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1.
Appl Biochem Biotechnol ; 176(2): 344-58, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25825248

RESUMO

In this research, TiO2/ZrO2 nanocomposite has been prepared using sol-gel method. The TiO2/ZrO2 composite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and transmission electron microscopy (TEM). A sensitive electrochemical biosensor is also presented for the determination of Taxol based on ds-DNA decorated multiwall carbon nanotubes-TiO2/ZrO2-chitosan-modified pencil electrode (ds-DNA-MWNTs-TiO2/ZrO2-CHIT-PGE). The UV spectroscopic data and differential pulse voltammetry revealed that there is a strong interaction between ds-DNA and Taxol. The groove binding of Taxol to ds-DNA helix has been characterized by a red shift (less than 8 nm) in wavelength and the decrease in the differential pulse voltammetry oxidation signal intensity of the Taxol at pencil graphite electrode (PGE) after its interaction with ds-DNA. Finally, a pretreated PGE modified with ds-DNA-MWNTs-TiO2/ZrO2-CHIT was tested in order to determine Taxol content in the solution. The dynamic range was from 0.7 to 1874.0 nmol L(-1) with a detection limit of 0.01 nmol L(-1). This sensing platform was successfully applied for the determination of Taxol in pharmaceutical and biological samples.


Assuntos
DNA/química , Técnicas Eletroquímicas , Paclitaxel/análise , Eletrodos , Sensibilidade e Especificidade
2.
Int J Occup Environ Med ; 5(2): 65-71, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24747996

RESUMO

BACKGROUND: Many workers suffer from low-back pain. Type and severity of spinal complaints have relationship with work load. Lack of adherence to ergonomics recommendations among the important causes of low-back pain. OBJECTIVE: To assess the effect of 3 ergonomics training programs on the prevalence of lowback pain among workers of an Iranian automobile factory. METHODS: In a parallel-design 4-arm randomized clinical trial, 760 active workers of an automobile factory were studied. 503 workers were found eligible and randomized into 3 intervention groups (n=252), and a control group (n=251). The intervention groups consisted of 3 arms: 84 workers were educated by pamphlet, 84 by lectures, and 84 by workshop. Nordic questionnaire was used to determine the prevalence of spinal complaint before and 1-year after the interventions. The trial is registered with the Iranian Randomized Clinical Trial Registry, number IRCT2013061213182N2. RESULTS: Out of 503 workers, 52 lost to follow-up leaving 451 workers for analyses. The prevalence of low-back pain at the baseline was not significantly different among the studied arms. 1-year after the interventions, the prevalence did not change significantly from the baseline values for the lecture and pamphlet group. However, the prevalence of LBP experienced during the last year significantly (p=0.036) decreased from 42% to 23% in participant took part in the workshop. CONCLUSION: Training of automobile factory workers in ergonomics is more effective by running workshop than giving lecture or disseminating pamphlet.


Assuntos
Ergonomia/métodos , Dor Lombar/prevenção & controle , Saúde Ocupacional/educação , Adulto , Automóveis , Ergonomia/normas , Humanos , Capacitação em Serviço/métodos , Irã (Geográfico)/epidemiologia , Dor Lombar/epidemiologia , Dor Lombar/etiologia , Prevalência , Inquéritos e Questionários
3.
Iran Red Crescent Med J ; 14(4): 198-203, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22754681

RESUMO

BACKGROUND: Musculoskeletal disorders in developing countries are considered as main cause of occupational disorders and disability and highly associated with socioeconomic burden to individual, organization and society in general view. The purpose of this study was to determine the prevalence of musculoskeletal disorders and associated risk factors among Iranian steel workers. METHODS: In a cross-sectional study, 1439 questionnaires were provided from 1984 randomly selected workers of four Iranian steel industries. Data of musculoskeletal disorders was gathered by means of standardized Nordic self-reporting questionnaire. Demographic and work related data were collected into the check list. RESULTS: Out of 1984 individuals, 1439 questionnaires returned and mean age of study workers was 37.23±8.74 years old. Among workers, 46.3% in the past week and 61% in the last year claimed one of musculoskeletal disorders in their bodies. Lumbar, knee(s) and neck areas had the most common musculoskeletal disorders. Musculoskeletal disorders had significant association with the job time of work and BMI. CONCLUSION: Musculoskeletal disorders in Iranian steel industries happened in high rate. Ergonomic interventions strategies into the workplaces must be focused to eliminate environmental hazards such as apposition on the time of work and manual handling of heavy loads.

4.
Acta Neurol Belg ; 112(2): 171-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22426673

RESUMO

The worldwide dramatic increase in mobile phone use has generated great concerns about the detrimental effects of microwave radiations emitted by these communication devices. Reaction time plays a critical role in performing tasks necessary to avoid hazards. As far as we know, this study is the first survey that reports decreased reaction time after exposure to electromagnetic fields generated by a high specific absorption rate mobile phone. It is also the first study in which previous history of mobile phone use is taken into account. The aim of this study was to assess both the acute and chronic effects of electromagnetic fields emitted by mobile phones on reaction time in university students. Visual reaction time (VRT) of young university students was recorded with a simple blind computer-assisted-VRT test, before and after a 10 min real/sham exposure to electromagnetic fields of mobile phones. Participants were 160 right-handed university students aged 18-31. To assess the effect of chronic exposures, the reaction time in sham-exposed phases were compared among low level, moderate and frequent users of mobile phones. The mean ± SD reaction time after real exposure and sham exposure were 286.78 ± 31.35 ms and 295.86 ± 32.17 ms (P < 0.001), respectively. The age of students did not significantly alter the reaction time either in talk or in standby mode. The reaction time either in talk or in standby mode was shorter in male students. The students' VRT was significantly affected by exposure to electromagnetic fields emitted by a mobile phone. It can be concluded that these exposures cause decreased reaction time, which may lead to a better response to different hazards. In this light, this phenomenon might decrease the chances of human errors and fatal accidents.


Assuntos
Telefone Celular , Campos Eletromagnéticos/efeitos adversos , Tempo de Reação/efeitos da radiação , Adulto , Fatores Etários , Desenho Assistido por Computador , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Fatores Sexuais , Fatores de Tempo , Adulto Jovem
6.
Anal Biochem ; 341(2): 259-66, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15907871

RESUMO

A new salicylate-selective electrode based on the complex of (2-[(E)-2-(4-nitrophenyl)hydrazono]-1-phenyl-2-(2-quinolyl)-1-ethanone) Cu(II) as the membrane carrier was developed. The electrode exhibited a good Nernstian slope of -59.6+/-1.0 mV/decade and a linear range of 1.0 x 10(-6) to 1.0M for salicylate. The limit of detection was 5.0 x 10(-7) M. The electrode had a fast response time of 10 s and can be used for more than 3 months. The selective coefficients were determined by the fixed interference method and could be used in the pH range of 4.0 to 10.5. The electrode was employed as an indicator electrode for direct determination of salicylate in pharmaceutical and biological samples.


Assuntos
Eletrodos , Hidrazonas/química , Compostos Organometálicos/química , Cloreto de Polivinila/química , Potenciometria/métodos , Ácido Salicílico/análise , Membranas Artificiais
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