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1.
ACS Nano ; 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32338865

RESUMO

The role of additives in facilitating the growth of conventional semiconducting thin films is well-established. Apparently, their presence is also decisive in the growth of two-dimensional transition metal dichalcogenides (TMDs), yet their role remains ambiguous. In this work, we show that the use of sodium bromide enables synthesis of TMD monolayers via a surfactant-mediated growth mechanism, without introducing liquefaction of metal oxide precursors. We discovered that sodium ions provided by sodium bromide chemically passivate edges of growing molybdenum disulfide crystals, relaxing in-plane strains to suppress 3D islanding and promote monolayer growth. To exploit this growth model, molybdenum disulfide monolayers were directly grown into desired patterns using predeposited sodium bromide as a removable template. The surfactant-mediated growth not only extends the families of metal oxide precursors but also offers a way for lithography-free patterning of TMD monolayers on various surfaces to facilitate fabrication of atomically thin electronic devices.

2.
Nucleic Acids Res ; 48(D1): D148-D154, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31647101

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs (typically consisting of 18-25 nucleotides) that negatively control expression of target genes at the post-transcriptional level. Owing to the biological significance of miRNAs, miRTarBase was developed to provide comprehensive information on experimentally validated miRNA-target interactions (MTIs). To date, the database has accumulated >13,404 validated MTIs from 11,021 articles from manual curations. In this update, a text-mining system was incorporated to enhance the recognition of MTI-related articles by adopting a scoring system. In addition, a variety of biological databases were integrated to provide information on the regulatory network of miRNAs and its expression in blood. Not only targets of miRNAs but also regulators of miRNAs are provided to users for investigating the up- and downstream regulations of miRNAs. Moreover, the number of MTIs with high-throughput experimental evidence increased remarkably (validated by CLIP-seq technology). In conclusion, these improvements promote the miRTarBase as one of the most comprehensively annotated and experimentally validated miRNA-target interaction databases. The updated version of miRTarBase is now available at http://miRTarBase.cuhk.edu.cn/.

3.
Artigo em Inglês | MEDLINE | ID: mdl-30499423

RESUMO

AIM: The study was conducted in order to examine the sex-specific association of serum uric acid (SUA) levels with elevated serum alanine aminotransferase (ALT) in a Taiwanese military cohort. METHODS: We made a cross-sectional examination of the sex-specific relationship using 6728 men and 766 women, aged 18-50 years from a large military cohort in Taiwan. SUA levels within the reference range (<7.0 mg/dL for men and <5.7 mg/dL for women respectively) were divided into quartiles and SUA levels greater than the upper reference limits were defined as hyperuricemia. Elevated ALT levels were defined as ≥40 U/L. Multivariate logistic regression analysis was performed to determine the association between each SUA category and elevated ALT levels in men and women, respectively. RESULTS: The prevalence of hyperuricemia and elevated ALT in men were 18.7% and 12.7%, respectively, and in women were 3.3% and 2.1%, respectively. As compared with the lowest SUA quartile, hyperuricemia was associated with elevated ALT in men (odds ratios (OR): 1.62, 95% confidence intervals (CI): 1.19-2.20) after controlling for age, service specialty, body mass index, metabolic syndrome components, current cigarette smoking, alcohol intake status, and weekly exercise times, but the associations for the other SUA quartiles were null. By contrast, the associations of hyperuricemia (OR: 0.81, 95% CI: 0.10-6.64) and the other SUA quartiles with elevated ALT were null in women. CONCLUSION: Our findings suggest that the relationship between each SUA level and elevated ALT may differ by sex among military young adults. The mechanism for the sex difference requires further investigations.


Assuntos
Alanina Transaminase/sangue , Aptidão Cardiorrespiratória/fisiologia , Militares , Caracteres Sexuais , Ácido Úrico/sangue , Adolescente , Adulto , Biomarcadores/sangue , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
4.
Br J Gen Pract ; 69(679): e112-e126, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30455220

