Nisin depletes ATP and proton motive force in mycobacteria.

Science.gov (United States)

Chung, H J; Montville, T J; Chikindas, M L

2000-12-01

This study examined the inhibitory effect of nisin and its mode of action against Mycobacterium smegmatis, a non-pathogenic species of mycobacteria, and M. bovis-Bacill Carmette Guerin (BCG), a vaccine strain of pathogenic M. bovis. In agar diffusion assays, 2.5 mg ml(-1) nisin was required to inhibit M. bovis-BCG. Nisin caused a slow, gradual, time- and concentration-dependent decrease in internal ATP levels in M. bovis-BCG, but no ATP efflux was detected. In mycobacteria, nisin decreased both components of proton motive force (membrane potential, Delta Psi and Delta pH) in a time- and concentration-dependent manner. However, mycobacteria maintained their intracellular ATP levels during the initial time period of Delta Psi and Delta pH dissipation. These data suggest that the mechanism of nisin in mycobacteria is similar to that in food-borne pathogens.

Differential Macrophage Response to Slow- and Fast-Growing Pathogenic Mycobacteria

Directory of Open Access Journals (Sweden)

A. Cecilia Helguera-Repetto

2014-01-01

Full Text Available Nontuberculous mycobacteria (NTM have recently been recognized as important species that cause disease even in immunocompetent individuals. The mechanisms that these species use to infect and persist inside macrophages are not well characterised. To gain insight concerning this process we used THP-1 macrophages infected with M. abscessus, M. fortuitum, M. celatum, and M. tuberculosis. Our results showed that slow-growing mycobacteria gained entrance into these cells with more efficiency than fast-growing mycobacteria. We have also demonstrated that viable slow-growing M. celatum persisted inside macrophages without causing cell damage and without inducing reactive oxygen species (ROS, as M. tuberculosis caused. In contrast, fast-growing mycobacteria destroyed the cells and induced high levels of ROS. Additionally, the macrophage cytokine pattern induced by M. celatum was different from the one induced by either M. tuberculosis or fast-growing mycobacteria. Our results also suggest that, in some cases, the intracellular survival of mycobacteria and the immune response that they induce in macrophages could be related to their growth rate. In addition, the modulation of macrophage cytokine production, caused by M. celatum, might be a novel immune-evasion strategy used to survive inside macrophages that is different from the one reported for M. tuberculosis.

First detection of mycobacteria in African rodents and insectivores, using stratified pool screening

DEFF Research Database (Denmark)

Durnez, L.; Eddyani, M.; Mgode, G. F.

2007-01-01

With the rising number of patients with human immunodeficiency virus (HIV)/AIDS in developing countries, the control of mycobacteria is of growing importance. Previous studies have shown that rodents and insectivores are carriers of mycobacteria. However, it is not clear how widespread mycobacteria...... spp.) were isolated from C. gambianus, Mastomys natalensis, and C. hirta. This study is the first to report findings of mycobacteria in African rodents and insectivores and the first in mycobacterial ecology to estimate the prevalence of mycobacteria after stratified pool screening. The fact...... that small mammals in urban areas carry more mycobacteria than those in the fields and that potentially pathogenic mycobacteria were isolated identifies a risk for other animals and humans, especially HIV/AIDS patients, that have a weakened immune system. ...

Mycobacteria in Terrestrial Small Mammals on Cattle Farms in Tanzania

DEFF Research Database (Denmark)

Durnez, Lies; Katakweba, Abdul; Sadiki, Harrison

2011-01-01

The control of bovine tuberculosis and atypical mycobacterioses in cattle in developing countries is important but difficult because of the existence of wildlife reservoirs. In cattle farms in Tanzania, mycobacteria were detected in 7.3% of 645 small mammals and in cow's milk. The cattle farms we....... However, because of the high prevalence of mycobacteria in some small mammal species, these infected animals can pose a risk to humans, especially in areas with a high HIV-prevalence as is the case in Tanzania.......The control of bovine tuberculosis and atypical mycobacterioses in cattle in developing countries is important but difficult because of the existence of wildlife reservoirs. In cattle farms in Tanzania, mycobacteria were detected in 7.3% of 645 small mammals and in cow's milk. The cattle farms were...... and PCR in the small mammals were atypical mycobacteria. Analysis of the presence of mycobacteria in relation to the reactor status of the cattle farms does not exclude transmission between small mammals and cattle but indicates that transmission to cattle from another source of infection is more likely...

Mycobacteria in water and loose deposits of drinking water distribution systems in Finland.

Science.gov (United States)

Torvinen, Eila; Suomalainen, Sini; Lehtola, Markku J; Miettinen, Ilkka T; Zacheus, Outi; Paulin, Lars; Katila, Marja-Leena; Martikainen, Pertti J

2004-04-01

Drinking water distribution systems were analyzed for viable counts of mycobacteria by sampling water from waterworks and in different parts of the systems. In addition, loose deposits collected during mechanical cleaning of the main pipelines were similarly analyzed. The study covered 16 systems at eight localities in Finland. In an experimental study, mycobacterial colonization of biofilms on polyvinyl chloride tubes in a system was studied. The isolation frequency of mycobacteria increased from 35% at the waterworks to 80% in the system, and the number of mycobacteria in the positive samples increased from 15 to 140 CFU/liter, respectively. Mycobacteria were isolated from all 11 deposits with an accumulation time of tens of years and from all 4 deposits which had accumulated during a 1-year follow-up time. The numbers of mycobacteria were high in both old and young deposits (medians, 1.8 x 10(5) and 3.9 x 10(5) CFU/g [dry weight], respectively). Both water and deposit samples yielded the highest numbers of mycobacteria in the systems using surface water and applying ozonation as an intermediate treatment or posttreatment. The number and growth of mycobacteria in system waters correlated strongly with the concentration of assimilable organic carbon in the water leaving the waterworks. The densities of mycobacteria in the developing biofilms were highest at the distal sites of the systems. Over 90% of the mycobacteria isolated from water and deposits belonged to Mycobacterium lentiflavum, M. tusciae, M. gordonae, and a previously unclassified group of mycobacteria. Our results indicate that drinking water systems may be a source for recently discovered new mycobacterial species.

Macrolide Resistance in Mycobacteria

Czech Academy of Sciences Publication Activity Database

Doucet-Populaire, F.; Buriánková, Karolína; Weiser, Jaroslav; Pernodet, J.-L.

2005-01-01

Roč. 2, - (2005), s. 511-523 ISSN 0198-6325 R&D Projects: GA ČR GA310/03/0292 Institutional research plan: CEZ:AV0Z50200510 Keywords : mycobacteria * mycobacterium tuberculosis * ribosome Subject RIV: EE - Microbiology, Virology Impact factor: 7.964, year: 2005

Macrophage sphingolipids are essential for the entry of mycobacteria.

Science.gov (United States)

Viswanathan, Gopinath; Jafurulla, Md; Kumar, G Aditya; Raghunand, Tirumalai R; Chattopadhyay, Amitabha

2018-07-01

Mycobacteria are intracellular pathogens that can invade and survive within host macrophages. Mycobacterial infections remain a major cause of mortality and morbidity worldwide, with serious concerns of emergence of multi and extensively drug-resistant tuberculosis. While significant advances have been made in identifying mycobacterial virulence determinants, the detailed molecular mechanism of internalization of mycobacteria into host cells remains poorly understood. Although several studies have highlighted the crucial role of sphingolipids in mycobacterial growth, persistence and establishment of infection, the role of sphingolipids in the entry of mycobacteria into host cells is not known. In this work, we explored the role of host membrane sphingolipids in the entry of Mycobacterium smegmatis into J774A.1 macrophages. Our results show that metabolic depletion of sphingolipids in host macrophages results in a significant reduction in the entry of M. smegmatis. Importantly, the entry of Escherichia coli into host macrophages under similar conditions remained invariant, implying the specificity of the requirement of sphingolipids in mycobacterial entry. To the best of our knowledge, our results constitute the first report demonstrating the role of host macrophage sphingolipids in the entry of mycobacteria. Our results could help in the development of novel therapeutic strategies targeting sphingolipid-mediated entry of mycobacteria into host cells. Copyright © 2018 Elsevier B.V. All rights reserved.

Nontuberculous mycobacteria in captive and pet reptiles

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Irena Reil

2017-01-01

Full Text Available The aim of this study was to highlight the importance of nontuberculous mycobacteria species in the pathology of various reptilian pet species as well as their epidemiological significance of infection transmission to humans. Faeces samples from six living reptiles and organs from ten carcasses were submitted to bacteriological testing during the years 2003–2015. Positive colonies from one faeces sample and two organs showed the presence of a gene coding 65kDa antigen common for all mycobacteria. Further identification to the species level revealed that the isolates belong to Mycobacterium fortuitum and Mycobacterium avium subsp. hominissuis, later subjected to drug susceptibility testing which confirmed high resistance levels in both isolates. In conclusion, there is a great significance of the occurrence of nontuberculous mycobacteria in captive and pet reptiles, presenting reptiles as possible hosts representing a serious threat of transmission of high resistance mycobacterial isolates to humans. To our knowledge, this is the first report of M. avium subsp. hominissuis occurrence in reptiles.

An update on mycobacteria and the development of allergic diseases

NARCIS (Netherlands)

Folkerts, G.

2015-01-01

Mycobacteria can diminish allergic and asthmatic manifestations. This means that mycobacteria could offer therapeutical opportunities as an 'anti-allergic' vaccine.In humans, the genetic background and the environment probably contribute to the development of allergies. Over the last 20. years, a

Isolation of rapid growing mycobacteria from soil and water in Iran

African Journals Online (AJOL)

USER

2010-06-14

Jun 14, 2010 ... an abundant occurrence of mycobacteria in low pH (P value = 0001). We also ..... between large numbers of mycobacterial and high soil acidity as ... (2002). Chlorine disinfection of atypical mycobacteria isolated from a.

Life-threatening mycobacteria infection

NARCIS (Netherlands)

Faber, William R.

2005-01-01

Most mycobacteria cause localized and often harmless infections of the skin, Leprosy. which dates back to approximately 60 BC in India,(1) was supposed to be eliminated as a Public health problem by the year 2000.(2) With a new case detection rate between 600,000 and 700,000 yearly, however.(3)

Prevalence of Nontuberculous Mycobacteria (NTM in Iranian Clinical Specimens: Systematic Review and Meta-Analysis

Directory of Open Access Journals (Sweden)

Azad Khaledi

2017-01-01

Full Text Available Background:    Although, nontuberculous mycobacteria can cause disease in different organisms, they usually are not reported in most countries because scientists in general consider them as non-pathogens. But, increasing nontuberculous mycobacteria diseases occurrence has changed this belief. Nevertheless, there is no meta-analysis review about prevalence of nontuberculous mycobacteria in Iran. Methods:   Any data about prevalence of nontuberculous mycobacteria in clinical specimens in Iran were retrieved by searching data bases such as Pub Med, MEDLINE, and Iranian data bases. Then the meta-analysis was performed by comprehensive meta-analysis software (CMA. Results:    The meta-analysis showed that the prevalence of nontuberculous mycobacteria in the clinical specimens in Iran was 1.3%. In the studies that had sample size less than 300, and in studies conducted after 2004, the prevalence was higher. Also, the prevalence of nontuberculous mycobacteria was higher in the West of Iran. In this study, the most prevalent rapid-growing mycobacterium was Mycobacterium. fortuitum and  most prevalent slow-growing mycobacterium was M. simiae with the prevalence 44.2% and 14.3%, respectively.Conclusion:   M. simiae is the most prevalent nontuberculous mycobacteria in the clinical specimens in Iran. As this species of nontuberculous mycobacteria has similar clinical and radiological manifestations with tuberculosis, it is often treated as tuberculosis. Unfortunately, M. simiae is resistant against first-line anti-TB drugs resulting in treatment failure after using routine anti-TB medication. Therefore, there is an urgent need for application of new diagnostic strategy for identification of nontuberculous mycobacteria species.

Epidemiology of nontuberculous mycobacteria isolations among central North Carolina residents, 2006-2010

Science.gov (United States)

BACKGROUND: Nontuberculous mycobacteria (NTM) are environmental mycobacteria associated with a range of infections. Reports of NTM epidemiology have primarily focused on pulmonary infections and isolations, however extrapulmonary infections of the skin, soft tissues and sterile s...

Role of genotype® mycobacterium common mycobacteria/additional species assay for rapid differentiation between Mycobacterium tuberculosis complex and different species of non-tuberculous mycobacteria

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Amresh Kumar Singh

2013-01-01

Full Text Available Background: Mycobacterium tuberculosis complex (MTBC and non-tuberculous mycobacteria (NTM may or may not have same clinical presentations, but the treatment regimens are always different. Laboratory differentiation between MTBC and NTM by routine methods are time consuming and cumbersome to perform. We have evaluated the role of GenoType® Mycobacterium common mycobacteria/additional species (CM/AS assay for differentiation between MTBC and different species of NTM in clinical isolates from tuberculosis (TB cases. Materials and Methods: A total of 1080 clinical specimens were collected from January 2010 to June 2012. Diagnosis was performed by Ziehl-Neelsen staining followed by culture in BacT/ALERT 3D system (bioMerieux, France. A total of 219 culture positive clinical isolates (BacT/ALERT® MP cultures were selected for differentiation by p-nitrobenzoic acid (PNB sensitivity test as and BIO-LINE SD Ag MPT64 TB test considering as the gold standard test. Final identification and differentiation between MTBC and different species of NTM were further confirmed by GenoType® Mycobacterium CM/AS assay (Hain Lifescience, Nehren, Germany. Results: Out of 219 BacT/ALERT® MP culture positive isolates tested by PNB as 153 MTBC (69.9% and by GenoType® Mycobacterium CM/AS assay as 159 (72.6% MTBC and remaining 60 (27.4% were considered as NTM species. The GenoType® Mycobacterium CM/AS assay was proved 99.3% sensitive and 98.3% specific for rapid differentiation of MTBC and NTM. The most common NTM species were; Mycobacterium fortuitum 20 (33.3% among rapid growing mycobacteria and Mycobacterium intracellulare 11 (18.3% among slow growing mycobacteria. Conclusion: The GenoType® Mycobacterium assay makes rapid and accurate identification of NTM species as compared with different phenotypic and molecular diagnostic tool and helps in management of infections caused by different mycobacteria.

Mycobacteria inactivation using Engineered Water Nanostructures (EWNS).

Science.gov (United States)

Pyrgiotakis, Georgios; McDevitt, James; Gao, Ya; Branco, Alan; Eleftheriadou, Mary; Lemos, Bernardo; Nardell, Edward; Demokritou, Philip

2014-08-01

Airborne transmitted pathogens such as Mycobacterium tuberculosis (Mtb) cause serious, often fatal infectious disease with enormous global health implications. Due to their unique cell wall and slow growth, mycobacteria are among the most resilient microbial forms. Herein we evaluate the ability of an emerging, chemical-free, nanotechnology-based method to inactivate M. parafortuitum (Mtb surrogate). This method is based on the transformation of atmospheric water vapor into engineered water nano-structures (EWNS) via electrospray. We demonstrate that the EWNS can interact with and inactivate airborne mycobacteria, reducing their concentration levels significantly. Additionally, EWNS can inactivate M. parafortuitum on surfaces eight times faster than the control. The mechanism of mycobacteria inactivation was also investigated in this study. It was demonstrated that the EWNS effectively deliver the reactive oxygen species, encapsulated during the electrospray process, to the bacteria oxidizing their cell membrane resulting into inactivation. Overall, this is a method with the potential to become an effective intervention technology in the battle against airborne infections. This study demonstrates the feasibility of mycobacterium inactivation in airborne form or on contact surfaces using electrospray activated water nano-structures. Given that the method is free of toxic chemicals, this might become an important tool in the prevention of mycobacterial infections, which are notoriously hard to treat. Copyright © 2014 Elsevier Inc. All rights reserved.

Th1-skewed tissue responses to a mycolyl glycolipid in mycobacteria-infected rhesus macaques

Energy Technology Data Exchange (ETDEWEB)

Morita, Daisuke; Miyamoto, Ayumi; Hattori, Yuki; Komori, Takaya [Laboratory of Cell Regulation, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Nakamura, Takashi [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812 (Japan); Igarashi, Tatsuhiko [Laboratory of Primate Model, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Harashima, Hideyoshi [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812 (Japan); Sugita, Masahiko [Laboratory of Cell Regulation, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan)

2013-11-08

Highlights: •Glucose monomycolate (GMM) is a marker glycolipid for active tuberculosis. •Tissue responses to GMM involved up-regulation of Th1-attracting chemokines. •Th1-skewed local responses were mounted at the GMM-injected tissue. -- Abstract: Trehalose 6,6′-dimycolate (TDM) is a major glycolipid of the cell wall of mycobacteria with remarkable adjuvant functions. To avoid detection by the host innate immune system, invading mycobacteria down-regulate the expression of TDM by utilizing host-derived glucose as a competitive substrate for their mycolyltransferases; however, this enzymatic reaction results in the concomitant biosynthesis of glucose monomycolate (GMM) which is recognized by the acquired immune system. GMM-specific, CD1-restricted T cell responses have been detected in the peripheral blood of infected human subjects and monkeys as well as in secondary lymphoid organs of small animals, such as guinea pigs and human CD1-transgenic mice. Nevertheless, it remains to be determined how tissues respond at the site where GMM is produced. Here we found that rhesus macaques vaccinated with Mycobacterium bovis bacillus Calmette–Guerin mounted a chemokine response in GMM-challenged skin that was favorable for recruiting T helper (Th)1 T cells. Indeed, the expression of interferon-γ, but not Th2 or Th17 cytokines, was prominent in the GMM-injected tissue. The GMM-elicited tissue response was also associated with the expression of monocyte/macrophage-attracting CC chemokines, such as CCL2, CCL4 and CCL8. Furthermore, the skin response to GMM involved the up-regulated expression of granulysin and perforin. Given that GMM is produced primarily by pathogenic mycobacteria proliferating within the host, the Th1-skewed tissue response to GMM may function efficiently at the site of infection.

Th1-skewed tissue responses to a mycolyl glycolipid in mycobacteria-infected rhesus macaques

International Nuclear Information System (INIS)

Morita, Daisuke; Miyamoto, Ayumi; Hattori, Yuki; Komori, Takaya; Nakamura, Takashi; Igarashi, Tatsuhiko; Harashima, Hideyoshi; Sugita, Masahiko

2013-01-01

Highlights: •Glucose monomycolate (GMM) is a marker glycolipid for active tuberculosis. •Tissue responses to GMM involved up-regulation of Th1-attracting chemokines. •Th1-skewed local responses were mounted at the GMM-injected tissue. -- Abstract: Trehalose 6,6′-dimycolate (TDM) is a major glycolipid of the cell wall of mycobacteria with remarkable adjuvant functions. To avoid detection by the host innate immune system, invading mycobacteria down-regulate the expression of TDM by utilizing host-derived glucose as a competitive substrate for their mycolyltransferases; however, this enzymatic reaction results in the concomitant biosynthesis of glucose monomycolate (GMM) which is recognized by the acquired immune system. GMM-specific, CD1-restricted T cell responses have been detected in the peripheral blood of infected human subjects and monkeys as well as in secondary lymphoid organs of small animals, such as guinea pigs and human CD1-transgenic mice. Nevertheless, it remains to be determined how tissues respond at the site where GMM is produced. Here we found that rhesus macaques vaccinated with Mycobacterium bovis bacillus Calmette–Guerin mounted a chemokine response in GMM-challenged skin that was favorable for recruiting T helper (Th)1 T cells. Indeed, the expression of interferon-γ, but not Th2 or Th17 cytokines, was prominent in the GMM-injected tissue. The GMM-elicited tissue response was also associated with the expression of monocyte/macrophage-attracting CC chemokines, such as CCL2, CCL4 and CCL8. Furthermore, the skin response to GMM involved the up-regulated expression of granulysin and perforin. Given that GMM is produced primarily by pathogenic mycobacteria proliferating within the host, the Th1-skewed tissue response to GMM may function efficiently at the site of infection

Sinusitis from Nontuberculous Mycobacteria in Tap Water

Centers for Disease Control (CDC) Podcasts

Dr. Wellington S. Tichenor. Associate Clinical Professor of Medicine at New York Medical College and in private practice in Manhattan, New York, discusses his investigation of sinusitis from nontuberculous mycobacteria in tap water.

Characterization and Strains of Mycobacteria Isolated from Cattle ...

African Journals Online (AJOL)

Characterization and Strains of Mycobacteria Isolated from Cattle Carcasses in Refrigerated Slaughterhouse Bamako Goal. Y S Kone, A Cisse, S S Sidibe, Z Tarnagda, S Diarra, D Yassa, P Coulibaly, B Traore ...

Mycobacteria emulsified in olive oil-in-water trigger a robust immune response in bladder cancer treatment

Science.gov (United States)

Noguera-Ortega, Estela; Blanco-Cabra, Núria; Rabanal, Rosa Maria; Sánchez-Chardi, Alejandro; Roldán, Mónica; Guallar-Garrido, Sandra; Torrents, Eduard; Luquin, Marina; Julián, Esther

2016-01-01

The hydrophobic composition of mycobacterial cell walls leads to the formation of clumps when attempting to resuspend mycobacteria in aqueous solutions. Such aggregation may interfere in the mycobacteria-host cells interaction and, consequently, influence their antitumor effect. To improve the immunotherapeutic activity of Mycobacterium brumae, we designed different emulsions and demonstrated their efficacy. The best formulation was initially selected based on homogeneity and stability. Both olive oil (OO)- and mineral oil-in-water emulsions better preserved the mycobacteria viability and provided higher disaggregation rates compared to the others. But, among both emulsions, the OO emulsion increased the mycobacteria capacity to induce cytokines’ production in bladder tumor cell cultures. The OO-mycobacteria emulsion properties: less hydrophobic, lower pH, more neutralized zeta potential, and increased affinity to fibronectin than non-emulsified mycobacteria, indicated favorable conditions for reaching the bladder epithelium in vivo. Finally, intravesical OO-M. brumae-treated mice showed a significantly higher systemic immune response, together with a trend toward increased tumor-bearing mouse survival rates compared to the rest of the treated mice. The physicochemical characteristics and the induction of a robust immune response in vitro and in vivo highlight the potential of the OO emulsion as a good delivery vehicle for the mycobacterial treatment of bladder cancer. PMID:27265565

Pathogenic mycobacteria achieve cellular persistence by inhibiting the Niemann-Pick Type C disease cellular pathway.

Science.gov (United States)

Fineran, Paul; Lloyd-Evans, Emyr; Lack, Nathan A; Platt, Nick; Davis, Lianne C; Morgan, Anthony J; Höglinger, Doris; Tatituri, Raju Venkata V; Clark, Simon; Williams, Ian M; Tynan, Patricia; Al Eisa, Nada; Nazarova, Evgeniya; Williams, Ann; Galione, Antony; Ory, Daniel S; Besra, Gurdyal S; Russell, David G; Brenner, Michael B; Sim, Edith; Platt, Frances M

2016-11-18

Tuberculosis remains a major global health concern. The ability to prevent phagosome-lysosome fusion is a key mechanism by which intracellular mycobacteria, including Mycobacterium tuberculosis , achieve long-term persistence within host cells. The mechanisms underpinning this key intracellular pro-survival strategy remain incompletely understood. Host macrophages infected with persistent mycobacteria share phenotypic similarities with cells taken from patients suffering from Niemann-Pick Disease Type C (NPC), a rare lysosomal storage disease in which endocytic trafficking defects and lipid accumulation within the lysosome lead to cell dysfunction and cell death. We investigated whether these shared phenotypes reflected an underlying mechanistic connection between mycobacterial intracellular persistence and the host cell pathway dysfunctional in NPC. The induction of NPC phenotypes in macrophages from wild-type mice or obtained from healthy human donors was assessed via infection with mycobacteria and subsequent measurement of lipid levels and intracellular calcium homeostasis. The effect of NPC therapeutics on intracellular mycobacterial load was also assessed. Macrophages infected with persistent intracellular mycobacteria phenocopied NPC cells, exhibiting accumulation of multiple lipid types, reduced lysosomal Ca 2+ levels, and defects in intracellular trafficking. These NPC phenotypes could also be induced using only lipids/glycomycolates from the mycobacterial cell wall. These data suggest that persistent intracellular mycobacteria inhibit the NPC pathway, likely via inhibition of the NPC1 protein, and subsequently induce altered acidic store Ca 2+ homeostasis. Reduced lysosomal calcium levels may provide a mechanistic explanation for the reduced levels of phagosome-lysosome fusion in mycobacterial infection. Treatments capable of correcting defects in NPC mutant cells via modulation of host cell calcium were of benefit in promoting clearance of mycobacteria

Nontuberculous mycobacteria in Middle East: Current situation and future challenges

Directory of Open Access Journals (Sweden)

Ali Akbar Velayati

2015-01-01

Mycobacterium fortuitum was the most common rapid growing mycobacteria (RGM isolated from both clinical (269 out of 447 RGM; 60.1% and environmental (135 out of 289 RGM; 46.7% samples. Mycobacterium avium complex (MAC was the most common slow growing mycobacteria (SGM isolated from clinical samples (140 out of 637 SGM; 21.9%. An increasing trend in NTM isolation from the Middle East was noted over the last 5 years. This review demonstrates the increasing concern regarding NTM disease in the Middle East, emphasizing the need for regional collaboration and coordination in order to respond appropriately.

Optimal DNA Isolation Method for Detection of Nontuberculous Mycobacteria by Polymerase Chain Reaction.

Science.gov (United States)

Mohammadi, Samira; Esfahani, Bahram Nasr; Moghim, Sharareh; Mirhendi, Hossein; Zaniani, Fatemeh Riyahi; Safaei, Hajieh Ghasemian; Fazeli, Hossein; Salehi, Mahshid

2017-01-01

Nontuberculous mycobacteria (NTM) are a group of opportunistic pathogens and these are widely dispersed in water and soil resources. Identification of mycobacteria isolates by conventional methods including biochemical tests, growth rates, colony pigmentation, and presence of acid-fast bacilli is widely used, but these methods are time-consuming, labor-intensive, and may sometimes remain inconclusive. The DNA was extracted from NTM cultures using CTAB, Chelex, Chelex + Nonidet P-40, FTA ® Elute card, and boiling The quantity and quality of the DNA extracted via these methods were determined using UV-photometer at 260 and 280 nm, and polymerase chain reaction (PCR) amplification of the heat-shock protein 65 gene with serially diluted DNA samples. The CTAB method showed more positive results at 1:10-1:100,000 at which the DNA amount was substantial. With the Chelex method of DNA extraction, PCR amplification was detected at 1:10 and 1:1000 dilutions. According to the electrophoresis results, the CTAB and Chelex DNA extraction methods were more successful in comparison with the others as regard producing suitable concentrations of DNA with the minimum use of PCR inhibitor.

Optimal DNA Isolation Method for Detection of Nontuberculous Mycobacteria by Polymerase Chain Reaction

Directory of Open Access Journals (Sweden)

Samira Mohammadi

2017-01-01

Full Text Available Background: Nontuberculous mycobacteria (NTM are a group of opportunistic pathogens and these are widely dispersed in water and soil resources. Identification of mycobacteria isolates by conventional methods including biochemical tests, growth rates, colony pigmentation, and presence of acid-fast bacilli is widely used, but these methods are time-consuming, labor-intensive, and may sometimes remain inconclusive. Materials and Methods: The DNA was extracted from NTM cultures using CTAB, Chelex, Chelex + Nonidet P-40, FTA® Elute card, and boiling The quantity and quality of the DNA extracted via these methods were determined using UV-photometer at 260 and 280 nm, and polymerase chain reaction (PCR amplification of the heat-shock protein 65 gene with serially diluted DNA samples. Results: The CTAB method showed more positive results at 1:10–1:100,000 at which the DNA amount was substantial. With the Chelex method of DNA extraction, PCR amplification was detected at 1:10 and 1:1000 dilutions. Conclusions: According to the electrophoresis results, the CTAB and Chelex DNA extraction methods were more successful in comparison with the others as regard producing suitable concentrations of DNA with the minimum use of PCR inhibitor.

Stable Regulation of Cell Cycle Events in Mycobacteria: Insights From Inherently Heterogeneous Bacterial Populations.

Science.gov (United States)

Logsdon, Michelle M; Aldridge, Bree B

2018-01-01

Model bacteria, such as E. coli and B. subtilis , tightly regulate cell cycle progression to achieve consistent cell size distributions and replication dynamics. Many of the hallmark features of these model bacteria, including lateral cell wall elongation and symmetric growth and division, do not occur in mycobacteria. Instead, mycobacterial growth is characterized by asymmetric polar growth and division. This innate asymmetry creates unequal birth sizes and growth rates for daughter cells with each division, generating a phenotypically heterogeneous population. Although the asymmetric growth patterns of mycobacteria lead to a larger variation in birth size than typically seen in model bacterial populations, the cell size distribution is stable over time. Here, we review the cellular mechanisms of growth, division, and cell cycle progression in mycobacteria in the face of asymmetry and inherent heterogeneity. These processes coalesce to control cell size. Although Mycobacterium smegmatis and Mycobacterium bovis Bacillus Calmette-Guérin (BCG) utilize a novel model of cell size control, they are similar to previously studied bacteria in that initiation of DNA replication is a key checkpoint for cell division. We compare the regulation of DNA replication initiation and strategies used for cell size homeostasis in mycobacteria and model bacteria. Finally, we review the importance of cellular organization and chromosome segregation relating to the physiology of mycobacteria and consider how new frameworks could be applied across the wide spectrum of bacterial diversity.

Urease testing of mycobacteria with BACTEC radiometric instrumentation

International Nuclear Information System (INIS)

Damato, J.J.; Collins, M.T.; McClatchy, J.K.

1982-01-01

A total of 140 mycobacterial isolates from patients treated at Fitzsimons Army Medical Center or the National Jewish Hospital and Research Center and from animal specimens submitted to the National Veterinary Services Laboratory were tested by using a urease procedure modified for use with a BACTEC model 301. Mycobacterial suspensions were prepared by using Middlebrook 7H10 Tween broth. Of the 98 mycobacteria isolates which were urease positive utilizing standard methodology, all were positive using the radiometric procedures. Similarly, all 42 urease-negative isolates were also negative employing the new methodology. Although maximum radiometric readings were observed at 48 h, all positive strains were readily identified 24 h after inoculation without sacrificing either test sensitivity or specificity. Thus, urease testing of mycobacteria, using the modified BACTEC radiometric methodology, was as sensitive, as specific, and more rapid than conventional methods

Structural insights into the mycobacteria transcription initiation complex from analysis of X-ray crystal structures

Energy Technology Data Exchange (ETDEWEB)

Hubin, Elizabeth A.; Lilic, Mirjana; Darst, Seth A.; Campbell, Elizabeth A.

2017-07-13

The mycobacteria RNA polymerase (RNAP) is a target for antimicrobials against tuberculosis, motivating structure/function studies. Here we report a 3.2 Å-resolution crystal structure of a Mycobacterium smegmatis (Msm) open promoter complex (RPo), along with structural analysis of the Msm RPo and a previously reported 2.76 Å-resolution crystal structure of an Msm transcription initiation complex with a promoter DNA fragment. We observe the interaction of the Msm RNAP α-subunit C-terminal domain (αCTD) with DNA, and we provide evidence that the αCTD may play a role in Mtb transcription regulation. Our results reveal the structure of an Actinobacteria-unique insert of the RNAP β' subunit. Finally, our analysis reveals the disposition of the N-terminal segment of Msm σA, which may comprise an intrinsically disordered protein domain unique to mycobacteria. The clade-specific features of the mycobacteria RNAP provide clues to the profound instability of mycobacteria RPo compared with E. coli.

RNA-seq analysis of mycobacteria stress response to microgravity

Data.gov (United States)

National Aeronautics and Space Administration — The aim of this work is to determine whether mycobacteria have enhanced virulence during space travel and what mechanisms they use to adapt to microgravity. M....

Stable Regulation of Cell Cycle Events in Mycobacteria: Insights From Inherently Heterogeneous Bacterial Populations

Directory of Open Access Journals (Sweden)

Michelle M. Logsdon

2018-03-01

Full Text Available Model bacteria, such as E. coli and B. subtilis, tightly regulate cell cycle progression to achieve consistent cell size distributions and replication dynamics. Many of the hallmark features of these model bacteria, including lateral cell wall elongation and symmetric growth and division, do not occur in mycobacteria. Instead, mycobacterial growth is characterized by asymmetric polar growth and division. This innate asymmetry creates unequal birth sizes and growth rates for daughter cells with each division, generating a phenotypically heterogeneous population. Although the asymmetric growth patterns of mycobacteria lead to a larger variation in birth size than typically seen in model bacterial populations, the cell size distribution is stable over time. Here, we review the cellular mechanisms of growth, division, and cell cycle progression in mycobacteria in the face of asymmetry and inherent heterogeneity. These processes coalesce to control cell size. Although Mycobacterium smegmatis and Mycobacterium bovis Bacillus Calmette-Guérin (BCG utilize a novel model of cell size control, they are similar to previously studied bacteria in that initiation of DNA replication is a key checkpoint for cell division. We compare the regulation of DNA replication initiation and strategies used for cell size homeostasis in mycobacteria and model bacteria. Finally, we review the importance of cellular organization and chromosome segregation relating to the physiology of mycobacteria and consider how new frameworks could be applied across the wide spectrum of bacterial diversity.

Double-Strand DNA Break Repair in Mycobacteria.

Science.gov (United States)

Glickman, Michael S

2014-10-01

Discontinuity of both strands of the chromosome is a lethal event in all living organisms because it compromises chromosome replication. As such, a diversity of DNA repair systems has evolved to repair double-strand DNA breaks (DSBs). In part, this diversity of DSB repair systems has evolved to repair breaks that arise in diverse physiologic circumstances or sequence contexts, including cellular states of nonreplication or breaks that arise between repeats. Mycobacteria elaborate a set of three genetically distinct DNA repair pathways: homologous recombination, nonhomologous end joining, and single-strand annealing. As such, mycobacterial DSB repair diverges substantially from the standard model of prokaryotic DSB repair and represents an attractive new model system. In addition, the presence in mycobacteria of a DSB repair system that can repair DSBs in nonreplicating cells (nonhomologous end joining) or when DSBs arise between repeats (single-strand annealing) has clear potential relevance to Mycobacterium tuberculosis pathogenesis, although the exact role of these systems in M. tuberculosis pathogenesis is still being elucidated. In this article we will review the genetics of mycobacterial DSB repair systems, focusing on recent insights.

Sinusitis from Nontuberculous Mycobacteria in Tap Water

Centers for Disease Control (CDC) Podcasts

2012-12-21

Dr. Wellington S. Tichenor. Associate Clinical Professor of Medicine at New York Medical College and in private practice in Manhattan, New York, discusses his investigation of sinusitis from nontuberculous mycobacteria in tap water.  Created: 12/21/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 12/31/2012.

Malachite green interferes with postantibiotic recovery of mycobacteria.

Science.gov (United States)

Gelman, Ekaterina; McKinney, John D; Dhar, Neeraj

2012-07-01

The genus Mycobacterium comprises slow-growing species with generation times ranging from hours to weeks. The protracted incubation time before colonies appear on solid culture medium can result in overgrowth by faster-growing microorganisms. To prevent contamination, the solid media used in laboratories and clinics for cultivation of mycobacteria contain the arylmethane compound malachite green, which has broad-spectrum antimicrobial activity. Malachite green has no impact on the plating efficiency of mycobacteria when cells are grown under normal conditions. However, we found that malachite green interfered with colony formation when bacteria were preexposed to antibiotics targeting cell wall biogenesis (isoniazid, ethionamide, ethambutol). This inhibitory effect of malachite green was not observed when bacteria were preexposed to antibiotics targeting cellular processes other than cell wall biogenesis (rifampin, moxifloxacin, streptomycin). Sputum specimens from tuberculosis patients are routinely evaluated on solid culture medium containing high concentrations of malachite green. This practice could lead to underestimation of bacterial loads and overestimation of chemotherapeutic efficacy.

ESX-1-mediated translocation to the cytosol controls virulence of mycobacteria

KAUST Repository

Houben, Diane; Demangel, Caroline; Van Ingen, Jakko; Perez, Jorge; Baldeó n, Lucy R.; Abdallah, Abdallah; Caleechurn, Laxmee; Bottai, Daria; Van Zon, Maaike; De Punder, Karin; Van Der Laan, Tridia; Kant, Arie; Bossers-De Vries, Ruth; Willemsen, Peter Th J; Bitter, Wilbert M.; Van Soolingen, Dick; Brosch, Roland; Van Der Wel, Nicole N.; Peters, Peter J.

2012-01-01

Mycobacterium species, including Mycobacterium tuberculosis and Mycobacterium leprae, are among the most potent human bacterial pathogens. The discovery of cytosolic mycobacteria challenged the paradigm that these pathogens exclusively localize within the phagosome of host cells. As yet the biological relevance of mycobacterial translocation to the cytosol remained unclear. In this current study we used electron microscopy techniques to establish a clear link between translocation and mycobacterial virulence. Pathogenic, patient-derived mycobacteria species were found to translocate to the cytosol, while non-pathogenic species did not. We were further able to link cytosolic translocation with pathogenicity by introducing the ESX-1 (type VII) secretion system into the non-virulent, exclusively phagolysosomal Mycobacterium bovis BCG. Furthermore, we show that translocation is dependent on the C-terminus of the early-secreted antigen ESAT-6. The C-terminal truncation of ESAT-6 was shown to result in attenuation in mice, again linking translocation to virulence. Together, these data demonstrate the molecular mechanism facilitating translocation of mycobacteria. The ability to translocate from the phagolysosome to the cytosol is with this study proven to be biologically significant as it determines mycobacterial virulence. © 2012 Blackwell Publishing Ltd.

ESX-1-mediated translocation to the cytosol controls virulence of mycobacteria

KAUST Repository

Houben, Diane

2012-05-08

Mycobacterium species, including Mycobacterium tuberculosis and Mycobacterium leprae, are among the most potent human bacterial pathogens. The discovery of cytosolic mycobacteria challenged the paradigm that these pathogens exclusively localize within the phagosome of host cells. As yet the biological relevance of mycobacterial translocation to the cytosol remained unclear. In this current study we used electron microscopy techniques to establish a clear link between translocation and mycobacterial virulence. Pathogenic, patient-derived mycobacteria species were found to translocate to the cytosol, while non-pathogenic species did not. We were further able to link cytosolic translocation with pathogenicity by introducing the ESX-1 (type VII) secretion system into the non-virulent, exclusively phagolysosomal Mycobacterium bovis BCG. Furthermore, we show that translocation is dependent on the C-terminus of the early-secreted antigen ESAT-6. The C-terminal truncation of ESAT-6 was shown to result in attenuation in mice, again linking translocation to virulence. Together, these data demonstrate the molecular mechanism facilitating translocation of mycobacteria. The ability to translocate from the phagolysosome to the cytosol is with this study proven to be biologically significant as it determines mycobacterial virulence. © 2012 Blackwell Publishing Ltd.

Resistance mechanisms and drug susceptibility testing of nontuberculous mycobacteria.

NARCIS (Netherlands)

Ingen, J. van; Boeree, M.J.; Soolingen, D. van; Mouton, J.W.

2012-01-01

Nontuberculous mycobacteria (NTM) are increasingly recognized as causative agents of opportunistic infections in humans. For most NTM infections the therapy of choice is drug treatment, but treatment regimens differ by species, in particular between slow (e.g. Mycobacterium avium complex,

[Soft-tissue infections due to non-tuberculous mycobacteria following mesotherapy. What is the price of beauty].

Science.gov (United States)

Rivera-Olivero, Ismar Alejandra; Guevara, Armando; Escalona, Arnelly; Oliver, Margarita; Pérez-Alfonzo, Ricardo; Piquero, Jaime; Zerpa, Olga; de Waard, Jacobus H

2006-05-01

Mesotherapy is widely used In Latin America for cosmetic purposes, particularly in obese individuals. We describe the clinical and epidemiological characteristics, microbiological diagnosis, treatment and follow-up of patients from Caracas (Venezuela) with soft tissue infection caused by non-tuberculous mycobacteria following mesotherapy. Between March 2002 and December 2003, we evaluated 49 cases of skin and soft tissue infection following mesotherapy. Specimens obtained from the lesions and 15 products used in the mesotherapy procedure were cultured for the presence of non-tuberculous mycobacteria. Isolated mycobacteria were identified by PCR restriction fragment length polymorphism analysis of the hsp65 gene. Infection by non-tuberculous mycobacteria was confirmed in 81.6% of the 49 cases. Mycobacterium abscessus and M. fortuitum were the most common species, but M. chelonae, M. peregrinum, M. simiae and a new species that was designated "M. cosmeticum" were also isolated. Patients were treated with species-specific antibiotic agents for 3 to 18 months. Investigation into the source of the infection revealed that 21 patients were clustered within 3 different outbreaks and two products were found to be contaminated with M. fortuitum and M. abscessus, respectively. Physicians should be alerted to the possibility of infection by non-tuberculous mycobacteria in patients with a history of mesotherapy who develop late-onset skin and soft tissue infection, particularly if they do not respond to conventional antibiotic treatment.

'Emerging' mycobacteria in South Africa : review article

Directory of Open Access Journals (Sweden)

P.D. Van Helden

2009-05-01

Full Text Available Disease can be caused by various species of the genus Mycobacterium. A number of reports, both published and unpublished, of rarely reported mycobacteria have surfaced in South Africa in the last few years. Some unusual hosts have also been involved, causing concern in some quarters.These include reports on Mycobacterium goodii in a spotted hyaena (Crocuta crocuta, M. xenopi in a ruffed lemur (Varecia variegata, M. intracellulare in wild-caught chacma baboons (Papio ursinus, the 'dassie bacillus' in free ranging rock hyrax (dassies; Procavia capensis the 'oryx bacillus' from free-ranging buffalo (Syncerus caffer and M. tuberculosis in suricates (Suricata suricatta, a domestic dog and in baboons. In this article it has been attempted to put these in context and show how improved surveillance and technologies have allowed mycobacteria to be identified to species level more easily. Most of the unusual mycobacterial species have most likely been present in the region for many years and have probably caused disease episodes before, but have been misdiagnosed. Each case must be evaluated carefully with respect to the animal species involved, the environment in which the host is found and the mycobacterial species, and operational decisions made accordingly.

The Comparison of Biochemical and Sequencing 16S rDNA Gene Methods to Identify Nontuberculous Mycobacteria

Directory of Open Access Journals (Sweden)

Shafipour1, M.

2014-11-01

Full Text Available The identification of Mycobacteria in the species level has great medical importance. Biochemical tests are laborious and time-consuming, so new techniques could be used to identify the species. This research aimed to the comparison of biochemical and sequencing 16S rDNA gene methods to identify nontuberculous Mycobacteria in patients suspected to tuberculosis in Golestan province which is the most prevalent region of tuberculosis in Iran. Among 3336 patients suspected to tuberculosis referred to hospitals and health care centres in Golestan province during 2010-2011, 319 (9.56% culture positive cases were collected. Identification of species by using biochemical tests was done. On the samples recognized as nontuberculous Mycobacteria, after DNA extraction by boiling, 16S rDNA PCR was done and their sequencing were identified by NCBI BLAST. Of the 319 positive samples in Golestan Province, 300 cases were M.tuberculosis and 19 cases (5.01% were identified as nontuberculous Mycobacteria by biochemical tests. 15 out of 19 nontuberculous Mycobacteria were identified by PCR and sequencing method as similar by biochemical methods (similarity rate: 78.9%. But after PCR, 1 case known as M.simiae by biochemical test was identified as M. lentiflavum and 3 other cases were identified as Nocardia. Biochemical methods corresponded to the 16S rDNA PCR and sequencing in 78.9% of cases. However, in identification of M. lentiflavum and Nocaria sp. the molecular method is better than biochemical methods.

Nontuberculous mycobacteria in Middle East: Current situation and future challenges.

Science.gov (United States)

Velayati, Ali Akbar; Rahideh, Sanaz; Nezhad, Zahra Derakhshani; Farnia, Parissa; Mirsaeidi, Mehdi

2015-03-01

Nontuberculous mycobacteria (NTM) are a diverse group of bacterial species that are distributed in the environment. Many of these environmental bacteria can cause disease in humans. The identification of NTM in environmental sources is important for both clinical and epidemiological purposes. In this study, the distribution of NTM species from environmental and clinical samples in the Middle East was reviewed. In order to provide an overview of NTM, as well as recent epidemiological trends, all studies addressing NTM in the Middle East from 1984 to 2014 were reviewed. A total of 96 articles were found, in which 1751 NTM strains were isolated and 1084 of which were obtained from clinical samples, 619 from environmental samples and 48 were cited by case reports. Mycobacterium fortuitum was the most common rapid growing mycobacteria (RGM) isolated from both clinical (269 out of 447 RGM; 60.1%) and environmental (135 out of 289 RGM; 46.7%) samples. Mycobacterium avium complex (MAC) was the most common slow growing mycobacteria (SGM) isolated from clinical samples (140 out of 637 SGM; 21.9%). An increasing trend in NTM isolation from the Middle East was noted over the last 5years. This review demonstrates the increasing concern regarding NTM disease in the Middle East, emphasizing the need for regional collaboration and coordination in order to respond appropriately. Copyright © 2015 Asian African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

Subcellular trafficking of mycobacteria : Implications for virulence and immunogenicity

NARCIS (Netherlands)

Houben, D.

2011-01-01

The aim of this thesis is to determine the properties of the compartment where mycobacteria end up after phagocytosis and which mycobacterial genes play a role in this process. In most cases, bacterial pathogens are taken up by the cell, processed in the endocytic pathway and eventually bacterial

IFN-γ fails to overcome inhibition of selected macrophage activation events in response to pathogenic mycobacteria.

Directory of Open Access Journals (Sweden)

Shyamala Thirunavukkarasu

Full Text Available According to most models of mycobacterial infection, inhibition of the pro-inflammatory macrophage immune responses contributes to the persistence of bacteria. Mycobacterium avium subsp. paratuberculosis (MAP is a highly successful pathogen in cattle and sheep and is also implicated as the causative agent of Crohn's disease in humans. Pathogenic mycobacteria such as MAP have developed multiple strategies to evade host defence mechanisms including interfering with the macrophages' capacity to respond to IFN-γ, a feature which might be lacking in non-pathogenic mycobacteria such as M. smegmatis. We hypothesized that pre-sensitisation of macrophages with the pro-inflammatory cytokine IFN-γ would help in overcoming the inhibitory effect of MAP or its antigens on macrophage inflammatory responses. Herein we have compared a series of macrophage activation parameters in response to MAP and M. smegmatis as well as mycobacterial antigens. While IFN-γ did overcome the inhibition in immune suppressive mechanisms in response to MAP antigen as well as M. smegmatis, we could not find a clear role for IFN-γ in overcoming the inhibition of macrophage inflammatory responses to the pathogenic mycobacterium, MAP. We demonstrate that suppression of macrophage defence mechanisms by pathogenic mycobacteria is unlikely to be overcome by prior sensitization with IFN-γ alone. This indicates that IFN-γ signaling pathway-independent mechanisms may exist for overcoming inhibition of macrophage effector functions in response to pathogenic mycobacteria. These findings have important implications in understanding the survival mechanisms of pathogenic mycobacteria directed towards finding better therapeutics and vaccination strategies.

Surgical site infections due to rapidly growing mycobacteria in puducherry, India.

Science.gov (United States)

Kannaiyan, Kavitha; Ragunathan, Latha; Sakthivel, Sulochana; Sasidar, A R; Muralidaran; Venkatachalam, G K

2015-03-01

Rapidly growing Mycobacteria are increasingly recognized, nowadays as an important pathogen that can cause wide range of clinical syndromes in humans. We herein describe unrelated cases of surgical site infection caused by Rapidly growing Mycobacteria (RGM), seen during a period of 12 months. Nineteen patients underwent operations by different surgical teams located in diverse sections of Tamil Nadu, Pondicherry, Karnataka, India. All patients presented with painful, draining subcutaneous nodules at the infection sites. Purulent material specimens were sent to the microbiology laboratory. Gram stain and Ziehl-Neelsen staining methods were used for direct examination. Culture media included blood agar, chocolate agar, MacConkey agar, Sabourauds agar and Lowenstein-Jensen medium for Mycobacteria. Isolated microorganisms were identified and further tested for antimicrobial susceptibility by standard microbiologic procedures. Mycobacterium fortuitum and M.chelonae were isolated from the purulent drainage obtained from wounds by routine microbiological techniques from all the specimens. All isolates analyzed for antimicrobial susceptibility pattern were sensitive to clarithromycin, linezolid and amikacin but were variable to ciprofloxacin, rifampicin and tobramycin. Our case series highlights that a high level of clinical suspicion should be maintained for patients presenting with protracted soft tissue lesions with a history of trauma or surgery as these infections not only cause physical but also emotional distress that affects both the patients and the surgeon.

Mycobacteria-specific cytokine responses as correlates of treatment response in active and latent tuberculosis.

Science.gov (United States)

Clifford, Vanessa; Tebruegge, Marc; Zufferey, Christel; Germano, Susie; Forbes, Ben; Cosentino, Lucy; McBryde, Emma; Eisen, Damon; Robins-Browne, Roy; Street, Alan; Denholm, Justin; Curtis, Nigel

2017-08-01

A biomarker indicating successful tuberculosis (TB) therapy would assist in determining appropriate length of treatment. This study aimed to determine changes in mycobacteria-specific antigen-induced cytokine biomarkers in patients receiving therapy for latent or active TB, to identify biomarkers potentially correlating with treatment success. A total of 33 adults with active TB and 36 with latent TB were followed longitudinally over therapy. Whole blood stimulation assays using mycobacteria-specific antigens (CFP-10, ESAT-6, PPD) were done on samples obtained at 0, 1, 3, 6 and 9 months. Cytokine responses (IFN-γ, IL-1ra, IL-2, IL-10, IL-13, IP-10, MIP-1β, and TNF-α) in supernatants were measured by Luminex xMAP immunoassay. In active TB cases, median IL-1ra (with CFP-10 and with PPD stimulation), IP-10 (CFP-10, ESAT-6), MIP-1β (ESAT-6, PPD), and TNF-α (ESAT-6) responses declined significantly over the course of therapy. In latent TB cases, median IL-1ra (CFP-10, ESAT-6, PPD), IL-2 (CFP-10, ESAT-6), and IP-10 (CFP-10, ESAT-6) responses declined significantly. Mycobacteria-specific cytokine responses change significantly over the course of therapy, and their kinetics in active TB differ from those observed in latent TB. In particular, mycobacteria-specific IL-1ra responses are potential correlates of successful therapy in both active and latent TB. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Specific Proteins in Nontuberculous Mycobacteria: New Potential Tools

Directory of Open Access Journals (Sweden)

Patricia Orduña

2015-01-01

Full Text Available Nontuberculous mycobacteria (NTM have been isolated from water, soil, air, food, protozoa, plants, animals, and humans. Although most NTM are saprophytes, approximately one-third of NTM have been associated with human diseases. In this study, we did a comparative proteomic analysis among five NTM strains isolated from several sources. There were different numbers of protein spots from M. gordonae (1,264, M. nonchromogenicum type I (894, M. nonchromogenicum type II (935, M. peregrinum (806, and M. scrofulaceum/Mycobacterium mantenii (1,486 strains, respectively. We identified 141 proteins common to all strains and specific proteins to each NTM strain. A total of 23 proteins were selected for its identification. Two of the common proteins identified (short-chain dehydrogenase/reductase SDR and diguanylate cyclase did not align with M. tuberculosis complex protein sequences, which suggest that these proteins are found only in the NTM strains. Some of the proteins identified as common to all strains can be used as markers of NTM exposure and for the development of new diagnostic tools. Additionally, the specific proteins to NTM strains identified may represent potential candidates for the diagnosis of diseases caused by these mycobacteria.

Tuberculosis and non-tuberculous mycobacteria among HIV-infected individuals in Ghana

DEFF Research Database (Denmark)

Bjerrrum, Stephanie; Oliver-Commey, Joseph; Kenu, Ernest

2016-01-01

OBJECTIVES: To assess the prevalence and clinical importance of previously unrecognised tuberculosis (TB) and isolation of non-tuberculous mycobacteria (NTM) among HIV-infected individuals in a teaching hospital in Ghana. METHODS: Intensified mycobacterial case finding was conducted among HIV...... for mycobacteria with smear microscopy, culture and Xpert MTB/RIF assay. NTM species were identified with the GenoType Mycobacterium CM/AS or sequence analysis of 16S rRNA gene. RESULTS: Of 473 participants, 60 (12.7%) had confirmed pulmonary TB, and 38 (8.0%) had positive cultures for NTM. Mycobacterium avium...... cell count, BMI, prolonged fever and ART initiation. CONCLUSIONS: Intensified mycobacterial screening of HIV-infected individuals revealed a high burden of unrecognised pulmonary TB before ART initiation, which increased risk of death within six months. NTM were frequently isolated and associated...

Azurophil granule proteins constitute the major mycobactericidal proteins in human neutrophils and enhance the killing of mycobacteria in macrophages.

Directory of Open Access Journals (Sweden)

Prajna Jena

Full Text Available Pathogenic mycobacteria reside in, and are in turn controlled by, macrophages. However, emerging data suggest that neutrophils also play a critical role in innate immunity to tuberculosis, presumably by their different antibacterial granule proteins. In this study, we purified neutrophil azurophil and specific granules and systematically analyzed the antimycobacterial activity of some purified azurophil and specific granule proteins against M. smegmatis, M. bovis-BCG and M. tuberculosis H37Rv. Using gel overlay and colony forming unit assays we showed that the defensin-depleted azurophil granule proteins (AZP were more active against mycobacteria compared to other granule proteins and cytosolic proteins. The proteins showing antimycobacterial activity were identified by MALDI-TOF mass spectrometry. Electron microscopic studies demonstrate that the AZP disintegrate bacterial cell membrane resulting in killing of mycobacteria. Exogenous addition of AZP to murine macrophage RAW 264.7, THP-1 and peripheral blood monocyte-derived macrophages significantly reduced the intracellular survival of mycobacteria without exhibiting cytotoxic activity on macrophages. Immunofluorescence studies showed that macrophages actively endocytose neutrophil granular proteins. Treatment with AZP resulted in increase in co-localization of BCG containing phagosomes with lysosomes but not in increase of autophagy. These data demonstrate that neutrophil azurophil proteins may play an important role in controlling intracellular survival of mycobacteria in macrophages.

Characterization of mycobacteria in HIV/AIDS patients of Nepal.

Science.gov (United States)

Dhungana, G P; Ghimire, P; Sharma, S; Rijal, B P

2008-01-01

Besides Mycobacterium tuberculosis, a number of other Mycobacterium species are also occasional human pathogens. Tuberculosis due to Mycobacterium avium complex (MAC) and Mycobacterium kansasii is particularly prevalent in AIDS patients as compared to the normal population. A cross-sectional study was carried out during January 2004 to August 2005 in 100 HIV-infected persons visiting Tribhuvan University, Teaching Hospital, and about a dozen of HIV/AIDS care centers of Kathmandu with the objectives to characterize the different mycobacterial species in HIV/AIDS patients. Three sputum specimens from each person were used to investigate tuberculosis by Ziehl-Neelsen staining, culture and identification tests. Among the 100 HIV-infected cases, 66 (66%) were males and 34 (34%) were females. Sixty percent of the cases were in the age group of 21-30 years. Mycobacteria were detected in 23 (23%) HIV cases of which 15 (65.2%) were in the age group of 21-30 years ; 17(74%) were males and 6 (26 %) were females. Among 23 co-infected cases, 22 were culture positive for mycobacteria. Among these, the predominant one was Mycobacterium avium complex (MAC), 9 (41%), followed by M. tuberculosis, 6 (27%), M .kansasii, 4 (18%), M. fortuitum, 2 (10%) and M. chelonae 1 (4%). Significant relationship was established between smoking/alcoholism and the subsequent development of tuberculosis (chi(2)=7.24, p<0.05 for smoking habit and chi(2)=4.39, p<0.05 for alcoholism). Fourteen (61%) co-infected cases presented with weight loss and cough whereas diarrhea was presented only by those patients with atypical mycobacterial co-infection, which was as high as 5 (56%) in patients with MAC co-infection. This study demonstrated the predominance of atypical mycobacteria, mainly MAC, in HIV/AIDS cases and most of them were from sputum smear-negative cases.

AAA+ Machines of Protein Destruction in Mycobacteria.

Science.gov (United States)

Alhuwaider, Adnan Ali H; Dougan, David A

2017-01-01

The bacterial cytosol is a complex mixture of macromolecules (proteins, DNA, and RNA), which collectively are responsible for an enormous array of cellular tasks. Proteins are central to most, if not all, of these tasks and as such their maintenance (commonly referred to as protein homeostasis or proteostasis) is vital for cell survival during normal and stressful conditions. The two key aspects of protein homeostasis are, (i) the correct folding and assembly of proteins (coupled with their delivery to the correct cellular location) and (ii) the timely removal of unwanted or damaged proteins from the cell, which are performed by molecular chaperones and proteases, respectively. A major class of proteins that contribute to both of these tasks are the AAA+ (ATPases associated with a variety of cellular activities) protein superfamily. Although much is known about the structure of these machines and how they function in the model Gram-negative bacterium Escherichia coli , we are only just beginning to discover the molecular details of these machines and how they function in mycobacteria. Here we review the different AAA+ machines, that contribute to proteostasis in mycobacteria. Primarily we will focus on the recent advances in the structure and function of AAA+ proteases, the substrates they recognize and the cellular pathways they control. Finally, we will discuss the recent developments related to these machines as novel drug targets.

Identification of a Novel Conjugative Plasmid in Mycobacteria That Requires Both Type IV and Type VII Secretion

KAUST Repository

Ummels, R.

2014-09-23

Conjugative plasmids have been identified in a wide variety of different bacteria, ranging from proteobacteria to firmicutes, and conjugation is one of the most efficient routes for horizontal gene transfer. The most widespread mechanism of plasmid conjugation relies on different variants of the type IV secretion pathway. Here, we describe the identification of a novel type of conjugative plasmid that seems to be unique for mycobacteria. Interestingly, while this plasmid is efficiently exchanged between different species of slow-growing mycobacteria, including Mycobacterium tuberculosis, it could not be transferred to any of the fast-growing mycobacteria tested. Genetic analysis of the conjugative plasmid showed the presence of a locus containing homologues of three type IV secretion system components and a relaxase. In addition, a new type VII secretion locus was present. Using transposon insertion mutagenesis, we show that in fact both these secretion systems are essential for conjugation, indicating that this plasmid represents a new class of conjugative plasmids requiring two secretion machineries. This plasmid could form a useful new tool to exchange or introduce DNA in slow-growing mycobacteria. IMPORTANCE: Conjugative plasmids play an important role in horizontal gene transfer between different bacteria and, as such, in their adaptation and evolution. This effect is most obvious in the spread of antibiotic resistance genes. Thus far, conjugation of natural plasmids has been described only rarely for mycobacterial species. In fact, it is generally accepted that M. tuberculosis does not show any recent sign of horizontal gene transfer. In this study, we describe the identification of a new widespread conjugative plasmid that can also be efficiently transferred to M. tuberculosis. This plasmid therefore poses both a threat and an opportunity. The threat is that, through the acquisition of antibiotic resistance markers, this plasmid could start a rapid spread of

[Identification of mycobacteria to the species level by molecular methods in the Public Health Laboratory of Bogotá, Colombia].

Science.gov (United States)

Hernández-Toloza, Johana Esther; Rincón-Serrano, María de Pilar; Celis-Bustos, Yamile Adriana; Aguillón, Claudia Inés

2016-01-01

Global epidemiology of non-tuberculous mycobacteria (NTM) is unknown due to the fact that notification is not required in many countries, however the number of infection reports and outbreaks caused by NTM suggest a significant increase in the last years. Traditionally, mycobacteria identification is made through biochemical profiles which allow to differentiate M. tuberculosis from NTM, and in some cases the mycobacteria species. Nevertheless, these methods are technically cumbersome and time consuming. On the other hand, the introduction of methods based on molecular biology has improved the laboratory diagnosis of NTM. To establish the NTM frequency in positive cultures for acid-fast bacilli (AAFB) which were sent to Laboratorio de Salud Pública de Bogotá over a 12 month period. A total of 100 positive cultures for acid-fast bacilli from public and private hospitals from Bogotá were identified by both biochemical methods and the molecular methods PRA (PCR-restriction enzyme analysis) and multiplex-PCR. Furthermore, low prevalence mycobacteria species and non-interpretable results were confirmed by 16SrDNA sequentiation analysis. Identification using the PRA method showed NMT occurrence in 11% of cultures. In addition, this molecular methodology allowed to detect the occurrence of more than one mycobacteria in 4% of the cultures. Interestingly, a new M. kubicae pattern of PCR-restriction analysis is reported in our study. Using a mycobacteria identification algorithm, which includes the molecular method PRA, improves the diagnostic power of conventional methods and could help to advance both NTM epidemiology knowledge and mycobacteriosis control. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Epidemiology of nontuberculous mycobacteria among patients with cystic fibrosis in Scandinavia

DEFF Research Database (Denmark)

Qvist, Tavs; Gilljam, Marita; Jönsson, Bodil

2015-01-01

BACKGROUND: Nontuberculous mycobacteria (NTM) are an emerging threat to cystic fibrosis (CF) patients but their epidemiology is not well described. METHODS: In this retrospective observational study we identified all Scandinavian CF patients with a positive NTM culture from airway secretions from...

In vitro Anti-mycobacteria Sensitivity and Kill-kinetics of Allium ...

African Journals Online (AJOL)

Allium ascalonicum L. (Shallot) was one of the herbs repeatedly identified from the result of our ethnobotanical survey for the treatment of tuberculosis and nontuberculous mycobacteria diseases. It has been reported to show inhibitory potentials against several pathogens. This plant is also known to form part of the diet of ...

Isolation of mycobacteria other than Mycobacterium avium from porcine lymph nodes

NARCIS (Netherlands)

Ingen, van J.; Wisselink, H.J.; Solt-Smits, van C.B.; Boeree, M.J.; Soolingen, D.

2010-01-01

Mycobacterium avium causes lymphadenitis in pigs. This presents an economical burden, as these pigs meat is considered inappropriate for consumption. In humans, lymphadenitis due to nontuberculous mycobacteria (NTM) primarily affects children and is caused by a variety of NTM, though M. avium

Isolation of mycobacteria other than Mycobacterium avium from porcine lymph nodes.

NARCIS (Netherlands)

Ingen, J. van; Wisselink, H.J.; Solt-Smits, C.B. van; Boeree, M.J.; Soolingen, D. van

2010-01-01

Mycobacterium avium causes lymphadenitis in pigs. This presents an economical burden, as these pigs meat is considered inappropriate for consumption. In humans, lymphadenitis due to nontuberculous mycobacteria (NTM) primarily affects children and is caused by a variety of NTM, though M. avium

Non-tuberculous mycobacteria and microbial populations in drinking water distribution systems

Directory of Open Access Journals (Sweden)

Rossella Briancesco

2010-01-01

Full Text Available Data on the occurrence of non-tuberculous mycobacteria (NTM, in parallel with those obtained for bacterial indicators and amoebae, are presented with the aim to collect information on the spread of NTM in drinking water distribution systems in Italy. Samples were collected from taps of hospitals and households in Central and Southern Italy. The concentration values obtained for the more traditional microbial parameters complied with the mandatory requirements for drinking water. Conversely, moderate-to-high microbial loads (till 300 CFU/L were observed for the NTM. Positive samples were obtained from 62% of the investigated water samples. Analogous results were observed for amoebae showing a higher percentage of positive samples (76%. In terms of public health, the presence of mycobacteria in water distribution systems may represent a potential risk especially for vulnerable people such as children, the elderly or immunocompromised individuals.

Performance Assessment of the CapitalBio Mycobacterium Identification Array System for Identification of Mycobacteria

Science.gov (United States)

Liu, Jingbo; Yan, Zihe; Han, Min; Han, Zhijun; Jin, Lingjie; Zhao, Yanlin

2012-01-01

The CapitalBio Mycobacterium identification microarray system is a rapid system for the detection of Mycobacterium tuberculosis. The performance of this system was assessed with 24 reference strains, 486 Mycobacterium tuberculosis clinical isolates, and 40 clinical samples and then compared to the “gold standard” of DNA sequencing. The CapitalBio Mycobacterium identification microarray system showed highly concordant identification results of 100% and 98.4% for Mycobacterium tuberculosis complex (MTC) and nontuberculous mycobacteria (NTM), respectively. The sensitivity and specificity of the CapitalBio Mycobacterium identification array for identification of Mycobacterium tuberculosis isolates were 99.6% and 100%, respectively, for direct detection and identification of clinical samples, and the overall sensitivity was 52.5%. It was 100% for sputum, 16.7% for pleural fluid, and 10% for bronchoalveolar lavage fluid, respectively. The total assay was completed in 6 h, including DNA extraction, PCR, and hybridization. The results of this study confirm the utility of this system for the rapid identification of mycobacteria and suggest that the CapitalBio Mycobacterium identification array is a molecular diagnostic technique with high sensitivity and specificity that has the capacity to quickly identify most mycobacteria. PMID:22090408

Mycobacterium bovis BCG mycobacteria--new application.

Science.gov (United States)

Kowalewicz-Kulbat, Magdalena; Pestel, Joël; Biet, Franck; Locht, Camille; Tonnel, André-Bernard; Druszczyńska, Magdalena; Rudnicka, Wiesława

2006-01-01

The polarized response of T helper-2 (Th2) lymphocytes to an allergen is considered to be the main cause of the pathogenesis of asthma. In this study, we asked a question whether M. bovis BCG mycobacteria which are known for the preferential stimulation of T helper-1 (Th1) immunity, diminish the effector functions of Th2 cells from allergic patients upon stimulation with a common house dust mite Der p-1 allergen. Our results allow a positive answer to this question. We demonstrate that BCG modulates the dendritic cell-dependent allergen presentation process and switches naive T lymphocytes towards an anti-allergic Th1 profile.

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

International Nuclear Information System (INIS)

Shoemaker, S.A.; Fisher, J.H.; Scoggin, C.H.

1985-01-01

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

MicroRNA-155 promotes autophagy to eliminate intracellular mycobacteria by targeting Rheb.

Science.gov (United States)

Wang, Jinli; Yang, Kun; Zhou, Lin; Minhaowu; Wu, Yongjian; Zhu, Min; Lai, Xiaomin; Chen, Tao; Feng, Lianqiang; Li, Meiyu; Huang, Chunyu; Zhong, Qiu; Huang, Xi

2013-01-01

Mycobacterium tuberculosis is a hard-to-eradicate intracellular pathogen that infects one-third of the global population. It can live within macrophages owning to its ability to arrest phagolysosome biogenesis. Autophagy has recently been identified as an effective way to control the intracellular mycobacteria by enhancing phagosome maturation. In the present study, we demonstrate a novel role of miR-155 in regulating the autophagy-mediated anti-mycobacterial response. Both in vivo and in vitro studies showed that miR-155 expression was significantly enhanced after mycobacterial infection. Forced expression of miR-155 accelerated the autophagic response in macrophages, thus promoting the maturation of mycobacterial phagosomes and decreasing the survival rate of intracellular mycobacteria, while transfection with miR-155 inhibitor increased mycobacterial survival. However, macrophage-mediated mycobacterial phagocytosis was not affected after miR-155 overexpression or inhibition. Furthermore, blocking autophagy with specific inhibitor 3-methyladenine or silencing of autophagy related gene 7 (Atg7) reduced the ability of miR-155 to promote autophagy and mycobacterial elimination. More importantly, our study demonstrated that miR-155 bound to the 3'-untranslated region of Ras homologue enriched in brain (Rheb), a negative regulator of autophagy, accelerated the process of autophagy and sequential killing of intracellular mycobacteria by suppressing Rheb expression. Our results reveal a novel role of miR-155 in regulating autophagy-mediated mycobacterial elimination by targeting Rheb, and provide potential targets for clinical treatment.

MicroRNA-155 promotes autophagy to eliminate intracellular mycobacteria by targeting Rheb.

