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1.
Arch Toxicol ; 98(3): 779-790, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38224356

RESUMO

Hair analysis is a crucial method in forensic toxicology with potential applications in revealing doping histories in sports. Despite its widespread use, knowledge about detectable substances in hair is limited. This study systematically assessed the detectability of prohibited substances in sports using a multifaceted approach. Initially, an animal model received a subset of 17 model drugs to compare dose dependencies and detection windows across different matrices. Subsequently, hair incorporation data from the animal experiment were extrapolated to all substances on the World Anti-Doping Agency's List through in-silico prediction. The detectability of substances in hair was further validated in a proof-of-concept human study involving the consumption of diuretics and masking agents. Semi-quantitative analysis of substances in specimens was performed using ultra-performance liquid chromatography-tandem mass spectrometry. Results showed plasma had optimal dose dependencies with limited detection windows, while urine, faeces, and hair exhibited a reasonable relationship with the administered dose. Notably, hair displayed the highest detection probability (14 out of 17) for compounds, including anabolic agents, hormones, and diuretics, with beta-2 agonists undetected. Diuretics such as furosemide, canrenone, and hydrochlorothiazide showed the highest hair incorporation. Authentic human hair confirmed diuretic detectability, and their use duration was determined via segmental analysis. Noteworthy is the first-time reporting of canrenone in human hair. Anabolic agents were expected in hair, whereas undetectable compounds, such as peptide hormones and beta-2 agonists, were likely due to large molecular mass or high polarity. This study enhances understanding of hair analysis in doping investigations, providing insights into substance detectability.


Assuntos
Anabolizantes , Dopagem Esportivo , Animais , Humanos , Canrenona/análise , Dopagem Esportivo/métodos , Diuréticos/análise , Fezes/química , Cabelo/química , Detecção do Abuso de Substâncias/métodos
2.
BMC Infect Dis ; 22(1): 427, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35509007

RESUMO

BACKGROUND: Measles vaccination was introduced in Taiwan in 1978, and the disease was declared eliminated in Taiwan in 2007. However, new cases have been reported unpredictably since then. Hospital medical staff are at particularly high risk for measles. We evaluated the immunity status of hospital medical staff after changes in national and local hospital vaccination policies. METHODS: This retrospective study was conducted in a tertiary care medical center from January 2008 to June 2018. Data were retrieved from all healthcare workers receiving employment medical examinations. Those with a full medical record including the geometrical mean titer (GMT) of anti-measles IgG were included. Age and sex differences in the GMT were analyzed by Student's t-tests and Chi-squared tests. Univariate and multivariate logistic regression analysis were used to determine the odds of immunity. RESULTS: The IgG positive rate increased with age group (p < 0.001). Seropositive rates for the birth before 1977 and after 1978 groups were 94.8% and 70.2% (p < 0.001). The odds ratio was also significantly different between both cohorts (1.000 vs. 0.423, p = 0.002). Staff in the examination department showed the lowest positive percentage of 70.3% (95% CI: 66.9-73.7%), whereas staff in preventive and long-term care services disclosed the highest positive percentage of 83.2% (95% CI: 76.1-90.2%). Subgroups 2015, 2017, and 2018 (p = 0.046, 0.046, 0.049), after the vaccination booster policy was launched, showed significant increases in seropositivity. CONCLUSIONS: Immunity efficacy is better in birth groups before 1977, which was highly related to natural infection before national policy launched. The policy of vaccination is an effective method, but medical staff attains inadequate protective antibody levels for maintenance of herd immunity. A pre-employment policy of screening a third booster vaccine of measles (or MMR) is recommended to lower the incidence of disease spreading and avoid outbreaks.


