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1.
Angew Chem Int Ed Engl ; 63(28): e202406937, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38656692

RESUMO

Polymers are ideally utilized as damping materials due to the high internal friction of molecular chains, enabling effective suppression of vibrations and noises in various fields. Current strategies rely on broadening the glass transition region or introducing additional relaxation components to enhance the energy dissipation capacity of polymeric damping materials. However, it remains a significant challenge to achieve high damping efficiency through structural control while maintaining dynamic characteristics. In this work, we propose a new strategy to develop hyperbranched vitrimers (HBVs) containing dense pendant chains and loose dynamic crosslinked networks. A novel yet weak dynamic transesterification between the carboxyl and boronic acid ester was confirmed and used to prepare HBVs based on poly (hexyl methacrylate-2-(4-ethenylphenyl)-5,5-dimethyl-1,3,2-dioxaborinane) P(HMA-co-ViCL) copolymers. The A B n ${{AB}_{n}}$ -type of macromonomers, the crosslinking points formed by the dynamic covalent connection via the associative exchange, and the weak yet dynamic exchange reaction are the three keys to developing high-performance HBV damping materials. We found that P(HMA-co-ViCL) 20k-40-60 HBV exhibited ultrahigh energy-dissipation performance over a broad frequency and temperature range, attributed to the synergistic effect of dense pendant chains and weak dynamic covalent crosslinks. This unique design concept will provide a general approach to developing advanced damping materials.

2.
Soft Matter ; 19(46): 8965-8977, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37962482

RESUMO

The jamming effect is critical in processing short fiber-reinforced thermoplastics (FRTs). Fiber jamming can induce discontinuous shear thickening (DST) in simple shear and result in fiber-matrix separation in more complex flows such as injection molding and compression molding of FRTs. The confinement effect commonly induces local jams and strongly enhances fiber jamming. However, the transient evolution of local fiber jams under confinement and its correlation with the tumbling of fibers are still elusive. In this study, we adopted rheo-PIV (particle image velocity) techniques to study this effect for glass fiber-reinforced thermoplastics (FRTs). The translational and tumbling motion of fiber were determined during rheological measurements, and the distribution of fiber orientation was determined by X-ray CT. Three shear banding regions appeared after the viscosity overshoot under high shear stress in suspensions with high fiber content, which was associated with the three regions of fiber orientation across the gap due to confinement. Shear banding was ascribed to the different tumbling speeds across the gap because of the different initial orientations and different wall confinements near and far from the wall. The local shear thickening and jamming behavior became most significant under intermediate confinement, and were affected by shear strain, shear stress, and fiber contents. 3D state diagrams were constructed to show the confinement effect on the evolution of shear banding and jamming.

3.
J Pharmacol Sci ; 152(2): 151-161, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37169480

RESUMO

Microglia hyperactivation is an important cause of neuroinflammation in Alzheimer's disease (AD). Paeoniflorin (PF), ferulic acid (FA), and atractylenolide III (ATL) are potent in anti-inflammation and neuroprotection. Multiple components can act on different targets simultaneously to exert synergistic therapeutic effects and exploring the synergistic potential between compounds is an important area of research. We investigated the effects of PF, FA, and ATL, alone or in combination, on LPS-induced neuroinflammation and autophagy in BV2 microglia cells. We found that PF, FA, and ATL, alone or in combination, significantly reduced the production of inflammatory factors such as IL-6, IL-1ß, and TNF-α, especially in the PF + FA + ATL group, which performed the best. In addition, the combination of PF, FA, and ATL significantly increased the expression of autophagy-related proteins p-AMPK, p-ULK1, Beclin1, LC3, and TFEB and decreased the expression of p62. Moreover, the restoration of autophagic flux by the combination of PF, FA, and ATL was abrogated by the addition of the autophagy inhibitor Wortmannin. In conclusion, PF, FA, and ATL have a synergistic effect in reducing LPS-induced inflammatory factor release from BV2 microglia cells, and its protective effect may be through activation of the AMPK/ULK1/TFEB autophagic signaling pathway.


