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1.
Food Chem X ; 20: 100940, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38144809

RESUMO

Red Monascus pigments (MPs) are a large group of polyketides from the fungus Monascus which have been widely used as food colorants. In this study, a variety of red MPs congeners were prepared to explore promising water-soluble candidates for application in liquid food formulations. The results showed that by combining the two-stage, low-pH fermentation strategy with a downstream purification step of fractional crystallization, precursors of red MPs, namely monascorubrin and rubropunctatin, were obtained with a purity of 91.9%. Then, via the azaphilic addition reaction, 18 types of red MPs congeners carrying different amino acid moieties (MPs-aa) were semi-synthesized. Compared to rubropunctamine and monascorubramine, the water solubility, pH and thermal stability of MPs-aa were improved greatly. MPs-His, MPs-Phe, MPs-Tyr and MPs-Trp were identified to be the most resistant to pasteurization. These findings provide water-soluble red MPs candidates with high thermal stability and an attractive approach for their large scale production.

2.
Molecules ; 28(14)2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37513263

RESUMO

Tremella sanguinea is a traditional Chinese medicinal and edible mushroom. Polysaccharides from Tremella mushrooms have received increasing amounts of research attention due to their diverse pharmacological activities. In this study, via the incubation of basidiospores collected from fresh artificially cultivated basidiocarps of T. sanguinea, a haploid yeast strain of T. sanguinea was obtained, and it was found to be a typical loose-slime-forming yeast capable of producing a large amount of exopolysaccharides (EPS). Using DEAE-52 cellulose column chromatography and Sephadex G-100 gel permeation chromatography, the major polysaccharide, named TSPS-1, was separated and purified from the EPS produced by the haploid yeast strain of T. sanguinea. TSPS-1 was a homogeneous polysaccharide with a molecular weight of 2.5 × 103 kDa and consisted of rhamnose, glucose, xylose, mannose and glucuronic acid at a molar ratio of 1: 0.7: 62.2: 24.6: 11.5. The bioactivity of the TSPS-1 polysaccharide was evaluated. The results show that TSPS-1 exhibited noticeable antioxidant activity by scavenging hydroxyl radicals (EC50 = 1.92 mg/mL) and superoxide radicals (EC50 = 1.33 mg/mL), and prebiotic activity by promoting the growth of different probiotic strains in the genus Lactobacillus and Bifidobacterium. These results suggest that the cultivation of the haploid yeast strain can be a promising alternative for the efficient production of valuable T. sanguinea polysaccharides with antioxidant and prebiotic potential.


Assuntos
Agaricales , Antioxidantes , Antioxidantes/química , Saccharomyces cerevisiae , Haploidia , Polissacarídeos/química
3.
Int Immunopharmacol ; 108: 108864, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35623293

RESUMO

Osteoarthritis has become the fourth cause of disability in the world and its occurrence and development are caused by apoptosis and extracellular matrix (ECM) degradation of chondrocytes. Asiaticoside (ASI) is a triterpene saponin compound obtained from Centella Asiatica and has anti-inflammatory and anti-apoptotic effects in various diseases. However, its effects on OA are not clear. In this study, we reported that ASI has a protective effect on the occurrence and progression of OA in vivo and in vitro, and demonstrated its potential molecular mechanism. In vitro, ASI treatment inhibited the release of pro-apoptotic factors induced by TBHP and promoted the release of the anti-apoptotic proteins. In addition, ASI promotes the expression of Aggrecan and Collagen II, while inhibiting the expression of thrombospondin motifs 5 (ADAMTS5) and matrix metalloproteinase-13 (MMP-13), which causes extracellular matrix (ECM) degradation. Mechanistically, ASI exerts its anti-apoptotic effect by activating the Nrf2/HO-1 pathway and preventing p65 from binding to DNA. Similarly, in vivo, ASI has been shown to have a protective effect in a mouse OA model. The conclusion is that our research shows that ASI can be used as a potential drug for the treatment of OA.


