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Sample records for suspected active tuberculosis

  1. Response to region of difference 1 (RD1) epitopes in human immunodeficiency virus (HIV)-infected individuals enrolled with suspected active tuberculosis: a pilot study

    PubMed Central

    Vincenti, D; Carrara, S; Butera, O; Bizzoni, F; Casetti, R; Girardi, E; Goletti, D

    2007-01-01

    Tuberculosis is the most frequent co-infection in human immunodeficiency virus (HIV)-infected individuals, and which still presents diagnostic difficulties. Recently we set up an assay based on interferon (IFN)-γ response to region of difference 1 (RD1) peptides selected by computational analysis which is associated with active Mycobacterium tuberculosis replication. The objective of this study was to investigate the response to RD1 selected peptides in HIV-1-infected individuals in a clinical setting. The mechanisms of this immune response and comparison with other immune assays were also investigated. A total of 111 HIV-infected individuals with symptoms and signs consistent with active tuberculosis were enrolled prospectively. Interferon (IFN)-γ responses to RD1 selected peptides and recall antigens were evaluated by enzyme-linked immunospot assay. Results were correlated with CD4− T cell counts, individuals' characteristics, tuberculin skin test, QuantiFERON-TB Gold and T-SPOT.TB. Results from 21 (19%) individuals were indeterminate due to in vitro cell anergy. Among ‘non-anergic’ individuals, sensitivity for active tuberculosis of the assay based on RD1 selected peptides was 67% (24 of 36), specificity was 94% (three of 54). The assay also resulted positive in cases of extra-pulmonary and smear-negative pulmonary active tuberculosis. The response was mediated by CD4− effector/memory T cells and correlated with CD4− T cell counts, but not with plasma HIV-RNA load. Moreover, the RD1 selected peptides assay had the highest diagnostic odds ratio for active tuberculosis compared to tuberculin skin test (TST), QuantiFERON-TB Gold and T-SPOT.TB. RD1 selected peptides assay is associated with M. tuberculosis replication in HIV-infected individuals, although T cell anergy remains an important obstacle to be overcome before the test can be proposed as a diagnostic tool. PMID:17680823

  2. 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

  3. Comparison of cortisol and thyroid hormones between tuberculosis-suspect and healthy elephants of Nepal

    PubMed Central

    PAUDEL, Sarad; BROWN, Janine L.; THAPALIYA, Sharada; DHAKAL, Ishwari P.; MIKOTA, Susan K.; GAIRHE, Kamal P.; SHIMOZURU, Michito; TSUBOTA, Toshio

    2016-01-01

    We compared cortisol and thyroid hormone (T3 and T4) concentrations between tuberculosis (TB)-suspected (n=10) and healthy (n=10) elephants of Nepal. Whole blood was collected from captive elephants throughout Nepal, and TB testing was performed using the ElephantTB STAT-PAK® and DPP VetTB® serological assays that detect antibodies against Mycobacterium tuberculosis and M. bovis in elephant serum. Cortisol, T3 and T4 were quantified by competitive enzyme immunoassays, and the results showed no significant differences in hormone concentrations between TB-suspect and healthy elephants. These preliminary data suggest neither adrenal nor thyroid function is altered by TB disease status. However, more elephants, including those positively diagnosed for TB by trunk wash cultures, need to be evaluated over time to confirm results. PMID:27452878

  4. Cost-benefit analysis of Xpert MTB/RIF for tuberculosis suspects in German hospitals.

    PubMed

    Diel, Roland; Nienhaus, Albert; Hillemann, Doris; Richter, Elvira

    2016-02-01

    Our objective was to assess the cost-benefit of enhancing or replacing the conventional sputum smear with the real-time PCR Xpert MTB/RIF method in the inpatient diagnostic schema for tuberculosis (TB).Recent data from published per-case cost studies for TB/multidrug-resistant (MDR)-TB and from comparative analyses of sputum microscopy, mycobacterial culture, Xpert MTB/RIF and drug susceptibility testing, performed at the German National Reference Center for Mycobacteria, were used. Potential cost savings of Xpert MTB/RIF, based on test accuracy and multiple cost drivers, were calculated for diagnosing TB/MDR-TB suspects from the hospital perspective.Implementing Xpert MTB/RIF as an add-on in smear-positive and smear-negative TB suspects saves on average €48.72 and €503, respectively, per admitted patient as compared with the conventional approach. In smear-positive and smear-negative MDR-TB suspects, cost savings amount to €189.56 and €515.25 per person, respectively. Full replacement of microscopy by Xpert MTB/RIF saves €449.98. In probabilistic Monte-Carlo simulation, adding Xpert MTB/RIF is less costly in 46.4% and 76.2% of smear-positive TB and MDR-TB suspects, respectively, but 100% less expensive in all smear-negative suspects. Full replacement by Xpert MTB/RIF is also consistently cost-saving.Using Xpert MTB/RIF as an add-on to and even as a replacement for sputum smear examination may significantly reduce expenditures in TB suspects.

  5. Factors influencing polymerase chain reaction outcomes in patients with clinically suspected ocular tuberculosis

    PubMed Central

    2014-01-01

    Background Polymerase chain reaction (PCR) assay can be a useful method for definitive diagnosis in paucibacillary infections such as ocular tuberculosis (TB). In this study, we have evaluated factors affecting PCR outcomes in patients with clinically suspected ocular TB. Patients with clinically suspected ocular TB were investigated by PCR of aqueous or vitreous samples. Three control groups were also tested: group 1 included culture-proven non-tuberculous endophthalmitis, group 2 culture-negative non-tuberculous endophthalmitis, and group 3 patients undergoing surgery for uncomplicated cataract. PCR targeted one or more of following targets: IS6110, MPB64, and protein b genes of Mycobacterium tuberculosis complex. Multiple regression analysis (5% level of significance) was done to evaluate the associations between positive PCR outcome and laterality of disease, tuberculin skin test (TST)/interferon-gamma release assay (IGRA), chest radiography, and type of sample (aqueous or vitreous). The main outcome measures were positive PCR by one or more gene targets, and factors influencing positive PCR outcomes. Results All 114 samples were tested for MPB64, 110 for protein b, and 88 for IS6110. MPB64 was positive in 70.2% (n = 80) of tested samples, protein b in 40.0% (n = 44), and IS6110 in only 9.1% (n = 8). DNA sequencing of amplicons from four randomly chosen PCR reactions showed homology for M. tuberculosis complex. Of the 80 PCR-positive patients, 71 completed a full course of antitubercular therapy, of which 65 patients (91.5%) had complete resolution of inflammation at final follow-up. Among controls, 12.5% (3 out of 24) in group 1 and 18.7% (6 out of 32) in group 2 also tested positive by PCR. No PCR-positive outcome was observed in control group 3 (n = 25). Multiple regression analysis revealed significant association of positive PCR outcome with bilateral presentation, but not with a positive TST/IGRA, chest radiography, or type of sample

  6. Suspected pulmonary tuberculosis exposure at a remote U.S. army camp in northeastern Afghanistan, 2007.

    PubMed

    Nevin, Remington L; Silvestri, John W; Hu, Zheng; Tobler, Steven K; Trotta, Richard F

    2008-07-01

    Military personnel serving at remote camps in the border regions of northeastern Afghanistan may experience crowded living conditions and may have frequent interaction with local national (LN) workers, increasing the risk of exposure to multiple endemic diseases including tuberculosis (TB). In January 2007, pulmonary TB was clinically suspected in a LN worker who had close contact with a company of 92 U.S. Army personnel at a remote camp in Konar province, Afghanistan, over 4 months. This report describes the results of the contact investigation conducted by the U.S. Army, in which four U.S. personnel were found to have evidence of TB exposure. This investigation raises concerns arising from the high prevalence of drug-resistant TB in the region and in neighboring North West Frontier Province, Pakistan, and demonstrates the challenges of conducting contact investigations and using LN workers in deployed wartime environments.

  7. Knowledge, Health Seeking Behavior and Perceived Stigma towards Tuberculosis among Tuberculosis Suspects in a Rural Community in Southwest Ethiopia

    PubMed Central

    Abebe, Gemeda; Deribew, Amare; Apers, Ludwig; Woldemichael, Kifle; Shiffa, Jaffer; Tesfaye, Markos; Abdissa, Alemseged; Deribie, Fetene; Jira, Chali; Bezabih, Mesele; Aseffa, Abraham; Duchateau, Luc; Colebunders, Robert

    2010-01-01

    Background Perceived stigma and lack of awareness could contribute to the late presentation and low detection rate of tuberculosis (TB). We conducted a study in rural southwest Ethiopia among TB suspects to assess knowledge about and stigma towards TB and their health seeking behavior. Methods A community based cross sectional survey was conducted from February to March 2009 in the Gilgel Gibe field research area. Any person 15 years and above with cough for at least 2 weeks was considered a TB suspect and included in the study. Data were collected by trained personnel using a pretested structured questionnaire. Logistic regression analysis was done using SPSS 15.0 statistical software. Results Of the 476 pulmonary TB suspects, 395 (83.0%) had ever heard of TB; “evil eye” (50.4%) was the commonly mentioned cause of TB. Individuals who could read and write were more likely to be aware about TB [(crude OR = 2.98, (95%CI: 1.25, 7.08)] and more likely to know that TB is caused by a microorganism [(adjusted OR = 3.16, (95%CI: 1.77, 5.65)] than non-educated individuals. Males were more likely to know the cause of TB [(adjusted OR = 1.92, (95%CI: 1.22, 3.03)] than females. 51.3% of TB suspects perceived that other people would consider them inferior if they had TB. High stigma towards TB was reported by 199(51.2%). 220 (46.2%) did not seek help for their illness. Individuals who had previous anti-TB treatment were more likely to have appropriate health seeking behavior [(adjusted OR = 3.65, (95%CI: 1.89, 7.06)] than those who had not. Conclusion There was little knowledge about TB in the Gilgel Gibe field research area. We observed inappropriate health seeking behavior and stigma towards TB. TB control programs in Ethiopia should educate rural communities, particularly females and non-educated individuals, about the cause and the importance of early diagnosis and treatment of TB. PMID:20948963

  8. Detection and Quantification of Mycobacterium tuberculosis in the Sputum of Culture-Negative HIV-infected Pulmonary Tuberculosis Suspects: A Proof-of-Concept Study

    PubMed Central

    Madico, Guillermo; Mpeirwe, Moses; White, Laura; Vinhas, Solange; Orr, Beverley; Orikiriza, Patrick; Miller, Nancy S.; Gaeddert, Mary; Mwanga-Amumpaire, Juliet; Palaci, Moises; Kreiswirth, Barry; Straight, Joe; Dietze, Reynaldo; Boum, Yap; Jones-López, Edward C.

    2016-01-01

    Rationale Rapid diagnosis of pulmonary tuberculosis (TB) is critical for timely initiation of treatment and interruption of transmission. Yet, despite recent advances, many patients remain undiagnosed. Culture, usually considered the most sensitive diagnostic method, is sub-optimal for paucibacillary disease. Methods We evaluated the Totally Optimized PCR (TOP) TB assay, a new molecular test that we hypothesize is more sensitive than culture. After pre-clinical studies, we estimated TOP’s per-patient sensitivity and specificity in a convenience sample of 261 HIV-infected pulmonary TB suspects enrolled into a TB diagnostic study in Mbarara, Uganda against MGIT culture, Xpert MTB/RIF and a composite reference standard. We validated results with a confirmatory PCR used for sequencing M. tuberculosis. Measurements and Results Using culture as reference, TOP had 100% sensitivity but 35% specificity. Against a composite reference standard, the sensitivity of culture (27%) and Xpert MTB/RIF (27%) was lower than TOP (99%), with similar specificity (100%, 98% and 87%, respectively). In unadjusted analyses, culture-negative/TOP-positive patients were more likely to be older (P<0·001), female (P<0·001), have salivary sputum (P = 0·05), sputum smear-negative (P<0.001) and less advanced disease on chest radiograph (P = 0.05). M. tuberculosis genotypes identified in sputum by DNA sequencing exhibit differential growth in culture. Conclusions These findings suggest that the TOP TB assay is accurately detecting M. tuberculosis DNA in the sputum of culture-negative tuberculosis suspects. Our results require prospective validation with clinical outcomes. If the operating characteristics of the TOP assay are confirmed in future studies, it will be justified as a “TB rule out” test. PMID:27391604

  9. HIV Infection Is Associated with Shortened Telomere Length in Ugandans with Suspected Tuberculosis

    PubMed Central

    Auld, Elizabeth; Lin, Jue; Chang, Emily; Byanyima, Patrick; Ayakaka, Irene; Musisi, Emmanuel; Worodria, William; Davis, J. Lucian; Segal, Mark; Blackburn, Elizabeth; Huang, Laurence

    2016-01-01

    Introduction HIV infection is a risk factor for opportunistic pneumonias such as tuberculosis (TB) and for age-associated health complications. Short telomeres, markers of biological aging, are also associated with an increased risk of age-associated diseases and mortality. Our goals were to use a single cohort of HIV-infected and HIV-uninfected individuals hospitalized with pneumonia to assess whether shortened telomere length was associated with HIV infection, TB diagnosis, and 2-month mortality. Methods This was a sub-study of the IHOP Study, a prospective observational study. Participants consisted of 184 adults admitted to Mulago Hospital in Kampala, Uganda who underwent evaluation for suspected TB and were followed for 2 months. Standardized questionnaires were administered to collect demographic and clinical data. PBMCs were isolated and analyzed using quantitative PCR to determine telomere length. The association between HIV infection, demographic and clinical characteristics, and telomere length was assessed, as were the associations between telomere length, TB diagnosis and 2-month mortality. Variables with a P≤0.2 in bivariate analysis were included in multivariate models. Results No significant demographic or clinical differences were observed between the HIV-infected and HIV-uninfected subjects. Older age (P<0.0001), male gender (P = 0.04), total pack-years smoked (P<0.001), alcohol consumption in the past year (P = 0.12), and asthma (P = 0.08) were all associated (P≤0.2) with shorter telomere length in bivariate analysis. In multivariate analysis adjusting for these five variables, HIV-positive participants had significantly shorter telomeres than HIV-negative participants (β = -0.0621, 95% CI -0.113 to -0.011, P = 0.02). Shortened telomeres were not associated with TB or short-term mortality. Conclusions The association between HIV infection and shorter telomeres suggests that HIV may play a role in cellular senescence and biological aging and

  10. Mycobacterium tuberculosis prevents inflammasome activation.

    PubMed

    Master, Sharon S; Rampini, Silvana K; Davis, Alexander S; Keller, Christine; Ehlers, Stefan; Springer, Burkhard; Timmins, Graham S; Sander, Peter; Deretic, Vojo

    2008-04-17

    Mycobacterium tuberculosis (Mtb) parasitizes host macrophages and subverts host innate and adaptive immunity. Several cytokines elicited by Mtb are mediators of mycobacterial clearance or are involved in tuberculosis pathology. Surprisingly, interleukin-1beta (IL-1beta), a major proinflammatory cytokine, has not been implicated in host-Mtb interactions. IL-1beta is activated by processing upon assembly of the inflammasome, a specialized inflammatory caspase-activating protein complex. Here, we show that Mtb prevents inflammasome activation and IL-1beta processing. An Mtb gene, zmp1, which encodes a putative Zn(2+) metalloprotease, is required for this process. Infection of macrophages with zmp1-deleted Mtb triggered activation of the inflammasome, resulting in increased IL-1beta secretion, enhanced maturation of Mtb containing phagosomes, improved mycobacterial clearance by macrophages, and lower bacterial burden in the lungs of aerosol-infected mice. Thus, we uncovered a previously masked role for IL-1beta in the control of Mtb and a mycobacterial system that prevents inflammasome and, therefore, IL-1beta activation.

  11. Operational Implementation of LED Fluorescence Microscopy in Screening Tuberculosis Suspects in an Urban HIV Clinic in Uganda

    PubMed Central

    Albert, Heidi; Nakiyingi, Lydia; Sempa, Joseph; Mbabazi, Olive; Mukkada, Sheena; Nyesiga, Barnabas; Perkins, Mark D.; Manabe, Yukari C.

    2013-01-01

    Background Light emitting diode (LED) fluorescence microscopy (FM) is an affordable, technology targeted for use in resource-limited settings and recommended for widespread roll-out by the World Health Organization (WHO). We sought to compare the operational performance of three LED FM methods compared to light microscopy in a cohort of HIV-positive tuberculosis (TB) suspects at an urban clinic in a high TB burden country. Methods Two spot specimens collected from TB suspects were included in the study. Smears were stained using auramine O method and read after blinding by three LED-based FM methods by trained laboratory technicians in the Infectious Diseases Institutelaboratory. Leftover portions of the refrigerated sputum specimens were transported to the FIND Tuberculosis Research Laboratory for Ziehl Neelsen (ZN) smear preparation and reading by experienced technologist as well as liquid and solid culture. Results 174 of 627 (27.8%) specimens collected yielded one or more positive mycobacterial cultures. 94.3% (164/174) were M. tuberculosis complex. LED FM was between 7.3–11.0% more sensitive compared to ZN microscopy. Of the 592 specimens examined by all microscopy methods, there was no significant difference in sensitivity between the three LED FM methods. The specificity of the LED FM methods was between 6.1% and 7.7% lower than ZN microscopy (P<0.001), although exclusion of the single poor reader resulted in over 98% specificity for all FM methods. Conclusions Laboratory technicians in routine settings can be trained to use FM which is more sensitive than ZN microscopy. Despite rigorous proficiency testing, there were operator-dependent accuracy issues which highlight the critical need for intensive quality assurance procedures during LED FM implementation. The low sensitivity of FM for HIV-positive individuals particularly those with low CD4 T cell counts, will limit the number of additional patients found by LED FM in countries with high rates of HIV co

  12. Prevalence of melioidosis in patients with suspected pulmonary tuberculosis and sputum smear negative for acid-fast bacilli in northeast Thailand.

    PubMed

    Suntornsut, Pornpan; Kasemsupat, Kriangsak; Silairatana, Santi; Wongsuvan, Gumphol; Jutrakul, Yaowaruk; Wuthiekanun, Vanaporn; Day, Nicholas P J; Peacock, Sharon J; Limmathurotsakul, Direk

    2013-11-01

    The clinical and radiological features of pulmonary melioidosis can mimic tuberculosis. We prospectively evaluated 118 patients with suspected pulmonary tuberculosis who were acid-fast bacilli (AFB) smear negative at Udon Thani Hospital, northeast Thailand. Culture of residual sputum from AFB testing was positive for Burkholderia pseudomallei in three patients (2.5%; 95% confidence interval [CI] 0.5-7.3%). We propose that in melioidosis-endemic areas, residual sputum from AFB testing should be routinely cultured for B. pseudomallei.

  13. Validation of Mycobacterium tuberculosis Rv1681 Protein as a Diagnostic Marker of Active Pulmonary Tuberculosis

    PubMed Central

    Macovei, Lilia; Kanunfre, Kelly; Dhiman, Rakesh; Restrepo, Blanca I.; Zarate, Izelda; Pino, Paula A.; Mora-Guzman, Francisco; Fujiwara, Ricardo T.; Michel, Gerd; Kashino, Suely S.

    2013-01-01

    The development of an accurate antigen detection assay for the diagnosis of active tuberculosis (TB) would represent a major clinical advance. Here, we demonstrate that the Mycobacterium tuberculosis Rv1681 protein is a biomarker for active TB with potential diagnostic utility. We initially identified, by mass spectroscopy, peptides from the Rv1681 protein in urine specimens from 4 patients with untreated active TB. Rabbit IgG anti-recombinant Rv1681 detected Rv1681 protein in lysates and culture filtrates of M. tuberculosis and immunoprecipitated it from pooled urine specimens from two TB patients. An enzyme-linked immunosorbent assay formatted with these antibodies detected Rv1681 protein in unconcentrated urine specimens from 11/25 (44%) TB patients and 1/21 (4.8%) subjects in whom TB was initially clinically suspected but then ruled out by conventional methods. Rv1681 protein was not detected in urine specimens from 10 subjects with Escherichia coli-positive urine cultures, 26 subjects with confirmed non-TB tropical diseases (11 with schistosomiasis, 5 with Chagas' disease, and 10 with cutaneous leishmaniasis), and 14 healthy subjects. These results provide strong validation of Rv1681 protein as a promising biomarker for TB diagnosis. PMID:23390284

  14. Validation of a Clinical-Radiographic Score to Assess the Probability of Pulmonary Tuberculosis in Suspect Patients with Negative Sputum Smears

    PubMed Central

    Soto, Alonso; Solari, Lely; Díaz, Javier; Mantilla, Alberto; Matthys, Francine; van der Stuyft, Patrick

    2011-01-01

    Background Clinical suspects of pulmonary tuberculosis in which the sputum smears are negative for acid fast bacilli represent a diagnostic challenge in resource constrained settings. Our objective was to validate an existing clinical-radiographic score that assessed the probability of smear-negative pulmonary tuberculosis (SNPT) in high incidence settings in Peru. Methodology/Principal Findings We included in two referral hospitals in Lima patients with clinical suspicion of pulmonary tuberculosis and two or more negative sputum smears. Using a published but not externally validated score, patients were classified as having low, intermediate or high probability of pulmonary tuberculosis. The reference standard for the diagnosis of tuberculosis was a positive sputum culture in at least one of 2 liquid (MGIT or Middlebrook 7H9) and 1 solid (Ogawa) media. Prevalence of tuberculosis was calculated in each of the three probability groups. 684 patients were included. 184 (27.8%) had a diagnosis of pulmonary tuberculosis. The score did not perform well in patients with a previous history of pulmonary tuberculosis. In patients without, the prevalence of tuberculosis was 5.1%, 31.7% and 72% in the low, intermediate and high probability group respectively. The area under de ROC curve was 0.76 (95% CI 0.72–0.80) and scores ≥6 had a positive LR of 10.9. Conclusions/Significance In smear negative suspects without previous history of tuberculosis, the clinical-radiographic score can be used as a tool to assess the probability of pulmonary tuberculosis and to guide the decision to initiate or defer treatment or to requesting additional tests. PMID:21483690

  15. [Management of TB suspected cases of drug resistant tuberculosis requiring a second treatment].

    PubMed

    Caminero, José A

    2004-06-01

    The management of patients with resistance to anti tuberculous drugs is complex and therefore must be managed by physician specialists. The most difficult patients are the cases in retreatment, where some very different possibilities are possible, as abandonment, failures and relapses. Patients with multi-drug resistant (MDR) tuberculosis are the most difficult to treat; MDR appears in all the failures or non-adherences to the treatment regime. To elaborate a scheme of retreatment for these patients, two guidelines must be followed: (1) do not rely on outcomes of drug susceptibility tests and (2) a detailed history of drug treatment must be considered of paramount importance. With this information, a retreatment scheme can be formulated that involves the use of at least three drugs not previously taken by the patient. For a successful control of tuberculosis, the national tuberculosis programs in Latin American countries must assure careful management of newly diagnosed patients. Secondly, if resources are available, a bank of second-line drugs must be ready for managing retreatment situations (e.g., 3 Z-Kn-Eth-Of/15 Z-Eth-Of) if first line drug treatments fail. Using individualized retreatment with second line drugs is recommended only in industrialized countries, and for a few middle income countries as a last resort.

  16. Prevalence of Non-Tuberculosis Mycobacterial Infections among Tuberculosis Suspects in Iran: Systematic Review and Meta-Analysis

    PubMed Central

    Nasiri, Mohammad Javad; Dabiri, Hossein; Darban-Sarokhalil, Davood; Hashemi Shahraki, Abdolrazagh

    2015-01-01

    Introduction The infections due to Non-Tuberculosis Mycobacteria (NTM) are becoming an important health problem in many countries in the world. Globally, an increase in NTM infections has been reported from many countries around the world. However, limited information is available about the prevalence of NTM infections in Iran. Material and Methods The data of the prevalence of NTM infections were collected from databases such as PubMed, Web of science, Cochrane Library, Embase, Scopus, Iranmedex, and Scientific Information Database. Comprehensive Meta-Analysis (V2.0, Biostat) software was used to analyze the data. Results The meta-analyses showed that the prevalence of NTM infections was 10.2% (95% confidence interval [95% CI] 6.3-15.9) among culture-positive cases of tuberculosis (TB) in Iran. The further stratified analyses indicated that the prevalence of NTM was higher in studies that were done after year 2000. Additionally, M. simiae (43.3% [95% CI 36.8-50.0]), M. intracellucar (27.3% [95% CI 0.7-95.5]) and M. fortuitum (22.7% [95% CI 16.1-30.9]) were the most prevalent NTM species, respectively. Discussion The relatively high prevalence of NTM infections (10.2%) among culture positive cases for TB underlines the need for greater enforcement of infection control strategies. Establishment of appropriate diagnostic criteria and management guidelines for NTM diseases and expanding the number and quality of regional reference laboratories may facilitate more accurate action for prevention and control of NTM infections in Iran. PMID:26052701

  17. Identification of Mycobacterium tuberculosis in Clinical Specimens of Patients Suspected of Having Extrapulmonary Tuberculosis by Application of Nested PCR on Five Different Genes.

    PubMed

    Khosravi, Azar D; Alami, Ameneh; Meghdadi, Hossein; Hosseini, Atta A

    2017-01-01

    Definitive and rapid diagnosis of extrapulmonary tuberculosis (EPTB) is challenging since conventional techniques have limitations due to the paucibacillary nature of the disease. To increase the sensitivity of detection of Mycobacterium tuberculosis (MTB) in EPTB specimens, we performed a nested PCR assay targeting several genes of MTB on EPTB specimens. A total of 100 clinical specimens from suspected cases of EPTB were processed. Standard staining for acid fast bacilli (AFB) was performed as the preliminary screening test. Extracted DNAs from specimens were subjected to Nested PCR technique for the detection of five different MTB target genes of IS6110, IS1081, hsp65kd, mbp64, and mtp40. On performing AFB staining, only 13% of specimens were positive, of which ascites fluid (33.3%), followed by pleural effusion (30.8%) showed the greatest AFB positivity rate. We demonstrated slight improvement in yields in lymph node which comprised the majority of specimens in this study, by employing PCR targeted to IS6110- and hsp65-genes in comparison to AFB staining. However, the yields in ascites fluid and pleural effusion were not substantially improved by PCR, but those from bone and wound were, as in nested PCR employing either gene, the same positivity rate were obtained for ascites fluid (33.3%), while for pleural effusion specimens only IS1081 based PCR showed identical positivity rate with AFB stain (30.8%). The results for bone and wound specimens, however, demonstrated an improved yield mainly by employing IS1081 gene. Here, we report higher detection rate of EPTB in clinical specimens using five different targeted MTB genes. This nested PCR approach facilitates the comparison and the selection of the most frequently detected genes. Of course this study demonstrated the priority of IS1081 followed by mtp40 and IS6110, among the five tested genes and indicates the effectiveness of any of the three genes in the design of an efficient nested-PCR test that facilitates

  18. Identification of Mycobacterium tuberculosis in Clinical Specimens of Patients Suspected of Having Extrapulmonary Tuberculosis by Application of Nested PCR on Five Different Genes

    PubMed Central

    Khosravi, Azar D.; Alami, Ameneh; Meghdadi, Hossein; Hosseini, Atta A.

    2017-01-01

    Definitive and rapid diagnosis of extrapulmonary tuberculosis (EPTB) is challenging since conventional techniques have limitations due to the paucibacillary nature of the disease. To increase the sensitivity of detection of Mycobacterium tuberculosis (MTB) in EPTB specimens, we performed a nested PCR assay targeting several genes of MTB on EPTB specimens. A total of 100 clinical specimens from suspected cases of EPTB were processed. Standard staining for acid fast bacilli (AFB) was performed as the preliminary screening test. Extracted DNAs from specimens were subjected to Nested PCR technique for the detection of five different MTB target genes of IS6110, IS1081, hsp65kd, mbp64, and mtp40. On performing AFB staining, only 13% of specimens were positive, of which ascites fluid (33.3%), followed by pleural effusion (30.8%) showed the greatest AFB positivity rate. We demonstrated slight improvement in yields in lymph node which comprised the majority of specimens in this study, by employing PCR targeted to IS6110- and hsp65-genes in comparison to AFB staining. However, the yields in ascites fluid and pleural effusion were not substantially improved by PCR, but those from bone and wound were, as in nested PCR employing either gene, the same positivity rate were obtained for ascites fluid (33.3%), while for pleural effusion specimens only IS1081 based PCR showed identical positivity rate with AFB stain (30.8%). The results for bone and wound specimens, however, demonstrated an improved yield mainly by employing IS1081 gene. Here, we report higher detection rate of EPTB in clinical specimens using five different targeted MTB genes. This nested PCR approach facilitates the comparison and the selection of the most frequently detected genes. Of course this study demonstrated the priority of IS1081 followed by mtp40 and IS6110, among the five tested genes and indicates the effectiveness of any of the three genes in the design of an efficient nested-PCR test that facilitates

  19. T-Cell Immunophenotyping Distinguishes Active From Latent Tuberculosis

    PubMed Central

    Pollock, Katrina M.; Whitworth, Hilary S.; Montamat-Sicotte, Damien J.; Grass, Lisa; Cooke, Graham S.; Kapembwa, Moses S.; Kon, Onn M.; Sampson, Robert D.; Taylor, Graham P.; Lalvani, Ajit

    2013-01-01

    Background. Changes in the phenotype and function of Mycobacterium tuberculosis (M. tuberculosis)-specific CD4+ and CD8+ T-cell subsets in response to stage of infection may allow discrimination between active tuberculosis and latent tuberculosis infection. Methods. A prospective comparison of M. tuberculosis-specific cellular immunity in subjects with active tuberculosis and latent tuberculosis infection, with and without human immunodeficiency virus (HIV) coinfection. Polychromatic flow cytometry was used to measure CD4+ and CD8+ T-cell subset phenotype and secretion of interferon γ (IFN-γ), interleukin 2 (IL-2), and tumor necrosis factor α (TNF-α). Results. Frequencies of CD4+ and CD8+ cells secreting IFN-γ-only, TNF-α-only and dual IFN-γ/TNF-α were greater in active tuberculosis vs latent tuberculosis infection. All M. tuberculosis-specific CD4+ subsets, with the exception of IL-2-only cells, switched from central to effector memory phenotype in active tuberculosis vs latent tuberculosis infection, accompanied by a reduction in IL-7 receptor α (CD127) expression. The frequency of PPD-specific CD4+ TNF-α-only-secreting T cells with an effector phenotype accurately distinguished active tuberculosis from latent tuberculosis infection with an area under the curve of 0.99, substantially more discriminatory than measurement of function alone. Conclusions. Combined measurement of T-cell phenotype and function defines a highly discriminatory biomarker of tuberculosis disease activity. Unlocking the diagnostic and monitoring potential of this combined approach now requires validation in large-scale prospective studies. PMID:23966657

  20. Progressive intraparenchymal lung nodules dissemination in a heavy smoker and seropositive rheumatoid arthritis suspected of tuberculosis relapse.

    PubMed

    Arghir, Oana Cristina; Niţu, Mimi; Trenchea, Mihaela; Ciobotaru, Camelia

    2013-01-01

    Anthony Caplan first described rheumatoid lung nodules associated with pneumoconiosis in coal-miners (Caplan, 1953). Intraparenchymal lung nodules were later described in rheumatoid arthritis (RA) patients who were never exposed to coal dust and/or without pneumoconiosis. Rheumatoid lung nodules are usually detected in unselected patients: 0.2% in chest radiography and 4% in high-resolution computed tomography (Nannini et al., 2008). Patients could be reluctant to perform surgical lung biopsy for an accurate histopathological diagnosis. We present a peculiar association between a seropositive RA and a presumptive active tuberculosis (TB) disease in a 59-year-old male patient, ex-smoker with a previously healed pulmonary TB disease. The purpose of this report is to describe an unusual case of a presumptive relapse of the nodular TB disease, which progressed to an extensive nodular bilateral dissemination under anti-tuberculosis therapy, mimicking a metastatic carcinoma. The diagnosis of rheumatoid necrobiotic lung nodules was confirmed after open biopsy left pulmonary was performed. Formalin-fixed paraffin-embedded pulmonary rheumatoid nodules were processed for histology and stained with Masson's trichrome. Central structure of the removed pulmonary nodules is typical of a rheumatoid nodule with central necrosis surrounded by a palisade of macrophages. The accumulation of anthracotic pigment was noticed inside the pulmonary nodules in a RA patient without professional exposure to coal or mineral dust. This rare entity is an appearance of the rheumatoid nodules lung syndrome and anthracosis in a heavy tobacco former smoker.

  1. Evaluation of the efficiency of nested q-PCR in the detection of Mycobacterium tuberculosis complex directly from tuberculosis-suspected lesions in post-mortem macroscopic inspections of bovine carcasses slaughtered in the state of Mato Grosso, Brazil.

    PubMed

    Carvalho, Ricardo César Tavares; Furlanetto, Leone Vinícius; Maruyama, Fernanda Harumy; Araújo, Cristina Pires de; Barros, Sílvia Letícia Bomfim; Ramos, Carlos Alberto do Nascimento; Dutra, Valéria; Araújo, Flábio Ribeiro de; Paschoalin, Vânia Margaret Flosi; Nakazato, Luciano; Figueiredo, Eduardo Eustáquio de Souza

    2015-08-01

    Bovine tuberculosis (BTB) is a zoonotic disease caused by Mycobacterium bovis, a member of the Mycobacterium tuberculosis complex (MTC). The quick and specific detection of this species is of extreme importance, since BTB may cause economic impacts, in addition to presenting imminent risks to human health. In the present study a nested real-time PCR test (nested q-PCR) was used in post-mortem evaluations to assess cattle carcasses with BTB-suspected lesions. A total of 41,193 cattle slaughtered in slaughterhouses located in the state of Mato Grosso, were examined. Of the examined animals, 198 (0.48%) showed BTB-suspected lesions. M. bovis was isolated in 1.5% (3/198) of the samples. Multiplex-PCR detected MTC in 7% (14/198) of the samples. The nested q-PCR test detected MTC in 28% (56/198) of the BTB-suspected lesions, demonstrating higher efficiency when compared to the multiplex-PCR and conventional microbiology. Nested q-PCR can therefore be used as a complementary test in the national program for control and eradication of bovine tuberculosis.

  2. [Spontaneous pneumothorax associated to active pulmonary tuberculosis].

    PubMed

    Díaz Rojas, F; Córdova Gutiérrez, H; Aguirre Gas, H

    1978-01-01

    This paper reviewed 8 cases of spontaneous pneumothorax, associated to pulmonary tuberculosis during a period of time of two years at the A.L.M. General Hospital of Toluca, Mex. The diagnosis was confirmed by clinical picture, radiology and bacteriology studies. Six males and two females proceding of the low class; farmers all of them. Their age ranged between 18 and 35 years. Two of the patients showed cavitary lesions, five had difusse fibrosis of the lung. We analized the clinical manifestations and reviewed the pathogenic mechanisms as well the medical and surgical treatment. No deaths ocurred en this series. We concluded that the direct relation between active pulmonary tuberculosis and spontaneous pneumothorax is not clear, but their association in this serie suggested further studies to stablished this. We emphasized the importance of this complication rare in the world literature.

  3. Direct molecular detection of Mycobacterium tuberculosis suspected to be the specific infection in a case of recurrent tonsillitis.

    PubMed

    Lukšić, Boris; Kljajić, Zlatko; Roje, Zeljka; Forempoher, Gea; Grgić, Duška; Janković-Katalinić, Vera; Goić-Barišić, Ivana

    2013-12-01

    We report a case of a 21-year-old man with recurrent tonsillitis caused by Mycobacterium tuberculosis. For a period of 5 months, the patient had tonsillitis seven times and was treated with several oral or parenteral antibiotics. On one of these occasions, tonsillitis was complicated with a peritonsillar abscess that was treated by incision. According to relevant bibliographic data, this is the first case of Mycobacterium tuberculosis confirmed by direct molecular microbiology methods from the tonsillar tissue of a young immunocompetent male reported in Europe. In a case of recurrent tonsillitis, Mycobacterium tuberculosis infection should be considered as a possible cause.

  4. Sequence Analysis of Fluoroquinolone Resistance-Associated Genes gyrA and gyrB in Clinical Mycobacterium tuberculosis Isolates from Patients Suspected of Having Multidrug-Resistant Tuberculosis in New Delhi, India

    PubMed Central

    Singhal, Ritu; Reynolds, Paul R.; Marola, Jamie L.; Epperson, L. Elaine; Arora, Jyoti; Sarin, Rohit; Strong, Michael

    2016-01-01

    Fluoroquinolones (FQs) are broad-spectrum antibiotics recommended for the treatment of multidrug-resistant tuberculosis (MDR-TB) patients. FQ resistance, caused by mutations in the gyrA and gyrB genes of Mycobacterium tuberculosis, is increasingly reported worldwide; however, information on mutations occurring in strains from the Indian subcontinent is scarce. Hence, in this study, we aimed to characterize mutations in the gyrA and gyrB genes of acid-fast bacillus (AFB) smear-positive sediments or of M. tuberculosis isolates from AFB smear-negative samples from patients in India suspected of having MDR-TB. A total of 152 samples from patients suspected of having MDR-TB were included in the study. One hundred forty-six strains detected in these samples were characterized by sequencing of the gyrA and gyrB genes. The extracted DNA was subjected to successive amplifications using a nested PCR protocol, followed by sequencing. A total of 27 mutations were observed in the gyrA genes of 25 strains, while no mutations were observed in the gyrB genes. The most common mutations occurred at amino acid position 94 (13/27 [48.1%]); of these, the D94G mutation was the most prevalent. The gyrA mutations were significantly associated with patients with rifampin (RIF)-resistant TB. Heterozygosity was seen in 4/27 (14.8%) mutations, suggesting the occurrence of mixed populations with different antimicrobial susceptibilities. A high rate of FQ-resistant mutations (17.1%) was obtained among the isolates of TB patients suspected of having MDR-TB. These observations emphasize the need for accurate and rapid molecular tests for the detection of FQ-resistant mutations at the time of MDR-TB diagnosis. PMID:27335153

  5. Tuberculosis

    MedlinePlus

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Tuberculosis KidsHealth > For Teens > Tuberculosis A A A What's in this article? TB ... Duration When to Call the Doctor en español Tuberculosis TB Basics Tuberculosis (also known as "TB") is ...

  6. Tuberculosis

    MedlinePlus

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Tuberculosis KidsHealth > For Teens > Tuberculosis Print A A A What's in this article? ... Duration When to Call the Doctor en español Tuberculosis TB Basics Tuberculosis (also known as "TB") is ...

  7. Clinical value of whole-blood interferon-gamma assay in patients with suspected pulmonary tuberculosis and AFB smear- and polymerase chain reaction-negative bronchial aspirates.

    PubMed

    Lee, Jaehee; Lee, Shin Yup; Yoo, Seung Soo; Cha, Seung Ick; Won, Dong Il; Park, Jae Yong; Lee, Won-Kil; Kim, Chang Ho

    2012-07-01

    Combining a polymerase chain reaction (PCR) test with bronchoscopy is frequently performed to allow a rapid diagnosis of smear-negative pulmonary tuberculosis (PTB). However, limited data are available concerning clinical judgment in patients with suspected PTB and AFB smear- and PCR-negative bronchial aspirates (BA). The present study evaluated the usefulness of whole-blood QuantiFERON-TB Gold In-Tube (QFT) testing in these patients. Of 166 patients with suspected PTB who had undergone bronchoscopy because of smear-negative sputum or inadequate sputum production, 93 (56%) were diagnosed with culture-positive PTB. Seventy-four patients were either AFB smear- or PCR-positive. In the 75 patients whose BA AFB smear and PCR results were both negative, 19 were finally diagnosed with PTB by culture. The QFT test had a negative predictive value of 91% for PTB. The QFT test may be useful for excluding PTB in patients with suspected PTB whose BA AFB smear and PCR results are both negative.

  8. Prevalence of tuberculosis, HIV, and TB-HIV co-infection among pulmonary tuberculosis suspects in a predominantly pastoralist area, northeast Ethiopia

    PubMed Central

    Belay, Mulugeta; Bjune, Gunnar; Abebe, Fekadu

    2015-01-01

    Background TB-HIV co-infection is one of the biggest public health challenges in sub-Saharan Africa. Although there is a wealth of information on TB-HIV co-infection among settled populations in Africa and elsewhere, to our knowledge, there are no published reports on TB-HIV co-infection from pastoral communities. In this study, we report the prevalence of TB, HIV and TB-HIV co-infection among pulmonary TB suspects in the Afar Regional State of Ethiopia. Design In a cross-sectional study design, 325 pulmonary TB suspects were included from five health facilities. Three sputum samples (spot-morning-spot) were collected from each participant. Sputum samples were examined for the presence of acid fast bacilli using Ziehl–Neelsen staining method, and culture was done on the remaining sputum samples. Participants were interviewed and HIV tested. Results Of the 325 pulmonary TB suspects, 44 (13.5%) were smear positive, and 105 (32.3%) were culture positive. Among smear-positive patients, five were culture negative and, therefore, a total of 110 (33.8%) suspects were bacteriologically confirmed pulmonary TB patients. Out of 287 pulmonary TB suspects who were tested for HIV infection, 82 (28.6%) were HIV positive. A significantly higher proportion of bacteriologically confirmed pulmonary TB patients [40 (40.4%)] were HIV co-infected compared with patients without bacteriological evidence for pulmonary TB [42 (22.3%)]. However, among ethnic Afar pastoralists, HIV infections in smear- and/or culture-negative pulmonary TB suspects [7 (7.6%)] and bacteriologically confirmed pulmonary TB patients [4 (11.8%)] were comparable. On multivariable logistic regression analysis, Afar ethnicity was independently associated with low HIV infection [OR=0.16 (95% CI: 0.07–0.37)], whereas literacy was independently associated with higher HIV infection [OR=2.21 (95% CI: 1.05–4.64)]. Conclusions Although the overall prevalence of TB-HIV co-infection in the current study is high, ethnic

  9. Oxadiazoles Have Butyrate-Specific Conditional Activity against Mycobacterium tuberculosis

    PubMed Central

    Early, Julie V.; Casey, Allen; Martinez-Grau, Maria Angeles; Gonzalez Valcarcel, Isabel C.; Vieth, Michal; Ollinger, Juliane; Bailey, Mai Ann; Alling, Torey; Files, Megan; Ovechkina, Yulia

    2016-01-01

    Mycobacterium tuberculosis is a global pathogen of huge importance which can adapt to several host niche environments in which carbon source availability is likely to vary. We developed and ran a phenotypic screen using butyrate as the sole carbon source to be more reflective of the host lung environment. We screened a library of ∼87,000 small compounds and identified compounds which demonstrated good antitubercular activity against M. tuberculosis grown with butyrate but not with glucose as the carbon source. Among the hits, we identified an oxadiazole series (six compounds) which had specific activity against M. tuberculosis but which lacked cytotoxicity against mammalian cells. PMID:27044545

  10. 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.

  11. Tetrahdroxysqualene from Rhus taitensis Shows Antimycobacterial Activity Against Mycobacterium tuberculosis

    PubMed Central

    Noro, Jeffrey C.; Barrows, Louis R.; Gideon, Osia G.; Ireland, Chris M.; Koch, Michael; Matainaho, Teatulohi; Piskaut, Pius; Pond, Christopher D.; Bugni, Tim S.

    2010-01-01

    Tuberculosis has become a major health problem, in particular with the emergence of extremely drug resistant tuberculosis (XDRTB). In our search for new therapeutic leads against TB, we isolated a new triterpene (1) from the plant Rhus taitensis collected in Papua New Guinea. Tetrahydroxysqualene (1) was isolated using bioassay-guided fractionation of the methanolic extract of R. taitensis leaves and twigs. The structure of tetrahydroxysqualene (1) was elucidated on the basis of HRESIMS and 1D and 2D NMR spectra. Tetrahydroxysqualene (1) exhibited anti–tuberculosis activity with an MIC of 10.0 μg/mL while showing only modest cytotoxicity. PMID:18710283

  12. Novel Cephalosporins Selectively Active on Nonreplicating Mycobacterium tuberculosis

    PubMed Central

    2016-01-01

    We report two series of novel cephalosporins that are bactericidal to Mycobacterium tuberculosis alone of the pathogens tested, which only kill M. tuberculosis when its replication is halted by conditions resembling those believed to pertain in the host, and whose bactericidal activity is not dependent upon or enhanced by clavulanate, a β-lactamase inhibitor. The two classes of cephalosporins bear an ester or alternatively an oxadiazole isostere at C-2 of the cephalosporin ring system, a position that is almost exclusively a carboxylic acid in clinically used agents in the class. Representatives of the series kill M. tuberculosis within macrophages without toxicity to the macrophages or other mammalian cells. PMID:27144688

  13. Spooky Suspects

    ERIC Educational Resources Information Center

    Pacifici, Lara

    2011-01-01

    This activity presents an option for covering biology content while engaging students in an investigation that highlights the spirit of Halloween. Students are engaged in the story line and have fun trying to solve the mystery kidnapping by using science skills to examine the evidence and eliminate some ghoulish suspects. (Contains 1 figure.)

  14. Immune parameters differentiating active from latent tuberculosis infection in humans.

    PubMed

    Lee, Ji Yeon; Jung, Young Won; Jeong, Ina; Joh, Joon-Sung; Sim, Soo Yeon; Choi, Boram; Jee, Hyeon-Gun; Lim, Dong-Gyun

    2015-12-01

    Tuberculosis remains a highly prevalent infectious disease worldwide. Identification of the immune parameters that differentiate active disease from latent infection will facilitate the development of efficient control measures as well as new diagnostic modalities for tuberculosis. Here, we investigated the cytokine production profiles of monocytes and CD4(+) T lymphocytes upon encountering mycobacterial antigens. In addition, cytokines and lipid mediators with immune-modulating activities were examined in plasma samples ex vivo. Comparison of these parameters in active tuberculosis patients and healthy subjects with latent infection revealed that, active tuberculosis was associated with diminished Th1-type cytokine secretion from CD4(+) T cells and less augmented inflammatory cytokine secretion from monocytes induced by IFN-γ than that in latent tuberculosis infection. In addition, a higher plasma concentration of lipoxin A4 and lower ratio of prostaglandin E2 to lipoxin A4 were observed in active cases than in latent infections. These findings have implications for preparing new therapeutic strategies and for differential diagnosis of the two types of tuberculosis infection.

  15. Clinical Predictors and Accuracy of Empiric Tuberculosis Treatment among Sputum Smear-Negative HIV-Infected Adult TB Suspects in Uganda

    PubMed Central

    Nakiyingi, Lydia; Bwanika, John Mark; Kirenga, Bruce; Nakanjako, Damalie; Katabira, Catherine; Lubega, Gloria; Sempa, Joseph; Nyesiga, Barnabas; Albert, Heidi; Manabe, Yukari C.

    2013-01-01

    Introduction The existing diagnostic algorithms for sputum smear-negative tuberculosis (TB) are complicated, time-consuming, and often difficult to implement. The decision to initiate TB treatment in resource-limited countries is often largely based on clinical predictors. We sought to determine the clinical predictors and accuracy of empiric TB treatment initiation in HIV-infected sputum smear-negative TB suspects using sputum culture as a reference standard. Setting Out-patient HIV-TB integrated urban clinic in Kampala, Uganda. Methods HIV-infected TB suspects were screened using sputum smear microscopy, and mycobacterial sputum liquid and solid cultures were performed. Smear results were made available to the clinician who made a clinical decision on empiric TB treatment initiation for sputum smear-negative patients. Clinic records were reviewed for patients whose sputum smears were negative to collect data on socio-demographics, TB symptomatology, chest X-ray findings, CD4 cell counts and TB treatment initiation. Results Of 253 smear-negative TB suspects, 56% (142/253) were females, median age 38 IQR (31–44) years, with a median CD4 cell count of 291 IQR (150–482) cells/mm3. Of the 85 (33.6%) smear-negative patients empirically initiated on TB treatment, 35.3% (n = 30) were sputum culture positive compared to only 18 (10.7%) of the 168 untreated patients (p<0.001). Abnormal chest X-ray [aOR 10.18, 95% CI (3.14–33.00), p<0.001] and advanced HIV clinical stage [aOR 3.92, 95% CI (1.20–12.85), p = 0.024] were significantly associated with empiric TB treatment initiation. The sensitivity and specificity of empiric TB treatment initiation in the diagnosis of TB in HIV-infected patients after negative smear microscopy was 62.5% and 73.7% respectively. Conclusion In resource-limited settings, clinically advanced HIV and abnormal chest X-ray significantly predict a clinical decision to empirically initiate TB treatment in smear-negative HIV

  16. Indoleamides are active against drug-resistant Mycobacterium tuberculosis

    PubMed Central

    Lun, Shichun; Guo, Haidan; Onajole, Oluseye K.; Pieroni, Marco; Gunosewoyo, Hendra; Chen, Gang; Tipparaju, Suresh K.; Ammerman, Nicole C.; Kozikowski, Alan P.; Bishai, William R.

    2014-01-01

    Responsible for nearly two million deaths each year, the infectious disease tuberculosis remains a serious global health challenge. The emergence of multidrug- and extensively drug-resistant strains of Mycobacterium tuberculosis confounds control efforts, and new drugs with novel molecular targets are desperately needed. Here we describe lead compounds, the indoleamides, with potent activity against both drug-susceptible and drug-resistant strains of M. tuberculosis by targeting the mycolic acid transporter MmpL3. We identify a single mutation in mmpL3 which confers high resistance to the indoleamide class while remaining susceptible to currently used first- and second-line tuberculosis drugs, indicating a lack of cross-resistance. Importantly, an indoleamide derivative exhibits dose-dependent anti-mycobacterial activity when orally administered to M. tuberculosis-infected mice. The bioavailability of the indoleamides, combined with their ability to kill tubercle bacilli, indicates great potential for translational developments of this structure class for the treatment of drug-resistant tuberculosis. PMID:24352433

  17. Cholesterol plays a larger role during Mycobacterium tuberculosis in vitro dormancy and reactivation than previously suspected.

    PubMed

    Soto-Ramirez, Maria D; Aguilar-Ayala, Diana A; Garcia-Morales, Lazaro; Rodriguez-Peredo, Sofia M; Badillo-Lopez, Claudia; Rios-Muñiz, Diana E; Meza-Segura, Mario A; Rivera-Morales, Gelen Y; Leon-Solis, Lizbel; Cerna-Cortes, Jorge F; Rivera-Gutierrez, Sandra; Helguera-Repetto, Addy C; Gonzalez-Y-Merchand, Jorge A

    2017-03-01

    It is known that cholesterol plays a key role for Mycobacterium tuberculosis (Mtb) adaptation and survival within the host, thus contributing to the establishment of dormancy. It has been extensively demonstrated that fatty acids are the main energy source of Mtb during infection and dormancy, and it has been proposed that these molecules are implicated in reactivation of bacilli from a dormant state. We used in vitro models to analyze Mtb gene expression during dormancy and reactivation when fatty acids and cholesterol are the unique carbon source in the media. Our results suggest that cholesterol might function as a signal to trigger Mtb expression of some genes required for stress protection earlier than the one induced by fatty acids alone, indicating that cholesterol is very favorable for its development. This process is so conducive that cholesterol-adapted bacilli can reactivate their growth after NRP2 dormancy state even 10 min post ventilation. Thus, we hypothesize that cholesterol is not only involved in Mtb dormancy but that it also plays a critical role for favorable and almost immediate reactivation from an in vitro long-lasting dormant state induced by hypoxia.

  18. Incremental Yield of Serial Sputum Cultures for Diagnosis of Tuberculosis among HIV Infected Smear Negative Pulmonary TB Suspects in Kampala, Uganda

    PubMed Central

    Ssengooba, Willy; Kiwanuka, Noah; Kateete, David P.; Katamba, Achilles; Joloba, Moses L.

    2012-01-01

    Background Sputum culture is the gold standard for diagnosis of pulmonary tuberculosis (PTB). Although mostly used for research, culture is recommended by the World Health Organization for TB diagnosis among HIV infected smear negative PTB suspects. Even then, the number of sputum samples required remains unspecified. Here, we determined the Incremental Yield (IY) and number of samples required to diagnose an additional PTB case upon second and third serial sputum culture. Methods/Findings This was a cross sectional study done between January and March 2011. Serial sputum samples were provided by participants within two days and cultured using Lowenstein Jensen (LJ) and Mycobacteria Growth Indicator Tube (MGIT) methods. A PTB case was defined as a positive culture on either one or both methods. The IY from the second and third serial cultures was determined and the reciprocal of the product of the fractions of IY provided the number of samples required for an additional PTB case. Of the 170 smear negative PTB suspects, 62 (36.5%) met the case definition. The IY of the second sample culture was 12.7%, 23.6% and 12.6% and for the third sample culture was 6.8%, 7.5% and 7.3% with LJ, MGIT and LJ or MGIT, respectively. The number of samples required for an additional PTB case and 95% CI upon the second sample culture were 29.9 (16.6, 156.5), 11.3 (7.6, 21.9) and 20.8 (12.5, 62.7); while for the third sample culture were 55.6 (26.4, 500.4), 35.7 (19.0, 313.8) and 36.1 (19.1, 330.9) by LJ, MGIT and LJ or MGIT respectively. Conclusions/Significance Among HIV infected smear negative PTB suspects in Kampala, 93% of PTB cases are diagnosed upon the second serial sputum culture. The number of cultures needed to diagnose an additional PTB case, ranges from 11–30 and 35–56 by the second and third sputum samples, respectively. PMID:22629439

  19. Tuberculosis.

    PubMed

    Dheda, Keertan; Barry, Clifton E; Maartens, Gary

    2016-03-19

    Although the worldwide incidence of tuberculosis has been slowly decreasing, the global disease burden remains substantial (∼9 million cases and ∼1·5 million deaths in 2013), and tuberculosis incidence and drug resistance are rising in some parts of the world such as Africa. The modest gains achieved thus far are threatened by high prevalence of HIV, persisting global poverty, and emergence of highly drug-resistant forms of tuberculosis. Tuberculosis is also a major problem in health-care workers in both low-burden and high-burden settings. Although the ideal preventive agent, an effective vaccine, is still some time away, several new diagnostic technologies have emerged, and two new tuberculosis drugs have been licensed after almost 50 years of no tuberculosis drugs being registered. Efforts towards an effective vaccine have been thwarted by poor understanding of what constitutes protective immunity. Although new interventions and investment in control programmes will enable control, eradication will only be possible through substantial reductions in poverty and overcrowding, political will and stability, and containing co-drivers of tuberculosis, such as HIV, smoking, and diabetes.

  20. Pathogen-derived biomarkers for active tuberculosis diagnosis.

    PubMed

    Tucci, Paula; González-Sapienza, Gualberto; Marin, Monica

    2014-01-01

    Tuberculosis (TB) is an infectious disease caused by members of Mycobacterium tuberculosis complex. Despite the availability of effective treatments, TB remains a major public health concern in most low and middle-income countries, representing worldwide the second leading cause of death from an infectious disease. Inadequate case detection and failures to classify the disease status hamper proper TB control. The limitations of the conventional diagnostic methods have encouraged much research activities in this field, but there is still an urgent need for an accurate point of care test for active TB diagnosis. A rapid, precise, and inexpensive TB diagnostic test would allow an earlier implementation of an appropriate treatment and the reduction of disease transmission. Pathogen-derived molecules present in clinical specimens of affected patients are being validated for that purpose. This short review aims to summarize the available data regarding biomarkers derived from M. tuberculosis, and their current usage in active TB diagnosis.

  1. A Focused Screen Identifies Antifolates with Activity on Mycobacterium tuberculosis

    PubMed Central

    Kumar, Anuradha; Colmenarejo, Gonzalo; Pérez, Esther; Gonzalez, Ruben R.; Torres, Pedro; Calvo, David; Gómez, Ruben M.; Ortega, Fátima; Jiménez, Elena; Gabarro, Raquel C.; Rullás, Joaquín; Ballell, Lluis

    2015-01-01

    Antifolates are widely used to treat several diseases but are not currently used in the first-line treatment of tuberculosis, despite evidence that some of these molecules can target Mycobacterium tuberculosis (Mtb) bacilli in vitro. To identify new antifolate candidates for animal-model efficacy studies of tuberculosis, we paired knowledge and tools developed in academia with the infrastructure and chemistry resources of a large pharmaceutical company. Together we curated a focused library of 2508 potential antifolates, which were then tested for activity against live Mtb. We identified 210 primary hits, confirmed the on-target activity of potent compounds, and now report the identification and characterization of 5 hit compounds, representative of 5 different chemical scaffolds. These antifolates have potent activity against Mtb and represent good starting points for improvement that could lead to in vivo efficacy studies. PMID:26771003

  2. 38 CFR 3.374 - Effect of diagnosis of active tuberculosis.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... active tuberculosis. 3.374 Section 3.374 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... Considerations Relative to Specific Diseases § 3.374 Effect of diagnosis of active tuberculosis. (a) Service diagnosis. Service department diagnosis of active pulmonary tuberculosis will be accepted unless a board...

  3. 38 CFR 3.374 - Effect of diagnosis of active tuberculosis.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... active tuberculosis. 3.374 Section 3.374 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... Considerations Relative to Specific Diseases § 3.374 Effect of diagnosis of active tuberculosis. (a) Service diagnosis. Service department diagnosis of active pulmonary tuberculosis will be accepted unless a board...

  4. 38 CFR 3.374 - Effect of diagnosis of active tuberculosis.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... active tuberculosis. 3.374 Section 3.374 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... Considerations Relative to Specific Diseases § 3.374 Effect of diagnosis of active tuberculosis. (a) Service diagnosis. Service department diagnosis of active pulmonary tuberculosis will be accepted unless a board...

  5. 38 CFR 3.374 - Effect of diagnosis of active tuberculosis.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... active tuberculosis. 3.374 Section 3.374 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... Considerations Relative to Specific Diseases § 3.374 Effect of diagnosis of active tuberculosis. (a) Service diagnosis. Service department diagnosis of active pulmonary tuberculosis will be accepted unless a board...

  6. 38 CFR 3.374 - Effect of diagnosis of active tuberculosis.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... active tuberculosis. 3.374 Section 3.374 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... Considerations Relative to Specific Diseases § 3.374 Effect of diagnosis of active tuberculosis. (a) Service diagnosis. Service department diagnosis of active pulmonary tuberculosis will be accepted unless a board...

  7. Active Tuberculosis Case Finding in Port-au-Prince, Haiti: Experiences, Results, and Implications for Tuberculosis Control Programs

    PubMed Central

    Delva, Guesly J.; Fort, Dumesle St.

    2016-01-01

    Background. Haiti has the highest tuberculosis (TB) prevalence in the Americas with 254 cases per 100,000 persons. Case detection relies on passive detection and TB services in many regions suffer from poor diagnostic and clinical resources. Methods. Mache Chache (“Go and Seek”) was a TB REACH Wave 3 funded TB case finding project in Port-au-Prince between July 2013 and September 2014, targeting four intervention areas with insufficient TB diagnostic performance. Results. Based on a verbal symptom screen emphasizing the presence of cough, the project identified 11,150 (11.75%) of all screened persons as TB subjects and 2.67% as smear-positive (SS+) TB cases. Enhanced case finding and strengthening of laboratory services led to a 59% increase in bacteriologically confirmed cases in the evaluation population. In addition, smear grades dropped significantly, suggesting earlier case detection. Xpert® MTB/RIF was successfully introduced and improved TB diagnosis in HIV-infected, smear-negative clinic patients, but not in HIV-negative, smear-negative TB suspects in the community. However, the number needed to screen for one additional SS+ case varied widely between clinic and community screening activities. Conclusion. Enhanced and active TB case finding in Haiti can improve TB diagnosis and care. However, screening algorithms have to be tailored to individual settings, necessitating long-term commitment. PMID:27668093

  8. Native New Zealand plants with inhibitory activity towards Mycobacterium tuberculosis

    PubMed Central

    2010-01-01

    Background Plants have long been investigated as a source of antibiotics and other bioactives for the treatment of human disease. New Zealand contains a diverse and unique flora, however, few of its endemic plants have been used to treat tuberculosis. One plant, Laurelia novae-zelandiae, was reportedly used by indigenous Maori for the treatment of tubercular lesions. Methods Laurelia novae-zelandiae and 44 other native plants were tested for direct anti-bacterial activity. Plants were extracted with different solvents and extracts screened for inhibition of the surrogate species, Mycobacterium smegmatis. Active plant samples were then tested for bacteriostatic activity towards M. tuberculosis and other clinically-important species. Results Extracts of six native plants were active against M. smegmatis. Many of these were also inhibitory towards M. tuberculosis including Laurelia novae-zelandiae (Pukatea). M. excelsa (Pohutukawa) was the only plant extract tested that was active against Staphylococcus aureus. Conclusions Our data provide support for the traditional use of Pukatea in treating tuberculosis. In addition, our analyses indicate that other native plant species possess antibiotic activity. PMID:20537175

  9. Nutritional supplements for people being treated for active tuberculosis

    PubMed Central

    Grobler, Liesl; Nagpal, Sukrti; Sudarsanam, Thambu D; Sinclair, David

    2016-01-01

    Background Tuberculosis and malnutrition are linked in a complex relationship. Tuberculosis may cause undernutrition through increased metabolic demands and decreased intake, and nutritional deficiencies may worsen the disease, or delay recovery by depressing important immune functions. At present, there is no evidence-based nutritional guidance for adults and children being treated for tuberculosis. Objectives To assess the effects of oral nutritional supplements in people being treated with antituberculous drug therapy for active tuberculosis. Search methods We searched the Cochrane Infectious Disease Group Specialized Register, Cochrane Central Register of Controlled Trials (CENTRAL; Issue 1, 2016), MEDLINE (from 1946 to 4 February 2016), EMBASE (from 1980 to 4 February 2016), LILACS (from 1982 to 4 February 2016), the metaRegister of Controlled Trials (mRCT), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), and the Indian Journal of Tuberculosis up to 4 February 2016, and checked the reference lists of all included studies. Selection criteria Randomized controlled trials that compared any oral nutritional supplement given for at least four weeks with no nutritional intervention, placebo, or dietary advice only for people being treated for active tuberculosis. The primary outcomes of interest were all-cause death, and cure at six and 12 months. Data collection and analysis Two review authors independently selected trials for inclusion, and extracted data and assessed the risk of bias in the included trials. We presented the results as risk ratios (RR) for dichotomous variables, and mean differences (MD) for continuous variables, with 95% confidence intervals (CIs). Where appropriate, we pooled data from trials with similar interventions and outcomes. We assessed the quality of the evidence using the Grading of Recommendation Assessment, Development and Evaluation (GRADE) approach. Main results Thirty-five trials

  10. Tuberculosis.

    PubMed

    Pearce, Lynne

    2017-03-10

    Essential facts Tuberculosis (TB) is an infection caused by a bacterium, mycobacterium tuberculosis. While it can affect any part of the body, only pulmonary TB is infectious. According to the charity TB Alert, there were 5,758 cases of TB in the UK in 2015 and 39% of them were in London. This represented a fall from a peak of 8,919 cases in 2011. Left untreated, TB is life-threatening, but is usually curable with antibiotics. The sooner it is diagnosed and treated, the better, both for the person's health and in preventing them from passing the infection on to others.

  11. Tuberculosis.

    PubMed

    Pearce, Lynne

    2017-02-22

    Essential facts Tuberculosis (TB) is an infection caused by a bacterium, mycobacterium tuberculosis. While it can affect any part of the body, only pulmonary TB is infectious. According to the charity TB Alert, there were 5,758 cases of TB in the UK in 2015 and 39% of them were in London. This represented a fall from a peak of 8,919 cases in 2011. Left untreated, TB is life-threatening, but is usually curable with antibiotics. The sooner it is diagnosed and treated, the better, both for the person's health and in preventing them from passing the infection on to others.

  12. LL-37 Immunomodulatory Activity during Mycobacterium tuberculosis Infection in Macrophages

    PubMed Central

    Torres-Juarez, Flor; Cardenas-Vargas, Albertina; Montoya-Rosales, Alejandra; González-Curiel, Irma; Garcia-Hernandez, Mariana H.; Enciso-Moreno, Jose A.; Hancock, Robert E. W.

    2015-01-01

    Tuberculosis is one of the most important infectious diseases worldwide. The susceptibility to this disease depends to a great extent on the innate immune response against mycobacteria. Host defense peptides (HDP) are one of the first barriers to counteract infection. Cathelicidin (LL-37) is an HDP that has many immunomodulatory effects besides its weak antimicrobial activity. Despite advances in the study of the innate immune response in tuberculosis, the immunological role of LL-37 during M. tuberculosis infection has not been clarified. Monocyte-derived macrophages were infected with M. tuberculosis strain H37Rv and then treated with 1, 5, or 15 μg/ml of exogenous LL-37 for 4, 8, and 24 h. Exogenous LL-37 decreased tumor necrosis factor alpha (TNF-α) and interleukin-17 (IL-17) while inducing anti-inflammatory IL-10 and transforming growth factor β (TGF-β) production. Interestingly, the decreased production of anti-inflammatory cytokines did not reduce antimycobacterial activity. These results are consistent with the concept that LL-37 can modulate the expression of cytokines during mycobacterial infection and this activity was independent of the P2X7 receptor. Thus, LL-37 modulates the response of macrophages during infection, controlling the expression of proinflammatory and anti-inflammatory cytokines. PMID:26351280

  13. Alteration of serum inflammatory cytokines in active pulmonary tuberculosis following anti-tuberculosis drug therapy.

    PubMed

    Chowdhury, Imran Hussain; Ahmed, Albin Mostaque; Choudhuri, Subhadip; Sen, Aditi; Hazra, Avijit; Pal, Nishith Kumar; Bhattacharya, Basudev; Bahar, Bojlul

    2014-11-01

    Active pulmonary tuberculosis (APTB) is associated with a failure of the host immune system to control the invading Mycobacterium tuberculosis (Mtb). The objective of this study was to quantify and assess the role of serum inflammatory cytokines in active pulmonary tuberculosis patients following anti-tuberculosis drug (ATD) therapy. Blood samples were collected from APTB patients and normal healthy subjects (NHS) (total n=204) at baseline and 2, 4 and 6 months post-therapy and the abundance of serum inflammatory cytokines were measured by cytokine specific ELISA. Compared to NHS, APTB patients at baseline had higher levels of serum pro-inflammatory cytokines IL-12p40 (P<0.001), IFN-γ (P<0.001), TNF-α (P<0.01), IL-1β (P<0.001) and IL-6 (P<0.001) and anti-inflammatory cytokines IL-10 (P<0.001) and TGF-β1 (P<0.001) while there was no change in the level of IL-4. In APTB patients, the serum levels of IFN-γ, TNF-α, IL-6 and TGF-β1 directly relate to the bacterial load while the TNF-α, IL-1β, IL-6 and TGF-β1 relate to radiological severity. At baseline, the IL-6 level in NHS and APTB patients differed most and following ATD therapy, this level rapidly decreased and stabilized by 4-month in APTB patients. It is concluded that a subtle reduction in the serum level of IL-6 of the APTB patients following ATD therapy might play a vital role in immune-protection of the host against Mtb infection and hence the serum IL-6 level can be a useful marker to diagnose the effectiveness of therapy in the patients.

  14. Progression to active tuberculosis, but not transmission, varies by M. tuberculosis lineage in The Gambia

    PubMed Central

    de Jong, Bouke C.; Hill, Philip C.; Aiken, Alex; Awine, Timothy; Antonio, Martin; Adetifa, Ifedayo M.; Jackson-Sillah, Dolly J.; Fox, Annette; DeRiemer, Kathryn; Gagneux, Sebastien; Borgdorff, Martien W.; McAdam, Keith P.W.J.; Corrah, Tumani; Small, Peter M.; Adegbola, Richard A.

    2008-01-01

    Considerable variability exists in the outcome of M. tuberculosis infection. We hypothesized that M. africanum was less likely than M. tuberculosis to transmit and progress to tuberculosis disease. In a cohort study of tuberculosis patients and their household contacts in the Gambia, we categorized 1,808 HIV negative tuberculosis contacts according to exposure to M. tuberculosis or to M. africanum. A positive skin test indicated transmission and development of tuberculosis during 2 years of follow-up indicated progression to disease. Transmission was similar, but progression to disease was significantly lower in contacts exposed to M. africanum than to M. tuberculosis (1.0% vs 2.9%; Hazard Ratio (HR) 3.1, 95% CI 1.1–8.7). Within M. tuberculosis sensu stricto, contacts exposed to a Beijing family strain were most likely to progress to disease (5.6%; HR 6.7 (2.0–22) relative to M. africanum). M. africanum and M. tuberculosis transmit equally well to household contacts, but contacts exposed to M. africanum are less likely to progress to tuberculosis disease than those exposed to M. tuberculosis. The variable rate of progression by lineage suggests that TB variability matters in clinical settings and should be taken into account in studies evaluating tuberculosis vaccines and treatment regimens for latent tuberculosis infection. PMID:18702608

  15. Rv3168 phosphotransferase activity mediates kanamycin resistance in Mycobacterium tuberculosis.

    PubMed

    Ahn, Jae-Woo; Kim, Kyung-Jin

    2013-11-28

    Tuberculosis is a worldwide epidemic disease caused by Mycobacterium tuberculosis, with an estimated one-third of the human population currently affected. Treatment of this disease with aminoglycoside antibiotics has become less effective owing to antibiotic resistance. Recent determination of the crystal structure of the M. tuberculosis Rv3168 protein suggests a structure similar to that of Enterococcus faecalis APH(3')-IIIa, and that this protein may be an aminoglycoside phosphotransferase. To determine whether Rv3168 confers antibiotic resistance against kanamycin, we performed dose-response antibiotic resistance experiments using kanamycin. Expression of the Rv3168 protein in Escherichia coli conferred antibiotic resistance against 100 μM kanamycin, a concentration that effected cell growth arrest in the parental E. coli strain and an E. coli strain expressing the Rv3168(D249A) mutant, in which the catalytic Asp249 residue was mutated to alanine. Furthermore, we detected phosphotransferase activity of Rv3168 against kanamycin as a substrate. Moreover, docking simulation of kanamycin into the Rv3168 structure suggests that kanamycin fits well into the substrate binding pocket of the protein, and that the phosphorylation-hydroxyl-group of kanamycin was located at a position similar to that in E. faecalis APH(3')-IIIa. On the basis of these results, we suggest that the Rv3168 mediates kanamycin resistance in M. tuberculosis, likely through phosphotransferase targeting of kanamycin.

  16. LAG3 expression in active Mycobacterium tuberculosis infections.

    PubMed

    Phillips, Bonnie L; Mehra, Smriti; Ahsan, Muhammad H; Selman, Moises; Khader, Shabaana A; Kaushal, Deepak

    2015-03-01

    Mycobacterium tuberculosis (MTB) is a highly successful pathogen because of its ability to persist in human lungs for long periods of time. MTB modulates several aspects of the host immune response. Lymphocyte-activation gene 3 (LAG3) is a protein with a high affinity for the CD4 receptor and is expressed mainly by regulatory T cells with immunomodulatory functions. To understand the function of LAG3 during MTB infection, a nonhuman primate model of tuberculosis, which recapitulates key aspects of natural human infection in rhesus macaques (Macaca mulatta), was used. We show that the expression of LAG3 is highly induced in the lungs and particularly in the granulomatous lesions of macaques experimentally infected with MTB. Furthermore, we show that LAG3 expression is not induced in the lungs and lung granulomas of animals exhibiting latent tuberculosis infection. However, simian immunodeficiency virus-induced reactivation of latent tuberculosis infection results in an increased expression of LAG3 in the lungs. This response is not observed in nonhuman primates infected with non-MTB bacterial pathogens, nor with simian immunodeficiency virus alone. Our data show that LAG3 was expressed primarily on CD4(+) T cells, presumably by regulatory T cells but also by natural killer cells. The expression of LAG3 coincides with high bacterial burdens and changes in the host type 1 helper T-cell response.

  17. Burden of tuberculosis in Kampala, Uganda.

    PubMed Central

    Guwatudde, David; Zalwango, Sarah; Kamya, Moses R.; Debanne, Sara M.; Diaz, Mireya I.; Okwera, Alphonse; Mugerwa, Roy D.; King, Charles; Whalen, Christopher C.

    2003-01-01

    OBJECTIVE: To determine the prevalence and incidence of tuberculosis in one of Uganda's poor peri-urban areas. METHODS: Multi-stage sampling was used to select a sample of households whose members were evaluated for presence of signs and/or symptoms of active tuberculosis; history of tuberculosis treatment; and relevant demographic, socioeconomic, and household environment characteristics. Patients with suspected tuberculosis underwent standardized evaluation for active disease. FINDINGS: A sample of 263 households with 1142 individuals was evaluated. Nineteen people were classified as having had tuberculosis during the one-year reference period (May 2001-April 2002): nine (47%) cases already had been diagnosed through the health care system, while 10 cases (53%) were diagnosed through the survey. The prevalences for all forms of tuberculosis and for sputum smear-positive tuberculosis were 14.0 (95% confidence interval (CI) 7.8-20.3) and 4.4 (CI = 0.83-7.89) per thousand, respectively. The incidences for all forms of tuberculosis and for sputum smear-positive tuberculosis were 9.2 (CI = 3.97-14.4) and 3.7 (CI = 0.39-6.95) per thousand per year, respectively. CONCLUSION: The rate of tuberculosis in this peri-urban community was exceptionally high and may be underestimated by current surveillance systems. The need for interventions aimed at reducing tuberculosis transmission in this, and other similar communities with high case rates, is urgent. PMID:14758406

  18. Tuberculosis.

    PubMed

    Jacobson, Karen R

    2017-02-07

    This issue provides a clinical overview of tuberculosis, focusing on screening, prevention, diagnosis, and treatment. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers.

  19. Chromospheric activity in Delta Scuti stars - The suspected variable Tau Cygni

    NASA Technical Reports Server (NTRS)

    Fracassini, M.; Pasinetti Fracassini, L. E.; Mariani, A.; Pastori, L.; Teays, T. J.

    1991-01-01

    High-resolution IUE spectra of the suspected variable Tau Cyg were obtained to search for a possible variability of the Mg II h, k double-peaked emission. The observations, spanning an interval of about 6.3 h, have shown flux excursions within or just near 15 percent, a value suggested as the detection limit of actual variations with IUE spectra. A variability, difficult to explain, could be present in the ratios Fk2v/Fk2r. The emission fluxes seem to be higher than those of the Delta Scuti variables Rho Pup and Beta Cas. This comparison could give some insights on the possible role of the convection on the pulsational and chromospheric activities of Tau Cyg. A positive correlation between the total emission fluxes and the rotational velocities of these stars was found.

  20. Tuberculosis of the manubriosternal joint and concurrent asymptomatic active pulmonary tuberculosis in a patient presenting with a chest wall mass.

    PubMed

    Gorospe, Luis; Ayala-Carbonero, Ana María; Rodríguez-Díaz, Ricardo; García Latorre, Raquel; Muñoz-Molina, Gemma María; Cabañero-Sánchez, Alberto

    2015-01-01

    A 62-year-old woman presented to our hospital with an anterior chest wall swelling. Computed tomography (CT) and magnetic resonance imaging showed findings consistent with an infectious arthritis of the manubriosternal joint, and CT images also demonstrated multiple centrilobular nodules in both lungs, suggesting an infectious bronchiolitis. A CT-guided fine needle aspiration of a presternal mass yielded growth of Mycobacterium tuberculosis. Bronchoalveolar lavage confirmed an active pulmonary tuberculosis. Septic arthritis of the manubriosternal joint is exceedingly rare.

  1. Evaluation of the characteristics of the enzyme-linked immunospot assay for diagnosis of active tuberculosis in China.

    PubMed

    Wang, Linchuan; Yu, Yan; Chen, Wei; Feng, Jin; Wang, Jinyuan; Zhao, Heping; Ma, Lietin; Yang, Bo; Ma, Yanfen; Dang, Pei

    2015-05-01

    The purpose of this study was to evaluate the characteristics of the T-SPOT.TB test for the diagnosis of active tuberculosis (ATB) and to distinguish ATB from other diseases using a receiver operating characteristic (ROC) curve. A total of 535 patients with suspected active tuberculosis were enrolled in the study and divided into ATB and nonactive tuberculosis (NATB) groups, as well as pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB) subgroups. The sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio of the T-SPOT.TB test for the diagnosis of ATB were 84.95%, 85.12%, 82.94%, 86.93%, 5.71, and 0.18, respectively. The median number of spot-forming cells (SFCs) in the ATB group was higher than that in the NATB group (71 versus 1; P < 0.0001). The sensitivities in the PTB and EPTB subgroups were 92.31% and 81.77%. The areas under the curve (AUC) for the diagnosis of ATB using the T-SPOT.TB, early secreted antigenic target 6 (ESAT-6), and culture filtrate protein 10 (CFP-10) were 0.906, 0.884, and 0.877, respectively. A cutoff of 42.5 SFCs for ATB yielded a positive predictive value of 100%. Our study shows that the T-SPOT.TB test is useful for the diagnosis of ATB. Utilizing an ROC curve to select an appropriate cutoff made it possible to discriminate ATB from NATB.

  2. Anaerobic incubation conditions enhance pyrazinamide activity against Mycobacterium tuberculosis.

    PubMed

    Wade, Mary Margaret; Zhang, Ying

    2004-08-01

    Pyrazinamide (PZA) is an unconventional front line tuberculosis drug characterized by high in vivo sterilizing activity, but poor in vitro activity. This disparity in PZA activity may reflect differences between the in vivo tissue environment and in vitro culture conditions. This study examined the effect of anaerobic conditions, which exist in granulomatous lesions in vivo, on PZA activity in vitro. Low oxygen enhanced the activity of PZA against Mycobacterium tuberculosis, with anaerobic conditions resulting in greater enhancement than microaerobic conditions. ATPase and respiratory chain enzyme inhibitors enhanced PZA activity under normal atmospheric conditions, but not under anaerobic conditions. Furthermore, the inhibitors did not enhance isoniazid or rifampicin activity. Nitrate as an alternative electron acceptor antagonized PZA activity under anaerobic conditions. These findings provide further support for a proposed mechanism of action of PZA in which the active form of PZA (pyrazinoic acid) depletes the membrane energy reserve. They also provide another explanation for the higher sterilizing activity of PZA within in vivo lesions with low oxygen than under in vitro drug susceptibility testing conditions with ambient oxygen.

  3. Anti-Mycobacterium tuberculosis activity of fungus Phomopsis stipata

    PubMed Central

    de Prince, Karina Andrade; Sordi, Renata; Pavan, Fernando Rogério; Barreto Santos, Adolfo Carlos; Araujo, Angela R.; Leite, Sergio R.A.; Leite, Clarice Q. F.

