مجله دانشگاه علوم پزشکی اراک
سال پانزدهم شماره 10 (پیاپی 69، اسفند 1391)

International AIDS questionnaire allows for making cross-cultural comparisons between individual’s levels of awareness and attitudes towards AIDS. This study assessed the reliability and validity of international AIDS questionnaire for Iranian student population.

In this cross-sectional study، 448 students studying in non-medical sciences at universities in Qom were selected through convenience sampling. The participants completed the international AIDS questionnaire–Persian version (IAQ-P). Confirmatory and explanatory factor analysis، Pearson correlation، and Cronbach''s Alpha were used in order to examine construct and concurrent validities، respectively. Independent t-test was run to compare the questionnaire scores between male and female participants.

The CFA supported the four-factor model، and the normative data showed patterns similar to previous research. Four dimensions of the questionnaire data were satisfactory (AGFI=0. 91، GFI=0. 93 and RMSEA=0. 04، P<0. 001). The total IAQ-P had a high internal consistency (Cronbach’s alpha=0. 80). Cronbach’s alphas for the sub-scales were 0. 78 (myths)، 0. 78 (attitudes)، 0. 79 (personal risk)، and 0. 60 (facts). After one month، test-retest study on a sub-sample of 41 students revealed Pearson correlation coefficient ranges from 0. 36 to 0. 75 (P<0. 001).

The IAQ-P was shown to be a valid and reliable instrument and the results of this study are similar to other versions of IAQ in other languages.

The importance of VP2 protein of canine parvovirus to bind to human cancer cells and to detect the virus in veterinary detection kits has motivated a lot of research on the production of this protein. In this project، a surface gene of canine parvovirus (VP2) was cloned and expressed in a prokaryotic vector system and its expression was optimized in a specific cell-free prokaryotic expression system.

In this experimental study، plasmid pET-21aVP2 was constructed by cloning the PCR product of VP2 gene of canine parvovirus into the plasmid expression pET-21a vector. The best sequence was analyzed through PCR and it was followed by confirmation with sequencing and restriction digestion. To produce VP2 protein، plasmid pET-21aVP2 was transferred into Escherichia coli، Rosetta (DE3) strain، and the expression of this protein was induced by IPTG. The production of VP2 protein in both systems was evaluated using SDS PAGE technique. The expressed protein was checked with monoclonal antibody against VP2 protein by Western blotting technique.

Successful cloning of VP2 protein was confirmed by enzymatic digestion and sequencing. The expression of VP2 protein in bacterial and cell-free prokaryotic systems was verified by SDS PAGE and the specific band in Western blotting also confirmed the VP2 protein.

The results of this study showed that VP2 gene was amplified in the cloning phases and it was successfully cloned in the expression vector. Protein expression was confirmed in both bacterial and cell-free prokaryotic systems.

Gastric cancer is the second leading cause of mortality due to cancer worldwide and it is the most common type of cancer in Iran. The aim of this study was to assess the effects of prognostic factors on the survival of patients with gastric cancer using the penalized spline in Cox model and compare it with Cox proportional hazards model.

In this retrospective study، information obtained from a total of 216 gastric cancer patients who underwent surgery at Taleghani Hospital of Tehran between 2003 and 2008 years was included. Cox proportional hazards model and penalized spline in Cox model were used. R software was used for data analysis. The efficacy of these models was compared according to Akaike information criterion.

The five-year survival rate was 30% and the mean follow-up time was 16. 60±15. 28 months. Survival mean and median were 46 and 30 months، respectively. The analysis of Cox proportional hazards and penalized spline models resulted in age at diagnosis and tumor size as prognostic factors for survival time (P<0. 05). Also، Akaike information criterion and survival curve for patients with a tumor size over 35 mm and age at diagnosis over 45 years were equal in both models.

Cox proportional hazards and penalized spline models generated similar results; thus، it is more appropriate to use Cox proportional hazards model because of its ease of interpretation and capability of modeling both continuous and discrete covariates. This study also showed if gastric cancer is diagnosed early، the relative risk of death will reduce.