مجله تحقیقات نظام سلامت
سال هفتم شماره 2 (خرداد و تیر 1390)

Cancer is a major public health problem and one of the leading causes of death worldwide. Lifestyle factors including dietary patterns are a major determinant of increasing rates of cancer. Sugar-sweetened beverages (SSBs) have recently received great attention due to their effects on hyperglycemia, hyperinsulinemia, reduced insulin sensitivity, and obesity as well as their probable relation with cancer. This study aimed to review the current literature on the association between of sugar sweetened beverage intake and pancreatic cancer. We searched MEDLINE and PubMed databases for “sugar sweetened beverage”, “soda”, “soft drinks”, “cancer”, “adenoma”, and “carcinoma”. Totally, 9 studies were extracted. Animal and human studies with case-control and prospective designs related to non-alcoholic beverages and risk of pancreatic cancer were included in this review. Publications on natural and alcoholic beverages as well as those related to other conditions were excluded. Findings from most available prospective cohort studies suggest no significant associations between consumption of sugar sweetened beverages and risk of pancreatic cancer. However, case-control studies indicated that even consumption of low-calorie soft drinks is associated with greater chance of having pancreatic cancer. An animal study also demonstrated a significant association between SSB consumption and risk of exocrine adenomas of the pancreas. High consumption of sugar sweetened beverages might increase the risk of pancreatic cancer due to their effects on obesity and insulin.

In order to eliminate and reduce noise in predesigned and installed heating, ventilation, and air-conditioning (HVAC) systems, noise control in HVAC system areas needs to be performed using plenum chambers based on ASHRAE method. A plenum chamber made of galvanized iron was produced based on ASHRAE standards. The length, height, and width of the chamber were 1.5 meters, 1.1 meters and 1.2 meters, respectively. Two input and output openings (40 × 20 cm) were also made. The internal surface of the chamber was lined by 10 cm thick mineral wool with a density of 80 kg/m3. The results show a noise reduction of 2.3 to 13.2 dB with a peak at 250 Hz in 1/1 octave band frequency based on ASHRAE standard method. Generally, highest levels of noise reduction were observed in medium to high frequencies. The most important conclusion revealed by this study is that based on ASHRAE standard, dimensions of the plenum chamber and acoustic specifications of absorbent material applied into the chamber can highly affect the level of noise reduction. In fact, we can change the noise reduction value by changing the dimensions of the plenum. For low frequencies, as said before, it is better to use a bigger plenum chamber.

Job strain includes physical or psychological symptoms appearing due to a stressor reception in workplace. People use coping resources to deal with these problems. Thus, after identifying the kind of stress, education must be performed to diminish or delete any hazardous health effects. Among all other factors, behavioral factors can potentially promote education and health. This study aimed to investigate the relation between job strain and health behaviors in employees of Islamic Azad University, region 4. This descriptive correlation study was performed on 197 randomly (cluster sampling) selected employees of Islamic Azad University, region 4. A questionnaire was completed by the staff to collect data. The results from this study revealed significant correlations between job strain and health behaviors such as diet (P ≤ 0.001), sleep (P ≤ 0.003) and income levels (P≤ 0.01). The present study demonstrated job strain to have many potential effects on employee's health. Therefore, workplace health promotion strategies can lead to job redesign, lower psychological job demands and higher job control in employees.

breast cancer as a most common organ cancer in women is the first cause of death among women with 40-45 years old. The only way to control this disease is early detection that it can be treated in about 90% of women with breast cancer. The best way for early detection of breast cancer is screening, and the best accessible way is breast self examination (BSE). Considering this fact that female health workers are responsible for improvement of public health, in addition to self care, they can encourage the clients and help to improve healthy goals. Therefore this study, investigates the Knowledge, attitudes and practice of Breast Self - Examination among female health workers. This descriptive cross sectional study was done among 119 female health workers in Isfahan. The method of sampling was clustering. With KAP questioner knowledge, attitude and practice of theses participants was assessed. The data collected were analyzed using descriptive and inferential statistics methods. The mean age of participants was 38/3± 7/27. The knowledge about breast cancer and doing breast self examination (BSE) was good (79/8%) in most participants and (72/45%) of them have positive attitudes but only (39/5%) of the samples performed BSE regularly every month. A significant relationship was found between attitudes and the university degree of the health workers and also between age, university degree and the times of taking part in education classes with performing BSE in the best time for breast self examination.(P<0.005). 12/6% of them did not have a good performance. considering that health workers can play an important role on encouraging the clients to perform healthy and preventive behaviors, their weak behavior is not acceptable in these groups. This result also shows that additional studies are needed to identify the factors that make women using screening services and encourage them for using these methods.

