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1.
Anaerobe ; 56: 116-123, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30849459

RESUMO

Clostridioides difficile is a colonizer of the human gut; asymptomatic colonization has been reported to be more common in infants and is highly variable across regions even with no symptoms of diarrhea or death. Antibiotic treatment strategies might increase the antibiotic resistance of C. difficile. We performed a one-point study involving 1098 healthy infants (0-36 months) to address the deficiency of reports on C. difficile colonization in Chinese community infants. The C. difficile colonization rate was 22.8% (250/1098), and more than half of the strains (55.2%) were toxigenic isolates. Among the 138 toxigenic isolates, 111 were of the A+B+CDT- genotype, 26 strains were A-B+CDT-, and one strain was A+B+CDT+. Fifteen different PCR ribotypes were found among the 250 isolates, and PCR-ribotype HB03 appeared to be dominant type, accounting for 19.6% (49/250). High levels of resistance to antimicrobial agents were observed. Our study showed that age and hospitalization before stool collection were positively correlated with the C. difficile colonization rate, whereas the delivery term was negatively related to the colonization rate. Particular attention should be paid to the increasing resistance of C. difficile to rifamycin.


Assuntos
Portador Sadio/epidemiologia , Infecções por Clostridium/epidemiologia , Clostridium difficile/isolamento & purificação , Grupo com Ancestrais do Continente Asiático , Toxinas Bacterianas/genética , Portador Sadio/microbiologia , China/epidemiologia , Infecções por Clostridium/microbiologia , Genótipo , Voluntários Saudáveis , Humanos , Lactente , Epidemiologia Molecular , Reação em Cadeia da Polimerase , Prevalência , Ribotipagem
2.
Front Immunol ; 10: 169, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30814995

RESUMO

The long-term persistence of viral antigens drives virus-specific CD8 T cell exhaustion during chronic viral infection. Yet exhausted, CD8 T cells are still endowed with certain levels of effector function, by which they can keep viral replication in check in chronic infection. However, the regulatory factors involved in regulating the effector function of exhausted CD8 T cell are largely unknown. Using mouse model of chronic LCMV infection, we found that the deletion of transcription factor TCF-1 in LCMV-specific exhausted CD8 T cells led to the profound reduction in cytokine production and degranulation. Conversely, ectopic expression of TCF-1 or using agonist to activate TCF-1 activities promotes the effector function of exhausted CD8 T cells. Mechanistically, TCF-1 fuels the functionalities of exhausted CD8 T cells by promoting the expression of an array of key effector function-associated transcription regulators, including Foxo1, Zeb2, Id3, and Eomes. These results collectively indicate that targeting TCF-1 mediated transcriptional pathway may represent a promising immunotherapy strategy against chronic viral infections by reinvigorating the effector function of exhausted virus-specific CD8 T cells.

3.
Cell Mol Immunol ; 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30842630

RESUMO

Epigenetic modifications to histones dictate the differentiation of naïve CD4+ T cells into different subsets of effector T helper (TH) cells. The histone methyltransferase enhancer of zeste homolog 2 (EZH2) has been implicated in the mechanism regulating the differentiation of TH1, TH2 and regulatory T (Treg) cells. However, whether and how EZH2 regulates follicular helper T (TFH) cell differentiation remain unknown. Using a mouse model of acute lymphocytic choriomeningitis virus (LCMV) infection, we observed abundant EZH2 expression and associated H3K27me3 modifications preferentially in the early committed virus-specific TFH cells compared to those in TH1 cells. Ablation of EZH2 in LCMV-specific CD4+ T cells leads to a selective impairment of early TFH cell fate commitment, but not late TFH differentiation or memory TFH maintenance. Mechanistically, EZH2 specifically stabilizes the chromatin accessibility of a cluster of genes that are important for TFH fate commitment, particularly B cell lymphoma 6 (Bcl6), and thus directs TFH cell commitment. Therefore, we identified the chromatin-modifying enzyme EZH2 as a novel regulator of early TFH differentiation during acute viral infection.

