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1.
Environ Sci Pollut Res Int ; 30(48): 105259-105274, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37713076

RESUMO

Environmental degradation is an urgent global concern. While previous studies acknowledge the substantial effects of both democracy and Information and Communication Technology (ICT) on environmental quality, their joint effects remain underexplored. Addressing this gap, our research investigates the individual and synergistic effects of democracy and ICT infrastructure on environmental quality. Utilizing the system generalized method of moments (GMM) estimator, we assess a panel dataset from 152 countries between 2003 and 2019. Our results indicate that both democracy and ICT infrastructure advancements substantially improve environmental quality. Furthermore, an enhanced ICT infrastructure augments the positive effects of democratic practices on the environment and vice versa. However, when ICT infrastructure is insufficient, the positive influence of democratic systems on the environment becomes negligible, and similarly, without a solid democratic foundation, the benefits of ICT infrastructure on environmental quality are diminished. This underscores a synergistic relationship between democracy and ICT in fostering sustainable environmental progress. Consequently, our study offers significant insights into the multifaceted interplay between democracy, ICT infrastructure, and the environment.


Assuntos
Dióxido de Carbono , Democracia , Dióxido de Carbono/química , Desenvolvimento Econômico , Comunicação , Tecnologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-34913854

RESUMO

Perchlorate is known as a thyroid disrupter. Its contamination in various tea samples was monitored, and 286 samples belonging to four types of tea leaves were analysed. The detection rate of perchlorate in tea was 99.3%. The mean concentration in different tea types decreased in order from green tea, oolong tea, white tea to black tea. A probabilistic approach was performed to evaluate the dietary exposure of perchlorate for six different subpopulations. The daily intakes (EDIs) for consumers over the age of 41 were higher than that of other subpopulations. The hazard quotient for six groups was lower than 1 even at the extreme percentile (P99). It indicates that the risk of dietary exposure to perchlorate from tea consumption for Fujian people is acceptable without considering other foodstuffs. However, the high occurrence of perchlorate in tea samples suggested that the actual source of this contaminant should be further investigated.


Assuntos
Exposição Dietética/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Folhas de Planta/química , Chá/química , Humanos , Método de Monte Carlo , Medição de Risco
3.
Anal Chim Acta ; 1088: 89-98, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31623720

RESUMO

The principle of chromatographic fingerprint is that certain diagnostic metabolites should be always distributed in a given plant and currently, it has been widely accepted as a promising means for medicinal plant authentication. Moreover, the chemical profile is the only evidence to clarify the ingredients of those consumable plant products, e.g. traditional Chinese medicine (TCM) prescriptions. Herein, efforts were made to describe the diagnostic metabolome of medicinal plant or TCM prescription using a binary code sequence. Forty-five well-known medicinal plants along with six relevant prescriptions were employed for concept illustration and proof. Each plant was subjected to chemical characterization, and diagnostic metabolites of all plants were gathered into a chemical pool containing 595 compounds. A robust method enabling the detection of all 595 constituents was then developed using LC coupled to scheduled multiple reaction monitoring. Analyst™ software was responsible for automatically judging the presence (defined as "1") or absence (defined as "0") of each analyte with a defined signal-to-noise threshold (S/N > 100). After converting each medicinal plant to a binary sequence consisting of 595 codes, an in-house database was built by involving all sequences. The potentials of sequence library retrieval towards plant authentication, preliminary chemical characterization, and deformulation of TCM prescriptions were demonstrated after that the diagnostic metabolome of each test sample was translated to a binary code sequence. Above all, binary code is a flexible tool for diagnostic metabolite sequencing of medicinal plants, and it should be an alternative tool of DNA barcoding towards plant authentication.


