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1.
Int Microbiol ; 27(2): 349-359, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37410300

RESUMEN

Nitric oxide (NO), produced through the denitrification pathway, regulates biofilm dynamics through the quorum sensing system in Pseudomonas aeruginosa. NO stimulates P. aeruginosa biofilm dispersal by enhancing phosphodiesterase activity to decrease cyclic di-GMP levels. In a chronic skin wound model containing a mature biofilm, the gene expression of nirS, encoding nitrite reductase to produce NO, was low, leading to reduced intracellular NO levels. Although low-dose NO induces biofilm dispersion, it is unknown whether it influences the formation of P. aeruginosa biofilms in chronic skin wounds. In this study, a P. aeruginosa PAO1 strain with overexpressed nirS was established to investigate NO effects on P. aeruginosa biofilm formation in an ex vivo chronic skin wound model and unravel the underlying molecular mechanisms. Elevated intracellular NO levels altered the biofilm structure in the wound model by inhibiting the expression of quorum sensing-related genes, which was different from an in vitro model. In Caenorhabditis elegans as a slow-killing infection model, elevated intracellular NO levels increased worms' lifespan by 18%. Worms that fed on the nirS-overexpressed PAO1 strain for 4 h had complete tissue, whereas worms that fed on empty plasmid-containing PAO1 had biofilms on their body, causing severe damage to the head and tail. Thus, elevated intracellular NO levels can inhibit P. aeruginosa biofilm growth in chronic skin wounds and reduce pathogenicity to the host. Targeting NO is a potential approach to control biofilm growth in chronic skin wounds wherein P. aeruginosa biofilms are a persistent problem.


Asunto(s)
Infecciones por Pseudomonas , Pseudomonas aeruginosa , Animales , Pseudomonas aeruginosa/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico/farmacología , Biopelículas , Percepción de Quorum , Virulencia , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/microbiología
2.
Inorg Chem ; 63(9): 4269-4278, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38373873

RESUMEN

High-purity heavy water (D2O) is a strategic material owing to its important application in the fields of nuclear energy and scientific research. D2O always tends to get contaminated by H2O owing to its strong hygroscopicity. Herein, a bimetallic hexanuclear Ln(III) cluster-based metal-organic framework (Eu0.5Tb0.5-TZB-MOF) has been synthesized for fluorescence sensing of the D2O-H2O binary mixtures. Eu0.5Tb0.5-TZB-MOF can be used to immediately differentiate D2O or H2O via fluorescent color responses that are obvious to the naked eye and allow for quantitative ratiometric analysis using simple spectrophotometry. Fluorescence titration experiments demonstrate that both trace H2O in D2O and trace D2O in H2O can be quantitatively detected. Mechanistic studies demonstrate that the weaker vibrational quenching of the O-D oscillator compared to the O-H oscillator, in addition to the terbium-to-europium energy transfer, triggered the fluorescence signal response.

3.
BMC Genomics ; 24(1): 332, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37322453

RESUMEN

The rich genetic diversity in Citrullus lanatus and the other six species in the Citrullus genus provides important sources in watermelon breeding. Here, we present the Citrullus genus pan-genome based on the 400 Citrullus genus resequencing data, showing that 477 Mb contigs and 6249 protein-coding genes were absent in the Citrullus lanatus reference genome. In the Citrullus genus pan-genome, there are a total of 8795 (30.5%) genes that exhibit presence/absence variations (PAVs). Presence/absence variation (PAV) analysis showed that a lot of gene PAV were selected during the domestication and improvement, such as 53 favorable genes and 40 unfavorable genes were identified during the C. mucosospermus to C. lanatus landrace domestication. We also identified 661 resistance gene analogs (RGAs) in the Citrullus genus pan-genome, which contains 90 RGAs (89 variable and 1 core gene) located on the pangenome additional contigs. By gene PAV-based GWAS, 8 gene presence/absence variations were found associated with flesh color. Finally, based on the results of gene PAV selection analysis between watermelon populations with different fruit colors, we identified four non-reference candidate genes associated with carotenoid accumulation, which had a significantly higher frequency in the white flesh. These results will provide an important source for watermelon breeding.


