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Sample records for rapidly growing mycobacteria

  1. Post liposuction infections by rapidly growing mycobacteria.

    PubMed

    Zosso, Caroline; Lienhard, Reto; Siegrist, Hans H; Malinverni, Raffaele; Clerc, Olivier

    2015-02-01

    Rapidly growing mycobacteria (RGM) are recognized agents of surgical site infections. Recently, RGM skin and soft tissue infections have been increasingly reported. As symptoms, clinical signs and disease latency remain non-specific and microbiological detection requires targeted growth media, RGM diagnosis remains challenging for clinicians. Appropriate management is often delayed due to lack of awareness of these infections. RGM infections after plastic surgery have also been described in the setting of interventions performed in developing countries, a growing phenomenon commonly known as medical tourism. We describe a case of Mycobacterium chelonae/abscessus infection following liposuction and liposculpture procedures performed in the Dominican Republic and review the literature on this subject.

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

    EPA Science Inventory

    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...

  3. Rapidly growing nontuberculous mycobacteria cultured from home tap and shower water.

    PubMed

    van Ingen, Jakko; Blaak, Hetty; de Beer, Jessica; de Roda Husman, Ana Maria; van Soolingen, Dick

    2010-09-01

    Tap and shower water at two locations in the Netherlands was examined for the presence of rapidly growing nontuberculous mycobacteria. Cultures yielded Mycobacterium peregrinum, M. salmoniphilum, M. llatzerense, M. septicum, and three potentially novel species, a distribution different from that in clinical samples. PMID:20639378

  4. Pulmonary infection with rapidly growing mycobacteria in a singer with achalasia: a case report.

    PubMed

    Cramer, J P; Sudeck, H; Burchard, G D

    2007-04-01

    We report the case of a 37-year-old male patient with prolonged pneumonia and achalasia. Culture and molecular genetic typing identified Mycobacterium abscessus as causative agent. Treatment with clarithromycin and minocycline over 8 months gradually resolved the infection. Rapidly growing, non-obligate pathogenic mycobacteria are widespread in the environment. Several cases of pulmonary infections with these mycobacteria in patients with achalasia have been reported, suggesting a causative association. This is the first report of a case with isolation of M. abscessus in this context. PMID:17316814

  5. Rapidly Growing Mycobacteria Associated with Laparoscopic Gastric Banding, Australia, 2005–2011

    PubMed Central

    Thomson, Rachel M.; Reid, Alistair B.; Carter, Robyn; Bartley, Paul B.; Newton, Peter; Coulter, Christopher

    2014-01-01

    Laparoscopic gastric banding is a common bariatric procedure worldwide. Rapidly growing mycobacteria are environmental organisms increasingly seen as pathogens, often in infected prosthetic material. We report 18 cases of infection associated with laparoscopic gastric banding caused by Mycobacterium fortuitum and M. abscessus in Australia during 2005–2011. We identified cases by reviewing positive cultures at the Queensland state reference laboratory or through correspondence with clinicians, and we obtained clinical and epidemiologic data. Eleven cases of M. fortuitum and 7 cases of M. abscessus infection were identified. The port was thought to be the primary site of infection in 10 of these cases. Complications included peritonitis, band erosion, and chronic ulceration at the port site. Rapidly growing mycobacteria can infect both port and band and can occur as either an early perioperative or late infection. Combination antimicrobial therapy is used on the basis of in vitro susceptibilities. Device removal seems to be vital to successful therapy. PMID:25279450

  6. Surgical Site Infections Due to Rapidly Growing Mycobacteria in Puducherry, India

    PubMed Central

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

    2015-01-01

    Background: 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. Materials and Methods: 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. Results: 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. Conclusion: 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. PMID:25954616

  7. Mercuric reductase activity and evidence of broad-spectrum mercury resistance among clinical isolates of rapidly growing mycobacteria

    SciTech Connect

    Steingrube, V.A.; Wallace, R.J. Jr.; Steele, L.C.; Pang, Y.J. )

    1991-05-01

    Resistance to mercury was evaluated in 356 rapidly growing mycobacteria belonging to eight taxonomic groups. Resistance to inorganic Hg2+ ranged from 0% among the unnamed third biovariant complex of Mycobacterium fortuitum to 83% among M. chelonae-like organisms. With cell extracts and 203Hg(NO3)2 as the substrate, mercuric reductase (HgRe) activity was demonstrable in six of eight taxonomic groups. HgRe activity was inducible and required NADPH or NADH and a thiol donor for optimai activity. Species with HgRe activity were also resistant to organomercurial compounds, including phenylmercuric acetate. Attempts at intraspecies and intragenus transfer of HgRe activity by conjugation or transformation were unsuccessful. Mercury resistance is common in rapidly growing mycobacteria and appears to function via the same inducible enzyme systems already defined in other bacterial species. This system offers potential as a strain marker for epidemiologic investigations and for studying genetic systems in rapidly growing mycobacteria.

  8. In vitro susceptibilities of rapidly growing mycobacteria to newer antimicrobial agents.

    PubMed Central

    Khardori, N; Nguyen, H; Rosenbaum, B; Rolston, K; Bodey, G P

    1994-01-01

    The in vitro antimicrobial susceptibilities of 42 isolates of rapidly growing mycobacteria (Mycobacterium fortuitum, M. chelonae, and Mycobacterium species [other than M. fortuitum and M. chelonae]) to nine quinolones, including newer agents, two new aminoglycosides, and an aminocyclitol (trospectomycin) were determined by a broth microdilution method. The new quinolones, PD 117596, PD 127391, and PD 117558, showed excellent in vitro activities against M. fortuitum (MICs for 90% of isolates [MIC90s], 0.06, 0.06, and 0.12 microgram/ml, respectively). The MIC90 of ciprofloxacin for M. fortuitum was 0.5 microgram/ml. Only 14 to 28% of isolates of M. chelonae were susceptible to various quinolones. Most isolates of all three species were susceptible to the new aminoglycosides SCH 21420 and SCH 22591. The MIC90s of trospectomycin were 8 micrograms/ml for M. chelonae, 32 micrograms/ml for Mycobacterium species, and > 64 micrograms/ml for M. fortuitum. PMID:8141567

  9. Complete Genome Sequence of Mycobacterium chelonae Type Strain CCUG 47445, a Rapidly Growing Species of Nontuberculous Mycobacteria

    PubMed Central

    Jaén-Luchoro, Daniel; Salvà-Serra, Francisco; Aliaga-Lozano, Francisco; Seguí, Carolina; Busquets, Antonio; Ramírez, Antonio; Ruíz, Mikel; Gomila, Margarita; Lalucat, Jorge

    2016-01-01

    Mycobacterium chelonae strains are ubiquitous rapidly growing mycobacteria associated with skin and soft tissue infections, cellulitis, abscesses, osteomyelitis, catheter infections, disseminated diseases, and postsurgical infections after implants with prostheses, transplants, and even hemodialysis procedures. Here, we report the complete genome sequence of M. chelonae type strain CCUG 47445. PMID:27284158

  10. [Evaluation of rapidly growing Mycobacteria isolates in a general hospital: reports from the hospital microbiology laboratory].

    PubMed

    Tazawa, S; Marumo, K; Nakamura, Y; Narushima, M; Higuchi, D

    2001-05-01

    Forty isolates of rapidly growing Mycobacteria, Mycobacterium fortuitum group including M. fortuitum and M. peregrinum and M. chelonae group including M. chelonae subsp. chelonae and M. chelonae subsp. abscessus at Showa University Fujigaoka Hospital collected between February 1981 and December 1997 were investigated in this study. These isolates were from the patients who were not infected with HIV. The average age of fourteen patients, from whom M. fortuitum group was isolated, was 58 years, ranging from 17 to 80 years old. One patient (71-year-old) with chronic myelogenous leukemia and another (64-year-old) with chronic diabetes mellitus were diagnosed with skin abscesses of M. fortuitum group, which were located on the right site of the neck and in the scar after injecting insulin (injection abscess), respectively. The average age of twenty-six patients, from whom M. chelonae group was isolated, was 57 years, ranging from 32 to 84 years old. One patient (75-year-old) with articular rheumatism was diagnosed with a lung infection of mixed M. chelonae group and Pseudomonas aeruginosa, and another (74-year-old) with diabetes mellitus and kidney failure was strongly suspected of a lung infection. The isolates of the two mycobacteria from the remaining patients were due to colonization, while these patients had the following underlying diseases contributing to infections: pulmonary emphysema; diabetes mellitus; leukemia; collagen diseases; lung cancer; chronic kidney diseases; systemic lupus erythematosus; carcinomatous pleurisy; bronchiectasis; post-tuberculosis. Most isolates of the two mycobacteria were separated from the specimens of patients' respiratory tracts, but since M. chelonae group was a contaminant in the tap-water for diluting concentrated chlorhexidine, the organism happened to be isolated with the mucous membranes of the 6 patients' colons that were picked up while using the washed fiber-scope. These findings suggest that M. fortuitum and M. chelonae

  11. Clinical features of pulmonary disease caused by rapidly growing mycobacteria. An analysis of 154 patients.

    PubMed

    Griffith, D E; Girard, W M; Wallace, R J

    1993-05-01

    The role of rapidly growing mycobacteria (RGM) as pulmonary pathogens has been unclear. We identified 154 cases of lung disease caused by RGM using the microbiologic and radiographic criteria of the American Thoracic Society (ATS) and availability of the causative organism for study. More than one third of patients had positive lung biopsy cultures. Patients were predominantly white (83%), female (65%) nonsmokers (66%), and they had prolonged periods from onset of symptoms to diagnosis of their disease. Cough was an almost universal presenting symptom, whereas constitutional symptoms became more important with progression of disease. Upper lobe infiltrates were most common (88%), with 77% of patients developing bilateral disease. Cavitation was present in only 16% of the patients. Specific underlying diseases were infrequent, but they included previously treated mycobacterial disease (18%), coexistent Mycobacterium avium complex (8%), cystic fibrosis (6%), and gastroesophageal disorders with chronic vomiting (6%). The majority of isolates (82%) were M. abscessus (formerly M. chelonae subsp. abscessus). Effective treatment for M. fortuitum long disease was accomplished with drug therapy, whereas surgical resection of localized disease was the only effective long-term therapy for M. abscessus. Although the disease was generally slowly progressive, 21 of 154 (14%) patients died as a consequence of progressive RGM lung disease and respiratory failure. RGM should be recognized as a cause of chronic mycobacterial lung disease, and respiratory isolates should be assessed carefully. PMID:8484642

  12. In vitro drug susceptibility of 40 international reference rapidly growing mycobacteria to 20 antimicrobial agents

    PubMed Central

    Pang, Hui; Li, Guilian; Wan, Li; Jiang, Yi; Liu, Haican; Zhao, Xiuqin; Zhao, Zhongfu; Wan, Kanglin

    2015-01-01

    Rapidly growing mycobacteria (RGM) are human pathogens that are relatively easily identified by acid-fast staining but are proving difficult to treat in the clinic. In this study, we performed susceptibility testing of 40 international reference RGM species against 20 antimicrobial agents using the cation-adjusted Mueller-Hinton (CAMH) broth microdilution based on the minimum inhibitory concentration (MIC) assay recommended by the guidelines of the Clinical and Laboratory Standards Institute (CLSI). The results demonstrated that RGM organisms were resistant to the majority of first-line antituberculous agents but not to second-line fluoroquinolones or aminoglycosides. Three drugs (amikacin, tigecycline and linezolid) displayed potent antimycobacterial activity against all tested strains. Capreomycin, levofloxacin and moxifloxacin emerged as promising candidates for the treatment of RGM infections, and cefoxitin and meropenem were active against most strains. Mycobacterium chelonae (M. chelonae), M. abscessus, M. bolletii, M. fortuitum, M. boenickei, M. conceptionense, M. pseudoshottsii, M. septicum and M. setense were the most resistant RGM species. These results provide significant insight into the treatment of RGM species and will assist optimization of clinical criteria. PMID:26629031

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

    PubMed Central

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

    2015-01-01

    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. PMID:26351633

  14. [Infections by rapidly growing mycobacteria resistant to disinfectants: a national matter?].

    PubMed

    Pitombo, Marcos Bettini; Lupi, Otília; Duarte, Rafael Silva

    2009-11-01

    Rapidly growing mycobacteria (RGM) are opportunistic microorganisms and widely distributed into aqueous environment and soil. Human RGM infections are usually associated with contaminated solutions or medical instruments used during invasive procedures. RGM postsurgical infections have recently emerged in Brazil and have caused national alert, considering the risk factors and epidemiological aspects. This study aimed at analysing the main factors linked to the recent RGM outbreaks, with focus on the national epidemic of Mycobacterium massiliense infections related to the BRA100 strains resistant to 2% glutaraldehyde commercial solutions commonly used for preoperative high-level disinfection. Based on previous studies and laboratorial results of assays and colaborations, it has been observed that the cases have been associated with videolaparoscopy for different applications and elective esthetic procedures, such as lipoaspiration and mammary prosthesis implant. Furthermore, outbreaks between 2004 and 2008 and the epidemic in Rio de Janeiro state may be considered particular Brazilian events. Although there are a few epidemiological published studies, some hypotheses based on common aspects related to most national nosocomial occurrences are possible, such as lack of protocols for cleaning and high-level disinfection, use of 2% glutaraldehyde as high-level disinfectant for surgical instruments, and dissemination of M. massiliense BRA100 by unknown mechanisms.

  15. Polyclonality among clinical strains of non-pigmented rapidly growing mycobacteria: phenotypic and genotypic differences and their potential implications.

    PubMed

    García-Pedrazuela, M; Frutos, J M; Muñoz-Egea, M C; Alcaide, F; Tórtola, T; Vitoria, A; Cortés, P; Esteban, J

    2015-04-01

    To investigate the potential implications (especially the implications in clinical significance and antimicrobial susceptibility) of polyclonality among rapidly growing mycobacteria, we performed random amplified polymorphic DNA analysis in 64 clinical isolates of which the clinical significance was established. Phenotypic characteristics (antimicrobial susceptibility test, colony morphology and growth rate) of each clone were studied. Polyclonality was detected in 13 of the isolates (20.3%). There was a relationship between monoclonality and clinical significance (p 0.0096). Monoclonal and polyclonal isolates showed different behaviour in antimicrobial susceptibility. There was a strong relationship between monoclonality and those species that are more pathogenic for humans, and also with clinical significance of the isolates. PMID:25596780

  16. Analysis of a panel of rapidly growing mycobacteria for resistance to aldehyde-based disinfectants.

    PubMed

    De Groote, Mary Ann; Gibbs, Sara; de Moura, Vinicius Calado Nogueira; Burgess, Winona; Richardson, Kris; Kasperbauer, Shannon; Madinger, Nancy; Jackson, Mary

    2014-08-01

    After several accounts across the globe of mycobacteria outbreaks associated with medical procedures and aldehyde disinfectants resistance, we undertook an analysis of mycobacteria isolated from patients seen in a hospital in the United States between 1994 and 2008 to determine prevalence of resistance to aldehyde-based disinfectants. Out of the 117 clinical isolates screened, 6 isolates belonging to the emerging Mycobacterium abscessus group were found to display significant levels of resistance to glutaraldehyde and ortho-phthalaldehyde.

  17. Draft Genome Sequence of Mycobacterium wolinskyi, a Rapid-Growing Species of Nontuberculous Mycobacteria.

    PubMed

    de Man, Tom J B; Perry, K Allison; Lawsin, Adrian; Coulliette, Angela D; Jensen, Bette; Toney, Nadege C; Limbago, Brandi M; Noble-Wang, Judith

    2016-01-01

    Mycobacterium wolinskyi is a nonpigmented, rapidly growing nontuberculous mycobacterium species that is associated with bacteremia, peritonitis, infections associated with implants/prostheses, and skin and soft tissue infections often following surgical procedures in humans. Here, we report the first functionally annotated draft genome sequence of M. wolinskyi CDC_01. PMID:26988052

  18. Mycobacterial contamination of metalworking fluids: involvement of a possible new taxon of rapidly growing mycobacteria.

    PubMed

    Moore, J S; Christensen, M; Wilson, R W; Wallace, R J; Zhang, Y; Nash, D R; Shelton, B

    2000-01-01

    Contamination of air and metalworking fluid (MWF) systems with a rapidly growing mycobacterium (RGM) was detected in 1995 in a single manufacturing plant with recent cases of hypersensitivity pneumonitis (HP). Extensive environmental sampling was performed to determine the extent of the contamination and its variability over time. RGM were present in multiple indoor air samples, 100% of the central MWF storage tanks, and 75% of the freestanding cutting, drilling, and grinding machines. With one exception, contamination was limited to a recently introduced formulation (brand) of semisynthetic MWF used in 95% of the facility's machining operations. In general, the mycobacterial counts were stable over time, with the degree of contamination ranging from 10(2)-10(7) colony forming units (CFU)/mL. A few systems were culture positive for the mycobacterium (> 10(1) CFU/mL), changed to culture negative (< 10(1) CFU/mL), then changed back to culture positive without explanation. Samples obtained from diluted (5%) but unused MWF, a replenishment line with 2% unused MWF, an MWF pasteurizer, city water, and deionized water were culture negative for this species of mycobacterium. Inoculation and growth studies demonstrated that this mycobacterium does not grow in liquid samples of 5% unused MWF. By molecular techniques, the mycobacterial isolates consisted of a single strain and represented a previously undescribed taxon closely related to Mycobacterium chelonae/abscessus. The relationship of this mycobacterium to the cases of HP is unknown.

  19. Effect of Antibiotics and Antibiofilm Agents in the Ultrastructure and Development of Biofilms Developed by Nonpigmented Rapidly Growing Mycobacteria.

    PubMed

    Muñoz-Egea, María-Carmen; García-Pedrazuela, María; Mahillo-Fernandez, Ignacio; Esteban, Jaime

    2016-01-01

    We analyze the effect of amikacin, ciprofloxacin, and clarithromycin, alone and associated with N-acetylcysteine (NAC) and Tween 80, at different times and concentrations in nonpigmented rapidly growing mycobacteria (NPRGM) biofilms. For this purpose, confocal laser scanning microscopy and image analysis were used to study the development and behavior of intrinsic autofluorescence, covered area, thickness, and cell viability in NPRGM biofilms after adding antibiotics alone and associated with antibiofilm agents. In this study, ciprofloxacin is the most active antibiotic against this type of biofilm and thickness is the most affected parameter. NAC and Tween 80 combined with antibiotics exert a synergistic effect in increasing the percentage of dead bacteria and also reducing the percentage of covered surface and thickness of NPRGM biofilms. Tween 80 seems to be an antibiofilm agent more effective than NAC due to its higher reduction in the percentage of cover surface and thickness. In conclusion, the results obtained in this work show that phenotypic parameters (thickness, percentage of covered surface, autofluorescence, percentage of live/dead bacteria) are affected by combining antibiotics and antibiofilm agents, ciprofloxacin and Tween 80 being the most active agents against NPRGM biofilms.

  20. Effect of Antibiotics and Antibiofilm Agents in the Ultrastructure and Development of Biofilms Developed by Nonpigmented Rapidly Growing Mycobacteria.

    PubMed

    Muñoz-Egea, María-Carmen; García-Pedrazuela, María; Mahillo-Fernandez, Ignacio; Esteban, Jaime

    2016-01-01

    We analyze the effect of amikacin, ciprofloxacin, and clarithromycin, alone and associated with N-acetylcysteine (NAC) and Tween 80, at different times and concentrations in nonpigmented rapidly growing mycobacteria (NPRGM) biofilms. For this purpose, confocal laser scanning microscopy and image analysis were used to study the development and behavior of intrinsic autofluorescence, covered area, thickness, and cell viability in NPRGM biofilms after adding antibiotics alone and associated with antibiofilm agents. In this study, ciprofloxacin is the most active antibiotic against this type of biofilm and thickness is the most affected parameter. NAC and Tween 80 combined with antibiotics exert a synergistic effect in increasing the percentage of dead bacteria and also reducing the percentage of covered surface and thickness of NPRGM biofilms. Tween 80 seems to be an antibiofilm agent more effective than NAC due to its higher reduction in the percentage of cover surface and thickness. In conclusion, the results obtained in this work show that phenotypic parameters (thickness, percentage of covered surface, autofluorescence, percentage of live/dead bacteria) are affected by combining antibiotics and antibiofilm agents, ciprofloxacin and Tween 80 being the most active agents against NPRGM biofilms. PMID:26208145

  1. Clinical and laboratory aspects of the diagnosis and management of cutaneous and subcutaneous infections caused by rapidly growing mycobacteria.

    PubMed

    Kothavade, R J; Dhurat, R S; Mishra, S N; Kothavade, U R

    2013-02-01

    Rapidly growing mycobacteria (RGM) are known to cause pulmonary, extra-pulmonary, systemic/disseminated, and cutaneous and subcutaneous infections. The erroneous detection of RGM that is based solely on microscopy, solid and liquid cultures, Bactec systems, and species-specific polymerase chain reaction (PCR) may produce misleading results. Thus, inappropriate therapeutic measures may be used in dermatologic settings, leading to increased numbers of skin deformity cases or recurrent infections. Molecular tools such as the sequence analyses of 16S rRNA, rpoB and hsp65 or PCR restriction enzyme analyses, and the alternate gene sequencing of the superoxide dismutase (SOD) gene, dnaJ, the 16S-23S rRNA internal transcribed spacers (ITS), secA, recA1, dnaK, and the 32-kDa protein gene have shown promising results in the detection of RGM species. PCR restriction enzyme analyses (PRA) work better than conventional methods at identifying species that are closely related. Recently introduced molecular tools such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), pyrosequencing, DNA chip technology, and Beacon probes-combined PCR probes have shown comparable results in the detection of various species of RGM. Closely related RGM species (e.g., Mycobacterium fortuitum, M. chelonae, and M. abscessus) must be clearly differentiated using accurate molecular techniques because their therapeutic responses are species-specific. Hence, this paper reviews the following aspects of RGM: (i) its sources, predisposing factors, clinical manifestations, and concomitant fungal infections; (ii) the risks of misdiagnoses in the management of RGM infections in dermatological settings; (iii) the diagnoses and outcomes of treatment responses in common and uncommon infections in immunocompromised and immunocompetent patients; (iv) conventional versus current molecular methods for the detection of RGM; (v) the basic principles of a promising MALDI-TOF MS

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

    PubMed

    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. PMID:27053677

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

    PubMed Central

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

    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 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. PMID:23835173

  4. A cluster of central line-associated bloodstream infections due to rapidly growing nontuberculous mycobacteria in patients with hematologic disorders at a Japanese tertiary care center: an outbreak investigation and review of the literature.

    PubMed

    Tagashira, Yasuaki; Kozai, Yasuji; Yamasa, Hitomi; Sakurada, Masako; Kashiyama, Tetsuya; Honda, Hitoshi

    2015-01-01

    BACKGROUND Rapidly growing nontuberculous mycobacteria (RGM) are considered rare pathogens, causing central line-associated bloodstream infection. We identified an outbreak of central line-associated bloodstream infection due to RGM at a hematology-oncology ward during a 5-month period. DESIGN Outbreak investigation and literature review. SETTING A Japanese tertiary care center. PATIENTS Adults who were hospitalized at the hematology-oncology ward from October 15, 2011, through February 17, 2012. RESULTS A total of 5 patients with a bloodstream infection due to RGM (4 cases of Mycobacterium mucogenicum and 1 case of Mycobacterium canariasense infection) were identified; of these, 3 patients had acute myeloid leukemia, 1 had acute lymphocytic leukemia, and 1 had aplastic anemia. Four of the 5 patients received cord blood transplantation prior to developing the bloodstream infection. All central venous catheters in patients with a bloodstream infection were removed. These patients promptly defervesced after catheter removal and their care was successfully managed without antimicrobial therapy. Surveillance cultures from the environment and water detected M. mucogenicum and M. canariasense in the water supply of the hematology-oncology ward. The isolates from the bloodstream infection and water sources were identical on the basis of 16S-rRNA gene sequencing. CONCLUSIONS The source of RGM in the outbreak of bloodstream infections likely was the ward tap water supply. Awareness of catheter-related bloodstream infections due to nontuberculous mycobacteria should be emphasized, especially where immunocompromised patients are at risk. Also, using antimicrobials after catheter removal to treat central line-associated bloodstream infection due to RGM may not be necessary. Infect Control Hosp Epidemiol 2015;36(1): 76-80. PMID:25627764

  5. Activities of the glycylcyclines N,N-dimethylglycylamido-minocycline and N,N-dimethylglycylamido-6-demethyl-6-deoxytetracycline against Nocardia spp. and tetracycline-resistant isolates of rapidly growing mycobacteria.

    PubMed Central

    Brown, B A; Wallace, R J; Onyi, G

    1996-01-01

    Susceptibilities to the new semisynthetic tetracycline (Tet) compounds N,N-dimethylglycylamido-minocycline (DMG-MINO) and N,N-dimethylglycylamido-6-demethyl-6-deoxytetracycline (DMG-DMDOT) were compared with those to doxycycline, minocycline, and Tet for 198 Tet-resistant (Tetr) and 33 Tet-susceptible (Tets) clinical isolates of rapidly growing mycobacteria (RGM) including the Mycobacterium fortuitum group, Mycobacterium abscessus, Mycobacterium chelonae, and Mycobacterium mucogenicum and 68 isolates belonging to six taxa of Nocardia spp. All Tetr RGM were highly susceptible to the glycylcyclines. The MICs at which 50 and 90% of isolates are inhibited were < or = 0.125 and < or = 0.25 microgram/ml, respectively, for DMG-DMDOT and < or = 0.25 and 1 microgram/ml, respectively, for DMG-MINO. The MIC of DMG-DMDOT at which 50% of Tetr strains are inhibited was the same as that for Tets strains for each of the four taxa of RGM. The new agents were less active against Nocardia spp. MICs of DMG-DMDOT were comparable to those of minocycline except for the MICs for Nocardia brasiliensis sensu stricto, the new taxon Nocardia pseudobrasiliensis, and some isolates of Nocardia nova, against which they were four- to eightfold more active. The MICs of DMG-DMDOT were consistently lower than those of DMG-MINO for RGM. This class of drugs offers exciting therapeutic potential for RGM and for selected species of Nocardia. PMID:8849243

  6. Sequestration from Immune CD4^+ T Cells of Mycobacteria Growing in Human Macrophages

    NASA Astrophysics Data System (ADS)

    Pancholi, Preeti; Mirza, Asra; Bhardwaj, Nina; Steinman, Ralph M.

    1993-05-01

    CD4^+ helper T cells mediate resistance to tuberculosis, presumably by enhancing the antimicrobial activity of macrophages within which the Mycobacterium tuberculosis organism grows. A first step in resistance should be the presentation of mycobacterial antigens by macrophages to CD4^+ T cells. However, when the antigenic stimulus is limited to organisms growing in human monocytes, the organisms become sequestered from immune CD4^+ T cells. This block in presentation is selective for growing mycobacteria and not for other stimuli. Sequestration would allow replicating organisms to persist in infected individuals and may contribute to virulence.

  7. Rapid detection and determination of the aerodynamic size range of airborne mycobacteria associated with whirlpools.

    PubMed

    Schafer, Millie P; Martinez, Kenneth F; Mathews, Elaine S

    2003-01-01

    Novel environmental air and water mycobacteria sampling and analytical methods are needed to circumvent difficulties associated with the use of culture-based methodologies. To implement this objective, a commercial, clinical, genus DNA amplification method utilizing the polymerase chain reaction (PCR) was interfaced with novel air sampling strategies in the laboratory. Two types of air samplers, a three-piece plastic, disposable filter cassette and an eight-stage micro-orifice uniform deposit impactor (MOUDI), were used in these studies. In both samplers, 37-mm polytetrafluoroethylene (PTFE) filters were used. Use of the MOUDI sampler permitted the capture of airborne mycobacteria in discrete size ranges, an important parameter for relating the airborne mycobacteria cells to potential respirable particles (aerodynamic diameter <10 microm) capable of causing health effects. Analysis of the samples was rapid, requiring only 1-1.5 days, as no microbial culturing or DNA purification was required. This approach was then used to detect suspected mycobacteria contamination associated with pools at a large public facility. PCR was also used to analyze various water samples from these pools. Again, no culturing or sample purification was required. Water samples taken from all ultraviolet light/hydrogen peroxide-treated whirlpools tested positive for the presence of mycobacteria. No mycobacteria were detected in the chlorine-treated pools and the water main supply facility. All air samples collected in the proximity of the indoor whirlpools and the associated changing rooms were strongly positive for airborne mycobacteria. The airborne mycobacteria particles were predominantly collected on MOUDI stages 1-6 representing an aerodynamic size range of 0.5 to 9.9 microm. In conclusion, using this approach permits the rapid detection of mycobacteria contamination as well as the routine monitoring of suspected pools. The approach circumvents problems associated with culture

  8. A Novel Rapidly Growing Mycobacterium Species Causing an Abdominal Cerebrospinal Fluid Pseudocyst Infection

    PubMed Central

    Hussain, Cory K.; de Man, Tom J. B.; Toney, Nadege C.; Kamboj, Kamal; Balada-Llasat, Joan-Miquel; Wang, Shu-Hua

    2016-01-01

    Nontuberculous mycobacteria (NTM) are a rare cause of ventriculoperitoneal shunt infections. We describe the isolation and identification of a novel, rapidly growing, nonpigmented NTM from an abdominal cerebrospinal fluid pseudocyst. The patient presented with fevers, nausea, and abdominal pain and clinically improved after shunt removal. NTM identification was performed by amplicon and whole-genome sequencing.

  9. Two Rapidly Growing Mycobacterial Species Isolated from a Brain Abscess: First Whole-Genome Sequences of Mycobacterium immunogenum and Mycobacterium llatzerense

    PubMed Central

    Greninger, Alexander L.; Langelier, Charles; Cunningham, Gail; Keh, Chris; Melgar, Michael; Chiu, Charles Y.

    2015-01-01

    Rapidly growing mycobacteria are rarely found in central nervous system infections. We describe a case of polymicrobial infection in a brain abscess including two rapidly growing Mycobacterium species, M. immunogenum and M. llatzerense. The Mycobacterium isolates were distinguishable by molecular methods, and whole-genome sequencing showed <60% pairwise nucleotide identity. PMID:25926490

  10. Rapid identification of mycobacteria and rapid detection of drug resistance in Mycobacterium tuberculosis in cultured isolates and in respiratory specimens.

    PubMed

    Yam, Wing-Cheong; Siu, Kit-Hang Gilman

    2013-01-01

    Recent advances in molecular biology and better understanding of the genetic basis of drug resistance have allowed rapid identification of mycobacteria and rapid detection of drug resistance of Mycobacterium tuberculosis present in cultured isolates or in respiratory specimens. In this chapter, several simple nucleic acid amplification-based techniques are introduced as molecular approach for clinical diagnosis of tuberculosis. A one-tube nested IS6110-based polymerase chain reaction (PCR) is used for M. tuberculosis complex identification; the use of a multiplex allele-specific PCR is demonstrated to detect the isoniazid resistance; PCR-sequencing assays are applied for rifampicin and ofloxacin resistance detection and 16S rDNA sequencing is utilized for identification of mycobacterial species from cultures of acid fast bacilli (AFB). Despite the high specificity and sensitivity of the molecular techniques, mycobacterial culture remains the "Gold Standard" for tuberculosis diagnosis. Negative results of molecular tests never preclude the infection or the presence of drug resistance. These technological advancements are, therefore, not intended to replace the conventional tests, but rather have major complementary roles in tuberculosis diagnosis.

  11. Multistate US Outbreak of Rapidly Growing Mycobacterial Infections Associated with Medical Tourism to the Dominican Republic, 2013-2014(1).

    PubMed

    Schnabel, David; Esposito, Douglas H; Gaines, Joanna; Ridpath, Alison; Barry, M Anita; Feldman, Katherine A; Mullins, Jocelyn; Burns, Rachel; Ahmad, Nina; Nyangoma, Edith N; Nguyen, Duc B; Perz, Joseph F; Moulton-Meissner, Heather A; Jensen, Bette J; Lin, Ying; Posivak-Khouly, Leah; Jani, Nisha; Morgan, Oliver W; Brunette, Gary W; Pritchard, P Scott; Greenbaum, Adena H; Rhee, Susan M; Blythe, David; Sotir, Mark

    2016-08-01

    During 2013, the Maryland Department of Health and Mental Hygiene in Baltimore, MD, USA, received report of 2 Maryland residents whose surgical sites were infected with rapidly growing mycobacteria after cosmetic procedures at a clinic (clinic A) in the Dominican Republic. A multistate investigation was initiated; a probable case was defined as a surgical site infection unresponsive to therapy in a patient who had undergone cosmetic surgery in the Dominican Republic. We identified 21 case-patients in 6 states who had surgery in 1 of 5 Dominican Republic clinics; 13 (62%) had surgery at clinic A. Isolates from 12 (92%) of those patients were culture-positive for Mycobacterium abscessus complex. Of 9 clinic A case-patients with available data, all required therapeutic surgical intervention, 8 (92%) were hospitalized, and 7 (78%) required ≥3 months of antibacterial drug therapy. Healthcare providers should consider infection with rapidly growing mycobacteria in patients who have surgical site infections unresponsive to standard treatment.

  12. Mycobacteria Isolated from Angkor Monument Sandstones Grow Chemolithoautotrophically by Oxidizing Elemental Sulfur

    PubMed Central

    Kusumi, Asako; Li, Xian Shu; Katayama, Yoko

    2011-01-01

    To characterize sulfate-producing microorganisms from the deteriorated sandstones of Angkor monuments in Cambodia, strains of Mycobacterium spp. were isolated from most probable number-positive cultures. All five strains isolated were able to use both elemental sulfur (S0) for chemolithoautotrophic growth and organic substances for chemoorganoheterotrophic growth. Results of phylogenetic and phenotypic analyses indicated that all five isolates were rapid growers of the genus Mycobacterium and were most similar to Mycobacterium cosmeticum and Mycobacterium pallens. Chemolithoautotrophic growth was further examined in the representative strain THI503. When grown in mineral salts medium, strain THI503 oxidized S0 to thiosulfate and sulfate; oxidation was accompanied by a decrease in the pH of the medium from 4.7 to 3.6. The link between sulfur oxidation and energy metabolism was confirmed by an increase in ATP. Fluorescence microscopy of DAPI-stained cells revealed that strain THI503 adheres to and proliferates on the surface of sulfur particles. The flexible metabolic ability of facultative chemolithoautotrophs enables their survival in nutrient-limited sandstone environments. PMID:21747806

  13. Rapid identification of mycobacteria to the species level by polymerase chain reaction and restriction enzyme analysis--a case report of corneal ulcer.

    PubMed

    Chen, K H; Sheu, M M; Lin, S R

    1997-09-01

    We report a case of corneal ulcer caused by nontuberculous mycobacteria which was confirmed by smear and culture. We attempted a new method for the rapid identification of mycobacteria to the species level on the basis of evaluation by the polymerase chain reaction of the gene encoding. The method is involved with restriction enzyme analysis of PCR product obtained with primers common to all mycobacteria. Using the restriction enzyme Bst EII and Hae III, clinically relevant and other frequent laboratory isolates were differentiated to the species or subspecies level by PCR-restriction enzyme analysis. The main prevalence of pattern analysis is Mycobacterium chelonae subsp. abscessus in this case. The outcome suggests that PCR-restriction enzyme analysis should be a useful method for early diagnosis concerning nontuberculous mycobacterial keratitis. PMID:9348738

  14. Complete Genome Sequences of 17 Rapidly Growing Nontuberculous Mycobacterial Strains.

    PubMed

    Caverly, Lindsay J; Spilker, Theodore; LiPuma, John J

    2016-01-01

    We report the complete genome sequences of 17 rapidly growing nontuberculous mycobacterial (NTM) strains, including 16 Mycobacterium abscessus complex strains and one M. immunogenum strain. These sequences add value to studies of the genetic diversity of rapidly growing NTM strains recovered from human specimens. PMID:27660787

  15. Complete Genome Sequences of 17 Rapidly Growing Nontuberculous Mycobacterial Strains

    PubMed Central

    Spilker, Theodore; LiPuma, John J.

    2016-01-01

    We report the complete genome sequences of 17 rapidly growing nontuberculous mycobacterial (NTM) strains, including 16 Mycobacterium abscessus complex strains and one M. immunogenum strain. These sequences add value to studies of the genetic diversity of rapidly growing NTM strains recovered from human specimens. PMID:27660787

  16. [Rapid diagnosis of mycobacteria, especially Mycobacterium tuberculosis and Mycobacterium avium complex, using MB Check system].

    PubMed

    Saito, H; Tomioka, H; Sato, K; Inoue, K; Shigeto, E

    1992-07-01

    Fourty-five sputum specimens were subjected to isolation for mycobacteria either MB Check system (MB method; F. Hoffmann-La Roche Ltd., Basel, Switzerland) or 3% Ogawa egg medium (Ogawa method). Test sputum was treated with 4 volumes of 4% NaOH for 1-2 min and 0.1 ml of the resulting mixture was inoculated onto 3% Ogawa egg medium. The remaining portion of the mixture was neutralized with IN HCl, diluted with 1/15 M phosphate buffer (PB; pH 6.8), and subsequently centrifuged at 3,000 rpm for 20 min. The sediment was suspended in 1.5 ml of PB and 0.5 ml each was inoculated into MB Check M bottle (20 ml) supplemented with M supplement (1 ml). In MB method, bacterial growth was measured on Middlebrook 7H11 agar medium and Middlebrook 7H11 agar medium containing NAP (p-nitro-alpha-acetylamino-beta-hydroxy-propiophenone). Among 45 sputum specimens, the number of positive specimens for mycobacterial growth in the above two cultivation methods and time required for growth were as follows: 3% Ogawa egg medium; 12 specimens (26.7%) gave positive growth, including 7 of M. tuberculosis complex strains on 14-35 days (average 22 days) and 5 of M. avium complex strains on 14-21 days (average 18 days); MB method; 15 of specimens (33.3%) gave positive growth, including 8 of M. tuberculosis complex strains on 7-21 days (average 15 days), 6 of M. avium complex strains on 7-14 days (average 11 days) and 1 of M. scrofulaceum strain on 28 days. There was no specimen which was positive for mycobacterial growth on 3% Ogawa egg medium but negative on MB medium. PMID:1434318

  17. Role of real-time PCR (RT-PCR) in rapid diagnosis of tuberculous mycobacteria in different clinical samples.

    PubMed

    2014-02-01

    The study was aimed for molecular detection of mycobacterial DNA in different clinical samples using real-time polymerase chain reaction (RT-PCR) system and rapid diagnosis of tuberculosis. A total of 508 clinical specimens (blood 343, menstrual fluid 53, endometrial tissue 43, body fluid 36, pus from lymph nodes 18, sputum 8, urine 5 and semen 2) were included in this study. We extracted DNA using QIAamp DNA Mini Kit (QIAGEN, Germany) and performed real-time assay using Rotor-Gene Q machine from Corbett Research, Australia for specific amplification of IS6110 sequence of mycobacterial genome. The RT-PCR result was also compared with bacterial culture and acid-fast bacillus staining. RT-PCR assay showed positivity in 52 cases and negative in 456 cases. Corresponding positive results in culture and acid-fast bacillus staining methods were 49 cases and 24 cases respectively. The sensitivity and specificity of detecting Mycobacterium tuberculosis by RT-PCR were 93.87% and 98.69% respectively taking positive culture results as reference standards. The overall positive and negative predictive values were 88.46% and 99.34% respectively. RT-PCR is a useful diagnostic tool for rapid and sensitive detection of mycobacteria in different clinical samples. The easy processing, fast reporting and relative lack of contamination issues make it worthy as a possible replacement to time consuming culture techniques. Moreover, it has added advantage of quantification of mycobacterial DNA, hence bacterial load.

  18. Occurrence of Mycobacteria in Water Treatment Lines and in Water Distribution Systems

    PubMed Central

    Le Dantec, Corinne; Duguet, Jean-Pierre; Montiel, Antoine; Dumoutier, Nadine; Dubrou, Sylvie; Vincent, Véronique

    2002-01-01

    The frequency of recovery of atypical mycobacteria was estimated in two treatment plants providing drinking water to Paris, France, at some intermediate stages of treatment. The two plants use two different filtration processes, rapid and slow sand filtration. Our results suggest that slow sand filtration is more efficient for removing mycobacteria than rapid sand filtration. In addition, our results show that mycobacteria can colonize and grow on granular activated carbon and are able to enter distribution systems. We also investigated the frequency of recovery of mycobacteria in the water distribution system of Paris (outside buildings). The mycobacterial species isolated from the Paris drinking water distribution system are different from those isolated from the water leaving the treatment plants. Saprophytic mycobacteria (present in 41.3% of positive samples), potentially pathogenic mycobacteria (16.3%), and unidentifiable mycobacteria (54.8%) were isolated from 12 sites within the Paris water distribution system. Mycobacterium gordonae was preferentially recovered from treated surface water, whereas Mycobacterium nonchromogenicum was preferentially recovered from groundwater. No significant correlations were found among the presence of mycobacteria, the origin of water, and water temperature. PMID:12406720

  19. Multistate US Outbreak of Rapidly Growing Mycobacterial Infections Associated with Medical Tourism to the Dominican Republic, 2013-2014(1).

    PubMed

    Schnabel, David; Esposito, Douglas H; Gaines, Joanna; Ridpath, Alison; Barry, M Anita; Feldman, Katherine A; Mullins, Jocelyn; Burns, Rachel; Ahmad, Nina; Nyangoma, Edith N; Nguyen, Duc B; Perz, Joseph F; Moulton-Meissner, Heather A; Jensen, Bette J; Lin, Ying; Posivak-Khouly, Leah; Jani, Nisha; Morgan, Oliver W; Brunette, Gary W; Pritchard, P Scott; Greenbaum, Adena H; Rhee, Susan M; Blythe, David; Sotir, Mark

    2016-08-01

    During 2013, the Maryland Department of Health and Mental Hygiene in Baltimore, MD, USA, received report of 2 Maryland residents whose surgical sites were infected with rapidly growing mycobacteria after cosmetic procedures at a clinic (clinic A) in the Dominican Republic. A multistate investigation was initiated; a probable case was defined as a surgical site infection unresponsive to therapy in a patient who had undergone cosmetic surgery in the Dominican Republic. We identified 21 case-patients in 6 states who had surgery in 1 of 5 Dominican Republic clinics; 13 (62%) had surgery at clinic A. Isolates from 12 (92%) of those patients were culture-positive for Mycobacterium abscessus complex. Of 9 clinic A case-patients with available data, all required therapeutic surgical intervention, 8 (92%) were hospitalized, and 7 (78%) required ≥3 months of antibacterial drug therapy. Healthcare providers should consider infection with rapidly growing mycobacteria in patients who have surgical site infections unresponsive to standard treatment. PMID:27434822

  20. Multistate US Outbreak of Rapidly Growing Mycobacterial Infections Associated with Medical Tourism to the Dominican Republic, 2013–20141

    PubMed Central

    Esposito, Douglas H.; Gaines, Joanna; Ridpath, Alison; Barry, M. Anita; Feldman, Katherine A.; Mullins, Jocelyn; Burns, Rachel; Ahmad, Nina; Nyangoma, Edith N.; Nguyen, Duc B.; Perz, Joseph F.; Moulton-Meissner, Heather A.; Jensen, Bette J.; Lin, Ying; Posivak-Khouly, Leah; Jani, Nisha; Morgan, Oliver W.; Brunette, Gary W.; Pritchard, P. Scott; Greenbaum, Adena H.; Rhee, Susan M.; Blythe, David; Sotir, Mark

    2016-01-01

    During 2013, the Maryland Department of Health and Mental Hygiene in Baltimore, MD, USA, received report of 2 Maryland residents whose surgical sites were infected with rapidly growing mycobacteria after cosmetic procedures at a clinic (clinic A) in the Dominican Republic. A multistate investigation was initiated; a probable case was defined as a surgical site infection unresponsive to therapy in a patient who had undergone cosmetic surgery in the Dominican Republic. We identified 21 case-patients in 6 states who had surgery in 1 of 5 Dominican Republic clinics; 13 (62%) had surgery at clinic A. Isolates from 12 (92%) of those patients were culture-positive for Mycobacterium abscessus complex. Of 9 clinic A case-patients with available data, all required therapeutic surgical intervention, 8 (92%) were hospitalized, and 7 (78%) required ≥3 months of antibacterial drug therapy. Healthcare providers should consider infection with rapidly growing mycobacteria in patients who have surgical site infections unresponsive to standard treatment. PMID:27434822

  1. DNA-based methodologies for rapid detection, quantification, and species- or strain-level identification of respiratory pathogens (Mycobacteria and Pseudomonads) in metalworking fluids.

    PubMed

    Yadav, Jagjit S; Khan, Izhar U H; Fakhari, Farnaz; Soellner, Mathew B

    2003-11-01

    Mycobacteria and pseudomonads occurring in modern metalworking fluids (MWF) have been implicated in occupational health hazards as causal agents for hypersensitivity pneumonitis (HP) and other respiratory illnesses in machine workers exposed to these fluids and their aerosols. Unlike the conventional cultural and biochemical methods, which are often slow and ambiguous and detect only culturable cells, DNA-based methods offer a time-saving alternative for reliable detection and identification of both culturable and nonculturable bacteria in MWF and for selective quantification of individual genera of pathogens of interest in these fluids. This is the first report on DNA-based direct detection of mycobacteria and pseudomonads in MWF without culturing. Genus-specific PCR approach was successfully applied for screening of field MWF samples originating from different industrial users for detection of mycobacteria or pseudomonads including both culturable and nonculturable cells. PCR in combination with amplicon DNA sequencing led to the identification of Mycobacterium chelonae, Pseudomonas nitroreducens, and an undefined Pseudomonas species from these fluids. Genome fingerprinting by pulsed-field gel electrophoresis (PFGE) on Mycobacterium isolates further showed that the isolates represented three strains of M. chelonae although the possibility of one of the strains being clonal with M. immunogenum cannot be excluded. In parallel efforts, a quantitative competitive PCR method developed based on the Pseudomonas-specific PCR was applied to quantify total P. fluorescens cells in contaminated metalworking fluid and MWF aerosol without culturing. The DNA-based protocols developed in this study will allow rapid screening of field MWF samples for the presence of both culturable and nonculturable cells and thus facilitate effective fluid management and timely exposure assessment. PMID:14555451

  2. Rapid and accurate identification of Mycobacterium tuberculosis complex and common non-tuberculous mycobacteria by multiplex real-time PCR targeting different housekeeping genes.

    PubMed

    Nasr Esfahani, Bahram; Rezaei Yazdi, Hadi; Moghim, Sharareh; Ghasemian Safaei, Hajieh; Zarkesh Esfahani, Hamid

    2012-11-01

    Rapid and accurate identification of mycobacteria isolates from primary culture is important due to timely and appropriate antibiotic therapy. Conventional methods for identification of Mycobacterium species based on biochemical tests needs several weeks and may remain inconclusive. In this study, a novel multiplex real-time PCR was developed for rapid identification of Mycobacterium genus, Mycobacterium tuberculosis complex (MTC) and the most common non-tuberculosis mycobacteria species including M. abscessus, M. fortuitum, M. avium complex, M. kansasii, and the M. gordonae in three reaction tubes but under same PCR condition. Genetic targets for primer designing included the 16S rDNA gene, the dnaJ gene, the gyrB gene and internal transcribed spacer (ITS). Multiplex real-time PCR was setup with reference Mycobacterium strains and was subsequently tested with 66 clinical isolates. Results of multiplex real-time PCR were analyzed with melting curves and melting temperature (T (m)) of Mycobacterium genus, MTC, and each of non-tuberculosis Mycobacterium species were determined. Multiplex real-time PCR results were compared with amplification and sequencing of 16S-23S rDNA ITS for identification of Mycobacterium species. Sensitivity and specificity of designed primers were each 100 % for MTC, M. abscessus, M. fortuitum, M. avium complex, M. kansasii, and M. gordonae. Sensitivity and specificity of designed primer for genus Mycobacterium was 96 and 100 %, respectively. According to the obtained results, we conclude that this multiplex real-time PCR with melting curve analysis and these novel primers can be used for rapid and accurate identification of genus Mycobacterium, MTC, and the most common non-tuberculosis Mycobacterium species.

  3. 16S-23S Internal Transcribed Spacer Region PCR and Sequencer-Based Capillary Gel Electrophoresis has Potential as an Alternative to High Performance Liquid Chromatography for Identification of Slowly Growing Nontuberculous Mycobacteria

    PubMed Central

    Subedi, Shradha; Kong, Fanrong; Jelfs, Peter; Gray, Timothy J.; Xiao, Meng; Sintchenko, Vitali; Chen, Sharon C-A

    2016-01-01

    Accurate identification of slowly growing nontuberculous mycobacteria (SG-NTM) of clinical significance remains problematic. This study evaluated a novel method of SG-NTM identification by amplification of the mycobacterial 16S-23S rRNA internal transcribed spacer (ITS) region followed by resolution of amplified fragments by sequencer-based capillary gel electrophoresis (SCGE). Fourteen American Type Culture Collection (ATCC) strains and 103 clinical/environmental isolates (total n = 24 species) of SG-NTM were included. Identification was compared with that achieved by high performance liquid chromatography (HPLC), in-house PCR and 16S/ITS sequencing. Isolates of all species yielded a SCGE profile comprising a single fragment length (or peak) except for M. scrofulaceum (two peaks). SCGE peaks of ATCC strains were distinct except for peak overlap between Mycobacterium kansasii and M. marinum. Of clinical/environmental strains, unique peaks were seen for 7/17 (41%) species (M. haemophilum, M. kubicae, M. lentiflavum, M. terrae, M. kansasii, M. asiaticum and M. triplex); 3/17 (18%) species were identified by HPLC. There were five SCGE fragment length types (I–V) each of M. avium, M. intracellulare and M. gordonae. Overlap of fragment lengths was seen between M. marinum and M. ulcerans; for M. gordonae SCGE type III and M. paragordonae; M. avium SCGE types III and IV, and M. intracellulare SCGE type I; M. chimaera, M. parascrofulaceum and M. intracellulare SCGE types III and IV; M. branderi and M. avium type V; and M. vulneris and M. intracellulare type V. The ITS-SCGE method was able to provide the first line rapid and reproducible species identification/screening of SG-NTM and was more discriminatory than HPLC. PMID:27749897

  4. On the killing of mycobacteria by macrophages.

    PubMed

    Jordao, Luisa; Bleck, Christopher K E; Mayorga, Luis; Griffiths, Gareth; Anes, Elsa

    2008-02-01

    Both pathogenic and non-pathogenic mycobacteria are internalized into macrophage phagosomes. Whereas the non-pathogenic types are invariably killed by all macrophages, the pathogens generally survive and grow. Here, we addressed the survival, production of nitrogen intermediates (RNI) and intracellular trafficking of the non-pathogenic Mycobacterium smegmatis, the pathogen-like, BCG and the pathogenic M. bovis in different mouse, human and bovine macrophages. The bacteriocidal effects of RNI were restricted for all bacterial species to the early stages of infection. EM analysis showed clearly that all the mycobacteria remained within phagosomes even at late times of infection. The fraction of BCG and M. bovis found in mature phagolysosomes rarely exceeded 10% of total, irrespective of whether bacteria were growing, latent or being killed, with little correlation between the extent of phagosome maturation and the degree of killing. Theoretical modelling of our data identified two different potential sets of explanations that are consistent with our results. The model we favour is one in which a small but significant fraction of BCG is killed in an early phagosome, then maturation of a small fraction of phagosomes with both live and killed bacteria, followed by extremely rapid killing and digestion of the bacteria in phago-lysosomes.

  5. A Rapid and Sensitive Diagnostic Screening Assay for Detection of Mycobacteria Including Mycobacterium tuberculosis Directly from Sputum without Extraction.

    PubMed

    Cross, Lisa Jane; Anscombe, Catherine; McHugh, Timothy D; Abubakar, Ibrahim; Shorten, Robert John; Thorne, Nicola; Arnold, Cath

    2015-01-01

    We report a novel approach utilising a real-time PCR screening assay targeting a 53 bp tandemly repeated element present at various loci within the Mycobacterium tuberculosis (Mtb) genome. Positive samples were identified within a discriminatory melting curve range of 90-94°C, with results obtained in under one hour directly from decontaminated sputum samples without extraction. A panel of 89 smear-positive sputa were used for analytical validation of the assay with 100% concordance, with sensitivity matching that of culture. Cross reactivity was detected within a narrow range of mycobacteria other than tuberculosis (MOTT) (five sputa, three in silico), with the highest sensitivity within M. avium complex (MAC). A year-long head to head evaluation of the test with the GeneXpert platform was carried out with 104 consecutive samples at the Royal Free Hospital, UK. Receiver operating characteristics (ROC) analysis of the data revealed that the two tests are approximately equivalent in sensitivity, with the area under the curve being 0.85 and 0.80 for the GeneXpert and our assay, respectively, indicating that the test would be a cost effective screen prior to GeneXpert testing.

  6. Sliding Motility in Mycobacteria

    PubMed Central

    Martínez, Asunción; Torello, Sandra; Kolter, Roberto

    1999-01-01

    Mycobacteria are nonflagellated gram-positive microorganisms. Previously thought to be nonmotile, we show here that Mycobacterium smegmatis can spread on the surface of growth medium by a sliding mechanism. M. smegmatis spreads as a monolayer of cells which are arranged in pseudofilaments by close cell-to-cell contacts, predominantly along their longitudinal axis. The monolayer moves away from the inoculation point as a unit with only minor rearrangements. No extracellular structures such as pili or fimbriae appear to be involved in this process. The ability to translocate over the surface correlates with the presence of glycopeptidolipids, a mycobacterium-specific class of amphiphilic molecules located in the outermost layer of the cell envelope. We present evidence that surface motility is not restricted to M. smegmatis but is also a property of the slow-growing opportunistic pathogen M. avium. This form of motility could play an important role in surface colonization by mycobacteria in the environment as well as in the host. PMID:10572138

  7. Advantages of Using Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry as a Rapid Diagnostic Tool for Identification of Yeasts and Mycobacteria in the Clinical Microbiological Laboratory

    PubMed Central

    Chen, Jonathan H. K.; Yam, Wing-Cheong; Ngan, Antonio H. Y.; Fung, Ami M. Y.; Woo, Wai-Lan; Yan, Mei-Kum; Choi, Garnet K. Y.; Ho, Pak-Leung; Cheng, Vincent C. C.

    2013-01-01

    Yeast and mycobacteria can cause infections in immunocompromised patients and normal hosts. The rapid identification of these organisms can significantly improve patient care. There has been an increasing number of studies on using matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) for rapid yeast and mycobacterial identifications. However, studies on direct comparisons between the Bruker Biotyper and bioMérieux Vitek MS systems for the identification of yeast and mycobacteria have been limited. This study compared the performance of the two systems in their identification of 98 yeast and 102 mycobacteria isolates. Among the 98 yeast isolates, both systems generated species-level identifications in >70% of the specimens, of which Candida albicans was the most commonly cultured species. At a genus-level identification, the Biotyper system identified more isolates than the Vitek MS system for Candida (75/78 [96.2%]versus 68/78 [87.2%], respectively; P = 0.0426) and non-Candida yeasts (18/20 [90.0%]versus 7/20 [35.0%], respectively; P = 0.0008). For mycobacterial identification, the Biotyper system generated reliable identifications for 89 (87.3%) and 64 (62.8%) clinical isolates at the genus and species levels, respectively, from solid culture media, whereas the Vitek MS system did not generate any reliable identification. The MS method differentiated 12/21 clinical species, despite the fact that no differentiation between Mycobacterium abscessus and Mycobacterium chelonae was found by using 16S rRNA gene sequencing. In summary, the MALDI-TOF MS method provides short turnaround times and a standardized working protocol for the identification of yeast and mycobacteria. Our study demonstrates that MALDI-TOF MS is suitable as a first-line test for the identification of yeast and mycobacteria in clinical laboratories. PMID:24048537

  8. Glasses crystallize rapidly at free surfaces by growing crystals upward.

    PubMed

    Sun, Ye; Zhu, Lei; Kearns, Kenneth L; Ediger, Mark D; Yu, Lian

    2011-04-12

    The crystallization of glasses and amorphous solids is studied in many fields to understand the stability of amorphous materials, the fabrication of glass ceramics, and the mechanism of biomineralization. Recent studies have found that crystal growth in organic glasses can be orders of magnitude faster at the free surface than in the interior, a phenomenon potentially important for understanding glass crystallization in general. Current explanations differ for surface-enhanced crystal growth, including released tension and enhanced mobility at glass surfaces. We report here a feature of the phenomenon relevant for elucidating its mechanism: Despite their higher densities, surface crystals rise substantially above the glass surface as they grow laterally, without penetrating deep into the bulk. For indomethacin (IMC), an organic glass able to grow surface crystals in two polymorphs (α and γ), the growth front can be hundreds of nanometers above the glass surface. The process of surface crystal growth, meanwhile, is unperturbed by eliminating bulk material deeper than some threshold depth (ca. 300 nm for α IMC and less than 180 nm for γ IMC). As a growth strategy, the upward-lateral growth of surface crystals increases the system's surface energy, but can effectively take advantage of surface mobility and circumvent slow growth in the bulk.

  9. Intraoral tumor with rapid growing. Report of a case.

    PubMed

    González-Martín-Moro, Javier; Cebrián-Carretero, Jose Luis; Gómez-García, Elena; del Castillo-Pardo de Vera, Jose Luis; del Val, Daniel

    2005-01-01

    The appearance of an intraoral mass is common in our specialty. Most are benign lesions, but some are primary malignancies. Metastases account for less than 1% of all oral malignancies. An 86 year old woman was referred to our department with a large, asymptomatic, intraoral, fast-growing mass. She had no previous cancer history or other relevant physical findings. The radiology studies showed underlying bone erosion. The histological study showed a metastatic adenocarcinoma with a suspected origin in the abdomen. We were unable to identify it by non invasive diagnostic procedures. Given the patient's general status and despite the ominous prognosis of such lesions, we decided not to perform any aggressive therapy beyond removing the oral mass, in order to maintain her quality of life. There have been no local recurrences until this time.

  10. Susceptibility Testing of Antibiotics That Degrade Faster than the Doubling Time of Slow-Growing Mycobacteria: Ertapenem Sterilizing Effect versus Mycobacterium tuberculosis.

    PubMed

    Srivastava, Shashikant; van Rijn, Sander P; Wessels, A Mireille A; Alffenaar, Jan-Willem C; Gumbo, Tawanda

    2016-05-01

    Drug susceptibility tests (DSTs) for Mycobacterium tuberculosis require at least 7 days of incubation. Drugs that are unstable at 37°C, such as ertapenem, are likely to be degraded before killing or inhibiting slow-growing bacteria. This would alter the MICs of these drugs, including ertapenem, leading to falsely high MICs. Here, we describe a new strategy we developed to perform DSTs and measure MICs for such unstable compounds. PMID:26926650

  11. In Vitro Antimicrobial Susceptibility of Nontuberculous Mycobacteria in Iran.

    PubMed

    Heidarieh, Parvin; Mirsaeidi, Mehdi; Hashemzadeh, Mohamad; Feizabadi, Mohamad Mehdi; Bostanabad, Saeed Zaker; Nobar, Mostafa Ghalami; Hashemi Shahraki, Abodolrazagh

    2016-03-01

    Many species of nontuberculous mycobacteria (NTM) have long been identified as important causes of human disease, the incidence of which is rising. Several reports have suggested increasing trend of both in vitro and in vivo resistance to available treatment regimes. The aim of this study was to evaluate antibiotic susceptibility of clinically relevant NTM isolates using standard microbroth dilution test. Antimicrobial susceptibility testing was performed following National Committee for Clinical Laboratory Standards methods for NTM isolates, including 85 Mycobacterium fortuitum, 39 Mycobacterium chelonae, and 30 Mycobacterium abscessus subsp. abscessus as rapidly growing mycobacteria and 48 Mycobacterium simiae and 40 Mycobacterium kansasii as slowly growing mycobacteria. All isolates were recovered from various types of clinical samples and identified by multilocus sequence analysis. Trimethoprim-sulfamethoxazole (TMP-SMZ), amikacin, tobramycin, clarithromycin, moxifloxacin, linezolid, and imipenem showed better activity against M. fortuitum rather than meropenem, ciprofloxacin, cefoxitin, and doxycycline. Amikacin was active against 93% of M. abscessus subsp. abscessus. Linezolid, clarithromycin, cefoxitin, ciprofloxacin, imipenem, moxifloxacin, tobramycin, TMP-SMZ, doxycycline, and meropenem showed some activities on M. abscessus subsp. abscessus as well. The majority of M. abscessus subsp. abscessus and M. chelonae strains were multidrug resistant. Among the 40 isolates of M. kansasii, all were susceptible to ethambutol, isoniazid, clarithromycin, moxifloxacin, and linezolid. These isolates were also resistant to doxycycline and 50% were resistant to rifampicin and ciprofloxacin. M. simiae was resistant to clarithromycin, doxycycline, isoniazid, and TMP-SMZ, and the majority of isolates showed high levels of resistance to linezolid, ethambutol, ciprofloxacin, streptomycin, and rifampicin. The majority of M. simiae isolates were multidrug resistant. Our data

  12. [Differential growth inhibition of mycobacteria by interferon-gamma-or tumor necrosis factor-alpha-treated murine peritoneal macrophages].

    PubMed

    Sato, K; Tomioka, H; Saito, H

    1996-11-01

    Growth inhibition of the intracellular mycobacteria such as Mycobacterium tuberculosis, M. bovis, M. kansasii, M. avium, M. intracellulare, M. fortuitum, and M. chelonae subsp. abscessus by interferon-gamma (IFN-gamma)- or tumor necrosis factor-alpha (TNF-alpha)-treated murine peritoneal macrophages elicited by proteose peptone was studied in vitro. Macrophages were infected with slowly growing mycobacteria and the extracellular mycobacteria were washed out. Then, macrophages were treated with IFN-gamma or TNF-alpha at a concentration of 10 to 1000 U/ml for 2 days. In another experiment, macrophages were pretreated with these cytokines for 1 day then infected with rapidly growing mycobacteria as before. Macrophages were cultured with or without IFN-gamma or TNF-alpha for additional day. Mycobacterial growth was assessed by determination of colony-forming units on 7H11 agar plates after destruction of the macrophages. Stimulation of macrophages with IFN-gamma reduced the growth of mycobacteria. However, except for M. tuberculosis and M. bovis, growth was not inhibited by macrophages treated with TNF-alpha. IFN-gamma seems to be an important cytokine for the activation of mycobactericidal mechanisms in murine macrophages. Stimulation with IFN-gamma or TNF-alpha and subsequent phagocytosis of M. tuberculosis or M. intracellulare increased O2- production, which was assayed by the method of cytochrome C reduction by murine peritoneal macrophages. Phorbol myristate acetate-triggered-O2- production was also elevated by the cytokine pretreatment of the macrophages, suggesting that mycobacterial growth inhibition did not parallel the production of reactive oxygen intermediates in TNF alpha-activated murine peritoneal macrophages. These data suggest that bactericidal mechanisms of murine macrophages against nontuberculous mycobacteria may not depend on reactive oxygen intermediates. PMID:8958673

  13. The genomics of mycobacteria.

    PubMed

    Viale, M N; Zumárraga, M J; Araújo, F R; Zarraga, A M; Cataldi, A A; Romano, M I; Bigi, F

    2016-04-01

    The species Mycobacterium bovis and Mycobacterium avium subspecies paratuberculosis are the causal agents, respectively, of tuberculosis and paratuberculosis in animals. Both mycobacteria, especially M. bovis, are also important to public health because they can infect humans. In recent years, this and the impact of tuberculosis and paratuberculosis on animal production have led to significant advances in knowledge about both pathogens and their host interactions. This article describes the contribution of genomics and functional genomics to studies of the evolution, virulence, epidemiology and diagnosis of both these pathogenic mycobacteria. PMID:27217180

  14. The genomics of mycobacteria.

    PubMed

    Viale, M N; Zumárraga, M J; Araújo, F R; Zarraga, A M; Cataldi, A A; Romano, M I; Bigi, F

    2016-04-01

    The species Mycobacterium bovis and Mycobacterium avium subspecies paratuberculosis are the causal agents, respectively, of tuberculosis and paratuberculosis in animals. Both mycobacteria, especially M. bovis, are also important to public health because they can infect humans. In recent years, this and the impact of tuberculosis and paratuberculosis on animal production have led to significant advances in knowledge about both pathogens and their host interactions. This article describes the contribution of genomics and functional genomics to studies of the evolution, virulence, epidemiology and diagnosis of both these pathogenic mycobacteria.

  15. Vibrio natriegens: A Rapidly Growing Micro-Organism Ideally Suited for Class Experiments

    ERIC Educational Resources Information Center

    Mullenger, L.; Gill, Nijole R.

    1973-01-01

    Describes five microbiological experiments using the marine organism Vibrio natriegens. This organism is highly suitable for laboratory work because it is non-pathogenic and grows extremely rapidly, having the distinction of the lowest mean generation time yet recorded (9.8 minutes). (JR)

  16. Public Relations in Rapidly Growing Suburban Districts: Insights from Texas Superintendents Bonny Cain and Doug Otto

    ERIC Educational Resources Information Center

    Decman, John M.

    2005-01-01

    Throughout Texas, enrollments in suburban school districts have been rising, and in some instances, the increases have been substantial. Causes of this demographic trend are multifaceted, but in most instances they are an intricate mix of state population growth and urban flight. Rapidly growing suburban districts, like all Texas districts,…

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

    PubMed

    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.

  18. Atypical presentation of atypical mycobacteria in atypical diabetes

    PubMed Central

    Biswas, Sugata Narayan; Chakraborty, Partha Pratim; Satpathi, Partha Sarathi; Patra, Shinjan

    2016-01-01

    A 45-year-old, non-obese male presented with low-grade, remittent fever and a fluctuant swelling over the posterior aspect of his lower left flank. Laboratory tests revealed leukocytosis, raised ESR, hyperglycemia and raised HbA1C levels. Light microscopy of Ziehl–Neelsen-stained pus sample revealed numerous acid-fast bacilli. After 72 h of incubating aspirated pus in Löwenstein–Jensen media, non-pigmented, cream-colored colonies were observed, suggestive of rapid-growing atypical forms of mycobacteria. Polymerase chain reaction of isolated bacteria identified Mycobacterium chelonae as causative organism. Abdominal skiagram revealed extensive pancreatic intraductal calcifications suggestive of fibrocalculous pancreatic diabetes and lumbar vertebral body destruction with evidence of paravertebral abscess. The patient was prescribed a split-mixed insulin regimen, clarithromycin and ciprofloxacin with complete resolution of the subcutaneous abscess at 6 months. Diabetic patients are prone to infections. Mycobacteria, especially atypical ones, involving the spine and subcutaneous tissues have rarely been reported. PMID:27127641

  19. Pulmonary Disease Caused by Non-Tuberculous Mycobacteria.

    PubMed

    Wassilew, Nasstasja; Hoffmann, Harald; Andrejak, Claire; Lange, Christoph

    2016-01-01

    Non-tuberculous mycobacteria (NTM) include more than 160 ubiquitous, environmental, acid-fast-staining bacterial species, some of which may cause disease in humans. Chronic pulmonary infection is the most common clinical manifestation. Although patients suffering from chronic lung diseases are particularly susceptible to NTM pulmonary disease, many affected patients have no apparent risk factors. Host and pathogen factors leading to NTM pulmonary disease are not well understood and preventive therapies are lacking. NTM isolation and pulmonary disease are reported to rise in frequency in Europe as well as in other parts of the world. Differentiation between contamination, infection, and disease remains challenging. Treatment of NTM pulmonary disease is arduous, lengthy, and costly. Correlations between results of in vitro antibiotic susceptibility testing and clinical treatment outcomes are only evident for the Mycobacterium avium complex, M. kansasii, and some rapidly growing mycobacteria. We describe the epidemiology of NTM pulmonary disease as well as emerging NTM pathogens and their geographical distribution in non-cystic fibrosis patients in Europe. We also review recent innovations for the diagnosis of NTM pulmonary disease, summarize treatment recommendations, and identify future research priorities to improve the management of patients affected by NTM pulmonary disease. PMID:27207809

  20. Factors Affecting Phage D29 Infection: A Tool to Investigate Different Growth States of Mycobacteria

    PubMed Central

    Swift, Benjamin M. C.; Gerrard, Zara E.; Huxley, Jonathan N.; Rees, Catherine E. D.

    2014-01-01

    Bacteriophages D29 and TM4 are able to infect a wide range of mycobacteria, including pathogenic and non-pathogenic species. Successful phage infection of both fast- and slow-growing mycobacteria can be rapidly detected using the phage amplification assay. Using this method, the effect of oxygen limitation during culture of mycobacteria on the success of phage infection was studied. Both D29 and TM4 were able to infect cultures of M. smegmatis and Mycobacterium avium subspecies paratuberculosis (MAP) grown in liquid with aeration. However when cultures were grown under oxygen limiting conditions, only TM4 could productively infect the cells. Cell attachment assays showed that D29 could bind to the cells surface but did not complete the lytic cycle. The ability of D29 to productively infect the cells was rapidly recovered (within 1 day) when the cultures were returned to an aerobic environment and this recovery required de novo RNA synthesis. These results indicated that under oxygen limiting conditions the cells are entering a growth state which inhibits phage D29 replication, and this change in host cell biology which can be detected by using both phage D29 and TM4 in the phage amplification assay. PMID:25184428

  1. Rapidly growing pigmented tumor on a scalp nevus sebaceous of a pediatric patient: Observation or excision.

    PubMed

    Gaitan-Gaona, Francisco; Said, Mirra C; Galvan-Linares, Aldo; Palafox-Vigil, Gloria; Valdes-Rodriguez, Rodrigo

    2014-07-15

    A 14-year-old girl presented with a new, rapidly growing, pigmented tumor on a previously existing yellowish, verrucous plaque on the scalp. The patient received complete surgical excision. Routine histology ruled out basal cell carcinoma (BCC) and the histological diagnosis was pigmented trichoblastoma arising in nevus sebaceous (NS). It is important to define management for new lesions developing in pediatric patients with existing nevus sebaceus.

  2. Energetics of Respiration and Oxidative Phosphorylation in Mycobacteria

    PubMed Central

    Hards, Kiel; Vilchèze, Catherine; Hartman, Travis; Berney, Michael

    2014-01-01

    Mycobacteria inhabit a wide range of intracellular and extracellular environments. Many of these environments are highly dynamic and therefore mycobacteria are faced with the constant challenge of redirecting their metabolic activity to be commensurate with either replicative growth or a non-replicative quiescence. A fundamental feature in this adaptation is the ability of mycobacteria to respire, regenerate reducing equivalents and generate ATP via oxidative phosphorylation. Mycobacteria harbor multiple primary dehydrogenases to fuel the electron transport chain and two terminal respiratory oxidases, an aa3-type cytochrome c oxidase and cytochrome bd-type menaquinol oxidase, are present for dioxygen reduction coupled to the generation of a protonmotive force. Hypoxia leads to the downregulation of key respiratory complexes, but the molecular mechanisms regulating this expression are unknown. Despite being obligate aerobes, mycobacteria have the ability to metabolize in the absence of oxygen and a number of reductases are present to facilitate the turnover of reducing equivalents under these conditions (e.g. nitrate reductase, succinate dehydrogenase/fumarate reductase). Hydrogenases and ferredoxins are also present in the genomes of mycobacteria suggesting the ability of these bacteria to adapt to an anaerobic-type of metabolism in the absence of oxygen. ATP synthesis by the membrane-bound F1FO-ATP synthase is essential for growing and non-growing mycobacteria and the enzyme is able to function over a wide range of protonmotive force values (aerobic to hypoxic). The discovery of lead compounds that target respiration and oxidative phosphorylation in Mycobacterium tuberculosis highlights the importance of this area for the generation of new front line drugs to combat tuberculosis. PMID:25346874

  3. Energetics of Respiration and Oxidative Phosphorylation in Mycobacteria.

    PubMed

    Cook, Gregory M; Hards, Kiel; Vilchèze, Catherine; Hartman, Travis; Berney, Michael

    2014-06-01

    Mycobacteria inhabit a wide range of intracellular and extracellular environments. Many of these environments are highly dynamic and therefore mycobacteria are faced with the constant challenge of redirecting their metabolic activity to be commensurate with either replicative growth or a non-replicative quiescence. A fundamental feature in this adaptation is the ability of mycobacteria to respire, regenerate reducing equivalents and generate ATP via oxidative phosphorylation. Mycobacteria harbor multiple primary dehydrogenases to fuel the electron transport chain and two terminal respiratory oxidases, an aa3 -type cytochrome c oxidase and cytochrome bd-type menaquinol oxidase, are present for dioxygen reduction coupled to the generation of a protonmotive force. Hypoxia leads to the downregulation of key respiratory complexes, but the molecular mechanisms regulating this expression are unknown. Despite being obligate aerobes, mycobacteria have the ability to metabolize in the absence of oxygen and a number of reductases are present to facilitate the turnover of reducing equivalents under these conditions (e.g. nitrate reductase, succinate dehydrogenase/fumarate reductase). Hydrogenases and ferredoxins are also present in the genomes of mycobacteria suggesting the ability of these bacteria to adapt to an anaerobic-type of metabolism in the absence of oxygen. ATP synthesis by the membrane-bound F1FO-ATP synthase is essential for growing and non-growing mycobacteria and the enzyme is able to function over a wide range of protonmotive force values (aerobic to hypoxic). The discovery of lead compounds that target respiration and oxidative phosphorylation in Mycobacterium tuberculosis highlights the importance of this area for the generation of new front line drugs to combat tuberculosis. PMID:25346874

  4. Sulfate metabolism in mycobacteria.

    PubMed

    Schelle, Michael W; Bertozzi, Carolyn R

    2006-10-01

    Pathogenic bacteria have developed numerous mechanisms to survive inside a hostile host environment. The human pathogen Mycobacterium tuberculosis (M. tb) is thought to control the human immune response with diverse biomolecules, including a variety of exotic lipids. One prevalent M. tb-specific sulfated metabolite, termed sulfolipid-1 (SL-1), has been correlated with virulence though its specific biological function is not known. Recent advances in our understanding of SL-1 biosynthesis will help elucidate the role of this curious metabolite in M. tb infection. Furthermore, the study of SL-1 has led to questions regarding the significance of sulfation in mycobacteria. Examples of sulfated metabolites as mediators of interactions between bacteria and plants suggest that sulfation is a key modulator of extracellular signaling between prokaryotes and eukaryotes. The discovery of novel sulfated metabolites in M. tb and related mycobacteria strengthens this hypothesis. Finally, mechanistic and structural data from sulfate-assimilation enzymes have revealed how M. tb controls the flux of sulfate in the cell. Mutants with defects in sulfate assimilation indicate that the fate of sulfur in M. tb is a critical survival determinant for the bacteria during infection and suggest novel targets for tuberculosis drug therapy.

