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1.
Sci Total Environ ; 715: 136805, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32041038

RESUMO

Aryl hydrocarbon receptor (AhR) plays important roles in the interferences of dioxin exposure with the occurrence and development of tumors. Neuroblastoma is a kind of malignant tumor with high mortality and its occurrence is getting higher in dioxin exposed populations. However, there is still a lack of direct evidence of influences of dioxin on neuroblastoma cell migration. SK-N-SH is a human neuroblastoma cell line which has been used to reveal 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced dysregulation of certain promigratory gene. Thus, in this study, we employed SK-N-SH cells to investigate the effects of TCDD on the spontaneous movement of neuroblastoma cells, which is a short-range cell migratory behavior related to clone formation and tumor metastasis in vitro. Using unlabeled live cell imaging and high content analysis, we characterized the spontaneous movement under a full-nutrient condition in SK-N-SH cells. We found that the spontaneous movement of SK-N-SH cells was inhibited after 36- or 48-h treatment with TCDD at relative low concentrations (10-10 or 2 × 10-10 M). The TCDD-treated cells were unable to move as freely as that of control cells, resulting in less diffusive trajectories and a decreased displacement of the movement. In line with this cellular effect, the expression of pro-adhesive genes was significantly induced in time- and concentration-dependent manners after TCDD treatment. In addition, with the presence of AhR antagonist, CH223191, the effects of TCDD on the gene expression and the spontaneous cell movement were effectively reversed. Thus, we proposed that AhR-mediated up-regulation of pro-adhesive genes might be involved in the inhibitory effects of dioxin on the spontaneous movement of neuroblastoma cells. To our knowledge, this is the first piece of direct evidence about the influence of dioxin on neuroblastoma cell motility.

2.
Environ Int ; 136: 105437, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31881423

RESUMO

Toxicity of ZnO nanoparticles (NPs) are often related to the release of Zn2+ ions due to their dissolution. Studies also suggest that the toxicity of ZnO NPs cannot be solely explained by the release of Zn2+ ions; however, there is a lack of direct evidence of ZnO particulate effects. This study compared the acute toxicity of ZnO NPs and ZnSO4 following intranasal exposure using a combination of metallomics and metabolomics approaches. Significant accumulation of Zn in the liver was only found in the ZnO NP treatment, with 29% of the newly accumulated Zn in the form of ZnO as revealed by X-ray fine structure spectroscopy (XAFS). This is the first direct evidence suggesting the persistence of ZnO NPs in liver upon intranasal exposure. Although both ZnO NPs and ZnSO4 altered the metabolite profiles, with some overlaps and considerable specificity, of both liver and plasma samples, more and distinct metabolites in the liver and opposite effects in the plasma were altered by ZnO NPs compared with ZnSO4, consistent with no accumulation of Zn detected in liver from ZnSO4. Specifically, a large number of antioxidant-related compounds and energetic substrates were exclusively elevated in the liver of ZnO NP-treated animals. These findings provided direct evidence that persistence of ZnO NPs induced particle-specific effects on the antioxidant systems and energy metabolism pathways.

3.
Ital J Pediatr ; 45(1): 163, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842954

RESUMO

OBJECTIVES: Mycoplasma pneumoniae is a leading cause of community-acquired pneumonia in children. However, its mechanism of pathogenesis is not fully understood, and microRNAs might play a role. This study aimed to explore the microRNA-222-3p (miR-222-3p) expression and its possible role in children with M.pneumoniae pneumonia (MPP). METHODS: Thirty-six children with MPP and twenty-seven age-matched controls from Children's Hospital of Soochow University were enrolled in this study. MiR-222-3p and cluster of differentiation 4 (CD4) mRNA were detected using real-time PCR in children's peripheral blood plasma samples. THP-1 cells and mice were stimulated with M.pneumoniae lipid-associated membrane proteins(LAMPs). RESULTS: Children with MPP had significantly higher levels of miR-222-3p and lower levels of CD4 in peripheral blood plasma (P <  0.05). Additionally, Sixteen children with MPP complicated with pleural effusion had higher miR-222-3p levels than those without pleural effusion. MiR-222-3p or CD4 in THP-1 cells increased or decreased, respectively, in a dose dependent manner after LAMP stimulation. In LAMP-stimulated mice massive inflammatory cells infiltrates surrounded the bronchioles, and miR-222-3p increased in the bronchoalveolar lavage fluid. In conclusion, miR-222-3p was highly expressed in children with MPP, especially those with pleural effusion. CONCLUSION: Small sample studies showed that M.pneumoniae or its LAMPs could increase miR-222-3p and decrease CD4 in macrophages,both in vitro and vivo.Thus, miR-222-3p might be an MPP biomarker for the diagnosis and prognosis.

