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1.
J Gastroenterol Hepatol ; 38(12): 2238-2246, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37926431

RESUMO

BACKGROUND AND AIM: Healthcare-associated infections (HAIs) after pancreaticoduodenectomy (PD) are one of the common postoperative complications. This study aims to investigate the epidemiology of postoperative HAIs in patients with open pancreaticoduodenectomy (OPD) and robotic pancreaticoduodenectomy (RPD). METHODS: This retrospective cohort study described the trend of HAIs in patients undergoing PD from January 2013 to December 2022 at a tertiary hospital. Patients were divided into OPD and RPD, and the HAIs and outcomes were compared. RESULTS: Among 2632 patients who underwent PD, 230 (8.7%, 95% confidence interval [CI] 7.7-9.9%) were diagnosed with HAIs, with a decreasing trend from 2013 to 2022 (P < 0.001 for trend). The incidence of postoperative HAIs was significantly higher in patients with OPD than RPD (9.6% vs 5.8%; P = 0.003). The incidence of HAIs for patients with OPD showed a decreasing trend (P = 0.001 for trend), and the trend for RPD was not significant (P = 0.554 for trend). Logistic regression showed that RPD was significantly associated with postoperative HAIs after adjusting for covariates (adjusted odds ratio = 0.654; 95% CI 0.443-0.965; P = 0.032), especially in the subgroup of patients without preoperative biliary drainage (adjusted odds ratio = 0.486; 95% CI 0.292-0.809; P = 0.006). Regarding clinical outcomes, RPD has a shorter length of stay and a more expensive charge than OPD (all P < 0.05). CONCLUSION: Postoperative HAIs in patients with PD showed a decreasing trend in recent years, especially in OPD. RPD was significantly associated with reduced postoperative HAIs and length of stay, although the charge is more expensive. Attention should be paid to postoperative HAIs in OPD, and it is imperative to continue reducing the costs of RPD.


Assuntos
Laparoscopia , Neoplasias Pancreáticas , Procedimentos Cirúrgicos Robóticos , Humanos , Estudos Retrospectivos , Pancreaticoduodenectomia/efeitos adversos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Neoplasias Pancreáticas/cirurgia , Tempo de Internação , Complicações Pós-Operatórias/etiologia , Atenção à Saúde
2.
Appl Microbiol Biotechnol ; 103(14): 5821-5830, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31101943

RESUMO

Herein we report that peptide dendrimers G3KL and TNS18, which were recently reported to control multidrug-resistant bacteria such as Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii, strongly inhibit biofilm formation by P. aeruginosa PA14 below their minimum inhibitory concentration (MIC) value, under which conditions they also strongly affect swarming motility. Eradication of preformed biofilms, however, required concentrations above the MIC values. Scanning electron microscopy observation and confocal laser scanning micrographs showed that peptide dendrimers can destroy the biofilm morphological structure and thickness in a dose-dependent manner, even make the biofilm dispersed completely. Membrane potential analysis indicated that planktonic cells treated with peptide dendrimers presented an increase in fluorescence intensity, suggesting that cytoplasmic membrane could be the target of G3KL and TNS18 similarly to polymyxin B. RNA-seq analysis showed that the expressions of genes in the arnBCADTEF operon-regulating lipid A modification resulting in resistance to AMPs are differentially affected between these three compounds, suggesting that each compound targets the cell membrane but in different manner. Potent activity on planktonic cells and biofilms of P. aeruginosa suggests that peptide dendrimers G3KL and TNS18 are promising candidates of clinical development for treating infections.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Dendrímeros/farmacologia , Peptídeos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Descoberta de Drogas , Potenciais da Membrana/efeitos dos fármacos , Testes de Sensibilidade Microbiana
3.
Plant Cell Rep ; 38(9): 1165-1180, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31161264

