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1.
Mol Biol Rep ; 50(1): 121-132, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36315330

RESUMEN

BACKGROUND: Extrinsic molecular mechanisms that regulate hematopoietic stem/progenitor cell (HSPC) aging are still poorly understood, and a potential protective medication needs to be explored. MATERIALS AND METHODS: The senescent parameters of hematopoietic cells and bone marrow stromal cells (BMSCs) including cell cycle analysis, senescence-associated SA-ß-gal staining and signals, hematopoietic factors and cellular junction were analyzed in femur and tibia of rats. Furthermore, Sca-1+ HSPCs and BMSCs co-culture system was established to evaluate the direct effects of BMSC feeder layer to HSPCs. Oxidative DNA damage indicators in Sca-1+ HSCs and senescence-associated secretory phenotype (SASP) of BMSCs, gap junction intercellular communication between BMSCs, osteogenesis/adipogenisis differentiation balance of BMSCs were detected. RESULTS: In the D-gal pre-administrated rats, ASP treatment rescued senescence of hematopoietic cells and BMSCs, reserved CFU-GEMM; also, ASP treatment attenuated stromal oxidative load, ameliorated SCF, CXCL12, and GM-CSF production, increased Connexin-43 (Cx43) expression. BMSCs and Sca-1+ HSPCs co-cultivation demonstrated that ASP treatment prevented oxidative DNA damage response in co-cultured Sca-1+ HSPCs induced by D-gal pre-administration of feeder layer and the underlying mechanism may be related to ASP ameliorating feeder layer dysfunction due to D-gal induced senescence via inhibiting secretion of IL-1, IL-6, TNF-α, and RANTES, enhancing Cx43-mediated intercellular communication, improving Runx2 expression whereas decreasing PPARγ expression in BMSCs. CONCLUSION: The antioxidant property of ASP may provide a stroma-mediated potential therapeutic strategy for HSPC aging.


Asunto(s)
Angelica sinensis , Ratas , Animales , Galactosa , Conexina 43 , Senescencia Celular , Estrés Oxidativo , Envejecimiento , Polisacáridos/farmacología
2.
Microb Pathog ; 165: 105496, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35331848

RESUMEN

Staphylococcus aureus is a serious human pathogen that causes a wide variety of infectious diseases with high morbidity and mortality. Luteolin was recently shown to inhibit biofilm formation and reduce the production of virulence factors and the transcription of agrA in S. aureus. Given the broad impacts of the agr quorum-sensing system on the biofilm formation and virulence factors of S. aureus, this study aimed to investigate the effects of luteolin on the agr system and pathogenicity of S. aureus. Here, we show that at subminimal inhibitory concentrations (sub-MICs) that have no effect on bacterial growth, luteolin can markedly inhibit the adhesion and biofilm formation of both wild-type (WT) and agr mutant strains of S. aureus strain Newman. The hemolytic activity and toxin protein levels were markedly decreased in the culture supernatants of luteolin-treated WT strain but not the luteolin-treated agr mutant strain. qRT-PCR analysis showed that upon luteolin treatment, the expression of genes involved in virulence and biofilm formation was downregulated in the WT S. aureus strain, and the inefficacy of luteolin with respect to the virulence factors of only the agr mutant confirmed the agr-mediated antivirulence potential of luteolin. Furthermore, treatment with sub-MIC luteolin attenuated human alveolar epithelial A549 cell injury caused by the WT Newman strain and protected mice from pneumonia caused by the WT strain, but these effects were not observed with the agr mutant strain. These findings indicate that luteolin is a promising compound that interferes with the agr system and can be developed into novel therapeutic drugs against S. aureus infections.


Asunto(s)
Infecciones Estafilocócicas , Staphylococcus aureus , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Luteolina/farmacología , Ratones , Percepción de Quorum , Infecciones Estafilocócicas/microbiología , Transactivadores/genética , Transactivadores/metabolismo , Virulencia , Factores de Virulencia/genética , Factores de Virulencia/metabolismo
3.
Curr Microbiol ; 79(9): 271, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35881255

RESUMEN

Penicillin-binding proteins (PBPs) play an important role in bacterial biofilm formation and are the targets of ß-lactam antibiotics. This study aimed to investigate the effect of the ß-lactam antibiotic ceftazidime (CAZ) at subminimal inhibitory concentration (sub-MIC) on the biofilm formation of Escherichia coli by targeting PBPs. In this study, PBP1a (encoded by mrcA), PBP1b (encoded by mrcB) and PBP3 (encoded by ftsI), which have high affinity for CAZ, were deleted from the E. coli strain. The mrcB mutant showed lower adhesion, biofilm formation and swimming motility, whereas the knockout of mrcA or ftsI had no obvious influence on the biofilm-associated indicators mentioned above. After treatment with sub-MIC of CAZ, the adhesion, biofilm formation and swimming motility of the mrcB-mutant strain were not different or were slightly reduced compared with those of the untreated group. However, sub-MIC of CAZ still significantly inhibited these biofilm-associated indicators in mrcA- and ftsI-mutant strains. In addition, consistent with the bacterial motility results, the deletion of the mrcB gene reduced the flagellar numbers and the expression of flagellar structural genes, but flagellum-related indicators in the mrcB-mutant strain treated with CAZ were similar to those in the untreated group. Bioinformatic analysis showed that CAZ binds to Lys287, Lys274, Glu281, and Arg286 in PBP1b. Taken together, these results suggest that CAZ reduced flagellar synthesis and bacterial motility by binding with PBP1b and thereby inhibited the adhesion and biofilm formation of E. coli.


