WorldWideScience
 
 
1

Análise de restrição enzimática do gene hsp65 de isolados clínicos de pacientes com suspeita de tuberculose pulmonar em Teresina, Piauí / Restriction enzyme analysis of the hsp65 gene in clinical isolates from patients suspected of having pulmonary tuberculosis in Teresina, Brazil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Identificar as espécies de micobactérias encontradas no escarro de pacientes com suspeita de tuberculose pulmonar e analisar o impacto dessas identificações na abordagem terapêutica. MÉTODOS: Foram avaliados 106 pacientes com suspeita de tuberculose pulmonar encaminhados para o serviço de [...] pneumologia de um hospital público em Teresina, Piauí. Espécimes de escarro matinal foram avaliados quanto à presença de micobactérias por baciloscopia e cultura. Foram utilizadas PCR e análise de restrição enzimática do gene hsp65 (PRA-hsp65) para a identificação das cepas de micobactérias isoladas em cultura. RESULTADOS: Foram analisadas 206 amostras de escarro. A idade dos pacientes variou de 15 a 87 anos, sendo 67% do gênero masculino. Tosse ocorreu em 100% dos casos. O padrão radiográfico predominante foi de lesão moderada, observada em 70%. A positividade no esfregaço foi de 76%, e isolamento em cultura ocorreu em 91% das culturas executadas. Testes tradicionais identificaram micobactérias não tuberculosas (MNT) em 9% dos isolados. O método PRA-hsp65 confirmou esses dados, mostrando sete padrões de bandas capazes de identificar as espécies de MNT isoladas: Mycobacterium kansasii; M. abscessus 1; M. abscessus 2; M. smegmatis; M. flavescens 1; M. gordonae 5 e M. gordonae 7. Todos os pacientes com MNT tinham mais de 60 anos, e observaram-se bronquiectasias em 88% das radiografias. Houve dois casos de reinfecção, identificados inicialmente como infecção por M. abscessus e M. kansasii. CONCLUSÕES: As MNT causam infecção pulmonar em pacientes imunocompetentes, e a identificação das MNT é importante para estabelecer o diagnóstico correto e a decisão terapêutica mais adequada. O método PRA-hsp65 é útil para identificar espécies de MNT e pode ser implantado em laboratórios de biologia molecular não especializados em micobactérias. Abstract in english OBJECTIVE: To identify mycobacterial species in the sputum of patients suspected of having pulmonary tuberculosis and to determine the impact that the acquisition of this knowledge has on the therapeutic approach. METHODS: We evaluated 106 patients suspected of having pulmonary tuberculosis and refe [...] rred to the pulmonology department of a public hospital in the city of Teresina, Brazil. Morning sputum specimens were evaluated for the presence of mycobacteria by sputum smear microscopy and culture. We used PCR and restriction enzyme analysis of the hsp65 gene (PRA-hsp65) to identify the strains of mycobacteria isolated in culture. RESULTS: A total of 206 sputum samples were analyzed. Patient ages ranged from 15 to 87 years, and 67% were male. There was cough in 100% of the cases. The predominant radiographic pattern was moderate disease, observed in 70%. Smear positivity was 76%, and isolation in culture occurred in 91% of the cultures. Traditional tests identified nontuberculous mycobacteria (NTM) in 9% of the isolates. The PRA-hsp65 method confirmed these data, showing seven band patterns that were able to identify the isolated species of NTM: Mycobacterium kansasii; M. abscessus 1; M. abscessus 2; M. smegmatis; M. flavescens 1; M. gordonae 5; and M. gordonae 7. All of the patients with NTM were over 60 years of age, and bronchiectasis was seen in 88% of the X-rays. There were two cases of reinfection, initially attributed to M. abscessus and M. kansasii. CONCLUSIONS: In immunocompetent patients, NTM can infect the lungs. It is important to identify the specific NTM in order to establish the correct diagnosis and choose the most appropriate therapeutic regimen. The PRA-hsp65 method is useful in identifying NTM species and can be implemented in molecular biology laboratories that do not specialize in the identification of mycobacteria.

Maria das Graças Motta e, Bona; Maria José Soares, Leal; Liline Maria Soares, Martins; Raimundo Nonato da, Silva; José Adail Fonseca de, Castro; Semiramis Jamil Hadad do, Monte.

2

Análise de restrição enzimática do gene hsp65 de isolados clínicos de pacientes com suspeita de tuberculose pulmonar em Teresina, Piauí / Restriction enzyme analysis of the hsp65 gene in clinical isolates from patients suspected of having pulmonary tuberculosis in Teresina, Brazil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Identificar as espécies de micobactérias encontradas no escarro de pacientes com suspeita de tuberculose pulmonar e analisar o impacto dessas identificações na abordagem terapêutica. MÉTODOS: Foram avaliados 106 pacientes com suspeita de tuberculose pulmonar encaminhados para o serviço de [...] pneumologia de um hospital público em Teresina, Piauí. Espécimes de escarro matinal foram avaliados quanto à presença de micobactérias por baciloscopia e cultura. Foram utilizadas PCR e análise de restrição enzimática do gene hsp65 (PRA-hsp65) para a identificação das cepas de micobactérias isoladas em cultura. RESULTADOS: Foram analisadas 206 amostras de escarro. A idade dos pacientes variou de 15 a 87 anos, sendo 67% do gênero masculino. Tosse ocorreu em 100% dos casos. O padrão radiográfico predominante foi de lesão moderada, observada em 70%. A positividade no esfregaço foi de 76%, e isolamento em cultura ocorreu em 91% das culturas executadas. Testes tradicionais identificaram micobactérias não tuberculosas (MNT) em 9% dos isolados. O método PRA-hsp65 confirmou esses dados, mostrando sete padrões de bandas capazes de identificar as espécies de MNT isoladas: Mycobacterium kansasii; M. abscessus 1; M. abscessus 2; M. smegmatis; M. flavescens 1; M. gordonae 5 e M. gordonae 7. Todos os pacientes com MNT tinham mais de 60 anos, e observaram-se bronquiectasias em 88% das radiografias. Houve dois casos de reinfecção, identificados inicialmente como infecção por M. abscessus e M. kansasii. CONCLUSÕES: As MNT causam infecção pulmonar em pacientes imunocompetentes, e a identificação das MNT é importante para estabelecer o diagnóstico correto e a decisão terapêutica mais adequada. O método PRA-hsp65 é útil para identificar espécies de MNT e pode ser implantado em laboratórios de biologia molecular não especializados em micobactérias. Abstract in english OBJECTIVE: To identify mycobacterial species in the sputum of patients suspected of having pulmonary tuberculosis and to determine the impact that the acquisition of this knowledge has on the therapeutic approach. METHODS: We evaluated 106 patients suspected of having pulmonary tuberculosis and refe [...] rred to the pulmonology department of a public hospital in the city of Teresina, Brazil. Morning sputum specimens were evaluated for the presence of mycobacteria by sputum smear microscopy and culture. We used PCR and restriction enzyme analysis of the hsp65 gene (PRA-hsp65) to identify the strains of mycobacteria isolated in culture. RESULTS: A total of 206 sputum samples were analyzed. Patient ages ranged from 15 to 87 years, and 67% were male. There was cough in 100% of the cases. The predominant radiographic pattern was moderate disease, observed in 70%. Smear positivity was 76%, and isolation in culture occurred in 91% of the cultures. Traditional tests identified nontuberculous mycobacteria (NTM) in 9% of the isolates. The PRA-hsp65 method confirmed these data, showing seven band patterns that were able to identify the isolated species of NTM: Mycobacterium kansasii; M. abscessus 1; M. abscessus 2; M. smegmatis; M. flavescens 1; M. gordonae 5; and M. gordonae 7. All of the patients with NTM were over 60 years of age, and bronchiectasis was seen in 88% of the X-rays. There were two cases of reinfection, initially attributed to M. abscessus and M. kansasii. CONCLUSIONS: In immunocompetent patients, NTM can infect the lungs. It is important to identify the specific NTM in order to establish the correct diagnosis and choose the most appropriate therapeutic regimen. The PRA-hsp65 method is useful in identifying NTM species and can be implemented in molecular biology laboratories that do not specialize in the identification of mycobacteria.

Maria das Graças Motta e, Bona; Maria José Soares, Leal; Liline Maria Soares, Martins; Raimundo Nonato da, Silva; José Adail Fonseca de, Castro; Semiramis Jamil Hadad do, Monte.

2011-10-01

3

First report of disseminated Mycobacterium skin infections in two liver transplant recipients and rapid diagnosis by hsp65 gene sequencing  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We present here the first report of disseminated skin Mycobacterium infections in two liver transplant recipients, in which hsp65 gene sequencing was used for rapid species identification. Both patients had hepatitis B virus-related cirrhosis and diabetes mellitus and presented with progressive generalized, nodular skin lesions. In one patient, a 50-year-old woman who had frequent contact with marine fish, an acid-fast bacillus was isolated from skin biopsy tissue after 2 months of culture. W...

Lau, Susanna K. P.; Curreem, Shirly O. T.; Ngan, Antonio H. Y.; Yeung, Chi-keung; Yuen, Kwok-yung; Woo, Patrick C. Y.

2011-01-01

4

Combined rpoB duplex PCR and hsp65 PCR restriction fragment length polymorphism with capillary electrophoresis as an effective algorithm for identification of Mycobacterial species from clinical isolates  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Mycobacteria can be quickly and simply identified by PCR restriction-enzyme analysis (PRA, but misidentification can occur because of similarities in band sizes that are critical for discriminating among species. Capillary electrophoresis can provide computer-aided band discrimination. The aim of this research was to develop an algorithm for identifying mycobacteria by combined rpoB duplex PRA (DPRA and hsp65 PRA with capillary electrophoresis. Results Three hundred and seventy-six acid-fast bacillus smear-positive BACTEC cultures, including 200 Mycobacterium tuberculosis complexes (MTC and 176 non-tuberculous mycobacteria (NTM were analyzed. With combined hsp65 and rpoB DPRA, the accuracy rate was 100% (200 isolates for the MTC and 91.4% (161 isolates for the NTM. Among the discordant results (8.6% for the NTM, one isolate of Mycobacterial species and an isolate of M. flavescens were found as new sub-types in hsp65 PRA. Conclusions This effective and novel identification algorithm using combined rpoB DPRA and hsp65 PRA with capillary electrophoresis can rapidly identify mycobacteria and find new sub-types in hsp65 PRA. In addition, it is complementary to 16 S rDNA sequencing.

Huang Chen-Cheng

2012-07-01

5

Ten tandem repeats of ?-hCG 109-118 enhance immunogenicity and anti-tumor effects of ?-hCG C-terminal peptide carried by mycobacterial heat-shock protein HSP65  

International Nuclear Information System (INIS)

The ?-subunit of human chorionic gonadotropin (?-hCG) is secreted by many kinds of tumors and it has been used as an ideal target antigen to develop vaccines against tumors. In view of the low immunogenicity of this self-peptide,we designed a method based on isocaudamer technique to repeat tandemly the 10-residue sequence X of ?-hCG (109-118), then 10 tandemly repeated copies of the 10-residue sequence combined with ?-hCG C-terminal 37 peptides were fused to mycobacterial heat-shock protein 65 to construct a fusion protein HSP65-X10-?hCGCTP37 as an immunogen. In this study, we examined the effect of the tandem repeats of this 10-residue sequence in eliciting an immune by comparing the immunogenicity and anti-tumor effects of the two immunogens, HSP65-X10-?hCGCTP37 and HSP65-?hCGCTP37 (without the 10 tandem repeats). Immunization of mice with the fusion protein HSP65-X10-?hCGCTP37 elicited much higher levels of specific anti-?-hCG antibodies and more effectively inhibited the growth of Lewis lung carcinoma (LLC) in vivo than with HSP65-?hCGCTP37, which should suggest that HSP65-X10-?hCGCTP37 may be an effective protein vaccine for the treatment of ?-hCG-dependent tumors and multiple tandem repeats of a certain epitope are an efficient method to overcome the low immunogenicity of self-peptide antigens

6

Identification of nontuberculous mycobacteria isolated from Hanwoo (Bos taurus coreanae) in South Korea by sequencing analysis targeting hsp65, rpoB and 16S rRNA genes.  

Science.gov (United States)

Combinatorial molecular taxonomic approaches targeting 3 genes, 16S rRNA (1.2-1.3kbp), hsp65 (603-bp), and rpoB genes (711-bp) were applied to 43 non-tuberculous mycobacteria (NTM) strains isolated from a Korean native cattle from bronchial lymph nodes and lung, Hanwoo (Bos taurus coreanae) in South Korea. Of 43 NTM isolates, Mycobacterium avium complex strains (MAC) were isolated with the highest frequency (31 strains, 72.1%). Contrary to other reports, M. intracellulare strains (23 strains, 53.5%) of MACs were more prevalent than M. avium strains (8 strains, 18.6%). Further separation of isolated M. intracellulare into genotype level by hsp65 analysis showed that isolates of the HG-1 genotype (60.9%, 14/23 isolates), known to be specific to Korean patients, was more prevalent than the HG-2 type (17.4%, 4/23 strains), which include the type strain, M. intracellulare ATCC 13950(T). Compared to NTM infections of Korean human patients, the pronounced difference found in this study is that no M. abscessus infections in Hanwoo were found. In conclusion, our data showed that the isolated species frequency of NTMs, particularly MACs from Hanwoo, was very comparable to that obtained from Korean human infection, suggesting that humans and Korean native cattle may share common environmental sources for NTM infections. PMID:25171916

Kim, Bo-Ram; Kim, Jae Myung; Kim, Byoung-Jun; Jang, Yunho; Ryoo, Soyoon; Kook, Yoon-Hoh; Kim, Bum-Joon

2014-10-10

7

DETECÇÃO DO COMPLEXO Mycobacterium tuberculosis NO LEITE PELA REAÇÃO EM CADEIA DA POLIMERASE SEGUIDA DE ANÁLISE DE RESTRIÇÃO DO FRAGMENTO AMPLIFICADO (PRA DETECTION OF Mycobacterium tuberculosis COMPLEX BY PCR-RESTRICTION FRAGMENT LENGTH POLYMORFISM ANALYSIS OF THE HSP65 GENE  

Directory of Open Access Journals (Sweden)

Full Text Available Mycobacterium bovis é membro do complexo Mycobacterium tuberculosis (MTBC, grupo este composto por espécies com grande homologia genética. É o agente etiológico da tuberculose bovina, importante zoonose transmissível ao homem, principalmente através da inalação do bacilo e/ou pelo consumo de leite e derivados não-pasteurizados provenientes de vacas tuberculosas. O objetivo deste estudo foi padronizar a identificação de micobactérias do complexo M. tuberculosis presentes no leite, por metodologia molecular. Fez-se a extração de DNA diretamente do leite contaminado e realizou-se a identificação molecular pela reação em cadeia da polimerase seguida de análise de restrição do fragmento amplificado (PRA. Utilizaram-se inhagens de referência e leite cru artificialmente contaminado com M. bovis IP. Um fragmento de 441pb do gene hsp65 foi amplificado, tratado com BstEII e HaeIII e empregou-se o perfil de restrição enzimática obtido para identificar o complexo M. tuberculosis no leite. Com a PRA foi possível detectar com especificidade e sensibilidade a presença de M. bovis em até 10 UFC/mL de leite. A metodologia padronizada poderá auxiliar os métodos microbiológicos e bioquímicos tradicionalmente usados na identificação do bacilo em alimentos suspeitos de contaminação, como, por exemplo, o leite proveniente de animais suspeitos de infecção por M. bovis.

Palavras-chaves: Análise de perfil de restrição enzimática (PRA, complexo Mycobacterium tuberculosis, leite, Mycobacterium bovis, limite de detecção (PCR. Mycobacterium bovis is a member of the M. tuberculosis complex, a group composed by species with high genetic homology. The pathogen is the etiological agent of bovine tuberculosis, an important zoonosis that is mainly transmitted by inhalation of infectious droplet nuclei or by ingestion of milk and crude milk derivative products from tuberculosis cows. The definitive identification of M. bovis, up to species level, is time consuming and difficult. In this work, the objective was to standardize a polymerase chain reaction followed by an enzyme restriction analysis in order to identify the M. tuberculosis complex in milk, without a microbiological isolation step. Reference strains and raw milk seeded with M. Bovis, were used as the starting material.  A 441pb fragment of the hsp65 gene was amplified and digested by two restriction enzymes BstEII and HaeIII. The obtained profile was used to identify the M. tuberculosis complex in milk. The minimum limit of detection of M. bovis in milk was 10CFU/mL. PRA methodology proved to be a specific and sensible method. It can be used to assist the microbiological and biochemical methods commonly used to identifying the bacilli in clinical samples, as milk 

Key word: Detection limit (PRA, Mycobacterium tuberculosis complex, milk Mycobacterium bovis, Restriction Enzyme Analysis (PCR,

Joab Trajano Silva

2008-12-01

8

Th1 polarized response induced by intramuscular DNA-HSP65 immunization is preserved in experimental atherosclerosis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english We previously reported that a DNA vaccine constructed with the heat shock protein (HSP65) gene from Mycobacterium leprae (DNA-HSP65) was protective and also therapeutic in experimental tuberculosis. By the intramuscular route, this vaccine elicited a predominant Th1 response that was consistent with [...] its protective efficacy against tuberculosis. It has been suggested that the immune response to Hsp60/65 may be the link between exposure to microorganisms and increased cardiovascular risk. Additionally, the high cholesterol levels found in atherosclerosis could modulate host immunity. In this context, we evaluated if an atherogenic diet could modulate the immune response induced by the DNA-HSP65 vaccine. C57BL/6 mice (4-6 animals per group) were initially submitted to a protocol of atherosclerosis induction and then immunized by the intramuscular or intradermal route with 4 doses of 100 µg DNA-HSP65. On day 150 (15 days after the last immunization), the animals were sacrificed and antibodies and cytokines were determined. Vaccination by the intramuscular route induced high levels of anti-Hsp65 IgG2a antibodies, but not anti-Hsp65 IgG1 antibodies and a significant production of IL-6, IFN-g and IL-10, but not IL-5, indicating a Th1 profile. Immunization by the intradermal route triggered a mixed pattern (Th1/Th2) characterized by synthesis of anti-Hsp65 IgG2a and IgG1 antibodies and production of high levels of IL-5, IL-6, IL-10, and IFN-g. These results indicate that experimentally induced atherosclerosis did not affect the ability of DNA-HSP65 to induce a predominant Th1 response that is potentially protective against tuberculosis.

D.M., Fonseca; V.L.D., Bonato; C.L., Silva; A., Sartori.

9

Recurrent nontuberculous mycobacterial endophthalmitis: a diagnostic conundrum  

Directory of Open Access Journals (Sweden)

Full Text Available Nandini Venkateswaran,1 Gabrielle Yeaney,2 Mina Chung,3,4 Holly B Hindman3,41University of Rochester School of Medicine and Dentistry, University of Rochester, 2Department of Pathology and Laboratory Medicine, 3Flaum Eye Institute, 4Center for Visual Science, University of Rochester School of Medicine and Dentistry, Rochester, NY, USAObjective: To report a case of recurrent nontuberculous mycobacterial endophthalmitis in the context of neurotrophic keratopathy secondary to herpes zoster ophthalmicus that had an atypical presentation and complex course, and highlights the challenges of causative organism identification and therapeutic interventions in this condition.Methods: A retrospective chart review was conducted to determine the visual outcomes of the patient.Results: A 68-year-old pseudophakic male with long-standing neurotrophic keratopathy and perforated descemetocele managed with cyanoacrylate glue and a contact bandage lens in the left eye, began experiencing recurrent episodes of endophthalmitis after undergoing a penetrating keratoplasty. Several therapeutic procedures including an anterior chamber washout, two pars plana vitrectomies, explantation of the posterior chamber intraocular lens and capsular bag, and multiple intravitreal antimicrobial injections, were performed to which he has ultimately responded favorably, with no signs of infection to date and stable visual acuity. The causative organism of his recurrent infections was initially identified as Mycobacterium abscessus through biochemical testing and 16S ribosomal ribonucleic acid gene sequencing; however, repeat polymerase chain reaction (PCR and sequencing of the 65 kDa heat shock protein (hsp65 gene for experimental purposes confirmed the accurate identification of the organism to be Mycobacterium chelonae. Given the greater reliability of PCR and sequencing of the hsp65 gene over traditional biochemical tests and culture techniques, M. chelonae was likely the infectious agent all along, and the organism was originally misidentified on the basis of less accurate tests.Conclusion: Recurrent atypical mycobacterial endophthalmitis requires expedient identification and management to prevent poor visual outcomes. Standard biochemical testing can identify the causative organism but is limited by the inability to distinguish between nontuberculous species reliably. We recommend the use of PCR in conjunction with sequencing of the hsp65 gene for reliable differentiation of M. chelonae and M. abscessus in atypical mycobacterial ocular infections. Minimum inhibitory concentration antibiotic susceptibility tests on cultured strains are the best guide to antibiotic selection, given the rapidly rising resistance to antimicrobials in atypical mycobacterial species.Keywords: atypical mycobacteria, herpes zoster ophthalmicus, hsp65, Mycobacterium chelonae, neurotrophic keratopathy, visual outcome

Venkateswaran N

2014-05-01

10

Tissue distribution of DNA-Hsp65/TDM-loaded PLGA microspheres and uptake by phagocytic cells  

Science.gov (United States)

This study aimed to demonstrate that microspheres, used as delivery vehicle of DNA-Hsp65/TDM [plasmid DNA encoding heat shock protein 65 (Hsp65) coencapsulated with trehalose dimycolate (TDM) into PLGA microspheres], are widely spread among several organs after intramuscular administration in BALB/c mice. In general, we showed that these particles were phagocytosed by antigen presenting cells, such as macrophages and dendritic cells. Besides, it was demonstrated herein that draining lymph node cells presented a significant increase in the number of cells expressing costimulatory molecules (CD80 and CD86) and MHC class II, and also that the administration of the DNA-Hsp65/TDM and vector/TDM formulations resulted in the up-regulation of CD80, CD86 and MHC class II expression when compared to control formulations (vector/TDM and empty). Regarding the intracellular trafficking we observed that following phagocytosis, the microspheres were not found in the late endosomes and/or lysosomes, until 15 days after internalization, and we suggest that these constructions were hydrolysed in early compartments. Overall, these data expand our knowledge on PLGA [poly (lactic-co- glycolic acid)] microspheres as gene carriers in vaccination strategies, as well as open perspectives for their potential use in clinical practice. PMID:17880727

Trombone, Ana Paula F; Silva, Celio L; Almeida, Luciana P; Rosada, Rogerio S; Lima, Karla M; Oliver, Constance; Jamur, Maria C; Coelho-Castelo, Arlete AM

2007-01-01

11

Influência do biofármaco DNA-hsp65 na lesão pulmonar induzida por bleomicina Influence of a DNA-hsp65 vaccine on bleomycin-induced lung injury  

Directory of Open Access Journals (Sweden)

Full Text Available OBJETIVO: Avaliar a influência do biofármaco DNA-hsp65 em um modelo de distúrbio fibrosante pulmonar experimental. MÉTODOS: Foram estudados 120 camundongos machos C57BL/6, divididos em quatro grupos: grupo SS, animais tratados com salina (placebo e injetados com salina intratraqueal (IT; grupo SB, tratados com salina (placebo e injetados com bleomicina IT; grupo PB, tratados com plasmídeo, sem gene bacteriano, e injetados com bleomicina IT; e grupo BB, tratados com DNA-hsp65 e injetados com bleomicina IT. A bleomicina foi injetada 15 dias após a última imunização, e os animais sacrificados seis semanas após o uso da droga IT. O pulmão esquerdo retirado foi utilizado para análise morfológica, e o pulmão direito para dosagens de hidroxiprolina. RESULTADOS: A proporção de camundongos que apresentaram morte não-programada depois de 48 h da injeção IT foi maior no grupo SB em comparação ao grupo SS (57,7% vs. 11,1%. A área percentual média de interstício septal foi maior nos grupos SB e PB (53,1 ± 8,6% e 53,6 ± 9,3%, respectivamente em comparação aos grupos SS e BB (32,9 ± 2,7% e 34,3 ± 6,1%, respectivamente. Os grupos SB, PB e BB mostraram aumentos nos valores médios da área de interstício septal corada por picrosirius em comparação ao grupo SS (SS: 2,0 ± 1,4%; SB: 8,2 ± 4,9%; PB: 7,2 ± 4,2%; e BB:6,6±4,1%.O conteúdo pulmonar de hidroxiprolina no grupo SS foi inferior ao dos demais grupos (SS: 104,9 ± 20,9 pg/pulmão; SB: 160,4 ±47,8 pg/pulmão; PB:170,0 ± 72,0 pg/pulmão; e BB: 162,5 ± 39,7 pg/pulmão. CONCLUSÕES: A imunização com o biofármaco DNA-hsp65 interferiu na deposição de matriz não-colágena em um modelo de lesão pulmonar induzida por bleomicina.OBJECTIVE: To evaluate the effects of immunization with a DNA-hsp65 vaccine in an experimental model of pulmonary fibrosis. METHODS: A total of 120 male C57BL/6 mice were distributed into four groups: SS, injected with saline (placebo and then receiving intratracheal (IT instillation of saline; SB, injected with saline (placebo and then receiving IT instillation of bleomycin; PB, treated with plasmid only, without bacterial genome, and then receiving IT instillation of bleomycin; and BB, treated with the vaccine and then receiving IT instillation of bleomycin. Bleomycin was instilled 15 days after the last immunization, and the animals were killed six weeks thereafter. The left and right lungs were removed, the former for morphological analysis and the latter for hydroxyproline measurements. RESULTS: The proportion of deaths within the first 48 h after the IT instillation (deaths attributed to the surgical procedure was higher in the SB group than in the SS group (57.7% vs. 11.1%. The mean area of pulmonary interstitial septa was greater in the SB and PB groups (53.1 ± 8.6% and 53.6±9.3%, respectively than in the SS and BB groups (32.9 ± 2.7% and 34.3 ± 6.1%, respectively. The mean area of interstitial septa stained by picrosirius was greater in the SB, PB and BB groups than in the SS group (8.2 ± 4.9%, 7.2 ± 4.2% and 6.6 ± 4.1%, respectively, vs. 2.0±1.4%. The total hydroxyproline content in the lung was significantly lower in the SS group (104.9 ± 20.9 pg/lung than in the other groups (SB: 160.4 ± 47.8 pg/lung; PB: 170.0 ± 72.0 pg/lung; and BB: 162.5 ± 39.7 pg/lung. CONCLUSIONS: Immunization with the DNA-hsp65 vaccine reduced the deposition of noncollagen matrix in a model of bleomycin-induced lung lesion.

Adriana Ignacio de Padua

2008-11-01

12

Influência do biofármaco DNA-hsp65 na lesão pulmonar induzida por bleomicina / Influence of a DNA-hsp65 vaccine on bleomycin-induced lung injury  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Avaliar a influência do biofármaco DNA-hsp65 em um modelo de distúrbio fibrosante pulmonar experimental. MÉTODOS: Foram estudados 120 camundongos machos C57BL/6, divididos em quatro grupos: grupo SS, animais tratados com salina (placebo) e injetados com salina intratraqueal (IT); grupo SB, [...] tratados com salina (placebo) e injetados com bleomicina IT; grupo PB, tratados com plasmídeo, sem gene bacteriano, e injetados com bleomicina IT; e grupo BB, tratados com DNA-hsp65 e injetados com bleomicina IT. A bleomicina foi injetada 15 dias após a última imunização, e os animais sacrificados seis semanas após o uso da droga IT. O pulmão esquerdo retirado foi utilizado para análise morfológica, e o pulmão direito para dosagens de hidroxiprolina. RESULTADOS: A proporção de camundongos que apresentaram morte não-programada depois de 48 h da injeção IT foi maior no grupo SB em comparação ao grupo SS (57,7% vs. 11,1%). A área percentual média de interstício septal foi maior nos grupos SB e PB (53,1 ± 8,6% e 53,6 ± 9,3%, respectivamente) em comparação aos grupos SS e BB (32,9 ± 2,7% e 34,3 ± 6,1%, respectivamente). Os grupos SB, PB e BB mostraram aumentos nos valores médios da área de interstício septal corada por picrosirius em comparação ao grupo SS (SS: 2,0 ± 1,4%; SB: 8,2 ± 4,9%; PB: 7,2 ± 4,2%; e BB:6,6±4,1%).O conteúdo pulmonar de hidroxiprolina no grupo SS foi inferior ao dos demais grupos (SS: 104,9 ± 20,9 pg/pulmão; SB: 160,4 ±47,8 pg/pulmão; PB:170,0 ± 72,0 pg/pulmão; e BB: 162,5 ± 39,7 pg/pulmão). CONCLUSÕES: A imunização com o biofármaco DNA-hsp65 interferiu na deposição de matriz não-colágena em um modelo de lesão pulmonar induzida por bleomicina. Abstract in english OBJECTIVE: To evaluate the effects of immunization with a DNA-hsp65 vaccine in an experimental model of pulmonary fibrosis. METHODS: A total of 120 male C57BL/6 mice were distributed into four groups: SS, injected with saline (placebo) and then receiving intratracheal (IT) instillation of saline; SB [...] , injected with saline (placebo) and then receiving IT instillation of bleomycin; PB, treated with plasmid only, without bacterial genome, and then receiving IT instillation of bleomycin; and BB, treated with the vaccine and then receiving IT instillation of bleomycin. Bleomycin was instilled 15 days after the last immunization, and the animals were killed six weeks thereafter. The left and right lungs were removed, the former for morphological analysis and the latter for hydroxyproline measurements. RESULTS: The proportion of deaths within the first 48 h after the IT instillation (deaths attributed to the surgical procedure) was higher in the SB group than in the SS group (57.7% vs. 11.1%). The mean area of pulmonary interstitial septa was greater in the SB and PB groups (53.1 ± 8.6% and 53.6±9.3%, respectively) than in the SS and BB groups (32.9 ± 2.7% and 34.3 ± 6.1%, respectively). The mean area of interstitial septa stained by picrosirius was greater in the SB, PB and BB groups than in the SS group (8.2 ± 4.9%, 7.2 ± 4.2% and 6.6 ± 4.1%, respectively, vs. 2.0±1.4%). The total hydroxyproline content in the lung was significantly lower in the SS group (104.9 ± 20.9 pg/lung) than in the other groups (SB: 160.4 ± 47.8 pg/lung; PB: 170.0 ± 72.0 pg/lung; and BB: 162.5 ± 39.7 pg/lung). CONCLUSIONS: Immunization with the DNA-hsp65 vaccine reduced the deposition of noncollagen matrix in a model of bleomycin-induced lung lesion.

Adriana Ignacio de, Padua; Célio Lopes, Silva; Simone Gusmão, Ramos; Lúcia Helena, Faccioli; José Antônio Baddini, Martinez.

13

Factors associated with severe granulomatous pneumonia in Mycobacterium tuberculosis-infected mice vaccinated therapeutically with hsp65 DNA.  

Science.gov (United States)

Resistant C57BL/6 mice infected in the lungs with Mycobacterium tuberculosis and then therapeutically vaccinated with Mycobacterium leprae-derived hsp65 DNA develop severe granulomatous pneumonia and tissue damage. Analysis of cells accumulating in the lungs of these animals revealed substantial increases in T cells secreting tumor necrosis factor alpha and CD8 cells staining positive for granzyme B. Stimulation of lung cells ex vivo revealed very high levels of interleukin-10, some of which was produced by B-1 B cells. This was probably an anti-inflammatory response, since lung pathology was dramatically worsened in B-cell gene-disrupted mice. PMID:16041037

Taylor, Jennifer L; Ordway, Diane J; Troudt, Jolynn; Gonzalez-Juarrero, Mercedes; Basaraba, Randall J; Orme, Ian M

2005-08-01

14

hsp65 PCR-restriction enzyme analysis (PRA for identification of mycobacteria in the clinical laboratory  

Directory of Open Access Journals (Sweden)

Full Text Available More than 70 species of mycobacteria have been defined, and some can cause disease in humans, especially in immunocompromised patients. Species identification in most clinical laboratories is based on phenotypic characteristics and biochemical tests and final results are obtained only after two to four weeks. Quick identification methods, by reducing time for diagnosis, could expedite institution of specific treatment, increasing chances of success. PCR restriction-enzyme analysis (PRA of the hsp65 gene was used as a rapid method for identification of 103 clinical isolates. Band patterns were interpreted by comparison with published tables and patterns available at an Internet site (http://www.hospvd.ch:8005. Concordant results of PRA and biochemical identification were obtained in 76 out of 83 isolates (91.5%. Results from 20 isolates could not be compared due to inconclusive PRA or biochemical identification. The results of this work showed that PRA could improve identification of mycobacteria in a routine setting because it is accurate, fast, and cheaper than conventional phenotypic identification.

SILVA Carolina Feher da

2001-01-01

15

Antigen-presenting cells transfected with Hsp65 messenger RNA fail to treat experimental tuberculosis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english In the last several years, the use of dendritic cells has been studied as a therapeutic strategy against tumors. Dendritic cells can be pulsed with peptides or full-length protein, or they can be transfected with DNA or RNA. However, comparative studies suggest that transfecting dendritic cells with [...] messenger RNA (mRNA) is superior to other antigen-loading techniques in generating immunocompetent dendritic cells. In the present study, we evaluated a new therapeutic strategy to fight tuberculosis using dendritic cells and macrophages transfected with Hsp65 mRNA. First, we demonstrated that antigen-presenting cells transfected with Hsp65 mRNA exhibit a higher level of expression of co-stimulatory molecules, suggesting that Hsp65 mRNA has immunostimulatory properties. We also demonstrated that spleen cells obtained from animals immunized with mock and Hsp65 mRNA-transfected dendritic cells were able to generate a mixed Th1/Th2 response with production not only of IFN-? but also of IL-5 and IL-10. In contrast, cells recovered from mice immunized with Hsp65 mRNA-transfected macrophages were able to produce only IL-5. When mice were infected with Mycobacterium tuberculosis and treated with antigen-presenting cells transfected with Hsp65 mRNA (therapeutic immunization), we did not detect any decrease in the lung bacterial load or any preservation of the lung parenchyma, indicating the inability of transfected cells to confer curative effects against tuberculosis. In spite of the lack of therapeutic efficacy, this study reports for the first time the use of antigen-presenting cells transfected with mRNA in experimental tuberculosis.

C.D., Rocha; A.P.F., Trombone; J.C.C., Lorenzi; L.P., Almeida; A.F., Gembre; E., Padilha; S.G., Ramos; C.L., Silva; A.A.M., Coelho-Castelo.

1183-11-01

16

Antigen-presenting cells transfected with Hsp65 messenger RNA fail to treat experimental tuberculosis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english In the last several years, the use of dendritic cells has been studied as a therapeutic strategy against tumors. Dendritic cells can be pulsed with peptides or full-length protein, or they can be transfected with DNA or RNA. However, comparative studies suggest that transfecting dendritic cells with [...] messenger RNA (mRNA) is superior to other antigen-loading techniques in generating immunocompetent dendritic cells. In the present study, we evaluated a new therapeutic strategy to fight tuberculosis using dendritic cells and macrophages transfected with Hsp65 mRNA. First, we demonstrated that antigen-presenting cells transfected with Hsp65 mRNA exhibit a higher level of expression of co-stimulatory molecules, suggesting that Hsp65 mRNA has immunostimulatory properties. We also demonstrated that spleen cells obtained from animals immunized with mock and Hsp65 mRNA-transfected dendritic cells were able to generate a mixed Th1/Th2 response with production not only of IFN-? but also of IL-5 and IL-10. In contrast, cells recovered from mice immunized with Hsp65 mRNA-transfected macrophages were able to produce only IL-5. When mice were infected with Mycobacterium tuberculosis and treated with antigen-presenting cells transfected with Hsp65 mRNA (therapeutic immunization), we did not detect any decrease in the lung bacterial load or any preservation of the lung parenchyma, indicating the inability of transfected cells to confer curative effects against tuberculosis. In spite of the lack of therapeutic efficacy, this study reports for the first time the use of antigen-presenting cells transfected with mRNA in experimental tuberculosis.

C.D., Rocha; A.P.F., Trombone; J.C.C., Lorenzi; L.P., Almeida; A.F., Gembre; E., Padilha; S.G., Ramos; C.L., Silva; A.A.M., Coelho-Castelo.

17

Antigen-presenting cells transfected with Hsp65 messenger RNA fail to treat experimental tuberculosis  

Directory of Open Access Journals (Sweden)

Full Text Available In the last several years, the use of dendritic cells has been studied as a therapeutic strategy against tumors. Dendritic cells can be pulsed with peptides or full-length protein, or they can be transfected with DNA or RNA. However, comparative studies suggest that transfecting dendritic cells with messenger RNA (mRNA is superior to other antigen-loading techniques in generating immunocompetent dendritic cells. In the present study, we evaluated a new therapeutic strategy to fight tuberculosis using dendritic cells and macrophages transfected with Hsp65 mRNA. First, we demonstrated that antigen-presenting cells transfected with Hsp65 mRNA exhibit a higher level of expression of co-stimulatory molecules, suggesting that Hsp65 mRNA has immunostimulatory properties. We also demonstrated that spleen cells obtained from animals immunized with mock and Hsp65 mRNA-transfected dendritic cells were able to generate a mixed Th1/Th2 response with production not only of IFN-? but also of IL-5 and IL-10. In contrast, cells recovered from mice immunized with Hsp65 mRNA-transfected macrophages were able to produce only IL-5. When mice were infected with Mycobacterium tuberculosis and treated with antigen-presenting cells transfected with Hsp65 mRNA (therapeutic immunization, we did not detect any decrease in the lung bacterial load or any preservation of the lung parenchyma, indicating the inability of transfected cells to confer curative effects against tuberculosis. In spite of the lack of therapeutic efficacy, this study reports for the first time the use of antigen-presenting cells transfected with mRNA in experimental tuberculosis.

C.D. Rocha

2012-12-01

18

Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The greatest challenges in vaccine development include optimization of DNA vaccines for use in humans, creation of effective single-dose vaccines, development of delivery systems that do not involve live viruses, and the identification of effective new adjuvants. Herein, we describe a novel, simple technique for efficiently vaccinating mice against tuberculosis (TB. Our technique consists of a single-dose, genetic vaccine formulation of DNA-hsp65 complexed with cationic liposomes and administered intranasally. Results We developed a novel and non-toxic formulation of cationic liposomes, in which the DNA-hsp65 vaccine was entrapped (ENTR-hsp65 or complexed (COMP-hsp65, and used to immunize mice by intramuscular or intranasal routes. Although both liposome formulations induced a typical Th1 pattern of immune response, the intramuscular route of delivery did not reduce the number of bacilli. However, a single intranasal immunization with COMP-hsp65, carrying as few as 25 ?g of plasmid DNA, leads to a remarkable reduction of the amount of bacilli in lungs. These effects were accompanied by increasing levels of IFN-? and lung parenchyma preservation, results similar to those found in mice vaccinated intramuscularly four times with naked DNA-hsp65 (total of 400 ?g. Conclusion Our objective was to overcome the significant obstacles currently facing DNA vaccine development. Our results in the mouse TB model showed that a single intranasal dose of COMP-hsp65 elicited a cellular immune response that was as strong as that induced by four intramuscular doses of naked-DNA. This formulation allowed a 16-fold reduction in the amount of DNA administered. Moreover, we demonstrated that this vaccine is safe, biocompatible, stable, and easily manufactured at a low cost. We believe that this strategy can be applied to human vaccines to TB in a single dose or in prime-boost protocols, leading to a tremendous impact on the control of this infectious disease.

Silva Célio L

2008-07-01

19

Expanding the mycobacterial diversity of metalworking fluids (MWFs): evidence showing MWF colonization by Mycobacterium abscessus.  

Science.gov (United States)

Nontuberculous mycobacteria (NTM) have been associated with hypersensitivity pneumonitis in machinists. Only two species of NTM, namely Mycobacterium immunogenum and Mycobacterium chelonae, have been reported thus far to have the ability to colonize contaminated metalworking fluids (MWFs). Here, we report, for the first time, the presence and characterization (phenotypic and genotypic) of a third species, Mycobacterium abscessus, colonizing these harsh alkaline machining fluids. Two Mycobacterium morphotypes, smooth (S) and rough (R), were isolated (two isolates each) from an in-use industrial MWFs. Biocide susceptibility analysis using triclosan as a model yielded the same minimal inhibitory concentration for the two morphotypes. PCR-restriction analysis-based speciation of the morphotypes confirmed their identity as M. abscessus. Genotyping based on partial DNA sequences corresponding to the variable regions of the hsp65 gene and 16S-23S rRNA operon internal transcribed spacer region and randomly amplified polymorphic DNA-PCR analysis showed that both morphotypes belong to a single genotype. In addition, we isolated and confirmed two novel mycobacterial genotypes, one each of M. immunogenum and M. chelonae from additional in-use MWF screening. Taken together, this study expands the known mycobacterial species- and strain-diversity colonizing MWF. Furthermore, the study emphasizes the need for including M. abscessus species in the existing mycobacterial screening of contaminated MWF. PMID:22092754

Kapoor, Renuka; Yadav, Jagjit S

2012-02-01

20

The 'tubulin-like' S1 protein of Spirochaeta is a member of the hsp65 stress protein family  

Science.gov (United States)

A 65-kDa protein (called S1) from Spirochaeta bajacaliforniensis was identified as 'tubulin-like' because it cross-reacted with at least four different antisera raised against tubulin and was isolated, with a co-polymerizing 45-kDa protein, by warm-cold cycling procedures used to purify tubulin from mammalian brain. Furthermore, at least three genera of non-cultivable symbiotic spirochetes (Pillotina, Diplocalyx, and Hollandina) that contain conspicuous 24-nm cytoplasmic tubules displayed a strong fluorescence in situ when treated with polyclonal antisera raised against tubulin. Here we summarize results that lead to the conclusion that this 65-kDa protein has no homology to tubulin. S1 is an hsp65 stress protein homologue. Hsp65 is a highly immunogenic family of hsp60 proteins which includes the 65-kDa antigens of Mycobacterium tuberculosis (an active component of Freund's complete adjuvant), Borrelia, Treponema, Chlamydia, Legionella, and Salmonella. The hsp60s, also known as chaperonins, include E. coli GroEL, mitochondrial and chloroplast chaperonins, the pea aphid 'symbionin' and many other proteins involved in protein folding and the stress response.

Munson, D.; Obar, R.; Tzertzinis, G.; Margulis, L.

1993-01-01

 
 
 
 
21

Mycobacterial Gene cuvA Is Required for Optimal Nutrient Utilization and Virulence.  

Science.gov (United States)

To persist and cause disease in the host, Mycobacterium tuberculosis must adapt to its environment during infection. Adaptations include changes in nutrient utilization and alterations in growth rate. M. tuberculosis Rv1422 is a conserved gene of unknown function that was found in a genetic screen to interact with the mce4 cholesterol uptake locus. The Rv1422 protein is phosphorylated by the M. tuberculosis Ser/Thr kinases PknA and PknB, which regulate cell growth and cell wall synthesis. Bacillus subtilis strains lacking the Rv1422 homologue yvcK grow poorly on several carbon sources, and yvcK is required for proper localization of peptidoglycan synthesis. Here we show that Mycobacterium smegmatis and M. tuberculosis strains lacking Rv1422 have growth defects in minimal medium containing limiting amounts of several different carbon sources. These strains also have morphological abnormalities, including shortened and bulging cells, suggesting a cell wall defect. In both mycobacterial species, the Rv1422 protein localizes uniquely to the growing cell pole, the site of peptidoglycan synthesis in mycobacteria. An M. tuberculosis ?Rv1422 strain is markedly attenuated for virulence in a mouse infection model, where it elicits decreased inflammation in the lungs and shows impaired bacterial persistence. These findings led us to name this gene cuvA (carbon utilization and virulence protein A) and to suggest a model in which deletion of cuvA leads to changes in nutrient uptake and/or metabolism that affect cell wall structure, morphology, and virulence. Its role in virulence suggests that CuvA may be a useful target for novel inhibitors of M. tuberculosis during infection. PMID:25047842

Mir, Mushtaq; Prisic, Sladjana; Kang, Choong-Min; Lun, Shichun; Guo, Haidan; Murry, Jeffrey P; Rubin, Eric J; Husson, Robert N

2014-10-01

22

Oral administration of recombinant Lactococcus lactis expressing HSP65 and tandemly repeated P277 reduces the incidence of type I diabetes in non-obese diabetic mice.  

Science.gov (United States)

Diabetes mellitus type 1 (DM1) is an autoimmune disease that gradually destroys insulin-producing beta-cells. We have previously reported that mucosal administration of fusion protein of HSP65 with tandem repeats of P277 (HSP65-6P277) can reduce the onset of DM1 in non-obese diabetic (NOD) mice. To deliver large amounts of the fusion protein and to enhance long-term immune tolerance effects, in the present study, we investigated the efficacy of using orally administrated L. lactis expressing HSP65-6P277 to reduce the incidence of DM1 in NOD mice. L. lactis strain NZ9000 was engineered to express HSP65-6P277 either constitutively or by nisin induction. After immunization via gavage with the recombinant L. lactis strains to groups of 4-week old female NOD mice for 36 weeks, we observed that oral administration of recombinant L. Lactis resulted in the prevention of hyperglycemia, improved glucose tolerance and reduced insulitis. Immunologic analysis showed that treatment with recombinant L. lactis induced HSP65- and P277- specific T cell immuno-tolerance, as well as antigen-specific proliferation of splenocytes. The results revealed that the DM1-preventing function was in part caused by a reduction in the pro-inflammatory cytokine IFN-? and an increase in the anti-inflammatory cytokine IL-10. Orally administered recombinant L. lactis delivering HSP65-6P277 may be an effective therapeutic approach in preventing DM1. PMID:25157497

Ma, Yanjun; Liu, Jingjing; Hou, Jing; Dong, Yuankai; Lu, Yong; Jin, Liang; Cao, Rongyue; Li, Taiming; Wu, Jie

2014-01-01

23

Immunization of low-density lipoprotein receptor deficient (LDL-RD) mice with heat shock protein 65 (HSP-65) promotes early atherosclerosis.  

Science.gov (United States)

Heat shock proteins are a family of approximately 25 highly conserved proteins upregulated in response to various forms of stress. They play an active role in the development autoimmune diseases in animals, and have been incriminated in human autoimmune diseases (i.e. rheumatoid arthritis, multiple sclerosis). It has been previously shown, that an induced immune response against Heat shock protein 65 (HSP-65) results in atherosclerotic lesions in normocholesterolemic rabbits. We have supported these findings showing that C57BL/6 mice immunized with HSP-65 and fed a high-fat diet develop enhanced fatty streaks. To create a model that will eliminate the need for exogenous supplementation of a high-fat diet, we have immunized LDL receptor deficient (LDL-RD) mice with HSP-65 or with heat-killed Mycobacterium tuberculosis (Mt). Seven groups of LDL-RD mice (n=10), were immunized subcutaneously with different concentrations of HSP-65, Mt or bovine serum albumin (BSA). All mice were fed a normal chow-diet for 3 months. The mice immunized with the higher doses of Mt developed significantly larger fatty streaks when compared with their BSA immunized littermates. The size of the lesions in the aortic sinus were: 31,562+/-5,994 microm(2)in the 10 microg Mt and 52,777+/-5,245 microm(2)in the 100 microg Mt vs. 11, 500+/-3,750 microm(2)in the BSA group (Pvs. 11,500+/-3,750 microm(2)respectively, (Pfat diet supplementation. This model will enable us to further study the role of the immune system in atherosclerosis, via HSP-65 and raise novel immunomodulatory therapeutic modalities. PMID:10677242

Afek, A; George, J; Gilburd, B; Rauova, L; Goldberg, I; Kopolovic, J; Harats, D; Shoenfeld, Y

2000-03-01

24

Mycobacterial dermatitis.  

Science.gov (United States)

Mycobacterial skin disease in cats associated with atypical mycobacteria is an uncommon disease in small animal practice, and the disease is rarely encountered in dogs. A mycobacterial etiology should be considered in cases of chronic nodular dermatitis, draining tracts, and panniculitis. Cats and dogs affected with atypical mycobacterial infections are usually otherwise healthy, and systemic illness is unusual. In most cases, a diagnosis is made based on histopathological findings and growth of a causative organism. Group IV atypical mycobacteria can usually be grown following submission of affected tissue. Treatment should be based on antibiotic sensitivity test results. Treatment is prolonged and is unsuccessful in many cases. In cases of feline leprosy and canine leproid granuloma syndrome, organisms are difficult if not impossible to grow, and clinical and histopathological findings should be used to make a diagnosis. Spontaneous resolution of disease has been reported in atypical mycobacteriosis, feline leprosy, and canine leproid granuloma syndrome. PMID:10563000

Lemarie, S L

1999-11-01

25

Enhanced immune response of a bicistronic DNA vaccine expressing fusion antigen Hsp65-Esat-6 of Mycobacterium Tuberculosis with GM-CSF as a molecular adjuvant  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english This study aimed to construct a bicistronic DNA vaccine expressing fusion antigen Hsp65-Esat-6 of Mycobacterium tuberculosis with cytokine GM-CSF as a molecular adjuvant (pIRES-Hsp65-ESAT-6-GM-CSF, pIRHEG), and the immune response in mice. C57BL/6 mice were immunized with the recombinant plasmid to [...] detect the titer of antibodies, lymphocyte proliferation, the ratio of CD4+, CD8+T cell and IFN ~ ?,IL-2 secretion. The titer of antibody, lymphocyte proliferation, the ratio of CD4+T and CD8+T cells and IFN ~ ?, IL-2 secretion of pIRHEG group was significant higher than other recombinant plasmid groups, which significant differed by statistical mean. The bicistronic DNA vaccine could induce an effective immune response in mice and could be used as vital ingredient of a new tuberculosis vaccine candidate.

Yan, Dong; Jun-Yuan, Gong; Xin, Liu; Jun-Wu, Li.

26

Enhanced immune response of a bicistronic DNA vaccine expressing fusion antigen Hsp65-Esat-6 of Mycobacterium Tuberculosis with GM-CSF as a molecular adjuvant  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english This study aimed to construct a bicistronic DNA vaccine expressing fusion antigen Hsp65-Esat-6 of Mycobacterium tuberculosis with cytokine GM-CSF as a molecular adjuvant (pIRES-Hsp65-ESAT-6-GM-CSF, pIRHEG), and the immune response in mice. C57BL/6 mice were immunized with the recombinant plasmid to [...] detect the titer of antibodies, lymphocyte proliferation, the ratio of CD4+, CD8+T cell and IFN ~ ?,IL-2 secretion. The titer of antibody, lymphocyte proliferation, the ratio of CD4+T and CD8+T cells and IFN ~ ?, IL-2 secretion of pIRHEG group was significant higher than other recombinant plasmid groups, which significant differed by statistical mean. The bicistronic DNA vaccine could induce an effective immune response in mice and could be used as vital ingredient of a new tuberculosis vaccine candidate.

Yan, Dong; Jun-Yuan, Gong; Xin, Liu; Jun-Wu, Li.

2013-10-01

27

Gene encoded antimicrobial peptides, a template for the design of novel anti-mycobacterial drugs.  

Science.gov (United States)

Nisin A is the most widely characterized lantibiotic investigated to date. It represents one of the many antimicrobial peptides which have been the focus of much interest as potential therapeutic agents. This has resulted in the search for novel lantibiotics and more commonly, the engineering of novel variants from existing peptides with a view to increasing their activity, stability and solubility.The aim of this study was to compare the activities of nisin A and novel bioengineered hinge derivatives, nisin S, nisin T and nisin V. The microtitre alamar blue assay (MABA) was employed to identify the enhanced activity of these novel variants against M. tuberculosis (H37Ra), M. kansasii (CIT11/06), M. avium subsp. hominissuis (CIT05/03) and M. avium subsp. paratuberculosis (MAP) (ATCC 19698). All variants displayed greater anti-mycobacterial activity than nisin A. Nisin S was the most potent variant against M. tuberculosis, M. kansasii and M. avium subsp. hominissuis, retarding growth by a maximum of 29% when compared with nisin A. Sub-species variations of inhibition were also observed with nisin S reducing growth of Mycobacterium avium subsp. hominissuis by 28% and Mycobacterium avium subsp. paratuberculosis by 19% and nisin T contrastingly reducing growth of MAP by 27% and MAC by 16%.Nisin S, nisin T and nisin V are potent novel anti-mycobacterial compounds, which have the capacity to be further modified, potentially generating compounds with additional beneficial characteristics. This is the first report to demonstrate an enhancement of efficacy by any bioengineered bacteriocin against mycobacteria. PMID:21468208

Carroll, James; Field, Des; O'Connor, Paula M; Cotter, Paul D; Coffey, Aidan; Hill, Colin; Ross, R Paul; O'Mahony, Jim

2010-01-01

28

Molecular Characterization of Heterologous HIV-1gp120 Gene Expression Disruption in Mycobacterium bovis BCG Host Strain: A Critical Issue for Engineering Mycobacterial Based-Vaccine Vectors  

Directory of Open Access Journals (Sweden)

Full Text Available Mycobacterium bovis Bacillus Calmette-Guérin (BCG as a live vector of recombinant bacterial vaccine is a promising system to be used. In this study, we evaluate the disrupted expression of heterologous HIV-1gp120 gene in BCG Pasteur host strain using replicative vectors pMV261 and pJH222. pJH222 carries a lysine complementing gene in BCG lysine auxotrophs. The HIV-1 gp120 gene expression was regulated by BCG hsp60 promoter (in plasmid pMV261 and Mycobacteria spp. ?-antigen promoter (in plasmid pJH222. Among 14 rBCG:HIV-1gp120 (pMV261 colonies screened, 12 showed a partial deletion and two showed a complete deletion. However, deletion was not observed in all 10 rBCG:HIV-1gp120 (pJH222 colonies screened. In this study, we demonstrated that E. coli/Mycobacterial expression vectors bearing a weak promoter and lysine complementing gene in a recombinant lysine auxotroph of BCG could prevent genetic rearrangements and disruption of HIV 1gp120 gene expression, a key issue for engineering Mycobacterial based vaccine vectors.

Joan Joseph

2010-01-01

29

Identification by 16S rRNA gene analyses of a potential novel mycobacterial species as an etiological agent of canine leproid granuloma syndrome.  

Science.gov (United States)

PCR amplifications of the 16S rRNA gene were performed on 46 specimens obtained from 43 dogs with canine leproid granuloma syndrome to help determine its etiology. Sequence capture PCR was applied to 37 paraffin-embedded specimens from 37 dogs, and nested PCR was attempted on DNA from 9 fresh tissue specimens derived from 3 of the 37 aforementioned dogs and from an additional 6 dogs. Molecular analyses of the paraffin-embedded tissues and fresh tissue specimen analyses were performed at separate institutions. PCR products with identical sequences over a 350-bp region encompassing variable regions 2 and 3 of the 16S rRNA gene were obtained from 4 of 37 paraffin-embedded specimens and from all 9 specimens of fresh tissue originating from 12 of the 43 dogs. Identical sequences were determined from amplicons obtained from paraffin-embedded and fresh specimens from one dog. The consensus DNA sequence, amplified from paraffin-embedded tissue and represented by GenBank accession no. AF144747, shared highest nucleotide identity (99.4% over 519 bp) with mycobacterial strain IWGMT 90413 but did not correspond exactly to any EMBL or GenBank database sequence. With a probe derived from the V2 region of the novel canine sequence, reverse cross blot hybridization identified an additional four paraffin-embedded specimens containing the same novel sequence. In total, molecular methodologies identified the proposed novel mycobacterial sequence in 16 of 43 dogs with canine leproid granuloma syndrome, indicating that the species represented by this sequence may be the principal etiological agent of canine leproid granuloma syndrome. PMID:10698979

Hughes, M S; James, G; Ball, N; Scally, M; Malik, R; Wigney, D I; Martin, P; Chen, S; Mitchell, D; Love, D N

2000-03-01

30

Deletion of a mycobacterial gene encoding a reductase leads to an altered cell wall containing ?-oxo-mycolic acid analogues, and the accumulation of longchain ketones related to mycolic acids.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mycolic acids are essential components of the mycobacterial cell wall. In this study we show that a gene encoding a reductase involved in the final step of mycolic acid biosynthesis can be deleted in Mycobacterium smegmatis without affecting cell viability. Deletion of MSMEG4722 (ortholog of Mycobacterium tuberculosis Rv2509) altered culture characteristics and antibiotic sensitivity. The ?MSMEG4722 strain synthesized ?-alkyl, ?-oxo intermediates of mycolic acids which were found esterifie...

Bhatt, Apoorva; Brown, Alistair K.; Singh, Albel; Minnikin, David E.; Besra, Gurdyal S.

2008-01-01

31

Biosynthesis of mycobacterial methylglucose lipopolysaccharides.  

Science.gov (United States)

Mycobacterial pathogenesis is closely associated with a unique cell envelope rich in complex carbohydrates and unique lipids, among which are the mycolic acids. Mycobacteria also synthesize unique intracellular polymethylated polysaccharides (PMPSs), namely methylglucose lipopolysaccharides (MGLPs), which are acylated with short-chain fatty acids, and methylmannose polysaccharides (MMPs). Since PMPSs modulate the synthesis of long-chain fatty acids in vitro, the possibility of a similar role in vivo and the regulation of mycolic acids assembly have been anticipated. Unlike MGLPs, MMPs have been identified in M. smegmatis and other fast-growing mycobacteria but not in M. tuberculosis, implying an essential role for MGLPs in this pathogen and turning the biosynthetic enzymes into attractive drug targets. The genome of M. tuberculosis was decoded 14 years ago but only recently has the identity of the genes involved in MGLPs biosynthesis been investigated. Two gene clusters (Rv1208-Rv1213 and Rv3030-Rv3037c) containing a few genes considered to be essential for M. tuberculosis growth, have initially been proposed to coordinate MGLPs biosynthesis. Among these genes, only the product of Rv1208 for the first step in the MGLPs pathway has, so far, been crystallized and its three-dimensional structure been determined. However, recent results indicate that at least three additional clusters may be involved in this pathway. The functional assignment of authentic roles to some of these M. tuberculosis H37Rv genes sheds new light on the intricacy of MGLPs biogenesis and renewed interest on their biological role. PMID:22678749

Mendes, Vitor; Maranha, Ana; Alarico, Susana; Empadinhas, Nuno

2012-08-01

32

Mutational analysis of the mycobacteriophage BPs promoter PR reveals context-dependent sequences for mycobacterial gene expression.  

Science.gov (United States)

The PR promoter of mycobacteriophage BPs directs early lytic gene expression and is under the control of the BPs repressor, gp33. Reporter gene fusions showed that PR has modest activity in an extrachromosomal context but has activity that is barely detectable in an integrated context, even in the absence of its repressor. Mutational dissection of PR showed that it uses a canonical -10 hexamer recognized by SigA, and mutants with mutations to the sequence 5'-TATAMT had the greatest activities. It does not contain a 5'-TGN-extended -10 sequence, although mutants with mutations creating an extended -10 sequence had substantially increased promoter activity. Mutations in the -35 hexamer also influenced promoter activity but were strongly context dependent, and similar substitutions in the -35 hexamer differentially affected promoter activity, depending on the -10 and extended -10 motifs. This warrants caution in the construction of synthetic promoters or the bioinformatic prediction of promoter activity. Combinations of mutations throughout PR generated a calibrated series of promoters for expression of stably integrated recombinant genes in both Mycobacterium smegmatis and M. tuberculosis, with maximal promoter activity being more than 2-fold that of the strong hsp60 promoter. PMID:25092027

Oldfield, Lauren M; Hatfull, Graham F

2014-10-01

33

[Biologics and mycobacterial diseases].  

Science.gov (United States)

Various biologics such as TNF-alpha inhibitor or IL-6 inhibitor are now widely used for treatment of rheumatoid arthritis. Many reports suggested that one of the major issues is high risk of developing tuberculosis (TB) associated with using these agents, which is especially important in Japan where tuberculosis still remains endemic. Another concern is the risk of development of nontuberculous mycobacterial (NTM) diseases and we have only scanty information about it. The purpose of this symposium is to elucidate the role of biologics in the development of mycobacterial diseases and to establish the strategy to control them. First, Dr. Tohma showed the epidemiologic data of TB risks associated with using biologics calculated from the clinical database on National Database of Rheumatic Diseases by iR-net in Japan. He estimated TB risks in rheumatoid arthritis (RA) patients to be about four times higher compared with general populations and to become even higher by using biologics. He also pointed out a low rate of implementation of QuantiFERON test (QFT) as screening test for TB infection. Next, Dr. Tokuda discussed the issue of NTM disease associated with using biologics. He suggested the airway disease in RA patients might play some role in the development of NTM disease, which may conversely lead to overdiagnosis of NTM disease in RA patients. He suggested that NTM disease should not be uniformly considered a contraindication to treatment with biologics, considering from the results of recent multicenter study showing relatively favorable outcome of NTM patients receiving biologics. Patients with latent tuberculosis infection (LTBI) should receive LTBI treatment before starting biologics. Dr. Kato, a chairperson of the Prevention Committee of the Japanese Society for Tuberculosis, proposed a new LTBI guideline including active implementation of LTBI treatment, introducing interferon gamma release assay, and appropriate selection of persons at high risk for developing TB. Lastly, Dr. Matsumoto stressed the risk of discontinuing TNF-alpha inhibitor during treatment for tuberculosis. He showed from his clinical experience that TNF-alpha inhibitor can be safely used in active TB patient receiving effective antituberculosis chemotherapy and it is even more effective for prevention of paradoxical response. Active discussion was done about the four topics, including the matter beyond present guidelines. We hope these discussions will form the basis for the establishment of new guideline for the management of mycobacterial disease when using immunosuppressive agents including biologics. 1. The risk of developing tuberculosis (TB) and situations of screening for TB risk at administration of biologics-the case of rheumatoid arthritis: Shigeto TOHMA (Clinical Research Center for Allergy and Rheumatology, National Hospital Organization Sagamihara National Hospital) We calculated the standardized incidence ratio (SIR) of TB from the clinical data on National Database of Rheumatic Diseases by iR-net in Japan (NinJa) and compared with the SIR of TB from the data of the post-marketing surveillances of five biologics. Among 43584 patient-years, forty patients developed TB. The SIR of TB in NinJa was 4.34 (95%CI: 3.00-5.69). According to the post-marketing surveillances of 5 biologics, the SIR of TB were 3.62-34.4. The incidence of TB in patients with RA was higher than general population in Japan, and was increased more by some biologics. We have to recognize the risk of TB when we start biologics therapy to patients with RA. Although the frequency of implementation of QuantiFERON test (QFT) had gradually increased, it was still limited to 41%. In order to predict the risk of developing TB and to prevent TB, it might be better to check all RA patients by QFT at time time of biologics administration. 2. Biologics and nontuberculous mycobacterial diseases: Hitoshi TOKUDA (Social Insurance Central General Hospital) Several topics about the relationship between RA and nontuberculous mycobacterial (NTM) diseases were discussed, which is sti

Tsuyuguchi, Kazunari; Matsumoto, Tomoshige

2013-03-01

34

Phosphorylation regulates mycobacterial proteasome.  

