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BACKGROUND: Major depressive disorder is a global public health problem among older adults. Many studies show that problem-solving therapy (PST) is a cognitive behavioral approach that can effectively treat late-life depression. AIM: To summarize and assess the effects of PST on major depressive disorders in older adults. METHODS: We searched the PubMed, Web of Science, Cochrane Library, EMBASE, MEDLINE, UpToDate, and PsycINFO databases and three Chinese databases (CNKI, CBM, and Wan Fang Data) to identify articles written in English or Chinese that were published until Feb 1, 2020. Randomized controlled trials were included if they evaluated the impact of PST on major depression disorder (MDD) in older adults. Two authors of this review independently selected the studies, assessed the risk of bias, and extracted the data from all the included studies. We calculated the standard mean differences (SMDs) with 95% confidence intervals (CIs) for continuous data. We assessed heterogeneity using the I2 statistic. RESULTS: Ten studies with a total of 892 participants met the inclusion criteria. Subgroup analyses and quality ratings were performed. After problem-solving therapy, the depression scores in the intervention group were significantly lower than those in the control group (SMD = - 1.06, 95% CI - 1.52 to - 0.61, p < 0.05; I2 = 88.4%). DISCUSSION: Compared with waitlist (WL), PST has a significant effect on elderly patients with depression, but we cannot rank the therapeutic effects of all the treatment methods used for MDD. CONCLUSIONS: Our meta-analysis and systematic review suggest that problem-solving therapy may be an effective approach to improve major depressive disorders in older adults.
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Terapia Cognitivo-Comportamental , Transtorno Depressivo Maior , Idoso , Transtorno Depressivo Maior/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Morchella sextelata is an edible and medicinal fungus with high nutritional, medicinal, and economic value. Recently, M. sextelata has been produced through artificial cultivation in China, but its stable production remains problematic because the details of its growth and development process are limitedly understood. Herein, to investigate the dynamic process of M. sextelata development, we integrated the transcriptomics and metabolomics data of M. sextelata from three developmental stages: the young mushroom period (YMP), marketable mature period (MMP), and physiological maturity period (PMP). The results showed that the transcriptome changed dynamically at different stages and demonstrated the significant enrichment of pathways that regulate plant growth and development, such as N-glycan biosynthesis and carbon and purine metabolism. Similarly, small-molecule metabolites, such as D-fructose-1,6-biphosphate, which was upregulated during the YMP, dihydromyricetin, which was upregulated during the MMP, and L-citrulline, which was upregulated during the PMP, also showed phase-dependent characteristics. Then, combined analysis of the transcriptome data and metabolome traits revealed that the transcriptome may affect metabolic molecules during different growth stages of M. sextelata via specific enzymes, such as α-glucosidase and glucanase, which were included in two opposite transcriptome modules. In summary, this integration of transcriptomics and metabolomics data for understanding the vegetative growth of M. sextelata during different developmental stages implicated several key genes, metabolites, and pathways involved in the vegetative growth. We believe that these findings will provide comprehensive insights into the dynamic process of growth and development in M. sextelata and new clues for optimizing the methods for its cultivation application.
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Morita therapy was developed for common mental problems, and our aim was to evaluate the clinical effect of Morita therapy on schizophrenia. The literature was searched in 10 databases, namely, PubMed, Chinese National Knowledge Infrastructure (CNKI), Sinomed, Wanfang, Cochrane Library, UpToDate, Web of Science, Medline, PsycINFO and Embase, from inception to September 4, 2019. Random-effects models were used. For continuous results, the standardized mean differences (SMDs) and 95% confidence intervals (CIs) were calculated to synthesize the effects. Thirty studies were included, with a total of 2651 patients with schizophrenia. Compared to pharmacotherapy alone and standard care alone, Morita therapy plus pharmacotherapy and Morita therapy plus standard care both had significant effects on mental state (pooled effect size = -1.09, 95% CI: -0.35, -0.83), social functioning (pooled effect size = -0.61, 95% CI: -2.30, -0.92) and behavior (pooled effect size = 1.13, 95% CI: 0.75, 1.51). Significant heterogeneity between studies was found for mental state (I2 = 89%, p < 0.05) and social functioning (I2 = 95%, p < 0.05), but no heterogeneity was found for behavior (I2 = 0%, p = 0.84). Morita therapy has positive effects on mental state and social functioning among patients with schizophrenia, but it leads to some problems with behavior among these patients. Most included studies have unclear bias, and the forest plots show high heterogeneity among the results. Thus, Morita therapy cannot be implemented in clinical practice as a feasible strategy, the conclusion has yet to be confirmed, and new trials and future studies are desired.