  5. Nontuberculous mycobacteria in respiratory infections: advances in diagnosis and identification.

    PubMed

    Somoskovi, Akos; Salfinger, Max

    2014-06-01

    An urgent question that needs to be addressed rapidly by the mycobacteriology laboratory is whether Mycobacterium tuberculosis complex or NTM is involved. NAA assays are excellent tools for the purpose, and can be used directly on the clinical specimens of patients suspected of having mycobacterial disease, allowing same-day reporting of results. The CDC recommends using both liquid and solid media for growth detection of mycobacteria to decrease the time to detection and to increase the yield of growth detection. DNA sequencing of variable genomic regions offers a rapid, accurate, and relatively inexpensive method for the identification of mycobacteria.

  6. Learn about Nontuberculous Mycobacteria (NTM)

    MedlinePlus

    ... are naturally-occurring organisms found in water and soil. NTM lung infection occurs when a person inhales ... Nontuberculous mycobacteria (NTM) are organisms naturally found in soil and water. NTM infections can become chronic and ...

  7. Animal Models of Mycobacteria Infection

    PubMed Central

    Ordway, Diane J.; Orme, Ian M.

    2011-01-01

    This unit describes the infection of mice and guinea pigs with mycobacteria via various routes, as well as necropsy methods for the determination of mycobacterial loads within target organs. Additionally, methods for cultivating mycobacteria and preparing stocks are described. The protocols outlined are primarily used for M. tuberculosis, but can also be used for the study of other non-tuberculosis mycobacterial species. PMID:18432756

  8. Night Temperature has a Minimal Effect on Respiration and Growth in Rapidly Growing Plants

    PubMed Central

    FRANTZ, JONATHAN M.; COMETTI, NILTON N.; BUGBEE, BRUCE

    2004-01-01

    • Background and Aims Carbon gain depends on efficient photosynthesis and adequate respiration. The effect of temperature on photosynthetic efficiency is well understood. In contrast, the temperature response of respiration is based almost entirely on short‐term (hours) measurements in mature organisms to develop Q10 values for maintenance and whole‐plant respiration. These Q10 values are then used to extrapolate across whole life cycles to predict the influence of temperature on plant growth. • Methods In this study, night temperature in young, rapidly growing plant communities was altered from 17 to 34 °C for up to 20 d. Day temperature was maintained at 25 °C. CO2 gas‐exchange was continuously monitored in ten separate chambers to quantify the effect of night‐temperature on respiration, photosynthesis and the efficiency of carbon gain (carbon use efficiency). • Key Results Respiration increased only 20–46 % for each 10 °C rise in temperature (total respiratory Q10 of between 1·2 to about 1·5). This change resulted in only a 2–12 % change in carbon use efficiency, and there was no effect on cumulative carbon gain or dry mass. No acclimation of respiration was observed after 20 d of treatment. • Conclusions These findings indicate that whole‐plant respiration of rapidly growing plants has a small sensitivity to temperature, and that the sensitivity does not change among the species tested, even after 20 d of treatment. Finally, the results support respiration models that separate respiration into growth and maintenance components. PMID:15159217

  9. Rapid urbanization and the growing threat of violence and conflict: a 21st century crisis.

    PubMed

    Patel, Ronak B; Burkle, Frederick M

    2012-04-01

    As the global population is concentrated into complex environments, rapid urbanization increases the threat of conflict and insecurity. Many fast-growing cities create conditions of significant disparities in standards of living, which set up a natural environment for conflict over resources. As urban slums become a haven for criminal elements, youth gangs, and the arms trade, they also create insecurity for much of the population. Specific populations, such as women, migrants, and refugees, bear the brunt of this lack of security, with significant impacts on their livelihoods, health, and access to basic services. This lack of security and violence also has great costs to the general population, both economic and social. Cities have increasingly become the battlefield of recent conflicts as they serve as the seats of power and gateways to resources. International agencies, non-governmental organizations, and policy-makers must act to stem this tide of growing urban insecurity. Protecting urban populations and preventing future conflict will require better urban planning, investment in livelihood programs for youth, cooperation with local communities, enhanced policing, and strengthening the capacity of judicial systems.

  10. Aquaculture: a rapidly growing and significant source of sustainable food? Status, transitions and potential.

    PubMed

    Little, D C; Newton, R W; Beveridge, M C M

    2016-08-01

    The status and potential of aquaculture is considered as part of a broader food landscape of wild aquatic and terrestrial food sources. The rationale and resource base required for the development of aquaculture are considered in the context of broader societal development, cultural preferences and human needs. Attention is drawn to the uneven development and current importance of aquaculture globally as well as its considerable heterogeneity of form and function compared with established terrestrial livestock production. The recent drivers of growth in demand and production are examined and the persistent linkages between exploitation of wild stocks, full life cycle culture and the various intermediate forms explored. An emergent trend for sourcing aquaculture feeds from alternatives to marine ingredients is described and the implications for the sector with rapidly growing feed needs discussed. The rise of non-conventional and innovative feed ingredients, often shared with terrestrial livestock, are considered, including aquaculture itself becoming a major source of marine ingredients. The implications for the continued expected growth of aquaculture are set in the context of sustainable intensification, with the challenges that conventional intensification and emergent integration within, and between, value chains explored. The review concludes with a consideration of the implications for dependent livelihoods and projections for various futures based on limited resources but growing demand.

  11. Rapid urbanization and the growing threat of violence and conflict: a 21st century crisis.

    PubMed

    Patel, Ronak B; Burkle, Frederick M

    2012-04-01

    As the global population is concentrated into complex environments, rapid urbanization increases the threat of conflict and insecurity. Many fast-growing cities create conditions of significant disparities in standards of living, which set up a natural environment for conflict over resources. As urban slums become a haven for criminal elements, youth gangs, and the arms trade, they also create insecurity for much of the population. Specific populations, such as women, migrants, and refugees, bear the brunt of this lack of security, with significant impacts on their livelihoods, health, and access to basic services. This lack of security and violence also has great costs to the general population, both economic and social. Cities have increasingly become the battlefield of recent conflicts as they serve as the seats of power and gateways to resources. International agencies, non-governmental organizations, and policy-makers must act to stem this tide of growing urban insecurity. Protecting urban populations and preventing future conflict will require better urban planning, investment in livelihood programs for youth, cooperation with local communities, enhanced policing, and strengthening the capacity of judicial systems. PMID:22591767

  12. Cancer survivors in Switzerland: a rapidly growing population to care for

    PubMed Central

    2013-01-01

    Background Cancer survivors are a heterogeneous group with complex health problems. Data concerning its total number and growing dynamics for Switzerland are scarce and outdated. Methods Population and mortality data were retrieved from the Swiss Federal Statistical Office (FSO). Incidence and relative survival for invasive cancers were computed using data from the cancer registries Geneva (1970–2009), St. Gallen - Appenzell (1980–2010), Grisons & Glarus (1989–2010), and Valais (1989–2010). We estimated prevalence for 1990–2010 using the Prevalence, Incidence Approach MODel (PIAMOD) method. We calculated trends in prevalence estimates by Joinpoint analysis. Projections were extrapolated using the above models and based on time trends of the period 2007–2010. Results The estimated number of cancer survivors increased from 139′717 in 1990 (2.08% of the population) to 289′797 persons in 2010 (3.70%). The growth rate shows an exponential shape and was 3.3% per year in the period 2008 to 2010. Almost half of the survivors have a history of breast, prostate or colorectal cancer. Among cancer survivors, 55% are women but the increases have been more marked in men (p < 0.01, 3.9% annual increase in men vs. 2.7% in women since 2008). By the end of 2020 372′000 cancer survivors are expected to live in Switzerland. Conclusions There is a rapidly growing population of cancer survivors in Switzerland whose needs and concerns are largely unknown. PMID:23764068

  13. Aquaculture: a rapidly growing and significant source of sustainable food? Status, transitions and potential.

    PubMed

    Little, D C; Newton, R W; Beveridge, M C M

    2016-08-01

    The status and potential of aquaculture is considered as part of a broader food landscape of wild aquatic and terrestrial food sources. The rationale and resource base required for the development of aquaculture are considered in the context of broader societal development, cultural preferences and human needs. Attention is drawn to the uneven development and current importance of aquaculture globally as well as its considerable heterogeneity of form and function compared with established terrestrial livestock production. The recent drivers of growth in demand and production are examined and the persistent linkages between exploitation of wild stocks, full life cycle culture and the various intermediate forms explored. An emergent trend for sourcing aquaculture feeds from alternatives to marine ingredients is described and the implications for the sector with rapidly growing feed needs discussed. The rise of non-conventional and innovative feed ingredients, often shared with terrestrial livestock, are considered, including aquaculture itself becoming a major source of marine ingredients. The implications for the continued expected growth of aquaculture are set in the context of sustainable intensification, with the challenges that conventional intensification and emergent integration within, and between, value chains explored. The review concludes with a consideration of the implications for dependent livelihoods and projections for various futures based on limited resources but growing demand. PMID:27476856

  14. Cathepsin K inhibitors increase distal femoral bone mineral density in rapidly growing rabbits

    PubMed Central

    2013-01-01

    Background Selective and reversible inhibitors of human Cathepsin K (CatK), including odanacatib (ODN), have been developed as potential therapeutics for the treatment of osteoporosis. Inhibitors of human CatK show significantly less potency for the rodent enzymes compared with that for the human or rabbit enzymes; thus the Schenk model in growing rabbit was developed as a screening assay for the in vivo activity of CatK inhibitors in blocking bone resorption. Methods In this study, the efficacy of the selective inhibitors L-833905, L-006235, L-873724, and L-1037536 (ODN) of human CatK in the rapidly growing rabbit ‘Schenk’ model (age seven weeks) was compared to vehicle, using the bisphosphonate, alendronate (ALN), as a positive control, to assess inhibition of bone resorption. An enzyme inhibition assay (EIA) and an in vitro bone resorption assay using rabbit osteoclasts on bovine cortical bone slices were performed to evaluate the potency of these CatK inhibitors. Bone mineral density of the distal femur (DFBMD) was measured after ten days of treatment using ex vivo DXA densitometry. Results Results of the EIA using rabbit CatK and the rabbit bone resorption assay showed that three of the four compounds (L-006235, L-873724, and ODN) had similar potencies in the reduction of collagen degradation. L-833905 appeared to be a weaker inhibitor of CatK. Taking into account the respective in vitro potencies and pharmacokinetic profiles via oral administration, the efficacy of these four CatK inhibitors was demonstrated in a dose-related manner in the growing rabbit. Significant increases in DFBMD in animals dosed with the CatK inhibitors compared to vehicle were seen. Conclusions Efficacy of the CatK inhibitors in the Schenk rabbit correlated well with that in the in vitro rabbit bone resorption assay and in the ovariectomized rabbit model as previously published. Hence, these studies validated the rabbit Schenk assay as a rapid and reliable in vivo model for

  15. Intra-urban air pollution in a rapidly growing Sahelian city.

    PubMed

    Lindén, J; Boman, J; Holmer, B; Thorsson, S; Eliasson, I

    2012-04-01

    In this paper we analyze spatial and temporal variations of air pollution (PM(1), PM(2.5), PM(10), CO, NO(x), O(3), Toluene and Benzene) and climate in areas of different development typology in Ouagadougou, Burkina Faso. Analyses are based on measurements from fixed sites and car traverse measurements during field studies in 2007 and 2010. Large spatial and temporal variations were found, showing a generally poor air quality situation, with extreme levels of PM(10), commonly exceeding air quality guidelines of WHO. Pollution levels increase considerably with increased atmospheric stability. Important sources were transported dust and re-suspension of dust from unpaved roads, but also traffic emissions and biomass burning. The spatial variations are examined with focus on effects for variations in potential exposure depending on for example area of residence and daily activity pattern, showing that great differences are likely to exist. Ouagadougou, like most developing countries worldwide, currently experiences an extremely rapid population growth in combination with limited financial means. This is likely to create increasingly harmful air pollution situations for the rapidly growing populations of these areas, and shows an urgent need for increased understanding of the pollution situation as well as development of mitigation strategies.

  16. Comparison of Mycobacterial Growth Indicator Tube with Culture on RGM Selective Agar for Detection of Mycobacteria in Sputum Samples from Patients with Cystic Fibrosis.

    PubMed

    Eltringham, Ian; Pickering, Julie; Gough, Helen; Preece, Clair L; Perry, John D

    2016-08-01

    Nontuberculous mycobacteria (NTM) are an important cause of pulmonary disease in patients with cystic fibrosis (CF). A new culture medium (RGM medium) for the isolation of rapidly growing mycobacteria from the sputum of cystic fibrosis patients has recently been reported. The aim of this study was to compare culture of sputum samples on RGM medium with culture using a standard automated liquid culture method. Sputum samples were obtained from 187 distinct patients with CF attending King's College Hospital, London, United Kingdom. Each sample was decontaminated with 3% oxalic acid and inoculated into a mycobacterial growth indicator tube (MGIT) that was monitored for 42 days using the Bactec MGIT 960 instrument. Each sample was also cultured, without decontamination, onto RGM medium, which was incubated for 10 days at 30°C. Mycobacteria were isolated from 28 patients (prevalence, 15%). Mycobacteria were detected in 24 samples (86%) using the MGIT and in 23 samples (82%) using RGM medium (P = 1.00). In this setting, RGM medium showed sensitivity equivalent to that of the MGIT for isolation of NTM from the sputum of patients with CF. RGM medium offers a simple, convenient tool that can be embedded into routine culture methods, allowing the culture of all sputum samples that are submitted from patients with CF.

  17. Comparison of Mycobacterial Growth Indicator Tube with Culture on RGM Selective Agar for Detection of Mycobacteria in Sputum Samples from Patients with Cystic Fibrosis.

    PubMed

    Eltringham, Ian; Pickering, Julie; Gough, Helen; Preece, Clair L; Perry, John D

    2016-08-01

    Nontuberculous mycobacteria (NTM) are an important cause of pulmonary disease in patients with cystic fibrosis (CF). A new culture medium (RGM medium) for the isolation of rapidly growing mycobacteria from the sputum of cystic fibrosis patients has recently been reported. The aim of this study was to compare culture of sputum samples on RGM medium with culture using a standard automated liquid culture method. Sputum samples were obtained from 187 distinct patients with CF attending King's College Hospital, London, United Kingdom. Each sample was decontaminated with 3% oxalic acid and inoculated into a mycobacterial growth indicator tube (MGIT) that was monitored for 42 days using the Bactec MGIT 960 instrument. Each sample was also cultured, without decontamination, onto RGM medium, which was incubated for 10 days at 30°C. Mycobacteria were isolated from 28 patients (prevalence, 15%). Mycobacteria were detected in 24 samples (86%) using the MGIT and in 23 samples (82%) using RGM medium (P = 1.00). In this setting, RGM medium showed sensitivity equivalent to that of the MGIT for isolation of NTM from the sputum of patients with CF. RGM medium offers a simple, convenient tool that can be embedded into routine culture methods, allowing the culture of all sputum samples that are submitted from patients with CF. PMID:27225412

  18. Molecular typing of Iranian mycobacteria isolates by polymerase chain reaction-restriction fragment length polymorphism analysis of 360-bp rpoB gene

    PubMed Central

    Hadifar, Shima; Moghim, Sharareh; Fazeli, Hossein; GhasemianSafaei, Hajieh; Havaei, Seyed Asghar; Farid, Fariba; Esfahani, Bahram Nasr

    2015-01-01

    Background: Diagnosis and typing of Mycobacterium genus provides basic tools for investigating the epidemiology and pathogenesis of this group of bacteria. Polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis (PRA) is an accurate method providing diagnosis and typing of species of mycobacteria. The present study is conducted by the purpose of determining restriction fragment profiles of common types of mycobacteria by PRA method of rpoB gene in this geographical region. Materials and Methods: Totally 60 clinical and environmental isolates from February to October, 2013 were collected and subcultured and identified by phenotypic methods. A 360 bp fragment of the rpoB gene amplified by PCR and products were digested by MspI and HaeIII enzymes. Results: In the present study, of all mycobacteria isolates identified by PRA method, 13 isolates (21.66%) were Mycobacterium tuberculosis, 34 isolates (56.66%) were rapidly growing Nontuberculosis Mycobacteria (NTM) that including 26 clinical isolates (43.33%) and 8 environmental isolates (13.33%), 11 isolates (18.33%) were clinical slowly growing NTM. among the clinical NTM isolates, Mycobacterium fortuitum Type I with the frequency of 57.77% was the most prevalent type isolates. Furthermore, an unrecorded of the PRA pattern of Mycobacterium conceptionense (HeaIII: 120/90/80, MspI: 120/105/80) was found. This study demonstrated that the PRA method was high discriminatory power for identification and typing of mycobacteria species and was able to identify 96.6% of all isolates. Conclusion: Based on the result of this study, rpoB gene could be a potentially useful tool for identification and investigation of molecular epidemiology of mycobacterial species. PMID:26380237

  19. Rapidly growing tropical trees mobilize remarkable amounts of nitrogen, in ways that differ surprisingly among species.

    PubMed

    Russell, Ann E; Raich, James W

    2012-06-26

    Fast-growing forests such as tropical secondary forests can accumulate large amounts of carbon (C), and thereby play an important role in the atmospheric CO(2) balance. Because nitrogen (N) cycling is inextricably linked with C cycling, the question becomes: Where does the N come from to match high rates of C accumulation? In unique experimental 16-y-old plantations established in abandoned pasture in lowland Costa Rica, we used a mass-balance approach to quantify N accumulation in vegetation, identify sources of N, and evaluate differences among tree species in N cycling. The replicated design contained four broad-leaved evergreen tree species growing under similar environmental conditions. Nitrogen uptake was rapid, reaching 409 (± 30) kg · ha(-1) · y(-1), double the rate reported from a Puerto Rican forest and greater than four times that observed at Hubbard Brook Forest (New Hampshire, USA). Nitrogen amassed in vegetation was 874 (± 176) kg · ha(-1), whereas net losses of soil N (0-100 cm) varied from 217 (±146) to 3,354 (± 915) kg · ha(-1) (P = 0.018) over 16 y. Soil C:N, δ(13)C values, and N budgets indicated that soil was the main source of biomass N. In Vochysia guatemalensis, however, N fixation contributed >60 kg · ha(-1) · y(-1). All species apparently promoted soil N turnover, such that the soil N mean residence time was 32-54 y, an order of magnitude lower than the global mean. High rates of N uptake were associated with substantial N losses in three of the species, in which an average of 1.6 g N was lost for every gram of N accumulated in biomass.

  20. Rapidly growing giant cell tumor of bone in a skeletally immature girl.

    PubMed

    Akaike, Gensuke; Ueno, Teruko; Matsumoto, Seiichi; Motoi, Noriko; Matsueda, Kiyoshi

    2016-04-01

    Giant cell tumor of bone (GCTB) in skeletally immature patients is rare, and little is known regarding how fast GCTB can grow. We report a case of a 10-year-old skeletally immature girl with pathologically proven GCTB with obvious growth plate invasion that showed surprisingly rapid growth over only 14 days. A radiograph of the left knee revealed well-circumscribed, geographic bone destruction at the distal metaphysis of the femur with a focal cortical defect, suggesting a pathologic fracture. No abnormal mineralization or periosteal reaction was seen. A CT without contrast and an MRI demonstrated a homogeneous lesion with cortical disruption posteriorly and laterally with a slight soft tissue extension. Biopsy showed numerous multinucleated giant cells and spindle-shaped mononuclear cells without any sign of malignancy, suggesting GCTB. However, rapid lesion enlargement and destruction of the surrounding cortex were noted 14 days after biopsy. Considering the amount of bone destruction, traditional treatment of curettage and bone cement would not suffice to sustain structural strength. In addition, considering the patient's age, the tumor location, and the aggressive course, a malignant tumor, especially a giant cell-rich osteosarcoma, could not be excluded. Therefore, en bloc resection, including the growth plate and prosthetic replacement, were performed. Confirmation of GCTB was made from a pathologic evaluation, and a breach to the growth plate was identified. Since very little inflammatory reaction, degenerative change, or aneurysmal, bone, cyst-like change was found, the growth plate invasion was confirmed as due to GCTB extension, not due to the preoperative biopsy.

  1. Comparison of two in-house real-time PCR assays with MTB Q-PCR Alert and GenoType MTBDRplus for the rapid detection of mycobacteria in clinical specimens.

    PubMed

    Seagar, Amie-Louise; Neish, Barry; Laurenson, Ian F

    2012-10-01

    An in-house IS6110 real-time PCR (IH IS6110), MTB Q-PCR Alert (Q-PCR) and GenoType MTBDRplus (MTBDR; Hain Lifescience) were compared for the direct detection of Mycobacterium tuberculosis complex (MTBC) in 87 specimens following automated NucliSENS easyMAG DNA extraction. This included 82 first smear-positive specimens and three smear-negative specimens. Another in-house real-time PCR with a Mycobacterium genus-specific probe for the internal transcribed spacer (ITS) region (IH ITS) was used to allow a full comparison with culture results. The sensitivities of IH IS6110, Q-PCR, MTBDR and IH ITS for MTBC detection were 100, 92, 87 and 87 %, respectively, compared with culture. Both IS6110-based real-time PCRs (in-house and Q-PCR) were similar in performance, with 91.2 % concordant results for MTBC detection. Inhibition rates were low, with zero to three specimens producing uninterpretable results. However, the Q-PCR failed to detect MTBC in five samples that were smear negative or had few acid-fast bacilli (one to 10 bacilli in 10 microscopic fields) detected by IH IS6110. IH ITS was the least sensitive assay but may be useful when used in conjunction with IS6110 PCR results to determine the presence of non-tuberculous mycobacteria in smear-negative specimens. None of the real-time PCR assays tested provided drug-resistance data. It was concluded that an IH IS6110 assay could easily be incorporated into the workflow of a diagnostic laboratory for rapid and accurate identification of MTBC from clinical specimens. The inclusion of an internal control and amplification of an ITS target enhance the diagnostic utility of the test.

  2. Mycobacteriophage cell binding proteins for the capture of mycobacteria

    PubMed Central

    Arutyunov, Denis; Singh, Upasana; El-Hawiet, Amr; Seckler, Henrique dos Santos; Nikjah, Sanaz; Joe, Maju; Bai, Yu; Lowary, Todd L; Klassen, John S; Evoy, Stephane; Szymanski, Christine M

    2014-01-01

    Slow growing Mycobacterium avium subsp. paratuberculosis (MAP) causes a deadly condition in cattle known as Johne's disease where asymptomatic carriers are the major source of disease transmission. MAP was also shown to be associated with chronic Crohn's disease in humans. Mycobacterium smegmatis is a model mycobacterium that can cause opportunistic infections in a number of human tissues and, rarely, a respiratory disease. Currently, there are no rapid, culture-independent, reliable and inexpensive tests for the diagnostics of MAP or M. smegmatis infections. Bacteriophages are viruses producing a number of proteins that effectively and specifically recognize the cell envelopes of their bacterial hosts. We demonstrate that the mycobacterial phage L5 minor tail protein Gp6 and lysin Gp10 are useful tools for the rapid capture of mycobacteria. Immobilized Gp10 was able to bind both MAP and M. smegmatis cells whereas Gp6 was M. smegmatis specific. Neither of the 2 proteins was able to capture E. coli, salmonella, campylobacter or Mycobacterium marinum cells. Gp6 was detected previously as a component of the phage particle and shows no homology to proteins with known function. Therefore, electrospray ionization mass spectrometry was used to determine whether recombinant Gp6 could bind to a number of chemically synthesized fragments of mycobacterial surface glycans. These findings demonstrate that mycobacteriophage proteins could be used as a pathogen capturing platform that can potentially improve the effectiveness of existing diagnostic methods. PMID:26713219

  3. Prevalence of Non-Tuberculous Mycobacteria in Hospital Waters of Major Cities of Khuzestan Province, Iran.

    PubMed

    Khosravi, Azar Dokht; Hashemi Shahraki, Abdolrazagh; Hashemzadeh, Mohammad; Sheini Mehrabzadeh, Rasa; Teimoori, Ali

    2016-01-01

    Non-tuberculous mycobacteria (NTM) are among the emerging pathogens in immunocompromised individuals including hospitalized patients. So, it is important to consider hospitals water supplies as a source for infection. The aim of this study was to determine the prevalence of NTM in the hospital aquatic systems of Khuzestan, South west of Iran. In total, 258 hospital water samples were collected and examined. After initial sample processing, sediment of each sample were inoculated into two Lowenstein-Jensen medium. The positive cultures were studied with phenotypic tests including growth rate, colony morphology, and pigmentation, with subsequent PCR- restriction enzyme analysis (PRA) and rpoB gene sequence analysis. Mycobacterial strains were isolated from 77 samples (29.8%), comprising 52 (70.1%) rapid growing, and 25 (32.4%) slow growing mycobacteria. Based on the overall results, M. fortuitum (44.1%) was the most common mycobacterial species in hospital water samples, followed by M. gordonae (n = 13, 16.8%) and M. senegalense (n = 5, 7.7%). In conclusion, current study demonstrated the NTM strains as one of the major parts of hospital water supplies with probable potential source for nosocomial infections. This finding also help to shed light on to the dynamics of the distribution and diversity of NTM in the water system of hospitals in the region of study. PMID:27148491

  4. Prevalence of Non-Tuberculous Mycobacteria in Hospital Waters of Major Cities of Khuzestan Province, Iran

    PubMed Central

    Khosravi, Azar Dokht; Hashemi Shahraki, Abdolrazagh; Hashemzadeh, Mohammad; Sheini Mehrabzadeh, Rasa; Teimoori, Ali

    2016-01-01

    Non-tuberculous mycobacteria (NTM) are among the emerging pathogens in immunocompromised individuals including hospitalized patients. So, it is important to consider hospitals water supplies as a source for infection. The aim of this study was to determine the prevalence of NTM in the hospital aquatic systems of Khuzestan, South west of Iran. In total, 258 hospital water samples were collected and examined. After initial sample processing, sediment of each sample were inoculated into two Lowenstein-Jensen medium. The positive cultures were studied with phenotypic tests including growth rate, colony morphology, and pigmentation, with subsequent PCR- restriction enzyme analysis (PRA) and rpoB gene sequence analysis. Mycobacterial strains were isolated from 77 samples (29.8%), comprising 52 (70.1%) rapid growing, and 25 (32.4%) slow growing mycobacteria. Based on the overall results, M. fortuitum (44.1%) was the most common mycobacterial species in hospital water samples, followed by M. gordonae (n = 13, 16.8%) and M. senegalense (n = 5, 7.7%). In conclusion, current study demonstrated the NTM strains as one of the major parts of hospital water supplies with probable potential source for nosocomial infections. This finding also help to shed light on to the dynamics of the distribution and diversity of NTM in the water system of hospitals in the region of study. PMID:27148491

  5. An Automated System for Rapid Non-Destructive Enumeration of Growing Microbes

    PubMed Central

    London, Roanna; Schwedock, Julie; Sage, Andrew; Valley, Heather; Meadows, Jamie; Waddington, Michael; Straus, Don

    2010-01-01

    Background The power and simplicity of visual colony counting have made it the mainstay of microbiological analysis for more than 130 years. A disadvantage of the method is the long time required to generate visible colonies from cells in a sample. New rapid testing technologies generally have failed to maintain one or more of the major advantages of culture-based methods. Principal Findings We present a new technology and platform that uses digital imaging of cellular autofluorescence to detect and enumerate growing microcolonies many generations before they become visible to the eye. The data presented demonstrate that the method preserves the viability of the microcolonies it detects, thus enabling generation of pure cultures for microbial identification. While visual colony counting detects Escherichia coli colonies containing about 5×106 cells, the new imaging method detects E. coli microcolonies when they contain about 120 cells and microcolonies of the yeast Candida albicans when they contain only about 12 cells. We demonstrate that digital imaging of microcolony autofluorescence detects a broad spectrum of prokaryotic and eukaryotic microbes and present a model for predicting the time to detection for individual strains. Results from the analysis of environmental samples from pharmaceutical manufacturing plants containing a mixture of unidentified microbes demonstrate the method's improved test turnaround times. Conclusion This work demonstrates a new technology and automated platform that substantially shortens test times while maintaining key advantages of the current methods. PMID:20062794

  6. The detection of roadside pollution of rapidly growing city in arid region using the magnetic proxies

    NASA Astrophysics Data System (ADS)

    El-Hasan, Tayel

    2008-03-01

    This work is a complementary investigation to the earlier urban soil survey for a rapidly growing city of relatively high traffic density. Therefore, it aims to apply the environmental magnetism approach to assess the roadside pollution at a known polluted site. The used magnetic proxies are the initial magnetic susceptibility and saturation magnetization. The results prove the applicability of this method in detecting roadside pollution. The shape and magnitude of the magnetic signals was affected by the topography and prevailing wind direction that caused the magnetic peaks to be shifted accordingly. Particle size was found to affect the magnetic material content, where sand size (63-150 μm) bears the highest magnetic signals relative to smaller silt size (<63 μm). The magnetic anomalies coincided positively with heavy metal pollution in the studied site, which might indicate that the magnetic materials serve as an effective proxy for the metallic pollution (i.e., Fe, Ni, Pb, Cu, and Zn) originated mainly from vehicular sources.

  7. Evaluation of a mass measles immunisation campaign in a rapidly growing peri-urban area.

    PubMed

    Kearney, M; Yach, D; Van Dyk, H; Fisher, S A

    1989-08-19

    A mass measles immunisation campaign, with a target coverage rate of 85-90%, was launched in Khayelitsha, a rapidly growing urban township in the Cape Town area. Cross-sectional surveys of the measles immunisation status of resident 6-23-month-old infants were conducted immediately before, immediately after, and approximately 2 months after the campaign in order to determine the effectiveness of a mass campaign in boosting coverage in an area with a high influx rate. Immunisation coverage rates were 55% in the first survey, 76% in the second, and 72% in the third. In the first survey, coverage rates for children born in Cape Town were 1.4 times higher than those born elsewhere. This trend continued throughout the survey. Duration of stay in Cape Town also influenced coverage, with rates for the recently arrived children being considerably lower than those for the more established Cape Town residents. The influx rate between the second and third survey (over the Christmas period) was 9.1% per month. Failure to reach the targeted rate is attributed to the influx rate, campaign design and implementation, and factors related to child and career mobility. Alternative immunisation strategies, with social awareness playing a key role, are being urgently investigated.

  8. Evaluation of two line probe assays for rapid detection of Mycobacterium tuberculosis, tuberculosis (TB) drug resistance, and non-TB Mycobacteria in HIV-infected individuals with suspected TB.

    PubMed

    Luetkemeyer, Anne F; Kendall, Michelle A; Wu, Xingye; Lourenço, Maria Cristina; Jentsch, Ute; Swindells, Susan; Qasba, Sarojini S; Sanchez, Jorge; Havlir, Diane V; Grinsztejn, Beatriz; Sanne, Ian M; Firnhaber, Cynthia

    2014-04-01

    Limited performance data from line probe assays (LPAs), nucleic acid tests used for the rapid diagnosis of tuberculosis (TB), nontuberculosis mycobacteria (NTM), and Mycobacterium tuberculosis drug resistance are available for HIV-infected individuals, in whom paucibacillary TB is common. In this study, the strategy of testing sputum with GenoType MTBDRplus (MTBDR-Plus) and GenoType Direct LPA (Direct LPA) was compared to a gold standard of one mycobacterial growth indicator tube (MGIT) liquid culture. HIV-positive (HIV(+)) individuals with suspected TB from southern Africa and South America with <7 days of TB treatment had 1 sputum specimen tested with Direct LPA, MTBDR-Plus LPA, smear microscopy, MGIT, biochemical identification of mycobacterial species, and culture-based drug-susceptibility testing (DST). Of 639 participants, 59.3% were MGIT M. tuberculosis culture positive, of which 276 (72.8%) were acid-fast bacillus (AFB) smear positive. MTBDR-Plus had a sensitivity of 81.0% and a specificity of 100%, with sensitivities of 44.1% in AFB smear-negative versus 94.6% in AFB smear-positive specimens. For specimens that were positive for M. tuberculosis by MTBDR-Plus, the sensitivity and specificity for rifampin resistance were 91.7% and 96.6%, respectively, and for isoniazid (INH) they were 70.6% and 99.1%. The Direct LPA had a sensitivity of 88.4% and a specificity of 94.6% for M. tuberculosis detection, with a sensitivity of 72.5% in smear-negative specimens. Ten of 639 MGIT cultures grew Mycobacterium avium complex or Mycobacterium kansasii, half of which were detected by Direct LPA. Both LPA assays performed well in specimens from HIV-infected individuals, including in AFB smear-negative specimens, with 72.5% sensitivity for M. tuberculosis identification with the Direct LPA and 44.1% sensitivity with MTBDR-Plus. LPAs have a continued role for use in settings where rapid identification of INH resistance and clinically relevant NTM are priorities.

  9. Survey of solid waste generation and composition in a rapidly growing urban area in Central Nigeria.

    PubMed

    Sha'Ato, R; Aboho, S Y; Oketunde, F O; Eneji, I S; Unazi, G; Agwa, S

    2007-01-01

    The objective of this study was to carry out a field survey of the solid waste generation profile in parts of Makurdi, a rapidly growing urban city in north central Nigeria. The areas surveyed covered low, medium and high-density residential quarters, representing high/medium/low income groups in the area. Results of the survey show that the bulk ( approximately 82%) of the solid waste generated in the area originates from households, rather than from commercial, institutional or industrial premises. Of the waste from households, a substantial proportion consists of various putrescible materials (36-57%), with ash, dust and sand (combined) forming another significant proportion (21-41%). From the non-household sources, putrescible matter is also significant (23-45%), as is the combined ash/dust/sand fraction (32-36%). The quantity of plastics/cellophane materials from household and non-household sources was, however, comparable (6-10%). There was more paper from commercial and institutional premises (9-12%) than from household or small/medium scale industrial premises (2-4%). Glass (0.1-6.9%), metals (mostly cans and bottle corks, 0.7-3.4%) and textiles (0.3-6%) form only a minor proportion of the waste across generators. Waste generation rates were for households, 0.54kg/cap/day; for commercial, 0.018kg/m(2)/day; institutional, 0.015kg/m(2)/day while for small and medium scale industries, the rate was 0.47kg/m(2)/day. As there is no previous study of this kind in the Makurdi urban area, what is reported here may be taken as baseline for the entire area. The implications of the findings for solid waste management planning are discussed.

  10. Physiology of Mycobacteria

    PubMed Central

    Cook, Gregory M.; Berney, Michael; Gebhard, Susanne; Heinemann, Matthias; Cox, Robert A.; Danilchanka, Olga; Niederweis, Michael

    2013-01-01

    mycobacteria of course stems from the diseases they cause and, lest it be imagined that tuberculosis is a disease which has now been largely conquered and that leprosy is of relatively rare occurrence, current estimates for the number of case of tuberculosis and leprosy in the world today are 20,000,000 and 11,000,000, respectively (Bechelli and Dominguez, 1972). The annual estimated mortality rate is equally dramatic, namely 3,000,000 (World Health Organization, 1974). Also causing unease is the continuing isolation from tubercular patients of strains already resistant to one or more chemotherapeutic agent”. C. Ratledge (1976). PMID:19573696

  11. [Evaluation of blood agar medium for the growth of mycobacteria].

    PubMed

    Coban, Ahmet Yılmaz; Akgüneş, Alper; Durupınar, Belma

    2011-10-01

    This study was aimed to evaluate the performance of blood agar for the growth of mycobacteria from clinical specimens sent to Mycobacteriology Laboratory of Samsun Chest Diseases Hospital. One hundred fifty six clinical specimens including 123 sputum, 28 bronchoalveolar lavage (BAL) and 5 pleural fluid specimens were inoculated in Löwenstein-Jensen (LJ), BACTEC MGIT 960 system (Becton Dickinson, USA) and blood agar following decontamination process. The specimens were also simultaneously examined for the presence of acid-fast bacilli (AFB). Thirty five mycobacteria strains (33 Mycobacterium tuberculosis and 2 atypical mycobacteria) grew in blood agar, 38 (36 M.tuberculosis and 2 atypical mycobacteria) in LJ media and 46 (44 M.tuberculosis and 2 atypical mycobacteria) in BACTEC MGIT 960 system. Among 29 AFB negative specimens, 20 revealed growth in both blood agar and LJ medium and 27 in MGIT system. AFB positive 20 samples yielded growth in 15 samples in blood agar, 18 in LJ medium and 19 in MGIT system. Among the total of 156 samples, contamination was observed in 15 (9.6%) samples in blood agar, 16 (10.2%) in LJ medium and 18 (11.5%) in MGIT system. Growth time was 5-35 days (mean 18 ± 7.4), 11-35 days (mean 19 ± 5.9) and 5-15 days (mean 10 ± 2.4) for blood agar, LJ medium and BACTEC MGIT 960 system, respectively. The three samples which revealed contamination in BACTEC MGIT 960 system, grew successfully in both blood agar and LJ medium without contamination. In one sample, growth was observed only in LJ medium but neither in blood agar nor BACTEC MGIT 960 system. However, in another sample, growth was observed only in blood agar while no growth was detected in LJ or BACTEC MGIT 960 system. Six samples yielded mycobacteria only in BACTEC MGIT 960 system. These results indicated that simultaneous use of one liquid and one solid medium to grow mycobacteria from the clinical samples seemed to be complementary. Blood agar was a promising choice since it was found

  12. Management of a rapidly growing peritoneal dialysis population at the First Affiliated Hospital of Sun Yat-sen University.

    PubMed

    Yu, Xueqing; Yang, Xiao; Huang, Naya

    2014-06-01

    Managing a rapidly growing peritoneal dialysis program with more than 1000 patients involves multiple challenges, labor constraints, logistics, and excessive geographic distance. This paper describes how Sun Yat-sen University, Guangzhou, China, manages those issues, while simultaneously improving quality of the care and, subsequently, clinical outcomes.

  13. Rapidly Growing Brtl/+ Mouse Model of Osteogenesis Imperfecta Improves Bone Mass and Strength with Sclerostin Antibody Treatment

    PubMed Central

    Sinder, Benjamin P.; Salemi, Joseph D.; Ominsky, Michael S.; Caird, Michelle S.; Marini, Joan C.; Kozloff, Kenneth M.

    2014-01-01

    Osteogenesis imperfecta (OI) is a heritable collagen-related bone dysplasia, characterized by brittle bones with increased fracture risk that presents most severely in children. Anti-resorptive bisphosphonates are frequently used to treat pediatric OI and controlled clinical trials have shown bisphosphonate therapy improves vertebral outcomes but has little benefit on long bone fracture rate. New treatments which increase bone mass throughout the pediatric OI skeleton would be beneficial. Sclerostin antibody (Scl-Ab) is a potential candidate anabolic therapy for pediatric OI and functions by stimulating osteoblastic bone formation via the canonical wnt signaling pathway. To explore the effect of Scl-Ab on the rapidly growing OI skeleton, we treated rapidly growing 3 week old Brtl/+ mice, harboring a typical heterozygous OI-causing Gly->Cys substitution on col1a1, for 5 weeks with Scl-Ab. Scl-Ab had anabolic effects in Brtl/+ and led to new cortical bone formation and increased cortical bone mass. This anabolic action resulted in improved mechanical strength to WT Veh levels without altering the underlying brittle nature of the material. While Scl-Ab was anabolic in trabecular bone of the distal femur in both genotypes, the effect was less strong in these rapidly growing Brtl/+ mice compared to WT. In conclusion, Scl-Ab was able to stimulate bone formation in a rapidly growing Brtl/+ murine model of OI, and represents a potential new therapy to improve bone mass and reduce fracture risk in pediatric OI. PMID:25445450

  14. Malachite green interferes with postantibiotic recovery of mycobacteria.

    PubMed

    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.

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

    PubMed

    Hoefsloot, Wouter; van Ingen, Jakko; Andrejak, Claire; Angeby, Kristian; Bauriaud, Rosine; Bemer, Pascale; Beylis, Natalie; Boeree, Martin J; Cacho, Juana; Chihota, Violet; Chimara, Erica; Churchyard, Gavin; Cias, Raquel; Daza, Rosa; Daley, Charles L; Dekhuijzen, P N Richard; Domingo, Diego; Drobniewski, Francis; Esteban, Jaime; Fauville-Dufaux, Maryse; Folkvardsen, Dorte Bek; Gibbons, Noel; Gómez-Mampaso, Enrique; Gonzalez, Rosa; Hoffmann, Harald; Hsueh, Po-Ren; Indra, Alexander; Jagielski, Tomasz; Jamieson, Frances; Jankovic, Mateja; Jong, Eefje; Keane, Joseph; Koh, Wo-Jung; Lange, Berit; Leao, Sylvia; Macedo, Rita; Mannsåker, Turid; Marras, Theodore K; Maugein, Jeannette; Milburn, Heather J; Mlinkó, Tamas; Morcillo, Nora; Morimoto, Kozo; Papaventsis, Dimitrios; Palenque, Elia; Paez-Peña, Mar; Piersimoni, Claudio; Polanová, Monika; Rastogi, Nalin; Richter, Elvira; Ruiz-Serrano, Maria Jesus; Silva, Anabela; da Silva, M Pedro; Simsek, Hulya; van Soolingen, Dick; Szabó, Nora; Thomson, Rachel; Tórtola Fernandez, Teresa; Tortoli, Enrico; Totten, Sarah E; Tyrrell, Greg; Vasankari, Tuula; Villar, Miguel; Walkiewicz, Renata; Winthrop, Kevin L; Wagner, Dirk

    2013-12-01

    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 Tuberculosis Network European Trials Group (TB-NET), provided identification results of the total number of patients in 2008 in whom NTM were isolated from pulmonary samples. From these data, we visualised the relative distribution of the different NTM found per continent and per country. We received species identification data for 20 182 patients, from 62 laboratories in 30 countries across six continents. 91 different NTM species were isolated. Mycobacterium avium complex (MAC) bacteria predominated in most countries, followed by M. gordonae and M. xenopi. Important differences in geographical distribution of MAC species as well as M. xenopi, M. kansasii and rapid-growing mycobacteria were observed. This snapshot demonstrates that the species distribution among NTM isolates from pulmonary specimens in the year 2008 differed by continent and differed by country within these continents. These differences in species distribution may partly determine the frequency and manifestations of pulmonary NTM disease in each geographical location.

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

    PubMed

    Hoefsloot, Wouter; van Ingen, Jakko; Andrejak, Claire; Angeby, Kristian; Bauriaud, Rosine; Bemer, Pascale; Beylis, Natalie; Boeree, Martin J; Cacho, Juana; Chihota, Violet; Chimara, Erica; Churchyard, Gavin; Cias, Raquel; Daza, Rosa; Daley, Charles L; Dekhuijzen, P N Richard; Domingo, Diego; Drobniewski, Francis; Esteban, Jaime; Fauville-Dufaux, Maryse; Folkvardsen, Dorte Bek; Gibbons, Noel; Gómez-Mampaso, Enrique; Gonzalez, Rosa; Hoffmann, Harald; Hsueh, Po-Ren; Indra, Alexander; Jagielski, Tomasz; Jamieson, Frances; Jankovic, Mateja; Jong, Eefje; Keane, Joseph; Koh, Wo-Jung; Lange, Berit; Leao, Sylvia; Macedo, Rita; Mannsåker, Turid; Marras, Theodore K; Maugein, Jeannette; Milburn, Heather J; Mlinkó, Tamas; Morcillo, Nora; Morimoto, Kozo; Papaventsis, Dimitrios; Palenque, Elia; Paez-Peña, Mar; Piersimoni, Claudio; Polanová, Monika; Rastogi, Nalin; Richter, Elvira; Ruiz-Serrano, Maria Jesus; Silva, Anabela; da Silva, M Pedro; Simsek, Hulya; van Soolingen, Dick; Szabó, Nora; Thomson, Rachel; Tórtola Fernandez, Teresa; Tortoli, Enrico; Totten, Sarah E; Tyrrell, Greg; Vasankari, Tuula; Villar, Miguel; Walkiewicz, Renata; Winthrop, Kevin L; Wagner, Dirk

    2013-12-01

    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 Tuberculosis Network European Trials Group (TB-NET), provided identification results of the total number of patients in 2008 in whom NTM were isolated from pulmonary samples. From these data, we visualised the relative distribution of the different NTM found per continent and per country. We received species identification data for 20 182 patients, from 62 laboratories in 30 countries across six continents. 91 different NTM species were isolated. Mycobacterium avium complex (MAC) bacteria predominated in most countries, followed by M. gordonae and M. xenopi. Important differences in geographical distribution of MAC species as well as M. xenopi, M. kansasii and rapid-growing mycobacteria were observed. This snapshot demonstrates that the species distribution among NTM isolates from pulmonary specimens in the year 2008 differed by continent and differed by country within these continents. These differences in species distribution may partly determine the frequency and manifestations of pulmonary NTM disease in each geographical location. PMID:23598956

  17. A seven-gene, multilocus, genus-wide approach to the phylogeny of mycobacteria using supertrees.

    PubMed

    Mignard, Sophie; Flandrois, Jean-Pierre

    2008-06-01

    This is the first study that estimates mycobacterial phylogeny using the maximum-likelihood method (PhyML-aLRT) on a seven-gene concatenate (hsp65, rpoB, 16S rRNA, smpB, sodA, tmRNA and tuf) and the super distance matrix (SDM) supertree method. Two sets of sequences were studied: a complete seven gene sequence set (set R, type strains of 87 species) and an incomplete set (set W, 132 species) with some missing data. Congruencies were computed by using the consense program (phylip package). The evolution rate of each gene was determined, as was the evolution rate of each strain for a given gene. Maximum-likelihood trees resulting from concatenation of the R and W sets resulted in a similar phylogeny, usually showing an early separation between slow-growing (SG) and rapidly growing (RG) mycobacteria. The SDM tree for the W set resulted in a different phylogeny. The separation of SG and RG was still evident, but it was located later in the nodes. The SG were therefore positioned as a subgroup of RG. Maximum-likelihood phylogenetic reconstruction was less affected by increasing the number of strains (with incomplete data), but did seem to cushion the variability of the evolution rate (ER), whereas the SDM method seemed to be more accurate and took into account both the differing ER values and the incomplete data. With regard to ER, it was observed that the 16S rRNA gene was the gene that displayed the slowest evolution, whereas smpB was the most rapidly evolving gene. Surprisingly, these two genes alone accurately separated the SG from the RG on the basis of their ER values. This study focused on the differences in ER between genes and in some cases linked the ER to the phenotypic classification of the mycobacteria. PMID:18523191

  18. Phylogenetic comparison of two polycyclic aromatic hydrogen-degrading mycobacteria

    SciTech Connect

    Govindaswami, M.; Loper, J.C.; Feldhake, D.J.

    1995-09-01

    Two mycobacterial strains previously isolated from fossil-fuel-contaminated environments and shown to degrade four- and/or five-ring polycyclic aromatic hydrocarbons were further characterized. The two strains, PYR-I and RJGII-135, had similar growth characteristics, colony morphologies, and scotochromogenic pigmentations. DNA amplification fringerprints obtained with total genomic DNA indicated some strain similarities but with several distinctly different bands. Moreover, phylogenetic analysis based upon essentially full-length 16S rRNA gene sequences separates the two strains as distinct species within the fast-growing group of mycobacteria. Although both strains are thermosensitive, strain PYR-I has the bulged U between positions 184 and 193 characteristic of thermotolerant mycobacteria. Both strains are of potential use for reintroduction into and bioremediation of polycyclic aromatic hydrocarbon-contaminated soils. 26 refs., 4 figs., 1 tab.

  19. Confinement-Induced Drug-Tolerance in Mycobacteria Mediated by an Efflux Mechanism

    PubMed Central

    Luthuli, Brilliant B.; Purdy, Georgiana E.; Balagaddé, Frederick K.

    2015-01-01

    Tuberculosis (TB) is the world’s deadliest curable disease, responsible for an estimated 1.5 million deaths annually. A considerable challenge in controlling this disease is the prolonged multidrug chemotherapy (6 to 9 months) required to overcome drug-tolerant mycobacteria that persist in human tissues, although the same drugs can sterilize genetically identical mycobacteria growing in axenic culture within days. An essential component of TB infection involves intracellular Mycobacterium tuberculosis bacteria that multiply within macrophages and are significantly more tolerant to antibiotics compared to extracellular mycobacteria. To investigate this aspect of human TB, we created a physical cell culture system that mimics confinement of replicating mycobacteria, such as in a macrophage during infection. Using this system, we uncovered an epigenetic drug-tolerance phenotype that appears when mycobacteria are cultured in space-confined bioreactors and disappears in larger volume growth contexts. Efflux mechanisms that are induced in space-confined growth environments contribute to this drug-tolerance phenotype. Therefore, macrophage-induced drug tolerance by mycobacteria may be an effect of confined growth among other macrophage-specific mechanisms. PMID:26295942

  20. Confinement-Induced Drug-Tolerance in Mycobacteria Mediated by an Efflux Mechanism.

    PubMed

    Luthuli, Brilliant B; Purdy, Georgiana E; Balagaddé, Frederick K

    2015-01-01

    Tuberculosis (TB) is the world's deadliest curable disease, responsible for an estimated 1.5 million deaths annually. A considerable challenge in controlling this disease is the prolonged multidrug chemotherapy (6 to 9 months) required to overcome drug-tolerant mycobacteria that persist in human tissues, although the same drugs can sterilize genetically identical mycobacteria growing in axenic culture within days. An essential component of TB infection involves intracellular Mycobacterium tuberculosis bacteria that multiply within macrophages and are significantly more tolerant to antibiotics compared to extracellular mycobacteria. To investigate this aspect of human TB, we created a physical cell culture system that mimics confinement of replicating mycobacteria, such as in a macrophage during infection. Using this system, we uncovered an epigenetic drug-tolerance phenotype that appears when mycobacteria are cultured in space-confined bioreactors and disappears in larger volume growth contexts. Efflux mechanisms that are induced in space-confined growth environments contribute to this drug-tolerance phenotype. Therefore, macrophage-induced drug tolerance by mycobacteria may be an effect of confined growth among other macrophage-specific mechanisms. PMID:26295942

  1. Mycobacteria in nail salon whirlpool footbaths, California.

    PubMed

    Vugia, Duc J; Jang, Yvonne; Zizek, Candi; Ely, Janet; Winthrop, Kevin L; Desmond, Edward

    2005-04-01

    In 2000, an outbreak of Mycobacterium fortuitum furunculosis affected customers using whirlpool footbaths at a nail salon. We swabbed 30 footbaths in 18 nail salons from 5 California counties and found mycobacteria in 29 (97%); M. fortuitum was the most common. Mycobacteria may pose an infectious risk for pedicure customers.

  2. Mycobacteria in Nail Salon Whirlpool Footbaths, California

    PubMed Central

    Jang, Yvonne; Zizek, Candi; Ely, Janet; Winthrop, Kevin L.; Desmond, Edward

    2005-01-01

    In 2000, an outbreak of Mycobacterium fortuitum furunculosis affected customers using whirlpool footbaths at a nail salon. We swabbed 30 footbaths in 18 nail salons from 5 California counties and found mycobacteria in 29 (97%); M. fortuitum was the most common. Mycobacteria may pose an infectious risk for pedicure customers. PMID:15829204

  3. Earthworms (Oligochaeta, Lumbricidae) and mycobacteria.

    PubMed

    Fischer, O A; Matlova, L; Bartl, J; Dvorska, L; Svastova, P; du Maine, R; Melicharek, I; Bartos, M; Pavlik, I

    2003-02-25

    The objective of the study was to define the role of earthworms in the survival of mycobacteria in animal populations. In 13 sampling sites mycobacteria were detected in 53 (5.5%) samples of faeces and parenchymatous tissues from animals, in 25 (7.3%) environmental and in nine (8.2%) earthworm samples. In cattle and goat farms affected by Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) of IS900 restriction fragment length polymorphism (RFLP) type B-C1 was isolated from 37 (4.6%) faecal samples, three (1.4%) environmental and one (3.1%) earthworm sample. Investigations of aviaries affected by avian tuberculosis detected M. avium of genotype IS901+ and IS1245+ in six (7.9%) bird's faecal and in four (4.4%) environmental samples. M. avium (genotype IS901- and IS1245+) was detected in four (4.4%) and M. abscessus in one (1.1%) environmental sample. M. avium of genotype IS901- and IS1245+ and M. gastri were isolated from three (6.4%) earthworm samples. In pig farm with mycobacteriosis M. avium of genotype IS901- and IS1245+ was detected in five (20.0%) faecal samples from pigs and in four (12.9%) environmental samples. M. scrofulaceum was isolated in one (4.6%) sample of Lumbricus rubellus. In laboratory experiments identical RFLP types of M. paratuberculosis were isolated from bodies and faeces of earthworms 1-2 days after the last contact with the faeces contaminated with the same RFLP type of M. paratuberculosis. The results suggest that earthworms may become vectors of mycobacteria. PMID:12477646

  4. Mycobacterial virulence. Virulent strains of Mycobacteria tuberculosis have faster in vivo doubling times and are better equipped to resist growth-inhibiting functions of macrophages in the presence and absence of specific immunity.

    PubMed

    North, R J; Izzo, A A

    1993-06-01

    The kinetics of growth of two virulent strains of mycobacteria (M. tuberculosis Erdman and M. tuberculosis H37Rv) and two attenuated strains (M. tuberculosis H37Ra and M. bovis Bacillus Calmette-Guerin [BCG]) were studied in the lungs, livers, spleens, and kidneys of severe combined immunodeficient (SCID) mice and of their coisogenic CB-17 immunocompetent counterparts. It was found, in keeping with the findings of earlier investigators (Pierce, C. H., R. J. Dubos, and W. B. Schaefer. 1953. J. Exp. Med. 97:189.), that in immunocompetent mice, virulent organisms grew progressively only in the lungs, whereas the growth of attenuated organisms was controlled in all organs. In SCID mice, in contrast, virulent mycobacteria grew rapidly and progressively in all organs, as did BCG, although at a slower rate. However, H37Ra failed to grow progressively in any organs of SCID mice, unless the mice were treated with hydrocortisone. In fact, hydrocortisone treatment enabled virulent, as well as attenuated, organisms to grow strikingly more rapidly in all organs of SCID mice and in all organs of CB-17 mice. A histological study showed that in SCID mice, multiplication of mycobacteria in the liver occurs in the cytoplasm of macrophages in granulomas and presumably in macrophages in other organs. It is suggested, therefore, that the macrophages of SCID mice possess a glucocorticoid-sensitive mycobacterial mechanism that prevents virulent and avirulent mycobacteria from expressing their true minimal doubling times. In the absence of this mechanism in the lungs of hydrocortisone-treated SCID mice, the doubling times of Erdman, H37Rv, BCG, and H37Ra were 17.7, 17.4, 44.6, and 98.6 h, respectively. The possible importance of a rapid multiplication rate for mycobacterial virulence is discussed. PMID:8496688

  5. Strategies used by pathogenic and nonpathogenic mycobacteria to synthesize rRNA.

    PubMed Central

    Gonzalez-y-Merchand, J A; Garcia, M J; Gonzalez-Rico, S; Colston, M J; Cox, R A

    1997-01-01

    One rRNA operon of all mycobacteria studied so far is located downstream from a gene thought to code for the enzyme UDP-N-acetylglucosamine carboxyvinyl transferase (UNAcGCT), which is important to cell wall synthesis. This operon has been designated rrnAf for fast-growing mycobacteria and rrnAs for slow growers. We have investigated the upstream sequences and promoter activities of rrnA operons of typical fast growers which also possess a second rrn (rrnBf) operon and of the rrnA operons of the fast growers Mycobacterium abscessus and Mycobacterium chelonae, which each have a single rrn operon per genome. These fast growers have a common strategy for increasing the efficiency of transcription of their rrnA operons, thereby increasing the cells' potential for ribosome synthesis. This strategy involves the use of multiple (three to five) promoters which may have arisen through successive duplication events. Thus we have identified a hypervariable multiple promoter region (HMPR) located between the UNAcGCT gene and the 16S rRNA coding region. Two promoters, P1 and PCL1, appear to play pivotal roles in mycobacterial rRNA synthesis; they are present in all of the species examined and are the only promoters used for rRNA synthesis by the pathogenic slow growers. P1 is located within the coding region of the UNAcGCT gene, and PCL1 has a characteristic sequence that is related to but distinct from that of the additional promoters. In fast-growing species, P1 and PCL1 produce less than 10% of rRNA transcripts, so the additional promoters found in the HMPR are important in increasing the potential for rRNA synthesis during rapid growth. In contrast, rrnB operons appear to be regulated by a single promoter; because less divergence has taken place, rrnB appears to be younger than rrnA. PMID:9371439

  6. Rapid growing clay coatings to reduce the fire threat of furniture.

    PubMed

    Kim, Yeon Seok; Li, Yu-Chin; Pitts, William M; Werrel, Martin; Davis, Rick D

    2014-02-12

    Layer-by-layer (LbL) assembly coatings reduce the flammability of textiles and polyurethane foam but require extensive repetitive processing steps to produce the desired coating thickness and nanoparticle fire retardant content that translates into a fire retardant coating. Reported here is a new hybrid bi-layer (BL) approach to fabricate fire retardant coatings on polyurethane foam. Utilizing hydrogen bonding and electrostatic attraction along with the pH adjustment, a fast growing coating with significant fire retardant clay content was achieved. This hybrid BL coating exhibits significant fire performance improvement in both bench scale and real scale tests. Cone calorimetry bench scale tests show a 42% and 71% reduction in peak and average heat release rates, respectively. Real scale furniture mockups constructed using the hybrid LbL coating reduced the peak and average heat release rates by 53% and 63%, respectively. This is the first time that the fire safety in a real scale test has been reported for any LbL technology. This hybrid LbL coating is the fastest approach to develop an effective fire retardant coating for polyurethane foam.

  7. Soft Tissue Infection Caused by Rapid Growing Mycobacterium following Medical Procedures: Two Case Reports and Literature Review

    PubMed Central

    Lin, Shih-Sen; Lee, Chin-Cheng

    2014-01-01

    Non-tubecrulosis mycobacterium infections were increasingly reported either pulmonary or extrapulmonary in the past decades. In Taiwan, we noticed several reports about the soft tissue infections caused by rapid growing mycobacterium such as Mycobacterium abscessus, Mycobacterium chelonae, on newspaper, magazines, or the multimedia. Most of them occurred after a plastic surgery, and medical or non-medical procedures. Here, we reported two cases of these infections following medical procedures. We also discussed common features and the clinical course of the disease, the characteristics of the infected site, and the treatment strategy. The literatures were also reviewed, and the necessity of the treatment guidelines was discussed. PMID:24882980

  8. Dietary restriction does not adversely affect bone geometry and mechanics in rapidly growing male wistar rats.

    PubMed

    Lambert, Jennifer; Lamothe, Jeremy M; Zernicke, Ronald F; Auer, Roland N; Reimer, Raylene A

    2005-02-01

    The present study assessed the effects of dietary restriction on tibial and vertebral mechanical and geometrical properties in 2-mo-old male Wistar rats. Two-month-old male Wistar rats were randomized to the ad libitum (n=8) or the 35% diet-restricted (DR) feeding group (n=9) for 5 mo. Tibiae and L6 vertebrae were dissected out for microcomputed tomography (microCT) scanning and subsequently fractured in biomechanical testing to determine geometrical and mechanical properties. The DR group had significantly lower mean tibial length, mass, area, and cross-sectional moment of inertia, as well as vertebral energy to maximal load. After adjustment for body mass, however, DR tibial mean maximal load and stiffness, and DR vertebral area, height, volume, and maximal load were significantly greater, relative to ad libitum means. No significant differences were found between the DR and ad libitum mineral ash fractions. Because the material properties of the tibiae between the two groups were not significantly different, presumably the material integrity of the bones was not adversely affected as a consequence of DR. The similar material characteristics were consistent with mineral ash fractions that were not different between the two groups. Vertebral maximal load and stiffness were not significant between the DR and ad libitum animals. Importantly, we show that a level of dietary restriction (35%) that is less severe than many studies (40%), and without micronutrient compensation does not adversely affect tibial and vertebral mechanical properties in young growing male rats when normalized for body mass. PMID:15585686

  9. 'Emerging' mycobacteria in South Africa.

    PubMed

    van Helden, P D; Parsons, S D C; Gey van Pittius, N C

    2009-12-01

    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. PMID:20458859

  10. Method and apparatus for rapidly growing films on substrates using pulsed supersonic jets

    DOEpatents

    Eres, Diula; Lowndes, Douglas H.

    1992-01-01

    A method and apparatus for the rapid and economical deposition of uniform and high quality films upon a substrate for subsequent use in producing electronic devices, for example. The resultant films are either epitaxial (crystalline) or amorphous depending upon the incidence rate and the temperature and structure of the substrate. The deposition is carried out in a chamber maintained at about 10.sup.-6 Torr. A gaseous source of the material for forming the deposit is injected into the deposition chamber in the form of a pulsed supersonic jet so as to obtain a high incidence rate. The supersonic jet is produced by a pulsed valve between a relatively high presure reservoir, containing the source gaseous molecules, and the deposition chamber; the valve has a small nozzle orifice (e.g., 0.1-1.0 mm diameter). The type of deposit (crystalline amorphous) is then dependent upon the temperature and structure of the substrate. Very high deposition rates are achieved, and the deposit is very smooth and of uniform thickness. Typically the deposition rate is about 100 times that of much more expensive conventional molecular beam methods for deposition, and comparable to certain expensive plasma-assisted CVD methods of the art. The high growth rate of this method results in a reduced contamination of the deposit from other elements in the environment. The method is illustrated by the deposition of epitaxial and amorphour germanium films upon GaAs substrates.

  11. A rapidly growing moraine-dammed glacial lake on Ngozumpa Glacier, Nepal

    NASA Astrophysics Data System (ADS)

    Thompson, Sarah S.; Benn, Douglas I.; Dennis, Kathryn; Luckman, Adrian

    2012-04-01

    Moraine-dammed glacial lakes are becoming increasingly common in the Himalaya as a result of glacier mass loss, causing concern about glacier lake outburst flood risk. In addition to extant lakes, the potential exists for many more to form, as more glaciers ablate down to the level of potential moraine dams. In this paper, we document the recent rapid growth of, a moraine-dammed lake on Ngozumpa Glacier, Nepal. Using a combination of ground-based mapping and sonar surveys, aerial photographs (< 1 m resolution), and ASTER imagery (15 m resolution), processes and rates of lake expansion have been determined. The lake first formed between 1984 and 1992 when collapse of an englacial conduit allowed water to accumulate at the level of a gap in the lateral moraine, ~km from the glacier terminus. Lake growth was initially slow, but since 2001 it has undergone exponential growth at an average rate of 10% y-1. In 2009, the lake area was 300,000 m2, and its volume was at least 2.2 million m3. Calving, subaqueous melting, and melting of subaerial ice faces all contribute to the expansion of the lake; but large-scale, full-height slab calving is now the dominant contributor to growth. Comparison with other lakes in the region indicate that lake growth will likely continue unchecked whilst the spillway remains at its current level and may attain a volume of hundreds of millions of cubic metres within the next few decades.

  12. Protective effect of breastfeeding on diarrhea among children in a rapidly growing newly developed society.

    PubMed

    Ehlayel, Mohammad S; Bener, Abdulbari; Abdulrahman, Hatim M

    2009-01-01

    of infantile diarrhea. This observation is particularly important given the growing concern that, as an unwanted effect of 'modernization', breastfeeding is on the decline in Qatar and comparable populations elsewhere.

  13. Mycobacteria

    MedlinePlus

    ... NIAID clinical studies on ClinicalTrials.gov . ​ Related Links Tuberculosis Leprosy (Hansen's Disease) National Library of Medicine, MedlinePlus ... coats that can be found throughout the world. Tuberculosis and leprosy (Hansen’s disease) are the best known ...

  14. The new mycobacteria: an update.

    PubMed

    Tortoli, Enrico

    2006-11-01

    The continuous evolution of mycobacterial taxonomy may represent a source of confusion for laboratories and clinicians. Apart from the obvious pathogenic strains of the Mycobacterium tuberculosis complex, Mycobacterium leprae and Mycobacterium ulcerans, the role of other mycobacteria may be associated with varying conditions ranging from contamination to specific disease processes. Of the more than 120 mycobacterial species recognized currently, very few have not been reported as pathogenic in humans or animals. Although the attempt to keep pace with the steadily increasing number of mycobacterial species seems hopeless, a careful review of the recent literature relevant to the newly described species may be advantageous. The aim of this present update is to provide epidemiological and clinical information along with major phenotypic and genotypic characteristics of the species described in the last 3 years.

  15. Natural Disasters and Nontuberculous Mycobacteria

    PubMed Central

    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

  16. Selective Killing of Nonreplicating Mycobacteria

    PubMed Central

    Bryk, Ruslana; Gold, Benjamin; Venugopal, Aditya; Singh, Jasbir; Samy, Raghu; Pupek, Krzysztof; Cao, Hua; Popescu, Carmen; Gurney, Mark; Hotha, Srinivas; Cherian, Joseph; Rhee, Kyu; Ly, Lan; Converse, Paul J.; Ehrt, Sabine; Vandal, Omar; Jiang, Xiuju; Schneider, Jean; Lin, Gang; Nathan, Carl

    2008-01-01

    SUMMARY Antibiotics are typically more effective against replicating rather than nonreplicating bacteria. However, a major need in global health is to eradicate persistent or nonreplicating subpopulations of bacteria such as Mycobacterium tuberculosis (Mtb). Hence, identifying chemical inhibitors that selectively kill bacteria that are not replicating is of practical importance. To address this, we screened for inhibitors of dihydrolipoamide acyltransferase (DlaT), an enzyme required by Mtb to cause tuberculosis in guinea pigs and used by the bacterium to resist nitric oxide-derived reactive nitrogen intermediates, a stress encountered in the host. Chemical screening for inhibitors of Mtb DlaT identified select rhodanines as compounds that almost exclusively kill nonreplicating mycobacteria in synergy with products of host immunity, such as nitric oxide and hypoxia, and are effective on bacteria within macrophages, a cellular reservoir for latent Mtb. Compounds that kill nonreplicating pathogens in cooperation with host immunity could complement the conventional chemotherapy of infectious disease. PMID:18329613

  17. General Overview on Nontuberculous Mycobacteria, Biofilms, and Human Infection

    PubMed Central

    Faria, Sonia; Joao, Ines; Jordao, Luisa

    2015-01-01

    Nontuberculous mycobacteria (NTM) are emergent pathogens whose importance in human health has been growing. After being regarded mainly as etiological agents of opportunist infections in HIV patients, they have also been recognized as etiological agents of several infections on immune-competent individuals and healthcare-associated infections. The environmental nature of NTM and their ability to assemble biofilms on different surfaces play a key role in their pathogenesis. Here, we review the clinical manifestations attributed to NTM giving particular importance to the role played by biofilm assembly. PMID:26618006

  18. [Pulmonary infections with non-tuberculous mycobacteria].

    PubMed

    Fløe, Andreas; Hermansen, Thomas Stig; Lillebæk, Troels; Hilberg, Ole

    2016-06-20

    In recent decades, an increasing incidence of pulmonary infections with non-tuberculous mycobacteria has been reported, primarily affecting patients with structural lung diseases and/or immunosuppression. In Denmark, approximately 100 new cases of infection with non-tuberculous mycobacteria occur yearly, most commonly with Mycobac-terium avium complex. Diagnosis is based on clinical, radiological and microbiological criteria. Treatment is difficult, and outcomes are often poor. Antibiotic treatment should be performed by specialists with reference to international guidelines. PMID:27401987

  19. Rapidly changing climatic conditions for wine grape growing in the Okanagan Valley region of British Columbia, Canada.

    PubMed

    Rayne, Sierra; Forest, Kaya

    2016-06-15

    A statistical analysis was conducted on long-term climate records for sites bordering Okanagan Lake in the Okanagan Valley viticultural region of British Columbia, Canada. Average wine grape growing season temperatures are increasing rapidly in the area over the post-1980 period at rates upwards of 7.0±1.3°C/century. Similar increases in the average dormant season temperature are evident. These temperature changes are likely some of the most extreme observed among the world's wine producing areas during the past few decades. Growing degree day base 10°C (GDD10) has increased by nearly 50% at some locations since the 1970s, resulting in major impacts on the corresponding climate classification for viticulture. If current climate trends continue, the southern and central portions of the region will likely enter Winkler region II within the next few decades, placing them in the same category as well-established warmer wine regions from France, Spain, Italy, and Australia. The large dormant season temperature increases over the last several decades have resulted in the area no longer being a cold season outlier when compared to most other cool-climate viticultural areas. Based on average growing season temperatures, the southern end of Okanagan Lake has moved out of the cool-climate viticultural classification and into the intermediate zone, while the central and northern regions are now at the cool/intermediate viticulture interface, similar to the historical positions of the Rhine Valley in Germany, northern Oregon in the United States, and the Loire Valley, Burgundy-Cote, Burgundy-Beaujolais, and Champagne appelations of France. The corresponding suitable grape species for the area have evolved into warmer region varietals during this time frame, having substantial economic impacts on producers. Increased temperatures are also expected to bring greater threats from agricultural pests, notably Pierce's disease from the bacterium Xylella fastidiosa. PMID:26971218

  20. Comparison of culture methods for isolation of nontuberculous mycobacteria from surface waters.

    PubMed

    Radomski, Nicolas; Cambau, Emmanuelle; Moulin, Laurent; Haenn, Sophie; Moilleron, Régis; Lucas, Françoise S

    2010-06-01

    The environment is the likely source of most nontuberculous mycobacteria (NTM) involved in human infections, especially pulmonary, skin, and soft tissue infections. In order to measure the prevalence of NTM in different aquatic ecosystems, we tried to standardize the culture methods used for surface water testing since many procedures have been described previously. Cultivation of mycobacteria requires long-term incubation in rich media and inactivation of rapidly growing microorganisms whose growth impedes observation of mycobacterial colonies. Consequently, the two criteria used for evaluation of the methods examined were (i) the rate of inhibition of nontarget microorganisms and (ii) the efficiency of recovery of mycobacteria. We compared the competitive growth of Mycobacterium chelonae and M. avium with nontarget microorganisms on rich Middlebrook 7H11-mycobactin medium after treatment by several chemical decontamination methods that included acids, bases, detergent, or cetylpyridinium chloride (CPC) with and without an antibiotic cocktail, either PANTA (40 U/ml polymyxin, 4 microg/ml amphotericin B, 16 microg/ml nalidixic acid, 4 microg/ml trimethoprim, and 4 microg/ml azlocillin) or PANTAV (PANTA plus 10 microg/ml vancomycin). Our results showed that treatment for 30 min with CPC (final concentration, 0.05%) of water concentrated by centrifugation, followed by culture on a rich medium supplemented with PANTA, significantly decreased the growth of nontarget microorganisms (the concentrations were 6.2 +/- 0.4 log(10) CFU/liter on Middlebrook 7H11j medium and 4.2 +/- 0.2 log(10) CFU/liter on Middlebrook 7H11j medium containing PANTA [P < 0.001]), while the effect of this procedure on NTM was not as great (the concentrations of M. chelonae on the two media were 7.0 +/- 0.0 log(10) CFU/liter and 6.9 +/- 0.0 log(10) CFU/liter, respectively, and the concentrations of M. avium were 9.1 +/- 0.0 log(10) CFU/liter and 8.9 +/- 0.0 log(10) CFU/liter, respectively). We

  1. Comparison of Culture Methods for Isolation of Nontuberculous Mycobacteria from Surface Waters▿ †

    PubMed Central

    Radomski, Nicolas; Cambau, Emmanuelle; Moulin, Laurent; Haenn, Sophie; Moilleron, Régis; Lucas, Françoise S.

