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1.
Insect Sci ; 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37830269

RESUMEN

Bumblebees are important pollinators in agricultural ecosystems, but their abundance is declining globally. There is an urgent need to protect bumblebee health and their pollination services. Bumblebees possess specialized gut microbiota with potential to be used as probiotics to help defend at-risk bumblebee populations. However, evidence for probiotic benefits on bumblebees is lacking. Here, we evaluated how supplementation with Lactobacillus melliventris isolated from bumblebee gut affected the colony development of Bombus terrestris. This native strain colonized robustly and persisted long-term in bumblebees, leading to a significantly higher quality of offspring. Subsequently, the tyrosine pathway was upregulated in the brain and fat body, while the Wnt and mTOR pathways of the gut were downregulated. Notably, the field experiment in the greenhouse revealed the supplementation of L. melliventris led to a 2.5-fold increase in the bumblebee survival rate and a more than 10% increase in the number of flowers visited, indicating a better health condition and pollination ability in field conditions. Our study represents a first screening for the potential use of the native gut member, L. melliventris, as probiotic strains in hive supplement for bumblebee breeding, which may be a practical approach to improve immunity and hive health.

2.
Emerg Infect Dis ; 29(3): 667-669, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36823712

RESUMEN

We report a case of Babesia microti infection in an immunocompetent child <5 years of age that caused fever and severe intravascular hemolysis. Physicians in China should be aware of babesiosis, especially in the differential diagnosis of immune hemolytic anemia with negative results for antiglobulin tests.


Asunto(s)
Babesia microti , Babesiosis , Humanos , Niño , Hemólisis , Babesiosis/diagnóstico , China , Fiebre
3.
Antimicrob Agents Chemother ; 66(9): e0041422, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-35972242

RESUMEN

Drug-resistant Neisseria gonorrhoeae is a serious global health concern. New drugs are needed that can overcome existing drug resistance and limit the development of new resistances. Here, we describe the small molecule tricyclic pyrimidoindole JSF-2414 [8-(6-fluoro-8-(methylamino)-2-((2-methylpyrimidin-5-yl)oxy)-9H-pyrimido[4,5-b]indol-4-yl)-2-oxa-8-azaspiro[4.5]decan-3-yl)methanol], which was developed to target both ATP-binding regions of DNA gyrase (GyrB) and topoisomerase (ParE). JSF-2414 displays potent activity against N. gonorrhoeae, including drug-resistant strains. A phosphate pro-drug, JSF-2659, was developed to facilitate oral dosing. In two different animal models of Neisseria gonorrhoeae vaginal infection, JSF-2659 was highly efficacious in reducing microbial burdens to the limit of detection. The parent molecule also showed potent in vitro activity against high-threat Gram-positive organisms, and JSF-2659 was shown in a deep tissue model of vancomycin-resistant Staphylococcus aureus (VRSA) and a model of Clostridioides difficile-induced colitis to be highly efficacious and protective. JSF-2659 is a novel preclinical drug candidate against high-threat multidrug resistant organisms with low potential to develop new resistance.


Asunto(s)
Gonorrea , Staphylococcus aureus Resistente a Meticilina , Profármacos , Adenosina Trifosfato , Animales , Antibacterianos/química , Antibacterianos/farmacología , Girasa de ADN/genética , Farmacorresistencia Bacteriana , Femenino , Gonorrea/tratamiento farmacológico , Metanol/farmacología , Staphylococcus aureus Resistente a Meticilina/metabolismo , Pruebas de Sensibilidad Microbiana , Neisseria gonorrhoeae , Fosfatos/farmacología , Profármacos/farmacología , Inhibidores de Topoisomerasa II/farmacología
4.
RSC Adv ; 12(31): 19875-19884, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35865193

