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2.
J Enzyme Inhib Med Chem ; 35(1): 65-71, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31663386

RESUMO

We investigated a panel of 14 compounds belonging to the monothiocarbamate (MTC) and dithiocarbamate (DTC) series against the ß-carbonic anhydrase 3 (ß-CA3) of Mycobacterium tuberculosis (Mtb). We also evaluated all compounds for toxicity using 1-5-day post fertilisation zebrafish embryos. 11 out of the 14 investigated derivatives showed effective nanomolar or submicromolar in vitro inhibition against the ß-CA3 (KIs 2.4-812.0 nM), and among them four DTCs of the series (8-10 and 12) showed very significant inhibition potencies with KIs between 2.4 and 43 nM. Out of 14 compounds screened for toxicity and safety 9 compounds showed no adverse phenotypic effects on the developing zebrafish larvae at five days of exposure. The results of in vitro inhibition and the toxicological evaluation of our study suggest that 5 compounds are suitable for further in vivo preclinical characterisation in zebrafish model.


Assuntos
Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Mycobacterium tuberculosis/efeitos dos fármacos , Animais , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Relação Dose-Resposta a Droga , Estrutura Molecular , Mycobacterium tuberculosis/enzimologia , Relação Estrutura-Atividade , Peixe-Zebra
3.
J Enzyme Inhib Med Chem ; 34(1): 1730-1739, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31822127

RESUMO

A series of readily accessible 1-(piperidin-3-yl)thymine amides was designed, synthesised and evaluated as Mycobacterium tuberculosis TMPK (MtbTMPK) inhibitors. In line with the modelling results, most inhibitors showed reasonable MtbTMPK inhibitory activity. Compounds 4b and 4i were slightly more potent than the parent compound 3. Moreover, contrary to the latter, amide analogue 4g was active against the avirulent M. tuberculosis H37Ra strain (MIC50=35 µM). This finding opens avenues for future modifications.


Assuntos
Amidas/farmacologia , Antituberculosos/farmacologia , Inibidores Enzimáticos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Núcleosídeo-Fosfato Quinase/antagonistas & inibidores , Timina/farmacologia , Amidas/síntese química , Amidas/química , Antituberculosos/síntese química , Antituberculosos/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium tuberculosis/enzimologia , Núcleosídeo-Fosfato Quinase/metabolismo , Relação Estrutura-Atividade , Timina/síntese química , Timina/química
4.
BMC Infect Dis ; 19(1): 1047, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823734

RESUMO

BACKGROUND: Molecular tests can allow the rapid detection of tuberculosis (TB) and multidrug-resistant TB (MDR-TB). TB-SPRINT 59-Plex Beamedex® is a microbead-based assay developed for the simultaneous spoligotyping and detection of MDR-TB. The accuracy and cost evaluation of new assays and technologies are of great importance for their routine use in clinics and in research laboratories. The aim of this study was to evaluate the performance of TB-SPRINT at three laboratory research centers in Brazil and calculate its mean cost (MC) and activity-based costing (ABC). METHODS: TB-SPRINT data were compared with the phenotypic and genotypic profiles obtained using Bactec™ MGIT™ 960 system and Genotype® MTBDRplus, respectively. RESULTS: Compared with MGIT, the accuracies of TB-SPRINT for the detection of rifampicin and isoniazid resistance ranged from 81 to 92% and 91.3 to 93.9%, respectively. Compared with MTBDRplus, the accuracies of TB-SPRINT for rifampicin and isoniazid were 99 and 94.2%, respectively. Moreover, the MC and ABC of TB-SPRINT were USD 127.78 and USD 109.94, respectively. CONCLUSION: TB-SPRINT showed good results for isoniazid and rifampicin resistance detection, but still needs improvement to achieve In Vitro Diagnostics standards.


