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1.
BMC Microbiol ; 23(1): 386, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38053022

RESUMO

BACKGROUND: There is a link between Helicobacter pylori (HP) infection and small intestinal bacterial overgrowth (SIBO) with nonspecific digestive symptoms. Nonetheless, whether HP infection is associated with SIBO in adults remains unclear. Based on a meta-analysis, we evaluated this relationship. RESULTS: Observational studies relevant to our research were identified by searching PubMed, Embase, the Cochrane Library, and the Web of Science. We evaluated between-study heterogeneity using the Cochrane Q test and estimated the I2 statistic. Random-effects models were used when significant heterogeneity was observed; otherwise, fixed-effects models were used. Ten datasets from eight studies, including 874 patients, were involved in the meta-analysis. It was shown that HP infection was related to a higher odds of SIBO (odds ratio [OR]: 1.82, 95% confidence interval: 1.29 to 2.58, p < 0.001) with mild heterogeneity (p for Cochrane Q test = 0.11, I2 = 7%). Subgroup analyses showed that HP infection was related to SIBO in young patients (mean age < 48 years, OR: 2.68, 95% CI: 1.67 to 4.28, p < 0.001; I2 = 15%) but not in older patients (mean age ≥ 48 years, OR: 1.15, 95% CI: 0.69 to 1.92, p < 0.60; I2 = 1%; p for subgroup difference = 0.02). Subgroup analyses further indicated that the association was not significantly affected by the country of study, comorbidities, exposure to proton pump inhibitors, or methods of evaluating HP infection and SIBO. CONCLUSIONS: HP infection may be related to SIBO in adults, which supports the detection of SIBO in patients with digestive symptoms and HP infection.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Adulto , Humanos , Pessoa de Meia-Idade , Intestino Delgado/microbiologia , Inibidores da Bomba de Prótons
2.
Langmuir ; 33(21): 5108-5116, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28489408

RESUMO

Noble metal nanoclusters (NCs) show great promise as nanoprobes for bioanalysis and cellular imaging in biological applications due to ultrasmall size, good photophysical properties, and excellent biocompatibility. In order to achieve a comprehensive understanding of possible biological implications, a series of spectroscopic measurements were conducted under different temperatures to investigate the interactions of Au NCs (∼1.7 nm) with three model plasmatic proteins (human serum albumin (HSA), γ-globulins, and transferrin). It was found that the fluorescence quenching of HSA and γ-globulins triggered by Au NCs was due to dynamic quenching mechanism, while the fluorescence quenching of transferrin by Au NCs was a result of the formation of a Au NC-transferrin complex. The apparent association constants of the Au NCs bound to HSA, γ-globulins, and transferrin demonstrated no obvious difference. Thermodynamic studies demonstrated that the interaction between Au NCs and HSA (or γ-globulins) was driven by hydrophobic forces, while the electrostatic interactions played predominant roles in the adsorption process for transferrin. Furthermore, it was proven that Au NCs had no obvious interference in the secondary structures of these three kinds of proteins. In turn, these three proteins had a minor effect on the fluorescence intensity of Au NCs, which made fluorescent Au NCs promising in biological applications owing to their chemical and photophysical stability. In addition, by comparing the interactions of small molecules, Au NCs, and large nanomaterials with serum albumin, it was found that the binding constants were gradually increased with the increase of particle size. This work has elucidated the interaction mechanisms between nanoclusters and proteins, and shed light on a new interaction mode different from the protein corona on the surface of nanoparticles, which will highly contribute to the better design and applications of fluorescent nanoclusters.


Assuntos
Ouro/química , Humanos , Nanopartículas Metálicas , Albumina Sérica Humana , Termodinâmica , Transferrina , gama-Globulinas
3.
J Hazard Mater ; 308: 139-48, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-26808252

RESUMO

As noble metal nanoclusters (NCs) are widely employed in nanotechnology, their potential threats to human and environment are relatively less understood. Herein, the biological effects of ultra-small silver NCs coated by bovine serum albumin (BSA) (Ag-BSA NCs) on isolated rat liver mitochondria were investigated by testing mitochondrial swelling, membrane permeability, ROS generation, lipid peroxidation and respiration. It was found that Ag-BSA NCs induced mitochondrial dysfunction via synergistic effects of two different ways: (1) inducing mitochondrial membrane permeability transition (MPT) by interacting with the phospholipid bilayer of the mitochondrial membrane (not with specific MPT pore proteins); (2) damaging mitochondrial respiration by the generation of reactive oxygen species (ROS). As far as we know, this is the first report on the biological effects of ultra-small size nanoparticles (∼2 nm) at the sub-cellular level, which provides significant insights into the potential risks brought by the applications of NCs. It would inspire us to evaluate the potential threats of nanomaterials more comprehensively, even though they showed no obvious toxicity to cells or in vivo animal models. Noteworthy, a distinct toxic mechanism to mitochondria caused by Ag-BSA NCs was proposed and elucidated.


