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1.
Sensors (Basel) ; 23(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37177533

RESUMO

Lead sulfide colloidal quantum dots (PbS CQDs) are promising optoelectronic materials due to their unique properties, such as tunable band gap and strong absorption, which are of immense interest for application in photodetectors and solar cells. However, the tunable band gap of PbS CQDs would only cover visible short-wave infrared; the ability to detect longer wavelengths, such as mid- and long-wave infrared, is limited because they are restricted by the band gap of the bulk material. In this paper, a novel photodetector based on the synergistic effect of PbS CQDs and bismuth telluride (Bi2Te3) was developed for the detection of a mid-wave infrared band at room temperature. The device demonstrated good performance in the visible-near infrared band (i.e., between 660 and 850 nm) with detectivity of 1.6 × 1010 Jones at room temperature. It also exhibited photoelectric response in the mid-wave infrared band (i.e., between 4.6 and 5.1 µm). The facile fabrication process and excellent performance (with a response of up to 5.1 µm) of the hybrid Bi2Te3/PbS CQDS photodetector are highly attractive for many important applications that require high sensitivity and broadband light detection.

2.
Sensors (Basel) ; 23(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36850852

RESUMO

Quantum dots have found significant applications in photoelectric detectors due to their unique electronic and optical properties, such as tunable bandgap. Recently, colloidal quantum dots (CQDs) have attracted much interest because of the ease of controlling the dot size and low production cost. In this paper, a high-performance ZnO/PbS heterojunction photodetector was fabricated by spin-coating PbS CQDs onto the surface of a hydrothermally grown vertical array of ZnO nanowires (NWs) on an indium tin oxide (ITO) substrate. Under 940 nm near-infrared light illumination, the device demonstrated a responsivity and detectivity of ~3.9 × 104 A/W and ~9.4 × 1013 Jones, respectively. The excellent performances and low cost of this nanocomposite-based photodetector show that it has the potential for widespread applications ranging from medical diagnosis to environmental monitoring.

3.
Nanomaterials (Basel) ; 12(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36145000

RESUMO

Colloidal quantum dots (CQDs) as photodetector materials have attracted much attention in recent years due to their tunable energy bands, low cost, and solution processability. However, their intrinsically low carrier mobility and three-dimensional (3D) confinement of charges are unsuitable for use in fast-response and highly sensitive photodetectors, hence greatly restricting their application in many fields. Currently, 3D topological insulators, such as bismuth telluride (Bi2Te3), have been employed in high-speed broadband photodetectors due to their narrow bulk bandgap, high carrier mobility, and strong light absorption. In this work, the advantages of topological insulators and CQDs were realized by developing a hybrid Bi2Te3/PbS CQDs photodetector that exhibited a maximum responsivity and detectivity of 18 A/W and 2.1 × 1011 Jones, respectively, with a rise time of 128 µs at 660 nm light illumination. The results indicate that such a photodetector has potential application in the field of fast-response and large-scale integrated optoelectronic devices.

4.
Ann Transl Med ; 10(14): 762, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35965798

RESUMO

Background: Polycystic ovary syndrome (PCOS) is the most common reproductive endocrine disease in women of childbearing age, and insulin resistance is an important etiological mechanism in PCOS. This study revealed the microRNA (miRNA) expression profile of PCOS with insulin resistance and explored the potential biological functions of differentially expressed miRNA. Methods: A total of 76 patients with PCOS and 30 normal healthy women were recruited in the gynecological clinic of the Second Hospital of Tianjin Medical University. We divided the patients with PCOS into a group with insulin resistance (n=46) and a group without insulin resistance (n=30). Peripheral venous serum samples from each group were used for deep sequencing to identify differentially expressed miRNAs. Hierarchical clustering heat maps were used to show differences in miRNA expression. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and target gene network databases were used to explore the potential target genes of differentially expressed miRNAs and to analyze their specific biological functions. Results: A case-control analysis found that the levels of body mass index (BMI), prolactin (PRL), total testosterone (T), fasting blood glucose (FBG), and fasting insulin (INS) in patients with PCOS were higher than those in healthy controls. High BMI, high blood sugar, and hyperinsulinemia were more significant in the PCOS with insulin resistance group than without insulin resistance group. Among the patients with PCOS, miR-122-5p was found to have more significant differences in the PCOS with insulin resistance group. GO and KEGG pathway analysis showed that the identified miRNAs were involved in the regulation of different biological processes, such as signal transduction, negative regulation of GTPase activity, chloride channel complex. The predicted target genes were related to the citrate cycle (TCA cycle) and the biosynthesis of mucin-type O-glycans. Conclusions: Our research demonstrated the use of miRNAs as new biomarkers for the diagnosis, treatment and presented a new strategy to lessen the symptoms of PCOS with insulin resistance.