RESUMO

BACKGROUND: The incidence of oral cancer is increasing. Guidance for oral cancer from the National Institute for Health and Care Excellence (NICE) is unique in recommending cross-primary care referral from GPs to dentists. AIM: This review investigates knowledge about delays in the diagnosis of symptomatic oral squamous cell carcinoma (OSCC) in primary care. DESIGN AND SETTING: An independent multi-investigator literature search strategy and an analysis of study methodologies using a modified data extraction tool based on Aarhus checklist criteria relevant to primary care. METHOD: The authors conducted a focused systematic review involving document retrieval from five databases up to March 2018. Included were studies looking at OSCC diagnosis from when patients first accessed primary care up to referral, including length of delay and stage of disease at time of definitive diagnosis. RESULTS: From 538 records, 16 articles were eligible for full-text review. In the UK, more than 55% of patients with OSCC were referred by their GP, and 44% by their dentist. Rates of prescribing between dentists and GPs were similar, and both had similar delays in referral, though one study found greater delays attributed to dentists as they had undertaken dental procedures. On average, patients had two to three consultations before referral. Less than 50% of studies described the primary care aspect of referral in detail. There was no information on inter-GP-dentist referrals. CONCLUSION: There is a need for primary care studies on OSCC diagnosis. There was no evidence that GPs performed less well than dentists, which calls into question the NICE cancer option to refer to dentists, particularly in the absence of robust auditable pathways.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Diagnóstico Tardio/estatística & dados numéricos , Neoplasias Bucais/diagnóstico , Atenção Primária à Saúde , Encaminhamento e Consulta/estatística & dados numéricos , Tempo para o Tratamento/estatística & dados numéricos , Protocolos Clínicos , Bases de Dados Factuais , Humanos , Atenção Primária à Saúde/estatística & dados numéricos , Fatores de Tempo
5.
Artigo em Inglês | MEDLINE | ID: mdl-29562671

RESUMO

The association of metabolic syndrome (MetS) components with elevated serum alanine aminotransferase (ALT) levels, a marker of hepatic injury, may differ between men and women. However, the sex-specific association in a military young population which has a low prevalence of MetS was unclear. We conducted a cross-sectional examination in 6738 men and 766 women, aged 18-50 years, from the cardiorespiratory fitness study in armed forces (CHIEF) in eastern Taiwan. The components of MetS were defined according to the updated International Diabetes Federation (IDF) ethnic criteria for Asians. Elevated ALT levels were defined as ≥40 U/L for both sexes and ≥30 U/L for women alternatively. Multivariate logistic regression analysis was performed to determine the sex-specific association between MetS components and elevated ALT. The prevalence of MetS and elevated ALT in men were 11.9% and 12.7% respectively, and in women were 3.5%, and 3.8% respectively. In men, high-density lipoprotein < 40 mg/dL, blood pressures ≥ 130/85 mmHg, serum triglycerides ≥ 150 mg/dL, and waist size ≥ 90 cm were associated with elevated ALT (odds ratios (OR) and 95% confidence intervals: 1.59 (1.34-1.90), 1.40 (1.19-1.65), 2.00 (1.68-2.39), and 1.68 (1.38-2.04); all p < 0.001); whereas in women, only fasting plasma glucose ≥ 100 mg/dL was associated with elevated ALT ≥ 40 U/L (OR: 7.59 (2.35-24.51), p = 0.001) and ALT ≥ 30 U/L (2.67 (0.89-7.95), p = 0.08). Our findings suggest that the relationship between metabolic abnormalities and elevated ALT may differ by sex, possibly due to the MetS more prevalent in young adult men than in women.


Assuntos
Alanina Transaminase/sangue , Síndrome Metabólica/sangue , Militares , Adolescente , Adulto , Grupo com Ancestrais do Continente Asiático , Biomarcadores/sangue , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Caracteres Sexuais , Taiwan/epidemiologia , Adulto Jovem
6.
World J Gastroenterol ; 23(25): 4587-4594, 2017 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-28740347

RESUMO

AIM: To investigate the association of chronic hepatitis B and nonalcoholic steatohepatitis with physical fitness in a Taiwanese military male cohort. METHODS: We made a cross-sectional examination of this association using 3669 young adult military males according to cardiorespiratory fitness and hospitalization events recorded in the Taiwan Armed Forces study. Cases of chronic hepatitis B (n = 121) were defined by personal history and positive detection of hepatitis B surface antigen. Cases of nonalcoholic steatohepatitis (n = 129) were defined by alanine transaminase level > 60 U/L, liver ultrasound finding of steatosis, and absence of viral hepatitis A, B or C infection. All other study participants were defined as unaffected (n = 3419). Physical fitness was evaluated by performance in 3000-m run, 2-min sit-ups, and 2-min push-ups exercises, with all the procedures standardized by a computerized scoring system. Multiple linear regression analysis was used to determine the relationship. RESULTS: Chronic hepatitis B negatively correlated with 2-min push-up numbers (ß = -2.49, P = 0.019) after adjusting for age, service specialty, body mass index, systolic and diastolic blood pressures, current cigarette smoking, alcohol intake status, serum hemoglobin, and average weekly exercise times. Nonalcoholic steatohepatitis was borderline positively correlated with 3000-m running time (ß = 11.96, P = 0.084) and negatively correlated with 2-min sit-up numbers (ß = -1.47, P = 0.040). CONCLUSION: Chronic hepatitis B viral infection and nonalcoholic steatohepatitis affects different physical performances in young adult military males, and future study should determine the underlying mechanism.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B Crônica/fisiopatologia , Militares/estatística & dados numéricos , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Aptidão Física/fisiologia , Adulto , Alanina Transaminase/sangue , Índice de Massa Corporal , Estudos Transversais , Exercício Físico , Hepacivirus/isolamento & purificação , Vírus da Hepatite A Humana/isolamento & purificação , Antígenos de Superfície da Hepatite B/isolamento & purificação , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/virologia , Humanos , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Prevalência , Estudos Retrospectivos , Taiwan/epidemiologia , Ultrassonografia , Adulto Jovem
7.
Am J Cancer Res ; 7(7): 1606-1616, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28744408