    2012-01-01

    Our purpose was to determine the anti-Mycobacterium tuberculosis activity of the metabolites produced by the endophitic fungus Phomopsis stipata (Lib.) B. Sutton, (Diaporthaceae), cultivated in different media. The antimycobacterial activity was assessed through the Resazurin Microtiter Assay (REMA) and the cytotoxicity test performed on macrophage cell line. The extracts derived from fungi grown on Corn Medium and Potato Dextrose Broth presented the smallest values of Minimum Inhibitory Concentration (MIC) and low cytotoxicity, which implies a high selectivity index. This is the first report on the chemical composition and antitubercular activity of metabolites of P. stipata, as well as the influence of culture medium on these properties. PMID:24031821

  4. Lipophilic pyrazinoic acid amide and ester prodrugs stability, activation and activity against M. tuberculosis.

    PubMed

    Simões, Marta Filipa; Valente, Emília; Gómez, M José Rodríguez; Anes, Elsa; Constantino, Luís

    2009-06-28

    Pyrazinamide (PZA) is active against M. tuberculosis and is a first line agent for the treatment of human tuberculosis. PZA is itself a prodrug that requires activation by a pyrazinamidase to form its active metabolite pyrazinoic acid (POA). Since the specificity of cleavage is dependent on a single bacterial enzyme, resistance to PZA is often found in tuberculosis patients. Esters of POA have been proposed in the past as alternatives to PZA however the most promising compounds were rapidly degraded in the presence of serum. In order to obtain compounds that could survive during the transport phase, we synthesized lipophilic ester and amide POA derivatives, studied their activity against M. tuberculosis, their stability in plasma and rat liver homogenate and also their activation by a mycobacterial homogenate. The new lipophilic ester prodrugs were found to be active in concentrations 10-fold lower than those needed for PZA to kill sensitive M. tuberculosis and also have a suitable stability in the presence of plasma. Amides of POA although more stable in plasma have lower activity. The reason can probably be found in the rate of activation of both types of prodrugs; while esters are easily activated by mycobacterial esterases, amides are resistant to activation and are not transformed into POA at a suitable rate.

  5. Persisting PET-CT lesion activity and M. tuberculosis mRNA after pulmonary tuberculosis cure

    PubMed Central

    Malherbe, Stephanus T.; Shenai, Shubhada; Ronacher, Katharina; Loxton, Andre G.; Dolganov, Gregory; Kriel, Magdalena; Van, Tran; Chen, Ray Y.; Warwick, James; Via, Laura E.; Song, Taeksun; Lee, Myungsun; Schoolnik, Gary; Tromp, Gerard; Alland, David; Barry, Clifton E.; Winter, Jill; Walzl, Gerhard

    2016-01-01

    The absence of a gold standard to determine when antibiotics have induced sterilizing cure confounds the development of new approaches to treat pulmonary tuberculosis (PTB). We detected PET-CT imaging response patterns consistent with active disease along with the presence of Mycobacterium tuberculosis mRNA in sputum and bronchoalveolar lavage samples in a substantial proportion of adult, HIV-negative PTB patients after standard 6-month treatment plus one year follow-up, including patients with a durable cure and others who later developed recurrent disease. The presence of MTB mRNA in the context of non-resolving and intensifying lesions on PET-CT might indicate ongoing transcription, suggesting that even apparently curative PTB treatment may not eradicate all organisms in most patients. This suggests an important complementary role for the immune response in maintaining a disease-free state. Sterilizing drugs or host-directed therapies and better treatment response markers are likely needed for the successful development of improved and shortened PTB treatment strategies. PMID:27595324

  6. Effect of Active Case Finding on Prevalence and Transmission of Pulmonary Tuberculosis in Dhaka Central Jail, Bangladesh

    PubMed Central

    Banu, Sayera; Rahman, Md. Toufiq; Uddin, Mohammad Khaja Mafij; Khatun, Razia; Khan, Md. Siddiqur Rahman; Rahman, Md. Mojibur; Uddin, Syed Iftekhar; Ahmed, Tahmeed; Heffelfinger, James D.

    2015-01-01

    Background Understanding tuberculosis (TB) transmission dynamics is essential for establishing effective TB control strategies in settings where the burden and risk of transmission are high. The objectives of this study were to evaluate the effect of active screening on controlling TB transmission and also to characterize Mycobacterium tuberculosis strains for investigating transmission dynamics in a correctional setting. Methods The study was carried out in Dhaka Central Jail (DCJ), from October 2005 to February 2010. An active case finding strategy for pulmonary TB was established both at the entry point to the prison and inside the prison. Three sputum specimens were collected from all pulmonary TB suspects and subjected to smear microscopy, culture, and drug susceptibility testing as well as genotyping which included deletion analysis, spoligotyping and analysis of mycobacterial interspersed repetitive units (MIRU). Results A total of 60,585 inmates were screened during the study period. We found 466 inmates with pulmonary TB of whom 357 (77%) had positive smear microscopy results and 109 (23%) had negative smear microscopy results but had positive results on culture. The number of pulmonary TB cases declined significantly, from 49 cases during the first quarter to 8 cases in the final quarter of the study period (p=0.001). Deletion analysis identified all isolates as M. tuberculosis and further identified 229 (70%) strains as ‘modern’ and 100 (30%) strains as ‘ancestral’. Analysis of MIRU showed that 347 strains (85%) exhibited unique patterns, whereas 61 strains (15%) clustered into 22 groups. The largest cluster comprised eight strains of the Beijing M. tuberculosis type. The rate of recent transmission was estimated to be 9.6%. Conclusions Implementation of active screening for TB was associated with a decline in TB cases in DCJ. Implementation of active screening in prison settings might substantially reduce the national burden of TB in Bangladesh

  7. Activation of the Wnt Pathway by Mycobacterium tuberculosis: A Wnt–Wnt Situation

    PubMed Central

    Villaseñor, Tomás; Madrid-Paulino, Edgardo; Maldonado-Bravo, Rafael; Urbán-Aragón, Antonio; Pérez-Martínez, Leonor; Pedraza-Alva, Gustavo

    2017-01-01

    Mycobacterium tuberculosis (M. tuberculosis), an intracellular pathogenic Gram-positive bacterium, is the cause of tuberculosis (TB), a major worldwide human infectious disease. The innate immune system is the first host defense against M. tuberculosis. The recognition of this pathogen is mediated by several classes of pattern recognition receptors expressed on the host innate immune cells, including Toll-like receptors, Nod-like receptors, and C-type lectin receptors like Dectin-1, the Mannose receptor, and DC-SIGN. M. tuberculosis interaction with any of these receptors activates multiple signaling pathways among which the protein kinase C, the MAPK, and the NFκB pathways have been widely studied. These pathways have been implicated in macrophage invasion, M. tuberculosis survival, and impaired immune response, thus promoting a successful infection and disease. Interestingly, the Wnt signaling pathway, classically regarded as a pathway involved in the control of cell proliferation, migration, and differentiation in embryonic development, has recently been involved in immunoregulatory mechanisms in infectious and inflammatory diseases, such as TB, sepsis, psoriasis, rheumatoid arthritis, and atherosclerosis. In this review, we present the current knowledge supporting a role for the Wnt signaling pathway during macrophage infection by M. tuberculosis and the regulation of the immune response against M. tuberculosis. Understanding the cross talk between different signaling pathways activated by M. tuberculosis will impact on the search for new therapeutic targets to fuel the rational design of drugs aimed to restore the immunological response against M. tuberculosis. PMID:28203237

  8. Activation of the Wnt Pathway by Mycobacterium tuberculosis: A Wnt-Wnt Situation.

    PubMed

    Villaseñor, Tomás; Madrid-Paulino, Edgardo; Maldonado-Bravo, Rafael; Urbán-Aragón, Antonio; Pérez-Martínez, Leonor; Pedraza-Alva, Gustavo

    2017-01-01

    Mycobacterium tuberculosis (M. tuberculosis), an intracellular pathogenic Gram-positive bacterium, is the cause of tuberculosis (TB), a major worldwide human infectious disease. The innate immune system is the first host defense against M. tuberculosis. The recognition of this pathogen is mediated by several classes of pattern recognition receptors expressed on the host innate immune cells, including Toll-like receptors, Nod-like receptors, and C-type lectin receptors like Dectin-1, the Mannose receptor, and DC-SIGN. M. tuberculosis interaction with any of these receptors activates multiple signaling pathways among which the protein kinase C, the MAPK, and the NFκB pathways have been widely studied. These pathways have been implicated in macrophage invasion, M. tuberculosis survival, and impaired immune response, thus promoting a successful infection and disease. Interestingly, the Wnt signaling pathway, classically regarded as a pathway involved in the control of cell proliferation, migration, and differentiation in embryonic development, has recently been involved in immunoregulatory mechanisms in infectious and inflammatory diseases, such as TB, sepsis, psoriasis, rheumatoid arthritis, and atherosclerosis. In this review, we present the current knowledge supporting a role for the Wnt signaling pathway during macrophage infection by M. tuberculosis and the regulation of the immune response against M. tuberculosis. Understanding the cross talk between different signaling pathways activated by M. tuberculosis will impact on the search for new therapeutic targets to fuel the rational design of drugs aimed to restore the immunological response against M. tuberculosis.

  9. The Transcriptional Signature of Active Tuberculosis Reflects Symptom Status in Extra-Pulmonary and Pulmonary Tuberculosis

    PubMed Central

    Blankley, Simon; Graham, Christine M.; Turner, Jacob; Berry, Matthew P. R.; Bloom, Chloe I.; Xu, Zhaohui; Pascual, Virginia; Banchereau, Jacques; Chaussabel, Damien; Breen, Ronan; Santis, George; Blankenship, Derek M.; Lipman, Marc; O’Garra, Anne

    2016-01-01

    Background Mycobacterium tuberculosis infection is a leading cause of infectious death worldwide. Gene-expression microarray studies profiling the blood transcriptional response of tuberculosis (TB) patients have been undertaken in order to better understand the host immune response as well as to identify potential biomarkers of disease. To date most of these studies have focused on pulmonary TB patients with gene-expression profiles of extra-pulmonary TB patients yet to be compared to those of patients with pulmonary TB or sarcoidosis. Methods A novel cohort of patients with extra-pulmonary TB and sarcoidosis was recruited and the transcriptional response of these patients compared to those with pulmonary TB using a variety of transcriptomic approaches including testing a previously defined 380 gene meta-signature of active TB. Results The 380 meta-signature broadly differentiated active TB from healthy controls in this new dataset consisting of pulmonary and extra-pulmonary TB. The top 15 genes from this meta-signature had a lower sensitivity for differentiating extra-pulmonary TB from healthy controls as compared to pulmonary TB. We found the blood transcriptional responses in pulmonary and extra-pulmonary TB to be heterogeneous and to reflect the extent of symptoms of disease. Conclusions The transcriptional signature in extra-pulmonary TB demonstrated heterogeneity of gene expression reflective of symptom status, while the signature of pulmonary TB was distinct, based on a higher proportion of symptomatic individuals. These findings are of importance for the rational design and implementation of mRNA based TB diagnostics. PMID:27706152

  10. Prevalence, Risk Factors and Social Context of Active Pulmonary Tuberculosis among Prison Inmates in Tajikistan

    PubMed Central

    Winetsky, Daniel E.; Almukhamedov, Olga; Pulatov, Dilshod; Vezhnina, Natalia; Dooronbekova, Aizhan; Zhussupov, Baurzhan

    2014-01-01

    Setting Tuberculosis (TB) is highly prevalent in prisons of the former Soviet Union. Objective To understand the behavioral, demographic and biological factors placing inmates in Tajikistan at risk for active TB. Design We administered a behavioral and demographic survey to 1317 inmates in two prison facilities in Sughd province, Tajikistan along with radiographic screening for pulmonary TB. Suspected cases were confirmed bacteriologically. Inmates undergoing TB treatment were also surveyed. In-depth interviews were conducted with former prisoners to elicit relevant social and behavioral characteristics. Results We identified 59 cases of active pulmonary TB (prevalence 4.5%). Factors independently associated with increased prevalence of active TB were: HIV-infection by self-report (PR 7.88; 95%CI 3.40–18.28), history of previous TB (PR 10.21; 95%CI 6.27–16.63) and infrequent supplemental nutrition beyond scheduled meals (PR 3.00; 95%CI 1.67–5.62). Access to supplemental nutrition was associated with frequency of visits from friends and family and ability to rely on other inmates for help. Conclusion In prison facilities of Tajikistan, HIV-infection, injection drug use and low access to supplemental nutrition were associated with prevalent cases of active pulmonary TB. Policies that reduce HIV transmission among injection drug users and improve the nutritional status of socially isolated inmates may alleviate the TB burden in Tajikistan’s prisons. PMID:24465861

  11. Mycobacterium tuberculosis Lipolytic Enzymes as Potential Biomarkers for the Diagnosis of Active Tuberculosis

    PubMed Central

    Brust, Belinda; Lecoufle, Mélanie; Tuaillon, Edouard; Dedieu, Luc; Canaan, Stéphane; Valverde, Viviane; Kremer, Laurent

    2011-01-01

    Background New diagnosis tests are urgently needed to address the global tuberculosis (TB) burden and to improve control programs especially in resource-limited settings. An effective in vitro diagnostic of TB based on serological methods would be regarded as an attractive progress because immunoassays are simple, rapid, inexpensive, and may offer the possibility to detect cases missed by standard sputum smear microscopy. However, currently available serology tests for TB are highly variable in sensitivity and specificity. Lipolytic enzymes have recently emerged as key factors in lipid metabolization during dormancy and/or exit of the non-replicating growth phase, a prerequisite step of TB reactivation. The focus of this study was to analyze and compare the potential of four Mycobacterium tuberculosis lipolytic enzymes (LipY, Rv0183, Rv1984c and Rv3452) as new markers in the serodiagnosis of active TB. Methods Recombinant proteins were produced and used in optimized ELISA aimed to detect IgG and IgM serum antibodies against the four lipolytic enzymes. The capacity of the assays to identify infection was evaluated in patients with either active TB or latent TB and compared with two distinct control groups consisting of BCG-vaccinated blood donors and hospitalized non-TB individuals. Results A robust humoral response was detected in patients with active TB whereas antibodies against lipolytic enzymes were infrequently detected in either uninfected groups or in subjects with latent infection. High specifity levels, ranging from 93.9% to 97.5%, were obtained for all four antigens with sensitivity values ranging from 73.4% to 90.5%, with Rv3452 displaying the highest performances. Patients with active TB usually exhibited strong IgG responses but poor IgM responses. Conclusion These results clearly indicate that the lipolytic enzymes tested are strongly immunogenic allowing to distinguish active from latent TB infections. They appear as potent biomarkers providing high

  12. Determinants of active pulmonary tuberculosis in Ambo Hospital, West Ethiopia

    PubMed Central

    Mengiste, Bezatu; Mesfin, Frehiwot; Godana, Wanzahun

    2015-01-01

    Objectives The aim of this study was to determine factors associated with active pulmonary tuberculosis seen in cases in Ambo Hospital, Ethiopia. Design A facility-based prospective case-control study. Setting Patients attending Ambo Hospital from 01 December 2011 to 29 March 2012. Participants The sample included 312 adult patients attending Ambo Hospital. The main outcome measure was presence of active pulmonary tuberculosis (TB). Explanatory measures Age, gender, occupation, educational status, marital status, place of residence, patient history of TB, family history of TB, human immunodeficiency virus (HIV) infection, smoking, alcohol intake, khat chewing, body mass index (BMI), employment, diabetes, history of asthma, previous history of worm infestation, history of hospitalisation, number of adults living in the household (HH), person per room, housing condition. Results A total of 312 study participants, including 104 active pulmonary tuberculosis (PTB) cases (cases) and 208 non-active PTB cases (controls), were recruited for the present study. Having one or more family member with a history of TB (OR = 4.4; 95% CI: 1.50–12.90), marital status (OR = 7.6; 95% CI: 2.2–12.6), male gender (OR = 3.2; 95% CI: 1.4–7), rural residence (OR = 3.3; P = 0.012), being a current or past smoker (OR = 2.8; 95% CI: 1.1–7.2), BMI < 18.5 (OR = 2.1; 95% CI: 1.03–4.2), HIV infection (OR = 8.8; 95% CI: 2.4–23.8) and a history of worm infestation (OR = 6.4; 95% CI: 2.6–15.4) remained significant independent host-related factors for active PTB. Conclusion Patients who came from a compound with more than two HHs were more likely to develop active PTB than those who came from a compound with only one HH. Those who lived in houses with no windows were more likely to develop active PTB than those who lived in houses with one or more windows, had a family history of TB, lived in rural areas. Sex of the patient was a predicting factor. Not being the owner of the house was

  13. Plasma drug activity assay for treatment optimization in tuberculosis patients.

    PubMed

    Heysell, Scott K; Mtabho, Charles; Mpagama, Stellah; Mwaigwisya, Solomon; Pholwat, Suporn; Ndusilo, Norah; Gratz, Jean; Aarnoutse, Rob E; Kibiki, Gibson S; Houpt, Eric R

    2011-12-01

    Low antituberculosis (TB) drug levels are common, but their clinical significance remains unclear, and methods of measurement are resource intensive. Subjects initiating treatment for sputum smear-positive pulmonary TB were enrolled from Kibong'oto National TB Hospital, Tanzania, and levels of isoniazid, rifampin, ethambutol, and pyrazinamide were measured at the time of typical peak plasma concentration (C(2 h)). To evaluate the significance of the effect of observed drug levels on Mycobacterium tuberculosis growth, a plasma TB drug activity (TDA) assay was developed using the Bactec MGIT system. Time to detection of plasma-cocultured M. tuberculosis versus time to detection of control growth was defined as a TDA ratio. TDA assays were later performed using the subject's own M. tuberculosis isolate and C(2 h) plasma from the Tanzanian cohort and compared to drug levels and clinical outcomes. Sixteen subjects with a mean age of 37.8 years ± 10.7 were enrolled. Fourteen (88%) had C(2 h) rifampin levels and 11 (69%) had isoniazid levels below 90% of the lower limit of the expected range. Plasma spiked with various concentrations of antituberculosis medications found TDA assay results to be unaffected by ethambutol or pyrazinamide. Yet with a range of isoniazid and rifampin concentrations, TDA exhibited a statistically significant correlation with drug level and drug MIC, and a TDA of ~1.0 indicated the presence of multidrug-resistant TB. In Tanzania, low (≤ 2.0) TDA was significantly associated with both lower isoniazid and rifampin C(2 h) levels, and very low (≤ 1.5) TDA corresponded to a trend toward lack of cure. Study of TDA compared to additional clinical outcomes and as a therapeutic management tool is warranted.

  14. 38 CFR 3.378 - Changes from activity in pulmonary tuberculosis pension cases.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Changes from activity in pulmonary tuberculosis pension cases. 3.378 Section 3.378 Pensions, Bonuses, and Veterans' Relief DEPARTMENT... tuberculosis pension cases. A permanent and total disability rating in effect during hospitalization will...

  15. 38 CFR 3.378 - Changes from activity in pulmonary tuberculosis pension cases.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Changes from activity in pulmonary tuberculosis pension cases. 3.378 Section 3.378 Pensions, Bonuses, and Veterans' Relief DEPARTMENT... tuberculosis pension cases. A permanent and total disability rating in effect during hospitalization will...

  16. 38 CFR 3.378 - Changes from activity in pulmonary tuberculosis pension cases.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Changes from activity in pulmonary tuberculosis pension cases. 3.378 Section 3.378 Pensions, Bonuses, and Veterans' Relief DEPARTMENT... tuberculosis pension cases. A permanent and total disability rating in effect during hospitalization will...

  17. 38 CFR 3.378 - Changes from activity in pulmonary tuberculosis pension cases.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Changes from activity in pulmonary tuberculosis pension cases. 3.378 Section 3.378 Pensions, Bonuses, and Veterans' Relief DEPARTMENT... tuberculosis pension cases. A permanent and total disability rating in effect during hospitalization will...

  18. 38 CFR 3.378 - Changes from activity in pulmonary tuberculosis pension cases.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Changes from activity in pulmonary tuberculosis pension cases. 3.378 Section 3.378 Pensions, Bonuses, and Veterans' Relief DEPARTMENT... tuberculosis pension cases. A permanent and total disability rating in effect during hospitalization will...

  19. Discriminating Active Tuberculosis from Latent Tuberculosis Infection by flow cytometric measurement of CD161-expressing T cells

    PubMed Central

    Yang, Qianting; Xu, Qian; Chen, Qi; Li, Jin; Zhang, Mingxia; Cai, Yi; Liu, Haiying; Zhou, Yiping; Deng, Guofang; Deng, Qunyi; Zhou, Boping; Kornfeld, Hardy; Chen, Xinchun

    2015-01-01

    Interferon-gamma Release Assays (IGRAs) significantly increases the possibility for early diagnosis of tuberculosis, but IGRAs alone cannot discriminate active TB from LTBI. Therefore, fast and reliable discrimination of active tuberculosis, especially bacteriology negative tuberculosis, from LTBI is a great necessity. Here we established an assay based on flow cytometric multiparameter assay assessing expression of CD161 along with CD3, CD4, and CD8, whereby a set of indices formulated by the percentages of CD3+CD161+, CD3+CD4+CD161+ and CD3+CD8+CD161+ T cells multiplied with lymphocyte/monocyte ratio were established. Application of the CD3+CD8+CD161+ index to compare a cohort of active tuberculosis with a cohort of LTBI or health control yielded 0.7662 (95% confidence interval [CI] 0.6559–0.8552) or 0.7922 (95%  CI 0.6846–0.8763) for sensitivity and 0.9048 (95%  CI 0.8209–0.9580) or 0.8939 (95% CI 0.8392–0.9349) for specificity when the TB cohort was AFB+; the corresponding results were 0.7481 (95%  CI 0.6648–0.8198) or 0.7557 (95%  CI 0.6730–0.8265) for sensitivity and 0.8571 (95%  CI 0.7637–0.9239) or 0.8603 (95%  CI 0.8008–0.9075) for specificity when the TB cohort was AFB−. Our results reveal that in combination with IGRAs, CD161-based indices provide a novel, fast diagnostic solution addressing the limitation of current tuberculosis diagnostics. PMID:26643453

  20. Alternative activation deprives macrophages of a coordinated defense program to Mycobacterium tuberculosis.

    PubMed

    Kahnert, Antje; Seiler, Peter; Stein, Maik; Bandermann, Silke; Hahnke, Karin; Mollenkopf, Hans; Kaufmann, Stefan H E

    2006-03-01

    A potent Th1 immune response is critical to the control of tuberculosis. The impact of an additive Th2 response on the course of disease has so far been insufficiently characterized, despite increased morbidity after co-infection with Mycobacterium tuberculosis and Th2-eliciting helminths and possible involvement of Th2 polarization in reactivation of latent tuberculosis. Here, we describe the gene expression profile of murine bone marrow-derived macrophages alternatively activated by IL-4 in response to infection with M. tuberculosis. Comparison of transcriptional profiles of infected IL-4- and IFN-gamma-activated macrophages revealed delayed and partially diminished responses to intracellular bacteria in alternatively activated macrophages, characterized by reduced exposure to nitrosative stress and increased iron availability, respectively. Alternative activation of host macrophages correlated with elevated expression of the M. tuberculosis iron storage protein bacterioferritin as well as reduced expression of the mycobactin synthesis genes mbtI and mbtJ. The extracellular matrix-remodeling enzyme matrix metalloproteinase (MMP)-12 was induced in alternatively activated macrophages in vitro, and MMP-12-expressing macrophages were abundant at late, but not early, stages of tuberculosis in murine lungs. Our findings emphasize that alternative activation deprives macrophages of control mechanisms that limit mycobacterial growth in vivo, thus supporting intracellular persistence of M. tuberculosis.

  1. Mycobacterium tuberculosis 19-kDa lipoprotein promotes neutrophil activation.

    PubMed

    Neufert, C; Pai, R K; Noss, E H; Berger, M; Boom, W H; Harding, C V

    2001-08-01

    Certain microbial substances, e.g., LPS, can activate neutrophils or prime them to enhance their response to other activating agents, e.g., fMLP. We investigated the role of the Mycobacterium tuberculosis (MTB) 19-kDa lipoprotein in activation of human neutrophils. MTB 19-kDa lipoprotein initiated phenotypic changes characteristic of neutrophil activation, including down-regulation of CD62 ligand (L-selectin) and up-regulation of CD35 (CR1) and CD11b/CD18 (CR3, Mac-1). In addition, exposure of neutrophils to MTB 19-kDa lipoprotein enhanced the subsequent oxidative burst in response to fMLP as assessed by oxidation of dihydrorhodamine 123 (determined by flow cytometry). LPS also produced these effects with similar kinetics, but an oligodeoxynucleotide containing a CpG motif failed to induce any priming or activation response. Although the effects of LPS required the presence of serum, neutrophil activation by MTB 19-kDa lipoprotein occurred independently of serum factors, suggesting the involvement of different receptors and signaling mechanisms for LPS and MTB 19-kDa lipoprotein. Thus, MTB 19-kDa lipoprotein serves as a pathogen-associated molecular pattern that promotes neutrophil priming and activation.

  2. The Cyclic Peptide Ecumicin Targeting ClpC1 Is Active against Mycobacterium tuberculosis In Vivo

    PubMed Central

    Gao, Wei; Kim, Jin-Yong; Anderson, Jeffrey R.; Akopian, Tatos; Hong, Seungpyo; Jin, Ying-Yu; Kandror, Olga; Kim, Jong-Woo; Lee, In-Ae; Lee, Sun-Young; McAlpine, James B.; Mulugeta, Surafel; Sunoqrot, Suhair; Wang, Yuehong; Yang, Seung-Hwan; Yoon, Tae-Mi; Goldberg, Alfred L.; Pauli, Guido F.; Cho, Sanghyun

    2014-01-01

    Drug-resistant tuberculosis (TB) has lent urgency to finding new drug leads with novel modes of action. A high-throughput screening campaign of >65,000 actinomycete extracts for inhibition of Mycobacterium tuberculosis viability identified ecumicin, a macrocyclic tridecapeptide that exerts potent, selective bactericidal activity against M. tuberculosis in vitro, including nonreplicating cells. Ecumicin retains activity against isolated multiple-drug-resistant (MDR) and extensively drug-resistant (XDR) strains of M. tuberculosis. The subcutaneous administration to mice of ecumicin in a micellar formulation at 20 mg/kg body weight resulted in plasma and lung exposures exceeding the MIC. Complete inhibition of M. tuberculosis growth in the lungs of mice was achieved following 12 doses at 20 or 32 mg/kg. Genome mining of lab-generated, spontaneous ecumicin-resistant M. tuberculosis strains identified the ClpC1 ATPase complex as the putative target, and this was confirmed by a drug affinity response test. ClpC1 functions in protein breakdown with the ClpP1P2 protease complex. Ecumicin markedly enhanced the ATPase activity of wild-type (WT) ClpC1 but prevented activation of proteolysis by ClpC1. Less stimulation was observed with ClpC1 from ecumicin-resistant mutants. Thus, ClpC1 is a valid drug target against M. tuberculosis, and ecumicin may serve as a lead compound for anti-TB drug development. PMID:25421483

  3. Combining PMTCT with active case finding for tuberculosis.

    PubMed

    Kali, Paula B N; Gray, Glenda E; Violari, Avy; Chaisson, Richard E; McIntyre, James A; Martinson, Neil A

    2006-07-01

    Tuberculosis (TB) is the preeminent manifestation of HIV infection and has become a leading cause of maternal mortality and morbidity in high HIV-prevalence settings. Active TB in pregnant women has potentially serious consequences for fetuses and newborns. In Soweto, South Africa, there is a more than 90% uptake of voluntary counseling and HIV testing during routine antenatal care, and almost one third of pregnant women are HIV-infected. The posttest counseling session of the prevention of mother-to-child transmission program provides an opportunity to screen HIV-infected pregnant women for TB. In this study, 370 HIV-infected pregnant women were screened for symptoms of active TB by lay counselors at the posttest counseling session. If symptomatic, they were referred to nurses who investigated them further. Eight women were found to have previously undiagnosed, smear-negative, culture-confirmed TB (2160/100,000). The mean CD4 count in those with active TB compared to those without TB was 276 x 10(6) cells per liter vs 447 x 10(6) cells per liter (P = 0.051). Symptoms most associated with active TB were hemoptysis and fever. We conclude that rates of TB in HIV-infected pregnant women are high, and screening for TB during routine antenatal care should be implemented in high HIV-prevalence settings.

  4. Mycobacterium tuberculosis enhances human immunodeficiency virus-1 replication by transcriptional activation at the long terminal repeat.

    PubMed Central

    Zhang, Y; Nakata, K; Weiden, M; Rom, W N

    1995-01-01

    Tuberculosis has emerged as an epidemic fueled by the large number of individuals infected with the human immunodeficiency virus, especially those who are injecting drug users. We found a striking increase from 4- to 208-fold in p24 levels in bronchoalveolar lavage fluid from involved sites of Mycobacterium tuberculosis infection vs uninvolved sites in three HIV+ patients. We used an in vitro cell culture model to determine if tuberculosis could activate replication of HIV-1. Mononuclear phagocyte cell lines U937 and THP-1 infected with HIV-1JR-CSF, in vitro and stimulated with live M. tuberculosis H37Ra, had a threefold increase in p24 in culture supernatants. Using the HIV-1 long terminal repeat with a chloramphenicol acetyltransferase (CAT) reporter construct, live M. tuberculosis increased transcription 20-fold in THP-1 cells, and cell wall components stimulated CAT expression to a lesser extent. The nuclear factor-kappa B enhancer element was responsible for the majority of the increased CAT activity although two upstream nuclear factor-IL6 sites may also contribute to enhanced transcription. Antibodies to TNF-alpha and IL-1 inhibited the increase in CAT activity of the HIV-1 long terminal repeat by M. tuberculosis from 21-fold to 8-fold. Stimulation of HIV-1 replication by M. tuberculosis may exacerbate dysfunction of the host immune response in dually infected individuals. Images PMID:7738195

  5. RP105 facilitates macrophage activation by Mycobacterium tuberculosis lipoproteins.

    PubMed

    Blumenthal, Antje; Kobayashi, Toshihiko; Pierini, Lynda M; Banaei, Niaz; Ernst, Joel D; Miyake, Kensuke; Ehrt, Sabine

    2009-01-22

    RP105, phylogenetically related to Toll-like receptor (TLR)-4, is reported to facilitate B cell activation by the TLR4-agonist lipopolysaccharide (LPS)--but to limit LPS-induced cytokine production by antigen-presenting cells. Here, we show that the role of RP105 extends beyond LPS recognition and that RP105 positively regulates macrophage responses to Mycobacterium tuberculosis (Mtb) lipoproteins. Mtb-infected RP105(-/-) mice exhibited impaired proinflammatory cytokine responses associated with enhanced bacterial burden and increased lung pathology. The Mtb 19 kDa lipoprotein induced release of tumor necrosis factor in a manner dependent on both TLR2 and RP105, and macrophage activation by Mtb lacking mature lipoproteins was not RP105 dependent. Thus, mycobacterial lipoproteins are RP105 agonists. RP105 physically interacted with TLR2, and both RP105 and TLR2 were required for optimal macrophage activation by Mtb. Our data identify RP105 as an accessory molecule for TLR2, forming part of the receptor complex for innate immune recognition of mycobacterial lipoproteins.

  6. Iron-dependent RNA-binding activity of Mycobacterium tuberculosis aconitase.

    PubMed

    Banerjee, Sharmistha; Nandyala, Ashok Kumar; Raviprasad, Podili; Ahmed, Niyaz; Hasnain, Seyed E

    2007-06-01

    Cellular iron levels are closely monitored by iron regulatory and sensor proteins of Mycobacterium tuberculosis for survival inside macrophages. One such class of proteins systematically studied in eukaryotes and reported in a few prokaryotes are the iron-responsive proteins (IRPs). These IRPs bind to iron-responsive elements (IREs) present at untranslated regions (UTRs) of mRNAs and are responsible for posttranscriptional regulation of the expression of proteins involved in iron homeostasis. Amino acid sequence analysis of M. tuberculosis aconitase (Acn), a tricarboxylic acid (TCA) cycle enzyme, showed the presence of the conserved residues of the IRP class of proteins. We demonstrate that M. tuberculosis Acn is bifunctional. It is a monomeric protein that is enzymatically active in converting isocitrate to cis-aconitate at a broad pH range of 7 to 10 (optimum, pH 8). As evident from gel retardation assays, M. tuberculosis Acn also behaves like an IRP by binding to known mammalian IRE-like sequences and to predicted IRE-like sequences present at the 3' UTR of thioredoxin (trxC) and the 5' UTR of the iron-dependent repressor and activator (ideR) of M. tuberculosis. M. tuberculosis Acn when reactivated with Fe(2+) functions as a TCA cycle enzyme, but upon iron depletion by a specific iron chelator, it behaves like an IRP, binding to the selected IREs in vitro. Since iron is required for the Acn activity and inhibits the RNA-binding activity of Acn, the two activities of M. tuberculosis Acn are mutually exclusive. Our results demonstrate the bifunctional nature of M. tuberculosis Acn, pointing to its likely role in iron homeostasis.

  7. Active screening at entry for tuberculosis among new immigrants: a systematic review and meta-analysis.

    PubMed

    Arshad, S; Bavan, L; Gajari, K; Paget, S N J; Baussano, I

    2010-06-01

    Although there is no evidence that imported tuberculosis increases the incidence of the disease in host countries, the rise in migration worldwide raises concerns regarding the adequacy of surveillance and control of immigrant-associated tuberculosis in low incidence countries. Assessing the performance of screening of immigrants for tuberculosis is key to rationalizing control policies for the detection and management of immigrant-associated tuberculosis. We performed a systematic review and meta-analysis to determine the yield of active screening for tuberculosis among new immigrants at the point of entry. The yield for pulmonary tuberculosis was 3.5 cases per 1,000 screened (95% CI 2.9-4.1; I(2) = 94%); for refugees, asylum seekers and regular immigrants the estimates were 11.9 (95% CI 6.7-17.2; I(2) = 92%), 2.8 (95% CI 2.0-3.7; I(2) = 96%) and 2.7 (95% CI 2.0-3.4; I(2) = 81%), respectively. The yield estimates for immigrants from Europe, Africa and Asia were 2.4 (95% CI 1.3-3.4; I(2) = 51.5%), 6.5 (95% CI 3.2-10.0; I(2) = 62%) and 11.2 (95% CI 6.2-16.1; I(2) = 95%), respectively. These results provide useful data to inform the development of coherent policies and rational screening services for the detection of immigrant-associated tuberculosis.

  8. Targeting dendritic cells to accelerate T-cell activation overcomes a bottleneck in tuberculosis vaccine efficacy

    PubMed Central

    Griffiths, Kristin L.; Ahmed, Mushtaq; Das, Shibali; Gopal, Radha; Horne, William; Connell, Terry D.; Moynihan, Kelly D.; Kolls, Jay K.; Irvine, Darrell J.; Artyomov, Maxim N.; Rangel-Moreno, Javier; Khader, Shabaana A.

    2016-01-01

    The development of a tuberculosis (TB) vaccine that induces sterilizing immunity to Mycobacterium tuberculosis infection has been elusive. Absence of sterilizing immunity induced by TB vaccines may be due to delayed activation of mucosal dendritic cells (DCs), and subsequent delay in antigen presentation and activation of vaccine-induced CD4+ T-cell responses. Here we show that pulmonary delivery of activated M. tuberculosis antigen-primed DCs into vaccinated mice, at the time of M. tuberculosis exposure, can overcome the delay in accumulation of vaccine-induced CD4+ T-cell responses. In addition, activating endogenous host CD103+ DCs and the CD40–CD40L pathway can similarly induce rapid accumulation of vaccine-induced lung CD4+ T-cell responses and limit early M. tuberculosis growth. Thus, our study provides proof of concept that targeting mucosal DCs can accelerate vaccine-induced T-cell responses on M. tuberculosis infection, and provide insights to overcome bottlenecks in TB vaccine efficacy. PMID:28004802

  9. Pyrazinamide Is Active against Mycobacterium tuberculosis Cultures at Neutral pH and Low Temperature.

    PubMed

    den Hertog, Alice L; Menting, Sandra; Pfeltz, Richard; Warns, Matthew; Siddiqi, Salman H; Anthony, Richard M

    2016-08-01

    For the past decades, an acidic pH has been used to render Mycobacterium tuberculosis susceptible to pyrazinamide for in vitro testing. Here, we show that at the standard breakpoint concentration and reduced culture temperatures, pyrazinamide (PZA) is active against tuberculosis (TB) at neutral pH. This finding should help unravel the mechanism of action of PZA and allow drug susceptibility testing (DST) methods to be optimized.

  10. Screening strategies for active tuberculosis: focus on cost-effectiveness

    PubMed Central

    Dobler, Claudia Caroline

    2016-01-01

    In recent years, there has been renewed interest in screening for active tuberculosis (TB), also called active case-finding (ACF), as a possible means to achieve control of the global TB epidemic. ACF aims to increase the detection of TB, in order to diagnose and treat patients with TB earlier than if they had been diagnosed and treated only at the time when they sought health care because of symptoms. This will reduce or avoid secondary transmission of TB to other people, with the long-term goal of reducing the incidence of TB. Here, the history of screening for active TB, current screening practices, and the role of TB-diagnostic tools are summarized and the literature on cost-effectiveness of screening for active TB reviewed. Cost-effectiveness analyses indicate that community-wide ACF can be cost-effective in settings with a high incidence of TB. ACF among close TB contacts is cost-effective in settings with a low as well as a high incidence of TB. The evidence for cost-effectiveness of screening among HIV-infected persons is not as strong as for TB contacts, but the reviewed studies suggest that the intervention can be cost-effective depending on the background prevalence of TB and test volume. None of the cost-effectiveness analyses were informed by data from randomized controlled trials. As the results of randomized controlled trials evaluating different ACF strategies will become available in future, we will hopefully gain a better understanding of the role that ACF can play in achieving global TB control. PMID:27418848

  11. Mycobacterium tuberculosis Activates Human Macrophage Peroxisome Proliferator-Activated Receptor γ Linking Mannose Receptor Recognition to Regulation of Immune Responses

    PubMed Central

    Rajaram, Murugesan V. S.; Brooks, Michelle N.; Morris, Jessica D.; Torrelles, Jordi B.; Azad, Abul K.; Schlesinger, Larry S.

    2010-01-01

    Mycobacterium tuberculosis enhances its survival in macrophages by suppressing immune responses in part through its complex cell wall structures. Peroxisome proliferator-activated receptor γ (PPARγ), a nuclear receptor superfamily member, is a transcriptional factor that regulates inflammation and has high expression in alternatively activated alveolar macrophages and macrophage-derived foam cells, both cell types relevant to tuberculosis pathogenesis. In this study, we show that virulent M. tuberculosis and its cell wall mannose-capped lipoarabinomannan induce PPARγ expression through a macrophage mannose receptor-dependent pathway. When activated, PPARγ promotes IL-8 and cyclooxygenase 2 expression, a process modulated by a PPARγ agonist or antagonist. Upstream, MAPK-p38 mediates cytosolic phospholipase A2 activation, which is required for PPARγ ligand production. The induced IL-8 response mediated by mannose-capped lipoarabinomannan and the mannose receptor is independent of TLR2 and NF-κB activation. In contrast, the attenuated Mycobacterium bovis bacillus Calmette-Guérin induces less PPARγ and preferentially uses the NF-κB–mediated pathway to induce IL-8 production. Finally, PPARγ knockdown in human macrophages enhances TNF production and controls the intracellular growth of M. tuberculosis. These data identify a new molecular pathway that links engagement of the mannose receptor, an important pattern recognition receptor for M. tuberculosis, with PPARγ activation, which regulates the macrophage inflammatory response, thereby playing a role in tuberculosis pathogenesis. PMID:20554962

  12. Role of the Health Department in Tuberculosis Prevention and Control-Legal and Public Health Considerations.

    PubMed

    Jeffries, Carla; Lobue, Phil; Chorba, Terence; Metchock, Beverly; Kashef, Ijaz

    2017-03-01

    Because tuberculosis is caused by an infectious organism that is spread from person to person through the air, public health measures are essential to control the disease. There are three priority strategies for tuberculosis prevention and control in the United States: (i) identifying and treating persons who have tuberculosis disease; (ii) finding persons exposed to infectious tuberculosis patients, evaluating them for Mycobacterium tuberculosis infection and disease, and providing subsequent treatment, if appropriate; and (iii) testing populations at high risk for latent tuberculosis infection (LTBI) and treating those persons who are infected to prevent progression to disease. These strategies for prevention and control of tuberculosis are discussed in a framework containing the following important topics: historical and epidemiological context of tuberculosis control, organization of public health tuberculosis control programs, legal basis for public health authority, conducting overall planning and development of policy, identifying persons who have clinically active tuberculosis, evaluation of immigrants, managing persons who have or who are suspected of having disease, medical consultation, interjurisdictional referrals, identifying and managing persons infected with Mycobacterium tuberculosis, providing laboratory and diagnostic services, collecting and analyzing data, and providing training and education. This chapter describes the role of the health department in the context of these components. This discussion is primarily applicable to tuberculosis prevention and control programs in the United States.

  13. Mycobacterium tuberculosis activates the DNA-dependent cytosolic surveillance pathway within macrophages.

    PubMed

    Manzanillo, Paolo S; Shiloh, Michael U; Portnoy, Daniel A; Cox, Jeffery S

    2012-05-17

    Cytosolic bacterial pathogens activate the cytosolic surveillance pathway (CSP) and induce innate immune responses, but how the host detects vacuolar pathogens like Mycobacterium tuberculosis is poorly understood. We show that M. tuberculosis also initiates the CSP upon macrophage infection via limited perforation of the phagosome membrane mediated by the ESX-1 secretion system. Although the bacterium remains within the phagosome, this permeabilization results in phagosomal and cytoplasmic mixing and allows extracellular mycobacterial DNA to access host cytosolic receptors, thus blurring the distinction between "vacuolar" and "cytosolic" pathogens. Activation of cytosolic receptors induces signaling through the Sting/Tbk1/Irf3 axis, resulting in IFN-β production. Surprisingly, Irf3(-/-) mice, which cannot respond to cytosolic DNA, are resistant to long-term M. tuberculosis infection, suggesting that the CSP promotes M. tuberculosis infection. Thus, cytosolic sensing of mycobacterial DNA plays a key role in M. tuberculosis pathogenesis and likely contributes to the high type I IFN signature in tuberculosis.

  14. Phenotypes of lung mononuclear phagocytes in HIV seronegative tuberculosis patients: evidence for new recruitment and cell activation.

    PubMed

    Lapa e Silva, J R; Linhares, C; Boechat, N; Rego, L; Almeida, M G; Kriski, A L; Ho, J L

    1996-01-01

    Mycobacterium tuberculosis preferentially resides in mononuclear phagocytes. The mechanisms by which mononuclear phagocytes keep M. tuberculosis in check or by which the microbe evades control to cause disease remain poorly understood. As an initial effort to delineate these mechanisms, we examined by immunostaining the phenotype of mononuclear phagocytes obtained from lungs of patients with active tuberculosis. From August 1994 to March 1995, consecutive patients who had an abnormal chest X-ray, no demonstrable acid-fast bacilli in sputum specimens and required a diagnostic bronchoalveolar lavage (BAL) were enrolled. Of the 39 patients enrolled, 21 had microbiologically diagnosed tuberculosis. Thirteen of the 21 tuberculosis patients were either HIV seronegative (n = 12) or had no risk factor for HIV and constituted the tuberculosis group. For comparison, M. tuberculosis negative patients who had BAL samples taken during this time (n = 9) or normal healthy volunteers (n = 3) served as control group. Compared to the control group, the tuberculosis group had significantly higher proportion of cells expressing markers of young monocytes (UCHM1) and RFD7, a marker for phagocytic cells, and increased expression of HLA-DR, a marker of cell activation. In addition, tuberculosis group had significantly higher proportion of cells expressing dendritic cell marker (RFD1) and epithelioid cell marker (RFD9). These data suggest that despite recruitment of monocytes probably from the peripheral blood and local cell activation, host defense of the resident lung cells is insufficient to control M. tuberculosis.

  15. [Guidelines for the diagnosis and treatment of latent tuberculosis infection and active tuberculosis in patients with inflammatory joint diseases proposed for treatment with tumour necrosis factor alpha antagonist drugs].

    PubMed

    Fonseca, João Eurico; Lucas, Helena; Canhão, Helena; Duarte, Raquel; Santos, Maria José; Villar, Miguel; Faustino, Augusto; Raymundo, Elena

    2006-01-01

    The Portuguese Society of Rheumatology (SPR) and the Portuguese Society of Pulmonology (SPP) have developed guidelines for the diagnosis and treatment of latent tuberculosis infection (LTBI) and active tuberculosis (AT) in patients with inflammatory joint diseases (IJD), namely rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis, treated with tumour necrosis factor alpha (TNF-a) antagonists. Due to the high risk of tuberculosis (TB) in patients with IJD, LTBI and AT screening should be performed as soon as possible, ideally at the moment of IJD diagnosis. Even if TB screening was performed at the beginning of the disease, the evaluation should be repeated before starting anti-TNF-a therapy. When TB (LTBI or AT) treatment is indicated, it should be performed before the beginning of anti-TNF-a therapy. If the IJD activity requires urgent anti-TNF-a therapy, these drugs can be started after two months of antituberculosis therapy in AT cases, or after one month in LTBI cases. Chest X-ray is mandatory for all patients. If abnormal, e.g. Gohn complex, the patient should be treated as LTBI; residual lesions require the exclusion of AT and patients with history of untreated or incomplete TB treatment should be treated as LTBI. In cases of suspected active lesions, AT diagnosis should be confirmed and adequate therapy initiated. Tuberculin skin test (TST), with two units of RT23, should be performed in all patients. If induration is less than 5 mm, the test should be repeated after 1 to 2 weeks, on the opposite forearm, and should be considered negative if the result is again inferior to 5 mm. Positive TST implicates LTBI treatment. If TST is performed in immunosuppressed IJD patients, LTBI treatment should be offered to the patient before starting anti-TNF-a therapy, even in the presence of a negative test.

  16. IFNG-mediated immune responses enhance autophagy against Mycobacterium tuberculosis antigens in patients with active tuberculosis

    PubMed Central

    Rovetta, Ana I; Peña, Delfina; Hernández Del Pino, Rodrigo E; Recalde, Gabriela M; Pellegrini, Joaquín; Bigi, Fabiana; Musella, Rosa M; Palmero, Domingo J; Gutierrez, Marisa; Colombo, María I; García, Verónica E

    2015-01-01

    Protective immunity against Mycobacterium tuberculosis (Mtb) requires IFNG. Besides, IFNG-mediated induction of autophagy suppresses survival of virulent Mtb in macrophage cell lines. We investigated the contribution of autophagy to the defense against Mtb antigen (Mtb-Ag) in cells from tuberculosis patients and healthy donors (HD). Patients were classified as high responders (HR) if their T cells produced significant IFNG against Mtb-Ag; and low responders (LR) when patients showed weak or no T cell responses to Mtb-Ag. The highest autophagy levels were detected in HD cells whereas the lowest quantities were observed in LR patients. Interestingly, upon Mtb-Ag stimulation, we detected a positive correlation between IFNG and MAP1LC3B-II/LC3-II levels. Actually, blockage of Mtb-Ag-induced IFNG markedly reduced autophagy in HR patients whereas addition of limited amounts of IFNG significantly increased autophagy in LR patients. Therefore, autophagy collaborates with human immune responses against Mtb in close association with specific IFNG secreted against the pathogen. PMID:25426782

  17. A Dual Read-Out Assay to Evaluate the Potency of Compounds Active against Mycobacterium tuberculosis

    PubMed Central

    Ollinger, Juliane; Bailey, Mai Ann; Moraski, Garrett C.; Casey, Allen; Florio, Stephanie; Alling, Torey; Miller, Marvin J.; Parish, Tanya

    2013-01-01

    Tuberculosis is a serious global health problem caused by the bacterium Mycobacterium tuberculosis. There is an urgent need for discovery and development of new treatments, but this can only be accomplished through rapid and reproducible M. tuberculosis assays designed to identify potent inhibitors. We developed an automated 96-well assay utilizing a recombinant strain of M. tuberculosis expressing a far-red fluorescent reporter to determine the activity of novel compounds; this allowed us to measure growth by monitoring both optical density and fluorescence. We determined that optical density and fluorescence were correlated with cell number during logarithmic phase growth. Fluorescence was stably maintained without antibiotic selection over 5 days, during which time cells remained actively growing. We optimized parameters for the assay, with the final format being 5 days’ growth in 96-well plates in the presence of 2% w/v DMSO. We confirmed reproducibility using rifampicin and other antibiotics. The dual detection method allows for a reproducible calculation of the minimum inhibitory concentration (MIC), at the same time detecting artefacts such as fluorescence quenching or compound precipitation. We used our assay to confirm anti-tubercular activity and establish the structure activity relationship (SAR) around the imidazo[1,2-a]pyridine-3-carboxamides, a promising series of M. tuberculosis inhibitors. PMID:23593234

  18. The Structure Activity Relationship of Urea Derivatives as Anti-Tuberculosis Agents

    PubMed Central

    Brown, Joshua R.; North, Elton J.; Hurdle, Julian G.; Morisseau, Christophe; Scarborough, Jerrod S.; Sun, Dianqing; Korduláková, Jana; Scherman, Michael S.; Jones, Victoria; Grzegorzewicz, Anna; Crew, Rebecca M.; Jackson, Mary; McNeil, Michael R.; Lee, Richard E.

    2011-01-01

    The treatment of tuberculosis is becoming more difficult due to the ever increasing prevalence of drug resistance. Thus, it is imperative that novel anti-tuberculosis agents, with unique mechanisms of action, be discovered and developed. The direct anti-tubercular testing of a small compound library led to discovery of adamantyl urea hit compound 1. In this study, the hit was followed up through the synthesis of an optimization library. This library was generated by systematically replacing each section of the molecule with a similar moiety until a clear structure activity relationship was obtained with respect to anti-tubercular activity. The best compounds in this series contained a 1-adamantyl-3-phenyl urea core and had potent activity against Mycobacterium tuberculosis plus an acceptable therapeutic index. It was noted that the compounds identified and the pharmacophore developed is consistent with inhibitors of epoxide hydrolase family of enzymes. Consequently, the compounds were tested for inhibition of representative epoxide hydrolases: M. tuberculosis EphB and EphE; and human soluble epoxide hydrolase. Many of the optimized inhibitors showed both potent EphB and EphE inhibition suggesting the antitubercular activity is through inhibition of multiple epoxide hydrolyase enzymes. The inhibitors also showed potent inhibition of humans soluble expoxide hydrolyase, but limited cytotoxicity suggesting that future studies must be towards increasing the selectivity of epoxide hydrolyase inhibition towards the M. tuberculosis enzymes. PMID:21840723

  19. [Development and study of structure-activity relationship of drugs against Mycobacterium tuberculosis].

    PubMed

    Baska, Ferenc; Székely, Edina Rita; Szántai-Kis, Csaba; Bánhegyi, Péter; Hegymegi-Barakonyi, Bálint; Németh, Gábor; Breza, Nóra; Zsákai, Lilian; Greff, Zoltán; Pató, János; Kéri, György; Orfi, Lászlo

    2013-01-01

    Tuberculosis is considered to be one of the major health problem not only in the less developed countries but in the economically developed countries as well. Roughly one third of the world's population are infected with Mycobacterium tuberculosis and a significant part of them are carriers of latent tuberculosis. From ten percent of these latent infections are developing the active TB disease and fifty percent of them die from the illness without appropriate treatment. The drug-resistant Mycobacterium tuberculosis (MDR-TB, XDR-TB) and TB-HIV co-infection attracted attention to the most serious infectious disease. Inhibition of alternative signaling pathways were an important part of the research strategies for cancer and inflammatory diseases in recent years. In case of Mycobacterium tuberculosis such pathways were also identified, for example, three serine-threonine kinases (PknA, PknB, PknG) which are necessary and essential for bacterial growth. In this paper we summarize our best anti-TB active compounds, their biological effects and structure-activity relationships using in silico modeling, biochemical measurements and tests on active bacteria.

  20. Specific lytic activity against mycobacterial antigens is inversely correlated with the severity of tuberculosis

    PubMed Central

    DE LA BARRERA, S S; FINIASZ, M; FRIAS, A; ALEMÁN, M; BARRIONUEVO, P; FINK, S; FRANCO, M C; ABBATE, E; SASIAIN, M Del C

    2003-01-01

    The ability of peripheral blood mononuclear cells (PBMC) from patients with active tuberculosis to display cytotoxic responses against autologous Mycobacterium tuberculosis (Mtb)-pulsed macrophages was evaluated. Non-MHC restricted cell-dependent lytic activity was observed in ex vivo effector cells from tuberculosis patients and was mediated mainly by CD3+γδ TCR+ T (γδ T) cells bearing CD56 and/or CD16 molecules. MHC-restricted and non-MHC restricted cytotoxic T cells (CTL) were differentially expanded upon stimulation with Mtb in tuberculosis patients and normal controls (N). Class-I restricted CD8+ CTL and class-II restricted CD4+ CTL were generated in PPD+N and to a lesser extent in PPD–N. Mtb-stimulated effector cells from tuberculosis patients became progressively non-MHC restricted CD4–CD8–γδ T cells, while lytic activity of CD4+ and CD8+CTL decreased gradually as the disease became more severe. On the other hand, target cells were lysed by ex vivo cells from tuberculosis patients through the Fas-FasL and perforin pathways. Mtb-induced CD4+ CTL from tuberculosis patients and N controls preferentially employed the Fas-FasL mechanism. Mtb-induced CD8+ CTL effector cells from patients used the perforin-based mechanism while cells from N controls also used the Fas-FasL pathway. While Mtb-induced γδ CTL from patients and PPD–N employed the latter mechanism cells from PPD+N individuals also used the perforin pathway. It can be concluded that shifts in the CTL response and the cytolytic mechanisms take place as the pulmonary involvement becomes more severe. PMID:12780692

  1. Fluoroquinolone interactions with Mycobacterium tuberculosis gyrase: Enhancing drug activity against wild-type and resistant gyrase.

    PubMed

    Aldred, Katie J; Blower, Tim R; Kerns, Robert J; Berger, James M; Osheroff, Neil

    2016-02-16

    Mycobacterium tuberculosis is a significant source of global morbidity and mortality. Moxifloxacin and other fluoroquinolones are important therapeutic agents for the treatment of tuberculosis, particularly multidrug-resistant infections. To guide the development of new quinolone-based agents, it is critical to understand the basis of drug action against M. tuberculosis gyrase and how mutations in the enzyme cause resistance. Therefore, we characterized interactions of fluoroquinolones and related drugs with WT gyrase and enzymes carrying mutations at GyrA(A90) and GyrA(D94). M. tuberculosis gyrase lacks a conserved serine that anchors a water-metal ion bridge that is critical for quinolone interactions with other bacterial type II topoisomerases. Despite the fact that the serine is replaced by an alanine (i.e., GyrA(A90)) in M. tuberculosis gyrase, the bridge still forms and plays a functional role in mediating quinolone-gyrase interactions. Clinically relevant mutations at GyrA(A90) and GyrA(D94) cause quinolone resistance by disrupting the bridge-enzyme interaction, thereby decreasing drug affinity. Fluoroquinolone activity against WT and resistant enzymes is enhanced by the introduction of specific groups at the C7 and C8 positions. By dissecting fluoroquinolone-enzyme interactions, we determined that an 8-methyl-moxifloxacin derivative induces high levels of stable cleavage complexes with WT gyrase and two common resistant enzymes, GyrA(A90V) and GyrA(D94G). 8-Methyl-moxifloxacin was more potent than moxifloxacin against WT M. tuberculosis gyrase and displayed higher activity against the mutant enzymes than moxifloxacin did against WT gyrase. This chemical biology approach to defining drug-enzyme interactions has the potential to identify novel drugs with improved activity against tuberculosis.

  2. Fluoroquinolone interactions with Mycobacterium tuberculosis gyrase: Enhancing drug activity against wild-type and resistant gyrase

    PubMed Central

    Aldred, Katie J.; Kerns, Robert J.; Berger, James M.; Osheroff, Neil

    2016-01-01

    Mycobacterium tuberculosis is a significant source of global morbidity and mortality. Moxifloxacin and other fluoroquinolones are important therapeutic agents for the treatment of tuberculosis, particularly multidrug-resistant infections. To guide the development of new quinolone-based agents, it is critical to understand the basis of drug action against M. tuberculosis gyrase and how mutations in the enzyme cause resistance. Therefore, we characterized interactions of fluoroquinolones and related drugs with WT gyrase and enzymes carrying mutations at GyrAA90 and GyrAD94. M. tuberculosis gyrase lacks a conserved serine that anchors a water–metal ion bridge that is critical for quinolone interactions with other bacterial type II topoisomerases. Despite the fact that the serine is replaced by an alanine (i.e., GyrAA90) in M. tuberculosis gyrase, the bridge still forms and plays a functional role in mediating quinolone–gyrase interactions. Clinically relevant mutations at GyrAA90 and GyrAD94 cause quinolone resistance by disrupting the bridge–enzyme interaction, thereby decreasing drug affinity. Fluoroquinolone activity against WT and resistant enzymes is enhanced by the introduction of specific groups at the C7 and C8 positions. By dissecting fluoroquinolone–enzyme interactions, we determined that an 8-methyl-moxifloxacin derivative induces high levels of stable cleavage complexes with WT gyrase and two common resistant enzymes, GyrAA90V and GyrAD94G. 8-Methyl-moxifloxacin was more potent than moxifloxacin against WT M. tuberculosis gyrase and displayed higher activity against the mutant enzymes than moxifloxacin did against WT gyrase. This chemical biology approach to defining drug–enzyme interactions has the potential to identify novel drugs with improved activity against tuberculosis. PMID:26792518

  3. Evaluation of heat shock proteins for discriminating between latent tuberculosis infection and active tuberculosis: A preliminary report.

    PubMed

    Shekhawat, Seema D; Purohit, Hemant J; Taori, Girdhar M; Daginawala, Hatim F; Kashyap, Rajpal S

    2016-01-01

    The diagnosis of a latent tuberculosis infection (LTBI) is of the utmost concern. The available tests, the tuberculin skin test (TST) and the Quantiferon-TB Gold test (QFT-G) cannot discriminate between active TB and LTBI. Therefore, the aim of the study is to identify new biomarkers that can discriminate between active TB and LTBI and can also assess the risk of the individual developing active TB. In total, 55 blood samples were collected, of which 10 samples were from the active TB infection group, 10 were from the high-risk exposure group, 23 were from the low-risk exposure group, and 12 were from healthy controls living in a non-TB endemic area. A panel of heat shock proteins (Hsps), including host Hsp25, Hsp60, Hsp70, and Hsp90 and Mycobacterium tuberculosis (MTB) Hsp16, were evaluated in all of the collected samples using ELISA. The levels of the host Hsp(s) (Hsp25, Hsp60, Hsp70 and Hsp90) and MTB Hsp16 were significantly (p<0.05) elevated in the active TB group compared to the high-risk exposure group, the low-risk exposure group and the control group. Notably, the levels of the same panel of Hsp(s) were elevated in the high-risk exposure group compared to the low-risk exposure group. On follow-up, out of the 10 high-risk exposure participants, 3 converted into active TB, indicating that this group has the highest risk of developing TB. Thus, the evaluated panel of Hsp(s) can discriminate between LTBI and active TB. They can also identify individuals who are at the highest risk of developing active TB. Because they can be rapidly detected, Hsp(s) have an edge over the existing diagnostic tools for LTBI. The evaluation of these proteins will be useful in designing better diagnostic methods for LTBI.

  4. Cost–effectiveness of screening for active cases of tuberculosis in Flanders, Belgium

    PubMed Central

    Smit, G Suzanne A; Apers, Ludwig; Arrazola de Onate, Wouter; Beutels, Philippe; Dorny, Pierre; Forier, An-Marie; Janssens, Kristien; Macq, Jean; Mak, Ruud; Schol, Sandrina; Wildemeersch, Dirk; Speybroeck, Niko

    2017-01-01

    Abstract Objective To assess the cost–effectiveness of the tuberculosis screening activities currently funded by the Flemish government in Flanders, Belgium. Methods After estimating the expenses for 2013–2014 of each of nine screening components – which include high-risk groups, contacts and people who are seeking tuberculosis consultation at a centre for respiratory health care – and the associated costs per active case of tuberculosis identified between 2007 and 2014, we compared the cost–effectiveness of each component. The applied perspective was that of the Flemish government. Findings The three most cost-effective activities appeared to be the follow-up of asylum seekers who were found to have abnormal X-rays in initial screening at the Immigration Office, systematic screening in prisons and contact investigation. The mean costs of these activities were 5564 (95% uncertainty interval, UI: 3791–8160), 11 603 (95% UI: 9010–14 909) and 13 941 (95% UI: 10 723–18 201) euros (€) per detected active case, respectively. The periodic or supplementary initial screening of asylum seekers and the screening of new immigrants from high-incidence countries – which had corresponding costs of €51 813 (95% UI: 34 855–76 847), €126 236 (95% UI: 41 984–347 822) and €418 359 (95% UI: 74 975–1 686 588) – appeared much less cost-effective. Between 2007 and 2014, no active tuberculosis cases were detected during screening in the juvenile detention centres. Conclusion In Flanders, tuberculosis screening in juvenile detention centres and among new immigrants and the periodic or supplementary initial screening of asylum seekers appear to be relatively expensive ways of detecting people with active tuberculosis. PMID:28053362

  5. Early and Extended Early Bactericidal Activity of Linezolid in Pulmonary Tuberculosis

    PubMed Central

    Dietze, Reynaldo; Hadad, David Jamil; McGee, Bryan; Molino, Lucilia Pereira Dutra; Maciel, Ethel Leonor Noia; Peloquin, Charles A.; Johnson, Denise F.; Debanne, Sara M.; Eisenach, Kathleen; Boom, W. Henry; Palaci, Moises; Johnson, John L.

    2008-01-01

    Rationale: Linezolid, the first oxazolidinone approved for clinical use, has effective in vitro and promising in vivo activity against Mycobacterium tuberculosis. Objectives: To evaluate the early and extended early bactericidal activity of linezolid in patients with pulmonary tuberculosis. Methods: Randomized open label trial. Thirty patients with newly diagnosed smear-positive pulmonary tuberculosis (10 per arm) were assigned to receive isoniazid (300 mg daily) and linezolid (600 mg twice daily or 600 mg once daily) for 7 days. Sputum for quantitative culture was collected for 2 days before and then daily during 7 days of study drug administration. Bactericidal activity was estimated by measuring the decline in bacilli during the first 2 days (early bactericidal activity) and the last 5 days of study drug administration (extended early bactericidal activity). Measurements and Main Results: The mean early bactericidal activity of isoniazid (0.67 log10 cfu/ml/d) was greater than that of linezolid twice and once daily (0.26 and 0.18 log10 cfu/ml/d, respectively). The extended early bactericidal activity of linezolid between Days 2 and 7 was minimal. Conclusions: Linezolid has modest early bactericidal activity against rapidly dividing tubercle bacilli in patients with cavitary pulmonary tuberculosis during the first 2 days of administration, but little extended early bactericidal activity. Clinical trial registered with www.clinicaltrials.gov (NCT00396084). PMID:18787216

  6. Comparative Proteomics of Activated THP-1 Cells Infected with Mycobacterium tuberculosis Identifies Putative Clearance Biomarkers for Tuberculosis Treatment.

    PubMed

    Kaewseekhao, Benjawan; Naranbhai, Vivek; Roytrakul, Sittiruk; Namwat, Wises; Paemanee, Atchara; Lulitanond, Viraphong; Chaiprasert, Angkana; Faksri, Kiatichai

    2015-01-01

    Biomarkers for determining clearance of Mycobacterium tuberculosis (Mtb) infection during anti-tuberculosis therapy or following exposure could facilitate enhanced monitoring and treatment. We screened for biomarkers indicating clearance of Mtb infection in vitro. A comparative proteomic analysis was performed using GeLC MSI/MS. Intracellular and secreted proteomes from activated THP-1 cells infected with the Mtb H37Rv strain (MOI = 1) and treated with isoniazid and rifampicin for 1 day (infection stage) and 5 days (clearance stage) were analyzed. Host proteins associated with early infection (n = 82), clearance (n = 121), sustained in both conditions (n = 34) and suppressed by infection (n = 46) were elucidated. Of the potential clearance markers, SSFA2 and CAECAM18 showed the highest and lowest protein intensities, respectively. A western blot of CAECAM18 validated the LC MS/MS result. For three clearance markers (SSFA2, PARP14 and PSME4), in vivo clinical validation was concordantly reported in previous patient cohorts. A network analysis revealed that clearance markers were enriched amongst four protein interaction networks centered on: (i) CD44/CCND1, (ii) IFN-β1/NF-κB, (iii) TP53/TGF-β and (iv) IFN-γ/CCL2. After infection, proteins associated with proliferation, and recruitment of immune cells appeared to be enriched possibly reflecting recruitment of defense mechanisms. Counteracting proteins (CASP3 vs. Akt and NF-κB vs. TP53) associated with apoptosis regulation and its networks were enriched among the early and sustained infection biomarkers, indicating host-pathogen competition. The BRCA1/2 network was suppressed during infection, suggesting that cell proliferation suppression is a feature of Mtb survival. Our study provides insights into the mechanisms of host-Mtb interaction by comparing the stages of infection clearance. The identified clearance biomarkers may be useful in monitoring tuberculosis treatment.

  7. Auxiliary diagnostic value of monocyte chemoattractant protein-1 of whole blood in active tuberculosis

    PubMed Central

    Wang, Ying; Li, Hang; Bao, Hong; Jin, Yufen; Liu, Xiaoju; Wu, Xueqiong; Yu, Ting

    2015-01-01

    The aim of this study was to study the expression level of interferon-γ (IFN-γ) and monocyte chemoattractant protein-1 (MCP-1) in peripheral blood and its auxiliary diagnostic value in active tuberculosis. A chemiluminescence enzyme immunoassay method was used to detect the levels of IFN-γ and MCP-1 in peripheral blood. Then the receiver operating characteristic curve were drawn to determine the threshold of IFN-γ and MCP-1 for diagnosis of active tuberculosis and to evaluate their diagnostic performance. The specific IFN-γ and MCP-1 levels in the active tuberculosis group were significantly higher than those in the non-tuberculous pulmonary disease group (P < 0.01) and those in the healthy control group (P < 0.01). The IFN-γ levels in the healthy control group and the non-tuberculous respiratory disease group showed no statistically significant difference (P > 0.05), but the MCP-1 levels in the non-tuberculous respiratory disease group were significantly higher than those of the healthy control group (P < 0.05). The specific IFN-γ and MCP-1 level cut off values were 256 pg/ml and 389 pg/ml as an active tuberculosis diagnostic standard. The sensitivities of IFN-γ and MCP-1 were 57.3% and 92.8%, respectively; specificities were 80% and 80.7%, respectively; the positive predictive values were 76.9% and 84.9%, respectively; negative predictive values were 61.7% and 78.7%, respectively; and accuracy rates were 76.9% and 84.9%, respectively. Compared with the detection of IFN-γ, we observed a better diagnostic performance of MCP-1 in peripheral blood in active tuberculosis. MCP-1 may become one of the active tuberculosis auxiliary diagnostic targets. PMID:26309608

  8. Killing of virulent Mycobacterium tuberculosis by reactive nitrogen intermediates produced by activated murine macrophages

    PubMed Central

    1992-01-01

    Tuberculosis remains one of the major infectious causes of morbidity and mortality in the world, yet the mechanisms by which macrophages defend against Mycobacterium tuberculosis have remained obscure. Results from this study show that murine macrophages, activated by interferon gamma, and lipopolysaccharide or tumor necrosis factor alpha, both growth inhibit and kill M. tuberculosis. This antimycobacterial effect, demonstrable both in murine macrophage cell lines and in peritoneal macrophages of BALB/c mice, is independent of the macrophage capacity to generate reactive oxygen intermediates (ROI). Both the ROI-deficient murine macrophage cell line D9, and its ROI-generating, parental line J774.16, expressed comparable antimycobacterial activity upon activation. In addition, the oxygen radical scavengers superoxide dismutase (SOD), catalase, mannitol, and diazabicyclooctane had no effect on the antimycobacterial activity of macrophages. These findings, together with the results showing the relative resistance of M. tuberculosis to enzymatically generated H2O2, suggest that ROI are unlikely to be significantly involved in killing M. tuberculosis. In contrast, the antimycobacterial activity of these macrophages strongly correlates with the induction of the L-arginine- dependent generation of reactive nitrogen intermediates (RNI). The effector molecule(s) that could participate in mediating this antimycobacterial function are toxic RNI, including NO, NO2, and HNO2, as demonstrated by the mycobacteriocidal effect of acidified NO2. The oxygen radical scavenger SOD adventitiously perturbs RNI production, and cannot be used to discriminate between cytocidal mechanisms involving ROI and RNI. Overall, our results provide support for the view that the L-arginine-dependent production of RNI is the principal effector mechanism in activated murine macrophages responsible for killing and growth inhibiting virulent M. tuberculosis. PMID:1552282

  9. Rapid, Semiquantitative Assay To Discriminate among Compounds with Activity against Replicating or Nonreplicating Mycobacterium tuberculosis

    PubMed Central

    Roberts, Julia; Ling, Yan; Quezada, Landys Lopez; Glasheen, Jou; Ballinger, Elaine; Somersan-Karakaya, Selin; Warrier, Thulasi; Warren, J. David; Nathan, Carl

    2015-01-01

    The search for drugs that can kill replicating and nonreplicating Mycobacterium tuberculosis faces practical bottlenecks. Measurement of CFU and discrimination of bacteriostatic from bactericidal activity are costly in compounds, supplies, labor, and time. Testing compounds against M. tuberculosis under conditions that prevent the replication of M. tuberculosis often involves a second phase of the test in which conditions are altered to permit the replication of bacteria that survived the first phase. False-positive determinations of activity against nonreplicating M. tuberculosis may arise from carryover of compounds from the nonreplicating stage of the assay that act in the replicating stage. We mitigate these problems by carrying out a 96-well microplate liquid MIC assay and then transferring an aliquot of each well to a second set of plates in which each well contains agar supplemented with activated charcoal. After 7 to 10 days—about 2 weeks sooner than required to count CFU—fluorometry reveals whether M. tuberculosis bacilli in each well have replicated extensively enough to reduce a resazurin dye added for the final hour. This charcoal agar resazurin assay (CARA) distinguishes between bacterial biomasses in any two wells that differ by 2 to 3 log10 CFU. The CARA thus serves as a pretest and semiquantitative surrogate for longer, more laborious, and expensive CFU-based assays, helps distinguish bactericidal from bacteriostatic activity, and identifies compounds that are active under replicating conditions, nonreplicating conditions, or both. Results for 14 antimycobacterial compounds, including tuberculosis (TB) drugs, revealed that PA-824 (pretomanid) and TMC207 (bedaquiline) are largely bacteriostatic. PMID:26239979

  10. Anti-Mycobacterium tuberculosis activity and cytotoxicity of Calophyllum brasiliense Cambess (Clusiaceae)

    PubMed Central

    Pires, Claudia Terencio Agostinho; Brenzan, Mislaine Adriana; Scodro, Regiane Bertin de Lima; Cortez, Diógenes Aparício Garcia; Lopes, Luciana Dias Ghiraldi; Siqueira, Vera Lucia Dias; Cardoso, Rosilene Fressatti

    2014-01-01

    We evaluated the in vitro anti-Mycobacterium tuberculosis activity and the cytotoxicity of dichloromethane extract and pure compounds from the leaves of Calophyllum brasiliense. Purification of the dichloromethane extract yielded the pure compounds (-) mammea A/BB (1), (-) mammea B/BB (2) and amentoflavone (3). The compound structures were elucidated on the basis of spectroscopic and spectrometric data. The contents of bioactive compounds in the extracts were quantified using high performance liquid chromatography coupled to an ultraviolet detector. The anti-M. tuberculosis activity of the extracts and the pure compounds was evaluated using a resazurin microtitre assay plate. The cytotoxicity assay was performed in J774G.8 macrophages using the 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide colourimetric method. The quantification of the dichloromethane extract showed (1) and (2) at concentrations of 31.86 ± 2.6 and 8.24 ± 1.1 µg/mg of extract, respectively. The dichloromethane and aqueous extracts showed anti-M. tuberculosis H37Rv activity of 62.5 and 125 µg/mL, respectively. Coumarins (1) and (2) showed minimal inhibitory concentration ranges of 31.2 and 62.5 µg/mL against M. tuberculosis H37Rv and clinical isolates. Compound (3) showed no activity against M. tuberculosis H37Rv. The selectivity index ranged from 0.59-1.06. We report the activity of the extracts and coumarins from the leaves of C. brasiliense against M. tuberculosis. PMID:24676652

  11. Anti-Mycobacterium tuberculosis activity and cytotoxicity of Calophyllum brasiliense Cambess (Clusiaceae).

    PubMed

    Pires, Claudia Terencio Agostinho; Brenzan, Mislaine Adriana; Scodro, Regiane Bertin de Lima; Cortez, Diógenes Aparício Garcia; Lopes, Luciana Dias Ghiraldi; Siqueira, Vera Lucia Dias; Cardoso, Rosilene Fressatti

    2014-06-01

    We evaluated the in vitro anti-Mycobacterium tuberculosis activity and the cytotoxicity of dichloromethane extract and pure compounds from the leaves of Calophyllum brasiliense. Purification of the dichloromethane extract yielded the pure compounds (-) mammea A/BB (1), (-) mammea B/BB (2) and amentoflavone (3). The compound structures were elucidated on the basis of spectroscopic and spectrometric data. The contents of bioactive compounds in the extracts were quantified using high performance liquid chromatography coupled to an ultraviolet detector. The anti-M. tuberculosis activity of the extracts and the pure compounds was evaluated using a resazurin microtitre assay plate. The cytotoxicity assay was performed in J774G.8 macrophages using the 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide colourimetric method. The quantification of the dichloromethane extract showed (1) and (2) at concentrations of 31.86 ± 2.6 and 8.24 ± 1.1 µg/mg of extract, respectively. The dichloromethane and aqueous extracts showed anti-M. tuberculosis H37Rv activity of 62.5 and 125 µg/mL, respectively. Coumarins (1) and (2) showed minimal inhibitory concentration ranges of 31.2 and 62.5 µg/mL against M. tuberculosis H37Rv and clinical isolates. Compound (3) showed no activity against M. tuberculosis H37Rv. The selectivity index ranged from 0.59-1.06. We report the activity of the extracts and coumarins from the leaves of C. brasiliense against M. tuberculosis.

  12. Fc gamma receptors regulate immune activation and susceptibility during Mycobacterium tuberculosis infection.

    PubMed

    Maglione, Paul J; Xu, Jiayong; Casadevall, Arturo; Chan, John

    2008-03-01

    The critical role of cellular immunity during tuberculosis (TB) has been extensively studied, but the impact of Abs upon this infection remains poorly defined. Previously, we demonstrated that B cells are required for optimal protection in Mycobacterium tuberculosis-infected mice. FcgammaR modulate immunity by engaging Igs produced by B cells. We report that C57BL/6 mice deficient in inhibitory FcgammaRIIB (RIIB-/-) manifested enhanced mycobacterial containment and diminished immunopathology compared with wild-type controls. These findings corresponded with enhanced pulmonary Th1 responses, evidenced by increased IFN-gamma-producing CD4+ T cells, and elevated expression of MHC class II and costimulatory molecules B7-1 and B7-2 in the lungs. Upon M. tuberculosis infection and immune complex engagement, RIIB-/- macrophages produced more of the p40 component of the Th1-promoting cytokine IL-12. These data strongly suggest that FcgammaRIIB engagement can dampen the TB Th1 response by attenuating IL-12p40 production or activation of APCs. Conversely, C57BL/6 mice lacking the gamma-chain shared by activating FcgammaR had enhanced susceptibility and exacerbated immunopathology upon M. tuberculosis challenge, associated with increased production of the immunosuppressive cytokine IL-10. Thus, engagement of distinct FcgammaR can divergently affect cytokine production and susceptibility during M. tuberculosis infection.

  13. Stress and host immunity amplify Mycobacterium tuberculosis phenotypic heterogeneity and induce nongrowing metabolically active forms.

    PubMed

    Manina, Giulia; Dhar, Neeraj; McKinney, John D

    2015-01-14

    Nonreplicating and metabolically quiescent bacteria are implicated in latent tuberculosis infections and relapses following "sterilizing" chemotherapy. However, evidence linking bacterial dormancy and persistence in vivo is largely inconclusive. Here we measure the single-cell dynamics of Mycobacterium tuberculosis replication and ribosomal activity using quantitative time-lapse microscopy and a reporter of ribosomal RNA gene expression. Single-cell dynamics exhibit heterogeneity under standard growth conditions, which is amplified by stressful conditions such as nutrient limitation, stationary phase, intracellular replication, and growth in mouse lungs. Additionally, the lungs of chronically infected mice harbor a subpopulation of nongrowing but metabolically active bacteria, which are absent in mice lacking interferon-γ, a cytokine essential for antituberculosis immunity. These cryptic bacterial forms are prominent in mice treated with the antituberculosis drug isoniazid, suggesting a role in postchemotherapeutic relapses. Thus, amplification of bacterial phenotypic heterogeneity in response to host immunity and drug pressure may contribute to tuberculosis persistence.

  14. Activity against drug resistant-tuberculosis strains of plants used in Mexican traditional medicine to treat tuberculosis and other respiratory diseases.

    PubMed

    Camacho-Corona, María Del Rayo; Ramírez-Cabrera, Mónica A; Santiago, Omar González-; Garza-González, Elvira; Palacios, Isidoro de Paz; Luna-Herrera, Julieta

    2008-01-01

    Tuberculosis (TB) kills about 3 million people per year worldwide. Furthermore, TB is an infectious disease associated with HIV patients, and there is a rise in multidrug-resistant TB (MDR-TB) cases around the world. There is a need for new anti-TB agents. The study evaluated the antimycobacterial activity of nine plants used in Mexican traditional medicine to treat tuberculosis and other respiratory diseases. Nasturtium officinale showed the best activity (MIC = 100 microg/mL) against the sensitive Mycobacterium tuberculosis. The following plants were active also but at 200 microg/mL: Citrus sinensis, Citrus aurantifolia, Foeniculum vulgare, Larrea tridentata, Musa acuminata and Olea europaea. Contrary to the above data, activity against drug-resistant variants of M. tuberculosis was more evident, e.g. N. officinale was the most potent (MIC < or = 100 microg/mL) against the four mono-resistant variants tested; F. vulgare and O. europaea were active against all the resistant variants (MICs < or = 100 microg/mL). The most susceptible variant was the isoniazid resistant, being inhibited by C. aurantifolia, C. sinensis and O. europaea (MIC = 25 microg/mL). These data point to the importance of biological testing of extracts against drug-resistant M. tuberculosis isolates, and the bioguided assay of these extracts for the identification of lead compounds against MDR-TB isolates.