Assuntos
Sarampo , Anticorpos Antivirais , Feminino , Humanos , Imunoglobulina G , Masculino , Sarampo/epidemiologia , Sarampo/prevenção & controle , Vacina contra Sarampo , Vacina contra Sarampo-Caxumba-Rubéola , Corpo Clínico , Políticas , Estudos Retrospectivos , Estudos Soroepidemiológicos , Centros de Atenção Terciária , Vacinação
3.
Asia Pac J Public Health ; 33(4): 411-417, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33715458

RESUMO

Postpartum depression (PPD) is a highly prevalent disorder characterized by increased vulnerability to morbidity and mortality. This study explores the predictors and prevalence of PPD among Taiwanese women. A total of 914 postpartum women was recruited from a mother-child-friendly hospital. These participants completed self-report questionnaires at 1 month postpartum, and their medical records were also examined for relevant information. Multivariate analyses were used to identify independent predictors of PPD. At 1 month postpartum, 18.8% had developed PPD. Multivariate analysis showed that the odds ratios for PPD were significantly lower among women who were breastfeeding, had more family support, and attended a postpartum care center, while those who were younger, primiparous, and who experienced gestational complications had a higher prevalence of PPD. Meanwhile, structural equation modeling showed that family support from partners, parents, and parents-in-law diminished depression scores through direct effects.


Assuntos
Depressão Pós-Parto , Depressão Pós-Parto/epidemiologia , Feminino , Hospitais/estatística & dados numéricos , Humanos , Prevalência , Fatores de Risco , Taiwan/epidemiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-31546692

RESUMO

BACKGROUND: Varicella seroprevalence in healthcare workers at a tertiary care hospital in Taiwan was assessed following the inclusion of varicella zoster vaccination in the national vaccination schedule in 2004 and was made a hospital policy in 2008. METHODS: Seroprevalence data were extracted from records of pre-employment health check-ups performed between 2008 and 2018 at a single medical center. Staff with complete medical records and anti-varicella zoster virus immunoglobulin G (VZV IgG) titers were included. Sex and age group differences in terms of geometric mean titer (GMT) were compared using analysis of variance and chi-squared tests. The significance of the correlation between age and the anti-VZV IgG titer was tested by linear regression. The odds of significant associations among age, sex, vocation, and the years of national and hospital adoption of vaccination were determined using univariate and multivariate analyses. p < 0.05 was considered statistically significant. RESULTS: Of the 7314 eligible participants, 5625 (76.90%) were women, and the mean patient age was 26.80 ± 8.00 years. The lowest VZV-positivity rates were in 18-20-year-old women (85.16%; GMT, 362.89 mIU/mL) and men (87.59%; GMT, 288.07 mIU/mL). VZV positivity increased with age (p < 0.001). Participants born before 2002 were more likely to be seropositive than those born after 2003 (odds ratio, 2.51 vs. 1.0; p < 0.001). The lowest seropositive rate was found in the nursing staff (88.91%; 95% confidence interval, 87.74%-90.05%). Varicella vaccine boosters have been required at pre-employment health check-ups since 2008 if anti-VZV antibodies were not detectable. A follow-up evaluation found marginal significant differences in the odds ratios of seropositivity after 2007 (p = 0.052), especially in 2008 and 2014 (p < 0.05) after the hospital policy launched. CONCLUSIONS: Despite public health efforts, a small number of healthcare workers were inadequately protected, and antibody titers were lower than required to maintain herd immunity. For effective prevention of nosocomial infection, VZV IgG status should be documented for all HCWs, and susceptible HCWs should be vaccinated to avoid outbreaks. Pre-employment screening and vaccination have increased immunity and need to be conducted to ensure protection of vulnerable patients.


Assuntos
Varicela/epidemiologia , Pessoal de Saúde/estatística & dados numéricos , Centros de Atenção Terciária , Vacinação/legislação & jurisprudência , Adulto , Idoso , Vacina contra Varicela , Feminino , Política de Saúde , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Prevalência , Estudos Soroepidemiológicos , Taiwan/epidemiologia , Adulto Jovem
5.
Small ; 14(22): e1704052, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29707890

RESUMO

Phase-engineered type-II metal-selenide heterostructures are demonstrated by directly selenizing indium-tin oxide to form multimetal selenides in a single step. The utilization of a plasma system to assist the selenization facilitates a low-temperature process, which results in large-area films with high uniformity. Compared to single-metal-selenide-based photodetectors, the multimetal-selenide photodetectors exhibit obviously improved performance, which can be attributed to the Schottky contact at the interface for tuning the carrier transport, as well as the type-II heterostructure that is beneficial for the separation of the electron-hole pairs. The multimetal-selenide photodetectors exhibit a response to light over a broad spectrum from UV to visible light with a high responsivity of 0.8 A W-1 and an on/off current ratio of up to 102 . Interestingly, all-transparent photodetectors are successfully produced in this work. Moreover, the possibility of fabricating devices on flexible substrates is also demonstrated with sustainable performance, high strain tolerance, and high durability during bending tests.