Assuntos
Osteoartrite , Triterpenos , Animais , Camundongos , Condrócitos , Modelos Animais de Doenças , Heme Oxigenase-1/metabolismo , Interleucina-1beta/metabolismo , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Osteoartrite/metabolismo , Triterpenos/farmacologia , Triterpenos/uso terapêutico
4.
Food Microbiol ; 102: 103901, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34809933

RESUMO

Clostridium perfringens (C. perfringens) is a zoonotic microorganism and rarely reported in duck production chain. This study aimed to investigate prevalence, serotype distribution, antibiotic resistance and genetic diversity of C. perfringens at different stages of a duck production chain. In total, 319 samples were collected from a large-scale rearing and slaughter one-stop enterprise in Weifang, China, of which 42.95% of samples were positive for C. perfringens. All isolates were genotype A. Cpe and cpb2 genes were found in 2.54% and 24.87% of the isolates, respectively. Antimicrobial susceptibility testing revealed that 55.47% of the isolates resistant to at least 5 classes of commonly used antibiotics. Multilocus sequence typing (MLST) results showed that 65 representative isolates were divided into 47 sequences types (STs), 33.85% of them were included into four clonal complexes (CC). Some of isolates from breeding and slaughtering stages were distributed in the same CC or ST, indicating duck products may be contaminated by C. perfringens originated from the breeding stage. Part of duck isolates were distributed in the same CC as human isolates and systemically close with human isolates. The high contamination rates of duck products, the isolates with multi-drug antibiotic resistance or the cpe gene, and the close relationship between strains from human and ducks, indicated potential public health risks, not only control measures at slaughtering stage but also at rearing stage should be considered to reduce this risks.


Assuntos
Infecções por Clostridium , Clostridium perfringens , Patos/microbiologia , Aves Domésticas , Animais , Antibacterianos/farmacologia , China , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/veterinária , Clostridium perfringens/classificação , Clostridium perfringens/isolamento & purificação , Farmacorresistência Bacteriana , Tipagem de Sequências Multilocus , Aves Domésticas/microbiologia , Prevalência
5.
Food Sci Biotechnol ; 30(4): 545-553, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33936846

RESUMO

The yellow Monascus pigments (YMPs) named monascin and ankaflavin and the orange Monascus pigments (OMPs) named rubropunctatin and monascorubrin are two groups of bioactive components in a mixture state in the Monascus fermented products. In order to separate these two groups of bioactive pigments, a facile macroporous resin-based method was developed. The weak-polar resin CAD-40 was selected from the seven tested macroporous resins as it revealed better properties for the adsorption and desorption of the YMPs and OMPs. Then, CAD-40 resin was used for column-chromatographic separation. After eluted by 4 bed volumes of ethanol, the yellow group (monascin and ankaflavin) and the orange group (rubropunctatin and monascorubrin) were successfully separated and purified, with an increased content from 49.3% and 44.2% in the crude pigment extract to 85.2% and 83.0% in the final products, respectively. This method would be helpful for the large-scale separation and purification of Monascus pigment products with specific bioactivity.

6.
Nat Commun ; 12(1): 2131, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837201

RESUMO

Controlling the reactivity of reactive intermediates is essential to achieve selective transformations. Due to the facile 1,5-hydrogen atom transfer (HAT), alkoxyl radicals have been proven to be important synthetic intermediates for the δ-functionalization of alcohols. Herein, we disclose a strategy to inhibit 1,5-HAT by introducing a silyl group into the α-position of alkoxyl radicals. The efficient radical 1,2-silyl transfer (SiT) allows us to make various α-functionalized products from alcohol substrates. Compared with the direct generation of α-carbon radicals from oxidation of α-C-H bond of alcohols, the 1,2-SiT strategy distinguishes itself by the generation of alkoxyl radicals, the tolerance of many functional groups, such as intramolecular hydroxyl groups and C-H bonds next to oxygen atoms, and the use of silyl alcohols as limiting reagents.

