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1.
J Antimicrob Chemother ; 79(6): 1309-1312, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38564262

RESUMO

OBJECTIVES: To evaluate the performance of an in-house developed disk diffusion method for aztreonam in combination with avibactam against Enterobacteriales. METHODS: The in vitro antibacterial activity of aztreonam with avibactam against 204 carbapenemase-producing Enterobacteriales was determined by a disk diffusion method, with a broth microdilution method as a reference. RESULTS: The optimal S/R breakpoints for disk diffusion tests of 30/20 and 10/4 µg disks, calculated by the dBETs software using the model-based approaches, were ≥22/≤21 and ≥12/≤11 mm, respectively. On the basis of the estimated breakpoints, the CAs for disk diffusion tests of 30/20 and 10/4 µg aztreonam/avibactam disks were both 98.0%, with 0.5% major error and 37.5% very major error. CONCLUSIONS: The home-made disk diffusion method is an economical and practical method for clinical microbiology laboratories to determine the antibacterial susceptibility of aztreonam with avibactam against Enterobacteriales.


Assuntos
Antibacterianos , Compostos Azabicíclicos , Aztreonam , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Enterobacteriaceae , Aztreonam/farmacologia , Compostos Azabicíclicos/farmacologia , Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/métodos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/normas , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/normas , Humanos
2.
Artigo em Inglês | MEDLINE | ID: mdl-38970691

RESUMO

To evaluate the in vitro activity of ampicillin-sulbactam and cefoperazone-sulbactam against A. baumannii using the broth disk elution testing, a total of 150 A. baumannii isolates were collected from across China between January 2019 and January 2021, including 51 carbapenem-susceptible and 99 carbapenem-resistant isolates. Broth disk elution (BDE) and the broth microdilution (BMD) method were performed for all strains. The concentration range of the BDE was 10/10 µg/mL, 20/20 µg/mL, and 30/30 µg/mL for ampicillin-sulbactam, and 37.5/15 µg/mL, 75/30 µg/mL, 112.5/45 µg/mL, and 150/60 µg/mL for cefoperazone-sulbactam, respectively. Compared with BMD, the BDE results of ampicillin-sulbactam and cefoperazone-sulbactam showed a categorical agreement of 83.3% (125/150) and 95.3% (143/150), with minor errors of 16.7% (25/150) and 4.7% (7/150), respectively. No major error or very major errors were detected. The sensitivity differences by BDE of carbapenem-resistant A. baumannii (CRAb) to different concentrations of ampicillin-sulbactam showed statistically significant (p < 0.017), while those to cefoperazone-sulbactam at 37.5/15 µg/mL, 75/30 µg/mL, and 112.5/45 µg/mL were significant (p < 0.008). However, no significant difference in sensitivity was observed between 112.5/45 µg/mL and 150/60 µg/mL (p > 0.008). In conclusion, the BDE is a reliable and convenient method to detect the in vitro activity of cefoperazone-sulbactam against A. baumannii, and the results could serve as a clinical reference value when deciding whether or not to use high-dose sulbactam for the treatment of A. baumannii infections.

3.
Eur J Clin Microbiol Infect Dis ; 42(4): 525-528, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36847927

RESUMO

To investigate the antibiotic resistance and resistance mechanism of Corynebacterium kroppenstedtii (C. kroppenstedtii) isolated from patients with mastadenitis. Ninety C. kroppenstedtii clinical isolates were obtained from clinical specimens in 2018-2019. Species identification was performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antimicrobial susceptibility testing was performed by the broth microdilution method. The resistance genes were detected using PCR and DNA sequencing. The results of antimicrobial susceptibility testing indicated that the resistance rates of C. kroppenstedtii to erythromycin and clindamycin, ciprofloxacin, tetracycline, and trimethoprim-sulfamethoxazole were 88.9%, 88.9%, 67.8%, 62.2%, and 46.6%, respectively. None of the C. kroppenstedtii isolates was resistant to rifampicin, linezolid, vancomycin, or gentamicin. The gene of erm(X) was detected in all clindamycin and erythromycin-resistant strains. The gene of sul(1) and tet(W) were detected among all trimethoprim sulfamethoxazole-resistant strains and tetracycline-resistant strains, respectively. Furthermore, 1 or 2 amino acid mutations (mainly single mutation) were observed in the gyrA gene among ciprofloxacin-resistant strains.