RESUMEN

Silicon dioxide (SiO2) has attracted much attention as an ideal coating material for iron (Fe)-based soft magnetic powder cores (SMPCs). However, maintaining the integrity and uniformity of Fe-based/SiO2 core-shell heterostructures is still a challenge. The evolution mechanism of core-shell heterostructures determines the performance of Fe-based SMPCs. Herein, the evolution of the core-shell structures and heterogeneous interfaces of Fe-Si@SiO2 SMPCs with axial pressure and the influence of the evolution on the SMPCs performance were investigated. The results show that in the axial pressure range of 10-15 kN, the core-shell heterostructures were gradually integrated, whereas the SiO2 insulation coatings underwent an amorphous-to-crystalline transformation. At axial pressure above 16 kN, the Fe-Si powder melted partially, and the core-shell heterostructure collapsed due to overheating, caused by the gradient temperature field during the hot-press sintering. When the core-shell heterostructure was intact, the Fe-Si@SiO2 SMPCs showed a permeability of over 38 with a wide and stable frequency range of 100-300 kHz, a saturation magnetisation of 231.7 emu g-1, resistivity of 0.8 mΩ cm and total loss of 704.7 kW m-3 at 10 mT and 100 kHz. When the core-shell heterostructure was destroyed, the resistivity dropped dramatically and the loss increased to 765.0 and 897.4 kW m-3. These results show the relationship between the core-shell heterostructure of Fe-Si@SiO2 SMPCs, axial pressure and magnetic properties, which would be vital in achieving high power density, high efficiency and miniaturisation in SMPCs.

5.
Infect Dis Poverty ; 11(1): 60, 2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35655325

RESUMEN

BACKGROUND: Leishmaniasis is a serious neglected tropical disease that may lead to life-threatening outcome, which species are closely related to clinical diagnosis and patient management. The current Leishmania species determination method is not appropriate for clinical application. New Leishmania species identification tool is needed using clinical samples directly without isolation and cultivation of parasites. METHODS: A probe-based allele-specific real-time PCR assay was established for Leishmania species identification between Leishmania donovani and L. infantum for visceral leishmaniasis (VL) and among L. major, L. tropica and L. donovani/L. infantum for cutaneous leishmaniasis (CL), targeting hypoxanthine-guanine phosphoribosyl transferase (HGPRT) and spermidine synthase (SPDSYN) gene with their species-specific single nucleotide polymorphisms (SNPs). The limit of detection of this assay was evaluated based on 8 repeated tests with intra-assay standard deviation < 0.5 and inter-assay coefficients of variability < 5%. The specificity of this assay was tested with DNA samples obtained from Plasmodium falciparum, Toxoplasma gondii, Brucella melitensis and Orientia tsutsugamushi. Total 42 clinical specimens were used to evaluate the ability of this assay for Leishmania species identification. The phylogenetic tree was constructed using HGPRT and SPDSYN gene fragments to validate the performance of this assay. RESULTS: This new method was able to detect 3 and 12 parasites/reaction for VL and CL respectively, and exhibited no cross-reaction with P. falciparum, T. gondii, B. melitensis, O. tsutsugamushi and non-target species of Leishmania. Twenty-two samples from VL patients were identified as L. donovani (n = 3) and L. infantum (n = 19), and 20 specimens from CL patients were identified as L. major (n = 20), providing an agreement of 100% compared with sequencing results. For further validation, 29 sequences of HGPRT fragment from nine Leishmania species and 22 sequences from VL patients were used for phylogenetic analysis, which agreed with the results of this new method. Similar results were obtained with 43 sequences of SPDSYN fragment from 18 Leishmania species and 20 sequences from CL patients. CONCLUSIONS: Our assay provides a rapid and accurate tool for Leishmania species identification which is applicable for species-adapted therapeutic schedule and patient management.


Asunto(s)
Leishmania donovani , Leishmaniasis Cutánea , Leishmaniasis Visceral , Malaria Falciparum , Alelos , Humanos , Hipoxantina Fosforribosiltransferasa , Leishmaniasis Visceral/diagnóstico , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa
7.
PLoS Negl Trop Dis ; 15(12): e0010025, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34919557