Asunto(s)
Infecciones por Escherichia coli , Proteínas de Escherichia coli , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Biopelículas , Ceftazidima/farmacología , Escherichia coli , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Humanos , Pruebas de Sensibilidad Microbiana , Proteínas de Unión a las Penicilinas/genética
4.
Biomed Chromatogr ; 36(12): e5501, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36082703

RESUMEN

Anlotinib is a novel small molecule multitarget tyrosine kinase inhibitor for the treatment of several cancers. We developed and validated a highly sensitive, rapid and stable high-performance liquid chromatography-mass spectrometrymethod for the determination of anlotinib in human plasma with anlotinib-d5 as a stable isotopically labeled internal standard (SIL-IS). To explore the feasibility of therapeutic drug monitoring in the treatment of tumors with anlotinib, human plasma samples were prepared by protein precipitation. The mobile phases comprised of (A) 5.0 mm NH4 AC aqueous solution containing 0.1% formic acid and (B) 100% methanol containing 0.1% formic acid. A gradient mobile phase system was adopted for chromatographic separation using a BEH C18 (2.1 × 50 mm, 1.7 µm) column. A positive ion pattern was chosen for quantification under multiple reaction monitoring mode. The ion pairs were detected at m/z 408.2 â†’ 339.1 and m/z 413.4 â†’ 344.3 for anlotinib and anlotinib-d5 (SIL-IS), respectively. The total run time was 5.0 min. The calibration curve was found to be linear within a plasma concentration range of 2-400 ng·ml-1 . The precision and accuracy, matrix effect, extraction recovery and stability were all validated and met the requirements of international guidelines. The proposed methods were successfully applied to support therapeutic drug monitoring in breast and thyroid cancer patients receiving anlotinib for therapy. Clinical data showed that in the 12 mg dose group, the mean plasma concentrations of anlotinib in breast cancer patients and thyroid cancer patients were 87.1 and 118.8 ng·ml-1 , respectively. The data demonstrate that the peak concentration of anlotinib may be related to the different tumor types in patients.


Asunto(s)
Espectrometría de Masas en Tándem , Neoplasias de la Tiroides , Humanos , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Monitoreo de Drogas , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los Resultados
5.
BMC Infect Dis ; 21(1): 141, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33535989

RESUMEN

BACKGROUND: The impact of COVID-19 has been devastating on a global scale. The negative conversion time (NCT) of SARS-CoV-2 RNA is closely related to clinical manifestation and disease progression in COVID-19 patients. Our study aimed to predict factors associated with prolonged NCT of SARS-CoV-2 RNA in mild/moderate COVID-19 patients. METHODS: The clinical features, laboratory data and treatment outcomes of COVID-19 patients were retrospectively analyzed. Then univariate and multivariate analysis were used to screen out risk factors of influencing prolonged NCT of SARS-CoV-2 RNA. RESULTS: Thirty-two hospitalized mild/moderate COVID-19 patients were enrolled. The general clinical symptoms were cough (78.1%), fever (75%), diarrhea (68.8%), expectoration (56.3%), and nausea (37.5%). More than 40% of the patients had decreased erythrocyte, hemoglobin and leucocyte and 93.8% patients were detected in abnormalities of chest CT. The median NCT of SARS-CoV-2 RNA was 19.5 days (IQR: 14.25-25). Univariate analysis found fever, nausea, diarrhea and abnormalities in chest CTs were positively associated with prolonged NCT of viral RNA (P< 0.05). The multivariate Cox proportional hazard model revealed that fever [Exp (B), 0.284; 95% CI, 0.114-0.707; P<0.05] and nausea [Exp (B), 0.257; 95%CI, 0.096-0.689; P<0.05] were two significant independent factors. CONCLUSIONS: Fever and nausea were two significant independent factors in prolonged NCT of viral RNA in mild/moderate COVID-19 patients, which provided a useful references for disease progression and treatment of COVID-19.


Asunto(s)
COVID-19/diagnóstico , ARN Viral/metabolismo , SARS-CoV-2/genética , Adulto , COVID-19/complicaciones , COVID-19/patología , COVID-19/virología , Prueba de Ácido Nucleico para COVID-19 , Tos/etiología , Diarrea/etiología , Femenino , Fiebre/etiología , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2/aislamiento & purificación , Índice de Severidad de la Enfermedad , Tórax/diagnóstico por imagen , Factores de Tiempo
6.
Mycoses ; 63(11): 1181-1190, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32416606