Assuntos
Antibacterianos , Clindamicina , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Eritromicina , Tetraciclina , Ciprofloxacina/farmacologia , Combinação Trimetoprima e Sulfametoxazol , Resistência Microbiana a Medicamentos , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana
4.
Med Sci Monit ; 29: e939485, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37259486

RESUMO

BACKGROUND The COVID-19 pandemic has caused varying degrees of psychological stress among medical students. This research explored the post-traumatic stress symptoms (PTSS) of medical students in China and their relationship with positive coping and social support. MATERIAL AND METHODS In the form of cross-sectional online survey, 2280 medical students locked down at home were selected by random cluster method to investigate social support, coping style, and PTSS using the Social Support Rating Scale (SSRS), Simplified Coping Style Questionnaire (SCSQ), and Post-traumatic Stress Disorder (PTSD) Checklist-Civilian Version (PCL-C), respectively. RESULTS This research found that the PTSS detection rate in medical students was 10.42% during the COVID-19 pandemic. The PTSS scores of females were significantly higher than that of the males. However, the PTSS detection rate in females (9.71%) was not significantly different from that in males (11.24%). Compared with those of the non-PTSS group, the total score and its all-factor score of social support, the total score of coping style and the positive coping score of the PTSS group were much lower, while the negative coping score of the PTSS group was much higher (P<0.01). Positive coping was positively correlated with social support, while positive coping and social support were negatively correlated with PTSS. The total effect of positive coping on PTSS was -0.310 (P<0.001), the direct effect was -0.128 (P<0.01), and the indirect effect was -0.182 (P<0.001). Social support played a mediating role between positive coping and PTSS, with the mediating effect accounting for 58.81% of the total effect. CONCLUSIONS Social support plays a mediating role between positive coping and post-traumatic stress symptoms. Objective support and positive coping are the 2 main protective factors of PTSS.


Assuntos
COVID-19 , Transtornos de Estresse Pós-Traumáticos , Estudantes de Medicina , Masculino , Feminino , Humanos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/etiologia , COVID-19/complicações , Estudos Transversais , Pandemias , Adaptação Psicológica , Apoio Social , Inquéritos e Questionários , China/epidemiologia
5.
BMC Womens Health ; 23(1): 388, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491234

RESUMO

BACKGROUND: Increasing evidence has suggested that Corynebacterium kroppenstedtii is associated with some cases of granulomatous mastitis, mostly based on pathology or microbiology. We aimed to identify the clinical characteristics and treatment regimens for granulomatous mastitis with Corynebacterium kroppenstedtii infection. Understanding these clinical features is essential for patient care. METHODS: We retrospectively collected data on 201 patients who were pathologically diagnosed with granulomatous mastitis and had microbiological results of either Corynebacterium kroppenstedtii or no bacterial growth and recorded and analysed their demographics, clinical characteristics, and clinical outcomes. RESULTS: There were 107 patients in the CK group and 94 patients in the negative group. Sinus formation (x2 = 13.028, p = 0.000), time to complete remission at the first treatment period (Z = -3.027, p = 0.002), diameter of breast mass at first-time medical consultancy (Z = -2.539, p = 0.011) and recurrence (x2 = 4.953, p = 0.026) were statistically significant. Age (Z = -1.046, p = 0.295), laterality (x2 = 4.217, p = 0.121), time to presentation since the last delivery (x2 = 0.028, p = 0.868), BMI (Z = -0.947, p = 0.344), lactation time (Z = -1.378, p = 0.168), parity (x2 = 1.799, p = 0.180), gravida (Z = -0.144, p = 0.885), history of lactational mastitis or abscess (x2 = 0.115, p = 0.734), local trauma (x2 = 0.982, p = 0.322), hyperprolactinemia (x2 = 0.706, p = 0.401), erythema nodosum (x2 = 0.292, p = 0.589), and nipple discharge (x2 = 0.281, p = 0.596) did not demonstrate statistical significance. Regarding recurrence related to therapeutic strategy, except for surgery combined with immunosuppressants (x2 = 9.110, p = 0.003), which was statistically significant, none of the other treatment regimens reached statistical significance. The recurrence rate of patients in the CK group using rifampicin in their treatment course was 22.0% (x2 = 4.892, p = 0.027). CONCLUSIONS: Granulomatous mastitis accompanied by Corynebacterium kroppenstedtii more easily forms sinuses and has a higher recurrence rate. Both of the clinical characteristics may indicate that Corynebacterium kroppenstedtii plays an important role in the development and progression of granulomatous mastitis. Lipophilic antibiotics may be essential for granulomatous mastitis with Corynebacterium kroppenstedtii infection.