RESUMEN

Pneumocystis pneumonia (PCP) and pulmonary toxoplasmosis (PT) are caused by Pneumocystis jirovecii and Toxoplasma gondii. The clinical symptoms and imaging of PCP and PT are indistinguishable. A duplex qPCR was developed to differentiate between these two pathogens. In testing 92 clinical samples to validate the performance of this method for P. jirovecii detection, it identified 31 positive samples for P. jirovecii infection, consistent with clinical diagnosis. Among the remainder of the 61 clinical samples with suspected PCP, yet showing as negative by the conventional PCR diagnosis approach, 6 of them proved positive using our new assay. Our new approach also produced similar results in identification of T. gondii infections, giving a result of 2 positive and 20 negative in clinical samples. An investigation was undertaken on the prevalence of P. jirovecii and T. gondii infections using 113 samples from lung infection patients. 9% (10/113) were shown to be positive with infections of P. jirovecii, 2% with T. gondii (2/113) and 5% (6/113) were co-infected with both pathogens. Although this duplex qPCR can detect individual P. jirovecii and T. gondii infection, and co-infection of both pathogens, further large-scale investigations are needed to validate its performance, especially in T. gondii detection. Our assay provides a rapid and accurate tool for PCP and PT diagnosis in immunocompromised population and clinical surveillance of these infections in patients with no immune defects.


Asunto(s)
Enfermedades Pulmonares/microbiología , Enfermedades Pulmonares/parasitología , Pneumocystis carinii/aislamiento & purificación , Neumonía por Pneumocystis/microbiología , Reacción en Cadena de la Polimerasa/métodos , Toxoplasma/aislamiento & purificación , Toxoplasmosis/parasitología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Huésped Inmunocomprometido , Lactante , Pulmón/microbiología , Pulmón/parasitología , Enfermedades Pulmonares/diagnóstico , Masculino , Persona de Mediana Edad , Pneumocystis carinii/genética , Neumonía por Pneumocystis/diagnóstico , Toxoplasma/genética , Toxoplasmosis/diagnóstico , Adulto Joven
8.
Angew Chem Int Ed Engl ; 60(41): 22172-22177, 2021 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-34355488

RESUMEN

Natural products are a major source of new antibiotics. Here we utilize biosynthetic instructions contained within metagenome-derived congener biosynthetic gene clusters (BGCs) to guide the synthesis of improved antibiotic analogues. Albicidin and cystobactamid are the first members of a new class of broad-spectrum ρ-aminobenzoic acid (PABA)-based antibiotics. Our search for PABA-specific adenylation domain sequences in soil metagenomes revealed that BGCs in this family are common in nature. Twelve BGCs that were bio-informatically predicted to encode six new congeners were recovered from soil metagenomic libraries. Synthesis of these six predicted structures led to the identification of potent antibiotics with changes in their spectrum of activity and the ability to circumvent resistance conferred by endopeptidase cleavage enzymes.


Asunto(s)
Ácido 4-Aminobenzoico/síntesis química , Antibacterianos/síntesis química , Productos Biológicos/síntesis química , Ácido 4-Aminobenzoico/química , Antibacterianos/química , Productos Biológicos/química , Estructura Molecular , Compuestos Orgánicos/síntesis química , Compuestos Orgánicos/química , Xanthomonas/química
9.
BMC Gastroenterol ; 21(1): 305, 2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-34332527

RESUMEN

BACKGROUND: Gongylonema pulchrum is a zoonotic parasite rarely found in humans. To date, there have been no reports on the carcinogenic properties of G. pulchrum, and there are few reports overall on the relationship between esophageal cancer and parasites. CASE PRESENTATION: This report describes the first case of esophageal gongylonemiasis coexisting with early esophageal cancer. The patient had no high-risk factors for esophageal cancer, such as smoking, flushing after drinking, or tumor history. We speculate the existence of unknown links between esophageal cancer and parasitic infection in this patient. DISCUSSION AND CONCLUSIONS: We report the first case of a human presenting both esophageal G. pulchrum infection and esophageal squamous cell carcinoma with the hope that it may provide evidence for a new hypothesis of tumorigenesis.


