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1.
Environ Sci Technol ; 57(49): 20480-20493, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38015815

RESUMO

Studies about the impacts of maternal exposure to perchlorate, thiocyanate, and nitrate on offspring neurodevelopment are scarce. Based on a birth cohort in China, 1,028 mothers provided urine samples at three trimesters for determination of the three target analytes, and their offspring neurodevelopment was evaluated at 2 years old. Associations of maternal exposure to the three chemicals with offspring neurodevelopment were estimated using three statistical methods. Trimester-specific analyses using generalized estimating equation models showed that double increment of thiocyanate and nitrate during the first trimester was associated with 1.56 (95% CI: -2.82, -0.30) and 1.22 (-2.40, -0.03) point decreases in the offspring mental development index (MDI), respectively. Weighted quantile sum (WQS) regression analyses showed that the mixture exposure at the first and second trimesters was negatively associated with the offspring MDI (ß = -2.39, 95% CI: -3.85, -0.93; ß = -1.75, 95% CI: -3.04, -0.47, respectively) and thiocyanate contributed the most to the association (65.0 and 91.6%, respectively). Bayesian kernel machine regression analyses suggested an inverted U-shape relationship of maternal urinary thiocyanate with the offspring MDI. These findings suggested that prenatal exposure to the three chemicals (at current levels), especially thiocyanate and nitrate, may impair neurodevelopment. Early pregnancy seems to be the sensitive window.


Assuntos
Nitratos , Percloratos , Criança , Gravidez , Feminino , Humanos , Pré-Escolar , Nitratos/urina , Estudos de Coortes , Percloratos/urina , Tiocianatos/urina , Teorema de Bayes , Exposição Materna
2.
Clin Oral Investig ; 27(2): 751-758, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36571588

RESUMO

OBJECTIVE: The study aims to compare differences among iliac bone flaps with different iliac crest orientations for the repair of mandibular defects with an aim to analyze their advantages, disadvantages, and effects. MATERIAL AND METHODS: Clinical data and computed tomography scans of all patients who underwent iliac bone flap repair of the mandible in Peking University School and Hospital of Stomatology from January 2016 to April 2021 were collected. Patients were divided into the iliac crest towards alveolar process (Group A) and the iliac crest towards mandibular inferior margin (Group B). Software was used to measure corresponding indicators. The results obtained for the groups were statistically analyzed. RESULTS: The study included 78 patients (25 and 53 in groups A and B, respectively). The symmetry of the LC-type defect was better in group A (p < 0.05). The all-bone width of the alveolar process side in group A was greater than 6 mm; in 15 cases of group B, the width was less than 6 mm (p < 0.05). The intermaxillary distance of two sites were higher in group B (p < 0.05). The bone cortical thickness was significantly thicker in group A (p < 0.05). CONCLUSION: One year after the mandibular body defect was reconstructed with a vascularized iliac bone flap, the iliac crest towards alveolar process group showed better bone symmetry, width, intermaxillary distance, and cortical thickness to meet the planting requirements. CLINICAL RELEVANCE: The use of an iliac crest towards alveolar process may be a better approach for mandible reconstruction.


Assuntos
Mandíbula , Reconstrução Mandibular , Retalhos Cirúrgicos , Humanos , Transplante Ósseo/métodos , Ílio , Mandíbula/cirurgia , Neoplasias Mandibulares , Reconstrução Mandibular/métodos , Implantes Dentários
3.
Nano Lett ; 22(17): 6923-6929, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36006735

RESUMO

Excitons in two-dimensional (2D) materials have attracted the attention of the community to develop improved photoelectronic devices. Previous reports are based on direct excitation where the out-of-plane illumination projects a uniform single-mode light spot. However, because of the optical diffraction limit, the minimal spot size is a few micrometers, inhibiting the precise manipulation and control of excitons at the nanoscale level. Herein, we introduced the in-plane coherent surface plasmonic interference (SPI) field to excite and modulate excitons remotely. Compared to the out-of-plane light, a uniform in-plane SPI suggests a more compact spatial volume and an abundance of mode selections for a single or an array of device modulation. Our results not only build up a fundamental platform for operating and encoding the exciton states at the nanoscale level but also provide a new avenue toward all-optical integrated valleytronic chips for future quantum computation and information applications.