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Jinli Wang

Full Text Available Mycobacterium tuberculosis is a hard-to-eradicate intracellular pathogen that infects one-third of the global population. It can live within macrophages owning to its ability to arrest phagolysosome biogenesis. Autophagy has recently been identified as an effective way to control the intracellular mycobacteria by enhancing phagosome maturation. In the present study, we demonstrate a novel role of miR-155 in regulating the autophagy-mediated anti-mycobacterial response. Both in vivo and in vitro studies showed that miR-155 expression was significantly enhanced after mycobacterial infection. Forced expression of miR-155 accelerated the autophagic response in macrophages, thus promoting the maturation of mycobacterial phagosomes and decreasing the survival rate of intracellular mycobacteria, while transfection with miR-155 inhibitor increased mycobacterial survival. However, macrophage-mediated mycobacterial phagocytosis was not affected after miR-155 overexpression or inhibition. Furthermore, blocking autophagy with specific inhibitor 3-methyladenine or silencing of autophagy related gene 7 (Atg7 reduced the ability of miR-155 to promote autophagy and mycobacterial elimination. More importantly, our study demonstrated that miR-155 bound to the 3'-untranslated region of Ras homologue enriched in brain (Rheb, a negative regulator of autophagy, accelerated the process of autophagy and sequential killing of intracellular mycobacteria by suppressing Rheb expression. Our results reveal a novel role of miR-155 in regulating autophagy-mediated mycobacterial elimination by targeting Rheb, and provide potential targets for clinical treatment.

Ionizing radiation in the disinfection of water contaminated with potentially pathogenic mycobacteria

International Nuclear Information System (INIS)

Kubin, M.; Sedlackova, J.; Vacek, K.

1982-01-01

Sterile drinking water samples were artificially colonized with M. kansasii, M. gardonae and M. fortuitum suspensions (the numbers of viable units in 1 ml were 1.2x10 3 , 48.5 and 3.2x10 3 , respectively) prepared from mycobacterial strains replicated in Tween 80-free liquid Dubos medium STO. The contaminated water samples were irradiated from a rotary cobalt 60 source (gamma radiation, E=1.17 and 1.33 MeV, dose rate 1 kJ/kg.h at room temperature) with doses 0.7, 1.5, 2.2, 3, 9, 16 and 27 kJ/kg. The disinfecting effectiveness was assessed by direct cultivation tests (0.5 ml volumes of water inoculated on egg medium) and by cultivation on membrane filtres after filtering the whole amount of the water examined (about 500 ml). Total disinfection was recorded for M. kansasii and M. fortuitum irradiated with 9 kJ/kg and for M. gordonae after irradiation with 1.5 kJ/kg. The calculated value of D 10 =0.4 kJ/kg (i.e., the radiation dose that reduces the number of viable mycobacteria by an order of magnitude) is suggestive of a strong disinfecting effect of ionizing radiation on the tested strains of potentially pathogenic mycobacteria. The results indicate that ionizing radiation could be applxcable in disinfecting supply and potable water contaminated with mycobacteria difficult to remove by other methods which, as a rule, cannot ensure permanent disinfection. (author)

Ionizing radiation in the disinfection of water contaminated with potentially pathogenic mycobacteria

Energy Technology Data Exchange (ETDEWEB)

Kubin, M [Institut Hygieny a Epidemiologie, Prague (Czechoslovakia); Sedlackova, J; Vacek, K [Ustav Jaderneho Vyzkumu CSKAE, Rez (Czechoslovakia)

1982-01-01

Sterile drinking water samples were artificially colonized with M. kansasii, M. gardonae and M. fortuitum suspensions (the numbers of viable units in 1 ml were 1.2x10/sup 3/, 48.5 and 3.2x10/sup 3/, respectively) prepared from mycobacterial strains replicated in Tween 80-free liquid Dubos medium STO. The contaminated water samples were irradiated from a rotary cobalt 60 source (gamma radiation, E=1.17 and 1.33 MeV, dose rate 1 kJ/kg.h at room temperature) with doses 0.7, 1.5, 2.2, 3, 9, 16 and 27 kJ/kg. The disinfecting effectiveness was assessed by direct cultivation tests (0.5 ml volumes of water inoculated on egg medium) and by cultivation on membrane filtres after filtering the whole amount of the water examined (about 500 ml). Total disinfection was recorded for M. kansasii and M. fortuitum irradiated with 9 kJ/kg and for M. gordonae after irradiation with 1.5 kJ/kg. The calculated value of D/sub 10/=0.4 kJ/kg (i.e., the radiation dose that reduces the number of viable mycobacteria by an order of magnitude) is suggestive of a strong disinfecting effect of ionizing radiation on the tested strains of potentially pathogenic mycobacteria. The results indicate that ionizing radiation could be applicable in disinfecting supply and potable water contaminated with mycobacteria difficult to remove by other methods which, as a rule, cannot ensure permanent disinfection.

Comparison among three methods for mycobacteria identification Comparación entre tres métodos para identificar micobacterias

OpenAIRE

Misael Mondragón-Barreto; Carlos A. Vázquez-Chacón; Candelaria Barrón-Rivero; Patricia Acosta-Blanco; Kenneth C. Jost Jr; Susana Balandrano; Hiram Olivera-Díaz

2000-01-01

OBJECTIVE: To compare three methods: Biochemical tests, high-performance liquid chromatography (HPLC) and polymerase chain reaction-restriction fragments length polymorphism (PCR-RFLP), for the identification of mycobacteria, and to perform a cost-benefit analysis to define an optimum identification algorithm. MATERIAL AND METHODS: One-hundred-and-seven mycobacteria isolates were identified by the three methods at Instituto de Diagnóstico y Referencia Epidemiológicos, between February of 1999...

Using riboswitches to regulate gene expression and define gene function in mycobacteria.

Science.gov (United States)

Van Vlack, Erik R; Seeliger, Jessica C

2015-01-01

Mycobacteria include both environmental species and many pathogenic species such as Mycobacterium tuberculosis, an intracellular pathogen that is the causative agent of tuberculosis in humans. Inducible gene expression is a powerful tool for examining gene function and essentiality, both in in vitro culture and in host cell infections. The theophylline-inducible artificial riboswitch has recently emerged as an alternative to protein repressor-based systems. The riboswitch is translationally regulated and is combined with a mycobacterial promoter that provides transcriptional control. We here provide methods used by our laboratory to characterize the riboswitch response to theophylline in reporter strains, recombinant organisms containing riboswitch-regulated endogenous genes, and in host cell infections. These protocols should facilitate the application of both existing and novel artificial riboswitches to the exploration of gene function in mycobacteria. © 2015 Elsevier Inc. All rights reserved.

Structural analysis of biofilm formation by rapidly and slowly growing nontuberculous mycobacteria

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Mycobacterium avium complex (MAC) and rapidly growing mycobacteria (RGM) such as M. abscessus, M. mucogenicum, M. chelonae and M. fortuitum, implicated in healthcare-associated infections, are often isolated from potable water supplies as part of the microbial flora. To understa...

Detection and recovery of mycobacteria by a radiometric procedure

International Nuclear Information System (INIS)

Takahashi, H.; Foster, V.

1983-01-01

During a 6-month period, 5,375 clinical specimens were cultured on Middlebrook-Cohn 7H10 medium, on Lowenstein-Jensen medium, and in Middlebrook 7H12 medium containing [ 14 C]palmitic acid. More mycobacteria were recovered when all three media were used than when either the conventional method with 7H10 agar and Lowenstein-Jensen slants or the radiometric method with 7H12 broth was used alone

Methodology of mycobacteria tuberculosis bacteria detection by Raman spectroscopy

Science.gov (United States)

Zyubin, A.; Lavrova, A.; Manicheva, O.; Dogonadze, M.; Tsibulnikova, A.; Samusev, I.

2018-01-01

We have developed a methodology for the study of deactivated strains of Mycobacterium tuberculosis. Strains of the Beijing species obtained from pulmonary patient secrete (XDR strain) and reference strain (H37Rv) were investigated by Raman spectrometry with He-Ne (632,8 nm) laser excitation source. As a result of the research, the optimal experimental parameters have been obtained to get spectra of mycolic acids, which are part of the cell wall of mycobacteria.

Nontuberculous mycobacteria in Denmark, incidence and clinical importance during the last quarter-century

DEFF Research Database (Denmark)

Hermansen, Thomas S; Ravn, Pernille; Svensson, Erik

2017-01-01

and trends in annual incidence rates. 524,119 clinical specimens were cultured for mycobacteria from 1991 through 2015 at the International Reference Laboratory of Mycobacteriology in Denmark. Among these, 8,227 NTM strains were identified from 3,462 patients and distributed according to microbiological...... disease criteria. We observed no increase in NTM disease incidence or proportion of patients with positive NTM cultures during the study period (Quasi-Poisson regression, p = 0.275 and 0.352 respectively). Annual incidence rates were 1.20/105 for definite NTM disease, 0.49/105 for possible NTM disease...... and 0.88/105 for NTM colonization. The incidence rate of NTM disease was highest in children aged 0-4 years (5.36/105/year), predominantly with cervical Mycobacterium avium complex (MAC) adenitis. Surprisingly, based on more than half a million clinical specimens cultured for mycobacteria in Denmark...

Antimicrobial susceptibility testing of rapidly growing mycobacteria by microdilution - Experience of a tertiary care centre

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Set R

2010-01-01

Full Text Available Purpose: The objective of the study was to perform antimicrobial susceptibility testing of rapidly growing mycobacteria (RGM isolated from various clinically suspected cases of extrapulmonary tuberculosis, from January 2007 to April 2008, at a tertiary care centre in Mumbai. Materials and Methods: The specimens were processed for microscopy and culture using the standard procedures. Minimum inhibitory concentrations (MIC were determined by broth microdilution, using Sensititre CA MHBT. Susceptibility testing was also carried out on Mueller Hinton agar by the Kirby Bauer disc diffusion method. Results: Of the 1062 specimens received for mycobacterial cultures, 104 (9.79% grew mycobacteria. Of the mycobacterial isolates, six (5.76% were rapid growers. M. abscessus and M. chelonae appeared to be resistant organisms, with M. chelonae showing intermediate resistance to amikacin and minocycline. However, all the six isolates showed sensitivity to vancomycin and gentamicin by the disc diffusion test. Also all three isolates of M. abscessus were sensitive to piperacillin and erythromycin. Further studies are required to test their sensitivity to these four antimicrobials by using the microbroth dilution test, before they can be prescribed to patients. Conclusions: We wish to emphasize that reporting of rapidly growing mycobacteria from clinical settings, along with their sensitivity patterns, is an absolute need of the hour.

EVALUATION OF THE EFFECT OF SPUTUM STORAGE CONDITIONS ON THE VITAL PROPERTIES OF TUBERCULOUS MYCOBACTERIA

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Yu. D. Rodionova

2017-01-01

Full Text Available Goal of the study: to enhance efficiency of laboratory diagnostics of tuberculous infection through investigating the effect of various storage conditions of samples on the growth properties of Tuberculosis complex mycobacteria.Materials and Methods. 2058 samples of sputum collected by coughing were examined. All sputum samples were aliquoted into 5 parts stored under various conditions: in the fridge under +7°С for 2 hours; frozen for 7 days; by room indoor temperature for 48-72 hours; with the use preservative 10% solution of triple-substituted natrium phosphate for 48 hours; in the fridge under +7°С for 2 hours with consequent treatment by 1% solution of N-acetyl-L-cysteine.Results. The most optimal sputum storage conditions are freezing by -20°С, providing maximum safety of mycobacteria and minimum contamination of the samples with foreign bacteria. Sputum storage by indoor room temperature for 2-3 days reduces the number of positive results of cultures on nutritive media. Using 10% solution of triple-substituted natrium phosphate provides high positive results of bacterioscopic and cultural testing techniques. Time prolongation for biomaterials storage in the preservative solution for more than 72 hours results in the death tuberculous mycobacteria. 

Thiacetazone, an antitubercular drug that inhibits cyclopropanation of cell wall mycolic acids in mycobacteria.

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Anuradha Alahari

2007-12-01

Full Text Available Mycolic acids are a complex mixture of branched, long-chain fatty acids, representing key components of the highly hydrophobic mycobacterial cell wall. Pathogenic mycobacteria carry mycolic acid sub-types that contain cyclopropane rings. Double bonds at specific sites on mycolic acid precursors are modified by the action of cyclopropane mycolic acid synthases (CMASs. The latter belong to a family of S-adenosyl-methionine-dependent methyl transferases, of which several have been well studied in Mycobacterium tuberculosis, namely, MmaA1 through A4, PcaA and CmaA2. Cyclopropanated mycolic acids are key factors participating in cell envelope permeability, host immunomodulation and persistence of M. tuberculosis. While several antitubercular agents inhibit mycolic acid synthesis, to date, the CMASs have not been shown to be drug targets.We have employed various complementary approaches to show that the antitubercular drug, thiacetazone (TAC, and its chemical analogues, inhibit mycolic acid cyclopropanation. Dramatic changes in the content and ratio of mycolic acids in the vaccine strain Mycobacterium bovis BCG, as well as in the related pathogenic species Mycobacterium marinum were observed after treatment with the drugs. Combination of thin layer chromatography, mass spectrometry and Nuclear Magnetic Resonance (NMR analyses of mycolic acids purified from drug-treated mycobacteria showed a significant loss of cyclopropanation in both the alpha- and oxygenated mycolate sub-types. Additionally, High-Resolution Magic Angle Spinning (HR-MAS NMR analyses on whole cells was used to detect cell wall-associated mycolates and to quantify the cyclopropanation status of the cell envelope. Further, overexpression of cmaA2, mmaA2 or pcaA in mycobacteria partially reversed the effects of TAC and its analogue on mycolic acid cyclopropanation, suggesting that the drugs act directly on CMASs.This is a first report on the mechanism of action of TAC, demonstrating the

A low prevalence of mycobacteria in freshwater fish from water reservoirs, ponds and farms

Czech Academy of Sciences Publication Activity Database

Mrlík, V.; Slaný, M.; Kubečka, Jan; Seďa, Jaromír; Nečas, A.; Babák, V.; Slaná, I.; Kříž, P.; Pavlík, I.

2012-01-01

Roč. 35, č. 7 (2012), s. 497-504 ISSN 0140-7775 Institutional support: RVO:60077344 Keywords : food safety * mycobacteriosis * potentially pathogenic mycobacteria * zoonoses Subject RIV: DA - Hydrology ; Limnology Impact factor: 1.591, year: 2012

Occurrence of Opportunistic Pathogens Legionella pneumophila and non-tuberculous mycobacteria in hospital plumbing systems

Science.gov (United States)

Occurrence of Opportunistic Pathogens Legionella pneumophila and non-tuberculous mycobacteria in hospital plumbing systems Jill Hoelle, Michael Coughlin, Elizabeth Sotkiewicz, Jingrang Lu, Stacy Pfaller, Mark Rodgers, and Hodon Ryu U.S. Environmental Protection Agency, Cincinnati...

Nontuberculous mycobacteria in Denmark, incidence and clinical importance during the last quarter-century

DEFF Research Database (Denmark)

Hermansen, Thomas S; Ravn, Pernille; Svensson, Erik

2017-01-01

and trends in annual incidence rates. 524,119 clinical specimens were cultured for mycobacteria from 1991 through 2015 at the International Reference Laboratory of Mycobacteriology in Denmark. Among these, 8,227 NTM strains were identified from 3,462 patients and distributed according to microbiological...... disease criteria. We observed no increase in NTM disease incidence or proportion of patients with positive NTM cultures during the study period (Quasi-Poisson regression, p = 0.275 and 0.352 respectively). Annual incidence rates were 1.20/10(5) for definite NTM disease, 0.49/10(5) for possible NTM disease...... and 0.88/10(5) for NTM colonization. The incidence rate of NTM disease was highest in children aged 0-4 years (5.36/10(5)/year), predominantly with cervical Mycobacterium avium complex (MAC) adenitis. Surprisingly, based on more than half a million clinical specimens cultured for mycobacteria in Denmark...

Subcellular trafficking of mycobacteria: Implications for virulence and immunogenicity

OpenAIRE

Houben, D.

2011-01-01

The aim of this thesis is to determine the properties of the compartment where mycobacteria end up after phagocytosis and which mycobacterial genes play a role in this process. In most cases, bacterial pathogens are taken up by the cell, processed in the endocytic pathway and eventually bacterial derived peptides are presented on MHC class II molecules to CD4+ T-cells. Proteins from viral pathogens in contrast, are degraded in the cytosol and transported into the ER for presentation on MHC cl...

Nontuberculous Mycobacteria Isolation from Clinical and Environmental Samples in Iran: Twenty Years of Surveillance

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Ali Akbar Velayati

2015-01-01

Full Text Available Nontuberculous mycobacteria (NTM are opportunistic pathogens that are widely distributed in the environment. There is a lack of data on species distribution of these organisms from Iran. This study consists of a review of NTM articles published in Iran between the years 1992 and 2014. In this review, 20 articles and 14 case reports were identified. Among the 20 articles, 13 (65% studies focused on NTM isolates from clinical specimens, 6 (30% studies examined NTM isolates from environmental samples, and one (5% article included both clinical and environmental isolates. M. fortuitum (229/997; 23% was recorded as the most prevalent and rapid growing mycobacteria (RGM species in both clinical (28% and environmental (19% isolated samples (P < 0.05. Among slow growing mycobacteria (SGM, M. simiae (103/494; 21% demonstrated a higher frequency in clinical samples whereas in environmental samples it was M. flavescens (44/503; 9%. These data represent information from 14 provinces out of 31 provinces of Iran. No information is available in current published data on clinical or environmental NTM from the remaining 17 provinces in Iran. These results emphasize the potential importance of NTM as well as the underestimation of NTM frequency in Iran. NTM is an important clinical problem associated with significant morbidity and mortality in Iran. Continued research is needed from both clinical and environmental sources to help clinicians and researchers better understand and address NTM treatment and prevention.

Nontuberculous Mycobacteria Isolation from Clinical and Environmental Samples in Iran: Twenty Years of Surveillance.

Science.gov (United States)

Velayati, Ali Akbar; Farnia, Parissa; Mozafari, Mohadese; Mirsaeidi, Mehdi

2015-01-01

Nontuberculous mycobacteria (NTM) are opportunistic pathogens that are widely distributed in the environment. There is a lack of data on species distribution of these organisms from Iran. This study consists of a review of NTM articles published in Iran between the years 1992 and 2014. In this review, 20 articles and 14 case reports were identified. Among the 20 articles, 13 (65%) studies focused on NTM isolates from clinical specimens, 6 (30%) studies examined NTM isolates from environmental samples, and one (5%) article included both clinical and environmental isolates. M. fortuitum (229/997; 23%) was recorded as the most prevalent and rapid growing mycobacteria (RGM) species in both clinical (28%) and environmental (19%) isolated samples (P < 0.05). Among slow growing mycobacteria (SGM), M. simiae (103/494; 21%) demonstrated a higher frequency in clinical samples whereas in environmental samples it was M. flavescens (44/503; 9%). These data represent information from 14 provinces out of 31 provinces of Iran. No information is available in current published data on clinical or environmental NTM from the remaining 17 provinces in Iran. These results emphasize the potential importance of NTM as well as the underestimation of NTM frequency in Iran. NTM is an important clinical problem associated with significant morbidity and mortality in Iran. Continued research is needed from both clinical and environmental sources to help clinicians and researchers better understand and address NTM treatment and prevention.

Pathogenic mycobacteria achieve cellular persistence by inhibiting the Niemann-Pick Type C disease cellular pathway [version 1; referees: 2 approved, 1 approved with reservations

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Paul Fineran

2016-11-01

Full Text Available Background. Tuberculosis remains a major global health concern. The ability to prevent phagosome-lysosome fusion is a key mechanism by which intracellular mycobacteria, including Mycobacterium tuberculosis, achieve long-term persistence within host cells. The mechanisms underpinning this key intracellular pro-survival strategy remain incompletely understood. Host macrophages infected with persistent mycobacteria share phenotypic similarities with cells taken from patients suffering from Niemann-Pick Disease Type C (NPC, a rare lysosomal storage disease in which endocytic trafficking defects and lipid accumulation within the lysosome lead to cell dysfunction and cell death. We investigated whether these shared phenotypes reflected an underlying mechanistic connection between mycobacterial intracellular persistence and the host cell pathway dysfunctional in NPC. Methods. The induction of NPC phenotypes in macrophages from wild-type mice or obtained from healthy human donors was assessed via infection with mycobacteria and subsequent measurement of lipid levels and intracellular calcium homeostasis. The effect of NPC therapeutics on intracellular mycobacterial load was also assessed. Results. Macrophages infected with persistent intracellular mycobacteria phenocopied NPC cells, exhibiting accumulation of multiple lipid types, reduced lysosomal Ca2+ levels, and defects in intracellular trafficking. These NPC phenotypes could also be induced using only lipids/glycomycolates from the mycobacterial cell wall. These data suggest that persistent intracellular mycobacteria inhibit the NPC pathway, likely via inhibition of the NPC1 protein, and subsequently induce altered acidic store Ca2+ homeostasis. Reduced lysosomal calcium levels may provide a mechanistic explanation for the reduced levels of phagosome-lysosome fusion in mycobacterial infection. Treatments capable of correcting defects in NPC mutant cells via modulation of host cell calcium were

Pathogenic mycobacteria achieve cellular persistence by inhibiting the Niemann-Pick Type C disease cellular pathway [version 2; referees: 2 approved, 2 approved with reservations

Directory of Open Access Journals (Sweden)

Paul Fineran

2017-06-01

Full Text Available Background. Tuberculosis remains a major global health concern. The ability to prevent phagosome-lysosome fusion is a key mechanism by which intracellular mycobacteria, including Mycobacterium tuberculosis, achieve long-term persistence within host cells. The mechanisms underpinning this key intracellular pro-survival strategy remain incompletely understood. Host macrophages infected with intracellular mycobacteria share phenotypic similarities with cells taken from patients suffering from Niemann-Pick Disease Type C (NPC, a rare lysosomal storage disease in which endocytic trafficking defects and lipid accumulation within the lysosome lead to cell dysfunction and cell death. We investigated whether these shared phenotypes reflected an underlying mechanistic connection between mycobacterial intracellular persistence and the host cell pathway dysfunctional in NPC.  Methods. The induction of NPC phenotypes in macrophages from wild-type mice or obtained from healthy human donors was assessed via infection with mycobacteria and subsequent measurement of lipid levels and intracellular calcium homeostasis. The effect of NPC therapeutics on intracellular mycobacterial load was also assessed.  Results. Macrophages infected with intracellular mycobacteria phenocopied NPC cells, exhibiting accumulation of multiple lipid types, reduced lysosomal Ca 2+ levels, and defects in intracellular trafficking. These NPC phenotypes could also be induced using only lipids/glycomycolates from the mycobacterial cell wall. These data suggest that intracellular mycobacteria inhibit the NPC pathway, likely via inhibition of the NPC1 protein, and subsequently induce altered acidic store Ca 2+ homeostasis. Reduced lysosomal calcium levels may provide a mechanistic explanation for the reduced levels of phagosome-lysosome fusion in mycobacterial infection. Treatments capable of correcting defects in NPC mutant cells via modulation of host cell calcium were of benefit in

Nontuberculous mycobacteria in Middle East: Current situation and future challenges

OpenAIRE

Velayati, Ali Akbar; Rahideh, Sanaz; Derakhshani Nezhad, Zahra; Farnia, Parissa; Mirsaeidi, Mehdi

2015-01-01

Nontuberculous mycobacteria (NTM) are a diverse group of bacterial species that are distributed in the environment. Many of these environmental bacteria can cause disease in humans. The identification of NTM in environmental sources is important for both clinical and epidemiological purposes. In this study, the distribution of NTM species from environmental and clinical samples in the Middle East was reviewed. In order to provide an overview of NTM, as well as recent epidemiological trends, a...

Engineering more stable, selectable marker-free autoluminescent mycobacteria by one step.

Science.gov (United States)

Yang, Feng; Njire, Moses M; Liu, Jia; Wu, Tian; Wang, Bangxing; Liu, Tianzhou; Cao, Yuanyuan; Liu, Zhiyong; Wan, Junting; Tu, Zhengchao; Tan, Yaoju; Tan, Shouyong; Zhang, Tianyu

2015-01-01

In our previous study, we demonstrated that the use of the autoluminescent Mycobacterium tuberculosis as a reporter strain had the potential to drastically reduce the time, effort, animals and costs consumed in evaluation of the activities of drugs and vaccines in live mice. However, the strains were relatively unstable and lost reporter with time without selection. The kanamycin selection marker used wasn't the best choice as it provides resistance to amino glycosides which are an important class of second line drugs used in tuberculosis treatment. In addition, the marker could limit utility of the strains for screening of new potential drugs or evaluating drug combinations for tuberculosis treatment. Limited selection marker genes for mycobacterial genetic manipulation is a major drawback for such a marker-containing strain in many research fields. Therefore, selectable marker-free, more stable autoluminescent mycobacteria are highly needed. After trying several strategies, we created such mycobacterial strains successfully by using an integrative vector and removing both the resistance maker and integrase genes by Xer site-specific recombination in one step. The corresponding plasmid vectors developed in this study could be very convenient in constructing other selectable marker-free, more stable reporter mycobacteria with diverse applications.

Natural Disasters and Nontuberculous Mycobacteria

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Bernhard, Jon N.; Chan, Edward D.

2015-01-01

Infectious diseases acquired by survivors of large-scale natural disasters complicate the recovery process. During events such as tsunamis, hurricanes, earthquakes, and tornados and well into the recovery period, victims often are exposed to water-soil mixtures that have relocated with indigenous microbes. Because nontuberculous mycobacteria (NTM) are ubiquitous in water and soil, there is potential for increased exposure to these organisms during natural disasters. In this hypothesis-driven commentary, we discuss the rise in NTM lung disease and natural disasters and examine the geographic overlap of NTM infections and disaster frequencies in the United States. Moreover, we show an increased number of positive NTM cultures from Louisiana residents in the years following three of the relatively recent epic hurricanes and posit that such natural disasters may help to drive the increased number of NTM infections. Finally, we advocate for increased environmental studies and surveillance of NTM infections before and after natural disasters. PMID:25644904

High recurrence rate of lymphadenitis due to nontuberculous mycobacteria and its association with concurrent Salmonella infection in Taiwan.

Science.gov (United States)

Hsiao, Cheng-Hsiang; Lai, Chih-Cheng; Hsueh, Po-Ren

2014-06-01

The objective of this study is to investigate the clinical characteristics of lymphadenitis due to nontuberculous mycobacteria (NTM) in Taiwan. We retrospectively reviewed the medical records of all patients who presented to the National Taiwan University Hospital with culture-positive NTM lymphadenitis during the period 2000-2010. Patients with concurrent extranodal involvement were excluded. From 2000 to 2010, 15 patients with lymphadenitis caused by nontuberculous mycobacteria were identified. Most patients (80%, n = 12) were infected with rapidly growing mycobacteria. Mycobacterium abscessus was the most common infective species (n = 8). Recurrence of infection involving multiple organs occurred 2-7 years after the completion of treatment in 11 (73%) patients. Five (33.3%) patients had concurrent Salmonella infections (4 patients with bacteremia and 1 patient with empyema thoracis) during the course of the disease. In Taiwanese patients, we found a high recurrence rate of NTM lymphadenitis that was closely associated with Salmonella infections. We also noted that the clinical and epidemiological manifestations of NTM lymphadenitis in Taiwan differed from their manifestations in western countries. Copyright © 2012. Published by Elsevier B.V.

Cultivable mycobacteria in sphagnum vegetation of moors in South Sweden and coastal Norway.

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Kazda, J; Müller, K; Irgens, L M

1979-04-01

Intact sphagnum vegetation from moors in south Sweden and coastal areas of west Norway contained cultivable mycobacteria in 32% and 30% of the specimens, respectively. This frequency of specimens is lower than the 50% previously found in the partly altered moors of northwestern Germany, but the Scandinavian moors contained a larger variety of species. On both intact and altered moors M. chelonei and M. sphagni sp. nov. were found, the latter a homologous group of 151 strains. In south Sweden the highest frequency was found in S. balticum, S. recurvum. S. tenellum and S. compactum & molle. (40-65%). In coastal Norway the highest frequency was found in S. rubellum (48%) which offers favourable conditions for the accumulation of solar energy due to the red brown colour in the upper parts. Combined with a high humidity in coastal Norway in summer, this may contribute to the growth of mesophilic mycobacteria. A significant affinity of M. chelonei to S. tenellum was stated.

Decolorization of Malachite Green and Crystal Violet by Waterborne Pathogenic Mycobacteria

OpenAIRE

Jones, Jefferson J.; Falkinham III, Joseph O.

2003-01-01

Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium scrofulaceum, Mycobacterium marinum, and Mycobacterium chelonae tolerate high concentrations of the dyes malachite green and crystal violet. Cells of strains of those species decolorized (reduced) both malachite green and crystal violet. Because decolorized malachite green lacked antimicrobial activity, the resistance of these mycobacteria could be due, in part, to their ability to decolorize the dyes. Small amounts of malachite...

Utility of rpoB Gene Sequencing for Identification of Nontuberculous Mycobacteria in the Netherlands

NARCIS (Netherlands)

Zwaan, R. de; Ingen, J. van; Soolingen, D. van

2014-01-01

In the Netherlands, clinical isolation of nontuberculous mycobacteria (NTM) has increased over the past decade. Proper identification of isolates is important, as NTM species differ strongly in clinical relevance. Most of the currently applied identification methods cannot distinguish between all

Molecular epidemiology of nontuberculous mycobacteria isolates from clinical and environmental sources of a metropolitan city.

Directory of Open Access Journals (Sweden)

Ali Akbar Velayati

Full Text Available While NTM infection is mainly acquired from environmental exposure, monitoring of environmental niches for NTM is not a routine practice. This study aimed to find the prevalence of environmental NTM in soil and water in four highly populated suburbs of Tehran, Iran.A total of 4014 samples from soil and water resources were collected and studied. Sediments of each treated sample were cultured in Lowenstein-Jensen medium and observed twice per week for growth rate, colony morphology, and pigmentation. Colonies were studied with phenotypic tests. Molecular analysis was performed on single colonies derived from subculture of original isolates. Environmental samples were compared with 34 NTM isolates from patients who were residents of the study locations.Out of 4014 samples, mycobacteria were isolated from 862 (21.4% specimens; 536 (62.1% belonged to slow growing mycobacteria (SGM and 326 (37.8% were rapid growing mycobacteria (RGM. The five most frequent NTM were M. farcinogens (105/862; 12.1%, M. fortuitum (72/862; 8.3%, M. senegalense (58/862; 6.7%, M. kansasii (54/862; 6.2%, and M. simiae (46/862; 5.3%. In total, 62.5% (539/862 of mycobacterial positive samples were isolated from water and only 37.4% (323/862 of them were isolated from soil samples (P<0.05. Out of 5314 positive clinical samples for mycobacteria, 175 (3.2% isolates were NTM. The trend of NTM isolates increased from 1.2% (13 out of 1078 in 2004 to 3.8% (39 out of 1005 in 2014 (P = 0.0001. The major clinical isolates were M. simiae (51; 29.1%, M. kansasii (26; 14.8%, M. chelonae (28; 16%, and M. fortuitum (13; 7.4%.Comparing the distribution pattern of environmental NTM isolates with clinical isolates suggests a possible transmission link, but this does not apply to all environmental NTM species. Our study confirms an increasing trend of NTM isolation from clinical samples that needs further investigation.

Verification of Frequency in Species of Nontuberculous Mycobacteria in Kermanshah Drinking Water Supplies Using the PCR-Sequencing Method.

Science.gov (United States)

Mohajeri, Parviz; Yazdani, Laya; Shahraki, Abdolrazagh Hashemi; Alvandi, Amirhoshang; Atashi, Sara; Farahani, Abbas; Almasi, Ali; Rezaei, Mansour

2017-04-01

Nontuberculous mycobacteria are habitants of environment, especially in aquatic systems. Some of them cause problems in immunodeficient patients. Over the last decade, 16S rRNA gene sequencing was established in 45 novel species of nontuberculous mycobacteria. Experiences revealed that this method underestimates the diversity, but does not distinguish between some of mycobacterium subsp. To recognize emerging rapidly growing mycobacteria and identify their subsp, rpoB gene sequencing has been developed. To better understand the transmission of nontuberculous mycobacterial species from drinking water and preventing the spread of illness with these bacteria, the aim of this study was to detect the presence of bacteria by PCR-sequencing techniques. Drinking water samples were collected from different areas of Kermanshah city in west of IRAN. After decontamination with cetylpyridinium chloride, samples were filtered with 0.45-micron filters, the filter transferred directly on growth medium waiting to appear in colonies, then DNA extraction and PCR were performed, and products were sent to sequencing. We found 35/110 (32%) nontuberculous mycobacterial species in drinking water samples, isolates included Mycobacterium goodii, Mycobacterium aurum, and Mycobacterium gastri with the most abundance (11.5%), followed by Mycobacterium smegmatis, Mycobacterium porcinum, Mycobacterium peregrinum, Mycobacterium mucogenicum, and Mycobacterium chelonae (8%). In this study, we recognized the evidence of contamination by nontuberculous mycobacteria in corroded water pipes. As a result of the high prevalence of these bacteria in drinking water in Kermanshah, this is important evidence of transmission through drinking water. This finding can also help public health policy makers control these isolates in drinking water supplies in Kermanshah.

Hypersensitivity of hypoxia grown Mycobacterium smegmatis to DNA damaging agents: implications of the DNA repair deficiencies in attenuation of mycobacteria.

Science.gov (United States)

Rex, Kervin; Kurthkoti, Krishna; Varshney, Umesh

2013-10-01

Mycobacteria are an important group of pathogenic bacteria. We generated a series of DNA repair deficient strains of Mycobacterium smegmatis, a model organism, to understand the importance of various DNA repair proteins (UvrB, Ung, UdgB, MutY and Fpg) in survival of the pathogenic strains. Here, we compared tolerance of the M. smegmatis strains to genotoxic stress (ROS and RNI) under aerobic, hypoxic and recovery conditions of growth by monitoring their survival. We show an increased susceptibility of mycobacteria to genotoxic stress under hypoxia. UvrB deficiency led to high susceptibility of M. smegmatis to the DNA damaging agents. Ung was second in importance in strains with single deficiencies. Interestingly, we observed that while deficiency of UdgB had only a minor impact on the strain's susceptibility, its combination with Ung deficiency resulted in severe consequences on the strain's survival under genotoxic stress suggesting a strong interdependence of different DNA repair pathways in safeguarding genomic integrity. Our observations reinforce the possibility of targeting DNA repair processes in mycobacteria for therapeutic intervention during active growth and latency phase of the pathogen. High susceptibility of the UvrB, or the Ung/UdgB deficient strains to genotoxic stress may be exploited in generation of attenuated strains of mycobacteria. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Surveillance of Tuberculosis in Taipei: The Influence of Nontuberculous Mycobacteria

OpenAIRE

Chiang, Chen-Yuan; Yu, Ming-Chih; Yang, Shiang-Lin; Yen, Muh-Yong; Bai, Kuan-Jen

2015-01-01

Background Notification of tuberculosis (TB) but not nontuberculous mycobacteria (NTM) is mandatory in Taiwan. Partly due to the strict regulation on TB notification, several patients infected with NTM were notified as TB cases. Notification of patients infected with NTM as TB cases can trigger public health actions and impose additional burdens on the public health system. We conducted a study to assess the influence of NTM infection on surveillance of TB in Taipei. Methodology/Principal Fin...

Interleukin-1 or tumor necrosis factor-alpha augmented the cytotoxic effect of mycobacteria on human fibroblasts: application to evaluation of pathogenesis of clinical isolates of Mycobacterium tuberculosis and M. avium complex.

Science.gov (United States)

Takii, T; Abe, C; Tamura, A; Ramayah, S; Belisle, J T; Brennan, P J; Onozaki, K

2001-03-01

Mycobacteria-induced in vitro events reflecting human tuberculosis can contribute to the evaluation of the pathogenesis of Mycobacterium tuberculosis (MTB). In this study, we propose such an in vitro method based on live mycobacteria-induced cytotoxicity to human cell lines. When human lung-derived normal fibroblast cell line MRC-5 was infected with various strains of mycobacteria (M. tuberculosis H(37)Rv and H(37) Ra, Mycobacterium avium 427S and 2151SmO, and Mycobacterium bovis BCG Pasteur and Tokyo), the fibroblasts were killed by mycobacteria according to the degree of virulence. Other human originated macrophage (U-937, THP-1), myeloid (HL-60), and epithelial carcinoma (A549) cell lines exhibited a similar cytotoxic response to virulent mycobacteria. MRC-5 was most susceptible to virulent mycobacteria among various human cell lines examined. The cytotoxicity was enhanced by the proinflammatory cytokines, interleukin-1 (IL-1) and tumor necrosis factor-a (TNF-alpha), which in the absence of mycobacteria stimulate the growth of normal human fibroblasts. This in vitro evaluation system was applied to clinical isolates of drug-sensitive MTB (DS-MTB), drug-resistant MTB (DR-MTB) including multidrug-resistant (MDR-MTB), and M. avium complex (MAC). MTB strains (n = 24) exhibited strong cytotoxic activity, but MAC strains (n = 5) had only weak activity. Furthermore, there was no significant difference in cytotoxicity between DS-MTB (n = 11) and DR-MTB (n = 13). Collectively, these results suggest that this new in vitro system is useful for evaluating the pathogenesis of mycobacteria and that there was no difference in the pathogenesis between drug-susceptible and drug-resistant clinical isolates.

Destruction of Various Kinds of Mycobacteria in Milk by Pasteurization

Science.gov (United States)

Harrington, Rube; Karlson, Alfred G.

1965-01-01

Various strains of unclassified mycobacteria, Mycobacterium tuberculosis (including H37Rv strains), M. bovis, M. avium, M. fortuitum, and bacille Calmette-Guerin, were exposed to the temperature and time of pasteurization in skim milk in test tubes. Of the 195 strains tested, there were a few surviving colonies among 6 of 33 skotochromogens, 1 of 26 photochromogens, 10 of 79 nonchromogens, and 1 of 9 rapid growers. Subcultures of the surviving colonies failed to resist the pasteurization tests on subsequent trials. PMID:14325295

Engineering more stable, selectable marker-free autoluminescent mycobacteria by one step.

Directory of Open Access Journals (Sweden)

Feng Yang

Full Text Available In our previous study, we demonstrated that the use of the autoluminescent Mycobacterium tuberculosis as a reporter strain had the potential to drastically reduce the time, effort, animals and costs consumed in evaluation of the activities of drugs and vaccines in live mice. However, the strains were relatively unstable and lost reporter with time without selection. The kanamycin selection marker used wasn't the best choice as it provides resistance to amino glycosides which are an important class of second line drugs used in tuberculosis treatment. In addition, the marker could limit utility of the strains for screening of new potential drugs or evaluating drug combinations for tuberculosis treatment. Limited selection marker genes for mycobacterial genetic manipulation is a major drawback for such a marker-containing strain in many research fields. Therefore, selectable marker-free, more stable autoluminescent mycobacteria are highly needed. After trying several strategies, we created such mycobacterial strains successfully by using an integrative vector and removing both the resistance maker and integrase genes by Xer site-specific recombination in one step. The corresponding plasmid vectors developed in this study could be very convenient in constructing other selectable marker-free, more stable reporter mycobacteria with diverse applications.

Distribution of nontuberculous mycobacteria in treated patients with pulmonary disease in Greece - relation to microbiological data.

Science.gov (United States)

Manika, Katerina; Tsikrika, Stamatoula; Tsaroucha, Emilia; Karabela, Simona; Karachaliou, Iris; Bosmi, Ioulia; Kioumis, Ioannis; Papavasileiou, Apostolos

2015-01-01

The aim was to assess the distribution of nontuberculous mycobacteria (NTM) in treated patients with pulmonary disease (PD) in Greece. Patients treated for NTM PD at the two largest chest diseases hospitals in Greece, in the period 1990-2013 were investigated. For the years 2005-2013 data on NTM isolation frequency were recorded. M. avium complex (MAC) was the predominant cause of NTM PD disease followed by M. kansasii and rapid growing mycobacteria (RGM). The pathogenicity of RGM was significantly lower than this of MAC and M. kansasii. An increase was observed in the percentage of isolated NTM species that were considered clinically significant over the study period. The increasing number of NTM PD in Greece is a consequence of their isolation being more frequently considered as clinically relevant.

Recent advances on nontuberculous mycobacteria diseases in Asia

Directory of Open Access Journals (Sweden)

Po-Ren Hsueh

2015-01-01

Full Text Available The isolation rate of nontuberculous mycobacteria (NTM species and the prevalence of NTM-associated diseases are on the rise worldwide; however, the species distribution of NTM isolates and the types of diseases caused by NTM species vary from region to region. Treatment of a NTM disease is complicated, and there is no comprehensive guideline regarding the in vitro susceptibility of each antimicrobial agent against NTM. Therefore, appropriate anti-NTM treatment can only be recommended based on individual NTM species and local surveillance studies of anti-NTM resistance. Previous studies on the in vitro susceptibility of Mycobacterium avium complex (MAC to clarithromycin in some Asian countries have revealed a low rate of resistance to that antimicrobial agent. Thus, a clarithromycin-based anti-MAC regimen should be effective for MAC infections. However, clarithromycin resistance due to the mutation of the 23S rRNA gene in MAC strains has been detected in many countries. Therefore, physicians should avoid monotherapy with clarithromycin and consider the possibility of clarithromycin resistance in patients who do not respond to clarithromycin-based regimens. Rifampicin is the critical component of successful management of Mycobacterium kansasii diseases. Although most M. kansasii isolates are susceptible to rifampicin in Western countries and in Japan, this agent may not work well in Taiwan. Rapidly growing mycobacteria (RGM is a prevalent NTM group worldwide, particularly in Asia; however, each NTM species in this group may have its own distinct antibiotic susceptibility pattern, and close monitoring of the antibiotic-resistance patterns of RGM is necessary. Most important of all, the in vitro susceptibility may not represent the in vivo activity until the confirmation of the clinical study. Therefore, further investigation of the clinical effectiveness of the anti-NTM agents is warranted.

The geographic diversity of nontuberculous mycobacteria isolated from pulmonary samples: an NTM-NET collaborative study

NARCIS (Netherlands)

Hoefsloot, W.; Ingen, J. van; Andrejak, C.; Angeby, K.; Bauriaud, R.; Bemer, P.; Beylis, N.; Boeree, M.J.; Cacho, J.; Chihota, V.; Chimara, E.; Churchyard, G.; Cias, R.; Daza, R.; Daley, C.L.; Dekhuijzen, P.N.R.; Domingo, D.; Drobniewski, F.; Esteban, J. De; Fauville-Dufaux, M.; Folkvardsen, D.B.; Gibbons, N.; Gomez-Mampaso, E.; Gonzalez, R.; Hoffmann, H.; Hsueh, P.R.; Indra, A.; Jagielski, T.; Jamieson, F.; Jankovic, M.; Jong, E. de; Keane, J.; Koh, W.J.; Lange, B. de; Leao, S.; Macedo, R.; Mannsaker, T.; Marras, T.K.; Maugein, J.; Milburn, H.J.; Mlinko, T.; Morcillo, N.; Morimoto, K.; Papaventsis, D.; Palenque, E.; Paez-Pena, M.; Piersimoni, C.; Polanova, M.; Rastogi, N.; Richter, E.; Ruiz-Serrano, M.J.; Silva, A.; Silva, M.P. da; Simsek, H.; Soolingen, D. van; Szabo, N.; Thomson, R.; Fernandez, T. Tortola; Tortoli, E.; Totten, S.E.; Tyrrell, G.; Vasankari, T.; Villar, M.; Walkiewicz, R.; Winthrop, K.L.; Wagner, D.; Trials, G. Nontuberculous

2013-01-01

A significant knowledge gap exists concerning the geographical distribution of nontuberculous mycobacteria (NTM) isolation worldwide. To provide a snapshot of NTM species distribution, global partners in the NTM-Network European Trials Group (NET) framework (www.ntm-net.org), a branch of the

COMPARATIVE ANALYSIS OF METHODS FOR IDENTIFICATION OF NONTUBERCULOUS MYCOBACTERIA ISOLATED FROM CLINICAL MATERIAL

Directory of Open Access Journals (Sweden)

A. V. Lyamin

2017-01-01

-ToF spectrometry, DNA hybridization were not determined to species. 17 (21.8% of microbial strains which have been identified using the method of DNA hybridization, identified by spectrometry, including slow-growing microorganisms, non-mycobacteria strains seven (9.0%: Gordonia rubriperticta, Nocardia forcinica, Tsukumurella spp., Rhodotorula mucilaginosa. Accurate species identification NTMB is fundamental to determine the tactics of treatment of patients with mycobacteriosis. Due to this rather limited possibility of identification of non-tuberculous mycobacteria, using a DNA-hybridization method is inadequate to date. The introduction of new techniques, such as MALDI-ToF spectrometry, can identify a greater number of species of nontuberculous mycobacteria, as well as other types of slow-growing microorganisms having similarities with mycobacteria on cultural and morphological properties, which significantly increases the diagnostic capabilities of laboratories.

Molecular epidemiology of nontuberculous mycobacteria isolates from clinical and environmental sources of a metropolitan city.

Science.gov (United States)

Velayati, Ali Akbar; Farnia, Parissa; Mozafari, Mohadese; Malekshahian, Donya; Seif, Shima; Rahideh, Snaz; Mirsaeidi, Mehdi

2014-01-01

While NTM infection is mainly acquired from environmental exposure, monitoring of environmental niches for NTM is not a routine practice. This study aimed to find the prevalence of environmental NTM in soil and water in four highly populated suburbs of Tehran, Iran. A total of 4014 samples from soil and water resources were collected and studied. Sediments of each treated sample were cultured in Lowenstein-Jensen medium and observed twice per week for growth rate, colony morphology, and pigmentation. Colonies were studied with phenotypic tests. Molecular analysis was performed on single colonies derived from subculture of original isolates. Environmental samples were compared with 34 NTM isolates from patients who were residents of the study locations. Out of 4014 samples, mycobacteria were isolated from 862 (21.4%) specimens; 536 (62.1%) belonged to slow growing mycobacteria (SGM) and 326 (37.8%) were rapid growing mycobacteria (RGM). The five most frequent NTM were M. farcinogens (105/862; 12.1%), M. fortuitum (72/862; 8.3%), M. senegalense (58/862; 6.7%), M. kansasii (54/862; 6.2%), and M. simiae (46/862; 5.3%). In total, 62.5% (539/862) of mycobacterial positive samples were isolated from water and only 37.4% (323/862) of them were isolated from soil samples (Pdistribution pattern of environmental NTM isolates with clinical isolates suggests a possible transmission link, but this does not apply to all environmental NTM species. Our study confirms an increasing trend of NTM isolation from clinical samples that needs further investigation.

The tracing of mycobacteria in drinking water supply systems by culture, conventional, and real time PCRs

Czech Academy of Sciences Publication Activity Database

Klanicová, B.; Seďa, Jaromír; Slaná, I.; Slaný, M.; Pavlík, I.

2013-01-01

Roč. 67, č. 6 (2013), s. 725-731 ISSN 0343-8651 Institutional support: RVO:60077344 Keywords : avium subsp paratuberculosis * nontuberculous mycobacteria * potable water * survival * intracellulare Subject RIV: EE - Microbiology, Virology Impact factor: 1.359, year: 2013

Lipoproteins of slow-growing Mycobacteria carry three fatty acids and are N-acylated by apolipoprotein N-acyltransferase BCG_2070c.

Science.gov (United States)

Brülle, Juliane K; Tschumi, Andreas; Sander, Peter

2013-10-05

Lipoproteins are virulence factors of Mycobacterium tuberculosis. Bacterial lipoproteins are modified by the consecutive action of preprolipoprotein diacylglyceryl transferase (Lgt), prolipoprotein signal peptidase (LspA) and apolipoprotein N- acyltransferase (Lnt) leading to the formation of mature triacylated lipoproteins. Lnt homologues are found in Gram-negative and high GC-rich Gram-positive, but not in low GC-rich Gram-positive bacteria, although N-acylation is observed. In fast-growing Mycobacterium smegmatis, the molecular structure of the lipid modification of lipoproteins was resolved recently as a diacylglyceryl residue carrying ester-bound palmitic acid and ester-bound tuberculostearic acid and an additional amide-bound palmitic acid. We exploit the vaccine strain Mycobacterium bovis BCG as model organism to investigate lipoprotein modifications in slow-growing mycobacteria. Using Escherichia coli Lnt as a query in BLASTp search, we identified BCG_2070c and BCG_2279c as putative lnt genes in M. bovis BCG. Lipoproteins LprF, LpqH, LpqL and LppX were expressed in M. bovis BCG and BCG_2070c lnt knock-out mutant and lipid modifications were analyzed at molecular level by matrix-assisted laser desorption ionization time-of-flight/time-of-flight analysis. Lipoprotein N-acylation was observed in wildtype but not in BCG_2070c mutants. Lipoprotein N- acylation with palmitoyl and tuberculostearyl residues was observed. Lipoproteins are triacylated in slow-growing mycobacteria. BCG_2070c encodes a functional Lnt in M. bovis BCG. We identified mycobacteria-specific tuberculostearic acid as further substrate for N-acylation in slow-growing mycobacteria.

Comparison of a radiometric method (BACTEC) and conventional culture media for recovery of mycobacteria from smear-negative specimens

International Nuclear Information System (INIS)

Morgan, M.A.; Horstmeier, C.D.; DeYoung, D.R.; Roberts, G.D.

1983-01-01

The BACTEC system and three conventional media (Middlebrook 7H10, selective Middlebrook 7H11 [S7H11], and Lowenstein-Jensen [LJ] were compared for their mean recovery times and recovery rates of mycobacteria from acid-fast, smear-negative clinical specimens. Of the 71 smear-negative, culture-positive specimens recovered from 2,165 submitted smear-negative cultures, the BACTEC system detected 71.8%, compared with 88.7% for the conventional three-medium system. When media were individually compared, BACTEC medium (Middlebrook 7H12) was more successful in recovering mycobacteria (71.8%) than was LJ (62%), Middlebrook medium 7H10 (55.9%), or Middlebrook S7H11 medium (52.1%). Middlebrook 7H11 medium containing sodium selenate was also evaluated and did not increase the recovery rate or decrease the recovery time of mycobacterial species when compared with LJ, Middlebrook 7H10, S7H11, and 7H12 media. The mean detection time for the BACTEC system was less than that by conventional methods for the seven species of mycobacteria recovered. Detection times for Mycobacterium tuberculosis on the BACTEC system and conventional cultural systems were 13.7 and 26.3 days, respectively

Analysis of recombinant mycobacteria as T helper type 1 vanccines in an allergy challange model

NARCIS (Netherlands)

Janssen, R.; Kruisselbrink, A.; Hoogteyling, L.; Lamb, J.R.; Young, D.B.; Thole, J.E.R.

2001-01-01

The potential for development of mycobacteria as T helper type 1 (Th1) vaccines capable of induction of Th1 responses to recombinant antigens was explored in a model system based on an immunodominant peptide from house dust mite. Different recombinant mycobacterial preparations were compared for

Synthesis of avibactam derivatives and activity on β-lactamases and peptidoglycan biosynthesis enzymes of mycobacteria.

Science.gov (United States)

Edoo, Zainab; Iannazzo, Laura; Compain, Fabrice; Li de la Sierra Gallay, Inès; van Tilbeurgh, Herman; Fonvielle, Matthieu; Bouchet, Flavie; Le Run, Eva; Mainardi, Jean-Luc; Arthur, Michel; Ethève-Quelquejeu, Mélanie; Hugonnet, Jean-Emmanuel

2018-03-30

There is a renewed interest for β-lactams for treating infections due to Mycobacterium tuberculosis and M. abscessus since their β-lactamases are inhibited by classical (clavulanate) or new generation (avibactam) inhibitors, respectively. Here, we report access to an azido derivative of the diazabicyclooctane (DBO) scaffold of avibactam for functionalization by the Huisgen-Sharpless cycloaddition reaction. The amoxicillin-DBO combinations were active indicating that the triazole ring is compatible with drug penetration (minimal inhibitory concentration of 16 µg/ml for both species). Mechanistically, β-lactamase inhibition was not sufficient to account for the potentiation of amoxicillin by DBOs. Thus, we investigated the latter compounds as inhibitors of L,D-transpeptidases (LDTs), which are the main peptidoglycan polymerases in mycobacteria. The DBOs acted as slow-binding inhibitors of LDTs by S-carbamoylation indicating that optimization of DBOs for LDT inhibition is an attractive strategy to obtain drugs selectively active on mycobacteria. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pathogenesis of tuberculosis and other mycobacteriosis.

Science.gov (United States)

Cardona, Pere-Joan

2018-01-01

The evolution between Mycobacterium tuberculosis infection and active tuberculosis is multifactorial and involves different biological scales. The synthesis of ESAT-6 or the induction of alveolar macrophage necrosis are key, but to understand it, it is necessary to consider the dynamics of endogenous and exogenous reinfection, drainage of lung parenchyma and respiratory mechanics, local fibrosis processes and blood supply. Paradoxically, the immune response generated by the infection is highly protective (90%) against active tuberculosis, although as it is essentially based on the proliferation of Th1 lymphocytes, it cannot prevent reinfection. Severe immunosuppression can only explain 10% of active tuberculosis cases, while the remainder are attributable to comorbidities, a proinflammatory environment and an unknown genetic propensity. The pathogenic capacity of environmental mycobacteria is discrete, linked to deficits in the innate and acquired immune response. The ability to generate biofilms and the ability of M. ulcerans to generate the exotoxin mycolactone is remarkable. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Developing whole mycobacteria cell vaccines for tuberculosis: Workshop proceedings, Max Planck Institute for Infection Biology, Berlin, Germany, July 9, 2014.

Science.gov (United States)

2015-06-12

On July 9, 2014, Aeras and the Max Planck Institute for Infection Biology convened a workshop entitled "Whole Mycobacteria Cell Vaccines for Tuberculosis" at the Max Planck Institute for Infection Biology on the grounds of the Charité Hospital in Berlin, Germany, close to the laboratory where, in 1882, Robert Koch first identified Mycobacterium tuberculosis (Mtb) as the pathogen responsible for tuberculosis (TB). The purpose of the meeting was to discuss progress in the development of TB vaccines based on whole mycobacteria cells. Live whole cell TB vaccines discussed at this meeting were derived from Mtb itself, from Bacille Calmette-Guérin (BCG), the only licensed vaccine against TB, which was genetically modified to reduce pathogenicity and increase immunogenicity, or from commensal non-tuberculous mycobacteria. Inactivated whole cell TB and non-tuberculous mycobacterial vaccines, intended as immunotherapy or as safer immunization alternatives for HIV+ individuals, also were discussed. Workshop participants agreed that TB vaccine development is significantly hampered by imperfect animal models, unknown immune correlates of protection and the absence of a human challenge model. Although a more effective TB vaccine is needed to replace or enhance the limited effectiveness of BCG in all age groups, members of the workshop concurred that an effective vaccine would have the greatest impact on TB control when administered to adolescents and adults, and that use of whole mycobacteria cells as TB vaccine candidates merits greater support, particularly given the limited understanding of the specific Mtb antigens necessary to generate an immune response capable of preventing Mtb infection and/or disease. Copyright © 2015. Published by Elsevier Ltd.. All rights reserved.

Clinical and Taxonomic Status of Pathogenic Nonpigmented or Late-Pigmenting Rapidly Growing Mycobacteria

OpenAIRE

Brown-Elliott, Barbara A.; Wallace, Richard J.

2002-01-01

The history, taxonomy, geographic distribution, clinical disease, and therapy of the pathogenic nonpigmented or late-pigmenting rapidly growing mycobacteria (RGM) are reviewed. Community-acquired disease and health care-associated disease are highlighted for each species. The latter grouping includes health care-associated outbreaks and pseudo-outbreaks as well as sporadic disease cases. Treatment recommendations for each species and type of disease are also described. Special emphasis is on ...

Azurophil granule proteins constitute the major mycobactericidal proteins in human neutrophils and enhance the killing of mycobacteria in macrophages

DEFF Research Database (Denmark)

Jena, Prajna; Mohanty, Soumitra; Mohanty, Tirthankar

2012-01-01

Pathogenic mycobacteria reside in, and are in turn controlled by, macrophages. However, emerging data suggest that neutrophils also play a critical role in innate immunity to tuberculosis, presumably by their different antibacterial granule proteins. In this study, we purified neutrophil azurophil...... and specific granules and systematically analyzed the antimycobacterial activity of some purified azurophil and specific granule proteins against M. smegmatis, M. bovis-BCG and M. tuberculosis H37Rv. Using gel overlay and colony forming unit assays we showed that the defensin-depleted azurophil granule...... proteins (AZP) were more active against mycobacteria compared to other granule proteins and cytosolic proteins. The proteins showing antimycobacterial activity were identified by MALDI-TOF mass spectrometry. Electron microscopic studies demonstrate that the AZP disintegrate bacterial cell membrane...

Identification of a Novel Conjugative Plasmid in Mycobacteria That Requires Both Type IV and Type VII Secretion

KAUST Repository

Ummels, R.; Abdallah, A. M.; Kuiper, V.; Aajoud, A.; Sparrius, M.; Naeem, R.; Spaink, H. P.; van Soolingen, D.; Pain, Arnab; Bitter, W.

2014-01-01

Conjugative plasmids play an important role in horizontal gene transfer between different bacteria and, as such, in their adaptation and evolution. This effect is most obvious in the spread of antibiotic resistance genes. Thus far, conjugation of natural plasmids has been described only rarely for mycobacterial species. In fact, it is generally accepted that M. tuberculosis does not show any recent sign of horizontal gene transfer. In this study, we describe the identification of a new widespread conjugative plasmid that can also be efficiently transferred to M. tuberculosis. This plasmid therefore poses both a threat and an opportunity. The threat is that, through the acquisition of antibiotic resistance markers, this plasmid could start a rapid spread of antibiotic resistance genes between pathogenic mycobacteria. The opportunity is that we could use this plasmid to generate new tools for the efficient introduction of foreign DNA in slow-growing mycobacteria.

Blending genomes: distributive conjugal transfer in mycobacteria, a sexier form of HGT.

Science.gov (United States)

Gray, Todd A; Derbyshire, Keith M

2018-04-18

This review discusses a novel form of horizontal gene transfer (HGT) found in mycobacteria called Distributive Conjugal Transfer (DCT). While satisfying the criteria for conjugation, DCT occurs by a mechanism so distinct from oriT-mediated conjugation that it could be considered a fourth category of HGT. DCT involves the transfer of chromosomal DNA between mycobacteria and, most significantly, generates transconjugants with mosaic genomes of the parental strains. Multiple segments of donor chromosomal DNA can be co-transferred regardless of their location or the genetic selection and, as a result, the transconjugant genome contains many donor-derived segments; hence the name DCT. This distinguishing feature of DCT separates it from the other known mechanisms of HGT, which generally result in the introduction of a single, defined segment of DNA into the recipient chromosome (Fig. ). Moreover, these mosaic progeny are generated from a single conjugal event, which provides enormous capacity for rapid adaptation and evolution, again distinguishing it from the three classical modes of HGT. Unsurprisingly, the unusual mosaic products of DCT are generated by a conjugal mechanism that is also unusual. Here, we will describe the unique features of DCT and contrast those to other mechanisms of HGT, both from a mechanistic and an evolutionary perspective. Our focus will be on transfer of chromosomal DNA, as opposed to plasmid mobilization, because DCT mediates transfer of chromosomal DNA and is a chromosomally encoded process. © 2018 John Wiley & Sons Ltd.

MicroRNAs play big roles in modulating macrophages response toward mycobacteria infection.

Science.gov (United States)

Abdalla, Abualgasim Elgaili; Duan, Xiangke; Deng, Wanyan; Zeng, Jie; Xie, Jianping

2016-11-01

Macrophages are crucial player in the defense against multiple intracellular pathogens. Mycobacterium tuberculosis, the causative agent of tuberculosis which inflicted around one third of global population, can replicate and persist within macrophages. MicroRNAs, endogenous, small noncoding RNA, can regulate the expression of macrophages genes required for appropriate signaling. Mycobacteria can manipulate the expression of macrophages microRNAs to subvert cell response for its survival and persistence. This review summarized the progress of microRNAs in mycobacterial pathogenesis. Copyright © 2016 Elsevier B.V. All rights reserved.

Rapidly growing non-tuberculous mycobacteria infection of prosthetic knee joints: A report of two cases.

Science.gov (United States)

Kim, Manyoung; Ha, Chul-Won; Jang, Jae Won; Park, Yong-Beom

2017-08-01

Non-tuberculous mycobacteria (NTM) cause prosthetic knee joint infections in rare cases. Infections with rapidly growing non-tuberculous mycobacteria (RGNTM) are difficult to treat due to their aggressive clinical behavior and resistance to antibiotics. Infections of a prosthetic knee joint by RGNTM have rarely been reported. A standard of treatment has not yet been established because of the rarity of the condition. In previous reports, diagnoses of RGNTM infections in prosthetic knee joints took a long time to reach because the condition was not suspected, due to its rarity. In addition, it is difficult to identify RGNTM in the lab because special identification tests are needed. In previous reports, after treatment for RGNTM prosthetic infections, knee prostheses could not be re-implanted in all cases but one, resulting in arthrodesis or resection arthroplasty; this was most likely due to the aggressiveness of these organisms. In the present report, two cases of prosthetic knee joint infection caused by RGNTM (Mycobacterium abscessus) are described that were successfully treated, and in which prosthetic joints were finally reimplanted in two-stage revision surgery. Copyright © 2017 Elsevier B.V. All rights reserved.

ANALYSIS OF MUTATIONS OF TUBERCULOUS MYCOBACTERIA DEFINING DRUG RESISTANCE IN HIV POSITIVE AND HIV NEGATIVE TUBERCULOSIS PATIENTS WITHOUT PRIOR HISTORY OF TREATMENT IN SVERDLOVSK REGION

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G. V. Panov

2017-01-01

Full Text Available Goal of the study: to identify profile of mutations of tuberculous mycobacteria responsible for resistance to anti-tuberculosis drugs in HIV positive and HIV negative tuberculosis patients without prior history of treatment.Materials and methods. 165 strains of tuberculous mycobacteria from HIV positive patients and 166 strains of tuberculous mycobacteria from HIV negative patients were studied in Sverdlovsk Region (TB Dispensary, Yekaterinburg. Mutations in genes were identified using microchips of TB-BIOCHIP® and TB-BIOCHIP®-2 in compliance with the manufacturer's guidelines (OOO Biochip-IMB, Moscow.Results. It was observed that 85/165 (51.52% strains isolated from HIV positive tuberculosis patients and 58/166 (34.94% strains isolated from tuberculosis patients not associated with HIV possessed MDR genotype (p < 0.01. The majority of MDR strains had mutations in the 531th codon of rpoB (Ser→Leu and 315th codon of katG (Ser→Thr (64/85, 75.29% and 38/58, 65.52% respective the groups, resulting in the high level of resistance to rifampicin and isoniazid. Each group also had approximately equal ratio (11/165, 6.67% and 12/166, 7.23% respective the groups of strains with genomic mutations defining the resistance to isoniazid, rifampicin and fluoruquinolones. No confident difference was found in mutation patterns of genome of tuberculous mycobacteria isolated from HIV positive and HIV negative tuberculosis patients. 

Essential Role of the ESX-5 Secretion System in Outer Membrane Permeability of Pathogenic Mycobacteria.

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Louis S Ates

2015-05-01

Full Text Available Mycobacteria possess different type VII secretion (T7S systems to secrete proteins across their unusual cell envelope. One of these systems, ESX-5, is only present in slow-growing mycobacteria and responsible for the secretion of multiple substrates. However, the role of ESX-5 substrates in growth and/or virulence is largely unknown. In this study, we show that esx-5 is essential for growth of both Mycobacterium marinum and Mycobacterium bovis. Remarkably, this essentiality can be rescued by increasing the permeability of the outer membrane, either by altering its lipid composition or by the introduction of the heterologous porin MspA. Mutagenesis of the first nucleotide-binding domain of the membrane ATPase EccC5 prevented both ESX-5-dependent secretion and bacterial growth, but did not affect ESX-5 complex assembly. This suggests that the rescuing effect is not due to pores formed by the ESX-5 membrane complex, but caused by ESX-5 activity. Subsequent proteomic analysis to identify crucial ESX-5 substrates confirmed that all detectable PE and PPE proteins in the cell surface and cell envelope fractions were routed through ESX-5. Additionally, saturated transposon-directed insertion-site sequencing (TraDIS was applied to both wild-type M. marinum cells and cells expressing mspA to identify genes that are not essential anymore in the presence of MspA. This analysis confirmed the importance of esx-5, but we could not identify essential ESX-5 substrates, indicating that multiple of these substrates are together responsible for the essentiality. Finally, examination of phenotypes on defined carbon sources revealed that an esx-5 mutant is strongly impaired in the uptake and utilization of hydrophobic carbon sources. Based on these data, we propose a model in which the ESX-5 system is responsible for the transport of cell envelope proteins that are required for nutrient uptake. These proteins might in this way compensate for the lack of Msp

Essential Role of the ESX-5 Secretion System in Outer Membrane Permeability of Pathogenic Mycobacteria

KAUST Repository

Ates, Louis S.

2015-05-04

Mycobacteria possess different type VII secretion (T7S) systems to secrete proteins across their unusual cell envelope. One of these systems, ESX-5, is only present in slow-growing mycobacteria and responsible for the secretion of multiple substrates. However, the role of ESX-5 substrates in growth and/or virulence is largely unknown. In this study, we show that esx-5 is essential for growth of both Mycobacterium marinum and Mycobacterium bovis. Remarkably, this essentiality can be rescued by increasing the permeability of the outer membrane, either by altering its lipid composition or by the introduction of the heterologous porin MspA. Mutagenesis of the first nucleotide-binding domain of the membrane ATPase EccC5 prevented both ESX-5-dependent secretion and bacterial growth, but did not affect ESX-5 complex assembly. This suggests that the rescuing effect is not due to pores formed by the ESX-5 membrane complex, but caused by ESX-5 activity. Subsequent proteomic analysis to identify crucial ESX-5 substrates confirmed that all detectable PE and PPE proteins in the cell surface and cell envelope fractions were routed through ESX-5. Additionally, saturated transposon-directed insertion-site sequencing (TraDIS) was applied to both wild-type M. marinum cells and cells expressing mspA to identify genes that are not essential anymore in the presence of MspA. This analysis confirmed the importance of esx-5, but we could not identify essential ESX-5 substrates, indicating that multiple of these substrates are together responsible for the essentiality. Finally, examination of phenotypes on defined carbon sources revealed that an esx-5 mutant is strongly impaired in the uptake and utilization of hydrophobic carbon sources. Based on these data, we propose a model in which the ESX-5 system is responsible for the transport of cell envelope proteins that are required for nutrient uptake. These proteins might in this way compensate for the lack of MspA-like porins in slow

Essential Role of the ESX-5 Secretion System in Outer Membrane Permeability of Pathogenic Mycobacteria

KAUST Repository

Ates, Louis S.; Ummels, Roy; Commandeur, Susanna; van der Weerd, Robert; Sparrius, Marion; Weerdenburg, Eveline; Alber, Marina; Kalscheuer, Rainer; Piersma, Sander R.; Abdallah, Abdallah; Abd El Ghany, Moataz; Abdel-Haleem, Alyaa M.; Pain, Arnab; Jimé nez, Connie R.; Bitter, Wilbert; Houben, Edith N.G.

2015-01-01

Mycobacteria possess different type VII secretion (T7S) systems to secrete proteins across their unusual cell envelope. One of these systems, ESX-5, is only present in slow-growing mycobacteria and responsible for the secretion of multiple substrates. However, the role of ESX-5 substrates in growth and/or virulence is largely unknown. In this study, we show that esx-5 is essential for growth of both Mycobacterium marinum and Mycobacterium bovis. Remarkably, this essentiality can be rescued by increasing the permeability of the outer membrane, either by altering its lipid composition or by the introduction of the heterologous porin MspA. Mutagenesis of the first nucleotide-binding domain of the membrane ATPase EccC5 prevented both ESX-5-dependent secretion and bacterial growth, but did not affect ESX-5 complex assembly. This suggests that the rescuing effect is not due to pores formed by the ESX-5 membrane complex, but caused by ESX-5 activity. Subsequent proteomic analysis to identify crucial ESX-5 substrates confirmed that all detectable PE and PPE proteins in the cell surface and cell envelope fractions were routed through ESX-5. Additionally, saturated transposon-directed insertion-site sequencing (TraDIS) was applied to both wild-type M. marinum cells and cells expressing mspA to identify genes that are not essential anymore in the presence of MspA. This analysis confirmed the importance of esx-5, but we could not identify essential ESX-5 substrates, indicating that multiple of these substrates are together responsible for the essentiality. Finally, examination of phenotypes on defined carbon sources revealed that an esx-5 mutant is strongly impaired in the uptake and utilization of hydrophobic carbon sources. Based on these data, we propose a model in which the ESX-5 system is responsible for the transport of cell envelope proteins that are required for nutrient uptake. These proteins might in this way compensate for the lack of MspA-like porins in slow

Comparing the harmful effects of nontuberculous mycobacteria and Gram negative bacteria on lung function in patients with cystic fibrosis

DEFF Research Database (Denmark)

Qvist, Tavs; Taylor-Robinson, David; Waldmann, Elisabeth

2015-01-01

BACKGROUND: To better understand the relative effects of infection with nontuberculous mycobacteria and Gram negative bacteria on lung function decline in cystic fibrosis, we assessed the impact of each infection in a Danish setting. METHODS: Longitudinal registry study of 432 patients with cystic...