RESUMEN

BACKGROUND: Effects of CYP2C19 polymorphism on voriconazole concentration (C0 ), dose-adjusted trough concentrations (C0 /dose) and voriconazole-to-voriconazole-N-oxide concentration ratio (C0 /CN ) have not been fully investigated. OBJECTIVES: To investigate correlations of CYP2C19 polymorphisms with plasma concentrations of voriconazole and the major metabolite voriconazole-N-oxide in elderly patients. METHODS: A prospective, multi-centre, non-intervention, open clinical study was conducted within Southwestern Chinese patients clinically diagnosed with invasive fungal infections, to investigate the associations of CYP2C19∗2 (681G > A), CYP2C19∗3 (636G > A) and CYP2C19∗17 (-806C > T) genetic polymorphisms with voriconazole C0 , C0 /dose and C0 /CN . RESULTS: The study included 131 adult patients, of which 72 were elderly (≥60 years) and 59 were adults (<60 years). The allele frequencies of CYP2C19∗2, ∗3 and ∗17 in the elderly cohort were 61.1%, 29.9% and 7.6%, respectively, which were similar to those in the adult cohort (66.9%, 29.7% and 2.5%, respectively; P > .05). The median voriconazole C0 (C0 ), C0 /dose and C0 /CN ratio in patients with the CYP2C19∗1/∗2 and CYP2C19∗2/∗2 genotypes were significantly higher than those in patients with the CYP2C19∗1/∗1 genotype in the adult cohort (P < .05). The C0 and C0 /dose in patients with the CYP2C19∗1/∗3 and CYP2C19∗2/∗2 genotypes, and the C0 /CN ratio for patients with the CYP2C19∗1/∗2 genotype were numerically higher than those in patients with the CYP2C19∗1/∗1 genotype in the elderly cohort, but this difference was not statistically significant (P > 0.05). The C0 , C0 /dose and C0 /CN in patients with poor metaboliser phenotypes were higher than in those with normal metaboliser phenotypes and C0 in patients with intermediate metaboliser phenotypes were significantly higher than in those with normal metaboliser phenotypes in the adult cohort (P < .05). However, there were no significant differences in the C0 , C0 /dose and C0 /CN among different CYP2C19-predicted metabolic phenotypes in the elderly cohort. CONCLUSIONS: Voriconazole C0 , C0 /dose and C0 /CN ratio are not significantly affected by the CYP2C19∗2/∗3 polymorphisms in the elderly patients.

7.
Int J Mol Sci ; 18(11)2017 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-29143796

RESUMEN

Myelosuppression is the most common complication of chemotherapy. Decline of self-renewal capacity and stress-induced premature senescence (SIPS) of hematopoietic stem cells (HSCs) induced by chemotherapeutic agents may be the cause of long-term myelosuppression after chemotherapy. Whether the mechanism of SIPS of hematopoietic cells relates to chemotherapeutic injury occurred in hematopoietic microenvironment (HM) is still not well elucidated. This study explored the protective effect of Angelica sinensis polysaccharide (ASP), an acetone extract polysaccharide found as the major effective ingredients of a traditional Chinese medicinal herb named Chinese Angelica (Dong Quai), on oxidative damage of homo sapiens bone marrow/stroma cell line (HS-5) caused by 5-fluorouracil (5-FU), and the effect of ASP relieving oxidative stress in HM on SIPS of hematopoietic cells. Tumor-suppressive doses of 5-FU inhibited the growth of HS-5 in a dose-dependent and time-dependent manner. 5-FU induced HS-5 apoptosis and also accumulated cellular hallmarks of senescence including cell cycle arrest and typical senescence-associated ß-galactosidase positive staining. The intracellular reactive oxygen species (ROS) was increased in 5-FU treated HS-5 cells and coinstantaneous with attenuated antioxidant capacity marked by superoxide dismutase and glutathione peroxidase. Oxidative stress initiated DNA damage indicated by increased γH2AX and 8-OHdG. Oxidative damage of HS-5 cells resulted in declined hematopoietic stimulating factors including stem cell factor (SCF), stromal cell-derived factor (SDF), and granulocyte-macrophage colony-stimulating factor (GM-CSF), however, elevated inflammatory chemokines such as RANTES. In addition, gap junction channel protein expression and mediated intercellular communications were attenuated after 5-FU treatment. Significantly, co-culture on 5-FU treated HS-5 feeder layer resulted in less quantity of human umbilical cord blood-derived hematopoietic cells and CD34⁺ hematopoietic stem/progenitor cells (HSPCs), and SIPS of hematopoietic cells. However, it is noteworthy that ASP ameliorated SIPS of hematopoietic cells by the mechanism of protecting bone marrow stromal cells from chemotherapeutic injury via mitigating oxidative damage of stromal cells and improving their hematopoietic function. This study provides a new strategy to alleviate the complication of conventional cancer therapy using chemotherapeutic agents.


Asunto(s)
Angelica sinensis , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Polisacáridos/farmacología , Angelica sinensis/química , Angelica sinensis/metabolismo , Biomarcadores , Senescencia Celular/efectos de los fármacos , Daño del ADN , Fluorouracilo/farmacología , Humanos , Sustancias Protectoras , Especies Reactivas de Oxígeno/metabolismo
8.
Int J Clin Pharmacol Ther ; 54(5): 362-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27007995