Science.gov (United States)

Mycobacterium tuberculosis possesses a proteasome system that is required for the microbe to resist elimination by the host immune system. Despite the importance of the proteasome in the pathogenesis of tuberculosis, the molecular mechanisms by which proteasome activity is controlled remain largely unknown. Here, we demonstrate that the ?-subunit (PrcA) of the M. tuberculosis proteasome is phosphorylated by the PknB kinase at three threonine residues (T84, T202, and T178) in a sequential manner. Furthermore, the proteasome with phosphorylated PrcA enhances the degradation of Ino1, a known proteasomal substrate, suggesting that PknB regulates the proteolytic activity of the proteasome. Previous studies showed that depletion of the proteasome and the proteasome-associated proteins decreases resistance to reactive nitrogen intermediates (RNIs) but increases resistance to hydrogen peroxide (H2O2). Here we show that PknA phosphorylation of unprocessed proteasome ?-subunit (pre-PrcB) and ?-subunit reduces the assembly of the proteasome complex and thereby enhances the mycobacterial resistance to H2O2 and that H2O2 stress diminishes the formation of the proteasome complex in a PknA-dependent manner. These findings indicate that phosphorylation of the M. tuberculosis proteasome not only modulates proteolytic activity of the proteasome, but also affects the proteasome complex formation contributing to the survival of M. tuberculosis under oxidative stress conditions. PMID:25224505

Anandan, Tripti; Han, Jaeil; Baun, Heather; Nyayapathy, Seeta; Brown, Jacob T; Dial, Rebekah L; Moltalvo, Juan A; Kim, Min-Seon; Yang, Seung Hwan; Ronning, Donald R; Husson, Robert N; Suh, Joowon; Kang, Choong-Min

2014-09-01

35

Phenotypic heterogeneity in mycobacterial stringent response  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background A common survival strategy of microorganisms subjected to stress involves the generation of phenotypic heterogeneity in the isogenic microbial population enabling a subset of the population to survive under stress. In a recent study, a mycobacterial population of M. smegmatis was shown to develop phenotypic heterogeneity under nutrient depletion. The observed heterogeneity is in the form of a bimodal distribution of the expression levels of the Green Fluorescent Protein (GFP as reporter with the gfp fused to the promoter of the rel gene. The stringent response pathway is initiated in the subpopulation with high rel activity. Results In the present study, we characterise quantitatively the single cell promoter activity of the three key genes, namely, mprA, sigE and rel, in the stringent response pathway with gfp as the reporter. The origin of bimodality in the GFP distribution lies in two stable expression states, i.e., bistability. We develop a theoretical model to study the dynamics of the stringent response pathway. The model incorporates a recently proposed mechanism of bistability based on positive feedback and cell growth retardation due to protein synthesis. Based on flow cytometry data, we establish that the distribution of GFP levels in the mycobacterial population at any point of time is a linear superposition of two invariant distributions, one Gaussian and the other lognormal, with only the coefficients in the linear combination depending on time. This allows us to use a binning algorithm and determine the time variation of the mean protein level, the fraction of cells in a subpopulation and also the coefficient of variation, a measure of gene expression noise. Conclusions The results of the theoretical model along with a comprehensive analysis of the flow cytometry data provide definitive evidence for the coexistence of two subpopulations with overlapping protein distributions.

Bose Indrani

2011-01-01

36

Cutaneous mycobacterial spindle cell pseudotumour.  

Science.gov (United States)

Mycobacterial spindle cell pseudotumour (MSCP) has been reported in various sites, including skin, lymph nodes, bone marrow, lung and spleen. Cutaneous lesions are extremely rare and the differential diagnoses include various spindle cell lesions. Literature review shows that this lesion has preponderance for upper limb involvement and occurs largely in immunosuppressed individuals. We report a case of MSCP of the skin due to atypical mycobacterium and discuss the risk of misdiagnosis as a sarcoma. PMID:21686408

Tan, Geok Chin; Yap, Yen Piow; Shiran, Mohd Sidik; Sabariah, Abdul Rahman; Pathmanathan, Rajadurai

2009-01-01

37

The essential mycobacterial genes, fabG1 and fabG4, encode 3-oxoacyl-thioester reductases that are functional in yeast mitochondrial fatty acid synthase type 2  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mycobacterium tuberculosis represents a severe threat to human health worldwide. Therefore, it is important to expand our knowledge of vital mycobacterial processes, such as that effected by fatty acid synthase type 2 (FASII), as well as to uncover novel ones. Mycobacterial FASII undertakes mycolic acid biosynthesis, which relies on a set of essential enzymes, including 3-oxoacyl-AcpM reductase FabG1/Rv1483. However, the M. tuberculosis genome encodes four additional FabG homologs, designated...

Gurvitz, Aner

2009-01-01

38

Protein Turnover in Mycobacterial Proteomics  

Directory of Open Access Journals (Sweden)

Full Text Available Understanding the biology of Mycobacterium tuberculosis is one of the primary challenges in current tuberculosis research. Investigation of mycobacterial biology using the systems biology approach has deciphered much information with regard to the bacilli and tuberculosis pathogenesis. The modulation of its environment and the ability to enter a dormant phase are the hallmarks of M. tuberculosis. Until now, proteome studies have been able to understand much about the role of various proteins, mostly in growing M. tuberculosis cells. It has been difficult to study dormant M. tuberculosis by conventional proteomic techniques with very few proteins being found to be differentially expressed. Discrepancy between proteome and transcriptome studies lead to the conclusion that a certain aspect of the mycobacterial proteome is not being explored. Analysis of protein turnover may be the answer to this dilemma. This review, while giving a gist of the proteome response of mycobacteria to various stresses, analyzes the data obtained from abundance studies versus data from protein turnover studies in M. tuberculosis. This review brings forth the point that protein turnover analysis is capable of discerning more subtle changes in protein synthesis, degradation, and secretion activities. Thus, turnover studies could be incorporated to provide a more in-depth view into the proteome, especially in dormant or persistent cells. Turnover analysis might prove helpful in drug discovery and a better understanding of the dynamic nature of the proteome of mycobacteria.

Prahlad K. Rao

2009-08-01

39

Mycobacterial mutants with defective control of phagosomal acidification.  

Directory of Open Access Journals (Sweden)

Full Text Available The pathogenesis of mycobacterial infection is associated with an ability to interfere with maturation of the phagosomal compartment after ingestion by macrophages. Identification of the mycobacterial components that contribute to this phenomenon will allow rational design of novel approaches to the treatment and prevention of tuberculosis. Microarray-based screening of a transposon library was used to identify mutations that influence the fate of Mycobacterium bovis bacille Calmette-Guérin (BCG following uptake by macrophages. A screen based on bacterial survival during a 3-d infection highlighted genes previously implicated in growth of Mycobacterium tuberculosis in macrophages and in mice, together with a number of other virulence genes including a locus encoding virulence-associated membrane proteins and a series of transporter molecules. A second screen based on separation of acidified and non-acidified phagosomes by flow cytometry identified genes involved in mycobacterial control of early acidification. This included the KefB potassium/proton antiport. Mutants unable to control early acidification were significantly attenuated for growth during 6-d infections of macrophages. Early acidification of the phagosome is associated with reduced survival of BCG in macrophages. A strong correlation exists between genes required for intracellular survival of BCG and those required for growth of M. tuberculosis in mice. In contrast, very little correlation exists between genes required for intracellular survival of BCG and those that are up-regulated during intracellular adaptation of M. tuberculosis. This study has identified targets for interventions to promote immune clearance of tuberculosis infection. The screening technologies demonstrated in this study will be useful to the study of pathogenesis in many other intracellular microorganisms.

2005-11-01

40

Mycobacterial species as case-study of comparative genome analysis  

DEFF Research Database (Denmark)

The genus Mycobacterium represents more than 120 species including important pathogens of human and cause major public health problems and illnesses. Further, with more than 100 genome sequences from this genus, comparative genome analysis can provide new insights for better understanding the evolutionary events of these species and improving drugs, vaccines, and diagnostics tools for controlling Mycobacterial diseases. In this present study we aim to outline a comparative genome analysis of fourteen Mycobacterial genomes: M. avium subsp. paratuberculosis K—10, M. bovis AF2122/97, M. bovis BCG str. Pasteur 1173P2, M. leprae Br4923, M. marinum M, M. sp. KMS, M. sp. MCS, M. tuberculosis CDC1551, M. tuberculosis F11, M. tuberculosis H37Ra, M. tuberculosis H37Rv, M. tuberculosis KZN 1435 , M. ulcerans Agy99,and M. vanbaalenii PYR—1, For this purpose a comparison has been done based on their length of genomes, GC content, number of genes in different data bases (Genbank, Refseq, and Prodigal). The BLAST matrix of these genomes has been figured to give a lot of information about the similarity between species in a simple scheme. As a result of multiple genome analysis, the pan and core genome have been defined for twelve Mycobacterial species. We have also introduced the genome atlas of the reference strain M. tuberculosis H37Rv which can give a good overview of this genome. And for examining the phylogenetic relationships among these bacteria, a phylogenic tree has been constructed from 16S rRNA gene for tuberculosis and non tuberculosis Mycobacteria to understand the evolutionary events of these species.

Ussery, David

2011-01-01

 
 
 
 
41

Mycobacterial species as case-study of comparative genome analysis.  

Science.gov (United States)

The genus Mycobacterium represents more than 120 species including important pathogens of human and cause major public health problems and illnesses. Further, with more than 100 genome sequences from this genus, comparative genome analysis can provide new insights for better understanding the evolutionary events of these species and improving drugs, vaccines, and diagnostics tools for controlling Mycobacterial diseases. In this present study we aim to outline a comparative genome analysis of fourteen Mycobacterial genomes: M. avium subsp. paratuberculosis K—10, M. bovis AF2122/97, M. bovis BCG str. Pasteur 1173P2, M. leprae Br4923, M. marinum M, M. sp. KMS, M. sp. MCS, M. tuberculosis CDC1551, M. tuberculosis F11, M. tuberculosis H37Ra, M. tuberculosis H37Rv, M. tuberculosis KZN 1435 , M. ulcerans Agy99,and M. vanbaalenii PYR—1, For this purpose a comparison has been done based on their length of genomes, GC content, number of genes in different data bases (Genbank, Refseq, and Prodigal). The BLAST matrix of these genomes has been figured to give a lot of information about the similarity between species in a simple scheme. As a result of multiple genome analysis, the pan and core genome have been defined for twelve Mycobacterial species. We have also introduced the genome atlas of the reference strain M. tuberculosis H37Rv which can give a good overview of this genome. And for examining the phylogenetic relationships among these bacteria, a phylogenic tree has been constructed from 16S rRNA gene for tuberculosis and non tuberculosis Mycobacteria to understand the evolutionary events of these species. PMID:21396338

Zakham, F; Belayachi, L; Ussery, D; Akrim, M; Benjouad, A; El Aouad, R; Ennaji, M M

2011-01-01

42

CD36 deficiency attenuates experimental mycobacterial infection  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Members of the CD36 scavenger receptor family have been implicated as sensors of microbial products that mediate phagocytosis and inflammation in response to a broad range of pathogens. We investigated the role of CD36 in host response to mycobacterial infection. Methods Experimental Mycobacterium bovis Bacillus Calmette-Guérin (BCG infection in Cd36+/+ and Cd36-/- mice, and in vitro co-cultivation of M. tuberculosis, BCG and M. marinum with Cd36+/+ and Cd36-/-murine macrophages. Results Using an in vivo model of BCG infection in Cd36+/+ and Cd36-/- mice, we found that mycobacterial burden in liver and spleen is reduced (83% lower peak splenic colony forming units, p Cd36-/- animals. Intracellular growth of all three mycobacterial species was reduced in Cd36-/- relative to wild type Cd36+/+ macrophages in vitro. This difference was not attributable to alterations in mycobacterial uptake, macrophage viability, rate of macrophage apoptosis, production of reactive oxygen and/or nitrogen species, TNF or interleukin-10. Using an in vitro model designed to recapitulate cellular events implicated in mycobacterial infection and dissemination in vivo (i.e., phagocytosis of apoptotic macrophages containing mycobacteria, we demonstrated reduced recovery of viable mycobacteria within Cd36-/- macrophages. Conclusions Together, these data indicate that CD36 deficiency confers resistance to mycobacterial infection. This observation is best explained by reduced intracellular survival of mycobacteria in the Cd36-/- macrophage and a role for CD36 in the cellular events involved in granuloma formation that promote early bacterial expansion and dissemination.

Min-Oo Gundula

2010-10-01

43

Modulation of pulmonary dendritic cell function during mycobacterial infection.  

Science.gov (United States)

We have previously reported that during mycobacterial infection, naïve CD4(+) T-cell activation is enhanced in the lungs. We investigated the role of chemokine receptor CCR7 and its ligands in the ability of CD11c(+) lung dendritic cells (DCs) to activate naïve CD4(+) T cells during pulmonary infection with Mycobacterium bovis bacillus Calmette-Guérin (BCG). BCG infection resulted in the accumulation and maturation in the lungs of DCs that persisted as the mycobacterial burden declined. Lung DCs from infected mice expressed more major histocompatibility complex class II (MHC-II) than those from uninfected mice. CCR7 expression levels on lung DCs were comparable among uninfected and infected mice. The gene expression of the CCR7 ligand CCL19 progressively increased throughout BCG infection, and its expression was MyD88 dependent. CD11c(+) lung cells from BCG-infected mice activated ovalbumin (OVA)-specific naïve CD4(+) T cells more than CD11c(+) lung cells from uninfected mice. Interestingly, during peak mycobacterial infection, CD11c(hi) MHC(hi) lung DCs had slightly decreased chemotaxis toward the CCR7 ligand CCL21 and less efficiency in activating naive CD4(+) T cells than DCs from mice during late-stage infection, when few bacilli are found in the lung. These findings suggest that during BCG infection, the inflammation and sustained expression of CCL19 result in the recruitment, activation, and retention in the lung of DCs that can activate naïve CD4(+) T cells in situ. PMID:18039834

Anis, Mursalin M; Fulton, Scott A; Reba, Scott M; Liu, Yi; Harding, Clifford V; Boom, W Henry

2008-02-01

44

Modern laboratory diagnosis of mycobacterial infections  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This review summarises recent advances made in microscopic techniques (fluorescence and peptide nucleic acids) and culture techniques (solid, liquid, radiometric, and non-radiometric systems) and in the development of rapid methods for the identification of mycobacterial cultures (high performance liquid chromatography, thin layer chromatography, RNA sequencing, and polymerase chain reaction restriction enzyme assays). The role of molecular amplification systems in identifying Mycobacterium t...

Watterson, S.; Drobniewski, F.

2000-01-01

45

Mycobacterial infections in solid organ transplant recipients.  

Science.gov (United States)

Mycobacterial infections represent a growing challenge for solid organ transplant recipients (SOT). The adverse effects of tuberculosis (TB) therapy present a major difficulty, due to the interactions with immunosuppressive drugs and direct drug toxicity. While TB may be donor-transmitted or community-acquired, it usually develops at a latent infection site in the recipient. Pre-transplant prevention efforts will improve transplant outcomes and avoid the complications associated with post-transplant diagnosis and treatment. The present review and consensus manuscript is based on the updated published information and expert recommendations. The current data about epidemiology, diagnosis, new regimens for the treatment of latent TB infection (LTBI), the experience with rifamycins for the treatment of active TB in the post-transplant period and the experience with isoniazid for LTBI in the liver transplant population, are also reviewed. We attempt to provide useful recommendations for each transplant period and problem concerning mycobacterial infections in SOT recipients. PMID:24707957

Meije, Y; Piersimoni, C; Torre-Cisneros, J; Dilektasli, A G; Aguado, J M

2014-09-01

46

Detection of mycobacterial antigens in leprosy serum immune complex.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The antigens from immune complexes of sera from patients with mycobacterial diseases were released by sodium dodecyl sulfate. The antigenic activity of the released proteins was tested by agar gel diffusion and immunoelectrophoresis. This simple method provided direct evidence for the presence of mycobacterial antigens in the immune complexes of sera from patients with leprosy and tuberculosis.

1986-01-01

47

Computational genomics-proteomics and Phylogeny analysis of twenty one mycobacterial genomes (Tuberculosis & non Tuberculosis strains  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The genus Mycobacterium comprises different species, among them the most contagious and infectious bacteria. The members of the complex Mycobacterium tuberculosis are the most virulent microorganisms that have killed human and other mammals since millennia. Additionally, with the many different mycobacterial sequences available, there is a crucial need for the visualization and the simplification of their data. In this present study, we aim to highlight a comparative genome, proteome and phylogeny analysis between twenty-one mycobacterial (Tuberculosis and non tuberculosis strains using a set of computational and bioinformatics tools (Pan and Core genome plotting, BLAST matrix and phylogeny analysis. Results Considerably the result of pan and core genome Plotting demonstrated that less than 1250 Mycobacterium gene families are conserved across all species, and a total set of about 20,000 gene families within the Mycobacterium pan-genome of twenty one mycobacterial genomes. Viewing the BLAST matrix a high similarity was found among the species of the complex Mycobacterium tuberculosis and less conservation is found with other slow growing pathogenic mycobacteria. Phylogeny analysis based on both protein conservation, as well as rRNA clearly resolve known relationships between slow growing mycobacteria. Conclusion Mycobacteria include important pathogenic species for human and animals and the Mycobacterium tuberculosis complex is the most cause of death of the humankind. The comparative genome analysis could provide a new insight for better controlling and preventing these diseases.

Zakham Fathiah

2012-08-01

48

Mycobacterial disease in renal allograft recipients  

Directory of Open Access Journals (Sweden)

Full Text Available Implication for health policy/practice/research/medical education:Solid organ transplant recipients have impaired cell-mediated immunity, and are at increased risk of mycobacterial infection. Mycobacterium tuberculosis infection (TB has a high mortality rate among this population. The diagnosis of tuberculosis in solid organ transplant recipients is a big challenge and needs rapid and accurate modalities. These patients have 3.8 time greater risk of developing extra-pulmonary TB than general population. High index of suspicion and applying with invasive diagnostic procedure are needed for diagnosis of TB in renal transplanted patients.

Ardalan Mohammad-Reza

2013-06-01

49

Proteome-wide identification of mycobacterial pupylation targets  

Science.gov (United States)

Mycobacteria use a unique system for covalently modifying proteins based on the conjugation of a small protein, referred to as prokaryotic ubiquitin-like protein (PUP). In this study, we report a proteome-wide analysis of endogenous pupylation targets in the model organism Mycobacterium smegmatis. On affinity capture, a total of 243 candidate pupylation targets were identified by two complementary proteomics approaches. For 41 of these protein targets, direct evidence for a total of 48 lysine-mediated pupylation acceptor sites was obtained by collision-induced dissociation spectra. For the majority of these pupylation targets (38 of 41), orthologous genes are found in the M. tuberculosis genome. Interestingly, approximately half of these proteins are involved in intermediary metabolism and respiration pathways. A considerable fraction of the remaining targets are involved in lipid metabolism, information pathways, and virulence, detoxification and adaptation. Approximately one-third of the genes encoding these targets are located in seven gene clusters, indicating functional linkages of mycobacterial pupylation targets. A comparison of the pupylome under different cell culture conditions indicates that substrate targeting for pupylation is rather dynamic. PMID:20631680

Poulsen, Christian; Akhter, Yusuf; Jeon, Amy Hye-Won; Schmitt-Ulms, Gerold; Meyer, Helmut E; Stefanski, Anja; Stuhler, Kai; Wilmanns, Matthias; Song, Young-Hwa

2010-01-01

50

Tetrahydrolipstatin Inhibition, Functional Analyses, and Three-dimensional Structure of a Lipase Essential for Mycobacterial Viability  

Energy Technology Data Exchange (ETDEWEB)

The highly complex and unique mycobacterial cell wall is critical to the survival of Mycobacteria in host cells. However, the biosynthetic pathways responsible for its synthesis are, in general, incompletely characterized. Rv3802c from Mycobacterium tuberculosis is a partially characterized phospholipase/thioesterase encoded within a genetic cluster dedicated to the synthesis of core structures of the mycobacterial cell wall, including mycolic acids and arabinogalactan. Enzymatic assays performed with purified recombinant proteins Rv3802c and its close homologs from Mycobacterium smegmatis (MSMEG{_}6394) and Corynebacterium glutamicum (NCgl2775) show that they all have significant lipase activities that are inhibited by tetrahydrolipstatin, an anti-obesity drug that coincidently inhibits mycobacterial cell wall biosynthesis. The crystal structure of MSMEG{_}6394, solved to 2.9 {angstrom} resolution, revealed an {alpha}/{beta} hydrolase fold and a catalytic triad typically present in esterases and lipases. Furthermore, we demonstrate direct evidence of gene essentiality in M. smegmatis and show the structural consequences of loss of MSMEG{_}6394 function on the cellular integrity of the organism. These findings, combined with the predicted essentiality of Rv3802c in M. tuberculosis, indicate that the Rv3802c family performs a fundamental and indispensable lipase-associated function in mycobacteria.

Crellin, Paul K.; Vivian, Julian P.; Scoble, Judith; Chow, Frances M.; West, Nicholas P.; Brammananth, Rajini; Proellocks, Nicholas I.; Shahine, Adam; Le Nours, Jerome; Wilce, Matthew C.J.; Britton, Warwick J.; Coppel, Ross L.; Rossjohn, Jamie; Beddoe, Travis (Monash); (Centenary)

2010-09-17

51

Aaptamines, marine spongean alkaloids, as anti-dormant mycobacterial substances.  

Science.gov (United States)

A new aaptamine class alkaloid, designated 2-methoxy-3-oxoaaptamine (1), together with seven known aaptamines (2-8) were isolated from a marine sponge of Aaptos sp. as anti-mycobacterial substances against active and dormant bacilli. The chemical structure of 1 was determined on the basis of spectroscopic analysis. Compound 1 was anti-mycobacterial against Mycobacterium smegmatis in both active growing and dormancy-inducing hypoxic conditions with a minimum inhibitory concentration (MIC) of 6.25 ?g/ml, and compounds 2, 5, 6, and 7 showed anti-mycobacterial activities under hypoxic condition selectively, with MIC values of 1.5-6.25 ?g/ml. PMID:24414399

Arai, Masayoshi; Han, Chisu; Yamano, Yoshi; Setiawan, Andi; Kobayashi, Motomasa

2014-04-01

52

Imaging of non-tuberculous (atypical) mycobacterial pulmonary infection  

International Nuclear Information System (INIS)

Pulmonary infections due to mycobacterial organisms are increasing in incidence. Non-tuberculous (atypical) mycobacteria (NTM) represent a significant proportion of mycobacterial infections and may prove difficult to diagnose due to their non-specific clinical and radiographic presentations. An increasing volume of radiological data is now available for the more common non-tuberculous mycobacterial infections, and we have summarized the imaging features found in such cases, identifying radiographic features that would favour the diagnosis of a non-tuberculous mycobacterium and that, in some cases, suggest a specific organism. Ellis, S.M. and Hansell, D.M. (2002)

53

Imaging of non-tuberculous (atypical) mycobacterial pulmonary infection  

Energy Technology Data Exchange (ETDEWEB)

Pulmonary infections due to mycobacterial organisms are increasing in incidence. Non-tuberculous (atypical) mycobacteria (NTM) represent a significant proportion of mycobacterial infections and may prove difficult to diagnose due to their non-specific clinical and radiographic presentations. An increasing volume of radiological data is now available for the more common non-tuberculous mycobacterial infections, and we have summarized the imaging features found in such cases, identifying radiographic features that would favour the diagnosis of a non-tuberculous mycobacterium and that, in some cases, suggest a specific organism. Ellis, S.M. and Hansell, D.M. (2002)

Ellis, S.M.; Hansell, D.M

2002-08-01

54

Nontuberculous mycobacterial pulmonary diseases in immunocompetent patients  

International Nuclear Information System (INIS)

Nontuberculous mycobacterial (NTM) infections are an increasingly recognized cause of chronic lung disease in immunocompetent adults, and the M. Avium complex, M. Kansasii, and a rapidly growing mycobacteria such as M. abscessus, M. Fortuitum, and M. Chelonae account for most of the pathogens involved. Because the clinical features of NTM disease are not distinguishable from those of tuberculosis, and NTM are ubiquitous in the environment, diagnosis requires that the bacilli are isolated and identified. NTM diseases have been difficult to treat, though since the introduction of new macrolides, the outcome for patients with some NTM diseases has improved significantly. For correct diagnosis and the successful treatment of NTM pulmonary disease, a knowledge of the full spectrum of clinical and radiological findings is important

55

Nontuberculous mycobacterial pulmonary diseases in immunocompetent patients  

Energy Technology Data Exchange (ETDEWEB)

Nontuberculous mycobacterial (NTM) infections are an increasingly recognized cause of chronic lung disease in immunocompetent adults, and the M. Avium complex, M. Kansasii, and a rapidly growing mycobacteria such as M. abscessus, M. Fortuitum, and M. Chelonae account for most of the pathogens involved. Because the clinical features of NTM disease are not distinguishable from those of tuberculosis, and NTM are ubiquitous in the environment, diagnosis requires that the bacilli are isolated and identified. NTM diseases have been difficult to treat, though since the introduction of new macrolides, the outcome for patients with some NTM diseases has improved significantly. For correct diagnosis and the successful treatment of NTM pulmonary disease, a knowledge of the full spectrum of clinical and radiological findings is important.

Koh, Won Jung; Kwon, O Jung; Lee, Kyung Soo [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2002-09-01

56

Molecular Characterization of Environmental Non-Tuberculous Mycobacteria Using PCR- RFLP Analysis of 441 Bp Heat Shock Protein 65 Fragments  

Directory of Open Access Journals (Sweden)

Full Text Available Background: Non- Tuberculous Mycobacteria are environmental opportunistic pathogens that can be found in various terrestrial and aquatic habitats. There are an epidemiological links between species isolated in tap water and those isolated from patients. hsp65 gene has more variability in its sequences, compared to the some more conserved genes in NTM, for identification of mycobacteria to species level. In this study, the prevalence of NTM in Isfahan City water samples was determined using culture, biochemical tests and PCR-RFLP analyses of hsp65 gene.Methods: Eighty-five water samples were collected and cultured. The mycobacterial isolates were identified by conventional biochemical tests. A 441 bp fragment of hsp65 genes was amplified and digested by two restriction enzymes, BstEII and HaeII. Digested products were analyzed using polyacrilamid gel electrophoresis (PAGE.Results: 25.9% of the water samples contained different species of NTM. Dominant isolates were M. fortuitum (26.7%, M. chelonae like organism (13.3% and M. mucogenicum (13.3%. Nineteen isolates of Mycobacteria were differentiated using hsp65 genes PCR-RFLP. Three isolates could not be identified at the species level because their RFLP patterns were different from other known PCR-RFLP profiles. There were different hsp65 gene PCR-RFLP profiles produced by digestion with BstEII and HaeIII. Conclusion: This study showed that PCR-RFLP of hsp65 gene in mycobacteria is more reliable method for identification of NTM at the specie level than conventional phenotypic methods (P<0.05. In comparing of RFLP patterns of this study to other investigation, some minor differences were negligible.

H Rezaei-Yazdi

2012-04-01

57

Mycobacterial mutants with defective control of phagosomal acidification  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The pathogenesis of mycobacterial infection is associated with an ability to interfere with maturation of the phagosomal compartment after ingestion by macrophages. Identification of the mycobacterial components that contribute to this phenomenon will allow rational design of novel approaches to the treatment and prevention of tuberculosis. Microarray-based screening of a transposon library was used to identify mutations that influence the fate of Mycobacterium bovis bacille Calmette-Guérin ...

Stewart, Gr; Patel, J.; Robertson, Bd; Rae, A.; Young, Db

2005-01-01

58

Distribution of lactoferrin and 60/65 kDa heat shock protein in normal and inflamed human intestine and liver.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Immunisation against the mycobacterial heat shock protein (hsp-65) has been proposed to lead to production of autoantibodies against human lactoferrin. Such antibodies occur in ulcerative colitis and in primary sclerosing cholangitis. This study analysed the distribution of hsp-65 and lactoferrin in biopsy specimens from patients with inflammatory bowel disease and primary sclerosing cholangitis and studied whether immunisation against mycobacterial hsp-65 resulted in production of antilactof...

Peen, E.; Enestro?m, S.; Skogh, T.

1996-01-01

59

Further studies on the GS element. A novel mycobacterial insertion sequence (IS1612), inserted into an acetylase gene (mpa) in Mycobacterium avium subsp. silvaticum but not in Mycobacterium avium subsp. paratuberculosis.  

Science.gov (United States)

We have recently described the GS element, found in Mycobacterium avium subsp. paratuberculosis (MAP), Mycobacterium avium subsp. silvaticum (MAS) and some isolates of Mycobacterium avium subsp. avium serotype 2 (MAAs2), which contains a set of genes of low GC% content, putatively associated with the biosynthesis, modification and transference of fucose to cell wall glycopeptidolipids. Here we describe a further gene of low GC% content (mpa), within the GS element in MAP. mpa is a putative acetyltransferase with homology to genes directly responsible for host specificity and virulence in Salmonella typhimurium and Shigella flexneri. Unlike other GS genes, strong homologues of mpa have not been found in related species, including Mycobacterium tuberculosis (MTB). In MAP, mpa encodes an ORF of 445aa, however, in MAS and MAAs2 mpa contains a single inserted copy of a novel insertion sequence. This element (IS1612) has two sets of inverted repeats at each terminus and encodes two ORFs with good homologies to transposase and helper proteins of IS21 (E. coli) and IS1415 (R. erythropolis). Sequence comparisons between mpa in MAP and MAS indicate the target site for IS1612 is duplicated on insertion to give a direct repeat at each end of the element. Immediately, downstream of the mpa gene in both MAP and MAS are a group of three genes with good homology to the daunorubicin resistance cluster. This cluster has a high GC% content which suggests a 'border' for the GS element. A short motif present at the beginning of this cluster matches with an inverted repeat of this motif at the beginning of the first gene in the GS element. This encapsulates the whole of this group of low GC% genes in MAP and further suggests its cassette-like nature. Homologues of the GS element in MTB show a marked similarity of organisation, suggesting a parallel role for these genes in both pathogens. PMID:11118730

Bull, T J; Sheridan, J M; Martin, H; Sumar, N; Tizard, M; Hermon-Taylor, J

2000-12-20

60

Germline but macrophage-tropic CYBB mutations in kindreds with X-linked predisposition to tuberculous mycobacterial diseases  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Germline mutations in the human CYBB gene, encoding the gp91phox subunit of the phagocyte NADPH oxidase, impair the respiratory burst of phagocytes and result in X-linked chronic granulomatous disease. We report two kindreds in which otherwise healthy male adults show X-linked recessive Mendelian susceptibility to mycobacterial diseases. These patients harbor mutations in CYBB that profoundly reduce the respiratory burst in monocyte-derived macrophages, but not in monocyte...

2011-01-01

 
 
 
 
61

Clinical agreement in pulmonary nontuberculous mycobacterial disease  

Directory of Open Access Journals (Sweden)

Full Text Available Peter J Nolan Department of Internal Medicine, Toowoomba General Hospital, Toowoomba, Queensland, Australia Purpose: To consider the clinical agreement among respiratory and infectious disease physicians, working in a tertiary chest diseases center serving a population with a low incidence of pulmonary tuberculosis (<3/100,000/year, in the assessment of cases of pulmonary nontuberculous mycobacterial (NTM lung disease. Method: A series of previously notified cases of NTM disease was abstracted and anonymously presented to a cohort of seven respiratory and infectious disease physicians. Their individual decisions to notify, treat, and follow the cases was evaluated and compared using the intraclass correlation coefficient. Results: A wide range was demonstrated in the diagnostic and management decision triage of each case by the physicians participating in the study. Clinical agreement on the likelihood of disease was limited, with an intraclass correlation coefficient of 0.394. Indication to notify the case to the state registry was linked to the clinical intent to initiate a treatment program. Conclusion: There appears to be limited agreement on the clinical significance of NTM isolates from pulmonary specimens among this cohort of experienced clinicians. If this trend is generalizable to a wider population of respiratory and infectious disease physicians, the number of notified and treated cases of disease is likely to be an underestimate of the true burden of disease in the general population. Keywords: diagnostic certainty, Kappa index, intraclass correlation coefficient, lung disease

Nolan PJ

2013-11-01

62

Inhibitors Selective for Mycobacterial Versus Human Proteasomes  

Energy Technology Data Exchange (ETDEWEB)

Many anti-infectives inhibit the synthesis of bacterial proteins, but none selectively inhibits their degradation. Most anti-infectives kill replicating pathogens, but few preferentially kill pathogens that have been forced into a non-replicating state by conditions in the host. To explore these alternative approaches we sought selective inhibitors of the proteasome of Mycobacterium tuberculosis. Given that the proteasome structure is extensively conserved, it is not surprising that inhibitors of all chemical classes tested have blocked both eukaryotic and prokaryotic proteasomes, and no inhibitor has proved substantially more potent on proteasomes of pathogens than of their hosts. Here we show that certain oxathiazol-2-one compounds kill non-replicating M.?tuberculosis and act as selective suicide-substrate inhibitors of the M.?tuberculosis proteasome by cyclocarbonylating its active site threonine. Major conformational changes protect the inhibitor-enzyme intermediate from hydrolysis, allowing formation of an oxazolidin-2-one and preventing regeneration of active protease. Residues outside the active site whose hydrogen bonds stabilize the critical loop before and after it moves are extensively non-conserved. This may account for the ability of oxathiazol-2-one compounds to inhibit the mycobacterial proteasome potently and irreversibly while largely sparing the human homologue.

Lin, G.; Li, D; Sorio de Carvalho, L; Deng, H; Tao, H; Vogt, G; Wu, K; Schneider, J; Chidawanyika, T; et. al.

2009-01-01

63

Effects of mycobacterial infection on proliferation of hematopoietic precursor cells.  

Science.gov (United States)

Bacterial infection can affect hematopoietic precursor cells in bone marrow, because the infected tissues produce various cytokines and chemokines. Little is known about hematopoietic precursor cells, including hematopoietic stem cells and their progenitors, during mycobacterial infection. Here, we showed that mycobacterial infections result in the expansion of not only the lin-c-kit+sca-1+ (LKS+) cell population, but also granulocyte-monocyte progenitor cells in a chronic murine tuberculosis model. Interestingly, stimulation of LKS+ cells with attenuated Mycobacterium tuberculosis H37Ra culture filtrate (RaCF) was significantly stronger than that by virulent H37Rv culture filtrate (RvCF). Lower TNF-? and IL-6 levels were observed in RvCF-stimulated bone marrow cells. Neutralization of TNF-? or IL-6 in RaCF-stimulated bone marrow cells markedly suppressed LKS+ cell clonal expansion. Additionally, numbers of LKS+ cells were lower in TLR2(-/-) and MyD88(-/-) mice after mycobacterial infection. Taken together, LKS+ cell proliferation related to mycobacterial virulence may be related to the secretion of TNF-? and IL-6 associated with TLR signaling. Expansion of hematopoietic progenitor cells may, therefore, play an important role during mycobacterial infection. PMID:21864704

Choi, Hong-Hee; Kim, Kwang-Kyu; Kim, Kwang Dong; Kim, Hwa-Jung; Jo, Eun-Kyeong; Song, Chang-Hwa

2011-12-01

64

Characterization of mycobacterial UDP-N-acetylglucosamine enolpyruvyle transferase (MurA).  

Science.gov (United States)

The mycobacterial peptidoglycan has structure and biosynthetic pathways to similar those of other bacteria. UDP-N-acetylglucosamine enolpyruvyle transferase (MurA) catalyzes the first reaction in the biosynthesis of peptidoglycan. The MurA enzyme has been identified from various bacterial species, but the in-depth biochemical properties of mycobacterial MurA have not been characterized. In this study, both Mycobacterium tuberculosis MurA protein and Mycobacterium smegmatis MurA protein were overexpressed in Escherichia coli and purified by affinity chromatography. MurA activity was detected by HPLC. A colorimetric assay of MurA activity was also developed and the kinetic properties of Mtb MurA and Msm MurA were determined using this colorimetric assay. A conditional murA gene knockout strain was constructed by DNA homologous recombination. The disruption of murA in the genome of M. smegmatis led to loss of viability at a non-permissive temperature. Drastic morphological and structural alterations in the M. smegmatis murA knockout strain were observed by scanning electron microscopy and transmission electron microscopy. These results demonstrated that murA was an essential gene for growth of M. smegmatis. Therefore, MurA is a potential target for developing new anti-tuberculosis drugs. PMID:24463011

Xu, Liming; Wu, Dongting; Liu, Liang; Zheng, Qi; Song, Yu; Ye, Li; Sha, Shanshan; Kang, Jian; Xin, Yi; Ma, Yufang

2014-01-01

65

Comparative genomic analysis of Mycobacterium iranicum UM_TJL against representative mycobacterial species suggests its environmental origin.  

Science.gov (United States)

Mycobacterium iranicum is a newly reported mycobacterial species. We present the first comparative study of M. iranicum UM_TJL and other mycobacteria. We found M. iranicum to have a close genetic association with environmental mycobacteria infrequently associated with human infections. Nonetheless, UM_TJL is also equipped with many virulence genes (some of which appear to be the consequence of transduction-related gene transfer) that have been identified in established human pathogens. Taken all together, our data suggest that M. iranicum is an environmental bacterium adapted for pathogenicity in the human host. This comparative study provides important clues and forms the basis for future functional studies on this mycobacterium. PMID:25417557

Tan, Joon Liang; Ngeow, Yun Fong; Wee, Wei Yee; Wong, Guat Jah; Ng, Hien Fuh; Choo, Siew Woh

2014-01-01

66

Role for mycobacterial infection in pathogenesis of primary biliary cirrhosis?  

Directory of Open Access Journals (Sweden)

Full Text Available Primary biliary cirrhosis (PBC is a progressive cholestatic liver disease characterized by the immune-mediated destruction of biliary epithelial cells in small intrahepatic bile ducts. The disease is characterized by circulating antimitochondrial antibodies (AMAs as well as disease-specific antinuclear antibodies, cholestatic liver function tests, and characteristic histological features, including granulomas. A variety of organisms are involved in granuloma formation, of which mycobacteria are the most commonly associated. This has led to the hypothesis that mycobacteria may be involved in the pathogenesis of PBC, along with other infectious agents. Additionally, AMAs are found in a subgroup of patients with mycobacterial infections, such as leprosy and pulmonary tuberculosis. Antibodies against species-specific mycobacterial proteins have been reported in patients with PBC, but it is not clear whether these antibodies are specific for the disease. In addition, data in support of the involvement of the role of molecular mimicry between mycobacterial and human mitochondrial antigens as triggers of cross-reactive immune responses leading to the loss of immunological tolerance, and the induction of pathological features have been published. Thus, antibodies against mycobacterial heat shock protein appear to cross-recognize AMA-specific autoantigens, but it is not clear whether these autoantibodies are mycobacterium-species-specific, and whether they are pathogenic or incidental. The view that mycobacteria are infectious triggers of PBC is intriguing, but the data provided so far are not conclusive.

Daniel Smyk

2012-01-01

67

Comparative analysis of mycobacterial NADH pyrophosphatase isoforms reveals a novel mechanism for isoniazid and ethionamide inactivation.  

Science.gov (United States)

NADH pyrophosphatase (NudC) catalyses the hydrolysis of NAD(H) to AMP and NMN(H) [nicotinamide mononucleotide (reduced form)]. NudC multiple sequence alignment reveals that homologues from most Mycobacterium tuberculosis isolates, but not other mycobacterial species, have a polymorphism at the highly conserved residue 237. To elucidate the functional significance of this polymorphism, comparative analyses were performed using representative NudC isoforms from M. tuberculosis H37Rv (NudC(Rv)) and M. bovis BCG (NudC(BCG)). Biochemical analysis showed that the P237Q polymorphism prevents dimer formation, and results in a loss of enzymatic activity. Importantly, NudC(BCG) was found to degrade the active forms of isoniazid (INH), INH-NAD and ethionamide (ETH), ETH-NAD. Consequently, overexpression of NudC(BCG) in Mycobacterium smegmatis mc(2)155 and M. bovis BCG resulted in a high level of resistance to both INH and ETH. Further genetic studies showed that deletion of the nudC gene in M. smegmatis mc(2)155 and M. bovis BCG resulted in increased susceptibility to INH and ETH. Moreover, inactivation of NudC in both strains caused a defect in drug tolerance phenotype for both drugs in exposure assays. Taken together, these data suggest that mycobacterial NudC plays an important role in the inactivation of INH and ETH. PMID:22026918

Wang, Xu-De; Gu, Jing; Wang, Ting; Bi, Li-Jun; Zhang, Zhi-Ping; Cui, Zong-Qiang; Wei, Hong-Ping; Deng, Jiao-Yu; Zhang, Xian-En

2011-12-01

68

DNA encoding individual mycobacterial antigens protects mice against tuberculosis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Over the last few years, some of our experiments in which mycobacterial antigens were presented to the immune system as if they were viral antigens have had a significant impact on our understanding of protective immunity against tuberculosis. They have also markedly enhanced the prospects for new v [...] accines. We now know that individual mycobacterial protein antigens can confer protection equal to that from live BCG vaccine in mice. A critical determinant of the outcome of immunization appears to be the degree to which antigen-specific cytotoxic T cells are generated by the immune response. Our most recent studies indicate that DNA vaccination is an effective way to establish long-lasting cytotoxic T cell memory and protection against tuberculosis.

C.L., Silva; V.L.D., Bonato; V.M.F., Lima.

69

DNA encoding individual mycobacterial antigens protects mice against tuberculosis  

Directory of Open Access Journals (Sweden)

Full Text Available Over the last few years, some of our experiments in which mycobacterial antigens were presented to the immune system as if they were viral antigens have had a significant impact on our understanding of protective immunity against tuberculosis. They have also markedly enhanced the prospects for new vaccines. We now know that individual mycobacterial protein antigens can confer protection equal to that from live BCG vaccine in mice. A critical determinant of the outcome of immunization appears to be the degree to which antigen-specific cytotoxic T cells are generated by the immune response. Our most recent studies indicate that DNA vaccination is an effective way to establish long-lasting cytotoxic T cell memory and protection against tuberculosis.

Silva C.L.

1999-01-01

70

Targeting the mycobacterial envelope for tuberculosis drug development.  

Science.gov (United States)

The bacterium that causes tuberculosis, Mycobacterium tuberculosis, possesses a rather unique outer membrane composed largely of lipids that possess long-chain and branched fatty acids, called mycolic acids. These lipids form a permeability barrier that prevents entry of many environmental solutes, thereby making these bacteria acid-fast and able to survive extremely hostile surroundings. Antitubercular drugs must penetrate this layer to reach their target. This review highlights drug development efforts that have added to the slowly growing tuberculosis drug pipeline, identified new enzyme activities to target with drugs and increased the understanding of important biosynthetic pathways for mycobacterial outer membrane and cell wall core assembly. In addition, a portion of this review looks at discovery efforts aimed at weakening this barrier to decrease mycobacterial virulence, decrease fitness in the host or enhance the efficacy of the current drug repertoire by disrupting the permeability barrier. PMID:23106277

Favrot, Lorenza; Ronning, Donald R

2012-09-01

71

In vitro reconstitution of Mycobacterial ergothioneine biosynthesis.  

Science.gov (United States)

Ergothioneine is a histidine-derived thiol of bacterial and fungal origin that has also been isolated from animal and human tissue. Recent findings point to critical functions of ergothioneine in human physiology, but its role in microbial life is poorly understood. This report describes the identification of the ergothioneine biosynthetic gene cluster from mycobacteria and in vitro reconstitution of this process using recombinant proteins from Mycobacterium smegmatis. The key reactions are catalyzed by a methyltransferase that transfers three methyl groups to the alpha-amino moiety of histidine and an iron(II)-dependent enzyme that catalyzes oxidative sulfurization of trimethylhistidine. A search for homologous genes indicated that ergothioneine production is a frequent trait among fungi, actinobacteria, and cyanobacteria but also occurs in numerous bacteroidetes and proteobacteria. PMID:20420449

Seebeck, Florian P

2010-05-19

72

Polyphenolic acetates : A newer anti-Mycobacterial therapeutic option  

Directory of Open Access Journals (Sweden)

Full Text Available The objective of our research project was screening of various highly specific substrates of Acetoxy Drug: Protein Transacytylase (M.TAase for antimycobacterial activity. Mycobacterial culture was done in Middlebrook’s 7H9 media. Protein purification (Mycobacterial Tranacetylase, M.TAase was done by ion exchange chromatography and its demonstration was done on SDS- polyacrylamide gel electrophoresis (SDS-PAGE and western blot. Middlebrook’s 7H9 broth was procured from Becton Dickinson. CM-Sepharose, DEAE-Sepharose and Q-Sephharose were purchased from Amersham Pharmacia. Anti acetyl lysine polyclonal antibody was purchased from Cell Signaling. The Middlebrook 7H9 medium was used for M. smegmatis culture. The media was prepared according to the manufacturer’s instructions. The various Polyphenol acetate compounds were tested for their antimycobacterial activities. Minimal inhibitory concentrations (MIC were calculated by Alamar blue dye assay method. The GST protein was used as a receptor protein and purified Mycobacterial Glutamine Synthetase (GS as TAase for acetylation by DAMC. To demonstrate the TAase catalyzed acetylation of GST by DAMC, purified M.TAase (GS was preincubated with GST and DAMC followed by western blot using anti acetyl lysine antibody, which avidly react with the acetylated proteins. The growth pattern of M. smegmatis was diminished under the influence of various polyphenolic acetates (PA tested for their anti-mycobacterial activity. DAMC and DAMC-5-carboxylic acid was found to have MIC of 40?g/ml whereas DAMC-6-carboxylic acid was reported to have MIC value of 35?g/ml and for ellagic acid tetra acetate (EATA it was 60?g/ml. Previous work in our lab has led to discovery of a novel enzyme acetoxy drug: protein transacetylase (TAase, catalyzing transfer of acetyl group from various polyphenolic peracetate (PA to certain receptor proteins such as cytochromes P-450, NADPH cytochrome reductase, nitric oxide synthase (NOS has been established in various eukaryotic as well as prokaryotic sources. PA(s irreversible inhibitors of mammalian CYP linked MFO, possibly due to modification of cytochrome p- 450 by acetylation in a reaction catalysed by M.TAase (GS utilizing PA(s as a donor of acetyl groups. Accordingly, it was hypothesized that the CYP51 of mycobacteria involved in the cell wall sterol synthesis could possibly be modified by our PA(s through the novel unknown action of GS as transacetylase leading to the death of mycobacterial cell by way of acetylation catalyzed by acetoxy drug: protein transacetylase (M.TAase or GS.

Santram

2014-01-01

73

Assembly and proteolytic processing of mycobacterial ClpP1 and ClpP2  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Caseinolytic proteases (ClpPs are barrel-shaped self-compartmentalized peptidases involved in eliminating damaged or short-lived regulatory proteins. The Mycobacterium tuberculosis (MTB genome contains two genes coding for putative ClpPs, ClpP1 and ClpP2 respectively, that are likely to play a role in the virulence of the bacterium. Results We report the first biochemical characterization of ClpP1 and ClpP2 peptidases from MTB. Both proteins were produced and purified in Escherichia coli. Use of fluorogenic model peptides of diverse specificities failed to show peptidase activity with recombinant mycobacterial ClpP1 or ClpP2. However, we found that ClpP1 had a proteolytic activity responsible for its own cleavage after the Arg8 residue and cleavage of ClpP2 after the Ala12 residue. In addition, we showed that the absence of any peptidase activity toward model peptides was not due to an obstruction of the entry pore by the N-terminal flexible extremity of the proteins, nor to an absolute requirement for the ClpX or ClpC ATPase complex. Finally, we also found that removing the putative propeptides of ClpP1 and ClpP2 did not result in cleavage of model peptides. We have also shown that recombinant ClpP1 and ClpP2 do not assemble in the conventional functional tetradecameric form but in lower order oligomeric species ranging from monomers to heptamers. The concomitant presence of both ClpP1 and ClpP2 did not result in tetradecameric assembly. Deleting the amino-terminal extremity of ClpP1 and ClpP2 (the putative propeptide or entry gate promoted the assembly in higher order oligomeric species, suggesting that the flexible N-terminal extremity of mycobacterial ClpPs participated in the destabilization of interaction between heptamers. Conclusion Despite the conservation of a Ser protease catalytic triad in their primary sequences, mycobacterial ClpP1 and ClpP2 do not have conventional peptidase activity toward peptide models and display an unusual mechanism of self-assembly. Therefore, the mechanism underlying their peptidase and proteolytic activities might differ from that of other ClpP proteolytic complexes.

Benaroudj Nadia

2011-12-01

74

Nontuberculous Mycobacterial Tenosynovitis in the Hand: Two Case Reports with the MR Imaging Findings  

International Nuclear Information System (INIS)

Nontuberculous mycobacterial infections can cause destructive tenosynovitis of the hand. We report on and discuss the clinical course and distinctive radiologic findings of two patients with hand tenosynovitis secondary to M. marinum and intracellulare infection, which are different from those of the nontuberculous mycobacterial infections reported in the previous literature.

75

Nontuberculous Mycobacterial Tenosynovitis in the Hand: Two Case Reports with the MR Imaging Findings  

Energy Technology Data Exchange (ETDEWEB)

Nontuberculous mycobacterial infections can cause destructive tenosynovitis of the hand. We report on and discuss the clinical course and distinctive radiologic findings of two patients with hand tenosynovitis secondary to M. marinum and intracellulare infection, which are different from those of the nontuberculous mycobacterial infections reported in the previous literature.

Yoon, Hyun Jung; Kwon, Jong Won; Yoon, Young Cheol; Choi, Sang Hee [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2011-11-15

76

Integrative immunoinformatics for Mycobacterial diseases in R platform.  

Science.gov (United States)

The sequencing of genomes of the pathogenic Mycobacterial species causing pulmonary and extrapulmonary tuberculosis, leprosy and other atypical mycobacterial infections, offer immense opportunities for discovering new therapeutics and identifying new vaccine candidates. Enhanced RV, which uses additional algorithms to Reverse Vaccinology (RV), has increased potential to reduce likelihood of undesirable features including allergenicity and immune cross reactivity to host. The starting point for MycobacRV database construction includes collection of known vaccine candidates and a set of predicted vaccine candidates identified from the whole genome sequences of 22 mycobacterium species and strains pathogenic to human and one non-pathogenic Mycobacterium tuberculosis H37Ra strain. These predicted vaccine candidates are the adhesins and adhesin-like proteins obtained using SPAAN at Pad > 0.6 and screening for putative extracellular or surface localization characteristics using PSORTb v.3.0 at very stringent cutoff. Subsequently, these protein sequences were analyzed through 21 publicly available algorithms to obtain Orthologs, Paralogs, BetaWrap Motifs, Transmembrane Domains, Signal Peptides, Conserved Domains, and similarity to human proteins, T cell epitopes, B cell epitopes, Discotopes and potential Allergens predictions. The Enhanced RV information was analysed in R platform through scripts following well structured decision trees to derive a set of nonredundant 233 most probable vaccine candidates. Additionally, the degree of conservation of potential epitopes across all orthologs has been obtained with reference to the M. tuberculosis H37Rv strain, the most commonly used strain in M. tuberculosis studies. Utilities for the vaccine candidate search and analysis of epitope conservation across the orthologs with reference to M. tuberculosis H37Rv strain are available in the mycobacrvR package in R platform accessible from the "Download" tab of MycobacRV webserver. MycobacRV an immunoinformatics database of known and predicted mycobacterial vaccine candidates has been developed and is freely available at http://mycobacteriarv.igib.res.in. PMID:24592289

Chaudhuri, Rupanjali; Kulshreshtha, Deepika; Raghunandanan, Muthukurussi Varieth; Ramachandran, Srinivasan

2014-03-01

77

Identification and characterization of a mycobacterial (2R,3R)-2,3-butanediol dehydrogenase.  

Science.gov (United States)

Bacterial strain B-009, capable of using racemic 1,2-propanediol (PD), was identified as a rapid-growing member of the genus Mycobacterium. The strain is phylogenetically related to M. gilvum, but has slightly different physiological characteristics. An NAD(+)-dependent enantioselective alcohol dehydrogenase, which acts on R-PD, was purified from the strain. The enzyme was a homodimer of a peptide coded by a 1047-bp gene (mbd1). A highly conserved sequence for medium-chain dehydrogenase/reductases with a preference for secondary alcohols was found in the gene. Hydroxyacetone was produced from R-PD by an enzymatic reaction, indicating that position 2 of the substrate was oxidized. The enzyme activity was highest for (2R,3R)-2,3-butanediol (R,R-BD), enabling the enzyme to be identified as (2R,3R)-2,3-butanediol dehydrogenase (R,R-BD-DH). A homology search revealed M. gilvum, M. vanbaalenii, and M. semegmatis to have ORFs similar to mbd1, suggesting the widespread distribution of genes encoding R,R-BD-DH among mycobacterial strains. PMID:22146728

Takeda, Minoru; Muranushi, Takahiro; Inagaki, Sawako; Nakao, Takuya; Motomatsu, Shigekazu; Suzuki, Ichiro; Koizumi, Jun-ichi

2011-01-01

78

The mycobacterial DNA-binding protein 1 (MDP1 from Mycobacterium bovis BCG influences various growth characteristics  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Pathogenic mycobacteria such as M. tuberculosis, M. bovis or M. leprae are characterised by their extremely slow growth rate which plays an important role in mycobacterial virulence and eradication of the bacteria. Various limiting factors influence the generation time of mycobacteria, and the mycobacterial DNA-binding protein 1 (MDP1 has also been implicated in growth regulation. Our strategy to investigate the role of MDP1 in mycobacterial growth consisted in the generation and characterisation of a M. bovis BCG derivative expressing a MDP1-antisense gene. Results The expression rate of the MDP1 protein in the recombinant M. bovis BCG containing the MDP1-antisense plasmid was reduced by about 50% compared to the reference strain M. bovis BCG containing the empty vector. In comparison to this reference strain, the recombinant M. bovis BCG grew faster in broth culture and reached higher cell masses in stationary phase. Likewise its intracellular growth in mouse and human macrophages was ameliorated. Bacterial clumping in broth culture was reduced by the antisense plasmid. The antisense plasmid increased the susceptibility of the bacteria towards Ampicillin. 2-D protein gels of bacteria maintained under oxygen-poor conditions demonstrated a reduction in the number and the intensity of many protein spots in the antisense strain compared to the reference strain. Conclusion The MDP1 protein has a major impact on various growth characteristics of M. bovis BCG. It plays an important role in virulence-related traits such as aggregate formation and intracellular multiplication. Its impact on the protein expression in a low-oxygen atmosphere indicates a role in the adaptation to the hypoxic conditions present in the granuloma.

Maurischat Sven

2008-06-01

79

Mycobacterial culture of fine needle aspirate - A useful tool in diagnosing tuberculous lymphadenitis  

Directory of Open Access Journals (Sweden)

Full Text Available A prospective study was undertaken on suspected lymph node TB (LNTB patients, to evaluate the diagnostic utility of mycobacterial culture of fine needle aspirate (FNA, in comparison with the cytological examination and acid fast staining. Eighty percent of 157 aspirates studied were positive by cytological examination; 18% by ZN smear and 45% were positive by culture. Twelve aspirates which were negative by cytological features yielded positive mycobacterial cultures; four out of these were from HIV positive patients. Our observations suggest that supplementing FNA cytology with mycobacterial culture would increase the sensitivity of diagnosing LNTB; in addition to giving a highly specific diagnosis.

Kishore Reddy V

2008-01-01

80

Imaging of tuberculous and non-tuberculous mycobacterial infections  

International Nuclear Information System (INIS)

Full text: Both tuberculosis (TB) and non-tuberculous mycobacterial (NTM) infections are increasing in prevalence and radiologists must be aware of the increasing likelihood of encountering these infections. The NTM organisms are often overlooked as potential infecting organisms, diagnosis is often delayed as they tend not to be included in the radiologic differential diagnosis. Clinical and radiological manifestations of pulmonary TB depend on whether the host is naive to the infecting organism (primary TB) or whether there has been reactivation or reexposure (postprimary TB). In immunocompetent patients primary TB tends to be self-limiting, but resolution of the primary lesion is usually slow, and often results in permanent scarring. Postprimary TB lesions (reactivation of a dormant primary infection) tend to be focal, nodular, with a slow progressive course resulting in high morbidity and mortality if not adequately treated. The most common atypical mycobacterial infection is caused by Mycobacterium avium intracellulare complex. Two target groups are mainly encountered in NTM infections: 1) males more than 50 years old with preexisting lung disease presenting constitutional symptoms and 2) elderly women with no preexisting pulmonary disease with less pronounced constitutional symptoms. NTM infection is usually indolent, sometimes remaining stable for a long period; however, without treatment it may progress and ultimately be fatal. CT findings of primary tuberculosis consist of consolidation mainly in middle and lower lobes and lymphadenopathy with hypodense centre and rim enhancement on contrast-enhanced CT. Tree-in bud appearance adjacent to areas of consolidation is consistent with endobronchial spread. Cavitary lesions are less common than in primary.

 
 
 
 
81

Persistent inactivation of macrophage cyclooxygenase-2 in mycobacterial pulmonary inflammation.  

Science.gov (United States)

The induction of cyclooxygenase-2 (COX-2) in tissue macrophages (MØ) increases prostaglandin E(2) (PGE(2)) release, potentially down-regulating granulomatous inflammation. In response to Mycobacteria, local MØ express COX-2, which is either nuclear envelope (NE)-associated or NE-dissociated. Persistent mycobacterial pulmonary inflammation is characterized by alveolar MØ expressing NE-dissociated (inactive) COX-2 without release of PGE(2). In this study, we examined COX-2 in alveolar MØ after intranasal exposure to heat-killed Mycobacterium bovis BCG (HK-BCG). After administration, whole lungs of C57Bl/6 mice were lavaged with saline; COX-2 expression and PGE(2) release by alveolar MØ and tumor necrosis factor (TNF)-alpha and nitric oxide levels in the lung lavage were monitored. Normal alveolar MØ had undetectable levels of COX-2 on Western blots. However, 1 day after intranasal administration, almost all alveolar MØ had phagocytosed HK-BCG and expressed NE-dissociated COX-2 without any increase in the release of PGE(2). At 28 days after intranasal administration, 68% of alveolar MØ still contained both BCG and the NE-dissociated form of COX-2. NE-associated (active) COX-2 was not observed in alveolar MØ. In contrast, 7 days after intraperitoneal injection of HK-BCG, peritoneal MØ containing HK-BCG were no longer detected. At 28 days after intranasal administration, TNF-alpha and nitrite levels in the lung lavage fluid were significantly higher than those in controls. Our results indicate that mycobacterial pulmonary inflammation is associated with suppressed PGE(2) production by alveolar MØ, with expression of COX-2 dissociated from the NE. PMID:19097981

Shinohara, Tsutomu; Pantuso, Traci; Shinohara, Shizuka; Kogiso, Mari; Myrvik, Quentin N; Henriksen, Ruth Ann; Shibata, Yoshimi

2009-08-01

82

Adequate Th2-type response associates with restricted bacterial growth in latent mycobacterial infection of zebrafish.  

Science.gov (United States)

Tuberculosis is still a major health problem worldwide. Currently it is not known what kind of immune responses lead to successful control and clearance of Mycobacterium tuberculosis. This gap in knowledge is reflected by the inability to develop sufficient diagnostic and therapeutic tools to fight tuberculosis. We have used the Mycobacterium marinum infection model in the adult zebrafish and taken advantage of heterogeneity of zebrafish population to dissect the characteristics of adaptive immune responses, some of which are associated with well-controlled latency or bacterial clearance while others with progressive infection. Differences in T cell responses between subpopulations were measured at the transcriptional level. It was discovered that a high total T cell level was usually associated with lower bacterial loads alongside with a T helper 2 (Th2)-type gene expression signature. At late time points, spontaneous reactivation with apparent symptoms was characterized by a low Th2/Th1 marker ratio and a substantial induction of foxp3 reflecting the level of regulatory T cells. Characteristic gata3/tbx21 has potential as a biomarker for the status of mycobacterial disease. PMID:24968056

Hammarén, Milka Marjut; Oksanen, Kaisa Ester; Nisula, Hanna Maria; Luukinen, Bruno Vincent; Pesu, Marko; Rämet, Mika; Parikka, Mataleena

2014-06-01

83

Molecular-based mycobacterial identification in a clinical laboratory setting: a comparison of two methods.  