    2010-01-01

    The environment is the likely source of most nontuberculous mycobacteria (NTM) involved in human infections, especially pulmonary, skin, and soft tissue infections. In order to measure the prevalence of NTM in different aquatic ecosystems, we tried to standardize the culture methods used for surface water testing since many procedures have been described previously. Cultivation of mycobacteria requires long-term incubation in rich media and inactivation of rapidly growing microorganisms whose growth impedes observation of mycobacterial colonies. Consequently, the two criteria used for evaluation of the methods examined were (i) the rate of inhibition of nontarget microorganisms and (ii) the efficiency of recovery of mycobacteria. We compared the competitive growth of Mycobacterium chelonae and M. avium with nontarget microorganisms on rich Middlebrook 7H11-mycobactin medium after treatment by several chemical decontamination methods that included acids, bases, detergent, or cetylpyridinium chloride (CPC) with and without an antibiotic cocktail, either PANTA (40 U/ml polymyxin, 4 μg/ml amphotericin B, 16 μg/ml nalidixic acid, 4 μg/ml trimethoprim, and 4 μg/ml azlocillin) or PANTAV (PANTA plus 10 μg/ml vancomycin). Our results showed that treatment for 30 min with CPC (final concentration, 0.05%) of water concentrated by centrifugation, followed by culture on a rich medium supplemented with PANTA, significantly decreased the growth of nontarget microorganisms (the concentrations were 6.2 ± 0.4 log10 CFU/liter on Middlebrook 7H11j medium and 4.2 ± 0.2 log10 CFU/liter on Middlebrook 7H11j medium containing PANTA [P < 0.001]), while the effect of this procedure on NTM was not as great (the concentrations of M. chelonae on the two media were 7.0 ± 0.0 log10 CFU/liter and 6.9 ± 0.0 log10 CFU/liter, respectively, and the concentrations of M. avium were 9.1 ± 0.0 log10 CFU/liter and 8.9 ± 0.0 log10 CFU/liter, respectively). We propose that this standardized

  2. Malachite Green Interferes with Postantibiotic Recovery of Mycobacteria

    PubMed Central

    Gelman, Ekaterina; McKinney, John D.

    2012-01-01

    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. PMID:22526306

  3. Comparison of culture and qPCR methods in detection of mycobacteria from drinking waters.

    PubMed

    Räsänen, Noora H J; Rintala, Helena; Miettinen, Ilkka T; Torvinen, Eila

    2013-04-01

    Environmental mycobacteria are common bacteria in man-made water systems and may cause infections and hypersensitivity pneumonitis via exposure to water. We compared a generally used cultivation method and a quantitative polymerase chain reaction (qPCR) method to detect mycobacteria in 3 types of drinking waters: surface water, ozone-treated surface water, and groundwater. There was a correlation between the numbers of mycobacteria obtained by cultivation and qPCR methods, but the ratio of the counts obtained by the 2 methods varied among the types of water. The qPCR counts in the drinking waters produced from surface or groundwater were 5 to 34 times higher than culturable counts. In ozone-treated surface waters, both methods gave similar counts. The ozone-treated drinking waters had the highest concentration of assimilable organic carbon, which may explain the good culturability. In warm tap waters, qPCR gave 43 times higher counts than cultivation, but both qPCR counts and culturable counts were lower than those in the drinking waters collected from the same sites. The TaqMan qPCR method is a rapid and sensitive tool for total quantitation of mycobacteria in different types of clean waters. The raw water source and treatments affect both culturability and total numbers of mycobacteria in drinking waters.

  4. Mycobacteria in Finnish cooling tower waters.

    PubMed

    Torvinen, Eila; Suomalainen, Sini; Paulin, Lars; Kusnetsov, Jaana

    2014-04-01

    Evaporative cooling towers are water systems used in, e.g., industry and telecommunication to remove excess heat by evaporation of water. Temperatures of cooling waters are usually optimal for mesophilic microbial growth and cooling towers may liberate massive amounts of bacterial aerosols. Outbreaks of legionellosis associated with cooling towers have been known since the 1980's, but occurrences of other potentially pathogenic bacteria in cooling waters are mostly unknown. We examined the occurrence of mycobacteria, which are common bacteria in different water systems and may cause pulmonary and other soft tissue infections, in cooling waters containing different numbers of legionellae. Mycobacteria were isolated from all twelve cooling systems and from 92% of the 24 samples studied. Their numbers in the positive samples varied from 10 to 7.3 × 10(4) cfu/L. The isolated species included M. chelonae/abscessus, M. fortuitum, M. mucogenicum, M. peregrinum, M. intracellulare, M. lentiflavum, M. avium/nebraskense/scrofulaceum and many non-pathogenic species. The numbers of mycobacteria correlated negatively with the numbers of legionellae and the concentration of copper. The results show that cooling towers are suitable environments for potentially pathogenic mycobacteria. Further transmission of mycobacteria from the towers to the environment needs examination. PMID:23937212

  5. Shrinkage of a rapidly growing tumor by drug-loaded polymersomes: pH-triggered release through copolymer degradation.

    PubMed

    Ahmed, Fariyal; Pakunlu, Refika I; Srinivas, Goundla; Brannan, Aaron; Bates, Frank; Klein, Michael L; Minko, Tamara; Discher, Dennis E

    2006-01-01

    Carrier-mediated delivery of drugs into the cytosol is often limited by either release from the carrier or release from an internalizing endolysosome. Here, loading, delivery, and cytosolic uptake of drug mixtures from degradable polymersomes are shown to exploit both the thick membrane of these block copolymer vesicles and their aqueous lumen as well as pH-triggered release within endolysosomes. Our initial in vivo studies demonstrate growth arrest and shrinkage of rapidly growing tumors after a single intravenous injection of polymersomes composed of poly(ethylene glycol)-polyester. Vesicles are shown to break down into membrane-lytic micelles within hours at 37 degrees C and low pH, although storage at 4 degrees C allows retention of drug for over a month. It is then shown that cell entry of the polymersomes into endolysosomes is followed by copolymer-induced endolysosomal rupture with release of cytotoxic drugs. Above a critical poration concentration (CCPC) that is easily achieved within endolysosomes and that scales with copolymer proportions and molecular weight, the copolymer micelles are seen to disrupt lipid membranes and thereby enhance drug activity. Neutral polymersomes and related macrosurfactant assemblies can thus create novel pathways within cells for controlled release and delivery. PMID:16749866

  6. Miniaturized extinction culturing is the preferred strategy for rapid isolation of fast‐growing methane‐oxidizing bacteria

    PubMed Central

    Hoefman, Sven; van der Ha, David; De Vos, Paul; Boon, Nico; Heylen, Kim

    2012-01-01

    Summary Methane‐oxidizing bacteria (MOB) have a large potential as a microbial sink for the greenhouse gas methane as well as for biotechnological purposes. However, their application in biotechnology has so far been hampered, in part due to the relative slow growth rate of the available strains. To enable the availability of novel strains, this study compares the isolation of MOB by conventional dilution plating with miniaturized extinction culturing, both performed after an initial enrichment step. The extinction approach rendered 22 MOB isolates from four environmental samples, while no MOB could be isolated by plating. In most cases, extinction culturing immediately yielded MOB monocultures making laborious purification redundant. Both type I (Methylomonas spp.) and type II (Methylosinus sp.) MOB were isolated. The isolated methanotrophic diversity represented at least 11 different strains and several novel species based on 16S rRNA gene sequence dissimilarity. These strains possessed the particulate (100%) and soluble (64%) methane monooxygenase gene. Also, 73% of the strains could be linked to a highly active fast‐growing mixed MOB community. In conclusion, miniaturized extinction culturing was more efficient in rapidly isolating numerous MOB requiring little effort and fewer materials, compared with the more widely applied plating procedure. This miniaturized approach allowed straightforward isolation and could be very useful for subsequent screening of desired characteristics, in view of their future biotechnological potential. PMID:22070783

  7. Seroprevalence of 13 common pathogens in a rapidly growing U.S. minority population: Mexican Americans from San Antonio, TX

    PubMed Central

    2011-01-01

    Background Infection risks vary among individuals and between populations. Here we present information on the seroprevalence of 13 common infectious agents in a San Antonio-based sample of Mexican Americans. Mexican Americans represent the largest and most rapidly growing minority population in the U.S., and they are also considered a health disparities population. Methods We analyzed 1227 individuals for antibody titer to Chlamydophila pneumoniae, Helicobacter pylori, Toxoplasma gondii, cytomegalovirus, Epstein-Barr virus, herpes simplex virus-1, herpes simplex virus-2 (HSV-2), human herpesvirus-6 (HHV-6), varicella zoster virus (VZV), adenovirus-36, hepatitis A virus, and influenza A and B. Seroprevalence was examined as a function of sex, age, household income, and education. Results Seroprevalence estimates ranged from 9% for T. gondii to 92% for VZV, and were similar in both sexes except for HSV-2, which was more prevalent in women. Many pathogens exhibited a significant seroprevalence change over the examined age range (15-94 years), with 7 pathogens increasing and HHV-6 decreasing with age. Socioeconomic status significantly correlated with serostatus for some pathogens. Conclusions Our findings demonstrate substantial seroprevalence rates of these common infections in this sample of Mexican Americans from San Antonio, Texas that suffers from high rates of chronic diseases including obesity and type-2 diabetes. PMID:22018212

  8. Recovery of mycobacteria from patients with cystic fibrosis.

    PubMed

    Bange, F C; Kirschner, P; Böttger, E C

    1999-11-01

    Despite decontamination, overgrowth by pseudomonads renders cultural isolation of mycobacteria from respiratory specimens of patients with cystic fibrosis (CF) difficult or impossible. We performed a prospective study by comparing levels of reduction of overgrowth and recovery of mycobacteria using either pretreatment with N-acetyl-L-cysteine (NALC)-NaOH alone or pretreatment with NALC-NaOH and then with oxalic acid. From 406 specimens of 148 CF patients, 11 specimens were positive for mycobacteria, 5 of which grew mycobacteria after decontamination by either procedure. Three specimens grew mycobacteria only after decontamination with NALC-NaOH, whereas three specimens grew mycobacteria only after treatment with NALC-NaOH followed by oxalic acid but were overgrown after decontamination with NALC-NaOH. Thus, inactivation of mycobacteria by the more aggressive oxalic acid treatment offsets its beneficial effect of reducing the proportion of cultures overgrown with microorganisms other than mycobacteria. PMID:10523596

  9. Burden of unidentifiable mycobacteria in a reference laboratory.

    PubMed

    Tortoli, E; Bartoloni, A; Böttger, E C; Emler, S; Garzelli, C; Magliano, E; Mantella, A; Rastogi, N; Rindi, L; Scarparo, C; Urbano, P

    2001-11-01

    Modern identification techniques at the genomic level have greatly improved the taxonomic knowledge of mycobacteria. In adjunct to nucleic acid sequences, mycobacterial identification has been endorsed by investigation of the lipidic patterns of unique mycolic acids in such organisms. In the present investigation, the routine use of high-performance liquid chromatography (HPLC) of mycolic acids, followed by the sequencing of the 16S rRNA, allowed us to select 72 mycobacterial strains, out of 1,035 screened, that do not belong to any of the officially recognized mycobacterial species. Most strains (i.e., 47) were isolated from humans, 13 were from the environment, 3 were from animals, and 9 were from unknown sources. The majority of human isolates were grown from the respiratory tract and were therefore most likely not clinically significant. Some, however, were isolated from sterile sites (blood, pleural biopsy, central venous catheter, or pus). Many isolates, including several clusters of two or more strains, mostly slow growers and scotochromogenic, presented unique genetic and lipidic features. We hope the data reported here, including the results of major conventional identification tests, the HPLC profiles of strains isolated several times, and the whole sequences of the 16S rRNA hypervariable regions of all 72 mycobacteria, may encourage reporting of new cases. The taxonomy of the genus Mycobacterium is, in our opinion, still far from being fully elucidated, and the reporting of unusual strains provides the best background for the recognition of new species. Our report also shows the usefulness of the integration of novel technology to routine diagnosis, especially in cases involving slow-growing microorganisms such as mycobacteria.

  10. Findings of mycobacteria in insectivores and small rodents.

    PubMed

    Fischer, O; Mátlová, L; Bartl, J; Dvorská, L; Melichárek, I; Pavlík, I

    2000-01-01

    The organs of 30 insectivorous mammals and 62 rodents from areas inhabited by people or livestock where cattle paratuberculosis or mycobacterial infections of swine had been found to occur were examined by cultivation during the monitoring of occurrence and spread of mycobacterioses in cattle and swine. Mycobacteria were found in the organs of 3 insectivores (10%) and 6 rodents (9.7%). Mycobacterium chelonae was isolated from the organs of the lesser white-toothed shrew (Crocidura suaveolens) and the common vole (Microtus arvalis), and M. vaccae and M. avium subsp. avium (IS901+, serotype 1) from the organs of the common shrew (Sorex araneus). M. avium subsp. avium (IS901+, serotype 1) was also isolated from the organs of the yellow-necked mouse (Apodemus flavicollis). Slow-growing mycobacteria of group III (according to Runyon) were isolated from the organs of the mouse (Mus musculus sensu lato) and the yellow-necked mouse (A. flavicollis). These findings had no connection with the epizootological situation in the nearby livestock. M. fortuitum was isolated from the organs of the common vole (M. arvalis) caught in a field within easy reach of a swine breeding herd. M. fortuitum was also identified in the lymph nodes and droppings of this swine herd, as well as in the straw, scrapings from the floor of stalls, troughs and banisters, as well as from larvae and imagoes of dipterous insects. These results demonstrate the possibility that insectivores and small rodents can spread the causative agents of mycobacteria in wild and domestic animals.

  11. Rapidly growing black holes and host galaxies in the distant Universe from the Herschel Radio Galaxy Evolution Project

    NASA Astrophysics Data System (ADS)

    Drouart, G.; De Breuck, C.; Vernet, J.; Seymour, N.; Lehnert, M.; Barthel, P.; Bauer, F. E.; Ibar, E.; Galametz, A.; Haas, M.; Hatch, N.; Mullaney, J. R.; Nesvadba, N.; Rocca-Volmerange, B.; Röttgering, H. J. A.; Stern, D.; Wylezalek, D.

    2014-06-01

    We present results from a comprehensive survey of 70 radio galaxies at redshifts 1 growing extremely rapidly, having SFR ≈ 100-5000 M⊙ yr-1 and ṀBH ≈ 1-100 M⊙ yr-1. The mean specific SFRs (sSFR) of radio galaxies at z> 2.5 are higher than the sSFR of typical star forming galaxies over the same redshift range, but are similar or perhaps lower than the galaxy population for radio galaxies at z< 2.5. By comparing the sSFR and the specific ṀBH (sṀBH), we conclude that black holes in radio loud AGN are already, or soon will be, overly massive compared to their host galaxies in terms of expectations from the local MBH-MGal relation. In order to catch up with the black hole, the galaxies require about an order of magnitude more time to grow in mass at the observed SFRs compared to the time the black hole is actively accreting

  12. Mycobacterium sediminis sp. nov. and Mycobacterium arabiense sp. nov., two rapidly growing members of the genus Mycobacterium.

    PubMed

    Zhang, Dao-Feng; Chen, Xiu; Zhang, Xiao-Mei; Zhi, Xiao-Yang; Yao, Ji-Cheng; Jiang, Yi; Xiong, Zhi; Li, Wen-jun

    2013-11-01

    Two novel isolates of rapidly growing, Gram-stain-positive, non-chromogenic species of the genus Mycobacterium, strain YIM M13028(T) from a sediment sample collected from the South China Sea (19° 30.261' N 111° 0.247' E) at a depth of 42 m and strain YIM 121001(T) from a coastal zone sand sample collected in Dubai, United Arab Emirates, were obtained in our laboratory. Their taxonomic positions were determined by a polyphasic approach. Good growth of the two strains was observed at 28 °C and pH 7.0 with 0-2 % NaCl on tryptic soy agar medium. Both strains formed round orange-red colonies, strain YIM M13028(T) had a rough surface, while YIM 121001(T) was smooth. Cellular fatty acids, whole-cell protein profiles and TLC analysis of their mycolic acids show significant differences from reference stains. Phenotypic characteristics and multilocus sequence analysis (MLSA) of 16S rRNA gene, hsp65, rpoB and 16S-23S internal transcribed spacer (ITS) sequences indicated that both strains YIM M13028(T) and YIM 121001(T) belong to the genus Mycobacterium. DNA-DNA hybridization values revealed a low relatedness (<70 %) of the two isolates with the type strains Mycobacterium neoaurum DSM 44074(T) and Mycobacterium hodleri DSM 44183(T). The low DNA-DNA hybridization values (40.4±3.5 %) between strains YIM M13028(T) and YIM 121001(T) and phenotypic distinctiveness indicated that the two strains were representatives of different novel species of the genus Mycobacterium. The names proposed for these novel species are Mycobacterium sediminis sp. nov. and Mycobacterium arabiense sp. nov., and the type strains are YIM M13028(T) ( = DSM 45643(T) = KCTC 19999(T)) and YIM 121001(T) ( = DSM 45768(T) = JCM 18538(T)), respectively.

  13. Effects of landscape change on fish assemblage structure in a rapidly growing metropolitan area in North Carolina, USA

    USGS Publications Warehouse

    Kennen, J.G.; Chang, M.; Tracy, B.H.

    2005-01-01

    We evaluated a comprehensive set of natural and land-use attributes that represent the major facets of urban development at fish monitoring sites in the rapidly growing Raleigh-Durham, North Carolina metropolitan area. We used principal component and correlation analysis to obtain a nonredundant subset of variables that extracted most variation in the complete set. With this subset of variables, we assessed the effect of urban growth on fish assemblage structure. We evaluated variation in fish assemblage structure with nonmetric multidimensional scaling (NMDS). We used correlation analysis to identify the most important environmental and landscape variables associated with significant NMDS axes. The second NMDS axis is related to many indices of land-use/land-cover change and habitat. Significant correlations with proportion of largest forest patch to total patch size (r = -0.460, P < 0.01), diversity of patch types (r = 0.554, P < 0.001), and population density (r = 0.385, P < 0.05) helped identify NMDS axis 2 as a disturbance gradient. Positive and negative correlations between the abundance of redbreast sunfish Lepomis auritus and bluehead chub Nocomis leptocephalus, respectively, and NMDS axis 2 also were evident. The North Carolina index of biotic integrity and many of its component metrics were highly correlated with urbanization. These results indicate that aquatic ecosystem integrity would be optimized by a comprehensive integrated management strategy that includes the preservation of landscape function by maximizing the conservation of contiguous tracts of forested lands and vegetative cover in watersheds. ?? 2005 by the American Fisheries Society.

  14. Development of an In Vitro Assay for Detection of Drug-Induced Resuscitation-Promoting-Factor-Dependent Mycobacteria

    PubMed Central

    Loraine, Jessica; Pu, Feifei; Turapov, Obolbek

    2016-01-01

    Tuberculosis is a major infectious disease that requires prolonged chemotherapy with a combination of four drugs. Here we present data suggesting that treatment of Mycobacterium tuberculosis, the causative agent of tuberculosis, and Mycobacterium smegmatis, a model organism widely used for the screening of antituberculosis agents, with first-line drugs resulted in the generation of substantial populations that could be recovered only by the addition of a culture supernatant from growing mycobacteria. These bacilli failed to grow in standard media, resulting in significant underestimation of the numbers of viable mycobacteria in treated samples. We generated M. smegmatis strains overexpressing M. tuberculosis resuscitation-promoting factors (Rpfs) and demonstrated their application for the detection of Rpf-dependent mycobacteria generated after drug exposure. Our data offer novel opportunities for validation of the sterilizing activity of antituberculosis agents. PMID:27503641

  15. Application of the Sherlock Mycobacteria Identification System using high-performance liquid chromatography in a clinical laboratory.

    PubMed

    Kellogg, J A; Bankert, D A; Withers, G S; Sweimler, W; Kiehn, T E; Pfyffer, G E

    2001-03-01

    There is a growing need for a more accurate, rapid, and cost-effective alternative to conventional tests for identification of clinical isolates of Mycobacterium species. Therefore, the ability of the Sherlock Mycobacteria Identification System (SMIS; MIDI, Inc.) using computerized software and a Hewlett-Packard series 1100 high-performance liquid chromatograph to identify mycobacteria was compared to identification using phenotypic characteristics, biochemical tests, probes (Gen-Probe, Inc.), gas-liquid chromatography, and, when necessary, PCR-restriction enzyme analysis of the 65-kDa heat shock protein gene and 16S rRNA gene sequencing. Culture, harvesting, saponification, extraction, derivatization, and chromatography were performed following MIDI's instructions. Of 370 isolates and stock cultures tested, 327 (88%) were given species names by the SMIS. SMIS software correctly identified 279 of the isolates (75% of the total number of isolates and 85% of the named isolates). The overall predictive value of accuracy (correct calls divided by total calls of a species) for SMIS species identification was 85%, ranging from only 27% (3 of 11) for M. asiaticum to 100% for species or groups including M. malmoense (8 of 8), M. nonchromogenicum (11 of 11), and the M. chelonae-abscessus complex (21 of 21). By determining relative peak height ratios (RPHRs) and relative retention times (RRTs) of selected mycolic acid peaks, as well as phenotypic properties, all 48 SMIS-misidentified isolates and 39 (91%) of the 43 unidentified isolates could be correctly identified. Material and labor costs per isolate were $10.94 for SMIS, $26.58 for probes, and $42.31 for biochemical identification. The SMIS, combined with knowledge of RPHRs, RRTs, and phenotypic characteristics, offers a rapid, reasonably accurate, cost-effective alternative to more traditional methods of mycobacterial species identification.

  16. The environmental pathogen Mycobacterium ulcerans grows in amphibian cells at low temperatures.

    PubMed

    Drancourt, Michel; Jarlier, Vincent; Raoult, Didier

    2002-12-01

    Mycobacterium ulcerans, the etiological agent of Buruli ulcers, is an environmental pathogen. We cultivated it in an amphibian (XTC-2) cell line that grows at 28 degrees C. By counting of Ziehl-Neelsen-stained mycobacteria and by quantitative PCR analysis, we found that M. ulcerans multiplies rapidly in association with XTC-2 cells. Transmission electron microscopy demonstrated the presence of intracellular M. ulcerans microorganisms. These data suggest an intracellular environmental niche, and we propose use of XTC-2 cells for isolation of M. ulcerans from environmental sources.

  17. OCCURRENCE OF NONTUBERCULOUS MYCOBACTERIA IN ENVIRONMENTAL SAMPLES

    EPA Science Inventory

    Nontuberculous mycobacteria (NTM) are a major cause of opportunistic infection in immunocompromised hosts. Because there is no evidence of person-to-person transmission and NTM have been found in drinking water, the environment is considered a likely source of infection. In this ...

  18. EXAMINATION OF BOTTLED WATER FOR NONTUBERCULOUS MYCOBACTERIA

    EPA Science Inventory

    The objective of this study was to examine bottled water for the presence of nontuberculous mycobacteria as a potential source of infection in AIDS patients. Twenty brands of bottled water commonly used in the Los Angeles area were tested for the presence of nontuberculous mycoba...

  19. [Current microbiological methods in the investigation of mycobacteria].

    PubMed

    Richter, E; Andres, S; Hillemann, D

    2015-05-01

    The rapid and reliable detection of tuberculosis is the main goal of microbiological analyses. This is not only of great value for an early diagnosis and early start of an adequate therapy, but also helps to stop transmission and spread of the disease. Prerequisites for successful detection of mycobacteria are careful selection of patient specimens, proper sampling and appropriate shipping. In addition to the classical microbiological methods such as staining for acid-fast bacteria and culture procedures, newer molecular methods are gaining greater importance (PCR; NAT). TB bacteria and resistance-associated mutations can be detected from the specimens directly, providing an early hint about resistant strains. In positive cultures, M. tuberculosis complex and nontuberculous mycobacteria must be discriminated from each other. Drug susceptibility testing (DST) of all first-line drugs has to be performed from one isolate of each patient and repeated if TB bacteria are still isolated after 2 months of therapy. DST of second-line drugs should follow in case of drug resistance or drug intolerance. PMID:25970121

  20. Temporal and intrinsic factors of rifampicin tolerance in mycobacteria.

    PubMed

    Richardson, Kirill; Bennion, Owen T; Tan, Shumin; Hoang, Anh N; Cokol, Murat; Aldridge, Bree B

    2016-07-19

    Mycobacteria grow and divide asymmetrically, creating variability in growth pole age, growth properties, and antibiotic susceptibilities. Here, we investigate the importance of growth pole age and other growth properties in determining the spectrum of responses of Mycobacterium smegmatis to challenge with rifampicin. We used a combination of live-cell microscopy and modeling to prospectively identify subpopulations with altered rifampicin susceptibility. We found two subpopulations that had increased susceptibility. At the initiation of treatment, susceptible cells were either small and at early stages of the cell cycle, or large and in later stages of their cell cycle. In contrast to this temporal window of susceptibility, tolerance was associated with factors inherited at division: long birth length and mature growth poles. Thus, rifampicin response is complex and due to a combination of differences established from both asymmetric division and the timing of treatment relative to cell birth. PMID:27357669

  1. Prospecting Environmental Mycobacteria: Combined Molecular Approaches Reveal Unprecedented Diversity

    PubMed Central

    Pontiroli, Alessandra; Khera, Tanya T.; Oakley, Brian B.; Mason, Sam; Dowd, Scot E.; Travis, Emma R.; Erenso, Girum; Aseffa, Abraham; Courtenay, Orin; Wellington, Elizabeth M. H.

    2013-01-01

    Background Environmental mycobacteria (EM) include species commonly found in various terrestrial and aquatic environments, encompassing animal and human pathogens in addition to saprophytes. Approximately 150 EM species can be separated into fast and slow growers based on sequence and copy number differences of their 16S rRNA genes. Cultivation methods are not appropriate for diversity studies; few studies have investigated EM diversity in soil despite their importance as potential reservoirs of pathogens and their hypothesized role in masking or blocking M. bovis BCG vaccine. Methods We report here the development, optimization and validation of molecular assays targeting the 16S rRNA gene to assess diversity and prevalence of fast and slow growing EM in representative soils from semi tropical and temperate areas. New primer sets were designed also to target uniquely slow growing mycobacteria and used with PCR-DGGE, tag-encoded Titanium amplicon pyrosequencing and quantitative PCR. Results PCR-DGGE and pyrosequencing provided a consensus of EM diversity; for example, a high abundance of pyrosequencing reads and DGGE bands corresponded to M. moriokaense, M. colombiense and M. riyadhense. As expected pyrosequencing provided more comprehensive information; additional prevalent species included M. chlorophenolicum, M. neglectum, M. gordonae, M. aemonae. Prevalence of the total Mycobacterium genus in the soil samples ranged from 2.3×107 to 2.7×108 gene targets g−1; slow growers prevalence from 2.9×105 to 1.2×107 cells g−1. Conclusions This combined molecular approach enabled an unprecedented qualitative and quantitative assessment of EM across soil samples. Good concordance was found between methods and the bioinformatics analysis was validated by random resampling. Sequences from most pathogenic groups associated with slow growth were identified in extenso in all soils tested with a specific assay, allowing to unmask them from the Mycobacterium whole genus, in

  2. Detection of mycobacteria, Mycobacterium avium subspecies, and Mycobacterium tuberculosis complex by a novel tetraplex real-time PCR assay.

    PubMed

    Sevilla, Iker A; Molina, Elena; Elguezabal, Natalia; Pérez, Valentín; Garrido, Joseba M; Juste, Ramón A

    2015-03-01

    Mycobacterium tuberculosis complex, Mycobacterium avium, and many other nontuberculous mycobacteria are worldwide distributed microorganisms of major medical and veterinary importance. Considering the growing epidemiologic significance of wildlife-livestock-human interrelation, developing rapid detection tools of high specificity and sensitivity is vital to assess their presence and accelerate the process of diagnosing mycobacteriosis. Here we describe the development and evaluation of a novel tetraplex real-time PCR for simultaneous detection of Mycobacterium genus, M. avium subspecies, and M. tuberculosis complex in an internally monitored single assay. The method was evaluated using DNA from mycobacterial (n = 38) and nonmycobacterial (n = 28) strains, tissues spiked with different CFU amounts of three mycobacterial species (n = 57), archival clinical samples (n = 233), and strains isolated from various hosts (n = 147). The minimum detectable DNA amount per reaction was 50 fg for M. bovis BCG and M. kansasii and 5 fg for M. avium subsp. hominissuis. When spiked samples were analyzed, the method consistently detected as few as 100 to 1,000 mycobacterial CFU per gram. The sensitivity and specificity values for the panel of clinical samples were 97.5 and 100% using a verified culture-based method as the reference method. The assays performed on clinical isolates confirmed these results. This PCR was able to identify M. avium and M. tuberculosis complex in the same sample in one reaction. In conclusion, the tetraplex real-time PCR we designed represents a highly specific and sensitive tool for the detection and identification of mycobacteria in routine laboratory diagnosis with potential additional uses.

  3. Detection of Mycobacteria, Mycobacterium avium Subspecies, and Mycobacterium tuberculosis Complex by a Novel Tetraplex Real-Time PCR Assay

    PubMed Central

    Molina, Elena; Elguezabal, Natalia; Pérez, Valentín; Garrido, Joseba M.

    2015-01-01

    Mycobacterium tuberculosis complex, Mycobacterium avium, and many other nontuberculous mycobacteria are worldwide distributed microorganisms of major medical and veterinary importance. Considering the growing epidemiologic significance of wildlife-livestock-human interrelation, developing rapid detection tools of high specificity and sensitivity is vital to assess their presence and accelerate the process of diagnosing mycobacteriosis. Here we describe the development and evaluation of a novel tetraplex real-time PCR for simultaneous detection of Mycobacterium genus, M. avium subspecies, and M. tuberculosis complex in an internally monitored single assay. The method was evaluated using DNA from mycobacterial (n = 38) and nonmycobacterial (n = 28) strains, tissues spiked with different CFU amounts of three mycobacterial species (n = 57), archival clinical samples (n = 233), and strains isolated from various hosts (n = 147). The minimum detectable DNA amount per reaction was 50 fg for M. bovis BCG and M. kansasii and 5 fg for M. avium subsp. hominissuis. When spiked samples were analyzed, the method consistently detected as few as 100 to 1,000 mycobacterial CFU per gram. The sensitivity and specificity values for the panel of clinical samples were 97.5 and 100% using a verified culture-based method as the reference method. The assays performed on clinical isolates confirmed these results. This PCR was able to identify M. avium and M. tuberculosis complex in the same sample in one reaction. In conclusion, the tetraplex real-time PCR we designed represents a highly specific and sensitive tool for the detection and identification of mycobacteria in routine laboratory diagnosis with potential additional uses. PMID:25588660

  4. Antimicrobial Peptides in Innate Immunity against Mycobacteria.

    PubMed

    Shin, Dong-Min; Jo, Eun-Kyeong

    2011-10-01

    Antimicrobial peptides/proteins are ancient and naturallyoccurring antibiotics in innate immune responses in a variety of organisms. Additionally, these peptides have been recognized as important signaling molecules in regulation of both innate and adaptive immunity. During mycobacterial infection, antimicrobial peptides including cathelicidin, defensin, and hepcidin have antimicrobial activities against mycobacteria, making them promising candidates for future drug development. Additionally, antimicrobial peptides act as immunomodulators in infectious and inflammatory conditions. Multiple crucial functions of cathelicidins in antimycobacterial immune defense have been characterized not only in terms of direct killing of mycobacteria but also as innate immune regulators, i.e., in secretion of cytokines and chemokines, and mediating autophagy activation. Defensin families are also important during mycobacterial infection and contribute to antimycobacterial defense and inhibition of mycobacterial growth both in vitro and in vivo. Hepcidin, although its role in mycobacterial infection has not yet been characterized, exerts antimycobacterial effects in activated macrophages. The present review focuses on recent efforts to elucidate the roles of host defense peptides in innate immunity to mycobacteria.

  5. Mycobacteria inactivation using Engineered Water Nanostructures (EWNS)

    PubMed Central

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

    2015-01-01

    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. From the Clinical Editor 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. PMID:24632246

  6. [Application of mass spectrometry in mycobacteria].

    PubMed

    Alcaide, Fernando; Palop-Borrás, Begoña; Domingo, Diego; Tudó, Griselda

    2016-06-01

    To date, more than 170 species of mycobacteria have been described, of which more than one third may be pathogenic to humans, representing a significant workload for microbiology laboratories. These species must be identified in clinical practice, which has long been a major problem due to the shortcomings of conventional (phenotypic) methods and the limitations and complexity of modern methods largely based on molecular biology techniques. The aim of this review was to briefly describe different aspects related to the use of MALDI-TOF (matrix-assisted laser desorption ionization time-of-flight) mass spectrometry (MS) for the identification of mycobacteria. Several difficulties are encountered with the use of this methodology in these microorganisms mainly due to the high pathogenicity of some mycobacteria and the peculiar structure of their cell wall, requiring inactivation and special protein extraction protocols. We also analysed other relevant aspects such as culture media, the reference methods employed (gold standard) in the final identification of the different species, the cut-off used to accept data as valid, and the databases of the different mass spectrometry systems available. MS has revolutionized diagnosis in modern microbiology; however, specific improvements are needed to consolidate the use of this technology in mycobacteriology.

  7. [Application of mass spectrometry in mycobacteria].

    PubMed

    Alcaide, Fernando; Palop-Borrás, Begoña; Domingo, Diego; Tudó, Griselda

    2016-06-01

    To date, more than 170 species of mycobacteria have been described, of which more than one third may be pathogenic to humans, representing a significant workload for microbiology laboratories. These species must be identified in clinical practice, which has long been a major problem due to the shortcomings of conventional (phenotypic) methods and the limitations and complexity of modern methods largely based on molecular biology techniques. The aim of this review was to briefly describe different aspects related to the use of MALDI-TOF (matrix-assisted laser desorption ionization time-of-flight) mass spectrometry (MS) for the identification of mycobacteria. Several difficulties are encountered with the use of this methodology in these microorganisms mainly due to the high pathogenicity of some mycobacteria and the peculiar structure of their cell wall, requiring inactivation and special protein extraction protocols. We also analysed other relevant aspects such as culture media, the reference methods employed (gold standard) in the final identification of the different species, the cut-off used to accept data as valid, and the databases of the different mass spectrometry systems available. MS has revolutionized diagnosis in modern microbiology; however, specific improvements are needed to consolidate the use of this technology in mycobacteriology. PMID:27389290

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

    PubMed Central

    Ummels, Roy; Abdallah, Abdallah M.; Kuiper, Vincent; Aâjoud, Anouar; Sparrius, Marion; Naeem, Raeece; Spaink, Herman P.; van Soolingen, Dick; Pain, Arnab

    2014-01-01

    ABSTRACT 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. PMID:25249284

  9. Evaluation of MALDI Biotyper Mycobacteria Library v3.0 for Identification of Nontuberculous Mycobacteria

    PubMed Central

    Ruiz-Serrano, M. Jesús; Ruiz, Adrián; Timke, Markus; Kostrzewa, Markus; Bouza, Emilio

    2016-01-01

    Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) has demonstrated its ability to promptly identify nontuberculous mycobacteria using the Mycobacteria Library v2.0. However, some species are particularly difficult to identify reliably using this database, providing a low log(score). In this study, the identification power of an updated Mycobacteria Library (v3.0) has been evaluated. Overall, 109 NTM isolates were analyzed with both databases. The v3.0 database allowed a high-level confidence in the identification [log(score) value, ≥1.8] of 91.7% of the isolates versus 83.5% with the v2.0 version (P < 0.01). PMID:26842704

  10. Looking in amoebae as a source of mycobacteria.

    PubMed

    Drancourt, M

    2014-12-01

    Mycobacteria exhibit various relationships with amoebae, ranging from the killing of one partner by the other one, to amoebae hosting mycobacteria in trophozoites and cysts. This observation indicates that poorly described biological factors affect the relationships, including mycobacterial cell-wall glycolipids and the size of the mycobacteria. Experimental observations indicate that a majority of environmental, opportunistic mycobacteria but also obligate pathogens including Mycobacterium tuberculosis, Mycobacterium leprae and Mycobacterium ulcerans are inter-amoebal organisms. Amoebae may give opportunities for genetic exchanges between mycobacteria, sympatric intra-amoebal organisms and the amoebae themselves. Amoebae clearly protect opportunistic mycobacterial pathogens during their environmental life but their role for obligate mycobacterial infection remains to be established. Accordingly, water was the source for emerging, community-acquired and health care-associated infection with amoeba-resisting mycobacteria of the Mycobacterium avium, Mycobacterium abscessus and Mycobacterium fortuitum groups, among others. Amoebae are organisms where mycobacteria can be found and, accordingly, amoeba co-culture can be used for the isolation of mycobacteria from environmental and clinical specimens. Looking in amoebae may help recovering new species of mycobacteria.

  11. Growing Pains from Rapid Growth: A Historical Case Study of George Fox University from 1983 to 2003

    ERIC Educational Resources Information Center

    Railsback, Gary L.

    2007-01-01

    This article is a historical case study of George Fox University (GFU) in Newberg, Oregon. Using organizational lifecycle as a theoretical framework, George Fox University had a long and delayed childhood in that it remained a small and struggling institution for most of the 20th century, and then experienced rapid growth in the late 1980s. This…

  12. Search for mycobacteria in interstitial cystitis using mycobacteria-specific DNA probes with signal amplification by polymerase chain reaction.

    PubMed

    Hampson, S J; Christmas, T J; Moss, M T

    1993-09-01

    The aetiology of interstitial cystitis is not known. Various infective agents have been postulated and although recognised as perpetrators of chronic inflammatory conditions, mycobacteria have never been satisfactorily excluded from interstitial cystitis. If present in interstitial cystitis tissue, mycobacteria exist either in very small numbers or in forms which contemporary staining techniques fail to recognise. We used a polymerase chain reaction with mycobacteria-specific DNA probes and found no evidence of mycobacterial involvement in 8 cases of proven interstitial cystitis.

  13. Notes from the field: rapidly growing nontuberculous Mycobacterium wound infections among medical tourists undergoing cosmetic surgeries in the Dominican Republic--multiple states, March 2013-February 2014.

    PubMed

    Schnabel, David; Gaines, Joanna; Nguyen, Duc B; Esposito, Douglas H; Ridpath, Alison; Yacisin, Kari; Poy, Joe A; Mullins, Jocelyn; Burns, Rachel; Lijewski, Virginia; McElroy, Nora P; Ahmad, Nina; Harrison, Cassandra; Parinelli, Ellen J; Beaudoin, Amanda L; Posivak-Khouly, Leah; Pritchard, Scott; Jensen, Bette J; Toney, Nadege C; Moulton-Meissner, Heather A; Nyangoma, Edith N; Barry, Anita M; Feldman, Katherine A; Blythe, David; Perz, Joseph F; Morgan, Oliver W; Kozarsky, Phyllis; Brunette, Gary W; Sotir, Mark

    2014-03-01

    In August 2013, the Maryland Department of Health and Mental Hygiene (MDHMH) was notified of two persons with rapidly growing nontuberculous mycobacterial (RG-NTM) surgical-site infections. Both patients had undergone surgical procedures as medical tourists at the same private surgical clinic (clinic A) in the Dominican Republic the previous month. Within 7 days of returning to the United States, both sought care for symptoms that included surgical wound abscesses, clear fluid drainage, pain, and fever. Initial antibiotic therapy was ineffective. Material collected from both patients' wounds grew Mycobacterium abscessus exhibiting a high degree of antibiotic resistance characteristic of this organism.

  14. Rapid assessment of ceftazidime, ciprofloxacin, and gentamicin susceptibility in exponentially-growing E. coli cells by means of flow cytometry.

    PubMed

    Walberg, M; Gaustad, P; Steen, H B

    1997-02-01

    Exponentially growing E. coli cells were cultivated in the presence of ceftazidime, ciprofloxacin, and gentamicin in concentrations ranging from 0.5-8 minimal inhibitory concentration (MIC), permeabilized by means of cold shock in EDTA/azide, and stained with the DNA-specific dye combination of ethidium bromide and mithramycin before the fluorescence, light scattering, and cell number were measured flow-cytometrically. In order to evaluate the applicability of the cold-shock procedure, cells were also permeabillized by 70% ethanol. Permeabilization by cold shock, which eliminates washing of the cells, reduced the preparation time to <5 min. A statistically significant increase in light scattering and fluorescence, i.e., cell size and DNA content, could be detected already after 30 min of ceftazidime and ciprofloxacin exposure, even at sub-MIC concentrations. The results obtained with these drugs with cold-shock permeabilization were similar to those seen with ethanol fixation. For gentamicin-treated cells, however, a majority of the cells lost their fluorescence after cold shock. In gentamicin-treated cells fixed in ethanol, there was no consistent effect on either light scattering or fluorescence; however, we observed a substantial fragmentation and leakage of DNA in such cells. The cell proliferation was completely inhibited within 30 min of gentamicin incubation. For all three drugs, loss of light scattering and DNA were associated with cellular disintegration, i.e., reduced viability. The present results demonstrate that effects of ceftazidime, ciprofloxacin, and gentamicin on E. coli can be detected by flow cytometry within 1 h from the beginning of drug exposure to the completed measurement. PMID:9012384

  15. An aerosol climatology for a rapidly growing arid region (southern Arizona): Major aerosol species and remotely sensed aerosol properties

    PubMed Central

    Sorooshian, Armin; Wonaschütz, Anna; Jarjour, Elias G.; Hashimoto, Bryce I.; Schichtel, Bret A.; Betterton, Eric A.

    2014-01-01

    This study reports a comprehensive characterization of atmospheric aerosol particle properties in relation to meteorological and back trajectory data in the southern Arizona region, which includes two of the fastest growing metropolitan areas in the United States (Phoenix and Tucson). Multiple data sets (MODIS, AERONET, OMI/TOMS, MISR, GOCART, ground-based aerosol measurements) are used to examine monthly trends in aerosol composition, aerosol optical depth (AOD), and aerosol size. Fine soil, sulfate, and organics dominate PM2.5 mass in the region. Dust strongly influences the region between March and July owing to the dry and hot meteorological conditions and back trajectory patterns. Because monsoon precipitation begins typically in July, dust levels decrease, while AOD, sulfate, and organic aerosol reach their maximum levels because of summertime photochemistry and monsoon moisture. Evidence points to biogenic volatile organic compounds being a significant source of secondary organic aerosol in this region. Biomass burning also is shown to be a major contributor to the carbonaceous aerosol budget in the region, leading to enhanced organic and elemental carbon levels aloft at a sky-island site north of Tucson (Mt. Lemmon). Phoenix exhibits different monthly trends for aerosol components in comparison with the other sites owing to the strong influence of fossil carbon and anthropogenic dust. Trend analyses between 1988 and 2009 indicate that the strongest statistically significant trends are reductions in sulfate, elemental carbon, and organic carbon, and increases in fine soil during the spring (March–May) at select sites. These results can be explained by population growth, land-use changes, and improved source controls. PMID:24707452

  16. Pristinamycin-inducible gene regulation in mycobacteria.

    PubMed

    Forti, Francesca; Crosta, Andrea; Ghisotti, Daniela

    2009-03-25

    In this work the Pip-inducible system, already used in eukaryotes, was tested in mycobacteria. This system is based on the Streptomyces coelicolor Pip repressor, the Streptomyces pristinaespiralis ptr promoter and the inducer pristinamycin I. By cloning in an integrative plasmid the ptr promoter upstream of the lacZ reporter gene and the pip gene under the control of a constitutive mycobacterial promoter, we demonstrated that the ptr promoter activity increased up to 50-fold in Mycobacterium smegmatis and up to 400-fold in Mycobacterium tuberculosis, in dependence on pristinamycin I concentration, and that the promoter was fully repressed in the absence of the inducer. Three mycobacterial genes were cloned under pptr-Pip control, both in sense and antisense direction; both proteins and antisense RNAs could be over-expressed, the antisenses causing a partial reduction of the amount of the targeted proteins. This system was used to obtain two M. tuberculosis conditional mutants in the fadD32 and pknB genes: the mutant strains grew only in the presence of the inducer pristinamycin I. Thus it showed to be an effective inducible system in mycobacteria. PMID:19428723

  17. Mycobacteria isolated from Chesapeake Bay fish.

    PubMed

    Stine, C B; Kane, A S; Baya, A M

    2010-01-01

    Mycobacteriosis in fish can result in ulcers, emaciation, and in some cases death. Mycobacteria have been previously isolated from a variety of Chesapeake Bay fish species, and the current study was designed to identify potential host specificity and location fidelity of mycobacterial isolates. Mycobacteria were isolated from wild fish of the Chesapeake Bay collected from the Upper Bay, the Choptank River, Herring Bay, the Chicamacomico River, the Pocomoke River and the Potomac River in 2003-2006. Mycobacterial isolates were recovered from striped bass, Morone saxatilis, Atlantic menhaden, Brevoortia tyrannus, white perch, Morone americana, summer flounder, Paralichthys dentatus, spot, Leiostomus xanthurus, largemouth bass, Micropterus salmoides, channel catfish, Ictalurus punctatus, common carp, Cyprinus carpio carpio, spotted seatrout, Cynoscion nebulosus, killifish, Fundulus sp., blueback herring, Alosa aestivalis, American gizzard shad, Dorosoma cepedianum and American silver perch, Bairdiella chrysoura. Twenty-nine well-defined mycobacterial groups resulted from gas chromatography dendrogram clustering of isolates. The majority of groups included more than one host species and more than one site of collection. However, four groups contained only striped bass isolates, three of which were similar to M. shottsii. Therefore, multiple Chesapeake Bay fish species are colonized with multiple mycobacterial isolates, of which few appear to be host or location specific. PMID:19909394

  18. Autophagy as an innate defense against mycobacteria.

    PubMed

    Jo, Eun-Kyeong

    2013-03-01

    Over the past several years, much has been revealed about the roles of autophagy and the mechanisms by which the autophagic pathway activates the host innate effector response against Mycobacterium tuberculosis (Mtb) infection. In response to invading mycobacteria, the host innate immune system not only recognizes pathogen motifs through innate receptors, it also produces appropriate effector proteins, including cytokines. These innate signals activate or regulate autophagic pathways during infection. It is now clear that vitamin D and functional vitamin D receptor signaling are critical in the activation of autophagic defenses against Mtb in human cells. Immunity-related GTPase family M proteins, including the cationic antimicrobial protein cathelicidin and autophagic receptor p62, participate in autophagic pathways that enhance antimicrobial activity against mycobacteria. Moreover, reactive oxygen species mediate antibacterial autophagy and successful antimicrobial responses during antibiotic chemotherapy. Recent work has also shown that pathogenic Mtb can be targeted by selective autophagy through an ESX-1 type VII secretion system. Here, we review the triggers, host factors, and intracellular pathways that regulate host autophagy and its impact on antimicrobial host defenses during mycobacterial infection.

  19. Mycobacteria isolated from Chesapeake Bay fish.

    PubMed

    Stine, C B; Kane, A S; Baya, A M

    2010-01-01

    Mycobacteriosis in fish can result in ulcers, emaciation, and in some cases death. Mycobacteria have been previously isolated from a variety of Chesapeake Bay fish species, and the current study was designed to identify potential host specificity and location fidelity of mycobacterial isolates. Mycobacteria were isolated from wild fish of the Chesapeake Bay collected from the Upper Bay, the Choptank River, Herring Bay, the Chicamacomico River, the Pocomoke River and the Potomac River in 2003-2006. Mycobacterial isolates were recovered from striped bass, Morone saxatilis, Atlantic menhaden, Brevoortia tyrannus, white perch, Morone americana, summer flounder, Paralichthys dentatus, spot, Leiostomus xanthurus, largemouth bass, Micropterus salmoides, channel catfish, Ictalurus punctatus, common carp, Cyprinus carpio carpio, spotted seatrout, Cynoscion nebulosus, killifish, Fundulus sp., blueback herring, Alosa aestivalis, American gizzard shad, Dorosoma cepedianum and American silver perch, Bairdiella chrysoura. Twenty-nine well-defined mycobacterial groups resulted from gas chromatography dendrogram clustering of isolates. The majority of groups included more than one host species and more than one site of collection. However, four groups contained only striped bass isolates, three of which were similar to M. shottsii. Therefore, multiple Chesapeake Bay fish species are colonized with multiple mycobacterial isolates, of which few appear to be host or location specific.

  20. A Multi-Level Approach to Modeling Rapidly Growing Mega-Regions as a Coupled Human-Natural System

    NASA Astrophysics Data System (ADS)

    Koch, J. A.; Tang, W.; Meentemeyer, R. K.

    2013-12-01

    concept of our modeling approach and describe its strengths and weaknesses. We furthermore use empirical data for the states of North and South Carolina to demonstrate how the modeling framework can be applied to a large, heterogeneous study system with diverse decision-making agents. Grimm et al. (2005) Pattern-Oriented Modeling of Agent-Based Complex Systems: Lessons from Ecology. Science 310, 987-991. Liu et al. (2013) Framing Sustainability in a Telecoupled World. Ecology and Society 18(2), 26. Meentemeyer et al. (2013) FUTURES: Multilevel Simulations of Merging Urban-Rural Landscape Structure Using a Stochastic Patch-Growing Algorithm. Annals of the Association of American Geographers 103(4), 785-807.

  1. A Framework Predicting Water Availability in a Rapidly Growing, Semi-Arid Region under Future Climate Change

    NASA Astrophysics Data System (ADS)

    Han, B.; Benner, S. G.; Glenn, N. F.; Lindquist, E.; Dahal, K. R.; Bolte, J.; Vache, K. B.; Flores, A. N.

    2014-12-01

    Climate change can lead to dramatic variations in hydrologic regime, affecting both surface water and groundwater supply. This effect is most significant in populated semi-arid regions where water availability are highly sensitive to climate-induced outcomes. However, predicting water availability at regional scales, while resolving some of the key internal variability and structure in semi-arid regions is difficult due to the highly non-linearity relationship between rainfall and runoff. In this study, we describe the development of a modeling framework to evaluate future water availability that captures elements of the coupled response of the biophysical system to climate change and human systems. The framework is built under the Envision multi-agent simulation tool, characterizing the spatial patterns of water demand in the semi-arid Treasure Valley area of Southwest Idaho - a rapidly developing socio-ecological system where urban growth is displacing agricultural production. The semi-conceptual HBV model, a population growth and allocation model (Target), a vegetation state and transition model (SSTM), and a statistically based fire disturbance model (SpatialAllocator) are integrated to simulate hydrology, population and land use. Six alternative scenarios are composed by combining two climate change scenarios (RCP4.5 and RCP8.5) with three population growth and allocation scenarios (Status Quo, Managed Growth, and Unconstrained Growth). Five-year calibration and validation performances are assessed with Nash-Sutcliffe efficiency. Irrigation activities are simulated using local water rights. Results show that in all scenarios, annual mean stream flow decreases as the projected rainfall increases because the projected warmer climate also enhances water losses to evapotranspiration. Seasonal maximum stream flow tends to occur earlier than in current conditions due to the earlier peak of snow melting. The aridity index and water deficit generally increase in the

  2. FORMATION OF INTRACYTOPLASMIC MEMBRANE SYSTEM OF MYCOBACTERIA RELATED TO CELL DIVISION

    PubMed Central

    Imaeda, Tamotsu; Ogura, Mituo

    1963-01-01

    Imaeda, Tamotsu (Instituto Venezolano de Investigaciones Científicas, Caracas, Venezuela) and Mitua Ogura. Formation of intracytoplasmic membrane system of mycobacteria related to cell division. J. Bacteriol. 85:150–163. 1963.—Mycobacterium leprae, M. lepraemurium, and a Mycobacterium sp. were observed with an electron microscope. In these bacilli, the three-dimensional structure of the intracytoplasmic membrane system consists of tubular infoldings of the invaginated plasma membrane. The moderately dense substance, presumably representing the cell-wall precursor, is found in the membranous system, especially in the rapid growth phase of mycobacteria. This system always shows an intimate relationship with cell division. A low-density zone, probably corresponding to the low-density substance which coats the cell wall, appears in the connecting regions of the system and in the longitudinal portion of the cell wall. These zones extend centripetally, and the separation of the cell wall occurs after the two zones meet. Based on these results, we hypothesize that the intracytoplasmic membrane system may produce cell-wall material during cell division of mycobacteria. Images PMID:13956365

  3. PCR based detection of mycobacteria in paraffin wax embedded material routinely processed for morphological examination.

    PubMed Central

    Frevel, T; Schäfer, K L; Tötsch, M; Böcker, W; Dockhorn-Dworniczak, B

    1999-01-01

    BACKGROUND: The incidence of mycobacterial infections has increased during the past five years. A prompt diagnosis is indispensable for initiating appropriate treatment. Because culturing of mycobacteria takes three to six weeks and sensitivity of microscopic detection of acid fast bacilli is low, amplification methods provide promising possibilities. Recently, the polymerase chain reaction (PCR) has been shown to be useful for confirming a mycobacterial infection, especially in cases with unexpected histological findings or lack of suitable material for culturing. AIMS: To evaluate the impact of PCR based techniques in the detection of mycobacterial infections in uncultured routine histological specimens as an alternative to surgical pathology. METHODS: Two hundred and twenty nine formalin fixed and paraffin wax embedded samples from 141 patients with clinical or histological suspicion of a mycobacterial infection were investigated using three different PCR assays and Southern blotting. PCR results were compared with histology and culture and the patients' clinical findings. RESULTS: When using culture as the reference method, the sensitivity for the detection of mycobacteria of the tuberculosis complex was 90%, specificity was 92%, the positive predictive value was 81%, and the negative predictive value was 96%. The sensitivity for the detection of nontuberculous mycobacteria was 100% and specificity was 78%, the positive predictive value was 26%, and the negative predictive value was 100%. The patients' clinical findings supported the PCR positive results, indicating a mycobacterial infection in 11 of 18 initially culture negative cases and in 21 of 35 PCR positive cases without culture results. CONCLUSIONS: These results indicate that PCR based techniques are sensitive, specific, and rapid methods for the detection of mycobacteria in routinely processed paraffin wax embedded and formalin fixed histological samples. PMID:10748878

  4. Proteomics approach to understand reduced clearance of mycobacteria and high viral titers during HIV-mycobacteria co-infection.

    PubMed

    Ganji, Rakesh; Dhali, Snigdha; Rizvi, Arshad; Sankati, Swetha; Vemula, Mani Harika; Mahajan, Gaurang; Rapole, Srikanth; Banerjee, Sharmistha

    2016-03-01

    Environmental mycobacteria, highly prevalent in natural and artificial (including chlorinated municipal water) niches, are emerging as new threat to human health, especially to HIV-infected population. These seemingly harmless non-pathogenic mycobacteria, which are otherwise cleared, establish as opportunistic infections adding to HIV-associated complications. Although immune-evading strategies of pathogenic mycobacteria are known, the mechanisms underlying the early events by which opportunistic mycobacteria establish infection in macrophages and influencing HIV infection are unclear. Proteomics of phagosome-enriched fractions from Mycobacterium bovis Bacillus Calmette-Guérin (BCG) mono-infected and HIV-M. bovis BCG co-infected THP-1 cells by LC-MALDI-MS/MS revealed differential distribution of 260 proteins. Validation of the proteomics data showed that HIV co-infection helped the survival of non-pathogenic mycobacteria by obstructing phagosome maturation, promoting lipid biogenesis and increasing intracellular ATP equivalents. In turn, mycobacterial co-infection up-regulated purinergic receptors in macrophages that are known to support HIV entry, explaining increased viral titers during co-infection. The mutualism was reconfirmed using clinically relevant opportunistic mycobacteria, Mycobacterium avium, Mycobacterium kansasii and Mycobacterium phlei that exhibited increased survival during co-infection, together with increase in HIV titers. Additionally, the catalogued proteins in the study provide new leads that will significantly add to the understanding of the biology of opportunistic mycobacteria and HIV coalition. PMID:26332641

  5. Mycobacteria Clumping Increase Their Capacity to Damage Macrophages

    PubMed Central

    Brambilla, Cecilia; Llorens-Fons, Marta; Julián, Esther; Noguera-Ortega, Estela; Tomàs-Martínez, Cristina; Pérez-Trujillo, Miriam; Byrd, Thomas F.; Alcaide, Fernando; Luquin, Marina

    2016-01-01

    The rough morphotypes of non-tuberculous mycobacteria have been associated with the most severe illnesses in humans. This idea is consistent with the fact that Mycobacterium tuberculosis presents a stable rough morphotype. Unlike smooth morphotypes, the bacilli of rough morphotypes grow close together, leaving no spaces among them and forming large aggregates (clumps). Currently, the initial interaction of macrophages with clumps remains unclear. Thus, we infected J774 macrophages with bacterial suspensions of rough morphotypes of M. abscessus containing clumps and suspensions of smooth morphotypes, primarily containing isolated bacilli. Using confocal laser scanning microscopy and electron microscopy, we observed clumps of at least five rough-morphotype bacilli inside the phagocytic vesicles of macrophages at 3 h post-infection. These clumps grew within the phagocytic vesicles, killing 100% of the macrophages at 72 h post-infection, whereas the proliferation of macrophages infected with smooth morphotypes remained unaltered at 96 h post-infection. Thus, macrophages phagocytose large clumps, exceeding the bactericidal capacities of these cells. Furthermore, proinflammatory cytokines and granuloma-like structures were only produced by macrophages infected with rough morphotypes. Thus, the present study provides a foundation for further studies that consider mycobacterial clumps as virulence factors. PMID:27757105

  6. Epidemiology of nontuberculous mycobacteria, an emerging environmental pathogen

    EPA Science Inventory

    Nontuberculous mycobacteria (NTM) is an environmentally transmitted pathogen primarily associated with water and soil exposure. It is increasingly recognized in the developed world and may manifest as infection or colonization of multiple anatomic sites. Nontuberculous mycobacter...

  7. Resistance mechanisms and drug susceptibility testing of nontuberculous mycobacteria.

    PubMed

    van Ingen, Jakko; Boeree, Martin J; van Soolingen, Dick; Mouton, Johan W

    2012-06-01

    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, Mycobacterium kansasii) and rapid growers (e.g. Mycobacterium abscessus, Mycobacterium fortuitum). In general, drug treatment is long, costly, and often associated with drug-related toxicities; outcome of drug treatment is poor and is likely related to the high levels of natural antibiotic resistance in NTM. The role of drug susceptibility testing (DST) in the choice of agents for antimicrobial treatment of NTM disease, mainly that by slow growers, remains subject of debate. There are important discrepancies between drug susceptibility measured in vitro and the activity of the drug observed in vivo. In part, these discrepancies derive from laboratory technical issues. There is still no consensus on a standardized method. With the increasing clinical importance of NTM disease, DST of NTM is again in the spotlight. This review provides a comprehensive overview of the mechanisms of drug resistance in NTM, phenotypic methods for testing susceptibility in past and current use for DST of NTM, as well as molecular approaches to assess drug resistance.

  8. Combined rapid maxillary expansion and protraction facemask in the treatment of Class III malocclusions in growing children: a prospective long-term study.

    PubMed

    Williams, M D; Sarver, D M; Sadowsky, P L; Bradley, E

    1997-12-01

    A prospective study of 28 growing children (mean age of 8 years 3 months) with Class III malocclusions was consecutively treated using rapid maxillary expansion and maxillary protraction. All patients were treated from a negative overjet to a positive overjet and from a Class III dental malocclusion to a Class I dental relationship. For each patient, a lateral cephalogram was taken before treatment (T1), immediately posttreatment (T2), and after an observation period (T3) averaging 2 years 5 months. Using analysis of variance, the cephalograms were analyzed to determine skeletal and dental changes resulting from treatment. Long-term changes (2 years 5 month observation period) were also evaluated. Results showed that immediately posttreatment, the maxilla moved anteriorly a mean of 1.54 mm and Sella-Nasion-A point increased 0.87 degree. The maxillary teeth moved anteriorly 2.73 mm and proclined 5.23 degrees, while the mandible rotated in a downward and backward direction. Long-term, the anterior position of the maxilla was maintained, but some of the Class III correction was lost because of mandibular growth. Comparison of this study's results to Riolo's longitudinal Class I data showed that, overall, rapid palatal expansion and maxillary protraction produced a small orthopedic effect with a moderate dentoalveolar effect which together contributed to the correction of the Class III malocclusion.

  9. Increased serum IgG4 levels and intimal IgG4-positive cell infiltration in rapidly growing aortic aneurysm

    PubMed Central

    Fujita, Shuichi; Nishioka, Nobu; Ito, Takahide; Wada, Yuki; Kakita, Ken; Ozawa, Hideki; Tsuji, Motomu; Katsumata, Takahiro

    2013-01-01

    A 67-year-old Japanese man had been complaining of discomfort in the chest and back and feeling febrile for 2 weeks. Chest computed tomography indicated a thoracic aortic aneurysm. He occasionally showed a high fever (up to 38.0°C), even after hospital admission, irrespective of antibiotic therapy. The patient was found to have elevated serum IgG4 levels (366 mg/dL). The aneurysm demonstrated rapid growth; therefore, rifampicin-soaked woven Dacron synthetic graft replacement was performed 22 days after admission. Immunohistostatining of the resected aorta segment showed an IgG4-positive plasma cell infiltrate within the intimal layer neighboring the cholesterol-rich atheromatous plaque. After surgery, the patient’s serum IgG4 level dropped acutely; however, it did not reach the normal range. The possible role of IgG4 in the development or suppression of aortic remodeling, as well as in atherogenesis, among patients with rapidly growing aortic aneurysm requires further investigation. PMID:27489625

  10. [What terms can be applied to mycobacteria other than M. tuberculosis and M. leprae].

    PubMed

    Casal, Manuel

    2003-01-01

    A review of the terms used to name mycobacteria other than M. tuberculosis and M. leprae was performed. A system using binomial nomenclature is defended. The author comments on the various names applied to mycobacteria over the history of medicine, from 1899 to the present, and the reasons why terms such as environmental mycobacteria or nontuberculous mycobacteria are incorrect and should not be used. In the case that a general name must be chosen for these mycobacteria, the term atypical mycobacteria is advocated. PMID:12809584

  11. Characterization of rifampin-resistance in pathogenic mycobacteria.

    PubMed

    Williams, D L; Waguespack, C; Eisenach, K; Crawford, J T; Portaels, F; Salfinger, M; Nolan, C M; Abe, C; Sticht-Groh, V; Gillis, T P

    1994-10-01

    The emergence of rifampin-resistant strains of pathogenic mycobacteria has threatened the usefulness of this drug in treating mycobacterial diseases. Critical to the treatment of individuals infected with resistant strains is the rapid identification of these strains directly from clinical specimens. It has been shown that resistance to rifampin in Mycobacterium tuberculosis and Mycobacterium leprae apparently involves mutations in the rpoB gene encoding the beta-subunit of the RNA polymerases of these species. DNA sequences were obtained from a 305-bp fragment of the rpoB gene from 110 rifampin-resistant and 10 rifampin-susceptible strains of M. tuberculosis from diverse geographical regions throughout the world. In 102 of 110 rifampin-resistant strains 16 mutations affecting 13 amino acids were observed. No mutations were observed in rifampin-susceptible strains. No association was found between particular mutations in the rpoB gene and drug susceptibility patterns of multidrug-resistant M. tuberculosis strains. Drug-resistant M. tuberculosis strains from the same outbreak and exhibiting the same IS6110 DNA fingerprint and drug susceptibility pattern contained the same mutation in the rpoB gene. However, mutations are not correlated with IS6110 profiling outside of epidemics. The evolution of rifampin resistance as a consequence of mutations in the rpoB gene was documented in a patient who developed rifampin resistance during the course of treatment. Rifampin-resistant strains of M. leprae, Mycobacterium avium, and Mycobacterium africanum contained mutations in the rpoB gene similar to that documented for M. tuberculosis. This information served as the basis for developing a rapid DNA diagnostic assay (PCR-heteroduplex formation) for the detection of rifampin susceptibility of M. tuberculosis.

  12. [Isolation of nontuberculous mycobacteria during colonoscopy].

    PubMed

    Kobayashi, Y; Takano, T; Hirayama, N; Sato, N; Shimoide, H

    1995-11-01

    We conducted a survey on nontuberculous mycobacteria (NTM) isolated in association with colonscopy at two hospitals. NTM was isolated from the fluid-phase of colonic contents in 17.6% of the specimens obtained at hospital A and in 46.3% at hospital B. The rate of isolation from the preexamination suction fluid was 9.5% and 43.3% at hospital A and B, respectively. Tap water samples from both hospitals were examined and proved to be free from contamination with NTM. The mycobacterial species isolated at hospital A were M. chelonae subsp. abscessus, M. chelonae subsp. chelonae, M. fortuitum, and M. gordonae. M. chelonae subsp. abscessus was the only mycobacterial species isolated at hospital B. M. avium complex was not isolated at either hospital. By an additional procedure to cleans and decontaminate the endoscopes by suction with Maskin ethanol solution, the incidence of isolation of NTM from the fluid-phase of colonic contents was significantly reduced. None of the patients from whom NTM was isolated exhibited positive signs of colonic NTM infection by the endoscopic examination and non had any underlying diseases which might induce immune suppression. We suspect that most of the NTM isolates have originated from the contaminated endoscope. In conclusion, when a colonscopic examination is carried out in suspicion of NTM disease in intestine, it is essential to reassess the possibility of mycobacterial contamination of the colonscopes and implement appropriate steps for cleansing and sterilization of them. PMID:8656587

  13. Environmental Nontuberculous Mycobacteria in the Hawaiian Islands

    PubMed Central

    Epperson, L. Elaine; Reynolds, Paul R.; Smith, Terry; Iakhiaeva, Elena; Bankowski, Matthew J.; Wallace, Richard J.; Chan, Edward D.; Falkinham, Joseph O.; Strong, Michael

    2016-01-01

    Lung disease caused by nontuberculous mycobacteria (NTM) is an emerging infectious disease of global significance. Epidemiologic studies have shown the Hawaiian Islands have the highest prevalence of NTM lung infections in the United States. However, potential environmental reservoirs and species diversity have not been characterized. In this cross-sectional study, we describe molecular and phylogenetic comparisons of NTM isolated from 172 household plumbing biofilms and soil samples from 62 non-patient households and 15 respiratory specimens. Although non-uniform geographic sampling and availability of patient information were limitations, Mycobacterium chimaera was found to be the dominant species in both environmental and respiratory specimens. In contrast to previous studies from the continental U.S., no Mycobacterium avium was identified. Mycobacterium intracellulare was found only in respiratory specimens and a soil sample. We conclude that Hawai’i’s household water sources contain a unique composition of Mycobacterium avium complex (MAC), increasing our appreciation of NTM organisms of pulmonary importance in tropical environments. PMID:27780201

  14. Epidemiology of Nontuberculous Mycobacteria in French Polynesia

    PubMed Central

    Phelippeau, Michael; Aboubaker Osman, Djaltou; Musso, Didier

    2015-01-01

    As few data are available in the Pacific countries and territories of the Oceania region regarding nontuberculous mycobacteria, we retrospectively identified 87 such isolates from French Polynesia from 2008 to 2013 by hybridization using DNA-strip, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and partial rpoB gene sequencing. Partial rpoB gene sequencing classified 42/87 (48.3%) isolates in the Mycobacterium fortuitum complex, 28 (32.2%) in the Mycobacterium abscessus complex, 8 (9.2%) in the Mycobacterium mucogenicum complex, and 5 (5.7%) in the Mycobacterium avium complex. Two isolates were identified as Mycobacterium acapulcensis and Mycobacterium cosmeticum by partial 16S rRNA gene sequencing. One isolate, unidentified by MALDI-TOF MS and yielding less than 92% and 96% sequence similarity with rpoB and hsp65 reference sequences, respectively, was regarded as a potentially new species. Samples from three patients exhibiting ≥2 Mycobacterium porcinum isolates and from one patient with emphysema and a lung abscess exhibiting 2 Mycobacterium senegalense isolates fulfilled the American Thoracic Society microbiological criteria for nontuberculous mycobacterial lung infection. Remote geographic areas, such as French Polynesia, are potential sources for the discovery of new mycobacterial species. PMID:26400787

  15. Taiwan: growing, growing, gone.

    PubMed

    Hanson, R

    1979-10-01

    Accommodation between Taiwan and the People's Republic of China may not be inconceivable as trade contacts (though officially disallowed) grow. Because of Taiwan's well-established success and the pressing need in China to industrialize, it appears, however, that such an accommodation will occur only after China becomes more like Taiwan. Taiwan owes its success, first, to land reform and then, in the 1960s, to steady industrialization. Besides broad controls over money supply and capital designed to ward off inflationary pressures when needed, and the grand outlines for development, another factor in the island's economic success is that the government has interfered little with private enterprise. The economy has an underpinning of small to medium size businesses. There are more than 10,000 trading companies. This diverse foundation has given the economy as a whole a flexible buffer on which more sophisticated industires can be formed. PMID:12278253

  16. Characterization of non-tuberculosis mycobacteria by neutron radiography.

    PubMed

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

    2013-07-01

    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

  17. Nontuberculous mycobacteria: Reports of clinical laboratory isolation in a three county area, North Carolina, 2006 -2010

    EPA Science Inventory

    Background: Laboratory reports of mycobacteria isolation and identification are created during the clinical diagnostic process to differentiate Mycobacterium tuberculosis from nontuberculous mycobacteria (NTM). NTM isolation rates are expected to exceed rates of true NTM infectio...

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

    EPA Science Inventory

    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...

  19. Mass Spectrometry Offers Insight into the Role of Ser/Thr/Tyr Phosphorylation in the Mycobacteria

    PubMed Central

    Calder, Bridget; Albeldas, Claudia; Blackburn, Jonathan M.; Soares, Nelson C.

    2016-01-01

    Phosphorylation is a post translational modification which can rapidly regulate biochemical pathways by altering protein function, and has been associated with pathogenicity in bacteria. Once engulfed by host macrophages, pathogenic bacteria are exposed to harsh conditions and must respond rapidly in order to survive. The causative agent of TB, Mycobacterium tuberculosis, is unusual amongst the bacteria because it can survive within the host macrophage for decades in a latent state, demonstrating a remarkable capacity to successfully evade the host immune response. This ability may be mediated in part by regulatory mechanisms such as ser/thr/tyr phosphorylation. Mass spectrometry-based proteomics has afforded us the capacity to identify hundreds of phosphorylation sites in the bacterial proteome, allowing for comparative phosphoproteomic studies in the mycobacteria. There remains an urgent need to validate the reported phosphosites, and to elucidate their biological function in the context of pathogenicity. However, given the sheer number of putative phosphorylation events in the mycobacterial proteome, and the technical difficulty of assigning biological function to a phosphorylation event, it will not be trivial to do so. There are currently six published phosphoproteomic investigations of a member of mycobacteria. Here, we combine the datasets from these studies in order to identify commonly detected phosphopeptides and phosphosites in order to present high confidence candidates for further validation. By applying modern mass spectrometry-based techniques to improve our understanding of phosphorylation and other PTMs in pathogenic bacteria, we may identify candidates for therapeutic intervention. PMID:26904014

  20. Concurrent Nontuberculous Mycobacteria Infection and High-Grade Anterior Mediastinal Extraskeletal Osteosarcoma (ESOS): Is There a Connection?