4.
Molecules ; 28(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37050033

RESUMO

This study evaluates the phenolic profile as well as the antioxidant properties of Shennongjia Apis cerana honey through a comparison with Apis mellifera honey in China. The total phenolic content (TPC) ranges from 263 ± 2 to 681 ± 36 mg gallic acid/kg. The total flavonoids content (TFC) ranges from 35.9 ± 0.4 to 102.2 ± 0.8 mg epicatechin/kg. The correlations between TPC or TFC and the antioxidant results (FRAP, DPPH, and ABTS) were found to be statistically significant (p < 0.01). Furthermore, the phenolic compounds are quantified and qualified by high performance liquid chromatography-high resolution mass spectrometry (HPLC-HRMS), and a total of 83 phenolic compounds were tentatively identified in this study. A metabolomics analysis based on the 83 polyphenols was carried out and subjected to principal component analysis and orthogonal partial least squares-discriminant analysis. The results showed that it was possible to distinguish Apis cerana honey from Apis mellifera honey based on the phenolic profile.


Assuntos
Mel , Abelhas , Animais , Mel/análise , Antioxidantes/farmacologia , Fenóis/análise , Flavonoides , China
5.
J Am Chem Soc ; 144(17): 7768-7777, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35417167

RESUMO

Approaching single-crystal-like morphology has always been important in driving materials toward their optimal properties. With only orientational order, liquid crystal (LC) materials require dual-axis orientational control to optimize their structural order in the bulk phase. However, current external guiding fields such as electrical, magnetic, and mechanical guiding fields are less effective in aligning amphiphilic LCs. In this study, water is developed as an excellent structural stabilizer and orientation-directing agent of an amphiphilic discotic molecule (AD) in the water-induced self-assembly (WISA) process. Thermal analysis and structural characterization results show that water increases the stability and domain sizes of the hexagonal columnar (Colh) phase of the AD by co-assembling with the ADs to form bulk artificial water channels (AWCs). Moreover, through control over the nucleation conditions (degree of supercooling and location of nucleation), dual-axis alignment in both the planar and vertical growth of the AWCs is achieved by applying water as the guiding field in the directional WISA. With precise control over the hierarchical structures, the bulk AWC array of the AD delivers excellent salt rejection properties and water permeability. Considering that all the amphiphilic LCs have hydrophilic segments, these new roles of water in the WISA process could launch the further development of functional amphiphilic LCs by providing a dynamic interaction and a readily available guiding field.


Assuntos
Aquaporinas , Cristais Líquidos , Interações Hidrofóbicas e Hidrofílicas , Cristais Líquidos/química , Cloreto de Sódio , Água/química
6.
Opt Express ; 30(21): 37637-37647, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36258348

RESUMO

We theoretically study the stability of mode-coupling-assisted frequency comb generation in normal-dispersion microresonators. With the aid of mode coupling, quantitative analysis of the modulational instability is explored in the parameter space of pump power and detuning. By exploring the coupled mode number, dispersion, and coupling strength in the normalized Lugiato-Lefever model, the modulational stability gain exists and yields extended spatial structures within the regime of eigenvalue bifurcations. Moreover, the dynamics and efficiency of microcombs are discussed, providing the accessibility of high-efficient, stable, and controllable combs. This work offers universal guidelines for operating mode-coupling-assisted combs in a normal-dispersion system.