Asunto(s)
Citrullus , Citrullus/genética , Domesticación , Fitomejoramiento , Genoma de Planta , Análisis de Secuencia de ADN
4.
Appl Microbiol Biotechnol ; 105(1): 341-352, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33215259

RESUMEN

Phomopsis liquidambari S47 is an endophytic fungus isolated from the leaves of Punica granatum. Here, we are the first to report a quorum sensing (QS) inhibitor 1-(4-amino-2-hydroxyphenyl)ethanone (AHE) isolated and identified from the metabolites of P. liquidambari S47. Exposure to AHE at sub-MIC concentrations notably suppressed the secretion of acyl-homoserine lactones and virulence factors in Pseudomonas aeruginosa PAO1. To investigate the metabolic variations of P. aeruginosa PAO1 exposed to AHE, magnetic resonance imaging-based metabolomic analysis was performed. AHE treatment created a disturbance in the QS system by suppressing the expressions of QS-related genes. The disturbed QS system resulted in the inhibited activity of antioxidant enzymes and thus enhanced oxidative stress. The vegetable infection assay showed that the virulence of P. aeroginosa PAO1 was attenuated which could be due to the impacts to the amino acid and nucleotide metabolism by enhanced oxidative stress. These findings suggest that AHE has a potential to become an antivirulence "agent" to tackle P. aeruginosa infection. KEY POINTS: • AHE treatment inhibited AHL secretion and virulence factors production. • AHE treatment aggravated oxidative stress and disturbed metabolism. • AHE suppressed QS-related gene expressions and reduced virulence of P. aeruginosa.


Asunto(s)
Antibiosis , Phomopsis , Pseudomonas aeruginosa , Percepción de Quorum , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/farmacología , Biopelículas , Virulencia , Factores de Virulencia/genética
5.
Artículo en Inglés | MEDLINE | ID: mdl-32229494

RESUMEN

KBP-7072 is a semisynthetic aminomethylcycline with broad-spectrum activity against Gram-positive and Gram-negative pathogens, including multidrug-resistant bacterial strains. The pharmacokinetics (PK) of KBP-7072 after oral and intravenous (i.v.) administrations of single and multiple doses were investigated in animal models, including during fed and fasted states, and the protein binding and excretion characteristics were also evaluated. In Sprague-Dawley (SD) rats, beagle dogs, and CD-1 mice, KBP-7072 demonstrated a linear PK profile after the administration of single oral and i.v. and multiple oral doses. The oral bioavailability ranged from 12% to 32%. The mean time to maximum concentration (Tmax) ranged from 0.5 to 4 h, and the mean half-life ranged from approximately 6 to 11 h. The administration of oral doses in the fed state resulted in marked reductions in the maximum plasma concentration (Cmax) and the area under the concentration-time curve (AUC) compared with dosing in fasted animals. The mean bound fractions of KBP-7072 were 77.5%, 69.8%, 64.5%, 69.3%, and 69.2% in mouse, rat, dog, monkey, and human plasma, respectively. Following a single 22.5-mg/kg oral dose of KBP-7072 in SD rats, the cumulative excretion in feces was 64% and that in urine was 2.5% of the administered dose. The PK results in animal models are consistent with single- and multiple-ascending-dose studies in healthy volunteers and confirm the suitability of KBP-7072 for once-daily oral and i.v. administration in clinical studies.


Asunto(s)
Antibacterianos , Administración Oral , Animales , Área Bajo la Curva , Perros , Semivida , Ratones , Modelos Animales , Unión Proteica , Ratas , Ratas Sprague-Dawley
6.
Artículo en Inglés | MEDLINE | ID: mdl-32071042