5.
J Integr Neurosci ; 21(2): 52, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35364640

RESUMO

BACKGROUND: Overactivation of the salience network (SN) causes hyperarousal in insomnia patients and is associated with sleep-onset insomnia (SOI). Resting-state microstate 3 (RS-MS3) duration is closely related to SN overactivation. However, whether RS-MS3 duration is a biomarker for SOI has not yet been reported in the literature. In addition, SN activity is also associated with efficiency. However, it is not clear whether there are individual differences in the neural mechanisms of SOI in different efficiency groups. METHODS: Considering that RS-MS3 duration characterizes the stability and persistent activation of the SN in the resting state, the current study investigated the link between SOI measured by sleep latency of Pittsburg Sleep Quality Index (PSQI), efficiency measured by Kirton Adaption-Innovation Inventory (KAI), and RS-MS3 in a Chinese healthy (subclinical) student population, using electroencephalography (EEG) microstate analysis. RESULTS: We found that RS-MS3 duration was positively correlated with sleep latency and efficiency. The interaction between sleep latency and efficiency was significant. Simple slope analysis showed that high sleep latency was positively correlated with longer RS-MS3 duration in participants with higher efficiency scores. This correlation did not exist in participants with low efficiency scores. CONCLUSIONS: RS-MS3 duration may serve as a biomarker for SOI. There is heterogeneity in the relationship between SOI and RS-MS3 duration between individuals with high and low efficiency.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Eletroencefalografia , Humanos , Sono/fisiologia , Distúrbios do Início e da Manutenção do Sono/complicações , Fatores de Tempo
6.
Medicine (Baltimore) ; 100(21): e25975, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34032709

RESUMO

ABSTRACT: This study aimed to evaluate the prevalence of low health literacy in Hebei Province of China, and to investigate its socio-demographic risk factors.This study was a community-based, cross-sectional questionnaire survey with a multiple-stage randomization design and a sample size of 10,560. Participants' health literacy status was evaluated by a questionnaire based on the 2012 Chinese Resident Health Literacy Scale. Meanwhile, participants' socio-demographic characteristics were also collected by the questionnaire.A total of 9952 participants provided valid questionnaires and were included in the final analyses. The mean health literacy score was 63.1 ±â€Š17.1 points; for its subscales, the mean basic knowledge and concepts score, lifestyle score, health-related skills score were 31.7 ±â€Š9.0, 17.2 ±â€Š4.8, 14.3 ±â€Š4.1, respectively. Meanwhile, low health literacy prevalence was 81.0%; for its subscales, low basic knowledge and concepts prevalence (70.6%) was numerically reduced compared to low lifestyle prevalence (87.4%) and low health-related skills prevalence (86.1%). Further analyses showed that age, male, and rural area were positively associated, but education level and annual household income were negatively associated with low health literacy prevalence. Further multivariate logistic regression analyses showed that higher age, male, lower education level, lower annual household income, and rural area were closely correlated with the risks of low total health literacy or low health literacy in subscales in Hebei Province.The prevalence of low health literacy is 81.0% in Hebei Province. Meanwhile, higher age, male, lower education level, lower annual household income, and rural area closely associate with low health literacy risk.


