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1.
Ann Palliat Med ; 9(2): 375-387, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32233632

RESUMO

BACKGROUND: This study aimed to develop and evaluate a sustained drug delivery system for the treatment of osteoarticular tuberculosis (TB) to address the issues surrounding low drug concentration in lesions and bone defects or nonunion after debridement. METHODS: The effects of rifapentine on the proliferation and cell cycle of bone marrow mesenchymal stem cells (BMSCs) were evaluated by Cell Counting Kit-8 (CCK-8) and flow cytometry. Rifapentine polylactic acid (PLA) sustained-release microspheres (RPSMs) were prepared through the double emulsion solvent evaporation method and investigated the antibacterial activity in vitro. In this study, two sustained drug delivery systems were prepared by integrating RPSMs and BMSCs into hydroxyapatite/ß-tricalcium phosphate (HA/ß-TCP) or allogeneic bone. We evaluated these drug delivery systems for dynamics of drug release and osteogenic ability by in vitro release test, alkaline phosphatase (ALP) and alizarin red staining, and real-time PCR. RESULTS: The results showed that rifapentine concentrations up to 45.0 µg/mL had no effect on cell proliferation and cell cycle. The encapsulation and drug loading efficiency of the fabricated RPSMs were 78.11%±1.16% and 35.57%±0.85%, respectively. The RPSMs had uniform particle size distribution and a long-term anti-bacterium effect. The HA/ß-TCP-implanted drug delivery system was found to be more effective in reducing the burst release and having a longer duration of sustained release and retention compared to allogeneic bone. The ALP and alizarin red staining and real-time PCR results showed that it had excellent osteoconductive and osteoinductive properties. CONCLUSIONS: In conclusion, the sustained drug delivery system with HA/ß-TCP as scaffold material represents a potential new strategy for TB infections and bone defects.


Assuntos
Antituberculosos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Rifampina/análogos & derivados , Tuberculose Osteoarticular/tratamento farmacológico , Animais , Diferenciação Celular , Proliferação de Células , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Citometria de Fluxo , Osteogênese/efeitos dos fármacos , Coelhos , Rifampina/farmacologia
3.
BMC Infect Dis ; 20(1): 153, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32070292

RESUMO

BACKGROUND: Xpert MTB/RIF (Xpert) is an automated molecular test recommended by World Health Organization (WHO) for diagnosis of tuberculosis (TB). This study evaluated the effect of Xpert implementation on the detection of pulmonary TB (PTB) and rifampicin-resistant TB (RR-TB) cases in Shanghai, China. METHODS: Xpert was routinely implemented in 2018 for all presumptive PTB patients. All PTB patients above 15 years-old identified within the Provincial TB Control Program during the first half of each of 2017 and 2018, were enrolled to compare the difference in proportions of bacteriological confirmation, patients with drug susceptibility test (DST) results for rifampicin (ie, DST coverage) and RR-TB detection before and after Xpert's implementation. RESULTS: A total of 6047 PTB patients were included in the analysis with 1691 tested by Xpert in 2018. Percentages of bacteriological confirmation, DST coverage and RR-TB detection in 2017 and 2018 were 50% vs. 59%, 36% vs. 49% and 2% vs. 3%, respectively (all p-values < 0.05). Among 1103 PTB patients who completed sputum smear, culture and Xpert testing in 2018, Xpert detected an additional 121 (11%) PTB patients who were negative by smear and culture, but missed 248 (23%) smear and/or culture positive patients. Besides, it accounted for an increase of 9% in DST coverage and 1% in RR-TB detection. The median time from first visit to a TB hospital to RR-TB detection was 62 days (interquartile range -IQR 48-84.2) in 2017 vs. 9 days (IQR 2-45.7) in 2018 (p-value < 0.001). In the multivariate model, using Xpert was associated with decreased time to RR-TB detection (adjusted hazard ratio = 4.62, 95% confidence interval: 3.18-6.71). CONCLUSIONS: Integrating Xpert with smear, culture and culture-based DST in a routine setting significantly increased bacteriological confirmation, DST coverage and RR-TB detection with a dramatic reduction in the time to RR-TB diagnosis in Shanghai, China. Our findings can be useful for other regions that attempt to integrate Xpert into routine PTB and RR-TB case-finding cascade. Further study should focus on the identification and elimination of operational level challenges to fully utilize the benefit of rapid diagnosis by Xpert.