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Esquizofrenia , Humanos , Esquizofrenia/terapiaRESUMO
BACKGROUND: Group B streptococcus (GBS), which asymptomatically colonises the vaginal and rectal areas of women, is a leading cause of neonatal mortality and morbidity. This study aimed to determine the prevalence and factors associated with GBS colonisation among pregnant women in Shenzhen, China. METHODS: A hospital-based cross-sectional survey was conducted, using a multistage sampling method. Pregnant women at ≥28 weeks' gestation completed a questionnaire and vaginal swabs were obtained for GBS analysis. Data were analysed by chi-squared tests and logistic regression models. RESULTS: The colonisation rate of GBS among pregnant women was 4.9%. The influencing factors associated with GBS colonisation included body mass index before pregnancy (odds ratio [OR] = 3.79, 95% CI 1.28-11.26), gestational age (OR = 5.81, 95% CI 1.20-28.15), induced abortion (OR = 0.63, 95% CI 0.40-0.98) and lotion use before pregnancy (OR = 1.59, 95% CI 1.04-2.44). CONCLUSIONS: Our findings suggest that obesity, gestational age, induced abortion and lotion use were significantly associated with GBS colonisation. Further longitudinal research is needed to establish the causal relationship and its biological mechanisms.
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Complicações Infecciosas na Gravidez/epidemiologia , Infecções Estreptocócicas/epidemiologia , Adolescente , Adulto , China/epidemiologia , Estudos Transversais , Feminino , Hospitais/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Gravidez , Prevalência , Atenção Primária à Saúde/estatística & dados numéricos , Fatores de Risco , Saúde da População Rural/estatística & dados numéricos , Streptococcus agalactiae , Saúde da População Urbana/estatística & dados numéricos , Vagina/microbiologia , Adulto JovemRESUMO
BACKGROUND: The potential factors associated with group B streptococcus (GBS) vertical transmission have not been studied in detail. STUDY DESIGN: A prospective cohort study was conducted to recruit 1815 mother-neonate pairs for GBS analysis. Pearson's chi-squared tests and generalized linear models were used to explore the risk factors for neonatal GBS colonization. RESULTS: The rate of GBS vertical transmission was 14.1%. GBS colonization in all neonates was significantly associated with maternal GBS colonization, mode of delivery, episiotomy, number of prenatal vaginal exams, parity, and hypertension. For neonates born to GBS-positive mothers, GBS vertical transmission was associated with the mode of delivery, episiotomy, and sexually transmitted diseases. For neonates born to GBS-negative mothers, neonatal GBS colonization was associated with the number of prenatal vaginal exams, parity, and hypertension. CONCLUSION: These findings suggest the need for prenatal GBS screening for pregnant women and intrapartum antimicrobial prophylaxis for GBS-colonized women.