RESUMEN

To develop a population-based pharmacokinetic model for the oral antiepileptic drug zonisamide using a cohort of healthy (nonepileptic) subjects and evaluate the effect of individual factors on the pharmacokinetics of zonisamide. 30 young adults (21-39 years) in good health were randomly assigned to 3 equal groups (1:1 sex ratio) for single-dose administration of zonisamide at 200 mg, 300 mg, or 400 mg. An additional 9 subjects (22-24 years) were administered once daily zonisamide at 300 mg for 14 days, and comprised the multiple dosing group. Venous blood samples were collected for analysis prior to (baseline, 0 hours) and after (1-300 hours) drug administration, providing 607 total samples used to build the pharmacokinetic model. The population pharmacokinetic analysis was performed by ICON's nonlinear mixed-effect modeling (NONMEM) software. Validation of the final model was carried out by nonparametric bootstrapping and visual predictive check. The zonisamide pharmacokinetics was best described by a two-compartment model with first-order elimination. In the final model, the estimated value of clearance (CL) was 23.25 L/h, the volume of distribution of the central compartment (Vc) was 34.50 L, the intercompartmental clearance (Q) was 20.22 L/h, and the Ka was 0.026 h(-1). The peripheral volume of distribution (Vp) was 1,429 L for single dose and 1,003 L for multiple doses. Body weight was the significant covariate affecting CL, Vc, Vp, and Q. Otherwise, female subjects had a lower Q than male subjects. The pharmacokinetics of zonisamide after oral administration could be described using a linear first-order elimination two-compartment model, which may provide a reference for clinical use of zonisamide in Chinese adults.


Asunto(s)
Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/farmacocinética , Pueblo Asiatico , Isoxazoles/administración & dosificación , Isoxazoles/farmacocinética , Modelos Biológicos , Administración Oral , Adulto , China , Esquema de Medicación , Femenino , Voluntarios Sanos , Humanos , Modelos Lineales , Masculino , Dinámicas no Lineales , Adulto Joven , Zonisamida
9.
Mol Biol Rep ; 41(4): 1901-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24595444

RESUMEN

Melatonin, a secretion from pineal gland is ambiguously considered as the key hormone involved in regulation of the antler cycle in Sika deer. To find out more about the roles of melatonin and its receptor gene, we carried out current study to investigate the association between polymorphisms in melatonin receptor 1A (MTNR1A) gene and the antler yield from Sika deer. A total of 251 Sika deer were analyzed in this study, of which consisted of Wusan Sika deer (n = 163) and Dongfeng Sika deer (n = 88). MTNRA gene was amplified by PCR and genotyped by Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Three polymorphism loci (C518T, C629G and C635T) were detected in exon2 of MTNR1A gene. The restriction site Ecol881 was used for C518T while a C629G polymorphism locus was digested with Mval restriction endonucleases. In Wusan Sika deer the allele frequencies of C and T were 0.637 and 0.363 for C518T, Also C and G alleles in C629G locus were 0.206 and 0.794. Genotypic frequencies of allele CC, CT and TT were 33.7, 59.9 and 6.4 % respectively, It showed 1.8, 37.4 and 60.7 % for frequencies of genotypes CC, CG and GG. In Dongfeng Sika deer the allele frequencies of C and T were 0.518 and 0.482 for C518T, C and G alleles were 0.375 and 0.625 for C629G. Genotypic frequencies were 10.6, 82.4 and 7.1 % for genotypes CC, CT and TT respectively, and they were 1.1, 72.7 and 26.2 % for genotypes CC, CG and GG. Among three SNPs, only C629G showed significant association (P < 0.05) with average antler yield in Wusan Sika deer, while no SNP was significant in Dongfeng Sika deer. These preliminary results implied that the identified SNPs of MTNR1A gene might influence the antler yield in Wusan Sika deer.


Asunto(s)
Cuernos de Venado/crecimiento & desarrollo , Ciervos/genética , Estudios de Asociación Genética , Polimorfismo de Nucleótido Simple , Receptores de Melatonina/genética , Alelos , Animales , Frecuencia de los Genes , Genotipo , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Sitios de Carácter Cuantitativo
10.
J Clin Pharmacol ; 64(4): 461-468, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37910022

RESUMEN

Hypokalemia and hyponatremia are common but easily ignored adverse events in treatment with voriconazole (VCZ) that can lead to serious consequences. We intend to investigate the incidence of VCZ-induced hypokalemia and hyponatremia and their risk factors based on real-world data. A prospective study was conducted. A total of 272 patients with 414 VCZ plasma trough concentrations (C0) and VCZ N-oxide concentrations (CN) were included. The incidence of hypokalemia was 18.0% (48/266). A total of 81.2% (39/48) of patients developed hypokalemia within 14 days, whereas 56.2% (27/48) of patients developed hypokalemia within 1 week. The proportion of female patients in the hypokalemia group was higher than that in the nonhypokalemia group, as was the proportion of patients receiving intravenous VCZ. In the multivariate analysis, the independent risk factors for hypokalemia were sex, combined use of antibiotics, and VCZ CN/C0. The incidence of hyponatremia was 7.9% (21/266). The proportion of patients over 47 years of age in the hyponatremia group was 71.4% (15/21). The number of days of VCZ use in the hyponatremia group was greater than that in the nonhyponatremia group. A total of 47.6% (10/21) of patients in the hyponatremia group had supratherapeutic VCZ C0 (>5.0 µg/mL). In conclusion, hypokalemia is more likely to occur in females, in patients receiving intravenous VCZ, and in patients with the combined use of antibiotics. Hyponatremia is more likely to occur in patients older than 47 years who have been using VCZ for a long time and have higher VCZ C0 values.