Assuntos
Lipopolissacarídeos , Microglia , Humanos , Microglia/metabolismo , Lipopolissacarídeos/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Doenças Neuroinflamatórias , Autofagia
4.
Molecules ; 28(8)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37110714

RESUMO

In neurodegenerative diseases, microglial activation and neuroinflammation are essential for the control and progression of neurodegenerative diseases. Mitigating microglium-induced inflammation is one strategy for hindering the progression of neurodegenerative diseases. Ferulic acid (FA) is an effective anti-inflammatory agent, but its potential role and regulation mechanism in neuroinflammatory reactions have not been fully studied. In this study, the neuroinflammation model was established by lipopolysaccharide (LPS), and the inhibitory effect of FA on neuroinflammation of BV2 microglia was studied. The results showed that FA significantly reduced the production and expression of reactive oxygen species (ROS), tumor necrosis factor-α (TNF-α), leukocyte-6 (IL-6) and interleukin-1ß (IL-1ß). We further studied the mechanism of FA's regulation of LPS-induced BV2 neuroinflammation and found that FA can significantly reduce the expression of mTOR in BV2 microglia induced by LPS, and significantly increase the expression of AMPK, indicating that FA may have an anti-inflammatory effect by activating the AMPK/mTOR signaling pathway to regulate the release of inflammatory mediators (such as NLRP3, caspase-1 p20 and IL-1ß). We further added an autophagy inhibitor (3-MA) and an AMPK inhibitor (compound C, CC) for reverse verification. The results showed that FA's inhibitory effects on TNF-α, IL-6 and IL-1ß and its regulatory effect on AMPK/mTOR were destroyed by 3-MA and CC, which further indicated that FA's inhibitory effect on neuroinflammation is related to its activation of the AMPK/mTOR autophagy signaling pathway. In a word, our experimental results show that FA can inhibit LPS-induced neuroinflammation of BV2 microglia by activating the AMPK/mTOR signaling pathway, and FA may be a potential drug for treating neuroinflammatory diseases.


Assuntos
Lipopolissacarídeos , Doenças Neurodegenerativas , Humanos , Lipopolissacarídeos/farmacologia , Microglia , Proteínas Quinases Ativadas por AMP/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Doenças Neuroinflamatórias , Transdução de Sinais , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Doenças Neurodegenerativas/metabolismo , NF-kappa B/metabolismo
5.
Medicina (Kaunas) ; 59(1)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36676799

RESUMO

Background and Objectives: Job burnout is prevalent among primary care providers (PCPs) in different countries, and the factors that can alleviate burnout in these countries have been explored. However, no study has addressed the prevalence and the correlates of job burnout among Togolese PCPs. Therefore, we aimed to examine the prevalence of burnout and its association with social support and psychological capital among PCPs in Togo. Material and Methods: We conducted a cross-sectional study in Togo from 5 to 17 November 2020 among 279 PCPs of 28 peripheral care units (PCUs). Participants completed the Maslach Burnout Inventory, Job Content Questionnaire, and Psychological Capital Questionnaire. Data were analyzed using the Mann-Whitney U test, Kruskal-Wallis H test, Pearson correlation analysis, and multiple linear regression. Results: We received 279 responses, out of which 37.28% experienced a high level of emotional exhaustion (EE), 13.62% had a high level of depersonalization (DP), and 19.71% experienced low levels of personal accomplishment (PA). EE had a significant negative correlation with the supervisor's support. In contrast, self-efficacy, hope, optimism, and resilience had a significant negative correlation with DP and a significant positive correlation with PA. Furthermore, supervisors' support significantly predicted lower levels of EE. Optimism significantly predicted lower levels of DP and higher levels of PA. Conclusions: Burnout is common among Togolese PCPs, and self-efficacy, optimism, and supervisors' support significantly contribute to low levels of job burnout among Togolese PCPs. This study provided insight into intervention programs to prevent burnout among PCPs in Togo.


Assuntos
Esgotamento Profissional , Pneumonia por Pneumocystis , Humanos , Estudos Transversais , Togo/epidemiologia , Esgotamento Psicológico , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Apoio Social , Inquéritos e Questionários , Atenção Primária à Saúde
6.
Phys Chem Chem Phys ; 24(42): 25788-25800, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36263785

