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1.
ACS Appl Mater Interfaces ; 16(17): 21943-21952, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38635833

RESUMO

Lithium-sulfur (Li-S) batteries are one of the most promising high-energy density secondary batteries due to their high theoretical energy density of 2600 Wh kg-1. However, the sluggish kinetics and severe "shuttle effect" of polysulfides are the well-known barriers that hinder their practical applications. A carefully designed catalytic host of sulfur may be an effective strategy that not only accelerates the conversion of polysulfides but also limit their dissolution to mitigate the "shuttle effect." Herein, in situ surface-phosphided Ni0.96Co0.03Mn0.01O (p-NCMO) oxide microspheres are prepared via gas-phase phosphidation as a catalytic host of sulfur. The as-prepared unique heterostructured microspheres, with enriched surface-coated metal phosphide, exhibit superior synergistic effect of catalytic conversion and absorption of the otherwise soluble intermediate polysulfides. Correspondingly, the sulfur cathode exhibits excellent electrochemical performance, including a high initial discharge capacity (1162 mAh gs-1 at 0.1C), long cycling stability (491 mAh gs-1 after 1000 cycles at 1C), and excellent rate performance (565 mAh gs-1 at 5C). Importantly, the newly prepared sulfur cathode shows a high areal capacity of 4.0 mAh cm-2 and long cycle stability under harsh conditions (high sulfur loading of 5.3 mg cm-2 and lean electrolyte/sulfur ratio of 5.8 µL mg-1). This work proposes an effective strategy to develop the catalytic hosts of sulfur for achieving high-performance Li-S batteries via surface phosphidation.

2.
Int J Biol Macromol ; 253(Pt 2): 126841, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37696368

RESUMO

The natural characteristics of protein/polysaccharide-based hydrogels, as a potential drug delivery platform, have attracted extensive attention. Probiotics have attracted renewed interest in drug research because of their beneficial effects on host health. The idea of using probiotics loaded on protein/polysaccharide-based hydrogels as potential drugs to treat different diseases has been put forward and shows great prospects. Based on this, in this review, we highlight the design strategy of hydrogels loaded probiotic-mediated therapy systems and review the potential diseases that have been proved to be treatable in the laboratory, including promoting wound healing and improving intestinal health and vaginal health, and discuss the challenges existing in the current design.


Assuntos
Hidrogéis , Polissacarídeos , Hidrogéis/farmacologia , Polissacarídeos/farmacologia , Cicatrização , Sistemas de Liberação de Medicamentos
3.
Br J Clin Pharmacol ; 89(4): 1491-1494, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36440759

RESUMO

Ceftriaxone is widely used in children with community-acquired pneumonia. Currently, there are no available data regarding epithelial lining fluid (ELF) concentrations of ceftriaxone in children. Thus, blood and bronchoalveolar lavage fluids samples were collected by using an opportunistic sampling design, then we determined plasma and ELF concentrations in 22 children (0.5-11.7 years), with a total of 36 plasma and 22 ELF samples available for analysis. Ceftriaxone plasma and ELF concentrations ranged from 1.07 to 138.71 mg/L and from 0.61 to 26.69 mg/L, respectively. Ceftriaxone concentration in ELF was 12.18 ± 5.15 (mean ± standard deviation) times higher than that in plasma, ranging from 1.29 to 20.44.


Assuntos
Ceftriaxona , Pneumonia , Humanos , Criança , Pneumonia/tratamento farmacológico , Líquido da Lavagem Broncoalveolar , Antibacterianos
4.
J Clin Pharmacol ; 61(4): 538-546, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32996155