    PubMed

    Faz, Gabriel T; Eltorky, Mahmoud; Karnath, Bernard

    2016-01-01

    BACKGROUND Extraskeletal osteosarcomas (ESOS) of the mediastinum are extremely rare and may present with concurrent nontuberculous mycobacteria infection. CASE REPORT We present the second documented case of high-grade anterior mediastinal extraskeletal osteosarcoma in a 59-year-old man with a history of treated, latent tuberculosis (TB). Sputum samples grew Mycoplasma avium complex and Mycobacterium fortuitum. Imaging showed a right-sided 7.6 cm mass with compression of the main bronchus. Subsequent biopsy with vimentin staining established the diagnosis of ESOS. Due to the patient's rapidly declining performance status, he was not deemed a candidate for surgery or chemotherapy. He subsequently expired within one month of presentation. CONCLUSIONS We present a unique case of high-grade anterior mediastinum ESOS and a review of the literature regarding all documented cases of ESOS to date. We suggest there is a possible link between mediastinal masses and nontuberculous mycobacteria infection. PMID:27539718

  1. Effects of growth and tissue type on the kinetics of 13C and 15N incorporation in a rapidly growing ectotherm.

    PubMed

    Reich, Kimberly J; Bjorndal, Karen A; Martínez Del Rio, Carlos

    2008-04-01

    The use of stable isotopes to investigate animal diets, habitat use, and trophic level requires understanding the rate at which animals incorporate the 13C and 15N from their diets and the factors that determine the magnitude of the difference in isotopic composition between the animal's diet and that of its tissues. We determined the contribution of growth and catabolic turnover to the rate of 13C and 15N incorporation into several tissues that can be sampled non-invasively (skin, scute, whole blood, red blood cells, and plasma solutes) in two age classes of a rapidly growing ectotherm (loggerhead turtles, Caretta caretta). We found significant differences in C and N incorporation rates and isotopic discrimination factors (Delta 13C = delta 13Ctissues - delta 13Cdiet and Delta 15N = delta 15Ntissues - delta 15Ndiet) among tissues and between age classes. Growth explained from 26 to 100% of the total rate of incorporation in hatchling turtles and from 15 to 52% of the total rate of incorporation in juvenile turtles. Because growth contributed significantly to the rate of isotopic incorporation, variation in rates among tissues was lower than reported in previous studies. The contribution of growth can homogenize the rate of isotopic incorporation and limit the application of stable isotopes to identify dietary changes at contrasting time scales and to determine the timing of diet shifts. The isotopic discrimination factor of nitrogen ranged from -0.64 to 1.77 per thousand in the turtles' tissues. These values are lower than the commonly assumed average 3.4 per thousand discrimination factors reported for whole body and muscle isotopic analyses. The increasing reliance on non-invasive and non-destructive sampling in animal isotopic ecology requires that we recognize and understand why different tissues differ in isotopic discrimination factors.

  2. Conversion of NO2 to NO by reduced coenzyme F420 protects mycobacteria from nitrosative damage

    PubMed Central

    Purwantini, Endang; Mukhopadhyay, Biswarup

    2009-01-01

    In mycobacteria, F420, a deazaflavin derivative, acts as a hydride transfer coenzyme for an F420-specific glucose-6-phosphate dehydrogenase (Fgd). Physiologically relevant reactions in the mycobacteria that use Fgd-generated reduced F420 (F420H2) are unknown. In this work, F420H2 was found to be oxidized by NO only in the presence of oxygen. Further analysis demonstrated that NO2, produced from NO and O2, was the oxidant. UV-visible spectroscopic and NO-sensor-based analyses proved that F420H2 reduced NO2 to NO. This reaction could serve as a defense system for Mycobacterium tuberculosis, which is more sensitive to NO2 than NO under aerobic conditions. Activated macrophages produce NO, which in acidified phagosomes is converted to NO2. Hence, by converting NO2 back to NO with F420H2, M. tuberculosis could decrease the effectiveness of antibacterial action of macrophages; such defense would correspond to active tuberculosis conditions where the bacterium grows aerobically. This hypothesis was consistent with the observation that a mutant strain of Mycobacterium smegmatis, a nonpathogenic relative of M. tuberculosis, which either did not produce or could not reduce F420, was ≈4-fold more sensitive to NO2 than the wild-type strain. The phenomenon is reminiscent of the anticancer activity of γ-tocopherol, which reduces NO2 to NO and protects human cells from NO2-induced carcinogenesis. PMID:19325122

  3. The ESX-5 System of Pathogenic Mycobacteria Is Involved In Capsule Integrity and Virulence through Its Substrate PPE10

    PubMed Central

    Ates, Louis S.; van der Woude, Aniek D.; Bestebroer, Jovanka; van Stempvoort, Gunny; Musters, René J. P.; Garcia-Vallejo, Juan J.; Picavet, Daisy I.; van de Weerd, Robert; Maletta, Massimiliano; Kuijl, Coenraad P.; van der Wel, Nicole N.; Bitter, Wilbert

    2016-01-01

    Mycobacteria produce a capsule layer, which consists of glycan-like polysaccharides and a number of specific proteins. In this study, we show that, in slow-growing mycobacteria, the type VII secretion system ESX-5 plays a major role in the integrity and stability of the capsule. We have identified PPE10 as the ESX-5 substrate responsible for this effect. Mutants in esx-5 and ppe10 both have impaired capsule integrity as well as reduced surface hydrophobicity. Electron microscopy, immunoblot and flow cytometry analyses demonstrated reduced amounts of surface localized proteins and glycolipids, and morphological differences in the capsular layer. Since capsular proteins secreted by the ESX-1 system are important virulence factors, we tested the effect of the mutations that cause capsular defects on virulence mechanisms. Both esx-5 and ppe10 mutants of Mycobacterium marinum were shown to be impaired in ESX-1-dependent hemolysis. In agreement with this, the ppe10 and esx5 mutants showed reduced recruitment of ubiquitin in early macrophage infection and intermediate attenuation in zebrafish embryos. These results provide a pivotal role for the ESX-5 secretion system and its substrate PPE10, in the capsular integrity of pathogenic mycobacteria. These findings open up new roads for research on the mycobacterial capsule and its role in virulence and immune modulation. PMID:27280885

  4. Phosphorylation of the Peptidoglycan Synthase PonA1 Governs the Rate of Polar Elongation in Mycobacteria

    PubMed Central

    Kieser, Karen J.; Baer, Christina E.; Barczak, Amy K.; Meniche, Xavier; Chao, Michael C.; Rego, E. Hesper; Sassetti, Christopher M.; Fortune, Sarah M.; Rubin, Eric J.

    2015-01-01

    Cell growth and division are required for the progression of bacterial infections. Most rod-shaped bacteria grow by inserting new cell wall along their mid-section. However, mycobacteria, including the human pathogen Mycobacterium tuberculosis, produce new cell wall material at their poles. How mycobacteria control this different mode of growth is incompletely understood. Here we find that PonA1, a penicillin binding protein (PBP) capable of transglycosylation and transpeptidation of cell wall peptidoglycan (PG), is a major governor of polar growth in mycobacteria. PonA1 is required for growth of Mycobacterium smegmatis and is critical for M. tuberculosis during infection. In both cases, PonA1’s catalytic activities are both required for normal cell length, though loss of transglycosylase activity has a more pronounced effect than transpeptidation. Mutations that alter the amount or the activity of PonA1 result in abnormal formation of cell poles and changes in cell length. Moreover, altered PonA1 activity results in dramatic differences in antibiotic susceptibility, suggesting that a balance between the two enzymatic activities of PonA1 is critical for survival. We also find that phosphorylation of a cytoplasmic region of PonA1 is required for normal activity. Mutations in a critical phosphorylated residue affect transglycosylase activity and result in abnormal rates of cell elongation. Together, our data indicate that PonA1 is a central determinant of polar growth in mycobacteria, and its governance of cell elongation is required for robust cell fitness during both host-induced and antibiotic stress. PMID:26114871

  5. Draft Genome Sequences of Five Rapidly Growing Mycobacterium Species, M. thermoresistibile, M. fortuitum subsp. acetamidolyticum, M. canariasense, M. brisbanense, and M. novocastrense

    PubMed Central

    Katahira, Katsuyuki; Ogura, Yoshitoshi; Gotoh, Yasuhiro

    2016-01-01

    We report here the draft genome sequences of five rapidly growing Mycobacterium (RGM) species potentially pathogenic to humans, M. thermoresistibile, M. fortuitum subsp. acetamidolyticum, M. canariasense, M. brisbanense, and M. novocastrense. As the clinical importance of RGMs is increasingly being recognized worldwide, these sequences would contribute to further advances in RGM research. PMID:27231354

  6. Innate immune sensing of nucleic acids from mycobacteria.

    PubMed

    Yamashiro, Lívia Harumi; Oliveira, Sérgio Costa; Báfica, André

    2014-12-01

    Endosomal and cytosolic receptors engage recognition of mycobacterial-derived nucleic acids (MyNAs). In contrast, virulent mycobacteria may utilize nucleic acid recognition pathways to escape the host immune system. This short review will summarize the mechanisms by which MyNAs are sensed and how they influence host protective responses.

  7. Prospecting Environmental Mycobacteria: combined molecular approaches reveal unprecedented diversity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Environmental mycobacteria (EM) include species commonly found in a variety of terrestrial and aquatic environments and encompass animal and human pathogens in addition to saprophytes. Approximately 150 EM species can be separated into fast and slow growers based on sequence and copy number differen...

  8. The water environment as a source of potentially pathogenic mycobacteria.

    PubMed

    Makovcova, Jitka; Slany, Michal; Babak, Vladimir; Slana, Iva; Kralik, Petr

    2014-06-01

    Nontuberculous mycobacteria (NTM) are ubiquitous organisms of a wide variety of environmental reservoirs, including natural and municipal water, soil, aerosols, protozoans, animals and humans. Several of these species are potential pathogens which affect human health. The aim of this study was to determine the occurrence of NTM in the water environment. Samples were taken from 13 water-related facilities including fish ponds, storage ponds, drinking water reservoirs and an experimental recirculation system. Altogether, 396 samples of water, sediment and aquatic plants were collected and analysed. All samples were examined using conventional culture methods. Suspected microbial isolates were subjected to polymerase chain reaction analysis and identified using partial sequence analysis of the 16S rDNA gene. The culture revealed 94/396 samples (23.7%) that contained mycobacteria. Among known NTM we identified potentially pathogenic mycobacteria isolated from the fresh water environment for the first time: Mycobacterium asiaticum, M. chimaera, M. interjectum, M. kumamotonense, M. lentiflavum, M. montefiorense, M. nebraskense, M. paraffinicum and M. simiae. Epidemiologic studies suggest that the natural water environment is the principal source of human exposure. Our results indicate that besides the well-known potentially pathogenic mycobacteria it is important to observe occurrence, proliferation and persistence of newly discovered mycobacterial species.

  9. CarD: a new RNA polymerase modulator in mycobacteria.

    PubMed

    Stallings, Christina L; Glickman, Michael S

    2011-01-01

    Mycobacteria CarD is an essential RNAP binding protein that regulates many transcripts including rRNA. This article will review our present state of knowledge regarding CarD and compare the known functions of CarD with other RNAP binding proteins in E. coli, emphasizing how this information can guide future investigations.

  10. The water environment as a source of potentially pathogenic mycobacteria.

    PubMed

    Makovcova, Jitka; Slany, Michal; Babak, Vladimir; Slana, Iva; Kralik, Petr

    2014-06-01

    Nontuberculous mycobacteria (NTM) are ubiquitous organisms of a wide variety of environmental reservoirs, including natural and municipal water, soil, aerosols, protozoans, animals and humans. Several of these species are potential pathogens which affect human health. The aim of this study was to determine the occurrence of NTM in the water environment. Samples were taken from 13 water-related facilities including fish ponds, storage ponds, drinking water reservoirs and an experimental recirculation system. Altogether, 396 samples of water, sediment and aquatic plants were collected and analysed. All samples were examined using conventional culture methods. Suspected microbial isolates were subjected to polymerase chain reaction analysis and identified using partial sequence analysis of the 16S rDNA gene. The culture revealed 94/396 samples (23.7%) that contained mycobacteria. Among known NTM we identified potentially pathogenic mycobacteria isolated from the fresh water environment for the first time: Mycobacterium asiaticum, M. chimaera, M. interjectum, M. kumamotonense, M. lentiflavum, M. montefiorense, M. nebraskense, M. paraffinicum and M. simiae. Epidemiologic studies suggest that the natural water environment is the principal source of human exposure. Our results indicate that besides the well-known potentially pathogenic mycobacteria it is important to observe occurrence, proliferation and persistence of newly discovered mycobacterial species. PMID:24937219

  11. [Inactivation of Mycobacteria mucogenicum in drinking water: chlorine resistance and mechanism analysis].

    PubMed

    Zheng, Qi; Chen, Chao; Zhang, Xiao-Jian; Lu, Pin-Pin; Liu, Yuan-Yuan; Chen, Yu-Qiao

    2013-02-01

    In recent years, chlorine-resistant bacteria were detected in drinking water distribution systems which threatened the drinking water safety. Our group detected one strain named Mycobacteria mucogenicum from the drinking water distribution system of a city in south China. This paper studied chlorine resistance and mechanism of Mycobacteria mucogenicum. Inactivation experiments of one strain Mycobacteria mucogenicum were conducted with free chlorine, monochloramind and chlorine dioxide. The CT values of 99.9% inactivation by free chlorine, monochloramine and chlorine dioxide were detected as (76.25 +/- 47.55)mg.min.L-1, (1396 +/-382)mg.min.L-1, (13.5 +/- 4.9) mg.min L-1. Using transmission electronmicroscopy (TEM) observed the inactivation process of Mycobacteria mucogenicum. The bacteria surface hydrophobic of Mycobacteria mucogenicum was 37.2%. Mycobacteria mucogenicum has a higher hydrophobicity than other bacteria which prevented the diffusion of chlorine into cells. Mycobacteria mucogenicum is more resistant to chorine than other bacteria.

  12. Evaluation of practical chromatographic procedures for identification of clinical isolates of mycobacteria.

    PubMed Central

    Luquin, M; Ausina, V; López Calahorra, F; Belda, F; García Barceló, M; Celma, C; Prats, G

    1991-01-01

    After experimental conditions were established, 366 strains of mycobacteria belonging to 23 different species were studied for fatty acids, secondary alcohols, and mycolic acid cleavage products by capillary gas-liquid chromatography. Additionally, the mycolic acid pattern was studied by thin-layer chromatography. Capillary gas-liquid chromatography allowed direct identification of the following Mycobacterium spp.: M. kansasii, M. marinum, M. szulgai, M. xenopi, M. malmoense, and M. gordonae. The patterns of mycolic acid methyl esters recorded for the test strains of M. chelonae and M. agri may be of value in the identification of these species. Moreover, the combined use of the two chromatographic techniques provided precise identification of the M. tuberculosis complex, M. simiae, M. fallax, M. triviale, and M. chelonae-like organisms. A minimal set of biochemical tests is usually required to obtain identification to the species level when chromatographic procedures alone are not sufficient. Under the reported experimental conditions, thin-layer chromatography and capillary gas-liquid chromatography are rapid and very useful techniques for the identification of mycobacteria. Images PMID:1993746

  13. Multiprimer PCR system for differential identification of mycobacteria in clinical samples.

    PubMed Central

    Del Portillo, P; Thomas, M C; Martínez, E; Marañón, C; Valladares, B; Patarroyo, M E; Carlos López, M

    1996-01-01

    A novel multiprimer PCR method with the potential to identify mycobacteria in clinical samples is presented. The assay relies on the simultaneous amplification of three bacterial DNA genomic fragments by using different sets of oligonucleotide primers. The first set of primers amplifies a 506-bp fragment from the gene for the 32-kDa antigen of Mycobacterium tuberculosis, which is present in most of the species belonging to the genus Mycobacterium. The second set of primers amplifies a 984-bp fragment from the IS6110 insertion sequence of the bacteria belonging to the M. tuberculosis complex. The third set of primers, derived from an M. tuberculosis species-specific sequence named MTP40, amplifies a 396-bp genomic fragment. Thus, while the multiprimer system would render three amplification fragments from the M. tuberculosis genome and two fragments from the Mycobacterium bovis genome, a unique amplification fragment would be obtained from nontuberculous mycobacteria. The results obtained, using reference mycobacterial strains and typed clinical isolates, show that the multiprimer PCR method may be a rapid, sensitive, and specific tool for the differential identification of various mycobacterial strains in a single-step assay. PMID:8789008

  14. Flood hazard and a rapidly growing capital in the floodplain: Social response on major 18th-century Danube floods in Pest (East-Budapest)

    NASA Astrophysics Data System (ADS)

    Kiss, Andrea

    2014-05-01

    Due to its floodplain location, Pest was especially prone to damages caused by great flood events. Before water regulation works, the greatest flood events, and the highest rate of destruction occurred during ice jam floods. Whereas in the first half of the 18th century Pest is restricted to the medieval downtown located on a higher terrain (Danube terrace), from the mid 18th century onwards the rapidly growing population established suburbs around the downtown in the lower-lying flood plain. Thus, while in the first half of the century floods were more dangerous for the harvest in the agricultural lands, in the second half of the century at the same place suburbs, urban areas with thousands of inhabitants were prone to the same danger. In the first half of the century at least three particularly large flood events, in 1712, 1732 and 1744, caused increasing problems in the close vicinity of the town (and its lands), the second half of the century - as part of a climatic anomaly (Maldá) famous of its weather extremes - was characterised by two extreme (in 1775 and 1799), at least two larger (1789 and 1795) and some more, medium-sized ice jam floods. While in terms of damaged houses the loss was only some dozens in the early part of the century, several hundreds of houses - actually, complete suburbs were erased by floods in 1775 and 1799. In the poster presentation a series of known damaging 18th-century floods, occurred at Pest, is presented, the short-term impacts (e.g. damages), and medium-, long-term administrative responses as well as related long-term landscape changes influenced by floods and flood protection are discussed. Another important aim of the poster is to present the main reasons why in the 18th century these great ice jam floods caused much greater damages (e.g. percentage of collapsed houses in suburbs) in Pest protected by dams than, for example, in the Buda suburbs with no dams, partly also located in high flood-risk areas, in the immediate

  15. Distribution of environmental mycobacteria in Karonga District, northern Malawi.

    PubMed

    Chilima, Benson Z; Clark, Ian M; Floyd, Sian; Fine, Paul E M; Hirsch, Penny R

    2006-04-01

    The genus Mycobacterium includes many species that are commonly found in the environment (in soil and water or associated with plants and animals), as well as species that are responsible for two major human diseases, tuberculosis (Mycobacterium tuberculosis) and leprosy (Mycobacterium leprae). The distribution of environmental mycobacteria was investigated in the context of a long-term study of leprosy, tuberculosis, Mycobacterium bovis BCG vaccination, and the responses of individuals to various mycobacterial antigens in Karonga District, northern Malawi, where epidemiological studies had indicated previously that people may be exposed to different mycobacterial species in the northern and southern parts of the district. A total of 148 soil samples and 24 water samples were collected from various locations and examined to determine the presence of mycobacteria. The detection method involved semiselective culturing and acid-fast staining, following decontamination of samples to enrich mycobacteria and reduce the numbers of other microorganisms, or PCR with primers specific for the mycobacterial 16S rRNA gene, using DNA extracted directly from soil and water samples. Mycobacteria were detected in the majority of the samples, and subsequent sequence analysis of PCR products amplified directly from soil DNA indicated that most of the products were related to known environmental mycobacteria. For both methods the rates of recovery were consistently higher for dry season samples than for wet season samples. All isolates cultured from soil appeared to be strains of Mycobacterium fortuitum. This study revealed a complex pattern for the environmental mycobacterial flora but identified no clear differences between the northern and southern parts of Karonga District.

  16. Understanding HIV-Mycobacteria synergism through comparative proteomics of intra-phagosomal mycobacteria during mono- and HIV co-infection

    PubMed Central

    Ganji, Rakesh; Dhali, Snigdha; Rizvi, Arshad; Rapole, Srikanth; Banerjee, Sharmistha

    2016-01-01

    Mycobacterium tuberculosis (Mtb) is the most common co-infection in HIV patients and a serious co-epidemic. Apart from increasing the risk of reactivation of latent tuberculosis (TB), HIV infection also permits opportunistic infection of environmental non-pathogenic mycobacteria. To gain insights into mycobacterial survival inside host macrophages and identify mycobacterial proteins or processes that influence HIV propagation during co-infection, we employed proteomics approach to identify differentially expressed intracellular mycobacterial proteins during mono- and HIV co-infection of human THP-1 derived macrophage cell lines. Of the 92 proteins identified, 30 proteins were upregulated during mycobacterial mono-infection and 40 proteins during HIV-mycobacteria co-infection. We observed down-regulation of toxin-antitoxin (TA) modules, up-regulation of cation transporters, Type VII (Esx) secretion systems, proteins involved in cell wall lipid or protein metabolism, glyoxalate pathway and branched chain amino-acid synthesis during co-infection. The bearings of these mycobacterial factors or processes on HIV propagation during co-infection, as inferred from the proteomics data, were validated using deletion mutants of mycobacteria. The analyses revealed mycobacterial factors that possibly via modulating the host environment, increased viral titers during co-infection. The study provides new leads for investigations towards hitherto unknown molecular mechanisms explaining HIV-mycobacteria synergism, helping address diagnostics and treatment challenges for effective co-epidemic management. PMID:26916387

  17. A system for the examination of tubercle bacilli and other mycobacteria.

    PubMed

    Marks, J

    1976-09-01

    Methods are described for the examination of mycobacteria cultured from clinical specimens. In the "screening" procedure used for new isolates tubercle bacilli are non-pigmented, do not grow at 25 degrees C and are sensitive to p-nitrobenzoic acid as well as normally to anti-tuberculosis drugs. Classification is extended when necessary by the use of four tests--temperature requirements, pigmentation, oxygen preference and Tween hydrolysis. These define 15 species or groups meeting the needs of clinical bacteriology. Drug-sensitivity tests are described which relate the end-points of titrations to the modal response of normal wild strains of M. tuberculosis. They are used not only as a guide to chemotherapy but also to support and amplify classification.

  18. The Heater Cooler as a Source of Infection from Nontuberculous Mycobacteria.

    PubMed

    Stammers, Alfred H; Riley, Jeffrey B

    2016-06-01

    Nosocomial infections acquired during the course of cardiac surgery and hospitalization can have devastating patient consequences. The source of these infections is often difficult to determine which complicates eradication efforts. Recently it has become apparent that the heater-cooler devices used in conjunction with cardiopulmonary bypass may become contaminated with bacteria that are normally found in hospital water sources. The culprit organisms are nontuberculous mycobacteria which coat the intrinsic surfaces found within the circuits of the heater-coolers. Aerosolization of the bacteria occurs during normal heater-cooler operation which can disperse the organisms throughout the operating room. The bacteria are slow-growing and may not present for months, or years, following exposure which makes epidemiological determination a challenge. The ensuing report summarizes a recent outbreak in these infections that have been reported both in Europe and the United States, along with efforts to reduce the risk for patient infection. PMID:27578894

  19. Innate immunity to mycobacteria: vitamin D and autophagy.

    PubMed

    Jo, Eun-Kyeong

    2010-08-01

    Autophagy is an ancient mechanism of protein degradation and a novel antimicrobial strategy. With respect to host defences against mycobacteria, autophagy plays a crucial role in antimycobacterial resistance, and contributes to immune surveillance of intracellular pathogens and vaccine efficacy. Vitamin D3 contributes to host immune responses against Mycobacterium tuberculosis through LL-37/hCAP-18, which is the only cathelicidin identified to date in humans. In this review, we discuss recent advances in our understanding of host immune strategies against mycobacteria, including vitamin D-mediated innate immunity and autophagy activation. This review also addresses our current understanding regarding the autophagy connection to principal innate machinery, such as ubiquitin- or inflammasome-involved pathways. Integrated dialog between autophagy and innate immunity may contribute to adequate host immune defences against mycobacterial infection.

  20. Free-living amoebae, a training field for macrophage resistance of mycobacteria.

    PubMed

    Salah, I B; Ghigo, E; Drancourt, M

    2009-10-01

    Mycobacterium species evolved from an environmental recent common ancestor by reductive evolution and lateral gene transfer. Strategies selected through evolution and developed by mycobacteria resulted in resistance to predation by environmental unicellular protists, including free-living amoebae. Indeed, mycobacteria are isolated from the same soil and water environments as are amoebae, and experimental models using Acanthamoeba spp. and Dictyostelium discoideum were exploited to analyse the mechanisms for intracellular survival. Most of these mechanisms have been further reproduced in macrophages for mycobacteria regarded as opportunistic and obligate pathogens. Amoebal cysts may protect intracellular mycobacteria against adverse conditions and may act as a vector for mycobacteria. The latter hypothesis warrants further environmental and clinical studies to better assess the role of free-living amoebae in the epidemiology of infections caused by mycobacteria.

  1. Studies on ribosomal RNA genes of mycobacteria including M. leprae.

    PubMed

    Katoch, V M; Shivannavar, C T; Datta, A K

    1989-01-01

    Information about specific genes specially of pathogenic mycobacteria could be used to unequivocally identify isolates of mycobacteria which are of clinical interest. Both eukaryotic and prokaryotic ribosomal RNA (rRNA) genes have been shown to comprise sequences which are conserved and others which are divergent. In the present study, rRNA genes from several cultivable mycobacteria including M. tuberculosis and armadillo derived M. leprae have been investigated. rRNA was isolated, made radioactive in vitro and then used to identify restriction fragments of DNA containing rRNA gene sequences. It was observed that restriction endonuclease patterns of rRNA genes are characteristic. By probing with homologous and heterologous rRNA probes, fragments hybridizing maximum with homologous probes could be identified and it appears that sequences flanking the rRNA genes are not identical. These fragments need to be further sequenced to identify the nucleotide sequences specific to rRNA gene cluster. It would also be necessary to analyse several isolates of each species including armadillo derived M. leprae before reaching any conclusions.

  2. An inducible expression system for high-level expression of recombinant proteins in slow growing mycobacteria.

    PubMed

    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. PMID:26021569

  3. Bioconversion of phytosterols to androstanes by mycobacteria growing on sugar cane mud.

    PubMed

    Pérez, C; Falero, A; Hung, B R; Tirado, S; Balcinde, Y

    2005-03-01

    Direct sterol conversion of sugar cane mud (residue) by Mycobacterium sp. was demonstrated to be possible technologically, thus avoiding sugar cane oil extraction and further processes of extraction and purification of phytosterols from this oil. Indeed, mycobacterial cells were able to convert phytosterols from sugar cane mud into 4-androstene-dione (AD) and 1,4 androsta-diene-3,17-dione (ADD). For the various concentrations assayed, concomitant higher yields for both androstanes were achieved at 20% (w/w) sugar cane mud in media. Furthermore, conversions were similar to those from other substrates, such as a mixture of phytosterols. The results suggest that the mycobacterial cell is able to easily access and bioconvert sugar cane mud phytosterols.

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

    PubMed

    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

  5. [Commemorative lecture of receiving Imamura Memorial Prize. I. Studies on bacteriological diagnostic methods for mycobacteria].

    PubMed

    Abe, C

    1994-08-01

    Two systems, radiometric BACTEC and biphasic MB-Check, based on liquid media proved to be significantly better than the egg-based solid media for the isolation of mycobacteria from clinical specimens. The difference in the rates of isolation of mycobacteria between two groups of media was more remarkable with smear-negative specimens. The time to the detection of the Mycobacterium tuberculosis complex with MB- Check was shorter than that with the 3% Ogawa egg method but longer than that with BACTEC. The polymerase chain reaction (PCR) using oligonucleotides based on the repetitive sequence (IS986) of M. tuberculosis as a primer and the Gen-Probe Amplified Mycobacterium Tuberculosis Direct Test (MTD), which combines an M. tuberculosis rRNA amplification method with the hybridization protection assay format, were evaluated for detection of M. tuberculosis in clinical samples. Although the sensitivities of the PCR and MTD appeared to be similar to that of culture with the MB-Check system, the two methods based on nucleic acid amplification should be very useful for rapid detection of M. tuberculosis infections without the long time required for culture of M. tuberculosis. Epidemiological studies with techniques which allow differentiation of strains within M. tuberculosis groups are important for limiting the dissemination of the disease. We analyzed six groups of small outbreaks of M. tuberculosis infections by restriction fragment length polymorphism (RFLP) analysis. Five showed identical fingerprints within each group, but one which as also suspected to have a common source of infection showed different banding patterns, emphasizing that RFLP analysis using IS986 as a probe is useful in epidemiological studies of tuberculosis.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. [Commemorative lecture of receiving Imamura Memorial Prize. I. Studies on bacteriological diagnostic methods for mycobacteria].

    PubMed

    Abe, C

    1994-08-01

    Two systems, radiometric BACTEC and biphasic MB-Check, based on liquid media proved to be significantly better than the egg-based solid media for the isolation of mycobacteria from clinical specimens. The difference in the rates of isolation of mycobacteria between two groups of media was more remarkable with smear-negative specimens. The time to the detection of the Mycobacterium tuberculosis complex with MB- Check was shorter than that with the 3% Ogawa egg method but longer than that with BACTEC. The polymerase chain reaction (PCR) using oligonucleotides based on the repetitive sequence (IS986) of M. tuberculosis as a primer and the Gen-Probe Amplified Mycobacterium Tuberculosis Direct Test (MTD), which combines an M. tuberculosis rRNA amplification method with the hybridization protection assay format, were evaluated for detection of M. tuberculosis in clinical samples. Although the sensitivities of the PCR and MTD appeared to be similar to that of culture with the MB-Check system, the two methods based on nucleic acid amplification should be very useful for rapid detection of M. tuberculosis infections without the long time required for culture of M. tuberculosis. Epidemiological studies with techniques which allow differentiation of strains within M. tuberculosis groups are important for limiting the dissemination of the disease. We analyzed six groups of small outbreaks of M. tuberculosis infections by restriction fragment length polymorphism (RFLP) analysis. Five showed identical fingerprints within each group, but one which as also suspected to have a common source of infection showed different banding patterns, emphasizing that RFLP analysis using IS986 as a probe is useful in epidemiological studies of tuberculosis.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7933779

  7. Isolation of Mycobacteria from clinical samples collected in the United States from 2004 to 2011

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Mycobacteria other than M. bovis (i.e. atypical mycobacteria) may interfere with current bovine tuberculosis diagnostic tests resulting in false positive test results. In populations with low prevalence of M. bovis (i.e., as detected within the United States), interference from atypical ...

  8. An IPTG Inducible Conditional Expression System for Mycobacteria

    PubMed Central

    Ravishankar, Sudha; Ambady, Anisha; Ramu, Haripriya; Mudugal, Naina Vinay; Tunduguru, Ragadeepthi; Anbarasu, Anand; Sharma, Umender K.; Sambandamurthy, Vasan K.; Ramaiah, Sudha

    2015-01-01

    Conditional expression strains serve as a valuable tool to study the essentiality and to establish the vulnerability of a target under investigation in a drug discovery program. While essentiality implies an absolute requirement of a target function, vulnerability provides valuable information on the extent to which a target function needs to be depleted to achieve bacterial growth inhibition followed by cell death. The critical feature of an ideal conditional expression system is its ability to tightly regulate gene expression to achieve the full spectrum spanning from a high level of expression in order to support growth and near zero level of expression to mimic conditions of gene knockout. A number of bacterial conditional expression systems have been reported for use in mycobacteria. The utility of an isopropylthiogalactoside (IPTG) inducible system in mycobacteria has been reported for protein overexpression and anti-sense gene expression from a replicating multi-copy plasmid. Herein, we report the development of a versatile set of non-replicating IPTG inducible vectors for mycobacteria which can be used for generation of conditional expression strains through homologous recombination. The role of a single lac operator versus a double lac operator to regulate gene expression was evaluated by monitoring the expression levels of β-galactosidase in Mycobacterium smegmatis. These studies indicated a significant level of leaky expression from the vector with a single lac operator but none from the vector with double lac operator. The significance of the double lac operator vector for target validation was established by monitoring the growth kinetics of an inhA, a rpoB and a ftsZ conditional expression strain grown in the presence of different concentrations of IPTG. The utility of this inducible system in identifying target specific inhibitors was established by screening a focussed library of small molecules using an inhA and a rpoB conditional expression

  9. Quantitative proteomic analysis of drug-induced changes in mycobacteria.

    PubMed

    Hughes, Minerva A; Silva, Jeffrey C; Geromanos, Scott J; Townsend, Craig A

    2006-01-01

    A new approach for qualitative and quantitative proteomic analysis using capillary liquid chromatography and mass spectrometry to study the protein expression response in mycobacteria following isoniazid treatment is discussed. In keeping with known effects on the fatty acid synthase II pathway, proteins encoded by the kas operon (AcpM, KasA, KasB, Accd6) were significantly overexpressed, as were those involved in iron metabolism and cell division suggesting a complex interplay of metabolic events leading to cell death. PMID:16396495

  10. Regulated Expression Systems for Mycobacteria and Their Applications

    PubMed Central

    Schnappinger, Dirk; Ehrt, Sabine

    2014-01-01

    For bacterial model organisms like Escherichia coli and Bacillus subtilis genetic tools to experimentally manipulate the activity of individual genes existed for decades. But for genetically less tractable yet medically important bacteria such as M. tuberculosis such tools have rarely been available. More recently several groups developed genetic switches that function efficiently in M. tuberculosis and other mycobacteria. Together these systems utilize six different transcription factors, eight different regulated promoters, and three different regulatory principles. Here we describe their design features, review their main applications, and discuss advantages and disadvantages of regulating transcription, translation, or protein stability for controlling gene activities in bacteria. PMID:25485177

  11. [Breeding and management of mycobacteria-free guinea pigs (author's transl)].

    PubMed

    Kazda, J

    1976-08-01

    A number of mycobacterial species are detectable under conventional holding condition of guinea pigs. These mycobacteria originating in drinking water and litter caused cross reactions in the Jones-Mote hypersensitivity test. Using suitable precautions it was possible to breed and hold the animals mycobacteria-free. The precautions depend mainly in alteration of the wire mesh floor in cages to avoide the contact of the animals with the litter, in cleaning and desinfection of water bottles, in using of heated water and food and in the prevention of mycobacterial contamination from the staff. The control examination on mycobacteria without treating is given in details. Cases are refered in which a oral rece ption of mycobacteria can alter the immune response. The modification of guinea pigs management to the mycobacteria-free ones is possible in a short time and with minimal cost.

  12. Crystal growing

    NASA Technical Reports Server (NTRS)

    Neville, J. P.

    1990-01-01

    One objective is to demonstrate the way crystals grow and how they affect the behavior of material. Another objective is to compare the growth of crystals in metals and nonmetals. The procedures, which involve a supersaturated solution of a salt that will separate into crystals on cooling and the pouring off of an eutectic solution to expose the crystals formed by a solid solution when an alloy of two metals forms a solid and eutectic solution on cooling, are described.

  13. Development of an in vitro Assay, Based on the BioFilm Ring Test®, for Rapid Profiling of Biofilm-Growing Bacteria

    PubMed Central

    Di Domenico, Enea G.; Toma, Luigi; Provot, Christian; Ascenzioni, Fiorentina; Sperduti, Isabella; Prignano, Grazia; Gallo, Maria T.; Pimpinelli, Fulvia; Bordignon, Valentina; Bernardi, Thierry; Ensoli, Fabrizio

    2016-01-01

    Microbial biofilm represents a major virulence factor associated with chronic and recurrent infections. Pathogenic bacteria embedded in biofilms are highly resistant to environmental and chemical agents, including antibiotics and therefore difficult to eradicate. Thus, reliable tests to assess biofilm formation by bacterial strains as well as the impact of chemicals or antibiotics on biofilm formation represent desirable tools for a most effective therapeutic management and microbiological risk control. Current methods to evaluate biofilm formation are usually time-consuming, costly, and hardly applicable in the clinical setting. The aim of the present study was to develop and assess a simple and reliable in vitro procedure for the characterization of biofilm-producing bacterial strains for future clinical applications based on the BioFilm Ring Test® (BRT) technology. The procedure developed for clinical testing (cBRT) can provide an accurate and timely (5 h) measurement of biofilm formation for the most common pathogenic bacteria seen in clinical practice. The results gathered by the cBRT assay were in agreement with the traditional crystal violet (CV) staining test, according to the κ coefficient test (κ = 0.623). However, the cBRT assay showed higher levels of specificity (92.2%) and accuracy (88.1%) as compared to CV. The results indicate that this procedure offers an easy, rapid and robust assay to test microbial biofilm and a promising tool for clinical microbiology. PMID:27708625

  14. Effect of disinfectant, water age, and pipe material on occurrence and persistence of Legionella, mycobacteria, Pseudomonas aeruginosa, and two amoebas.

    PubMed

    Wang, Hong; Masters, Sheldon; Hong, Yanjuan; Stallings, Jonathan; Falkinham, Joseph O; Edwards, Marc A; Pruden, Amy

    2012-11-01

    Opportunistic pathogens represent a unique challenge because they establish and grow within drinking water systems, yet the factors stimulating their proliferation are largely unknown. The purpose of this study was to examine the influence of pipe materials, disinfectant type, and water age on occurrence and persistence of three opportunistic pathogens (Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa), broader genera (Legionella and mycobacteria), and two amoeba hosts (Acanthamoeba spp. and Hartmanella vermiformis). Triplicate simulated distribution systems (SDSs) compared iron, cement, and PVC pipe materials fed either chlorinated or chloraminated tap water and were sampled at water ages ranging from 1 day to 5.7 days. Quantitative polymerase chain reaction quantified gene copies of target microorganisms in both biofilm and bulk water. Legionella, mycobacteria, P. aeruginosa, and both amoebas naturally colonized the six SDSs, but L. pneumophila and M. avium were not detected. Disinfectant type and dose was observed to have the strongest influence on the microbiota. Disinfectant decay was noted with water age, particularly in chloraminated SDSs (due to nitrification), generally resulting in increased microbial detection frequencies and densities with water age. The influence of pipe material became apparent at water ages corresponding to low disinfectant residual. Each target microbe appeared to display a distinct response to disinfectant type, pipe materials, water age, and their interactions. Differences between the first and the second samplings (e.g., appearance of Legionella, reduction in P. aeruginosa and Acanthamoeba) suggest a temporally dynamic drinking water microbial community.

  15. Effect of disinfectant, water age, and pipe material on occurrence and persistence of Legionella, mycobacteria, Pseudomonas aeruginosa, and two amoebas.

    PubMed

    Wang, Hong; Masters, Sheldon; Hong, Yanjuan; Stallings, Jonathan; Falkinham, Joseph O; Edwards, Marc A; Pruden, Amy

    2012-11-01

    Opportunistic pathogens represent a unique challenge because they establish and grow within drinking water systems, yet the factors stimulating their proliferation are largely unknown. The purpose of this study was to examine the influence of pipe materials, disinfectant type, and water age on occurrence and persistence of three opportunistic pathogens (Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa), broader genera (Legionella and mycobacteria), and two amoeba hosts (Acanthamoeba spp. and Hartmanella vermiformis). Triplicate simulated distribution systems (SDSs) compared iron, cement, and PVC pipe materials fed either chlorinated or chloraminated tap water and were sampled at water ages ranging from 1 day to 5.7 days. Quantitative polymerase chain reaction quantified gene copies of target microorganisms in both biofilm and bulk water. Legionella, mycobacteria, P. aeruginosa, and both amoebas naturally colonized the six SDSs, but L. pneumophila and M. avium were not detected. Disinfectant type and dose was observed to have the strongest influence on the microbiota. Disinfectant decay was noted with water age, particularly in chloraminated SDSs (due to nitrification), generally resulting in increased microbial detection frequencies and densities with water age. The influence of pipe material became apparent at water ages corresponding to low disinfectant residual. Each target microbe appeared to display a distinct response to disinfectant type, pipe materials, water age, and their interactions. Differences between the first and the second samplings (e.g., appearance of Legionella, reduction in P. aeruginosa and Acanthamoeba) suggest a temporally dynamic drinking water microbial community. PMID:23046164

  16. Definition of the first mannosylation step in phosphatidylinositol mannoside synthesis. PimA is essential for growth of mycobacteria.

    PubMed

    Korduláková, Jana; Gilleron, Martine; Mikusova, Katarína; Puzo, Germain; Brennan, Patrick J; Gicquel, Brigitte; Jackson, Mary

    2002-08-30

    We examined the function of the pimA (Rv2610c) gene, located in the vicinity of the phosphatidylinositol synthase gene in the genomes of Mycobacterium tuberculosis and Mycobacterium smegmatis, which encodes a putative mannosyltransferase involved in the early steps of phosphatidylinositol mannoside synthesis. A cell-free assay was developed in which membranes from M. smegmatis overexpressing the pimA gene incorporate mannose from GDP-[(14)C]Man into di- and tri-acylated phosphatidylinositol mono-mannosides. Moreover, crude extracts from Escherichia coli producing a recombinant PimA protein synthesized diacylated phosphatidylinositol mono-mannoside from GDP-[(14)C]Man and bovine phosphatidylinositol. To determine whether PimA is an essential enzyme of mycobacteria, we constructed a pimA conditional mutant of M. smegmatis. The ability of this mutant to synthesize the PimA mannosyltransferase was dependent on the presence of a functional copy of the pimA gene carried on a temperature-sensitive rescue plasmid. We demonstrate here that the pimA mutant is unable to grow at the higher temperature at which the rescue plasmid is lost. Thus, the synthesis of phosphatidylinositol mono-mannosides and derived higher phosphatidylinositol mannosides in M. smegmatis appears to be dependent on PimA and essential for growth. This work provides the first direct evidence of the essentiality of phosphatidylinositol mannosides for the growth of mycobacteria.

  17. Compartmental analysis of roots in intact rapidly-growing Spergularia marina and Lactuca sativa: partial characterization of the symplasms functional in the radial transport of Na/sup +/ and K/sup +/

    SciTech Connect

    Lazof, D.B.

    1987-01-01

    Techniques of compartmental analysis were adapted to the study of intact roots of rapidly-growing Spergularia marine and Lactuca sativa. Using large numbers of plants short time-courses of uptake and chase, /sup 42/K/sup +/ and /sup 22/Na/sup +/ transport could be resolved, even during a chase following a brief 10 minute labeling period. The use of intact plant systems allowed distinction of that portion of the isotope flux into the root, associated with the ion-conducting symplasms. A small compartment, which rapidly (t/sub .5/ < 1 min) exchanges with the external medium was implicated in the radial transport of N/sup +/, accounting for the observed obtention of linear translocation rates within minutes of transferring to labeled solution. The ion contents of this compartment varied in proportion to the external ion concentration. When K/sup +/ was at a high external concentration, labeled K/sup +/ exchanged into this same symplasm, but chasing a short pulse indicated that K/sup +/ transport to the xylem was not through a rapidly-exchanging compartment. At physiological concentrations of K/sup +/ the evidence indicated that transport of K/sup +/ across the root proceeded through a compartment which was not exchanging rapidly with the external medium. The rise to a linear rate of isotope translocation was gradual and translocation during a chase, following a brief pulse,was prolonged, indicating that this compartment retained its specific activity for a considerable period.

  18. Cooccurrence of free-living amoebae and nontuberculous Mycobacteria in hospital water networks, and preferential growth of Mycobacterium avium in Acanthamoeba lenticulata.

    PubMed

    Ovrutsky, Alida R; Chan, Edward D; Kartalija, Marinka; Bai, Xiyuan; Jackson, Mary; Gibbs, Sara; Falkinham, Joseph O; Iseman, Michael D; Reynolds, Paul R; McDonnell, Gerald; Thomas, Vincent

    2013-05-01

    The incidence of lung and other diseases due to nontuberculous mycobacteria (NTM) is increasing. NTM sources include potable water, especially in households where NTM populate pipes, taps, and showerheads. NTM share habitats with free-living amoebae (FLA) and can grow in FLA as parasites or as endosymbionts. FLA containing NTM may form cysts that protect mycobacteria from disinfectants and antibiotics. We first assessed the presence of FLA and NTM in water and biofilm samples collected from a hospital, confirming the high prevalence of NTM and FLA in potable water systems, particularly in biofilms. Acanthamoeba spp. (genotype T4) were mainly recovered (8/17), followed by Hartmannella vermiformis (7/17) as well as one isolate closely related to the genus Flamella and one isolate only distantly related to previously described species. Concerning mycobacteria, Mycobacterium gordonae was the most frequently found isolate (9/17), followed by Mycobacterium peregrinum (4/17), Mycobacterium chelonae (2/17), Mycobacterium mucogenicum (1/17), and Mycobacterium avium (1/17). The propensity of Mycobacterium avium hospital isolate H87 and M. avium collection strain 104 to survive and replicate within various FLA was also evaluated, demonstrating survival of both strains in all amoebal species tested but high replication rates only in Acanthamoeba lenticulata. As A. lenticulata was frequently recovered from environmental samples, including drinking water samples, these results could have important consequences for the ecology of M. avium in drinking water networks and the epidemiology of disease due to this species.

  19. Specific Proteins in Nontuberculous Mycobacteria: New Potential Tools

    PubMed Central

    Orduña, Patricia; Castillo-Rodal, Antonia I.; Mercado, Martha E.; Ponce de León, Samuel; López-Vidal, Yolanda

    2015-01-01

    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. PMID:26106621

  20. Experimental selection of long-term intracellular mycobacteria.

    PubMed

    Vázquez, Cristina L; Lerner, Thomas R; Kasmapour, Bahram; Pei, Gang; Gronow, Achim; Bianco, Maria V; Blanco, Federico C; Bleck, Christopher K E; Geffers, Robert; Bigi, Fabiana; Abraham, Wolf-Rainer; Gutierrez, Maximiliano G

    2014-09-01

    Some intracellular bacteria are known to cause long-term infections that last decades without compromising the viability of the host. Although of critical importance, the adaptations that intracellular bacteria undergo during this long process of residence in a host cell environment remain obscure. Here, we report a novel experimental approach to study the adaptations of mycobacteria imposed by a long-term intracellular lifestyle. Selected Mycobacterium bovis BCG through continuous culture in macrophages underwent an adaptation process leading to impaired phenolic glycolipids (PGL) synthesis, improved usage of glucose as a carbon source and accumulation of neutral lipids. These changes correlated with increased survival of mycobacteria in macrophages and mice during re-infection and also with the specific expression of stress- and survival-related genes. Our findings identify bacterial traits implicated in the establishment of long-term cellular infections and represent a tool for understanding the physiological states and the environment that bacteria face living in fluctuating intracellular environments. PMID:24779357

  1. Experimental selection of long-term intracellular mycobacteria

    PubMed Central

    Vázquez, Cristina L; Lerner, Thomas R; Kasmapour, Bahram; Pei, Gang; Gronow, Achim; Bianco, Maria V; Blanco, Federico C; Bleck, Christopher K E; Geffers, Robert; Bigi, Fabiana; Abraham, Wolf-Rainer; Gutierrez, Maximiliano G

    2014-01-01

    Some intracellular bacteria are known to cause long-term infections that last decades without compromising the viability of the host. Although of critical importance, the adaptations that intracellular bacteria undergo during this long process of residence in a host cell environment remain obscure. Here, we report a novel experimental approach to study the adaptations of mycobacteria imposed by a long-term intracellular lifestyle. Selected Mycobacterium bovis BCG through continuous culture in macrophages underwent an adaptation process leading to impaired phenolic glycolipids (PGL) synthesis, improved usage of glucose as a carbon source and accumulation of neutral lipids. These changes correlated with increased survival of mycobacteria in macrophages and mice during re-infection and also with the specific expression of stress- and survival-related genes. Our findings identify bacterial traits implicated in the establishment of long-term cellular infections and represent a tool for understanding the physiological states and the environment that bacteria face living in fluctuating intracellular environments. PMID:24779357

  2. Pupylation-dependent and -independent proteasomal degradation in mycobacteria.

    PubMed

    Imkamp, Frank; Ziemski, Michal; Weber-Ban, Eilika

    2015-08-01

    Bacteria make use of compartmentalizing protease complexes, similar in architecture but not homologous to the eukaryotic proteasome, for the selective and processive removal of proteins. Mycobacteria as members of the actinobacteria harbor proteasomes in addition to the canonical bacterial degradation complexes. Mycobacterial proteasomal degradation, although not essential during normal growth, becomes critical for survival under particular environmental conditions, like, for example, during persistence of the pathogenic Mycobacterium tuberculosis in host macrophages or of environmental mycobacteria under starvation. Recruitment of protein substrates for proteasomal degradation is usually mediated by pupylation, the post-translational modification of lysine side chains with the prokaryotic ubiquitin-like protein Pup. This substrate recruitment strategy is functionally reminiscent of ubiquitination in eukaryotes, but is the result of convergent evolution, relying on chemically and structurally distinct enzymes. Pupylated substrates are recognized by the ATP-dependent proteasomal regulator Mpa that associates with the 20S proteasome core. A pupylation-independent proteasome degradation pathway has recently been discovered that is mediated by the ATP-independent bacterial proteasome activator Bpa (also referred to as PafE), and that appears to play a role under stress conditions. In this review, mechanistic principles of bacterial proteasomal degradation are discussed and compared with functionally related elements of the eukaryotic ubiquitin-proteasome system. Special attention is given to an understanding on the molecular level based on structural and biochemical analysis. Wherever available, discussion of in vivo studies is included to highlight the biological significance of this unusual bacterial degradation pathway. PMID:26352358

  3. Rapid Water Uptake and Limited Storage Capacity at Height of Growing Season in Four Temperate Tree Species in a Central Pennsylvania Catchment

    NASA Astrophysics Data System (ADS)

    Gaines, K.; Meinzer, F. C.; Duffy, C.; Thomas, E.; Eissenstat, D. M.

    2014-12-01

    rapid water uptake and tree water storage limited to about a month in duration. These findings are necessary for modeling of hydrologic parameters that are influenced by tree water age. They also indicate that trees on shallow soil in this catchment may be at risk if droughts lasting over a month occur more frequently in future years.

  4. Concurrent Nontuberculous Mycobacteria Infection and High-Grade Anterior Mediastinal Extraskeletal Osteosarcoma (ESOS): Is There a Connection?

    PubMed Central

    Faz, Gabriel T.; Eltorky, Mahmoud; Karnath, Bernard

    2016-01-01

    Patient: Male, 59 Final Diagnosis: High-grade anterior mediastinal extraskeletal osteosarcoma Symptoms: Dyspnea • hemoptysis Medication: — Clinical Procedure: Biopsy Specialty: Oncology Objective: Rare disease Background: Extraskeletal osteosarcomas (ESOS) of the mediastinum are extremely rare and may present with concurrent nontuberculous mycobacteria infection. Case Report: We present the second documented case of high-grade anterior mediastinal extraskeletal osteosarcoma in a 59-year-old man with a history of treated, latent tuberculosis (TB). Sputum samples grew Mycoplasma avium complex and Mycobacterium fortuitum. Imaging showed a right-sided 7.6 cm mass with compression of the main bronchus. Subsequent biopsy with vimentin staining established the diagnosis of ESOS. Due to the patient’s rapidly declining performance status, he was not deemed a candidate for surgery or chemotherapy. He subsequently expired within one month of presentation. Conclusions: We present a unique case of high-grade anterior mediastinum ESOS and a review of the literature regarding all documented cases of ESOS to date. We suggest there is a possible link between mediastinal masses and nontuberculous mycobacteria infection. PMID:27539718

  5. Antimicrobial Susceptibility Testing, Drug Resistance Mechanisms, and Therapy of Infections with Nontuberculous Mycobacteria

    PubMed Central

    Nash, Kevin A.; Wallace, Richard J.

    2012-01-01

    Summary: Within the past 10 years, treatment and diagnostic guidelines for nontuberculous mycobacteria have been recommended by the American Thoracic Society (ATS) and the Infectious Diseases Society of America (IDSA). Moreover, the Clinical and Laboratory Standards Institute (CLSI) has published and recently (in 2011) updated recommendations including suggested antimicrobial and susceptibility breakpoints. The CLSI has also recommended the broth microdilution method as the gold standard for laboratories performing antimicrobial susceptibility testing of nontuberculous mycobacteria. This article reviews the laboratory, diagnostic, and treatment guidelines together with established and probable drug resistance mechanisms of the nontuberculous mycobacteria. PMID:22763637

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

    PubMed

    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.

  7. Benzoic Acid-Inducible Gene Expression in Mycobacteria

    PubMed Central

    Dragset, Marte S.; Barczak, Amy K.; Kannan, Nisha; Mærk, Mali; Flo, Trude H.; Valla, Svein; Rubin, Eric J.; Steigedal, Magnus

    2015-01-01

    Conditional expression is a powerful tool to investigate the role of bacterial genes. Here, we adapt the Pseudomonas putida-derived positively regulated XylS/Pm expression system to control inducible gene expression in Mycobacterium smegmatis and Mycobacterium tuberculosis, the causative agent of human tuberculosis. By making simple changes to a Gram-negative broad-host-range XylS/Pm-regulated gene expression vector, we prove that it is possible to adapt this well-studied expression system to non-Gram-negative species. With the benzoic acid-derived inducer m-toluate, we achieve a robust, time- and dose-dependent reversible induction of Pm-mediated expression in mycobacteria, with low background expression levels. XylS/Pm is thus an important addition to existing mycobacterial expression tools, especially when low basal expression is of particular importance. PMID:26348349

  8. Current Epidemiologic Trends of the Nontuberculous Mycobacteria (NTM).

    PubMed

    Falkinham, Joseph O

    2016-06-01

    The nontuberculous mycobacteria (NTM) are waterborne opportunistic pathogens of humans. They are normal inhabitants of premise plumbing, found, for example, in household and hospital shower heads, water taps, aerators, and hot tubs. The hydrophobic NTM are readily aerosolized, and pulmonary infections and hypersensitivity pneumonitis have been traced to the presence of NTM in shower heads. Hypersensitivity pneumonitis in automotive workers was traced to the presence of NTM in metal recovery fluid used in grinding operations. Recently, NTM bacteremia in heart transplant patients has been traced to the presence of NTM in water reservoirs of instruments employed in operating rooms to heat and cool patient blood during periods of mechanical circulation. Although NTM are difficult to eradicate from premise plumbing as a consequence of their disinfectant-resistance and formation of biofilms, measures such as reduction of turbidity and reduction in carbon and nitrogen for growth and the installation of microbiological filters can reduce exposure of NTM to susceptible individuals. PMID:27020801

  9. Chemical basis of rough and smooth variation in mycobacteria.

    PubMed Central

    Belisle, J T; Brennan, P J

    1989-01-01

    Rough and smooth colony variants of Mycobacterium kansasii were compared with respect to surface glycolipid composition. Thin-layer chromatography of the native glycolipid antigens, gas chromatography of the constituent sugars, and in situ probing with an appropriate monoclonal antibody by colony dot blot enzyme-linked immunosorbent assay and immunogold labeling demonstrated that all M. kansasii strains of smooth colony morphology contain on their surfaces the recently described trehalose-containing lipooligosaccharides, whereas all rough variants were devoid of such surface antigens. Yet all strains, rough and smooth, contained another glycolipid, the M. kansasii-specific phenolic glycolipid. Previous studies by others had shown that the rough forms of M. kansasii persist longer than smooth variants in experimentally infected mice. Therefore, this study may provide some insight into the question of the chemical basis of pathogenesis in certain mycobacteria. Images PMID:2722755

  10. Identification of a Copper-Binding Metallothionein in Pathogenic Mycobacteria

    PubMed Central

    Gold, Ben; Deng, Haiteng; Bryk, Ruslana; Vargas, Diana; Eliezer, David; Roberts, Julia; Jiang, Xiuju; Nathan, Carl

    2009-01-01

    A screen of a genomic library from Mycobacterium tuberculosis (Mtb) identified a small, unannotated open reading frame (MT0196) that encodes a 4.9-kDa, cysteine-rich protein. Despite extensive nucleotide divergence, the amino acid sequence is highly conserved among mycobacteria that are pathogenic in vertebrate hosts. We synthesized the protein and found that it preferentially bound up to 6 Cu(I) ions in a solvent-shielded core. Copper, cadmium and compounds that generate nitric oxide or superoxide induced the gene’s expression in Mtb up to a thousand-fold. The native protein bound copper within Mtb and partially protected Mtb from copper toxicity. We propose that the product of the MT0196 gene be named mycobacterial metallothionien (MymT). To our knowledge, MymT is the first metallothionein of a Gram-positive bacterium with a demonstrated function. PMID:18724363

  11. “Multidrug-resistant tuberculosis” may be nontuberculous mycobacteria

    PubMed Central

    Shahraki, Abdolrazagh Hashemi; Heidarieh, Parvin; Bostanabad, Saeed Zaker; Khosravi, Azar Dokht; Hashemzadeh, Mohammad; Khandan, Solmaz; Biranvand, Maryam; Schraufnagel, Dean E.; Mirsaeidi, Mehdi

    2015-01-01

    Introduction Multidrug resistant tuberculosis (MDR-TB) presents a great challenge to public health, especially for developing countries. Some nontuberculous mycobacteria (NTM) cause the similar clinical and radiological characteristics with tuberculosis. We aimed to identify the frequency of NTM infections among subjects who were suspected to have MDR-TB due to lack of response to anti-TB treatment. Methods This retrospective study evaluated patients with suspected MDR-TB due to lack of sputum conversion after 2–3 months therapy with first line anti-TB treatment from 2009 through 2014. Cultures for mycobacteria were performed and identification was done to species level by phenotypic and molecular tests. The outcome of the patients with NTM disease and related risk factors for poor outcome were evaluated. Results Out of 117 consecutive strains isolated from suspected MDR-TB subjects, 35 (30%) strains were identified as NTM by using conventional and molecular approaches. Of these patients with positive NTM cultures, 32 (27%) patients met ATS/IDSA diagnostic criteria. Out of 32, 29 (90%) individuals with confirmed NTM diseases had underlying disorders including 8 subjects with malignancy, 5 with organ transplantations, and 4 with the human immunodeficiency virus. No known underlying disorder was found in 3 (9%) subjects. Treatment outcomes were available for 27 subjects, 17 (63%) of whom were cured and 10 (37%) had poor outcome including 6 (60%) who failed and 4 (40%) who died during treatment. Conclusion The high costs to the patient and society should lead health care providers to consider NTM in all patients suspected of having TB. PMID:25784643

  12. Conformational analyses of mycothiol, a critical intracellular glycothiol in Mycobacteria.

    PubMed

    Hand, Christine E; Auzanneau, France-Isabelle; Honek, John F

    2006-07-01

    Intracellular thiols are essential biomolecules, which play several critical roles in living organisms including controlling intracellular redox potential and acting as cofactors for several vital detoxification enzymes including S-transferases and formaldehyde dehydrogenases. The tripeptide gamma-L-glutamyl-L-cysteinylglycine, more commonly known as glutathione, is well known as the major intracellular thiol in eukaryotes and in some bacteria. However, glutathione is absent in the Actinomycetales bacteria such as Mycobacteria and Streptomyces and is believed to be replaced by 1-D-myo-inosityl-2-(N-acetyl-L-cysteinyl)amido-2-deoxy-alpha-D-glucopyranoside, mycothiol, in these organisms. Although much is known about the chemistry and biochemistry of glutathione, currently much less is known concerning mycothiol and its properties. The structure of mycothiol is composed of a glycoside linkage between myo-inositol and D-glucosamine with an N-acetyl-L-cysteine linked to the 2'-amino group of the d-glucosamine moiety. Mycothiol is currently of intense interest due to its essential role in the cellular physiology of Mycobacteria, such as Mycobacterium tuberculosis, and its possible role in antimycobacterial drug resistance. A detailed investigation of its chemistry is therefore essential in ameliorating our knowledge of this key glycothiol, and in shedding additional light on its biochemical role in these pathogenic organisms. This report presents a detailed conformational analysis of mycothiol utilizing a variety of force fields and stochastic search protocols. Cluster analyses of energetically low lying conformations have indicated the presence of several key conformations that are populated in the gas phase and with implicit water solvation. These conformations are compared to recent NMR studies on a derivative of mycothiol. This information should be an important contribution to our basic understanding of the chemistry of this glycothiol and critical in the design of

  13. Nontuberculous Mycobacteria: An Underestimated Cause of Bioprosthetic Valve Infective Endocarditis

    PubMed Central

    Bouchiat, Coralie; Saison, Julien; Boisset, Sandrine; Flandrois, Jean-Pierre; Issartel, Bertrand; Dauwalder, Olivier; Benito, Yvonne; Jarraud, Sophie; Grando, Jacqueline; Boibieux, Andre; Dumitrescu, Oana; Delahaye, François; Farhat, Fadi; Thivolet-Bejui, Françoise; Frieh, Jean-Philippe; Vandenesch, François

    2015-01-01

    Background. Atypical mycobacteria, or nontuberculous mycobacteria (NTM), have been barely reported as infective endocarditis (IE) agents. Methods. From January 2010 to December 2013, cardiac valve samples sent to our laboratory as cases of blood culture-negative suspected IE were analyzed by 16S rDNA polymerase chain reaction (PCR). When positive for NTM, hsp PCR allowed species identification. Demographic, clinical, echocardiographic, histopathological, and Ziehl-Neelsen staining data were then collected. Results. Over the study period, 6 of 370 cardiac valves (belonging to 5 patients in 3 hospitals) were positive for Mycobacterium chelonae (n = 5) and Mycobacterium lentiflavum (n = 1) exclusively on bioprosthetic material. The 5 patients presented to the hospital for heart failure without fever 7.1–18.9 months (median 13.1 months) after biological prosthetic valve implantation. Echocardiography revealed paravalvular regurgitation due to prosthesis dehiscence in all patients. Histopathological examination of the explanted material revealed inflammatory infiltrates in all specimens, 3 of which were associated with giant cells. Gram staining and conventional cultures remained negative, whereas Ziehl-Neelsen staining showed acid-fast bacilli in all patients. Allergic etiology was ruled out by antiporcine immunoglobulin E dosages. These 5 cases occurred exclusively on porcine bioprosthetic material, revealing a statistically significant association between bioprosthetic valves and NTM IE (P < .001). Conclusions. The body of evidence confirmed the diagnosis of prosthetic IE. The statistically significant association between bioprosthetic valves and NTM IE encourages systematic Ziehl-Neelsen staining of explanted bioprosthetic valves in case of early bioprosthesis dysfunction, even without an obvious sign of IE. In addition, we strongly question the cardiac bioprosthesis conditioning process after animal sacrifice. PMID:26213691

  14. Three-Dimensional Evaluation of the Upper Airway Morphological Changes in Growing Patients with Skeletal Class III Malocclusion Treated by Protraction Headgear and Rapid Palatal Expansion: A Comparative Research

    PubMed Central

    Liu, Ju; Wu, Zizhong; Xie, Yongtao; Li, Liang; Liu, Hong; Guo, Tiantian; Chen, Chen; Zhang, Shijie

    2015-01-01

    Objective The aim of this study was to evaluate the morphological changes of upper airway after protraction headgear and rapid maxillary expansion (PE) treatment in growing patients with Class III malocclusion and maxillary skeletal deficiency compared with untreated Class III patients by cone-beam computed tomography (CBCT). Methods Thirty growing patients who have completed PE therapy were included in PE group. The control group (n = 30) was selected from the growing untreated patients with the same diagnosis. The CBCT scans of the pre-treatment (T1) and post-treatment (T2) of PE group and the control group were collected. Reconstruction and registration of the 3D models of T1 and T2 were completed. By comparing the data obtained from T1, T2 and control group, the morphological changes of the upper airway during the PE treatment were evaluated. Results Comparing with the data from T1 group, the subspinale (A) of maxilla and the upper incisor (UI) of the T2 group were moved in the anterior direction. The gnathion (Gn) of mandible was moved in the posterior-inferior direction. The displacement of the hyoid bone as well as the length and width of dental arch showed significant difference. The volume and mean cross-sectional area of nasopharynx, velopharynx and glossopharynx region showed significant difference. The largest anteroposterior/the largest lateral (AP/LR) ratios of the velopharynx and glossopharynx were increased, but the AP/LR ratio of the hypopharynx was decreased. In addition, the length and width of the maxillary dental arch, the displacement of the hyoid bone, the volume of nasopharynx and velopharynx, and the AP/LR ratio of the hypopharynx and velopharynx showed significant difference between the data from control and T2 group. Conclusion The PE treatment of Class Ⅲ malocclusion with maxillary skeletal hypoplasia leads to a significant increase in the volume of nasopharynx and velopharynx. PMID:26252015

  15. Trehalose Polyphleates Are Produced by a Glycolipid Biosynthetic Pathway Conserved across Phylogenetically Distant Mycobacteria.

    PubMed

    Burbaud, Sophie; Laval, Françoise; Lemassu, Anne; Daffé, Mamadou; Guilhot, Christophe; Chalut, Christian

    2016-02-18

    Mycobacteria synthesize a variety of structurally related glycolipids with major biological functions. Common themes have emerged for the biosynthesis of these glycolipids, including several families of proteins. Genes encoding these proteins are usually clustered on bacterial chromosomal islets dedicated to the synthesis of one glycolipid family. Here, we investigated the function of a cluster of five genes widely distributed across non-tuberculous mycobacteria. Using defined mutant analysis and in-depth structural characterization of glycolipids from wild-type or mutant strains of Mycobacterium smegmatis and Mycobacterium abscessus, we established that they are involved in the formation of trehalose polyphleates (TPP), a family of compounds originally described in Mycobacterium phlei. Comparative genomics and lipid analysis of strains distributed along the mycobacterial phylogenetic tree revealed that TPP is synthesized by a large number of non-tuberculous mycobacteria. This work unravels a novel glycolipid biosynthetic pathway in mycobacteria and extends the spectrum of bacteria that produce TPP. PMID:27028886

  16. Series of Case Patients with Nontuberculous Mycobacteria Isolation, Central North Carolina, 2006-2010

    EPA Science Inventory

    Nontuberculous mycobacteria (NTM) infection/colonization, associated with human morbidity/mortality, is linked to drinking water and drinking water distribution systems. To characterize rates and distribution of NTM isolation among residents living in three North Carolina countie...

  17. Virulence, biochemistry, morphology and host-interacting properties of detergent-free cultured mycobacteria: An update.

    PubMed

    Leisching, G; Pietersen, R-D; Wiid, I; Baker, B

    2016-09-01

    The culturing of mycobacteria is a standard procedure that is consistent world-wide, with little variation in the growth media constituents, particularly those found in liquid and solid media. Before the 1940s however, the aggregating nature of mycobacteria as well as the characteristic slow growth-rate saw mycobacterial research delay considerably. Dubos and colleagues addressed both these issues and observed that a very small volume of Tween detergent was sufficient to greatly improve the culturing of mycobacteria. Over the years however, evidence of the unfavourable effects of this detergent on a number of morphological, biochemical, pathogenic and host-interacting properties of mycobacteria surfaced. For the first time we bring together literature, past and present to comprehensively review the mycobacterial properties which are, and are not affected by the use of this detergent. We also address other detergents and methods which may circumvent the need to include Tween compounds in mycobacterial culture media. PMID:27553410

  18. Nontuberculous mycobacteria isolations from residents of three counties in North Carolina, 2006 – 2010

    EPA Science Inventory

    Background: Nontuberculous mycobacteria (NTM) are emerging infections among the elderly and immunocompromised but the epidemiology is poorly characterized. Reports of NTM isolation from clinical specimens is a readily available, if imperfect surrogate for disease prevalence. Meth...

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

    EPA Science Inventory

    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...

  20. Rv3080c regulates the rate of inhibition of mycobacteria by isoniazid through FabD.

    PubMed

    Kumari, Ruma; Saxena, Richa; Tiwari, Sameer; Tripathi, Dinesh K; Srivastava, Kishore K

    2013-02-01

    The mycobacterial FASII multi-enzyme complex has been identified to be a target of Ser/Thr protein kinases (STPKs) of Mycobacterium tuberculosis (MTB), with substrates, including the malonyl-CoA:ACP transacylase (FabD) and the β-ketoacyl-ACP synthases KasA and KasB. These proteins are phosphorylated by various kinases in vitro. The present study links the correlation of FASII pathway with serine threonine protein kinase of MTB. In the preliminary finding, we have shown that mycobacterial protein Rv3080c (PknK) phosphorylates FabD and the knockdown of PknK protein in mycobacteria down regulates FabD expression. This event leads to the differential inhibition of mycobacteria in the presence of isoniazid (INH), as the inhibition of growth of mycobacteria in the presence of INH is enhanced in PknK deficient mycobacteria. PMID:23180244

  1. Rapid Identification of Mycobacterium Species with the Aid of Multiplex Polymerase Chain Reaction (PCR) From Clinical Isolates

    PubMed Central

    Gupta, Siddhartha; Bandyopadhyay, Debasis; Paine, Suman Kalyan; Gupta, Soma; Banerjee, Surajita; Bhattacharya, Sujata; Gachhui, Ratan; Bhattacharya, Basudev

    2010-01-01

    Mycobacteria are aerobic, nonspore forming, non-motile,single-cell bacteria.Of more than 40 currently recognized species of mycobacteria, Mycobacterium tuberculosis, the causative agent of human TB is the commonest pathogen for pulmonary and extra pulmonary tuberculosis cases. The other members of the Mycobacterium tuberculosis complex (MTC) or the nontubercular mycobacterium (NTM) produces similar diseases which cannot be differentiated from tuberculosis by clinical symptoms and signs. But this differentiation is important as the chemotherapy varies widely according to the strain of mycobacterium. The burden of morbidity and mortality of tuberculosis is rapidly growing worldwide, particularly with the HIV/AIDS epidemic. The strain identification of Mycobacterium remains a cumbersome, labor intensive and expensive procedure, which requires 3 to 12 weeks of time. The conventional methods of strain identification lack proper standardization and precise diagnosis. The prime objective of this study is to overcome these problems. A multiplex PCR using 3 amplicons of 165,365, and 541 base pair target sequences was done with a total number of 165 clinical isolates of suspected Koch’s patients. Strain identification was compared both by conventional methods and multiplex PCR. The results of the study show that this multiplex PCR is supposed to be less complicated, less time consuming, cost-effective and superior to the conventional methods. It is also applicable for culture negative samples where strain identification is not possible by conventional approach. PMID:21258579

  2. Fine-tuning the space, time, and host distribution of mycobacteria in wildlife

    PubMed Central

    2011-01-01

    Background We describe the diversity of two kinds of mycobacteria isolates, environmental mycobacteria and Mycobacterium bovis collected from wild boar, fallow deer, red deer and cattle in Doñana National Park (DNP, Spain), analyzing their association with temporal, spatial and environmental factors. Results High diversity of environmental mycobacteria species and M. bovis typing patterns (TPs) were found. When assessing the factors underlying the presence of the most common types of both environmental mycobacteria and M. bovis TPs in DNP, we evidenced (i) host species differences in the occurrence, (ii) spatial structuration and (iii) differences in the degree of spatial association of specific types between host species. Co-infection of a single host by two M. bovis TPs occurred in all three wild ungulate species. In wild boar and red deer, isolation of one group of mycobacteria occurred more frequently in individuals not infected by the other group. While only three TPs were detected in wildlife between 1998 and 2003, up to 8 different ones were found during 2006-2007. The opposite was observed in cattle. Belonging to an M. bovis-infected social group was a significant risk factor for mycobacterial infection in red deer and wild boar, but not for fallow deer. M. bovis TPs were usually found closer to water marshland than MOTT. Conclusions The diversity of mycobacteria described herein is indicative of multiple introduction events and a complex multi-host and multi-pathogen epidemiology in DNP. Significant changes in the mycobacterial isolate community may have taken place, even in a short time period (1998 to 2007). Aspects of host social organization should be taken into account in wildlife epidemiology. Wildlife in DNP is frequently exposed to different species of non-tuberculous, environmental mycobacteria, which could interact with the immune response to pathogenic mycobacteria, although the effects are unknown. This research highlights the suitability of

  3. Real-time PCR detection of environmental mycobacteria in house dust.

    PubMed

    Torvinen, Eila; Torkko, Pirjo; Rintala, Aino Nevalainen Helena

    2010-07-01

    Analysing the number and species of microbes in indoor dust is needed for assessment of human exposure to microbes in dwellings. Environmental mycobacteria are common heterotrophic bacteria in both natural and man-made environments and potential inducers of human immune system. Culture of mycobacteria from samples rich with other microbes is difficult due to the slow growth rate of mycobacteria and this has hampered the studies on their role in indoor human exposure. A quantitative, real-time 5'-nuclease (TaqMan) PCR assay was developed to detect environmental mycobacteria in indoor dust samples. The specificity of the primers and the probe targeting the 16S rDNA of mycobacteria, tested with 26 mycobacterial and 10 non-mycobacterial but related species, proved to be high. When tested on 20 indoor dust samples collected from five homes, the assay gave counts varying between 4.8 x 10(4) and 7.2 x 10(6)cell/g, being on average 1.1 x 10(3) times higher than culture. Seasonal variation in the dust counts of mycobacteria was observed by both culture and qPCR. Total of 140 isolates considered as mycobacteria by Ziehl-Neelsen staining and GLC-analyses were subjected to PCR analysis with the mycobacterial primers, and 39 isolates to partial 16S rDNA sequencing. All proved to be mycobacteria and revealed high diversity of mycobacterial species in the dust samples. Majority of the sequences were related to M. terrae and M. avium complexes. PMID:20434494

  4. Microscopy, Culture, and Quantitative Real-Time PCR Examination Confirm Internalization of Mycobacteria in Plants

    PubMed Central

    Lvoncik, S.; Slana, I.; Kulich, P.; Kralik, P.

