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Objective: To explore the association between the variant mutations within embB and ubiA, and the degree of ethambutol (EMB) resistance of Mycobacterium tuberculosis (M. tuberculosis) isolates. Methods: A total of 146 M. tuberculosis isolates were used to determine the minimum inhibitory concentrations (MICs) of EMB with a 96-well microplate-based assay. The mutations within embB and ubiA among these isolates were identified with DNA sequencing. Moreover, a multivariate regression model and a computer model were established to assess the effects of mutations on EMB resistance. Results: Our data showed that overall 100 isolates exhibited 28 mutated patterns within the sequenced embB and ubiA. Statistical analysis indicated that embB mutations Met306Val, Met306Ile, Gly406Ala, and Gln497Arg, were strongly associated with EMB resistance. Of these mutations, Met306Val and Gln497Arg were significantly associated with high-level EMB resistance. Almost all multiple mutations occurred in high-level EMB-resistant isolates. Although the mutation within ubiA accompanied with embB mutation presented exclusively in EMB-resistant isolates, four single ubiA mutations (Ala39Glu, Ser173Ala, Trp175Cys, and Val283Leu) leading to protein instability were observed in EMB-susceptible isolates. Conclusion: This study highlighted the complexity of EMB resistance. Some individual mutations and multiple mutations within embB and ubiA contributed to the different levels of EMB resistance.
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OBJECTIVES@#To examine the reliability and accuracy of Walker's model for estimating the sex of Han adults in western China by using cranium three-dimensional (3D) CT reconstruction, and to study the suitable cranial sex estimation model for Han people in western China.@*METHODS@#A total of 576 cranial CT 3D reconstructed images from Hanzhong Hospital in Shaanxi Province from 2017 to 2021 were collected. These images were divided into the experimental group with 486 samples and the validation group with 90 samples. Walker's model was used by observer 1 to estimate the sex of experimental group samples. The logistic function applicable to Han people in western China was corrected by observer 1. The 90 samples in the validation group were scored and substituted into the modified logistic function to complete the back substitution test by observer 1, 2 and 3.@*RESULTS@#The accuracy of sex estimation of Han adults in western China was 63.2%-77.2% by applying Walker's model. The accuracy of modified logistic function was 82.9%. The accuracy of sex estimation through back substitution test by 3 observers was 75.6%-91.1%, with a Kappa value of 0.689 (P<0.05) for inter-observer consistency and 0.874 (P<0.05) for intra-observer consistency.@*CONCLUSIONS@#There are great differences in bone characteristics among people from different regions. The modified logistic function can achieve higher accuracy in Han adults in western China.
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Humanos , Adulto , Reproducibilidad de los Resultados , Determinación del Sexo por el Esqueleto/métodos , Antropología Forense , Cráneo/anatomía & histología , Imagenología Tridimensional , China , Tomografía Computarizada por Rayos XRESUMEN
Objective: To assess the relationship between the variant rpoB mutations and the degree of rifampin (RIF)/rifabutin (RFB) resistance in Mycobacterium tuberculosis (M. tuberculosis). Methods: We analyzed the whole rpoB gene in 177 M. tuberculosis clinical isolates and quantified their minimum inhibitory concentrations (MICs) using microplate-based assays. Results: The results revealed that of the 177 isolates, 116 were resistant to both RIF and RFB. There were 38 mutated patterns within the sequenced whole rpoB gene of the 120 isolates. Statistical analysis indicated that mutations, S450L, H445D, H445Y, and H445R, were associated with RIF and RFB resistance. Of these mutations, S450L, H445D, and H445Y were associated with high-level RIF and RFB MIC. H445R was associated with high-level RIF MIC, but not high-level RFB MIC. D435V and L452P were associated with only RIF, but not RFB resistance. Q432K and Q432L were associated with high-level RFB MIC. Several single mutations without statistical association with rifamycin resistance, such as V170F, occurred exclusively in low-level RIF but high-level RFB resistant isolates. Additionally, although cross-resistance to RIF and RFB is common, 21 RIF-resistant/RFB-susceptible isolates were identified. Conclusion: This study highlighted the complexity of rifamycin resistance. Identification of the rpoB polymorphism will be helpful to diagnose the RIF-resistant tuberculosis that has the potential to benefit from a treatment regimen including RFB.