Assuntos
Antituberculosos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Rifampina/farmacologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/microbiologia , Adulto , Técnicas Bacteriológicas , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/isolamento & purificação , Sensibilidade e Especificidade , Escarro/microbiologia , Tuberculose Pulmonar/epidemiologia
4.
PLoS Negl Trop Dis ; 14(1): e0007957, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31986143

RESUMO

The elimination of filarial diseases such as onchocerciasis and lymphatic filariasis is hampered by the lack of a macrofilaricidal-adult worm killing-drug. In the present study, we tested the in vivo efficacy of AN11251, a boron-pleuromutilin that targets endosymbiotic Wolbachia bacteria from filarial nematodes and compared its efficacy to doxycycline and rifampicin. Doxycycline and rifampicin were previously shown to deplete Wolbachia endosymbionts leading to a permanent sterilization of the female adult filariae and adult worm death in human clinical studies. Twice-daily oral treatment of Litomosoides sigmodontis-infected mice with 200 mg/kg AN11251 for 10 days achieved a Wolbachia depletion > 99.9% in the adult worms, exceeding the Wolbachia reduction by 10-day treatments with bioequivalent human doses of doxycycline and a similar reduction as high-dose rifampicin (35 mg/kg). Wolbachia reductions of > 99% were also accomplished by 14 days of oral AN11251 at a lower twice-daily dose (50 mg/kg) or once-per-day 200 mg/kg AN11251 treatments. The combinations tested of AN11251 with doxycycline had no clear beneficial impact on Wolbachia depletion, achieving a > 97% Wolbachia reduction with 7 days of treatment. These results indicate that AN11251 is superior to doxycycline and comparable to high-dose rifampicin in the L. sigmodontis mouse model, allowing treatment regimens as short as 10-14 days. Therefore, AN11251 represents a promising pre-clinical candidate that was identified in the L. sigmodontis model, and could be further evaluated and developed as potential clinical candidate for human lymphatic filariasis and onchocerciasis.


Assuntos
Antibacterianos/farmacologia , Diterpenos/farmacologia , Filariose/tratamento farmacológico , Filarioidea/efeitos dos fármacos , Compostos Policíclicos/farmacologia , Wolbachia/efeitos dos fármacos , Animais , Boro , Doxiciclina/farmacologia , Feminino , Filariose/microbiologia , Filarioidea/microbiologia , Camundongos Endogâmicos BALB C , Rifampina/farmacologia , Simbiose
5.
Science ; 367(6474): 200-204, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31919223

RESUMO

Drug combinations are widely used in clinical practice to prevent the evolution of resistance. However, little is known about the effect of tolerance, a different mode of survival, on the efficacy of drug combinations for preventing the evolution of resistance. In this work, we monitored Staphylococcus aureus strains evolving in patients under treatment. We detected the rapid emergence of tolerance mutations, followed by the emergence of resistance, despite the combination treatment. Evolution experiments on the clinical strains in vitro revealed a new way by which tolerance promotes the evolution of resistance under combination treatments. Further experiments under different antibiotic classes reveal the generality of the effect. We conclude that tolerance is an important factor to consider in designing combination treatments that prevent the evolution of resistance.


Assuntos
Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Evolução Molecular , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/microbiologia , Antibacterianos/uso terapêutico , RNA Polimerases Dirigidas por DNA/genética , Daptomicina/farmacologia , Daptomicina/uso terapêutico , Quimioterapia Combinada , Humanos , Testes de Sensibilidade Microbiana , Mutação , Polimorfismo de Nucleotídeo Único , Rifampina/farmacologia , Rifampina/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/farmacologia , Vancomicina/uso terapêutico
6.
Proc Natl Acad Sci U S A ; 117(6): 3185-3191, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-31992637

RESUMO

A fundamental feature of life is that ribosomes read the genetic code in messenger RNA (mRNA) as triplets of nucleotides in a single reading frame. Mutations that shift the reading frame generally cause gene inactivation and in essential genes cause loss of viability. Here we report and characterize a +1-nt frameshift mutation, centrally located in rpoB, an essential gene encoding the beta-subunit of RNA polymerase. Mutant Escherichia coli carrying this mutation are viable and highly resistant to rifampicin. Genetic and proteomic experiments reveal a very high rate (5%) of spontaneous frameshift suppression occurring on a heptanucleotide sequence downstream of the mutation. Production of active protein is stimulated to 61-71% of wild-type level by a feedback mechanism increasing translation initiation. The phenomenon described here could have broad significance for predictions of phenotype from genotype. Several frameshift mutations have been reported in rpoB in rifampicin-resistant clinical isolates of Mycobacterium tuberculosis (Mtb). These mutations have never been experimentally validated, and no mechanisms of action have been proposed. This work shows that frameshift mutations in rpoB can be a mutational mechanism generating antibiotic resistance. Our analysis further suggests that genetic elements supporting productive frameshifting could rapidly evolve de novo, even in essential genes.