4.
Chem Commun (Camb) ; 55(89): 13450-13453, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31647071

RESUMO

Hydroxyl group and pyridinium salt-bifunctionalized nanoporous ionic organic networks prepared via a simple two-step strategy under metal- and template-free conditions are presented. The structural features of the resultant polymer (e.g. high surface area, abundant hydroxyl groups and ionic functionalities) made it a promising candidate as an efficient scavenger of toxic oxo-anions from water.

5.
Ital J Pediatr ; 45(1): 123, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547841

RESUMO

OBJECTIVE: We studied the short-term effects of air pollutant concentrations in Suzhou City on respiratory infections in children of different age groups. METHODS: We employed clinical data from children hospitalized with respiratory infections at the Children's Hospital of Soochow University during 2014-2016, and air quality for Suzhou City covering the same period.We investigated the relationships between the air pollutant concentrations and respiratory tract infections in children by causative pathogen using time series models with lagged effects. RESULTS: The results of single-pollutant models showed that PM2.5, PM10, NO2, SO2 and CO had statistically significant associations with respiratory tract infections in children under 3 years, with the largest effect sizes at a lag of 3 weeks. Notably, the multi-pollutant model found PM2.5 was significantly associated with viral respiratory in children under 7 months, and bacterial respiratory infections in other age groups, while PM10 concentrations were associated with viral infections in preschool children. CONCLUSION: PM2.5, PM10 and NO2 are the main atmospheric pollutants in Suzhou. The associations between pollutant concentrations and viral and bacterial respiratory infections were stronger among children under 3 years than for older age group.s PM2.5 had the strongest influence on viral and Mycoplasma pneumoniae respiratory infections when multiple pollutants were tested together.

6.
Med Sci Monit ; 25: 4110-4121, 2019 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-31154455

RESUMO

BACKGROUND The tumor microenvironment in lung cancer plays an important role in tumor progression and metastasis. Bone marrow-derived mesenchymal stem cells (MSCs) co-cultured with A549 lung cancer cells show changes in morphology, increase cell proliferation, and cell migration. This study aimed to investigate the effects of Astragalus polysaccharide (APS), a traditional Chinese herbal medicine, on the changes induced in bone marrow-derived MSCs by A549 lung cancer cells in vitro. MATERIAL AND METHODS Bone marrow-derived MSCs were co-cultured with A549 cells (Co-BMSCs). Co-cultured bone marrow-derived MSCs and A549 cells treated with 50 µg/ml of APS (Co-BMSCs + APS) were compared with untreated Co-BMSCs. Cell proliferation was measured using the cell counting kit-8 (CCK-8) assay. Flow cytometry evaluated the cell cycle. Microarray assays for mRNA expression and Western blot for protein expression were used. RESULTS Compared with untreated Co-BMSCs, APS treatment of Co-BMSCs improved cell morphology, reduced cell proliferation, and inhibited cell cycle arrest. The mitogen-activated protein kinase (MAPK)/nuclear factor-kappa B (NF-kappaB) pathway, TP53, caspase-3, acetylated H4K5, acetylated H4K8, and acetylated H3K9 were involved in the regulatory process. CONCLUSIONS APS treatment reduced cell proliferation and morphological changes in bone marrow-derived MSCs that were co-cultured with A549 lung cancer cells in vitro.