4.
Int J Oncol ; 54(1): 315-325, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30387841

RESUMO

MicroRNAs (miRNAs/miRs) are widely dysregulated in papillary thyroid cancer (PTC). Dysregulated miRNAs, together with their target genes, comprise a complex network that has been implicated in the regulation of PTC pathogenesis. Further knowledge of the functional roles of aberrantly expressed miRNAs in PTC, and the underlying molecular mechanisms, may assist in the identification of novel therapeutic targets. miR­766 has been well studied in human cancer; however, the expression status, specific roles and regulatory mechanisms of miR­766 in PTC remain unclear. The present study aimed to detect miR­766 expression in PTC tissues and cell lines, to explore the biological roles of miR­766 in the malignant biological behaviors of PTC cells, and to determine the underlying mechanism of action of miR­766 in PTC cells. The results revealed that miR­766 was downregulated in PTC tissues and cell lines, and its downregulation was strongly associated with TNM stage and lymph node metastasis. Overexpression of miR­766 inhibited PTC cell proliferation, colony formation, migration and invasion, promoted cell apoptosis and reduced tumor growth in vivo. Mechanistically, insulin receptor substrate 2 (IRS2) was identified as a direct target of miR­766 in PTC cells. IRS2 was upregulated in PTC tissues, and this was inversely correlated with miR­766 expression. Inhibition of IRS2 simulated the tumor suppressor activity of miR­766 in PTC cells. Restoration of IRS2 expression negated the tumor­suppressing effects of miR­766 overexpression on PTC cells. Notably, miR­766 directly targeted IRS2 to inhibit activation of the phosphoinositide 3­kinase (PI3K)/protein kinase B (Akt) pathway in PTC cells in vitro and in vivo. Overall, these findings indicated that miR­766 may inhibit the malignant biological behaviors of PTC cells by directly targeting IRS2 and regulating the PI3K/Akt pathway, thus suggesting that this miRNA may be a promising therapeutic target for PTC.


Assuntos
Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , MicroRNAs/genética , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Regiões 3' não Traduzidas , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Estadiamento de Neoplasias , Transplante de Neoplasias , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/metabolismo , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo
5.
Drug Des Devel Ther ; 12: 3563-3571, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30464390

RESUMO

Objective: Lobaplatin shows antitumor activity against a wide range of tumors, including metastatic breast cancer (BCa). The overexpression of metadherin (MTDH) is associated with poor prognosis of BCa patients. This study was designed to investigate the effect of lobaplatin on MCF-7 cell proliferation and its association with MTDH expression. Patients and methods: Clinical treatment for BCa using lobaplatin, in combination with other general chemotherapy drugs, was administered to 32 BCa patients. The safety, effectiveness, and prognosis in lobaplatin-treated BCa patients were compared with those in controls (n=32). In vitro experiments were performed in MCF-7 cells to investigate the effect of lobaplatin on cell proliferation, apoptosis, and MTDH expression. Results: We found the intraoperative local chemotherapy using lobaplatin was safe and effective for BCa treatment, in comparison with the patients administered general chemotherapy drugs. Treatment of MCF-7 cell cultures with lobaplatin significantly reduced cell proliferation and increased cell apoptotic percentage. The expression of MTDH and Bcl-2 was inhibited by lobaplatin and that of Bax was increased by lobaplatin. Moreover, we observed the inhibition of MTDH by shRNA reduced cell proliferation and enhanced cell apoptosis. Conclusion: Lobaplatin was a safe and effective adjuvant chemotherapy for BCa. The effect of lobaplatin on inhibiting MCF-7 cell proliferation and inducing cell apoptosis might be, as least in part, mediated by suppressing the expression of oncogene MTDH.

6.
Front Immunol ; 9: 1127, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29875775

RESUMO

Follicular helper CD4+ T (TFH) cells are critical for optimal B-cell-mediated humoral immunity by initiating, fueling, and sustaining germinal center reactions. The differentiation of TFH cells relies on multiple intrinsic and extrinsic factors; however, the details by which these factors are integrated to coordinate TFH differentiation are largely unknown. In this study, using a mouse model of acute lymphocytic choriomeningitis virus (LCMV) viral infection, we demonstrate that mTOR complex 2 (mTORC2) kinase integrates TCR signaling and ICOS-mediated co-stimulation to promote late differentiation and functional maturation of virus-specific TFH cells. Specifically, mTORC2 functions to maintain TFH lineage specifications, including phenotypes, migratory characteristics, and functional properties. Thus, our results highlight the importance of mTORC2 in guarding TFH phenotypic and functional maturation.