    2014-01-01

    The environment is a reservoir of nontuberculous mycobacteria and is considered a source of infection for animals and humans. Mycobacteria can persist in different types of environments for a relatively long time. We have studied their possible internalization into plant tissue through intact, as well as damaged, root systems of different types of plants grown in vitro and under field conditions. The substrate into which plants were seeded was previously contaminated with different strains of Mycobacterium avium (108 to 1010 cells/g of soil) and feces from animals with paratuberculosis. We detected M. avium subsp. avium, hominissuis, and paratuberculosis in the stems and leaves of the plants by both culture and real-time quantitative PCR. The presence of mycobacteria in the plant tissues was confirmed by microscopy. The concentration of mycobacteria found inside plant tissue was several orders of magnitude lower (up to 104 cells/g of tissue) than the initial concentration of mycobacteria present in the culture medium or substrate. These findings led us to the hypothesis that plants may play a role in the spread and transmission of mycobacteria to other organisms in the environment. PMID:24747896

  5. DOUBLE-STEP MULTIPLEX REAL TIME PCR WITH MELTING CURVE ANALYSIS FOR DETECTION AND DIFFERENTIATION OF MYCOBACTERIA IN SPUTUM.

    PubMed

    Kasa, Sawinee; Faksri, Kiatichai; Kaewkes, Wanlop; Lulitanond, Viraphong; Namwat, Wises

    2015-01-01

    Mycobacterium tuberculosis (M. tb) is a causative agent of tuberculosis, a worldwide public health problem. In recent years, the incidence of human mycobacterial infection due to species other than M. tb has increased. However, the lack of specific, rapid, and inexpensive methods for identification of mycobacterial species remains a pressing problem. A diagnostic test was developed for mycobacterial strain differentiation utilizing a double-step multiplex real time PCR together with melting curve analysis for identifying and distinguishing among M. tb, M. bovis BCG, other members of M. tb. complex, M. avium, and non-tuberculosis mycobacteria. The assay was tested using 167 clinical sputum samples in comparison with acid-fast staining and culturing. Using only the first step (step A) the assay achieved sensitivity and specificity of 81% and 95%, respectively. The detection limit was equivalent to 50 genome copies.

  6. DOUBLE-STEP MULTIPLEX REAL TIME PCR WITH MELTING CURVE ANALYSIS FOR DETECTION AND DIFFERENTIATION OF MYCOBACTERIA IN SPUTUM.

    PubMed

    Kasa, Sawinee; Faksri, Kiatichai; Kaewkes, Wanlop; Lulitanond, Viraphong; Namwat, Wises

    2015-01-01

    Mycobacterium tuberculosis (M. tb) is a causative agent of tuberculosis, a worldwide public health problem. In recent years, the incidence of human mycobacterial infection due to species other than M. tb has increased. However, the lack of specific, rapid, and inexpensive methods for identification of mycobacterial species remains a pressing problem. A diagnostic test was developed for mycobacterial strain differentiation utilizing a double-step multiplex real time PCR together with melting curve analysis for identifying and distinguishing among M. tb, M. bovis BCG, other members of M. tb. complex, M. avium, and non-tuberculosis mycobacteria. The assay was tested using 167 clinical sputum samples in comparison with acid-fast staining and culturing. Using only the first step (step A) the assay achieved sensitivity and specificity of 81% and 95%, respectively. The detection limit was equivalent to 50 genome copies. PMID:26513906

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

    USGS Publications Warehouse

    Rhodes, M.W.; Kator, H.; Kotob, S.; van Berkum, P.; Kaattari, I.; Vogelbein, W.; Quinn, F.; Floyd, M.M.; Butler, W.R.; Ottinger, C.A.

    2003-01-01

    Slowly growing, non-pigmented mycobacteria were isolated from striped bass (Morone saxatilis) during an epizootic of mycobacteriosis in the Chesapeake Bay. Growth characteristics, acid-fastness and results of 16S rRNA gene sequencing were consistent with those of the genus Mycobacterium. A unique profile of biochemical reactions was observed among the 21 isolates. A single cluster of eight peaks identified by analysis of mycolic acids (HPLC) resembled those of reference patterns but differed in peak elution times from profiles of reference species of the Mycobacterium tuberculosis complex. One isolate (M175T) was placed within the slowly growing mycobacteria by analysis of aligned 16S rRNA gene sequences and was proximate in phylogeny to Mycobacterium ulcerans and Mycobacterium marinum. However, distinct nucleotide differences were detected in the 16S rRNA gene sequence among M175T, M. ulcerans and M. marinum (99.2% similarity). Isolate M175T could be differentiated from other slowly growing, non-pigmented mycobacteria by its inability to grow at 37??C, production of niacin and urease, absence of nitrate reductase and resistance to isoniazid (1 ??g ml-1), thiacetazone and thiophene-2-carboxylic hydrazide. Based upon these genetic and phenotypic differences, isolate M175T (= ATCC 700981T = NCTC 13215T) is proposed as the type strain of a novel species, Mycobacterium shottsii sp. nov.

  8. Multiphasic strain differentiation of atypical mycobacteria from elephant trunk wash.

    PubMed

    Chan, Kok-Gan; Loke, Mun Fai; Ong, Bee Lee; Wong, Yan Ling; Hong, Kar Wai; Tan, Kian Hin; Kaur, Sargit; Ng, Hien Fuh; Abdul Razak, Mfa; Ngeow, Yun Fong

    2015-01-01

    Background. Two non-tuberculous mycobacterial strains, UM_3 and UM_11, were isolated from the trunk wash of captive elephants in Malaysia. As they appeared to be identical phenotypes, they were investigated further by conventional and whole genome sequence-based methods of strain differentiation. Methods. Multiphasic investigations on the isolates included species identification with hsp65 PCR-sequencing, conventional biochemical tests, rapid biochemical profiling using API strips and the Biolog Phenotype Microarray analysis, protein profiling with liquid chromatography-mass spectrometry, repetitive sequence-based PCR typing and whole genome sequencing followed by phylogenomic analyses. Results. The isolates were shown to be possibly novel slow-growing schotochromogens with highly similar biological and genotypic characteristics. Both strains have a genome size of 5.2 Mbp, G+C content of 68.8%, one rRNA operon and 52 tRNAs each. They qualified for classification into the same species with their average nucleotide identity of 99.98% and tetranucleotide correlation coefficient of 0.99999. At the subspecies level, both strains showed 98.8% band similarity in the Diversilab automated repetitive sequence-based PCR typing system, 96.2% similarity in protein profiles obtained by liquid chromatography mass spectrometry, and a genomic distance that is close to zero in the phylogenomic tree constructed with conserved orthologs. Detailed epidemiological tracking revealed that the elephants shared a common habitat eight years apart, thus, strengthening the possibility of a clonal relationship between the two strains.

  9. Multiphasic strain differentiation of atypical mycobacteria from elephant trunk wash

    PubMed Central

    Chan, Kok-Gan; Loke, Mun Fai; Ong, Bee Lee; Wong, Yan Ling; Hong, Kar Wai; Tan, Kian Hin; Kaur, Sargit; Ng, Hien Fuh; Abdul Razak, MFA

    2015-01-01

    Background. Two non-tuberculous mycobacterial strains, UM_3 and UM_11, were isolated from the trunk wash of captive elephants in Malaysia. As they appeared to be identical phenotypes, they were investigated further by conventional and whole genome sequence-based methods of strain differentiation. Methods. Multiphasic investigations on the isolates included species identification with hsp65 PCR-sequencing, conventional biochemical tests, rapid biochemical profiling using API strips and the Biolog Phenotype Microarray analysis, protein profiling with liquid chromatography-mass spectrometry, repetitive sequence-based PCR typing and whole genome sequencing followed by phylogenomic analyses. Results. The isolates were shown to be possibly novel slow-growing schotochromogens with highly similar biological and genotypic characteristics. Both strains have a genome size of 5.2 Mbp, G+C content of 68.8%, one rRNA operon and 52 tRNAs each. They qualified for classification into the same species with their average nucleotide identity of 99.98% and tetranucleotide correlation coefficient of 0.99999. At the subspecies level, both strains showed 98.8% band similarity in the Diversilab automated repetitive sequence-based PCR typing system, 96.2% similarity in protein profiles obtained by liquid chromatography mass spectrometry, and a genomic distance that is close to zero in the phylogenomic tree constructed with conserved orthologs. Detailed epidemiological tracking revealed that the elephants shared a common habitat eight years apart, thus, strengthening the possibility of a clonal relationship between the two strains. PMID:26587340

  10. Multiphasic strain differentiation of atypical mycobacteria from elephant trunk wash.

    PubMed

    Chan, Kok-Gan; Loke, Mun Fai; Ong, Bee Lee; Wong, Yan Ling; Hong, Kar Wai; Tan, Kian Hin; Kaur, Sargit; Ng, Hien Fuh; Abdul Razak, Mfa; Ngeow, Yun Fong

    2015-01-01

    Background. Two non-tuberculous mycobacterial strains, UM_3 and UM_11, were isolated from the trunk wash of captive elephants in Malaysia. As they appeared to be identical phenotypes, they were investigated further by conventional and whole genome sequence-based methods of strain differentiation. Methods. Multiphasic investigations on the isolates included species identification with hsp65 PCR-sequencing, conventional biochemical tests, rapid biochemical profiling using API strips and the Biolog Phenotype Microarray analysis, protein profiling with liquid chromatography-mass spectrometry, repetitive sequence-based PCR typing and whole genome sequencing followed by phylogenomic analyses. Results. The isolates were shown to be possibly novel slow-growing schotochromogens with highly similar biological and genotypic characteristics. Both strains have a genome size of 5.2 Mbp, G+C content of 68.8%, one rRNA operon and 52 tRNAs each. They qualified for classification into the same species with their average nucleotide identity of 99.98% and tetranucleotide correlation coefficient of 0.99999. At the subspecies level, both strains showed 98.8% band similarity in the Diversilab automated repetitive sequence-based PCR typing system, 96.2% similarity in protein profiles obtained by liquid chromatography mass spectrometry, and a genomic distance that is close to zero in the phylogenomic tree constructed with conserved orthologs. Detailed epidemiological tracking revealed that the elephants shared a common habitat eight years apart, thus, strengthening the possibility of a clonal relationship between the two strains. PMID:26587340

  11. Radiometric measurement of differential metabolism of fatty acid by mycobacteria

    SciTech Connect

    Camargo, E.E.; Kertcher, J.A.; Larson, S.M.; Tepper, B.S.; Wagner, H.N. Jr.

    1982-06-01

    An assay system has been developed based on automated radiometric quantification of /sup 14/CO2 produced through oxidation of (1-/sup 14/C) fatty acids by mycobacteria. Two stains of M. tuberculosis (H37Rv and Erdman) and one of M. bovis (BCG) in 7H9 medium (ADC) with 1.0 microCi of one of the fatty acids (butyric, hexanoic, octanoic, decanoic, lauric, myristic, palmitic, stearic, oleic, linoleic and linolenic) were studied. Results previously published on M. lepraemurium (Hawaiian) were also included for comparison. Both strains of M. tuberculosis had maximum /sup 14/CO2 production from hexanoic acid. Oxidation of butyric and avid oxidation of lauric acids were also found with the H37Rv strain but not with Erdman. In contrast, /sup 14/CO2 production by M. bovis was greatest from lauric and somewhat less from decanoic acid. M. lepraemurium showed increasing oxidation rates from myristic, decanoic and lauric acids. Assimilation studies of M. tuberculosis H37Rv confirmed that most of the oxidized substrates were converted into by-products with no change in those from which no oxidation was found. These data suggest that the radiometric measurement of differential fatty acid metabolism may provide a basis of strain identification of the genus Mycobacterium.

  12. Update on pulmonary disease due to non-tuberculous mycobacteria.

    PubMed

    Stout, Jason E; Koh, Won-Jung; Yew, Wing Wai

    2016-04-01

    Non-tuberculous mycobacteria (NTM) are emerging worldwide as significant causes of chronic pulmonary infection, posing a number of challenges for both clinicians and researchers. While a number of studies worldwide have described an increasing prevalence of NTM pulmonary disease over time, population-based data are relatively sparse and subject to ascertainment bias. Furthermore, the disease is geographically heterogeneous. While some species are commonly implicated worldwide (Mycobacterium avium complex, Mycobacterium abscessus), others (e.g., Mycobacterium malmoense, Mycobacterium xenopi) are regionally important. Thoracic computed tomography, microbiological testing with identification to the species level, and local epidemiology must all be taken into account to accurately diagnose NTM pulmonary disease. A diagnosis of NTM pulmonary disease does not necessarily imply that treatment is required; a patient-centered approach is essential. When treatment is required, multidrug therapy based on appropriate susceptibility testing for the species in question should be used. New diagnostic and therapeutic modalities are needed to optimize the management of these complicated infections. PMID:26976549

  13. DprE1, a new taxonomic marker in mycobacteria.

    PubMed

    Incandela, Maria Loreto; Perrin, Elena; Fondi, Marco; de Jesus Lopes Ribeiro, Ana Luisa; Mori, Giorgia; Moiana, Alessia; Gramegna, Maurizio; Fani, Renato; Riccardi, Giovanna; Pasca, Maria Rosalia

    2013-11-01

    Among the species of the Mycobacterium genus, more than 50 have been recognized as human pathogens. In spite of the different diseases caused by mycobacteria, the interspecies genetic similarity ranges from 94% to 100%, and for some species, this value is higher than in other bacteria. Consequently, it is important to understand the relationships existing among mycobacterial species. In this context, the possibility to use Mycobacterium tuberculosis dprE1 gene as new phylogenetic/taxonomic marker has been explored. The dprE1 gene codes for the target of benzothiazinones, belonging to a very promising class of antitubercular drugs. Mutations in cysteine 387 of DprE1 are responsible for benzothiazinone resistance. The DprE1 tree, obtained with 73 amino acid sequences of mycobacterial species, revealed that concerning the benzothiazinone sensitivity/resistance, it is possible to discriminate two clusters. To validate it, a concatamer obtained from the amino acid sequences of nine mycobacterial housekeeping genes was performed. The concatamer revealed that there is no separation between the benzothiazinone-susceptible and benzothiazinone-resistant species; consequently, this parameter is not linked to the phylogeny. DprE1 tree might represent a good taxonomic marker for the assignment of a mycobacterial isolate to a species. Moreover, the concatamer represents a good reference phylogeny for the Mycobacterium genus. PMID:24024613

  14. Nontuberculous Mycobacteria Isolated from Tuberculosis Suspects in Ibadan, Nigeria

    PubMed Central

    Cadmus, Simeon Idowu; Diarra, Bassirou; Traore, Brehima; Maiga, Mamoudou; Siddiqui, Sophia; Tounkara, Anatole; Falodun, Olutayo; Lawal, Wole; Adewole, Isaac Folurunso; Murphy, Rob; van Soolingen, Dick; Taiwo, Babafemi

    2016-01-01

    In Nigeria, one of the highest tuberculosis (TB) burdened nations, sputum smear microscopy is routinely employed for TB diagnosis at Directly Observed Treatment Short-Course (DOTS) Centers. This diagnostic algorithm does not differentiate Mycobacterium tuberculosis complex (MTC) from nontuberculous mycobacteria (NTM). Between December 2008 and January 2009, consecutive patients diagnosed with TB were screened for inclusion at 10 DOTS centers in Ibadan, Nigeria. To verify Mycobacterium species in patients diagnosed, we cultured and identified mycobacterial isolates using PCR, line probe assay, and spoligotyping techniques. From 48 patients screened, 23 met the inclusion criteria for the study. All the 23 study patients had a positive culture. Overall, we identified 11/23 patients (48%) with MTC only, 9/23 (39%) with NTM only, and 3/23 (13%) with evidence of both MTC and NTM. Strains of MTC identified were Latin American Mediterranean (LAM) genotype (n = 12), M. africanum (n = 1), and the genotype family T (n = 1). Four M. avium-intracellulare-M. scrofulaceum complexes, one M. chelonae complex, one M. abscessus, and one M. intracellulare were identified. Our findings underscore the need to incorporate molecular techniques for more precise diagnosis of TB at DOTS centers to improve clinical outcomes and safe guard public health, particularly in TB endemic countries. PMID:27099795

  15. Nontuberculous Mycobacteria Isolated from Tuberculosis Suspects in Ibadan, Nigeria.

    PubMed

    Cadmus, Simeon Idowu; Diarra, Bassirou; Traore, Brehima; Maiga, Mamoudou; Siddiqui, Sophia; Tounkara, Anatole; Falodun, Olutayo; Lawal, Wole; Adewole, Isaac Folurunso; Murphy, Rob; van Soolingen, Dick; Taiwo, Babafemi

    2016-01-01

    In Nigeria, one of the highest tuberculosis (TB) burdened nations, sputum smear microscopy is routinely employed for TB diagnosis at Directly Observed Treatment Short-Course (DOTS) Centers. This diagnostic algorithm does not differentiate Mycobacterium tuberculosis complex (MTC) from nontuberculous mycobacteria (NTM). Between December 2008 and January 2009, consecutive patients diagnosed with TB were screened for inclusion at 10 DOTS centers in Ibadan, Nigeria. To verify Mycobacterium species in patients diagnosed, we cultured and identified mycobacterial isolates using PCR, line probe assay, and spoligotyping techniques. From 48 patients screened, 23 met the inclusion criteria for the study. All the 23 study patients had a positive culture. Overall, we identified 11/23 patients (48%) with MTC only, 9/23 (39%) with NTM only, and 3/23 (13%) with evidence of both MTC and NTM. Strains of MTC identified were Latin American Mediterranean (LAM) genotype (n = 12), M. africanum (n = 1), and the genotype family T (n = 1). Four M. avium-intracellulare-M. scrofulaceum complexes, one M. chelonae complex, one M. abscessus, and one M. intracellulare were identified. Our findings underscore the need to incorporate molecular techniques for more precise diagnosis of TB at DOTS centers to improve clinical outcomes and safe guard public health, particularly in TB endemic countries. PMID:27099795

  16. Biofilms of Pathogenic Nontuberculous Mycobacteria Targeted by New Therapeutic Approaches

    PubMed Central

    Aung, Thet Tun; Yam, Joey Kuok Hoong; Lin, Shuimu; Salleh, Shuhaida Mohamed; Givskov, Michael; Liu, Shouping; Lwin, Nyein Chan

    2015-01-01

    Microbial infections of the cornea are potentially devastating and can result in permanent visual loss or require vision-rescuing surgery. In recent years, there has been an increasing number of reports on nontuberculous mycobacterial infections of the cornea. Challenges to the management of nontuberculous mycobacterial keratitis include delayed laboratory detection, low index of clinical suspicion, poor drug penetration, slow response to therapy, and prolonged use of antibiotic combinations. The ability of nontuberculous mycobacteria to evade the host immune response and the ability to adhere and to form biofilms on biological and synthetic substrates contribute to the issue. Therefore, there is an urgent need for new antimicrobial compounds that can overcome these problems. In this study, we evaluated the biofilm architectures for Mycobacterium chelonae and Mycobacterium fortuitum in dynamic flow cell chamber and 8-well chamber slide models. Our results showed that mycobacterial biofilms were quite resistant to conventional antibiotics. However, DNase treatment could be used to overcome biofilm resistance. Moreover, we successfully evaluated a new antimicrobial compound (AM-228) that was effective not only for planktonic mycobacterial cells but also for biofilm treatment and was compared favorably with the most successful “fourth-generation” fluoroquinolone, gatifloxacin. Finally, a new treatment strategy emerged: a combination of DNase with an antibiotic was more effective than an antibiotic alone. PMID:26459903

  17. Review: Environmental mycobacteria as a cause of human infection.

    PubMed

    Halstrom, Samuel; Price, Patricia; Thomson, Rachel

    2015-06-01

    Pulmonary infections with nontuberculous mycobacteria (NTM) are recognized as a problem in immunodeficient individuals and are increasingly common in older people with no known immune defects. NTM are found in soil and water, but factors influencing transmission from the environment to humans are mostly unknown. Studies of the epidemiology of NTM disease have matched some clinical isolates of NTM with isolates from the patient's local environment. Definitive matching requires strain level differentiation based on molecular analyses, including partial sequencing, PCR-restriction fragment length polymorphism (RFLP) analysis, random amplified polymorphic DNA (RAPD) PCR, repetitive element (rep-) PCR and pulsed field gel electrophoresis (PFGE) of large restriction fragments. These approaches have identified hospital and residential showers and faucets, hot-tubs and garden soil as sources of transmissible pathogenic NTM. However, gaps exist in the literature, with many clinical isolates remaining unidentified within environments that have been tested, and few studies investigating NTM transmission in developing countries. To understand the environmental reservoirs and transmission routes of pathogenic NTM, different environments, countries and climates must be investigated.

  18. Nontuberculous Mycobacteria Isolated from Tuberculosis Suspects in Ibadan, Nigeria.

    PubMed

    Cadmus, Simeon Idowu; Diarra, Bassirou; Traore, Brehima; Maiga, Mamoudou; Siddiqui, Sophia; Tounkara, Anatole; Falodun, Olutayo; Lawal, Wole; Adewole, Isaac Folurunso; Murphy, Rob; van Soolingen, Dick; Taiwo, Babafemi

    2016-01-01

    In Nigeria, one of the highest tuberculosis (TB) burdened nations, sputum smear microscopy is routinely employed for TB diagnosis at Directly Observed Treatment Short-Course (DOTS) Centers. This diagnostic algorithm does not differentiate Mycobacterium tuberculosis complex (MTC) from nontuberculous mycobacteria (NTM). Between December 2008 and January 2009, consecutive patients diagnosed with TB were screened for inclusion at 10 DOTS centers in Ibadan, Nigeria. To verify Mycobacterium species in patients diagnosed, we cultured and identified mycobacterial isolates using PCR, line probe assay, and spoligotyping techniques. From 48 patients screened, 23 met the inclusion criteria for the study. All the 23 study patients had a positive culture. Overall, we identified 11/23 patients (48%) with MTC only, 9/23 (39%) with NTM only, and 3/23 (13%) with evidence of both MTC and NTM. Strains of MTC identified were Latin American Mediterranean (LAM) genotype (n = 12), M. africanum (n = 1), and the genotype family T (n = 1). Four M. avium-intracellulare-M. scrofulaceum complexes, one M. chelonae complex, one M. abscessus, and one M. intracellulare were identified. Our findings underscore the need to incorporate molecular techniques for more precise diagnosis of TB at DOTS centers to improve clinical outcomes and safe guard public health, particularly in TB endemic countries.

  19. First evidence of amoebae-mycobacteria association in drinking water network.

    PubMed

    Delafont, Vincent; Mougari, Faïza; Cambau, Emmanuelle; Joyeux, Michel; Bouchon, Didier; Héchard, Yann; Moulin, Laurent

    2014-10-21

    Free-living amoebae are protozoa ubiquitously found in water systems. They mainly feed on bacteria by phagocytosis, but some bacterial species are able to resist or even escape this lethal process. Among these amoeba resistant bacteria are numerous members of the genus Mycobacterium. Nontuberculous Mycobacteria (NTM) are opportunistic pathogens that share the same ecological niches as amoebae. While several studies have demonstrated the ability of these bacteria to colonise and persist within drinking water networks, there is also strong suspicion that mycobacteria could use amoebae as a vehicle for protection and even replication. We investigated here the presence of NTM and FLA on a drinking water network during an all year round sampling campaign. We observed that 87.6% of recovered amoebal cultures carried high numbers of NTM. Identification of these amoeba and mycobacteria strains indicated that the main genera found in drinking water networks, that is, Acanthamoeba, Vermamoeba, Echinamoeba, and Protacanthamoeba are able to carry and likely to allow replication of several environmental and potentially pathogenic mycobacteria including M. llatzerense and M. chelonae. Direct Sanger sequencing as well as pyrosequencing of environmental isolates demonstrated the frequent association of mycobacteria and FLA, as they are part of the most represented genera composing amoebae's microbiome. This is the first time that an association between FLA and NTM is observed in water networks, highlighting the importance of FLA in the ecology of NTM.

  20. First evidence of amoebae-mycobacteria association in drinking water network.

    PubMed

    Delafont, Vincent; Mougari, Faïza; Cambau, Emmanuelle; Joyeux, Michel; Bouchon, Didier; Héchard, Yann; Moulin, Laurent

    2014-10-21

    Free-living amoebae are protozoa ubiquitously found in water systems. They mainly feed on bacteria by phagocytosis, but some bacterial species are able to resist or even escape this lethal process. Among these amoeba resistant bacteria are numerous members of the genus Mycobacterium. Nontuberculous Mycobacteria (NTM) are opportunistic pathogens that share the same ecological niches as amoebae. While several studies have demonstrated the ability of these bacteria to colonise and persist within drinking water networks, there is also strong suspicion that mycobacteria could use amoebae as a vehicle for protection and even replication. We investigated here the presence of NTM and FLA on a drinking water network during an all year round sampling campaign. We observed that 87.6% of recovered amoebal cultures carried high numbers of NTM. Identification of these amoeba and mycobacteria strains indicated that the main genera found in drinking water networks, that is, Acanthamoeba, Vermamoeba, Echinamoeba, and Protacanthamoeba are able to carry and likely to allow replication of several environmental and potentially pathogenic mycobacteria including M. llatzerense and M. chelonae. Direct Sanger sequencing as well as pyrosequencing of environmental isolates demonstrated the frequent association of mycobacteria and FLA, as they are part of the most represented genera composing amoebae's microbiome. This is the first time that an association between FLA and NTM is observed in water networks, highlighting the importance of FLA in the ecology of NTM. PMID:25247827

  1. Disinfective process of strongly acidic electrolyzed product of sodium chloride solution against Mycobacteria.

    PubMed

    Yamamoto, Tomoyo Matsushita; Nakano, Takashi; Yamaguchi, Masaki; Shimizu, Mitsuhide; Wu, Hong; Aoki, Hiroaki; Ota, Rie; Kobayashi, Toyohide; Sano, Kouichi

    2012-12-01

    Electrolyzed acid water (EAW) has been studied for its disinfective potential against pathogenic microbes; however, the bactericidal process against Mycobacteria has not been clearly presented. In this study, to clarify the disinfective process against Mycobacteria, EAW-treated bacteria were examined against laboratory strains of Mycobacterium bovis (M. bovis), Mycobacterium smegmatis (M. smegmatis), and Mycobacterium terrae (M. terrae) by recovery culture and observation of morphology, enzymatic assay, and the detection of DNA. All experiments were performed with the use of EAW containing 30 ppm free chlorine that kills Mycobacteria, including three pathogenic clinical isolates of Mycobacterium tuberculosis (M. tuberculosis) and six isolates of other Mycobacteria, within 5 min. In morphology, the bacterial surface became rough, and a longitudinal concavity-like structure appeared. The intrabacterial enzyme of EAW-contacted bacteria was inactivated, but chromosomal DNA was not totally denatured. These results suggest that the bactericidal effect of EAW against Mycobacteria occurs by degradation of the cell wall, followed by denaturation of cytoplasmic proteins, but degeneration of the nucleic acid is not always necessary.

  2. Serological typing of mycobacteria for tracing possible sources of avian mycobacterial infections in man*

    PubMed Central

    Kubín, M.; Matušková, E.

    1968-01-01

    Avian mycobacteria represent a potential danger to the human population in areas where effective control of tuberculosis has been achieved, but where tuberculosis is still present in poultry. During the period 1957-67, a total of 44 cases of pulmonary and non-pulmonary disease in man caused by avian mycobacteria were recorded in Czechoslovakia. The source of infection was reliably established in only a small number of cases. The strains of bacteria isolated were, therefore, subjected to serological analysis using Schaefer's method of direct agglutination of bacterial suspensions by type-specific rabbit antisera. This procedure made it possible to differentiate true avian mycobacteria (serotypes I and II) from Runyon group III nonchromogens. The majority of the cultures isolated from man, and also a large proportion of those from cattle and swine, consisted of serotypes I and II, which are those of Mycobacterium avium. The possibility of classifying avian and atypical mycobacteria by means of agglutination procedures represents a valuable tool in the study of the epidemiology of mycobacterial diseases. Evidence was presented which indicated that, in Czechoslovakia, patients with tuberculosis due to avian mycobacteria acquire their infection mainly from animal sources. PMID:4980761

  3. Disinfective process of strongly acidic electrolyzed product of sodium chloride solution against Mycobacteria.

    PubMed

    Yamamoto, Tomoyo Matsushita; Nakano, Takashi; Yamaguchi, Masaki; Shimizu, Mitsuhide; Wu, Hong; Aoki, Hiroaki; Ota, Rie; Kobayashi, Toyohide; Sano, Kouichi

    2012-12-01

    Electrolyzed acid water (EAW) has been studied for its disinfective potential against pathogenic microbes; however, the bactericidal process against Mycobacteria has not been clearly presented. In this study, to clarify the disinfective process against Mycobacteria, EAW-treated bacteria were examined against laboratory strains of Mycobacterium bovis (M. bovis), Mycobacterium smegmatis (M. smegmatis), and Mycobacterium terrae (M. terrae) by recovery culture and observation of morphology, enzymatic assay, and the detection of DNA. All experiments were performed with the use of EAW containing 30 ppm free chlorine that kills Mycobacteria, including three pathogenic clinical isolates of Mycobacterium tuberculosis (M. tuberculosis) and six isolates of other Mycobacteria, within 5 min. In morphology, the bacterial surface became rough, and a longitudinal concavity-like structure appeared. The intrabacterial enzyme of EAW-contacted bacteria was inactivated, but chromosomal DNA was not totally denatured. These results suggest that the bactericidal effect of EAW against Mycobacteria occurs by degradation of the cell wall, followed by denaturation of cytoplasmic proteins, but degeneration of the nucleic acid is not always necessary. PMID:23224598

  4. Multidrug-resistant nontuberculous mycobacteria isolated from cystic fibrosis patients.

    PubMed

    Cândido, Pedro Henrique Campanini; Nunes, Luciana de Souza; Marques, Elizabeth Andrade; Folescu, Tânia Wrobel; Coelho, Fábrice Santana; de Moura, Vinicius Calado Nogueira; da Silva, Marlei Gomes; Gomes, Karen Machado; Lourenço, Maria Cristina da Silva; Aguiar, Fábio Silva; Chitolina, Fernanda; Armstrong, Derek T; Leão, Sylvia Cardoso; Neves, Felipe Piedade Gonçalves; Mello, Fernanda Carvalho de Queiroz; Duarte, Rafael Silva

    2014-08-01

    Worldwide, nontuberculous mycobacteria (NTM) have become emergent pathogens of pulmonary infections in cystic fibrosis (CF) patients, with an estimated prevalence ranging from 5 to 20%. This work investigated the presence of NTM in sputum samples of 129 CF patients (2 to 18 years old) submitted to longitudinal clinical supervision at a regional reference center in Rio de Janeiro, Brazil. From June 2009 to March 2012, 36 NTM isolates recovered from 10 (7.75%) out of 129 children were obtained. Molecular identification of NTM was performed by using PCR restriction analysis targeting the hsp65 gene (PRA-hsp65) and sequencing of the rpoB gene, and susceptibility tests were performed that followed Clinical and Laboratory Standards Institute recommendations. For evaluating the genotypic diversity, pulsed-field gel electrophoresis (PFGE) and/or enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR) was performed. The species identified were Mycobacterium abscessus subsp. bolletii (n = 24), M. abscessus subsp. abscessus (n = 6), Mycobacterium fortuitum (n = 3), Mycobacterium marseillense (n = 2), and Mycobacterium timonense (n = 1). Most of the isolates presented resistance to five or more of the antimicrobials tested. Typing profiles were mainly patient specific. The PFGE profiles indicated the presence of two clonal groups for M. abscessus subsp. abscessus and five clonal groups for M. abscesssus subsp. bolletii, with just one clone detected in two patients. Given the observed multidrug resistance patterns and the possibility of transmission between patients, we suggest the implementation of continuous and routine investigation of NTM infection or colonization in CF patients, including countries with a high burden of tuberculosis disease. PMID:24920766

  5. Mycobacteria and other environmental organisms as immunomodulators for immunoregulatory disorders.

    PubMed

    Rook, G A W; Adams, V; Hunt, J; Palmer, R; Martinelli, R; Brunet, L Rosa

    2004-02-01

    In the rich, developed parts of the world there has been a steady and simultaneous increase in at least three groups of disease: (1) allergies, (2) inflammatory bowel diseases (IBD; e.g. Crohn's disease and ulcerative colitis) and (3) autoimmunity (e.g. type 1 diabetes and multiple sclerosis). Because the medical world is so compartmentalised it was some time before the connection between these increases was noticed and understood. There is now evidence that the simultaneous increase in these diseases of immunodysregulation is at least partly attributable to malfunction of regulatory T cells (Treg). This paper provides an overview of relevant work in each of these fields of medicine (though with emphasis on the allergic disorders), and concludes that the increasing failure of Treg is a consequence of diminished exposure to certain micro-organisms that are "old friends", because of their continuous presence throughout mammalian evolution. These organisms, which include saprophytic mycobacteria, helminths and lactobacilli, are recognised by the innate immune system as harmless, and as adjuvants for Treg induction. Polymorphisms of components of the innate immune system such as TLR2 and NOD2 appear to define subsets of the population that will develop immunoregulatory disorders when living in the modern environment. A further role of the "old friends" and of the Treg that they induce might be to maintain the levels of regulatory IL-10 secreting macrophages and antigen-presenting cells, which are depleted in asthma and Crohn's disease. These concepts are leading to novel therapies based on harmless organisms or their components. Phase I/II clinical trials have yielded some statistically significant results, and phase II trials are in progress. PMID:15007629

  6. The Use of High Performance Liquid Chromatography to Speciate and Characterize the Epidemiology of Mycobacteria

    PubMed Central

    Jeong, Joseph; Kim, Sung-Ryul; Lee, Seon Ho; Lim, Ji-Hun; Choi, Jung In; Park, Jae Sun; Chang, Chulhun L.; Choi, Jun Yong; Richman, Douglas D.; Smith, Davey M.

    2013-01-01

    Objective We evaluated high-performance liquid chromatography (HPLC) for species identification of mycobacteria from various clinical specimens in an urban hospital in South Korea between January 2005 and December 2009. Methods In the study period 24,774 cultures were completed, yielding the 3215 clinical isolates cultivated for mycobacteria and positive cultures that had mycolic acid investigated by HPLC. For species identification, we compared HPLC patterns of clinical isolates with 33 standard Mycobacterium species. Results There were 3 different HPLC groups with single, double, and triple-cluster patterns representing 9, 20, and 4 mycobacterial species, respectively. Species identification rates of HPLC for Mycobacterium tuberculosis and nontuberculous mycobacteria (NTM) were found to be 100% and 95.6%, respectively. Among mycobacterial isolates, 12.1% were NTM-positive. There were 20 different NTM species with frequencies of 0.3%~15.5%. Conclusion The HPLC method was highly sensitive identifying NTM isolated from clinical specimens. PMID:24443588

  7. Peptide Targeting of an Antibiotic Prodrug toward Phagosome-Entrapped Mycobacteria.

    PubMed

    Pereira, Mark P; Shi, Julie; Kelley, Shana O

    2015-12-11

    Mycobacterial infections are difficult to treat due to the bacterium's slow growth, ability to reside in intracellular compartments within macrophages, and resistance mechanisms that limit the effectiveness of conventional antibiotics. Developing antibiotics that overcome these challenges is therefore critical to providing a pipeline of effective antimicrobial agents. Here, we describe the synthesis and testing of a unique peptide-drug conjugate that exhibits high levels of antimicrobial activity against M. smegmatis and M. tuberculosis as well as clearance of intracellular mycobacteria from cultured macrophages. Using an engineered peptide sequence, we deliver a potent DHFR inhibitor and target the intracellular phagosomes where mycobacteria reside and also incorporate a β-lactamase-cleavable cephalosporin linker to enhance the targeting of quiescent intracellular β-lactam-resistant mycobacteria. By using this type of prodrug approach to target intracellular mycobacterial infections, the emergence of antibacterial resistance mechanisms could be minimized. PMID:27623056

  8. A Novel Multiplex Real-Time PCR for the Identification of Mycobacteria Associated with Zoonotic Tuberculosis

    PubMed Central

    Reddington, Kate; O'Grady, Justin; Dorai-Raj, Siobhan; Niemann, Stefan; van Soolingen, Dick; Barry, Thomas

    2011-01-01

    Background Tuberculosis (TB) is the leading cause of death worldwide from a single infectious agent. An ability to detect the Mycobacterium tuberculosis complex (MTC) in clinical material while simultaneously differentiating its members is considered important. This allows for the gathering of epidemiological information pertaining to the prevalence, transmission and geographical distribution of the MTC, including those MTC members associated with zoonotic TB infection in humans. Also differentiating between members of the MTC provides the clinician with inherent MTC specific drug susceptibility profiles to guide appropriate chemotherapy. Methodology/Principal Findings The aim of this study was to develop a multiplex real-time PCR assay using novel molecular targets to identify and differentiate between the phylogenetically closely related M. bovis, M. bovis BCG and M. caprae. The lpqT gene was explored for the collective identification of M. bovis, M. bovis BCG and M. caprae, the lepA gene was targeted for the specific identification of M. caprae and a Region of Difference 1 (RD1) assay was incorporated in the test to differentiate M. bovis BCG. The multiplex real-time PCR assay was evaluated on 133 bacterial strains and was determined to be 100% specific for the members of the MTC targeted. Conclusions/Significance The multiplex real-time PCR assay developed in this study is the first assay described for the identification and simultaneous differentiation of M. bovis, M. bovis BCG and M. caprae in one internally controlled reaction. Future validation of this multiplex assay should demonstrate its potential in the rapid and accurate diagnosis of TB caused by these three mycobacteria. Furthermore, the developed assay may be used in conjunction with a recently described multiplex real-time PCR assay for identification of the MTC and simultaneous differentiation of M. tuberculosis, M. canettii resulting in an ability to differentiate five of the eight members of the

  9. Identification of Clinical Isolates of Mycobacteria with Gas-Liquid Chromatography Alone

    PubMed Central

    Tisdall, Philip A.; Roberts, Glenn D.; Anhalt, John P.

    1979-01-01

    Identification of 18 mycobacterial species was performed by analysis of profiles obtained by using gas-liquid chromatography. Organisms were saponified in methanolic NaOH, and the reaction mixture was treated with BF3 in methanol and extracted with a hexane-chloroform mixture. An identification scheme was developed from 128 stock strains and tested against a collection of 79 clinical isolates. By using gas-liquid chromatographic profiles alone, 58% of specimens were correctly identified to species level, and an additional 41% were correctly identified to a group of two or three organisms. Use in a clinical laboratory over a 2-month period proved chromatography to be as accurate as and more rapid than concurrent biochemical testing. Of 81 isolates tested, 64% were identified to species level by chromatography alone. An additional 35% were differentiated to the same groups of two or three organisms as found in our analysis of stock strains. These groups consisted of: Mycobacterium tuberculosis, M. bovis, and M. xenopi; M. avium complex, M. gastri, and M. scrofulaceum; or M. fortuitum and M. chelonei. Identification to species level from these groups could usually be done by colonial morphology alone and could always be done by the addition of one selected biochemical test. This study demonstrated the practical application of gas-liquid chromatography in the identification of mycobacteria in a clinical laboratory. In particular, all strains of M. gordonae and M. kansasii were identified to species level. M. tuberculosis was definitively identified in 85% of cases. When it could not be definitely identified, the only alternatives were M. bovis and M. xenopi, both of which are rare causes of infection. PMID:118984

  10. In vitro antimicrobial efficacy of a silver-containing wound dressing against mycobacteria associated with atypical skin ulcers.

    PubMed

    Bowler, Philip G; Welsby, Sarah; Towers, Victoria

    2013-08-01

    Mycobacterium ulcerans, the etiological agent in Buruli and related ulcers, is a major threat to public health in many tropical countries. Recommended treatment that is accessible and affordable for affected individuals includes surgical debridement and combination antibiotics. The potential benefits in the use of antimicrobial wound dressings has not been demonstrated to date, and consequently the efficacy of a silver-containing absorbent dressing was investigated against a pathogenic wound mycobacterium using stringent in vitro models. The in vitro models were designed to simulate a variety of challenging wound conditions. Mycobacterium fortuitum was used as a fast-growing surrogate for M. ulcerans, a physiologically similar but slower-growing and more significant wound pathogen. Collectively, the studies showed that the silver-containing dressing was bactericidal against M. fortuitum, it maintained killing effect over a prolonged period (7 days) under conditions simulating excessive exudate, and killed an average of 100% of the bacterial population inoculated directly beneath the dressing in a simulated, colonized, shallow wound model. Based on the in vitro data generated in the current research, use of the silver-containing dressing as part of a protocol-of-care in the management of Buruli and related ulcers may help to alleviate wound infection caused by pathogenic mycobacteria, improve quality of life, and provide infection protection in endemic and at-risk regions. .

  11. PCR assay based on DNA coding for 16S rRNA for detection and identification of mycobacteria in clinical samples.

    PubMed Central

    Kox, L F; van Leeuwen, J; Knijper, S; Jansen, H M; Kolk, A H

    1995-01-01

    A PCR and a reverse cross blot hybridization assay were developed for the detection and identification of mycobacteria in clinical samples. The PCR amplifies a part of the DNA coding for 16S rRNA with a set of primers that is specific for the genus Mycobacterium and that flanks species-specific sequences within the genes coding for 16S rRNA. The PCR product is analyzed in a reverse cross blot hybridization assay with probes specific for M. tuberculosis complex (pTub1), M. avium (pAvi3), M. intracellulare (pInt5 and pInt7), M. kansasii complex-M. scrofulaceum complex (pKan1), M. xenopi (pXen1), M. fortuitum (pFor1), M. smegmatis (pSme1), and Mycobacterium spp. (pMyc5a). The PCR assay can detect 10 fg of DNA, the equivalent of two mycobacteria. The specificities of the probes were tested with 108 mycobacterial strains (33 species) and 31 nonmycobacterial strains (of 17 genera). The probes pAvi3, pInt5, pInt7, pKan1, pXen1, and pMyc5a were specific. With probes pTub1, pFor1, and pSme1, slight cross hybridization occurred. However, the mycobacterial strains from which the cross-hybridizing PCR products were derived belonged to nonpathogenic or nonopportunistic species which do not occur in clinical samples. The test was used on 31 different clinical specimens obtained from patients suspected of having mycobacterial disease, including a patient with a double mycobacterial infection. The samples included sputum, bronchoalveolar lavage, tissue biopsy samples, cerebrospinal fluid, pus, peritoneal fluid, pleural fluid, and blood. The results of the PCR assay agreed with those of conventional identification methods or with clinical data, showing that the test can be used for the direct and rapid detection and identification of mycobacteria in clinical samples. PMID:8586707

  12. Characterization of mycobacteria from a major Brazilian outbreak suggests that revision of the taxonomic status of members of the Mycobacterium chelonae-M. abscessus group is needed.

    PubMed

    Leao, Sylvia Cardoso; Tortoli, Enrico; Viana-Niero, Cristina; Ueki, Suely Yoko Mizuka; Lima, Karla Valeria Batista; Lopes, Maria Luiza; Yubero, Jesus; Menendez, Maria Carmen; Garcia, Maria Jesus

    2009-09-01

    An outbreak of postsurgical infections caused by rapidly growing mycobacteria has been ongoing in Brazil since 2004. The degrees of similarity of the rpoB and hsp65 sequences from the clinical isolates and the corresponding sequences from both the Mycobacterium massiliense and the M. bolletii type strains were above the accepted limit for interspecies variability, leading to conflicting identification results. Therefore, an extensive characterization of members of the M. chelonae-M. abscessus group was carried out. The M. abscessus, M. chelonae, M. immunogenum, M. massiliense, and M. bolletii type strains and a subset of clinical isolates were analyzed by biochemical tests, high-performance liquid chromatography, drug susceptibility testing, PCR-restriction enzyme analysis of hsp65 (PRA-hsp65), rpoB, and hsp65 gene sequencing and analysis of phylogenetic trees, DNA-DNA hybridization (DDH), and restriction fragment length polymorphism (RFLP) analysis of the 16S rRNA gene (RFLP-16S rRNA). The clinical isolates and the M. abscessus, M. massiliense, and M. bolletii type strains could not be separated by phenotypic tests and were grouped in the phylogenetic trees obtained. The results of DDH also confirmed the >70% relatedness of the clinical isolates and the M. abscessus, M. massiliense, and M. bolletii type strains; and indistinguishable RFLP-16S rRNA patterns were obtained. On the contrary, the separation of clinical isolates and the M. abscessus, M. massiliense, and M. bolletii type strains from M. chelonae and M. immunogenum was supported by the results of PRA-hsp65, DDH, and RFLP-16S rRNA and by the rpoB and hsp65 phylogenetic trees. Taken together, these results led to the proposition that M. abscessus, M. massiliense, and M. bolletii represent a single species, that of M. abscessus. Two subspecies are also proposed, M. abscessus subsp. abscessus and M. abscessus subsp. massiliense, and these two subspecies can be distinguished by two different PRA-hsp65 patterns

  13. How Does Your Garlic Grow?

    ERIC Educational Resources Information Center

    Shimabukuro, Mary A.; Fearing, Vickie

    1993-01-01

    Garlic is an ideal plant for the elementary classroom. It grows rapidly in water without aeration for several weeks and remains relatively free of microbial contamination. Simple experiments with garlic purchased at grocery stores can illustrate various aspects of plant growth. (PR)

  14. Growing and Growing: Promoting Functional Thinking with Geometric Growing Patterns

    ERIC Educational Resources Information Center

    Markworth, Kimberly A.

    2010-01-01

    Design research methodology is used in this study to develop an empirically-substantiated instruction theory about students' development of functional thinking in the context of geometric growing patterns. The two research questions are: (1) How does students' functional thinking develop in the context of geometric growing patterns? (2) What are…

  15. Nonlinear growing neutrino cosmology

    NASA Astrophysics Data System (ADS)

    Ayaita, Youness; Baldi, Marco; Führer, Florian; Puchwein, Ewald; Wetterich, Christof

    2016-03-01

    The energy scale of dark energy, ˜2 ×10-3 eV , is a long way off compared to all known fundamental scales—except for the neutrino masses. If dark energy is dynamical and couples to neutrinos, this is no longer a coincidence. The time at which dark energy starts to behave as an effective cosmological constant can be linked to the time at which the cosmic neutrinos become nonrelativistic. This naturally places the onset of the Universe's accelerated expansion in recent cosmic history, addressing the why-now problem of dark energy. We show that these mechanisms indeed work in the growing neutrino quintessence model—even if the fully nonlinear structure formation and backreaction are taken into account, which were previously suspected of spoiling the cosmological evolution. The attractive force between neutrinos arising from their coupling to dark energy grows as large as 106 times the gravitational strength. This induces very rapid dynamics of neutrino fluctuations which are nonlinear at redshift z ≈2 . Nevertheless, a nonlinear stabilization phenomenon ensures only mildly nonlinear oscillating neutrino overdensities with a large-scale gravitational potential substantially smaller than that of cold dark matter perturbations. Depending on model parameters, the signals of large-scale neutrino lumps may render the cosmic neutrino background observable.

  16. Mycobacterium abscessus in Healthcare Settings

    MedlinePlus

    ... of environmental mycobacteria and is found in water, soil, and dust. It has been known to contaminate ... rapidly growing mycobacteria and is found in water, soil, and dust. It has been known to contaminate ...

  17. Modeling Human Exposure Risk to Nontuberculous Mycobacteria in Central North Carolina

    EPA Science Inventory

    Nontuberculous mycobacteria (NTM) are a broad group of soil-and water-borne bacteria. Some species are pathogenic and may cause serious infections in the lungs, soft tissues, bones and skin. Infections in humans are associated with environmental exposures to contaminated soil, ae...

  18. Exosomal Hsp70 Induces a Pro-Inflammatory Response to Foreign Particles Including Mycobacteria

    PubMed Central

    Anand, Paras K.; Anand, Ellis; Bleck, Christopher K. E.; Anes, Elsa; Griffiths, Gareth

    2010-01-01

    Background Exosomes are endosome-derived vesicles that are released when multi-vesicular bodies (MVBs) fuse with the plasma membrane. Exosomes released from mycobacteria-infected cells have recently been shown to be pro-inflammatory. A prominent host molecule that is found within these exosomes is Hsp70, a member of the heat-shock family of proteins. Methodology/Principal Findings We first characterized the exosomes purified from control and mycobacteria-infected cells. We found that relative to uninfected cells, macrophages infected with M. smegmatis and M. avium release more exosomes and the exosomes they released had more Hsp70 on their surface. Both exosomes and exogenous Hsp70 treatment of macrophages led to NF-κB activation and TNFα release in uninfected macrophages; Hsp70 levels were elevated in mycobacteria-infected cells. Macrophage treatment with Hsp70 also led to increase in the phagocytosis and maturation of latex-bead phagosomes. Finally, Hsp70 pre-incubation of M. smegmatis- and M. avium-infected cells led to increased phago-lysosome fusion, as well as more killing of mycobacteria within macrophages. Conclusions/Significance Our results fit into an emerging concept whereby exosomes-containing Hsp70 are effective inducers of inflammation, also in response to mycobacterial infection. PMID:20405033

  19. Mild Nutrient Starvation Triggers the Development of a Small-Cell Survival Morphotype in Mycobacteria

    PubMed Central

    Wu, Mu-Lu; Gengenbacher, Martin; Dick, Thomas

    2016-01-01

    Mycobacteria, generally believed to be non-sporulating, are well known to survive shock starvation in saline for extended periods of time in a non-replicating state without any apparent morphological changes. Here, we uncover that mycobacteria can undergo cellular differentiation by exposing Mycobacterium smegmatis to mild starvation conditions. Traces of various carbon sources in saline triggered the development of a novel small resting cell (SMRC) morphotype. Development of SMRCs could also be observed for other mycobacteria, suggesting evolutionary conservation of this differentiation pathway. Fluorescence microscopic analyses showed that development of SMRCs progresses via septated, multi-nucleoided cell intermediates, which divide to generate mono-nucleoided SMRCs. Intriguingly, saline shock-starved large resting cells (LARCs), which did not show cell size or surface changes when observed by scanning electron microscopy, remodeled their internal structure to septated, multi-nucleoided cells, similar to the intermediates seen during differentiation to SMRCs. Our results suggest that mycobacteria harbor a starvation-induced differentiation program in which at first septated, multi-nucleoided cells are generated. Under zero-nutrient conditions bacteria terminate development at this stage as LARCs. In the presence of traces of a carbon source, these multi-nucleoided cells continue differentiation into mono-nucleoided SMRCs. Both SMRCs and LARCs exhibited extreme antibiotic tolerance. SMRCs showed increased long-term starvation survival, which was associated with the presence of lipid inclusion bodies. PMID:27379076

  20. HUMAN INFECTION WITH NONTUBERCULOUS MYCOBACTERIA SPP. IN KING COUNTY, WASHINGTON, 1999-2002

    EPA Science Inventory

    Human infection with nontuberculous Mycobacteria spp. in King County, Washington, 1999 - 2002
    E Hilborn, T Covert, M Yakrus, G Stelma, M Schmitt
    1) US Environmental Protection Agency, Office of Research and Development, National Health and Environmental Research Laboratory,...

  1. Isolation and identification of mycobacteria from soils at an illegal dumping site and landfills in Japan.

    PubMed

    Wang, Yan; Ogawa, Midori; Fukuda, Kazumasa; Miyamoto, Hiroshi; Taniguchi, Hatsumi

    2006-01-01

    In order to study the diversity and community of genus Mycobacterium in polluted soils, we tried to isolate mycobacteria from 11 soil samples collected from an illegal dumping site and 3 landfills in Japan. Using culture methods with or without Acanthamoeba culbertsoni, a total of 19 isolates of mycobacteria were obtained from 5 soil samples and 3 of them were isolated only by the co-culture method with the amoeba. Conventional biochemical tests and sequencing of the hsp65, rpoB, and 16S rRNA genes were performed for species identification of 17 of the 19 isolates. Among the 17 isolates, there was one isolate each of Mycobacterium vanbaalenii, Mycobacterium mageritense, Mycobacterium frederiksbergense, M. vanbaalenii or Mycobacterium austroafricanum, and Mycobacterium chubuense or Mycobacterium chlorophenolicum. The remaining 12 isolates could not be precisely identified at the species level. A phylogenic tree based on the hsp65 sequences indicated that 2 of the 12 isolates were novel species. In addition, 4 isolates were phylogenically close to species that degrade polycyclic aromatic hydrocarbons, which induce some cancers in humans. These results demonstrated that there were many hitherto-unreported mycobacteria in the polluted soils, and suggested that some mycobacteria might play roles in the natural attenuation and engineered bioremediation of contaminated sites with other microorganisms.

  2. Detection of untreated mycobacteria by using polymerase chain reaction and specific DNA probes.

    PubMed Central

    Fries, J W; Patel, R J; Piessens, W F; Wirth, D F

    1991-01-01

    A method for specific identification of mycobacteria by using the polymerase chain reaction on organisms taken from liquid cultures, frozen suspensions, or colonies grown on Lowenstein-Jensen slants is presented. This direct detection of mycobacterial organisms has important implications for strain typing and diagnosis. Images PMID:1761699

  3. Detection of nontuberculous mycobacteria from water buffalo raw milk in Brazil.

    PubMed

    Jordão Junior, C M; Lopes, F C M; David, S; Farache Filho, A; Leite, C Q F

    2009-09-01

    Milk is an important nutritional source to man and water buffalo raw milk is used to produce mozzarella cheese. Products from unpasteurized milk have been associated with certain infectious diseases and can carry pathogenic mycobacteria. Nontuberculous mycobacteria (NTM) are emerging pathogens causing opportunistic infections in humans and animals. The objectives of this study were to demonstrate the presence of mycobacteria in water buffaloes' milk and to determine their role as possible sources of NTM infections. In this study, raw milk samples from dairy water buffaloes (Bubalus bubalis) (N = 23) were decontaminated by Petroff method and inoculated on to Löwenstein-Jensen and Stonebrink medium. After confirming positive colonies for acid fast bacilli (AFB) by Ziehl-Neelsen technique, the isolated mycobacteria were identified by PCR-Restriction Enzyme Analysis (PRA) and mycolic acids analysis by thin-layer chromatography (TLC). Mycobacterium simiae (2 isolates), Mycobacterium kansasii (2 isolates), Mycobacterium flavescens (2 isolates), Mycobacterium gordonae (3 isolates) and Mycobacterium lentiflavum (1 isolate) were identified by these techniques. The isolation of opportunistic pathogens such as M. kansasii, M. simiae and M. lentiflavum from raw milk represent a risk for the consumers of mozzarella cheese made by this milk.

  4. Comparison of methods for the isolation of mycobacteria from water treatment plant sludge.

    PubMed

    Makovcova, Jitka; Babak, Vladimir; Slany, Michal; Slana, Iva

    2015-05-01

    Nontuberculous mycobacteria (NTM) are ubiquitous organisms in all natural ecosystems, including water environments. Several of these species are potential pathogens which affect human health. NTM most commonly cause pulmonary, skin or soft tissue infections. Primary sludge obtained from the water treatment plants of four drinking water reservoirs were subjected to analysis for mycobacteria. Five decontamination methods (5% oxalic acid, modified Petroff, HCl-NaOH, N-acetyl-L-cysteine-sodium hydroxide and 0.05% cetylpyridinium chloride), three growth media (Herrold's egg yolk medium with and without the antibiotic cocktail PANTA and Löwenstein-Jensen medium with sodium pyruvate) and three incubation temperatures (25, 30 and 37 °C) for isolation of mycobacteria were compared in the analysis of 18 sludge samples. To evaluate examined methods, the overall positive, negative, and contamination rate, and these rates in respect to localities are taken into account. Statistical analysis demonstrated that the best combination for the recovery of mycobacteria with the minimum number of contaminating microorganisms is 5% oxalic acid decontamination cultured on Herrold's egg yolk medium with the antibiotic cocktail PANTA at 25 °C. The least suitable is N-acetyl-L-cysteine-sodium hydroxide decontamination cultured on Löwenstein-Jensen medium with sodium pyruvate at 25 °C. From 18 sludge samples we isolated 27 mycobacterial species or groups; Mycobacterium algericum, M. arabiense, M. heraklionense, M. minnesotense, M. moriokaense, M. salmoniphilum and M. vulneris were isolated from the natural water environment for the first time. Because the natural water environment is the main source of potentially pathogenic mycobacteria for humans, it is important to direct particular focus to newly described mycobacterial species.

  5. Isolation and characterization of mycobacteria from striped bass Morone saxatilis from the Chesapeake Bay

    USGS Publications Warehouse

    Rhodes, M.W.; Kator, H.; Kaattari, I.; Gauthier, D.; Vogelbein, W.; Ottinger, C.A.

    2004-01-01

    Mycobacteriosis in striped bass Morone saxatilis of Chesapeake Bay, USA, was first diagnosed in 1997 based on the presence of granulomatous inflammation and acid-fast bacteria in skin and spleen. To confirm histopathology, bacteriological detection and identification of mycobacteria were begun using splenic tissue from fish with and without skin ulcerations. On the basis of initial studies using a variety of selective and nonselective media, decontamination, homogenization and incubation conditions, a simple and quantitative recovery method using aseptic necropsy of splenic tissue was developed. Optimal recovery was obtained by spread-plating homogenates on Middlebrook 7H10 agar with incubation for 3 mo at 23??C. Mycobacteria were recovered from 76% (n = 149/196) of fish examined. Mycobacterial densities exceeded 104 colony forming units??g tissue-1 in 38% of samples (n = 63/168) that were examined using a quantitative approach. The most frequently recovered mycobacterium, present in 57% (n = 109/192) of characterized samples, was the recently named new species Mycobacterium shottsii. Polyinfections of M. shottsii and other mycobacteria were observed in 25% of samples (n = 47/192) with densities of M. shottsii usually 1 or more orders of magnitude higher than co-isolate(s). Other mycobacteria recovered included isolates that, based on phenotypic traits, resembled M. interjectum, M. marinum, M. scrofulaceum, M. szulgai and M. triplex. M. marinum, commonly associated with fish mycobacteriosis and human disease, was recovered infrequently (3%, n = 6/192). The presence of multiple mycobacterial types occurring at high densities suggests that a variety of mycobacteria could be causative agents of mycobacteriosis in striped bass from the Chesapeake Bay. Striped bass is the major recreational fish species in the Chesapeake Bay, and the significance of the current epizootic to human health and the potential adverse effects on fish stocks are not known.

  6. A Flow Cytometry Method for Rapidly Assessing Mycobacterium tuberculosis Responses to Antibiotics with Different Modes of Action

    PubMed Central

    Hendon-Dunn, Charlotte Louise; Doris, Kathryn Sarah; Thomas, Stephen Richard; Allnutt, Jonathan Charles; Marriott, Alice Ann Neville; Hatch, Kim Alexandra; Watson, Robert James; Bottley, Graham; Marsh, Philip David; Taylor, Stephen Charles

    2016-01-01

    Current methods for assessing the drug susceptibility of Mycobacterium tuberculosis are lengthy and do not capture information about viable organisms that are not immediately culturable under standard laboratory conditions as a result of antibiotic exposure. We have developed a rapid dual-fluorescence flow cytometry method using markers for cell viability and death. We show that the fluorescent marker calcein violet with an acetoxy-methyl ester group (CV-AM) can differentiate between populations of M. tuberculosis growing at different rates, while Sytox green (SG) can differentiate between live and dead mycobacteria. M. tuberculosis was exposed to isoniazid or rifampin at different concentrations over time and either dual stained with CV-AM and SG and analyzed by flow cytometry or plated to determine the viability of the cells. Although similar trends in the loss of viability were observed when the results of flow cytometry and the plate counting methods were compared, there was a lack of correlation between these two approaches, as the flow cytometry analysis potentially captured information about cell populations that were unable to grow under standard conditions. The flow cytometry approach had an additional advantage in that it could provide insights into the mode of action of the drug: antibiotics targeting the cell wall gave a flow cytometry profile distinct from those inhibiting intracellular processes. This rapid drug susceptibility testing method could identify more effective antimycobacterials, provide information about their potential mode of action, and accelerate their progress to the clinic. PMID:26902767

  7. A Flow Cytometry Method for Rapidly Assessing Mycobacterium tuberculosis Responses to Antibiotics with Different Modes of Action.

    PubMed

    Hendon-Dunn, Charlotte Louise; Doris, Kathryn Sarah; Thomas, Stephen Richard; Allnutt, Jonathan Charles; Marriott, Alice Ann Neville; Hatch, Kim Alexandra; Watson, Robert James; Bottley, Graham; Marsh, Philip David; Taylor, Stephen Charles; Bacon, Joanna

    2016-07-01

    Current methods for assessing the drug susceptibility of Mycobacterium tuberculosis are lengthy and do not capture information about viable organisms that are not immediately culturable under standard laboratory conditions as a result of antibiotic exposure. We have developed a rapid dual-fluorescence flow cytometry method using markers for cell viability and death. We show that the fluorescent marker calcein violet with an acetoxy-methyl ester group (CV-AM) can differentiate between populations of M. tuberculosis growing at different rates, while Sytox green (SG) can differentiate between live and dead mycobacteria. M. tuberculosis was exposed to isoniazid or rifampin at different concentrations over time and either dual stained with CV-AM and SG and analyzed by flow cytometry or plated to determine the viability of the cells. Although similar trends in the loss of viability were observed when the results of flow cytometry and the plate counting methods were compared, there was a lack of correlation between these two approaches, as the flow cytometry analysis potentially captured information about cell populations that were unable to grow under standard conditions. The flow cytometry approach had an additional advantage in that it could provide insights into the mode of action of the drug: antibiotics targeting the cell wall gave a flow cytometry profile distinct from those inhibiting intracellular processes. This rapid drug susceptibility testing method could identify more effective antimycobacterials, provide information about their potential mode of action, and accelerate their progress to the clinic.

  8. Pulmonary Infection with Hypervirulent Mycobacteria Reveals a Crucial Role for the P2X7 Receptor in Aggressive Forms of Tuberculosis

    PubMed Central

    Amaral, Eduardo P.; Ribeiro, Simone C. M.; Lanes, Verônica R.; Almeida, Fabrício M.; de Andrade, Marcelle R. M.; Bomfim, Caio Cesar Barbosa; Salles, Érika M.; Bortoluci, Karina R.; Coutinho-Silva, Robson; Hirata, Mario H.; Alvarez, José M.; Lasunskaia, Elena B.; D'Império-Lima, Maria Regina

    2014-01-01

    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. PMID:24991816

  9. Counting Mycobacteria in Infected Human Cells and Mouse Tissue: A Comparison between qPCR and CFU

    PubMed Central

    Pathak, Sharad; Awuh, Jane A.; Leversen, Nils Anders; Flo, Trude H.; Åsjø, Birgitta

    2012-01-01

    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 (

  10. 16S rDNA-based probes for two polycyclic aromatic hydrocarbon (PAH)-degrading soil Mycobacteria

    SciTech Connect

    Govindaswami, M.; Feldhake, D.J.; Loper, J.C.

    1994-12-31

    PAHs are a class of widespread pollutants, some of which have been shown to be genotoxic, hence the fate of these compounds in the environment is of considerable interest. Research on the biodegradation of 4 and 5 ring PAHs has been limited by the general lack of microbial isolates or consortia which can completely degrade these toxicants. Heitkamp and Cerniglia have described an oxidative soil Mycobacterium-strain PYR-1 that metabolizes pyrene and fluoranthene more rapidly than the 2 and 3 ring naphthalene and phenanthrene; although some metabolites of benzo-(a)-pyrene (BaP) were detected, no mineralization of BaP was observed. In 1991 Grosser et al. reported the isolation of a Mycobacterium sp. which mineralizes pyrene and also causing some mineralization of BaP. Their study describes a comparative analysis of these two strains, which show very similar colony morphology, growth rate and yellow-orange pigmentation. Genetic differences were shown by DNA amplification fingerprinting (DAF) using two arbitrary GC-rich octanucleotide primers, and by sequence comparison of PCR amplified 16S rDNA, although both strains show similarity closest to that of the genus Mycobacteria. These 16S rDNA sequences are in use for the construction of strain-specific DNA probes to monitor the presence, survival and growth of these isolates in PAH-contaminated soils in studies of biodegradation.

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

    SciTech Connect

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

    1984-10-01

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

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

    PubMed

    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

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

    PubMed Central

    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

  14. Conserved Pro-Glu (PE) and Pro-Pro-Glu (PPE) Protein Domains Target LipY Lipases of Pathogenic Mycobacteria to the Cell Surface via the ESX-5 Pathway*

    PubMed Central

    Daleke, Maria H.; Cascioferro, Alessandro; de Punder, Karin; Ummels, Roy; Abdallah, Abdallah M.; van der Wel, Nicole; Peters, Peter J.; Luirink, Joen; Manganelli, Riccardo; Bitter, Wilbert

    2011-01-01

    The type VII secretion system ESX-5 is a major pathway for export of PE and PPE proteins in pathogenic mycobacteria. These mycobacteria-specific protein families are characterized by conserved N-terminal domains of 100 and 180 amino acids, which contain the proline-glutamic acid (PE) and proline-proline-glutamic acid (PPE) motifs after which they are named. Here we investigated secretion of the triacylglycerol lipase LipY, which in fast-growing mycobacteria contains a signal sequence, but in slow-growing species appears to have replaced the signal peptide with a PE or PPE domain. Selected LipY homologues were expressed in wild-type Mycobacterium marinum and its corresponding ESX-5 mutant, and localization of the proteins was investigated by immunoblotting and electron microscopy. Our study shows that Mycobacterium tuberculosis PE-LipY (LipYtub) and M. marinum PPE-LipY (LipYmar) are both secreted to the bacterial surface in an ESX-5-dependent fashion. After transport, the PE/PPE domains are removed by proteolytic cleavage. In contrast, Mycobacterium gilvum LipY, which has a signal sequence, is not transported to the cell surface. Furthermore, we show that LipYtub and LipYmar require their respective PE and PPE domains for ESX-5-dependent secretion. The role of the PE domain in ESX-5 secretion was confirmed in a whole cell lipase assay, in which wild-type bacteria expressing full-length LipYtub, but not LipYtub lacking its PE domain, were shown to hydrolyze extracellular lipids. In conclusion, both PE and PPE domains contain a signal required for secretion of LipY by the ESX-5 system, and these domains are proteolytically removed upon translocation. PMID:21471225

  15. Mycobacteria are hidden endophytes in the shoots of rock plant [Pogonatherum paniceum (Lam.) Hack.] (Poaceae).

    PubMed

    Koskimäki, Janne J; Hankala, Elina; Suorsa, Marja; Nylund, Sannakajsa; Pirttilä, Anna Maria

    2010-08-01

    A mycobacterium was isolated from micropropagated Pogonatherum paniceum and identified as a close relative of Mycobacterium cookii. The endophyte diversity in the shoots of potted and micropropagated P. paniceum plants was studied by culture-independent techniques. Group- and strain-specific PCR demonstrated that the P. paniceum plants harboured the isolated Mycobacterium strain as a minority. Altogether 101 clones of the PCR products were sequenced. The shoots of potted P. paniceum plants harboured unculturable endophytes in the families Phyllobacteriaceae, Hyphomicrobiaceae, Sphingobacteriaceae, Enterobacteriaceae, Alcaligenaceae and Mycobacteriaceae. Among the unculturable Mycobacteriaceae strains related to Mycobacterium chubuense, M. poriferae, M. obuense, M. fortuitum, M. neoaurum, M. diernhoferi, M. intracellulare and M. cookii were identified. Three unique sequences that clustered with M. llatzarense and M. mucogenicum were identified in micropropagated plants. According to the results, the shoots and micropropagated tissues of rock plant are inhabited by mycobacteria, which should stimulate further studies on the diversity of unculturable mycobacteria in edible crop plants.

  16. Evaluation of a new biphasic culture system for the recovery of mycobacteria.

    PubMed

    Giger, T; Burkardt, H J

    1990-06-01

    A newly developed biphasic culture system (MB-Check) for recovery of mycobacteria was evaluated. The biphasic system consists of a bottle containing selective modified Middlebrook 7H9 broth and a mounted dip slide with chocolate agar and modified Middlebrook 7H11 agar with and without NAP. The system was compared with culture on two egg-based media, Lowenstein medium and a selective Gottsacker medium, using 995 routine specimens and 90 artificially seeded sputa. Mycobacterium tuberculosis was detected in 17 of the 995 routine specimens by the biphasic system and in 14 specimens by the egg-based media together. In the artificially seeded sputa the biphasic system showed higher sensitivity in detection of both tuberculosis complex and non-tuberculous mycobacteria than the egg-based media. The recovery times of the new system were comparable to those of the two conventional culture methods. PMID:2387296

  17. NF-κB Essential Modulator Deficiency Leading to Disseminated Cutaneous Atypical Mycobacteria

    PubMed Central

    Braue, Jonathan; Murugesan, Vagishwari; Holland, Steven; Patel, Nishit; Naik, Eknath; Leiding, Jennifer; Yacoub, Abraham Tareq; Prieto-Granada, Carlos N; Greene, John Norman

    2015-01-01

    NF-κB essential modulator (NEMO) is a kinase integral to the macrophage TNF-α pathway, which leads to the intracellular destruction of Mycobacteria species. Defects in the NEMO pathway result in spectrum of diseases, including but not limited to ectodermal dysplasia, Mendelian susceptibility to mycobacterial diseases, and incontinentia pigmenti. In addition, paucity of NEMO can lead to the inability to mount a proper immune response against opportunistic pyogenic and mycobacterial infections, leading to dissemination to various organ systems. This manuscript will discuss the numerous clinical manifestations of NEMO deficiency, the differential diagnosis of atypical mycobacterial infections in immunocompetent adults, and feature a case report of rare isolated susceptibility to disseminated atypical mycobacteria due to a mutation in the first exon of the NEMO gene. PMID:25574369

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

    PubMed

    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. PMID:25605389

  19. Characterisation of mycobacteria isolated from slaughter cattle in pastoral regions of Uganda

    PubMed Central

    Oloya, J; Kazwala, R; Lund, A; Opuda-Asibo, J; Demelash, B; Skjerve, E; Johansen, TB; Djønne, B

    2007-01-01

    Background Bovine tuberculosis is a zoonotic problem in pastoral cattle and communities in Uganda. Tuberculin tests in pastoral cattle had shown a high herd but low animal prevalence, with a high proportion of avian reactors. No work had been done to identify the mycobacterial species involved. The objective of the study was to isolate and characterise Mycobacterial species causing tuberculous lesions in slaughtered animals. Lesioned organs compatible with bovine tuberculosis in slaughtered cattle from pastoral areas in Uganda were collected and cultured to isolate mycobacteria. AccuProbe culture identification kits for the Mycobacterium tuberculosis complex, M. avium complex and M. avium were used to identify the isolates. Spoligotyping and Insertion Sequence (IS) 1311 and IS1245 Restriction Fragment Length Polymorphism analysis (RFLP) were used to further characterise the isolates. Results Of the 61 lesioned organs and tissues cultured, 19 isolates were identified as M. bovis, 3 as M. avium subsp.hominissuis, 1 as M. intracellulare, 1 as a mixed culture of M. bovis and M. avium sp. and 1 as M. avium sp. and unidentified mycobacteria. Eleven other mycobacteria outside the tuberculosis and avium complex groups were also isolated. Ten new spoligopatterns grouped into three clusters were identified from M. bovis isolates. Two of the three M. avium subsp.hominissuis isolates showed similar patterns on the IS1311 RFLP but all were different on the IS1245 RFLP. Conclusion The isolation of M. bovis confirms the ongoing infection with spoligotypes unique to Uganda. Isolation of environmental mycobacteria could explain the high avian or non specific tuberculin reactor patterns commonly observed in pastoral cattle and suggests their pathogenic or opportunistic role in the infection of cattle with disseminated bovine tuberculous lesions. PMID:17961243

  20. Heterogeneity among Homologs of Cutinase-Like Protein Cut5 in Mycobacteria

    PubMed Central

    Gambhir, Vandana; Dikshit, Kanak Lata; Varshney, Grish C.