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OBJECTIVE: To investigate the mutations within the whole rpoB gene of Mycobacterium tuberculosis and analyze their effects on rifampin (RIF) resistance based on crystal structure. METHODS: We sequenced the entire rpoB gene in 175 tuberculosis isolates and quantified their minimum inhibitory concentrations using microplate-based assays. Additionally, the structural interactions between wild-type/mutant RpoB and RIF were also analyzed. RESULTS: Results revealed that a total of 34 mutations distributed across 17 different sites within the whole rpoB gene were identified. Of the 34 mutations, 25 could alter the structural interaction between RpoB and RIF and contribute to RIF resistance. Statistical analysis showed that S450L, H445D, H445Y and H445R mutations were associated with high-level RIF resistance, while D435V was associated with moderate-level RIF resistance. CONCLUSION: Some mutations within the rpoB gene could affect the interaction between RpoB and RIF and thus are associated with RIF resistance. These findings could be helpful to design new antibiotics and develop novel diagnostic tools for drug resistance in TB.
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In this study, the colonization, diversity and relative abundance of arbuscular mycorrhizal fungi(AMF) in the roots of Panax quinquefolius in different habitats of Shandong province were analyzed by staining-microscopy and high-throughput sequencing. The data were analyzed by bioinformatics tools and statistical software. The results showed that the roots of P. quinquefolius in different habitats were colonized by AMF with different rates and intensities. The AMF in roots of P. quinquefolius belong to three genera, three families, three orders, one class and one phylum. At the level of order, the AMF mainly included Paraglomerales(52.48%), Glomerales(25.60%) and Archaeosporales(3.08%). At the level of family, the AMF were dominated by Paraglomeraceae(52.48%), Glomeraceae(18.94%) and Claroideoglomeraceae(3.05%). At the level of genus, Paraglomus(51.46%), Glomus(20.01%) and Claroideoglomus(3.52%) accounted for a large proportion, of which Paraglomus and Glomus were dominant. Cluster analysis showed that the AMF in roots of P. quinquefolius with close geographical locations could be clustered together. In this study, the diversity and dominant germplasm resources of AMF in roots of P. quinquefolius cultivated in the main producing areas were identified, which provi-ded basic data for revealing the quality formation mechanism of P. quinquefolius medicinal materials from the perspective of environment.
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Humanos , Hongos , Glomeromycota , Micorrizas/genética , Panax , Raíces de Plantas , Microbiología del SueloRESUMEN
Biochar is a kind of solid material with high aromatization and rich in carbon, which is formed by pyrolysis of biomass at high temperature(250-700 ℃) under anoxic or hypoxic conditions. It has the characteristics of large specific surface area and rich pores. In recent years, as a good soil conditioner, biochar has gradually improved its advantages in improving soil rhizosphere micro ecological environment, promoting plant growth and development, and enhancing plant resistance, etc. It has been proved that biochar can affect the growth and development of plants by improving soil physical and chemical properties, adjusting microbial community structure, participating in the metabolic process in plants, and inducing plants to enhance resistance. This paper summarized the research progress of biochar application in agriculture and introduced the ecological effects and mechanism of biochar on plant seed germination, seedling growth, crop yield and stress resistance. Combined with the characteristics of Chinese materia medica, this paper expounds the application potential of biochar in improving the content of secondary metabolites of Chinese materia medica and alleviating continuous cropping obstacles of Chinese materia medica, etc. In the future, it is necessary to strengthen the research of biochar in the biosynthesis of secondary metabolites, allelopathy and heavy metal stress of medicinal plants, so as to provide reference for the application of biochar in the cultivation of Chinese materia medica.