7.
Methods Mol Biol ; 1707: 15-38, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29388097

RESUMO

B cell responses play a central role in humoral immunity, which protects an individual from invading pathogens by antigen-specific antibodies. Understanding the basic principles of the B cell responses during viral infection is of substantial importance for anti-viral vaccine development. In inbred mice, lymphocytic choriomeningitis virus (LCMV) infection elicits robust and typical T cell-dependent B cell responses, including germinal center reaction, memory B cell formation, and a long-lived plasma cell pool in bone marrow. Therefore, this system represents an ideal model to investigate anti-viral B cell responses. In this protocol, we describe how to propagate and quantify LCMV and successfully establish an acute LCMV infection in mice. This protocol also provides three different techniques to analyze B cell responses specific to an acute LCMV infection: the identification of germinal center (GC) B cells and follicular helper CD4 T (TFH) cells from the spleens and lymph nodes via flow cytometry, titration of LCMV-specific IgG in the serum after LCMV infection using an enzyme-linked immunosorbent assay (ELISA) analysis, and detection of LCMV-IgG secreted plasma cells from bone marrow with an enzyme-linked immunospot (ELISPOT) assay.


Assuntos
Anticorpos Antivirais/imunologia , Células da Medula Óssea/imunologia , Imunoglobulina G/imunologia , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Plasmócitos/imunologia , Animais , Células da Medula Óssea/patologia , Ensaio de Imunoadsorção Enzimática/métodos , Citometria de Fluxo/métodos , Coriomeningite Linfocítica/patologia , Camundongos , Plasmócitos/patologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/patologia
8.
J Clin Microbiol ; 56(5)2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29467194

RESUMO

Clostridium difficile multilocus sequence type 37 (ST37), which mainly corresponds to ribotype 017, has been a dominant genotype circulating in China. In this study, we report the use of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to analyze and characterize 204 C. difficile clinical isolates, including 49 ST37 and 155 non-ST37 isolates collected in China and other countries. The distributions of two major protein peaks (m/z 3,242 and 3,286) were significantly different between ST37 and non-ST37 prototype strains and clinical isolates. This difference was reproducible when analysis was performed on different colonies in different runs. This finding was repeated and confirmed by both bioMérieux Vitek MS and Bruker Microflex LT systems on isolates recovered from a variety of geographic regions worldwide. The combination of the two peaks was present in 47 of 49 ST37 isolates, resulting in a sensitivity of 95.9%. In contrast, the peak combination was absent in 153 of 155 non-ST37 isolates, resulting in a specificity of 98.7%. Our results suggest that MALDI-TOF MS is a rapid and reliable tool to identify C. difficile genotype ST37. Work is in progress to characterize the two molecules having peaks at m/z 3,242 and 3,286, which appear to be specific to C. difficile genotype ST37.

9.
J Microbiol Methods ; 147: 50-55, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29486225

RESUMO

Clostridium difficile is the causative pathogen for antibiotic-related nosocomial diarrhea. For epidemiological study and identification of virulent clones, a new binary typing method was developed for C. difficile in this study. The usefulness of this newly developed optimized 10-loci binary typing method was compared with two widely used methods ribotyping and multilocus sequence typing (MLST) in 189 C. difficile samples. The binary typing, ribotyping and MLST typed the samples into 53 binary types (BTs), 26 ribotypes (RTs), and 33 MLST sequence types (STs), respectively. The typing ability of the binary method was better than that of either ribotyping or MLST expressed in Simpson Index (SI) at 0.937, 0.892 and 0.859, respectively. The ease of testing, portability and cost-effectiveness of the new binary typing would make it a useful typing alternative for outbreak investigations within healthcare facilities and epidemiological research.

10.
J Phys Chem Lett ; 8(22): 5548-5554, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-29083901

RESUMO

Nonphotochemical quenching mechanisms regulate light harvesting in oxygenic photosynthesis. Measurement techniques for nonphotochemical quenching have typically focused on downstream effects of quenching, such as measuring reduced chlorophyll fluorescence. Here, to directly measure a species involved in quenching, we report snapshot transient absorption (TA) spectroscopy, which rapidly tracks carotenoid radical cation signals as samples acclimate to excess light. The formation of zeaxanthin radical cations, which is possible evidence of zeaxanthin-chlorophyll charge-transfer (CT) quenching, was investigated in spinach thylakoids. Together with fluorescence lifetime snapshot data and time-resolved high-performance liquid chromatography (HPLC) measurements, snapshot TA reveals that Zea•+ formation is closely related to energy-dependent quenching (qE) in nonphotochemical quenching. Quantitative and dynamic information on CT quenching discussed in this work give insight into the design principles of photoprotection in natural photosynthesis.