LENUS (Irish Health Repository)

Many mycobacterial species are pathogenic to humans, with infection occurring worldwide. Infection with Mycobacterium tuberculosis is a well-described global phenomenon, but other mycobacterial species are increasingly shown to be the cause of both pulmonary and extrapulmonary infection and are managed differently from M. tuberculosis infection. Rapid and accurate differentiation of mycobacterial species is, therefore, critical to guide timely and appropriate therapeutic and public health management. This study evaluates two commercially available DNA strip assays, the Genotype Common Mycobacteria (CM) assay (Hain Lifescience, Nehren, Germany) and the Speed-oligo Mycobacteria assay (Vircell, Spain) for their usefulness in a clinical laboratory setting. Both assays were evaluated on 71 clinical mycobacterial isolates, previously identified using Gen-Probe AccuProbe and through a UK mycobacteriology reference laboratory, as well as 29 non-mycobacterial isolates. Concordant results were obtained for 98% of isolates using both assays. The sensitivity was 97% (95% confidence interval [CI]: 93.3-100%) for the CM assay and 98.6% (95% CI: 95.9-100%) for the Speed-oligo assay. Overall, both assays proved to be useful tools for rapid and sensitive mycobacterial species identification, although interpretation of results was easier with the CM assay. Finally, results were available within one day, compared to current identification times which range between seven days and four weeks.

O'Donnell, N

2012-01-01

84

Differentiation and Phylogenetic Relationships in Mycobacterium spp with Special Reference to the RNase P RNA Gene rnpB.  

Science.gov (United States)

The rnpB gene encodes for the RNA subunit of the catalytic ribonuclease RNase P and is present in all bacteria and has both conserved and highly variable sequence regions. Determination of rnpB in 35 Mycobacterium spp. showed species specific sequences for all species except the Mycobacterium tuberculosis complex (four species). High sequence variation was seen in the P3, P15 and P19 regions of suggested secondary structures of the corresponding RNase P RNA molecules. Phylogenetic analysis showed that rnpB gave similar tree topologies as 16S rRNA and hsp65 genes. A combined analysis of the three genes increased the number of nodes with significant support from 10 to 19. The results indicate that rnpB is useful for phylogenetic studies and is a possible target for identification and detection of Mycobacterium spp. PMID:24962595

Herrmann, Björn; Stolt, Pelle; Abdeldaim, Guma; Rubin, Carl-Johan; Kirsebom, Leif A; Thollesson, Mikael

2014-11-01

85

Germline CYBB mutations that selectively affect macrophages in kindreds with X-linked predisposition to tuberculous mycobacterial disease  

Science.gov (United States)

Germline mutations in CYBB, the human gene encoding the gp91phox subunit of the phagocyte NADPH oxidase, impair the respiratory burst of all types of phagocytes and result in X-linked chronic granulomatous disease (CGD). We report here two kindreds in which otherwise healthy male adults developed X-linked recessive Mendelian susceptibility to mycobacterial disease (MSMD) syndromes. These patients had previously unknown mutations in CYBB that resulted in an impaired respiratory burst in monocyte-derived macrophages but not in monocytes or granulocytes. The macrophage-specific functional consequences of the germline mutation resulted from cell-specific impairment in the assembly of the NADPH oxidase. This ‘experiment of nature’ indicates that CYBB is associated with MSMD and demonstrates that the respiratory burst in human macrophages is a crucial mechanism for protective immunity to tuberculous mycobacteria. PMID:21278736

Bustamante, Jacinta; Arias, Andres A; Vogt, Guillaume; Picard, Capucine; Galicia, Lizbeth Blancas; Prando, Carolina; Grant, Audrey V; Marchal, Christophe C; Hubeau, Marjorie; Chapgier, Ariane; de Beaucoudrey, Ludovic; Puel, Anne; Feinberg, Jacqueline; Valinetz, Ethan; Janniere, Lucile; Besse, Celine; Boland, Anne; Brisseau, Jean-Marie; Blanche, Stephane; Lortholary, Olivier; Fieschi, Claire; Emile, Jean-Francois; Boisson-Dupuis, Stephanie; Al-Muhsen, Saleh; Woda, Bruce; Newburger, Peter E; Condino-Neto, Antonio; Dinauer, Mary C; Abel, Laurent; Casanova, Jean-Laurent

2011-01-01

86

Doença pulmonar por Mycobacterium tuberculosis e micobactérias não-tuberculosas entre pacientes recém-diagnosticados como HIV positivos em Moçambique, África / Mycobacterium tuberculosis and nontuberculous mycobacterial isolates among patients with recent HIV infection in Mozambique  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: A micobacteriose é frequentemente diagnosticada entre pacientes infectados pelo HIV. Em Moçambique, onde apenas um pequeno número de pacientes encontra-se sob tratamento anti-retroviral, e a tuberculose tem alta prevalência, existe a necessidade de melhor caracterização destes agentes bact [...] erianos, em nível de espécie, bem como de se caracterizar os padrões de resistência às drogas antituberculosas. MÉTODOS: Em uma coorte de 503 indivíduos HIV positivos suspeitos de tuberculose pulmonar, 320 apresentaram positividade para baciloscopia ou cultura no escarro e no lavado brônquico. RESULTADOS: Bacilos álcool-ácido resistentes foram detectados no escarro em 73% dos casos com cultura positiva. De 277 isolados em cultura, apenas 3 mostraram-se tratar de micobactérias não-tuberculosas: 2 Mycobacterium avium e uma M. simiae. Todos os isolados de M. tuberculosis inicialmente caracterizados através de reação em cadeia de polimerase (RCP) do gene hsp65 foram posteriormente caracterizados como tal através de RCP do gene gyrB. Resistência à isoniazida foi encontrada em 14% dos casos; à rifampicina em 6%; e multirresistência em 5%. Pacientes previamente tratados para tuberculose mostraram tendência a taxas maiores de resistência às drogas de primeira linha. O padrão radiológico mais freqüente encontrado foi o infiltrado intersticial (67%), seguido da presença de linfonodos mediastinais (30%), bronquiectasias (28%), padrão miliar (18%) e cavidades (12%). Os pacientes infectados por micobactérias não-tuberculosas não apresentaram manifestações clínicas distintas das apresentadas pelos outros pacientes. A mediana de linfócitos CD4 entre todos os pacientes foi de 134 células/mm³. CONCLUSÕES: Tuberculose e AIDS em Moçambique estão fortemente associadas, como é de se esperar em países com alta prevalência de tuberculose. Embora as taxas de resistência a drogas sejam altas, o esquema isoniazida-rifampicina continua sendo a escolha apropriada para o início do tratamento. Abstract in english OBJECTIVE: Mycobacteriosis is frequently diagnosed among HIV-infected patients. In Mozambique, where few patients are under antiretroviral therapy and the prevalence of tuberculosis is high, there is need for better characterization of mycobacteria at the species level, as well as for the identifica [...] tion of patterns of resistance to antituberculous drugs. METHODS: We studied a sample of 503 HIV-infected individuals suspected of having pulmonary tuberculosis. Of those 503, 320 tested positive for mycobacteria through sputum smear microscopy or culture of bronchoalveolar lavage fluid. RESULTS: Acid-fast bacilli were observed in the sputum of 73% of the individuals presenting positive cultures. Of 277 isolates tested, only 3 were nontuberculous mycobacteria: 2 were identified as Mycobacterium avium and one was identified as M. simiae. Strains initially characterized as M. tuberculosis complex through polymerase chain reaction restriction analysis (PRA) of the hsp65 gene were later confirmed as such through PRA of the gyrB gene. Among the M. tuberculosis isolates, resistance patterns were as follows: to isoniazid, 14%; to rifampin, 6%; and multidrug resistance, 5%. Previously treated cases showed significantly higher rates of resistance to first-line antituberculous drugs. The most common radiological pattern was interstitial infiltrate (in 67%), followed by mediastinal lymph node enlargement (in 30%), bronchiectasis (in 28%), miliary nodules (in 18%) and cavitation (in 12%). Patients infected with nontuberculous mycobacteria presented clinical profiles indistinguishable from those of other patients. The median CD4 lymphocyte count in this group was 134 cells/mm³. CONCLUSIONS: There is a strong association between tuberculosis and AIDS in Mozambique, as expected in a country with a high prevalence of tuberculosis. Although drug resistance rates are high, the isoniazid-rifampin regimen continues to be the appr

Elizabete Abrantes, Nunes; Eduardo Mello, De Capitani; Elizabete, Coelho; Alessandra Costa, Panunto; Orvalho Augusto, Joaquim; Marcelo de Carvalho, Ramos.

2008-10-01

87

Real-Time Bioluminescence Imaging of Mixed Mycobacterial Infections  

Science.gov (United States)

Molecular analysis of infectious processes in bacteria normally involves construction of isogenic mutants that can then be compared to wild type in an animal model. Pathogenesis and antimicrobial studies are complicated by variability between animals and the need to sacrifice individual animals at specific time points. Live animal imaging allows real-time analysis of infections without the need to sacrifice animals, allowing quantitative data to be collected at multiple time points in all organs simultaneously. However, imaging has not previously allowed simultaneous imaging of both mutant and wild type strains of mycobacteria in the same animal. We address this problem by using both firefly (Photinus pyralis) and click beetle (Pyrophorus plagiophthalamus) red luciferases, which emit distinct bioluminescent spectra, allowing simultaneous imaging of two different mycobacterial strains during infection. We also demonstrate that these same bioluminescence reporters can be used to evaluate therapeutic efficacy in real-time, greatly facilitating our ability to screen novel antibiotics as they are developed. Due to the slow growth rate of mycobacteria, novel imaging technologies are a pressing need, since they can they can impact the rate of development of new therapeutics as well as improving our understanding of virulence mechanisms and the evaluation of novel vaccine candidates. PMID:25265287

Chang, MiHee; Anttonen, Katri P.; Cirillo, Suat L. G.; Francis, Kevin P.; Cirillo, Jeffrey D.

2014-01-01

88

Organization of the mycobacterial cell wall: a nanoscale view.  

Science.gov (United States)

The biosynthesis of the Mycobacterium tuberculosis cell wall is targeted by some of the most powerful antituberculous drugs. To date, the molecular mechanisms by which these antibiotics affect the cell wall characteristics are not well understood. Here, we used atomic force microscopy - in three different modes - to probe the nanoscale surface properties of live mycobacteria and their modifications upon incubation with four antimycobacterial drugs: isoniazid, ethionamide, ethambutol, and streptomycine. Topographic imaging, combined with quantitative surface roughness analysis, demonstrated that all drugs induce a substantial increase of surface roughness to an extent that correlates with the localization of the target (i.e., synthesis of mycolic acids, arabinogalactans, or proteins). Chemical force microscopy with hydrophobic tips revealed that the structural alterations induced by isoniazid and ethambutol were correlated with a dramatic decrease of cell surface hydrophobicity, reflecting the removal of the outermost mycolic acid layer. Consistent with this finding, tapping mode imaging, combined with immunogold labeling, showed that the two drugs lead to the massive exposure of hydrophilic lipoarabinomannans at the surface. Taken together, these structural, chemical, and immunological data provide novel insight into the action mode of antimycobacterial drugs, as well as into the spatial organization of the mycobacterial cell wall. PMID:18043940

Alsteens, David; Verbelen, Claire; Dague, Etienne; Raze, Dominique; Baulard, Alain R; Dufrêne, Yves F

2008-04-01

89

Inhibition of Mycobacterial Alanine Racemase Activity and Growth by Thiadiazolidinones  

Science.gov (United States)

The genus Mycobacterium includes non-pathogenic species such as M. smegmatis, and pathogenic species such as M. tuberculosis, the causative agent of tuberculosis (TB). Treatment of TB requires a lengthy regimen of several antibiotics, whose effectiveness has been compromised by the emergence of resistant strains. New antibiotics that can shorten the treatment course and those that have not been compromised by bacterial resistance are needed. In this study, we report that thiadiazolidinones, a relatively little-studied heterocyclic class, inhibit the activity of mycobacterial alanine racemase, an essential enzyme that converts L-alanine to D-alanine for peptidoglycan synthesis. Twelve members of the thiadiazolidinone family were evaluated for inhibition of M. tuberculosis and M. smegmatis alanine racemase activity and bacterial growth. Thiadiazolidinones inhibited M. tuberculosis and M. smegmatis alanine racemases to different extents with 50% inhibitory concentrations (IC50) ranging from 150 µM, respectively. The compounds also inhibited the growth of these bacteria, including multidrug resistant strains of M. tuberculosis. The minimal inhibitory concentrations (MIC) for drug-susceptible M. tuberculosis and M. smegmatis ranged from 6.25 µg/ml to 100 µg/ml, and from 1.56 to 6.25 µg/ml for drug-resistant M. tuberculosis. The in vitro activities of thiadiazolidinones suggest that this family of compounds might represent starting points for medicinal chemistry efforts aimed at developing novel antimycobacterial agents. PMID:23680030

Lee, Yashang; Mootien, Sara; Shoen, Carolyn; Destefano, Michelle; Cirillo, Pier; Asojo, Oluwatoyin A.; Yeung, Kacheong R.; Ledizet, Michel; Cynamon, Michael H.; Aristoff, Paul A.; Koski, Raymond A.; Kaplan, Paul A.; Anthony, Karen G.

2013-01-01

90

Nontuberculous mycobacterial infections among patients suspected of pulmonary tuberculosis.  

Science.gov (United States)

The purpose of this study was to present a retrospective analysis of the frequency of nontuberculous mycobacteria (NTM)-related pulmonary infections among the AFB-positive and/or culture-positive patients in the Warsaw region who were suspected of tuberculosis (TB) and hospitalized in the university hospital between 1999 and 2005. All the AFB-positive pulmonary samples were examined with a molecular method using the Amplicor MTB test (Roche) for detection of Mycobacterium tuberculosis complex, and all mycobacterial isolates were speciated by high performance liquid chromatography (HPLC) analysis of mycolic acids. Patients who met clinical, radiological, and bacteriological criteria of mycobacteriosis were classified according to the American Thoracic Society (ATS) guidelines for diagnosis of NTM related disease. Among the 445 smear-positive or/and culture-positive patients, 142 subjects (31.9%) were found to be infected with M. tuberculosis. Among 303 non-TB patients, mycobacteriosis was found in 27 (8.9%) subjects. The frequency of NTM-related lung disease as compared to the bacteriologically-confirmed lung TB was estimated at 1:5. The rapid, precise methods of NTM speciation are necessary for progress in diagnostics of NTM related diseases. PMID:19219472

Grubek-Jaworska, H; Walkiewicz, R; Safianowska, A; Nowacka-Mazurek, M; Krenke, R; Przyby?owski, T; Chazan, R

2009-07-01

91

Anti-mycobacterial activity of 1,3-diaryltriazenes.  

Science.gov (United States)

The rapid generation and spread of the drug resistant tuberculosis has led to an ongoing demand for novel compounds for therapeutic use. Identification and study of compounds with the ability to inhibit Mycobacterium tuberculosis is of paramount importance. For this reason, a library of substituted 1,3-diaryltriazenes based on the acting component of the anti-trypanosomal drug, diminazene aceturate was created and evaluated for its potential as anti-tubercular agent. Several compounds were identified with sub-micro molar inhibitory concentrations against M. tuberculosis and other clinically relevant mycobacterial species such as Mycobacterium bovis, Mycobacterium avium and Mycobacterium ulcerans. Although the library of the compounds showed a considerable acute cytotoxicity, a genotoxicity could not be observed. Finally, the triazene 14 was selected with the best biological properties (IC50 = 3.26 ?M, NI50 = 24.22 ?M, SI = 7.44). The compound 14 showed the ability to inhibit the growth of intracellular replicating and multi-drug resistant M. tuberculosis. The results suggest the molecule to be an interesting scaffold for further study and optimization. PMID:24631899

Cappoen, Davie; Vajs, Jure; Uythethofken, Cynthia; Virag, Andrej; Mathys, Vanessa; Ko?evar, Marijan; Verschaeve, Luc; Gazvoda, Martin; Polanc, Slovenko; Huygen, Kris; Košmrlj, Janez

2014-04-22

92

Phagocyte NADPH oxidase, chronic granulomatous disease and mycobacterial infections.  

Science.gov (United States)

Infection of humans with Mycobacterium tuberculosis remains frequent and may still lead to death. After primary infection, the immune system is often able to control M. tuberculosis infection over a prolonged latency period, but a decrease in immune function (from HIV to immunosenescence) leads to active disease. Available vaccines against tuberculosis are restricted to BCG, a live vaccine with an attenuated strain of M. bovis. Immunodeficiency may not only be associated with an increased risk of tuberculosis, but also with local or disseminated BCG infection. Genetic deficiency in the reactive oxygen species (ROS)-producing phagocyte NADPH oxidase NOX2 is called chronic granulomatous disease (CGD). CGD is among the most common primary immune deficiencies. Here we review our knowledge on the importance of NOX2-derived ROS in mycobacterial infection. A literature review suggests that human CGD patient frequently have an increased susceptibility to BCG and to M. tuberculosis. In vitro studies and experiments with CGD mice are incomplete and yielded - at least in part - contradictory results. Thus, although observations in human CGD patients leave little doubt about the role of NOX2 in the control of mycobacteria, further studies will be necessary to unequivocally define and understand the role of ROS. PMID:24916152

Deffert, Christine; Cachat, Julien; Krause, Karl-Heinz

2014-08-01

93

Non-major histocompatibility complex-restricted cytotoxic activity of blood mononuclear cells stimulated with secreted mycobacterial proteins and other mycobacterial antigens  

DEFF Research Database (Denmark)

Several observations indicate that non-major histocompatibility complex (MHC)-restricted cytotoxicity, mediated for example by natural killer cells and lymphokine-activated killer cells, may serve as an important antimicrobial defense mechanism. The purpose of the present study was to investigate the influences of different mycobacterial antigens on non-MHC-restricted cytotoxicity and further to investigate the ways by which various lymphocyte subpopulations contribute to the development of this cytotoxicity. Non-MHC-restricted cytotoxicity was induced following stimulation of mononuclear cells with tuberculin purified protein derivative, Mycobacterium bovis bacillus Calmette-Guérin (BCG), short- and long-term culture filtrates of virulent Mycobacterium tuberculosis H37Rv, and 30-31-kDa secreted mycobacterial protein. These antigens also induced proliferation and production of gamma interferon. The CD4+ cells proliferated and expressed interleukin-2 receptors following stimulation with mycobacterial antigens. Depletion studies after antigen stimulation showed that the cytotoxic effector cells were CD16+ CD56+ and CD4-; the CD4+ cells alone did not mediate non-MHC-restricted cytotoxicity. To evaluate the influence of CD4+ cells on the development of non-MHC-restricted cytotoxicity, blood mononuclear cells were depleted of CD4+ cells before antigen stimulation. When mononuclear cells were incubated with purified protein derivative or short-term culture filtrate in the absence of CD4+ cells, cytotoxic activity was reduced. This reduction was abolished by interleukin-2 but not by gamma interferon. We conclude that several mycobacterial antigens are able to induce non-MHC-restricted cytotoxicity. This study indicates that non-MHC-restricted cytotoxicity following stimulation with mycobacterial antigens is induced by cytokines released by antigen-specific activated CD4+ cells.

Ravn, P; Pedersen, B K

1994-01-01

94

Atypical mycobacterial cutaneous infections in Egyptians: a clinicopathological study.  

Science.gov (United States)

Atypical mycobacteria comprise an uncommon heterogenous non-tuberculous group of acid-fast bacteria that rarely involve skin. The pattern of atypical mycobacterial cutaneous infections (AMCI) has not been previously studied in Egypt. The aim of this study was to describe the clinical characteristics, pathological features and species profile of AMCI among Egyptian patients. A retrospective study included 46 cases, diagnosed with AMCI during the period 2002 to 2012. The study included 34 males (73.9%) and 12 females (26.9%). The average age of patients was 39 years while the average duration of lesions was 15 months. The lesions were mostly located on the extremities (91.3%) and there was predominance of single (65.2%) and nodular (41.4%) lesions. History of trauma was confirmed in 91.3%. Histologically, the granulomas were mostly superficial (67.4%) with predominance of nodular suppurative pattern (84.8%). Other significant histological findings included epidermal hypertrophy (100%), presence of large-sized multinucleated giant cells (87%) and intrafollicular neutrophilic abscesses (84.8%). The diagnosis was proved by direct smear in 6.5%, skin biopsy in 10.9%, tissue culture in 47.8% and polymerase chain reaction (PCR) in 34.8%. Isolated species included Mycobacterium marinum (84.8%), Mycobacterium fortuitum (10.9%) and Mycobacterium kansasii (4.3%). Although the results of this study recommend that the diagnosis of AMCI is based mainly on culture and PCR, other clinicopathological features such as history of trauma, acral location of the lesion and suppurative granulomatous reaction with intrafollicular abscesses could be helpful clues in suspecting AMCI. PMID:24533920

El-Khalawany, Mohamed A

2014-04-01

95

Membrane TNF confers protection to acute mycobacterial infection  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Tumour necrosis factor (TNF is crucial for the control of mycobacterial infection as TNF deficient (KO die rapidly of uncontrolled infection with necrotic pneumonia. Here we investigated the role of membrane TNF for host resistance in knock-in mice with a non-cleavable and regulated allele (mem-TNF. Methods C57BL/6, TNF KO and mem-TNF mice were infected with M. tuberculosis H37Rv (Mtb at 100 CFU by intranasal administration and the survival, bacterial load, lung pathology and immunological parameters were investigated. Bone marrow and lymphocytes transfers were used to test the role of membrane TNF to confer resistance to TNF KO mice. Results While TNF-KO mice succumbed to infection within 4–5 weeks, mem-TNF mice recruited normally T cells and macrophages, developed mature granuloma in the lung and controlled acute Mtb infection. However, during the chronic phase of infection mem-TNF mice succumbed to disseminated infection with necrotic pneumonia at about 150 days. Reconstitution of irradiated TNF-KO mice with mem-TNF derived bone marrow cells, but not with lymphocytes, conferred host resistance to Mtb infection in TNF-KO mice. Conclusion Membrane expressed TNF is sufficient to allow cell-cell signalling and control of acute Mtb infection. Bone marrow cells, but not lymphocytes from mem-TNF mice confer resistance to infection in TNF-KO mice. Long-term infection control with chronic inflammation likely disrupting TNF mediated cell-cell signalling, additionally requires soluble TNF.

Yeremeev Vladimir

2005-11-01

96

Secretome differences between the taxonomically related but clinically differing mycobacterial species Mycobacterium abscessus and M. chelonae  

Directory of Open Access Journals (Sweden)

Full Text Available Rapidly growing non-tuberculous mycobacteria (NTM are significant human pathogens which show high inter-species differences in clinical characteristics (virulence, host immune response during infection even within a given NTM complex. Understanding the differences between the secreted proteomes of the member species for an NTM complex may reveal the basis of their differential virulence and host pathogenesis potential including host immune reactions. In this study, major secreted proteins of the two taxonomically close but clinically differing member species M. abscessus and M. chelonae of the M. chelonae-M. abscessus(MCA complex were compared using an approach based on 2-dimensional gel electrophoresis (2-DE and MALDI-TOF analyses. The two secretomes showed dramatic differences. Of the 73 major secreted proteins identified, majority were expressed in a species-specific manner, including 37 in M. chelonae and 32 in M. abscessus. Interestingly, 9 of these differentially expressed proteins were orphan proteins showing homology to either hypothetical proteins or those with no defined function. The other 60 distinctly expressed proteins were homologs of those associated with various bacterial cellular functions and virulence, namely cell wall synthesis or lipid metabolism, metabolic and respiratory pathways, stress response and signal transduction, gene regulation, and immune response. This information on species-specific secreted proteins would help understand the critical virulence factors and host pathogenesis mechanisms in these mycobacterial species and provide the basis for developing better therapeutic strategies. These proteins may also serve as potential targets for species-specific diagnosis as an additional outcome. To our knowledge, this is the first attempt to characterize the secretome of M. chelonae (for which the genome sequence is not yet available and the secretome differences between M. abscessus and M. chelonae.

Jagjit S. Yadav

2012-01-01

97

Multiple mycobacterial antigens are targets of the adaptive immune response in pulmonary sarcoidosis  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Introduction Sarcoidosis is a multisystem granulomatous disease for which the association with mycobacteria continues to strengthen. It is hypothesized that a single, poorly degradable antigen is responsible for sarcoidosis pathogenesis. Several reports from independent groups support mycobacterial antigens having a role in sarcoidosis pathogenesis. To identify other microbial targets of the adaptive immune response, we tested the ability of CD4+ and CD8+ T cells to recognize multiple mycobacterial antigens. Methods Fifty-four subjects were enrolled in this study: 31 sarcoidosis patients, nine non-tuberculosis mycobacterial (NTM infection controls, and 14 PPD- controls. Using flow cytometry, we assessed for Th1 immune responses to ESAT-6, katG, Ag85A, sodA, and HSP. Results Alveolar T-cells from twenty-two of the 31 sarcoidosis patients produced a CD4+ response to at least one of ESAT-6, katG, Ag85A, sodA, or HSP, compared to two of 14 PPD- controls (p = 0.0008 and five of nine NTM controls (p = 0.44, while eighteen of the 31 sarcoidosis subjects tested produced a CD8+ response to at least one of the mycobacterial antigens compared to two of 14 PPD- controls (p = 0.009 and three of nine NTM controls (0.26. Not only did the BAL-derived T cells respond to multiple virulence factors, but also to multiple, distinct epitopes within a given protein. The detection of proliferation upon stimulation with the mycobacterial virulence factors demonstrates that these responses are initiated by antigen specific recognition. Conclusions Together these results reveal that antigen-specific CD4+ and CD8+ T cells responses to multiple mycobacterial epitopes are present within sites of active sarcoidosis involvement, and that these antigen-specific responses are present at the time of diagnosis.

Jenkins Cathy

2010-11-01

98

Enhanced mycobacterial diagnostics in liquid medium by microaerobic bubble flow in Portable Microbe Enrichment Unit.  

Science.gov (United States)

Portable Microbe Enrichment Unit (PMEU) method with microaerobic bubbling speeded up the growth of otherwise slowly starting and propagating Mycobacterium sp. Mycobacterium fortuitum growth was detected after 10-11h and Mycobacterium marinum produced clear growth in 4 days. A mycobacterial environmental isolate was verified in 2 days in the PMEU Spectrion(®) equipped with infrared sensors. In parallel static (without gas bubbling) cultures hardly any growth occurred. In conclusion, PMEU technology provided thus a rapid detection of environmental and clinical mycobacterial isolates. It would also help in the field diagnosis of antibiotic resistant Mycobacterium tuberculosis. PMID:24075064

Hakalehto, Elias

2013-06-01

99

Cytodiagnosis of coexistent cryptococcal and mycobacterial lymphadenitis in a case of AIDS  

Directory of Open Access Journals (Sweden)

Full Text Available Multiple infections are a common feature of acquired immunodeficiency syndrome (AIDS, but coexistent infections at the same site are rare. In this report, we describe a 35-year-old human immunodeficiency virus infected male with coexistent cryptococcal and mycobacterial lymphadenitis. He presented with generalised lymphadenopathy. Fine needle aspiration cytology of enlarged cervical lymph node, aided by special stains, revealed coexistent cryptococcal and mycobacterial infection. Coexistent infections pose diagnostic problems in AIDS patients and are likely to be missed. Special stains are valuable for accurate diagnosis of coexistent infections.

Anvikar Arti

2011-01-01

100

Genome Sequence of Mycobacterium hassiacum DSM 44199, a Rare Source of Heat-Stable Mycobacterial Proteins  

Science.gov (United States)

Mycobacterium hassiacum is a rapidly growing mycobacterium isolated from human urine and so far the most thermophilic among mycobacterial species. Its thermotolerance and phylogenetic relationship to M. tuberculosis render its proteins attractive tools for crystallization and structure-guided drug design. We report the draft genome sequence of M. hassiacum DSM 44199. PMID:23209251

Tiago, Igor; Maranha, Ana; Mendes, Vitor; Alarico, Susana; Moynihan, Patrick J.; Clarke, Anthony J.; Macedo-Ribeiro, Sandra; Pereira, Pedro J. B.

2012-01-01

 
 
 
 
101

Genome Sequence of Mycobacterium hassiacum DSM 44199, a Rare Source of Heat-Stable Mycobacterial Proteins  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mycobacterium hassiacum is a rapidly growing mycobacterium isolated from human urine and so far the most thermophilic among mycobacterial species. Its thermotolerance and phylogenetic relationship to M. tuberculosis render its proteins attractive tools for crystallization and structure-guided drug design. We report the draft genome sequence of M. hassiacum DSM 44199.

Tiago, Igor; Maranha, Ana; Mendes, Vitor; Alarico, Susana; Moynihan, Patrick J.; Clarke, Anthony J.; Macedo-ribeiro, Sandra; Pereira, Pedro J. B.; Empadinhas, Nuno

2012-01-01

102

Biochip system for rapid and accurate identification of mycobacterial species from isolates and sputum.  

Science.gov (United States)

The accurate detection of mycobacterial species from isolates and clinical samples is important for pathogenic diagnosis and treatment and for disease control. There is an urgent need for the development of a rapid, simple, and accurate detection method. We established a biochip assay system, including a biochip, sample preparation apparatus, hybridization instrument, chip washing machine, and laser confocal scanner equipped with interpretation software for automatic diagnosis. The biochip simultaneously identified 17 common mycobacterial species by targeting the differences in the 16S rRNA. The system was assessed with 64 reference strains and 296 Mycobacterium tuberculosis and 243 nontuberculous mycobacterial isolates, as well as 138 other bacteria and 195 sputum samples, and then compared to DNA sequencing. The entire biochip assay took 6 h. The concordance rate between the biochip assay and the DNA sequencing results was 100%. In conclusion, the biochip system provides a simple, rapid, reliable, and highly accurate clinical assay for determination of mycobacterial species in a 6-h procedure, from either culture isolates or sputum samples, allowing earlier pathogen-adapted antimicrobial therapy in patients. PMID:20686082

Zhu, Lingxiang; Jiang, Guanglu; Wang, Shengfen; Wang, Can; Li, Qiang; Yu, Hao; Zhou, Yang; Zhao, Bing; Huang, Hairong; Xing, Wanli; Mitchelson, Keith; Cheng, Jing; Zhao, Yanlin; Guo, Yong

2010-10-01

103

IL-6 mediates 11?HSD type 2 to effect progression of the mycobacterial cord factor trehalose 6,6'-dimycolate-induced granulomatous response.  

Science.gov (United States)

Granulomatous structures are highly dynamic during active mycobacterial infection, with accompanying responsive inflammation contributing to modulation of pathology throughout the course of disease. The heightened inflammatory response coinciding with initiation and maintenance of newly developing granulomatous structures must be limited to avoid excessive damage to bystander tissue. Modulating the cellular bioavailability of glucocorticoids by local regulation of 11?HSD enzymes within responding tissue and parenchyma would allow controlled inflammatory response during infection. Mycobacterial glycolipid trehalose 6,6'-dimycolate was used to induce strong pulmonary granulomatous inflammation immunopathology. Pulmonary corticosterone was significantly increased at days 3 and 5 after administration. An inverse relationship of 11?HSD1 and 11?HSD2 message correlated with pathology development. Immunohistochemical analysis also demonstrated that 11?HSD2 is expressed in proximity to granulomatous lesions. A role for pro-inflammatory IL-6 cytokine in regulation of converting enzymes to control the granulomatous response was confirmed using gene-disrupted IL-6-/- mice. A model is proposed linking IL-6 to endocrine-derived factors which allows modification of active corticosterone into inert 11-dehydrocorticosterone at the site of granuloma formation to limit excessive parenchymal damage. PMID:21389736

Abbott, April N; Welsh, Kerry J; Hwang, Shen-An; P?oszaj, Paulina; Choudhury, Tina; Boyd, Sydney; Blackburn, Michael R; Hunter, Robert L; Actor, Jeffrey K

2011-01-01

104

Increased serum anti-mycobacterial antibody titers in rheumatoid arthritis patients. Is there any specific antigenic target?  

Directory of Open Access Journals (Sweden)

Presence of increased immunoreactivity against mycobacterial antigens in the sera of patients with RA was detected. When statistical analyses was considered, we cannot put forward any antigenic fraction alone as the one responsible for the increased reactivity.

Emel S. Cetin

2007-05-01

105

Apramycin resistance as a selective marker for gene transfer in mycobacteria.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We have explored the potential of using the apramycin resistance gene as a marker in mycobacterial gene transfer studies. Shuttle plasmids available for both electroporation and conjugation studies have been constructed, and we have successfully validated the use of the apramycin resistance gene as a component of cloning vectors for Mycobacterium smegmatis, M. bovis BCG, and M. tuberculosis.

Paget, E.; Davies, J.

1996-01-01

106

Biochemical and Structural Characterization of Mycobacterial Aspartyl-tRNA Synthetase AspS, a Promising TB Drug Target  

Science.gov (United States)

The human pathogen Mycobacterium tuberculosis is the causative agent of pulmonary tuberculosis (TB), a disease with high worldwide mortality rates. Current treatment programs are under significant threat from multi-drug and extensively-drug resistant strains of M. tuberculosis, and it is essential to identify new inhibitors and their targets. We generated spontaneous resistant mutants in Mycobacterium bovis BCG in the presence of 10× the minimum inhibitory concentration (MIC) of compound 1, a previously identified potent inhibitor of mycobacterial growth in culture. Whole genome sequencing of two resistant mutants revealed in one case a single nucleotide polymorphism in the gene aspS at 535GAC>535AAC (D179N), while in the second mutant a single nucleotide polymorphism was identified upstream of the aspS promoter region. We probed whole cell target engagement by overexpressing either M. bovis BCG aspS or Mycobacterium smegmatis aspS, which resulted in a ten-fold and greater than ten-fold increase, respectively, of the MIC against compound 1. To analyse the impact of inhibitor 1 on M. tuberculosis AspS (Mt-AspS) activity we over-expressed, purified and characterised the kinetics of this enzyme using a robust tRNA-independent assay adapted to a high-throughput screening format. Finally, to aid hit-to-lead optimization, the crystal structure of apo M. smegmatis AspS was determined to a resolution of 2.4 Å. PMID:25409504

Cox, Jonathan A. G.; Fütterer, Klaus; Abrahams, Katherine A.; Bhatt, Apoorva; Alderwick, Luke J.; Reynolds, Robert C.; Loman, Nicholas J.; Nataraj, VijayaShankar; Alemparte, Carlos; Barros, David; Lloyd, Adrian J.; Ballell, Lluis; Hobrath, Judith V.; Besra, Gurdyal S.

2014-01-01

107

Mycobacterial disease and impaired IFN-? immunity in humans with inherited ISG15 deficiency.  

Science.gov (United States)

ISG15 is an interferon (IFN)-?/?-inducible, ubiquitin-like intracellular protein. Its conjugation to various proteins (ISGylation) contributes to antiviral immunity in mice. Here, we describe human patients with inherited ISG15 deficiency and mycobacterial, but not viral, diseases. The lack of intracellular ISG15 production and protein ISGylation was not associated with cellular susceptibility to any viruses that we tested, consistent with the lack of viral diseases in these patients. By contrast, the lack of mycobacterium-induced ISG15 secretion by leukocytes-granulocyte, in particular-reduced the production of IFN-? by lymphocytes, including natural killer cells, probably accounting for the enhanced susceptibility to mycobacterial disease. This experiment of nature shows that human ISGylation is largely redundant for antiviral immunity, but that ISG15 plays an essential role as an IFN-?-inducing secreted molecule for optimal antimycobacterial immunity. PMID:22859821

Bogunovic, Dusan; Byun, Minji; Durfee, Larissa A; Abhyankar, Avinash; Sanal, Ozden; Mansouri, Davood; Salem, Sandra; Radovanovic, Irena; Grant, Audrey V; Adimi, Parisa; Mansouri, Nahal; Okada, Satoshi; Bryant, Vanessa L; Kong, Xiao-Fei; Kreins, Alexandra; Velez, Marcela Moncada; Boisson, Bertrand; Khalilzadeh, Soheila; Ozcelik, Ugur; Darazam, Ilad Alavi; Schoggins, John W; Rice, Charles M; Al-Muhsen, Saleh; Behr, Marcel; Vogt, Guillaume; Puel, Anne; Bustamante, Jacinta; Gros, Philippe; Huibregtse, Jon M; Abel, Laurent; Boisson-Dupuis, Stéphanie; Casanova, Jean-Laurent

2012-09-28

108

Mycobacterial disease and impaired IFN-? immunity in humans with inherited ISG15 deficiency  

Science.gov (United States)

ISG15 is an interferon (IFN)-?/?-inducible, ubiquitin-like intracellular protein. Its conjugation to various proteins (ISGylation) contributes to antiviral immunity in mice. We describe human patients with inherited ISG15 deficiency and mycobacterial, but not viral diseases. The lack of intracellular ISG15 production and protein ISGylation was not associated with cellular susceptibility to any viruses tested, consistent with the lack of viral diseases in these patients. By contrast, the lack of mycobacterium-induced ISG15 secretion by leukocytes — granulocytes in particular — reduced the production of IFN-? by lymphocytes, including natural killer cells, probably accounting for the enhanced susceptibility to mycobacterial disease. This experiment of Nature shows that human ISGylation is largely redundant for antiviral immunity, but that ISG15 plays an essential role as an IFN-?-inducing secreted molecule for optimal antimycobacterial immunity. PMID:22859821

Bogunovic, Dusan; Byun, Minji; Durfee, Larissa A.; Abhyankar, Avinash; Sanal, Ozden; Mansouri, Davood; Salem, Sandra; Radovanovic, Irena; Grant, Audrey V.; Adimi, Parisa; Mansouri, Nahal; Okada, Satoshi; Bryant, Vanessa L.; Kong, Xiao-Fei; Kreins, Alexandra; Velez, Marcela Moncada; Boisson, Bertrand; Khalilzadeh, Soheila; Ozcelik, Ugur; Darazam, Ilad Alavi; Schoggins, John W.; Rice, Charles M.; Al-Muhsen, Saleh; Behr, Marcel; Vogt, Guillaume; Puel, Anne; Bustamante, Jacinta; Gros, Philippe; Huibregtse, Jon M.; Abel, Laurent; Boisson-Dupuis, Stephanie; Casanova, Jean-Laurent

2012-01-01

109

Under-explored experimental topics related to integral mycobacterial vaccines for leprosy.  

Science.gov (United States)

Many leprosy vaccine studies have utilized live or killed whole mycobacteria, such as Bacille Calmette-Guérin, Indian Cancer Research Center (ICRC) bacilli and Mycobacterium w either alone or in combination with killed Mycobacterium leprae. For Bacille Calmette-Guérin, the vaccine dose is generally that which gives the largest delayed-type hypersensitivity response with minimal side effects. The doses of other integral mycobacterial vaccines appear to be arbitrarily chosen. Hypotheses governing immunologic responses to complex antigens predict that the doses used may be too high, resulting in protection of some individuals and increasing the susceptibility of other individuals to leprosy. The natural history of an individual's prior exposure to environmental mycobacteria will affect the outcome of protective vaccination using a given dose of mycobacterial vaccine in the individual. PMID:14711362

Gormus, Bobby J; Meyers, Wayne M

2003-12-01

110

[Nontuberculous mycobacterial keratitis: report of two cases causing infectious crystalline keratopathy].  

Science.gov (United States)

We report two cases of nontuberculous mycobacterial keratitis, occurring after corneal trauma with superficial foreign body and after perforating keratoplasty for alkali burn, respectively. Patients initially presented with indolent white corneal infiltrates, which did not respond to topical treatment. Both secondarily developed infectious crystalline keratopathy with unequal intensity. In the first case, the excised flap of lamellar keratectomy was cultured, allowing identification of Mycobacterium abscessus. Mycobacterium chelonae was isolated from a corneal biopsy in the second case. The clinical course showed poor response to antibiotic therapy consisting of ciprofloxacin and amikacin drops in conjunction with a new-generation oral macrolide. Corneal infection recurred after lamellar keratectomy in the first patient. Topical corticosteroid interruption burst corneal inflammation and induced stromal necrosis in the other patient. These intractable mycobacterial infections were finally controlled with penetrating keratoplasty. Our data suggest that a rapidly growing mycobacteria culture is required when clinical presentation consists of chronic bacterial keratitis or infectious crystalline keratopathy. PMID:12660593

Labalette, P; Maurage, C-A; Jourdel, D; Savage, C; Rouland, J-F

2003-02-01

111

Biochip System for Rapid and Accurate Identification of Mycobacterial Species from Isolates and Sputum?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The accurate detection of mycobacterial species from isolates and clinical samples is important for pathogenic diagnosis and treatment and for disease control. There is an urgent need for the development of a rapid, simple, and accurate detection method. We established a biochip assay system, including a biochip, sample preparation apparatus, hybridization instrument, chip washing machine, and laser confocal scanner equipped with interpretation software for automatic diagnosis. The biochip si...

Zhu, Lingxiang; Wang, Shengfen; Wang, Can; Li, Qiang; Yu, Hao; Zhou, Yang; Zhao, Bing; Huang, Hairong; Xing, Wanli; Mitchelson, Keith; Cheng, Jing; Zhao, Yanlin; Guo, Yong

2010-01-01

112

Calpinactam, a new anti-mycobacterial agent, produced by Mortierella alpina FKI-4905.  

Science.gov (United States)

Calpinactam, a new anti-mycobacterial agent, was isolated from the culture broth of a fungal strain Mortierella alpina FKI-4905 by solvent extraction, octadecyl silane column chromatography and preparative HPLC. Calpinactam was active only against Mycobacteria among various microorganisms, including Gram-positive and Gram-negative bacteria, fungi and yeasts. Calpinactam inhibited the growth of Mycobacterium smegmatis and Mycobacterium tuberculosis with MIC values of 0.78 and 12.5 microg ml(-1), respectively. PMID:20186169

Koyama, Nobuhiro; Kojima, Shigenobu; Nonaka, Kenichi; Masuma, Rokuro; Matsumoto, Makoto; Omura, Satoshi; Tomoda, Hiroshi

2010-04-01

113

Six recommendations for improving monitoring of diseases shared with wildlife: examples regarding mycobacterial infections in Spain  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Monitoring is needed to identify changes in disease occurrence and to measure the impact of intervention. Using mycobacterial diseases as an example, we discuss herein the pros and cons of the current Spanish Wildlife Disease Surveillance Scheme providing suggestions for monitoring relevant diseases shared with wildlife in other regions facing similar challenges. Six points should be considered. This includes: (1) making sure the disease is properly monitored in the releva...

2011-01-01

114

The molecular biology of mycobacterial trehalose in the quest for advanced tuberculosis therapies.  

Science.gov (United States)

Trehalose is a natural glucose disaccharide identified in the 19th century in fungi and insect cocoons, and later across the three domains of life. In members of the genus Mycobacterium, which includes the tuberculosis (TB) pathogen and over 160 species of nontuberculous mycobacteria (NTM), many of which are opportunistic pathogens, trehalose has been an important focus of research over the last 60 years. It is a crucial player in the assembly and architecture of the remarkable mycobacterial cell envelope as an element of unique highly antigenic glycolipids, namely trehalose dimycolate ('cord factor'). Free trehalose has been detected in the mycobacterial cytoplasm and occasionally in oligosaccharides with unknown function. TB and NTM infection statistics and death toll, the decline in immune responses in the aging population, human immunodeficiency virus/AIDS or other debilitating conditions, and the proliferation of strains with different levels of resistance to the dated drugs in use, all merge into a serious public-health threat urging more effective vaccines, efficient diagnostic tools and new drugs. This review deals with the latest findings on mycobacterial trehalose biosynthesis, catabolism, processing and recycling, as well with the ongoing quest for novel trehalose-related mechanisms to be targeted by novel TB therapeutics. In this context, the drug-discovery pipeline has recently included new lead compounds directed toward trehalose-related targets highlighting the potential of these pathways to stem the tide of rising drug resistance. PMID:24858083

Nobre, Ana; Alarico, Susana; Maranha, Ana; Mendes, Vitor; Empadinhas, Nuno

2014-08-01

115

Mycobacterial laminin-binding histone-like protein mediates collagen-dependent cytoadherence  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english When grown in the presence of exogenous collagen I, Mycobacterium bovis BCG was shown to form clumps. Scanning electron microscopy examination of these clumps revealed the presence of collagen fibres cross-linking the bacilli. Since collagen is a major constituent of the eukaryotic extracellular mat [...] rices, we assayed BCG cytoadherence in the presence of exogenous collagen I. Collagen increased the interaction of the bacilli with A549 type II pneumocytes or U937 macrophages, suggesting that BCG is able to recruit collagen to facilitate its attachment to host cells. Using an affinity chromatography approach, we have isolated a BCG collagen-binding protein corresponding to the previously described mycobacterial laminin-binding histone-like protein (LBP/Hlp), a highly conserved protein associated with the mycobacterial cell wall. Moreover, Mycobacterium leprae LBP/Hlp, a well-characterized adhesin, was also able to bind collagen I. Finally, using recombinant fragments of M. leprae LBP/Hlp, we mapped the collagen-binding activity within the C-terminal domain of the adhesin. Since this protein was already shown to be involved in the recognition of laminin and heparan sulphate-containing proteoglycans, the present observations reinforce the adhesive activities of LBP/Hlp, which can be therefore considered as a multifaceted mycobacterial adhesin, playing an important role in both leprosy and tuberculosis pathogenesis.

André Alves, Dias; Dominique, Raze; Cristiana Soares de, Lima; Maria Angela de Melo, Marques; Hervé, Drobecq; Anne-Sophie, Debrie; Michelle Lopes, Ribeiro-Guimarães; Franck, Biet; Maria Cristina Vidal, Pessolani.

2012-12-01

116

Mycobacterial laminin-binding histone-like protein mediates collagen-dependent cytoadherence  

Directory of Open Access Journals (Sweden)

Full Text Available When grown in the presence of exogenous collagen I, Mycobacterium bovis BCG was shown to form clumps. Scanning electron microscopy examination of these clumps revealed the presence of collagen fibres cross-linking the bacilli. Since collagen is a major constituent of the eukaryotic extracellular matrices, we assayed BCG cytoadherence in the presence of exogenous collagen I. Collagen increased the interaction of the bacilli with A549 type II pneumocytes or U937 macrophages, suggesting that BCG is able to recruit collagen to facilitate its attachment to host cells. Using an affinity chromatography approach, we have isolated a BCG collagen-binding protein corresponding to the previously described mycobacterial laminin-binding histone-like protein (LBP/Hlp, a highly conserved protein associated with the mycobacterial cell wall. Moreover, Mycobacterium leprae LBP/Hlp, a well-characterized adhesin, was also able to bind collagen I. Finally, using recombinant fragments of M. leprae LBP/Hlp, we mapped the collagen-binding activity within the C-terminal domain of the adhesin. Since this protein was already shown to be involved in the recognition of laminin and heparan sulphate-containing proteoglycans, the present observations reinforce the adhesive activities of LBP/Hlp, which can be therefore considered as a multifaceted mycobacterial adhesin, playing an important role in both leprosy and tuberculosis pathogenesis.

André Alves Dias

2012-12-01

117

Mycobacterial laminin-binding histone-like protein mediates collagen-dependent cytoadherence  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english When grown in the presence of exogenous collagen I, Mycobacterium bovis BCG was shown to form clumps. Scanning electron microscopy examination of these clumps revealed the presence of collagen fibres cross-linking the bacilli. Since collagen is a major constituent of the eukaryotic extracellular mat [...] rices, we assayed BCG cytoadherence in the presence of exogenous collagen I. Collagen increased the interaction of the bacilli with A549 type II pneumocytes or U937 macrophages, suggesting that BCG is able to recruit collagen to facilitate its attachment to host cells. Using an affinity chromatography approach, we have isolated a BCG collagen-binding protein corresponding to the previously described mycobacterial laminin-binding histone-like protein (LBP/Hlp), a highly conserved protein associated with the mycobacterial cell wall. Moreover, Mycobacterium leprae LBP/Hlp, a well-characterized adhesin, was also able to bind collagen I. Finally, using recombinant fragments of M. leprae LBP/Hlp, we mapped the collagen-binding activity within the C-terminal domain of the adhesin. Since this protein was already shown to be involved in the recognition of laminin and heparan sulphate-containing proteoglycans, the present observations reinforce the adhesive activities of LBP/Hlp, which can be therefore considered as a multifaceted mycobacterial adhesin, playing an important role in both leprosy and tuberculosis pathogenesis.

André Alves, Dias; Dominique, Raze; Cristiana Soares de, Lima; Maria Angela de Melo, Marques; Hervé, Drobecq; Anne-Sophie, Debrie; Michelle Lopes, Ribeiro-Guimarães; Franck, Biet; Maria Cristina Vidal, Pessolani.

118

Peptide-induced nasal tolerance for a mycobacterial heat shock protein 60 T cell epitope in rats suppresses both adjuvant arthritis and nonmicrobially induced?experimental?arthritis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Adjuvant arthritis (AA) can be induced in Lewis rats by immunization with mycobacterial antigens. Passive transfer of a T cell clone recognizing the 180–188 amino acid sequence in mycobacterial heat shock protein 60 (hsp60) was found to induce AA. In the present study, we investigated whether tolerance was obtained for this AA-associated T cell epitope after intranasal or s.c. administration of a peptide containing this epitope. Two 15-mer peptides containing the mycobacterial hsp60 sequenc...

Prakken, Berent J.; Zee, Ruurd; Anderton, Stephen M.; Kooten, Peter J. S.; Kuis, Wietse; Eden, Willem

1997-01-01

119

Rapid detection and differentiation of mycobacterial species using a multiplex PCR system  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Introduction The early diagnosis of mycobacterial infections is a critical step for initiating treatment and curing the patient. Molecular analytical methods have led to considerable improvements in the speed and accuracy of mycobacteria detection. Methods [...] The purpose of this study was to evaluate a multiplex polymerase chain reaction system using mycobacterial strains as an auxiliary tool in the differential diagnosis of tuberculosis and diseases caused by nontuberculous mycobacteria (NTM) Results Forty mycobacterial strains isolated from pulmonary and extrapulmonary origin specimens from 37 patients diagnosed with tuberculosis were processed. Using phenotypic and biochemical characteristics of the 40 mycobacteria isolated in LJ medium, 57.5% (n=23) were characterized as the Mycobacterium tuberculosis complex (MTBC) and 20% (n=8) as nontuberculous mycobacteria (NTM), with 22.5% (n=9) of the results being inconclusive. When the results of the phenotypic and biochemical tests in 30 strains of mycobacteria were compared with the results of the multiplex PCR, there was 100% concordance in the identification of the MTBC and NTM species, respectively. A total of 32.5% (n=13) of the samples in multiplex PCR exhibited a molecular pattern consistent with NTM, thus disagreeing with the final diagnosis from the attending physician. Conclusions Multiplex PCR can be used as a differential method for determining TB infections caused by NTM a valuable tool in reducing the time necessary to make clinical diagnoses and begin treatment. It is also useful for identifying species that were previously not identifiable using conventional biochemical and phenotypic techniques.

Andrea Santos, Lima; Rafael Silva, Duarte; Lilian Maria Lapa, Montenegro; Haiana Charifker, Schindler.

120

Rapid detection and differentiation of mycobacterial species using a multiplex PCR system  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Introduction The early diagnosis of mycobacterial infections is a critical step for initiating treatment and curing the patient. Molecular analytical methods have led to considerable improvements in the speed and accuracy of mycobacteria detection. Methods The purpose of this study was to evaluat [...] e a multiplex polymerase chain reaction system using mycobacterial strains as an auxiliary tool in the differential diagnosis of tuberculosis and diseases caused by nontuberculous mycobacteria (NTM) Results Forty mycobacterial strains isolated from pulmonary and extrapulmonary origin specimens from 37 patients diagnosed with tuberculosis were processed. Using phenotypic and biochemical characteristics of the 40 mycobacteria isolated in LJ medium, 57.5% (n=23) were characterized as the Mycobacterium tuberculosis complex (MTBC) and 20% (n=8) as nontuberculous mycobacteria (NTM), with 22.5% (n=9) of the results being inconclusive. When the results of the phenotypic and biochemical tests in 30 strains of mycobacteria were compared with the results of the multiplex PCR, there was 100% concordance in the identification of the MTBC and NTM species, respectively. A total of 32.5% (n=13) of the samples in multiplex PCR exhibited a molecular pattern consistent with NTM, thus disagreeing with the final diagnosis from the attending physician. Conclusions Multiplex PCR can be used as a differential method for determining TB infections caused by NTM a valuable tool in reducing the time necessary to make clinical diagnoses and begin treatment. It is also useful for identifying species that were previously not identifiable using conventional biochemical and phenotypic techniques.

Andrea Santos, Lima; Rafael Silva, Duarte; Lilian Maria Lapa, Montenegro; Haiana Charifker, Schindler.

2013-07-01

 
 
 
 
121

Tracheal granuloma because of infection with a novel mycobacterial species in an old FIV-positive cat.  

Science.gov (United States)

A 15-year-old domestic shorthair feline immunodeficiency virus-positive cat was presented with a five day history of productive cough and acute respiratory distress. Physical examination revealed inspiratory dyspnoea and diffuse gingivostomatitis. Radiographs showed an intratracheal mass located at the level of the sixth and the seventh cervical vertebrae. Bronchoscopy revealed a unique intratracheal mass occluding about 85 per cent of the tracheal lumen. The tracheal mass was removed bronchoscopically. A diagnosis of pyogranulomatous inflammation referable to a mycobacterial infection was made based on cytological and histopathological findings. 16S rRNA polymerase chain reaction testing and sequence analysis identified a novel mycobacterial species, likely a slow grower, with 95 per cent identity with Mycobacterium xenopi. To our knowledge, this is the first description of a tracheal mycobacterial granuloma in a cat, and the first time, a mycobacterium with this sequence has been identified. PMID:19261085

De Lorenzi, D; Solano-Gallego, L

2009-03-01

122

Phosphorylation of Enoyl-Acyl Carrier Protein Reductase InhA Impacts Mycobacterial Growth and Survival*  

Digital Repository Infrastructure Vision for European Research (DRIVER)

InhA, the primary target for the first line anti-tuberculosis drug isoniazid, is a key enzyme of the fatty-acid synthase II system involved in mycolic acid biosynthesis in Mycobacterium tuberculosis. In this study, we show that InhA is a substrate for mycobacterial serine/threonine protein kinases. Using a novel approach to validate phosphorylation of a substrate by multiple kinases in a surrogate host (Escherichia coli), we have demonstrated efficient phosphorylation of InhA by PknA, PknB, a...

Khan, Shazia; Nagarajan, Sathya Narayanan; Parikh, Amit; Samantaray, Sharmishtha; Singh, Albel; Kumar, Devanand; Roy, Rajendra P.; Bhatt, Apoorva; Nandicoori, Vinay Kumar

2010-01-01

123

The fish tank strikes again: Metachronous nontuberculous mycobacterial skin infection in an immunosuppressed host.  

Science.gov (United States)

An 82-year-old woman on long-term prednisolone for chronic obstructive airways disease presented with a 2-month history of nodules on her left forearm. This occurred 10 years after nodules on her right forearm caused by a culture-proven Mycobacterium marinum infection. Histopathological examination, polymerase chain reaction and culture of biopsy specimens were positive for M. chelonae. To our knowledge this is the first case of metachronous nontuberculous mycobacterial skin infection reported, and it highlights the diagnostic and therapeutic challenges of such infections. PMID:23991645

Li, Jane; Chong, Alvin H; O'Keefe, Rod; Johnson, Paul Dr

2014-11-01

124

Rapidly growing non-tuberculous mycobacterial infection in a renal transplant patient after alemtuzumab induction.  

Science.gov (United States)

Renal transplant recipients are at high risk of developing opportunistic infections particularly in the first 6 months after transplantation. Organisms causing such infections include rapidly growing non-tuberculous mycobacteria (NTM). Lymphocytes have a central role in combating mycobacterial infections. The use of lymphocyte-depleting agents, such as alemtuzumab, in the renal transplant population has increased in recent years. A case of multifocal osteomyelitis caused by one of the NTM, Mycobacterium chelonae, in a renal transplant recipient, after alemtuzumab induction, is presented. PMID:25040696

Hazara, A M; Edey, M; Roy, A; Bhandari, S

2014-10-01

125

Domain Requirements for DNA Unwinding by Mycobacterial UvrD2, an Essential DNA Helicase†  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mycobacterial UvrD2 is a DNA-dependent ATPase with 3? to 5? helicase activity. UvrD2 is an atypical helicase, insofar as its N-terminal ATPase domain resembles the superfamily I helicases UvrD/PcrA, yet it has a C-terminal HRDC domain, which is a feature of RecQ-type superfamily II helicases. The ATPase and HRDC domains are connected by a CxxC-(14)-CxxC tetracysteine module that defines a new clade of UvrD2-like bacterial helicases found only in Actinomycetales. By characterizing truncate...

Sinha, Krishna Murari; Stephanou, Nicolas C.; Unciuleac, Mihaela-carmen; Glickman, Michael S.; Shuman, Stewart

2008-01-01

126

Mycobacterial PIMs Inhibit Host Inflammatory Responses through CD14-Dependent and CD14-Independent Mechanisms  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mycobacteria develop strategies to evade the host immune system. Among them, mycobacterial LAM or PIMs inhibit the expression of pro-inflammatory cytokines by activated macrophages. Here, using synthetic PIM analogues, we analyzed the mode of action of PIM anti-inflammatory effects. Synthetic PIM1 isomer and PIM2 mimetic potently inhibit TNF and IL-12 p40 expression induced by TLR2 or TLR4 pathways, but not by TLR9, in murine macrophages. We show inhibition of LPS binding to TLR4/MD2/CD14 exp...

O Neill, Luke Anthony John; Kenny, Elaine

2011-01-01

127

Comparison of three methods of decontamination of sputum for Mycobacterial culture  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Three methods of decontamination of sputum for mycobacterial culture viz. Swah method of Nassau, Petroff’s method and NALC-NaOH method have been compared. Swab method was found to be best giving 92.3% positive cultures. Positive cultures in the other two methods were 80.7% and 78.8% respectively. The rate of contamination was equal (3.9%) in Swab and Petroff’s method, while NALC-NaOH method gave a higher contamination are (8.6%).

Damle, A. S.; Kaundinya, D. V.

1986-01-01

128

5-Nitrothiazolylthiosemicarbazones: synthesis and antimycobacterial evaluation against tubercular and non-tubercular mycobacterial species.  

Science.gov (United States)

Nineteen 5-nitrothiazolylthiosemicarbazones were synthesized from 5-nitrothiazole by three-step synthesis and evaluated for in vitro activities against seven mycobacterial species. Among them, N-(5-nitro-1, 3-thiazol-2-yl)-2-((Z)-4-[(phenylmethyl)oxy]phenylmethylidene)hydrazine-1-carbothioamide (4m) was found to be the most active compound with a minimum inhibitory concentration (MIC) of 0.23 microM against Mycobacterium tuberculosis H37 Rv, and was three times more potent than isoniazid and equally active as rifampicin. Compound 4m also inhibited six non-tubercular mycobacteria with MICs ranging from 1.88 to 30.25 microM. PMID:19929750

Sriram, Dhrmarajan; Yogeeswari, Perumal; Senthilkumar, Palaniappan; Sangaraju, Dewakar

2010-02-01

129

Alteraciones en el reclutamiento y activación de proteínas Rab durante la infección micobacteriana / Alterations in recruitment and activation of Rab proteins during mycobacterial infection  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish En el fagosoma, Mycobacterium spp. altera la activación y reclutamiento de diferentes proteínas "del gen Ras de cerebro de rata", comúnmente conocidas como Rab. En este manuscrito se revisa una serie de reportes que han demostrado que los fagosomas que contienen micobacterias tienen una expresión ma [...] yor y sostenida de Rab5, Rab11, Rab14 y Rab22a, y menor o ninguna expresión de Rab7, Rab9 y Rab6. Esto se correlaciona con aumento de la fusión de estos fagosomas con endosomas tempranos y de reciclaje, lo que les permite mantener ciertas características de compartimentos tempranos, permite que las bacterias obtengan acceso a nutrientes y previene la activación de mecanismos contra la micobacteria. La expresión de mutantes constitutivamente activos de las Rab de endosomas tempranos impide la maduración de fagosomas que contienen esferas de látex o micobacterias inactivadas por calor. Mientras que su silenciamiento, mediante ARN de interferencia o mediante dominantes negativos, induce la maduración de fagosomas micobacterianos. Los mecanismos exactos por los que las micobacterias alteran la dinámica de expresión de estas GTPasas, afectando la maduración fagolisosómica, no se han establecido. El problema podría explicarse por defectos en el reclutamiento de las proteínas que interactúan con Rab, como la cinasa-3 del fosfatidilinositol y el antígeno endosómico temprano 1. La identificación de los mecanismos empleados por Mycobacterium spp. para interrumpir el ciclo de activación de las Rab, será esencial para comprender la fisiopatología de la infección micobacteriana y útil como posibles blancos farmacológicos. Abstract in english At the phagosome level, Mycobacterium spp. alters activation and recruitment of several "Ras gene from rat brain" proteins, commonly known as Rab. Mycobacterial phagosomes have a greater and sustained expression of Rab5, Rab11, Rab14 and Rab22a, and lowered or no expression of Rab7, Rab9 and Rab6. T [...] his correlates with increased fusion of the phagosomes with early and recycling endosomes acquiring some features of early phogosomes, allowing the bacteria to gain access to nutrients and preventing the activation of anti-mycobacterial mechanisms. The expression of constitutively active mutants of Rab from the early stage endosomes prevents the maturation of phagosomes containing latex beads or heat-inactivated mycobacteria. Silencing of these mutants by interference RNA or dominant negative forms induces the maturation of mycobacterial phagosomes. The mechanisms have not been established by which mycobacteria alter the expression of these GTPases and thereby shift the phagolysosomal maturation. The problem can be explained by alterations in the recruitment of proteins that interact with Rab, such as phosphoinositide 3-kinases and early endosomal antigen 1. Identifying the mechanisms used by Mycobacterium spp. to disrupt the cycle of Rab activation will be essential to understand the pathophysiology of mycobacterial infections and usefully to potential drug targets.