7.
Zoonoses Public Health ; 68(5): 431-442, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33878232

RESUMO

The current study is undertaken to characterize the prevalence, genotypes distribution, antibiotic resistance and genetic diversity of Clostridium perfringens (C. perfringens) collected from different stages of a chicken production chain. In total, 579 samples from a broiler farm and 378 samples from the slaughterhouse were collected from a large-scale rearing and slaughter one-stop enterprise in Weifang, China, between June and July 2019, of which 30.40% of the samples from farm and 54.50% of samples from slaughterhouse were determined to be positive for C. perfringens, respectively. The contamination of chicken products was relatively serious, with the total positive rate of carcasses at 59.73%; the positive rate of carcass samples was the highest in the evisceration process, which might be the critical point of C. perfringens contamination. A total of 476 isolates of C. perfringens were recovered; and 99.58% of recovered isolates were identified as type A, with the remaining isolates being type G. Antimicrobial susceptibility testing revealed that 97.15% of the isolates showed multiple antibiotic resistance and 67.89% of them were resistant to at least five classes of commonly used antibiotics. Multilocus sequence typing results of 91 representative isolates showed that the isolates can be divided into 74 sequences types (STs); 40.66% of the isolates can be included into seven clonal complexes (CCs). Although most of the isolates were classified as type A, considerable genetic diversity was observed, with the Simpson's diversity index of ST up to 0.9902. Some isolates from farm stage and slaughter stage were distributed in the same ST or CC, indicating that chicken products may be contaminated by the same ST or CC of C. perfringens originated from the farm stage. The high contamination rates of chicken products and the widespread multiple antibiotic resistance of isolates indicated potential public health risks, control measures at rearing and slaughtering stage should be considered to reduce this risk.


Assuntos
Galinhas/microbiologia , Infecções por Clostridium/veterinária , Clostridium perfringens , Tipagem de Sequências Multilocus/veterinária , Doenças das Aves Domésticas/microbiologia , Matadouros , Animais , Infecções por Clostridium/microbiologia , Clostridium perfringens/classificação , Fazendas , Zoonoses
8.
Org Biomol Chem ; 18(40): 8192-8198, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33030197

RESUMO

Stereoselectively-fluorinated analogs of pipecolic acid have been investigated through a combined theoretical and experimental approach. Three of the four possible diastereoisomers of 4,5-difluoropipecolic acid were successfully synthesized via deoxyfluorination chemistry, navigating a complex reaction network that included neighboring group participation, rearrangement, and elimination pathways. A DFT-based conformational study, supported by NMR J-based analysis, revealed that the different diastereoisomers of 4,5-difluoropipecolic acid preferentially adopt different puckers of the six-membered ring. These findings could have future relevance for the conformational control of biologically active peptides.


Assuntos
Ácidos Pipecólicos
9.
Infect Dis Poverty ; 9(1): 143, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33076968

RESUMO

BACKGROUND: Effective management of imported cases is an important part of epidemic prevention and control. Hainan Province, China reported 168 coronavirus disease 2019 (COVID-19), including 112 imported cases on February 19, 2020, but successfully contained the epidemic within 1 month. We described the epidemiological and clinical characteristics of COVID-19 in Hainan and compared these features between imported and local cases to provide information for other international epidemic areas. METHODS: We included 91 patients (56 imported and 35 local cases) from two designated hospitals for COVID-19 in Haikou, China, from January 20 to February 19, 2020. Data on the demographic, epidemiological, clinical and laboratory characteristics were extracted from medical records. Patients were followed until April 21, 2020, and the levels of antibodies at the follow-ups were also analysed by the Wilcoxon matched-pairs signed ranks test. RESULTS: Of the 91 patients, 78 (85.7%) patients were diagnosed within the first three weeks after the first case was identified (Day 1: Jan 22, 2020), while the number of local cases started to increase during the third week. No new cases occurred after Day 29. Fever and cough were two main clinical manifestations. In total, 15 (16.5%) patients were severe, 14 (15.4%) had complicated infections, nine (9.9%) were admitted to the intensive care unit, and three died. The median duration of viral shedding in feces was longer than that in nasopharyngeal swabs (19 days vs 16 days, P = 0.007). Compared with local cases, imported cases were older and had a higher incidence of fever and concurrent infections. There was no difference in outcomes between the two groups. IgG was positive in 92.8% patients (77/83) in the follow-up at week 2 after discharge, while 88.4% patients (38/43) had a reduction in IgG levels in the follow-up at week 4 after discharge, and the median level was lower than that in the follow-up at week 2 (10.95 S/Cut Off (S/CO) vs 15.02 S/CO, P <  0.001). CONCLUSION: Imported cases were more severe than local cases but had similar prognoses. The level of IgG antibodies declined from week 6 to week 8 after onset. The short epidemic period in Hainan suggests that the epidemic could be quickly brought under control if proper timely measures were taken.