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Humanos , Agricultura , Carbón Orgánico , China , Medicamentos Herbarios Chinos , Materia MedicaRESUMEN
Objective: To evaluate the application of island flap and combined flap in one-stage reconstruction of nasal alae defects after external nasal tumor resection. Methods: Data of 11 patients with perforating or full-thickness defects of the alae after nasal tumor resection in XuanWu Hospital, Capital Medical University between June 2016 and February 2021 were analyzed retrospectively. There were 7 males and 4 females, and the ages ranged from 51 to 89 years. Island flap, island flap combined with nasolabial flap or V-Y advancement flap, and island flap combined with bilobed flap were applied according to the range of defects. Descriptive statistical method was applied to analyze the treatment effects. Results: All flaps of the 11 patients were successful survival and the incisions were primary healing. Being followed up for 5 to 59 months, the patients had satisfying appearance and ventilation function, and no tumor relapsed. Conclusion: For the patients with nasal alae defects after external nose tumor resection, selecting suitable island skin flap or combined skin flap can be used to reconstruct the ideal nasal appearance and function of the nose.
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Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nariz/cirugía , Neoplasias Nasales/cirugía , Procedimientos de Cirugía Plástica , Estudios Retrospectivos , Rinoplastia , Trasplante de Piel , Colgajos QuirúrgicosRESUMEN
In this study, the infection of root arbuscular mycorrhizal fungi(arbuscular mycorrhizal fungi, AMF of Panax quinquefolium in Shandong province was investigated, and the distribution characteristics and infection regularity of AMF were found out. The AMF of P. quinquefolium roots in different habitats was examined by alkali dissociation-trypickin blue staining method to study the infection rate and infection intensity. The contents of ginsenoside(Rb_1, Re, Rg_1, Rb_2, Rd and Rh_1) in the roots of P. quinquefolium was determined by HPLC. The experimental data were SPSS 17.0 statistical software for One-way analysis of variance, cluster analysis and correlation analysis. The results showed that the AMF infection in roots of P. quinquefolium, and there were obvious structures such as hyphae, arbuscular branches and vesicles, and the AMF infection rate and infection intensity showed obvious spatial and temporal heterogeneity with the growth age and origin of P. quinquefolium. The infection rate of AMF in roots of P. quinquefolium from 1 to 3 years increased significantly with the increase of growth years(P<0.05). The infection intensity and infection rate of P. quinquefolium showed a similar change trend, the AMF infection rate and infection intensity reached the highest level in the third year. Cluster analysis showed that the infection rates of roots of P. quinquefolium in similar geographical locations could be clustered together. Correlation analysis showed that the AMF infection rate of P. quinquefolium root was significantly positively correlated with the infection intensity, and the AMF infection rate and infection intensity were significantly positively correlated with the contents of ginsenoside Rg_1, Re and Rb_1. This study explored the distribution characteristics and regularity of AMF in roots of P. quinquefolium under the protected cultivation conditions, and provided basic data for ecological cultivation of P. quinquefolium and research and development of biological bacterial fertilizer.
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Fertilizantes , Hongos , Ginsenósidos , Micorrizas , Panax , Raíces de PlantasRESUMEN
BACKGROUND@#Transcranial alternating current stimulation (tACS) offers a new approach for adult patients with major depressive disorder (MDD). The study is to evaluate the efficacy and safety of tACS treating MDD.@*METHODS@#This is an 8-week, double-blind, randomized, placebo-controlled study. Ninety-two drug-naive patients with MDD aged 18 to 65 years will receive 20 daily 40-min, 77.5-Hz, 15-mA sessions of active or sham tACS targeting the forehead and both mastoid areas on weekdays for 4 consecutive weeks (week 4), following a 4-week observation period (week 8). The primary outcome is the remission rate defined as the 17-item Hamilton depression rating scale (HDRS-17) score ≤7 at week 8. Secondary outcomes are the rates of response at weeks 4 and 8 and rate of remission at week 4 based on HDRS-17, the proportion of participants having improvement in the clinical global impression-improvement, the change in HDRS-17 score (range, 0-52, with higher scores indicating more depression) over the study, and variations of brain imaging and neurocognition from baseline to week 4. Safety will be assessed by vital signs at weeks 4 and 8, and adverse events will be collected during the entire study.@*DISCUSSION@#The tACS applied in this trial may have treatment effects on MDD with minimal side effects.@*TRIAL REGISTRATION@#Chinese Clinical Trial Registry, ChiCTR1800016479; http://www.chictr.org.cn/showproj.aspx?proj=22048.