Assuntos
RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana/genética , Proteínas de Escherichia coli/genética , Mutação da Fase de Leitura/genética , Genes Essenciais/genética , Escherichia coli/efeitos dos fármacos , Evolução Molecular , Rifampina/farmacologia
7.
Chem Biol Interact ; 315: 108889, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31678598

RESUMO

Although rifampicin could have a hepatic toxic effect, it has also been shown that this chemical acts as a cellular protectant against oxidative stress. Therefore, we wondered whether rifampicin has a beneficial effect such as an anti-oxidant in the liver, because the efficacy of some drugs sometimes relates with their toxicity as well as protective effects. The present study aimed to investigate the antioxidant effect of rifampicin against arachidonic acid (AA) plus iron (AA + iron) cotreatment and against acetaminophen (APAP, 500 mg/kg)-induced oxidative stress, in vitro and in vivo, respectively. In vivo, oral administration of rifampicin (100 or 200 mg/kg) attenuated elevation of serum alanine aminotransferase (ALT) and aspartate transaminase (AST), serum liver injury markers, against APAP treatment and, histologically, ameliorated tissue damage. Under in vitro examination, MTT assays were used to assess the cell death inhibitory effect of rifampicin against AA + iron-induced oxidative stress. In addition, DCFH-DA and Rh 123 staining showed that rifampicin treatment reduced reactive oxygen species (ROS) production and mitochondrial membrane damage, which had been induced by AA + iron treatment. Further, we explored whether rifampicin treatment enhanced phosphorylation of AMP-activated protein kinase (AMPK) by activation of liver kinase B1 (LKB1), the upstream kinase of AMPKα. Activated AMPKα induced activation of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1), which are proteins functioning in redox balance. Moreover, we confirmed a reversed cell protective effect of rifampicin under compound C (an AMPK inhibitor) treatment. Overall, our data demonstrate that rifampicin effectively protects the liver against cellular oxidative stress through AMPKα and Nrf2 pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Rifampina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Fígado , Masculino , Camundongos , Camundongos Endogâmicos ICR , Substâncias Protetoras/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo
8.
Int J Infect Dis ; 92: 175-180, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31881274

RESUMO

BACKGROUND: Patients with suspected pulmonary tuberculosis (PTB) are usually placed in respiratory isolation awaiting three sputum smear microscopy results for acid-fast bacilli (3AFB). GeneXpert MTB/RIF (Xpert) on a pooled sample from two sputa may allow for more rapid de-isolation. OBJECTIVES: To compare the sensitivity and negative predictive value (NPV) of Xpert performed on a single pooled sputum sample ('pooled Xpert') to 3AFB, in order to exclude PTB in patients placed in respiratory isolation. METHODS: Hospital inpatients in respiratory isolation for possible PTB were enrolled prospectively. Three expectorated sputum samples were obtained for smear microscopy. Two of the same samples had 0.5 ml removed from each and pooled for pooled Xpert. The diagnostic accuracy of pooled Xpert and 3AFB were assessed and compared to liquid culture at 8 weeks as the reference standard. RESULTS: Of 56 participants, nine (16.1%) were diagnosed with PTB. Compared to liquid culture, pooled Xpert had a sensitivity of 88.9% (95% confidence interval (CI) 57-99%) and NPV of 97.9% (95% CI 89-99%). 3AFB had a sensitivity of 66.7% (95% CI 35-88%) and NPV of 93.5% (95% CI 83-98%). CONCLUSIONS: A single pooled Xpert was non-inferior to 3AFB, with a strong trend towards greater sensitivity and better NPV. These findings support the use of a single pooled Xpert as an effective rapid screening approach for ruling out PTB in low incidence settings. Its value in high incidence settings and optimal combination with smear microscopy and culture warrant further evaluation.