RESUMO

KEY MESSAGE: Arabidopsis photorespiratory gene AtAGT1 is important for the growth and development of root, the non-photosynthetic organ, and it is involved in a complex metabolic network and salt resistance. AtAGT1 in Arabidopsis encodes an aminotransferase that has a wide range of donor:acceptor combinations, including Asn:glyoxylate. Although it is one of the photorespiratory genes, its encoding protein has been suggested to function also in roots to metabolize Asn. However, experimental data are still lacking. In this study, we investigated experimentally the function of AtAGT1 in roots and our results uncovered its importance in root development during seedling establishment after seed germination. Overexpression of AtAGT1 in roots promoted both the growth of primary root and outgrowth of lateral roots. To further elucidate the molecular mechanisms underlying, amino acid content and gene expression in roots were analyzed, and results revealed that AtAGT1 is involved in a complex metabolic network and salt resistance of roots.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Reguladores de Crescimento de Plantas/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Expressão Gênica , Germinação , Plantas Geneticamente Modificadas , Tolerância ao Sal , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Transaminases/genética , Transaminases/metabolismo
4.
FEMS Yeast Res ; 18(8)2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30107496

RESUMO

As a traditional ethanol-producing microorganism, Saccharomyces cerevisiae is an ideal host for consolidated bioprocessing. However, expression of heterologous cellulase increases the metabolic burden in yeast, which results in low cellulase activity and poor cellulose degradation efficiency. In this study, cellulase-expressing yeast strains that could efficiently degrade different cellulosic substrates were created by optimizing cellulase ratios through a POT1-mediated δ-integration strategy. Metabolic engineering strategies, including optimization of codon usage, promoter and signal peptide, were also included in this system. We also confirmed that heterologous cellulase expression in cellulosic yeast induced the unfolded protein response. To enhance protein folding capacity, the endoplasmic reticulum chaperone protein BiP and the disulfide isomerase Pdi1p were overexpressed, and the Golgi membrane protein Ca2+/Mn2+ ATPase Pmr1p was disrupted to decrease the glycosylation of cellulase. The resultant strain, SK18-3, could produce 5.4 g L-1 ethanol with carboxymethyl-cellulose. Strain SK12-50 achieved 4.7 g L-1 ethanol production with phosphoric acid swollen cellulose hydrolysis. When Avicel was used as the substrate, 3.8 g L-1 ethanol (75% of the theoretical maximum yield) was produced in SK13-34. This work will significantly increase our knowledge of how to engineer optimal yeast strains for biofuel production from cellulosic biomass.


Assuntos
Celulase/genética , Celulase/metabolismo , Celulose/metabolismo , Etanol/metabolismo , Engenharia Metabólica/métodos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Códon , Expressão Gênica , Regiões Promotoras Genéticas , Sinais Direcionadores de Proteínas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
5.
Plant Mol Biol ; 94(4-5): 419-431, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28455648

RESUMO

The importance of the phosphorylated pathway (PPSB) of L-serine (Ser) biosynthesis in plant growth and development has been demonstrated, but its specific role in leaves and interaction with photorespiration, the main leaf Ser biosynthetic pathway at daytime, are still unclear. To investigate whether changes in biosynthesis of Ser by the PPSB in leaves could have an impact on photorespiration and plant growth, we overexpressed PSP1, the last enzyme of this pathway, under control of the Cauliflower Mosaic Virus 35S promoter in Arabidopsis thaliana. Overexpressor plants grown in normal air displayed larger rosette diameter and leaf area as well as higher fresh and dry weight than the wild type. By contrast, no statistically significant differences to the wild type were observed when the overexpressor seedlings were transferred to elevated CO2, indicating a relationship between PSP1 overexpression and photorespiration. Additionally, the transgenic plants displayed higher photorespiration, an increase in CO2 net-uptake and stronger expression in the light of genes encoding enzymes involved in photorespiration. We further demonstrated that expression of many genes involved in nitrogen assimilation was also promoted in leaves of transgenic plants and that leaf nitrate reductase activity increased in the light, too, although not in the dark. Our results suggest a close correlation between the function of PPSB and photorespiration, and also nitrogen metabolism in leaves.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Monoéster Fosfórico Hidrolases/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Dióxido de Carbono/metabolismo , Clonagem Molecular , DNA de Plantas , Ácido Glutâmico/metabolismo , Glutamina/metabolismo , Ácidos Cetoglutáricos/metabolismo , Nitrogênio/metabolismo , Monoéster Fosfórico Hidrolases/genética , Fotossíntese/fisiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sacarose/metabolismo
6.
FEMS Yeast Res ; 17(6)2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28922845