RESUMO

Glucose oxidase (GOx) can catalyze the oxidation of ß-D-glucose under mild conditions to directly convert biological energy into electrical energy, which has great potential for applications in the fields of enzyme biofuel cells and glucose biosensors. In enzymatic biofuel cells, GOx is often used as an anodic catalyst to improve the performance. The important role of two intimate histidine residues, His505 and His548 (PDB code 4YNU), in the GOx active center has been highlighted in the catalytic oxidation of ß-D-glucose, but there is still a lack of systematic examination on the influence of different protonated states of His505 and His548 on the catalytic oxidation of ß-D-glucose in GOx. Therefore, in the present work, the GOx active center under the possible protonated states of His548 and His505 is systematically examined by using ONIOM calculations, as well as the influence of remote Arg210 is considered. The calculations reveal that the intimate His505 and His548 can modulate the interaction of the ß-D-glucose substrate with isoalloxazine and then control the deprotonization of the hydroxyl group bound to the anomeric carbon of ß-D-glucose like controllers. The remote Arg210 provides the driving force for the transfer of two electrons from ß-D-glucose to isoalloxazine of FAD via the long-range electrostatic attraction like a horse. Specially, the protonated His505 can serve as a good helper of Arg210 to promote the occurring of the two-proton-coupled two-electron transfer from ß-D-glucose to isoalloxazine and His548 in the active center of GOx. These findings provide much insight into the catalytic reactions of GOx in a low pH environment, which may be beneficial to expand the applications of GOx.


Assuntos
Fontes de Energia Bioelétrica , Glucose Oxidase , Cavalos , Animais , Glucose Oxidase/química , Histidina , Eletrodos , Glucose/química
7.
BMC Endocr Disord ; 22(1): 76, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35331213

RESUMO

BACKGROUND: Dyslipidaemia is a risk factor for abnormal blood glucose. However, studies on the predictive values of lipid markers in prediabetes and diabetes simultaneously are limited. This study aimed to assess the associations and predictive abilities of lipid indices and abnormal blood glucose. METHODS: A sample of 7667 participants without diabetes were enrolled in this cross-sectional study conducted in 2016, and all of them were classified as having normal glucose tolerance (NGT), prediabetes or diabetes. Blood glucose, blood pressure and lipid parameters (triglycerides, TG; total cholesterol, TC; high-density lipoprotein cholesterol, HDL-C; low-density lipoprotein cholesterol, LDL-C; non-high-density lipoprotein cholesterol, non-HDL-C; and triglyceride glucose index, TyG) were evaluated or calculated. Logistic regression models were used to analyse the association between lipids and abnormal blood glucose. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was used to assess the discriminatory power of lipid parameters for detecting prediabetes or diabetes. RESULTS: After adjustment for potential confounding factors, the TyG was the strongest marker related to abnormal blood glucose compared to other lipid indices, with odds ratios of 2.111 for prediabetes and 5.423 for diabetes. For prediabetes, the AUCs of the TG, TC, HDL-C, LDL-C, TC/HDL-C, TG/HDL-C, non-HDL-C and TyG indices were 0.605, 0.617, 0.481, 0.615, 0.603, 0.590, 0.626 and 0.660, respectively, and the cut-off points were 1.34, 4.59, 1.42, 2.69, 3.39, 1.00, 3.19 and 8.52, respectively. For diabetes, the AUCs of the TG, TC, HDL-C, LDL-C, TC/HDL-C, TG/HDL-C, non-HDL-C and TyG indices were 0.712, 0.679, 0.440, 0.652, 0.686, 0.692, 0.705, and 0.827, respectively, and the cut-off points were 1.35, 4.68, 1.42, 2.61, 3.44, 0.98, 3.13 and 8.80, respectively. CONCLUSIONS: The TyG, TG and non-HDL-C, especially TyG, are accessible biomarkers for screening individuals with undiagnosed diabetes.


Assuntos
Diabetes Mellitus , Estado Pré-Diabético , Biomarcadores/sangue , China/epidemiologia , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Transversais , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Humanos , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/epidemiologia , Triglicerídeos/sangue
8.
Can J Urol ; 29(1): 10992-11002, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35150221

RESUMO

INTRODUCTION: To determine whether marital status combined with race serve as prognostic factors for survival in localized prostate cancer. MATERIALS AND METHODS: Patients with localized prostate cancer were retrospectively extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Chi-square test was used to investigate the association between marital status combined with race and other variables. Gray's test was used to compare the cumulative incidence function of different variables. Multivariable analysis was conducted to assess prognostic factors after adjusting for other variables. RESULTS: A total of 207,219 patients with localized prostate cancer from the SEER database from 2010 to 2016 were eligible. We found that black or single patients had the highest risk of mortality (p < 0.001). When marital status and race were combined, single black patients had the worst prognosis after adjusting for other variables (hazard ratio = 1.93, 95% confidence interval: 1.58-2.35; p < 0.001). Married status had a prognostic advantage in all races. In the same marital groups, whites and Asians had lower risk of prostate cancer-specific mortality and other-cause mortality than blacks with married and single status (p < 0.001). CONCLUSIONS: Marital status and race serve as prognostic factors for localized prostate cancer. Blacks or single individuals had higher risk of mortality when considered independently, and single black patients had the worst prognosis. Furthermore, married status was an advantage in the same race group, and whites and Asians had lower risk than blacks with married and single status. Accordingly, the interaction between race and marital status on prostate cancer prognosis in clinical practice should be assessed carefully.