  15. Latent Tuberculosis in Health Care Workers Exposed to Active Tuberculosis in a Tertiary Care Hospital in Oman

    PubMed Central

    Khamis, Faryal; Al-Lawati, Adil; Al-Zakwani, Ibrahim; Al-Abri, Seif; Al-Naamani, Jaleelah; Al-Harthi, Harith; Al-Jardani, Amina; Al-Harthi, Aliya

    2016-01-01

    Objectives Data on the prevalence of tuberculosis (TB) in healthcare workers (HCW) in Oman and the Arabian Gulf is scarce. The aim of this study was to estimate the prevalence of latent tuberculosis (LTB) among HCW exposed to active TB in one of the tertiary care hospitals in Muscat. Methods Exposed HCW were screened for LTB from January to June 2012 using skin tuberculin and serum interferon tests. Candidates were followed-up for a total of nine months. Descriptive statistics were used to summarize the data. Results A total of 371 exposed HCW were involved in the study. The incidence of LTB in exposed HCW was 33.2% (n = 123). Almost 54% (66/123) of the HCW started treatment and only 42.4% (28/66) completed the full nine-month treatment course. Conclusions The high prevalence of LTBI in exposed HCW merits further evaluation of the screening and treatment programs in the country. Future countrywide studies are warranted to provide more precise statistics on the prevalence and management of this public health issue. PMID:27403243

  16. Circulating B-lymphocytes as potential biomarkers of tuberculosis infection activity.

    PubMed

    Sebina, Ismail; Biraro, Irene A; Dockrell, Hazel M; Elliott, Alison M; Cose, Stephen

    2014-01-01

    Accurate biomarkers of Mycobacterium tuberculosis infection activity would significantly improve early diagnosis, treatment and management of M. tuberculosis infection. We hypothesised that circulating B-lymphocytes may be useful biomarkers of tuberculosis (TB) infection status in highly TB-endemic settings. Ex-vivo and in-vitro mycobacteria-specific B-cell ELISPOT assays were used to examine the plasmablast (PB) and memory B-cell (MBC) responses in the peripheral blood of adult, healthy, community controls (n = 151) and of active TB patients (n = 48) living in Uganda. Frequencies of mycobacteria-specific PBs were markedly higher in active TB patients compared to healthy controls, and, conversely, MBCs were markedly higher in the healthy controls compared to active TB patients. In addition, the community controls with evidence of latent TB infection had higher peripheral blood PB and MBC responses than those without evidence of TB infection. These data demonstrate that peripheral blood B-cell responses are differentially modulated during latent and active M. tuberculosis infection, and suggest that the PB to MBC ratio may be a useful biomarker of TB infection activity.

  17. 77 FR 16126 - Microbiology Devices; Reclassification of Nucleic Acid-Based Systems for Mycobacterium tuberculosis

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-19

    ... and control materials with the possibility of transmission of tuberculosis infection to healthcare... materials with the possibility of transmission of tuberculosis infection to healthcare workers could be... of rapid detection of infection in patients with suspected tuberculosis as compared to...

  18. An adenosine triphosphate-independent proteasome activator contributes to the virulence of Mycobacterium tuberculosis.

    PubMed

    Jastrab, Jordan B; Wang, Tong; Murphy, J Patrick; Bai, Lin; Hu, Kuan; Merkx, Remco; Huang, Jessica; Chatterjee, Champak; Ovaa, Huib; Gygi, Steven P; Li, Huilin; Darwin, K Heran

    2015-04-07

    Mycobacterium tuberculosis encodes a proteasome that is highly similar to eukaryotic proteasomes and is required to cause lethal infections in animals. The only pathway known to target proteins for proteasomal degradation in bacteria is pupylation, which is functionally analogous to eukaryotic ubiquitylation. However, evidence suggests that the M. tuberculosis proteasome contributes to pupylation-independent pathways as well. To identify new proteasome cofactors that might contribute to such pathways, we isolated proteins that bound to proteasomes overproduced in M. tuberculosis and found a previously uncharacterized protein, Rv3780, which formed rings and capped M. tuberculosis proteasome core particles. Rv3780 enhanced peptide and protein degradation by proteasomes in an adenosine triphosphate (ATP)-independent manner. We identified putative Rv3780-dependent proteasome substrates and found that Rv3780 promoted robust degradation of the heat shock protein repressor, HspR. Importantly, an M. tuberculosis Rv3780 mutant had a general growth defect, was sensitive to heat stress, and was attenuated for growth in mice. Collectively, these data demonstrate that ATP-independent proteasome activators are not confined to eukaryotes and can contribute to the virulence of one the world's most devastating pathogens.

  19. An adenosine triphosphate-independent proteasome activator contributes to the virulence of Mycobacterium tuberculosis

    SciTech Connect

    Jastrab, Jordan B.; Wang, Tong; Murphy, J. Patrick; Bai, Lin; Hu, Kuan; Merkx, Remco; Huang, Jessica; Chatterjee, Champak; Ovaa, Huib; Gygi, Steven P.; Li, Huilin; Darwin, K. Heran

    2015-03-23

    Mycobacterium tuberculosis encodes a proteasome that is highly similar to eukaryotic proteasomes and is required to cause lethal infections in animals. The only pathway known to target proteins for proteasomal degradation in bacteria is pupylation, which is functionally analogous to eukaryotic ubiquitylation. However, evidence suggests that the M. tuberculosis proteasome contributes to pupylation-independent pathways as well. To identify new proteasome cofactors that might contribute to such pathways, we isolated proteins that bound to proteasomes overproduced in M. tuberculosis and found a previously uncharacterized protein, Rv3780, which formed rings and capped M. tuberculosis proteasome core particles. Rv3780 enhanced peptide and protein degradation by proteasomes in an adenosine triphosphate (ATP)-independent manner. We identified putative Rv3780-dependent proteasome substrates and found that Rv3780 promoted robust degradation of the heat shock protein repressor, HspR. Importantly, an M. tuberculosis Rv3780 mutant had a general growth defect, was sensitive to heat stress, and was attenuated for growth in mice. Collectively, these data demonstrate that ATP-independent proteasome activators are not confined to eukaryotes and can contribute to the virulence of one the world’s most devastating pathogens.

  20. An adenosine triphosphate-independent proteasome activator contributes to the virulence of Mycobacterium tuberculosis

    DOE PAGES

    Jastrab, Jordan B.; Wang, Tong; Murphy, J. Patrick; ...

    2015-03-23

    Mycobacterium tuberculosis encodes a proteasome that is highly similar to eukaryotic proteasomes and is required to cause lethal infections in animals. The only pathway known to target proteins for proteasomal degradation in bacteria is pupylation, which is functionally analogous to eukaryotic ubiquitylation. However, evidence suggests that the M. tuberculosis proteasome contributes to pupylation-independent pathways as well. To identify new proteasome cofactors that might contribute to such pathways, we isolated proteins that bound to proteasomes overproduced in M. tuberculosis and found a previously uncharacterized protein, Rv3780, which formed rings and capped M. tuberculosis proteasome core particles. Rv3780 enhanced peptide and proteinmore » degradation by proteasomes in an adenosine triphosphate (ATP)-independent manner. We identified putative Rv3780-dependent proteasome substrates and found that Rv3780 promoted robust degradation of the heat shock protein repressor, HspR. Importantly, an M. tuberculosis Rv3780 mutant had a general growth defect, was sensitive to heat stress, and was attenuated for growth in mice. Collectively, these data demonstrate that ATP-independent proteasome activators are not confined to eukaryotes and can contribute to the virulence of one the world’s most devastating pathogens.« less

  1. In Vitro Activity of a New Isothiazoloquinolone, ACH-702, against Mycobacterium tuberculosis and Other Mycobacteria▿

    PubMed Central

    Molina-Torres, Carmen A.; Ocampo-Candiani, Jorge; Rendón, Adrian; Pucci, Michael J.; Vera-Cabrera, Lucio

    2010-01-01

    In this work, we describe the activity of ACH-702 against clinical isolates of Mycobacterium tuberculosis and six different nontuberculous mycobacteria. The MIC50 and MIC90 of both susceptible and drug-resistant M. tuberculosis strains tested were 0.0625 and 0.125 μg/ml, respectively. The MIC50 and MIC90 values for Mycobacterium fortuitum isolates were 0.0625 μg/ml in both cases; Mycobacterium avium complex isolates showed MIC50 and MIC90 values of 0.25 and 4 μg/ml, respectively. PMID:20231398

  2. Intracellular activity of tedizolid phosphate and ACH-702 versus Mycobacterium tuberculosis infected macrophages

    PubMed Central

    2014-01-01

    Background Due to the emergency of multidrug-resistant strains of Mycobacterium tuberculosis, is necessary the evaluation of new compounds. Findings Tedizolid, a novel oxazolidinone, and ACH-702, a new isothiazoloquinolone, were tested against M. tuberculosis infected THP-1 macrophages. These two compounds significantly decreased the number of intracellular mycobacteria at 0.25X, 1X, 4X and 16X the MIC value. The drugs were tested either in nanoparticules or in free solution. Conclusion Tedizolid and ACH-702 have a good intracellular killing activity comparable to that of rifampin or moxifloxacin. PMID:24708819

  3. Modification of Rifamycin Polyketide Backbone Leads to Improved Drug Activity against Rifampicin-resistant Mycobacterium tuberculosis*

    PubMed Central

    Nigam, Aeshna; Almabruk, Khaled H.; Saxena, Anjali; Yang, Jongtae; Mukherjee, Udita; Kaur, Hardeep; Kohli, Puneet; Kumari, Rashmi; Singh, Priya; Zakharov, Lev N.; Singh, Yogendra; Mahmud, Taifo; Lal, Rup

    2014-01-01

    Rifamycin B, a product of Amycolatopsis mediterranei S699, is the precursor of clinically used antibiotics that are effective against tuberculosis, leprosy, and AIDS-related mycobacterial infections. However, prolonged usage of these antibiotics has resulted in the emergence of rifamycin-resistant strains of Mycobacterium tuberculosis. As part of our effort to generate better analogs of rifamycin, we substituted the acyltransferase domain of module 6 of rifamycin polyketide synthase with that of module 2 of rapamycin polyketide synthase. The resulting mutants (rifAT6::rapAT2) of A. mediterranei S699 produced new rifamycin analogs, 24-desmethylrifamycin B and 24-desmethylrifamycin SV, which contained modification in the polyketide backbone. 24-Desmethylrifamycin B was then converted to 24-desmethylrifamycin S, whose structure was confirmed by MS, NMR, and X-ray crystallography. Subsequently, 24-desmethylrifamycin S was converted to 24-desmethylrifampicin, which showed excellent antibacterial activity against several rifampicin-resistant M. tuberculosis strains. PMID:24923585

  4. Modification of rifamycin polyketide backbone leads to improved drug activity against rifampicin-resistant Mycobacterium tuberculosis.

    PubMed

    Nigam, Aeshna; Almabruk, Khaled H; Saxena, Anjali; Yang, Jongtae; Mukherjee, Udita; Kaur, Hardeep; Kohli, Puneet; Kumari, Rashmi; Singh, Priya; Zakharov, Lev N; Singh, Yogendra; Mahmud, Taifo; Lal, Rup

    2014-07-25

    Rifamycin B, a product of Amycolatopsis mediterranei S699, is the precursor of clinically used antibiotics that are effective against tuberculosis, leprosy, and AIDS-related mycobacterial infections. However, prolonged usage of these antibiotics has resulted in the emergence of rifamycin-resistant strains of Mycobacterium tuberculosis. As part of our effort to generate better analogs of rifamycin, we substituted the acyltransferase domain of module 6 of rifamycin polyketide synthase with that of module 2 of rapamycin polyketide synthase. The resulting mutants (rifAT6::rapAT2) of A. mediterranei S699 produced new rifamycin analogs, 24-desmethylrifamycin B and 24-desmethylrifamycin SV, which contained modification in the polyketide backbone. 24-Desmethylrifamycin B was then converted to 24-desmethylrifamycin S, whose structure was confirmed by MS, NMR, and X-ray crystallography. Subsequently, 24-desmethylrifamycin S was converted to 24-desmethylrifampicin, which showed excellent antibacterial activity against several rifampicin-resistant M. tuberculosis strains.

  5. Functional analysis of TPM domain containing Rv2345 of Mycobacterium tuberculosis identifies its phosphatase activity.

    PubMed

    Sinha, Avni; Eniyan, Kandasamy; Sinha, Swati; Lynn, Andrew Michael; Bajpai, Urmi

    2015-07-01

    Mycobacterium tuberculosis (Mtb) is the causal agent of tuberculosis, the second largest infectious disease. With the rise of multi-drug resistant strains of M. tuberculosis, serious challenge lies ahead of us in treating the disease. The availability of complete genome sequence of Mtb has improved the scope for identifying new proteins that would not only further our understanding of biology of the organism but could also serve to discover new drug targets. In this study, Rv2345, a hypothetical membrane protein of M. tuberculosis H37Rv, which is reported to be a putative ortholog of ZipA cell division protein has been assigned function through functional annotation using bioinformatics tools followed by experimental validation. Sequence analysis showed Rv2345 to have a TPM domain at its N-terminal region and predicted it to have phosphatase activity. The TPM domain containing region of Rv2345 was cloned and expressed using pET28a vector in Escherichia coli and purified by Nickel affinity chromatography. The purified TPM domain was tested in vitro and our results confirmed it to have phosphatase activity. The enzyme activity was first checked and optimized with pNPP as substrate, followed by using ATP, which was also found to be used as substrate by the purified protein. Hence sequence analysis followed by in vitro studies characterizes TPM domain of Rv2345 to contain phosphatase activity.

  6. Activation of JAK2/STAT1-alpha-dependent signaling events during Mycobacterium tuberculosis-induced macrophage apoptosis.

    PubMed

    Rojas, Mauricio; Olivier, Martin; García, Luis F

    2002-01-01

    Induction of apoptosis by Mycobacterium tuberculosis in murine macrophage involves TNF-alpha and nitric oxide (NO) production and caspase cascade activation; however, the intracellular signaling pathways implicated remain to be established. Our results indicate that infection of the B10R murine macrophage line with M. tuberculosis induces apoptosis independent of mycobacterial phagocytosis and that M. tuberculosis induces protein tyrosine kinase (PTK) activity, JAK2/STAT1-alpha phosphorylation, and STAT1-alpha nuclear translocation. Inhibitors of PTK (AG-126), or JAK2 (AG-490) inhibited TNF-alpha and NO production, caspase 1 activation and apoptosis, suggesting that M. tuberculosis-induction of these events depends on JAK2/STAT1-alpha activation. In addition, we have obtained evidence that ManLAM capacity to inhibit M. tuberculosis-induced apoptosis involves the activation of the PTP SHP-1. The finding that M. tuberculosis infection activate JAK2/STAT1-alpha pathway suggests that M. tuberculosis might mimic macrophage-activating stimuli.

  7. Enhancement of antibiotic activity by efflux inhibitors against multidrug resistant Mycobacterium tuberculosis clinical isolates from Brazil.

    PubMed

    Coelho, Tatiane; Machado, Diana; Couto, Isabel; Maschmann, Raquel; Ramos, Daniela; von Groll, Andrea; Rossetti, Maria L; Silva, Pedro A; Viveiros, Miguel

    2015-01-01

    Drug resistant tuberculosis continues to increase and new approaches for its treatment are necessary. The identification of M. tuberculosis clinical isolates presenting efflux as part of their resistant phenotype has a major impact in tuberculosis treatment. In this work, we used a checkerboard procedure combined with the tetrazolium microplate-based assay (TEMA) to study single combinations between antituberculosis drugs and efflux inhibitors (EIs) against multidrug resistant M. tuberculosis clinical isolates using the fully susceptible strain H37Rv as reference. Efflux activity was studied on a real-time basis by a fluorometric method that uses ethidium bromide as efflux substrate. Quantification of efflux pump genes mRNA transcriptional levels were performed by RT-qPCR. The fractional inhibitory concentrations (FIC) indicated synergistic activity for the interactions between isoniazid, rifampicin, amikacin, ofloxacin, and ethidium bromide plus the EIs verapamil, thioridazine and chlorpromazine. The FICs ranged from 0.25, indicating a four-fold reduction on the MICs, to 0.015, 64-fold reduction. The detection of active efflux by real-time fluorometry showed that all strains presented intrinsic efflux activity that contributes to the overall resistance which can be inhibited in the presence of the EIs. The quantification of the mRNA levels of the most important efflux pump genes on these strains shows that they are intrinsically predisposed to expel toxic compounds as the exposure to subinhibitory concentrations of antibiotics were not necessary to increase the pump mRNA levels when compared with the non-exposed counterpart. The results obtained in this study confirm that the intrinsic efflux activity contributes to the overall resistance in multidrug resistant clinical isolates of M. tuberculosis and that the inhibition of efflux pumps by the EIs can enhance the clinical effect of antibiotics that are their substrates.

  8. Clofazimine Contributes Sustained Antimicrobial Activity after Treatment Cessation in a Mouse Model of Tuberculosis Chemotherapy

    PubMed Central

    Swanson, Rosemary V.; Ammerman, Nicole C.; Ngcobo, Bongani; Adamson, John; Moodley, Chivonne; Dorasamy, Afton; Moodley, Sashen; Mgaga, Zinhle; Bester, Linda A.; Singh, Sanil D.; Almeida, Deepak V.

    2016-01-01

    Experimental and clinical studies have indicated that the antileprosy drug clofazimine may contribute treatment-shortening activity when included in tuberculosis treatment regimens. Clofazimine accumulates to high levels in tissues, has a long half-life, and remains in the body for months after administration is stopped. We hypothesized that in tuberculosis treatment, accumulated clofazimine may contribute sustained antimicrobial activity after treatment cessation, and we used the BALB/c mouse model of chronic tuberculosis chemotherapy to address this hypothesis. Mycobacterium tuberculosis-infected mice were treated for 4 weeks or 8 weeks with either isoniazid alone, clofazimine alone, the first-line regimen rifampin-isoniazid-pyrazinamide-ethambutol, or a first-line regimen where clofazimine was administered in place of ethambutol. To evaluate posttreatment antimicrobial activity, bacterial regrowth in the lungs and spleens was assessed at the day of treatment cessation and 2, 4, 6, and 8 weeks after treatment was stopped. Bacterial regrowth was delayed in all mice receiving clofazimine, either alone or in combination, compared to the mice that did not receive clofazimine. This effect was especially evident in mice receiving multidrug therapy. In mice not receiving clofazimine, bacterial regrowth began almost immediately after treatment was stopped, while in mice receiving clofazimine, bacterial regrowth was delayed for up to 6 weeks, with the duration of sustained antimicrobial activity being positively associated with the time that serum clofazimine levels remained at or above the 0.25-μg/ml MIC for M. tuberculosis. Thus, sustained activity of clofazimine may be important in the treatment-shortening effect associated with this drug. PMID:26926638

  9. [Primary infection and pulmonary tuberculosis].

    PubMed

    Toujani, S; Ben Salah, N; Cherif, J; Mjid, M; Ouahchy, Y; Zakhama, H; Daghfous, J; Beji, M; Mehiri-Ben Rhouma, N; Louzir, B

    2015-01-01

    Tuberculosis is a major public health problem worldwide. Indeed, a third of the world population is infected with Mycobacterium tuberculosis and more than 8 million new cases of tuberculosis each year. Pulmonary tuberculosis is the most common location. Its diagnosis is difficult and often established with a delay causing a spread of infection. The diagnosis of tuberculosis infection is mainly based on immunological tests represented by the tuberculin skin test and detection of gamma interferon, while the diagnosis of pulmonary tuberculosis is suspected on epidemiological context, lasting general and respiratory symptoms, contrasting usually with normal lung examination, and a chest radiography showing suggestive lesions. The radioclinical feature may be atypical in patients with extreme ages and in case of immunodeficiency. Confirmation of tuberculosis is bacteriological. Conventional bacteriological methods remain the reference. Innovative tests using the technique of molecular biology have improved the diagnosis of tuberculosis in terms of sensitivity and especially speed. However, those techniques are of limited use.

  10. Quantitative Comparison of Active and Latent Tuberculosis in the Cynomolgus Macaque Model▿ †

    PubMed Central

    Lin, Philana Ling; Rodgers, Mark; Smith, Le'kneitah; Bigbee, Matthew; Myers, Amy; Bigbee, Carolyn; Chiosea, Ion; Capuano, Saverio V.; Fuhrman, Carl; Klein, Edwin; Flynn, JoAnne L.

    2009-01-01

    We previously described that low-dose Mycobacterium tuberculosis infection in cynomolgus macaques results in a spectrum of disease similar to that of human infection: primary disease, latent infection, and reactivation tuberculosis (S. V. Capuano III, D. A. Croix, S. Pawar, A. Zinovik, A. Myers, P. L. Lin, S. Bissel, C. Fuhrman, E. Klein, and J. L. Flynn, Infect. Immun. 71:5831-5844, 2003). This is the only established model of latent infection, and it provides a unique opportunity to understand host and pathogen differences across of range of disease states. Here, we provide a more extensive and detailed characterization of the gross pathology, microscopic histopathology, and immunologic characteristics of monkeys in each clinical disease category. The data underscore the similarities between human and nonhuman primate M. tuberculosis infection. Furthermore, we describe novel methods of quantifying gross pathology and bacterial burden that distinguish between active disease and latent infection, and we extend the usefulness of this model for comparative studies. Early in infection, an abnormal chest X ray, M. tuberculosis growth by gastric aspirate, and increased mycobacterium-specific gamma interferon (IFN-γ) in peripheral blood mononuclear cells (PBMCs) and bronchoalveolar lavage (BAL) cells were associated with the development of active disease. At necropsy, disease was quantified with respect to pathology and bacterial numbers. Microscopically, a spectrum of granuloma types are seen and differ with disease type. At necropsy, monkeys with active disease had more lung T cells and more IFN-γ from PBMC, BAL, and mediastinal lymph nodes than monkeys with latent infection. Finally, we have observed a spectrum of disease not only in monkeys with active disease but also in those with latent infection that provides insight into human latent tuberculosis. PMID:19620341

  11. [Recommendations for the diagnosis and treatment of latent and active tuberculosis in patients with inflammatory joint diseases treated with tumour necrosis factor alpha inhibitors].

    PubMed

    Fonseca, João Eurico; Lucas, Helena; Canhão, Helena; Duarte, Raquel; Santos, Maria José; Villar, Miguel; Faustino, Augusto; Raymundo, Elena

    2006-01-01

    The Portuguese Society of Rheumatology (SPR) and the Portuguese Society of Pulmonology (SPP) have developed guidelines for the diagnosis and treatment of latent tuberculosis infection (LTBI) and active tuberculosis (AT) in patients with inflammatory joint diseases (IJD), namely rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis, treated with tumour necrosis factor alpha (TNF-alpha) antagonists. Due to the high risk of tuberculosis (TB) in patients with IJD, LTBI and AT screening should be performed as soon as possible, ideally at the moment of IJD diagnosis. Even if TB screening was performed at the beginning of the disease, the evaluation should be repeated before starting anti-TNF-alpha therapy. When TB (LTBI orAT) treatment is indicated, it should be performed before the beginning of anti-TNF-alpha therapy. If the IJD activity requires urgent anti-TNF-alpha therapy, these drugs can be started after two months of antituberculosis therapy in AT cases, or after one month in LTBI cases. Chest X-ray is mandatory for all patients. If abnormal, e.g. Gohn complex, the patient should be treated as LTBI; residual lesions require the exclusion of AT and patients with history of untreated or incomplete TB treatment should be treated as LTBI. In cases of suspected active lesions, AT diagnosis should be confirmed and adequate therapy initiated. Tuberculin skin test (TST), with two units of RT23, should be performed in all patients. If induration is less than 5 mm, the test should be repeated after 1 to 2 weeks, on the opposite forearm, and should be considered negative if the result is again inferior to 5 mm. Positive TST implicates LTBI treatment. IfTST is performed in immunosupressed IJD patients, LTBI treatment should be offered to the patient before starting anti-TNFalpha therapy, even in the presence of a negative test.

  12. Recommendations for the diagnosis and treatment of latent and active tuberculosis in inflammatory joint diseases candidates for therapy with tumor necrosis factor alpha inhibitors: March 2008 update.

    PubMed

    Fonseca, João Eurico; Lucas, Helena; Canhão, Helena; Duarte, Raquel; Santos, Maria José; Villar, Miguel; Faustino, Augusto; Raymundo, Elena

    2008-01-01

    The Portuguese Society of Rheumatology and the Portuguese Society of Pulmonology have updated the guidelines for the diagnosis and treatment of latent tuberculosis infection (LTBI) and active tuberculosis (ATB) in patients with inflammatory joint diseases (IJD) that are candidates to therapy with tumour necrosis factor alpha (TNFalpha) antagonists. In order to reduce the risk of tuberculosis (TB) reactivation and the incidence of new infections, TB screening is recommended to be done as soon as possible, ideally at the moment of IJD diagnosis, and patient assessment repeated before starting anti-TNFalpha therapy. Treatment for ATB and LTBI must be done under the care of a TB specialist. When TB treatment is indicated, it should be completed prior to starting anti-TNFalpha therapy. If the IJD activity justifies the need for immediate treatment, anti-TNFalpha therapy can be started two months after antituberculous therapy has been initiated, in the case of ATB, and one month after in the case of LTBI. Chest X-ray is mandatory for all patients. If Gohn s complex is present, the patient should be treated for LTBI; healed lesions require the exclusion of ATB. In cases of suspected active lesions ATB should be excluded/confirmed and adequate therapy initiated. Tuberculin skin test, with two units of RT23, should be performed in all patients. If the induration is <5 mm, the test should be repeated within 1 to 2 weeks, on the opposite forearm, and will be considered negative only if the result is again <5 mm. Positive TST implicates LTBI treatment, unless previous proper treatment was provided. If TST is performed in immunossuppressed IJD patients, LTBI treatment should be offered to the patient before starting anti-TNFalpha therapy, even in the presence of a negative test, after risk/benefit assessment.

  13. Recommendations for the diagnosis and treatment of latent and active tuberculosis in inflammatory joint diseases candidates for therapy with tumor necrosis factor alpha inhibitors - March 2008 update.

    PubMed

    Fonseca, João Eurico; Lucas, Helena; Canhão, Helena; Duarte, Raquel; Santos, Maria José; Villar, Miguel; Faustino, Augusto; Raymundo, Elena

    2008-01-01

    The Portuguese Society of Rheumatology and the Portuguese Society of Pulmonology have updated the guidelines for the diagnosis and treatment of latent tuberculosis infection (LTBI) and active tuberculosis (ATB) in patients with inflammatory joint diseases (IJD) that are candidates to therapy with tumour necrosis factor alpha (TNFα) antagonists. In order to reduce the risk of tuberculosis (TB) reactivation and the incidence of new infections, TB screening is recommended to be done as soon as possible, ideally at the moment of IJD diagnosis, and patient assessment repeated before starting anti-TNFα therapy. Treatment for ATB and LTBI must be done under the care of a TB specialist. When TB treatment is indicated, it should be completed prior to starting anti-TNFα therapy. If the IJD activity justifies the need for immediate treatment, anti-TNFα therapy can be started two months after antituberculous therapy has been initiated, in the case of ATB, and one month after in the case of LTBI. Chest X-ray is mandatory for all patients. If Gohn's complex is present, the patient should be treated for LTBI; healed lesions require the exclusion of ATB. In cases of suspected active lesions, ATB should be excluded/confirmed and adequate therapy initiated. Tuberculin skin test, with two units of RT23, should be performed in all patients. If the induration is <5 mm, the test should be repeated within 1 to 2 weeks, on the opposite forearm, and will be considered negative only if the result is again <5 mm. Positive TST implicates LTBI treatment, unless previous proper treatment was provided. If TST is performed in immunossuppressed IJD patients, LTBI treatment should be offered to the patient before starting anti-TNF-α therapy, even in the presence of a negative test, after risk / benefit assessment. Rev Port Pneumol 2007; XIV (2): 271-283.

  14. [Tuberculosis of the prostate].

    PubMed

    Streltsova, O S; Krupin, V N; Yunusova, K E; Mamonov, M V

    2016-12-01

    Genitourinary tract is the second most common site where extrapulmonary tuberculosis (TB) occurs. Genitourinary TB is notable for a latent clinical course and difficult diagnosis. The paper presents clinical observations of two patients treated in a urology department of a general public hospital. One of them was diagnosed with tuberculosis of the prostate, MTB+. In the other, TB of the prostate was suspected based on pathologic assessment of the surgical specimen after surgery for prostate cancer.

  15. Extrapulmonary tuberculosis: tuberculous meningitis new developments.

    PubMed

    Galimi, R

    2011-04-01

    started promptly in all patients in whom the diagnosis of TBM is suspected. Corticosteroids reduce the number of deaths. Development of an effective vaccine against tuberculosis hinges on an improved understanding of the human immune response to Mycobacterium tuberculosis (Mtb). The emergence of drug resistant tuberculosis poses a serious threat to the control of this pathogen, and the development of drugs that are active against the resistant strains is vital. Further research into the epidemiology, immune mechanisms, diagnosis, treatment, and prevention of TBM is urgently needed.

  16. Tuberculosis and Diabetes

    MedlinePlus

    TUBERCULOSIS www.who.int/tb & DIABETES THE DUAL EPIDEMIC OF TB AND DIABETES DEADLY LINKAGES  People with ... higher risk of progressing from latent to active tuberculosis.  Diabetes triples a person’s risk of developing TB. ...

  17. Target Prediction for an Open Access Set of Compounds Active against Mycobacterium tuberculosis

    PubMed Central

    Martínez-Jiménez, Francisco; Papadatos, George; Yang, Lun; Wallace, Iain M.; Kumar, Vinod; Pieper, Ursula; Sali, Andrej; Brown, James R.; Overington, John P.; Marti-Renom, Marc A.

    2013-01-01

    Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), infects an estimated two billion people worldwide and is the leading cause of mortality due to infectious disease. The development of new anti-TB therapeutics is required, because of the emergence of multi-drug resistance strains as well as co-infection with other pathogens, especially HIV. Recently, the pharmaceutical company GlaxoSmithKline published the results of a high-throughput screen (HTS) of their two million compound library for anti-mycobacterial phenotypes. The screen revealed 776 compounds with significant activity against the M. tuberculosis H37Rv strain, including a subset of 177 prioritized compounds with high potency and low in vitro cytotoxicity. The next major challenge is the identification of the target proteins. Here, we use a computational approach that integrates historical bioassay data, chemical properties and structural comparisons of selected compounds to propose their potential targets in M. tuberculosis. We predicted 139 target - compound links, providing a necessary basis for further studies to characterize the mode of action of these compounds. The results from our analysis, including the predicted structural models, are available to the wider scientific community in the open source mode, to encourage further development of novel TB therapeutics. PMID:24098102

  18. Activity against multidrug-resistant Mycobacterium tuberculosis in Mexican plants used to treat respiratory diseases.

    PubMed

    Jimenez-Arellanes, Adelina; Meckes, Mariana; Ramirez, Raquel; Torres, Javier; Luna-Herrera, Julieta

    2003-09-01

    The increase of multidrug-resistant Mycobacterium tuberculosis (MDR-TB) demands the search for alternative antimycobacterial drugs. The aim of this study was to evaluate plants used in Mexican traditional medicine to treat respiratory diseases for activity against MDR-TB. A group of 22 plants was screened for activity against Mycobacterium tuberculosis H37Rv and Mycobacterium avium at concentrations from 50 to 200 microg/mL. The antimycobacterial effect was determined by a microcolorimetric assay with Alamar blue dye. None of the aqueous extracts had antimycobacterial activity. Hexane extracts from Artemisia ludoviciana, Chamaedora tepejilote, Lantana hispida, Juniperus communis and Malva parviflora, and methanol extracts from Artemisia ludoviciana and Juniperus communis inhibited the growth of Mycobacterium tuberculosis. Mycobacterium avium was inhibited by Juniperus communis hexane extract and by Malva parviflora methanol extract. The active extracts were tested against monoresistant variants of Mycobacterium tuberculosis H37Rv (isoniazid, rifampin, streptomycin and ethambutol resistant) and the hexane extract of Lantana hispida showed the best activity. Lantana hispida hexane extract was also active against a group of MDR-TB clinical isolates. In contrast, it did not inhibit the growth of non-tuberculous mycobacteria. The hexane extract of Lantana hispida was fractionated by column chromatography and one of its fractions (FVI) inhibited the growth of all the MDR-TB clinical isolates at concentrations up to 25 microg/mL. This study supports the fact that selecting plants by ethnobotanical criteria enhances the probability of finding species with activity against mycobacteria, and our results point to Lantana hispida as an important source of potential compounds against MDR-TB.

  19. Factors causing delay of access to tuberculosis diagnosis among new, active tuberculosis patients: a prospective cohort study.

    PubMed

    Shu, Wen; Chen, Wei; Zhu, Shiyu; Hou, Yongchun; Mei, Jian; Bai, Liqiong; Xu, Weiguo; Zhou, Lin; Nie, Shaofa; Cheng, Shiming; Xu, Yihua

    2014-01-01

    Few studies have examined, in a prospective cohort study, factors causing delay of access to tuberculosis (TB) diagnosis among new, active TB patients. A prospective cohort study (2009-2011) was carried out among 408 889 Chinese. Data on known/potential influencing factors were obtained from baseline questionnaires. We used stepwise logistic regression models to analyze the association between several known/potential influencing factors and diagnosis delay, assessed the current situation, and explored determinants of diagnosis delay. During follow-up and final visits, 202 new, active TB patients were found. Median patient delay was 5.4 (quartile 2.7-26) weeks, health system delay was 0 (quartile 0-1.6) weeks, and diagnosis delay was 9.9 (quartile 3.1-28.1) weeks. The influencing factors on patient delay were age and duration of symptoms. Smoking and sputum smear status were influencing factors for health system delay, and duration of symptoms was one of the factors for diagnosis delay. These findings provide information on the current situation of diagnosis delay and evidence for specific strategy development for TB control in China.

  20. A Method for Extracting Suspected Parotid Lesions in CT Images using Feature-based Segmentation and Active Contours based on Stationary Wavelet Transform

    NASA Astrophysics Data System (ADS)

    Wu, T. Y.; Lin, S. F.

    2013-10-01

    Automatic suspected lesion extraction is an important application in computer-aided diagnosis (CAD). In this paper, we propose a method to automatically extract the suspected parotid regions for clinical evaluation in head and neck CT images. The suspected lesion tissues in low contrast tissue regions can be localized with feature-based segmentation (FBS) based on local texture features, and can be delineated with accuracy by modified active contour models (ACM). At first, stationary wavelet transform (SWT) is introduced. The derived wavelet coefficients are applied to derive the local features for FBS, and to generate enhanced energy maps for ACM computation. Geometric shape features (GSFs) are proposed to analyze each soft tissue region segmented by FBS; the regions with higher similarity GSFs with the lesions are extracted and the information is also applied as the initial conditions for fine delineation computation. Consequently, the suspected lesions can be automatically localized and accurately delineated for aiding clinical diagnosis. The performance of the proposed method is evaluated by comparing with the results outlined by clinical experts. The experiments on 20 pathological CT data sets show that the true-positive (TP) rate on recognizing parotid lesions is about 94%, and the dimension accuracy of delineation results can also approach over 93%.

  1. Contribution of efflux activity to isoniazid resistance in the Mycobacterium tuberculosis complex.

    PubMed

    Rodrigues, Liliana; Machado, Diana; Couto, Isabel; Amaral, Leonard; Viveiros, Miguel

    2012-06-01

    Resistance to isoniazid (INH), one of the main drugs used in tuberculosis (TB) therapy, is mostly due to chromosomal mutations in target genes. However, approximately 20-30% of INH resistant Mycobacterium tuberculosis isolates do not have mutations in any of the genes associated with INH resistance. This suggests that other mechanism(s) may be involved, namely efflux pump systems capable of extruding the drug to the exterior of the cell. In a previous work, we have induced clinical INH susceptible M. tuberculosis isolates and the H37Rv reference strain to high-level resistance to INH, by gradual exposure to increasing concentrations of this drug. In the present study, we have characterized these strains and Mycobacterium bovis BCG induced to INH resistance with respect to their efflux activity and its contribution to INH resistance using the following approach: determination of the susceptibility to INH in the presence and absence of the efflux inhibitors (EIs) chlorpromazine, thioridazine and verapamil; evaluation of efflux activity by a semi-automated fluorometric method; and quantification of the expression level of genes coding for efflux pumps by real-time RT-qPCR. The EIs decreased INH resistance in the INH induced strains, in particular verapamil promoted a reversal of resistance in some of the strains tested. The induced strains presented an increased efflux activity that was inhibited by the EIs and showed overexpression of the efflux pump genes efpA, mmpL7, mmr, p55 and the Tap-like gene Rv1258c. Altogether, these results correlate efflux activity with INH resistance and demonstrate that efflux pumps play an important role in acquired INH resistance in M. tuberculosis complex. The development of EIs that can restore the antimicrobial activity of the antibiotic subject to efflux is an approach that can be useful in order to prevent the emergence of this resistance and guide the development of new effective anti-TB therapeutical approaches.

  2. Encapsulation of Anti-Tuberculosis Drugs within Mesoporous Silica and Intracellular Antibacterial Activities

    PubMed Central

    Xia, Xin; Pethe, Kevin; Kim, Ryangyeo; Ballell, Lluis; Barros, David; Cechetto, Jonathan; Jeon, HeeKyoung; Kim, Kideok; Garcia-Bennett, Alfonso E.

    2014-01-01

    Tuberculosis is a major problem in public health. While new effective treatments to combat the disease are currently under development, they tend suffer from poor solubility often resulting in low and/or inconsistent oral bioavailability. Mesoporous materials are here investigated in an in vitro intracellular assay, for the effective delivery of compound PA-824; a poorly soluble bactericidal agent being developed against Tuberculosis (TB). Mesoporous materials enhance the solubility of PA-824; however, this is not translated into a higher antibacterial activity in TB-infected macrophages after 5 days of incubation, where similar values are obtained. The lack of improved activity may be due to insufficient release of the drug from the mesopores in the context of the cellular environment. However, these results show promising data for the use of mesoporous particles in the context of oral delivery with expected improvements in bioavailability.

  3. Deregulated microRNAs in CD4+ T cells from individuals with latent tuberculosis versus active tuberculosis.

    PubMed

    Fu, Yurong; Yi, Zhengjun; Li, Jianhua; Li, Ruifang

    2014-03-01

    The mechanisms of latent tuberculosis (TB) infection remain elusive. Roles of microRNA (miRNA) have been highlighted in pathogen-host interactions recently. To identify miRNAs involved in the immune response to TB, expression profiles of miRNAs in CD4(+) T cells from patients with latent TB, active TB and healthy controls were investigated by microarray assay and validated by RT-qPCR. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were used to analyse the significant functions and involvement in signalling pathways of the differentially expressed miRNAs. To identify potential target genes for miR-29, interferon-γ (IFN-γ) mRNA expression was measured by RT-qPCR. Our results showed that 27 miRNAs were deregulated among the three groups. RT-qPCR results were generally consistent with the microarray data. We observed an inverse correlation between miR-29 level and IFN-γ mRNA expression in CD4(+) T cells. GO and KEGG pathway analysis showed that the possible target genes of deregulated miRNAs were significantly enriched in mitogen-activated protein kinase signalling pathway, focal adhesion and extracellular matrix receptor interaction, which might be involved in the transition from latent to active TB. In all, for the first time, our study revealed that some miRNAs in CD4(+) T cells were altered in latent and active TB. Function and pathway analysis highlighted the possible involvement of miRNA-deregulated mRNAs in TB. The study might help to improve understanding of the relationship between miRNAs in CD4(+) T cells and TB, and laid an important foundation for further identification of the underlying mechanisms of latent TB infection and its reactivation.

  4. Control measures to trace ≤ 15-year-old contacts of index cases of active pulmonary tuberculosis

    PubMed Central

    Oliveira, Cláudia Di Lorenzo; de Melo, Angelita Cristine; de Oliveira, Lílian Ruth Silva; Froede, Emerson Lopes; Camargos, Paulo

    2015-01-01

    This was descriptive study carried out in a medium-sized Brazilian city. In ≤ 15-year-old contacts of index cases of active pulmonary tuberculosis, we assessed compliance with the Brazilian national guidelines for tuberculosis control. We interviewed 43 contacts and their legal guardians. Approximately 80% of the contacts were not assessed by the municipal public health care system, and only 21% underwent tuberculin skin testing. The results obtained with the Chi-square Automatic Interaction Detector method suggest that health care teams have a biased attitude toward assessing such contacts and underscore the need for training health professionals regarding tuberculosis control programs. PMID:26578137

  5. BTLA exhibits immune memory for αβ T cells in patients with active pulmonary tuberculosis

    PubMed Central

    Zeng, Jin-Cheng; Lin, Dong-Zi; Yi, Lai-Long; Liu, Gan-Bin; Zhang, Hui; Wang, Wan-Dang; Zhang, Jun-Ai; Wu, Xian-Jing; Xiang, Wen-Yu; Kong, Bin; Chen, Zheng W; Wang, Cong-Yi; Xu, Jun-Fa

    2014-01-01

    Despite past extensive studies, the role of B and T lymphocyte attenuator (BTLA) in αβ T cells in patients with active pulmonary tuberculosis (ATB) remains poorly understood. Here we demonstrate that BTLA expression on αβ T cells is decreased in patients with M. tuberculosis (Mtb) infection. Particularly, BTLA expression levels are likely critical for αβ T cells to manifest and maintain an active central memory phenotype with high capacity for secretion of IFN-γ and perforin, which are important for immune memory against TB infection. BTLAhigh αβ T cells also exhibited higher capacity in response to Mtb peptide stimulation. In contrast to the role of BTLA played for negative regulation of immune responses, our data in the current studies suggest that BTLA expression on αβ T cells is likely associated with protective immune memory against Mtb infection in the setting of patients with active pulmonary tuberculosis. This previous unappreciated role for BTLA may have implications for prevention and treatment of patients with Mtb infection. PMID:25360214

  6. In vitro and in vivo activities of the nitroimidazole CGI 17341 against Mycobacterium tuberculosis.

    PubMed Central

    Ashtekar, D R; Costa-Perira, R; Nagrajan, K; Vishvanathan, N; Bhatt, A D; Rittel, W

    1993-01-01

    CGI 17341 (2-ethyl-5-nitro-2,3-dihydro[2-1b]imidazo-oxazole) is a novel orally active representative of the 5-nitroimidazole series of antimicrobial agents. At concentrations ranging from 0.1 to 0.3 micrograms/ml, CGI 17341 inhibited the drug-susceptible and multi-drug-resistant strains of Mycobacterium tuberculosis. CGI 17341 had no cross-resistance with isoniazid, rifampin, streptomycin, or ethambutol. While the in vitro activity of CGI 17341 against M. tuberculosis was comparable to those of isoniazid and rifampin, it was superior to those of streptomycin, ciprofloxacin or norfloxacin, and oxazolidinone DuP 721. The MIC of CGI 17341 was not affected when the pH of the medium was decreased from 6.8 to 5.6, while four- to sixfold increases in the MICs of ciprofloxacin and isoniazid were observed. In mice infected with M. tuberculosis, the 50% effective dose for CGI 17341 was 7.7 mg/kg of body weight (95% confidence limits, 3.5 and 10.27) when administered on days 11 and 12 postinfection. CGI 17341 gave a dose-dependent (r = 0.995) and significant increase in the survival time. Our data indicate that the 5-nitroimidazole CGI 17341 is a promising and novel antituberculosis compound with potent in vitro and in vivo activities. Further investigations on this compound are warranted. PMID:8452346

  7. The Activity of a Hexameric M17 Metallo-Aminopeptidase Is Associated With Survival of Mycobacterium tuberculosis

    PubMed Central

    Correa, Andre F.; Bastos, Izabela M. D.; Neves, David; Kipnis, Andre; Junqueira-Kipnis, Ana P.; de Santana, Jaime M.

    2017-01-01

    Mycobacterium tuberculosis is one of the most prevalent human pathogens causing millions of deaths in the last years. Moreover, tuberculosis (TB) treatment has become increasingly challenging owing to the emergence of multidrug resistant M. tuberculosis strains. Thus, there is an immediate need for the development of new anti-TB drugs. Proteases appear to be a promising approach and may lead to shortened and effective treatments for drug-resistant TB. Although the M. tuberculosis genome predicts more than 100 genes encoding proteases, only a few of them have been studied. Aminopeptidases constitute a set of proteases that selectively remove amino acids from the N-terminus of proteins and peptides and may act as virulence factors, essential for survival and maintenance of many microbial pathogens. Here, we characterized a leucine aminopeptidase of M. tuberculosis (MtLAP) as a cytosolic oligomeric metallo-aminopeptidase. Molecular and enzymatic properties lead us to classify MtLAP as a typical member of the peptidase family M17. Furthermore, the aminopeptidase inhibitor bestatin strongly inhibited MtLAP activity, in vitro M. tuberculosis growth and macrophage infection. In murine model of TB, bestatin treatment reduced bacterial burden and lesion in the lungs of infected mice. Thus, our data suggest that MtLAP participates in important metabolic pathways of M. tuberculosis necessary for its survival and virulence and consequently may be a promising target for new anti-TB drugs.

  8. Experience of active tuberculosis case finding in nearly 5 million households in India.

    PubMed

    Prasad, B M; Satyanarayana, S; Chadha, S S; Das, A; Thapa, B; Mohanty, S; Pandurangan, S; Babu, E R; Tonsing, J; Sachdeva, K S

    2016-03-21

    In India, to increase tuberculosis (TB) case detection under the National Tuberculosis Programme, active case finding (ACF) was implemented by the Global Fund-supported Project Axshya, among high-risk groups in 300 districts. Between April 2013 and December 2014, 4.9 million households covering ~20 million people were visited. Of 350 047 presumptive pulmonary TB cases (cough of ⩾2 weeks) identified, 187 586 (54%) underwent sputum smear examination and 14 447 (8%) were found to be smear-positive. ACF resulted in the detection of a large number of persons with presumptive pulmonary TB and smear-positive TB. Ensuring sputum examination of all those with presumptive TB was a major challenge.

  9. Measurement of Phenotype and Absolute Number of Circulating Heparin-Binding Hemagglutinin, ESAT-6 and CFP-10, and Purified Protein Derivative Antigen-Specific CD4 T Cells Can Discriminate Active from Latent Tuberculosis Infection

    PubMed Central

    Barkham, Timothy M. S.; Tang, Wenying; Kemeny, David M.; Chee, Cynthia Bin-Eng; Wang, Yee T.

    2014-01-01

    The tuberculin skin test (TST) and interferon gamma (IFN-γ) release assays (IGRAs) are used as adjunctive tests for the evaluation of suspected cases of active tuberculosis (TB). However, a positive test does not differentiate latent from active TB. We investigated whether flow cytometric measurement of novel combinations of intracellular cytokines and surface makers on CD4 T cells could differentiate between active and latent TB after stimulation with Mycobacterium tuberculosis-specific proteins. Blood samples from 60 patients referred to the Singapore Tuberculosis Control Unit for evaluation for active TB or as TB contacts were stimulated with purified protein derivative (PPD), ESAT-6 and CFP-10, or heparin-binding hemagglutinin (HBHA). The CD4 T cell cytokine response (IFN-γ, interleukin-2 [IL-2], interleukin-17A [IL-17A], interleukin-22 [IL-22], granulocyte-macrophage colony-stimulating factor [GM-CSF], and tumor necrosis factor alpha [TNF-α]) and surface marker expression (CD27, CXCR3, and CD154) were then measured. We found that the proportion of PPD-specific CD4 T cells, defined as CD154+ TNF-α+ cells that were negative for CD27 and positive for GM-CSF, gave the strongest discrimination between subjects with latent and those with active TB (area under the receiver operator characteristic [ROC] curve of 0.9277; P < 0.0001). Also, the proportions and absolute numbers of HBHA-specific CD4 T cells were significantly higher in those with latent TB infection, particularly CD154+ TNF-α+ IFN-γ+ IL-2+ and CD154+ TNF-α+ CXCR3+. Finally, we found that the ratio of ESAT-6- and CFP-10-responding to HBHA-responding CD4 T cells was significantly different between the two study populations. In conclusion, we found novel markers of M. tuberculosis-specific CD4 cells which differentiate between active and latent TB. PMID:25520147

  10. Mycobacterium tuberculosis Rv1096 protein: gene cloning, protein expression, and peptidoglycan deacetylase activity

    PubMed Central

    2014-01-01

    Background Many bacteria modulate and evade the immune defenses of their hosts through peptidoglycan (PG) deacetylation. The PG deacetylases from Streptococcus pneumonia, Listeria monocytogenes and Lactococcus lactis have been characterized. However, thus far, the PG deacetylase of Mycobacterium tuberculosis has not been identified. Results In this study, we cloned the Rv1096 gene from the M. tuberculosis H37Rv strain and expressed Rv1096 protein in both Escherichia coli and M. smegmatis. The results showed that the purified Rv1096 protein possessed metallo-dependent PG deacetylase activity, which increased in the presence of Co2+. The kinetic parameters of the PG deacetylase towards M. smegmatis PG as a substrate were as follows: Km, 0.910 ± 0.007 mM; Vmax, 0.514 ± 0.038 μMmin-1; and Kcat = 0.099 ± 0.007 (S-1). Additionally, the viability of M. smegmatis in the presence of over-expressed Rv1096 protein was 109-fold higher than that of wild-type M. smegmatis after lysozyme treatment. Additionally, light microscopy and scanning electron microscopy showed that in the presence of over-expressed Rv1096 protein, M. smegmatis kept its regular shape, with an undamaged cell wall and smooth surface. These results indicate that Rv1096 caused deacetylation of cell wall PG, leading to lysozyme resistance in M. smegmatis. Conclusion We have determined that M. tuberculosis Rv1096 is a PG deacetylase. The PG deacetylase activity of Rv1096 contributed to lysozyme resistance in M. smegmatis. Our findings suggest that deacetylation of cell wall PG may be involved in evasion of host immune defenses by M. tuberculosis. PMID:24975018

  11. Reduced frequency of memory T cells and increased Th17 responses in patients with active tuberculosis.

    PubMed

    Marín, Nancy D; París, Sara C; Rojas, Mauricio; García, Luis F

    2012-10-01

    Phenotypic and functional alterations in Mycobacterium tuberculosis T cell subsets have been reported in patients with active tuberculosis. A better understanding of these alterations will increase the knowledge about immunopathogenesis and also may contribute to the development of new diagnostics and prophylactic strategies. Here, the ex vivo phenotype of CD4(+) and CD8(+) T cells and the frequency and phenotype of gamma interferon (IFN-γ)- and interleukin 17 (IL-17)-producing cells elicited in short-term and long-term cultures following CFP-10 and purified protein derivative (PPD) stimulation were determined in noninfected persons (non-TBi), latently infected persons (LTBi), and patients with active tuberculosis (ATB). Phenotypic characterization of T cells was done based on the expression of CD45RO and CD27. Results show that ATB had a reduced frequency of circulating CD4(+) CD45RO(+) CD27(+) T cells and an increased frequency of CD4(+) CD45RO(-) CD27(+) T cells. ATB also had a higher frequency of circulating IL-17-producing CD4(+) T cells than did LTBi after PPD stimulation, whereas LTBi had more IFN-γ-producing CD4(+) T cells than did non-TBi. The phenotype of IFN-γ-producing cells at 24 h differs from the phenotype of IL-17-producing cells with no differences between LTBi and ATB. At 144 h, IFN-γ- and IL-17-producing cells were mainly CD45RO(+) CD27(+) T cells and they were more frequent in ATB. These results suggest that M. tuberculosis infection induces alterations in T cells which interfere with an adequate specific immune response.

  12. Reduced Frequency of Memory T Cells and Increased Th17 Responses in Patients with Active Tuberculosis

    PubMed Central

    Marín, Nancy D.; París, Sara C.; Rojas, Mauricio

    2012-01-01

    Phenotypic and functional alterations in Mycobacterium tuberculosis T cell subsets have been reported in patients with active tuberculosis. A better understanding of these alterations will increase the knowledge about immunopathogenesis and also may contribute to the development of new diagnostics and prophylactic strategies. Here, the ex vivo phenotype of CD4+ and CD8+ T cells and the frequency and phenotype of gamma interferon (IFN-γ)- and interleukin 17 (IL-17)-producing cells elicited in short-term and long-term cultures following CFP-10 and purified protein derivative (PPD) stimulation were determined in noninfected persons (non-TBi), latently infected persons (LTBi), and patients with active tuberculosis (ATB). Phenotypic characterization of T cells was done based on the expression of CD45RO and CD27. Results show that ATB had a reduced frequency of circulating CD4+ CD45RO+ CD27+ T cells and an increased frequency of CD4+ CD45RO− CD27+ T cells. ATB also had a higher frequency of circulating IL-17-producing CD4+ T cells than did LTBi after PPD stimulation, whereas LTBi had more IFN-γ-producing CD4+ T cells than did non-TBi. The phenotype of IFN-γ-producing cells at 24 h differs from the phenotype of IL-17-producing cells with no differences between LTBi and ATB. At 144 h, IFN-γ- and IL-17-producing cells were mainly CD45RO+ CD27+ T cells and they were more frequent in ATB. These results suggest that M. tuberculosis infection induces alterations in T cells which interfere with an adequate specific immune response. PMID:22914361

  13. Role of Metal Ions on the Activity of Mycobacterium tuberculosis Pyrazinamidase

    PubMed Central

    Sheen, Patricia; Ferrer, Patricia; Gilman, Robert H.; Christiansen, Gina; Moreno-Román, Paola; Gutiérrez, Andrés H.; Sotelo, Jun; Evangelista, Wilfredo; Fuentes, Patricia; Rueda, Daniel; Flores, Myra; Olivera, Paula; Solis, José; Pesaresi, Alessandro; Lamba, Doriano; Zimic, Mirko

    2012-01-01

    Pyrazinamidase of Mycobacterium tuberculosis catalyzes the conversion of pyrazinamide to the active molecule pyrazinoic acid. Reduction of pyrazinamidase activity results in a level of pyrazinamide resistance. Previous studies have suggested that pyrazinamidase has a metal-binding site and that a divalent metal cofactor is required for activity. To determine the effect of divalent metals on the pyrazinamidase, the recombinant wild-type pyrazinamidase corresponding to the H37Rv pyrazinamide-susceptible reference strain was expressed in Escherichia coli with and without a carboxy terminal. His-tagged pyrazinamidase was inactivated by metal depletion and reactivated by titration with divalent metals. Although Co2+, Mn2+, and Zn2+ restored pyrazinamidase activity, only Co2+ enhanced the enzymatic activity to levels higher than the wild-type pyrazinamidase. Cu2+, Fe2+, Fe3+, and Mg2+ did not restore the activity under the conditions tested. Various recombinant mutated pyrazinamidases with appropriate folding but different enzymatic activities showed a differential pattern of recovered activity. X-ray fluorescence and atomic absorbance spectroscopy showed that recombinant wild-type pyrazinamidase expressed in E. coli most likely contained Zn. In conclusion, this study suggests that M. tuberculosis pyrazinamidase is a metalloenzyme that is able to coordinate several ions, but in vivo, it is more likely to coordinate Zn2+. However, in vitro, the metal-depleted enzyme could be reactivated by several divalent metals with higher efficiency than Zn. PMID:22764307

  14. Detection and confirmation of alkaloids in leaves of Justicia adhatoda and bioinformatics approach to elicit its anti-tuberculosis activity.

    PubMed

    Jha, Deepak Kumar; Panda, Likun; Lavanya, P; Ramaiah, Sudha; Anbarasu, Anand

    2012-11-01

    The extraction and determination of alkaloids was performed and confirmed by phytochemical analysis. Six different quinazoline alkaloids (vasicoline, vasicolinone, vasicinone, vasicine, adhatodine and anisotine) were found in the leaf of Justicia adhatoda (J. adhatoda). The presence of the peaks obtained through HPLC indicated the diverse nature of alkaloid present in the leaf. The enzyme β-ketoacyl-acyl-carrier protein synthase III that catalyses the initial step of fatty acid biosynthesis (FabH) via a type II fatty acid synthase has unique structural features and universal occurrence in Mycobacterium tuberculosis (M. tuberculosis). Thus, it was considered as a target for designing of anti-tuberculosis compounds. Docking simulations were conducted on the above alkaloids derived from J. adhatoda. The combination of docking/scoring provided interesting insights into the binding of different inhibitors and their activity. These results will be useful for designing inhibitors for M. tuberculosis and also will be a good starting point for natural plant-based pharmaceutical chemistry.

  15. The characteristic profiles of PD-1 and PD-L1 expressions and dynamic changes during treatment in active tuberculosis.

    PubMed

    Shen, Lei; Shi, Hong; Gao, Yan; Ou, Qinfang; Liu, Qianqian; Liu, Yuanyuan; Wu, Jing; Zhang, Wenhong; Fan, Lin; Shao, Lingyun

    2016-12-01

    PD-1 is a cell surface receptor of activated T and B lymphocytes and it's role in tuberculosis is controversial because of lack of congruence between clinical study and animal model. To investigate the immunological pathogenesis mechanisms of tuberculosis and to develop the immune therapy target essential for controlling tuberculosis, here we explored the expression characteristics and dynamic changes of PD-1/PD-L1 pathway in different CD4+T cell subsets. We enrolled 24 human subjects including 15 active tuberculosis (ATB) patients and 9 healthy donors (HD). The expressions of PD-1 and PD-L1 on CD4+T cells increased significantly in ATB patients than HD. ATB patients had a higher proportion of regulatory T cells (Treg, CD4(+)CD25 + Foxp3+) than HD. The expressions of PD-1 and PD-L1 increased remarkably on CD4+T cell subsets, including Treg cells, Tresp (CD4(+)CD25(-)) cells and Teff (CD4(+)CD25 + Foxp3-) cells. Finally, clinical improvement following effective anti-TB therapy is correlated with significantly decreased expression of PD-1 in Tresp and Teff cells, but not in Treg cells. Thus, expression profiles of PD-1 in T cell subpopulations may be used as a candidate to predict the clinical efficacy of anti-tuberculosis therapy. Modulation of PD-1/PD-L1 pathway in CD4 subsets may offer an immunotherapy target for the control of tuberculosis.

  16. Efflux pumps of Mycobacterium tuberculosis play a significant role in antituberculosis activity of potential drug candidates.

    PubMed

    Balganesh, Meenakshi; Dinesh, Neela; Sharma, Sreevalli; Kuruppath, Sanjana; Nair, Anju V; Sharma, Umender

    2012-05-01

    Active efflux of drugs mediated by efflux pumps that confer drug resistance is one of the mechanisms developed by bacteria to counter the adverse effects of antibiotics and chemicals. To understand these efflux mechanisms in Mycobacterium tuberculosis, we generated knockout (KO) mutants of four efflux pumps of the pathogen belonging to different classes. We measured the MICs and kill values of two different compound classes on the wild type (WT) and the efflux pump (EP) KO mutants in the presence and absence of the efflux inhibitors verapamil and l-phenylalanyl-l-arginyl-β-naphthylamide (PAβN). Among the pumps studied, the efflux pumps belonging to the ABC (ATP-binding cassette) class, encoded by Rv1218c, and the SMR (small multidrug resistance) class, encoded by Rv3065, appear to play important roles in mediating the efflux of different chemical classes and antibiotics. Efflux pumps encoded by Rv0849 and Rv1258c also mediate the efflux of these compounds, but to a lesser extent. Increased killing is observed in WT M. tuberculosis cells by these compounds in the presence of either verapamil or PAβN. The efflux pump KO mutants were more susceptible to these compounds in the presence of efflux inhibitors. We have shown that these four efflux pumps of M. tuberculosis play a vital role in mediating efflux of different chemical scaffolds. Inhibitors of one or several of these efflux pumps could have a significant impact in the treatment of tuberculosis. The identification and characterization of Rv0849, a new efflux pump belonging to the MFS (major facilitator superfamily) class, are reported.

  17. Systematic Survey of Serine Hydrolase Activity in Mycobacterium tuberculosis Defines Changes Associated with Persistence

    SciTech Connect

    Ortega, Corrie; Anderson, Lindsey N.; Frando, Andrew; Sadler, Natalie C.; Brown, Robert W.; Smith, Richard D.; Wright, Aaron T.; Grundner, Christoph

    2016-02-01

    The transition between replication and non-replication underlies much of Mycobacterium tuberculosis (Mtb) pathogenicity, as non- or slowly replicating Mtb are responsible for persistence and poor treatment outcomes. Therapeutic targeting of non-replicating, persistent populations is a priority for tuberculosis treatment, but only few drug targets in non-replicating Mtb are currently known. Here, we directly measure the activity of the highly diverse and druggable serine hydrolases (SHs) during active replication and non-replication by activity-based proteomics. We predict serine hydrolase activity for 78 proteins, including 27 proteins with previously unknown function, and identify 37 SHs that remain active even in the absence of replication, providing a set of candidate persistence targets. Non-replication was associated with large shifts in the activity of the majority of SHs. These activity changes were largely independent of SH abundance, indicating extensive post-translational regulation. By probing a large cross-section of druggable Mtb enzyme space during replication and non-replication, we identify new SHs and suggest new persistence targets.

  18. Tuberculosis Infection and Latent Tuberculosis

    PubMed Central

    2016-01-01

    Active tuberculosis (TB) has a greater burden of TB bacilli than latent TB and acts as an infection source for contacts. Latent tuberculosis infection (LTBI) is the state in which humans are infected with Mycobacterium tuberculosis without any clinical symptoms, radiological abnormality, or microbiological evidence. TB is transmissible by respiratory droplet nucleus of 1–5 µm in diameter, containing 1–10 TB bacilli. TB transmission is affected by the strength of the infectious source, infectiousness of TB bacilli, immunoresistance of the host, environmental stresses, and biosocial factors. Infection controls to reduce TB transmission consist of managerial activities, administrative control, engineering control, environmental control, and personal protective equipment provision. However, diagnosis and treatment for LTBI as a national TB control program is an important strategy on the precondition that active TB is not missed. Therefore, more concrete evidences for LTBI management based on clinical and public perspectives are needed. PMID:27790271

  19. Tuberculosis (TB)

    MedlinePlus

    ... with facebook share with twitter share with linkedin Tuberculosis (TB) Tuberculosis (TB) is a contagious and often ... are drug resistant. Why Is the Study of Tuberculosis (TB) a Priority for NIAID? Tuberculosis is one ...

  20. Biomarkers for risk of developing active tuberculosis in contacts of TB patients: a prospective cohort study.

    PubMed

    Rakotosamimanana, Niaina; Richard, Vincent; Raharimanga, Vaomalala; Gicquel, Brigitte; Doherty, T Mark; Zumla, Alimuddin; Rasolofo Razanamparany, Voahangy

    2015-10-01

    Identifying those Mycobacterium tuberculosis latent-infected individuals most at risk of developing active tuberculosis (TB) using routine clinical and laboratory tests remains a huge challenge in TB control efforts. We conducted a prospective longitudinal study of clinical and laboratory markers associated with the risk of developing active TB in contacts with latent M. tuberculosis infection.HIV-negative household contacts (n=296) of pulmonary TB patients underwent monitoring of clinical features, full blood cell counts, tuberculin skin text (TST) and chest radiography performed regularly during 18 months of follow-up. Paired statistical tests, a Kaplan-Meier analysis and Cox proportional hazard modelling were performed on variables between contacts progressing or not progressing to active TB.The appearance of TB disease symptoms in contacts was significantly associated with an elevated peripheral percentage of blood monocytes (adjusted hazard ratio (aHR) 6.25, 95% CI 1.63-23.95; p<0.01), a ≥14 mm TST response (aHR 5.72, 95% CI 1.22-26.80; p=0.03) and an increased monocyte:lymphocyte ratio (aHR 4.97, 95% CI 1.3-18.99; p=0.03). Among contacts having TST ≥14 mm, a strong association with risk of progression to TB was found with an elevated blood monocyte percentage (aHR 8.46, 95% CI 1.74-41.22; p<0.01).Elevated percentage of peripheral blood monocytes plus an elevated TST response are potential biomarkers for identifying contacts of TB patients at highest risk of developing active TB.

  1. Mefloquine and its oxazolidine derivative compound are active against drug-resistant Mycobacterium tuberculosis strains and in a murine model of tuberculosis infection.

    PubMed

    Rodrigues-Junior, Valnês S; Villela, Anne D; Gonçalves, Raoni S B; Abbadi, Bruno Lopes; Trindade, Rogério Valim; López-Gavín, Alexandre; Tudó, Griselda; González-Martín, Julian; Basso, Luiz Augusto; de Souza, Marcus V N; Campos, Maria Martha; Santos, Diógenes Santiago

    2016-08-01

    Repurposing of drugs to treat tuberculosis (TB) has been considered an alternative to overcome the global TB epidemic, especially to combat drug-resistant forms of the disease. Mefloquine has been reported as a potent drug to kill drug-resistant strains of Mycobacterium tuberculosis. In addition, mefloquine-derived molecules have been synthesised and their effectiveness against mycobacteria has been assessed. In this work, we demonstrate for the first time the activities of mefloquine and its oxazolidine derivative compound 1E in a murine model of TB infection following administration of both drugs by the oral route. The effects of associations between mefloquine or 1E with the clinically used antituberculosis drugs isoniazid, rifampicin, ethambutol, moxifloxacin and streptomycin were also investigated. Importantly, combination of mefloquine with isoniazid and of 1E with streptomycin showed a two-fold decrease in their minimum inhibitory concentrations (MICs). Moreover, no tested combinations demonstrated antagonist interactions. Here we describe novel evidence on the activity of mefloquine and 1E against a series of quinolone-resistant M. tuberculosis strains. These data show MICs against quinolone-resistant strains (0.5-8 µg/mL) similar to or lower than those previously reported for multidrug-resistant strains. Taking these results together, we can suggest the use of mefloquine or 1E in combination with clinically available drugs, especially in the case of resistant forms of TB.

  2. Mycobacterium tuberculosis Rv2882c Protein Induces Activation of Macrophages through TLR4 and Exhibits Vaccine Potential

    PubMed Central

    Back, Yong Woo; Park, Hye-Soo; Bae, Hyun Shik; Choi, Chul Hee; Kim, Hwa-Jung

    2016-01-01

    Macrophages constitute the first line of defense against Mycobacterium tuberculosis and are critical in linking innate and adaptive immunity. Therefore, the identification and characterization of mycobacterial proteins that modulate macrophage function are essential for understanding tuberculosis pathogenesis. In this study, we identified the novel macrophage-activating protein, Rv2882c, from M. tuberculosis culture filtrate proteins. Recombinant Rv2882c protein activated macrophages to secrete pro-inflammatory cytokines and express co-stimulatory and major histocompatibility complex molecules via Toll-like receptor 4, myeloid differentiation primary response protein 88, and Toll/IL-1 receptor-domain-containing adaptor inducing IFN-beta. Mitogen-activated protein kinases and NF-κB signaling pathways were involved in Rv2882c-induced macrophage activation. Further, Rv2882c-treated macrophages induced expansion of the effector/memory T cell population and Th1 immune responses. In addition, boosting Bacillus Calmette-Guerin vaccination with Rv2882c improved protective efficacy against M. tuberculosis in our model system. These results suggest that Rv2882c is an antigen that could be used for tuberculosis vaccine development. PMID:27711141

  3. Activity against Mycobacterium smegmatis and M. tuberculosis by extract of South African medicinal plants.

    PubMed

    Mativandlela, Sannah Patience Nkami; Meyer, Jacob Jacobus Marion; Hussein, Ahmed A; Houghton, Peter J; Hamilton, Chris J; Lall, Namrita

    2008-06-01

    Seven ethnobotanically selected medicinal plants were screened for their antimycobacterial activity. The minimum inhibitory concentration (MIC) of four plants namely Artemisia afra, Dodonea angustifolia, Drosera capensis and Galenia africana ranged from 0.781 to 6.25 mg/mL against Mycobacterium smegmatis. G. africana showed the best activity exhibiting an MIC of 0.78 mg/mL and a minimum bactericidal concentration (MBC) of 1.56 mg/mL. The MICs of ethanol extracts of D. angustifolia and G. africana against M. tuberculosis were found to be 5.0 and 1.2 mg/mL respectively. The mammalian cytotoxicity IC(50) value of the most active antimycobacterial extract, from G. africana, was found to be 101.3 microg/mL against monkey kidney Vero cells. Since the ethanol G. africana displayed the best antimycobacterial activity, it was subjected to fractionation which led to the isolation of a flavone, 5,7,2'-trihydroxyflavone. The MIC of this compound was found to be 0.031 mg/mL against M. smegmatis and 0.10 mg/mL against M. tuberculosis. This study gives some scientific basis to the traditional use of these plants for TB-related symptoms.

  4. Identification and structure-activity relationship study of carvacrol derivatives as Mycobacterium tuberculosis chorismate mutase inhibitors.

    PubMed

    Alokam, Reshma; Jeankumar, Variam Ullas; Sridevi, Jonnalagadda Padma; Matikonda, Siddharth Sai; Peddi, Santosh; Alvala, Mallika; Yogeeswari, Perumal; Sriram, Dharmarajan

    2014-08-01

    In the present study, we identified carvacrol, a major phenolic component of oregano oil as a novel small molecule inhibitor of Mycobacterium tuberculosis (MTB) chorismate mutase (CM) enzyme with IC50 of 1.06 ± 0.4 µM. Virtual screening of the BITS-Pilani in-house database using the crystal structure of the MTB CM bound transition state intermediate (PDB: 2FP2) as framework identified carvacrol as a potential lead. Further various carvacrol derivatives were evaluated in vitro for their ability to inhibit MTB CM enzyme, whole cell MTB and cytotoxicity as steps toward the derivation of structure-activity relationships (SAR) and lead optimization.

  5. A model to predict anti-tuberculosis activity: value proposition for marine microorganisms.

    PubMed

    Liu, Miaomiao; Grkovic, Tanja; Zhang, Lixin; Liu, Xueting; Quinn, Ronald J

    2016-08-01

    The development of new antibiotics effective against all strains of tuberculosis (TB) is needed. To evaluate the potential of marine microbe-derived natural products as anti-TB leads, we analyzed and compared the physico-chemical properties of 39 current TB drugs and candidates against 60 confirmed mycobacteria-active natural products. We showed that anti-TB natural products sourced from marine microbes have a large overlap with TB drug-like space. A model to predict potential anti-TB drugs is proposed.

  6. Synthesis and Anti-Tuberculosis Activity of the Marine Natural Product Caulerpin and Its Analogues

    PubMed Central

    Canché Chay, Cristina I.; Gómez Cansino, Rocío; Espitia Pinzón, Clara I.; Torres-Ochoa, Rubén O.; Martínez, Roberto

    2014-01-01

    Caulerpin (1a), a bis-indole alkaloid from the marine algal Caulerpa sp., was synthesized in three reaction steps with an overall yield of 11%. The caulerpin analogues (1b–1g) were prepared using the same synthetic pathway with overall yields between 3% and 8%. The key reaction involved a radical oxidative aromatic substitution involving xanthate (3) and 3-formylindole compounds (4a–4g). All bis-indole compounds synthesized were evaluated against the Mycobacterium tuberculosis strain H37Rv, and 1a was found to display excellent activity (IC50 0.24 µM). PMID:24681629

  7. Non-transpeptidase binding arylthioether β-lactams active against Mycobacterium tuberculosis and Moraxella catarrhalis.

    PubMed

    Beck, Tim N; Lloyd, Dina; Kuskovsky, Rostislav; Minah, Jeanette; Arora, Kriti; Plotkin, Balbina J; Green, Jacalyn M; Boshoff, Helena I; Barry, Clifton; Deschamps, Jeffrey; Konaklieva, Monika I

    2015-02-01

    The prevalence of drug resistance in both clinical and community settings as a consequence of alterations of biosynthetic pathways, enzymes or cell wall architecture is a persistent threat to human health. We have designed, synthesized, and tested a novel class of non-transpeptidase, β-lactamase resistant monocyclic β-lactams that carry an arylthio group at C4. These thioethers exhibit inhibitory and cidal activity against serine β-lactamase producing Mycobacterium tuberculosis wild type strain (Mtb) and multiple (n=8) β-lactamase producing Moraxella catarrhalis clinical isolates.

  8. The Cytosolic Sensor cGAS Detects Mycobacterium tuberculosis DNA to Induce Type I Interferons and Activate Autophagy.

    PubMed

    Watson, Robert O; Bell, Samantha L; MacDuff, Donna A; Kimmey, Jacqueline M; Diner, Elie J; Olivas, Joanna; Vance, Russell E; Stallings, Christina L; Virgin, Herbert W; Cox, Jeffery S

    2015-06-10

    Type I interferons (IFNs) are critical mediators of antiviral defense, but their elicitation by bacterial pathogens can be detrimental to hosts. Many intracellular bacterial pathogens, including Mycobacterium tuberculosis, induce type I IFNs following phagosomal membrane perturbations. Cytosolic M. tuberculosis DNA has been implicated as a trigger for IFN production, but the mechanisms remain obscure. We report that the cytosolic DNA sensor, cyclic GMP-AMP synthase (cGAS), is required for activating IFN production via the STING/TBK1/IRF3 pathway during M. tuberculosis and L. pneumophila infection of macrophages, whereas L. monocytogenes short-circuits this pathway by producing the STING agonist, c-di-AMP. Upon sensing cytosolic DNA, cGAS also activates cell-intrinsic antibacterial defenses, promoting autophagic targeting of M. tuberculosis. Importantly, we show that cGAS binds M. tuberculosis DNA during infection, providing direct evidence that this unique host-pathogen interaction occurs in vivo. These data uncover a mechanism by which IFN is likely elicited during active human infections.

  9. 38 CFR 3.370 - Pulmonary tuberculosis shown by X-ray in active service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Pulmonary tuberculosis... Rating Considerations Relative to Specific Diseases § 3.370 Pulmonary tuberculosis shown by X-ray in... connection for pulmonary tuberculosis. When under consideration, all available service department films...

  10. Mycobacterium tuberculosis heat shock proteins use diverse Toll-like receptor pathways to activate pro-inflammatory signals.

    PubMed

    Bulut, Yonca; Michelsen, Kathrin S; Hayrapetian, Linda; Naiki, Yoshikazu; Spallek, Ralf; Singh, Mahavir; Arditi, Moshe

    2005-06-03

    Although the Toll-like receptors used by Mycobacterium tuberculosis membrane and secreted factors are known, the pathways activated by M. tuberculosis heat shock proteins are not. An efficient immune response against the intracellular pathogen M. tuberculosis is critically dependent on rapid detection of the invading pathogen by the innate immune system and coordinated activation of the adaptive immune response. Macrophage phagocytosis of M. tuberculosis is accompanied by activation of the transcription factor NF-kappaB and secretion of inflammatory mediators that play an important role in granuloma formation and immune protection during M. tuberculosis infection. The interaction between M. tuberculosis and the various Toll-like receptors is complex, and it appears that distinct mycobacterial components may interact with different members of the Toll-like receptor family. Here we show that recombinant, purified, mycobacterial heat shock proteins 65 and 70 induce NF-kappaB activity in a dose-dependent manner in human endothelial cells. Furthermore, we show that whereas mycobacterial heat shock protein 65 signals exclusively through Toll-like receptor 4, heat shock protein 70 also signals through Toll-like receptor 2. Mycobacterial heat shock protein 65-induced NF-kappaB activation was MyD88-, TIRAP-, TRIF-, and TRAM-dependent and required the presence of MD-2. A better understanding of the recognition of mycobacterial heat shock proteins and their role in the host immune response to the pathogen may open the way to a better understanding of the immunological processes induced by this important human pathogen and the host-pathogen interactions and may help in the rational design of more effective vaccines or vaccine adjuvants.

  11. Whole genome analysis of Mycobacterium tuberculosis isolates from recurrent episodes of tuberculosis, Finland, 1995-2013.

    PubMed

    Korhonen, V; Smit, P W; Haanperä, M; Casali, N; Ruutu, P; Vasankari, T; Soini, H

    2016-06-01

    Recurrent tuberculosis (TB) is caused by an endogenous re-activation of the same strain of Mycobacterium tuberculosis (relapse) or exogenous infection with a new strain (re-infection). Recurrence of TB in Finland was analysed in a population-based, 19-year study, and genotyping was used to define relapse and re-infection. The M. tuberculosis isolates from patients with suspected relapse were further analysed by whole genome sequencing (WGS) to determine the number and type of mutations occurring in the bacterial genome between the first and second disease episodes. In addition, publicly available tools (PhyResSE and SpolPred) were used to predict drug resistance and spoligotype profile from the WGS data. Of the 8299 notified TB cases, 48 (0.6%) patients had episodes classified as recurrent. Forty-two patients had more than one culture-confirmed TB episode, and isolates from two episodes in 21 patients were available for genotyping. In 18 patients, the M. tuberculosis isolates obtained from the first and second TB episodes had identical spoligotypes. The WGS analysis of the 36 M. tuberculosis isolates from the 18 suspected relapse patients (average time between isolates 2.8 years) revealed 0 to 38 single nucleotide polymorphisms (median 1, mean 3.78) between the first and second isolate. There seemed to be no direct relation between the number of years between the two isolates, or treatment outcome, and the number of single nucleotide polymorphisms. The results suggest that the mutation rate may depend on multiple host-, strain- and treatment-related factors.

  12. Ion Channel Blockers as Antimicrobial Agents, Efflux Inhibitors, and Enhancers of Macrophage Killing Activity against Drug Resistant Mycobacterium tuberculosis

    PubMed Central

    Perdigão, João; Couto, Isabel; Portugal, Isabel; Martins, Marta; Amaral, Leonard; Anes, Elsa; Viveiros, Miguel

    2016-01-01

    Given the ability of M. tuberculosis to survive as an intracellular pathogen and its propensity to develop resistance to the existing antituberculosis drugs, its treatment requires new approaches. Here the antimycobacterial properties of verapamil, thioridazine, chlorpromazine, flupenthixol and haloperidol were investigated against a panel of drug resistant M. tuberculosis strains, both in vitro and on human-infected macrophages. These compounds are efflux inhibitors that share among them the characteristic of being ion channel blockers. In vitro, all compounds exhibited synergistic inhibitory activities when combined with isoniazid and rifampicin, and were able to inhibit active efflux, demonstrating their role as efflux inhibitors. Gene expression analysis showed that M. tuberculosis efflux genes were overexpressed in response to antibiotic exposure, in vitro and within macrophages, irrespective of their resistance pattern. These compounds displayed a rapid and high killing activity against M. tuberculosis, associated with a decrease in intracellular ATP levels demonstrating that the bactericidal action of the ion channel blockers against M. tuberculosis clinical strains is associated with their interference with energy metabolism. The compounds led to a decrease in the intracellular mycobacterial load by increasing phagosome acidification and activating lysosomal hydrolases. The results presented in this study enable us to propose the following mechanism of action for these compounds: a) in the bacteria, the compounds generate a cascade of events involving the inhibition of the respiratory chain complexes and energy production for efflux activity. Indirectly, this reduce the resistance level to antituberculosis drugs potentiating their activity; b) on the host cell, the treatment with the ion channel blockers increases phagosome acidification and induces the expression of phagosomal hydrolases, leading to bacterial growth restriction irrespective of their

  13. Characterization of activity and expression of isocitrate lyase in Mycobacterium avium and Mycobacterium tuberculosis.