Assuntos
Células A549/efeitos dos fármacos , Astrágalo (Planta)/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medula Óssea/metabolismo , Células da Medula Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , China , Técnicas de Cocultura , Humanos , Neoplasias Pulmonares/metabolismo , Medicina Tradicional Chinesa/métodos , Células-Tronco Mesenquimais/efeitos dos fármacos , Polissacarídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
7.
Chem Biol Interact ; 309: 108686, 2019 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-31152735

RESUMO

Acetylcholinesterase (EC3.1.1.7; AChE) is a key enzyme in the cholinergic system. Emerging evidence has shown that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a typical persistent organic pollutant, suppressed neuronal AChE activity via dysregulation of different biosynthesis processes in human and rat neuronal cells. In the nervous system, astrocytes protect neurons from environmental pollutants. As a known target cell of TCDD, the astrocyte might be involved in TCDD effects on neuronal AChE. Therefore, in the present study, we found astrocyte-derived conditioned medium (ACM) could induce AChE activity preferentially in mature neurons in the absence of TCDD. The enzymatic activity of AChE was generally decreased in cultured cortical neurons upon direct treatment with TCDD (0.003-0.01 nM). This trend of changes in AChE activity was not significantly altered in immature neurons exposed to ACM produced in the presence of TCDD (TACM group), but reversed in mature neurons. Compared with effects of treatment with ACM plus TCDD (ACMT), a significant differential effect on AChE activity was found in the TACM group in response to TCDD treatment specifically in immature neurons, suggesting the presence of a TCDD-specific active component derived from the astrocyte. Inconsistent alterations in expression and enzymatic activities of the AChE T subunit (AChET) and the proline-rich membrane anchor (PRiMA) were found, suggesting that a mechanism of action beyond the transcriptional level might be involved. These data indicate that the astrocyte might play a protective role in TCDD-induced alterations of neuronal AChE in certain stages of differentiation.


Assuntos
Acetilcolinesterase/metabolismo , Meios de Cultivo Condicionados/química , Expressão Gênica/efeitos dos fármacos , Dibenzodioxinas Policloradas/farmacologia , Acetilcolinesterase/genética , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Dibenzodioxinas Policloradas/química , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
8.
Chem Biol Interact ; 308: 164-169, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31100272

RESUMO

Emerging data indicate that prenatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) could interfere with myogenic differentiation in vivo. Acetylcholinesterase (EC3.1.1.7; AChE), an enzyme critical for cholinergic neurotransmission, is abundantly expressed in neurons and mature myotubes, and we recently found that muscle AChE expression was suppressed in parallel with the inhibition of myogenic differentiation upon TCDD treatment in mouse C2C12 cells. This TCDD-induced suppression of muscle AChE was proposed to involve an aryl hydrocarbon receptor (AhR)-independent mechanism, but the precise underlying mechanism remains unclear. Considering the widely recognized role of muscular activity in AChE expression and its potential crosstalk with the AhR signaling pathway, we sought to investigate the effect of TCDD on muscle AChE expression in the presence of muscular activity. Therefore, we employed a highly contractile rat primary skeletal muscle culture system in which AChE activity and the expression of genes related to it (AChE T subunit and collagen Q (ColQ)) were increased during the myogenic differentiation process. Although TCDD treatment successfully induced the expression of genes regulated by AhR activation, the treatment exerted no notable effects on myogenic differentiation. Moreover, muscle AChE enzymatic activity and mRNA level remained unchanged following TCDD treatment, and only ColQ mRNA expression was slightly increased after 4-day treatment with TCDD (10-10 M). The compensatory role of muscle-contraction-related signaling pathways in this newly identified unresponsiveness of muscle AChE to TCDD warrants further investigation.