Assuntos
Neoplasias da Próstata , Humanos , Masculino , Estado Civil , Prognóstico , Estudos Retrospectivos , Programa de SEER , Taxa de Sobrevida
9.
BMC Genomics ; 22(1): 271, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33858340

RESUMO

BACKGROUND: Infestation by tea green leafhoppers (Empoasca (Matsumurasca) onukii) can cause a series of biochemical changes in tea leaves. As a typical cell-rupture feeder, E. onukii secretes proteases while using its stylet to probe the tender shoots of tea plants (Camellia sinensis). This study identified and analyzed proteases expressed specifically in the salivary gland (SG) and gut of E. onukii through enzymatic activity assays complemented with an integrated analysis of transcriptomic and proteomic data. RESULTS: In total, 129 contigs representing seven types of putative proteases were identified. Transcript abundance of digestive proteases and enzymatic activity assays showed that cathepsin B-like protease, cathepsin L-like protease, and serine proteases (trypsin- and chymotrypsin-like protease) were highly abundant in the gut but moderately abundant in the SG. The abundance pattern of digestive proteases in the SG and gut of E. onukii differed from that of other hemipterans, including Nilaparvata lugens, Laodelphax striatellus, Acyrthosiphum pisum, Halyomorpha halys and Nephotettix cincticeps. Phylogenetic analysis showed that aminopeptidase N-like proteins and serine proteases abundant in the SG or gut of hemipterans formed two distinct clusters. CONCLUSIONS: Altogether, this study provides insightful information on the digestive system of E. onukii. Compared to five other hemipteran species, we observed different patterns of proteases abundant in the SG and gut of E. onukii. These results will be beneficial in understanding the interaction between tea plants and E. onukii.


Assuntos
Microbioma Gastrointestinal , Hemípteros , Animais , Hemípteros/genética , Peptídeo Hidrolases/genética , Filogenia , Proteômica , Glândulas Salivares , Transcriptoma
10.
Proc Natl Acad Sci U S A ; 112(39): 12046-51, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26371311

RESUMO

Advances in protein therapy are hindered by the poor stability, inadequate pharmacokinetic (PK) profiles, and immunogenicity of many therapeutic proteins. Polyethylene glycol conjugation (PEGylation) is the most successful strategy to date to overcome these shortcomings, and more than 10 PEGylated proteins have been brought to market. However, anti-PEG antibodies induced by treatment raise serious concerns about the future of PEGylated therapeutics. Here, we demonstrate a zwitterionic polymer network encapsulation technology that effectively enhances protein stability and PK while mitigating the immune response. Uricase modified with a comprehensive zwitterionic polycarboxybetaine (PCB) network exhibited exceptional stability and a greatly prolonged circulation half-life. More importantly, the PK behavior was unchanged, and neither anti-uricase nor anti-PCB antibodies were detected after three weekly injections in a rat model. This technology is applicable to a variety of proteins and unlocks the possibility of adopting highly immunogenic proteins for therapeutic or protective applications.


Assuntos
Géis/química , Nanomedicina/métodos , Proteínas/química , Proteínas/uso terapêutico , Animais , Betaína/química , Géis/farmacocinética , Géis/uso terapêutico , Meia-Vida , Estabilidade Proteica , Proteínas/farmacocinética , Ratos , Urato Oxidase/química
11.
Int J Biometeorol ; 62(4): 565-574, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29086082