Diana, Castaño; Mauricio, Rojas.

130

Alteraciones en el reclutamiento y activación de proteínas Rab durante la infección micobacteriana / Alterations in recruitment and activation of Rab proteins during mycobacterial infection  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish En el fagosoma, Mycobacterium spp. altera la activación y reclutamiento de diferentes proteínas "del gen Ras de cerebro de rata", comúnmente conocidas como Rab. En este manuscrito se revisa una serie de reportes que han demostrado que los fagosomas que contienen micobacterias tienen una expresión ma [...] yor y sostenida de Rab5, Rab11, Rab14 y Rab22a, y menor o ninguna expresión de Rab7, Rab9 y Rab6. Esto se correlaciona con aumento de la fusión de estos fagosomas con endosomas tempranos y de reciclaje, lo que les permite mantener ciertas características de compartimentos tempranos, permite que las bacterias obtengan acceso a nutrientes y previene la activación de mecanismos contra la micobacteria. La expresión de mutantes constitutivamente activos de las Rab de endosomas tempranos impide la maduración de fagosomas que contienen esferas de látex o micobacterias inactivadas por calor. Mientras que su silenciamiento, mediante ARN de interferencia o mediante dominantes negativos, induce la maduración de fagosomas micobacterianos. Los mecanismos exactos por los que las micobacterias alteran la dinámica de expresión de estas GTPasas, afectando la maduración fagolisosómica, no se han establecido. El problema podría explicarse por defectos en el reclutamiento de las proteínas que interactúan con Rab, como la cinasa-3 del fosfatidilinositol y el antígeno endosómico temprano 1. La identificación de los mecanismos empleados por Mycobacterium spp. para interrumpir el ciclo de activación de las Rab, será esencial para comprender la fisiopatología de la infección micobacteriana y útil como posibles blancos farmacológicos. Abstract in english At the phagosome level, Mycobacterium spp. alters activation and recruitment of several "Ras gene from rat brain" proteins, commonly known as Rab. Mycobacterial phagosomes have a greater and sustained expression of Rab5, Rab11, Rab14 and Rab22a, and lowered or no expression of Rab7, Rab9 and Rab6. T [...] his correlates with increased fusion of the phagosomes with early and recycling endosomes acquiring some features of early phogosomes, allowing the bacteria to gain access to nutrients and preventing the activation of anti-mycobacterial mechanisms. The expression of constitutively active mutants of Rab from the early stage endosomes prevents the maturation of phagosomes containing latex beads or heat-inactivated mycobacteria. Silencing of these mutants by interference RNA or dominant negative forms induces the maturation of mycobacterial phagosomes. The mechanisms have not been established by which mycobacteria alter the expression of these GTPases and thereby shift the phagolysosomal maturation. The problem can be explained by alterations in the recruitment of proteins that interact with Rab, such as phosphoinositide 3-kinases and early endosomal antigen 1. Identifying the mechanisms used by Mycobacterium spp. to disrupt the cycle of Rab activation will be essential to understand the pathophysiology of mycobacterial infections and usefully to potential drug targets.

Diana, Castaño; Mauricio, Rojas.

2010-06-01

131

Design, synthesis and anti-mycobacterial activity of 1,2,3,5-tetrasubstituted pyrrolyl-N-acetic acid derivatives.  

Science.gov (United States)

A novel synthesis of highly substituted pyrrole-N-acetic derivatives is described through the coupling of 1,4-diketones with amino acids following Paal-Knorr's approach. These pyrrole-N-acetic acid derivatives are found to exhibit potent anti-mycobacterial activity against Mycobacterium smegmatis and Mycobacterium tuberculosis strain H37Rv. In particular, 5n, 5q &5r are found to display excellent anti-mycobacterial activity against M. tuberculosis strain H37Rv with MIC values in the range of 2.97 ?M. Conversely, these compounds showed low cytotoxicity (selectivity index: >16.83) against HEK-293T cell line. PMID:25016370

Pagadala, Lakshmi Reddy; Mukkara, Lakshmi Devi; Singireddi, Satyanarayana; Singh, Ashita; Thummaluru, Veera Reddy; Jagarlamudi, Padma Sridevi; Guttala, Raja Sekhar; Perumal, Yogeeswari; Dharmarajan, Sriram; Upadhyayula, Suryanarayana Murty; Ummanni, Ramesh; Basireddy, Venkata Subba Reddy; Ravirala, Narender

2014-09-12

132

Genes  

Science.gov (United States)

Illustration of the placement of genes in a chromosome. A gene can be defined as a region of DNA that controls a hereditary characteristic. It usually corresponds to a sequence used in the production of a specific protein or RNA. A gene carries biological information in a form that must be copied and transmitted from each cell to all its progeny. This includes the entire functional unit: coding DNA sequences, non-coding regulatory DNA sequences, and introns. Genes can be as short as 1000 base pairs or as long as several hundred thousand base pairs. It can even be carried by more than one chromosome. The estimate for the number of genes in humans has decreased as our knowledge has increased. As of 2001, humans are thought to have between 30,000 and 40,000 genes.

Excellence, Access

2005-03-12

133

7.5-Å cryo-em structure of the mycobacterial fatty acid synthase.  

Science.gov (United States)

The mycobacterial fatty acid synthase (FAS) complex is a giant 2.0-MDa ?(6) homohexameric multifunctional enzyme that catalyzes synthesis of fatty acid precursors of mycolic acids, which are major components of the cell wall in Mycobacteria and play an important role in pathogenicity. Here, we present a three-dimensional reconstruction of the Mycobacterium smegmatis FAS complex at 7.5Å, highly homologous to the Mycobacterium tuberculosis multienzyme, by cryo-electron microscopy. Based on the obtained structural data, which allowed us to identify secondary-structure elements, and sequence homology with the fungal FAS, we generated an accurate architectural model of the complex. The FAS system from Mycobacteria resembles a minimized version of the fungal FAS with much larger openings in the reaction chambers. These architectural features of the mycobacterial FAS may be important for the interaction with mycolic acid processing and condensing enzymes that further modify the precursors produced by FAS and for autoactivation of the FAS complex. PMID:23291528

Boehringer, Daniel; Ban, Nenad; Leibundgut, Marc

2013-03-11

134

Assay development for identifying inhibitors of the mycobacterial FadD32 activity.  

Science.gov (United States)

FadD32, a fatty acyl-AMP ligase (FAAL32) involved in the biosynthesis of mycolic acids, major and specific lipid components of the mycobacterial cell envelope, is essential for the survival of Mycobacterium tuberculosis, the causative agent of tuberculosis. The protein catalyzes the conversion of fatty acid to acyl-adenylate (acyl-AMP) in the presence of adenosine triphosphate and is conserved in all the mycobacterial species sequenced so far, thus representing a promising target for the development of novel antituberculous drugs. Here, we describe the optimization of the protein purification procedure and the development of a high-throughput screening assay for FadD32 activity. This spectrophotometric assay measuring the release of inorganic phosphate was optimized using the Mycobacterium smegmatis FadD32 as a surrogate enzyme. We describe the use of T m (melting temperature) shift assay, which measures the modulation of FadD32 thermal stability, as a tool for the identification of potential ligands and for validation of compounds as inhibitors. Screening of a selected library of compounds led to the identification of five novel classes of inhibitors. PMID:23364516

Galandrin, Ségolène; Guillet, Valérie; Rane, Rajendra S; Léger, Mathieu; N, Radha; Eynard, Nathalie; Das, Kaveri; Balganesh, Tanjore S; Mourey, Lionel; Daffé, Mamadou; Marrakchi, Hedia

2013-06-01

135

Rapid susceptibility testing of Mycobacterium tuberculosis by bioluminescence assay of mycobacterial ATP  

International Nuclear Information System (INIS)

Mycobacterial growth was monitored by bioluminescence assay of mycobacterial ATP. Cultures of Mycobacterium tuberculosis H37Rv and of 25 clinical isolates of the same species were exposed to serial dilutions of ethambutol, isoniazid, rifampin, and streptomycin. A suppression of ATP, indicating growth inhibition, occurred for susceptible but not resistant strains within 5 to 7 days of incubation. Breakpoint concentrations between susceptibility and resistance were determined by comparing these results with those obtained by reference techniques. Full agreement was found in 99% of the assays with the resistance ratio method on Lowenstein-Jensen medium, and 98% of the assays were in full agreement with the radiometric system (BACTEC). A main advantage of the bioluminescence method is its rapidity, with results available as fast as with the radiometric system but at a lower cost and without the need for radioactive culture medium. The method provides kinetic data concerning drug effects within available in vivo drug concentrations and has great potential for both rapid routine susceptibility testing and research applications in studies of drug effects on mycobacteria

136

Rapid susceptibility testing of Mycobacterium tuberculosis by bioluminescence assay of mycobacterial ATP  

Energy Technology Data Exchange (ETDEWEB)

Mycobacterial growth was monitored by bioluminescence assay of mycobacterial ATP. Cultures of Mycobacterium tuberculosis H37Rv and of 25 clinical isolates of the same species were exposed to serial dilutions of ethambutol, isoniazid, rifampin, and streptomycin. A suppression of ATP, indicating growth inhibition, occurred for susceptible but not resistant strains within 5 to 7 days of incubation. Breakpoint concentrations between susceptibility and resistance were determined by comparing these results with those obtained by reference techniques. Full agreement was found in 99% of the assays with the resistance ratio method on Lowenstein-Jensen medium, and 98% of the assays were in full agreement with the radiometric system (BACTEC). A main advantage of the bioluminescence method is its rapidity, with results available as fast as with the radiometric system but at a lower cost and without the need for radioactive culture medium. The method provides kinetic data concerning drug effects within available in vivo drug concentrations and has great potential for both rapid routine susceptibility testing and research applications in studies of drug effects on mycobacteria.

Nilsson, L.E.; Hoffner, S.E.; Ansehn, S.

1988-08-01

137

[Evaluation of mycobacterial infections using 18F-fluorodeoxyglucose-positron emission tomography: results of nine cases].  

Science.gov (United States)

18F-fluorodeoxyglucose-positron emission tomography (FDG-PET/CT) is a useful technique for distinguishing malignant and benign lesions, although the occurrence of false-positive results in cases involving benign lesions is possible. We evaluated nine patients with mycobacterial infections who underwent FDG-PET/CT from April 2008 to July 2010. FDG-PET/CT was performed 1-2h (during the early and late phases) after administration of FDG at a dose of 185 MBq/individual after fasting for at least 5h. Out of the nine patients, four were diagnosed with pulmonary nonmycobacterium tuberculosis, two with pulmonary tuberculosis, two with tuberculous lymphadenopathy, and one with pleural tuberculoma. All patients had a maximum standardized uptake value (SUV(max)) of > 2.5, and the SUV(max) increased from the early to the late phase. One lesion that occurred due to tuberculous pleurisy after treatment demonstrated high FDG uptake, similar to the other cases. It is difficult to distinguish mycobacterial infections from malignant diseases using FGD-PET alone; hence, the use of high-resolution CT and bacteriological tests is required for diagnosis and distinction. PMID:24716357

Uruga, Hironori; Ishihara, Makiko; Hanada, Shigeo; Takaya, Hisashi; Miyamoto, Atsushi; Morokawa, Nasa; Fujii, Takeshi; Kurosaki, Atsuko; Kishi, Kazuma

2014-02-01

138

Characterization of two heparan sulphate-binding sites in the mycobacterial adhesin Hlp  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The histone-like Hlp protein is emerging as a key component in mycobacterial pathogenesis, being involved in the initial events of host colonization by interacting with laminin and glycosaminoglycans (GAGs. In the present study, nuclear magnetic resonance (NMR was used to map the binding site(s of Hlp to heparan sulfate and identify the nature of the amino acid residues directly involved in this interaction. Results The capacity of a panel of 30 mer synthetic peptides covering the full length of Hlp to bind to heparin/heparan sulfate was analyzed by solid phase assays, NMR, and affinity chromatography. An additional active region between the residues Gly46 and Ala60 was defined at the N-terminal domain of Hlp, expanding the previously defined heparin-binding site between Thr31 and Phe50. Additionally, the C-terminus, rich in Lys residues, was confirmed as another heparan sulfate binding region. The amino acids in Hlp identified as mediators in the interaction with heparan sulfate were Arg, Val, Ile, Lys, Phe, and Thr. Conclusion Our data indicate that Hlp interacts with heparan sulfate through two distinct regions of the protein. Both heparan sulfate-binding regions here defined are preserved in all mycobacterial Hlp homologues that have been sequenced, suggesting important but possibly divergent roles for this surface-exposed protein in both pathogenic and saprophic species.

Previato Jose O

2008-05-01

139

Active site of mycobacterial dUTPase: Structural characteristics and a built-in sensor  

International Nuclear Information System (INIS)

dUTPases are essential to eliminate dUTP for DNA integrity and provide dUMP for thymidylate biosynthesis. Mycobacterium tuberculosis apparently lacks any other thymidylate biosynthesis pathway, therefore dUTPase is a promising antituberculotic drug target. Crystal structure of the mycobacterial enzyme in complex with the isosteric substrate analog, ?,?-imido-dUTP and Mg2+ at 1.5 A resolution was determined that visualizes the full-length C-terminus, previously not localized. Interactions of a conserved motif important in catalysis, the Mycobacterium-specific five-residue-loop insert and C-terminal tetrapeptide could now be described in detail. Stacking of C-terminal histidine upon the uracil moiety prompted replacement with tryptophan. The resulting sensitive fluorescent sensor enables fast screening for binding of potential inhibitors to the active site. Kd for ?,?-imido-dUTP binding to mycobacterial dUTPase is determined to be 10-fold less than for human dUTPase, which is to be considered in drug optimization. A robust continuous activity assay for kinetic screening is proposed

140

Improved mycobacterial protein production using a Mycobacterium smegmatis groEL1?C expression strain  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The non-pathogenic bacterium Mycobacterium smegmatis is widely used as a near-native expression host for the purification of Mycobacterium tuberculosis proteins. Unfortunately, the Hsp60 chaperone GroEL1, which is relatively highly expressed, is often co-purified with polyhistidine-tagged recombinant proteins as a major contaminant when using this expression system. This is likely due to a histidine-rich C-terminus in GroEL1. Results In order to improve purification efficiency and yield of polyhistidine-tagged mycobacterial target proteins, we created a mutant version of GroEL1 by removing the coding sequence for the histidine-rich C-terminus, termed GroEL1?C. GroEL1?C, which is a functional protein, is no longer able to bind nickel affinity beads. Using a selection of challenging test proteins, we show that GroEL1?C is no longer present in protein samples purified from the groEL1?C expression strain and demonstrate the feasibility and advantages of purifying and characterising proteins produced using this strain. Conclusions This novel Mycobacterium smegmatis expression strain allows efficient expression and purification of mycobacterial proteins while concomitantly removing the troublesome contaminant GroEL1 and consequently increasing the speed and efficiency of protein purification.

Poulsen Christian

2011-03-01

 
 
 
 
141

Anti-mycobacterial activities of synthetic cationic ?-helical peptides and their synergism with rifampicin.  

Science.gov (United States)

The rapid emergence of multi-drug resistant tuberculosis (TB) and the lack of effective therapies have prompted the development of compounds with novel mechanisms of action to tackle this growing public health concern. In this study, a series of synthetic cationic ?-helical antimicrobial peptides (AMPs) modified with different hydrophobic amino acids was investigated for their anti-mycobacterial activity, both alone and in synergistic combinations with the frontline anti-tuberculosis drug rifampicin. The addition of thiol groups by incorporating cysteine residues in the AMPs did not improve anti-mycobacterial activity against drug-susceptible and drug-resistant Mycobacterium tuberculosis, while the enhancement of peptide hydrophobicity by adding methionine residues increased the efficacy of the primary peptide against all strains tested, including clinically isolated multidrug-resistant mycobacteria. The peptide with the optimal composition M(LLKK)2M was bactericidal, and eradicated mycobacteria via a membrane-lytic mechanism as demonstrated by confocal microscopic studies. Mycobacteria did not develop resistance after multiple exposures to sub-lethal doses of the peptide. In addition, the peptide displayed synergism with rifampicin against both Mycobacterium smegmatis and Mycobacterium bovis BCG and additivity against M. tuberculosis. Moreover, such combination therapy is effective in delaying the emergence of rifampicin resistance. The ability to potentiate anti-TB drug activity, kill drug-resistant bacteria and prevent drug resistance highlights the potential utility of the peptide in combating multidrug-resistant TB. PMID:24314557

Khara, Jasmeet S; Wang, Ying; Ke, Xi-Yu; Liu, Shaoqiong; Newton, Sandra M; Langford, Paul R; Yang, Yi Yan; Ee, Pui Lai Rachel

2014-02-01

142

Restoration of innate immune activation accelerates Th1-cell priming and protection following pulmonary mycobacterial infection.  

Science.gov (United States)

The immune mechanisms underlying delayed induction of Th1-type immunity in the lungs following pulmonary mycobacterial infection remain poorly understood. We have herein investigated the underlying immune mechanisms for such delayed responses and whether a selected innate immune-modulating strategy can accelerate Th1-type responses. We have found that, in the early stage of pulmonary infection with attenuated Mycobacterium tuberculosis (M.tb H37Ra), the levels of infection in the lung continue to increase logarithmically until days 14 and 21 postinfection in C57BL/6 mice. The activation of innate immune responses, particularly DCs, in the lung is delayed. This results in a delay in the subsequent downstream immune responses including the migration of antigen-bearing DCs to the draining lymph node (dLN), the Th1-cell priming in dLN, and the recruitment of Th1 cells to the lung. However, single lung mucosal exposure to the TLR agonist FimH postinfection is able to accelerate protective Th1-type immunity via facilitating DC migration to the lung and draining lymph nodes, enhancing DC antigen presentation and Th1-cell priming. These findings hold implications for the development of immunotherapeutic and vaccination strategies and suggest that enhancement of early innate immune activation is a viable option for improving Th1-type immunity against pulmonary mycobacterial diseases. PMID:24519467

Lai, Rocky; Jeyanathan, Mangalakumari; Shaler, Christopher R; Damjanovic, Daniela; Khera, Amandeep; Horvath, Carly; Ashkar, Ali A; Xing, Zhou

2014-05-01

143

Relief from Zmp1-mediated arrest of phagosome maturation is associated with facilitated presentation and enhanced immunogenicity of mycobacterial antigens.  

Science.gov (United States)

Pathogenic mycobacteria escape host innate immune responses by blocking phagosome-lysosome fusion. Avoiding lysosomal delivery may also be involved in the capacity of mycobacteria to evade major histocompatibility complex (MHC) class I- or II-dependent T-cell responses. In this study, we used a genetic mutant of Mycobacterium bovis BCG that is unable to escape lysosomal transfer and show that presentation of mycobacterial antigens is affected by the site of intracellular residence. Compared to infection with wild-type BCG, infection of murine bone marrow-derived dendritic cells with a mycobacterial mutant deficient in zinc metalloprotease 1 (Zmp1) resulted in increased presentation of MHC class II-restricted antigens, as assessed by activation of mycobacterial Ag85A-specific T-cell hybridomas. The zmp1 deletion mutant was more immunogenic in vivo, as measured by delayed-type hypersensitivity (DTH), antigen-specific lymphocyte proliferation, and the frequency of antigen-specific gamma interferon (IFN-?)-producing lymphocytes of both CD4 and CD8 subsets. In conclusion, our results suggest that phagosome maturation and lysosomal delivery of BCG facilitate mycobacterial antigen presentation and enhance immunogenicity. PMID:21471301

Johansen, Pål; Fettelschoss, Antonia; Amstutz, Beat; Selchow, Petra; Waeckerle-Men, Ying; Keller, Peter; Deretic, Vojo; Held, Leonhard; Kündig, Thomas M; Böttger, Erik C; Sander, Peter

2011-06-01

144

The DNA damage-regulated autophagy modulator DRAM1 links mycobacterial recognition via TLP-MYD88 to authophagic defense.  

Science.gov (United States)

Autophagy is an important defense mechanism against mycobacteria, the causative agents of tuberculosis. The molecular mechanisms that link mycobacterial recognition to autophagy remain unclear. Our analysis in zebrafish and human macrophage models of mycobacterial infection reveals that the DNA damage-regulated autophagy modulator DRAM1 functions downstream of pathogen recognition by the Toll-like receptor (TLR)/interleukin-1 receptor (IL1R)-MYD88-NF-?B innate immune sensing pathway to activate selective autophagy. Mycobacterial infection of human macrophages and zebrafish embryos induced DRAM1 expression in a MYD88 and NF-?B-dependent manner. DRAM1 knockdown increased mycobacterial infection, whereas overexpression lowered infection by hyperactivating autophagy. DRAM1-mediated selective autophagic defenses require the cytosolic DNA sensor STING and the selective autophagy receptor p62/SQSTM1. Contrary to its known role in autophagy-mediated cell death and cancer, this DRAM1 function is p53 independent. We propose that DRAM1 mediates autophagic defense against a broader range of intracellular pathogens, since DRAM1 expression was also induced by the common bacterial endotoxin lipopolysaccharide. PMID:24922577

van der Vaart, Michiel; Korbee, Cornelis J; Lamers, Gerda E M; Tengeler, Anouk C; Hosseini, Rohola; Haks, Mariëlle C; Ottenhoff, Tom H M; Spaink, Herman P; Meijer, Annemarie H

2014-06-11

145

Immune reconstitution inflammatory syndrome in HIV-infected patients with mycobacterial infections starting highly active anti-retroviral therapy  

Energy Technology Data Exchange (ETDEWEB)

AIM: To describe the radiological appearances of immune reconstitution inflammatory syndrome (IRIS) in human immunodeficiency virus (HIV)-infected patients with mycobacterial infections starting highly active anti-retroviral therapy (HAART). MATERIALS AND METHODS: Five consecutive HIV infected patients with IRIS due to mycobacterial infection were studied. Intercurrent infection and poor drug compliance were excluded as causes of presentation. The chest radiological appearances at the time of starting HAART and at the time of diagnosis of IRIS were compared. RESULTS: In these five patients there was clinical and radiological deterioration, occurring between 10 days and 7 months after starting HAART, leading to unmasking of previously undiagnosed mycobacterial infection or to worsening of mycobacterial disease. All five patients had HAART-induced increases in CD4+ T lymphocyte counts and reductions in peripheral blood HIV 'viral load'. Chest radiographic abnormalities due to IRIS included marked mediastinal lymphadenopathy in three patients--severe enough to produce tracheal compression in two patients (one of whom had stridor)--and was associated with new pulmonary infiltrates in two patients. The other two patients had new infiltrates, which in one patient was associated with a pleural effusion. CONCLUSION: These cases illustrate the diverse chest radiographic appearances of IRIS occurring after HAART in patients with mycobacterial and HIV co-infection. Marked mediastinal lymphadenopathy occurred in three of these five patients (with associated tracheal narrowing in two patients); four patients developed pulmonary infiltrates and one had an effusion. The cases further highlight that the onset of IRIS may be delayed for several months after HAART is started.

Buckingham, S.J.; Haddow, L.J.; Shaw, P.J.; Miller, R.F. E-mail: rmiller@gum.ucl.ac.uk

2004-06-01

146

Immune reconstitution inflammatory syndrome in HIV-infected patients with mycobacterial infections starting highly active anti-retroviral therapy  

International Nuclear Information System (INIS)

AIM: To describe the radiological appearances of immune reconstitution inflammatory syndrome (IRIS) in human immunodeficiency virus (HIV)-infected patients with mycobacterial infections starting highly active anti-retroviral therapy (HAART). MATERIALS AND METHODS: Five consecutive HIV infected patients with IRIS due to mycobacterial infection were studied. Intercurrent infection and poor drug compliance were excluded as causes of presentation. The chest radiological appearances at the time of starting HAART and at the time of diagnosis of IRIS were compared. RESULTS: In these five patients there was clinical and radiological deterioration, occurring between 10 days and 7 months after starting HAART, leading to unmasking of previously undiagnosed mycobacterial infection or to worsening of mycobacterial disease. All five patients had HAART-induced increases in CD4+ T lymphocyte counts and reductions in peripheral blood HIV 'viral load'. Chest radiographic abnormalities due to IRIS included marked mediastinal lymphadenopathy in three patients--severe enough to produce tracheal compression in two patients (one of whom had stridor)--and was associated with new pulmonary infiltrates in two patients. The other two patients had new infiltrates, which in one patient was associated with a pleural effusion. CONCLUSION: These cases illustrate the diverse chest radiographic appearances of IRIS occurring after HAART in patients with mycobacterial and HIV co-infection. Marked mediasterial and HIV co-infection. Marked mediastinal lymphadenopathy occurred in three of these five patients (with associated tracheal narrowing in two patients); four patients developed pulmonary infiltrates and one had an effusion. The cases further highlight that the onset of IRIS may be delayed for several months after HAART is started

147

Heat shock protein 65 induces CD62e, CD106, and CD54 on cultured human endothelial cells and increases their adhesiveness for monocytes and granulocytes.  

Science.gov (United States)

Expression of members of the heat shock protein 60 (hsp60) family in tissues has been reported to coincide with leukocyte infiltration, but it is not known whether these proteins are directly involved in the extravasation of leukocytes. Extravasation of leukocytes requires their adhesion to endothelial cells (EC) via an interaction between adhesion molecules expressed on both cell types. The aim of the present study was to investigate the effect of recombinant mycobacterial hsp65 on the adhesive characteristics of EC for monocytes and granulocytes. Incubation of EC with hsp65 induces a concentration- and time-dependent increase in adhesiveness of these EC for monocytes and granulocytes. The effect was maximal after incubation of EC with hsp65 for 4 to 6 h. In addition, incubation of EC with hsp65 induced the expression of endothelial CD62E (E-selectin), CD106 (vascular cell adhesion molecule-1) and CD54 (intercellular adhesion molecule-1). The increased adhesion of granulocytes to hsp65-stimulated EC was inhibited completely by blocking Ab against CD62E. mAb against endothelial CD62E, CD106, or CD54 or against the monocyte adhesion molecules CD14 or CD49d (very late Ag-4) did not inhibit the increased adhesion of monocytes to hsp65-stimulated EC; however, mAb against the monocyte adhesion molecule CD18 (beta2-integrin) inhibited monocyte adhesion to hsp65-stimulated EC to the same extent as monocyte adhesion to nonstimulated EC. Hsp65 did not exert its effect in an autocrine or paracrine fashion via the endogenous production of IL-1, TNF-alpha, or other factors or via contaminating LPS. Together these results indicate that hsp65 can play an important role in the adhesion of monocytes and granulocytes to EC at sites of inflammation via modulation of the adhesive characteristics of EC and thus may facilitate extravasation of these phagocytes. PMID:8683139

Verdegaal, M E; Zegveld, S T; van Furth, R

1996-07-01

148

Mycobacterial Diseases  

Science.gov (United States)

... JavaScript on. Read more information on enabling JavaScript. Mycobacteria Top Banner Content Area Main Content Area There are more than 70 species of mycobacteria—rod-shaped bacteria with waxy outer coats that ...

149

Highly Deviated Asymmetric Division in Very Low Proportion of Mycobacterial Mid-log Phase Cells.  

Science.gov (United States)

In this study, we show that about 20% of the septating Mycobacterium smegmatis and Mycobacterium xenopi cells in the exponential phase populationdivideasymmetrically, with an unusually high deviation (17 ± 4%) in the division site from the median, to generate short cells and long cells, thereby generating population heterogeneity. This mode of division is very different from the symmetric division of themajority (about 80%) of the septating cells in the Mycobacterium smegmatis, Mycobacterium marinum, and Mycobacterium bovis BCG exponential phase population, with 5-10% deviation in the division site from the mid-cell site, as reported by recent studies. The short cells and the long cells further grew and divided to generate a population. We speculate that the generation of the short cells and the long cells through the highly deviated asymmetric divisionin the low proportions of mycobacterial population may have a role in stress tolerance. PMID:24949109

Vijay, Srinivasan; Mukkayyan, Nagaraja; Ajitkumar, Parthasarathi

2014-01-01

150

Exposure to a cutinase-like serine esterase triggers rapid lysis of multiple mycobacterial species.  

Science.gov (United States)

Mycobacteria are shaped by a thick envelope made of an array of uniquely structured lipids and polysaccharides. However, the spatial organization of these molecules remains unclear. Here, we show that exposure to an esterase from Mycobacterium smegmatis (Msmeg_1529), hydrolyzing the ester linkage of trehalose dimycolate in vitro, triggers rapid and efficient lysis of Mycobacterium tuberculosis, Mycobacterium bovis BCG, and Mycobacterium marinum. Exposure to the esterase immediately releases free mycolic acids, while concomitantly depleting trehalose mycolates. Moreover, lysis could be competitively inhibited by an excess of purified trehalose dimycolate and was abolished by a S124A mutation affecting the catalytic activity of the esterase. These findings are consistent with an indispensable structural role of trehalose mycolates in the architectural design of the exposed surface of the mycobacterial envelope. Importantly, we also demonstrate that the esterase-mediated rapid lysis of M. tuberculosis significantly improves its detection in paucibacillary samples. PMID:23155047

Yang, Yong; Bhatti, Alexandra; Ke, Danxia; Gonzalez-Juarrero, Mercedes; Lenaerts, Anne; Kremer, Laurent; Guerardel, Yann; Zhang, Peijun; Ojha, Anil K

2013-01-01

151

New antituberculotics originated from salicylanilides with promising in vitro activity against atypical mycobacterial strains.  

Science.gov (United States)

A new series of 30 N-protected amino acid esters were prepared as a part of ongoing search for new anti-tuberculosis active salicylanilides. The esters possess high in vitro activity against Mycobacterium tuberculosis, Mycobacterium avium, and two strains of Mycobacterium kansasii, where one is an isolate from the patient, with MIC in the range 1-32 micromol/L for all tested strains. The prepared esters can be considered as prodrugs with better bio-availability and as more efficient transport forms through the mycobacterial cell membranes due to the higher lipophilicity. The experimental and calculated lipophilicity, stability, antituberculotic activity, cytotoxicity as well as the quantitative structure-activity relationships (QSARs) explored by the Intelligent Problem Solver (IPS) in Trajan Neural Network Simulator 6.0 are presented. PMID:19403314

Imramovský, Ales; Vinsová, Jarmila; Férriz, Juana Monreal; Dolezal, Rafael; Jampílek, Josef; Kaustová, Jarmila; Kunc, Filip

2009-05-15

152

Rapid radiometric methods to detect and differentiate Mycobacterium tuberculosis/M. bovis from other mycobacterial species  

International Nuclear Information System (INIS)

Rapid methods for the differentiation of Mycobacterium tuberculosis/M. bovis (TB complex) from other mycobacteria (MOTT bacilli) were developed and evaluated in a three-phase study. In the first phase, techniques for identification of Mycobacterium species were developed by using radiometric technology and BACTEC Middlebrook 7H12 liquid medium. Based on 14CO2 evolution, characteristic growth patterns were established for 13 commonly encountered mycobacterial species. Mycobacteria belonging to the TB complex were differentiated from other mycobacteria by cellular morphology and rate of 14CO2 evolution. For further differentiation, radiometric tests for niacin production and inhibition by Q-nitro-alpha-acetyl amino-beta-hydroxy-propiophenone (NAP) were developed. In the second phase, 100 coded specimens on Lowenstein-Jensen medium were identified as members of the TB complex, MOTT bacilli, bacteria other than mycobacteria, or ''no viable organisms'' within 3 to 12 (average 6.4) days of receipt from the Centers for Disease Control. Isolation and identification of mycobacteria from 20 simulated sputum specimens were carried out in phase III. Out of 20 sputum specimens, 16 contained culturable mycobacteria, and all of the positives were detected by the BACTEC method in an average of 7.3 days. The positive mycobacterial cultures were isolated and identified as TB complex or MOTT bacilli in an average of 12.8 days. The radiometric NAP test was found to be highly sensitive and specific for a rapid identification of TB complex, whereas the radiometric niacin test was found to have some inherent problems. Radiometric BACTEC and conventional methodologies were in complete agreement in Phase II as well as in Phase III

153

Rapid radiometric methods to detect and differentiate Mycobacterium tuberculosis/M. bovis from other mycobacterial species  

Energy Technology Data Exchange (ETDEWEB)

Rapid methods for the differentiation of Mycobacterium tuberculosis/M. bovis (TB complex) from other mycobacteria (MOTT bacilli) were developed and evaluated in a three-phase study. In the first phase, techniques for identification of Mycobacterium species were developed by using radiometric technology and BACTEC Middlebrook 7H12 liquid medium. Based on /sup 14/CO/sub 2/ evolution, characteristic growth patterns were established for 13 commonly encountered mycobacterial species. Mycobacteria belonging to the TB complex were differentiated from other mycobacteria by cellular morphology and rate of /sup 14/CO/sub 2/ evolution. For further differentiation, radiometric tests for niacin production and inhibition by Q-nitro-alpha-acetyl amino-beta-hydroxy-propiophenone (NAP) were developed. In the second phase, 100 coded specimens on Lowenstein-Jensen medium were identified as members of the TB complex, MOTT bacilli, bacteria other than mycobacteria, or ''no viable organisms'' within 3 to 12 (average 6.4) days of receipt from the Centers for Disease Control. Isolation and identification of mycobacteria from 20 simulated sputum specimens were carried out in phase III. Out of 20 sputum specimens, 16 contained culturable mycobacteria, and all of the positives were detected by the BACTEC method in an average of 7.3 days. The positive mycobacterial cultures were isolated and identified as TB complex or MOTT bacilli in an average of 12.8 days. The radiometric NAP test was found to be highly sensitive and specific for a rapid identification of TB complex, whereas the radiometric niacin test was found to have some inherent problems. Radiometric BACTEC and conventional methodologies were in complete agreement in Phase II as well as in Phase III.

Siddiqi, S.H.; Hwangbo, C.C.; Silcox, V.; Good, R.C.; Snider, D.E. Jr.; Middlebrook, G.

1984-10-01

154

Nontuberculous mycobacterial infection attributable to Mycobacterium intracellulare serotype 10 in two rhesus monkeys.  

Science.gov (United States)

Infection with Mycobacterium intracellulare serotype 10 was diagnosed in 2 rhesus monkeys (Macaca mulatta) in a closed colony of 90 animals. The clinicopathologic presentation in 1 animal with advanced disease was characterized by a precipitous weight loss, therapeutically unresponsive diarrhea, anemia, weakness, prostration, refractory tuberculin tests (using mammalian old tuberculin and M bovis purified protein derivative tuberculin), and disseminated granulomas in the lungs, spleen, liver, kidneys, lymph nodes, salivary glands, and intestines. The lamina propria throughout the large and small intestines was infiltrated with mycobacteria-laden macrophages. Severe hypoproteinemia, hypoalbuminemia, hypoglobulinemia, mild hypocalcemia, and edema were compatible with a malabsorption-like syndrome. The 2nd animal was clinically normal, but a weak positive tuberculin reaction to M bovis purified protein derivative at 72 hours necessitated euthanasia. This animal's disease was characterized by microgranulomas in the lungs, bronchial lymph nodes, liver, and pancreas, without involvement of the gastrointestinal tract. There was no evidence of M intracellulare infection in the remaining 88 animals in the colony, as determined by mycobacterial cultures of tracheobronchial washings, additional tuberculin testing, thoracic radiography, and mycobacterial culture of the drinking water. Tuberculin testing and thoracic radiographs of personnel working with the nonhuman primates were also negative. These cases were considered to be important because both animals were infected with the same serotype and because there has been an increasing number of isolations of this organism in human infections throughout Massachusetts. Drug-sensitivity testing revealed the organism to be sensitive to cycloserine and resistant to isoniazid, rifampin, ethambutol, streptomycin, kanamycin, and pyrazinamide. PMID:7174460

Fleischman, R W; du Moulin, G C; Esber, H J; Ilievski, V; Bogden, A E

1982-12-01

155

microRNA-124 negatively regulates TLR signaling in alveolar macrophages in response to mycobacterial infection.  

Science.gov (United States)

The emerging roles of microRNAs (miRNAs) in regulating immune responses have attracted increasing attention in recent years; and the alveolar macrophages (AMs) are the main targets of mycobacterial infection, which play a pivotal role in the pathogenesis of Mycobacterium tuberculosis infection. However, the immunoregulatory role of miRNAs in AMs has not been fully demonstrated. In this study, we find that miR-124 is up-regulated in the peripheral leukocytes of patients with pulmonary tuberculosis; furthermore, the expression miR-124 can be induced upon Mycobacterium bovis Bacillus Calmette-Guerin (BCG) infection in both RAW264.7 AM cells in vitro and murine AMs in vivo. Mechanistically, miR-124 is able to modulate toll-like receptor (TLR) signaling activity in RAW264.7 cells in response to BCG infection. In this regard, multiple components of TLR signaling cascade, including the TLR6, myeloid differentiation factor 88 (MyD88), TNFR-associated factor 6 and tumor necrosis factor-? are directly targeted by miR-124. In addition, both overexpression of TLR signaling adaptor MyD88 and BCG infection are able to augment miR-124 transcription, while MyD88 expression silenced by small interfering RNA dramatically suppresses miR-124 expression in AMs in vitro. Moreover, the abundance of miR-124 transcript in murine AMs of MyD88 deficient mice is significantly less than that of their wild-type or heterozygous littermates; and the BCG infection fails to induce miR-124 expression in the lung of MyD88 deficient mouse. These results indicate a negative regulatory role of miR-124 in fine-tuning inflammatory response in AMs upon mycobacterial infection, in part through a mechanism by directly targeting TLR signaling. PMID:24995397

Ma, Chunyan; Li, Yong; Li, Min; Deng, Guangcun; Wu, Xiaoling; Zeng, Jin; Hao, Xiujing; Wang, Xiaoping; Liu, Jing; Cho, William C S; Liu, Xiaoming; Wang, Yujiong

2014-11-01

156

Mycobacterial MazG is a novel NTP pyrophosphohydrolase involved in oxidative stress response.  

Science.gov (United States)

MazG nucleoside triphosphate pyrophosphohydrolase (NTP-PPase, EC 3.6.1.8) from the avirulent Mycobacterium tuberculosis H37Ra contains a spontaneous mutation on a highly conserved residue, resulting in an A219E substitution (MtMazG[A219E]). In this work, we show that mycobacterial MazG from either the virulent M. tuberculosis H37Rv (MtMazG) or the fast-growing Mycobacterium smegmatis (MsMazG) is a potent NTP-PPase capable of hydrolyzing all canonical (d)NTPs, as well as the mutagenic dUTP and 8-oxo-7,8-dihydro-2'-dGTP. However, this hydrolysis activity is diminished by the MtMazG[A219E] mutation. Moreover, deletion of mazG in M. smegmatis rendered the mycobacteria defective in response to oxidative stress. Importantly, expression of the wild-type MtMazG, but not the A219E mutant, restored cell viability under oxidative stress. Intriguingly, under oxidative stress, both the mazG-null and MtMazG[A219E]-expressing M. smegmatis strains failed to elevate relA, while retaining their ability to up-regulate sigE, suggesting a specific role for the MazG NTP-PPase activity in oxidative stress-triggered, transcriptional activation of relA. The MtMazG is a homotetramer with each subunit containing a single MazG core domain flanked by two regions, both of which are essential for NTP-PPase activity. Taken together, these results demonstrate that the mycobacterial MazG is a potent NTP-PPase and that this activity is required to maintain the full capacity of the mycobacteria to respond to oxidative stress. Our work implicates a role for the MazG activity in the virulence of M. tuberculosis. PMID:20529853

Lu, Liang-dong; Sun, Qing; Fan, Xiao-yong; Zhong, Yi; Yao, Yu-feng; Zhao, Guo-Ping

2010-09-01

157

Evidence of mycobacterial disease in COPD patients with lung volume reduction surgery; the importance of histological assessment of specimens: a cohort study  

Science.gov (United States)

Background Patients with COPD are at risk of non-tuberculous mycobacterial infection (NTM). This study examined the histology of lung tissue from COPD patients following lung volume reduction with particular focus on evidence of mycobacterial infection. Methods Retrospective histological study of 142 consecutive lung volume reduction surgical specimens (126 separate patients) at Royal Brompton Hospital between 2000 – 2013, with prospectively collected preoperative data on exacerbation rate, lung function and body mass index. Results 92% of patients had at least one other histological diagnosis in addition to emphysema. 10% of specimens had histological evidence of mycobacterial infection, one with co-existent aspergilloma. Mycobacteria were only identified in those patients with granulomas that were necrotising. These patients had higher exacerbation rates, lower TLCO and FEV1. Conclusion A proportion of severe COPD patients will have evidence of mycobacterial infection despite lack of clinical and radiological suspicion. This may have implications for long-term management of these patients. PMID:25086862

2014-01-01

158

Electrospray ionization-tandem mass spectrometry analysis of the mycolic acid profiles for the identification of common clinical isolates of mycobacterial species.  

Science.gov (United States)

Mycolic acids are unique and complex molecular structures found in mycobacterial species. In the present study, we investigated whether electrospray ionization-tandem mass spectrometry (ESI-MS/MS) can be used to identify mycobacterial species based on their mycolic acid profiles. Clinical isolates of Mycobacterium tuberculosis complex and 18 nontuberculosis mycobacterial (NTM) species identified by PCR-restriction fragment length polymorphism (RFLP) or real-time PCR were used for this analysis. Crude lipid extracts were prepared by saponifying 1-2 colonies of individual isolates of mycobacterial species and by chloroform and methanol (2:1, v/v) extraction. ESI-MS/MS in negative ion mode with high cone voltage and collision energy was used for mycolic acid profiling analysis. Combinatorial precursor ion scans of m/z 395, 367, and 339 in the range of m/z 1000-1400 resulted in spectra specific to individual mycobacteria. M. tuberculosis complex and M. pulveris showed major ions by performing precursor ion scans on m/z 395 and 367, while other NTM species showed major ions by performing scans on m/z 367 and 339. The different NTM species examined showed different species dependent mycolic acid profiles. In conclusion, we describe a rapid, reliable, and informative ESI-MS/MS protocol for mycolic acid profiling in mycobacterial species, which allows mycobacterial species to be easily identified in clinical laboratories. PMID:19318047

Song, Sang Hoon; Park, Kyoung Un; Lee, Jae Ho; Kim, Eui Chong; Kim, Jin Q; Song, Junghan

2009-05-01

159

Mycobacterial growth inhibition in murine splenocytes as a surrogate for protection against Mycobacterium tuberculosis (M. tb).  

Science.gov (United States)

Development of an improved vaccine against tuberculosis (TB) is hindered by the lack of a surrogate of protection. Efficacy of new TB vaccines in humans can only be evaluated by expensive and time consuming efficacy trials within TB endemic areas. It is critical that vaccines with the greatest potential to protect are selected for these trials. Mycobacterial growth inhibition assays (MGIAs) have been developed with the hope that these in-vitro functional assays will correlate with protection, which could aid in the selection of the best vaccine candidates. The present study describes the use of the BACTEC system to perform MGIAs in mice. We demonstrate reproducible mycobacterial growth inhibition in splenocytes from BCG immunised mice compared with unimmunised mice (P BACTEC MGIA can be used as a surrogate of protection in humans and preclinical animal models is now warranted. PMID:23726784

Marsay, Leanne; Matsumiya, Magali; Tanner, Rachel; Poyntz, Hazel; Griffiths, Kristin L; Stylianou, Elena; Marsh, Philip D; Williams, Ann; Sharpe, Sally; Fletcher, Helen; McShane, Helen

2013-09-01

160

Detection of Mycobacterium bovis and Mycobacterium tuberculosis from Cattle: Possible Public Health Relevance  

DEFF Research Database (Denmark)

Mycobacterium bovis and Mycobacterium tuberculosis infect both animals and humans. The disease epidemiology by these agents differs in developed and developing countries due to the differences in the implementation of the prevention and control strategies. The present study describes the detection of M. bovis and M. tuberculosis from specimens of lungs and pulmonary lymph nodes of four cattle died in an organized herd of 183 cattle in the state of Himachal Pradesh, India, with inconclusive skin test results. Identification and distinction of these closely related mycobacterial species was done by PCR-RFLP targeting hsp65 gene followed by spacer oligonucleotide typing. Mixed infection of M. bovis and M. tuberculosis was detected in one cattle.

Thakur, Aneesh

2012-01-01

 
 
 
 
161

Polyadenylylation in mycobacteria: evidence for oligo(dT)-primed cDNA synthesis.  

Science.gov (United States)

The ability of mRNA to direct synthesis of cDNA in the presence of oligo(dT) was analysed using a novel application of fluorescein-11-dUTP incorporation into cDNA by reverse transcriptase. Evidence is provided for the first time that a majority of the mycobacterial mRNA pool is polyadenylylated. mRNA transcripts of hsp65 were also amplified with specific primers from the oligo(dT)-primed cDNA preparation in Mycobacterium bovis BCG, M. smegmatis and M. vaccae. Furthermore, PCR amplication of cDNAs for genes entD, entC and trpE2 from M. bovis BCG yielded the expected products when reverse transcription was primed with oligo(dT), suggesting that polyadenylylation is a general phenomenon in mycobacteria. PMID:10746766

Adilakshmi, T; Ayling, P D; Ratledge, C

2000-03-01

162

Relief from Zmp1-Mediated Arrest of Phagosome Maturation Is Associated with Facilitated Presentation and Enhanced Immunogenicity of Mycobacterial Antigens?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pathogenic mycobacteria escape host innate immune responses by blocking phagosome-lysosome fusion. Avoiding lysosomal delivery may also be involved in the capacity of mycobacteria to evade major histocompatibility complex (MHC) class I- or II-dependent T-cell responses. In this study, we used a genetic mutant of Mycobacterium bovis BCG that is unable to escape lysosomal transfer and show that presentation of mycobacterial antigens is affected by the site of intracellular residence. Compared t...

Johansen, Pa?l; Fettelschoss, Antonia; Amstutz, Beat; Selchow, Petra; Waeckerle-men, Ying; Keller, Peter; Deretic, Vojo; Held, Leonhard; Ku?ndig, Thomas M.; Bo?ttger, Erik C.; Sander, Peter

2011-01-01

163

Indoleamine 2,3-Dioxygenase, Tryptophan Catabolism, and Mycobacterium avium subsp. paratuberculosis: a Model for Chronic Mycobacterial Infections ? †  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Virulent mycobacterial infections progress slowly, with a latent period that leads to clinical disease in a proportion of cases. Mycobacterium avium subsp. paratuberculosis is an intracellular pathogen that causes paratuberculosis or Johne's disease (JD), a chronic intestinal disease of ruminants. Indoleamine 2,3-dioxygenase (IDO), an enzyme that regulates tryptophan metabolism, was originally reported to have a role in intracellular pathogen killing and has since been shown to have an import...

Plain, Karren M.; Silva, Kumudika; Earl, John; Begg, Douglas J.; Purdie, Auriol C.; Whittington, Richard J.

2011-01-01

164

Lack of skin test reactivity to common mycobacterial antigens in human immunodeficiency virus infected individuals with high CD4 counts.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

BACKGROUND: T cell response to mycobacterial antigens may be directed against those antigens common to all mycobacteria (group i), those restricted to slow (group ii) or fast growers (group iii), or those which are species- or subspecies-specific (group iv). These responses were assessed by skin testing patients infected with the human immunodeficiency virus (HIV) and healthy controls with reagents derived from different strains of mycobacteria. METHODS: Skin test responses to new tuberculins...

Khoo, S. H.; Wilkins, E. G.; Fraser, I. S.; Hamour, A. A.; Stanford, J. L.

1996-01-01

165

In vivo repackaging of recombinant cosmid molecules for analyses of Salmonella typhimurium, Streptococcus mutans, and mycobacterial genomic libraries.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Strains of Escherichia coli K-12 were constructed that permitted the amplification of in vitro-packaged recombinant cosmid-transducing particles by in vivo repackaging of recombinant cosmid molecules. Thermal induction of these thermoinducible, excision-defective lysogens containing recombinant cosmid molecules yielded high titers of packaged recombinant cosmids and low levels of PFU. These strains were used to amplify packaged recombinant cosmid libraries of Mycobacterium leprae, Mycobacteri...

Jacobs, W. R.; Barrett, J. F.; Clark-curtiss, J. E.; Curtiss, R.

1986-01-01

166

Targeted delivery of mycobacterial antigens to human dendritic cells via Siglec-7 induces robust T cell activation.  

Science.gov (United States)

Lipids from mycobacteria can be presented to human T cells by group 1 CD1 Ag-presenting molecules (CD1a, CD1b, and CD1c). Group 1 CD1-restricted T cells are activated by lipid Ags presented by myeloid dendritic cells (DCs), after which they generate antibacterial effector functions, including IFN-? secretion and cytolysis. Thus, mycobacterial lipids are being investigated as components of novel vaccines for mycobacterial infections. In this study we show that the mycobacterial lipid Ag C80 glucose-6-monomycolate can be delivered to human CD1b(+) DCs via targeted liposomal nanoparticles, leading to robust group 1 CD1-restricted activation of T cells. Targeting was achieved by decorating the liposomes with a high-affinity glycan ligand of sialic acid-binding Ig-like lectin (Siglec)-7, a siglec receptor expressed on DCs that mediates rapid endocytosis and transport of its cargo to lysosomes. An Ab to Siglec-7 completely blocked the binding of targeted liposomes to human monocyte-derived DCs (Mo-DCs), demonstrating their targeting specificity. Mo-DCs pulsed with targeted liposomes containing C80 glucose-6-monomycolate more potently activated a CD1b-restricted T cell line relative to Mo-DCs pulsed with free lipid Ag or antigenic liposomes without Siglec-7 ligand. These data suggest that the endocytic function of Siglec-7 can be exploited to deliver glycolipid Ags to their target cell and increase the efficiency of display to T cells. PMID:25000981

Kawasaki, Norihito; Rillahan, Cory D; Cheng, Tan-Yun; Van Rhijn, Ildiko; Macauley, Matthew S; Moody, D Branch; Paulson, James C

2014-08-15

167

Anti-mycobacterial activity of root and leaf extracts of Anthocleista djalonensis (Loganiaceae and Diospyros mespiliformis (Ebenaceae  

Directory of Open Access Journals (Sweden)

Full Text Available We screened the aqueous and methanol leaf and root extracts of Anthocleista djalonensis, Diospyros mespiliformis, and their combinations for possible anti-mycobacterial activities using Mycobacterium smegmatis as a surrogate screen. These plants are reputed among folk practices as potent remedy in the management of tuberculosis and leprosy cases. In the sensitivity screening study, only the methanol extracts of A. djalonensis and D. mespiliformis showed anti-mycobacterial activity, while the aqueous extracts exhibited no inhibitory activity on M. smegmatis. The minimum inhibitory concentration (MIC of the methanol leaf and root extract of A. djalonensis against M. smegmatis were 125 ?g/ml. The MIC of the methanol leaf and root extracts of D. mespiliformis is 167 and 250 ?g/ml, respectively. In the interaction studies, four out of nine decimal combinations of the two medicinal plant extracts exhibited synergism with fractional inhibitory concentration indices < 1 and a negative activity index values. The 8:2 ratio of D. mespiliformis and A. djalonensis exhibited the greatest degree of antimycobacterial synergy against M. smegmatis. The result of this study supports the claims of efficacy reported in the folk use of these plants in mycobacterial infection and the plants could therefore be investigated further and harnessed as potent antimycobacterial agents.

Esimone Charles

2009-01-01

168

Molecular basis of mycobacterial lipid antigen presentation by CD1c and its recognition by ?? T cells.  

Science.gov (United States)

CD1c is a member of the group 1 CD1 family of proteins that are specialized for lipid antigen presentation. Despite high cell surface expression of CD1c on key antigen-presenting cells and the discovery of its mycobacterial lipid antigen presentation capability, the molecular basis of CD1c recognition by T cells is unknown. Here we present a comprehensive functional and molecular analysis of ?? T-cell receptor (TCR) recognition of CD1c presenting mycobacterial phosphomycoketide antigens. Our structure of CD1c with the mycobacterial phosphomycoketide (PM) shows similarities to that of CD1c-mannosyl-?1-phosphomycoketide in that the A' pocket accommodates the mycoketide alkyl chain; however, the phosphate head-group of PM is shifted ?6 Å in relation to that of mannosyl-?1-PM. We also demonstrate a bona fide interaction between six human TCRs and CD1c-mycoketide complexes, measuring high to moderate affinities. The crystal structure of the DN6 TCR and mutagenic studies reveal a requirement of five complementarity determining region (CDR) loops for CD1c recognition. Furthermore, mutagenesis of CD1c reveals residues in both the ?1 and ?2 helices involved in TCR recognition, yet not entirely overlapping among the examined TCRs. Unlike patterns for MHC I, no archetypical binding footprint is predicted to be shared by CD1c-reactive TCRs, even when recognizing the same or similar antigens. PMID:25298532

Roy, Sobhan; Ly, Dalam; Li, Nan-Sheng; Altman, John D; Piccirilli, Joseph A; Moody, D Branch; Adams, Erin J

2014-10-28

169

Modulation of naive CD4+ T-cell responses to an airway antigen during pulmonary mycobacterial infection.  

Science.gov (United States)

During pulmonary mycobacterial infection, there is increased trafficking of dendritic cells from the lungs to the draining lymph nodes. We hypothesized that ongoing mycobacterial infection would modulate recruitment and activation of antigen-specific naive CD4+ T cells after airway antigen challenge. BALB/c mice were infected by aerosol with Mycobacterium bovis BCG. At peak bacterial burden in the lungs (4 to 6 weeks postinfection), carboxy-fluorescein diacetate succinimidyl ester-labeled naive ovalbumin-specific DO11.10 T cells were adoptively transferred into infected and uninfected mice. Recipient mice were challenged intranasally with soluble ovalbumin (OVA), and OVA-specific T-cell responses were measured in the lungs, draining mediastinal lymph nodes (MLN), and spleens. OVA challenge resulted in increased activation and proliferation of OVA-specific T cells in the draining MLN of both infected and uninfected mice. However, only BCG-infected mice had prominent OVA-specific T-cell activation, proliferation, and Th1 differentiation in the lungs. BCG infection caused greater distribution of airway OVA to pulmonary dendritic cells and enhanced presentation of OVA peptide by lung CD11c+ cells. Together, these data suggest that an existing pulmonary mycobacterial infection alters the phenotype of lung dendritic cells so that they can activate antigen-specific naive CD4+ T cells in the lungs in response to airway antigen challenge. PMID:17296758

Anis, Mursalin M; Fulton, Scott A; Reba, Scott M; Harding, Clifford V; Boom, W Henry

2007-05-01

170

Mannan core branching of lipo(arabino)mannan is required for mycobacterial virulence in the context of innate immunity.  

Science.gov (United States)

The causative agent of tuberculosis (TB), Mycobacterium tuberculosis, remains an important worldwide health threat. Although TB is one of the oldest infectious diseases of man, a detailed understanding of the mycobacterial mechanisms underlying pathogenesis remains elusive. Here, we studied the role of the ?(1?2) mannosyltransferase MptC in mycobacterial virulence, using the Mycobacterium marinum zebrafish infection model. Like its M. tuberculosis orthologue, disruption of M. marinum mptC (mmar_3225) results in defective elongation of mannose caps of lipoarabinomannan (LAM) and absence of ?(1?2)mannose branches on the lipomannan (LM) and LAM mannan core, as determined by biochemical analysis (NMR and GC-MS) and immunoblotting. We found that the M. marinum mptC mutant is strongly attenuated in embryonic zebrafish, which rely solely on innate immunity, whereas minor virulence defects were observed in adult zebrafish. Strikingly, complementation with the Mycobacterium smegmatis mptC orthologue, which restored mannan core branching but not cap elongation, was sufficient to fully complement the virulence defect of the mptC mutant in embryos. Altogether our data demonstrate that not LAM capping, but mannan core branching of LM/LAM plays an important role in mycobacterial pathogenesis in the context of innate immunity. PMID:23902464

Stoop, Esther J M; Mishra, Arun K; Driessen, Nicole N; van Stempvoort, Gunny; Bouchier, Pascale; Verboom, Theo; van Leeuwen, Lisanne M; Sparrius, Marion; Raadsen, Susanne A; van Zon, Maaike; van der Wel, Nicole N; Besra, Gurdyal S; Geurtsen, Jeroen; Bitter, Wilbert; Appelmelk, Ben J; van der Sar, Astrid M

2013-12-01

171

Increased serum anti-mycobacterial antibody titers in rheumatoid arthritis patients: Is there any specific antigenic target?  

International Nuclear Information System (INIS)

Objective was to investigate the presence of immunoreactivity against mycobacterial antigens in the sera of patients with rheumatoid arthritis (Ra) and to detect the target of the immune reaction. This study was carried out on 60 patients with RA, and 25 patients with no joint diseases in the laboratory of Clinical Microbiology Department of Ankara University Medical Faculty, Ankara, Turkey between July 2003 to January 2004. Secreted and cellular antigens of Mycobacterium tuberculosis (M. tuberculosis) H37Rv and Mycobacterium bovis (M. bovis) were isolated and purified by high performance liquid chromatography to antigenic fractions. The immunoreactivity of patient and control sera against these antigens were determined by enzyme-linked immunosorbent assay (ELISA). Immunoreactivity against mycobacterial antigens in RA patients were significantly higher than controls. Significant difference between patients and controls has been determined with M. bovis Bacillus Calmette Guerin (BCG) culture fluid and sonicate antigens, but not with M. tuberculosis H37Rv. This suggests that the antigen triggering immune response in patients with RA may belong to or mainly expressed on M. bovis BCG. The ELISA results showed significant difference between RA patients and controls with all antigenic fractions. Presence of increased immunoreactivity against mycobacterial antigens in the sera of patients with RA was detected. When statistical analysis was considered, we cannot put forward ais was considered, we cannot put forward any antigenic fraction alone as the one responsible for the increased reactivity. (author)

172

Nontuberculous Mycobacterial (NTM) Disease in Immunocompetent Patients: Expanding Image Findings on Chest CT  

Energy Technology Data Exchange (ETDEWEB)

The aim of this study was to evaluate the chest CT features of nontuberculous mycobacterial (NTM) disease regardless of the specific organisms. This study included 74 consecutive patients (35 men, 39 women; mean age, 63 years; age range, 25-89 years) who were diagnosed with NTM disease according to the American Thoracic Society Guidelines (1997 and 2007) between January 2005 and July 2007. Chest CT images were randomly reviewed by two radiologists with consensus. The most common organism associated with NTM disease is M. avium-intracellulare complex (87.8%), followed by M. abscesses, M. kansasii, and M. chelonae. The most common chest CT finding was a nodular bronchiectatic lesion (n = 35, 46.7%), followed by a cavitary lesion of the upper lobe (n = 21, 28.0%), combined lesions of two prior subtypes (n = 6, 8.0%), consolidative lesion (s) (n = 5, 6.7%), a bronchogenic spreading pulmonary tuberculosis-like lesion (n = 5, 6.7%), a cavitary mass lesion with small satellite nodules (n = 2, 2.7%), and a miliary nodular lesion (n = 1, 1.3%). More than 5 segments were involved in 60 cases (81.1%). The nodular bronchiectatic lesion or cavitary lesion of upper lobe presents with multi-segmental involvement and the occurrence of combined consolidation is indicative of NTM disease

Shin, Hyo Hyun; Seon, Hyun Ju; Kim, Mok Hee; Choi, Song; Song, Sang Gook; Shin, Sang Soo; Kim, Yun Hyeon; Park, Jin Gyoon [Chonnam National University Hospital, Gwangju (Korea, Republic of)

2010-04-15

173

Pre-Columbian mycobacterial genomes reveal seals as a source of New World human tuberculosis.  

Science.gov (United States)

Modern strains of Mycobacterium tuberculosis from the Americas are closely related to those from Europe, supporting the assumption that human tuberculosis was introduced post-contact. This notion, however, is incompatible with archaeological evidence of pre-contact tuberculosis in the New World. Comparative genomics of modern isolates suggests that M. tuberculosis attained its worldwide distribution following human dispersals out of Africa during the Pleistocene epoch, although this has yet to be confirmed with ancient calibration points. Here we present three 1,000-year-old mycobacterial genomes from Peruvian human skeletons, revealing that a member of the M. tuberculosis complex caused human disease before contact. The ancient strains are distinct from known human-adapted forms and are most closely related to those adapted to seals and sea lions. Two independent dating approaches suggest a most recent common ancestor for the M. tuberculosis complex less than 6,000 years ago, which supports a Holocene dispersal of the disease. Our results implicate sea mammals as having played a role in transmitting the disease to humans across the ocean. PMID:25141181

Bos, Kirsten I; Harkins, Kelly M; Herbig, Alexander; Coscolla, Mireia; Weber, Nico; Comas, Iñaki; Forrest, Stephen A; Bryant, Josephine M; Harris, Simon R; Schuenemann, Verena J; Campbell, Tessa J; Majander, Kerttu; Wilbur, Alicia K; Guichon, Ricardo A; Wolfe Steadman, Dawnie L; Cook, Della Collins; Niemann, Stefan; Behr, Marcel A; Zumarraga, Martin; Bastida, Ricardo; Huson, Daniel; Nieselt, Kay; Young, Douglas; Parkhill, Julian; Buikstra, Jane E; Gagneux, Sebastien; Stone, Anne C; Krause, Johannes

2014-10-23

174

Models of the within-host dynamics of persistent mycobacterial infections.  