Assuntos
Acetilcolinesterase/metabolismo , Diferenciação Celular/efeitos dos fármacos , Desenvolvimento Muscular/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Acetilcolinesterase/genética , Animais , Células Cultivadas , Colágeno/genética , Colágeno/metabolismo , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Contração Muscular/efeitos dos fármacos , Mioblastos Esqueléticos/citologia , Mioblastos Esqueléticos/efeitos dos fármacos , Mioblastos Esqueléticos/metabolismo , Dibenzodioxinas Policloradas/metabolismo , Ratos , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos
9.
Environ Int ; 121(Pt 1): 906-915, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30347373

RESUMO

Autism spectrum disorder (ASD) has emerged as a major public health concern due to its fast-growing prevalence in recent decades. Environmental factors are thought to contribute substantially to the variance in ASD. Interest in environmental toxins as causes of ASD has arisen due to the high sensitivity of the developing human brain to toxic chemicals, particularly to dioxin and certain dioxin-like compounds (dioxins). As a group of typical persistent organic pollutants, dioxins have been found to exert adverse effects on human brain development. In this paper, we review the evidence for association of exposure to dioxins with neurodevelopmental abnormalities related to ASD based on both human epidemiological and animal studies. It has been documented that exposure to dioxins during critical developmental periods increased risk for ASD. This notion has been demonstrated in different populations exposed to high or background level of dioxins. Furthermore, the effects and mechanisms of action of dioxins relevant to the pathophysiology and pathogenesis of ASD are summarized, describing potential underlying mechanisms linking dioxin exposure with ASD onset. Further studies focusing on effects of prenatal/perinatal exposure to individual dioxin congeners or to mixtures of dioxins on ASD-associated behavioral and neurobiological consequences in animal models, and on the mechanisms of actions of dioxins, are needed in order to better understand how dioxin exposure might contribute to increased risk for ASD.


Assuntos
Transtorno do Espectro Autista/epidemiologia , Dioxinas/toxicidade , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidade , Animais , Humanos , Fatores de Risco
10.
Med Sci Monit ; 24: 4649-4658, 2018 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-29976920

RESUMO

BACKGROUND This study investigated the effect of Astragalus polysaccharides (APS) on radiation-induced bystander effects (RIBE) in human bone mesenchymal stem cells (BMSCs) induced by irradiated A549 cells. MATERIAL AND METHODS A549 cells were irradiated with 2 Gy X-rays to obtain conditioned medium. BMSCs were incubated with the conditioned medium or APS. The levels of reactive oxygen species (ROS) and TGF-ß were detected by ELISA. Cell survival, genomic instability, and DNA damages were detected by CCK-8 assay, colony formation assay, the micronucleus test and immunofluorescence assay, respectively. The protein and phosphorylation protein expression of p38, c-Jun N-terminal kinase (JNK), extracellular regulated protein kinase (ERK1/2), P65, and cyclooxygenase-2 (COX-2) in bystander effect cells were detected by Western blot. RESULTS The expression of COX-2 and ROS increased following stimulation with conditioned medium; this effect was inhibited by pre-exposing the cells to APS. BMSCs growth and colony formation rate decreased following stimulation with conditioned medium; this effect was suppressed by pre-exposing the cells to APS. In addition, the micronucleus rate and 53BP1 foci number increased after treatment with conditioned medium; this increase in BMSCs was inhibited by APS. The levels of phosphorylated p38, JNK, ERK1/2, NF-κB P65, and COX-2 proteins were increased by conditioned medium but were decreased by pre-treatment with APS. CONCLUSIONS RIBE in BMSCs induced by the irradiated A549 was mediated by the ROS in the conditioned medium and might be related to MAPK/NF-κB signal pathways in BMSCs. APS may block RIBE through regulating the MAPK/NF-κB pathway.