Asunto(s)
Enfermedades del Esófago , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Infecciones por Spirurida , Spiruroidea , Animales , Humanos
10.
Anim Biotechnol ; 32(5): 602-609, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32163017

RESUMEN

In this study, embryos of Sepiella japonica from eye primordium formation to the larval growing stage were collected and used for RNA-Seq analysis. A total of 183,542,186 clean reads were assembled de novo into 58,054 unigenes consisting of 54,118,228 bp, with the average length at 932 bp and the N50 at 1667 bp. 21,469 (36.98%) unigenes were annotated at least in one of four databases including non-redundant protein (NR), Swiss-Prot, clusters of orthologous groups of proteins (KOG) and Kyoto Encyclopedia of Genes and Genomes (KEGG). 4460 (7.68%) unigenes were annotated in all databases. Analysis of differentially expressed genes (DEGs) was carried out on embryos at Eye primordium formation stage (SJ1), organ differentiation stage (SJ2), and hatching stage (SJ3). Overall, the current study provided the de novo assembly of S. japonica transcriptome and identified the DEGs and pathways during embryonic development, which will provide a fundamental genetic resource for further functional research.


Asunto(s)
Decapodiformes , Desarrollo Embrionario/genética , Transcriptoma , Animales , Decapodiformes/embriología , Decapodiformes/genética , Embrión no Mamífero , RNA-Seq , Transcriptoma/genética
11.
Front Cell Infect Microbiol ; 10: 581639, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33117735

RESUMEN

Leishmaniasis is still a serious neglected tropical disease that may cause death in infected individuals. At present, the clinical diagnosis and treatment monitoring still rely on parasitological culture and microscopy that needs experienced technicians. The low sensitivity and inconvenience of microscopic examination could cause misdiagnosis and relapse of leishmaniasis. There is an urgent need for developing a sensitive and easily operated diagnostic method for the diagnosis and disease management of leishmaniasis. Thus, a quantitative real-time PCR (qPCR) based on the conversed regions of kinetoplast minicircle DNA (mkDNA) of Leishmania spp. was developed to detect different species of Leishmania. The designed mkDNA-based qPCR was able to detect as low as one copy of Leishmania mkDNA or DNA from single parasite. It also detected Pan-Leishmania protozoa including Leishmania donovani, Leishmania infantum and Leishmania major without cross-reaction with other pathogen DNAs available in our lab. This method was clinically applied to quantitatively detect skin lesion samples from 20 cutaneous leishmaniasis (CL) and bone marrow and/or PBMC samples from 30 current and cured visceral leishmaniasis (VL) patients, and blood samples from 11 patients with other infections and 5 normal donors as well. Total 20 skin lesion samples from current CL patients and 20 bone marrow and/or PBMC samples from current VL patients were all detected as positive with qPCR without cross-reaction with samples from patients with malaria, brucellosis and dengue or normal donors. Two VL patients with parasite converted to microscopically negative after treatment were detected positive with qPCR. The patients with bigger skin lesion in CL and higher level of immunoglobulin or splenomegaly in VL, had the higher parasite load detected by qPCR. The parasite load was significantly reduced after treatment. In conclusion, the mkDNA-based qPCR assay that we developed in this study can be used not only for diagnosis of both cutaneous and visceral leishmaniasis with high sensitivity and specificity, but also for evaluating the severity and treatment efficacy of this disease, presenting a rapid and accurate tool for clinical surveillance, treatment monitoring and the end point determination of leishmaniasis.


Asunto(s)
ADN de Cinetoplasto , Leucocitos Mononucleares , ADN de Cinetoplasto/genética , ADN Protozoario/genética , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , Sensibilidad y Especificidad , Resultado del Tratamiento
12.
BMC Musculoskelet Disord ; 21(1): 230, 2020 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-32284062

