keyword
MENU ▼
Read by QxMD icon Read
search

Mycobacterium tuberculosis

keyword
https://www.readbyqxmd.com/read/28436493/an-attenuated-mycobacterium-tuberculosis-clinical-strain-with-a-defect-in-esx-1-secretion-induces-minimal-host-immune-responses-and-pathology
#1
Helena Strand Clemmensen, Niels Peter Hell Knudsen, Erik Michael Rasmussen, Jessica Winkler, Ida Rosenkrands, Ahmad Ahmad, Troels Lillebaek, David R Sherman, Peter Lawætz Andersen, Claus Aagaard
Although Mycobacterium tuberculosis (M.tb) DK9897 is an attenuated strain, it was isolated from a patient with extrapulmonary tuberculosis and vaccination with a subunit vaccine (H56) induced poor protection against it. Both attenuation and lack of protection are because M.tb DK9897 cannot secrete the EsxA virulence factor nor induce a host response against it. Genome sequencing identified a frameshift mutation in the eccCa1 gene. Since the encoded EccCa1 protein provides energy for ESX-1 secretion, it suggested a defect in the ESX-1 type VII secretion system...
April 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28436453/functional-thermodynamics-structural-and-biological-studies-of-in-silico-identified-inhibitors-of-mycobacterium-tuberculosis-enoyl-acp-coa-reductase-enzyme
#2
Leonardo K B Martinelli, Mariane Rotta, Anne D Villela, Valnês S Rodrigues-Junior, Bruno L Abbadi, Rogério V Trindade, Guilherme O Petersen, Giuliano M Danesi, Laura R Nery, Ivani Pauli, Maria M Campos, Carla D Bonan, Osmar Norberto de Souza, Luiz A Basso, Diogenes S Santos
Novel chemotherapeutics agents are needed to kill Mycobacterium tuberculosis, the main causative agent of tuberculosis (TB). The M. tuberculosis 2-trans-enoyl-ACP(CoA) reductase enzyme (MtInhA) is the druggable bona fide target of isoniazid. New chemotypes were previously identified by two in silico approaches as potential ligands to MtInhA. The inhibition mode was determined by steady-state kinetics for seven compounds that inhibited MtInhA activity. Dissociation constant values at different temperatures were determined by protein fluorescence spectroscopy...
April 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28435012/il-10-down-regulates-the-expression-of-survival-associated-gene-hspx-of-mycobacterium-tuberculosis-in-murine-macrophage
#3
Babban Jee, Pawan Sharma, Kiran Katoch, Beenu Joshi, Sudhir Kumar Awasthi
Mycobacterium tuberculosis (MTB) adopts a special survival strategy to overcome the killing mechanism(s) of host immune system. Amongst the many known factors, small heat shock protein 16.3 (sHSP16.3) of MTB encoded by gene hspX has been reported to be critical for the survival of MTB. In the present study, the effect of recombinant murine interferon-gamma (rmIFN-γ) and recombinant murine interleukin-10 (rmIL-10) on the expression of gene hspX of MTB in murine macrophage RAW264.7 has been investigated. By real-time RT-PCR, it was observed that three increasing concentrations (5, 25 and 50ng/ml) of rmIFN-γ significantly up-regulated the expression of hspX whereas similar concentrations of rmIL-10 (5, 25 and 50ng/ml) significantly down-regulated the hspX expression...
April 20, 2017: Brazilian Journal of Infectious Diseases
https://www.readbyqxmd.com/read/28434972/one-bacillus-to-rule-them-all-investigating-broad-range-host-adaptation-in-mycobacterium-bovis
#4
REVIEW
Adrian R Allen
Recent advances are permitting researchers to undertake largescale comparative genomics studies within and between bacterial species to determine the types of genetic change that underpin the phenotypic spectrum that runs from strict host adaptation to generalist. Within the Mycobacterium tuberculosis complex (MTBC) of bacilli, there is much heterogeneity in host specificity. Globally, Mycobacterium bovis exhibits a broad host range encompassing domesticated bovine and wildlife animals unlike the human adapted specialist M...
April 20, 2017: Infection, Genetics and Evolution
https://www.readbyqxmd.com/read/28434937/defining-a-research-agenda-to-address-the-converging-epidemics-of-tuberculosis-and-diabetes-part-2-underlying-biological-mechanisms
#5
REVIEW
Katharina Ronacher, Reinout van Crevel, Julia Critchley, Andrew A Bremer, Larry S Schlesinger, Anil Kapur, Randall Basaraba, Hardy Kornfeld, Blanca I Restrepo
There is growing interest in the re-emerging interaction between type 2 diabetes (DM) and tuberculosis (TB), but the underlying biological mechanisms are poorly understood despite their possible implications in clinical management. Experts in epidemiological, public health, basic science and clinical studies recently convened and identified research priorities for elucidating the underlying mechanisms for the co-ocurrence of TB and DM. We identified gaps in current knowlege of altered immunity in DM patients during TB, where most studies suggest an under-performing innate immunity, but exaggerated adaptive immunity to Mycobacterium tuberculosis...