RESUMO

Amoxicillin is used to treat various bacterial infections (eg, pneumonia, sepsis, meningitis) in infants. Despite its frequent use, there is a lack of population pharmacokinetic studies in infants, resulting in a substantial variability in dosing regimens used in clinical practice. Therefore, the objective of this study was to evaluate the population pharmacokinetics of intravenous amoxicillin in infants and suggest an optimal dosage regimen. Blood samples were collected for the determination of amoxicillin concentrations using an opportunistic sampling strategy. The amoxicillin plasma concentrations were determined using high-performance liquid chromatography. Population pharmacokinetic analysis was performed using NONMEM. A total of 62 pharmacokinetic samples from 47 infants (age range, 0.09 to 2.0 years) were available for analysis. A 2-compartment model with first-order elimination was most suitable to describe the population pharmacokinetics of amoxicillin, and covariate analysis showed that only current body weight was a significant covariate. Monte Carlo simulation demonstrated that the currently used dosage regimen (25 mg/kg twice daily) resulted in only 22.4% of infants reaching their pharmacodynamic target, using a minimum inhibitory concentration (MIC) break point of 2 mg/L, whereas a dosage regimen (60 mg/kg thrice daily), as supported by the British National Formulary for Children, resulted in 80.9% of infants achieving their pharmacodynamic target. It is recommended to change antibiotics for infections caused by Escherichia coli (MIC = 8.0 mg/L) because only 27.9% of infants reached target using 60 mg/kg thrice daily.


Assuntos
Amoxicilina/farmacocinética , Antibacterianos/farmacocinética , Modelos Biológicos , Amoxicilina/farmacologia , Antibacterianos/farmacologia , Simulação por Computador , Humanos , Lactente , Testes de Sensibilidade Microbiana , Método de Monte Carlo
5.
Antimicrob Agents Chemother ; 64(11)2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32816735

RESUMO

Ceftriaxone is a third-generation cephalosporin used to treat infants with community-acquired pneumonia. Currently, there is a large variability in the amount of ceftriaxone used for this purpose in this particular age group, and an evidence-based optimal dose is still unavailable. Therefore, we investigated the population pharmacokinetics of ceftriaxone in infants and performed a developmental pharmacokinetic-pharmacodynamic analysis to determine the optimal dose of ceftriaxone for the treatment of infants with community-acquired pneumonia. A prospective, open-label pharmacokinetic study of ceftriaxone was conducted in infants (between 1 month and 2 years of age), adopting an opportunistic sampling strategy to collect blood samples and applying high-performance liquid chromatography to quantify ceftriaxone concentrations. Developmental population pharmacokinetic-pharmacodynamic analysis was conducted using nonlinear mixed effects modeling (NONMEM) software. Sixty-six infants were included, and 169 samples were available for pharmacokinetic analysis. A one-compartment model with first-order elimination matched the data best. Covariate analysis elucidated that age and weight significantly affected ceftriaxone pharmacokinetics. According to the results of a Monte Carlo simulation, with a pharmacokinetic-pharmacodynamic target of a free drug concentration above the MIC during 70% of the dosing interval (70% fT>MIC), regimens of 20 mg/kg of body weight twice daily for infants under 1 year of age and 30 mg/kg twice daily for those older than 1 year of age were suggested. The population pharmacokinetics of ceftriaxone were established in infants, and evidence-based dosing regimens for community-acquired pneumonia were suggested based on developmental pharmacokinetics-pharmacodynamics.


Assuntos
Ceftriaxona , Infecções Comunitárias Adquiridas , Adulto , Antibacterianos/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Humanos , Lactente , Testes de Sensibilidade Microbiana , Método de Monte Carlo , Estudos Prospectivos
6.
Eur J Clin Pharmacol ; 76(11): 1547-1556, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32583354

RESUMO

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


Assuntos
Ceftriaxona/farmacocinética , Infecções Comunitárias Adquiridas/tratamento farmacológico , Pneumonia/tratamento farmacológico , Ceftriaxona/administração & dosagem , Criança , Pré-Escolar , Humanos , Modelos Biológicos , Método de Monte Carlo
7.
World J Emerg Med ; 10(1): 5-13, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30598712

