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1.
J Fluoresc ; 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37646875

RESUMO

2-Pyrazoline containing benzothiazole ring 2-[1-(1,3-benzothiazol-2-yl)-5-(4-methoxyphenyl)-4,5-dihydro-1H-pyrazol-3-yl]phenol (BP) have been synthesized for the effective identification of picric acid over other competing nitro compounds using fluorescence technique. The pyrazoline BP showed quenching efficiency as high as 82% comparative to other nitro aromatics. The limit of detection and limit of quantification were found to be 1.1 µM and 3.3 µM. The possible mechanism with the quenched PA detection efficiency was based on fluorescence energy transfer and photoinduced electron transfer. Moreover, the observed results were supported by the optimized structures of the compounds using the DFT/B3LYP/6-311G/LanL2DZ method. Eventually, the pyrazoline derivative BP was further utilized for natural water samples, showing recoveries in the 87.62-101.09% and RSD was less than 3%.

2.
J Fluoresc ; 32(3): 969-981, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35230566

RESUMO

A simple fluorescent chemosensor 5-(4-methylphenyl)-3-(5-methylfuran-2-yl)-1-phenyl-4, 5-dihydro-1H-pyrazole (PY) has been synthesized for the detection of Cd2+ ion.The fluorescent probe PY shows high selectivity for Cd2+in the presence of othermetal ions (Co2+, Cu2+, Hg2+, Mn2+, Zn2+, Fe3+, Pb2+, Ni2+, and Al3+). The fluorescence intensity of the PY has been strongly quenched with increasing concentration of Cd2+ (0-0.9 µM)via photoinduced electron transfer mechanism. The binding constant of Cd2+ to PY for the 1:1 complex isfound to be 5.3 × 105 M-1with a detection limit of 0.09 µM. The chemosensor was successfully applied for determination of Cd2+ in different water samples (tap, river, and bottled water) showing good recovery values in the range of 94.8-101.7% with RSD less than 3%. Density functional theory (DFT) calculations were also performed to investigate electronic and spectral characteristics which are quite agreeable with the experimental value. The results show that the synthesized fluorescent chemosensor shows good selectivity towards Cd2+ and can be readily applied for the detection of Cd2+ in real samples including water samples.


Assuntos
Cádmio , Água Potável , Corantes Fluorescentes , Íons , Modelos Teóricos , Pirazóis , Espectrometria de Fluorescência/métodos
3.
J Fluoresc ; 32(1): 359-367, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34851472

RESUMO

A simple synchronous fluorescent chemosensor 3-hydroxy-2-(4-methoxyphenyl)-4H-chromen-4-one (3-HC) has been synthesized for the selective analysis of Al3+. On the addition of Al3+, 3-HC displayed a redshift with a change in wavelength of emission maximum from 436 to 465 nm along with enhancement in fluorescence intensity, which formed the basis for its sensitive detection. Under optimized conditions, 3-HC was applied for the determination of Al3+ in the concentration range of 1 × 10-7-1 × 10-6 M. The limit of detection (LOD) and limit of quantification (LOQ) values were found out to be 1.69 × 10-8 and 5.07 × 10-8 M respectively. Further, the developed method was applied for the analysis of Al3+ in real water samples (tap water, bottled water, and tube well water) which showed good recovery values in the range of 95-99.7% with RSD less than 4%.

4.
J Fluoresc ; 32(6): 2319-2331, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36131167

RESUMO

A simple pyrazoline-based ''turn off'' fluorescent sensor 5-(4-methoxyphenyl)-3-(5-methylfuran-2-yl)-1-phenyl-4,5-dihydro-1H-pyrazole (PFM) was synthesized and well characterized by different techniques such as FT-IR, 1H-NMR, 13C-NMR, and mass spectrometry. The synthesized sensor PFM was utilized for the detection of Fe3+ ions. Fluorescence emission selectively quenched by Fe3+ ions compared to other metal ions (Mn2+, Al3+, Fe2+, Hg2+, Cu2+, Co2+, Ni2+, Cd2+, Pb2+, and Zn2+) via paramagnetic fluorescence quenching and showed good anti-interference ability over the existence of other tested metals. Under optimum conditions, the fluorescence intensity of sensor quenched by Fe3+ in the range of 0 to 3 µM with detection limit of 0.12 µM. Binding of Fe3+ ions to PFM solution were studied by fluorescent titration, revealed formation of 1:1 PFM-Fe metal complex and binding constant of complex was found to be of 1.3 × 105 M-1. Further, the fluorescent sensor has been potentially used for the detection of Fe3+ in environmental samples (river water, tap water, and sewage waste water) with satisfactory recovery values of 99-101%.