Asunto(s)
Hipopotasemia , Hiponatremia , Adulto , Humanos , Femenino , Voriconazol , Antifúngicos , Estudios Prospectivos , Monitoreo de Drogas , Hipopotasemia/tratamiento farmacológico , Estudios Retrospectivos , Antibacterianos/uso terapéutico
11.
J Glob Antimicrob Resist ; 33: 120-129, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36948495

RESUMEN

OBJECTIVE: Generic medications are widely used because of their low cost. However, some generic medications show lower quality and clinical efficacy compared with brand-name medications, especially for antimicrobial drugs. Levofloxacin is a fluoroquinolone antimicrobial drug with excellent antimicrobial activity and wide antimicrobial spectrum, while it is susceptible to drug resistance. Our study aims to evaluate the bioequivalence of generic and brand-name levofloxacin. METHODS: The pharmacokinetic (PK) parameters (Cmax, AUC0∼24, Tmax, and t1/2), pharmacodynamic (PD) parameters (in vitro antibacterial activity and the inhibition of resistant mutation), and PK/PD analysis (the probability of target attainment; the cumulative fraction of response) calculated by Monte Carlo simulation were investigated. RESULTS: Our results demonstrated that compared with generics, brand-name levofloxacin not only had higher drug content, it also showed higher antimicrobial susceptibility, higher resistance to mutation ability, and higher percentage of each dosage interval wherein plasma concentration of antimicrobial agents exceeded the MPC90 (mutant prevention concentration to prevent the mutation of 90% strains) against various clinical isolates. Although the differences in AUC0∼24 between brand-name levofloxacin and generics were not statistically significant (P > 0.05, F test), Monte Carlo simulation results showed cumulative fraction of response values for PK/PD of brand-name medications were higher than generics. CONCLUSION: Our results indicated that PK or PD equivalence did not imply therapeutic equivalence; thus, we suggest including PK/PD analysis in the bioequivalence evaluation system, which benefits prediction of clinical outcome with high application value.


Asunto(s)
Antiinfecciosos , Levofloxacino , Levofloxacino/farmacología , Método de Montecarlo , Antibacterianos , Fluoroquinolonas/farmacología
12.
Front Microbiol ; 14: 1153366, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37032905

RESUMEN

Introduction: Colistin is regarded as one of the last-resort antibiotics against severe infections caused by carbapenem-resistant Enterobacteriaceae. Strains with cooccurrence of mcr-9 and carbapenemase genes are of particular concern. This study aimed to investigate the genetic characteristics of a bla KPC-2-carrying plasmid, bla NDM-1-carrying plasmid and mcr-9-carrying plasmid coexisting in a carbapenem-resistant Enterobacter hormaechei isolate. Methods: E. hormaechei strain E1532 was subjected to whole-genome sequencing, and the complete nucleotide sequences of three resistance plasmids identified in the strain were compared with related plasmid sequences. The resistance phenotypes mediated by these plasmids were analyzed by plasmid transfer, carbapenemase activity and antimicrobial susceptibility testing. Results: Whole-genome sequencing revealed that strain E1532 carries three different resistance plasmids, pE1532-KPC, pE1532-NDM and pE1532-MCR. pE1532-KPC harboring bla KPC-2 and pE1532-NDM harboring bla NDM-1 are highly identical to the IncR plasmid pHN84KPC and IncX3 plasmid pNDM-HN380, respectively. The mcr-9-carrying plasmid pE1532-MCR possesses a backbone highly similar to that of the IncHI2 plasmids R478 and p505108-MDR, though their accessory modules differ. These three coexisting plasmids carry a large number of resistance genes and contribute to high resistance to almost all antibiotics tested, except for amikacin, trimethoprim/sulfamethoxazole, tigecycline and polymyxin B. Most of the plasmid-mediated resistance genes are located in or flanked by various mobile genetic elements, facilitating horizontal transfer of antibiotic resistance genes. Discussion: This is the first report of a single E. hormaechei isolate with coexistence of three resistance plasmids carrying mcr-9 and the two most common carbapenemase genes, bla KPC-2 and bla NDM-1. The prevalence and genetic features of these coexisting plasmids should be monitored to facilitate the establishment of effective strategies to control their further spread.

13.
Heliyon ; 9(11): e22015, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38045154

RESUMEN

Introduction: Voriconazole (VRZ) is the recommended standard treatment for life-threatening invasive aspergillosis. The plasma concentration of VRZ should be determined to optimise treatment results and reduce side effects. This study aimed to compare the correlation and concordance of ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and enzyme-multiplied immunoassay technique (EMIT) to determine VRZ plasma concentration in clinical practice. Methods: An isotopically labelled internal standard UPLC-MS/MS method was established, validated, and subsequently applied to determine VRZ concentration. The UPLC-MS/MS method was also compared with a commercial EMIT method regarding results correlation and concordance. Results: The calibration curve of UPLC-MS/MS was linear from 0.1 to 10 mg/L, the inter- and intra-day relative standard deviations (RSDs), and the stability of quality control samples were less than 15 %, satisfying the Bioanalytical Method Validation Guidelines. A total of 122 plasma samples were collected and analyzed using both methods. UPLC-MS/MS and EMIT showed a high correlation (r = 0.9534), and Bland-Altman analysis indicated a mean absolute bias of 1.035 mg/L and an average bias of 27.56 % between UPLC-MS/MS and EMIT. The paired Wilcoxon test and Bland-Altman analysis revealed poor consistency between the two methods. Furthermore, we compared the effects of different methods in clinical applications. Two threshold values for treatment efficacy (1.0 mg/L) and safety (5.5 mg/L) were established, and considerable discordance was observed between the original EMIT and UPLC-MS/MS results at both thresholds (p < 0.05). Nevertheless, the adjusted EMIT results were not inconsistent with the UPLC-MS/MS results regarding the efficacy (p = 0.125) and safety (p = 1.0) thresholds. Conclusions: The isotopically labelled internal standard UPLC-MS/MS method is established and well applied in the clinical setting. A strong correlation but discordance was found between UPLC-MS/MS and EMIT, indicating that switching from UPLC-MS/MS to EMIT was unsuitable. However, the adjusted EMIT results may serve as a reliable surrogate when UPLC-MS/MS results cannot be obtained when necessary.