RESUMO

BACKGROUND: For emergency department (ED) patients, risk assessment, prophylaxis, early diagnosis and appropriate treatment of venous thromboembolism (VTE) are essential for preventing morbidity and mortality. This study aimes to investigate knowledge amongst emergency medical staff in the management of VTE. METHODS: We designed a questionnaire based on multiple scales. The questionnaire was distributed to the medical and nursing clinical staff in the large urban ED of a medical center in Northern China. Data was described with percentages and the Kruskal-Wallis test was used to compare ranked data between different groups. The statistical analysis was done using the SPSS 22.0 software. RESULTS: In this survey, 180 questionnaires were distributed and 174 valid responses (response rate of 96.67%) were collected and analyzed. In scores of VTE knowledge, no significant differences were found with respect to job (doctor vs. nurse), the number of years working in clinical medicine, education level, and current position, previous hospital experience and nurses' current work location within the ED. However, in pair wise comparison, we found participants who worked in ED for more than 5 years (n=83) scored significantly higher on the questionnaire than those under 5 years (n=91) (95.75 vs. 79.97, P=0.039). There was a significant difference in some questions based on gender, age, job, and nurse work location, number of working years, education level, and different ED working lifetime. CONCLUSION: Our survey has shown deficiencies among ED medical staff in knowledge and awareness of the management of VTE. We recommend several changes be considered, such as the introduction of an interdisciplinary workshop for medical staff; the introduction of a standardized VTE protocol; a mandatory study module on VTE for new physicians and nurses; the introduction of a mandatory reporting system for adverse events (including VTE).

8.
Artigo em Inglês | MEDLINE | ID: mdl-29378703

RESUMO

Ceftazidime, a third-generation cephalosporin, can be used for the treatment of adults and children with infections due to susceptible bacteria. To date, the pediatric pharmacokinetic data are limited in infants, and therefore we aimed to evaluate the population pharmacokinetics of ceftazidime in infants and to define the appropriate dose to optimize ceftazidime treatment. Blood samples were collected from children treated with ceftazidime, and concentrations of the drug were quantified by high-performance liquid chromatography with UV detection (HPLC-UV). A population pharmacokinetic analysis was performed using NONMEM software (version 7.2.0). Fifty-one infants (age range, 0.1 to 2.0 years) were included. Sparse pharmacokinetic samples (n = 90) were available for analysis. A one-compartment model with first-order elimination showed the best fit with the data. A covariate analysis identified that body weight and creatinine clearance (CLCR) were significant covariates influencing ceftazidime clearance. Monte Carlo simulation demonstrated that the currently used dosing regimen of 50 mg/kg twice daily was associated with a high risk of underdosing in infants. In order to reach the target of 70% of the time that the free antimicrobial drug concentration exceeds the MIC (fT>MIC), 25 mg/kg every 8 h (q8h) and 50 mg/kg q8h were required for MICs of 4 and 8 mg/liter, respectively. The population pharmacokinetic characteristics of ceftazidime were evaluated in infants. An evidence-based dosing regimen was established based on simulation.


Assuntos
Antibacterianos/farmacocinética , Ceftazidima/farmacocinética , Antibacterianos/farmacologia , Ceftazidima/farmacologia , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Método de Monte Carlo
9.
Journal of Forensic Medicine ; (6): 257-260, 2016.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-984842

RESUMO

OBJECTIVES@#To investigate the genetic polymorphism of SNP located in the 5' region of the vascular endothelial growth factor (VEGF) gene in Han population in Guangdong and provide basic data for forensic application and population genetics research.@*METHODS@#The genetic polymorphisms of 4 SNP loci (rs699947, rs1570360, rs833061, rs2010963) within 5' region of VEGF gene of 184 unrelated individuals in Han population in Guangdong were analyzed by DNA micro sequencing technology SNaPshot. The statistical analysis was carried out by PowerMarker v3.25 software.@*RESULTS@#The genotype distributions of the 4 SNP loci within 5' region of VEGF gene of 184 unrelated individuals in Han population in Guangdong were in accordance with Hardy-Weinberg equilibrium (P>0.05) and 3 kinds of genotypes were detected from each loci. There was high linkage disequilibrium between the rs833061 and rs699947 SNP loci. Six haplotypes were observed, while the frequency of C-G-T-C, C-G-T-G, A-A-C-G and A-G-C-G were more than 10%, which were the main haplotypes. The discrimination probabilities (DP) of rs699947, rs833061, and rs2010963 loci were between 0.583 and 0.634, with the power of exclusion (PE) between 0.133 and 0.144. The DP and PE of haplotypes of 4 SNP were 0.868 and 0.438, respectively.@*CONCLUSIONS@#There are great polymorphisms in the 5' region of VEGF gene in Han population in Guangdong, which could be used as genetic indexes for individual identification and paternity testing, as well as association analysis of the related diseases.