Assuntos
Ferro , Mercúrio , Ferro/análise , Espectrometria de Fluorescência , Corantes Fluorescentes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Esgotos , Águas Residuárias , Cádmio/análise , Chumbo/análise , Íons/análise , Mercúrio/análise , Pirazóis
5.
Assay Drug Dev Technol ; 18(1): 64-74, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31742429

RESUMO

The fruits of Trapa bispinosa (TB) and seeds of Trigonella foenum-graecum (TF) are used for their nutraceutical properties in various systems of traditional medicine practiced in India. In this study aqueous and methanolic extracts of TB fruits and TF seeds were prepared and their protective effect was studied on hydrogen peroxide (H2O2)-treated neuroblastoma (NB-41) cell line. Cell viability, nitric oxide (NO) levels, mRNA, and protein profiles were analyzed and compared with untreated control. Results show that aqueous extracts of both TB and TF provide significant protection to neuroblastoma cells with TF aqueous extract offering better protection through upregulation of neuronal nitric oxide synthase (nNOS) against hydrogen peroxide generated stress. This is the first report demonstrating protection of neuronal cell lines by use of TB and TF extracts through modulation of nNOS activity.


Assuntos
Antioxidantes/farmacologia , Lythraceae/química , Neuroblastoma/metabolismo , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico Sintase Tipo I/metabolismo , Extratos Vegetais/farmacologia , Trigonella/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Frutas/química , Humanos , Peróxido de Hidrogênio/antagonistas & inibidores , Neuroblastoma/induzido quimicamente , Neuroblastoma/patologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Sementes/química , Células Tumorais Cultivadas
6.
Environ Int ; 121(Pt 1): 461-470, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30273869

RESUMO

Multiple studies in India have found elevated blood lead levels (BLLs) in target populations. However the data have not yet been evaluated to understand population-wide exposure levels. We used arithmetic mean blood lead data published from 2010 to 2018 on Indian populations to calculate the average BLLs for multiple subgroups. We then calculated the attributable disease burden in IQ decrement and Disability Adjusted Life Years (DALYs). Our Pubmed search yielded 1066 articles. Of these, 31 studies representing the BLLs of 5472 people in 9 states met our study criteria. Evaluating these, we found a mean BLL of 6.86 µg/dL (95% CI: 4.38-9.35) in children and 7.52 µg/dL (95% CI: 5.28-9.76) in non-occupationally exposed adults. We calculated that these exposures resulted in 4.9 million DALYs (95% CI: 3.9-5.6) in the states we evaluated. Population-wide BLLs in India remain elevated despite regulatory action to eliminate leaded petrol, the most significant historical source. The estimated attributable disease burden is larger than previously calculated, particularly with regard to associated intellectual disability outcomes in children. Larger population-wide BLL studies are required to inform future calculations. Policy responses need to be developed to mitigate the worst exposures.


Assuntos
Efeitos Psicossociais da Doença , Exposição Ambiental , Poluentes Ambientais/sangue , Chumbo/sangue , Anos de Vida Ajustados por Qualidade de Vida , Pessoas com Deficiência/estatística & dados numéricos , Humanos , Índia
7.
Burns ; 32(1): 104-11, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16406370

RESUMO

From a prospective study on burn patients admitted at the Burn Center in Kuwait during 1993-2001, 826 paediatric burn cases, in 0-14 years age group, were retrieved to study incidence, causes, and mortality among children. The demographic characteristics, clinical features, and outcome constituted our data file in Statistical Software, SPSS. Overall incidence rate was 17.5/100,000 children aged 0-14 years, being almost twice (34/100,000) among those between 0 and 4 years, constituting 70.8% of all paediatric burns. Scald was the main cause of burn (67%), followed by flame (23%). Mean age (6.4 years) of children with flame burns, was significantly higher (p < 0.001) than those with scalds, or other causes. A positive significant correlation existed between duration of hospital stay and TBSA% (r = 0.56, p < 0.001). Overall mortality rate was 0.23/100,000 children, maximum (0.52/100,000) being in children below 5 years. Among 11 (1.3%) non-survivors, flame burns caused nine fatalities. Multiple logistic regression mooring predicted children aged < 5 years, flame burns and TBSA >or= 70%, (OR = 29.2, p < 0.001), as main contributing factors to fatal outcome among children. Gender and nationality had no influence on incidence or mortality. These findings will hopefully stimulate development of targeted and sustainable interventions for reducing burns occurrence among identified paediatric high-risk groups.