Assuntos
Letramento em Saúde/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , China , Estudos Transversais , Escolaridade , Feminino , Humanos , Renda , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Fatores de Risco , População Rural/estatística & dados numéricos , Fatores Sexuais , População Urbana/estatística & dados numéricos , Adulto Jovem
7.
Medicine (Baltimore) ; 100(10): e24848, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33725838

RESUMO

ABSTRACT: This study aimed to evaluate the low health literacy prevalence and its socio-demographic related factors in Xingtai.This study was a community-based, cross-sectional survey performed in Xingtai, with a sample size of 960. Participants' socio-demographic characteristics were collected, and their health literacy status was evaluated by the questionnaire designed by the 2012 Chinese Resident Health Literacy Survey.There were 904 (94.2%) participants who provided valid questionnaires and they were included in the analyses. The mean health literacy score was 63.0 ±â€Š16.6; for its subscales, the mean scores of health literacy of basic knowledge and concepts, lifestyle, and health-related skills were 31.6 ±â€Š8.7, 17.1 ±â€Š4.7, and 14.3 ±â€Š3.9, respectively. Low total health literacy prevalence was 83.1%; as for its subscales, the prevalence of low health literacy of basic knowledge and concepts, lifestyle, and health-related skills was 72.5%, 87.8%, and 87.4%, respectively. Meanwhile, age, male and rural location were positively correlated, but education level and annual household income were negatively correlated with low health literacy risk. Further multivariate analysis revealed that lower education level was the only independent related factor for low total health literacy, and the most important independent related factor for low total health literacy of basic knowledge and concepts, lifestyle and health-related skills.Low health literacy prevalence is 83.1%, and lower education level is the most critical related factor for low health literacy in Xingtai.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde/etnologia , Letramento em Saúde/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , China/epidemiologia , Estudos Transversais , Escolaridade , Feminino , Inquéritos Epidemiológicos , Humanos , Renda , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Prevalência , População Rural , Fatores Sexuais , População Urbana , Adulto Jovem
8.
J Diabetes Res ; 2016: 2340276, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27088095

RESUMO

The aim of this study was to assay the effects of Coreopsis tinctoria Nutt. flower extracts on hyperglycemia of diet-induced obese mice and the underlying mechanisms. Coreopsis tinctoria flower was extracted with ethanol and water, respectively. The total phenol, flavonoid levels, and the constituents of the extracts were measured. For the animal experiments, C57BL/6 mice were fed with a chow diet, high-fat diet, or high-fat diet mixed with 0.4% (w/w) water and ethanol extracts of Coreopsis tinctoria flower for 8 weeks. The inhibitory effects of the extracts on α-glucosidase activity and the antioxidant properties were assayed in vitro. We found that the extracts blocked the increase of fasting blood glucose, serum triglyceride (TG), insulin, leptin, and liver lipid levels and prevented the development of glucose tolerance impairment and insulin resistance in the C57BL/6 mice induced by a high-fat diet. The extracts inhibited α-glycosidase activity and increased oxidant activity in vitro. In conclusion, Coreopsis tinctoria flower extracts may ameliorate high-fat diet-induced hyperglycemia and insulin resistance. The underling mechanism may be via the inhibition of α-glucosidase activity. Our data indicate that Coreopsis tinctoria flower could be used as a beverage supplement and a potential source of drugs for treatment of diabetics.


Assuntos
Glicemia/efeitos dos fármacos , Coreopsis/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hiperglicemia/prevenção & controle , Extratos Vegetais/farmacologia , Animais , Biomarcadores/sangue , Glicemia/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Etanol/química , Feminino , Flores , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Hiperglicemia/sangue , Hiperglicemia/etiologia , Insulina/sangue , Resistência à Insulina , Leptina/sangue , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Obesidade/complicações , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Solventes/química , Fatores de Tempo , Água/química
9.
Diabetologia ; 59(6): 1276-86, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26983922