Assuntos
Humanos , Povo Asiático/genética , China , Genética Populacional , Genótipo , Haplótipos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Fator A de Crescimento do Endotélio Vascular/genética
10.
Journal of Forensic Medicine ; (6): 184-188, 2016.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-984832

RESUMO

OBJECTIVES@#To investigate the single nucleotide polymorphism (SNP) and haplotypes in differentially methylated region (DMR) upstream of H19 gene in Guangdong Han population.@*METHODS@#The PIA typing and restriction enzyme McrBC and HpaⅡ were used to digest the genomic DNA and obtain the individual uniparental DNA template strand. The data of uniparental SNP alleles, genotypes and haplotypes in DMR upstream of H19 gene were obtained by sequencing.@*RESULTS@#A total of 13 SNPs (rs10840167, rs2525883, rs12417375, rs4930101, rs2525882, rs2735970, rs2735971, rs11042170, rs2735972, rs10732516, rs2071094, rs2107425, and rs4930098) and one mutation locus (g7351c) were found. All loci followed the Hardy-Weinberg equilibrium (P>0.05) by statistical analysis. Except for rs12417375 (DP=0.279) locus, the DP of remaining 12 SNPs were 0.446-0.614, and the g7351c mutation locus (DP=0.013) was the particular loci of the Southern Chinese Han population. Eight haplotypes (designated as haplotype 1-8) were detected, in which 3 haplotypes had not yet been reported and the DP, PIC, PE and H were 0.891, 0.714, 0.524 and 0.758, respectively.@*CONCLUSIONS@#Obtained by PIA typing, the SNP in DMR upstream of H19 gene and its haplotypes genetic marker system have a high determination power and show a good practical value in forensic identification.


Assuntos
Humanos , Alelos , Povo Asiático/genética , China , DNA , Frequência do Gene , Marcadores Genéticos , Genética Populacional , Genótipo , Haplótipos/genética , Polimorfismo de Nucleotídeo Único
11.
Mol Cell Biochem ; 351(1-2): 109-16, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21246261

RESUMO

Tumor development has long been known to resemble abnormal embryogenesis. The ESC self-renewal gene NANOG is purportedly expressed in some epithelial cancer cells and solid tumors, but a casual role in tumor development has remained unclear. In order to more comprehensively elucidate the relationship between human Nanog and tumorigenesis, the hNanog was ectopically expressed in the 293 cell line to investigate its potential for malignant transformation of cells both in vitro and in vivo. Here we provide compelling evidence that the overexpression of hNanog resulted in increased cell proliferation, anchor-independent growth in soft agar, and formation of tumors after subcutaneous injection of athymic nude mice. Pathologic analysis revealed that these tumors were poorly differentiated. In analysis of the underlying molecular mechanism, two proteins, FAK and Ezrin, were identified to be upregulated in the hNanog expressing 293 cells. Our results demonstrate that hNanog is a potent human oncogene and has the ability to induce cellular transformation of human cells.