Mycobacteria in water used for personal hygiene in heavy industry and collieries: a potential risk for employees.

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Ulmann, Vit; Kracalikova, Anna; Dziedzinska, Radka

2015-03-04

Environmental mycobacteria (EM) constitute a health risk, particularly for immunocompromised people. Workers in heavy industry and in collieries represent an at-risk group of people as their immunity is often weakened by long-term employment in dusty environments, frequent smoking and an increased occurrence of pulmonary diseases. This study was concerned with the presence of EM in non-drinking water used for the hygiene of employees in six large industrial companies and collieries. Over a period of ten years, 1096 samples of surface water treated for hygiene purposes (treated surface water) and treated surface water diluted with mining water were examined. EM were detected in 63.4 and 41.5% samples of treated surface water and treated surface water diluted with mining water, respectively. Mycobacterium gordonae, M. avium-intracellulare and M. kansasii were the most frequently detected species. Adoption of suitable precautions should be enforced to reduce the incidence of mycobacteria in shower water and to decrease the infectious pressure on employees belonging to an at-risk group of people.

Mycobacteria in Water Used for Personal Hygiene in Heavy Industry and Collieries: A Potential Risk for Employees

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Vit Ulmann

2015-03-01

Full Text Available Environmental mycobacteria (EM constitute a health risk, particularly for immunocompromised people. Workers in heavy industry and in collieries represent an at-risk group of people as their immunity is often weakened by long-term employment in dusty environments, frequent smoking and an increased occurrence of pulmonary diseases. This study was concerned with the presence of EM in non-drinking water used for the hygiene of employees in six large industrial companies and collieries. Over a period of ten years, 1096 samples of surface water treated for hygiene purposes (treated surface water and treated surface water diluted with mining water were examined. EM were detected in 63.4 and 41.5% samples of treated surface water and treated surface water diluted with mining water, respectively. Mycobacterium gordonae, M. avium-intracellulare and M. kansasii were the most frequently detected species. Adoption of suitable precautions should be enforced to reduce the incidence of mycobacteria in shower water and to decrease the infectious pressure on employees belonging to an at-risk group of people.

ISOLATION AND ANTIBIOTIC SUSCEPTIBILITY TESTING OF RAPIDLY-GROWING MYCOBACTERIA FROM GRASSLAND SOILS

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Martina Kyselková

2013-08-01

Full Text Available Rapidly growing mycobacteria (RGM are common soil saprophytes, but certain strains cause infections in human and animals. The infections due to RGM have been increasing in past decades and are often difficult to treat. The susceptibility to antibiotics is regularly evaluated in clinical isolates of RGM, but the data on soil RGM are missing. The objectives of this study was to isolate RGM from four grassland soils with different impact of manuring, and assess their resistance to antibiotics and the ability to grow at 37°C and 42°C. Since isolation of RGM from soil is a challenge, a conventional decontamination method (NaOH/malachite green/cycloheximide and a recent method based on olive oil/SDS demulsification were compared. The olive oil/SDS method was less efficient, mainly because of the emulsion instability and plate overgrowing with other bacteria. Altogether, 44 isolates were obtained and 23 representatives of different RGM genotypes were screened. The number of isolates per soil decreased with increasing soil pH, consistently with previous findings that mycobacteria were more abundant in low pH soils. Most of the isolates belonged to the Mycobacterium fortuitum group. The majority of isolates was resistant to 2-4 antibiotics. Multiresistant strains occurred also in a control soil that has a long history without the exposure to antibiotic-containing manure. Seven isolates grew at 37°C, including the species M. septicum and M. fortuitum known for infections in humans. This study shows that multiresistant RGM close to known human pathogens occur in grassland soils regardless the soil history of manuring.

Duplex detection of the Mycobacterium tuberculosis complex and medically important non-tuberculosis mycobacteria by real-time PCR based on the rnpB gene.

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Abdeldaim, Guma; Svensson, Erik; Blomberg, Jonas; Herrmann, Björn

2016-11-01

A duplex real-time PCR based on the rnpB gene was developed for Mycobacterium spp. The assay was specific for the Mycobacterium tuberculosis complex (MTB) and also detected all 19 tested species of non-tuberculous mycobacteria (NTM). The assay was evaluated on 404 clinical samples: 290 respiratory samples and 114 from tissue and other non-respiratory body sites. M. tuberculosis was detected by culture in 40 samples and in 30 samples by the assay. The MTB assay showed a sensitivity similar to Roche Cobas Amplicor MTB-PCR (Roche Molecular Systems, Pleasanton, CA, USA). There were only nine samples with non-tuberculous mycobacteria detected by culture. Six of them were detected by the PCR assay. © 2016 APMIS. Published by John Wiley & Sons Ltd.

Prevalence of Nontuberculous Mycobacteria among Extrapulmonary Tuberculosis Cases in Tertiary Care Centers in Northern India

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A. K. Maurya

2015-01-01

Full Text Available The reports of nontuberculous mycobacteria (NTM associated with extrapulmonary diseases are increasing in tertiary care hospitals. Despite a significant increase in knowledge about NTM infections, they still represent a diagnostic and therapeutic challenge. The aim of this study is to know the prevalence of NTN among extrapulmonary tuberculosis cases in tertiary care centers in Northern India. A total of 227 culture positive isolates from 756 cases were tested for niacin production and catalase assay. BIO-LINE SD Ag MPT64 TB test and final identification and differentiation between MTBC and different species of NTM were further confirmed by GenoType Mycobacterium CM/AS assay. 71 cases (9.3% were positive for AFB by ZN staining and 227 cases (30.1% were positive for mycobacteria by culture. Niacin production and catalase activity were negative in 62/227 (27.4% strains and after using a panel of different biochemicals and final confirmation by GenoType Mycobacterium CM assay. Out of 227 cultures tested, 165 (72.6% strains were confirmed as M. tuberculosis complex, and 62 (27.4% were confirmed as NTM. The most common NTM species identified were M. fortuitum 17 (27.5% and M. intracellulare 13 (20.9%. The rapid identification of NTM species may help in targeted therapy and management of the diseases.

In vitro activity of flomoxef against rapidly growing mycobacteria.

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Tsai, Moan-Shane; Tang, Ya-Fen; Eng, Hock-Liew

2008-06-01

The aim of this study was to determine the in vitro sensitivity of rapidly growing mycobacteria (RGM) to flomoxef in respiratory secretions collected from 61 consecutive inpatients and outpatients at Chang Gung Memorial Hospital-Kaohsiung medical center between July and December, 2005. Minimal inhibitory concentrations (MIC) of flomoxef were determined by the broth dilution method for the 61 clinical isolates of RGMs. The MICs of flomoxef at which 90% of clinical isolates were inhibited was >128 microg/mL in 26 isolates of Mycobacterium abscessus and 4 microg/mL in 31 isolates of M. fortuitum. Three out of 4 clinical M. peregrinum isolates were inhibited by flomoxef at concentrations of 4 microg/mL or less. Although the numbers of the clinical isolates of RGMs were small, these preliminary in vitro results demonstrate the potential activity of flomoxef in the management of infections due to M. fortuitum, and probably M. peregrinum in humans.

Nontuberculous Mycobacteria Infections at a Provincial Reference Hospital, Cambodia.

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Bonnet, Maryline; San, Kim Chamroeun; Pho, Yati; Sok, Chandara; Dousset, Jean-Philippe; Brant, William; Hurtado, Northan; Eam, Khun Kim; Ardizzoni, Elisa; Heng, Seiha; Godreuil, Sylvain; Yew, Wing-Wai; Hewison, Cathy

2017-07-01

Prevalence of nontuberculous mycobacteria (NTM) disease is poorly documented in countries with high prevalence of tuberculosis (TB). We describe prevalence, risk factors, and TB program implications for NTM isolates and disease in Cambodia. A prospective cohort of 1,183 patients with presumptive TB underwent epidemiologic, clinical, radiologic, and microbiologic evaluation, including >12-months of follow-up for patients with NTM isolates. Prevalence of NTM isolates was 10.8% and of disease was 0.9%; 217 (18.3%) patients had TB. Of 197 smear-positive patients, 171 (86.8%) had TB confirmed (167 by culture and 4 by Xpert MTB/RIF assay only) and 11 (5.6%) had NTM isolates. HIV infection and past TB were independently associated with having NTM isolates. Improved detection of NTM isolates in Cambodia might require more systematic use of mycobacterial culture and the use of Xpert MTB/RIF to confirm smear-positive TB cases, especially in patients with HIV infection or a history of TB.

Acid-fast Smear and Histopathology Results Provide Guidance for the Appropriate Use of Broad-Range Polymerase Chain Reaction and Sequencing for Mycobacteria.

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Miller, Kennon; Harrington, Susan M; Procop, Gary W

2015-08-01

New molecular diagnostic tests are attractive because of the potential they hold for improving diagnostics in microbiology. The value of these tests, which is often assumed, should be investigated to determine the best use of these potentially powerful tools. To investigate the usefulness of broad-range polymerase chain reaction (PCR), followed by sequencing, in mycobacterial infections. We reviewed the test performance of acid-fast bacilli (AFB) PCR and traditional diagnostic methods (histopathology, AFB smear, and culture). We assessed the diagnostic effect and cost of the unrestricted ordering of broad-range PCR for the detection and identification of mycobacteria in clinical specimens. The AFB PCR was less sensitive than culture and histopathology and was less specific than culture, AFB smear, and histopathology. During 18 months, $93 063 was spent on 183 patient specimens for broad-range PCR and DNA sequencing for mycobacteria to confirm one culture-proven Mycobacterium tuberculosis infection that was also known to be positive by AFB smear and histopathology. In this cohort, there was a false-negative AFB PCR for M tuberculosis and a false-positive AFB PCR for Mycobacterium lentiflavum . Testing of AFB smear-negative specimens from patients without an inflammatory response supportive of a mycobacterial infection is costly and has not been proven to improve patient care. Traditional diagnostics (histopathology, AFB smear, and culture) should remain the primary methods for the detection of mycobacteria in clinical specimens.

Regulation of macrophage accessory cell activity by mycobacteria. I. Ia expression in normal and irradiated mice infected with Mycobacterium mycroti

International Nuclear Information System (INIS)

Kaye, P.M.; Feldmann, M.

1986-01-01

CBA/Ca mice were infected by either the intravenous or intraperitoneal route with Mycobacterium microti and the subsequent changes in local macrophage populations examined. Following infection, the number of macrophages increased and they showed greater expression of both MHC Class II molecules. This response was not dependent on viability of the mycobacteria, in contrast to reports with other microorganisms such as Listeria. Studies in sublethally irradiated mice indicated that persistent antigen could give rise to a response after a period of host recovery which was radiation dose dependent. This procedure also highlighted differences in the regulation of different murine class II antigens in vivo, as seen by delayed re-expression of I-E antigens. Macrophage accessory cell function, as assessed by an in vitro T cell proliferation assay, correlated with Ia expression after fixation, but not after indomethacin treatment; this highlights the diverse nature of regulatory molecules produced by these cells. (author)

Mycobacteria contain two groEL genes: the second Mycobacterium leprae groEL gene is arranged in an operon with groES

NARCIS (Netherlands)

Rinke de Wit, T. F.; Bekelie, S.; Osland, A.; Miko, T. L.; Hermans, P. W.; van Soolingen, D.; Drijfhout, J. W.; Schöningh, R.; Janson, A. A.; Thole, J. E.

1992-01-01

In contrast to other bacterial species, mycobacteria were thus far considered to contain groEL and groES genes that are present on separate loci on their chromosomes, Here, by screening a Mycobacterium leprae lambda gt11 expression library with serum from an Ethiopian lepromatous leprosy patient,

Identification of non-tuberculous mycobacteria isolated from clinical specimens at a tertiary care hospital: a cross-sectional study.

Science.gov (United States)

Ahmed, Imran; Jabeen, Kauser; Hasan, Rumina

2013-10-22

Non-tuberculous mycobacteria (NTM) are opportunistic pathogens in immuno-compromised patients. They are also increasingly recognized as pathogens in immuno-competent individuals. Globally, an increase in NTM isolation is being reported with a varied geographic prevalence of different species around the world. There is lack of data on species distribution of these organisms from Pakistan. Treatment options differ according to the species isolated and its susceptibility profile. Knowledge of local species variation would help targeted therapy. This study was performed to determine frequencies of different NTM species isolated from various clinical specimens submitted at a tertiary care hospital laboratory. NTM isolated from 25955 clinical specimens over a period of two years (2010 to 2011) were included. All NTM were identified using conventional tests. Drug susceptibility testing (DST) was performed by broth microdilution and interpreted according to Clinical and Laboratory Standards Institute's document M24-A2. A total of 104 NTM were included in the study. Of these, 76% (54/71) rapidly growing mycobacteria (RGM) and 57.6% (19/33) slow growing mycobacteria (SGM) could be further identified. Mycobacterium fortuitum (21/54) was the commonest NTM identified among RGM followed by M. mucogenicum (12/54) and M. smegmatis (11/54). Among SGM, M. avium complex (MAC) was the most frequent (14/19). Clinical significance could be assessed in a limited number (52/104) of NTM isolates and MAC appeared to be the commonest significant NTM. Three extra-pulmonary cases were found to be healthcare associated infections. DST results for RGM showed susceptibility to amikacin (100%), clarithromycin (100%, except M. fortuitum where it is not reportable), linezolid (90%) and moxifloxacin (75%). Whereas SGM were susceptible to clarithromycin (100%), linezolid (58.8%) and moxifloxacin (64.7%). This is the first study reporting NTM species and their clinical significance isolated from

Comparison among three methods for mycobacteria identification Comparación entre tres métodos para identificar micobacterias

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Misael Mondragón-Barreto

2000-11-01

Full Text Available OBJECTIVE: To compare three methods: Biochemical tests, high-performance liquid chromatography (HPLC and polymerase chain reaction-restriction fragments length polymorphism (PCR-RFLP, for the identification of mycobacteria, and to perform a cost-benefit analysis to define an optimum identification algorithm. MATERIAL AND METHODS: One-hundred-and-seven mycobacteria isolates were identified by the three methods at Instituto de Diagnóstico y Referencia Epidemiológicos, between February of 1999 and January of 2000 and the results were compared with those of a reference laboratory using the Q-Cochran statistical test. RESULTS: PCR-RFLP was the most rapid and specific procedure but also the most expensive; biochemical tests excelled for identification of Mycobacterium tuberculosis, but were lengthy and expensive for other mycobacteria; HPLC ranked in the middle for price, speed and specificity. CONCLUSIONS: Considering the expected proportion of M. tuberculosis, the following algorithm was proposed: Initially, biochemical tests should be performed; if the results indicate a non-tuberculous mycobacteria, the isolate should be analyzed with HPLC; if results are unclear, the isolate should be analyzed using PCR-RFLP. Isolates showing a previously undescribed PCR-RFLP pattern should be characterized by DNA sequencing.OBJETIVO: Comparar tres métodos: pruebas bioquímicas, cromatografía líquida de alta resolución (HPLC, por sus siglas en inglés y reacción en cadena de la polimerasa-polimorfismo del tamaño de fragmentos de restricción (PCR-RFLP para identificar micobacterias a nivel especie, analizando costo-beneficio y proponiendo un algoritmo de identificación. MATERIAL Y MÉTODOS: Entre febrero de 1999 y enero de 2000, en los laboratorios del Instituto de Diagnóstico y Referencia Epidemiológicos se tipificaron 107 aislados de micobacterias y los resultados se compararon con los obtenidos en un laboratorio de referencia utilizando la prueba

Nontuberculous mycobacteria in non-AIDS patients

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A. Marinho

2008-05-01

Full Text Available Nontuberculous mycobacteria (NTM play an increasingly significant pathogenic role in HIV-positive patients, in patients with chronic lung disease, in other chronic conditions and in the elderly. Aims: Evaluate the importance of NTM isolation in respiratory samples in patients without HIV-infection. Methods: Retrospective evaluation of our hospital patients with no known AIDS, with at least one NTM positive respiratory sample, from 1997-2004. Results: We found 102 patients, with a median age of 63 years; 67% male. Sixty-three (62% had underlying lung disease, mainly tuberculosis sequelae (n = 19. The majority (47% of the isolations were Mycobacterium avium complex (MAC.A diagnosis of Mycobacterium pulmonary disease was made in 16 patients (15.7%, 14 of which met the American Thoracic Society diagnostic criteria. Ten male and 6 female; median age 65 years. Twelve had underlying lung disease. All of them had respiratory infection complaints. Chest X-rays showed mainly pulmonary infiltrates, linear opacities and cavitation. MAC was the cause of mycobacterium respiratory disease in 12 patients (75%. Conclusion: NTM isolation did not equal pulmonary NTM disease in the majority of cases, even in patients with underlying lung disease. MAC was the most commonly isolated agent and its relative importance was higher in the presence of NTM disease. Resumo: As micobactérias não tuberculosas (MNT têm um papel patogénico de importância crescente em doentes com serologia positiva para o vírus da imunodeficiência humana (VIH, em doentes com doença pulmonar crónica, em outras doencas crónicas, e ainda nos idosos. Objectivo: Avaliar a importância do isolamento de MNT em amostras respiratórias em doentes adultos sem infecção VIH. Material e métodos: Estudo retrospectivo dos doentes do Hospital de São João sem infecção VIH conhecida, com pelo menos uma amostra respiratória positiva para MNT, entre 1997 e 2004. Resultados: Foram encontrados 102

Nontuberculous mycobacteria infection after mesotherapy: preliminary report of 15 cases.

Science.gov (United States)

Sañudo, Alejandra; Vallejo, Fernando; Sierra, Martha; Hoyos, Juan G; Yepes, Sandra; Wolff, Juan Carlos; Correa, Luis A; Montealegre, Carlos; Navarro, Pilar; Bedoya, Elina; Sanclemente, Gloria

2007-06-01

Mesotherapy is an increasingly used technique which is currently causing several mycobacterial infections owing to contaminated substances being injected, and also to poor aseptic measures being held by nonprofessional practitioners. We collected 15 cases of nontuberculous mycobacteria (NTM) infection after mesotherapy in a 6-month period. All patients were female with ages ranging from 19 to 52 years; the main substances injected were procaine and lecithin, and the time between mesotherapy and the appearance of the lesions varied between 1 and 12 weeks. Clinical lesions were mostly nodules and abscesses, which were localized in the abdomen and buttocks in the majority of cases. The main patient complaint was local pain but some presented with systemic symptoms such as fever and malaise. Biopsies reported granulomatous chronic inflammation in the majority of cases. Skin cultures were positive for NTM and Mycobacterium chelonae. Mesotherapy not performed with quality controlled substances can be a predisposing factor for NTM infection.

Natural disasters and nontuberculous mycobacteria: a recipe for increased disease?

Science.gov (United States)

Honda, Jennifer R; Bernhard, Jon N; Chan, Edward D

2015-02-01

Infectious diseases acquired by survivors of large-scale natural disasters complicate the recovery process. During events such as tsunamis, hurricanes, earthquakes, and tornados and well into the recovery period, victims often are exposed to water-soil mixtures that have relocated with indigenous microbes. Because nontuberculous mycobacteria (NTM) are ubiquitous in water and soil, there is potential for increased exposure to these organisms during natural disasters. In this hypothesis-driven commentary, we discuss the rise in NTM lung disease and natural disasters and examine the geographic overlap of NTM infections and disaster frequencies in the United States. Moreover, we show an increased number of positive NTM cultures from Louisiana residents in the years following three of the relatively recent epic hurricanes and posit that such natural disasters may help to drive the increased number of NTM infections. Finally, we advocate for increased environmental studies and surveillance of NTM infections before and after natural disasters.

Baby bottle steam sterilizers for disinfecting home nebulizers inoculated with non-tuberculous mycobacteria.

Science.gov (United States)

Towle, D; Callan, D A; Lamprea, C; Murray, T S

2016-03-01

Non-tuberculous mycobacteria (NTMb), present in environmental water sources, can contribute to respiratory infection in patients with chronic pulmonary disease. Contaminated nebulizers are a potential source of respiratory infection. Treatment with baby bottle steam sterilizers disinfects home nebulizers inoculated with bacterial pathogens but whether this method works for disinfection of NTMb is unclear. Baby bottle steam sterilization was compared with vigorous water washing for disinfecting home nebulizers inoculated with NTMb mixed with cystic fibrosis sputum. No NTMb was recovered from any nebulizers after steam treatment whereas viable NTMb grew after water washing, demonstrating that steam sterilization effectively disinfects NTMb-inoculated nebulizers. Copyright © 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Are we overlooking infections owing to non-tuberculous mycobacteria during routine conventional laboratory investigations?

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Kushal Garima

2012-01-01

Full Text Available A large number of potentially pathogenic non-tuberculous mycobacteria (NTM encountered in the clinical laboratory makes it necessary to identify their species to ensure appropriate treatment. However, labor-intensive conventional methods of speciation are not used in every laboratory, and hence NTM infections are often ignored. Polymerase chain reaction (PCR restriction analysis (PRA was applied in this study for early identification and speciation of mycobacterial species on 306 cultures of acid-fast bacilli isolated from patients suspected of suffering from tuberculosis. Mycobacterium tuberculosis was identified in 85.6% of the isolates. The NTM isolated most commonly was Mycobacterium kansasii/gastri group (3.5%, followed by Mycobacterium fortuitum (3.2%. Four of the M. fortuitum were grown from cultures obtained on the same day, but from samples from different patients and were probably laboratory contaminants. Mycobacterium intracellulare and Mycobacterium avium were identified in 2.94% and 2.28% of the isolates, respectively. Three isolates of M. avium and two isolates of M. intracellulare were obtained in repeated cultures from sputum samples of the same patients and were thus pathogenic. A single isolate of Mycobacterium abscessus was obtained from a breast abscess. A rare pathogen Mycobacterium phocaicum was isolated from one patient with epididymitis. However, whether it was the causative agent of epididymitis in this patient remains doubtful. The results of this study highlight the importance of speciation of mycobacteria for appropriate diagnosis and the importance of including molecular assays to augment conventional methods of diagnosis of mycobacterial diseases for rapid identification of NTM so that these potential pathogens are not overlooked in routine diagnostic procedures.

Interactive Effects of Corrosion, Copper, and Chloramines on Legionella and Mycobacteria in Hot Water Plumbing.

Science.gov (United States)

Rhoads, William J; Pruden, Amy; Edwards, Marc A

2017-06-20

Complexities associated with drinking water plumbing systems can result in undesirable interactions among plumbing components that undermine engineering controls for opportunistic pathogens (OPs). In this study, we examine the effects of plumbing system materials and two commonly applied disinfectants, copper and chloramines, on water chemistry and the growth of Legionella and mycobacteria across a transect of bench- and pilot-scale hot water experiments carried out with the same municipal water supply. We discovered that copper released from corrosion of plumbing materials can initiate evolution of >1100 times more hydrogen (H 2 ) from water heater sacrificial anode rods than does presence of copper dosed as soluble cupric ions. H 2 is a favorable electron donor for autotrophs and causes fixation of organic carbon that could serve as a nutrient for OPs. Dosed cupric ions acted as a disinfectant in stratified stagnant pipes, inhibiting culturable Legionella and biofilm formation, but promoted Legionella growth in pipes subject to convective mixing. This difference was presumably due to continuous delivery of nutrients to biofilm on the pipes under convective mixing conditions. Chloramines eliminated culturable Legionella and prevented L. pneumophila from recolonizing biofilms, but M. avium gene numbers increased by 0.14-0.76 logs in the bulk water and were unaffected in the biofilm. This study provides practical confirmation of past discrepancies in the literature regarding the variable effects of copper on Legionella growth, and confirms prior reports of trade-offs between Legionella and mycobacteria if chloramines are applied as secondary disinfectant residual.

Antibiotic management of lung infections in cystic fibrosis. II. Nontuberculous mycobacteria, anaerobic bacteria, and fungi.

Science.gov (United States)

Chmiel, James F; Aksamit, Timothy R; Chotirmall, Sanjay H; Dasenbrook, Elliott C; Elborn, J Stuart; LiPuma, John J; Ranganathan, Sarath C; Waters, Valerie J; Ratjen, Felix A

2014-10-01

Airway infections are a key component of cystic fibrosis (CF) lung disease. Whereas the approach to common pathogens such as Pseudomonas aeruginosa is guided by a significant body of evidence, other infections often pose a considerable challenge to treating physicians. In Part I of this series on the antibiotic management of difficult lung infections, we discussed bacterial organisms including methicillin-resistant Staphylococcus aureus, gram-negative bacterial infections, and treatment of multiple bacterial pathogens. Here, we summarize the approach to infections with nontuberculous mycobacteria, anaerobic bacteria, and fungi. Nontuberculous mycobacteria can significantly impact the course of lung disease in patients with CF, but differentiation between colonization and infection is difficult clinically as coinfection with other micro-organisms is common. Treatment consists of different classes of antibiotics, varies in intensity, and is best guided by a team of specialized clinicians and microbiologists. The ability of anaerobic bacteria to contribute to CF lung disease is less clear, even though clinical relevance has been reported in individual patients. Anaerobes detected in CF sputum are often resistant to multiple drugs, and treatment has not yet been shown to positively affect patient outcome. Fungi have gained significant interest as potential CF pathogens. Although the role of Candida is largely unclear, there is mounting evidence that Scedosporium species and Aspergillus fumigatus, beyond the classical presentation of allergic bronchopulmonary aspergillosis, can be relevant in patients with CF and treatment should be considered. At present, however there remains limited information on how best to select patients who could benefit from antifungal therapy.

Pretreatment of clinical specimens with sodium dodecyl (lauryl) sulfate is not suitable for the mycobacteria growth indicator tube cultivation method.

OpenAIRE

Pfyffer, G E; Welscher, H M; Kissling, P

1997-01-01

When using the Mycobacteria Growth Indicator Tube (MGIT), pretreatment of clinical specimens with N-acetyl-L-cysteine-NaOH is recommended by the manufacturer. Processing of clinical specimens (n = 1,000) with sodium dodecyl (lauryl) sulfate-NaOH resulted in both poor recovery and delayed mean time to detection of acid-fast bacilli. Values were comparable to those obtained on solid media.

Source tracking Mycobacterium ulcerans infections in the Ashanti region, Ghana.

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Charles A Narh

2015-01-01

Full Text Available Although several studies have associated Mycobacterium ulcerans (MU infection, Buruli ulcer (BU, with slow moving water bodies, there is still no definite mode of transmission. Ecological and transmission studies suggest Variable Number Tandem Repeat (VNTR typing as a useful tool to differentiate MU strains from other Mycolactone Producing Mycobacteria (MPM. Deciphering the genetic relatedness of clinical and environmental isolates is seminal to determining reservoirs, vectors and transmission routes. In this study, we attempted to source-track MU infections to specific water bodies by matching VNTR profiles of MU in human samples to those in the environment. Environmental samples were collected from 10 water bodies in four BU endemic communities in the Ashanti region, Ghana. Four VNTR loci in MU Agy99 genome, were used to genotype environmental MU ecovars, and those from 14 confirmed BU patients within the same study area. Length polymorphism was confirmed with sequencing. MU was present in the 3 different types of water bodies, but significantly higher in biofilm samples. Four MU genotypes, designated W, X, Y and Z, were typed in both human and environmental samples. Other reported genotypes were only found in water bodies. Animal trapping identified 1 mouse with lesion characteristic of BU, which was confirmed as MU infection. Our findings suggest that patients may have been infected from community associated water bodies. Further, we present evidence that small mammals within endemic communities could be susceptible to MU infections. M. ulcerans transmission could involve several routes where humans have contact with risk environments, which may be further compounded by water bodies acting as vehicles for disseminating strains.

Rapidly growing mycobacteria in Singapore, 2006-2011.

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Tang, S S; Lye, D C; Jureen, R; Sng, L-H; Hsu, L Y

2015-03-01

Nontuberculous mycobacteria infection is a growing global concern, but data from Asia are limited. This study aimed to describe the distribution and antibiotic susceptibility profiles of rapidly growing mycobacterium (RGM) isolates in Singapore. Clinical RGM isolates with antibiotic susceptibility tests performed between 2006 and 2011 were identified using microbiology laboratory databases and minimum inhibitory concentrations of amikacin, cefoxitin, clarithromycin, ciprofloxacin, doxycycline, imipenem, linezolid, moxifloxacin, sulfamethoxazole or trimethoprim-sulfamethoxazole, tigecycline and tobramycin were recorded. Regression analysis was performed to detect changes in antibiotic susceptibility patterns over time. A total of 427 isolates were included. Of these, 277 (65%) were from respiratory specimens, 42 (10%) were related to skin and soft tissue infections and 36 (8%) were recovered from blood specimens. The two most common species identified were Mycobacterium abscessus (73%) and Mycobacterium fortuitum group (22%), with amikacin and clarithromycin being most active against the former, and quinolones and trimethoprim-sulfamethoxazole against the latter. Decreases in susceptibility of M. abscessus to linezolid by 8.8% per year (p 0.001), M. fortuitum group to imipenem by 9.5% per year (p 0.023) and clarithromycin by 4.7% per year (p 0.033) were observed. M. abscessus in respiratory specimens is the most common RGM identified in Singapore. Antibiotic options for treatment of RGM infections are increasingly limited. Copyright © 2014 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Increase in nontuberculous mycobacteria isolated in Shanghai, China: results from a population-based study.

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Jie Wu

Full Text Available BACKGROUND: In China, the prevalence of nontuberculous mycobacteria (NTM in isolates from mycobacterial culture-positive patients with pulmonary tuberculosis (TB is largely unknown. METHODS: We used conventional biochemical and 16S rRNA gene sequencing to identify species of mycobacteria in specimens from patients suspected of having TB. Drug-susceptibility testing was performed on NTM isolates using the proportion method. We also determined the independent risk factors associated with infection with NTM compared with infection with Mycobacterium tuberculosis. RESULTS: The overall rate of NTM isolated from mycobacterial culture-positive patients was 5.9% in this population, with a significantly increasing trend from 3.0% in 2008 to 8.5% in 2012 (P for trend <0.001. The organism most frequently identified was M. kansasii (45.0%, followed by M. intracellulare (20.8% and M. chelonae/abscessus (14.9%. The overall proportion of isolates resistant to the four first-line anti-TB agents were 64.6% for isoniazid, 77.6% for streptomycin, 63.3% for rifampicin and 75.1% for ethambutol. The risk factors most often associated with NTM infection were older age (P for trend <0.001, being a resident of Shanghai (adjusted odds ratio [aOR], 1.48; 95% CI, 1.10-2.00, having been treated for tuberculosis (aOR, 1.64; 95% CI, 1.18-2.29, having a cavity on chest X-ray (aOR, 1.51; 95% CI, 1.16-1.96, and being sputum smear-negative (aOR, 1.59; 95% CI, 1.16-2.18. CONCLUSIONS: The prevalence of NTM isolated in Shanghai increased between 2008 and 2012, thus clinicians should consider NTM as a possible cause of TB-like disease. Accurate species identification is imperative so that proper treatment can be administered for diseases caused by the diversity of NTM species.

Single systemic administration of Ag85B of mycobacteria DNA inhibits allergic airway inflammation in a mouse model of asthma

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Karamatsu K

2012-12-01

Full Text Available Katsuo Karamatsu,1,2 Kazuhiro Matsuo,3 Hiroyasu Inada,4 Yusuke Tsujimura,1 Yumiko Shiogama,1,2 Akihiro Matsubara,1,2 Mitsuo Kawano,5 Yasuhiro Yasutomi1,21Laboratory of Immunoregulation and Vaccine Research, Tsukuba Primate Research Center, National Institute of Biomedical Innovation, Tsukuba, 2Division of Immunoregulation, Department of Molecular and Experimental Medicine, Mie University Graduate School of Medicine, Tsu, 3Department of Research and Development, Japan BCG Laboratory, Tokyo, 4Department of Pathology, Suzuka University of Medical Science, Suzuka, 5Department of Microbiology and Molecular Genetics, Mie University Graduate School of Medicine, Tsu, JapanAbstract: The immune responses of T-helper (Th and T-regulatory cells are thought to play a crucial role in the pathogenesis of allergic airway inflammation observed in asthma. The correction of immune response by these cells should be considered in the prevention and treatment of asthma. Native antigen 85B (Ag85B of mycobacteria, which cross-reacts among mycobacteria species, may play an important biological role in host–pathogen interaction since it elicits various immune responses by activation of Th cells. The current study investigated the antiallergic inflammatory effects of DNA administration of Ag85B from Mycobacterium kansasii in a mouse model of asthma. Immunization of BALB/c mice with alum-adsorbed ovalbumin followed by aspiration with aerosolized ovalbumin resulted in the development of allergic airway inflammation. Administration of Ag85B DNA before the aerosolized ovalbumin challenge protected the mice from subsequent induction of allergic airway inflammation. Serum and bronchoalveolar lavage immunoglobulin E levels, extent of eosinophil infiltration, and levels of Th2-type cytokines in Ag85B DNA-administered mice were significantly lower than those in control plasmid-immunized mice, and levels of Th1- and T-regulatory-type cytokines were enhanced by Ag85B

Amoebae as potential environmental hosts for Mycobacterium ulcerans and other mycobacteria, but doubtful actors in Buruli ulcer epidemiology.

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Sophie Gryseels

Full Text Available The reservoir and mode of transmission of Mycobacterium ulcerans, the causative agent of Buruli ulcer, remain unknown. Ecological, genetic and epidemiological information nonetheless suggests that M. ulcerans may reside in aquatic protozoa.We experimentally infected Acanthamoeba polyphaga with M. ulcerans and found that the bacilli were phagocytised, not digested and remained viable for the duration of the experiment. Furthermore, we collected 13 water, 90 biofilm and 45 detritus samples in both Buruli ulcer endemic and non-endemic communities in Ghana, from which we cultivated amoeboid protozoa and mycobacteria. M. ulcerans was not isolated, but other mycobacteria were as frequently isolated from intracellular as from extracellular sources, suggesting that they commonly infect amoebae in nature. We screened the samples as well as the amoeba cultures for the M. ulcerans markers IS2404, IS2606 and KR-B. IS2404 was detected in 2% of the environmental samples and in 4% of the amoeba cultures. The IS2404 positive amoeba cultures included up to 5 different protozoan species, and originated both from Buruli ulcer endemic and non-endemic communities.This is the first report of experimental infection of amoebae with M. ulcerans and of the detection of the marker IS2404 in amoeba cultures isolated from the environment. We conclude that amoeba are potential natural hosts for M. ulcerans, yet remain sceptical about their implication in the transmission of M. ulcerans to humans and their importance in the epidemiology of Buruli ulcer.

Nontuberculous mycobacteria: incidence in Southwest Ireland from 1987 to 2000.

LENUS (Irish Health Repository)

Kennedy, M P

2012-02-03

SETTING: The Southwest of Ireland (Counties Cork and Kerry) 1987-2000, average population 549,500. OBJECTIVE: Nontuberculous mycobacteria (NTM) cause significant morbidity worldwide and the study of epidemiology and characteristics helps in their prevention and treatment. This study was performed to determine the incidence of NTM disease in comparison to Mycobacterium tuberculosis (M. tuberculosis) and Mycobacterium bovis (M. bovis) in Southwest Ireland, over the above time period. DESIGN: A retrospective study was carried out in all human isolates of NTM, M. tuberculosis and M. bovis between 1987 and 2000, in the Southwest Region of Ireland. RESULTS: The mean incidence of NTM (0.4\\/100,000 population) has risen since 1995, principally of pulmonary Mycobacterium avium intracellulare complex (MAC). The annual incidence of M. tuberculosis in humans over 14 years in the same region was 971\\/100,000 population with a significant reduction since 1994 and M. bovis remained constant at 0.5\\/100,000 population. CONCLUSION: The increasing incidence of disease causing NTM noted in Southwest Ireland reflects global data and is surmised to be due to an ageing population, increased incidence related to chronic fibrotic lung disease, and environmental mycobacterial factors.

Increasing Recovery of Nontuberculous Mycobacteria from Respiratory Specimens over a 10-Year Period in a Tertiary Referral Hospital in South Korea.

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Koh, Won-Jung; Chang, Boksoon; Jeong, Byeong-Ho; Jeon, Kyeongman; Kim, Su-Young; Lee, Nam Yong; Ki, Chang-Seok; Kwon, O Jung

2013-11-01

The number of patients with pulmonary disease caused by nontuberculous mycobacteria (NTM) has been increasing worldwide. The aim of this study was to evaluate long-term trends in the NTM recovery rate from respiratory specimens over a 10-year period in a tertiary referral hospital in South Korea. We retrospectively reviewed the records of mycobacterial cultures of respiratory specimens at Samsung Medical Center from January 2001 to December 2011. During the study period, 32,841 respiratory specimens from 10,563 patients were found to be culture-positive for mycobacteria. These included 12,619 (38%) Mycobacterium tuberculosis and 20,222 (62%) NTM isolates. The proportion of NTM among all positive mycobacterial cultures increased from 43% (548/1,283) in 2001 to 70% (3,341/4,800) in 2011 (ptrend). The recovery rate of NTM isolates from acid-fast bacilli smear-positive specimens increased from 9% (38/417) in 2001 to 64% (1,284/1,997) in 2011 (ptrend). The proportion of positive liquid cultures was higher for NTM than for M. tuberculosis (p<0.001). The most frequently isolated NTM were Mycobacterium avium-intracellulare complex (53%) and Mycobacterium abscessus-massiliense complex (25%). The recovery rate of NTM from respiratory specimens in South Korea has increased steadily.

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

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JoĂŤl Pestel

2008-06-01

Full Text Available Mycobacterium bovis bacillus Calmette-GuĂŠrin (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.

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

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Kowalewicz-Kulbat, Magdalena; Kaźmierczak, Dominik; Donevski, Stefan; Biet, Franck; Pestel, Joël; Rudnicka, Wiesława

2008-01-01

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.

Sulfate Reducing Bacteria and Mycobacteria Dominate the Biofilm Communities in a Chloraminated Drinking Water Distribution System.

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Gomez-Smith, C Kimloi; LaPara, Timothy M; Hozalski, Raymond M

2015-07-21

The quantity and composition of bacterial biofilms growing on 10 water mains from a full-scale chloraminated water distribution system were analyzed using real-time PCR targeting the 16S rRNA gene and next-generation, high-throughput Illumina sequencing. Water mains with corrosion tubercles supported the greatest amount of bacterial biomass (n = 25; geometric mean = 2.5 × 10(7) copies cm(-2)), which was significantly higher (P = 0.04) than cement-lined cast-iron mains (n = 6; geometric mean = 2.0 × 10(6) copies cm(-2)). Despite spatial variation of community composition and bacterial abundance in water main biofilms, the communities on the interior main surfaces were surprisingly similar, containing a core group of operational taxonomic units (OTUs) assigned to only 17 different genera. Bacteria from the genus Mycobacterium dominated all communities at the main wall-bulk water interface (25-78% of the community), regardless of main age, estimated water age, main material, and the presence of corrosion products. Further sequencing of the mycobacterial heat shock protein gene (hsp65) provided species-level taxonomic resolution of mycobacteria. The two dominant Mycobacteria present, M. frederiksbergense (arithmetic mean = 85.7% of hsp65 sequences) and M. aurum (arithmetic mean = 6.5% of hsp65 sequences), are generally considered to be nonpathogenic. Two opportunistic pathogens, however, were detected at low numbers: M. hemophilum (arithmetic mean = 1.5% of hsp65 sequences) and M. abscessus (arithmetic mean = 0.006% of hsp65 sequences). Sulfate-reducing bacteria from the genus Desulfovibrio, which have been implicated in microbially influenced corrosion, dominated all communities located underneath corrosion tubercules (arithmetic mean = 67.5% of the community). This research provides novel insights into the quantity and composition of biofilms in full-scale drinking water distribution systems, which is critical for assessing the risks to public health and to the

Increasing Recovery of Nontuberculous Mycobacteria from Respiratory Specimens over a 10-Year Period in a Tertiary Referral Hospital in South Korea

OpenAIRE

Koh, Won-Jung; Chang, Boksoon; Jeong, Byeong-Ho; Jeon, Kyeongman; Kim, Su-Young; Lee, Nam Yong; Ki, Chang-Seok; Kwon, O Jung

2013-01-01

Background The number of patients with pulmonary disease caused by nontuberculous mycobacteria (NTM) has been increasing worldwide. The aim of this study was to evaluate long-term trends in the NTM recovery rate from respiratory specimens over a 10-year period in a tertiary referral hospital in South Korea. Methods We retrospectively reviewed the records of mycobacterial cultures of respiratory specimens at Samsung Medical Center from January 2001 to December 2011. Results During the study pe...

Occurrence of Mycobacterium bovis and non-tuberculous mycobacteria (NTM in raw and pasteurized milk in the northwestern region of Paraná, Brazil

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Sônia Aparecida Sgarioni

2014-06-01

Full Text Available Milk is widely consumed in Brazil and can be the vehicle of agent transmission. In this study, was evaluated the occurrence of Mycobacterium bovis and non-tuberculous mycobacteria (NTM in raw and pasteurized milk consumed in the northwestern region of Paraná, Brazil. Fifty-two milk samples (20 pasteurized and 32 raw from dairy farms near the municipality of Maringa, Parana State, Brazil were collected. Milk samples were decontaminated using 5% oxalic acid method and cultured on Lowenstein-Jensen and Stonebrink media at 35 °C and 30 °C, with and without 5-10% CO2. Mycobacteria isolates were identified by morphological features, PCR-Restriction Fragment Length Polymorphism Analysis (PCR-PRA and Mycolic acids analysis. Thirteen (25% raw and 2 (4% pasteurized milk samples were positive for acid fast bacilli growth. Nine different species of NTM were isolated (M. nonchromogenicum, M. peregrinum, M. smegmatis, M. neoaurum, M. fortuitum, M. chelonae, M. flavescens, M. kansasii and M. scrofulaceum. M. bovis was not detected. Raw and pasteurized milk may be considered one source for NTM human infection. The paper reinforces the need for intensification of measures in order to avoid the milk contamination and consequently prevent diseases in the south of Brazil.

Occurrence of Mycobacterium bovis and non-tuberculous mycobacteria (NTM) in raw and pasteurized milk in the northwestern region of Paraná, Brazil.

Science.gov (United States)

Sgarioni, Sônia Aparecida; Hirata, Rosario Dominguez Crespo; Hirata, Mario Hiroyuki; Leite, Clarice Queico Fujimura; de Prince, Karina Andrade; de Andrade Leite, Sergio Roberto; Filho, Dirceu Vedovello; Siqueira, Vera Lucia Dias; Caleffi-Ferracioli, Katiany Rizzieri; Cardoso, Rosilene Fressatti

2014-01-01

Milk is widely consumed in Brazil and can be the vehicle of agent transmission. In this study, was evaluated the occurrence of Mycobacterium bovis and non-tuberculous mycobacteria (NTM) in raw and pasteurized milk consumed in the northwestern region of Paraná, Brazil. Fifty-two milk samples (20 pasteurized and 32 raw) from dairy farms near the municipality of Maringa, Parana State, Brazil were collected. Milk samples were decontaminated using 5% oxalic acid method and cultured on Lowenstein-Jensen and Stonebrink media at 35 °C and 30 °C, with and without 5-10% CO2. Mycobacteria isolates were identified by morphological features, PCR-Restriction Fragment Length Polymorphism Analysis (PCR-PRA) and Mycolic acids analysis. Thirteen (25%) raw and 2 (4%) pasteurized milk samples were positive for acid fast bacilli growth. Nine different species of NTM were isolated (M. nonchromogenicum, M. peregrinum, M. smegmatis, M. neoaurum, M. fortuitum, M. chelonae, M. flavescens, M. kansasii and M. scrofulaceum). M. bovis was not detected. Raw and pasteurized milk may be considered one source for NTM human infection. The paper reinforces the need for intensification of measures in order to avoid the milk contamination and consequently prevent diseases in the south of Brazil.

Diversity, Community Composition, and Dynamics of Nonpigmented and Late-Pigmenting Rapidly Growing Mycobacteria in an Urban Tap Water Production and Distribution System

OpenAIRE

Dubrou, S.; Konjek, J.; Macheras, E.; Welté, B.; Guidicelli, L.; Chignon, E.; Joyeux, M.; Gaillard, J. L.; Heym, B.; Tully, T.; Sapriel, G.

2013-01-01

Nonpigmented and late-pigmenting rapidly growing mycobacteria (RGM) have been reported to commonly colonize water production and distribution systems. However, there is little information about the nature and distribution of RGM species within the different parts of such complex networks or about their clustering into specific RGM species communities. We conducted a large-scale survey between 2007 and 2009 in the Parisian urban tap water production and distribution system. We analyzed 1,418 w...

Iron Deprivation Affects Drug Susceptibilities of Mycobacteria Targeting Membrane Integrity

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Rahul Pal

2015-01-01

Full Text Available Multidrug resistance (MDR acquired by Mycobacterium tuberculosis (MTB through continuous deployment of antitubercular drugs warrants immediate search for novel targets and mechanisms. The ability of MTB to sense and become accustomed to changes in the host is essential for survival and confers the basis of infection. A crucial condition that MTB must surmount is iron limitation, during the establishment of infection, since iron is required by both bacteria and humans. This study focuses on how iron deprivation affects drug susceptibilities of known anti-TB drugs in Mycobacterium smegmatis, a “surrogate of MTB.” We showed that iron deprivation leads to enhanced potency of most commonly used first line anti-TB drugs that could be reverted upon iron supplementation. We explored that membrane homeostasis is disrupted upon iron deprivation as revealed by enhanced membrane permeability and hypersensitivity to membrane perturbing agent leading to increased passive diffusion of drug and TEM images showing detectable differences in cell envelope thickness. Furthermore, iron seems to be indispensable to sustain genotoxic stress suggesting its possible role in DNA repair machinery. Taken together, we for the first time established a link between cellular iron and drug susceptibility of mycobacteria suggesting iron as novel determinant to combat MDR.

Decolorization of Malachite Green and Crystal Violet by Waterborne Pathogenic Mycobacteria

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Jones, Jefferson J.; Falkinham III, Joseph O.

2003-01-01

Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium scrofulaceum, Mycobacterium marinum, and Mycobacterium chelonae tolerate high concentrations of the dyes malachite green and crystal violet. Cells of strains of those species decolorized (reduced) both malachite green and crystal violet. Because decolorized malachite green lacked antimicrobial activity, the resistance of these mycobacteria could be due, in part, to their ability to decolorize the dyes. Small amounts of malachite green and its reduced, decolorized product were detected in the lipid fraction of M. avium strain A5 cells grown in the presence of malachite green, suggesting that a minor component of resistance could be due to sequestering the dyes in the extensive mycobacterial cell surface lipid. The membrane fraction of M. avium strain A5 had at least a fivefold-higher specific decolorization rate than did the crude extract, suggesting that the decolorization activity is membrane associated. The malachite green-decolorizing activity of the membrane fraction of M. avium strain A5 was abolished by either boiling or proteinase exposure, suggesting that the decolorizing activity was due to a protein. Decolorization activity of membrane fractions was stimulated by ferrous ion and inhibited by dinitrophenol and metyrapone. PMID:12821489

Transcriptome Analysis of Mycobacteria-Specific CD4+ T Cells Identified by Activation-Induced Expression of CD154.

Science.gov (United States)

Kunnath-Velayudhan, Shajo; Goldberg, Michael F; Saini, Neeraj K; Johndrow, Christopher T; Ng, Tony W; Johnson, Alison J; Xu, Jiayong; Chan, John; Jacobs, William R; Porcelli, Steven A

2017-10-01

Analysis of Ag-specific CD4 + T cells in mycobacterial infections at the transcriptome level is informative but technically challenging. Although several methods exist for identifying Ag-specific T cells, including intracellular cytokine staining, cell surface cytokine-capture assays, and staining with peptide:MHC class II multimers, all of these have significant technical constraints that limit their usefulness. Measurement of activation-induced expression of CD154 has been reported to detect live Ag-specific CD4 + T cells, but this approach remains underexplored and, to our knowledge, has not previously been applied in mycobacteria-infected animals. In this article, we show that CD154 expression identifies adoptively transferred or endogenous Ag-specific CD4 + T cells induced by Mycobacterium bovis bacillus Calmette-Guérin vaccination. We confirmed that Ag-specific cytokine production was positively correlated with CD154 expression by CD4 + T cells from bacillus Calmette-Guérin-vaccinated mice and show that high-quality microarrays can be performed from RNA isolated from CD154 + cells purified by cell sorting. Analysis of microarray data demonstrated that the transcriptome of CD4 + CD154 + cells was distinct from that of CD154 - cells and showed major enrichment of transcripts encoding multiple cytokines and pathways of cellular activation. One notable finding was the identification of a previously unrecognized subset of mycobacteria-specific CD4 + T cells that is characterized by the production of IL-3. Our results support the use of CD154 expression as a practical and reliable method to isolate live Ag-specific CD4 + T cells for transcriptomic analysis and potentially for a range of other studies in infected or previously immunized hosts. Copyright © 2017 by The American Association of Immunologists, Inc.

Macropinocytosis is responsible for the uptake of pathogenic and non-pathogenic mycobacteria by B lymphocytes (Raji cells

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García-Pérez Blanca Estela

2012-10-01

Full Text Available Abstract Background The classical roles of B cells include the production of antibodies and cytokines and the generation of immunological memory, these being key factors in the adaptive immune response. However, their role in innate immunity is currently being recognised. Traditionally, B cells have been considered non-phagocytic cells; therefore, the uptake of bacteria by B cells is not extensively documented. In this study, we analysed some of the features of non-specific bacterial uptake by B lymphocytes from the Raji cell line. In our model, B cells were infected with Mycobacterium tuberculosis (MTB, Mycobacterium smegmatis (MSM, and Salmonella typhimurium (ST. Results Our observations revealed that the Raji B cells were readily infected by the three bacteria that were studied. All of the infections induced changes in the cellular membrane during bacterial internalisation. M. smegmatis and S. typhimurium were able to induce important membrane changes that were characterised by abundant filopodia and lamellipodia formation. These membrane changes were driven by actin cytoskeletal rearrangements. The intracellular growth of these bacteria was also controlled by B cells. M. tuberculosis infection also induced actin rearrangement-driven membrane changes; however, the B cells were not able to control this infection. The phorbol 12-myristate 13-acetate (PMA treatment of B cells induced filopodia and lamellipodia formation, the production of spacious vacuoles (macropinosomes, and the fluid-phase uptake that is characteristic of macropinocytosis. S. typhimurium infection induced the highest fluid-phase uptake, although both mycobacteria also induced fluid uptake. A macropinocytosis inhibitor such as amiloride was used and abolished the bacterial uptake and the fluid-phase uptake that is triggered during the bacterial infection. Conclusions Raji B cells can internalise S. typhimurium and mycobacteria through an active process, such as

Beta-lactamases of Mycobacterium tuberculosis and Mycobacterium kansasii.

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Segura, C; Salvadó, M

1997-09-01

Re-emergence of infectious diseases caused by mycobacteria as well as the emergence of multiresistant strains of Mycobacterium has promoted the research on the use of beta-lactames in the treatment of such diseases. Mycobacteria produce beta-lactamases: M. tuberculosis produces a wide-spectrum beta-lactamase whose behaviour mimicks those of Gram-negative bacteria. M. kansasii produces also beta-lactamase which can be inhibited by clavulanic acid. An overview on beta-lactamases from both species is reported.

Rapid detection and identification of pathogenic mycobacteria by combining radiometric and nucleic acid probe methods

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Ellner, P.D.; Kiehn, T.E.; Cammarata, R.; Hosmer, M.

1988-01-01

The combination of radiometric methodology (BACTEC 12B) and probe technology for recovery and identification of mycobacteria was studied in two large hospital laboratories. The sediment from vials with positive growth indices was tested with DNA probes specific for Mycobacterium tuberculosis, Mycobacterium avium, and Mycobacterium intracellulare. The sensitivity of the radiometric method and the specificity of the probes resulted in a marked reduction in the time to the final report. Biochemical testing could be eliminated on isolates giving a positive reaction with one of the probes. Some 176 isolates of M. tuberculosis, 110 of M. avium, and 5 of M. intracellulare were recovered. Two-thirds of these isolates were detected and identified within 2 weeks of inoculation and the remainder was detected by 4 weeks, a reduction of 5 to 7 weeks to the final report

Counting mycobacteria in infected human cells and mouse tissue: a comparison between qPCR and CFU.

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Sharad Pathak

Full Text Available Due to the slow growth rate and pathogenicity of mycobacteria, enumeration by traditional reference methods like colony counting is notoriously time-consuming, inconvenient and biohazardous. Thus, novel methods that rapidly and reliably quantify mycobacteria are warranted in experimental models to facilitate basic research, development of vaccines and anti-mycobacterial drugs. In this study we have developed quantitative polymerase chain reaction (qPCR assays for simultaneous quantification of mycobacterial and host DNA in infected human macrophage cultures and in mouse tissues. The qPCR method cannot discriminate live from dead bacteria and found a 10- to 100-fold excess of mycobacterial genomes, relative to colony formation. However, good linear correlations were observed between viable colony counts and qPCR results from infected macrophage cultures (Pearson correlation coefficient [r] for M. tuberculosis = 0.82; M. a. avium = 0.95; M. a. paratuberculosis = 0.91. Regression models that predict colony counts from qPCR data in infected macrophages were validated empirically and showed a high degree of agreement with observed counts. Similar correlation results were also obtained in liver and spleen homogenates of M. a. avium infected mice, although the correlations were distinct for the early phase (< day 9 post-infection and later phase (≥ day 20 post-infection liver r = 0.94 and r = 0.91; spleen r = 0.91 and r = 0.87, respectively. Interestingly, in the mouse model the number of live bacteria as determined by colony counts constituted a much higher proportion of the total genomic qPCR count in the early phase (geometric mean ratio of 0.37 and 0.34 in spleen and liver, respectively, as compared to later phase of infection (geometric mean ratio of 0.01 in both spleen and liver. Overall, qPCR methods offer advantages in biosafety, time-saving, assay range and reproducibility compared to colony counting. Additionally, the duplex format allows

Disease caused by non-tuberculous mycobacteria: diagnostic procedures and treatment evaluation in the North of Buenos Aires Province

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Belén Imperiale

2012-03-01

Full Text Available Non-tuberculous mycobacteria (NTM have emerged as pathogens frequently associated to HIV co-infection. The aims of this study were to describe the clinical importance of NTM in patients from the North of Buenos Aires Province and the drug-susceptibility patterns in relation with the therapy used. A total of 23,624 clinical specimens were investigated during the period 2004-2010. Ziehl-Neelsen stain and cultures were used for diagnosis. Molecular and biochemical tests were performed to identify the mycobacteria. TB and mycobacterioses cases were 2 118 and 108 respectively. Sixteen NTM species were found: Mycobacterium avium and Mycobacterium intracellulare as the main causative agents. Infections produced by more than one species at the same time were confirmed (4 cases. Macrolides and fluoroquinolones were the most active in vitro drugs. Treatment evaluation showed that 68.0 % of the cases completed the therapy, 20 % died; and 12 % were relapses. The cases in which the treatment outcome was evaluated received an individual tailor-made therapeutic scheme including those drugs showing in vitro activity and presumed in vivo usefulness. More than a quarter of the patients had HIV co-infection and the majority of the deaths were associated with this co-infection.Enfermedad causada por micobacterias no tuberculosas: diagnóstico y evaluación del tratamiento en el norte del Gran Buenos Aires. Las micobacterias no tuberculosas (MNT emergieron como patógenos frecuentemente asociados a la co-infección con el HIV. EL objetivo del estudio fue describir la importancia clínica de las MNT en pacientes de la región norte de la provincia de Buenos Aires y los patrones de drogo-sensibilidad en relación con la terapia empleada. Se investigó un total de 23.624 especímenes clínicos durante, el período 2004-2010. La tinción de Ziehl-Neelsen y los cultivos se utilizaron para diagnóstico. Las micobacterias fueron identificadas mediante pruebas bioqu

Current Methods in the Molecular Typing of Mycobacterium tuberculosis and Other Mycobacteria

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van Ingen, Jakko; Dziadek, Jarosław; Mazur, Paweł K.; Bielecki, Jacek

2014-01-01

In the epidemiology of tuberculosis (TB) and nontuberculous mycobacterial (NTM) diseases, as in all infectious diseases, the key issue is to define the source of infection and to disclose its routes of transmission and dissemination in the environment. For this to be accomplished, the ability of discerning and tracking individual Mycobacterium strains is of critical importance. Molecular typing methods have greatly improved our understanding of the biology of mycobacteria and provide powerful tools to combat the diseases caused by these pathogens. The utility of various typing methods depends on the Mycobacterium species under investigation as well as on the research question. For tuberculosis, different methods have different roles in phylogenetic analyses and person-to-person transmission studies. In NTM diseases, most investigations involve the search for environmental sources or phylogenetic relationships. Here, too, the type of setting determines which methodology is most suitable. Within this review, we summarize currently available molecular methods for strain typing of M. tuberculosis and some NTM species, most commonly associated with human disease. For the various methods, technical practicalities as well as discriminatory power and accomplishments are reviewed. PMID:24527454

MALDI-TOF MS Andromas strategy for the routine identification of bacteria, mycobacteria, yeasts, Aspergillus spp. and positive blood cultures.

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Bille, E; Dauphin, B; Leto, J; Bougnoux, M-E; Beretti, J-L; Lotz, A; Suarez, S; Meyer, J; Join-Lambert, O; Descamps, P; Grall, N; Mory, F; Dubreuil, L; Berche, P; Nassif, X; Ferroni, A

2012-11-01

All organisms usually isolated in our laboratory are now routinely identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) using the Andromas software. The aim of this study was to describe the use of this strategy in a routine clinical microbiology laboratory. The microorganisms identified included bacteria, mycobacteria, yeasts and Aspergillus spp. isolated on solid media or extracted directly from blood cultures. MALDI-TOF MS was performed on 2665 bacteria isolated on solid media, corresponding to all bacteria isolated during this period except Escherichia coli grown on chromogenic media. All acquisitions were performed without extraction. After a single acquisition, 93.1% of bacteria grown on solid media were correctly identified. When the first acquisition was not contributory, a second acquisition was performed either the same day or the next day. After two acquisitions, the rate of bacteria identified increased to 99.2%. The failures reported on 21 strains were due to an unknown profile attributed to new species (9) or an insufficient quality of the spectrum (12). MALDI-TOF MS has been applied to 162 positive blood cultures. The identification rate was 91.4%. All mycobacteria isolated during this period (22) were correctly identified by MALDI-TOF MS without any extraction. For 96.3% and 92.2% of yeasts and Aspergillus spp., respectively, the identification was obtained with a single acquisition. After a second acquisition, the overall identification rate was 98.8% for yeasts (160/162) and 98.4% (63/64) for Aspergillus spp. In conclusion, the MALDI-TOF MS strategy used in this work allows a rapid and efficient identification of all microorganisms isolated routinely. © 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.

Flux through trehalose synthase flows from trehalose to the alpha anomer of maltose in mycobacteria.

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Miah, Farzana; Koliwer-Brandl, Hendrik; Rejzek, Martin; Field, Robert A; Kalscheuer, Rainer; Bornemann, Stephen

2013-04-18

Trehalose synthase (TreS) was thought to catalyze flux from maltose to trehalose, a precursor of essential trehalose mycolates in mycobacterial cell walls. However, we now show, using a genetic approach, that TreS is not required for trehalose biosynthesis in Mycobacterium smegmatis, whereas two alternative trehalose-biosynthetic pathways (OtsAB and TreYZ) are crucial. Consistent with this direction of flux, trehalose levels in Mycobacterium tuberculosis decreased when TreS was overexpressed. In addition, TreS was shown to interconvert the α anomer of maltose and trehalose using (1)H and (19)F-nuclear magnetic resonance spectroscopies using its normal substrates and deoxyfluoromaltose analogs, with the nonenzymatic mutarotation of α/β-maltose being slow. Therefore, flux through TreS in mycobacteria flows from trehalose to α-maltose, which is the appropriate anomer for maltose kinase of the GlgE α-glucan pathway, which in turn contributes to intracellular and/or capsular polysaccharide biosynthesis. Copyright © 2013 Elsevier Ltd. All rights reserved.

Differential effects of Radix Paeoniae Rubra (Chishao on cytokine and chemokine expression inducible by mycobacteria

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Li James

2011-03-01

Full Text Available Abstract Background Upon initial infection with mycobacteria, macrophages secrete multiple cytokines and chemokines, including interleukin-6 (IL-6, IL-8 and tumor necrosis factor-α (TNF-α, to mediate host immune responses against the pathogen. Mycobacteria also induce the production of IL-10 via PKR activation in primary human monocytes and macrophages. As an anti-inflammatory cytokine, over-expression of IL-10 may contribute to mycobacterial evasion of the host immunity. Radix Paeoniae Rubra (RPR, Chishao, a Chinese medicinal herb with potentials of anti-inflammatory, hepatoprotective and neuroprotective effects, is used to treat tuberculosis. This study investigates the immunoregulatory effects of RPR on primary human blood macrophages (PBMac during mycobacterial infection. Methods The interaction of Bacillus Calmette-Guerin (BCG with PBMac was used as an experimental model. A series of procedures involving solvent extraction and fractionation were used to isolate bioactive constituents in RPR. RPR-EA-S1, a fraction with potent immunoregulatory effects was obtained with a bioactivity guided fractionation scheme. PBMac were treated with crude RPR extracts or RPR-EA-S1 before BCG stimulation. The expression levels of IL-6, IL-8, IL-10 and TNF-α were measured by qPCR and ELISA. Western blotting was used to determine the effects of RPR-EA-S1 on signaling kinases and transcriptional factors in the BCG-activated PBMac. Results In BCG-stimulated macrophages, crude RPR extracts and fraction RPR-EA-S1 specifically inhibited IL-10 production while enhanced IL-8 expression at both mRNA and protein levels without affecting the expressions of IL-6 and TNF-α. Inhibition of BCG-induced IL-10 expression by RPR-EA-S1 occurred in a dose- and time-dependent manner. RPR-EA-S1 did not affect the phosphorylation of cellular protein kinases including MAPK, Akt and GSK3β. Instead, it suppressed the degradation of IκBα in the cytoplasm and inhibited the

Disseminated mycobacteria chelonae infection in a kidney-pancreas transplant recipient: A case report and review of the literature

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Shafi Malik

2016-01-01

Full Text Available A 40-year-old male with a long-standing history of type 1 diabetes with end-stage renal failure underwent combined kidney-pancreas (KP transplant from a standard criteria donor. Post-operative course was uncomplicated with good primary function of both transplant grafts. Induction was with thymoglobulin and maintenance immunosuppression was with tacrolimus, mycophenolate mofetil and prednisolone. Nine weeks post-transplant, the patient developed dysfunction of both grafts. Panel reactive antibody testing revealed that the patient had developed a de novo donor-specific antibody and considering an antibody-mediated rejection the patient was treated with intravenous pulse methyl prednisone 500 mg ×3 doses, IV immunoglobulin 2 mg/kg in two divided doses, and ATG 7 mg/kg (total dose of 700 mg. In addition, his baseline immunosuppression was increased. Cr decreased to baseline levels, and blood sugars were in the range of 7-8 mmol/L, serum amylase normalized to 63 U/L, and the patient was discharged home. Nine days post-discharge, the patient presented to the hospital with a five-day history of fever, pain, and swelling in the left knee along with subcutaneous, erythematous, tender, nodular lesions in both legs and both arms. Skin biopsy showed Ziehl-Neelsen stain positive rods and biopsy culture and blood culture grew Mycobacteria chelonae. Antimicrobials were switched to azithromycin 500 mg OD, moxifloxacin 400 mg OD, and linezolid 600 mg BID and baseline immunosuppression was reduced to tacrolimus trough target 8-10 ng/mL and MMF to 250 mg BID. The patient gradually improved and was discharged after 28 days in the hospital. Six weeks following the diagnosis of nontuberculous mycobacteria infection, the patient′s pancreas graft failed, presumably due to reduction in immuno-suppression and he is now back on insulin treatment. His renal graft continued to function well. Although rapidly growing mycobacterial infections are rare among transplant

Complete Genome Sequence of the Frog Pathogen Mycobacterium ulcerans Ecovar Liflandii

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Tobias, Nicholas J.; Doig, Kenneth D.; Medema, Marnix H.; Chen, Honglei; Haring, Volker; Moore, Robert; Seemann, Torsten; Stinear, Timothy P.

In 2004, a previously undiscovered mycobacterium resembling Mycobacterium ulcerans (the agent of Buruli ulcer) was reported in an outbreak of a lethal mycobacteriosis in a laboratory colony of the African clawed frog Xenopus tropicalis. This mycobacterium makes mycolactone and is one of several

Comparative Analyses of Nonpathogenic, Opportunistic, and Totally Pathogenic Mycobacteria Reveal Genomic and Biochemical Variabilities and Highlight the Survival Attributes of Mycobacterium tuberculosis

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Singh, Yadvir; Kohli, Sakshi; Ahmad, Javeed; Ehtesham, Nasreen Z.; Tyagi, Anil K.

2014-01-01

ABSTRACT Mycobacterial evolution involves various processes, such as genome reduction, gene cooption, and critical gene acquisition. Our comparative genome size analysis of 44 mycobacterial genomes revealed that the nonpathogenic (NP) genomes were bigger than those of opportunistic (OP) or totally pathogenic (TP) mycobacteria, with the TP genomes being smaller yet variable in size—their genomic plasticity reflected their ability to evolve and survive under various environmental conditions. From the 44 mycobacterial species, 13 species, representing TP, OP, and NP, were selected for genomic-relatedness analyses. Analysis of homologous protein-coding genes shared between Mycobacterium indicus pranii (NP), Mycobacterium intracellulare ATCC 13950 (OP), and Mycobacterium tuberculosis H37Rv (TP) revealed that 4,995 (i.e., ~95%) M. indicaus pranii proteins have homology with M. intracellulare, whereas the homologies among M. indicus pranii, M. intracellulare ATCC 13950, and M. tuberculosis H37Rv were significantly lower. A total of 4,153 (~79%) M. indicus pranii proteins and 4,093 (~79%) M. intracellulare ATCC 13950 proteins exhibited homology with the M. tuberculosis H37Rv proteome, while 3,301 (~82%) and 3,295 (~82%) M. tuberculosis H37Rv proteins showed homology with M. indicus pranii and M. intracellulare ATCC 13950 proteomes, respectively. Comparative metabolic pathway analyses of TP/OP/NP mycobacteria showed enzymatic plasticity between M. indicus pranii (NP) and M. intracellulare ATCC 13950 (OP), Mycobacterium avium 104 (OP), and M. tuberculosis H37Rv (TP). Mycobacterium tuberculosis seems to have acquired novel alternate pathways with possible roles in metabolism, host-pathogen interactions, virulence, and intracellular survival, and by implication some of these could be potential drug targets. PMID:25370496

Dehalogenation of Haloalkanes by Mycobacterium tuberculosis H37Rv and Other Mycobacteria

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Jesenská, Andrea; Sedlác̆ek, Ivo; Damborský, Jir̆í

2000-01-01

Haloalkane dehalogenases convert haloalkanes to their corresponding alcohols by a hydrolytic mechanism. To date, various haloalkane dehalogenases have been isolated from bacteria colonizing environments that are contaminated with halogenated compounds. A search of current databases with the sequences of these known haloalkane dehalogenases revealed the presence of three different genes encoding putative haloalkane dehalogenases in the genome of the human parasite Mycobacterium tuberculosis H37Rv. The ability of M. tuberculosis and several other mycobacterial strains to dehalogenate haloaliphatic compounds was therefore studied. Intact cells of M. tuberculosis H37Rv were found to dehalogenate 1-chlorobutane, 1-chlorodecane, 1-bromobutane, and 1,2-dibromoethane. Nine isolates of mycobacteria from clinical material and four strains from a collection of microorganisms were found to be capable of dehalogenating 1,2-dibromoethane. Crude extracts prepared from two of these strains, Mycobacterium avium MU1 and Mycobacterium smegmatis CCM 4622, showed broad substrate specificity toward a number of halogenated substrates. Dehalogenase activity in the absence of oxygen and the identification of primary alcohols as the products of the reaction suggest a hydrolytic dehalogenation mechanism. The presence of dehalogenases in bacterial isolates from clinical material, including the species colonizing both animal tissues and free environment, indicates a possible role of parasitic microorganisms in the distribution of degradation genes in the environment. PMID:10618227

Pulmonary infection with hypervirulent Mycobacteria reveals a crucial role for the P2X7 receptor in aggressive forms of tuberculosis.