RESUMEN

BACKGROUND: Femoral neck fractures are one of the problems in clinical treatment. The prognosis is uncertain. Currently, No internal fixation method is superior to other internal fixation methods in the treatment of femoral neck fractures. Therefore, the internal fixation system needs to be further explored. The aim of this study was to compare clinical outcomes of femoral neck dynamic compression locking system (DCLS) and multiple cannulated compression screws(MCCS) in the treatment of femoral neck fractures. METHODS: A prospective analysis of 54 cases of femoral neck fractures treated with either a DCLS (n = 28) or MCCS (n = 26) was conducted between December 2015 and November 2017 in authors' hospitals. The perioperative and postoperative parameters of the two groups were recorded and evaluated. RESULTS: Fifty-four patients were followed up for 24-47 months. The etiology was caused by a fall. There was no significant difference in follow-up time, operation time, incision length, surgical blood loss, the incidence of perioperative and postoperative healing complications, and mobility in the two groups (all P > 0.05). The Harris score, fracture healing time, femoral neck shortening, partial weight-bearing time and complete weight-bearing time were significantly better in the DCLS group than in the MCCS group (all P < 0.05). The fracture healing rate in the DCLS group was higher than that in the MCCS group. CONCLUSIONS: The DCLS and MCCS might be equally effective in terms of operation time, incision length, surgical blood loss, the incidence of perioperative and postoperative healing complications, and mobility in the treatment of femoral neck fractures. However, the DCLS is superior to the MCCS in Harris score, fracture healing time, femoral neck shortening, weight-bearing time and fracture healing rate. So, DCLS deserves further study.


Asunto(s)
Tornillos Óseos , Fracturas del Cuello Femoral/cirugía , Cuello Femoral/cirugía , Fijación Interna de Fracturas/métodos , Anciano , Pérdida de Sangre Quirúrgica/prevención & control , Femenino , Cuello Femoral/diagnóstico por imagen , Curación de Fractura , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Complicaciones Posoperatorias , Presión , Estudios Prospectivos , Falla de Prótesis/etiología , Radiografía , Resultado del Tratamiento
13.
Cell Chem Biol ; 27(5): 560-570.e10, 2020 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-32197094

RESUMEN

Published Mycobacterium tuberculosis ß-ketoacyl-ACP synthase KasA inhibitors lack sufficient potency and/or pharmacokinetic properties. A structure-based approach was used to optimize existing KasA inhibitor DG167. This afforded indazole JSF-3285 with a 30-fold increase in mouse plasma exposure. Biochemical, genetic, and X-ray studies confirmed JSF-3285 targets KasA. JSF-3285 offers substantial activity in an acute mouse model of infection and in the corresponding chronic infection model, with efficacious reductions in colony-forming units at doses as low as 5 mg/kg once daily orally and improvement of the efficacy of front-line drugs isoniazid or rifampicin. JSF-3285 is a promising preclinical candidate for tuberculosis.


Asunto(s)
3-Oxoacil-(Proteína Transportadora de Acil) Sintasa/antagonistas & inhibidores , Antituberculosos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis/tratamiento farmacológico , 3-Oxoacil-(Proteína Transportadora de Acil) Sintasa/metabolismo , Animales , Antituberculosos/química , Antituberculosos/uso terapéutico , Proteínas Bacterianas/metabolismo , Descubrimiento de Drogas , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/uso terapéutico , Femenino , Humanos , Ratones , Modelos Moleculares , Mycobacterium tuberculosis/enzimología
14.
Cell Chem Biol ; 27(2): 172-185.e11, 2020 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-31711854

RESUMEN

The triazine antitubercular JSF-2019 was of interest due to its in vitro efficacy and the nitro group shared with the clinically relevant delamanid and pretomanid. JSF-2019 undergoes activation requiring F420H2 and one or more nitroreductases in addition to Ddn. An intrabacterial drug metabolism (IBDM) platform was leveraged to demonstrate the system kinetics, evidencing formation of NO⋅ and a des-nitro metabolite. Structure-activity relationship studies focused on improving the solubility and mouse pharmacokinetic profile of JSF-2019 and culminated in JSF-2513, relying on the key introduction of a morpholine. Mechanistic studies with JSF-2019, JSF-2513, and other triazines stressed the significance of achieving potent in vitro efficacy via release of intrabacterial NO⋅ along with inhibition of InhA and, more generally, the FAS-II pathway. This study highlights the importance of probing IBDM and its potential to clarify mechanism of action, which in this case is a combination of NO⋅ release and InhA inhibition.