7.
Zhongguo Zhong Yao Za Zhi ; 47(2): 469-475, 2022 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-35178991

RESUMO

This study aimed to investigate the anti-inflammatory effect of astragaloside Ⅳ in mice with ulcerative colitis(UC) and its effect on the percentage of peripheral blood T helper(Th17) cells. Following the establishment of UC mouse model with 2% sodium dextran sulfate(DSS), mice in the positive control group and low-and high-dose astragaloside Ⅳ groups were treated with corresponding drugs by gavage. Disease activity index(DAI) was calculated, and serum interleukin-17(IL-17), tumor necrosis factor-α(TNF-α), and transforming growth factor-ß(TGF-ß) levels were assayed by ELISA. The pathological changes in colon tissue were observed by HE staining, and Th17/regulatory T cells(Treg) ratio in the peripheral blood was determined by flow cytometry. Western blot was conducted for detecting the relative protein expression levels of forkhead box protein P3(Foxp3) and retinoic acid-related orphan nuclear receptor γT(ROR-γt). The findings demonstrated that in normal mice, the colonic structure was intact. The goblet cells were not reduced and the glands were neatly arranged, with no mucosal erosion, bleeding, or positive cell infiltration. In the model group, the colonic mucosal structure was seriously damaged, manifested as disordered arrangement or missing of glands, vascular dilatation, congestion, and massive inflammatory cell infiltration. The pathological injury of colon tissue was alleviated to varying degrees in drug treatment groups. Compared with the normal group, the model group exhibited elevated percentage of Th17 cells, increased IL-17 and TNF-α content, up-regulated relative ROR-γt protein expression, lowered TGF-ß, reduced percentage of Treg cells, and down-regulated relative Foxp3 protein expression. The comparison with the model group showed that DAI score, pathological score, percentage of Th17 cells, IL-17 and TNF-α content, and relative ROR-γt protein expression in the positive control group, low-dose astragaloside Ⅳ group, and high-dose astragaloside Ⅳ group were decreased, while TGF-ß content, percentage of Treg cells, and relative Foxp3 protein expression were increased. The DAI score, pathological score, percentage of Th17 cells, IL-17 and TNF-α content, and relative ROR-γt protein expression in the low-dose astragaloside Ⅳ group were higher than those in the positive control group, whereas the content of TGF-ß, percentage of Treg cells, and relative Foxp3 protein expression were lower. DAI score, pathological score, percentage of Th17 cells, IL-17 and TNF-α content, relative ROR-γt protein expression in the high-dose astragaloside Ⅳ group declined in contrast to those in the low-dose astragaloside Ⅳ group, while the TGF-ß content, percentage of Treg cells, and relative Foxp3 protein expression rose. There was no significant difference between the positive control group and the high-dose astragaloside Ⅳ group. Astragaloside Ⅳ is able to inhibit inflammatory response and diminish the percentage of Th17 cells in mice with UC.


Assuntos
Colite Ulcerativa , Saponinas , Triterpenos , Animais , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Camundongos , Saponinas/farmacologia , Linfócitos T Reguladores , Células Th17 , Triterpenos/farmacologia
8.
Nutr Metab Cardiovasc Dis ; 31(9): 2669-2677, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34362638

RESUMO

BACKGROUND AND AIMS: High-density lipoprotein cholesterol (HDL-C) concentration and variability are both important factors of cardiovascular disease (CVD) and mortality. We aimed to explore the associations of HDL-C and longitudinal change in HDL-C with risk of mortality. METHODS AND RESULTS: We recruited a total of 69,163 participants aged ≥40 years and had medical examination records of HDL-C during 2010-2014 from the Yinzhou District, Ningbo, China. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression models. We observed a non-linear association of HDL-C with risks of non-accidental and CVD mortality. Compared with the moderate concentration group (1.4-1.6 mmol/L), HDL-C <1 mmol/L was associated with a higher risk of non-accidental mortality (HR: 1.13 (95% CI: 1.01-1.27)) and both HDL-C <1 mmol/L and ≥2 mmol/L were associated with a higher risk of CVD mortality (HRs: 1.23 (95% CI: 1.01-1.50) and 1.37 (95% CI: 1.03-1.82), respectively). Compared with the stable group ([-0.1, +0.1 mmol/L]), a large decrease ([-0.5, -0.3 mmol/L]) and very large decrease (<-0.5 mmol/L) in HDL-C were associated with a higher risk of non-accidental mortality (HRs: 1.40 (95% CI: 1.21-1.63) and 1.78 (95% CI: 1.44-2.20), respectively). Similar results were observed for CVD mortality and cancer mortality. CONCLUSION: Extremely low or high HDL-C and a large decrease or very large decrease in HDL-C were associated with a higher risk of cause-specific mortality. Monitoring of HDL-C may have utility in identifying individuals at higher risk of mortality.