RESUMO

Hand, foot, and mouth disease (HFMD) is a significant public health issue in China and an accurate prediction of epidemic can improve the effectiveness of HFMD control. This study aims to develop a weather-based forecasting model for HFMD using the information on climatic variables and HFMD surveillance in Nanjing, China. Daily data on HFMD cases and meteorological variables between 2010 and 2015 were acquired from the Nanjing Center for Disease Control and Prevention, and China Meteorological Data Sharing Service System, respectively. A multivariate seasonal autoregressive integrated moving average (SARIMA) model was developed and validated by dividing HFMD infection data into two datasets: the data from 2010 to 2013 were used to construct a model and those from 2014 to 2015 were used to validate it. Moreover, we used weekly prediction for the data between 1 January 2014 and 31 December 2015 and leave-1-week-out prediction was used to validate the performance of model prediction. SARIMA (2,0,0)52 associated with the average temperature at lag of 1 week appeared to be the best model (R 2 = 0.936, BIC = 8.465), which also showed non-significant autocorrelations in the residuals of the model. In the validation of the constructed model, the predicted values matched the observed values reasonably well between 2014 and 2015. There was a high agreement rate between the predicted values and the observed values (sensitivity 80%, specificity 96.63%). This study suggests that the SARIMA model with average temperature could be used as an important tool for early detection and prediction of HFMD outbreaks in Nanjing, China.


Assuntos
Surtos de Doenças , Doença de Mão, Pé e Boca/epidemiologia , Modelos Teóricos , Tempo (Meteorologia) , China/epidemiologia , Previsões , Humanos
12.
Genomics ; 109(1): 58-66, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27867104

RESUMO

Tea production has been significantly impacted by the false-eye leafhopper, Empoasca vitis (Göthe), around Asia. To identify the key genes which are responsible for nutrition absorption, xenobiotic metabolism and immune response, the transcriptome of either alimentary tracts or bodies minus alimentary tract of E. vitis was sequenced and analyzed. Over 31 million reads were obtained from Illumina sequencing. De novo sequence assembly resulted in 52,182 unigenes with a mean size of 848nt. The assembled unigenes were then annotated using various databases. Transcripts of at least 566 digestion-, 224 detoxification-, and 288 immune-related putative genes in E. vitis were identified. In addition, relative expression of highly abundant transcripts was verified through quantitative real-time PCR. Results from this investigation provide genomic information about E. vitis, which will be helpful in further study of E. vitis biology and in the development of novel strategies to control this devastating pest.


Assuntos
Digestão/genética , Hemípteros/genética , Sistema Imunitário , Inativação Metabólica/genética , Transcriptoma , Animais , Hemípteros/imunologia , Hemípteros/metabolismo , Hemípteros/fisiologia , Ninfa/genética
13.
J Insect Sci ; 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29415259

RESUMO

The brown planthopper (BPH) Nilaparvata lugens is one of the most destructive insect pests in the rice fields of Asia. Like other hemipteran insects, BPH is not susceptible to Cry toxins of Bacillus thuringiensis (Bt) or transgenic rice carrying Bt cry genes. Lack of Cry receptors in the midgut is one of the main reasons that BPH is not susceptible to the Cry toxins. The main Cry-binding proteins (CBPs) of the susceptible insects are cadherin, aminopeptidase N (APN), and alkaline phosphatase (ALP). In this study, we analyzed and validated de novo assembled transcripts from transcriptome sequencing data of BPH to identify and characterize homologs of cadherin, APN, and ALP. We then compared the cadherin-, APN-, and ALP-like proteins of BPH to previously reported CBPs to identify their homologs in BPH. The sequence analysis revealed that at least one cadherin, one APN, and two ALPs of BPH contained homologous functional domains identified from the Cry-binding cadherin, APN, and ALP, respectively. Quantitative real-time polymerase chain reaction used to verify the expression level of each putative Cry receptor homolog in the BPH midgut indicated that the CBPs homologous APN and ALP were expressed at high or medium-high levels while the cadherin was expressed at a low level. These results suggest that homologs of CBPs exist in the midgut of BPH. However, differences in key motifs of CBPs, which are functional in interacting with Cry toxins, may be responsible for insusceptibility of BPH to Cry toxins.

