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1.
Int J Mol Sci ; 24(12)2023 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-37373451

RESUMO

This study aimed to determine phenotypic and genotypic drug resistance patterns of Mycobacterium tuberculosis strains from children with tuberculosis (TB) in China and Russia, two high-burden countries for multi/extensively-drug resistant (MDR/XDR) TB. Whole-genome sequencing data of M. tuberculosis isolates from China (n = 137) and Russia (n = 60) were analyzed for phylogenetic markers and drug-resistance mutations, followed by comparison with phenotypic susceptibility data. The Beijing genotype was detected in 126 Chinese and 50 Russian isolates. The Euro-American lineage was detected in 10 Russian and 11 Chinese isolates. In the Russian collection, the Beijing genotype and Beijing B0/W148-cluster were dominated by MDR strains (68% and 94%, respectively). Ninety percent of B0/W148 strains were phenotypically pre-XDR. In the Chinese collection, neither of the Beijing sublineages was associated with MDR/pre-XDR status. MDR was mostly caused by low fitness cost mutations (rpoB S450L, katG S315T, rpsL K43R). Chinese rifampicin-resistant strains demonstrated a higher diversity of resistance mutations than Russian isolates (p = 0.003). The rifampicin and isoniazid resistance compensatory mutations were detected in some MDR strains, but they were not widespread. The molecular mechanisms of M. tuberculosis adaptation to anti-TB treatment are not unique to the pediatric strains, but they reflect the general situation with TB in Russia and China.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Humanos , Criança , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Rifampina , Filogenia , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Mycobacterium tuberculosis/genética , Federação Russa/epidemiologia , Mutação , Genótipo , China/epidemiologia , Resistência a Medicamentos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/genética , Farmacorresistência Bacteriana Múltipla/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-32513801

RESUMO

Data of developmental pharmacokinetics (PK) of meropenem in critically ill infants and children with severe infections are limited. We assessed the population PK and defined the appropriate regimen to optimize treatment in this population based on developmental PK-pharmacodynamic (PD) analysis. Blood samples were collected from pediatric intensive care unit patients with severe infection treated with standard dosage regimens for meropenem. Population PK data were analyzed using NONMEM software. Fifty-seven patients (mean age, 2.96 years [range, 0.101 to 14.4]; mean body weight, 15.8 kg [range, 5.0 to 65.0]) were included. A total of 135 meropenem concentrations were obtainable for population PK modeling. The median number of samples per patients was 2 (range, 1 to 4). A two-compartment model with first-order elimination was optimal for PK modeling. Weight and creatinine clearance (estimated by the Schwartz formula) were significantly correlated with the PK parameters of meropenem. The probabilities of target attainment for pathogens with low MICs of 1 and 2 µg/ml were 87.5% and 68.6% following administration of 40 mg/kg/dose (every 8 h [q8h]) as a 4-h infusion and 98.0% and 73.3% with high MICs of 4 and 8 µg/ml following administration of 110 mg/kg/day as a continuous infusion in critically ill infants and children under 70% fT>MIC (the free time during which the plasma concentration of meropenem exceeds the MIC), respectively. The standard dosage regimens for meropenem did not meet an appropriate PD target, and an optimal dosing regimen was established in critically ill infants and children. (This study has been registered at ClinicalTrials.gov under identifier NCT03643497.).


Assuntos
Antibacterianos , Estado Terminal , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Humanos , Lactente , Meropeném , Testes de Sensibilidade Microbiana , Tienamicinas
3.
J Antimicrob Chemother ; 75(7): 1917-1924, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32129861

