Bacterial Typing Techniques ; Mycobacterium tuberculosis ; classification ; genetics ; pathogenicity

This is a report on attempts tp search for a suitable experimental animal model which is sensitive to the exocellular substances of M. ulcerans, prior to study of biochemical and pathogenic natures of the substances. Cells of M. ulcerans grown in a broth medium were harvested by filtration and washed with phosphate-buffered saline. The filtrate of culture supernatant was subjected to fractionation by addition of various amounts of ammonium sulfate. The washed cells and the preparations resulted from ammonium sulfate fractionation (ASF 45 and ASF 70) were inoculated by either foot-pad injection, subcutaneous or intradermal injection to the selected animal groups. Any skin response due to administration of the preparations; erythema, edema, pus formation, etc. was macroscopically observed along with time progression. Among the animals employed, such as guinea pig, mouse, and rabbit, the rabbit was the only animal group showing strong skin response to the washed cells, ASF 45 and ASF 70. The heat-treated preparation of ASF 45 seemed to be inactive in elucidating skin response of rabbits. Dependence of skin response upon dose of the washed cells and the preparation of ASF 45 was also discussed.
Animal ; Erythema/etiology ; Guinea Pigs ; Intradermal Tests ; Mice ; Mycobacterium/pathogenicity* ; Rabbits

OBJECTIVETo explore the influences of Mycobacterium tuberculosis on the levels of human acute monocytic leukemia cell line THP-1 apoptosis and death.

METHODSHuman acute monocytic leukemia cell line THP-1 were infected with Mycobacterium tuberculosis strains H37Ra, H37Rv, or Beijing genotype (BJTB), respectively, to construct the infection models. Cell apoptosis was detected using flow cytometry. The distribution of the apoptotic proteins was detected using immunofluorescent staining assays. The cells late apoptosis was detected using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining assays. The change of cell death was determined by Tyrpan blue staining assays.

RESULTSTHP-1 apoptosis was induced by Mycobacterium tuberculosis strains H37Ra, H37Rv, and BJTB. H37Ra strongly induced THP-1 apoptosis, H37Rv weakly induced THP-1 apoptosis, and BJTB induced THP-1 apoptosis at the lowest level among these three Mycobacterium tuberculosis strains. On the contrary, BJTB strongly induced THP-1 death, H37Rv weakly induced THP-1 death, and H37Ra induced THP-1 death at the lowest level.

CONCLUSIONSMycobacterial strains with different virulence induce different levels of apoptosis and death of THP-1 cells. Compared with highly virulent strains, attenuated strains induce more apoptosis and less death.

Apoptosis ; Cell Line, Tumor ; Humans ; In Situ Nick-End Labeling ; Leukemia, Monocytic, Acute ; Mycobacterium tuberculosis ; pathogenicity ; Virulence

BACKGROUNDMycobacterial interspersed repetitive units-variable number tandem repeat (MIRU-VNTR) and Beijing family typing based on detecting the deletion of RD105 sequence are two common genotyping methods used to study the molecular epidemiologic characteristics of Mycobacterium (M.) tuberculosis. We collected 218 strains of M. tuberculosis between 2004 and 2006 in the Linxia Hui Autonomous Prefecture of Gansu province in Northwest China.

METHODSMIRU-VNTR analysis and Beijing family typing based on detecting the deletion of RD105 sequence were used to type the 218 strains, and their typing power was evaluated to look for practical and efficient genotyping methods suitable for the region.

RESULTSThe MIRU typing yielded 115 distinct genotypes, including 98 unique isolates and 17 different clusters containing 120 isolates (55.05%); the cluster rate was 47.25%. By detecting the deletion of RD105 sequence, 188 of 218 (86.23%) isolates belonged to Beijing family. Combination of Beijing family typing and MIRU typing yielded 118 distinct patterns, including 101 unique isolates and 17 clusters containing 117 isolates (54.13%). The largest cluster contained 58 strains with MIRU genotype of 223325173533 which contained 50 strains belonging to Beijing family and 8 strains belonging to non-Beijing family.

CONCLUSIONSThe Beijing family strains occupied a large proportion and the Beijing family MIRU genotype 223325173533 is a dominant strain in Linxia of Gansu. Combining detecting the deletion of RD105 and MIRU typing together provides a simple, fast, and effective method which is low in cost and might be practical and suitable for M. tuberculosis genotyping in China.