Assuntos
Infecções por Corynebacterium , Mastite Granulomatosa , Feminino , Humanos , Corynebacterium , Infecções por Corynebacterium/complicações , Infecções por Corynebacterium/tratamento farmacológico , Infecções por Corynebacterium/diagnóstico , Mastite Granulomatosa/complicações , Mastite Granulomatosa/tratamento farmacológico , Estudos Retrospectivos , Adulto , Pessoa de Meia-Idade
6.
Bull Environ Contam Toxicol ; 109(3): 548-555, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35689130

RESUMO

This study explored occurrence of phthalic acid esters (PAEs) in protected agriculture soils and assessed their potential health risks to humans. Results showed that DEHP and DBP were the most abundant PAEs congeners, with mean concentrations of 318.68 µg/kg and 137.56 µg/kg, respectively. DOP and BBP concentrations were relatively low, and DMP and DEP were not detected in all samples. DBP concentrations were higher than the allowable concentration standard value. Additionally, soil pH and organic matter were key environmental parameters which may play the vital roles to the occurrence of organic pollutants. Heath risk assessment results indicated that dermal contact was the predominant human exposure route under non-dietary conditions, and children obtained higher health risk scores than adults. In summary, the overall health risk scores were at an acceptable level. These results provide insights for assessing soil environmental safety and ecological risks in protected agricultural soil.


Assuntos
Ácidos Ftálicos , Poluentes do Solo , Agricultura/métodos , Criança , China , Dibutilftalato , Ésteres , Humanos , Solo , Poluentes do Solo/análise
7.
Can J Infect Dis Med Microbiol ; 2022: 1181283, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35368516