RESUMO

OBJECTIVES: To evaluate the population pharmacokinetics of cefoperazone in children and establish an evidence-based dosing regimen using a developmental pharmacokinetic-pharmacodynamic approach in order to optimize cefoperazone treatment. METHODS: A model-based, open-label, opportunistic-sampling pharmacokinetic study was conducted in China. Blood samples from 99 cefoperazone-treated children were collected and quantified by HPLC/MS. NONMEM software was used for population pharmacokinetic-pharmacodynamic analysis. This study was registered at ClinicalTrials.gov (NCT03113344). RESULTS: A two-compartment model with first-order elimination agreed well with the experimental data. Covariate analysis showed that current body weight had a significant effect on the pharmacokinetics of cefoperazone. Monte Carlo simulation showed that for bacteria for which cefoperazone has an MIC of 0.5 mg/L, 78.1% of hypothetical children treated with '40 mg/kg/day, q8h, IV drip 3 h' would reach the pharmacodynamic target. For bacteria for which cefoperazone has an MIC of 8 mg/L, 88.4% of hypothetical children treated with 80 mg/kg/day (continuous infusion) would reach the treatment goal. A 160 mg/kg/day (continuous infusion) regimen can cover bacteria for which cefoperazone has an MIC of 16 mg/L. Nevertheless, even if using the maximum reported dose of 160 mg/kg/day (continuous infusion), the ratio of hypothetical children reaching the treatment target was only 9.9% for bacteria for which cefoperazone has an MIC of 32 mg/L. CONCLUSIONS: For cefoperazone, population pharmacokinetics were evaluated in children and an appropriate dosing regimen was developed based on developmental pharmacokinetics-pharmacodynamics. The dose indicated in the instructions (20-160 mg/kg/day) can basically cover the clinically common bacteria for which cefoperazone has an MIC of ≤16 mg/L. However, for bacteria for which the MIC is >16 mg/L, cefoperazone is not a preferred choice.


Assuntos
Antibacterianos , Cefoperazona , Antibacterianos/uso terapêutico , Criança , China , Cromatografia Líquida de Alta Pressão , Humanos , Testes de Sensibilidade Microbiana , Método de Monte Carlo
4.
Eur J Clin Pharmacol ; 76(11): 1547-1556, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32583354

RESUMO

PURPOSE: To assess ceftriaxone population pharmacokinetics in a large pediatric population and describe the proper dose for establishing an optimized antibiotic regimen. METHODS: From pediatric patients using ceftriaxone, blood samples were obtained and the concentration was measured using high-performance liquid chromatography ultraviolet detection. The NONMEM software program was used for population pharmacokinetic analysis, for which data from 99 pediatric patients (2 to 12 years old) was collected and 175 blood concentrations were obtained. RESULTS: The best fit with the data was shown by the one-compartment model with first-order elimination. According to covariate analysis, weight had a significant impact on the clearance of ceftriaxone. Using Monte Carlo simulation, in a pediatric population with community-acquired pneumonia, a dose regimen of 100 mg/kg every 24 h produced satisfactory target attainment rates while remaining within the required minimum inhibitory concentration (2 mg/L). CONCLUSION: Population pharmacokinetics of ceftriaxone was evaluated in children and an optimum dosing regimen was constructed on the basis of the pharmacokinetics-pharmacodynamics model-based approach.


Assuntos
Ceftriaxona/farmacocinética , Infecções Comunitárias Adquiridas/tratamento farmacológico , Pneumonia/tratamento farmacológico , Ceftriaxona/administração & dosagem , Criança , Pré-Escolar , Humanos , Modelos Biológicos , Método de Monte Carlo
5.
Mikrochim Acta ; 187(12): 667, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33211195

RESUMO

A new nucleic acid detection technique, termed Nano-SAMRS-RPA, is reported which employed carbon nanomaterial (graphene oxide, GO) and self-avoiding molecular recognition systems (SAMRS) to improve the specificity of recombinase polymerase amplification (RPA). In the presence of GO and SAMRS primers, the assay artifacts, including primer-dimers, nonspecific products, off-target hybrids, and non-canonical folds, are completely suppressed and eliminated, which makes the creation of RPA-based methods faster by simplifying the primer design and eliminating the need for primer optimization and complex probe. Moreover, a lateral flow bioassay (LFB) was also devised for simply and rapidly indicating the Nano-SAMRS-RPA results. Particularly, the new detection system only requires a single-labeled primer, eliminating the false-positive result from hybridization (the labeled probe and reverse primer) and the use of real-time instrument, more complex enzymatic solutions, and probes. As a result, GO, SAMRS primers, and LFB convert RPA from a technique suited only for the research laboratory into one that has a practical value in clinical settings, field environments, and at points-of-care testing. Human papillomaviruses (HPV) genotypes 16 and 18 were applied as model analytes to test the assay's availability. The initial data indicated that Nano-SAMRS-RPA could detect down to 10 copies per reaction, and the sensitivity (14/14 samples collected from HPV16 and HPV 18 patients) and specificity (75/75 samples collected from non-HPV patients) for clinical sample detection were 100%. The proof-of-concept technique can be reconfigured to detect various nucleic acid sequences by redesigning the specific RPA primers.Graphical abstract.