Alleles ; China ; epidemiology ; Genotype ; Molecular Epidemiology ; Multiplex Polymerase Chain Reaction ; Mycobacterium tuberculosis ; genetics ; pathogenicity ; Tuberculosis ; epidemiology

Along with the rapid spread of HIV / AIDS and TB prevalence, prevention and control of AIDS and tuberculosis has become an urgent problem in the field of public health. Recent studies demonstrate dual infections of HIV and TB are not a simple superposition of two diseases, but a course of mutual promotion. This article has summarized the pathological mechanisms and mutual interactions of HIV/TB dual infections.
Acquired Immunodeficiency Syndrome ; complications ; epidemiology ; prevention & control ; Coinfection ; HIV-1 ; pathogenicity ; Humans ; Mycobacterium tuberculosis ; pathogenicity ; Prevalence ; Public Health ; Tuberculosis ; complications ; epidemiology ; prevention & control

Acid-fast microorganisms were isolated from 240 soil samples collected at two areas, Hiroshima, Japan and Seoul, Korea. The biological and biochemical characteristics of the isolated mycobacteria were tested and compared with those of 36 reference mycobacteria Strains. The isolation rate and distribution of these mycobacterial species from soil were compared using three kinds of media with emphasis on the two methods of isolation between the different geographical areas. One Strain from each of the 10 species among atypical mycobacteria isolated from soil in both areas was inoculated into ddY mice and the pathogenicity compared with that of Mycobacterium tuberculosis H37Rv up to 6 weeks. Susceptibility of the reisolated acid-fast bacilli to antimycobacterial agents was tested in vitro. Antibody responses against various mycobacterial antigens were tested using lepromatous type and tuberculoid type patient sera by the agar gel immunodiffusion. 1) No significant differences in the distribution of acid-fast bacilli were observed between soil samples from the two regions. 2) Rapid growers were by far the most frequent acid-fast bacilli isolated while no photochromogens were isolated from these soil samples. In addition, a minimal number of fastidious mycobacteria were isolated but not cultivable in subcultures. 3) Some of these soil acid-fast bacilli were capable of inducing only transient bacteriological and pathologic changes in mouse organs. 4) Acid-fast bacilli reisolated from organs of these infected mice were, in general, found to be resistant to antimycobacterial agents. 5) M. scrofulaceum antigen showed a precipitation reaction in agar gel immunodiffusion with the highest number of sera from leprosy patients.
Animal ; Leprosy/immunology ; Mice ; Mycobacteria, Atypical/drug effects ; Mycobacteria, Atypical/isolation & purification* ; Mycobacteria, Atypical/pathogenicity ; Mycobacterium/isolation & purification* ; Mycobacterium Infections/pathology ; Soil Microbiology*

Animals ; Disease Models, Animal ; Embryo, Nonmammalian ; microbiology ; Host-Parasite Interactions ; Mycobacterium Infections, Nontuberculous ; immunology ; microbiology ; Mycobacterium marinum ; pathogenicity ; Tuberculoma ; immunology ; microbiology ; Zebrafish ; embryology ; microbiology

BACKGROUNDGene chip array can differentiate isolated mycobacterial strains using various mycobacterium specific probes simultaneously. Gene chip array can evaluate drug resistance to isoniazid and rifampin of tuberculosis strains by detecting drug resistance related gene mutation. This technique has great potential for clinical application. We performed a retrospective study to investigate the capability of gene chip array in the rapid differentiation of species and detection of drug resistance in mycobacterium, and to evaluate its clinical efficacy.

METHODSWe selected 39 patients (54 clinical mycobacterium isolates), used gene chip array to identify the species of these isolates and detect drug resistance to isoniazid and rifampin in Mycobacterium tuberculosis isolates. Meanwhile, these patients' clinical data were analyzed retrospectively.