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Eduardo P Amaral

2014-07-01

Full Text Available The purinergic P2X7 receptor (P2X7R is a sensor of extracellular ATP, a damage-associated molecule that is released from necrotic cells and that induces pro-inflammatory cytokine production and cell death. To investigate whether the innate immune response to damage signals could contribute to the development of pulmonary necrotic lesions in severe forms of tuberculosis, disease progression was examined in C57BL/6 and P2X7R-/- mice that were intratracheally infected with highly virulent mycobacterial strains (Mycobacterium tuberculosis strain 1471 of the Beijing genotype family and Mycobacterium bovis strain MP287/03. The low-dose infection of C57BL/6 mice with bacteria of these strains caused the rapid development of extensive granulomatous pneumonia with necrotic areas, intense bacillus dissemination and anticipated animal death. In contrast, in P2X7R-/- mice, the lung pathology presented with moderate infiltrates of mononuclear leukocytes without visible signs of necrosis; the disease attenuation was accompanied by a delay in mortality. In vitro, the hypervirulent mycobacteria grew rapidly inside macrophages and induced death by a P2X7R-dependent mechanism that facilitated the release of bacilli. Furthermore, these bacteria were resistant to the protective mechanisms elicited in macrophages following extracellular ATP stimulation. Based on this study, we propose that the rapid intracellular growth of hypervirulent mycobacteria results in massive macrophage damage. The ATP released by damaged cells engages P2X7R and accelerates the necrotic death of infected macrophages and the release of bacilli. This vicious cycle exacerbates pneumonia and lung necrosis by promoting widespread cell destruction and bacillus dissemination. These findings suggest the use of drugs that have been designed to inhibit the P2X7R as a new therapeutic approach to treat the aggressive forms of tuberculosis.

Detection of molecular markers by comparative sequence analysis of enzymes from mycobacteria species

International Nuclear Information System (INIS)

Asad, S.; Hussain, M.; Siddiqua, A.; Ain, Q.U.

2014-01-01

Mycobacterial species are one of the most important pathogens and among these members of non-tuberculous mycobacteria (NTM) and mycobacterial tuberculousis complex (MTC) are the causative agent of a relatively milder form of Tuberculosis. Traditional methods for identification of these groups of pathogens are time consuming, lack specificity and sensitivity and furthermore lead to the misidentification due to high similarity index. Therefore, more rapid, specific and cost-effective methods are required for the accurate identification of Mycobacterium species in routine diagnostics. In our study, we identified molecular markers in order to differentiate closely related cousin species of genus Mycobacterium including M. bovis, M. avium, M. leprae and M. tuberculosis. The nucleotide sequences of selected unique markers, i.e., enzymes (used previously in various biochemical tests for the identification of M. species) were selected and their ORFs were retrieved and selected functional proteins of respective biosynthetic pathways were compared in-silico. Result suggested that the variations in nucleotide sequences of the selected enzymes can be directly used for M. species discrimination in one step PCR test. We believe that the in-silico identification and storage of these distinctive characteristics of individual M. species will help in more precise recognition of pathogenic strains and hence specie specific targeted therapy. (author)

Control of biotin biosynthesis in mycobacteria by a pyruvate carboxylase dependent metabolic signal.

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Lazar, Nathaniel; Fay, Allison; Nandakumar, Madhumitha; Boyle, Kerry E; Xavier, Joao; Rhee, Kyu; Glickman, Michael S

2017-12-01

Biotin is an essential cofactor utilized by all domains of life, but only synthesized by bacteria, fungi and plants, making biotin biosynthesis a target for antimicrobial development. To understand biotin biosynthesis in mycobacteria, we executed a genetic screen in Mycobacterium smegmatis for biotin auxotrophs and identified pyruvate carboxylase (Pyc) as required for biotin biosynthesis. The biotin auxotrophy of the pyc::tn strain is due to failure to transcriptionally induce late stage biotin biosynthetic genes in low biotin conditions. Loss of bioQ, the repressor of biotin biosynthesis, in the pyc::tn strain reverted biotin auxotrophy, as did reconstituting the last step of the pathway through heterologous expression of BioB and provision of its substrate DTB. The role of Pyc in biotin regulation required its catalytic activities and could be supported by M. tuberculosis Pyc. Quantitation of the kinetics of depletion of biotinylated proteins after biotin withdrawal revealed that Pyc is the most rapidly depleted biotinylated protein and metabolomics revealed a broad metabolic shift in wild type cells upon biotin withdrawal which was blunted in cell lacking Pyc. Our data indicate that mycobacterial cells monitor biotin sufficiency through a metabolic signal generated by dysfunction of a biotinylated protein of central metabolism. © 2017 John Wiley & Sons Ltd.

Non-tuberculous mycobacteria: baseline data from three sites in Papua New Guinea, 2010-2012.

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Ley, Serej; Carter, Robyn; Millan, Korai; Phuanukoonnon, Suparat; Pandey, Sushil; Coulter, Christopher; Siba, Peter; Beck, Hans-Peter

2015-01-01

To determine the proportion of non-tuberculous mycobacteria (NTM) in samples of pulmonary tuberculosis (TB) cases from Papua New Guinea who were diagnosed using acid-fast microscopy. As part of a case detection study for TB, conducted in three provincial hospitals in Papua New Guinea, sputum samples of suspected tuberculous cases aged 15 years or older were collected from November 2010 to July 2012. Mycobacterial species isolated from sputum and grown in culture were examined to distinguish between NTM and the Mycobacterium tuberculosis complex (MTBC). NTM were detected in 4% (9/225) of sputum samples grown in culture. Five (2.2%) of them were identified as NTM only and four (1.8%) were identified as mixed cultures containing both MTBC and NTM. Four different NTM species were identified; M. fortuitum, M. intracellulare, M. terrae and M. avium. This is the first report from Papua New Guinea identifying NTM in three different locations. As NTM cannot be distinguished from M. tuberculosis through smear microscopy, the presence of NTM can lead to a false-positive diagnosis of tuberculosis. The prevalence of NTM should be determined and a diagnostic algorithm developed to confirm acid-fast bacilli in a smear as M. tuberculosis.

Mycobacteria exploit three genetically distinct DNA double-strand break repair pathways.

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Gupta, Richa; Barkan, Daniel; Redelman-Sidi, Gil; Shuman, Stewart; Glickman, Michael S

2011-01-01

Bacterial pathogens rely on their DNA repair pathways to resist genomic damage inflicted by the host. DNA double-strand breaks (DSBs) are especially threatening to bacterial viability. DSB repair by homologous recombination (HR) requires nucleases that resect DSB ends and a strand exchange protein that facilitates homology search. RecBCD and RecA perform these functions in Escherichia coli and constitute the major pathway of error-free DSB repair. Mycobacteria, including the human pathogen M. tuberculosis, elaborate an additional error-prone pathway of DSB repair via non-homologous end-joining (NHEJ) catalysed by Ku and DNA ligase D (LigD). Little is known about the relative contributions of HR and NHEJ to mycobacterial chromosome repair, the factors that dictate pathway choice, or the existence of additional DSB repair pathways. Here we demonstrate that Mycobacterium smegmatis has three DSB repair pathway options: HR, NHEJ and a novel mechanism of single-strand annealing (SSA). Inactivation of NHEJ or SSA is compensated by elevated HR. We find that mycobacterial RecBCD does not participate in HR or confer resistance to ionizing radiation (IR), but is required for the RecA-independent SSA pathway. In contrast, the mycobacterial helicase-nuclease AdnAB participates in the RecA-dependent HR pathway, and is a major determinant of resistance to IR and oxidative DNA damage. These findings reveal distinctive features of mycobacterial DSB repair, most notably the dedication of the RecBCD and AdnAB helicase-nuclease machines to distinct repair pathways. © 2010 Blackwell Publishing Ltd.

Characterization of non-tuberculosis mycobacteria by neutron radiography

International Nuclear Information System (INIS)

Silva, Jaqueline M. da; Crispim, Verginia Reis; Gomes da Silva, Marlei; Furtado, Vanessa Rodrigues; Duarte, Rafael Da Silva

2013-01-01

The genus Mycobacterium shares many characteristics with Corynebacterium and Actinomyces genera, among which the genomic guanine plus cytosine content and the production of long branched-chain fatty acids, known as mycolic acids are enhanced. Growth rate and optimal temperature of mycobacteria are variable. The genus comprises more than 140 known species; however Mycobacterium fortuitum, a fast growing nontuberculous mycobacterium, is clinically significant, because it has been associated to several lesions following surgery procedures such as liposuction, silicone breast and pacemaker implants, exposure to prosthetic materials besides sporadic lesions in the skin, soft tissues and rarely lungs. The objective of the present study is to reduce the time necessary for M. fortuitum characterization based on its morphology and the use of the neutron radiography technique substituting the classical biochemical assays. We also aim to confirm the utility of dendrimers as boron carriers. The samples were sterilized through conventional protocols using 10% formaldehyde. In the incubation process, two solutions with different molar ratios (10:1 and 20:1) of sodium borate and PAMAM G4 dendrimer and also pure sodium borate were used. After doping and sterilization procedures, the samples were deposited on CR-39 sheets, irradiated with a 4.6×10 5 n/cm 2 s thermal neutron flux for 30 min, from the J-9 irradiation channel of the Argonauta IEN/CNEN reactor. The images registered in the CR-39 were visualized in a Nikon E400 optical transmission microscope and captured by a Nikon Coolpix 995 digital camera. Developing the nuclear tracks registered in the CR-39 allowed a 1000× enlargement of mycobacterium images, facilitating their characterization, the use of more sophisticated equipment not being necessary. The use of neutron radiography technique reduced the time necessary for characterization. Doping with PAMAM dendrimer improved the visualization of NTM in neutron radiography

Capacity of lung stroma to educate dendritic cells inhibiting mycobacteria-specific T-cell response depends upon genetic susceptibility to tuberculosis.

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Kapina, Marina A; Rubakova, Elvira I; Majorov, Konstantin B; Logunova, Nadezhda N; Apt, Alexander S

2013-01-01

The balance between activation and inhibition of local immune responses in affected tissues during prolonged chronic infections is important for host protection. There is ample evidence that regulatory, tolerogenic dendritic cells (DC) are developed and present in tissues and inhibit overwhelming inflammatory reactions. Also, it was firmly established that stromal microenvironment of many organs is able to induce development of immature regulatory DC (DCreg), an essential element of a general immune regulatory network. However, direct experimental data demonstrating inhibition of immune responses by stroma-instructed immature DCreg in infectious models are scarce, and virtually nothing is known about functioning of this axis of immunity during tuberculosis (TB) infection. In this study, we demonstrate that lung stromal cells are capable of supporting the development in culture of immature CD11b(+)CD11c(low)CD103(-) DCreg from lineage-negative (lin(-)) bone marrow precursors. DCreg developed on lung stroma isolated from mice of genetically TB-hyper-susceptible I/St and relatively resistant B6 inbred strains inhibited proliferative response of mycobacteria-specific CD4(+) T-cell lines a dose-dependent manner. Importantly, the inhibitory activity of B6 DCreg was substantially higher than that of I/St Dcreg. Moreover, when the donors of stromal cells were chronically infected with virulent mycobacteria, the capacity to instruct inhibitory DCreg was retained in B6, but further diminished in I/St stromal cells. DCreg-provided suppression was mediated by a few soluble mediators, including PGE2, NO and IL-10. The content of CD4(+)Foxp3(+) Treg cells in the mediastinal, lung-draining lymph nodes at the advanced stages of chronic infection did not change in I/St, but increased 2-fold in B6 mice, and lung pathology was much more pronounced in the former mice. Taken together, these data provide genetic evidence that the capacity to maintain populations of regulatory cells

Capacity of lung stroma to educate dendritic cells inhibiting mycobacteria-specific T-cell response depends upon genetic susceptibility to tuberculosis.

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Marina A Kapina

Full Text Available The balance between activation and inhibition of local immune responses in affected tissues during prolonged chronic infections is important for host protection. There is ample evidence that regulatory, tolerogenic dendritic cells (DC are developed and present in tissues and inhibit overwhelming inflammatory reactions. Also, it was firmly established that stromal microenvironment of many organs is able to induce development of immature regulatory DC (DCreg, an essential element of a general immune regulatory network. However, direct experimental data demonstrating inhibition of immune responses by stroma-instructed immature DCreg in infectious models are scarce, and virtually nothing is known about functioning of this axis of immunity during tuberculosis (TB infection. In this study, we demonstrate that lung stromal cells are capable of supporting the development in culture of immature CD11b(+CD11c(lowCD103(- DCreg from lineage-negative (lin(- bone marrow precursors. DCreg developed on lung stroma isolated from mice of genetically TB-hyper-susceptible I/St and relatively resistant B6 inbred strains inhibited proliferative response of mycobacteria-specific CD4(+ T-cell lines a dose-dependent manner. Importantly, the inhibitory activity of B6 DCreg was substantially higher than that of I/St Dcreg. Moreover, when the donors of stromal cells were chronically infected with virulent mycobacteria, the capacity to instruct inhibitory DCreg was retained in B6, but further diminished in I/St stromal cells. DCreg-provided suppression was mediated by a few soluble mediators, including PGE2, NO and IL-10. The content of CD4(+Foxp3(+ Treg cells in the mediastinal, lung-draining lymph nodes at the advanced stages of chronic infection did not change in I/St, but increased 2-fold in B6 mice, and lung pathology was much more pronounced in the former mice. Taken together, these data provide genetic evidence that the capacity to maintain populations of regulatory

Comparison of the fibronectin-binding ability and antitumor efficacy of various mycobacteria.

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Hudson, M A; Ritchey, J K; Catalona, W J; Brown, E J; Ratliff, T L

1990-07-01

Although the mechanism by which Bacillus Calmette-Guerin (BCG) exerts an antitumor effect on superficial bladder tumors is not fully understood, recent evidence has implicated binding of BCG organisms to fibronectin (FN) as requisite for this antitumor efficacy. Various substrains of BCG and other mycobacteria were tested in vitro for their relative capacities to bind both matrix and soluble FN. A substrain of Mycobacterium kansasii, designated the "high-binding strain," was found to bind FN more readily (P less than 0.05) in in vitro studies, when compared to commercially available substrains of BCG (Tice, Connaught, and Armand Frappier). The binding by the three commercial strains of BCG to FN in vitro appeared to be equivalent. The high-binding strain was further demonstrated to attach more readily in vivo to the acutely injured murine bladder (P less than 0.005) than the Armand Frappier substrain. Finally, using the MB49 murine bladder tumor model, an enhanced antitumor effect (P less than 0.05) was noted in mice treated with intravesical high-binding strain, in comparison to the Armand Frappier substrain, during five weekly treatments. It appears not only that the commercial substrains of BCG bind FN in an equivalent manner but also that the relative binding capacities of the substrains correlate directly with antitumor activity. A substrain of M. kansasii appears to have been identified which may prove more clinically effective than the currently available strains of BCG.

Distinct mechanisms of DNA repair in mycobacteria and their implications in attenuation of the pathogen growth.

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Kurthkoti, Krishna; Varshney, Umesh

2012-04-01

About a third of the human population is estimated to be infected with Mycobacterium tuberculosis. Emergence of drug resistant strains and the protracted treatment strategies have compelled the scientific community to identify newer drug targets, and to develop newer vaccines. In the host macrophages, the bacterium survives within an environment rich in reactive nitrogen and oxygen species capable of damaging its genome. Therefore, for its successful persistence in the host, the pathogen must need robust DNA repair mechanisms. Analysis of M. tuberculosis genome sequence revealed that it lacks mismatch repair pathway suggesting a greater role for other DNA repair pathways such as the nucleotide excision repair, and base excision repair pathways. In this article, we summarize the outcome of research involving these two repair pathways in mycobacteria focusing primarily on our own efforts. Our findings, using Mycobacterium smegmatis model, suggest that deficiency of various DNA repair functions in single or in combinations severely compromises their DNA repair capacity and attenuates their growth under conditions typically encountered in macrophages. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Esters of pyrazinoic acid are active against pyrazinamide-resistant strains of Mycobacterium tuberculosis and other naturally resistant mycobacteria in vitro and ex vivo within macrophages.

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Pires, David

2015-10-05

Pyrazinamide (PZA) is active against major Mycobacterium tuberculosis species (M. tuberculosis, M. africanum, and M. microti), but not against M. bovis and M. avium. The latter two are mycobacteria species involved in human and cattle tuberculosis and in HIV co-infections, respectively. PZA is a first-line agent for the treatment of human tuberculosis and requires activation by a mycobacterial pyrazinamidase to form the active metabolite pyrazinoic acid (POA). As a result of this mechanism, resistance to PZA as often found in tuberculosis patients is caused by point mutations in pyrazinamidase. In previous work, we have shown that POA esters and amides synthesized in our laboratory were stable in plasma. Although the amides did not present significant activity, the esters were active against sensitive mycobacteria at concentrations 5-to-10 fold lower than those of PZA. Here, we report that these POA derivatives possess antibacterial efficacy in vitro and ex vivo against several species and strains of Mycobacterium with natural or acquired resistance to PZA, including M. bovis and M. avium. Our results indicate that the resistance was probably overcome by cleavage of the prodrugs into POA and a long-chain alcohol. Although it is not possible to rule out that the esters may have intrinsic activity per se, we bring evidence here that long-chain fatty alcohols possess a significant anti-mycobacterial effect against PZA-resistant species and strains and are not mere inactive promoieties. These findings may lead to candidate dual-drugs having enhanced activity against both PZA-susceptible and PZA-resistant isolates and being suitable for clinical development.

Clinical and taxonomic status of pathogenic nonpigmented or late-pigmenting rapidly growing mycobacteria.

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Brown-Elliott, Barbara A; Wallace, Richard J

2002-10-01

The history, taxonomy, geographic distribution, clinical disease, and therapy of the pathogenic nonpigmented or late-pigmenting rapidly growing mycobacteria (RGM) are reviewed. Community-acquired disease and health care-associated disease are highlighted for each species. The latter grouping includes health care-associated outbreaks and pseudo-outbreaks as well as sporadic disease cases. Treatment recommendations for each species and type of disease are also described. Special emphasis is on the Mycobacterium fortuitum group, including M. fortuitum, M. peregrinum, and the unnamed third biovariant complex with its recent taxonomic changes and newly recognized species (including M. septicum, M. mageritense, and proposed species M. houstonense and M. bonickei). The clinical and taxonomic status of M. chelonae, M. abscessus, and M. mucogenicum is also detailed, along with that of the closely related new species, M. immunogenum. Additionally, newly recognized species, M. wolinskyi and M. goodii, as well as M. smegmatis sensu stricto, are included in a discussion of the M. smegmatis group. Laboratory diagnosis of RGM using phenotypic methods such as biochemical testing and high-performance liquid chromatography and molecular methods of diagnosis are also discussed. The latter includes PCR-restriction fragment length polymorphism analysis, hybridization, ribotyping, and sequence analysis. Susceptibility testing and antibiotic susceptibility patterns of the RGM are also annotated, along with the current recommendations from the National Committee for Clinical Laboratory Standards (NCCLS) for mycobacterial susceptibility testing.

Drug Susceptibility Testing of 31 Antimicrobial Agents on Rapidly Growing Mycobacteria Isolates from China.

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Pang, Hui; Li, Guilian; Zhao, Xiuqin; Liu, Haican; Wan, Kanglin; Yu, Ping

2015-01-01

Several species of rapidly growing mycobacteria (RGM) are now recognized as human pathogens. However, limited data on effective drug treatments against these organisms exists. Here, we describe the species distribution and drug susceptibility profiles of RGM clinical isolates collected from four southern Chinese provinces from January 2005 to December 2012. Clinical isolates (73) were subjected to in vitro testing with 31 antimicrobial agents using the cation-adjusted Mueller-Hinton broth microdilution method. The isolates included 55 M. abscessus, 11 M. fortuitum, 3 M. chelonae, 2 M. neoaurum, and 2 M. septicum isolates. M. abscessus (75.34%) and M. fortuitum (15.07%), the most common species, exhibited greater antibiotic resistance than the other three species. The isolates had low resistance to amikacin, linezolid, and tigecycline, and high resistance to first-line antituberculous agents, amoxicillin-clavulanic acid, rifapentine, dapsone, thioacetazone, and pasiniazid. M. abscessus and M. fortuitum were highly resistant to ofloxacin and rifabutin, respectively. The isolates showed moderate resistance to the other antimicrobial agents. Our results suggest that tigecycline, linezolid, clofazimine, and cefmetazole are appropriate choices for M. abscessus infections. Capreomycin, sulfamethoxazole, tigecycline, clofazimine, and cefmetazole are potentially good choices for M. fortuitum infections. Our drug susceptibility data should be useful to clinicians.

Drug Susceptibility Testing of 31 Antimicrobial Agents on Rapidly Growing Mycobacteria Isolates from China

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Hui Pang

2015-01-01

Full Text Available Objectives. Several species of rapidly growing mycobacteria (RGM are now recognized as human pathogens. However, limited data on effective drug treatments against these organisms exists. Here, we describe the species distribution and drug susceptibility profiles of RGM clinical isolates collected from four southern Chinese provinces from January 2005 to December 2012. Methods. Clinical isolates (73 were subjected to in vitro testing with 31 antimicrobial agents using the cation-adjusted Mueller-Hinton broth microdilution method. The isolates included 55 M. abscessus, 11 M. fortuitum, 3 M. chelonae, 2 M. neoaurum, and 2 M. septicum isolates. Results. M. abscessus (75.34% and M. fortuitum (15.07%, the most common species, exhibited greater antibiotic resistance than the other three species. The isolates had low resistance to amikacin, linezolid, and tigecycline, and high resistance to first-line antituberculous agents, amoxicillin-clavulanic acid, rifapentine, dapsone, thioacetazone, and pasiniazid. M. abscessus and M. fortuitum were highly resistant to ofloxacin and rifabutin, respectively. The isolates showed moderate resistance to the other antimicrobial agents. Conclusions. Our results suggest that tigecycline, linezolid, clofazimine, and cefmetazole are appropriate choices for M. abscessus infections. Capreomycin, sulfamethoxazole, tigecycline, clofazimine, and cefmetazole are potentially good choices for M. fortuitum infections. Our drug susceptibility data should be useful to clinicians.

Microculture in biphasic medium with silicone-coated slides for isolation of mycobacteria.

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Shibayama, H; Galván, F J; Contreras, C

1996-09-01

The study reported here, seeking to develop a simple, practical, sensitive, and inexpensive technique for microbial diagnosis of tuberculosis, used a combination of biphasic media and microculture techniques to augment the sensitivity of traditional culture methods. A total of 540 sputum samples (5 mL each) were obtained from 180 patients with suspected tuberculosis in Mexico City. These samples were treated with Hanks reagent, neutralized with 25% HCl, and centrifuged. In each case the resulting residue was combined with liquid media (Sula medium or a phosphate-buffered control solution) and was inoculated into a bottle containing a solid medium (Löwenstein-Jensen-Holm or Middlebrook). A silicone-coated slide appropriate for culture of hydrophobic mycobacteria was inserted in each bottle, and the cultures (examined weekly) were incubated at 37 degrees C until the first macroscopic bacterial growth was detected or for up to eight weeks if none was detected. When such growth was detected, or at the end of eight weeks, each slide was withdrawn from the bottle, sterilized, stained by Kinyoun's method, and examined microscopically. Following 2-4 weeks of incubation, macroscopic bacterial growth was detected in 71 bottles and was confirmed by microscopic examination of the corresponding slides. No macroscopic bacterial growth was found in any of the remaining 469 bottles, but microscopic growth was observed on 77 of the slides examined after eight weeks. The authors conclude that this method represents a noteworthy improvement over standard culture methods in terms of bacterial isolation and suggest that its case, economy, and practicality make it suitable for application in developing countries.

Biofilm colonization in chronic treatment refractory infections presenting with discharging sinuses: A study in a tertiary care hospital of Eastern India

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Asmita De

2017-01-01

Conclusion: AFM has been proven to be a useful method for detection of in vitro grown BF including those for anaerobes and atypical Mycobacteria. In vivo BF detection becomes possible by FISH. S. aureus was the most common isolate. Among the aerobic isolates, P. aeruginosa and S. epidermidis were found to be the most common BF producers. Atypical mycobacteria were also found to be BF producers. Diagnosis of BF s in chronic infections significantly changes the management strategy as these infections can no longer be dealt simply with antibiotics alone but require mechanical removal of the foci along with antibiotic coverage for complete cure.

Non-tuberculous mycobacteria: baseline data from three sites in Papua New Guinea, 2010–2012

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Ley, Serej; Carter, Robyn; Millan, Korai; Phuanukoonnon, Suparat; Pandey, Sushil; Coulter, Christopher; Siba, Peter

2015-01-01

Objective To determine the proportion of non-tuberculous mycobacteria (NTM) in samples of pulmonary tuberculosis (TB) cases from Papua New Guinea who were diagnosed using acid-fast microscopy. Methods As part of a case detection study for TB, conducted in three provincial hospitals in Papua New Guinea, sputum samples of suspected tuberculous cases aged 15 years or older were collected from November 2010 to July 2012. Mycobacterial species isolated from sputum and grown in culture were examined to distinguish between NTM and the Mycobacterium tuberculosis complex (MTBC). Results NTM were detected in 4% (9/225) of sputum samples grown in culture. Five (2.2%) of them were identified as NTM only and four (1.8%) were identified as mixed cultures containing both MTBC and NTM. Four different NTM species were identified; M. fortuitum, M. intracellulare, M. terrae and M. avium. Discussion This is the first report from Papua New Guinea identifying NTM in three different locations. As NTM cannot be distinguished from M. tuberculosis through smear microscopy, the presence of NTM can lead to a false-positive diagnosis of tuberculosis. The prevalence of NTM should be determined and a diagnostic algorithm developed to confirm acid-fast bacilli in a smear as M. tuberculosis. PMID:26798558

Acidic methanolysis v. alkaline saponification in gas chromatographic characterization of mycobacteria: differentiation between Mycobacterium avium-intracellulare and Mycobacterium gastri.

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Larsson, L

1983-08-01

Mycobacterium avium-intracellulare and M.gastri were analyzed with capillary gas chromatography after each strain had been subjected to acidic methanolysis or to alkaline saponification followed by methylation. Prominent peaks of myristic, palmitoleic, palmitic, oleic, stearic and tuberculostearic acids were found in the chromatograms of both species, whereas 2-octadecanol and 2-eicosanol were detected only in M. avium-intracellulare. In initial runs, both of the derivatization principles yielded virtually identical chromatograms for a given strain. After repeated injections of extracts from alkaline saponification, however, the alcohol peaks showed pronounced tailing and finally almost disappeared from the chromatograms. This disadvantage, which was not observed when only acid methanolysis was used, could be overcome with trifluoroacetylation. Restored peak shape of the underivatized alcohols could be achieved by washing the cross-linked stationary phase in the capillary tubing with organic solvents. The study demonstrated the importance of conditions which enable separation of 2-octadecanol and 2-eicosanol when gas chromatography is used for species identification of mycobacteria.

Surveillance of Tuberculosis in Taipei: The Influence of Nontuberculous Mycobacteria.

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Chen-Yuan Chiang

Full Text Available Notification of tuberculosis (TB but not nontuberculous mycobacteria (NTM is mandatory in Taiwan. Partly due to the strict regulation on TB notification, several patients infected with NTM were notified as TB cases. Notification of patients infected with NTM as TB cases can trigger public health actions and impose additional burdens on the public health system. We conducted a study to assess the influence of NTM infection on surveillance of TB in Taipei.The study population included all individuals with a positive culture for Mycobacterium who were citizens of Taipei City and notified as TB cases in the calendar years 2007-2010. Of the 4216 notified culture-positive tuberculosis (TB cases, 894 (21.2% were infected with NTM. The average annual reported case rate of infection with NTM was 8.6 (95% confidence interval 7.7-9.4 per 100,000 people. The reported case rate of NTM increased with age in both males and females. The proportion of reported TB cases infected with NTM was significantly higher in females than in males (27.6% vs 17.8%, adjusted OR (adjOR 1.93, 95% confidence interval (CI 1.63-2.28; in smear-positive than in smear-negative (23.1% vs 19.2%, adjOR 1.26, 95% CI 1.08-1.47; and in previously treated cases than in new cases (35.7% vs 19.1%, adjOR 2.30, 95% CI 1.88-2.82. The most frequent species was M. avium complex (32.4%, followed by M. chelonae complex (17.6%, M. fortuitum complex (17.0% and M. kansasii (9.8%. Of the 890 notified NTM cases assessed, 703 (79.0% were treated with anti-TB drugs, and 730 (82.0% were de-notified.The influence of NTM on surveillance of TB in Taipei was substantial. Health authorities should take action to ensure that nucleic acid amplification tests are performed in all smear-positive cases in a timely manner to reduce the misdiagnosis of patients infected with NTM as TB cases.

Surveillance of Tuberculosis in Taipei: The Influence of Nontuberculous Mycobacteria.

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Chiang, Chen-Yuan; Yu, Ming-Chih; Yang, Shiang-Lin; Yen, Muh-Yong; Bai, Kuan-Jen

2015-01-01

Notification of tuberculosis (TB) but not nontuberculous mycobacteria (NTM) is mandatory in Taiwan. Partly due to the strict regulation on TB notification, several patients infected with NTM were notified as TB cases. Notification of patients infected with NTM as TB cases can trigger public health actions and impose additional burdens on the public health system. We conducted a study to assess the influence of NTM infection on surveillance of TB in Taipei. The study population included all individuals with a positive culture for Mycobacterium who were citizens of Taipei City and notified as TB cases in the calendar years 2007-2010. Of the 4216 notified culture-positive tuberculosis (TB) cases, 894 (21.2%) were infected with NTM. The average annual reported case rate of infection with NTM was 8.6 (95% confidence interval 7.7-9.4) per 100,000 people. The reported case rate of NTM increased with age in both males and females. The proportion of reported TB cases infected with NTM was significantly higher in females than in males (27.6% vs 17.8%, adjusted OR (adjOR) 1.93, 95% confidence interval (CI) 1.63-2.28); in smear-positive than in smear-negative (23.1% vs 19.2%, adjOR 1.26, 95% CI 1.08-1.47); and in previously treated cases than in new cases (35.7% vs 19.1%, adjOR 2.30, 95% CI 1.88-2.82). The most frequent species was M. avium complex (32.4%), followed by M. chelonae complex (17.6%), M. fortuitum complex (17.0%) and M. kansasii (9.8%). Of the 890 notified NTM cases assessed, 703 (79.0%) were treated with anti-TB drugs, and 730 (82.0%) were de-notified. The influence of NTM on surveillance of TB in Taipei was substantial. Health authorities should take action to ensure that nucleic acid amplification tests are performed in all smear-positive cases in a timely manner to reduce the misdiagnosis of patients infected with NTM as TB cases.

Rapid-Growing Mycobacteria Infections in Medical Tourists: Our Experience and Literature Review.

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Singh, Mansher; Dugdale, Caitlin M; Solomon, Isaac H; Huang, Anne; Montgomery, Mary W; Pomahac, Bohdan; Yawetz, Sigal; Maguire, James H; Talbot, Simon G

2016-09-01

"Medical tourism" has gained popularity over the past few decades. This is particularly common with patients seeking elective cosmetic surgery in the developing world. However, the risk of severe and unusual infectious complications appears to be higher than for patients undergoing similar procedures in the United States. The authors describe their experience with atypical mycobacterial infections in cosmetic surgical patients returning to the United States postoperatively. A review of patient medical records presenting with infectious complications after cosmetic surgery between January 2010 and July 2015 was performed. Patients presenting with mycobacterial infections following cosmetic surgery were reviewed in detail. An extensive literature review was performed for rapid-growing mycobacteria (RGM) related to cosmetic procedures. Between January 2010 and July 2015, three patients presented to our institution with culture-proven Mycobacterium abscessus at the sites of recent cosmetic surgery. All had surgery performed in the developing world. The mean age of these patients was 36 years (range, 29-44 years). There was a delay of up to 16 weeks between the initial presentation and correct diagnosis. All patients were treated with surgical drainage and combination antibiotics with complete resolution. We present series of patients with mycobacterial infections after cosmetic surgery in the developing world. This may be related to the endemic nature of these bacteria and/or inadequate sterilization or sterile technique. Due to low domestic incidence of these infections, diagnosis may be difficult and/or delayed. Consulting physicians should have a low threshold to consider atypical etiologies in such scenarios. 5 Therapeutic. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

Non-Tuberculous Mycobacteria multispecies biofilms in cystic fibrosis: development of an in vitro Mycobacterium abscessus and Pseudomonas aeruginosa dual species biofilm model.

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Rodríguez-Sevilla, Graciela; García-Coca, Marta; Romera-García, David; Aguilera-Correa, John Jairo; Mahíllo-Fernández, Ignacio; Esteban, Jaime; Pérez-Jorge, Concepción

2018-04-01

Lung disease in cystic fibrosis (CF) is characterized by the progressive colonization of the respiratory tract by different bacteria, which develop polymicrobial biofilms. In the past decades, there has been an increase in the number of CF patients infected with Non-Tuberculous Mycobacteria (NTM). Although Mycobacterium abscessus is the main NTM isolated globally, little is known about M. abscessus multispecies biofilm formation. In the present study we developed an in vitro model to study the phenotypic characteristics of biofilms formed by M. abscessus and Pseudomonas aeruginosa, a major pathogen in CF. For that purpose, dual species biofilms were grown on polycarbonate membranes with a fixed concentration of P. aeruginosa and different inoculums of M. abscessus. The biofilms were sampled at 24, 48, and 72 h and bacteria were quantified in specific media. The results revealed that the increasing initial concentration of M. abscessus in dual species biofilms had an effect on its population only at 24 and 48 h, whereas P. aeruginosa was not affected by the different concentrations used of M. abscessus. Time elapsed increased biofilm formation of both species, specially between 24 and 48 h. According to the results, the conditions to produce a mature dual species biofilm in which the relative species distribution remained stable were 72 h growth of the mixed microbial culture at a 1:1 ratio. A significant decrease in mycobacterial population in dual compared to single species biofilms was found, suggesting that P. aeruginosa has a negative influence on M. abscessus. Finally, in a proof of concept experiment, young and mature dual species biofilms were exposed to clarithromycin. Copyright © 2018 Elsevier GmbH. All rights reserved.

High Rates of Non-Tuberculous Mycobacteria Isolation in Mozambican Children with Presumptive Tuberculosis.

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Elisa López-Varela

Full Text Available Non-tuberculous mycobacteria (NTM can cause disease which can be clinically and radiologically undistinguishable from tuberculosis (TB, posing a diagnostic and therapeutic challenge in high TB settings. We aim to describe the prevalence of NTM isolation and its clinical characteristics in children from rural Mozambique.This study was part of a community TB incidence study in children <3 years of age. Gastric aspirate and induced sputum sampling were performed in all presumptive TB cases and processed for smear testing using fluorochrome staining and LED Microscopy, liquid and solid culture, and molecular identification by GenoType® Mycobacterium CM/AS assays.NTM were isolated in 26.3% (204/775 of children. The most prevalent NTM species was M. intracellulare (N = 128, followed by M. scrofulaceum (N = 35 and M. fortuitum (N = 9. Children with NTM were significantly less symptomatic and less likely to present with an abnormal chest radiograph than those with M. tuberculosis. NTM were present in 21.6% of follow-up samples and 25 children had the same species isolated from ≥2 separate samples. All were considered clinically insignificant and none received specific treatment. Children with NTM isolates had equal all cause mortality and likelihood of TB treatment as those with negative culture although they were less likely to have TB ruled out.NTM isolation is frequent in presumptive TB cases but was not clinically significant in this patient cohort. However, it can contribute to TB misdiagnosis. Further studies are needed to understand the epidemiology and the clinical significance of NTM in children.

Comparison of manual mycobacteria growth indicator tube and epsilometer test with agar proportion method for susceptibility testing of Mycobacterium tuberculosis

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N Karabulut

2014-01-01

Full Text Available Background and Objectives: Antimycobacterial susceptibility tests take weeks, and delayed therapy can lead to spread of Mycobacterium tuberculosis. Therefore, rapid, accurate and cost-effective methods are required for proper therapy selection. In this study, the Mycobacteria growth indicator tube (MGIT and epsilometer test (Etest methods were compared to the agar proportion method for susceptibility testing of Mycobacterium tuberculosis. Materials and Methods: The susceptibility tests against isoniazid (INH, rifampin (RIF, streptomycin (STM and ethambutol (ETM of 51 M. tuberculosis complex isolates were analyzed by the MGIT, Etest and agar proportion methods. Results: The concordance between MGIT/Etest and agar proportion methods was 98% for INH and 100% for RIF, STM, ETM. There were not statistically significant differences in results of the susceptibility tests between MGIT/Etest and the reference agar proportion method. Conclusion: The results have shown that MGIT and Etest methods can be used instead of the agar proportion method, because these two methods are more rapid and easier than the agar proportion method.

Molecular identification of nontuberculous mycobacteria isolated from pyogenic bovine tissues in South Darfur State and Alsabalouga slaughterhouse at Omdurman area, Sudan

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A.E. El Tigani-Asil

2014-02-01

Full Text Available This study identified nontuberculous mycobacteria (NTM recovered from bovine pyogenic affections obtained at necropsy using the molecular target 16S-23S rDNA internal transcribed spacer region. Postmortem inspection of cattle was conducted at South Darfur State abattoirs and Alsabalouga Slaughterhouse at Omdurman area during 2007-2009. Specimens were examined for the presence of acid fast bacteria (AFB using microscopic and standard culturing techniques. AFB were identified phenotypically and confirmed by 16S-23S rDNA ITS. Fifty nine NTM were recovered and confirmed as acid fast filaments out of 165 positive AFB specimens, of which 52 isolates were identified as bovine farcy causative agents, while 7 cultures were excluded due to drying. 16S-23S rDNA ITS of NTM revealed three different amplicons 500 bp. (32 isolates, 550 bp. (2 isolates and 600 bp. (14 isolates. Four isolates were contaminated.

Molecular identification of nontuberculous mycobacteria isolated from pyogenic bovine tissues in South Darfur State and Alsabalouga slaughterhouse at Omdurman area, Sudan.

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Tigani-Asil, A E El; Sanousi, S M El; Aljameel, M A; Beir, H El; Adam, A; Abdallatif, M M; Hamid, M E

2014-01-01

This study identified nontuberculous mycobacteria (NTM) recovered from bovine pyogenic affections obtained at necropsy using the molecular target 16S-23S rDNA internal transcribed spacer region. Postmortem inspection of cattle was conducted at South Darfur State abattoirs and Alsabalouga Slaughterhouse at Omdurman area during 2007-2009. Specimens were examined for the presence of acid fast bacteria (AFB) using microscopic and standard culturing techniques. AFB were identified phenotypically and confirmed by 16S-23S rDNA ITS. Fifty nine NTM were recovered and confirmed as acid fast filaments out of 165 positive AFB specimens, of which 52 isolates were identified as bovine farcy causative agents, while 7 cultures were excluded due to drying. 16S-23S rDNA ITS of NTM revealed three different amplicons 500 bp. (32) isolates, 550 bp. (2) isolates and 600 bp. (14) isolates. Four isolates were contaminated.

The epidemiology of pulmonary nontuberculous mycobacteria: data from a general hospital in Athens, Greece, 2007-2013.

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Panagiotou, Marios; Papaioannou, Andriana I; Kostikas, Konstantinos; Paraskeua, Maria; Velentza, Ekaterini; Kanellopoulou, Maria; Filaditaki, Vasiliki; Karagiannidis, Napoleon

2014-01-01

The epidemiology of pulmonary nontuberculous mycobacteria (NTM) in Greece is largely unknown. To determine the incidence and the demographic, microbiological, and clinical characteristics of patients with pulmonary NTM infection and pulmonary NTM disease. A retrospective review of the demographic, microbiological, and clinical characteristics of patients with NTM culture-positive respiratory specimens from January 2007 to May 2013. A total of 120 patients were identified with at least one respiratory NTM isolate and 56 patients (46%) fulfilled the microbiological ATS/IDSA criteria for NTM disease. Of patients with adequate data, 16% fulfilled the complete ATS/IDSA criteria for NTM disease. The incidence of pulmonary NTM infection and disease was 18.9 and 8.8 per 100.000 inpatients and outpatients, respectively. The spectrum of NTM species was high (13 species) and predominated by M. avium-intracellulare complex (M. avium (13%), M. intracellulare (10%)), M. gordonae (14%), and M. fortuitum (12%). The ratio of isolation of NTM to M. tuberculosis in all hospitalized patients was 0.59. The first data on the epidemiology of pulmonary NTM in Athens, Greece, are presented. NTM infection is common in patients with chronic respiratory disease. However, only a significantly smaller proportion of patients fulfill the criteria for NTM disease.

Mutation of environmental mycobacteria to resist silver nanoparticles also confers resistance to a common antibiotic.

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Larimer, Curtis; Islam, Mohammad Shyful; Ojha, Anil; Nettleship, Ian

2014-08-01

Non-tuberculous mycobacteria are a threat to human health, gaining entry to the body through contaminated water systems, where they form persistent biofilms despite extensive attempts at disinfection. Silver is a natural antibacterial agent and in nanoparticle form activity is increased by a high surface area. Silver nanoparticles (AgNPs) have been used as alternative disinfectants in circulating water systems, washing machines and even clothing. However, nanoparticles, like any other antibiotic that has a pervasive durable presence, carry the risk of creating a resistant population. In this study Mycobacterium smegmatis strain mc(2)155 was cultured in AgNP enriched agar such that only a small population survived. Surviving cultures were isolated and re-exposed to AgNPs and AgNO3 and resistance to silver was compared to a negative control. After only a single exposure, mutant M. smegmatis populations were resistant to AgNPs and AgNO3. Further, the silver resistant mutants were exposed to antibiotics to determine if general resistance had been conferred. The minimum inhibitory concentration of isoniazid was four times higher for silver resistant mutants than for strain mc(2)155. However, core resistance was not conferred to other toxic metal ions. The mutants had lower resistance to CuSO4 and ZnSO4 than the mc(2)155 strain.

Validation of biomarkers for distinguishing Mycobacterium tuberculosis from non-tuberculous mycobacteria using gas chromatography-mass spectrometry and chemometrics.

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Ngoc A Dang

Full Text Available Tuberculosis (TB remains a major international health problem. Rapid differentiation of Mycobacterium tuberculosis complex (MTB from non-tuberculous mycobacteria (NTM is critical for decisions regarding patient management and choice of therapeutic regimen. Recently we developed a 20-compound model to distinguish between MTB and NTM. It is based on thermally assisted hydrolysis and methylation gas chromatography-mass spectrometry and partial least square discriminant analysis. Here we report the validation of this model with two independent sample sets, one consisting of 39 MTB and 17 NTM isolates from the Netherlands, the other comprising 103 isolates (91 MTB and 12 NTM from Stellenbosch, Cape Town, South Africa. All the MTB strains in the 56 Dutch samples were correctly identified and the model had a sensitivity of 100% and a specificity of 94%. For the South African samples the model had a sensitivity of 88% and specificity of 100%. Based on our model, we have developed a new decision-tree that allows the differentiation of MTB from NTM with 100% accuracy. Encouraged by these findings we will proceed with the development of a simple, rapid, affordable, high-throughput test to identify MTB directly in sputum.

The Epidemiology of Pulmonary Nontuberculous Mycobacteria: Data from a General Hospital in Athens, Greece, 2007–2013

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Papaioannou, Andriana I.; Paraskeua, Maria; Velentza, Ekaterini; Kanellopoulou, Maria; Filaditaki, Vasiliki; Karagiannidis, Napoleon

2014-01-01

Background. The epidemiology of pulmonary nontuberculous mycobacteria (NTM) in Greece is largely unknown. Objectives. To determine the incidence and the demographic, microbiological, and clinical characteristics of patients with pulmonary NTM infection and pulmonary NTM disease. Methods. A retrospective review of the demographic, microbiological, and clinical characteristics of patients with NTM culture-positive respiratory specimens from January 2007 to May 2013. Results. A total of 120 patients were identified with at least one respiratory NTM isolate and 56 patients (46%) fulfilled the microbiological ATS/IDSA criteria for NTM disease. Of patients with adequate data, 16% fulfilled the complete ATS/IDSA criteria for NTM disease. The incidence of pulmonary NTM infection and disease was 18.9 and 8.8 per 100.000 inpatients and outpatients, respectively. The spectrum of NTM species was high (13 species) and predominated by M. avium-intracellulare complex (M. avium (13%), M. intracellulare (10%)), M. gordonae (14%), and M. fortuitum (12%). The ratio of isolation of NTM to M. tuberculosis in all hospitalized patients was 0.59. Conclusions. The first data on the epidemiology of pulmonary NTM in Athens, Greece, are presented. NTM infection is common in patients with chronic respiratory disease. However, only a significantly smaller proportion of patients fulfill the criteria for NTM disease. PMID:25132991

Performance comparison between the mycobacteria growth indicator tube system and Löwenstein-Jensen medium in the routine detection of Mycobacterium tuberculosis at public health care facilities in Rio de Janeiro, Brazil: preliminary results of a pragmatic clinical trial.

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Moreira, Adriana da Silva Rezende; Huf, Gisele; Vieira, Maria Armanda; Fonseca, Leila; Ricks, Monica; Kritski, Afrânio Lineu

2013-01-01

In view of the fact that the World Health Organization has recommended the use of the mycobacteria growth indicator tube (MGIT) 960 system for the diagnosis of tuberculosis and that there is as yet no evidence regarding the clinical impact of its use in health care systems, we conducted a pragmatic clinical trial to evaluate the clinical performance and cost-effectiveness of the use of MGIT 960 at two health care facilities in the city of Rio de Janeiro, Brazil, where the incidence of tuberculosis is high. Here, we summarize the methodology and preliminary results of the trial. (ISRCTN.org Identifier: ISRCTN79888843 [http://isrctn.org/]) In view of the fact that the World Health Organization has recommended the use of the mycobacteria growth indicator tube (MGIT) 960 system for the diagnosis of tuberculosis and that there is as yet no evidence regarding the clinical impact of its use in health care systems, we conducted a pragmatic clinical trial to evaluate the clinical performance and cost-effectiveness of the use of MGIT 960 at two health care facilities in the city of Rio de Janeiro, Brazil, where the incidence of tuberculosis is high. Here, we summarize the methodology and preliminary results of the trial. (ISRCTN.org Identifier: ISRCTN79888843 [http://isrctn.org/]).

Unique flexibility in energy metabolism allows mycobacteria to combat starvation and hypoxia.

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Michael Berney

Full Text Available Mycobacteria are a group of obligate aerobes that require oxygen for growth, but paradoxically have the ability to survive and metabolize under hypoxia. The mechanisms responsible for this metabolic plasticity are unknown. Here, we report on the adaptation of Mycobacterium smegmatis to slow growth rate and hypoxia using carbon-limited continuous culture. When M. smegmatis is switched from a 4.6 h to a 69 h doubling time at a constant oxygen saturation of 50%, the cells respond through the down regulation of respiratory chain components and the F1Fo-ATP synthase, consistent with the cells lower demand for energy at a reduced growth rate. This was paralleled by an up regulation of molecular machinery that allowed more efficient energy generation (i.e. Complex I and the use of alternative electron donors (e.g. hydrogenases and primary dehydrogenases to maintain the flow of reducing equivalents to the electron transport chain during conditions of severe energy limitation. A hydrogenase mutant showed a 40% reduction in growth yield highlighting the importance of this enzyme in adaptation to low energy supply. Slow growing cells at 50% oxygen saturation subjected to hypoxia (0.6% oxygen saturation responded by switching on oxygen scavenging cytochrome bd, proton-translocating cytochrome bc1-aa3 supercomplex, another putative hydrogenase, and by substituting NAD+-dependent enzymes with ferredoxin-dependent enzymes thus highlighting a new pattern of mycobacterial adaptation to hypoxia. The expression of ferredoxins and a hydrogenase provides a potential conduit for disposing of and transferring electrons in the absence of exogenous electron acceptors. The use of ferredoxin-dependent enzymes would allow the cell to maintain a high carbon flux through its central carbon metabolism independent of the NAD+/NADH ratio. These data demonstrate the remarkable metabolic plasticity of the mycobacterial cell and provide a new framework for understanding their

In-vitro antimycobacterial drug susceptibility testing of non-tubercular mycobacteria by tetrazolium microplate assay.

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Sankar, Manimuthu Mani; Gopinath, Krishnamoorthy; Singla, Roopak; Singh, Sarman

2008-07-11

Non-tubercular mycobacteria (NTM) has not been given due attention till the recent epidemic of HIV. This has led to increasing interest of health care workers in their biology, epidemiology and drug resistance. However, timely detection and drug susceptibility profiling of NTM isolates are always difficult in resource poor settings like India. Furthermore, no standardized methodology or guidelines are available to reproduce the results with clinical concordance. To find an alternative and rapid method for performing the drug susceptibility assay in a resource limited settings like India, we intended to evaluate the utility of Tetrazolium microplate assay (TEMA) in comparison with proportion method for reporting the drug resistance in clinical isolates of NTM. A total of fifty-five NTM isolates were tested for susceptibility against Streptomycin, Rifampicin, Ethambutol, Ciprofloxacin, Ofloxacin, Azithromycin, and Clarithromycin by TEMA and the results were compared with agar proportion method (APM). Of the 55 isolates, 23 (41.8%) were sensitive to all the drugs and the remaining 32 (58.2%) were resistant to at least one drug. TEMA had very good concordance with APM except with minor discrepancies. Susceptibility results were obtained in the median of 5 to 9 days by TEMA. The NTM isolates were highly sensitive against Ofloxacin (98.18% sensitive) and Ciprofloxacin (90.09% sensitive). M. mucogenicum was sensitive only to Clarithromycin and resistant to all the other drugs tested. The concordance between TEMA and APM ranged between 96.4 - 100%. Tetrazolium Microplate Assay is a rapid and highly reproducible method. However, it must be performed only in tertiary level Mycobacteriology laboratories with proper bio-safety conditions.

THE CELLS WITH MYCOBACTERIA IN GRANULOMATOUS AGGREGATES FROM MICE WITH LATENT TUBERCULOUS INFECTION IN EX VIVO CULTURE

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E. G. Ufimtseva

2013-01-01

Full Text Available Abstract. The aim of this study was to obtain ex vivo monolayer culture cells migrated from individual granulomas isolated from the spleens of the Balb/c line mice through 1–2 months after BCG vaccine infection. The second goal was to evaluate influence of different types of cells in the development of granulomatic inflammation and analysis of BCG bacteria content in these cells in the latent stage of tuberculosis. Granulomas were presented by macrophages in general. The number of granulomas was varied as in one mouse as between mice. Granulomas contained also dendritic cells (in average 10% from macrophages of granulomas and lymphocytes. In some granulomas fibroblasts, neutrophils, eosiniphils, multinuclear cells of Pirogov–Langhans, megacariocytes and platelets were observed in all stages of infection. The number of these cells was also varied between granulomas. The acid staining BCG bacteria were only detected in macrophages, dendritic cells and Pirogov–Langhans cells of mice granulomas. Mice were different as by number of cells with BCG bacteria in granulomas as by number of granulomas with BCG-containing cells. The proposed model of granuloma cells of mice in ex vivo culture can be used to study interaction between host cells and mycobacteria to find new ways and methods of influence to intracellular pathogens in latent stage of tuberculosis. 

Nontuberculous mycobacteria in respiratory samples from patients with pulmonary tuberculosis in the state of Rondonia, Brazil

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Cleoni Alves Mendes de Lima

2013-06-01

Full Text Available The main cause of pulmonary tuberculosis (TB is infection with Mycobacterium tuberculosis (MTB. We aimed to evaluate the contribution of nontuberculous mycobacteria (NTM to pulmonary disease in patients from the state of Rondônia using respiratory samples and epidemiological data from TB cases. Mycobacterium isolates were identified using a combination of conventional tests, polymerase chain reaction-based restriction enzyme analysis of hsp65 gene and hsp65 gene sequencing. Among the 1,812 cases suspected of having pulmonary TB, 444 yielded bacterial cultures, including 369 cases positive for MTB and 75 cases positive for NTM. Within the latter group, 14 species were identified as Mycobacterium abscessus, Mycobacterium avium, Mycobacterium fortuitum, Mycobacterium intracellulare, Mycobacterium gilvum, Mycobacterium gordonae, Mycobacterium asiaticum, Mycobacterium tusciae, Mycobacterium porcinum, Mycobacterium novocastrense, Mycobacterium simiae, Mycobacterium szulgai, Mycobacterium phlei and Mycobacterium holsaticum and 13 isolates could not be identified at the species level. The majority of NTM cases were observed in Porto Velho and the relative frequency of NTM compared with MTB was highest in Ji-Paraná. In approximately half of the TB subjects with NTM, a second sample containing NTM was obtained, confirming this as the disease-causing agent. The most frequently observed NTM species were M. abscessus and M. avium and because the former species is resistant to many antibiotics and displays unsatisfactory cure rates, the implementation of rapid identification of mycobacterium species is of considerable importance.

Morphologic characterization of Mycobacterium marinum by neutron radiographic technique

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Silva, Jaqueline Michele da; Crispim, Verginia Reis, E-mail: vrcrispim@gmail.com [Universidade Federal do Rio de Janeiro (CT/UFRJ) Centro Tecnologico, Engenharia Nuclear, RJ (Brazil); Silva, Marlei Gomes da [Universidade Federal do Rio de Janeiro (CCS/UFRJ), Centro de Ciencias da Saude. Instituto de Microbiologia Professor Paulo de Goes (Brazil)

2011-07-01

The genus Mycobacterium shares many characteristics with the genera Corynebacterium and Actinomyces, among which, similar genome content of bases Guanine-Cytosine and the production of branched long-chain fatty acids called mycolic acids should be enhanced. Mycobacteria are strict aerobic, considered weakly Gram-positive, rod-shaped microorganisms, not possessing flagella. They are intracellular infecting and proliferating in the interior of macrophages, they do not form spores, produce toxins or have capsule. Optimal growth temperature and rate are variable. The genus encompasses approximately 120 known species; however, the present study focuses the characterization of Mycobacterium marinum. This species is generally pathogenic causing deep skin infections. Colonies grow slowly at temperatures around 37 degree C. The aim of this study is to speed the process of M. Marinum morphologic characterization and, in the future, apply it to other species of Nontuberculous Mycobacteria (NTM. In relation to conventional microbiologic essays that usually demand 28 days for colony growth, nuclear testing, using the neutron radiography technique, prove to be much faster. The samples were initially sterilized at the Mycobacteria Laboratory/IMPPG/UFRJ using hypochlorite solution, gluta + formaldehyde and warmed distilled water, according conventional protocols. Then, they were incubated with sodium borate, deposited over CR-39 sheets, fixed with casein (only the first and third sample) and irradiated with a thermal neutron beam generated at the J-9 channel of the Argonauta reactor from the IEN/CNEN. To this end, the following parameters were optimized: incubation time, irradiation time and CR-39 developing time. The images registered in CR-39 were visualized with the help of a Nikon E-400 optical microscope and captured with a Cool pix 995 digital camera. The results showed that the technique produces enlarged images, making it easier the morphologic characterization of

Morphologic characterization of Mycobacterium marinum by neutron radiographic technique

International Nuclear Information System (INIS)

Silva, Jaqueline Michele da; Crispim, Verginia Reis; Silva, Marlei Gomes da

2011-01-01

The genus Mycobacterium shares many characteristics with the genera Corynebacterium and Actinomyces, among which, similar genome content of bases Guanine-Cytosine and the production of branched long-chain fatty acids called mycolic acids should be enhanced. Mycobacteria are strict aerobic, considered weakly Gram-positive, rod-shaped microorganisms, not possessing flagella. They are intracellular infecting and proliferating in the interior of macrophages, they do not form spores, produce toxins or have capsule. Optimal growth temperature and rate are variable. The genus encompasses approximately 120 known species; however, the present study focuses the characterization of Mycobacterium marinum. This species is generally pathogenic causing deep skin infections. Colonies grow slowly at temperatures around 37 degree C. The aim of this study is to speed the process of M. Marinum morphologic characterization and, in the future, apply it to other species of Nontuberculous Mycobacteria (NTM. In relation to conventional microbiologic essays that usually demand 28 days for colony growth, nuclear testing, using the neutron radiography technique, prove to be much faster. The samples were initially sterilized at the Mycobacteria Laboratory/IMPPG/UFRJ using hypochlorite solution, gluta + formaldehyde and warmed distilled water, according conventional protocols. Then, they were incubated with sodium borate, deposited over CR-39 sheets, fixed with casein (only the first and third sample) and irradiated with a thermal neutron beam generated at the J-9 channel of the Argonauta reactor from the IEN/CNEN. To this end, the following parameters were optimized: incubation time, irradiation time and CR-39 developing time. The images registered in CR-39 were visualized with the help of a Nikon E-400 optical microscope and captured with a Cool pix 995 digital camera. The results showed that the technique produces enlarged images, making it easier the morphologic characterization of

Rapid Reagentless Detection of M. tuberculosis H37Ra in Respiratory Effluents

International Nuclear Information System (INIS)

Adams, K.L.; Steele, P.T.; Bogan, M.J.; Sadler, N.M.; Martin, S.; Martin, A.N.; Frank, M.

2008-01-01

Two similar mycobacteria, Mycobacteria tuberculosis H37Ra and Mycobacteria smegmatis are rapidly detected and identified within samples containing a complex background of respiratory effluents using Single Particle Aerosol Mass Spectrometry (SPAMS). M. tuberculosis H37Ra (TBa), an avirulent strain, is used as a surrogate for virulent tuberculosis (TBv); M. smegmatis (MSm) is utilized as a near neighbor confounder for TBa. Bovine lung surfactant and human exhaled breath condensate are used as first-order surrogates for infected human lung expirations from patients with pulmonary tuberculosis. This simulated background sputum is mixed with TBa or MSm and nebulized to produce conglomerate aerosol particles, single particles that contain a bacterium embedded within a background respiratory matrix. Mass spectra of single conglomerate particles exhibit ions associated with both respiratory effluents and mycobacteria. Spectral features distinguishing TBa from MSm in pure and conglomerate particles are shown. SPAMS pattern matching alarm algorithms are able to distinguish TBa containing particles from background matrix and MSm for >50% of the test particles, which is sufficient to enable a high probability of detection and a low false alarm rate if an adequate number of such particles are present. These results indicate the potential usefulness of SPAMS for rapid, reagentless tuberculosis screening

Rapid Reagentless Detection of M. tuberculosis H37Ra in Respiratory Effluents

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Adams, K L; Steele, P T; Bogan, M J; Sadler, N M; Martin, S; Martin, A N; Frank, M

2008-01-29

Two similar mycobacteria, Mycobacteria tuberculosis H37Ra and Mycobacteria smegmatis are rapidly detected and identified within samples containing a complex background of respiratory effluents using Single Particle Aerosol Mass Spectrometry (SPAMS). M. tuberculosis H37Ra (TBa), an avirulent strain, is used as a surrogate for virulent tuberculosis (TBv); M. smegmatis (MSm) is utilized as a near neighbor confounder for TBa. Bovine lung surfactant and human exhaled breath condensate are used as first-order surrogates for infected human lung expirations from patients with pulmonary tuberculosis. This simulated background sputum is mixed with TBa or MSm and nebulized to produce conglomerate aerosol particles, single particles that contain a bacterium embedded within a background respiratory matrix. Mass spectra of single conglomerate particles exhibit ions associated with both respiratory effluents and mycobacteria. Spectral features distinguishing TBa from MSm in pure and conglomerate particles are shown. SPAMS pattern matching alarm algorithms are able to distinguish TBa containing particles from background matrix and MSm for >50% of the test particles, which is sufficient to enable a high probability of detection and a low false alarm rate if an adequate number of such particles are present. These results indicate the potential usefulness of SPAMS for rapid, reagentless tuberculosis screening.

Comparative trials with different decontaminating agents for growing Mycobacterium tuberculosis from sputum specimens.

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Sula, L

1968-01-01

A reliable culture technique for mycobacteria to enable precise taxonomic and biological identification to be made, e.g., virulence and sensitivity or resistance to the major and minor antituberculosis drugs, is one of the basic requirements of efficient and economic tuberculosis control measures. Several of the methods employed for this purpose have been studied systematically. Many of these methods make use of various detergents, especially quaternary ammonium bases in different combinations, which possess strong bacteriostatic or bacteriocidal properties and decontaminate sputum samples without, however, affecting the viability of mycobacteria.A series of experiments to study the effect of sodium lauryl sulfate and of pancreatin, both in combination with sodium hydroxide, and of a new detergent, di-isobutal-naphthalin-sulfonate (Nekal Bx) on the growth of mycobacteria in liquid and solid media were carried out. As a control technique, the processing of samples of pathological material with hydrochloric acid and sodium hydroxide was studied.On the basis of these experiments, the sodium lauryl sulfate method proved to be promising, both for the rapid growth and characterization of the colonies, and for producing the lowest contamination rate in cultures. However, none of the 4 techniques was sensitive enough under the experimental conditions to demonstrate mycobacteria in sputum samples containing few organisms.

Immunogenetic determinants of susceptibility/resistance to Mycobacterium ulcerans infection: a population based study – Benin biological bank on Buruli ulcer

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Capela, Carlos Alberto Pereira

2016-01-01

Tese de Doutoramento - Doutoramento em Medicina Buruli ulcer (BU) is an infectious disease found in tropical regions of Africa, America, Asia, and Australia. Most of the cases are reported in West Africa and BU is considered a neglected tropical disease by the World Health Organization (WHO). This necrotising skin infection is caused by Mycobacterium ulcerans that secretes the exotoxin mycolactone as its main virulence factor. There is emerging evidence for a major role of g...

Oral Tolerance to Environmental Mycobacteria Interferes with Intradermal, but Not Pulmonary, Immunization against Tuberculosis.

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Dominique N Price

2016-05-01

Full Text Available Bacille Calmette-Guérin (BCG is currently the only approved vaccine against tuberculosis (TB and is administered in over 150 countries worldwide. Despite its widespread use, the vaccine has a variable protective efficacy of 0-80%, with the lowest efficacy rates in tropical regions where TB is most prevalent. This variability is partially due to ubiquitous environmental mycobacteria (EM found in soil and water sources, with high EM prevalence coinciding with areas of poor vaccine efficacy. In an effort to elucidate the mechanisms underlying EM interference with BCG vaccine efficacy, we exposed mice chronically to Mycobacterium avium (M. avium, a specific EM, by two different routes, the oral and intradermal route, to mimic human exposure. After intradermal BCG immunization in mice exposed to oral M. avium, we saw a significant decrease in the pro-inflammatory cytokine IFN-γ, and an increase in T regulatory cells and the immunosuppressive cytokine IL-10 compared to naïve BCG-vaccinated animals. To circumvent the immunosuppressive effect of oral M. avium exposure, we vaccinated mice by the pulmonary route with BCG. Inhaled BCG immunization rescued IFN-γ levels and increased CD4 and CD8 T cell recruitment into airways in M. avium-presensitized mice. In contrast, intradermal BCG vaccination was ineffective at T cell recruitment into the airway. Pulmonary BCG vaccination proved protective against Mtb infection regardless of previous oral M. avium exposure, compared to intradermal BCG immunization. In conclusion, our data indicate that vaccination against TB by the pulmonary route increases BCG vaccine efficacy by avoiding the immunosuppressive interference generated by chronic oral exposure to EM. This has implications in TB-burdened countries where drug resistance is on the rise and health care options are limited due to economic considerations. A successful vaccine against TB is necessary in these areas as it is both effective and economical.

Mycobacteria attenuate nociceptive responses by formyl peptide receptor triggered opioid peptide release from neutrophils.

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Heike L Rittner

2009-04-01

Full Text Available In inflammation, pain is regulated by a balance of pro- and analgesic mediators. Analgesic mediators include opioid peptides which are secreted by neutrophils at the site of inflammation, leading to activation of opioid receptors on peripheral sensory neurons. In humans, local opioids and opioid peptides significantly downregulate postoperative as well as arthritic pain. In rats, inflammatory pain is induced by intraplantar injection of heat inactivated Mycobacterium butyricum, a component of complete Freund's adjuvant. We hypothesized that mycobacterially derived formyl peptide receptor (FPR and/or toll like receptor (TLR agonists could activate neutrophils, leading to opioid peptide release and inhibition of inflammatory pain. In complete Freund's adjuvant-induced inflammation, thermal and mechanical nociceptive thresholds of the paw were quantified (Hargreaves and Randall-Selitto methods, respectively. Withdrawal time to heat was decreased following systemic neutrophil depletion as well as local injection of opioid receptor antagonists or anti-opioid peptide (i.e. Met-enkephalin, beta-endorphin antibodies indicating an increase in pain. In vitro, opioid peptide release from human and rat neutrophils was measured by radioimmunoassay. Met-enkephalin release was triggered by Mycobacterium butyricum and formyl peptides but not by TLR-2 or TLR-4 agonists. Mycobacterium butyricum induced a rise in intracellular calcium as determined by FURA loading and calcium imaging. Opioid peptide release was blocked by intracellular calcium chelation as well as phosphoinositol-3-kinase inhibition. The FPR antagonists Boc-FLFLF and cyclosporine H reduced opioid peptide release in vitro and increased inflammatory pain in vivo while TLR 2/4 did not appear to be involved. In summary, mycobacteria activate FPR on neutrophils, resulting in tonic secretion of opioid peptides from neutrophils and in a decrease in inflammatory pain. Future therapeutic strategies may aim

Heterogeneous Family of Cyclomodulins: Smart Weapons That Allow Bacteria to Hijack the Eukaryotic Cell Cycle and Promote Infections

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Rachid A. El-Aouar Filho

2017-05-01

Full Text Available Some bacterial pathogens modulate signaling pathways of eukaryotic cells in order to subvert the host response for their own benefit, leading to successful colonization and invasion. Pathogenic bacteria produce multiple compounds that generate favorable conditions to their survival and growth during infection in eukaryotic hosts. Many bacterial toxins can alter the cell cycle progression of host cells, impairing essential cellular functions and impeding host cell division. This review summarizes current knowledge regarding cyclomodulins, a heterogeneous family of bacterial effectors that induce eukaryotic cell cycle alterations. We discuss the mechanisms of actions of cyclomodulins according to their biochemical properties, providing examples of various cyclomodulins such as cycle inhibiting factor, γ-glutamyltranspeptidase, cytolethal distending toxins, shiga toxin, subtilase toxin, anthrax toxin, cholera toxin, adenylate cyclase toxins, vacuolating cytotoxin, cytotoxic necrotizing factor, Panton-Valentine leukocidin, phenol soluble modulins, and mycolactone. Special attention is paid to the benefit provided by cyclomodulins to bacteria during colonization of the host.

In Vitro Comparison of Ertapenem, Meropenem, and Imipenem against Isolates of Rapidly Growing Mycobacteria and Nocardia by Use of Broth Microdilution and Etest.