Assuntos
Técnicas de Diagnóstico Molecular , Mycobacterium tuberculosis , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Adulto , Idoso , Antibióticos Antituberculose/farmacologia , Feminino , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Estudos Prospectivos , Rifampina/farmacologia , Sensibilidade e Especificidade
9.
Zhonghua Jie He He Hu Xi Za Zhi ; 42(12): 901-906, 2019 Dec 12.
Artigo em Chinês | MEDLINE | ID: mdl-31826533

RESUMO

Objective: To investigate the clinical characteristics and drug susceptibility test (DST) of patients infected with different nontuberculous mycobacteria (NTM). Methods: The patients with nontuberculous mycobacterial lung disease (NMLD) in Shanghai Pulmonary Hospital from March 2014 to March 2015 were studied retrospectively by analyzing the clinical characteristics, radiological features and DST results. A total of 201 NMLD patients [male 108, age(58±15) yrs] were enrolled into this study including 48 cases of M. Kansasii [male 13, age (52±16) yrs],46 cases of M. Abscess[male 46, age (57±16) yrs], 92 cases of M. Intracellulare [male 43, age (61±13) yrs], and 15 cases of M. Avium [male 6, age (67±10) yrs]. Clinical data were collected when the diagnosis was made and Chi-square test was used to compare the differences among 4 groups of patients. Bonferroni method was used for further pairwise comparisons. Results: There were significant differences among the 4 groups in the age(χ(2)=6.42, P<0.001) and the gender(χ(2)=49.18, P<0.001) of the patients. The history of bronchiectasis in the groups of M. Kansasii, M. Abscess, M. Intracellulare and M. Avium were 2/48, 31/46, 39/92 and 4/15 cases respectively(χ(2)=41.84, P<0.001). For the Gamma-interferon release assays (ELISA) (IGRA), the positive rate of IGRA in the groups of M. Kansasii, M. Abscess, M. Intracellulare and M. Avium were 83%(40/48), 30%(14/46), 23%(21/92) and 33% (5/15) respectively(χ(2)=50.96, P<0.001). The radiological features were significantly different in tree-in-bud(8/48, 35/46, 36/92 and 4/15 cases respectively, χ(2)=36.48, P<0.001), pleural thickness or mild effusion (21/48, 36/46, 69/92 and 7/15 cases, χ(2)=19.54, P<0.001), bronchiectasis (20/48, 39/46, 78/92 and 10/15 cases, P<0.001) and cavities (38/48, 21/46, 63/92 and 10/15 cases, χ(2)=12.38, P<0.001) among the 4 groups(M. Kansasii, M. Abscess, M. Intracellulare and M. Avium). The drug resistance rates of M. Kansasii to rifampin, ethambutanol and ofloxacin were 10%(5/48), 8%(4/48) and 15%(7/48) respectively; the resistance rates of M.Intracellulare to ethambutanol was 45%(41/92), and the resistance rates of M.Abscess were all over 80% to all anti-TB drugs. The results of pairwise comparisons showed that the male proportion(46/48) and IGRAs positive rate(40/48) of patients with M. Kansasii were higher than those of other groups, and the incidence of bronchiectasis(20/48) and pleural changes(21/48) was lower than those of other groups. The female ratio(33/46), history of bronchiectasis (31/46) and tree-in-bud sign of patients(35/46) with M. Abscess were higher than those of other groups. Conclusions: There were differences in the clinical manifestations and imaging features of 4 common NMLD diseases, which were helpful for clinical differentiation. The patients with M. Kansasii infection were mainly male, with a high IGRA positive rate and fewer lesions of bronchiectasis or pleural changes. Most of the patients with M. Abscess were female, with a previous history of bronchiectasis, and with most of the lesions showing tree-in-bud signs. The NTM species had a high rate of resistance to anti-TB drugs except M. Kansasii.


Assuntos
Antibacterianos/farmacologia , Pneumopatias/tratamento farmacológico , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Micobactérias não Tuberculosas/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Farmacorresistência Bacteriana , Etambutol/farmacologia , Feminino , Humanos , Pneumopatias/microbiologia , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/isolamento & purificação , Ofloxacino/farmacologia , Estudos Retrospectivos , Rifampina/farmacologia , Especificidade da Espécie
10.
Int J Nanomedicine ; 14: 9089-9112, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819421