Assuntos
Mitocôndrias Hepáticas/efeitos dos fármacos , Nanoestruturas/toxicidade , Soroalbumina Bovina/toxicidade , Prata/toxicidade , Animais , Peroxidação de Lipídeos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Mitocôndrias Hepáticas/fisiologia , Mitocôndrias Hepáticas/ultraestrutura , Membranas Mitocondriais/efeitos dos fármacos , Dilatação Mitocondrial/efeitos dos fármacos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Soroalbumina Bovina/química , Prata/química
4.
Environ Sci Technol ; 47(17): 9866-73, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23919591

RESUMO

Molecular diffusion across the sediment-water interface, as one of the key geochemical processes, dictates whether a sediment is a source or sink of chemicals, providing useful data in designing remedial actions. Despite ample previous efforts in quantifying sediment-water diffusion fluxes, the resulting methods are largely unsatisfactory. Herein, we introduce a novel passive sampling device capable of measuring vertical profiles of chemical concentrations near the sediment-water interface, from which diffusion fluxes can be calculated based on a model that we developed. In laboratory testing, diffusion fluxes (0.032-310 ng m(-2) d(-1)) of dichlorodiphenyltrichloroethane and its metabolites obtained from the present sampling device were consistent with those (0.38-610 ng m(-2) d(-1)) determined by using a conventional active sampling method, solid-phase extraction/liquid-liquid extraction. Field deployment of the sampling device yielded individual diffusion fluxes of p,p'-DDD, p,p'-DDE, p,p'-DDMU, o,p'-DDMU, p,p'-DDNU, and p,p'-DBP in the range of 5.9-150 ng m(-2) d(-1), which were comparable to those (5.5-85 ng m(-2) d(-1)) obtained with a benthic chamber. Moreover, diffusion fluxes of p,p'-DDT and o,p'-DDT obtained with the sampling device were negative; i.e., the sediment is acting as a sink for these chemicals, while that could not be found using the benthic chamber. Thus, the passive sampling device can provide better information about the movement of chemicals through the sediment and overlying water for the choice of remedial strategies.


Assuntos
Monitoramento Ambiental/métodos , Água Doce/análise , Sedimentos Geológicos/análise , Hidrocarbonetos Clorados/análise , Extração Líquido-Líquido/métodos , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Interações Hidrofóbicas e Hidrofílicas , Modelos Teóricos , Polietileno/química
5.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 33(6): 840-4, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-23980370