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Brown-Elliott, Barbara A; Killingley, Jessica; Vasireddy, Sruthi; Bridge, Linda; Wallace, Richard J

2016-06-01

We compared the activities of the carbapenems ertapenem, meropenem, and imipenem against 180 isolates of rapidly growing mycobacteria (RGM) and 170 isolates of Nocardia using the Clinical and Laboratory Standards Institute (CLSI) guidelines. A subset of isolates was tested using the Etest. The rate of susceptibility to ertapenem and meropenem was limited and less than that to imipenem for the RGM. Analysis of major and minor discrepancies revealed that >90% of the isolates of Nocardia had higher MICs by the broth microdilution method than by Etest, in contrast to the lower broth microdilution MICs seen for >80% of the RGM. Imipenem remains the most active carbapenem against RGM, including Mycobacterium abscessus subsp. abscessus For Nocardia, imipenem was significantly more active only against Nocardia farcinica Although there may be utility in testing the activities of the newer carbapenems against Nocardia, their activities against the RGM should not be routinely tested. Testing by Etest is not recommended by the CLSI. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Differences between Mycobacterium-Host Cell Relationships in Latent Tuberculous Infection of Mice Ex Vivo and Mycobacterial Infection of Mouse Cells In Vitro

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Elena Ufimtseva

2016-01-01

Full Text Available The search for factors that account for the reproduction and survival of mycobacteria, including vaccine strains, in host cells is the priority for studies on tuberculosis. A comparison of BCG-mycobacterial loads in granuloma cells obtained from bone marrow and spleens of mice with latent tuberculous infection and cells from mouse bone marrow and peritoneal macrophage cultures infected with the BCG vaccine in vitro has demonstrated that granuloma macrophages each normally contained a single BCG-Mycobacterium, while those acutely infected in vitro had increased mycobacterial loads and death rates. Mouse granuloma cells were observed to produce the IFNγ, IL-1α, GM-CSF, CD1d, CD25, CD31, СD35, and S100 proteins. None of these activation markers were found in mouse cell cultures infected in vitro or in intact macrophages. Lack of colocalization of lipoarabinomannan-labeled BCG-mycobacteria with the lysosomotropic LysoTracker dye in activated granuloma macrophages suggests that these macrophages were unable to destroy BCG-mycobacteria. However, activated mouse granuloma macrophages could control mycobacterial reproduction in cells both in vivo and in ex vivo culture. By contrast, a considerable increase in the number of BCG-mycobacteria was observed in mouse bone marrow and peritoneal macrophages after BCG infection in vitro, when no expression of the activation-related molecules was detected in these cells.

Comparative trials with different decontaminating agents for growing Mycobacterium tuberculosis from culture specimens

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Šula, L.

1968-01-01

A reliable culture technique for mycobacteria to enable precise taxonomic and biological identification to be made, e.g., virulence and sensitivity or resistance to the major and minor antituberculosis drugs, is one of the basic requirements of efficient and economic tuberculosis control measures. Several of the methods employed for this purpose have been studied systematically. Many of these methods make use of various detergents, especially quaternary ammonium bases in different combinations, which possess strong bacteriostatic or bacteriocidal properties and decontaminate sputum samples without, however, affecting the viability of mycobacteria. A series of experiments to study the effect of sodium lauryl sulfate and of pancreatin, both in combination with sodium hydroxide, and of a new detergent, di-isobutal-naphthalin-sulfonate (Nekal Bx) on the growth of mycobacteria in liquid and solid media were carried out. As a control technique, the processing of samples of pathological material with hydrochloric acid and sodium hydroxide was studied. On the basis of these experiments, the sodium lauryl sulfate method proved to be promising, both for the rapid growth and characterization of the colonies, and for producing the lowest contamination rate in cultures. However, none of the 4 techniques was sensitive enough under the experimental conditions to demonstrate mycobacteria in sputum samples containing few organisms. ImagesFIG. 3FIG. 4FIG. 1FIG. 2 PMID:4978931

Clinical Relevance of Nontuberculous Mycobacteria Isolated from Sputum in a Gold Mining Workforce in South Africa: An Observational, Clinical Study

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Clare L. van Halsema

2015-01-01

Full Text Available Background. The clinical relevance of nontuberculous mycobacteria (NTM, detected by liquid more than solid culture in sputum specimens from a South African mining workforce, is uncertain. We aimed to describe the current spectrum and relevance of NTM in this population. Methods. An observational study including individuals with sputum NTM isolates, recruited at workforce tuberculosis screening and routine clinics. Symptom questionnaires were administered at the time of sputum collection and clinical records and chest radiographs reviewed retrospectively. Results. Of 232 individuals included (228 (98% male, median age 44 years, M. gordonae (60 individuals, M. kansasii (50, and M. avium complex (MAC: 38 were the commonest species. Of 38 MAC isolates, only 2 (5.3% were from smear-positive sputum specimens and 30/38 grew in liquid but not solid culture. MAC was especially prevalent among symptomatic, HIV-positive individuals. HIV prevalence was high: 57/74 (77% among those tested. No differences were found in probability of death or medical separation by NTM species. Conclusions. M. gordonae, M. kansasii, and MAC were the commonest NTM among miners with suspected tuberculosis, with most MAC from smear-negative specimens in liquid culture only. HIV testing and identification of key pathogenic NTM in this setting are essential to ensure optimal treatment.

Effects of mycobacteria major secretion protein, Ag85B, on allergic inflammation in the lung.

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Yusuke Tsujimura

Full Text Available Many epidemiological studies have suggested that the recent increase in prevalence and severity of allergic diseases such as asthma is inversely correlated with Mycobacterium bovis bacillus Calmette Guerin (BCG vaccination. However, the underlying mechanisms by which mycobacterial components suppress allergic diseases are not yet fully understood. Here we showed the inhibitory mechanisms for development of allergic airway inflammation by using highly purified recombinant Ag85B (rAg85B, which is one of the major protein antigens secreted from M. tuberculosis. Ag85B is thought to be a single immunogenic protein that can elicit a strong Th1-type immune response in hosts infected with mycobacteria, including individuals vaccinated with BCG. Administration of rAg85B showed a strong inhibitory effect on the development of allergic airway inflammation with induction of Th1-response and IL-17and IL-22 production. Both cytokines induced by rAg85B were involved in the induction of Th17-related cytokine-production innate immune cells in the lung. Administration of neutralizing antibodies to IL-17 or IL-22 in rAg85B-treated mice revealed that IL-17 induced the infiltration of neutrophils in BAL fluid and that allergen-induced bronchial eosinophilia was inhibited by IL-22. Furthermore, enhancement of the expression of genes associated with tissue homeostasis and wound healing was observed in bronchial tissues after rAg85B administration in a Th17-related cytokine dependent manner. The results of this study provide evidence for the potential usefulness of rAg85B as a novel approach for anti-allergic effect and tissue repair other than the role as a conventional TB vaccine.

[Nicotinamidase and the so-called pyrazinamidase in mycobacteria; the simultaneous occurrence of both activites (author's transl)].

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Tarnok, I; Pechmann, H; Krallmann-Wenzel, U; Röhrscheidt, E; Tarnok, Z

1979-07-01

Nicotin- and the so-called pyrazinamidase (in the following: "pyrazinamidase") have been found in strains of four mycobacteria species, M. fortuitum, M. gastri, M. bovis and M. microti. These findings are in contradiction to those summarized in Bergey's Manual of Determinative Bacteriology (1974). The reason for the discrepancies is that the original method (Bönicke, 1961) for amidase determination has not taken the following aspects into consideration: a) The inducibility of the nicotin- and "pyrazinamidase" (example: M. fortuitum); b) The temperature sensitivity of these enzymes (M. gastri); c) The light sensitivity of nicotinamidase (in photochromogenic M. gastri strains); d) The optimal substrate concentration which must be at least 4 mM instead of 0,8 mm. The following consequences can be drawn for the taxonomy and biochemistry of the tested organisms: e) The species status of M. gastri should be annuled. The main difference between M. gastri and M. kansasii consists only of the non-agglutinability of M. gastri by anti-M. kansasii serum. "Pyrazinamidase" and also nitrate reductase (Tarnok et al., in press) are positive in strains of both species; f) M. bovis possesses nicotin- and "pyrazinamidase" as M. tuberculosis too. Thus, these two species are more closely related than suggested earlier; g) Till now, no Mycobacterium has been found showing nicotinamidase without "pyrazinamidase" activity (or vice versa). It seems to be very probable that nicotinamidase, an enzyme of low substrate specificity, is able to hydrolyze several compounds with a nicotinamide-like structure such as pyrazinamide. Thus, we suggest the annulment of the term pyrazinamidase or the employment of quotation marks ("pyrazinamidase") to show the fictitious value of this designation.

Two novel species of rapidly growing mycobacteria: Mycobacterium lehmannii sp. nov. and Mycobacterium neumannii sp. nov.

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Nouioui, Imen; Sangal, Vartul; Carro, Lorena; Teramoto, Kanae; Jando, Marlen; Montero-Calasanz, Maria Del Carmen; Igual, José Mariano; Sutcliffe, Iain; Goodfellow, Michael; Klenk, Hans-Peter

2017-12-01

Two rapidly growing mycobacteria with identical 16S rRNA gene sequences were the subject of a polyphasic taxonomic study. The strains formed a well-supported subclade in the mycobacterial 16S rRNA gene tree and were most closely associated with the type strain of Mycobacterium novocastrense. Single and multilocus sequence analyses based on hsp65, rpoB and 16S rRNA gene sequences showed that strains SN 1900 T and SN 1904 T are phylogenetically distinct but share several chemotaxonomic and phenotypic features that are are consistent with their classification in the genus Mycobacterium. The two strains were distinguished by their different fatty acid and mycolic acid profiles, and by a combination of phenotypic features. The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values for strains SN 1900 T and SN 1904 T were 61.0 % and 94.7 %, respectively; in turn, the corresponding dDDH and ANI values with M. novocastrense DSM 44203 T were 41.4 % and 42.8 % and 89.3 % and 89.5 %, respectively. These results show that strains SN1900 T and SN 1904 T form new centres of taxonomic variation within the genus Mycobacterium. Consequently, strains SN 1900 T (40 T =CECT 8763 T =DSM 43219 T ) and SN 1904 T (2409 T =CECT 8766 T =DSM 43532 T ) are considered to represent novel species, for which the names Mycobacteriumlehmannii sp. nov. and Mycobacteriumneumannii sp. nov. are proposed. A strain designated as 'Mycobacteriumacapulsensis' was shown to be a bona fide member of the putative novel species, M. lehmannii.

Mycobacterium lutetiense sp. nov., Mycobacterium montmartrense sp. nov. and Mycobacterium arcueilense sp. nov., members of a novel group of non-pigmented rapidly growing mycobacteria recovered from a water distribution system.

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Konjek, Julie; Souded, Sabiha; Guerardel, Yann; Trivelli, Xavier; Bernut, Audrey; Kremer, Laurent; Welte, Benedicte; Joyeux, Michel; Dubrou, Sylvie; Euzeby, Jean-Paul; Gaillard, Jean-Louis; Sapriel, Guillaume; Heym, Beate

2016-09-01

From our recent survey of non-pigmented rapidly growing mycobacteria in the Parisian water system, three groups of isolates (taxons 1-3) corresponding to possible novel species were selected for taxonomic study. The three taxa each formed creamy white, rough colonies, had an optimal growth temperature of 30 °C, hydrolyzed Tween 80, were catalase-positive at 22 °C and expressed arylsulfatase activity. All three were susceptible to amikacin, ciprofloxacin and tigecycline. The three taxa produced specific sets of mycolic acids, including one family that has never previously been described, as determined by thin layer chromatography and nuclear magnetic resonance. The partial rpoB sequences (723 bp) showed 4-6 % divergence from each other and more than 5 % differences from the most similar species. Partial 16S rRNA gene sequences showed 99 % identity within each species. The most similar sequences for 16S rRNA genes (98-99 % identity over 1444-1461 bp) were found in the Mycobacterium fortuitum group, Mycobacterium septicum and Mycobacterium farcinogenes. The three taxa formed a new clade (bootstrap value, 99 %) on trees reconstructed from concatenated partial 16S rRNA, hsp65 and rpoB sequences. The above results led us to propose three novel species for the three groups of isolates, namely Mycobacterium lutetiense sp. nov. [type strain 071T=ParisRGMnew_1T (CIP 110656T=DSM 46713T)], Mycobacterium montmartrense sp. nov. [type strain 196T=ParisRGMnew_2T (CIP 110655T=DSM 46714T)] and Mycobacteriu marcueilense sp. nov. [type strain of 269T=ParisRGMnew_3T (CIP 110654T=DSM 46715T)].

Esters of pyrazinoic acid are active against pyrazinamide-resistant strains of Mycobacterium tuberculosis and other naturally resistant mycobacteria in vitro and ex vivo within macrophages.

KAUST Repository

Pires, David; Valente, Emí lia; Simoes, Marta; Carmo, Nuno; Testa, Bernard; Constantino, Luí s; Anes, Elsa

2015-01-01

In previous work, we have shown that POA esters and amides synthesized in our laboratory were stable in plasma. Although the amides did not present significant activity, the esters were active against sensitive mycobacteria at concentrations 5-to-10 fold lower than those of PZA. Here, we report that these POA derivatives possess antibacterial efficacy in vitro and ex vivo against several species and strains of Mycobacterium with natural or acquired resistance to PZA, including M. bovis and M. avium. Our results indicate that the resistance was probably overcome by cleavage of the prodrugs into POA and a long-chain alcohol. Although it is not possible to rule out that the esters may have intrinsic activity per se, we bring evidence here that long-chain fatty alcohols possess a significant anti-mycobacterial effect against PZA-resistant species and strains and are not mere inactive promoieties. These findings may lead to candidate dual-drugs having enhanced activity against both PZA-susceptible and PZA-resistant isolates and being suitable for clinical development.

Production and characterization of guinea pig recombinant gamma interferon and its effect on macrophage activation.

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Jeevan, A; McFarland, C T; Yoshimura, T; Skwor, T; Cho, H; Lasco, T; McMurray, D N

2006-01-01

Gamma interferon (IFN-gamma) plays a critical role in the protective immune responses against mycobacteria. We previously cloned a cDNA coding for guinea pig IFN-gamma (gpIFN-gamma) and reported that BCG vaccination induced a significant increase in the IFN-gamma mRNA expression in guinea pig cells in response to living mycobacteria and that the virulent H37Rv strain of Mycobacterium tuberculosis stimulated less IFN-gamma mRNA than did the attenuated H37Ra strain. In this study, we successfully expressed and characterized recombinant gpIFN-gamma with a histidine tag at the N terminus (His-tagged rgpIFN-gamma) in Escherichia coli. rgpIFN-gamma was identified as an 18-kDa band in the insoluble fraction; therefore, the protein was purified under denaturing conditions and renatured. N-terminal amino acid sequencing of the recombinant protein yielded the sequence corresponding to the N terminus of His-tagged gpIFN-gamma. The recombinant protein upregulated major histocompatibility complex class II expression in peritoneal macrophages. The antiviral activity of rgpIFN-gamma was demonstrated with a guinea pig fibroblast cell line (104C1) infected with encephalomyocarditis virus. Interestingly, peritoneal macrophages treated with rgpIFN-gamma did not produce any nitric oxide but did produce hydrogen peroxide and suppressed the intracellular growth of mycobacteria. Furthermore, rgpIFN-gamma induced morphological alterations in cultured macrophages. Thus, biologically active rgpIFN-gamma has been successfully produced and characterized in our laboratory. The study of rgpIFN-gamma will further increase our understanding of the cellular and molecular responses induced by BCG vaccination in the guinea pig model of pulmonary tuberculosis.

Original Mycobacterial Sin, a consequence of highly homologous antigens?

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Jenkins, A O; Michel, A; Rutten, V

2017-05-01

The role of antigens shared between Mycobacteria in in-vivo cross-reactive immune responses in host animals, have been reported to be responsible for reduced BCG vaccination efficacy as well reduced specificity of routine immunological diagnostic tests. This presents with significant disease control challenges in humans and animals. The present review highlights the results of previous studies on the effect of pre-sensitization to environmental mycobacteria on either pathogenic mycobacteria and/or M. bovis BCG, in experimental animals. It also takes an in-depth view into assessing the genetic similarities and relationships between atypical mycobacteria and Mycobacterium tuberculosis complex (MTBC) and how they might explain the immunological imprint of environmental mycobacteria in directing the hosts' immune response upon subsequent exposure to other classes of mycobacteria. The outcome of this review suggests that genetic closeness between particular atypical mycobacteria and MTBC usually indicate a higher level of homology for certain shared protective antigens. This ultimately results in a higher level of cross reactive immune responses as compared with other atypical mycobacteria that are further away genetically. This would explain the different effects of environmental mycobacteria on MTBC that have been reported in the different studies. In other words the direction of the host immune system in response to exposure to MTBC would depend on the type of environmental mycobacteria that was encountered in the initial exposure. We also explain these mycobacterial interactions in the context of the phenomenon of "Original Mycobacterial Sin". The effects of these inevitable mycobacterial interactions on field diagnosis and control by vaccination and how to circumvent them are discussed. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Prevalence and species spectrum of both pulmonary and extrapulmonary nontuberculous mycobacteria isolates at a tertiary care center

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Jyoti Umrao

2016-01-01

Full Text Available Objective/background: Nontuberculous mycobacteria (NTM infection associated with pulmonary and extrapulmonary disease has been increasing globally. Despite an increase in incidence rate of NTM infection, its prevalence, species diversity, and circulation pattern in India is largely unknown. This study sought to investigate the overall burden and diversity of NTM among both pulmonary and extrapulmonary clinical isolates from a Northern Indian population. Methods: The study was conducted in the Department of Microbiology, from January 2013 to December 2015. A total of 4620 clinical samples were collected from patients suspected to have pulmonary and extrapulmonary tuberculosis. Preliminary diagnosis was performed using Ziehl–Neelsen staining followed by liquid culture in BacT/ALERT three-dimensional system. A total of 906 positive cultures obtained were differentiated as either NTM or Mycobacterium tuberculosis complex using a biochemical and MPT64 antigen test. Further identification of NTM species was confirmed with a line probe assay. Results: Out of 906 cultures isolates, 263 (29.0% were confirmed as NTM and 643 (71.0% were identified as Mycobacterium tuberculosis complex. A total of 79.4% of the NTM were recovered from pulmonary and 18.2% from extrapulmonary specimens. The diversity of NTM species was high (13 species and predominated by Mycobacterium abscessus (31.3% followed by Mycobacterium fortuitum (22%, Mycobacterium intracellulare (13.6%, Mycobacterium chelonae (9.1%, however, M. abscessus and M. fortuitum were the predominant species in both types of clinical isolates. Men (60.4% and older patients aged greater than 55 years were the predominated risk group for NTM infection. Conclusion: The high prevalence and species diversity of NTM suggests the need for immediate and accurate characterization of NTM for proper treatment and management of patients.

Comparison of clinico-radiological features of patients with positive cultures of nontuberculous mycobacteria and patients with tuberculosis

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Ba-Hammam, Ahmed; Sharif, Yasir; Masood, Mohammad; Isnani, Arthur; Youssef, Ismael; Kambal, Abdelmageed; Shaikh, Shaffi

2005-01-01

To identify the clinico-radiological features of patients with positive cultures for nontuberculous mycobacteria (NTM) and compare those to a sample of patients with tuberculosis (MTB). A laboratory database was used to retrieve all specimens submitted to King Khalid University Hospital, Riyadh, mycobacteriology laboratory for mycobacterial smears and cultures during the period from October 1999-April 2002. Using this database, the original records of the mycobacteriology laboratory and a review of the patient's health records, a standard proforma was completed that included demographic, clinical, radiological and laboratory information on patients included in this study. The patients were divided into 2 groups; the NTM group, which included patients with positive cultures for NTM and the MTB group, which included a sample of patients with documented tuberculosis. During the study period, 286 patients had positive mycobacterial cultures. Seventy patients (24.5%) grew NTM and 216 (75.5%) grew MTB. For patients with MTB, 54 patients were included as per the selection protocol of the study. There was no difference between the 2 groups in all measured demographic variables. The presence of weight loss and fever was significantly more in the MTB group. Radiologically, the presence of hilar adenopathy was more significant among patients with MTB than those with NTM (17% versus 4%, p=0.02). However, bronchiectatic changes were seen significantly more among NTM patients compared to patients with MTB (26% versus 11%, p=0.03). The isolation of NTM in the mycobacteriology laboratory is high. The clinico-radiological features were not sufficiently specific to differentiate patients with NTM from patients with MTB. Local studies are needed to explore NTM disease in various developing countries and identify the NTM species causing infections in non-immunosuppressed patients in each locality. (author)

Evaluation of amplified rDNA restriction analysis (ARDRA for the identification of cultured mycobacteria in a diagnostic laboratory

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Rottiers Sylvianne

2002-03-01

Full Text Available Abstract Background The development of DNA amplification for the direct detection of M. tuberculosis from clinical samples has been a major goal of clinical microbiology during the last ten years. However, the limited sensitivity of most DNA amplification techniques restricts their use to smear positive samples. On the other hand, the development of automated liquid culture has increased the speed and sensitivity of cultivation of mycobacteria. We have opted to combine automated culture with rapid genotypic identification (ARDRA: amplified rDNA restriction analysis for the detection resp. identification of all mycobacterial species at once, instead of attempting direct PCR based detection from clinical samples of M. tuberculosis only. Results During 1998–2000 a total of approx. 3500 clinical samples was screened for the presence of M. tuberculosis. Of the 151 culture positive samples, 61 were M. tuberculosis culture positive. Of the 30 smear positive samples, 26 were M. tuberculosis positive. All but three of these 151 mycobacterial isolates could be identified with ARDRA within on average 36 hours. The three isolates that could not be identified belonged to rare species not yet included in our ARDRA fingerprint library or were isolates with an aberrant pattern. Conclusions In our hands, automated culture in combination with ARDRA provides with accurate, practically applicable, wide range identification of mycobacterial species. The existing identification library covers most species, and can be easily updated when new species are studied or described. The drawback is that ARDRA is culture-dependent, since automated culture of M. tuberculosis takes on average 16.7 days (range 6 to 29 days. However, culture is needed after all to assess the antibiotic susceptibility of the strains.

Revisiting the structure of the anti-neoplastic glucans of Mycobacterium bovis Bacille Calmette-Guerin. Structural analysis of the extracellular and boiling water extract-derived glucans of the vaccine substrains.

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Dinadayala, Premkumar; Lemassu, Anne; Granovski, Pierre; Cérantola, Stéphane; Winter, Nathalie; Daffé, Mamadou

2004-03-26

The attenuated strain of Mycobacterium bovis Bacille Calmette-Guérin (BCG), used worldwide to prevent tuberculosis and leprosy, is also clinically used as an immunotherapeutic agent against superficial bladder cancer. An anti-tumor polysaccharide has been isolated from the boiling water extract of the Tice substrain of BCG and tentatively characterized as consisting primarily of repeating units of 6-linked-glucosyl residues. Mycobacterium tuberculosis and other mycobacterial species produce a glycogen-like alpha-glucan composed of repeating units of 4-linked glucosyl residues substituted at some 6 positions by short oligoglucosyl units that also exhibits an anti-tumor activity. Therefore, the impression prevails that mycobacteria synthesize different types of anti-neoplastic glucans or, alternatively, the BCG substrains are singular in producing a unique type of glucan that may confer to them their immunotherapeutic property. The present study addresses this question through the comparative analysis of alpha-glucans purified from the extracellular materials and boiling water extracts of three vaccine substrains. The polysaccharides were purified, and their structural features were established by mono- and two-dimensional NMR spectroscopy and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry of the enzymatic and chemical degradation products of the purified compounds. The glucans isolated by the two methods from the three substrains of BCG were shown to exhibit identical structural features shared with the glycogen-like alpha-glucan of M. tuberculosis and other mycobacteria. Incidentally, we observed an occasional release of dextrans from Sephadex columns that may explain the reported occurrence of 6-substituted alpha-glucans in mycobacteria.

Mycobacterium-Host Cell Relationships in Granulomatous Lesions in a Mouse Model of Latent Tuberculous Infection

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Elena Ufimtseva

2015-01-01

Full Text Available Tuberculosis (TB is a dangerous infectious disease characterized by a tight interplay between mycobacteria and host cells in granulomatous lesions (granulomas during the latent, asymptomatic stage of infection. Mycobacterium-host cell relationships were analyzed in granulomas obtained from various organs of BALB/c mice with chronic TB infection caused by in vivo exposure to the Bacillus Calmette-Guérin (BCG vaccine. Acid-fast BCG-mycobacteria were found to be morphologically and functionally heterogeneous (in size, shape, and replication rates in colonies in granuloma macrophages, dendritic cells, and multinucleate Langhans giant cells. Cord formation by BCG-mycobacteria in granuloma cells has been observed. Granuloma macrophages retained their ability to ingest damaged lymphocytes and thrombocytes in the phagosomes; however, their ability to destroy BCG-mycobacteria contained in these cells was compromised. No colocalization of BCG-mycobacteria and the LysoTracker dye was observed in the mouse cells. Various relationships between granuloma cells and BCG-mycobacteria were observed in different mice belonging to the same line. Several mice totally eliminated mycobacterial infection. Granulomas in the other mice had mycobacteria actively replicating in cells of different types and forming cords, which is an indicator of mycobacterial virulence and, probably, a marker of the activation of tuberculous infection in animals.

Mycobacterium-Host Cell Relationships in Granulomatous Lesions in a Mouse Model of Latent Tuberculous Infection

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2015-01-01

Tuberculosis (TB) is a dangerous infectious disease characterized by a tight interplay between mycobacteria and host cells in granulomatous lesions (granulomas) during the latent, asymptomatic stage of infection. Mycobacterium-host cell relationships were analyzed in granulomas obtained from various organs of BALB/c mice with chronic TB infection caused by in vivo exposure to the Bacillus Calmette-Guérin (BCG) vaccine. Acid-fast BCG-mycobacteria were found to be morphologically and functionally heterogeneous (in size, shape, and replication rates in colonies) in granuloma macrophages, dendritic cells, and multinucleate Langhans giant cells. Cord formation by BCG-mycobacteria in granuloma cells has been observed. Granuloma macrophages retained their ability to ingest damaged lymphocytes and thrombocytes in the phagosomes; however, their ability to destroy BCG-mycobacteria contained in these cells was compromised. No colocalization of BCG-mycobacteria and the LysoTracker dye was observed in the mouse cells. Various relationships between granuloma cells and BCG-mycobacteria were observed in different mice belonging to the same line. Several mice totally eliminated mycobacterial infection. Granulomas in the other mice had mycobacteria actively replicating in cells of different types and forming cords, which is an indicator of mycobacterial virulence and, probably, a marker of the activation of tuberculous infection in animals. PMID:26064970

M. tuberculosis induces potent activation of IDO-1, but this is not essential for the immunological control of infection.

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Antje Blumenthal

Full Text Available Indoleamine 2,3-dioxygenesae-1 (IDO-1 catalyses the initial, rate-limiting step in tryptophan metabolism, thereby regulating tryptophan availability and the formation of downstream metabolites, including picolinic and quinolinic acid. We found that Mycobacterium tuberculosis infection induced marked upregulation of IDO-1 expression in both human and murine macrophages in vitro and in the lungs of mice following aerosol challenge with M. tuberculosis. The absence of IDO-1 in dendritic cells enhanced the activation of mycobacteria-specific T cells in vitro. Interestingly, IDO-1-deficiency during M. tuberculosis infection in mice was not associated with altered mycobacteria-specific T cell responses in vivo. The bacterial burden of infected organs, pulmonary inflammatory responses, and survival were also comparable in M. tuberculosis-infected IDO-1 deficient and wild type animals. Tryptophan is metabolised into either picolinic acid or quinolinic acid, but only picolinic acid inhibited the growth of M. tuberculosis in vitro. By contrast macrophages infected with pathogenic mycobacteria, produced quinolinic, rather than picolinic acid, which did not reduce M. tuberculosis growth in vitro. Therefore, although M. tuberculosis induces robust expression of IDO-1 and activation of tryptophan metabolism, IDO-1-deficiency fails to impact on the immune control and the outcome of the infection in the mouse model of tuberculosis.

Cd1b-Mediated T Cell Recognition of a Glycolipid Antigen Generated from Mycobacterial Lipid and Host Carbohydrate during Infection

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Moody, D. Branch; Guy, Mark R.; Grant, Ethan; Cheng, Tan-Yun; Brenner, Michael B.; Besra, Gurdyal S.; Porcelli, Steven A.

2000-01-01

T cells recognize microbial glycolipids presented by CD1 proteins, but there is no information regarding the generation of natural glycolipid antigens within infected tissues. Therefore, we determined the molecular basis of CD1b-restricted T cell recognition of mycobacterial glycosylated mycolates, including those produced during tissue infection in vivo. Transfection of the T cell receptor (TCR) α and β chains from a glucose monomycolate (GMM)-specific T cell line reconstituted GMM recognition in TCR-deficient T lymphoblastoma cells. This TCR-mediated response was highly specific for natural mycobacterial glucose-6-O-(2R, 3R) monomycolate, including the precise structure of the glucose moiety, the stereochemistry of the mycolate lipid, and the linkage between the carbohydrate and the lipid. Mycobacterial production of antigenic GMM absolutely required a nonmycobacterial source of glucose that could be supplied by adding glucose to media at concentrations found in mammalian tissues or by infecting tissue in vivo. These results indicate that mycobacteria synthesized antigenic GMM by coupling mycobacterial mycolates to host-derived glucose. Specific T cell recognition of an epitope formed by interaction of host and pathogen biosynthetic pathways provides a mechanism for immune response to those pathogenic mycobacteria that have productively infected tissues, as distinguished from ubiquitous, but innocuous, environmental mycobacteria. PMID:11015438

The level of PPD-specific IFN-gamma-producing CD4+ T cells in the blood predicts the in vivo response to PPD.

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Martins, Marcia Valéria B S; Lima, Mônica Cristina B S; Duppre, Nadia C; Matos, Haroldo J; Spencer, John S; Brennan, Patrick J; Sarno, Euzenir N; Fonseca, Leila; Pereira, Geraldo M B; Pessolani, Maria Cristina V

2007-05-01

There are no reliable means for detecting subclinical mycobacterial infections. The recent sequencing of several mycobacterial genomes has now afforded new opportunities for the development of pathogen-specific diagnostic tests, critical in the context of leprosy and tuberculosis control. In the present study, we applied a multi-parametric flow cytometric analysis that allowed the investigation of T-cell functions in order to define immunological markers that measure previous exposure to mycobacteria. We compared the in vivo response to PPD, the gold standard skin test reagent for measuring previous exposure to Mycobacterium tuberculosis, with in vitro parameters of leukocyte activation in five PPD positive and five PPD negative healthy volunteers. PPD-stimulated peripheral leukocytes expressing CD4, CD69, cutaneous lymphocyte-associated antigen (CLA) and intracellular IFN-gamma were enumerated in whole blood and compared with the size of in vivo PPD-induced induration and IFN-gamma production levels as measured by ELISA in supernatants of PPD-stimulated peripheral blood mononuclear cells. The reactivity to the tuberculin skin test (TST) was associated with markedly increased frequencies of PPD-responsive activated (CD69+) and IFN-gamma-producing CD4+T cells. Detection of PPD-specific IFN-gamma producing leukocytes was restricted to CD4+T cells and a subset of these cells was shown to express the skin homing molecule CLA. Multiple linear regression modeling of responses to PPD showed the highest association between skin test indurations and frequencies of PPD-responsive IFN-gamma-producing CD4+CD69+ T cells. Our data show that the in vitro enumeration of antigen-specific IFN-gamma-producing CD4+ T cells can provide an alternative to the in vivo tuberculin test for the detection of latent Mycobacterium tuberculosis infection. Moreover, the measurement of these immunological parameters can be useful for the screening of new specific antigens defined by the genome

Direct molecular mass determination of trehalose monomycolate from 11 species of mycobacteria by MALDI-TOF mass spectrometry.

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Fujita, Yukiko; Naka, Takashi; Doi, Takeshi; Yano, Ikuya

2005-05-01

Direct estimation of the molecular mass of single molecular species of trehalose 6-monomycolate (TMM), a ubiquitous cell-wall component of mycobacteria, was performed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. When less than 1 microg TMM was analysed by MALDI-TOF mass spectrometry, quasimolecular ions [M+Na]+ of each molecular species were demonstrated and the numbers of carbons and double bonds (or cyclopropane rings) were determined. Since the introduction of oxygen atoms such as carbonyl, methoxy and ester groups yielded the appropriate shift of mass ions, the major subclasses of mycolic acid (alpha, methoxy, keto and wax ester) were identified without resorting to hydrolytic procedures. The results showed a marked difference in the molecular species composition of TMM among mycobacterial species. Unexpectedly, differing from other mycoloyl glycolipids, TMM from Mycobacterium tuberculosis showed a distinctive mass pattern, with abundant odd-carbon-numbered monocyclopropanoic (or monoenoic) alpha-mycolates besides dicyclopropanoic mycolate, ranging from C75 to C85, odd- and even-carbon-numbered methoxymycolates ranging from C83 to C94 and even- and odd-carbon-numbered ketomycolates ranging from C83 to C90. In contrast, TMM from Mycobacterium bovis (wild strain and BCG substrains) possessed even-carbon-numbered dicyclopropanoic alpha-mycolates. BCG Connaught strain lacked methoxymycolates almost completely. These results were confirmed by MALDI-TOF mass analysis of mycolic acid methyl esters liberated by alkaline hydrolysis and methylation of the original TMM. Wax ester-mycoloyl TMM molecular species were demonstrated for the first time as an intact form in the Mycobacterium avium-intracellulare group, M. phlei and M. flavescens. The M. avium-intracellulare group possessed predominantly C85 and C87 wax ester-mycoloyl TMM, while M. phlei and the rapid growers tested contained C80, C81, C82 and C83 wax ester

Health Impacts of Environmental Mycobacteria†

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Primm, Todd P.; Lucero, Christie A.; Falkinham, Joseph O.

2004-01-01

Environmental mycobacteria are emerging pathogens causing opportunistic infections in humans and animals. The health impacts of human-mycobacterial interactions are complex and likely much broader than currently recognized. Environmental mycobacteria preferentially survive chlorination in municipal water, using it as a vector to infect humans. Widespread chlorination of water has likely selected more resistant environmental mycobacteria species and potentially explains the shift from M. scrof...

'Streptomyces caelicus', an antibiotic-producing species of the genus Streptomyces, and Streptomyces canchipurensis Li et al. 2015 are later heterotypic synonyms of Streptomyces muensis Ningthoujam et al. 2014.

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Wink, Joachim; Schumann, Peter; Atasayar, Ewelina; Klenk, Hans-Peter; Zaburannyi, Nestor; Westermann, Martin; Martin, Karin; Glaeser, Stefanie P; Kämpfer, Peter

2017-04-01

'Streptomyces caelicus' DSM 40835 was first reported as the producer of the antibiotic griselimycin by some coworkers of Rhone Poulenc in 1971. The project on isolation of the antibiotic compound was stopped because of the bad solubility and selectivity of the compound towards Mycobacteria. At Sanofi-Aventis, Germany, the project was re-evaluated in 2007 and the gene cluster of griselimycin could be identified, characterized and was patented in 2013. At this time, 'S. caelicus' was an invalid name. During the strain characterization work, it was found that 'S. caelicus' belongs to the group of species of the genus Streptomyces which show an unusual heterogeneity of the 16S rRNA gene sequences. However, high 16S rRNA gene sequence similarities to Streptomyces muensis JCM 17576T and Streptomyces canchipurensis JCM 17575T were obvious. Here, we present a comparative description of 'Streptomyces caelicus' DS 9461 (=DSM 40835=NCCB 100592) with S. muensis and S. canchipurensis by use of a polyphasic taxonomy approach and additional comparison of some housekeeping genes by multilocus sequence analysis (MLSA). An emended description of Streptomyces muensis is provided as a result of this work.

Natural killer cell cytokine response to M. bovis BCG Is associated with inhibited proliferation, increased apoptosis and ultimate depletion of NKp44(+CD56(bright cells.

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Damien Portevin

Full Text Available Mycobacterium bovis BCG, a live attenuated strain of M. bovis initially developed as a vaccine against tuberculosis, is also used as an adjuvant for immunotherapy of cancers and for treatment of parasitic infections. The underlying mechanisms are thought to rely on its immunomodulatory properties including the recruitment of natural killer (NK cells. In that context, we aimed to study the impact of M. bovis BCG on NK cell functions. We looked at cytotoxicity, cytokine production, proliferation and cell survival of purified human NK cells following exposure to single live particles of mycobacteria. We found that M. bovis BCG mediates apoptosis of NK cells only in the context of IL-2 stimulation during which CD56(bright NK cells are releasing IFN-γ in response to mycobacteria. We found that the presence of mycobacteria prevented the IL-2 induced proliferation and surface expression of NKp44 receptor by the CD56(bright population. In summary, we observed that M. bovis BCG is modulating the functions of CD56(bright NK cells to drive this subset to produce IFN-γ before subsequent programmed cell death. Therefore, IFN-γ production by CD56(bright cells constitutes the main effector mechanism of NK cells that would contribute to the benefits observed for M. bovis BCG as an immunotherapeutic agent.

Catalytic function of the mycobacterial binuclear iron monooxygenase in acetone metabolism.

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Furuya, Toshiki; Nakao, Tomomi; Kino, Kuniki

2015-10-01

Mycobacteria such as Mycobacterium smegmatis strain mc(2)155 and Mycobacterium goodii strain 12523 are able to grow on acetone and use it as a source of carbon and energy. We previously demonstrated by gene deletion analysis that the mimABCD gene cluster, which encodes a binuclear iron monooxygenase, plays an essential role in acetone metabolism in these mycobacteria. In the present study, we determined the catalytic function of MimABCD in acetone metabolism. Whole-cell assays were performed using Escherichia coli cells expressing the MimABCD complex. When the recombinant E. coli cells were incubated with acetone, a product was detected by gas chromatography (GC) analysis. Based on the retention time and the gas chromatography-mass spectrometry (GC-MS) spectrum, the reaction product was identified as acetol (hydroxyacetone). The recombinant E. coli cells produced 1.02 mM of acetol from acetone within 24 h. Furthermore, we demonstrated that MimABCD also was able to convert methylethylketone (2-butanone) to 1-hydroxy-2-butanone. Although it has long been known that microorganisms such as mycobacteria metabolize acetone via acetol, this study provides the first biochemical evidence for the existence of a microbial enzyme that catalyses the conversion of acetone to acetol. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Buruli ulcer: wound care and rehabilitation

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Frimpong M

2016-06-01

Full Text Available Michael Frimpong,1 Fred Stephen Sarfo,2 Mabel Sarpong Duah,1 Mark Wansbrough-Jones,3 Richard O Phillips2 1Kumasi Centre for Collaborative Research in Tropical Medicine, 2Department of Medicine, School of Medical Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana; 3Institute for Infection and Immunity, St George’s University of London, London, UK Abstract: Buruli ulcer caused by Mycobacterium ulcerans is a neglected tropical disease characterized by extensive ulceration involving predominantly the upper and lower limbs of patients. The disease is common in rural tropical communities in West and Central Africa, where access to proper health care is limited. Pathogenesis of the characteristic painless ulcers is linked to the elaboration by M. ulcerans of a lipid toxin called mycolactone that has potent cytopathic, immunosuppressive, and analgesic effects on a host of cells in cutaneous tissues. Mycolactone is known to profoundly inhibit secretion of a plethora of proteins that are essential for wound healing. Even though a combination antibacterial therapy of streptomycin and rifampicin for 8 weeks is effective for treatment, it relies on good and appropriate wound management to prevent secondary bacterial infections and improve healing. Evidence-based interventions for wound care in Buruli ulcer disease are often lacking and have relied on expert advice and recommendations. Surgical interventions are limited to debridement of necrotic tissue and grafting of extensive ulcers, usually after antibiotic therapy. Patients’ rehabilitation is an important component of care to reduce disabilities associated with the disease and proper integration into the community after treatment. Keywords: Buruli ulcer, Mycobacterium ulcerans disease, Mycobacterium ulcerans, wound care, rehabilitation, disability

Diversity, community composition, and dynamics of nonpigmented and late-pigmenting rapidly growing mycobacteria in an urban tap water production and distribution system.

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Dubrou, S; Konjek, J; Macheras, E; Welté, B; Guidicelli, L; Chignon, E; Joyeux, M; Gaillard, J L; Heym, B; Tully, T; Sapriel, G

2013-09-01

Nonpigmented and late-pigmenting rapidly growing mycobacteria (RGM) have been reported to commonly colonize water production and distribution systems. However, there is little information about the nature and distribution of RGM species within the different parts of such complex networks or about their clustering into specific RGM species communities. We conducted a large-scale survey between 2007 and 2009 in the Parisian urban tap water production and distribution system. We analyzed 1,418 water samples from 36 sites, covering all production units, water storage tanks, and distribution units; RGM isolates were identified by using rpoB gene sequencing. We detected 18 RGM species and putative new species, with most isolates being Mycobacterium chelonae and Mycobacterium llatzerense. Using hierarchical clustering and principal-component analysis, we found that RGM were organized into various communities correlating with water origin (groundwater or surface water) and location within the distribution network. Water treatment plants were more specifically associated with species of the Mycobacterium septicum group. On average, M. chelonae dominated network sites fed by surface water, and M. llatzerense dominated those fed by groundwater. Overall, the M. chelonae prevalence index increased along the distribution network and was associated with a correlative decrease in the prevalence index of M. llatzerense, suggesting competitive or niche exclusion between these two dominant species. Our data describe the great diversity and complexity of RGM species living in the interconnected environments that constitute the water production and distribution system of a large city and highlight the prevalence index of the potentially pathogenic species M. chelonae in the distribution network.

Identification of the Regulator Gene Responsible for the Acetone-Responsive Expression of the Binuclear Iron Monooxygenase Gene Cluster in Mycobacteria ▿

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Furuya, Toshiki; Hirose, Satomi; Semba, Hisashi; Kino, Kuniki

2011-01-01

The mimABCD gene cluster encodes the binuclear iron monooxygenase that oxidizes propane and phenol in Mycobacterium smegmatis strain MC2 155 and Mycobacterium goodii strain 12523. Interestingly, expression of the mimABCD gene cluster is induced by acetone. In this study, we investigated the regulator gene responsible for this acetone-responsive expression. In the genome sequence of M. smegmatis strain MC2 155, the mimABCD gene cluster is preceded by a gene designated mimR, which is divergently transcribed. Sequence analysis revealed that MimR exhibits amino acid similarity with the NtrC family of transcriptional activators, including AcxR and AcoR, which are involved in acetone and acetoin metabolism, respectively. Unexpectedly, many homologs of the mimR gene were also found in the sequenced genomes of actinomycetes. A plasmid carrying a transcriptional fusion of the intergenic region between the mimR and mimA genes with a promoterless green fluorescent protein (GFP) gene was constructed and introduced into M. smegmatis strain MC2 155. Using a GFP reporter system, we confirmed by deletion and complementation analyses that the mimR gene product is the positive regulator of the mimABCD gene cluster expression that is responsive to acetone. M. goodii strain 12523 also utilized the same regulatory system as M. smegmatis strain MC2 155. Although transcriptional activators of the NtrC family generally control transcription using the σ54 factor, a gene encoding the σ54 factor was absent from the genome sequence of M. smegmatis strain MC2 155. These results suggest the presence of a novel regulatory system in actinomycetes, including mycobacteria. PMID:21856847

Direct and inverted repeats elicit genetic instability by both exploiting and eluding DNA double-strand break repair systems in mycobacteria.

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Ewelina A Wojcik

Full Text Available Repetitive DNA sequences with the potential to form alternative DNA conformations, such as slipped structures and cruciforms, can induce genetic instability by promoting replication errors and by serving as a substrate for DNA repair proteins, which may lead to DNA double-strand breaks (DSBs. However, the contribution of each of the DSB repair pathways, homologous recombination (HR, non-homologous end-joining (NHEJ and single-strand annealing (SSA, to this sort of genetic instability is not fully understood. Herein, we assessed the genome-wide distribution of repetitive DNA sequences in the Mycobacterium smegmatis, Mycobacterium tuberculosis and Escherichia coli genomes, and determined the types and frequencies of genetic instability induced by direct and inverted repeats, both in the presence and in the absence of HR, NHEJ, and SSA. All three genomes are strongly enriched in direct repeats and modestly enriched in inverted repeats. When using chromosomally integrated constructs in M. smegmatis, direct repeats induced the perfect deletion of their intervening sequences ~1,000-fold above background. Absence of HR further enhanced these perfect deletions, whereas absence of NHEJ or SSA had no influence, suggesting compromised replication fidelity. In contrast, inverted repeats induced perfect deletions only in the absence of SSA. Both direct and inverted repeats stimulated excision of the constructs from the attB integration sites independently of HR, NHEJ, or SSA. With episomal constructs, direct and inverted repeats triggered DNA instability by activating nucleolytic activity, and absence of the DSB repair pathways (in the order NHEJ>HR>SSA exacerbated this instability. Thus, direct and inverted repeats may elicit genetic instability in mycobacteria by 1 directly interfering with replication fidelity, 2 stimulating the three main DSB repair pathways, and 3 enticing L5 site-specific recombination.

Direct and inverted repeats elicit genetic instability by both exploiting and eluding DNA double-strand break repair systems in mycobacteria.

Science.gov (United States)

Wojcik, Ewelina A; Brzostek, Anna; Bacolla, Albino; Mackiewicz, Pawel; Vasquez, Karen M; Korycka-Machala, Malgorzata; Jaworski, Adam; Dziadek, Jaroslaw

2012-01-01

Repetitive DNA sequences with the potential to form alternative DNA conformations, such as slipped structures and cruciforms, can induce genetic instability by promoting replication errors and by serving as a substrate for DNA repair proteins, which may lead to DNA double-strand breaks (DSBs). However, the contribution of each of the DSB repair pathways, homologous recombination (HR), non-homologous end-joining (NHEJ) and single-strand annealing (SSA), to this sort of genetic instability is not fully understood. Herein, we assessed the genome-wide distribution of repetitive DNA sequences in the Mycobacterium smegmatis, Mycobacterium tuberculosis and Escherichia coli genomes, and determined the types and frequencies of genetic instability induced by direct and inverted repeats, both in the presence and in the absence of HR, NHEJ, and SSA. All three genomes are strongly enriched in direct repeats and modestly enriched in inverted repeats. When using chromosomally integrated constructs in M. smegmatis, direct repeats induced the perfect deletion of their intervening sequences ~1,000-fold above background. Absence of HR further enhanced these perfect deletions, whereas absence of NHEJ or SSA had no influence, suggesting compromised replication fidelity. In contrast, inverted repeats induced perfect deletions only in the absence of SSA. Both direct and inverted repeats stimulated excision of the constructs from the attB integration sites independently of HR, NHEJ, or SSA. With episomal constructs, direct and inverted repeats triggered DNA instability by activating nucleolytic activity, and absence of the DSB repair pathways (in the order NHEJ>HR>SSA) exacerbated this instability. Thus, direct and inverted repeats may elicit genetic instability in mycobacteria by 1) directly interfering with replication fidelity, 2) stimulating the three main DSB repair pathways, and 3) enticing L5 site-specific recombination.

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

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Boehringer, Daniel; Ban, Nenad; Leibundgut, Marc

2013-03-11

The mycobacterial fatty acid synthase (FAS) complex is a giant 2.0-MDa α(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. Copyright © 2012 Elsevier Ltd. All rights reserved.

A broad set of different llama antibodies specific for a 16 kDa heat shock protein of Mycobacterium tuberculosis.

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Anke K Trilling

Full Text Available BACKGROUND: Recombinant antibodies are powerful tools in engineering of novel diagnostics. Due to the small size and stable nature of llama antibody domains selected antibodies can serve as a detection reagent in multiplexed and sensitive assays for M. tuberculosis. METHODOLOGY/PRINCIPAL FINDINGS: Antibodies for Mycobacterium tuberculosis (M. tb recognition were raised in Alpaca, and, by phage display, recombinant variable domains of heavy-chain antibodies (VHH binding to M. tuberculosis antigens were isolated. Two phage display selection strategies were followed: one direct selection using semi-purified protein antigen, and a depletion strategy with lysates, aiming to avoid cross-reaction to other mycobacteria. Both panning methods selected a set of binders with widely differing complementarity determining regions. Selected recombinant VHHs were produced in E. coli and shown to bind immobilized lysate in direct Enzymelinked Immunosorbent Assay (ELISA tests and soluble antigen by surface plasmon resonance (SPR analysis. All tested VHHs were specific for tuberculosis-causing mycobacteria (M. tuberculosis, M. bovis and exclusively recognized an immunodominant 16 kDa heat shock protein (hsp. The highest affinity VHH had a dissociation constant (KD of 4 × 10(-10 M. CONCLUSIONS/SIGNIFICANCE: A broad set of different llama antibodies specific for 16 kDa heat shock protein of M. tuberculosis is available. This protein is highly stable and abundant in M. tuberculosis. The VHH that detect this protein are applied in a robust SPR sensor for identification of tuberculosis-causing mycobacteria.

Genomic Analysis of Pathogenicity Determinants in Mycobacterium kansasii Type I

KAUST Repository

Guan, Qingtian

2016-01-01

Mycobacteria, a genus within Actinobacteria Phylum, are well known for two pathogens that cause human diseases: leprosy and tuberculosis. Other than the obligate human mycobacteria, there is a group of bacteria that are present in the environment

Comparison of methods for mycobacteria isolation from swine feces Comparação de métodos para isolamento de micobactérias a partir de fezes suínas

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Eugenia Márcia de Deus Oliveira

2007-12-01

Full Text Available Swine mycobacteriosis is an important cause of carcass condemnation at abattoirs. One of the best ways to recognize the etiologic agent involved, in live animals, is the fecal isolation, as 94% of the lesions are located in the digestive tract. Therefore, the goal of the present study was to compare the performance of four decontamination methods followed by inoculation in three different culture media, totalizing twelve procedures of mycobacteria search from swine fecal samples experimentally contaminated. The swine feces were artificially contaminated with 0.02 g of Mycobacterium avium, PIG-B strain, and subjected to mycobacteria isolation trial. The protocols used were: 1 modified Petroff or basic method; 2 modified Lowenstein-Jensen or acidic method; 3 modified Petroff or basic method with re-suspension in Amphotericin B; 4 modified Lowenstein-Jensen or acid method with re-suspension in Amphotericin B, followed by inoculation in Petragnani, Lowenstein-Jensen and Lowenstein-Jensen medium with antibiotics (Penicillin G and Nalidixic acid. There was a difference (pAs micobacterioses suínas são responsáveis por condenações de carcaças em abatedouro e uma das melhores formas de se conhecer os agentes envolvidos nos animais vivos é o isolamento a partir das fezes, pois em 94% das vezes, as lesões localizam-se no trato digestivo. Assim sendo, o presente estudo teve por objetivo comparar o desempenho de quatro métodos de descontaminação com semeadura em três diferentes meios de cultura, totalizando doze procedimentos na pesquisa de micobactérias a partir de amostras de fezes de suínos contaminadas experimentalmente. Amostras de fezes de suínos foram contaminadas artificialmente com 0,02g de Mycobacterium avium, estirpe de PIG-B, e submetidas à tentativa de isolamento de micobactérias, utilizando-se os seguintes protocolos de descontaminação: 1 Petroff modificado ou método básico; 2 Lowenstein-Jensen modificado ou método �

Utility of gastric aspirates for diagnosing tuberculosis in children in a low prevalence area: predictors of positive cultures and significance of non-tuberculous mycobacteria.

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Kordy, Faisal; Richardson, Susan E; Stephens, Derek; Lam, Ray; Jamieson, Frances; Kitai, Ian

2015-01-01

In countries with low rates of tuberculosis (TB), yields of gastric aspirates (GAs) for Mycobacterium tuberculosis (MTB) culture are low. The significance of non-tuberculous mycobacteria (NTM) isolated from GA is uncertain. We reviewed clinical, microbiologic and radiologic data for children who underwent GA between 1999 and 2011 at Sick Kids, Toronto. Radiologic features of cases were compared with those of age matched controls. 785 GAs were obtained from 285 patients of whom 20 (7%) had positive MTB cultures: in 15 patients the GA was the only positive culture for MTB. Of 15 culture-positive patients who underwent exactly 3 GAs, MTB was isolated from the first lavage in 10 (67%), only from the second in 3 (20%) and only from the third in 2 (13%). On univariate analysis, miliary disease and intrathoracic lymphadenopathy were associated with a positive GA MTB culture. On multiple conditional logistic regression analysis, adenopathy remained significant (OR 10.2 [95% CI 2.0-51.4] p =0.005). Twelve patients had NTM isolated, most commonly M. avium complex: none had evidence of invasive NTM disease during a median duration of 12 months of follow-up. Causal pathogens different from the GA NTM culture were isolated from biopsies or bronchoalveolar lavage in 3. GAs continue to be important for TB diagnosis in children. Three GAs have a yield better than 1. Those with miliary or disseminated TB and intrathoracic lymphadenopathy have highest yields. NTM isolates from GA are likely unimportant and can be clinically misleading.

Influence of ESAT-6 secretion system 1 (RD1) of Mycobacterium tuberculosis on the interaction between mycobacteria and the host immune system.

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Majlessi, Laleh; Brodin, Priscille; Brosch, Roland; Rojas, Marie-Jésus; Khun, Huot; Huerre, Michel; Cole, Stewart T; Leclerc, Claude

2005-03-15

The chromosomal locus encoding the early secreted antigenic target, 6 kDa (ESAT-6) secretion system 1 of Mycobacterium tuberculosis, also referred to as "region of difference 1 (RD1)," is absent from Mycobacterium bovis bacillus Calmette-Guerin (BCG). In this study, using low-dose aerosol infection in mice, we demonstrate that BCG complemented with RD1 (BCG::RD1) displays markedly increased virulence which albeit does not attain that of M. tuberculosis H37Rv. Nevertheless, phenotypic and functional analyses of immune cells at the site of infection show that the capacity of BCG::RD1 to initiate recruitment/activation of immune cells is comparable to that of fully virulent H37Rv. Indeed, in contrast to the parental BCG, BCG::RD1 mimics H37Rv and induces substantial influx of activated (CD44highCD45RB(-)CD62L(-)) or effector (CD45RB(-)CD27(-)) T cells and of activated CD11c(+)CD11bhigh cells to the lungs of aerosol-infected mice. For the first time, using in vivo analysis of transcriptome of inflammatory cytokines and chemokines of lung interstitial CD11c+ cells, we show that in a low-dose aerosol infection model, BCG::RD1 triggered an activation/inflammation program comparable to that induced by H37Rv while parental BCG, due to its overattenuation, did not initiate the activation program in lung interstitial CD11c+ cells. Thus, products encoded by the ESAT-6 secretion system 1 of M. tuberculosis profoundly modify the interaction between mycobacteria and the host innate and adaptive immune system. These modifications can explain the previously described improved protective capacity of BCG::RD1 vaccine candidate against M. tuberculosis challenge.

Growth characteristics of liquid cultures increase the reliability of presumptive identification of Mycobacterium tuberculosis complex.

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Pinhata, Juliana Maira Watanabe; Felippe, Isis Moreira; Gallo, Juliana Failde; Chimara, Erica; Ferrazoli, Lucilaine; de Oliveira, Rosangela Siqueira

2018-04-23

We evaluated the microscopic and macroscopic characteristics of mycobacteria growth indicator tube (MGIT) cultures for the presumptive identification of the Mycobacterium tuberculosis complex (MTBC) and assessed the reliability of this strategy for correctly directing isolates to drug susceptibility testing (DST) or species identification. A total of 1526 isolates of mycobacteria received at the Instituto Adolfo Lutz were prospectively subjected to presumptive identification by the observation of growth characteristics along with cord formation detection via microscopy. The presumptive identification showed a sensitivity, specificity and accuracy of 98.8, 92.5 and 97.9 %, respectively. Macroscopic analysis of MTBC isolates that would have been erroneously classified as non-tuberculous mycobacteria based solely on microscopic morphology enabled us to direct them rapidly to DST, representing a substantial gain to patients. In conclusion, the growth characteristics of mycobacteria in MGIT, when considered along with cord formation, increased the reliability of the presumptive identification, which has a great impact on the laboratory budget and turnaround times.

US Cystic Fibrosis Foundation and European Cystic Fibrosis Society consensus recommendations for the management of non-tuberculous mycobacteria in individuals with cystic fibrosis.

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Floto, R Andres; Olivier, Kenneth N; Saiman, Lisa; Daley, Charles L; Herrmann, Jean-Louis; Nick, Jerry A; Noone, Peadar G; Bilton, Diana; Corris, Paul; Gibson, Ronald L; Hempstead, Sarah E; Koetz, Karsten; Sabadosa, Kathryn A; Sermet-Gaudelus, Isabelle; Smyth, Alan R; van Ingen, Jakko; Wallace, Richard J; Winthrop, Kevin L; Marshall, Bruce C; Haworth, Charles S

2016-01-01

Non-tuberculous mycobacteria (NTM) are ubiquitous environmental organisms that can cause chronic pulmonary infection, particularly in individuals with pre-existing inflammatory lung disease such as cystic fibrosis (CF). Pulmonary disease caused by NTM has emerged as a major threat to the health of individuals with CF but remains difficult to diagnose and problematic to treat. In response to this challenge, the US Cystic Fibrosis Foundation (CFF) and the European Cystic Fibrosis Society (ECFS) convened an expert panel of specialists to develop consensus recommendations for the screening, investigation, diagnosis and management of NTM pulmonary disease in individuals with CF. Nineteen experts were invited to participate in the recommendation development process. Population, Intervention, Comparison, Outcome (PICO) methodology and systematic literature reviews were employed to inform draft recommendations. An anonymous voting process was used by the committee to reach consensus. All committee members were asked to rate each statement on a scale of: 0, completely disagree, to 9, completely agree; with 80% or more of scores between 7 and 9 being considered 'good' agreement. Additionally, the committee solicited feedback from the CF communities in the USA and Europe and considered the feedback in the development of the final recommendation statements. Three rounds of voting were conducted to achieve 80% consensus for each recommendation statement. Through this process, we have generated a series of pragmatic, evidence-based recommendations for the screening, investigation, diagnosis and treatment of NTM infection in individuals with CF as an initial step in optimising management for this challenging condition. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

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

International Nuclear Information System (INIS)

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

1984-01-01

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 14 CO 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 14 CO 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

atpE gene as a new useful specific molecular target to quantify Mycobacterium in environmental samples

Science.gov (United States)

2013-01-01

Background The environment is the likely source of many pathogenic mycobacterial species but detection of mycobacteria by bacteriological tools is generally difficult and time-consuming. Consequently, several molecular targets based on the sequences of housekeeping genes, non-functional RNA and structural ribosomal RNAs have been proposed for the detection and identification of mycobacteria in clinical or environmental samples. While certain of these targets were proposed as specific for this genus, most are prone to false positive results in complex environmental samples that include related, but distinct, bacterial genera. Nowadays the increased number of sequenced genomes and the availability of software for genomic comparison provide tools to develop novel, mycobacteria-specific targets, and the associated molecular probes and primers. Consequently, we conducted an in silico search for proteins exclusive to Mycobacterium spp. genomes in order to design sensitive and specific molecular targets. Results Among the 3989 predicted proteins from M. tuberculosis H37Rv, only 11 proteins showed 80% to 100% of similarity with Mycobacterium spp. genomes, and less than 50% of similarity with genomes of closely related Corynebacterium, Nocardia and Rhodococcus genera. Based on DNA sequence alignments, we designed primer pairs and a probe that specifically detect the atpE gene of mycobacteria, as verified by quantitative real-time PCR on a collection of mycobacteria and non-mycobacterial species. The real-time PCR method we developed was successfully used to detect mycobacteria in tap water and lake samples. Conclusions The results indicate that this real-time PCR method targeting the atpE gene can serve for highly specific detection and precise quantification of Mycobacterium spp. in environmental samples. PMID:24299240

Inherited and acquired immunodeficiencies underlying tuberculosis in childhood

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Boisson-Dupuis, Stéphanie; Bustamante, Jacinta; El-Baghdadi, Jamila; Camcioglu, Yildiz; Parvaneh, Nima; Azbaoui, Safaa El; Agader, Aomar; Hassani, Amal; Hafidi, Naima El; Mrani, Nidal Alaoui; Jouhadi, Zineb; Ailal, Fatima; Najib, Jilali; Reisli, Ismail; Zamani, Adil; Yosunkaya, Sebnem; Gulle-Girit, Saniye; Yildiran, Alisan; Cipe, Funda Erol; Torun, Selda Hancerli; Metin, Ayse; Atikan, Basak Yildiz; Hatipoglu, Nevin; Aydogmus, Cigdem; Kilic, Sara Sebnem; Dogu, Figen; Karaca, Neslihan; Aksu, Guzide; Kutukculer, Necil; Keser-Emiroglu, Melike; Somer, Ayper; Tanir, Gonul; Aytekin, Caner; Adimi, Parisa; Mahdaviani, Seyed Alireza; Mamishi, Setareh; Bousfiha, Aziz; Sanal, Ozden; Mansouri, Davood; Casanova, Jean-Laurent; Abel, Laurent

2015-01-01

Summary Tuberculosis (TB), caused by Mycobacterium tuberculosis (M.tb) and a few related mycobacteria, is a devastating disease, killing more than a million individuals per year worldwide. However, its pathogenesis remains largely elusive, as only a small proportion of infected individuals develop clinical disease either during primary infection or during reactivation from latency or secondary infection. Subacute, hematogenous, and extrapulmonary disease tends to be more frequent in infants, children, and teenagers than in adults. Life-threatening primary TB of childhood can result from known acquired or inherited immunodeficiencies, although the vast majority of cases remain unexplained. We review here the conditions conferring a predisposition to childhood clinical diseases caused by mycobacteria, including not only M.tb but also weakly virulent mycobacteria, such as BCG vaccines and environmental mycobacteria. Infections with weakly virulent mycobacteria are much rarer than TB, but the inherited and acquired immunodeficiencies underlying these infections are much better known. Their study has also provided genetic and immunological insights into childhood TB, as illustrated by the discovery of single-gene inborn errors of IFN-γ immunity underlying severe cases of TB. Novel findings are expected from ongoing and future human genetic studies of childhood TB in countries that combine a high proportion of consanguineous marriages, a high incidence of TB, and an excellent clinical care, such as Iran, Morocco, and Turkey. PMID:25703555

Detection and differentiation of Mycobacterium tuberculosis and nontuberculous mycobacterial isolates by real-time PCR.

Science.gov (United States)

Shrestha, Nabin K; Tuohy, Marion J; Hall, Gerri S; Reischl, Udo; Gordon, Steven M; Procop, Gary W

2003-11-01

Mycobacteria cause a variety of illnesses that differ in severity and public health implications. The differentiation of Mycobacterium tuberculosis from nontuberculous mycobacteria (NTM) is of primary importance for infection control and choice of antimicrobial therapy. Despite advances in molecular diagnostics, the ability to rapidly diagnose M. tuberculosis infections by PCR is still inadequate, largely because of the possibility of false-negative reactions. We designed and validated a real-time PCR for mycobacteria by using the LightCycler system with 18 reference strains and 168 clinical mycobacterial isolates. All clinically significant mycobacteria were detected; the mean melting temperatures (with 99.9% confidence intervals [99.9% CI] in parentheses) for the different mycobacteria were as follows: M. tuberculosis, 64.35 degrees C (63.27 to 65.42 degrees C); M. kansasii, 59.20 degrees C (58.07 to 60.33 degrees C); M. avium, 57.82 degrees C (57.05 to 58.60 degrees C); M. intracellulare, 54.46 degrees C (53.69 to 55.23 degrees C); M. marinum, 58.91 degrees C (58.28 to 59.55 degrees C); rapidly growing mycobacteria, 53.09 degrees C (50.97 to 55.20 degrees C) or 43.19 degrees C (42.19 to 44.49 degrees C). This real-time PCR assay with melting curve analysis consistently accurately detected and differentiated M. tuberculosis from NTM. Detection of an NTM helps ensure that the negative result for M. tuberculosis is a true negative. The specific melting temperature also provides a suggestion of the identity of the NTM present, when the most commonly encountered mycobacterial species are considered. In a parallel comparison, both the LightCycler assay and the COBAS Amplicor M. tuberculosis assay correctly categorized 48 of 50 specimens that were proven by culture to contain M. tuberculosis, and the LightCycler assay correctly characterized 3 of 3 specimens that contained NTM.

Use of RODAC plates to measure containment of Mycobacterium tuberculosis in a Class IIB biosafety cabinet during routine operations

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Géraldine Daneau

2016-01-01

Conclusion: RODAC plates detect mycobacteria at low numbers of microorganisms. In addition, this method allowed us to show that 70% ethanol does not reliably kill mycobacteria when applied for 5min to a dried surface, and that MTB bacilli may arrive outside a Class II BSC during routine practice, although the route could not be documented.

Mycobacteria and TB

National Research Council Canada - National Science Library

Kaufmann, S. H. E. (Stephan H. E.); Hahn, Helmut

2003-01-01

.... Scientists investigating the epidemiology, immunology and molecular biology of TB or engaged in vaccine and drug development as well as physicians and social workers treating TB patients will benefit...

Nontuberculous Mycobacteria (NTM)

Science.gov (United States)

... NTM) Infections Program NTM Center of Excellence Our Specialists Shannon H. Kasperbauer, MD + × Shannon H. Kasperbauer, MD ... URL based on the top item shown if (Math.abs(scroll_pos - last_scroll) > $(window).height() * 0. ...

Molecular and immunological characterization of mycobacteria associated with bovine farcy

International Nuclear Information System (INIS)

Kwajok, Victor Loku

2000-01-01

alignment of the sequenced DNA using computer, was clear and showed 16SrDNA similarity values of 99.8-99.9% which corresponded to 7 and 12 nucleotide differences. Immunoassays of the protein antigens of the test strains of Mycobacterium farcinogenese and the anti sera produced from the laboratory animals-guinea pigs gave positive results. Mycobacterium farcingenese isolates produced approximately similar profiles of protein bands

Molecular and immunological characterization of mycobacteria associated with bovine farcy

Energy Technology Data Exchange (ETDEWEB)

Kwajok, Victor Loku [Faculty of Veterinary Sciences, University of Khartoum, Khartoum (Sudan)

2000-07-01

alignment of the sequenced DNA using computer, was clear and showed 16SrDNA similarity values of 99.8-99.9% which corresponded to 7 and 12 nucleotide differences. Immunoassays of the protein antigens of the test strains of Mycobacterium farcinogenese and the anti sera produced from the laboratory animals-guinea pigs gave positive results. Mycobacterium farcingenese isolates produced approximately similar profiles of protein bands.

Performance of the Ogawa-Kudoh method for isolation of mycobacteria in a laboratory with large-scale workload Rendimiento del método de Ogawa - Kudoh para el aislamiento de micobacterias en un laboratorio con trabajo a gran escala

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C. Rivas

2010-06-01

Full Text Available In Uruguay (population 3,323,906; notified tuberculosis incidence 18.4/100,000, virtually all 30,000 samples yearly collected for mycobacterial culture countrywide are processed in a central laboratory. An average of 110 samples are routinely shipped daily and maintained 48-96 hours at room temperature until cultured on Löwenstein-Jensen slants using the standard NALC-NaOH decontamination procedure. The much simpler Kudoh decontamination/culture method -swab and Ogawa (acidified medium- was compared with NALC-NaOH/Löwenstein-Jensen for isolation of mycobacteria from sputa under routine conditions. To this aim, 784 sputum samples were cultured by both methods in the summertime. Gross agreement was 0.99, kappa: 1. Kudoh performance was as follows: sensitivity 100% and accuracy 98.9%. Assays using a modified culture medium, different decontamination times and NaOH concentrations showed the versatility of this procedure. Thus, the Kudoh method is suitable for culturing mycobacteria from naturally contaminated samples even when processing is deferred two to four days after collection.En Uruguay (3 323 906 habitantes; incidencia notificada de tuberculosis 18,4/100 000, más del 95% de los cultivos para micobacterias de todo el país (30 000 por año son procesados en un laboratorio central. Un promedio de 110 muestras de expectoración diarias son enviadas y mantenidas a temperatura ambiente durante 48-96 horas hasta ser procesadas por el método de descontaminación con NALC-NaOH y cultivadas en medio Löwenstein-Jensen. Con el objeto de evaluar el método de Kudoh (hisopo y medio de Ogawa acidificado como una alternativa más sencilla para el cultivo de micobacterias en este tipo de muestras, se procesaron por ambos métodos 784 esputos durante los meses de verano, a fin de comparar los resultados obtenidos. La concordancia bruta fue de 0.99; el coeficiente kappa fue 1. El método de Kudoh mostró una sensibilidad del 100% y una exactitud del 98

¹³C metabolic flux analysis identifies an unusual route for pyruvate dissimilation in mycobacteria which requires isocitrate lyase and carbon dioxide fixation.