RESUMO

Purpose: Rifampicin, a first-line anti-tuberculosis drug, was loaded into a carbohydrate-based spray-dried nanocomposite with the aim to design a dry powder inhalation formulation. This strategy can enable efficient distribution of rifampicin within the lungs, localizing its action, enhancing its bioavailability and reducing its systemic exposure consequently side effects. Methods: The respirable nanocomposite was developed utilizing spray drying of rifampicin nanosuspension employing a combination of mannitol, maltodextrin and leucine as microparticles matrix formers. Detailed physicochemical characterization and in-vitro inhalation properties of the nanocomposite particles were investigated. Compatibility studies were carried out using differential scanning calorimetry and Infrared spectroscopy techniques. Moreover, pulmonary in-vitro cytotoxicity on alveolar basal epithelial cells was performed and evaluated. Results: Nanocomposite-based rifampicin-loaded dry inhalable powder containing maltodextrin, mannitol and leucine at a ratio of 2:1:1 was successfully formulated. Rifampicin loading efficiency into the carbohydrate nanocomposite was in the range of 89.3% to 99.2% w/w with a suitable particle size (3.47-6.80 µm) and unimodal size distribution. Inhalation efficiency of the spray-dried nanosuspension was significantly improved after transforming into an inhalable carbohydrate composite. Specifically, mannitol-based powder had higher respirable fraction (49.91%) relative to the corresponding formulation of maltodextrin. Additionally, IC50 value of rifampicin nanocomposite was statistically significantly higher than that of free drug thus providing superior safety profile on lung tissues. Conclusion: The obtained results suggested that spray drying of rifampicin nanosuspension utilizing carbohydrates as matrix formers can enhance drug inhalation performance and reduce cellular toxicity. Thus, representing an effective safer pulmonary delivery of anti-tuberculosis drugs.


Assuntos
Carboidratos/química , Sistemas de Liberação de Medicamentos , Pulmão/efeitos dos fármacos , Nanocompostos/química , Rifampina/farmacologia , Células A549 , Administração por Inalação , Aerossóis , Varredura Diferencial de Calorimetria , Morte Celular , Sobrevivência Celular/efeitos dos fármacos , Inaladores de Pó Seco , Excipientes , Humanos , Manitol/química , Nanocompostos/ultraestrutura , Tamanho da Partícula , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Difração de Raios X
11.
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
12.
Pak J Pharm Sci ; 32(4): 1709-1714, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31608894

RESUMO

Resistance pattern both in newly and previously treated-TB patients and risk factors associated in spread of tuberculosis are investigated in the current study. A total 244 Mycobacterium tuberculosis isolates were used for drug-susceptibility test against four drugs. Environmental risk factors were assessed by using self-designed history proforma. Among 244 TB-isolates, 64% were categorized as MDR-TB in drug-susceptibility test. Male proportion was 51% while 32% belonged to 15-34 years age group and 49% were from city Lahore whereas majority of people (31%) was working on daily wages. Divergent drug-resistance pattern was obtained; RIF (68%), SM (52%), EMB (51%). INH showed only (27%) resistance against first-line anti-TB drug. Drug-resistance prevalence for two drug combination was highest (50%) for (INH+SM) and (INH+EMB) followed by (RIF+SM) (49%) whereas for three drugs combination (INH+RIF+EMB) and (INH+RIF+SM) the prevalence was almost same 50% and 49% respectively while 66% patients were categorized as previously treated and 34% as new TB cases. In drug susceptibility test, 71% were identified as MDR-TB among New TB cases, while 63% were identified as MDR-TB from previously treated cases. Surprisingly DST results displayed that percentage prevalence of MDR-TB both in newly and previously treated cases was almost same.


Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/microbiologia , Adolescente , Adulto , Idoso , Antituberculosos/uso terapêutico , Meio Ambiente , Feminino , Humanos , Isoniazida/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/isolamento & purificação , Paquistão/epidemiologia , Prevalência , Rifampina/farmacologia , Fatores de Risco , Tuberculose/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adulto Jovem
13.
BMC Infect Dis ; 19(1): 851, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31615439