Assuntos
Grafite/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Ácidos Nucleicos/análise , DNA Viral/análise , DNA Viral/metabolismo , Genótipo , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Limite de Detecção , Ácidos Nucleicos/metabolismo , Recombinases/metabolismo , Reprodutibilidade dos Testes
6.
Hum Mol Genet ; 26(23): 4752-4763, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036319

RESUMO

Genome-wide association studies (GWASs) have revealed the worldwide heterogeneity of genetic factors in tuberculosis (TB) susceptibility. Despite having the third highest global TB burden, no TB-related GWAS has been performed in China. Here, we performed the first three-stage GWAS on TB in the Han Chinese population. In the stage 1 (discovery stage), after quality control, 691 388 SNPs present in 972 TB patients and 1537 controls were retained. After replication on an additional 3460 TB patients and 4862 controls (stages 2 and 3), we identified three significant loci associated with TB, the most significant of which was rs4240897 (logistic regression P = 1.41 × 10-11, odds ratio = 0.79). The aforementioned three SNPs were harbored by MFN2, RGS12 and human leukocyte antigen class II beta chain paralogue encoding genes, all of which are candidate immune genes associated with TB. Our findings provide new insight into the genetic background of TB in the Han Chinese population.


Assuntos
GTP Fosfo-Hidrolases/genética , Proteínas Mitocondriais/genética , Proteínas RGS/genética , Tuberculose/genética , Adulto , Alelos , Povo Asiático/genética , Estudos de Casos e Controles , China , Etnicidade/genética , Feminino , GTP Fosfo-Hidrolases/metabolismo , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Mitocondriais/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Proteínas RGS/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-30509939

RESUMO

Amoxicillin is widely used to treat bacterial infections in neonates. However, considerable intercenter variability in dosage regimens of antibiotics exists in clinical practice. The pharmacokinetics of amoxicillin has been described in only a few preterm neonates. Thus, we aimed to evaluate the population pharmacokinetics of amoxicillin through a large sample size covering the entire age range of neonates and young infants and to establish evidence-based dosage regimens based on developmental pharmacokinetics-pharmacodynamics. This is a prospective, multicenter, pharmacokinetic study using an opportunistic sampling design. Amoxicillin plasma concentrations were determined using high-performance liquid chromatography. Population pharmacokinetic analysis was performed using NONMEM. A total of 224 pharmacokinetic samples from 187 newborns (postmenstrual age range, 28.4 to 46.3 weeks) were available for analysis. A two-compartment model with first-order elimination was used to describe population pharmacokinetics. Covariate analysis showed that current weight, postnatal age, and gestational age were significant covariates. The final model was further validated for predictive performance in an independent cohort of patients. Monte Carlo simulation demonstrated that for early-onset sepsis, the currently used dosage regimen (25 mg/kg twice daily [BID]) resulted in 99.0% of premature neonates and 87.3% of term neonates achieving the pharmacodynamic target (percent time above MIC), using a MIC breakpoint of 1 mg/liter. For late-onset sepsis, 86.1% of premature neonates treated with 25 mg/kg three times a day (TID) and 79.0% of term neonates receiving 25 mg/kg four times a day (QID) reached the pharmacodynamic target, using a MIC breakpoint of 2 mg/liter. The population pharmacokinetics of amoxicillin was assessed in neonates and young infants. A dosage regimen was established based on developmental pharmacokinetics-pharmacodynamics.