RESUMO

By studying the distribution and drug resistance of bacterial pathogens associated with lower respiratory tract infection (LRTI) in children in Chengdu and the effect of the COVID-19 on the distribution of pathogens and by analyzing the epidemic trend and drug resistance changes of the main pathogens of LRTI, this research is supposed to provide a useful basis for the prevention of LRTI in children and the rational use of drugs in clinical practice. Hospitalized children clinically diagnosed with LRTI in Chengdu Women and Children's Central Hospital from 2011 to 2020 were selected as the study subjects. The pathogens of LRTI in children and the distribution of pathogens in different ages, genders, seasons, years, and departments and before and after the pandemic situation of COVID-19 were counted. The drug resistance distribution of the top six pathogens with the highest infection rate in the past three years and the trend of drug resistance in the past decade were analyzed. A total of 26,469 pathogens were isolated. Among them, 6240 strains (23.6%) were Gram-positive bacteria, 20152 strains (76.1%) were Gram-negative bacteria, and 73 strains (0.3%) were fungi. Klebsiella pneumoniae, Escherichia coli, Enterobacter cloacae, and Staphylococcus aureus were highly isolated in the group of infants aged 0-1 (P < 0.01), Moraxella catarrhalis and Streptococcus pneumoniae were highly isolated in children aged 1-6 (P < 0.01), and Haemophilus influenzae was highly isolated in children over 1 (P < 0.01). The isolation rates of Enterobacteriaceae, Acinetobacter baumannii, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Staphylococcus aureus, and Candida albicans in the lower respiratory tract of 0-1 year-old male infants were higher than those of female infants (p < 0.05). Haemophilus influenzae was highly isolated in spring and summer, and Moraxella catarrhalis was highly isolated in autumn and winter, while the infection of Streptococcus pneumoniae was mainly concentrated in winter. This difference was statistically significant (P < 0.01). Affected by the COVID-19 pandemic, the isolation rates of Haemophilus influenzae and Streptococcus pneumoniae were significantly lower than those before the pandemic, and the isolation rate of Moraxella catarrhalis was significantly higher. The difference was statistically significant (P < 0.01). The proportion of isolated negative bacteria in NICU and PICU was higher than that in positive bacteria, and the infection rates of Klebsiella pneumoniae, Escherichia coli, Enterobacter cloacae, and Acinetobacter baumannii were higher than those in other departments. The differences were statistically significant (P < 0.01). The results of drug sensitivity test showed that the drug resistance of Haemophilus influenzae and Moraxella catarrhalis was mainly concentrated in Ampicillin, First- and Second-generation cephalosporins, and Cotrimoxazole, with stable sensitivity to Third-generation cephalosporins, while the drug resistance of Streptococcus pneumoniae was concentrated in Macrolides, Sulfonamides, and Tetracyclines, with stable sensitivity to Penicillin. Staphylococcus aureus is highly resistant to penicillins and macrolides and susceptible to vancomycin. Enterobacteriaceae resistance is concentrated in cephalosporins, with a low rate of carbapenem resistance. From 2018 to 2020, 1557 strains of Staphylococcus aureus were isolated, of which 416 strains were MRSA, accounting for 27% of the isolates; 1064 strains of Escherichia coli were isolated, of which 423 strains were ESBL and 23 strains were CRE, accounting for 40% and 2% of the isolates, respectively; and 1400 strains of Klebsiella pneumoniae were isolated, of which 385 strains were ESBL and 402 strains were CRE, accounting for 28% and 29% of the isolates, respectively. Since 2011, the resistance of Escherichia coli and Klebsiella pneumoniae to Third-generation cephalosporins has increased, peaking in 2017, and has decreased after 2018, years after which carbapenem resistance has increased significantly, corresponding to an increase in the detection rate of Carbapenem-resistant Enterobacteriaceae CRE. Findings from this study revealed that there are significant differences in community-associated infectious pathogens before and after the COVID-19 pandemic, and there are significant age differences, seasonal epidemic trends, and high departmental correlation of pathogens related to lower respiratory tract disease infection in children. There was a significant gender difference in the isolation rate of pathogens associated with LRTI in infants under one year. Vaccination, implementation of isolation measures and social distance, strengthening of personal protective measures, aseptic operation of invasive medical treatment, hand hygiene, and environmental disinfection are beneficial to reducing community-associated pathogen infection, opportunistic pathogen infection, and an increase in resistant bacteria. The strengthening of bacterial culture of lower respiratory tract samples by pediatricians is conducive to the diagnosis of respiratory tract infections caused by different pathogens, contributing to the selection of effective drugs for treatment according to drug susceptibility results, which is important for the rational use of antibiotics and curbing bacterial resistance.

8.
Clin Lab ; 66(6)2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32538042

RESUMO

BACKGROUND: As the mechanism of systemic inflammatory response in the course of cancer progression is gradually revealed, research has begun to focus on the two indictors of neutrophil to lymphocyte ratio (NLR) and the platelet to lymphocyte ratio (PLR) which may be associated with clinical disease development, treatment, and prognosis in patients who are undergoing surgery, chemotherapy, targeted therapy, and immunotherapy. We aim to define the clinical application values of those two biomarkers in multiple cancers. METHODS: PubMed and Web of Science are used to perform the systematic literature research. Related articles and references were identified for analyzing the association of between NLR and PLR with treatment outcome, as well as progression of cancers. RESULTS: NLR and PLR are convenient, easy to calculate, economical, and practical biomarkers, effectively predicting treatment outcome and risk of death based on inflammatory cells. Elevated NLR and PLR are significantly in line with worse clinical pathological characteristics, deeper invasiveness, more lymph node metastasis and advanced TNM stage. A significant association was observed that high NLR and PLR predict poor overall survival and disease-free survival. CONCLUSIONS: NLR and PLR can be used as available biomarkers in prognostic survival and formulation of treatment strategy of multiple cancers.