RESUMO

In biotechnological industry, increased expression cassette stability and copy number serve as important means of maintaining consistently high production levels of heterologous proteins in Saccharomyces cerevisiae. In this study, we combined δ sequences for site-specific integration with TPI1 gene from Schizosaccharomyces pombe (POT1) as a selection marker to realize high-copy integration and stable expression of heterologous proteins in S. cerevisiae. With the newly developed POT1 platform, a 32-copy integration of enhanced green fluorescent protein (EGFP) expression cassette was obtained in a single round and was stably maintained after 100 generations of growth in a rich complex medium. Talaromyces emersonii cellobiohydrolase I gene was synthesized with S. cerevisiae codon bias and expressed under the control of TPI1 promoter and terminator via POT1-mediated δ-integration; the highest specific activity yielded 238 mU g-1 of dry cell weight when p-nitrophenyl-ß-D-cellobioside was used as substrate, whereas the highest activity in cellulose hydrolysis reached 67% Avicel conversion. POT1-mediated δ-integration produces high protein levels over a wide dynamic range and enables broad applications in metabolic engineering and synthetic biology.


Assuntos
Dosagem de Genes , Expressão Gênica , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Celulose 1,4-beta-Celobiosidase/análise , Celulose 1,4-beta-Celobiosidase/genética , Eurotiales/enzimologia , Eurotiales/genética , Genes Reporter , Instabilidade Genômica , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Proteínas Recombinantes/biossíntese , Recombinação Genética , Schizosaccharomyces/enzimologia , Schizosaccharomyces/genética
7.
Protein Expr Purif ; 128: 22-8, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27474238

RESUMO

Hydrophobins are proteins produced by filamentous fungi with high natural-surfactant activities and that can self-assemble in interfaces of air-water or solid-water to form amphiphilic membranes. Here, we reported a high-yield fermentation method for hydrophobin HGFI from Grifola frondosa in Pichia pastoris, attaining production of 300 mg/L by keeping the dissolved oxygen level at 15%-25% by turning the methanol-feeding speed. We also developed a novel HGFI-purification method enabling large-scare purification of HGFI, with >90% recovery. Additionally, we observed that hydrophobin HGFI in fermentation broth precipitated at pH < 7.0 and temperatures >90 °C. We also identified the structure and properties of proteins purified by this method through atomic force microscopy, circular dichroism, X-ray photoelectron spectroscopy, and water-contact angle measurement, which is similar to protein purification by ultrafiltration without heating treatment that enables our method to maintain native HGFI structure and properties. Furthermore, the purification method presented here can be applied to large-scale purification of other type I hydrophobins.


Assuntos
Proteínas Fúngicas , Expressão Gênica , Grifola/genética , Pichia/crescimento & desenvolvimento , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Grifola/metabolismo , Pichia/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
8.
Wei Sheng Wu Xue Bao ; 55(4): 440-7, 2015 Apr 04.
Artigo em Chinês | MEDLINE | ID: mdl-26211318

RESUMO

OBJECTIVE: To accelerate the formation of nisin through overexpressing 6-phosphofructokinase gene pfk in nisin-producer Lactococcus lactis N8. METHODS: The genes of pfk and pkaC encoding the catalytic subunit of cAMP-dependent protein kinase were cloned into the vector pMG36e andtransformed into L. lactis N8, resulting in the recombinant strain L. lactis N8-pMG36e-pfk-pkaC. Several biochemical and physological factors, including growth profiles, activity of 6-phosphofructokinase, expression of nisA , antibacterial activity of supernatants and nisin titer, were monitored to investigate the differences between the recombinant strain and the parental strain. RESULTS: No significant difference was observed with respect to the growth patterns of the recombinant strain and the wild type. As expected, the biological activity of PFK in recombinant strain was increased for all examined samples. Correspondingly, the yield of nisin was increased by 20% in the recombinant strain after fermentation for 10 hours, which could be attributed to the accelerated biosynthesis of nisin. As a result, the fermentation cycle was reduced about 2 hours. Meanwhile, different concentration of glucose did not affect the formation of nisin. CONCLUSION: The overexpression of pfk and pkaC genes in the nisin-producer strain can effectively accelerate nisin biosynthesis.