14.
Front Physiol ; 14: 1138947, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36969583

RESUMEN

Background: The fruit of Terminalia chebula has been widely used for a thousand years for treating diarrhea, ulcers, and arthritic diseases in Asian countries. However, the active components of this Traditional Chinese medicine and their mechanisms remain unclear, necessitating further investigation. Objectives: To perform simultaneous quantitative analysis of five polyphenols in T. chebula and evaluate their anti-arthritic effects including antioxidant and anti-inflammatory activity in vitro. Materials and methods: Water, 50% water-ethanol, and pure ethanol were used as extract solvents. Quantitative analysis of gallic acid, corilagin, chebulanin, chebulagic acid, and ellagic acid in the three extracts was performed using high-performance liquid chromatography (HPLC). Antioxidant activity was assessed by the 2,2-diphenylpicrylhydrazyl (DPPH) radical-scavenging assay, and anti-inflammatory activity was evaluated by detecting interleukin (IL)-6 and IL-8 expression in IL-1ß-stimulated MH7A cells. Results: The 50% water-ethanol solvent was the optimal solvent yielding the highest total polyphenol content, and the concentrations of chebulanin and chebulagic acid were much higher than those of gallic acid, corilagin, and ellagic acid in the extracts. The DPPH radical-scavenging assay showed that gallic acid and ellagic acid were the strongest antioxidative components, while the other three components showed comparable antioxidative activity. As for the anti-inflammatory effect, chebulanin and chebulagic acid significantly inhibited IL-6 and IL-8 expression at all three concentrations; corilagin and ellagic acid significantly inhibited IL-6 and IL-8 expression at high concentration; and gallic acid could not inhibit IL-8 expression and showed weak inhibition of IL-6 expression in IL-1ß-stimulated MH7A cells. Principal component analysis indicated that chebulanin and chebulagic acid were the main components responsible for the anti-arthritic effects of T. chebula. Conclusion: Our findings highlight the potential anti-arthritic role of chebulanin and chebulagic acid from T. chebula.

15.
Acta Trop ; 228: 106326, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35077675

RESUMEN

OBJECTIVE: To investigate a detailed genomic characterization of the blaIMP-10-carrying plasmid p12NE515 from a Pseudomonas aeruginosa isolate in China. METHODS: Plasmid p12NE515 was subjected to whole-genome sequencing and the complete sequence was compared with related plasmid sequences. Transferability of plasmid, carbapenemase activity and bacterial susceptibility profiles were determined to assess p12NE515-mediated resistance phenotypes. RESULTS: P. aeruginosa 12NE515 was identified as a less common sequence type of ST1976. p12NE515 harboring blaIMP-10 possessed a backbone identical to plasmid p60512-IMP (carrying blaIMP-1), but the accessory resistance regions differed. Only one accessory module, Tn7339, was carried in p12NE515, and this transposon was an insertion sequence-mediated transposition unit generated by the insertion of a novel class 1 integron, In1814, at the downstream end of ISPa17. Here, blaIMP-10 together with aacA7 was located in In1814, being at evolution stage III of Tn402-associated integron due to truncation of the tni module. CONCLUSION: This study is the first to determine the complete sequence of a blaIMP-10-carrying plasmid, and this is also the first report of a blaIMP-10-producing strain in China. The prevalence of the blaIMP-10 gene and the genetic characterization of the blaIMP-10-carrying plasmid should be analyzed to provide deeper insight into the transmission mechanism of antimicrobial resistance genes.


Asunto(s)
Pseudomonas aeruginosa , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Pruebas de Sensibilidad Microbiana , Plásmidos/genética
16.
Front Pharmacol ; 13: 835871, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35462904

RESUMEN

Background: The inner association of inflammation with voriconazole (VCZ) metabolism has not been fully investigated. We intend to investigate the effects of inflammation on liver function, VCZ trough concentration (C0), C0/dose ratio and the ratio of VCZ to VCZ-N-oxide concentration (C0/CN) in adult and elderly patients. Methods: A single-center retrospective study was conducted among patients who were treated in our hospital between January 2018 and December 2021. For each eligible patient, demographic details, medical history, laboratory parameters, procalcitonin (PCT), C reactive protein (CRP), and interleukin-6 (IL-6) were collected from the medical chart. VCZ CN, TNF-α, IL-1ß, IL-8, and IL-10 concentrations were detected in blood samples. Results: A total of 356 patients were included in our study, with 195 patients in the adult cohort (<60 years) and 161 patients in the elderly cohort (≥60 years). In adult patients, CRP and IL-8 levels showed moderate association with VCZ C0/CN ratio (CRP: r = 0.512, p < 0.001; IL-8: r = 0.476, p = 0.002). IL-6 level shallowly associated with VCZ C0/CN ratio both in adult and elderly patients (r = 0.355, p = 0.003; r = 0.386, p = 0.001). A significantly higher VCZ C0, C0/dose ratio and C0/CN ratio was observed in adult patients with severe inflammation compared with patients with moderate inflammation and no to mild inflammation, as reflected by PCT levels (p < 0.05). However, there was no significant difference observed among different inflammation degrees in elderly patients. Lower albumin (AL) and higher total bilirubin (TBIL) were observed along with the degree of inflammation in both adult and elderly patients, as reflected by CRP and PCT levels (p < 0.05). Conclusion: Inflammation may affect the metabolism of VCZ to VCZ-N-oxide both in adult and elderly patients, and decreased plasma AL levels and increased TBIL levels under inflammatory conditions may also alter VCZ metabolism.