    2015-01-01

    The study of genomic variability within various pathogenic and non-pathogenic strains of mycobacteria provides insight into their evolution and pathogenesis. The mycobacterial genome encodes seven cutinase-like proteins and each one of these exhibit distinct characteristics. We describe the presence of Cut5, a member of the cutinase family, in mycobacteria and the existence of a unique genomic arrangement in the cut5 gene of M. tuberculosis (Mtb) strains. A single nucleotide (T) insertion is observed in the cut5 gene, which is specific for Mtb strains. Using in silico analysis and RT-PCR, we demonstrate the transcription of Rv3724/cut5 as Rv3724a/cut5a and Rv3724b/cut5b in Mtb H37Rv and as full length cut5 in M. bovis. Cut5b protein of Mtb H37Rv (MtbCut5b) was found to be antigenically similar to its homologs in M. bovis and M. smegmatis, without any observed cross-reactivity with other Mtb cutinases. Also, the presence of Cut5b in Mtb and its homologs in M. bovis and M. smegmatis were confirmed by western blotting using antibodies raised against recombinant Cut5b. In Mtb H37Rv, Cut5b was found to be localized in the cell wall, cytosol and membrane fractions. We also report the vast prevalence of Cut5 homologs in pathogenic and non pathogenic species of mycobacteria. In silico analysis revealed that this protein has three possible organizations in mycobacteria. Also, a single nucleotide (T) insertion in Mtb strains and varied genomic arrangements within mycobacterial species make Rv3724/Cut5 a potential candidate that can be exploited as a biomarker in Mtb infection. PMID:26177502

  1. Mycobacteria causing human cervical lymphadenitis in pastoral communities in the Karamoja region of Uganda.

    PubMed

    Oloya, J; Opuda-Asibo, J; Kazwala, R; Demelash, A B; Skjerve, E; Lund, A; Johansen, T B; Djonne, B

    2008-05-01

    Mycobacteria from lymph node biopsies of patients with cervical lymphadenitis reporting for tuberculosis treatment in Matany and Moroto Hospitals in the transhumant areas of Karamoja, Uganda were isolated and characterized. The AccuProbe culture identification kits for Mycobacterium tuberculosis complex (MTC), M. avium complex (MAC) and M. avium were used to identify the isolates. Spoligotyping, IS901 PCR and IS1311 and IS1245 restriction fragment length polymorphism (RFLP) were used to characterize the isolates. Of the 43 biopsies, ten M. avium, seven M. tuberculosis, three M. bovis, and two M. intracellulare were isolated. Two isolates could not be identified with AccuProbe and from 19 samples no mycobacteria could be isolated. Three isolates with the Beijing spoligotype were identified from the seven M. tuberculosis isolates. The spoligopatterns of the M. bovis isolates had previously been detected in cattle in Uganda. Isolation of members of the MAC group reflects the complex interaction between the transhumant communities, water sources and their cattle. None of the M. avium isolates harboured IS901, and all showed several bands on IS1311 and IS1245 RFLP, in accordance with M. avium subsp. hominissuis. Composite dendrograms of IS1311 and IS1245 RFLP showed that the isolates were similar and identical patterns were found. The isolation of M. bovis confirms the human infection with zoonotic mycobacteria in areas where consumption of raw milk and meat is routine. Isolation of environmental mycobacteria also confirms their increasing role in human disease and the occupational risk of infection in the transhumant ecosystem in the absence of safe drinking water and environmental contamination.

  2. Aldehyde-Resistant Mycobacteria Associated with the Use of Endoscope Reprocessing Systems

    PubMed Central

    Fisher, Christopher W.; Fiorello, Anthony; Shaffer, Diana; Jackson, Mary

    2012-01-01

    Bacteria can develop resistance to antibiotics, but less is known about their ability to increase resistance to chemical disinfectants. This study randomly sampled three AERs in the USA using aldehydes for endoscope disinfection. Bacterial contamination was found post-disinfection in all AERs and some mycobacteria isolated demonstrated significant resistance to glutaraldehyde and OPA disinfectants. Bacteria can survive aldehyde-based disinfection and may pose a cross-contamination risk to patients. PMID:22325730

  3. Computational tools to study and understand the intricate biology of mycobacteria.

    PubMed

    Sharma, Deepak; Surolia, Avadhesha

    2011-05-01

    The field of mycobacteriology is currently an area of intense research. To deal with the copious amount of data being generated, numerous web servers and databases have been developed. However, these are available at disparate sites and there exists no single source/platform which provides information about their utility and access. Therefore, a comprehensive compilation of various bioinformatics tools/resources dedicated to mycobacteria is presented in this article. PMID:21398182

  4. Sampling and Decontamination Method for Culture of Nontuberculous Mycobacteria in Respiratory Samples of Cystic Fibrosis Patients

    PubMed Central

    De Geyter, Deborah; De Schutter, Iris; Mouton, Christine; Wellemans, Isabelle; Hanssens, Laurence; Schelstraete, Petra; Malfroot, Anne; Pierard, Denis

    2013-01-01

    We confirmed that chlorhexidine decontamination yielded more nontuberculous mycobacteria than did the N-acetyl-l-cysteine-NaOH-oxalic acid procedure from respiratory samples of cystic fibrosis patients on solid cultures. However, this improved recovery is mostly balanced if the latter is combined with liquid culture. Furthermore, none of the 145 cough swabs, used to sample young children, cultured positive, suggesting that swabs are low-quality samples. PMID:24048532

  5. Evaluation of hemostatic field dressing for bacteria, mycobacteria, or fungus contamination.

    PubMed

    Murray, Clinton K; Brunstetter, Tyson; Beckius, Miriam; Dunne, James R; Mende, Katrin

    2013-03-01

    Infectious complications have a major impact on wounded warriors. Pathogens causing infections include multidrug-resistant bacteria, fungi, and mycobacteria. The potential sources for these pathogens include nosocomial transmission, the environment (e.g., dirt), or the patients (skin flora) themselves. The purpose of this pilot study was to explore the possibility that hemostatic field dressings might act as an inoculation source of pathogens into wounds. To accomplish this, hemostatic field dressings were assessed for the presence of bacterial, fungal, or mycobacterial contamination. We evaluated two samples of QuikClot Combat Gauze and two samples of CELOX Gauze subjected to normal stresses associated with storage after receipt from the manufacturer. We then evaluated 16 samples of QuikClot Combat Gauze that were collected from personnel deployed in Afghanistan and had undergone routine mechanical stress. Samples underwent screening with Trypticase Soy Broth, blood agar plates, MacConkey agar plates, CHROMagar Staphylococcus aureus plates, chocolate agar plates, Potato Flake agar, Lowenstein-Jensen media, and Middlebrook 7H11 media. No bacteria, fungi, or mycobacteria were recovered from the dressings. It does not appear that hemostatic field dressings are contaminated, even after subjected to field conditions. Further research is needed to identify inoculation sources of fungi and mycobacteria, which cause infections.

  6. Evaluation of hemostatic field dressing for bacteria, mycobacteria, or fungus contamination.

    PubMed

    Murray, Clinton K; Brunstetter, Tyson; Beckius, Miriam; Dunne, James R; Mende, Katrin

    2013-03-01

    Infectious complications have a major impact on wounded warriors. Pathogens causing infections include multidrug-resistant bacteria, fungi, and mycobacteria. The potential sources for these pathogens include nosocomial transmission, the environment (e.g., dirt), or the patients (skin flora) themselves. The purpose of this pilot study was to explore the possibility that hemostatic field dressings might act as an inoculation source of pathogens into wounds. To accomplish this, hemostatic field dressings were assessed for the presence of bacterial, fungal, or mycobacterial contamination. We evaluated two samples of QuikClot Combat Gauze and two samples of CELOX Gauze subjected to normal stresses associated with storage after receipt from the manufacturer. We then evaluated 16 samples of QuikClot Combat Gauze that were collected from personnel deployed in Afghanistan and had undergone routine mechanical stress. Samples underwent screening with Trypticase Soy Broth, blood agar plates, MacConkey agar plates, CHROMagar Staphylococcus aureus plates, chocolate agar plates, Potato Flake agar, Lowenstein-Jensen media, and Middlebrook 7H11 media. No bacteria, fungi, or mycobacteria were recovered from the dressings. It does not appear that hemostatic field dressings are contaminated, even after subjected to field conditions. Further research is needed to identify inoculation sources of fungi and mycobacteria, which cause infections. PMID:23707133

  7. Distribution and Respiratory Activity of Mycobacteria in Household Water System of Healthy Volunteers in Japan

    PubMed Central

    Ichijo, Tomoaki; Izumi, Yoko; Nakamoto, Sayuri; Yamaguchi, Nobuyasu; Nasu, Masao

    2014-01-01

    The primary infectious source of nontuberculous mycobacteria (NTM), which are known as opportunistic pathogens, appears to be environmental exposure, and it is important to reduce the frequency of exposure from environmental sources for preventing NTM infections. In order to achieve this, the distribution and respiratory activity of NTM in the environments must be clarified. In this study, we determined the abundance of mycobacteria and respiratory active mycobacteria in the household water system of healthy volunteers using quantitative PCR and a fluorescent staining method, because household water has been considered as one of the possible infectious sources. We chose healthy volunteer households in order to lessen the effect of possible residential contamination from an infected patient. We evaluated whether each sampling site (bathroom drain, kitchen drain, bath heater pipe and showerhead) have the potential to be the sources of NTM infections. Our results indicated that drains in the bathroom and kitchen sink are the niche for Mycobacterium spp. and M. avium cells were only detected in the bathtub inlet. Both physicochemical and biologic selective pressures may affect the preferred habitat of Mycobacterium spp. Regional differences also appear to exist as demonstrated by the presence (US) or absence (Japan) of Mycobacterium spp. on showerheads. Understanding of the country specific human activities and water usage will help to elucidate the infectious source and route of nontuberculous mycobacterial disease. PMID:25350137

  8. Comparison of the activities of the lantibiotics nisin and lacticin 3147 against clinically significant mycobacteria.

    PubMed

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

    2010-08-01

    The aim of this study was to use the microtitre alamarBlue assay to investigate and compare the antimycobacterial potential of the lantibiotics nisin and lacticin 3147 against a representative cohort of clinically significant mycobacteria, i.e. Mycobacterium tuberculosis H37Ra, Mycobacterium avium subsp. paratuberculosis (MAP) ATCC 19698 and Mycobacterium kansasii CIT11/06. Lacticin 3147 displayed potent activity against all strains of mycobacteria, with MIC(90) values (lowest concentration of lantibiotic that prevented growth of >90% of the bacterial population) of 60 mg/L and 15 mg/L for M. kansasii and MAP, respectively. Lacticin 3147 was particularly effective against M. tuberculosis H37Ra, with a MIC(90) value of 7.5mg/L. Nisin, although inhibitory, was generally less potent against all strains of mycobacteria, with MIC(90) values of 60 mg/L for M. kansasii and >60 mg/L for MAP and M. tuberculosis H37Ra. Thus, lacticin 3147 is a potent antimycobacterial peptide that shows superior activity compared with nisin at physiological pH. PMID:20547041

  9. Detection of mycobacteria in aquarium fish in Slovenia by culture and molecular methods.

    PubMed

    Pate, M; Jencic, V; Zolnir-Dovc, M; Ocepek, M

    2005-04-01

    Thirty-five aquarium fish were investigated for the presence of mycobacteria by culture and molecular methods. The following species were examined: goldfish Carassius auratus auratus, guppy Poecilia reticulata, 4 three-spot gourami Trichogaster trichopterus, dwarf gourami Colisa lalia, Siamese fighting fish Betta splendens, freshwater angelfish Pterophyllum scalare, African cichlid fish Cichlidae spp., cichlid fish Microgeophagus altispinosus, cichlid fish Pseudotropheus lombardoi, blue streak hap Labidochromis caeruleus, sterlet Acipenser ruthenus, southern platyfish Xiphophorus maculatus, and catfish Corydoras spp. Isolates of mycobacteria were obtained in 29 cases (82.9%). Two specimens were positive using Ziehl-Neelsen (ZN) staining, but the cultivation failed. Four specimens were both ZN- and culture-negative. On the basis of GenoType Mycobacterium assay (Hain Life-science) and restriction enzyme analysis of the amplified products (PCR-RFLP), 23 isolates (79.3%) were identified: 7 as Mycobacterium fortuitum, 6 as M. gordonae, 6 as M. marinum, 3 as M. chelonae, and 1 as M. peregrinum. Five isolates remained unidentified (Mycobacterium spp.). One case probably represented a mixed infection (M. marinum/M. fortuitum). Since M. marinum infections are also detected in humans, the significance of mycobacteria in aquarium fish should not be overlooked. PMID:15900685

  10. Identification of Nontuberculous Mycobacteria Species Isolated from Water Samples Using Phenotypic and Molecular Methods and Determination of their Antibiotic Resistance Patterns by E- Test Method, in Isfahan, Iran

    PubMed Central

    Moghim, Sharareh; Sarikhani, Ensieh; Nasr Esfahani, Bahram; Faghri, Jamshid

    2012-01-01

    Introduction Many studies have shown epidemiological links between strains isolated in tap water, and those isolated from patients. Molecular methods linked to PCR are more reliable and faster for identification of non- tuberculous mycobacteria (NTM). In this study molecular methods were used for identification and typing of NTM. Materials and Methods Five hundred ml of 85 water samples was passed through 0.45 μm filters. The filters were transferred directly onto 7H10 Middle Brook solid media, containing 15% OADC. PCR for 16S rRNA was done and the PCR product (1500 bp) was sequenced. PRA of the hsp65 gene was investigated to identify the species of isolates. For evaluation of susceptibility of NTM to antimycobacterial agents, E-test method was used. Result The genus of 26 isolated NTM was confirmed by 16s rRNA sequence based method. Nineteen isolates of Mycobacteria were differentiated using hsp65 genes PRA. The dominant isolates were M. fortuitum (26.7%), M. chelonae like organism (13.3%) and M. mucogenicum (13.3%). Seventy one percent of NTM species were resistant to isoniazid, 64% to rifampin, 57% to ethambutol, 35% to tetracycline, 14 % to azithromycin and 7.1 % to amikacin. Conclusion The results showed that E-test method is not a proper technique for antimycobacterial assay because some NTM species are slow in growing and have no growth on Muller Hinton agar. Regarding the 16S rRNA sequence analysis, the identification of isolates was restricted to the genus level, because 99% similarity within 16S rRNA of two isolates may or may not determine the same species. PMID:23493797

  11. Rapid Reagentless Detection of M. tuberculosis H37Ra in Respiratory Effluents

    SciTech Connect

    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.

  12. Interdigitated array microelectrode capacitive sensor for detection of paraffinophilic mycobacteria

    NASA Astrophysics Data System (ADS)

    Sampson, Andrew M.; Peterson, Erik T. K.; Papautsky, Ian

    2008-02-01

    Mycobacterium Avium Complex (MAC) is an opportunistic pathogen that threatens public health and has high clinical relevance. While culture-based and molecular biology techniques for identification are available, these methods are prone to error and require weeks to perform. There is a critical need for improved portable lab-on-a-chip sensor technology which will enable accurate and rapid point-of-care detection of these microorganisms. In this work, a new capacitive sensing strategy is explored utilizing interdigitated array (IDA) microelectrodes and exploiting the paraffinophilic nature of MAC. In this approach, paraffin wax is deposited over IDA microelectrodes to selectively extract these microorganisms from samples. As bacteria consume the dielectric paraffin layer, the charging current of the IDA capacitor changes to facilitate detection. Several IDA geometries were designed and simulated using CFD-ACE+ modeling software and compared with mathematical models. Capacitance of fabricated devices was determined using a charge-based capacitance measurement (CBCM) technique. Modeling and experimental results were in good agreement. Detection of femto-Farad changes in capacitance is possible, making this a feasible technique for sensing small changes in the paraffin for detection of paraffinophilic MAC.

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

    PubMed

    Klanicova, Barbora; Seda, Jaromir; Slana, Iva; Slany, Michal; Pavlik, Ivo

    2013-12-01

    Mycobacteria are widely present in diverse aquatic habitats, where they can survive for months or years while some species can even proliferate. The resistance of different mycobacterial species to disinfection methods like chlorination or ozonation could result in their presence in the final tap water of consumers. In this study, the culture method, Mycobacterium tuberculosis complex conventional duplex PCR for detection of non-tuberculous mycobacteria (NTM) and quantitative real-time PCR (qPCR) to detect three subspecies of M. avium species (M. a. avium, M. a. hominissuis, and M. a. paratuberculosis) were used to trace their possible path of transmission from the watershed through the reservoir and drinking water plant to raw drinking water and finally to households. A total of 124 samples from four drinking water supply systems in the Czech Republic, 52 dam sediments, 34 water treatment plant sludge samples, and 38 tap water household sediments, were analyzed. NTM of 11 different species were isolated by culture from 42 (33.9 %) samples; the most prevalent were M. gordonae (16.7 %), M. triplex (14.3 %), M. lentiflavum (9.5 %), M. a. avium (7.1 %), M. montefiorenase (7.1 %), and M. nonchromogenicum (7.1 %). NTM DNA was detected in 92 (76.7 %) samples. By qPCR analysis a statistically significant decrease (P < 0.01) was observed along the route from the reservoir (dam sediments), through water treatment sludge and finally to household sediments. The concentrations ranged from 10(0) to 10(4) DNA cells/g. It was confirmed that drinking water supply systems (watershed-reservoir-drinking water treatment plant-household) might be a potential transmission route for mycobacteria.

  14. Potential cross-reactivity of monoclonal antibodies against clinically relevant mycobacteria.

    PubMed

    Flores-Moreno, K; Celis-Meneses, J S; Meneses-Ruiz, D M; Castillo-Rodal, A I; Orduña, P; Montiel, B A; López-Vidal, Y

    2014-08-01

    Tuberculosis is a disease caused by the Mycobacterium tuberculosis complex (MTb). In 2011, global mortality due to tuberculosis was 1·4 million individuals. The only available vaccine is the attenuated M. bovis [bacillus Calmette-Guérin (BCG)] strain, which confers variable protection against pulmonary tuberculosis. Some widely distributed non-tuberculous mycobacteria (NTM), such as M. avium and M. arupense, are also potential pathogens for humans. This work aimed to produce and characterize monoclonal antibodies against the M. bovis BCG Mexico strain of the MTb, M. avium subs. hominissuis and the M. arupense strain from NTM. Hybridomas were produced from splenocytes of BALB/c female mice immunized with radiation-inactivated mycobacteria, and the immunoglobulin (Ig)G2a antibody-producing clones with the highest antigenic recognition were selected. The selected clones, Mbv 2A10 for M. bovis BCG Mexico, Mav 3H1 for M. avium and Mar 2D10 for M. arupense, were used in further studies. Enzyme-linked immunosorbent assay (ELISA) and immune proteomics analyses characterized the clones as having the highest cross-reactivity with mycobacteria. Using mass spectrometry, a number of proteins recognized by the monoclonal antibody (mAb) clones were identified. These proteins had roles in metabolic processes, hypoxia, cell cycle and dormancy. In addition, a Clustal W and Immune Epitope Database (IEDB) in-silico analysis was performed in protein sequences that result in the conserved regions within probability epitopes that could be recognized for Mbv2A10 and Mav3H1 clones.

  15. Potential cross-reactivity of monoclonal antibodies against clinically relevant mycobacteria

    PubMed Central

    Flores-Moreno, K; Celis-Meneses, J S; Meneses-Ruiz, D M; Castillo-Rodal, A I; Orduña, P; Montiel, B A; López-Vidal, Y

    2014-01-01

    Tuberculosis is a disease caused by the Mycobacterium tuberculosis complex (MTb). In 2011, global mortality due to tuberculosis was 1·4 million individuals. The only available vaccine is the attenuated M. bovis [bacillus Calmette–Guérin (BCG)] strain, which confers variable protection against pulmonary tuberculosis. Some widely distributed non-tuberculous mycobacteria (NTM), such as M. avium and M. arupense, are also potential pathogens for humans. This work aimed to produce and characterize monoclonal antibodies against the M. bovis BCG Mexico strain of the MTb, M. avium subs. hominissuis and the M. arupense strain from NTM. Hybridomas were produced from splenocytes of BALB/c female mice immunized with radiation-inactivated mycobacteria, and the immunoglobulin (Ig)G2a antibody-producing clones with the highest antigenic recognition were selected. The selected clones, Mbv 2A10 for M. bovis BCG Mexico, Mav 3H1 for M. avium and Mar 2D10 for M. arupense, were used in further studies. Enzyme-linked immunosorbent assay (ELISA) and immune proteomics analyses characterized the clones as having the highest cross-reactivity with mycobacteria. Using mass spectrometry, a number of proteins recognized by the monoclonal antibody (mAb) clones were identified. These proteins had roles in metabolic processes, hypoxia, cell cycle and dormancy. In addition, a Clustal W and Immune Epitope Database (IEDB) in-silico analysis was performed in protein sequences that result in the conserved regions within probability epitopes that could be recognized for Mbv2A10 and Mav3H1 clones. PMID:24580144

  16. Distribution of mycobacteria in clinically healthy ornamental fish and their aquarium environment.

    PubMed

    Beran, V; Matlova, L; Dvorska, L; Svastova, P; Pavlik, I

    2006-07-01

    Some mycobacterial species (particularly Mycobacterium marinum) found in aquarium environments may cause chronic diseases in fish and cutaneous infections in humans, the so-called 'fish tank granuloma'. The presence and distribution of mycobacterial species in clinically healthy aquarium fish and their environment has not been adequately explored. The present study analysed the occurrence of mycobacteria in a decorative aquarium (Brno, South Moravia) and in five aquaria of a professional fish breeder (Bohumin, North Moravia). After Ziehl-Neelsen staining, acid-fast rods (AFR) were observed in six (14.3%) and mycobacteria were detected by culture in 18 (42.9%) of 42 tissue samples from 19 fish. Sixty-five samples of the aqueous environment from all six aquaria were examined; AFR were found in 16 (24.6%) and mycobacteria were detected by culture in 49 (75.4%) samples. Forty-one (70.7%) of 58 selected mycobacterial isolates were identified biochemically as follows: M. fortuitum, M. flavescens, M. chelonae, M. gordonae, M. terrae, M. triviale, M. diernhoferi, M. celatum, M. kansasii and M. intracellulare. The clinically important species for humans and fish, M. marinum, was not detected. Mycobacterium kansasii was isolated from one sample of the aquarium environment from North Moravia, which is a region of the Czech Republic with endemic incidence of M. kansasii in water. The incidence of other conditionally pathogenic mycobacterial species in healthy fish and in all investigated constituents of the aquarium environment including snails and crustaceans used for fish feeding, was quite high. Accordingly, mycobacterial species from aquarium environments may serve as a possible source of infection for both aquarium fish and immunodeficient fish handlers.

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

    SciTech Connect

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

    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.

  18. Application of a quantitative carrier test to evaluate microbicides against mycobacteria.

    PubMed

    Springthorpe, V Susan; Sattar, Syed A

    2007-01-01

    Microbicides for reprocessing heat-sensitive medical devices, such as flexible endoscopes, must be mycobactericidal to reduce the risk of nosocomial infections. Suspension test methods currently used for efficacy evaluation lack the stringency required for assessing inactivation of mycobacteria on surfaces. The quantitative carrier test method reported here is based on mycobacteria-contaminated reference carrier disks of brushed stainless steel. Each disk was contaminated with 10 microL of a suspension of Mycobacterium terrae containing a soil load. Each disk with a dried inoculum was placed in a glass or Teflon vial, and then overlaid with 50 microL of the test formulation or 50 microL saline for the control carriers. Five test and 3 control disks were used in each run. At the end of the contact time, each vial received 9.95 mL neutralizer solution with 0.1% Tween-80 to stop the reaction and perform the initial microbicide dilution. The inoculum was eluted by mixing on a Vortex mixer for 60 s, and the eluates and saline used to subsequently wash the vials and the funnels were membrane-filtered. Filters were placed on plates of Middlebrook 7H11 agar and incubated at 37 degrees C for at least 30 days before colonies were counted and log10 reductions were calculated in colony-forming units. Tests with a range of commercially available products, having claims against mycobacteria, or believed to be broad-spectrum microbicides, showed that the method gave reproducible results. Products used included oxidizing agents (sodium hypochlorite and an iodophore), a phenolic, a quaternary ammonium compound, and ortho-phthalaldehyde. This method represents a much more realistic evaluation than the currently used quantitative suspension test method for the evaluation of mycobactericidal formulations for registration and, when performed at different product concentrations, allows an assessment of any safety margin or risks in using the test formulation in the field.

  19. Two liquid medium systems, mycobacteria growth indicator tube and MB redox tube, for Mycobacterium tuberculosis isolation from sputum specimens.

    PubMed

    Heifets, L; Linder, T; Sanchez, T; Spencer, D; Brennan, J

    2000-03-01

    Two manual liquid medium systems, the Mycobacteria Growth Indicator Tube (MGIT) and MB Redox tube systems, were evaluated in comparison to the radiometric BACTEC-460 semiautomated system for recovery of Mycobacterium tuberculosis from sputum specimens. The highest level of recovery, from a total of 77 culture-positive specimens, occurred with the BACTEC-460 system (92.2%), followed by the MB Redox tube (80.5%) and the MGIT (63.6%) systems. The shortest time to detection was observed also among the cultures in BACTEC-460: a mean of 12 days to a growth index (GI) of 10 and 15 days to a GI of 500. The mean times for the other systems were 16 days for the MB Redox tube system and 17.4 days for the MGIT system. The proportion of cultures grown after more than 3 weeks of incubation was only 2.8 or 8.4% in BACTEC-460 (for a GI of 10 or 500) but 17.7% in MB Redox and 22.5% in MGIT. Despite these differences in comparison to the BACTEC-460 system and some differences between the MGIT and MB Redox tube systems, either of the two manual liquid medium systems presents a reasonable alternative to the BACTEC-460 system, especially for laboratories with a limited workload, and a valuable element in the laboratory protocol, in conjunction with solid media, for obtaining rapid detection of growth from about 80% of culture-positive specimens and for better overall recovery of M. tuberculosis. PMID:10699027

  20. Multicenter evaluation of fully automated BACTEC Mycobacteria Growth Indicator Tube 960 system for susceptibility testing of Mycobacterium tuberculosis.

    PubMed

    Bemer, Pascale; Palicova, Frantiska; Rüsch-Gerdes, Sabine; Drugeon, Henri B; Pfyffer, Gaby E

    2002-01-01

    The reliability of the BACTEC Mycobacteria Growth Indicator Tube (MGIT) 960 system for testing of Mycobacterium tuberculosis susceptibility to the three front-line drugs (isoniazid [INH], rifampin [RIF], and ethambutol [EMB]) plus streptomycin (STR) was compared to that of the BACTEC 460 TB system. The proportion method was used to resolve discrepant results by an independent arbiter. One hundred and ten strains were tested with an overall agreement of 93.5%. Discrepant results were obtained for seven strains (6.4%) with INH (resistant by BACTEC MGIT 960; susceptible by BACTEC 460 TB), for one strain (0.9%) with RIF (resistant by BACTEC MGIT 960; susceptible by BACTEC 460 TB), for seven strains (6.4%) with EMB (six resistant by BACTEC MGIT 960 and susceptible by BACTEC 460 TB; one susceptible by BACTEC MGIT 960 and resistant by BACTEC 460 TB), and for 19 strains (17.3%) with STR (resistant by BACTEC MGIT 960 and susceptible by BACTEC 460 TB). After resolution of discrepant results, the sensitivity of the BACTEC MGIT 960 system was 100% for all four drugs and specificity ranged from 89.8% for STR to 100% for RIF. Turnaround times were 4.6 to 11.7 days (median, 6.5 days) for BACTEC MGIT 960 and 4.0 to 10.0 days (median, 7.0 days) for BACTEC 460 TB. These data demonstrate that the fully automated and nonradiometric BACTEC MGIT 960 system is an accurate method for rapid susceptibility testing of M. tuberculosis.

  1. Multicenter Evaluation of Fully Automated BACTEC Mycobacteria Growth Indicator Tube 960 System for Susceptibility Testing of Mycobacterium tuberculosis

    PubMed Central

    Bemer, Pascale; Palicova, Frantiska; Rüsch-Gerdes, Sabine; Drugeon, Henri B.; Pfyffer, Gaby E.

    2002-01-01

    The reliability of the BACTEC Mycobacteria Growth Indicator Tube (MGIT) 960 system for testing of Mycobacterium tuberculosis susceptibility to the three front-line drugs (isoniazid [INH], rifampin [RIF], and ethambutol [EMB]) plus streptomycin (STR) was compared to that of the BACTEC 460 TB system. The proportion method was used to resolve discrepant results by an independent arbiter. One hundred and ten strains were tested with an overall agreement of 93.5%. Discrepant results were obtained for seven strains (6.4%) with INH (resistant by BACTEC MGIT 960; susceptible by BACTEC 460 TB), for one strain (0.9%) with RIF (resistant by BACTEC MGIT 960; susceptible by BACTEC 460 TB), for seven strains (6.4%) with EMB (six resistant by BACTEC MGIT 960 and susceptible by BACTEC 460 TB; one susceptible by BACTEC MGIT 960 and resistant by BACTEC 460 TB), and for 19 strains (17.3%) with STR (resistant by BACTEC MGIT 960 and susceptible by BACTEC 460 TB). After resolution of discrepant results, the sensitivity of the BACTEC MGIT 960 system was 100% for all four drugs and specificity ranged from 89.8% for STR to 100% for RIF. Turnaround times were 4.6 to 11.7 days (median, 6.5 days) for BACTEC MGIT 960 and 4.0 to 10.0 days (median, 7.0 days) for BACTEC 460 TB. These data demonstrate that the fully automated and nonradiometric BACTEC MGIT 960 system is an accurate method for rapid susceptibility testing of M. tuberculosis. PMID:11773109

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

    PubMed

    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. PMID:26810616

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

    PubMed

    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.

  4. Immunological Evidence for the Role of Mycobacteria in Sarcoidosis: A Meta-Analysis

    PubMed Central

    Fang, Chuling; Huang, Hui; Xu, Zuojun

    2016-01-01

    Background Sarcoidosis is a granulomatous disease, the etiology of which is currently unknown. The role of mycobacteria in the etiology of sarcoidosis has been extensively investigated. In this meta-analysis, we assessed the immunological evidence of the possible role of mycobacteria in the pathogenesis and development of sarcoidosis. Methods We performed a systematic search of relevant articles from PubMed, Embase and Cochrane Library databases published between January 1990 and October 2015. Data extracted from the articles were analyzed with Review Manager 5.3 (Cochrane Collaboration, Oxford, UK). Results In this meta-analysis, 13 case-control studies (733 participants) were considered eligible according to our criteria. Methodological quality was assessed using the Newcastle-Ottawa Scale (NOS). The positivity incidence of the immune response (either the cell-mediated response or humoral response) in sarcoidosis patients was significantly higher than that in controls, as determined using fixed-effects model. The odds ratio (OR) of the positivity incidence of T-cell response in the patients with sarcoidosis versus the controls with PPD- or unknown PPD status was 5.54 (95% CI 3.56–8.61); the ORs were 16.70 (95% CI 8.19–34.08) and 1.48 (95% CI 0.74–2.96) for the two subgroups with PPD- controls and unknown PPD status respectively. However, the OR of the positivity incidence in patients with sarcoidosis versus PPD+ controls (latent tuberculosis infection; LTBI) was 0.26 (95% 0.10–0.66). Regarding the humoral response, pooled analysis of the positivity incidence revealed an OR (95%CI) of 20.43 (5.53–75.53) for the patients with sarcoidosis versus controls; the ORs were 11.93 (95% CI 2.15–66.27) and 41.97 (95% CI 5.24–336.15) in two subgroups of controls with PPD- and unknown PPD statuses respectively. Data on heterogeneity and evidence of publication bias were examined. Conclusions This meta-analysis confirmed the existence of an association between

  5. Environmental Risks for Nontuberculous Mycobacteria. Individual Exposures and Climatic Factors in the Cystic Fibrosis Population

    PubMed Central

    Adjemian, Jennifer; Fernandez, Aisling G.; Knowles, Michael R.; Olivier, Kenneth N.

    2014-01-01

    Rationale: Persons with cystic fibrosis are at high risk of pulmonary nontuberculous mycobacterial infection, with a national prevalence estimated at 13%. The risk of nontuberculous mycobacteria associated with specific environmental exposures, and the correlation with climatic conditions in this population has not been described. Objectives: To describe the association of pulmonary nontuberculous mycobacteria with individual exposures to water and soil aerosols, and the population associations of these infections with climatic factors. Methods: We conducted a nested case–control study within a cohort study of pulmonary nontuberculous mycobacteria prevalence at 21 geographically diverse national cystic fibrosis centers. Incident nontuberculous mycobacterial infection cases (at least one prior negative culture followed by one positive culture) were age- and sex-matched to culture-negative controls. Exposures to water and soil were assessed by administering a standardized questionnaire. Cohort prevalence at each of the 21 centers was correlated with climatic conditions in the same area through linear regression modeling. Measurements and Main Results: Overall, 48 cases and 85 control subjects were enrolled. Indoor swimming was associated with incident infection (adjusted odds ratio, 5.9, 95% confidence interval, 1.3–26.1), although only nine cases (19%) and five control subjects (6%) reported indoor swimming in the 4 months prior to infection. Exposure to showering and municipal water supply was common among both cases and control subjects: 77% of cases and 76% of control subjects reported showering at least daily. In linear regression, average annual atmospheric water vapor content was significantly predictive of center prevalence (P = 0.0019), with R2 = 0.40. Conclusions: Atmospheric conditions explain more of the variation in disease prevalence than individual behaviors. The risk of specific exposures may vary by geographic region due to differences in

  6. Evaluation of an immunochromatographic assay for rapid identification of Mycobacterium tuberculosis complex in clinical isolates.

    PubMed

    Marzouk, Manel; Kahla, Imen Ben; Hannachi, Naila; Ferjeni, Asma; Salma, Walid Ben; Ghezal, Samira; Boukadida, Jalel

    2011-04-01

    Identification of Mycobacterium tuberculosis complex (MTC) remains slow. Over the years, several new technologies have been proposed to accelerate and simplify the detection of MTC. In this context, we evaluated an immunochromatographic assay (ICA) (BIO-LINE SD Ag MPT64 TB) for rapid identification of MTC, based on detection of a specific MPT64 antigen of MTC. We have tested it on i) mycobacterial cultures: 210 MTC strains and 28 nontuberculous mycobacteria; ii) M. bovis bacille Calmette-Guérin strain SSI (Statens Serum Institut, Denmark); and iii) 22 microorganisms other than mycobacteria, isolated from cultures. We concluded that this kit has an excellent specificity (100%) and sensitivity (99%) from isolated cultures. The ICA (BIO-LINE SD Ag MPT64 TB) allows excellent MTC identification from clinical isolates. It is a rapid, simple, and inexpensive test, and has a definite contribution in the rapid laboratory diagnosis of tuberculosis. PMID:21396535

  7. Carbonaceous Matter in Growing Nanoparticles

    NASA Astrophysics Data System (ADS)

    Johnston, M. V.; Stangl, C. M.; Horan, A. J.

    2015-12-01

    Atmospheric nanoparticles constitute the greatest portion of ambient aerosol loading by number. A major source of atmospheric nanoparticles is new particle formation (NPF), a gas to particle conversion process whereby clusters nucleate from gas phase precursors to form clusters on the order of one or a few nanometers and then grow rapidly to climatically relevant sizes. A substantial fraction of cloud condensation nuclei (CCN) are thought to arise from NPF. In order to better predict the frequency, growth rates, and climatic impacts of NPF, knowledge of the chemical mechanisms by which nucleated nanoparticles grow is needed. The two main contributors to particle growth are (neutralized) sulfate and carbonaceous matter. Particle growth by sulfuric acid condensation is generally well understood, though uncertainty remains about the extent of base neutralization and the relative roles of ammonia and amines. Much less is known about carbonaceous matter, and field measurements suggest that nitrogen-containing species are important. In this presentation, recent work by our group will be described that uses a combination of ambient measurements, laboratory experiments and computational work to study carbonaceous matter in growing nanoparticles. These studies span a range of particle sizes from the initial adsorption of molecules onto a nanometer-size ammonium bisulfate seed cluster to reactions in particles that are large enough to support condensed-phase chemistry.

  8. Apparatus for growing crystals

    NASA Technical Reports Server (NTRS)

    Jasinski, Thomas J. (Inventor); Witt, August F. (Inventor)

    1986-01-01

    An improved apparatus and method for growing crystals from a melt employing a heat pipe, consisting of one or more sections, each section serving to control temperature and thermal gradients in the crystal as it forms inside the pipe.

  9. How Your Baby Grows

    MedlinePlus

    ... brain, the heart and lungs, are forming. The placenta grows in your uterus and supplies the baby ... like alcohol, cigarette smoke and drugs through the placenta, too. So don’t drink alcohol , smoke , use ...

  10. Hypersensitivity Pneumonitis-like Granulomatous Lung Disease with Nontuberculous Mycobacteria from Exposure to Hot Water Aerosols

    PubMed Central

    Sood, Akshay; Sreedhar, Rajgopal; Kulkarni, Pradeep; Nawoor, Abdur Ray

    2007-01-01

    Objective Human activities associated with aerosol-generating hot water sources are increasingly popular. Recently, a hypersensitivity pneumonitis (HP)-like granulomatous lung disease, with non-tuberculous mycobacteria from exposure to hot water aerosols from hot tubs/spas, showers, and indoor swimming pools, has been described in immunocompetent individuals (also called “hot tub lung”). Our objective in this study was to examine four additional cases of hot tub lung and compare these cases with others reported in the English print literature on this disease. Data sources and extraction We retrospectively reviewed all cases (n = 4) of presumptively diagnosed hot tub lung in immunocompetent individuals at the various physician practices in Springfield, Illinois, during 2001–2005. In addition, we searched MEDLINE for cases of hot tub lung described in the literature. Data synthesis We summarized the clinical presentation and investigations of four presumptive cases and reviewed previously reported cases of hot tub lung. Conclusions There is a debate in the literature whether hot tub lung is an HP or a direct infection of the lung by nontuberculous mycobacteria. Primary prevention of this disease relies on ventilation and good use practices. Secondary prevention of this disease requires education of both the general public and clinicians to allow for the early diagnosis of this disease. PMID:17384775

  11. Methodological and Clinical Aspects of the Molecular Epidemiology of Mycobacterium tuberculosis and Other Mycobacteria.

    PubMed

    Jagielski, Tomasz; Minias, Alina; van Ingen, Jakko; Rastogi, Nalin; Brzostek, Anna; Żaczek, Anna; Dziadek, Jarosław

    2016-04-01

    Molecular typing has revolutionized epidemiological studies of infectious diseases, including those of a mycobacterial etiology. With the advent of fingerprinting techniques, many traditional concepts regarding transmission, infectivity, or pathogenicity of mycobacterial bacilli have been revisited, and their conventional interpretations have been challenged. Since the mid-1990s, when the first typing methods were introduced, a plethora of other modalities have been proposed. So-called molecular epidemiology has become an essential subdiscipline of modern mycobacteriology. It serves as a resource for understanding the key issues in the epidemiology of tuberculosis and other mycobacterial diseases. Among these issues are disclosing sources of infection, quantifying recent transmission, identifying transmission links, discerning reinfection from relapse, tracking the geographic distribution and clonal expansion of specific strains, and exploring the genetic mechanisms underlying specific phenotypic traits, including virulence, organ tropism, transmissibility, or drug resistance. Since genotyping continues to unravel the biology of mycobacteria, it offers enormous promise in the fight against and prevention of the diseases caused by these pathogens. In this review, molecular typing methods for Mycobacterium tuberculosis and nontuberculous mycobacteria elaborated over the last 2 decades are summarized. The relevance of these methods to the epidemiological investigation, diagnosis, evolution, and control of mycobacterial diseases is discussed.

  12. Proteomic Analysis of Drug-Resistant Mycobacteria: Co-Evolution of Copper and INH Resistance.

    PubMed

    Chen, Yuling; Yang, Fan; Sun, Zhongyuan; Wang, Qingtao; Mi, Kaixia; Deng, Haiteng

    2015-01-01

    Tuberculosis, caused by the pathogen Mycobacterium tuberculosis, is a worldwide public health threat. Mycobacterium tuberculosis is capable of resisting various stresses in host cells, including high levels of ROS and copper ions. To better understand the resistance mechanisms of mycobacteria to copper, we generated a copper-resistant strain of Mycobacterium smegmatis, mc2155-Cu from the selection of copper sulfate treated-bacteria. The mc2155-Cu strain has a 5-fold higher resistance to copper sulfate and a 2-fold higher resistance to isoniazid (INH) than its parental strain mc2155, respectively. Quantitative proteomics was carried out to find differentially expressed proteins between mc2155 and mc2155-Cu. Among 345 differentially expressed proteins, copper-translocating P-type ATPase was up-regulated, while all other ABC transporters were down-regulated in mc2155-Cu, suggesting copper-translocating P-type ATPase plays a crucial role in copper resistance. Results also indicated that the down-regulation of metabolic enzymes and decreases in cellular NAD, FAD, mycothiol, and glutamine levels in mc2155-Cu were responsible for its slowing growth rate as compared to mc2155. Down-regulation of KatG2 expression in both protein and mRNA levels indicates the co-evolution of copper and INH resistance in copper resistance bacteria, and provides new evidence to understanding of the molecular mechanisms of survival of mycobacteria under stress conditions.

  13. Dynamic exometabolome analysis reveals active metabolic pathways in non-replicating mycobacteria.

    PubMed

    Zimmermann, Michael; Kuehne, Andreas; Boshoff, Helena I; Barry, Clifton E; Zamboni, Nicola; Sauer, Uwe

    2015-11-01

    An organism's metabolic activity leaves an extracellular footprint and dynamic changes in this exometabolome inform about nutrient uptake, waste disposal and signalling activities. Using non-targeted mass spectrometry, we report exometabolome dynamics of hypoxia-induced, non-replicating mycobacteria that are thought to play a role in latent tuberculosis. Despite evidence of active metabolism, little is known about the mechanisms enabling obligate aerobic mycobacteria to cope with hypoxia, resulting in long-term survival and increased chemotherapeutic tolerance. The dynamics of 379 extracellular compounds of Mycobacterium smegmatis were deconvoluted with a genome-scale metabolic reaction-pair network to generate hypotheses about intracellular pathway usage. Time-resolved (13) C-tracing and mutant experiments then demonstrated a crucial, energy-generating role of asparagine utilization and non-generic usage of the glyoxylate shunt for hypoxic fitness. Experiments with M. bovis and M. tuberculosis revealed the general relevance of asparagine fermentation and a variable contribution of the glyoxylate shunt to non-replicative, hypoxic survival between the three species.

  14. Extraordinary solute-stress tolerance contributes to the environmental tenacity of mycobacteria.

    PubMed

    Santos, Ricardo; de Carvalho, Carla C C R; Stevenson, Andrew; Grant, Irene R; Hallsworth, John E

    2015-10-01

    Mycobacteria are associated with a number of well-characterized diseases, yet we know little about their stress biology in natural ecosystems. This study focuses on the isolation and characterization of strains from Yellowstone National Park (YNP) and Glacier National Park (GNP; USA), the majority of those identified were Mycobacterium parascrofulaceum, Mycobacterium avium (YNP) or Mycobacterium gordonae (GNP). Generally, their windows for growth spanned a temperature range of > 60 °C; selected isolates grew at super-saturated concentrations of hydrophobic stressors and at levels of osmotic stress and chaotropic activity (up to 13.4 kJ kg(-1) ) similar to, or exceeding, those for the xerophilic fungus Aspergillus wentii and solvent-tolerant bacterium Pseudomonas putida. For example, mycobacteria grew down to 0.800 water activity indicating that they are, with the sole exception of halophiles, more xerotolerant than other bacteria (or any Archaea). Furthermore, the fatty-acid composition of Mycobacterium cells grown over a range of salt concentrations changed less than that of other bacteria, indicating a high level of resilience, regardless of the stress load. Cells of M. parascrofulaceum, M. smegmatis and M. avium resisted the acute, potentially lethal challenges from extremes of pH (< 1; > 13), and saturated MgCl2 solutions (5 M; 212 kJ kg(-1) chaotropicity). Collectively, these findings challenge the paradigm that bacteria have solute tolerances inferior to those of eukaryotes.

  15. Improved recovery of mycobacteria from respiratory secretions of patients with cystic fibrosis.

    PubMed

    Whittier, S; Hopfer, R L; Knowles, M R; Gilligan, P H

    1993-04-01

    Pulmonary colonization and infection of patients with cystic fibrosis by Mycobacterium spp. has recently been recognized as a potentially important clinical problem. However, frequent contamination of mycobacterial cultures by pseudomonads has hampered efforts to define the extent of this problem. This study was done to evaluate current techniques and to establish a more efficient method of recovering mycobacteria from respiratory secretions of patients with cystic fibrosis. Decontamination of respiratory specimens (n = 121) with 0.25% N-acetyl-L-cysteine and 1% sodium hydroxide (NALC-NaOH) was associated with a high rate of pseudomonas overgrowth for both Lowenstein-Jensen slants (74%) and BacTec vials supplemented with PANTA (polymyxin B [50 U/ml], amphotericin B [5 micrograms/ml], nalidixic acid [20 micrograms/ml], trimethoprim [5 micrograms/ml], azlocillin [10 micrograms/ml]) (36%). This overgrowth limited recovery of mycobacteria to only 64% (9 of 14) of specimens positive by smear for acid-fast bacilli (AFB). Decontamination of specimens (n = 441) with NALC-NaOH, followed by 5% oxalic acid treatment, resulted in contamination of only 5% of Lowenstein-Jensen slants and 3% of BacTec vials. AFB were recovered from all 90 AFB smear-positive specimens following the use of this decontamination technique. We recommend that respiratory secretions be decontaminated with NALC-NaOH and oxalic acid to decrease the incidence of Pseudomonas aeruginosa overgrowth. PMID:8463398

  16. Two Human Host Defense Ribonucleases against Mycobacteria, the Eosinophil Cationic Protein (RNase 3) and RNase 7

    PubMed Central

    Pulido, David; Torrent, Marc; Andreu, David; Nogués, M. Victoria

    2013-01-01

    There is an urgent need to develop new agents against mycobacterial infections, such as tuberculosis and other respiratory tract or skin affections. In this study, we have tested two human antimicrobial RNases against mycobacteria. RNase 3, also called the eosinophil cationic protein, and RNase 7 are two small cationic proteins secreted by innate cells during host defense. Both proteins are induced upon infection displaying a wide range of antipathogen activities. In particular, they are released by leukocytes and epithelial cells, contributing to tissue protection. Here, the two RNases have been proven effective against Mycobacterium vaccae at a low micromolar level. High bactericidal activity correlated with their bacterial membrane depolarization and permeabilization activities. Further analysis on both protein-derived peptides identified for RNase 3 an N-terminus fragment that is even more active than the parental protein. Also, a potent bacterial agglutinating activity was unique to RNase 3 and its derived peptide. The particular biophysical properties of the RNase 3 active peptide are envisaged as a suitable reference for the development of novel antimycobacterial drugs. The results support the contribution of secreted RNases to the host immune response against mycobacteria. PMID:23716047

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

    PubMed

    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

  18. Legionella pneumophila Arthritis: use of medium specific for Mycobacteria for isolation of L. pneumophila in culture of articular fluid specimens.

    PubMed

    Bemer, Pascale; Leautez, Sophie; Ninin, Emmanuelle; Jarraud, Sophie; Raffi, François; Drugeon, Henri

    2002-07-01

    We report the first case, to our knowledge, of acute purulent arthritis due to Legionella pneumophila in an immunosuppressed patient. L. pneumophila was isolated from samples of blood and articular fluid cultured with use of medium specific for mycobacteria (Bactec 13A medium).

  19. Legionella pneumophila Arthritis: use of medium specific for Mycobacteria for isolation of L. pneumophila in culture of articular fluid specimens.

    PubMed

    Bemer, Pascale; Leautez, Sophie; Ninin, Emmanuelle; Jarraud, Sophie; Raffi, François; Drugeon, Henri

    2002-07-01

    We report the first case, to our knowledge, of acute purulent arthritis due to Legionella pneumophila in an immunosuppressed patient. L. pneumophila was isolated from samples of blood and articular fluid cultured with use of medium specific for mycobacteria (Bactec 13A medium). PMID:12060893

  20. THE PERSISTENCE OF NONTUBERCULOUS MYCOBACTERIA INI A DRINKING WATER DISTRIBUTION SYSTEM AFTER THE ADDITION OF FILTRATION TREATMENT

    EPA Science Inventory

    There is evidence that drinking water may be a source of pathogenic nontuberculous mycobacteria (NTM) infections in humans. One method by which NTM are believed to enter drinking water distribution systems is by their intracellular colonization of protozoa. Our goal was to determ...

  1. The genealogic tree of mycobacteria reveals a long-standing sympatric life into free-living protozoa.

    PubMed

    Lamrabet, Otmane; Merhej, Vicky; Pontarotti, Pierre; Raoult, Didier; Drancourt, Michel

    2012-01-01

    Free-living protozoa allow horizontal gene transfer with and between the microorganisms that they host. They host mycobacteria for which the sources of transferred genes remain unknown. Using BLASTp, we searched within the genomes of 15 mycobacteria for homologous genes with 34 amoeba-resistant bacteria and the free-living protozoa Dictyostelium discoideum. Subsequent phylogenetic analysis of these sequences revealed that eight mycobacterial open-reading frames (ORFs) were probably acquired via horizontal transfer from beta- and gamma-Proteobacteria and from Firmicutes, but the transfer histories could not be reliably established in details. One further ORF encoding a pyridine nucleotide disulfide oxidoreductase (pyr-redox) placed non-tuberculous mycobacteria in a clade with Legionella spp., Francisella spp., Coxiella burnetii, the ciliate Tetrahymena thermophila and D. discoideum with a high reliability. Co-culturing Mycobacterium avium and Legionella pneumophila with the amoeba Acanthamoeba polyphaga demonstrated that these two bacteria could live together in amoebae for five days, indicating the biological relevance of intra-amoebal transfer of the pyr-redox gene. In conclusion, the results of this study support the hypothesis that protists can serve as a source and a place for gene transfer in mycobacteria.

  2. Growing Plants in School.

    ERIC Educational Resources Information Center

    Salt, Bernard

    1990-01-01

    Background information on the methods and varieties used to demonstrate the cultivation of plants without the use of chemical pesticides is provided. Discussed are species and variety selection, growing plants from seed and from seedlings, soil preparation, using cuttings, useful crops, and pest control. (CW)

  3. GROWING SEEDS, TEACHER'S GUIDE.

    ERIC Educational Resources Information Center

    Elementary Science Study, Newton, MA.

    THIS TEACHER'S GUIDE IS DESIGNED FOR USE WITH AN ELEMENTARY SCIENCE STUDY UNIT, "GROWING SEEDS," IN WHICH SUCH BASIC SCIENCE SKILLS AND PROCESSES AS MEASUREMENT, OBSERVATION, AND HYPOTHESIS FORMATION ARE INTRODUCED THROUGH STUDENT ACTIVITIES INVOLVING SEEDS, GERMINATION, AND SEEDLING GROWTH. THE MATERIALS WERE DEVELOPED FOR USE IN ELEMENTARY…

  4. Growing Up with "1984."

    ERIC Educational Resources Information Center

    Franza, August

    1983-01-01

    Relates changing student reaction to George Orwell's "1984" over 20 years of teaching. Finds present high school students' acceptance of Orwell's bleak world vision both a sign of student honesty and a frightening indication of the growing reality of the book. (MM)

  5. Growing Backyard Textiles

    ERIC Educational Resources Information Center

    Nelson, Eleanor Hall

    1975-01-01

    For those involved in creative work with textiles, the degree of control possible in texture, finish, and color of fiber by growing and processing one's own (perhaps with students' help) can make the experience rewarding. The author describes the processes for flax and nettles and gives tips on necessary equipment. (Author/AJ)

  6. Growing through Literature.

    ERIC Educational Resources Information Center

    Thomas, Barbara J.

    "Growing through Literature" is a curriculum using Joan M. and Erik H. Erikson's theory of the Life Cycle as a structure for selecting and teaching literature to inner-city high school students at Brighton High School in Massachusetts. The program consists of four component parts: Journals, Selected Stories, Discussion, and Autobiography. By…

  7. And Away We Grow!

    ERIC Educational Resources Information Center

    Zeece, Pauline Davey

    1994-01-01

    Notes the difficulty of developing and managing a child care business well. Describes Sharlit and McConnell's (1989) five-phase model of business growth as it might apply to a growing child care program. The phases of development described are creativity; direction; delegation; coordination; and collaboration. (TJQ)

  8. A Growing Phenomenon.

    ERIC Educational Resources Information Center

    Gwynn, Mary Loleta

    1988-01-01

    Describes the "Grow Lab" program which is sponsored by the National Gardening Association. Discusses how eight square feet of classroom space are converted into a mini-ecosystem. Mentions the development of a curriculum guide to accompany the indoor garden. (TW)

  9. Rapid and sensitive identification of Mycobacterium tuberculosis.

    PubMed Central

    Knisley, C V; Damato, J J; McClatchy, J K; Brennan, P J

    1985-01-01

    The fatty acid constituents of 14 species of Mycobacterium (14 isolates) and one isolate each of Corynebacterium xerosis, Nocardia asteroides, and Streptomyces albus were examined with the purpose of distinguishing Mycobacterium tuberculosis from other acid-fast bacilli. Combined thin-layer chromatography (TLC) of methyl mycolates and gas-liquid chromatography (GLC) of shorter-chain fatty acid esters provided an unequivocal identification of M. tuberculosis in a matter of 2 to 3 days. The methodology included rapid and simplified procedures for methanolysis and extraction of bacterial lipids with equally facilitated GLC and TLC analyses. These studies were performed with 0.5 to 1.0 mg of dry bacterial cells (approximately 2.5 X 10(7) CFU). When applied to 100 unknown cultures, the methodology with combined TLC-GLC correctly identified all 49 of the M. tuberculosis-Mycobacterium bovis cultures and a variety of other mycobacterium taxa. It was also interesting to note that 28 of 39 (72%) of the nontuberculous mycobacteria were correctly identified. An additional five species were tentatively identified as belonging to either of two species (Mycobacterium malmoense, Mycobacterium terrae), but in all cases, the two species belonged to the same Runyon group. All six nonmycobacterial species were differentiated from the mycobacteria studied. Images PMID:3932458

  10. Cyclic Amp-Dependent Resuscitation of Dormant Mycobacteria by Exogenous Free Fatty Acids

    PubMed Central

    Shleeva, Margarita; Goncharenko, Anna; Kudykina, Yuliya; Young, Danielle; Young, Michael; Kaprelyants, Arseny

    2013-01-01

    One third of the world population carries a latent tuberculosis (TB) infection, which may reactivate leading to active disease. Although TB latency has been known for many years it remains poorly understood. In particular, substances of host origin, which may induce the resuscitation of dormant mycobacteria, have not yet been described. In vitro models of dormant (“non-culturable”) cells of Mycobacterium smegmatis (mc2155) and Mycobacterium tuberculosis H37Rv were used. We found that the resuscitation of dormant M. smegmatis and M. tuberculosis cells in liquid medium was stimulated by adding free unsaturated fatty acids (FA), including arachidonic acid, at concentrations of 1.6–10 µM. FA addition enhanced cAMP levels in reactivating M. smegmatis cells and exogenously added cAMP (3–10 mM) or dibutyryl-cAMP (0.5–1 mM) substituted for FA, causing resuscitation of M. smegmatis and M. tuberculosis dormant cells. A M. smegmatis null-mutant lacking MSMEG_4279, which encodes a FA-activated adenylyl cyclase (AC), could not be resuscitated by FA but it was resuscitated by cAMP. M. smegmatis and M. tuberculosis cells hyper-expressing AC were unable to form non-culturable cells and a specific inhibitor of AC (8-bromo-cAMP) prevented FA-dependent resuscitation. RT-PCR analysis revealed that rpfA (coding for resuscitation promoting factor A) is up-regulated in M. smegmatis in the beginning of exponential growth following the cAMP increase in lag phase caused by FA-induced cell activation. A specific Rpf inhibitor (4-benzoyl-2-nitrophenylthiocyanate) suppressed FA-induced resuscitation. We propose a novel pathway for the resuscitation of dormant mycobacteria involving the activation of adenylyl cyclase MSMEG_4279 by FAs resulted in activation of cellular metabolism followed later by increase of RpfA activity which stimulates cell multiplication in exponential phase. The study reveals a probable role for lipids of host origin in the resuscitation of dormant mycobacteria

  11. Biosynthesis of D-arabinose in mycobacteria - a novel bacterial pathway with implications for antimycobacterial therapy.

    PubMed

    Wolucka, Beata A

    2008-06-01

    Decaprenyl-phospho-arabinose (beta-D-arabinofuranosyl-1-O-monophosphodecaprenol), the only known donor of d-arabinose in bacteria, and its precursor, decaprenyl-phospho-ribose (beta-D-ribofuranosyl-1-O-monophosphodecaprenol), were first described in 1992. En route to D-arabinofuranose, the decaprenyl-phospho-ribose 2'-epimerase converts decaprenyl-phospho-ribose to decaprenyl-phospho-arabinose, which is a substrate for arabinosyltransferases in the synthesis of the cell-wall arabinogalactan and lipoarabinomannan polysaccharides of mycobacteria. The first step of the proposed decaprenyl-phospho-arabinose biosynthesis pathway in Mycobacterium tuberculosis and related actinobacteria is the formation of D-ribose 5-phosphate from sedoheptulose 7-phosphate, catalysed by the Rv1449 transketolase, and/or the isomerization of d-ribulose 5-phosphate, catalysed by the Rv2465 d-ribose 5-phosphate isomerase. d-Ribose 5-phosphate is a substrate for the Rv1017 phosphoribosyl pyrophosphate synthetase which forms 5-phosphoribosyl 1-pyrophosphate (PRPP). The activated 5-phosphoribofuranosyl residue of PRPP is transferred by the Rv3806 5-phosphoribosyltransferase to decaprenyl phosphate, thus forming 5'-phosphoribosyl-monophospho-decaprenol. The dephosphorylation of 5'-phosphoribosyl-monophospho-decaprenol to decaprenyl-phospho-ribose by the putative Rv3807 phospholipid phosphatase is the committed step of the pathway. A subsequent 2'-epimerization of decaprenyl-phospho-ribose by the heteromeric Rv3790/Rv3791 2'-epimerase leads to the formation of the decaprenyl-phospho-arabinose precursor for the synthesis of the cell-wall arabinans in Actinomycetales. The mycobacterial 2'-epimerase Rv3790 subunit is similar to the fungal D-arabinono-1,4-lactone oxidase, the last enzyme in the biosynthesis of D-erythroascorbic acid, thus pointing to an evolutionary link between the D-arabinofuranose- and L-ascorbic acid-related pathways. Decaprenyl-phospho-arabinose has been a lead compound for the

  12. Macromolecular crystal growing system

    NASA Technical Reports Server (NTRS)

    Snyder, Robert S. (Inventor); Herren, Blair J. (Inventor); Carter, Daniel C. (Inventor); Yost, Vaughn H. (Inventor); Bugg, Charles E. (Inventor); Delucas, Lawrence J. (Inventor); Suddath, Fred L. (Inventor)

    1991-01-01

    A macromolecular crystal growing system especially designed for growing crystals in the low gravity of space as well as the gravity of earth includes at least one tray assembly, a carrier assembly which receives the tray, and a refrigeration-incubation module in which the carrier assembly is received. The tray assembly includes a plurality of sealed chambers with a plastic syringe and a plug means for the double tip of the syringe provided therein. Ganging mechanisms operate the syringes and plugs simultaneously in a precise and smooth operation. Preferably, the tray assemblies are mounted on ball bearing slides for smooth operation in inserting and removing the tray assemblies into the carrier assembly. The plugging mechanism also includes a loading control mechanism. A mechanism for leaving a syringe unplugged is also provided.

  13. Growing up with Retinoblastoma

    ERIC Educational Resources Information Center

    Maley, Tom

    2005-01-01

    An account is given of growing up as a child blinded as a result of a cancer of the eye known as retinoblastoma. The role of his mother is brought out, variously as a source of objective knowledge, of one's personal worth, and of the worth of other people in one's community. The strengths and weaknesses of his first school in his home area and…

  14. How to grow tomatoes.

    PubMed

    Kimura, Seisuke; Sinha, Neelima

    2008-11-01

    INTRODUCTIONTomatoes can be easily grown in a field, in a greenhouse, or in a growth cabinet. They need acidic soil (pH 6.0-6.8), a lot of light, and water. The optimum temperature for growing tomato plants and fruit is 18°C-24°C. This protocol describes how to germinate tomato seeds, cultivate adult plants, and harvest seeds from fruit.

  15. Detection and identification of mycobacteria by amplification of rRNA.

    PubMed

    Böddinghaus, B; Rogall, T; Flohr, T; Blöcker, H; Böttger, E C

    1990-08-01

    Oligonucleotides specific at a genus, group, or species level were defined by a systematic comparison of small-subunit rRNA sequences from Mycobacterium tuberculosis, M. bovis, M. africanum, M. bovis BCG, M. avium, M. kansasii, M. marinum, M. gastri, M. chelonae, M. smegmatis, M. terrae, M. nonchromogenicum, M. xenopi, M. malmoense, M. szulgai, M. scrofulaceum, M. fortuitum, M. gordonae, M. intracellulare, M. simiae, M. flavescens, M. paratuberculosis, M. sphagni, M. cookii, M. komossense, M. phlei, and M. farcinica. On the basis of the defined oligonucleotides, the polymerase chain reaction technique was explored to develop a sensitive taxon-specific detection system for mycobacteria. By using M. tuberculosis as a model system, fewer than 10 bacteria could be reliably detected by this kind of assay. These results suggest that amplification of rRNA sequences by the polymerase chain reaction may provide a highly sensitive and specific tool for the direct detection of microorganisms without the need for prior cultivation.

  16. A rheostat mechanism governs the bifurcation of carbon flux in mycobacteria

    PubMed Central

    Murima, Paul; Zimmermann, Michael; Chopra, Tarun; Pojer, Florence; Fonti, Giulia; Dal Peraro, Matteo; Alonso, Sylvie; Sauer, Uwe; Pethe, Kevin; McKinney, John D.

    2016-01-01

    Fatty acid metabolism is an important feature of the pathogenicity of Mycobacterium tuberculosis during infection. Consumption of fatty acids requires regulation of carbon flux bifurcation between the oxidative TCA cycle and the glyoxylate shunt. In Escherichia coli, flux bifurcation is regulated by phosphorylation-mediated inhibition of isocitrate dehydrogenase (ICD), a paradigmatic example of post-translational mechanisms governing metabolic fluxes. Here, we demonstrate that, in contrast to E. coli, carbon flux bifurcation in mycobacteria is regulated not by phosphorylation but through metabolic cross-activation of ICD by glyoxylate, which is produced by the glyoxylate shunt enzyme isocitrate lyase (ICL). This regulatory circuit maintains stable partitioning of fluxes, thus ensuring a balance between anaplerosis, energy production, and precursor biosynthesis. The rheostat-like mechanism of metabolite-mediated control of flux partitioning demonstrates the importance of allosteric regulation during metabolic steady-state. The sensitivity of this regulatory mechanism to perturbations presents a potentially attractive target for chemotherapy. PMID:27555519

  17. Association of mycobacteria in recirculating aquaculture systems and mycobacterial disease in fish.

    PubMed

    Yanong, Roy P E; Pouder, Deborah B; Falkinham, Joseph O

    2010-12-01

    Mycobacterium marinum isolates cultivated from tissue containing granulomatous lesions in Florida pompano Trachinotus carolinus and from biofilm samples collected from their tank and water recirculating system had identical (L1 of 11 bands) repetitive-sequence-based polymerase chain reaction (rep-PCR) DNA fingerprints. A second M. marinum clone sharing 4 of 11 rep-PCR bands with the first clone was isolated from some fish tissues but not from system samples. Water samples yielded low numbers of colonies of mycobacteria (0.08-1.3/mL), but high numbers were recovered from biofilms (260-12,000/swab) and filters (63-21,000/ filter). Mycobacterium hemophilum, M. chelonae, M. trivale, M. gastri, and M. gordonae were isolated from system samples alone.

  18. A rheostat mechanism governs the bifurcation of carbon flux in mycobacteria.

    PubMed

    Murima, Paul; Zimmermann, Michael; Chopra, Tarun; Pojer, Florence; Fonti, Giulia; Dal Peraro, Matteo; Alonso, Sylvie; Sauer, Uwe; Pethe, Kevin; McKinney, John D

    2016-01-01

    Fatty acid metabolism is an important feature of the pathogenicity of Mycobacterium tuberculosis during infection. Consumption of fatty acids requires regulation of carbon flux bifurcation between the oxidative TCA cycle and the glyoxylate shunt. In Escherichia coli, flux bifurcation is regulated by phosphorylation-mediated inhibition of isocitrate dehydrogenase (ICD), a paradigmatic example of post-translational mechanisms governing metabolic fluxes. Here, we demonstrate that, in contrast to E. coli, carbon flux bifurcation in mycobacteria is regulated not by phosphorylation but through metabolic cross-activation of ICD by glyoxylate, which is produced by the glyoxylate shunt enzyme isocitrate lyase (ICL). This regulatory circuit maintains stable partitioning of fluxes, thus ensuring a balance between anaplerosis, energy production, and precursor biosynthesis. The rheostat-like mechanism of metabolite-mediated control of flux partitioning demonstrates the importance of allosteric regulation during metabolic steady-state. The sensitivity of this regulatory mechanism to perturbations presents a potentially attractive target for chemotherapy. PMID:27555519

  19. The role of Mycobacteria Other Than Tuberculosis (MOTT) in patients with cystic fibrosis.

    PubMed

    Hjelt, K; Højlyng, N; Howitz, P; Illum, N; Munk, E; Valerius, N H; Fursted, K; Hansen, K N; Heltberg, I; Koch, C

    1994-01-01

    The purpose of this study was to estimate the frequency of and evaluate the clinical impact of pulmonary mycobacterial infections among cystic fibrosis (CF) patients. 185 CF patients aged 2.2-38.5 years were screened by sputum samples and by intracutaneous skin tests against tuberculin and sensitins produced from Mycobacterium chelonae subsp. abscessus, M. avium, M. intracellulare and M. scrofulaceum (the MAIS complex). The skin tests towards the sensitins in BCG-vaccinated patients (n = 60) were significantly influenced by the vaccination. 26 of the remaining 125 non-vaccinated patients had > or = 1 positive skin test (95% confidence limits 15-29%). The majority reacted against the MAIS complex. However, the reactions were similar to those of healthy siblings and an age-matched control group. Moreover, the lung function, growth and HbA1c were similar among skin test positive and negative patients. Three patients had repeated positive sputum cultures, the point prevalence being 1.6% (M. intracellulare, n = 2 and M. chelonae subsp. abscessus, n = 1). During the subsequent 4 years, 4 additional patients with M. chelonae subsp. abscessus were identified. Based on clinical observations, 5 of the infected patients were considered asymptomatic, while 2 might have been symptomatic. In 1 patient, M. chelonae subsp. abscessus disappeared spontaneously. Despite intensive treatment with new antibiotics against Mycobacteria Other Than Tuberculosis (MOTT) in 4 patients, the mycobacteria were not eradicated. In conclusion, MOTT infection was rare and the clinical impact difficult to prove. Treatment should focus on clinical improvement in the individual patient suspected of suffering from significant symptomatic infection. Eradication of the bacteria should not be expected. PMID:7855554

  20. [Evaluation of DNA-DNA hybridization method for identification of mycobacteria using a colorimetric microplate kit].

    PubMed

    Yamazaki, T; Takahashi, H; Nakamura, R M

    1993-01-01

    DNA-DNA hybridization was applied for identification of mycobacteria and developed as a kit "microplate hybridization kit" (refers to MPHD) by Kobayashi Pharmaceutical Co. We received test samples of the microplates from the company and examined them for their and reliability using 180 mycobacterial strains of 21 species kept in our laboratory. The results of identification by MPHD were 100% identical to those of biochemical identification in the type or reference strains of mycobacteria, showing good reliability of MPHD method. Among clinical isolates, there were six M. tuberculosis strains which did not show typical characteristics for M. tuberculosis, i.e., niacin test negative or nitrate reduction weak positive, but all of these were identified as M. tuberculosis complex by MPHD method. Some strains from clinical isolates showed difference in identification between MPHD and biochemical methods: M. avium complex, identified biochemically were divided into M. avium and M. intracellulare by MPHD, M. fortuitum complex by biochemical identification were distinguished as M. fortuitum and M. chelonae by MPHD. Further, M. chelonae were separated into M. chelonae subsp. chelonae and M. chelonae subsp. abscessus by MPHD. M. peregrinum has been considered as a synonym of M. fortuitum, but we could distinguish M. peregrinum from M. fortuitum clearly by MPHD method. Thus, it is suggested that M. peregrinum and M. fortuitum are different species. Keys for getting reliable results using the MPHD kit are: (1) appropriate amount of bacteria for use, (2) purification of DNA, (3) enough deproteinization, and (4) appropriate timing to read colorimetry measurement of the plate. PMID:8437424

  1. WHO Co-operative studies on a simple culture technique for the isolation of mycobacteria

    PubMed Central

    Šula, Ladislav

    1963-01-01

    Tuberculosis surveys are in progress in many countries that do not have adequate laboratory facilities for carrying out complicated bacteriological procedures. As part of a WHO co-operative research programme, studies have been undertaken with a view to developing a simple culture technique for the isolation of mycobacteria that does not require elaborate equipment. This paper is the first report on these co-operative studies. Storage and transport are known to affect adversely the viability of Mycobacterium tuberculosis in pathological specimens, thus giving rise to poor culture results and indicating the advisability of culturing such specimens on the spot. The preparation of the efficient and widely used Löwenstein-Jensen (L-J) culture medium, however, requires materials and facilities that are not easy available in developing countries. In an attempt to overcome this difficulty, the Tuberculosis Research Institute in Prague has developed a semi-synthetic liquid medium that can be prepared in bulk, concentrated and lyophilized, and sent even to distant laboratories. The present paper describes in detail the preparation of this lyophilized medium, which can be stored at room temperature for at least 6-12 months and is easy to reconstitute, and discusses the growth characteristics of mycobacteria multiplied in it. Experience in Czechoslovakia, where between 1953 and 1962 nearly 21 million cultures have been made with the medium, has shown that it is quite satisfactory and even slightly superior to L-J medium in certain respects. ImagesFIG. 1FIG. 2FIG. 3 & 4FIG. 9FIG. 10FIG. 11FIG. 12FIG. 5FIG. 6FIG. 7FIG. 8FIG. 13FIG. 14FIG. 15FIG. 16 PMID:14102036

  2. Maturation of Innate Responses to Mycobacteria over the First 9 Months of Life

    PubMed Central

    Shey, Muki S.; Nemes, Elisa; Whatney, Wendy; de Kock, Marwou; Africa, Hadn; Barnard, Charlene; van Rooyen, Michele; Stone, Lynnette; Riou, Catherine; Kollmann, Tobias; Hawn, Thomas R.; Scriba, Thomas J.; Hanekom, Willem A.

    2014-01-01

    Newborns and young infants are particularly susceptible to infections, including Mycobacterium tuberculosis. Further, immunogenicity of vaccines against tuberculosis and other infectious diseases appears suboptimal early in life, compared with later in life. We hypothesized that developmental changes in innate immunity would underlie these observations. To determine evolution of innate responses to mycobacteria early in life, whole blood from newborns, 10-week old and 36-week old infants was incubated with viable Mycobacterium bovis Bacille Calmette Guerin (BCG) or TLR ligands. Innate cell expression of cytokines and maturation markers was assessed, as well as activation of the pro-inflammatory NF-κB and MAPK signaling pathways. BCG-induced production of pro-inflammatory cytokines TNF-α, IL-6 and IL-12p40 increased from the newborn period to 9 months of age in monocytes, but not in myeloid dendritic cells (mDCs). No changes in production of anti-inflammatory IL-10 were observed. CD40 expression increased with age in both cell populations. Older infants displayed substantial activation of all three signal transduction molecules: degradation of NF-κB inhibitor IκBα and phosphorylation of MAPK Erk and p38 upon TLR1/2 triggering, compared with predominant activation of only one of any of these molecules in newborns. Maturation of innate pro-inflammatory responses during the first 9 months of life may underlie more effective control of mycobacteria and other pathogens observed later in infancy, and age-related differential induction of Th1 responses by vaccination. PMID:24733845

  3. Geothermal Grows Up

    ERIC Educational Resources Information Center

    Johnson, William C.; Kraemer, Steven; Ormond, Paul

    2011-01-01

    Self-declared energy and carbon reduction goals on the part of progressive colleges and universities have driven ground source geothermal space heating and cooling systems into rapid evolution, as part of long-term climate action planning efforts. The period of single-building or single-well solutions is quickly being eclipsed by highly engineered…

  4. Halogenated graphenes: rapidly growing family of graphene derivatives.

    PubMed

    Karlický, František; Kumara Ramanatha Datta, Kasibhatta; Otyepka, Michal; Zbořil, Radek

    2013-08-27

    Graphene derivatives containing covalently bound halogens (graphene halides) represent promising two-dimensional systems having interesting physical and chemical properties. The attachment of halogen atoms to sp(2) carbons changes the hybridization state to sp(3), which has a principal impact on electronic properties and local structure of the material. The fully fluorinated graphene derivative, fluorographene (graphene fluoride, C1F1), is the thinnest insulator and the only stable stoichiometric graphene halide (C1X1). In this review, we discuss structural properties, syntheses, chemistry, stabilities, and electronic properties of fluorographene and other partially fluorinated, chlorinated, and brominated graphenes. Remarkable optical, mechanical, vibrational, thermodynamic, and conductivity properties of graphene halides are also explored as well as the properties of rare structures including multilayered fluorinated graphenes, iodine-doped graphene, and mixed graphene halides. Finally, patterned halogenation is presented as an interesting approach for generating materials with applications in the field of graphene-based electronic devices.