14.
J Virol ; 89(22): 11203-12, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26311872

RESUMO

UNLABELLED: Insect-borne plant viruses cause significant agricultural losses and jeopardize sustainable global food production. Although blocking plant virus transmission would allow for crop protection, virus receptors in insect vectors are unknown. Here we identify membrane alanyl aminopeptidase N (APN) as a receptor for pea enation mosaic virus (PEMV) coat protein (CP) in the gut of the pea aphid, Acyrthosiphon pisum, using a far-Western blot method. Pulldown and immunofluorescence binding assays and surface plasmon resonance were used to confirm and characterize CP-APN interaction. PEMV virions and a peptide comprised of PEMV CP fused to a proline-rich hinge (-P-) and green fluorescent protein (CP-P-GFP) specifically bound to APN. Recombinant APN expressed in Sf9 cells resulted in internalization of CP-P-GFP, which was visualized by confocal microscopy; such internalization is an expected hallmark of a functional gut receptor. Finally, in assays with aphid gut-derived brush border membrane vesicles, binding of CP-P-GFP competed with binding of GBP3.1, a peptide previously demonstrated to bind to APN in the aphid gut and to impede PEMV uptake into the hemocoel; this finding supports the hypothesis that GBP3.1 and PEMV bind to and compete for the same APN receptor. These in vitro data combined with previously published in vivo experiments (S. Liu, S. Sivakumar, W. O. Sparks, W. A. Miller, and B. C. Bonning, Virology 401:107-116, 2010, http://dx.doi.org/10.1016/j.virol.2010.02.009) support the identification of APN as the first receptor in a plant virus vector. Knowledge of this receptor will provide for technologies based on PEMV-APN interaction designed to block plant virus transmission and to suppress aphid populations. IMPORTANCE: A significant proportion of global food production is lost to insect pests. Aphids, in addition to weakening plants by feeding on their sap, are responsible for transmitting about half of the plant viruses vectored by insects. Growers rely heavily on the application of chemical insecticides to manage both aphids and aphid-vectored plant viral disease. To increase our understanding of plant virus-aphid vector interaction, we provide in vitro evidence supporting earlier in vivo work for identification of a receptor protein in the aphid gut called aminopeptidase N, which is responsible for entry of the plant virus pea enation mosaic virus into the pea aphid vector. Enrichment of proteins found on the surface of the aphid gut epithelium resulted in identification of this first aphid gut receptor for a plant virus. This discovery is particularly important since the disruption of plant virus binding to such a receptor may enable the development of a nonchemical strategy for controlling aphid-vectored plant viruses to maximize food production.


Assuntos
Afídeos/virologia , Antígenos CD13/metabolismo , Proteínas do Capsídeo/metabolismo , Vírus de Plantas/genética , Receptores Virais/metabolismo , Animais , Anticorpos/imunologia , Antígenos CD13/imunologia , Linhagem Celular , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Insetos Vetores/virologia , Luteovirus/metabolismo , Microvilosidades/virologia , Vírus do Mosaico/genética , Doenças das Plantas/virologia , Ligação Proteica/fisiologia , Células Sf9 , Spodoptera , Vicia faba
15.
Cell Mol Neurobiol ; 36(1): 121-30, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26271288

RESUMO

Elevated ß-amyloid (Aß) is a hallmark of Alzheimer's disease (AD). Recent evidence has suggested that the receptor of advanced glycation end products (RAGE) is a key target for Aß-induced perturbation in AD, and blockade of RAGE significantly alleviates synaptic injury. Our previous study has suggested that ß-asarone could reduce neuronal apoptosis and improve memory deficits in ß-amyloid precursor protein and presenilin-1 (APP/PS1) double transgenic AD-model mice. In the present study, we evaluated the effects of ß-asarone on amyloidosis in APP/PS1 mice. We found that the survival of neurons of APP/PS1 mice was improved by ß-asarone, meanwhile, ß-asarone decreased Aß deposition and down-regulated Aß1-42 levels in cortex and hippocampus of APP/PS1 mice brain. Interestingly, the level of RAGE was also significantly down-regulated by ß-asarone. Our findings suggest that ß-asarone might be effective for the treatment of AD, and the decreasing effects of ß-asarone on Aß might associate with its down-regulation of RAGE.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Amiloidose/tratamento farmacológico , Anisóis/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Derivados de Alilbenzenos , Doença de Alzheimer/complicações , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Amiloidose/complicações , Amiloidose/patologia , Animais , Anisóis/administração & dosagem , Anisóis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/patologia , Modelos Animais de Doenças , Hipocampo/patologia , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Placa Amiloide/complicações , Placa Amiloide/tratamento farmacológico , Placa Amiloide/patologia , Presenilina-1/metabolismo
16.
Exp Cell Res ; 334(1): 136-45, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25882496