6.
Obes Facts ; 11(1): 37-45, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29402791

RESUMO

OBJECTIVE: Excess postpartum weight retention (PPWR) is related to long-term weight gain. Therefore, this study was conducted to identify the risk factors for PPWR to provide guidance for preventive strategies. METHODS: This cohort study surveyed 461 women who gave birth at a medical center between March 2014 and March 2016. The participants completed a questionnaire within 1 month of delivery, and their 6-month postpartum weight was tracked. RESULTS: The results showed that the mean pre-pregnancy BMI was 21.4 ± 3.3 kg/m2, and the mean gestational weight gain (GWG) was 12.8 ± 4.1 kg. The mean PPWR was 4.6 ± 3.5 kg at 1 month and 2.1 ± 3.3 kg at 6 months. Multivariate analysis revealed that GWG (adjusted OR: 1.92 (1.70-2.17)), pre-pregnancy BMI (adjusted OR: 0.85 (0.77-0.94)), and exclusive breastfeeding (adjusted OR: 0.55 (0.32-0.94)) were significantly correlated with a 1-month PPWR higher than the median value. In addition, GWG (adjusted OR: 1.30 (1.22-1.39)) and exclusive breastfeeding (adjusted OR: 0.37 (0.24-0.58)) were significantly correlated with a 6-month PPWR higher than the median value. CONCLUSION: Our findings indicate that the key to reducing PPWR is to control GWG and engage in exclusive breastfeeding.


Assuntos
Ganho de Peso na Gestação/fisiologia , Período Pós-Parto , Aumento de Peso/fisiologia , Adulto , Povo Asiático/estatística & dados numéricos , Índice de Massa Corporal , Aleitamento Materno/estatística & dados numéricos , Cesárea/estatística & dados numéricos , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade/etiologia , Sobrepeso/epidemiologia , Sobrepeso/etiologia , Gravidez , Complicações na Gravidez/epidemiologia , Fatores de Risco , Taiwan/epidemiologia , Magreza/epidemiologia , Magreza/etiologia , Adulto Jovem
7.
ACS Appl Mater Interfaces ; 10(11): 9645-9652, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29309121

RESUMO

Direct reduction of metal oxides into a few transition metal dichalcogenide (TMDCs) monolayers has been recently explored as an alternative method for large area and uniform deposition. However, not many studies have addressed the characteristics and requirement of the metal oxides into TMDCs by the selenization/sulfurization processes, yielding a wide range of outstanding properties to poor electrical characteristics with nonuniform films. The large difference implies that the process is yet not fully understood. In particular, the selenization/sulfurization at low temperature leads to poor crystallinity films with poor electrical performance, hindering its practical development. A common approach to improve the quality of the selenized/sulfurized films is by further increasing the process temperature, thus requiring additional transfer in order to explore the electrical properties. Here, we show that by finely tuning the quality of the predeposited oxide the selenization/sulfurization temperature can be largely decreased, avoiding major substrate damage and allowing direct device fabrication. The direct relationship between the role of selecting different metal oxides prepared by e-beam evaporation and reactive sputtering and their oxygen deficiency/vacancy leading to quality influence of TMDCs was investigated in detail. Because of its outstanding physical properties, the formation of tungsten diselenide (WSe2) from the reduction of tungsten oxide (WO x) was chosen as a model for proof of concept. By optimizing the process parameters and the selection of metal oxides, layered WSe2 films with controlled atomic thickness can be demonstrated. Interestingly, the domain size and electrical properties of the layered WSe2 films are highly affected by the quality of the metal oxides, for which the layered WSe2 film with small domains exhibits a metallic behavior and the layered WSe2 films with larger domains provides clear semiconducting behavior. Finally, an 8'' wafer scale-layered WSe2 film was demonstrated, giving a step forward in the development of 2D TMDC electronics in the industry.