Assuntos
Antibacterianos/biossíntese , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Lactococcus lactis/metabolismo , Nisina/biossíntese , Fosfofrutoquinases/genética , Proteínas de Bactérias/metabolismo , Fermentação , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Lactococcus lactis/genética , Lactococcus lactis/crescimento & desenvolvimento , Fosfofrutoquinases/metabolismo
9.
Infect Dis (Lond) ; 56(4): 320-329, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38317598

RESUMO

BACKGROUND: Nosocomial infections (NIs) are the most frequent adverse events among patients and cause a heavy burden on both health and economics. To investigate epidemiology of NIs and identify risk factors for NIs by integrating continuous long-term surveillance data. METHODS: We performed an observational study among inpatients at the Chinese People's Liberation Army General Hospital between January 1, 2010, and December 31, 2019. Infection rates, mortality rates and percentage of NIs were calculated. Trends of yearly infection rates by pathogens were assessed using Mann-Kendall trend test. Controls were matched to cases (2:1) by age (±2 years), sex, admission date (±1 year) and admission diagnosis, and conditional logistic regression was used to estimate odds ratios. RESULTS: A total of 1,534,713 inpatients were included among which 33,468 NIs cases occurred with an infection rate of 2.18%. The most common infections were respiratory system infection (52.22%), bloodstream infection (17.60%), and genitourinary system infection (15.62%). Acinetobacter. baumannii (9.6%), Klebsiella. pneumoniae (9.0%), Pseudomonas. aeruginosa (8.6%), Escherichia. coli (8.6%) and Enterococcus. faecium (5.0%) were the top five isolated pathogens. Infection rates of K. pneumoniae and carbapenems-resistant K. pneumoniae significantly increased. Prior ICU stay, surgery, any device placement (including central venous catheter, mechanical ventilation, urinary catheter, and tracheotomy), prior use of triple or more antibiotics combinations, carbapenem, and ß-Lactamase inhibitors were significantly associated with NIs. CONCLUSION: K. pneumoniae has the potential to cause a clinical crisis with increasing infection rates and carbapenem resistance. Clinical management of invasive operations and antibiotics use should be further strengthened.


Assuntos
Infecção Hospitalar , Humanos , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Estudos de Casos e Controles , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/tratamento farmacológico , Farmacorresistência Bacteriana , Escherichia coli , Klebsiella pneumoniae , Estudos Retrospectivos , Fatores de Risco , Centros de Atenção Terciária
10.
Nat Cell Biol ; 26(2): 263-277, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38238450

RESUMO

Human in vitro fertilized embryos exhibit low developmental capabilities, and the mechanisms that underlie embryonic arrest remain unclear. Here using a single-cell multi-omics sequencing approach, we simultaneously analysed alterations in the transcriptome, chromatin accessibility and the DNA methylome in human embryonic arrest due to unexplained reasons. Arrested embryos displayed transcriptome disorders, including a distorted microtubule cytoskeleton, increased genomic instability and impaired glycolysis, which were coordinated with multiple epigenetic reprogramming defects. We identified Aurora A kinase (AURKA) repression as a cause of embryonic arrest. Mechanistically, arrested embryos induced through AURKA inhibition resembled the reprogramming abnormalities of natural embryonic arrest in terms of the transcriptome, the DNA methylome, chromatin accessibility and H3K4me3 modifications. Mitosis-independent sequential activation of the zygotic genome in arrested embryos showed that YY1 contributed to human major zygotic genome activation. Collectively, our study decodes the reprogramming abnormalities and mechanisms of human embryonic arrest and the key regulators of zygotic genome activation.