Assuntos
Queimaduras , Adolescente , Distribuição por Idade , Superfície Corporal , Queimaduras/epidemiologia , Queimaduras/etiologia , Queimaduras/mortalidade , Causas de Morte , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Kuweit/epidemiologia , Tempo de Internação , Masculino , Estudos Prospectivos , Fatores de Risco
8.
Burns ; 31(2): 188-92, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15683691

RESUMO

A prospective study was carried out on a total of 2111 burn patients admitted at the Burn Center in Kuwait, during 1993 to 2001, with the purpose of predicting the risk factors influencing the fatal outcome. A total of 111 (5.3%) patients died, giving an annual average of 12 deaths, and a mortality rate of 0.64/100,000 population. The data, from the in-patient records, included the most commonly available demographic features viz. age, gender and nationality, as well as best recorded clinical factors, such as cause of burn, total body surface area (TBSA), duration of hospital stay and outcome, for analysis. Kolmogorov-Smirnov z test showed the median age (30 years) and TBSA (80%) significantly higher (p < 0.001) among those died as compared to 24 years and 10%, respectively in patients survived. The Chi-square test revealed a fatal outcome associated with gender and cause of burn. The multiple logistic regression model predicted patients, aged 60 years and above (OR: 9.9, p < 0.001), female gender (OR: 2.2, p < 0.016), Flame burns (OR: 3.5, p < 0.035), and TBSA > 90% (OR: 23.5, p < 0.001), as the most influencing risk factors for a fatal outcome at this burn center. Patients with these characteristics need to be given special attention during in-patient care.


Assuntos
Queimaduras/mortalidade , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Queimaduras/etnologia , Queimaduras/etiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Kuweit/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Regressão , Fatores de Risco , Distribuição por Sexo
9.
Adv Mind Body Med ; 29(1): 18-25, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25607119

RESUMO

Yoga and breathing techniques have become increasingly popular in recent decades. Sudarshan Kriya (SK) is a type of rhythmic and controlled breathing that involves cyclic breathing in which long breaths are followed by medium and short breaths. Scientific research has been conducted to study the effects of SK on different physiological parameters. Various studies have shown that the technique is simple and cost effective and can be used as a complementary therapy, together with ongoing conventional treatments, to help people suffering from extreme levels of stress, anxiety, and other physical problems. Studies have demonstrated that SK can play an important role in promoting a healthy lifestyle by improving immunity, antioxidant status, hormonal status, and brain functioning. Through available scientific evidence and research, the current article aims to review the complementary role of rhythmic breathing (ie, SK) as a practical and effective tool to alleviate stress, improve health, and increase wellness.


Assuntos
Pressão Sanguínea/fisiologia , Exercícios Respiratórios , Sistema Imunitário/fisiologia , Estresse Fisiológico/fisiologia , Adulto , Ansiedade , Feminino , Hormônios/sangue , Humanos , Leucócitos/fisiologia , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Yoga , Adulto Jovem
10.
Environ Health Perspect ; 121(7): 791-6, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23649493

RESUMO

BACKGROUND: Prior calculations of the burden of disease from toxic exposures have not included estimates of the burden from toxic waste sites due to the absence of exposure data. OBJECTIVE: We developed a disability-adjusted life year (DALY)-based estimate of the disease burden attributable to toxic waste sites. We focused on three low- and middle-income countries (LMICs): India, Indonesia, and the Philippines. METHODS: Sites were identified through the Blacksmith Institute's Toxic Sites Identification Program, a global effort to identify waste sites in LMICs. At least one of eight toxic chemicals was sampled in environmental media at each site, and the population at risk estimated. By combining estimates of disease incidence from these exposures with population data, we calculated the DALYs attributable to exposures at each site. RESULTS: We estimated that in 2010, 8,629,750 persons were at risk of exposure to industrial pollutants at 373 toxic waste sites in the three countries, and that these exposures resulted in 828,722 DALYs, with a range of 814,934-1,557,121 DALYs, depending on the weighting factor used. This disease burden is comparable to estimated burdens for outdoor air pollution (1,448,612 DALYs) and malaria (725,000 DALYs) in these countries. Lead and hexavalent chromium collectively accounted for 99.2% of the total DALYs for the chemicals evaluated. CONCLUSIONS: Toxic waste sites are responsible for a significant burden of disease in LMICs. Although some factors, such as unidentified and unscreened sites, may cause our estimate to be an underestimate of the actual burden of disease, other factors, such as extrapolation of environmental sampling to the entire exposed population, may result in an overestimate of the burden of disease attributable to these sites. Toxic waste sites are a major, and heretofore underrecognized, global health problem.


Assuntos
Efeitos Psicossociais da Doença , Exposição Ambiental , Poluentes Ambientais/toxicidade , Locais de Resíduos Perigosos , Mortalidade , Anos de Vida Ajustados por Qualidade de Vida , Monitoramento Ambiental , Poluentes Ambientais/análise , Humanos , Índia/epidemiologia , Indonésia/epidemiologia , Filipinas/epidemiologia
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