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

    USGS Publications Warehouse

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

    2005-01-01

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

  6. Growing Unculturable Bacteria

    PubMed Central

    2012-01-01

    The bacteria that can be grown in the laboratory are only a small fraction of the total diversity that exists in nature. At all levels of bacterial phylogeny, uncultured clades that do not grow on standard media are playing critical roles in cycling carbon, nitrogen, and other elements, synthesizing novel natural products, and impacting the surrounding organisms and environment. While molecular techniques, such as metagenomic sequencing, can provide some information independent of our ability to culture these organisms, it is essentially impossible to learn new gene and pathway functions from pure sequence data. A true understanding of the physiology of these bacteria and their roles in ecology, host health, and natural product production requires their cultivation in the laboratory. Recent advances in growing these species include coculture with other bacteria, recreating the environment in the laboratory, and combining these approaches with microcultivation technology to increase throughput and access rare species. These studies are unraveling the molecular mechanisms of unculturability and are identifying growth factors that promote the growth of previously unculturable organisms. This minireview summarizes the recent discoveries in this area and discusses the potential future of the field. PMID:22661685

  7. Guidelines for growing perennial grasses for biofuel and bioproducts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Guidelines for growing perennial grasses for biofuel and bioproducts Rob Mitchell Abstract: Switchgrass, big bluestem, and warm-season grass mixtures provide numerous benefits. Existing field equipment, herbicides, and cultivar improvement promote rapid establishment in the planting year. These gra...

  8. How do normal faults grow?

    NASA Astrophysics Data System (ADS)

    Jackson, Christopher; Bell, Rebecca; Rotevatn, Atle; Tvedt, Anette

    2016-04-01

    Normal faulting accommodates stretching of the Earth's crust, and it is arguably the most fundamental tectonic process leading to continent rupture and oceanic crust emplacement. Furthermore, the incremental and finite geometries associated with normal faulting dictate landscape evolution, sediment dispersal and hydrocarbon systems development in rifts. Displacement-length scaling relationships compiled from global datasets suggest normal faults grow via a sympathetic increase in these two parameters (the 'isolated fault model'). This model has dominated the structural geology literature for >20 years and underpins the structural and tectono-stratigraphic models developed for active rifts. However, relatively recent analysis of high-quality 3D seismic reflection data suggests faults may grow by rapid establishment of their near-final length prior to significant displacement accumulation (the 'coherent fault model'). The isolated and coherent fault models make very different predictions regarding the tectono-stratigraphic evolution of rift basin, thus assessing their applicability is important. To-date, however, very few studies have explicitly set out to critically test the coherent fault model thus, it may be argued, it has yet to be widely accepted in the structural geology community. Displacement backstripping is a simple graphical technique typically used to determine how faults lengthen and accumulate displacement; this technique should therefore allow us to test the competing fault models. However, in this talk we use several subsurface case studies to show that the most commonly used backstripping methods (the 'original' and 'modified' methods) are, however, of limited value, because application of one over the other requires an a priori assumption of the model most applicable to any given fault; we argue this is illogical given that the style of growth is exactly what the analysis is attempting to determine. We then revisit our case studies and demonstrate

  9. Sleep to grow smart?

    PubMed

    Volk, Carina; Huber, Reto

    2015-01-01

    Sleep is undisputable an essential part of our life, if we do not sleep enough we feel the consequences the next day. The importance of sleep for healthy brain functioning has been well studied in adults, but less is known for the role of sleep in the paediatric age. Childhood and adolescence is a critical phase for brain development. The increased need for sleep during this developmental phase fosters the growing recognition for a central role of sleep during development. In this review we summarize the findings that demonstrate a close relationship between sleep and brain maturation, discuss the consequences of insufficient sleep during childhood and adolescence and outline initial attempts that have been made in order to improve sleep in this age range. PMID:26742664

  10. Growing a market economy

    SciTech Connect

    Basu, N.; Pryor, R.J.

    1997-09-01

    This report presents a microsimulation model of a transition economy. Transition is defined as the process of moving from a state-enterprise economy to a market economy. The emphasis is on growing a market economy starting from basic microprinciples. The model described in this report extends and modifies the capabilities of Aspen, a new agent-based model that is being developed at Sandia National Laboratories on a massively parallel Paragon computer. Aspen is significantly different from traditional models of the economy. Aspen`s emphasis on disequilibrium growth paths, its analysis based on evolution and emergent behavior rather than on a mechanistic view of society, and its use of learning algorithms to simulate the behavior of some agents rather than an assumption of perfect rationality make this model well-suited for analyzing economic variables of interest from transition economies. Preliminary results from several runs of the model are included.

  11. Universal stress protein Rv2624c alters abundance of arginine and enhances intracellular survival by ATP binding in mycobacteria

    PubMed Central

    Jia, Qiong; Hu, Xinling; Shi, Dawei; Zhang, Yan; Sun, Meihao; Wang, Jianwei; Mi, Kaixia; Zhu, Guofeng

    2016-01-01

    The universal stress protein family is a family of stress-induced proteins. Universal stress proteins affect latency and antibiotic resistance in mycobacteria. Here, we showed that Mycobacterium smegmatis overexpressing M. tuberculosis universal stress protein Rv2624c exhibits increased survival in human monocyte THP-1 cells. Transcriptome analysis suggested that Rv2624c affects histidine metabolism, and arginine and proline metabolism. LC-MS/MS analysis showed that Rv2624c affects the abundance of arginine, a modulator of both mycobacteria and infected THP-1 cells. Biochemical analysis showed that Rv2624c is a nucleotide-binding universal stress protein, and an Rv2624c mutant incapable of binding ATP abrogated the growth advantage in THP-1 cells. Rv2624c may therefore modulate metabolic pathways in an ATP-dependent manner, changing the abundance of arginine and thus increasing survival in THP-1 cells. PMID:27762279

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

    PubMed

    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.

  13. [Distribution of nontuberculous mycobacteria isolated from clinical specimens and identified with DNA sequence analysis].

    PubMed

    Özçolpan, O Olcay; Sürücüoğlu, Süheyla; Özkütük, Nuri; Çavuşoğlu, Cengiz

    2015-10-01

    The aims of the study were to perform the identification of nontuberculous mycobacteria (NTM) isolated from different clinical specimens in the Mycobacteriology Laboratory of Celal Bayar University, Manisa (located at Aegean region of Turkey), by DNA sequence analysis, and to discuss the epidemiological aspects of the data obtained. Out of 5122 clinical specimens sent to the laboratory with the initial diagnosis of tuberculosis in the period April 2007 to July 2011, M.tuberculosis complex and NTM were identified in 225 (4.39%) and 126 (2.46%) samples, respectively. DNA sequence analysis by targeting hsp65 and 16S rDNA gene regions was performed on 101 of the NTM strains in Mycobacteriology Laboratory of Ege University, Izmir. DNA sequence analysis data was evaluated using RIDOM and GenBLAST data bases. NTM strains were identified as 40 M.porcinum (39.60%), 36 M.lentiflavum (35.65%), six M.abscessus (5.64%), five M.peregrinum (4.95%), four M.gordonae (3.96%), three M.fortuitum (2.97%), two M.chelonae (1.98%), and one for each M.alvei (0.99%), M.scrofulaceum (0.99%), M.kansasii (0.99%) species. Two strains which were both 95-98% compatible with other mycobacteria in the data bases could not be identified with certainty. Seventy-two (94.73%) strains of M.lentiflavum and M.porcinum, which were the most frequent (75.24%) species in the study, were isolated from bronchoalveolar lavage (BAL) specimens. The remaining 99 strains examined could not be proven as the cause of the disease due to absence of patients' clinical data, whereas two M.abscessus strains isolated from the sputum were considered as the cause of the disease according to the ATS/IDSA criteria. The isolation rate of NTM in 2010 was found significantly higher (5.33%) than previous years. Review of the 2010 data showed that all strains of M.porcinum and M.lentiflavum, which were the most frequently identified strains were isolated from BAL specimens. This situation is in line with the start of using of an

  14. [Distribution of nontuberculous mycobacteria isolated from clinical specimens and identified with DNA sequence analysis].

    PubMed

    Özçolpan, O Olcay; Sürücüoğlu, Süheyla; Özkütük, Nuri; Çavuşoğlu, Cengiz

    2015-10-01

    The aims of the study were to perform the identification of nontuberculous mycobacteria (NTM) isolated from different clinical specimens in the Mycobacteriology Laboratory of Celal Bayar University, Manisa (located at Aegean region of Turkey), by DNA sequence analysis, and to discuss the epidemiological aspects of the data obtained. Out of 5122 clinical specimens sent to the laboratory with the initial diagnosis of tuberculosis in the period April 2007 to July 2011, M.tuberculosis complex and NTM were identified in 225 (4.39%) and 126 (2.46%) samples, respectively. DNA sequence analysis by targeting hsp65 and 16S rDNA gene regions was performed on 101 of the NTM strains in Mycobacteriology Laboratory of Ege University, Izmir. DNA sequence analysis data was evaluated using RIDOM and GenBLAST data bases. NTM strains were identified as 40 M.porcinum (39.60%), 36 M.lentiflavum (35.65%), six M.abscessus (5.64%), five M.peregrinum (4.95%), four M.gordonae (3.96%), three M.fortuitum (2.97%), two M.chelonae (1.98%), and one for each M.alvei (0.99%), M.scrofulaceum (0.99%), M.kansasii (0.99%) species. Two strains which were both 95-98% compatible with other mycobacteria in the data bases could not be identified with certainty. Seventy-two (94.73%) strains of M.lentiflavum and M.porcinum, which were the most frequent (75.24%) species in the study, were isolated from bronchoalveolar lavage (BAL) specimens. The remaining 99 strains examined could not be proven as the cause of the disease due to absence of patients' clinical data, whereas two M.abscessus strains isolated from the sputum were considered as the cause of the disease according to the ATS/IDSA criteria. The isolation rate of NTM in 2010 was found significantly higher (5.33%) than previous years. Review of the 2010 data showed that all strains of M.porcinum and M.lentiflavum, which were the most frequently identified strains were isolated from BAL specimens. This situation is in line with the start of using of an

  15. Fungus-growing ants.

    PubMed

    Weber, N A

    1966-08-01

    Fungus-growing ants (Attini) are in reality unique fungus-culturing insects.There are several hundred species in some dozen genera, of which Acromyrmex and Atta are the conspicuous leaf-cutters. The center of their activities is the fungus garden, which is also the site of the queen and brood. The garden, in most species, is made from fresh green leaves or other vegetal material. The ants forage for this, forming distinct trails to the vegetation that is being harvested. The cut leaves or other substrate are brought into the nest and prepared for the fungus. Fresh leaves and flowers are cut into pieces a millimeter or two in diameter; the ants form them into a pulpy mass by pinching them with the mandibles and adding saliva. Anal droplets are deposited on the pieces, which are then forced into place in the garden. Planting of the fungus is accomplished by an ant's picking up tufts of the adjacent mycelium and dotting the surface of the new substrate with it. The combination of salivary and anal secretions, together with the constant care given by the ants, facilitates the growth of the ant fungus only, despite constant possibilities for contamination. When the ants are removed, alien fungi and other organisms flourish. A mature nest of Atta Sexdens may consist of 2000 chambers, some temporarily empty, some with refuse, and the remainder with fungus gardens. Thousands of kilograms of fresh leaves will have been used. A young laboratory colony of Atta cephalotes will use 1 kilogram of fresh leaves for one garden. The attines are the chief agents for introducing organic matter into the soil in tropical rain forests; this matter becomes the nucleus for a host of other organisms, including nematodes and arthropods, after it is discarded by the ants. One ant species cultures a yeast; all others grow a mycelium. In the higher species the mycelium forms clusters of inflated hyphae. Mycologists accept as valid two names for confirmed fruiting stages: Leucocoprinus ( or

  16. Use of BACTEC MGIT 960 for recovery of mycobacteria from clinical specimens: multicenter study.

    PubMed

    Tortoli, E; Cichero, P; Piersimoni, C; Simonetti, M T; Gesu, G; Nista, D

    1999-11-01

    The BACTEC MGIT 960 instrument is a fully automated system that exploits the fluorescence of an oxygen sensor to detect growth of mycobacteria in culture. Its performance was compared to those of the radiometric BACTEC 460 instrument and egg-based Lowenstein-Jensen medium. An identical volume of sample was inoculated in different media, and incubation was carried out for 6 weeks with the automatic systems and for 8 weeks on solid media. A total of 2,567 specimens obtained from 1,631 patients were cultured in parallel. Mycobacteria belonging to nine different taxa were isolated by at least one of the culture systems, with 75% of them being represented by Mycobacterium tuberculosis complex. The best yield was obtained with the BACTEC 460 system, with 201 isolates, in comparison with 190 isolates with the BACTEC MGIT 960 system and 168 isolates with Lowenstein-Jensen medium. A similar but not significant difference was obtained when the most-represented organisms, the M. tuberculosis complex, Mycobacterium xenopi, and the Mycobacterium avium complex, were analyzed separately and when combinations of a solid medium with the BACTEC MGIT 960 system and with the BACTEC 460 system were considered. The shortest times to detection were obtained with the BACTEC MGIT 960 system (13.3 days); 1.5 days earlier than that with the BACTEC 460 system (14.8 days) and 12 days earlier than that with Lowenstein-Jensen medium (25.6 days). The BACTEC MGIT 960 system had a contamination rate of 10.0%, intermediate between those of the radiometric system (3.7%) and the egg-based medium (17.0%). We conclude, therefore, that the BACTEC MGIT 960 system is a fully automated, nonradiometric instrument that is suitable for the detection of growth of tuberculous and other mycobacterial species and that is characterized by detection times that are even shorter than that of the "gold standard," the BACTEC 460 system. The contamination rate was higher than that for the radiometric BACTEC 460 system

  17. Growing for different ends.

    PubMed

    Catts, Oron; Zurr, Ionat

    2014-11-01

    Tissue engineering and regenerative biology are usually discussed in relation to biomedical research and applications. However, hand in hand with developments of this field in the biomedical context, other approaches and uses for non-medical ends have been explored. There is a growing interest in exploring spin off tissue engineering and regenerative biology technologies in areas such as consumer products, art and design. This paper outlines developments regarding in vitro meat and leather, actuators and bio-mechanic interfaces, speculative design and contemporary artistic practices. The authors draw on their extensive experience of using tissue engineering for non-medical ends to speculate about what lead to these applications and their possible future development and uses. Avoiding utopian and dystopian postures and using the notion of the contestable, this paper also mentions some philosophical and ethical consideration stemming from the use of non-medical approaches to tissue constructs. This article is part of a directed issue entitled: Regenerative Medicine: the challenge of translation.

  18. Growing for different ends.

    PubMed

    Catts, Oron; Zurr, Ionat

    2014-11-01

    Tissue engineering and regenerative biology are usually discussed in relation to biomedical research and applications. However, hand in hand with developments of this field in the biomedical context, other approaches and uses for non-medical ends have been explored. There is a growing interest in exploring spin off tissue engineering and regenerative biology technologies in areas such as consumer products, art and design. This paper outlines developments regarding in vitro meat and leather, actuators and bio-mechanic interfaces, speculative design and contemporary artistic practices. The authors draw on their extensive experience of using tissue engineering for non-medical ends to speculate about what lead to these applications and their possible future development and uses. Avoiding utopian and dystopian postures and using the notion of the contestable, this paper also mentions some philosophical and ethical consideration stemming from the use of non-medical approaches to tissue constructs. This article is part of a directed issue entitled: Regenerative Medicine: the challenge of translation. PMID:25286303

  19. How Do Galaxies Grow?

    NASA Astrophysics Data System (ADS)

    2008-08-01

    Astronomers have caught multiple massive galaxies in the act of merging about 4 billion years ago. This discovery, made possible by combining the power of the best ground- and space-based telescopes, uniquely supports the favoured theory of how galaxies form. ESO PR Photo 24/08 ESO PR Photo 24/08 Merging Galaxies in Groups How do galaxies form? The most widely accepted answer to this fundamental question is the model of 'hierarchical formation', a step-wise process in which small galaxies merge to build larger ones. One can think of the galaxies forming in a similar way to how streams merge to form rivers, and how these rivers, in turn, merge to form an even larger river. This theoretical model predicts that massive galaxies grow through many merging events in their lifetime. But when did their cosmological growth spurts finish? When did the most massive galaxies get most of their mass? To answer these questions, astronomers study massive galaxies in clusters, the cosmological equivalent of cities filled with galaxies. "Whether the brightest galaxies in clusters grew substantially in the last few billion years is intensely debated. Our observations show that in this time, these galaxies have increased their mass by 50%," says Kim-Vy Tran from the University of Zürich, Switzerland, who led the research. The astronomers made use of a large ensemble of telescopes and instruments, including ESO's Very Large Telescope (VLT) and the Hubble Space Telescope, to study in great detail galaxies located 4 billion light-years away. These galaxies lie in an extraordinary system made of four galaxy groups that will assemble into a cluster. In particular, the team took images with VIMOS and spectra with FORS2, both instruments on the VLT. From these and other observations, the astronomers could identify a total of 198 galaxies belonging to these four groups. The brightest galaxies in each group contain between 100 and 1000 billion of stars, a property that makes them comparable

  20. Growing Galaxies Gently

    NASA Astrophysics Data System (ADS)

    2010-10-01

    New observations from ESO's Very Large Telescope have, for the first time, provided direct evidence that young galaxies can grow by sucking in the cool gas around them and using it as fuel for the formation of many new stars. In the first few billion years after the Big Bang the mass of a typical galaxy increased dramatically and understanding why this happened is one of the hottest problems in modern astrophysics. The results appear in the 14 October issue of the journal Nature. The first galaxies formed well before the Universe was one billion years old and were much smaller than the giant systems - including the Milky Way - that we see today. So somehow the average galaxy size has increased as the Universe has evolved. Galaxies often collide and then merge to form larger systems and this process is certainly an important growth mechanism. However, an additional, gentler way has been proposed. A European team of astronomers has used ESO's Very Large Telescope to test this very different idea - that young galaxies can also grow by sucking in cool streams of the hydrogen and helium gas that filled the early Universe and forming new stars from this primitive material. Just as a commercial company can expand either by merging with other companies, or by hiring more staff, young galaxies could perhaps also grow in two different ways - by merging with other galaxies or by accreting material. The team leader, Giovanni Cresci (Osservatorio Astrofisico di Arcetri) says: "The new results from the VLT are the first direct evidence that the accretion of pristine gas really happened and was enough to fuel vigorous star formation and the growth of massive galaxies in the young Universe." The discovery will have a major impact on our understanding of the evolution of the Universe from the Big Bang to the present day. Theories of galaxy formation and evolution may have to be re-written. The group began by selecting three very distant galaxies to see if they could find evidence

  1. Calcaneal Osteomyelitis due to Non-tuberculous Mycobacteria: A Case Report

    PubMed Central

    Yi, Tae-Im; Choe, Yeo-Reum; Kim, Joo-Sup; Kwon, Kye-Won

    2016-01-01

    Osteomyelitis is a bone infection caused by bacteria or other germs. Gram-positive cocci are the most common etiological organisms of calcaneal osteomyelitis; whereas, non-tuberculous mycobacteria (NTM) are rarely documented. We reported a case of NTM calcaneal osteomyelitis in a 51-year-old female patient. She had been previously treated in many local clinics with multiple local steroid injection over 50 times and extracorporeal shock-wave therapy over 20 times with the impression of plantar fasciitis for 3 years prior. Diagnostic workup revealed a calcaneal osteomyelitis and polymerase chain reaction assay on bone aspirate specimens confirmed the diagnosis of non-tuberculous mycobacterial osteomyelitis. The patient had a partial calcanectomy with antitubercular therapy. Six months after surgery, a follow-up magnetic resonance imaging showed localized chronic osteomyelitis with abscess formation. We continued anti-tubercular therapy without operation. At 18-month follow-up after surgery and comprehensive rehabilitation therapy, she was ambulating normally and able to carry out her daily activities without any discomfort. PMID:26949685

  2. Species Identification and Clarithromycin Susceptibility Testing of 278 Clinical Nontuberculosis Mycobacteria Isolates.

    PubMed

    Nie, Wenjuan; Duan, Hongfei; Huang, Hairong; Lu, Yu; Chu, Naihui

    2015-01-01

    Purpose of this paper is to analyze different species' proportion of nontuberculosis mycobacteria (NTM) and susceptibility to clarithromycin of different species. 278 clinical NTM isolates were identified into species by using 16S rRNA, rpoB and hsp65. Then clarithromycin susceptibility testing against different species was done separately, using microplate Alamar Blue assay. Finally, resistance isolates' erm(41) of M. abscessus were sequenced in order to analyze mechanisms for clarithromycin resistant. In this test, 131 isolates (47%) belonged to M. avium complex (MAC), and 70 isolates (25%) belonged to M. abscessus. Nearly all the M. abscessus subsp. abscessus resistant to clarithromycin had T28 in erm(41). However, all the M. abscessus subsp. abscessus susceptible to clarithromycin had C28 in erm(41). In this study, we find that MAC was the most common pathogens of NTM, and the second one was M. abscessus. However, M. chelonei, M. fuerth, and M. gordon were rare. Clarithromycin had a good inhibition activity against all the NTM species except M. abscessus subsp. abscessus. The erm(41) genotype is of high relevance to clarithromycin resistance. PMID:26146620

  3. Species Identification and Clarithromycin Susceptibility Testing of 278 Clinical Nontuberculosis Mycobacteria Isolates

    PubMed Central

    Nie, Wenjuan; Duan, Hongfei; Huang, Hairong; Lu, Yu; Chu, Naihui

    2015-01-01

    Purpose of this paper is to analyze different species' proportion of nontuberculosis mycobacteria (NTM) and susceptibility to clarithromycin of different species. 278 clinical NTM isolates were identified into species by using 16S rRNA, rpoB and hsp65. Then clarithromycin susceptibility testing against different species was done separately, using microplate Alamar Blue assay. Finally, resistance isolates' erm(41) of M. abscessus were sequenced in order to analyze mechanisms for clarithromycin resistant. In this test, 131 isolates (47%) belonged to M. avium complex (MAC), and 70 isolates (25%) belonged to M. abscessus. Nearly all the M. abscessus subsp. abscessus resistant to clarithromycin had T28 in erm(41). However, all the M. abscessus subsp. abscessus susceptible to clarithromycin had C28 in erm(41). In this study, we find that MAC was the most common pathogens of NTM, and the second one was M. abscessus. However, M. chelonei, M. fuerth, and M. gordon were rare. Clarithromycin had a good inhibition activity against all the NTM species except M. abscessus subsp. abscessus. The erm(41) genotype is of high relevance to clarithromycin resistance. PMID:26146620

  4. Culture-Independent Identification of Nontuberculous Mycobacteria in Cystic Fibrosis Respiratory Samples

    PubMed Central

    Caverly, Lindsay J.; Carmody, Lisa A.; Haig, Sarah-Jane; Kotlarz, Nadine; Kalikin, Linda M.; Raskin, Lutgarde; LiPuma, John J.

    2016-01-01

    Respiratory tract infections with nontuberculous mycobacteria (NTM) are increasing in prevalence and are a significant cause of lung function decline in individuals with cystic fibrosis (CF). NTM have been detected in culture-independent analyses of CF airway microbiota at lower rates than would be expected based on published prevalence data, likely due to poor lysing of the NTM cell wall during DNA extraction. We compared a standard bacterial lysis protocol with a modified method by measuring NTM DNA extraction by qPCR and NTM detection with bacterial 16S rRNA gene sequencing. The modified method improved NTM DNA recovery from spiked CF sputum samples by a mean of 0.53 log10 copies/mL for M. abscessus complex and by a mean of 0.43 log10 copies/mL for M. avium complex as measured by qPCR targeting the atpE gene. The modified method also improved DNA sequence based NTM detection in NTM culture-positive CF sputum and bronchoalveolar lavage samples; however, both qPCR and 16S rRNA gene sequencing remained less sensitive than culture for NTM detection. We highlight the limitations of culture-independent identification of NTM from CF respiratory samples, and illustrate how alterations in the bacterial lysis and DNA extraction process can be employed to improve NTM detection with both qPCR and 16S rRNA gene sequencing. PMID:27093603

  5. Studies of inositol 1-phosphate analogues as inhibitors of the phosphatidylinositol phosphate synthase in mycobacteria.

    PubMed

    Morii, Hiroyuki; Okauchi, Tatsuo; Nomiya, Hiroki; Ogawa, Midori; Fukuda, Kazumasa; Taniguchi, Hatsumi

    2013-03-01

    We previously reported a novel pathway for the biosynthesis of phosphatidylinositol in mycobacteria via phosphatidylinositol phosphate (PIP) [Morii H., Ogawa, M., Fukuda, K., Taniguchi, H., and Koga, Y (2010) J. Biochem. 148, 593-602]. PIP synthase in the pathway is a promising target for the development of new anti-mycobacterium drugs. In the present study, we evaluated the characteristics of the PIP synthase of Mycobacterium tuberculosis. Four types of compounds were chemically synthesized based on the assumption that structural homologues of inositol 1-phosphate, a PIP synthase substrate, would act as PIP synthase inhibitors, and the results confirmed that all synthesized compounds inhibited PIP synthase activity. The phosphonate analogue of inositol 1-phosphate (Ino-C-P) had the greatest inhibitory effect among the synthesized compounds examined. Kinetic analysis indicated that Ino-C-P acted as a competitive inhibitor of inositol 1-phosphate. The IC(50) value for Ino-C-P inhibition of the PIP synthase activity was estimated to be 2.0 mM. Interestingly, Ino-C-P was utilized in the same manner as the normal PIP synthase substrate, leading to the synthesis of a phosphonate analogue of PIP (PI-C-P), which had a structure similar to that of the natural product, PIP. In addition, PI-C-P had high inhibitory activity against PIP synthase.

  6. Human phagocytes lack the ability to kill Mycobacterium gordonae, a non-pathogenic mycobacteria.

    PubMed

    Reyes-Ruvalcaba, David; González-Cortés, Carolina; Rivero-Lezcano, Octavio M

    2008-02-15

    Non-pathogenic mycobacteria, like Mycobacterium gordonae, are rarely associated to disease. The analysis of the mechanisms which are successful against them in the human host may provide useful information to understand why they fail against the pathogenic M. tuberculosis. We have developed an infection model to test the ability of human phagocytes to kill two strains of M. gordonae, HL184G and an attenuated variety, HL184Gat. As controls we included a strain of M. tuberculosis (HL186T) and another one of L. pneumophila (ATCC13151). We observed that human phagocytes lack the intrinsic ability to eliminate either M. gordonae or M. tuberculosis, but they can kill the attenuated strain. We found a relationship between pathogenicity and the pattern of cytokine production. Thus, both the pathogenic M. tuberculosis and Legionella pneumophila, but not the non-pathogenic M. gordonae, induced the production of significantly different levels of IL-1beta, IL-6 and TNF-alpha in monocytes and IL-8 in neutrophils. Although both monocytes and neutrophils killed HL184Gat, but not HL184G, the patterns of cytokine production induced by either strain were identical. Addition of INF-gamma and/or TNF-alpha did not enhance the antimycobacterial activity of phagocytes.

  7. Current methods in the molecular typing of Mycobacterium tuberculosis and other mycobacteria.

    PubMed

    Jagielski, Tomasz; van Ingen, Jakko; Rastogi, Nalin; 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.

  8. Quantitative proteomics reveals novel insights into isoniazid susceptibility in mycobacteria mediated by a universal stress protein.

    PubMed

    Hu, Xinling; Li, Xiaojing; Huang, Lige; Chan, John; Chen, Yuling; Deng, Haiteng; Mi, Kaixia

    2015-03-01

    Tuberculosis (TB) is caused by the ancient pathogen, Mycobacterium tuberculosis, and is one of the most serious infectious diseases in the world. Isoniazid (INH) is an important first-line drug for the treatment of active and latent TB. INH resistance is an increasing problem in the treatment of TB. Phenotypic resistance to INH, however, is poorly understood. In this study, we constructed a strain of Mycobacterium bovis BCG that overexpresses the latency-related universal stress protein (USP), BCG_2013, and designated this strain BCG-2013. BCG_2013 overexpression increased susceptibility to INH compared with that of the wild-type strain, BCG-pMV261. Quantitative proteomic analysis revealed that BCG_2013 overexpression resulted in the upregulation of 50 proteins and the downregulation of 26 proteins among the 1500 proteins identified. Upregulation of catalase-peroxidase KatG expression in BCG-2013 was observed and confirmed by qPCR, whereas expression of other INH resistance-related proteins did not change. In addition, differential expression of the mycobacterial persistence regulator MprA and its regulatory proteins was observed. BCG_2013 and katG mRNA levels increased in a Wayne dormancy model, whereas MprA mRNA levels decreased. Taken together, our results suggest that the increase in KatG levels induced by increased BCG_2013 levels underlies the phenotypic susceptibility of mycobacteria to INH.

  9. Calcaneal Osteomyelitis due to Non-tuberculous Mycobacteria: A Case Report.

    PubMed

    Yi, Tae-Im; Ha, Seung-A; Choe, Yeo-Reum; Kim, Joo-Sup; Kwon, Kye-Won

    2016-02-01

    Osteomyelitis is a bone infection caused by bacteria or other germs. Gram-positive cocci are the most common etiological organisms of calcaneal osteomyelitis; whereas, non-tuberculous mycobacteria (NTM) are rarely documented. We reported a case of NTM calcaneal osteomyelitis in a 51-year-old female patient. She had been previously treated in many local clinics with multiple local steroid injection over 50 times and extracorporeal shock-wave therapy over 20 times with the impression of plantar fasciitis for 3 years prior. Diagnostic workup revealed a calcaneal osteomyelitis and polymerase chain reaction assay on bone aspirate specimens confirmed the diagnosis of non-tuberculous mycobacterial osteomyelitis. The patient had a partial calcanectomy with antitubercular therapy. Six months after surgery, a follow-up magnetic resonance imaging showed localized chronic osteomyelitis with abscess formation. We continued anti-tubercular therapy without operation. At 18-month follow-up after surgery and comprehensive rehabilitation therapy, she was ambulating normally and able to carry out her daily activities without any discomfort. PMID:26949685

  10. Spotlight on mycobacteria and dendritic cells: will novel targets to fight tuberculosis emerge?

    PubMed Central

    Mortellaro, Alessandra; Robinson, Lucy; Ricciardi-Castagnoli, Paola

    2009-01-01

    Over thousands of years microbes and mammals have co-evolved, resulting in extraordinarily sophisticated molecular mechanisms permitting the organisms to survive together. Mycobacterium tuberculosis is one of the best examples of successful co-evolution, since the bacilli have infected one third of the human population, but in 90% of the cases without causing overt disease. Despite this, increasing incidence of Human Immunodeficiency Virus (HIV) infection and the emergence of drug-resistant strains means that tuberculosis is in fact an extremely serious emerging threat to global health. Decades of work have focused on the interaction of this pathogen with its established cellular host, the macrophage, but still novel therapeautics remain elusive. While the macrophage is clearly important, recent evidence suggests that understanding the role of dendritic cells, which are key regulators of immunity, may be a crucial step in identifying new means of controlling this disease. Novel technologies, in particular genome-wide transcriptome analyses, are advancing our ability to dissect the complex dynamic relationships between dendritic cells and mycobacteria, highlighting new areas for study that have not been previously explored. PMID:20049700

  11. Multicenter Study of Prevalence of Nontuberculous Mycobacteria in Patients with Cystic Fibrosis in France ▿

    PubMed Central

    Roux, Anne-Laure; Catherinot, Emilie; Ripoll, Fabienne; Soismier, Nathalie; Macheras, Edouard; Ravilly, Sophie; Bellis, Gil; Vibet, Marie-Anne; Le Roux, Evelyne; Lemonnier, Lydie; Gutierrez, Cristina; Vincent, Véronique; Fauroux, Brigitte; Rottman, Martin; Guillemot, Didier; Gaillard, Jean-Louis

    2009-01-01

    We performed a multicenter prevalence study of nontuberculous mycobacteria (NTM) involving 1,582 patients (mean age, 18.9 years; male/female ratio, 1.06) with cystic fibrosis in France. The overall NTM prevalence (percentage of patients with at least one positive culture) was 6.6% (104/1,582 patients), with prevalences ranging from 3.7% (in the east of France) to 9.6% (in the greater Paris area). Mycobacterium abscessus complex (MABSC; 50 patients) and Mycobacterium avium complex (MAC; 23 patients) species were the most common NTM, and the only ones associated with fulfillment of the American Thoracic Society bacteriological criteria for NTM lung disease. The “new” species, Mycobacterium bolletii and Mycobacterium massiliense, accounted for 40% of MABSC isolates. MABSC species were isolated at all ages, with a prevalence peak between 11 and 15 years of age (5.8%), while MAC species reached their highest prevalence value among patients over 25 years of age (2.2%). PMID:19846643

  12. Mycobacteria Infection in Incomplete Transverse Myelitis Is Refractory to Steroids: A Pilot Study

    PubMed Central

    Feng, Yanqing; Guo, Ning; Liu, Junxiu; Chen, Xi; Sun, Qiaosong; Lai, Rong; Huang, Fan

    2011-01-01

    Incomplete transverse myelitis (ITM) of unknown origin is associated with high rates of morbidity and mortality. This prospective, open-label study was undertaken to determine whether antituberculous treatment (ATT) might help patients with ITM whose condition continues to deteriorate despite receiving IV methylprednisolone treatment. The study consisted of 67 patients with steroid-refractory ITM in whom Mycobacterium tuberculosis (MTB) was suspected clinically and in whom other known causes of myelopathy were excluded. The study occurred from January 2003 to June 2010. Patients underwent trial chemotherapy with ATT. Efficacy was assessed by the American Spinal Injury Association (ASIA) scoring system, the Barthel Index (BI) and the Hauser Ambulation Index (AI) at baseline, 12 months, and 24 months, using magnetic resonance imaging (MRI). Of the 67 patients enrolled, 51 were assessed and 16 withdrew. At 24 months, 49 patients experienced benefits as indicated by significantly increased ASIA and BI scores. The Hauser AI index also improved with markedly decreased abnormal signals in spinal cord MRI over time. The results from this prospective study provide beneficial clinical and MRI data on the efficacy of ATT in ITM patients and suggests mycobacteria may be an important and neglected cause of myelitis. PMID:21331384

  13. Culture-Independent Identification of Nontuberculous Mycobacteria in Cystic Fibrosis Respiratory Samples.

    PubMed

    Caverly, Lindsay J; Carmody, Lisa A; Haig, Sarah-Jane; Kotlarz, Nadine; Kalikin, Linda M; Raskin, Lutgarde; LiPuma, John J

    2016-01-01

    Respiratory tract infections with nontuberculous mycobacteria (NTM) are increasing in prevalence and are a significant cause of lung function decline in individuals with cystic fibrosis (CF). NTM have been detected in culture-independent analyses of CF airway microbiota at lower rates than would be expected based on published prevalence data, likely due to poor lysing of the NTM cell wall during DNA extraction. We compared a standard bacterial lysis protocol with a modified method by measuring NTM DNA extraction by qPCR and NTM detection with bacterial 16S rRNA gene sequencing. The modified method improved NTM DNA recovery from spiked CF sputum samples by a mean of 0.53 log10 copies/mL for M. abscessus complex and by a mean of 0.43 log10 copies/mL for M. avium complex as measured by qPCR targeting the atpE gene. The modified method also improved DNA sequence based NTM detection in NTM culture-positive CF sputum and bronchoalveolar lavage samples; however, both qPCR and 16S rRNA gene sequencing remained less sensitive than culture for NTM detection. We highlight the limitations of culture-independent identification of NTM from CF respiratory samples, and illustrate how alterations in the bacterial lysis and DNA extraction process can be employed to improve NTM detection with both qPCR and 16S rRNA gene sequencing. PMID:27093603

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

    PubMed

    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.

  15. Persistence of Nontuberculous Mycobacteria in a Drinking Water System after Addition of Filtration Treatment

    PubMed Central

    Hilborn, Elizabeth D.; Covert, Terry C.; Yakrus, Mitchell A.; Harris, Stephanie I.; Donnelly, Sandra F.; Rice, Eugene W.; Toney, Sean; Bailey, Stephanie A.; Stelma, Gerard N.

    2006-01-01

    There is evidence that drinking water may be a source of infections with pathogenic nontuberculous mycobacteria (NTM) in humans. One method by which NTM are believed to enter drinking water distribution systems is by their intracellular colonization of protozoa. Our goal was to determine whether we could detect a reduction in the prevalence of NTM recovered from an unfiltered surface drinking water system after the addition of ozonation and filtration treatment and to characterize NTM isolates by using molecular methods. We sampled water from two initially unfiltered surface drinking water treatment plants over a 29-month period. One plant received the addition of filtration and ozonation after 6 months of sampling. Sample sites included those at treatment plant effluents, distributed water, and cold water taps (point-of-use [POU] sites) in public or commercial buildings located within each distribution system. NTM were recovered from 27% of the sites. POU sites yielded the majority of NTM, with >50% recovery despite the addition of ozonation and filtration. Closely related electrophoretic groups of Mycobacterium avium were found to persist at POU sites for up to 26 months. Water collected from POU cold water outlets was persistently colonized with NTM despite the addition of ozonation and filtration to a drinking water system. This suggests that cold water POU outlets need to be considered as a potential source of chronic human exposure to NTM. PMID:16957205

  16. Investigating the effectiveness of St John's wort herb as an antimicrobial agent against mycobacteria.

    PubMed

    Mortensen, Trent; Shen, Shujie; Shen, Fenann; Walsh, Marie K; Sims, Ronald C; Miller, Charles D

    2012-09-01

    A persistent need exists for effective treatment agents for mycobacterial infections. This research investigated the effectiveness of the Hypericum perforatum herb (commonly known as St John's wort; SJW) in its growth inhibition of mycobacteria. A SJW extract was effective at inhibiting five nonpathogenic Mycobacterium isolates and Bacillus subtilis, but not Escherichia coli. Quantitative studies of concentration sensitivity to the SJW extract were performed with minimal bactericidal concentrations (MBC) ranging from 0.33 to 2.66 mg extract/mL. The SJW compounds hyperforin (Hfn), hypericin (Hpn), and pseudohypericin (Phn) were quantified in the extract using HPLC. The SJW extract solution of 133 mg extract/mL used in this study contained 2.3 mg Hfn/mL, 0.8 mg Hpn/mL, and 2.1 mg Phn/mL. Purified Hfn, Hpn, and Phn were tested for inhibitory activity against Mycobacterium JLS (M. JLS) at similar concentrations used in the crude extract. While Hfn was inhibitory at 46 µg/mL, none of the purified SJW constituents were bactericidal at concentrations corresponding to SJW treatments. Scanning electron microscopy (SEM) analysis of SJW-treated M. JLS cells showed changes in cell surface morphology.

  17. Nontuberculous Mycobacteria on Ready-to-Eat, Raw and Frozen Fruits and Vegetables.

    PubMed

    Dziedzinska, Radka; Makovcova, Jitka; Kaevska, Marija; Slany, Michal; Babak, Vladimir; Moravkova, Monika

    2016-08-01

    The consumption of fruits and vegetables is increasing worldwide because of the positive impact of these foods on human health. Ready-to-eat, raw whole, and frozen fruits and vegetables were purchased from markets and examined for the presence of nontuberculous mycobacteria (NTM) using culture, real-time PCR (qPCR), and sequencing. Using qPCR, Mycobacterium sp. at 10(0) to 10(4) ge/g (genome equivalents per gram) was found in almost all of the 178 samples; members of the M. avium complex were found only sporadically. Culture and sequencing revealed the presence of 22 viable NTM isolates in 17 samples. In addition to NTM commonly found in the environment, several rarely described isolates of viable NTM were recovered. The presence of Mycobacterium shigaense, which has been previously isolated only from human patients, was found in lettuce, the first time that this species has been found in an environmental sample. Mycobacterium parmense, Mycobacterium palustre, and Mycobacterium llatzerense, which have been previously isolated from human patients and occasionally from soil and water, were recovered from leafy green vegetables. Strawberries and cut salad mixes contained Mycobacterium algericum, Mycobacterium fallax, and Mycobacterium minnesotense. NTM are primarily nonpathogenic. However, consumption of fruits or vegetables contaminated with NTM could represent a health risk for immunocompromised people, children, and the elderly. PMID:27497136

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

    PubMed Central

    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

  19. Chlorine Disinfection of Atypical Mycobacteria Isolated from a Water Distribution System

    PubMed Central

    Le Dantec, Corinne; Duguet, Jean-Pierre; Montiel, Antoine; Dumoutier, Nadine; Dubrou, Sylvie; Vincent, Véronique

    2002-01-01

    We studied the resistance of various mycobacteria isolated from a water distribution system to chlorine. Chlorine disinfection efficiency is expressed as the coefficient of lethality (liters per minute per milligram) as follows: Mycobacterium fortuitum (0.02) > M. chelonae (0.03) > M. gordonae (0.09) > M. aurum (0.19). For a C · t value (product of the disinfectant concentration and contact time) of 60 mg · min · liter−1, frequently used in water treatment lines, chlorine disinfection inactivates over 4 log units of M. gordonae and 1.5 log units of M. fortuitum or M. chelonae. C · t values determined under similar conditions show that even the most susceptible species, M. aurum and M. gordonae, are 100 and 330 times more resistant to chlorine than Escherichia coli. We also investigated the effects of different parameters (medium, pH, and temperature) on chlorine disinfection in a chlorine-resistant M. gordonae model. Our experimental results follow the Arrhenius equation, allowing the inactivation rate to be predicted at different temperatures. Our results show that M. gordonae is more resistant to chlorine in low-nutrient media, such as those encountered in water, and that an increase in temperature (from 4°C to 25°C) and a decrease in pH result in better inactivation. PMID:11872446

  20. Increased Frequency of Nontuberculous Mycobacteria Detection at Potable Water Taps within the United States.

    PubMed

    Donohue, Maura J; Mistry, Jatin H; Donohue, Joyce M; O'Connell, Katharine; King, Dawn; Byran, Jules; Covert, Terry; Pfaller, Stacy

    2015-05-19

    Nontuberculous mycobacteria (NTMs) are environmental microorganisms that can cause infections in humans, primarily in the lung and soft tissue. The prevalence of NTM-associated diseases is increasing in the United States. Exposure to NTMs occurs primarily through human interactions with water (especially aerosolized). Potable water from sites across the U.S. was collected to investigate the presence of NTM. Water from 68 taps was sampled 4 times over the course of 2 years. In total, 272 water samples were examined for NTM using a membrane filtration, culture method. Identification of NTM isolates was accomplished by polymerase chain reaction (PCR) amplification of the 16S rRNA and hsp65 genes. NTMs were detected in 78% of the water samples. The NTM species detected most frequently were: Mycobacterium mucogenicum (52%), Mycobacterium avium (30%), and Mycobacterium gordonae (25%). Of the taps that were repeatedly positive for NTMs, the species M. avium, M. mucogenicum, and Mycobacterium abscessus were found to persist most frequently. This study also observed statistically significant higher levels of NTM in chloraminated water than in chlorinated water.

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

    PubMed

    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. PMID:24989695

  2. Impact of Protein Domains on PE_PGRS30 Polar Localization in Mycobacteria

    PubMed Central

    Minerva, Mariachiara; Anoosheh, Saber; Palucci, Ivana; Iantomasi, Raffaella; Palmieri, Valentina; Camassa, Serena; Sali, Michela; Sanguinetti, Maurizio; Bitter, Wilbert; Manganelli, Riccardo; De Spirito, Marco; Delogu, Giovanni

    2014-01-01

    PE_PGRS proteins are unique to the Mycobacterium tuberculosis complex and a number of other pathogenic mycobacteria. PE_PGRS30, which is required for the full virulence of M. tuberculosis (Mtb), has three main domains, i.e. an N-terminal PE domain, repetitive PGRS domain and the unique C-terminal domain. To investigate the role of these domains, we expressed a GFP-tagged PE_PGRS30 protein and a series of its functional deletion mutants in different mycobacterial species (Mtb, Mycobacterium bovis BCG and Mycobacterium smegmatis) and analysed protein localization by confocal microscopy. We show that PE_PGRS30 localizes at the mycobacterial cell poles in Mtb and M. bovis BCG but not in M. smegmatis and that the PGRS domain of the protein strongly contributes to protein cellular localization in Mtb. Immunofluorescence studies further showed that the unique C-terminal domain of PE_PGRS30 is not available on the surface, except when the PGRS domain is missing. Immunoblot demonstrated that the PGRS domain is required to maintain the protein strongly associated with the non-soluble cellular fraction. These results suggest that the repetitive GGA-GGN repeats of the PGRS domain contain specific sequences that contribute to protein cellular localization and that polar localization might be a key step in the PE_PGRS30-dependent virulence mechanism. PMID:25390359

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

    PubMed

    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.

  4. The Mannose Receptor Is Involved in the Phagocytosis of Mycobacteria-Induced Apoptotic Cells

    PubMed Central

    2016-01-01

    Upon Mycobacterium tuberculosis infection, macrophages may undergo apoptosis, which has been considered an innate immune response. The pathways underlying the removal of dead cells in homeostatic apoptosis have been extensively studied, but little is known regarding how cells that undergo apoptotic death during mycobacterial infection are removed. This study shows that macrophages induced to undergo apoptosis with mycobacteria cell wall proteins are engulfed by J-774A.1 monocytic cells through the mannose receptor. This demonstration was achieved through assays in which phagocytosis was inhibited with a blocking anti-mannose receptor antibody and with mannose receptor competitor sugars. Moreover, elimination of the mannose receptor by a specific siRNA significantly diminished the expression of the mannose receptor and the phagocytosis of apoptotic cells. As shown by immunofluorescence, engulfed apoptotic bodies are initially located in Rab5-positive phagosomes, which mature to express the phagolysosome marker LAMP1. The phagocytosis of dead cells triggered an anti-inflammatory response with the production of TGF-β and IL-10 but not of the proinflammatory cytokines IL-12 and TNF-α. This study documents the previously unreported participation of the mannose receptor in the removal of apoptotic cells in the setting of tuberculosis (TB) infection. The results challenge the idea that apoptotic cell phagocytosis in TB has an immunogenic effect. PMID:27413759

  5. Nontuberculous Mycobacteria on Ready-to-Eat, Raw and Frozen Fruits and Vegetables.

    PubMed

    Dziedzinska, Radka; Makovcova, Jitka; Kaevska, Marija; Slany, Michal; Babak, Vladimir; Moravkova, Monika

    2016-08-01

    The consumption of fruits and vegetables is increasing worldwide because of the positive impact of these foods on human health. Ready-to-eat, raw whole, and frozen fruits and vegetables were purchased from markets and examined for the presence of nontuberculous mycobacteria (NTM) using culture, real-time PCR (qPCR), and sequencing. Using qPCR, Mycobacterium sp. at 10(0) to 10(4) ge/g (genome equivalents per gram) was found in almost all of the 178 samples; members of the M. avium complex were found only sporadically. Culture and sequencing revealed the presence of 22 viable NTM isolates in 17 samples. In addition to NTM commonly found in the environment, several rarely described isolates of viable NTM were recovered. The presence of Mycobacterium shigaense, which has been previously isolated only from human patients, was found in lettuce, the first time that this species has been found in an environmental sample. Mycobacterium parmense, Mycobacterium palustre, and Mycobacterium llatzerense, which have been previously isolated from human patients and occasionally from soil and water, were recovered from leafy green vegetables. Strawberries and cut salad mixes contained Mycobacterium algericum, Mycobacterium fallax, and Mycobacterium minnesotense. NTM are primarily nonpathogenic. However, consumption of fruits or vegetables contaminated with NTM could represent a health risk for immunocompromised people, children, and the elderly.

  6. Location of acyl groups of trehalose-containing lipooligosaccharides of mycobacteria.

    PubMed Central

    Camphausen, R T; McNeil, M; Jardine, I; Brennan, P J

    1987-01-01

    A variant of a Mycobacterium sp. originating in a patient with Crohn's disease, but not necessarily implicated in the disease, provided a simple version of a newer class of species-specific surface glycolipids, the trehalose-containing lipooligosaccharides. A combination of high-resolution 1H nuclear magnetic resonance, methylation, ethylation, and absolute configurational analysis established the structure of the oligosaccharide unit as beta-D-Glcp(1----3)-alpha-L-Rhap(1----3)-alpha-D-Glcp(1----1)-alph a-D-Glcp (where Glc is glucose, Rha is rhamnose, and p is pyranosyl), and gas chromatography-electron impact mass spectrometry allowed identification of the fatty acyl esters as primarily 2,4-dimethyltetradecanoate. The relative simplicity of the glycolipid combined with the application of a mild methylation procedure and californium-252 plasma desorption mass spectrometry allowed recognition of three such acyl residues on the 3-, 4-, and 6-hydroxyl positions of the terminal glucosyl residue of the trehalose unit. Thus, the glycolipid is decidedly amphipathic yet is clearly not membranous. This observation leads to speculation about the role of these novel lipooligosaccharides in contributing to the outer segment of the hydrophobic barrier of the cell wall of certain mycobacteria. Images PMID:3680168

  7. Multicenter study of prevalence of nontuberculous mycobacteria in patients with cystic fibrosis in france.

    PubMed

    Roux, Anne-Laure; Catherinot, Emilie; Ripoll, Fabienne; Soismier, Nathalie; Macheras, Edouard; Ravilly, Sophie; Bellis, Gil; Vibet, Marie-Anne; Le Roux, Evelyne; Lemonnier, Lydie; Gutierrez, Cristina; Vincent, Véronique; Fauroux, Brigitte; Rottman, Martin; Guillemot, Didier; Gaillard, Jean-Louis

    2009-12-01

    We performed a multicenter prevalence study of nontuberculous mycobacteria (NTM) involving 1,582 patients (mean age, 18.9 years; male/female ratio, 1.06) with cystic fibrosis in France. The overall NTM prevalence (percentage of patients with at least one positive culture) was 6.6% (104/1,582 patients), with prevalences ranging from 3.7% (in the east of France) to 9.6% (in the greater Paris area). Mycobacterium abscessus complex (MABSC; 50 patients) and Mycobacterium avium complex (MAC; 23 patients) species were the most common NTM, and the only ones associated with fulfillment of the American Thoracic Society bacteriological criteria for NTM lung disease. The "new" species, Mycobacterium bolletii and Mycobacterium massiliense, accounted for 40% of MABSC isolates. MABSC species were isolated at all ages, with a prevalence peak between 11 and 15 years of age (5.8%), while MAC species reached their highest prevalence value among patients over 25 years of age (2.2%). PMID:19846643

  8. ATP synthase in mycobacteria: special features and implications for a function as drug target.

    PubMed

    Lu, Ping; Lill, Holger; Bald, Dirk

    2014-07-01

    ATP synthase is a ubiquitous enzyme that is largely conserved across the kingdoms of life. This conservation is in accordance with its central role in chemiosmotic energy conversion, a pathway utilized by far by most living cells. On the other hand, in particular pathogenic bacteria whilst employing ATP synthase have to deal with energetically unfavorable conditions such as low oxygen tensions in the human host, e.g. Mycobacterium tuberculosis can survive in human macrophages for an extended time. It is well conceivable that such ATP synthases may carry idiosyncratic features that contribute to efficient ATP production. In this review genetic and biochemical data on mycobacterial ATP synthase are discussed in terms of rotary catalysis, stator composition, and regulation of activity. ATP synthase in mycobacteria is of particular interest as this enzyme has been validated as a target for promising new antibacterial drugs. A deeper understanding of the working of mycobacterial ATP synthase and its atypical features can provide insight in adaptations of bacterial energy metabolism. Moreover, pinpointing and understanding critical differences as compared with human ATP synthase may provide input for the design and development of selective ATP synthase inhibitors as antibacterials. This article is part of a Special Issue entitled: 18th European Bioenergetic Conference.

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

    PubMed Central

    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

  10. Fragment-Based Whole Cell Screen Delivers Hits against M. tuberculosis and Non-tuberculous Mycobacteria

    PubMed Central

    Moreira, Wilfried; Lim, Jia Jie; Yeo, Si Ying; Ramanujulu, Pondy M.; Dymock, Brian W.; Dick, Thomas

    2016-01-01

    Reactive multi-target ‘fragment drugs’ represent critical components of current tuberculosis regimens. These compounds, such as pyrazinamide, are old synthetic antimycobacterials that are activated inside Mycobacterium tuberculosis bacilli and are smaller than the usual drug-like, single-target molecules. Based on the success of small ‘dirty’ drugs in the chemotherapy of tuberculosis, we suggested previously that fragment-based whole cell screens should be introduced in our current antimycobacterial drug discovery efforts. Here, we carried out such a screen and characterized bactericidal activity, selectivity and spectrum of hits we obtained. A library of 1725 fragments was tested at a single concentration for growth inhibitory activity against M. bovis BCG as screening strain and 38 of 116 primary hits were confirmed in dose response analyses to be active against virulent M. tuberculosis. Bacterial kill experiments showed that most hits displayed bactericidal activity at their minimal inhibitory concentration. Cytotoxicity assays established that a large proportion of hits displayed a favorable selectivity index for mammalian cells. Importantly, one third of M. tuberculosis active fragments were also active against M. abscessus and M. avium, two emerging non-tuberculous mycobacterial (NTM) pathogens, opening the opportunity to develop broad spectrum antimycobacterials. Activity determination against Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa) bacteria, as well as fungi (Candida albicans, Cryptococcus neoformans) showed only a small overlap indicating a generally narrow spectrum of these novel antimicrobial hits for mycobacteria. In conclusion, we carried out the first fragment-based whole cell screen against bacteria and identified a substantial number of hits with excellent physicochemical properties and dual activity against M. tuberculosis and NTM

  11. Fragment-Based Whole Cell Screen Delivers Hits against M. tuberculosis and Non-tuberculous Mycobacteria.

    PubMed

    Moreira, Wilfried; Lim, Jia Jie; Yeo, Si Ying; Ramanujulu, Pondy M; Dymock, Brian W; Dick, Thomas

    2016-01-01

    Reactive multi-target 'fragment drugs' represent critical components of current tuberculosis regimens. These compounds, such as pyrazinamide, are old synthetic antimycobacterials that are activated inside Mycobacterium tuberculosis bacilli and are smaller than the usual drug-like, single-target molecules. Based on the success of small 'dirty' drugs in the chemotherapy of tuberculosis, we suggested previously that fragment-based whole cell screens should be introduced in our current antimycobacterial drug discovery efforts. Here, we carried out such a screen and characterized bactericidal activity, selectivity and spectrum of hits we obtained. A library of 1725 fragments was tested at a single concentration for growth inhibitory activity against M. bovis BCG as screening strain and 38 of 116 primary hits were confirmed in dose response analyses to be active against virulent M. tuberculosis. Bacterial kill experiments showed that most hits displayed bactericidal activity at their minimal inhibitory concentration. Cytotoxicity assays established that a large proportion of hits displayed a favorable selectivity index for mammalian cells. Importantly, one third of M. tuberculosis active fragments were also active against M. abscessus and M. avium, two emerging non-tuberculous mycobacterial (NTM) pathogens, opening the opportunity to develop broad spectrum antimycobacterials. Activity determination against Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa) bacteria, as well as fungi (Candida albicans, Cryptococcus neoformans) showed only a small overlap indicating a generally narrow spectrum of these novel antimicrobial hits for mycobacteria. In conclusion, we carried out the first fragment-based whole cell screen against bacteria and identified a substantial number of hits with excellent physicochemical properties and dual activity against M. tuberculosis and NTM pathogens

  12. Non-tuberculous mycobacteria in children: muddying the waters of tuberculosis diagnosis.

    PubMed

    López-Varela, Elisa; García-Basteiro, Alberto L; Santiago, Begoña; Wagner, Dirk; van Ingen, Jakko; Kampmann, Beate

    2015-03-01

    Non-tuberculous mycobacteria (NTM) are a large family of acid-fast bacteria, widespread in the environment. In children, NTM cause lymphadenitis, skin and soft tissue infections, and occasionally also lung disease and disseminated infections. These manifestations can be indistinguishable from tuberculosis on the basis of clinical and radiological findings and tuberculin skin testing. A diagnostic and therapeutic problem for respiratory physicians and other clinicians is therefore evident, particularly in settings where childhood tuberculosis is common, and bacteriological confirmation of any mycobacterial disease is difficult because of low availability of laboratory services in low-resource settings and the inherent paucibacillary nature of mycobacterial disease in childhood. The epidemiology of NTM varies by world region, and attempts to understand the burden of NTM disease and to identify risk factors in the paediatric population are hampered by inadequate mandatory NTM reporting and the overlap of clinical presentation with tuberculosis. The immune response to both NTM and Mycobacterium tuberculosis is based on cellular immunity and relies on the type-1 cytokine pathway. The disruption of this immune response by genetic or acquired mechanisms, such as mendelian susceptibility to mycobacterial disease or HIV, might result in predisposition to mycobacterial infections. Published diagnostic and management guidelines do not provide specific advice for diagnosis of NTM in children, from whom the quantity and quality of diagnostic samples are often suboptimum. Treatment of NTM infections is very different from the treatment of tuberculosis, depends on the strain and anatomical site of infection, and often involves antibiotic combinations, surgery, or both. In this Review, we summarise the epidemiological and clinical features of NTM infection in children, with a specific focus on the implications for public health in settings with a high endemic burden of childhood

  13. Fragment-Based Whole Cell Screen Delivers Hits against M. tuberculosis and Non-tuberculous Mycobacteria

    PubMed Central

    Moreira, Wilfried; Lim, Jia Jie; Yeo, Si Ying; Ramanujulu, Pondy M.; Dymock, Brian W.; Dick, Thomas

    2016-01-01

    Reactive multi-target ‘fragment drugs’ represent critical components of current tuberculosis regimens. These compounds, such as pyrazinamide, are old synthetic antimycobacterials that are activated inside Mycobacterium tuberculosis bacilli and are smaller than the usual drug-like, single-target molecules. Based on the success of small ‘dirty’ drugs in the chemotherapy of tuberculosis, we suggested previously that fragment-based whole cell screens should be introduced in our current antimycobacterial drug discovery efforts. Here, we carried out such a screen and characterized bactericidal activity, selectivity and spectrum of hits we obtained. A library of 1725 fragments was tested at a single concentration for growth inhibitory activity against M. bovis BCG as screening strain and 38 of 116 primary hits were confirmed in dose response analyses to be active against virulent M. tuberculosis. Bacterial kill experiments showed that most hits displayed bactericidal activity at their minimal inhibitory concentration. Cytotoxicity assays established that a large proportion of hits displayed a favorable selectivity index for mammalian cells. Importantly, one third of M. tuberculosis active fragments were also active against M. abscessus and M. avium, two emerging non-tuberculous mycobacterial (NTM) pathogens, opening the opportunity to develop broad spectrum antimycobacterials. Activity determination against Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa) bacteria, as well as fungi (Candida albicans, Cryptococcus neoformans) showed only a small overlap indicating a generally narrow spectrum of these novel antimicrobial hits for mycobacteria. In conclusion, we carried out the first fragment-based whole cell screen against bacteria and identified a substantial number of hits with excellent physicochemical properties and dual activity against M. tuberculosis and NTM

  14. Distributive Conjugal Transfer: New Insights into Horizontal Gene Transfer and Genetic Exchange in Mycobacteria

    PubMed Central

    Derbyshire, Keith M.; Gray, Todd A.

    2014-01-01

    The last decade has seen an explosion in the application of genomic tools across all biological disciplines. This is also true for mycobacteria, where whole genome sequences are now available for pathogens and non-pathogens alike. Genomes within the Mycobacterium tuberculosis Complex (MTBC) bear the hallmarks of horizontal gene transfer (HGT). Conjugation is the form of HGT with the highest potential capacity and evolutionary influence. Donor and recipient strains of Mycobacterium smegmatis actively conjugate upon co-culturing in biofilms and on solid media. Whole genome sequencing of the transconjugant progeny demonstrated the incredible scale and range of genomic variation that conjugation generates. Transconjugant genomes are complex mosaics of the parental strains. Some transconjugant genomes are up to one-quarter donor-derived, distributed over 30 segments. Transferred segments range from ~50 bp to ~225,000 bp in length, and are exchanged with their recipient orthologs all around the genome. This unpredictable genome-wide infusion of DNA sequences is called Distributive Conjugal Transfer (DCT), to distinguish it from traditional oriT-based conjugation. The mosaicism generated in a single transfer event resembles that seen from meiotic recombination in sexually reproducing organisms, and contrasts with traditional models of HGT. This similarity allowed the application of a GWAS-like approach to map the donor genes that confer a donor mating identity phenotype. The mating identity genes map to the esx1 locus, expanding the central role of ESX-1 function in conjugation. The potential for DCT to instantaneously blend genomes will affect how we view mycobacterial evolution, and provide new tools for the facile manipulation of mycobacterial genomes. PMID:25505644

  15. Critical roles for lipomannan and lipoarabinomannan in cell wall integrity of mycobacteria and pathogenesis of tuberculosis.

    PubMed

    Fukuda, Takeshi; Matsumura, Takayuki; Ato, Manabu; Hamasaki, Maho; Nishiuchi, Yukiko; Murakami, Yoshiko; Maeda, Yusuke; Yoshimori, Tamotsu; Matsumoto, Sohkichi; Kobayashi, Kazuo; Kinoshita, Taroh; Morita, Yasu S

    2013-02-19

    Lipomannan (LM) and lipoarabinomannan (LAM) are mycobacterial glycolipids containing a long mannose polymer. While they are implicated in immune modulations, the significance of LM and LAM as structural components of the mycobacterial cell wall remains unknown. We have previously reported that a branch-forming mannosyltransferase plays a critical role in controlling the sizes of LM and LAM and that deletion or overexpression of this enzyme results in gross changes in LM/LAM structures. Here, we show that such changes in LM/LAM structures have a significant impact on the cell wall integrity of mycobacteria. In Mycobacterium smegmatis, structural defects in LM and LAM resulted in loss of acid-fast staining, increased sensitivity to β-lactam antibiotics, and faster killing by THP-1 macrophages. Furthermore, equivalent Mycobacterium tuberculosis mutants became more sensitive to β-lactams, and one mutant showed attenuated virulence in mice. Our results revealed previously unknown structural roles for LM and LAM and further demonstrated that they are important for the pathogenesis of tuberculosis. IMPORTANCE Tuberculosis (TB) is a global burden, affecting millions of people worldwide. Mycobacterium tuberculosis is a causative agent of TB, and understanding the biology of M. tuberculosis is essential for tackling this devastating disease. The cell wall of M. tuberculosis is highly impermeable and plays a protective role in establishing infection. Among the cell wall components, LM and LAM are major glycolipids found in all Mycobacterium species, show various immunomodulatory activities, and have been thought to play roles in TB pathogenesis. However, the roles of LM and LAM as integral parts of the cell wall structure have not been elucidated. Here we show that LM and LAM play critical roles in the integrity of mycobacterial cell wall and the pathogenesis of TB. These findings will now allow us to seek the possibility that the LM/LAM biosynthetic pathway is a

  16. Nontuberculous Mycobacteria, Fungi, and Opportunistic Pathogens in Unchlorinated Drinking Water in the Netherlands

    PubMed Central

    van der Kooij, Dick

    2013-01-01

    The multiplication of opportunistic pathogens in drinking water supplies might pose a threat to public health. In this study, distributed unchlorinated drinking water from eight treatment plants in the Netherlands was sampled and analyzed for fungi, nontuberculous mycobacteria (NTM), and several opportunistic pathogens by using selective quantitative PCR methods. Fungi and NTM were detected in all drinking water samples, whereas Legionella pneumophila, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Aspergillus fumigatus were sporadically observed. Mycobacterium avium complex and Acanthamoeba spp. were not detected. Season had no influence on the occurrence of these organisms, except for NTM and S. maltophilia, which were present in higher numbers in the summer. Opportunistic pathogens were more often observed in premise plumbing water samples than in samples from the distribution system. The lowest number of these organisms was observed in the finished water at the plant. Thus, fungi, NTM, and some of the studied opportunistic pathogens can multiply in the distribution and premise plumbing systems. Assimilable organic carbon (AOC) and/or total organic carbon (TOC) had no clear effects on fungal and NTM numbers or on P. aeruginosa- and S. maltophilia-positive samples. However, L. pneumophila was detected more often in water with AOC concentrations above 10 μg C liter−1 than in water with AOC levels below 5 μg C liter−1. Finally, samples that contained L. pneumophila, P. aeruginosa, or S. maltophilia were more frequently positive for a second opportunistic pathogen, which shows that certain drinking water types and/or sampling locations promote the growth of multiple opportunistic pathogens. PMID:23160134

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

    PubMed Central

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

    2013-01-01

    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 E. 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 nonhomologous end-joining (NHEJ) catalyzed 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. PMID:21219454

  18. Molecular Identification of Nontuberculous Mycobacteria in Humans in Zimbabwe Using 16S Ribosequencing

    PubMed Central

    Chin’ombe, Nyasha; Muzividzi, Boniface; Munemo, Ellen; Nziramasanga, Pasipanodya

    2016-01-01

    Background: Several nontuberculous mycobacteria (NTM) were previously isolated from diverse environments such as water, soil, sewage, food and animals. Some of these NTM are now known to be opportunistic pathogens of humans. Objective: The main purpose of the study was to identify NTM isolates stored at the National Microbiology Reference Laboratory (NMRL) and were previously isolated from humans during a national tuberculosis (TB) survey. Methods: Pure NTM cultures already isolated from human sputum samples during the national TB survey were retrieved from the NMRL and used for this study. DNA was extracted from the samples and 16S ribosomal RNA gene amplified by polymerase chain reaction. The amplicons were sequenced and bioinformatics tools were used to identify the NTM species. Results: Out of total of 963 NTM isolates stored at the NMRL, 81 were retrieved for speciation. Forty isolates (49.4%) were found to belong to Mycobacterium avium-intracellulare complex (MAC) species. The other 41 isolates (50.6%) were identified as M. lentiflavum (6.2%), M. terrae complex (4.9%), M. paraense (4.9%), M. kansasii (3.7%), M. moriokaense (3.7%), M. asiaticum (2.5%), M. novocastrense (2.5%), M. brasiliensis (2.5%), M. elephantis (2.5%), M. paraffinicum (1.2%), M. bohemicum (1.2%), M. manitobense (1.2%), M. intermedium (1.2%), M. tuberculosis complex (1.2%), M. parakoreense (1.2%), M. florentinum (1.2%), M. litorale (1.2%), M. fluoranthenivorans (1.2%), M. sherrisii (1.2%), M. fortuitum (1.2%) and M septicum (1.2%). Two isolates (2.5%) could not be identified, but were closely related to M. montefiorense and M. phlei respectively. Interestingly, the MAC species were the commonest NTM during the survey. Conclusion: The study emphasizes the importance of identifying species of NTM in Zimbabwe. Future studies need to ascertain their true diversity and clinical relevance. PMID:27335623

  19. Nontuberculous mycobacteria, fungi, and opportunistic pathogens in unchlorinated drinking water in The Netherlands.

    PubMed

    van der Wielen, Paul W J J; van der Kooij, Dick

    2013-02-01

    The multiplication of opportunistic pathogens in drinking water supplies might pose a threat to public health. In this study, distributed unchlorinated drinking water from eight treatment plants in the Netherlands was sampled and analyzed for fungi, nontuberculous mycobacteria (NTM), and several opportunistic pathogens by using selective quantitative PCR methods. Fungi and NTM were detected in all drinking water samples, whereas Legionella pneumophila, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Aspergillus fumigatus were sporadically observed. Mycobacterium avium complex and Acanthamoeba spp. were not detected. Season had no influence on the occurrence of these organisms, except for NTM and S. maltophilia, which were present in higher numbers in the summer. Opportunistic pathogens were more often observed in premise plumbing water samples than in samples from the distribution system. The lowest number of these organisms was observed in the finished water at the plant. Thus, fungi, NTM, and some of the studied opportunistic pathogens can multiply in the distribution and premise plumbing systems. Assimilable organic carbon (AOC) and/or total organic carbon (TOC) had no clear effects on fungal and NTM numbers or on P. aeruginosa- and S. maltophilia-positive samples. However, L. pneumophila was detected more often in water with AOC concentrations above 10 μg C liter(-1) than in water with AOC levels below 5 μg C liter(-1). Finally, samples that contained L. pneumophila, P. aeruginosa, or S. maltophilia were more frequently positive for a second opportunistic pathogen, which shows that certain drinking water types and/or sampling locations promote the growth of multiple opportunistic pathogens.

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

    PubMed Central

    Price, Dominique N.; Kusewitt, Donna F.; Lino, Christopher A.; McBride, Amber A.; Muttil, Pavan

    2016-01-01

    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. PMID:27153120

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

    PubMed

    Price, Dominique N; Kusewitt, Donna F; Lino, Christopher A; McBride, Amber A; Muttil, Pavan

    2016-05-01

    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.

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

    PubMed

    Price, Dominique N; Kusewitt, Donna F; Lino, Christopher A; McBride, Amber A; Muttil, Pavan

    2016-05-01

    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. PMID:27153120

  3. Evaluation of the Speed-oligo Direct Mycobacterium tuberculosis Assay for Molecular Detection of Mycobacteria in Clinical Respiratory Specimens

    PubMed Central

    Lara-Oya, Ana; Mendoza-Lopez, Pablo; Rodriguez-Granger, Javier; Fernández-Sánchez, Ana María; Bermúdez-Ruiz, María Pilar; Toro-Peinado, Inmaculada; Palop-Borrás, Begoña; Navarro-Marí, Jose María

    2013-01-01

    We present the first evaluation of a novel molecular assay, the Speed-oligo Direct Mycobacterium tuberculosis (SO-DMT) assay, which is based on PCR combined with a dipstick for the detection of mycobacteria and the specific identification of M. tuberculosis complex (MTC) in respiratory specimens. A blind evaluation was carried out in two stages: first, under experimental conditions on convenience samples comprising 20 negative specimens, 44 smear- and culture-positive respiratory specimens, and 11 sputa inoculated with various mycobacterium-related organisms; and second, in the routine workflow of 566 fresh respiratory specimens (4.9% acid-fast bacillus [AFB] smear positives, 7.6% MTC positives, and 1.8% nontuberculous mycobacteria [NTM] culture positives) from two Mycobacterium laboratories. SO-DMT assay showed no reactivity in any of the mycobacterium-free specimens or in those with mycobacterium-related organisms. Compared to culture, the sensitivity in the selected smear-positive specimens was 0.91 (0.92 for MTC and 0.90 for NTM), and there was no molecular detection of NTM in a tuberculosis case or vice versa. With respect to culture and clinical data, the sensitivity, specificity, and positive and negative predictive values for the SO-DMT system in routine specimens were 0.76 (0.93 in smear positives [1.0 for MTC and 0.5 for NTM] and 0.56 in smear negatives [0.68 for MTC and 0.16 for NTM]), 0.99, 0.85 (1.00 in smear positives and 0.68 in smear negatives), and 0.97, respectively. Molecular misidentification of NTM cases occurred when testing 2 gastric aspirates from two children with clinically but not microbiologically confirmed lung tuberculosis. The SO-DMT assay appears to be a fast and easy alternative for detecting mycobacteria and differentiating MTC from NTM in smear-positive respiratory specimens. PMID:23100355

  4. Chronic suppurative otitis media due to nontuberculous mycobacteria: A case of successful treatment with topical boric acid.