Assuntos
Contagem de Células Sanguíneas/métodos , Plaquetas , Linfócitos , Neoplasias , Neutrófilos , Humanos , Neoplasias/sangue , Neoplasias/diagnóstico , Prognóstico , Curva ROC
9.
Bull Environ Contam Toxicol ; 104(2): 301-306, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31784767

RESUMO

An ultrasonic-assisted extraction methodology coupled with gas chromatography-mass spectrometer analytical technique was used to determine concentration of phthalic acid esters (PAEs) in typical greenhouse soil. The results showed that the developed method has a reliable recovery rate (80.78%-112.89%) and a low detection limit (10- 4 mg/kg) which met the requirements of residue determination. The analysis of 32 soil samples revealed that except for dimethyl phthalate, the concentration of other five PAEs was detected and followed the sequence di-(2-ethylhcxyl) phthalate > dibutyl phthalate > di-n-octyl phthalate > butylbenz phthalate > diethyl phthalate. Σ6PAEs concentrations ranged from 136.91 to 1121.74 µg/kg (mean 319.59 µg/kg). PAEs was closely correlated with soil pH and organic matter, but not with cultivation ages which indicates that the increase of cultivation age is not the main reason for the change of soil PAEs concentration.


Assuntos
Ésteres/análise , Ácidos Ftálicos/análise , Poluentes do Solo/análise , Monitoramento Ambiental , Ésteres/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Concentração de Íons de Hidrogênio , Limite de Detecção , Compostos Orgânicos/análise , Ácidos Ftálicos/química , Solo/química , Poluentes do Solo/química
10.
Bull Environ Contam Toxicol ; 104(6): 820-827, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32424434

RESUMO

Di-(2-ethylhcxyl) phthalate (DEHP) is applied as plasticizer, which results in the pollution of environment. In this study, the effects of DEHP on soil microbial functions, structure and genetic diversity were investigated. The concentration of DEHP in the soil were 0, 0.1, 1, 10 and 50 mg/kg, and the experimental period were 28 days. DEHP reduced the quantity, abundance, species dominance and homogeneity of soil microbes during the first 14 days. In addition, microbial utilization efficiency of carbon (carbohydrates, aliphatics, amino acids, metabolites) was impacted after 28 days, though the effects gradually weakened. Based on denaturing gradient gel electrophoresis and clone library analysis, in the presence of DEHP, the dominant microbes in the DEHP-contaminated soil were Sphingomonas and Bacillus, which belonged to the Acidobacteria and Proteobacteriav, respectively. With 0.1 or 1 mg/kg of DEHP, the relative abundances of Acidobacteria were higher, and with 10 or 50 mg/kg of DEHP, the relative abundances of Proteobacteria were higher.


Assuntos
Dietilexilftalato/toxicidade , Microbiota/efeitos dos fármacos , Plastificantes/toxicidade , Microbiologia do Solo , Poluentes do Solo/toxicidade , Solo/química , Bacillus/efeitos dos fármacos , Bacillus/metabolismo , Carbono/metabolismo , Dietilexilftalato/análise , Plastificantes/análise , Poluentes do Solo/análise , Sphingomonas/efeitos dos fármacos , Sphingomonas/metabolismo
11.
Bull Environ Contam Toxicol ; 105(1): 1, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32561950

RESUMO

In the original publication of the article, there was an error in the abstract section. The incorrect sentence "the dominant microbes in the DEHP-contaminated soil were Sphingomonas and Bacillus, which belonged to the Acidobacteria and Proteobacteriav, respectively" should be revised to "the dominant microbes in the DEHP-contaminated soil were belonged to the Acidobacteria and Proteobacteria, respectively." This has been corrected with this erratum.

12.
Ecotoxicol Environ Saf ; 166: 237-241, 2018 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-30273846

RESUMO

In recent years, increasing efforts have focused on production of organic-inorganic compound fertilizers using ammonium sulfite pulping waste liquor. However, their ecological effects on soil have not been studied. In this study, earthworm Eisenia fetida was exposed to various doses (0, 0.13, 0.26 and 0.52 kg/m2) for different time (7, 14, 21, and 28 d) to evaluate the effects of fertilizers made from pulping waste liquor, including reactive oxygen species (ROS) generation, antioxidant enzymes activities, glutathione S-transferase enzyme (GST) activity, malondialdehyde (MDA) content and DNA damage. Results showed that there were significant increase of ROS and MDA levels after 14 d, inducing production of antioxidant enzymes (superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT)) as well as GST. Before 14 d, excess ROS and MDA caused damage to the DNA of earthworms, leading to gradual increase of Olive tail moment (OTM) in the comet assay. With the exposure time extended to 28 d, owing to the combined effects of elimination of free radicals by antioxidant enzymes and detoxification enzymes as well as self-repairing function of cells, ROS and MDA levels declined slightly and OTM gradually decreased. In summary, this study indicated that there was a toxicological effect on earthworms when fertilizers made from pulping waste liquor were applied to soil, which needs more attention.