17.
Antimicrob Agents Chemother ; 54(6): 2707-11, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20231401

RESUMEN

Biofilm formation in Staphylococcus epidermidis is mediated by icaADBC-dependent and -independent pathways. Subinhibitory concentrations of erythromycin, azithromycin, and clarithromycin enhanced, in a dose-dependent manner, the level of biofilm formation by 20% (21/105 isolates) by macrolide-resistant ica-positive and -negative isolates tested in vitro. The presence of ica, however, apparently produced an enhanced effect on biofilm formation. The levels of expression of the biofilm-related genes icaA, atlE, fruA, pyrR, sarA, and sigB were increased in response to erythromycin. The results likely underscore the potential clinical relevance of macrolide-induced biofilm growth.


Asunto(s)
Antibacterianos/administración & dosificación , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Genes Bacterianos , Macrólidos/administración & dosificación , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus epidermidis/genética , Secuencia de Bases , Cartilla de ADN/genética , Relación Dosis-Respuesta a Droga , Eritromicina/administración & dosificación , Expresión Génica/efectos de los fármacos , Humanos , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Staphylococcus epidermidis/aislamiento & purificación , Staphylococcus epidermidis/fisiología
18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 25(4): 1178-1186, 2017 Aug.
Artículo en Zh | MEDLINE | ID: mdl-28823289

RESUMEN

OBJECTIVE: To investigate the damage effect of 5-fluorouracil(5-FU) with tumor inhibition concentration on human bone marrow mesenchymal stem cells (hBMSC) and influence of its effect on the hematopoietic cells. METHODS: The Cell Counting Kit-8 was used for determining the sensitivity of breast cancer cell line MCF-7, colon cancer cell line HCT-116 and HS-5 derived from human bone marrow stronal cell line to the different doses of 5-fluorouracil in vitro. After HS-5 was treated with 5-fluorouracil, crystal violet staining assay was used to count the number of colony forming unit-fibroblast, the distribution of cell cycle was analyzed by flow cytometry (FCM), apoptosis was assessed by Annexin V/PI double-stained method and Hoechest staining; DCFH-DA staining was used to analyse the level of reactive oxygen species (ROS), ELISA and immuofluorescence were used to detect cytokines KL, GM-CSF, RANTS and SDF. The hUCB-MNC was counted by trypan blue staining after co-culture with HS-5, FCM was used to detect the cell cycle distribution, ROS level and the ratio of CD34+ cells. The levels of glutathione peroxidase (GSH-Px) and total superoxide dismutase(T-SOD) were measured by enzymatic assay. The senescence associated-ß-galactosidase (SA-ß-Gal) staining was used to detect the senescent hUCB-MNC. RESULTS: 5-Fluorouracil of 12.5 µg/ml-100 µg/ml inhibited the proliferation of MCF-7, HCT-116 and HS-5 cells in dose-dependent and time-dependent manner, among them HS-5 was more sensitive to 5- fluorouracil. After treatment with 5-fluorouracil, the HS-5 cell cycle was blocked. The apoptosis rate and the intracellular ROS level of HS-5 significantly increased. Also HS-5-secreted hematopoietic growth factors decreased and inflammatory chemokines increased. After co-cultured with 5-fluorouracil-treated HS-5, the number of hUCB-MNC and the ratio of CD34+ cells were decreased. hUCB-MNC cell cycle blocked in G1 phase. The antioxidant capacity also decreased and the intracellular ROS level increased significantly. The senescent hUCB-MNC increased. CONCLUSION: 5-Fluorouracil can result in oxidative damage of bone marrow stromal cells and change of function secreting bioactivators, thus induce oxidative stress in hematopoietic cells to initiate stress-induced premature senescence (SIPS).


Asunto(s)
Células Madre Mesenquimatosas , Células de la Médula Ósea , Senescencia Celular , Fluorouracilo , Trasplante de Células Madre Hematopoyéticas , Humanos
19.
J Microbiol Immunol Infect ; 49(1): 33-40, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24768213