Assuntos
Amoxicilina/administração & dosagem , Amoxicilina/farmacocinética , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Modelos Teóricos , Estudos Prospectivos
8.
Artigo em Inglês | MEDLINE | ID: mdl-29941652

RESUMO

Azithromycin is extensively used in children with community-acquired pneumonia (CAP). Currently, the intravenous azithromycin is used off-label in children partly due to lacking of pharmacokinetic data. Our objective was to evaluate the population pharmacokinetics (PPK) and optimize dose strategy in order to improve treatment in this distinctive population. This was a prospective, multicenter, open-labeled pharmacokinetic study. Blood samples were collected from hospitalized pediatric patients and concentrations were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). PPK analysis was conducted using NONMEM software. The pharmacokinetic data from 95 pediatric patients (age range, 2.1 to 11.7 years) were available for analysis. The PPK was best fitted by a two-compartment model with linear elimination. Covariate analysis verified that body weight and alanine aminotransferase (ALT) had significant effects on azithromycin pharmacokinetics, yielding a 24% decrease of clearance in patients with ALT of >40. Monte Carlo simulation showed that for children with normal liver function, a loading-dose strategy (a loading dose of 15 mg/kg of body weight followed by maintenance doses of 10 mg/kg) would achieve the ratio of the area under free drug plasma concentration-time curve over 24 h (fAUC) to MIC90 (fAUC/MIC) target of 3 h in 53.2% of hypothetical patients, using a normative MIC susceptibility breakpoint of 2 mg/liter. For children with ALT of >40, the proposed dose needed to decrease by 15% to achieve comparable exposure. The corresponding risk of overdose for the recommended dosing regimen was less than 5.8%. In conclusion, the PPK of azithromycin was evaluated in children with CAP and an optimal dosing regimen was constructed based on developmental pharmacokinetic-pharmacodynamic modeling and simulation.


Assuntos
Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Azitromicina/farmacocinética , Azitromicina/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Pneumonia/tratamento farmacológico , Alanina Transaminase/metabolismo , Criança , Pré-Escolar , Cromatografia Líquida/métodos , Infecções Comunitárias Adquiridas/metabolismo , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana/métodos , Método de Monte Carlo , Pneumonia/metabolismo , Estudos Prospectivos , Espectrometria de Massas em Tandem/métodos
9.
Biomed Chromatogr ; 32(8): e4243, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29573350

RESUMO

Latamoxef, a broad-spectrum anti-bacterial agent of the ß-lactam antibiotics, is used off-label in treatment of neonatal sepsis. Large inter-individual variability and uncertainty of treatment make therapeutic drug monitoring (TDM) useful to optimize antimicrobial therapy. The objective of this study was to develop and validate a simple, selective and reliable HPLC method for the determination of latamoxef in small volumes of plasma, which could be used in neonatal TDM. After a simple protein precipitation, analytes were separated with liquid chromatography and quantified by UV detection, with tinidazole as the internal standard. The calibration range was linear from 3.0 to 60.0 µg/mL. Intra- and inter-day precisions were < 7.2%. The acceptance criteria of accuracy (between 85 and 115%, 120% for lower limit of quantification) were met in all cases. A plasma volume of 50 µL was required to achieve the limit of quantification of 3.0 µg/mL. The TDM results showed a large variability in trough concentrations. A large number of patients were underdosed, highlighting the unmet need for TDM to optimize latamoxef therapy in neonates.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Monitoramento de Medicamentos/métodos , Moxalactam/sangue , Moxalactam/farmacocinética , Estabilidade de Medicamentos , Humanos , Recém-Nascido , Modelos Lineares , Moxalactam/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
10.
J Proteome Res ; 15(9): 3118-25, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27451809