Assuntos
HDL-Colesterol/sangue , Dislipidemias/mortalidade , Hipercolesterolemia/mortalidade , Adulto , Idoso , Biomarcadores/sangue , China/epidemiologia , Dislipidemias/sangue , Dislipidemias/diagnóstico , Feminino , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/diagnóstico , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
9.
Int J Med Sci ; 18(16): 3624-3630, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34790034

RESUMO

Rationale: Since non-invasive tests for prediction of liver fibrosis have a poor diagnostic performance for detecting low levels of fibrosis, it is important to explore the diagnostic capabilities of other non-invasive tests to diagnose low levels of fibrosis. We aimed to evaluate the performance of radiomics based on 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) in predicting any liver fibrosis in individuals with biopsy-proven metabolic dysfunction-associated fatty liver disease (MAFLD). Methods: A total of 22 adults with biopsy-confirmed MAFLD, who underwent 18F-FDG PET/CT, were enrolled in this study. Sixty radiomics features were extracted from whole liver region of interest in 18F-FDG PET images. Subsequently, the minimum redundancy maximum relevance (mRMR) method was performed and a subset of two features mostly related to the output classes and low redundancy between them were selected according to an event per variable of 5. Logistic regression, Support Vector Machine, Naive Bayes, 5-Nearest Neighbor and linear discriminant analysis models were built based on selected features. The predictive performances were assessed by the receiver operator characteristic (ROC) curve analysis. Results: The mean (SD) age of the subjects was 38.5 (10.4) years and 17 subjects were men. 12 subjects had histological evidence of any liver fibrosis. The coarseness of neighborhood grey-level difference matrix (NGLDM) and long-run emphasis (LRE) of grey-level run length matrix (GLRLM) were selected to predict fibrosis. The logistic regression model performed best with an AUROC of 0.817 [95% confidence intervals, 0.595-0.947] for prediction of liver fibrosis. Conclusion: These preliminary data suggest that 18F-FDG PET radiomics may have clinical utility in assessing early liver fibrosis in MAFLD.


Assuntos
Fluordesoxiglucose F18 , Cirrose Hepática/diagnóstico , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto , Biópsia , China , Progressão da Doença , Feminino , Humanos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/patologia , Projetos Piloto , Valor Preditivo dos Testes , Prognóstico , Radiometria/métodos
10.
Int J Qual Health Care ; 33(2)2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33909042

RESUMO

OBJECTIVE: Unprecedented rigorous public health measures were implemented during the coronavirus disease 2019 (COVID-19) epidemic, but it is still unclear how the intervention influenced hospital visits for different types of diseases. We aimed to evaluate the impact of the intervention on hospital visits in Yinzhou District, Ningbo, Zhejiang province, China. METHODS: We conducted an interrupted time-series analysis from 1 January 2017 to 6 September 2020 based on the Yinzhou Health Information System in Ningbo, Zhejiang province. The beginning of the intervention was on 23 January 2020, and thus, there were 160 weeks before the intervention and 32 weeks after the implementation of the intervention. Level changes between expected and observed hospital visits in the post-intervention period were estimated using quasi-Poisson regression models. RESULTS: Compared with the expected level, there was an estimated decrease of -22.60% (95% confidence interval (CI): -27.53%, -17.36%) in the observed total hospital visits following the intervention. Observed hospital visits for diseases of the respiratory system were found to be decreased dramatically (-62.25%; 95% CI: -65.62%, -58.60%). However, observed hospital visits for certain diseases were estimated to be increased, including diseases of the nervous system (+11.17%; 95% CI: +3.21%, +19.74%); diseases of pregnancy, childbirth and the puerperium (+27.01%; 95% CI: +17.89%, +36.85%); certain conditions originating in the perinatal period (+45.05%; 95% CI: +30.24%, +61.56%); and congenital malformation deformations and chromosomal abnormalities (+35.50%; 95% CI: +21.24%, +51.45%). CONCLUSIONS: Our findings provided scientific evidence that cause-specific hospital visits evolve differently following the intervention during the COVID-19 epidemic.