Assuntos
Farmacorresistência Bacteriana , Citometria de Fluxo/métodos , Mycobacterium tuberculosis/genética , Tuberculose/diagnóstico , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Catalase/genética , Custos e Análise de Custo , RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Citometria de Fluxo/economia , Genótipo , Humanos , Isoniazida/farmacologia , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Regiões Promotoras Genéticas , Kit de Reagentes para Diagnóstico , Rifampina , Sensibilidade e Especificidade , Tuberculose/economia
5.
BMC Bioinformatics ; 20(1): 603, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752678

RESUMO

BACKGROUND: Deep sequencing of transposon mutant libraries (or TnSeq) is a powerful method for probing essentiality of genomic loci under different environmental conditions. Various analytical methods have been described for identifying conditionally essential genes whose tolerance for insertions varies between two conditions. However, for large-scale experiments involving many conditions, a method is needed for identifying genes that exhibit significant variability in insertions across multiple conditions. RESULTS: In this paper, we introduce a novel statistical method for identifying genes with significant variability of insertion counts across multiple conditions based on Zero-Inflated Negative Binomial (ZINB) regression. Using likelihood ratio tests, we show that the ZINB distribution fits TnSeq data better than either ANOVA or a Negative Binomial (in a generalized linear model). We use ZINB regression to identify genes required for infection of M. tuberculosis H37Rv in C57BL/6 mice. We also use ZINB to perform a analysis of genes conditionally essential in H37Rv cultures exposed to multiple antibiotics. CONCLUSIONS: Our results show that, not only does ZINB generally identify most of the genes found by pairwise resampling (and vastly out-performs ANOVA), but it also identifies additional genes where variability is detectable only when the magnitudes of insertion counts are treated separately from local differences in saturation, as in the ZINB model.


Assuntos
Elementos de DNA Transponíveis/genética , Bases de Dados Genéticas , Sequenciamento de Nucleotídeos em Larga Escala , Modelos Estatísticos , Animais , Antibacterianos/farmacologia , Distribuição Binomial , Genes Essenciais , Funções Verossimilhança , Modelos Lineares , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética
6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(5): 629-634, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31762229

RESUMO

OBJECTIVE: To establish a way for screening Mycobacterium mutants through adding the screening markers into pJV53. METHODS: The sucrose counter selection gene SacB and mutant hygromycin-resistant gene hygS were inserted into pJV53; The recovery of the hygromycin-resistance indicated the successful homologous recombination in Mycobacterium smegmatis (Ms), which could serve as mutant screening marker; The sucrose counter selection could be used to screen the plasmid-free mutants. RESULTS: The recombinant plasmid pJV53-SacB-hygS were successfully constructed. The rifampin-resistant rpoB D516Y and rpoB H526Q mutants and MSMEG_4487 G188A mutant were efficiently screened out. All mutants had shed the plasmid successfully. CONCLUSION: pJV53-SacB-hygS can efficiently contribute to construct and screen the mutants and to get the mutants shedding the plasmid self, which has high value of extensive application; the D516Y and H526Q mutations in gene rpoB of Mycobacterium tuberculosis contribute to its rifampin-resistance.


Assuntos
Farmacorresistência Bacteriana/genética , Recombinação Homóloga , Mycobacterium smegmatis/genética , Mycobacterium tuberculosis/genética , Proteínas de Bactérias/genética , RNA Polimerases Dirigidas por DNA/genética , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/efeitos dos fármacos , Plasmídeos/genética , Rifampina/farmacologia
7.
BMJ ; 367: l5894, 2019 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-31649017