Asunto(s)
Antituberculosos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Triazinas/química , Animales , Antituberculosos/farmacocinética , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana/efectos de los fármacos , Ácido Graso Sintasas/antagonistas & inhibidores , Ácido Graso Sintasas/metabolismo , Femenino , Semivida , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/metabolismo , Óxido Nítrico/metabolismo , Oxidorreductasas/antagonistas & inhibidores , Oxidorreductasas/metabolismo , Triazinas/farmacocinética , Triazinas/farmacología
15.
Med Sci Monit ; 25: 7451-7458, 2019 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-31584928

RESUMEN

BACKGROUND Curcumin is a polyphenol compound extracted from the root of the herb Curcuma longa, which is used in traditional Chinese medicine (TCM). Worldwide, colorectal carcinoma (CRC) is an increasing cause of morbidity and mortality. This study aimed to investigate the effects of increasing concentrations of curcumin on cell viability, proliferation, and apoptosis of SW620 human colonic adenocarcinoma cells cultured in vitro, and the signaling pathways involved. MATERIAL AND METHODS SW620 human colonic adenocarcinoma cells were cultured in curcumin at concentrations of 0, 4, 8, 16, and 32 µmol/l for 48 hours. Specific small interfering RNA (siRNA) was transfected into SW620 cells to silence the expression of caudal type homeobox-2 (CDX2). Cell viability was measured using the MTT assay. Flow cytometry evaluated cell apoptosis. Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR) were used to assess the nuclear translocation of b-catenin and the activation of Wnt signaling. RESULTS Curcumin reduced cell viability and increased apoptosis of SW620 human colonic adenocarcinoma cells in a dose-dependent way, and increased the expression of CDX2 but decreased ß-catenin nuclear translocation and the expression of Wnt3a, c-Myc, survivin, and cyclin D1. CDX2 silencing significantly reduced the effects of curcumin on SW620 human colonic adenocarcinoma cells. The nuclear translocation of ß-catenin, and expression levels of Wnt3a, c-Myc, survivin, and cyclin D1 were significantly higher in CDX2-silenced SW620 cells. CONCLUSIONS Curcumin reduced cell viability and increased apoptosis in SW620 human colonic adenocarcinoma cells by restoring CDX2, which inhibited the Wnt/ß-catenin signaling pathway.


Asunto(s)
Factor de Transcripción CDX2/metabolismo , Neoplasias del Colon/tratamiento farmacológico , Curcumina/farmacología , Vía de Señalización Wnt/efectos de los fármacos , beta Catenina/metabolismo , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Apoptosis/efectos de los fármacos , Factor de Transcripción CDX2/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Relación Dosis-Respuesta a Droga , Humanos
16.
ACS Infect Dis ; 5(12): 2148-2163, 2019 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-31625383

RESUMEN

Tuberculosis, caused by Mycobacterium tuberculosis (M. tuberculosis), kills 1.6 million people annually. To bridge the gap between structure- and cell-based drug discovery strategies, we are pioneering a computer-aided discovery paradigm that merges structure-based virtual screening with ligand-based, machine learning methods trained with cell-based data. This approach successfully identified N-(3-methoxyphenyl)-7-nitrobenzo[c][1,2,5]oxadiazol-4-amine (JSF-2164) as an inhibitor of purified InhA with whole-cell efficacy versus in vitro cultured M. tuberculosis. When the intrabacterial drug metabolism (IBDM) platform was leveraged, mechanistic studies demonstrated that JSF-2164 underwent a rapid F420H2-dependent biotransformation within M. tuberculosis to afford intrabacterial nitric oxide and two amines, identified as JSF-3616 and JSF-3617. Thus, metabolism of JSF-2164 obscured the InhA inhibition phenotype within cultured M. tuberculosis. This study demonstrates a new docking/Bayesian computational strategy to combine cell- and target-based drug screening and the need to probe intrabacterial metabolism when clarifying the antitubercular mechanism of action.