RESULTSAmong these 39 patients whose mycobacterium culture were positive, 32 patients' isolates were identified as Mycobacterium tuberculosis, all of them were clinical infection. Seven patients' isolates were identified as non-tuberculosis mycobacterium. Analyzed with their clinical data, only two patients were considered as clinical infection, both of them were diagnosed as hematogenous disseminated Mycobacterium introcellulare infection. The other five patients' isolates were of no clinical significance; their clinical samples were all respiratory specimens. Clinical manifestations of tuberculosis and non-tuberculous mycobacterial infections were similar. Isoniazid resistance was detected in two tuberculosis patients, while rifampin resistance was detected in one tuberculosis patient; there was another patient whose Mycobacterium tuberculosis isolate was resistant to both isoniazid and rifampin (belongs to multidrug resistance tuberculosis). The fact that this patient did not respond to routine anti-tuberculosis chemotherapy also confirmed this result.

CONCLUSIONSGene chip array may be a simple, rapid, and reliable method for the identification of most mycobacterial species and detection of drug resistance in Mycobacterium tuberculosis. It is useful in diagnosis, treatment, and hospital infection control of mycobacterial infections, and it may have a great potential for clinical application.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antitubercular Agents ; therapeutic use ; Female ; Humans ; Isoniazid ; therapeutic use ; Male ; Middle Aged ; Mycobacterium ; classification ; genetics ; pathogenicity ; Mycobacterium tuberculosis ; genetics ; pathogenicity ; Oligonucleotide Array Sequence Analysis ; methods ; Rifampin ; therapeutic use ; Tuberculosis, Multidrug-Resistant ; genetics ; Young Adult

OBJECTIVEThis study aimed to review the available literatures on control of latent tuberculosis (TB) infection and propose a new control strategy to shorten the course of TB chemotherapy.

DATA SOURCESThe data used in this review were mainly obtained from articles listed in PubMed. The search terms were "therapy (treatment) of tuberculosis," "therapy (treatment) of latent TB infection," and "vaccine of TB."

STUDY SELECTIONArticles regarding treatment and vaccine of TB were selected and reviewed.

RESULTSThe most crucial reason causing the prolonged course of TB chemotherapy is the dormant state of Mycobacterium tuberculosis (M. tuberculosis). Nevertheless, there are, to date, no effective drugs that can directly kill the dormant cells of M. tuberculosis in clinical therapy. In accordance with the growth cycle of dormant M. tuberculosis in the body, the methods for controlling dormant M. tuberculosis include direct killing with drugs, prevention of dormant M. tuberculosis resuscitation with vaccines, and resuscitating dormant M. tuberculosis with preparations or drugs and then thoroughly killing these resuscitated M. tuberculosis by using anti-TB therapy.

CONCLUSIONSThe comprehensive analysis of the above three methods suggests that the drugs directly killing dormant cells are in clinical trials, TMC207 is the most beneficial for controlling TB. Because the side effect of vaccines is less and their action period is long, prevention of dormant cells resuscitation with vaccines is promising. The last control method makes it probable that when a huge number of active cells of M. tuberculosis have been killed and eradicated after 1-month short chemotherapy, only a strong short-term subsequent chemotherapy can completely kill and eradicate the remaining M. tuberculosis. This control strategy is expected to significantly shorten the course of TB chemotherapy and bring a new change and breakthrough in TB treatment.

Antitubercular Agents ; therapeutic use ; Diarylquinolines ; therapeutic use ; Humans ; Latent Tuberculosis ; drug therapy ; Mycobacterium tuberculosis ; pathogenicity ; Tuberculosis ; drug therapy

Expression microarray was employed in this study to investigate whether the ion channels and their regulatory elements encoding genes participate in the immune response to Mycobacterium tuberculosis infection. The results of a virulent strain were compared with those of the clinically isolated strains. The data demonstrate that K(+), Na(+), Ca(2+) and Cl(-) channels and their regulatory elements, such as the G protein, receptor and second messenger, protein kinase and protein phosphatase were involved in the immune reaction. The clinical strain affected more types of ion channels and respective regulatory elements. The data provides clues for further scrutiny into the role of ion channels and related elements in the interaction between Mycobacterium tuberculosis and host macrophage.
Gene Expression Regulation ; Humans ; Ion Channels ; genetics ; Macrophages ; immunology ; microbiology ; Mycobacterium tuberculosis ; pathogenicity ; Regulatory Elements, Transcriptional ; Tuberculosis ; genetics ; immunology ; microbiology