RESUMO

AIMS/HYPOTHESIS: Pan-peroxisome proliferator-activated receptor (PPAR) agonists have long been sought as therapeutics against the metabolic syndrome, but current PPAR agonists show limited efficacy and adverse effects. Natural herbs provide a structurally untapped resource to prevent and treat complicated metabolic syndrome. METHODS: Natural PPAR agonists were screened using reporter gene, competitive binding and 3T3-L1 pre-adipocyte differentiation assays in vitro. The effects on metabolic phenotypes were verified in db/db and diet-induced obese mice. In addition, potentially synergistic actions of bavachinin (BVC, a novel natural pan-PPAR agonist from the fruit of the traditional Chinese glucose-lowering herb malaytea scurfpea) and synthetic PPAR agonists were studied through nuclear magnetic resonance, molecular docking, reporter gene assays and mouse studies. RESULTS: BVC exhibited glucose-lowering properties without inducing weight gain and hepatotoxicity. Importantly, BVC synergised with thiazolidinediones, which are synthetic PPAR-γ agonists, and fibrates, which are PPAR-α agonists, to induce PPAR transcriptional activity, as well as to lower glucose and triacylglycerol levels in db/db mice. We further found that BVC occupies a novel alternative binding site in addition to the canonical site of synthetic agonists of PPAR, and that the synthetic PPAR-γ agonist rosiglitazone can block BVC binding to this canonical site but not to the alternative site. CONCLUSIONS/INTERPRETATION: This is the first report of a synergistic glucose- and lipid-lowering effect of BVC and synthetic agonists induced by unique binding with PPAR-γ or -α. This combination may improve the efficacy and decrease the toxicity of marketed drugs for use as adjunctive therapy to treat the metabolic syndrome.


Assuntos
Flavonoides/uso terapêutico , Obesidade/tratamento farmacológico , Obesidade/metabolismo , PPAR alfa/agonistas , Células 3T3-L1 , Animais , Sítios de Ligação , Glicemia/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Flavonoides/administração & dosagem , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , Obesidade/sangue , PPAR gama , Tiazolidinedionas/uso terapêutico , Triglicerídeos/sangue
10.
Int J Environ Res Public Health ; 13(4): 355, 2016 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-27023573

RESUMO

BACKGROUND: We previously proposed a hybrid model combining both the autoregressive integrated moving average (ARIMA) and the nonlinear autoregressive neural network (NARNN) models in forecasting schistosomiasis. Our purpose in the current study was to forecast the annual prevalence of human schistosomiasis in Yangxin County, using our ARIMA-NARNN model, thereby further certifying the reliability of our hybrid model. METHODS: We used the ARIMA, NARNN and ARIMA-NARNN models to fit and forecast the annual prevalence of schistosomiasis. The modeling time range included was the annual prevalence from 1956 to 2008 while the testing time range included was from 2009 to 2012. The mean square error (MSE), mean absolute error (MAE) and mean absolute percentage error (MAPE) were used to measure the model performance. We reconstructed the hybrid model to forecast the annual prevalence from 2013 to 2016. RESULTS: The modeling and testing errors generated by the ARIMA-NARNN model were lower than those obtained from either the single ARIMA or NARNN models. The predicted annual prevalence from 2013 to 2016 demonstrated an initial decreasing trend, followed by an increase. CONCLUSIONS: The ARIMA-NARNN model can be well applied to analyze surveillance data for early warning systems for the control and elimination of schistosomiasis.


Assuntos
Modelos Teóricos , Redes Neurais de Computação , Esquistossomose/epidemiologia , Estudos de Viabilidade , Previsões/métodos , Humanos , Modelos Estatísticos , Dinâmica não Linear , Prevalência , Reprodutibilidade dos Testes
11.
Sci Rep ; 6: 19288, 2016 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-26775807