RESUMO

OBJECTIVE: To measure the association between phenotypic drug resistance and the risk of tuberculosis infection and disease among household contacts of patients with pulmonary tuberculosis. SETTING: 106 district health centers in Lima, Peru between September 2009 and September 2012. DESIGN: Prospective cohort study. PARTICIPANTS: 10 160 household contacts of 3339 index patients with tuberculosis were classified on the basis of the drug resistance profile of the patient: 6189 were exposed to drug susceptible strains of Mycobacterium tuberculosis, 1659 to strains resistant to isoniazid or rifampicin, and 1541 to strains that were multidrug resistant (resistant to isoniazid and rifampicin). MAIN OUTCOME MEASURES: Tuberculosis infection (positive tuberculin skin test) and the incidence of active disease (diagnosed by positive sputum smear or chest radiograph) after 12 months of follow-up. RESULTS: Household contacts exposed to patients with multidrug resistant tuberculosis had an 8% (95% confidence interval 4% to 13%) higher risk of infection by the end of follow-up compared with household contacts of patients with drug sensitive tuberculosis. The relative hazard of incident tuberculosis disease did not differ among household contacts exposed to multidrug resistant tuberculosis and those exposed to drug sensitive tuberculosis (adjusted hazard ratio 1.28, 95% confidence interval 0.9 to 1.83). CONCLUSION: Household contacts of patients with multidrug resistant tuberculosis were at higher risk of tuberculosis infection than contacts exposed to drug sensitive tuberculosis. The risk of developing tuberculosis disease did not differ among contacts in both groups. The evidence invites guideline producers to take action by targeting drug resistant and drug sensitive tuberculosis, such as early detection and effective treatment of infection and disease. TRIAL REGISTRATION: ClinicalTrials.gov NCT00676754.


Assuntos
Tuberculose Resistente a Múltiplos Medicamentos/transmissão , Tuberculose Pulmonar/transmissão , Adolescente , Adulto , Idoso , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Criança , Pré-Escolar , Busca de Comunicante/métodos , Progressão da Doença , Feminino , Seguimentos , Humanos , Incidência , Lactente , Recém-Nascido , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Estimativa de Kaplan-Meier , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Peru/epidemiologia , Estudos Prospectivos , Rifampina/farmacologia , Rifampina/uso terapêutico , Escarro/microbiologia , Teste Tuberculínico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/microbiologia , Adulto Jovem
8.
Pharm Res ; 36(12): 166, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31650321

RESUMO

The discovery of drugs to treat tuberculosis (TB) was a major medical milestone in the twentieth century. However, from the outset, drug resistance was observed. Currently, of the 10 million people that exhibit TB symptoms each year, 450,000 have multidrug or extensively drug resistant (MDR or XDR) TB. While greater understanding of the host and pathogen (Mycobacterium tuberculosis, Mtb) coupled with scientific ingenuity will lead to new drugs and vaccines, in the meantime 4000 people die daily from TB. Thus, efforts to improve existing TB drugs should also be prioritized. Improved efficacy and decreased dose and associated toxicity of existing drugs would translate to greater compliance, life expectancy and quality of life of Mtb infected individuals. One potential strategy to improve existing drugs is to deliver them by inhalation as aerosols to the lung, the primary site of Mtb infection. Inhaled drugs are used for other pulmonary diseases, but they have yet to be utilized for TB. Inhaled therapies for TB represent an untapped opportunity that the pharmaceutical, clinical and regulatory communities should consider.


Assuntos
Antituberculosos/administração & dosagem , Tuberculose/tratamento farmacológico , Administração por Inalação , Aerossóis/química , Antituberculosos/efeitos adversos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Resistência a Múltiplos Medicamentos , Humanos , Pulmão , Mycobacterium tuberculosis/efeitos dos fármacos , Nebulizadores e Vaporizadores
9.
Org Biomol Chem ; 17(43): 9524-9528, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31659363

RESUMO

Dimeric benzoboroxoles that are covalently linked by a short scaffold enhance selective anti-tubercular activity. These multimeric benzoboroxole compounds are capable of engaging the specific extracellular Mycobacterium tuberculosis glycans, do not lead to the evolution of resistance and bypass the need to cross the impermeable mycobacterial cell envelope barrier.