    PubMed

    Höner Zu Bentrup, K; Miczak, A; Swenson, D L; Russell, D G

    1999-12-01

    Analysis by two-dimensional gel electrophoresis revealed that Mycobacterium avium expresses several proteins unique to an intracellular infection. One abundant protein with an apparent molecular mass of 50 kDa was isolated, and the N-terminal sequence was determined. It matches a sequence in the M. tuberculosis database (Sanger) with similarity to the enzyme isocitrate lyase of both Corynebacterium glutamicum and Rhodococcus fascians. Only marginal similarity was observed between this open reading frame (ORF) (termed icl) and a second distinct ORF (named aceA) which exhibits a low similarity to other isocitrate lyases. Both ORFs can be found as distinct genes in the various mycobacterial databases recently published. Isocitrate lyase is a key enzyme in the glyoxylate cycle and is essential as an anapleurotic enzyme for growth on acetate and certain fatty acids as carbon source. In this study we express and purify Icl, as well as AceA proteins, and show that both exhibit isocitrate lyase activity. Various known inhibitors for isocitrate lyase were effective. Furthermore, we present evidence that in both M. avium and M. tuberculosis the production and activity of the isocitrate lyase is enhanced under minimal growth conditions when supplemented with acetate or palmitate.

  14. High Affinity Inha Inhibitors with Activity Against Drug-Resistant Strains of Mycobacterium Tuberculosis

    SciTech Connect

    Sullivan,T.; Truglio, J.; Boyne, M.; Novichenok, P.; Zhang, X.; Stratton, C.; Li, H.; Kaur, T.; Amin, A.; et al.

    2006-01-01

    Novel chemotherapeutics for treating multidrug-resistant (MDR) strains of Mycobacterium tuberculosis (MTB) are required to combat the spread of tuberculosis, a disease that kills more than 2 million people annually. Using structure-based drug design, we have developed a series of alkyl diphenyl ethers that are uncompetitive inhibitors of InhA, the enoyl reductase enzyme in the MTB fatty acid biosynthesis pathway. The most potent compound has a Ki{prime} value of 1 nM for InhA and MIC{sub 99} values of 2-3 {micro}g mL{sup -1} (6-10 {micro}M) for both drug-sensitive and drug-resistant strains of MTB. Overexpression of InhA in MTB results in a 9-12-fold increase in MIC{sub 99}, consistent with the belief that these compounds target InhA within the cell. In addition, transcriptional response studies reveal that the alkyl diphenyl ethers fail to upregulate a putative efflux pump and aromatic dioxygenase, detoxification mechanisms that are triggered by the lead compound triclosan. These diphenyl ether-based InhA inhibitors do not require activation by the mycobacterial KatG enzyme, thereby circumventing the normal mechanism of resistance to the front line drug isoniazid (INH) and thus accounting for their activity against INH-resistant strains of MTB.

  15. Relationship between education and training activities and tuberculosis case detection in Fiji, 2008-2011.

    PubMed

    Delai, M Y; Gounder, S; Tayler-Smith, K; Van den Bergh, R; Harries, A D

    2012-12-21

    Due to concerns about under-reporting of the tuberculosis (TB) case burden in Fiji, efforts have been put into national training, education and awareness activities in the formal health sector and among village health workers, health volunteers and the community since 2010. There has been an absolute increase in TB registrations, and TB case notification rates during the period of training activities in 2010 (21.3 per 100 000 population) and 2011 (23.6/100 000) were significantly increased compared with TB case notification rates in 2008 (12.4/100 000) and 2009 (14.6/100 000), when no training activities took place (P < 0.01). These findings support the use of ongoing training efforts.

  16. Evaluation of the anti-mycobacterium tuberculosis activity and in vivo acute toxicity of Annona sylvatic

    PubMed Central

    2014-01-01

    Background The recent emergence of extensively multidrug-resistant Mycobacterium tuberculosis strains has further complicated the control of tuberculosis. There is an urgent need for the development of new molecular candidates antitubercular drugs. Medicinal plants have been an excellent source of leads for the development of drugs. The aim of this study was to evaluate the in vitro activity of 28 alcoholic extracts and essential oils of native and exotic Brazilian plants against Mycobacterium tuberculosis and to further study these extracts through chemical fractionation, the isolation of their constituents, and an evaluation of the in vivo acute toxicity of the active extracts. To the best of our knowledge this is the first chemical characterization, antituberculosis activity and acute toxicity evaluation of Annona sylvatica. Methods The anti-mycobacterial activity of these extracts and their constituent compounds was evaluated using the resazurin reduction microtiter assay (REMA). To investigate the acute toxicity of these extracts in vivo, female Swiss mice were treated with the extracts at doses of 500, 1000 and 2000 mg · kg-1 of body weight. The extracts were characterized by LC-MS, and the constituents were isolated and identified by chromatographic analysis of spectroscopic data. Results Of the 28 extracts, the methanol extract obtained from the leaves of Annona sylvatica showed anti-mycobacterial activity with an minimal inhibitory concentration (MIC) of 184.33 μg/mL, and the ethyl acetate fraction (EAF) resulting from liquid-liquid partitioning of the A. sylvatica extract showed an MIC of 115.2 μg/mL. The characterization of this extract by LC-MS identified flavonoids and acetogenins as its main constituents. The phytochemical study of the A. sylvatica EAF resulted in the isolation of quercetin, luteolin, and almunequin. Conclusions Among the compounds isolated from the EAF, luteolin and almunequin were the most promising, with MICs of 236.8

  17. Rifapentine is not more active than rifampin against chronic tuberculosis in guinea pigs.

    PubMed

    Dutta, Noton K; Illei, Peter B; Peloquin, Charles A; Pinn, Michael L; Mdluli, Khisimuzi E; Nuermberger, Eric L; Grosset, Jacques H; Karakousis, Petros C

    2012-07-01

    Rifamycins are key sterilizing drugs in the current treatment of active tuberculosis (TB). Daily dosing of rifapentine (P), a potent rifamycin with high intracellular accumulation, in place of rifampin (R) in the standard antitubercular regimen significantly shortens the duration of treatment needed to prevent relapse in a murine model of active TB. We undertook the current study to compare directly the activities of human-equivalent doses of P and R in a guinea pig model of chronic TB, in which bacilli are predominantly extracellular within human-like necrotic granulomas. Hartley strain guinea pigs were aerosol infected with ~200 bacilli of Mycobacterium tuberculosis H37Rv, and treatment given 5 days/week was initiated 6 weeks later. R at 100 mg/kg of body weight and P at 100 mg/kg were given orally alone or in combination with isoniazid (H) at 60 mg/kg and pyrazinamide (Z) at 300 mg/kg. Culture-positive relapse was assessed in subgroups of guinea pigs after completion of 1 and 2 months of treatment. Human-equivalent doses of R and P showed equivalent bactericidal activity when used alone and in combination therapy. In guinea pigs treated with rifampin, isoniazid, and pyrazinamide (RHZ) or PHZ, microbiological relapse occurred in the lungs of 8/10 animals treated for 1 month and in 0/10 animals treated for 2 months. Substitution of P for R in the standard antitubercular regimen did not shorten the time to cure in this guinea pig model of chronic TB. Data from ongoing clinical trials comparing the activity of these two drugs are awaited to determine the relevance of the guinea pig TB model in preclinical drug screening.

  18. Weekly Moxifloxacin and Rifapentine Is More Active Than the Denver Regimen in Murine Tuberculosis

    PubMed Central

    Rosenthal, Ian M.; Williams, Kathy; Tyagi, Sandeep; Vernon, Andrew A.; Peloquin, Charles A.; Bishai, William R.; Grosset, Jacques H.; Nuermberger, Eric L.

    2005-01-01

    Rationale: Treatment of tuberculosis with an efficacious once-weekly regimen would be a significant achievement in improving patient adherence. Currently, the only recommended once-weekly continuation phase regimen of isoniazid plus rifapentine (10 mg/kg) is inferior to standard twice-weekly therapy with isoniazid plus rifampin and is, therefore, restricted to non–high-risk patients. The substitution of moxifloxacin, a new 8-methoxyfluoroquinolone, for isoniazid and an increase in the dose of rifapentine could augment the activity of once-weekly regimens. Methods: To test this hypothesis we evaluated the sterilizing activity of improved once-weekly rifapentine-based continuation phase regimens in a murine model that mimics the treatment of high-risk patients with tuberculosis. The bactericidal activity of standard daily therapy and standard intermittent therapy (“Denver” regimen) was also assessed to evaluate the effect of intermittent drug administration during the initial phase of therapy. Results: After 2 mo of treatment, lung colony-forming unit counts were 1 log10 lower in mice treated with standard daily therapy than with the Denver regimen. During the continuation phase, the sterilizing activity of once-weekly moxifloxacin plus rifapentine (15 mg/kg) was significantly greater than that of the predominantly twice-weekly Denver regimen of isoniazid plus rifampin. No significant difference in sterilizing activity was detected between once-weekly isoniazid plus rifapentine (15 mg/kg) and the Denver regimen. Conclusions: These results suggest that the efficacy of the once-weekly isoniazid plus rifapentine continuation phase regimen can be increased by substituting moxifloxacin for isoniazid and by increasing the dose of rifapentine to a clinically acceptable level of 15 mg/kg. PMID:16141439

  19. Rifapentine Is Not More Active than Rifampin against Chronic Tuberculosis in Guinea Pigs

    PubMed Central

    Dutta, Noton K.; Illei, Peter B.; Peloquin, Charles A.; Pinn, Michael L.; Mdluli, Khisimuzi E.; Nuermberger, Eric L.; Grosset, Jacques H.

    2012-01-01

    Rifamycins are key sterilizing drugs in the current treatment of active tuberculosis (TB). Daily dosing of rifapentine (P), a potent rifamycin with high intracellular accumulation, in place of rifampin (R) in the standard antitubercular regimen significantly shortens the duration of treatment needed to prevent relapse in a murine model of active TB. We undertook the current study to compare directly the activities of human-equivalent doses of P and R in a guinea pig model of chronic TB, in which bacilli are predominantly extracellular within human-like necrotic granulomas. Hartley strain guinea pigs were aerosol infected with ∼200 bacilli of Mycobacterium tuberculosis H37Rv, and treatment given 5 days/week was initiated 6 weeks later. R at 100 mg/kg of body weight and P at 100 mg/kg were given orally alone or in combination with isoniazid (H) at 60 mg/kg and pyrazinamide (Z) at 300 mg/kg. Culture-positive relapse was assessed in subgroups of guinea pigs after completion of 1 and 2 months of treatment. Human-equivalent doses of R and P showed equivalent bactericidal activity when used alone and in combination therapy. In guinea pigs treated with rifampin, isoniazid, and pyrazinamide (RHZ) or PHZ, microbiological relapse occurred in the lungs of 8/10 animals treated for 1 month and in 0/10 animals treated for 2 months. Substitution of P for R in the standard antitubercular regimen did not shorten the time to cure in this guinea pig model of chronic TB. Data from ongoing clinical trials comparing the activity of these two drugs are awaited to determine the relevance of the guinea pig TB model in preclinical drug screening. PMID:22547623

  20. Structure-activity relationships of compounds targeting mycobacterium tuberculosis 1-deoxy-D-xylulose 5-phosphate synthase.

    PubMed

    Mao, Jialin; Eoh, Hyungjin; He, Rong; Wang, Yuehong; Wan, Baojie; Franzblau, Scott G; Crick, Dean C; Kozikowski, Alan P

    2008-10-01

    We report on a target-based approach to identify possible Mycobacterium tuberculosis DXS inhibitors from the structure of a known transketolase inhibitor. A small focused library of analogs was assembled in order to begin elucidating some meaningful structure-activity relationships of 3-(4-chloro-phenyl)-5-benzyl-4H-pyrazolo[1,5-a]pyrimidin-7-one. Ultimately we found that 2-methyl-3-(4-fluorophenyl)-5-(4-methoxy-phenyl)-4H-pyrazolo[1,5-a]pyrimidin-7-one, although still weak, was able to inhibit M. tuberculosis DXS with an IC(50) of 10.6 microM.

  1. Etanercept Exacerbates Inflammation and Pathology in a Rabbit Model of Active Pulmonary Tuberculosis

    PubMed Central

    Tsenova, Liana; O'Brien, Paul; Holloway, Jennifer; Peixoto, Blas; Soteropoulos, Patricia; Fallows, Dorothy; Subbian, Selvakumar

    2014-01-01

    Treatment of chronic inflammatory diseases with tumor necrosis factor alpha (TNF-α) antagonists has been associated with increased risk of tuberculosis (TB). We examined the usefulness of the rabbit model of active pulmonary TB for studying the impact of the human immune modulatory reagent etanercept on the host immune response. Control of Mycobacterium tuberculosis (Mtb) infection, disease pathology, and the global transcriptional response in Mtb-infected lungs of rabbits were studied. Etanercept treatment exacerbated disease pathology and reduced bacillary control in the lungs, compared with infected untreated animals. Reduced collagen and fibrin deposition in the granulomas was associated with significant downregulation of the collagen metabolism and fibrosis network genes and upregulation of genes in the inflammatory response and cell recruitment networks in the lungs of etanercept treated, compared with untreated rabbits. Our results suggest that targeting the TNF-α signaling pathway disrupts the tissue remodeling process, which is required for the formation and maintenance of well-differentiated granulomas and for control of Mtb growth in the lungs. These results validate the use of the rabbit model for investigating the impact of selected human immune modulatory drugs, such as a TNF-α antagonist, on the host immune response and pathogenesis in TB. PMID:24831609

  2. Host Protein Biomarkers Identify Active Tuberculosis in HIV Uninfected and Co-infected Individuals

    PubMed Central

    Achkar, Jacqueline M.; Cortes, Laetitia; Croteau, Pascal; Yanofsky, Corey; Mentinova, Marija; Rajotte, Isabelle; Schirm, Michael; Zhou, Yiyong; Junqueira-Kipnis, Ana Paula; Kasprowicz, Victoria O.; Larsen, Michelle; Allard, René; Hunter, Joanna; Paramithiotis, Eustache

    2015-01-01

    Biomarkers for active tuberculosis (TB) are urgently needed to improve rapid TB diagnosis. The objective of this study was to identify serum protein expression changes associated with TB but not latent Mycobacterium tuberculosis infection (LTBI), uninfected states, or respiratory diseases other than TB (ORD). Serum samples from 209 HIV uninfected (HIV−) and co-infected (HIV+) individuals were studied. In the discovery phase samples were analyzed via liquid chromatography and mass spectrometry, and in the verification phase biologically independent samples were analyzed via a multiplex multiple reaction monitoring mass spectrometry (MRM-MS) assay. Compared to LTBI and ORD, host proteins were significantly differentially expressed in TB, and involved in the immune response, tissue repair, and lipid metabolism. Biomarker panels whose composition differed according to HIV status, and consisted of 8 host proteins in HIV− individuals (CD14, SEPP1, SELL, TNXB, LUM, PEPD, QSOX1, COMP, APOC1), or 10 host proteins in HIV+ individuals (CD14, SEPP1, PGLYRP2, PFN1, VASN, CPN2, TAGLN2, IGFBP6), respectively, distinguished TB from ORD with excellent accuracy (AUC = 0.96 for HIV− TB, 0.95 for HIV+ TB). These results warrant validation in larger studies but provide promise that host protein biomarkers could be the basis for a rapid, blood-based test for TB. PMID:26501113

  3. The association between sterilizing activity and drug distribution into tuberculosis lesions

    PubMed Central

    Prideaux, Brendan; Via, Laura E.; Zimmerman, Matthew D.; Eum, Seokyong; Sarathy, Jansy; O’Brien, Paul; Chen, Chao; Kaya, Firat; Weiner, Danielle M.; Chen, Pei-Yu; Song, Taeksun; Lee, Myungsun; Shim, TaeSun; Cho, Jeong Su; Kim, Wooshik; Cho, Sang Nae; Olivier, Kenneth N.; Barry, Clifton E.; Dartois, Véronique

    2015-01-01

    Finding new treatment-shortening antibiotics to improve cure rates and curb the alarming emergence of drug resistance is the major objective of tuberculosis (TB) drug development. Using a MALDI mass spectrometry imaging suite in a biosafety containment facility, we show that the key sterilizing drugs rifampicin and pyrazinamide efficiently penetrate the sites of TB infection in lung lesions. Rifampicin even accumulates in necrotic caseum, a critical lesion site where persisting tubercle bacilli reside1. In contrast, moxifloxacin which is active in vitro against persisters, a sub-population of Mycobacterium tuberculosis that persists in specific niches under drug pressure, and achieved treatment shortening in mice2, does not diffuse well in caseum, concordant with its failure to shorten therapy in recent clinical trials. We also suggest that such differential spatial distribution and kinetics of accumulation in lesions may create temporal and spatial windows of monotherapy in specific niches, allowing the gradual development of multidrug resistant TB. We propose an alternative working model to prioritize new antibiotic regimens based on quantitative and spatial distribution of TB drugs in the major lesion types found in human lungs. The finding that lesion penetration contributes to treatment outcome has wide implications for TB. PMID:26343800

  4. ATP-dependent motor activity of the transcription termination factor Rho from Mycobacterium tuberculosis.

    PubMed

    D'Heygère, François; Schwartz, Annie; Coste, Franck; Castaing, Bertrand; Boudvillain, Marc

    2015-07-13

    The bacterial transcription termination factor Rho-a ring-shaped molecular motor displaying directional, ATP-dependent RNA helicase/translocase activity-is an interesting therapeutic target. Recently, Rho from Mycobacterium tuberculosis (MtbRho) has been proposed to operate by a mechanism uncoupled from molecular motor action, suggesting that the manner used by Rho to dissociate transcriptional complexes is not conserved throughout the bacterial kingdom. Here, however, we demonstrate that MtbRho is a bona fide molecular motor and directional helicase which requires a catalytic site competent for ATP hydrolysis to disrupt RNA duplexes or transcription elongation complexes. Moreover, we show that idiosyncratic features of the MtbRho enzyme are conferred by a large, hydrophilic insertion in its N-terminal 'RNA binding' domain and by a non-canonical R-loop residue in its C-terminal 'motor' domain. We also show that the 'motor' domain of MtbRho has a low apparent affinity for the Rho inhibitor bicyclomycin, thereby contributing to explain why M. tuberculosis is resistant to this drug. Overall, our findings support that, in spite of adjustments of the Rho motor to specific traits of its hosting bacterium, the basic principles of Rho action are conserved across species and could thus constitute pertinent screening criteria in high-throughput searches of new Rho inhibitors.

  5. Potential novel markers to discriminate between active and latent tuberculosis infection in Chinese individuals.

    PubMed

    Bai, Xue-juan; Liang, Yan; Yang, You-rong; Feng, Jin-dong; Luo, Zhan-peng; Zhang, Jun-Xian; Wu, Xue-qiong

    2016-02-01

    Latent tuberculosis infection (LTBI) constitutes the main reservoir for reactivation tuberculosis. The finding of potential biomarkers for differentiating between TB and LTBI is very necessary. In this study, the immunological characteristics and potential diagnostic utility of Rv2029c, Rv2628 and Rv1813c proteins were assessed. These three proteins stimulated PBMCs from ELISPOT-positive LTBI subjects produced higher levels of IFN-γ in comparison with TB patients and ELISPOT-negative healthy subjects (p<0.05). BCG vaccination and non-TB respiratory disease had little influence on the immunological responses of Rv2029c and Rv2628 proteins (p>0.05). The LTBI diagnostic performance of Rv2029c was higher than Rv2628 and Rv1813c by ROC evaluation. But Rv2628 had much higher specificity than Rv2029c in active TB patients and uninfected healthy subjects. The IgG level against Rv1813c was higher in the TB group than in LTBI and uninfected healthy subjects (p<0.05). These results suggest that T cell response to Rv2628 and antibody against Rv1813c might be applicable as biomarkers to distinguish TB from LTBI and uninfected individuals.

  6. Tuberculosis versus vasculitis.

    PubMed

    Baig, Zahid Farooq; Raja, Khalid Mahmood; Abbas, Fahad

    2014-01-01

    Vasculitis (Wegeners Granulomatosis and Microscopic Polyangiitis) and Tuberculosis share many features including constitutional symptoms and respiratory tract involvement. The presence of kidney involvement with new onset azotaemia and active urine sediment support the diagnosis of vasculitis. We describe two cases that were diagnosed to be suffering from tuberculosis and placed on anti-tuberculosis therapy. On further workup they were found to be suffering from pauci- immune glomerulonephritis and recovered well with treatment.

  7. Genome-Wide Expression Profiling Identifies Type 1 Interferon Response Pathways in Active Tuberculosis

    PubMed Central

    Ottenhoff, Tom H. M.; Zhang, Mingzi M.; Wong, Hazel E. E.; Sahiratmadja, Edhyana; Khor, Chiea Chuen; Alisjahbana, Bachti; van Crevel, Reinout; Marzuki, Sangkot; Seielstad, Mark; van de Vosse, Esther; Hibberd, Martin L.

    2012-01-01

    Tuberculosis (TB), caused by Mycobacterium tuberculosis (M.tb), remains the leading cause of mortality from a single infectious agent. Each year around 9 million individuals newly develop active TB disease, and over 2 billion individuals are latently infected with M.tb worldwide, thus being at risk of developing TB reactivation disease later in life. The underlying mechanisms and pathways of protection against TB in humans, as well as the dynamics of the host response to M.tb infection, are incompletely understood. We carried out whole-genome expression profiling on a cohort of TB patients longitudinally sampled along 3 time-points: during active infection, during treatment, and after completion of curative treatment. We identified molecular signatures involving the upregulation of type-1 interferon (α/β) mediated signaling and chronic inflammation during active TB disease in an Indonesian population, in line with results from two recent studies in ethnically and epidemiologically different populations in Europe and South Africa. Expression profiles were captured in neutrophil-depleted blood samples, indicating a major contribution of lymphocytes and myeloid cells. Expression of type-1 interferon (α/β) genes mediated was also upregulated in the lungs of M.tb infected mice and in infected human macrophages. In patients, the regulated gene expression-signature normalized during treatment, including the type-1 interferon mediated signaling and a concurrent opposite regulation of interferon-gamma. Further analysis revealed IL15RA, UBE2L6 and GBP4 as molecules involved in the type-I interferon response in all three experimental models. Our data is highly suggestive that the innate immune type-I interferon signaling cascade could be used as a quantitative tool for monitoring active TB disease, and provide evidence that components of the patient’s blood gene expression signature bear similarities to the pulmonary and macrophage response to mycobacterial infection

  8. Comparison of tuberculin skin testing and T-SPOT.TB for diagnosis of latent and active tuberculosis.

    PubMed

    Simsek, Hulya; Alpar, Sibel; Ucar, Nazire; Aksu, Funda; Ceyhan, Ismail; Gözalan, Aysegul; Cesur, Salih; Ertek, Mustafa

    2010-03-01

    The T-SPOT.TB test does not cross-react with Bacille Calmette-Guérin or most non-tuberculosis mycobacterium species, and is based on IFN-gamma responses to Mycobacterium tuberculosis-specific antigens. The objective of this study was to compare tuberculin skin test (TST) with T-SPOT.TB results used in the diagnosis of active tuberculosis (TB) as well as latent tuberculosis infection (LTBI). A total of 136 subjects participated in three different groups (47 patients with active pulmonary TB, 47 healthy persons without M. tuberculosis exposure, and 42 hospital members with a history of close contact with active TB patients). The T-SPOT.TB sensitivity (83.0%) and the negative predictive value (NPV) (82.6%) in the diagnosis of active TB were significantly higher than those of TST. The sensitivity and NPV of the TST were 38.3 and 60.8%, respectively. The T-SPOT.TB specificity (80.9%) and positive predictive value (81.3%) were lower than those of TST (95.7 and 90.0%, respectively). The performance of T-SPOT.TB and TST for diagnosing LTBI was the same (54.8%). T-SPOT.TB was superior in terms of sensitivity (83.0%); TST detected only 18, whereas T-SPOT.TB test detected 39 out of 47 patients with active TB. T-SPOT.TB is thought to have better performance than TST due to false-negative results in diagnosing active TB. However, it is considered that large prospective longitudinal studies are needed for diagnosing LTBI.

  9. Anti-tubercular and antioxidant activities of C-glycosyl carbonic anhydrase inhibitors: towards the development of novel chemotherapeutic agents against Mycobacterium tuberculosis.

    PubMed

    Zaro, María J; Bortolotti, Ana; Riafrecha, Leonardo E; Concellón, Analía; Morbidoni, Héctor R; Colinas, Pedro A

    2016-12-01

    During the treatment of tuberculosis infection, oxidative stress due to anti-tubercular drugs may result in tissue inflammation. It was suggested that treatment with antioxidant drugs could be beneficial as an adjunct to anti-tuberculosis drug therapy. Recently our group has shown that several C-glycosides are inhibitors of Mycobacterium tuberculosis β-carbonic anhydrases (CAs, EC 4.2.1.1). In an effort to develop novel chemotherapeutic agents against tuberculosis, the anti-tubercular and antioxidant activities of a series of C-glycosides containing the phenol or the methoxyaryl moiety were studied. Many compounds showed inhibition of growth of M. tuberculosis H37Rv strain and good antioxidant ability. A glycomimetic incorporating the 3-hydroxyphenyl moiety showed the best activity profile and therefore this functionality represents lead for the development of novel anti-tubercular agents with dual mechanisms of action.

  10. "Secular light curves of 25 members of the themis family of asteroids, suspected of low level cometary activity"

    NASA Astrophysics Data System (ADS)

    Ferrín, Ignacio; Pérez, Martín; Rendón, Juan

    2017-03-01

    From 1996-2015 sixteen main belt asteroids were discovered exhibiting cometary activity (less than one per year), all of them during searches at the telescope. In this work we will explore another way to discover them. We reduced 192.016 magnitude observations of 165 asteroids of the Themis family, using data from the astrometric-photometric database of the Minor Planet Center, MPCOBS, and measuring the absolute magnitudes from the phase plots. 25 objects of 165 (15.2%), exhibited bumps or enhancements in brightness that might indicate low level cometary activity. Since activity repeats at the same place in different orbits and in many occasions is centered at perihelion, activity might be due to water ice sublimation. We do not find support for a correlation between short rotational periods (3-4 h), and cometary activity, although we find an excess of fast rotators.

  11. Characterization of Antibacterial and Hemolytic Activity of Synthetic Pandinin 2 Variants and Their Inhibition against Mycobacterium tuberculosis

    PubMed Central

    Rodríguez, Alexis; Villegas, Elba; Montoya-Rosales, Alejandra; Rivas-Santiago, Bruno; Corzo, Gerardo

    2014-01-01

    The contention and treatment of Mycobacterium tuberculosis and other bacteria that cause infectious diseases require the use of new type of antibiotics. Pandinin 2 (Pin2) is a scorpion venom antimicrobial peptide highly hemolytic that has a central proline residue. This residue forms a structural “kink” linked to its pore-forming activity towards human erythrocytes. In this work, the residue Pro14 of Pin2 was both substituted and flanked using glycine residues (P14G and P14GPG) based on the low hemolytic activities of antimicrobial peptides with structural motifs Gly and GlyProGly such as magainin 2 and ponericin G1, respectively. The two Pin2 variants showed antimicrobial activity against E. coli, S. aureus, and M. tuberculosis. However, Pin2 [GPG] was less hemolytic (30%) than that of Pin2 [G] variant. In addition, based on the primary structure of Pin2 [G] and Pin2 [GPG], two short peptide variants were designed and chemically synthesized keeping attention to their physicochemical properties such as hydrophobicity and propensity to adopt alpha-helical conformations. The aim to design these two short antimicrobial peptides was to avoid the drawback cost associated to the synthesis of peptides with large sequences. The short Pin2 variants named Pin2 [14] and Pin2 [17] showed antibiotic activity against E. coli and M. tuberculosis. Besides, Pin2 [14] presented only 25% of hemolysis toward human erythrocytes at concentrations as high as 100 µM, while the peptide Pin2 [17] did not show any hemolytic effect at the same concentration. Furthermore, these short antimicrobial peptides had better activity at molar concentrations against multidrug resistance M. tuberculosis than that of the conventional antibiotics ethambutol, isoniazid and rifampicin. Therefore, Pin2 [14] and Pin2 [17] have the potential to be used as an alternative antibiotics and anti-tuberculosis agents with reduced hemolytic effects. PMID:25019413

  12. Characterization of antibacterial and hemolytic activity of synthetic pandinin 2 variants and their inhibition against Mycobacterium tuberculosis.

    PubMed

    Rodríguez, Alexis; Villegas, Elba; Montoya-Rosales, Alejandra; Rivas-Santiago, Bruno; Corzo, Gerardo

    2014-01-01

    The contention and treatment of Mycobacterium tuberculosis and other bacteria that cause infectious diseases require the use of new type of antibiotics. Pandinin 2 (Pin2) is a scorpion venom antimicrobial peptide highly hemolytic that has a central proline residue. This residue forms a structural "kink" linked to its pore-forming activity towards human erythrocytes. In this work, the residue Pro14 of Pin2 was both substituted and flanked using glycine residues (P14G and P14GPG) based on the low hemolytic activities of antimicrobial peptides with structural motifs Gly and GlyProGly such as magainin 2 and ponericin G1, respectively. The two Pin2 variants showed antimicrobial activity against E. coli, S. aureus, and M. tuberculosis. However, Pin2 [GPG] was less hemolytic (30%) than that of Pin2 [G] variant. In addition, based on the primary structure of Pin2 [G] and Pin2 [GPG], two short peptide variants were designed and chemically synthesized keeping attention to their physicochemical properties such as hydrophobicity and propensity to adopt alpha-helical conformations. The aim to design these two short antimicrobial peptides was to avoid the drawback cost associated to the synthesis of peptides with large sequences. The short Pin2 variants named Pin2 [14] and Pin2 [17] showed antibiotic activity against E. coli and M. tuberculosis. Besides, Pin2 [14] presented only 25% of hemolysis toward human erythrocytes at concentrations as high as 100 µM, while the peptide Pin2 [17] did not show any hemolytic effect at the same concentration. Furthermore, these short antimicrobial peptides had better activity at molar concentrations against multidrug resistance M. tuberculosis than that of the conventional antibiotics ethambutol, isoniazid and rifampicin. Therefore, Pin2 [14] and Pin2 [17] have the potential to be used as an alternative antibiotics and anti-tuberculosis agents with reduced hemolytic effects.

  13. Plasma drug activity in patients on treatment for multidrug-resistant tuberculosis.

    PubMed

    Mpagama, Stellah G; Ndusilo, Norah; Stroup, Suzanne; Kumburu, Happiness; Peloquin, Charles A; Gratz, Jean; Houpt, Eric R; Kibiki, Gibson S; Heysell, Scott K

    2014-01-01

    Little is known about plasma drug concentrations relative to quantitative susceptibility in patients with multidrug-resistant tuberculosis (MDR-TB). We previously described a TB drug activity (TDA) assay that determines the ratio of the time to detection of plasma-cocultured Mycobacterium tuberculosis versus control growth in a Bactec MGIT system. Here, we assess the activity of individual drugs in a typical MDR-TB regimen using the TDA assay. We also examined the relationship of the TDA to the drug concentration at 2 h (C2) and the MICs among adults on a MDR-TB regimen in Tanzania. These parameters were also compared to the treatment outcome of sputum culture conversion. Individually, moxifloxacin yielded superior TDA results versus ofloxacin, and only moxifloxacin and amikacin yielded TDAs equivalent to a -2-log killing. In the 25 patients enrolled on a regimen of kanamycin, levofloxacin, ethionamide, pyrazinamide, and cycloserine, the C2 values were found to be below the expected range for levofloxacin in 13 (52%) and kanamycin in 10 (40%). Three subjects with the lowest TDA result (<1.5, a finding indicative of poor killing) had significantly lower kanamycin C2/MIC ratios than subjects with a TDA of ≥1.5 (9.8 ± 8.7 versus 27.0 ± 19.1; P = 0.04). The mean TDAs were 2.52 ± 0.76 in subjects converting to negative in ≤2 months and 1.88 ± 0.57 in subjects converting to negative in >2 months (P = 0.08). In Tanzania, MDR-TB drug concentrations were frequently low, and a wide concentration/MIC range was observed that affected plasma drug activity ex vivo. An opportunity exists for pharmacokinetic optimization in current MDR-TB regimens, which may improve treatment response.

  14. Highly active antiretroviral therapy and tuberculosis control in Africa: synergies and potential.

    PubMed Central

    Harries, Anthony D.; Hargreaves, Nicola J.; Chimzizi, Rehab; Salaniponi, Felix M.

    2002-01-01

    HIV/AIDS (human immunodeficiency virus/acquired immunodeficiency syndrome) and TB (tuberculosis) are two of the world's major pandemics, the brunt of which falls on sub-Saharan Africa. Efforts aimed at controlling HIV/AIDS have largely focused on prevention, little attention having been paid to care. Work on TB control has concentrated on case detection and treatment. HIV infection has complicated the control of tuberculosis. There is unlikely to be a decline in the number of cases of TB unless additional strategies are developed to control both this disease and HIV simultaneously. Such strategies would include active case-finding in situations where TB transmission is high, the provision of a package of care for HIV-related illness, and the application of highly active antiretroviral therapy. The latter is likely to have the greatest impact, but for this therapy to become more accessible in Africa the drugs would have to be made available through international support and a programme structure would have to be developed for its administration. It could be delivered by means of a structure based on the five-point strategy called DOTS, which has been adopted for TB control. However, it may be unrealistic to give TB control programmes the responsibility for running such a programme. A better approach might be to deliver highly active antiretroviral therapy within a comprehensive HIV/AIDS management strategy complementing the preventive work already being undertaken by AIDS control programmes. TB programmes could contribute towards the development and implementation of this strategy. PMID:12132003

  15. In Vivo Molecular Dissection of the Effects of HIV-1 in Active Tuberculosis.

    PubMed

    Bell, Lucy C K; Pollara, Gabriele; Pascoe, Mellissa; Tomlinson, Gillian S; Lehloenya, Rannakoe J; Roe, Jennifer; Meldau, Richard; Miller, Robert F; Ramsay, Alan; Chain, Benjamin M; Dheda, Keertan; Noursadeghi, Mahdad

    2016-03-01

    Increased risk of tuberculosis (TB) associated with HIV-1 infection is primarily attributed to deficient T helper (Th)1 immune responses, but most people with active TB have robust Th1 responses, indicating that these are not sufficient to protect against disease. Recent findings suggest that favourable outcomes following Mycobacterium tuberculosis infection arise from finely balanced inflammatory and regulatory pathways, achieving pathogen control without immunopathology. We hypothesised that HIV-1 and antiretroviral therapy (ART) exert widespread changes to cell mediated immunity, which may compromise the optimal host protective response to TB and provide novel insights into the correlates of immune protection and pathogenesis. We sought to define these effects in patients with active TB by transcriptional profiling of tuberculin skin tests (TST) to make comprehensive molecular level assessments of in vivo human immune responses at the site of a standardised mycobacterial challenge. We showed that the TST transcriptome accurately reflects the molecular pathology at the site of human pulmonary TB, and used this approach to investigate immune dysregulation in HIV-1/TB co-infected patients with distinct clinical phenotypes associated with TST reactivity or anergy and unmasking TB immune reconstitution inflammatory syndrome (IRIS) after initiation of ART. HIV-1 infected patients with positive TSTs exhibited preserved Th1 responses but deficient immunoregulatory IL10-inducible responses. Those with clinically negative TSTs revealed profound anergy of innate as well as adaptive immune responses, except for preservation of type 1 interferon activity, implicated in impaired anti-mycobacterial immunity. Patients with unmasking TB IRIS showed recovery of Th1 immunity to normal levels, but exaggerated Th2-associated responses specifically. These mechanisms of immune dysregulation were localised to the tissue microenvironment and not evident in peripheral blood. TST

  16. Polymorphisms in the RANTES gene increase susceptibility to active tuberculosis in Tunisia.

    PubMed

    Ben-Selma, Walid; Harizi, Hedi; Bougmiza, Iheb; Ben Kahla, Imen; Letaief, Mahmoud; Boukadida, Jalel

    2011-10-01

    RANTES plays a pivotal role in attracting and activating various leukocyte populations that control Mycobacterium tuberculosis infection. The present study investigated the relationship between the RANTES polymorphisms (-28C/G; rs2280788, and -403G/A; rs2107538) and susceptibility to active tuberculosis (TB) in Tunisian populations. A total of 168 patients with pulmonary TB (pTB), 55 with extrapulmonary TB (epTB), and 150 control subjects were studied. Genotype analyses were carried out using polymerase chain reaction-restriction fragment length polymorphism method. We found that the -28 GG genotype was significantly associated with susceptibility to pTB (odds ratio [OR]=11.19; 95% confidence intervals [CI], 5.14-25; P corrected for the number of genotypes [Pc]=10(-8)) and epTB (OR=11.67; 95% CI, 4.74-29.33; Pc=10(-8)). However, the -28 CC genotype was found to be significantly associated with resistance to pTB (OR=0.08; 95% CI, 0.04-0.16; Pc=10(-8)) and epTB development (OR=0.11; 95% CI, 0.05-0.27; Pc=10(-8)). -403A allele was associated with increased risk development of epTB (OR=2.21; 95% CI, 1.18-4.14; p=0.007). G-G and A-C haplotypes and the AG/GC diplotype were associated with increase susceptibility to pTB (OR=7.88, 95% CI, 5.38-11.55; Pc=3.10(-8); OR=2.32, 95% CI, 1.32-4.11; Pc=3.10(-3); OR=13.26, 95% CI, 6.06-29.89; Pc=3.10(-8); respectively) and epTB (OR=6.64, 95% CI, 4-11.05; Pc=3.10(-8); OR=2.6, 95% CI, 1.26-5.35; Pc=12.10(-3); OR=11.26, 95% CI, 4.44-29.28; Pc=3.10(-8); respectively). Collectively, our findings suggested an association of the RANTES -28C/G and -403G/A functional polymorphisms with susceptibility to Mycobacterium tuberculosis infection in Tunisian populations.

  17. Tuberculosis among Children in Alaska.

    ERIC Educational Resources Information Center

    Gessner, Bradford D.

    1997-01-01

    The incidence of tuberculosis among Alaskan children under 15 was more than twice the national rate, with Alaska Native children showing a much higher incidence. Children with household exposure to adults with active tuberculosis had a high risk of infection. About 22 percent of pediatric tuberculosis cases were identified through school…

  18. Mechanistic insights on immunosenescence and chronic immune activation in HIV-tuberculosis co-infection

    PubMed Central

    Shankar, Esaki M; Velu, Vijayakumar; Kamarulzaman, Adeeba; Larsson, Marie

    2015-01-01

    Immunosenescence is marked by accelerated degradation of host immune responses leading to the onset of opportunistic infections, where senescent T cells show remarkably higher ontogenic defects as compared to healthy T cells. The mechanistic association between T-cell immunosenescence and human immunodeficiency virus (HIV) disease progression, and functional T-cell responses in HIV-tuberculosis (HIV-TB) co-infection remains to be elaborately discussed. Here, we discussed the association of immunosenescence and chronic immune activation in HIV-TB co-infection and reviewed the role played by mediators of immune deterioration in HIV-TB co-infection necessitating the importance of designing therapeutic strategies against HIV disease progression and pathogenesis. PMID:25674514

  19. Active tuberculosis among Iraqi schoolchildren with positive skin tests and their household contacts.

    PubMed

    Al Kubaisy, W; Al Dulayme, A; Hashim, D S

    2003-07-01

    In a prospective cohort study in Iraq, schoolchildren with a positive tuberculin skin test during the nationwide survey in 2000 were followed up in 2002 to determine prevalence of latent tuberculosis (TB) infection and risk factors among household contacts. Of 205 children, 191 remained skin-test positive in 2002. Based on X-ray and clinical examination, 9 children (4.4%) were active TB cases. Among 834 household contacts, there were 144 new TB cases, giving a cumulative incidence of 17.3%. Risk factors for TB among household contacts were: age > or = 15 years; technical/professional job; smoking; low body mass index; diabetes mellitus; steroid therapy; and closeness of contact with the index cases. Based on past history of TB in index children and their contacts, 77.2% of new TB cases were attributable to household contacts.

  20. [Surgery of late complications of previous active treatment of lung tuberculosis with extrapleural plombage].

    PubMed

    Teschner, M

    1998-02-01

    Between January 1984 and February 1997 10 patients with late complications of a former active collapse therapy were operated. In case of our patients between 1943 and 1960 the collaps therapy was carried out with the extrapleural instillation of plombs for therapy of pulmonary tuberculosis. At present main complications were infections of plombs with pleurobronchial and pleurocutaneus fistulas and perforation of plombs. By all patients both extirpation and pleurectomy were necessary. In case of 5 patients additionally lung resection was required, in case of 3 patients a thoracoplasty and by 1 patient a myoplasty. Although there are considerable destructions of lung parenchym in a part the results of long-term follow up are satisfactory: 6 patients are so far without complaints; only 1 patient died 10 years postoperative. Prerequisite for a successful therapy are the knowledge of the surgical methods of the collaps area, the used materials, the pathomorphological pulmonary changes and the good cooperation between pneumologists and thoracic surgeons.

  1. Prevalence of Pulmonary Tuberculosis among Prison Inmates in Ethiopia, a Cross-Sectional Study

    PubMed Central

    Ali, Solomon; Haileamlak, Abraham; Wieser, Andreas; Pritsch, Michael; Heinrich, Norbert; Loscher, Thomas; Hoelscher, Michael; Rachow, Andrea

    2015-01-01

    Setting Tuberculosis (TB) is one of the major health problems in prisons. Objective This study was done to assess the prevalence and determinants of active tuberculosis in Ethiopian prisons. Design A cross-sectional study was conducted from January 2013 to December 2013 in 13 zonal prisons. All incarcerated inmates underwent TB symptom screening according to WHO criteria. From identified TB-suspects two sputum samples were analyzed using smear microscopy and solid culture. A standardized questionnaire assessing TB risk factors was completed for each TB suspect. Results 765 (4.9%) TB suspects were identified among 15,495 inmates. 51 suspects were already on anti-TB treatment (6.67%) and 20 (2.8%) new culture-confirmed TB cases were identified in the study, resulting in an overall TB prevalence of 458.1/100,000 (95%CI: 350-560/100,000). Risk factors for active TB were alcohol consumption, contact with a TB case before incarceration and no window in prison cell. HIV prevalence was not different between TB suspects and active TB cases. Further, the TB burden in prisons increased with advancing distance from the capital Addis Ababa. Conclusions The overall TB prevalence in Ethiopian prisons was high and extremely variable among different prisons. TB risk factors related to conditions of prison facilities and the impact of implemented TB control measures need to be further studied in order to improve TB control among inmates. PMID:26641654

  2. Predictive value of the tuberculin skin test and QuantiFERON-tuberculosis Gold In-Tube test for development of active tuberculosis in hemodialysis patients

    PubMed Central

    Seyhan, Ekrem Cengiz; Gunluoglu, Gulşah; Gunluoglu, Mehmet Zeki; Tural, Seda; Sökücü, Sinem

    2016-01-01

    BACKGROUND: Hemodialysis (HD) patients are at increased risk of reactivation of latent tuberculosis infection (LTBI) compared with the general population. QuantiFERON-TB Gold (QFT-G) for LTBI detection is more promising than tuberculin skin test (TST) in HD patients. AIM: In our study, we evaluated the value of the TST and QFT-G In-Tube (QFG-IT) test in the development of active tuberculosis (TB), in the HD patients, and in healthy controls. METHODS: The study enrolled 95 HD patients and ninety age-matched, healthy controls. The TST and QFG-IT were performed. All the subjects were followed up 5 years for active TB disease. RESULTS: Compared to the healthy controls, a high prevalence of LTBI was found in the HD patients by QFG-IT (41% vs. 25%). However, no significant difference was detected by TST (32% vs. 31%). Four HD patients and one healthy control progressed to active TB disease within the 5-year follow-up. For active TB discovered subjects, QFG-IT was positive in all, but TST was positive in two (one patient and one healthy control). In HD patients; sensitivity, specificity, positive and negative predictive values of QFG-IT, and TST for active TB was 100% and 25%, 62% and 67%, 10%, and 3%, and 100% and 95%, respectively. Receiver operating curve analysis revealed that the results are significantly different (P = 0.04). CONCLUSION: QFG-IT test is a more useful diagnostic method than TST for detecting those who will progress to active TB in HD patients. PMID:27168859

  3. Cordilleran suspect terranes

    USGS Publications Warehouse

    Coney, P.J.; Jones, D.L.; Monger, J.W.H.

    1980-01-01

    Over 70% of the North American Cordillera is made up of 'suspect terranes'. Many of these geological provinces are certainly allochthonous to the North American continent and seem to have been swept from far reaches of the Pacific Ocean before collision and accretion into the Cordilleran margin mostly in Mesozoic to early Cenozoic time. ?? 1980 Nature Publishing Group.

  4. Structural analysis of the dodecameric proteasome activator PafE in Mycobacterium tuberculosis.

    PubMed

    Bai, Lin; Hu, Kuan; Wang, Tong; Jastrab, Jordan B; Darwin, K Heran; Li, Huilin

    2016-04-05

    The human pathogen Mycobacterium tuberculosis (Mtb) requires a proteasome system to cause lethal infections in mice. We recently found that proteasome accessory factor E (PafE, Rv3780) activates proteolysis by the Mtb proteasome independently of adenosine triphosphate (ATP). Moreover, PafE contributes to the heat-shock response and virulence of Mtb Here, we show that PafE subunits formed four-helix bundles similar to those of the eukaryotic ATP-independent proteasome activator subunits of PA26 and PA28. However, unlike any other known proteasome activator, PafE formed dodecamers with 12-fold symmetry, which required a glycine-XXX-glycine-XXX-glycine motif that is not found in previously described activators. Intriguingly, the truncation of the PafE carboxyl-terminus resulted in the robust binding of PafE rings to native proteasome core particles and substantially increased proteasomal activity, suggesting that the extended carboxyl-terminus of this cofactor confers suboptimal binding to the proteasome core particle. Collectively, our data show that proteasomal activation is not limited to hexameric ATPases in bacteria.

  5. Structural analysis of the dodecameric proteasome activator PafE in Mycobacterium tuberculosis

    DOE PAGES

    Bai, Lin; Hu, Kuan; Wang, Tong; ...

    2016-03-21

    Here, the human pathogen Mycobacterium tuberculosis (Mtb) requires a proteasome system to cause lethal infections in mice. We recently found that proteasome accessory factor E (PafE, Rv3780) activates proteolysis by the Mtb proteasome independently of adenosine triphosphate (ATP). Moreover, PafE contributes to the heat-shock response and virulence of Mtb. Here, we show that PafE subunits formed four-helix bundles similar to those of the eukaryotic ATP-independent proteasome activator subunits of PA26 and PA28. However, unlike any other known proteasome activator, PafE formed dodecamers with 12-fold symmetry, which required a glycine-XXX-glycine-XXX-glycine motif that is not found in previously described activators. Intriguingly, themore » truncation of the PafE carboxyl-terminus resulted in the robust binding of PafE rings to native proteasome core particles and substantially increased proteasomal activity, suggesting that the extended carboxyl-terminus of this cofactor confers suboptimal binding to the proteasome core particle. Collectively, our data show that proteasomal activation is not limited to hexameric ATPases in bacteria.« less

  6. Low-Income Parents' Warmth and Parent-Child Activities for Children with Disabilities, Suspected Delays and Biological Risks

    ERIC Educational Resources Information Center

    Eshbaugh, Elaine M.; Peterson, Carla A.; Wall, Shavaun; Carta, Judith J.; Luze, Gayle; Swanson, Mark; Jeon, Hyun-Joo

    2011-01-01

    Warm and responsive parenting is optimal for child development, but this style of parenting may be difficult for some parents to achieve. This study examines how parents' observed warmth and their reported frequency of parent-child activities were related to children's classifications as having biological risks or a range of disability indicators.…

  7. IL-10 down-regulates costimulatory molecules on Mycobacterium tuberculosis-pulsed macrophages and impairs the lytic activity of CD4 and CD8 CTL in tuberculosis patients.

    PubMed

    de la Barrera, S; Aleman, M; Musella, R; Schierloh, P; Pasquinelli, V; Garcia, V; Abbate, E; Sasiain, M del C

    2004-10-01

    Activation of T cells requires both TCR-specific ligation and costimulation through accessory molecules during T cell priming. IFNgamma is a key cytokine responsible for macrophage activation during Mycobacterium tuberculosis (Mtb) infection while IL-10 is associated with suppression of cell mediated immunity in intracellular infection. In this paper we evaluated the role of IFNgamma and IL-10 on the function of cytotoxic T cells (CTL) and on the modulation of costimulatory molecules in healthy controls and patients with active tuberculosis (TB). gamma-irradiated-Mtb (i-Mtb) induced IL-10 production from CD14(+) cells from TB patients. Moreover, CD3(+) T cells of patients with advanced disease also produced IL-10 after i-Mtb stimulation. In healthy donors, IL-10 decreased the lytic activity of CD4(+) and CD8(+) T cells whereas it increased gammadelta-mediated cytotoxicity. Furthermore, we found that the presence of IL-10 induced a loss of the alternative processing pathways of antigen presentation along with a down-regulation of the expression of costimulatory molecule expression on monocytes and macrophages from healthy individuals. Conversely, neutralization of endogenous IL-10 or addition of IFNgamma to either effector or target cells from TB patients induced a strong lytic activity mediated by CD8(+) CTL together with an up-regulation of CD54 and CD86 expression on target cells. Moreover, we observed that macrophages from TB patients could use alternative pathways for i-Mtb presentation. Taken together, our results demonstrate that the presence of IL-10 during Mtb infection might contribute to mycobacteria persistence inside host macrophages through a mechanism that involved inhibition of MHC-restricted cytotoxicity against infected macrophages.

  8. Symptom screening rules to identify active pulmonary tuberculosis: Findings from the Zambian South African Tuberculosis and HIV/AIDS Reduction (ZAMSTAR) trial prevalence surveys

    PubMed Central

    Claassens, M. M.; Floyd, S.; Ayles, H.; Beyers, N.

    2017-01-01

    Background High tuberculosis (TB) burden countries should consider systematic screening among adults in the general population. We identified symptom screening rules to be used in addition to cough ≥2 weeks, in a context where X-ray screening is not feasible, aiming to increase the sensitivity of screening while achieving a specificity of ≥85%. Methods We used 2010 Zambia South Africa Tuberculosis and HIV/AIDS Reduction (ZAMSTAR) survey data: a South African (SA) training dataset, a SA testing dataset for internal validation and a Zambian dataset for external validation. Regression analyses investigated relationships between symptoms or combinations of symptoms and active disease. Sensitivity and specificity were calculated for candidate rules. Results Among all participants, the sensitivity of using only cough ≥2 weeks as a screening rule was less than 25% in both SA and Zambia. The addition of any three of six TB symptoms (cough <2 weeks, night sweats, weight loss, fever, chest pain, shortness of breath), or 2 or more of cough <2 weeks, night sweats, and weight loss, increased the sensitivity to ~38%, while reducing specificity from ~95% to ~85% in SA and ~97% to ~92% in Zambia. Among HIV-negative adults, findings were similar in SA, whereas in Zambia the increase in sensitivity was relatively small (15% to 22%). Conclusion High TB burden countries should investigate cost-effective strategies for systematic screening: one such strategy could be to use our rule in addition to cough ≥2 weeks. PMID:28257424

  9. Synthesis and evaluation of M. tuberculosis salicylate synthase (MbtI) inhibitors designed to probe plasticity in the active site.

    PubMed

    Manos-Turvey, Alexandra; Cergol, Katie M; Salam, Noeris K; Bulloch, Esther M M; Chi, Gamma; Pang, Angel; Britton, Warwick J; West, Nicholas P; Baker, Edward N; Lott, J Shaun; Payne, Richard J

    2012-12-14

    Mycobacterium tuberculosis salicylate synthase (MbtI) catalyses the first committed step in the biosynthesis of mycobactin T, an iron-chelating siderophore essential for the virulence and survival of M. tuberculosis. Co-crystal structures of MbtI with members of a first generation inhibitor library revealed large inhibitor-induced rearrangements within the active site of the enzyme. This plasticity of the MbtI active site was probed via the preparation of a library of inhibitors based on a 2,3-dihydroxybenzoate scaffold with a range of substituted phenylacrylate side chains appended to the C3 position. Most compounds exhibited moderate inhibitory activity against the enzyme, with inhibition constants in the micromolar range, while several dimethyl ester variants possessed promising anti-tubercular activity in vitro.

  10. Activity of Medicinal Plant Extracts on Multiplication of Mycobacterium tuberculosis under Reduced Oxygen Conditions Using Intracellular and Axenic Assays

    PubMed Central

    Bhatter, Purva D.; Gupta, Pooja D.; Birdi, Tannaz J.

    2016-01-01

    Aim. Test the activity of selected medicinal plant extracts on multiplication of Mycobacterium tuberculosis under reduced oxygen concentration which represents nonreplicating conditions. Material and Methods. Acetone, ethanol and aqueous extracts of the plants Acorus calamus L. (rhizome), Ocimum sanctum L. (leaf), Piper nigrum L. (seed), and Pueraria tuberosa DC. (tuber) were tested on Mycobacterium tuberculosis H37Rv intracellularly using an epithelial cell (A549) infection model. The extracts found to be active intracellularly were further studied axenically under reducing oxygen concentrations. Results and Conclusions. Intracellular multiplication was inhibited ≥60% by five of the twelve extracts. Amongst these 5 extracts, in axenic culture, P. nigrum (acetone) was active under aerobic, microaerophilic, and anaerobic conditions indicating presence of multiple components acting at different levels and P. tuberosa (aqueous) showed bactericidal activity under microaerophilic and anaerobic conditions implying the influence of anaerobiosis on its efficacy. P. nigrum (aqueous) and A. calamus (aqueous and ethanol) extracts were not active under axenic conditions but only inhibited intracellular growth of Mycobacterium tuberculosis, suggesting activation of host defense mechanisms to mediate bacterial killing rather than direct bactericidal activity. PMID:26941797

  11. Modulation of the Activity of Mycobacterium tuberculosis LipY by Its PE Domain.

    PubMed

    Garrett, Christopher K; Broadwell, Lindsey J; Hayne, Cassandra K; Neher, Saskia B

    2015-01-01

    Mycobacterium tuberculosis harbors over 160 genes encoding PE/PPE proteins, several of which have roles in the pathogen's virulence. A number of PE/PPE proteins are secreted via Type VII secretion systems known as the ESX secretion systems. One PE protein, LipY, has a triglyceride lipase domain in addition to its PE domain. LipY can regulate intracellular triglyceride levels and is also exported to the cell wall by one of the ESX family members, ESX-5. Upon export, LipY's PE domain is removed by proteolytic cleavage. Studies using cells and crude extracts suggest that LipY's PE domain not only directs its secretion by ESX-5, but also functions to inhibit its enzymatic activity. Here, we attempt to further elucidate the role of LipY's PE domain in the regulation of its enzymatic activity. First, we established an improved purification method for several LipY variants using detergent micelles. We then used enzymatic assays to confirm that the PE domain down-regulates LipY activity. The PE domain must be attached to LipY in order to effectively inhibit it. Finally, we determined that full length LipY and the mature lipase lacking the PE domain (LipYΔPE) have similar melting temperatures. Based on our improved purification strategy and activity-based approach, we concluded that LipY's PE domain down-regulates its enzymatic activity but does not impact the thermal stability of the enzyme.

  12. Field evaluation of a blood based test for active tuberculosis in endemic settings.

    PubMed

    Khaliq, Aasia; Ravindran, Resmi; Hussainy, Syed Fahadulla; Krishnan, Viwanathan V; Ambreen, Atiqa; Yusuf, Noshin Wasim; Irum, Shagufta; Rashid, Abdul; Jamil, Muhammad; Zaffar, Fareed; Chaudhry, Muhammad Nawaz; Gupta, Puneet K; Akhtar, Muhammad Waheed; Khan, Imran H

    2017-01-01

    Over 9 million new active tuberculosis (TB) cases emerge each year from an enormous pool of 2 billion individuals latently infected with Mycobacterium tuberculosis (M. tb.) worldwide. About 3 million new TB cases per year are unaccounted for, and 1.5 million die. TB, however, is generally curable if diagnosed correctly and in a timely manner. The current diagnostic methods for TB, including state-of-the-art molecular tests, have failed in delivering the capacity needed in endemic countries to curtail this ongoing pandemic. Efficient, cost effective and scalable diagnostic approaches are critically needed. We report a multiplex TB serology panel using microbead suspension array containing a combination of 11 M.tb. antigens that demonstrated overall sensitivity of 91% in serum/plasma samples from TB patients confirmed by culture. Group wise sensitivities for sputum smear positive and negative patients were 95%, and 88%, respectively. Specificity of the test was 96% in untreated COPD patients and 91% in general healthy population. The sensitivity of this test is superior to that of the frontline sputum smear test with a comparable specificity (30-70%, and 93-99%, respectively). The multiplex serology test can be performed with scalability from 1 to 360 patients per day, and is amenable to automation for higher (1000s per day) throughput, thus enabling a scalable clinical work flow model for TB endemic countries. Taken together, the above results suggest that well defined antibody profiles in blood, analyzed by an appropriate technology platform, offer a valuable approach to TB diagnostics in endemic countries.

  13. Sterilizing Activity of Second-Line Regimens Containing TMC207 in a Murine Model of Tuberculosis

    PubMed Central

    Lounis, Nacer; Andries, Koen; Jarlier, Vincent

    2011-01-01

    Rationale The sterilizing activity of the regimen used to treat multidrug resistant tuberculosis (MDR TB) has not been studied in a mouse model. Objective and Methods Swiss mice were intravenously inoculated with 6 log10 of Mycobacterium tuberculosis (TB) strain H37Rv, treated with second-line drug combinations with or without the diarylquinoline TMC207, and then followed without treatment for 3 more months to determine relapse rates (modified Cornell model). Measurements Bactericidal efficacy was assessed by quantitative lung colony-forming unit (CFU) counts. Sterilizing efficacy was assessed by measuring bacteriological relapse rates 3 months after the end of treatment. Main Results The relapse rate observed after 12 months treatment with the WHO recommended MDR TB regimen (amikacin, ethionamide, pyrazinamide and moxifloxacin) was equivalent to the relapse rate observed after 6 months treatment with the recommended drug susceptible TB regimen (rifampin, isoniazid and pyrazinamide). When TMC207 was added to this MDR TB regimen, the treatment duration needed to reach the same relapse rate dropped to 6 months. A similar relapse rate was also obtained with a 6-month completely oral regimen including TMC207, moxifloxacin and pyrazinamide but excluding both amikacin and ethionamide. Conclusions In this murine model the duration of the WHO MDR TB treatment could be reduced to 12 months instead of the recommended 18–24 months. The inclusion of TMC207 in the WHO MDR TB treatment regimen has the potential to further shorten the treatment duration and at the same time to simplify treatment by eliminating the need to include an injectable aminoglycoside. PMID:21408613

  14. Tim-3 pathway affects NK cell impairment in patients with active tuberculosis.

    PubMed

    Wang, Feng; Hou, Hongyan; Wu, Shiji; Tang, Qing; Huang, Min; Yin, Botao; Huang, Jing; Liu, Weiyong; Mao, Lie; Lu, Yanfang; Sun, Ziyong

    2015-12-01

    Active tuberculosis (TB) patients show impaired NK cell function, and the underlying mechanism remains largely unknown. In this study, we confirmed the decrease in activation, cytokine secretion, and degranulation potential of NK cells in active TB patients. We further investigated whether coinhibitory receptor Tim-3 was involved with impairment of NK cells. Our results revealed that the expression of Tim-3 on NK cells was increased in active TB patients. Tim-3 expression was inversely correlated with IL-12-stimualted IFN-γ production. Moreover, blocking the Tim-3 pathway restored IFN-γ secretion and degranulation of NK cells. Blocking this pathway also increased NK cell cytotoxicity against K562 target cells, and improved the ability of NK cells to control Mtb growth in monocyte-derived macrophages. The Tim-3 expression on NK cells was also observed to be significantly decreased in TB patients post-treatment. In this study, we have identified that Tim-3 is involved with NK cell impairment in TB patients.

  15. Active Community-Based Case Finding for Tuberculosis With Limited Resources

    PubMed Central

    Karki, Bindu; Kittel, Guenter; Bolokon, Ignatius; Duke, Trevor

    2016-01-01

    Papua New Guinea is one of the 14 highest-burden countries for tuberculosis (TB) infection, but few community-based studies exist. We evaluated a low-cost method of active community case finding in Kabwum and Wasu in Morobe Province, Papua New Guinea. Over 3 months we visited 26 villages and screened adults and children for symptoms and signs of TB. Sputum samples were examined using smear microscopy. A total of 1700 people had chronic symptoms, of which 267 were suspicious for TB on further examination. Sputum from 230 symptomatic adults yielded 97 samples that were positive for acid-fast bacilli. In addition, 15 cases of extrapulmonary TB in adults and 17 cases of TB in children were identified. One hundred and thirty people were identified with active TB disease among the source population of approximately 17 000, giving an estimated prevalence of 765 per 100 000. One hundred and six (82%) cases were not previously diagnosed. The cost per case identified was US$146. It is feasible to conduct active community-based case finding and treatment initiation for TB with limited resources and in remote areas, and in Papua New Guinea the yield was high. Active case finding and follow-up of treatment in villages is needed to address the hidden burden of TB in Papua New Guinea and other high-burden Asia Pacific countries. PMID:28033717

  16. Microarray and network-based identification of functional modules and pathways of active tuberculosis.

    PubMed

    Bian, Zhong-Rui; Yin, Juan; Sun, Wen; Lin, Dian-Jie

    2017-02-08

    Diagnose of active tuberculosis (TB) is challenging and treatment response is also difficult to efficiently monitor. The aim of this study was to use an integrated analysis of microarray and network-based method to the samples from publically available datasets to obtain a diagnostic module set and pathways in active TB. Towards this goal, background protein-protein interactions (PPI) network was generated based on global PPI information and gene expression data, following by identification of differential expression network (DEN) from the background PPI network. Then, ego genes were extracted according to the degree features in DEN. Next, module collection was conducted by ego gene expansion based on EgoNet algorithm. After that, differential expression of modules between active TB and controls was evaluated using random permutation test. Finally, biological significance of differential modules was detected by pathways enrichment analysis based on Reactome database, and Fisher's exact test was implemented to extract differential pathways for active TB. Totally, 47 ego genes and 47 candidate modules were identified from the DEN. By setting the cutoff-criteria of gene size >5 and classification accuracy ≥0.9, 7 ego modules (Module 4, Module 7, Module 9, Module 19, Module 25, Module 38 and Module 43) were extracted, and all of them had the statistical significance between active TB and controls. Then, Fisher's exact test was conducted to capture differential pathways for active TB. Interestingly, genes in Module 4, Module 25, Module 38, and Module 43 were enriched in the same pathway, formation of a pool of free 40S subunits. Significant pathway for Module 7 and Module 9 was eukaryotic translation termination, and for Module 19 was nonsense mediated decay enhanced by the exon junction complex (EJC). Accordingly, differential modules and pathways might be potential biomarkers for treating active TB, and provide valuable clues for better understanding of molecular

  17. Predominance of modern Mycobacterium tuberculosis strains and active transmission of Beijing sublineage in Jayapura, Indonesia Papua.

    PubMed

    Chaidir, Lidya; Sengstake, Sarah; de Beer, Jessica; Oktavian, Antonius; Krismawati, Hana; Muhapril, Erfin; Kusumadewi, Inri; Annisa, Jessi; Anthony, Richard; van Soolingen, Dick; Achmad, Tri Hanggono; Marzuki, Sangkot; Alisjahbana, Bachti; van Crevel, Reinout

    2016-04-01

    Mycobacterium tuberculosis genotype distribution is different between West and Central Indonesia, but there are no data on the most Eastern part, Papua. We aimed to identify the predominant genotypes of M. tuberculosis responsible for tuberculosis in coastal Papua, their transmission, and the association with patient characteristics. A total of 199 M. tuberculosis isolates were collected. Spoligotyping was applied to describe the population structure of M. tuberculosis, lineage identification was performed using a combination of lineage-specific markers, and genotypic clusters were identified using a combination of 24-locus-MIRU-VNTR and spoligotyping. A high degree of genetic diversity was observed among isolates based on their spoligopatterns. Strains from modern lineage 4 made up almost half of strains (46.9%), being more abundant than the ancient lineage 1 (33.7%), and modern lineage 2 (19.4%). Thirty-five percent of strains belonged to genotypic clusters, especially strains in the Beijing genotype. Previous TB treatment and mutations associated with drug resistance were more common in patients infected with strains of the Beijing genotype. Papua shows a different distribution of M. tuberculosis genotypes compared to other parts of Indonesia. Clustering and drug resistance of modern strains recently introduced to Papua may contribute to the high tuberculosis burden in this region.

  18. Untreated Active Tuberculosis in Pregnancy with Intraocular Dissemination: A Case Report and Review of the Literature.

    PubMed

    Rezai, Shadi; LoBue, Stephen; Adams, Daniel; Oladipo, Yewande; Posso, Ramses; Mapp, Tiffany; Santiago, Crystal; Jain, Manisha; Marino, William D; Henderson, Cassandra E

    2015-01-01

    Background. Tuberculosis (TB) is a disease that affects hundreds of millions of people across the world. However, the incidence in developed countries has decreased over the past decades causing physicians to become unfamiliar with its unspecific symptoms. Pregnant individuals are especially difficult because many symptoms of active TB can mimic normal physiological changes of pregnancy. We present a case report of a 26-year-old multiparous woman, G4P3003, at 38-week gestation with a history of positive PPD who emigrated from Ghana 6 years ago. She came to the hospital with an initial complaint of suprapubic pain, pressure, and possible leakage of amniotic fluid for the past week. Patient also complained of a productive cough for the past 3 to 4 months with a decrease in vision occurring with the start of pregnancy. Visual acuity was worse than 20/200 in both eyes. Definitive diagnosis of active TB was delayed due to patient refusal of chest X-ray. Fortunately, delay in diagnosis was minimized since patient delivered within 24 hours of admission. Active TB was confirmed with intraocular dissemination. Patient had optic atrophy OS (left eye) and papillitis, choroiditis, and uveitis OD (right eye) due to TB infiltration. Fetus was asymptomatic and anti-TB therapy was started for both patients.

  19. Untreated Active Tuberculosis in Pregnancy with Intraocular Dissemination: A Case Report and Review of the Literature

    PubMed Central

    LoBue, Stephen; Adams, Daniel; Oladipo, Yewande; Posso, Ramses; Mapp, Tiffany; Santiago, Crystal; Jain, Manisha; Marino, William D.; Henderson, Cassandra E.

    2015-01-01

    Background. Tuberculosis (TB) is a disease that affects hundreds of millions of people across the world. However, the incidence in developed countries has decreased over the past decades causing physicians to become unfamiliar with its unspecific symptoms. Pregnant individuals are especially difficult because many symptoms of active TB can mimic normal physiological changes of pregnancy. We present a case report of a 26-year-old multiparous woman, G4P3003, at 38-week gestation with a history of positive PPD who emigrated from Ghana 6 years ago. She came to the hospital with an initial complaint of suprapubic pain, pressure, and possible leakage of amniotic fluid for the past week. Patient also complained of a productive cough for the past 3 to 4 months with a decrease in vision occurring with the start of pregnancy. Visual acuity was worse than 20/200 in both eyes. Definitive diagnosis of active TB was delayed due to patient refusal of chest X-ray. Fortunately, delay in diagnosis was minimized since patient delivered within 24 hours of admission. Active TB was confirmed with intraocular dissemination. Patient had optic atrophy OS (left eye) and papillitis, choroiditis, and uveitis OD (right eye) due to TB infiltration. Fetus was asymptomatic and anti-TB therapy was started for both patients. PMID:26693374

  20. IL23R(Arg381Gln) Functional Polymorphism Is Associated with Active Pulmonary Tuberculosis Severity

    PubMed Central

    Boukadida, Jalel

    2012-01-01

    The purpose of our study was to investigate the association between a functional single nucleotide polymorphism (SNP) in the interleukin-23 receptor gene (IL23R; rs11209026, 1142 Gwild type → Areduced function, Arg381Gln) and disease severity outcome in pulmonary tuberculosis (TB) in the Tunisian population. SNP was investigated in a population of 168 patients with active pulmonary TB (cases were stratified into patients with minimal/moderate lung involvement, i.e., patients with minimal/moderate disease [Pmd], and patients with extensive lung involvement, i.e., patients with active disease [Pad]) and 150 healthy subjects. Genotype analyses were carried out using the PCR-restriction fragment length polymorphism method. We have found that the IL23R reduced-function allele 1142A and genotypes AA and AG were overrepresented, especially in the Pad subgroup compared with the control group (51% versus 18% [P = 10−8], 33% versus 5% [P = 10−8], and 36% versus 26% [P = 5 × 10−3], respectively). Additionally, comparison of the Pad and the Pmd groups showed that the A allele and AA genotype seemed to be associated with 2.79-fold (P = 4 × 10−5) and 7.74-fold (P = 10−5) increased risks of TB with minimal/moderate lung involvement, respectively. Our results demonstrate that the reduced-function polymorphism 1142G → A encoded by IL23R influences the outcome of disease severity of active pulmonary TB in Tunisian patients. PMID:22695161

  1. Selective targeting of the conserved active site cysteine of Mycobacterium tuberculosis methionine aminopeptidase with electrophilic reagents.

    PubMed

    Reddi, Ravikumar; Arya, Tarun; Kishor, Chandan; Gumpena, Rajesh; Ganji, Roopa J; Bhukya, Supriya; Addlagatta, Anthony

    2014-09-01

    Methionine aminopeptidases (MetAPs) cleave initiator methionine from ~ 70% of the newly synthesized proteins in every living cell, and specific inhibition or knockdown of this function is detrimental. MetAPs are metalloenzymes, and are broadly classified into two subtypes, type I and type II. Bacteria contain only type I MetAPs, and the active site of these enzymes contains a conserved cysteine. By contrast, in type II enzymes the analogous position is occupied by a conserved glycine. Here, we report the reactivity of the active site cysteine in a type I MetAP, MetAP1c, of Mycobacterium tuberculosis (MtMetAP1c) towards highly selective cysteine-specific reagents. The authenticity of selective modification of Cys105 of MtMetAP1c was established by using site-directed mutagenesis and crystal structure determination of covalent and noncovalent complexes. On the basis of these observations, we propose that metal ions in the active site assist in the covalent modification of Cys105 by orienting the reagents appropriately for a successful reaction. These studies establish, for the first time, that the conserved cysteine of type I MetAPs can be targeted for selective inhibition, and we believe that this chemistry can be exploited for further drug discovery efforts regarding microbial MetAPs.

  2. Biochemical characterization of quinolinic acid phosphoribosyltransferase from Mycobacterium tuberculosis H37Rv and inhibition of its activity by pyrazinamide.

    PubMed

    Kim, Hyun; Shibayama, Keigo; Rimbara, Emiko; Mori, Shigetarou

    2014-01-01

    Quinolinic acid phosphoribosyltransferase (QAPRTase, EC 2.4.2.19) is a key enzyme in the de novo pathway of nicotinamide adenine dinucleotide (NAD) biosynthesis and a target for the development of new anti-tuberculosis drugs. QAPRTase catalyzes the synthesis of nicotinic acid mononucleotide from quinolinic acid (QA) and 5-phosphoribosyl-1-pyrophosphate (PRPP) through a phosphoribosyl transfer reaction followed by decarboxylation. The crystal structure of QAPRTase from Mycobacterium tuberculosis H37Rv (MtQAPRTase) has been determined; however, a detailed functional analysis of MtQAPRTase has not been published. Here, we analyzed the enzymatic activities of MtQAPRTase and determined the effect on catalysis of the anti-tuberculosis drug pyrazinamide (PZA). The optimum temperature and pH for MtQAPRTase activity were 60°C and pH 9.2. MtQAPRTase required bivalent metal ions and its activity was highest in the presence of Mg2+. Kinetic analyses revealed that the Km values for QA and PRPP were 0.08 and 0.39 mM, respectively, and the kcat values for QA and PRPP were 0.12 and 0.14 [s-1], respectively. When the amino acid residues of MtQAPRTase, which may interact with QA, were substituted with alanine residues, catalytic activity was undetectable. Further, PZA, which is an anti-tuberculosis drug and a structural analog of QA, markedly inhibited the catalytic activity of MtQAPRTase. The structure of PZA may provide the basis for the design of new inhibitors of MtQAPRTase. These findings provide new insights into the catalytic properties of MtQAPRTase.

  3. Design and synthesis of novel antimicrobials with activity against Gram-positive bacteria and mycobacterial species, including M. tuberculosis

    PubMed Central

    Tiruveedhula, V.V.N. Phani Babu; Witzigmann, Christopher M.; Verma, Ranjit; Kabir, M. Shahjahan; Rott, Marc; Schwan, William R.; Medina-Bielski, Sara; Lane, Michelle; Close, William; Polanowski, Rebecca L.; Sherman, David; Monte, Aaron; Deschamps, Jeffrey R.; Cook, James M.

    2013-01-01

    The alarming increase in bacterial resistance over the last decade along with a dramatic decrease in new treatments for infections has led to problems in the healthcare industry. Tuberculosis (TB) is caused mainly by Mycobacterium tuberculosis which is responsible for 1.4 million deaths per year. A world-wide threat with HIV co-infected with multi and extensively drug-resistant strains of TB has emerged. In this regard, herein, novel acrylic acid ethyl ester derivatives were synthesized in simple, efficient routes and evaluated as potential agents against several Mycobacterium species. These were synthesized via a stereospecific process for structure activity relationship (SAR) studies. Minimum inhibitory concentration (MIC) assays indicated that esters 12, 13, and 20 exhibited greater in vitro activity against Mycobacterium smegmatis than rifampin, one of the current, first-line anti-mycobacterial chemotherapeutic agents. Based on these studies the acrylic ester 20 has been developed as a potential lead compound which was found to have an MIC value of 0.4 μg/mL against Mycobacterium tuberculosis. The SAR and biological activity of this series is presented; a Michael – acceptor mechanism appears to be important for potent activity of this series of analogs. PMID:24200931

  4. Computational medicinal chemistry for rational drug design: Identification of novel chemical structures with potential anti-tuberculosis activity.

    PubMed

    Koseki, Yuji; Aoki, Shunsuke

    2014-01-01

    Tuberculosis (TB) is caused by the bacterium Mycobacterium tuberculosis and is a common infectious disease with high mortality and morbidity. The increasing prevalence of drug-resistant strains of TB presents a major public health problem. Due to the lack of effective drugs to treat these drug-resistant strains, the discovery or development of novel anti-TB drugs is important. Computer-aided drug design has become an established strategy for the identification of novel active chemicals through a combination of several drug design tools. In this review, we summarise the current chemotherapy for TB, describe attractive target proteins for the development of antibiotics against TB, and detail several computational drug design strategies that may contribute to the further identification of active chemicals for the treatment of not only TB but also other diseases.

  5. Granulocytic Myeloid Derived Suppressor Cells Expansion during Active Pulmonary Tuberculosis Is Associated with High Nitric Oxide Plasma Level

    PubMed Central

    El Daker, Sary; Sacchi, Alessandra; Tempestilli, Massimo; Carducci, Claudia; Goletti, Delia; Vanini, Valentina; Colizzi, Vittorio; Lauria, Francesco Nicola; Martini, Federico; Martino, Angelo

    2015-01-01

    Tuberculosis (TB) is still the principal cause of death caused by a single infectious agent, and the balance between the bacillus and host defense mechanisms reflects the different manifestations of the pathology. The aim of this work was to study the role of myeloid-derived suppressor cells (MDSCs) during active pulmonary tuberculosis at the site of infection. We observed an expansion of MDSCs in the lung and blood of patients with active TB, which are correlated with an enhanced amount of nitric oxide in the plasma. We also found that these cells have the remarkable ability to suppress T-cell response, suggesting an important role in the modulation of the immune response against TB. Interestingly, a trend in the diminution of MDSCs was found after an efficacious anti-TB therapy, suggesting that these cells may be used as a potential biomarker for monitoring anti-TB therapy efficacy. PMID:25879532

  6. 2-(Quinolin-4-yloxy)acetamides Are Active against Drug-Susceptible and Drug-Resistant Mycobacterium tuberculosis Strains

    PubMed Central

    2016-01-01

    2-(Quinolin-4-yloxy)acetamides have been described as potent in vitro inhibitors of Mycobacterium tuberculosis growth. Herein, additional chemical modifications of lead compounds were carried out, yielding highly potent antitubercular agents with minimum inhibitory concentration (MIC) values as low as 0.05 μM. Further, the synthesized compounds were active against drug-resistant strains and were devoid of apparent toxicity to Vero and HaCat cells (IC50s ≥ 20 μM). In addition, the 2-(quinolin-4-yloxy)acetamides showed intracellular activity against the bacilli in infected macrophages with action similar to rifampin, low risk of drug–drug interactions, and no sign of cardiac toxicity in zebrafish (Danio rerio) at 1 and 5 μM. Therefore, these data indicate that this class of compounds may furnish candidates for future development to, hopefully, provide drug alternatives for tuberculosis treatment. PMID:26985307

  7. The three Mycobacterium tuberculosis antigen 85 isoforms have unique substrates and activities determined by non-active site regions.

    PubMed

    Backus, Keriann M; Dolan, Michael A; Barry, Conor S; Joe, Maju; McPhie, Peter; Boshoff, Helena I M; Lowary, Todd L; Davis, Benjamin G; Barry, Clifton E

    2014-09-05

    The three isoforms of antigen 85 (A, B, and C) are the most abundant secreted mycobacterial proteins and catalyze transesterification reactions that synthesize mycolated arabinogalactan, trehalose monomycolate (TMM), and trehalose dimycolate (TDM), important constituents of the outermost layer of the cellular envelope of Mycobacterium tuberculosis. These three enzymes are nearly identical at the active site and have therefore been postulated to exist to evade host immunity. Distal to the active site is a second putative carbohydrate-binding site of lower homology. Mutagenesis of the three isoforms at this second site affected both substrate selectivity and overall catalytic activity in vitro. Using synthetic and natural substrates, we show that these three enzymes exhibit unique selectivity; antigen 85A more efficiently mycolates TMM to form TDM, whereas C (and to a lesser extent B) has a higher rate of activity using free trehalose to form TMM. This difference in substrate selectivity extends to the hexasaccharide fragment of cell wall arabinan. Mutation of secondary site residues from the most active isoform (C) into those present in A or B partially interconverts this substrate selectivity. These experiments in combination with molecular dynamics simulations reveal that differences in the N-terminal helix α9, the adjacent Pro(216)-Phe(228) loop, and helix α5 are the likely cause of changes in activity and substrate selectivity. These differences explain the existence of three isoforms and will allow for future work in developing inhibitors.