RESUMO

BACKGROUND: In Lao People's Democratic Republic (PDR), tuberculosis (TB) prevalence was estimated at 540/100,000 in 2011. Nevertheless, little is known about the genetic characteristics and anti-TB drug resistance of the Mycobacterium tuberculosis population. The main objective of this work was to study the genetic characteristics and drug resistance of M. tuberculosis population collected during the first National TB Prevalence Survey (TBPS) of Lao PDR (2010-2011). METHODS: Two hundred and twenty two isolates collected during TBPS (2010-2011) were analyzed with the GenoType MTBDRplus test for M. tuberculosis identification and drug resistance detection. Then, 206 of the 222 isolates were characterized by spoligotyping and MIRU-VNTR typing. RESULTS: Among the 222 M. tuberculosis isolates, 11 were mono-resistant to isoniazid and 2 were resistant to isoniazid and rifampicin (MDR-TB), using the GenoType MTBDRplus test. Among the 202 genetically characterized isolates, the East African-Indian (EAI) family was predominant (76.7%) followed by the Beijing (14.4%) and T (5.5%) families. EAI isolates came from all the country provinces, whereas Beijing isolates were found mainly in the northern and central provinces. A higher proportion of Beijing isolates was observed in people younger than 35 years compared to EAI. Moreover, the percentage of drug resistance was higher among Beijing (17.2%) than EAI (5.2%) isolates, and the two MDR-TB isolates belonged to the Beijing family. Combined analysis of the MIRU-VNTR and spoligotyping results (n = 202 isolates) revealed an estimated clustering rate of 11% and the occurrence of mini-outbreaks of drug-resistant TB caused by Beijing genotypes. CONCLUSIONS: The EAI family, the ancient and endemic family in Asia, is predominant in Lao PDR whereas the prevalence of Beijing, the most harmful M. tuberculosis family for humans, is still low, differently from neighboring countries. However, its association with drug resistance, its presence in young patients and its potential association with recent transmission suggest that the Beijing family could change TB epidemiological pattern in Lao PDR. Therefore, efficient TB control and surveillance systems must be maintained and reinforced to prevent the emergence of highly transmissible and drug-resistant strains in Lao PDR, as observed in neighboring countries.


Assuntos
Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Adolescente , Adulto , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Análise por Conglomerados , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Feminino , Genótipo , Humanos , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Laos/epidemiologia , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/isolamento & purificação , Filogenia , Prevalência , Rifampina/farmacologia , Rifampina/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Adulto Jovem
14.
Genes (Basel) ; 10(10)2019 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-31569378

RESUMO

The selection of a suitable combination of reference genes (RGs) for data normalization is a crucial step for obtaining reliable and reproducible results from transcriptional response analysis using a reverse transcription-quantitative polymerase chain reaction. This is especially so if a three-dimensional multicellular model prepared from liver tissues originating from biologically diverse human individuals is used. The mRNA and miRNA RGs stability were studied in thirty-five human liver tissue samples and twelve precision-cut human liver slices (PCLS) treated for 24 h with dimethyl sulfoxide (controls) and PCLS treated with ß-naphthoflavone (10 µM) or rifampicin (10 µM) as cytochrome P450 (CYP) inducers. Validation of RGs was performed by an expression analysis of CYP3A4 and CYP1A2 on rifampicin and ß-naphthoflavone induction, respectively. Regarding mRNA, the best combination of RGs for the controls was YWHAZ and B2M, while YWHAZ and ACTB were selected for the liver samples and treated PCLS. Stability of all candidate miRNA RGs was comparable or better than that of generally used short non-coding RNA U6. The best combination for the control PCLS was miR-16-5p and miR-152-3p, in contrast to the miR-16-5b and miR-23b-3p selected for the treated PCLS. Our results showed that the candidate RGs were rather stable, especially for miRNA in human PCLS.


Assuntos
Perfilação da Expressão Gênica/normas , Fígado/metabolismo , MicroRNAs/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real/normas , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Adulto , Idoso , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/farmacologia , Dimetil Sulfóxido/farmacologia , Feminino , Humanos , Fígado/efeitos dos fármacos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Padrões de Referência , Rifampina/farmacologia , Transcriptoma , Microglobulina beta-2/genética , Microglobulina beta-2/metabolismo , beta-Naftoflavona/farmacologia
16.
Exp Parasitol ; 206: 107769, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31580876