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OBJECTIVES: To explore the prevalence, risk and genetic characteristics of drug-resistant tuberculosis (TB) from a tertiary care TB hospital in China. PATIENTS AND METHODS: We carried out a retrospective study including isolates from 189 patients with pulmonary TB at Fuzhou Pulmonary Hospital. All isolates from these patients were subjected to drug susceptibility testing and genotyping. For drug-resistant isolates, DNA sequencing was used to investigate mutations in 12 loci, including katG, inhA, oxyR-ahpC, rpoB, rpsL, rrs 1 (nucleotides 388-1084 of rrs), embB, tlyA, eis, rrs 2 (nucleotides 1158-1674 of rrs), gyrA and gyrB. RESULTS: Among 189 isolates, 28.6% were resistant to at least one of the seven anti-TB drugs, including isoniazid (INH), rifampin (RIF), streptomycin (STR), ethambutol (EMB), capreomycin (CAP), kanzmycin (KAN) and ofloxacin (OFX). The proportion of multidrug-resistant TB and extensively drug-resistant TB isolates was 9.5% and 1.1%, respectively. Patients in rural areas as well as previously treated patients showed a significantly increased risk of developing drug resistance. In addition, among these isolates, 111 (58.7%) were Beijing genotype strains, 84 (75.7%) of which belonged to modern Beijing sublineage. There was no association between genotype and drug resistance. The most common mutations were katG315, rpo B531 rpsL43, embB306, rrs1401 and gyrA94. CONCLUSION: These findings provided additional information of drug-resistant TB in China. Previously treated patients and patients in rural areas should receive greater attention owing to their higher risk of developing drug resistance.
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Mycobacterium tuberculosis Beijing genotype strains are widespread globally. However, there has been no systematic study on the association between Beijing genotype and the characteristics of drug resistance. In this study, 359 M. tuberculosis isolates from south China were collected and their background information, genotype diversity and drug resistance was investigated. The results revealed that 66.0% of strains (237/359) were categorised as Beijing genotype. There was no statistical difference between Beijing and non-Beijing genotype strains in terms of patient sex, age, place of residence and treatment history. Drug resistance testing showed that 34.8% (125/359) of isolates were resistant to at least one of the seven drugs tested. The proportions of multidrug-resistant tuberculosis and extensively drug-resistant tuberculosis were 17.0% and 1.4%, respectively. Previously treated patients presented a significantly higher risk of developing drug resistance than new cases. Although the prevalence of drug resistance was higher in Beijing genotype than in non-Beijing genotype strains, there was no significant difference between these two genotypes in the multivariate analysis. Even in re-treated patients, the association of Beijing genotype with drug resistance was not significant. This study provides an insight into genotype diversity and demonstrates the characteristics of drug resistance in Beijing genotype strains, which will be useful in generating efficient tuberculosis prevention and control strategies in China.