RESUMEN

KBP-7072 is a novel third-generation tetracycline (aminomethylcycline) antibacterial that overcomes common efflux and ribosomal protection resistance mechanisms that cause resistance in older-generation tetracyclines. KBP-7072 completed phase 1 clinical development studies for safety, tolerability, and pharmacokinetics (ClinicalTrials.gov identifier NCT02454361) and multiple ascending doses in healthy subjects (ClinicalTrials.gov identifier NCT02654626) in December 2015. Both oral and intravenous formulations of KBP-7072 are being developed. In this study, we evaluated the in vitro activities of KBP-7072 and comparator agents by CLSI document M07 (2018) broth microdilution against 531 recent geographically diverse and/or molecularly characterized Acinetobacter baumannii-A. calcoaceticus species complex (A. baumannii) isolates from the United States, Europe, Asia-Pacific (excluding China), and Latin America. A. baumannii isolates included carbapenem-resistant, colistin-resistant, tetracycline-resistant, and extended-spectrum-ß-lactamase (ESBL)- and metallo-ß-lactamase (MBL)-producing isolates. Overall, KBP-7072 (MIC50/90, 0.25/1 mg/liter) was comparable in activity to colistin (92.8%/92.8% susceptible [S] [CLSI/EUCAST]) against A. baumannii isolates, inhibiting 99.2% of isolates at ≤2 mg/liter and 97.6% of isolates at ≤1 mg/liter. KBP-7072 was equally active against A. baumannii isolates, including carbapenem-resistant, colistin-resistant, and tetracycline-resistant isolates, regardless of geographic location, and maintained activity against ESBL- and MBL-producing isolates. KBP-7072 outperformed comparator agents, including ceftazidime (40.3% S [CLSI]), gentamicin (48.2%/48.2% S [CLSI/EUCAST]), levofloxacin (39.5%/37.9% S [CLSI/EUCAST]), meropenem (42.0%/42.0% S [CLSI/EUCAST]), piperacillin-tazobactam (33.3% S [CLSI]), and all tetracycline-class comparator agents, which include doxycycline (67.3% S [CLSI]), minocycline (73.8% S [CLSI]), tetracycline (37.2% S [CLSI]), and tigecycline (79.5% inhibited by ≤2 mg/liter). The potent in vitro activity of KBP-7072 against recent geographically diverse, molecularly characterized, and drug-resistant A. baumannii isolates supports continued clinical development for the treatment of serious infections, including those caused by A. baumannii.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/farmacología , Tetraciclinas/farmacología , Acinetobacter baumannii/enzimología , Acinetobacter baumannii/genética , Carbapenémicos/farmacología , Colistina/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Resistencia a la Tetraciclina/efectos de los fármacos , beta-Lactamasas/metabolismo
7.
Endocr Pract ; 26(8): 900-908, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33471681

RESUMEN

OBJECTIVE: Moderate-to-severe subacute thyroiditis is clinically managed with 6 to 8 weeks of glucocorticoid therapy. However, no studies have evaluated short-term prednisone treatment for subacute thyroiditis. METHODS: This 24-week, prospective, single-blind, randomized controlled study enrolled patients (aged 18 to 70 years) with subacute thyroiditis who were hospitalized between August, 2013, and December, 2014. Patients with moderate-to-severe symptoms were randomly assigned to receive either 30 mg/day prednisone for 1 week, followed by 1 week of nonsteroidal anti-inflammatory drugs, or the conventional 6-week prednisone therapy. The primary endpoint was intergroup differences in treatment efficacy at the end of the treatment course. Secondary endpoints included between-group differences in post-withdrawal adverse effect parameters and thyroid function at weeks 6, 12, and 24. RESULTS: We screened 96 patients, randomized 52 participants, and 50 participants completed the study. Efficacy and recurrence rates were not significantly different at withdrawal in both groups (P = .65). At treatment discontinuation, parathyroid hormone (28.8 versus 38.9 pg/mL; P = .011) and systolic blood pressure (113.9 versus 122.4mm Hg; P = .023) were significantly lower in the experimental group than in the control group. There were no significant intergroup differences in other secondary endpoints at withdrawal and in thyroid function at weeks 6, 12, and 24. CONCLUSION: Fewer side effects of glucocorticoids and similar efficacy and recurrence rates were observed with short-term prednisone compared with the 6-week treatment for subacute thyroiditis. Short-term prednisone, with a better safety profile, may be an alternative strategy for ameliorating moderate-to-severe symptoms of subacute thyroiditis. ABBREVIATIONS: BPPG = breakfast postprandial plasma glucose; CRP = C-reactive protein; ESR = erythrocyte sedimentation rate; FPG = fasting plasma glucose; FT3 = free triiodothyronine; FT4 = free thyroxine; GA = glycated albumin; NSAIDs = nonsteroidal anti-inflammatory drugs; OC = osteocalcin; PINP = type I procollagen amino-terminal peptide; PTH = parathyroid hormone; RCT = randomized controlled trial; SAT = subacute thyroiditis; SBP = systolic blood pressure; TC = total cholesterol; TSH = thyroid-stimulating hormone; TBG = thyroid-binding globulin; TG = triglyceride; TGAb = antithyroglobulin antibody; TPOAb = antithyroid peroxidase antibody; TRAb = antithyroid-stimulating hormone receptor antibody.