April 19, 2017: Chest
https://www.readbyqxmd.com/read/28433210/non-tuberculous-mycobacteria-an-emerging-threat
#6
Susana Martínez González, Arantxa Cano Cortés, Luis Alfonso Sota Yoldi, José María García García, Luz María Alba Álvarez, Juan José Palacios Gutiérrez
INTRODUCTION AND OBJECTIVE: Non-tuberculous mycobacteria (NTM) isolates are becoming more common. The main objective of our study was to establish the number and diversity of NTM species in our region and their distribution according to the source sample, age and gender of the patients, and to analyse clinically significant isolates. METHODOLOGY: Prospective study of all NTM isolated in Asturias from 2005 to 2012. Samples were processed following internationally accepted guidelines...
April 19, 2017: Archivos de Bronconeumología
https://www.readbyqxmd.com/read/28432345/distant-phe345-mutation-compromises-the-stability-and-activity-of-mycobacterium-tuberculosis-isocitrate-lyase-by-modulating-its-structural-flexibility
#7
Harish Shukla, Rohit Shukla, Amit Sonkar, Tripti Pandey, Timir Tripathi
Isocitrate lyase (ICL), a potential anti-tubercular drug target, catalyzes the first step of the glyoxylate shunt. In the present investigation, we studied the conformational flexibility of MtbICL to better understand its stability and catalytic activity. Our biochemical results showed that a point mutation at Phe345, which is topologically distant (>10 Å) to the active site signature sequence ((189)KKCGH(193)), completely abolishes the activity of the enzyme. In depth computational analyses were carried out for understanding the structural alterations using molecular dynamics, time-dependent secondary structure and principal component analysis...
April 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28432321/mycobacterium-tuberculosis-lineage-distribution-in-xinjiang-and-gansu-provinces-china
#8
Haixia Chen, Li He, Hairong Huang, Chengmin Shi, Xumin Ni, Guangming Dai, Liang Ma, Weimin Li
Mycobacterium tuberculosis (M. tuberculosis) genotyping has dramatically improved the understanding of the epidemiology of tuberculosis (TB). In this study, 187 M. tuberculosis isolates from Xinjiang Uygur Autonomous Region (Xinjiang) and Gansu province in China were genotyped using large sequence polymorphisms (LSPs) and variable number tandem repeats (VNTR). Ten isolates, which represent major nodes of VNTR-based minimum spanning tree, were selected and subsequently subjected to multi-locus sequence analyses (MLSA) that include 82 genes...
April 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28431548/water-pipe-smoke-condensate-increases-the-internalization-of-mycobacterium-bovis-of-type-ii-alveolar-epithelial-cells-a549
#9
Esmaeil Mortaz, Shamila D Alipoor, Masoud Movassaghi, Mohammad Varahram, Jahangir Ghorbani, Gert Folkerts, Johan Garssen, Ian M Adcock
BACKGROUND: Tuberculosis (TB) is a major global health problem, and there is an association between tobacco smoke and TB. Water pipe smoking has become an increasing problem not only in Middle Eastern countries but also globally because users consider it as safer than cigarettes. The presence of high levels of toxic substances in water-pipe smoke may be a predisposing factor that enhances the incidence of pulmonary disorders. For example, uncontrolled macropinocytosis in alveolar epithelial cells following exposure to water-pipe smoke may predispose subjects to pulmonary infection...
April 21, 2017: BMC Pulmonary Medicine
https://www.readbyqxmd.com/read/28430824/suppressors-of-cytokine-signaling-in-tuberculosis
#10
Shih-Wei Lee, Chi-Wei Liu, Jia-Ying Hu, Li-Mei Chiang, Chih-Pin Chuu, Lawrence Shih-Hsin Wu, Yung-Hsi Kao
Tuberculosis (TB), a global disease mainly infected by Mycobacterium tuberculosis, remains leading public health problem worldwide. Suppressors of cytokine signaling (SOCSs) play important roles in the protection against microbial infection. However, the relationship between members of the SOCS family and tuberculosis infection remains unclear. Using peripheral blood mononuclear cells, we investigated the mRNA expression profiles of SOCS subfamilies among active TB, latent tuberculosis infection (LTBI), and healthy individuals...
