مجله تحقیقات نظام سلامت
سال نهم شماره 3 (خرداد 1392)

Ghrelin، the only known appetite stimulating hormone in humans، may be one factor involved in increased appetite، cravings and food intake following weight loss. Innovative strategies for suppressing ghrelin and decreasing appetite during weight loss maintenance are needed. Knowledge about the relationship between exercise and appetite is important both for athletes wishing to optimize performance and for those interested in maintaining a healthy body weight. The purpose of the current review was to describe the current status of evidence about ghrelin and lifestyle factors and to discuss implications for obesity treatment.

This study was a narrative review in which papers of clinical trial designs were selected using data bases and scientific search engines such as PubMed and Elsevier with the keywords ghrelin، appetite، exercise، weight، and obesity. All the papers were published from 2000 to 2012.

Evidence suggested that chronic exercise training typically causes a partial compensation in energy intake perhaps due to changes in appetite regulating hormones. Many studies have demonstrated that acute exercise transiently suppresse appetite and this has been termed ‘exercise induced anorexia’. From a practical standpoint athletes should not feel concerned that exercise will cause overeating as there is limited evidence to support this.

For desiring weight loss there may be some merit in performing exercise in the postprandial period as a means of enhancing the satiating effect of a meal. Chronic exercise training typically causes a partial compensation in energy intake perhaps due to changes in ghrelin hormone. Additional evidence is required to confirm the effectiveness of this strategy.

Although، most of the experimental studies demonstrated that conjugated linoleic acid has effects on metabolic syndrome، but the number of human studies in this area are limited and the result of these studies are controversial. This systematic review was conducted to summarize the literature from clinical trials and experimental studies regarding the effect of each conjugated linoleic acid (CLA) isomers on component of metabolic syndrome. Relevant studies were identified by searching scientific databases of PubMed and ISI during 2000 until 2012. Clinical trials and experimental studies regarding the effect of 9 cis، 11 trans and 10 trans، 12 cis and mixed CLA on component of metabolic syndrome including insulin resistance، obesity، dyslipidemia and hypertension were included in this systematic review. From 320 articles that were found in this area، 24 articles that had the inclusion criteria were selected. Most of the experimental studies have shown that conjugated linoleic acid can improve insulin resistance and lipid profile in animals، whereas clinical trials could not demonstrate this effects of CLA on humans. Each isomers of CLA have different effects، that is، 9 cis، 11 trans have role in reducing insulin resistance and improving lipid profile and 10 trans، 12 cis isomers have role in improving hypertension.

Obesity is a chronic and multidimensional disorder which is related to adipose tissue. It is well agreed that environmental factors are more important than genetic factors in the etiology of obesity. Some important environmental factors include dietary habits، food intake، physical activity، and sleep duration. Most of the available studies have focused on energy intake and physical activity. However، there are limited data regarding the association between sleep duration and body weight. Hence، in this review article، the association of sleep duration and body weight among adolescent and adults was assessed. Using search motor of PubMed، papers with various methodological designs (cohort and cross sectional) which were published during 1990 and 2012 were detected. It was found that adults who sleep less than 6 hours a day are more likely to be obese. Moreover، the inverse association between sleep duration and body weight was shown among adolescents. Nevertheless، the positive association between short sleep duration and body weight was found among older adults. The most important limitation of the available studies is the lack of information regarding the causes of short sleep duration. It seems that short sleep duration is associated with obesity and overweight especially among younger adults and children.

One of the factors leading to peace is faith and good and worthy morals. For that the human feels the sense of joy and results in vitality and mental health. Consequently it leads to physical health and impel human to right activities in life. One of the biggest goals of Islam is evolving the moral minds، as so the holy Prophit (SAW) said: “I came to do with the most ethics”. Desirable ethics by eliminating hatred and capturing the hearts will provide grounds for good social relations and comfort. Imam Ali (AS) said “everybody has a nice ethic، will level up the way of life for him”. Thus this research aimed to evaluate the role of ethic on the moral mind from the view point of Imam Ali (AS). This study was a librarian research with the aim to investigate the role of desirable ethics in the moral mind and in the words from Quran، Nahj al-Balagha، and Gherrarol Hekam. First the ethic was described and then desirable ethical characteristics in the words of Imam Ali (AS) were mentioned، and each of their effects on mental health was discussed. In this study the role of ethic on the moral health from Imam Ali (AS) view was assessed. The results indicated that desirable morals are important factors influencing mental health، and desirable traits are effective in promoting it. Ethics is a set of traits، characteristics، and acquired morals which are recognized as ethics principles by humans. By remembrance of God and good morals، man achieves peace of mind and mental health. The holy Prophet (SAW) introduced the best good moral the most popular kind of person and Imam Ali (AS) mentioned good moral as a frontispiece feature of faith. Good moral، humility، tolerance، fairness of good moral character، forgiveness، let off، good conjecture، family visiting، forgetting the people errors، security، and equity are some of the ethics characteristics which helps to improve mental health and social relationships.