Asunto(s)
Tiroiditis Subaguda , Adolescente , Adulto , Anciano , Glucocorticoides/uso terapéutico , Humanos , Persona de Mediana Edad , Prednisona/efectos adversos , Estudios Prospectivos , Método Simple Ciego , Tiroiditis Subaguda/tratamiento farmacológico , Tiroxina , Triyodotironina , Adulto Joven
8.
Nitric Oxide ; 90: 1-9, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31170453

RESUMEN

Currently, most antimicrobial topical treatments utilize antibiotics to prevent or treat infection at a wound site. However, with the ongoing evolution of multi-drug resistant bacterial strains, there is a high demand for alternative antimicrobial treatments. Nitric oxide (NO) is an endogenous gas molecule with potent antimicrobial activity, which is effective against a wide variety of bacterial strains. In this study, the potential for creating NO releasing creams containing the naturally occurring NO carrier, S-nitrosoglutathione (GSNO), are characterized and evaluated. GSNO is shown to have prolonged stability (>300 days) when mixed and stored within Vaseline at 24 °C. Further, enhanced proliferation of NO from GSNO using zinc oxide nanoparticles (ZnO) is demonstrated. Triggering NO release from the GSNO/Vaseline mixture using a commercial zinc oxide-containing cream exhibits first-order NO release kinetics with the highest %NO release over the first 6 h. Significant killing effects against S. aureus, S. epidermidis, and P. aeruginosa are demonstrated for the GSNO/Vaseline/ZnO cream mixtures in a proportional manner dependent upon the concentration of GSNO in the final mixture.


Asunto(s)
Antibacterianos/farmacología , Óxido Nítrico/metabolismo , S-Nitrosoglutatión/farmacología , Óxido de Zinc/farmacología , Antibacterianos/química , Antibacterianos/metabolismo , Pruebas de Sensibilidad Microbiana , Óxido Nítrico/química , Pseudomonas aeruginosa/efectos de los fármacos , S-Nitrosoglutatión/química , S-Nitrosoglutatión/metabolismo , Staphylococcus aureus/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos , Óxido de Zinc/química , Óxido de Zinc/metabolismo
9.
N Engl J Med ; 370(9): 818-28, 2014 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-24571754

RESUMEN

BACKGROUND: Enterovirus 71 (EV71) is one of the major causative agents of outbreaks of hand, foot, and mouth disease or herpangina worldwide. This phase 3 trial was designed to evaluate the efficacy, safety, and immunogenicity of an EV71 vaccine. METHODS: We conducted a randomized, double-blind, placebo-controlled, multicenter trial in which 10,007 healthy infants and young children (6 to 35 months of age) were randomly assigned in a 1:1 ratio to receive two intramuscular doses of either EV71 vaccine or placebo, 28 days apart. The surveillance period was 12 months. The primary end point was the occurrence of EV71-associated hand, foot, and mouth disease or herpangina. RESULTS: During the 12-month surveillance period, EV71-associated disease was identified in 0.3% of vaccine recipients (13 of 5041 children) and 2.1% of placebo recipients (106 of 5028 children) in the intention-to-treat cohort. The vaccine efficacy against EV71-associated hand, foot, and mouth disease or herpangina was 94.8% (95% confidence interval [CI], 87.2 to 97.9; P<0.001) in this cohort. Vaccine efficacies against EV71-associated hospitalization (0 cases vs. 24 cases) and hand, foot, and mouth disease with neurologic complications (0 cases vs. 8 cases) were both 100% (95% CI, 83.7 to 100 and 42.6 to 100, respectively). Serious adverse events occurred in 111 of 5044 children in the vaccine group (2.2%) and 131 of 5033 children in the placebo group (2.6%). In the immunogenicity subgroup (1291 children), an anti-EV71 immune response was elicited by the two-dose vaccine series in 98.8% of participants at day 56. An anti-EV71 neutralizing antibody titer of 1:16 was associated with protection against EV71-associated hand, foot, and mouth disease or herpangina. CONCLUSIONS: The EV71 vaccine provided protection against EV71-associated hand, foot, and mouth disease or herpangina in infants and young children. (Funded by Sinovac Biotech; ClinicalTrials.gov number, NCT01507857.).