RESUMO

OBJECTIVE: To investigate whether oxymatrine (OM) could promote mesenchymal stem cell (MSC) therapy in CCl4-induced hepatic fibrosis (HF) in rats and to initially explore its mechanisms. METHODS: Totally 50 male SD rats were randomly divided into five groups,i.e., the normal control group, the model group, the MSC therapy group, the OM therapy group, and the MSC combined OM therapy group, 10 in each group. Except the normal control group, the HF model was duplicated by CCl4 induction. After successful modeling, rats in the MSC therapy group received 5 x10(6) MSCs by intravenous injection via caudal vein, once a week. Rats in the OM therapy group received 50 mg/kg OM by intramuscular injection, three times a week. Rats in MSC combined OM therapy group received 5 x 10(6) MSCs by intravenous injection via caudal vein, once a week and 50 mg/kg OM by intramuscular injection three times a week. Equal volume of normal saline was given to those in the normal control group and the model group. All medication lasted for 8 weeks. Serum levels of ALT and AST were detected 8 weeks later. The hepatic histopathological injury and extracellular matrix deposit were assessed using HE and Masson staining. Expressions of serum interleukin-4 (IL-4) and interleukin-10 (IL-10) were detected using enzyme linked immunosorbent assay (ELISA). RESULTS: (1) Compared with the normal control group, serum levels of ALT and AST significantly increased in the model group (P < 0.05). Compared with the model group, serum levels of ALT and AST significantly decreased in the OM therapy group, the MSC therapy group, and the MSC combined OM therapy group at the end of 8 weeks of treatment (P < 0.05). But serum levels of ALT and AST were significantly lower in the MSC combined OM therapy group than in the OM therapy group and the MSC therapy group (P < 0.05). (2) Compared with the model group, the hepatic injury was significantly lessened and the area of extracellular matrix deposit was significantly reduced in the OM therapy group, the MSC therapy group, and the MSC combined OM therapy group (P < 0.05). Besides, they wer more significant in the MSC combined OM therapy group (P < 0.05). (3) Compared with the model group, the serum IL-4 level was significantly higher in the MSC therapy group and the MSC combined MO group (P < 0.05). It was higher in the MSC combined MO group (P < 0.05). Although the serum IL-4 level also increased in the OM therapy group, but with no statistical difference (P > 0.05). (4) The serum IL-10 level significantly increased in the OM therapy group, the MSC therapy group, and the MSC combined OM therapy group (P < 0.05), and it was the highest in the MSC combined OM therapy group among the three groups (P < 0.05). (5) Two-photon fluorescence imaging showed no signals of MSCs in liver with or without OM injection. CONCLUSION: OM could promote mesenchymal stem cell therapy in hepatic fibrosis rats, which might be involved in increasing serum levels of IL-4 and IL-10.


Assuntos
Alcaloides/uso terapêutico , Cirrose Hepática Experimental/terapia , Transplante de Células-Tronco Mesenquimais , Quinolizinas/uso terapêutico , Animais , Interleucina-10/sangue , Interleucina-4/sangue , Masculino , Ratos , Ratos Sprague-Dawley
6.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 33(5): 679-85, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-23905391

RESUMO

OBJECTIVE: To analyze differentially expressed proteins of hepatic stellate cells (HSCs) treated with oxymatrine (OMT) liposomes, thus further exploring the molecular mechanism of OMT liposomes for treating liver fibrosis. METHODS: A rat model of CCl4 induced chronic liver fibrosis was established. HSCs were perfusion isolated from modeled SD rats and cultured in vitro . Passage 2 HSCs were divided into the model group (Group A), the OMT-liposome-treated group (Group B), and the liposome-treated control group (Group C). HSCs from normal rats were taken as the normal control group (Group D). The total proteins of HSCs cells were extracted from Group B and D after 7 days of treatment, and separated with isoelectrofocusing two-dimensional electrophoresis (2-DE). A 2-DE system was established to analyze the differences in the protein profile between Group B and Group C. Tow protein dots with most obvious difference were selected to determine the structures and functions of different proteins using peptide mass fingerprinting (PMF). RESULTS: (1) The total number bf proteins decreased after treated with OMT liposomes, with 864 spots before treatment and 756 spots after treatment, and the matching rate was 63%. (2) According to 2-DE results, 10 differential protein spots were found by image analysis of magnifying images in local regions. (3) Two most differently expressed proteins were identified to be ATM (46. 236 kD) and Miz1 (54. 051 kD) by PMF and SWISS-PROT protein database retrieval. CONCLUSION: Action of OMT liposomes on HSCs of rats with chronic liver fibrosis caused different protein expressions, which might be involved in the signaling pathways of inducing the apoptosis of HSCs.


Assuntos
Alcaloides/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Proteoma/metabolismo , Quinolizinas/farmacologia , Animais , Eletroforese em Gel Bidimensional , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/metabolismo , Lipossomos , Cirrose Hepática Experimental/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
7.
Anal Chem ; 85(15): 7117-24, 2013 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-23808846