RESUMO

Epigenetic changes are involved in learning and memory, and histone deacetylase (HDAC) inhibitors are considered potential therapeutic agents for Alzheimer's disease (AD). We previously reported that (-)-epigallocatechin-3-gallate (EGCG) acts as an HDAC inhibitor. Here, we demonstrate that EGCG reduced ß-amyloid (Aß) accumulation in vitro and rescued cognitive deterioration in senescence-accelerated mice P8 (SAMP8) via intragastric administration of low- and high-dose EGCG (5 and 15 mg/kg, respectively) for 60 days. The AD brain has decreased levels of the rate-limiting degradation enzyme of Aß, neprilysin (NEP). We found an association between EGCG-induced reduction in Aß accumulation and elevated NEP expression. Further, NEP silencing prevented the EGCG-induced Aß downregulation. Our findings suggest that EGCG might be effective for treating AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Catequina/análogos & derivados , Transtornos Cognitivos/tratamento farmacológico , Neprilisina/metabolismo , Regulação para Cima/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Animais , Células CHO , Catequina/química , Catequina/farmacologia , Proliferação de Células , Células Cultivadas , Transtornos Cognitivos/metabolismo , Cricetulus , Modelos Animais de Doenças , Camundongos , Estereoisomerismo
17.
Lipids Health Dis ; 15(1): 171, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27716295

RESUMO

BACKGROUND: Several genome-wide association studies have discovered novel loci at chromosome 12q24, which includes mevalonate kinase (MVK), methylmalonic aciduria (cobalamin deficiency) cbIB type (MMAB), and potassium channel tetramerization domain-containing 10 (KCTD10), all of which influence HDL-cholesterol concentrations. However, there are few reports on the associations between these polymorphisms and HDL-C concentrations in Chinese population. This study aimed to evaluate the associations between functional polymorphisms in three genes (MVK, MMAB and KCTD10) and HDL-C concentrations, as well as coronary heart disease (CHD) susceptibility in Chinese individuals. METHODS: We systematically selected and genotyped 18 potentially functional polymorphisms in MVK, MMAB and KCTD10 by using the TaqMan OpenArray Genotyping System in a Chinese population including 399 dyslipidemia cases, 697 CHD cases and 465 controls. Multivariate logistic regression analyses were performed to estimate the relationship between the genotypes and dyslipidemia, CHD risk with adjustment of relevant confounders. RESULTS: Among six polymorphisms showing significant associations with dyslipidemia, the minor alleles of rs11066782 in KCTD10, rs11613718 in KCTD10 and rs11067233 in MMAB were significantly associated with a decreased risk of CHD (additive model: OR = 0.71, 95 % CI = 0.53-0.97, P = 0.029 for rs11066782; OR = 0.73, 95 % CI = 0.54-0.99, P = 0.044 for rs11613718 and OR = 0.57, 95 % CI = 0.40-0.80, P = 0.001 for rs11067233). Further combined analysis showed that individuals carrying "3-4" favorable alleles presented a 62 % (OR = 0.38, 95 % CI = 0.21-0.66) decreased risk of CHD compared with those carrying "0-2" favorable alleles. CONCLUSIONS: These findings suggest that rs11066782 in KCTD10, rs11613718 in KCTD10 and rs11067233 in MMAB may contribute to the susceptibility of CHD by altering plasma HDL-C levels in Han Chinese.


Assuntos
Alquil e Aril Transferases/genética , Doença das Coronárias/genética , Dislipidemias/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Adulto , Idoso , Alelos , HDL-Colesterol/sangue , HDL-Colesterol/genética , Doença das Coronárias/patologia , Dislipidemias/patologia , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
18.
Proc Natl Acad Sci U S A ; 110(21): 8465-70, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23650347

RESUMO

Although transgenic crops expressing Bacillus thuringiensis (Bt) toxins have been used successfully for management of lepidopteran and coleopteran pest species, the sap-sucking insects (Hemiptera) are not particularly susceptible to Bt toxins. To overcome this limitation, we demonstrate that addition of a short peptide sequence selected for binding to the gut of the targeted pest species serves to increase toxicity against said pest. Insertion of a 12-aa pea aphid gut-binding peptide by adding to or replacing amino acids in one of three loops of the Bt cytolytic toxin, Cyt2Aa, resulted in enhanced binding and toxicity against both the pea aphid, Acyrthosiphon pisum, and the green peach aphid, Myzus persicae. This strategy may allow for transgenic plant-mediated suppression of other hemipteran pests, which include some of the most important pests of global agriculture.