Asunto(s)
Enterovirus Humano A/inmunología , Enfermedad de Boca, Mano y Pie/prevención & control , Herpangina/prevención & control , Vacunas Virales/inmunología , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Preescolar , China , Método Doble Ciego , Enterovirus Humano A/genética , Femenino , Enfermedad de Boca, Mano y Pie/inmunología , Humanos , Lactante , Inyecciones Intramusculares , Masculino , Vacunas de Productos Inactivados , Vacunas Virales/administración & dosificación , Vacunas Virales/efectos adversos
11.
Bioorg Med Chem Lett ; 25(22): 5217-20, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26453007

RESUMEN

Stilbenoids, known an important phytoalexins in plants, were renowned for their beneficial effects on cardiovascular, neurological and hepatic systems. In the present study, quorum sensing inhibition activity of ten stilbenoids were tested using Chromobacterium violaceum CV026 as the bio-indicator strain and the structure-activity relationship was also investigated. Among them, resveratrol (1), piceatannol (2) and oxyresveratrol (3) showed potential anti-QS activities. At the sub-MIC concentrations, 1-3 demonstrated a statistically significant reduction of violacein in C. violaceum CV026 in a concentration dependent manner. Furthermore, the effects of 1-3 on QS regulated virulence factors in Pseudomonas aeruginosa PAO1 were also evaluated. Our results showed that the stilbenoids 1-3 can markedly decreased the production of pyocyanin and swarming motility of P. aeruginosa PAO1. Further transcriptome analyses showed that 1-3 suppressed the expression of QS-induced genes: lasR, lasI, rhlR and rhlI.


Asunto(s)
Antibacterianos/farmacología , Percepción de Quorum/efectos de los fármacos , Estilbenos/farmacología , Movimiento Celular/efectos de los fármacos , Chromobacterium/efectos de los fármacos , Chromobacterium/genética , Genes Bacterianos/efectos de los fármacos , Extractos Vegetales/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/genética , Piocianina/antagonistas & inhibidores , Relación Estructura-Actividad
12.
Arch Virol ; 160(4): 1097-104, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25680566

RESUMEN

Since 2008, Mainland China has undergone widespread outbreaks of hand, foot, and mouth disease (HFMD). In order to determine the characteristics of epidemics and enteroviruses (EV) associated with HFMD in Tianjin, in northern China, epidemiological and virological data from routine surveillance were collected and analyzed. In Tianjin, a persistent epidemic of HFMD was demonstrated during 2008-2013, involving 102,705 mild, 179 severe, and 16 fatal cases. Overall, 8234 specimens were collected from 7829 HFMD patients for EV detection during 2008-2013. Enterovirus 71 (EV-A71) and coxsackievirus A16 (CV-A16) were the dominant serotypes during 2008-2012, and they were replaced by CV-A6 as the major causative agent in 2013. Phylogenetic analysis based on complete VP1 nucleotide sequences revealed that multiple CV-A6 lineages co-circulated in Tianjin, which grouped together with strains from China and other countries and split into two distinct clusters (clusters 1 and 2). Most Tianjin strains grouped in cluster 1 and were closely related to strains from several eastern and southern provinces of China during 2012 and 2013. Estimates from Bayesian MCMC analysis suggested that multiple lineages had been transmitted silently before the outbreaks at an estimated evolutionary rate of 4.10 × 10(-3) substitutions per site per year without a specific distribution of rate variances among lineages. The sudden outbreak of CV-A6 in Tianjin during 2013 is attributed to indigenous CV-A6 lineages, which were linked to the wide spread of endemic strains around eastern and southern China.


Asunto(s)
Enterovirus Humano A/genética , Enfermedad de Boca, Mano y Pie/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , China/epidemiología , Brotes de Enfermedades , Enterovirus Humano A/clasificación , Enterovirus Humano A/aislamiento & purificación , Evolución Molecular , Femenino , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Filogenia , Adulto Joven
13.
J Immunol ; 191(4): 1637-47, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23863902

RESUMEN

Enterovirus 71 (EV71)-associated hand-foot-mouth disease has become a major threat to public health in the Asia-Pacific region. Although T cell immunity is closely correlated with clinical outcomes of EV71 infection, little is known about T cell immunity baseline against EV71 and T cell immunogenecity of EV71 Ags in the population, which has restricted our understanding of immunoprotection mechanisms. In this study, we investigated the cellular immune responses against the four structural Ags of EV71 and determined the immunohierarchy of these Ags in healthy adults. A low frequency of EV71-responsive T cells was detected circulating in peripheral blood, and broad T cell immune responses could be identified in most of the subjects after in vitro expansion. We demonstrated that the VP2 Ag with broad distribution of immunogenic peptides dominates T cell responses against EV71 compared with VP1, VP3, and VP4. Furthermore, the responses were illuminated to be mainly single IFN-γ-secreting CD4(+) T cell dependent, indicating the previous natural acute viral infection of the adult population. Conservancy analysis of the immunogenic peptides revealed that moderately variant peptides were in the majority in coxsackievirus A16 (CV-A16) whereas most of the peptides were highly variant in polioviruses. Less efficient cross-reactivity against CV-A16 might broadly exist among individuals, whereas influences derived from poliovirus vaccination would be limited. Our findings suggest that the significance of VP2 Ag should be addressed in the future EV71-responsive immunological investigations. And the findings concerning the less efficient cross-reactivity against CV-A16 and limited influences from poliovirus vaccination in EV71-contacted population would contribute to a better understanding of immunoprotection mechanisms against enteroviruses.