Assuntos
Células A549/efeitos dos fármacos , Astrágalo (Planta)/metabolismo , Efeito Espectador/efeitos dos fármacos , Células A549/metabolismo , Osso e Ossos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Polissacarídeos/farmacologia , Radiação Ionizante , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo
11.
Environ Pollut ; 235: 965-973, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29751400

RESUMO

Dioxin-induced toxicities that affect the development of the motor system have been proposed since many years. However, cellular evidence and the molecular basis for the effects are limited. In this study, a cultured mouse myoblast cell line, C2C12, was utilized to examine the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on myogenic differentiation and expression of acetylcholinesterase (AChE), a neuromuscular transmission-related gene. The results showed that TCDD exposure at 10-10 M repressed the myotube formation of C2C12 cells by disturbing the fusion process and suppressing the expression of myosin heavy chain, a myobute structural protein, and not by induction of cytotoxicity. Furthermore, TCDD dose dependently suppressed the transcriptional expression and enzymatic activity of AChE during the myogenic differentiation, particularly in the middle stage. However, the administration of aryl hydrocarbon receptor antagonists, CH223191 and alpha-naphthoflavone, did not completely reverse the TCDD-induced downregulation of muscular AChE during myogenic differentiation. These findings suggest that low dose exposure to dioxin may result in disturbances of muscle differentiation and neuromuscular transmission.


Assuntos
Substâncias Perigosas/toxicidade , Dibenzodioxinas Policloradas/toxicidade , Animais , Compostos Azo , Benzoflavonas , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Camundongos , Pirazóis , Receptores de Hidrocarboneto Arílico/metabolismo
12.
Exp Ther Med ; 14(4): 2983-2991, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28966680

RESUMO

The initiation and progression of various types of tumors, such as lung neoplasms, are driven by a population of cells with stem cell properties and their microenvironment. Bone marrow mesenchymal stem cells (BM-MSCs) in long-term in vitro culture may exhibit spontaneous changes in stem cell biological properties, including malignant transformations; however, the molecular mechanisms of this have not been fully elucidated. In the present study, a BM-MSC and lung cancer A549 cell co-culture system was utilized to investigate how the tumor microenvironment may spontaneously change the proliferation, migration and differentiation of BM-MSCs. It was demonstrated that the lung cancer A549 microenvironment is able to induce changes in the cell morphology, proliferation, karyotype, cytoskeleton and migration ability of BM-MSCs in vitro. Compared with the control group BM-MSCs, the expression of Ras, phosphorylated-extracellular regulated protein kinases, nuclear factor-κB, P62 and B-cell lymphoma 2 (Bcl-2) proteins in groups of co-cultured BM-MSCs increased significantly (P<0.05) and the expression of P53, Bcl-2 associated X protein and caspase-3 protein decreased significantly (P<0.05). The mechanisms responsible for the changes observed in BM-MSCs may be related to abnormal expression of related genes in the ERK signaling pathway.

13.
Chem Commun (Camb) ; 53(14): 2241-2244, 2017 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-28144645

RESUMO

A system of controllable capture and release of protein was constructed by multiple, interconnected supramolecular binding modules based on lactose modified mono-cationic perylene bisimide derivatives, cucurbit[8]uril (CB[8]), 1-adamantanamine (ADA) and peanut agglutinin (PNA) lectins.


Assuntos
Imidas/química , Aglutinina de Amendoim/metabolismo , Perileno/análogos & derivados , Hidrocarbonetos Aromáticos com Pontes/química , Cátions/química , Imidazóis/química , Lactose/química , Espectroscopia de Ressonância Magnética , Nefelometria e Turbidimetria , Aglutinina de Amendoim/química , Perileno/química , Espectrometria de Fluorescência
14.
Vaccine ; 34(36): 4285-92, 2016 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-27423383

