remarkable increase in paw volume and a corresponding decrease in the ratio of albumin per globulin in serum, indicating that the treatment induces inflammation. These alterations were not significantly changed by the administration of AHZ (10, 30 and 100 mg/kg). Serum calcium and zinc concentrations are significantly decreased in rats with adjuvant arthritis. These decreases were completely restored by the administration of AHZ (30 and 100 mg/kg). Furthermore, the inflammation-induced decreases in alkaline phosphatase activity and calcium content in the femoral diaphysis were clearly blocked by the administration of AHZ (30 and 100 mg/kg). Also, the larger doses of AHZ (30 and 100 mg/kg) produced a significant increase in femoral-diaphyseal deoxyribonucleic acid and in the zinc content in rats with adjuvant arthritis. These results suggest that AHZ has a stimulating effect on bone formation in the femoral diaphysis of rats with adjuvant arthritis, although the compound did not have an anti-arthritic effect.
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PMID:Effect of beta-alanyl-L-histidinato zinc on bone metabolism in rats with adjuvant arthritis. 840 97

Detection of Mycobacterium tuberculosis in clinical specimens by the polymerase chain reaction (PCR) was compared with detection by culture. A 317-bp segment within the M. tuberculosis-specific insertion sequence IS6110 was amplified. The detection limit of the PCR assay for cultured mycobacteria was 50 cells per reaction by ethidium bromide-stained agarose gel electrophoresis and 5 cells per reaction by hybridization with an oligonucleotide probe conjugated with either digoxigenin or alkaline phosphatase (AP). This sensitivity was reduced fivefold in sputum specimens seeded with M. tuberculosis. Seventy-six clinical specimens were amplified and examined by the three detection methods. Both the digoxigenin and AP procedures were found to be more sensitive than agarose gel electrophoresis, but they were occasionally associated with a high background. An additional 308 specimens were examined only by agarose gel electrophoresis and the AP procedure. Of 71 specimens found to contain M. tuberculosis, amplified products were detected from 56 (79%) samples by agarose gel electrophoresis and/or the AP procedure. Of the additional 313 specimens that were culture negative for M. tuberculosis, 19 (6%) had amplified products detectable by agarose gel electrophoresis and/or the AP procedure. Compared with culture, PCR showed sensitivities and specificities of 55 and 98%, respectively, for agarose gel electrophoresis and 74 and 95%, respectively, for the AP procedure. Despite this low sensitivity, a rapid positive PCR result was accurate and clinically useful.
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PMID:Detection of Mycobacterium tuberculosis in clinical samples by two-step polymerase chain reaction and nonisotopic hybridization methods. 812 99

Patients infected with human immunodeficiency virus (HIV) are at risk for a variety of liver diseases. We undertook a retrospective study of 501 HIV-seropositive patients to assess the yield of percutaneous liver biopsy. The most common indications for liver biopsy were liver test abnormalities (89.5%), fever for 2 weeks (71.9%), and hepatomegaly (52.0%). The most common biopsy-derived diagnosis was Mycobacterium avium complex (MAC), seen in 87 (17.4%) biopsies. Mycobacterium tuberculosis was found in 13 biopsies (2.6%). In 28 biopsies (5.6%) mycobacteria was seen, but speciation of the organism was not possible. Chronic active viral hepatitis was seen in 60 biopsies (12.0%). Opportunistic hepatic infection from other organisms was found in 14 biopsies (2.8%). The most common neoplasm was lymphoma, which was seen in 12 biopsies (2.4%). MAC infection of the liver was associated with elevated alkaline phosphatase (p = 0.01). Among patients with fever for 2 weeks after an extensive negative workup including bone marrow biopsy, 58.2% had a diagnosis by liver biopsy. Overall, 64.3% of liver biopsies yielded a histopathological diagnosis, 45.7% of which were potentially treatable. We could not evaluate whether liver biopsy had a positive effect on patient outcome and survival, nor did we attempt to prove that liver biopsy resulted in a change in treatment or a change in preprocedure clinical diagnosis. Thus, questions about the efficacy of liver biopsy cannot be answered. Liver biopsy may be a helpful diagnostic tool in HIV-positive patients with fever, liver test abnormalities or hepatomegaly.
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PMID:Liver biopsy findings in 501 patients infected with human immunodeficiency virus (HIV). 855 99

The recognition of Mycobacterium leprae antigens by IgG subclasses in patients with leprosy was investigated by electrophoresing M. leprae sonicate in SDS-polyacrylamide gel and immunoblotting analysis. Serum pools were used from leprosy patients with either lepromatous (LL/BL) or tuberculoid (BT/TT) disease. A serum pool from healthy controls (EC) was used to determine the baseline antibody activity. To adjust for quantitative differences in antibodies across the disease spectrum, the LL/BL serum pool was used at a 1:200 dilution; the BT/TT serum pool, at 1:20 dilution. Monoclonal antibodies specific for each of the IgG subclasses were used as probes, with anti-mouse IgG conjugated to alkaline phosphatase as the revealing probe. IgG1 antibodies bound to several discrete bands in the range of 10-70 kDa in LL/BL patients, while BT/TT patients showed a more diffuse pattern with the strongest IgG1 antibody binding in the region of 25-40 kDa. Recognition with IgG2 was restricted to a region between 25-36 kDa (which also stained strongly for carbohydrates) in both LL/BL and BT/TT patients. Binding with IgG3 antibodies was more restricted than IgG1 antibodies in LL/BL sera with strong recognition restricted to 25 and 28 kDa. BT/TT sera showed strong binding with IgG3 antibodies in the region of 25-32 as well as 5-7 kDa. IgG4 antibodies showed weak binding to a 28-kDa in lepromatous patients only. The differences in IgG subclass recognition patterns and their implications are discussed.
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PMID:IgG subclass recognition pattern in leprosy: recognition of M. leprae antigens by IgG1 and IgG3 antibodies is distinct across the disease spectrum. 862 17


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