Asunto(s)
Antituberculosos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/metabolismo , Oxadiazoles/farmacología , Oxidorreductasas/antagonistas & inhibidores , Aminas/metabolismo , Sitios de Unión , Ensayos Analíticos de Alto Rendimiento , Ligandos , Simulación del Acoplamiento Molecular , Óxido Nítrico/metabolismo , Oxadiazoles/química , Conformación Proteica
17.
BMC Infect Dis ; 19(1): 616, 2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-31299916

RESUMEN

BACKGROUND: The point mutations in 23S rRNA gene of Mycoplasma pneumoniae (M. pneumoniae) can lead to high-level resistance to macrolides. This study aimed to evaluate allele-specific real-time PCR (ASPCR) to detect the resistance-related mutations located at positions A2063G and A2064G of 23S rRNA gene. METHODS: We detected 178 pharyngeal swab specimens and calculated the proportions of resistant and sensitive quasispecies using ASPCR assays. ASPCR assays can detect down to 10 copies of 23S rRNA gene and achieved sensitivities of < 0.1% for A2063G and A2064G. We also compared the findings of ASPCR with the results of nested PCR with sequencing. RESULTS: Of 178 samples, 164 were found to have M. pneumoniae including 90.85% (149/164) samples with macrolide-resistant M. pneumoniae (MRMP) quasispecies by ASPCR, while 153 were found to be M. pneumoniae-positive including 71.90% (110/153) samples with MRMP quasispecies by nested PCR with sequencing. Of the 164 M. pneumoniae-positive samples, 61.59% (101/164) had the mixed population of wild-type and mutant M. pneumoniae, and 56.44% (57/101) of the latter contained the mutations at low frequency (≤50%). CONCLUSION: ASPCR indicated that sensitive and resistant quasispecies coexisted in most of the M. pneumoniae positive samples. The ASPCR was a highly sensitive, accurate and rapid method for detecting the macrolide resistance-associated mutations and it could provide earlier and more drug-resistant information for M. pneumoniae research and the clinical therapy.


Asunto(s)
Farmacorresistencia Bacteriana/genética , Mycoplasma pneumoniae/genética , Neumonía por Mycoplasma/diagnóstico , ARN Ribosómico 23S/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Antibacterianos/uso terapéutico , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , Femenino , Humanos , Macrólidos/uso terapéutico , Mycoplasma pneumoniae/aislamiento & purificación , Faringe/microbiología , Neumonía por Mycoplasma/tratamiento farmacológico , Neumonía por Mycoplasma/microbiología , Mutación Puntual , ARN Ribosómico 23S/genética , Reproducibilidad de los Resultados
18.
Medicine (Baltimore) ; 98(27): e16070, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31277102

RESUMEN

The aim of this study was to evaluate the inhibitory effect of antibiotics and Xiao'er Feire Kechuan Oral Solution on Mycoplasma pneumoniae (MP) clinical isolates.Twenty clinical isolates containing A-to-G transition at position 2063 and 10 clinical isolates without mutations in 23S rRNA V regions were randomly selected. The international standard strain FH was chosen as control strain. The minimum inhibitory concentration (MIC) of macrolide, quinolones, tetracycline, and Xiao'er Feire Kechuan Oral Solution to MP clinical isolates were performed using broth microdilution method.In vitro antibiotic susceptibility test of MP clinical isolates showed that MP showed high resistance to macrolide antibiotics (erythromycin and azithromycin); MIC of both were more than 64 µg/mL. The MICs of erythromycin and azithromycin for clinical isolates without mutations in 23S rRNA V regions were ≤0.5 µg/mL. The MICs of tetracycline and levofloxacin for all clinical isolated strains were ≤2.0 µg/mL and ≤1.0 µg/mL, respectively. The MIC of Xiao'er Feire Kechuan Oral Solution was 13.828∼6.914 mg/mL.In vitro, the drug resistance of MP to macrolide antibiotics is higher, MP clinical isolates are sensitive to tetracycline and levofloxacin, and Xiao'er Feire Kechuan Oral Solution also has a certain inhibitory effect on the macrolide-resistant MP.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Mycoplasma pneumoniae/efectos de los fármacos , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Humanos , Mycoplasma pneumoniae/aislamiento & purificación
19.
mBio ; 9(6)2018 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-30563908