Assuntos
Metabolômica/métodos , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Métodos Analíticos de Preparação de Amostras , Composição de Medicamentos , Prescrições de Medicamentos , Fraude/prevenção & controle , Limite de Detecção , Medicina Tradicional Chinesa
4.
Inhal Toxicol ; 31(7): 259-273, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31556766

RESUMO

Sale of electronic cigarette (e-cigarette) products has exponentially increased in the past decade, which raise concerns about its safety. This updated review provides the available toxicology profile of e-cigarettes, summarizing evidence from in vitro and in vivo studies. Data regarding which components in e-liquids exhibit potential toxicities are inconsistent. Some studies have reported that nicotine plays a significant role in inducing adverse outcomes and that solvents alone do not induce any adverse effects. However, other studies have suggested that nicotine is not associated with any adverse outcomes, whereas solvents and flavorings are the key components to elicit considerable deleterious effects on cells or animals. In addition, most of the studies that have compared the toxicity of e-cigarettes with tobacco cigarettes have suggested that e-cigarettes are less toxic than tobacco cigarettes. Nevertheless, scientific evidence regarding the toxicity profile of e-cigarette is insufficient owing to the lack of a standardized research approach. In the future, scientific toxicology data derived from standardized testing protocols including nicotine, ingredients analysis, the various e-cigarette devices made from different materials are urgently needed for thorough toxicology assessment. This review aims to update the toxicity profiles, identify knowledge gaps, and outline future directions for e-cigarettes research, which would greatly benefit public health professionals.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Nicotina/toxicidade , Aerossóis , Humanos , Nicotina/análise , Medição de Risco , Estados Unidos
5.
Sci Total Environ ; 662: 218-226, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30690356

RESUMO

Rainwater samples from Shenzhen in south China were collected over the period of a year, and the chemical compositions were measured with the main purpose of understanding the acidification of rainwater and the controlling factors. The pH value of precipitation ranged from 3.72 to 6.77, with a volume-weighted mean (VWM) value of 4.29, and the acid rain frequency was 97%. The VWM concentrations of anions and cations followed the order of SO42- > Cl- > NO3- and Na+ > Ca2+ > NH4+ > Mg2+ > K+, respectively. Air mass back-trajectory and positive matrix factorization analyses indicated that sources of ions in rainwater were mainly from sea salt, soil dust and anthropogenic activities. Compared with other areas in China, the rainwater of Shenzhen has the lowest values of the NP/AP, ∆pH and NF values of Ca2+ and NH4+, indicating that the lack of the capacity for neutralization could be the main reason for the severe acid rain problem. It is noteworthy that the rain acidification tendency is obvious, and the pH value has reduced by 1.0 units since the 1980s. Based on a comparison of the chemical compositions of the rainwater from different historical periods, the NO3- concentration was found to have increased consistently, whereas the NH4+ concentration maintained a decreasing trend since 1980. On the other hand, the nss-SO42- and nss-Ca2+ concentrations increased after 1980 and then decreased after 1994. Meanwhile, the decreasing pH was accompanied by a decreasing NP/AP ratio. These results suggest that the changes in human activities at different stages of urban development can lead to a synergistic change in the chemical characteristics of precipitation. Both an increase in the acidic species emissions (especially NOX) due to rapid economic development and a decrease in the alkaline ions concentration due to urbanization have resulted in the rain acidification tendency in Shenzhen.

6.
J Chromatogr A ; 1558: 37-49, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-29773341

RESUMO

The quality of herbal medicines (HMs) is the prerequisite for their pronounced therapeutic outcomes in clinic, and multi-component (also known as quality markers, Q-markers) quantification has been widely emphasized as a viable means for quality evaluation. Because of the chemical diversity, the quality control practices are extensively dampened by four principal technical bottlenecks, including the lack of authentic compounds, large polarity span, extensive concentration range, and signal misrecognition for those potential Q-markers. An attempt to promote the potential of LC-MS/MS is made herein to cope with those obstacles and Chinese agarwood was employed as a case study. Firstly, a home-made fraction collector was introduced to automatically fragment the entire extract into a panel of fractions-of-interest. Secondly, quantitative 1H-NMR was deployed to offset the LC-MS/MS potential towards in-depth chemical profiling each fraction, and those well-defined fractions were then pooled and combined with some accessible authentic compounds to generate the pseudo-mixed standard solution. Thirdly, serial improvements were conducted for LC-MS/MS measurements. Reversed phase LC and hydrophilic interaction LC were serially coupled in respond to the large polarity window, and online parameter optimization, response tailoring, as well as RRCEC (relative response vs. collision energy curve) matching were integrated in MS/MS domain to advance the quantitative confidences. Simultaneous determination was conducted for 26 components, in total, in Chinese agarwood after method validation. In particular, authentic compound-free quantification was achieved for eight 2-(2-phenylethyl)chromone derivatives. Above all, the strategy is a promising solution to completely tackle with the technical barriers toward Q-marker quantification-oriented quality control of Chinese agarwood, as well as other HMs.