8.
J Colloid Interface Sci ; 446: 352-8, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25576198

RESUMO

Titanium dioxide (TiO2)/ activated carbon (AC) composite materials, as capacitive deionization electrodes, were prepared by a two-step microwave-assisted ionothermal synthesis method. The electrosorption capacity of the composite electrodes was studied and the effects of AC characteristics were explored. These effects were investigated by multiple analytical techniques, including X-ray photoelectron spectroscopy, thermogravimetry analysis and electrochemical impedance spectroscopy, etc. The experimental results indicated that the electrosorption capacity of the TiO2/AC composite electrode is dependent on the characteristics of AC including the pore structure and the surface property. An enhancement in electrosorption capacity was observed for the TiO2/AC composite electrode prepared from the AC with higher mesopore content and less hydrophilic surface. This enhancement is due to the deposition of anatase TiO2 with suitable amount of Ti-OH. On the other hand, a decline in electrosorption capacity was observed for the TiO2/AC composite electrode prepared from the AC with higher micropore content and highly hydrophilic surface. High content of hydrogen bond complex formed between the functional group on hydrophilic surface with H2O, which will slow down the TiO2 precursor-H2O reaction. In such situation, the effect of TiO2 becomes unfavorable as the loading amount of TiO2 is less and the micropore can also be blocked.

9.
Nanotechnology ; 19(4): 045604, 2008 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-21817510

RESUMO

This study investigates the microstructures of multi-walled carbon nanotubes (MWNTs)/TiO(2) nanocomposites, obtained by sol-gel and hydrothermal processes. The synthesized nanocomposite materials were characterized by x-ray diffractometry (XRD), Brunauer-Emmett-Teller (BET) adsorption analysis, transmittance electron microscopy (TEM), scanning electron microscopy (SEM), photoluminescence (PL) spectroscopy, and x-ray photoelectron spectroscopy (XPS). The effects of the synthetic procedures and MWNTs on the morphology and photocatalytic activity of the nanocomposites were studied. The photocatalytic activity of the MWNTs/TiO(2) nanocomposite was elucidated based on the photooxidation of NO(x) under UV light illumination. A fleck-like and well dispersed TiO(2) microstructure on the surface of the MWNTs was observed in the sol-gel system, while compact and large aggregated particles were found in the hydrothermal procedure. The nanocomposite prepared by the sol-gel system exhibits better photocatalytic activity for NO oxidation (from 20.52 to 32.14%) than that prepared by the hydrothermal method (from 22.58 to 26.51%) with the same MWNT loading (from 0 to 8 wt%), respectively. The optimal MWNT content in the nanocomposite was considered at 8 wt%. Additionally, results confirm that the introduction of MWNTs will cause the NO(2) to be more consumed than NO in the photocatalytic experiments, leading to more complete NO(x) photooxidation. These observations indicate that the different TiO(2) distributions on the MWNT surfaces and MWNT contents in the materials would determine the morphology, the physicochemical and photocatalytic characteristics for the nanocomposite materials.

10.
Nanotechnology ; 19(37): 375305, 2008 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-21832549

RESUMO

This study fabricates dye-sensitized solar cells (DSSCs) based on TiO(2)/multi-walled carbon nanotube (MWCNT) nanocomposite photoanodes obtained by the modified acid-catalyzed sol-gel procedure. Results show that incorporating MWCNTs into a TiO(2)-based electrode efficiently improves the physicochemical properties of the solar cell. The results of dye adsorption and cell performance measurements indicate that introducing MWCNTs would improve the roughness factor (from 834 to 1267) of the electrode and the charge recombination of electron/hole (e(-)/h(+)) pairs. These significant changes could lead to higher adsorbed dye quantities, photocurrent and DSSC cell performance. Nevertheless, a higher loading of MWCNTs causes light-harvesting competition that affects the light adsorption of the dye-sensitizer, and consequently reduces the cell efficiency. This study suggests an optimum MWCNT loading in the electrode of 0.3 wt%, and proposes a sol-gel synthesis procedure as a promising method of preparing the TiO(2)-based nanocomposite.

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