Assuntos
Aurora Quinase A , Multiômica , Humanos , Aurora Quinase A/genética , Blastocisto , Cromatina/genética , Citoesqueleto , Desenvolvimento Embrionário/genética
11.
Curr Med Imaging ; 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37691202

RESUMO

AIMS: This study aimed to develop a method for predicting short-term outcomes of lung cancer patients treated with intensity-modulated radiotherapy (IMRT) using radiomic features detected through computed tomography images. METHOD: A prediction model was developed based on a dataset of radiomic features obtained from 132 patients with lung cancer receiving IMRT. Dimension reduction was performed for the features using the maximum-relevance and minimum-redundancy (mRMR) algorithm, and the least absolute shrinkage and selection operator (LASSO) regression model was utilized to optimize feature selection for the IMRT-sensitivity prediction model. The model was constructed using binary logistic regression analysis and was evaluated using the concordance index (C-index), calibration plots, receiver operating characteristic curve, and decision curve analysis. RESULTS: Fifty features were selected from 1348 radiomic features using the mRMR method. Of these, three radiomic features were selected by LASSO logistic regression to construct the radiomics nomogram. The C-index of the model was 0.776 (95% confidence interval: 0.689-0.862) and 0.791 (95% confidence interval: 0.607-0.974) in the training and validation cohorts, respectively. Decision curve analysis showed that the radiomics nomogram was clinically useful. CONCLUSION: Radiomic features have the potential to be applied to predict the short-term efficacy of IMRT in patients with inoperable lung cancer.

12.
Phys Med ; 82: 109-113, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33610005

RESUMO

PURPOSE: It was given that the characteristics of the fluence distribution and the energy spectrum structure of 4MV photons on the Phase Space (PhSp) plane and a method to analyzing the characteristics. METHODS: After the PhSp file of 4 MV photons was acquired by the method of Monte Carlo (MC) calculation, the photons recorded by PhSp file were grouped based on the energy bin, and it was analyzed that the spatial distribution and energy spectrum structure of the photons. The photons in each energy group were continually grouped to sub-files according to momentum bin, and the primary and scattered photons could be separated according to the character of the fluence distribution of the photons in the sub-files. RESULTS: The energy of 4 MV beam is a continuous spectrum. The energy constituent on a pixel at different distances from the center point is different, and the average energy on the center axis of the field is the highest; The photons with 0-1.0 MeV had 42.6% of all; that with energy more than 3.0 MeV had 11.7%; greater than 4 MeV, just 1.5%. The primary and scattered photons were easy collected according to the distribution characteristics of sub-groups. CONCLUSIONS: The work to acquire and analyze the PhSp file of the 4 MV beam is significant. 4 MV, 6 MV, 8 MV, 10 MV and 15 MV energy beams basically cover the beams of radiotherapy, and a database of the energy beams could be built for the MC related research of other scholars.


Assuntos
Aceleradores de Partículas , Fótons , Bases de Dados Factuais , Método de Monte Carlo , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
13.
J Healthc Eng ; 2021: 1535046, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745489

RESUMO

Objective: This research aimed to explore the application of a mathematical model based on deep learning in hospital infection control of novel coronavirus (COVID-19) pneumonia. Methods: First, the epidemic data of Beijing, China, were utilized to make a definite susceptible-infected-removed (SIR) model fitting to determine the estimated value of the COVID-19 removal intensity ß, which was then used to do a determined SIR model and a stochastic SIR model fitting for the hospital. In addition, the reasonable ß and γ estimates of the hospital were determined, and the spread of the epidemic in hospital was simulated, to discuss the impact of basal reproductive number changes, isolation, vaccination, and so forth on COVID-19. Results: There was a certain gap between the fitting of SIR to the remover and the actual data. The fitting of the number of infections was accurate. The growth rate of the number of infections decreased after measures, such as isolation, were taken. The effect of herd immunity was achieved after the overall immunity reached 70.9%. Conclusion: The SIR model based on deep learning and the stochastic SIR fitting model were accurate in judging the development trend of the epidemic, which can provide basis and reference for hospital epidemic infection control.