RESUMO

Lipopolysaccharide (LPS) O-antigen and enterobacterial common antigen (ECA) are two major polysaccharide structures on the surface of Salmonella enterica serovar Typhimurium. Previous studies have demonstrated that regulated truncation of LPS enhances the cross-reaction against conserved outer membrane proteins (OMPs) from enteric bacteria. We speculate that the regulation of both O-antigen and ECA may enhance the induction of immune responses against conserved OMPs from enteric bacteria. In this work we targeted rfbB and rffG genes which encode dTDP-glucose 4,6-dehydratases and share the same function in regulating O-antigen and ECA synthesis. We constructed a mutant, S496 (ΔrfbB6 ΔrffG7 ΔpagL73::TT araC PBADrfbB-3), in which rfbB gene expression was dependent on exogenously supplied arabinose during in vitro growth and achieved the simultaneous tight regulation of both LPS and ECA synthesis, as demonstrated by the LPS profile and Western blotting using antisera against LPS and ECA. When administered orally, S. Typhimurium S496 was completely attenuated for virulence but still retained the capacity to colonize and disseminate in mice. In addition, we found that oral immunization with S496 resulted in increased immune responses against OMPs from enteric bacteria and enhanced survival compared with immunization with S492 possessing ΔrfbB6 ΔrffG8 mutations when challenged with lethal doses of Salmonella Choleraesuis or Salmonella Enteritidis. These results indicate that S. Typhimurium arabinose-regulated rfbB strain S496 is a good vaccine candidate, conferring cross-protection against lethal challenge with heterologous Salmonella.


Assuntos
Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Antígenos O/genética , Salmonelose Animal/imunologia , Vacinas contra Salmonella/imunologia , Salmonella typhimurium/genética , Salmonella typhimurium/imunologia , Administração Oral , Animais , Anticorpos Antibacterianos , Antígenos de Bactérias/biossíntese , Antígenos de Bactérias/imunologia , Arabinose/farmacologia , Proteínas da Membrana Bacteriana Externa/química , Proteínas de Bactérias/genética , Proteção Cruzada , Regulação Bacteriana da Expressão Gênica , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Antígenos O/biossíntese , Antígenos O/imunologia , Salmonelose Animal/microbiologia , Salmonelose Animal/prevenção & controle , Vacinas contra Salmonella/administração & dosagem , Salmonella enterica/imunologia , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/enzimologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia
15.
Microb Pathog ; 91: 99-106, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26706345

RESUMO

Riemerella anatipestifer (R. anatipestifer) causes severe perihepatitis, pericarditis, airsacculitis and meningitis in the duck, leading to great economic losses worldwide. Given the increased prevalence of drug-resistance strains, vaccination is the best strategy to prevent R. anatipestifer infection in ducklings. In this study, we identified a gene in R. anatipestifer (B739-2187) that can restore the resistance of the Salmonella phoP mutant to polymyxin B using genetic complementation. Furthermore, the deletion of B739-2187 in R. anatipestifer resulted in a mutant exhibiting increased sensitivity to polymyxin B. The R. anatipestifer B739-2187 mutant did not exhibit phenotypic defects, as indicated by its growth curve, lipopolysaccharide and outer membrane protein profiles, and attachment and invasion of duck embryo fibroblast cells. The duck animal experiments demonstrated that the deletion of B739-2187 significantly decreased the virulence of R. anatipestifer, and the B739-2187 mutant provided 100% protection against challenge with wild-type R. anatipestifer, exhibiting the characteristics of an ideal live vaccine.


Assuntos
Proteínas de Bactérias/imunologia , Farmacorresistência Bacteriana , Infecções por Flavobacteriaceae/veterinária , Polimixina B/farmacologia , Doenças das Aves Domésticas/imunologia , Riemerella/imunologia , Vacinas Atenuadas/imunologia , Animais , Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/genética , Patos , Feminino , Infecções por Flavobacteriaceae/microbiologia , Infecções por Flavobacteriaceae/prevenção & controle , Deleção de Genes , Masculino , Mutação , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Riemerella/efeitos dos fármacos , Riemerella/genética , Riemerella/patogenicidade , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Virulência
16.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 35(4): 450-6, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-26043569