RESUMO

Studies on peroxisome proliferator-activated receptor (PPAR)-γ ligands have been focused on agonists. However, PPARγ activation may induce obesity and nonalcoholic fatty liver disease (NAFLD), one of the most challenging medical conditions. Here, we identified that isorhamnetin, a naturally occurring compound in fruits and vegetables and the metabolite of quercetin, is a novel antagonist of PPARγ. Isorhamnetin treatment inhibited the adipocyte differentiation induced by the PPARγ agonist rosiglitazone, reduced obesity development and ameliorated hepatic steatosis induced by both high-fat diet treatment and leptin deficiency. Our results suggest that dietary supplement of isorhamnetin may be beneficial to prevent obesity and steatosis and PPARγ antagonists may be useful to treat hepatic steatosis.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Leptina/deficiência , Doenças Metabólicas/etiologia , Doenças Metabólicas/metabolismo , PPAR gama/antagonistas & inibidores , Quercetina/análogos & derivados , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Animais , Diferenciação Celular/efeitos dos fármacos , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Camundongos , Modelos Moleculares , Conformação Molecular , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/etiologia , Obesidade/metabolismo , PPAR gama/química , PPAR gama/metabolismo , Ligação Proteica , Quercetina/química , Quercetina/farmacologia , Ativação Transcricional
12.
AIDS Patient Care STDS ; 29(10): 541-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26270626

RESUMO

Few studies in China have focused on advanced human immunodeficiency virus (HIV) disease (AHD) and late entry to HIV care, which are associated with increased morbidity and mortality. A population-based retrospective study was conducted using 980 national HIV surveillance reports from 1994 to February 2012 in Wuhan, China. AHD was defined as presence of a first-reported CD4 count<200 cells/µL or an acquired immune deficiency syndrome (AIDS)-defining event within 1 month of HIV diagnosis. Late entry to HIV care was defined as patients with a first-reported CD4 cell count>6 months after diagnosis. Non-conditional logistic regression analysis was used to identify factors associated with AHD, late entry to HIV care, and AIDS within 1 year of HIV diagnosis. The proportions of AHD, AIDS within 1 year of HIV diagnosis, and late entry to HIV care were 29.49%, 39.39%, and 20.84%, respectively. Most of the deaths (74.27%, 127/171) occurred within 1 year of diagnosis. Short-term mortality, proportion of AHD, and late entry to HIV care showed a similar downward trend from pre-2003 to 2011 (p<0.001). Age, transmission category, sample source, and occupation were associated with AHD, late entry to HIV care, and AIDS within 1 year of HIV diagnosis in the multivariate logistic regression analysis. These findings indicate that AHD and late entry to HIV care were associated with an increased incidence of AIDS or death, particularly within 1 year of diagnosis. More effort should be made to assure early diagnosis and timely entry to care.


Assuntos
Sorodiagnóstico da AIDS/estatística & dados numéricos , Infecções por HIV/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adulto , Distribuição por Idade , Contagem de Linfócito CD4 , China/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Vigilância da População , Estudos Retrospectivos , Fatores de Risco , Fatores Socioeconômicos , Fatores de Tempo , Adulto Jovem
13.
Sci Rep ; 4: 7375, 2014 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-25487878

RESUMO

Obesity is prevalent worldwide, and is highly associated with metabolic disorders, such as insulin resistance, hyperlipidemia and steatosis. Ginseng has been used as food and traditional herbal medicine for the treatment of various metabolic diseases. However, the molecular mechanisms how ginseng and its components participate in the regulation of lipogenesis are still largely unclear. Here, we identified that protopanaxatriol (PPT), a major ginseng constituent, inhibited rosiglitazone-supported adipocyte differentiation of 3T3-L1 cells by repressing the expression of lipogenesis-related gene expression. In high-fat diet-induced obesity (DIO) mice, PPT reduced body weight and serum lipid levels, improved insulin resistance, as well as morphology and lipid accumulation, particular macrovesicular steatosis, in the livers. These effects were confirmed with genetically obese ob/ob mice. A reporter gene assay showed that PPT specifically inhibited the transactivity of PPARγ, but not PPAR α, ß/δ and LXR α, ß. TR-FRET assay revealed that PPT was specifically bound to PPARγ LBD, which was further confirmed by the molecular docking study. Our data demonstrate that PPT is a novel PPARγ antagonist. The inhibition of PPARγ activity could be a promising therapy for obesity and steatosis. Our findings shed new light on the mechanism of ginseng in the treatment of metabolic syndrome.