Assuntos
Fertilizantes/toxicidade , Resíduos Industriais/efeitos adversos , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Animais , Antioxidantes/metabolismo , Catalase/genética , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Ecotoxicologia , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Papel , Peroxidase/genética , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
13.
Ecotoxicol Environ Saf ; 159: 317-323, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29775827

RESUMO

The bioremediation of soil contaminated with organic pesticides is a safe and effective approach to remove pollutants from the soil. However, whether the invasion of foreign aid organisms affects the local organisms has received increasing attention in recent years. Therefore, the purpose of this study was to examine the degradation ability of atrazine by the strain HB-5 and evaluate its effects on natural bacterial communities in a miniature pot experiment. Results showed that HB-5 accelerated the degradation of atrazine and the degradation half-life of atrazine was 3.3 times less than the natural soil. Additionally, HB-5 increased the quantities of indigenous bacteria, the microbial biomass carbon and the Shannon, Simpson and McIntosh diversity indices of soil microbes in its early stage of use, But these parameters in soil treated with HB-5 decreased to values as low as those found in the control at the later stage of incubation. These suggested that the bacteria vanished as atrazine was completely removed. These results demonstrated that Arthrobacter sp. strain HB-5 had great potential and would be an effective and environmental friendly technique to remove atrazine from the contaminated soil.


Assuntos
Arthrobacter/metabolismo , Atrazina/metabolismo , Herbicidas/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Carbono/metabolismo
14.
J Environ Manage ; 228: 336-345, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30241039

RESUMO

In order to intuitively and clearly evaluate the potential and current distribution, the fluid flow and mixing, as well as mass transfer involved in electrocoagulation process for As and Sb removal, numerical simulation of electric field, flow field and mass transfer were constructed by Comsol Multiphysics and verified by experiments. Results displayed that the primary current and potential distribution were improved by changing electrode distance or adding insulator in a batch reactor. When configuration 2 and 2 cm electrode distance were applied, a more uniform primary current distribution and higher electrode current efficiency were obtained. In a continuous flow reactor, the increase of flow rate resulted in the left shift of the peak in residence time distribution curve, gradual decrease of the tailing area, reduction of the stagnation zone, and more uniform mixing of the fluid. However, higher than 0.043 L/min was unfavorable to the formation of flocs and its effective combination with pollutants. According to the simulation of mass transfer, at the initial stage, the rate of electrolysis/hydrolysis was greater than that of mass transfer. Fe2+, OH-, and Fe(OH)2 were primarily concentrated on the anode, cathode, and between the two electrodes, respectively. Under the action of electromigration, diffusion and convection, the concentration distribution of Fe(OH)2 increased at the direction of streamline. The concentration of Fe2+ and OH- achieved the minimum value at the outlet. However, Fe(OH)+ concentration and distribution were hardly affected by the treatment time, and once generated, immediately proceed to the next hydrolysis reaction.


Assuntos
Antimônio/isolamento & purificação , Arsênio/isolamento & purificação , Eletrocoagulação/métodos , Eletrodos , Eletrólise
15.
Electrophoresis ; 37(14): 2050-3, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27120411

RESUMO

In this work, we introduce electrospinning to prepare magnetic enantioselective material for the first time. Multianalytical tools were used to characterize the resulted magnetic cellulose tris-(4-methylbenzoate) particles including transmission electron microscopy, SEM, FTIR spectroscopy, thermogravimetric analysis, X-ray diffractometer. Under the optimum conditions, the resulted particles were well-shaped sphere with a diameter range of 800 nm to 2 µm and high magnetic sensitivity. The enantioselectivity of the adsorbents was evaluated using racemic ibuprofen as a model drug; an e.e. value of -4.78% (where e.e. is enantiomeric excess) was achieved in a single adsorption stage. We hope that our finding provides an efficient and economical procedure for the preparation of magnetic enantioselective materials with high selectivity and reproducibility.