RESUMO

In situ measurements of hydrophobic organic chemicals in sediment porewater, a central component in assessing the bioavailability and mobility of chemicals in sediment, have been scarce. Here, we introduce a multisection passive sampler with low-density polyethylene (LDPE) as the sorbent phase, which is appropriate for measuring vertical concentration profiles of chemicals in sediment porewater. This sampler is composed of a series of identical sampling cells insulated with seclusion rings. In each section, sorption of chemicals into LDPE is diffusion-controlled through the water layer separated from the sediment by a glass fiber filtration membrane and a porous stainless steel shield. Pilot laboratory testing indicated that the sampler can roughly determine the porewater concentrations of 1,1-dichloro-2,2-bis-(chlorophenyl)ethane (p,p'-DDD) and 1,1-dichloro-2,2-bis-(chlorophenyl)ethylene (p,p'-DDE), comparable to those yielded through centrifugation/liquid-liquid extraction, a conventional technique for sampling sediment porewater. Field deployment of the sampler was performed in an urbanized coastal region to measure the depth profiles of dichlorodiphenyltrichloroethane and its metabolites in sediment porewater. Sampling rate-calibrated and performance reference compound-calibrated concentrations were calculated, which were consistent with those obtained by the centrifugation/liquid-liquid extraction method. These results verified the utility of the sampler for measuring depth profiles of sediment porewater chemicals.


Assuntos
DDT/análise , DDT/metabolismo , Sedimentos Geológicos/química , Água/química , Centrifugação , DDT/isolamento & purificação , Limite de Detecção , Extração Líquido-Líquido , Água do Mar/química , Solo
8.
Food Chem Toxicol ; 56: 1-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23416648

RESUMO

The effect of casein glycomacropeptide (GMP) as a specific regulating mediator in obese rats induced by high-fat (HF) diet was investigated. Male obese Sprague-Dawley (SD) rats induced by high-fat diet for 8 weeks period were fed high-fat, high-fat with GMP of 100 mg/kg BW (HFLG), 200 mg/kg BW (HFMG) and 400mg/kg BW (HFHG) for 6 weeks. Compared with the high-fat control (HFC) group GMP supplementation significantly decreased adipose tissue weight, activity of fatty acid synthase (FAS) and glycerol-3-phosphate dehydrogenase (GPDH). Hepatic lipid droplet size, plasma and hepatic lipid levels markedly reduced. Moreover, GMP reduces plasma total cholesterol and low-density lipoprotein (LDL) cholesterol as well as hepatic-cholesterol and triglycerides. The liver steatosis observed in obese rats was also prevented by GMP supplement. In addition, GMP significantly diminished mitochondrial and liver malondialdehyde (MDA) production, and obviously elevated the activities of mitochondrial and hepatic superoxidase dismutase (SOD) and glutathione peroxidase (GSH-Px). Leptin production and proinflammatory cytokines such as TNF-α and IL-6 secretion decreased. Taken together, GMP can reduce lipid accumulation and enhance antioxidant capability of obese rats. It suggests that GMP can counteract high-fat diet-induced obesity, which might make it a potential ingredient with anti-obesity activity.


Assuntos
Caseínas/farmacologia , Dieta Hiperlipídica/efeitos adversos , Obesidade/tratamento farmacológico , Fragmentos de Peptídeos/farmacologia , Tecido Adiposo/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Ácido Graxo Sintases/metabolismo , Fígado Gorduroso/sangue , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/prevenção & controle , Glicerolfosfato Desidrogenase/metabolismo , Interleucina-6/sangue , Interleucina-6/metabolismo , Leptina/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Obesidade/etiologia , Ratos , Ratos Sprague-Dawley , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo
9.
PLoS One ; 7(12): e50850, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23251393

RESUMO

It is recognized that endogenous cannabinoids, which signal through CB1 receptors in hepatic stellate cells (HSCs), exert a profibrotic effect on chronic liver diseases. In this study, we suppressed CB1 expression by lentivirus mediated small interfering RNA (CB1-RNAi-LV) and investigated its effect on hepatic fibrosis in vitro and in vivo. Our results demonstrated that CB1-RNAi-LV significantly inhibited CB1 expression, and suppressed proliferation and extracellular matrix production in HSCs. Furthermore, CB1-RNAi-LV ameliorated dimethylnitrosamine induced hepatic fibrosis markedly, which was associated with the decreased expression of mesenchymal cell markers smooth muscle α-actin, vimentin and snail, and the increased expression of epithelial cell marker E-cadherin. The mechanism lies on the blockage of Smad signaling transduction induced by transforming growth factor ß1 and its receptor TGF-ß RII. Our study firstly provides the evidence that CB1-RNAi-LV might ameliorate hepatic fibrosis through the reversal of epithelial-to-mesenchymal transition (EMT), while the CB1 antagonists AM251 had no effect on epithelial-mesenchymal transitions of HSCs. This suggests that CB1 is implicated in hepatic fibrosis and selective suppression of CB1 by small interfering RNA may present a powerful tool for hepatic fibrosis treatment.