Directory of Open Access Journals (Sweden)

Dany J V Beste

2011-07-01

Full Text Available Mycobacterium tuberculosis requires the enzyme isocitrate lyase (ICL for growth and virulence in vivo. The demonstration that M. tuberculosis also requires ICL for survival during nutrient starvation and has a role during steady state growth in a glycerol limited chemostat indicates a function for this enzyme which extends beyond fat metabolism. As isocitrate lyase is a potential drug target elucidating the role of this enzyme is of importance; however, the role of isocitrate lyase has never been investigated at the level of in vivo fluxes. Here we show that deletion of one of the two icl genes impairs the replication of Mycobacterium bovis BCG at slow growth rate in a carbon limited chemostat. In order to further understand the role of isocitrate lyase in the central metabolism of mycobacteria the effect of growth rate on the in vivo fluxes was studied for the first time using ¹³C-metabolic flux analysis (MFA. Tracer experiments were performed with steady state chemostat cultures of BCG or M. tuberculosis supplied with ¹³C labeled glycerol or sodium bicarbonate. Through measurements of the ¹³C isotopomer labeling patterns in protein-derived amino acids and enzymatic activity assays we have identified the activity of a novel pathway for pyruvate dissimilation. We named this the GAS pathway because it utilizes the Glyoxylate shunt and Anapleurotic reactions for oxidation of pyruvate, and Succinyl CoA synthetase for the generation of succinyl CoA combined with a very low flux through the succinate--oxaloacetate segment of the tricarboxylic acid cycle. We confirm that M. tuberculosis can fix carbon from CO₂ into biomass. As the human host is abundant in CO₂ this finding requires further investigation in vivo as CO₂ fixation may provide a point of vulnerability that could be targeted with novel drugs. This study also provides a platform for further studies into the metabolism of M. tuberculosis using ¹³C-MFA.

[Severe course of a rare non-tuberculous Mycobacteriosis (M. haemophilum) of the hand - case report and strategic comments].

Science.gov (United States)

Schumacher, O; Dabernig, J; Nenadic, I; Ingianni, G; Cedidi, C

2008-10-01

Mycobacterium haemophilum belongs to the group of atypical mycobacteria and is rarely reported as a cause of upper extremity and hand infections. It is of low virulence. The bacterium seems to be ubiquitous. Sources and mechanism of infection are poorly defined. A 48-year-old female patient was admitted with chronic flexor tendon synovitis of the left palm and distal forearm site. Three debridements were carried out and wound swabs were taken. No proof of bacterial colonisation was found. Histologically a granulomatous infection with Langerhans cells was revealed. Effectively calculated monotherapy with ciprofloxacin was begun. Six weeks postoperatively Mycobacterium haemophilum was cultivated in a colaboration with the National Reference Centre for Mycobacteria in Borstel. Medication was changed to triple therapy with clarithromycin, ethambutol and rifabutin. The patient could carry out her daytime job three months postoperatively. One year after first admission functional impairment needed to be treated by scar excision and radical flexor tendon tendolysis. The palmar defect was resurfaced by using a transmetacarpal DMCA 2 flap at the same time. An almost full range of motion was achieved with intensive hand and physiotherapy after a total treatment period of 15 months. Patients with upper extremity infections caused by atypical Mycobacteria need qualified hand-surgical care. The decision about need and kind of medicamentous treatment is based on germ differentiation and should be made in cooperation with the National Reference Centre for Mycobacteria in Borstel. To shorten the diagnostic gap between first admission and detection of Mycobacteria in hand infections with a non-typical course of disease we suggest a standardised approach.

Intact molecular characterization of cord factor (trehalose 6,6'-dimycolate) from nine species of mycobacteria by MALDI-TOF mass spectrometry.

Science.gov (United States)

Fujita, Yukiko; Naka, Takashi; McNeil, Michael R; Yano, Ikuya

2005-10-01

Cord factor (trehalose 6,6'-dimycolate, TDM) is an unique glycolipid with a trehalose and two molecules of mycolic acids in the mycobacterial cell envelope. Since TDM consists of two molecules of very long branched-chain 3-hydroxy fatty acids, the molecular mass ranges widely and in a complex manner. To characterize the molecular structure of TDM precisely and simply, an attempt was made to determine the mycolic acid subclasses of TDM and the molecular species composition of intact TDM by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry for the first time. The results showed that less than 1 microg mycolic acid methyl ester of TDM from nine representative species of mycobacteria and TDM from the same species was sufficient to obtain well-resolved mass spectra composed of pseudomolecular ions [M+Na]+. Although the mass ion distribution was extremely diverse, the molecular species of each TDM was identified clearly by constructing a molecular ion matrix consisting of the combination of two molecules of mycolic acids. The results showed a marked difference in the molecular structure of TDM among mycobacterial species and subspecies. TDM from Mycobacterium tuberculosis (H37Rv and Aoyama B) showed a distinctive mass pattern and consisted of over 60 molecular ions with alpha-, methoxy- and ketomycolate. TDM from Mycobacterium bovis BCG Tokyo 172 similarly showed over 35 molecular ions, but that from M. bovis BCG Connaught showed simpler molecular ion clusters consisting of less than 35 molecular species due to a complete lack of methoxymycolate. Mass ions due to TDM from M. bovis BCG Connaught and Mycobacterium kansasii showed a biphasic distribution, but the two major peaks of TDM from M. kansasii were shifted up two or three carbon units higher compared with M. bovis BCG Connaught. Within the rapid grower group, in TDM consisting of alpha-, keto- and wax ester mycolate from Mycobacterium phlei and Mycobacterium flavescens, the

Stable, fertile, high polyhydroxyalkanoate producing plants and methods of producing them

Energy Technology Data Exchange (ETDEWEB)

Bohmert-Tatarev, Karen; McAvoy, Susan; Peoples, Oliver P.; Snell, Kristi D.

2015-08-04

Transgenic plants that produce high levels of polyhydroxybutyrate and methods of producing them are provided. In a preferred embodiment the transgenic plants are produced using plastid transformation technologies and utilize genes which are codon optimized. Stably transformed plants able to produce greater than 10% dwt PHS in tissues are also provided.

Dendritic cells that phagocytose apoptotic macrophages loaded with mycobacterial antigens activate CD8 T cells via cross-presentation

OpenAIRE

Espinosa-Cueto, Patricia; Magallanes-Puebla, Alejandro; Castellanos, Carlos; Mancilla, Raul

2017-01-01

While homeostatic apoptosis is immunologically silent, macrophage apoptosis during Mycobacterium tuberculosis infection can potentially induce an immune response against the mycobacteria. To examine the role of dendritic cells in this response, macrophage apoptosis was induced by incubating the macrophage with cell wall extracts of mycobacteria expressing LpqH. The apoptogenic proteins of the cell wall extracts were engulfed by the macrophage and then were translocated from the cytosol to the...

Identification of the translational start site of codon-optimized mCherry in Mycobacterium tuberculosis

OpenAIRE

Carroll, Paul; Muwanguzi-Karugaba, Julian; Melief, Eduard; Files, Megan; Parish, Tanya

2014-01-01

Background Fluorescent proteins are used widely as reporter genes in many organisms. We previously codon-optimized mCherry for Mycobacterium tuberculosis and generated expression constructs with high level expression in mycobacteria with multiple uses in vitro and in vivo. However, little is known about the expression of fluorescent proteins in mycobacteria and the translational start codon for mCherry has not been experimentally determined. Results We determined the translational start site ...

Asymmetry and aging of mycobacterial cells leads to variable growth and antibiotic susceptibility

OpenAIRE

Aldridge, Bree B.; Fernandez-Suarez, Marta; Heller, Danielle; Ambravaneswaran, Vijay; Irimia, Daniel; Toner, Mehmet; Fortune, Sarah

2011-01-01

Cells use both deterministic and stochastic mechanisms to generate cell–to-cell heterogeneity, which enables the population to better withstand environmental stress. Here we show that, within a clonal population of mycobacteria, there is significant deterministic heterogeneity in elongation rate that arises because mycobacteria grow in an unusual, unipolar fashion. Division of the asymmetrically growing mother cell gives rise to daughter cells that differ in elongation rate and size. Because ...

Important role of the nucleotide excision repair pathway in Mycobacterium smegmatis in conferring protection against commonly encountered DNA-damaging agents.

Science.gov (United States)

Kurthkoti, Krishna; Kumar, Pradeep; Jain, Ruchi; Varshney, Umesh

2008-09-01

Mycobacteria are an important group of human pathogens. Although the DNA repair mechanisms in mycobacteria are not well understood, these are vital for the pathogen's persistence in the host macrophages. In this study, we generated a null mutation in the uvrB gene of Mycobacterium smegmatis to allow us to compare the significance of the nucleotide excision repair (NER) pathway with two important base excision repair pathways, initiated by uracil DNA glycosylase (Ung) and formamidopyrimidine DNA glycosylase (Fpg or MutM), in an isogenic strain background. The strain deficient in NER was the most sensitive to commonly encountered DNA-damaging agents such as UV, low pH, reactive oxygen species, hypoxia, and was also sensitive to acidified nitrite. Taken together with previous observations on NER-deficient M. tuberculosis, these results suggest that NER is an important DNA repair pathway in mycobacteria.

TUBERCULOSIS

OpenAIRE

Tarik Bajrović; Mahmud Nurkić; Šukrija Zvizdić

2013-01-01

Tuberculosis, known as the "White Plague" in the early 19th century, is the infectious disease, which is being researched today even in some of the most developed countries in the world. Epidemiological- epizootiological research points to the importance of pasteurizing milk as well as the transmission in aerosolized droplets in humans and animals. Mycobacterium tuberculosis (Mtb), M. bovis, M. africanum and M. microti are the mycobacteria that cause tuberculosis. Other mycobacteria cause dis...

CCT`s in a deregulated environment: A producer`s perspective

Energy Technology Data Exchange (ETDEWEB)

Edmonds, R.F. Jr.; Fayssoux, J.O. [Duke Power Co., Charlotte, NC (United States)

1997-12-31

The US electric industry will be deregulated (or substantially re-regulated) within 5 years. Several states, including California, Rhode Island, and New Hampshire, already have passed legislation to introduce competition into the electric markets before the year 2000. As this trend sweeps across the country, the resulting competitive market for generation will reward the lowest cost producers and force high cost producers out of the market. As a result, at least in the short run, it may be very difficult for new power plants employing Clean Coal Technologies (CCTs) to compete. This paper discusses a producer`s perspective of the new competitive market, and suggests several short and long term strategies and niches for CCTs.

[Cutaneous infection by Mycobacterium fortuitum]  Infeccion cutanea por Mycobacterium fortuitum

Directory of Open Access Journals (Sweden)

Verónica Rotela

2017-10-01

Full Text Available Mycobacteria are aerobic, non-spore forming, gram positive, acid-fast bacilli, which affect skin, subcutaneous tissue, and other organs and systems. Mycobacterium fortuitum produces cellulitis, abscesses, papules-pustules, nodules and ulcers with serosanguinolent, purulent material, and subcutaneous necrosis. A 61-year-old woman, presents a case of two months of evolution that begins with reddish grain from an insect sting. After immersion in the Mexican Sea, it worsens, increases in quantity, is blistered and has brownish secretion; Physical examination shows erythematous plaque, with punctate orifices with hematic and meliceric crusts; Pustules and satellite papules, on the anterior aspect of the right leg. Histopathology: Suppurative dermal granulomas, centered by acute leukocyte infiltrate, with liquefactive tissue necrosis, surrounded by chronic inflammation with macrophages, plasma cells, lymphocytes, multinucleated giant cells. The first skin culture returns negative; in the second skin culture, fast-growing, non-pigmented atypical mycobacteria. Molecular detection is performed by Polymerase Chain Reaction: Mycobacterium fortuitum. Treatment with Ciprofloxacin 500 mg every 12 hours, with resolution of the table to the eighth month. A case of cutaneous infection by Mycobacterium fortuitum, related to the immersion in the sea and corals, whose diagnostic process has been difficult and was achieved by techniques of advanced molecular biology.

Mycobacterium chelonae empyema with bronchopleural fistula in an immunocompetent patient

International Nuclear Information System (INIS)

Wali, Siraj

2009-01-01

Mycobacterium Calhoun is one of the rapidly growing mycobacteria that rarely cause lung disease. M chelonae more commonly causes skin and soft tissue infections primarily in immunosuppressed individuals. Thoracic empyema caused by rapidly growing mycobacteria and complicated with bronchopleural fistula is rarely reported, especially in immunocompetent patients. In this article we report the first immunocompetent Arabian patient presented with M chelonae- related empyema with bronchopleural fistula which mimics, clinically and radiologically, empyema caused by Mycobacterium tuberculosis. (author)

The use of real-time polymerase chain reaction for rapid diagnosis of skeletal tuberculosis.

Science.gov (United States)

Kobayashi, Naomi; Fraser, Thomas G; Bauer, Thomas W; Joyce, Michael J; Hall, Gerri S; Tuohy, Marion J; Procop, Gary W

2006-07-01

We identified Mycobacterium tuberculosis DNA using real-time polymerase chain reaction on a specimen from an osteolytic lesion of a femoral condyle, in which the frozen section demonstrated granulomas. The process was much more rapid than is possible with culture. The rapid detection of M tuberculosis and the concomitant exclusion of granulomatous disease caused by nontuberculous mycobacteria or systemic fungi are necessary to appropriately treat skeletal tuberculosis. The detection and identification of M tuberculosis by culture may require several weeks using traditional methods. The real-time polymerase chain reaction method used has been shown to be rapid and reliable, and is able to detect and differentiate both tuberculous and nontuberculous mycobacteria. Real-time polymerase chain reaction may become a diagnostic standard for the evaluation of clinical specimens for the presence of mycobacteria; this case demonstrates the potential utility of this assay for the rapid diagnosis of skeletal tuberculosis.

Mycobacteria and innate cells

Indian Academy of Sciences (India)

PRAKASH KUMAR G

Effective adaptive immune responses to pathogenic and ... Protective immunity against mycobacterial infections such as Mycobacterium tuberculosis is mediated by interactions ..... 4. γδ T cells as special guests in the antimycobacterial.

Of Microsoft and Mycobacteria

Directory of Open Access Journals (Sweden)

Hans Pasterkamp

2001-01-01

Full Text Available Bill Gates should have run for President of the United States. Not only would he have been a candidate with some legitimate claim to the Internet, but his call for a major increase in funding for new defence systems would have been supported by the general public, both at home and abroad. The founder of Microsoft himself spent US$1.44 billion last year to support the fight against global health threats from infectious diseases such as AIDS, malaria and tuberculosis (TB. This contribution from the Bill and Melinda Gates Foundation was more than one-quarter of the total amount that all industrialized nations together raised for this cause.

Mycobacterium fortuitum and anaerobic breast abscess following nipple piercing: case presentation and review of the literature.

Science.gov (United States)

Bengualid, Victoria; Singh, Veera; Singh, Herpreet; Berger, Judith

2008-05-01

Body piercing has become increasingly prevalent. We describe a case of breast infection with combined mycobacteria and anaerobe following nipple piercing, and review the literature. A 17-year-old female developed a breast abscess 4 months after nipple piercing. Cultures grew Prevotalla melangenica and Mycobacterium fortuitum. She required drainage and antibiotic treatment. Three months into her treatment she stopped her medications, relapsed, and required drainage. Two months later, on antimycobacteria therapy, her wound is healing. Review of the infectious complications of nipple piercing yielded 12 cases, 5 of which had a foreign body. The pathogens isolated (coagulase negative staphylococcus, mycobacteria, streptococcus, anaerobe, and gordonia) are not the usual organisms to be isolated from a breast abscess. This could result from reporting bias or the presence of a foreign body, the nipple ring. The three cases of mycobacteria, in addition to ours, are reviewed. The average age is 22 years. Three to 9 months elapsed between piercing and infection. All cases required drainage. Antimycobacteria therapy was used in three of the four cases for 10 days to 6 months. With the increasing prevalence of body piercing, it is important to document and report infections. We describe a breast abscess following nipple piercing with combined anaerobic and a mycobacterial pathogens. This underscores the need for obtaining cultures including anaerobes and mycobacteria.

Reduction of Acid-Fast and Non-Acid-Fast Bacteria by Point of Use Coagulation-Flocculation-Disinfection

Directory of Open Access Journals (Sweden)

Lisa M. Casanova

2015-11-01

Full Text Available Point of use (POU household water treatment is increasingly being adopted as a solution for access to safe water. Non-tuberculous Mycobacteria (NTM are found in water, but there is little research on whether NTM survive POU treatment. Mycobacteria may be removed by multi-barrier treatment systems that combine processes such as coagulation, settling and disinfection. This work evaluated removal of a non-tuberculous Mycobacterium (Mycobaterium terrae and a Gram-negative non-acid-fast environmental bacterium (Aeromonas hydrophila by combined coagulation-flocculation disinfection POU treatment. Aeromonas hydrophila showed 7.7 log10 reduction in demand free buffer, 6.8 log10 in natural surface water, and 4 log10 reduction in fecally contaminated surface water. Turbidity after treatment was <1 NTU. There was almost no reduction in levels of viable M. terrae by coagulant-flocculant-disinfectant in natural water after 30 minutes. The lack of Mycobacteria reduction was similar for both combined coagulant-flocculant-disinfectant and hypochlorite alone. A POU coagulant-flocculant-disinfectant treatment effectively reduced A. hydrophila from natural surface waters but not Mycobacteria. These results reinforce previous findings that POU coagulation-flocculation-disinfection is effective against gram-negative enteric bacteria. POU treatment and safe storage interventions may need to take into account risks from viable NTM in treated stored water and consider alternative treatment processes to achieve NTM reductions.

Dominance of IMP-4-Producing Enterobacter cloacae among Carbapenemase-Producing Enterobacteriaceae in Australia

Science.gov (United States)

Townell, Nicola; Nimmo, Graeme R.; George, Narelle M.; Robson, Jennifer; Vohra, Renu; Davis, Louise; Heney, Claire; Paterson, David L.

2015-01-01

The prevalence of carbapenemase-producing Enterobacteriaceae (CPE) has been increasing worldwide. blaIMP has been reported to be the predominant carbapenemase-encoding gene within Enterobacteriaceae in Australia. However, there are limited data currently available on CPE from Queensland, Australia. A total of 58 CPE isolates were isolated between July 2009 and March 2014 from Queensland hospitals. The clonality of isolates was determined by Diversilab repetitive sequence-based PCR. The isolates were investigated for the resistance mechanisms carbapenemase, extended-spectrum β-lactamase, and AmpC β-lactamase and for aminoglycoside resistance and plasmid-mediated quinolone resistance genes by PCR. The plasmid types associated with carbapenemase-encoding genes were characterized. The majority of the CPE were Enterobacter cloacae (n = 29). The majority of Queensland CPE isolates were IMP producers and comprised 11 species (n = 48). Nine NDM-producing Enterobacteriaceae were identified. One NDM-producing Klebsiella pneumoniae isolate coproduced OXA-48. One K. pneumoniae isolate was an OXA-181 producer. The incidence of IMP producers increased significantly in 2013. blaIMP-4 was found in all IMP-producing isolates. blaTEM, qnrB, and aacA4 were common among IMP-4 producers. The HI2 (67%) and L/M (21%) replicons were associated with blaIMP-4. All HI2 plasmids were of sequence type 1 (ST1). All but one of the NDM producers possessed blaCTX-M-15. The 16S rRNA methylase genes found among NDM producers were armA, rmtB, rmtC, and rmtF. The substantial increase in the prevalence of CPE in Queensland has been associated mainly with the emergence E. cloacae strains possessing HI2 plasmids carrying blaIMP-4 over the past 2 years. The importation of NDM producers and/or OXA-48-like producers in patients also contributed to the increased emergence of CPE. PMID:25918153

Non-tuberculous mycobacteria I: one year clinical isolates identification in Tertiary Hospital Aids Reference Center, Rio de Janeiro, Brazil, in pre highly active antiretroviral therapy era

Directory of Open Access Journals (Sweden)

Ferreira Rosa Maria Carvalho

2002-01-01

Full Text Available The aim of this study was to determine the prevalence of non-tuberculous mycobacteria (NTM isolates at University Hospital, Reference Center for Aids in Rio de Janeiro, Brazil, during one year. We used standard biochemical tests for species identification and IS1245 PCR amplification was applied as a Mycobacterium avium specific identification marker. Four hundred and four specimens from 233 patients yielded acid-fast bacilli growth. M. tuberculosis was identified in 85% of the patients and NTM in 15%. NTM disseminated infection was a common event correlated with human immunodeficiency virus (HIV infected patients and only in HIV negative patients the source of NTM was non sterile site. M. avium complex (MAC was biochemically identified in 57.8% (49/83 of NTM isolates, most of them from sterile sites (75.5%, and in 94% (46/49 the IS 1245 marker specific for M. avium was present. Twenty NTM strains showed a MAC biochemical pattern with the exception of a urease-positive (99% of MAC are urease-negative, however IS1245 was detected in 96% of the strains leading to their identification as M. avium. In this group differences in NTM source was not significant. The second most frequently isolated NTM was identified as M. scrofulaceum (7.2%, followed by M. terrae (3.6%, M. gordonae (2.4%, M. chelonae (1.2%, M. fortuitum (1.2% and one strain which could not be identified. All were IS1245 negative except for one strain identified as M. scrofulaceum. It is interesting to note that non-sterile sites were the major source of these isolates (92.8%. Our finding indicated that M. avium is still the major atypical species among in the MAC isolates recovered from Brazilian Aids patients without highty active antiretroviral therapy schema. Some discrepancies were seen between the identification methods and further investigations must be done to better characterize NTM isolates using other phenotypic and genotypic methods.

Producing charcoal from wastes

Energy Technology Data Exchange (ETDEWEB)

Pogorelov, V.A.

1983-01-01

Experimental works to use wood wastes for producing charcoal are examined, which are being conducted in the Sverdlovsk assembly and adjustment administration of Soyuzorglestekhmontazh. A wasteless prototype installation for producing fine charcoal is described, along with its subsequent briqueting, which is made on the basis of units which are series produced by the factories of the country. The installation includes subassemblies for preparing and drying the raw material and for producing the charcoal briquets. In the opinion of specialists, the charcoal produced from the wastes may be effectively used in ferrous and nonferrous metallurgy and in the production of pipes.

Mycobacterium spp. in wild game in Slovenia.

Science.gov (United States)

Pate, Mateja; Zajc, Urška; Kušar, Darja; Žele, Diana; Vengušt, Gorazd; Pirš, Tina; Ocepek, Matjaž

2016-02-01

Wildlife species are an important reservoir of mycobacterial infections that may jeopardise efforts to control and eradicate bovine tuberculosis (bTB), caused by Mycobacterium bovis. Slovenia is officially free of bTB, but no data on the presence of mycobacteria in wild animals has been reported. In this study, samples of liver and lymph nodes were examined from 306 apparently healthy free-range wild animals of 13 species in Slovenia belonging to the families Cervidae, Suidae, Canidae, Mustelidae and Bovidae. Mycobacteria were isolated from 36/306 (11.8%) animals (red deer, roe deer, fallow deer, wild boar and jackal) and identified by PCR, commercial diagnostic kits and sequencing. Non-tuberculous mycobacteria identified in five species were Mycobacterium peregrinum, M. avium subsp. hominissuis, M. intracellulare, M. confluentis, M. fortuitum, M. terrae, M. avium subsp. avium, M. celatum, M. engbaekii, M. neoaurum, M. nonchromogenicum and M. vaccae. Copyright © 2015 Elsevier Ltd. All rights reserved.

Consumers and Producers

NARCIS (Netherlands)

E. Maira (Elisa)

2018-01-01

markdownabstractIn the last few decades, advances in information and communication technology have dramatically changed the way consumers and producers interact in the marketplace. The Internet and social media have torn down the information barrier between producers and consumers, leading to

Biologically produced sulfur

NARCIS (Netherlands)

Kleinjan, W.E.; Keizer, de A.; Janssen, A.J.H.

2003-01-01

Sulfur compound oxidizing bacteria produce sulfur as an intermediate in the oxidation of hydrogen sulfide to sulfate. Sulfur produced by these microorganisms can be stored in sulfur globules, located either inside or outside the cell. Excreted sulfur globules are colloidal particles which are

New and bioactive compounds from Streptomyces strains residing in the wood of Celastraceae.

Science.gov (United States)

Pullen, Christian; Schmitz, Petra; Meurer, Kristina; Bamberg, Daniel D v; Lohmann, Stephanie; De Castro França, Suzelei; Groth, Ingrid; Schlegel, Brigitte; Möllmann, Ute; Gollmick, Friedrich; Gräfe, Udo; Leistner, Eckhard

2002-11-01

Wood from three different plants of the Celastraceae growing in their natural habitats in Brazil (Maytenus aquifolia Mart.) and South Africa [Putterlickia retrospinosa van Wyk and Mostert, P. verrucosa (E. Meyer ex Sonder) Szyszyl.] was established as a source of endophytic bacteria using a medium selective for actinomycetes. Two isolates were identified as Streptomyces setonii and S. sampsonii whereas two others were not assignable to any of the known Streptomyces species. They were preliminarily named Streptomyces Q21 and Streptomyces MaB-QuH-8. The latter strain produces a new chloropyrrol and chlorinated anthracyclinone. The chloropyrrol showed high activity against a series of multiresistent bacteria and mycobacteria.

MYCOBACTERIUM COMPLEX IDENTIFICATION BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Directory of Open Access Journals (Sweden)

S.A HAWAII

2001-12-01

Full Text Available Introduction: There are different ways for identification of Mycobacteria. One of the most sensitive method is HPLC of phenacyl esters of mycolic acids of Mycobacteria for rapid identification of them after their primary cultures. This study uses HPLC for rapid identification and dissociation of Mycobacterium tuberculosis complex. Methods: In this study we use HPLC patterns of mycolic acids for identification three important species of mycobacteria (M. tuberculosis, M. bovis, M. bovis BCG from other mycobacterial species. All the strains were obtained from Tuberculosis and Pulmonary Diseases Research Center. HPLC conditions was as follows: HPLC: Model 1200 Cecil, Column: URP C-18 25X4.6 mm, Detector: U.V variable wave length at 254 nm, Elution: Gradient of methanol/chloroform. Flow rate: 2.5 ml/min. Results: HPLC leads to obtaining chromatograms which on its X-axis retention times (of different peaks which exist in the sample and on its Y-axis U.V absorbance (of these peaks were drown. These chromatograms in M. bovis and M. tuberculosis samples are similar with each other but differs from BCG ones. Discussion: On the basis of different retention times and numbers of the peaks which present in each chromatogram, we can differentiate between M. bovis, M. tuberculosis and BCG from other Mycobacteria. Also, with this method we can identify BCG from M. bovis and M. tuberculosis (because BCG has 9 and M. bovis and M. tuberculosis has 7 characteristic peaks in their chromatograms.

Mycobacterial secretion systems ESX-1 and ESX-5 play distinct roles in host cell death and inflammasome activation

KAUST Repository

Abdallah, Abdallah

2011-09-28

During infection of humans and animals, pathogenic mycobacteria manipulate the host cell causing severe diseases such as tuberculosis and leprosy. To understand the basis of mycobacterial pathogenicity, it is crucial to identify the molecular virulence mechanisms. In this study, we address the contribution of ESX-1 and ESX-5 - two homologous type VII secretion systems of mycobacteria that secrete distinct sets of immune modulators - during the macrophage infection cycle. Using wild-type, ESX-1- and ESX-5-deficient mycobacterial strains, we demonstrate that these secretion systems differentially affect subcellular localization and macrophage cell responses. We show that in contrast to ESX-1, the effector proteins secreted by ESX-5 are not required for the translocation of Mycobacterium tuberculosis or Mycobacterium marinum to the cytosol of host cells. However, the M. marinum ESX-5 mutant does not induce inflammasome activation and IL-1b activation. The ESX-5 system also induces a caspase-independent cell death after translocation has taken place. Importantly, by means of inhibitory agents and small interfering RNA experiments, we reveal that cathepsin B is involved in both the induction of cell death and inflammasome activation upon infection with wild-type mycobacteria. These results reveal distinct roles for two different type VII secretion systems during infection and shed light on how virulent mycobacteria manipulate the host cell in various ways to replicate and spread. Copyright © 2011 by The American Association of Immunologists, Inc.

Producing metallurgic coke

Energy Technology Data Exchange (ETDEWEB)

Abe, T.; Isida, K.; Vada, Y.

1982-11-18

A mixture of power producing coals with coal briquets of varying composition is proposed for coking in horizontal chamber furnaces. The briquets are produced from petroleum coke, coal fines or semicoke, which make up less than 27 percent of the mixture to be briquetted and coals with a standard coking output of volatile substances and coals with high maximal Gizeler fluidity. The ratio of these coals in the mixture is 0.6 to 2.1 or 18 to 32 percent, respectively. Noncaking or poorly caking coals are used as the power producing coals. The hardness of the obtained coke is DJ15-30 = 90.5 to 92.7 percent.

Differentiation of Mycobacterium tuberculosis complex from non-tubercular mycobacteria by nested multiplex PCR targeting IS6110, MTP40 and 32kD alpha antigen encoding gene fragments.

Science.gov (United States)

Sinha, Pallavi; Gupta, Anamika; Prakash, Pradyot; Anupurba, Shampa; Tripathi, Rajneesh; Srivastava, G N

2016-03-12

Control of the global burden of tuberculosis is obstructed due to lack of simple, rapid and cost effective diagnostic techniques that can be used in resource poor-settings. To facilitate the early diagnosis of TB directly from clinical specimens, we have standardized and validated the use of nested multiplex PCR, targeting gene fragments IS6110, MTP40 and 32kD α-antigen encoding genes specific for Mycobacterium tuberculosis complex and non-tubercular mycobacteria (NTM), in comparison to smear microscopy, solid culture and single step multiplex PCR. The results were evaluated in comparison to a composite reference standard (CRS) comprising of microbiological results (smear and culture), clinical, radiological and cytopathological findings, clinical treatment and response to anti-tubercular therapy. The nested multiplex PCR (nMPCR) assay was evaluated to test its utility in 600 (535 pulmonary and 65 extra-pulmonary specimens) clinically suspected TB cases. All specimens were processed for smear, culture, single step multiplex PCR and nested multiplex PCR testing. Out of 535 screened pulmonary and 65 extra-pulmonary specimens, 329 (61.5%) and 19 (29.2%) cases were culture positive for M. tuberculosis. Based on CRS, 450 patients had "clinical TB" (definitive-TB, probable-TB and possible-TB). Remaining 150 were confirmed "non-TB" cases. For culture, the sensitivity was low, 79.3% for pulmonary and 54.3% for extra-pulmonary cases. The sensitivity and specificity results for nMPCR test were evaluated taken composite reference standard as a gold standard. The sensitivity of the nMPCR assay was 97.1% for pulmonary and 91.4% for extra-pulmonary TB cases with specificity of 100% and 93.3% respectively. Nested multiplex PCR using three gene primers is a rapid, reliable and highly sensitive and specific diagnostic technique for the detection and differentiation of M. tuberculosis complex from NTM genome and will be useful in diagnosing paucibacillary samples. Nested multiplex

Insights into the smooth-to-rough transitioning in Mycobacterium bolletii unravels a functional Tyr residue conserved in all mycobacterial MmpL family members.

Science.gov (United States)

Bernut, Audrey; Viljoen, Albertus; Dupont, Christian; Sapriel, Guillaume; Blaise, Mickaël; Bouchier, Christiane; Brosch, Roland; de Chastellier, Chantal; Herrmann, Jean-Louis; Kremer, Laurent

2016-03-01

In mycobacteria, MmpL proteins represent key components that participate in the biosynthesis of the complex cell envelope. Whole genome analysis of a spontaneous rough morphotype variant of Mycobacterium abscessus subsp. bolletii identified a conserved tyrosine that is crucial for the function of MmpL family proteins. Isogenic smooth (S) and rough (R) variants differed by a single mutation linked to a Y842H substitution in MmpL4a. This mutation caused a deficiency in glycopeptidolipid production/transport in the R variant and a gain in the capacity to produce cords in vitro. In zebrafish, increased virulence of the M. bolletii R variant over the parental S strain was found, involving massive production of serpentine cords, abscess formation and rapid larval death. Importantly, this finding allowed us to demonstrate an essential role of Tyr842 in several different MmpL proteins, including Mycobacterium tuberculosis MmpL3. Structural homology models of MmpL4a and MmpL3 identified two additional critical residues located in the transmembrane regions TM10 and TM4 that are facing each other. We propose that these central residues are part of the proton-motive force that supplies the energy for substrate transport. Hence, we provide important insights into mechanistic/structural aspects of MmpL proteins as lipid transporters and virulence determinants in mycobacteria. © 2015 John Wiley & Sons Ltd.

Investigation of Functional Activity of Cells in Granulomatous Inflammatory Lesions from Mice with Latent Tuberculous Infection in the New Ex Vivo Model

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Elena Ufimtseva

2013-01-01

Full Text Available The new ex vivo model system measuring functional input of individual granuloma cells to formation of granulomatous inflammatory lesions in mice with latent tuberculous infection has been developed and described in the current study. Monolayer cultures of cells that migrated from individual granulomas were established in the proposed culture settings for mouse spleen and lung granulomas induced by in vivo exposure to BCG vaccine. The cellular composition of individual granulomas was analyzed. The expression of the leukocyte surface markers such as phagocytic receptors CD11b, CD11c, CD14, and CD16/CD32 and the expression of the costimulatory molecules CD80, CD83, and CD86 were tested as well as the production of proinflammatory cytokines (IFNγ and IL-1α and growth factors (GM-CSF and FGFb for cells of individual granulomas. The colocalization of the phagocytic receptors and costimulatory molecules in the surface microdomains of granuloma cells (with and without acid-fast BCG-mycobacteria has also been detected. It was found that some part of cytokine macrophage producers have carried acid-fast mycobacteria. Detected modulation in dynamics of production of pro-inflammatory cytokines, growth factors, and leukocyte surface markers by granuloma cells has indicated continued processes of activation and deactivation of granuloma inflammation cells during the latent tuberculous infection progress in mice.

Investigation of Functional Activity of Cells in Granulomatous Inflammatory Lesions from Mice with Latent Tuberculous Infection in the New Ex Vivo Model

Science.gov (United States)

2013-01-01

The new ex vivo model system measuring functional input of individual granuloma cells to formation of granulomatous inflammatory lesions in mice with latent tuberculous infection has been developed and described in the current study. Monolayer cultures of cells that migrated from individual granulomas were established in the proposed culture settings for mouse spleen and lung granulomas induced by in vivo exposure to BCG vaccine. The cellular composition of individual granulomas was analyzed. The expression of the leukocyte surface markers such as phagocytic receptors CD11b, CD11c, CD14, and CD16/CD32 and the expression of the costimulatory molecules CD80, CD83, and CD86 were tested as well as the production of proinflammatory cytokines (IFNγ and IL-1α) and growth factors (GM-CSF and FGFb) for cells of individual granulomas. The colocalization of the phagocytic receptors and costimulatory molecules in the surface microdomains of granuloma cells (with and without acid-fast BCG-mycobacteria) has also been detected. It was found that some part of cytokine macrophage producers have carried acid-fast mycobacteria. Detected modulation in dynamics of production of pro-inflammatory cytokines, growth factors, and leukocyte surface markers by granuloma cells has indicated continued processes of activation and deactivation of granuloma inflammation cells during the latent tuberculous infection progress in mice. PMID:24198843

Isolation and identification of Mycobacterium bovis in milk from cows in northeastern Brazil

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Joelson Marcolino Ramos

Full Text Available ABSTRACT: Milk samples from 16 cows that tested positive on the tuberculin test in the state of Paraíba, northeastern Brazil, were used for mycobacteria isolation and identification. Mycobacteria were isolated from five (31.25% of the 16 milk samples; three samples were classified as M. bovis, and two as belonging to the Mycobacterium genus. This is probably the first study of isolation and identification of M. bovis in milk from cows in Northeastern Brazil, which suggests that humans are at risk of contamination by ingestion.

7 CFR 1206.16 - Producer.

Science.gov (United States)

2010-01-01

... producing, or causing to be produced, mangos beyond the person's own family use and having value at first... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE MANGO PROMOTION, RESEARCH, AND INFORMATION Mango Promotion, Research, and Information Order Definitions § 1206.16 Producer. Producer means...

Bioavailability of isoflavones from soy products in equol producers and non-producers in Japanese women

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Ayako Miura

2016-12-01

Conclusions: The results in this study suggest that bioavailability of isoflavones are different between equol producers and non-producers, because the 24 h urinary excretion of equol in the equol producers were significantly lower than those in the equol non-producers.

Brookhaven Linac Isotope Producer

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Federal Laboratory Consortium — The Brookhaven Linac Isoptope Producer (BLIP)—positioned at the forefront of research into radioisotopes used in cancer treatment and diagnosis—produces commercially...

Novel Polyoxyethylene-Containing Glycolipids Are Synthesized in Corynebacterium matruchotii and Mycobacterium smegmatis Cultured in the Presence of Tween 80

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Cindy Wang

2011-01-01

Full Text Available The addition of polyoxyethylene sorbitan monooleate (Tween 80 to a culture of mycobacteria greatly influences cell permeability and sensitivity to antibiotics but very little is known regarding the underlying mechanism. Here we show that Corynebacterium matruchotii (surrogate of mycobacteria converts Tween 80 to a structural series of polyoxyethylenic acids which are then used to form novel series-2A and series-2B glycolipids. Minor series-3 glycolipids were also synthesized. The polyoxyethylenic acids replaced corynomycolic acids in the cell wall. Correspondingly the trehalose dicorynomycolate content was reduced. MALDI mass spectrometry, MS-MS, 1H-NMR, and 13C-NMR were used to characterize the series-2 glycolipids. Series-2A glycolipid is trehalose 6-C36:2-corynomycolate-6′-polyoxyethylenate and series-2B glycolipid is trehalose 6-C36:2-corynomycolate-6′-furan ring-containing polyoxyethylenate. Mycobacterium smegmatis grown in the presence of Tween 80 also synthesizes series-2 type glycolipids. The synthesis of these novel glycolipids in corynebacteria and mycobacteria should result in gross changes in the cell wall permeability and drug sensitivity.

Regulatory T Cells and Pro-inflammatory Responses Predominate in Children with Tuberculosis

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Elizabeth Whittaker

2017-04-01

Full Text Available BackgroundFollowing infection with Mycobacterium tuberculosis (M.tb, children are more susceptible to develop disease particularly extrapulmonary disease than adults. The exact mechanisms required for containment of M.tb are not known, but would be important to identify correlates of protection.ObjectiveTo comprehensively analyze key immune responses to mycobacteria between HIV-negative children with extrapulmonary TB (EPTB compared to children with pulmonary TB (PTB or healthy controls.MethodsWhole blood was stimulated in vitro with mycobacteria for 24 h or 6 days to induce effector and memory responses. CD4, CD8, γδ, regulatory T cells, and their related cytokines were measured. Samples of children with tuberculosis (TB disease were analyzed both at time of diagnosis and at the end of TB treatment to determine if any differences were due to TB disease or an underlying host phenotype.ResultsSeventy-six children with TB disease (48 with PTB and 28 with EPTB and 83 healthy controls were recruited to the study. The frequency of CD4+CD25+CD39+FOXP3+ regulatory T cells and secreted IL10 were significantly higher in children with TB compared to healthy controls. IFNγ-, IL17-, and IL22-producing γδ T cells, IL22-producing CD4+ T cells and secreted pro-inflammatory cytokines (IFNγ, IL1β, and TNFα were significantly lower in children with TB disease compared to healthy controls. IFNγ-producing CD4+ T cells and Ki67+-proliferating CD4+ T cells, however, were present in equal numbers in both groups. Following treatment, these immune parameters recovered to “healthy” levels or greater in children with PTB, but not those with extrapulmonary TB.ConclusionIn children with TB disease, a predominantly immune regulatory state is present. These immune findings do not distinguish between children with PTB and EPTB at the time of diagnosis. Following treatment, these inflammatory responses recover in PTB, suggesting that the effect is disease

Comparative analysis of Mycobacterium and related Actinomycetes yields insight into the evolution of Mycobacterium tuberculosis pathogenesis.

Science.gov (United States)

McGuire, Abigail Manson; Weiner, Brian; Park, Sang Tae; Wapinski, Ilan; Raman, Sahadevan; Dolganov, Gregory; Peterson, Matthew; Riley, Robert; Zucker, Jeremy; Abeel, Thomas; White, Jared; Sisk, Peter; Stolte, Christian; Koehrsen, Mike; Yamamoto, Robert T; Iacobelli-Martinez, Milena; Kidd, Matthew J; Maer, Andreia M; Schoolnik, Gary K; Regev, Aviv; Galagan, James

2012-03-28

The sequence of the pathogen Mycobacterium tuberculosis (Mtb) strain H37Rv has been available for over a decade, but the biology of the pathogen remains poorly understood. Genome sequences from other Mtb strains and closely related bacteria present an opportunity to apply the power of comparative genomics to understand the evolution of Mtb pathogenesis. We conducted a comparative analysis using 31 genomes from the Tuberculosis Database (TBDB.org), including 8 strains of Mtb and M. bovis, 11 additional Mycobacteria, 4 Corynebacteria, 2 Streptomyces, Rhodococcus jostii RHA1, Nocardia farcinia, Acidothermus cellulolyticus, Rhodobacter sphaeroides, Propionibacterium acnes, and Bifidobacterium longum. Our results highlight the functional importance of lipid metabolism and its regulation, and reveal variation between the evolutionary profiles of genes implicated in saturated and unsaturated fatty acid metabolism. It also suggests that DNA repair and molybdopterin cofactors are important in pathogenic Mycobacteria. By analyzing sequence conservation and gene expression data, we identify nearly 400 conserved noncoding regions. These include 37 predicted promoter regulatory motifs, of which 14 correspond to previously validated motifs, as well as 50 potential noncoding RNAs, of which we experimentally confirm the expression of four. Our analysis of protein evolution highlights gene families that are associated with the adaptation of environmental Mycobacteria to obligate pathogenesis. These families include fatty acid metabolism, DNA repair, and molybdopterin biosynthesis. Our analysis reinforces recent findings suggesting that small noncoding RNAs are more common in Mycobacteria than previously expected. Our data provide a foundation for understanding the genome and biology of Mtb in a comparative context, and are available online and through TBDB.org.

Detection and identification of globally distributed mycobacterial fish pathogens in some ornamental fish in India.

Science.gov (United States)

Shukla, Shubhra; Sharma, Rolee; Shukla, Sanjeev Kumar

2013-09-01

Mycobacteriosis is a progressive disease of a wide range of wild and captive, marine and freshwater fish species. Conventional detection of fish Mycobacteria is based on histopathology, culture, and biochemical characteristics. The present study analyzed the occurrence of Mycobacteria in clinically ill ornamental fish of different species, from different places of India. In first group, 60 fish were examined for presence of granulomatous inflammation and acid-fast bacteria. Thirty-eight (63.34 %) fish were positive for granulomatous inflammations. Presences of acid-fast bacteria were detected in 27 (45 %) fish having granulomatous inflammation and in two (3.33 %) fish without granulomatous inflammation. In total, AFB were found in 29 (48.34 %) of the 60 fish examined. In second group, 20 fish having granulomatous inflammation, 12 (60 %) samples were positive using Ziehl-Neelsen (Z-N) staining and 11 (55 %) of them were culture positive. Eight (40 %) samples were Z-N negative but two (10 %) of them were culture positive. In total, 13 (65 %) of the 20 examined fish were culture positive. On the basis of biochemical tests and 16S rRNA sequencing, 13 isolates were identified: five as Mycobacterium fortuitum, five as Mycobacterium gordonae, and three as Mycobacterium chelonae. In comparison of two decontamination methods, 2 % HCl treatment was better than 4 % NaOH treatment. Mycobacteria recovery from decontaminated samples was significantly high on Lowenstein-Jensen medium compared to Middlebrook 7H11 agar and Stonebrink (SB) media. The disease is transmissible from fish to fish and also from fish to human, so the significance of Mycobacteria in ornamental fish should not be overlooked.

Microstructure and Textural Properties of Yoghurts Produced by Exopolysaccharides- Producing Starter Cultures

DEFF Research Database (Denmark)

Zhang, Lanjun

conferred a ropy texture and resulted in yoghurts with decreased water holding capacity and an open microstructure. In addition, one of the LB strains with high amounts of EPS producing capacity improved water retention, when it was combined with an ST strain that produced negligible amounts of EPS...

Producers give prices a boost

International Nuclear Information System (INIS)

Anon.

1992-01-01

Uranium producers came alive in August, helping spot prices crack the $8.00 barrier for the first time since March. The upper end of NUKEM's price range actually finished the month at $8.20. Scrambling to fulfill their long-term delivery contracts, producers dominate the market. In the span of three weeks, five producers came out for 2 million lbs U3O8, ultimately buying nearly 1.5 million lbs. One producer accounted for over half this volume. The major factor behind rising prices was that producers required specific origins to meet contract obligations. Buyers willing to accept open origins created the lower end of NUKEM's price range

Producing the Spielberg Brand

OpenAIRE

Russell, J.

2016-01-01

This chapter looks at the manufacture of Spielberg’s brand, and the limits of its usage. Spielberg’s directorial work is well known, but Spielberg’s identity has also been established in other ways, and I focus particularly on his work as a producer. At the time of writing, Spielberg had produced (or executive produced) 148 movies and television series across a range of genres that takes in high budget blockbusters and low budget documentaries, with many more to come. In these texts, Spielber...

Successfully treated Mycobacterium abscessus mastitis: A rare cause of breast masses

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K K Yasar

2011-01-01

Full Text Available Rapidly growing mycobacteria are pathogens responsible for cutaneous or subcutaneous infections especially occurring after injection, trauma or surgery. We describe a patient with Mycobacterium abscessus mastitis that presented as a mass lesion and haemorrhagical discharge. It was initially diagnosed and treated as fibrocystic disease and non-specific abscess. Full recovery was obtained with combination therapy of clarithromycin, linezolid and amikacin without surgical debridement followed by several abscess aspirations. Atypical mycobacteria should be considered in diagnosis of chronic breast lesions in endemic areas. This is the first reported case of mastitis due to M. abscessus in Turkey.

Co-incubation with IL-18 potentiates antigen-specific IFN-γ response in a whole-blood stimulation assay for measurement of cell-mediated immune responses in pigs experimentally infected with Lawsonia intracellularis

DEFF Research Database (Denmark)

Riber, Ulla; Boesen, Henriette Toft; Jakobsen, Jeanne Toft

2011-01-01

The whole-blood interferon-gamma (IFN-γ) assay is a quantitative in-vitro assay for a direct read out of Ag-specific cell-mediated immune (CMI) responses to infectious diseases. The IFN-γ assay is robust in severe intracellular infections like Brucella or mycobacteria, but more difficult to evalu......The whole-blood interferon-gamma (IFN-γ) assay is a quantitative in-vitro assay for a direct read out of Ag-specific cell-mediated immune (CMI) responses to infectious diseases. The IFN-γ assay is robust in severe intracellular infections like Brucella or mycobacteria, but more difficult...

Polysaccharide-producing microalgae

Energy Technology Data Exchange (ETDEWEB)

Braud, J.P.; Chaumont, D.; Gudin, C.; Thepenier, C.; Chassin, P.; Lemaire, C.

1982-11-01

The production of extracellular polysaccharides is studied with Nostoc sp (cyanophycus), Porphiridium cruentum, Rhodosorus marinus, Rhodella maculata (rhodophyci) and Chlamydomonas mexicana (chlorophycus). The polysaccharides produced are separated by centrifugation of the culture then precipitation with alcohol. Their chemical structure was studied by infrared spectrometry and acid hydrolysis. By their rheological properties and especially their insensitivity to temperatrure and pH variations the polysaccharides produced by Porphryridium cruentum and Rhodella maculata appear as suitable candidates for industrial applications.

Adaptive evolution of drug targets in producer and non-producer organisms

DEFF Research Database (Denmark)

Hansen, Bjarne Gram; Sun, Xin E.; Genee, Hans Jasper

2012-01-01

MPA (mycophenolic acid) is an immunosuppressive drug produced by several fungi in Penicillium subgenus Penicillium. This toxic metabolite is an inhibitor of IMPDH (IMP dehydrogenase). The MPA-biosynthetic cluster of Penicillum brevicompactum contains a gene encoding a B-type IMPDH, IMPDH-B, which...... confers MPA resistance. Surprisingly, all members of the subgenus Penicillium contain genes encoding IMPDHs of both the A and B types, regardless of their ability to produce MPA. Duplication of the IMPDH gene occurred before and independently of the acquisition of the MPAbiosynthetic cluster. Both P....... brevicompactum IMPDHs are MPA-resistant, whereas the IMPDHs from a non-producer are MPA-sensitive. Resistance comes with a catalytic cost: whereas P. brevicompactum IMPDH-B is >1000-fold more resistant to MPA than a typical eukaryotic IMPDH, its value of kcat/Km is 0.5%of ‘normal’. Curiously, IMPDH...

Atypical mycobacterias associated to acupuncuture: an integrative review Micobacterias atípicas asociadas a la acupuntura: revisión integral Micobactérias atípicas associadas à acupuntura: revisão integrativa

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Juliana Rizzo Gnatta

2013-02-01

Full Text Available AIM: to evaluate evidence concerning sources or mechanisms of infection transmission of atypical mycobacteria associated with acupuncture, and the species causing infections. METHOD: research was performed in December 2011 in the databases of LILACS, MEDLINE, EMBASE, OvidSP and the Cochrane Library, without restrictions regarding publication date, study type or language. RESULTS: of the 16 publications, only one identified the contamination source: diluted glutaraldehyde solution used to clean equipment. Three established likely sources: towels, hot packs or boiling tank water, and the reuse of reprocessed needles. Four indicated possible sources: contaminated needles, reuse of personal needles, patient's skin colonized by mycobacteria and reuse of needles at different sites in the same patient. Eight of the studies did not mention the sources. CONCLUSION: among 295 cases, M. abscessus was the pathological agent in over 96%. Well-established control practices for infection prevention should be implemented and adapted for complementary and alternative medicine.OBJETIVO: evaluar la evidencia existente sobre las principales fuentes o mecanismos de transmisión de la infección por micobacterias atípicas asociadas con la acupuntura, y las especies causantes de infecciones. MÉTODO: investigación que llevó a cabo en Diciembre de 2011 con descriptores indexados en las bases de datos LILACS, MEDLINE, EMBASE, OvidSP y la Biblioteca Cochrane, sin restricciones en cuanto a la fecha de publicación, tipo de estudio o de idioma. RESULTADOS: de las 16 publicaciones, sólo una identificó la fuente de contaminación: la solución de glutaraldehído diluido utilizada para limpiar el equipo. Tres publicaciones establecieron como fuentes probables: las toallas, compresas calientes o el agua hervida, y la reutilización de las agujas reprocesadas. Cuatro publicaciones indicaron como fuentes posibles: las agujas contaminadas, la reutilización de agujas

Producers and oil markets

International Nuclear Information System (INIS)

Greaves, W.

1993-01-01

This article attempts an assessment of the potential use of futures by the Middle East oil producers. It focuses on Saudi Arabia since the sheer size of Saudi Arabian sales poses problems, but the basic issues discussed are similar for the other Middle East producers. (Author)

Mycobacteria, Metals, and the Macrophage

Science.gov (United States)

Niederweis, Michael; Wolschendorf, Frank; Mitra, Avishek; Neyrolles, Olivier

2015-01-01

Summary Mycobacterium tuberculosis is a facultative intracellular pathogen that thrives inside host macrophages. A key trait of M. tuberculosis is to exploit and manipulate metal cation trafficking inside infected macrophages to ensure survival and replication inside the phagosome. Here we describe the recent fascinating discoveries that the mammalian immune system responds to infections with M. tuberculosis by overloading the phagosome with copper and zinc, two metals which are essential nutrients in small quantities but are toxic in excess. M. tuberculosis has developed multi-faceted resistance mechanisms to protect itself from metal toxicity including control of uptake, sequestration inside the cell, oxidation, and efflux. The host response to infections combines this metal poisoning strategy with nutritional immunity mechanisms that deprive M. tuberculosis from metals such as iron and manganese to prevent bacterial replication. Both immune mechanisms rely on the translocation of metal transporter proteins to the phagosomal membrane during the maturation process of the phagosome. This review summarizes these recent findings and discusses how metal-targeted approaches might complement existing TB chemotherapeutic regimens with novel anti-infective therapies. PMID:25703564

Learning epigenetic regulation from mycobacteria

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Sanjeev Khosla

2016-01-01

Full Text Available In a eukaryotic cell, the transcriptional fate of a gene is determined by the profile of the epigenetic modifications it is associated with and the conformation it adopts within the chromatin. Therefore, the function that a cell performs is dictated by the sum total of the chromatin organization and the associated epigenetic modifications of each individual gene in the genome (epigenome. As the function of a cell during development and differentiation is determined by its microenvironment, any factor that can alter this microenvironment should be able to alter the epigenome of a cell. In the study published in Nature Communications (Yaseen [2015] Nature Communications 6:8922 doi: 10.1038/ncomms9922, we show that pathogenic Mycobacterium tuberculosis has evolved strategies to exploit this pliability of the host epigenome for its own survival. We describe the identification of a methyltransferase from M. tuberculosis that functions to modulate the host epigenome by methylating a novel, non-canonical arginine, H3R42 in histone H3. In another study, we showed that the mycobacterial protein Rv2966c methylates cytosines present in non-CpG context within host genomic DNA upon infection. Proteins with ability to directly methylate host histones H3 at a novel lysine residue (H3K14 has also been identified from Legionella pnemophilia (RomA. All these studies indicate the use of non-canonical epigenetic mechanisms by pathogenic bacteria to hijack the host transcriptional machinery.

Pneumothorax associated with nontuberculous mycobacteria

Science.gov (United States)

Ueyama, M; Asakura, Takanori; Morimoto, Kozo; Namkoong, Ho; Matsuda, Shuichi; Osawa, Takeshi; Ishii, Makoto; Hasegawa, Naoki; Kurashima, Atsuyuki; Goto, Hajime

2016-01-01

Abstract The incidence of nontuberculous mycobacterial pulmonary disease (NTMPD) is increasing worldwide. Secondary spontaneous pneumothorax occurs as a complication of underlying lung disease and is associated with higher morbidity, mortality, and recurrence than primary spontaneous pneumothorax. We here investigated the clinical features and long-term outcomes of pneumothorax associated with NTMPD. We conducted a retrospective study on consecutive adult patients with pneumothorax associated with NTMPD at Fukujuji Hospital and Keio University Hospital from January 1992 to December 2013. We reviewed the medical records of 69 such patients to obtain clinical characteristics, radiological findings, and long-term outcomes, including pneumothorax recurrence and mortality. The median age of the patients was 68 years; 34 patients were women. The median body mass index was 16.8 kg/m2. Underlying pulmonary diseases mainly included chronic obstructive pulmonary disease and pulmonary tuberculosis. On computed tomography, nodules and bronchiectasis were observed in 46 (98%) and 45 (96%) patients, respectively. Consolidation, pleural thickening, interlobular septal thickening, and cavities were most common, and observed in 40 (85%), 40 (85%), 37 (79%), and 36 (77%) patients, respectively. Regarding pneumothorax treatment outcomes, complete and incomplete lung expansion were observed in 49 patients (71%) and 15 patients (22%), respectively. The survival rate after pneumothorax was 48% at 5 years. By the end of the follow-up, 33 patients had died, and the median survival was 4.4 years with a median follow-up period of 1.7 years. The rate of absence of recurrence after the first pneumothorax was 59% at 3 years. By the end of the follow-up, 18 patients had experienced pneumothorax recurrence. Furthermore, 12/18 patients (66%) with recurrent pneumothorax died during the study period. Twenty-three patients (70%) died because of NTMPD progression. Low body mass index (BMI) was a negative prognostic factor for pneumothorax associated with NTMPD in multivariate analysis (HR 0.79, 95% CI 0.64−0.96; P = 0.018) Patients with pneumothorax associated with NTMPD have advanced disease, a high rate of pneumothorax recurrence, and poor prognosis, regardless of the pneumothorax treatment used. Further improvements in early diagnosis of NTMPD and appropriate management in both NTMPD and NTMPD-associated pneumothorax are needed. PMID:27442650

[Distiller Yeasts Producing Antibacterial Peptides].

Science.gov (United States)

Klyachko, E V; Morozkina, E V; Zaitchik, B Ts; Benevolensky, S V

2015-01-01

A new method of controlling lactic acid bacteria contamination was developed with the use of recombinant Saccharomyces cerevisiae strains producing antibacterial peptides. Genes encoding the antibacterial peptides pediocin and plantaricin with codons preferable for S. cerevisiae were synthesized, and a system was constructed for their secretory expression. Recombinant S. cerevisiae strains producing antibacterial peptides effectively inhibit the growth of Lactobacillus sakei, Pediacoccus pentasaceus, Pediacoccus acidilactici, etc. The application of distiller yeasts producing antibacterial peptides enhances the ethanol yield in cases of bacterial contamination. Recombinant yeasts producing the antibacterial peptides pediocin and plantaricin can successfully substitute the available industrial yeast strains upon ethanol production.

Mycobacterial RNA isolation optimized for non-coding RNA: high fidelity isolation of 5S rRNA from Mycobacterium bovis BCG reveals novel post-transcriptional processing and a complete spectrum of modified ribonucleosides.

Science.gov (United States)

Hia, Fabian; Chionh, Yok Hian; Pang, Yan Ling Joy; DeMott, Michael S; McBee, Megan E; Dedon, Peter C

2015-03-11

A major challenge in the study of mycobacterial RNA biology is the lack of a comprehensive RNA isolation method that overcomes the unusual cell wall to faithfully yield the full spectrum of non-coding RNA (ncRNA) species. Here, we describe a simple and robust procedure optimized for the isolation of total ncRNA, including 5S, 16S and 23S ribosomal RNA (rRNA) and tRNA, from mycobacteria, using Mycobacterium bovis BCG to illustrate the method. Based on a combination of mechanical disruption and liquid and solid-phase technologies, the method produces all major species of ncRNA in high yield and with high integrity, enabling direct chemical and sequence analysis of the ncRNA species. The reproducibility of the method with BCG was evident in bioanalyzer electrophoretic analysis of isolated RNA, which revealed quantitatively significant differences in the ncRNA profiles of exponentially growing and non-replicating hypoxic bacilli. The method also overcame an historical inconsistency in 5S rRNA isolation, with direct sequencing revealing a novel post-transcriptional processing of 5S rRNA to its functional form and with chemical analysis revealing seven post-transcriptional ribonucleoside modifications in the 5S rRNA. This optimized RNA isolation procedure thus provides a means to more rigorously explore the biology of ncRNA species in mycobacteria. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

NOD2, RIP2 and IRF5 Play a Critical Role in the Type I Interferon Response to Mycobacterium tuberculosis

Science.gov (United States)

Jiang, Zhaozhao; Fortune, Sarah M.; Coulombe, Francois; Behr, Marcel A.; Fitzgerald, Katherine A.; Sassetti, Christopher M.; Kelliher, Michelle A.

2009-01-01

While the recognition of microbial infection often occurs at the cell surface via Toll-like receptors, the cytosol of the cell is also under surveillance for microbial products that breach the cell membrane. An important outcome of cytosolic recognition is the induction of IFNα and IFNβ, which are critical mediators of immunity against both bacteria and viruses. Like many intracellular pathogens, a significant fraction of the transcriptional response to Mycobacterium tuberculosis infection depends on these type I interferons, but the recognition pathways responsible remain elusive. In this work, we demonstrate that intraphagosomal M. tuberculosis stimulates the cytosolic Nod2 pathway that responds to bacterial peptidoglycan, and this event requires membrane damage that is actively inflicted by the bacterium. Unexpectedly, this recognition triggers the expression of type I interferons in a Tbk1- and Irf5-dependent manner. This response is only partially impaired by the loss of Irf3 and therefore, differs fundamentally from those stimulated by bacterial DNA, which depend entirely on this transcription factor. This difference appears to result from the unusual peptidoglycan produced by mycobacteria, which we show is a uniquely potent agonist of the Nod2/Rip2/Irf5 pathway. Thus, the Nod2 system is specialized to recognize bacteria that actively perturb host membranes and is remarkably sensitive to mycobacteria, perhaps reflecting the strong evolutionary pressure exerted by these pathogens on the mammalian immune system. PMID:19578435

Comparative analysis of mycobacterium and related actinomycetes yields insight into the evolution of mycobacterium tuberculosis pathogenesis

Directory of Open Access Journals (Sweden)

McGuire Abigail

2012-03-01

Full Text Available Abstract Background The sequence of the pathogen Mycobacterium tuberculosis (Mtb strain H37Rv has been available for over a decade, but the biology of the pathogen remains poorly understood. Genome sequences from other Mtb strains and closely related bacteria present an opportunity to apply the power of comparative genomics to understand the evolution of Mtb pathogenesis. We conducted a comparative analysis using 31 genomes from the Tuberculosis Database (TBDB.org, including 8 strains of Mtb and M. bovis, 11 additional Mycobacteria, 4 Corynebacteria, 2 Streptomyces, Rhodococcus jostii RHA1, Nocardia farcinia, Acidothermus cellulolyticus, Rhodobacter sphaeroides, Propionibacterium acnes, and Bifidobacterium longum. Results Our results highlight the functional importance of lipid metabolism and its regulation, and reveal variation between the evolutionary profiles of genes implicated in saturated and unsaturated fatty acid metabolism. It also suggests that DNA repair and molybdopterin cofactors are important in pathogenic Mycobacteria. By analyzing sequence conservation and gene expression data, we identify nearly 400 conserved noncoding regions. These include 37 predicted promoter regulatory motifs, of which 14 correspond to previously validated motifs, as well as 50 potential noncoding RNAs, of which we experimentally confirm the expression of four. Conclusions Our analysis of protein evolution highlights gene families that are associated with the adaptation of environmental Mycobacteria to obligate pathogenesis. These families include fatty acid metabolism, DNA repair, and molybdopterin biosynthesis. Our analysis reinforces recent findings suggesting that small noncoding RNAs are more common in Mycobacteria than previously expected. Our data provide a foundation for understanding the genome and biology of Mtb in a comparative context, and are available online and through TBDB.org.

Rapid presumptive identification of the Mycobacterium tuberculosis-bovis complex by radiometric determination of heat stable urease

International Nuclear Information System (INIS)

Gandy, J.H.; Pruden, E.L.; Cox, F.R.

1983-01-01

Simple and rapid Bactec methodologies for the determination of neat (unaltered) and heat stable urease activity of mycobacteria are presented. Clinical isolates (63) and stock cultures (32)--consisting of: M. tuberculosis (19), M. bovis (5), M. kansasii (15), M. marinum (4), M. simiae (3), M. scrofulaceum (16), M. gordonae (6), M. szulgai (6), M. flavescens (1), M. gastri (1), M. intracellulare (6), M. fortuitum-chelonei complex (12), and M. smegmatis (1)--were tested for neat urease activity by Bactec radiometry. Mycobacterial isolates (50-100 mg wet weight) were incubated at 35 degrees C for 30 minutes with microCi14C-urea. Urease-positive mycobacteria gave Bactec growth index (GI) values greater than 100 units, whereas urease-negative species gave values less than 10 GI units. Eighty-three isolates possessing neat urease activity were heated at 80 degrees C for 30 minutes followed by incubation at 35 degrees C for 30 minutes with 1 microCi14C-urea. Mycobacterium tuberculosis-bovis complex demonstrated heat-stable urease activity (GI more than 130 units) and could be distinguished from mycobacteria other than tuberculosis (MOTT), which gave GI values equal to or less than 40 units

[Detection of Salmonella and Mycobacterium species in seagulls captured in Talcahuano, Chile].

Science.gov (United States)

López-Martín, Juana; Junod, Tania; Riquelme, Fredy; Contreras, Cecilia; González-Acuña, Daniel

2011-11-01

Salmonella can be isolated from the feces of seagulls. Therefore these birds can be a vector for dissemination of this pathogen. To evaluate the possible role of gulls as vectors of two important human and animal pathogens (My-cobacteria and Salmonella). One hundred twenty three Kelp gull (Larus dominicanus) and 60 Franklin gulls (Leucophaeus pipixcan) captured off the coast of the seaport of Talcahuano, were analyzed. Using traditional microbiological methods, the presence of Mycobacteria in cloacal swabs and feet lavages, was analyzed in both types of gulls. To detect the presence of Salmonella, feces, fecal and tracheal swabs, and feet lavage were analyzed from Franklin gulls. Feces, feet lavage, intestine, spleen, liver, kidney and lung, were examined in Kelp gulls. All Mycobacteria cultures were negative. Salmonella enterica cultures were positive in 25 % of Kelp gulls and 6.7 % of Franklin gulls. Four serovars were identified by serotyping. Enteritidis and Senfteberg serovars were found in both types of gulls. Anatum and Infantis serovars were found only in Kelp gulls. Feces of gulls captured during the winter had the highest yield of positive cultures (36.1%). Seagulls are an important Salmonella vector in Chile.

DETECTION OF MYCOBACTERIUM TUBERCULOSIS IN BLOOD FOR DIAGNOSIS OF GENERALISED TUBERCULOSIS IN HIV-POSITIVE PATIENTS

Directory of Open Access Journals (Sweden)

V. N. Zimina

2017-01-01

Full Text Available Objective: To study the informative value of the detection of mycobacteria in blood with the cultural method in patients with suspected tuberculous sepsis and to determine the most significant clinical and laboratory criteria for testing. Materials and methods: The investigation to detect M.tuberculosis was fulfilled in 159 HIV-positive patients with suspected tuberculosis sepsis. Blood culture was completed with culture medium Myco/F Lytic Culture Vials and analyzer BACTEC 9050. Results: Mycobacteria were detected in blood of 19 patients (11,9% of all patients: in 18 patients the growth of М. tuberculosis complex was detected (25,3% of all patients with diagnosed tuberculosis and in 1 patient it was Mycobacterium avium complex (0,6% of all patients. It was shown, that the probability of M.tuberculosis detection was especially associated with the severity of the disease, immunosupression (less than 100 cells/mkl, hemoglobin quantity less than 90 g/l (levels were determined through the seeking for the most significant cutoffs. It was not proofed, that meningoencephalitis develops more often in patients with proven bacteremia. There were no evident differences in detection frequency of mycobacteria in sputum between patients with tuberculous sepsis and without it.

Extracellular Sphingomyelinase Rv0888 of Mycobacterium tuberculosis Contributes to Pathological Lung Injury of Mycobacterium smegmatis in Mice via Inducing Formation of Neutrophil Extracellular Traps.

Science.gov (United States)

Dang, Guanghui; Cui, Yingying; Wang, Lei; Li, Tiantian; Cui, Ziyin; Song, Ningning; Chen, Liping; Pang, Hai; Liu, Siguo

2018-01-01

Mycobacterium tuberculosis is the causative agent of tuberculosis (TB), which mainly causes pulmonary injury and tubercles. Although macrophages are generally considered to harbor the main cells of M. tuberculosis , new evidence suggests that neutrophils are rapidly recruited to the infected lung. M. tuberculosis itself, or its early secreted antigenic target protein 6 (ESAT-6), can induce formation of neutrophil extracellular traps (NETs). However, NETs trap mycobacteria but are unable to kill them. The role of NETs' formation in the pathogenesis of mycobacteria remains unclear. Here, we report a new M. tuberculosis extracellular factor, bifunctional enzyme Rv0888, with both nuclease and sphingomyelinase activities. Rv0888 sphingomyelinase activity can induce NETs' formation in vitro and in the lung of the mice and enhance the colonization ability of Mycobacterium smegmatis in the lungs of mice. Mice infected by M. smegmatis harboring Rv0888 sphingomyelinase induced pathological injury and inflammation of the lung, which was mainly mediated by NETs, induced by Rv0888 sphingomyelinase, associated protein (myeloperoxidase) triggered caspase-3. In summary, the study sheds new light on the pathogenesis of mycobacteria and reveals a novel target for TB treatment.

Granulomatous Lobular Mastitis Associated with Mycobacterium abscessus in South China: A Case Report and Review of the Literature

Directory of Open Access Journals (Sweden)

Ye-sheng Wang

2017-01-01

Full Text Available Mycobacteria, which are known as rapidly growing bacteria, are pathogens that are responsible for cutaneous or subcutaneous infections that especially occur after injection, trauma, or surgery. In this report, we describe a species of Mycobacterium abscessus that was isolated from a breast abscess in a patient who was previously diagnosed with granulomatous lobular mastitis (GLM. This current case is the first ever presented case of GLM associated with M. abscessus documented in South China. The case presentation highlights the role of M. abscessus in GLM. The association of M. abscessus and GLM is discussed and a summary of breast infection due to Mycobacteria is given.

Granulomatous Lobular Mastitis Associated with Mycobacterium abscessus in South China: A Case Report and Review of the Literature.