Assuntos
COVID-19 , Hospitais/estatística & dados numéricos , COVID-19/epidemiologia , China/epidemiologia , Feminino , Humanos , Análise de Séries Temporais Interrompida , Pandemias , Gravidez , SARS-CoV-2
11.
Wilderness Environ Med ; 31(4): 426-430, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33132033

RESUMO

INTRODUCTION: High altitude polycythemia (HAPC) is a common chronic disease at high altitudes. It is characterized by excessive erythrocytosis (≥190 g·L-1 in females or ≥210 g·L-1 in males). HAPC severely jeopardizes the health status of plateau dwellers. The Qinghai-Tibet plateau, with an elevation above 4000 m, is the highest plateau in the world. Both Han and Tibetan populations residing there face the threat of HAPC. Therapeutic erythrocytapheresis (TE) was introduced to Tibet as an alternative to phlebotomy in 2015. METHODS: In this study, we retrospectively analyzed 155 patients with HAPC treated with TE in Tibet. Routine blood testing values before and after TE were compared to evaluate treatment efficacy. The efficiency rate, defined as the rate of increase in red blood cell depletion attained by TE compared with 450 mL whole blood phlebotomy, was calculated using whole blood volume and hematocrit before and after treatment and used to identify patients who maintained a normal hemoglobin level in the year after the TE procedure. RESULTS: On average, TE reduced red blood cell levels by 1.5×1012·L-1, hemoglobin concentration by 52 g·L-1, and hematocrit by 14% (P<0.001 for each). Patients who underwent TE with an efficiency rate ≥1.9 were more likely to maintain a normal hemoglobin level in the following year than those who underwent TE with an efficiency rate <1.9 (90 vs 28%, P<0.01). CONCLUSIONS: TE is a feasible therapeutic method to treat HAPC on the Qinghai-Tibet plateau. The efficiency rate is a useful tool to predict the expected interval between TE procedures.


Assuntos
Altitude , Citaferese/métodos , Policitemia/etiologia , Policitemia/terapia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tibet
12.
Zhongguo Zhong Yao Za Zhi ; 45(11): 2509-2514, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-32627482

RESUMO

Salvia miltiorrhiza(Sm) and Salvia castanea f. tomentosa(Sc) hairy roots were used as experimental materials to study the effects of six different carbon sources, galactose, fructose, lactose, glucose, arabinose and sucrose(control), on fresh weight, dry weight, contents and yields of salvianolic acids and tanshinones. The results showed that galactose was most beneficial to the growth of two kinds of hairy roots, while lactose and arabinose were not conducive to their growth. As for Sm hairy roots, fructose significantly promoted the accumulation of salvianolic acid B, and the content increased by 5.801 times and 10.151 times compared with the control group, respectively. Glucose significantly promoted the accumulation of salvianolic acids. The content and yield of rosmarinic acid were 7.674 times and 9.260 times of that of the control group, and the content and yield of salvianolic acid B were 5.532 times and 6.675 times of the control group. For the hairy roots of Sc, galactose significantly increased the content and yield of rosmarinic acid, reaching 7.820 times and 9.944 times of the control group, respectively. Fructose promoted the increase of the content and yield of cryptotanshinone, reaching 9.242 times and 6.609 times of the control group, respectively. The study confirmed the optimal carbon source for the hairy root culture of Sm and Sc, and provided theoretical guidance for large-scale production of Sm drug-derived components and the utilization of Sc.