Assuntos
Benzoatos/química , Celulose/química , Magnetismo , Adsorção , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Estereoisomerismo , Termogravimetria , Difração de Raios X
16.
Rapid Commun Mass Spectrom ; 30 Suppl 1: 190-5, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27539437

RESUMO

RATIONALE: Selective enrichment of glycopeptides prior to mass spectrometry (MS) analysis is essential due to the low abundance of the modified glycopeptides in complex samples, ion suppression effects during MS ionization and detection caused by the co-presence of non-glycosylated peptides, etc. Among different enrichment approaches, hydrophilic interaction liquid chromatography (HILIC)-based magnetic separation has become one of the most popular methods in recent years, due to its high efficiency and selectivity for glycopeptide enrichment. METHODS: Herein, novel carboxymethyl-ß-cyclodextrin (CMCD)-modified magnetic nanoparticles (MNPs) were synthesized via a carbodiimide activation method. CMCD was covalently bonded with the -OH group on the surface of MNPs through carbodiimide, and the proposed procedure provides a rapid and efficient alternative for glycopeptide enrichment due to its stable interaction, time-saving, and easy operation. RESULTS: The prepared absorbents with a mean diameter of 15 nm demonstrated a strong magnetic response to an externally applied magnetic field. The results of thermogravimetric analysis showed the content of bound CMCD was 3 wt%. The outer CMCD layer conjugated on the Fe3 O4 core showed high hydrophilic surface property. In the analysis of a complex mouse liver sample, a total of 666 unique N-glycosylation sites corresponding to 494 glycosylated proteins were identified successfully. CONCLUSIONS: The study demonstrated an easy-to-use CMCD-modified MNPs-based approach with high selectivity and high capacity in the enrichment of low-abundance glycopeptides from complex biological samples. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Glicopeptídeos/química , Nanopartículas de Magnetita/química , beta-Ciclodextrinas/química , Animais , Carbodi-Imidas/química , Glicopeptídeos/análise , Fígado/química , Espectrometria de Massas/métodos , Camundongos , Propriedades de Superfície , beta-Ciclodextrinas/síntese química
17.
Med Sci Monit ; 22: 1663-72, 2016 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-27187589

RESUMO

BACKGROUND The usefulness of Des-g-carboxyprothrombin (DCP) has been indicated in areas where hepatitis C virus is prevalent. DCP has yet to be used in China. The aim of this study was to evaluate the usefulness of DCP in Chinese patients with hepatocellular carcinoma (HCC) predominantly caused by hepatitis B. MATERIAL AND METHODS 329 subjects with HCC and 371 subjects without HCC that all underwent surgery were consecutively enrolled. Serum AFP and plasma DCP levels in all subjects and 153 healthy volunteers were measured and analyzed. RESULTS Of 329 subjects with HCC, 258 (78.4%) were HBsAg positive. The median level of plasma DCP was 853.72 mAU/mL in subjects with HCC, 26.43 mAU/mL in subjects without HCC, and 29.91 m AU/mL in healthy volunteers. A cut-off DCP value of 87 mAU/mL yielded the optimal sensitivity of 74.80% and a specificity of 83.33% for differentiating subjects with HCC from subjects without HCC. The combination of AFP of 21.33 ng/mL and DCP of 87 mAU/mL had a sensitivity of 82.60% for tumors no larger than 2 cm, as well as a sensitivity of 90% for tumors larger than 5 cm. CONCLUSIONS The combination of DCP and AFP yielded great improvement in sensitivity in differentiating subjects with HCC from subjects without HCC. These two markers may be incorporated in the protocol for surveillance and diagnosis of HCC in the high-risk Chinese population.