Assuntos
Doenças Transmissíveis Importadas/epidemiologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Adulto , Idoso , Betacoronavirus/isolamento & purificação , COVID-19 , China/epidemiologia , Doenças Transmissíveis Importadas/diagnóstico , Doenças Transmissíveis Importadas/terapia , Doenças Transmissíveis Importadas/virologia , Infecções por Coronavirus/virologia , Fezes/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/virologia , Estudos Retrospectivos , SARS-CoV-2 , Tórax/diagnóstico por imagem , Resultado do Tratamento , Eliminação de Partículas Virais
10.
Poult Sci ; 99(10): 5105-5117, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988549

RESUMO

Clostridium perfringens is an important zoonotic microorganism. The present study was undertaken to investigate prevalence, serotype distribution, antibiotic resistance, and genetic diversity of C. perfringens isolates from 4 duck farms in Shandong, China. In total, 424 samples of cloacal swabs and environment were collected from 3 commercial meat-type duck farms in Tai'an, Liaocheng, and Weifang and one breeder duck farm in Liaocheng between December 2018 and June 2019, of which, 207 (48.82%) samples were determined to be positive for C. perfringens; a total of 402 isolates of C. perfringens were recovered, all of which were identified as type A; 30.85% of the isolates were positive for cpb2 gene; and cpe gene was found in 0.5% of the isolates. Antimicrobial susceptibility testing revealed that some of the isolates exhibited high antibiotic resistance, and 39.14% of the isolates were resistant to at least 5 classes of commonly used antibiotics. Multilocus sequence typing analysis showed that 85 representative isolates encompassed 54 different sequences types (STs), clustered in 5 clonal complexes (CCs) and 40 singletons. ST3, the most common ST in 54 STs, constituting 15.29% of all isolates, was also the most prevalent ST of isolates from the Liaocheng breeder duck farm (farm 3). CC1, the most prolific CC, containing 15.29% of the analyzed isolates, was the popular subtype of isolates from Liaocheng meat duck farm (farm 2). Although all the isolates belong to type A, the genetic diversity varied greatly in different regions; the Simpson's Diversity Index of STs for Liaocheng, Tai'an, and Weifang were 0.5941, 0.9198, and 0.9627, respectively. Some of cloacal isolates and environmental isolates were distributed in the same ST or CC, indicating close genetic relationship between cloacal isolates and environmental isolates. A portion of the strains from humans and ducks was found to be phylogenetically close. The close relationship between strains from humans and ducks, the high antibiotic resistance of C. perfringens, and the cpe-positive isolates indicated potential public health risks.


Assuntos
Infecções por Clostridium , Clostridium perfringens , Patos , Animais , Antibacterianos/farmacologia , China/epidemiologia , Infecções por Clostridium/microbiologia , Infecções por Clostridium/veterinária , Clostridium perfringens/efeitos dos fármacos , Clostridium perfringens/genética , Clostridium perfringens/isolamento & purificação , Fazendas , Tipagem de Sequências Multilocus/veterinária , Prevalência
11.
Int J Biol Macromol ; 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32339571

RESUMO

Molecular tools of double or multimeric G-quadruplexes have been given higher requirements on detection sensitivity, thermal stabilization and cell imaging to establish functions of these G-quadruplex aggregates and biological mechanisms as anticancer reagents. Here, two smart berberine-bisquinolinium conjugates (Ber-360A and Ber-PDS) by linking the berberine fluorophore ligand and an established G-quadruplex binder (i.e. bisquinolinium scaffold), have been designed and evaluated their activities and mechanisms for G-quadruplex aggregation. Two conjugates, especially Ber-PDS, are two highly selective, sensitive and fluorescent sensors which can distinguish human telomere double G-quadruplexes from other type G-quadruplexes and ds DNA. These two ligands could be the first example to stack two adjacent G-quadruplex units and fluorescently recognize human telomere double G-quadruplexes. Furthermore, conjugate Ber-PDS could enter the nucleoli and target G-quadruplex DNA through microscopy experiments, and also display strong telomerase inhibition and antitumor activities.