RESUMO

Although tuberculosis (TB) has been the greatest killer due to a single infectious disease, pediatric TB is still hard to diagnose because of the lack of sensitive biomarkers. Metabolomics is increasingly being applied in infectious diseases. But little is known regarding metabolic biomarkers in children with TB. A combination of a NMR-based plasma metabolic method and classification and regression tree (CART) analysis was used to provide a broader range of applications in TB diagnosis in our study. Plasma samples obtained from 28 active TB children and 37 non-TB controls (including 21 RTIs and 16 healthy children) were analyzed by an orthogonal partial least-squares discriminant analysis (OPLS-DA) model, and 17 metabolites were identified that can separate children with TB from non-TB controls. CART analysis was then used to choose 3 of the markers, l-valine, pyruvic acid, and betaine, with the least error. The sensitivity, specificity, and area under the curve (AUC) of the 3 metabolites is 85.7% (24/28, 95% CI, 66.4%, 95.3%), 94.6% (35/37, 95% CI, 80.5%, 99.1%), and 0.984(95% CI, 0.917, 1.000), respectively. The 3 metabolites demonstrated sensitivity of 82.4% (14/17, 95% CI, 55.8%, 95.3%) and specificity of 83.9% (26/31, 95% CI, 65.5%, 93.9%), respectively, in 48 blinded subjects in an independent cohort. Taken together, the novel plasma metabolites are potentially useful for diagnosis of pediatric TB and would provide insights into the disease mechanism.


Assuntos
Tuberculose/diagnóstico , Betaína/análise , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Análise Discriminante , Humanos , Espectroscopia de Ressonância Magnética , Metaboloma , Metabolômica/métodos , Plasma/metabolismo , Ácido Pirúvico/análise , Sensibilidade e Especificidade , Valina/análise
11.
Antimicrob Agents Chemother ; 60(5): 2807-12, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26902762

RESUMO

Mycobacterium tuberculosis can acquire resistance to rifampin (RIF) through mutations in the rpoB gene. This is usually accompanied by a fitness cost, which, however, can be mitigated by secondary mutations in the rpoA or rpoC gene. This study aimed to identify rpoA and rpoC mutations in clinical M. tuberculosis isolates in northern China in order to clarify their role in the transmission of drug-resistant tuberculosis (TB). The study collection included 332 RIF-resistant and 178 RIF-susceptible isolates. The majority of isolates belonged to the Beijing genotype (95.3%, 486/510 isolates), and no mutation was found in rpoA or rpoC of the non-Beijing genotype strains. Among the Beijing genotype strains, 27.8% (89/320) of RIF-resistant isolates harbored nonsynonymous mutations in the rpoA (n = 6) or rpoC (n = 83) gene. The proportion of rpoC mutations was significantly higher in new cases (P = 0.023) and in strains with the rpoB S531L mutation (P < 0.001). In addition, multidrug-resistant (MDR) strains with rpoC mutations were significantly associated with 24-locus mycobacterial interspersed repetitive-unit-variable-number tandem-repeat clustering (P = 0.016). In summary, we believe that these findings indirectly suggest an epistatic interaction of particular mutations related to RIF resistance and strain fitness and, consequently, the role of such mutations in the spread of MDR M. tuberculosis strains.


Assuntos
Rifampina/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Proteínas de Bactérias/genética , China , Farmacorresistência Bacteriana Múltipla/genética , Genótipo , Testes de Sensibilidade Microbiana , Mutação/genética , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos/genética
12.
BMC Microbiol ; 16: 85, 2016 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-27176471

RESUMO

BACKGROUND: As the epidemic of MDR-TB and XDR-TB becomes increasingly severe, it is important to determine the clinical characteristics and molecular epidemiology of MDR-TB and XDR-TB. Recently, many studies have shown that clinical features and molecular characteristics of drug-resistant strains vary in different geographical areas, however, further information is needed to assess the dynamic evolution of drug-resistant TB. Comparative studies between different time periods are necessary to elucidate the development of drug-resistant TB. RESULTS: A total of 255 and 537 strains were collected from Beijing Chest Hospital in 2006 and in 2012, respectively. Drug-resistance rates and mutations associated with resistance to first-line anti-tuberculosis (TB) drugs were compared. The overall rate of drug resistance among strains of TB in 2012 was 54.4 %, significantly higher than that in 2006 (34.9 %, P < 0.001). Rates of resistance to each first-line drug (isoniazid, rifampicin, streptomycin and ethambutol) and to second-line drug ofloxacin increased significantly from 2006 to 2012. The overall MDR rate also increased significantly from 2006 (14.9 %) to 2012 (27.0 %). The rate of MDR increased significantly between these two time periods in previously treated cases (P = 0.023) but not in new cases (P = 0.073), and the rate of XDR was similar in new cases at the two time periods, but was marginally higher in 2012 in previously treated cases (P = 0.056). Previous treatment was found to be a risk factor for drug-resistant TB, especially for MDR-TB. In addition, the proportion of drug resistant isolates in which katG, the mabA-inhA promoter, oxyR-ahpC intergenic region, rpoB, rpsL, and embB were mutated was similar in 2006 and 2012, however patterns of mutation in these loci were more diverse in 2012 compared to 2006. CONCLUSIONS: Our data suggests that the prevalence of drug resistant TB remains high in Beijing, China, and that increasing rates of resistance in M. tuberculosis to all anti-TB drugs should be considered when choosing an optimal anti-TB regimen. Moreover, acquired multi-drug resistance may play a primary role in the MDR-TB epidemic in Beijing, China. Consequently, this highlights the importance of an earlier start to effective and supervised treatment in order to reduce the burden of retreatment.