RESUMO

BACKGROUND: Mansonellosis arises from infections with threadlike filarial nematodes in millions of individuals, especially in sub-Saharan Africa. Since infections present no overt clinical symptoms but attenuate immune responses that might lead to increased susceptibility and worsened disease course of concomitant infections, it is truly a neglected tropical disease. Nevertheless, only few studies focus on identifying suitable safe drugs for its control and little is known about the requirements for in vitro maintenance of the Mansonella perstans transmission stage. This study, therefore, evaluated the survival of M. perstans microfilariae (mf) using in vitro conditions that have been shown to promote survival of Loa loa, a closely related filarial nematode. Furthermore, the in vitro microfilaricidal effect of 15 agents was assessed on this helminth. METHODS: The ability of two basic culture media; Dulbecco's Modified Eagle's Medium (DMEM) and Roswell Park Memorial Institute (RPMI-1640) supplemented with 10% fetal bovine serum (FBS) and a monkey kidney epithelial cell line (LLC-MK2) to support the survival of M. perstans microfilariae was investigated. Subsequently, 6 anti-helminthics, 5 anti-malarials, 1 anti-microbacterial, 2 trypanocidals and 1 anti-cancer agent were tested in vitro against mf. The suitability of the culture media as well as the effect of the anti-infective agents on mf survival was assessed by scoring their motility. RESULTS: FBS supplement and additional LLC-MK2 cells significantly improved the survival of mf in DMEM and RPMI-1640 culture. In detail, RPMI-1640 supplemented with 10% FBS and LLC-MK2 cells sustained the maintenance of mf for at least 20 days (100.00 ±â€¯0.00% survival). In co-cultures with LLC-MK2 cells without serum, M. perstans mf were maintained in DMEM and RPMI-1640 medium with a motility above 99% by day 5. Mefloquine displayed the highest microfilaricidal effect in vitro followed by artesunate. CONCLUSION: Both RPMI and DMEM in the presence of LLC-MK2 cells are suitable for the maintenance of M. perstans mf in vitro. In absence of the feeder cells, the addition of 10% FBS to RPMI-1640 medium improved the parasite survival rate and motility. The microfilaricidal activity of mefloquine and artesunate on M. perstans mf was documented for the first time in this study and can therefore be considered as reference for further screening of agents against this parasite stage.


Assuntos
Artesunato/farmacologia , Filaricidas/farmacologia , Mansonella/efeitos dos fármacos , Mansonella/crescimento & desenvolvimento , Mefloquina/farmacologia , Amodiaquina/farmacologia , Animais , Antimaláricos/farmacologia , Antinematódeos/farmacologia , Área Sob a Curva , Bovinos , Linhagem Celular , Meios de Cultura/química , Haplorrinos , Ivermectina/farmacologia , Mansonella/fisiologia , Microfilárias/efeitos dos fármacos , Microfilárias/crescimento & desenvolvimento , Microfilárias/fisiologia , Movimento/efeitos dos fármacos , Rifampina/farmacologia
17.
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
18.
PLoS Biol ; 17(10): e3000515, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31652256

RESUMO

Evolved resistance to one antibiotic may be associated with "collateral" sensitivity to other drugs. Here, we provide an extensive quantitative characterization of collateral effects in Enterococcus faecalis, a gram-positive opportunistic pathogen. By combining parallel experimental evolution with high-throughput dose-response measurements, we measure phenotypic profiles of collateral sensitivity and resistance for a total of 900 mutant-drug combinations. We find that collateral effects are pervasive but difficult to predict because independent populations selected by the same drug can exhibit qualitatively different profiles of collateral sensitivity as well as markedly different fitness costs. Using whole-genome sequencing of evolved populations, we identified mutations in a number of known resistance determinants, including mutations in several genes previously linked with collateral sensitivity in other species. Although phenotypic drug sensitivity profiles show significant diversity, they cluster into statistically similar groups characterized by selecting drugs with similar mechanisms. To exploit the statistical structure in these resistance profiles, we develop a simple mathematical model based on a stochastic control process and use it to design optimal drug policies that assign a unique drug to every possible resistance profile. Stochastic simulations reveal that these optimal drug policies outperform intuitive cycling protocols by maintaining long-term sensitivity at the expense of short-term periods of high resistance. The approach reveals a new conceptual strategy for mitigating resistance by balancing short-term inhibition of pathogen growth with infrequent use of drugs intended to steer pathogen populations to a more vulnerable future state. Experiments in laboratory populations confirm that model-inspired sequences of four drugs reduce growth and slow adaptation relative to naive protocols involving the drugs alone, in pairwise cycles, or in a four-drug uniform cycle.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Enterococcus faecalis/efeitos dos fármacos , Genoma Bacteriano , Modelos Estatísticos , Ampicilina/farmacologia , Evolução Molecular Direcionada , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Sinergismo Farmacológico , Enterococcus faecalis/genética , Enterococcus faecalis/crescimento & desenvolvimento , Enterococcus faecalis/metabolismo , Fosfomicina/farmacologia , Aptidão Genética , Testes de Sensibilidade Microbiana , Mutação , Rifampina/farmacologia , Seleção Genética , Processos Estocásticos , Tigeciclina/farmacologia , Sequenciamento Completo do Genoma
19.
BMC Infect Dis ; 19(1): 823, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533647