Science.gov (United States)

We use mathematical models to investigate the within-host dynamics of mycobacterial infections. In particular, we investigate the mechanisms by which bacteria such as Mycobacterium tuberculosis and Mycobacterium leprae persist at low densities for extended periods, and attain high densities much later. We suggest that the persistence of bacteria in face of immune pressure may result from the bacteria having a very slow growth rate, or having a dormant stage. We show that whereas these mechanisms may lead to long-term persistence, this will be obtained at relatively low densities. We then suggest that the long-term persistence of bacteria may result in the loss of immunity because of the deletion of specific T-cells arriving from the thymus, and the exhaustion of the specific T-cells as these cells reach the Hayflick limit and die. This loss of immunity will allow the bacteria to attain a high density. We propose experiments capable of testing our models and discuss the implications of the models for the treatment of infected hosts. PMID:8920248

Antia, R; Koella, J C; Perrot, V

1996-03-22

175

Revisiting tuberculous pleurisy: pleural fluid characteristics and diagnostic yield of mycobacterial culture in an endemic area  

Science.gov (United States)

Background Tuberculous pleurisy is traditionally indicated by extreme lymphocytosis in pleural fluid and low yield of effusion culture. However, there is considerable inconsistency among previous study results. In addition, these data should be updated due to early effusion studies and advances in culture methods. Methods From January 2004 to June 2009, patients with tuberculous pleurisy were retrospectively identified from the mycobacteriology laboratories and the pathology and tuberculosis registration databases of two hospitals in Taiwan where tuberculosis is endemic. Pleural fluid characteristics and yields of mycobacterial cultures using liquid media were evaluated. Results A total of 382 patients with tuberculous pleurisy were identified. The median lymphocyte percentage of total cells in pleural fluids was 84% (IQR 64–95%) and 17% of cases had a lymphocyte percentage of <50%. The lymphocyte percentage was negatively associated with the probability of a positive effusion culture (OR 0.97; 95% CI 0.96 to 0.99). The diagnostic yields were 63% for effusion culture, 48% for sputum culture, 79% for the combination of effusion and sputum cultures, and 74% for histological examination of pleural biopsy specimens. Conclusion The degree of lymphocyte predominance in tuberculous pleurisy was lower than was previously thought. The lymphocyte percentage in pleural fluid was negatively associated with the probability of a positive effusion culture. With the implementation of a liquid culture method, the sensitivity of effusion culture was much higher than has been previously reported, and the combination of effusion and sputum cultures provided a good diagnostic yield. PMID:22436167

Ruan, Sheng-Yuan; Chuang, Yu-Chung; Lin, Jou-Wei; Chien, Jung-Yien; Huang, Chun-Ta; Kuo, Yao-Wen; Lee, Li-Na; Yu, Chong-Jen J

2012-01-01

176

Interaction of alveolar epithelial cells with CFP21, a mycobacterial cutinase-like enzyme.  

Science.gov (United States)

Mycobacterium tuberculosis (M. tb), an intracellular pathogen, has the ability to infect alveolar epithelial cells (AEC) also in addition to alveolar macrophages. The virulence of M. tb is attributed to proteins encoded by genomic regions of deletion (RD) and till date 16 such regions (RD1-RD16) have been identified. Culture filtrate protein 21 (CFP21), a RD2 secretory protein, is a cutinase-like enzyme that possesses esterase and lipolytic activity. It is hypothesized that CFP21 could be playing a role in M. tb virulence by disrupting the host cell integrity. In this study, recombinant CFP21 was expressed and purified. The in vitro exposure of type I (WI26) and type II (A549) AEC to CFP21 resulted in a significant decline in their cellular viability by inducing cell apoptosis. However, the cytotoxic effects were more pronounced in WI26 cells than in A549 cells. The analysis of immune responses in CFP21-treated AEC exhibited significant production of reactive oxygen species and anti-inflammatory cytokine TGF-? which indicated oxidative stress-mediated cell death. These results show that CFP21 could play an important role in M. tb pathogenesis by disrupting the host alveolar barrier and thereby facilitating mycobacterial dissemination. PMID:25091806

Vir, Pooja; Gupta, Dheeraj; Agarwal, Ritesh; Verma, Indu

2014-11-01

177

Azithromycin blocks autophagy and may predispose cystic fibrosis patients to mycobacterial infection.  

Science.gov (United States)

Azithromycin is a potent macrolide antibiotic with poorly understood antiinflammatory properties. Long-term use of azithromycin in patients with chronic inflammatory lung diseases, such as cystic fibrosis (CF), results in improved outcomes. Paradoxically, a recent study reported that azithromycin use in patients with CF is associated with increased infection with nontuberculous mycobacteria (NTM). Here, we confirm that long-term azithromycin use by adults with CF is associated with the development of infection with NTM, particularly the multi-drug-resistant species Mycobacterium abscessus, and identify an underlying mechanism. We found that in primary human macrophages, concentrations of azithromycin achieved during therapeutic dosing blocked autophagosome clearance by preventing lysosomal acidification, thereby impairing autophagic and phagosomal degradation. As a consequence, azithromycin treatment inhibited intracellular killing of mycobacteria within macrophages and resulted in chronic infection with NTM in mice. Our findings emphasize the essential role for autophagy in the host response to infection with NTM, reveal why chronic use of azithromycin may predispose to mycobacterial disease, and highlight the dangers of inadvertent pharmacological blockade of autophagy in patients at risk of infection with drug-resistant pathogens. PMID:21804191

Renna, Maurizio; Schaffner, Catherine; Brown, Karen; Shang, Shaobin; Tamayo, Marcela Henao; Hegyi, Krisztina; Grimsey, Neil J; Cusens, David; Coulter, Sarah; Cooper, Jason; Bowden, Anne R; Newton, Sandra M; Kampmann, Beate; Helm, Jennifer; Jones, Andrew; Haworth, Charles S; Basaraba, Randall J; DeGroote, Mary Ann; Ordway, Diane J; Rubinsztein, David C; Floto, R Andres

2011-09-01

178

Expression and Immunogenicity of the Mycobacterial Ag85B/ESAT-6 Antigens Produced in Transgenic Plants by Elastin-Like Peptide Fusion Strategy  

Directory of Open Access Journals (Sweden)

Full Text Available This study explored a novel system combining plant-based production and the elastin-like peptide (ELP fusion strategy to produce vaccinal antigens against tuberculosis. Transgenic tobacco plants expressing the mycobacterial antigens Ag85B and ESAT-6 fused to ELP (TBAg-ELP were generated. Purified TBAg-ELP was obtained by the highly efficient, cost-effective, inverse transition cycling (ICT method and tested in mice. Furthermore, safety and immunogenicity of the crude tobacco leaf extracts were assessed in piglets. Antibodies recognizing mycobacterial antigens were produced in mice and piglets. A T-cell immune response able to recognize the native mycobacterial antigens was detected in mice. These findings showed that the native Ag85B and ESAT-6 mycobacterial B- and T-cell epitopes were conserved in the plant-expressed TBAg-ELP. This study presents the first results of an efficient plant-expression system, relying on the elastin-like peptide fusion strategy, to produce a safe and immunogenic mycobacterial Ag85B-ESAT-6 fusion protein as a potential vaccine candidate against tuberculosis.

Udo Conrad

2010-01-01

179

Coresistance to Isoniazid and Ethionamide Maps to Mycothiol Biosynthetic Genes in Mycobacterium bovis?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A search to identify new mechanisms of isoniazid resistance in Mycobacterium bovis led to the isolation of mutants defective in mycothiol biosynthesis due to mutations in genes coding for the glycosyltransferase (mshA) or the cysteine ligase (mshC). These mutants showed low-level resistance to isoniazid but were highly resistant to ethionamide. This study further illustrates that mutations in mycothiol biosynthesis genes may contribute to isoniazid or ethionamide resistance across mycobacteri...

Vilche?ze, Catherine; Av-gay, Yossef; Barnes, S. Whitney; Larsen, Michelle H.; Walker, John R.; Glynne, Richard J.; Jacobs, William R.

2011-01-01

180

Coresistance to isoniazid and ethionamide maps to mycothiol biosynthetic genes in Mycobacterium bovis.  

Science.gov (United States)

A search to identify new mechanisms of isoniazid resistance in Mycobacterium bovis led to the isolation of mutants defective in mycothiol biosynthesis due to mutations in genes coding for the glycosyltransferase (mshA) or the cysteine ligase (mshC). These mutants showed low-level resistance to isoniazid but were highly resistant to ethionamide. This study further illustrates that mutations in mycothiol biosynthesis genes may contribute to isoniazid or ethionamide resistance across mycobacterial species. PMID:21709101

Vilchèze, Catherine; Av-Gay, Yossef; Barnes, S Whitney; Larsen, Michelle H; Walker, John R; Glynne, Richard J; Jacobs, William R

2011-09-01

 
 
 
 
181

Towards new antituberculotic targets: biochemical characterisation of mycobacterial RNase E/G  

Directory of Open Access Journals (Sweden)

Full Text Available The World Health Organization estimates that each year 3 million people die from tuberculosis (TB and 8 million people become infected. No new anti-TB drugs have been introduced in the past 30 years, even though their development becomes increasingly important to face new challenges posed by multidrug-resistant and extensively drug-resistant strains and by acute infection with M. tuberculosis of HIV positive patients. Owing to its apparently important role in RNA metabolism, the RNase E/G family of endoribonucleases can be considered as a promising target for antimicrobial drugs. This consideration promted us to characterise biochemical properties of the M. tuberculosis RNase E/G homologue. To learn more about specific properties of RNase E/G homologues a M. tuberculosis RNase E/G (MycRne was overexpressed in E. coli and purified as a 6His-tagged polypeptide. To characterise MycRne, we used in vitro cleavage assays and primer extension analysis of total RNA extracted from mycobacteria. We show that affinity purified MycRne has an endoribonucleolytic activity, which is dependent on the 5'-phosphorylation status of RNA. We could also show that RNase E/G has Mg2+ dependent activity and similar to E. coli RNase E, MycRne was able to cleave in an intercistronic region of the putative 9S precursor of 5S rRNA. Although, similar to E. coli RNase E, the mycobacterial RNase E/G homologue plays a role in rRNA processing, the substrate specificities of these enzymes show differences. This suggests that RNase E/G can be used as a promising target for antimicrobial drugs that can be optimized to specifically target pathogenic species.

Agnes Csanadi

2008-06-01

182

Globally distributed mycobacterial fish pathogens produce a novel plasmid-encoded toxic macrolide, mycolactone F.  

Science.gov (United States)

Mycobacterium ulcerans and Mycobacterium marinum are closely related pathogens which share an aquatic environment. The pathogenesis of these organisms in humans is limited by their inability to grow above 35 degrees C. M. marinum causes systemic disease in fish but produces localized skin infections in humans. M. ulcerans causes Buruli ulcer, a severe human skin lesion. At the molecular level, M. ulcerans is distinguished from M. marinum by the presence of a virulence plasmid which encodes a macrolide toxin, mycolactone, as well as by hundreds of insertion sequences, particularly IS2404. There has been a global increase in reports of fish mycobacteriosis. An unusual clade of M. marinum has been reported from fish in the Red and Mediterranean Seas and a new mycobacterial species, Mycobacterium pseudoshottsii, has been cultured from fish in the Chesapeake Bay, United States. We have discovered that both groups of fish pathogens produce a unique mycolactone toxin, mycolactone F. Mycolactone F is the smallest mycolactone (molecular weight, 700) yet identified. The core lactone structure of mycolactone F is identical to that of M. ulcerans mycolactones, but a unique side chain structure is present. Mycolactone F produces apoptosis and necrosis on cultured cells but is less potent than M. ulcerans mycolactones. Both groups of fish pathogens contain IS2404. In contrast to M. ulcerans and conventional M. marinum, mycolactone F-producing mycobacteria are incapable of growth at above 30 degrees C. This fact is likely to limit their virulence for humans. However, such isolates may provide a reservoir for horizontal transfer of the mycolactone plasmid in aquatic environments. PMID:16923788

Ranger, Brian S; Mahrous, Engy A; Mosi, Lydia; Adusumilli, Sarojini; Lee, Richard E; Colorni, Angelo; Rhodes, Martha; Small, P L C

2006-11-01

183

Globally Distributed Mycobacterial Fish Pathogens Produce a Novel Plasmid-Encoded Toxic Macrolide, Mycolactone F?  

Science.gov (United States)

Mycobacterium ulcerans and Mycobacterium marinum are closely related pathogens which share an aquatic environment. The pathogenesis of these organisms in humans is limited by their inability to grow above 35°C. M. marinum causes systemic disease in fish but produces localized skin infections in humans. M. ulcerans causes Buruli ulcer, a severe human skin lesion. At the molecular level, M. ulcerans is distinguished from M. marinum by the presence of a virulence plasmid which encodes a macrolide toxin, mycolactone, as well as by hundreds of insertion sequences, particularly IS2404. There has been a global increase in reports of fish mycobacteriosis. An unusual clade of M. marinum has been reported from fish in the Red and Mediterranean Seas and a new mycobacterial species, Mycobacterium pseudoshottsii, has been cultured from fish in the Chesapeake Bay, United States. We have discovered that both groups of fish pathogens produce a unique mycolactone toxin, mycolactone F. Mycolactone F is the smallest mycolactone (molecular weight, 700) yet identified. The core lactone structure of mycolactone F is identical to that of M. ulcerans mycolactones, but a unique side chain structure is present. Mycolactone F produces apoptosis and necrosis on cultured cells but is less potent than M. ulcerans mycolactones. Both groups of fish pathogens contain IS2404. In contrast to M. ulcerans and conventional M. marinum, mycolactone F-producing mycobacteria are incapable of growth at above 30°C. This fact is likely to limit their virulence for humans. However, such isolates may provide a reservoir for horizontal transfer of the mycolactone plasmid in aquatic environments. PMID:16923788

Ranger, Brian S.; Mahrous, Engy A.; Mosi, Lydia; Adusumilli, Sarojini; Lee, Richard E.; Colorni, Angelo; Rhodes, Martha; Small, P. L. C.

2006-01-01

184

HspX-mediated protection against tuberculosis depends on its chaperoning of a mycobacterial molecule  

Science.gov (United States)

New approaches consisting of ‘multistage' vaccines against (TB) are emerging that combine early antigenic proteins with latency-associated antigens. In this study, HspX was tested for its potential to elicit both short- and long-term protective immune responses. HspX is a logical component in vaccine strategies targeting protective immune responses against primary infection, as well as against reactivation of latent infection, because as previously shown, it is produced during latency, and as our studies show, it elicits protection within 30 days of infection. Recent studies have shown that the current TB vaccine, bacilli Calmette-Guerin (BCG), does not induce strong interferon-? T-cell responses to latency-associated antigens like HspX, which may be in part why BCG fails to protect against reactivation disease. We therefore tested HspX protein alone as a prophylactic vaccine and as a boost to BCG vaccination, and found that HspX purified from M. tuberculosis cell lysates protected mice against aerosol challenge and improved the protective efficacy of BCG when used as a booster vaccine. Native HspX was highly immunogenic and protective, in a dose-dependent manner, in both short- and long-term infection models. Based on these promising findings, HspX was produced as a recombinant protein in E. coli, as this would enable facile purification; however, recombinant HspX (rHspX) alone consistently failed to protect against aerosol challenge. Incubation of rHspX with mycobacterial cell lysate and re-purification following incubation restored the capacity of the protein to confer protection. These data suggest the possibility that the native form may chaperone an immunogenic and protective antigen that is mycobacteria-specific. PMID:22801575

Taylor, Jennifer L; Wieczorek, Agatha; Keyser, Andrew R; Grover, Ajay; Flinkstrom, Rachel; Karls, Russell K; Bielefeldt-Ohmann, Helle; Dobos, Karen M; Izzo, Angelo A

2012-01-01

185

CT findings of mycobacterial infection other than tuberculosis : comparison with tuberculosis  

Energy Technology Data Exchange (ETDEWEB)

To compare the CT findings of mycobacterial infection other than tuberculosis (MOTT) with those of tuberculosis (TB). The chest CT scans of 30 immunocompetent patients with culture-proven pulmonary MOTT (M:F =3D 11:19; mean age, 51.2 yrs.) and of 24 patients with active tuberculosis (M:F 12:12; mean age, 42.5 yrs.) were analyzed by two radiologists; decisions were reached by consensus. Common findings for both MOTT and TB included brochogenically-spread bronchogenic spread nodular lesion (93.3% for MOTT, 100% for TB), bronchiectasis (90%, 83.3%), bronchial wall thickening (66.7%, 54.2%), granuloma (63.3%, 75%), parenchymal scarring (53.3%, 54.2%), and mediastinal lymphadenopathy (50%, 37.5%). Less commonly observed findings were emphysema (46.7%, 29.7%), atelectasis (36.7%, 29.2%), narrowing of a major airway (23.3%, 25%), consolidation (23.3%, 29.2%)and pleural disease (16.7%, 29.2%). Except for cavity (30%, 53.3%; P less than 0.05), the frequencies of each finding were not different between the two groups. A lobe-matched frequency comparison showed that only bronchiectasis in the right middle lobe (40%, 16.7%), right lower lobe (63.3%, 33.3%) and lingula division (53.3%, 25%) was significantly more common in MOTT than in TB (p less than 0.05). The number of lobes in which bronchiectasis and bronchial wall thickening were involved was greater in MOTT (3.20) than in TB (2.04) (p=3D 0.011). Although the CT findings of MOTT and TB overlap considerably, cavities are more common in TB, while in MOTT, bronchiectasis in the lower lung zone is more common and bronchiectasis tends to be more extensive. (author)

Yoon, Chang Jin; Goo, Jin Mo; Seo, Joon Beom; Kim, Se Hyung; Im, Jung Gi [College of Medicine and the Institute of Radiation Medicine, Seoul National University, Seoul (Korea, Republic of)

2000-03-01

186

CT findings of mycobacterial infection other than tuberculosis : comparison with tuberculosis  

International Nuclear Information System (INIS)

To compare the CT findings of mycobacterial infection other than tuberculosis (MOTT) with those of tuberculosis (TB). The chest CT scans of 30 immunocompetent patients with culture-proven pulmonary MOTT (M:F =3D 11:19); mean age, 51.2 yrs.) and of 24 patients with active tuberculosis (M:F 12:12; mean age, 42.5 yrs.) were analyzed by two radiologists; decisions were reached by consensus. Common findings for both MOTT and TB included brochogenically-spread bronchogenic spread nodular lesion (93.3% for MOTT, 100% for TB), bronchiectasis (90%, 83.3%), bronchial wall thickening (66.7%, 54.2%), granuloma (63.3%, 75%), parenchymal scarring (53.3%, 54.2%), and mediastinal lymphadenopathy (50%, 37.5%). Less commonly observed findings were emphysema (46.7%, 29.7%), atelectasis (36.7%, 29.2%), narrowing of a major airway (23.3%, 25%), consolidation (23.3%, 29.2%)and pleural disease (16.7%, 29.2%). Except for cavity (30%, 53.3%; P less than 0.05), the frequencies of each finding were not different between the two groups. A lobe-matched frequency comparison showed that only bronchiectasis in the right middle lobe (40%, 16.7%), right lower lobe (63.3%, 33.3%) and lingula division (53.3%, 25%) was significantly more common in MOTT than in TB (p less than 0.05). The number of lobes in which bronchiectasis and bronchial wall thickening were involved was greater in MOTT (3.20) than in TB (2.04) (p=3D 0.011). Although the CT findings of MOTT and TB overlap considerably, cavities are mor TB overlap considerably, cavities are more common in TB, while in MOTT, bronchiectasis in the lower lung zone is more common and bronchiectasis tends to be more extensive. (author)

187

Mycobacterial disease in cats in Great Britain: I. Culture results, geographical distribution and clinical presentation of 339 cases.  

Science.gov (United States)

This study investigated 339 cases of feline mycobacterial disease from cats with cutaneous lesions or masses found at exploratory laparotomy. Tissue samples were submitted to the Veterinary Laboratories Agency for mycobacterial culture over a 4-year period to December 2008. The study assessed which species of culturable mycobacteria were involved, where the cats lived, and their clinical presentation (physical findings, serum biochemistry, radiography, feline leukaemia virus and feline immunodeficiency virus status). Mycobacterium microti was cultured from 19%, Mycobacterium bovis 15%, Mycobacterium avium 7%, non-M avium non-tuberculous mycobacteria 6%, with no growth in 53% of samples. M microti, M bovis and M avium were found in almost mutually exclusive clusters within Great Britain (GB) (ie, M bovis in South-West England/Wales/Welsh Border, M avium in eastern England and M microti south of London and in South-West Scotland). While differences were seen in the clinical presentation and distribution of lesions caused by the different infections, these were not sufficiently different to be diagnostic. Cats commonly presented with single or multiple cutaneous lesions (74%), which were sometimes ulcerated or discharging, located most frequently on the head (54%). Lymph nodes were usually involved (47%); typically the submandibular nodes. Systemic or pulmonary signs were rarely seen (10-16%). When a cat is suspected of having mycobacteriosis, accurate identification of the species involved helps to determine appropriate action. Our findings show that knowing the cat's geographic location can be helpful, while the nature of the clinical presentation is less useful. Most cases of feline mycobacterial disease in GB are cutaneous. PMID:22079343

Gunn-Moore, Danièlle A; McFarland, Sarah E; Brewer, Jacqueline I; Crawshaw, Timothy R; Clifton-Hadley, Richard S; Kovalik, Marcel; Shaw, Darren J

2011-12-01

188

Mycobacterial Glycolipid Cord Factor Trehalose 6,6?-Dimycolate Causes a Decrease in Serum Cortisol during the Granulomatous Response  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Serum cortisol levels were evaluated in mice following intravenous administration of purified mycobacterial glycolipid trehalose 6,6?-dimycolate (TDM). C57BL/6 mice develop lung granulomas in response to TDM, while A/J mice are deficient in this process. Administration of TDM to C57BL/6 mice led to a rapid reduction in serum cortisol, concurrent with initiation of the granulomatous response and cytokine and chemokine mRNA induction. Cortisol levels were lowest on day 5 after TDM administrat...

Actor, Jeffrey K.; Indrigo, Jessica; Beachdel, Christopher M.; Olsen, Margaret; Wells, Alice; Hunter, Robert L.; Dasgupta, Amitava

2002-01-01

189

Mincle is essential for recognition and adjuvanticity of the mycobacterial cord factor and its synthetic analogue trehalose-dibehenate1  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The mycobacterial cord factor trehalose-6,6-dimycolate (TDM) and its synthetic analogue trehalose-6,6-dibehenate (TDB) are potent adjuvants for Th1/Th17 vaccination that activate Syk-Card9 signaling in antigen presenting cells. Here, we have further investigated the molecular mechanism of innate immune activation by TDM and TDB. The Syk-coupling adapter protein Fc receptor gamma chain (FcR?) was essential for macrophage activation and Th17 adjuvanticity. The FcR?-associated C-type lectin re...

Schoenen, Hanne; Bodendorfer, Barbara; Hitchens, Kelly; Manzanero, Silvia; Werninghaus, Kerstin; Nimmerjahn, Falk; Agger, Else Marie; Stenger, Steffen; Andersen, Peter; Ruland, Ju?rgen; Brown, Gordon D.; Wells, Christine; Lang, Roland

2010-01-01

190

Analytical Performance of the Roche LightCycler(R) Mycobacterium Detection Kit for the Diagnosis of Clinically Important Mycobacterial Species  

Science.gov (United States)

Background The LightCycler® Mycobacterium Detection Kit based on real-time PCR technology for the detection of Mycobacterium tuberculosis, Mycobacterium avium and Mycobacterium kansasii was recently developed. This study evaluated its analytical sensitivity, specificity and reproducibility. Methodology/Principal Findings Plasmid standards were prepared and used to determine the limit of detection. The assay was also performed against organisms other than mycobacteria, other mycobacterial strains and interfering substances to exclude cross-reactivity and interference. Reference standards were prepared and tested to assess the assay's reproducibility. All PCR assays were performed using the LightCycler® 2.0 Instrument. The detection limit for M. tuberculosis was 28 copies per microlitre. Neither cross-reactivity nor interference occurred with non-mycobacterial organisms and substances tested. Overall reproducibility for consecutive measurements, run-to-run, lot-to-lot, day-to-day and laboratory-to-laboratory achieved a coefficient of variance of less than two percent. Significance The LightCycler® Mycobacterium Detection kit has shown to be a robust and accurate assay with the potential to be used as a rapid TB diagnostic test. PMID:21961045

Omar, Shaheed V.; Roth, Andreas; Ismail, Nazir A.; Erasmus, Linda; Ehlers, Marthie; Kock, Marleen; Paulse, Nuraan; Said, Halima M.; Hoosen, Anwar A.; Reischl, Udo

2011-01-01

191

Tratamiento antirretroviral en pacientes con sida y micobacteriosis Anti-retroviral treatment in patients with AIDS and mycobacterial diseases  

Directory of Open Access Journals (Sweden)

Full Text Available La tuberculosis y otras micobacteriosis constituyen asociaciones o coinfecciones frecuentes en pacientes con sida y se asocian con una elevada mortalidad. En esta revisión se actualizan los tratamientos de las principales enfermedades micobacterianas asociadas al sida (tuberculosis y micobacteriosis por Mycobacterium avium, con especial énfasis en las interacciones farmacológicas entre antimicobacterianos, principalmente rifampicina y claritromicina, y fármacos antirretrovirales. Se analizan los esquemas de tratamiento, su duración, la quimioprofilaxis primaria y secundaria y el momento óptimo de iniciación del tratamiento antirretroviral. Finalmente se describe el síndrome inflamatorio de reconstitución inmune y su tratamiento.Tuberculosis and other mycobacterial diseases are frequent coinfections in AIDS patients with an increased related mortality. In this review we have updated the treatment of the main mycobacterial diseases (tuberculosis and Mycobacterium avium disease, under the scope of pharmacological interactions between antimycobacterial drugs, specially rifampicin and clarithromycin, and anti-retroviral drugs. Antimycobacterial treatment schemes, their duration, primary and secondary chemoprophylaxis and the optimal time to start the anti-retroviral therapy are analized. Finally, the immnune reconstitution inflammatory syndrome and its treatment are discussed.

Marcelo E. Corti

2005-08-01

192

Tratamiento antirretroviral en pacientes con sida y micobacteriosis / Anti-retroviral treatment in patients with AIDS and mycobacterial diseases  

Scientific Electronic Library Online (English)

Full Text Available SciELO Argentina | Language: Spanish Abstract in spanish La tuberculosis y otras micobacteriosis constituyen asociaciones o coinfecciones frecuentes en pacientes con sida y se asocian con una elevada mortalidad. En esta revisión se actualizan los tratamientos de las principales enfermedades micobacterianas asociadas al sida (tuberculosis y micobacteriosis [...] por Mycobacterium avium), con especial énfasis en las interacciones farmacológicas entre antimicobacterianos, principalmente rifampicina y claritromicina, y fármacos antirretrovirales. Se analizan los esquemas de tratamiento, su duración, la quimioprofilaxis primaria y secundaria y el momento óptimo de iniciación del tratamiento antirretroviral. Finalmente se describe el síndrome inflamatorio de reconstitución inmune y su tratamiento. Abstract in english Tuberculosis and other mycobacterial diseases are frequent coinfections in AIDS patients with an increased related mortality. In this review we have updated the treatment of the main mycobacterial diseases (tuberculosis and Mycobacterium avium disease), under the scope of pharmacological interaction [...] s between antimycobacterial drugs, specially rifampicin and clarithromycin, and anti-retroviral drugs. Antimycobacterial treatment schemes, their duration, primary and secondary chemoprophylaxis and the optimal time to start the anti-retroviral therapy are analized. Finally, the immnune reconstitution inflammatory syndrome and its treatment are discussed.

Marcelo E., Corti; Domingo J., Palmero.

193

TLR3 regulates mycobacterial RNA-induced IL-10 production through the PI3K/AKT signaling pathway.  

Science.gov (United States)

Cytokine induction in response to Mycobacterium tuberculosis (Mtb) infection is critical for pathogen control, by (i) mediating innate immune effector functions and (ii) instructing specific adaptive immunity. IL-10 is an important anti-inflammatory cytokine involved in pathogenesis of tuberculosis (TB). Here, we show that TLR3, a sensor of extracellular viral or host RNA with stable stem structures derived from infected or damaged cells, is essential for Mtb-induced IL-10 production. Upon Mycobacterium bovis Bacillus Calmette-Guérin (BCG) infection, TLR3(-/-) macrophages expressed lower IL-10 but higher IL-12p40 production, accompanied by reduced phosphorylation of AKT at Ser473. BCG-infected TLR3(-/-) mice exhibited reduced IL-10 but elevated IL-12 expression compared to controls. Moreover, higher numbers of splenic Th1 cells and reduced pulmonary bacterial burden and tissue damage were observed in BCG-infected TLR3(-/-) mice. Finally, BCG RNA induced IL-10 in macrophages via TLR3-mediated activation of PI3K/AKT. Our findings demonstrate a critical role of TLR3-mediated regulation in the pathogenesis of mycobacterial infection involving mycobacterial RNA, which induces IL-10 through the PI3K/AKT signaling pathway. PMID:24462705

Bai, Wenjuan; Liu, Haipeng; Ji, Qun; Zhou, Yilong; Liang, Le; Zheng, Ruijuan; Chen, Jianxia; Liu, Zhonghua; Yang, Hong; Zhang, Peng; Kaufmann, Stefan H E; Ge, Baoxue

2014-05-01

194

Combined Multilocus Short-Sequence-Repeat and Mycobacterial Interspersed Repetitive Unit-Variable-Number Tandem-Repeat Typing of Mycobacterium avium subsp. paratuberculosis Isolates? ‡  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Short-sequence-repeat (SSR) sequencing was applied to 127 Mycobacterium avium subsp. paratuberculosis isolates typed by mycobacterial interspersed repetitive unit-variable-number tandem repeats (MIRU-VNTR) and IS900 restriction fragment length polymorphism (RFLP). Combined MIRU-VNTR and SSR typing followed by secondary IS900 RFLP typing is an improved approach to high-resolution genotyping of this pathogen.

Thibault, Virginie C.; Grayon, Maggy; Boschiroli, Maria Laura; Willery, Eve; Allix-be?guec, Caroline; Stevenson, Karen; Biet, Franck; Supply, Philip

2008-01-01

195

Structural and functional characterization of an arylamine N-acetyltransferase from the pathogen Mycobacterium abscessus : differences from other mycobacterial isoforms and implications for selective inhibition  

DEFF Research Database (Denmark)

Mycobacterium abscessus is the most pathogenic rapid-growing mycobacterium and is one of the most resistant organisms to chemotherapeutic agents. However, structural and functional studies of M. abscessus proteins that could modify/inactivate antibiotics remain nonexistent. Here, the structural and functional characterization of an arylamine N-acetyltransferase (NAT) from M. abscessus [(MYCAB)NAT1] are reported. This novel prokaryotic NAT displays significant N-acetyltransferase activity towards aromatic substrates, including antibiotics such as isoniazid and p-aminosalicylate. The enzyme is endogenously expressed and functional in both the rough and smooth M. abscessus morphotypes. The crystal structure of (MYCAB)NAT1 at 1.8?Å resolution reveals that it is more closely related to Nocardia farcinica NAT than to mycobacterial isoforms. In particular, structural and physicochemical differences from other mycobacterial NATs were found in the active site. Peculiarities of (MYCAB)NAT1 were further supported by kinetic and docking studies showing that the enzyme was poorly inhibited by the piperidinol inhibitor of mycobacterial NATs. This study describes the first structure of an antibiotic-modifying enzyme from M. abscessus and provides bases to better understand the substrate/inhibitor-binding specificities among mycobacterial NATs and to identify/optimize specific inhibitors. These data should also contribute to the understanding of the mechanisms that are responsible for the pathogenicity and extensive chemotherapeutic resistance of M. abscessus.

Cocaign, Angélique; Kubiak, Xavier Jean Philippe

2014-01-01

196

Usefulness of Mycobacterial Interspersed Repetitive-Unit Locus PCR Amplification in Rapid Diagnosis of Beijing Lineage Strain Infection among Pediatric Tuberculosis Patients?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We assessed the usefulness of mycobacterial interspersed repetitive-unit–variable-number tandem-repeat loci 26, 31, ETR-A, Mtub30, and Mtub02 and a deletion-targeted multiplex PCR in identifying pediatric Mycobacterium tuberculosis Beijing lineage strain infection. We found that the Beijing lineage isolates accounted for ?62% (130/210) of the study isolates.

Liu, Ruixi; Xing, Linlin; Peng, Ze; Zhang, Yukun; Zhu, Chaomin; Yang, Zhenhua

2011-01-01

197

Efficient method for mycobacterial DNA extraction in blood cultures aids rapid PCR identification of Mycobacterium tuberculosis and Mycobacterium avium.  

Science.gov (United States)

The study presented here evaluated the utility of several methods of extracting mycobacterial nucleic acids from positive blood culture samples and examined the effect of each method on the performance of an in-house PCR used directly in the peripheral blood of 80 patients with AIDS to identify Mycobacterium spp. The modified Boom method for extracting DNA from blood cultures proved to be the most efficient, with subsequent PCR analysis yielding 100% positivity (7 samples positive for M. avium and 5 for M. tuberculosis). Only three of 12 patients with a positive blood culture had a PCR result positive for M. avium in peripheral blood. The identification of mycobacteria by PCR in blood culture took about 3 days, reducing the time to diagnosis by several weeks. These results demonstrate that PCR is a sensitive and quick method for identifying mycobacteria, especially when a good DNA extraction method is applied. PMID:15558344

Nakatani, S M; Burger, M; Assef, M C; Brockelt, S R; Cogo, L L; Messias-Reason, I J T

2004-11-01

198

Techniques of DNA hybridization detect small numbers of mycobacteria with no cross-hybridization with non-mycobacterial respiratory organisms  

International Nuclear Information System (INIS)

The traditional methods used in identifying mycobacteria, such as acid-fast bacillus stains and culture, are often time-consuming, insensitive, and nonspecific. As part of an ongoing program to improve diagnosis and characterization of mycobacteria, the authors have found that deoxyribonucleic acid (DNA) hybridization techniques using isotopically labeled, single-stranded, total DNA can be used to detect as little as 10(-4) micrograms of Mycobacterium tuberculosis (MTb) DNA. This amount of DNA represents approximately 2 X 10(4) genomes. They have also shown the MTb DNA is sufficiently different from the DNA of non-mycobacterial microorganisms such that cross-hybridization with MTb DNA does not occur under the hybridization conditions employed. The authors speculate that DNA hybridization techniques may allow the rapid, sensitive, and specific identification of mycobacteria

199

[Implementation of the technical requirements of the UNE-EN-ISO 15189 quality standard in a mycobacterial laboratory].  

Science.gov (United States)

The UNE-EN-ISO 15189:2007 standard defines the requirements for quality and competence that must be met by medical laboratories. These laboratories should use this international standard to develop their own quality management systems and to evaluate their own competencies; in turn, this standard will be used by accreditation bodies to confirm or recognize the laboratories' competence. In clinical microbiology laboratories, application of the standard implies the implementation of the technical and specific management requirements that must be met to achieve optimal quality when carrying out microbiological tests. In Spain, accreditation is granted by the Spanish Accreditation Body (Entidad Nacional de Acreditación). This review aims to discuss the practical application of the standard's technical requirements in mycobacterial laboratory. Firstly, we define the scope of accreditation. Secondly, we specify how the items of the standard on personnel management, control of equipment, environmental facilities, method validation, internal controls and customer satisfaction surveys were developed and implemented in our laboratory. PMID:23453231

Guna Serrano, M del Remedio; Ocete Mochón, M Dolores; Lahiguera, M José; Bresó, M Carmen; Gimeno Cardona, Concepción

2013-02-01

200

The role of the mycobacterial DNA-binding protein 1 (MDP1 from Mycobacterium bovis BCG in host cell interaction  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Mycobacterium tuberculosis differs from most pathogens in its ability to multiply inside monocytes and to persist during long periods of time within granuloma in a status of latency. A class of proteins called mycobacterial histone-like proteins has been associated with regulation of replication and latency, but their precise role in the infection process has yet to be uncovered. Our study aimed at defining the impact of the histone-like protein MDP1 from M. bovis BCG (mycobacterial DNA-binding protein 1, corresponding to Rv2986c from M. tuberculosis on early steps of infection. Results Previously, a BCG (Bacillus Calmette Guérin strain had been generated by antisense-technique exhibiting reduced MDP1 expression. This strain was now used to analyse the impact of reduced amount of MDP1 on the interaction with human blood monocytes, macrophage lines and PBMC (peripheral blood mononuclear cells. MDP1 was revealed to be required for growth at acidic pH and for intracellular replication in human blood monocytes. Down-regulation of MDP1 resulted in reduced secretion of the cytokine IL-1? by infected human PBMC. In addition, a reduction of MDP1 expression had a major impact on the formation of fused multi-nucleated macrophages. In monocyte preparations from human blood as well as in human and mouse macrophage cell lines, both the percentage of multi-nucleated cells and the number of nuclei per cell were much enhanced when the monocytes were infected with BCG expressing less MDP1. Conclusion MDP1 from M. bovis BCG affects the growth at acidic pH and the intracellular replication in human monocytes. It furthermore affects cytokine secretion by host cells, and the formation of fused multi-nucleated macrophages. Our results suggest an important role of MDP1 in persistent infection.

Kunisch Ralph

2012-08-01

 
 
 
 
201

Homing events in the gyrA gene of some mycobacteria.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The A subunit of DNA gyrase in Mycobacterium leprae, unlike its counterpart in Mycobacterium tuberculosis, is produced by protein splicing as its gene, gyrA, harbors a 1260-bp in-frame insertion encoding an intein, a putative homing endonuclease. Analysis of the gyrA locus from different mycobacterial species revealed the presence of inteins in Mycobacterium flavescens, Mycobacterium gordonae and Mycobacterium kansasii but not in 10 other pathogenic or saprophytic mycobacteria. In all four ca...

Fsihi, H.; Vincent, V.; Cole, S. T.

1996-01-01

202

Successful treatment of refractory cutaneous infection caused by Mycobacterium marinum with a combined regimen containing amikacin  

Directory of Open Access Journals (Sweden)

Full Text Available Yingxue Huang,* Xiulian Xu,* Yi Liu, Kan Wu, Wei Zhang, Pai Liu, Xuesi Zeng, Jianfang Sun, Yiqun Jiang, Hongsheng WangKey Laboratory of Molecular Biology for Skin Diseases, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China *These authors contributed equally to this workBackground: The incidence of Mycobacterium marinum infection has been increasing. First-line antituberculous drugs and other common antibiotics are effective for most cutaneous M. marinum infections; however, treatment failure still occurs in some rare cases. We report a case of a 70-year-old man with refractory cutaneous infection caused by M. marinum. Reasons for delayed diagnosis and related factors of the refractory infection are also discussed.Methods: Samples of lesional skin were inoculated on Löwenstein–Jensen medium for acid-fast bacilli. Species of mycobacterium were identified by polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP analysis. We then carried out genotyping by using mycobacterial interspersed repetitive units and sequencing of heat shock protein 65 (hsp65 and 16S rDNA genes.Results: Tissue cultures for acid-fast bacilli were positive. PCR-RFLP analysis and sequencing of hsp65 and 16S rDNA genes confirmed the isolated organisms to be M. marinum. Systemic therapy with rifampicin, clarithromycin, and amikacin empirically over 6 months led to complete resolution of skin lesions leaving only some residual scars.Conclusion: Key diagnostic elements for M. marinum infections include a high index of suspicion raised by chronic lesions, poor response to conventional treatments, and a history of fish-related exposure. Strong clinical suggestion of M. marinum infection warrants initial empirical treatment. The duration of therapy is usually several months or even longer, especially for elderly patients. Amikacin can be considered in multidrug therapy for treatment of some refractory M. marinum infections.Keywords: amikacin, clarithromycin, skin infection, Mycobacterium marinum, nontuberculous mycobacteria

Sun J

2012-11-01

203

Transcriptional profiling of mycobacterial antigen-induced responses in infants vaccinated with BCG at birth  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Novel tuberculosis (TB vaccines recently tested in humans have been designed to boost immunity induced by the current vaccine, Mycobacterium bovis Bacille Calmette-Guérin (BCG. Because BCG vaccination is used extensively in infants, this population group is likely to be the first in which efficacy trials of new vaccines will be conducted. However, our understanding of the complexity of immunity to BCG in infants is inadequate, making interpretation of vaccine-induced immune responses difficult. Methods To better understand BCG-induced immunity, we performed gene expression profiling in five 10-week old infants routinely vaccinated with BCG at birth. RNA was extracted from 12 hour BCG-stimulated or purified protein derivative of tuberculin (PPD-stimulated PBMC, isolated from neonatal blood collected 10 weeks after vaccination. RNA was hybridised to the Sentrix® HumanRef-8 Expression BeadChip (Illumina to measure expression of >16,000 genes. Results We found that ex vivo stimulation of PBMC with PPD and BCG induced largely similar gene expression profiles, except that BCG induced greater macrophage activation. The peroxisome proliferator-activated receptor (PPAR signaling pathway, including PPAR-?, involved in activation of the alternative, anti-inflammatory macrophage response was down-regulated following stimulation with both antigens. In contrast, up-regulation of genes associated with the classic, pro-inflammatory macrophage response was noted. Further analysis revealed a decrease in the expression of cell adhesion molecules (CAMs, including integrin alpha M (ITGAM, which is known to be important for entry of mycobacteria into the macrophage. Interestingly, more leukocyte genes were down-regulated than up-regulated. Conclusion Our results suggest that a combination of suppressed and up-regulated genes may be key in determining development of protective immunity to TB induced by vaccination with BCG.

Hill Adrian VS

2009-02-01

204

Potential of mycobacterial excretory secretory protein antigens (sevatb ES-31, ES-43, EST-6 and ES-20) as biomarkers to detect Mycobacterium tuberculosis bacilli  

Digital Repository Infrastructure Vision for European Research (DRIVER)

There is a need for a simple and reliable method to identify Mycobacterium tuberculosis from nontuberculous mycobacteria (NTM). The utility of mycobacterial ES-31, ES-43, EST-6 or ES-20 antigen as a biomarker for differentiation of Mycobacterium tuberculosis bacilli from nontuberculous mycobacteria was explored using Fluorescein isothiocyanate conjugated antibodies against these antigens. Detection of these antigens was done from M.tb H37Ra and H37Rv DSS antigen. The presence of antigen in ba...

Anindita, M.; Thamke, D.; Mendiratta, D. K.; Harinath, B. C.

2010-01-01

205

Differentiation of Mycobacterium tuberculosis Complex and Nontuberculous Mycobacterial Liquid Cultures by Using Peptide Nucleic Acid-Fluorescence In Situ Hybridization Probes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A blinded comparison of peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH) with routine identification methods was performed on 74 consecutively positive mycobacterial liquid cultures. All Mycobacterium tuberculosis cultures (48 of 48) and 22 of 27 (81.5%) nontuberculous cultures were correctly identified (including one mixed culture). Five isolates yielded no reaction with either probe and were identified as Mycobacterium xenopi, Mycobacterium fortuitum, or Mycobacterium flav...

Drobniewski, F. A.; More, P. G.; Harris, G. S.

2000-01-01

206

Automated High-Throughput Mycobacterial Interspersed Repetitive Unit Typing of Mycobacterium tuberculosis Strains by a Combination of PCR and Nondenaturing High-Performance Liquid Chromatography  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) typing of Mycobacterium tuberculosis complex isolates is portable, 100% reproducible, and highly discriminatory. Nondenaturing high-performance liquid chromatography (non-dHPLC) with use of a WAVE microbial analysis system is a promising method of PCR amplicon analysis as it is low cost and requires no preanalysis processing. The aims of this study were to validate the application of WAVE microbial analysis s...

Evans, Jason T.; Hawkey, Peter M.; Smith, E. Grace; Boese, Kerstin A.; Warren, Roderic E.; Hong, George

2004-01-01

207

MmpL11 protein transports mycolic acid-containing lipids to the mycobacterial cell wall and contributes to biofilm formation in Mycobacterium smegmatis.  

Science.gov (United States)

A growing body of evidence indicates that MmpL (mycobacterial membrane protein large) transporters are dedicated to cell wall biosynthesis and transport mycobacterial lipids. How MmpL transporters function and the identities of their substrates have not been fully elucidated. We report the characterization of Mycobacterium smegmatis MmpL11. We showed previously that M. smegmatis lacking MmpL11 has reduced membrane permeability that results in resistance to host antimicrobial peptides. We report herein the further characterization of the M. smegmatis mmpL11 mutant and identification of the MmpL11 substrates. We found that biofilm formation by the M. smegmatis mmpL11 mutant was distinct from that by wild-type M. smegmatis. Analysis of cell wall lipids revealed that the mmpL11 mutant failed to export the mycolic acid-containing lipids monomeromycolyl diacylglycerol and mycolate ester wax to the bacterial surface. In addition, analysis of total lipids indicated that the mycolic acid-containing precursor molecule mycolyl phospholipid accumulated in the mmpL11 mutant compared with wild-type mycobacteria. MmpL11 is encoded at a chromosomal locus that is conserved across pathogenic and nonpathogenic mycobacteria. Phenotypes of the M. smegmatis mmpL11 mutant are complemented by the expression of M. smegmatis or M. tuberculosis MmpL11, suggesting that MmpL11 plays a conserved role in mycobacterial cell wall biogenesis. PMID:23836904

Pacheco, Sophia A; Hsu, Fong-Fu; Powers, Katelyn M; Purdy, Georgiana E

2013-08-16

208

Assembly and proteolytic processing of mycobacterial ClpP1 and ClpP2  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Caseinolytic proteases (ClpPs) are barrel-shaped self-compartmentalized peptidases involved in eliminating damaged or short-lived regulatory proteins. The Mycobacterium tuberculosis (MTB) genome contains two genes coding for putative ClpPs, ClpP1 and ClpP2 respectively, that are likely to play a role in the virulence of the bacterium. Results We report the first biochemical characterization of ClpP1 and ClpP2 peptidases from MTB. Bot...

2011-01-01

209

Identification of non-tuberculous mycobacteria from the Central Public Health Laboratory from Mato Grosso do Sul and analysis of clinical relevance Identificação de micobactérias não-tuberculosas do Laboratório Central de Saúde Pública de Mato Grosso de Sul e análise de dados clínicos dos pacientes  

Directory of Open Access Journals (Sweden)

Full Text Available Non-tuberculous mycobacteria isolated at the Central Public Health Laboratory from Mato Grosso do Sul in 2003 and 2004 were identified by conventional phenotypic methods (TI and by PCR-Restriction Enzyme Analysis (PRA using the hsp65 gene as target (PRA-hsp65. With 15 of the 32 analysed isolates, results of both methods were concordant, being 8 Mycobacterium avium, 3 M. fortutium, 1 M. kansasii, 1 M. flavescens, 1 M. peregrinum and 1 Nocardia brasiliensis. TI of 12 isolates was inconclusive. Novel PRA-hsp65 patterns were observed with 11 isolates. Medical data were evaluated for inference of clinical relevance of these isolates.Micobactérias não-tuberculosas isoladas no Laboratório Central de Saúde Pública de Mato Grosso do Sul em 2003 e 2004 foram identificadas usando métodos fenotípicos convencionais (TI e PCR-Restriction Enzyme Analysis (PRA tendo o gene hsp65 como alvo (PRA-hsp65. Em 15 dos 32 isolados analisados os resultados obtidos com ambos métodos foram concordantes, sendo 8 Mycobacterium avium, 3 M. fortutium, 1 M. kansasii, 1 M. flavescens, 1 M. peregrinum e 1 Nocardia brasiliensis. TI de 12 isolados não foi conclusiva. Perfis não descritos de PRA-hsp65 foram observados com 11 isolados. Dados dos prontuários médicos foram avaliados para inferir a relevância clínica dos isolados.

Paulo Ricardo de Souza Moraes

2008-06-01

210

Identification of non-tuberculous mycobacteria from the Central Public Health Laboratory from Mato Grosso do Sul and analysis of clinical relevance / Identificação de micobactérias não-tuberculosas do Laboratório Central de Saúde Pública de Mato Grosso de Sul e análise de dados clínicos dos pacientes  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Micobactérias não-tuberculosas isoladas no Laboratório Central de Saúde Pública de Mato Grosso do Sul em 2003 e 2004 foram identificadas usando métodos fenotípicos convencionais (TI) e PCR-Restriction Enzyme Analysis (PRA) tendo o gene hsp65 como alvo (PRA-hsp65). Em 15 dos 32 isolados analisados os [...] resultados obtidos com ambos métodos foram concordantes, sendo 8 Mycobacterium avium, 3 M. fortutium, 1 M. kansasii, 1 M. flavescens, 1 M. peregrinum e 1 Nocardia brasiliensis. TI de 12 isolados não foi conclusiva. Perfis não descritos de PRA-hsp65 foram observados com 11 isolados. Dados dos prontuários médicos foram avaliados para inferir a relevância clínica dos isolados. Abstract in english Non-tuberculous mycobacteria isolated at the Central Public Health Laboratory from Mato Grosso do Sul in 2003 and 2004 were identified by conventional phenotypic methods (TI) and by PCR-Restriction Enzyme Analysis (PRA) using the hsp65 gene as target (PRA-hsp65). With 15 of the 32 analysed isolates, [...] results of both methods were concordant, being 8 Mycobacterium avium, 3 M. fortutium, 1 M. kansasii, 1 M. flavescens, 1 M. peregrinum and 1 Nocardia brasiliensis. TI of 12 isolates was inconclusive. Novel PRA-hsp65 patterns were observed with 11 isolates. Medical data were evaluated for inference of clinical relevance of these isolates.

Paulo Ricardo de Souza, Moraes; Erica, Chimara; Maria Alice da Silva, Telles; Suely Yoko Misuka, Ueki; Eunice Atsuko Totumi, Cunha; Michael Robin, Honer; Sylvia Cardoso, Leão.

2008-06-01

211

Identification of non-tuberculous mycobacteria from the Central Public Health Laboratory from Mato Grosso do Sul and analysis of clinical relevance / Identificação de micobactérias não-tuberculosas do Laboratório Central de Saúde Pública de Mato Grosso de Sul e análise de dados clínicos dos pacientes  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Micobactérias não-tuberculosas isoladas no Laboratório Central de Saúde Pública de Mato Grosso do Sul em 2003 e 2004 foram identificadas usando métodos fenotípicos convencionais (TI) e PCR-Restriction Enzyme Analysis (PRA) tendo o gene hsp65 como alvo (PRA-hsp65). Em 15 dos 32 isolados analisados os [...] resultados obtidos com ambos métodos foram concordantes, sendo 8 Mycobacterium avium, 3 M. fortutium, 1 M. kansasii, 1 M. flavescens, 1 M. peregrinum e 1 Nocardia brasiliensis. TI de 12 isolados não foi conclusiva. Perfis não descritos de PRA-hsp65 foram observados com 11 isolados. Dados dos prontuários médicos foram avaliados para inferir a relevância clínica dos isolados. Abstract in english Non-tuberculous mycobacteria isolated at the Central Public Health Laboratory from Mato Grosso do Sul in 2003 and 2004 were identified by conventional phenotypic methods (TI) and by PCR-Restriction Enzyme Analysis (PRA) using the hsp65 gene as target (PRA-hsp65). With 15 of the 32 analysed isolates, [...] results of both methods were concordant, being 8 Mycobacterium avium, 3 M. fortutium, 1 M. kansasii, 1 M. flavescens, 1 M. peregrinum and 1 Nocardia brasiliensis. TI of 12 isolates was inconclusive. Novel PRA-hsp65 patterns were observed with 11 isolates. Medical data were evaluated for inference of clinical relevance of these isolates.

Paulo Ricardo de Souza, Moraes; Erica, Chimara; Maria Alice da Silva, Telles; Suely Yoko Misuka, Ueki; Eunice Atsuko Totumi, Cunha; Michael Robin, Honer; Sylvia Cardoso, Leão.

212

Rapid detection and identification of nontuberculous mycobacterial pathogens in fish by using high-resolution melting analysis.  

Science.gov (United States)

Mycobacterial infections in fish are commonly referred to as piscine mycobacteriosis, irrespectively of the specific identity of the causal organism. They usually cause a chronic disease and sometimes may result in high mortalities and severe economic losses. Nearly 20 species of Mycobacterium have been reported to infect fish. Among them, Mycobacterium marinum, M. fortuitum, and M. chelonae are generally considered the major agents responsible for fish mycobacteriosis. As no quick and inexpensive diagnostic test exists, we tested the potential of high-resolution melting analysis (HRMA) to rapidly identify and differentiate several Mycobacterium species involved in fish infections. By analyzing both the melting temperature and melting profile of the 16S-23S rRNA internal transcribed spacer (ITS), we were able to discriminate 12 different species simultaneously. Sensitivity tests conducted on purified M. marinum and M. fortuitum DNA revealed a limit of detection of 10 genome equivalents per reaction. The primers used in this procedure did not lead to any amplification signal with 16 control non-Mycobacterium species, thereby demonstrating their specificity for the genus Mycobacterium. PMID:24123734

Phung, Thu Nguyet; Caruso, Domenico; Godreuil, Sylvain; Keck, Nicolas; Vallaeys, Tatiana; Avarre, Jean-Christophe

2013-12-01

213

Characterization of Clonal Complexity in Tuberculosis by Mycobacterial Interspersed Repetitive Unit-Variable-Number Tandem Repeat Typing  

Science.gov (United States)

In recent years, the application of molecular tools has shown us that clonal complexity in infection by Mycobacterium tuberculosis is not anecdotal. Exogenous reinfections, mixed infections, compartmentalization, and microevolution are different aspects of this issue. The detection and characterization of clonal variants of M. tuberculosis by standard genotyping methods is laborious and frequently requires expertise. Our aim was to evaluate a new genotyping PCR-based method for M. tuberculosis, mycobacterial interspersed repetitive unit-variable-number tandem repeat typing (MIRU-VNTR), as a potential tool to simplify and optimize the clonal analysis of tuberculosis. MIRU-VNTR was able to detect mixed clonal variants in vitro, even for clones at low ratios (1:99). This technique was prospectively applied to search for cases infected by more than one clone. Clonal variants within the same host were detected in 3 out of 115 cases (2.6%), including cases with clones which were indistinguishable by restriction fragment length polymorphism or spoligotyping. In one case, coinfecting clonal variants differed in antibiotic susceptibilities. MIRU-VNTR was applied to cases with proven polyclonal infection, and it succeeded in detecting the coinfecting strains and proved useful in confirming cases of compartmentalized infection. MIRU-VNTR is a simple, rapid, and sensitive method which could facilitate and optimize the identification and characterization of clonal complexity in M. tuberculosis infection. PMID:16272501

Garcia de Viedma, Dario; Alonso Rodriguez, Noelia; Andres, Sandra; Ruiz Serrano, Maria Jesus; Bouza, Emilio

2005-01-01

214

Evaluation of bone marrow and blood cultures for the recovery of mycobacteria in the diagnosis of disseminated mycobacterial infections.  

Science.gov (United States)

This study evaluated the validity of bone marrow (BM) and blood specimens for the diagnosis of disseminated mycobacterial infections (DMIs). From 1990 to February 1997, all specimens were processed with the lysis-centrifugation procedure; thereafter (until December 2001), they were processed with the BACTEC Myco/F Lytic system. Twenty-three paired BM-blood specimens with mycobacteria in at least one specimen were studied from 23 patients. The strains isolated were 14 Mycobacterium avium complex (MAC) and nine M. tuberculosis complex (MTBC). Blood specimens had a statistically significant greater sensitivity for the isolation of MAC than BM (100% vs. 57.1%, respectively), whereas sensitivity for the isolation of MTBC was equal for the two specimen types (66.7%). Although not statistically significant, the times required to detect mycobacteria from blood specimens were lower than those from BM in the MycoF/Lytic system. Overall, blood cultures represented a more sensitive and less invasive alternative to BM cultures for the diagnosis of disseminated mycobacteriosis caused by MAC, especially when the MycoF/Lytic system was used, but provided no advantage for the diagnosis of DMI caused by MTBC. PMID:15301676

Pacios, E; Alcalá, L; Ruiz-Serrano, M J; de Viedma, D G; Rodríguez-Créixems, M; Marín-Arriaza, M; Berenguer, J; Bouza, E

2004-08-01

215

Progressing features of atypical mycobacterial infection in the lung on conventional and high resolution CT (HRCT) images  

International Nuclear Information System (INIS)

The aim of this study was to clarify the localization of abnormalities within secondary pulmonary lobules and the changes in follow-up studies of pulmonary atypical mycobacterial infection (AMI) by conventional and high-resolution computed tomography (HRCT). Forty-six patients (16 men and 30 women; 43-84 years) with pulmonary AMI (M. intracellulare 36; M. avium 10) in the lung were examined by conventional and HRCT. In peripheral zones, all patients had the nodule located in the terminal or lobular bronchiole, and most of the patients also had nodules accompanied with a wedge-shaped or linear shadow connected with the pleura. In the follow-up scans, new centrilobular nodules appeared in other segments, and consolidation or ground-glass pattern appeared newly and was preceded by nodules. Bronchiectasis became more severe in five of 38 follow-up patients. The common HRCT findings of AMI were centrilobular, peribronchovascular nodules, bronchiectasis, consolidation, and pleural thickening/adhesion. The nodules frequently connected with the pleura. The initial and follow-up studies suggest that the disease may begin in the terminal bronchiole or as preexisting bronchiectasis and spread transbronchially along the draining bronchus or towards the pleura to produce lesions such as new nodules, cavities, consolidation, pleuritis, and bronchiectasis, or more severe bronchiectasis. (author)

216

Specific Interaction between Mycobacterium tuberculosis Lipoprotein-derived Peptides and Target Cells Inhibits Mycobacterial Entry In Vitro.  

Science.gov (United States)

Tuberculosis (TB) continues being one of the diseases having the greatest mortality rates around the world, 8.7 million cases having been reported in 2011. An efficient vaccine against TB having a great impact on public health is an urgent need. Usually, selecting antigens for vaccines has been based on proteins having immunogenic properties for patients suffering TB and having had promising results in mice and non-human primates. Our approach has been based on a functional approach involving the pathogen-host interaction in the search for antigens to be included in designing an efficient, minimal, subunit-based anti-TB vaccine. This means that Mycobacterium tuberculosis has mainly been involved in studies and that lipoproteins represent an important kind of protein on the cell envelope which can also contribute towards this pathogen's virulence. This study has assessed the expression of four lipoproteins from M. tuberculosis H37Rv, that is, Rv1411c (LprG), Rv1911c (LppC), Rv2270 (LppN) and Rv3763 (LpqH), and the possible biological activity of peptides derived from these. Five peptides were found for these proteins which had high specific binding to both alveolar A549 epithelial cells and U937 monocyte-derived macrophages which were able to significantly inhibit mycobacterial entry to these cells in vitro. PMID:25041568

Ocampo, Marisol; Curtidor, Hernando; Vanegas, Magnolia; Patarroyo, Manuel A; Patarroyo, Manuel E

2014-12-01

217

Evaluation of the humoral response against mycobacterial peptides, homologous to MOG35-55, in multiple sclerosis patients.  

Science.gov (United States)

Bacillus Calmette-Guérin (BCG) and Mycobacterium avium subspecies paratuberculosis (MAP) have been associated with multiple sclerosis (MS). Clinical data indicates that BCG vaccination exerts anti-inflammatory effects in MS; conversely, MAP is thought to be one of the possible infectious factors responsible of MS through a molecular mimicry mechanism. A peptide-based indirect ELISA was used to detect antibodies against the encephalitogenic myelin oligodendrocyte glycoprotein (MOG)35-55 epitope, and two mycobacterial peptides sharing sequence homology with the latter: MAP_2619c352-361/BCG_1224355-364 and BCG_3329c64-74. Among 40 MS patients and 39 healthy volunteers included in the study, only MOG35-55 was capable of inducing a significantly higher humoral response in MS subjects compared to controls. Indeed, 11 out of 40 MS subjects (27.5%) and only 2 out of 39 controls (5%) were antibody-positive for MOG35-55 (p=0.01, AUC=0.65). These findings strengthen the importance of MOG35-55 in MS pathogenesis. The MAP and BCG MOG-homologues epitopes investigated were not recognized in MS patients. Overall, the results allow us concluding that sharing homology of linear epitopes is necessary but not sufficient to induce antibody-mediated cross-reactivity. PMID:25271190

Cossu, Davide; Mameli, Giuseppe; Masala, Speranza; Cocco, Eleonora; Frau, Jessica; Marrosu, Maria Giovanna; Sechi, Leonardo Antonio

2014-12-15

218

The chest radiographic appearances of non-tuberculous mycobacterial pulmonary infection in patients with acquired immunodeficiency syndrome  

International Nuclear Information System (INIS)

Objective: To study the chest radiographic appearances of the non-tuberculous mycobacterial (NTM) pulmonary infection in patients with acquired immune deficiency syndrome (AIDS). Methods: Ten patients with AIDS and NTM underwent chest X-ray radiography and 7 patients performed high-resolution CT (HRCT) scan. Chest radiographic features of' NTM in patients with AIDS were retrospectively analyzed. Results: The chest radiograph showed bilateral pulmonary involvement in 6 cases and single lung involvement in 4 cases (3 cases in the right, 1 case in the left). Patchy air space consolidation (6 cases), large consolidation (5 cases), cavitation (5 cases), small nodules (3 cases), military nodules (2 cases), linear opacity (1 cases) were demonstrated on radiography. On HRCT, air space consolidation (7 cases), small nodules (6 cases), large consolidation (5 cases) with cavitation and cylindric bronchiectasis after the absorption of consolidation, enlarged hilar and mediastinal lymph nodes (4 cases), ground-glass opacities (3 cases), military nodules and 'tree-in-bud' sign (2 case), pleural effusion (1 case), pericardial effusion (1 case) and fibrotic band (1 case) were found. Conclusion: The most common radiographic appearances of NTM in patients with AIDS are bilateral small nodules, large consolidation with cavitation and cylindric bronchiectasis, enlarged hilar and mediastinal lymph nodes. (authors)

219

Mycobacteria inhibition of IFN-gamma induced HLA-DR gene expression by up-regulating histone deacetylation at the promoter region in human THP-1 monocytic cells.  