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Hipertensão/epidemiologia , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Complicações Infecciosas na Gravidez/epidemiologia , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/transmissão , Adulto , Antibacterianos/farmacologia , China , Estudos Transversais , Feminino , Humanos , Hipertensão/microbiologia , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Modelos Lineares , Masculino , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Estudos Prospectivos , Fatores de Risco , Infecções Estreptocócicas/prevenção & controle , Streptococcus agalactiae , Vagina/microbiologia , Adulto JovemRESUMO
BACKGROUND: Streptococcus agalactiae (GBS) is a leading cause of neonatal sepsis and meningitis in many countries. This study aimed to determine the molecular characteristics of GBS colonized in mothers and their infants so as to provide implication for vaccine strategies and confirm vertical transmission. METHODS: A prospective cohort study was conducted to recruit 1815 mother-neonate pairs. All GBS isolates from pregnant women and her infants were tested for serotypes, multilocus sequence types and virulence genes. The relationship between multiple molecular characteristics of GBS isolates was tested by the correspondence analysis, and the agreement between mother-neonate paired data in molecular characteristics was analyzed using Kappa tests. RESULTS: The predominant serotypes were III, Ia and V, and the most prevalent sequence types (STs) were ST19, ST17, ST10, and ST12. All isolates carried at least one pilus island (PI). The most common combination of PIs was PI-2b alone, followed by PI-1+PI-2a and PI-2a alone, and the most prevalent alpha-like protein (alp) genes were rib, epsilon and alphaC. Moreover, a strong relationship was noted between STs, serotypes, alp genes and PIs, including ST17 associated with serotype-III/rib/PI-2b, ST19 with serotype-III/rib/PI-1+PI-2a, and ST485 with serotype-Ia/epsilon/PI-2b. The rate of GBS vertical transmission was 14.1%, and the kappa test revealed good agreement in multiple molecular characteristics among GBS-positive mother-neonate pairs. Notably, the switching of molecular characteristics was found during vertical transmission. CONCLUSIONS: Our findings underscore the value of monitoring multiple molecular characteristics so as to provide implication for multivalent strategies and gain insights into GBS vertical transmission and vertical characteristic switching.
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Transmissão Vertical de Doenças Infecciosas , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/transmissão , Streptococcus agalactiae/genética , Streptococcus agalactiae/imunologia , Feminino , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Filogenia , Gravidez , Estudos Prospectivos , Sorogrupo , Infecções Estreptocócicas/prevenção & controle , Vacinas Estreptocócicas/imunologia , Streptococcus agalactiae/classificação , Cobertura Vacinal , Virulência/genética , Fatores de Virulência/genéticaRESUMO
BACKGROUND: Group B Streptococcus (GBS) remains a leading cause of neonatal mortality and morbidity. This study aimed to determine the prevalence, antimicrobial susceptibility, serotypes, and molecular characterization of GBS colonized in neonates. METHODS: A cross-sectional study was conducted using a multistage sampling method. Swabs for GBS identification were taken from infants' ear, oral cavity, and umbilicus immediately after birth. All GBS isolates were tested for antimicrobial susceptibility, resistance genes, serotyping, multilocus sequence typing, and virulence genes. RESULTS: Of the 1,814 neonates, 1.3% tested positive for GBS, with 66.7% tested as multidrug resistant. All GBS isolates were susceptible to penicillin, but rates of resistance to tetracycline and erythromycin were high (70.8%), with the predominant resistance genes being tetM and ermB. The predominant serotype was III, followed by Ia and Ib, and the most common genotypes were sequence type (ST) 19, ST10, and ST485. Notably, we found that ST19 and ST17 isolates were associated with serotype III, resistant to tetracycline, erythromycin, and clindamycin, and carrying ermB, tetM, and rib; ST10 and ST12 isolates were associated with serotype Ib, resistant to erythromycin and clindamycin, and carrying ermB and alphaC; and ST485 isolates were associated with serotype Ia and carrying mefA/E, tetM, and epsilon. CONCLUSIONS: These findings indicate a high prevalence of multidrug-resistant GBS and specific phenotype-genotype combinations for GBS clones.
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Antibacterianos/farmacologia , Portador Sadio/microbiologia , Farmacorresistência Bacteriana , Sorogrupo , Streptococcus agalactiae/genética , Streptococcus agalactiae/fisiologia , China , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Masculino , Prevalência , Streptococcus agalactiae/classificaçãoRESUMO
BACKGROUND: Duck enteritis virus (DEV) belongs to the subfamily Alphaherpesvirinae, and information on the DEV UL41 gene is limited. METHODS: The DEV UL41 gene was cloned into the pET32a(+) vector and expressed in a prokaryotic expression system. Antiserum was raised against a bacterially expressed UL41-His fusion protein for further experiments. Transcription was quantified and UL41 protein expression levels were determined in DEV-infected cells at different time points by RT-qPCR and western blotting, respectively. DEV virions were purified by sucrose gradient centrifugation and analyzed by mass spectrometry to identify protein content. We confirmed the DEV UL41 gene kinetic class using a pharmacological test. IFA was used to analyze the intracellular localization of pUL41. RESULTS: The recombinant expression plasmid, pET-32a(+)-UL41, which highly expresses a 76.0 kDa fusion protein, was constructed and expressed in E. coli BL21 (DE3) after induction with 0.2 mM IPTG at 30 °C for 10 h, generating a specific mouse anti-UL41 protein polyclonal antibody. RT-qPCR and western blot analyses revealed that the UL41 transcript number peaked at 36 hpi, and peak protein expression occurred at 48 hpi. The pharmacological test showed that UL41 was a γ2 gene. Mass spectrometry analysis showed that pUL41 was a virion component. IFA results revealed that pUL41 was localized throughout DEV-infected cells but only localized to the cytoplasm of transfected cells. DEV pUL47 translocated pUL41 to the nuclei of DEF cells; this translocation was dependent on predicted pUL47 NLS signals (40-50 aa and 768-777 aa). CONCLUSIONS: DEV UL41 is a γ2 gene that encodes a virion structural protein, pUL41 localizes throughout DEV-infected cells but only localizes to the cytoplasm of transfected cells. pUL41 cannot autonomously localize to the nucleus, as this nuclear localization is dependent on predicted DEV pUL47 NLS signals (40-50 aa and 768-777 aa).