Asunto(s)
Antígenos Virales/inmunología , Linfocitos T CD4-Positivos/inmunología , Proteínas de la Cápside/inmunología , Enterovirus Humano A/inmunología , Enterovirus/inmunología , Enfermedad de Boca, Mano y Pie/inmunología , Poliovirus/inmunología , Subgrupos de Linfocitos T/inmunología , Adulto , Secuencia de Aminoácidos , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Enfermedades Asintomáticas , Linfocitos T CD4-Positivos/metabolismo , China/epidemiología , Reacciones Cruzadas , Epítopos de Linfocito T/inmunología , Femenino , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos , Inmunidad Celular , Interferón gamma/metabolismo , Depleción Linfocítica , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Pruebas de Neutralización , Fragmentos de Péptidos/síntesis química , Fragmentos de Péptidos/inmunología , Vacunas contra Poliovirus/inmunología , Subgrupos de Linfocitos T/metabolismo , Vacunación , Adulto Joven
14.
Pak J Pharm Sci ; 28(3): 903-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26004723

RESUMEN

The quorum sensing (QS) of pathogens has been found to affect their biofilm forming ability, making it a potential target for anti-microbial therapy. The present research aimed to evaluate the anti-QS activities of different extracts and isolated phytochemicals from Liriodendron hybrid barks and their roles in the inhibition of the growth and biofilm formation of methicillin-resistant Staphylococcus aureus (MRSA). The assays on the inhibition of QS by the five extracts (n-hexane, dichloromethane, ethyl acetate, acetone, and methanol) and eight isolated compounds were carried out by using both the indicator strains Chromobacrerium violaceum CV026 and C. violaceum ATCC12472. The in vitro effects of the five extracts and eight isolated compounds on MRSA biofilm were also preliminarily evaluated using crystal violet micro titer plate assays. The results suggested that the dichloromethane extract showed anti-QS and MRSA biofilm inhibitory activities and the n-hexane extract possessed only MRSA biofilm inhibitory effect. The dichloromethane extract could serve as a source for developing bacterial intervention strategies targeting microbial QS system. All eight isolated compounds showed no anti-QS and biofilm formation inhibiting activities. So further researches are still being required to purify and identify the compounds possessing anti-QS and biofilm inhibitory effects from the dichloromethane and n-hexane extracts.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Liriodendron , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Corteza de la Planta , Extractos Vegetales/farmacología , Percepción de Quorum/efectos de los fármacos , Benzamidas/farmacología , Cumarinas/farmacología , Pruebas de Sensibilidad Microbiana , Fitoquímicos/farmacología
15.
Arch Virol ; 159(9): 2233-41, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24696270

RESUMEN

Echovirus 33 (E33) has been infrequently detected and is less frequently associated with clinical diseases when compared with other types of enteroviruses (EVs) in China. An outbreak of E33 was identified in four schools in Hunan Province, China, in June 2013. For laboratory diagnosis, throat swabs and/or serum specimens were collected from 27 patients. E33 was isolated in cell culture and typed by molecular methods. Complete VP1 gene sequences were determined and analyzed. Specific E33 antibody was measured by virus neutralization testing. From June 3-20, 108 suspected cases were reported, and 19 were confirmed to be associated with E33 by laboratory testing, with seven virologically confirmed and 12 serologically confirmed cases. The suspected cases were in children aged 3-16 years (mean, 11 years), most of whom (94%, 102/108) were ≥6 years old. The majority of cases (98%, 106/108) presented as influenza-like illness (ILI), and two were clinically diagnosed as viral meningitis. Older children aged ≥12 years had a higher hospitalization rate (21%) than younger children (4%). A BLAST query of GenBank with the Hunan E33 strain VP1 gene sequence gave a close match to an E33 isolate from Pakistan, based on a partial VP1 gene sequence. Phylogenetic analyses of the complete E33 VP1 gene sequences from our study revealed an independent cluster with nucleotide sequences that diverge from E33 from other countries by >12%. Due to limited E33 VP1 gene sequence data in GenBank and passive EV surveillance in China and most other parts of the world (excepting hand, foot, and mouth disease surveillance in Asia), the approximate origin of Hunan E33 could not be determined.