Assuntos
Antituberculosos/farmacologia , Ácidos Borônicos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Células A549 , Antituberculosos/síntese química , Antituberculosos/química , Ácidos Borônicos/síntese química , Ácidos Borônicos/química , Dimerização , Eritrócitos , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular
10.
Comput Biol Chem ; 83: 107136, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31630014

RESUMO

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb). In the present age, due to the rapid increase in antibiotic resistance worldwide, TB has become a major threat to human life. Regardless of significant efforts have been inclined to improve the healthcare systems for improving diagnosis, treatment, and anticipatory measures controlling TB is challenging. To date, there are no such therapeutic chemical agents available to fight or control the bacterial drug-resistance. The catalase-peroxidase enzyme (katG) which encoded by the katG gene of Mtb is most frequently getting mutated and hence promotes Isoniazid resistance by diminishing the normal activity of katG enzyme. In the current study, an effort has been intended to find novel and therapeutically active antibacterial chemical compounds through pharmacoinformatics methodologies. Initially, the five mutant katG were generated by making mutation of Ser315 by Thr, Ile, Arg, Asn, and Gly followed by structural optimizations. About eight thousand small molecules were collected from the Asinex antibacterial library. All molecules were docked to active site of five mutant katG and wild type katG. To narrow down the chemical space several criteria were imposed including, screening for highest binding affinity towards katG proteins, compounds satisfying various criterion of drug-likeliness properties like Lipinski's rule of five (RO5), Veber's rule, absorption, distribution, metabolism, and excretion (ADME) profile, and synthetic accessibility. Finally, five molecules were found to be important antibacterial katG inhibitors. All the analyzed parameters suggested that selected molecules are promising in nature. Binding interactions analysis revealed that proposed molecules are efficient enough to form a number of strong binding interactions with katG proteins. Dynamic behavior of the proposed molecules with katG protein was evaluated through 100 ns molecular dynamics (MD) simulation study. Parameters calculated from the MD simulation trajectories adjudged that all molecules can form stable complexes with katG. High binding free energy of all proposed molecules definitely suggested strong affection towards the katG. Hence, it can be concluded that proposed molecules might be used as antibacterial chemical component subjected to experimental validation.


Assuntos
Antituberculosos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/enzimologia , Peroxidases/antagonistas & inibidores , Antituberculosos/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Inibidores Enzimáticos/química , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peroxidases/genética , Peroxidases/metabolismo
11.
J Med Microbiol ; 68(11): 1622-1628, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31596198

RESUMO

Introduction. Nosocomial transmission of Mycobacterium tuberculosis is an important health issue and the detection of tuberculosis (TB) cases is the main tool for controlling this disease.Aim. We aimed to assess the possible occurrence of nosocomial transmission of M. tuberculosis in a reference hospital for HIV/AIDS patients and evaluate both the performance of the Xpert MTB/RIF (Xpert) platform and drug resistance profiles.Methodology. We evaluated the performance of the Xpert platform. Samples that tested positive on the BACTEC MGIT 320 (MGIT320) platform were submitted for genotyping and drug susceptibility testing.Results. In this study, pulmonary and extrapulmonary samples from 407 patients were evaluated, and among these, 15.5 % were diagnosed with TB by the MGIT320 platform, with a TB/HIV coinfection rate of 52.4 %. The Xpert platform gave positive results for TB for 11 samples with negative results on the MGIT320 platform. In the genotyping results, 53.3 % of the strains clustered; of these strains, half were in two of the four clusters formed, and the patients had visited the hospital on the same day. Drug resistance was observed in 11.7 % of the strains.Conclusion. Putative nosocomial transmission of M. tuberculosis was detected, showing that genotyping is a powerful approach for understanding the dynamics of M. tuberculosis transmission, especially in a high-burden TB and HIV landscape.