Assuntos
Transformação Celular Neoplásica/genética , Proteínas de Homeodomínio/genética , Animais , Linhagem Celular , Proteínas do Citoesqueleto/metabolismo , Eletroforese em Gel Bidimensional , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Humanos , Camundongos , Camundongos Nus , Proteína Homeobox Nanog , Oncogenes , Regulação para Cima
12.
Huan Jing Ke Xue ; 27(7): 1373-6, 2006 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16881312

RESUMO

Sorption behavior of p-nitrophenol by sediment in the presence of both cetylpyridinium chloride (CPC) and Pb(NO3)2 were investigated. The concurrence of Pb(NO3)2 inhibited the enhancement of sorption induced by CPC. The removal effect of pnitrophenol from sediment by compounding of CPC and Pb(NO3)2 presented antagonistic effect. At a given concentration of CPC, the antagonistic effect increased with increasing of the initial concentration of Pb(NO3)2. The antagonistic effect was also dependent on CPC concentrations. At the initial concentration below 3000 mg/L(the equilibrium concentration was below CMC), the antagonistic effect was especially significant. With the increase of the concentration of CPC, the antagonistic effect decreased gradually. Especially at the higher concentration above CMC, the effect went to be an independent effect just induced by CPC. In addition, the study also indicate that Pb2+ and CPC may not compete for the same adsorption sites.


Assuntos
Cetilpiridínio/química , Sedimentos Geológicos/química , Chumbo/química , Nitratos/química , Nitrofenóis/análise , Poluentes Químicos da Água/análise , Adsorção , Nitrofenóis/química , Tensoativos/química , Poluentes Químicos da Água/química
13.
Sheng Wu Gong Cheng Xue Bao ; 20(3): 361-5, 2004 May.
Artigo em Chinês | MEDLINE | ID: mdl-15971606

RESUMO

The production of recombinant protein is one of the major successes of biotechnology, animal cells are required to synthesize proteins with the appropriate post-translational modifications. Transgenic animal mammary gland bioreactor are being used for this purpose. Gene targeting is a more powerful method to produce mammary gland bioreactor, and nuclear transfer from cultured somatic cells provides an wonderful means of cell-mediated transgensis. Here we describe efficient and reproducible gene targeting in goat fetal fibroblasts to place the human tissue plasminogen activator mutant (ht-PAm) cDNA at the beta-casein locus, and would produce the transgenic goat by nuclear transfer. To construct the gene targeting vector pGBC4tPA, the milk goat beta-casein genomic DNA sequence for homologous arms had been cloned firstly. The left arm was 6.3 kb fragment including goat beta-casein gene 5' flanking sequence, and the right arm was 2.4 kb fragement including beta-casein gene from exon 8 to exon 9. The ht-PAm cDNA was subcloned in the goat beta-casein gene exon 2, and the endogenous start condon was replaced by that of ht-PAm. The bacterial neomycin (neo) gene as positive selection marker gene, was placed in the beta-casein gene intron 7, the thymidine kinase (tk) as the negative selection marker gene, was just outside the right arm. The validity of the positive-negative selection vector (PNS), was tested, and targeting homologous recombination (HR) were elevated to 5-fold with the negative selection marker using the drug GANC. The DNA fragment in which two LoxP sequence was delected effectively using Cre recombinase in vitro. Goat fetal fibroblasts were thawed and cultured to subconfluence before transfection, about 10(7) fibroblasts were electoporated at 240V, 600 microF in 0.8 mL PBS buffer containing linear pGBC4tPA. transfected cells were cultured in collagen-coated 96-wellplate for 24h without selection, then added the drug G418 (600 microg/mL) and GANC (2 micromol/L). After 12 days of selection, well separated G418r/GANCr clones were isolated and expanded in 24-wellplate. 244 clones were selected, and only 90 clones could grow and be tested by PCR screening for targeting. The primary result demonstrated that 31 targeting cell clones with homologous recombination events were obtained, and 2 cell clones was verified by DNA sequence analysis on the homologous recombination region.


Assuntos
Animais Geneticamente Modificados , Caseínas/genética , Técnicas de Introdução de Genes , Cabras/genética , Ativador de Plasminogênio Tecidual/genética , Animais , Animais Geneticamente Modificados/genética , Sequência de Bases , Clonagem de Organismos , DNA Complementar/genética , Engenharia Genética/métodos , Vetores Genéticos/síntese química , Humanos , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/metabolismo , Dados de Sequência Molecular , Proteínas Mutantes/genética
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