Assuntos
Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , PPAR gama/antagonistas & inibidores , Panax/química , Sapogeninas/farmacologia , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Animais , Diferenciação Celular/efeitos dos fármacos , Dieta Hiperlipídica , Modelos Animais de Doenças , Transporte de Elétrons , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/genética , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/genética , Inflamação/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Obesidade/tratamento farmacológico , Obesidade/etiologia , Obesidade/metabolismo , PPAR gama/metabolismo
14.
PLoS One ; 9(8): e104875, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25119882

RESUMO

BACKGROUNDS/OBJECTIVE: Schistosomiasis is still a major public health problem in China, despite the fact that the government has implemented a series of strategies to prevent and control the spread of the parasitic disease. Advanced warning and reliable forecasting can help policymakers to adjust and implement strategies more effectively, which will lead to the control and elimination of schistosomiasis. Our aim is to explore the application of a hybrid forecasting model to track the trends of the prevalence of schistosomiasis in humans, which provides a methodological basis for predicting and detecting schistosomiasis infection in endemic areas. METHODS: A hybrid approach combining the autoregressive integrated moving average (ARIMA) model and the nonlinear autoregressive neural network (NARNN) model to forecast the prevalence of schistosomiasis in the future four years. Forecasting performance was compared between the hybrid ARIMA-NARNN model, and the single ARIMA or the single NARNN model. RESULTS: The modelling mean square error (MSE), mean absolute error (MAE) and mean absolute percentage error (MAPE) of the ARIMA-NARNN model was 0.1869 × 10(-4), 0.0029, 0.0419 with a corresponding testing error of 0.9375 × 10(-4), 0.0081, 0.9064, respectively. These error values generated with the hybrid model were all lower than those obtained from the single ARIMA or NARNN model. The forecasting values were 0.75%, 0.80%, 0.76% and 0.77% in the future four years, which demonstrated a no-downward trend. CONCLUSION: The hybrid model has high quality prediction accuracy in the prevalence of schistosomiasis, which provides a methodological basis for future schistosomiasis monitoring and control strategies in the study area. It is worth attempting to utilize the hybrid detection scheme in other schistosomiasis-endemic areas including other infectious diseases.


Assuntos
Monitoramento Epidemiológico , Previsões/métodos , Esquistossomose/epidemiologia , Saúde da População Urbana/estatística & dados numéricos , China/epidemiologia , Humanos , Modelos Estatísticos , Prevalência
15.
PLoS One ; 9(6): e98241, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24893000

RESUMO

BACKGROUND: Outbreaks of hand-foot-mouth disease (HFMD) have been reported for many times in Asia during the last decades. This emerging disease has drawn worldwide attention and vigilance. Nowadays, the prevention and control of HFMD has become an imperative issue in China. Early detection and response will be helpful before it happening, using modern information technology during the epidemic. METHOD: In this paper, a hybrid model combining seasonal auto-regressive integrated moving average (ARIMA) model and nonlinear auto-regressive neural network (NARNN) is proposed to predict the expected incidence cases from December 2012 to May 2013, using the retrospective observations obtained from China Information System for Disease Control and Prevention from January 2008 to November 2012. RESULTS: The best-fitted hybrid model was combined with seasonal ARIMA [Formula: see text] and NARNN with 15 hidden units and 5 delays. The hybrid model makes the good forecasting performance and estimates the expected incidence cases from December 2012 to May 2013, which are respectively -965.03, -1879.58, 4138.26, 1858.17, 4061.86 and 6163.16 with an obviously increasing trend. CONCLUSION: The model proposed in this paper can predict the incidence trend of HFMD effectively, which could be helpful to policy makers. The usefulness of expected cases of HFMD perform not only in detecting outbreaks or providing probability statements, but also in providing decision makers with a probable trend of the variability of future observations that contains both historical and recent information.