Assuntos
Complexos de Proteínas Captadores de Luz/química , Fotossíntese , Tilacoides/química , Zeaxantinas/química , Carotenoides , Cátions , Clorofila/química , Fluorescência , Luz , Análise Espectral , Spinacia oleracea , Xantofilas
11.
Oncol Rep ; 37(6): 3581-3589, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28498478

RESUMO

In breast cancer (BC), silencing of miRNA genes due to miRNA gene promoter methylation are the important mechanisms directly contributing to tumorigenesis and tumor progression. miRNA-495 (miR-495) has been reported to be a tumor suppressor gene in various cancers, but its role and regulation in BC remains unclear. In the present study, the level of miR-495 was inversely correlated with the expression of STAT-3 in BC tissues and cell lines. miR-495 can directly target 3'-UTR of STAT-3 mRNA and thereby decrease the expression of STAT-3 in MCF-7 and HCC1973 cells by Targetscan and Dual-luciferase assay. We further analyzed miR-495 promoter methylation by sodium bisulfite sequencing method (BSP), and found DNA methyltransferase inhibitor, 5-AzaC concomitantly upregulated expression of miR-495 and downregulated its target gene STAT-3 and its downstream target VEGF. Furthermore, we further observed that 5-AzaC treatment, miR-495 mimics and STAT-3 knockdown significantly inhibited cell function in breast cancer by Transwell assay, EdU flow cytometry, Annexin V-FITC/PI combined with flow cytometry and Hoechst staining. Taken together, our data are first to demonstrate that the miR-495 is silenced due to promoter methylation in breast cancer. DNA methyltransferase inhibitor 5-AzaC could reverse miR­495 (suppressor gene) and STAT-3 (oncogene). The anticancer properties of 5-AzaC were preliminarily confirmed in breast cancer.


Assuntos
Neoplasias da Mama/genética , MicroRNAs/genética , Fator de Transcrição STAT3/genética , Fator A de Crescimento do Endotélio Vascular/genética , Apoptose/genética , Azacitidina/administração & dosagem , Neoplasias da Mama/patologia , Movimento Celular/genética , Proliferação de Células/genética , Metilação de DNA/genética , Desmetilação/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Regiões Promotoras Genéticas
12.
EXCLI J ; 16: 354-362, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28507479

RESUMO

Long non-coding RNAs (lncRNAs) have been found to show important regulatory roles in various human cancers. Lnc-RNA PANDAR is a novel identified lncRNA that was previously reported to show abnormal expression pattern in various cancers. However, little is known of its expression and biological function in thyroid cancer. Here, we used the quantitative real-time PCR (qRT-PCR) to determine the expression of PANDAR in 64 thyroid cancer tissues. We found that expression of PANDAR was up-regulated in thyroid cancer tissues compared with adjacent non-tumor tissues. Functional assays in vitro demonstrated that knockdown of PANDAR could inhibit proliferation, cell cycle progression, induces the apoptosis, inhibit invasion of thyroid cancer cells. Thus, our study provides evidence that PANDAR may function as a potential target for treatment for patients with thyroid cancer.