Science.gov (United States)

Wang, Ye-Sheng; Li, Qi-Wei; Zhou, Lin; Guan, Run-Feng; Zhou, Xiang-Ming; Wu, Ji-Hong; Rao, Nan-Yan; Zhu, Shuang

2017-01-01

Mycobacteria, which are known as rapidly growing bacteria, are pathogens that are responsible for cutaneous or subcutaneous infections that especially occur after injection, trauma, or surgery. In this report, we describe a species of Mycobacterium abscessus that was isolated from a breast abscess in a patient who was previously diagnosed with granulomatous lobular mastitis (GLM). This current case is the first ever presented case of GLM associated with M. abscessus documented in South China. The case presentation highlights the role of M. abscessus in GLM. The association of M. abscessus and GLM is discussed and a summary of breast infection due to Mycobacteria is given.

Human body may produce bacteria.

Science.gov (United States)

Salerian, Alen J

2017-06-01

"Human body may produce bacteria" proposes that human body may produce bacteria and represent an independent source of infections contrary to the current paradigm of infectious disorders proposed by Louis Pasteur in 1880. The following observations are consistent with this hypothesis: A. Bidirectional transformations of both living and nonliving things have been commonly observed in nature. B. Complex multicellular organisms harbor the necessary properties to produce bacteria (water, nitrogen and oxygen). C. Physical laws suggest any previously observed phenomenon or action will occur again (life began on earth; a non living thing). D. Animal muscle cells may generate energy (fermentation). E. Sterilized food products (i.e. boiled eggs), may produce bacteria and fungus under special conditions and without any exposure to foreign living cells. "Human body may produce bacteria" may challenge the current medical paradigm that views human infectious disorders as the exclusive causative byproducts of invading foreign cells. It may also introduce new avenues to treat infectious disorders. Copyright © 2017 Elsevier Ltd. All rights reserved.

Methods of producing transportation fuel

Science.gov (United States)

Nair, Vijay [Katy, TX; Roes, Augustinus Wilhelmus Maria [Houston, TX; Cherrillo, Ralph Anthony [Houston, TX; Bauldreay, Joanna M [Chester, GB

2011-12-27

Systems, methods, and heaters for treating a subsurface formation are described herein. At least one method for producing transportation fuel is described herein. The method for producing transportation fuel may include providing formation fluid having a boiling range distribution between -5.degree. C. and 350.degree. C. from a subsurface in situ heat treatment process to a subsurface treatment facility. A liquid stream may be separated from the formation fluid. The separated liquid stream may be hydrotreated and then distilled to produce a distilled stream having a boiling range distribution between 150.degree. C. and 350.degree. C. The distilled liquid stream may be combined with one or more additives to produce transportation fuel.

Price satisfaction and producer loyalty

DEFF Research Database (Denmark)

Mutonyi, Sarah; Beukel, Karin; Gyau, Amos

2016-01-01

Purpose The purpose of this paper is to investigate which dimensions of price satisfaction influence producers’ trust in buyers and assess the mediating role of such trust in the relationship between price satisfaction and producer loyalty in fresh fruit supply chains. Design/methodology/approach......Purpose The purpose of this paper is to investigate which dimensions of price satisfaction influence producers’ trust in buyers and assess the mediating role of such trust in the relationship between price satisfaction and producer loyalty in fresh fruit supply chains. Design...... reliability, and relative price are dimensions of price satisfaction that affect producers’ trust in the buyer. Moreover, trust between the producer and the buyer is found to be a strong mediator between price satisfaction and producer loyalty. The findings support recent studies about trust and its mediating...... between the multi-dimensional nature of price satisfaction and producer loyalty with trust as a mediating variable in the business-to-business (B2B) context. Although B2B relationships have been shown to be of great importance for smallholders in enhancing business performance with their buyers, little...

Bacteriocin producers from traditional food products

Directory of Open Access Journals (Sweden)

Thonart P.

2007-01-01

Full Text Available A total of 220 strains of LAB isolated from 32 samples of traditional fermented food from Senegal were screened for bacteriocin production. Two bacteriocin producers, Lactococcus lactis subsp. lactis and Enterococcus faecium, were identified from 12 bacteriocin-producing isolates on the basis of phenotypic analyses and 16S rDNA sequence. Both bacteriocins produced by new isolates show antimicrobial activity against Listeria monocytogenes and Bacillus coagulans whereas only that produced by Lactococcus lactis has an activity against Bacillus cereus. Bacteriocin-producing Lactococcus lactis strains were found in a variety of traditional foods indicating a high potential of growth of this strain in variable ecological complex environment. Partial 16S rDNA of the two bacteriocin producers obtained in this study has been registered to Genbank databases under the accession number AY971748 for Lactococcus lactis subsp. lactis (named CWBI-B1410 and AY971749 for Enterococcus faecium (named CWBI-B1411. The new bacteriocin-producing Lactococcus lactis subsp. lactis strain has been selected for identification and application of the bacteriocin to food preservation.

Methods for producing diterpenes

DEFF Research Database (Denmark)

2015-01-01

The present invention discloses that by combining different di TPS enzymes of class I and class II different diterpenes may be produced including diterpenes not identified in nature. Surprisingly it is revealed that a di TPS enzyme of class I of one species may be combined with a di TPS enzyme...... of class II from a different species, resulting in a high diversity of diterpenes, which can be produced....

Process for producing ethanol from syngas

Science.gov (United States)

Krause, Theodore R; Rathke, Jerome W; Chen, Michael J

2013-05-14

The invention provides a method for producing ethanol, the method comprising establishing an atmosphere containing methanol forming catalyst and ethanol forming catalyst; injecting syngas into the atmosphere at a temperature and for a time sufficient to produce methanol; and contacting the produced methanol with additional syngas at a temperature and for a time sufficient to produce ethanol. The invention also provides an integrated system for producing methanol and ethanol from syngas, the system comprising an atmosphere isolated from the ambient environment; a first catalyst to produce methanol from syngas wherein the first catalyst resides in the atmosphere; a second catalyst to product ethanol from methanol and syngas, wherein the second catalyst resides in the atmosphere; a conduit for introducing syngas to the atmosphere; and a device for removing ethanol from the atmosphere. The exothermicity of the method and system obviates the need for input of additional heat from outside the atmosphere.

Phage transposon mutagenesis.

Science.gov (United States)

Siegrist, M Sloan; Rubin, Eric J

2009-01-01

Phage transduction is an attractive method of genetic manipulation in mycobacteria. PhiMycoMarT7 is well suited for transposon mutagenesis as it is temperature sensitive for replication and contains T7 promoters that promote transcription, a highly active transposase gene, and an Escherichia coli oriR6 K origin of replication. Mycobacterial transposon mutant libraries produced by PhiMycoMarT7 transduction are amenable to both forward and reverse genetic studies. In this protocol, we detail the preparation of PhiMycoMarT7, including a description of the phage, reconstitution of the phage, purification of plaques, preparation of phage stock, and titering of phage stock. We then describe the transduction procedure and finally outline the isolation of individual transposon mutants.

7 CFR 1212.19 - Producer.

Science.gov (United States)

2010-01-01

... producing, or causing to be produced, honey beyond personal use and having value at first point of sale. ... person who is engaged in the production and sale of honey in any State and who owns, or shares the...

Consumer's Fresh Produce Food Safety Practices: Outcomes of a Fresh Produce Safety Education Program

Science.gov (United States)

Scott, Amanda R.; Pope, Paul E.; Thompson, Britta M.

2009-01-01

The Centers for Disease Control and Prevention estimate that there are 76 million cases of foodborne disease annually. Foodborne disease is usually associated with beef, poultry, and seafood. However, there is an increasing number of foodborne disease cases related to fresh produce. Consumers may not associate fresh produce with foodborne disease…

Mycobacteriophages as versatile tools for genetic manipulation of mycobacteria and development of simple methods for diagnosis of mycobacterial diseases Micobacteriófagos como herramientas versátiles para la manipulación genética y el desarrollo de métodos simples para el diagnóstico de enfermedades micobacterianas

Directory of Open Access Journals (Sweden)

E. J. Stella

2009-03-01

Full Text Available Tuberculosis, caused by Mycobacterium tuberculosis, is responsible for over two million deaths per year worldwide. Due to its long doubling time (18 h, the microbiological detection of M. tuberculosis by conventional methods takes up to one month, unless the number of bacilli in the biological sample is high enough. Thus, drug resistance assessment requires at least one month for obtaining the primary culture and another month to determine its susceptibility to antimycobacterial drugs. Moreover, for a long time, the lack of genetic tools for mycobacteria has been a barrier for undertaking studies aimed at understanding the mechanisms of drug resistance and drug target identification, being all these topics of utmost importance considering the increase in the number of drug-resistant clones and the few therapeutic options available. Mycobacteriophages are promising as a novel source of genetic elements for mycobacteria manipulation, as well as for the development of versatile, simple, fast and cheap methods for drug resistance assessment of M. tuberculosis clinical isolates. We herein describe the background related to the use of mycobacteriophages, with emphasis placed on their utilization for drug resistance analysis in our country.La tuberculosis, enfermedad causada por el bacilo Mycobacterium tuberculosis, es responsable de más de dos millones de muertes anuales en el mundo. Debido a su largo tiempo de duplicación (18 h, la detección bacteriológica de M. tuberculosis por métodos convencionales necesita de un mes o aun más, a menos que el número de bacilos en la muestra clínica sea suficientemente alto. Por consiguiente, se necesita un mínimo de dos meses para determinar la resistencia de este microorganismo a las drogas antituberculosas: uno para obtener el cultivo primario y otro para ensayar la sensibilidad frente a aquellas. La falta de herramientas para la manipulación genética de micobacterias ha dificultado la identificaci

Comparative Proteomics Identifies Host Immune System Proteins Affected by Infection with Mycobacterium bovis.

Directory of Open Access Journals (Sweden)

Vladimir López

2016-03-01

Full Text Available Mycobacteria of the Mycobacterium tuberculosis complex (MTBC greatly impact human and animal health worldwide. The mycobacterial life cycle is complex, and the mechanisms resulting in pathogen infection and survival in host cells are not fully understood. Eurasian wild boar (Sus scrofa are natural reservoir hosts for MTBC and a model for mycobacterial infection and tuberculosis (TB. In the wild boar TB model, mycobacterial infection affects the expression of innate and adaptive immune response genes in mandibular lymph nodes and oropharyngeal tonsils, and biomarkers have been proposed as correlates with resistance to natural infection. However, the mechanisms used by mycobacteria to manipulate host immune response are not fully characterized. Our hypothesis is that the immune system proteins under-represented in infected animals, when compared to uninfected controls, are used by mycobacteria to guarantee pathogen infection and transmission. To address this hypothesis, a comparative proteomics approach was used to compare host response between uninfected (TB- and M. bovis-infected young (TB+ and adult animals with different infection status [TB lesions localized in the head (TB+ or affecting multiple organs (TB++]. The results identified host immune system proteins that play an important role in host response to mycobacteria. Calcium binding protein A9, Heme peroxidase, Lactotransferrin, Cathelicidin and Peptidoglycan-recognition protein were under-represented in TB+ animals when compared to uninfected TB- controls, but protein levels were higher as infection progressed in TB++ animals when compared to TB- and/or TB+ adult wild boar. MHCI was the only protein over-represented in TB+ adult wild boar when compared to uninfected TB- controls. The results reported here suggest that M. bovis manipulates host immune response by reducing the production of immune system proteins. However, as infection progresses, wild boar immune response recovers to

Comparative Proteomics Identifies Host Immune System Proteins Affected by Infection with Mycobacterium bovis.

Science.gov (United States)

López, Vladimir; Villar, Margarita; Queirós, João; Vicente, Joaquín; Mateos-Hernández, Lourdes; Díez-Delgado, Iratxe; Contreras, Marinela; Alves, Paulo C; Alberdi, Pilar; Gortázar, Christian; de la Fuente, José

2016-03-01

Mycobacteria of the Mycobacterium tuberculosis complex (MTBC) greatly impact human and animal health worldwide. The mycobacterial life cycle is complex, and the mechanisms resulting in pathogen infection and survival in host cells are not fully understood. Eurasian wild boar (Sus scrofa) are natural reservoir hosts for MTBC and a model for mycobacterial infection and tuberculosis (TB). In the wild boar TB model, mycobacterial infection affects the expression of innate and adaptive immune response genes in mandibular lymph nodes and oropharyngeal tonsils, and biomarkers have been proposed as correlates with resistance to natural infection. However, the mechanisms used by mycobacteria to manipulate host immune response are not fully characterized. Our hypothesis is that the immune system proteins under-represented in infected animals, when compared to uninfected controls, are used by mycobacteria to guarantee pathogen infection and transmission. To address this hypothesis, a comparative proteomics approach was used to compare host response between uninfected (TB-) and M. bovis-infected young (TB+) and adult animals with different infection status [TB lesions localized in the head (TB+) or affecting multiple organs (TB++)]. The results identified host immune system proteins that play an important role in host response to mycobacteria. Calcium binding protein A9, Heme peroxidase, Lactotransferrin, Cathelicidin and Peptidoglycan-recognition protein were under-represented in TB+ animals when compared to uninfected TB- controls, but protein levels were higher as infection progressed in TB++ animals when compared to TB- and/or TB+ adult wild boar. MHCI was the only protein over-represented in TB+ adult wild boar when compared to uninfected TB- controls. The results reported here suggest that M. bovis manipulates host immune response by reducing the production of immune system proteins. However, as infection progresses, wild boar immune response recovers to limit pathogen

Cellulase producing microorganism ATCC 55702

Science.gov (United States)

Dees, H. Craig

1997-01-01

Bacteria which produce large amounts of cellulase--containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualifies for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques.

Methods of producing cesium-131

Science.gov (United States)

Meikrantz, David H; Snyder, John R

2012-09-18

Methods of producing cesium-131. The method comprises dissolving at least one non-irradiated barium source in water or a nitric acid solution to produce a barium target solution. The barium target solution is irradiated with neutron radiation to produce cesium-131, which is removed from the barium target solution. The cesium-131 is complexed with a calixarene compound to separate the cesium-131 from the barium target solution. A liquid:liquid extraction device or extraction column is used to separate the cesium-131 from the barium target solution.

Agricultural Producer Certificates

Data.gov (United States)

Montgomery County of Maryland — A Certified Agricultural Producer, or representative thereof, is an individual who wishes to sell regionally-grown products in the public right-of-way. A Certified...

29 CFR 780.213 - Produce business.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Produce business. 780.213 Section 780.213 Labor Regulations... Specific Situations Hatchery Operations § 780.213 Produce business. In some instances, hatcheries also engage in the produce business as such and commingle with the culled eggs and chickens other eggs and...

A method of producing hydroxymethyfurfural

DEFF Research Database (Denmark)

2011-01-01

The present invention relates to a method of producing 5-hydroxymethylfurfural by dehydration of fructose and/or glucose and/or mannose.......The present invention relates to a method of producing 5-hydroxymethylfurfural by dehydration of fructose and/or glucose and/or mannose....

Outbreak of persistent cutaneous abscesses due to Mycobacterium chelonae after mesotherapy sessions, Lima, Peru.

Science.gov (United States)

Munayco, César V; Grijalva, Carlos G; Culqui, Dante R; Bolarte, José L; Suárez-Ognio, Luis A; Quispe, Neyda; Calderon, Roger; Ascencios, Luis; Del Solar, Manuel; Salomón, Martín; Bravo, Francisco; Gotuzzo, Eduardo

2008-02-01

Outbreaks of rapidly growing mycobacteria have been occasionally described. The article reports an outbreak of cutaneous abscesses due to Mycobacterium chelonae following mesotherapy in Lima, Peru. From December 2004 through January 2005, 35 subjects who had participated in mesotherapy training sessions presented with persistent cutaneous abscesses. Thirteen (37%) of these suspected cases consented to undergo clinical examination. Skin punch-biopsies were collected from suspicious lesions and substances injected during mesotherapy were analyzed. Suspected cases were mainly young women and lesions included subcutaneous nodules, abscesses and ulcers. Mycobacterium chelonae was isolated from four patients and from a procaine vial. In conclusion, it is important to consider mesotherapy as a potential source of rapidly growing mycobacteria infections.

Imaging features of mycobacterium in patients with acquired immunodeficiency syndrome

International Nuclear Information System (INIS)

Yang Jun; Sun Yue; Wei Liangui; Xu Yunliang; Li Xingwang

2013-01-01

Objective: To analyze the imaging features of mycobacterium in AIDS patients. Methods: Twenty-three cases of mycobacterium tuberculosis and 13 patients of non-tuberculous mycobacteria were proved etiologically and included in this study. All patients underwent X-ray and CT examinations, imaging data were analyzed and compared. Results: The imaging findings of mycobacterium tuberculosis in AIDS patients included consolidation (n = 11), pleural effusion (n = 11), mediastinal lymphadenopathy (n = 11). Pulmonary lesions were always diffuse distribution, and 14 patients of extrapulmonary tuberculosis were found. Pulmonary lesions in non-tuberculous mycobacteria tend to be circumscribed. Conclusions: Non-tuberculous mycobacterial infection in AIDS patients is more common and usually combined with other infections. Imaging features are atypical. (authors)

7 CFR 1033.13 - Producer milk.

Science.gov (United States)

2010-01-01

... Handling Definitions § 1033.13 Producer milk. Producer milk means the skim milk (or the skim equivalent of components of skim milk), including nonfat components, and butterfat in milk of a producer that is: (a... percentages in paragraph (d)(4) of this section may be increased or decreased by the market administrator if...

7 CFR 1001.13 - Producer milk.

Science.gov (United States)

2010-01-01

... Handling Definitions § 1001.13 Producer milk. Producer milk means the skim milk (or the skim equivalent of components of skim milk) and butterfat contained in milk of a producer that is: (a) Received by the operator... be increased or decreased by the Market Administrator if the Market Administrator finds that such...

7 CFR 1126.13 - Producer milk.

Science.gov (United States)

2010-01-01

... Handling Definitions § 1126.13 Producer milk. Producer milk means the skim milk (or the skim equivalent of components of skim milk), including nonfat components, and butterfat contained in milk of a producer that is...) of this section may be increased or decreased by the market administrator if there is a finding that...

Producers' Complex Risk Management Choices

NARCIS (Netherlands)

Pennings, J.M.E.; Isengildina, O.; Irwin, S.H.; Garcia, P.; Good, D.L.

2008-01-01

Producers have a wide variety of risk management instruments available, making their choice(s) complex. The way producers deal with this complexity can vary and may influence the impact that the determinants, such as risk aversion, have on their choices. A recently developed choice bracketing

Producing colour pictures from SCAN

International Nuclear Information System (INIS)

Robichaud, K.

1982-01-01

The computer code SCAN.TSK has been written for use on the Interdata 7/32 minicomputer which will convert the pictures produced by the SCAN program into colour pictures on a colour graphics VDU. These colour pictures are a more powerful aid to detecting errors in the MONK input data than the normal lineprinter pictures. This report is intended as a user manual for using the program on the Interdata 7/32, and describes the method used to produce the pictures and gives examples of JCL, input data and of the pictures that can be produced. (U.K.)

Producing new radionuclides for medicine

International Nuclear Information System (INIS)

Michaut, C.

2009-01-01

The Arronax cyclotron, a new particle accelerator dedicated to the production of radionuclides for medicine and research has been commissioned in Nantes (France). Because of its unique features: an energy of 70 MeV and an intensity of 750 μA, Arronax will produce radionuclides that can not be produce in present cyclotrons. Among others it will produce Strontium-82 and Germanium-68 that are the precursors for Rubidium-82 and Gallium-68 respectively. 20 per cent of the research works will be dedicated to other domains like radioactive wastes, the radiation biological damage and the radiation damage on electronic devices. (A.C.)

7 CFR 1006.13 - Producer milk.

Science.gov (United States)

2010-01-01

... Handling Definitions § 1006.13 Producer milk. Producer milk means the skim milk (or the skim equivalent of components of skim milk) and butterfat contained in milk of a producer that is: (a) Received by the operator... (d) (1) through (3) of this section may be increased or decreased by the market administrator if the...

7 CFR 1205.319 - Cotton-producing region.

Science.gov (United States)

2010-01-01

... 7 Agriculture 10 2010-01-01 2010-01-01 false Cotton-producing region. 1205.319 Section 1205.319... Cotton Research and Promotion Order Definitions § 1205.319 Cotton-producing region. Cotton-producing region means each of the following groups of cotton-producing States: (a) Southeast Region: Alabama...

The draft genome of Mycobacterium aurum, a potential model organism for investigating drugs against Mycobacterium tuberculosis and Mycobacterium leprae

KAUST Repository

Phelan, Jody; Maitra, Arundhati; McNerney, Ruth; Nair, Mridul; Gupta, Antima; Coll, Francesc; Pain, Arnab; Bhakta, Sanjib; Clark, Taane G.

2015-01-01

Mycobacterium aurum (M. aurum) is an environmental mycobacteria that has previously been used in studies of anti-mycobacterial drugs due to its fast growth rate and low pathogenicity. The M. aurum genome has been sequenced and assembled into 46 contigs, with a total length of 6.02 Mb containing 5684 annotated protein-coding genes. A phylogenetic analysis using whole genome alignments positioned M. aurum close to Mycobacterium vaccae and Mycobacterium vanbaalenii, within a clade related to fast-growing mycobacteria. Large-scale genomic rearrangements were identified by comparing the M. aurum genome to those of Mycobacterium tuberculosis and Mycobacterium leprae. M. aurum orthologous genes implicated in resistance to anti-tuberculosis drugs in M. tuberculosis were observed. The sequence identity at the DNA level varied from 68.6% for pncA (pyrazinamide drug-related) to 96.2% for rrs (streptomycin, capreomycin). We observed two homologous genes encoding the catalase-peroxidase enzyme (katG) that is associated with resistance to isoniazid. Similarly, two embB homologues were identified in the M. aurum genome. In addition to describing for the first time the genome of M. aurum, this work provides a resource to aid the use of M. aurum in studies to develop improved drugs for the pathogenic mycobacteria M. tuberculosis and M. leprae.

The draft genome of Mycobacterium aurum, a potential model organism for investigating drugs against Mycobacterium tuberculosis and Mycobacterium leprae

KAUST Repository

Phelan, Jody

2015-06-04

Mycobacterium aurum (M. aurum) is an environmental mycobacteria that has previously been used in studies of anti-mycobacterial drugs due to its fast growth rate and low pathogenicity. The M. aurum genome has been sequenced and assembled into 46 contigs, with a total length of 6.02 Mb containing 5684 annotated protein-coding genes. A phylogenetic analysis using whole genome alignments positioned M. aurum close to Mycobacterium vaccae and Mycobacterium vanbaalenii, within a clade related to fast-growing mycobacteria. Large-scale genomic rearrangements were identified by comparing the M. aurum genome to those of Mycobacterium tuberculosis and Mycobacterium leprae. M. aurum orthologous genes implicated in resistance to anti-tuberculosis drugs in M. tuberculosis were observed. The sequence identity at the DNA level varied from 68.6% for pncA (pyrazinamide drug-related) to 96.2% for rrs (streptomycin, capreomycin). We observed two homologous genes encoding the catalase-peroxidase enzyme (katG) that is associated with resistance to isoniazid. Similarly, two embB homologues were identified in the M. aurum genome. In addition to describing for the first time the genome of M. aurum, this work provides a resource to aid the use of M. aurum in studies to develop improved drugs for the pathogenic mycobacteria M. tuberculosis and M. leprae.

The draft genome of Mycobacterium aurum , a potential model organism for investigating drugs against Mycobacterium tuberculosis and Mycobacterium leprae

Directory of Open Access Journals (Sweden)

Jody Phelan

2015-01-01

Full Text Available Mycobacterium aurum (M. aurum is an environmental mycobacteria that has previously been used in studies of anti-mycobacterial drugs due to its fast growth rate and low pathogenicity. The M. aurum genome has been sequenced and assembled into 46 contigs, with a total length of 6.02 Mb containing 5684 annotated protein-coding genes. A phylogenetic analysis using whole genome alignments positioned M. aurum close to Mycobacterium vaccae and Mycobacterium vanbaalenii, within a clade related to fast-growing mycobacteria. Large-scale genomic rearrangements were identified by comparing the M. aurum genome to those of Mycobacterium tuberculosis and Mycobacterium leprae. M. aurum orthologous genes implicated in resistance to anti-tuberculosis drugs in M. tuberculosis were observed. The sequence identity at the DNA level varied from 68.6% for pncA (pyrazinamide drug-related to 96.2% for rrs (streptomycin, capreomycin. We observed two homologous genes encoding the catalase-peroxidase enzyme (katG that is associated with resistance to isoniazid. Similarly, two emb B homologues were identified in the M. aurum genome. In addition to describing for the first time the genome of M. aurum , this work provides a resource to aid the use of M. aurum in studies to develop improved drugs for the pathogenic mycobacteria M. tuberculosis and M. leprae.

7 CFR 1131.13 - Producer milk.

Science.gov (United States)

2010-01-01

... Handling Definitions § 1131.13 Producer milk. Producer milk means the skim milk (or the skim equivalent of components of skim milk) and butterfat in milk of a producer that is: (a) Received by the operator of a pool... percentage in paragraph (d)(2) of this section may be increased or decreased by the market administrator if...

7 CFR 760.303 - Eligible livestock producer.

Science.gov (United States)

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Eligible livestock producer. 760.303 Section 760.303... AGRICULTURE SPECIAL PROGRAMS INDEMNITY PAYMENT PROGRAMS Livestock Forage Disaster Program § 760.303 Eligible livestock producer. (a) To be considered an eligible livestock producer, the eligible producer on a farm...

Impact of Mycobacterium ulcerans biofilm on transmissibility to ecological niches and Buruli ulcer pathogenesis.

Directory of Open Access Journals (Sweden)

Laurent Marsollier

2007-05-01

Full Text Available The role of biofilms in the pathogenesis of mycobacterial diseases remains largely unknown. Mycobacterium ulcerans, the etiological agent of Buruli ulcer, a disfiguring disease in humans, adopts a biofilm-like structure in vitro and in vivo, displaying an abundant extracellular matrix (ECM that harbors vesicles. The composition and structure of the ECM differs from that of the classical matrix found in other bacterial biofilms. More than 80 proteins are present within this extracellular compartment and appear to be involved in stress responses, respiration, and intermediary metabolism. In addition to a large amount of carbohydrates and lipids, ECM is the reservoir of the polyketide toxin mycolactone, the sole virulence factor of M. ulcerans identified to date, and purified vesicles extracted from ECM are highly cytotoxic. ECM confers to the mycobacterium increased resistance to antimicrobial agents, and enhances colonization of insect vectors and mammalian hosts. The results of this study support a model whereby biofilm changes confer selective advantages to M. ulcerans in colonizing various ecological niches successfully, with repercussions for Buruli ulcer pathogenesis.

Analysis of potential fumonisin-producing Fusarium species in corn products from three main maize-producing areas in eastern China.

Science.gov (United States)

Zhang, Liping; Wang, Jiansheng; Zhang, Chulong; Wang, Qiaomei

2013-02-01

Fusarium species are common fungal contaminants of maize and a number of them can produce mycotoxin fumonisins. China is one of the largest maize producers in the world. This study investigated the contamination of maize samples from three areas in eastern China by Fusarium and fumonisin-producing fungi as well as their fumonisin-producing potential. A total of 22 Fusarium strains were isolated, 19 of which were able to produce fumonisin. Among the 19 strains, 16 belonged to F. verticillioides, two to F. subglutinans and one to F. proliferatum. The majority (17/19) of the fumonisin-forming strains were high FB(1) producers, which is a potential health risk for the population in these areas. Fusarium contamination in samples from the mideastern area was the most serious (11 Fusarium strains, with nine producing fumonisin, isolated from 24 samples), followed by the northeastern area (nine Fusarium strains, with all nine producing fumonisin, isolated from 21 samples) and the southeastern area (two Fusarium strains, with one producing fumonisin, isolated from 19 samples). Although the overall levels of FBs and contamination by fumonisin-producing fungi in corn samples were not serious, the contaminating Fusarium strains possessed fairly strong toxicogenic ability and potential risk for food safety. Copyright © 2012 Society of Chemical Industry.

Producing superhydrophobic roof tiles

International Nuclear Information System (INIS)

Carrascosa, Luis A M; Facio, Dario S; Mosquera, Maria J

2016-01-01

Superhydrophobic materials can find promising applications in the field of building. However, their application has been very limited because the synthesis routes involve tedious processes, preventing large-scale application. A second drawback is related to their short-term life under outdoor conditions. A simple and low-cost synthesis route for producing superhydrophobic surfaces on building materials is developed and their effectiveness and their durability on clay roof tiles are evaluated. Specifically, an organic–inorganic hybrid gel containing silica nanoparticles is produced. The nanoparticles create a densely packed coating on the roof tile surface in which air is trapped. This roughness produces a Cassie–Baxter regime, promoting superhydrophobicity. A surfactant, n-octylamine, was also added to the starting sol to catalyze the sol–gel process and to coarsen the pore structure of the gel network, preventing cracking. The application of ultrasound obviates the need to use volatile organic compounds in the synthesis, thereby making a ‘green’ product. It was also demonstrated that a co-condensation process effective between the organic and inorganic species is crucial to obtain durable and effective coatings. After an aging test, high hydrophobicity was maintained and water absorption was completely prevented for the roof tile samples under study. However, a transition from a Cassie–Baxter to a Wenzel state regime was observed as a consequence of the increase in the distance between the roughness pitches produced by the aging of the coating. (paper)

Produced Water Management and Beneficial Use

International Nuclear Information System (INIS)

Brown, Terry; Frost, Carol; Hayes, Thomas; Heath, Leo; Johnson, Drew; Lopez, David; Saffer, Demian; Urynowicz, Michael; Wheaton, John; Zoback, Mark

2007-01-01

Large quantities of water are associated with the production of coalbed methane (CBM) in the Powder River Basin (PRB) of Wyoming. The chemistry of co-produced water often makes it unsuitable for subsequent uses such as irrigated agriculture. However, co-produced waters have substantial potential for a variety of beneficial uses. Achieving this potential requires the development of appropriate water management strategies. There are several unique characteristics of co-produced water that make development of such management strategies a challenge. The production of CBM water follows an inverse pattern compared to traditional wells. CBM wells need to maintain low reservoir pressures to promote gas production. This need renders the reinjection of co-produced waters counterproductive. The unique water chemistry of co-produced water can reduce soil permeability, making surface disposal difficult. Unlike traditional petroleum operations where co-produced water is an undesirable by-product, co-produced water in the PRB often is potable, making it a highly valued resource in arid western states. This research project developed and evaluated a number of water management options potentially available to CBM operators. These options, which focus on cost-effective and environmentally-sound practices, fall into five topic areas: Minimization of Produced Water, Surface Disposal, Beneficial Use, Disposal by Injection and Water Treatment. The research project was managed by the Colorado Energy Research Institute (CERI) at the Colorado School of Mines (CSM) and involved personnel located at CERI, CSM, Stanford University, Pennsylvania State University, the University of Wyoming, the Argonne National Laboratory, the Gas Technology Institute, the Montana Bureau of Mining and Geology and PVES Inc., a private firm

Produced Water Management and Beneficial Use

Energy Technology Data Exchange (ETDEWEB)

Terry Brown; Carol Frost; Thomas Hayes; Leo Heath; Drew Johnson; David Lopez; Demian Saffer; Michael Urynowicz; John Wheaton; Mark Zoback

2007-10-31

Large quantities of water are associated with the production of coalbed methane (CBM) in the Powder River Basin (PRB) of Wyoming. The chemistry of co-produced water often makes it unsuitable for subsequent uses such as irrigated agriculture. However, co-produced waters have substantial potential for a variety of beneficial uses. Achieving this potential requires the development of appropriate water management strategies. There are several unique characteristics of co-produced water that make development of such management strategies a challenge. The production of CBM water follows an inverse pattern compared to traditional wells. CBM wells need to maintain low reservoir pressures to promote gas production. This need renders the reinjection of co-produced waters counterproductive. The unique water chemistry of co-produced water can reduce soil permeability, making surface disposal difficult. Unlike traditional petroleum operations where co-produced water is an undesirable by-product, co-produced water in the PRB often is potable, making it a highly valued resource in arid western states. This research project developed and evaluated a number of water management options potentially available to CBM operators. These options, which focus on cost-effective and environmentally-sound practices, fall into five topic areas: Minimization of Produced Water, Surface Disposal, Beneficial Use, Disposal by Injection and Water Treatment. The research project was managed by the Colorado Energy Research Institute (CERI) at the Colorado School of Mines (CSM) and involved personnel located at CERI, CSM, Stanford University, Pennsylvania State University, the University of Wyoming, the Argonne National Laboratory, the Gas Technology Institute, the Montana Bureau of Mining and Geology and PVES Inc., a private firm.

Analysis of activity in swine producers group based on agricultural producers association in Biała district

Directory of Open Access Journals (Sweden)

Damian Knecht

2013-03-01

Full Text Available The process of pigs producer groups formation in Poland is quite dynamic. Currently on the pork market 181 groups operate, which includes about 4000 swine producers. The aim of this study was to characterize the activities of the Agricultural Producers Association in Biała District. The research tool was a personal questionnaire and the research sample consisted of 30 farmers. It has been shown that after joining the producers group, the investigated households reported an increase in sales volume and improved the flock production parameters. Majority of the respondents were not satisfied with the cooperation with meat processing companies.

Producing deep-water hydrocarbons

International Nuclear Information System (INIS)

Pilenko, Thierry

2011-01-01

Several studies relate the history and progress made in offshore production from oil and gas fields in relation to reserves and the techniques for producing oil offshore. The intention herein is not to review these studies but rather to argue that the activities of prospecting and producing deep-water oil and gas call for a combination of technology and project management and, above all, of devotion and innovation. Without this sense of commitment motivating men and women in this industry, the human adventure of deep-water production would never have taken place

Tekna's produced water conference 2005

International Nuclear Information System (INIS)

2005-01-01

The conference has 22 presentations discussing topics on discharge reduction, produced water quality, produced water re-injection, chemicals particularly environmentally friendly ones, separation technology, reservoir souring, total water management systems, pollution, oil in water problems and platform operation. Various field tests and experiences particularly from the offshore petroleum sector are presented (tk)

Faecal carriage of extended-spectrum b-lactamase-producing and AMpC b-lactamase-producing bacteria among Danish army recruits

DEFF Research Database (Denmark)

Hammerum, A.M; Lester, C.H; Jakobsen, L

2011-01-01

During May and June 2008, 84 Danish army recruits were tested for faecal carriage of extended-spectrum b-lactamase (ESBL)- producing and AmpC b-lactamase-producing bacteria. Three ESBL-producing (CTX-M-14a) Escherichia coli isolates, two AmpC-producing (CMY-2) E. coli isolates and one Amp...

Produced water - composition and analysis

International Nuclear Information System (INIS)

Kvernheim, Arne Lund

1998-01-01

Produced water can be defined as ''High volume waste-water separated from oil and gas that is produced from subsurface formations''. The water contains aliphatic and aromatic hydrocarbons, particulate matter and soluble salts as well as elements originating from formations and from sea water injections. Residues of chemicals may also be present. The accepted North Sea discharge limit is 40 ppm. In this presentation the focus will be on the chemical composition of produced water and on the challenges involved in developing and implementing analytical methods. The focus will also be on the development of a new oil-in-water analytical method as a replacement for the Freon method. 7 refs., 1 tab

Comparison of the virulence of exopolysaccharide-producing Prevotella intermedia to exopolysaccharide non-producing periodontopathic organisms.

Science.gov (United States)

Yamanaka, Takeshi; Yamane, Kazuyoshi; Furukawa, Tomoyo; Matsumoto-Mashimo, Chiho; Sugimori, Chieko; Nambu, Takayuki; Obata, Noboru; Walker, Clay B; Leung, Kai-Poon; Fukushima, Hisanori

2011-08-25

Evidence in the literature suggests that exopolysaccharides (EPS) produced by bacterial cells are essential for the expression of virulence in these organisms. Secreted EPSs form the framework in which microbial biofilms are built. This study evaluates the role of EPS in Prevotella intermedia for the expression of virulence. This evaluation was accomplished by comparing EPS-producing P. intermedia strains 17 and OD1-16 with non-producing P. intermedia ATCC 25611 and Porphyromonas gingivalis strains ATCC 33277, 381 and W83 for their ability to induce abscess formation in mice and evade phagocytosis. EPS-producing P. intermedia strains 17 and OD1-16 induced highly noticeable abscess lesions in mice at 107 colony-forming units (CFU). In comparison, P. intermedia ATCC 25611 and P. gingivalis ATCC 33277, 381 and W83, which all lacked the ability to produce viscous materials, required 100-fold more bacteria (109 CFU) in order to induce detectable abscess lesions in mice. Regarding antiphagocytic activity, P. intermedia strains 17 and OD1-16 were rarely internalized by human polymorphonuclear leukocytes, but other strains were readily engulfed and detected in the phagosomes of these phagocytes. These results demonstrate that the production of EPS by P. intermedia strains 17 and OD1-16 could contribute to the pathogenicity of this organism by conferring their ability to evade the host's innate defence response.

Methods and systems for producing syngas

Science.gov (United States)

Hawkes, Grant L; O& #x27; Brien, James E; Stoots, Carl M; Herring, J. Stephen; McKellar, Michael G; Wood, Richard A; Carrington, Robert A; Boardman, Richard D

2013-02-05

Methods and systems are provided for producing syngas utilizing heat from thermochemical conversion of a carbonaceous fuel to support decomposition of at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells. Simultaneous decomposition of carbon dioxide and water or steam by one or more solid-oxide electrolysis cells may be employed to produce hydrogen and carbon monoxide. A portion of oxygen produced from at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells is fed at a controlled flow rate in a gasifier or combustor to oxidize the carbonaceous fuel to control the carbon dioxide to carbon monoxide ratio produced.

Producing liquid fuels from biomass

Science.gov (United States)

Solantausta, Yrjo; Gust, Steven

The aim of this survey was to compare, on techno-economic criteria, alternatives of producing liquid fuels from indigenous raw materials in Finland. Another aim was to compare methods under development and prepare a proposal for steering research related to this field. Process concepts were prepared for a number of alternatives, as well as analogous balances and production and investment cost assessments for these balances. Carbon dioxide emissions of the alternatives and the price of CO2 reduction were also studied. All the alternatives for producing liquid fuels from indigenous raw materials are utmost unprofitable. There are great differences between the alternatives. While the production cost of ethanol is 6 to 9 times higher than the market value of the product, the equivalent ratio for substitute fuel oil produced from peat by pyrolysis is 3 to 4. However, it should be borne in mind that the technical uncertainties related to the alternatives are of different magnitude. Production of ethanol from barley is of commercial technology, while biomass pyrolysis is still under development. If the aim is to reach smaller carbon dioxide emissions by using liquid biofuels, the most favorable alternative is pyrolysis oil produced from wood. Fuels produced from cultivated biomass are more expensive ways of reducing CO2 emissions. Their potential of reducing CO2 emissions in Finland is insignificant. Integration of liquid fuel production to some other production line is more profitable.

Produced water treatment methods for SAGD

Energy Technology Data Exchange (ETDEWEB)

Minnich, K. [Veolia Water Solutions and Technologies, Mississauga, ON (Canada)

2008-07-01

Produced water treatment methods for steam assisted gravity drainage (SAGD) processes were presented. Lime softening is used to remove sludge before weak acid cation processes. However, the process is not reliable in cold climates, and disposal of the sludge is now posing environmental problems in Alberta. High pH MVC evaporation processes use sodium hydroxide (NaOH) additions to prevent silica scaling. However the process produces silica wastes that are difficult to dispose of. The sorption slurry process was designed to reduce the use of caustic soda and develop a cost-effective method of disposing evaporator concentrates. The method produces 98 per cent steam quality for SAGD injection. Silica is sorbed onto crystals in order to prevent silica scaling. The evaporator concentrate from the process is suitable for on- and off-site deep well disposal. The ceramic membrane process was designed to reduce the consumption of chemicals and improve the reliability of water treatment processes. The ion exchange desilication process uses 80 per cent less power and produces 80 per cent fewer CO{sub 2} emissions than MVC evaporators. A comparative operating cost evaluation of various electric supply configurations and produced water treatment processes was also included, as well as an analysis of produced water chemistry. tabs., figs.

Comparative genomics of citric-acid-producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88

DEFF Research Database (Denmark)

Andersen, Mikael Rørdam; Salazar, Margarita Pena; Schaap, Peter J.

2011-01-01

The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme......-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compel additional exploration. We therefore undertook whole-genome sequencing of the acidogenic A. niger wild-type strain (ATCC 1015) and produced a genome sequence of very high quality. Only 15...

Method of producing molybdenum-99

Science.gov (United States)

Pitcher, Eric John

2013-05-28

Method of producing molybdenum-99, comprising accelerating ions by means of an accelerator; directing the ions onto a metal target so as to generate neutrons having an energy of greater than 10 MeV; directing the neutrons through a converter material comprising techentium-99 to produce a mixture comprising molybdenum-99; and, chemically extracting the molybdenum-99 from the mixture.

Must producers earn a resource rent?

International Nuclear Information System (INIS)

Austvik, Ole Gunnar

2003-01-01

In petroleum producing countries it has been a prevailing opinion that a resource rent should be earned by petroleum producers due to the commodities' non-renewable nature. An important element in this logic is that the supply of oil and natural gas is limited to relatively few places in the world. As the resources are exploited, the remaining reserves are reduced. What is extracted today cannot be extracted tomorrow. Rationing of the scarce resource takes place through pricing mechanisms. Due to the scarcity the consumers must pay a higher price than the marginal production costs, so that the amounts supplied and demanded become equal. Most producers of oil and gas and not just the ones that produce the cheapest, have therefore until now earned an economic rent

Multifaceted role of lipids in Mycobacterium leprae.

Science.gov (United States)

Kaur, Gurkamaljit; Kaur, Jagdeep

2017-03-01

Mycobacterium leprae must adopt a metabolic strategy and undergo various metabolic alterations upon infection to survive inside the human body for years in a dormant state. A change in lipid homeostasis upon infection is highly pronounced in Mycobacterium leprae. Lipids play an essential role in the survival and pathogenesis of mycobacteria. Lipids are present in several forms and serve multiple roles from being a source of nutrition, providing rigidity, evading the host immune response to serving as virulence factors, etc. The synthesis and degradation of lipids is a highly regulated process and is the key to future drug designing and diagnosis for mycobacteria. In the current review, an account of the distinct roles served by lipids, the mechanism of their synthesis and degradation has been elucidated.

Putative in vitro expressed gene fragments unique to Mycobacterium avium subspecies para tuberculosis

DEFF Research Database (Denmark)

Nielsen, Kirstine Klitgaard; Ahrens, Peter

2002-01-01

By a suppression subtractive hybridization based method, nine novel Mycobacterium avium subsp. para tuberculosis (M. para tuberculosis) fragments of between 318 and 596 bp have been identified and characterized. Database search revealed little or no similarity with other mycobacteria. The uniquen......By a suppression subtractive hybridization based method, nine novel Mycobacterium avium subsp. para tuberculosis (M. para tuberculosis) fragments of between 318 and 596 bp have been identified and characterized. Database search revealed little or no similarity with other mycobacteria....... The uniqueness and diagnostic potential of seven of these fragments in relation to M. paratuberculosis closest relative Mycobacterium avium subsp. avium (M. avium) was confirmed by species-specific PCR and Southern blot. Furthermore, RT-PCR indicated that eight of the nine fragments originate from areas...

[Identification of mycobacteria by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry--using reference strains and clinical isolates of Mycobacterium].

Science.gov (United States)

Niitsuma, Katsunao; Saito, Miwako; Koshiba, Shizuko; Kaneko, Michiyo

2014-05-01

Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) method is being played an important role for the inspection of clinical microorganism as a rapid and the price reduction. Mass spectra obtained by measuring become points of identification whether the peak pattern match any species mass spectral pattern. We currently use MALDI-TOF MS for rapid and accurate diagnosis of inactivated reference and clinical isolates of Mycobacterium because of the improved pretreatment techniques compared with former inspection methods that pose a higher risk of infection to the operator. The identification matching rate of score value (SV) peak pattern spectra was compared with that of conventional methods such as strain diffusion/amplification. Also, cultures were examined after a fixed number of days. Compared with the initial inspection technique, the pretreatment stage of current MALDI-TOF MS inspection techniques can improve the analysis of inactivated acid-fast bacteria that are often used as inspection criteria strains of clinical isolates. Next, we compared the concordance rate for identification between MALDI-TOF MS and conventional methods such as diffusion/amplification by comparison of peak pattern spectra and evaluated SV spectra to identify differences in the culture media after the retention period. In examination of 158 strains of clinical isolated Mycobacterium tuberculosis complex (MTC), the identification coincidence rate in the genus level in a matching pattern was 99.4%, when the species level was included 94.9%. About 37 strains of nontuberculous mycobacteria (NTM), the identification coincidence rate in the genus level was 94.6%. M. bovis BCG (Tokyo strain) in the reference strain was judged by the matching pattern to be MTC, and it suggested that they are M. tuberculosis and affinity species with high DNA homology. Nontuberculous mycobacterial M. gordonae strain JATA 33-01 shared peak pattern spectra, excluding the

DOES ELECTRIC CAR PRODUCE EMISSIONS?

Directory of Open Access Journals (Sweden)

Vladimír RIEVAJ

2017-03-01

Full Text Available This article focuses on the comparison of the amount of emissions produced by vehicles with a combustion engine and electric cars. The comparison, which is based on the LCA factor results, indicates that an electric car produces more emissions than a vehicle with combustion engine. The implementation of electric cars will lead to an increase in the production of greenhouse gases.

Wintertime Emissions from Produced Water Ponds

Science.gov (United States)

Evans, J.; Lyman, S.; Mansfield, M. L.

2013-12-01

Every year oil and gas drilling in the U.S. generates billions of barrels of produced water (water brought to the surface during oil or gas production). Efficiently disposing of produced water presents a constant financial challenge for producers. The most noticeable disposal method in eastern Utah's Uintah Basin is the use of evaporation ponds. There are 427 acres of produced water ponds in the Uintah Basin, and these were used to evaporate more than 5 million barrels of produced water in 2012, 6% of all produced water in the Basin. Ozone concentrations exceeding EPA standards have been observed in the Uintah Basin during winter inversion conditions, with daily maximum 8 hour average concentrations at some research sites exceeding 150 parts per billion. Produced water contains ozone-forming volatile organic compounds (VOC) which escape into the atmosphere as the water is evaporated, potentially contributing to air quality problems. No peer-reviewed study of VOC emissions from produced water ponds has been reported, and filling this gap is essential for the development of accurate emissions inventories for the Uintah Basin and other air sheds with oil and gas production. Methane, carbon dioxide, and VOC emissions were measured at three separate pond facilities in the Uintah Basin in February and March of 2013 using a dynamic flux chamber. Pond emissions vary with meteorological conditions, so measurements of VOC emissions were collected during winter to obtain data relevant to periods of high ozone production. Much of the pond area at evaporation facilities was frozen during the study period, but areas that actively received water from trucks remained unfrozen. These areas accounted for 99.2% of total emissions but only 9.5% of the total pond area on average. Ice and snow on frozen ponds served as a cap, prohibiting VOC from being emitted into the atmosphere. Emissions of benzene, toluene, and other aromatic VOCs averaged over 150 mg m-2 h-1 from unfrozen pond

Inventory transparency for agricultural produce through IOT

Science.gov (United States)

Srinivasan, S. P.; Sorna Shanthi, D.; Anand, Aashish V.

2017-06-01

Re-structuring the practices of traditional inventory management is becoming more essential to optimize the supply chain transparency and accuracy of agricultural produce. A flexible and transparent inventory management system is becoming the need of any agricultural commodity. It was noticed that the major setback for the farmers who are the suppliers of the farm produce is due to poor supply chain integration. The recent advent technologies and IT explosion can bring up a greater impact in the process of storing, tracking, distributing and monitoring perishable agriculture produce of day to day life. The primary focus of this paper is to integrate IoT into inventory management and other inbound logistics management of agriculture produce. The unique features of agricultural produce like a prediction of supply, demand, the location of warehouses, distribution and tracking of inventory can be integrated through IoT. This paper proposes a conceptual framework for inventory management transparency involved in the supply chain of agriculture produce.

Effects of air pollution on respiratory health

Directory of Open Access Journals (Sweden)

Hasan Bayram

2015-01-01

In conclusion, air pollutants can induce respiratory mortality and morbidity by leading to airway and lung inflammation and impairing the airway defence system against noxious agents and microorganisms such as mycobacteria TB.

24 CFR 3280.707 - Heat producing appliances.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Heat producing appliances. 3280.707... Systems § 3280.707 Heat producing appliances. (a) Heat-producing appliances and vents, roof jacks and... appliance, the heating appliance shall be installed by the manufacturer of the manufactured home in...

US producers in a competitive market

International Nuclear Information System (INIS)

Beck, M.

1987-01-01

The current (1986) situation in the world-wide uranium market is explained and the competitiveness of United States producers is considered in this context. Historical export contracts by US producers are examined to evaluate how sales quantities by region have changed. The influence of inflation and exchange rates on production costs are considered. The threat of US protectionism is discussed. Despite the contraction of the US uranium industry in recent years a number of US producers have remained competitive. Factors which could increase US competitiveness are listed. (U.K.)

Method of producing grouting mortar

Energy Technology Data Exchange (ETDEWEB)

Shelomov, I K; Alchina, S I; Dizer, E I; Gruzdeva, G A; Nikitinskii, V I; Sabirzyanov, A K

1980-10-07

A method of producing grouting mortar by mixing the cement with an aqueous salt solution is proposed. So as to increase the quality of the mortar through an acceleration of the time for hardening, the mixture is prepared in two stages, in the first of which 20-30% of the entire cement batch hardens, and in the second of which the remainder of the cement hardens; 1-3-% of an aqueous salt solution is used in quantities of 0.5/1 wt.-% of weight of the cement. The use of this method of producing grouting mortar helps to increase the flexural strength of the cement brick up to 50% after two days ageing by comparison with the strength of cement brick produced from grouting mortar by ordinary methods utilizing identical quantities of the initial components (cement, water, chloride).

Uracil excision repair in Mycobacterium tuberculosis cell-free extracts.

Science.gov (United States)

Kumar, Pradeep; Bharti, Sanjay Kumar; Varshney, Umesh

2011-05-01

Uracil excision repair is ubiquitous in all domains of life and initiated by uracil DNA glycosylases (UDGs) which excise the promutagenic base, uracil, from DNA to leave behind an abasic site (AP-site). Repair of the resulting AP-sites requires an AP-endonuclease, a DNA polymerase, and a DNA ligase whose combined activities result in either short-patch or long-patch repair. Mycobacterium tuberculosis, the causative agent of tuberculosis, has an increased risk of accumulating uracils because of its G + C-rich genome, and its niche inside host macrophages where it is exposed to reactive nitrogen and oxygen species, two major causes of cytosine deamination (to uracil) in DNA. In vitro assays to study DNA repair in this important human pathogen are limited. To study uracil excision repair in mycobacteria, we have established assay conditions using cell-free extracts of M. tuberculosis and M. smegmatis (a fast-growing mycobacterium) and oligomer or plasmid DNA substrates. We show that in mycobacteria, uracil excision repair is completed primarily via long-patch repair. In addition, we show that M. tuberculosis UdgB, a newly characterized family 5 UDG, substitutes for the highly conserved family 1 UDG, Ung, thereby suggesting that UdgB might function as backup enzyme for uracil excision repair in mycobacteria. Copyright © 2011 Elsevier Ltd. All rights reserved.

Characterization of Mycobacterium paratuberculosis by gas-liquid and thin-layer chromatography and rapid demonstration of mycobactin dependence using radiometric methods

International Nuclear Information System (INIS)

Damato, J.J.; Knisley, C.; Collins, M.T.

1987-01-01

Thirty-six Mycobacterium paratuberculosis isolates of bovine, caprine, and ovine origins were evaluated by using gas-liquid chromatography (GLC), thin-layer chromatography (TLC), and BACTEC 7H12 Middlebrook TB medium in an effort to more rapidly differentiate this group of organisms from other mycobacteria. Bacterial suspensions (0.1 ml) were inoculated by syringe into 7H12 broth containing 2 micrograms of mycobactin P per ml and control broth without mycobactin P. Cultures were incubated at 37 0 C and read daily with a BACTEC Model 301. After 8 days of incubation, the growth index readings for the test broths containing mycobactin P were twice those of the control broths without mycobactin P. Sixty-five isolates of mycobacteria other than M. paratuberculosis were also examined. No difference was noted between the growth index readings of control and mycobactin-containing broths. Except for Mycobacterium avium-Mycobacterium intracellulare, TLC studies differentiated M. paratuberculosis from the other mycobacterial species tested. The GLC data reveal that all M. paratuberculosis isolates had a distinctive peak (14A) which was not found among M. avium-M. intracellulare complex organisms. These data indicate that 7H12 radiometric broth was able to rapidly demonstrate the mycobactin dependence of M. paratuberculosis and GLC and TLC procedures were capable of rapidly differentiating this organism from the other mycobacteria studied

The draft genome of Mycobacterium aurum, a potential model organism for investigating drugs against Mycobacterium tuberculosis and Mycobacterium leprae.

Science.gov (United States)

Phelan, Jody; Maitra, Arundhati; McNerney, Ruth; Nair, Mridul; Gupta, Antima; Coll, Francesc; Pain, Arnab; Bhakta, Sanjib; Clark, Taane G

2015-09-01

Mycobacterium aurum (M. aurum) is an environmental mycobacteria that has previously been used in studies of anti-mycobacterial drugs due to its fast growth rate and low pathogenicity. The M. aurum genome has been sequenced and assembled into 46 contigs, with a total length of 6.02Mb containing 5684 annotated protein-coding genes. A phylogenetic analysis using whole genome alignments positioned M. aurum close to Mycobacterium vaccae and Mycobacterium vanbaalenii, within a clade related to fast-growing mycobacteria. Large-scale genomic rearrangements were identified by comparing the M. aurum genome to those of Mycobacterium tuberculosis and Mycobacterium leprae. M. aurum orthologous genes implicated in resistance to anti-tuberculosis drugs in M. tuberculosis were observed. The sequence identity at the DNA level varied from 68.6% for pncA (pyrazinamide drug-related) to 96.2% for rrs (streptomycin, capreomycin). We observed two homologous genes encoding the catalase-peroxidase enzyme (katG) that is associated with resistance to isoniazid. Similarly, two embB homologues were identified in the M. aurum genome. In addition to describing for the first time the genome of M. aurum, this work provides a resource to aid the use of M. aurum in studies to develop improved drugs for the pathogenic mycobacteria M. tuberculosis and M. leprae. Copyright © 2015 Asian-African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

7 CFR 1206.8 - Foreign producer.

Science.gov (United States)

2010-01-01

... produced, mangos beyond the person's own family use and having value at first point of sale. ... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE MANGO PROMOTION, RESEARCH, AND INFORMATION Mango Promotion, Research, and Information Order Definitions § 1206.8 Foreign producer. Foreign...

USA coal producer perspective

Energy Technology Data Exchange (ETDEWEB)

Porco, J. [Alpha Natural Resources, Latrobe, PA (US). Alpha Energy Global Marketing

2004-07-01

The focus is on the Central Appalachian coal industry. Alpha Natural Resources was formed in 2002 from Pittston Coal's Virginia and Coastal operations. AMCI's U.S. operations and Mears Enterprises in Pennsylvania were acquired later. The company produces 20-21 million tonnes per year and sells 20 million tonnes of steam coal and 10 million tonnes of exports, including some coal that is brokered. Foundry coke is a major product. Capital investment has resulted in increased productivity. Central Appalachia is expected to continue as a significant coal-producing region for supplying metallurgical coke. Production is expected to stabilize, but not increase; so the mines will have a longer life. 31 slides/overheads are included.

Genotyping of Mycobacterium avium subsp. avium isolates from naturally infected lofts of domestic pigeons by IS901 RFLP

Directory of Open Access Journals (Sweden)

K Parvandar Asadollahi

2015-01-01

In conclusion: It is suggested that more DNA fingerprinting tests for non-tuberculous Mycobacteria, particularly M. avium complex isolated from infected birds and humans, be conducted to find the source of their infections.

Occurrence and characteristics of extended-spectrum β-lactamase (ESBL producing Enterobacteriaceae in food producing animals, minced meat and raw milk

Directory of Open Access Journals (Sweden)

Geser Nadine

2012-03-01

Full Text Available Abstract Background The impact of food animals as a possible reservoir for extended-spectrum beta-lactamase (ESBL producing Enterobacteriaceae, and the dissemination of such strains into the food production chain need to be assessed. In this study 334 fecal samples from pigs, cattle, chicken and sheep were investigated at slaughter. Additionally, 100 raw milk samples, representing bulk tank milk of 100 different dairy farms, 104 minced meat (pork and beef samples and 67 E. coli isolates from cattle E. coli mastitis were analyzed. Results As many as 15.3% of the porcine, 13.7% of the bovine, 8.6% of the sheep and 63.4% of the chicken fecal samples yielded ESBL producers after an enrichment step. In contrast, none of the minced meat, none of the bulk tank milk samples and only one of the mastitis milk samples contained ESBL producing strains. Of the total of 91 isolates, 89 were E. coli, one was Citrobacter youngae and one was Enterobacter cloacae. PCR analysis revealed that 78 isolates (85.7% produced CTX-M group 1 ESBLs while six isolates (6.6% produced CTX-M group 9 enzymes. Five detected ESBLs (5.5% belonged to the SHV group and 2 isolates (2.2% contained a TEM-type enzyme. A total of 27 CTX-M producers were additionally PCR-positive for TEM-beta-lactamase. The ESBL-encoding genes of 53 isolates were sequenced of which 34 produced CTX-M-1, 6 produced CTX-M-14, 5 produced CTX-M-15 and also 5 produced SHV-12. Two isolates produced TEM-52 and one isolate expressed a novel CTX-M group 1 ESBL, CTX-M-117. One isolate--aside from a CTX-M ESBL-- contained an additional novel TEM-type broad-spectrum beta-lactamase, TEM-186. Conclusions The relatively high rates of ESBL producers in food animals and the high genetic diversity among these isolates are worrisome and indicate an established reservoir in farm animals.

Exopolysaccharides produced by lactic acid bacteria

NARCIS (Netherlands)

Caggianiello, Graziano; Kleerebezem, Michiel; Spano, Giuseppe

2016-01-01

A wide range of lactic acid bacteria (LAB) is able to produce capsular or extracellular polysaccharides, with various chemical compositions and properties. Polysaccharides produced by LAB alter the rheological properties of the matrix in which they are dispersed, leading to typically viscous and

Isolation of hydrogen-producing bacteria from biodigesters

Energy Technology Data Exchange (ETDEWEB)

Ferreira, S.V.; Servulo, E.F.C.; Da Silva, I.M.; Martelli, H.L.

1984-01-01

Two H2-producing strains belonging to the Enterobacteriaceae were isolated from biodigesters, fed sugarcane distillation slops, from acetone-butanol fermentation, under anaerobic conditions. H2 and CO2 were the only gases produced from glucose. H2 was 40.87% of the total gas produced by Citrobacter freundii, and 57.74% when Enterobacter agglomerans was assayed.

Bacteriocin-producing Enterococci from Rabbit Meat

Directory of Open Access Journals (Sweden)

Szabóová, R.

2012-01-01

Full Text Available Aims: Enterococci are lactic acid bacteria belonging to the division Firmicutes. They occur in different ecosystems, rabbits including. Enterococci can possess probiotic properties and produce antimicrobial substances-bacteriocins. Rabbit meat as nutritionally healthy food offers novel source to study bacteriocin-producing and/or probiotic enterococci. Methodology and results: Enterococci were detected from rabbit meat samples (42. Most of the isolates were allotted to the species Enterococcus faecium by PCR method. The isolates have possessed the structural genes for enterocins A, P, B production. The inhibitory substances produced by the isolated enterococci inhibited the growth of 12 indicators. Of 34 isolates, 15 strains have shown the antimicrobial activity against L. monocytogenes CCM 4699, 12 strains against S. aureus 3A3, 10 strains against S. aureus 5A2 as well as Salmonella enterica serovar Enteritidis PT4. Moreover, enterococci have tolerated 5 % bile, low pH; they have produced lactid acid in the amount from 0.740 ± 0.091 to 1.720 ± 0.095 mmol/l. The isolates were mostly sensitive to antibiotics. Conclusion, significance and impact of study: Bacteriocin-producing strain E. faecium M3a has been selected for more detail characterization of its bacteriocin and probiotic properties with the aim for its further application as an additive.

Bacillus calmette-guerin infection in NADPH oxidase deficiency: defective mycobacterial sequestration and granuloma formation.

Directory of Open Access Journals (Sweden)

Christine Deffert

2014-09-01

Full Text Available Patients with chronic granulomatous disease (CGD lack generation of reactive oxygen species (ROS through the phagocyte NADPH oxidase NOX2. CGD is an immune deficiency that leads to frequent infections with certain pathogens; this is well documented for S. aureus and A. fumigatus, but less clear for mycobacteria. We therefore performed an extensive literature search which yielded 297 cases of CGD patients with mycobacterial infections; M. bovis BCG was most commonly described (74%. The relationship between NOX2 deficiency and BCG infection however has never been studied in a mouse model. We therefore investigated BCG infection in three different mouse models of CGD: Ncf1 mutants in two different genetic backgrounds and Cybb knock-out mice. In addition, we investigated a macrophage-specific rescue (transgenic expression of Ncf1 under the control of the CD68 promoter. Wild-type mice did not develop severe disease upon BCG injection. In contrast, all three types of CGD mice were highly susceptible to BCG, as witnessed by a severe weight loss, development of hemorrhagic pneumonia, and a high mortality (∼ 50%. Rescue of NOX2 activity in macrophages restored BCG resistance, similar as seen in wild-type mice. Granulomas from mycobacteria-infected wild-type mice generated ROS, while granulomas from CGD mice did not. Bacterial load in CGD mice was only moderately increased, suggesting that it was not crucial for the observed phenotype. CGD mice responded with massively enhanced cytokine release (TNF-α, IFN-γ, IL-17 and IL-12 early after BCG infection, which might account for severity of the disease. Finally, in wild-type mice, macrophages formed clusters and restricted mycobacteria to granulomas, while macrophages and mycobacteria were diffusely distributed in lung tissue from CGD mice. Our results demonstrate that lack of the NADPH oxidase leads to a markedly increased severity of BCG infection through mechanisms including increased cytokine

Assessment of sputum smear-positive but culture-negative results among newly diagnosed pulmonary tuberculosis patients in Tanzania

Directory of Open Access Journals (Sweden)

Mnyambwa NP

2017-07-01

Full Text Available Nicholaus Peter Mnyambwa,1,2 Esther S Ngadaya,2 Godfather Kimaro,2 Dong-Jin Kim,1 Rudovick Kazwala,3 Pammla Petrucka,1,4 Sayoki G Mfinanga2 1School of Life Sciences and Bioengineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania; 2National Institute for Medical Research, Muhimbili Medical Research Center, Dar es Salaam, Tanzania; 3Department of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania; 4College of Nursing, University of Saskatchewan, Saskatoon, Canada Abstract: Diagnosis of pulmonary tuberculosis (TB in technology-limited countries is widely achieved by smear microscopy, which has limited sensitivity and specificity. The frequency and clinical implication of smear-positive but culture-negative among presumptive TB patients remains unclear. A cross-sectional substudy was conducted which aimed to identify the proportion of nontuberculous mycobacteria (NTM infections among 94 “smear-positive culture-negative” patients diagnosed between January 2013 and June 2016 in selected health facilities in Tanzania. Out of 94 sputa, 25 (26.60% were GeneXpert® mycobacteria TB positive and 11/94 (11.70% repeat-culture positive; 5 were Capilia TB-Neo positive and confirmed by GenoType MTBC to be Mycobacterium tuberculosis/Mycobacterium canettii. The remaining 6 Capilia TB-Neo negative samples were genotyped by GenoType® CM/AS, identifying 3 (3.19% NTM, 2 Gram positive bacteria, and 1 isolate testing negative, together, making a total of 6/94 (6.38% confirmed false smear-positives. Twenty-eight (29.79% were confirmed TB cases, while 60 (63.83% remained unconfirmed cases. Out of 6 (6.38% patients who were HIV positive, 2 patients were possibly coinfected with mycobacteria. The isolation of NTM and other bacteria among smear-positive culture-negative samples and the presence of over two third of unconfirmed TB cases emphasize the need of both advanced differential TB diagnostic techniques and

Effects of ascent to high altitude on human antimycobacterial immunity.

Directory of Open Access Journals (Sweden)

Sarah Eisen

Full Text Available Tuberculosis infection, disease and mortality are all less common at high than low altitude and ascent to high altitude was historically recommended for treatment. The immunological and mycobacterial mechanisms underlying the association between altitude and tuberculosis are unclear. We studied the effects of altitude on mycobacteria and antimycobacterial immunity.Antimycobacterial immunity was assayed in 15 healthy adults residing at low altitude before and after they ascended to 3400 meters; and in 47 long-term high-altitude residents. Antimycobacterial immunity was assessed as the extent to which participants' whole blood supported or restricted growth of genetically modified luminescent Bacille Calmette-Guérin (BCG mycobacteria during 96 hours incubation. We developed a simplified whole blood assay that could be used by a technician in a low-technology setting. We used this to compare mycobacterial growth in participants' whole blood versus positive-control culture broth and versus negative-control plasma.Measurements of mycobacterial luminescence predicted the number of mycobacterial colonies cultured six weeks later. At low altitude, mycobacteria grew in blood at similar rates to positive-control culture broth whereas ascent to high altitude was associated with restriction (p ≤ 0.002 of mycobacterial growth to be 4-times less than in culture broth. At low altitude, mycobacteria grew in blood 25-times more than negative-control plasma whereas ascent to high altitude was associated with restriction (p ≤ 0.01 of mycobacterial growth to be only 6-times more than in plasma. There was no evidence of differences in antimycobacterial immunity at high altitude between people who had recently ascended to high altitude versus long-term high-altitude residents.An assay of luminescent mycobacterial growth in whole blood was adapted and found to be feasible in low-resource settings. This demonstrated that ascent to or residence at high altitude was

ANAEROBIC BIOLOGICAL TREATMENT OF PRODUCED WATER

Energy Technology Data Exchange (ETDEWEB)

John R. Gallagher

2001-07-31

During the production of oil and gas, large amounts of water are brought to the surface and must be disposed of in an environmentally sensitive manner. This is an especially difficult problem in offshore production facilities where space is a major constraint. The chief regulatory criterion for produced water is oil and grease. Most facilities have little trouble meeting this criterion using conventional oil-water separation technologies. However, some operations have significant amounts of naphthenic acids in the water that behave as oil and grease but are not well removed by conventional technologies. Aerobic biological treatment of naphthenic acids in simulated-produced water has been demonstrated by others; however, the system was easily overloaded by the large amounts of low-molecular-weight organic acids often found in produced waters. The objective of this research was to determine the ability of an anaerobic biological system to treat these organic acids in a simulated produced water and to examine the potential for biodegradation of the naphthenic acids in the anaerobic environment. A small fixed-film anaerobic biological reactor was constructed and adapted to treat a simulated produced water. The bioreactor was tubular, with a low-density porous glass packing material. The inocula to the reactor was sediment from a produced-water holding pond from a municipal anaerobic digester and two salt-loving methanogenic bacteria. During start-up, the feed to the reactor contained glucose as well as typical produced-water components. When glucose was used, rapid gas production was observed. However, when glucose was eliminated and the major organic component was acetate, little gas was generated. Methane production from acetate may have been inhibited by the high salt concentrations, by sulfide, or because of the lack, despite seeding, of microbes capable of converting acetate to methane. Toluene, a minor component of the produced water (0.1 g/L) was removed in the

NM WAIDS: A PRODUCED WATER QUALITY AND INFRASTRUCTURE GIS DATABASE FOR NEW MEXICO OIL PRODUCERS

Energy Technology Data Exchange (ETDEWEB)

Martha Cather; Robert Lee; Ibrahim Gundiler; Andrew Sung; Naomi Davidson; Ajeet Kumar Reddy; Mingzhen Wei

2003-04-01

The New Mexico Water and Infrastructure Data System (NM WAIDS) seeks to alleviate a number of produced water-related issues in southeast New Mexico. The project calls for the design and implementation of a Geographical Information System (GIS) and integral tools that will provide operators and regulators with necessary data and useful information to help them make management and regulatory decisions. The major components of this system are: (1) databases on produced water quality, cultural and groundwater data, oil pipeline and infrastructure data, and corrosion information, (2) a web site capable of displaying produced water and infrastructure data in a GIS or accessing some of the data by text-based queries, (3) a fuzzy logic-based, site risk assessment tool that can be used to assess the seriousness of a spill of produced water, and (4) a corrosion management toolkit that will provide operators with data and information on produced waters that will aid them in deciding how to address corrosion issues. The various parts of NM WAIDS will be integrated into a website with a user-friendly interface that will provide access to previously difficult-to-obtain data and information. Primary attention during the first six months of this project has been focused on creating the water quality databases for produced water and surface water, along with collection of corrosion information and building parts of the corrosion toolkit. Work on the project to date includes: (1) Creation of a water quality database for produced water analyses. The database was compiled from a variety of sources and currently has over 4000 entries for southeast New Mexico. (2) Creation of a web-based data entry system for the water quality database. This system allows a user to view, enter, or edit data from a web page rather than having to directly access the database. (3) Creation of a semi-automated data capturing system for use with standard water quality analysis forms. This system improves the

NM WAIDS: A PRODUCED WATER QUALITY AND INFRASTRUCTURE GIS DATABASE FOR NEW MEXICO OIL PRODUCERS

Energy Technology Data Exchange (ETDEWEB)

Martha Cather; Robert Lee; Ibrahim Gundiler; Andrew Sung

2003-09-24

The New Mexico Water and Infrastructure Data System (NM WAIDS) seeks to alleviate a number of produced water-related issues in southeast New Mexico. The project calls for the design and implementation of a Geographical Information System (GIS) and integral tools that will provide operators and regulators with necessary data and useful information to help them make management and regulatory decisions. The major components of this system are: (1) Databases on produced water quality, cultural and groundwater data, oil pipeline and infrastructure data, and corrosion information. (2) A web site capable of displaying produced water and infrastructure data in a GIS or accessing some of the data by text-based queries. (3) A fuzzy logic-based, site risk assessment tool that can be used to assess the seriousness of a spill of produced water. (4) A corrosion management toolkit that will provide operators with data and information on produced waters that will aid them in deciding how to address corrosion issues. The various parts of NM WAIDS will be integrated into a website with a user-friendly interface that will provide access to previously difficult-to-obtain data and information. Primary attention during the first six months of this project was focused on creating the water quality databases for produced water and surface water, along with collecting of corrosion information and building parts of the corrosion toolkit. Work on the project to date includes: (1) Creation of a water quality database for produced water analyses. The database was compiled from a variety of sources and currently has over 7000 entries for New Mexico. (2) Creation of a web-based data entry system for the water quality database. This system allows a user to view, enter, or edit data from a web page rather than having to directly access the database. (3) Creation of a semi-automated data capturing system for use with standard water quality analysis forms. This system improves the accuracy and speed

Ionising energy treatment for fresh horticultural produce -mandarins and other produce, Trials 1 and 2, May-July 1987

International Nuclear Information System (INIS)

McLauchlan, R.L.; Brown, B.I.; Mitchell, G.E.; Aston, J.W.; Wood, A.F.; Isaacs, A.R.; Williams, S.M.; Nottingham, S.M.; Wilson, P.R.; Juffs, H.S.; Johnson, G.I.; Heather, N.W.; Giles, J.E.; Wills, P.A.