Assuntos
Infecções por HIV/complicações , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Pulmonar/microbiologia , Síndrome de Imunodeficiência Adquirida/complicações , Antibióticos Antituberculose/farmacologia , Técnicas de Laboratório Clínico , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/microbiologia , Estudos Transversais , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Filogenia , Tuberculose , Tuberculose Pulmonar/diagnóstico
12.
EMBO J ; 38(22): e101876, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31583725

RESUMO

Clonal microbial populations are inherently heterogeneous, and this diversification is often considered as an adaptation strategy. In clinical infections, phenotypic diversity is found to be associated with drug tolerance, which in turn could evolve into genetic resistance. Mycobacterium tuberculosis, which ranks among the top ten causes of mortality with high incidence of drug-resistant infections, exhibits considerable phenotypic diversity. In this study, we quantitatively analyze the cellular dynamics of DNA damage responses in mycobacteria using microfluidics and live-cell fluorescence imaging. We show that individual cells growing under optimal conditions experience sporadic DNA-damaging events manifested by RecA expression pulses. Single-cell responses to these events occur as transient pulses of fluorescence expression, which are dependent on the gene-network structure but are triggered by extrinsic signals. We demonstrate that preexisting subpopulations, with discrete levels of DNA damage response, are associated with differential susceptibility to fluoroquinolones. Our findings reveal that the extent of DNA integrity prior to drug exposure impacts the drug activity against mycobacteria, with conceivable therapeutic implications.


Assuntos
Proteínas de Bactérias/metabolismo , Ciprofloxacino/farmacologia , Dano ao DNA/genética , Mycobacterium tuberculosis/genética , Análise de Célula Única , Estresse Fisiológico , Tuberculose/patologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Dano ao DNA/efeitos dos fármacos , Humanos , Microfluídica , Mycobacterium tuberculosis/efeitos dos fármacos , Recombinases Rec A/genética , Recombinases Rec A/metabolismo , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia
13.
SAR QSAR Environ Res ; 30(11): 775-800, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31607177

RESUMO

Mycobacterium tuberculosis DNA gyrase subunit B (GyrB) has been identified as a promising target for rational drug design against fluoroquinolone drug-resistant tuberculosis. In this study, we attempted to identify the key structural feature for highly potent GyrB inhibitors through 2D-QSAR using HQSAR, 3D-QSAR using CoMSIA and molecular dynamics (MD) simulations approaches on a series of thiazole urea core derivatives. The best HQSAR and CoMSIA models based on IC50 and MIC displayed the structural basis required for good activity against both GyrB enzyme and mycobacterial cell. MD simulations and binding free energy analysis using MM-GBSA and waterswap calculations revealed that the urea core of inhibitors has the strongest interaction with Asp79 via hydrogen bond interactions. In addition, cation-pi interaction and hydrophobic interactions of the R2 substituent with Arg82 and Arg141 help to enhance the binding affinity in the GyrB ATPase binding site. Thus, the present study provides crucial structural features and a structural concept for rational design of novel DNA gyrase inhibitors with improved biological activities against both enzyme and mycobacterial cell, and with good pharmacokinetic properties and drug safety profiles.


Assuntos
Antituberculosos/química , Proteínas de Bactérias/química , DNA Girase/química , Desenho de Drogas , Simulação de Dinâmica Molecular , Mycobacterium tuberculosis/enzimologia , Inibidores da Topoisomerase II/química , Antituberculosos/farmacologia , Sítios de Ligação , Simulação por Computador , Ligações de Hidrogênio , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Relação Quantitativa Estrutura-Atividade , Inibidores da Topoisomerase II/farmacologia
14.
Nat Commun ; 10(1): 4177, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519879

RESUMO

Drug resistant infections represent one of the most challenging medical problems of our time. D-cycloserine is an antibiotic used for six decades without significant appearance and dissemination of antibiotic resistant strains, making it an ideal model compound to understand what drives resistance evasion. We therefore investigated why Mycobacterium tuberculosis fails to become resistant to D-cycloserine. To address this question, we employed a combination of bacterial genetics, genomics, biochemistry and fitness analysis in vitro, in macrophages and in mice. Altogether, our results suggest that the ultra-low rate of emergence of D-cycloserine resistance mutations is the dominant biological factor delaying the appearance of clinical resistance to this antibiotic. Furthermore, we also identified potential compensatory mechanisms able to minimize the severe fitness costs of primary D-cycloserine resistance conferring mutations.