  8. Antigen-Specific IFN-γ Responses Correlate with the Activity of M. tuberculosis Infection but Are Not Associated with the Severity of Tuberculosis Disease

    PubMed Central

    Nikitina, Irina Yu.; Panteleev, Alexander V.; Karpina, Natalya L.; Bagdasarian, Tatef R.; Burmistrova, Irina A.; Andreevskaya, Sofia N.; Chernousova, Larisa N.; Vasilyeva, Irina A.

    2016-01-01

    IFN-γ is a key cytokine in antituberculosis (TB) defense. However, how the levels of its secretion affect M. tuberculosis (Mtb) infection is not clear. We have analyzed associations between IFN-γ responses measured in QuantiFERON®-TB Gold In-tube (QFT) assay, TB disease severity, and Mtb infection activity. TB severity was evaluated based on the results of radiological, microbiological, and clinical examinations. Antigen-driven IFN-γ secretion did not correlate with TB severity. Mitogen-induced IFN-γ secretion correlated inversely with the form of pulmonary pathology and the area of affected pulmonary tissue; the levels of spontaneous IFN-γ secretion correlated with patients' age (r = 0.395, p = 0.001). Mtb infection activity was evaluated based on radiological data of lung tissue infiltration, destruction, dissemination or calcification, and condensation. The rate of positive QFT results and the levels of antigen-driven IFN-γ secretion increased in a row: patients with residual TB lesions < patients with low TB activity < patients with high TB activity. Thus, antigen-driven IFN-γ secretion and QFT results did not associate with TB severity but associated with the infection activity. The results suggest that quantitative parameters of IFN-γ secretion play a minor role in determining the course of TB disease but mirror the activity of the infectious process. PMID:28042583

  9. Antigen-Specific IFN-γ Responses Correlate with the Activity of M. tuberculosis Infection but Are Not Associated with the Severity of Tuberculosis Disease.

    PubMed

    Nikitina, Irina Yu; Panteleev, Alexander V; Sosunova, Ekaterina V; Karpina, Natalya L; Bagdasarian, Tatef R; Burmistrova, Irina A; Andreevskaya, Sofia N; Chernousova, Larisa N; Vasilyeva, Irina A; Lyadova, Irina V

    2016-01-01

    IFN-γ is a key cytokine in antituberculosis (TB) defense. However, how the levels of its secretion affect M. tuberculosis (Mtb) infection is not clear. We have analyzed associations between IFN-γ responses measured in QuantiFERON®-TB Gold In-tube (QFT) assay, TB disease severity, and Mtb infection activity. TB severity was evaluated based on the results of radiological, microbiological, and clinical examinations. Antigen-driven IFN-γ secretion did not correlate with TB severity. Mitogen-induced IFN-γ secretion correlated inversely with the form of pulmonary pathology and the area of affected pulmonary tissue; the levels of spontaneous IFN-γ secretion correlated with patients' age (r = 0.395, p = 0.001). Mtb infection activity was evaluated based on radiological data of lung tissue infiltration, destruction, dissemination or calcification, and condensation. The rate of positive QFT results and the levels of antigen-driven IFN-γ secretion increased in a row: patients with residual TB lesions < patients with low TB activity < patients with high TB activity. Thus, antigen-driven IFN-γ secretion and QFT results did not associate with TB severity but associated with the infection activity. The results suggest that quantitative parameters of IFN-γ secretion play a minor role in determining the course of TB disease but mirror the activity of the infectious process.

  10. [Head and neck tuberculosis: a still urgent problem].

    PubMed

    Bruzgielewicz, A; Wysocki, J; Osuch-Wójcikiewicz, E

    1995-01-01

    The upper respiratory tract is an unusual site for tuberculous infection. Most of the cases are secondary to active pulmonary tuberculosis. We present thirty five cases of tuberculosis localize in the head and neck region. There were twelve patients with lymphonodular tuberculosis, eleven patients with laryngeal tuberculosis, six patients with oral and pharyngeal tuberculosis, three patients with partoid gland tuberculosis, two patients with nose and paranasal sinuses tuberculosis and one patient with middle ear tuberculosis. This cases exemplifies the difficulty in diagnosis of tuberculosis in such an unusual sites.

  11. Anti-Mycobacterium tuberculosis Activity of Calophyllum brasiliense Extracts Obtained by Supercritical Fluid Extraction and Conventional Techniques.

    PubMed

    Pires, Claudia T A; de L Scodro, Regiane B; Brenzan, Mislaine A; Cortez, Diógenes A G; Siqueira, Vera L D; Cardozo-Filho, Lúcio; Goncalves, Renata M; Caleffi-Ferracioli, Katiany R; Cardoso, Rosilene F

    2016-01-01

    The conventional techniques used to extract natural products have many disadvantages, and alternative methods have been used, such as supercritical fluid extraction (SFE-CO2). We compared the anti-Mycobacterium tuberculosis activity and cytotoxicity of extracts and major pure compounds were obtained from the leaves of Calophyllum brasiliense by SFE-CO2, maceration and Soxhlet. Anti-M tuberculosis activity was evaluated by resazurin microtiter assay plate and cytotoxicity assay was performed using 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide. The (-) mammea A/BB, (-) mammea B/BB, mammea B/BB cyclo D, ponnalide, mammea A/BA cyclo D, and amentoflavone were identified as the majority compounds. SFE-CO2, especially at 313 K and 10.92 MPa showed better yield for (-) mammea A/BB. Anti-M. tuberculosis activity (62.5 μg/mL) and cytotoxicity (Selectivity Index = 0.320-0.576) were similar for the three extracts. Mammea B/BB cyclo D had a minimum inhibitory concentration (MIC) of 125 μg/mL, and ponnalide and mammea A/BA cyclo D had MICs > 250 μg/mL. The pure compounds isolated showed low Selectivity Index (< 0.09). SFE-CO2 may be more promising than conventional methods for the extraction of compound (-) mammea A/BB, which presented the best anti-M. tuberculosis activity in our previous study. This is important for current industrial requirements to obtain extracts from medicinal plants using clean technologies.

  12. Immunochromatographic IgG/IgM test for rapid diagnosis of active tuberculosis.

    PubMed

    Ben-Selma, Walid; Harizi, Hedi; Boukadida, Jalel

    2011-12-01

    For rapid diagnosis and discrimination between active tuberculosis (TB) and other pulmonary diseases, we evaluated the clinical usefulness of detection of serum immunoglobulin IgG and IgM antibodies raised against mycobacterial 38-kDa, 16-kDa, and 6-kDa antigens by a commercial rapid immunochromatographic IgG/IgM test (Standard Diagnostics, South Korea) in 246 serum samples from three groups of patients: (i) 171 patients with active TB (128 with pulmonary TB [pTB] and 43 with extrapulmonary TB [epTB]), (ii) 73 patients with pulmonary non-TB diseases, and (iii) two leprosy patients. The sensitivities of IgG and IgM in patients with active TB (pTB and epTB) were 68.4% and 2.3%, respectively. IgG had the best performance characteristics, with sensitivities of 78.1% and 39.5% in sera from patients with active pTB and epTB, respectively, and a specificity of 100%. The sensitivities of IgM were poor and were similar for pTB and epTB (2.3%). In contrast, specificity was very elevated (100%). The combination of IgG with IgM did not improve its sensitivity. IgG-mediated responses against the mycobacterial 38-kDa, 16-kDa, and 6-kDa antigens might constitute a clinically useful tool for presumptive diagnosis and discrimination of active pTB from other pulmonary diseases. Moreover, based on its simplicity and rapidity of application, it could be a screening tool for active pTB in poorly equipped laboratories.

  13. Tuberculosis trends in the U.S. Armed Forces, active component, 1998-2012.

    PubMed

    Mancuso, James D; Aaron, Christopher L

    2013-05-01

    Members of the Armed Forces represent a segment of the U.S. population that may be at increased risk for tuberculosis (TB) infection, disease, and transmission due to overseas service in endemic areas and residence in congregate settings. The purpose of this study was to examine recent surveillance trends and risk factors associated with TB disease in the active component U.S. military. The rate of TB in the U.S. military -0.6 per 100,000 population (n=128) over the interval from 1998 to 2012 - was lower than the age-adjusted rate among the U.S. population (adjusted rate ratio=0.20) over the same time interval. During the last five years of the surveillance period, the most common factor associated with the diagnosis of TB disease during military service was latent infection at time of accession; also, as many as nine (24%) cases of TB were associated with deployment to Iraq or other military exposures. TB control activities should continue to mitigate unique military exposures such as crowding during recruit training and deployments to TB endemic areas.

  14. Tuberculosis screening and compliance with return for skin test reading among active drug users.

    PubMed Central

    Malotte, C K; Rhodes, F; Mais, K E

    1998-01-01

    OBJECTIVES: This study assessed the independent and combined effects of different levels of monetary incentives and a theory-based educational intervention on return for tuberculosis (TB) skin test reading in a sample of active injection drug and crack cocaine users. Prevalence of TB infection in this sample was also determined. METHODS: Active or recent drug users (n = 1004), recruited via street outreach techniques, were skin tested for TB. They were randomly assigned to 1 of 2 levels of monetary incentive ($5 and $10) provided at return for skin test reading, alone or in combination with a brief motivational education session. RESULTS: More than 90% of those who received $10 returned for skin test reading, in comparison with 85% of those who received $5 and 33% of those who received no monetary incentive. The education session had no impact on return for skin test reading. The prevalence of a positive tuberculin test was 18.3%. CONCLUSIONS: Monetary incentives dramatically increase the return rate for TB skin test reading among drug users who are at high risk of TB infection. PMID:9585747

  15. Active Tuberculosis Case Finding Interventions Among Immigrants, Refugees and Asylum Seekers in Italy

    PubMed Central

    Schepisi, Monica Sañé; Gualano, Gina; Piselli, Pierluca; Mazza, Marta; D’Angelo, Donatella; Fasciani, Francesca; Barbieri, Alberto; Rocca, Giorgia; Gnolfo, Filippo; Olivani, Piefranco; Ferrarese, Maurizio; Codecasa, Luigi Ruffo; Palmieri, Fabrizio; Girardi, Enrico

    2016-01-01

    In Italy tuberculosis (TB) is largely concentrated in vulnerable groups such as migrants and in urban settings. We analyzed three TB case finding interventions conducted at primary centers and mobile clinics for regular/irregular immigrants and refugees/asylum seekers performed over a four-year period (November 2009-March 2014) at five different sites in Rome and one site in Milan, Italy. TB history and presence of symptoms suggestive of active TB were investigated by verbal screening through a structured questionnaire in migrants presenting for any medical condition to out-patient and mobile clinics. Individuals reporting TB history or symptoms were referred to a TB clinic for diagnostic workup. Among 6347 migrants enrolled, 891 (14.0%) reported TB history or symptoms suggestive of active TB and 546 (61.3%) were referred to the TB clinic. Of them, 254 (46.5%) did not present for diagnostic evaluation. TB was diagnosed in 11 individuals representing 0.17% of those screened and 3.76% of those evaluated. The overall yield of this intervention was in the range reported for other TB screening programs for migrants, although we recorded an unsatisfactory adherence to diagnostic workup. Possible advantages of this intervention include low cost and reduced burden of medical procedures for the screened population. PMID:27403270

  16. Target-based identification of whole-cell active inhibitors of biotin biosynthesis in Mycobacterium tuberculosis.

    PubMed

    Park, Sae Woong; Casalena, Dominick E; Wilson, Daniel J; Dai, Ran; Nag, Partha P; Liu, Feng; Boyce, Jim P; Bittker, Joshua A; Schreiber, Stuart L; Finzel, Barry C; Schnappinger, Dirk; Aldrich, Courtney C

    2015-01-22

    Biotin biosynthesis is essential for survival and persistence of Mycobacterium tuberculosis (Mtb) in vivo. The aminotransferase BioA, which catalyzes the antepenultimate step in the biotin pathway, has been established as a promising target due to its vulnerability to chemical inhibition. We performed high-throughput screening (HTS) employing a fluorescence displacement assay and identified a diverse set of potent inhibitors including many diversity-oriented synthesis (DOS) scaffolds. To efficiently select only hits targeting biotin biosynthesis, we then deployed a whole-cell counterscreen in biotin-free and biotin-containing medium against wild-type Mtb and in parallel with isogenic bioA Mtb strains that possess differential levels of BioA expression. This counterscreen proved crucial to filter out compounds whose whole-cell activity was off target as well as identify hits with weak, but measurable whole-cell activity in BioA-depleted strains. Several of the most promising hits were cocrystallized with BioA to provide a framework for future structure-based drug design efforts.

  17. UvrD2 is essential in Mycobacterium tuberculosis, but its helicase activity is not required.

    PubMed

    Williams, Alan; Güthlein, Carolin; Beresford, Nicola; Böttger, Erik C; Springer, Burkhard; Davis, Elaine O

    2011-09-01

    UvrD is an SF1 family helicase involved in DNA repair that is widely conserved in bacteria. Mycobacterium tuberculosis has two annotated UvrD homologues; here we investigate the role of UvrD2. The uvrD2 gene at its native locus could be knocked out only in the presence of a second copy of the gene, demonstrating that uvrD2 is essential. Analysis of the putative protein domain structure of UvrD2 shows a distinctive domain architecture, with an extended C terminus containing an HRDC domain normally found in SF2 family helicases and a linking domain carrying a tetracysteine motif. Truncated constructs lacking the C-terminal domains of UvrD2 were able to compensate for the loss of the chromosomal copy, showing that these C-terminal domains are not essential. Although UvrD2 is a functional helicase, a mutant form of the protein lacking helicase activity was able to permit deletion of uvrD2 at its native locus. However, a mutant protein unable to hydrolyze ATP or translocate along DNA was not able to compensate for lack of the wild-type protein. Therefore, we concluded that the essential role played by UvrD2 is unlikely to involve its DNA unwinding activity and is more likely to involve DNA translocation and, possibly, protein displacement.

  18. Tomographic Aspects of Advanced Active Pulmonary Tuberculosis and Evaluation of Sequelae following Treatment

    PubMed Central

    Capone, Domenico; Mafort, Thiago; Mogami, Roberto; Rodrigues, Rosana de Souza; Menna Barreto, Miriam

    2017-01-01

    Objectives. To evaluate tomographic changes in pulmonary tuberculosis (TB), degree of agreement among three radiologists regarding tomographic diagnoses, and sequelae following treatment. Methods. Cross-sectional and descriptive study of 74 TB patients confirmed by sputum culture and chest computed tomography before (CT1) and 6 months after (CT2) drug therapy. Results were performed by three radiologists blinded to clinical and laboratory results. Results. Main findings in CT1 included nodules indicating the presence of a tree-in-bud pattern in 93% of cases, ill-defined nodules in 84% of cases, consolidation in 77% of cases, architectural distortion in 71% of cases, cavitary lesions in 62% of cases, and ground glass opacities in 37% of cases. Airway involvement, characterized by increased thickness and dilatation of the bronchial walls, occurred in 93% of cases. Pleural involvement occurred in 54%. There was an agreement on active TB among the three radiologists in 85% of cases. The results in CT2 indicated the presence of architectural distortion in 91% of cases and cylindrical bronchiectasis in 86%. Conclusions. The study established a tomographic pattern for diagnosis of active TB characterized by the presence of airway nodules, consolidation, architectural distortion, and cavitary lesions, and an almost complete degree of agreement (Kappa) was observed among the radiologists (0.85). CT after treatment assists in defining the cure. PMID:28261498

  19. Increased mortality associated with treated active tuberculosis in HIV-infected adults in Tanzania.

    PubMed

    Kabali, Conrad; Mtei, Lillian; Brooks, Daniel R; Waddell, Richard; Bakari, Muhammad; Matee, Mecky; Arbeit, Robert D; Pallangyo, Kisali; von Reyn, C Fordham; Horsburgh, C Robert

    2013-07-01

    Active tuberculosis (TB) among HIV-infected patients, even when successfully treated, may be associated with excess mortality. We conducted a prospective cohort study nested in a randomized TB vaccine trial to compare mortality between HIV-infected patients diagnosed and treated for TB (TB, n = 77) and HIV-infected patients within the same CD4 range, who were not diagnosed with or treated for active TB (non-TB, n = 308) in the period 2001-2008. Only twenty four subjects (6%) were on antiretroviral therapy at the beginning of this study. After accounting for covariate effects including use of antiretroviral therapy, isoniazid preventive therapy, and receipt of vaccine, we found a four-fold increase in mortality in TB patients compared with non-TB patients (adjusted Hazard Ratio 4.61; 95% Confidence Interval (CI): 1.63, 13.05). These findings suggest that treatment for TB alone is not sufficient to avert the excess mortality associated with HIV-related TB and that prevention of TB may provide a mortality benefit.

  20. Active tuberculosis among homeless persons, Toronto, Ontario, Canada, 1998-2007.

    PubMed

    Khan, Kamran; Rea, Elizabeth; McDermaid, Cameron; Stuart, Rebecca; Chambers, Catharine; Wang, Jun; Chan, Angie; Gardam, Michael; Jamieson, Frances; Yang, Jae; Hwang, Stephen W

    2011-03-01

    While tuberculosis (TB) in Canadian cities is increasingly affecting foreign-born persons, homeless persons remain at high risk. To assess trends in TB, we studied all homeless persons in Toronto who had a diagnosis of active TB during 1998-2007. We compared Canada-born and foreign-born homeless persons and assessed changes over time. We identified 91 homeless persons with active TB; they typically had highly contagious, advanced disease, and 19% died within 12 months of diagnosis. The proportion of homeless persons who were foreign-born increased from 24% in 1998-2002 to 39% in 2003-2007. Among foreign-born homeless persons with TB, 56% of infections were caused by strains not known to circulate among homeless persons in Toronto. Only 2% of infections were resistant to first-line TB medications. The rise in foreign-born homeless persons with TB strains likely acquired overseas suggests that the risk for drug-resistant strains entering the homeless shelter system may be escalating.

  1. Target-Based Identification of Whole-Cell Active Inhibitors of Biotin Biosynthesis in Mycobacterium tuberculosis

    PubMed Central

    Park, Sae Woong; Casalena, Dominick; Wilson, Daniel; Dai, Ran; Nag, Partha; Liu, Feng; Boyce, Jim P.; Bittker, Joshua; Schreiber, Stuart; Finzel, Barry C.; Schnappinger, Dirk; Aldrich, Courtney C.

    2014-01-01

    SUMMARY Biotin biosynthesis is essential for survival and persistence of Mycobacterium tuberculosis (Mtb) in vivo. The aminotransferase BioA, which catalyzes the antepenultimate step in the biotin pathway, has been established as a promising target due to its vulnerability to chemical inhibition. We performed high-throughput screening (HTS) employing a fluorescence displacement assay and identified a diverse set of potent inhibitors including many diversity-oriented synthesis (DOS) scaffolds. To efficiently select only hits targeting biotin biosynthesis, we then deployed a whole-cell counter-screen in either biotin-free and biotin-containing medium against wild-type Mtb and in parallel with isogenic bioA Mtb strains that possess differential levels of BioA expression. This counter-screen proved crucial to filter out compounds whose whole-cell activity was off-target as well as identify hits with weak, but measurable whole-cell activity in BioA-depleted strains. Several of the most promising hits were co-crystallized with BioA to provide a framework for future structure-based drug design efforts. PMID:25556942

  2. Comparison of symptoms and treatment outcomes between actively and passively detected tuberculosis cases: the additional value of active case finding.

    PubMed

    den Boon, S; Verver, S; Lombard, C J; Bateman, E D; Irusen, E M; Enarson, D A; Borgdorff, M W; Beyers, N

    2008-10-01

    Passive detection of tuberculosis (TB) cases may lead to delay in treatment which may contribute to increased severity of disease and mortality. Active case finding may be an alternative. In a community survey in Cape Town, South Africa, we actively detected 27 bacteriologically positive TB cases and compared those with 473 passively detected TB cases. Seven of 27 (26%) actively detected TB cases did not start treatment within 2 months and were considered initial defaulters. Those who did start treatment had similar treatment success rates as passively detected TB cases (both 80%) (OR 1.01, CI 0.33-3.09). Passively detected cases reported the presence of the symptoms cough (OR 3.72, 95% CI 1.47-9.39), haemoptysis (OR 3.20, 95% CI 1.03-9.93), night sweats (OR 3.35, 95% CI 1.40-7.99), fever (OR 4.28, 95% CI 1.21-15.14), and weight loss (OR 11.14, 95% CI 4.17-29.74) more often than those detected actively. We conclude that although TB cases detected by a community survey are less symptomatic and are prone to a high initial default rate, active case finding can potentially identify a substantial portion of the existing caseload at an earlier stage of disease, thereby reducing the risk of transmission.

  3. Structure-activity relationship of new anti-tuberculosis agents derived from oxazoline and oxazole benzyl esters.

    PubMed

    Moraski, Garrett C; Chang, Mayland; Villegas-Estrada, Adriel; Franzblau, Scott G; Möllmann, Ute; Miller, Marvin J

    2010-05-01

    During the syntheses and studies of natural iron chelators (mycobactins), we serendipitously discovered that a simple, small molecule, oxazoline-containing intermediate 3 displayed surprising anti-tuberculosis activity (MIC of 7.7 microM, average). Herein we report elaboration of SAR around this hit as well as the syntheses and evaluation of a hundred oxazoline- and oxazole-containing compounds derived from an efficient three step process: 1) formation of beta-hydroxy amides with serine or threonine; 2) cyclization to afford oxazolines; and 3) dehydration to give the corresponding oxazoles. A number of compounds prepared by this method were shown to possess impressive activity against Mycobacterium tuberculosis, extremely low toxicity and therefore high therapeutic indexes, as well as activity against even the more recalcitrant non-replicating form of M. tuberculosis. The uniqueness of their structures and their simplicity should allow them to be further optimized to meet ADME (absorption, distribution, metabolism, excretion) requirements. The syntheses of eight of the most potent in vitro compounds were scaled up and the compounds were tested in an in vivo mouse infection model to evaluate their efficacy before engaging upon more elaborate compound design and optimization.

  4. Bacterial expression and antibiotic activities of recombinant variants of human β-defensins on pathogenic bacteria and M. tuberculosis.

    PubMed

    Corrales-Garcia, Ligia; Ortiz, Ernesto; Castañeda-Delgado, Julio; Rivas-Santiago, Bruno; Corzo, Gerardo

    2013-05-01

    Five variants of human β-defensins (HBDs) were expressed in Escherichia coli using two vector systems (pET28a(+) and pQE30) with inducible expression by IPTG. The last vector has not been previously reported as an expression system for HBDs. The recombinant peptides were different in their lengths and overall charge. The HBDs were expressed as soluble or insoluble proteins depending on the expression system used, and the final protein yields ranged from 0.5 to 1.6 mg of peptide/g of wet weight cells, with purities higher than 90%. The recombinant HBDs demonstrated a direct correlation between antimicrobial activity and the number of basic charged residues; that is, their antimicrobial activity was as follows: HBD3-M-HBD2 > HBD3 = HBD3-M = HB2-KLK > HBD2 when assayed against E. coli, Staphylococcus aureus and Pseudomonas aeruginosa. Interestingly, HBD2 had the best antimicrobial activity against the Mycobacterium tuberculosis strain H37Rv (1.5 μM) and the heterologous tandem peptide, HBD3-M-HBD2, had the best minimal inhibitory concentration (MIC) value (2.7 μM) against a multidrug resistance strain (MDR) of M. tuberculosis, demonstrating the feasibility of the use of HBDs against pathogenic M. tuberculosis reported to be resistant to commercial antibiotics.

  5. [Tuberculosis in Switzerland].

    PubMed

    Shang, H; Desgrandchamps, D

    1995-10-03

    In Switzerland, in 1992, 957 persons suffered from tuberculosis; 52.3% were Swiss, 47.7% foreigners. Most of the swiss TB patients were more than 65 years old, whereas the foreigners generally were young patients originating from countries with high TB-infection rates. Asylum seekers had much higher TB-case rates (131 cases per 100,000) than other foreigners (27 cases per 100,000) or Swiss (9 cases per 100,000). Special refuge reception centers have been set up in Switzerland, in charge of tuberculosis screening procedures in this high-risk group on arrival to this country. Although HIV and AIDS patients bear a much higher risk of developing tuberculosis once infected, the HIV epidemic did not lead to an increase of tuberculosis in Switzerland so far, since young Swiss are rarely infected with tuberculosis. HIV-infected, drug addicts, homeless persons and alcoholics run a higher risk of contracting tuberculosis only when congregating with a person suffering from active tuberculosis not yet diagnosed or improperly treated. In order to maintain low levels of tuberculosis in Switzerland DOT (directly observed therapy) must be implemented in all patients with uncertain compliance, especially as cultural and social backgrounds become increasingly complex.

  6. Modulation of the Activity of Mycobacterium tuberculosis LipY by Its PE Domain

    PubMed Central

    Garrett, Christopher K.; Broadwell, Lindsey J.; Hayne, Cassandra K.; Neher, Saskia B.

    2015-01-01

    Mycobacterium tuberculosis harbors over 160 genes encoding PE/PPE proteins, several of which have roles in the pathogen’s virulence. A number of PE/PPE proteins are secreted via Type VII secretion systems known as the ESX secretion systems. One PE protein, LipY, has a triglyceride lipase domain in addition to its PE domain. LipY can regulate intracellular triglyceride levels and is also exported to the cell wall by one of the ESX family members, ESX-5. Upon export, LipY’s PE domain is removed by proteolytic cleavage. Studies using cells and crude extracts suggest that LipY’s PE domain not only directs its secretion by ESX-5, but also functions to inhibit its enzymatic activity. Here, we attempt to further elucidate the role of LipY’s PE domain in the regulation of its enzymatic activity. First, we established an improved purification method for several LipY variants using detergent micelles. We then used enzymatic assays to confirm that the PE domain down-regulates LipY activity. The PE domain must be attached to LipY in order to effectively inhibit it. Finally, we determined that full length LipY and the mature lipase lacking the PE domain (LipYΔPE) have similar melting temperatures. Based on our improved purification strategy and activity-based approach, we concluded that LipY’s PE domain down-regulates its enzymatic activity but does not impact the thermal stability of the enzyme. PMID:26270534

  7. Peer-led active tuberculosis case-finding among people living with HIV: lessons from Nepal

    PubMed Central

    Joshi, Dipu; Sthapit, Raisha

    2017-01-01

    Abstract Problem People living with a human immunodeficiency virus (HIV) infection have a high risk of tuberculosis and should undergo regular screening. However, they can be difficult to reach because they are stigmatized and discriminated against. Approach In Nepal, the nongovernmental organization Naya Goreto implemented a peer-led tuberculosis screening project in which people living with HIV volunteered to contact others in this high-risk population. Volunteers took part in a short training course, after which they attempted to contact people living with HIV through existing networks and self-help groups. Tuberculosis screening and testing were carried out in accordance with national guidelines. Local setting In Nepal, the prevalence of HIV infection is 0.3% in the general population but is much higher, at 6%, in people in Kathmandu who inject drugs. To date, the health system has not been able to implement systematic tuberculosis screening in people living with HIV. Relevant changes Between May 2014 and mid-September 2015, 30 volunteers screened 6642 people in 10 districts, 5430 (82%) of whom were living with HIV. Of the 6642, 6046 (91%) were tested for tuberculosis and 287 (4.3%) were diagnosed with the disease, 240 of whom were HIV-positive. Of those with tuberculosis, 270 (94%) initiated treatment. Lessons learnt Using peers to contact people living with HIV for tuberculosis screening resulted in a high participation rate and the identification of a considerable number of HIV-positive tuberculosis patients. Follow-up during treatment was difficult in this highly mobile group and needs more attention in future interventions. PMID:28250514

  8. [Frequency of previous tuberculosis history in patients with and without active tuberculosis admitted to our hospital in 1980-83 and in 1997-99].

    PubMed

    Nagayama, Naohiro; Baba, Motoo; Hori, Akihiro; Tamura, Atsuhisa; Nagai, Hideaki; Akagawa, Shinobu; Kawabe, Yoshiko; Machida, Kazuko; Kurashima, Atsuyuki; Yotsumoto, Hideki; Mouri, Masashi

    2002-07-01

    To study recurrence rate over a long period after recovery from previous tuberculosis history, we examined the frequency of previous tuberculosis history in patients who were admitted to our hospital in 1980-83 and in 1997-99 and the comparison was made between cases with and without culture-positive tuberculosis. The tuberculosis groups comprised of 297 patients in 1980-83 and 688 patients in 1997-99. The non-tuberculosis groups (control groups) comprised of 373 patients in 1980-83 and 1092 patients in 1997-99 with non-tuberculosis diseases other than the tuberculosis-related diseases such as non-tuberculosis mycobacteriosis, pulmonary aspergillosis, bronchiectasis, chronic bronchitis and tuberculosis sequelae. The patients with viral chronic hepatitis previously operated and transfused were also excluded as they might be operated because of pulmonary tuberculosis in the era of surgical treatment for tuberculosis. In both tuberculosis and control groups, they had previous tuberculosis history most frequently when they were twenties. In the control groups, the frequency of previous tuberculosis history among cases admitted in 1980-83 and were born in 1910-19, 20-29, 30-39, 40-49 were 15/84 (17.9%), 22/93 (23.7%), 11/77 (14.3%) and 3/43 (7.0%), respectively, and those admitted in 1997-99 were 11/70 (15.7%), 30/231 (13.0%), 28/288 (9.7%), and 10/230 (4.3%), respectively. In these 4 birth year groups, frequency of previous tuberculosis history among cases admitted in 1997-99 were significantly lower than that admitted in 1980-83 (p < 0.05, one-sided paired t-test), and the fact suggests that persons with tuberculosis history died earlier than those without it. In the tuberculosis groups, the frequencies of previous tuberculosis history among cases admitted in 1980-83 and were born in 1910-19, 20-29, 30-39 and 40-49 were 20/35 (57.1%), 31/58 (53.4%), 19/48 (39.6%), and 11/53 (20.8%), respectively, and those among cases admitted in 1997-99 were 30/99 (30.3%), 58/125 (46

  9. Cutaneous Tuberculosis

    PubMed Central

    Frankel, Amylynne; Penrose, Carolin

    2009-01-01

    Cutaneous tuberculosis occurs rarely, despite a high and increasing prevalence of tuberculosis worldwide. Mycobacterium tuberculosis, Mycobacterrium bovis, and the Bacille Calmette-Guérin vaccine can cause tuberculosis involving the skin. Cutaneous tuberculosis can be acquired exogenously or endogenously and present as a multitude of differing clinical morphologies. Diagnosis of these lesions can be difficult, as they resemble many other dermatological conditions that are often primarily considered. Further, microbiological confirmation is poor, despite scientific advances, such as the more frequent use of polymerase chain reaction. The authors report a case that illustrates the challenges faced by dermatologists when considering a diagnosis of cutaneous tuberculosis. PMID:20725570

  10. Mycobacterium tuberculosis Promotes Anti-apoptotic Activity of the Macrophage by PtpA Protein-dependent Dephosphorylation of Host GSK3α*

    PubMed Central

    Poirier, Valérie; Bach, Horacio; Av-Gay, Yossef

    2014-01-01

    Mycobacterium tuberculosis tyrosine phosphatase PtpA inhibits two key cellular events in macrophages required for the elimination of invading organisms, phagosome acidification, and maturation. Kinome analysis revealed multiple PtpA-dependent changes to the phosphorylation status of macrophage proteins upon M. tuberculosis infection. Among those proteins we show that PtpA dephosphorylates GSK3α on amino acid Tyr279, which leads to modulation of GSK3α anti-apoptotic activity, promoting pathogen survival early during infection. PMID:25187516

  11. New nitrofurans amenable by isocyanide multicomponent chemistry are active against multidrug-resistant and poly-resistant Mycobacterium tuberculosis.

    PubMed

    Krasavin, Mikhail; Parchinsky, Vladislav; Kantin, Grigory; Manicheva, Olga; Dogonadze, Marine; Vinogradova, Tatiana; Karge, Bianka; Brönstrup, Mark

    2017-03-15

    A set of structurally diverse N-amino δ-lactams decorated with a 5-nitro-2-furyl moiety was synthesized using isocyanide-based multicomponent chemistry and evaluated for antibacterial activity. Three compounds displayed a selective and potent (MIC 22-33μM) inhibition of M. tuberculosis H37Rv strain growth, while other Gram-positive (MRSA and E. faecium) or Gram-negative (E. coli, P. aeruginosa, A. baumannii, K. pneumoniae) pathogens were not affected. The compounds also displayed moderate-low cytotoxicity, as demonstrated in cell line viability assays. Several multidrug- and poly-resistant patient-derived M. tuberculosis strains were found to be susceptible to treatment with these compounds. The three most potent compounds share a significant structural similarity which provides a basis for further scaffold-hopping analog design.

  12. Bacteriostatic and bactericidal activities of benzoxazinorifamycin KRM-1648 against Mycobacterium tuberculosis and Mycobacterium avium in human macrophages.

    PubMed Central

    Mor, N; Simon, B; Heifets, L

    1996-01-01

    Inhibitory and bactericidal activities of KRM-1648 were determined against Mycobacterium tuberculosis and M. avium residing in human monocyte-derived macrophages and extracellular M. tuberculosis and M. avium. MICs and MBCs of KRM-1648 against intracellular and extracellular bacteria were substantially lower than those of rifampin. The MICs and MBCs of either drug against the intracellular bacteria were only twofold lower than or equal to the values found for extracellular bacteria. The prolonged effect of KRM-1648 found in this study is probably associated with high ratios of intracellular accumulation, which were 50- to 100-fold higher than that found for rifampin. Further studies on intracellular distribution of KRM-1648 and on the sites of actual interaction between the drug and bacteria residing in macrophages are necessary, as well as evaluation of combined effects of KRM-1648 with other drugs in long-term macrophage culture experiments. PMID:8726023

  13. In vitro Anti-mycobacterial activity of selected medicinal plants against Mycobacterium tuberculosis and Mycobacterium bovis Strains

    PubMed Central

    2013-01-01

    Background Tuberculosis (TB) is a global burden with one –third of the world’s population infected with the pathogen Mycobacterium tuberculosis complex and annually 1.4 million deaths occur due to the disease. This high incidence of infection and the increased rate of multi-drug resistant and extensively-drug resistant strains of the organism further complicated the problem of TB control and have called for an urgent need to develop new anti-TB drugs from plants. In this study, the in vitro activity of root of Calpurnia aurea, seeds of Ocimum basilicum, leaves of Artemisia abyssinica, Croton macrostachyus, and Eucalyptus camaldulensis were evaluated against M. tuberculosis and M. bovis strains. Methods Five Ethiopian medicinal plants, root of Calpurnia aurea, seeds of Ocimum basilicum, leaves of Artemisia abyssinica, Croton macrostachyus, and Eucalyptus camaldulensis used locally for the management of TB. They were investigated for in vitro antimycobacterial activity against M. tuberculosis and M. bovis strains. 80% methanolic extracts of the plant materials were obtained by maceration. The antimycobacterial activity was determined using 96 wells of microplate with the help of visual Resazurin Microtiter Assay. Results The crude 80% methanolic extracts of the root of C. aurea, seeds of O. basilicum, and leaves of A. abyssinica, C. macrostachyus, and E. camaldulensis had anti-mycobacterial activity with minimum inhibitory concentration (MIC) ranging from 6.25–100 μg/mL. The MIC of 80% methanol extracts in the order mentioned above ranged 25-100 μg/ml and 12.5-75 μg/mL, 25–100 μg/mL and 25–50 μg/mL, 6.25-50 μg/mL and 12.5-50 μg/mL, 12.5-100 μg/mL and 18.25-50 μg/mL and 6.25-50 μg/mL and 12.5-50 μg/mL, respectively for M. tuberculosis and M. bovis strains. Conclusions The results support the local use of these plants in the treatment of TB and it is suggested that these plants may have therapeutic value in the treatment of TB. However

  14. Mycobacterium tuberculosis FtsX extracellular domain activates the peptidoglycan hydrolase, RipC

    PubMed Central

    Mavrici, Daniela; Marakalala, Mohlopheni J.; Holton, James M.; Prigozhin, Daniil M.; Gee, Christine L.; Zhang, Yanjia J.; Rubin, Eric J.; Alber, Tom

    2014-01-01

    Bacterial growth and cell division are coordinated with hydrolysis of the peptidoglycan (PG) layer of the cell wall, but the mechanisms of regulation of extracellular PG hydrolases are not well understood. Here we report the biochemical, structural, and genetic analysis of the Mycobacterium tuberculosis homolog of the transmembrane PG-hydrolase regulator, FtsX. The purified FtsX extracellular domain binds the PG peptidase Rv2190c/RipC N-terminal segment, causing a conformational change that activates the enzyme. Deletion of ftsEX and ripC caused similar phenotypes in Mycobacterium smegmatis, as expected for genes in a single pathway. The crystal structure of the FtsX extracellular domain reveals an unprecedented fold containing two lobes connected by a flexible hinge. Mutations in the hydrophobic cleft between the lobes reduce RipC binding in vitro and inhibit FtsX function in M. smegmatis. These studies suggest how FtsX recognizes RipC and support a model in which a conformational change in FtsX links the cell division apparatus with PG hydrolysis. PMID:24843173

  15. Comparison of activities of rifapentine and rifampin against Mycobacterium tuberculosis residing in human macrophages.

    PubMed Central

    Mor, N; Simon, B; Mezo, N; Heifets, L

    1995-01-01

    The activities of rifapentine and rifampin against Mycobacterium tuberculosis residing in human monocyte-derived macrophages were determined. The MICs and MBCs of rifapentine for intracellular bacteria were two- to fourfold lower than those of rifampin. For extracellular bacteria, this difference was less noticeable. Nevertheless, the more favorable pharmacokinetics of rifapentine over rifampin was addressed in other experimental models. These models showed substantial differences after short pulsed exposures of the infected macrophages to the drugs and when the infected macrophages were exposed to changing drug concentrations that imitated the pharmacokinetic curves observed in blood. Once-a-week exposures to rifapentine concentrations equivalent to those attained in blood after one 600-mg dose resulted during the first week in a dramatic decline in the number of bacteria, and this decline was maintained at a minimal level for a period of four weeks. The results of this study have shown the suitability of rifapentine for intermittent-treatment regimens. The prolonged effect of rifapentine found in this study may be associated with high ratios of intracellular accumulation, which were four- to fivefold higher than those found for rifampin. Further studies on the intracellular distribution of rifamycins and on the sites of actual interaction between the drugs and bacteria residing in macrophages are necessary. PMID:8540718

  16. Structure-activity relationships of 2-aminothiazoles effective against Mycobacterium tuberculosis

    PubMed Central

    Meissner, Anja; Boshoff, Helena I.; Vasan, Mahalakshmi; Duckworth, Benjamin P.; Barry, Clifton E.; Aldrich, Courtney C.

    2013-01-01

    A series of 2-aminothiazoles was synthesized based on a HTS scaffold from a whole-cell screen against Mycobacterium tuberculosis (Mtb). The SAR shows the central thiazole moiety and the 2-pyridyl moiety at C-4 of the thiazole are intolerant to modification. However, the N-2 position of the aminothiazole exhibits high flexibility and we successfully improved the antitubercular activity of the initial hit by more than 128-fold through introduction of substituted benzoyl groups at this position. N-(3-Chlorobenzoyl)-4-(2-pyridinyl)-1,3-thiazol-2-amine (55) emerged as one of the most promising analogues with a MIC of 0.024 μM or 0.008 μg/mL in 7H9 media and therapeutic index of nearly ~300. However, 55 is rapidly metabolized by human liver microsomes (t1/2 = 28 min) with metabolism occurring at the invariant aminothiazole moiety and Mtb develops spontaneous resistance with a high frequency of ~10−5. PMID:24075144

  17. Mycobacterium tuberculosis EsxH inhibits ESCRT-dependent CD4(+) T-cell activation.

    PubMed

    Portal-Celhay, Cynthia; Tufariello, JoAnn M; Srivastava, Smita; Zahra, Aleena; Klevorn, Thais; Grace, Patricia S; Mehra, Alka; Park, Heidi S; Ernst, Joel D; Jacobs, William R; Philips, Jennifer A

    2016-12-05

    Mycobacterium tuberculosis (Mtb) establishes a persistent infection, despite inducing antigen-specific T-cell responses. Although T cells arrive at the site of infection, they do not provide sterilizing immunity. The molecular basis of how Mtb impairs T-cell function is not clear. Mtb has been reported to block major histocompatibility complex class II (MHC-II) antigen presentation; however, no bacterial effector or host-cell target mediating this effect has been identified. We recently found that Mtb EsxH, which is secreted by the Esx-3 type VII secretion system, directly inhibits the endosomal sorting complex required for transport (ESCRT) machinery. Here, we showed that ESCRT is required for optimal antigen processing; correspondingly, overexpression and loss-of-function studies demonstrated that EsxH inhibited the ability of macrophages and dendritic cells to activate Mtb antigen-specific CD4(+) T cells. Compared with the wild-type strain, the esxH-deficient strain induced fivefold more antigen-specific CD4(+) T-cell proliferation in the mediastinal lymph nodes of mice. We also found that EsxH undermined the ability of effector CD4(+) T cells to recognize infected macrophages and clear Mtb. These results provide a molecular explanation for how Mtb impairs the adaptive immune response.

  18. Aminopyrazolo[1,5-a]pyrimidines as potential inhibitors of Mycobacterium tuberculosis: Structure activity relationships and ADME characterization.

    PubMed

    Soares de Melo, Candice; Candice, Soares de Melo; Feng, Tzu-Shean; van der Westhuyzen, Renier; Gessner, Richard K; Street, Leslie J; Morgans, Garreth L; Warner, Digby F; Moosa, Atica; Naran, Krupa; Lawrence, Nina; Boshoff, Helena I M; Barry, Clifton E; Harris, C John; Gordon, Richard; Chibale, Kelly

    2015-11-15

    Whole-cell high-throughput screening of a diverse SoftFocus library against Mycobacterium tuberculosis (Mtb) generated a novel aminopyrazolo[1,5-a]pyrimidine hit series. The synthesis and structure activity relationship studies identified compounds with potent antimycobacterial activity. The SAR of over 140 compounds shows that the 2-pyridylmethylamine moiety at the C-7 position of the pyrazolopyrimidine scaffold was important for Mtb activity, whereas the C-3 position offered a higher degree of flexibility. The series was also profiled for in vitro cytotoxicity and microsomal metabolic stability as well as physicochemical properties. Consequently liabilities to be addressed in a future lead optimization campaign have been identified.

  19. Unusual presentation of tuberculosis in chronic hemodialysis patients.

    PubMed

    Amedia, C; Oettinger, C W

    1977-08-01

    Four patients developed miliary tuberculosis while undergoing chronic hemodialysis. Two patients had diabetes mellitus. Three of the four patients were hemodialyzed 18--24 months prior to the onset of symptoms. Signs and symptoms included prolonged fever, pleural effusion, pericarditis with pericardial effusion, abdominal pain, weight loss, and ascites. All patients were PPD negative and without historical or radiographic evidence of latent tuberculosis. Disseminated tuberculosis was proven at autopsy in three patients. M. tuberculosis was eventually recovered from pleural fluid and urine in the fourth patient. The immune deficiencies of chronic renal failure and diabetes mellitus are suspected predisposing factors to the development of miliary tuberculosis in these patients.

  20. Crystal Structure and Activity Studies of the Mycobacterium tuberculosis β-Lactamase Reveal Its Critical Role in Resistance to β-Lactam Antibiotics

    PubMed Central

    Wang, Feng; Cassidy, Craig; Sacchettini, James C.

    2006-01-01

    β-Lactam antibiotics are extremely effective in disrupting the synthesis of the bacterial cell wall in both gram-positive and gram-negative bacteria. However, they are ineffective against Mycobacterium tuberculosis, due to the production of a β-lactamase enzyme encoded on the chromosome of M. tuberculosis that degrades these antibiotics. Indeed, recent studies have demonstrated that deletion of the blaC gene, the only gene encoding a β-lactamase in M. tuberculosis, or inhibition of the encoded enzyme resulted in significantly increased sensitivity to β-lactam antibiotics. In this paper we present a biochemical and structural characterization of M. tuberculosis BlaC. Recombinant BlaC shows a broad range of specificity with almost equal penicillinase and cepholothinase activity. While clavulanate is a mechanism-based inhibitor to class A β-lactamase with high potency (typically Ki < 0.1 μM), it is a relatively poor inhibitor of the M. tuberculosis BlaC (Ki = 2.4 μM). The crystal structure of the enzyme, determined at a resolution of 1.7 Å, shows that the overall fold of the M. tuberculosis enzyme is similar to other class A β-lactamases. There are, however, several distinct features of the active site, such as the amino acid substitutions N132G, R164A, R244A, and R276E, that explain the broad specificity of the enzyme, relatively low penicillinase activity, and resistance to clavulanate. PMID:16870770

  1. Structure-activity relationships for a series of quinoline-based compounds active against replicating and nonreplicating Mycobacterium tuberculosis.

    PubMed

    Lilienkampf, Annamaria; Mao, Jialin; Wan, Baojie; Wang, Yuehong; Franzblau, Scott G; Kozikowski, Alan P

    2009-04-09

    Tuberculosis (TB) remains as a global pandemic that is aggravated by a lack of health care, the spread of HIV, and the emergence of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) strains. New anti-TB drugs are urgently required to shorten the long 6-12 month treatment regimen and to battle drug-resistant Mtb strains. We have identified several potent quinoline-based anti-TB compounds, bearing an isoxazole containing side-chain. The most potent compounds, 7g and 13, exhibited submicromolar activity against the replicating bacteria (R-TB), with minimum inhibitory concentrations (MICs) of 0.77 and 0.95 microM, respectively. In general, these compounds also had micromolar activity against the nonreplicating persistent bacteria (NRP-TB) and did not show toxicity on Vero cells up to 128 microM concentration. Compounds 7g and 13 were shown to retain their anti-TB activity against rifampin, isoniazid, and streptomycin resistant Mtb strains. The results suggest that quinoline-isoxazole-based anti-TB compounds are promising leads for new TB drug development.

  2. [The diagnosis of pulmonary tuberculosis].

    PubMed

    Koyama, Sekiya; Sakaguchi, Nobuki; Hotta, Jyunnichi

    2012-08-01

    Mycobacterium tuberculosis (M. tuberculosis) infects all organs in the body; however, lung infection is the primary lesion. The total number of infections is decreasing, but the percentage of infections in older people is rising. Because this disease is due to infection with M. tuberculosis, the diagnosis requires the presence of M. tuberculosis. Chest X-ray and CT are very powerful tools to suggest the presence of M. tuberculosis infection. Pathological examination of the tissues also shows the typical findings of M. tuberculosis infection; however, the presence of the bacterium was not proven in certain cases of M. tuberculosis infection, and especially in cases of latent infection. Recently, the whole-blood interferon--gamma test (QuantiFERON-TB, QFT) became more popular than the tuberculin skin test. It is reported that the specificity and sensitivity of QFT are similar to or better than the tuberculin skin test. However, it should be noted that QFT positive does not automatically lead to a diagnosis of active M. tuberculosis infection and that QFT is one of the supplementary tests in the diagnosis of M. tuberculosis infection. Currently, massive infection with M. tuberculosis is increasing. The precise responsible linkage in massive infection with M. tuberculosis needs DNA polymorphism analysis using variable numbers of tandem repeats (VNTR) or restricted fragment length polymorphism (RFLP).

  3. IL23R(Arg381Gln) functional polymorphism is associated with active pulmonary tuberculosis severity.

    PubMed

    Ben-Selma, Walid; Boukadida, Jalel

    2012-08-01

    The purpose of our study was to investigate the association between a functional single nucleotide polymorphism (SNP) in the interleukin-23 receptor gene (IL23R; rs11209026, 1142 G(wild type) → A(reduced function), Arg381Gln) and disease severity outcome in pulmonary tuberculosis (TB) in the Tunisian population. SNP was investigated in a population of 168 patients with active pulmonary TB (cases were stratified into patients with minimal/moderate lung involvement, i.e., patients with minimal/moderate disease [Pmd], and patients with extensive lung involvement, i.e., patients with active disease [Pad]) and 150 healthy subjects. Genotype analyses were carried out using the PCR-restriction fragment length polymorphism method. We have found that the IL23R reduced-function allele 1142A and genotypes AA and AG were overrepresented, especially in the Pad subgroup compared with the control group (51% versus 18% [P = 10(-8)], 33% versus 5% [P = 10(-8)], and 36% versus 26% [P = 5 × 10(-3)], respectively). Additionally, comparison of the Pad and the Pmd groups showed that the A allele and AA genotype seemed to be associated with 2.79-fold (P = 4 × 10(-5)) and 7.74-fold (P = 10(-5)) increased risks of TB with minimal/moderate lung involvement, respectively. Our results demonstrate that the reduced-function polymorphism 1142G → A encoded by IL23R influences the outcome of disease severity of active pulmonary TB in Tunisian patients.

  4. Oral Vaccination with Heat Inactivated Mycobacterium bovis Activates the Complement System to Protect against Tuberculosis

    PubMed Central

    Garrido, Joseba M.; Aranaz, Alicia; Sevilla, Iker; Villar, Margarita; Boadella, Mariana; Galindo, Ruth C.; Pérez de la Lastra, José M.; Moreno-Cid, Juan A.; Fernández de Mera, Isabel G.; Alberdi, Pilar; Santos, Gracia; Ballesteros, Cristina; Lyashchenko, Konstantin P.; Minguijón, Esmeralda; Romero, Beatriz; de Juan, Lucía; Domínguez, Lucas; Juste, Ramón; Gortazar, Christian

    2014-01-01

    Tuberculosis (TB) remains a pandemic affecting billions of people worldwide, thus stressing the need for new vaccines. Defining the correlates of vaccine protection is essential to achieve this goal. In this study, we used the wild boar model for mycobacterial infection and TB to characterize the protective mechanisms elicited by a new heat inactivated Mycobacterium bovis vaccine (IV). Oral vaccination with the IV resulted in significantly lower culture and lesion scores, particularly in the thorax, suggesting that the IV might provide a novel vaccine for TB control with special impact on the prevention of pulmonary disease, which is one of the limitations of current vaccines. Oral vaccination with the IV induced an adaptive antibody response and activation of the innate immune response including the complement component C3 and inflammasome. Mycobacterial DNA/RNA was not involved in inflammasome activation but increased C3 production by a still unknown mechanism. The results also suggested a protective mechanism mediated by the activation of IFN-γ producing CD8+ T cells by MHC I antigen presenting dendritic cells (DCs) in response to vaccination with the IV, without a clear role for Th1 CD4+ T cells. These results support a role for DCs in triggering the immune response to the IV through a mechanism similar to the phagocyte response to PAMPs with a central role for C3 in protection against mycobacterial infection. Higher C3 levels may allow increased opsonophagocytosis and effective bacterial clearance, while interfering with CR3-mediated opsonic and nonopsonic phagocytosis of mycobacteria, a process that could be enhanced by specific antibodies against mycobacterial proteins induced by vaccination with the IV. These results suggest that the IV acts through novel mechanisms to protect against TB in wild boar. PMID:24842853

  5. Osteoarticular manifestations of Mycobacterium tuberculosis infection.

    PubMed

    Zychowicz, Michael E

    2010-01-01

    Mycobacterium tuberculosis has affected humans for much of our existence. The incidence of global tuberculosis infection continues to rise, especially in concert with HIV coinfection. Many disease processes, such as diabetes, increase the likelihood of tuberculosis infection. Tuberculosis bacteria can infect any bone, joint, tendon, or bursa; however, the most common musculoskeletal site for infection includes the spine and weight-bearing joints of the hip and knee. Many patients who present with osteoarticular tuberculosis infection will have a gradual onset of pain at the site of infection. Many patients who develop a musculoskeletal tuberculosis infection will have no evidence of a pulmonary tuberculosis infection on x-ray film and many will have very mild symptoms with the initial infection. Healthcare providers must remember that many patients who develop tuberculosis infection do not progress to active tuberculosis disease; however, the latent infection may become active with immune compromise.

  6. Spectrum of urogenital tuberculosis.

    PubMed

    Kulchavenya, Ekaterina; Zhukova, Irina; Kholtobin, Denis

    2013-10-01

    Urogenital tuberculosis (UGTB) plays an important role because its complications may be fatal, it significantly reduces quality of life, and it is often associated with AIDS. Diagnosis of UGTB is often delayed. We analyzed 131 case histories of UGTB patients from the years 2009-2011. Gender, age, and the clinical form and main features of the disease were taken into account. The most common form was kidney tuberculosis (74.8%). Isolated kidney tuberculosis (KTB) more often occurs in women: 56.8%. Patients of middle and old age more often showed the stage of cavernous KTB; younger patients had smaller forms. Among all cases, an asymptomatic course was seen in 12.2% and, among cases of KTB, in 15.9%. Every third patient complained of flank pain and dysuria (35.2% and 39.8%, respectively); 17% presented with toxicity symptoms, 9.1% with renal colic, and 7.9% with gross hematuria. Mycobacterium tuberculosis (MTB) in urine was found in 31.8% of cases in all levels of isolated KTB. UGTB has no specific symptom; even sterile pyuria occurs only in 25%. The acute onset of tuberculous orchiepididymitis was seen in 35.7% of patients, hemospermia in 7.1%, and dysuria in 35.7%. The most common complaints for prostate tuberculosis were perineal pain (31.6%), dysuria (also 31.6%), and hemospermia (26.3%). MTB in prostate secretion/ejaculate was revealed in 10.5% of this group. All urogenital tract infections should be suspected as UGTB in patients who are living in a region with a high incidence rate, who have had contact with tuberculosis infection, and who have a recurrence of the disease that is resistant to standard therapy.

  7. 78 FR 36698 - Microbiology Devices; Reclassification of Nucleic Acid-Based Systems for Mycobacterium tuberculosis

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-19

    ... handling specimens and control materials with the possibility of transmission of tuberculosis infection to... materials with the possibility of transmission of tuberculosis infection to health care workers could be... infection in patients with suspected tuberculosis as compared to traditional means of diagnosis....

  8. Pyrido[1,2-a]benzimidazole-based agents active against tuberculosis (TB), multidrug-resistant (MDR) TB and extensively drug-resistant (XDR) TB.

    PubMed

    Pieroni, Marco; Tipparaju, Suresh K; Lun, Shichun; Song, Yang; Sturm, A Willem; Bishai, William R; Kozikowski, Alan P

    2011-02-07

    The struggle against tuberculosis (TB) is still far from over. TB, caused by Mycobacterium tuberculosis, is one of the deadliest infections worldwide. Co-infection with human immunodeficiency virus (HIV) and the emergence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) strains have further increased the burden for this disease. Herein, we report the discovery of 2-(4-chlorobenzyl)-3-methyl-1-oxo-1H,5H-pyrido[1,2-a]benzimidazole-4-carbonitrile as an effective antitubercular agent and the structural modifications of this molecule that have led to analogues with improved potency and lower toxicity. A number of these derivatives were also active at sub-micromolar concentrations against resistant TB strains and devoid of apparent toxicity to Vero cells, thereby underscoring their value as novel scaffolds for the development of new anti-TB drugs.

  9. Bovine Tuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tuberculosis (TB) in animals and humans may result from exposure to bacilli within the Mycobacterium tuberculosis complex (i.e., M. tuberculosis, M. bovis, M. africanum, M. pinnipedii, M. microti, M. caprae, or M. canetti). Mycobacterium bovis is the species most often isolated from tuberculous catt...

  10. Hyperthermostable binding molecules on phage: Assay components for point-of-care diagnostics for active tuberculosis infection.

    PubMed

    Zhao, Ning; Spencer, John; Schmitt, Margaret A; Fisk, John D

    2017-03-15

    Tuberculosis is the leading cause of death from infectious disease worldwide. The low sensitivity, extended processing time, and high expense of current diagnostics are major challenges to the detection and treatment of tuberculosis. Mycobacterium tuberculosis ornithine transcarbamylase (Mtb OTC, Rv1656) has been identified in the urine of patients with active TB infection and is a promising target for point-of-care diagnostics. Specific binding proteins with low nanomolar affinities for Mtb OTC were selected from a phage display library built upon a hyperthermostable Sso7d scaffold. Phage particles displaying Sso7d variants were utilized to generate a sandwich ELISA-based assay for Mtb OTC. The assay response is linear between 2 ng/mL and 125 ng/mL recombinant Mtb OTC and has a limit of detection of 400 pg/mL recombinant Mtb OTC. The assay employing a phage-based detection reagent is comparable to commercially-available antibody-based biosensors. Importantly, the assay maintains functionality at both neutral and basic pH in presence of salt and urea over the range of concentrations typical for human urine. Phage-based diagnostic systems may feature improved physical stability and cost of production relative to traditional antibody-based reagents, without sacrificing specificity and sensitivity.

  11. Immunological activity of a 38-kilodalton protein purified from Mycobacterium tuberculosis.

    PubMed Central

    Young, D; Kent, L; Rees, A; Lamb, J; Ivanyi, J

    1986-01-01

    A 38-kilodalton (kDa) protein antigen from Mycobacterium tuberculosis was purified by monoclonal antibody TB71-based affinity chromatography. This molecule carries two nonoverlapping epitopes recognized by monoclonal antibodies TB71 and TB72, which are expressed substantially more strongly by M. tuberculosis than by Mycobacterium bovis. However, cross-reactive determinants between these two species were revealed on the 38-kDa protein by a rabbit anti-BCG serum. An immunoradiometric assay based on the TB71 and TB72 antibody pair specifically determined 38-kDa-antigen concentrations in mycobacterial extracts. Antibodies in sera from tuberculosis patients estimated by binding to 38-kDa-antigen-coated microtiter plates were positively correlated with TB72 competing titers. Unlike antibodies, T-cell proliferative responses to the 38-kDa protein were expressed equally by 60% of tuberculosis patients and healthy BCG-vaccinated subjects. Similarly, delayed-type hypersensitivity skin reactions were elicited in both M. tuberculosis- and M. bovis-sensitized guinea pigs. The results suggest the immunodominance of the species-specific B-cell and cross-reactive T-cell stimulatory epitopes. Images PMID:2428751

  12. Chemical composition of hexane extract of Citrus aurantifolia and anti-Mycobacterium tuberculosis activity of some of its constituents.

    PubMed

    Sandoval-Montemayor, Nallely E; García, Abraham; Elizondo-Treviño, Elizabeth; Garza-González, Elvira; Alvarez, Laura; del Rayo Camacho-Corona, María

    2012-09-19

    The main aim of this study was to isolate and characterize the active compounds from the hexane extract of the fruit peels of Citrus aurantiifolia, which showed activity against one sensitive and three monoresistant (isoniazid, streptomycin or ethambutol) strains of Mycobacterium tuberculosis H37Rv. The active extract was fractionated by column chromatography, yielding the following major compounds: 5-geranyloxypsoralen (1); 5-geranyloxy-7-methoxycoumarin (2); 5,7-dimethoxycoumarin (3); 5-methoxypsoralen (4); and 5,8-dimethoxypsoralen (5). The structures of these compounds were elucidated by 1D and 2D NMR spectroscopy. In addition, GC-MS analysis of the hexane extract allowed the identification of 44 volatile compounds, being 5,7-dimethoxycoumarin (15.79%), 3-methyl-1,2-cyclopentanedione (8.27%), 1-methoxy-ciclohexene (8.0%), corylone (6.93%), palmitic acid (6.89%), 5,8-dimethoxypsoralen (6.08%), a-terpineol (5.97%), and umbelliferone (4.36%), the major constituents. Four isolated coumarins and 16 commercial compounds identified by GC-MS were tested against M. tuberculosis H37Rv and three multidrug-resistant M. tuberculosis strains using the Microplate Alamar Blue Assay. The constituents that showed activity against all strains were 5 (MICs = 25-50 mg/mL), 1 (MICs = 50-100 mg/mL), palmitic acid (MICs = 25-50 mg/mL), linoleic acid (MICs = 50-100 mg/mL), oleic acid (MICs = 100 mg/mL), 4-hexen-3-one (MICs = 50-100 mg/mL), and citral (MICs = 50-100 mg/mL). Compound 5 and palmitic acid were the most active ones. The antimycobacterial activity of the hexane extract of C. aurantifolia could be attributed to these compounds.

  13. Promotion of a down-modulated lung immune state may be a strategy by M. tuberculosis to foster active disease and persistence.

    PubMed

    Ho, John L; Lapa e Silva, Jose Roberto

    2010-01-01

    One-third of humans carry Mycobacterium tuberculosis, the etiological agent of tuberculosis (TB) where microbe/host immune response interactions result in persistence or active TB. However, immune mediators associated with human TB remain poorly defined. Through a series of comparative studies of lung immune response of TB cases at the time of diagnosis and patients with other infectious lung diseases and volunteers, we found that TB cases expressed significantly higher levels of mediators that counteract Th1-type and innate immunity critical for containment of M. tuberculosis. Despite the concomitant heightened levels of Th1-type mediators, they are likely rendered ineffectual by high levels of intracellular (e.g., SOCS) and extracellular (e.g., IL-10) immune suppressors. These modulators are a direct response to M. tuberculosis as many suppressive factors declined to the levels of controls by 30 days of anti-TB treatment while most Th1-type and innate immune mediators rose above the pre-treatment levels. Parallel laboratory studies and monitored lung alveolar macrophage effector, nitric oxide synthase-2 (being shown critical for killing M. tuberculosis), support that M. tuberculosis actively promotes down-modulatory mediators to counteract Th1-type/innate immunity as an immunopathological strategy. Our studies highlight the potential application of immune mediators as surrogate markers for TB diagnosis or treatment response.

  14. Activity of phosphino palladium(II) and platinum(II) complexes against HIV-1 and Mycobacterium tuberculosis.

    PubMed

    Gama, Ntombenhle H; Elkhadir, Afag Y F; Gordhan, Bhavna G; Kana, Bavesh D; Darkwa, James; Meyer, Debra

    2016-08-01

    Treatment of human immunodeficiency virus (HIV) is currently complicated by increased prevalence of co-infection with Mycobacterium tuberculosis. The development of drug candidates that offer the simultaneous management of HIV and tuberculosis (TB) would be of great benefit in the holistic treatment of HIV/AIDS, especially in sub-Saharan Africa which has the highest global prevalence of HIV-TB coinfection. Bis(diphenylphosphino)-2-pyridylpalladium(II) chloride (1), bis(diphenylphosphino)-2-pyridylplatinum(II) chloride (2), bis(diphenylphosphino)-2-ethylpyridylpalladium(II) chloride (3) and bis(diphenylphosphino)-2-ethylpyridylplatinum(II) (4) were investigated for the inhibition of HIV-1 through interactions with the viral protease. The complexes were subsequently assessed for biological potency against Mycobacterium tuberculosis H37Rv by determining the minimal inhibitory concentration (MIC) using broth microdilution. Complex (3) showed the most significant and competitive inhibition of HIV-1 protease (p = 0.014 at 100 µM). Further studies on its in vitro effects on whole virus showed reduced viral infectivity by over 80 % at 63 µM (p < 0.05). In addition, the complex inhibited the growth of Mycobacterium tuberculosis at an MIC of 5 µM and was non-toxic to host cells at all active concentrations (assessed by tetrazolium dye and real time cell electronic sensing). In vitro evidence is provided here for the possibility of utilizing a single metal-based compound for the treatment of HIV/AIDS and TB.

  15. [A report of outbreaks of pulmonary tuberculosis in two bars].

    PubMed

    Ishibatake, H; Onizuka, R

    1997-11-01

    We experienced small outbreaks of M. tuberculosis infection in two bars. 9 patients were diagnosed as tuberculosis by identifying M. tuberculosis from their sputa. Six of them were regular customers or employees of the bar, one of them was a family members. Each outbreak within the two bars was suspected of the common source of infection, because one patient was a regular customer of the both bars. The analysis of restriction fragment length polymorphism (RFLP) was done on 5 strains of M. tuberculosis which were isolated from five of 9 patients. The result unexpectedly showed that 5 isolates were classified into 3 groups. Within each group, identical fingerprints were shown. It does mean that each outbreak in two bars was originated from independent source. There was also one relapsed case of tuberculosis. He was suspected of relapsed tuberculosis after a period of 7 years because of the similarity of drug resistance compared with his primary tuberculosis. It was cleared up that 3 different strains of M. tuberculosis were concerned with these outbreaks in the two bars. In this case, almost all patients were heavy drinkers, however, liver dysfunction and malnutrition were not recognized among them. These experiences indicate that a place like bar may be a space of infection of M. tuberculosis. We should always keep in mind a spread of tuberculosis in a place like a bar as one of problems in tuberculosis control.

  16. Verapamil increases the bactericidal activity of bedaquiline against Mycobacterium tuberculosis in a mouse model.

    PubMed

    Gupta, Shashank; Tyagi, Sandeep; Bishai, William R

    2015-01-01

    Bedaquiline is a newly approved drug for the treatment of multidrug-resistant tuberculosis, but there are concerns about its safety in humans. We found that the coadministration of verapamil with subinhibitory doses of bedaquiline gave the same bactericidal effect in mice as did the full human bioequivalent bedaquiline dosing. Adding verapamil to bedaquiline monotherapy also protected against the development of resistant mutants in vivo. The adjunctive use of verapamil may permit use of lower doses of bedaquiline to be used and thereby reduce its dose-related toxicities in tuberculosis patients.

  17. Co-existing Pulmonary Tuberculosis and Bronchogenic Carcinoma

    PubMed Central

    Holden, Helen M.; Quinlan, J. J.; Hiltz, J. E.

    1965-01-01

    Eighty patients with carcinoma of the lung have been treated at the Nova Scotia Sanatorium since 1940; in 15, coexisting active pulmonary tuberculosis was present. No characteristic clinical or roentgenological findings indicated that the tuberculous individual also had lung cancer. In four cases cancer was not diagnosed until the lung was examined by the pathologist. In the others a considerable interval elapsed before carcinoma was suspected. Only four patients with known cancer were considered suitable for thoracotomy. In three, an attempt at curative resection was made. One survived over seven years before accidental death; one is alive less than one year after operation; the third died as a result of the surgery. Bronchogenic carcinoma should be suspected in every tuberculous patient over the age of 50; diagnostic investigations should include bronchoscopy and cytological studies of bronchial secretion and sputum. Suspicion of carcinoma in any such patient constitutes an indication for early resection of the tuberculous disease. PMID:5843871

  18. Activity of n-propyl pyrazinoate against pyrazinamide-resistant Mycobacterium tuberculosis: investigations into mechanism of action of and mechanism of resistance to pyrazinamide.

    PubMed

    Speirs, R J; Welch, J T; Cynamon, M H

    1995-06-01

    The mechanism of action of pyrazinamide (PZA) is not known. One hypothesis is that PZA functions as a prodrug of pyrazinoic acid. Susceptibility to PZA correlates with amidase activity of the Mycobacterium tuberculosis isolate in question. PZA-resistant isolates retain susceptibility in vitro to pyrazinoic acid and n-propyl pyrazinoate. Esters of pyrazinoic acid appear to circumvent the requirement for activation by mycobacterial amidase. The MICs of n-propyl pyrazinoate for M. tuberculosis isolates are lower than those of pyrazinoic acid. Further studies to assess the effects of modifications of the alcohol and pyrazine moieties of pyrazinoate esters on in vitro and in vivo antituberculosis activity are under way. This may lead to a candidate compound with enhanced activity against both PZA-susceptible and PZA-resistant M. tuberculosis isolates suitable for clinical development.

  19. Flourensia cernua: Hexane Extracts a Very Active Mycobactericidal Fraction from an Inactive Leaf Decoction against Pansensitive and Panresistant Mycobacterium tuberculosis

    PubMed Central

    Molina-Salinas, Gloria María; Peña-Rodríguez, Luis Manuel; Mata-Cárdenas, Benito David; Escalante-Erosa, Fabiola; González-Hernández, Silvia; Torres de la Cruz, Víctor Manuel; Martínez-Rodríguez, Herminia Guadalupe; Said-Fernández, Salvador

    2011-01-01

    The efficacy of decoction in extracting mycobactericidal compounds from Flourensia cernua (Hojasé) leaves and fractionation with solvents having ascending polarity was compared with that of (i) ethanol extraction by still maceration, extraction with a Soxhlet device, shake-assisted maceration, or ultrasound-assisted maceration, followed by fractionation with n-hexane, ethyl acetate, and n-butanol; (ii) sequential extraction with n-hexane, ethyl acetate, and n-butanol, by still maceration, using a Soxhlet device, shake-assisted maceration, or ultrasound-assisted maceration. The in vitro mycobactericidal activity of each preparation was measured against drug-sensitive (SMtb) and drug-resistant (RMtb) Mycobacterium tuberculosis strains. The results of which were expressed as absolute mycobactericidal activity (AMA). These data were normalized to the ΣAMA of the decoction fraction set. Although decoction was inactive, the anti-RMtb normalized ΣAMA (NAMA) of its fractions was comparable with the anti-RMtb NAMA of the still maceration extracts and significantly higher than the anti-SMtb and anti-RMtb NAMAs of every other ethanol extract and serial extract and fraction. Hexane extracted, from decoction, material having 55.17% and 92.62% of antituberculosis activity against SMtb and RMtb, respectively. Although the mycobactericidal activity of decoction is undetectable; its efficacy in extracting F. cernua active metabolites against M. tuberculosis is substantially greater than almost all pharmacognostic methods. PMID:21584254

  20. Cost-effectiveness of active case-finding of household contacts of pulmonary tuberculosis patients in a low HIV, tuberculosis-endemic urban area of Lima, Peru.

    PubMed

    Shah, L; Rojas, M; Mori, O; Zamudio, C; Kaufman, J S; Otero, L; Gotuzzo, E; Seas, C; Brewer, T F

    2017-04-01

    We compared the cost-effectiveness (CE) of an active case-finding (ACF) programme for household contacts of tuberculosis (TB) cases enrolled in first-line treatment to routine passive case-finding (PCF) within an established national TB programme in Peru. Decision analysis was used to model detection of TB in household contacts through: (1) self-report of symptomatic cases for evaluation (PCF), (2) a provider-initiated ACF programme, (3) addition of an Xpert MTB/RIF diagnostic test for a single sputum sample from household contacts, and (4) all strategies combined. CE was calculated as the incremental cost-effectiveness ratio (ICER) in terms of US dollars per disability-adjusted life years (DALYs) averted. Compared to PCF alone, ACF for household contacts resulted in an ICER of $2155 per DALY averted. The addition of the Xpert MTB/RIF diagnostic test resulted in an ICER of $3275 per DALY averted within a PCF programme and $3399 per DALY averted when an ACF programme was included. Provider-initiated ACF of household contacts in an urban setting of Lima, Peru can be highly cost-effective, even including costs to seek out contacts and perform an Xpert/MTB RIF test. ACF including Xpert MTB/RIF was not cost-effective if TB cases detected had high rates of default from treatment or poor outcomes.

  1. Preclinical testing of the nitroimidazopyran PA-824 for activity against Mycobacterium tuberculosis in a series of in vitro and in vivo models.

    PubMed

    Lenaerts, Anne J; Gruppo, Veronica; Marietta, Karen S; Johnson, Christine M; Driscoll, Diane K; Tompkins, Nicholas M; Rose, Jerry D; Reynolds, Robert C; Orme, Ian M

    2005-06-01

    This study extends earlier reports regarding the in vitro and in vivo efficacies of the nitroimidazopyran PA-824 against Mycobacterium tuberculosis. PA-824 was tested in vitro against a broad panel of multidrug-resistant clinical isolates and was found to be highly active against all isolates (MIC<1 microg/ml). The activity of PA-824 against M. tuberculosis was also assessed grown under conditions of oxygen depletion. PA-824 showed significant activity at 2, 10, and 50 microg/ml, similar to that of metronidazole, in a dose-dependent manner. In a short-course mouse infection model, the efficacy of PA-824 at 50, 100, and 300 mg/kg of body weight formulated in methylcellulose or cyclodextrin/lecithin after nine oral treatments was compared with those of isoniazid, rifampin, and moxifloxacin. PA-824 at 100 mg/kg in cyclodextrin/lecithin was as active as moxifloxacin at 100 mg/kg and isoniazid at 25 mg/kg and was slightly more active than rifampin at 20 mg/kg. Long-term treatment with PA-824 at 100 mg/kg in cyclodextrin/lecithin reduced the bacterial load below 500 CFU in the lungs and spleen. No significant differences in activity between PA-824 and the other single drug treatments tested (isoniazid at 25 mg/kg, rifampin at 10 mg/kg, gatifloxacin at 100 mg/kg, and moxifloxacin at 100 mg/kg) could be observed. In summary, its good activity in in vivo models, as well as its activity against multidrug-resistant M. tuberculosis and against M. tuberculosis isolates in a potentially latent state, makes PA-824 an attractive drug candidate for the therapy of tuberculosis. These data indicate that there is significant potential for effective oral delivery of PA-824 for the treatment of tuberculosis.

  2. In vitro activity of rifampicin and verapamil combination in multidrug-resistant mycobacterium tuberculosis.

    PubMed

    Demitto, Fernanda de Oliveira; do Amaral, Renata Claro Ribeiro; Maltempe, Flaviane Granero; Siqueira, Vera Lúcia Dias; Scodro, Regiane Bertin de Lima; Lopes, Mariana Aparecida; Caleffi-Ferracioli, Katiany R; Canezin, Pedro Henrique; Cardoso, Rosilene Fressatti

    2015-01-01

    The aim of the present study was to evaluate the effect of the combination of rifampicin (RIF) and verapamil (VP) against the Mycobacterium tuberculosis H37Rv reference strain and six multidrug-resistant (MDR) M. tuberculosis clinical isolates by determining Time-Kill Curves and the ability to efflux drug by fluorometry. The RIF+VP combination showed synergism in one MDR clinical isolate. For the other five MDR clinical isolates, the drug combination showed no interaction. The MDR clinical isolate had lower ethidium bromide (EtBr) accumulation when exposed to the RIF+VP combination, compared with RIF and VP exposure alone. The other MDR clinical isolates showed no significant difference in EtBr accumulation. These results suggest greater efflux action in one of the MDR clinical isolates compared with the M. tuberculosis H37Rv reference strain. The other five MDR isolates may have additional mechanisms of drug resistance to RIF. The use of the RIF+VP combination made one MDR bacillus more susceptible to RIF probably by inhibiting efflux pumps, and this combination therapy, in some cases, may contribute to a reduction of resistance to RIF in M. tuberculosis.

  3. Mycobacterium tuberculosis inhibits neutrophil apoptosis, leading to delayed activation of naive CD4 T cells.

    PubMed

    Blomgran, Robert; Desvignes, Ludovic; Briken, Volker; Ernst, Joel D

    2012-01-19

    Mycobacterium tuberculosis promotes its replication by inhibiting the apoptosis of infected macrophages. A proapoptotic M. tuberculosis mutant lacking nuoG, a subunit of the type I NADH dehydrogenase complex, exhibits attenuated growth in vivo, indicating that this virulence mechanism is essential. We show that M. tuberculosis also suppresses neutrophil apoptosis. Compared to wild-type, the nuoG mutant spread to a larger number of lung phagocytic cells. Consistent with the shorter lifespan of infected neutrophils, infection with the nuoG mutant resulted in fewer bacteria per infected neutrophil, accelerated bacterial acquisition by dendritic cells, earlier trafficking of these dendritic cells to lymph nodes, and faster CD4 T cell priming. Neutrophil depletion abrogated accelerated CD4 T cell priming by the nuoG mutant, suggesting that inhibiting neutrophil apoptosis delays adaptive immunity in tuberculosis. Thus, pathogen modulation of apoptosis is beneficial at multiple levels, and enhancing phagocyte apoptosis promotes CD4 as well as CD8 T cell responses.

  4. 38 CFR 3.370 - Pulmonary tuberculosis shown by X-ray in active service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... connection for pulmonary tuberculosis. When under consideration, all available service department films and subsequent films will be secured and read by specialists at designated stations who should have a current examination report and X-ray. Resulting interpretations of service films will be accorded the...

  5. 38 CFR 3.370 - Pulmonary tuberculosis shown by X-ray in active service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... connection for pulmonary tuberculosis. When under consideration, all available service department films and subsequent films will be secured and read by specialists at designated stations who should have a current examination report and X-ray. Resulting interpretations of service films will be accorded the...

  6. 38 CFR 3.370 - Pulmonary tuberculosis shown by X-ray in active service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... connection for pulmonary tuberculosis. When under consideration, all available service department films and subsequent films will be secured and read by specialists at designated stations who should have a current examination report and X-ray. Resulting interpretations of service films will be accorded the...

  7. 38 CFR 3.370 - Pulmonary tuberculosis shown by X-ray in active service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... connection for pulmonary tuberculosis. When under consideration, all available service department films and subsequent films will be secured and read by specialists at designated stations who should have a current examination report and X-ray. Resulting interpretations of service films will be accorded the...

  8. miRNA Signatures in Sera of Patients with Active Pulmonary Tuberculosis

    PubMed Central

    Valente, Ilaria C.; Norbis, Luca; Sotgiu, Giovanni; Bosu, Roberta; Ambrosi, Alessandro; Codecasa, Luigi R.; Goletti, Delia; Matteelli, Alberto; Ntinginya, Elias N.; Aloi, Francesco; Heinrich, Norbert; Reither, Klaus; Cirillo, Daniela M.