Asunto(s)
Brotes de Enfermedades , Infecciones por Echovirus/epidemiología , Enterovirus Humano B/aislamiento & purificación , Instituciones Académicas , Adolescente , Factores de Edad , Anticuerpos Antivirales/sangre , Niño , Preescolar , China/epidemiología , Análisis por Conglomerados , Infecciones por Echovirus/patología , Infecciones por Echovirus/virología , Enterovirus Humano B/clasificación , Enterovirus Humano B/genética , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Datos de Secuencia Molecular , Filogenia , ARN Viral/genética , Análisis de Secuencia de ADN , Homología de Secuencia , Proteínas Estructurales Virales/genética
16.
Mol Med Rep ; 30(5)2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39301638

RESUMEN

Periodontitis, a common oral disease characterized by the progressive infiltration of bacteria, is a leading cause of adult tooth loss. Periodontal stem cells (PDLSCs) possess good self­renewal and multi­potential differentiation abilities to maintain the integrity of periodontal support structure and repair defects. The present study aimed to analyze the roles of Wnt7B and frizzled4 (FZD4) in the osteogenic differentiation and macrophage polarization during periodontitis using an in vitro cell model. First, Wnt7B expression in the periodontitis­affected gingival tissue of patients and lipopolysaccharide (LPS)­stimulated PDLSCs was assessed using the GSE23586 dataset and western blot analysis, respectively. In Wnt7B­overexpressing PDLSCs exposed to LPS, the capacity of osteogenic differentiation was evaluated by detecting alkaline phosphatase activity, the level of Alizarin Red S staining and the expression of genes related to osteogenic differentiation. Subsequently, conditioned medium from PDLSCs overexpressing Wnt7B was used for M0 macrophage culture. The expression of CD86 and INOS was examined using immunofluorescence staining and western blot analysis. In addition, reverse transcription­quantitative PCR was employed to examine the expression of TNF­α, IL­6 and IL­1ß in macrophages. The binding between Wnt7B and FZD4 was estimated using co­immunoprecipitation. In addition, FZD4 was silenced to perform the rescue experiments to elucidate the regulatory mechanism between Wnt7B and FZD4. The results demonstrated a decreased expression of Wnt7B in periodontitis­affected gingival tissue and in LPS­exposed PDLSCs. Wnt7B overexpression promoted the osteogenic differentiation of LPS­exposed PDLSCs and suppressed the M1 polarization of macrophages. Additionally, Wnt7B bound to FZD4 and upregulated FZD4 expression. FZD4 silencing reversed the effects of Wnt7B overexpression on the osteogenic differentiation in LPS­exposed PDLSCs and the M1 polarization of macrophages. In summary, Wnt7B plays an anti­periodontitis role by binding FZD4 to strengthen the osteogenic differentiation of LPS­stimulated PDLSCs and suppress the M1 polarization of macrophages.


Asunto(s)
Diferenciación Celular , Receptores Frizzled , Lipopolisacáridos , Macrófagos , Osteogénesis , Ligamento Periodontal , Células Madre , Proteínas Wnt , Humanos , Receptores Frizzled/metabolismo , Receptores Frizzled/genética , Osteogénesis/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Ligamento Periodontal/citología , Ligamento Periodontal/metabolismo , Proteínas Wnt/metabolismo , Proteínas Wnt/genética , Células Madre/metabolismo , Células Madre/citología , Células Madre/efectos de los fármacos , Periodontitis/metabolismo , Periodontitis/patología , Células Cultivadas , Adulto , Unión Proteica
17.
Dalton Trans ; 53(27): 11232-11236, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38915258

RESUMEN

A heterostructure composed of ZIF-67-derived nitrogen and cobalt-doped carbon enfolded silicon (C@Si) nanoparticles anchored on 2D MXene layers was constructed for boosting the performance of lithium-ion batteries (LIBs). The heterostructure anode demonstrated a high initial discharge capacity of 3021 mA h g-1 at 0.2 A g-1, retaining outstanding cycling stability with a reversible capacity of 520 mA h g-1 at 2000 mA g-1, and the coulombic efficiency remained above 97% after 500 cycles. The introduced Ti3C2 nanosheets and the cobalt-doped carbon can not only contribute to the interfacial transfer of Li+ and electrons but also buffer the volume expansion of Si.