Assuntos
Ciclosserina/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/metabolismo , Animais , Antibióticos Antituberculose/farmacologia , Western Blotting , Farmacorresistência Bacteriana/genética , Genótipo , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Mutação/genética , Mycobacterium tuberculosis/genética
15.
Eur J Med Chem ; 183: 111713, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31557610

RESUMO

Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) has become the world's leading killer disease due to a single infectious agent which survives in the host macrophage for the indefinite period. Hence, it is necessary to enhance the efficacy of the clinically existing antitubercular agents or to discover new anti antitubercular agents. Here, we report the synthesis, characterization and antimycobacterial evaluation of protein-drug conjugates. A carrier protein, Transferrin (Tf) was covalently conjugated to isoniazid (INH) utilizing hydrazone and amide linkers. The purity of the reactions was confirmed by SDS-PAGE while conjugation was confirmed by UV-visible spectrophotometry, MALDI-TOF analysis, and FTIR spectrophotometry. The in vitro antitubercular assay result showed that the inhibitory activity of the parent drug was conserved in both the conjugates. The conjugates were effective against intracellular Mtb H37Rv and were devoid of cytotoxic effect at therapeutic concentration.


Assuntos
Antituberculosos , Isoniazida , Mycobacterium tuberculosis/efeitos dos fármacos , Transferrina , Tuberculose/tratamento farmacológico , Antituberculosos/síntese química , Antituberculosos/farmacologia , Estabilidade de Medicamentos , Humanos , Isoniazida/síntese química , Isoniazida/química , Isoniazida/farmacologia , Testes de Sensibilidade Microbiana , Transferrina/química , Tuberculose/microbiologia
16.
Int J Mycobacteriol ; 8(3): 211-217, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31512595

RESUMO

Background: This study explored the genetic diversity of Mycobacterium tuberculosis isolates in Egypt by spoligotyping in combination with pncA gene sequencing, spoNC. Methods: First, isolates were selected from 400 isolates positive for M. tuberculosis that referred to Central Labs Ministry of Health and then were subjected to the study analyses. Results: Twenty one isolates were found to be multidrug resistant (MDR) and 29 isolates were sensitive for isonizide (INH) and rifampicine (RIF) after testing by phenotypic drug susceptibility testing (DST) and Mycobacteria Growth Indicator Tube (MGIT). Spoligotyping yielded 45 patterns belonging to seven families that previously reported in neighboring countries such as Iraq, Syria, Iran, and Turkey. While four isolates were orphans. Conclusion: Application of spoNC on obtained spoligotype patterns enhances to reduce the clustering rate. Bejing family the predominant (34%) were subdivided by pncA sequence into three sensitive DST pncA wild type, three MDR-DST isolates showing cys14Arg mutation in pncA, two sensitive DST isolates with pncA Gly97Asp mutation, and three sensitive DST pncAVal128Gly mutation. The next most common CASI_DELHI family (16%) were subdivided by pncA sequencing into CASI_DELHI (st 381, MDR) including two pncA silent mutation ser65ser (tcc > tct) and CASI_DELHI (st26, sensitive) which included six pncA (wild-type) results, and Latin-American-Mediterranean 6 family (6%) all had PncA Gly97Asp mutation. We concluded that spoNC provides good snap shot for MDR surveillance and its country origin and performs early identification of outbreaks in Egypt.