RESUMO

OBJECTIVES: The aim of this study was to investigate the effect of thiazolidinediones (TZDs) on the risk of hepatocellular carcinoma (HCC) development among diabetes mellitus (DM) patients. METHODS: We conducted a population-based case-control study in Taiwan based on data from the Taiwan National Health Insurance Research Database. A total of 76,349 newly diagnosed DM patients were identified from claims between 2000 and 2010. Among diabetics, 3,026 and 12,104 patients respectively, received or did not receive TZDs. Comparison frequency was matched with age, sex, and index date, excluding those with cancer at baseline. The incidence of HCC at the end of 2010 and the risks associated with the presence of hepatitis B and C infections were analyzed. The effect of TZDs use on the reduction of HCC risk was also assessed. RESULTS: The incidence of HCC was lower in the TZD cohort compared with the non-TZD cohort (418.3 vs. 484.6 per 100,000 person-years), with an adjusted hazard ratio (HR) of 0.53 (95% confidence interval = 0.38-0.77) using multivariable Cox proportional hazard regression. In the stratified analysis, HCC risk reduction was greater for diabetics without the comorbidities of cirrhosis, hepatitis B, hepatitis C, nonalcoholic fatty liver disease, end-stage renal disease, and hyperlipidemia, in the TZD cohort than in the non-TZD cohort. Male sex, cirrhosis, hepatitis B, and hepatitis C were significant independent factors predicting HCC (HRs of 1.43, 13.96, 2.31, and 2.15, respectively). CONCLUSIONS: This study suggests that the use of TZDs may reduce the risk of developing HCC among DM patients. Comorbidity with cirrhosis and/or hepatitis B/C infection appears to be associated with an extremely increased risk of developing HCC in this patient subset. These high-risk patients should be closely monitored.

8.
ACS Appl Mater Interfaces ; 9(1): 479-486, 2017 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-27978621

RESUMO

Here we report a simple, scalable, and low-cost method to enhance the electrochemical properties of Mn oxide electrodes for highly efficient and flexible symmetrical supercapacitors. The method involving printing on a printer, pencil-drawing, and electrodeposition is established to fabricate Mn oxide/Ni-nanotube/graphite/paper hybrid electrodes operating with a low-cost, novel urea-LiClO4/PVA as gel electrolyte for flexible solid-state supercapacitor (FSSC) devices. The Mn oxide nanofiber/Ni-nanotube/graphite/paper (MNNGP) electrodes in urea-LiClO4/PVA gel electrolyte show specific capacitance (Csp) 960 F/g in voltage region 0.8 V at 5 mV/s and exhibit excellent rates of capacitance retention more than 85% after 5000 cycles. Moreover, the electrochemical behavior of the MNNGP electrodes in urea-LiClO4/PVA at operating temperatures 27-110 °C was investigated; the results show that the MNNGP electrodes in urea-LiClO4/PVA exhibit outstanding performance (1100 F/g), even at 90 °C. The assembled FSSC devices based on the MNNGP electrodes in urea-LiClO4/PVA exhibit great Csp (380 F/g in potential region of 2.0 V at 5 mV/s, exhibiting superior energy density 211.1 W h/kg) and great cycle stability (less than 15% loss after 5000 cycles at 25 mV/s). The oxidation-state change was examined by in situ X-ray absorption spectroscopy. FSSC devices would open new opportunities in developing novel portable, wearable, and roll-up electric devices owing to the cheap, high-performance, wide range of operating temperature, and simple procedures for large-area fabrication.