14.
Immunology ; 152(2): 276-286, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28557002

RESUMO

The mammalian target of rapamycin (mTOR) is a serine-threonine kinase that has been shown to be essential for the differentiation and function of various immune cells. Earlier in vitro studies showed that mTOR signalling regulates B-cell biology by supporting their activation and proliferation. However, how mTOR signalling temporally regulates in vivo germinal centre B (GCB) cell development and differentiation into short-lived plasma cells, long-lived plasma cells and memory cells is still not well understood. In this study, we used a combined conditional/inducible knock-out system to investigate the temporal regulation of mTOR complex 1 (mTORC1) in the GCB cell response to acute lymphocytic choriomeningitis virus infection by deleting Raptor, a main component of mTORC1, specifically in B cells in pre- and late GC phase. Early Raptor deficiency strongly inhibited GCB cell proliferation and differentiation and plasma cell differentiation. Nevertheless, late GC Raptor deficiency caused only decreases in the size of memory B cells and long-lived plasma cells through poor maintenance of GCB cells, but it did not change their differentiation. Collectively, our data revealed that mTORC1 signalling supports GCB cell responses at both early and late GC phases during viral infection but does not regulate GCB cell differentiation into memory B cells and plasma cells at the late GC stage.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linfócitos B/enzimologia , Centro Germinativo/enzimologia , Coriomeningite Linfocítica/enzimologia , Vírus da Coriomeningite Linfocítica/imunologia , Complexos Multiproteicos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Animais , Linfócitos B/imunologia , Linfócitos B/transplante , Linfócitos B/virologia , Transplante de Medula Óssea , Diferenciação Celular , Proliferação de Células , Modelos Animais de Doenças , Predisposição Genética para Doença , Centro Germinativo/imunologia , Centro Germinativo/virologia , Interações Hospedeiro-Patógeno , Imunidade Humoral , Memória Imunológica , Ativação Linfocitária , Coriomeningite Linfocítica/genética , Coriomeningite Linfocítica/imunologia , Coriomeningite Linfocítica/virologia , Vírus da Coriomeningite Linfocítica/patogenicidade , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos Endogâmicos C57BL , Camundongos Knockout , Complexos Multiproteicos/deficiência , Complexos Multiproteicos/genética , Complexos Multiproteicos/imunologia , Fenótipo , Plasmócitos/enzimologia , Plasmócitos/imunologia , Plasmócitos/virologia , Proteína Regulatória Associada a mTOR , Transdução de Sinais , Serina-Treonina Quinases TOR/deficiência , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/imunologia , Fatores de Tempo , Quimeras de Transplante
15.
J Affect Disord ; 208: 184-190, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27792961

RESUMO

BACKGROUND: Cognitive-coping therapy (CCT), integrating cognitive theory with stress-coping theory, is an efficacious therapy for obsessive-compulsive disorder (OCD). However, the potential brain mediation for the effectiveness remains unclear. We sought to investigate differences of resting-state brain function between OCD and healthy controls and if such differences would be changed by a four-week CCT. PATIENTS AND METHODS: Thirty-one OCD patients were recruited and randomized into CCT (n=15) and pharmacotherapy plus CCT (pCCT, n=16) groups, together with 25 age-, gender- and education-matched healthy controls. The Yale-Brown Obsessive Compulsive Scale (Y-BOCS) was scored to evaluate the severity in symptoms. Resting-state functional magnetic resonance imaging was scanned pre- and post-treatment. RESULTS: For patients, Y-BOCS scores were reduced during four-week treatment for CCT and pCCT (P<0.001), but no group difference was observed. No differences in amplitude of low-frequency fluctuation (ALFF) values were found between CCT and pCCT either pre- or post-treatment. Compared to controls, ALFF in OCD patients was higher in the left hippocampus, parahippocampus, and temporal lobes, but lower in the right orbitofrontal cortex, rectus, bilateral calcarine, cuneus, lingual, occipital, left parietal, postcentral, precentral, and parietal (corrected P<0.05). The ALFF in those regions was not significantly correlated to the severity of OCD symptoms. After a 4-week treatment, the ALFF differences between OCD patients and controls disappeared. LIMITATIONS: The pharmacotherapy group was not included since OCD patients generally do not respond to pharmacotherapy in four weeks. CONCLUSIONS: Our data indicated that resting-state brain function was different between OCD and controls; such differences disappeared after OCD symptoms were relieved.


Assuntos
Adaptação Psicológica , Encéfalo/fisiopatologia , Terapia Cognitivo-Comportamental , Transtorno Obsessivo-Compulsivo/fisiopatologia , Transtorno Obsessivo-Compulsivo/terapia , Adulto , Terapia Combinada , Feminino , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Masculino , Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Adulto Jovem
16.
Nat Plants ; 2: 16140, 2016 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-27618685