Omega-3 fatty acids have established beneficial effects for cardiovascular disease. The use of omega-3 supplements for patients with non-alcoholic fatty liver disease (NAFLD) was proposed. The purpose of this study was to review the relationship between omega-3 fatty acids intake and NAFLD. In this study، the terms such as NAFLD، omega-3 fatty acids، docosahexanoic acid، and eicosapentanoic acid were searched in PubMed search engine. 15 studies on NAFLD and omega-3 were found. Four of these studies were not fully available. Three studies were not strong in terms of design. Therefore، 8 studies were chosen. The results showed that omega-3 is a regulator of gene expression in the liver. Human studies have established that consumption of omega-3 have a role in reducing the hepatic steatosis، improving insulin sensitivity and decrease the inflammatory marker. More clinical trials should be conducted to confirm these findings. Omega-3 fatty acids may improve symptoms associated with NAFLD، but more studies should be done in this area.

Research productions especially in the forms of research articles have an important role in the scientific developments of the countries. The aim of the present study was to determine the research barriers from the point of view of academic members of Rafsanjan University of Medical Sciences، Iran. This cross-sectional study was carried out in the year 2009. The tool of gathering data was a two parts designed questionnaire. In the first part demographic characteristics and in the second part research barriers were asked. Research barriers were categorized in five sections including economical and financial، organizational، social and personal، professional and facilities. In total 61 academic members filled in the questionnaires (the response rate was 53. 5%). The minimum and maximum of respondents'' age were 27 and 57 years، respectively and the mean age was 40. 2 ± 6. 8. Forty one of the respondents (69. 5%) were male. Organizational، social and personal plus economical and financial barriers were considered as the most important ones. In order to remove the research barriers expressed by academic members، their demands must be dealt with in three levels including university and ministry authorities، university and faculties'' research authorities، and especial demands.

Disease or mortality rate map، geographically is desired for public health officials and epidemiologists. Point Poisson Kriging and Empirical Bayesian methods are used in estimating the map parameters. The aim of this study was to compare the precision of the methods in mapping of gastrointestinal cancer incidence in Iran. This study was application/ecology. The methodology was illustrated using gastrointestinal cancer data recorded in the ministry of health and medical education (in the non-infectious diseases management center) of Iran in years 2003-2007 from 336 counties. Poisson Kriging model was used to estimate the parameters of the map. Spacestat، OpenBUGS and ArcGIS9. 3 softwares were used for analysing the data and drawing maps. Mean incidence rate according to Empirical Bayesian method was 12. 99 and based on Point Poisson Kriging method was estimated 12. 64. Mean incidence rate variance using the Empirical Bayesian method was 2. 83 and based on Point Poisson Kriging method was estimated 3. 85. Maximum incidence rate according to Empirical Bayesian method was 42. 23 with variance of 2. 16 related to Sari county and minimum incidence rate was 0. 48 with variance of 0. 08 related to Sarbaz County. Maximum incidence rate using the Point Poisson Kriging method was estimated 40. 35 with variance of 0. 79 related to Sari county and minimum incidence rate of 0. 30 with variance of 2. 54 related to Sarbaz County. Poisson Kriging estimation method yields smaller standard error compared to Empirical Bayesian model. The Poisson Kriging method was recommended for estimation of disease mapping parameters since it generates less smoothing and yields smaller standard error.

Sound is one of the environmental factors which can cause physical as well as psychological damages and also affect the individuals’ performance and productivity. The present study aimed to determine the effect of noise exposure on human performance. The present study assessed the effect of noise on the performance of 50 students of Shiraz University of Medical Sciences، Iran، (25 males and 25 females) at the sound pressures of 70، 90، and 110 dB by using two factors of physical features and the creation of different conditions of sound pressure source as well as applying Two-Arm Coordination Test. The results of the present study revealed no significant difference between male and female subjects as well as different conditions of creating sound pressure regarding the length of performance (P > 0. 05). In addition، as the sound pressure increased، the length of performance increased as well. According to the results، no significant difference was found between the performance at 70 and 90 dB. On the other hand، the performance at 110 dB was significantly different from the performance at 70 and 90 dB (P < 0. 05 and P < 0. 001). In general، as the sound pressure increases، the performance decreases which results in a considerable increase in the individuals’ rate of error.

