Psychometric properties of the Social Cognitive Theory questionnaire for physical activity in a sample of Iranian adolescent girl students.

This research examined the validity and reliability of a researcher-developed questionnaire based on Social Cognitive Theory (SCT) to assess the physical activity behaviour of Iranian adolescent girls (SCT-PAIAGS). Psychometric properties of the SCT-PAIAGS were assessed by determining its face validity, content and construct validity as well as its reliability. In order to evaluate factor structure, cross-sectional research was conducted on 400 high-school girls in Tehran. Content validity index, content validity ratio and impact score for the SCT-PAIAGS varied between 0.97-1, 0.91-1 and 4.6-4.9 respectively. Confirmatory factor analysis approved a six-factor structure comprising self-efficacy, self-regulation, family support, friend support, outcome expectancy and self-efficacy to overcoming impediments. Factor loadings, t-values and fit indices showed that the SCT model was fitted to the data. Cronbach's α-coefficient ranged from 0.78 to 0.85 and intraclass correlation coefficient from 0.73 to 0.90.

Psychometric properties of the Social Cognitive Theory questionnaire for physical activity in a sample of Iranian adolescent girl students

This research examined the validity and reliability of a researcher-developed questionnaire based on Social Cognitive Theory [SCT] to assess the physical activity behaviour of Iranian adolescent girls [SCT-PAIAGS]. Psychometric properties of the SCT-PAIAGS were assessed by determining its face validity, content and construct validity as well as its reliability. In order to evaluate factor structure, cross-sectional research was conducted on 400 high-school girls in Tehran. Content validity index, content validity ratio and impact score for the SCT-PAIAGS varied between 0.97-1, 0.91-1 and 4.6-4.9 respectively. Confirmatory factor analysis approved a six-factor structure comprising self-efficacy, self-regulation, family support, friend support, outcome expectancy and self-efficacy to overcoming impediments. Factor loadings, t-values and fit indices showed that the SCT model was fitted to the data. Cronbach's alpha-coefficient ranged from 0.78 to 0.85 and intraclass correlation coefficient from 0.73 to 0.90

La présente étude visait à examiner la validité et la fiabilité d'un questionnaire mis au point par des chercheurs, basé sur la TSC, et visant à évaluer le comportement de jeunes adolescentes iraniennes en matière d'activité physique. Les propriétés psychométriques du questionnaire de TSC pour l'activité physique dans un échantillon de jeunes élèves filles iraniennes ont été évaluées en déterminant sa validité apparente, sa validité de contenu et de construit, ainsi que sa fiabilité. Afin d'évaluer la structure factorielle du questionnaire, une étude transversale a été conduite auprès de 400 lycéennes à Téhéran. L'index et le radio de validité de contenu, ainsi que le score d'impact du questionnaire de TSC pour l'activité physique dans un échantillon de jeunes élèves filles iraniennes, variaient de 0,97 à 1, de 0,91 à 1 et de 4,6 à 4,9 respectivement. L'analyse factorielle confirmatoire a validé une structure factorielle comprenant 6 aspects : l'auto-efficacité, l'auto-régulation, le soutien familial, le soutien social, l'attente du résultat et l'auto-efficacité pour dépasser les obstacles. La saturation factorielle, les valeurs de t et les indices d'ajustement ont montré que le modèle d'évaluation de la TSC était adapté aux données. Le coefficient alpha de Cronbach était compris entre 0,78 et 0,85 et le coefficient de corrélation intraclasse entre 0,73 et 0,90

Gd3+-DTPA-bis (N-methylamine) - anionic linear globular Dendrimer-G1; a more efficient MRI contrast media.

By advancing of molecular imaging techniques, magnetic resonance imaging (MRI) is becoming an increasingly important tool in early diagnosis. Researchers have found new ways to increase contrast of MRI images.Therefore some types of drug known as contrast media are produced. Contrast media improve the visibility of internal body structures in MRI images. Gadodiamide (Omniscan®) is one of these contrast media which is produced commercially and used clinically. In this study Gadodiamide was first synthesized and then qualitative and quantitative methods were carried out to ensure the proper synthesis of this drug then to increase the efficiency of this contrast medium use dendrimer that is one kind of nano particle. This dendrimer has a polyethylene glycol (PEG) core and citric acid branches. After dendrimer attached to Gadodiamide to ensure the proper efficient connection between them the stability studies were carried out and cytotoxicity of the drug was evaluated. Finally, after ensuring the non-toxicity of the drug, in vivo studies (injected into mice) MR imaging was performed to examine the impact of synthesis drug on the resolution of image.The result obtained from this study demonstrated that the attachment of Gadodiamide to dendrimer reduces its cytotoxicity and also improved resolution of image. Also the new contrast media (Gd3+-DTPA- bis [N-methylamine] - Dendrimer) - unlike Omniscan® - is biodegradable and able to enter the HEPG2 cell line. The results confirm the hypothesis that using dendrimer to synthesize this new nano contrast medium increases its effectiveness.

A comparative study of two novel nanosized radiolabeled analogues of methionine for SPECT tumor imaging.

It has been reported that most tumor cells show an increased uptake of variety of amino acids specially methionine when compared with normal cells and amino acid transport is generally increased in malignant transformation. Based on the evidences, two novel nanosized analogues of methionine (Anionic Linear Globular Dendrimer G(2), a biodigredabale anionic linear globular-Methionin, and DTPA-Methionine(1) conjugates) were synthesized and labeled with (99m)Tc and used in tumor imaging/ therapy in vitro and in vivo. The results showed marked tumor SPECT molecular imaging liabilities for both compounds but with a better performance by administration of (99m)Tc-Dendrimer G(2)-Methionin. The results also showed a good anticancer activity for 99mTc-DTPA-Methionine. Based on the present study (99m)Tc-Dendrimer G(2)-Methionin or 99mTc-DTPA-(Methionine)(1) have potentials to be used in tumor molecular imaging as well as cancer therapy in future.