1988-01-01

Two trials are described on the effect of ionising energy treatment, or irradiation, on the quality, shelf-life and composition of fresh produce, mainly at doses consistent with disinfestation treatment for quarantine purposes. Trial 1, carried out in May 1987, deals with replicated treatments of Imperial mandarins and preliminary observation treatments on a range of other produce. Trial 2 deals with replicated treatments of Ellendale mandarins and preliminary observation treatments on other produce

29 CFR 779.108 - Goods produced for commerce.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Goods produced for commerce. 779.108 Section 779.108 Labor... Coverage Employees Engaged in Commerce Or in the Production of Goods for Commerce § 779.108 Goods produced for commerce. Goods are “produced for commerce” if they are “produced, manufactured, mined, handled or...

Bioavailability of isoflavones from soy products in equol producers and non-producers in Japanese women

OpenAIRE

Ayako Miura; Chitose Sugiyama; Hiroyuki Sakakibara; Kayoko Simoi; Toshinao Goda

2016-01-01

Background: The estimated intake of soy isoflavones from a meal has been based on the content in a food, but the health effects of soy isoflavones are possibly affected by their bioavailability. In this study we have evaluated the isoflavone bioavailability after the intake of three kinds of soy foods and a commercial soy isoflavone supplement, and examined whether the isoflavone bioavailability is different between equol producers and non-producers. Methods: Healthy female subjects (n = 2...

Negative regulation by Ser/Thr phosphorylation of HadAB and HadBC dehydratases from Mycobacterium tuberculosis type II fatty acid synthase system.

Science.gov (United States)

Slama, Nawel; Leiba, Jade; Eynard, Nathalie; Daffé, Mamadou; Kremer, Laurent; Quémard, Annaïk; Molle, Virginie

2011-09-02

The type II fatty acid synthase system of mycobacteria is involved in the biosynthesis of major and essential lipids, mycolic acids, key-factors of Mycobacterium tuberculosis pathogenicity. One reason of the remarkable survival ability of M. tuberculosis in infected hosts is partly related to the presence of cell wall-associated mycolic acids. Despite their importance, the mechanisms that modulate synthesis of these lipids in response to environmental changes are unknown. We demonstrate here that HadAB and HadBC dehydratases of this system are phosphorylated by Ser/Thr protein kinases, which negatively affects their enzymatic activity. The phosphorylation of HadAB/BC is growth phase-dependent, suggesting that it represents a mechanism by which mycobacteria might tightly control mycolic acid biosynthesis under non-replicating condition. Copyright © 2011 Elsevier Inc. All rights reserved.

Role Identification and Application of SigD in the Transformation of Soybean Phytosterol to 9α-Hydroxy-4-androstene-3,17-dione in Mycobacterium neoaurum.

Science.gov (United States)

Xiong, Liang-Bin; Liu, Hao-Hao; Xu, Li-Qin; Wei, Dong-Zhi; Wang, Feng-Qing

2017-01-25

9α-Hydroxy-4-androstene-3,17-dione (9-OHAD) is a valuable steroid pharmaceutical intermediate which can be produced by the conversion of soybean phytosterols in mycobacteria. However, the unsatisfactory productivity and conversion efficiency of engineered mycobacterial strains hinder their industrial applications. Here, a sigma factor D (sigD) was investigated due to its dramatic downregulation during the conversion of phytosterols to 9-OHAD. It was determined as a negative regulator in the metabolism of phytosterols, and the deletion of sigD in a 9-OHAD-producing strain significantly enhanced the titer of 9-OHAD by 18.9%. Furthermore, a high yielding strain was constructed by the combined modifications of sigD and choM2, a key gene in the phytosterol metabolism pathway. After the modifications, the productivity of 9-OHAD reached 0.071 g/L/h (10.27 g/L from 20 g/L phytosterol), which was 22.5% higher than the original productivity of 0.058 g/L/h (8.37 g/L from 20 g/L phytosterol) in the industrial resting cell biotransformation system.

7 CFR 1124.13 - Producer milk.

Science.gov (United States)

2010-01-01

... section, Producer milk means the skim milk (or skim milk equivalent of components of skim milk), including... filed a request in writing with the market administrator before the first day of the month the agreement... producer deliveries of each according to a method approved by the market administrator. (4) Diverted milk...

Isolation of biosurfactant producers, optimization and properties of biosurfactant produced by Acinetobacter sp. from petroleum-contaminated soil.

Science.gov (United States)

Chen, J; Huang, P T; Zhang, K Y; Ding, F R

2012-04-01

To screen and identify biosurfactant producers from petroleum-contaminated soil; to use response surface methodology (RSM) for medium optimization to enhance biosurfactant production; and to study the properties of the newly obtained biosurfactant towards pH, temperature and salinity. We successfully isolated three biosurfactant producers from petroleum-contaminated soil and identified them through 16S rRNA sequence analysis, which exhibit the highest similarities to Acinetobacter beijerinckii (100%), Kocuria marina (99%) and Kineococcus marinus (99%), respectively. A quadratic response model was constructed through RSM designs, leading to a 57·5% increase of the growth-associated biosurfactant production by Acinetobacter sp. YC-X 2 with an optimized medium: beef extract 3·12 g l(-1) ; peptone 20·87 g l(-1) ; NaCl 1·04 g l(-1); and n-hexadecane 1·86 g l(-1). Biosurfactant produced by Acinetobacter sp. YC-X 2 retained its properties during exposure to a wide range of pH values (5-11), high temperatures (up to 121°C) and high salinities [up to 18% (w/v) Na(+) and Ca(2+) ], which was more sensitive to Ca(2+) than Na(+). Two novel biosurfactant producers were isolated from petroleum-contaminated soil. Biosurfactant from Acinetobacter sp. YC-X 2 has good properties to a wide range of pH, high temperature and high salinity, and its production was optimized successfully through RSM. The fact, an increasing demand of high-quality surfactants and the lack of cost-competitive bioprocesses of biosurfactants for commercial utilization, motivates researchers to develop cost-effective strategies for biosurfactant production through isolating new biosurfactant producers with special surface-active properties and optimizing their cultural conditions. Two novel biosurfactant producers in this study will widen our knowledge about this kind of micro-organism. This work is the first application of RSM designs for cultural optimization of biosurfactant produced by Acinetobacter

Distribution of the Coenzyme M Pathway of Epoxide Metabolism Among Ethene- and Vinyl Chloride-Degrading Mycobacterium Strains

National Research Council Canada - National Science Library

Coleman, Nicholas

2003-01-01

...) and ethene assimilation pathways of Mycobacterium strain JS6O. In the present study, EaCoMT activity and genes were investigated in 10 different mycobacteria isolated on VC or ethene from diverse environmental samples...

Oilfield Produced Water Reuse and Reinjection with Membrane

Directory of Open Access Journals (Sweden)

Siagian Utjok W.R.

2018-01-01

Full Text Available Produced water has become a global environmental issue due to its huge volume and toxicity that may pose detrimental effects on receiving environment. Several approaches have been proposed to provide a strategy for produced water handling such as reinjection, reuse, or discharge. With various advantages, membrane technology has been increasingly used in produced water treatment replacing the conventional technologies. However, fouling is a major drawback of membrane processes in this application which needs to be controlled. This paper gives an overview and comparison of different produced water management. Special attention is given to produced water treatment for reuse purpose. Furthermore, the use of membrane processes in produced water reuse including performance, challenges, and future outlook are discussed.

Apparatus for producing laser targets

International Nuclear Information System (INIS)

Jarboe, T.R.; Baker, W.R.

1975-01-01

This patent relates to an apparatus and method for producing deuterium targets or pellets of 25u to 75u diameter. The pellets are sliced from a continuously spun solid deuterium thread at a rate of up to 10 pellets/second. The pellets after being sliced from the continuous thread of deuterium are collimated and directed to a point of use, such as a laser activated combustion or explosion chamber wherein the pellets are imploded by laser energy or laser produced target plasmas for neutral beam injection

Sensibilidad in vitro de micobacterias a dos péptidos sintéticos híbridos con actividad antimicrobiana In-vitro activity of two hybrid synthetic peptides having antimicrobial activity against mycobacteria

Directory of Open Access Journals (Sweden)

E. Zerbini

2006-12-01

has been evaluated. The minimal inhibitory concentration was determined by using the broth macrodilution technique. The minimal bactericide concentration in Lowenstein Jensen medium was then obtained. The peptides studied were active, in vitro, against M. smegmatis, but they did not show any activity against the other mycobacteria analyzed.

Pollution Impact and Alternative Treatment for Produced Water

Science.gov (United States)

Hedar, Yusran; Budiyono

2018-02-01

Oil and gas exploration and production are two of the activities that potentially cause pollution and environmental damage. The largest waste generated from this activity is produced water. Produced water contains hazardous pollutants of both organic and inorganic materials, so that the produced water of oil and gas production cannot be discharged directly to the environment. Uncontrolled discharge can lead to the environmental damage, killing the life of water and plants. The produced water needs to be handled and fulfill the quality standards before being discharged to the environment. Several studies to reduce the contaminants in the produced water were conducted by researchers. Among them were gravity based separation - flotation, separation technique based on filtration, and biological process treatment. Therefore, some of these methods can be used as an alternative waste handling of produced water.

Portfolio optimisation for hydropower producers that balances riverine ecosystem protection and producer needs

Science.gov (United States)

Yin, X. A.; Yang, Z. F.; Liu, C. L.

2014-04-01

In deregulated electricity markets, hydropower portfolio design has become an essential task for producers. The previous research on hydropower portfolio optimisation focused mainly on the maximisation of profits but did not take into account riverine ecosystem protection. Although profit maximisation is the major objective for producers in deregulated markets, protection of riverine ecosystems must be incorporated into the process of hydropower portfolio optimisation, especially against a background of increasing attention to environmental protection and stronger opposition to hydropower generation. This research seeks mainly to remind hydropower producers of the requirement of river protection when they design portfolios and help shift portfolio optimisation from economically oriented to ecologically friendly. We establish a framework to determine the optimal portfolio for a hydropower reservoir, accounting for both economic benefits and ecological needs. In this framework, the degree of natural flow regime alteration is adopted as a constraint on hydropower generation to protect riverine ecosystems, and the maximisation of mean annual revenue is set as the optimisation objective. The electricity volumes assigned in different electricity submarkets are optimised by the noisy genetic algorithm. The proposed framework is applied to China's Wangkuai Reservoir to test its effectiveness. The results show that the new framework could help to design eco-friendly portfolios that can ensure a planned profit and reduce alteration of the natural flow regime.

Mycobacterium fortuitum skin infections after subcutaneous injections with Vietnamese traditional medicine: a case report

NARCIS (Netherlands)

Lan, Nguyen Phu Huong; Kolader, Marion-Eliëtte; van Dung, Nguyen; Campbell, James I.; Tham, Nguyen Thi; Chau, Nguyen Van Vinh; van Doorn, H. Rogier; Le, Dien Hoa

2014-01-01

Iatrogenic skin and soft tissue infections by rapidly growing mycobacteria are described with increasing frequency, especially among immunocompromised patients. Here, we present an immunocompetent patient with extensive Mycobacterium fortuitum skin and soft tissue infections after subcutaneous

Music Teacher as Writer and Producer

Science.gov (United States)

Randles, Clint

2012-01-01

In this article I attempt to redefine the role of a music teacher as being more than a director, the more traditional term ascribed to this position. I do this by using descriptions of the role of "writer" and "producer" of student lives borrowed from music education philosophy, screenwriting, and professional music producers. This vision is…

Pollution Impact and Alternative Treatment for Produced Water

Directory of Open Access Journals (Sweden)

Hedar Yusran

2018-01-01

Full Text Available Oil and gas exploration and production are two of the activities that potentially cause pollution and environmental damage. The largest waste generated from this activity is produced water. Produced water contains hazardous pollutants of both organic and inorganic materials, so that the produced water of oil and gas production cannot be discharged directly to the environment. Uncontrolled discharge can lead to the environmental damage, killing the life of water and plants. The produced water needs to be handled and fulfill the quality standards before being discharged to the environment. Several studies to reduce the contaminants in the produced water were conducted by researchers. Among them were gravity based separation - flotation, separation technique based on filtration, and biological process treatment. Therefore, some of these methods can be used as an alternative waste handling of produced water.

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Next? Lung Transplantation Getting on the List Surgery, Recovery, and Life Post-Transplant Waiting for the Transplant ... Clinical Care Guidelines Nontuberculous Mycobacteria Clinical Care Guidelines Nutrition and GI Care Guidelines Antioxidants Clinical Care Guidelines ...

Single-nucleotide variations associated with Mycobacterium ...

Indian Academy of Sciences (India)

or efflux (Li and Nikaido 2005), drug metabolism and drug targets (Blanchard .... including mycobacteria have shown that the level of protein expression depends .... Corbett E, Marston B, Churchyard G and Cock De K 2006. Tuberculosis in ...

Method for producing redox shuttles

Science.gov (United States)

Pupek, Krzysztof Z.; Dzwiniel, Trevor L.; Krumdick, Gregory K.

2015-03-03

A single step method for producing a redox shuttle having the formula 2,5-di-tert-butyl-1,4-phenylene tetraethyl bis(phosphate) is provided, the method comprising phosphorylating tert butyl hydroquinone with a phosphate-containing reagent. Also provided is method for producing 2,5-di-tert-butyl-1,4-phenylene tetraethyl bis(phosphate), the method comprising solubilizing tert-butyl hydroquinone and tetrabutylammonium bromide with methyltetrahydrofuran to create a mixture; heating the mixture while adding base to the mixture in an amount to turn the mixture orange; and adding diethyl chlorophosphate to the orange mixture in an amount to phosphorylate the hydroquinone.

Characterization of bacteriocin produced by Lactobacillus plantarum ...

African Journals Online (AJOL)

Characterization of bacteriocin produced by Lactobacillus plantarum F1 and ... brevis OG1 isolated from Nigerian fermented food products, produced bacteriocins ... interest for food safety and may have future applications as food preservative.

Genetic engineering of to produce Bacterial Polyhydroxyalkanotes ...

African Journals Online (AJOL)

PHAs), in the sense of an environmental precaution appears meaningful and necessary. In order to more economically produce microbial products, this investigation was focused on suitable producers, like the yeast Schizosaccharomyces pombe ...

[Follow-up on an outbreak in Venezuela of soft-tissue infection due to Mycobacterium abscessus associated with Mesotherapy].

Science.gov (United States)

Da Mata Jardín, Omaira; Hernández-Pérez, Rolando; Corrales, Haideé; Cardoso-Leao, Sylvia; de Waard, Jacobus H

2010-11-01

Skin and soft tissue infections caused by nontuberculous mycobacteria (NMT) are reported to be associated with injections, liposuction, plastic surgery, and acupuncture. Herein, we describe an outbreak of soft tissue infection due to NMT following mesotherapy, a cosmetic procedure involving injection of poorly defined mixtures alleged to reduce local adiposity. Patients with skin lesions and a history of mesotherapy treatment, who visited the dermatology department of the public hospital in Barinas, Venezuela, from November 2004 to February 2005 were interviewed. Clinical and environmental samples were taken for mycobacteria isolation. The interviews revealed that 68 patients who had been treated for cosmetic purposes at the same clinic by the same therapist had received injections with the same product and were infected with NMT. Clinical specimens from 5 patients grew Mycobacterium abscessus. No mesotherapy solution was available for analysis but M. abscessus was isolated from an environmental sample in the clinic. PCR-based strain typing techniques (ERIC-PCR, BOXA1R and RAPD) showed that the patient's isolates were undistinguishable from each other but different from the environmental isolate. This outbreak was likely caused by a contaminated injectable mesotherapy product and not by mycobacteria from the clinic environment. We emphasize the importance of better microbiological control of these products. To our knowledge, this outbreak, which affected at least 68 patients, appears to be the largest ever associated with mesotherapy and described in the literature. Copyright © 2009 Elsevier España, S.L. All rights reserved.

Identification and characterization of a spore-like morphotype in chronically starved Mycobacterium avium subsp. paratuberculosis cultures.

Directory of Open Access Journals (Sweden)

Elise A Lamont

Full Text Available Mycobacteria are able to enter into a state of non-replication or dormancy, which may result in their chronic persistence in soil, aquatic environments, and permissive hosts. Stresses such as nutrient deprivation and hypoxia provide environmental cues to enter a persistent state; however, a clear definition of the mechanism that mycobacteria employ to achieve this remains elusive. While the concept of sporulation in mycobacteria is not novel, it continues to spark controversy and challenges our perceptions of a non-replication. We investigated the potential role of sporulation in one-year old broth cultures of Mycobacterium subsp. paratuberculosis (MAP. We show that dormant cultures of MAP contain a mix of vegetative cells and a previously unknown morphotype resembling a spore. These spore-like structures can be enriched for using sporulating media. Furthermore, purified MAP spore forms survive exposure to heat, lysozyme and proteinase K. Heat-treated spores are positive for MAP 16SrRNA and IS900. MAP spores display enhanced infectivity as well as maintain acid-fast characteristics upon germination in a well-established bovine macrophage model. This is the first study to demonstrate a new MAP morphotype possessing spore-like qualities. Data suggest that sporulation may be a viable mechanism by which MAP accomplishes persistence in the host and/or environment. Thus, our current understanding of mycobacterial persistence, pathogenesis, epidemiology and rational drug and vaccine design may need to be reevaluated.

Mycobacterium canettii Infection of Adipose Tissues.

Science.gov (United States)

Bouzid, Fériel; Brégeon, Fabienne; Poncin, Isabelle; Weber, Pascal; Drancourt, Michel; Canaan, Stéphane

2017-01-01

Adipose tissues were shown to host Mycobacterium tuberculosis which is persisting inside mature adipocytes. It remains unknown whether this holds true for Mycobacterium canettii , a rare representative of the M. tuberculosis complex responsible for lymphatic and pulmonary tuberculosis. Here, we infected primary murine white and brown pre-adipocytes and murine 3T3-L1 pre-adipocytes and mature adipocytes with M. canettii and M. tuberculosis as a positive control. Both mycobacteria were able to infect 18-22% of challenged primary murine pre-adipocytes; and to replicate within these cells during a 7-day experiment with the intracellular inoculums being significantly higher in brown than in white pre-adipocytes for M. canettii ( p = 0.02) and M. tuberculosis ( p = 0.03). Further in-vitro infection of 3T3-L1 mature adipocytes yielded 9% of infected cells by M. canettii and 17% of infected cells by M. tuberculosis ( p = 0.001). Interestingly, M. canettii replicated and accumulated intra-cytosolic lipid inclusions within mature adipocytes over a 12-day experiment; while M. tuberculosis stopped replicating at day 3 post-infection. These results indicate that brown pre-adipocytes could be one of the potential targets for M. tuberculosis complex mycobacteria; and illustrate differential outcome of M. tuberculosis complex mycobacteria into adipose tissues. While white adipose tissue is an unlikely sanctuary for M. canettii , it is still an open question whether M. canettii and M. tuberculosis could persist in brown adipose tissues.

Disconfirmed hedonic expectations produce perceptual contrast, not assimilation.

Science.gov (United States)

Zellner, Debra A; Strickhouser, Dinah; Tornow, Carina E

2004-01-01

In studies of hedonic ratings, contrast is the usual result when expectations about test stimuli are produced through the presentation of context stimuli, whereas assimilation is the usual result when expectations about test stimuli are produced through labeling, advertising, or the relaying of information to the subject about the test stimuli. Both procedures produce expectations that are subsequently violated, but the outcomes are different. The present studies demonstrate that both assimilation and contrast can occur even when expectations are produced by verbal labels and the degree of violation of the expectation is held constant. One factor determining whether assimilation or contrast occurs appears to be the certainty of the expectation. Expectations that convey certainty are produced by methods that lead to social influence on subjects' ratings, producing assimilation. When social influence is not a factor and subjects give judgments influenced only by the perceived hedonic value of the stimulus, contrast is the result.

Effects of treatment on free radicals in patients with pulmonary ...

African Journals Online (AJOL)

fense against Mycobacteria, enhanced ROS generation may promote tissue injury .... time of analysis for electrolytes and free radicals. The sputum of patients .... with high level INH resistance in MTB by using real time technology PCR with 3 ...

A Mycobacterium avium subsp. paratuberculosis predicted serine protease is associated with acid stress and intraphagosomal survival

Science.gov (United States)

Mycobacterium avium subsp. paratuberculosis (MAP) is an intracellular pathogen that persists inside host macrophages despite severe oxidative stress and nutrient deprivation. Intrabacterial pH homeostasis is vital to pathogenic mycobacteria to preserve cellular biological processes and stability of ...

Katoch, Dr Vishwa Mohan

Indian Academy of Sciences (India)

Specialization: Molecular Biology and Functional Genomics of Mycobacteria, Taxonomy, Epidemiology of Mycobacterial Diseases Address: Secretary, Department of Health Research and, Director General, Indian Council of Medical Research, Ramalingaswami Bhavan, Ansari Nagar, New Delhi 110 029, U.T.. Contact:

Draft Genome Sequences of Six Mycobacterium immunogenum, Strains Obtained from a Chloraminated Drinking Water Distribution System Simulator

Science.gov (United States)

We report the draft genome sequences of six Mycobacterium immunogenum isolated from a chloraminated drinking water distribution system simulator subjected to changes in operational parameters. M. immunogenum, a rapidly growing mycobacteria previously reported as the cause of hyp...

A method of producing a body comprising porous alpha silicon carbide and the body produced by the method

DEFF Research Database (Denmark)

2017-01-01

The present invention relates to a method of producing porous alpha-SiC containing shaped body and porous alpha-SiC containing shaped body produced by that method. The porous alpha-SiC containing shaped body shows a characteristic microstructure providing a high degree of mechanical stability...

Producing x-rays

International Nuclear Information System (INIS)

Mallozzi, P.J.; Epstein, H.M.; Jung, R.G.; Applebaum, D.C.; Fairand, B.P.; Gallagher, W.J.

1977-01-01

A method of producing x-rays by directing radiant energy from a laser onto a target is described. Conversion efficiency of at least about 3 percent is obtained by providing the radiant energy in a low-power precursor pulse of approximately uniform effective intensity focused onto the surface of the target for about 1 to 30 nanoseconds so as to generate an expanding unconfined coronal plasma having less than normal solid density throughout and comprising a low-density (underdense) region wherein the plasma frequency is less than the laser radiation frequency and a higher-density (overdense) region wherein the plasma frequency is greater than the laser radiation frequency and, about 1 to 30 nanoseconds after the precursor pulse strikes the target, a higher-power main pulse focused onto the plasma for about 10 -3 to 30 nanoseconds and having such power density and total energy that the radiant energy is absorbed in the underdense region and conducted into the overdense region to heat it and thus to produce x-rays therefrom with the plasma remaining substantially below normal solid density and thus facilitating the substantial emission of x-rays in the form of spectral lines arising from nonequilibrium ionization states

Characterization of beryllium foil produced by hot rolling

International Nuclear Information System (INIS)

Wittenauer, J.; Nieh, T.G.; Waychunas, G.

1992-01-01

Beryllium foil is important for a number of aerospace applications including honeycomb structures and metal-matrix composites. In this study, a method of producing beryllium foil directly from powder or flake is demonstrated. A variety of foils were produced in the thickness range 90-300 μm, free from defects such as pinholes and excessive surface roughness, and exhibiting sufficient formability for honeycomb manufacture. Foil produced directly from powder or flake exhibits crystallographic texture, microstructure, and formability equivalent to foil produced from more massive precursors. (Author)

Decomposition analysis of CO2 emission intensity between oil-producing and non-oil-producing sub-Saharan African countries

International Nuclear Information System (INIS)

Ebohon, Obas John; Ikeme, Anthony Jekwu

2006-01-01

The need to decompose CO 2 emission intensity is predicated upon the need for effective climate change mitigation and adaptation policies. Such analysis enables key variables that instigate CO 2 emission intensity to be identified while at the same time providing opportunities to verify the mitigation and adaptation capacities of countries. However, most CO 2 decomposition analysis has been conducted for the developed economies and little attention has been paid to sub-Saharan Africa. The need for such an analysis for SSA is overwhelming for several reasons. Firstly, the region is amongst the most vulnerable to climate change. Secondly, there are disparities in the amount and composition of energy consumption and the levels of economic growth and development in the region. Thus, a decomposition analysis of CO 2 emission intensity for SSA affords the opportunity to identify key influencing variables and to see how they compare among countries in the region. Also, attempts have been made to distinguish between oil and non-oil-producing SSA countries. To this effect a comparative static analysis of CO 2 emission intensity for oil-producing and non oil-producing SSA countries for the periods 1971-1998 has been undertaken, using the refined Laspeyres decomposition model. Our analysis confirms the findings for other regions that CO 2 emission intensity is attributable to energy consumption intensity, CO 2 emission coefficient of energy types and economic structure. Particularly, CO 2 emission coefficient of energy use was found to exercise the most influence on CO 2 emission intensity for both oil and non-oil-producing sub-Saharan African countries in the first sub-interval period of our investigation from 1971-1981. In the second subinterval of 1981-1991, energy intensity and structural effect were the two major influencing factors on emission intensity for the two groups of countries. However, energy intensity effect had the most pronounced impact on CO 2 emission

AFSC/REFM: Bomb-produced age validation study

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Fish age validation with bomb-produced radiocarbon (14C) requires a known-age Delta14C reference chronology spanning the era of a marine increase in bomb-produced...

Utility and diagnostic performance of Mycobacterium tuberculosis complex by two immunochromatographic assays as compared with the molecular Genotype assay in Nigeria

Directory of Open Access Journals (Sweden)

Benjamin Thumamo Pokam

2013-01-01

Full Text Available Among the disadvantages of smear microscopy for detection of tuberculosis cases is its inability to differentiate between Mycobacterium tuberculosis (MTB and non-tuberculous mycobacteria (NTM. This study evaluated two, new immunochromatographic assays – Capilia TB-Neo and SD Bioline – on unheated and heated cultures at 80 °C for 30 min respectively for their ability to discriminate between MTB complex and NTM as compared with the molecular Genotype assay. Mycobacteria used in the study were obtained from smear-positive specimens collected from patients at four major hospitals in Cross River State, Nigeria. Capilia TB-Neo and SD Bioline showed sensitivities of 98.8% and 93.8% respectively and 100% specificity for both assays. Heating the isolates did not significantly impact the test performance. Both tests are recommended for use in rapid differentiation of strains isolated in Nigeria.

An inducible expression system for high-level expression of recombinant proteins in slow growing mycobacteria.

Science.gov (United States)

Leotta, Lisa; Spratt, Joanne M; Kong, Carlyn U; Triccas, James A

2015-09-01

A novel protein expression vector utilising the inducible hspX promoter of Mycobacterium tuberculosis was constructed and evaluated in this study. High-level induction of three mycobacterial antigens, comprising up to 9% of bacterial sonicate, was demonstrated in recombinant Mycobacterium bovis BCG when grown under low-oxygen tension, which serves to enhance hspX promoter activity. Recombinant proteins were efficiently purified from bacterial lysates in a soluble form by virtue of a C-terminal 6-histidine tag. Purification of the immunodominant M. tuberculosis Ag85B antigen using this system resulted in a recombinant protein that stimulated significant IFN-γ release from Ag85B-reactive T cells generated after vaccination of mice with an Ag85B-expressing vaccine. Further, the M. tuberculosis L-alanine dehydrogenase (Ald) protein purified from recombinant BCG displayed strong enzymatic activity in recombinant form. This study demonstrated that high levels of native-like recombinant mycobacterial proteins can be produced in mycobacterial hosts, and this may aid the analysis of mycobacterial protein function and the development of new treatments. Copyright © 2015 Elsevier B.V. All rights reserved.

Can student-produced video transform university teaching?

DEFF Research Database (Denmark)

2011-01-01

as preparation for the two week intensive field course. The overall objective of the redesign was to modernize and improve the quality of the students learning experience, by exploring the potentials of video and online tools to create flexible, student-centered and student-activating education. The student...... produced three types of videos during the course: Video 1 was independently produced by the students, guided by online tasks and instructions. These videos were student produced learning material, showing cases from all over Europe. The videos was collected and presented in a "visual database" in Google...

Method for producing uranium atomic beam source

International Nuclear Information System (INIS)

Krikorian, O.H.

1976-01-01

A method is described for producing a beam of neutral uranium atoms by vaporizing uranium from a compound UM/sub x/ heated to produce U vapor from an M boat or from some other suitable refractory container such as a tungsten boat, where M is a metal whose vapor pressure is negligible compared with that of uranium at the vaporization temperature. The compound, for example, may be the uranium-rhenium compound, URe 2 . An evaporation rate in excess of about 10 times that of conventional uranium beam sources is produced

7 CFR 46.22 - Accounting for dumped produce.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Accounting for dumped produce. 46.22 Section 46.22... Market Receivers § 46.22 Accounting for dumped produce. A clear and complete record shall be maintained..., shall be obtained to prove the produce was actually without commercial value, unless there is a specific...

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... CF Working With Your Care Team Fitness and Nutrition Fitness Nutrition and Your Digestive System Germs and Staying Healthy ... Clinical Care Guidelines Nontuberculous Mycobacteria Clinical Care Guidelines Nutrition and GI Care Guidelines Antioxidants Clinical Care Guidelines ...

GENETIC FINGERPRINTING OF MYCOBACTERIUM AVIUM COMPLEX (MAC) ORGANISMS ISOLATED FROM HOSPITAL PATIENTS AND THE ENVIRONMENT

Science.gov (United States)

A particularly pathogenic group of mycobacteria belong to the Mycobacterium avium complex (MAC), which includes M. avium and M. intracellulare. MAC organisms cause disease in children, the elderly, and immuno-compromised individuals. A critical step in preventing MAC infections...

Multinucleated giant cell cytokine expression in pulmonary granulomas of cattle experimentally infected with Mycobacterium bovis

Science.gov (United States)

Pathogenic mycobacteria of the Mycobacterium tuberculosis complex such as Mycobacterium bovis, induce a characteristic lesion known as a granulomas. Granulomas represent a specific host response to chronic antigenic stimuli, such as foreign bodies, certain bacterial components, or persistent pathoge...

Emergence and spread of a human-transmissible multidrug-resistant nontuberculous mycobacterium

DEFF Research Database (Denmark)

Bryant, Josephine M; Grogono, Dorothy M; Rodriguez-Rincon, Daniela

2016-01-01

Lung infections with Mycobacterium abscessus, a species of multidrug-resistant nontuberculous mycobacteria, are emerging as an important global threat to individuals with cystic fibrosis (CF), in whom M. abscessus accelerates inflammatory lung damage, leading to increased morbidity and mortality....

Automatic produce quality monitoring in Reefer containers

NARCIS (Netherlands)

Lukasse, L.J.S.; Sanders, M.G.; Kramer, de J.E.

2003-01-01

Current day perishable supply chains require intermediate points for manual produce quality inspection. Over the last decade international seatransport of fruit and vegetables in reefer containers has grown tremendously. Reefer containers may completely close the cold chain only if produce quality

Characterization of Soluble Organics in Produced Water

Energy Technology Data Exchange (ETDEWEB)

Bostick, D.T.

2002-01-16

Soluble organics in produced water and refinery effluents represent treatment problems for the petroleum industry. Neither the chemistry involved in the production of soluble organics nor the impact of these chemicals on total effluent toxicity is well understood. The U.S. Department of Energy provides funding for Oak Ridge National Laboratory (ORNL) to support a collaborative project with Shell, Chevron, Phillips, and Statoil entitled ''Petroleum and Environmental Research Forum project (PERF 9844: Manage Water-Soluble Organics in Produced Water''). The goal of this project, which involves characterization and evaluation of these water-soluble compounds, is aimed at reducing the future production of such contaminants. To determine the effect that various drilling conditions might have on water-soluble organics (WSO) content in produced water, a simulated brine water containing the principal inorganic components normally found in Gulf of Mexico (GOM) brine sources was prepared. The GOM simulant was then contacted with as-received crude oil from a deep well site to study the effects of water cut, produced-water pH, salinity, pressure, temperature, and crude oil sources on the type and content of the WSO in produced water. The identities of individual semivolatile organic compounds (SVOCs) were determined in all as-received crude and actual produced water samples using standard USEPA Method (8270C) protocol. These analyses were supplemented with the more general measurements of total petroleum hydrocarbon (TPH) content in the gas (C{sub 6}-C{sub 10}), diesel (C{sub 10}-C{sub 20}), and oil (C{sub 20}-C{sub 28}) carbon ranges as determined by both gas chromatographic (GC) and infrared (IR) analyses. An open liquid chromatographic procedure was also used to differentiate the saturated hydrocarbon, aromatic hydrocarbon, and polar components within the extractable TPH. Inorganic constituents in the produced water were analyzed by ion

Virus-like particle of Macrobrachium rosenbergii nodavirus produced in Spodoptera frugiperda (Sf9) cells is distinctive from that produced in Escherichia coli.

Science.gov (United States)

Kueh, Chare Li; Yong, Chean Yeah; Masoomi Dezfooli, Seyedehsara; Bhassu, Subha; Tan, Soon Guan; Tan, Wen Siang

2017-03-01

Macrobrachium rosenbergii nodavirus (MrNV) is a virus native to giant freshwater prawn. Recombinant MrNV capsid protein has been produced in Escherichia coli, which self-assembled into virus-like particles (VLPs). However, this recombinant protein is unstable, degrading and forming heterogenous VLPs. In this study, MrNV capsid protein was produced in insect Spodoptera frugiperda (Sf9) cells through a baculovirus system. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) revealed that the recombinant protein produced by the insect cells self-assembled into highly stable, homogenous VLPs each of approximately 40 nm in diameter. Enzyme-linked immunosorbent assay (ELISA) showed that the VLPs produced in Sf9 cells were highly antigenic and comparable to those produced in E. coli. In addition, the Sf9 produced VLPs were highly stable across a wide pH range (2-12). Interestingly, the Sf9 produced VLPs contained DNA of approximately 48 kilo base pairs and RNA molecules. This study is the first report on the production and characterization of MrNV VLPs produced in a eukaryotic system. The MrNV VLPs produced in Sf9 cells were about 10 nm bigger and had a uniform morphology compared with the VLPs produced in E. coli. The insect cell production system provides a good source of MrNV VLPs for structural and immunological studies as well as for host-pathogen interaction studies. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:549-557, 2017. © 2016 American Institute of Chemical Engineers.

Producing and marketing a specialty egg.

Science.gov (United States)

Michella, S M; Slaugh, B T

2000-07-01

Eggland's Best, Inc. markets premium quality shell eggs under the Eggland's Best (EB) brand name. The company, started in 1988, is comprised of a franchise network of established egg producers and covers most of the United States. Eggland's Best provides its franchisees with marketing and technical support. The franchisees produce, process, and distribute EB eggs according to the strict program established and monitored by EB. Production follows the all-natural vegetarian feed program in accordance with the company's US patent entitled "Eggs Compatible with a Cholesterol Reducing Diet and Method of Producing the Same." The EB program excludes animal fat and other animal byproducts. Eggland's Best eggs have seven times the generic level of vitamin E, nearly three times more omega-3 fatty acids and iodine, and 25% less saturated fat than regular generic eggs. Eggland's Best has one of the finest shell egg quality assurance programs anywhere. Eggland's Best franchisees submit weekly egg samples that are analyzed for shell quality, interior quality, vitamin E, iodine, cholesterol and fatty acids. Samples of feed and the EB-patented feed supplement are also analyzed. Approximately 28,000 total laboratory tests are conducted annually. Nationwide product and display retail evaluations are contracted through an outside audit company (40 to 50 cities evaluated four times per year). All EB eggs are USDA graded according to EB's strict quality standards. Producers must follow a food safety quality assurance program (United Egg Producers Association 5-Star or equivalent state or company program). Each egg is stamped "EB" as assurance of meeting EB's highest standards of flavor, quality, and nutrition. Eggland's Best has enjoyed record sales growth for the past 3 yr.

7 CFR 932.129 - Nomination procedures for producer members.

Science.gov (United States)

2010-01-01

... choose the district in which the producer will vote and notify the Committee of that choice. If the... producer wishes to participate shall be the producer's choice. (4) Any member of a producer's family (husband, wife, son or daughter) may vote on behalf of an owner-operated, landlord-tenant, family...

Standards and producers' liability

International Nuclear Information System (INIS)

Kretschmer, F.

1979-01-01

The author discusses the liability of producers and the diligence required, which has to come up to technical standards and the latest state of technology. The consequences of this requirement with regard to claims for damages are outlined and proposals for reforms are pointed out. (HSCH) [de

Comparative Proteome Analysis between High Lipid-Producing Strain Mucor circinelloides WJ11 and Low Lipid-Producing Strain CBS 277.49.

Science.gov (United States)

Tang, Xin; Chen, Haiqin; Gu, Zhennan; Zhang, Hao; Chen, Yong Q; Song, Yuanda; Chen, Wei

2017-06-21

Mucor circinelloides is one of few oleaginous fungi that produces a useful oil rich in γ-linolenic acid, but it usually only produces <25% total lipid. Nevertheless, we isolated a new strain WJ11 that can produce up to 36% lipid of cell dry weight. In this study, we have systematically analyzed the global changes in protein levels between the high lipid-producing strain WJ11 and the low lipid-producing strain CBS 277.49 (15%, lipid/cell dry weight) at lipid accumulation phase through comparative proteome analysis. Proteome analysis demonstrated that the branched-chain amino acid and lysine metabolism, glycolytic pathway, and pentose phosphate pathway in WJ11 were up-regulated, while the activities of tricarboxylic acid cycle and branch point enzyme for synthesis of isoprenoids were retarded compared with CBS 277.49. The coordinated regulation at proteome level indicate that more acetyl-CoA and NADPH are provided for fatty acid biosynthesis in WJ11 compared with CBS 277.49.

ESBL-Producing Escherichia coli

DEFF Research Database (Denmark)

Hertz, Frederik Boetius

Urinary tract infection (UTI) is one the most common bacterial infections and is regularly treated in primary health care. The most common cause of UTI is extraintestinal pathogenic Escherichia coli (ExPEC) already present in the intestinal microflora, often as the dominating strain. Resistance...... in E.coli is increasing and especially isolates producing Extended-Spectrum Beta-Lactamases (ESBL) have been reported worldwide. Treatment of UTI is usually initiated by the general practitioners and a significant proportion of clinical isolates are now resistant to first line antibiotics. The global...... to investigate (i) antibiotics involved in selection of ESBL-producing E.coli, in an experimental mouse model in vivo, (ii) risk factors for UTI with ESBL-producing E.coli and (iii) to describe the phylogenetic composition of E.coli populations with different resistance patterns. We found that different...

Potential biosurfactant producing endophytic and epiphytic fungi ...

African Journals Online (AJOL)

Potential biosurfactant producing endophytic and epiphytic fungi, isolated from macrophytes in the Negro River in Manaus, Amazonas, Brazil. ... Solms and Cyperus ligularis L., macrophytes collected from oil-contaminated waters, were studied to assess their potential for producing biosurfactants; the most promising ones ...

Does Bt Corn Really Produce Tougher Residues

Science.gov (United States)

Bt corn hybrids produce insecticidal proteins that are derived from a bacterium, Bacillus thuringiensis. There have been concerns that Bt corn hybrids produce residues that are relatively resistant to decomposition. We conducted four experiments that examined the decomposition of corn residues und...

77 FR 9888 - Shiga Toxin-Producing Escherichia coli

Science.gov (United States)

2012-02-21

... Toxin-Producing Escherichia coli in Certain Raw Beef Products AGENCY: Food Safety and Inspection Service... toxin-producing Escherichia coli (STEC) serogroups (O26, O45, O103, O111, O121, and O145). This new date..., that are contaminated with Shiga toxin-producing Escherichia coli (STEC) O26, O45, O103, O111, O121...

Produced water radionuclide hazard/risk assessment, Phase 1

Energy Technology Data Exchange (ETDEWEB)

Hamilton, L.D.; Meinhold, A.F.; Nagy, J.

1991-06-01

Petroleum production may be accompanied by the production of saline water, called produced water.'' Produced water discharged into freshwater streams, estuaries, coastal and outer continental shelf waters can contained enhanced levels of radium isotopes. This document reports on the first phase of a study to estimate the risk to human health and the environment from radium discharged in produced water. The study involved five major steps: (1) evaluate the usefulness of available produced water outfall data for developing estimates of radium environmental concentrations; (2) review the literature on the bioaccumulation of radium by aquatic organism; (3) review the literature on the effects of radiation on aquatic organisms; (4) review the information available concerning the human health risks associated with exposure to Ra-226 and Ra-228 and (5) perform a conservative, screening-level assessment of the health and environmental risks posed by Ra-226 and Ra-228 discharged in produced waters. A screening-level analysis was performed to determine whether radium discharged to coastal Louisiana in produced waters presents potential health or environmental risks requiring further study. This conservative assessment suggested that no detectable impact on populations of fish, molluscs or crustaceans from radium discharged in produced waters is likely. The analysis also suggested that there is a potential for risk were an individual to ingest a large amount of seafood harvested near a produced water discharge point over a lifetime. The number of excess cancers predicted per year under a conservative scenario is comparable to those expected to result from background concentrations of radium.

Produced water radionuclide hazard/risk assessment, Phase 1

Energy Technology Data Exchange (ETDEWEB)

Hamilton, L.D.; Meinhold, A.F.; Nagy, J.

1991-06-01

Petroleum production may be accompanied by the production of saline water, called ``produced water.`` Produced water discharged into freshwater streams, estuaries, coastal and outer continental shelf waters can contained enhanced levels of radium isotopes. This document reports on the first phase of a study to estimate the risk to human health and the environment from radium discharged in produced water. The study involved five major steps: (1) evaluate the usefulness of available produced water outfall data for developing estimates of radium environmental concentrations; (2) review the literature on the bioaccumulation of radium by aquatic organism; (3) review the literature on the effects of radiation on aquatic organisms; (4) review the information available concerning the human health risks associated with exposure to Ra-226 and Ra-228 and (5) perform a conservative, screening-level assessment of the health and environmental risks posed by Ra-226 and Ra-228 discharged in produced waters. A screening-level analysis was performed to determine whether radium discharged to coastal Louisiana in produced waters presents potential health or environmental risks requiring further study. This conservative assessment suggested that no detectable impact on populations of fish, molluscs or crustaceans from radium discharged in produced waters is likely. The analysis also suggested that there is a potential for risk were an individual to ingest a large amount of seafood harvested near a produced water discharge point over a lifetime. The number of excess cancers predicted per year under a conservative scenario is comparable to those expected to result from background concentrations of radium.

Produced water radionuclide hazard/risk assessment, Phase 1

International Nuclear Information System (INIS)

Hamilton, L.D.; Meinhold, A.F.; Nagy, J.

1991-06-01

Petroleum production may be accompanied by the production of saline water, called ''produced water.'' Produced water discharged into freshwater streams, estuaries, coastal and outer continental shelf waters can contained enhanced levels of radium isotopes. This document reports on the first phase of a study to estimate the risk to human health and the environment from radium discharged in produced water. The study involved five major steps: (1) evaluate the usefulness of available produced water outfall data for developing estimates of radium environmental concentrations; (2) review the literature on the bioaccumulation of radium by aquatic organism; (3) review the literature on the effects of radiation on aquatic organisms; (4) review the information available concerning the human health risks associated with exposure to Ra-226 and Ra-228 and (5) perform a conservative, screening-level assessment of the health and environmental risks posed by Ra-226 and Ra-228 discharged in produced waters. A screening-level analysis was performed to determine whether radium discharged to coastal Louisiana in produced waters presents potential health or environmental risks requiring further study. This conservative assessment suggested that no detectable impact on populations of fish, molluscs or crustaceans from radium discharged in produced waters is likely. The analysis also suggested that there is a potential for risk were an individual to ingest a large amount of seafood harvested near a produced water discharge point over a lifetime. The number of excess cancers predicted per year under a conservative scenario is comparable to those expected to result from background concentrations of radium

Methods of producing compounds from plant materials

Science.gov (United States)

Werpy, Todd A [West Richland, WA; Schmidt, Andrew J [Richland, WA; Frye, Jr., John G.; Zacher, Alan H. , Franz; James A. , Alnajjar; Mikhail S. , Neuenschwander; Gary G. , Alderson; Eric V. , Orth; Rick J. , Abbas; Charles A. , Beery; Kyle E. , Rammelsberg; Anne M. , Kim; Catherine, J [Decatur, IL

2010-01-26

The invention includes methods of processing plant material by adding water to form a mixture, heating the mixture, and separating a liquid component from a solid-comprising component. At least one of the liquid component and the solid-comprising component undergoes additional processing. Processing of the solid-comprising component produces oils, and processing of the liquid component produces one or more of glycerol, ethylene glycol, lactic acid and propylene glycol. The invention includes a process of forming glycerol, ethylene glycol, lactic acid and propylene glycol from plant matter by adding water, heating and filtering the plant matter. The filtrate containing starch, starch fragments, hemicellulose and fragments of hemicellulose is treated to form linear poly-alcohols which are then cleaved to produce one or more of glycerol, ethylene glycol, lactic acid and propylene glycol. The invention also includes a method of producing free and/or complexed sterols and stanols from plant material.

Methods of producing compounds from plant material

Energy Technology Data Exchange (ETDEWEB)

Werpy, Todd A.; Schmidt, Andrew J.; Frye, Jr., John G.; Zacher, Alan H.; Franz, James A.; Alnajjar, Mikhail S.; Neuenschwander, Gary G.; Alderson, Eric V.; Orth, Rick J.; Abbas, Charles A.; Beery, Kyle E.; Rammelsberg, Anne M.; Kim, Catherine J.

2006-01-03

The invention includes methods of processing plant material by adding water to form a mixture, heating the mixture, and separating a liquid component from a solid-comprising component. At least one of the liquid component and the solid-comprising component undergoes additional processing. Processing of the solid-comprising component produces oils, and processing of the liquid component produces one or more of glycerol, ethylene glycol, lactic acid and propylene glycol. The invention includes a process of forming glycerol, ethylene glycol, lactic acid and propylene glycol from plant matter by adding water, heating and filtering the plant matter. The filtrate containing starch, starch fragments, hemicellulose and fragments of hemicellulose is treated to form linear poly-alcohols which are then cleaved to produce one or more of glycerol, ethylene glycol, lactic acid and propylene glycol. The invention also includes a method of producing free and/or complexed sterols and stanols from plant material.

Environmental aspects of produced-water salt releases in onshore and coastal petroleum-producing areas of the conterminous U.S. - a bibliography

Science.gov (United States)

Otton, James K.

2006-01-01

Environmental effects associated with the production of oil and gas have been reported since the first oil wells were drilled in the Appalachian Basin in Pennsylvania and Kentucky in the early to mid-1800s. The most significant of these effects are the degradation of soils, ground water, surface water, and ecosystems they support by releases of suspended and dissolved hydrocarbons and co-produced saline water. Produced water salts are less likely than hydrocarbons to be adsorbed by mineral phases in the soil and sediment and are not subject to degradation by biologic processes. Sodium is a major dissolved constituent in most produced waters and it causes substantial degradation of soils through altering of clays and soil textures and subsequent erosion. Produced water salts seem to have the most wide-ranging effects on soils, water quality, and ecosystems. Trace elements, including boron, lithium, bromine, fluorine, and radium, also occur in elevated concentrations in some produced waters. Many trace elements are phytotoxic and are adsorbed and may remain in soils after the saline water has been flushed away. Radium-bearing scale and sludge found in oilfield equipment and discarded on soils pose additional hazards to human health and ecosystems. This bibliography includes studies from across the oil- and natural-gas-producing areas of the conterminous United States that were published in the last 80 yrs. The studies describe the effects of produced water salts on soils, water quality, and ecosystems. Also included are reports that describe (1) the inorganic chemistry of produced waters included in studies of formation waters for various purposes, (2) other sources of salt affecting water quality that may be mistaken for produced water effects, (3) geochemical and geophysical techniques that allow discrimination of salt sources, (4) remediation technologies designed to repair damage caused to soils and ground water by produced water salts, and (5) contamination by

Study on Laser Induced Plasma Produced in Liquid

International Nuclear Information System (INIS)

Tsuda, N.; Yamada, J.

2003-01-01

When an intense laser light is focused in liquid, a hot plasma is produced at the focal spot. The breakdown threshold and the transmittance of sodium choroids solution are observed using excimer laser or YAG laser. The breakdown threshold decreases with increasing NaCl concentration. Threshold intensity of plasma produced by YAG laser is lower than excimer laser. The behavior of plasma development is observed by a streak camera. The plasma produced by a YAG laser develops only backward. However, the plasma produced by excimer laser develops not only backward but also forward same as the plasma development in high-pressure gases

Exposure of Monocytes to Lipoarabinomannan Promotes Their Differentiation into Functionally and Phenotypically Immature Macrophages

Directory of Open Access Journals (Sweden)

Leslie Chávez-Galán

2015-01-01

Full Text Available Lipoarabinomannan (LAM is a lipid virulence factor secreted by Mycobacterium tuberculosis (Mtb, the etiologic agent of tuberculosis. LAM can be measured in the urine or serum of tuberculosis patients (TB-patients. Circulating monocytes are the precursor cells of alveolar macrophages and might be exposed to LAM in patients with active TB. We speculated that exposing monocytes to LAM could produce phenotypically and functionally immature macrophages. To test our hypothesis, human monocytes were stimulated with LAM (24–120 hours and various readouts were measured. The study showed that when monocytes were exposed to LAM, the frequency of CD68+, CD33+, and CD86+ macrophages decreased, suggesting that monocyte differentiation into mature macrophages was affected. Regarding functionality markers, TLR2+ and TLR4+ macrophages also decreased, but the percentage of MMR+ expression did not change. LAM-exposed monocytes generated macrophages that were less efficient in producing proinflammatory cytokines such as TNF-α and IFN-γ; however, their phagocytic capacity was not modified. Taken together, these data indicate that LAM exposure influenced monocyte differentiation and produced poorly functional macrophages with a different phenotype. These results may help us understand how mycobacteria can limit the quality of the innate and adaptive immune responses.

Electron beam processing of fresh produce - A critical review

Science.gov (United States)

Pillai, Suresh D.; Shayanfar, Shima

2018-02-01

To meet the increasing global demand for fresh produce, robust processing methods that ensures both the safety and quality of fresh produce are needed. Since fresh produce cannot withstand thermal processing conditions, most of common safety interventions used in other foods are ineffective. Electron beam (eBeam) is a non-thermal technology that can be used to extend the shelf life and ensure the microbiological safety of fresh produce. There have been studies documenting the application of eBeam to ensure both safety and quality in fresh produce, however, there are still unexplored areas that still need further research. This is a critical review on the current literature on the application of eBeam technology for fresh produce.

Clinical manifestations, diagnosis, and treatment of Mycobacterium haemophilum infections.

NARCIS (Netherlands)

Lindeboom, J.A.; Bruijnesteijn van Coppenraet, L.E.; Soolingen, D. van; Prins, J.M.; Kuijper, E.J.

2011-01-01

Mycobacterium haemophilum is a slowly growing acid-fast bacillus (AFB) belonging to the group of nontuberculous mycobacteria (NTM) frequently found in environmental habitats, which can colonize and occasionally infect humans and animals. Several findings suggest that water reservoirs are a likely

Clinical manifestations, diagnosis, and treatment of Mycobacterium haemophilum infections

NARCIS (Netherlands)

Lindeboom, J.A.; Bruijnesteijn van Coppenraet, L.E.S.; van Soolingen, D.; Prins, J.M.; Kuijper, E.J.

2011-01-01

Mycobacterium haemophilum is a slowly growing acid-fast bacillus (AFB) belonging to the group of nontuberculous mycobacteria (NTM) frequently found in environmental habitats, which can colonize and occasionally infect humans and animals. Several findings suggest that water reservoirs are a likely

Thoracic imaging in AIDS

Energy Technology Data Exchange (ETDEWEB)

Barneveld Binkhuysen, F H [Eemland Hospital, Dept. of Radiology, Amersfoort (Netherlands)

1996-12-31

The contents are infectious diseases i.e. pneumocystis carinii, mycobacterium tuberculosis, atypical mycobacteria, fungal infections, viral infections ; Malignant diseases : kaposi`s sarcoma (KS), malignant lymphoma and other disorders i.e. lymphocytic interstitial pneumonitis, hypersensitivity reactions, bullous changes, pericardial abnormalities (15 refs.).

Yield of diagnostic tests for opportunistic infections in AIDS: a survey of 33 patients

DEFF Research Database (Denmark)

Gøtzsche, P C; Bygbjerg, Ib Christian; Olesen, B

1988-01-01

/7 disseminated infections with atypical mycobacteria were only revealed at autopsy, despite numerous cultures in vivo. Liver biopsies were not helpful. Diagnostic procedures for Pneumocystis carinii pneumonia by lung biopsy caused pneumothorax in 3/15 patients; bronchoalveolar lavage or treatment...

Characterization of a Mycobacterium leprae antigen related to the secreted Mycobacterium tuberculosis protein MPT32

NARCIS (Netherlands)

Wieles, B.; van Agterveld, M.; Janson, A.; Clark-Curtiss, J.; Rinke de Wit, T.; Harboe, M.; Thole, J.

1994-01-01

Secreted proteins may serve as major targets in the immune response to mycobacteria. To identify potentially secreted Mycobacterium leprae antigens, antisera specific for culture filtrate proteins of Mycobacterium tuberculosis were used to screen a panel of recombinant antigens selected previously

Thoracic imaging in AIDS

International Nuclear Information System (INIS)

Barneveld Binkhuysen, F.H.

1995-01-01

The contents are infectious diseases i.e. pneumocystis carinii, mycobacterium tuberculosis, atypical mycobacteria, fungal infections, viral infections ; Malignant diseases : kaposi's sarcoma (KS), malignant lymphoma and other disorders i.e. lymphocytic interstitial pneumonitis, hypersensitivity reactions, bullous changes, pericardial abnormalities (15 refs.)

Otomastoiditis Caused by Mycobacterium abscessus, the Netherlands

NARCIS (Netherlands)

van Ingen, Jakko; Looijmans, Frank; Mirck, Piet; Dekhuijzen, Richard; Boeree, Martin; van Soolingen, Dick

2010-01-01

To the Editor: Nontuberculous mycobacteria (NTM) are increasingly recognized as human pathogens (1). Otomastoiditis is a rare extrapulmonary NTM disease type first described in 1976; Mycobacterium chelonae-M. abscessus group bacteria, which are rapidly growing NTM, are the most frequent causative

THE PERSISTENCE OF MYCOBACTERIUM AVIUM IN A DRINKING WATER SYSTEM AFTER THE ADDITION OF FILTRATION

Science.gov (United States)

Drinking water is increasingly recognized as a major source of pathogenic nontuberculous mycobacteria (NTM) associated with human infection. Our goal was to determine if the prevalence of NTM would decrease after the addition of filtration treatment to an unfiltered surface water...

Genetic diversity of Mycobacterium tuberculosis in Mbarara, South ...

African Journals Online (AJOL)

Background: We determined the genetic diversity of mycobacteria isolated from tuberculosis patients in Mbarara Uganda, using region of difference (RD) analysis and spacer oligonucleotide typing (spoligotyping). Methods: Sputum samples were cultured on Lowenstein Jensen media. The isolates were characterized using ...

A survey of the bacterial diversity in the cup filler of dental chair units.

Science.gov (United States)

Silva, Vítor; Figueira, Vânia; Figueiral, Helena; Manaia, Célia M

2011-07-01

Water from the cup filler of dental chair units (CFDC) was observed to contain sphingomonads, environmental mycobacteria and methylobacteria, among other minor bacteria. Some of the bacteria detected are recognized opportunistic pathogens. Some of these, tended to persist over time.

Epidemiology and management of mycobacterial infections in the immunocompromised patient

Directory of Open Access Journals (Sweden)

Maximo O Brito

2015-01-01

The author will review the epidemiology, clinical presentation, diagnostic methods and principles of treatment of the most common mycobacteria that cause disease in HIV and transplant recipients, and will discuss some of the nuances in the management of these patients.

LTBI: latent tuberculosis infection or lasting immune responses to M. tuberculosis? A TBNET consensus statement

DEFF Research Database (Denmark)

Mack, U; Migliori, G B; Sester, M

2009-01-01

. tuberculosis after tuberculin skin test or IGRA conversion is unknown. It is also uncertain how long adaptive immune responses towards mycobacterial antigens persist in the absence of live mycobacteria. Clinical management and public healthcare policies for preventive chemotherapy against tuberculosis could...

Understanding producers' motives for adopting sustainable practices

NARCIS (Netherlands)

Trujillo-Barrera, Andres; Pennings, Joost M.E.; Hofenk, Dianne

2016-01-01

Understanding the motives and risk attitudes of producers to engage in sustainable practices is important for policy-makers who wish to increase the likelihood of adoption and improve the design of incentives. This article examines the underlying motives of producers to adopt sustainable

Producer services, economic geography, and services tradability

NARCIS (Netherlands)

de Vaal, A; van den Berg, M

We investigate how the incorporation of producer services linkages affects the outcome of an economic geography model. We specify the production of manufactures such that a variety of producer services is needed to transform tradable unfinished goods into final consumption goods. We find that

Review of extended producer responsibility: A case study approach.

Science.gov (United States)

Gupt, Yamini; Sahay, Samraj

2015-07-01

Principles of extended producer responsibility have been the core of most of the recent policies and legislation dealing with the end-of-life management of recyclable goods. This article makes an exploratory review of 27 cases of extended producer responsibility from developed and developing economies with and without informal recycling, to ascertain the most important aspect of extended producer responsibility. A comparative analysis of the cases with respect to role of stakeholders in the upstream and downstream stages of the extended producer responsibility has been carried out. Further, the study uses exploratory factor analysis to determine the important aspects of the extended producer responsibility in practice using 13 variables identified from the review. Findings of the comparative analysis reveal that financial responsibility of the producers and separate collecting and recycling agencies contributed significantly to the success of the extended producer responsibility-based environmental policies. Regulatory provisions, take-back responsibility and financial flow come out to be the three most important aspects of the extended producer responsibility. Presence of informal sector had a negative impact on the regulatory provisions. The outcomes of this study could serve as a guideline for designing of effective extended producer responsibility-based policies. © The Author(s) 2015.

ANAEROBIC BIOLOGICAL TREATMENT OF PRODUCED WATER; TOPICAL

International Nuclear Information System (INIS)

John R. Gallagher

2001-01-01

During the production of oil and gas, large amounts of water are brought to the surface and must be disposed of in an environmentally sensitive manner. This is an especially difficult problem in offshore production facilities where space is a major constraint. The chief regulatory criterion for produced water is oil and grease. Most facilities have little trouble meeting this criterion using conventional oil-water separation technologies. However, some operations have significant amounts of naphthenic acids in the water that behave as oil and grease but are not well removed by conventional technologies. Aerobic biological treatment of naphthenic acids in simulated-produced water has been demonstrated by others; however, the system was easily overloaded by the large amounts of low-molecular-weight organic acids often found in produced waters. The objective of this research was to determine the ability of an anaerobic biological system to treat these organic acids in a simulated produced water and to examine the potential for biodegradation of the naphthenic acids in the anaerobic environment. A small fixed-film anaerobic biological reactor was constructed and adapted to treat a simulated produced water. The bioreactor was tubular, with a low-density porous glass packing material. The inocula to the reactor was sediment from a produced-water holding pond from a municipal anaerobic digester and two salt-loving methanogenic bacteria. During start-up, the feed to the reactor contained glucose as well as typical produced-water components. When glucose was used, rapid gas production was observed. However, when glucose was eliminated and the major organic component was acetate, little gas was generated. Methane production from acetate may have been inhibited by the high salt concentrations, by sulfide, or because of the lack, despite seeding, of microbes capable of converting acetate to methane. Toluene, a minor component of the produced water (0.1 g/L) was removed in the

Biosurfactant-producing yeasts widely inhabit various vegetables and fruits.

Science.gov (United States)

Konishi, Masaaki; Maruoka, Naruyuki; Furuta, Yoshifumi; Morita, Tomotake; Fukuoka, Tokuma; Imura, Tomohiro; Kitamoto, Dai

2014-01-01

The isolation of biosurfactant-producing yeasts from food materials was accomplished. By a combination of a new drop collapse method and thin-layer chromatography, 48 strains were selected as glycolipid biosurfactant producers from 347 strains, which were randomly isolated from various vegetables and fruits. Of the producers, 69% were obtained from vegetables of the Brassica family. Of the 48 producers, 15 strains gave relatively high yields of mannosylerythritol lipids (MELs), and were identified as Pseudozyma yeasts. These strains produced MELs from olive oil at yields ranging from 8.5 to 24.3 g/L. The best yield coefficient reached 0.49 g/g as to the carbon sources added. Accordingly, MEL producers were isolated at high efficiency from various vegetables and fruits, indicating that biosurfactant producers are widely present in foods. The present results should facilitate their application in the food and related industries.

Method for producing carbon nanotubes

Science.gov (United States)

Phillips, Jonathan [Santa Fe, NM; Perry, William L [Jemez Springs, NM; Chen, Chun-Ku [Albuquerque, NM

2006-02-14

Method for producing carbon nanotubes. Carbon nanotubes were prepared using a low power, atmospheric pressure, microwave-generated plasma torch system. After generating carbon monoxide microwave plasma, a flow of carbon monoxide was directed first through a bed of metal particles/glass beads and then along the outer surface of a ceramic tube located in the plasma. As a flow of argon was introduced into the plasma through the ceramic tube, ropes of entangled carbon nanotubes, attached to the surface of the tube, were produced. Of these, longer ropes formed on the surface portion of the tube located in the center of the plasma. Transmission electron micrographs of individual nanotubes revealed that many were single-walled.

Quantification of microcystin-producing microcystis in freshwater ...

African Journals Online (AJOL)

Total Microcystis spp (microcystinproducing and non-producing strains) were quantified in the three selected study areas with the determination of the copy numbers of the phycocyanin (PC) operon. Microcystin-producing gene copy numbers were quantified using specific primer pair, amplifying the mcyB gene. Microcystis ...

Screening of thermophilic neutral lipase-producing Pseudomonas ...

African Journals Online (AJOL)

From oil-contaminated soil, three lipase-producing microorganisms were selected as good lipase producers using rhodamine B-olive oil plate agar and they were identified as from Pseudomonas, Burkholderia and Klebsiella genera by morphology, biochemical characterization and 16S rRNA gene sequencing. Among the ...

Sideways wall force produced during tokamak disruptions

Science.gov (United States)

Strauss, H.; Paccagnella, R.; Breslau, J.; Sugiyama, L.; Jardin, S.

2013-07-01

A critical issue for ITER is to evaluate the forces produced on the surrounding conducting structures during plasma disruptions. We calculate the non-axisymmetric ‘sideways’ wall force Fx, produced in disruptions. Simulations were carried out of disruptions produced by destabilization of n = 1 modes by a vertical displacement event (VDE). The force depends strongly on γτwall, where γ is the mode growth rate and τwall is the wall penetration time, and is largest for γτwall = constant, which depends on initial conditions. Simulations of disruptions caused by a model of massive gas injection were also performed. It was found that the wall force increases approximately offset linearly with the displacement from the magnetic axis produced by a VDE. These results are also obtained with an analytical model. Disruptions are accompanied by toroidal variation of the plasma current Iφ. This is caused by toroidal variation of the halo current, as verified computationally and analytically.

Strategies of development of European power producers

International Nuclear Information System (INIS)

Heddebaut, D.

2007-12-01

This economical study answers the following questions: what is the dynamics of European power markets? What is the relative competitiveness of the different power production means? What are the determining factors of electricity wholesale prices? Who are the operators the most threatened by the rise of wholesale prices? To what extend power producers are impacted by the CO 2 constrain? Who are the most efficient producers? The analysis is based on 18 of the most representative groups of the European electric utilities. The first volume of the study presents the strategic perspectives of European power producers: dynamics and basic characteristics of European power markets, strategic options of European operators, typology and financial results of European power producers, scenarios of market reorganization according to Eurostaf (possible mega-mergers in the future, competition). Volume 2 makes a detailed analysis of the positioning and perspectives of the 18 selected groups: key figures, sourcing strategies, production means management, Eurostaf's diagnosis. (J.S.)

Distribution alternatives for a small wine-producer

Directory of Open Access Journals (Sweden)

Radka Šperková

2010-01-01

Full Text Available Distribution can be defined as a way of goods from producer to consumer. In wine production industry there exist several distribution channels, through which wine is distributed to the final consumer. Aim of this paper is to identify and compare advantages and disadvantages of particular distribution channels for wine sales related to a small wine-producer.Distribution of wine to the final consumer is done through dealers represented by retail chains, specialized wine-shops, hotels, and restaurants. In a smaller scale it is done through internet sales, own outlets and wine auctions. According to the research of Focus agency, Marketing & Social Research, done in 2009, customers buy wine mostly in retail chains and decide on sort and quality of wine directly at the moment of purchase. Selection is based except wine quality also on the shape of the bottle, etiquette, and also cork (consumers explicitly prefer cork, and the screw top rather discourages. Certain part of customers – specifically those, who are more acquainted with wine – buy wine in special wine-shops. The research shows a decrease of direct wine-sales.When using services of independent trade organizations, producers have to control the intensity of commercial activities and knowledge of technical characteristics of products. Small wine producers, though, do not have to use this distribution channel, and can focus only on direct sales. For some small wine producers, specifically those operating in the areas with an extended possibility for wine-tourism, this channel can be more suitable and effective than using retail chains. This way of distribution does not require extensive start-up investments, it is directly dependent on producers own effort, and can be done as a supplementary activity to the main source of income.Regardless the particular choice of a distribution channel by a small wine producer it is necessary to be judged not only from the viewpoint of its advantages and