RESUMO

Plants, algae and cyanobacteria need to regulate photosynthetic light harvesting in response to the constantly changing light environment. Rapid adjustments are required to maintain fitness because of a trade-off between efficient solar energy conversion and photoprotection. The xanthophyll cycle, in which the carotenoid pigment violaxanthin is reversibly converted into zeaxanthin, is ubiquitous among green algae and plants and is necessary for the regulation of light harvesting, protection from oxidative stress and adaptation to different light conditions(1,2). Violaxanthin de-epoxidase (VDE) is the key enzyme responsible for zeaxanthin synthesis from violaxanthin under excess light. Here we show that the Chlorophycean VDE (CVDE) gene from the model green alga Chlamydomonas reinhardtii encodes an atypical VDE. This protein is not homologous to the VDE found in plants and is instead related to a lycopene cyclase from photosynthetic bacteria(3). Unlike the plant-type VDE that is located in the thylakoid lumen, the Chlamydomonas CVDE protein is located on the stromal side of the thylakoid membrane. Phylogenetic analysis suggests that CVDE evolved from an ancient de-epoxidase that was present in the common ancestor of green algae and plants, providing evidence of unexpected diversity in photoprotection in the green lineage.


Assuntos
Proteínas de Bactérias/genética , Chlamydomonas reinhardtii/fisiologia , Evolução Molecular , Oxirredutases/genética , Fotossíntese , Proteínas de Bactérias/metabolismo , Chlamydomonas reinhardtii/enzimologia , Chlamydomonas reinhardtii/genética , Oxirredutases/metabolismo , Filogenia , Tilacoides/metabolismo
17.
Oxid Med Cell Longev ; 2016: 4715651, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27594971

RESUMO

Hydrogen sulfide (H2S) has been identified as an important gaseous signal in plants. Here, we investigated the mechanism of H2S in alleviating postharvest senescence and rotting of Kyoho grape. Exogenous application of H2S released from 1.0 mM NaHS remarkably decreased the rotting and threshing rate of grape berries. H2S application also prevented the weight loss in grape clusters and inhibited the decreases in firmness, soluble solids, and titratable acidity in grape pulp during postharvest storage. The data of chlorophyll and carotenoid content suggested the role of H2S in preventing chlorophyll breakdown and carotenoid accumulation in both grape rachis and pulp. In comparison to water control, exogenous H2S application maintained significantly higher levels of ascorbic acid and flavonoid and total phenolics and reducing sugar and soluble protein in grape pulp. Meanwhile, H2S significantly reduced the accumulation of malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide anion (O2 (∙-)) in grape pulp. Further investigations showed that H2S enhanced the activities of antioxidant enzymes ascorbate peroxidase (APX) and catalase (CAT) and decreased those of lipoxygenase (LOX) in both grape peels and pulp. In all, we provided strong evidence that H2S effectively alleviated postharvest senescence and rotting of Kyoho grape by modulating antioxidant enzymes and attenuating lipid peroxidation.


Assuntos
Antioxidantes/metabolismo , Senescência Celular/efeitos dos fármacos , Frutas/efeitos dos fármacos , Sulfeto de Hidrogênio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Sulfetos/farmacologia , Vitis/efeitos dos fármacos , Ascorbato Peroxidases/metabolismo , Ácido Ascórbico/metabolismo , Carotenoides/metabolismo , Catalase/metabolismo , Clorofila/metabolismo , Produtos Agrícolas , Flavonoides/metabolismo , Frutas/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lipoxigenase/metabolismo , Malondialdeído/metabolismo , Fenóis/metabolismo , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo , Vitis/metabolismo
18.
PLoS One ; 11(3): e0151964, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27011211

RESUMO

Clostridium difficile is a spore-forming, gram-positive, anaerobic bacillus that can cause C. difficile infection (CDI). However, only a few studies on the prevalence and antibiotic resistance of C. difficile in healthy individuals in China have been reported. We employed a spore enrichment culture to screen for C. difficile in the stool samples of 3699 healthy Chinese individuals who were divided into 4 groups: infants younger than 2 years of age and living at home with their parents; children aged 1 to 8 years of age and attending three different kindergarten schools; community-dwelling healthy adult aged 23-60 years old; and healthcare workers aged 28-80 years old. The C. difficile isolates were analyzed for the presence of toxin genes and typed by PCR ribotyping and multilocus sequence typing (MLST). The minimum inhibitory concentration of 8 antimicrobial agents was determined for all of the isolates using the agar dilution method. The intestinal carriage rate in the healthy children was 13.6% and ranged from 0% to 21% depending on age. The carriage rates in the 1654 community-dwelling healthy adults and 348 healthcare workers were 5.5% and 6.3%, respectively. Among the isolates, 226 were toxigenic (225 tcdA+/tcdB+ and 1 tcdA+/tcdB+ ctdA+/ctdB+). Twenty-four ribotypes were found, with the dominant type accounting for 29.7% of the isolates. The toxigenic isolates were typed into 27 MLST genotypes. All of the strains were susceptible to vancomycin, metronidazole, fidaxomicin, and rifaximin. High resistance to levofloxacin and ciprofloxacin at rates of 39.8% and 98.3%, respectively, were observed. ST37 isolates were more resistant to levofloxacin than the other STs. The PCR ribotypes and sequence types from the healthy populations were similar to those from the adult patients.