Assuntos
Afídeos/metabolismo , Bacillus thuringiensis , Proteínas de Bactérias , Endotoxinas , Proteínas Hemolisinas , Inseticidas , Mucosa Intestinal/metabolismo , Controle Biológico de Vetores/métodos , Animais , Afídeos/ultraestrutura , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Endotoxinas/biossíntese , Endotoxinas/genética , Endotoxinas/farmacologia , Proteínas Hemolisinas/biossíntese , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Inseticidas/metabolismo , Inseticidas/farmacologia , Intestinos/ultraestrutura , Larva/metabolismo , Larva/ultraestrutura
19.
Pharm Biol ; 54(10): 2127-34, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26957139

RESUMO

Context The roots of Ilex asprella (Hook. et Arn.) Champ. ex Benth. (Aquifoliaceae) are widely used in Chinese medicine to treat influenza, amygdalitis, pertussis, etc. Their mechanism of action is still unknown, which raises the need to identify new bioactive compounds in this plant. Objective In this study, we isolated a novel saponin containing sulphonic groups, namely, asprellcoside A (1) and a known phenolic glycoside compound (2) from the roots of Ilex asprella and evaluated their bioactivities. Materials and methods Molecular structures were elucidated by analysing their spectral and chemical properties. The viability of A549 cells was tested using a MTT assay. Ability of the compounds to inhibit viruses was determined using the neuraminidase activity assay. Their anti-inflammatory effects were tested using the IP-10 activity assay using various concentrations (compound 1: 0.6, 0.2, 0.6, 1.70, 5.00 and 15.00 µM; compound 2: 0.4, 1.2, 3.6, 11.0, 33.0 and 100 µM). Their inhibitory effect on platelet aggregation induced by adenosine diphosphate (ADP) in rabbit plasma was determined at 60 and 80 µM. Results Both compounds inhibit influenza virus strain A/PuertoRico/8/1934 (H1N1) strongly with EC50 values of 4.1 and 1.7 µM, respectively. Both compounds inhibit the secretion of IP-10 with EC50 values of 6.6 and 2.5 µM, respectively. Compound 1 alone inhibited platelet aggregation significantly, with the rate of suppression being 47 ± 8 and 38 ± 3%, at 60 and 80 µM, respectively. Conclusions The results suggest that both compounds may be valid therapeutics against influenza virus infection and that compound 1 may be a novel agent for treating thrombosis.


Assuntos
Anti-Inflamatórios/farmacologia , Antivirais/farmacologia , Glicosídeos/farmacologia , Extratos Vegetais/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Antivirais/química , Antivirais/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Cães , Relação Dose-Resposta a Droga , Glicosídeos/química , Glicosídeos/isolamento & purificação , Humanos , Ilex/química , Mediadores da Inflamação/metabolismo , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/enzimologia , Células Madin Darby de Rim Canino , Estrutura Molecular , Neuraminidase/antagonistas & inibidores , Neuraminidase/metabolismo , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Raízes de Plantas , Plantas Medicinais , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/isolamento & purificação , Coelhos , Relação Estrutura-Atividade
20.
J Gen Virol ; 96(Pt 7): 1821-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25838065

RESUMO

Infectious myonecrosis virus (IMNV) causes significant economic losses in farmed shrimp, where associated mortality in ponds can reach 70 %. To explore host/pathogen interactions, a next-generation sequencing approach using lymphoid organ tissue from IMNV-infected Litopenaeus vannamei shrimp was conducted. Preliminary sequence assembly of just the virus showed that there were at least an additional 639 bp at the 5' terminus and 23 nt at the 3' terminus as compared with the original description of the IMNV genome (7561 nt). Northern blot and reverse transcription-PCR analysis confirmed the presence of novel sequence at both ends of the genome. Using 5' RACE, an additional 4 nt were discovered; 3' RACE confirmed the presence of 22 bp rather than 23 bp of sequence. Based on these data, the IMNV genome is 8226 bp in length. dsRNA was used to trigger RNA interference (RNAi) and suppress expression of the newly revealed genome sections at the 5' end of the IMNV genome in IMNV-infected L. vannamei. An RNAi trigger targeting a 376 bp length of the 5' UTR did not improve survival of infected shrimp. In contrast, an RNAi trigger targeting a 381 bp sequence in ORF1 improved survival to 82.2 % as compared with 2.2 % survival in positive control animals. These studies revealed the importance of the new genome sections to produce high-titre infection, and associated disease and mortality, in infected shrimp.


Assuntos
Genoma Viral , Penaeidae/virologia , Totiviridae/genética , Animais , Northern Blotting , Dados de Sequência Molecular , Infecções por Vírus de RNA , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Análise de Sobrevida , Totiviridae/isolamento & purificação
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