12.
Org Biomol Chem ; 17(45): 9799-9807, 2019 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-31709436

RESUMO

We have realized the first Ullmann type coupling reaction of tri(di)fluoroethylamine with (hetero)aromatic bromides, employing 5-20 mol% Cu2O and an oxalamide ligand [N-(2,4,6-trimethoxyphenyl)acetamide]. This efficient and practical method has the following features: (i) avoids the use of an expensive catalyst; (ii) does not require anhydrous solvent and strict air extrusion; (iii) uses bench stable and inexpensive (hetero)aromatic bromides; (iv) is suitable for the synthesis of fluoroalkylated hetero-aromatic substrates; (v) is suitable for gram-scale synthesis. This work also shows the "negative fluorine effect" for the alkylamines in the copper catalysed coupling reactions.

13.
Appl Microbiol Biotechnol ; 103(20): 8393-8402, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31501941

RESUMO

The influence of pH on the biosynthesis of orange Monascus pigments (OMPs) in Monascus ruber M7 was investigated. Under acidic fermentation conditions, pigment mixtures predominantly rich in OMPs were obtained. HPLC analysis revealed the presence of four orange components (O1-O4) and four yellow components (Y1-Y4) in the mixtures, and the dominant ones were O1 and O3, which accounted for 56.0% to 75.9% of the total pigments in the pH range 3-6. Subsequently, O1 and O3 were identified by LC-DAD-ESI/MS as Rubropunctatin and Monascorubrin, respectively. The yield of OMPs was observed to be inversely dependent on pH. At pH 3, large amounts of OMPs with high purity (79.1%) were accumulated. A real-time quantitative PCR analysis revealed that the expression of genes related to the biosynthesis of OMPs in M. ruber M7 was upregulated at acidic pH as compared to neutral pH, and the variation in the level of expression of these genes with pH was consistent with the production of OMPs. These results indicated that the large accumulation of OMPs under acidic condition involved the acidic pH-induced transcription of genes related to the biosynthesis of OMPs. These results would contribute towards the development of an efficient technology for large-scale production of OMPs.


Assuntos
Meios de Cultura/química , Monascus/crescimento & desenvolvimento , Monascus/metabolismo , Pigmentos Biológicos/metabolismo , Cromatografia Líquida , Fermentação , Concentração de Íons de Hidrogênio , Pigmentos Biológicos/química , Pigmentos Biológicos/classificação , Espectrometria de Massas por Ionização por Electrospray
14.
Org Lett ; 20(3): 860-863, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29360383

RESUMO

A one-pot protocol for the construction of fluoroalkylated isoxazoles directly from commercially available amines and alkynes is described. The reaction is scalable, operationally simple, regioselective, mild, and tolerant of a broad range of functional groups. As such, it could be viewed as a "click synthesis" of fluoroalkylated isoxazoles. Preliminary mechanistic investigations reveal that the transformation involves an unprecedented Cu-catalyzed cascade sequence involving RfCHN2.

15.
Oncol Res Treat ; 38(10): 503-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26451891

RESUMO

BACKGROUND: Gastric cardia adenocarcinoma (GCA) is a common malignant tumor of the digestive tract with a high incidence in China. Genetic factors such as single nucleotide polymorphisms (SNPs) may contribute to the carcinogenesis of GCA. METHODS: We conducted a hospital-based case-control study to evaluate the genetic association of functional SNPs with susceptibility to GCA development. A total of 330 GCA cases and 608 controls were recruited for this study. The SNPs OPG rs3102735 T>C and rs2073618 G>C, RANK rs1805034 T>C, and RANKL rs9533156 T>C and rs2277438 A>G were determined using the ligation detection reaction method. RESULTS: Our findings suggest that RANK rs1805034 T>C is associated with susceptibility to GCA, which is more evident among male patients, elderly patients (≥ 60 years), smokers, and patients who do not consume alcohol. CONCLUSION: Based on our findings, the functional SNP RANK rs1805034 T>C may be an indicator for individual susceptibility to GCA. However, further larger studies with other ethnic populations and tissue-specific biological characterization are required to confirm the current findings.