RESUMEN

We report GSK3011724A (DG167) as a binary inhibitor of ß-ketoacyl-ACP synthase (KasA) in Mycobacterium tuberculosis Genetic and biochemical studies established KasA as the primary target. The X-ray crystal structure of the KasA-DG167 complex refined to 2.0-Å resolution revealed two interacting DG167 molecules occupying nonidentical sites in the substrate-binding channel of KasA. The binding affinities of KasA to DG167 and its analog, 5g, which binds only once in the substrate-binding channel, were determined, along with the KasA-5g X-ray crystal structure. DG167 strongly augmented the in vitro activity of isoniazid (INH), leading to synergistic lethality, and also synergized in an acute mouse model of M. tuberculosis infection. Synergistic lethality correlated with a unique transcriptional signature, including upregulation of oxidoreductases and downregulation of molecular chaperones. The lead structure-activity relationships (SAR), pharmacokinetic profile, and detailed interactions with the KasA protein that we describe may be applied to evolve a next-generation therapeutic strategy for tuberculosis (TB).IMPORTANCE Cell wall biosynthesis inhibitors have proven highly effective for treating tuberculosis (TB). We discovered and validated members of the indazole sulfonamide class of small molecules as inhibitors of Mycobacterium tuberculosis KasA-a key component for biosynthesis of the mycolic acid layer of the bacterium's cell wall and the same pathway as that inhibited by the first-line antitubercular drug isoniazid (INH). One lead compound, DG167, demonstrated synergistic lethality in combination with INH and a transcriptional pattern consistent with bactericidality and loss of persisters. Our results also detail a novel dual-binding mechanism for this compound as well as substantial structure-activity relationships (SAR) that may help in lead optimization activities. Together, these results suggest that KasA inhibition, specifically, that shown by the DG167 series, may be developed into a potent therapy that can synergize with existing antituberculars.


Asunto(s)
3-Oxoacil-(Proteína Transportadora de Acil) Sintasa/antagonistas & inhibidores , Antituberculosos/farmacología , Sinergismo Farmacológico , Isoniazida/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , 3-Oxoacil-(Proteína Transportadora de Acil) Sintasa/metabolismo , Animales , Antituberculosos/farmacocinética , Línea Celular , Cristalografía , Descubrimiento de Drogas , Femenino , Perfilación de la Expresión Génica , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Chaperonas Moleculares/genética , Mycobacterium tuberculosis/enzimología , Mycobacterium tuberculosis/genética , Oxidorreductasas/genética , Tuberculosis/tratamiento farmacológico
20.
Clin Lab ; 64(10): 1773-1776, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30336527

RESUMEN

BACKGROUND: Rhabditis (Rhabditellae) axei is a common species in soil, which has been reported repeatedly in human urine and the digestive system. Humans exposed to sewage or mistakenly polluted sewage is the cause of larvae infecting the digestive tract or via the urethra. We reported a patient infected with Rhabditis axei and Enterobius Vermicularis. The migration of the nematodes caused true signs of hematuria, diarrhea, and high eosinophilia. METHODS: Stool and urine are collected to detect parasite eggs and genotype. Specimens are sent for polymerase chain reaction (PCR)-based species identification. Amplification of the 18S ribosomal RNA gene was performed by PCR as described [1]. RESULTS: Morphological features and PCR amplification of the 18S ribosomal RNA gene confirmed Rhabditis axei and Enterobius vermicularis as the pathogen of infection. CONCLUSIONS: Herein, we presented a case that confirmed Rhabditis axei and Enterobius vermicularis infection in humans can be associated with high eosinophilia.


Asunto(s)
Enterobiasis/diagnóstico , Infecciones por Rhabditida/diagnóstico , Animales , Beijing , Preescolar , Diarrea/parasitología , Enterobiasis/parasitología , Enterobius/genética , Enterobius/fisiología , Eosinofilia/parasitología , Hematuria/parasitología , Humanos , Masculino , ARN Ribosómico 18S/genética , Infecciones por Rhabditida/parasitología , Rhabditoidea/genética , Rhabditoidea/fisiología
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