Assuntos
Transição Epitelial-Mesenquimal/genética , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/genética , Fígado/metabolismo , Receptor CB1 de Canabinoide/genética , Animais , Apoptose/genética , Caderinas/genética , Caderinas/metabolismo , Proliferação de Células , Células Estreladas do Fígado/patologia , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/metabolismo
10.
World J Gastroenterol ; 18(31): 4199-206, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22919254

RESUMO

AIM: To investigate the potential mechanism of Arg-Gly-Asp (RGD) peptide-labeled liposome loading oxymatrine (OM) therapy in CCl4-induced hepatic fibrosis in rats. METHODS: We constructed a rat model of CCl4-induced hepatic fibrosis and treated the rats with different formulations of OM. To evaluate the antifibrotic effect of OM, we detected levels of alkaline phosphatase, hepatic histopathology (hematoxylin and eosin stain and Masson staining) and fibrosis-related gene expression of matrix metallopeptidase (MMP)-2, tissue inhibitor of metalloproteinase (TIMP)-1 as well as type I procollagen via quantitative real-time polymerase chain reaction. To detect cell viability and apoptosis of hepatic stellate cells (HSCs), we performed 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide assay and flow cytometry. To reinforce the combination of oxymatrine with HSCs, we constructed fluorescein-isothiocyanate-conjugated Arg-Gly-Asp peptide-labeled liposomes loading OM, and its targeting of HSCs was examined by fluorescent microscopy. RESULTS: OM attenuated CCl4-induced hepatic fibrosis, as defined by reducing serum alkaline phosphatase (344.47 ± 27.52 U/L vs 550.69 ± 43.78 U/L, P < 0.05), attenuating liver injury and improving collagen deposits (2.36% ± 0.09% vs 7.70% ± 0.60%, P < 0.05) and downregulating fibrosis-related gene expression, that is, MMP-2, TIMP-1 and type I procollagen (P < 0.05). OM inhibited cell viability and induced apoptosis of HSCs in vitro. RGD promoted OM targeting of HSCs and enhanced the therapeutic effect of OM in terms of serum alkaline phosphatase (272.51 ± 19.55 U/L vs 344.47 ± 27.52 U/L, P < 0.05), liver injury, collagen deposits (0.26% ± 0.09% vs 2.36% ± 0.09%, P < 0.05) and downregulating fibrosis-related gene expression, that is, MMP-2, TIMP-1 and type I procollagen (P < 0.05). Moreover, in vitro assay demonstrated that RGD enhanced the effect of OM on HSC viability and apoptosis. CONCLUSION: OM attenuated hepatic fibrosis by inhibiting viability and inducing apoptosis of HSCs. The RGD-labeled formulation enhanced the targeting efficiency for HSCs and the therapeutic effect.


Assuntos
Alcaloides/administração & dosagem , Alcaloides/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/patologia , Cirrose Hepática/prevenção & controle , Quinolizinas/administração & dosagem , Quinolizinas/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Tetracloreto de Carbono/efeitos adversos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Células Estreladas do Fígado/metabolismo , Técnicas In Vitro , Lipossomos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Ratos , Ratos Sprague-Dawley , Inibidor Tecidual de Metaloproteinase-1/metabolismo
11.
Environ Toxicol Chem ; 31(5): 1012-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22388779

RESUMO

A passive water sampler with low-density polyethylene (LDPE) as the sorbent phase was built and field-tested for sensing freely dissolved concentrations of hydrophobic organic compounds (HOCs) in fresh and coastal water. Based on the measured LDPE-water partition coefficients (K(pew)) of 12 polycyclic aromatic hydrocarbons (PAHs) and dichlorodiphenyltrichloroethane (DDT) and its seven metabolites, the detection limits with the passive sampler containing 10-g LDPE ranged from 0.04 to 56.9 pg/L in the equilibrium sampling mode. Furthermore, the utility of the passive sampler in measuring dissolved HOC concentrations in open waters was examined through a comparison with solid-phase extraction combined with liquid-liquid extraction (SPE-LLE) and poly(dimethyl)siloxane (PDMS) coated fiber samplers. The total concentrations of PAHs (3.8-16 ng/L) obtained by the passive sampler were lower than those (87.7-115.5 ng/L) obtained through SPE-LLE. This large difference was probably attributable to slower water exchange in and out of the passive sampler as time progressed because of blockage by algae in eutrophia reservoirs and high dissolved organic carbon contents resulting in higher-than-expected PAH concentrations by SPE-LLE. Furthermore, the concentrations and compositional profiles of DDXs (sum of p,p'-DDT, p,p'-DDD, p,p'-DDE, o,p'-DDT, o,p'-DDD, o,p'-DDE, and p,p'-DDMU) at site A obtained by the passive sampler agreed with the results obtained with the PDMS-coated fibers, suggesting that the passive sampler was able to reasonably quantify dissolved HOCs in seawater.