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Antituberculosos/farmacología , Farmacorresistencia Bacteriana/genética , Genotipo , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis/epidemiología , Tuberculosis/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/genética , Adulto JovenRESUMEN
OBJECTIVE: This study aimed to characterize the diagnostic and vaccine potential of a novel Mycobacterium tuberculosis antigen Rv0674. METHODS: To evaluate the diagnostic potential and antigenicity of Rv0674, IgG was evaluated using ELISA and interferon (IFN)-γ was done by using ELISpot assay among TB patients and healthy donors. For immunogenicity evaluation, BALB/c mice were immunized with Rv0674. Cytokine production was determined by cytokine release assay using an ELISA kit, and the antibodies were tested using ELISA. RESULTS: The results of serum Elisa tests showed that Rv0674 specific immunoglobulin G (IgG) response was higher in TB patients than negative controls. And Rv0674 had good performance in serological test with sensitivity and specificity of 77.1% and 81.1%, respectively. While it shows poor sensitivity and specificity of 26.23% and 79.69% for IFN-γ tests. In BALB/c mice, Rv0674 adjuvant by DDA/Poly I:C could also induce a high level of IFN-γ, interleukin-2 and interleukin-6 as well as a high IgG titer in both high- and low-dose groups indicating that Rv0674 is essential in humoral and cellular immunity. Moreover, the cytokine profile and IgG isotype characterized Rv0674 as a Th1/Th2-mixed-type protective immunity with the predominance of Th1 cytokines. CONCLUSION: Rv0674 may be a good potential candidate for the development of TB serological diagnosis and a new TB vaccine.
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Antígenos Bacterianos/inmunología , Tuberculosis/inmunología , Adulto , Anciano , Animales , Femenino , Humanos , Inmunidad Celular , Inmunidad Humoral , Masculino , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Tuberculosis/diagnóstico , Adulto JovenRESUMEN
Objective: To study the effect of Morindae Officinalis Radixe extract from different origins on the vascular growth of damaged internodes of zebra fish, so as to discuss regional differences of Morindae Officinalis Radix from different origins. Method: A zebra fish model of internode vascular injury induced by PTK787 was established to study the effect of Morindae Officinalis Radix extract from Guangdong, Guangxi and Fujian on the growth of internode vascular in zebra fish, and detect the number of internode angiogenesis in zebra fish treated with PTK787.On the basis of principal component analysis, relative angiogenesis rate was taken as the index, and the experimental data was analyzed by SPSS 17.0 statistical software. Result: The extract of Morindae Officinalis Radix had a repairing effect on the growth of damaged internode blood vessels of zebra fish, and the extracts of Morindae Officinalis Radix from Guangdong Gaoyao, and Guangdong Yunan, were better than those from other producing areas. The average number of internode angiogenesis was 9, the average length of angiogenesis was 448-504 μm, and the relative rate of angiogenesis was between 7.9% and 8.86%. The results of cluster analysis showed that Morindae Officinalis Radix of 12 different origins were classified into four categories, Guangdong Deqing, and Guangdong Gaoyao, Guangxi Cangwu and Guangxi Cenxi, and Guangdong Yunan, and Guangxi Cangwu could be better clustered. Conclusion: There are obvious regional differences in the pro-angiogenic effect of Morindae Officinalis Radix from different origins. Relevant studies provide basic data for the quality assessment of Morindae Officinalis Radix medicinal materials.
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OBJECTIVE: Macrolide susceptibility and drug resistance mechanisms of clinical non-tuberculous mycobacteria (NTM) isolates were preliminarily investigated for more accurate diagnosis and treatment of the infection in China. METHODS: Four macrolides, including clarithromycin (CLAR), azithromycin (AZM), roxithromycin (ROX), and erythromycin (ERY), were used to test the drug susceptibility of 310 clinical NTM isolates from six provinces of China with the broth microdilution method. Two resistance mechanisms, 23S rRNA and erm, were analyzed with nucleotide sequence analysis. RESULTS: Varied effectiveness of macrolides and species-specific resistance patterns were observed. Most Mycobacterium abscessus subsp. massiliense were susceptible and all M. fortuitum were highly resistant to macrolides. All the drugs, except for erythromycin, exhibited excellent activities against slow-growing mycobacteria, and drug resistance rates were below 22.2%. Only four highly resistant strains harbored 2,058/2,059 substitutions on rrl and none of other mutations were related to macrolide resistance. G2191A and T2221C on rrl were specific for the M. abscessus complex (MABC). Seven sites, G2140A, G2210C, C2217G, T2238C, T2322C, T2404C, and A2406G, were specifically carried by M. avium and M. intracellulare. Three sites, A2192G, T2358G, and A2636G, were observed only in M. fortuitum and one site G2152A was specific for M. gordonae. The genes erm(39) and erm(41) were detected in M. fortuitum and M. abscessus and inducible resistance was observed in relevant sequevar. CONCLUSION: The susceptibility profile of macrolides against NTM was demonstrated. The well-known macrolide resistance mechanisms, 23S rRNA and erm, failed to account for all resistant NTM isolates, and further studies are warranted to investigate macrolide resistance mechanisms in various NTM species.