18.
J Stomatol Oral Maxillofac Surg ; : 102042, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39244031

RESUMEN

OBJECTIVE: To explore the risk factors of radiation-induced oral mucositis (RIOM) in patients with head and neck tumors undergoing radiotherapy. METHODS: A retrospective collection was conducted on patients with head and neck tumors who underwent radiotherapy and chemotherapy in our hospital from April 1, 2015 to April 1, 2019. They were divided into an incidence group (n = 48) and a non-incidence group (n = 76) based on whether RIOM occurred, and relevant data was collected for comparison. RESULTS: There were statistically significant differences between the two groups of patients in terms of tumor type, smoking percentage, education level percentage, tumor stage, oral mucosal inflammation stage, radiotherapy dose, mucosal protectants, and oral hygiene condition(P < 0.05); The regression analysis results showed that smoking (OR=1.274, 95 % CI: 1.095-2.007), high-dose radiotherapy (OR=1.223, 95 % CI: 1.098-2.077), and poor oral hygiene (OR=1.367, 95 % CI: 1.024-2.890) were risk factors for RIOM. CONCLUSION: Smoking, high-dose radiotherapy, and poor oral hygiene were risk factors for RIOM in head and neck patients after radiotherapy and chemotherapy.

19.
J Fungi (Basel) ; 10(2)2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38392829

RESUMEN

Rice production in the Anhui province is threatened by fungal diseases. We obtained twenty-five fungal isolates from rice and wild rice leaves showing leaf spot disease collected along the Yangtze River. A phylogenetic analysis based on internal transcribed spacer (ITS), translation elongation factor 1 alpha (TEF1-α), and beta tubulin (TUB2) sequences revealed one isolate (SS-2-JB-1B) grouped with Nigrospora sphaerica, one (QY) with Nigrospora chinensis, twenty-two with Nigrospora oryzae, and one isolate (QY-2) grouped in its own clade, which are related to but clearly different from N. oryzae. Nineteen tested isolates, including sixteen strains from the N. oryzae clade and the three isolates of the other three clades, caused disease on detached rice leaves. The three isolates that did not belong to N. oryzae were also able to cause disease in rice seedlings, suggesting that they were rice pathogens. Isolate QY-2 differed from the other isolates in terms of colony morphology, cell size, and susceptibility to fungicides, indicating that this isolate represents a new species that we named Nigrospora anhuiensis. Our analysis showed that N. sphaerica, N. chinensis, and the new species, N. anhuiensis, can cause rice leaf spot disease in the field. This research provides new knowledge for understanding rice leaf spot disease.

20.
PLOS Glob Public Health ; 4(5): e0003195, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38743714

RESUMEN

The Sedia Biosciences Asanté rapid test for recent infection (RTRI) can identify HIV infections and characterize HIV-1 as recent or long-term infection via the positive verification (V) line and long-term line (LT) line, respectively. Tracking with Recency Assays to Control the Epidemic (TRACE) program uses RTRI assays. Successful implementation of TRACE requires high-quality test performance. The goal of this study is to evaluate the additional quality practices established for new kit lots prior to field use. Asanté lot quality control data from the manufacturer is reviewed by the Centers for Disease Control and Prevention International Laboratory Branch (CDC-ILB) in the Division of Global HIV and TB using. If a lot passes manufacturer quality control and CDC-ILB review, test kits are sent to CDC-ILB for further evaluation. Evaluation by CDC includes inter-rater reliability and linear regressions comparing the V and LT lines against reference data as well as V and LT line data between testers. A Bland-Altman analysis was conducted to assess bias and systematic error. Overall, CDC-ILB passed 29 (91%) out of 32 Sedia Biosciences Asanté kit lots that initially passed manufacturing quality control from July 2017 to May 2020. Regression analyses demonstrate that test kits are performing as expected with consistent R2≥0.92 for both V and LT lines. On average, inter-rater reliability kappa was 0.9, indicating a strong level of agreement. Bland-Altman analyses demonstrate high agreement with little to no systematic error and bias. Ongoing evaluation of new RTRI kit lots is important to ensure high quality test performance. Rejecting 9% of kit lots highlight the importance of continuing to work with manufacturers to ensure consistent kit production and quality assurance (QA) activities. Investing in effective QA measures, conducting both pre- and post-market performance data reviews, could help improve RTRI accuracy and outcomes in similar testing programs.

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