RESUMO

BACKGROUND: The purpose of this study was to gather temporal trends on bacteria epidemiology and resistance of intraoperative bone culture from chronic ostemyelitis at an affiliated hospital in South China. METHOD: Records of patients with chronic osteomyelitis from 2003 to 2014 were retrospectively reviewed. The medical data were extracted using a unified protocol. Antimicrobial susceptibility testing was carried out by means of a unified protocol using the Kirby-Bauer method, results were analyzed according to Clinical and Laboratory Standards Institute definitions. RESULT: Four hundred eighteen cases met our inclusion criteria. For pathogen distribution, the top five strains were Staphylococcus aureus (27.9%); Pseudomonas aeruginosa (12.1%); Enterobacter cloacae (9.5%); Acinetobacter baumanii (9.0%) and Escherichia coli (7.8%). Bacterial culture positive rate was decreased significantly among different year-groups. Mutiple bacterial infection rate was 28.1%. One strain of Staphylococcus aureus was resistant to linezolid and vancomycin. Resistance of Pseudomonas aeruginosa stains to Cefazolin, Cefuroxime, Cefotaxime, and Cefoxitin were 100% nearly. Resistance of Acinetobacter baumanii stains against Cefazolin, Cefuroxime were 100%. Ciprofloxacin resistance among Escherichia coli isolates increased from 25 to 44.4%. On the contrary, resistance of Enterobacter cloacae stains to Cefotaxime and Ceftazidime were decreased from 83.3 to 36.4%. CONCLUSIONS: From 2003 to 2014, positive rate of intraoperative bone culture of chronic osteomyelitis was decreased; the proportion of Staphylococcus aureus was decreased gradually, and our results indicate the importance of bacterial surveilance studies about chronic osteomyelitis.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Osteomielite/diagnóstico , Adolescente , Adulto , Antibacterianos/uso terapêutico , Cefotaxima/farmacologia , Cefotaxima/uso terapêutico , China , Doença Crônica , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Feminino , Hospitais , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Osteomielite/tratamento farmacológico , Osteomielite/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Estudos Retrospectivos , Rifampina/farmacologia , Rifampina/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Adulto Jovem
20.
Pan Afr Med J ; 33: 111, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31489089

RESUMO

Introduction: High mortality among individuals receiving retreatment for tuberculosis (RT-TB) persists, although reasons for these poor outcomes remain unclear. Methods: We retrospectively reviewed 394 RT-TB patients diagnosed between January 2010 and June 2016 in Accra, Ghana. Results: Of RT-TB patients, 161 (40.9%) were treated empirically (negative/absent smear, culture or Xpert), of whom 30.4% (49/161) had only extrapulmonary TB signs or symptoms. Mortality during treatment was 19.4%; 15-day mortality was 10.8%. In multivariable proportional hazards regression, living with HIV (aHR=2.69 [95 CI: 1.51, 4.80], p<0.01) and previous loss-to-follow up (aHR=8.27 (95 CI: 1.10, 62.25), p=0.04) were associated with mortality, while drug susceptibility testing (DST, aHR=0.36 (95 CI: 0.13, 1.01), p=0.052) was protective. Isoniazid resistance was observed in 40% (23/58 tested) and rifampin resistance in 19.1% (12/63 tested). Conclusion: High rates of extrapulmonary TB and smear/culture negative disease highlight the barriers to achieving DST-driven RT-TB regimens and the need for improved diagnostics. Our finding of poly-drug resistance in rifampin-susceptible cases supports access to comprehensive first line DST. Additionally, interventions to reduce mortality, especially in HIV co-infected RT-TB patients, are urgently needed.


Assuntos
Antituberculosos/administração & dosagem , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose/tratamento farmacológico , Adulto , Antituberculosos/farmacologia , Estudos de Coortes , Farmacorresistência Bacteriana Múltipla , Feminino , Gana , Infecções por HIV/epidemiologia , Humanos , Isoniazida/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Retratamento , Estudos Retrospectivos , Rifampina/farmacologia , Tuberculose/microbiologia , Tuberculose/mortalidade , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/mortalidade
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