Assuntos
Antituberculosos/farmacologia , Tuberculose Extensivamente Resistente a Medicamentos/epidemiologia , Mycobacterium tuberculosis/classificação , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Proteínas de Bactérias/genética , China , Farmacorresistência Bacteriana Múltipla , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Taxa de Mutação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Prevalência , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
13.
Yi Chuan ; 38(10): 910-917, 2016 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-27806932

RESUMO

The occurance and prevalence of multidrug-resistant tuberculosis poses a serious threat to the global tuberculosis control. Ethambutol (EMB) is one of the first-line anti-tuberculosis drugs, which is usually used in combination with isoniazid and rifampicin for treating pan-sensitive tuberculosis, and it can also be used in drug-resistant tuberculosis. However, the situation of EMB resistance is alarmingly high, especially in multi-drug resistant tuberculosis. In China, EMB resistance rate in the previously treated cases was up to 17.2% and showed an increased tendency. What was worse, 51.3%-66.7% of multidrug-resistant tuberculosis cases were resistant to EMB. Thus, it is important to understand the drug resistance mechanism of EMB, which will help to slow down the drug resistance rate of EMB. In this review, we focus on the current status of EMB resistance, the effects of EMB and the mechanisms of EMB resistance in Mycobacterium tuberculosis.


Assuntos
Antituberculosos/farmacologia , Farmacorresistência Bacteriana , Etambutol/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Tuberculose/tratamento farmacológico
14.
J Clin Microbiol ; 52(5): 1691-3, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24523461

RESUMO

Mycobacterium tuberculosis Beijing genotype strains are rapidly disseminating, frequently hypervirulent, and multidrug resistant. Here, we describe a method for their rapid detection by real-time PCR that targets the specific IS6110 insertion in the dnaA-dnaN genome region. The method was evaluated with a geographically and genetically diverse collection representing areas in East Asia and the former Soviet Union in which the Beijing genotype is endemic and epidemic (i.e., major foci of its global propagation) and with clinical specimens.


Assuntos
Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Tuberculose/diagnóstico , Técnicas de Tipagem Bacteriana/métodos , DNA Bacteriano/genética , Genes Bacterianos/genética , Genótipo , Humanos
15.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(10): 988-92, 2014 Oct.
Artigo em Zh | MEDLINE | ID: mdl-25344177

RESUMO

OBJECTIVE: To investigate nasopharyngeal carriage rate, antimicrobial resistance and serotype distribution of Streptococcus pneumoniae among children with upper respiratory infection. METHODS: Nasopharygeal swabs were collected from children with upper respiratory infection visiting the outpatient department of Beijing Children's Hospital between March 2013 and February 2014. The antibiotic susceptibility was tested by Etest method, and the serotype was determined by Quellung reaction. RESULTS: The nasopharyngeal carriage rate for Streptococcus pneumoniae was 23.8% (699/2 941). One hundred isolates were randomly chosen for antimicrobial susceptiblity test and serotyping. Up to 98.0% isolates were susceptible to parenteral penicillin. The susceptible rate against oral penicillin, however, was 33.0%. The non-susceptible rate to erythromycin and azithromycin was 97.0%. The multi-drug resistance rate was up to 86.0%. The common serotypes were 6A(12.0%), 19F(12.0%), 6B(10.0%), 23F(9.0%) and 14(8.0%). The coverage rates of 7-, 10- and 13-valent pneumococcal conjugate vaccine were 41.0%, 42.0% and 59.0% respectively. CONCLUSIONS: About 25% of children with upper respiratory infection are nasopharyngeal colonized by Streptococcus pneumoniae. The isolates show a high antimicrobial resistance. The 13-valent pneumococcal conjugate vaccine covers about 60.0% of the isolates.