2017: PloS One
https://www.readbyqxmd.com/read/28430807/diagnosis-of-smear-negative-tuberculosis-is-greatly-improved-by-xpert-mtb-rif
#11
Giulia Lombardi, Valentina Di Gregori, Nicolò Girometti, Marina Tadolini, Francesco Bisognin, Paola Dal Monte
BACKGROUND: Diagnosis of pulmonary (PTB) and extra-pulmonary tuberculosis (EPTB) in smear-negative patients can be difficult. We assessed retrospectively the performance of Xpert MTB/RIF system (Xpert, Cepheid) in diagnosing smear-negative tuberculosis (TB), which represents the most common form of TB in a low incidence setting. METHODS: Performance of Xpert was compared to acid-fast microscopic examination using Ziehl-Neelsen (ZN) stain in patients with culture-confirmed TB...
2017: PloS One
https://www.readbyqxmd.com/read/28429168/bedaquiline-susceptibility-test-for-totally-drug-resistant-tuberculosis-mycobacterium-tuberculosis
#12
Ji-Chan Jang, Yong-Gyun Jung, Jungil Choi, Hyunju Jung, Sungweon Ryoo
This study aimed to provide information that bedaquilline is significantly effective for treatment of totally drug resistant (TDR) Mycobacterium tuberculosis that shows resistant to all first- and second-line drugs-using an innovative disc agarose channel (DAC) system. Time-lapse images of single bacterial cells under culture conditions with different concentrations of bedaquiline were analysed by image processing software to determine minimum inhibitory concentrations (MICs). Bedaquiline inhibited the growth of TDR M...
April 20, 2017: Journal of Microbiology / the Microbiological Society of Korea
https://www.readbyqxmd.com/read/28429162/involvement-of-methylated-hbha-expressed-from-mycobacterium-smegmatis-in-an-ifn-%C3%AE-release-assay-to-aid-discrimination-between-latent-infection-and-active-tuberculosis-in-bcg-vaccinated-populations
#13
H-L Wen, C-L Li, G Li, Y-H Lu, H-C Li, T Li, H-M Zhao, K Wu, D B Lowrie, J-X Lv, S-H Lu, X-Y Fan
IFN-γ release assays (IGRAs) based on region of difference 1 (RD1) antigens have improved diagnosis of Mycobacterium tuberculosis (M. tb) infection. However, IGRAs with these antigens cannot discriminate between active tuberculosis (ATB) and latent tuberculosis infection (LTBI). M. tb heparin-binding-hemagglutinin (HBHA) induces relatively high IFN-γ responses in LTBI individuals and low responses in ATB patients, but purification of the native methylated HBHA from cultures of M. tb for immunological tests is complex and time-consuming...
April 20, 2017: European Journal of Clinical Microbiology & Infectious Diseases
https://www.readbyqxmd.com/read/28428773/mutation-at-g103-of-mtbftsz-altered-their-sensitivity-to-coumarins
#14
Duggirala Sridevi, Karpagam U Sudhakar, Ragamanvitha Ananthathatmula, Rakesh P Nankar, Mukesh Doble
Coumarins are natural polyphenol lactones comprising of fused rings of benzene and α-pyrone. The current study demonstrates the inhibitory effect of coumarins with various substitutions on Mycobacterium smegmatis mc(2) 155. We also demonstrate the effect of pomegranate (Punica granatum) extract containing ellagic acid, on M. smegmatis as well as their affect on MtbFtsZ (FtsZ from Mycobacterium tuberculosis). The ellagic acid extracts from pomegranate peels inhibit mycobacteria with a MIC of 25 μM and 0.3 to 3...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28428201/dihydrolipoamide-dehydrogenase-lpd-rv0462-specific-t-cell-recall-responses-are-higher-in-healthy-household-contacts-of-tb-a-novel-immunodominant-antigen-from-m-tuberculosis
#15
Santhi Devasundaram, Alamelu Raja
The partial effectiveness against pulmonary tuberculosis (PTB), displayed by the existing tuberculosis (TB) vaccine, bacillus Calmette-Guérin (BCG), highlights the need for novel vaccines to replace or improve BCG. In TB immunology, antigen-specific cellular immune response is frequently considered indispensable. Latency-associated antigens are intriguing as targets for TB vaccine development. The mycobacterial protein, dihydrolipoamide dehydrogenase (Lpd; Rv0462), the third enzyme of the pyruvate dehydrogenase (PDH) complex, facilitates Mycobacterium tuberculosis to resist host reactive nitrogen intermediates...