Work place stress affects the mental health، performance and safety of nurses and their patients in health care centers. Accordingly، this study aimed to assess the mental health and stressful life events of nurses working in Tehran Emergency Medical Service، Iran. This was a descriptive correlational study. Two hundred nurses working in 115 Tehran Emergency Center were randomly selected. Data was collected using General Health Questionnaire (GHQ)، scaling of life events and were analyzed using SPSS software version 16. There was a statistically significant relationship between mental health and stressful life events (P < 0. 001). Mental health status of bachelor nurses was better than operating room and anesthetic technicians (P < 0. 001); and they had experienced less stressful events (P < 0. 001). To select the right people for the job، it is recommended that psychological tests such as personality traits be performed at the beginning of employment. Regular education programs and psychological counseling for these individuals is also recommended.

Adolescence is the key period for smoking initiation، and identifying predictors of smoking is critical to tobacco control programs. This study tested the role of smoking self-identity in the theory of planned behavior (TPB) model to predict the adolescents'' smoking behavior. The data were derived from a cross sectional study among 250 male high school students (mean age of 16. 21 ± 1. 45) at the Zarandieh، Iran. A multiple-stage randomized sampling protocol was used. The participants completed an anonymous، voluntary، self-report questionnaire designed based on TPB model and smoking self-identity. Data were analyzed by SPSS16، and Lisrel8. 8 software. The results indicated that the original version of TPB، has a better fitness (AIC = 31. 87، CAIC = 95. 57، ECVI = 0. 088) compared to the TPB developed by the smoking self-identity (AIC = 54. 42، CAIC = 176. 77، ECVI = 0. 15). The TPB constructs with smoking self-identity accounted for 52% of intention and 37% of smoking behavior variance. The TPB model covered 52% of intention and 35% of smoking behavior variance. The findings did not provide empirical support to the idea that the TPB might benefit from being extended with self-identity in predicting intentions and behavior. In addition، the results indicated that PBC play a more crucial role than the other TPB components in intentions to try smoking. Indeed PBC should be considered when developing tailored interventions for the prevention of smoking among adolescents.

Aggressive behavior in adolescence can be expressed as a predictor for crime، substance abuse، depression and academic failure. This study was performed with the aim to determine the prevalence and factors associated with aggression among adolescents. The present study was a cross sectional research that was performed among adolescents of Yasuj، Iran in 2010. Subjects were selected by random sampling method from the city’s main squares. Data collection tool was a questionnaire including two parts: demographic and Boss and Perry aggression questionnaire، which was completed by self-report of the participants. Data were analyzed by SPSS software version 18. Prevalence of aggression was 32. 2 percent. Drug abuse، alcohol consumption، unprotected sex، drug abuse in friends، and parental divorce had a statistically significant relationship with the incidence of aggressive in adolescents (P < 0. 05). Prevalence of aggression was 32. 2 percent. Drug abuse، alcohol consumption، unprotected sex، drug abuse in friends، and parental divorce had a statistically significant relationship with the incidence of aggressive in adolescents (P < 0. 05).

Among all methods، organic agriculture is one of the ways that protects the environment. Given the important role of agriculture experts in promoting organic agriculture، and the importance of the experts’ knowledge in this field، the present study aimed to assess the knowledge of experts of the ministry of agriculture on organic agriculture in 2011. This was a descriptive correlational study. The study population was experts who worked at agricultural ministry and the method of sampling was stratified sampling. The size of statistical sample was calculated 154 persons by Cochran table. Researcher made questionnaire was used to collect data. Validity and reliability were confirmed. SPSS19 software was used for data analyzing. The mean age of experts was 44 years and the youngest and oldest persons were 30 and 60 years old. Overall، the experts had an average knowledge about organic agriculture goals but they had a high knowledge about organic agriculture principles particularly about health principle. There was a significant positive correlation between experts’ knowledge and the number of training courses. The results showed an average knowledge of the experts regarding organic agriculture. They had more knowledge about common categories than specialized categories. This can be grounds for better training programs. Regarding the findings of the correlation، the training courses increase the experts’ knowledge on organic agriculture and it should be considered in the educational programs.