Assuntos
Portador Sadio/epidemiologia , Nasofaringe/microbiologia , Infecções Respiratórias/microbiologia , Streptococcus pneumoniae/isolamento & purificação , Adolescente , Portador Sadio/microbiologia , Criança , Pré-Escolar , Farmacorresistência Bacteriana , Feminino , Humanos , Lactente , Masculino , Vacinas Pneumocócicas/imunologia , Sorotipagem , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/efeitos dos fármacos
17.
Mol Biol Rep ; 40(9): 5477-82, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23737189

RESUMO

Host genetic factors play a major role in determining differential susceptibility to human tuberculosis (TB), a re-emerging infectious disease throughout the world. Genetic variations in the IFNG gene coding for interferon gamma (IFN-γ), have been identified in TB patients. To investigate the association of the IFNG polymorphisms with TB susceptibility in Chinese pediatric population. A case-control study of 189 TB patients and 164 controls was performed using single-nucleotide polymorphism (SNP) analysis. Genomic DNA was extracted from leukocytes in peripheral blood. Three SNPs of IFNG, including -1616C/T (rs2069705), +874A/T (rs2430561), and +3234C/T (rs2069718), were selected for genotyping and analysis. The +874A and +3234C alleles were more frequent among TB patients (P = 0.108 and P = 0.088), especially in females (both P = 0.029), although this difference was not significant since Bonferroni corrected significance threshold was 0.025 (two of three SNPs were found to be in linkage disequilibrium). More pronounced differences for the +874 and +3234 polymorphisms were found under the genotype comparison between TB cases and controls in the total population [P = 0.026 (borderline non-significance) and P = 0.020, respectively], and in the female subgroup (P = 0.020 and P = 0.020). The dominant model of inheritance was shown to be significant for +874A and +3234C alleles (both P = 0.019) in the female subgroup. The +874A and +3234C alleles were more frequently found in extrapulmonary TB patients than in controls (P = 0.039). Haplotype analysis carried out on these three SNPs showed the TTT haplotype to be more frequent in controls than in TB cases, and this difference showed a strong significance (P = 0.005). The +874A and +3234C alleles may be related to TB susceptibility in the female subgroup in the Chinese pediatric population of North China. The higher rate of +874A (known to correlate with lower IFN-γ expression) in the extrapulmonary TB subgroup suggests a sufficient IFN-γ expression to be not only an important factor for the onset of TB disease but also for limiting its dissemination to lungs.


Assuntos
Povo Asiático/genética , Interferon gama/genética , Polimorfismo de Nucleotídeo Único/genética , Tuberculose/genética , Estudos de Casos e Controles , Criança , Primers do DNA/genética , Feminino , Estudos de Associação Genética , Genótipo , Haplótipos/genética , Humanos , Padrões de Herança/genética , Desequilíbrio de Ligação
18.
Front Cell Infect Microbiol ; 13: 1181402, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37249975