April 20, 2017: Journal of Leukocyte Biology
https://www.readbyqxmd.com/read/28427611/experimental-study-on-the-influence-of-low-frequency-and-low-intensity-ultrasound-on-the-permeability-of-the-mycobacterium-smegmatis-cytoderm-and-potentiation-with-levofloxacin
#16
Yu Dong, Hang Su, Hexun Jiang, Huimin Zheng, Yonghong Du, Junru Wu, Dairong Li
Tuberculosis is an infectious disease caused by the bacterium M. tuberculosis. The aim of this study was to investigate the bactericidal effect and underlying mechanisms of low-frequency and low-intensity ultrasound combined with levofloxacin treatment against M. smegmatis (a surrogate of M. tuberculosis). As part of this study, M. smegmatis was continuously irradiated with low frequency ultrasound (42kHz) using several different doses whereby both intensity (0.138, 0.190 and 0.329W/cm(2)) and exposure time (5, 15 and 20min) were varied...
July 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28427163/the-application-of-is6110-baced-loop-mediated-isothermal-amplification-lamp-in-the-early-diagnosis-of-tuberculous-meningitis
#17
Wen-Wen Sun, Qin Sun, Li-Ping Yan, Qing Zhang
Here, we evaluated the potential activity of rapid Mycobacterium tuberculosis detection with loop-mediated isothermal amplification (LAMP), for the early diagnosis of tuberculous meningitis (TBM). Patients with suspected TBM from January 2014 to December 2015 were reviewed retrospectively. The cerebrospinalfluid(CSF) was collected. Acid-fast bacillus (AFB) staining, MGIT 960 culture, real-time fluorescent quantitative polymerase chain reaction (RTFQ PCR) and LAMP were performed. A total of 200 patients were included in the study...
February 25, 2017: Oncotarget
https://www.readbyqxmd.com/read/28427007/novel-and-revisited-approaches-in-antituberculosis-drug-discovery
#18
REVIEW
Jennifer Herrmann, Jan Rybniker, Rolf Müller
The increasing prevalence of multidrug-resistant Mycobacterium tuberculosis (Mtb) necessitates the discovery and development of novel drugs against tuberculosis. In this review, we focus on two recent approaches that led to the discovery of promising antitubercular compound classes: (I) Hits derived from large compound library screens are increasingly difficult to translate into clinical application; this in turn fostered the development of innovative screening methods. (II) An alternative strategy towards high-quality hits and leads is to evaluate chemically diverse scaffolds which can be found among natural products...
April 17, 2017: Current Opinion in Biotechnology
https://www.readbyqxmd.com/read/28426273/preclinical-development-of-bcg-hiva-2auxo-int-harboring-an-integrative-expression-vector-for-a-hiv-tb-pediatric-vaccine-enhancement-of-stability-and-specific-hiv-1-t-cell-immunity
#19
Aakash Mahant, Narcís Saubi, Yoshiki Eto, Núria Guitart, Josep M ª Gatell, Tomáš Hanke, Joan Joseph
One of the critical issues that should be addressed in the development of a BCG-based HIV vaccine is genetic plasmid stability. Therefore, to address this issue we have considered using integrative vectors and the auxotrophic mutant of BCG complemented with a plasmid carrying a wild-type complementing gene. In this study, we have constructed an integrative E. coli-mycobacterial shuttle plasmid, p2auxo.HIVA(int), expressing the HIV-1 clade A immunogen HIVA. This shuttle vector employs an antibiotic resistance-free mechanism for plasmid selection and maintenance...
April 20, 2017: Human Vaccines & Immunotherapeutics
https://www.readbyqxmd.com/read/28425873/rapid-detection-of-mycobacterium-tuberculosis-and-rifampicin-resistance-in-extrapulmonary-tuberculosis-and-sputum-smear-negative-pulmonary-suspects-using-xpert-mtb-rif
#20
Irfan Ullah, Arshad Javaid, Haleema Masud, Mazhar Ali, Anila Basit, Waqas Ahmad, Faisal Younis, Rehana Yasmin, Afsar Khan, Abdul Jabbar, Masroor Husain, Zahid Ahmad Butt
BACKGROUND: Tuberculosis (TB) is a serious public health problem in developing countries such as Pakistan. Rapid diagnosis of TB and detection of drug resistance are very important for timely and appropriate management of multidrug-resistant TB (MDR-TB). OBJECTIVE: The purpose of this study was to determine the diagnostic efficacy of the Xpert MTB/RIF assay for rapid diagnosis of TB and detection of rifampicin (RIF) resistance in extrapulmonary and smear-negative pulmonary TB suspects...
April 21, 2017: Journal of Medical Microbiology
keyword
keyword
15628
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"