Assuntos
COVID-19 , Infecção Hospitalar , Aprendizado Profundo , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Humanos , Modelos Teóricos , SARS-CoV-2
14.
Biomed Res Int ; 2021: 2529171, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765676

RESUMO

OBJECTIVE: This study intends to analyze the data of fungemia in a large tertiary hospital from 2010 to 2019, and is aimed at understanding its epidemic characteristics and drug resistance. METHODS: The "Hospital Infection Real-Time Monitoring System" was used to retrieve the case information of patients who were hospitalized for more than 48 hours from 2010 to 2019. The questionnaire was designed to collect patients' basic information, infection situation, drug resistance, and other related information. Statistical software was used for analysis. RESULTS: The fungi detection rate was in the range of 0.19%~0.75% in ten years, the average rate was 0.29%, and the rate 0.2%~0.3% since 2013, which was lower than that from 2010 to 2012. Non-Candida albicans was the main fungus, accounting for 62.50%. The drug resistance of non-C. albicans was higher than that of C. albicans, among which C. glabrata had the highest resistance rate. Data analysis showed that the patients with more serious basic diseases, combined with infection of other sites, surgery, long hospital stay, combination of antibiotics, and invasive catheterization, were more likely to occur fungemia. CONCLUSION: We should pay more attention to the patients with high-risk factors of fungemia and focus on the drug resistance of non-C. albicans, choose the right antifungal drugs, so as to improve the level of diagnosis and treatment.


Assuntos
Infecção Hospitalar/epidemiologia , Fungemia/tratamento farmacológico , Fungemia/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , China/epidemiologia , Infecção Hospitalar/tratamento farmacológico , Farmacorresistência Fúngica/efeitos dos fármacos , Feminino , Fluconazol/uso terapêutico , Fungemia/microbiologia , Fungos/efeitos dos fármacos , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Fatores de Risco , Centros de Atenção Terciária
15.
Antimicrob Resist Infect Control ; 10(1): 1, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407871

RESUMO

BACKGROUND: This report describes an outbreak of 71 patients developed B. cepacia urinary tract infection (UTI) by contaminated single-use anesthetic gel. METHODS: Epidemiological investigation of patients with B. cepacia-positive urine or blood samples between March 19, 2018 and Novemeber 15, 2018 was conducted to identify the source of infection. Microbiological samples from hospital surfaces, endoscopes, disposable items, and the hands of staff were tested for B. cepacia contamination. Pulsed-field gel electrophoresis (PFGE) was used to compare homology in B. cepacia isolates. RESULTS: During the outbreak, nosocomial B. cepacia UTI was confirmed in 71 patients. Epidemiological investigation showed that 66 patients underwent invasive urological diagnosis and treatment, while the remaining five patients underwent bedside indwelling catheterization, with all patients exposed to single-use anesthetic gel. All batches of anesthetic gel were recalled and the outbreak abated. Overall, 155 samples were collected from environmental surfaces and disposable items, and B. cepacia contamination was confirmed in samples from one used cystoscope and three anesthetic gels from the same batch. PFGE showed homology between 17 out of 20 B. cepacia isolates from patients and three isolates from the contaminated anesthetic gel. All patients achieved cure. CONCLUSION: Contaminated single-use anesthetic gel was confirmed as the source of the B. cepacia outbreak, with infection occurring during invasive urological diagnostic and treatments. Thus, investigations of nosocomial outbreaks of B. cepacia infection should consider contamination of diagnostic and treatment items used in infected patients.


Assuntos
Anestésicos , Infecções por Burkholderia/tratamento farmacológico , Infecção Hospitalar/etiologia , Contaminação de Medicamentos , Infecções Urinárias/etiologia , Infecções por Burkholderia/etiologia , China , Infecção Hospitalar/tratamento farmacológico , Surtos de Doenças , Eletroforese em Gel de Campo Pulsado , Feminino , Géis , Hospitais de Ensino , Humanos , Controle de Infecções , Masculino , Pessoa de Meia-Idade , Polissacarídeos Bacterianos , Centros de Atenção Terciária , Infecções Urinárias/tratamento farmacológico
16.
Protein Expr Purif ; 72(1): 19-25, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20347985

RESUMO

Hydrophobins are small secreted proteins produced by filamentous fungi. Being amphipathic and self-assembling, hydrophobins have drawn great attention since their discovery. The increase of production can reduce the cost and open up several new applications of hydrophobins. We successfully expressed recombinant Class I hydrophobin HGFI (rHGFI) by using pPIC9 vector with an alcohol oxidase 1 promoter in Pichia pastoris. Tricine-SDS-PAGE and Western blotting demonstrated that rHGFI, an 8 kDa protein, was secreted into the culture medium. The culture conditions of the transformant strain were optimized by controlling the methanol concentration and induction time. Ultrafiltration and reverse-phase high performance liquid chromatography were used to perform a large-scale purification of rHGFI. A stable production of rHGFI around 86 mg/L was achieved after the two-step purification. X-ray photoelectron spectroscopy and water contact angle measurements indicated that the functional rHGFI could self-assemble on hydrophobic siliconized glass and Teflon as well as on hydrophilic mica surfaces. A methylthiazol tetrazolium assay showed that rHGFI film could facilitate human aortic smooth muscle cell proliferation due to its cytocompatibility.