Assuntos
Monitoramento Ambiental/métodos , Água Doce/análise , Compostos Orgânicos/análise , Polietileno/química , Água do Mar/análise , Poluentes Químicos da Água/análise , DDT/análise , Interações Hidrofóbicas e Hidrofílicas , Hidrocarbonetos Policíclicos Aromáticos/análise
12.
Cancer Immunol Immunother ; 61(3): 335-42, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21913024

RESUMO

Tumor immune tolerance plays a critical role in tumor cell survival; the establishment of tumor immune tolerance is incompletely understood yet. Integrin alphavbeta6 (avb6) is involved in tumor growth and metastasis. This study aimed to observe the effect of avb6 on the development of tumor tolerance in colorectal cancer (CRC). In this study, 28 CRC patients were recruited. The frequencies of tolerogenic dendritic cells (TolDC), regulatory T cells (Treg), and CD8+ T cells in surgically removed CRC tissue were assessed by flow cytometry. The levels of avb6 in CRC tissue were measured by enzyme-linked immunoassay (ELISA). The effect of avb6 on inducing TolDCs and Tregs was evaluated with the cell culture model. The results showed that in surgically removed CRC tissue, we detected higher frequencies of TolDC and Tregs, lower frequency CD8+ T cells and high levels of avb6 as compared with non-CRC tissue. CRC protein extracts could induce TolDC development that could be blocked by anti-avb6 antibody. CRC-derived DCs could convert naïve CD4+ T cells to Tregs. Peripheral CD8+ T cells from CRC patients still retained the ability to produce granzyme B and to proliferate in response to CRC tumor antigen in culture that was abolished by the presence of CRC-derived Tregs. We conclude that CRC-derived avb6 is involved in the establishment of tumor immune tolerance in local tissues.


Assuntos
Antígenos de Neoplasias/imunologia , Neoplasias Colorretais/imunologia , Tolerância Imunológica/imunologia , Integrinas/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/metabolismo , Western Blotting , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células , Células Cultivadas , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Granzimas/imunologia , Granzimas/metabolismo , Humanos , Integrinas/metabolismo , Masculino , Pessoa de Meia-Idade , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo
13.
Oncol Res ; 20(4): 139-47, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23461060

RESUMO

MicroRNAs (miRNAs) are endogenous small noncoding RNAs that negatively regulate gene expression at the posttranscriptional level and play an important role in carcinogenesis. Herein, we characterized the global expression of miRNA in distal gastric adenocarcinomas and determined if circulating miRNAs could be used as biomarkers for distal gastric adenocarcinoma. We used a microarray screening system to detect dysregulated miRNAs in distal gastric adenocarcinoma tissues. The expression of a subset of five aberrantly expressed miRNAs (miR-375, -196b, -204, -18b, and -93) were further quantified in an independent set of clinical samples of distal gastric adenocarcinoma by real-time quantitative RT-PCR (rt-qRT-PCR). We also used rt-qRT-PCR to investigate the expression levels of putative miRNA biomarkers in serum and tumor cell lines. In our study, the expression of a subset of microRNAs was altered in distal gastric adenocarcinoma compared to normal tissue, miR-375 was significantly downregulated in distal gastric adenocarcinoma tissues, to a level that was significantly lower than cardia adenocarcinoma (p < 0.05). The circulating serum levels of miR-375 in patients who had distal gastric adenocarcinoma were also much lower than normal controls (p < 0.001). As a biomarker, miR-375 yielded a receiver operating characteristic area under the curve of 0.835. The specificity and sensitivity was 80% and 85%, respectively, in the discrimination of distal gastric adenocarcinoma from control, at a normalized cutoff of 0.218. The expression of miR-375 was downregulated both in distal gastric adenocarcinoma tissues and serum of patients with distal gastric adenocarcinoma. These data suggest miR-375 is a potential biomarker for distal gastric adenocarcinoma.