    2013-01-01

    Several studies showed that assessing levels of specific circulating microRNAs (miRNAs) is a non-invasive, rapid, and accurate method for diagnosing diseases or detecting alterations in physiological conditions. We aimed to identify a serum miRNA signature to be used for the diagnosis of tuberculosis (TB). To account for variations due to the genetic makeup, we enrolled adults from two study settings in Europe and Africa. The following categories of subjects were considered: healthy (H), active pulmonary TB (PTB), active pulmonary TB, HIV co-infected (PTB/HIV), latent TB infection (LTBI), other pulmonary infections (OPI), and active extra-pulmonary TB (EPTB). Sera from 10 subjects of the same category were pooled and, after total RNA extraction, screened for miRNA levels by TaqMan low-density arrays. After identification of “relevant miRNAs”, we refined the serum miRNA signature discriminating between H and PTB on individual subjects. Signatures were analyzed for their diagnostic performances using a multivariate logistic model and a Relevance Vector Machine (RVM) model. A leave-one-out-cross-validation (LOOCV) approach was adopted for assessing how both models could perform in practice. The analysis on pooled specimens identified selected miRNAs as discriminatory for the categories analyzed. On individual serum samples, we showed that 15 miRNAs serve as signature for H and PTB categories with a diagnostic accuracy of 82% (CI 70.2–90.0), and 77% (CI 64.2–85.9) in a RVM and a logistic classification model, respectively. Considering the different ethnicity, by selecting the specific signature for the European group (10 miRNAs) the diagnostic accuracy increased up to 83% (CI 68.1–92.1), and 81% (65.0–90.3), respectively. The African-specific signature (12 miRNAs) increased the diagnostic accuracy up to 95% (CI 76.4–99.1), and 100% (83.9–100.0), respectively. Serum miRNA signatures represent an interesting source of biomarkers for TB disease with the

  9. Thiophenecarboxamide Derivatives Activated by EthA Kill Mycobacterium tuberculosis by Inhibiting the CTP Synthetase PyrG

    PubMed Central

    Mori, Giorgia; Chiarelli, Laurent R.; Esposito, Marta; Makarov, Vadim; Bellinzoni, Marco; Hartkoorn, Ruben C.; Degiacomi, Giulia; Boldrin, Francesca; Ekins, Sean; de Jesus Lopes Ribeiro, Ana Luisa; Marino, Leonardo B.; Centárová, Ivana; Svetlíková, Zuzana; Blaško, Jaroslav; Kazakova, Elena; Lepioshkin, Alexander; Barilone, Nathalie; Zanoni, Giuseppe; Porta, Alessio; Fondi, Marco; Fani, Renato; Baulard, Alain R.; Mikušová, Katarína; Alzari, Pedro M.; Manganelli, Riccardo; de Carvalho, Luiz Pedro S.; Riccardi, Giovanna; Cole, Stewart T.; Pasca, Maria Rosalia

    2015-01-01

    Summary To combat the emergence of drug-resistant strains of Mycobacterium tuberculosis, new antitubercular agents and novel drug targets are needed. Phenotypic screening of a library of 594 hit compounds uncovered two leads that were active against M. tuberculosis in its replicating, non-replicating, and intracellular states: compounds 7947882 (5-methyl-N-(4-nitrophenyl)thiophene-2-carboxamide) and 7904688 (3-phenyl-N-[(4-piperidin-1-ylphenyl)carbamothioyl]propanamide). Mutants resistant to both compounds harbored mutations in ethA (rv3854c), the gene encoding the monooxygenase EthA, and/or in pyrG (rv1699) coding for the CTP synthetase, PyrG. Biochemical investigations demonstrated that EthA is responsible for the activation of the compounds, and by mass spectrometry we identified the active metabolite of 7947882, which directly inhibits PyrG activity. Metabolomic studies revealed that pharmacological inhibition of PyrG strongly perturbs DNA and RNA biosynthesis, and other metabolic processes requiring nucleotides. Finally, the crystal structure of PyrG was solved, paving the way for rational drug design with this newly validated drug target. PMID:26097035

  10. Strong In Vitro Activities of Two New Rifabutin Analogs against Multidrug-Resistant Mycobacterium tuberculosis ▿ †

    PubMed Central

    García, Ana-Belén; Palacios, Juan J.; Ruiz, María-Jesús; Barluenga, José; Aznar, Fernando; Cabal, María-Paz; García, José María; Díaz, Natalia

    2010-01-01

    Two new rifabutin analogs, RFA-1 and RFA-2, show high in vitro antimycobacterial activities against Mycobacterium tuberculosis. MIC values of RFA-1 and RFA-2 were ≤0.02 μg/ml against rifamycin-susceptible strains and 0.5 μg/ml against a wide selection of multidrug-resistant strains, compared to ≥50 μg/ml for rifampin and 10 μg/ml for rifabutin. Molecular dynamic studies indicate that the compounds may exert tighter binding to mutants of RNA polymerase that have adapted to the rifamycins. PMID:20855731

  11. [Health examination in future at the era of low tuberculosis incidence--from contacts examination toward active epidemiological studies].

    PubMed

    Maeda, Hideo; Shirai, Chika

    2013-03-01

    Japan is still "intermediate burden" country as medium-incidence of tuberculosis (TB). But the incidence of TB varies by public health units. The priority for TB control would be lowering in the areas where the incidence of TB is relatively low. In addition, younger age groups get low prevalence of TB infection than elderly persons. As a result, fewer experiences for TB diagnosis and treatment in the hospital and the medical facility would cause the delay in the detection of TB patients which eventually cause outbreaks. Although there are differences in population density and population mobility between urban and rural areas, the socially economic vulnerable patients and foreign patients are the common risks. Any public health units' policies of TB should correspond to the individual situation. At the era of low tuberculosis incidence, the infection risk is to be "From ubiquitous to the uneven distribution". This makes TB detection much more difficult. At this symposium, each speaker presented the case for actually experienced with QFT test and/or VNTR analysis. They mainly focused on the paradigm shift in TB control which is indispensable for resolving the gaps in regional differences and the differences in diagnostic capability. Although the cases in this symposium were not for the low incidence situation, the pioneering approaches presented here would boost the future application of QFT and VNTR analysis nationwide. The discussions also partially covered the technical infrastructure for molecular epidemiology which covers the whole country. By making full use of QFT test and VNTR analysis as a contact screening tool, we can appropriately understand the risk of TB infection in the region from a buildup of bacteria and patient information. Now is the time to prepare for. Active surveillance of TB by this way would clarify the risk of the disease and lead to the advocacy essential for the resolution. 1. Current situation and challenge of contact survey by using QFT

  12. Efficient heterologous expression and one-step purification of fully active c-terminal histidine-tagged uridine monophosphate kinase from Mycobacterium tuberculosis.

    PubMed

    Penpassakarn, Praweenuch; Chaiyen, Pimchai; Palittapongarnpim, Prasit

    2011-11-01

    Tuberculosis has long been recognized as one of the most significant public health problems. Finding novel antituberculous drugs is always a necessary approach for controlling the disease. Mycobacterium tuberculosis pyrH gene (Rv2883c) encodes for uridine monophosphate kinase (UMK), which is a key enzyme in the uridine nucleotide interconversion pathway. The enzyme is essential for M. tuberculosis to sustain growth and hence is a potential drug target. In this study, we have developed a rapid protocol for production and purification of M. tuberculosis UMK by cloning pyrH (Rv2883c) of M. tuberculosis H37Rv with the addition of 6-histidine residues to the C-terminus of the protein, and expressing in E. coli BL21-CodonPlus (DE3)-RIPL using an auto-induction medium. The enzyme was efficiently purified by a single-step TALON cobalt affinity chromatography with about 8 fold increase in specific activity, which was determined by a coupled assay with the pyruvate kinase and lactate dehydrogenase. The molecular mass of monomeric UMK was 28.2 kDa and that of the native enzyme was 217 kDa. The enzyme uses UMP as a substrate but not CMP and TMP and activity was enhanced by GTP. Measurements of enzyme kinetics revealed the kcat value of 7.6 +/- 0.4 U mg(-1) or 0.127 +/- 0.006 sec(-1).The protocol reported here can be used for expression of M. tuberculosis UMK in large quantity for formulating a high throughput target-based assay for screening anti-tuberculosis UMK compounds.

  13. Moxifloxacin (BAY12-8039), a New 8-Methoxyquinolone, Is Active in a Mouse Model of Tuberculosis

    PubMed Central

    Miyazaki, Eishi; Miyazaki, Miki; Chen, Jong Min; Chaisson, Richard E.; Bishai, William R.

    1999-01-01

    Moxifloxacin (BAY12-8039) is a new 8-methoxyquinolone shown to be active against Mycobacterium tuberculosis in vitro. We tested moxifloxacin for activity in mice against M. tuberculosis CSU93, a highly virulent, recently isolated clinical strain. The MIC of moxifloxacin for the CSU93 strain was 0.25 μg/ml. The serum moxifloxacin concentration after oral administration in mice peaked within 0.25 h, reaching 7.8 μg/ml with doses of 100 mg/kg of body weight; the maximum concentration and the analysis of the area under the concentration-time curve revealed dose dependency. When mice were infected with a sublethal inoculum of mycobacteria and then treated with moxifloxacin at 100 mg/kg per day for 8 weeks, the log10 CFU counts in the organs of treated mice were significantly lower than those for the control group (0.6 ± 0.2 versus 5.6 ± 0.3 in the lungs and 1.5 ± 0.7 versus 4.9 ± 0.5 in the spleens, respectively; P < 0.001 in both organs). The effectiveness of moxifloxacin monotherapy was comparable to that seen in mice receiving isoniazid alone. Combination therapy with moxifloxacin plus isoniazid was superior to that with moxifloxacin or with isoniazid alone in reducing bacillary counts in the organs studied. Using a sensitive broth-passage subculture method, we demonstrated that 8 weeks of treatment with moxifloxacin (100 mg/kg per day) or with moxifloxacin plus isoniazid (100 mg/kg and 25 mg/kg, respectively, per day) sterilized the lungs in seven of eight and in eight of eight mice, respectively. Among surviving bacilli isolated from animals infected with a high-titer inoculum and treated for 7 weeks with low-dose moxifloxacin (20 mg/kg per day), breakthrough resistance to moxifloxacin was not observed. These results indicate that moxifloxacin is highly effective in reducing M. tuberculosis infection in mice and has activity comparable to that of isoniazid. Combination therapy with moxifloxacin and isoniazid was highly effective, suggesting that moxifloxacin

  14. Reporter phage and breath tests: emerging phenotypic assays for diagnosing active tuberculosis, antibiotic resistance, and treatment efficacy.

    PubMed

    Jain, Paras; Thaler, David S; Maiga, Mamoudou; Timmins, Graham S; Bishai, William R; Hatfull, Graham F; Larsen, Michelle H; Jacobs, William R

    2011-11-15

    The rapid and accurate diagnosis of active tuberculosis (TB) and its drug susceptibility remain a challenge. Phenotypic assays allow determination of antibiotic susceptibilities even if sequence data are not available or informative. We review 2 emerging diagnostic approaches, reporter phage and breath tests, both of which assay mycobacterial metabolism. The reporter phage signal, Green fluorescent protein (GFP) or β-galactosidase, indicates transcription and translation inside the recipient bacilli and its attenuation by antibiotics. Different breath tests assay, (1) exhaled antigen 85, (2) mycobacterial urease activity, and (3) detection by trained rats of disease-specific odor in sputum, have also been developed. When compared with culture, reporter phage assays shorten the time for initial diagnosis of drug susceptibility by several days. Both reporter phage and breath tests have promise as early markers to determine the efficacy of treatment. While sputum often remains smear and Mycobacterium tuberculosis DNA positive early in the course of efficacious antituberculous treatment, we predict that both breath and phage tests will rapidly become negative. If this hypothesis proves correct, phage assays and breath tests could become important surrogate markers in early bactericidal activity (EBA) studies of new antibiotics.

  15. Ligand uptake in Mycobacterium tuberculosis truncated hemoglobins is controlled by both internal tunnels and active site water molecules

    PubMed Central

    Davidge, Kelly S; Singh, Sandip; Bowman, Lesley AH; Tinajero-Trejo, Mariana; Carballal, Sebastián; Radi, Rafael; Poole, Robert K; Dikshit, Kanak; Estrin, Dario A; Marti, Marcelo A; Boechi, Leonardo

    2015-01-01

    Mycobacterium tuberculosis, the causative agent of human tuberculosis, has two proteins belonging to the truncated hemoglobin (trHb) family. Mt-trHbN presents well-defined internal hydrophobic tunnels that allow O 2 and •NO to migrate easily from the solvent to the active site, whereas Mt-trHbO possesses tunnels that are partially blocked by a few bulky residues, particularly a tryptophan at position G8. Differential ligand migration rates allow Mt-trHbN to detoxify •NO, a crucial step for pathogen survival once under attack by the immune system, much more efficiently than Mt-trHbO. In order to investigate the differences between these proteins, we performed experimental kinetic measurements, •NO decomposition, as well as molecular dynamics simulations of the wild type Mt-trHbN and two mutants, VG8F and VG8W. These mutations introduce modifications in both tunnel topologies and affect the incoming ligand capacity to displace retained water molecules at the active site. We found that a single mutation allows Mt-trHbN to acquire ligand migration rates comparable to those observed for Mt-trHbO, confirming that ligand migration is regulated by the internal tunnel architecture as well as by water molecules stabilized in the active site. PMID:26478812

  16. Safety of Resuming Tumor Necrosis Factor Inhibitors in Ankylosing Spondylitis Patients Concomitant with the Treatment of Active Tuberculosis: A Retrospective Nationwide Registry of the Korean Society of Spondyloarthritis Research

    PubMed Central

    Kim, Hye Won; Kwon, Seong Ryul; Jung, Kyong-Hee; Kim, Seong-Kyu; Baek, Han Joo; Seo, Mi Ryung; Bang, So-Young; Lee, Hye-Soon; Suh, Chang-Hee; Jung, Ju Yang; Son, Chang-Nam; Shim, Seung Cheol; Lee, Sang-Hoon; Lee, Seung-Geun; Lee, Yeon-Ah; Lee, Eun Young; Kim, Tae-Hwan

    2016-01-01

    Backgrounds Patients who develop an active tuberculosis infection during tumor necrosis factor (TNF) inhibitor treatment typically discontinue TNF inhibitor and receive standard anti-tuberculosis treatment. However, there is currently insufficient information on patient outcomes following resumption of TNF inhibitor treatment during ongoing anti- tuberculosis treatment. Our study was designed to investigate the safety of resuming TNF inhibitors in ankylosing spondylitis (AS) patients who developed tuberculosis as a complication of the use of TNF inhibitors. Methods Through the nationwide registry of the Korean Society of Spondyloarthritis Research, 3929 AS patients who were prescribed TNF inhibitors were recruited between June 2003 and June 2014 at fourteen referral hospitals. Clinical information was analyzed about the patients who experienced tuberculosis after exposure to TNF inhibitors. The clinical features of resumers and non-resumers of TNF inhibitors were compared and the outcomes of tuberculosis were surveyed individually. Findings Fifty-six AS patients were treated for tuberculosis associated with TNF inhibitors. Among them, 23 patients resumed TNF inhibitors, and these patients were found to be exposed to TNF inhibitors for a longer period of time and experienced more frequent disease flare-up after discontinuation of TNF inhibitors compared with those who did not resume. Fifteen patients resumed TNF inhibitors during anti-tuberculosis treatment (early resumers) and 8 after completion of anti-tuberculosis treatment (late resumers). Median time to resuming TNF inhibitor from tuberculosis was 3.3 and 9.0 months in the early and late resumers, respectively. Tuberculosis was treated successfully in all resumers and did not relapse in any of them during follow-up (median 33.8 [IQR; 20.8–66.7] months). Conclusions Instances of tuberculosis were treated successfully in our AS patients, even when given concomitantly with TNF inhibitors. We suggest that early

  17. High-content screening technology combined with a human granuloma model as a new approach to evaluate the activities of drugs against Mycobacterium tuberculosis.

    PubMed

    Silva-Miranda, Mayra; Ekaza, Euloge; Breiman, Adrien; Asehnoune, Karim; Barros-Aguirre, David; Pethe, Kevin; Ewann, Fanny; Brodin, Priscille; Ballell-Pages, Lluís; Altare, Frédéric

    2015-01-01

    Tuberculosis remains a major health problem due to the emergence of drug-resistant strains of Mycobacterium tuberculosis. Some models have provided valuable information about drug resistance and efficacy; however, the translation of these results into effective human treatments has mostly proven unsuccessful. In this study, we adapted high-content screening (HCS) technology to investigate the activities of antitubercular compounds in the context of an in vitro granuloma model. We observed significant shifts in the MIC50s between the activities of the compounds under extracellular and granuloma conditions.

  18. High-Content Screening Technology Combined with a Human Granuloma Model as a New Approach To Evaluate the Activities of Drugs against Mycobacterium tuberculosis

    PubMed Central

    Silva-Miranda, Mayra; Breiman, Adrien; Asehnoune, Karim; Barros-Aguirre, David; Pethe, Kevin; Ewann, Fanny; Brodin, Priscille; Ballell-Pages, Lluís

    2014-01-01

    Tuberculosis remains a major health problem due to the emergence of drug-resistant strains of Mycobacterium tuberculosis. Some models have provided valuable information about drug resistance and efficacy; however, the translation of these results into effective human treatments has mostly proven unsuccessful. In this study, we adapted high-content screening (HCS) technology to investigate the activities of antitubercular compounds in the context of an in vitro granuloma model. We observed significant shifts in the MIC50s between the activities of the compounds under extracellular and granuloma conditions. PMID:25348525

  19. Multidrug-Resistant Mycobacterium tuberculosis of the Latin American Mediterranean Lineage, Wrongly Identified as Mycobacterium pinnipedii (Spoligotype International Type 863 [SIT863]), Causing Active Tuberculosis in South Brazil

    PubMed Central

    Vasconcelos, Sidra E. G.; Esteves, Leonardo S.; Gomes, Harrison M.; Almeida da Silva, Pedro; Perdigão, João; Portugal, Isabel; Viveiros, Miguel; McNerney, Ruth; Pain, Arnab; Clark, Taane G.; Rastogi, Nalin; Unis, Gisela; Rossetti, Maria Lucia R.

    2015-01-01

    We recently detected the spoligotype patterns of strains of Mycobacterium pinnipedii, a species of the Mycobacterium tuberculosis complex, in sputum samples from nine cases with pulmonary tuberculosis residing in Porto Alegre, South Brazil. Because this species is rarely encountered in humans, we further characterized these nine isolates by additional genotyping techniques, including 24-locus mycobacterial interspersed repetitive-unit–variable-number tandem-repeat (MIRU-VNTR) typing, verification of the loci TbD1, RD9, pks15/1, RDRio, and fbpC, the insertion of IS6110 at a site specific to the M. tuberculosis Latin American Mediterranean (LAM) lineage, and whole-genome sequencing. The combined analysis of these markers revealed that the isolates are in fact M. tuberculosis and more specifically belong to the LAM genotype. Most of these isolates (n = 8) were shown to be multidrug resistant (MDR), which prompted us to perform partial sequencing of the rpoA, rpoB, rpoC, katG, and inhA genes. Seven isolates (77.8%) carried the S315T mutation in katG, and one of these (11%) also presented the C(−17)T single-nucleotide polymorphism (SNP) in inhA. Interestingly, six of the MDR isolates also presented an undescribed insertion of 12 nucleotides (CCA GAA CAA CCC) in codon 516 of rpoB. No putative compensatory mutation was found in either rpoA or rpoC. This is the first report of an M. tuberculosis LAM family strain with a convergent M. pinnipedii spoligotype. These spoligotypes are observed in genotype databases at a modest frequency, highlighting that care must be taken when identifying isolates in the M. tuberculosis complex on the basis of single genetic markers. PMID:26400784

  20. The multistage vaccine H56 boosts the effects of BCG to protect cynomolgus macaques against active tuberculosis and reactivation of latent Mycobacterium tuberculosis infection.

    PubMed

    Lin, Philana Ling; Dietrich, Jes; Tan, Esterlina; Abalos, Rodolfo M; Burgos, Jasmin; Bigbee, Carolyn; Bigbee, Matthew; Milk, Leslie; Gideon, Hannah P; Rodgers, Mark; Cochran, Catherine; Guinn, Kristi M; Sherman, David R; Klein, Edwin; Janssen, Christopher; Flynn, JoAnne L; Andersen, Peter

    2012-01-01

    It is estimated that one-third of the world's population is infected with Mycobacterium tuberculosis. Infection typically remains latent, but it can reactivate to cause clinical disease. The only vaccine, Mycobacterium bovis bacillus Calmette-Guérin (BCG), is largely ineffective, and ways to enhance its efficacy are being developed. Of note, the candidate booster vaccines currently under clinical development have been designed to improve BCG efficacy but not prevent reactivation of latent infection. Here, we demonstrate that administering a multistage vaccine that we term H56 in the adjuvant IC31 as a boost to vaccination with BCG delays and reduces clinical disease in cynomolgus macaques challenged with M. tuberculosis and prevents reactivation of latent infection. H56 contains Ag85B and ESAT-6, which are two of the M. tuberculosis antigens secreted in the acute phase of infection, and the nutrient stress-induced antigen Rv2660c. Boosting with H56/IC31 resulted in efficient containment of M. tuberculosis infection and reduced rates of clinical disease, as measured by clinical parameters, inflammatory markers, and improved survival of the animals compared with BCG alone. Boosted animals showed reduced pulmonary pathology and extrapulmonary dissemination, and protection correlated with a strong recall response against ESAT-6 and Rv2660c. Importantly, BCG/H56-vaccinated monkeys did not reactivate latent infection after treatment with anti-TNF antibody. Our results indicate that H56/IC31 boosting is able to control late-stage infection with M. tuberculosis and contain latent tuberculosis, providing a rationale for the clinical development of H56.

  1. A case of isoniazid-resistant miliary tuberculosis in which tuberculous meningitis paradoxically developed despite systemic improvement.

    PubMed

    Ikegame, Satoshi; Wakamatsu, Kentaro; Fujita, Masaki; Nakanishi, Yoichi; Harada, Mine; Kajiki, Akira

    2011-10-01

    A 63-year-old man with chronic myelomonocytic leukemia was admitted to our hospital with miliary tuberculosis. He received anti-tuberculosis drugs: isoniazid (INH), rifampicin (RFP), ethambutol (EB), and pyrazinamide (PZA). His condition clearly and immediately improved after the therapy, but he experienced a high fever of about 38°C every day from 1 month after the initiation of the therapy. Drug-induced fever and tumor fever were suspected as causes, but the etiology could not be determined. The tuberculosis was identified as an INH-resistant strain, so INH was stopped and levofloxacin (LVFX) was introduced, with streptomycin (SM), in addition to RFP, EB, and PZA. At 2 months after the initiation of the therapy (about one week after the change in the anti-tuberculosis drug regimen), his spinal fluid was examined, given his complaints of headache and vomiting. The spinal fluid analysis revealed invasion of lymphocytic inflammatory cells and high adenosine deaminase activity; the patient was thus diagnosed with tuberculous meningitis. His condition gradually improved after the changing of the anti-tuberculosis drugs. Thus, to summarize, the tuberculous meningitis had worsened paradoxically despite his systemic improvement, although it was successfully treated by the addition of LVFX and SM. We must keep in mind that a potential cause of fever during anti-tuberculosis therapy may be INH-resistant tuberculous meningitis.

  2. Tuberculosis: a breast-feeding challenge.

    PubMed

    Aquilina, Suzanne; Winkelman, Theresa

    2008-01-01

    A recent resurgence of tuberculosis in the world community has brought the disease into the forefront of communicable disease control. Acknowledging the proven benefits of breast-feeding infants, the question of compatibility arises regarding the safety of breast-feeding an infant in the event of active tuberculosis disease in the mother. This article will discuss the emerging trends of tuberculosis disease and review the evidence that addresses the issues of safety while breast-feeding during tuberculosis treatment.

  3. Official American Thoracic Society/Centers for Disease Control and Prevention/Infectious Diseases Society of America Clinical Practice Guidelines: Treatment of Drug-Susceptible Tuberculosis.

    PubMed

    Nahid, Payam; Dorman, Susan E; Alipanah, Narges; Barry, Pennan M; Brozek, Jan L; Cattamanchi, Adithya; Chaisson, Lelia H; Chaisson, Richard E; Daley, Charles L; Grzemska, Malgosia; Higashi, Julie M; Ho, Christine S; Hopewell, Philip C; Keshavjee, Salmaan A; Lienhardt, Christian; Menzies, Richard; Merrifield, Cynthia; Narita, Masahiro; O'Brien, Rick; Peloquin, Charles A; Raftery, Ann; Saukkonen, Jussi; Schaaf, H Simon; Sotgiu, Giovanni; Starke, Jeffrey R; Migliori, Giovanni Battista; Vernon, Andrew

    2016-10-01

    The American Thoracic Society, Centers for Disease Control and Prevention, and Infectious Diseases Society of America jointly sponsored the development of this guideline for the treatment of drug-susceptible tuberculosis, which is also endorsed by the European Respiratory Society and the US National Tuberculosis Controllers Association. Representatives from the American Academy of Pediatrics, the Canadian Thoracic Society, the International Union Against Tuberculosis and Lung Disease, and the World Health Organization also participated in the development of the guideline. This guideline provides recommendations on the clinical and public health management of tuberculosis in children and adults in settings in which mycobacterial cultures, molecular and phenotypic drug susceptibility tests, and radiographic studies, among other diagnostic tools, are available on a routine basis. For all recommendations, literature reviews were performed, followed by discussion by an expert committee according to the Grading of Recommendations, Assessment, Development and Evaluation methodology. Given the public health implications of prompt diagnosis and effective management of tuberculosis, empiric multidrug treatment is initiated in almost all situations in which active tuberculosis is suspected. Additional characteristics such as presence of comorbidities, severity of disease, and response to treatment influence management decisions. Specific recommendations on the use of case management strategies (including directly observed therapy), regimen and dosing selection in adults and children (daily vs intermittent), treatment of tuberculosis in the presence of HIV infection (duration of tuberculosis treatment and timing of initiation of antiretroviral therapy), as well as treatment of extrapulmonary disease (central nervous system, pericardial among other sites) are provided. The development of more potent and better-tolerated drug regimens, optimization of drug exposure for the

  4. Executive Summary: Official American Thoracic Society/Centers for Disease Control and Prevention/Infectious Diseases Society of America Clinical Practice Guidelines: Treatment of Drug-Susceptible Tuberculosis.

    PubMed

    Nahid, Payam; Dorman, Susan E; Alipanah, Narges; Barry, Pennan M; Brozek, Jan L; Cattamanchi, Adithya; Chaisson, Lelia H; Chaisson, Richard E; Daley, Charles L; Grzemska, Malgosia; Higashi, Julie M; Ho, Christine S; Hopewell, Philip C; Keshavjee, Salmaan A; Lienhardt, Christian; Menzies, Richard; Merrifield, Cynthia; Narita, Masahiro; O'Brien, Rick; Peloquin, Charles A; Raftery, Ann; Saukkonen, Jussi; Schaaf, H Simon; Sotgiu, Giovanni; Starke, Jeffrey R; Migliori, Giovanni Battista; Vernon, Andrew

    2016-10-01

    The American Thoracic Society, Centers for Disease Control and Prevention, and Infectious Diseases Society of America jointly sponsored the development of this guideline for the treatment of drug-susceptible tuberculosis, which is also endorsed by the European Respiratory Society and the US National Tuberculosis Controllers Association. Representatives from the American Academy of Pediatrics, the Canadian Thoracic Society, the International Union Against Tuberculosis and Lung Disease, and the World Health Organization also participated in the development of the guideline. This guideline provides recommendations on the clinical and public health management of tuberculosis in children and adults in settings in which mycobacterial cultures, molecular and phenotypic drug susceptibility tests, and radiographic studies, among other diagnostic tools, are available on a routine basis. For all recommendations, literature reviews were performed, followed by discussion by an expert committee according to the Grading of Recommendations, Assessment, Development and Evaluation methodology. Given the public health implications of prompt diagnosis and effective management of tuberculosis, empiric multidrug treatment is initiated in almost all situations in which active tuberculosis is suspected. Additional characteristics such as presence of comorbidities, severity of disease, and response to treatment influence management decisions. Specific recommendations on the use of case management strategies (including directly observed therapy), regimen and dosing selection in adults and children (daily vs intermittent), treatment of tuberculosis in the presence of HIV infection (duration of tuberculosis treatment and timing of initiation of antiretroviral therapy), as well as treatment of extrapulmonary disease (central nervous system, pericardial among other sites) are provided. The development of more potent and better-tolerated drug regimens, optimization of drug exposure for the

  5. Increased Case Notification through Active Case Finding of Tuberculosis among Household and Neighbourhood Contacts in Cambodia

    PubMed Central

    Morishita, Fukushi; Eang, Mao Tan; Nishikiori, Nobuyuki; Yadav, Rajendra-Prasad

    2016-01-01

    Background Globally, there has been growing evidence that suggests the effectiveness of active case finding (ACF) for tuberculosis (TB) in high-risk populations. However, the evidence is still insufficient as to whether ACF increases case notification beyond what is reported in the routine passive case finding (PCF). In Cambodia, National TB Control Programme has conducted nationwide ACF with Xpert MTB/RIF that retrospectively targeted household and neighbourhood contacts alongside routine PCF. This study aims to investigate the impact of ACF on case notifications during and after the intervention period. Methods Using a quasi-experimental cluster randomized design with intervention and control arms, we compared TB case notification during the one-year intervention period with historical baseline cases and trend-adjusted expected cases, and estimated additional cases notified during the intervention period (separately for Year 1 and Year 2 implementation). The proportion of change in case notification was compared between intervention and control districts for Year 1. The quarterly case notification data from all intervention districts were consolidated, aligning different implementation quarters, and separately analysed to explore the additionality. The effect of the intervention on the subsequent case notification during the post-intervention period was also assessed. Results In Year 1, as compared to expected cases, 1467 cases of all forms (18.5%) and 330 bacteriologically-confirmed cases (9.6%) were additionally notified in intervention districts, whereas case notification in control districts decreased by 2.4% and 2.3%, respectively. In Year 2, 2737 cases of all forms (44.3%) and 793 bacteriologically-confirmed cases (38%) were additionally notified as compared to expected cases. The proportions of increase in case notifications from baseline cases and expected cases to intervention period cases were consistently higher in intervention group than in control

  6. Executive summary of the guidelines for the use of interferon-γ release assays in the diagnosis of tuberculosis infection.

    PubMed

    Santin, Miguel; García-García, José-María; Rigau, David; Altet, Neus; Anibarro, Luis; Casas, Irma; Díez, Nuria; García-Gasalla, Mercedes; Martínez-Lacasa, Xavier; Penas, Antón; Pérez-Escolano, Elvira; Sánchez, Francisca; Domínguez, José

    2016-05-01

    Interferon-gamma release assays are widely used for the diagnosis of tuberculosis infection in Spain. However, there is no consensus on their application in specific clinical scenarios. To develop a guideline for their use, a panel of experts comprising specialists in infectious diseases, respiratory diseases, microbiology, pediatrics and preventive medicine, together with a methodologist, conducted a systematic literature search, summarized the findings, rated the quality of the evidence, and formulated recommendations following the GRADE (Grading of Recommendations of Assessment Development and Evaluations) methodology. This document provides evidence-based guidance on the use of interferon-gamma release assays for the diagnosis of tuberculosis infection in patients at the risk of tuberculosis or suspected of having active disease. The guidelines will be applicable to specialist and primary care, and public health.

  7. Executive Summary of the Guidelines for the Use of interferon-gamma Release Assays in the Diagnosis of Tuberculosis Infection.

    PubMed

    Santin, Miguel; García-García, José-María; Rigau, David; Altet, Neus; Anibarro, Luis; Casas, Irma; Díez, Nuria; García-Gasalla, Mercedes; Martínez-Lacasa, Xavier; Penas, Antón; Pérez-Escolano, Elvira; Sánchez, Francisca; Domínguez, José

    2016-09-01

    Interferon-gamma release assays are widely used for the diagnosis of tuberculosis infection in Spain. However, there is no consensus on their application in specific clinical scenarios. To develop a guide-line for their use, a panel of experts comprising specialists in infectious diseases, respiratory diseases, microbiology, pediatrics and preventive medicine, together with a methodologist, conducted a systematic literature search, summarized the findings, rated the quality of the evidence, and formulated recommendations following the Grading of Recommendations of Assessment Development and Evaluations methodology. This document provides evidence-based guidance on the use of interferon-gamma release assays for the diagnosis of tuberculosis infection in patients at risk of tuberculosis or suspected of having active disease. The guidelines will be applicable to specialist and primary care, and public health.

  8. Early dynamics of T helper cell cytokines and T regulatory cells in response to treatment of active Mycobacterium tuberculosis infection.

    PubMed

    Feruglio, S L; Tonby, K; Kvale, D; Dyrhol-Riise, A M

    2015-03-01

    Biomarkers that can identify tuberculosis (TB) disease and serve as markers for efficient therapy are requested. We have studied T cell cytokine production [interferon (IFN)-γ, interleukin (IL)-2, tumour necrosis factor (TNF)-α] and degranulation (CD107a) as well as subsets of CD4(+) T regulatory cells (Tregs ) after in-vitro Mycobacterium tuberculosis (Mtb) antigen stimulation [early secretory antigenic target (ESAT)-6, culture filtrate protein (CFP)-10, antigen 85 (Ag85)] in 32 patients with active tuberculosis (TB) disease throughout 24 weeks of effective TB treatment. A significant decline in the fraction of Mtb-specific total IFN-γ and single IFN-γ-producing T cells was already observed after 2 weeks of treatment, whereas the pool of single IL-2(+) cells increased over time for both CD4(+) and CD8(+) T cells. The Treg subsets CD25(high) CD127(low) , CD25(high) CD147(++) and CD25(high) CD127(low) CD161(+) expanded significantly after Mtb antigen stimulation in vitro at all time-points, whereas the CD25(high) CD127(low) CD39(+) Tregs remained unchanged. The fraction of CD25(high) CD127(low) Tregs increased after 8 weeks of treatment. Thus, we revealed an opposing shift of Tregs and intracellular cytokine production during treatment. This may indicate that functional signatures of the CD4(+) and CD8(+) T cells can serve as immunological correlates of early curative host responses. Whether such signatures can be used as biomarkers in monitoring and follow-up of TB treatment needs to be explored further.

  9. Yield of intensified tuberculosis case-finding activities using Xpert® MTB/RIF among risk groups in Nepal

    PubMed Central

    Baral, S.; Shrestha, P.; Puri, M.; Kandel, S.; Lamichanne, B.; Elsey, H.; Brouwer, M.; Goel, S.; Chinnakali, P.

    2016-01-01

    Setting: Twenty-two districts of Nepal, where intensified case-finding (ICF) activities for tuberculosis (TB) were implemented among risk groups under the TB REACH initiative in collaboration with the National TB Programme from July 2013 to November 2015. Objectives: To assess the yield of TB screening using an algorithm with smear microscopy followed by Xpert® MTB/RIF. Design: A descriptive study using routinely collected data. Results: Of 145 679 individuals screened, 28 574 (19.6%) had presumptive TB; 1239 (4.3%) of these were diagnosed with TB and 1195 (96%) were initiated on anti-tuberculosis treatment. The yield of screening was highest among people living with the human immunodeficiency virus (PLHIV) (6.1%), followed by household contacts (3.5%) and urban slum dwellers (0.5%). Among other risk groups, such as prisoners, factory workers, refugees and individuals with diabetes, the yield was less than 0.5%. The number needed to screen to diagnose an active TB case was 17 for PLHIV, 29 for household contacts and 197 for urban slum dwellers. Of 11 525 patients from ICF and the routine programme, 112 (1%) were diagnosed with multidrug-resistant TB. Conclusion: There was a substantial yield of TB cases among risk groups such as PLHIV and household contacts. Although the yield in urban slum dwellers was found to be moderate, some intervention should nonetheless be targeted because of the large population and poor access to care in this group. PMID:27358808

  10. Treatment of Active Pulmonary Tuberculosis in Adults: Current Standards and Recent Advances

    PubMed Central

    Hall, Ronald G.; Leff, Richard D.; Gumbo, Tawanda

    2010-01-01

    Tuberculosis is a global pandemic, with 9 million new cases of the disease and approximately 2 million deaths each year. More than 98% of patients treated for tuberculosis in the United States between 1993 and 2007 had drug-susceptible strains. The standard treatment regimen for drug-susceptible tuberculosis has not changed in decades and was developed on the basis of empiric observations of different treatment regimens. Only recently has the veracity of the scientific basis for standard therapy been examined. The backbone of therapy is still isoniazid, rifampin, and pyrazinamide, although fluoroquinolones are being investigated as a replacement for isoniazid. Recent population pharmacokinetic studies have demonstrated the importance of individualized dosing of isoniazid, pyrazinamide, and rifampin. Isoniazid serum clearance differs depending on the patient’s number of N-acetyltransferase 2 gene *4 (NAT2*4) alleles. Pyrazinamide serum clearance has been shown to increase with increases in body weight. Rifampin’s volume of distribution, clearance, and absorption have wide between-patient and within-patient variability. Microbial pharmacokinetic-pharmacodynamic (PK-PD) indexes and targets to optimize microbial killing and minimize resistance have been identified for rifampin, isoniazid, pyrazinamide, and the fluoroquinolones. These PK-PD indexes suggest that different doses and dosing schedules than those currently recommended could optimize therapy and perhaps shorten duration of therapy. Efflux pump inhibition is also being investigated to enhance first-line antituberculosis drug therapy. Comorbid conditions such as diabetes mellitus and genetically determined iron overload syndromes have been associated with significantly worse patient outcomes. Therapy for these and other patient groups needs further improvement. These patient factors, the covariates for pharmacokinetic variability, and PK-PD factors suggest the need to individualize therapy for patients with

  11. Optimization of Pyrrolamides as Mycobacterial GyrB ATPase Inhibitors: Structure-Activity Relationship and In Vivo Efficacy in a Mouse Model of Tuberculosis

    PubMed Central

    P, Shahul Hameed; Mukherjee, Kakoli; Nandi, Vrinda; Waterson, David; Shandil, Radha; Balganesh, Meenakshi; Sambandamurthy, Vasan K.; Raichurkar, Anand Kumar; Deshpande, Abhijeet; Ghosh, Anirban; Awasthy, Disha; Shanbhag, Gajanan; Sheikh, Gulebahar; McMiken, Helen; Puttur, Jayashree; Reddy, Jitendar; Werngren, Jim; Read, Jon; Kumar, Mahesh; R, Manjunatha; Chinnapattu, Murugan; Madhavapeddi, Prashanti; Manjrekar, Praveena; Basu, Reetobrata; Gaonkar, Sheshagiri; Sharma, Sreevalli; Hoffner, Sven; Humnabadkar, Vaishali; Subbulakshmi, Venkita; Panduga, Vijender

    2014-01-01

    Moxifloxacin has shown excellent activity against drug-sensitive as well as drug-resistant tuberculosis (TB), thus confirming DNA gyrase as a clinically validated target for discovering novel anti-TB agents. We have identified novel inhibitors in the pyrrolamide class which kill Mycobacterium tuberculosis through inhibition of ATPase activity catalyzed by the GyrB domain of DNA gyrase. A homology model of the M. tuberculosis H37Rv GyrB domain was used for deciphering the structure-activity relationship and binding interactions of inhibitors with mycobacterial GyrB enzyme. Proposed binding interactions were later confirmed through cocrystal structure studies with the Mycobacterium smegmatis GyrB ATPase domain. The most potent compound in this series inhibited supercoiling activity of DNA gyrase with a 50% inhibitory concentration (IC50) of <5 nM, an MIC of 0.03 μg/ml against M. tuberculosis H37Rv, and an MIC90 of <0.25 μg/ml against 99 drug-resistant clinical isolates of M. tuberculosis. The frequency of isolating spontaneous resistant mutants was ∼10−6 to 10−8, and the point mutation mapped to the M. tuberculosis GyrB domain (Ser208 Ala), thus confirming its mode of action. The best compound tested for in vivo efficacy in the mouse model showed a 1.1-log reduction in lung CFU in the acute model and a 0.7-log reduction in the chronic model. This class of GyrB inhibitors could be developed as novel anti-TB agents. PMID:24126580

  12. Differential expression of miRNAs and their relation to active tuberculosis.

    PubMed

    Xu, Zhihong; Zhou, Aiping; Ni, Jinjing; Zhang, Qiufen; Wang, Ying; Lu, Jie; Wu, Wenjuan; Karakousis, Petros C; Lu, Shuihua; Yao, Yufeng

    2015-07-01

    The aim of this work was to screen miRNA signatures dysregulated in tuberculosis to improve our understanding of the biological role of miRNAs involved in the disease. Datasets deposited in publically available databases from microarray studies on infectious diseases and malignancies were retrieved, screened, and subjected to further analysis. Effect sizes were combined using the inverse-variance model and between-study heterogeneity was evaluated by the random effects model. 35 miRNAs were differentially expressed (12 up-regulated, 23 down-regulated; p < 0.05) by combining 15 datasets of tuberculosis and other infectious diseases. 15 miRNAs were found to be significantly differentially regulated (7 up-regulated, 8 down-regulated; p < 0.05) by combining 53 datasets of tuberculosis and malignancies. Most of the miRNA signatures identified in this study were found to be involved in immune responses and metabolism. Expression of these miRNA signatures in serum samples from TB subjects (n = 11) as well as healthy controls (n = 10) was examined by TaqMan miRNA array. Taken together, the results revealed differential expression of miRNAs in TB, but available datasets are limited and these miRNA signatures should be validated in future studies.

  13. Type I IFN Inhibits Alternative Macrophage Activation during Mycobacterium tuberculosis Infection and Leads to Enhanced Protection in the Absence of IFN-γ Signaling

    PubMed Central

    Sousa, Jeremy; McNab, Finlay W.; Torrado, Egídio; Cardoso, Filipa; Machado, Henrique; Castro, Flávia; Cardoso, Vânia; Gaifem, Joana; Wu, Xuemei; Appelberg, Rui; Castro, António Gil; O’Garra, Anne; Saraiva, Margarida

    2016-01-01

    Tuberculosis causes ∼1.5 million deaths every year, thus remaining a leading cause of death from infectious diseases in the world. A growing body of evidence demonstrates that type I IFN plays a detrimental role in tuberculosis pathogenesis, likely by interfering with IFN-γ–dependent immunity. In this article, we reveal a novel mechanism by which type I IFN may confer protection against Mycobacterium tuberculosis infection in the absence of IFN-γ signaling. We show that production of type I IFN by M. tuberculosis–infected macrophages induced NO synthase 2 and inhibited arginase 1 gene expression. In vivo, absence of both type I and type II IFN receptors led to strikingly increased levels of arginase 1 gene expression and protein activity in infected lungs, characteristic of alternatively activated macrophages. This correlated with increased lung bacterial burden and pathology and decreased survival compared with mice deficient in either receptor. Increased expression of other genes associated with alternatively activated macrophages, as well as increased expression of Th2-associated cytokines and decreased TNF expression, were also observed. Thus, in the absence of IFN-γ signaling, type I IFN suppressed the switching of macrophages from a more protective classically activated phenotype to a more permissive alternatively activated phenotype. Together, our data support a model in which suppression of alternative macrophage activation by type I IFN during M. tuberculosis infection, in the absence of IFN-γ signaling, contributes to host protection. PMID:27849167

  14. Evaluation of prediagnosis emergency department presentations in patients with active tuberculosis: the role of chest radiography, risk factors and symptoms

    PubMed Central

    Appleton, S C; Connell, D W; Singanayagam, A; Bradley, P; Pan, D; Sanderson, F; Cleaver, B; Rahman, A; Kon, O M

    2017-01-01

    Introduction London has a high rate of tuberculosis (TB) with 2572 cases reported in 2014. Cases are more common in non-UK born, alcohol-dependent or homeless patients. The emergency department (ED) presents an opportunity for the diagnosis of TB in these patient groups. This is the first study describing the clinico-radiological characteristics of such attendances in two urban UK hospitals for pulmonary TB (PTB) and extrapulmonary TB (EPTB). Methods We conducted a retrospective cohort study using the London TB Register (LTBR) and hospital records to identify patients who presented to two London ED's in the 6 months prior to their ultimate TB diagnosis 2011–2012. Results 397 TB cases were identified. 39% (154/397) had presented to the ED in the 6 months prior to diagnosis. In the study population, the presence of cough, weight loss, fever and night sweats only had prevalence rates of 40%, 34%, 34% and 21%, respectively. Chest radiography was performed in 76% (117/154) of patients. For cases where a new diagnosis of TB was suspected, 73% (41/56) had an abnormal radiograph, compared with 36% (35/98) of patients where it was not. There was an abnormality on a chest radiograph in 73% (55/75) of PTB cases and also in 40% (21/52) of EPTB cases where a film was requested. Conclusions A large proportion of patients with TB present to ED. A diagnosis was more likely in the presence of an abnormal radiograph, suggesting opportunities for earlier diagnosis if risk factors, symptoms and chest radiograph findings are combined. PMID:28123749

  15. Evaluating the anti Mycobacterium tuberculosis activity of Alpinia galanga (L.) Willd. axenically under reducing oxygen conditions and in intracellular assays

    PubMed Central

    2014-01-01

    Background In tuberculosis (TB), the steadily increasing bacterial resistance to existing drugs and latent TB continue to be major concerns. A combination of conventional drugs and plant derived therapeutics can serve to expand the antimicrobial spectrum, prevent the emergence of drug resistant mutants and minimize toxicity. Alpinia galanga, used in various traditional medicines, possesses broad spectrum antibacterial properties. The study was undertaken to assess the antimycobacterial potential of A. galanga in axenic (under aerobic and anaerobic conditions) and intracellular assays. Methods Phytochemical analysis was done using HPTLC. The acetone, aqueous and ethanolic extracts (1, 10, 25, 50 and 100 μg/ml) of A. galanga were tested axenically using Microplate Alamar Blue Assay (MABA) against Mycobacterium tuberculosis (M.tb) H37Rv and three drug sensitive and three multi drug resistant clinical isolates. The activity of the extracts was also evaluated intracellularly in A549 cell line against these strains. The extracts active under intracellular conditions were further tested in an axenic setup under reducing oxygen concentrations using only H37Rv. Results 1´ acetoxychavicol acetate, the reference standard used, was present in all the three extracts. The acetone and ethanolic extracts were active in axenic (aerobic and anaerobic) and intracellular assays. The aqueous extract did not demonstrate activity under the defined assay parameters. Conclusion A. galanga exhibits anti M.tb activity with multiple modes of action. Since the activity of the extracts was observed under reducing oxygen concentrations, it may be effective in treating the dormant and non-replicating bacteria of latent TB. Though the hypothesis needs further testing, A. galanga being a regular dietary component may be utilized in combination with the conventional TB therapy for enhanced efficacy. PMID:24592852

  16. Identification of 2-Aminothiazole-4-Carboxylate Derivatives Active against Mycobacterium tuberculosis H37Rv and the β-Ketoacyl-ACP Synthase mtFabH

    PubMed Central

    Al-Balas, Qosay; Anthony, Nahoum G.; Al-Jaidi, Bilal; Alnimr, Amani; Abbott, Grainne; Brown, Alistair K.; Taylor, Rebecca C.; Besra, Gurdyal S.; McHugh, Timothy D.; Gillespie, Stephen H.; Johnston, Blair F.; Mackay, Simon P.; Coxon, Geoffrey D.

    2009-01-01

    Background Tuberculosis (TB) is a disease which kills two million people every year and infects approximately over one-third of the world's population. The difficulty in managing tuberculosis is the prolonged treatment duration, the emergence of drug resistance and co-infection with HIV/AIDS. Tuberculosis control requires new drugs that act at novel drug targets to help combat resistant forms of Mycobacterium tuberculosis and reduce treatment duration. Methodology/Principal Findings Our approach was to modify the naturally occurring and synthetically challenging antibiotic thiolactomycin (TLM) to the more tractable 2-aminothiazole-4-carboxylate scaffold to generate compounds that mimic TLM's novel mode of action. We report here the identification of a series of compounds possessing excellent activity against M. tuberculosis H37Rv and, dissociatively, against the β-ketoacyl synthase enzyme mtFabH which is targeted by TLM. Specifically, methyl 2-amino-5-benzylthiazole-4-carboxylate was found to inhibit M. tuberculosis H37Rv with an MIC of 0.06 µg/ml (240 nM), but showed no activity against mtFabH, whereas methyl 2-(2-bromoacetamido)-5-(3-chlorophenyl)thiazole-4-carboxylate inhibited mtFabH with an IC50 of 0.95±0.05 µg/ml (2.43±0.13 µM) but was not active against the whole cell organism. Conclusions/Significance These findings clearly identify the 2-aminothiazole-4-carboxylate scaffold as a promising new template towards the discovery of a new class of anti-tubercular agents. PMID:19440303

  17. FDG PET/CT findings of common bile duct tuberculosis.

    PubMed

    Dong, Aisheng; Wang, Yang; Gong, Jing; Zuo, Changjing

    2014-01-01

    Common bile duct (CBD) tuberculosis is rare. A 39-year-old woman was referred because of a 5-month history of abdominal pain. Abdominal enhanced MRI and CT showed dilatation of the distal CBD with irregularly thickened wall. Enhanced CT revealed enlarged retroperitoneal lymph nodes. FDG PET/CT showed increased FDG uptake of the CBD lesion and several retroperitoneal lymph nodes with slight FDG uptake. CBD cholangiocarcinoma with retroperitoneal lymph node metastasis was suspected. CBD tuberculosis was confirmed by endoluminal biopsy. Tuberculosis should be considered in the differential diagnosis of abnormal biliary FDG accumulation, particularly in tuberculosis endemic areas.

  18. Lateral flow urine lipoarabinomannan assay for detecting active tuberculosis in Hiv-positive adults

    PubMed Central

    Shah, Maunank; Hanrahan, Colleen; Wang, Zhuo Yu; Dendukuri, Nandini; Lawn, Stephen D; Denkinger, Claudia M; Steingart, Karen R

    2016-01-01

    Background Rapid detection of tuberculosis (TB) among people living with human immunodeficiency virus (HIV) is a global health priority. HIV-associated TB may have different clinical presentations and is challenging to diagnose. Conventional sputum tests have reduced sensitivity in HIV-positive individuals, who have higher rates of extrapulmonary TB compared with HIV-negative individuals. The lateral flow urine lipoarabinomannan assay (LF-LAM) is a new, commercially available point-of-care test that detects lipoarabinomannan (LAM), a lipopolysaccharide present in mycobacterial cell walls, in people with active TB disease. Objectives To assess the accuracy of LF-LAM for the diagnosis of active TB disease in HIV-positive adults who have signs and symptoms suggestive of TB (TB diagnosis).To assess the accuracy of LF-LAM as a screening test for active TB disease in HIV-positive adults irrespective of signs and symptoms suggestive of TB (TB screening). Search methods We searched the following databases without language restriction on 5 February 2015: the Cochrane Infectious Diseases Group Specialized Register; MEDLINE (PubMed,1966); EMBASE (OVID, from 1980); Science Citation Index Expanded (SCI-EXPANDED, from 1900), Conference Proceedings Citation Index-Science (CPCI-S, from 1900), and BIOSIS Previews (from 1926) (all three using the Web of Science platform; MEDION; LILACS (BIREME, from 1982); SCOPUS (from 1995); the metaRegister of Controlled Trials (mRCT); the search portal of the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP); and ProQuest Dissertations & Theses A&l (from 1861). Selection criteria Eligible study types included randomized controlled trials, cross-sectional studies, and cohort studies that determined LF-LAM accuracy for TB against a microbiological reference standard (culture or nucleic acid amplification test from any body site). A higher quality reference standard was one in which two or more specimen types were

  19. MCP-1 -2518 A/G functional polymorphism is associated with increased susceptibility to active pulmonary tuberculosis in Tunisian patients.

    PubMed

    Ben-Selma, Walid; Harizi, Hedi; Boukadida, Jalel

    2011-11-01

    Monocyte chemoattractant protein-1 (MCP-1) plays crucial role in protective immunity against Mycobacterium tuberculosis (MT). In this study, we examined whether single nucleotide polymorphism (SNP) -2518 A/G (rs 1024611) of MCP-1 affect the susceptibility to active tuberculosis (TB) in Tunisian populations. Genomic DNA from patients with active TB (168 cases of pulmonary TB and 55 cases of extrapulmonary TB) and ethnically controls (150 cases) was genotyped for the MCP-1 -2518 A/G SNP by polymerase chain reaction fragment length polymorphism (PCR-RFLP). We observed that -2518 G allele and GG genotype (high MCP-1 producer) frequencies were significantly more elevated in active pulmonary TB group in comparison to control group [34 vs. 22%; P = 0.0007; 15 vs. 5%, P corrected for the number of genotypes (Pc) = 0.015; respectively]. Additionally, they were associated with increased risk development of this clinical form of TB [odds ratio (OR) = 1.83, 95% confidence intervals (CI) = 1.26-2.66; OR = 3.1, 95% CI = 1.28-7.76; respectively]. However, wild type allele -2518 A and AA genotype were over-represented in control group (78 and 62%) and seem to be protective factors against TB. Moreover, -2518 AA genotype was more frequent in control group and was associated with resistance against development of active pulmonary TB (OR = 0.56, 95% CI = 0.35-0.89, Pc = 0.03). Our findings confirm the key role of -2518 A/G SNP of MCP-1 and support its association with resistance/susceptibility to the development of active pulmonary TB in the Tunisian population.

  20. A Bayesian Nonlinear Mixed-Effects Regression Model for the Characterization of Early Bactericidal Activity of Tuberculosis Drugs

    PubMed Central

    Burger, Divan Aristo; Schall, Robert

    2015-01-01

    Trials of the early bactericidal activity (EBA) of tuberculosis (TB) treatments assess the decline, during the first few days to weeks of treatment, in colony forming unit (CFU) count of Mycobacterium tuberculosis in the sputum of patients with smear-microscopy-positive pulmonary TB. Profiles over time of CFU data have conventionally been modeled using linear, bilinear, or bi-exponential regression. We propose a new biphasic nonlinear regression model for CFU data that comprises linear and bilinear regression models as special cases and is more flexible than bi-exponential regression models. A Bayesian nonlinear mixed-effects (NLME) regression model is fitted jointly to the data of all patients from a trial, and statistical inference about the mean EBA of TB treatments is based on the Bayesian NLME regression model. The posterior predictive distribution of relevant slope parameters of the Bayesian NLME regression model provides insight into the nature of the EBA of TB treatments; specifically, the posterior predictive distribution allows one to judge whether treatments are associated with monolinear or bilinear decline of log(CFU) count, and whether CFU count initially decreases fast, followed by a slower rate of decrease, or vice versa. PMID:25322214

  1. Validation of a homology model of Mycobacterium tuberculosis DXS: rationalization of observed activities of thiamine derivatives as potent inhibitors of two orthologues of DXS.

    PubMed

    Masini, T; Lacy, B; Monjas, L; Hawksley, D; de Voogd, A R; Illarionov, B; Iqbal, A; Leeper, F J; Fischer, M; Kontoyianni, M; Hirsch, A K H

    2015-12-14

    The enzyme DXS catalyzes the first, rate-limiting step of the 2-C-methyl-d-erythritol-4-phosphate (MEP, 1) pathway using thiamine diphosphate (ThDP) as cofactor; the DXS-catalyzed reaction constitutes also the first step in vitamin B1 and B6 metabolism in bacteria. DXS is the least studied among the enzymes of this pathway in terms of crystallographic information, with only one complete crystal structure deposited in the Protein Data Bank (Deinococcus radiodurans DXS, PDB: ). We synthesized a series of thiamine and ThDP derivatives and tested them for their biochemical activity against two DXS orthologues, namely D. radiodurans DXS and Mycobacterium tuberculosis DXS. These experimental results, combined with advanced docking studies, led to the development and validation of a homology model of M. tuberculosis DXS, which, in turn, will guide medicinal chemists in rationally designing potential inhibitors for M. tuberculosis DXS.

  2. Characterization of suspected illegal skin whitening cosmetics.

    PubMed

    Desmedt, B; Van Hoeck, E; Rogiers, V; Courselle, P; De Beer, J O; De Paepe, K; Deconinck, E

    2014-03-01

    An important group of suspected illegal cosmetics consists of skin bleaching products, which are usually applied to the skin of the face, hands and décolleté for local depigmentation of hyper pigmented regions or more importantly, for a generalized reduction of the skin tone. These cosmetic products are suspected to contain illegal active substances that may provoke as well local as systemic toxic effects, being the reason for their banning from the EU market. In that respect, illegal and restricted substances in cosmetics, known to have bleaching properties, are in particular hydroquinone, tretinoin and corticosteroids. From a legislative point of view, all cosmetic products containing a prohibited whitening agent are illegal and must be taken off the EU market. A newly developed screening method using ultra high performance liquid chromatography-time off flight-mass spectrometry allows routine analysis of suspected products. 163 suspected skin whitening cosmetics, collected by Belgian inspectors at high risk sites such as airports and so-called ethnic cosmetic shops, were analyzed and 59% were classified as illegal. The whitening agents mostly detected were clobetasol propionate and hydroquinone, which represent a serious health risk when repeatedly and abundantly applied to the skin.

  3. Indirect Estimates of Jaw Muscle Tension in Children with Suspected Hypertonia, Children with Suspected Hypotonia, and Matched Controls

    ERIC Educational Resources Information Center

    Connaghan, Kathryn P.; Moore, Christopher A.

    2013-01-01

    Purpose: In this study, the authors compared indirect estimates of jaw-muscle tension in children with suspected muscle-tone abnormalities with age- and gender-matched controls. Method: Jaw movement and muscle activation were measured in children (ages 3 years, 11 months, to 10 years) with suspected muscle-tone abnormalities (Down syndrome or…

  4. Esters of Pyrazinoic Acid Are Active against Pyrazinamide-Resistant Strains of Mycobacterium tuberculosis and Other Naturally Resistant Mycobacteria In Vitro and Ex Vivo within Macrophages.

    PubMed

    Pires, David; Valente, Emília; Simões, Marta Filipa; Carmo, Nuno; Testa, Bernard; Constantino, Luís; Anes, Elsa

    2015-12-01

    Pyrazinamide (PZA) is active against major Mycobacterium tuberculosis species (M. tuberculosis, M. africanum, and M. microti) but not against M. bovis and M. avium. The latter two are mycobacterial species involved in human and cattle tuberculosis and in HIV coinfections, respectively. PZA is a first-line agent for the treatment of human tuberculosis and requires activation by a mycobacterial pyrazinamidase to form the active metabolite pyrazinoic acid (POA). As a result of this mechanism, resistance to PZA, as is often found in tuberculosis patients, is caused by point mutations in pyrazinamidase. In previous work, we have shown that POA esters and amides synthesized in our laboratory were stable in plasma (M. F. Simões, E. Valente, M. J. Gómez, E. Anes, and L. Constantino, Eur J Pharm Sci 37:257-263, 2009, http://dx.doi.org/10.1016/j.ejps.2009.02.012). Although the amides did not present significant activity, the esters were active against sensitive mycobacteria at concentrations 5- to 10-fold lower than those of PZA. Here, we report that these POA derivatives possess antibacterial efficacy in vitro and ex vivo against several species and strains of Mycobacterium with natural or acquired resistance to PZA, including M. bovis and M. avium. Our results indicate that the resistance probably was overcome by cleavage of the prodrugs into POA and a long-chain alcohol. Although it is not possible to rule out that the esters have intrinsic activity per se, we bring evidence here that long-chain fatty alcohols possess a significant antimycobacterial effect against PZA-resistant species and strains and are not mere inactive promoieties. These findings may lead to candidate dual drugs having enhanced activity against both PZA-susceptible and PZA-resistant isolates and being suitable for clinical development.

  5. Esters of Pyrazinoic Acid Are Active against Pyrazinamide-Resistant Strains of Mycobacterium tuberculosis and Other Naturally Resistant Mycobacteria In Vitro and Ex Vivo within Macrophages

    PubMed Central

    Valente, Emília; Simões, Marta Filipa; Carmo, Nuno; Testa, Bernard

    2015-01-01

    Pyrazinamide (PZA) is active against major Mycobacterium tuberculosis species (M. tuberculosis, M. africanum, and M. microti) but not against M. bovis and M. avium. The latter two are mycobacterial species involved in human and cattle tuberculosis and in HIV coinfections, respectively. PZA is a first-line agent for the treatment of human tuberculosis and requires activation by a mycobacterial pyrazinamidase to form the active metabolite pyrazinoic acid (POA). As a result of this mechanism, resistance to PZA, as is often found in tuberculosis patients, is caused by point mutations in pyrazinamidase. In previous work, we have shown that POA esters and amides synthesized in our laboratory were stable in plasma (M. F. Simões, E. Valente, M. J. Gómez, E. Anes, and L. Constantino, Eur J Pharm Sci 37:257–263, 2009, http://dx.doi.org/10.1016/j.ejps.2009.02.012). Although the amides did not present significant activity, the esters were active against sensitive mycobacteria at concentrations 5- to 10-fold lower than those of PZA. Here, we report that these POA derivatives possess antibacterial efficacy in vitro and ex vivo against several species and strains of Mycobacterium with natural or acquired resistance to PZA, including M. bovis and M. avium. Our results indicate that the resistance probably was overcome by cleavage of the prodrugs into POA and a long-chain alcohol. Although it is not possible to rule out that the esters have intrinsic activity per se, we bring evidence here that long-chain fatty alcohols possess a significant antimycobacterial effect against PZA-resistant species and strains and are not mere inactive promoieties. These findings may lead to candidate dual drugs having enhanced activity against both PZA-susceptible and PZA-resistant isolates and being suitable for clinical development. PMID:26438493

  6. An Unusual Suspect

    ERIC Educational Resources Information Center

    Lum, Lydia

    2007-01-01

    In this article, the author discusses the work of Dr. Grace Lee Boggs. It begins with a history of her childhood and education, then provides an account of Boggs's awakening to the cause of Black liberation, the history of her work within the movement, and her current activities. Throughout the article, other scholars discuss their deep…

  7. Relationship between Pyrazinamide Resistance, Loss of Pyrazinamidase Activity, and Mutations in the pncA Locus in Multidrug-Resistant Clinical Isolates of Mycobacterium tuberculosis

    PubMed Central

    Mestdagh, M.; Fonteyne, P. A.; Realini, L.; Rossau, R.; Jannes, G.; Mijs, W.; De Smet, K. A. L.; Portaels, F.; Van den Eeckhout, E.

    1999-01-01

    Sixty-two Mycobacterium tuberculosis isolates were tested for pyrazinamidase activity, and their pyrazinamide susceptibility was determined by the radiometric method. Sequencing of pncA genes in the 23 resistant strains revealed mutations in 16 pyrazinamidase-negative strains, 11 of which had not been previously described. Six isolates containing wild-type pncA might possess alternative resistance mechanisms. PMID:10471589

  8. Interferon gamma +874T/A polymorphism is associated with susceptibility to active pulmonary tuberculosis development in Tunisian patients.

    PubMed

    Ben Selma, Walid; Harizi, Hedi; Bougmiza, Iheb; Hannachi, Naila; Ben Kahla, Imen; Zaieni, Radhia; Boukadida, Jalel

    2011-06-01

    Interferon gamma (IFN-γ) is a key cytokine involved mainly in the defense against intracellular pathogens such as Mycobacterium tuberculosis. Given its key role in the control of tuberculosis (TB), in the present article we have investigated a possible association between IFN-γ gene single-nucleotide polymorphism linked to high and low producer phenotypes (IFN-γ [+874T(high) → A(low)]) (rs2430561) and risk development of active TB in Tunisian patients. Genomic DNA samples were obtained from 223 patients with active TB (168 pulmonary and 55 extrapulmonary cases) and 150 healthy blood donors. Genotypes were analyzed using polymerase chain reaction-restriction fragment length polymorphism method. The +874 AA genotype (low IFN-γ producer) was significantly associated with increased risk of developing of active pulmonary TB (odds ratio [OR] = 2.18; 95% confidence intervals [CI], 1.33-3.57; P corrected for the number of genotypes [Pc] = 0.003). By contrast, the AT genotype was found to be significantly associated with resistance to pulmonary TB (OR = 0.46; 95% CI, 0.28-0.74; Pc = 0.0018) and extrapulmonary TB development (OR = 0.46; 95% CI, 0.23-0.91; Pc = 0.045). Collectively, our data showed that the IFN-γ +874T/A polymorphism is a determinant in the resistance or susceptibility to the development of active TB in the studied population.

  9. Mycobacterial Protein Tyrosine Phosphatases A and B Inhibitors Augment the Bactericidal Activity of the Standard Anti-tuberculosis Regimen

    PubMed Central

    Dutta, Noton K.; He, Rongjun; Pinn, Michael L.; He, Yantao; Burrows, Francis; Zhang, Zhong-Yin; Karakousis, Petros C.

    2016-01-01

    Novel drugs are required to shorten the duration of treatment for tuberculosis (TB) and to combat the emergence of drug resistance. One approach has been to identify and target Mycobacterium tuberculosis (Mtb) virulence factors, which promote the establishment of TB infection and pathogenesis. Mtb produces a number of virulence factors, including two protein tyrosine phosphatases (PTPs), mPTPA and mPTPB, to evade the antimicrobial functions of host macrophages. To assess the therapeutic potential of targeting the virulent Mtb PTPs, we developed highly potent and selective inhibitors of mPTPA (L335-M34) and mPTPB (L01-Z08) with drug-like properties. We tested the bactericidal activity of L335-M34 and L01-Z08 alone or together in combination with the standard antitubercular regimen of isoniazid-rifampicin-pyrazinamide (HRZ) in the guinea pig model of chronic TB infection, which faithfully recapitulates some of the key histological features of human TB lesions. Following a single dose of L335-M34 50mg/kg and L01-Z08 20 mg/kg, plasma levels were maintained at levels 10-fold greater than the biochemical IC50 for 12–24 hours. Although neither PTP inhibitor alone significantly enhanced the antibacterial activity of HRZ, dual inhibition of mPTPA and mPTPB in combination with HRZ showed modest synergy, even after 2 weeks of treatment. After 6 weeks of treatment, the degree of lung inflammation correlated with the bactericidal activity of each drug regimen. This study highlights the potential utility of targeting Mtb virulence factors, and specifically the Mtb PTPs, as a strategy for enhancing the activity of standard anti-TB treatment. PMID:27478867

  10. Antigen smuggling in tuberculosis.

    PubMed

    Hudrisier, Denis; Neyrolles, Olivier

    2014-06-11

    The importance of CD4 T lymphocytes in immunity to M. tuberculosis is well established; however, how dendritic cells activate T cells in vivo remains obscure. In this issue of Cell Host & Microbe, Srivastava and Ernst (2014) report a mechanism of antigen transfer for efficient activation of antimycobacterial T cells.

  11. Tuberculosis (TB): Treatment

    MedlinePlus

    ... Training Home Conditions Tuberculosis (TB) Treating Tuberculosis Treating Tuberculosis Make an Appointment Refer a Patient Ask a ... bones is treated longer. NEXT: Preventive Treatment Diagnosing Tuberculosis History of TB Clinical Trials For more than ...

  12. The increased risk of active tuberculosis disease in patients with dermatomyositis – a nationwide retrospective cohort study

    PubMed Central

    Wu, Ping-Hsun; Lin, Yi-Ting; Yang, Yi-Hsin; Lin, Yu-Chih; Lin, Yi-Ching

    2015-01-01

    The risk of active tuberculosis (TB) in patients with dermatomyositis (DM) is poorly understood. The cohort study aimed to investigate the association between DM and the risk of active TB disease. We conducted a population based study on 4,958 patients with newly diagnosed DM and 19,832 matched controls according to age, sex, and index date between 1998 and 2008. The hazard ratios (HRs) and cumulative incidences of active TB disease between DM patients and controls were analyzed. During the study period, a total of 85 (1.7%) DM patients developed active TB disease, which was significantly higher than that of non-DM patients (0.64%). The incidence rate of active TB disease was higher among DM patients than controls (incidence rate ratio 2.95; 95% confidence interval [CI], 2.24 to 3.88). The Cox regression model demonstrated significantly higher active TB disease rate among DM patients compared with controls (adjusted HR, 2.64; 95% CI, 1.97 to 3.54; p < 0.001) after adjusting for age, sex, and underlying medical disorders. The most significant risk factors for developing active TB included male sex, diabetes mellitus comorbidity, and use of corticosteroids and azathioprine in DM patients. In conclusion, DM patients are at a greater risk for active TB disease. PMID:26573418

  13. Targeting phenotypically tolerant Mycobacterium tuberculosis

    PubMed Central

    Gold, Ben; Nathan, Carl

    2016-01-01

    While the immune system is credited with averting tuberculosis in billions of individuals exposed to Mycobacterium tuberculosis, the immune system is also culpable for tempering the ability of antibiotics to deliver swift and durable cure of disease. In individuals afflicted with tuberculosis, host immunity produces diverse microenvironmental niches that support suboptimal growth, or complete growth arrest, of M. tuberculosis. The physiological state of nonreplication in bacteria is associated with phenotypic drug tolerance. Many of these host microenvironments, when modeled in vitro by carbon starvation, complete nutrient starvation, stationary phase, acidic pH, reactive nitrogen intermediates, hypoxia, biofilms, and withholding streptomycin from the streptomycin-addicted strain SS18b, render M. tuberculosis profoundly tolerant to many of the antibiotics that are given to tuberculosis patients in a clinical setting. Targeting nonreplicating persisters is anticipated to reduce the duration of antibiotic treatment and rate of post-treatment relapse. Some promising drugs to treat tuberculosis, such as rifampicin and bedaquiline, only kill nonreplicating M. tuberculosis in vitro at concentrations far greater than their minimal inhibitory concentrations against replicating bacilli. There is an urgent demand to identify which of the currently used antibiotics, and which of the molecules in academic and corporate screening collections, have potent bactericidal action on nonreplicating M. tuberculosis. With this goal, we review methods of high throughput screening to target nonreplicating M. tuberculosis and methods to progress candidate molecules. A classification based on structures and putative targets of molecules that have been reported to kill nonreplicating M. tuberculosis revealed a rich diversity in pharmacophores. However, few of these compounds were tested under conditions that would exclude the impact of adsorbed compound acting during the recovery phase of

  14. Use of the QuantiFERON-TB Gold In-Tube Test in the Diagnosis and Monitoring of Treatment Efficacy in Active Pulmonary Tuberculosis

    PubMed Central

    Chang, Ping-Chin; Wang, Pin-Hui; Chen, Kow-Tong

    2017-01-01

    The value of QuantiFERON in the diagnosis of tuberculosis disease and in the monitoring of the response to anti-tuberculosis treatment is unclear. The aims of this study were to evaluate the accuracy of the QuantiFERON-TB Gold In-Tube (QFT-GIT) test in the diagnosis of tuberculosis and in the monitoring of the response to anti-tuberculosis treatment in patients with active pulmonary tuberculosis (PTB). Between January 2013 and December 2015, 133 cases with active PTB and 133 controls with no mycobacterial infection, matched by age (within 3 years) and by the week that they visited Tainan Chest Hospital, were enrolled in the study. Serial testing by QFT-GIT at baseline and after 2 and 6 months of treatment was performed. At these time points, a comparison of the performance of QFT-GIT with that of sputum culture status among study subjects was conducted. Compared to baseline, 116 (87.2%) cases showed a decreased response, whereas 17 (12.8%) showed persistent or stronger interferon-gamma (IFN-γ) responses at 2 months. PTB patients IFN-γ responses declined significantly from baseline to 2 months (median, 6.32 vs. 4.12; p < 0.005). The sensitivity values of the QFT-GIT test for the detection of pulmonary tuberculosis at cut-off points of 0.35 IU/mL, 0.20 IU/mL, and 0.10 IU/mL were 74.4%, 78.2%, and 80.5%, respectively. The specificity values at cut-off points of 0.35 IU/mL, 0.20 IU/mL, and 0.10 IU/mL were 66.2%, 63.9%, and 57.1%, respectively. Our results support the QFT-GIT assay as a potential tool for diagnosing tuberculosis and for monitoring the efficacy of anti-tuberculosis treatment. PMID:28264462

  15. Modulation of pro- and anti-inflammatory cytokines in active and latent tuberculosis by coexistent Strongyloides stercoralis infection.

    PubMed

    George, Parakkal Jovvian; Pavan Kumar, Nathella; Jaganathan, Jeeva; Dolla, Chandrakumar; Kumaran, Paul; Nair, Dina; Banurekha, Vaithilingam V; Shen, Kui; Nutman, Thomas B; Babu, Subash

    2015-12-01

    Helminth infections are known to induce modulation of both innate and adaptive immune responses in active and latent tuberculosis (TB). However, the role of helminth infections in modulating systemic cytokine responses in active and latent tuberculosis (LTB) is not known. To define the systemic cytokine levels in helminth-TB coinfection, we measured the circulating plasma levels of Type 1, Type 2, Type 17, other pro-inflammatory and regulatory cytokines in individuals with active TB (ATB) with or without coexistent Strongyloides stercoralis (Ss) infection by multiplex ELISA. Similarly, we also measured the same cytokine levels in individuals with LTB with or without concomitant Ss infection in a cross-sectional study. Our data reveal that individuals with ATB or LTB and coexistent Ss infection have significantly lower levels of Type 1 (IFNγ, TNFα and IL-2) and Type 17 (IL-17A and IL-17F) cytokines compared to those without Ss infection. In contrast, those with ATB and LTB with Ss infection have significantly higher levels of the regulatory cytokines (IL-10 and TGFβ), and those with LTB and Ss infection also have significantly higher levels of Type 2 cytokines (IL-4, IL-5 and IL-13) as well. Finally, those with LTB (but not ATB) exhibit significantly lower levels of other pro-inflammatory cytokines (IFNα, IFNβ, IL-6, IL-12 and GM-CSF). Our data therefore reveal a profound effect of Ss infection on the systemic cytokine responses in ATB and LTB and indicate that coincident helminth infections might influence pathogenesis of TB infection and disease.

  16. ATP-dependent motor activity of the transcription termination factor Rho from Mycobacterium tuberculosis

    PubMed Central

    D'Heygère, François; Schwartz, Annie; Coste, Franck; Castaing, Bertrand; Boudvillain, Marc

    2015-01-01

    The bacterial transcription termination factor Rho—a ring-shaped molecular motor displaying directional, ATP-dependent RNA helicase/translocase activity—is an interesting therapeutic target. Recently, Rho from Mycobacterium tuberculosis (MtbRho) has been proposed to operate by a mechanism uncoupled from molecular motor action, suggesting that the manner used by Rho to dissociate transcriptional complexes is not conserved throughout the bacterial kingdom. Here, however, we demonstrate that MtbRho is a bona fide molecular motor and directional helicase which requires a catalytic site competent for ATP hydrolysis to disrupt RNA duplexes or transcription elongation complexes. Moreover, we show that idiosyncratic features of the MtbRho enzyme are conferred by a large, hydrophilic insertion in its N-terminal ‘RNA binding’ domain and by a non-canonical R-loop residue in its C-terminal ‘motor’ domain. We also show that the ‘motor’ domain of MtbRho has a low apparent affinity for the Rho inhibitor bicyclomycin, thereby contributing to explain why M. tuberculosis is resistant to this drug. Overall, our findings support that, in spite of adjustments of the Rho motor to specific traits of its hosting bacterium, the basic principles of Rho action are conserved across species and could thus constitute pertinent screening criteria in high-throughput searches of new Rho inhibitors. PMID:25999346

  17. Evaluation of the Antibody in Lymphocyte Supernatant Assay to Detect Active Tuberculosis

    PubMed Central

    Sariko, Margaretha; Anderson, Caitlin; Mujaga, Buliga S.; Gratz, Jean; Mpagama, Stellah G.; Heysell, Scott; Kibiki, Gibson; Mmbaga, Blandina; Houpt, Eric

    2017-01-01

    Background We aimed to evaluate the antibody in lymphocyte supernatant (ALS) assay as a biomarker to diagnose tuberculosis among adults from Tanzania with and without HIV. Methods Adults admitted with suspicion for tuberculosis had sputa obtained for GeneXpert MTB/RIF, acid-fast bacilli smear and mycobacterial culture; blood was obtained prior to treatment initiation and after 4 weeks. Adults hospitalized with non-infectious conditions served as controls. Peripheral blood mononuclear cells were cultured unstimulated for 72 hours. Anti-mycobacterial antibodies were measured from culture supernatants by ELISA, using BCG vaccine as the coating antigen. Median ALS responses were compared between cases and controls at baseline and between cases over time. Results Of 97 TB cases, 85 were microbiologically confirmed and 12 were clinically diagnosed. Median ALS responses from TB cases (0.366 OD from confirmed cases and 0.285 from clinical cases) were higher compared to controls (0.085, p<0.001). ALS responses did not differ based on HIV status, CD4 count or sputum smear status. Over time, the median ALS values declined significantly (0.357 at baseline; 0.198 after 4-weeks, p<0.001). Conclusions Robust ALS responses were mounted by patients with TB regardless of HIV status, CD4 count, or low sputum bacillary burden, potentially conferring a unique niche for this immunologic biomarker for TB. PMID:28085899

  18. Spectrum of tuberculosis in patients with HIV infection in British Columbia: report of 40 cases.

    PubMed Central

    Korzeniewska-Kosela, M; FitzGerald, J M; Vedal, S; Allen, E A; Schechter, M T; Lawson, L; Phillips, P; Black, W; Montaner, J S

    1992-01-01

    OBJECTIVE: To review the clinical features, treatment and outcome of all known cases of tuberculosis in patients with human immunodeficiency virus (HIV) infection in British Columbia between 1984 and 1990. DESIGN: Retrospective case review. SETTING: Provincial tuberculosis registry and university-affiliated HIV clinic. PATIENTS: All people with HIV infection in whom active tuberculosis was diagnosed during the study period. RESULTS: All 40 patients identified were men; their mean age was 38 years. Of the subjects 30 (75%) were homosexual, 6 (15%) were homosexual and used intravenous drugs, 2 (5%) just used intravenous drugs, and 1 (2%) had had heterosexual contact with prostitutes; for the remaining subject the risk factor for HIV infection was not established. In all cases cultures of specimens from 15 body sources yielded Mycobacterium tuberculosis. Thirty-five of the patients had acquired immunodeficiency syndrome (AIDS), and five had HIV infection uncomplicated except for tuberculosis. In 28 (70%) of the cases no AIDS-defining disease had previously been diagnosed, and in 23 (58%) extrapulmonary tuberculosis represented the AIDS-defining disease. Symptoms at presentation included weight loss (in 80% of the cases), fever (in 75%), cough (in 70%) and night sweats (in 55%). The mean CD4 lymphocyte count was 0.2 x 10(9)/L (in 15 cases). Tuberculin skin test results were positive in 8 of 16 cases. The most striking radiologic finding was intrathoracic adenopathy. All except one of the 36 patients who received appropriate treatment responded favourably at first. Adverse reactions necessitating changes in treatment occurred in 12 (33%) of the cases. Relapse occurred after completion of therapy in two cases (one at 3 weeks and the other at 9 months after treatment was stopped). Tuberculosis was the cause of death in five cases. CONCLUSIONS: Tuberculosis in people with HIV infection commonly presents as extrapulmonary disease and precedes or coincides with other AIDS

  19. Controlling the seedbeds of tuberculosis: diagnosis and treatment of tuberculosis infection.

    PubMed

    Rangaka, Molebogeng X; Cavalcante, Solange C; Marais, Ben J; Thim, Sok; Martinson, Neil A; Swaminathan, Soumya; Chaisson, Richard E

    2015-12-05

    The billions of people with latent tuberculosis infection serve as the seedbeds for future cases of active tuberculosis. Virtually all episodes of tuberculosis disease are preceded by a period of asymptomatic Mycobacterium tuberculosis infection; therefore, identifying infected individuals most likely to progress to disease and treating such subclinical infections to prevent future disease provides a crucial opportunity to interrupt tuberculosis transmission and reduce the global burden of tuberculosis disease. Programmes focusing on single strategies rather than comprehensive programmes that deliver an integrated arsenal for tuberculosis control might continue to struggle. Tuberculosis preventive therapy is a poorly used method that is essential for controlling the reservoirs of disease that drive the epidemic. Comprehensive control strategies that combine preventive therapy for the most high-risk populations and communities with improved case-finding and treatment, control of transmission, and health systems strengthening could ultimately lead to worldwide tuberculosis elimination. In this Series paper we outline challenges to implementation of preventive therapy and provide pragmatic suggestions for overcoming them. We further advocate for tuberculosis preventive therapy as the core of a renewed worldwide focus to implement a comprehensive epidemic control strategy that would reduce new tuberculosis cases to elimination targets. This strategy would be underpinned by accelerated research to further understand the biology of subclinical tuberculosis infections, develop novel diagnostics and drug regimens specifically for subclinical tuberculosis infection, strengthen health systems and community engagement, and enhance sustainable large scale implementation of preventive therapy programmes.