Assuntos
Amidoidrolases/genética , Mutação , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adolescente , Adulto , Idoso , Antituberculosos/farmacologia , Técnicas de Tipagem Bacteriana , Egito , Monitoramento Epidemiológico , Feminino , Variação Genética , Genótipo , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Estudos Prospectivos , Pirazinamida/farmacologia , Rifampina/farmacologia , Análise de Sequência de DNA , Escarro/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Adulto Jovem
17.
Int J Mycobacteriol ; 8(3): 223-228, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31512597

RESUMO

Background: Argentina is considered a country with a middle tuberculosis (TB) incidence. However, according to the last national epidemiological report released in 2018, since 2013, the trends are steadily increasing. The aims of this study were to determine the drug-resistance (DR), multi-DR and extensively DR (MDR/XDR-TB), and rifampicin resistance (RIF-R) burden as a part of the local TB diagnosis (June 2010-August 2018); to detect the mutations associated to isoniazid (INH) and RIF-R and their geographical distribution; and to analyze the lineage relationship among the genetic patterns of the isolates circulating in the community. Methods: Respiratory and extrapulmonary specimens were processed by Ziehl-Neelsen stain and cultured on specific media. Drug-susceptibility testing of isolates was performed by the MGIT 960 and a colorimetric micro-method. Mutations conferring DR were detected by Genotype and DNA sequencing. Results: The study showed a DR-TB prevalence of approximately 20% of the isolated strains, while M/XDR-TB-and particularly RIF-R-affected more than 5.0% of the total amount of cases. DR geographical distribution revealed isolates carrying mutations in the inhA gene promoter region only constrained to three districts where it was also registered two same family relatives' cases with the infrequent rpoB S522 L/Q mutation. The fact that most DR/MDR-TB isolates were not grouped in genetic clusters suggested that these cases may mostly have occurred due to endogenous reactivation rather than recently transmission. Conclusion: According to the obtained results, it would be convenient, in highly MDR-TB suspected individuals, to confirm phenotypically, the INH and RIF susceptibility detected by molecular tests.


Assuntos
Antituberculosos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Argentina/epidemiologia , Proteínas de Bactérias/genética , Monitoramento Epidemiológico , Tuberculose Extensivamente Resistente a Medicamentos/epidemiologia , Genótipo , Geografia , Hospitais , Humanos , Isoniazida/farmacologia , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/isolamento & purificação , Rifampina/farmacologia , Análise de Sequência de DNA , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia
18.
Int J Mycobacteriol ; 8(3): 237-243, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31512599

RESUMO

Background: Extrapulmonary tuberculosis (EPTB), accounting for 10%-20% of all cases of tuberculosis (TB), is known to be determined by host immunity. However, the contribution of bacterial factors to the development of EPTB has not been studied extensively. Mycolic acids are predominant lipids constituting the cell wall of Mycobacterium tuberculosis, and keto-mycolic acid is involved in the synthesis of foamy macrophages that facilitate persistence of mycobacteria. Hence, the present study was performed to gain an insight into variable expression of mycolic acids in clinical isolates of M. tuberculosis under stress. Methods: Pansusceptible clinical isolates of M. tuberculosis from patients with lymph node TB (LNTB) (n = 10) and pulmonary TB (PTB) (n = 10) were subjected to sodium dodecyl sulfate (SDS) stress, and the expression of mycolic acid and its biosynthetic genes was compared. Any bias arising due to the genotype of the clinical isolates was ruled out by performing single-nucleotide polymorphism cluster grouping (SCG), wherein no significant difference was observed between the SCG of LNTB or PTB isolates. Results: The expression of α-mycolic acid during the exposure to SDS was high in 7/10 (70%) LNTB and 6/10 (60%) PTB isolates. Methoxy mycolic acid showed an increased expression in 7/10 (70%) LNTB isolates and 4/10 (40%) PTB isolates. Increased expression of keto-mycolic acid on exposure with SDS was observed in 8/10 (80%) M. tuberculosis LNTB and 3/10 (30%) PTB isolates. Similarly, the mycolic acid synthesis gene, fas, was upregulated more in LNTB isolates than PTB isolates in vitro and ex vivo. SCG 3a was the most common SCG observed in 40% (8/20) of the isolates, followed by SCG 3b in 30% (6/20) of the isolates. There was no significant difference between the SCG of LNTB or PTB isolates. Conclusion: The higher expression of keto-mycolic acid in LNTB as against PTB isolates may indicate better survival in LNTB isolates in the presence of stress.