Assuntos
Salvia miltiorrhiza , Salvia , Carbono , Raízes de Plantas
13.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(6): 867-871, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31880119

RESUMO

OBJECTIVE: To explore the effect of smoking on the histological subtype and prognosis of patients with lung adenocarcinoma (LAC) in China. METHODS: According to the new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society(IASLC/ATS/ERS)classification, 266 donors with primary LAC were reclassified. The correlation between clinicopathological factors including smoking status and the histological subtype was analyzed, and survival analysis was used to analyze the prognosis of primary LAC. RESULTS: There were four main histological subtypes including acinar predominant adenocarcinoma (APA) 30.1%, papillary predominant adenocarcinoma (PPA) 26.7%, solid predominant adenocarcinoma (SPA) 25.9%, and lepidic predominant adenocarcinoma (LPA) 11.7%.Smoking was associated with the histological subtype.The proportion of smokers was significantly higher than non-smokers in the SPA group, and the proportion of non-smokers was higher in other subtypes group. Cox regression model showed that the histological subtype and TNM stage were the independent predictors of prognostic in all patients.TNM stage was the predictor of postoperative survival in both smokers and non-smokers, and histological subtypes was the predictor only in smokers (ß=0.898, RR=2.455). Compared with the non-SPA group, the prognosis of the SPA group was significantly worse. CONCLUSION: Smoking is associated with SPA subtype, which affect the prognosis of primary LAC.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Fumar , China , Humanos , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos
14.
Appl Microbiol Biotechnol ; 102(24): 10791-10801, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30334090

RESUMO

Iron reduction mediated by Fe(III)-reducing bacteria (FeRB) occurs in aqueous environments and plays an essential role in removing contaminates in polluted freshwater lakes. Two model FeRB species, Shewanella and Geobacter, have been intensively studied because of their functions in bioremediation, iron reduction, and bioelectricity production. However, the abundance and community diversity of Shewanella and Geobacter in eutrophic freshwater lakes remain largely unknown. In this work, the distribution, abundance and biodiversity of Shewanella, Geobacter and other FeRB in the sediments of a heavily polluted lake, Chaohu Lake, China, across four successive seasons were investigated. Shewanella, Geobacter, and other FeRB were found to be widely distributed in the sediment of this heavily eutrophic lake. Geobacter was abundant with at least one order of magnitude more than Shewanella in cold seasons. Three Shewanella-related operational taxonomic units were detected and sixty one Geobacter-related operational taxonomic units were grouped into three phylogenetic clades. Thiobacillus, Desulfuromonas and Geobacter were identified as the main members of FeRB in the lake sediments. Interestingly, nutrients like carbon, nitrogen, and phosphorus were found to be the key factors governing the abundance and diversity of FeRB. Total FeRB, as well as Geobacter and Shewanella, were more abundant in the heavily eutrophic zone than those in the lightly eutrophic zone. The abundance and diversity of FeRB in the sediments of freshwater lakes were highly related with the degree of eutrophication, which imply that FeRB might have a great potential in alleviating the eutrophication and contamination in aqueous environments.


Assuntos
Geobacter , Sedimentos Geológicos/microbiologia , Ferro/metabolismo , Lagos/microbiologia , Shewanella , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , China , Clonagem Molecular , Eutrofização , Geobacter/genética , Geobacter/isolamento & purificação , Sedimentos Geológicos/química , Sequenciamento de Nucleotídeos em Larga Escala , Oxirredução , Filogenia , Shewanella/genética , Shewanella/isolamento & purificação , Microbiologia da Água , Poluição da Água
15.
Anal Bioanal Chem ; 409(12): 3233-3243, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28243708

RESUMO

In this paper, the effect of isotope-labeled analogs on the liquid chromatography-isotope dilution mass spectrometry (LC-IDMS) measurement was evaluated based on the comparison research of electrospray ionization responses (ESI) and matrix effect of melamine, 13C3-melamine, 13C3+15N3-melamine, and 15N3-melamine. The isotope-labeled melamines had similar ionization efficiency with melamine in the electrospray ionization source, but the intensity of corresponding quantitative fragment ions had distinctive differences. Based on the density functional theory at the B3LYP/6-311+G** level, this phenomenon was explained very well. The rare cleavage pathways of melamine, which just could be exactly identified by 15N-labeled melamines, resulted in the difference of quantitative fragment ions between 15N-labeled melamines and melamine. The interaction of ESI response between melamine and isotope-labeled melamines was investigated using MRM monitor mode. 15N-labeled melamine had significant ion inter-suppression effect on melamine, while 13C-labeled melamine had little influence on melamine. Finally, the influence of different isotope-labeled melamines on the LC-IDMS result was evaluated using the IDMS correction factor (θ). Taking the determination of melamine in milk powder as an example, the matrix effects of different isotope-labeled melamines and melamine had notable difference and the impact of this difference on the measurement results depended on the concentrations of analyte and matrix solution. It was worth noting that 15N3-melamine exhibited significant ion suppression to melamine in matrix solution. The deviation of the results from IDMS method might reach 59% using 15N3-melamine as internal standard in special matrix solution. Graphical Abstract The comparison of ESI responses of melamine, 13C3-melamine, 13C3+15N3-melamine and 15N3-melamine.