Assuntos
Adenocarcinoma/epidemiologia , Adenocarcinoma/genética , Receptor Ativador de Fator Nuclear kappa-B/genética , Fumar/epidemiologia , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/genética , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Feminino , Marcadores Genéticos/genética , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Distribuição por Sexo
16.
J Virol ; 89(14): 7028-37, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25926657

RESUMO

UNLABELLED: Enterovirus 71 (EV71) infection causes severe mortality involving multiple possible mechanisms, including cytokine storm, brain stem encephalitis, and fulminant pulmonary edema. Gamma interferon (IFN-γ) may confer anti-EV71 activity; however, the claim that disease severity is highly correlated to an increase in IFN-γ is controversial and would indicate an immune escape initiated by EV71. This study, investigating the role of IFN-γ in EV71 infection using a murine model, showed that IFN-γ was elevated. Moreover, IFN-γ receptor-deficient mice showed higher mortality rates and more severe disease progression with slower viral clearance than wild-type mice. In vitro results showed that IFN-γ pretreatment reduced EV71 yield, whereas EV71 infection caused IFN-γ resistance with attenuated IFN-γ signaling in IFN regulatory factor 1 (IRF1) gene transactivation. To study the immunoediting ability of EV71 proteins in IFN-γ signaling, 11 viral proteins were stably expressed in cells without cytotoxicity; however, viral proteins 2A and 3D blocked IFN-γ-induced IRF1 transactivation following a loss of signal transducer and activator of transcription 1 (STAT1) nuclear translocation. Viral 3D attenuated IFN-γ signaling accompanied by a STAT1 decrease without interfering with IFN-γ receptor expression. Restoration of STAT1 or blocking 3D activity was able to rescue IFN-γ signaling. Interestingly, viral 2A attenuated IFN-γ signaling using another mechanism by reducing the serine phosphorylation of STAT1 following the inactivation of extracellular signal-regulated kinase without affecting STAT1 expression. These results demonstrate the anti-EV71 ability of IFN-γ and the immunoediting ability by EV71 2A and 3D, which attenuate IFN-γ signaling through different mechanisms. IMPORTANCE: Immunosurveillance by gamma interferon (IFN-γ) may confer anti-enterovirus 71 (anti-EV71) activity; however, the claim that disease severity is highly correlated to an increase in IFN-γ is controversial and would indicate an immune escape initiated by EV71. IFN-γ receptor-deficient mice showed higher mortality and more severe disease progression, indicating the anti-EV71 property of IFN-γ. However, EV71 infection caused cellular insusceptibility in response to IFN-γ stimulation. We used an in vitro system with viral protein expression to explore the novel IFN-γ inhibitory properties of the EV71 2A and 3D proteins through the different mechanisms. According to this study, targeting either 2A or 3D pharmacologically and/or genetically may sustain a cellular susceptibility in response to IFN-γ, particularly for IFN-γ-mediated anti-EV71 activity.


Assuntos
Enterovirus Humano A/imunologia , Infecções por Enterovirus/imunologia , Interações Hospedeiro-Patógeno , Interferon gama/antagonistas & inibidores , Transdução de Sinais , Proteínas Virais/metabolismo , Animais , Linhagem Celular , Modelos Animais de Doenças , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout
17.
Water Res ; 52: 242-50, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24275106

RESUMO

Anaerobic digestion is promising technology to recover energy from waste activated sludge. However, the sludge digestion is limited by its low efficiency of hydrolysis-acidification. Zero valent iron (ZVI) as a reducing material is expected to enhance anaerobic process including the hydrolysis-acidification process. Considering that, ZVI was added into an anaerobic sludge digestion system to accelerate the sludge digestion in this study. The results indicated that ZVI effectively enhanced the decomposition of protein and cellulose, the two main components of the sludge. Compared to the control test without ZVI, the degradation of protein increased 21.9% and the volatile fatty acids production increased 37.3% with adding ZVI. More acetate and less propionate are found during the hydrolysis-acidification with ZVI. The activities of several key enzymes in the hydrolysis and acidification increased 0.6-1 time. ZVI made the methane production raise 43.5% and sludge reduction ratio increase 12.2 percent points. Fluorescence in situ hybridization analysis showed that the abundances of hydrogen-consuming microorganisms including homoacetogens and hydrogenotrophic methanogens with ZVI were higher than the control, which reduced the H2 accumulation to create a beneficial condition for the sludge digestion in thermodynamics.