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Alphaherpesvirinae/genética , Alphaherpesvirinae/metabolismo , Patos/virologia , Infecções por Herpesviridae/veterinária , Doenças das Aves Domésticas/virologia , Proteínas Virais/genética , Proteínas Virais/metabolismo , Animais , Linhagem Celular , Regulação Viral da Expressão Gênica , Vetores Genéticos/genética , Transporte Proteico , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transcrição GênicaRESUMO
Streptococcus agalactiae (GBS) remains a major cause of invasive infections in neonates and pregnant women. Our aim was to evaluate the phenotypic and molecular characteristics of GBS isolates in order to reveal potential relationships among molecular characteristics and differences in genotype-phenotype characteristics between ST17 and ST19. A total of 104 GBS isolates were collected from pregnant women. All isolates were tested for antibiotic susceptibility by disk diffusion method and molecular characteristics, including antibiotic-resistant genes, virulence genes, serotypes and STs. The prevalence of GBS colonization in pregnant women was 4.9%. All isolates were susceptible to penicillin, but a high prevalence of resistance was observed for tetracycline (76.9%) and erythromycin (72.1%), with the predominant resistant genes being tet(M), tet(O), erm(B) and mef (A/E). The most frequent serotypes were III, Ia and V, and the predominant STs were ST19, ST17, ST12, ST10 and ST651. A potential correlation existed between STs, serotypes and alp genes, with ST19/III/rib and ST17/III/rib as the most prevalent clones. Notably, we observed significant differences in phenotypic and genotypic characteristics between ST17 [levofloxacin-susceptible and tet(O)-positive] and ST19 [levofloxacin-resistant and tet(O)-negative]. Our findings reveal a high prevalence of ST19/III and ST17/III and significant characteristic differences between them.
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Complicações na Gravidez/microbiologia , Infecções Estreptocócicas/microbiologia , Streptococcus agalactiae/genética , Streptococcus agalactiae/isolamento & purificação , Adulto , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana , Eritromicina/farmacologia , Feminino , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Fenótipo , Gravidez , Gestantes , Streptococcus agalactiae/classificação , Streptococcus agalactiae/efeitos dos fármacos , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Adulto JovemRESUMO
BACKGROUND: The internal transcribed spacer (ITS), RNA polymerase II second largest subunit (RPB2), and elongation factor 1-alpha (EF1α) are often used in fungal taxonomy and phylogenetic analysis. As we know, an ideal molecular marker used in molecular identification and phylogenetic studies is homogeneous within species, and interspecific variation exceeds intraspecific variation. However, during our process of performing ITS, RPB2, and EF1α sequencing on the Pleurotus spp., we found that intra-isolate sequence polymorphism might be present in these genes because direct sequencing of PCR products failed in some isolates. Therefore, we detected intra- and inter-isolate variation of the three genes in Pleurotus by polymerase chain reaction amplification and cloning in this study. RESULTS: Results showed that intra-isolate variation of ITS was not uncommon but the polymorphic level in each isolate was relatively low in Pleurotus; intra-isolate variations of EF1α and RPB2 sequences were present in an unexpectedly high amount. The polymorphism level differed significantly between ITS, RPB2, and EF1α in the same individual, and the intra-isolate heterogeneity level of each gene varied between isolates within the same species. Intra-isolate and intraspecific variation of ITS in the tested isolates was less than interspecific variation, and intra-isolate and intraspecific variation of RPB2 was probably equal with interspecific divergence. Meanwhile, intra-isolate and intraspecific variation of EF1α could exceed interspecific divergence. These findings suggested that RPB2 and EF1α are not desirable barcoding candidates for Pleurotus. We also discussed the reason why rDNA and protein-coding genes showed variants within a single isolate in Pleurotus, but must be addressed in further research. CONCLUSIONS: Our study demonstrated that intra-isolate variation of ribosomal and protein-coding genes are likely widespread in fungi. This has implications for studies on fungal evolution, taxonomy, phylogenetics, and population genetics. More extensive sampling of these genes and other candidates will be required to ensure reliability as phylogenetic markers and DNA barcodes.