Assuntos
Espectrometria de Massas/métodos , Leite/química , Triazinas/análise , Animais , Isótopos de Carbono/análise , Cromatografia Líquida/métodos , Técnicas de Diluição do Indicador , Marcação por Isótopo/métodos , Isótopos de Nitrogênio/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
16.
Biodegradation ; 28(2-3): 139-144, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28154986

RESUMO

Several bacteria have been isolated to degrade 4-chloronitrobenzene. Degradation of 4-chloronitrobenzene by Cupriavidus sp. D4 produces 5-chloro-2-picolinic acid as a dead-end by-product, a potential pollutant. To date, no bacterium that degrades 5-chloro-2-picolinic acid has been reported. Strain f1, isolated from a soil polluted by 4-chloronitrobenzene, was able to co-metabolize 5-chloro-2-picolinic acid in the presence of ethanol or other appropriate carbon sources. The strain was identified as Achromobacter sp. based on its physiological, biochemical characteristics, and 16S rRNA gene sequence analysis. The organism completely degraded 50, 100 and 200 mg L-1 of 5-chloro-2-picolinic acid within 48, 60, and 72 h, respectively. During the degradation of 5-chloro-2-picolinic acid, Cl- was released. The initial metabolic product of 5-chloro-2-picolinic acid was identified as 6-hydroxy-5-chloro-2-picolinic acid by LC-MS and NMR. Using a mixed culture of Achromobacter sp. f1 and Cupriavidus sp. D4 for degradation of 4-chloronitrobenzen, 5-chloro-2-picolinic acid did not accumulate. Results infer that Achromobacter sp. f1 can be used for complete biodegradation of 4-chloronitrobenzene in remedial applications.


Assuntos
Achromobacter/metabolismo , Ácidos Picolínicos/metabolismo , Achromobacter/isolamento & purificação , Biodegradação Ambiental , Cromatografia Líquida , Técnicas de Cocultura , Cupriavidus/metabolismo , Hidroxilação , Cinética , Espectrometria de Massas , Metaboloma , Nitrobenzenos/metabolismo , Espectroscopia de Prótons por Ressonância Magnética
17.
J Cell Mol Med ; 20(3): 526-36, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26805397

RESUMO

Gastric cancer is one of the most common malignancies worldwide. Interleukin-1-beta (IL-1ß) is a pro-inflammatory cytokine and potent inhibitor of gastric acid secretion. Some studies provided evidence of the association between IL-1B 31 polymorphism and gastric cancer risk while other studies did not. Therefore, we conducted a comprehensive meta-analysis to reassess the association. A systematic literature search of the PubMed and EMBASE databases identified 37 studies with 6108 cases and 8980 controls for this meta-analysis. The crude odd ratios (ORs) and the 95% confidence intervals (CIs) were calculated to evaluate the strength of the association. Meta-regression was used to determine the major source of heterogeneity across the studies. The pooled analysis did not suggest the significant association of IL-1B 31 C>T polymorphism with gastric cancer risk. Stratified analysis was performed by ethnicity, source of control, genotype method, and indicated a significantly increased gastric cancer risk associated with IL-1B 31T variant in the population-based subgroup (heterozygous model: OR = 1.22, 95% CI = 1.03-1.45). Moreover, stratified analysis by Helicobacter pylori infection status indicated that IL-1B 31 polymorphism increased gastric cancer risk in infection-positive subgroup (homozygous model: OR = 1.35, 95% CI = 1.02-1.78; heterozygous model: OR = 1.31, 95% CI = 1.04-1.66; recessive model: OR = 1.29, 95% CI = 1.04-1.61). The study suggested that IL-1B 31 polymorphism might confer susceptibility to gastric cancer in the presence of H. pylori infection, indicating a gene-environment interaction in gastric carcinogenesis.