  20. Characterization of regulatory T cells identified as CD4+CD25highCD39+ in patients with active tuberculosis

    PubMed Central

    Chiacchio, T; Casetti, R; Butera, O; Vanini, V; Carrara, S; Girardi, E; Di Mitri, D; Battistini, L; Martini, F; Borsellino, G; Goletti, D

    2009-01-01

    Forkhead box P3 (FoxP3) is a transcription factor whose expression characterizes regulatory T cells (Treg), but it is also present on activated T cells, thus hindering correct Treg identification. Using classical markers for Treg recognition, discordant results were found in terms of Treg expansion during active tuberculosis (TB) disease. Recently CD39 has been shown to be an accurate marker for Treg detection. The objectives of this study were: (i) to identify Treg expressing CD39 in patients with TB and to compare the results with those obtained by the standard phenotypic markers; (ii) to evaluate if Treg are expanded in vitro by exogenous interleukin (IL)-2 or by antigen-specific stimulation; and (iii) to characterize Treg function on the modulation of antigen-specific responses. We enrolled 13 patients with pulmonary TB and 12 healthy controls. Treg were evaluated by flow cytometry ex vivo and after antigen-specific in vitro stimulation using CD25, FoxP3, CD127 and CD39 markers. Results indicate that CD39+ cells within the CD4+CD25high cells have Treg properties (absence of interferon-γ production and transforming growth factor-β1 release upon stimulation). Ex vivo analysis did not show significant differences between TB patients and controls of Treg by classical or novel markers. In contrast, a significantly higher percentage of Treg was found in TB patients after antigen-specific stimulation both in the presence or absence of IL-2. Depletion of CD39+ Treg increased RD1-specific responses significantly. In conclusion, CD39 is an appropriate marker for Treg identification in TB. These results can be useful for future studies to monitor Mycobacterium tuberculosis-specific response during TB. PMID:19438599

  1. ATPase activity of Mycobacterium tuberculosis SecA1 and SecA2 proteins and its importance for SecA2 function in macrophages.

    PubMed

    Hou, Jie M; D'Lima, Nadia G; Rigel, Nathan W; Gibbons, Henry S; McCann, Jessica R; Braunstein, Miriam; Teschke, Carolyn M

    2008-07-01

    The Sec-dependent translocation pathway that involves the essential SecA protein and the membrane-bound SecYEG translocon is used to export many proteins across the cytoplasmic membrane. Recently, several pathogenic bacteria, including Mycobacterium tuberculosis, were shown to possess two SecA homologs, SecA1 and SecA2. SecA1 is essential for general protein export. SecA2 is specific for a subset of exported proteins and is important for M. tuberculosis virulence. The enzymatic activities of two SecA proteins from the same microorganism have not been defined for any bacteria. Here, M. tuberculosis SecA1 and SecA2 are shown to bind ATP with high affinity, though the affinity of SecA1 for ATP is weaker than that of SecA2 or Escherichia coli SecA. Amino acid substitution of arginine or alanine for the conserved lysine in the Walker A motif of SecA2 eliminated ATP binding. We used the SecA2(K115R) variant to show that ATP binding was necessary for the SecA2 function of promoting intracellular growth of M. tuberculosis in macrophages. These results are the first to show the importance of ATPase activity in the function of accessory SecA2 proteins.

  2. [Tuberculosis in infants less than 3 months of age].

    PubMed

    Del Rosal Rabes, Teresa; Baquero-Artigao, Fernando; Méndez-Echevarría, Ana María; Mellado Peña, María José

    2015-04-29

    A review was conducted on infants less than 3 months of age diagnosed with tuberculosis between 1978 and 2014. Eight patients were diagnosed (1.4% of paediatric tuberculosis cases): 3 confirmed congenital tuberculosis, 3 suspected (endometrial biopsy was not performed), and 2 postnatal tuberculosis. Tuberculin skin test was negative in two patients. Diagnostic performance of culture (7/7, 100%) and PCR (3/3, 100%) of gastric aspirates was higher than that of acid-fast bacilli smears (5/8, 62%) and IGRA test (1/3, 33%). Three patients developed miliary disease, and one died. In conclusion, tuberculosis in this age group is rare, severe, and difficult to diagnose. In cases lacking known postnatal contacts, maternal genital tuberculosis should be ruled out by endometrial biopsy.

  3. Structural analysis of the dodecameric proteasome activator PafE in Mycobacterium tuberculosis

    SciTech Connect

    Bai, Lin; Hu, Kuan; Wang, Tong; Jastrab, Jordan B.; Darwin, K. Heran; Li, Huilin

    2016-03-21

    Here, the human pathogen Mycobacterium tuberculosis (Mtb) requires a proteasome system to cause lethal infections in mice. We recently found that proteasome accessory factor E (PafE, Rv3780) activates proteolysis by the Mtb proteasome independently of adenosine triphosphate (ATP). Moreover, PafE contributes to the heat-shock response and virulence of Mtb. Here, we show that PafE subunits formed four-helix bundles similar to those of the eukaryotic ATP-independent proteasome activator subunits of PA26 and PA28. However, unlike any other known proteasome activator, PafE formed dodecamers with 12-fold symmetry, which required a glycine-XXX-glycine-XXX-glycine motif that is not found in previously described activators. Intriguingly, the truncation of the PafE carboxyl-terminus resulted in the robust binding of PafE rings to native proteasome core particles and substantially increased proteasomal activity, suggesting that the extended carboxyl-terminus of this cofactor confers suboptimal binding to the proteasome core particle. Collectively, our data show that proteasomal activation is not limited to hexameric ATPases in bacteria.

  4. [Extrapulmonary tuberculosis].

    PubMed

    Ketata, W; Rekik, W K; Ayadi, H; Kammoun, S

    2015-01-01

    Each year, there are more than eight million new cases of tuberculosis and 1.3 million deaths. There is a renewed interest in extrapulmonary forms of tuberculosis as its relative frequency increases. Among extrapulmonary organs, pleura and lymph nodes are the most common. Their diagnosis is often difficult and is based on clinical, radiological, bacteriological and histological findings. Extrapulmonary lesions are paucibacillary and samplings, in most cases, difficult to obtain, so diagnosis is often simply presumptive. Nucleic acid amplification tests, which are fast and specific, have greatly facilitated the diagnosis of some forms of extrapulmonary tuberculosis. However, their sensitivity is poor and a negative test does not eliminate the diagnosis. Treatment is the same as for pulmonary forms, but its duration is nine to 12 months for central nervous system and for bone tuberculosis. Corticosteroids are indicated in meningeal and pericardial localizations. Complementary surgery is used for certain complicated forms.

  5. Interaction of N-methyl-2-alkenyl-4-quinolones with ATP-dependent MurE ligase of Mycobacterium tuberculosis: antibacterial activity, molecular docking and inhibition kinetics

    PubMed Central

    Guzman, Juan David; Wube, Abraham; Evangelopoulos, Dimitrios; Gupta, Antima; Hüfner, Antje; Basavannacharya, Chandrakala; Rahman, Md. Mukhleshur; Thomaschitz, Christina; Bauer, Rudolf; McHugh, Timothy Daniel; Nobeli, Irene; Prieto, Jose M.; Gibbons, Simon; Bucar, Franz; Bhakta, Sanjib

    2011-01-01

    Objectives The aim of this study was to comprehensively evaluate the antibacterial activity and MurE inhibition of a set of N-methyl-2-alkenyl-4-quinolones found to inhibit the growth of fast-growing mycobacteria. Methods Using the spot culture growth inhibition assay, MICs were determined for Mycobacterium tuberculosis H37Rv, Mycobacterium bovis BCG and Mycobacterium smegmatis mc2155. MICs were determined for Mycobacterium fortuitum, Mycobacterium phlei, methicillin-resistant Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa using microplate dilution assays. Inhibition of M. tuberculosis MurE ligase activity was determined both by colorimetric and HPLC methods. Computational modelling and binding prediction of the quinolones in the MurE structure was performed using Glide. Kinetic experiments were conducted for understanding possible competitive relations of the quinolones with the endogenous substrates of MurE ligase. Results The novel synthetic N-methyl-2-alkenyl-4-quinolones were found to be growth inhibitors of M. tuberculosis and rapid-growing mycobacteria as well as methicillin-resistant S. aureus, while showing no inhibition for E. coli and P. aeruginosa. The quinolones were found to be inhibitory to MurE ligase of M. tuberculosis in the micromolar range (IC50 ∼40–200 μM) when assayed either spectroscopically or by HPLC. Computational docking of the quinolones on the published M. tuberculosis MurE crystal structure suggested that the uracil recognition site is a probable binding site for the quinolones. Conclusions N-methyl-2-alkenyl-4-quinolones are inhibitors of mycobacterial and staphylococcal growth, and show MurE ligase inhibition. Therefore, they are considered as a starting point for the development of increased affinity MurE activity disruptors. PMID:21622974

  6. Differential expression of antimicrobial peptides in active and latent tuberculosis and its relationship with diabetes mellitus.

    PubMed

    Gonzalez-Curiel, Irma; Castañeda-Delgado, Julio; Lopez-Lopez, Nallely; Araujo, Zaida; Hernandez-Pando, Rogelio; Gandara-Jasso, Benjamin; Macias-Segura, Noe; Enciso-Moreno, Antonio; Rivas-Santiago, Bruno

    2011-08-01

    Tuberculosis (TB) is one of the most important infectious diseases, causing 1.8 million deaths annually worldwide. This problem has increased because of the association with human immmunodeficiency virus and diabetes mellitus type 2, mainly in developing countries. In the past few years it has been highlighted the significance of antimicrobial peptides in the immunopathogenesis of TB ex vivo and in experimental models studies. In this study we analyzed the expression of CAMP, DEFA1, DEFB4, and DEFB103A in patients with latent TB and progressive TB with and without comorbidity with diabetes mellitus type 2. Antimicrobial peptide gene expression increased during progressive TB, which could be used as a biomarker for reactivation. By contrast, patients with diabetes mellitus type 2 have lower antimicrobial peptides gene expression, suggesting that the lack of its proper production in these patients contribute to enhance the risk for TB reactivation.

  7. Mycobacterium tuberculosis Differentially Activates cGAS- and Inflammasome-Dependent Intracellular Immune Responses through ESX-1.

    PubMed

    Wassermann, Ruth; Gulen, Muhammet F; Sala, Claudia; Perin, Sonia Garcia; Lou, Ye; Rybniker, Jan; Schmid-Burgk, Jonathan L; Schmidt, Tobias; Hornung, Veit; Cole, Stewart T; Ablasser, Andrea

    2015-06-10

    Cytosolic detection of microbial products is essential for the initiation of an innate immune response against intracellular pathogens such as Mycobacterium tuberculosis (Mtb). During Mtb infection of macrophages, activation of cytosolic surveillance pathways is dependent on the mycobacterial ESX-1 secretion system and leads to type I interferon (IFN) and interleukin-1β (IL-1β) production. Whereas the inflammasome regulates IL-1β secretion, the receptor(s) responsible for the activation of type I IFNs has remained elusive. We demonstrate that the cytosolic DNA sensor cyclic GMP-AMP synthase (cGAS) is essential for initiating an IFN response to Mtb infection. cGAS associates with Mtb DNA in the cytosol to stimulate cyclic GAMP (cGAMP) synthesis. Notably, activation of cGAS-dependent cytosolic host responses can be uncoupled from inflammasome activation by modulating the secretion of ESX-1 substrates. Our findings identify cGAS as an innate sensor of Mtb and provide insight into how ESX-1 controls the activation of specific intracellular recognition pathways.

  8. [The development of tuberculosis control and tuberculosis epidemiology in East Germany].

    PubMed

    Steinbrück, P

    1983-01-01

    The fight against tuberculosis in the German Democratic Republic was performed from the very beginning as a task of the state and the society; it was developed according to the progress of economic possibilities and the epidemiological situation. The contribution of the community and of the social-economic development on tuberculosis epidemiology has proved to be decisively important factors in tuberculosis control. The specific methods applied in tuberculosis control in the course of more than 30 years have changed in their importance effectiveness and efficiency with the reduction of the tuberculosis problem and the development of new techniques. Therefore a continuous evaluation of the tuberculosis situation is necessary to recognize the most effective approach. By reducing the estimated annual infection rate to less than 0.05%, the incidence of smear positive pulmonary tuberculosis to less than 5/100,000 and the practical disappearance of tuberculosis among children tuberculosis has become an endemic localized disease among predominantly old citizens. People's mass x-ray examinations have considerably lost their value for finding tuberculosis. Early coverage and examination of persons with respiratory symptoms (21-days-coughers), of contact persons and high risk groups will determine the future activities of the chest clinics. Their integration into the system of outpatient clinics and the system of primary health care were an important step on this way. Successful treatment of each case of tuberculosis is now possible and must be attained. Early case finding + treatment considered as an united activity has become the decisively important measure in the control of tuberculosis. The endemic foci of tuberculosis in some communities have to be surveyed and eliminated with priority. Moreover, the cooperation of all physicians of public health is necessary. Only by this way tuberculosis can be eradicated in GDR in a defined time. (Aim of WHO and IUaT: 1 case of

  9. A Novel Reporter Phage To Detect Tuberculosis and Rifampin Resistance in a High-HIV-Burden Population

    PubMed Central

    Pym, Alexander; Jain, Paras; Munsamy, Vanisha; Wolf, Allison; Karim, Farina; Jacobs, William R.; Larsen, Michelle H.

    2015-01-01

    Improved diagnostics and drug susceptibility testing for Mycobacterium tuberculosis are urgently needed. We developed a more powerful mycobacteriophage (Φ2GFP10) with a fluorescent reporter. Fluorescence-activated cell sorting (FACS) allows for rapid enumeration of metabolically active bacilli after phage infection. We compared the reporter phage assay to GeneXpert MTB/RIF for detection of M. tuberculosis and rifampin (RIF) resistance in sputum. Patients suspected to have tuberculosis were prospectively enrolled in Durban, South Africa. Sputum was incubated with Φ2GFP10, in the presence and absence of RIF, and bacilli were enumerated using FACS. Sensitivity and specificity were compared to those of GeneXpert MTB/RIF with an M. tuberculosis culture as the reference standard. A total of 158 patients were prospectively enrolled. Overall sensitivity for M. tuberculosis was 95.90% (95% confidence interval (CI), 90.69% to 98.64%), and specificity was 83.33% (95% CI, 67.18% to 93.59%). In acid-fast bacillus (AFB)-negative sputum, sensitivity was 88.89% (95% CI, 73.92% to 96.82%), and specificity was 83.33% (95% CI, 67.18% to 93.59%). Sensitivity for RIF-resistant M. tuberculosis in AFB-negative sputum was 90.00% (95% CI, 55.46% to 98.34%), and specificity was 91.94% (95% CI, 82.16% to 97.30%). Compared to GeneXpert, the reporter phage was more sensitive in AFB smear-negative sputum, but specificity was lower. The Φ2GFP10 reporter phage showed high sensitivity for detection of M. tuberculosis and RIF resistance, including in AFB-negative sputum, and has the potential to improve phenotypic testing for complex drug resistance, paucibacillary sputum, response to treatment, and detection of mixed infection in clinical specimens. PMID:25926493

  10. The impact of IFN-γ receptor on SLPI expression in active tuberculosis: association with disease severity.

    PubMed

    Tateosian, Nancy L; Pasquinelli, Virginia; Hernández Del Pino, Rodrigo E; Ambrosi, Nella; Guerrieri, Diego; Pedraza-Sánchez, Sigifredo; Santucci, Natalia; D'Attilio, Luciano; Pellegrini, Joaquín; Araujo-Solis, María A; Musella, Rosa M; Palmero, Domingo J; Hernandez-Pando, Rogelio; Garcia, Verónica E; Chuluyan, H Eduardo

    2014-05-01

    Interferon (IFN)-γ displays a critical role in tuberculosis (TB), modulating the innate and adaptive immune responses. Previously, we reported that secretory leukocyte protease inhibitor (SLPI) is a pattern recognition receptor with anti-mycobacterial activity against Mycobacterium tuberculosis (Mtb). Herein, we determined whether IFN-γ modulated the levels of SLPI in TB patients. Plasma levels of SLPI and IFN-γ were studied in healthy donors (HDs) and TB patients. Peripheral blood mononuclear cells from HDs and patients with TB or defective IFN-γ receptor 1* were stimulated with Mtb antigen and SLPI, and IFN-γR expression levels were measured. Both SLPI and IFN-γ were significantly enhanced in plasma from those with TB compared with HDs. A direct association between SLPI levels and the severity of TB was detected. In addition, Mtb antigen stimulation decreased the SLPI produced by peripheral blood mononuclear cells from HDs, but not from TB or IFN-γR patients. Neutralization of IFN-γ reversed the inhibition of SLPI induced by Mtb antigen in HDs, but not in TB patients. Furthermore, recombinant IFN-γ was unable to modify the expression of SLPI in TB patients. Finally, IFN-γR expression was lower in TB compared with HD peripheral blood mononuclear cells. These results show that Mtb-induced IFN-γ down-modulated SLPI levels by signaling through the IFN-γR in HDs. This inhibitory mechanism was not observed in TB, probably because of the low expression of IFN-γR detected in these individuals.

  11. Crystal Structures of the Response Regulator DosR From Mycobacterium Tuberculosis Suggest a Helix Rearrangement Mechanism for Phosphorylation Activation

    SciTech Connect

    Wisedchaisri, G.; Wu, M.; Sherman, D.R.; Hol, W.G.J.

    2009-05-26

    The response regulator DosR is essential for promoting long-term survival of Mycobacterium tuberculosis under low oxygen conditions in a dormant state and may be responsible for latent tuberculosis in one-third of the world's population. Here, we report crystal structures of full-length unphosphorylated DosR at 2.2 {angstrom} resolution and its C-terminal DNA-binding domain at 1.7 {angstrom} resolution. The full-length DosR structure reveals several features never seen before in other response regulators. The N-terminal domain of the full-length DosR structure has an unexpected ({beta}{alpha}){sub 4} topology instead of the canonical ({beta}{alpha}){sub 5} fold observed in other response regulators. The linker region adopts a unique conformation that contains two helices forming a four-helix bundle with two helices from another subunit, resulting in dimer formation. The C-terminal domain in the full-length DosR structure displays a novel location of helix {alpha}10, which allows Gln199 to interact with the catalytic Asp54 residue of the N-terminal domain. In contrast, the structure of the DosR C-terminal domain alone displays a remarkable unstructured conformation for helix {alpha}10 residues, different from the well-defined helical conformations in all other known structures, indicating considerable flexibility within the C-terminal domain. Our structures suggest a mode of DosR activation by phosphorylation via a helix rearrangement mechanism.

  12. Prime Suspect, Second Row Center

    ERIC Educational Resources Information Center

    Laird, Ellen A.

    2011-01-01

    His father had been hacked to death in his own bed with an ax the previous November. His mother was similarly brutalized and left for dead with her husband but survived. On the last Monday of that August, after several months and many investigative twists, turns, and fumbles, there sat the son--the prime suspect--in Ellen Laird's literature class,…

  13. Suspect identification by facial features.

    PubMed

    Lee, Eric; Whalen, Thomas; Sakalauskas, John; Baigent, Glen; Bisesar, Chandra; McCarthy, Andrew; Reid, Glenda; Wotton, Cynthia

    2004-06-10

    Often during criminal investigations, witnesses must examine photographs of known offenders, colloquially called 'mug shots'. As witnesses view increasing numbers of mug shots that are presented in an arbitrary order, they become more likely to identify the wrong suspect. An alternative is a subjective feature-based mug shot retrieval system in which witnesses first complete a questionnaire about the appearance of the suspect, and then examine photographs in order of decreasing resemblance to their description. In the first experiment, this approach is found to be more efficient and more accurate than searching an album. The next three experiments show that it makes little difference if the witness has seen the suspect in person or only seen a photograph. In the last two experiments, it is shown that the feature-based retrieval system is effective even when the witness has seen the suspect in realistic natural settings. The results show that the main conclusions drawn from previous studies, where witnesses searched for faces seen only in photographs, also apply when witnesses are searching for a face that they saw live in naturalistic settings. Additionally, it is shown that is it better to have two raters than one create the database, but that more than two raters yield rapidly diminishing returns for the extra cost.

  14. Characteristics of Korean patients with suspected Creutzfeldt-Jakob disease with 14-3-3 protein in cerebrospinal fluid: Preliminary study of the Korean Creutzfeldt-Jakob disease active surveillance program

    PubMed Central

    Lim, Jae-Sung; Kwon, Hyung-Min; Jang, Jae-Won; Ju, Young-Ran; Kim, SuYeon; Park, Young Ho; Park, So Young; Kim, SangYun

    2015-01-01

    Abstract Although Korea had a national surveillance system for Creutzfeldt-Jakob disease (CJD), it was mainly dependent on attending physician's reports. Thus, little prospective data about the epidemiology, characteristics, and final diagnoses of suspected patients were available. We have established a nationwide network for the active surveillance of patients with suspected CJD. When the requested cerebrospinal fluid (CSF) samples tested positive for 14-3-3 protein, we investigated the clinical characteristics of the corresponding patients and followed them until their final diagnoses were confirmed. A total of 218 samples were requested for CSF assays from May 2010 to August 2012, and 106 (48.6%) were positive for 14-3-3 protein. In 89 patients with complete clinical data, 38 (42.7%) were diagnosed with probable CJD and the estimated annual occurrence of CJD was 16.3 persons-per-year. The most common diagnoses of the remainder were central nervous system infection and any-cause encephalopathy. Non-CJD subjects showed worse initial consciousness levels than CJD patients. This preliminary study showed that the number of reported cases of CJD and the true positivity rates of CSF 14-3-3 protein assays were both low in Korea. An active surveillance system is urgently needed to provide the latest nationwide epidemiological data of CJD. PMID:25996401

  15. Characteristics of Korean patients with suspected Creutzfeldt-Jakob disease with 14-3-3 protein in cerebrospinal fluid: Preliminary study of the Korean Creutzfeldt-Jakob disease active surveillance program.

    PubMed

    Lim, Jae-Sung; Kwon, Hyung-Min; Jang, Jae-Won; Ju, Young-Ran; Kim, SuYeon; Park, Young Ho; Park, So Young; Kim, SangYun

    2015-01-01

    Although Korea had a national surveillance system for Creutzfeldt-Jakob disease (CJD), it was mainly dependent on attending physician's reports. Thus, little prospective data about the epidemiology, characteristics, and final diagnoses of suspected patients were available. We have established a nationwide network for the active surveillance of patients with suspected CJD. When the requested cerebrospinal fluid (CSF) samples tested positive for 14-3-3 protein, we investigated the clinical characteristics of the corresponding patients and followed them until their final diagnoses were confirmed. A total of 218 samples were requested for CSF assays from May 2010 to August 2012, and 106 (48.6%) were positive for 14-3-3 protein. In 89 patients with complete clinical data, 38 (42.7%) were diagnosed with probable CJD and the estimated annual occurrence of CJD was 16.3 persons-per-year. The most common diagnoses of the remainder were central nervous system infection and any-cause encephalopathy. Non-CJD subjects showed worse initial consciousness levels than CJD patients. This preliminary study showed that the number of reported cases of CJD and the true positivity rates of CSF 14-3-3 protein assays were both low in Korea. An active surveillance system is urgently needed to provide the latest nationwide epidemiological data of CJD.

  16. Immune activation of the host cell induces drug tolerance in Mycobacterium tuberculosis both in vitro and in vivo

    PubMed Central

    Liu, Yancheng; Tan, Shumin; Huang, Lu; Abramovitch, Robert B.; Rohde, Kyle H.; Zimmerman, Matthew D.; Chen, Chao; Dartois, Véronique; VanderVen, Brian C.

    2016-01-01

    Successful chemotherapy against Mycobacterium tuberculosis (Mtb) must eradicate the bacterium within the context of its host cell. However, our understanding of the impact of this environment on antimycobacterial drug action remains incomplete. Intriguingly, we find that Mtb in myeloid cells isolated from the lungs of experimentally infected mice exhibit tolerance to both isoniazid and rifampin to a degree proportional to the activation status of the host cells. These data are confirmed by in vitro infections of resting versus activated macrophages where cytokine-mediated activation renders Mtb tolerant to four frontline drugs. Transcriptional analysis of intracellular Mtb exposed to drugs identified a set of genes common to all four drugs. The data imply a causal linkage between a loss of fitness caused by drug action and Mtb’s sensitivity to host-derived stresses. Interestingly, the environmental context exerts a more dominant impact on Mtb gene expression than the pressure on the drugs’ primary targets. Mtb’s stress responses to drugs resemble those mobilized after cytokine activation of the host cell. Although host-derived stresses are antimicrobial in nature, they negatively affect drug efficacy. Together, our findings demonstrate that the macrophage environment dominates Mtb’s response to drug pressure and suggest novel routes for future drug discovery programs. PMID:27114608

  17. Carbamidocyclophanes F and G with Anti-Mycobacterium tuberculosis Activity from the Cultured Freshwater Cyanobacterium Nostoc sp.

    PubMed

    Luo, Shangwen; Kang, Hahk-Soo; Krunic, Aleksej; Chlipala, George E; Cai, Geping; Chen, Wei-Lun; Franzblau, Scott G; Swanson, Steven M; Orjala, Jimmy

    2014-01-15

    Two new (1 and 2) and three known (3-5) carbamidocyclophanes were isolated from a cultured freshwater cyanobacterium Nostoc sp. (UIC 10274) obtained from a sample collected at Des Plaines, Illinois. Their planar structures and stereoconfigurations were determined by extensive spectroscopic analysis including 1D/2D NMR experiments, HRESIMS as well as CD spectroscopy. Carbamidocyclophane F (1) showed potent anti-Mycobacterium tuberculosis activity in the microplate Alamar blue assay and low-oxygen-recovery assay with MIC values of 0.8 and 5.4 µM, respectively. Carbamidocyclophane F (1) also displayed antimicrobial activities against the gram positive bacteria Staphylococcus aureus and Enterococcus faecalis with MIC values of 0.1 and 0.2 µM, respectively. Carbamidocyclophane F (1) and Carbamidocyclophane G (2) both showed antiproliferative activity against MDA-MB-435 and HT-29 human cancer cell lines with IC50 values in the range from 0.5 to 0.7 µM.

  18. Association of autophagy-related IRGM polymorphisms with latent versus active tuberculosis infection in a Chinese population.

    PubMed

    Lu, Yanjun; Li, Qian; Peng, Jing; Zhu, Yaowu; Wang, Feng; Wang, Chunyu; Wang, Xiong

    2016-03-01

    The autophagy-related immunity-related GTPase family M protein, IRGM, plays an important role in the defense against tuberculosis (TB) infection. IRGM polymorphisms are associated with TB infection susceptibility, and recent studies demonstrate host genetic differences between active and latent TB. Here, we investigated the association between IRGM polymorphisms and TB infection type in a Chinese population. We recruited 268 and 321 patients with confirmed or latent TB, respectively, and 475 TB-free healthy controls. Three single nucleotide polymorphisms, rs10065172, rs10051924, and rs13361189 within IRGM were genotyped using TaqMan-based assays. Interferon-gamma release levels were tested by T-SPOT. rs10065172 (P = 0.024, OR 0.67 (95% CI 0.48-0.95)), rs10051924 (P = 0.01, OR 0.64 (95% CI 0.46-0.90)), and rs13361189 (P = 0.055, OR 0.72 (95% CI 0.51-1.01)) were associated with a protective role against latent TB progression. Haplotype analysis showed that TCC was protective for latent TB (P = 0.022, OR 0.74 (95% CI 0.57-0.96)) whereas TTC conferred a higher risk of active TB. Additionally, patients with the rs10065172 TT genotype had a higher response to TB specific antigens. Thus, IRGM polymorphism differences between latent and active TB suggests that genetic differences in autophagy might partly affect host TB infection status.

  19. Cellular interactions in bovine tuberculosis: release of active mycobacteria from infected macrophages by antigen‐stimulated T cells

    PubMed Central

    Liébana, E; Aranaz, A; Aldwell, F E; McNair, J; Neill, S D; Smyth, A J; Pollock, J M

    2000-01-01

    The outcome of Mycobacterium bovis infections depends on the interactions of infected macrophages with T lymphocytes. Several studies in humans and in mouse models have suggested an important role for cytotoxicity in the protective immune response to mycobacterial infections, and both CD4+ and CD8+ T cells have been shown to elicit appropriate cytolytic activity. The present study investigated in vitro interactions of T cells with M. bovis‐infected macrophages in bovine tuberculosis. The results showed that following interaction with antigen‐stimulated peripheral blood mononuclear cells (PBMC) from infected cattle, there was an increased presence of M. bovis in the extracellular compartment of infected macrophage cultures, as measured by incorporation of [3H]uracil into mycobacterial RNA. Furthermore, out of a panel of T‐cell clones from infected cattle, it was found that a higher proportion of CD8+ clones produced an increase in the number of metabolically active extracellular M. bovis organisms compared with CD4+ clones. Finally, a positive correlation between percentage of antigen‐dependent release of mycobacteria and total uracil uptake by M. bovis within culture systems was detected. This could be regarded as an indication of preferential intracellular control of mycobacteria by activated macrophages. PMID:10651937

  20. Conformational Analysis of an Antibacterial Cyclodepsipeptide Active against Mycobacterium tuberculosis by a Combined ROE and RDC Analysis.

    PubMed

    Fredersdorf, Maic; Kurz, Michael; Bauer, Armin; Ebert, Marc-Olivier; Rigling, Carla; Lannes, Laurie; Thiele, Christina Marie

    2017-01-20

    Griselimycin (GM) and methylgriselimycin (MGM), naturally produced by microorganisms of the genus Streptomyces, are cyclic depsipeptides composed of ten amino acids. They exhibit antibacterial activity against Mycobacterium species by inhibiting the sliding clamp of prokaryotic DNA polymerase III and are therefore considered as potential anti-tuberculosis drugs. The difference between the peptides is the presence of l-(R)-4-methyl-proline in MGM instead of l-proline in GM at position 8 of the amino acid sequence. Methylation increases both metabolic stability and activity of MGM compared to GM. To get deeper insight into the structure-activity relationship, the solution structure of the cyclic part of MGM was determined using rotating-frame nuclear Overhauser effect (ROE) distance restraints and residual dipolar couplings (RDC). The structure of MGM in solution is compared to the structure of GM in a co-crystal with DNA polymerase III subunit beta. As a result, a highly defined structural model of MGM is obtained, which shows related characteristics to the bound GM.

  1. [A rare case of an extra-pulmonary tuberculosis].

    PubMed

    Windler, B

    1989-01-01

    This is a case report on a 42-year old West. German woman suspected of suffering from an extrapulmonary manifestation of mucous membrane tuberculosis of the ethmoid sinuses. The condition did not improve after application of specific chemotherapy. Only after histological examination of several tissue samples was a direct connection with initial stage Wegeners granulomatosis established. Attention must be drawn to the fact that in isolated cases the differentiation between the histological diagnosis of tuberculosis versus Wegeners disease is complex and often faulty.

  2. Evaluation of the inhibitory activity of (aza)isoindolinone-type compounds: toward in vitro InhA action, Mycobacterium tuberculosis growth and mycolic acid biosynthesis.

    PubMed

    Chollet, Aurélien; Stigliani, Jean-Luc; Pasca, Maria Rosalia; Mori, Giorgia; Lherbet, Christian; Constant, Patricia; Quémard, Annaïk; Bernadou, Jean; Pratviel, Geneviève; Bernardes-Génisson, Vania

    2016-11-01

    Inhibitors of the Mycobacterium tuberculosis enoyl-ACP reductase (InhA) are considered as potential promising therapeutics for the treatment of tuberculosis. Previously, we reported that azaisoindolinone-type compounds displayed, in vitro, inhibitory activity toward InhA. Herein, we describe chemical modifications of azaisoindolinone scaffold, the synthesis of 15 new compounds and their evaluations toward the in vitro InhA activity. Based on these results, a structure-InhA inhibitory activity relationship analysis and a molecular docking study, using the conformation of InhA found in the 2H7M crystal structure, were carried out to predict a possible mode of interaction of the best (aza)isoindolinone-type inhibitors with InhA in vitro. Then, the work was extended toward evaluations of these compounds against Mycobacterium tuberculosis (Mtb) growth, and finally, some of them were also investigated in respect of their ability to inhibit mycolic acid biosynthesis inside mycobacteria. Although, some azaisoindolinones were able to inhibit InhA activity and Mtb growth in vitro, they did not inhibit the mycolic acid biosynthesis inside Mtb.

  3. [Mycobacterium tuberculosis infection following organ transplantation].

    PubMed

    Haas, Charles; Le Jeunne, Claire

    2006-11-01

    In transplant recipients, immunosuppressive treatment affects cell-mediated immunity and increases the risk of tuberculosis. Tuberculosis may be transmitted by the donor organ or occur de novo, but such cases are rare. The vast majority of cases of active tuberculosis in transplant recipients result from reactivation of latent Mycobacterium tuberculosis infection. The incidence varies from one region of the globe to another, from 0.5-1.0% in North America, to 0.36-5.5% in Europe and 7.0-11.8% in India. The incidence of tuberculosis among transplant recipients is much higher than in the general population. Diabetes mellitus, renal impairment, systemic lupus erythematosus, chronic liver disease and AIDS all increase the risk of post-transplant tuberculosis. Extrapulmonary and disseminated forms are frequent in this setting. The diagnosis of tuberculosis in transplant recipients is often difficult, and treatment is frequently delayed. Tuberculosis can be life-threatening in such cases. Treatment is difficult because rifampicin is a cytochrome P450 inducer (leading to reduced levels of cyclosporine), and because the hepatotoxicity of isoniazid, rifampin and pyrazinamide is frequently increased in transplant recipients. Treatment of latent tuberculosis before transplantation markedly reduces the risk of developing active tuberculosis after transplantation.

  4. Tuberculosis control activities before and after Hurricane Sandy--northeast and mid-Atlantic states, 2012.

    PubMed

    2013-03-22

    On October 29, 2012, Hurricane Sandy struck the U.S. northeast and mid-Atlantic seaboard; the effects of the storm extended to southeastern and midwestern states and to eastern Canada. At the time, 1,899 residents in the most affected areas were undergoing treatment for tuberculosis (TB) disease or infection. To ascertain the operational abilities of state and local TB programs during and after the storm and to determine whether lessons learned from a previous hurricane were effective in ensuring continuity of TB patient care, CDC interviewed staff members at all of the affected state and city TB control programs, including those in areas with power outages and flooded streets, tunnels, and subway lines. The interviews determined that continuity of care for TB patients in programs affected by Hurricane Sandy was better preserved than it had been during and after Hurricane Katrina in August 2005. This improvement might be attributed to 1) preparedness measures learned from Hurricane Katrina (e.g., preparing line lists of patients, providing patients with as-needed medications, and making back-up copies of patient records in advance of the storm) and 2) less widespread displacement of persons after Hurricane Sandy than occurred after Hurricane Katrina. Maintaining readiness among clinicians and TB control programs to respond to natural disasters remains essential to protecting public health and preserving TB patients' continuity of care.

  5. Activism on rifapentine pricing: removing cost barriers to improve the uptake of tuberculosis research innovations

    PubMed Central

    Frick, M.; Lessem, E.; Kanouse, J.; Wegener, D.; Mingote, L. Ruiz

    2014-01-01

    As recent advances have been made in developing tools to fight tuberculosis (TB), there is also a trend towards increasing advocacy by the civil society for TB research and access. One recent successful effort to increase access to treatment options for TB involved a collaborative effort to identify the need for and barriers to the use of rifapentine (RPT) use in the United States. Survey responses confirmed the under-utilization of RPT: 82% of survey respondents selected cost as a significant or potential barrier to use. Survey results provided data to support a year-long advocacy campaign urging the drug company Sanofi to lower the price of RPT. This campaign was based on a common evidence base built in part by the stakeholders themselves. After multiple engagements with communities and providers, Sanofi US announced on 12 December 2013 that they would drop the price of RPT to US$32 per blister pack of 32 tablets for US public health programs. While further work remains to secure access to RPT in the United States and worldwide, the lowering of the price of RPT reflects the positive impact that collaborative advocacy can accomplish, and sets an example for other drug companies to follow. PMID:26400702

  6. Activism on rifapentine pricing: removing cost barriers to improve the uptake of tuberculosis research innovations.

    PubMed

    DeLuca, A; Frick, M; Lessem, E; Kanouse, J; Wegener, D; Mingote, L Ruiz

    2014-12-21

    As recent advances have been made in developing tools to fight tuberculosis (TB), there is also a trend towards increasing advocacy by the civil society for TB research and access. One recent successful effort to increase access to treatment options for TB involved a collaborative effort to identify the need for and barriers to the use of rifapentine (RPT) use in the United States. Survey responses confirmed the under-utilization of RPT: 82% of survey respondents selected cost as a significant or potential barrier to use. Survey results provided data to support a year-long advocacy campaign urging the drug company Sanofi to lower the price of RPT. This campaign was based on a common evidence base built in part by the stakeholders themselves. After multiple engagements with communities and providers, Sanofi US announced on 12 December 2013 that they would drop the price of RPT to US$32 per blister pack of 32 tablets for US public health programs. While further work remains to secure access to RPT in the United States and worldwide, the lowering of the price of RPT reflects the positive impact that collaborative advocacy can accomplish, and sets an example for other drug companies to follow.

  7. The Mycobacterium tuberculosis Ag85A is a novel diacylglycerol acyltransferase involved in lipid body formation.

    PubMed

    Elamin, Ayssar A; Stehr, Matthias; Spallek, Ralf; Rohde, Manfred; Singh, Mahavir

    2011-09-01

    Mycobacterium tuberculosis accumulates large amounts of triacylglycerol (TAG) which acts as storage compounds for energy and carbon. The mycobacterial triacylglycerols stored in the form of intracellular lipid droplets are essential for long-term survival of M. tuberculosis during a dormant state. We report here that when the M. tuberculosis mycolytransferase Ag85A is overexpressed in Mycobacterium smegmatis mc(2)155, cell morphology was changed and the cells became grossly enlarged. A massive formation of lipid bodies and a change in lipid pattern was observed simultaneously. We suspected a possible role of Ag85A in the acyl lipid metabolism and discovered that the enzyme possesses acyl-CoA:diacylglycerol acyltransferase (DGAT) activity in addition to its well-known function as mycolyltransferase. Ag85A mediates the transesterification of diacylglycerol using long-chain acyl-CoA as acyl donors. The K(m) and K(cat) values for palmitoleoyl-coenzyme A were 390 µM and 55.54 min(-1) respectively. A docking model suggests that palmitoleoyl-coenzyme A and 1,2-dipalmitin occupy the same active site as trehalose 6,6'-dimycolate and trehalose 6'-monomycolate. The site-directed Ser126Ala mutation of the active site proved that this residue is involved in the catalytic activity of this enzyme. Although not proven conclusively for dormant stage of M. tuberculosis, our novel finding about the synthesis of TAGs by Ag85A strongly suggests that Ag85A may play a significant role in the formation of lipid storage bodies and thus also in the establishment and maintenance of a persistent tuberculosis infection.

  8. Structure and Proposed Activity of a Member of the VapBC Family of Toxin-Antitoxin Systems: VapBC-5 from Mycobacterium tuberculosis

    SciTech Connect

    Miallau, L.; Faller, M.; Chiang, J.; Arbing, M.; Guo, F.; Cascio, D.; Eisenberg, D.

    2009-03-02

    In prokaryotes, cognate toxin-antitoxin pairs have long been known, but no three-dimensional structure has been available for any given complex from Mycobacterium tuberculosis. Here we report the crystal structure and activity of a member of the VapBC family of complexes from M. tuberculosis. The toxin VapC-5 is a compact, 150 residues, two domain {alpha}/{beta} protein. Bent around the toxin is the VapB-5 antitoxin, a 33-residue {alpha}-helix. Assays suggest that the toxin is an Mg-enabled endoribonuclease, inhibited by the antitoxin. The lack of DNase activity is consistent with earlier suggestions that the complex represses its own operon. Furthermore, analysis of the interactions in the binding of the antitoxin to the toxin suggest that exquisite control is required to protect the bacteria cell from toxic VapC-5.

  9. Tuberculosis infection causing intestinal perforations in 2 patients with systemic lupus erythematosus.

    PubMed

    González, Luis A; Muñoz, Carolina; Restrepo, Mauricio; Vanegas, Adriana Lucía; Vásquez, Gloria

    2014-08-01

    Patients with systemic lupus erythematosus (SLE) have a higher incidence rate of tuberculosis and a more frequent extrapulmonary involvement than the general population. We present 2 SLE patients who developed gastrointestinal tuberculosis complicated with intestinal perforation, a rare but serious complication that could be confused with lupus-associated intestinal vasculitis. Opportunistic infections such as tuberculosis must be suspected in SLE patients with abdominal symptoms on immunosuppressive therapy because its early recognition could prevent catastrophic complications such as intestinal perforation and subsequent peritonitis.

  10. [Extrapulmonary tuberculosis].

    PubMed

    Mazza-Stalder, J; Nicod, L; Janssens, J-P

    2012-04-01

    Extrapulmonary tuberculosis represents an increasing proportion of all cases of tuberculosis reaching 20 to 40% according to published reports. Extrapulmonary TB is found in a higher proportion of women, black people and immunosuppressed individuals. A significant proportion of cases have a normal chest X-Ray at the time of diagnosis. The most frequent clinical presentations are lymphadenitis, pleuritis and osteoarticular TB. Peritoneal, urogenital or meningeal tuberculosis are less frequent, and their diagnosis is often difficult due to the often wide differential diagnosis and the low sensitivity of diagnostic tests including cultures and genetic amplification tests. The key clinical elements are reported and for each form the diagnostic yield of available tests. International therapeutic recommendations and practical issues are reviewed according to clinical presentation.

  11. MULTIFOCAL TUBERCULOSIS VERRUCOSA CUTIS

    PubMed Central

    Rajan, Jiby; Mathai, Ashok Thomas; Prasad, P V S; Kaviarasan, P K

    2011-01-01

    Tuberculosis has been a well-known affliction of human kind, since antiquity. Cutaneous tuberculosis constitutes only a small proportion of extra pulmonary tuberculosis and multifocal involvement of cutaneous tuberculosis is an even rarer manifestation. We report one such case of multifocal tuberculosis verrucosa cutis in a 17-year old male patient in the absence of any primary tuberculous focus. PMID:21772603

  12. Tuberculosis of the Gallbladder

    PubMed Central

    Kumar, K.; Ayub, M.; Kumar, Mohan; Keswani, N. K.

    2000-01-01

    Analysis of 5 patients with gallbladder tuberculosis who had open cholecystectomy and review of literature have shown that, although still rare it presents as a part of systemic miliary tuberculosis, abdominal tuberculosis, isolated gallbladder tuberculosis and as acalculus cholecystitis in anergic patients. There are no pathognomonic signs, the diagnosis depends on suspicion of tuberculosis, peroperative findings and histological examination. PMID:10977119

  13. Implications of binding mode and active site flexibility for inhibitor potency against the salicylate synthase from Mycobacterium tuberculosis.

    PubMed

    Chi, Gamma; Manos-Turvey, Alexandra; O'Connor, Patrick D; Johnston, Jodie M; Evans, Genevieve L; Baker, Edward N; Payne, Richard J; Lott, J Shaun; Bulloch, Esther M M

    2012-06-19

    MbtI is the salicylate synthase that catalyzes the first committed step in the synthesis of the iron chelating compound mycobactin in Mycobacterium tuberculosis. We previously developed a series of aromatic inhibitors against MbtI based on the reaction intermediate for this enzyme, isochorismate. The most potent of these inhibitors had hydrophobic substituents, ranging in size from a methyl to a phenyl group, appended to the terminal alkene of the enolpyruvyl group. These compounds exhibited low micromolar inhibition constants against MbtI and were at least an order of magnitude more potent than the parental compound for the series, which carries a native enolpyruvyl group. In this study, we sought to understand how the substituted enolpyruvyl group confers greater potency, by determining cocrystal structures of MbtI with six inhibitors from the series. A switch in binding mode at the MbtI active site is observed for inhibitors carrying a substituted enolpyruvyl group, relative to the parental compound. Computational studies suggest that the change in binding mode, and higher potency, is due to the effect of the substituents on the conformational landscape of the core inhibitor structure. The crystal structures and fluorescence-based thermal shift assays indicate that substituents larger than a methyl group are accommodated in the MbtI active site through significant but localized flexibility in the peptide backbone. These findings have implications for the design of improved inhibitors of MbtI, as well as other chorismate-utilizing enzymes from this family.

  14. Dynamic active-site protection by the M. tuberculosis protein tyrosine phosphatase PtpB lid domain.

    PubMed

    Flynn, E Megan; Hanson, Jeffrey A; Alber, Tom; Yang, Haw

    2010-04-07

    The Mycobacterium tuberculosis protein tyrosine phosphatase PtpB shows resistance to the oxidative conditions that prevail within an infected host macrophage, but the mechanism of this molecular adaptation is unknown. Crystal structures of PtpB revealed previously that a closed, two-helix lid covers the active site. By measuring single-molecule Forster-type resonance energy transfer to probe the dynamics of two helices that constitute the lid, we obtained direct evidence for large, spontaneous opening transitions of PtpB with the closed form of both helices favored approximately 3:1. Despite similar populations of conformers, the two helices move asynchronously as demonstrated by different opening and closing rates under our experimental conditions. Assuming that lid closure excludes oxidant, the rates of opening and closing quantitatively accounted for the slow observed rate of oxidative inactivation. Increasing solvent viscosity using glycerol but not PEG8000 resulted in higher rates of oxidative inactivation due to an increase in the population of open conformers. These results establish that the rapid conformational gating of the PtpB lid constitutes a reversible physical blockade that transiently masks the active site and retards oxidative inactivation.

  15. In Vitro Activity of Copper(II) Complexes, Loaded or Unloaded into a Nanostructured Lipid System, against Mycobacterium tuberculosis

    PubMed Central

    da Silva, Patricia B.; de Souza, Paula C.; Calixto, Giovana Maria Fioramonti; Lopes, Erica de O.; Frem, Regina C. G.; Netto, Adelino V. G.; Mauro, Antonio E.; Pavan, Fernando R.; Chorilli, Marlus

    2016-01-01

    Tuberculosis (TB) is an infectious disease caused mainly by the bacillus Mycobacterium tuberculosis (Mtb), presenting 9.5 million new cases and 1.5 million deaths in 2014. The aim of this study was to evaluate a nanostructured lipid system (NLS) composed of 10% phase oil (cholesterol), 10% surfactant (soy phosphatidylcholine, sodium oleate), and Eumulgin® HRE 40 ([castor oil polyoxyl-40-hydrogenated] in a proportion of 3:6:8), and an 80% aqueous phase (phosphate buffer pH = 7.4) as a tactic to enhance the in vitro anti-Mtb activity of the copper(II) complexes [CuCl2(INH)2]·H2O (1), [Cu(NCS)2(INH)2]·5H2O (2) and [Cu(NCO)2(INH)2]·4H2O (3). The Cu(II) complex-loaded NLS displayed sizes ranging from 169.5 ± 0.7095 to 211.1 ± 0.8963 nm, polydispersity index (PDI) varying from 0.135 ± 0.0130 to 0.236 ± 0.00100, and zeta potential ranging from −0.00690 ± 0.0896 to −8.43 ± 1.63 mV. Rheological analysis showed that the formulations behave as non-Newtonian fluids of the pseudoplastic and viscoelastic type. Antimycobacterial activities of the free complexes and NLS-loaded complexes against Mtb H37Rv ATCC 27294 were evaluated by the REMA methodology, and the selectivity index (SI) was calculated using the cytotoxicity index (IC50) against Vero (ATCC® CCL-81), J774A.1 (ATCC® TIB-67), and MRC-5 (ATCC® CCL-171) cell lines. The data suggest that the incorporation of the complexes into NLS improved the inhibitory action against Mtb by 52-, 27-, and 4.7-fold and the SI values by 173-, 43-, and 7-fold for the compounds 1, 2 and 3, respectively. The incorporation of the complexes 1, 2 and 3 into the NLS also resulted in a significant decrease of toxicity towards an alternative model (Artemia salina L.). These findings suggest that the NLS may be considered as a platform for incorporation of metallic complexes aimed at the treatment of TB. PMID:27196901

  16. In Vitro Activity of Copper(II) Complexes, Loaded or Unloaded into a Nanostructured Lipid System, against Mycobacterium tuberculosis.

    PubMed

    Silva, Patricia B da; Souza, Paula C de; Calixto, Giovana Maria Fioramonti; Lopes, Erica de O; Frem, Regina C G; Netto, Adelino V G; Mauro, Antonio E; Pavan, Fernando R; Chorilli, Marlus

    2016-05-17

    Tuberculosis (TB) is an infectious disease caused mainly by the bacillus Mycobacterium tuberculosis (Mtb), presenting 9.5 million new cases and 1.5 million deaths in 2014. The aim of this study was to evaluate a nanostructured lipid system (NLS) composed of 10% phase oil (cholesterol), 10% surfactant (soy phosphatidylcholine, sodium oleate), and Eumulgin(®) HRE 40 ([castor oil polyoxyl-40-hydrogenated] in a proportion of 3:6:8), and an 80% aqueous phase (phosphate buffer pH = 7.4) as a tactic to enhance the in vitro anti-Mtb activity of the copper(II) complexes [CuCl₂(INH)₂]·H₂O (1), [Cu(NCS)₂(INH)₂]·5H₂O (2) and [Cu(NCO)₂(INH)₂]·4H₂O (3). The Cu(II) complex-loaded NLS displayed sizes ranging from 169.5 ± 0.7095 to 211.1 ± 0.8963 nm, polydispersity index (PDI) varying from 0.135 ± 0.0130 to 0.236 ± 0.00100, and zeta potential ranging from -0.00690 ± 0.0896 to -8.43 ± 1.63 mV. Rheological analysis showed that the formulations behave as non-Newtonian fluids of the pseudoplastic and viscoelastic type. Antimycobacterial activities of the free complexes and NLS-loaded complexes against Mtb H37Rv ATCC 27294 were evaluated by the REMA methodology, and the selectivity index (SI) was calculated using the cytotoxicity index (IC50) against Vero (ATCC(®) CCL-81), J774A.1 (ATCC(®) TIB-67), and MRC-5 (ATCC(®) CCL-171) cell lines. The data suggest that the incorporation of the complexes into NLS improved the inhibitory action against Mtb by 52-, 27-, and 4.7-fold and the SI values by 173-, 43-, and 7-fold for the compounds 1, 2 and 3, respectively. The incorporation of the complexes 1, 2 and 3 into the NLS also resulted in a significant decrease of toxicity towards an alternative model (Artemia salina L.). These findings suggest that the NLS may be considered as a platform for incorporation of metallic complexes aimed at the treatment of TB.

  17. Structural mechanics of the pH-dependent activity of beta-carbonic anhydrase from Mycobacterium tuberculosis.

    PubMed

    Covarrubias, Adrian Suarez; Bergfors, Terese; Jones, T Alwyn; Högbom, Martin

    2006-02-24

    Carbonic anhydrases catalyze the reversible hydration of carbon dioxide to form bicarbonate, a reaction required for many functions, including carbon assimilation and pH homeostasis. Carbonic anhydrases are divided into at least three classes and are believed to share a zinc-hydroxide mechanism for carbon dioxide hydration. beta-carbonic anhydrases are broadly spread among the domains of life, and existing structures from different organisms show two distinct active site setups, one with three protein coordinations to the zinc (accessible) and the other with four (blocked). The latter is believed to be inconsistent with the zinc-hydroxide mechanism. The Mycobacterium tuberculosis Rv3588c gene, shown to be required for in vivo growth of the pathogen, encodes a beta-carbonic anhydrase with a steep pH dependence of its activity, being active at pH 8.4 but not at pH 7.5. We have recently solved the structure of this protein, which was a dimeric protein with a blocked active site. Here we present the structure of the thiocyanate complexed protein in a different crystal form. The protein now forms distinct tetramers and shows large structural changes, including a carboxylate shift yielding the accessible active site. This structure demonstrated for the first time that a beta-carbonic anhydrase can switch between the two states. A pH-dependent dimer to tetramer equilibrium was also demonstrated by dynamic light scattering measurements. The data presented here, therefore, suggest a carboxylate shift on/off switch for the enzyme, which may, in turn, be controlled by a dimer-to-tetramer equilibrium.

  18. PD-1/PD-L pathway inhibits M.tb-specific CD4+ T-cell functions and phagocytosis of macrophages in active tuberculosis

    PubMed Central

    Shen, Lei; Gao, Yan; Liu, Yuanyuan; Zhang, Bingyan; Liu, Qianqian; Wu, Jing; Fan, Lin; Ou, Qinfang; Zhang, Wenhong; Shao, Lingyun

    2016-01-01

    The role of the PD-1/PD-L pathway in a murine model of tuberculosis remains controversial regarding viral infections and clinical tuberculosis. We conducted a case-control study to investigate the modulating role and mechanism of the PD-1/PD-L pathway in patients with active tuberculosis. Fifty-nine participants, including 43 active tuberculosis (ATB) patients and 16 healthy controls (HC), were enrolled. Cell surface staining and flow cytometry were used to detect the expressions of PD-1 and its ligands on T cells and monocytes. Intracellular cytokine staining was used to determine the PPD-specific IFN-γ-secreting T-cell proportion. CD4+ T-cell proliferation and macrophage functions were investigated in the presence or absence of PD-1/PD-L pathway blockade. Proportions of both PD-1+CD4+ and PD-L1+CD4+ T cells in ATB patients were more significantly increased than in the HC group (P = 0.0112 and P = 0.0141, respectively). The expressions of PD-1, PD-L1, and PD-L2 on CD14+ monocytes in ATB patients were much higher than those in the HC group (P = 0.0016, P = 0.0001, and P = 0.0088, respectively). Blockade of PD-1 could significantly enhance CD4+ T-cell proliferation (P = 0.0433). Phagocytosis and intracellular killing activity of macrophages increased significantly with PD-1/PD-L pathway blockade. In conclusion, the PD-1/PD-L pathway inhibits not only M.tb-specific CD4+ T-cell-mediated immunity but also innate immunity. PMID:27924827

  19. Psoriatic disease and tuberculosis nowadays.

    PubMed

    Balato, Nicola; Di Costanzo, Luisa; Ayala, Fabio; Balato, Anna; Sanduzzi, Alessandro; Bocchino, Marialuisa

    2012-01-01

    Psoriasis is a chronic, relapsing and remitting inflammatory skin and joint disease that has a prevalence of 2-3% in the world's population, whereas of 1-2% in Europe. The traditional concept of psoriasis as the "healthy people's" disease has been recently revised because of ever-increasing reports of associations with various pathological conditions (hypertension, Crohn's disease, type II diabetes mellitus, obesity, dyslipidemia, metabolic syndrome, infectious conditions). Particularly, advances in psoriasis therapies have introduced biologic agents. All the tumor necrosis factor-alpha inhibitors are associated with an increased risk of developing active disease in patients with latent tuberculosis infection, because of TNF-α key role against Mycobacterium tuberculosis. For this reason, exclusion of active tuberculosis and treatment of latent tuberculosis infection are clinical imperatives prior to starting this therapy. Moreover active surveillance for a history of untreated or partially treated tuberculosis or latent form has already been shown to be effective in reducing the number of incident tuberculosis cases.

  20. Tuberculosis and Cardiovascular Disease: Linking the Epidemics.

    PubMed

    Huaman, Moises A; Henson, David; Ticona, Eduardo; Sterling, Timothy R; Garvy, Beth A

    The burden of tuberculosis and cardiovascular disease (CVD) is enormous worldwide. CVD rates are rapidly increasing in low- and middle-income countries. Public health programs have been challenged with the overlapping tuberculosis and CVD epidemics. Monocyte/macrophages, lymphocytes and cytokines involved in cellular mediated immune responses against Mycobacterium tuberculosis are also main drivers of atherogenesis, suggesting a potential pathogenic role of tuberculosis in CVD via mechanisms that have been described for other pathogens that establish chronic infection and latency. Studies have shown a pro-atherogenic effect of antibody-mediated responses against mycobacterial heat shock protein-65 through cross reaction with self-antigens in human vessels. Furthermore, subsets of mycobacteria actively replicate during latent tuberculosis infection (LTBI), and recent studies suggest that LTBI is associated with persistent chronic inflammation that may lead to CVD. Recent epidemiologic work has shown that the risk of CVD in persons who develop tuberculosis is higher than in persons without a history of tuberculosis, even several years after recovery from tuberculosis. Together, these data suggest that tuberculosis may play a role in the pathogenesis of CVD. Further research to investigate a potential link between tuberculosis and CVD is warranted.

  1. Tuberculosis and Cardiovascular Disease: Linking the Epidemics

    PubMed Central

    Huaman, Moises A.; Henson, David; Ticona, Eduardo; Sterling, Timothy R.; Garvy, Beth A.

    2016-01-01

    The burden of tuberculosis and cardiovascular disease (CVD) is enormous worldwide. CVD rates are rapidly increasing in low- and middle-income countries. Public health programs have been challenged with the overlapping tuberculosis and CVD epidemics. Monocyte/macrophages, lymphocytes and cytokines involved in cellular mediated immune responses against Mycobacterium tuberculosis are also main drivers of atherogenesis, suggesting a potential pathogenic role of tuberculosis in CVD via mechanisms that have been described for other pathogens that establish chronic infection and latency. Studies have shown a pro-atherogenic effect of antibody-mediated responses against mycobacterial heat shock protein-65 through cross reaction with self-antigens in human vessels. Furthermore, subsets of mycobacteria actively replicate during latent tuberculosis infection (LTBI), and recent studies suggest that LTBI is associated with persistent chronic inflammation that may lead to CVD. Recent epidemiologic work has shown that the risk of CVD in persons who develop tuberculosis is higher than in persons without a history of tuberculosis, even several years after recovery from tuberculosis. Together, these data suggest that tuberculosis may play a role in the pathogenesis of CVD. Further research to investigate a potential link between tuberculosis and CVD is warranted. PMID:26835156

  2. Influence of diabetes mellitus and risk factors in activating latent tuberculosis infection: a case for targeted screening in malaysia.

    PubMed

    Swarna Nantha, Y

    2012-10-01

    A review of the epidemiology of tuberculosis, its contributing risk factors (excluding HIV) and the role of screening latent tuberculosis infection in Malaysia was done. Despite the global and domestic decrease in prevalence rates of tuberculosis in the past decade, there is an alarming increase in the trend of non communicable diseases in the country. High prevalence rates of major risk factors leading to reactivation of tuberculosis were seen within the population, with diabetes mellitus being in the forefront. The rising numbers in the ageing population of Malaysia poses a further threat of re-emergence of tuberculosis in the years to come. Economically, screening of diabetic patients with comorbidities for latent tuberculosis infection (LTBI) using two major techniques, namely tuberculin sensitivity (TST) and Interferon gamma release assay tests (IGRA) could be a viable option. The role of future research in the detection of LTBI in the Malaysian setting might be necessary to gauge the disease reservoir before implementing prophylactic measures for high risk groups involved.

  3. Molecular Basis of the Activity and the Regulation of the Eukaryotic-like S/T Protein Kinase PknG from Mycobacterium tuberculosis.

    PubMed

    Lisa, María-Natalia; Gil, Magdalena; André-Leroux, Gwénaëlle; Barilone, Nathalie; Durán, Rosario; Biondi, Ricardo M; Alzari, Pedro M

    2015-06-02

    Tuberculosis remains one of the world's deadliest human diseases, with a high prevalence of antibiotic-resistant Mycobacterium tuberculosis (Mtb) strains. A molecular understanding of processes underlying regulation and adaptation of bacterial physiology may provide novel avenues for the development of antibiotics with unconventional modes of action. Here, we focus on the multidomain S/T protein kinase PknG, a soluble enzyme that controls central metabolism in Actinobacteria and has been linked to Mtb infectivity. Our biochemical and structural studies reveal how different motifs and domains flanking the catalytic core regulate substrate selectivity without significantly affecting the intrinsic kinase activity, whereas a rubredoxin-like domain is shown to downregulate catalysis through specific intramolecular interactions that modulate access to a profound substrate-binding site. Our findings provide the basis for the selective and specific inhibition of PknG, and open new questions about regulation of related bacterial and eukaryotic protein kinases.

  4. HIV and Tuberculosis (TB)

    MedlinePlus

    ... AIDS-Related Opportunistic Infections and Coinfections HIV and Tuberculosis (TB) (Last updated 9/1/2016; last reviewed ... depends on a person’s individual circumstances. What is tuberculosis? Tuberculosis (TB) is a contagious disease that can ...

  5. Tuberculosis: General Information

    MedlinePlus

    TB Elimination Tuberculosis: General Information What is TB? Tuberculosis (TB) is a disease caused by germs that are spread from person ... Viral Hepatitis, STD, and TB Prevention Division of Tuberculosis Elimination CS227840_A What Does a Positive Test ...

  6. Mycobacterium Tuberculosis in Spinal Tuberculosis

    PubMed Central

    Kim, Sung-Sim; Moon, Han-Lim; Kim, Dong-Hyeon

    2017-01-01

    Even in an era of remarkable medical advances, there is an issue of why tuberculosis remains in the list of disastrous diseases, afflicting humans and causing suffering. There has not been a plausible answer to this, and it has been suggested that clinicians and medical scientists could presently not win the war against the tubercle bacilli. With regards to this issue, based on the authors' own clinical and research experiences, in this review, the available literature was revisited in order to address the raised questions and to provide recent information on characteristics of tubercle bacilli and possible ways to more effectively treat tuberculosis. PMID:28243382

  7. Design of Selective Substrates and Activity-Based Probes for Hydrolase Important for Pathogenesis 1 (HIP1) from Mycobacterium tuberculosis

    PubMed Central

    2016-01-01

    Although serine proteases are important mediators of Mycobacterium tuberculosis (Mtb) virulence, there are currently no tools to selectively block or visualize members of this family of enzymes. Selective reporter substrates or activity-based probes (ABPs) could provide a means to monitor infection and response to therapy using imaging methods. Here, we use a combination of substrate selectivity profiling and focused screening to identify optimized reporter substrates and ABPs for the Mtb “Hydrolase important for pathogenesis 1” (Hip1) serine protease. Hip1 is a cell-envelope-associated enzyme with minimal homology to host proteases, making it an ideal target for probe development. We identified substituted 7-amino-4-chloro-3-(2-bromoethoxy)isocoumarins as irreversible inhibitor scaffolds. Furthermore, we used specificity data to generate selective reporter substrates and to further optimize a selective chloroisocoumarin inhibitor. These new reagents are potentially useful in delineating the roles of Hip1 during pathogenesis or as diagnostic imaging tools for specifically monitoring Mtb infections. PMID:27739665

  8. Potential Role for Mycobacterium tuberculosis Specific IL-2 and IFN-γ Responses in Discriminating between Latent Infection and Active Disease after Long-Term Stimulation

    PubMed Central

    Sun, Qin; Wei, Wei; Sha, Wei

    2016-01-01

    Interferon gamma release assays (IGRAs) could accurately diagnose Mycobacterium tuberculosis (M.tuberculosis) infection. However, these assays do not discriminate between latent tuberculosis infection (LTBI) and active tuberculosis disease (ATB). Here, a total of 177 subjects, including 65 patients with ATB, 43 subjects with LTBI, and 69 TB-uninfected controls (CON group) were enrolled. The concentration of IFN-γ, IP-10, and IL-2 was determined in peripheral blood mononuclear cells (PBMCs) after short-term (24h) or long-term (72h) stimulation with TB antigens including ESAT-6/CFP-10 (EC) and purified protein derivative (PPD).EC-stimulated IL-2 and gamma interferon-inducible protein 10 (IP-10) release (24h and 72h) showed a good diagnostic performance in distinguishing between TB-infected and TB-uninfected individuals, but failed to discriminate between ATB and LTBI. After 72h of incubation, the release of IL-2 was higher in LTBI patients after stimulation with EC and PPD. The PPD-stimulated IL-2/IFN-γ ratio after 72h incubation had the diagnostic potential to discriminate between ATB and LTBI, with a sensitivity of 90.8% and a specificity of 97.7%. In addition, these new biomarkers, combined with T-SPOT test in a two-step strategy, were validated with high levels of accuracy in a prospective clinical-based cohort. Collectively, the PPD-stimulated IL-2/IFN-γ ratio after long-term incubation may be an alternative diagnostic biomarker in distinguishing between active TB patients and subjects with latent infection. PMID:28033330

  9. Rapid diagnosis of Mycobacterium tuberculosis bacteremia by PCR.

    PubMed Central

    Folgueira, L; Delgado, R; Palenque, E; Aguado, J M; Noriega, A R

    1996-01-01

    A method based on DNA amplification and hybridization has been used for the rapid detection of Mycobacterium tuberculosis in blood samples from 38 hospitalized patients (15 human immunodeficiency virus [HIV] positive and 23 HIV negative) in whom localized or disseminated forms of tuberculosis were suspected. In 32 of these patients, the diagnosis of tuberculosis was eventually confirmed by conventional bacteriological or histological procedures. M. tuberculosis DNA was detected with the PCR technique in the peripheral blood mononuclear cells from 9 of 11 (82%) HIV-infected patients and in 7 of 21 (33%) HIV-negative patients (P < 0.01), while M. tuberculosis blood cultures were positive in 1 of 8 (12.5%) and 1 of 18 (5.5%) patients, respectively. PCR was positive in all cases with disseminated disease in both HIV-negative and HIV-positive patients and also in the HIV-positive patients with extrapulmonary tuberculosis. Seven samples from patients with documented illness other than tuberculosis and 12 specimens from healthy volunteers, including seven volunteers with a recent positive purified protein derivative test, were used as controls and had a negative PCR. These results suggest that detection of M. tuberculosis DNA in peripheral blood mononuclear cells may be a useful tool for rapid diagnosis of disseminated and extrapulmonary forms of tuberculosis, especially in an HIV-positive population. PMID:8904404

  10. Qualitative Evaluation of a Text Messaging Intervention to Support Patients With Active Tuberculosis: Implementation Considerations

    PubMed Central

    Sward, Katherine A; Beck, Susan L; Pearce, Patricia F; Thurston, Diana; Chirico, Cristina

    2015-01-01

    Background Tuberculosis (TB) remains a major global public health problem and mobile health (mHealth) interventions have been identified as a modality to improve TB outcomes. TextTB, an interactive text-based intervention to promote adherence with TB medication, was pilot-tested in Argentina with results supporting the implementation of trials at a larger scale. Objective The objective of this research was to understand issues encountered during pilot-testing in order to inform future implementation in a larger-scale trial. Methods A descriptive, observational qualitative design guided by a sociotechnical framework was used. The setting was a clinic within a public pulmonary-specialized hospital in Argentina. Data were collected through workflow observation over 115 days, text messages (n=2286), review of the study log, and stakeholder input. Emerging issues were categorized as organizational, human, technical, or sociotechnical considerations. Results Issues related to the intervention included workflow issues (eg, human, training, security), technical challenges (eg, data errors, platform shortcomings), and message delivery issues (eg, unintentional sending of multiple messages, auto-confirmation problems). System/contextual issues included variable mobile network coverage, electrical and Internet outages, and medication shortages. Conclusions Intervention challenges were largely manageable during pilot-testing, but need to be addressed systematically before proceeding with a larger-scale trial. Potential solutions are outlined. Findings may help others considering implementing an mHealth intervention to anticipate and mitigate certain challenges. Although some of the issues may be context dependent, other issues such as electrical/Internet outages and limited resources are not unique issues to our setting. Release of new software versions did not result in solutions for certain issues, as specific features used were removed. Therefore, other software options

  11. Tuberculosis Treatment Completion Rates in Southern New Mexico Colonias.

    PubMed

    Holden, Maria Arroyo; Huttlinger, Kathleen; Schultz, Pamela; Mullins, Iris; Forster-Cox, Sue

    2016-04-01

    TB medication completion treatment rates for active TB patients living in impoverished US-Mexico border communities called colonias in southern New Mexico counties are unknown. It might be suspected that residents of colonias have lower completion rates than those living in incorporated and medically more accessible areas. A retrospective record review of closed TB case records from 1993 to 2010 of southern New Mexico border counties, was conducted using a modified version of the New Mexico Department of Health Tuberculosis Targeted Health Assessment/History form (Appendix 1). Study findings reveal that despite their unincorporated status, poorer living conditions and questionable legal status, colonia TB patients had a higher medication completion rate than their non-colonia counterparts. A robust New Mexico TB treatment program contributed to high completion rates with death being the number-one reason for treatment non-completion in both colonia and non-colonias.

  12. Rate of tuberculosis infection in children and adolescents with household contact with adults with active pulmonary tuberculosis as assessed by tuberculin skin test and interferon-gamma release assays.

    PubMed

    Ferrarini, M A G; Spina, F G; Weckx, L Y; Lederman, H M; De Moraes-Pinto, M I

    2016-03-01

    Tuberculosis (TB) infection was evaluated in Brazilian immunocompetent children and adolescents exposed and unexposed (control group) to adults with active pulmonary TB. Both groups were analysed by clinical and radiological assessment, TST, QFT-IT and T-SPOT.TB. The three tests were repeated after 8 weeks in the TB-exposed group if results were initially negative. Individuals with latent tuberculosis infection (LTBI) were treated and tests were repeated after treatment. Fifty-nine TB-exposed and 42 controls were evaluated. Rate of infection was 69·5% and 9·5% for the exposed and control groups, respectively. The exposed group infection rate was 61% assessed by TST, 57·6% by T-SPOT.TB, and 59·3%, by QFT-IT. No active TB was diagnosed. Agreement between the three tests was 83·1% and 92·8% in the exposed and control groups, respectively. In the exposed group, T-SPOT.TB added four TB diagnoses [16%, 95% confidence interval (CI) 1·6-30·4] and QFT-IT added three TB diagnoses (12%, 95% CI 0-24·7) in 25 individuals with negative tuberculin skin test (TST). Risk factors associated to TB infection were contact with an adult with active TB [0-60 days: odds ratio (OR) 6·9; >60 days: OR 27·0] and sleeping in the same room as an adult with active TB (OR 5·2). In Brazilian immunocompetent children and adolescents, TST had a similar performance to interferon-gamma release assays and detected a high rate of LTBI.

  13. New tools for detecting latent tuberculosis infection: evaluation of RD1-specific long-term response

    PubMed Central

    2009-01-01

    Background Interferon-gamma (IFN-γ) release assays (IGRAs) were designed to detect latent tuberculosis infection (LTBI). However, discrepancies were found between the tuberculin skin test (TST) and IGRAs results that cannot be attributed to prior Bacille Calmètte Guerin vaccinations. The aim of this study was to evaluate tools for improving LTBI diagnosis by analyzing the IFN-γ response to RD1 proteins in prolonged (long-term response) whole blood tests in those subjects resulting negative to assays such as QuantiFERON-TB Gold In tube (QFT-IT). Methods The study population included 106 healthy TST+ individuals with suspected LTBI (recent contact of smear-positive TB and homeless) consecutively enrolled. As controls, 13 healthy subjects unexposed to M. tuberculosis (TST-, QFT-IT-) and 29 subjects with cured pulmonary TB were enrolled. IFN-γ whole blood response to RD1 proteins and QFT-IT were evaluated at day 1 post-culture. A prolonged test evaluating long-term IFN-γ response (7-day) to RD1 proteins in diluted whole blood was performed. Results Among the enrolled TST+ subjects with suspected LTBI, 70/106 (66.0%) responded to QFT-IT and 64/106 (60.3%) to RD1 proteins at day 1. To evaluate whether a prolonged test could improve the detection of LTBI, we set up the test using cured TB patients (with a microbiologically diagnosed past pulmonary disease) who resulted QFT-IT-negative and healthy controls as comparator groups. Using this assay, a statistically significant difference was found between IFN-γ levels in cured TB patients compared to healthy controls (p < 0.006). Based on these data, we constructed a receiver operating characteristic (ROC) curve and we calculated a cut-off. Based on the cut-off value, we found that among the 36 enrolled TST+ subjects with suspected LTBI not responding to QFT-IT, a long term response to RD1 proteins was detected in 11 subjects (30.6%). Conclusion These results indicate that IFN-γ long-term response to M. tuberculosis RD1

  14. Active Site Loop Dynamics of a Class IIa Fructose 1,6-Bisphosphate Aldolase from Mycobacterium tuberculosis

    SciTech Connect

    Pegan, Scott D.; Rukseree, Kamolchanok; Capodagli, Glenn C.; Baker, Erica A.; Krasnykh, Olga; Franzblau, Scott G.; Mesecar, Andrew D.

    2013-01-08

    The class II fructose 1,6-bisphosphate aldolases (FBAs, EC 4.1.2.13) comprises one of two families of aldolases. Instead of forming a Schiff base intermediate using an ε-amino group of a lysine side chain, class II FBAs utilize Zn(II) to stabilize a proposed hydroxyenolate intermediate (HEI) in the reversible cleavage of fructose 1,6-bisphosphate, forming glyceraldehyde 3-phosphate and dihydroxyacetone phosphate (DHAP). As class II FBAs have been shown to be essential in pathogenic bacteria, focus has been placed on these enzymes as potential antibacterial targets. Although structural studies of class II FBAs from Mycobacterium tuberculosis (MtFBA), other bacteria, and protozoa have been reported, the structure of the active site loop responsible for catalyzing the protonation–deprotonation steps of the reaction for class II FBAs has not yet been observed. We therefore utilized the potent class II FBA inhibitor phosphoglycolohydroxamate (PGH) as a mimic of the HEI- and DHAP-bound form of the enzyme and determined the X-ray structure of the MtFBA–PGH complex to 1.58 Å. Remarkably, we are able to observe well-defined electron density for the previously elusive active site loop of MtFBA trapped in a catalytically competent orientation. Utilization of this structural information and site-directed mutagenesis and kinetic studies conducted on a series of residues within the active site loop revealed that E169 facilitates a water-mediated deprotonation–protonation step of the MtFBA reaction mechanism. Furthermore, solvent isotope effects on MtFBA and catalytically relevant mutants were used to probe the effect of loop flexibility on catalytic efficiency. Additionally, we also reveal the structure of MtFBA in its holoenzyme form.

  15. Tuberculosis in neonates and infants: epidemiology, pathogenesis, clinical manifestations, diagnosis, and management issues.

    PubMed

    Skevaki, Chrysanthi L; Kafetzis, Dimitrios A

    2005-01-01

    Tuberculosis is one of the leading infectious causes of death and as such represents a major global health problem. Infants may develop congenital tuberculosis from an infectious mother or, most commonly, they may acquire postnatal disease by contact with an infectious adult source. Important epidemiologic, pathogenetic, and clinical data regarding the management of infantile disease are reviewed. Diagnostic evaluation includes tuberculin skin tests, chest radiography and other imaging studies, smears and cultures, examination of the cerebrospinal fluid, and polymerase chain reaction, as well as the more recent interferon-gamma assay. Pregnant women with a positive Mantoux skin test but normal chest x-ray should either start chemoprophylaxis during gestation or after delivery depending on the likelihood of being recently infected, their risk of progression to disease, as well as their clinical evidence of disease. Pregnant women with a positive Mantoux skin test and chest x-ray or symptoms indicative of active disease should be treated with non-teratogenic agents during gestation; all household contacts should also be screened. When tuberculosis is suspected around delivery, the mother should be assessed by chest x-ray and sputum smear; separation of mother and offspring is indicated only if the mother is non-adherent to medical treatment, needs to be hospitalized, or when drug-resistant tuberculosis is involved. According to the American Academy of Pediatrics, treatment of latent infection is highly effective with isoniazid administration for 9 months. This regimen may be extended to 12 months for immunocompromised patients. When drug resistance is suspected, combination therapies, which usually consist of isoniazid with rifampin (rifampicin), are administered until the results of susceptibility tests become available. Organisms resistant to isoniazid only may be treated with rifampin alone for a total of 6-9 months. All infants with tuberculosis disease should be

  16. [Tuberculosis after renal transplantation].

    PubMed

    Korzeniewska, Anna; Dyła, Tomasz; Kosacka, Monika; Jankowska, Renata

    2009-01-01

    Renal transplant recipients carry a relatively high risk of developing tuberculosis (TB). In most cases, active TB is the result of reactivation of a latent infection and is located in the lungs. In these patients, clinical presentation of TB can often be atypical and there is a high risk of dissemination and high mortality rates. Therefore, the use of invasive procedures for proper diagnosis is recommended, as well as anti-tuberculosis therapy instituted whenever there is a strong suspicion of TB on clinical grounds, even without microbiological evidence. The treatment of active TB in renal transplant recipients should be the same as in the general population. To avoid graft rejection, blood levels of calcineurin inhibitors should be monitored closely. Prophylaxis is recommended for high-risk patients.

  17. Rare Offshoot of a Common Malady Anaemia and Tuberculosis.

    PubMed

    Kolla, Gautham; Acharya, Vishak; Balanthimogru, Prashantha; Mani, Arun; Ruman, Shehzad

    2016-08-01

    Haematological manifestations are one of the rarer presentations of tuberculosis and are usually of normocytic normochromic type. An association of Autoimmune Haemolytic Anaemia (AIHA) with active pulmonary tuberculosis is an exceeding rare entity, though anaemia and tuberculosis commonly co-exist. We report a patient with sputum negative pulmonary tuberculosis with associated Coomb's positive AIHA. The patient responded well to Anti- Tubercular Therapy (ATT) and low dose steroids tapered over a month.