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Código de Barras de DNA Taxonômico/métodos , DNA Espaçador Ribossômico/genética , Proteínas Fúngicas/genética , Fator 1 de Elongação de Peptídeos/genética , Pleurotus/classificação , RNA Polimerase II/genética , Clonagem Molecular , DNA Fúngico/genética , Filogenia , Pleurotus/genética , Polimorfismo Genético , Reprodutibilidade dos Testes , Proteínas Ribossômicas/genética , Análise de Sequência de DNA/métodos , Especificidade da EspécieRESUMO
BACKGROUND: A number of studies indicate that taurine promotes cholesterol conversion to bile acids by upregulating CYP7A1 gene expression. Few in vitro studies are concerned the concentration change of cholesterol and its product of bile acids, and the molecular mechanism of CYP7A1 induction by taurine. METHODS: The levels of intracellular total cholesterol (TC), free cholesterol (FC), cholesterol ester (EC), total bile acids (TBA) and medium TBA were determined after HepG2 cells were cultured for 24/48 h in DMEM supplemented with taurine at the final concentrations of 1/10/20 mM respectively. The protein expressions of CYP7A1, MEK1/2, c-Jun, p-c-Jun and HNF-4α were detected. RESULTS: Taurine significantly reduced cellular TC and FC in dose -and time-dependent ways, and obviously increased intracellular/medium TBA and CYP7A1 expressions. There was no change in c-Jun expression, but the protein expressions of MEK1/2 and p-c-Jun were increased at 24 h and inhibited at 48 h by 20 mM taurine while HNF4α was induced after both of the 24 h and 48 h treatment. CONCLUSION: Taurine could enhance CYP7A1 expression by inducing HNF4α and inhibiting MEK1/2 and p-c-Jun expressions to promote intracellular cholesterol metabolism.
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Anticolesterolemiantes/farmacologia , Colesterol/metabolismo , Taurina/farmacologia , Ácidos e Sais Biliares/metabolismo , Colesterol 7-alfa-Hidroxilase/genética , Colesterol 7-alfa-Hidroxilase/metabolismo , Indutores das Enzimas do Citocromo P-450/farmacologia , Avaliação Pré-Clínica de Medicamentos , Indução Enzimática/efeitos dos fármacos , Células Hep G2 , HumanosRESUMO
A novel phytase of Acidobacteria was identified from a soil metagenome, cloned, overexpressed, and purified. It has low sequence similarity (<44%) to all the known phytases. At the optimum pH (2.5), the phytase shows an activity level of 1,792 µmol/min/mg at physiological temperature (37°C) and could retain 92% residual activity after 30 min, indicating the phytase is acidophilic and acidostable. However the phytase shows poor stability at high temperatures. To improve its thermal resistance, the enzyme was redesigned using Disulfide by Design 2.0, introducing four additional disulfide bridges. The half-life time of the engineered phytase at 60°C and 80°C, respectively, is 3.0× and 2.8× longer than the wild-type, and its activity and acidostability are not significantly affected.