Science.gov (United States)

Infection of macrophages with mycobacteria has been shown to inhibit the macrophage response to IFN-gamma. In the current study, we examined the effect of Mycobacteria avium, Mycobacteria tuberculosis, and TLR2 stimulation on IFN-gamma-induced gene expression in human PMA-differentiated THP-1 monocytic cells. Mycobacterial infection inhibited IFN-gamma-induced expression of HLA-DRalpha and HLA-DRbeta mRNA and partially inhibited CIITA expression but did not affect expression of IFN regulatory factor-1 mRNA. To determine whether inhibition of histone deacetylase (HDAC) activity could rescue HLA-DR gene expression, butyric acid and MS-275, inhibitors of HDAC activity, were added at the time of M. avium or M. tuberculosis infection or TLR2 stimulation. HDAC inhibition restored the ability of these cells to express HLA-DRalpha and HLA-DRbeta mRNA in response to IFN-gamma. Histone acetylation induced by IFN-gamma at the HLA-DRalpha promoter was repressed upon mycobacteria infection or TLR2 stimulation. HDAC gene expression was not affected by mycobacterial infection. However, mycobacterial infection or TLR2 stimulation up-regulated expression of mammalian Sin3A, a corepressor that is required for MHC class II repression by HDAC. Furthermore, we show that the mammalian Sin3A corepressor is associated with the HLA-DRalpha promoter in M. avium-infected THP-1 cells stimulated with IFN-gamma. Thus, mycobacterial infection of human THP-1 cells specifically inhibits HLA-DR gene expression by a novel pathway that involves HDAC complex formation at the HLA-DR promoter, resulting in histone deacetylation and gene silencing. PMID:15843570

Wang, Yue; Curry, Heather M; Zwilling, Bruce S; Lafuse, William P

2005-05-01

220

High Throughput Phenotypic Selection of Mycobacterium tuberculosis Mutants with Impaired Resistance to Reactive Oxygen Species Identifies Genes Important for Intracellular Growth  

Science.gov (United States)

Mycobacterium tuberculosis has the remarkable capacity to survive within the hostile environment of the macrophage, and to resist potent antibacterial molecules such as reactive oxygen species (ROS). Thus, understanding mycobacterial resistance mechanisms against ROS may contribute to the development of new anti-tuberculosis therapies. Here we identified genes involved in such mechanisms by screening a high-density transposon mutant library, and we show that several of them are involved in the intracellular lifestyle of the pathogen. Many of these genes were found to play a part in cell envelope functions, further strengthening the important role of the mycobacterial cell envelope in protection against aggressions such as the ones caused by ROS inside host cells. PMID:23320090

Dos Vultos, Tiago; Namouchi, Amine; Cimino, Mena; Pimentel, Madalena; Neyrolles, Olivier; Gicquel, Brigitte

2013-01-01

 
 
 
 
221

Interruption of the phosphoglucose isomerase gene results in glucose auxotrophy in Mycobacterium smegmatis.  

Science.gov (United States)

Two glycerol utilization mutants of Mycobacterium smegmatis that were unable to utilize most carbon sources except glucose were isolated. Supplementation of these media with small amounts of glucose restored growth in the mutants; these strains are therefore glucose auxotrophs. The mutant phenotype is complemented by the gene encoding phosphoglucose isomerase (pgi), and direct measurement of enzyme activities in the mutants suggests that this gene product is absent in the auxotrophic strains. Mapping of the mutant allele by Southern analysis demonstrates the presence of a 1-kb deletion extending into the coding sequence of pgi. The possible roles of phosphoglucose isomerase in mycobacterial cell wall synthesis and metabolic regulation are discussed. PMID:9098072

Tuckman, D; Donnelly, R J; Zhao, F X; Jacobs, W R; Connell, N D

1997-04-01

222

Does neutralization of gastric aspirates from children with suspected intrathoracic tuberculosis affect mycobacterial yields on MGIT culture?  

Science.gov (United States)

The microbiological confirmation of pulmonary tuberculosis in children relies on cultures of gastric aspirate (GA) specimens. Conventionally, GAs are neutralized to improve culture yields of mycobacteria. However, there are limited data to support this practice. To study the utility of neutralization of GAs with sodium bicarbonate in children with intrathoracic tuberculosis, a total of 116 children of either sex, aged 6 months to 14 years (median age, 120 months; interquartile range [IQR], 7 to 192 months), underwent gastric aspiration on 2 consecutive days. Gastric aspirates were divided into two aliquots, and only one aliquot was neutralized with 1% sodium bicarbonate. Both aliquots were processed for smear and culture examinations. Out of the 232 gastric aspirates, 12 (5.17%) were acid-fast bacilli (AFB) smear positive. There were no differences in smear positivity rates from samples with or without neutralization. The yield of Mycobacterium tuberculosis on a Bactec MGIT 960 culture system was significantly lower in the neutralized samples (16.3% [38/232]) than in the nonneutralized samples (21.5% [50/232]) (P = 0.023). There was no significant difference between the neutralized and the nonneutralized samples in time to detection using the MGIT 960 system (average, 24.6 days; IQR, 12 to 37 days) (P = 0.9). The contamination rates were significantly higher in the neutralized samples than in the nonneutralized samples (17.2% [40/232] versus 3.9% [9/232]) (P = 0.001). The agreement for positive mycobacterial culture between the two approaches was 66.5% (P = 0.001). Hence, we recommend that gastric aspirate samples not be neutralized with sodium bicarbonate prior to culture for M. tuberculosis. PMID:23536406

Parashar, Deepak; Kabra, Sushil K; Lodha, Rakesh; Singh, Varinder; Mukherjee, Aparna; Arya, Tina; Grewal, Harleen M S; Singh, Sarman

2013-06-01

223

Tomography high Resolution CT findings of nontuberculous mycobacterial pulmonary disease: Comparison between the first treatment and the re treatment group  

Energy Technology Data Exchange (ETDEWEB)

To analyze and compare the thin section CT findings of first and re treatment nontuberculous mycobacterial (NTM) pulmonary disease. Between January 2005 and April 2010, 121 patients with positive sputum culture for NTM were recruited. We included only 32 patients underwent high resolution chest CT and were confirmed by American Thoracic Society criteria NTM pulmonary infection (first treatment 15, re treatment 17 patients). CT images of 32 patients were reviewed retrospectively. We evaluated the frequency and laterality of the followings; nodule, increased density, bronchial change, parenchymal change. The significantly frequent CT findings of the re treatment NTM group were well defined nodules (retreatment 82.4%, first treatment 33.3%, p = 0.00), consolidations (retreatment 88.2%, first treatment 53.3%, p = 0.03), bronchial changes (bronchiectasis; retreatment 100%, first treatment 66.6%, p = 0.01, bronchial narrowing; retreatment 23.5%, first treatment 0%, p = 0.04 and mucoid impaction; retreatment-58.8%, first treatment-20.0%, p = 0.03) and atelectasis with bronchiectasis (retreatment-88.2%, first treatment 26.7%, p = 0.00). However, most of the evaluated thin section CT findings, such as centrilobular and ill defined nodules, lobular, segmental and subpleural consolidations, ground glass attenuation, bronchial wall thickening, cavities, pleural lesions, fibrotic band, emphysema and laterality of lesions, have not shown significant differences between first treatment and the re treatment group. Thin section CT findings of well defined nodules, consolidations, bronchial changes (bronchiectasis, bronchial narrowing and mucoid impaction) and atelectasis with bronchiectasis are highly suggestive of re treatment NTM pulmonary disease.

Gwak, Soon Hyuk; Cho, Bum Sang; Jeon, Min Hee; Kim, Eun Young; Kang, Min Ho; Yi, Kyung Sik; Lee, Seung Young; Kim, Sung Jin; Lee, Ki Man [Chungbuk National Univ., Cheongju, (Korea, Republic of)

2012-06-15

224

Molecular characterization of Mycobacterium tuberculosis H37Rv/Ra variants: distinguishing the mycobacterial laboratory strain.  

Science.gov (United States)

The Mycobacterium tuberculosis strains H37Rv and H37Ra are the most commonly used controls for M. tuberculosis identification in the clinical and research laboratory setting. To reduce the likelihood of misidentification and possible cross-contamination with this laboratory neotype, it is important to be able to distinguish H37 from clinical isolates. To provide a reference for identifying H37, we used multiple molecular techniques to characterize H37 strains, including 18 of the most frequently used variants available through the American Type Culture Collection. Isolates were genotyped using gene probes to IS6110 and IS1085. In addition, we performed polymorphic GC-rich sequence typing (PGRS), spoligotyping, determination of variable number of tandem repeats (VNTR), and PCR amplification of the mtp40, msx4, and mpp8 polymorphic regions. Southern hybridization with IS6110 provided the most discrimination, differentiating the 18 H37 isolates into 10 discrete patterns made up of 9 H37Rv variants and 1 H37Ra variant. PGRS, IS1085, mpp8, and spoligotyping were not able to distinguish any H37 variants, while VNTR and msx4 discriminated two. Only IS6110 and spoligotyping could distinguish the H37 strain from clinical isolates. In summary, spoligotyping and IS6110 provide a rapid and accurate way to identify H37 contamination, though IS6110 can, in addition, classify many of the H37 variants that would otherwise require phenotypic segregation. PMID:10970357

Bifani, P; Moghazeh, S; Shopsin, B; Driscoll, J; Ravikovitch, A; Kreiswirth, B N

2000-09-01

225

Mycobacterium bourgelatii sp. nov., a rapidly growing, non-chromogenic species isolated from the lymph nodes of cattle.  

Science.gov (United States)

Three independent strains of a rapidly growing, non-chromogenic member of the genus Mycobacterium were isolated from lymph nodes of French cattle. Identification of the isolates was carried out using a polyphasic approach. The nearly complete SSU rRNA gene sequences (>1200 bp) of the strains MLB-A23, MLB-A30 and MLB-A84(T) were identical. A phylogenetic analysis of these unique SSU rRNA gene sequences showed that these strains were most closely related to Mycobacterium intermedium. Further phylogenetic analysis based on concatenated sequences (2854 bp) of four housekeeping genes (hsp65, rpoB, sodA and tuf), the transfer-messenger RNA (tmRNA) and SSU rRNA genes indicated that these three strains represented a distinct species that shares a common ancestor with M. intermedium. Phylogenetic and phenotypic data strongly indicate that the strains MLB-A23, MLB-A30 and MLB-A84(T) belong to a novel mycobacterial species for which the name Mycobacterium bourgelatii sp. nov. is proposed. The type strain is MLB-A84(T) (?=?CIP 110557(T)?=?DSM 45746(T)). PMID:23990648

Guérin-Faublée, Véronique; Flandrois, Jean-Pierre; Pichat, Catherine; Boschiroli, Maria Laura; Lamy, Brigitte

2013-12-01

226

Molecular Identification and Conventional Susceptibility Testing of Iranian Clinical Mycobacterium fortuitum Isolates  

Directory of Open Access Journals (Sweden)

Full Text Available Rapidly growing mycobacteria (RGM are capable of producing diseases in humans. Since mycobacteria vary in their susceptibility, precise identification is critical for adoption of correct drug therapy. The main aim of this study was molecular identification and evaluation of antimicrobial susceptibility pattern of Iranian clinically isolated Myocbacterium fortuitum.Materials and MethodsA total of 72 presumptively identified isolates of clinical atypical mycobacteria collected by Isfahan Research Center for Infectious Diseases & Tropical Medicine during 2006-2008 were included in the current study. A combination of conventional and molecular tests was applied to identify the isolates. Molecular methods including genus and group specific PCR and PCR-Restriction Algorithm (PRA based on hsp65 gene were applied to achieve exact identification of mycobacterial strains. Antimicrobial susceptibility testing on M. fortuitum isolates was performed by in-house prepared broth microdilution test..ResultsOut of 72 collected atypical mycobacteria isolates, we identified 25 strains of M. fortuitum. All strains had the specific molecular markers of mycobacterial identity and similar species specific PRA pattern of the international type strain of M. fortuitum. Drug susceptibility testing showed that the M. fortuitum isolates are sensitive to amikacin, sulfamethoxazole and ciprofloxacin (100%, imipenem (92%, clarithromycin (76%, cefoxitin (56% and doxycycline (16%.ConclusionMolecular identification of atypical mycobacteria based on PRA is a reliable and rapid approach which can identify mycobacterial strains to the species level. Our study showed that M. fortuitum plays a significant role in pulmonary and extrapulmonary infection in patients and should be given proper considerations when clinical samples are processed.

Parvin Heidarieh

2010-01-01

227

Naive helper T cells from BCG-vaccinated volunteers produce IFN-gamma and IL-5 to mycobacterial antigen-pulsed dendritic cells.  

Science.gov (United States)

Mycobacterium bovis bacillus Calmette-Guérin (BCG) is a live vaccine that has been used in routine vaccination against tuberculosis for nearly 80 years. However, its efficacy is controversial. The failure of BCG vaccination may be at least partially explained by the induction of poor or inappropriate host responses. Dendritic cells (DCs) are likely to play a key role in the induction of immune response to mycobacteria by polarizing the reactivity of T lymphocytes toward a Th1 profile, contributing to the generation of protective cellular immunity against mycobacteria. In this study we aimed to investigate the production of Th1 and Th2 cytokines by naive CD4+ T cells to mycobacterial antigen-pulsed DCs in the group of young, healthy BCG vaccinated volunteers. The response of naive helper T cells was compared with the response of total blood lymphocytes. Our present results clearly showed that circulating naive CD45RA+CD4+ lymphocytes from BCG-vaccinated subjects can become effector helper cells producing IFN-gamma and IL-5 under the stimulation by autologous dendritic cells presenting mycobacterial protein antigen-PPD or infected with live M. bovis BCG bacilli. PMID:18519231

Kowalewicz-Kulbat, Magdalena; Ka?mierczak, Dominik; Donevski, Stefan; Biet, Franck; Pestel, Joël; Rudnicka, Wies?awa

2008-01-01

228

Drug-sensitive tuberculosis, multidrug-resistant tuberculosis, and nontuberculous mycobacterial pulmonary disease in nonAIDS adults: comparisons of thin-section CT findings  

International Nuclear Information System (INIS)

The aim of this work was to compare thin-section CT (TSCT) findings of drug-sensitive (DS) tuberculosis (TB), multidrug-resistant (MDR) TB, and nontuberculous mycobacterial (NTM) pulmonary disease in nonAIDS adults. During 2003, 216 (113 DS TB, 35 MDR TB, and 68 NTM) patients with smear-positive sputum for acid-fast bacilli (AFB), and who were subsequently confirmed to have mycobacterial pulmonary disease, underwent thoracic TSCT. The frequency of lung lesion patterns on TSCT and patients' demographic data were compared. The commonest TSCT findings were tree-in-bud opacities and nodules. On a per-person basis, significant differences were found in the frequency of multiple cavities and bronchiectasis (P<0.001, chi-square test and multiple logistic regression analysis). Multiple cavities were more frequent in MDR TB than in the other two groups and extensive bronchiectasis in NTM disease (multiple logistic regression analysis). Patients with MDR TB were younger than those with DS TB or NTM disease (P<0.001, multiple logistic regression analysis). Previous tuberculosis treatment history was significantly more frequent in patients with MDR TB or NTM disease (P<0.001, chi-square test and multiple logistic regression analysis). In patients with positive sputum AFB, multiple cavities, young age, and previous tuberculosis treatment history imply MDR TB, whereas extensive bronchiectasis, old age, and previous tuberculosis treatment history NTM disease. (orig.)story NTM disease. (orig.)

229

Naive helper T cells from BCG-vaccinated volunteers produce IFN-gamma and IL-5 to mycobacterial antigen-pulsed dendritic cells.  

Directory of Open Access Journals (Sweden)

Full Text Available Mycobacterium bovis bacillus Calmette-Gu?Šrin (BCG is a live vaccine that has been used in routine vaccination against tuberculosis for nearly 80 years. However, its efficacy is controversial. The failure of BCG vaccination may be at least partially explained by the induction of poor or inappropriate host responses. Dendritic cells (DCs are likely to play a key role in the induction of immune response to mycobacteria by polarizing the reactivity of T lymphocytes toward a Th1 profile, contributing to the generation of protective cellular immunity against mycobacteria. In this study we aimed to investigate the production of Th1 and Th2 cytokines by naive CD4+ T cells to mycobacterial antigen-pulsed DCs in the group of young, healthy BCG vaccinated volunteers. The response of naive helper T cells was compared with the response of total blood lymphocytes. Our present results clearly showed that circulating naive CD45RA+CD4+ lymphocytes from BCG-vaccinated subjects can become effector helper cells producing IFN-gamma and IL-5 under the stimulation by autologous dendritic cells presenting mycobacterial protein antigen-PPD or infected with live M. bovis BCG bacilli.

Jo??l Pestel

2008-06-01

230

Isolation of mycobacterial RNA.  

Science.gov (United States)

This chapter describes two protocols for isolating total RNA from mycobacteria: one for extraction from in vitro cultures and one for extraction from in vivo. In these protocols, RNA is liberated from mycobacteria by disruption with small glass beads in the presence of Trizol to stabilize the RNA. The RNA is further purified with DNAse treatment and RNeasy columns. This protocol leads to microgram quantities of RNA from log-phase cultures. PMID:20560069

Rustad, Tige R; Roberts, David M; Liao, Reiling P; Sherman, David R

2009-01-01

231

Fractionation of mycobacterial integral membrane proteins by continuous elution SDS-PAGE reveals the immunodominance of low molecular weight subunits for human T cells  

Science.gov (United States)

Integral membrane proteins (IMP) represent a serologically distinct class of mycobacterial antigens which are potent stimulators of human T cells (Mehrotra et al., Clin Exp Immunol 1995; 102:626). The range of IMP from Mycobacterium fortuitum was resolved by continuous elution SDS–PAGE to recover 31 discrete fractions covering bands up to ? 58 kD. The fractions, after removal of SDS, were subjected to human T cell proliferation assays for the identification of immunodominant molecule(s). A low molecular weight (<20kD) fraction was able to stimulate T cells from 11 out of 12 donors comprising mainly tuberculoid leprosy patients. The described protocol is well suited to situations where large quantities of antigenic protein mixtures must be processed in order to get the purified molecules/fractions in amounts required for immunoepidemiological studies. PMID:9328120

MEHROTRA, J; MITTAL, A; DHINDSA, M S; SINHA, S

1997-01-01

232

Rapid rebound of the Treg compartment in DEREG mice limits the impact of Treg depletion on mycobacterial burden, but prevents autoimmunity.  

Science.gov (United States)

The development of an effective vaccine against tuberculosis (Tb) represents one of the major medical challenges of this century. Mycobacterium bovis Bacille Calmette-Guerin (BCG), the only vaccine available at present, is mostly effective at preventing disseminated Tb in children, but shows variable protection against pulmonary Tb, the most common form in adults. The reasons for this poor efficacy are not completely understood, but there is evidence that T regulatory cells (Tregs) might be involved. Similarly, Tregs have been associated with the immunosuppression observed in patients infected with Tb and are therefore believed to play a role in pathogen persistence. Thus, Treg depletion has been postulated as a novel strategy to potentiate M. bovis BCG vaccination on one side, while on the other, employed as a therapeutic approach during chronic Tb infection. Yet since Tregs are critically involved in controlling autoimmune inflammation, elimination of Tregs may therefore also incur the danger of an excessive inflammatory immune response. Thus, understanding the dynamics and function of Tregs during mycobacterial infection is crucial to evaluate the potential of Treg depletion as a medical option. To address this, we depleted Tregs after infection with M. bovis BCG or Mycobacterium tuberculosis (Mtb) using DEREG mice, which express the diphtheria toxin (DT) receptor under the control of the FoxP3 locus, thereby allowing the selective depletion of FoxP3+ Tregs. Our results show that after depletion, the Treg niche is rapidly refilled by a population of DT-insensitive Tregs (diTregs) and bacterial load remains unchanged. On the contrary, impaired rebound of Tregs in DEREG × FoxP3GFP mice improves pathogen burden, but is accompanied by detrimental autoimmune inflammation. Therefore, our study provides the proof-of-principle that, although a high degree of Treg depletion may contribute to the control of mycobacterial infection, it carries the risk of autoimmunity. PMID:25050936

Berod, Luciana; Stüve, Philipp; Varela, Filipa; Behrends, Jochen; Swallow, Maxine; Kruse, Friederike; Krull, Freyja; Ghorbani, Peyman; Mayer, Christian T; Hölscher, Christoph; Sparwasser, Tim

2014-01-01

233

Synthesis, anti-mycobacterial, anti-trichomonas and anti-candida in vitro activities of 2-substituted-6,7-difluoro-3-methylquinoxaline 1,4-dioxides.  

Science.gov (United States)

A new series of 23 6,7-difluoro-3-methyl-2-phenylthio/phenylsulfonyl/phenylsulfinyl/benzylamino/phenylamino-quinoxaline 1,4-dioxides variously substituted in the phenyl moiety, was synthesized and submitted to in vitro evaluation for anti-mycobacterial, anti-trichomonas, anti-candida, anti-mycoplasma and antibacterial activities. In anti-mycobacterial assays, several compounds resulted active (MIC90 = 2.0-4.0 microg/ml) against Mycobacterium tuberculosis H37Rv. Anti-trichomonas screening showed a generally good activity of all compounds (MBC = 0.39-25.0 microg/ml) versus Trichomonas vaginalis, in particular the derivatives 5a,d, 7a, 9 and 11c ranged 0.39-0.78 microg/ml (metronidazole MBC = 12.5 microg/ml). Results of anti-candida assays showed that derivatives 7a, 8a,d and 9 were active against several species of Candida (C. albicans, C. krusei, C. parapsilosis and C. glabrata), having MIC50 between 3.9 and 31.25 microg/ml. The latter compounds were also submitted to anti-mycoplasma assay against Mycoplasma hominis, the results obtained showed that 7a, 8a,d and 9 inhibited the growth of the mycoplasma at the concentration of 0.1 mg/ml. In antibacterial tests only a few compounds showed an MIC50 lower than 62.5 microg/ml against representative strains of Gram-positive and Gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Vibrio alginolyticus and Pseudomonas aeruginosa). PMID:14987828

Carta, Antonio; Loriga, Mario; Paglietti, Giuseppe; Mattana, Antonella; Fiori, Pier Luigi; Mollicotti, Paola; Sechi, Leonardo; Zanetti, Stefania

2004-02-01

234

Rapid Rebound of the Treg Compartment in DEREG Mice Limits the Impact of Treg Depletion on Mycobacterial Burden, but Prevents Autoimmunity  

Science.gov (United States)

The development of an effective vaccine against tuberculosis (Tb) represents one of the major medical challenges of this century. Mycobacterium bovis Bacille Calmette-Guerin (BCG), the only vaccine available at present, is mostly effective at preventing disseminated Tb in children, but shows variable protection against pulmonary Tb, the most common form in adults. The reasons for this poor efficacy are not completely understood, but there is evidence that T regulatory cells (Tregs) might be involved. Similarly, Tregs have been associated with the immunosuppression observed in patients infected with Tb and are therefore believed to play a role in pathogen persistence. Thus, Treg depletion has been postulated as a novel strategy to potentiate M. bovis BCG vaccination on one side, while on the other, employed as a therapeutic approach during chronic Tb infection. Yet since Tregs are critically involved in controlling autoimmune inflammation, elimination of Tregs may therefore also incur the danger of an excessive inflammatory immune response. Thus, understanding the dynamics and function of Tregs during mycobacterial infection is crucial to evaluate the potential of Treg depletion as a medical option. To address this, we depleted Tregs after infection with M. bovis BCG or Mycobacterium tuberculosis (Mtb) using DEREG mice, which express the diphtheria toxin (DT) receptor under the control of the FoxP3 locus, thereby allowing the selective depletion of FoxP3+ Tregs. Our results show that after depletion, the Treg niche is rapidly refilled by a population of DT-insensitive Tregs (diTregs) and bacterial load remains unchanged. On the contrary, impaired rebound of Tregs in DEREG × FoxP3GFP mice improves pathogen burden, but is accompanied by detrimental autoimmune inflammation. Therefore, our study provides the proof-of-principle that, although a high degree of Treg depletion may contribute to the control of mycobacterial infection, it carries the risk of autoimmunity. PMID:25050936

Varela, Filipa; Behrends, Jochen; Swallow, Maxine; Kruse, Friederike; Krull, Freyja; Ghorbani, Peyman; Mayer, Christian T.

2014-01-01

235

Mycobacterium salmoniphilum infection in burbot Lota lota.  

Science.gov (United States)

Burbot Lota lota sampled from lakes Mjosa and Losna in southeastern Norway between 2005 and 2008 were found to be infected with Mycobacterium salmoniphilum at a culture-positive prevalence of 18.6 and 3.3%, respectively. The condition factor (CF) of mycobacteria-affected fish sampled from Mjøsa in 2008 was lower than the average CF of total sampled fish the same year. Externally visible pathological changes included skin ulceration, petechiae, exopthalmia and cataract. Internally, the infections were associated with capsulated, centrally necrotic granulomas, containing large numbers of acid-fast bacilli, found mainly in the mesenteries, spleen, heart and swim bladder. Mycobacterial isolates recovered on Middlebrook 7H10 agar were confirmed as M. salmoniphilum by phenotypical investigation and by partial sequencing of the 16S rRNA, rpoB and Hsp65genes as well as the internal transcribed spacer (ITS1) locus. This study adds burbot to the list of fish species susceptible to piscine mycobacteriosis and describes M. salmoniphilum infection in a non-salmonid fish for the first time. PMID:21797036

Zerihun, Mulualem Adam; Berg, Vidar; Lyche, Jan L; Colquhoun, Duncan J; Poppe, Trygve T

2011-05-24

236

Evaluation of INNO-LiPA mycobacteria v2 assay for identification of rapidly growing mycobacteria  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english A total of 54 rapidly growing mycobacteria (RGM) isolated from patients attended in the two hospitals of Cádiz Bay (Spain) were selected during a seven-year-period (2000-2006) in order to evaluate the INNO-LiPA Mycobacteria v2 assay for mycobacterial identification, based on the reverse hybridizatio [...] n principle. The strains were cultured in Löwenstein-Jensen and Middlebrook 7H9 media and identified to the species level by sequencing of the 16S rRNA, PCR-restriction enzyme analysis of the hsp65 gene, conventional tests and INNO-LiPA Mycobacteria v2 assay. By the molecular methods we identified a total of 12 different species: 23 Mycobacterium fortuitum, 11 M. chelonae, 10 M. abscessus, 2 M. senegalense, 1 M. alvei, 1 M. brumae, 1 M. mageritense, 1 M. mucogenicum, 1 M. neoaurum, 1 M. peregrinum, 1 M. septicum and 1 M. smegmatis. Fifty two strains (96.3%) were correctly identified by conventional techniques and 47 strains (87.0%) by INNO-LiPA Mycobacteria v2 assay. We find INNO-LiPA Mycobacteria v2 assay simple to perform but it provides few advantages in comparison with conventional methods and sometimes needs complementary tests to identify Mycobacterium fortuitum complex, M. chelonae complex and specific species due to the great heterogeneity in the RGM group.

Lidia, García-Agudo; Iría, Jesús; Manuel, Rodríguez-Iglesias; Pedro, García-Martos.

237

Evaluation of INNO-LiPA mycobacteria v2 assay for identification of rapidly growing mycobacteria  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english A total of 54 rapidly growing mycobacteria (RGM) isolated from patients attended in the two hospitals of Cádiz Bay (Spain) were selected during a seven-year-period (2000-2006) in order to evaluate the INNO-LiPA Mycobacteria v2 assay for mycobacterial identification, based on the reverse hybridizatio [...] n principle. The strains were cultured in Löwenstein-Jensen and Middlebrook 7H9 media and identified to the species level by sequencing of the 16S rRNA, PCR-restriction enzyme analysis of the hsp65 gene, conventional tests and INNO-LiPA Mycobacteria v2 assay. By the molecular methods we identified a total of 12 different species: 23 Mycobacterium fortuitum, 11 M. chelonae, 10 M. abscessus, 2 M. senegalense, 1 M. alvei, 1 M. brumae, 1 M. mageritense, 1 M. mucogenicum, 1 M. neoaurum, 1 M. peregrinum, 1 M. septicum and 1 M. smegmatis. Fifty two strains (96.3%) were correctly identified by conventional techniques and 47 strains (87.0%) by INNO-LiPA Mycobacteria v2 assay. We find INNO-LiPA Mycobacteria v2 assay simple to perform but it provides few advantages in comparison with conventional methods and sometimes needs complementary tests to identify Mycobacterium fortuitum complex, M. chelonae complex and specific species due to the great heterogeneity in the RGM group.

Lidia, García-Agudo; Iría, Jesús; Manuel, Rodríguez-Iglesias; Pedro, García-Martos.

1220-12-01

238

Mutation in alkylhydroperoxidase D gene dramatically decreases persistence of Mycobacterium bovis bacillus calmette-guerin in infected macrophage  

Directory of Open Access Journals (Sweden)

Full Text Available Background and Objectives: Mycobacterium tuberculosis is the leading cause of death from a single bacterial species in the world and is subjected to a highly oxidative environment in its host macrophage and consequently has evolved protective mechanisms against reactive oxygen and nitrogen intermediates. Alkyl hydroperoxidase D (AhpD is a molecule from these mycobacterial defense systems that has a dual function. It not only works with Alkyl hydroperoxidase C (AhpC in mycobacterial defense system against oxidative stress but also has a role in oxidation/reduction of succinyltransferase B (SucB, dihydrolipoamide dehydrogenase (LPD and AhpC. The present study was undertaken to find out the effects of inactivation of ahpD gene in the intra-macrophage persistence of resulted BCG mutant. Materials and Methods: We did allelic exchange mutagenesis in Mycobacterium bovis BCG and evaluate the effects of this mutagenesis in intracellular persistence of wild type BCG strains and ahpD mutant ones by comparing colony forming units (CFU in infected macrophage. Results: Our findings showed that after producing allelic exchange mutagenesis in ahpD gene of M.bovis BCG a sever decrease in the CFU?s of ahpD mutant BCG strains has been observed and intracellular persistence of ahpD mutant BCG strains decreased significantly. Conclusion: Mutagenesis in ahpD gene will cause significant decrease in intracellular survival of ahpD mutant strains than wild type M.bovis BCG strains and could leads to an inefficiency in pyruvate dehydrogenase pathway and could also impair impairs mycobacterial defense system against oxidative and nitrosative stress.

Farivar Taghi

2008-07-01

239

A role for tumour necrosis factor-?, complement C5 and interleukin-6 in the initiation and development of the mycobacterial cord factor trehalose 6,6?-dimycolate induced granulomatous response  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Trehalose 6,6?-dimycolate (TDM) is a glycolipid component of the mycobacterial cell wall that causes immune responses in mice similar to Mycobacterium tuberculosis (MTB) infection, including granuloma formation with production of proinflammatory cytokines. The precise roles of tumour necrosis factor (TNF)-?, complement C5 and interleukin (IL)-6 in the molecular events that lead to the initiation and maintenance of the granulomatous response to TDM have not been fully elucidated. Macrophage...

Welsh, Kerry J.; Abbott, April N.; Hwang, Shen-an; Indrigo, Jessica; Armitige, Lisa Y.; Blackburn, Michael R.; Hunter, Robert L.; Actor, Jeffrey K.

2008-01-01

240

Expression of the Mycobacterium bovis P36 gene in Mycobacterium smegmatis and the baculovirus/insect cell system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the present study we evaluated different systems for the expression of mycobacterial antigen P36 secreted by Mycobacterium bovis. P36 was detected by Western blot using a specific antiserum. The P36 gene was initially expressed in E. coli, under the control of the T7 promoter, but severe proteolysis prevented its purification. We then tried to express P36 in M. smegmatis and insect cells. For M. smegmatis, we used three different plasmid vectors differing in copy number and in the presence...

Bigi F.; Taboga O.; Romano M.I.; Alito A.; Fisanotti J.C.; Cataldi A.A.

1999-01-01

 
 
 
 
241

Capacity of murine T cells to retain long-term responsiveness to mycobacterial antigens is controlled by the H-2 complex.  

Science.gov (United States)

It is firmly established that the allelic composition of the H-2 complex has a prominent impact on the course of tuberculosis (TB) infection in mice, including granuloma formation, mycobacterial spread in the lungs, and the dynamics of mortality. Although intuitively obvious, the role of long-term specific T cell responses in the expression of corresponding phenotypes is poorly understood. In this study we have compared polyclonal lymph node cell response (cell yield, proliferation, surface markers, IL-4/interferon-gamma (IFN-gamma) production) to Mycobacterium tuberculosis H37Rv sonicate in repeated 10-day cycles of stimulation/rest between H-2 congenic IE-negative mouse strains, categorized on the basis of mortality following lethal challenge as TB-susceptible (C57B1/6), TB-resistant (4R) and BCG non-protected (B10.M). The capacity to retain specific responsiveness to repeated stimulation by mycobacterial antigens depended upon both the H-2 haplotype of the host and the immunizing dose of the antigen. 4R lymph node cells following either 50 microg/mouse or 100 microg/mouse immunization constantly responded to sonicate, increased in numbers, and after the third stimulation/rest cycle developed into a stable CD3+CD4+ cell line. B6 cells following either 50 microg/mouse or 100 microg/mouse immunization, and B10.M cells following 100 microg/mouse (but not 50 microg/mouse) immunization, lost the capacity to incorporate methyl-3H-thymidine during the second cycle, and died. Analogous results were obtained in the in vivo experiments, when the dynamics of the response over 12 weeks following a single immunization with the antigen was studied. In response to the antigen, cells from all three mouse strains produced significant amounts of IL-2 and IFN-gamma, but not IL-4, indicating that they belong predominantly to the Th1-like subset. Among noteworthy differences between the mouse strains was a clear deficiency of CD8+ T cells in B6 cultures, and an unusually high proportion of CD3+CD4-CD8- (double-negative) T cells in B10.M cultures following a high-dose immunization. PMID:9486398

Pichugin, A V; Khaidukov, S V; Moroz, A M; Apt, A S

1998-02-01

242

Increased frequency of {gamma}{delta} T cells in cerebrospinal fluid and peripheral blood of patients with multiple sclerosis: Reactivity, cytotoxicity, and T cell receptor V gene rearrangements  

Energy Technology Data Exchange (ETDEWEB)

Infiltrating {gamma}{delta} T cells are potentially involved in the central nervous system demyelination in multiple sclerosis (MS). To further study this hypothesis, we analyzed the frequency and functional properties of {gamma}{delta} T cells in peripheral blood (PB) and paired cerebrospinal fluid (CSF) of patients with MS and control subjects, including patients with other neurologic diseases (OND) and healthy individuals. The frequency analysis was performed under limiting dilution condition using rIL-2 and PHA. After PHA stimulation, a significantly increased frequency of {gamma}{delta} T cells was observed in PB and in CSF of MS patients as compared with PB and CSF of patients with OND. The frequency was represented equally in OND patients and normal individuals. Similarly, the IL-2-responsive {gamma}{delta} T cells occurred at a higher frequency in PB of MS than of control subjects. Forty-three percent of the {gamma}{delta} T cell clones isolates from PB and CSF of MS patients responded to heat shock protein (HSP70) but not HSP65, whereas only 2 of 30 control {gamma}{delta} T cell clones reacted to the HSP. The majority of the {gamma}{delta} T cell clones were able to induce non-MHC-restricted cytolysis of Daudi cells. All clones displayed a substantial reactivity to bacterial superantigens staphylococcal enterotoxin B and toxic shock syndrome toxin-1, irrespective of their {gamma}{delta} V gene usage. Furthermore, the {gamma}{delta} T cell clones expressed predominantly TCRDV2 and GV2 genes, whereas the clones derived from CSF of MS patients expressed either DV1 or DV2 genes. The obtained {gamma}{delta} clones, in general, represented rather heterogeneous clonal origins, even though a predominant clonal origin was found in a set of 10 {gamma}{delta} clones derived from one patient with MS. The present study provides new evidence supporting a possible role of {gamma}{delta} T cells in the secondary inflammatory processes in MS. 39 refs., 5 figs., 4 tabs.

Stinissen, P.; Vandevyver, C.; Medaer, R. [Dr. L. Willems Institute, Diepenbeek (Belgium)] [and others

1995-05-01

243

Serologic follow-up of IgG responses against recombinant mycobacterial proteins ML0405, ML2331 and LID-1 in a leprosy hyperendemic area in Venezuela  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Leprosy is a slowly evolving disease that occurs mainly in adults. In this study, the Mamaría Village, state of Portuguesa was selected because it had one of the highest prevalence rates (13.25%) of leprosy cases in 1997. Between 1998-2004, 20.2% of the 89 cases registered in this village were less [...] than 15 years old and 61.8% were males. Pau-cibacillary (PB) lesions were the predominant clinical forms identified, although also multibacillary (MB) forms were found. Additionally, 76% of the patients were bacteriologically negative. At the time of diagnosis, 75% of the patients presented with grade 0 disabilities, 23% with grade 1 and 2% with grade 2. Serum samples were collected from 18 PB and 15 MB patients, in addition to 14 family contacts, at the beginning and end of treatment. All the groups were re-evaluated during a three-year period (2008-2011). The proteins used for evaluation were ML0405, ML2331 and LID-1. These mycobacterial proteins were highly specific for Mycobacterium leprae and the IgG responses decreased in both MB and PB patients during multidrug treatment. Our results suggest that these antigens could be used as markers for successful treatment of non-reactional lepromatous patients.

Elsa, Rada; Malcolm S, Duthie; Steven G, Reed; Nacarid, Aranzazu; Jacinto, Convit.

244

Molecular typing of Mycobacterium tuberculosis isolates from a rural area of Kanpur by spoligotyping and mycobacterial interspersed repetitive units (MIRUs) typing.  

Science.gov (United States)

Molecular typing of Mycobacterium tuberculosis isolates has greatly facilitated the understanding of epidemiology of tuberculosis (TB). This study was done to characterize prevalent genotypes of M. tuberculosis on a collection of 97 isolates based on spoligotyping and mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) typing in rural area of Kanpur, North India. In this area different types of interventions are being undertaken and follow-up studies are progressing. Predominant spoligotypes prevalent in this region belonged to Central Asian-Delhi family (CAS1_Del) (37%), East African-Indian family (11%), T1 family (8%) and Beijing (4%) family. Highly distinct MIRU-VNTR genotypes were obtained. Significant spoligotypes such as Beijing and CAS1_Del type were further divided into subtypes with MIRU-VNTR. This preliminary study reveals that CAS is the most predominant family in this rural area of Kanpur. If confirmed in other areas, this combined approach of molecular typing can be preferably be used as first line tool for studying linkage and transmission dynamics of TB in India. PMID:18567544

Sharma, Pragya; Chauhan, Devendra Singh; Upadhyay, Prashant; Faujdar, Jaya; Lavania, Mallika; Sachan, Shailender; Katoch, Kiran; Katoch, Vishwa Mohan

2008-09-01

245

Thin-section CT findings of nontuberculous mycobacterial pulmonary diseases: comparison between Mycobacterium avium-intracellulare complex and Mycobacterium abscessus infection.  

Science.gov (United States)

We aimed to compare the CT findings of nontuberculous mycobacterial pulmonary diseases caused by Mycobacterium avium-intracellulare complex (MAC) and Mycobacterium abscessus. Two chest radiologists analyzed retrospectively the thin-section CT findings of 51 patients with MAC and 36 with M. abscessus infection in terms of patterns and forms of lung lesions. No significant difference was found between MAC and M. abscessus infection in the presence of small nodules, tree-in-bud pattern, and bronchiectasis. However, lobar volume decrease (p=0.001), nodule (p=0.018), airspace consolidation (p=0.047) and thin-walled cavity (p=0.009) were more frequently observed in MAC infection. The upper lobe cavitary form was more frequent in the MAC (19 of 51 patients, 37%) group than M. abscessus (5 of 36, 14%) (p=0.029), whereas the nodular bronchiectatic form was more frequent in the M. abscessus group ([29 of 36, 81%] vs. [27 of 51, 53%] in MAC) (p=0.012). In conclusion, there is considerable overlap in common CT findings of MAC and M. abscessus pulmonary infection; however, lobar volume loss, nodule, airspace consolidation, and thin-walled cavity are more frequently seen in MAC than M. abscessus infection. PMID:16224151

Chung, Myung Jin; Lee, Kyung Soo; Koh, Won-Jung; Lee, Ju Hyun; Kim, Tae Sung; Kwon, O Jung; Kim, Seonwoo

2005-10-01

246

Phenolic-glycolipid-1 and lipoarabinomannan preferentially modulate TCR- and CD28-triggered proximal biochemical events, leading to T-cell unresponsiveness in mycobacterial diseases  

Directory of Open Access Journals (Sweden)

Full Text Available Background Advanced stages of leprosy show T cell unresponsiveness and lipids of mycobacterial origin are speculated to modulate immune responses in these patients. Present study elucidates the role of phenolicglycolipid (PGL-1 and Mannose-capped lipoarabinomannan (Man-LAM on TCR- and TCR/CD28- mediated signalling. Results We observed that lipid antigens significantly inhibit proximal early signalling events like Zap-70 phosphorylation and calcium mobilization. Interestingly, these antigens preferentially curtailed TCR-triggered early downstream signalling events like p38 phosphorylation whereas potentiated that of Erk1/2. Further, at later stages inhibition of NFAT binding, IL-2 message, CD25 expression and T-cell blastogenesis by PGL-1 and Man-LAM was noted. Conclusion Altogether, we report that Man-LAM and PGL-1 preferentially interfere with TCR/CD28-triggered upstream cell signalling events, leading to reduced IL-2 secretion and T-cell blastogenesis which potentially could lead to immunosupression and thus, disease exacerbation, as noted in disease spectrum.

Dagur Pradeep

2012-09-01

247

Reactividad serológica y celular frente a proteínas micobacterianas en la enfermedad de Hansen / Serological and cellular reactivity to mycobacterial proteins in Hansen´s disease  

Scientific Electronic Library Online (English)

Full Text Available SciELO Venezuela | Language: Spanish Abstract in spanish Se diseñó un estudio para evaluar la reactividad inmunológica frente a diferentes preparaciones proteicas micobacterianas utilizando pruebas serológicas y de inmunidad celular. Para el estudio fueron incluídos pacientes con manifestaciones clínicas de lepra predominantemente de la forma multibacilar [...] . Todos los pacientes fueron adultos con edad comprendida entre 20 y 39 años. El 58% correspondía a la forma clínica de Lepra Lepromatosa (LL) n= 81, el 29% a la forma Borderline Lepromatosa (BL) n=41 y 10% a Borderline Borderline (BB) n=14. Solo el 3% fueron pacientes Borderline Tuberculoide (BT): 74% masculino y 26% femenino. El fenómeno reaccional más frecuente fue del tipo eritema nodoso leproso (ENL). Las proteínas micobacterianas ensayadas fueron: antígenos proteicos crudos totales de Mycobacterium leprae (MlSA), Mycobacterium bovis (MbSA y MbSA de excreción), antígeno proteico de excreción parcialmente purificado con una movilidad relativa de 30 kDa (Ml 30) y proteínas recombinantes de Mycobacterium (Mt70, Mb 65, Ml 36, 28, 18 y 10 kDa) encontrandose que las proteínas recombinantes (Ml10 kDa, Ml 36 kDa) a mayor carga bacilar presentaban una mayor reactividad serológica estadísticamente significativa (p= 0,0051 y 0,050 respectivamente). La proteína de 30 kDa fue predominantemente reconocida por anticuerpos de los pacientes multibacilares. Los resultados demuestran que el promedio de los valores de anticuerpos en pacientes no reaccionales fueron superiores en presencia de proteínas completas (MbSA y MbSA de exc) en comparación con el grupo de pacientes que presentaron fenómenos reaccionales (p=0,000567 y 0,000061 respectivamente) Este mismo comportamiento se observó frente a las proteínas micobacterianas individuales (30 kDa, 10 kDa y 36 kDa). La respuesta proliferativa de los linfocitos T en los pacientes multibacilares reaccionales y no reaccionales frente a las proteínas micobacterianas (MlSA, Ml 10 kDa, MbSA, MbSA de excreción) fue negativa en ambos grupos. Abstract in english The study was designed for evaluating immunological reactivity to various mycobacterial protein preparations using serological and cell-mediated immunological tests in patients with clinical leprosy signs, predominantly, with the multibacillary forms. All patients were adults with ages between 20 an [...] d 30 years. Fifty eight (n= 81) percent corresponded to Lepromatous Leprosy (LL), 29% (n= 41) to Borderline Lepromatous Leprosy (BL) and 10% (n=41) to Borderline Borderline Leprosy (BB); only 3% were Borderline Tuberculoid (BT) patients: 74% males and 26% females. The most frequent reactional phenomenon was of the Erythema Nodosum (ENL) type. The mycobacterial proteins tested were: total crude Mycobacterium leprae antigens (MISA); Mycobacterium bovis (MbSA and excretion MbSA); partially purified excretion protein antigen, with a 30kDa relative movility (Ml30); and recombinant M. leprae proteins (Mt70, Mb 65, Ml 36, 28, 18 and 10 kDa). Two of the recombinant proteins (Ml10 and Ml 36 kDa) presented a statiscally significant higher serological reactivity, directly related with a larger bacillary load (p= 0.0051 and 0.050 respectively). The 30 kDa protein was predominantly recognized by antibodies from multibacillary patients. Results show that mean antibody values were higher in non reactional patients when tested against complete proteins (MbSA and ex MbSA) when compared with the group of patients who presented reactional phenomena (p= 0.000567 and 0.000061, respectively). Comparing reactional with non reactional patients, it was seen that mean antibody values against complete proteins (MbSA and ex MbSA) were higher in non reactional individuals (p= 0.000567 and 0.000061, respectively). This same behavior occurred towards individual mycobacterial proteins (30, 10 and 36 kDa). The T lymphocyte prolypherative response in reactional and non reactional patients towards mycobacterial proteins (MlSA, Ml 10 kDa, MbSA, ex MbSA) was negative.

Elsa, Rada; Nacarid, Aranzazu; Vestalia, Rodríguez; Rafael, Borges; Jacinto, Convit.

248

[Value of the immunochromatographic assay for detecting IgG antibodies against 38 kDa mycobacterial antigen in diagnosis of tuberculosis].  

Science.gov (United States)

Despite of a fast development in the techniques of rapid identification of mycobacteria by molecular genetic techniques, serodiagnosis may be of special values as non-expensive, easy to perform method. Several serodiagnostic tests, principally those using immunoenzymatic (ELISA) methodology are available. The goal of our study was to evaluate one step coloured immunochromatographic assay detecting IgG antibodies against antigen 38 kDa (Rapid Test TB). Our material consisted of 278 serum samples--tuberculosis (n = 155), healthy (n = 36), sarcoidosis (n = 50), lung cancer (n = 25) mycobacterial infections other than tuberculosis (n = 12). Tuberculosis group consisted of new culture positive cases (n = 66), new culture negative cases (n = 23), chronic cases (n = 43) and extrapulmonary TB (n = 23). Specificity of 96% and sensitivity of 54% was obtained. In pulmonary TB sensitivity of 50% and in extrapulmonary TB of 74% was obtained. In chronic cases sensitivity of 70% and in new cases of 40% was received. Sensitivity of 44% in new culture positive cases and 30% in new culture negative cases was obtained. We conclude that immunochromatographic test may be a very useful tool improving tuberculosis diagnosis, especially in extrapulmonary tuberculosis. Strip test may be an interesting alternative as it is an extremely simple, rapid, and cheap technique. PMID:11200750

Demkow, U; Zielonka, T M; Filewska, M; Bia?as-Chromiec, B; Micha?owska-Mitczuk, D; Za?eska, J; Radziukiewicz-Byszewska, D; Strza?kowski, J; Augustynowicz-Kope?, E; Ku?, J; Zwolska, Z; Rowi?ska-Zakrzewska, E; Skopi?ska-Rózewska, E

2000-01-01

249

The use of variable-number tandem-repeat mycobacterial interspersed repetitive unit typing to identify laboratory cross-contamination with Mycobacterium tuberculosis.  

Science.gov (United States)

A retrospective study including 515 Mycobacterium tuberculosis isolates from 215 patients was conducted to investigate possible laboratory contamination with M. tuberculosis over a 1-year period in a university hospital. All cultures underwent variable-number tandem-repeat (VNTR) typing. Cultures suspected of being contaminated in the VNTR analysis and possible sources of contamination underwent mycobacterial interspersed repetitive unit (MIRU) typing further. Overall, 8 (3.7%) cases of 215 patients were considered possible false-positives. Five (2.3%) cultures might be contaminated during initial batching processing, and 1 (0.5%) and 4 (1.9%) cultures of them were further classified as presumed and possible cases, respectively, of cross-contamination on clinical grounds. Three (1.4%) cultures might be contaminated by cultures that had been processed in species identification procedures in the same laminar-flow hood. The 2-step strategy using VNTR and MIRU analyses in combination in this study appears to be a valuable means for the study of false-positive cultures. PMID:15878438

Yan, Jing-Jou; Jou, Ruwen; Ko, Wen-Chien; Wu, Jiunn-Jong; Yang, Mei-Lin; Chen, Hung-Mo

2005-05-01

250

Mycobacterium arupense pulmonary infection: Antibiotic resistance and restriction fragment length polymorphism analysis  

Directory of Open Access Journals (Sweden)

Full Text Available Mycobacterium arupense is a novel mycobacterium species. It was first identified from clinical specimens in 2006 and since then there have been only two reports of its recovery from clinical samples. In the present case M. arupense was isolated from the sputum of a 62-year-old man with a malignant mass in his left kidney, who presented with a one-month history of recurrent fever, dyspnea and haemoptysis. M. arupense was identified with sequencing of hsp65 and 16S rRNA genes. In the present study, its biochemical profile along with its resistance status and hsp65 RFLP analysis is presented.

Neonakis I

2010-01-01

251

Mycobacterium thermoresistibile: Case report of a rarely isolated mycobacterium from Europe and review of literature  

Directory of Open Access Journals (Sweden)

Full Text Available Mycobacterium thermoresistibile is a non-tuberculous mycobacterium strongly associated with human infections. Since 1966, there have only been six reports of its isolation from clinical samples. We report on the first case from Europe and review all the previous cases. Identification was achieved with sequencing of the 16S rRNA and hsp65 genes. This study presents its phenotypic and biochemical profile, susceptibilities to selected antibiotics and hsp65 polymerase chain reaction-restriction fragment length polymorphism profile with BsteII and Hae III .

Neonakis I

2009-01-01

252

Identification and characterization of a mycobacterial NAD(+)-dependent alcohol dehydrogenase with superior reduction of diacetyl to (S)-acetoin.  

Science.gov (United States)

An enzyme capable of reducing acetoin in the presence of NADH was purified from Mycobacterium sp. B-009, a non-clinical bacterial strain of soil origin. The enzyme is a homotetramer and can be classified as a medium-chain alcohol dehydrogenase/reductase based on the molecular weight of the monomer. Identification of the structural gene revealed a limited distribution of homologous genes only among actinomycetes. In addition to its activity as a reductase specific for (S)-acetoin (EC 1.1.1.76), the enzyme showed both diacetyl reductase (EC 1.1.1.304) and NAD(+)-dependent alcohol dehydrogenase (EC 1.1.1.1) activities. (S)-Acetoin and diacetyl reductases belong to a group of short-chain alcohol dehydrogenase/reductases but do not have superior abilities to dehydrogenate monoalcohols. Thus, the purified enzyme can be readily distinguished from other enzymes. We used the dual functionality of the enzyme to effectively reduce diacetyl to (S)-acetoin, coupled with the oxidation of 1-butanol. PMID:25082080

Takeda, Minoru; Anamizu, Shiori; Motomatsu, Shigekazu; Chen, Xue; Thapa Chhetri, Rajan

2014-11-01

253

The Differential Gene Expression Pattern of Mycobacterium tuberculosis in Response to Capreomycin and PA-824 versus First-Line TB Drugs Reveals Stress- and PE/PPE-Related Drug Targets  

Directory of Open Access Journals (Sweden)

Full Text Available Tuberculosis is a leading infectious disease causing millions of deaths each year. How to eradicate mycobacterial persistence has become a central research focus for developing next-generation TB drugs. Yet, the knowledge in this area is fundamentally limited and only a few drugs, notably capreomycin and PA-824, have been shown to be active against non-replicating persistent TB bacilli. In this study, we performed a new bioinformatics analysis on microarray-based gene expression data obtained from the public domain to explore genes that were differentially induced by drugs between the group of capreomycin and PA-824 and the group of mainly the first-line TB drugs. Our study has identified 42 genes specifically induced by capreomycin and PA-824. Many of these genes are related to stress responses. In terms of the distribution of identified genes in a specific category relative to the whole genome, only the categories of PE/PPE and conserved hypotheticals have statistical significance. Six among the 42 genes identified in this study are on the list of the top 100 persistence targets selected by the TB Structural Genomics Consortium. Further biological elucidation of their roles in mycobacterial persistence is warranted.

Li M. Fu

2009-01-01

254

Functional Complementation of the Essential Gene fabG1 of Mycobacterium tuberculosis by Mycobacterium smegmatis fabG but Not Escherichia coli fabG?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mycolic acids are a key component of the mycobacterial cell wall, providing structure and forming a major permeability barrier. In Mycobacterium tuberculosis mycolic acids are synthesized by type I and type II fatty acid synthases. One of the enzymes of the type II system is encoded by fabG1. We demonstrate here that this gene can be deleted from the M. tuberculosis chromosome only when another functional copy is provided elsewhere, showing that under normal culture conditions fabG1 is essent...

Parish, Tanya; Roberts, Gretta; Laval, Francoise; Schaeffer, Merrill; Daffe?, Mamadou; Duncan, Ken

2007-01-01

255

Cytomegalovirus infection modulates the phenotype and functional profile of the T-cell immune response to mycobacterial antigens in older life?  

Science.gov (United States)

Infection with Cytomegalovirus is associated with accelerated immunosenescence. Expansions of CMV-specific T cell responses have previously been demonstrated to affect the ability of T cells to respond to other infections. Most people above 60 years of age display M. tuberculosis-specific immunity because of vaccination, exposure, or both. T-cell responses can be assessed by measuring intracellular IFN-? in vitro after tuberculin stimulation. Here we investigated tuberculin-specific CD4 T-cell responses in independently living healthy older people in the South of England using flow-cytometry. Individuals were investigated for tuberculin and CMV-specific T-cell immunity using in vitro antigen stimulation followed by intracellular staining for IFN-?, TNF-?, IL2, as well as degranulation and CD154 upregulation. We also examined a control group of younger individuals (20–35 years of age). There was no significant difference between older and young people in regards to tuberculin responsiveness of CD4 T-cells; however, older people seemed to show more outliers. Increased responsiveness to tuberculin was significantly correlated to CMV responsiveness but not age. In older donors, the memory phenotype of tuberculin-induced T-cells was significantly skewed towards a more terminal differentiation phenotype in CMV-infected compared to uninfected individuals and the degree of skewing correlated quantitatively with the size of the CMV-specific CD4 T-cell response. This is a fundamental advance over previous reports of changes of the tuberculin-specific CD4 T-cell response with CMV serostatus. Our results show that how the immune system responds to CMV has a fundamental impact on the phenotype and function of the immune response to mycobacterial antigens in older life. PMID:24370373

Terrazzini, Nadia; Bajwa, Martha; Vita, Serena; Thomas, David; Smith, Helen; Vescovini, Rosanna; Sansoni, Paolo; Kern, Florian

2014-01-01

256

The radiology of IRIS (immune reconstitution inflammatory syndrome) in patients with mycobacterial tuberculosis and HIV co-infection: appearances in 11 patients  

International Nuclear Information System (INIS)

Aim: To determine the radiological manifestations of IRIS (immune reconstitution inflammatory syndrome) in patients with HIV and mycobacterium tuberculosis co-infection, in the context of their demographic and clinical data. Materials and methods: The radiological imaging, demographic and clinical data of 11 patients diagnosed with IRIS associated with HIV and mycobacterial tuberculosis co-infection were studied retrospectively. Where available, follow-up imaging studies were also reviewed. Results: The most common radiological feature of IRIS was lymph node enlargement (73%), with central low attenuation centres, in keeping with necrosis, present in most of these cases (88%). Most commonly affected were intra-abdominal nodes (70%), followed by axillary (40%) and mediastinal lymph nodes (36%). Within the lung parenchyma, diffuse, bilateral pulmonary nodules were seen in 55% of cases. Unilateral small volume pleural effusions were seen in two cases with associated parenchymal changes seen in only one. Small volume ascites was seen in two cases. Thirty-six percent of cases presented with new or worsening abscesses despite treatment. In this context, image-guided radiological drainage proved a useful adjunct to the conventional medical therapy for IRIS. The most common clinical signs of IRIS included fever (64%), abdominal pain (36%) and cough (27%). Conclusion: We have described the radiological features that are characteristic in IRIS and the importance of putting thesin IRIS and the importance of putting these into context with the clinical and pathological findings as part of a multidisciplinary approach in making the diagnosis. The role of the radiologist is central in diagnosis, monitoring of disease progression and management of complications in patients with IRIS

257

Sternal Osteomyelitis Caused by Gordonia bronchialis after Open-Heart Surgery.  

Science.gov (United States)

We report the case of a deep sternal wound infection with sternal osteomyelitis caused by Gordonia bronchialis after open-heart surgery. The isolate was identified as a G. bronchialis by 16S rRNA and hsp65 gene sequencing, having initially been misidentified as a Rhodococcus by a commercial phenotypic identification system. PMID:25024874

Chang, Jeong-Hyun; Ji, Misuk; Hong, Hyo-Lim; Choi, Sang-Ho; Kim, Yang-Soo; Chung, Cheol-Hyun; Sung, Heungsup; Kim, Mi-Na

2014-06-01

258

Sternal Osteomyelitis Caused by Gordonia bronchialis after Open-Heart Surgery  

Science.gov (United States)

We report the case of a deep sternal wound infection with sternal osteomyelitis caused by Gordonia bronchialis after open-heart surgery. The isolate was identified as a G. bronchialis by 16S rRNA and hsp65 gene sequencing, having initially been misidentified as a Rhodococcus by a commercial phenotypic identification system. PMID:25024874

Chang, Jeong-Hyun; Ji, Misuk; Hong, Hyo-Lim; Choi, Sang-Ho; Kim, Yang-Soo; Chung, Cheol-Hyun; Kim, Mi-Na

2014-01-01

259

Induction of human hsp60 expression in monocytic cell lines.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Both bacterial and mammalian heat shock proteins (HSP) are recognized by some T cells, and hsp60 recognition has been implicated in rheumatoid arthritis. We have developed a model to study the induction of hsp60 in human monocytic cell lines. An anti-mycobacterial hsp65 mAb (ML30), cross-reacting with human hsp60 was used to screen 21 human tumor cell lines in Western blot analysis. All T cell and B cell lymphomas constitutively expressed hsp60 protein at moderate to high levels, while little...

Ferm, Mt; So?derstro?m, K.; Jindal, S.; Gro?nberg, A.; Ivanyi, J.; Young, R.; Kiessling, R.

1992-01-01

260

A randomised controlled trial of the effects of albendazole in pregnancy on maternal responses to mycobacterial antigens and infant responses to bacille Calmette-Guérin (BCG immunisation [ISRCTN32849447  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Maternal schistosomiasis and filariasis have been shown to influence infant responses to neonatal bacille Calmette-Guérin (BCG immunisation but the effects of maternal hookworm, and of de-worming in pregnancy, are unknown. Methods In Entebbe, Uganda, we conducted a randomised, double-blind, placebo-controlled trial of a single dose of 400 mg of albendazole in the second trimester of pregnancy. Neonates received BCG. Interferon-gamma (IFN-? and interleukin (IL-5 responses to a mycobacterial antigen (crude culture filtrate proteins (CFP of Mycobacterium tuberculosis were measured in a whole blood assay. We analysed results for binary variables using ?2 tests and logistic regression. We analysed continuous variables using Wilcoxon's tests. Results Maternal hookworm was associated with reduced maternal IFN-? responses to CFP (adjusted odds ratio for IFN-? > median response: 0.14 (95% confidence interval 0.02–0.83, p = 0.021. Conversely, maternal hookworm was associated with subsequent increased IFN-? responses in their one-year-old infants (adjusted OR 17.65 (1.20–258.66; p = 0.013. Maternal albendazole tended to reduce these effects. Conclusion Untreated hookworm infection in pregnancy was associated with reduced maternal IFN-? responses to mycobacterial antigens, but increased responses in their infants one year after BCG immunisation. The mechanisms of these effects, and their implications for protective immunity remain, to be determined.

Nampijja Margaret

2005-12-01

 
 
 
 
261

Prospective Universal Application of Mycobacterial Interspersed Repetitive-Unit-Variable-Number Tandem-Repeat Genotyping To Characterize Mycobacterium tuberculosis Isolates for Fast Identification of Clustered and Orphan Cases?  