    PubMed

    Lefebvre, Marie-Astrid; Quach, Caroline; Daniel, Sam J

    2015-07-01

    Nontuberculous mycobacteria (NTM) are an increasingly recognized cause of chronic suppurative otitis media in children with tympanostomy tubes. Treatment of this condition is difficult and typically requires a combination of systemic antibiotics and surgical debridement. We present the first case of a 2-year-old male with chronic suppurative otitis media due to NTM who failed systemic antibiotic therapy and was successfully managed with topical boric acid powder. This report highlights the challenges involved in treating this infection, and introduces boric acid as a potentially valuable component of therapy.

  5. Prediction of Certain Well-Characterized Domains of Known Functions within the PE and PPE Proteins of Mycobacteria.

    PubMed

    Sultana, Rafiya; Tanneeru, Karunakar; Kumar, Ashwin B R; Guruprasad, Lalitha

    2016-01-01

    The PE and PPE protein family are unique to mycobacteria. Though the complete genome sequences for over 500 M. tuberculosis strains and mycobacterial species are available, few PE and PPE proteins have been structurally and functionally characterized. We have therefore used bioinformatics tools to characterize the structure and function of these proteins. We selected representative members of the PE and PPE protein family by phylogeny analysis and using structure-based sequence annotation identified ten well-characterized protein domains of known function. Some of these domains were observed to be common to all mycobacterial species and some were species specific.

  6. Prediction of Certain Well-Characterized Domains of Known Functions within the PE and PPE Proteins of Mycobacteria

    PubMed Central

    Sultana, Rafiya; Tanneeru, Karunakar; Kumar, Ashwin B. R.; Guruprasad, Lalitha

    2016-01-01

    The PE and PPE protein family are unique to mycobacteria. Though the complete genome sequences for over 500 M. tuberculosis strains and mycobacterial species are available, few PE and PPE proteins have been structurally and functionally characterized. We have therefore used bioinformatics tools to characterize the structure and function of these proteins. We selected representative members of the PE and PPE protein family by phylogeny analysis and using structure-based sequence annotation identified ten well-characterized protein domains of known function. Some of these domains were observed to be common to all mycobacterial species and some were species specific. PMID:26891364

  7. Identification of contaminants during primary isolation of mycobacteria in the BACTEC system with the antimicrobial supplement PACT.

    PubMed

    Salfinger, M; Kafader, F M; Hardegger, U; Wüst, J

    1988-04-01

    1500 sputum specimens and bronchial washings were cultured for mycobacteria. One half of the specimen was treated with N-acetyl-L-cysteine--sodium hydroxide (3%) (NALC) and the other with sodium dodecyl (lauryl) sulfate--sodium hydroxide (1%) (SDS). The different species of contaminants found with each pretreatment method with the BACTEC radiometric system were identified. Contamination occurred in 6% by using SDS and in 10% by using NALC. The SDS method was more effective against Bacillus ssp. and Streptomyces ssp., the major contaminants. However, the growth of Pseudomonas ssp. was a problem in both methods. PMID:3394450

  8. Growing Your Own versus Mentoring

    ERIC Educational Resources Information Center

    Gibbs, Greg K.

    2005-01-01

    With the current scarcity of qualified administrative candidates, the author hears many districts talking of "growing their own" administrators. The current practice of "growing your own" appears to be largely driven by specific district needs and finding someone who can best fill those needs in a timely fashion. Minor grooming and limited…

  9. [Detection of pathogenic mycobacteria in the environment of the medical units and of the slaughter-house of an African town (author's transl)].

    PubMed

    Nguematcha, R; Le Noc, P

    1978-01-01

    The authors have made investigations about the presence of pathogen mycobacteria in puddles of rain water and in rill waters of sanitary formations and municipal slaughter-house of Yaoundé. 19 strains of pathogen mycobacteria have been isolated from 84 water samples : 15 M. tuberculosis strains, especially present in the environment of sanitary formations, 4 M. bovis strains, especially present in the environment of the slaughterhouse. The third part of isolated M. tuberculosis strains belongs to the africanum variety of this species, although this variety is prevalent in the human pathologic products. 13 from 19 strains are I.N.H. susceptible.

  10. Performance of the Ogawa-Kudoh method for isolation of mycobacteria in a laboratory with large-scale workload.

    PubMed

    Rivas, C; Coitinho, C; Dafond, V; Corbo, M; Baldjian, M

    2010-01-01

    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. PMID:20589326

  11. Discrimination of intact mycobacteria at the strain level: a combined MALDI-TOF MS and biostatistical analysis.

    PubMed

    Hettick, Justin M; Kashon, Michael L; Slaven, James E; Ma, Yan; Simpson, Janet P; Siegel, Paul D; Mazurek, Gerald N; Weissman, David N

    2006-12-01

    New methodologies for surveillance and identification of Mycobacterium tuberculosis are required to stem the spread of disease worldwide. In addition, the ability to discriminate mycobacteria at the strain level may be important to contact or source case investigations. To this end, we are developing MALDI-TOF MS methods for the identification of M. tuberculosis in culture. In this report, we describe the application of MALDI-TOF MS, as well as statistical analysis including linear discriminant and random forest analysis, to 16 medically relevant strains from four species of mycobacteria, M. tuberculosis, M. avium, M. intracellulare, and M. kansasii. Although species discrimination can be accomplished on the basis of unique m/z values observed in the MS fingerprint spectrum, discrimination at the strain level is predicted on the relative abundance of shared m/z values among strains within a species. For the 16 mycobacterial strains investigated in the present study, it is possible to unambiguously identify strains within a species on the basis of MALDI-TOF MS data. The error rate for classification of individual strains using linear discriminant analysis was 0.053 using 37 m/z variables, whereas the error rate for classification of individual strains using random forest analysis was 0.023 using only 18 m/z variables. In addition, using random forest analysis of MALDI-TOF MS data, it was possible to correctly classify bacterial strains as either M. tuberculosis or non-tuberculous with 100% accuracy.

  12. Dynamics of the phagocytic cell response within the lungs of parabiotic mice infected with mycobacteria with decreasing virulence for mice

    SciTech Connect

    Collins, F.M. )

    1990-07-01

    Alveolar macrophages constitute the first line of defense against an aerogenic mycobacterial challenge. The kinetics of the alveolar macrophage response to an infectious stimulus was studied in parabiotic C57BL/6 x DBA/2 (B6D2)F1 hybrid mice pulse-labeled with tritiated thymidine given to one (donor) animal while the other (recipient) received an equivalent amount of cold thymidine. Lavage fluid collected from uninfected recipients yielded few labeled monocytes. However, after introduction of 10(5) viable Mycobacterium bovis BCG into the lung, an immediate influx of heavily labeled mononuclear cells was observed, peaking around day 3. This cellular response was compared with that induced by several members of the Mycobacterium avium complex of different virulence to mice. The strains M. avium 724 and M. intracellulare 1405, virulent to mice, induced moderate mononuclear cell responses, whereas the avirulent M. intracellulare 1411 induced a predominantly polymorphonuclear rather than mononuclear cell influx, analogous to that seen when heat-killed mycobacteria were introduced into the lung. These results suggest that the mycobacteria within the lung must remain in a metabolically active state in order to induce the maximum mononuclear cell response of the type associated with acquired antituberculous immunity.

  13. Protein kinase C-δ inhibitor, Rottlerin inhibits growth and survival of mycobacteria exclusively through Shikimate kinase.

    PubMed

    Pandey, Sapna; Chatterjee, Aditi; Jaiswal, Swati; Kumar, Sanjay; Ramachandran, Ravishankar; Srivastava, Kishore K

    2016-09-16

    The molecular bases of disease provide exceptional prospect to translate research findings into new drugs. Nevertheless, to develop new and novel chemical entities takes huge amount of time and efforts, mainly due to the stringent processes. Therefore, drug repurposing is one of such strategies which is being used in recent times to identify new pharmacophores. The essential first step in discovery of the specific inhibitor with low toxicity is the identification and elucidation of pathways exclusive to target pathogen. One such target is the shikimate pathway, which is essential for algae, higher plants, bacteria and fungi. Since, this enzyme system is absent in higher eukaryotes and in mammals, the enzymes involved in the pathway provide an attractive target for the development of potentially selective and non toxic antimicrobial agents. Since, so far there is no specific inhibitor which is able to restrain mycobacterial shikimate pathway; we expanded the use of a known kinase inhibitor; Rottlerin, in order to predict the prototype in discovering the specific molecules against this enzyme. For the first time we have shown that Rottlerin inhibits extracellular mycobacteria by affecting Shikimate Kinase (SK) and this effect is further enhanced during the intracellular infection due to the added effect of PKC- δ down-regulation. The molecular docking of Rottlerin with both the mycobacterial SKs, corroborated the inhibition data, and revealed that the effects of SK, in slow and in fast grower mycobacteria are due to the changes in affinity of binding with the drug. PMID:27498028

  14. MmpL transporter-mediated export of cell-wall associated lipids and siderophores in mycobacteria.

    PubMed

    Chalut, Christian

    2016-09-01

    Mycobacteria produce a large variety of surface-exposed lipids with unusual structures. Some of these compounds are ubiquitously present in mycobacteria and play an important role in the structural organization of the cell envelope, while others are species-specific. The biosynthesis of most of these lipids requires modular polyketide synthases (PKS) or non-ribosomal peptide synthetases (NRPS) that are intracellular, suggesting that the assembly of these compounds takes place in the cytosolic compartment or near the inner leaflet of the plasma membrane. The molecular mechanisms that mediate the export of these lipid components across the cell envelope remain poorly understood. Mycobacterial membrane protein Large (MmpL) transporters, a subclass of Resistance-Nodulation-Cell Division (RND) transporters, appear to play a major role in this process, acting as scaffold proteins that couple lipid synthesis and transport. Recent studies have shown that this family of transporters also contributes to siderophore secretion in Mycobacterium tuberculosis. The goal of this review is to provide the most recent advances in our understanding of the molecular mechanisms involved in lipid and siderophore transport mediated by MmpL transporters. PMID:27553408

  15. Birth of space plant growing

    NASA Technical Reports Server (NTRS)

    Mashinskiy, A.; Nechitaylo, G.

    1983-01-01

    The attempts, and successes, to grow plants in space, and get them to fully develop, bloom and produce seeds using orchids are presented. The psychological advantages of the presence of plants onboard space vehicles and space stations is indicated.

  16. Langmuir circulations beneath growing waves

    NASA Astrophysics Data System (ADS)

    Phillips, W. R. C.

    2000-11-01

    The instability of a weakly sheared density stratified two dimensional wavy flow to longitudinal vortices is considered. The instability mechanism is Craik-Leibovich type 2, or CL2, and the problem is posited in the context of Langmuir circulations beneath irrotational wind driven surface waves. Of interest is the influence to the instability of growing or decaying waves according to linear theory. The basis for the study is an initial value problem posed by Leibovich & Paolucci (1981) in which the liquid substrate is of semi-infinite extent and the wind driven current is permitted to grow. At zero Richardson number, relative to the solution for neutral waves, it is found that growing waves act to stabilize the instability while decaying waves are destablizing. Furthemore while growing waves act to increase the spanwise wavenumber at onset, decaying waves act to decrease it. The influence of Prandtl and Richardson numbers is also discussed.

  17. Sociology: The growing climate divide

    NASA Astrophysics Data System (ADS)

    Hoffman, Andrew J.

    2011-07-01

    Climate change has reached the level of a 'scientific consensus', but is not yet a 'social consensus'. New analysis highlights that a growing divide between liberals and conservatives in the American public is a major obstacle to achieving this end.

  18. Method for growing plants aeroponically.

    PubMed

    Zobel, R W; Del Tredici, P; Torrey, J G

    1976-03-01

    A simple, inexpensive system for growing plants with their roots bathed in nutrient mist is described. The aeroponics system uses a spinner from a home humidifier to propel nutrient solution into a polyethylene-lined plywood box atop which plants are supported on plastic light-fixture "egg crating." Success in growing a number of herbaceous and woody species, including nodulated legumes and nonlegumes, is reported. PMID:16659479

  19. Occurrence of Opportunistic Pathogens Legionella Pneumophilaand Non-tuberculous Mycobacteria in Hospital Plumbing Systems

    EPA Science Inventory

    Opportunistic premise plumbing pathogens (OPPPs) such as Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa are frequently detected in the plumbing systems of large buildings. The ability of these organisms to form biofilms and to grow in phagocytic amoeba ar...

  20. Growing self-organizing trees for autonomous hierarchical clustering.

    PubMed

    Doan, Nhat-Quang; Azzag, Hanane; Lebbah, Mustapha

    2013-05-01

    This paper presents a new unsupervised learning method based on growing processes and autonomous self-assembly rules. This method, called Growing Self-organizing Trees (GSoT), can grow both network size and tree topology to represent the topological and hierarchical dataset organization, allowing a rapid and interactive visualization. Tree construction rules draw inspiration from elusive properties of biological organization to build hierarchical structures. Experiments conducted on real datasets demonstrate good GSoT performance and provide visual results that are generated during the training process. PMID:23041056

  1. Usefulness of three-channel multiplex real-time PCR and melting curve analysis for simultaneous detection and identification of the Mycobacterium tuberculosis complex and nontuberculous mycobacteria.

    PubMed

    Hong, Yun Ji; Chung, Young Hoon; Kim, Taek Soo; Song, Sang Hoon; Park, Kyoung Un; Yim, Jae Joon; Song, Junghan; Lee, Jae Ho; Kim, Eui Chong

    2011-11-01

    We attempted to determine the benefits of three-channel multiplex real-time PCR and melting curve analysis not only in detecting and distinguishing between nontuberculous mycobacteria (NTM) and the Mycobacterium tuberculosis complex but also in identifying NTM to the species level.

  2. [A new method for the disruption of cell walls of gram-positive bacteria and mycobacteria on the point of nucleic acid extraction: sand method].

    PubMed

    Şahin, Fikret; Kıyan, Mehmet; Karasartova, Djursun; Çalgın, M Kerem; Akhter, Shameem; Türegün Atasoy, Buse

    2016-01-01

    Nowadays molecular methods are widely used in the rapid diagnosis of infectious agents. Polymerase chain reaction (PCR) is the most preferred method for this purpose. Obtaining sufficient and pure DNA or RNA is important for the PCR. Different DNA extraction protocols such as phenol-chloroform, proteinase K, glass beads and boiling have been used successfully for DNA isolation from gram-negative bacteria. However since gram-positive bacteria have a thicker layer of peptidoglycan and mycobacteria have complex glycolipids in their cell walls, for the isolation of DNA or RNA from these microorganisms, the complex cell wall structure must be eliminated. For this purpose, the bacterial cell wall must be completely or partially removed forming sferoblast using lysostaphin in the Staphylococcus genus as gram-positive bacteria and using a chemical like cetyltrimethyl ammonium bromide for the Mycobacterium genus. In this study, we planned to use sand particles for the mechanical elimination of the cell wall without any need for chemicals and we called this procedure as "sand method". For the purpose of DNA extraction, the fine-grained sand was washed with ddH(2)O without losing small particles and then sterilized by autoclaving. For the purpose of RNA extraction; the sand was washed with ddH(2)O, incubated for 30 minutes with 10% HCl, and then autoclaved. A methicillin-resistant Staphylococcus aureus (MRSA) strain previously isolated and identified from a clinical specimen was mixed in 100 µl Tris-EDTA buffer with 100 mg sand. The mixture of bacteria and sand was vortexed at the maximum speed for 5 minutes. The MRSA-sand mix was treated with proteinase K and phenol-chloroform, and ethanol precipitation protocol was then followed for obtaining DNA. For comparison of the sand method with the other methods, the same amount of bacteria used in the sand method was incubated for one hour with lysostaphin, and then the proteinase K DNA extraction method were completed in the same

  3. [A new method for the disruption of cell walls of gram-positive bacteria and mycobacteria on the point of nucleic acid extraction: sand method].

    PubMed

    Şahin, Fikret; Kıyan, Mehmet; Karasartova, Djursun; Çalgın, M Kerem; Akhter, Shameem; Türegün Atasoy, Buse

    2016-01-01

    Nowadays molecular methods are widely used in the rapid diagnosis of infectious agents. Polymerase chain reaction (PCR) is the most preferred method for this purpose. Obtaining sufficient and pure DNA or RNA is important for the PCR. Different DNA extraction protocols such as phenol-chloroform, proteinase K, glass beads and boiling have been used successfully for DNA isolation from gram-negative bacteria. However since gram-positive bacteria have a thicker layer of peptidoglycan and mycobacteria have complex glycolipids in their cell walls, for the isolation of DNA or RNA from these microorganisms, the complex cell wall structure must be eliminated. For this purpose, the bacterial cell wall must be completely or partially removed forming sferoblast using lysostaphin in the Staphylococcus genus as gram-positive bacteria and using a chemical like cetyltrimethyl ammonium bromide for the Mycobacterium genus. In this study, we planned to use sand particles for the mechanical elimination of the cell wall without any need for chemicals and we called this procedure as "sand method". For the purpose of DNA extraction, the fine-grained sand was washed with ddH(2)O without losing small particles and then sterilized by autoclaving. For the purpose of RNA extraction; the sand was washed with ddH(2)O, incubated for 30 minutes with 10% HCl, and then autoclaved. A methicillin-resistant Staphylococcus aureus (MRSA) strain previously isolated and identified from a clinical specimen was mixed in 100 µl Tris-EDTA buffer with 100 mg sand. The mixture of bacteria and sand was vortexed at the maximum speed for 5 minutes. The MRSA-sand mix was treated with proteinase K and phenol-chloroform, and ethanol precipitation protocol was then followed for obtaining DNA. For comparison of the sand method with the other methods, the same amount of bacteria used in the sand method was incubated for one hour with lysostaphin, and then the proteinase K DNA extraction method were completed in the same

  4. Growing self-reconstruction maps.

    PubMed

    do Rêgo, Renata Lúcia Mendonça Ernesto; Araújo, Aluizio Fausto Ribeiro; de Lima Neto, Fernando Buarque

    2010-02-01

    In this paper, we propose a new method for surface reconstruction based on growing self-organizing maps (SOMs), called growing self-reconstruction maps (GSRMs). GSRM is an extension of growing neural gas (GNG) that includes the concept of triangular faces in the learning algorithm and additional conditions in order to include and remove connections, so that it can produce a triangular two-manifold mesh representation of a target object given an unstructured point cloud of its surface. The main modifications concern competitive Hebbian learning (CHL), the vertex insertion operation, and the edge removal mechanism. The method proposed is able to learn the geometry and topology of the surface represented in the point cloud and to generate meshes with different resolutions. Experimental results show that the proposed method can produce models that approximate the shape of an object, including its concave regions, boundaries, and holes, if any. PMID:20007030

  5. Management of growing vestibular schwannomas.

    PubMed

    Ferri, Gian Gaetano; Pirodda, Antonio; Ceroni, Alberto Rinaldi; Fioravanti, Antonio; Calbucci, Fabio; Modugno, Giovanni Carlo

    2013-07-01

    Conservative management of small vestibular schwannomas is frequently proposed as most tumours do not grow. Anyway, tumour growth is reported in 30-40 % of the cases, so that surgery is consequently generally proposed. We primarily observed 161 patients affected by unilateral vestibular schwannomas. All patients were examined by means of gadolinium-enhanced magnetic resonance imaging scans. Tumour growth was recorded in 58 cases (35.8 %) and these subjects set up the group of study. Twenty-two (37.9 %) patients were surgically treated; tumour was always completely removed, all patients had normal facial function after surgery and only one patient suffered from a major complication (cerebellar haematoma). Fourteen patients (24.1 %) were submitted to radiotherapy, while one patient was lost at follow-up and another one died because of other medical reasons. Finally, 20 (34.5 %) subjects continued to be observed for different reasons. The mean follow-up period after identification of growth was 6.1 years. Nine tumours continued to grow, nine tumours stopped growing, one tumour grew and then regressed in size and one tumour decreased. Sixty percent of patients with useful hearing at diagnosis preserved it during the entire observation period. In conclusion, most of VS do not grow; in case of tumour growth, a surgical procedure may be suggested and the outcomes are not negatively influenced by the delay of the procedure. But in some cases, patients can still follow the "wait and scan" policy. In fact, only less than half of the growing tumours continued to grow. Moreover, most of the patients continued to retain a useful hearing. PMID:23135237

  6. Kinderland in the Fatherland: Growing Children in Imperial Berlin

    ERIC Educational Resources Information Center

    Brian, Amanda

    2009-01-01

    This dissertation explores the milieu in which children of Imperial Berlin were raised. When contemporaries in the rapidly expanding capital of the Second German Empire (1871-1918) looked at children, this milieu darkened. The city, they argued, threatened children's growing bodies, and such institutions as the home, the clinic, and the school…

  7. [The presence of mycobacteria in bronchoalveolar lavage fluid from an immunocompetent patient does not necessarily imply tuberculosis].

    PubMed

    Vandenbos, Frédéric; Marcq, Laurent; Novellas, Sébastien; Chyderiotis, Georges; Haudebourg, Juliette; Benchetrit, Maxime; Burel-Vandenbos, Fanny

    2009-12-01

    Mycobacterium tuberculosis is the most frequently identified mycobacterium in the bronchoalveolar lavage fluid (BALF) of immunocompetent patients. Lung infections due to non-tuberculous mycobacteria (NTM) are rare in such patients and then often occur in the context of pre-existing chronic lung disease. We report the case of an immunocompetent 85-year-old woman without pre-existing lung disease in whom M. abscessus was recovered from BALF. Cytological examination of the BALF revealed an increased number of neutrophils and some acid-fast bacilli, all located within neutrophil cytoplasm. This case report contributes a cytological description of BALF in the context of M. abscessus infection, which is poorly detailed in the literature. PMID:20005441

  8. Rapid Antibiotic Resistance Evolution of GASP Mutants

    NASA Astrophysics Data System (ADS)

    Zhang, Qiucen; Kim, Hyunsung; Pourmand, Nader; Austin, Robert

    2012-02-01

    The GASP phenotype in bacteria is due to a mutation which enables the bacteria to grow under high stress conditions where other bacteria stop growing. We probe using our Death Galaxy microenvironment how rapidly the GASP mutant can evolve resistance to mutagenic antibiotics compared to wild-type bacteria, and explore the genomic landscape changes due to the evolution of resistance.

  9. Extreme Mechanics of Growing Matter

    NASA Astrophysics Data System (ADS)

    Kuhl, Ellen

    2013-03-01

    Growth is a distinguishing feature of all living things. Unlike standard materials, living matter can autonomously respond to alterations in its environment. As a result of a continuous ultrastructural turnover and renewal of cells and extracellular matrix, living matter can undergo extreme changes in composition, size, and shape within the order of months, weeks, or days. While hard matter typically adapts by increasing its density to grow strong, soft matter adapts by increasing its volume to grow large. Here we provide a state-of-the-art review of growing matter, and compare existing mathematical models for growth and remodeling of living systems. Applications are plentiful ranging from plant growth to tumor growth, from asthma in the lungs to restenosis in the vasculature, from plastic to reconstructive surgery, and from skeletal muscle adaptation to heart failure. Using these examples, we discuss current challenges and potential future directions. We hope to initiate critical discussions around the biophysical modeling of growing matter as a powerful tool to better understand biological systems in health and disease. This research has been supported by the NSF CAREER award CMMI 0952021.

  10. How the pilidium larva grows

    PubMed Central

    2014-01-01

    Background For animal cells, ciliation and mitosis appear to be mutually exclusive. While uniciliated cells can resorb their cilium to undergo mitosis, multiciliated cells apparently can never divide again. Nevertheless, many multiciliated epithelia in animals must grow or undergo renewal. The larval epidermis in a number of marine invertebrate larvae, such as those of annelids, mollusks and nemerteans, consists wholly or in part of multiciliated epithelial cells, generally organized into a swimming and feeding apparatus. Many of these larvae must grow substantially to reach metamorphosis. Do individual epithelial cells simply expand to accommodate an increase in body size, or are there dividing cells amongst them? If some cells divide, where are they located? Results We show that the nemertean pilidium larva, which is almost entirely composed of multiciliated cells, retains pockets of proliferative cells in certain regions of the body. Most of these are found near the larval ciliated band in the recesses between the larval lobes and lappets, which we refer to as axils. Cells in the axils contribute both to the growing larval body and to the imaginal discs that form the juvenile worm inside the pilidium. Conclusions Our findings not only explain how the almost-entirely multiciliated pilidium can grow, but also demonstrate direct coupling of larval and juvenile growth in a maximally-indirect life history. PMID:24690541

  11. Growing an Emerging Research University

    ERIC Educational Resources Information Center

    Birx, Donald L.; Anderson-Fletcher, Elizabeth; Whitney, Elizabeth

    2013-01-01

    The emerging research college or university is one of the most formidable resources a region has to reinvent and grow its economy. This paper is the first of two that outlines a process of building research universities that enhance regional technology development and facilitate flexible networks of collaboration and resource sharing. Although the…

  12. Exploring Classroom Hydroponics. Growing Ideas.

    ERIC Educational Resources Information Center

    National Gardening Association, Burlington, VT.

    Growing Ideas, the National Gardening Association's series for elementary, middle, and junior high school educators, helps teachers engage students in using plants and gardens as contexts for developing a deeper, richer understanding of the world around them. This volume's focus is on hydroponics. It presents basic hydroponics information along…

  13. Colleges' Earmarks Grow, Amid Criticism

    ERIC Educational Resources Information Center

    Brainard, Jeffrey; Hermes, J. J.

    2008-01-01

    A record-breaking number of Congressional pork-barrel projects this year has loaded college and university plates with more earmarks than ever before, despite growing worries that the noncompetitive grants undermine the American scientific enterprise, and in spite of promises by some lawmakers to cut back. An analysis by "The Chronicle" shows that…

  14. Growing Crystals on the Ceiling.

    ERIC Educational Resources Information Center

    Christman, Robert A.

    1980-01-01

    Described is a method of studying growing crystals in a classroom utilizing a carrousel projector standing vertically. A saturated salt solution is placed on a slide on the lens of the projector and the heat from the projector causes the water to evaporate and salt to crystalize. (Author/DS)

  15. Growing Crystals for Infrared Detectors

    NASA Technical Reports Server (NTRS)

    Lehoczky, S. L.; Szofran, F. R.

    1984-01-01

    Unidirectional solidification yields bulk crystals with compositional homogeneity. Unidirectionaly crystal-growth furnace assembly travels vertically so crystal grows upward from bottom tapered end of ampoule. Separately controlled furnaces used for hot (upper) and cold (lower) zones. New process produces ingots with radial compositional homogeneity suitable for fabricating infrared detectors.

  16. Consequences of Growing Up Poor.

    ERIC Educational Resources Information Center

    Duncan, Greg J., Ed.; Brooks-Gunn, Jeanne, Ed.

    The consequences and correlates of growing up poor as well as the mechanisms through which poverty influences children are explored. This book is organized with a primary focus on research findings and a secondary concern with policy implications. The chapters are: (1) "Poor Families, Poor Outcomes: The Well-Being of Children and Youth" (Jeanne…

  17. Growing Patterns: Seeing beyond Counting

    ERIC Educational Resources Information Center

    Markworth, Kimberly A.

    2012-01-01

    Over the past two decades, mathematical patterns have been acknowledged as important early components of children's development of algebraic reasoning (NCTM 2000). In particular, growing patterns have attracted significant attention as a context that helps students develop an understanding of functional relationships (Lee and Freiman 2006; Moss et…

  18. Growing Ideas, 1990-1993.

    ERIC Educational Resources Information Center

    Pranis, Eve, Ed.

    1993-01-01

    This series of journals includes volumes 1-4 of "Growing Ideas," a journal of garden-based learning. Each issue provides instructional ideas, horticultural information and a forum for exchange among teachers using classroom gardening to stimulate learning. Ideas in each issue are separated into three sections. The "Green Tips" section presents…

  19. Organization of growing random networks

    SciTech Connect

    Krapivsky, P. L.; Redner, S.

    2001-06-01

    The organizational development of growing random networks is investigated. These growing networks are built by adding nodes successively, and linking each to an earlier node of degree k with an attachment probability A{sub k}. When A{sub k} grows more slowly than linearly with k, the number of nodes with k links, N{sub k}(t), decays faster than a power law in k, while for A{sub k} growing faster than linearly in k, a single node emerges which connects to nearly all other nodes. When A{sub k} is asymptotically linear, N{sub k}(t){similar_to}tk{sup {minus}{nu}}, with {nu} dependent on details of the attachment probability, but in the range 2{lt}{nu}{lt}{infinity}. The combined age and degree distribution of nodes shows that old nodes typically have a large degree. There is also a significant correlation in the degrees of neighboring nodes, so that nodes of similar degree are more likely to be connected. The size distributions of the in and out components of the network with respect to a given node{emdash}namely, its {open_quotes}descendants{close_quotes} and {open_quotes}ancestors{close_quotes}{emdash}are also determined. The in component exhibits a robust s{sup {minus}2} power-law tail, where s is the component size. The out component has a typical size of order lnt, and it provides basic insights into the genealogy of the network.

  20. Mycobacterium tuberculosis Proteins Involved in Mycolic Acid Synthesis and Transport Localize Dynamically to the Old Growing Pole and Septum

    PubMed Central

    Cantaloube, Sylvain; Bonne, Mélanie; Diagne, Cheikh T.; Laval, Françoise; Daffé, Mamadou; Zerbib, Didier

    2014-01-01

    Understanding the mechanism that controls space-time coordination of elongation and division of Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), is critical for fighting the tubercle bacillus. Most of the numerous enzymes involved in the synthesis of Mycolic acid - Arabinogalactan-Peptidoglycan complex (MAPc) in the cell wall are essential in vivo. Using a dynamic approach, we localized Mtb enzymes belonging to the fatty acid synthase-II (FAS-II) complexes and involved in mycolic acid (MA) biosynthesis in a mycobacterial model of Mtb: M. smegmatis. Results also showed that the MA transporter MmpL3 was present in the mycobacterial envelope and was specifically and dynamically accumulated at the poles and septa during bacterial growth. This localization was due to its C-terminal domain. Moreover, the FAS-II enzymes were co-localized at the poles and septum with Wag31, the protein responsible for the polar localization of mycobacterial peptidoglycan biosynthesis. The dynamic localization of FAS-II and of the MA transporter with Wag31, at the old-growing poles and at the septum suggests that the main components of the mycomembrane may potentially be synthesized at these precise foci. This finding highlights a major difference between mycobacteria and other rod-shaped bacteria studied to date. Based on the already known polar activities of envelope biosynthesis in mycobacteria, we propose the existence of complex polar machinery devoted to the biogenesis of the entire envelope. As a result, the mycobacterial pole would represent the Achilles' heel of the bacillus at all its growing stages. PMID:24817274

  1. Fast-growing willow shrub named `Canastota`

    DOEpatents

    Abrahamson, Lawrence P.; Kopp, Richard F.; Smart, Lawrence B.; Volk, Timothy A.

    2007-05-15

    A distinct male cultivar of Salix sachalinensis.times.S. miyabeana named `Canastota`, characterized by rapid stem growth producing greater than 2.7-fold more woody biomass than its female parent (Salix sachalinensis `SX61`), 28% greater woody biomass yield than its male parent (Salix miyabeana `SX64`), and 20% greater woody biomass yield than a standard production cultivar, Salix dasyclados `SV1` when grown in the same field for the same length of time (two growing seasons after coppice) in Tully, N.Y. `Canastota` can be planted from dormant stem cuttings, produces multiple stems after coppice, and the stem biomass can be harvested when the plant is dormant. In the spring following harvest, the plant will re-sprout very vigorously, producing new stems that can be harvested after two to four years of growth. This harvest cycle can be repeated several times. `Canastota` displays a low incidence of rust disease or damage by willow sawfly.

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

    PubMed

    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

  3. Silicone Granulomas, a Growing Problem?

    PubMed Central

    Curreri, Alexis T.; Taylor, Gina A.; Burris, Katy

    2016-01-01

    The formation of granulomas is known to be a possible adverse effect of liquid silicone administration, used for soft tissue augmentation. Its plumping effects provide enhancement of certain body parts, such as the lips, hips, and buttocks. The desire for enhancement, perhaps influenced by popular culture and an unrealistic standard of beauty, leads individuals to seek silicone injections. There is a growing population of women and men receiving injections by unlicensed, unskilled “practitioners” not related to the healthcare profession. Complications under such circumstances are not uncommon, particularly the emergence of silicone granulomas, and the authors’ medical center has seen an increase in such cases. In this case report, the authors illustrate a young patient with significant complications from her silicone injections, review current therapies for silicone granulomas, and discuss this growing medical problem. PMID:27386046

  4. Silicone Granulomas, a Growing Problem?

    PubMed

    Park, Michelle E; Curreri, Alexis T; Taylor, Gina A; Burris, Katy

    2016-05-01

    The formation of granulomas is known to be a possible adverse effect of liquid silicone administration, used for soft tissue augmentation. Its plumping effects provide enhancement of certain body parts, such as the lips, hips, and buttocks. The desire for enhancement, perhaps influenced by popular culture and an unrealistic standard of beauty, leads individuals to seek silicone injections. There is a growing population of women and men receiving injections by unlicensed, unskilled "practitioners" not related to the healthcare profession. Complications under such circumstances are not uncommon, particularly the emergence of silicone granulomas, and the authors' medical center has seen an increase in such cases. In this case report, the authors illustrate a young patient with significant complications from her silicone injections, review current therapies for silicone granulomas, and discuss this growing medical problem. PMID:27386046

  5. Growing a miracle in Kenya.

    PubMed

    Farruggia, Michael J

    2013-01-01

    A Kenyan woman, a retired nurse, and a nurse executive in America are miraculously led together to start a library in Kima, Kenya. Small beginnings grow into the Heather May-MashoodAbiola Children's Resource Centre (HEMAMA). Named after two infant children lost by the Kenyan woman and the nurse executive, HEMAMA is making a difference in the lives of children in the Kima, Kenya community.

  6. Role of intragenic binding of cAMP responsive protein (CRP) in regulation of the succinate dehydrogenase genes Rv0249c-Rv0247c in TB complex mycobacteria

    PubMed Central

    Knapp, Gwendowlyn S.; Lyubetskaya, Anna; Peterson, Matthew W.; Gomes, Antonio L.C.; Ma, Zhuo; Galagan, James E.; McDonough, Kathleen A.

    2015-01-01

    Bacterial pathogens adapt to changing environments within their hosts, and the signaling molecule adenosine 3′, 5′-cyclic monophosphate (cAMP) facilitates this process. In this study, we characterized in vivo DNA binding and gene regulation by the cAMP-responsive protein CRP in M. bovis BCG as a model for tuberculosis (TB)-complex bacteria. Chromatin immunoprecipitation followed by deep-sequencing (ChIP-seq) showed that CRP associates with ∼900 DNA binding regions, most of which occur within genes. The most highly enriched binding region was upstream of a putative copper transporter gene (ctpB), and crp-deleted bacteria showed increased sensitivity to copper toxicity. Detailed mutational analysis of four CRP binding sites upstream of the virulence-associated Rv0249c-Rv0247c succinate dehydrogenase genes demonstrated that CRP directly regulates Rv0249c-Rv0247c expression from two promoters, one of which requires sequences intragenic to Rv0250c for maximum expression. The high percentage of intragenic CRP binding sites and our demonstration that these intragenic DNA sequences significantly contribute to biologically relevant gene expression greatly expand the genome space that must be considered for gene regulatory analyses in mycobacteria. These findings also have practical implications for an important bacterial pathogen in which identification of mutations that affect expression of drug target-related genes is widely used for rapid drug resistance screening. PMID:25940627

  7. Growing yeast into cylindrical colonies.

    PubMed

    Vulin, Clément; Di Meglio, Jean-Marc; Lindner, Ariel B; Daerr, Adrian; Murray, Andrew; Hersen, Pascal

    2014-05-20

    Microorganisms often form complex multicellular assemblies such as biofilms and colonies. Understanding the interplay between assembly expansion, metabolic yield, and nutrient diffusion within a freely growing colony remains a challenge. Most available data on microorganisms are from planktonic cultures, due to the lack of experimental tools to control the growth of multicellular assemblies. Here, we propose a method to constrain the growth of yeast colonies into simple geometric shapes such as cylinders. To this end, we designed a simple, versatile culture system to control the location of nutrient delivery below a growing colony. Under such culture conditions, yeast colonies grow vertically and only at the locations where nutrients are delivered. Colonies increase in height at a steady growth rate that is inversely proportional to the cylinder radius. We show that the vertical growth rate of cylindrical colonies is not defined by the single-cell division rate, but rather by the colony metabolic yield. This contrasts with cells in liquid culture, in which the single-cell division rate is the only parameter that defines the population growth rate. This method also provides a direct, simple method to estimate the metabolic yield of a colony. Our study further demonstrates the importance of the shape of colonies on setting their expansion. We anticipate that our approach will be a starting point for elaborate studies of the population dynamics, evolution, and ecology of microbial colonies in complex landscapes. PMID:24853750

  8. Growing crystals from eutectic melts

    NASA Technical Reports Server (NTRS)

    Bhat, B. N.

    1976-01-01

    Inverted Bridgman Method yields crystals of higher homogeneity and better structure than those grown by ordinary Bridgman method. Process controls thermotransport by holding molten alloy in known temperature for known period of time. Rapid cooling quenches in state of segregation. Method is applicable to other eutectiferous systems where thermotransport is appreciable.

  9. Draft Genome Sequences of Six Mycobacterium immunogenum, Strains Obtained from a Chloraminated Drinking Water Distribution System Simulator

    EPA Science Inventory

    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...

  10. Cultural systems for growing potatoes in space

    NASA Technical Reports Server (NTRS)

    Tibbitts, T.; Bula, R.; Corey, R.; Morrow, R.

    1988-01-01

    Higher plants are being evaluated for life support to provide needed food, oxygen and water as well as removal of carbon dioxide from the atmosphere. The successful utilization of plants in space will require the development of not only highly productive growing systems but also highly efficient bioregenerative systems. It will be necessary to recycle all inedible plant parts and all human wastes so that the entire complement of elemental compounds can be reused. Potatoes have been proposed as one of the desirable crops because they are 1) extremely productive, yielding more than 100 metric tons per hectare from field plantings, 2) the edible tubers are high in digestible starch (70%) and protein (10%) on a dry weight basis, 3) up to 80% of the total plant production is in tubers and thus edible, 4) the plants are easily propagated either from tubers or from tissue culture plantlets, 5) the tubers can be utilized with a minimum of processing, and 6) potatoes can be prepared in a variety of different forms for the human diet (Tibbitts et al., 1982). However potatoes have a growth pattern that complicates the development of growing the plants in controlled systems. Tubers are borne on underground stems that are botanically termed 'rhizomes', but in common usage termed 'stolons'. The stolons must be maintained in a dark, moist area with sufficient provision for enlargement of tubers. Stems rapidly terminate in flowers forcing extensive branching and spreading of plants so that individual plants will cover 0.2 m2 or more area. Thus the growing system must be developed to provide an area that is darkened for tuber and root growth and of sufficient size for plant spread. A system developed for growing potatoes, or any plants, in space will have certain requirements that must be met to make them a useful part of a life support system. The system must 1) be constructed of materials, and involve media, that can be reused for many successive cycles of plant growth, 2

  11. Evaluation of peptide nucleic acid-fluorescence in situ hybridization for identification of clinically relevant mycobacteria in clinical specimens and tissue sections.

    PubMed

    Lefmann, Michael; Schweickert, Birgitta; Buchholz, Petra; Göbel, Ulf B; Ulrichs, Timo; Seiler, Peter; Theegarten, Dirk; Moter, Annette

    2006-10-01

    With fluorescently labeled PNA (peptide nucleic acid) probes targeting 16S rRNA, we established a 3-h fluorescence in situ hybridization (FISH) procedure for specific visualization of members of the Mycobacterium tuberculosis complex, M. leprae, M. avium, and M. kansasii. Probe specificity was tested against a panel of 25 Mycobacterium spp. and 10 gram-positive organisms. After validation, probes were used to identify 52 mycobacterial culture isolates. Results were compared to conventional genotypic identification with amplification-based methods. All isolates (M. tuberculosis complex, n = 24; M. avium, n = 7; M. kansasii, n = 1) were correctly identified by FISH. In addition, the technique was used successfully for visualization of mycobacteria in biopsies from infected humans or animals. In conclusion, PNA-FISH is a fast and accurate tool for species-specific identification of culture-grown mycobacteria and for direct visualization of these organisms in tissue sections. It may be used successfully for both research and clinical microbiology.

  12. Monoclonal antibodies to surface antigens of Mycobacterium tuberculosis and their use in a modified enzyme-linked immunosorbent spot assay for detection of mycobacteria.

    PubMed Central

    Glatman-Freedman, A; Martin, J M; Riska, P F; Bloom, B R; Casadevall, A

    1996-01-01

    Three monoclonal antibodies (MAbs) were generated from splenocytes of a BALB/c mouse immunized with heat-killed Mycobacterium tuberculosis. All three MAbs bound to surface epitopes of M. tuberculosis as shown by whole-cell enzyme-linked immunosorbent assay (ELISA), indirect immunofluorescence, and immunoelectron microscopy. One immunoglobulin M (IgM) MAb bound to lipoarabinomannan, the second IgM MAb bound to mycolyl-arabinogalactan-peptidoglycan complex, and the third MAb, an IgG3, bound to a surface epitope of an uncertain nature. The MAbs demonstrated different cross-reactivity patterns with other mycobacteria. Two of the MAbs were used to develop a modified ELISA spot assay for the detection of mycobacteria. PMID:8897185

  13. Co-infection of long-standing extensively drug-resistant Mycobacterium tuberculosis (XDR-TB) and non-tuberculosis mycobacteria: A case report.

    PubMed

    Izadi, Nafiseh; Derakhshan, Mohammad; Samiei, Amin; Ghazvini, Kiarash

    2015-01-01

    We report a 69-years-old Iranian HIV negative male patient, with long-standing pulmonary tuberculosis (eleven years) co-infected with non-tuberculosis mycobacteria. Despite of initiation of first line anti-tuberculosis therapy after diagnosis the patient poorly respond because of low compliance with anti-TB treatment. After several incomplete treatments the smear was still positive and thus drug susceptibility tests were performed on isolated organism which revealed that the organisms was resistant not only against isoniazid and rifampin but also against Ofloxacin (OFX), Capreomycin (CAP), p-aminosalicylic acid (PAS), ethionamide (ETH), Kanamycin (KAN), ciprofloxacin (Cip), amikacin (AMK) and cycloserine (CYC). Persistence and resistance of infection had led us to do more investigation using molecular methods, which revealed co-infection with Non-tuberculosis mycobacteria (NTM). The patient is still alive with cough and shortness of breath. PMID:26236585

  14. [Physical activity among growing children].

    PubMed

    Tammelin, Tuija; Iljukov, Sergei; Parkkari, Jari

    2015-01-01

    Lack of physical activity poses a risk to the health and well-being of growing children, and should also be considered at a medical consultation. According to recommendations, those of 7 to 18 years of age should carry out at least one hour of physical activity daily. Of the Finnish school-aged children, 50% of the elementary school children but only 17% of the secondary school children follow the physical activity recommendations. Some children exercise and play sports in abundance, and in their case it should be especially made sure that the prevention and, when necessary, treatment of exercise-related injuries, overexertion and eating disorders are taken care of.

  15. Synchronization in growing heterogeneous media

    NASA Astrophysics Data System (ADS)

    Chen, W.; Cheng, S. C.; Avalos, E.; Drugova, O.; Osipov, G.; Lai, Pik-Yin; Chan, C. K.

    2009-04-01

    Synchronization of heterogeneous systems that consist of oscillatory and passive elements are studied in cardiac myocytes/fibroblasts co-cultures. It is found that beating clusters of cardiac myocytes surrounded by fibroblasts will be formed. The beatings of the cardiac myocyte clusters are not correlated at early times, but get synchronized as the cultures mature. This synchronization can be understood by a Kuramoto model with a time-increasing coupling strength. Our findings show that the growth of the coupling strength between clusters is linear, while the overall wave dynamics of the system is controlled by the passive fibroblast in the system which presumably is growing exponentially.

  16. What makes active regions grow.

    NASA Technical Reports Server (NTRS)

    Weart, S.

    1972-01-01

    A study of magnetic flux growth or growth failure in over 100 active regions is shown to indicate that most growth is connected with the emergence of a large batch of flux in the shape of a new arch filament system (AFS). During the recent sunspot maximum, new AFSs appeared at a rate of nearly one per day over the entire sun. Evidence is presented for two proposed hypotheses, namely: (1) a twist in the flux tubes of new AFSs is a key factor in determining which new AFSs will grow; and (2) this twist is related to the well-known asymmetry of sunspot groups.

  17. Metal bioremediation through growing cells.

    PubMed

    Malik, Anushree

    2004-04-01

    Heavy-metal pollution represents an important environmental problem due to the toxic effects of metals, and their accumulation throughout the food chain leads to serious ecological and health problems. Metal remediation through common physico-chemical techniques is expensive and unsuitable in case of voluminous effluents containing complexing organic matter and low metal contamination. Biotechnological approaches that are designed to cover such niches have, therefore, received great deal of attention in the recent years. Biosorption studies involving low-cost and often dead/pretreated biomass have dominated the literature and, subsequently, extensive reviews focusing on equilibrium and kinetics of metal biosorption have also come up. However, the low binding capacity of biomass for certain recalcitrant metals such as Ni and failure to effectively remove metals from real industrial effluents due to presence of organic or inorganic ligands limit this approach. At times, when pure biosorptive metal removal is not feasible, application of a judicious consortium of growing metal-resistant cells can ensure better removal through a combination of bioprecipitation, biosorption and continuous metabolic uptake of metals after physical adsorption. Such approach may lead to simultaneous removal of toxic metals, organic loads and other inorganic impurities, as well as allow optimization through development of resistant species. However, sensitivity of living cells to extremes of pH or high metal concentration and need to furnish metabolic energy are some of the major constraints of employing growing cells for bioremediation. The efforts to meet such challenges via isolation of metal-resistant bacterial/fungal strains and exploitation of organic wastes as carbon substrates have began. Recent studies show that the strains (bacteria, yeast and fungi) isolated from contaminated sites possess excellent capability of metal scavenging. Some bacterial strains possess high tolerance to

  18. Mycobacteria-responsive sonic hedgehog signaling mediates programmed death-ligand 1- and prostaglandin E2-induced regulatory T cell expansion

    PubMed Central

    Holla, Sahana; Stephen-Victor, Emmanuel; Prakhar, Praveen; Sharma, Meenu; Saha, Chaitrali; Udupa, Vibha; Kaveri, Srinivas V.; Bayry, Jagadeesh; Balaji, Kithiganahalli Narayanaswamy

    2016-01-01

    CD4+CD25+FoxP3+ regulatory T cells (Tregs) are exploited by mycobacteria to subvert the protective host immune responses. The Treg expansion in the periphery requires signaling by professional antigen presenting cells and in particularly dendritic cells (DC). However, precise molecular mechanisms by which mycobacteria instruct Treg expansion via DCs are not established. Here we demonstrate that mycobacteria-responsive sonic hedgehog (SHH) signaling in human DCs leads to programmed death ligand-1 (PD-L1) expression and cyclooxygenase (COX)-2-catalyzed prostaglandin E2 (PGE2) that orchestrate mycobacterial infection-induced expansion of Tregs. While SHH-responsive transcription factor GLI1 directly arbitrated COX-2 transcription, specific microRNAs, miR-324-5p and miR-338-5p, which target PD-L1 were downregulated by SHH signaling. Further, counter-regulatory roles of SHH and NOTCH1 signaling during mycobacterial-infection of human DCs was also evident. Together, our results establish that Mycobacterium directs a fine-balance of host signaling pathways and molecular regulators in human DCs to expand Tregs that favour immune evasion of the pathogen. PMID:27080341

  19. Bath water contamination with Legionella and nontuberculous mycobacteria in 24-hour home baths, hot springs, and public bathhouses of Nagano Prefecture, Japan.

    PubMed

    Kobayashi, Michiko; Oana, Kozue; Kawakami, Yoshiyuki

    2014-01-01

    Bath water samples were collected from 116 hot springs, 197 public bathhouses, and 38 24-hour home baths in Nagano Prefecture, Japan, during the period of April 2009 to November 2011, for determining the presence and extent of contamination with Legionella and nontuberculous mycobacteria. Cultures positive for Legionella were observed in 123 of the 3,314 bath water samples examined. The distribution and abundance of Legionella and/or combined contamination with Legionella and nontuberculous mycobacteria were investigated to clarify the contamination levels. The abundance of Legionella was demonstrated to correlate considerably with the levels of combined contamination with Legionella and nontuberculous mycobacteria. Legionella spp. were obtained from 61% of the water samples from 24-hour home baths, but only from 3% of the samples from public bathhouses and hot springs. This is despite the fact that a few outbreaks of Legionnaires' disease in Nagano Prefecture as well as other regions of Japan have been traced to bath water contamination. The comparatively higher rate of contamination of the 24-hour home baths is a matter of concern. It is therefore advisable to routinely implement good maintenance of the water basins, particularly of the 24-hour home baths.

  20. Three-Dimensional In Vitro Models of Granuloma to Study Bacteria-Host Interactions, Drug-Susceptibility, and Resuscitation of Dormant Mycobacteria

    PubMed Central

    Fitzgerald, Liam E.; Abendaño, Naiara; Juste, Ramon A.

    2014-01-01

    Mycobacterium tuberculosis, Mycobacterium leprae, Mycobacterium bovis, and Mycobacterium avium subsp. paratuberculosis can survive within host macrophages in a dormant state, encased within an organized aggregate of immune host cells called granuloma. Granulomas consist of uninfected macrophages, foamy macrophages, epithelioid cells, and T lymphocytes accumulated around infected macrophages. Within granulomas, activated macrophages can fuse to form multinucleated giant cells, also called giant Langhans cells. A rim of T lymphocytes surrounds the core, and a tight coat of fibroblast closes the structure. Several in vivo models have been used to study granuloma's structure and function, but recently developed in vitro models of granuloma show potential for closer observation of the early stages of host's responses to live mycobacteria. This paper reviews culture conditions that resulted in three-dimensional granulomas, formed by the adhesion of cell populations in peripheral blood mononuclear cells infected with mycobacteria. The similarities of these models to granulomas encountered in clinical specimens include cellular composition, granulomas' cytokine production, and cell surface antigens. A reliable in vitro dormancy model may serve as a useful platform to test whether drug candidates can kill dormant mycobacteria. Novel drugs that target dormancy-specific pathways may shorten the current long, difficult treatments necessary to cure mycobacterial diseases. PMID:24967387

  1. What a Pain! Kids and Growing Pains

    MedlinePlus

    ... Here's Help White House Lunch Recipes What a Pain! Kids and Growing Pains KidsHealth > For Kids > What a Pain! Kids and ... something doctors call growing pains . What Are Growing Pains? Growing pains aren't a disease. You probably ...

  2. Evaluation of antibacterial and cytotoxic activity of Artemisia nilagirica and Murraya koenigii leaf extracts against mycobacteria and macrophages

    PubMed Central

    2014-01-01

    Background Artemisia nilagirica (Asteraceae) and Murraya koenigii (Rutaceae) are widely distributed in eastern region of India. Leaves of Artemisia nilagirica plant are used to treat cold and cough by the local tribal population in east India. Murraya koenigii is an edible plant previously reported to have an antibacterial activity. Pathogenic strains of mycobacteria are resistant to most of the conventional antibiotics. Therefore, it is imperative to identify novel antimycobacterial molecules to treat mycobacterial infection. Methods In this study, ethanol, petroleum ether and water extracts of Artemisia nilagirica and Murraya koenigii were tested for antibacterial activity against Mycobacterium smegmatis and Mycobacterium bovis BCG in synergy with first line anti-tuberculosis (TB) drugs, and for cytotoxic activities on mouse macrophage RAW264.7 cells. Antibacterial activity was determined by colony forming unit (CFU) assay. Intracellular survival assay was performed by infecting RAW264.7 cells with M. smegmatis before and after treatment with plant extracts. Cytotoxity was checked by MTT [3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide] assay. Genotoxicity was studied by DAPI staining and COMET assay using mouse macrophage RAW264.7 cell line. Cell apoptosis was checked by Annexin-V/FITC dual staining method. Reactive oxygen species and nitric oxide production was checked by DCFH staining and Griess reagent, respectively. Results Ethanol extracts of A. nilagirica (IC50 300 μg/ml) and M. koenigii (IC50 400 μg/ml) were found to be more effective against Mycobacterium smegmatis as compared to petroleum ether and water extracts. M. koenigii extract showed maximum activity against M. bovis BCG in combination with a first line anti-TB drug rifampicin. M. koenigii leaf extract also exerted more cytototoxic (IC50 20 μg/ml), genotoxic and apoptosis in mouse macrophage RAW 264.7 cell line. Treatment of mouse macrophages with A. nilagirica extract increased

  3. Degree distributions of growing networks.

    PubMed

    Krapivsky, P L; Rodgers, G J; Redner, S

    2001-06-01

    The in-degree and out-degree distributions of a growing network model are determined. The in-degree is the number of incoming links to a given node (and vice versa for out-degree). The network is built by (i) creation of new nodes which each immediately attach to a preexisting node, and (ii) creation of new links between preexisting nodes. This process naturally generates correlated in-degree and out-degree distributions. When the node and link creation rates are linear functions of node degree, these distributions exhibit distinct power-law forms. By tuning the parameters in these rates to reasonable values, exponents which agree with those of the web graph are obtained.

  4. How to grow great leaders.

    PubMed

    Ready, Douglas A

    2004-12-01

    Few leaders excel at both the unit and enterprise levels. More than ever, though, corporations need people capable of running business units, functions, or regions and focusing on broader company goals. It's up to organizations to develop leaders who can manage the inherent tensions between unit and enterprise priorities. Take the example of RBC Financial Group, one of the largest, most profitable companies in Canada. In the mid-1990's, RBC revamped its competitive strategy in a couple of ways. After the government announced that the Big Six banks in Canada could neither merge with nor acquire one another, RBC decided to grow through cross-border acquisitions. Additionally, because customers were starting to seek bundled products and services, RBC reached across its traditional stand-alone businesses to offer integrated solutions. These changes in strategy didn't elicit immediate companywide support. Instinctively, employees reacted against what would amount to a delicate balancing act: They would have to lift their focus out of their silos while continuing to meet unit goals. However, by communicating extensively with staff members, cross-fertilizing talent across unit boundaries, and targeting rewards to shape performance, RBC was able to cultivate rising leaders with the unit expertise and the enterprise vision to help the company fulfill its new aims. Growing such well-rounded leaders takes sustained effort because unit-enterprise tensions are quite real. Three common conditions reinforce these tensions. First, most organizational structures foster silo thinking and unimaginative career paths. Second, most companies lack venues for airing and resolving conflicts that arise when there are competing priorities. Third, many have misguided reward systems that pit unit performance against enterprise considerations. Such long-established patterns of organizational behavior are tough to break. Fortunately, as RBC discovered, people can be trained to think and work

  5. In vitro models that utilize hypoxia to induce non-replicating persistence in Mycobacteria.

    PubMed

    Sohaskey, Charles D; Voskuil, Martin I

    2015-01-01

    The Wayne model and Rapid Anaerobic Dormancy model are widely used methods to analyze the response of Mycobacterium tuberculosis to hypoxia and anaerobiosis. In these models tubercle bacilli are grown in sealed tubes in which bacilli aerobic respiration produces a temporal oxygen gradient. The gradual depletion of oxygen results in a non-replicating persistent culture capable of extended microaerobic and anaerobic survival. Here we describe both models used to induce hypoxic non-replicating persistence in M. tuberculosis. Additional techniques such as the isolation of RNA, the detection of nitrate reductase activity and ATP levels, and the determination of the NAD(+)/NADH ratio are described. PMID:25779317

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

    PubMed

    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.

  7. The Epidemiology and Geographic Distribution of Nontuberculous Mycobacteria Clinical Isolates from Sputum Samples in the Eastern Region of China

    PubMed Central

    Song, Honghuan; Li, Guoli; Liu, Qiao; Li, Yan; Zhu, Limei; Martinez, Leonardo; Lu, Wei

    2015-01-01

    Background Nontuberculous mycobacteria (NTM) have been reported to be increasing worldwide and its geographic distribution differs by region. The aim of this study was to describe the epidemiology and distribution of NTM in the eastern part of China. Methods Sputum samples were collected from 30 surveillance sites for tuberculosis drug resistance test from May 1, 2008 to December 31, 2008. Identification was performed using a biochemical test, multiplex PCR and GenoType Mycobacterium CM/AS assay. Results A total of 1779 smear positive clinical isolates were obtained, of which 60 (3.37%) were NTM. Five species/complex of NTM were identified; M. intracellulare was the predominated species (68.33%), followed by M. abscessus-M. immunogenum (13.33%), Mycobacterium spec. (10.00%), M. Kansasii (6.67%) and M. peregrinum-M. alvei-M. septicum (1.67%). Conclusion M. intracellulare was the main species of NTM in the eastern part of China and clinical physicians should pay more attention to NTM induced pulmonary disease. PMID:25775117

  8. Mixed infections of Corynebacterium pseudotuberculosis and non-tuberculous mycobacteria in South African antelopes presenting with tuberculosis-like lesions.

    PubMed

    Müller, Borna; de Klerk-Lorist, Lin-Mari; Henton, Marijke M; Lane, Emily; Parsons, Sven; Gey van Pittius, Nicolaas C; Kotze, Antoinette; van Helden, Paul D; Tanner, Manfred

    2011-01-27

    Routine meat inspection of antelope carcasses from a South African game reserve revealed a high prevalence of tuberculosis-like lesions. This study aimed to identify the causative agent of this disease and to describe its pathological features. In total, 139 antelopes were randomly harvested from the game reserve and subjected to meat inspection. Of these animals, 46 (33%) showed gross visible, tuberculosis-like lesions. Histopathological examination revealed the presence of encapsulated necrogranulomas in organs and/or lymph nodes of 22 of 27 animals tested. Tissue samples from lesions were processed for both non-selective bacterial culture and mycobacterial culture following decontamination. In non-selective cultures of lesions from 25 of 31 animals tested, Corynebacterium pseudotuberculosis was detected. Isolation of C. pseudotuberculosis was closely associated with the presence of necrogranulomas. In mycobacterial cultures of lesions from 9 of 41 animals tested, different species of non-tuberculous mycobacteria (NTMs) were detected. In 5 instances, depending on the culture procedure that was applied, either C. pseudotuberculosis or NTMs were isolated from the same tissue sample. Our results suggest that the disease has been caused by infections with C. pseudotuberculosis. In sub-Saharan Africa, the role of pathogens other than Mycobacterium bovis may be underestimated in causing tuberculosis-like lesions. In cases where potentially pathogenic NTMs are isolated from mycobacterial cultures of tuberculosis-like lesions, the non-use of additional non-selective culture techniques could lead to misinterpretations of the diagnostic test results.

  9. CarD integrates three functional modules to promote efficient transcription, antibiotic tolerance, and pathogenesis in mycobacteria.

    PubMed

    Garner, Ashley L; Weiss, Leslie A; Manzano, Ana Ruiz; Galburt, Eric A; Stallings, Christina L

    2014-08-01

    Although the basic mechanisms of prokaryotic transcription are conserved, it has become evident that some bacteria require additional factors to allow for efficient gene transcription. CarD is an RNA polymerase (RNAP)-binding protein conserved in numerous bacterial species and essential in mycobacteria. Despite the importance of CarD, its function at transcription complexes remains unclear. We have generated a panel of mutations that individually target three independent functional modules of CarD: the RNAP interaction domain, the DNA-binding domain, and a conserved tryptophan residue. We have dissected the roles of each functional module in CarD activity and built a model where each module contributes to stabilizing RNAP-promoter complexes. Our work highlights the requirement of all three modules of CarD in the obligate pathogen Mycobacterium tuberculosis, but not in Mycobacterium smegmatis. We also report divergent use of the CarD functional modules in resisting oxidative stress and pigmentation. These studies provide new information regarding the functional domains involved in transcriptional regulation by CarD while also improving understanding of the physiology of M. tuberculosis.

  10. CarD integrates three functional modules to promote efficient transcription, antibiotic tolerance, and pathogenesis in mycobacteria

    PubMed Central

    Garner, Ashley L.; Weiss, Leslie A.; Manzano, Ana Ruiz; Galburt, Eric A.; Stallings, Christina L.

    2014-01-01

    Summary Although the basic mechanisms of prokaryotic transcription are conserved, it has become evident that some bacteria require additional factors to allow for efficient gene transcription. CarD is an RNA polymerase (RNAP) binding protein conserved in numerous bacterial species and essential in mycobacteria. Despite the importance of CarD, its function at transcription complexes remains unclear. We have generated a panel of mutations that individually target three independent functional modules of CarD: the RNAP interaction domain, the DNA binding domain, and a conserved tryptophan residue. We have dissected the roles of each functional module in CarD activity and built a model where each module contributes to stabilizing RNAP-promoter complexes. Our work highlights the requirement of all three modules of CarD in the obligate pathogen Mycobacterium tuberculosis, but not in Mycobacterium smegmatis. We also report divergent use of the CarD functional modules in resisting oxidative stress and pigmentation. These studies provide new information regarding the functional domains involved in transcriptional regulation by CarD while also improving understanding of the physiology of M. tuberculosis. PMID:24962732

  11. Medical Management for the Treatment of Nontuberculous Mycobacteria Infection of the Parotid Gland: Avoiding Surgery May Be Possible

    PubMed Central

    Bouhabel, Sarah; Oughton, Matthew Thomas

    2016-01-01

    Infection with nontuberculous mycobacteria (NTM) is uncommon in the head and neck; therefore there is no clear consensus on treating these infections. Our objective was to report our experience with a unique case of NTM infection of the parotid in an immunocompetent patient, in order to determine appropriate management through our experience with this pathology. A 57-year-old man, known for numerous comorbid diseases, presented to our institution complaining of right parotid swelling and pain. A computed tomography (CT) of the neck showed a multiloculated collection in the inferior portion of the right parotid gland, compatible with abscess formation. This abscess was drained by interventional radiology (IR) but required repeat drainage twice due to lack of initial improvement. He was treated with several antibiotics as culture results initially indicated Gram-positive bacilli and then Mycobacterium species, with final identification by a reference laboratory as Mycobacterium abscessus. Imipenem was initiated with amikacin and clarithromycin. His infection clinically and radiologically resolved after 5 months of antibiotherapy. In our case, the patient improved following intravenous antibiotic therapy. Our experience demonstrates that appropriate antibiotherapy can lead to resolution of Mycobacterium abscessus infection in the parotid without the risks associated with surgical intervention. PMID:27340407

  12. Microbial side-chain cleavage of phytosterols by mycobacteria in vegetable oil/aqueous two-phase system.

    PubMed

    Xu, Yang-Guang; Guan, Yi-Xin; Wang, Hai-Qing; Yao, Shan-Jing

    2014-09-01

    Microbial side-chain cleavage of natural sterols to 4-androstene-3,17-dione (AD) and 1,4-androstadiene-3,17-dione (ADD) by Mycobacteria has received much attention in pharmaceutical industry, while low yield of the reaction owing to the strong hydrophobicity of sterols is a tough problem to be solved urgently. Eight kinds of vegetable oils, i.e., sunflower, peanut, corn, olive, linseed, walnut, grape seed, and rice oil, were used to construct oil/aqueous biphasic systems in the biotransformation of phytosterols by Mycobacterium sp. MB 3683 cells. The results indicated that vegetable oils are suitable for phytosterol biotransformation. Specially, the yield of AD carried out in sunflower biphasic system (phase ratio of 1:9, oil to aqueous) was greatly increased to 84.8 % with 10 g/L feeding concentration after 120-h transformation at 30 °C and 200 rpm. Distribution coefficients of AD in different oil/aqueous systems were also determined. Because vegetable oils are of low cost and because of their eco-friendly characters, there is a great potential for the application of oil/aqueous two-phase systems in bacteria whole cell biocatalysis.

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

    PubMed Central

    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

  14. Characterization of the fibronectin-attachment protein of Mycobacterium avium reveals a fibronectin-binding motif conserved among mycobacteria.

    PubMed

    Schorey, J S; Holsti, M A; Ratliff, T L; Allen, P M; Brown, E J

    1996-07-01

    Mycobacterium avium is an intracellular pathogen and a major opportunistic infectious agent observed in patients with acquired immune deficiency syndrome (AIDS). Evidence suggests that the initial portal of infection by M. avium is often the gastrointestinal tract. However, the mechanism by which the M. avium crosses the epithelial barrier is unclear. A possible mechanism is suggested by the ability of M. avium to bind fibronectin, an extracellular matrix protein that is a virulence factor for several extracellular pathogenic bacteria which bind to mucosal surfaces. To further characterize fibronectin binding by M. avium, we have cloned the M. avium fibronectin-attachment protein (FAP). The M. avium FAP (FAP-A) has an unusually large number of Pro and Ala residues (40% overall) and is 50% identical to FAP of both Mycobacterium leprae and Mycobacterium tuberculosis. Using recombinant FAP-A and FAP-A peptides, we show that two non-continuous regions in FAP-A bind fibronectin. Peptides from these regions and homologous sequences from M. leprae FAP inhibit fibronectin binding by both M. avium and Mycobacterium bovis Bacillus Calmette-Guerin (BCG). These regions have no homology to eukaryotic fibronectin-binding proteins and are only distantly related to fibronectin-binding peptides of Gram-positive bacteria. Nevertheless, these fibronectin-binding regions are highly conserved among the mycobacterial FAPs, suggesting an essential function for this interaction in mycobacteria infection of their metazoan hosts.

  15. Isolation and identification of Mycobacterium avium complex and other nontuberculosis mycobacteria from drinking-water in Basra governorate, Iraq.

    PubMed

    Al-Sulami, A A; Al-Taee, A M R; Wida'a, Q H

    2012-03-01

    This study aimed to determine the occurrence of Mycobacterium avium complex and other nontuberculous mycobacteria in drinking-water in Basra governorate, Iraq and their susceptibility to several antibiotics and the effect of 0.5 mg/L of chlorine on their survival. A total of 404 samples of drinking-water were collected from 33 different districts of the governorate from November 2006 to August 2007. Filtered samples were incubated for 7 days or less in a monophasic-biphasic culture setup of tuberculosis broth and Lowenstein-Jensen agar. The 252 isolates were identified as M. avium complex (21), M. marinum (15), M. kansasii (30), M. simiae (20), M. szulgai (19), M. xenopi (16), M. malmoense (11), M. fortuitum (37), M. chelonae (50) and M. abscessus (33). Isolates were tested for antibiotic susceptibility as well as their ability to tolerate chlorine at a concentration of 0.5 mg/L. The presence of these pathogenic bacteria in drinking-water renders the water unfit for human consumption.

  16. GroEL1: a dedicated chaperone involved in mycolic acid biosynthesis during biofilm formation in mycobacteria.

    PubMed

    Ojha, Anil; Anand, Mridula; Bhatt, Apoorva; Kremer, Laurent; Jacobs, William R; Hatfull, Graham F

    2005-12-01

    Mycobacteria are unusual in encoding two GroEL paralogs, GroEL1 and GroEL2. GroEL2 is essential--presumably providing the housekeeping chaperone functions--while groEL1 is nonessential, contains the attB site for phage Bxb1 integration, and encodes a putative chaperone with unusual structural features. Inactivation of the Mycobacterium smegmatis groEL1 gene by phage Bxb1 integration allows normal planktonic growth but prevents the formation of mature biofilms. GroEL1 modulates synthesis of mycolates--long-chain fatty acid components of the mycobacterial cell wall--specifically during biofilm formation and physically associates with KasA, a key component of the type II Fatty Acid Synthase involved in mycolic acid synthesis. Biofilm formation is associated with elevated synthesis of short-chain (C56-C68) fatty acids, and strains with altered mycolate profiles--including an InhA mutant resistant to the antituberculosis drug isoniazid and a strain overexpressing KasA--are defective in biofilm formation. PMID:16325580

  17. Effect of protozoan predation on relative abundance of fast- and slow-growing bacteria

    SciTech Connect

    Sinclair, J.L.; Alexander, M.

    1989-01-01

    Survival of six bacterial species with different growth rates was tested in raw sewage and sewage rendered free of protozoa. When the six species were inoculated at the same densities into sewage containing protozoa, the three slow-growing species were rapidly eliminated, and two of the three fast-growing species survived in detectable numbers. It is suggested that in environments with intense protozoan predation, protozoa may alter composition of bacterial communities by eliminating slow-growing bacteria.

  18. Combination of multiplex PCR with denaturing high-performance liquid chromatography for rapid detection of Mycobacterium genus and simultaneous identification of the Mycobacterium tuberculosis complex.

    PubMed

    Chen, Ru; Gao, Xiao-Bo; Liu, Zhi-Hui; Shen, Xiao-Bing; Guo, Ai-Zhen; Duan, Yan-Yu; Liu, Zhi-Ling; Wu, Xiao-Wei; Zhu, Dao-Zhong

    2013-09-01

    A new assay with the combination of multiplex polymerase chain reaction and denaturing high-performance liquid chromatography analysis was developed for simultaneous detection of Mycobacterium genus and identification of the Mycobacterium tuberculosis complex (MTC). Targeting at genus-specific 16S rRNA sequence of Mycobacterium and specific insertion elements IS6110 and IS1081 of MTC, the assay was validated with 84 strains covering 23 mycobacteria species and 30 strains of non-mycobacteria species. No cross reactivity was observed. Clinical application was carried out on 198 specimens (155 human sputum and 43 bovine tissue samples) and compared with culture. The multiplex assay detected all culture-positive (36 in number) and 35.2% (57/162) culture-negative specimens. The molecular assay was fast that could be completed within 1 h on purified DNA, with the limit of detection as 0.8-1.6 pg per reaction on DNA template. This work provided a useful laboratory tool for rapid identification of Mycobacterium and differentiation of MTC and nontuberculous mycobacteria.

  19. [Growing old differently: Transdisciplinary perspective].

    PubMed

    Zimmermann, H-P

    2015-04-01

    Growing old differently: the phrase is intended to call something other to mind than merely the fact that images and forms of old age and aging have multiplied and diversified to an enormous extent. The suggestion put forward here is that otherness (as opposed to mere differences) should be positively reinforced. In other words, it is not just a matter of noting different forms of old age and aging but more than this, of seeking out opportunities for aging differently. In order to explore this, the article follows an older strand of theory, which has recently come to be frequently quoted in gerontology: the phenomenology of difference as reasoned analytically by Lévinas and Sartre and applied to gerontology by Améry and de Beauvoir. Here, opportunities for aging crucially depend on the way we look at it, how we observe and describe it and not least, how gerontology frames it. A distinction is made between two perspectives and their associated consequences for old age: alienation and alterity. Alienation means looking at old age above all as a disconcerting "other", as a perplexing, problematic deviation from the norm of vitality. Alterity, by contrast, refers to different options for living life in old age: options to be explored and opened up in contradistinction to cultural or academic alienation. Not least, the article appeals for diversity in scholarly approaches and for cross-disciplinary perspectives.

  20. Growing plants on atoll soils

    SciTech Connect

    Stone, E L; Migvar, L; Robison, W L

    2000-02-16

    Many years ago people living on atolls depended entirely on foods gathered from the sea and reefs and grown on land. Only a few plants, such as coconut (ni), Pandanus (bob), and arrowroot (mok-mok), could be grown on the lower rainfall atolls, although adequate groundwater conditions also allowed taro (iaraj, kotak, wot) to be cultivated. On higher rainfall atolls, breadfruit (ma) was a major food source, and banana (binana, kepran), lime (laim), and taros (iaraj, kotak, wot) could be grown. The early atoll populations were experts in growing plants that were vital to sustaining their nutrition requirements and to providing materials for thatch, basketry, cordage, canoe construction, flowers, and medicine. They knew which varieties of food plants grew well or poorly on their atolls, how to propagate them, and where on their atoll they grew best. They knew the uses of most native plants and what the various woods were well suited for. Many varieties of Pandanus (bob) and breadfruit (ma) grew well with high rainfall, but only a few produced well on drier atolls. Such information had been passed down through the generations although some of it has been lost in the last century. Today there are new plants and new varieties of existing plants that can be grown on atolls. There are also new materials and information on how to grow both the old and new plants more effectively. However, there are also introduced weeds and pests to control. Today, there is also an acute need to grow more of the useful plants adapted to atolls. Increasing numbers of people living on an atoll without an equal increase in income or food production stretches the available food supplies. Much has been written about the poor conditions for plant growth on atolls. As compared with many places in the world where crops are grown, however, atolls can provide some highly favorable conditions. For instance, the driving force for plant growth is sunlight, and on atolls light is abundant throughout the