RESUMO

OBJECTIVE: To study the effect of ultrafiltration-membrane extracts of Radix Rehmanniae Praeparata (UMERRP) on theproliferation and genetic stability of bone marrow-derived mesenchymal stem cells (BMSCs) induced by cadmium chloride (CdCl2). METHODS: Protective effects on the proliferation, micronuclear rates, chromosome aberration rates, and apoptosis rates were observed by micronuclei test, karyotype analysis, and flow cytometry. RESULTS: Compared with the CdCl2 group, UMERRP with different molecular weights at 0. 8 g/L could obviously promote the proliferation (P <0. 05). Compared with the control group, micronuclear rates, chromosome aberration rates, and apoptosis rates were obviously enhanced in the CdCl2 group (P <0. 05). Compared with the CdCl2 group, UMERRP with different molecular weights could obviously decreased CdCl2 induced micronuclear rates, chromosome aberration rates, and apoptosis rates (P <0. 05). Of them, BMSC micronuclear rates and chromosome aberration rates decreased most obvious in UMERRP groups with molecular weight below 10 000 (P <0. 05). The apoptosis rate decreased most obviously in UMERRP groups with molecular weight ranging 100 000 and 200 000 (P <0. 05). CONCLUSION: UMERRP could reduce CdCl2 induced micronuclear rates, chromosome aberration rates, and apoptosis rates.


Assuntos
Cloreto de Cádmio/toxicidade , Medicamentos de Ervas Chinesas/farmacologia , Células-Tronco Mesenquimais , Apoptose , Medula Óssea , Citometria de Fluxo , Células-Tronco Hematopoéticas , Humanos , Ultrafiltração
17.
Food Chem ; 171: 168-76, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25308657

RESUMO

The impacts of freeze drying (FD), hot-air drying (AD), and heat pump drying (HPD) on myosin structure, amino acid composition, protein digestibility and volatile compounds of squid (Todarodes pacificus) fillets were evaluated. Freeze-dried squids showed similar amino acid composition to that of raw squids, but differed from that of AD and HPD samples. The percentage of in vitro digestibility followed the order of FD (76.81%)>HPD (70.51%)>raw (67.99%)>AD (61.47%) samples. AD caused more damage to squid myosin structure than HPD, while FD effectively retained the myosin integrity. Drying decreased total number of volatile compounds, but increased the content of total volatile compounds based on GC × GC-TOFMS results. HPD and AD samples had the highest and lowest total numbers and contents of volatiles, respectively. In general, FD provided squids with the best quality, followed by HPD. Considering the production cost and product quality, HPD demonstrated the potential for industrial application.


Assuntos
Aminoácidos/química , Dessecação/métodos , Liofilização/métodos , Miosinas/química , Proteínas/química , Alimentos Marinhos , Animais , Antioxidantes/química , Dicroísmo Circular , Decapodiformes , Conservação de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Análise dos Mínimos Quadrados , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Triptofano/química
18.
Asian Pac J Cancer Prev ; 15(5): 2169-77, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24716952

RESUMO

Matrine, a main active component extracted from dry roots of Sophora flavecens , has been reported to exert antitumor effects on A549 human non-small lung cancer cells, but its mechanisms of action remain unclear. To determine effects of matrine on proliferation of A549 cells and assess possible mechanisms, MTT assays were employed to detect cytotoxicity, along with o flow cytometric analysis of DNA content of nuclei of cells following staining with propidium iodide to analyze cell cycle distribution. Western blotting was performed to determined expression levels of Bax, Bcl-2, VEGF and HDAC1, while a microarray was used to assessed changes of miRNA profiles. In the MTT assay, matrine suppressed growth of human lung cancer cell A549 in a dose- and time- dependent manner at doses of 0.25-2.5 mg/ml for 24h, 48h or 72h. Matrine induced cell cycle arrest in G0/G1 phase and decreased the G2/M phase, while down-regulating the expression of Bcl2 protein, leading to a reduction in the Bcl-2/Bax ratio. In addition, matrine down regulated the expression level of VEGF and HDAC1 of A549 cells. Microarray analysis demonstrated that matrine altered the expression level of miRNAs compared with untreated control A549 cells. In conclusion, matrine could inhibit proliferation of A549 cells, providing useful information for understanding anticancer mechanisms.