Assuntos
Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/normas , Medicina Herbária , Cromatografia Líquida , Cromatografia de Fase Reversa , Análise por Conglomerados , Medicamentos de Ervas Chinesas/química , Interações Hidrofóbicas e Hidrofílicas , Sistemas On-Line , Espectroscopia de Prótons por Ressonância Magnética , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Soluções , Espectrometria de Massas em Tandem , Fatores de Tempo
7.
Anal Chim Acta ; 886: 98-106, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26320641

RESUMO

Binding affinity of a small molecule drug candidate to a therapeutically relevant biomolecular target is regarded the first determinant of the candidate's efficacy. Although the ultrafiltration-LC/MS (UF-LC/MS) assay enables efficient ligand discovery for a specific target from a mixed pool of compounds, most previous analysis allowed for relative affinity ranking of different ligands. Moreover, the reliability of affinity measurement for multiple ligands with UF-LC/MS has hardly been strictly evaluated. In this study, we examined the accuracy of K(d) determination through UF-LC/MS by comparison with classical ITC measurement. A single-point K(d) calculation method was found to be suitable for affinity measurement of multiple ligands bound to the same target when binding competition is minimized. A second workflow based on analysis of the unbound fraction of compounds was then developed, which simplified sample preparation as well as warranted reliable ligand discovery. The new workflow implemented in a fragment mixture screen afforded rapid and sensitive detection of low-affinity ligands selectively bound to the RNA polymerase NS5B of hepatitis C virus. More importantly, ligand identification and affinity measurement for mixture-based fragment screens by UF-LC/MS were in good accordance with single ligand evaluation by conventional SPR analysis. This new approach is expected to become a valuable addition to the arsenal of high-throughput screening techniques for fragment-based drug discovery.


Assuntos
Antivirais/química , Antivirais/farmacologia , Descoberta de Drogas/métodos , Hepacivirus/metabolismo , Hepatite C/virologia , Proteínas não Estruturais Virais/metabolismo , Cromatografia Líquida/economia , Cromatografia Líquida/métodos , Descoberta de Drogas/economia , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Ensaios de Triagem em Larga Escala/economia , Ensaios de Triagem em Larga Escala/métodos , Humanos , Ligantes , Espectrometria de Massas/economia , Espectrometria de Massas/métodos , Ligação Proteica , Reprodutibilidade dos Testes , Ultrafiltração/economia , Ultrafiltração/métodos , Fluxo de Trabalho
8.
Arch Gerontol Geriatr ; 50 Suppl 1: S30-3, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20171453

RESUMO

The purpose of this study was to evaluate the outcomes of elderly inpatients with geriatric syndromes. A prospective study involving patients aged 65 years and older in 12 community hospitals was performed. Baseline data, which included demographic characteristics, mini mental status exam, geriatric depression scale (GDS), mini nutritional assessment (MNA), activities of daily living (ADL), and instrumental activities of daily living (IADL), were collected in geriatric assessments. The primary outcome was functional deterioration; additional outcomes included mortality, re-hospitalization, and emergency department visits, as identified by telephone interview and chart review. A total of 1,008 patients were recruited: 31.2% of the participants were ADL intact, 21.3% were IADL-intact, 11.5% had depression, 29.3% had nutritional problems, and 60.3% had impaired cognition at baseline. During follow-up, 172 patients (19.3%) died, 43.8% reported ADL deterioration, and 45.9% reported IADL deterioration. On multivariate analysis, older age, low mini mental state examination (MMSE) score, and low MNA score were predictors of functional deterioration. Under the interdisciplinary team care of the Community Hospital Reform Plan (CHRP), most of the elderly patients maintained or increased their functional capacity; the one-year mortality rate was higher than that of the general population but lower than that of other studies targeting the frail elderly.


Assuntos
Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/terapia , Serviços de Saúde Comunitária/organização & administração , Reforma dos Serviços de Saúde , Serviços de Saúde para Idosos/organização & administração , Nível de Saúde , Hospitalização/estatística & dados numéricos , Atividades Cotidianas , Idoso , Transtornos Cognitivos/diagnóstico , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , Índice de Gravidade de Doença , Síndrome , Taiwan/epidemiologia
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