Assuntos
Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Grifola/genética , Pichia/genética , Sobrevivência Celular , Células Cultivadas , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Expressão Gênica , Vetores Genéticos/genética , Grifola/química , Grifola/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Músculo Liso Vascular/citologia , Espectroscopia Fotoeletrônica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Ultrafiltração
17.
Curr Microbiol ; 61(4): 329-34, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20213102

RESUMO

The antibiotic nisin, produced by Lactococcus lactis subsp. lactis N8, offers an extensive commercial prospect as natural food preservatives. The nisin immunity of the L. lactis strains is regulated by a variety of mechanisms. In this study, we isolated a L. lactis L31 strain with increased nisin resistance from a mini-Mu transposon mutant pool of strain N8. The single Mu insertion in strain L31 was in the irpT gene with unknown function. By comparing the proteomic profiles of L. lactis L31 and its parental strain, we found that changes occurred in the synthesis of a protein involved in cell wall biosynthesis (RmlD). Strain L31 had 13.7% higher content of rhamnose in the cell wall than the N8 strain. Overexpression of RmlD involved in the synthesis of dTDP-L: -rhamnose in the nisin-sensitive MG1363 strain increased nisin resistance of the strain. The results indicate that these cellular proteins effected nisin resistance in L. lactis N8.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Genes Bacterianos , Lactococcus lactis/efeitos dos fármacos , Lactococcus lactis/genética , Nisina/metabolismo , Nisina/farmacologia , Antibacterianos/metabolismo , Proteínas de Bactérias/genética , Southern Blotting , Parede Celular/genética , Parede Celular/metabolismo , Parede Celular/ultraestrutura , Farmacorresistência Bacteriana/genética , Eletroforese em Gel Bidimensional , Expressão Gênica , Lipoproteínas/genética , Lipoproteínas/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Nisina/genética , Plasmídeos , Reação em Cadeia da Polimerase , Processamento de Proteína Pós-Traducional
18.
3 Biotech ; 10(6): 258, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32550099

RESUMO

In this study, we applied a series of genetic modifications to wild-type S. cerevisiae strain BY4741 to address the bottlenecks in the l-tyrosine pathway. A tyrosine ammonia-lyase (TAL) gene from Rhodobacter capsulatus, which can catalyze conversion of l-tyrosine into p-coumaric acid, was overexpressed to facilitate the analysis of l-tyrosine and test the strain's capability to synthesize heterologous derivatives. First, we enhanced the supply of precursors by overexpressing transaldolase gene TAL1, enolase II gene ENO2, and pentafunctional enzyme gene ARO1 resulting in a 1.55-fold increase in p-coumaric acid production. Second, feedback inhibition of 3-deoxy-d-arabino-heptulosonate-7-phosphate synthase and chorismate mutase was relieved by overexpressing the mutated feedback-resistant ARO4 K229L and ARO7 G141S , and a 3.61-fold improvement of p-coumaric acid production was obtained. Finally, formation of byproducts was decreased by deleting pyruvate decarboxylase gene PDC5 and phenylpyruvate decarboxylase gene ARO10, and p-coumaric acid production was increased 2.52-fold. The best producer-when TAL1, ENO2, ARO1, ARO4 K229L , ARO7 G141S , and TAL were overexpressed, and PDC5 and ARO10 were deleted-increased p-coumaric acid production by 14.08-fold (from 1.4 to 19.71 mg L-1). Our study provided a valuable insight into the optimization of l-tyrosine metabolic pathway.