Science.gov (United States)

The use of molecular tools for genotyping Mycobacterium tuberculosis isolates in epidemiological surveys in order to identify clustered and orphan strains requires faster response times than those offered by the reference method, IS6110 restriction fragment length polymorphism (RFLP) genotyping. A method based on PCR, the mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) genotyping technique, is an option for fast fingerprinting of M. tuberculosis, although precise evaluations of correlation between MIRU-VNTR and RFLP findings in population-based studies in different contexts are required before the methods are switched. In this study, we evaluated MIRU-VNTR genotyping (with a set of 15 loci [MIRU-15]) in parallel to RFLP genotyping in a 39-month universal population-based study in a challenging setting with a high proportion of immigrants. For 81.9% (281/343) of the M. tuberculosis isolates, both RFLP and MIRU-VNTR types were obtained. The percentages of clustered cases were 39.9% (112/281) and 43.1% (121/281) for RFLP and MIRU-15 analyses, and the numbers of clusters identified were 42 and 45, respectively. For 85.4% of the cases, the RFLP and MIRU-15 results were concordant, identifying the same cases as clustered and orphan (kappa, 0.7). However, for the remaining 14.6% of the cases, discrepancies were observed: 16 of the cases clustered by RFLP analysis were identified as orphan by MIRU-15 analysis, and 25 cases identified as orphan by RFLP analysis were clustered by MIRU-15 analysis. When discrepant cases showing subtle genotypic differences were tolerated, the discrepancies fell from 14.6% to 8.6%. Epidemiological links were found for 83.8% of the cases clustered by both RFLP and MIRU-15 analyses, whereas for the cases clustered by RFLP or MIRU-VNTR analysis alone, links were identified for only 30.8% or 38.9% of the cases, respectively. The latter group of cases mainly comprised isolates that could also have been clustered, if subtle genotypic differences had been tolerated. MIRU-15 genotyping seems to be a good alternative to RFLP genotyping for real-time interventional schemes. The correlation between MIRU-15 and IS6110 RFLP findings was reasonable, although some uncertainties as to the assignation of clusters by MIRU-15 analysis were identified. PMID:19458183

Alonso-Rodriguez, Noelia; Martinez-Lirola, Miguel; Sanchez, M. Luisa; Herranz, Marta; Penafiel, Teresa; Bonillo, Magdalena del Carmen; Gonzalez-Rivera, Milagros; Martinez, Juan; Cabezas, Teresa; Diez-Garcia, Luis Felipe; Bouza, Emilio; Garcia de Viedma, Dario

2009-01-01

262

Expression of the Mycobacterium bovis P36 gene in Mycobacterium smegmatis and the baculovirus/insect cell system  

Directory of Open Access Journals (Sweden)

Full Text Available In the present study we evaluated different systems for the expression of mycobacterial antigen P36 secreted by Mycobacterium bovis. P36 was detected by Western blot using a specific antiserum. The P36 gene was initially expressed in E. coli, under the control of the T7 promoter, but severe proteolysis prevented its purification. We then tried to express P36 in M. smegmatis and insect cells. For M. smegmatis, we used three different plasmid vectors differing in copy number and in the presence of a promoter for expression of heterologous proteins. P36 was detected in the cell extract and culture supernatant in both expression systems and was recognized by sera from M. bovis-infected cattle. To compare the expression level and compartmentalization, the MPB70 antigen was also expressed. The highest production was reached in insect cell supernatants. In conclusion, M. smegmatis and especially the baculovirus expression system are good choices for the production of proteins from pathogenic mycobacteria for the development of mycobacterial vaccines and diagnostic reagents.

Bigi F.

1999-01-01

263

Expression of the Mycobacterium bovis P36 gene in Mycobacterium smegmatis and the baculovirus/insect cell system  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english In the present study we evaluated different systems for the expression of mycobacterial antigen P36 secreted by Mycobacterium bovis. P36 was detected by Western blot using a specific antiserum. The P36 gene was initially expressed in E. coli, under the control of the T7 promoter, but severe proteoly [...] sis prevented its purification. We then tried to express P36 in M. smegmatis and insect cells. For M. smegmatis, we used three different plasmid vectors differing in copy number and in the presence of a promoter for expression of heterologous proteins. P36 was detected in the cell extract and culture supernatant in both expression systems and was recognized by sera from M. bovis-infected cattle. To compare the expression level and compartmentalization, the MPB70 antigen was also expressed. The highest production was reached in insect cell supernatants. In conclusion, M. smegmatis and especially the baculovirus expression system are good choices for the production of proteins from pathogenic mycobacteria for the development of mycobacterial vaccines and diagnostic reagents.

F., Bigi; O., Taboga; M.I., Romano; A., Alito; J.C., Fisanotti; A.A., Cataldi.

1999-01-01

264

Mycobacterial contamination of fibreoptic bronchoscopes.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Contamination of bronchoalveolar lavage specimens by environmental mycobacteria in hospital water supplies may lead to diagnostic confusion, particularly in immunocompromised patients. Mycobacteria may become concentrated in the tubing of bronchoscope disinfecting machines. It is very difficult to eradicate these organisms once contamination has occurred.

Brown, N. M.; Hellyar, E. A.; Harvey, J. E.; Reeves, D. S.

1993-01-01

265

Mycobacterial Aerosols and Respiratory Disease  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Environmental opportunistic mycobacteria, including Mycobacterium avium, M. terrae, and the new species M. immunogenum, have been implicated in outbreaks of hypersensitivity pneumonitis or respiratory problems in a wide variety of settings. One common feature of the outbreaks has been exposure to aerosols. Aerosols have been generated from metalworking fluid during machining and grinding operations as well as from indoor swimming pools, hot tubs, and water-damaged buildings. Environmental opp...

Falkinham, Joseph O.

2003-01-01

266

Infecciones micobacterianas en pacientes infectados por el virus de la inmunodeficiencia humana en Cali, Colombia / Mycobacterial infections in patients infected with human immunodeficiency virus in Cali, Colombia  

Scientific Electronic Library Online (English)

Full Text Available SciELO Public Health | Language: Spanish Abstract in spanish Se determinó la prevalencia de las infecciones por micobacterias en una muestra de 155 individuos infectados por el virus de la inmunodeficiencia humana (VIH) tratados en el Instituto de los Seguros Sociales (ISS) de Cali, Colombia. Se les realizó la prueba de la tuberculina (PPD 2UT RT23) y se inve [...] stigó activamente la presencia de micobacterias mediante microscopia directa y cultivo de sangre, orina, heces y aspirado gástrico; cuando así lo indicó el cuadro clínico, también se examinaron y cultivaron muestras de líquido cefalorraquídeo, médula ósea y esputo. La ausencia de reactividad a la tuberculina fue significativamente más frecuente en los pacientes que en los controles (91,3%, frente a 57,4%. ji² = 33; P = 0). La prevalencia de la tuberculosis fue de 6,5%, en comparación con 0,04% en los afiliados al ISS VIH-negativos (intervalo de confianza binomial exacto de 95%: 0,0313 a 0,1154%). Las micobacterias no tuberculosas (MNT), presentes en 43 pacientes, fueron significativamente más frecuentes que Mycobacterium tuberculosis (27,7% frente a 6,5%. ji² = 24,78; P = 0,000 001), pero solo fueron causa de enfermedad en algunos casos. Las especies más frecuentes fueron las del complejo M. avium-intracellulare. M. avium-intracellulare y M. fortuitum tuvieron una prevalencia total de 7,1% y fueron las MNT de mayor prevalencia como causantes de enfermedad en estos pacientes (4,5%); además fueron responsables de tres casos de infección diseminada. La enfermedad clínica por M. tuberculosis o MNT y la anergia completa a la tuberculina se asociaron al estadio IV de la infección por VIH y a los recuentos de linfocitos CD4 Abstract in english The prevalence of mycobacterial infections was determined in a sample of 155 individuals infected with human immunodeficiency virus (HIV) who were treated in the Social Security Institute (SSI) of Cali, Colombia. A tuberculin test (2 TU PPD RT23) was used, and the presence of mycobacteria was checke [...] d through direct microscopy and culturing blood, urine, feces, and gastric aspirate. When clinically indicated, samples of cerebrospinal fluid, bone marrow, and sputum were also examined and cultivated. The absence of reactivity to tuberculin was significantly more frequent in the patients than in the controls (91.3%, compared to 57.4%; chi² = 33, P = 0). The prevalence of tuberculosis was 6.5%, in comparison with 0.04% among a group of HIV-negative ISS members (exact binomial 95% confidence interval: 0.0313% to 0.1154%). Non- tuberculous mycobacteria (NTM), present in 43 patients, were significantly more frequent than Mycobacterium tuberculosis (27.7%, versus 6.5%; chi² = 24.78, P = 0.000 001), but they caused illness only in some cases. The most common species were those of the M. avium-intracellulare complex. M. avium-intracellulare and M. fortuitum had a total prevalence of 7.1% and were the most-prevalent NTM that caused disease in these patients (4.5%); they were also responsible for three cases of disseminated infection. Clinical disease caused by M. tuberculosis or NTM and complete tuberculin anergy were associated with stage-IV HIV infection and with CD4 lymphocyte counts

María del Pilar, Crespo; Raúl, Heli Corral; Alberto, Alzate; Gabriel, Carrasquilla; Nory, Sánchez.

1999-10-01

267

Gene transfer and gene therapy  

Energy Technology Data Exchange (ETDEWEB)

This book reports the progress in gene transfer that has been made in various species, from Drosophila to higher mammals, including illustrative examples of germline gene transfer and tissue-specific somatic gene regulation in the mouse. Important new information regarding developmental control of gene transcription includes the delineation of distal elements, both cis and trans, controlling specific gene regulation. The book also offers an overview of vectors for gene transfer, including retroviral vectors and new retroviral packaging cell lines designed to minimize production of replication-competent virus.

Beaudet, A.L.; Mulligan, R.; Verma, I.M.

1988-01-01

268

Genes | About  

... JLPEA JMSE JPM JRFM JSAN Land Laws Life Lubricants Machines Marine Drugs Materials Mathematics Medical Sciences Membranes Metabolites Metals Microarrays Micromachines Microorganisms Minerals ...access journal which provides an advanced forum for studies related to genes, genetics and genomics. It publishes reviews, research articles, communications ...as supplementary material Scope This journal covers all topics related to genes, genetics and genomics. Topics of interest include but are not limited ...to: DNA; RNA; chromosomes; reproduction; heredity; genealogy; interaction of multiple genes; genetic code; pseudogene; gene structure; gene expression; recombination and ...

269

É possível uma vacina gênica auxiliar no controle da tuberculose? / Could a DNA vaccine be useful in the control of tuberculosis?  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Vacinas de DNA, ainda em fase de experimentação e testes clínicos, podem se tornar uma importante ferramenta de combate a doenças infecciosas para as quais, até hoje, não existe prevenção segura e eficaz, como a tuberculose. Nos últimos anos vários estudos têm sido dedicados ao desenvolvimento de va [...] cinas de DNA que codificam proteínas de micobactérias, entre as quais destacam-se as que codificam o antígeno 85 (Ag 85) e a proteína de choque térmico de 65 kDa (hsp65). Estes dois antígenos foram os mais estudados apresentando resultados bastante satisfatórios em ensaios pré-clínicos e com grande volume de dados registrados na literatura. Além de proteger contra infecção experimental por Mycobacterium tuberculosis virulenta, a vacina DNA-hsp65 também apresenta atividade terapêutica, ou seja, é capaz de curar os animais previamente infectados, inclusive aqueles com bacilos resistentes a múltiplas drogas. Esta vacina, hoje em avaliação clínica no Brasil também para o tratamento de câncer, é capaz de induzir a produção de citocinas de padrão Th1 tal como IFN- interferon-gama, associadas ao controle da doença. Além disso, a vacina de DNA-hsp65 é capaz de estimular clones de células CD8 citotóxicos e CD4 que podem ser caracterizados como células de memória sendo responsáveis por conferir imunidade duradoura contra a infecção. Quando utilizada na terapia da infecção, a vacina de DNA-hsp65 faz com que haja uma mudança no padrão de resposta imune, induzindo a secreção de citocinas de padrão Th1 criando um ambiente favorável à erradicação do bacilo. Os resultados demonstram ainda que a via de administração e a formulação na qual a vacina é administrada exerce fundamental influência no padrão e duração da resposta imune desencadeada. O conjunto de resultados hoje disponíveis mostra que uma vacina de DNA contra a tuberculose contribuirá de maneira significativa no controle desta doença. Abstract in english The DNA vaccines currently under pre-clinical and clinical development may prove to be important tools in combating infectious diseases, such as tuberculosis, for which no safe and effective form of prevention has yet been developed. In recent years, several studies have aimed to develop a DNA vacci [...] ne encoding mycobacterial proteins such as antigen 85 (Ag85) and the 65-kDa mycobacterial heat shock protein (hsp65). The latter is protective against virulent infection with Mycobacterium tuberculosis (including multidrug-resistant strains). The hsp65 DNA vaccine, currently under clinical evaluation in Brazil for cancer therapy, is able to induce the secretion of Th1 cytokines, such as gamma-interferon, associated with disease control. Furthermore, this vaccine stimulates cytotoxic CD8 and CD4 T-cell clones that can be characterized as memory cells, which are responsible for effective and long-lasting immunity against tuberculosis. When used as a therapeutic agent in inoculated mice, the hsp65 DNA vaccine promotes changes in the immunity profile, triggering the secretion of Th1 cytokines and establishing a favorable environment for the elimination of bacilli. The results also demonstrate that the route of administration, as well as the formulation in which the vaccine is administered, fundamentally influence the pattern and duration of the immune response induced. Taking all currently available data into account, we can conclude that a DNA vaccine against tuberculosis could contribute significantly to the control of the disease.

José Maciel, Rodrigues Júnior; Karla de Melo, Lima; Arlete Aparecida Martins Coelho, Castelo; Vânia Luiza Deperon Bonato, Martins; Sandra Aparecida dos, Santos; Lucia Helena, Faccioli; Célio Lopes, Silva.

2004-08-01

270

Mycobacteria mobility shift assay: a method for the rapid identification of Mycobacterium tuberculosis and nontuberculous mycobacteria  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The identification of mycobacteria is essential because tuberculosis (TB) and mycobacteriosis are clinically indistinguishable and require different therapeutic regimens. The traditional phenotypic method is time consuming and may last up to 60 days. Indeed, rapid, affordable, specific and easy-to-p [...] erform identification methods are needed. We have previously described a polymerase chain reaction-based method called a mycobacteria mobility shift assay (MMSA) that was designed for Mycobacterium tuberculosis complex (MTC) and nontuberculous mycobacteria (NTM) species identification. The aim of this study was to assess the MMSA for the identification of MTC and NTM clinical isolates and to compare its performance with that of the PRA-hsp65 method. A total of 204 clinical isolates (102 NTM and 102 MTC) were identified by the MMSA and PRA-hsp65. For isolates for which these methods gave discordant results, definitive species identification was obtained by sequencing fragments of the 16S rRNA and hsp65 genes. Both methods correctly identified all MTC isolates. Among the NTM isolates, the MMSA alone assigned 94 (92.2%) to a complex or species, whereas the PRA-hsp65 method assigned 100% to a species. A 91.5% agreement was observed for the 94 NTM isolates identified by both methods. The MMSA provided correct identification for 96.8% of the NTM isolates compared with 94.7% for PRA-hsp65. The MMSA is a suitable auxiliary method for routine use for the rapid identification of mycobacteria.

Letícia Muraro, Wildner; Maria Luiza, Bazzo; Susie Coutinho, Liedke; Christiane Lourenço, Nogueira; Gabriela, Segat; Simone Gonçalves, Senna; Aline Daiane, Schlindwein; Jaquelline Germano de, Oliveira; Darcita B, Rovaris; Claudio A, Bonjardim; Erna G, Kroon; Paulo CP, Ferreira.

271

Mycobacteria mobility shift assay: a method for the rapid identification of Mycobacterium tuberculosis and nontuberculous mycobacteria  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The identification of mycobacteria is essential because tuberculosis (TB) and mycobacteriosis are clinically indistinguishable and require different therapeutic regimens. The traditional phenotypic method is time consuming and may last up to 60 days. Indeed, rapid, affordable, specific and easy-to-p [...] erform identification methods are needed. We have previously described a polymerase chain reaction-based method called a mycobacteria mobility shift assay (MMSA) that was designed for Mycobacterium tuberculosis complex (MTC) and nontuberculous mycobacteria (NTM) species identification. The aim of this study was to assess the MMSA for the identification of MTC and NTM clinical isolates and to compare its performance with that of the PRA-hsp65 method. A total of 204 clinical isolates (102 NTM and 102 MTC) were identified by the MMSA and PRA-hsp65. For isolates for which these methods gave discordant results, definitive species identification was obtained by sequencing fragments of the 16S rRNA and hsp65 genes. Both methods correctly identified all MTC isolates. Among the NTM isolates, the MMSA alone assigned 94 (92.2%) to a complex or species, whereas the PRA-hsp65 method assigned 100% to a species. A 91.5% agreement was observed for the 94 NTM isolates identified by both methods. The MMSA provided correct identification for 96.8% of the NTM isolates compared with 94.7% for PRA-hsp65. The MMSA is a suitable auxiliary method for routine use for the rapid identification of mycobacteria.

Letícia Muraro, Wildner; Maria Luiza, Bazzo; Susie Coutinho, Liedke; Christiane Lourenço, Nogueira; Gabriela, Segat; Simone Gonçalves, Senna; Aline Daiane, Schlindwein; Jaquelline Germano de, Oliveira; Darcita B, Rovaris; Claudio A, Bonjardim; Erna G, Kroon; Paulo CP, Ferreira.

2014-05-07

272

Mycobacteria mobility shift assay: a method for the rapid identification of Mycobacterium tuberculosis and nontuberculous mycobacteria  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The identification of mycobacteria is essential because tuberculosis (TB) and mycobacteriosis are clinically indistinguishable and require different therapeutic regimens. The traditional phenotypic method is time consuming and may last up to 60 days. Indeed, rapid, affordable, specific and easy-to-p [...] erform identification methods are needed. We have previously described a polymerase chain reaction-based method called a mycobacteria mobility shift assay (MMSA) that was designed for Mycobacterium tuberculosis complex (MTC) and nontuberculous mycobacteria (NTM) species identification. The aim of this study was to assess the MMSA for the identification of MTC and NTM clinical isolates and to compare its performance with that of the PRA-hsp65 method. A total of 204 clinical isolates (102 NTM and 102 MTC) were identified by the MMSA and PRA-hsp65. For isolates for which these methods gave discordant results, definitive species identification was obtained by sequencing fragments of the 16S rRNA and hsp65 genes. Both methods correctly identified all MTC isolates. Among the NTM isolates, the MMSA alone assigned 94 (92.2%) to a complex or species, whereas the PRA-hsp65 method assigned 100% to a species. A 91.5% agreement was observed for the 94 NTM isolates identified by both methods. The MMSA provided correct identification for 96.8% of the NTM isolates compared with 94.7% for PRA-hsp65. The MMSA is a suitable auxiliary method for routine use for the rapid identification of mycobacteria.

Letícia Muraro, Wildner; Maria Luiza, Bazzo; Susie Coutinho, Liedke; Christiane Lourenço, Nogueira; Gabriela, Segat; Simone Gonçalves, Senna; Aline Daiane, Schlindwein; Jaquelline Germano de, Oliveira; Darcita B, Rovaris; Claudio A, Bonjardim; Erna G, Kroon; Paulo CP, Ferreira.

2014-06-01

273

Trichoderma genes  

Energy Technology Data Exchange (ETDEWEB)

Described herein are novel gene sequences isolated from Trichoderma reesei. Two genes encoding proteins comprising a cellulose binding domain, one encoding an arabionfuranosidase and one encoding an acetylxylanesterase are described. The sequences, CIP1 and CIP2, contain a cellulose binding domain. These proteins are especially useful in the textile and detergent industry and in pulp and paper industry.

Foreman, Pamela (Los Altos, CA); Goedegebuur, Frits (Vlaardingen, NL); Van Solingen, Pieter (Naaldwijk, NL); Ward, Michael (San Francisco, CA)

2012-06-19

274

Enfermedades micobacterianas diseminadas en pacientes con VIH/SIDA. Evaluación de los hemocultivos por método rápido / Disseminated mycobacterial infections in patients with HIV/AIDS. Evaluation of blood cultures  

Scientific Electronic Library Online (English)

Full Text Available SciELO Argentina | Language: Spanish Abstract in spanish Mil cuarenta hemocultivos correspondientes a 451 enfermos uruguayos con SIDA y diagnóstico clínico de micobacteriosis diseminada fueron evaluados entre 1999 y 2003. Las muestras fueron procesadas en el Centro de Referencia Nacional para Micobacterias (Montevideo, Uruguay), utilizando el sistema de h [...] emocultivos automatizado para micobacterias MB - BacT (BioMérieux). Se detectaron 45 muestras positivas (4,3%) correspondientes a 26 enfermos (promedio 2,3 muestras por paciente). En 10/26 casos se identificó M. avium complex (MAC) y en 13/26 el germen aislado fue M. tuberculosis. El tiempo medio de incubación fue de 12,4 días (intervalo 6-19 días) para MAC y de 22,6 días (intervalo 7-35 días) para M. tuberculosis. El hemocultivo ha demostrado ser la mejor muestra para la confirmación bacteriológica de las enfermedades micobacterianas diseminadas cuando se estudian por lo menos 2 muestras por paciente. La frecuencia de aislamientos de M. tuberculosis y MAC aislados en pacientes con SIDA en Uruguay, corresponde a la de un país con una moderada prevalencia de tuberculosis. Abstract in english One thousand-forty blood cultures corresponding to 451 Uruguayan patients with AIDS and clinic diagnosis of disseminated mycobacterial infection were evaluated between 1999 and 2003. Samples were processed in the NationalReferenceCenter for Mycobacteria (Montevideo, Uruguay), using the automated blo [...] od culture system for mycobacteria MB -BacT (BioMérieux). Forty-five positive samples were detected (4.3%) corresponding to 26 patients with AIDS (average 2.3 samples per patient). In 10/26 patients M. avium complex (MAC) was identified and in 13/26 the isolated germ was M. tuberculosis. The average time of incubation was of 12.4 days (range 6-19 days) for MAC and of 22.6 days (range 7-35 days) for M. tuberculosis. Blood culture has demonstrated to be the best sample for the bacteriological confirmation of the disseminated mycobacterial infections when at least 2 samples by patient are studied. The frequency of isolates of M. tuberculosis and MAC in AIDS patients is according with a moderate prevalence of tuberculosis in Uruguay.

C., Coitinho; E., Brandes; M., Pardiñas; C., Rivas.

275

Enfermedades micobacterianas diseminadas en pacientes con VIH/SIDA. Evaluación de los hemocultivos por método rápido / Disseminated mycobacterial infections in patients with HIV/AIDS. Evaluation of blood cultures  

Scientific Electronic Library Online (English)

Full Text Available SciELO Argentina | Language: Spanish Abstract in spanish Mil cuarenta hemocultivos correspondientes a 451 enfermos uruguayos con SIDA y diagnóstico clínico de micobacteriosis diseminada fueron evaluados entre 1999 y 2003. Las muestras fueron procesadas en el Centro de Referencia Nacional para Micobacterias (Montevideo, Uruguay), utilizando el sistema de h [...] emocultivos automatizado para micobacterias MB - BacT (BioMérieux). Se detectaron 45 muestras positivas (4,3%) correspondientes a 26 enfermos (promedio 2,3 muestras por paciente). En 10/26 casos se identificó M. avium complex (MAC) y en 13/26 el germen aislado fue M. tuberculosis. El tiempo medio de incubación fue de 12,4 días (intervalo 6-19 días) para MAC y de 22,6 días (intervalo 7-35 días) para M. tuberculosis. El hemocultivo ha demostrado ser la mejor muestra para la confirmación bacteriológica de las enfermedades micobacterianas diseminadas cuando se estudian por lo menos 2 muestras por paciente. La frecuencia de aislamientos de M. tuberculosis y MAC aislados en pacientes con SIDA en Uruguay, corresponde a la de un país con una moderada prevalencia de tuberculosis. Abstract in english One thousand-forty blood cultures corresponding to 451 Uruguayan patients with AIDS and clinic diagnosis of disseminated mycobacterial infection were evaluated between 1999 and 2003. Samples were processed in the NationalReferenceCenter for Mycobacteria (Montevideo, Uruguay), using the automated blo [...] od culture system for mycobacteria MB -BacT (BioMérieux). Forty-five positive samples were detected (4.3%) corresponding to 26 patients with AIDS (average 2.3 samples per patient). In 10/26 patients M. avium complex (MAC) was identified and in 13/26 the isolated germ was M. tuberculosis. The average time of incubation was of 12.4 days (range 6-19 days) for MAC and of 22.6 days (range 7-35 days) for M. tuberculosis. Blood culture has demonstrated to be the best sample for the bacteriological confirmation of the disseminated mycobacterial infections when at least 2 samples by patient are studied. The frequency of isolates of M. tuberculosis and MAC in AIDS patients is according with a moderate prevalence of tuberculosis in Uruguay.

C., Coitinho; E., Brandes; M., Pardiñas; C., Rivas.

2005-12-01

276

Enfermedades micobacterianas diseminadas en pacientes con VIH/SIDA. Evaluación de los hemocultivos por método rápido Disseminated mycobacterial infections in patients with HIV/AIDS. Evaluation of blood cultures  

Directory of Open Access Journals (Sweden)

Full Text Available Mil cuarenta hemocultivos correspondientes a 451 enfermos uruguayos con SIDA y diagnóstico clínico de micobacteriosis diseminada fueron evaluados entre 1999 y 2003. Las muestras fueron procesadas en el Centro de Referencia Nacional para Micobacterias (Montevideo, Uruguay, utilizando el sistema de hemocultivos automatizado para micobacterias MB - BacT (BioMérieux. Se detectaron 45 muestras positivas (4,3% correspondientes a 26 enfermos (promedio 2,3 muestras por paciente. En 10/26 casos se identificó M. avium complex (MAC y en 13/26 el germen aislado fue M. tuberculosis. El tiempo medio de incubación fue de 12,4 días (intervalo 6-19 días para MAC y de 22,6 días (intervalo 7-35 días para M. tuberculosis. El hemocultivo ha demostrado ser la mejor muestra para la confirmación bacteriológica de las enfermedades micobacterianas diseminadas cuando se estudian por lo menos 2 muestras por paciente. La frecuencia de aislamientos de M. tuberculosis y MAC aislados en pacientes con SIDA en Uruguay, corresponde a la de un país con una moderada prevalencia de tuberculosis.One thousand-forty blood cultures corresponding to 451 Uruguayan patients with AIDS and clinic diagnosis of disseminated mycobacterial infection were evaluated between 1999 and 2003. Samples were processed in the NationalReferenceCenter for Mycobacteria (Montevideo, Uruguay, using the automated blood culture system for mycobacteria MB -BacT (BioMérieux. Forty-five positive samples were detected (4.3% corresponding to 26 patients with AIDS (average 2.3 samples per patient. In 10/26 patients M. avium complex (MAC was identified and in 13/26 the isolated germ was M. tuberculosis. The average time of incubation was of 12.4 days (range 6-19 days for MAC and of 22.6 days (range 7-35 days for M. tuberculosis. Blood culture has demonstrated to be the best sample for the bacteriological confirmation of the disseminated mycobacterial infections when at least 2 samples by patient are studied. The frequency of isolates of M. tuberculosis and MAC in AIDS patients is according with a moderate prevalence of tuberculosis in Uruguay.

C. Coitinho

2005-12-01

277

Inaccuracy of Single-Target Sequencing for Discriminating Species of the Mycobacterium abscessus Group?  

Science.gov (United States)

We determined nucleotide sequences of rpoB, hsp65, and sodA in 59 clinical isolates (from 58 patients) of the Mycobacterium abscessus group. Identification to the species level, based on three target genes, was concordant for 44 isolates (25 M. abscessus, 13 Mycobacterium massiliense, and 6 Mycobacterium bolletii isolates) and discordant for 15 isolates which had “interspecific composite patterns.” Sequence analysis of five housekeeping genes also showed composite patterns in 8 of these 15 isolates. PMID:19515839

Macheras, Edouard; Roux, Anne-Laure; Ripoll, Fabienne; Sivadon-Tardy, Valerie; Gutierrez, Cristina; Gaillard, Jean-Louis; Heym, Beate

2009-01-01

278

A Multiplex Approach to Molecular Detection of Brucella abortus and/or Mycobacterium bovis Infection in Cattle  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A multiplex amplification and detection platform for the diagnosis of Mycobacterium bovis and Brucella abortus infection simultaneously in bovine milk and nasal secretions was developed. This system (designated the bovine pathogen detection assay [BPDA]-PCR) consists of duplex amplification of species-specific targets (a region of the BCSP31K gene of B. abortus and a repeat-sequence region in the hsp65 gene of M. bovis, respectively). This is followed by a solid-phase probe capture hybridizat...

Sreevatsan, Srinand; Bookout, Jack B.; Ringpis, Fidel; Perumaalla, Veera S.; Ficht, Thomas A.; Adams, L. Garry; Hagius, Sue D.; Elzer, Philip H.; Bricker, Betsy J.; Kumar, Girish K.; Rajasekhar, M.; Isloor, Srikrishna; Barathur, Raj R.

2000-01-01

279

A Second Endolysin Gene Is Fully Embedded In-Frame with the lysA Gene of Mycobacteriophage Ms6  

Science.gov (United States)

Mycobacteriophages are dsDNA viruses that infect mycobacterial hosts. The mycobacteriophage Ms6 accomplishes lysis by producing two cell wall hydrolytic enzymes, Lysin A (LysA) that possesses a central peptidoglycan recognition protein (PGRP) super-family conserved domain with the amidase catalytic site, that cleaves the amide bond between the N-acetylmuramic acid and L-alanine residues in the oligopeptide crosslinking chains of the peptidoglycan and Lysin B (LysB) a mycolylarabinogalactan esterase that hydrolyzes the mycolic acids from the mycolyl-arabinogalactan-peptidoglycan complex. Examination of the endolysin (lysA) DNA sequence revealed the existence of an embedded gene (lysA241) encoded in the same reading frame and preceded by a consensus ribosome-binding site. In the present work we show that, even though lysA is essential for Ms6 viability, phage mutants that express only the longer (Lysin384) or the shorter (Lysin241) endolysin are viable, but defective in the normal timing, progression and completion of host cell lysis. In addition, both endolysins have peptidoglycan hydrolase activity and demonstrated broad growth inhibition activity against various Gram-positive bacteria and mycobacteria. PMID:21694774

Catalao, Maria Joao; Milho, Catarina; Gil, Filipa; Moniz-Pereira, Jose; Pimentel, Madalena

2011-01-01

280

Attention Genes  

Science.gov (United States)

A major problem for developmental science is understanding how the cognitive and emotional networks important in carrying out mental processes can be related to individual differences. The last five years have seen major advances in establishing links between alleles of specific genes and the neural networks underlying aspects of attention. These…

Posner, Michael I.; Rothbart, Mary K.; Sheese, Brad E.

2007-01-01

 
 
 
 
281

Genotypic characterization of five subspecies of Mycobacterium kansasii.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Different molecular typing methods including restriction fragment length polymorphism (RFLP) analysis with the major polymorphic tandem repeat (MPTR) probe and the IS1652 probe, pulsed-field gel electrophoresis (PFGE), amplified fragment length polymorphism (AFLP) analysis, and PCR restriction analysis of the hsp-65 gene (PRA) were applied to clinical and water isolates of Mycobacterium kansasii. RFLP with the MPTR probe, PRA, PFGE, and AFLP analysis revealed five homogeneous clusters which a...

Picardeau, M.; Prod Hom, G.; Raskine, L.; Lepennec, M. P.; Vincent, V.

1997-01-01

282

Comparison of a Semiautomated Commercial Repetitive-Sequence-Based PCR Method with Spoligotyping, 24-Locus Mycobacterial Interspersed Repetitive-Unit-Variable-Number Tandem-Repeat Typing, and Restriction Fragment Length Polymorphism-Based Analysis of IS6110 for Mycobacterium tuberculosis Typing.  

Science.gov (United States)

Fifty-two multidrug-resistant isolates of Mycobacterium tuberculosis representative of the currently predominant lineages in France were analyzed using repetitive-sequence-based PCR (rep-PCR) DiversiLab (DL), spoligotyping, 24-locus mycobacterial interspersed repetitive-unit-variable-number tandem-repeat typing (MIRU-VNTR), and restriction fragment length polymorphism of IS6110 (IS6110-RFLP). DL, as opposed to MIRU-VNTR and IS6110-RFLP analysis, did not allow discrimination among half of the isolates, an indication of comparatively lower resolving power. PMID:25210067

Brossier, F; Sola, C; Millot, G; Jarlier, V; Veziris, N; Sougakoff, W

2014-11-01

283

Genes and Hearing Loss  

Science.gov (United States)

Genes and Hearing Loss Genes and Hearing Loss Patient Health Information News media interested in covering the ... mutation may only have dystopia canthorum. How Do Genes Work? Genes are a road map for the ...

284

Evaluating gene × gene and gene × smoking interaction in rheumatoid arthritis using candidate genes in GAW15  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract We examined the potential gene × gene interactions and gene × smoking interactions in rheumatoid arthritis (RA) using the candidate gene data sets provided by Genetic Analysis Workshop 15 Problem 2. The multifactor dimensionality reduction (MDR) method was used to test gene × gene interactions among candidate genes. The case-only sample was used to test gene × smoking interactions. The best predictive model was the single-locus model with single-nucleotide polymorphism ...

Mei Ling; Li Xiaohui; Yang Kai; Cui Jinrui; Fang Belle; Guo Xiuqing; Rotter Jerome I

2007-01-01

285

Overexpression of the Salmonella KdpF membrane peptide modulates expression of kdp genes and intramacrophage growth.  

Science.gov (United States)

Membrane peptides appear as an emerging class of regulatory molecules in bacteria, which can interact with membrane proteins, including transporters and sensor kinases. The KdpF peptide, which is cotranscribed with kdpABC genes and regulated by the KdpDE two-component system, is supposed to stabilize the KdpABC potassium transporter complex but may also exhibit unsuspected regulatory function(s). The mycobacterial KdpF can interact with the KdpD histidine kinase, and kdpF overexpression has been shown to reduce intramacrophage replication of Mycobacterium bovis BCG. In this study, we investigated whether KdpF displays similar behavior in another intracellular pathogen, Salmonella enterica serovar Typhimurium. We show that Salmonella KdpF can interact with KdpD in a bacterial two-hybrid assay. We have constructed a Salmonella strain overexpressing kdpF, and we have investigated expression of the kdp regulon, as well as intramacrophage survival. We show that kdpF overexpression reduces expression of kdpA and kdpD genes under potassium limitation. Moreover, kdpF overexpression increases intramacrophage multiplication of S. Typhimurium. Hence, our results indicate that KdpF can play a regulatory role in S. Typhimurium, modulating kdp gene expression and intramacrophage survival, but in a way that differs from the one reported for M. bovis BCG. PMID:25197761

Gannoun-Zaki, Laila; Belon, Claudine; Dupont, Christian; Hilbert, Friederike; Kremer, Laurent; Blanc-Potard, Anne-Béatrice

2014-10-01

286

Gene expression and gene therapy imaging  

Energy Technology Data Exchange (ETDEWEB)

The fast growing field of molecular imaging has achieved major advances in imaging gene expression, an important element of gene therapy. Gene expression imaging is based on specific probes or contrast agents that allow either direct or indirect spatio-temporal evaluation of gene expression. Direct evaluation is possible with, for example, contrast agents that bind directly to a specific target (e.g., receptor). Indirect evaluation may be achieved by using specific substrate probes for a target enzyme. The use of marker genes, also called reporter genes, is an essential element of MI approaches for gene expression in gene therapy. The marker gene may not have a therapeutic role itself, but by coupling the marker gene to a therapeutic gene, expression of the marker gene reports on the expression of the therapeutic gene. Nuclear medicine and optical approaches are highly sensitive (detection of probes in the picomolar range), whereas MRI and ultrasound imaging are less sensitive and require amplification techniques and/or accumulation of contrast agents in enlarged contrast particles. Recently developed MI techniques are particularly relevant for gene therapy. Amongst these are the possibility to track gene therapy vectors such as stem cells, and the techniques that allow spatiotemporal control of gene expression by non-invasive heating (with MRI guided focused ultrasound) and the use of temperature sensitive promoters. (orig.)

Rome, Claire; Couillaud, Franck [Universite Victor Segalen, Laboratory for Molecular and Functional Imaging, From Physiology to Therapy ERT CNRS, Bordeaux (France); Moonen, Chrit T.W. [Universite Victor Segalen, Laboratory for Molecular and Functional Imaging, From Physiology to Therapy ERT CNRS, Bordeaux (France); Universite Victor Segalen, Imagerie Moleculaire et Fonctionnelle, ERT CNRS, Bordeaux (France)

2007-02-15

287

Gene expression and gene therapy imaging  

International Nuclear Information System (INIS)

The fast growing field of molecular imaging has achieved major advances in imaging gene expression, an important element of gene therapy. Gene expression imaging is based on specific probes or contrast agents that allow either direct or indirect spatio-temporal evaluation of gene expression. Direct evaluation is possible with, for example, contrast agents that bind directly to a specific target (e.g., receptor). Indirect evaluation may be achieved by using specific substrate probes for a target enzyme. The use of marker genes, also called reporter genes, is an essential element of MI approaches for gene expression in gene therapy. The marker gene may not have a therapeutic role itself, but by coupling the marker gene to a therapeutic gene, expression of the marker gene reports on the expression of the therapeutic gene. Nuclear medicine and optical approaches are highly sensitive (detection of probes in the picomolar range), whereas MRI and ultrasound imaging are less sensitive and require amplification techniques and/or accumulation of contrast agents in enlarged contrast particles. Recently developed MI techniques are particularly relevant for gene therapy. Amongst these are the possibility to track gene therapy vectors such as stem cells, and the techniques that allow spatiotemporal control of gene expression by non-invasive heating (with MRI guided focused ultrasound) and the use of temperature sensitive promoters. (orig.)

288

Deep stromal mycobacterial keratitis: viable bacteria after six months of treatment: case report and literature review Ceratite estromal profunda por micobactéria: bactéria viável após seis meses de tratamento: relato de caso e revisão da literatura  

Directory of Open Access Journals (Sweden)

Full Text Available To report the presence of viable mycobacteria in a patient with keratitis treated for 6 months. Species identification was performed using the PRA method (polymerase chain reaction followed by restriction endonuclease analysis. Clonality was evaluated with RAPD (randomly amplified polymorphic DNA and ERIC-PCR (enterobacterial repetitive intergenic consensus - polymerase chain reaction methods. The patient reported trauma due to a metallic foreign body 3 weeks prior to presentation. Initial corneal scraping cultures revealed Mycobacterium abscessus. After 6 months of topical and systemic treatment the patient presented with no active inflammation and was considered clinically cured. An optic penetrating keratoplasty was performed. Culture of the excised cornea revealed Mycobacterium abscessus. Both isolates had the same clonal origin. The most interesting finding of this case report was the positive culture of the excised cornea after 6 months of intensive specific topical therapy. To our knowledge, this is the first report in the literature showing this possibility in the treatment of Mycobacterial keratitis. Thus, Mycobacterium abscessus may present viable bacteria after long-term treatment and should be followed carefully for a long period of time after tapering the medication.O objetivo do caso é descrever a presença de micobactérias viáveis em pacientes com ceratite, 6 meses após tratamento intensivo. A identificação de espécies, foi efetuada usando método PRA (polymerase chain reaction seguida pela restriction endonuclease analysis. Clonalidade foi avaliada pelos métodos RAPD (randomly amplified polymorphic DNA e ERIC-PCR (enterobacterial repetitive intergenic consensus - polymerase chain reaction. Paciente refere trauma com corpo estranho metálico há 3 semanas. A cultura da córnea revelou Mycobacterium abscessus. Após 6 meses de tratamento tópico e sistêmico, paciente apresentava-se sem inflamação, sendo considerado clinicamente curado. Realizou-se então, uma ceratoplastia penetrante com intuitos ópticos. A cultura da córnea transplantada revelou micobactérias de mesma origem clonal. O achado mais interessante neste relato, foi a positividade da cultura da córnea transplantada após 6 meses de intenso tratamento específico. Ao nosso conhecimento, esse é o primeiro caso relatado na literatura mostrando essa possibilidade em tratamento de ceratites por micobactérias. Assim, os pacientes com ceratite por Mycobacterium abscessus podem apresentar bactérias viáveis após longo tempo de tratamento específico e precisam ser seguidos cuidadosamente por um longo período de tempo.

Filipe Accioly de Gusmão

2005-08-01

289

Diagnóstico de la infección micobacteriana diseminada: evaluación de un método sencillo y barato para países en desarrollo Diagnosis of disseminated mycobacterial infection: testing a simple and inexpensive method for use in developing countries  

Directory of Open Access Journals (Sweden)

Full Text Available Con el desarrollo de la epidemia del síndrome de inmunodeficiencia adquirida (sida, el aislamiento de micobacterias de la sangre se ha convertido en un problema habitual de los laboratorios clínicos. En el presente estudio se evaluaron dos métodos para aislar micobacterias en muestras de sangre de pacientes de sida: 1 la inoculación directa en un medio bifásico y 2 un método no comercializado de lisis por centrifugación. A cada uno de los 50 pacientes de sida con sospecha de enfermedad micobacteriana diseminada se le extrajeron tres muestras de sangre consecutivas a intervalos de 15 minutos. En 70 de 138 muestras de sangre obtenidas de 30 (60% pacientes se detectó crecimiento de micobacterias. A partir de estos cultivos, en 19 pacientes se aisló Mycobacterium tuberculosis y en 11 (37%, el complejo Mycobacterium avium. Los cultivos en que se utilizó el método de lisis por centrifugación fueron positivos en 54% de los pacientes, mientras que esta cifra se redujo a 44% en los cultivos en que se usó el método bifásico (P > 0,05. El porcentaje de muestras positivas al complejo M. avium fue mayor con el método de centrifugación por lisis (91% que con el de inoculación directa en medio bifásico (45,4% (P 0,05. La técnica no comercializada de centrifugación por lisis es barata, fiable y puede constituir un método alternativo para el diagnóstico de micobacteriemia en países en desarrollo.With the development of the acquired immunodeficiency syndrome (AIDS epidemic, the isolation of mycobacteria from blood has become a common problem for clinical laboratories. In this study two methods were used for the recovery of mycobacteria from blood specimens obtained from AIDS patients: (1 direct inoculation in biphasic medium, and (2 a noncommercial lysis-centrifugaton method. A total of three consecutive blood samples were taken at 15-minute intervals from each of 50 AIDS patients with clinical suspicion of disseminated mycobacterial disease. Mycobacterium growth was noted in 70/138 blood specimens from 30 (60% patients. These cultures yielded Mycobacterium tuberculosis in 19 (63% and Mycobacterium avium complex organisms in 11 (37% patients. Cultures using the lysis-centrifugation method were positive in 54% of the patients, while cultures using biphasic medium were positive in 44% (P > 0,05. The positivity for M. avium complex was higher with lysis-centrifugation (91% than with biphasic medium (45,4% (P 0,05. The use of a noncommercial lysis-centrifugation technique is inexpensive, reliable, and can be an alternative method for the diagnosis of mycobacteremia in developing countries.

F. C .O. Fandinho

1998-07-01

290

Imaging gene expression in gene therapy  

Energy Technology Data Exchange (ETDEWEB)

Full text. Gene therapy can be used to introduce new genes, or to supplement the function of indigenous genes. At the present time, however, there is non-invasive test to demonstrate efficacy of the gene transfer and expression processes. It has been postulated that scintigraphic imaging can offer unique information on both the site at which the transferred gene is expressed, and the degree of expression, both of which are critical issue for safety and clinical efficacy. Many current studies are based on `suicide gene therapy` of cancer. Cells modified to express these genes commit metabolic suicide in the presence of an enzyme encoded by the transferred gene and a specifically-convertible pro drug. Pro drug metabolism can lead to selective metabolic trapping, required for scintigraphy. Herpes simplex virus type-1 thymidine kinase (H S V-1 t k{sup +}) has been use for `suicide` in vivo tumor gene therapy. It has been proposed that radiolabelled nucleosides can be used as radiopharmaceuticals to detect H S V-1 t k{sup +} gene expression where the H S V-1 t k{sup +} gene serves a reporter or therapeutic function. Animal gene therapy models have been studied using purine-([{sup 18} F]F H P G; [{sup 18} F]-A C V), and pyrimidine- ([{sup 123}/{sup 131} I]I V R F U; [{sup 124}/{sup 131I}]) antiviral nucleosides. Principles of gene therapy and gene therapy imaging will be reviewed and experimental data for [{sup 123}/{sup 131I}]I V R F U imaging with the H S V-1 t k{sup +} reporter gene will be presented

Wiebe, Leonard I. [Alberta Univ., Edmonton (Canada). Noujaim Institute for Pharmaceutical Oncology Research

1997-12-31

291

Imaging gene expression in gene therapy  

International Nuclear Information System (INIS)

Full text. Gene therapy can be used to introduce new genes, or to supplement the function of indigenous genes. At the present time, however, there is non-invasive test to demonstrate efficacy of the gene transfer and expression processes. It has been postulated that scintigraphic imaging can offer unique information on both the site at which the transferred gene is expressed, and the degree of expression, both of which are critical issue for safety and clinical efficacy. Many current studies are based on 'suicide gene therapy' of cancer. Cells modified to express these genes commit metabolic suicide in the presence of an enzyme encoded by the transferred gene and a specifically-convertible pro drug. Pro drug metabolism can lead to selective metabolic trapping, required for scintigraphy. Herpes simplex virus type-1 thymidine kinase (H S V-1 t k+) has been use for 'suicide' in vivo tumor gene therapy. It has been proposed that radiolabelled nucleosides can be used as radiopharmaceuticals to detect H S V-1 t k+ gene expression where the H S V-1 t k+ gene serves a reporter or therapeutic function. Animal gene therapy models have been studied using purine-([18 F]F H P G; [18 F]-A C V), and pyrimidine- ([123/131 I]I V R F U; [124/131I]) antiviral nucleosides. Principles of gene therapy and gene therapy imaging will be reviewed and experimental data for [123/131rimental data for [123/131I]I V R F U imaging with the H S V-1 t k+ reporter gene will be presented

292

Mycobacterial subcutaneous arteritis Arterite subcutânea por micobactéria  

Directory of Open Access Journals (Sweden)

Full Text Available The authors report three patients with subcutaneous erythematous nodules in different phases of development, inespecific systemic symptoms, positive PPD test, and normal chest X-rays. The histopathological study of the older nodules showed a granulomatous arteritis with a few acid-fast bacilli in the vascular wall. The nodules at an early phase showed an inespecific panniculitis with some acid-fast bacilli in apparently normal cutaneous vessels. These findings suggest that the mycobacterium has a vascular tropism and may cause a primary granulomatous arteritis.Os autores descrevem três casos de pacientes com nódulos subcutâneos em diferentes fases de evolução, com sintomas sistêmicos inespe-cíficos, PPD positivo e raio-X de tórax normal. O estudo anátomo-patológico dos nódulos antigos mostrou arterite granulomatosa e com raros bacilos álcool-ácido resistentes na parede vascular; os nódulos recentes mostraram paniculite inespecífica com alguns bacilos álcool-ácido resistentes na parede de vasos cutâneos aparentemente normais. Esses achados sugerem que a micobactéria tem um tropismo vascular e pode causar arterite granulomatosa.

Consuelo Junqueira Rodrigues

1990-10-01

293

Mycobacterial tuberculosis superimposed on a Warthin tumor.  

Science.gov (United States)

The concomitant occurrence of tuberculosis infection within a Warthin tumor is extremely rare, as only 6 cases have been previously reported in the English-language literature. We report a new case in a 92-year-old man, who presented with a 20-year history of a painless swelling in the right infra-auricular area that had recently become painful and larger. The patient had no history of tuberculosis, weight loss, or chronic cough. The fluctuant mass was aspirated, but histopathology and routine culture were negative. Computed tomography identified a 5-cm, heterogeneous, enhancing mass with multiple, variably sized, low-density areas without surrounding edema in the area of the right parotid gland. Complete excision was performed to relieve the patient's symptoms. Histopathology diagnosed an acid-fast bacillus infection within a Warthin tumor. On polymerase chain reaction testing, formalin-fixed, paraffin-embedded tissue was negative for tuberculosis, but subsequent culture identified Mycobacterium tuberculosis. Initially, the patient refused antituberculosis therapy, but he relented when miliary pulmonary tuberculosis was diagnosed 11 weeks postoperatively. PMID:22614566

Wu, Kang-Chao; Chen, Bo-Nien

2012-05-01

294

Cervicofacial nontuberculous mycobacterial lymphadenitis in children  

DEFF Research Database (Denmark)

Nontuberculous mycobacteria are ubiquitous organisms readily isolated from natural waters, drinking water systems and soil. They form a continuous challenge to the human immune system which becomes apparent in patients with impaired immunity. However, most infections occur in seemingly healthy children. The clinical presentation consists of a unilateral, non-tender, persistent, cervical lymphadenopathy without systemic illness. Fistula formation may occur.

Iversen, Rikke Haahr; Illum, Peter

2012-01-01

295

Drug Targets in Mycobacterial Sulfur Metabolism  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The identification of new antibacterial targets is urgently needed to address multidrug resistant and latent tuberculosis infection. Sulfur metabolic pathways are essential for survival and the expression of virulence in many pathogenic bacteria, including Mycobacterium tuberculosis. In addition, microbial sulfur metabolic pathways are largely absent in humans and therefore, represent unique targets for therapeutic intervention. In this review, we summarize our current understanding of the en...

Bhave, Devayani P.; Muse, Wilson B.; Carroll, Kate S.

2007-01-01

296

Mycobacterial infections in organ transplant recipients.  

Science.gov (United States)

Tuberculosis has a major adverse impact on solid organ transplant recipients; this article attempts to define this fact. The prevalence of posttransplant tuberculosis is increasing globally and currently is 13.7% at our center. The transplant surgery divides the continuum of pretransplant tuberculosis and posttransplant tuberculosis; immunosuppression accounts for a greater severity of the latter. Cyclosporin and tacrolimus are associated with an earlier onset of tuberculosis when compared with prednisolone and azathioprine immunosuppression. Disseminated disease is more common in nonrenal transplants. The risk for developing posttransplant tuberculosis in renal transplant recipients increased 2.25 times independently with cytomegalovirus (CMV) and twice with chronic liver disease; OKT3 treatment enhances the risk 1.8-fold. Tuberculosis occurring after 2 years of transplantation, diabetes mellitus, posttransplant diabetes mellitus, chronic liver disease, CMV, and deep mycoses each independently confer a risk, 1.5-times or higher, for death. Disseminated disease entails a 2-fold risk. Treatment with or without rifampicin is possible; the former is associated with a higher risk for allograft rejection. Isoniazid prophylaxis is recommended for high-risk patients with apparent clinical efficacy. However, in endemic areas, attendant liver disease makes it a difficult goal. PMID:12497544

John, George T; Shankar, Viswanathan

2002-12-01

297

Plasmid instability when the hsp60 gene promoter is used to express the protective non-toxic fragment B of the diphtheria toxin in recombinant BCG  

Directory of Open Access Journals (Sweden)

Full Text Available The genetic modification of the live attenuated Mycobacterium bovis BCG to deliver a protective Corynebacterium diphtheriae antigen in vivo could be a safer and less costly alternative to the new and more expensive DTP vaccines available today, in particular to third world-countries. The stability of expression of heterologous antigens in BCG, however, is a major challenge to the use of live recombinant bacteria in vaccine development and appears to be dependent to a certain extent, on a genetic compatibility between the expression cassette within the plasmid construct and the mycobacterium host. In the quest for the best recombinant BCG transformant to express the dtb gene of C. diphtheriae we generated two new rBCG strains by transforming the Moreau substrain of BCG with the mycobacterial expression vectors pUS973 and pUS977, each one carrying a different promoter to drive the expression of the target antigen. After transformation recombinant BCG clones were selected on Middlebrook 7H10 kanamycin Agar plates, expanded in Middlebrook 7H9 kanamycin Broth and analyzed by agarose gel electrophoresis and immunoblotting. rBCGs transformed with the construct carrying the weak PAN promoter from M. paratuberculosis stably expressed the dtb gene. Conversely, rBCGs transformed with the construct carrying the strong mycobacterium hsp60 promoter were unstable and consequently unfit for the expression of the C. diphtheriae gene.

Dilzamar V. Nascimento

2013-04-01

298

Autism and Genes  

Science.gov (United States)

This document defines and discusses autism and how genes play a role in the condition. Answers to the following questions are covered: (1) What are genes? (2) What is autism? (3) What causes autism? (4) Why study genes to learn about autism? (5) How do researchers look for the genes involved in autism? (screen the whole genome; conduct cytogenetic…

National Institutes of Health, 2005

2005-01-01

299

Principles of gene therapy  

Directory of Open Access Journals (Sweden)

Full Text Available Genes are specific sequences of bases that encode instructions to make proteins. When genes are altered so that encoded proteins are unable to carry out their normal functions, genetic disorders can result. Gene therapy is designed to introduce genetic material into cells to compensate for abnormal genes or to make a beneficial protein. This article reviews the fundamentals in gene therapy and its various modes of administration with an insight into the role of gene therapy in Periodontics and future percepts and the technical and ethical issues of using gene therapy.

Mammen Biju

2007-01-01

300

Keratinocyte gene transfer and gene therapy.  

Science.gov (United States)

Gene therapy has moved beyond the pre-clinical stage to the treatment of a variety of inherited and acquired diseases. For such therapy to be successful, genes must be efficiently delivered to target cells and gene products must be expressed for prolonged periods of time without toxic effects to the host. This may be achieved by means of an in vivo strategy where genes are transferred directly into a host cell, or by means of an ex vivo approach through which cells are removed, cultured, targeted for gene delivery, and grafted back to the host. Several obstacles continue to delay safe and effective clinical application of gene therapy in a variety of target cells. The limited survival of transplanted cells, transient expression of transferred genes, and difficulties in targeting stem cells are technical issues requiring further investigation. Epidermal and oral keratinocytes are potential vehicles for gene therapy. Several features of these tissues can be utilized to achieve delivery of therapeutic gene products for local or systemic delivery. These qualities include: (1) the presence of stem cells; (2) the cell-, strata-, and site-specific regulation of keratinocyte gene expression; (3) tissue accessibility; and (4) secretory capacity. Such features can be exploited by the use of gene therapy strategies to facilitate: (1) identification, enrichment, and targeting of stem cells to ensure the continued presence of the transferred gene; (2) high-level and persistent transgene expression using keratinocyte-specific promoters; (3) tissue access needed for culture and grafting for ex vivo therapy and direct in vivo gene transfer; (4) secretion of transgene product for local or systemic delivery; and (5) monitoring of genetically modified tissue and removal if treatment termination is required. Optimal gene therapy strategies are being tested in a variety of tissues to treat dominant and recessive genetic disorders as well as acquired diseases such as neoplasia and infectious disease. This experience provides a basis for the application of such clinical studies to a spectrum of diseases effecting epidermal and oral keratinocytes. Gene therapy is in an early stage yet holds great promise for its ultimate clinical application. PMID:8909878

Garlick, J A; Fenjves, E S

1996-01-01

 
 
 
 
301

Human Gene Therapy: Genes without Frontiers?  

Science.gov (United States)

Describes the latest advancements and setbacks in human gene therapy to provide reference material for biology teachers to use in their science classes. Focuses on basic concepts such as recombinant DNA technology, and provides examples of human gene therapy such as severe combined immunodeficiency syndrome, familial hypercholesterolemia, and…

Simon, Eric J.

2002-01-01

302

Discovering genes underlying QTL  

International Nuclear Information System (INIS)

A map-based approach has allowed scientists to discover few genes at a time. In addition, the reproductive barrier between cultivated rice and wild relatives has prevented us from utilizing the germ plasm by a map-based approach. Most genetic traits important to agriculture or human diseases are manifested as observable, quantitative phenotypes called Quantitative Trait Loci (QTL). In many instances, the complexity of the phenotype/genotype interaction and the general lack of clearly identifiable gene products render the direct molecular cloning approach ineffective, thus additional strategies like genome mapping are required to identify the QTL in question. Genome mapping requires no prior knowledge of the gene function, but utilizes statistical methods to identify the most likely gene location. To completely characterize genes of interest, the initially mapped region of a gene location will have to be narrowed down to a size that is suitable for cloning and sequencing. Strategies for gene identification within the critical region have to be applied after the sequencing of a potentially large clone or set of clones that contains this gene(s). Tremendous success of positional cloning has been shown for cloning many genes responsible for human diseases, including cystic fibrosis and muscular dystrophy as well as plant disease resistance genes. Genome and QTL mapping, positional cloning: the pre-genomics era, comparative approaches to gene identification, and positionalhes to gene identification, and positional cloning: the genomics era are discussed in the report. (M. Suetake)

303

Tumor targeted gene therapy  

International Nuclear Information System (INIS)

Knowledge of molecular mechanisms governing malignant transformation brings new opportunities for therapeutic intervention against cancer using novel approaches. One of them is gene therapy based on the transfer of genetic material to an organism with the aim of correcting a disease. The application of gene therapy to the cancer treatment had led to the development of new experimental approaches such as suicidal gene therapy, inhibition of oncogenes and restoration of tumor-suppressor genes. Suicidal gene therapy is based on the expression in tumor cells of a gene encoding an enzyme that converts a prodrug into a toxic product. Representative suicidal genes are Herpes simplex virus type 1 thymidine kinase (HSV1-tk) and cytosine deaminase (CD). Especially, physicians and scientists of nuclear medicine field take an interest in suicidal gene therapy because they can monitor the location and magnitude, and duration of expression of HSV1-tk and CD by PET scanner

304

Tumor targeted gene therapy  

Energy Technology Data Exchange (ETDEWEB)

Knowledge of molecular mechanisms governing malignant transformation brings new opportunities for therapeutic intervention against cancer using novel approaches. One of them is gene therapy based on the transfer of genetic material to an organism with the aim of correcting a disease. The application of gene therapy to the cancer treatment had led to the development of new experimental approaches such as suicidal gene therapy, inhibition of oncogenes and restoration of tumor-suppressor genes. Suicidal gene therapy is based on the expression in tumor cells of a gene encoding an enzyme that converts a prodrug into a toxic product. Representative suicidal genes are Herpes simplex virus type 1 thymidine kinase (HSV1-tk) and cytosine deaminase (CD). Especially, physicians and scientists of nuclear medicine field take an interest in suicidal gene therapy because they can monitor the location and magnitude, and duration of expression of HSV1-tk and CD by PET scanner.

Kang, Joo Hyun [Korea Institute of Radiological and Medical Science, Seoul (Korea, Republic of)

2006-10-15

305

Your Genes, Your Choices  

Science.gov (United States)

Your Genes, Your Choices describes the Human Genome Project, the science behind it, and the ethical, legal, and social ... Nothing could be further from the truth. Your Genes, Your Choices points out how the progress of ...

306

Radiotechnologies and gene therapy  

International Nuclear Information System (INIS)

Gene therapy is an exciting frontier in medicine today. Radiologist will make an uniquely contribution to these exciting new technologies at every level by choosing sites for targeting therapy, perfecting and establishing routes of delivery, developing imaging strategies to monitor therapy and assess gene expression, developing radiotherapeutic used of gene therapy

307

Discovering genes underlying QTL  

Energy Technology Data Exchange (ETDEWEB)

A map-based approach has allowed scientists to discover few genes at a time. In addition, the reproductive barrier between cultivated rice and wild relatives has prevented us from utilizing the germ plasm by a map-based approach. Most genetic traits important to agriculture or human diseases are manifested as observable, quantitative phenotypes called Quantitative Trait Loci (QTL). In many instances, the complexity of the phenotype/genotype interaction and the general lack of clearly identifiable gene products render the direct molecular cloning approach ineffective, thus additional strategies like genome mapping are required to identify the QTL in question. Genome mapping requires no prior knowledge of the gene function, but utilizes statistical methods to identify the most likely gene location. To completely characterize genes of interest, the initially mapped region of a gene location will have to be narrowed down to a size that is suitable for cloning and sequencing. Strategies for gene identification within the critical region have to be applied after the sequencing of a potentially large clone or set of clones that contains this gene(s). Tremendous success of positional cloning has been shown for cloning many genes responsible for human diseases, including cystic fibrosis and muscular dystrophy as well as plant disease resistance genes. Genome and QTL mapping, positional cloning: the pre-genomics era, comparative approaches to gene identification, and positional cloning: the genomics era are discussed in the report. (M. Suetake)

Vanavichit, Apichart [Kasetsart University, Kamphaengsaen, Nakorn Pathom (Thailand)

2002-02-01

308

Reading and Generalist Genes  

Science.gov (United States)

Twin-study research suggests that many (but not all) of the same genes contribute to genetic influence on diverse learning abilities and disabilities, a hypothesis called "generalist genes". This generalist genes hypothesis was tested using a set of 10 DNA markers (single nucleotide polymorphisms [SNPs]) found to be associated with early reading…

Haworth, Claire M. A.; Meaburn, Emma L.; Harlaar, Nicole; Plomin, Robert

2007-01-01

309

Community structure and PAH ring-hydroxylating dioxygenase genes of a marine pyrene-degrading microbial consortium.  