Assuntos
Adenocarcinoma/diagnóstico , Biomarcadores Tumorais/análise , MicroRNAs/análise , Neoplasias Gástricas/diagnóstico , Adenocarcinoma/genética , Idoso , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/genética
14.
J Agric Food Chem ; 56(21): 10041-7, 2008 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-18925741

RESUMO

Flaxseed is the richest dietary source of the lignan secoisolariciresinol diglucoside (SDG) and contains the largest amount of SDG oligomers, which are often hydrolyzed to break the ester linkages for the release of SDG and the glycosidic bonds for the release of secoisolariciresinol (SECO). The alkaline hydrolysis reaction kinetics of SDG oligomers from flaxseed and the acid hydrolysis process of SDG and other glucosides were investigated. For the kinetic modeling, a pseudo-first-order reaction was assumed. The results showed that the alkaline hydrolysis of SDG oligomers followed first-order reaction kinetics under mild alkaline hydrolytic conditions and that the concentration of sodium hydroxide had a strong influence on the activation energy of the alkaline hydrolysis of SDG oligomers. The results also indicated that the main acid hydrolysates of SDG included secoisolariciresinol monoglucoside (SMG), SECO, and anhydrosecoisolariciresinol (anhydro-SECO) and that the extent and the main hydrolysates of the acid hydrolysis reaction depended on the acid concentration, hydrolysis temperature, and time. In addition, the production and change of p-coumaric acid glucoside, ferulic acid glucoside and their methyl esters and p-coumaric acid, ferulic acid, and their methyl esters during the process of hydrolysis was also investigated.


Assuntos
Butileno Glicóis/química , Linho/química , Glucosídeos/química , Sementes/química , Glicosídeos/química , Hidrólise , Cinética
16.
J Chromatogr A ; 1185(2): 223-32, 2008 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-18272161

RESUMO

Flaxseed contains the largest amount of lignan secoisolariciresinol diglucoside (SDG) oligomers and is the richest dietary source of SDG. SDG oligomers in the flaxseed extract are often hydrolyzed to break the ester linkages for the release of SDG and the glycosidic bonds for the release of secoisolariciresinol (SECO). The hydrolysates of SDG oligomers are complicated because of the production of esters in an alcohol-containing medium. In this study, a new gradient reversed-phase high-performance liquid chromatography (HPLC) method has been developed to be suitable for the separation and determination of: (1) SDG oligomers extracted from the defatted flaxseed powder by a 70% aqueous methanol solution; (2) SDG oligomers and their alkaline hydrolysates, including SDG, p-coumaric acid glucoside and its methyl ester, ferulic acid glucoside and its methyl ester in an alkaline hydrolytic solution; and (3) the succedent acid hydrolysates, including secoisolariciresinol monoglucoside (SMG), SECO, anhydrosecoisolariciresinol (anhydro-SECO), p-coumaric acid and its methyl ester, ferulic acid and its methyl ester, 5-hydroxymethyl-2-furfural (HMF) and its degradation product in an acid hydrolytic solution. The content of SDG oligomers in a defatted flaxseed powder was found to be 38.5 mg/g on a dry matter basis, corresponding to a SDG content of 15.4 mg/g, which was determined after alkaline hydrolysis. Furthermore, this study presented a major reaction pathway for the hydrolysis of SDG oligomers.


Assuntos
Butileno Glicóis/análise , Cromatografia Líquida de Alta Pressão/métodos , Linho/química , Glucosídeos/análise , Sementes/química , Butileno Glicóis/química , Butileno Glicóis/isolamento & purificação , Glucosídeos/química , Glucosídeos/isolamento & purificação , Hidrólise
17.
Huan Jing Ke Xue ; 28(9): 2035-40, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-17990553