Assuntos
Ferro , Esgotos , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Biocombustíveis , Enzimas/metabolismo , Ácidos Graxos/metabolismo , Hidrogênio/metabolismo , Hidrólise , Hibridização in Situ Fluorescente , Metano/metabolismo , Consórcios Microbianos , Polissacarídeos/metabolismo , Proteínas/metabolismo , Esgotos/microbiologia
18.
Asian Pac J Cancer Prev ; 14(7): 4301-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23991993

RESUMO

AIM: Apoptosis has been considered as a fundamental component in cancer pathogenesis, and related genetic factors might play an important role in gastric cardiac adenocarcinoma (GCA) genesis. METHODS: We conducted a hospital based case-control study to evaluate the genetic effects of functional single nucleotide polymorphisms (SNPs): BCL2 rs17757541 C>G, BCL2 rs12454712 T>C, FAS rs2234767 G>A, FASL/FASLG rs763110 C>T, ERBB2 rs1136201 A>G and VEGFR2/KDR rs11941492 C>T on the development of GCA. A total of 243 GCA cases and 476 controls were recruited for the study and genotypes were determined using a custom-by-design 48-Plex SNPscanTM Kit. RESULTS: The BCL2 rs17757541 C>G polymorphism was associated with increased risk of GCA. However, there was no significant associations with the other five SNPs. Stratified analyses indicated a significantly increased risk of GCA associated with the BCL2 rs17757541 C>G polymorphism among males, older patients and those with a history of smoking or drinking. CONCLUSION: These findings indicated that the functional polymorphism BCL2 rs17757541 C>G might contribute to GCA susceptibility. However, our results were limited by small sample size. Future larger studies are required to confirm our current findings.


Assuntos
Adenocarcinoma/etiologia , Biomarcadores Tumorais/genética , Cárdia/patologia , Polimorfismo de Nucleotídeo Único/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Neoplasias Gástricas/etiologia , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Idoso , Estudos de Casos e Controles , China/epidemiologia , Feminino , Seguimentos , Genótipo , Humanos , Masculino , Estadiamento de Neoplasias , Prognóstico , Fatores de Risco , Fumar , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/patologia
19.
Immunobiology ; 217(9): 926-34, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22325465

RESUMO

Oncogenic activation accompanied by escape from immune surveillance, such as IFN-γ resistance, is critical for cancer cell growth and survival. In this study, we investigated the crosstalk signaling between IFN-γ resistance and signaling of hyperproliferation in gastric cancer cells. IFN-γ inhibited the cell growth of MKN45 cells but not hyperproliferating AGS cells. AGS cells did not respond to IFN-γ because of a decrease in STAT1 but not due to dysfunctional IFN-γ receptors. Signaling of PI3K/AKT, as well as MEK/ERK, was required for the hyperproliferation; notably, PI3K/AKT alone mediated the IFN-γ resistance. Aberrant Src homology-2 domain-containing phosphatase (SHP) 2 determined IFN-γ resistance but unexpectedly had no effects on hyperproliferation or ERK activation. In the IFN-γ resistant cells, inactivation of glycogen synthase kinase (GSK)-3ß by PI3K/AKT was important for SHP2 activation but not for hyperproliferation. An imbalance of AKT/GSK-3ß/SHP2 caused by a reduction of PTEN was important for the crosstalk between IFN-γ resistance and hyperproliferation. PI3K is constitutively expressed in AGS cells and immunohistochemical staining showed a correlation between hyperproliferation and expression of SHP2 and STAT1 in gastric tumors. These results demonstrate the effects of PTEN/AKT/GSK-3ß/SHP2 signaling on IFN-γ resistance in hyperproliferating gastric cancer cells.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Quinase 3 da Glicogênio Sintase/metabolismo , Interferon gama/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática , Glicogênio Sintase Quinase 3 beta , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
Microbes Infect ; 13(11): 888-94, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21664983

RESUMO

Autophagy, that is directly triggered by invaded pathogens and indirectly triggered by IFN-γ, acts as a defense by mediating intracellular microbial recognition and clearance. In addition, autophagy contributes to inflammation by facilitating an IFN-γ response and signal transduction. For immune escape, downregulated autophagy may be a strategy used by microbes.


Assuntos
Autofagia/imunologia , Interferon gama/imunologia , Transdução de Sinais , Doenças Transmissíveis/imunologia , Evasão da Resposta Imune , Inflamação/imunologia
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