Assuntos
Expressão Gênica/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Ácidos Micólicos/metabolismo , Proteínas de Bactérias/genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Dodecilsulfato de Sódio/farmacologia , Estresse Fisiológico , Células THP-1 , Tuberculose dos Linfonodos/microbiologia , Tuberculose Pulmonar/microbiologia
19.
Int J Mycobacteriol ; 8(3): 252-261, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31512601

RESUMO

Background: The increasing incidence of multidrug-resistant cases of tuberculosis (TB) and difficulty in treating these cases requires an urgent need to find an effective anti-TB drug. There are many phytochemicals with reported antibacterial and antitubercular activities. Instead of targeting only a single target of Mycobacterium tuberculosis (MTB), this study aims to identify phytochemicals targeting multiple drug targets of MTB through subtractive genomic/proteomic approach followed by in silico screening of phytochemicals with reported anti-TB activity. Methods: Of 614 essential genes of MTB reported in database of essential genes, 15 gene products were selected using different bioinformatic resources and tools such as PANTHER, Venny, NCBI, and BLAST. Results: Virtual screening analysis of these selected drug targets against identified 148 phytochemicals revealed that amentoflavone, carpaine, 13'bromo-tiliacorinine, and 2'nortiliacorinine, able to inhibit more than one target of MTB. Conclusion: These selected compounds may be proposed as potential inhibitors of MTB and need to be tested in TB culture studies in vitro to assess their anti-TB activity.


Assuntos
Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Descoberta de Drogas , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Compostos Fitoquímicos/farmacologia , Antituberculosos/isolamento & purificação , Biologia Computacional , Simulação por Computador , Genômica , Compostos Fitoquímicos/isolamento & purificação , Proteômica , Tuberculose/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
20.
Int J Mycobacteriol ; 8(3): 287-291, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31512606

RESUMO

Background: While, bacteria resistance mutations can affect competitive fitness, given our multidrug-resistant (MDR) prevalence, we conducted this study to determine the impact of MDR on the competitive fitness of Mycobacterium tuberculosis (MTB) complex MDR strains. We conducted a cross-sectional study at the University Clinical Research Center (UCRC) from January to December 2017. New TB patients over aged of 18 were recruited at University teaching hospital and health reference centers of Bamako in USTTB Ethical committee approved protocols. Methods: MDR and drug-susceptible (wild-type [WT]) MTB strains (T1 and Beijing) and MTB H37Rv were competed on solid media in UCRC's Tuberculosis Laboratory. Competitive and individual cultures were incubated for 14 days at 37°C with 7% CO2. Number of generation, generation time, and relative competitive fitness (W) of the strains were calculated. Data were analyzed with Epi-Info 7.1.5.2 software (CDC). P value was considered significant when it was <0.05. Scientific calculator (CS-82TL) was used for competitive fitness parameters calculations. Results: We performed 24 competitive cultures and 10 individual cultures. In individual cultures, strains' generation number was for Beijing (WT: 4.60 and mutant MR: 4.40), T1 (WT: 2.69 and MR: 2.37), and H37Rv: 2.91. Generation number of WT strains was less than those of MDR strains in both individual and competitive culture. Relative competitive fitness was below 1 (W<1) in 83.3%. Conclusion: MDR strains were less competitive than WT strains in 83.3% of cases. Resistant mutation impacts bacteria fitness.


Assuntos
Antituberculosos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Aptidão Genética , Mutação , Mycobacterium tuberculosis/genética , Genótipo , Humanos , Mali , Mycobacterium tuberculosis/efeitos dos fármacos , Estudos Prospectivos , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
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