  18. Rare Offshoot of a Common Malady Anaemia and Tuberculosis

    PubMed Central

    Acharya, Vishak; Balanthimogru, Prashantha; Mani, Arun; Ruman, Shehzad

    2016-01-01

    Haematological manifestations are one of the rarer presentations of tuberculosis and are usually of normocytic normochromic type. An association of Autoimmune Haemolytic Anaemia (AIHA) with active pulmonary tuberculosis is an exceeding rare entity, though anaemia and tuberculosis commonly co-exist. We report a patient with sputum negative pulmonary tuberculosis with associated Coomb’s positive AIHA. The patient responded well to Anti- Tubercular Therapy (ATT) and low dose steroids tapered over a month. PMID:27656489

  19. System and method for disrupting suspect objects

    SciTech Connect

    Gladwell, T. Scott; Garretson, Justin R; Hobart, Clinton G; Monda, Mark J

    2013-07-09

    A system and method for disrupting at least one component of a suspect object is provided. The system includes a source for passing radiation through the suspect object, a screen for receiving the radiation passing through the suspect object and generating at least one image therefrom, a weapon having a discharge deployable therefrom, and a targeting unit. The targeting unit displays the image(s) of the suspect object and aims the weapon at a disruption point on the displayed image such that the weapon may be positioned to deploy the discharge at the disruption point whereby the suspect object is disabled.

  20. A species-specific nucleotide sequence of Mycobacterium tuberculosis encodes a protein that exhibits hemolytic activity when expressed in Escherichia coli.

    PubMed Central

    Leão, S C; Rocha, C L; Murillo, L A; Parra, C A; Patarroyo, M E

    1995-01-01

    Species-specific proteins may be implicated in the unique pathogenic mechanisms characteristic of Mycobacterium tuberculosis. In previous studies, a 3.0-kb species-specific DNA fragment of M. tuberculosis was identified (C. A. Parra, L. P. Londoño, P. del Portillo, and M. E. Patarroyo, Immun. 59:3411-3417, 1991). The nucleotide sequence of this 3.0-kb fragment has been obtained. This sequence was shown to contain two open reading frames (ORFs) whose putative gene products share 68.9% identity between each other. The major ORF shows 57.8% similarity with PLC-N and 53.2% similarity with PLC-H, two phospholipase C enzymes from Pseudomonas aeruginosa. The major ORF was amplified by PCR and cloned into the pGEX-5T expression vector. Cell extracts of Escherichia coli overexpressing this glutathione S-transferase fusion protein were shown to produce beta-hemolysis suggestive of phospholipase activity. Since phospholipase C enzymes have been reported as virulence factors of P. aeruginosa and also of the intracellular pathogen Listeria monocytogenes, it is possible that the proteins identified in this study could also play a role in sustaining tuberculosis infection in humans. PMID:7591062

  1. Dimerization of inositol monophosphatase Mycobacterium tuberculosis SuhB is not constitutive, but induced by binding of the activator Mg2+

    PubMed Central

    Brown, Alistair K; Meng, Guoyu; Ghadbane, Hemza; Scott, David J; Dover, Lynn G; Nigou, Jérôme; Besra, Gurdyal S; Fütterer, Klaus

    2007-01-01

    Background The cell wall of Mycobacterium tuberculosis contains a wide range of phosphatidyl inositol-based glycolipids that play critical structural roles and, in part, govern pathogen-host interactions. Synthesis of phosphatidyl inositol is dependent on free myo-inositol, generated through dephosphorylation of myo-inositol-1-phosphate by inositol monophosphatase (IMPase). Human IMPase, the putative target of lithium therapy, has been studied extensively, but the function of four IMPase-like genes in M. tuberculosis is unclear. Results We determined the crystal structure, to 2.6 Å resolution, of the IMPase M. tuberculosis SuhB in the apo form, and analysed self-assembly by analytical ultracentrifugation. Contrary to the paradigm of constitutive dimerization of IMPases, SuhB is predominantly monomeric in the absence of the physiological activator Mg2+, in spite of a conserved fold and apparent dimerization in the crystal. However, Mg2+ concentrations that result in enzymatic activation of SuhB decisively promote dimerization, with the inhibitor Li+ amplifying the effect of Mg2+, but failing to induce dimerization on its own. Conclusion The correlation of Mg2+-driven enzymatic activity with dimerization suggests that catalytic activity is linked to the dimer form. Current models of lithium inhibition of IMPases posit that Li+ competes for one of three catalytic Mg2+ sites in the active site, stabilized by a mobile loop at the dimer interface. Our data suggest that Mg2+/Li+-induced ordering of this loop may promote dimerization by expanding the dimer interface of SuhB. The dynamic nature of the monomer-dimer equilibrium may also explain the extended concentration range over which Mg2+ maintains SuhB activity. PMID:17725819

  2. [Design and study of new agents having antitubercular activity: the original compound perchlosone as a potent agent of etiotropic therapy for tuberculosis].

    PubMed

    Vinogradova, T I; Aleksandrova, A E; Antonenkova, E V; Elokhina, V N; Nakhmanovich, A S

    1999-01-01

    Studies dealing with the design of new antituberculous agents based on goal-oriented synthesis have provided the agent Perchlosone which is similar to isoniazid and rifampicin, produces in tuberculostatic activity against sensitive laboratory cultured mycobacteria, produces an inhibitory action on polyresistant clinical strains. Experiments on animals (mice, rabbits) with experimental tuberculosis have established that Perchlosone and isoniazid have equal therapeutical properties, and the former shows a synergist interaction with rifampicin, has neither mutagenic activity nor negative effects on immunity and the surfactant system of the lung.

  3. Costs and Consequences of Using Interferon-γ Release Assays for the Diagnosis of Active Tuberculosis in India

    PubMed Central

    Little, Kristen M.; Pai, Madhukar; Dowdy, David W.

    2015-01-01

    Background There is growing concern that interferon-γ release assays (IGRAs) are being used off-label for the diagnosis of active tuberculosis (TB) disease in many high-burden settings, including India, where the background prevalence of latent TB infection is high. We analyzed the costs and consequences of using IGRAs for the diagnosis of active TB in India from the perspective of the Indian TB control sector. Methods and Findings We constructed a decision analytic model to estimate the incremental cost and effectiveness of IGRAs for the diagnosis of active TB in India. We compared a reference scenario of clinical examination and non-microbiological tests against scenarios in which clinical diagnosis was augmented by the addition of either sputum smear microscopy, IGRA, or Xpert MTB/RIF. We examined costs (in 2013 US dollars) and consequences from the perspective of the Indian healthcare sector. Relative to sputum smear microscopy, use of IGRA for active TB resulted in 23,700 (95% uncertainty range, UR: 3,800 – 38,300) additional true-positive diagnoses, but at the expense of 315,700 (95% UR: 118,300 – 388,400) additional false-positive diagnoses and an incremental cost of US$49.3 million (95% UR: $34.9 – $58.0 million) (2.9 billion Indian Rupees). Relative to Xpert MTB/RIF (including the cost of treatment for drug resistant TB), use of IGRA led to 400 additional TB cases treated (95% UR: [-8,000] – 16,200), 370,600 (95% UR: 252,200 – 441,700) more false-positive diagnoses, 70,400 (95% UR: [-7,900] – 247,200) fewer disability-adjusted life years averted, and US$14.6 million (95%UR: [-$7.2] – $28.7 million) (854 million Indian Rupees) in additional costs. Conclusion Using IGRAs for diagnosis of active TB in a setting like India results in tremendous overtreatment of people without TB, and substantial incremental cost with little gain in health. These results support the policies by WHO and Standards for TB Care in India, which discourage the use of

  4. Using Peer Helpers for Tuberculosis Prevention.

    ERIC Educational Resources Information Center

    McCue, Maureen; Afifi, Larry Anna

    1996-01-01

    Describes a peer helper program initiated by the University of Iowa Student Health Services to prevent active tuberculosis development among foreign national students. Before instituting the program, compliance with tuberculosis prevention efforts for those students was less than 5%. Since the peer program was instituted, compliance has risen to…

  5. Abdominal tuberculosis.

    PubMed Central

    Kapoor, V. K.

    1998-01-01

    Tuberculosis has staged a global comeback and forms a dangerous combination with AIDS. The abdomen is one of the common sites of extrapulmonary involvement. Patients with abdominal tuberculosis have a wide range and spectrum of symptoms and signs; the disease is therefore a great mimic. Diagnosis, mainly radiological and supported by endoscopy, is difficult to make and laparotomy is required in a large number of patient. Management involves judicious combination of antitubercular therapy and surgery which may be required to treat complications such as intestinal obstruction and perforation. The disease, though potentially curable, carries a significant morbidity and mortality. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 PMID:9926119

  6. [Tuberculosis, today].

    PubMed

    Scala, Raffaele

    2012-06-01

    Tuberculosis is still a major health and social problem because, on the one hand, we have witnessed the dismantling of the sanatoriums, with a reduced level of diagnostic suspicion, knowledge and expertise on the management of the disease, while, the other side, are considered migratory flows, the lower socio-economic faced by immigrants, the states of immunosuppression associated with HIV prevalence of malnutrition and other diseases, and the phenomenon of multidrug-resistance, which often turns out to be iatrogenic. The success of the strategy of control/elimination of tuberculosis promoted by the World Health Organization requires a well coordinated multidisciplinary approach in which everyone does their part, the general practitioner, the pulmonologist, the infectious disease specialist, and the microbiologist.

  7. Tracheobronchial tuberculosis

    PubMed Central

    Pathak, Vikas; Shepherd, Ray W.

    2016-01-01

    Tracheobronchial tuberculosis (TBTB) is reported in approximately 10% to 39% of the patients with pulmonary tuberculosis. It is defined as the tubercle infection of the trachea and or bronchi. Due to its non-specific presentation, insidious onset and normal chest radiography in about 10–20% of the patients, the diagnosis is delayed. Bronchoscopy is the most definite method of diagnosis which provides adequate specimens for microbiological and histopathological diagnosis. Tracheobronchial stenosis is one of the most common long term complications of TBTB resulting in significant morbidity. It is estimated that 90% of patients with TBTB have some degree of tracheal and or bronchial stenosis. In this review article, we will discuss the pathogenesis, symptoms, imaging, bronchoscopic findings, and treatment of TBTB and management of tracheobronchial stenosis. PMID:28149582

  8. Photometry of 50 suspected variable stars

    NASA Technical Reports Server (NTRS)

    Hooten, James T.; Hall, Douglas S.

    1990-01-01

    Fifty stars have been chosen as suspected variable stars and analyzed for variability. A large portion of this sample are stars that are either proved active chromosphere stars or are candidates for such activity. The photometric data base consists of differential V measurements of the Vanderbilt 16 inch (41 cm) automatic photoelectric telescope and 25 observers at 26 observatories worldwide. Published photometric data have also been utilized, with proper adjustments made to ensure that all magnitudes are differential. Searches for photometric period, amplitudes, and times of minimum light showed 68 percent of the sample to be photometrically variable with periods found for 34. Two stars were deemed norvariable for the period of observation. Conclusive statements could not be made concerning the photometric variability of the 14 remaining stars.

  9. Systematic expression profiling analysis mines dys-regulated modules in active tuberculosis based on re-weighted protein-protein interaction network and attract algorithm.

    PubMed

    Sun, Ying; Weng, Yan; Zhang, Ying; Yan, Xiang; Guo, Lei; Wang, Jia; Song, Xin; Yuan, Ying; Chang, Fu-Ye; Wang, Chun-Ling

    2017-03-18

    About 90% of tuberculosis (TB) patients latently infected with Mycobacterium tuberculosis (Mtb) show no symptoms, yet have a 10% chance in lifetime to progress active TB. Nevertheless, current diagnosis approaches need improvement in efficiency and sensitivity. The objective of this work was to detect potential signatures for active TB to further improve the understanding of the biological roles of functional modules involved in this disease. First, targeted networks of active TB and control groups were established via re-weighting protein-protein interaction (PPI) networks using Pearson's correlation coefficient (PCC). Candidate modules were detected from the targeted networks, and the modules with Jaccard score >0.7 were defined as attractors. After that, identification of dys-regulated modules was conducted from the attractors using attract method, Subsequently, gene oncology (GO) enrichment analyses were implemented for genes in the dys-regulated modules. We obtained 33 and 65 candidate modules from the targeted networks of control and active TB groups, respectively. Overall, 13 attractors were identified. Using the cut-off criteria of false discovery rate <0.05, there were 4 dys-regulated modules (Module 1, 2, 3, and 4). Based on the GO annotation results, genes in Modules 1, 2 and 4 were only involved in translation. Most genes in Module 1, 2 and 4 were associated with ribosomes. Accordingly, these dys-regulated modules might serve as potential biomarkers of active TB, facilitating the development for a more efficient, and sensitive diagnostic assay for active TB.

  10. Performance of a lateral flow immunochromatography test for the rapid diagnosis of active tuberculosis in a large multicentre study in areas with different clinical settings and tuberculosis exposure levels

    PubMed Central

    Manga, Selene; Perales, Rocio; Reaño, Maria; D’Ambrosio, Lia

    2016-01-01

    Background Tuberculosis (TB) continues to cause an outsized burden of morbidity and mortality worldwide, still missing efficient and largely accessible diagnostic tools determining an appropriate control of the disease. Serological tests have the potentially to impact TB diagnosis, in particular in extreme clinical settings. Methods The diagnostic performances of the TB-XT HEMA EXPRESS (HEMA-EXPRESS) immunochromatographic rapid test for active TB diagnosis, based on use of multiple Mycobacterium tuberculosis (MTB) specific antigens, have been evaluated in a large study multicentre TB case-finding study, in populations with different exposure level to TB. A total of 1,386 subjects were enrolled in the six participating centres in Peru: 290 active-TB and 1,096 unaffected subjects. Results The TB prevalence (overall 20.5%) varied between 4.0% and 41.1% in the different study groups. Overall, the HEMA-EXPRESS test had 30.6% sensitivity (range 3.9–77.9%) and 84.6% specificity (range 51.6–97.3%). A significant inverse correlation between test accuracy (overall 73.5%, range 40.4–96.4%) and TB prevalence in the various study populations was observed (Pearson’s r=−0.7985; P=0.05). Conclusions HEMA-EXPRESS, is rapid and relatively inexpensive test suitable for routine use in TB diagnosis. In low TB prevalence conditions, test performance appears in line with WHO Target Product Profile for TB diagnostics. Performances appear suboptimal in high TB prevalence settings. Appropriate set-up in operative clinical settings has to be considered for novel serological tests for TB diagnosis, particularly for formats suitable for point-of-care use. PMID:28066611

  11. Thiolates Chemically Induce Redox Activation of BTZ043 and Related Potent Nitro Aromatic Anti-Tuberculosis Agents

    PubMed Central

    Tiwari, Rohit; Moraski, Garrett C.; Krchňák, Viktor; Miller, Patricia A.; Colon-Martinez, Mariangelli; Herrero, Eliza; Oliver, Allen G.; Miller, Marvin J.

    2013-01-01

    The development of multidrug resistant (MDR) and extensively drug resistant (XDR) forms of tuberculosis (TB) has stimulated research efforts globally to expand the new drug pipeline. Nitro aromatic compounds, including 1, 3-Benzothiazin-4-ones (BTZs) and related agents, are a promising new class for the treatment of TB. Research has shown that the nitroso intermediates of BTZs that are generated in vivo cause suicide inhibition of decaprenylphosphoryl-β-D-ribose 2′ oxidase (DprE1), which is responsible for cell wall arabinogalactan biosynthesis. We have designed and synthesized novel anti-TB agents inspired from BTZs and other nitroaromatic compounds. Computational studies indicated that the unsubstituted aromatic carbons of BTZ043 and related nitroaromatic compounds are the most electron deficient and might be prone to nucleophilic attack. Our chemical studies on BTZ043 and the additional nitro aromatic compounds synthesized by us and the others confirmed the postulated reactivity. The results indicate that nucleophiles such as thiolates, cyanide and hydride induce non-enzymatic reduction of the nitro groups present in these compounds to the corresponding nitroso intermediates by addition at the unsubstituted electron deficient aromatic carbon present in these compounds. Furthermore we demonstrate here that these compounds are good candidates for the classical von Richter reaction. These chemical studies offer an alternate hypotheses for the mechanism of action of nitro aromatic anti-TB agents in that the cysteine thiol(ate) or a hydride source at the active site of DprE1 may trigger the reduction of the nitro groups in a manner similar to the von Richter reaction to the nitroso intermediates, to initiate the inhibition of DprE1. PMID:23402278

  12. First-in-Class Inhibitors of Sulfur Metabolism with Bactericidal Activity against Non-Replicating M. tuberculosis

    PubMed Central

    Palde, Prakash B.; Bhaskar, Ashima; Pedrό Rosa, Laura E.; Madoux, Franck; Chase, Peter; Gupta, Vinayak; Spicer, Timothy; Scampavia, Louis; Singh, Amit; Carroll, Kate S.

    2016-01-01

    Development of effective therapies to eradicate persistent, slowly replicating M. tuberculosis (Mtb) represents a significant challenge to controlling the global TB epidemic. To develop such therapies, it is imperative to translate information from metabolome and proteome adaptations of persistent Mtb into the drug discovery screening platforms. To this end, reductive sulfur metabolism is genetically and pharmacologically implicated in survival, pathogenesis, and redox homeostasis of persistent Mtb. Therefore, inhibitors of this pathway are expected to serve as powerful tools in its preclinical and clinical validation as a therapeutic target for eradicating persisters. Here, we establish a first functional HTS platform for identification of APS reductase (APSR) inhibitors, a critical enzyme in the assimilation of sulfate for the biosynthesis of cysteine and other essential sulfur-containing molecules. Our HTS campaign involving 38 350 compounds led to the discovery of three distinct structural classes of APSR inhibitors. A class of bioactive compounds with known pharmacology displayed potent bactericidal activity in wild-type Mtb as well as MDR and XDR clinical isolates. Top compounds showed markedly diminished potency in a conditional ΔAPSR mutant, which could be restored by complementation with Mtb APSR. Furthermore, ITC studies on representative compounds provided evidence for direct engagement of the APSR target. Finally, potent APSR inhibitors significantly decreased the cellular levels of key reduced sulfur-containing metabolites and also induced an oxidative shift in mycothiol redox potential of live Mtb, thus providing functional validation of our screening data. In summary, we have identified first-in-class inhibitors of APSR that can serve as molecular probes in unraveling the links between Mtb persistence, antibiotic tolerance, and sulfate assimilation, in addition to their potential therapeutic value. PMID:26524379

  13. Tuberculosis (For Parents)

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old Tuberculosis KidsHealth > For Parents > Tuberculosis A A A What's in this article? Signs ... When to You Call the Doctor en español Tuberculosis Tuberculosis (popularly known as "TB") is a disease ...

  14. Tuberculosis (For Parents)

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old Tuberculosis KidsHealth > For Parents > Tuberculosis Print A A A What's in this article? ... When to You Call the Doctor en español Tuberculosis Tuberculosis (popularly known as "TB") is a disease ...

  15. Hospital management of tuberculosis in a region with a low incidence of tuberculosis and a high prevalence of nontuberculous mycobacteria.

    PubMed

    Alexander, B D; Stout, J E; Reller, L B; Hamilton, C D

    2001-11-01

    We prospectively assessed the management of patients with suspected tuberculosis (TB) in an area with a high prevalence of nontuberculous mycobacteria (NTM) and a low incidence of TB. Clinicians' assessments were sensitive for TB but had poor predictive value. The acid-fast smear was a weak predictor of TB, owing to a high rate of isolation of NTM.

  16. Preliminary structure-activity relationships and biological evaluation of novel antitubercular indolecarboxamide derivatives against drug-susceptible and drug-resistant Mycobacterium tuberculosis strains.

    PubMed

    Onajole, Oluseye K; Pieroni, Marco; Tipparaju, Suresh K; Lun, Shichun; Stec, Jozef; Chen, Gang; Gunosewoyo, Hendra; Guo, Haidan; Ammerman, Nicole C; Bishai, William R; Kozikowski, Alan P

    2013-05-23

    Tuberculosis (TB) remains one of the leading causes of mortality and morbidity worldwide, with approximately one-third of the world's population infected with latent TB. This is further aggravated by HIV coinfection and the emergence of multidrug- and extensively drug-resistant (MDR and XDR, respectively) TB; hence the quest for highly effective antitubercular drugs with novel modes of action is imperative. We report herein the discovery of an indole-2-carboxamide analogue, 3, as a highly potent antitubercular agent, and the subsequent chemical modifications aimed at establishing a preliminary body of structure-activity relationships (SARs). These efforts led to the identification of three molecules (12-14) possessing an exceptional activity in the low nanomolar range against actively replicating Mycobacterium tuberculosis , with minimum inhibitory concentration (MIC) values lower than those of the most prominent antitubercular agents currently in use. These compounds were also devoid of apparent toxicity to Vero cells. Importantly, compound 12 was found to be active against the tested XDR-TB strains and orally active in the serum inhibition titration assay.

  17. Perspectives on the development of novel potentially active quinolones against tuberculosis and cancer.

    PubMed

    Facchinetti, V; Gomes, C R B; de Souza, M V N; Vasconcelos, T R A

    2012-08-01

    Quinolones and its derivatives comprise an important group of heterocyclic compounds that exhibit a wide range of pharmacological properties such as antibacterial, antitumor, antiviral, anti-ischemic, antiparasitic and anxiolytic. Persistent efforts have been made over the years to develop novel congeners with superior biological activities and minimal potential for undesirable side-effects. The present review aims to highlight some recent discoveries on the development of novel quinolone-based compounds with potential antitubercular and anticancer activity.

  18. Scrotal tuberculosis in adult patients: a 10-year clinical experience.

    PubMed

    Lee, Ing-Kit; Yang, Wen-Chou; Liu, Jien-Wei

    2007-10-01

    Twenty-nine adults (mean age, 59.9 +/- 13.5 years) with scrotal tuberculosis (TB) were retrospectively analyzed. The mean interval from emergence of symptoms suggestive of scrotal TB to diagnosis established was 142.44 +/- 227.66 days. Scrotal TB was initially suspected in only five (17.2%) patients, and infection caused by bacteria other than Mycobacterium tuberculosis (55.2%) was the leading presumptive diagnosis. Of 28 patients with chest radiographs available, 7 (25%) disclosed active pulmonary TB, and 9 (32.1%) showed a TB scar. All patients received anti-TB chemotherapy; 20 (69%) additionally underwent surgery. Pathologic examination of resected tissue at therapeutic surgery, biopsy, or polymerase chain reaction assay of urine led to rapid diagnosis of scrotal TB. Although evidence of scrotal TB was easily obtainable, the lack of alertness made clinicians avert from the appropriate diagnostic approaches and rendered a delayed diagnosis. Our report underscores the urgent need for improving clinicians' awareness of scrotal TB.

  19. Activity of rifapentine and its metabolite 25-O-desacetylrifapentine compared with rifampicin and rifabutin against Mycobacterium tuberculosis, Mycobacterium africanum, Mycobacterium bovis and M. bovis BCG.

    PubMed

    Rastogi, N; Goh, K S; Berchel, M; Bryskier, A

    2000-10-01

    The in vitro activity of rifapentine and its metabolite, 25-O:-desacetylrifapentine, as compared with that of rifampicin and rifabutin, was determined against Mycobacterium tuberculosis, Mycobacterium africanum, Mycobacterium bovis and M. bovis BCG. MICs were determined radiometrically and by the 1% proportional method using Middlebrook 7H11 agar. The bactericidal effect of the drugs was determined in parallel at selected concentrations. For drugsusceptible isolates of M. tuberculosis, the Bactec MICs of rifapentine and 25-O:-desacetylrifapentine were 0.03-0.06 mg/L and 0. 125-0.25 mg/L, respectively. Similar MICs were obtained for M. africanum (0.03-0.125 and 0.125-0.50 mg/L, respectively), and M. bovis (0.063-0.25 and 0.125-1.0 mg/L, respectively), but MICs were considerably lower for M. bovis BCG (0.008-0.063 mg/L for rifapentine and 0.016-0.125 mg/L for its metabolite). In general, MICs determined using 7H11 agar medium were usually one or two dilutions higher than those obtained using Bactec broth. When compared with rifampicin and rifabutin, the inhibitory activity of rifapentine for drug-susceptible isolates was roughly equal to that of rifabutin, and the inhibitory activity of 25-O:-desacetylrifapentine was comparable to that of rifampicin; however, rifapentine was somewhat more bactericidal than rifabutin at equal concentrations. Clinical isolates of M. tuberculosis with a high degree of resistance to rifampicin (MIC >/= 32 mg/L) were also highly resistant to rifabutin, rifapentine and 25-O:-desacetylrifapentine, although the MICs of rifabutin in this case were somewhat lower than the MICs of rifapentine.

  20. Primary Tuberculosis of Hand Soft Tissue

    PubMed Central

    Altaf Mir, Mohd; Ahmad, Imran; Yaseen, Mihd

    2016-01-01

    The musculoskeletal extrapulmonary tuberculosis is uncommon, the upper extremity tuberculosis is not common and the mycobacterial involvement of skin of hands and synovial sheath of tendons is rare. This prospective observational study was undertaken between August 2014 and December 2015 in a tertiary referral hospital. Patients attending with suspected primary tuberculosis of soft tissue of the hand were included. Anteroposterior and lateral radiographs of the hand, wrist and lung and MRI were undertaken. A diagnosis of tuberculosis was made based on histology, and positive culture for Mycobacterium. Split thickness skin grafting was done after excision of tubercular cutaneous ulcers of hand. Postoperatively patients were treated with home based anti-tubercular chemotherapy. Lesions of synovial sheath of tendons were excised. Splints or plaster slabs were used in all patients. There were 3 males and 2 females with a mean age of 44.75±6.61 years (19-48 years). Based on clinical suspicion, plain radiographs and MRI, there were 3 patients with involvement of synovial sheath of tendons and 2 patients with involvement of skin of hand. Tuberculosis was confirmed histologically and Mycobacterium bovis was confirmed microbiologically. The delayed diagnosis is often due to slow progression and numerous differential diagnoses, which often leads to complications. Early radical excision of the infected tissues combined with anti- tubercular multidrug therapy gives good functional results and prevents recurrence. PMID:27853698

  1. High Systemic Exposure of Pyrazinoic Acid Has Limited Antituberculosis Activity in Murine and Rabbit Models of Tuberculosis

    PubMed Central

    Tasneen, Rokeya; O'Brien, Paul; Sarathy, Jansy; Safi, Hassan; Pinn, Michael; Alland, David; Dartois, Véronique

    2016-01-01

    Pyrazinamide (PZA) is a prodrug requiring conversion to pyrazinoic acid (POA) by an amidase encoded by pncA for in vitro activity. Mutation of pncA is the most common cause of PZA resistance in clinical isolates. To determine whether the systemic delivery of POA or host-mediated conversion of PZA to POA could circumvent such resistance, we evaluated the efficacy of orally administered and host-derived POA in vivo. Dose-ranging plasma and intrapulmonary POA pharmacokinetics and the efficacy of oral POA or PZA treatment against PZA-susceptible tuberculosis were determined in BALB/c and C3HeB/FeJ mice. The activity of host-derived POA was assessed in rabbits infected with a pncA-null mutant and treated with PZA. Median plasma POA values for the area under the concentration-time curve from 0 h to infinity (AUC0–∞) were 139 to 222 μg·h/ml and 178 to 287 μg·h/ml after doses of PZA and POA of 150 mg/kg of body weight, respectively, in mice. Epithelial lining fluid POA concentrations in infected mice were comparable after POA and PZA administration. In chronically infected BALB/c mice, PZA at 150 mg/kg reduced lung CFU counts by >2 log10 after 4 weeks. POA was effective only at 450 mg/kg, which reduced lung CFU counts by ∼0.7 log10. POA had no demonstrable bactericidal activity in C3HeB/FeJ mice, nor did PZA administered to rabbits infected with a PZA-resistant mutant. Oral POA administration and host-mediated conversion of PZA to POA producing plasma POA exposures comparable to PZA administration was significantly less effective than PZA. These results suggest that the intrabacillary delivery of POA and that producing higher POA concentrations at the site of infection will be more effective strategies for maximizing POA efficacy. PMID:27139472

  2. Diagnostic value of an enzyme-linked immunospot assay for interferon-γ in genitourinary tuberculosis.

    PubMed

    Lai, Chih-Cheng; Tan, Che-Kim; Lin, Sheng-Hsiang; Liao, Chun-Hsing; Huang, Yu-Tsung; Wang, Cheng-Yi; Wang, Jen-Yu; Lin, Hen-I; Hsueh, Po-Ren

    2010-11-01

    The aim of this study was to evaluate the diagnostic performance of an enzyme-linked immunospot (ELISPOT) assay for interferon-γ in patients with suspected genitourinary tuberculosis (TB). A total of 30 patients with suspected genitourinary TB at the National Taiwan University Hospital, Taipei, Taiwan, were prospectively enrolled from January 2007 to December 2009, and 12 of whom had positive urine culture for Mycobacterium tuberculosis. Frequency and dysuria were the most common symptoms noted in 6 (50.0%) and 4 (33.3%) patients, respectively. Pyuria was the most common finding of urinalysis noted in 11 (91.7%) patients. Six (50.0%) patients had positive acid-fast stain in urine. Among the 30 patients, 13 patients had positive ELISPOT assay. Eleven patients with positive ELISPOT assay had culture-confirmed TB, and the remaining 2 patients without evidence of active TB had positive ELISPOT assay. The overall sensitivity, specificity, positive predictive value, and negative predictive value for genitourinary TB diagnosis by the ELISPOT assay were 91.7% (95% confidence interval [CI], 59.8-99.6%), 88.9% (95% CI, 63.9-98.1%), 84.6% (95% CI, 53.7-97.3%), and 94.1% (95% CI, 69.2-96.7%), respectively. In conclusion, ELISPOT assay can provide useful support in diagnosing genitourinary TB.

  3. A Novel in vitro Human Macrophage Model to Study the Persistence of Mycobacterium tuberculosis Using Vitamin D(3) and Retinoic Acid Activated THP-1 Macrophages.

    PubMed

    Estrella, Jaymie L; Kan-Sutton, Celestine; Gong, Xing; Rajagopalan, Malini; Lewis, Dorothy E; Hunter, Robert L; Eissa, N Tony; Jagannath, Chinnaswamy

    2011-01-01

    Mycobacterium tuberculosis (Mtb) replicates within the human macrophages and we investigated the activating effects of retinoic acid (RA) and vitamin D(3) (VD) on macrophages in relation to the viability of intracellular Mtb. A combination of these vitamins (RAVD) enhanced the levels of DC-SIGN and mannose receptors on THP-1 macrophages that increased mycobacterial uptake but inhibited the subsequent intracellular growth of Mtb by inducing reactive oxygen species and autophagy. RAVD also enhanced antigen presenting and chemotactic receptors on THPs suggesting an activated phenotype for RAVD activated THPs. RAVD mediated activation was also associated with a marked phenotypic change in Mtb infected THPs that fused with adjacent THPs to form multinucleated giant cells (MNGCs). Typically, MNGCs occurred over 30 days of in vitro culture and contained non-replicating persisting Mtb for more than 60 days in culture. Latent tuberculosis occurs in over a third of mankind and we propose that RAVD mediated induction of persistent Mtb within human macrophages provides a novel model to develop therapeutic approaches and investigate pathogenesis of latency.

  4. An Evaluation of Passive and Active Approaches to Improve Tuberculosis Notifications in Afghanistan

    PubMed Central

    Sanaie, A.; Nasrat, A.; Seddiq, M. K.; Mahmoodi, S. D.; Stevens, R. H.; Creswell, J.

    2016-01-01

    Background In Afghanistan, improving TB case detection remains challenging. In 2014, only half of the estimated incident TB cases were notified, and notifications have decreased since peaking in 2007. Active case finding has been increasingly considered to improve TB case notifications. While access to health services has improved in Afghanistan, it remains poor and many people seeking health services won’t receive proper care. Methods From October 2011 through December 2012 we conducted three separate case finding strategies in six provinces of Afghanistan and measured impact on TB case notification. Systematically screening cough among attendees at 47 health facilities, active household contact investigation of smear-positive index TB patients, and active screening at 15 camps for internally displaced people were conducted. We collected both intervention yield and official quarterly notification data. Additional TB notifications were calculated by comparing numbers of cases notified during the intervention with those notified before the intervention, then adjusting for secular trends in notification. Results We screened 2,022,127 people for TB symptoms during the intervention, tested 59,838 with smear microscopy and detected 5,046 people with smear-positive TB. Most cases (81.7%, 4,125) were identified in health facilities while nearly 20% were found through active case finding. A 56% increase in smear-positive TB notifications was observed between the baseline and intervention periods among the 47 health facilities, where cases detected by all three strategies were notified. Discussion While most people with TB are likely to be identified through health facility screening, there are many people who remain without a proper diagnosis if outreach is not attempted. This is especially true in places like Afghanistan where access to general services is poor. Targeted active case finding can improve the number of people who are detected and treated for TB and can

  5. Comparative antimycobacterial activities of rifampin, rifapentine, and KRM-1648 against a collection of rifampin-resistant Mycobacterium tuberculosis isolates with known rpoB mutations.

    PubMed Central

    Moghazeh, S L; Pan, X; Arain, T; Stover, C K; Musser, J M; Kreiswirth, B N

    1996-01-01

    A collection of 24 rifampin-resistant clinical isolates of Mycobacterium tuberculosis with characterized RNA polymerase beta-subunit (rpoB) gene mutations was tested against the antimycobacterial agents rifampin, rifapentine, and KRM-1648 to correlate levels of resistance with specific rpoB genotypes. The results indicate that KRM-1648 is more active in vitro than rifampin and rifapentine, and its ability to overcome rifampin resistance in strains with four different genetic alterations may prove to be useful in understanding structure-function relationships. PMID:8913484

  6. Autosomal recessive hyper IgM syndrome associated with activation-induced cytidine deaminase gene in three Turkish siblings presented with tuberculosis lymphadenitis - Case report.

    PubMed

    Patiroglu, Turkan; Akar, H Haluk; van der Burg, Mirjam; Unal, Ekrem

    2015-09-01

    The hyper-immunoglobulin M (HIGM) syndrome is a heterogeneous group of genetic disorders characterized by recurrent infections, decreased serum levels of immunoglobulin G (IgG) and IgA, and normal/increased serum levels of IgM. Herein, we describe three Turkish siblings with HIGM syndrome who had a homozygous missense mutation (c.70C>T, p.Arg24Trp) in the activation-induced cytidine deaminase gene which results in autosomal recessive HIGM syndrome. Two of the siblings, sibling 1 and sibling 3, presented with cervical deep abscess and cervical tuberculosis lymphadenitis, respectively.

  7. Prevalence of Latent and Active Tuberculosis among Dairy Farm Workers Exposed to Cattle Infected by Mycobacterium bovis

    PubMed Central

    Torres-Gonzalez, Pedro; Soberanis-Ramos, Orbelin; Martinez-Gamboa, Areli; Chavez-Mazari, Barbara; Barrios-Herrera, Ma Teresa; Torres-Rojas, Martha; Cruz-Hervert, Luis Pablo; Garcia-Garcia, Lourdes; Singh, Mahavir; Gonzalez-Aguirre, Adrian; Ponce de Leon-Garduño, Alfredo; Sifuentes-Osornio, José; Bobadilla-del-Valle, Miriam

    2013-01-01

    Background Human tuberculosis caused by M. bovis is a zoonosis presently considered sporadic in developed countries, but remains a poorly studied problem in low and middle resource countries. The disease in humans is mainly attributed to unpasteurized dairy products consumption. However, transmission due to exposure of humans to infected animals has been also recognized. The prevalence of tuberculosis infection and associated risk factors have been insufficiently characterized among dairy farm workers (DFW) exposed in settings with poor control of bovine tuberculosis. Methodology/Principal Findings Tuberculin skin test (TST) and Interferon-gamma release assay (IGRA) were administered to 311 dairy farm and abattoir workers and their household contacts linked to a dairy production and livestock facility in Mexico. Sputa of individuals with respiratory symptoms and samples from routine cattle necropsies were cultured for M. bovis and resulting spoligotypes were compared. The overall prevalence of latent tuberculosis infection (LTBI) was 76.2% (95% CI, 71.4–80.9%) by TST and 58.5% (95% CI, 53.0–64.0%) by IGRA. Occupational exposure was associated to TST (OR 2.72; 95% CI, 1.31–5.64) and IGRA (OR 2.38; 95% CI, 1.31–4.30) adjusting for relevant variables. Two subjects were diagnosed with pulmonary tuberculosis, both caused by M. bovis. In one case, the spoligotype was identical to a strain isolated from bovines. Conclusions We documented a high prevalence of latent and pulmonary TB among workers exposed to cattle infected with M. bovis, and increased risk among those occupationally exposed in non-ventilated spaces. Interspecies transmission is frequent and represents an occupational hazard in this setting. PMID:23638198

  8. Deregulated lncRNAs in B Cells from Patients with Active Tuberculosis

    PubMed Central

    Fu, Yurong; Xu, Xianqin; Xue, Junfang; Duan, Wenping; Yi, Zhengjun

    2017-01-01

    Role of lncRNAs in human adaptive immune response to TB infection is largely unexplored. To address this issue, here we characterized lncRNA expression profile in primary human B cell response to TB infection using microarray assay. Several lncRNAs and mRNAs were chosen for RT-qPCR validation. Bioinformatics prediction was applied to delineate function of the deregulated mRNAs. We found that 844 lncRNAs and 597 mRNAs were differentially expressed between B cell samples from individuals with or without TB. KEGG pathway analysis for the deregulated mRNAs indicated a number of pathways, such as TB, TLR signaling pathway and antigen processing and presentation. Moreover, corresponding to the dysregulation of many lncRNAs, we also found that their adjacent protein-coding genes were also deregulated. Functional annotation for the corresponding mRNAs showed that these lncRNAs were mainly associated with TLR signaling, TGF-β signaling. Interestingly, SOCS3, which is a critical negative regulator of cytokine response to TB infection and its nearby lncRNA XLOC_012582, were highly expressed in active TB B cells. Subsequent RT-qPCR results confirmed the changes. Whether upregulated XLOC_012582 causes SOCS3 overexpression and is eventually involved in the context of exacerbations of active TB represents an interesting issue that deserves to be further explored. Taken together, for the first time, we identified a set of deregulated lncRNAs in active TB B cells and their functions were predicted. Such findings provided novel insight into the pathogenesis of TB and further studies should focus on the function and pathogenic mechanisms of the lncRNAs involved in active TB. PMID:28125665

  9. Evaluation of a whole-blood chemiluminescent immunoassay of IFN-γ, IP-10, and MCP-1 for diagnosis of active pulmonary tuberculosis and tuberculous pleurisy patients.

    PubMed

    Liang, Yan; Wang, Ying; Li, Hang; Yang, Yourong; Liu, Jianyang; Yu, Ting; Wu, Xueqiong

    2016-10-01

    The study explored the use of IP-10, MCP-1, and IFN-γ as biomarkers to improve the diagnoses of active pulmonary tuberculosis and tuberculous pleurisy. We enrolled 267 individuals, including 134 TB patients, 93 patients with non-tuberculous pulmonary diseases, and 40 healthy controls. Whole bloods were stimulated in vitro with rCFP-10/ESAT-6 protein antigen of Mycobacterium tuberculosis. The levels of IFN-γ, IP-10, and MCP-1 in cultured supernatants of whole bloods were detected by a chemiluminescence immunoassay. A receiver operating characteristic (ROC) curve was drawn to determine the cutoff value for diagnosing TB and to evaluate the diagnostic efficacies of the IFN-γ, IP-10, and MCP-1 for TB. The antigen-specific release of each cytokine, IFN-γ, IP-10, and MCP-1, was significantly higher in the TB groups than in either the non-tuberculous pulmonary disease group (p < 0.001) or the healthy control group (p < 0.001). The ROC curves indicated cutoff values for IFN-γ, IP-10, and MCP-1 at 147.8, 160.4, and 496.4 pg/mL, respectively. The sensitivity, specificity, PPV, NPV, and diagnostic efficiency for IFN-γ were 85.8%, 70.7%, 74.7%, 83.2%, and 78.3%, respectively; for IP-10 were 72.4%, 75.9%, 75.2%, 73.2%, and 74.2%, respectively; and for MCP-1 were 90.3%, 97.0%, 96.8%, 90.8%, and 93.6%, respectively. IFN-γ combined MCP-1 improved the sensitivity to 97.8% compared with IFN-γ (p < 0.001). Our findings indicate high sensitivity and specificity of MCP-1 as novel biomarkers for the diagnosis of active pulmonary tuberculosis and tuberculous pleurisy.

  10. Nested reverse transcriptase-polymerase chain reactions targeting the messenger RNA of icl2, hspx, and rRNAP1 genes to detect viable Mycobacterium tuberculosis directly from clinical specimens.

    PubMed

    Lakshmipathy, Dhanurekha; Kulandai, Lily Therese; Ramasubban, Gayathri; Hajib Narahari Rao, Madhavan; Rathinam, Sridhar; Narasimhan, Meenakshi

    2015-12-01

    There is an urgent need for a rapid and reliable test to detect actively multiplying Mycobacterium tuberculosis directly from clinical specimens for an early initiation of the appropriate antituberculous treatment. This study was aimed at the optimization and application of nested reverse transcriptase-PCR (nRT-PCR) targeting the messenger RNA of the icl2, hspx, and rRNAP1 genes directly from sputum specimens, and their evaluation against the culture by the BACTEC MicroMGIT mycobacterial culture system. 203 Sputum samples from clinically suspected tuberculosis patients and 30 control specimens (clinically proven viral or bacterial infections other than tuberculosis) were included in this study. The mycobacterial culture was performed by the BACTEC MicroMGIT system following the manufacturer's instructions. The primers for nRT-PCRs targeting icl2, hspx, and rRNAP1 genes were indigenously designed using the Primer-BLAST software, and optimized for sensitivity and specificity. The icl2, hspx, and rRNAP1 genes were able to pick up 63.9%, 67.2%, and 58.75%, respectively, of culture-negative sputum specimens collected from clinically suspected tuberculosis patients. However, three (1.4%) were negative for nRT-PCR, but M. tuberculosis culture positive. All the 30 controls were negative for culture by the BACTEC MicroMGIT method and all three nRT-PCR. The novel nRT-PCRs targeting icl2, hspx, and rRNAP1 genes developed in this study are rapid and reliable diagnostic tools to detect viable M. tuberculosis directly from sputum specimens. However, further study by including a larger number of sputum specimens needs to be carried out to ascertain the diagnostic utility of the novel nRT-PCRs optimized in the study.

  11. Primary gastric tuberculosis – report of 5 cases

    PubMed Central

    Amarapurkar, Deepak N; Patel, Nikhil D; Amarapurkar, Anjali D

    2003-01-01

    Background Gastric tuberculosis is rare, and usually associated with pulmonary tuberculosis or an immunodeficient state. Here, we report five cases of gastric tuberculosis in immunocompetent patients without evidence of pulmonary involvement. Case presentation Three patients presented with gastric outlet obstruction that required surgery to relieve the obstruction as well as to confirm the diagnosis. The remaining two had involvement of gastroesophageal junction. All of them responded well to standard antitubercular treatment. Conclusion Though gastric tuberculosis is rare, it should be considered a possibility when patients present with gastric outlet obstruction or with endoscopic evidence of diffuse chronic inflammatory activity, particularly in areas endemic for tuberculosis. PMID:12703983

  12. Computerized feature systems for identifying suspects

    NASA Astrophysics Data System (ADS)

    Lee, Eric; Whalen, Thom; McCarthy, Andrew; Sakalauskas, John; Wotton, Cynthia

    1995-09-01

    In suspect identification, witnesses examine photos of known offenders in mugshot albums. The probability of correct identification deteriorates rapidly, however, as the number of mugshots examined increases. Feature approaches, where mugshots are displayed in order of similarity to witness descriptions of suspects, increase identification success by reducing this number. In our computerized feature system, both police raters and witnesses describe facial features of suspects on rating scales such as nose size: small 1 2 3 4 5 large. Feature users consistently identify more target suspects correctly than do album users. Previous experimental tests have failed, however, to examine the effects of feature system performance of the use of live targets as suspects rather than photos, the use of realistic crime scenarios, the number of police raters/mugshot, and differences among raters in their effect on system perfomance. In three experiments, we investigated those four issues. The first experiment used photos as target suspects but with multiple distractors, the second tested live suspects, while the third tested live suspects in a realistic crime scenario. The database contained the official mugshots of 1,000 offenders. Across the three experiments, a second and sometimes a third rater/mugshot significantly reduced the number of photos examined. More raters/mugshot did not affect performance further. Raters differed significantly in their effect on system perfomance. Significantly, our feature system performed well both with target suspects seen live and with live suspects in realistic crime scenarios (performance was comparable to that in previous experiments for photos of target suspects). These results strongly support our contention that feature systems are superior to album systems.

  13. CT-Guided Transthoracic Core Biopsy for Pulmonary Tuberculosis: Diagnostic Value of the Histopathological Findings in the Specimen

    SciTech Connect

    Fukuda, Hozumi Ibukuro, Kenji; Tsukiyama, Toshitaka; Ishii, Rei

    2004-09-15

    We evaluated the value of CT-guided transthoracic core biopsy for the diagnosis of mycobacterial pulmonary nodules. The 30 subjects in this study had pulmonary nodules that had been either diagnosed histopathologically as tuberculosis or were suspected as tuberculosis based on a specimen obtained by CT-guided transthoracic core biopsy. The histopathological findings, the existence of acid-fast bacilli in the biopsy specimens, and the clinical course of the patients after the biopsy were reviewed retrospectively. Two of the three histological findings for tuberculosis that included epithelioid cells, multinucleated giant cells and caseous necrosis were observed in 21 of the nodules which were therefore diagnosed as histological tuberculosis. Six of these 21 nodules were positive for acid-fast bacilli, confirming the diagnosis of tuberculosis. Thirteen of the 21 nodules did not contain acid-fast bacilli but decreased in size in response to antituberculous treatment and were therefore diagnosed as clinical tuberculosis. Seven nodules with only caseous necrosis were diagnosed as suspected tuberculosis, with a final diagnosis of tuberculosis being made in 4 of the nodules and a diagnosis of old tuberculosis in 2 nodules. Two nodules with only multinucleated giant cells were diagnosed as suspected tuberculosis with 1 of these nodules being diagnosed finally as tuberculosis and the other nodule as a nonspecific granuloma. When any two of the three following histopathological findings - epithelioid cells, multinucleated giant cells or caseous necrosis - are observed in a specimen obtained by CT-guided transthoracic core biopsy, the diagnosis of tuberculosis can be established without the detection of acid-fast bacilli or Mycobacterium tuberculosis.

  14. Positive anti‐cyclic citrullinated proteins and rheumatoid factor during active lung tuberculosis

    PubMed Central

    Elkayam, O; Segal, R; Lidgi, M; Caspi, D

    2006-01-01

    Objectives To determine the prevalence of anti‐cyclic citrullinated proteins (anti‐CCP) and IgM rheumatoid factor (RF) in sera of patients with TB compared with healthy controls. Patients and methods 47 consecutive patients with recently diagnosed active pulmonary TB and 39 healthy controls were studied. Data were collected by questionnaire on clinical features of the disease, duration of symptoms, fever, cough, arthralgia, myalgia, sicca symptoms. Serum samples were collected from patients before starting treatment for TB and frozen at −20°C. Anti‐CCP and IgM RF were evaluated by ELISA. Results The mean (SD) duration of TB related symptoms was 4.4 (1.7) months, 73% had fever, 94% a cough. Rheumatic symptoms were relatively rare: arthralgia (4%), myalgias (4%), eye and mouth dryness (2% and 9%, respectively). Mean (SD) levels of anti‐CCP were significantly increased in patients with TB compared with controls: 44.9 (51) IU v 20 (7.3) IU (p = 0.002). Serum levels >40 U were found in 15/47 (32%) patients compared with 1/39 (2.6%) controls (p = 0.002). Mean (SD) serum levels of IgM RF were significantly increased in patients with TB: 17.8 (19) v 4.3 (5) (p<0.0001). IgM RF was positive (>6 IU) in 29/47 (62%) patients v 1/39 (2.6%) controls (p<0.0001). Conclusions A significant proportion of patients with active TB have an increased titre of anti‐CCP and IgM RF. PMID:16361276

  15. Mathematical Models of Tuberculosis Reactivation and Relapse

    PubMed Central

    Wallis, Robert S.

    2016-01-01

    The natural history of human infection with Mycobacterium tuberculosis (Mtb) is highly variable, as is the response to treatment of active tuberculosis. There is presently no direct means to identify individuals in whom Mtb infection has been eradicated, whether by a bactericidal immune response or sterilizing antimicrobial chemotherapy. Mathematical models can assist in such circumstances by measuring or predicting events that cannot be directly observed. The 3 models discussed in this review illustrate instances in which mathematical models were used to identify individuals with innate resistance to Mtb infection, determine the etiologic mechanism of tuberculosis in patients treated with tumor necrosis factor blockers, and predict the risk of relapse in persons undergoing tuberculosis treatment. These examples illustrate the power of various types of mathematic models to increase knowledge and thereby inform interventions in the present global tuberculosis epidemic. PMID:27242697

  16. Suspected infection in afebrile patients

    PubMed Central

    Martins, Fernanda de Souza; Guedes, Gisele Giuliane; Santos, Thiago Martins; de Carvalho-Filho, Marco A.

    2017-01-01

    Abstract We prospectively evaluated afebrile patients admitted to an emergency department (ED), with suspected infection and only tachycardia or tachypnea. The white blood cell count (WBC) was obtained, and patients were considered septic if leukocyte count was >12,000 μL–1 or <4000 μL–1 or with >10% of band forms. Clinical data were collected to examine whether sepsis could be predicted. Seventy patients were included and 37 (52.86%) met sepsis criteria. Self-measured fever showed an odds ratio (OR) of 5.936 (CI95% 1.450–24.295; P = 0.0133) and increased pulse pressure (PP) showed an OR of 1.405 (CI95% 1.004–1.964; P = 0.0471) on multivariate analysis. When vital signs were included in multivariate analysis, the heart rate showed an OR of 2.112 (CI95% 1.400–3.188; P = 0.0004). Self-measured fever and mean arterial pressure <70 mm Hg had high positive likelihood ratios (3.86 and 2.08, respectively). The nomogram for self-measured fever showed an increase of sepsis chance from 53% (pretest) to approximately 80% (post-test). The recognition of self-measured fever, increased PP, and the intensity of heart rate response may improve sepsis recognition in afebrile patients with tachycardia or tachypnea. These results are important for medical assessment of sepsis in remote areas, crowded and low-resourced EDs, and low-income countries, where WBC may not be readily available. PMID:28272257

  17. [Tuberculosis of the pancreas--a clinical rarity].

    PubMed

    Heitmann, P; Kratsch, B; Löschke, S; Klempa, I

    2001-06-01

    Pancreas tuberculosis is a rare diagnosis and is usually associated with miliary spread. Only a few cases are reported in the literature. A female patient was admitted with a history of uncharacteristic abdominal pain, weight loss, weakness, and intermittent fever. CA 19-9 was increased and the CT scan showed an irregular mass in the pancreatic tail. Suspecting the diagnosis of pancreatic cancer, a pancreas tail resection with splenectomy was performed. The histological examination showed pancreas tuberculosis. Mimicking pancreatic cancer or presenting with acute/chronic pancreatitis or obstructive jaundice, the diagnosis of pancreas tuberculosis is very difficult to make and is usually established after surgical treatment. Although pancreas tuberculosis is rare, it should be considered when evaluating a pancreatic mass.

  18. Mycobacterium tuberculosis PE25/PPE41 protein complex induces activation and maturation of dendritic cells and drives Th2-biased immune responses.

    PubMed

    Chen, Wei; Bao, Yige; Chen, Xuerong; Burton, Jeremy; Gong, Xueli; Gu, Dongqing; Mi, Youjun; Bao, Lang

    2016-04-01

    Mycobacterium tuberculosis evades innate host immune responses by parasitizing macrophages and causes significant morbidity and mortality around the world. A mycobacterial antigen that can activate dendritic cells (DCs) and elicit effective host innate immune responses will be vital to the development of an effective TB vaccine. The M. tuberculosis genes PE25/PPE41 encode proteins which have been associated with evasion of the host immune response. We constructed a PE25/PPE41 complex gene via splicing by overlapping extension and expressed it successfully in E. coli. We investigated whether this protein complex could interact with DCs to induce effective host immune responses. The PE25/PPE41 protein complex induced maturation of isolated mouse DCs in vitro, increasing expression of cell surface markers (CD80, CD86 and MHC-II), thereby promoting Th2 polarization via secretion of pro-inflammatory cytokines IL-4 and IL-10. In addition, PE25/PPE41 protein complex-activated DCs induced proliferation of mouse CD4(+) and CD8(+) T cells, and a strong humoral response in immunized mice. The sera of five TB patients were also highly reactive to this antigen. These findings suggest that interaction of the PE25/PPE41 protein complex with DCs may be of great immunological significance.

  19. The antimicrobial activity of copper and copper alloys against nosocomial pathogens and Mycobacterium tuberculosis isolated from healthcare facilities in the Western Cape: an in-vitro study.

    PubMed

    Mehtar, S; Wiid, I; Todorov, S D

    2008-01-01

    Clinical isolates of meticillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Candida albicans and Mycobacterium tuberculosis (MTB) were tested against copper (Cu) and its alloys. Stainless steel and polyvinylchloride (PVC) were used as controls. The amount of Cu required to inhibit test isolates at room temperature (24 degrees C) and at 4 degrees C was determined. At room temperature, Cu, DZR Brass (Cu 62%, Pb 2.5%, arsenate 0.13% and Zn 22.5%) and Brass 70/30 (Cu 70% and zinc 30%) inhibited C. albicans and K. pneumoniae at 60 min; nickel silver (NiAg) inhibited C. albicans at 60 min and K. pneumoniae at 270 min. P. aeruginosa was inhibited by Brass 70/30 and nickel silver (NiAg) at 180 min and at 270 min by Cu and DZR. Cu and DZR inhibited A. baumannii at 180 min while the other alloys were effective at 360 min. Stainless steel and PVC showed little or no inhibitory activity. Two M. tuberculosis strains, one isoniazid resistant (R267) and the other multidrug resistant (R432), demonstrated growth inhibition with Cu of 98% and 88% respectively compared with PVC; the other alloys were less active. Time to positivity (TTP) for R267 was >15 days with Cu and 11 days for the other alloys; with R432 it was 5 days. Effective inhibition of nosocomial pathogens and MTB by Cu and alloys was best when the Cu content was >55%.

  20. In silico discovery and in vitro activity of inhibitors against Mycobacterium tuberculosis 7,8-diaminopelargonic acid synthase (Mtb BioA)

    PubMed Central

    Billones, Junie B; Carrillo, Maria Constancia O; Organo, Voltaire G; Sy, Jamie Bernadette A; Clavio, Nina Abigail B; Macalino, Stephani Joy Y; Emnacen, Inno A; Lee, Alexandra P; Ko, Paul Kenny L; Concepcion, Gisela P

    2017-01-01

    Computer-aided drug discovery and development approaches such as virtual screening, molecular docking, and in silico drug property calculations have been utilized in this effort to discover new lead compounds against tuberculosis. The enzyme 7,8-diaminopelargonic acid aminotransferase (BioA) in Mycobacterium tuberculosis (Mtb), primarily involved in the lipid biosynthesis pathway, was chosen as the drug target due to the fact that humans are not capable of synthesizing biotin endogenously. The computational screening of 4.5 million compounds from the Enamine REAL database has ultimately yielded 45 high-scoring, high-affinity compounds with desirable in silico absorption, distribution, metabolism, excretion, and toxicity properties. Seventeen of the 45 compounds were subjected to bioactivity validation using the resazurin microtiter assay. Among the 4 actives, compound 7 ((Z)-N-(2-isopropoxyphenyl)-2-oxo-2-((3-(trifluoromethyl)cyclohexyl)amino)acetimidic acid) displayed inhibitory activity up to 83% at 10 μg/mL concentration against the growth of the Mtb H37Ra strain. PMID:28280303

  1. Active Case Finding of Pulmonary Tuberculosis through Screening of Respiratory Symptomatics Using Sputum Microscopy: Is It Time to Change the Paradigm?

    PubMed Central

    del Portillo-Mustieles, Eva Carolina; Laniado-Laborín, Rafael

    2013-01-01

    Background. One of the main strategies for the early detection of pulmonary tuberculosis (PTB) is through the screening of individuals with symptoms compatible with PTB. Although this is programmatic strategy for active case finding, its yield is not well known. Objective. To determine the yield of pulmonary tuberculosis active case finding through the screening of respiratory symptomatic (RS) patients at a general hospital. Methods. RS patients were defined as subjects complaining of cough and/or sputum for a period of 2 or more weeks. Outpatients and their companions were approached while they waited in the outpatient care areas of the hospital to detect RS. Two samples from different days or 2 samples taken 2 hours apart on the same day were collected. Results. 122 RS patients were identified. Fifty-seven patients (46.7%) had at least one sputum sample analyzed. Three patients presented a positive smear and 2 were culture positive; neither had upper airway symptoms. None of the patients with productive cough and upper airway symptoms had a positive smear (P = 0.07). Only 19 (33.3%) returned to the laboratory to retrieve their results. Conclusion. Current strategy to screen RS patients based only on clinical data has a low compliance. Specific strategies to increase compliance (removal of barriers, incentives, etc.) should be implemented. PMID:23533747

  2. Mycobacterium tuberculosis PstS1 amplifies IFN-γ and induces IL-17/IL-22 responses by unrelated memory CD4+ T cells via dendritic cell activation.

    PubMed

    Palma, Carla; Schiavoni, Giovanna; Abalsamo, Laura; Mattei, Fabrizio; Piccaro, Giovanni; Sanchez, Massimo; Fernandez, Carmen; Singh, Mahavir; Gabriele, Lucia

    2013-09-01

    The immunological mechanisms that modulate protection during Mycobacterium tuberculosis (Mtb) infection or vaccination are not fully understood. Secretion of IFN-γ and, to a lesser extent, of IL-17 by CD4(+) T cells plays a major role both in protection and immunopathology. Few Mtb Ags interacting with DCs affect priming, activation, and regulation of Ag-unrelated CD4(+) T-cell responses. Here we demonstrate that PstS1, a 38 kDa-lipoprotein of Mtb, promotes Ag-independent activation of memory T lymphocytes specific for Ag85B or Ag85A, two immunodominant protective Ags of Mtb. PstS1 expands CD4(+) and CD8(+) memory T cells, amplifies secretion of IFN-γ and IL-22 and induces IL-17 production by effector memory cells in an Ag-unrelated manner in vitro and in vivo. These effects were mediated through the stimulation of DCs, particularly of the CD8α(-) subtype, which respond to PstS1 by undergoing phenotypic maturation and by secreting IL-6, IL-1β and, to a lower extent, IL-23. IL-6 secretion by PstS1-stimulated DCs was required for IFN-γ, and to a lesser extent for IL-22 responses by Ag85B-specific memory T cells. These results may open new perspectives for immunotherapeutic strategies to control Th1/Th17 immune responses in Mtb infections and in vaccinations against tuberculosis.

  3. Structure-based design of diverse inhibitors of Mycobacterium tuberculosis N-acetylglucosamine-1-phosphate uridyltransferase: combined molecular docking, dynamic simulation, and biological activity.

    PubMed

    Soni, Vijay; Suryadevara, Priyanka; Sriram, Dharmarajan; Kumar, Santhosh; Nandicoori, Vinay Kumar; Yogeeswari, Perumal

    2015-07-01

    Persistent nature of Mycobacterium tuberculosis is one of the major factors which make the drug development process monotonous against this organism. The highly lipophilic cell wall, which constituting outer mycolic acid and inner peptidoglycan layers, acts as a barrier for the drugs to enter the bacteria. The rigidity of the cell wall is imparted by the peptidoglycan layer, which is covalently linked to mycolic acid by arabinogalactan. Uridine diphosphate-N-acetylglucosamine (UDP-GlcNAc) serves as the starting material in the biosynthesis of this peptidoglycan layers. This UDP-GlcNAc is synthesized by N-acetylglucosamine-1-phosphate uridyltransferase (GlmU(Mtb)), a bi-functional enzyme with two functional sites, acetyltransferase site and uridyltransferase site. Here, we report design and screening of nine inhibitors against UTP and NAcGlc-1-P of uridyltransferase active site of glmU(Mtb). Compound 4 was showing good inhibition and was selected for further analysis. The isothermal titration calorimetry (ITC) experiments showed the binding energy pattern of compound 4 to the uridyltransferase active site is similar to that of substrate UTP. In silico molecular dynamics (MD) simulation studies, for compound 4, carried out for 10 ns showed the protein-compound complex to be stable throughout the simulation with relative rmsd in acceptable range. Hence, these compounds can serve as a starting point in the drug discovery processes against Mycobacterium tuberculosis.

  4. The Phenomenology of Specialization of Criminal Suspects

    PubMed Central

    Tumminello, Michele; Edling, Christofer; Liljeros, Fredrik; Mantegna, Rosario N.; Sarnecki, Jerzy

    2013-01-01

    A criminal career can be either general, with the criminal committing different types of crimes, or specialized, with the criminal committing a specific type of crime. A central problem in the study of crime specialization is to determine, from the perspective of the criminal, which crimes should be considered similar and which crimes should be considered distinct. We study a large set of Swedish suspects to empirically investigate generalist and specialist behavior in crime. We show that there is a large group of suspects who can be described as generalists. At the same time, we observe a non-trivial pattern of specialization across age and gender of suspects. Women are less prone to commit crimes of certain types, and, for instance, are more prone to specialize in crimes related to fraud. We also find evidence of temporal specialization of suspects. Older persons are more specialized than younger ones, and some crime types are preferentially committed by suspects of different ages. PMID:23691257

  5. Guidelines for identifying suspect/counterfeit material

    SciTech Connect

    1995-09-01

    These guidelines are intended to assist users of products in identifying: substandard, misrepresented, or fraudulently marked items. The guidelines provide information about such topics as: precautions, inspection and testing, dispositioning identified items, installed inspection and reporting suspect/counterfeit materials. These guidelines apply to users who are developing procurement documents, product acceptance/verification methods, company procedures, work instructions, etc. The intent of these SM guidelines in relation to the Quality Assurance Program Description (QAPD) and implementing company Management Control Procedures is not to substitute or replace existing requirements, as defined in either the QAPD or company implementing instructions (Management Control Procedures). Instead, the guidelines are intended to provide a consolidated source of information addressing the issue of Suspect/Counterfeit materials. These guidelines provide an extensive suspect component listing and suspect indications listing. Users can quickly check their suspect items against the list of manufacturers products (i.e., type, LD. number, and nameplate information) by consulting either of these listings.

  6. [Ag85B and BCG enhance immune activity of dendritic cells in patients with initially treated tuberculosis].

    PubMed

    Guo, Yun; Su, Yuanyuan; Sun, Yang; Guan, Weiwei; Yang, Li; Zhang, Zhi; Wang, Yuling; Dai, Erhei

    2016-06-01

    Objective To investigate the regulatory effects of Mycobacterium tuberculosis major secreted protein Ag85B and Bacillus Calmette-Guerin (BCG) on the immune function of dendritic cells (DCs) in the patients with tuberculosis who have received an initial treatment. Methods The peripheral blood mononuclear cells were collected and separated in 26 healthy subjects and 31 patients with tuberculosis who had been treated initially. Every specimen was divided into 4 groups and DCs were induced and cultured. On the 6th day, the DCs in the three experimental groups were treated by lipopolysaccharide (LPS), BCG, Ag85B, respectively and no-treated DCs served as a control group. After 24-hour treatment, DCs were collected and examined for the levels of CD83, CD86, HLA-DR and CD11c using flow cytometry. Moreover, the levels of interleukin 12 (IL-12), IL-10 and interferon γ (IFN-γ) in the supernatants were measured by ELISA. Results The expression levels of CD83 and IL-10 in the patient control group were significantly lower than those in healthy subject control group. The levels of CD83, CD86 and IFN-γ in the Ag85B treated group were obviously high than those in the control group. The level of IFN-γ in the BCG treated group was significantly high than that in the control group. The levels of CD83, CD86, HLA-DR and IL-10 in the LPS treated group were remarkably higher than those in the control group. The levels of CD83, CD86 and IL-10 in the healthy subject LPS treated group were significantly higher than those in the healthy subject control group. Conclusion The immune-enhancing effect of Ag85B on DCs is superior to that of BCG in the patients with initially treated tuberculosis.

  7. Mitigating Financial Burden of Tuberculosis through Active Case Finding Targeting Household and Neighbourhood Contacts in Cambodia

    PubMed Central

    Morishita, Fukushi; Yadav, Rajendra-Prasad; Eang, Mao Tan; Saint, Saly; Nishikiori, Nobuyuki

    2016-01-01

    Background Despite free TB services available in public health facilities, TB patients often face severe financial burden due to TB. WHO set a new global target that no TB-affected families experience catastrophic costs due to TB. To monitor the progress and strategize the optimal approach to achieve the target, there is a great need to assess baseline cost data, explore potential proxy indicators for catastrophic costs, and understand what intervention mitigates financial burden. In Cambodia, nationwide active case finding (ACF) targeting household and neighbourhood contacts was implemented alongside routine passive case finding (PCF). We analyzed household cost data from ACF and PCF to determine the financial benefit of ACF, update the baseline cost data, and explore whether any dissaving patterns can be a proxy for catastrophic costs in Cambodia. Methods In this cross-sectional comparative study, structured interviews were carried out with 108 ACF patients and 100 PCF patients. Direct and indirect costs, costs before and during treatment, costs as percentage of annual household income and dissaving patterns were compared between the two groups. Results The median total costs were lower by 17% in ACF than in PCF ($240.7 [IQR 65.5–594.6] vs $290.5 [IQR 113.6–813.4], p = 0.104). The median costs before treatment were significantly lower in ACF than in PCF ($5.1 [IQR 1.5–25.8] vs $22.4 [IQR 4.4–70.8], p<0.001). Indirect costs constituted the largest portion of total costs (72.3% in ACF and 61.5% in PCF). Total costs were equivalent to 11.3% and 18.6% of annual household income in ACF and PCF, respectively. ACF patients were less likely to dissave to afford TB-related expenses. Costs as percentage of annual household income were significantly associated with an occurrence of selling property (p = 0.02 for ACF, p = 0.005 for PCF). Conclusions TB-affected households face severe financial hardship in Cambodia. ACF has the great potential to mitigate the costs

  8. Unusual presentation of renal tuberculosis.

    PubMed

    Chaudhari, Aunp P; Ranganath, Ravi; Pavan, Malleshappa

    2011-07-01

    Urogenital tuberculosis (TB) is a common late manifestation of an earlier symptomatic or asymptomatic pulmonary TB infection. A latency period ranging from 5 to 40 years between the time of the initial infection and the expression of urogenital TB frequently occurs. As one of the most common sites of involvement of extrapulmonary TB, urogenital TB accounts for 15% to 20% of the infections. We present a patient who had culture-negative active tubercular kidney disease due to silent tuberculous infection. Our case demonstrates the limitations of noninvasive testing in establishing the diagnosis of renal tuberculosis.

  9. Optimal intervention strategies for tuberculosis

    NASA Astrophysics Data System (ADS)

    Bowong, Samuel; Aziz Alaoui, A. M.

    2013-06-01

    This paper deals with the problem of optimal control of a deterministic model of tuberculosis (abbreviated as TB for tubercle bacillus). We first present and analyze an uncontrolled tuberculosis model which incorporates the essential biological and epidemiological features of the disease. The model is shown to exhibit the phenomenon of backward bifurcation, where a stable disease-free equilibrium co-exists with one or more stable endemic equilibria when the associated basic reproduction number is less than the unity. Based on this continuous model, the tuberculosis control is formulated and solved as an optimal control problem, indicating how control terms on the chemoprophylaxis and detection should be introduced in the population to reduce the number of individuals with active TB. Results provide a framework for designing the cost-effective strategies for TB with two intervention methods.

  10. What's new in tuberculosis vaccines?

    PubMed Central

    Ginsberg, Ann M.

    2002-01-01

    Over the past 10 years, tuberculosis (TB) vaccine development has resurged as an active area of investigation. The renewed interest has been stimulated by the recognition that, although BCG is delivered to approximately 90% of all neonates globally through the Expanded Programme on Immunization, Mycobacterium tuberculosis continues to cause over 8 million new cases of TB and over 2 million deaths annually. Over one hundred TB vaccine candidates have been developed, using different approaches to inducing protective immunity. Candidate vaccines are typically screened in small animal models of primary TB disease for their ability to protect against a virulent strain of M. tuberculosis. The most promising are now beginning to enter human safety trials, marking real progress in this field for the first time in 80 years. PMID:12132007

  11. Human Tuberculosis II. M. tuberculosis Mechanisms of Genetic and Phenotypic Resistance to Anti-Tuberculosis Drugs.

    PubMed

    Sgaragli, Giampietro; Frosini, Maria

    2016-01-01

    The great progress of knowledge of both M. tuberculosis physiology and how human host and bacilli interact has provided fertile ground for improving diagnosis and cure of TB infection. Once M. tuberculosis has infected humans, it elaborates strategies for evading the risk to killing by the cells of the host immune system and by the anti-tuberculosis (anti-TB) agents employed to cure infection. These strategies give rise to a bacterial multidrug resistance (MDR) status. This stems firstly from genetic mutations targeting a constellation of drug-processing mechanisms that still need full identification, as drug efflux pumps and drug activating/ inactivating enzymes (genetic resistance). Secondly, from the bacterial adaptation to stressful environmental conditions by adopting a temporary dormancy state lasting for decades and characterized by indifference to anti-TB drugs (phenotypic resistance or tolerance). The clarification of the strategies elaborated for surviving by M. tuberculosis has brought to the identification in the last few years of a number of mycobacterial molecular targets worth to exploitation for the development of novel and powerful anti-TB drugs. These targets include drug-efflux pump systems, considered partly responsible for genetic multi-drug resistance, and several enzymes and pump systems, as well, that sustain the metabolic adaptations of M. tuberculosis in the host and give rise to its phenotypic drug resistance.

  12. Combined Analysis of IFN-γ, IL-2, IL-5, IL-10, IL-1RA and MCP-1 in QFT Supernatant Is Useful for Distinguishing Active Tuberculosis from Latent Infection.

    PubMed

    Suzukawa, Maho; Akashi, Shunsuke; Nagai, Hideaki; Nagase, Hiroyuki; Nakamura, Hiroyuki; Matsui, Hirotoshi; Hebisawa, Akira; Ohta, Ken

    2016-01-01

    The QuantiFERON®-TB Gold In-Tube test (QFT), an interferon-γ release assay, is used to diagnose Mycobacterium tuberculosis, but its inaccuracy in distinguishing active tuberculosis from latent infection is a major concern. There is thus a need for an easy and accurate tool for achieving that goal in daily clinical settings. This study aimed to identify candidate cytokines for specifically differentiating active tuberculosis from latent infection. Our study population consisted of 31 active TB (tuberculosis) patients, 29 LTBI (latent tuberculosis infection) patients and 10 healthy control subjects. We assayed for 27 cytokines in QFT supernatants of both specific antigen-stimulated blood samples (TBAg) and negative-control samples (Nil). We analyzed their specificities and sensitivities by creating receiver operating characteristic (ROC) curves and measuring the area under those curves (AUCs). In TBAg-Nil supernatants, IL-10, IFN-γ, MCP-1 and IL-1RA showed high AUCs of 0.8120, 0.7842, 0.7419 and 0.7375, respectively. Compared with each cytokine alone, combined assay for these top four cytokines showed positive rates in diagnosing active TB, and GDA analysis revealed that MCP-1 and IL-5 are potent in distinguishing active TB from LTBI, with Wilk's lambda = 0.718 (p < 0.001). Furthermore, utilizing the unique characteristic of IL-2 that its TBAg-Nil supernatant levels are higher in LTBI compared to active TB, the difference between IFN-γ and IL-2 showed a large AUC of 0.8910. In summary, besides IFN-γ, IL-2, IL-5, IL-10, IL-1RA and MCP-1 in QFT supernatants may be useful for distinguishing active TB from LTBI. Those cytokines may also help us understand the difference in pathogenesis between active TB and LTBI.

  13. New prodrugs against tuberculosis.

    PubMed

    Mori, Giorgia; Chiarelli, Laurent Roberto; Riccardi, Giovanna; Pasca, Maria Rosalia

    2017-03-01

    The term 'prodrug' was first introduced by Albert in 1958. Generally, prodrugs can be utilized for improving active drug solubility and bioavailability, increasing drug permeability and absorption, modifying the distribution profile, preventing fast metabolism and excretion, and reducing toxicity. Previously, the prodrug approach was a final resort during the drug discovery process only after all other approaches had been exhausted. However, this strategy is now considered during the early stages of the drug development process. Most antitubercular agents are defined as 'prodrugs', including isoniazid and ethionamide. Thus, the prodrug approach could provide novel targets for the rational design of more effective treatments for tuberculosis (TB).

  14. Tuberculosis Data and Statistics

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Tuberculosis (TB) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Tuberculosis Basic TB Facts How TB Spreads Latent TB ...

  15. Tuberculosis Treatment and Pregnancy

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Tuberculosis (TB) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Tuberculosis Basic TB Facts How TB Spreads Latent TB ...

  16. [Detection of mycobacteria tuberculosis in patients with urogenital tuberculosis by PCR method].

    PubMed

    Dochviri, T Z; Katsitadze, V A; Khosiashvili, G Z; Chigogidze, T G

    2005-02-01

    The study was carried out in hospital patients as well as in outpatients at the National Centre of Tuberculosis and Lung Diseases of Georgia (2002-2004). The group consisting of 32 patients with tuberculosis of urogenital system has been studied (newly detected forms). Except clinical laboratory, culture and X-ray contrast methods, two additional methods were used in testing of this group of patients. The examination of their urine, at the same time, was carried out by the Polymerase Chain Reaction method in order to detect Kochi bacillus and by three-time bacterioscopy of urine for acid resistant bacteria. Mycobacterium tuberculosis in urine has been detected in 26 (81,25%) patients by PCR method, and by urine bacterioscopy--acid fast bacilli (AFB+) in 18 (56,25%) patients. The histo-morphological investigation of specimens obtained by surgery confirmed the TB diagnosis in all patients. This study on patients suspected of Tuberculosis of genital-urinary system gives us an opportunity to update the diagnostic algorithm by including the modern molecular methods. This algorithm will help in timely detection of Tuberculosis, in selection of adequate therapy and in prevention of the further progression of the disease.

  17. Mycobacterium tuberculosis Serine/Threonine Protein Kinases

    PubMed Central

    PRISIC, SLADJANA; HUSSON, ROBERT N.

    2014-01-01

    The Mycobacterium tuberculosis genome encodes 11 serine/threonine protein kinases (STPKs). A similar number of two-component systems are also present, indicating that these two signal transduction mechanisms are both important in the adaptation of this bacterial pathogen to its environment. The M. tuberculosis phosphoproteome includes hundreds of Ser- and Thr-phosphorylated proteins that participate in all aspects of M. tuberculosis biology, supporting a critical role for the STPKs in regulating M. tuberculosis physiology. Nine of the STPKs are receptor type kinases, with an extracytoplasmic sensor domain and an intracellular kinase domain, indicating that these kinases transduce external signals. Two other STPKs are cytoplasmic and have regulatory domains that sense changes within the cell. Structural analysis of some of the STPKs has led to advances in our understanding of the mechanisms by which these STPKs are activated and regulated. Functional analysis has provided insights into the effects of phosphorylation on the activity of several proteins, but for most phosphoproteins the role of phosphorylation in regulating function is unknown. Major future challenges include characterizing the functional effects of phosphorylation for this large number of phosphoproteins, identifying the cognate STPKs for these phosphoproteins, and determining the signals that the STPKs sense. Ultimately, combining these STPK-regulated processes into larger, integrated regulatory networks will provide deeper insight into M. tuberculosis adaptive mechanisms that contribute to tuberculosis pathogenesis. Finally, the STPKs offer attractive targets for inhibitor development that may lead to new therapies for drug-susceptible and drug-resistant tuberculosis. PMID:25429354

  18. Growth hormone activation of human monocytes for superoxide production but not tumor necrosis factor production, cell adherence, or action against Mycobacterium tuberculosis.

    PubMed Central

    Warwick-Davies, J; Lowrie, D B; Cole, P J

    1995-01-01

    We have previously demonstrated that growth hormone (GH) is a human macrophage-activating factor which primes monocytes for enhanced production of H2O2 in vitro. This report extends our observations to other monocyte functions relevant to infection. We find that GH also primes monocytes for O2- production, to a degree similar to the effect of gamma interferon. Neither macrophage-activating factor alone stimulates monocytes to release bioactive tumor necrosis factor. However, GH, unlike gamma interferon, does not synergize with endotoxin for enhanced tumor necrosis factor production. In further contrast, GH does not alter monocyte adherence or morphology, while phagocytosis and killing of Mycobacterium tuberculosis by GH-treated monocytes are also unaffected. Therefore, despite the multiplicity of the effects of GH on the immune system in vivo, its effects on human monocytes in vitro appear to be limited to priming for the release of reactive oxygen intermediates. PMID:7591064

  19. Global Tuberculosis Report 2016

    MedlinePlus

    ... WHO Language عربي 中文 English Français Русский Español Tuberculosis (TB) Menu Tuberculosis The End TB Strategy Areas ... data News, events and features About us Global tuberculosis report 2016 WHO has published a global TB ...

  20. Cost-effectiveness of tuberculosis evaluation and treatment of newly-arrived immigrants

    PubMed Central

    Porco, Travis C; Lewis, Bryan; Marseille, Elliot; Grinsdale, Jennifer; Flood, Jennifer M; Royce, Sarah E

    2006-01-01

    Background Immigrants to the U.S. are required to undergo overseas screening for tuberculosis (TB), but the value of evaluation and treatment following entry to the U.S. is not well understood. We determined the cost-effectiveness of domestic follow-up of immigrants identified as tuberculosis suspects through overseas screening. Methods Using a stochastic simulation for tuberculosis reactivation, transmission, and follow-up for a hypothetical cohort of 1000 individuals, we calculated the incremental cost-effectiveness of follow-up and evaluation interventions. We utilized published literature, California Reports of Verified Cases of Tuberculosis (RVCTs), demographic estimates from the California Department of Finance, Medicare reimbursement, and Medi-Cal reimbursement rates. Our target population was legal immigrants to the United States, our time horizon is twenty years, and our perspective was that of all domestic health-care payers. We examined the intervention to offer latent tuberculosis therapy to infected individuals, to increase the yield of domestic evaluation, and to increase the starting and completion rates of LTBI therapy with INH (isoniazid). Our outcome measures were the number of cases averted, the number of deaths averted, the incremental dollar cost (year 2004), and the number of quality-adjusted life-years saved. Results Domestic follow-up of B-notification patients, including LTBI treatment for latently infected individuals, is highly cost-effective, and at times, cost-saving. B-notification follow-up in California would reduce the number of new tuberculosis cases by about 6–26 per year (out of a total of approximately 3000). Sensitivity analysis revealed that domestic follow-up remains cost-effective when the hepatitis rates due to INH therapy are over fifteen times our best estimates, when at least 0.4 percent of patients have active disease and when hospitalization of cases detected through domestic follow-up is no less likely than