RESUMO

A composite flocculant (denoted JYF-1), made of polyaluminum chloride (PAC) and polydimethyldiallyammonium chloride (PDMDAAC), was used in jar-tests to simulate the chemically enhanced primary treatment (CEPT) for municipal wastewater. Removal of particles, organic compounds, nitrogen and phosphorus in wastewater was investigated, and the effects of pH and surface overflow rate (SOR) on flocculation were also examined. Electrical charge and distribution of particles in wastewater were analyzed before and after flocculation. Furthermore, the flocculation mechanism and application of JYF-1 in CEPT were discussed. The results demonstrate that JYF-1 performs better than PAC under a wide pH and SOR range. When 8 mg x L(-1) JYF-1 is added, 76.72% COD and 64.31% soluble COD (SCOD) can be removed. About 90% soluble TP (STP), 80% TP and 20% TN can be removed by addition of 12 mg x L(-1) JYF-1. After flocculation, the BOD/COD ratio increases from 0.23 to 0.53, which indicates the biodegradation ability of wastewater is improved. It can be concluded that JYF-1 is a high-efficiency low-cost flocculant, which can improve outlet water quality and produce less sludge without changing the existing equipments and treating process in sewage plants.


Assuntos
Compostos de Alumínio/química , Cloretos/química , Nitrogênio/química , Fósforo/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Cloreto de Alumínio , Cidades , Floculação , Reprodutibilidade dos Testes , Eliminação de Resíduos Líquidos/economia , Purificação da Água/economia
18.
Anal Bioanal Chem ; 388(3): 723-31, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17447054

RESUMO

The ratios of stable carbon isotopes ((13)C/(12)C) of ganoderma fruiting body, ganoderma spore, ganoderma spore lipid (GSL) and individual fatty acids in GSL were determined by gas chromatography-stable isotope ratio mass spectrometry and elemental analysis-stable isotope ratio mass spectrometry. These values fall into a range from -26.9 to -23.3 per thousand, suggesting that the cut log as the Ganoderma-cultivated substrate in Fujian, China, may belong to C3 plants. Eighteen fatty acids were identified and their abundances measured by gas chromatography-mass spectrometry in the six GSL samples with C(16:0), C(18:0), C(18:1) and C(18:2) as major constituents, and C(16:1) is evidently enriched compared with the other edible vegetable oils. On the basis of the compositions of fatty acids and stable carbon isotopes in GSL, we have developed a novel method to detect the adulteration of GSL products with cheaper edible vegetable oils. An example of ideal blending between GSL and C4 or C3 vegetable oil is further provided to expound the discrimination procedures and corresponding sensitive indicators. Simultaneously, the carbon isotope fractionation in the biosynthesis of individual fatty acids was observed, revealing that the formation of C(18:0) from C(16:0) in ganodema spores had no conspicuous (13)C enrichment of +0.4 per thousand for Ganoderma sinensis spore and +0.1 per thousand for G. lucidum spore; the desaturation of C(18:0) to C(18:1) resulted in a distinct (13)C depletion of -1.4 per thousand for G. sinensis spore and -0.9 per thousand for G. lucidum spore; and the next desaturation from C(18:1) to C(18:2) displayed no evident (13)C fractionation of -0.1 per thousand for G. sinensis spore and -0.2 per thousand for G. lucidum spore.


Assuntos
Ácidos Graxos/análise , Ganoderma/química , Isótopos de Carbono , Ergosterol/análise , Carpóforos , Ganoderma/fisiologia , Cromatografia Gasosa-Espectrometria de Massas , Lipídeos/análise , Esporos Fúngicos/química
19.
Yao Xue Xue Bao ; 37(2): 113-6, 2002 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-12579954

RESUMO

AIM: A series of substituted phenyliminomethylenecoumarins derivatives was designed in order to find compounds possessing anticancer activities. METHODS: Title compounds (1a-b, 2a-b and 3a-q) were synthesized and screened by several anticancer models in vitro. RESULTS: Twenty-one new compounds (1a-b, 2a-b and 3a-q) were synthesized and screened. Structures of the new compunds were determined by MS, HNMR and elemental analysis. Twelve compounds (3c, 3d, 3e, 3f, 3g, 3h, 3j, 3k, 3m, 3o, 3p, 3q) showed inhibitory effects on HCT-8, KB and Bel7402 cell lines in vitro. CONCLUSION: Some compounds had certain anticancer activities and were worth further studying.


Assuntos
Antineoplásicos/síntese química , Cumarínicos/síntese química , Iminas/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/patologia , Neoplasias do Colo/patologia , Cumarínicos/química , Cumarínicos/farmacologia , Humanos , Iminas/química , Iminas/farmacologia , Células KB/efeitos dos fármacos , Neoplasias Hepáticas/patologia , Estrutura Molecular , Células Tumorais Cultivadas/efeitos dos fármacos
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