9.
World J Cardiol ; 8(8): 464-71, 2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27621774

RESUMO

AIM: To investigate the association between cardiorespiratory fitness and hospitalization events in a cohort of large voluntary arm forces in Taiwan. METHODS: The cardiorespiratory fitness and hospitalization events in armed forces (CHIEF) is a retrospective cohort consisting of more than 4000 professional military members aged 18-50 years in Eastern Taiwan. All participants received history taking, physical examination, chest radiography, 12-lead electrocardiography, blood tests for cell counts and fasting glucose, lipid profiles, uric acid, renal function and liver function in the Hualien Armed Forces General Hospital during 2014. In addition, participants were required to undergo two indoor resistant exercise tests including 2-min push-up and 2-min sit-up, both scored by infrared sensing, and one outdoor endurance 3000-m none weight-bearing running test, the main indicator of cardiorespiratory fitness in the Military Physical Training and Testing Center in Eastern Taiwan in 2014. RESULTS: Hospitalization events for cardiovascular disease, acute kidney injury, rhabdomyolysis, severe infectious disease, acute psychiatric illness, diabetes, orthopedic surgery and mortality will be identified in the National Insurance Research Database for 10 years. CONCLUSION: CHIEF will be among the largest Eastern Asian armed forces cohort, in which physical status was strictly evaluated to follow up the hospitalization events for severe illness.

10.
World J Hepatol ; 7(10): 1412-20, 2015 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-26052386

RESUMO

Hepatocellular carcinoma (HCC) is the fifth most common form of human cancer worldwide and the third most common cause of cancer-related deaths. The strategies of various treatments for HCC depend on the stage of tumor, the status of patient's performance and the reserved hepatic function. The Barcelona Clinic Liver Cancer (BCLC) staging system is currently used most for patients with HCC. For example, for patients with BCLC stage 0 (very early stage) and stage A (early stage) HCC, the curable treatment modalities, including resection, transplantation and radiofrequency ablation, are taken into consideration. If the patients are in BCLC stage B (intermediate stage) and stage C (advanced stage) HCC, they may need the palliative transarterial chemoembolization and even the target medication of sorafenib. In addition, symptomatic treatment is always recommended for patients with BCLC stage D (end stage) HCC. In this review, we will attempt to summarize the historical perspective and the current developments of systemic therapies in BCLC stage B and C in HCC.

11.
J Nanosci Nanotechnol ; 10(8): 5456-60, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21125918

RESUMO

Visible light active photocatalysts were successfully prepared by incorporating chromium into anatase TiO2 at two Cr/Ti atomic ratios (0.03% and 0.11%) by the use of a modified sol-gel process. Results show that the size of the chromium modified TiO2 particles is approximately 14-25 nm. As indicated by diffuse reflectance ultra violet/visible absorption spectra, heavier chromium dosage tends to result in greater absorption in both ultra violet and visible light. The simulation results from Cr K-edge X-ray absorption spectra suggest that Cr(0) and Cr(III), accounting for approximately 25% and 75% of total Cr, respectively, coexist in the TiO2 catalyst doped with 0.11% Cr. Cr dopant is suggested to be responsible for the phenomenon of enhanced light absorption in both ultra violet and visible regions. Further, Cr(0) can act as an electron remover because of the formation of the Schottky barrier between Cr(0) and TiO2, thus reducing the possibility of electron hole recombination. Photo-catalytic degradation of methylene blue under irradiation of blue light (with peak flux at 460 nm wavelength and a small flux near 367 nm) was considerably enhanced under appropriate reaction time (12 and 24 h) as small amount of Cr was doped into anatase titanium dioxide catalyst. After prolonged reaction time, Cr(0) was suggested to be poisoned and/or oxidized by SO4(2-), one of the final products of mineralizing methylene blue, thus loosing the capability of the electron hole separation.

12.
J Synchrotron Radiat ; 17(2): 173-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20157268

RESUMO

Cr(VI) chemical reduction in natural organic matter (NOM)-bearing latosol soil was investigated under various heating conditions at < or = 378 K. An enhanced Cr(VI) reduction rate has been observed for the reaction at 353-378 K. The effect of Fe(II) naturally occurring in the latosol soil on Cr(VI) chemical reduction is negligible compared with the effect of NOM. Cr(OH)(3) was quantitatively specified by X-ray absorption spectroscopy to be the key chromium species ( approximately 80%) after approximately 90% of Cr(VI) was chemically reduced by NOM at 353-378 K. This study indicates a potential strategy for using the heat extracted from industrial flue gas with a heat exchanger to chemically reduce Cr(VI) in NOM-bearing or organics-amended soils that contain Cr(VI).


Assuntos
Cromo/química , Solo/análise , Compostos Ferrosos/química , Temperatura Alta , Oxirredução , Poluentes do Solo/análise , Espectroscopia por Absorção de Raios X
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