Assuntos
Biomarcadores/sangue , Carcinoma Hepatocelular/sangue , Neoplasias Hepáticas/sangue , Precursores de Proteínas/sangue , Adulto , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/virologia , China , Feminino , Hepacivirus/isolamento & purificação , Hepatite C Crônica/sangue , Humanos , Técnicas Imunoenzimáticas , Cirrose Hepática/sangue , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Protrombina , alfa-Fetoproteínas/metabolismo
18.
Anal Chem ; 87(13): 6849-53, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26066908

RESUMO

In this work, a soft and nondestructive approach was developed to prepare concanavalin A-chelating magnetic nanoparticles (Con A-MNPs) for selective enrichment of glycoproteins. Ethylenediamine tetraacetic acid-modified-MNPs (EDTA-MNPs) were prepared by a one-pot chemical coprecipitation method first, and then, Cu(II) cations were used as bridge groups to immobilize Con A on EDTA-MNPs. The as-prepared absorbents with a mean diameter of 15 nm showed a strong magnetic response to an externally applied magnetic field. The results of thermogravimetric analysis showed the content of immobilized Con A was up to 28 wt %. For glycoprotein ovalbumin, the maximum capacity and equilibrium constant were 72.41 mg/g and 0.6035 L/mg, respectively. The as-prepared nanocomposites exhibited a remarkable selectivity for glycoproteins and can enrich glycoproteins specifically from a mixture of glycoprotein and nonglycoprotein even at a molar ratio of 1:600. It was also successfully applied for the enrichment of glycoproteins from real egg white samples. We expect that our finding will serve as a helpful template for others to design new adsorbents for enriching glycoproteins.


Assuntos
Quelantes/química , Concanavalina A/química , Glicoproteínas/química , Magnetismo , Nanopartículas
19.
Glob Health Med ; 6(3): 170-173, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38947413

RESUMO

The recent dramatic progress in systemic therapy for hepatocellular carcinoma (HCC) provides the possibility of a combination of surgery and systemic therapy including adjuvant, neoadjuvant, or conversion settings. Since the turn of the century, at least three negative studies have tested adjuvant therapies after curative resection or ablation, including uracil-tegafur, which is an oral chemotherapeutic drug, sorafenib, and peretinoin, which a synthetic retinoid that may induce the apoptosis and differentiation of liver cancer cells. Using more potent immuno-checkpoint inhibitors (ICIs), at least 4 phase III trials of adjuvant immunotherapy are ongoing: nivolumab, durvalumab/ bevacizumab, pembrolizumab, and atezolizumab+bevacizumab. Very recently, the last trial indicated a significantly better recurrence-free survival (RFS) for adjuvant atezolizumab+bevacizumab. Another promising combination of surgery and systemic therapy is neoadjuvant therapy for potentially resectable cases or a conversion strategy for oncologically unresectable cases. There are 2 neoadjuvant trials for technically or oncologically unresectable HCCs ongoing in Japan: the LENS-HCC trial using lenvatinib and the RACB study using atezolizumab+bevacizumab. A longer follow-up may be needed, but the overall survival (OS) in resected cases seems much higher than that in unresectable cases. Recently, the Japan Liver Cancer Association (JLCA) and the Japanese Society of HPB Surgery (JSHPBS) created a joint working group on "so-called borderline resectable HCC". They obtained a Japanese consensus on this issue that has been published on the websites of JLCA and JSHPBS. The definition of resectability or borderline resectability provides a common language regarding advanced HCC for investigators and is a useful tool for future clinical trials.

20.
Biosci Trends ; 18(1): 21-41, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38382930

RESUMO

Hepatocellular carcinoma (HCC), a challenging malignancy, often necessitates surgical intervention, notably liver resection. However, the high recurrence rate, reaching 70% within 5 years post-resection, significantly impacts patient outcomes. Neoadjuvant therapies aim to preoperatively address this challenge, reducing lesion size, improving surgical resection rates, deactivating potential micro-metastases, and ultimately lowering postoperative recurrence rates. This review concentrates on advances in research on and clinical use of neoadjuvant therapies for HCC, with particular attention to the use of immune checkpoint inhibitors (ICIs) targeting programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-L1), and cytotoxic T-lymphocyte-associated protein-4 (CTLA-4). Ongoing clinical studies exploring immunotherapy combined with a tyrosine kinase inhibitor (TKI), interventional therapy, radiotherapy, and other modalities offer promising insights into overcoming resistance to monotherapies. In summary, neoadjuvant therapies hold significant promise in terms of improving the prognosis for patients with HCC and enhancing long-term survival, particularly through innovative combination strategies.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Terapia Neoadjuvante , Imunoterapia
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