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Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Macrólidos/farmacología , Mycobacterium/efectos de los fármacos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , China , Regulación Bacteriana de la Expresión Génica , Humanos , Mycobacterium/genética , Polimorfismo GenéticoRESUMEN
The EmbCAB proteins have been considered a target for ethambutol (EMB). Mutations in embCAB are known to confer most EMB resistance. However, the knowledge about the effects of embCAB mutations on the EMB resistance level and about the role of mutation-mutation interactions is limited in China. Here, we sequenced embCAB among 125 Mycobacterium tuberculosis isolates from China and quantified their EMB MICs by testing growth at 10 concentrations. Furthermore, a multivariate regression model was established to assess the effects of both individual mutations and multiple mutations. Our results revealed that in China, 82.6% of EMB-resistant isolates (71/86 isolates) harbored at least one mutation within embCAB Most of the mutations were located in the embB and embA upstream region. Several individual mutations and multiple mutations within this region contributed to the different levels of EMB resistance. Their effects were statistically significant. Additionally, there was an association between high-level EMB resistance and multiple mutations.
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Antituberculosos/farmacología , Proteínas Bacterianas/genética , Etambutol/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , China , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Humanos , Análisis Multivariante , Mutación , Operón , Tuberculosis Pulmonar/microbiologíaRESUMEN
Rapid detection of resistance to the second-line drugs is essential for early initiation of appropriate anti-tubercular treatment regimen among multi-drug tuberculosis (MDR-TB). In this study, we applied a multiplex allele-specific PCR (MAS-PCR) to identify the mutations on codons 90 and 94 of gyrA and nucleotide 1401 of rrs for detecting ofloxacin (OFX) and kanamycin (KAN) resistance in 139 MDR-TB isolates from China. Using the traditional phenotypic method as the reference, MAS-PCR detected resistance to OFX and KAN with sensitivities of 67.3% and 76.5%, respectively, and specificities of 100.0%. Therefore, MAS-PCR assays can be used for rapid detection of second-line drug resistance among MDR-TB in China, enabling early administration of appropriate treatment regimens to the affected MDR-TB patients.
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Técnicas Bacteriológicas , Análisis Mutacional de ADN/métodos , Farmacorresistencia Bacteriana Múltiple/genética , Reacción en Cadena de la Polimerasa Multiplex , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Antituberculosos/uso terapéutico , China , Girasa de ADN/genética , Genotipo , Humanos , Kanamicina/uso terapéutico , Resistencia a la Kanamicina/genética , Pruebas de Sensibilidad Microbiana , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/patogenicidad , Ofloxacino/uso terapéutico , Valor Predictivo de las Pruebas , Proteínas Ribosómicas/genética , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológicoRESUMEN
Genotyping results and DNA sequencing analysis of 235 Mycobacterium tuberculosis (M. tuberculosis) isolates from China indicated that mutations at codon 995 (Pro CCG to Pro CCA) and 701 (Ile ATT to Thr ACT) in lysX gene (Rv1640c), are specific markers for Beijing and modern Beijing strains, respectively. This observation was also confirmed by 24 genomes of M. tuberculosis strains from other countries. Moreover, a simple and fast multiplex allele-specific PCR (MAS-PCR) method for detecting mutations at codon 995 and 701 in lysX has been established and used to screen 235 DNA samples obtained from M. tuberculosis isolates. In all cases, Beijing and modern Beijing strains were identified correctly.