Assuntos
Alcaloides/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , MicroRNAs/genética , Quinolizinas/farmacologia , Transcriptoma/efeitos dos fármacos , Antineoplásicos/farmacologia , Apoptose/genética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Histona Desacetilase 1/genética , Humanos , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Transcriptoma/genética , Fator A de Crescimento do Endotélio Vascular/genética , Proteína X Associada a bcl-2/genética
19.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(3): 295-300, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24661525

RESUMO

OBJECTIVE: To observe the changes in anxiety-like behavior among rats in the recovery stage after hypoxic-ischemic brain damage (HIBD) during the perinatal period and to investigate the effect of insulin-like growth factor 1 (IGF-1) on the long-term anxiety-like behavior and its action mechanism among rats with HIBD. METHODS: Ninety neonatal rats (7 days old) were randomly and equally divided into normal control, HIBD, and HIBD+IGF-1 groups. A neonatal rat model of HIBD was established by Rice method in the HIBD and HIBD+IGF-1 groups. The rats in the HIBD+IGF-1 group were intraperitoneally injected with IGF-1 (0.2 mg/kg) immediately after HIBD, and the other two groups were intraperitoneally injected with an equal volume of normal saline. The anxiety-like behavior was evaluated by elevated plus-maze test on postnatal days 21 and 28. The expression of tyrosine hydroxylase (TH) in the substantia nigra was measured by immunohistochemistry on postnatal days 14, 21, and 28. RESULTS: On postnatal days 21 and 28, the open-arm time (OAT) and percentage of OAT for the HIBD and HIBD+IGF-1 groups were significantly lower than those for the normal control group (P<0.05), but there were no significant differences between the HIBD and HIBD+IGF-1 groups (P>0.05); the percentage of open arm entry showed no significant difference between the three groups (P>0.05). On postnatal day 14, there were no significant differences in percentage of TH immunostaining-positive area between the three groups (P>0.05). On postnatal days 21 and 28, the HIBD and HIBD+IGF-1 groups had significantly lower percentages of TH immunostaining-positive area than the normal control group (P<0.05), but there was no significant difference between the HIBD and HIBD+IGF-1 groups (P>0.05). CONCLUSIONS: HIBD in the perinatal period may cause the changes in anxiety-like behavior in adolescent rats, which may be related to decreased expression of TH in the substantia nigra. Neonatally given IGF-1 cannot improve the long-term anxiety-like behavior in rats after HIBD, and it does not affect TH expression in the substantia nigra. IGF-1 may not regulate the changes in long-term anxiety-like behavior in adolescent rats.


Assuntos
Ansiedade/tratamento farmacológico , Hipóxia-Isquemia Encefálica/psicologia , Fator de Crescimento Insulin-Like I/uso terapêutico , Animais , Animais Recém-Nascidos , Feminino , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Tirosina 3-Mono-Oxigenase/análise
20.
Macromol Rapid Commun ; 34(6): 471-84, 2013 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-23362134

RESUMO

Hypercrosslinked polymers (HCPs) are currently receiving great interest due to their easy preparation, high chemical and thermal stability, and low cost. Combined with the lightweight properties and high surface areas HCPs can be considered as promising materials for gas storage and separation, catalysis, and heavy metal ions removal in wastewater treatment. This Feature Article summarizes strategies for the preparation of HCPs, comprising the post-crosslinking of "Davankov-type" resins, direct polycondensation of aromatic chloromethyl (or hydroxymethyl) monomers, and knitting aromatic compound polymers (KAPs). The HCPs applications, such as H2 storage, CO2 capture, and heterogeneous catalysis, are also discussed throughout in the article. Finally, the outlook of this research area is given.


Assuntos
Dióxido de Carbono/química , Hidrogênio/química , Polímeros/química , Adsorção , Catálise , Porosidade , Propriedades de Superfície
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