Science.gov (United States)

Marine microbial consortium UBF, enriched from a beach polluted by the Prestige oil spill and highly efficient in degrading this heavy fuel, was subcultured in pyrene minimal medium. The pyrene-degrading subpopulation (UBF-Py) mineralized 31 % of pyrene without accumulation of partially oxidized intermediates indicating the cooperation of different microbial components in substrate mineralization. The microbial community composition was characterized by culture dependent and PCR based methods (PCR-DGGE and clone libraries). Molecular analyses showed a highly stable community composed by Alphaproteobacteria (84 %, Breoghania, Thalassospira, Paracoccus, and Martelella) and Actinobacteria (16 %, Gordonia). The members of Thalasosspira and Gordonia were not recovered as pure cultures, but five additional strains, not detected in the molecular analysis, that classified within the genera Novosphingobium, Sphingopyxis, Aurantimonas (Alphaproteobacteria), Alcanivorax (Gammaproteobacteria) and Micrococcus (Actinobacteria), were isolated. None of the isolates degraded pyrene or other PAHs in pure culture. PCR amplification of Gram-positive and Gram-negative dioxygenase genes did not produce results with any of the cultured strains. However, sequences related to the NidA3 pyrene dioxygenase present in mycobacterial strains were detected in UBF-Py consortium, suggesting the representative of Gordonia as the key pyrene degrader, which is consistent with a preeminent role of actinobacteria in pyrene removal in coastal environments affected by marine oil spills. PMID:24356981

Gallego, Sara; Vila, Joaquim; Tauler, Margalida; Nieto, José María; Breugelmans, Philip; Springael, Dirk; Grifoll, Magdalena

2014-07-01

310

Gene Gateway: Exploring Genes and Genetic Disorders  

Science.gov (United States)

This collection of guides and tutorials is intended to help users take advantage of of online data sources from the Human Genome Project for learning about genetic disorders, genes, and proteins. Resources include the Gene Gateway Workbook, a downloadable tutorial consisting of activities with screenshots and instructions, that helps new users locate and use genetic-disorder and bioinformatics resources on the web. There are also resources for learning about genes and the proteins they encode; tips, tutorials, and terminology for using selected resources in the Genome Database Guide; a guide to nontechnical resources on genetic disorder descriptions and treatments; a human genome landmarks poster; and others.

311

Cytokine gene expression profiles of bovine dendritic cells after interaction with Mycobacterium avium ssp. paratuberculosis (M.a.p.), Escherichia coli (E. coli) or recombinant M.a.p. heat shock protein 70.  

Science.gov (United States)

Mycobacterium avium paratuberculosis (M.a.p.) resides and replicates in macrophages. Many of the of immune mechanisms aiding M.a.p. survival in the host's cells are known. However, little is known about interactions of M.a.p. with dendritic cells (DC). As DC are important for the induction of protective immunity against infectious diseases, we investigated the interaction of M.a.p. with these cells. Quantitative real-time PCR (RT-PCR) was used to analyse differential expression of cytokine genes after 6 h and 24 h of incubation by immature DC that phagocytosed either M.a.p. or Escherichia coli (E. coli). We hypothesized that phagocytosis of E. coli would induce pro-inflammatory cytokines due to abundant presence of lipopolysaccharide (LPS) and that the cytokine expression profile induced by phagocytosis of live M.a.p. would differ. In addition we hypothesized that incubation of immature DC with rHsp70, an immunodominant antigen of M.a.p., would induce a similar profile of cytokine gene expression as phagocytosis of intact M.a.p. However, phagocytosis of both E. coli and M.a.p. resulted in a cytokine gene expression pattern representative of a (pro-)inflammatory reaction, dominated by strong induction of IL-12 gene expression, that was higher after 24 h than after 6 h of incubation, although the response to M.a.p. was less vigorous than to E. coli. Incubation with rHsp70 resulted in a more inhibitory type of cytokine gene expression, with delayed IL-12 gene expression and downregulation of the genes for IL-1beta and IL-6 after 24 h of incubation. We conclude that bovine DC produce an immuno-stimulatory, anti-mycobacterial response to infection with M.a.p., while Hsp70 potentially contributes to pathogen virulence by allowing the bacteria to invade the host cell. PMID:15946745

Langelaar, Merel F M; Weber, Corinna N; Overdijk, Marije B; Müller, Kerstin E; Koets, Ad P; Rutten, Victor P M G

2005-08-15

312

Modelling prokaryote gene content  

Directory of Open Access Journals (Sweden)

Full Text Available The patchy distribution of genes across the prokaryotes may be caused by multiple gene losses or lateral transfer. Probabilistic models of gene gain and loss are needed to distinguish between these possibilities. Existing models allow only single genes to be gained and lost, despite the empirical evidence for multi-gene events. We compare birth-death models (currently the only widely-used models, in which only one gene can be gained or lost at a time to blocks models (allowing gain and loss of multiple genes within a family. We analyze two pairs of genomes: two E. coli strains, and the distantly-related Archaeoglobus fulgidus (archaea and Bacillus subtilis (gram positive bacteria. Blocks models describe the data much better than birth-death models. Our models suggest that lateral transfers of multiple genes from the same family are rare (although transfers of single genes are probably common. For both pairs, the estimated median time that a gene will remain in the genome is not much greater than the time separating the common ancestors of the archaea and bacteria. Deep phylogenetic reconstruction from sequence data will therefore depend on choosing genes likely to remain in the genome for a long time. Phylogenies based on the blocks model are more biologically plausible than phylogenies based on the birth-death model.

Edward Susko

2006-01-01

313

A Fragment of 21 ORFs Around the Direct Repeat (DR Region of Mycobacterium tuberculosis is Absent From the Other Sequenced Mycobacterial Genomes: Implications for the Evolution of the DR Region  

Directory of Open Access Journals (Sweden)

Full Text Available The direct repeat (DR region is a singular locus of the Mycobacterium tuberculosis complex genome. This region consists of 36 bp repetitive sequences separated by non-repetitive unique spacer sequences. Around this region there are several genes coding for proteins of unknown function. To determine whether the M. smegmatis, M. avium, M. marinum and M. leprae genomes contain sequences and ORFs similar to those of the DR locus of the M. tuberculosis complex, we analysed the corresponding regions in these species. As a first step, some conserved genes that flank the DR genes [Rv2785c (rpsO, Rv2786c (ribF, Rv2790c (ltp1 , Rv2793c (truB, Rv2800, Rv2825, Rv2828, Rv2831 (echA16 , Rv2838 (rbfA and Rv2845 (proS ] were used as markers to locate the corresponding orthologues in M. smegmatis, M. avium, M. marinum and M. leprae in silico. Most of these M. tuberculosis marker genes have highly similar orthologues located in the same order and orientation in the other mycobacteria. In contrast, no orthologues were found for ORFs Rv2801–Rv2824, suggesting that these genes are unique to M. tuberculosis within the genus Mycobacterium.We observed that in M. smegmatis and M. avium, Rv2800 and Rv2825 are adjacent. This observation was experimentally confirmed by PCR. In conclusion, as the DR locus and the ORFs around it are absent in M. smegmatis and M. avium and, as it is possible that these species are older than M. tuberculosis, we postulated that the DR locus was acquired by the M. tuberculosis complex species or by an ancestor bacterium.

Angel Cataldi

2004-01-01

314

Essential Bacillus subtilis genes  

Science.gov (United States)

To estimate the minimal gene set required to sustain bacterial life in nutritious conditions, we carried out a systematic inactivation of Bacillus subtilis genes. Among ?4,100 genes of the organism, only 192 were shown to be indispensable by this or previous work. Another 79 genes were predicted to be essential. The vast majority of essential genes were categorized in relatively few domains of cell metabolism, with about half involved in information processing, one-fifth involved in the synthesis of cell envelope and the determination of cell shape and division, and one-tenth related to cell energetics. Only 4% of essential genes encode unknown functions. Most essential genes are present throughout a wide range of Bacteria, and almost 70% can also be found in Archaea and Eucarya. However, essential genes related to cell envelope, shape, division, and respiration tend to be lost from bacteria with small genomes. Unexpectedly, most genes involved in the Embden–Meyerhof–Parnas pathway are essential. Identification of unknown and unexpected essential genes opens research avenues to better understanding of processes that sustain bacterial life. PMID:12682299

Kobayashi, K.; Ehrlich, S. D.; Albertini, A.; Amati, G.; Andersen, K. K.; Arnaud, M.; Asai, K.; Ashikaga, S.; Aymerich, S.; Bessieres, P.; Boland, F.; Brignell, S. C.; Bron, S.; Bunai, K.; Chapuis, J.; Christiansen, L. C.; Danchin, A.; Debarbouille, M.; Dervyn, E.; Deuerling, E.; Devine, K.; Devine, S. K.; Dreesen, O.; Errington, J.; Fillinger, S.; Foster, S. J.; Fujita, Y.; Galizzi, A.; Gardan, R.; Eschevins, C.; Fukushima, T.; Haga, K.; Harwood, C. R.; Hecker, M.; Hosoya, D.; Hullo, M. F.; Kakeshita, H.; Karamata, D.; Kasahara, Y.; Kawamura, F.; Koga, K.; Koski, P.; Kuwana, R.; Imamura, D.; Ishimaru, M.; Ishikawa, S.; Ishio, I.; Le Coq, D.; Masson, A.; Mauel, C.; Meima, R.; Mellado, R. P.; Moir, A.; Moriya, S.; Nagakawa, E.; Nanamiya, H.; Nakai, S.; Nygaard, P.; Ogura, M.; Ohanan, T.; O'Reilly, M.; O'Rourke, M.; Pragai, Z.; Pooley, H. M.; Rapoport, G.; Rawlins, J. P.; Rivas, L. A.; Rivolta, C.; Sadaie, A.; Sadaie, Y.; Sarvas, M.; Sato, T.; Saxild, H. H.; Scanlan, E.; Schumann, W.; Seegers, J. F. M. L.; Sekiguchi, J.; Sekowska, A.; Seror, S. J.; Simon, M.; Stragier, P.; Studer, R.; Takamatsu, H.; Tanaka, T.; Takeuchi, M.; Thomaides, H. B.; Vagner, V.; van Dijl, J. M.; Watabe, K.; Wipat, A.; Yamamoto, H.; Yamamoto, M.; Yamamoto, Y.; Yamane, K.; Yata, K.; Yoshida, K.; Yoshikawa, H.; Zuber, U.; Ogasawara, N.

2003-01-01

315

DNA, Genes and Chromosomes  

Science.gov (United States)

Today you will learn about the parts of DNA and what DNA, genes and chromosomes are. Today you will learn what DNA, genes and chromosomes are and the parts of the DNA molecule. Look at all of the websites, take whatever notes you need to. At the end of the assignment, be able to describle DNA, the parts of DNA, genes and chromosomes. Covers Biology Core Curriculum, ...

Fomby, Mrs.

2007-11-07

316

Genes, dreams, and cancer.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

There have been tremendous advances in our understanding of cancer from the application of molecular biology over the past decade. The disease is caused by a series of defects in the genes that accelerate growth--oncogenes--and those that slow down cellular turnover--tumour suppressor genes. The proteins they encode provide a promising hunting ground in which to design and test new anticancer drugs. Several treatment strategies are now under clinical trial entailing direct gene transfer. Thes...

Sikora, K.

1994-01-01

317

Gene and genome duplication.  

Science.gov (United States)

Genomic sequencing projects have revealed the productivity of processes duplicating genes or entire chromosome segments. Substantial proportions of the yeast, Arabidopsis and human gene complements are made up of duplicates. This has prompted much interest in the processes of duplication, functional divergence and loss of genes, has renewed the debate on whether an early vertebrate genome was tetraploid, and has inspired mathematical models and algorithms in computational biology. PMID:11682313

Sankoff, D

2001-12-01

318

Mycobacterium shinjukuense sp. nov., a slowly growing, non-chromogenic species isolated from human clinical specimens.  

Science.gov (United States)

Seven isolates of a slowly growing, non-chromogenic Mycobacterium species were obtained from sputum and bronchial lavage fluid samples from elderly patients in different regions of Japan. These isolates were distinguished from related non-tuberculous species by colony morphology, positive results for Tween hydrolysis, catalase at 68 °C, nitrate reductase and pyrazinamidase and negative results for semi-quantitative catalase, urease and arylsulfatase. The mycolic acid pattern obtained by HPLC revealed a single cluster of late-eluting mycolic acids similar to but different from those of Mycobacterium malmoense ATCC 29571(T). The 16S rRNA gene, 16S-23S internal transcribed spacer (ITS), rpoB and hsp65 sequences were unique in comparison with those of other mycobacteria. Comparison of 16S rRNA gene sequences showed that the isolates were most closely related to Mycobacterium tuberculosis H37Rv(T) (21 base differences in 1508 bp; 98.6 % 16S rRNA gene sequence similarity). A representative strain, GTC 2738(T), showed 91.9 % rpoB sequence similarity with Mycobacterium marinum strain M, 95 % hsp65 sequence similarity with Mycobacterium kansasii CIP 104589(T) and 81.1 % 16S-23S ITS sequence similarity with Mycobacterium gordonae ATCC 14470(T). Phylogenetic analysis of concatenated sequences of the 16S rRNA, rpoB and hsp65 genes showed that strain GTC 2738(T) was located on a distinct clade adjacent to M. tuberculosis, M. ulcerans and M. marinum, with bootstrap values of 81 %. DNA-DNA hybridization demonstrated less than 70 % reassociation with type strains of genetically related species and supported the novel species status of the isolates. On the basis of this evidence, a novel species with the name Mycobacterium shinjukuense sp. nov. is proposed. The type strain, isolated from a sputum sample, is strain GTC 2738(T)(?= JCM 14233(T)?= CCUG 53584(T)). PMID:20833878

Saito, Hajime; Iwamoto, Tomotada; Ohkusu, Kiyofumi; Otsuka, Yoshihito; Akiyama, Yasushi; Sato, Shigeki; Taguchi, Osamu; Sueyasu, Yoshiko; Kawabe, Yoshiko; Fujimoto, Hisao; Ezaki, Takayuki; Butler, Ray

2011-08-01

319

Gene Conversion and Evolution of Gene Families: An Overview  

Directory of Open Access Journals (Sweden)

Full Text Available The importance of gene conversion for the evolution of gene families is reviewed. Four problems concerning gene conversion, i.e., concerted evolution, generation of useful variation, deleterious effects, and relation to neofunctionalization, are discussed by surveying reported examples of evolving gene families. Emphasis is given toward understanding interactive effects of gene conversion and natural selection.

Tomoko Ohta

2010-09-01

320

Evaluation of GeneXpert MTB/RIF for diagnosis of tuberculous meningitis.  

Science.gov (United States)

Tuberculous meningitis (TBM) is the most severe form of tuberculosis. Microbiological confirmation is rare, and treatment is often delayed, increasing mortality and morbidity. The GeneXpert MTB/RIF test was evaluated in a large cohort of patients with suspected tuberculous meningitis. Three hundred seventy-nine patients presenting with suspected tuberculous meningitis to the Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam, between 17 April 2011 and 31 December 2012 were included in the study. Cerebrospinal fluid samples were tested by Ziehl-Neelsen smear, mycobacterial growth indicator tube (MGIT) culture, and Xpert MTB/RIF. Rifampin (RIF) resistance results by Xpert were confirmed by an MTBDR-Plus line probe assay and all positive cultures were tested by phenotypic MGIT drug susceptibility testing. Overall, 182/379 included patients (48.0%) were diagnosed with tuberculous meningitis. Sensitivities of Xpert, smear, and MGIT culture among patients diagnosed with TBM were 59.3% (108/182 [95% confidence interval {CI}, 51.8 to 66.5%]), 78.6% (143/182 [95% CI, 71.9 to 84.3%]) and 66.5% (121/182 [95% CI, 59.1 to 73.3%]), respectively. There was one false-positive Xpert MTB/RIF test (99.5% specificity). Four cases of RIF resistance (4/109; 3.7%) were identified by Xpert, of which 3 were confirmed to be multidrug-resistant (MDR) TBM and one was culture negative. Xpert MTB/RIF is a rapid and specific test for the diagnosis of tuberculous meningitis. The addition of a vortexing step to sample processing increased sensitivity for confirmed TBM by 20% (P = 0.04). Meticulous examination of a smear from a large volume of cerebrospinal fluid (CSF) remains the most sensitive technique but is not practical in most laboratories. The Xpert MTB/RIF represents a significant advance in the early diagnosis of this devastating condition. PMID:24197880

Nhu, Nguyen Thi Quynh; Heemskerk, Dorothee; Thu, Do Dang Anh; Chau, Tran Thi Hong; Mai, Nguyen Thi Hoang; Nghia, Ho Dang Trung; Loc, Pham Phu; Ha, Dang Thi Minh; Merson, Laura; Thinh, Tran Thi Van; Day, Jeremy; Chau, Nguyen van Vinh; Wolbers, Marcel; Farrar, Jeremy; Caws, Maxine

2014-01-01

 
 
 
 
321

The effect of MSMEG_6402 gene disruption on the cell wall structure of Mycobacterium smegmatis.  

Science.gov (United States)

Arabinogalactan (AG) of mycobacterial cell wall consists of arabinan region, galactan region and disaccharide linker. The arabinan is composed of D-arabinofuranose residues, and decaprenyphosphoryl-D-arabinose (DPA) is the donor of the D-arabinofuranose residues. DPA is formed from phosphoribose diphosphate (PRPP) in a four-step process catalyzed by transferase, phosphatase and epimerase, respectively. Mycobacterium tuberculosis Rv3806c has been identified as PRPP: decaprenyl-phosphate 5-phosphoribosyltransferase, and heteromeric Rv3790/Rv3791 has epimerase activity. Rv3807c is putative phospholipid phosphatase. However, there is no direct biochemical evidence since expression of Rv3807c has been unsuccessful. Mycobacterium smegmatis MSMEG_6402 is ortholog of Rv3807c. To investigate the function of MSMEG_6402 on AG biosynthesis, a conditional MSMEG_6402 gene knock out (M. sm-?M_6402) strain was constructed through homologous recombination technique. The morphological and compositional changes of cell wall were examined in the M. sm-?M_6402 strain. The M. sm-?M_6402 strain grew at non-permissive temperature slower than that at permissive temperature, indicating that MSMEG_6402 is non-essential for growth of M. smegmatis. The change of cell shape and detectable bulging on the cell surface of M. sm-?M_6402 strain were observed by scanning electron microscopy, and curled as well as deformed cell wall of M. sm-?M_6402 strain was revealed by transmission electron microscopy. Analysis of sugar composition in the cell wall by HPLC indicated that the ratio of arabinofuran to galactofuran in M. sm-?M_6402 strain was changed to 1.7:1 comparing with 2:1 in the wild type. It demonstrates that the lacking MSMEG_6402 interferes the biosynthesis of arabinan. Analyzing 5' P-DPR and DPR from both M. sm-?M_6402 strain and wild type M. smegmatis is undergoing in this lab. PMID:21575707

Jiang, Tao; He, Lianqi; Zhan, Yaoyao; Zang, Shizhu; Ma, Yufang; Zhao, Xiaojiao; Zhang, Cuili; Xin, Yi

2011-09-01

322

Integron associated mobile genes  

Science.gov (United States)

Lateral gene transfer (LGT) impacts on the evolution of prokaryotes in both the short and long-term. The short-term impacts of mobilized genes are a concern to humans since LGT explains the global rise of multi drug resistant pathogens seen in the past 70 years. However, LGT has been a feature of prokaryotes from the earliest days of their existence and the concept of a bifurcating tree of life is not entirely applicable to prokaryotes since most genes in extant prokaryotic genomes have probably been acquired from other lineages. Successful transfer and maintenance of a gene in a new host is understandable if it acts independently of cell networks and confers an advantage. Antibiotic resistance provides an example of this whereby a gene can be advantageous in virtually any cell across broad species backgrounds. In a longer evolutionary context however laterally transferred genes can be assimilated into even essential cell networks. How this happens is not well understood and we discuss recent work that identifies a mobile gene, unique to a cell lineage, which is detrimental to the cell when lost. We also present some additional data and believe our emerging model will be helpful in understanding how mobile genes integrate into cell networks. PMID:22754748

Labbate, Maurizio; Boucher, Yan; Luu, Ivan; Chowdhury, Piklu Roy; Stokes, H.W.

2012-01-01

323

Gene : CBRC-MMUR-01-1271 [SEVENS  

Full Text Available CBRC-MMUR-01-1271 Novel UN B UNKNOWN SRGEF_MOUSE 1.1 34% ref|YP_639653.1| precorrin-3B synthase ... [Mycobacterium sp. MCS ] ref|YP_938521.1| precorrin-3B synthase [Mycobacte ... G08597.1| Precorrin-3B synthase [Mycobacterium sp. MCS ] gb|ABL91731.1| precorrin-3B synthase [Mycobacteri ...

324

Common fragile genes  

Directory of Open Access Journals (Sweden)

Full Text Available Common chromosome fragile sites show susceptibility to DNA damage, leading to alterations that contribute to cancer development. The cloning and characterization of fragile sites have demonstrated that fragile sites are associated with genes that relate to tumorigenesis. Identification of the basis of instability at fragile sites and the related genes provides an entree to understanding of important aspects of chromosomal instability, a prominent feature of neoplastic genomes. FHIT/FRA3B and WWOX/FRA16D, the most sensitive common fragile genes in the human genome, function as tumor suppressor genes. The common features of these two common fragile genes are summarized, and suggest clues to understanding the relation between genomic instability and tumor biology.

K Huebner

2004-03-01

325

GeneCards Version 3: the human gene integrator  

Digital Repository Infrastructure Vision for European Research (DRIVER)

GeneCards (www.genecards.org) is a comprehensive, authoritative compendium of annotative information about human genes, widely used for nearly 15 years. Its gene-centric content is automatically mined and integrated from over 80 digital sources, resulting in a web-based deep-linked card for each of >73 000 human gene entries, encompassing the following categories: protein coding, pseudogene, RNA gene, genetic locus, cluster and uncategorized. We now introduce GeneCards Version 3, featuring a ...

Safran, Marilyn; Dalah, Irina; Alexander, Justin; Rosen, Naomi; Iny Stein, Tsippi; Shmoish, Michael; Nativ, Noam; Bahir, Iris; Doniger, Tirza; Krug, Hagit; Sirota-madi, Alexandra; Olender, Tsviya; Golan, Yaron; Stelzer, Gil; Harel, Arye

2010-01-01

326

Cloning Human Chromosome 17 Genes:.  

Science.gov (United States)

Our research interest is focused on the development of new strategies to identify genes from chromosome 17. The isolation of genes transcribed from chromosome 17 will provide candidates for the proposed sporadic breast and ovarian cancer genes. We have re...

C. C. Lee

1995-01-01

327

Genome-wide transcriptional profiling of peripheral blood leukocytes from cattle infected with Mycobacterium bovis reveals suppression of host immune genes  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Mycobacterium bovis is the causative agent of bovine tuberculosis (BTB, a pathological infection with significant economic impact. Recent studies have highlighted the role of functional genomics to better understand the molecular mechanisms governing the host immune response to M. bovis infection. Furthermore, these studies may enable the identification of novel transcriptional markers of BTB that can augment current diagnostic tests and surveillance programmes. In the present study, we have analysed the transcriptome of peripheral blood leukocytes (PBL from eight M. bovis-infected and eight control non-infected age-matched and sex-matched Holstein-Friesian cattle using the Affymetrix® GeneChip® Bovine Genome Array with 24,072 gene probe sets representing more than 23,000 gene transcripts. Results Control and infected animals had similar mean white blood cell counts. However, the mean number of lymphocytes was significantly increased in the infected group relative to the control group (P = 0.001, while the mean number of monocytes was significantly decreased in the BTB group (P = 0.002. Hierarchical clustering analysis using gene expression data from all 5,388 detectable mRNA transcripts unambiguously partitioned the animals according to their disease status. In total, 2,960 gene transcripts were differentially expressed (DE between the infected and control animal groups (adjusted P-value threshold ? 0.05; with the number of gene transcripts showing decreased relative expression (1,563 exceeding those displaying increased relative expression (1,397. Systems analysis using the Ingenuity® Systems Pathway Analysis (IPA Knowledge Base revealed an over-representation of DE genes involved in the immune response functional category. More specifically, 64.5% of genes in the affects immune response subcategory displayed decreased relative expression levels in the infected animals compared to the control group. Conclusions This study demonstrates that genome-wide transcriptional profiling of PBL can distinguish active M. bovis-infected animals from control non-infected animals. Furthermore, the results obtained support previous investigations demonstrating that mycobacterial infection is associated with host transcriptional suppression. These data support the use of transcriptomic technologies to enable the identification of robust, reliable transcriptional markers of active M. bovis infection.

Killick Kate E

2011-12-01

328

Some Genes Are Dominant  

Science.gov (United States)

This interactive activity, adapted from the Dolan DNA Learning Center, illustrates how Gregor Mendel used pure-bred yellow and green peas to show that some genes are dominant and others are recessive.

Foundation, Wgbh E.

2007-04-19

329

The fragmented gene.  

Science.gov (United States)

While once almost synonymous, there is an increasing gap between the expanding definition of what constitutes a gene and the conservative and narrowly defined terms code or coding, which for a long time, almost exclusively constituted the open reading frame. Much confusion results from this disparity, especially in light of the plethora of noncoding RNAs (more correctly termed "non-protein-coding RNAs") that usually are encoded and transcribed by their own genes. A simple solution would be to adopt Ed Trifonov's less constrained definition of a code as any sequence pattern that can have a biological function. Such consideration favors not only a more complex view of the gene as an entity composed of many more or less conserved subgenic modules, but also a concept of modular evolution of genes and entire genomes. PMID:19845638

Brosius, Jürgen

2009-10-01

330

Genes underlying altruism.  

Science.gov (United States)

William D. Hamilton postulated the existence of 'genes underlying altruism', under the rubric of inclusive fitness theory, a half-century ago. Such genes are now poised for discovery. In this article, we develop a set of intuitive criteria for the recognition and analysis of genes for altruism and describe the first candidate genes affecting altruism from social insects and humans. We also provide evidence from a human population for genetically based trade-offs, underlain by oxytocin-system polymorphisms, between alleles for altruism and alleles for non-social cognition. Such trade-offs between self-oriented and altruistic behaviour may influence the evolution of phenotypic diversity across all social animals. PMID:24132092

Thompson, Graham J; Hurd, Peter L; Crespi, Bernard J

2013-01-01

331

Mycobacterium pseudoshottsii sp. nov., a slowly growing chromogenic species isolated from Chesapeake Bay striped bass (Morone saxatilis)  

Science.gov (United States)

A group of slowly growing photochromogenic mycobacteria was isolated from Chesapeake Bay striped bass (Morone saxatilis) during an epizootic of mycobacteriosis. Growth characteristics, acid-fastness and 16S rRNA gene sequencing results were consistent with those of the genus Mycobacterium. Biochemical reactions, growth characteristics and mycolic acid profiles (HPLC) resembled those of Mycobacterium shottsii, a non-pigmented mycobacterium also isolated during the same epizootic. Sequencing of the 16S rRNA genes, the gene encoding the exported repeated protein (erp) and the gene encoding the 65 kDa heat-shock protein (hsp65) and restriction enzyme analysis of the hsp65 gene demonstrated that this group of isolates is unique. Insertion sequences associated with Mycobacterium ulcerans, IS2404 and IS2606, were detected by PCR. These isolates could be differentiated from other slowly growing pigmented mycobacteria by their inability to grow at 37 ??C, production of niacin and urease, absence of nitrate reductase, negative Tween 80 hydrolysis and resistance to isoniazid (1 ??g ml-1), p-nitrobenzoic acid, thiacetazone and thiophene-2-carboxylic hydrazide. On the basis of this polyphasic study, it is proposed that these isolates represent a novel species, Mycobacterium pseudoshottsii sp. nov. The type strain, L15T, has been deposited in the American Type Culture Collection as ATCC BAA-883T and the National Collection of Type Cultures (UK) as NCTC 13318T. ?? 2005 IUMS.

Rhodes, M. W.; Kator, H.; McNabb, A.; Deshayes, C.; Reyrat, J. -M.; Brown-Elliott, B. A.; Wallace, Jr. , R.; Trott, K. A.; Parker, J. M.; Lifland, B.; Osterhout, G.; Kaattari, I.; Reece, K.; Vogelbein, W.; Ottinger, C. A.

2005-01-01

332

Gene delivery to cornea  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper reviews the strategies of in vivo gene delivery to the cornea. A number of studies have demonstrated the feasibility of targeted delivery of oligonucleotides, small interfering RNA (siRNA), plasmid DNA, and viral vectors to the corneal cells in vivo, specifically stromal keratocytes and corneal epithelial cells, via intrastromal injection, iontophoresis, electroporation, and gene gun. Intrastromal injection of plasmid DNA and adenovirus each can result in efficient transgene expres...

Hao, Jinsong; Li, S. Kevin; Kao, Winston W. Y.; Liu, Chia-yang

2010-01-01

333

Epidemic of Postsurgical Infections Caused by Mycobacterium massiliense?  

Science.gov (United States)

An epidemic of infections after video-assisted surgery (1,051 possible cases) caused by rapidly growing mycobacteria (RGM) and involving 63 hospitals in the state of Rio de Janeiro, Brazil, occurred between August 2006 and July 2007. One hundred ninety-seven cases were confirmed by positive acid-fast staining and/or culture techniques. Thirty-eight hospitals had cases confirmed by mycobacterial culture, with a total of 148 available isolates recovered from 146 patients. Most (n = 144; 97.2%) isolates presented a PRA-hsp65 restriction pattern suggestive of Mycobacterium bolletii or Mycobacterium massiliense. Seventy-four of these isolates were further identified by hsp65 or rpoB partial sequencing, confirming the species identification as M. massiliense. Epidemic isolates showed susceptibility to amikacin (MIC at which 90% of the tested isolates are inhibited [MIC90], 8 ?g/ml) and clarithromycin (MIC90, 0.25 ?g/ml) but resistance to ciprofloxacin (MIC90, ?32 ?g/ml), cefoxitin (MIC90, 128 ?g/ml), and doxycycline (MIC90, ?64 ?g/ml). Representative epidemic M. massiliense isolates that were randomly selected, including at least one isolate from each hospital where confirmed cases were detected, belonged to a single clone, as indicated by the analysis of pulsed-field gel electrophoresis (PFGE) patterns. They also had the same PFGE pattern as that previously observed in two outbreaks that occurred in other Brazilian cities; we designated this clone BRA100. All five BRA100 M. massiliense isolates tested presented consistent tolerance to 2% glutaraldehyde. This is the largest epidemic of postsurgical infections caused by RGM reported in the literature to date in Brazil. PMID:19403765

Duarte, Rafael Silva; Lourenco, Maria Cristina Silva; Fonseca, Leila de Souza; Leao, Sylvia Cardoso; Amorim, Efigenia de Lourdes T.; Rocha, Ingrid L. L.; Coelho, Fabrice Santana; Viana-Niero, Cristina; Gomes, Karen Machado; da Silva, Marlei Gomes; de Oliveira Lorena, Nadia Suely; Pitombo, Marcos Bettini; Ferreira, Rosa M. C.; de Oliveira Garcia, Marcio Henrique; de Oliveira, Gisele Pinto; Lupi, Otilia; Vilaca, Bruno Rios; Serradas, Lucia Rodrigues; Chebabo, Alberto; Marques, Elizabeth Andrade; Teixeira, Lucia Martins; Dalcolmo, Margareth; Senna, Simone Goncalves; Sampaio, Jorge Luiz Mello

2009-01-01

334

Development of a quantitative analysis method for mRNA from Mycobacterium leprae and slow-growing acid-fast bacteria  

Energy Technology Data Exchange (ETDEWEB)

This study aimed to develop a specific method for detection and quantitative determination of mRNA that allows estimation of viable counts of M. leprae and other mycobacteria. Of heart-shock protein of 65 kDa (hsp65), mRNA was used as an indicator to discriminate the living cells and died ones. To compare mRNA detections by RNase protection assay (RPA) and Northern blot hybridization (NBH), labelled anti-sense RNA for hsp65 gene of M. leprae was synthesized using plasmid pUC8/N5. The anti-sense RNA synthesized from the template DNA containing about 580 bp (194 to 762) of hsp65 gene. When compared with NBH method, the amount of probe required for the detection by RPA method was 1/30 or less and the detection sensitivity of RPA was also 10 times higher. In addition, complicated procedures were needed to eliminate non-specific reactions in NBH method. These results indicated that RPA method is more convenient and superior for the mRNA detection. However, isotope degradation in the probe used for RPA method might affect the results. Therefore, {sup 33}P of {sup 35}P, of which degradation energy is less that {sup 32}P should be used for labelling. Total RNA was effectively extracted from M. chelonae, M. marinum by AGPC method, but not from M. leprae. In conclusion, RPA is a very effective detection method for these mRNA, but it seems necessary to further improve the sensitivity of detection for a small amount of test materials. (M.N.)

Nakanaga, Kazue; Maeda Shinji; Matsuoka, Masanori; Kashiwabara, Yoshiko [National Inst. of Infectious Diseases, Tokyo (Japan)

1999-02-01

335

Development of a quantitative analysis method for mRNA from Mycobacterium leprae and slow-growing acid-fast bacteria  

International Nuclear Information System (INIS)

This study aimed to develop a specific method for detection and quantitative determination of mRNA that allows estimation of viable counts of M. leprae and other mycobacteria. Of heart-shock protein of 65 kDa (hsp65), mRNA was used as an indicator to discriminate the living cells and died ones. To compare mRNA detections by RNase protection assay (RPA) and Northern blot hybridization (NBH), labelled anti-sense RNA for hsp65 gene of M. leprae was synthesized using plasmid pUC8/N5. The anti-sense RNA synthesized from the template DNA containing about 580 bp (194 to 762) of hsp65 gene. When compared with NBH method, the amount of probe required for the detection by RPA method was 1/30 or less and the detection sensitivity of RPA was also 10 times higher. In addition, complicated procedures were needed to eliminate non-specific reactions in NBH method. These results indicated that RPA method is more convenient and superior for the mRNA detection. However, isotope degradation in the probe used for RPA method might affect the results. Therefore, 33P of 35P, of which degradation energy is less that 32P should be used for labelling. Total RNA was effectively extracted from M. chelonae, M. marinum by AGPC method, but not from M. leprae. In conclusion, RPA is a very effective detection method for these mRNA, but it seems necessary to further improve the sensitivity of detection for a small amount of test materials. (M.N.) materials. (M.N.)

336

Neuronal cell adhesion genes  

Science.gov (United States)

The major mental disorders, schizophrenia and bipolar disorder, are substantially heritable. Recent genomic studies have identified a small number of common and rare risk genes contributing to both disorders and support epidemiological evidence that genetic susceptibility overlaps between them. Prompted by the question of whether risk genes cluster in specific molecular pathways or implicate discrete mechanisms, we and others have developed hypothesis-free methods of investigating genome-wide association datasets at a pathway-level. The application of our method to the 212 experimentally-derived pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database identified significant association between the cell adhesion molecule (CAM) pathway and both schizophrenia and bipolar disorder susceptibility across three GWAS datasets. Interestingly, a similar approach applied to an autistic spectrum disorders (ASDs) sample identified a similar pathway and involved many of the same genes. Disruption of a number of these genes (including NRXN1, CNTNAP2 and CASK) are known to cause diverse neurodevelopmental brain disorder phenotypes including schizophenia, autism, learning disability and specific language disorder. Taken together these studies bring the CAM pathway sharply into focus for more comprehensive DNA sequencing to identify the critical genes, and investigate their relationships and interaction with environmental risk factors in the expression of many seemingly different neurodevelopmental disorders. PMID:20574149

2010-01-01

337

Evidence for homosexuality gene  

Energy Technology Data Exchange (ETDEWEB)

A genetic analysis of 40 pairs of homosexual brothers has uncovered a region on the X chromosome that appears to contain a gene or genes for homosexuality. When analyzing the pedigrees of homosexual males, the researcheres found evidence that the trait has a higher likelihood of being passed through maternal genes. This led them to search the X chromosome for genes predisposing to homosexuality. The researchers examined the X chromosomes of pairs of homosexual brothers for regions of DNA that most or all had in common. Of the 40 sets of brothers, 33 shared a set of five markers in the q28 region of the long arm of the X chromosome. The linkage has a LOD score of 4.0, which translates into a 99.5% certainty that there is a gene or genes in this area that predispose males to homosexuality. The chief researcher warns, however, that this one site cannot explain all instances of homosexuality, since there were some cases where the trait seemed to be passed paternally. And even among those brothers where there was no evidence that the trait was passed paternally, seven sets of brothers did not share the Xq28 markers. It seems likely that homosexuality arises from a variety of causes.

Pool, R.

1993-07-16

338

Stochastic Gene Expression Model Base Gene Regulatory Networks  

Science.gov (United States)

Gene regulatory networks consist of a number of genes and their interactions which regulate expressions of the genes. Along with the development of gene regulatory network studies, computer simulations have become a valuable tool to evaluate complex relationships between genes. Due to the stochastic nature of gene expressions, various stochastic approaches have attracted increasing interest. In this study, we build gene regulatory networks based on a stochastic gene expression model with delicate assumptions such as transcription, translation, DNA-protein, protein-protein associations and time delay for protein activation. Two simple in-silico gene regulatory network models are constructed and monitored their expression profiles reflecting the inhibition and activation of the gene regulations.

Kim, Haseong; Gelenbe, Erol

339

Gene set analysis for longitudinal gene expression data  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Gene set analysis (GSA) has become a successful tool to interpret gene expression profiles in terms of biological functions, molecular pathways, or genomic locations. GSA performs statistical tests for independent microarray samples at the level of gene sets rather than individual genes. Nowadays, an increasing number of microarray studies are conducted to explore the dynamic changes of gene expression in a variety of species and biological scenarios. In t...

Piepho Hans-Peter; Harrar Solomon W; Bathke Arne C; Wang Haiyan; Zhang Ke; Deng Youping

2011-01-01

340

GeneCards Version 3: the human gene integrator.  

Science.gov (United States)

GeneCards (www.genecards.org) is a comprehensive, authoritative compendium of annotative information about human genes, widely used for nearly 15 years. Its gene-centric content is automatically mined and integrated from over 80 digital sources, resulting in a web-based deep-linked card for each of >73,000 human gene entries, encompassing the following categories: protein coding, pseudogene, RNA gene, genetic locus, cluster and uncategorized. We now introduce GeneCards Version 3, featuring a speedy and sophisticated search engine and a revamped, technologically enabling infrastructure, catering to the expanding needs of biomedical researchers. A key focus is on gene-set analyses, which leverage GeneCards' unique wealth of combinatorial annotations. These include the GeneALaCart batch query facility, which tabulates user-selected annotations for multiple genes and GeneDecks, which identifies similar genes with shared annotations, and finds set-shared annotations by descriptor enrichment analysis. Such set-centric features address a host of applications, including microarray data analysis, cross-database annotation mapping and gene-disorder associations for drug targeting. We highlight the new Version 3 database architecture, its multi-faceted search engine, and its semi-automated quality assurance system. Data enhancements include an expanded visualization of gene expression patterns in normal and cancer tissues, an integrated alternative splicing pattern display, and augmented multi-source SNPs and pathways sections. GeneCards now provides direct links to gene-related research reagents such as antibodies, recombinant proteins, DNA clones and inhibitory RNAs and features gene-related drugs and compounds lists. We also portray the GeneCards Inferred Functionality Score annotation landscape tool for scoring a gene's functional information status. Finally, we delineate examples of applications and collaborations that have benefited from the GeneCards suite. Database URL: www.genecards.org. PMID:20689021

Safran, Marilyn; Dalah, Irina; Alexander, Justin; Rosen, Naomi; Iny Stein, Tsippi; Shmoish, Michael; Nativ, Noam; Bahir, Iris; Doniger, Tirza; Krug, Hagit; Sirota-Madi, Alexandra; Olender, Tsviya; Golan, Yaron; Stelzer, Gil; Harel, Arye; Lancet, Doron

2010-01-01

 
 
 
 
341

Radionuclide reporter gene imaging for cardiac gene therapy  

International Nuclear Information System (INIS)

In the field of cardiac gene therapy, angiogenic gene therapy has been most extensively investigated. The first clinical trial of cardiac angiogenic gene therapy was reported in 1998, and at the peak, more than 20 clinical trial protocols were under evaluation. However, most trials have ceased owing to the lack of decisive proof of therapeutic effects and the potential risks of viral vectors. In order to further advance cardiac angiogenic gene therapy, remaining open issues need to be resolved: there needs to be improvement of gene transfer methods, regulation of gene expression, development of much safer vectors and optimisation of therapeutic genes. For these purposes, imaging of gene expression in living organisms is of great importance. In radionuclide reporter gene imaging, ''reporter genes'' transferred into cell nuclei encode for a protein that retains a complementary ''reporter probe'' of a positron or single-photon emitter; thus expression of the reporter genes can be imaged with positron emission tomography or single-photon emission computed tomography. Accordingly, in the setting of gene therapy, the location, magnitude and duration of the therapeutic gene co-expression with the reporter genes can be monitored non-invasively. In the near future, gene therapy may evolve into combination therapy with stem/progenitor cell transplantation, so-called cell-based gene therapy or gene-modified cell therapy. Radionuclide reporter gene imaging is now expected to contribute in providing evidence on the usefulness of this novel therapeutic approach, as well as in investigating the molecular mechanisms underlying neovascularisation and safety issues relevant to further progress in conventional gene therapy. (orig.)

342

Radionuclide reporter gene imaging for cardiac gene therapy  

Energy Technology Data Exchange (ETDEWEB)

In the field of cardiac gene therapy, angiogenic gene therapy has been most extensively investigated. The first clinical trial of cardiac angiogenic gene therapy was reported in 1998, and at the peak, more than 20 clinical trial protocols were under evaluation. However, most trials have ceased owing to the lack of decisive proof of therapeutic effects and the potential risks of viral vectors. In order to further advance cardiac angiogenic gene therapy, remaining open issues need to be resolved: there needs to be improvement of gene transfer methods, regulation of gene expression, development of much safer vectors and optimisation of therapeutic genes. For these purposes, imaging of gene expression in living organisms is of great importance. In radionuclide reporter gene imaging, ''reporter genes'' transferred into cell nuclei encode for a protein that retains a complementary ''reporter probe'' of a positron or single-photon emitter; thus expression of the reporter genes can be imaged with positron emission tomography or single-photon emission computed tomography. Accordingly, in the setting of gene therapy, the location, magnitude and duration of the therapeutic gene co-expression with the reporter genes can be monitored non-invasively. In the near future, gene therapy may evolve into combination therapy with stem/progenitor cell transplantation, so-called cell-based gene therapy or gene-modified cell therapy. Radionuclide reporter gene imaging is now expected to contribute in providing evidence on the usefulness of this novel therapeutic approach, as well as in investigating the molecular mechanisms underlying neovascularisation and safety issues relevant to further progress in conventional gene therapy. (orig.)

Inubushi, Masayuki [Hokkaido University Graduate School of Medicine, Department of Molecular Imaging, Sapporo (Japan); Tamaki, Nagara [Hokkaido University Graduate School of Medicine, Department of Nuclear Medicine, Sapporo (Japan)

2007-06-15

343

FunGene: the Functional Gene Pipeline and Repository  

Directory of Open Access Journals (Sweden)

Full Text Available Ribosomal RNA genes have become the standard molecular markers for microbial community analysis for good reasons, including universal occurrence in cellular organisms, availability of large databases, and ease of rRNA gene region amplification and analysis. As markers, however, rRNA genes have some significant limitations. The rRNA genes are often present in multiple copies, unlike most protein-coding genes. The slow rate of change in rRNA genes means that multiple species sometimes share identical 16S rRNA gene sequences, while many more species share identical sequences in the short 16S rRNA regions commonly analyzed. In addition, the genes involved in many important processes are not distributed in a phylogenetically coherent manner, potentially due to gene loss or horizontal gene transfer. While rRNA genes remain the most commonly used markers, key genes in ecologically important pathways, e.g., those involved in carbon and nitrogen cycling, can provide important insights into community composition and function not obtainable through rRNA analysis. However, working with ecofunctional gene data requires some tools beyond those required for rRNA analysis. To address this, our Functional Gene Pipeline and Repository (FunGene; http://fungene.cme.msu.edu/ offers databases of many common ecofunctional genes and proteins, as well as integrated tools that allow researchers to browse these collections and choose subsets for further analysis, build phylogenetic trees, test primers and probes for coverage, and download aligned sequences. Additional FunGene tools are specialized to process coding gene amplicon data. For example, FrameBot produces frameshift-corrected protein and DNA sequences from raw reads while finding the most closely related protein reference sequence. These tools can help provide better insight into microbial communities by directly studying key genes involved in important ecological processes.

JamesR.Cole

2013-10-01

344

A Gene Score Test for Disease Association with Multiple Genes  

Directory of Open Access Journals (Sweden)

Full Text Available The traditional method for creating a gene score to predict a given outcome is to use the most statistically significant single nucleotide polymorphisms (SNPs from all SNPs which were tested. There are several disadvantages of this approach such as excluding SNPs that do not have strong single effects when tested on their own but do have strong joint effects when tested together with other SNPs. The interpretation of results from the traditional gene score may lack biological insight since the functional unit of interest is often the gene, not the single SNP. In this paper we present a new gene scoring method, which overcomes these problems as it generates a gene score for each gene, and the total gene score for all the genes available. First, we calculate a gene score for each gene and second, we test the association between this gene score and the outcome of interest (i.e. trait. Only the gene scores which are significantly associated with the outcome after multiple testing correction for the number of gene tests (not SNPs are considered in the total gene score calculation. This method controls false positive results caused by multiple tests within genes and between genes separately, and has the advantage of identifying multi-locus genetic effects, compared with the Bonferroni correction, false discovery rate (FDR, and permutation tests for all SNPs. Another main feature of this method is that we select the SNPs, which have different effects within a gene by using adjustment in multiple regressions and then combine the information from the selected SNPs within a gene to create a gene score. A simulation study has been conducted to evaluate finite sample performance of the proposed method.

Changchun Xie

2011-04-01

345

Advances in Gene Delivery Systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The transfer of genes into cells, both in vitro and in vivo, is critical for studying gene function and conducting gene therapy. Methods that utilize viral and nonviral vectors, as well as physical approaches, have been explored. Viral vector-mediated gene transfer employs replication-deficient viruses such as retro-virus, adenovirus, adeno-associated virus and herpes simplex virus. A major advantage of viral vectors is their high gene delivery efficiency. The nonviral vectors developed so fa...

Kamimura, Kenya; Suda, Takeshi; Zhang, Guisheng; Liu, Dexi

2011-01-01

346

Overview of gene structure.  

Science.gov (United States)

Throughout the C. elegans sequencing project Genefinder was the primary protein-coding gene prediction program. These initial predictions were manually reviewed by curators as part of a "first-pass annotation" and are actively curated by WormBase staff using a variety of data and information. In the WormBase data release WS133 there are 22,227 protein-coding gene, including 2,575 alternatively-spliced forms. Twenty-eight percent of these have every base of every exon confirmed by transcription evidence while an additional 51% have some bases confirmed. Most of the genes are relatively small covering a genomic region of about 3 kb. The average gene contains 6.4 coding exons accounting for about 26% of the genome. Most exons are small and separated by small introns. The median size of exons is 123 bases, while the most common size for introns is 47 bases. Protein-coding genes are denser on the autosomes than on chromosome X, and denser in the central region of the autosomes than on the arms. There are only 561 annotated pseudogenes but estimates but several estimates put this much higher. PMID:18023127

Spieth, John; Lawson, Daniel

2006-01-01

347

PNP anticancer gene therapy.  

Science.gov (United States)

Escherichia coli purine nucleoside phosphorylase (PNP) catalyzes the cleavage of 9-(2-deoxy-beta-D-ribofuranosyl)-6-methylpurine (MeP-dR), while human PNP does not. MeP-dR is well tolerated while the cleavage product, 6-methylpurine (MeP), is highly cytotoxic. This clinical profile suggests an anticancer gene therapy strategy in which solid tumors are transfected with the gene for E. coli PNP. Tumor cells expressing E. coli PNP will liberate MeP and be killed. Furthermore, MeP released from the cell via the purine transport system will enter nearby cells, resulting in bystander killing of tumor cells. To reduce toxicity resulting from activation of MeP-dR by intestinal tract flora, we redesigned the E. coli PNP active site to cleave prodrugs that are not cleaved by wild type E. coli PNP. It is possible that the variation of substrate specificity among enzymes that cleave nucleosides will have broader application in the gene therapy approach to prodrug activation. Here we review progress in the development of E. coli PNP anticancer gene therapy. We also review the structural basis for activity of nucleoside phosphorylases and suggest future directions for the development of activating enzymes for suicide gene therapy. PMID:16305530

Zhang, Yang; Parker, William B; Sorscher, Eric J; Ealick, Steven E

2005-01-01

348

Vertebrate gene predictions and the problem of large genes.  

DEFF Research Database (Denmark)

To find unknown protein-coding genes, annotation pipelines use a combination of ab initio gene prediction and similarity to experimentally confirmed genes or proteins. Here, we show that although the ab initio predictions have an intrinsically high false-positive rate, they also have a consistently low false-negative rate. The incorporation of similarity information is meant to reduce the false-positive rate, but in doing so it increases the false-negative rate. The crucial variable is gene size (including introns)--genes of the most extreme sizes, especially very large genes, are most likely to be incorrectly predicted. Udgivelsesdato: 2003-Sep

Wang, Jun; Li, ShengTing

2003-01-01

349

Norrie disease gene is distinct from the monoamine oxidase genes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The genes for MAO-A and MAO-B appear to be very close to the Norrie disease gene, on the basis of loss and /or disruption of the MAO genes and activities in atypical Norrie disease patients deleted for the DXS7 locus; linkage among the MAO genes, the Norrie disease gene, and the DXS7 locus; and mapping of all these loci to the chromosomal region Xp11. The present study provides evidence that the MAO genes are not disrupted in “classic” Norrie disease patients. Genomic DNA from these “no...

Sims, Katherine B.; Ozelius, Laurie; Corey, Timothy; Rinehart, William B.; Liberfarb, Ruth; Haines, Jonathan; Chen, Wei Jane; Norio, Reijo; Sankila, Eeva; La Chapelle, Albert; Murphy, Dennis L.; Gusella, James; Breakefield, Xandra O.

1989-01-01

350

MIR genes in Melanoma  

International Nuclear Information System (INIS)

On the basis of the previous project, further studies have been performed on the expression of selected miR genes in normal melanocytes and in melanoma cell lines, using real-time reverse transcription-PCR (qRT-PCR). In particular, we have analyzed the expression of 8 miR genes (i.e. 17-5p, 18a, 20a, 92a, 146a, 146b, 155, 221) in 10 different melanocyte cultures obtained from skin biopsies of 10 different healthy donors, and in 14 long-term human melanoma cell cultures

351

Quantifying gene expression.  

Science.gov (United States)

Identifying those genes that are expressed and at what levels is an essential part of almost any biological inquiry at the cellular level. Techniques such as Northern blot have been in existence for decades to perform this task, but advances in molecular biology and bioinstrumentation have led to the development of a variety of new techniques with a range of sensitivities, throughputs and quantitative capabilities. This review focuses on the latter issue. For several commonly used gene expression techniques, the extent and range of quantitative applicability are reviewed, and approaches for maximizing the accuracy and precision of these measurements are discussed. PMID:12074198

Roth, Charles M

2002-07-01

352

Gene Network Biological Validity Based on Gene-Gene Interaction Relevance  

Science.gov (United States)

In recent years, gene networks have become one of the most useful tools for modeling biological processes. Many inference gene network algorithms have been developed as techniques for extracting knowledge from gene expression data. Ensuring the reliability of the inferred gene relationships is a crucial task in any study in order to prove that the algorithms used are precise. Usually, this validation process can be carried out using prior biological knowledge. The metabolic pathways stored in KEGG are one of the most widely used knowledgeable sources for analyzing relationships between genes. This paper introduces a new methodology, GeneNetVal, to assess the biological validity of gene networks based on the relevance of the gene-gene interactions stored in KEGG metabolic pathways. Hence, a complete KEGG pathway conversion into a gene association network and a new matching distance based on gene-gene interaction relevance are proposed. The performance of GeneNetVal was established with three different experiments. Firstly, our proposal is tested in a comparative ROC analysis. Secondly, a randomness study is presented to show the behavior of GeneNetVal when the noise is increased in the input network. Finally, the ability of GeneNetVal to detect biological functionality of the network is shown.

Gomez-Vela, Francisco; Diaz-Diaz, Norberto

2014-01-01

353

Suicide genes or p53 gene and p53 target genes as targets for cancer gene therapy by ionizing radiation  

International Nuclear Information System (INIS)

Radiotherapy has some disadvantages due to the severe side-effect on the normal tissues at a curative dose of ionizing radiation (IR). Similarly, as a new developing approach, gene therapy also has some disadvantages, such as lack of specificity for tumors, limited expression of therapeutic gene, potential biological risk. To certain extent, above problems would be solved by the suicide genes or p53 gene and its target genes therapies targeted by ionizing radiation. This strategy not only makes up the disadvantage from radiotherapy or gene therapy alone, but also promotes success rate on the base of lower dose. By present, there have been several vectors measuring up to be reaching clinical trials. This review focused on the development of the cancer gene therapy through suicide genes or p53 and its target genes mediated by IR. (authors)

354

Identificação de micobactérias não tuberculosas isoladas de sítios estéreis em pacientes em um hospital universitário na cidade do Rio de Janeiro / Identification of nontuberculous mycobacteria isolated from clinical sterile sites in patients at a university hospital in the city of Rio de Janeiro, Brazil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Identificar micobactérias não tuberculosas (MNT) isoladas de sítios estéreis em pacientes internados no Hospital Universitário Clementino Fraga Filho, Rio de Janeiro (RJ) entre 2001 e 2006. MÉTODOS: Durante o período do estudo, 34 isolados de MNT de sítios estéreis de 14 pacientes, a maior [...] ia HIV positivos, foram submetidos a identificação fenotípica e hsp65 PCR-restriction enzyme analysis (PRA, análise por enzimas de restrição por PCR do gene hsp65). RESULTADOS: A maioria dos isolados foi identificada como Mycobacterium avium, seguida por M. monacense, M. kansasii e M. abscessus em menores proporções. CONCLUSÕES: A combinação de PRA, um método relativamente simples e de baixo custo, com algumas características fenotípicas pode fornecer a identificação correta de MNT na rotina de laboratórios clínicos. Abstract in english OBJECTIVE: To identify nontuberculous mycobacteria (NTM) isolated from sterile sites in patients hospitalized between 2001 and 2006 at the Clementino Fraga Filho University Hospital, located in the city of Rio de Janeiro, Brazil. METHODS: During the study period, 34 NTM isolates from sterile sites o [...] f 14 patients, most of whom were HIV-positive, were submitted to phenotypic identification and hsp65 PCR-restriction enzyme analysis (PRA). RESULTS: Most isolates were identified as Mycobacterium avium, followed by M. monacense, M. kansasii, and M. abscessus. CONCLUSIONS: The combination of PRA, a relatively simple and inexpensive method, with the evaluation of a few phenotypic characteristics can allow NTM to be accurately identified in the routine of clinical laboratories.

Simone Gonçalves, Senna; Ana Grazia, Marsico; Gisele Betzler de Oliveira, Vieira; Luciana Fonseca, Sobral; Philip Noel, Suffys; Leila de Souza, Fonseca.

355

Identificação de micobactérias não tuberculosas isoladas de sítios estéreis em pacientes em um hospital universitário na cidade do Rio de Janeiro / Identification of nontuberculous mycobacteria isolated from clinical sterile sites in patients at a university hospital in the city of Rio de Janeiro, Brazil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Identificar micobactérias não tuberculosas (MNT) isoladas de sítios estéreis em pacientes internados no Hospital Universitário Clementino Fraga Filho, Rio de Janeiro (RJ) entre 2001 e 2006. MÉTODOS: Durante o período do estudo, 34 isolados de MNT de sítios estéreis de 14 pacientes, a maior [...] ia HIV positivos, foram submetidos a identificação fenotípica e hsp65 PCR-restriction enzyme analysis (PRA, análise por enzimas de restrição por PCR do gene hsp65). RESULTADOS: A maioria dos isolados foi identificada como Mycobacterium avium, seguida por M. monacense, M. kansasii e M. abscessus em menores proporções. CONCLUSÕES: A combinação de PRA, um método relativamente simples e de baixo custo, com algumas características fenotípicas pode fornecer a identificação correta de MNT na rotina de laboratórios clínicos. Abstract in english OBJECTIVE: To identify nontuberculous mycobacteria (NTM) isolated from sterile sites in patients hospitalized between 2001 and 2006 at the Clementino Fraga Filho University Hospital, located in the city of Rio de Janeiro, Brazil. METHODS: During the study period, 34 NTM isolates from sterile sites o [...] f 14 patients, most of whom were HIV-positive, were submitted to phenotypic identification and hsp65 PCR-restriction enzyme analysis (PRA). RESULTS: Most isolates were identified as Mycobacterium avium, followed by M. monacense, M. kansasii, and M. abscessus. CONCLUSIONS: The combination of PRA, a relatively simple and inexpensive method, with the evaluation of a few phenotypic characteristics can allow NTM to be accurately identified in the routine of clinical laboratories.

Simone Gonçalves, Senna; Ana Grazia, Marsico; Gisele Betzler de Oliveira, Vieira; Luciana Fonseca, Sobral; Philip Noel, Suffys; Leila de Souza, Fonseca.

2011-08-01

356

Gene therapy in pancreatic cancer  

Science.gov (United States)

Pancreatic cancer (PC) is a highly lethal disease and notoriously difficult to treat. Only a small proportion of PC patients are eligible for surgical resection, whilst conventional chemoradiotherapy only has a modest effect with substantial toxicity. Gene therapy has become a new widely investigated therapeutic approach for PC. This article reviews the basic rationale, gene delivery methods, therapeutic targets and developments of laboratory research and clinical trials in gene therapy of PC by searching the literature published in English using the PubMed database and analyzing clinical trials registered on the Gene Therapy Clinical Trials Worldwide website (http://www. wiley.co.uk/genmed/ clinical). Viral vectors are main gene delivery tools in gene therapy of cancer, and especially, oncolytic virus shows brighter prospect due to its tumor-targeting property. Efficient therapeutic targets for gene therapy include tumor suppressor gene p53, mutant oncogene K-ras, anti-angiogenesis gene VEGFR, suicide gene HSK-TK, cytosine deaminase and cytochrome p450, multiple cytokine genes and so on. Combining different targets or combination strategies with traditional chemoradiotherapy may be a more effective approach to improve the efficacy of cancer gene therapy. Cancer gene therapy is not yet applied in clinical practice, but basic and clinical studies have demonstrated its safety and clinical benefits. Gene therapy will be a new and promising field for the treatment of PC.

Liu, Si-Xue; Xia, Zhong-Sheng; Zhong, Ying-Qiang

2014-01-01

357

Entrez Gene: gene-centered information at NCBI.  

Science.gov (United States)

Entrez Gene (http://www.ncbi.nlm.nih.gov/gene) is National Center for Biotechnology Information (NCBI)'s database for gene-specific information. Entrez Gene maintains records from genomes which have been completely sequenced, which have an active research community to submit gene-specific information, or which are scheduled for intense sequence analysis. The content represents the integration of curation and automated processing from NCBI's Reference Sequence project (RefSeq), collaborating model organism databases, consortia such as Gene Ontology and other databases within NCBI. Records in Entrez Gene are assigned unique, stable and tracked integers as identifiers. The content (nomenclature, genomic location, gene products and their attributes, markers, phenotypes and links to citations, sequences, variation details, maps, expression, homologs, protein domains and external databases) is available via interactive browsing through NCBI's Entrez system, via NCBI's Entrez programming utilities (E-Utilities) and for bulk transfer by FTP. PMID:21115458

Maglott, Donna; Ostell, Jim; Pruitt, Kim D; Tatusova, Tatiana

2011-01-01

358

Radio-induced genes  

International Nuclear Information System (INIS)

The monitoring system of the DNA integrity of an irradiated cell does not satisfy oneself to recruit the enzymes allowing the repair of detected damages. It sends an alarm signal whom transmission leads to the activation of specific genes in charge of stopping the cell cycle, the time to make the repair works, or to lead to the elimination of a too much damaged cell. Among the numerous genes participating to the monitoring of cell response to irradiation, the target genes of the mammalian P53 protein are particularly studied. Caretaker of the genome, this protein play a central part in the cell response to ionizing radiations. this response is less studied among plants. A way to tackle it is to be interested in the radioinduced genes identification in the vegetal cell, while taking advantage of knowledge got in the animal field. The knowledge of the complete genome of the arabette (arabidopsis thaliana), the model plant and the arising of new techniques allow to lead this research at a previously unknown rhythm in vegetal biology. (N.C.)

359

Genes and Vocal Learning  

Science.gov (United States)

Could a mutation in a single gene be the evolutionary lynchpin supporting the development of human language? A rare mutation in the molecule known as FOXP2 discovered in a human family seemed to suggest so, and its sequence phylogeny reinforced a Chomskian view that language emerged wholesale in humans. Spurred by this discovery, research in…

White, Stephanie A.

2010-01-01

360

Exploring Genes & Genetic Disorders  

Science.gov (United States)

More and more excellent data continues to be produced by the Human Genome Project, and a number of government organizations have created top-notch educational resources based on this information. The Gene Gateway website was originally produced as a companion to the Human Genome Landmarks poster and has evolved into a "collection of guides and tutorials designed to help students and other novice users get started with some of the resources that make these data available to the public." Here visitors are introduced to various Internet tools that anyone can use to investigate "genetic disorders, chromosomes, genome maps, genes, sequence data, genetic variants, and molecular structures." Visitors can download the Gene Gateway workbook, which contains five activities, complete with screenshots and step-by-step instructions "designed to introduce new users to genetic disorder and bioinformatics resources on the Web". Moving down the homepage, visitors can look into sections such as "Bioinformatics Tools", the "Genetic Disorder Guide", and an outstanding "Chromosome Viewer". The viewer provides a great backdrop for those seeking to understand the physical makeup of human chromosomes. Also, visitors can order a free copy of the wall poster "Human Genome Landmarks: Selected Genes, Traits, and Disorders".