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Proteínas Bacterianas/genética , Técnicas Bacteriológicas , Análisis Mutacional de ADN , Lisina-ARNt Ligasa/genética , Reacción en Cadena de la Polimerasa Multiplex , Mutación , Mycobacterium tuberculosis/genética , Tuberculosis/diagnóstico , Proteínas Bacterianas/química , China , Codón , Marcadores Genéticos , Genotipo , Humanos , Mycobacterium tuberculosis/patogenicidad , Fenotipo , Valor Predictivo de las Pruebas , Conformación Proteica , Estabilidad Proteica , Reproducibilidad de los Resultados , Tuberculosis/microbiologíaRESUMEN
We investigated the spectrum and frequency of mutations in rpsL, rrs, and gidB among 140 multidrug-resistant tuberculosis (MDR-TB) clinical isolates from China. The association between mutations and different genotypes was also analyzed. Our data revealed that 65.7% of MDR-TB were resistant to streptomycin (STR), and 90.2% of STR-resistant isolates were Beijing strains. STR resistance was correlated with Beijing family (P=0.00). Compared with phenotypic data, detection of mutations for the combination of these 3 genes exhibited 94.6% sensitivity, 91.7% specificity, and 93.6% accuracy. The most common mutations in STR-resistant isolates were rpsL128, 262, and rrs514, of which rpsL128 showed association with Beijing lineage (P=0.00). A combination of these 3 mutations can serve as the reliable predictors for STR resistance, showing the sensitivity, specificity, and accuracy of 85.9%, 97.9%, and 90.0%, respectively. Furthermore, gidBA276C, not A615G, was Beijing lineage specific. These findings are useful to develop rapid molecular diagnostic methods for STR resistance in China.
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Antibacterianos/farmacología , Genotipo , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Estreptomicina/farmacología , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/aislamiento & purificación , Adulto JovenRESUMEN
Ethambutol (EMB) plays a pivotal role in the chemotherapy of drug-resistant tuberculosis (TB), including multidrug-resistant tuberculosis (MDR-TB). Resistance to EMB is considered to be caused by mutations in the embCAB operon (embC, embA, and embB). In this study, we analyzed the embCAB mutations among 139 MDR-TB isolates from China and found a possible association between embCAB operon mutation and EMB resistance. Our data indicate that 56.8% of MDR-TB isolates are resistant to EMB, and 82.2% of EMB-resistant isolates belong to the Beijing family. Overall, 110 (79.1%) MDR-TB isolates had at least one mutation in the embCAB operon. The majority of mutations were present in the embB gene and the embA upstream region, which also displayed significant correlations with EMB resistance. The most common mutations occurred at codon 306 in embB (embB306), followed by embB406, embA(-16), and embB497. Mutations at embB306 were associated with EMB resistance. DNA sequencing of embB306-497 was the best strategy for detecting EMB resistance, with 89.9% sensitivity, 58.3% specificity, and 76.3% accuracy. Additionally, embB306 had limited value as a candidate predictor for EMB resistance among MDR-TB infections in China.
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Antituberculosos/farmacología , Proteínas Bacterianas/genética , Etambutol/farmacología , Proteínas de la Membrana/genética , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Pentosiltransferasa/genética , Tuberculosis Resistente a Múltiples Medicamentos/genética , Tuberculosis/microbiología , China , ADN Bacteriano/genética , Humanos , Pruebas de Sensibilidad MicrobianaRESUMEN
?-(1,3)-D-glucan is a core structure of many bioactive fungal polysaccharides. It has drawn intensive attentions in recent because of its multiple bioactivities, particularly the immunomodulatory and antitumorous actions. In this review, we introduced the studies of structure-activity correlation of these ?-(1,3)-D-glucans, particularly the contributions of main backbone, branch degree and residues, molecular weight and conformation to the activities. We also summarized the recent progress in the detective methods for both quantitation and qualification using limulus G factor assay,galactosyl ceramide ELISA and etc.