19.
Front Oncol ; 10: 554241, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33392067

RESUMO

BACKGROUND: To evaluate the dosimetric parameters of different bone marrow sparing strategies and radiotherapy technologies and determine the optimal strategy to reduce hematologic toxicity associated with concurrent chemoradiation (cCRT) for cervical cancer. METHODS: A total of 15 patients with Federation International of Gynecology and Obsterics (FIGO) Stage IIB cervical cancer treated with cCRT were re-planned for bone marrow (BM)-sparing plans. First, we determined the optimal BM sparing strategy for intensity modulated radiotherapy (IMRT), including a BMS-IMRT plan that used total BM sparing (IMRT-BM) as the dose-volume constraint, and another plan used os coxae (OC) and lumbosacral spine (LS) sparing (IMRT-LS+OC) to compare the plan without BM-sparing (IMRT-N). Then, we determined the optimal technology for the BMS-IMRT, including fixed-field IMRT (FF-IMRT), volumetric-modulated arc therapy (VMAT), and helical tomotherapy (HT). The conformity and homogeneity of PTV, exposure volume of OARs, and efficiency of radiation delivery were analyzed. RESULTS: Compared with the IMRT-N group, the average volume of BM that received ≥10, ≥20, ≥30, and ≥40 Gy decreased significantly in both two BM-sparing groups, especially in the IMRT-LS+OC group, meanwhile, two BMS-IMRT plans exhibited the similar effect on PTV coverage and other organs at risk (OARs) sparing. Among three common IMRT techniques in clinic, HT was significantly less effective than VMAT and FF-IMRT in the aspect of BM-Sparing. Additionally, VMAT exhibited more efficient radiation delivery. CONCLUSION: We recommend the use of VMAT with OC and LS as separate dose-volume constraints in cervical cancer patients aiming at reducing hematologic toxicity associated with cCRT, especially in developing countries.

20.
Biomed Res Int ; 2019: 8190475, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781645

RESUMO

BACKGROUND: Interventional therapy has been widely used in the medical field as its advantages of minimally invasive, safe and quick recovery. Bloodstream infection (BSI) is the most common healthcare-associated infections (HAIs) after interventional therapy, but there are few reports about it. This study intends to analyze the clinical characteristics and relevant factors of BSI after six years of interventional therapy in a large tertiary teaching hospital, in order to provide guidances for the prevention and control of BSI after interventional operations. METHODS: The case information of patients with BSI after interventional therapy from 2013 to 2018 were collected through the "real-time monitoring system of healthcare-associated infections". All BSI was determined by the infection control full-time staff and clinicians. Questionnaires were designed to review case by case and register the relevant patient information into a database. A total of 18 relevant factors were counted. Statistical software was used for analysis. RESULTS: 174 cases of BSI occurred in 25401 patients, the incidence was 0.69%, and BSI accounted for 50% of all infected sites. Gram-positive bacteria accounted for 56.05%, coagulase-negative Staphylococcus was the main infectious bacteria. Relevant risk factor analysis showed that hepatocellular carcinoma, had undergone surgery, biliary complications, prophylactic antibiotic, replacement of antibiotics, number of interventional operations, days of prophylactic antibiotic use were the related risk factors associated with BSI (P < 0.05). Multivariate analysis showed that days of prophylactic antibiotic use (OR = 1.586, P < 0.05) and replacement of antibiotics (OR = 13.349, P < 0.05) were the main risk factors associated with the development of BSI. CONCLUSIONS: BSI is the main infection site after interventional surgery. For patients with the risk factors as hepatocellular carcinoma/biliary complications/had undergone surgery etc., the time of prophylactic antibiotic use can be prolonged properly before interventional surgery, and selection of single antibiotic appropriate for use could significantly aid preventive measures to avoid occurrence of BSI.


Assuntos
Bacteriemia/tratamento farmacológico , Infecção Hospitalar/tratamento farmacológico , Hospitais de Ensino , Fatores de Risco , Centros de Atenção Terciária , Adulto , Idoso , Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Bacteriemia/microbiologia , Bacteriemia/prevenção & controle , Carcinoma Hepatocelular/complicações , China , Infecção Hospitalar/microbiologia , Feminino , Cirurgia Geral , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/patogenicidade , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/patogenicidade , Humanos , Incidência , Controle de Infecções , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Software
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