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6-Fitase/química , Acidobacteria/genética , Dissulfetos/química , Proteínas Recombinantes/química , 6-Fitase/genética , 6-Fitase/metabolismo , Acidobacteria/enzimologia , Dissulfetos/metabolismo , Escherichia coli , Modelos Moleculares , Mutagênese Sítio-Dirigida , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMO
In southern Tibet, ongoing vertical and horizontal motions due to the collision between India and Eurasia are monitored by large numbers of global positioning system (GPS) continuous and campaign sites installed in the past decade. Displacements measured by GPS usually include tectonic deformation as well as non-tectonic, time-dependent signals. To estimate the regional long-term tectonic deformation using GPS more precisely, seasonal elastic deformation signals associated with surface loading must be removed from the observations. In this study, we focus on seasonal variation in vertical and horizontal motions of southern Tibet by performing a joint analysis of GRACE (Gravity Recovery and Climate Experiment) and GPS data, not only using continuous sites but also GPS campaign-mode sites. We found that the GPS-observed and GRACE-modeled seasonal oscillations are in good agreements, and a seasonal displacement model demonstrates that the main reason for seasonal variations in southern Tibet is from the summer monsoon and its precipitation. The biggest loading appears from July to August in the summer season. Vertical deformations observed by GPS and modeled by GRACE are two to three times larger than horizontal oscillations, and the north components demonstrate larger amplitudes than the east components. We corrected the GPS position time series using the GRACE-modeled seasonal variations, which gives significant reductions in the misfit and weighted root-mean-squares (WRMS). Misfit (χ2 divided by degree of freedom) reductions for campaign sites range between 20% and 56% for the vertical component, and are much smaller for the horizontal components. Moreover, time series of continuous GPS (cGPS) sites near the 2015 Nepal earthquakes must be corrected using appropriate models of seasonal loading for analyzing postseismic deformation to avoid biasing estimates of the postseismic relaxation.
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By using the interaction between the sulfonated groups and silver ions, silver nanoparticles were successfully introduced onto the surface of sulfonated polyethersulfone (SPES) membranes by using vitamin C as reducing agent. The presence of silver nanoparticles on the surface of the PES/SPES hybrid membranes was characterized by UV spectrophotometer, scanning electron microscopy and transmission electron microscopy. Detailed studies on the antibacterial activity of the (PES/SPES)-Ag composites were carried out for Staphylococcus aureus, Staphylococcus albus, and Escherichia coli, for which, the composites exhibited significantly inhibition capacity. Cytocompatibility of the (PES/SPES)-Ag composites were also investigated by cell cytotoxicity and cell adhesion tests. The results indicated that after immobilizing with silver nanoparticles, the (PES/SPES)-Ag was still within the safe use range. To our knowledge, this is the first time that PES membranes have been prepared with antibacterial capacity. We anticipate that this novel and green method might lead to an expanded usage of PES with antibacterial properties in medical instruments and food processing industries in the future, and might also make a potential contribution to the fields of antibacterial chemistry.
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Antibacterianos/farmacologia , Células Endoteliais/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Polímeros/farmacologia , Prata/farmacologia , Staphylococcus/efeitos dos fármacos , Sulfonas/farmacologia , Antibacterianos/química , Ácido Ascórbico/química , Adesão Celular/efeitos dos fármacos , Humanos , Membranas Artificiais , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Tamanho da Partícula , Polímeros/química , Prata/química , Relação Estrutura-Atividade , Sulfonas/química , Ácidos Sulfônicos/química , Ácidos Sulfônicos/farmacologia , Propriedades de SuperfícieRESUMO
A new method for the functional modification of polyethersulfone (PES) is described in this paper in which PES was sulfonated by chlorosulfonic acid firstly and then chlorinated by phosphorus pentachloride. Thereby, chlorosulfonic groups (-SO2Cl) were introduced in PES successfully, and the degree of the chlorosulfonation was about 15%. Since the chlorosulfonic group is reactive enough towards the amino group (-NH2), the conformation of chlorosulfonic-based covalent bonding functional route could further extend the PES application area with versatile functionality. In this article, hydroxyl (-OH), carboxyl (-COOH), amino (-NH2) and methyl (-CH3) groups were grafted onto a PES matrix through the reaction of chlorosulfonic groups and the amino groups. The functional groups have effects on protein adsorption and cell behavior. The membrane modified with an amino group was in favor of cell adhesion and proliferation, and the membrane modified with hydroxyl and methyl did not so well as the membrane modified with an amino group, which will give guidance for biomaterial modification.