RESUMEN

BACKGROUND/PURPOSE: Subminimal inhibitory concentration (sub-MIC) of antibiotics can modify the phenotype of biofilm formation in bacteria. However, the relationship between resistance phenotypes, genotypes, and the biofilm formation phenotype in response to sub-MIC antibiotics remains unclear. METHODS: Here, we collected 96 clinical isolates of Staphylococcus epidermidis (S. epidermidis) and investigated the erythromycin (ERY) susceptibility, the biofilm formation in respond to sub-MIC ERY, the presence and transcription expression of erm genes. Serial passage of induction resistance was used against ERY-susceptible isolates and biofilm formation in response to their new sub-MIC ERY was determined. RESULTS: The incidence of biofilm phenotype modification in ERY-resistant isolates was significantly higher than that of ERY-susceptible isolates [27/85 (31.8%) vs. 0/11 (0%), p = 0.031]. Yet, ERY-susceptible isolates displayed the phenomenon of biofilm phenotype modification (7/11), after induction of resistance to ERY. The ermC gene was absolutely dominant among the three macrolide resistant genes including erm (A, B, C) [6/96 (6.2%), 6/96 (6.2%), and 91/96 (94.8%), respectively]. With statistic stratification analysis, a linear and positive correlation was identified between the two factors in the biofilm-enhanced strains, a linear and negative correlation in biofilm-inhibited strains, and a weakly positive correlation in biofilm-unaffected strains (R(2) = 0.4992, 0.3686, and 0.0512, respectively). CONCLUSION: The results suggest that the ERY resistance phenotype and the transcription expression of ermC gene could be considered as important signs to estimate whether the biofilm formation phenotype in S. epidermidis clinical isolates can be easily affected by sub-MIC ERY.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Farmacorresistencia Bacteriana , Eritromicina/farmacología , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus epidermidis/fisiología , Perfilación de la Expresión Génica , Genes Bacterianos , Humanos , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/aislamiento & purificación , ARNt Metiltransferasas/genética
20.
Zhonghua Shao Shang Za Zhi ; 31(4): 285-9, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26715638

RESUMEN

OBJECTIVE: To study the effects of inhibitory peptide of Staphylococcus epidermidis (SE) biofilm (briefly referred to as inhibitory peptide) on adhesion and biofilm formation of SE at early stage. METHODS: By using peptide synthesizer, the inhibitory peptide was synthesized with purity of 96.8% and relative molecular mass of 874.4. (1) Solution of SE ATCC 35984 (the same below) was cultivated with inhibitory peptide in the final concentrations of 1-256 µg/mL, and the M-H broth without bacteria solution was used as blank control. The MIC of the inhibitory peptide against SE was determined (n=3). (2) Solution of SE was cultivated with trypticase soy broth (TSB) culture solution containing inhibitory peptide in the final concentrations of 16, 32, 64, 128, and 256 µg/mL (set as inhibitory peptide groups in corresponding concentration), and solution of SE being cultivated with TSB culture medium was used as negative control group. Growth of SE was observed every one hour from immediately after cultivation (denoted as absorbance value), and the growth curve of SE during the 24 hours of cultivation was drawn, with 3 samples in each group at each time point. (3) Solution of SE was cultivated with TSB culture solution containing inhibitory peptide in the final concentrations of 16, 32, 64, 128, and 256 µg/mL (set as inhibitory peptide groups in corresponding concentration), and solution of SE being cultivated with TSB culture medium was used as negative control group. Adhesive property of SE was observed after cultivation for 4 hours (denoted as absorbance value, n=10); biofilm formation of SE was observed after cultivation for 20 hours (denoted as absorbance value, n=10). (4) Solution of SE was cultivated with TSB culture solution containing inhibitory peptide in the final concentration of 128 µg/mL (set as 128 µg/mL inhibitory peptide group), and solution of SE being cultivated with TSB culture medium was used as negative control group. Adhesive property of SE and its biofilm formation were observed with confocal laser scanning microscope (CLSM), and the sample numbers were both 3. Data were processed with one-way analysis of variance, LSD test, and Dunnett T3 test. RESULTS: (1) The MIC of inhibitory peptide against SE exceeded 256 µg/mL. (2) There was no significant difference in the growth curve of SE between inhibitory peptide groups in different concentrations and negative control group. (3) After 4 hours of cultivation, the absorbance values of adhesive property of SE in 256, 128, 64, and 32 µg/mL inhibitory peptide groups were respectively 0.20 ± 0.04, 0.27 ± 0.03, 0.35 ± 0.04, and 0.40 ± 0.04, which were significantly lower than the absorbance value in negative control group (0.53 ± 0.10, P<0.05 or P<0.01); the absorbance value of adhesive property of SE in 16 µg/mL inhibitory peptide group was 0.47 ± 0.09, which was close to the absorbance value in negative control group (P>0.05). After 20 hours of cultivation, the absorbance values of biofilm formation of SE in 256, 128, and 64 µg/mL inhibitory peptide groups were respectively 0.49 ± 0.10, 0.68 ± 0.06, and 0.93 ± 0.13, which were significantly less than the absorbance value in negative control group (1.21 ± 0.18, P<0.05 or P<0.01); the absorbance values of biofilm formation in 32 and 16 µg/mL inhibitory peptide groups were respectively 1.18 ± 0.22 and 1.15 ± 0.26, which were close to the absorbance value in negative control group (with P values above 0.05). (4) CLSM showed that more adhering bacteria and compact structure of biofilm were observed in negative control group, but less adhering bacteria and loose structure of biofilm were observed in 128 µg/mL inhibitory peptide group. CONCLUSIONS: The inhibitory peptide can inhibit adhesion and biofilm formation of SE at early stage, but its structure still needs to be further modified.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Péptidos , Staphylococcus epidermidis/fisiología , Adhesión Bacteriana , Humanos , Microscopía Confocal , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/metabolismo
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