Assuntos
Doença de Mão, Pé e Boca/epidemiologia , Modelos Estatísticos , Redes Neurais de Computação , Dinâmica não Linear , Estações do Ano , Pré-Escolar , China/epidemiologia , Demografia , Epidemias , Feminino , Previsões , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Análise de Regressão , Reprodutibilidade dos Testes , Fatores de Tempo
16.
J Nutr Biochem ; 25(7): 702-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24746837

RESUMO

Okra is an important tropical vegetable and source of dietary medicine. Here, we assayed the effects of an ethanol extract of okra (EO) and its major flavonoids isoquercitrin and quercetin 3-O-gentiobioside on metabolic disorders in high-fat diet-induced obese mouse. We found that treatment with EO, isoquercitrin and quercetin 3-O-gentiobioside reduced blood glucose and serum insulin levels and improved glucose tolerance in obese mice. Meanwhile, serum triglyceride levels and liver morphology in the mice were significantly ameliorated by EO and isoquercitrin treatment. Total cholesterol levels in isoquercitrin and quercetin 3-O-gentiobioside treated mice were also reduced. We also found that EO inhibited the expression of nuclear receptor transcription factor PPARγ, which is an important regulator of lipid and glucose homeostasis. Furthermore, we determined that EO and quercetin 3-O-gentiobioside have antioxidant activity in vitro. Our results indicate that okra may serve as a dietary therapy for hyperglycemia and hypertriglyceridemia.


Assuntos
Abelmoschus/química , Dissacarídeos/farmacologia , Extratos Vegetais/farmacologia , Quercetina/análogos & derivados , Animais , Glicemia/metabolismo , Dieta Hiperlipídica , Feminino , Insulina/sangue , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/metabolismo , PPAR gama/antagonistas & inibidores , Quercetina/farmacologia
17.
Molecules ; 12(3): 552-62, 2007 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-17851410

RESUMO

The flavonoid phlorhizin is abundant in the leaves of Sweet Tea (ST, Lithocarpus Polystachyus Rehd). Phlorhizin was preparatively separated and purified from a crude ST extract containing 40% total flavonoids by static adsorption and dynamic desorption on ADS-7 macroporous resin and neutral alumina column chromatography. Only water and ethanol were used as solvents and eluants throughout the whole separation and purification process. Using a phlorhizin standard as the reference compound, the target compound separated from the crude ST extracts was analyzed by thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and electrospray ionization mass spectrometry (EIS-MS) and identified as 99.87% pure (by HPLC-UV) phlorhizin. The results showed that 10 g of the target compound could be obtained from 40 g of the crude extracts in a single operation, indicating a 40% recovery. Therefore, this represents an efficient and environmentally-friendly technology for separating and purifying phlorhizin from ST leaves.


Assuntos
Misturas Complexas/química , Fagaceae/química , Flavonoides/isolamento & purificação , Florizina/isolamento & purificação , Adsorção , Óxido de Alumínio , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Flavonoides/química , Glucosídeos/química , Florizina/química , Extratos Vegetais/química , Soluções , Espectrometria de Massas por Ionização por Electrospray , Fatores de Tempo
18.
Planta Med ; 68(2): 115-8, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11859459

RESUMO

Screening of natural products with anti-tumor activity as telomerase inhibitor is a new subject in the field of tumor therapy. Using telomerase PCR ELISA, telomere DNA hybridization and flow cytometry analysis, the effects of verbascoside, a phenylpropanoid glucoside extracted from Pedicularis striata Pall, on telomerase activity, telomere length and cell cycle of human gastric carcinoma cells MKN45 was examined in vitro. After being treated with a 50 % inhibition concentration of verbascoside (17.8 microg/ml), telomerase activity in the cells was significantly inhibited but not in the cellular supernatant, the average telomere length became remarkably short, and the sub-G0 /G1 peak and G2/M arrest were also displayed when compared to the control cells. These results suggest that verbascoside mediated-cell differentiation and apoptosis may be affected by telomere-telomerase-cell cycle dependent modulation. Thus, the antitumor mechanism of verbascoside is demonstrated once more by its inhibiting effect on telomerase activity in tumor cells, and the telomerase assay may provide a valuable screening method for antitumor activity of natural products.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Glucosídeos/farmacologia , Fenóis/farmacologia , Telomerase/efeitos dos fármacos , Telômero/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Extratos Vegetais/farmacologia , Reação em Cadeia da Polimerase , Scrophulariaceae , Telomerase/metabolismo , Telômero/genética , Telômero/metabolismo , Células Tumorais Cultivadas
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