Assuntos
Infecções por Helicobacter/genética , Helicobacter pylori/fisiologia , Interleucina-1beta/genética , Neoplasias Gástricas/genética , Estudos de Casos e Controles , Interação Gene-Ambiente , Estudos de Associação Genética , Predisposição Genética para Doença , Infecções por Helicobacter/microbiologia , Humanos , Polimorfismo de Nucleotídeo Único , Neoplasias Gástricas/microbiologia
18.
Opt Express ; 24(15): 16815-21, 2016 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-27464134

RESUMO

Planar photonics using metasurfaces is of great interest because a metasurface can control the flow of light beyond that attainable with natural materials. The resonance wavelength of a binary-grating metasurface is adjustable by changing the width and thickness of the nanostructure. We propose a novel combination of nematic liquid crystals and a binary-grating metasurface with which the diffraction efficiency can be controlled by adjusting the applied voltage.

19.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(5): 570-3, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-27386649

RESUMO

OBJECTIVE: To explore the correlation between signs of living body in abdominal and pelvic cavities and syndrome typing of Chinese medicine (CM) in colorectal cancer patients. METHODS: Totally 112 colorectal cancer patients undergoing open abdominal surgery or laporoscopic surgery were syndrome typed as five types, i.e., inner-accumulation of damp and heat, blockage of stasis and toxin, Pi-Shen yang deficiency, blood-qi deficiency, Gan-Shen yin deficiency. Signs of living body in abdominal and pelvic cavities were collected. The correlation between signs of living body in abdominal and pelvic cavities and syndrome typing of CM were analyzed. RESULTS: Red colorectal canals or mass were dominated in colorectal cancer patients with inner-accumulation of damp and heat syndrome. Dark purple colorectal canals or mass were dominated in colorectal cancer patients with blockage of stasis and toxin syndrome. Reddish colorectal canals or mass were dominated in colorectal cancer patients with blood-qi deficiency syndrome. Pale colorectal canals or mass were dominated in colorectal cancer patients with Pi-Shen yang deficiency syndrome. Whitish or red-white stripes were dominated in colorectal cancer patients with Gan-Shen yin deficiency syndrome. Dropsy colorectal canal was associated with Pi-Shen yang deficiency syndrome. Intracavitary effusion was often seen in colorectal cancer patients with inner-accumulation of damp and heat syndrome. The effusion was yellowish in less amount. Intracavitary adhesion was often seen in colorectal cancer patients with blockage of stasis and toxin syndrome. There was no correlation between the maximum diameter of mass or each syndrome type of CM. CONCLUSION: There existed correlation between signs of living body in abdominal and pelvic cavities and syndrome typing of CM, which could be taken as one of references for syndrome typing of colorectal cancer patients.


Assuntos
Cavidade Abdominal/patologia , Neoplasias Colorretais/diagnóstico , Medicina Tradicional Chinesa , Pelve/patologia , Neoplasias Colorretais/cirurgia , Humanos , Deficiência da Energia Yang/diagnóstico , Deficiência da Energia Yin/diagnóstico
20.
Bioorg Med Chem Lett ; 25(2): 285-7, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25488843

RESUMO

A series of novel arylpiperazine derivatives was synthesized. The in vitro cytotoxic activities of all synthesized compounds against three human prostate cancer cell lines (PC-3, LNCaP, and DU145) were evaluated by a CCK-8 assay. Compounds 10, 24 and 29 exhibited strong cytotoxic activities against LNCaP cells (IC50 <3µM). In addition, these compounds exhibited weak cytotoxic effects on human epithelial prostate normal cells RWPE-1. The structure-activity relationship (SAR) of these arylpiperazine derivatives was also discussed based on the obtained experimental data.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Piperazinas/síntese química , Piperazinas/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Modelos Moleculares , Estrutura Molecular , Neoplasias da Próstata/patologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
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