Assuntos
Antibacterianos/farmacologia , Clostridium difficile/efeitos dos fármacos , Clostridium difficile/isolamento & purificação , Farmacorresistência Bacteriana , Enterocolite Pseudomembranosa/tratamento farmacológico , Enterocolite Pseudomembranosa/microbiologia , Intestinos/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , China/epidemiologia , Clostridium difficile/genética , Enterocolite Pseudomembranosa/epidemiologia , Feminino , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Prevalência , Ribotipagem , Adulto Jovem
19.
Biochem Biophys Res Commun ; 471(4): 391-5, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26891869

RESUMO

Metabolic syndrome, which is extremely common in developed and some developing countries, is a clustering of at least three of five of the following medical conditions: abdominal obesity, elevated blood pressure, elevated fasting plasma glucose, high serum triglycerides, and low high-density lipoprotein levels. It has been proved that there is a strong association between metabolic syndrome and breast cancer. Metabolic syndrome could increase the risk of breast cancer and influence the prognosis of the breast cancer patients. Some characteristic of metabolic syndrome such as obesity and lack of physical exercise are all risk factors for developing breast cancer. The metabolic syndrome mainly include obesity, type 2 diabetes, hypercholesterolemia and nonalcoholic fatty liver disease, and each of them impacts the risk of breast cancer and the prognosis of the breast cancer patients in different ways. In this Review, we focus on recently uncovered aspects of the immunological and molecular mechanisms that are responsible for the development of this highly prevalent and serious disease. These studies bring new insight into the complex associations between metabolic syndrome and breast cancer and have led to the development of novel therapeutic strategies that might enable a personalized approach in the management of this disease.


Assuntos
Neoplasias da Mama/etiologia , Síndrome Metabólica/complicações , Síndrome Metabólica/metabolismo , Neoplasias da Mama/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Dislipidemias/complicações , Dislipidemias/metabolismo , Feminino , Humanos , Hiperglicemia/complicações , Hiperglicemia/metabolismo , Resistência à Insulina/fisiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Fatores de Risco
20.
Psychiatry Res ; 229(3): 732-8, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26275705

RESUMO

Pharmacotherapy and cognitive-behavioral therapy (CBT) present limitations when they are used to treat obsessive-compulsive disorder (OCD), a severe and debilitating psychiatric disorder. To search for more efficacious treatment, we investigated the effects of pharmacotherapy plus cognitive-coping therapy (pCCT) on adult OCD patients with overt or covert compulsions. Two hundred and fifteen OCD patients were randomized into pharmacotherapy plus psychological support (PPS, n=107) and pCCT (n=108). The Yale-Brown Obsessive Compulsive Scale (Y-BOCS) was used to measure severity of symptoms in the OCD patients. The Y-BOCS scores were significantly lower in pCCT than in PPS in both acute term (<3 months) and long-term follow-up. In pCCT, severity of symptoms was not different between those with covert compulsions and those with overt compulsions, but was significantly reduced at any post-treatment time-point. Y-BOCS scores in the two subtype compulsions were significantly lower in pCCT than in PPS at any post-treatpost-treatment time-point. Compared with PPS, effect size, response rate and remission rate were significantly higher in pCCT. Our findings corroborated with the hypothesis that pCCT could efficaciously treat OCD with overt compulsions or covert compulsion, suggesting that pCCT might be a potential option for adult OCD.


Assuntos
Adaptação Psicológica , Terapia Cognitivo-Comportamental/métodos , Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Transtorno Obsessivo-Compulsivo/reabilitação , Adulto , Clomipramina/uso terapêutico , Cognição , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Transtorno Obsessivo-Compulsivo/psicologia , Escalas de Graduação Psiquiátrica , Inibidores de Captação de Serotonina , Índice de Gravidade de Doença , Resultado do Tratamento
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