RESUMO

Background: Mycoplasma pneumoniae (MP) is a commonly occurring pathogen causing community-acquired pneumonia (CAP) in children. The global prevalence of macrolide-resistant MP (MRMP) infection, especially in Asian regions, is increasing rapidly. However, the prevalence of MRMP and its clinical significance during the COVID-19 pandemic is not clear. Methods: This study enrolled children with molecularly confirmed macrolide-susceptible MP (MSMP) and MRMP CAP from Beijing Children's Hospital Baoding Hospital, Capital Medical University between August 2021 and July 2022. The clinical characteristics, laboratory findings, chest imaging presentations, and strain genotypes were compared between patients with MSMP and MRMP CAP. Results: A total of 520 hospitalized children with MP-CAP were enrolled in the study, with a macrolide resistance rate of 92.7%. Patients with MRMP infection exhibited more severe clinical manifestations (such as dyspnea and pleural effusion) and had a longer hospital stay than the MSMP group. Furthermore, abnormal blood test results (including increased LDH and D-dimer) were more common in the MRMP group (P<0.05). Multilocus variable-number tandem-repeat analysis (MLVA) was performed on 304 samples based on four loci (Mpn13-16), and M3562 and M4572 were the major types, accounting for 74.0% and 16.8% of the strains, respectively. The macrolide resistance rate of M3562 strains was up to 95.1%. Conclusion: The prevalence of MRMP strains in hospitalized CAP patients was extremely high in the Baoding area, and patients infected with MRMP strains exhibited more severe clinical features and increased LDH and D-dimer. M3562 was the predominant resistant clone.


Assuntos
COVID-19 , Infecções Comunitárias Adquiridas , Pneumonia por Mycoplasma , Criança , Humanos , Pneumonia por Mycoplasma/epidemiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Macrolídeos/farmacologia , Relevância Clínica , Pandemias , COVID-19/epidemiologia , Farmacorresistência Bacteriana/genética , Mycoplasma pneumoniae/genética , Infecções Comunitárias Adquiridas/epidemiologia
19.
World J Pediatr ; 19(3): 231-242, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36409451

RESUMO

Monkeypox is a zoonotic disease. Since the first human monkeypox case was detected in 1970, it has been prevalent in some countries in central and western Africa. Since May 2022, monkeypox cases have been reported in more than 96 non-endemic countries and regions worldwide. As of September 14, 2022, there have been more than 58,200 human monkeypox cases, and there is community transmission. The cessation of smallpox vaccination in 1980, which had some cross-protection with monkeypox, resulted in a general lack of immunity to monkeypox, which caused global concern and vigilance. As of September 14, 2022, there are four monkeypox cases in China, including three in Taiwan province and one in Hong Kong city. Previous foreign studies have shown that children are vulnerable to monkeypox and are also at high risk for severe disease or complications. In order to improve pediatricians' understanding of monkeypox and achieve early detection, early diagnosis, early treatment,  and early disposal, we have organized national authoritative experts in pediatric infection, respiratory, dermatology, critical care medicine, infectious diseases, and public health and others to formulate this expert consensus, on the basis of the latest "Clinical management and infection prevention and control for monkeypox" released by The World Health Organization, the "guidelines for diagnosis and treatment of monkeypox (version 2022)" issued by National Health Commission of the People's Republic of China and other relevant documents. During the development of this consensus, multidisciplinary experts have repeatedly demonstrated the etiology, epidemiology, transmission, clinical manifestations, laboratory examinations, diagnosis, differential diagnosis, treatment, discharge criteria, prevention, disposal process, and key points of prevention and control of suspected and confirmed cases.


Assuntos
Mpox , Humanos , Criança , Mpox/diagnóstico , Mpox/epidemiologia , Mpox/prevenção & controle , Saúde Pública , Diagnóstico Diferencial , Vacinação , China/epidemiologia
20.
J Clin Microbiol ; 50(11): 3757-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22933595

RESUMO

We describe a multiplex PCR assay to detect the Mycobacterium tuberculosis Beijing genotype variant B0/W148, which is considered a "successful" clone of M. tuberculosis, widespread in Russia. Specificity and sensitivity of the assay were 100% based on the analysis of a collection of 516 M. tuberculosis isolates of different genotypes and origins. This assay may be used for accurate and simple detection and surveillance of this clinically and epidemiologically important variant of M. tuberculosis.


Assuntos
Técnicas Bacteriológicas/métodos , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/diagnóstico , Métodos Epidemiológicos , Genótipo , Humanos , Programas de Rastreamento/métodos , Mycobacterium tuberculosis/genética , Federação Russa , Sensibilidade e Especificidade , Tuberculose/microbiologia
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