Noorabad-e-Mamasani has the highest rate of delivery by cesarean section in Fars province. Cesarean section, as a large surgical operation, is accompanied with some side effects that sometimes get very dangerous and rarely lethal. The present investigation aims to determine the effects of a health belief model-based educational intervention on decreasing cesarean sections among the mentioned city's pregnant women in 2009. In this quasi-experimental study, 100 primiparous pregnant women, in their third trimester, were randomly categorized into two groups of case and control.The educational plan was designed based on the health belief model (HBM). Before implementation of the educational plan, a questionnaire, based on the HBM structures, was completed by the two groups. The case group received HBM-based education (6 educational sessions during three consecutive days). Pregnant women of the both groups completed the questionnaire for a second time 4-8 weeks after the intervention.The collected data was analyzed using SPSS 14 software and by independent-t, t-paired, chi- square, Wilcoxon, and Mann Whitney statistical tests. Participation of individuals in this study was voluntarily and with informed consents. Findings of the present research showed a meaningful difference in the mean scores of awareness (P < 0.001), perceived susceptibility (P < 0.001), perceived benefits (P < 0.001) and perceived self-efficacy (P = 0.02) between the two groups after the intervention. However, no significant difference was observed between the two groups about perceived barriers (P = 0.09), intention for choosing the delivering type (P = 0.73), and behavior (P = 0.24) after the intervention. Results of this study indicated the effectiveness of health belief model-based educational plan on increasing the awareness and attitudes of pregnant women towards delivery. However, considering the numerous factors that may affect choice of delivery method, increased awareness and attitudes do not necessarily lead to the desired behavior. Therefore, in order to boost the efficiency of this model, it is important to take advantage of other models that influence health policy making and abstract norms.

In most industries, including paint manufacturing, workers are exposed to toluene. Absorbed toluene in liver is metabolized and is exerted as urine metabolites, such as ortho-cresol. Due to different reasons, the only possible way to reduce exposure in some industries is using personal protective equipments. This study uses urine biological monitoring to examine the efficiency of a respiratory protective equipment in toluene exposure reduction among workers. Production line workers of three paint industries (22 Subjects) were studied. When the workers were not using respiratory protective equipment, their average respiratory exposure to toluene was measured during a shift. The next day, the average toluene respiratory exposure of the same workers during a shift was measured while they were using air purifying respirator masks with A1/organic vapor filters. In addition, their urine samples, collected at the end of the shifts, were sent to the lab for determining the amount of ortho-cresol. Urinary ortho-cresol measurement was carried out by NIOSH 8305. Sampling and measuring of existing toluene in workplace air was done by NIOSH 1501. No statistically significant difference was observed between the average toluene exposure levels on the first and second days (P = 0.026). However, the average respiratory toluene calculated by a formula based on urinary ortho-cresol revealed a significant difference between the two days (P < 0.05). Using related formulas and considering a 20% reduction in inhaled toluene, the average efficiency of respirator was found to be 42.6% with a protective factor of 1.7. According to NIOSH standard, protective factor for the respirators used should be 10. So, according to our results, this kind of respirator does not have sufficient efficiency for reducing toluene exposure and it cannot be used as a safe way for protecting workers against chemical pollutants.

psychiatric disorder is a disease in which patients suffer from emotional problems that these are visible in all aspect of patient’s life. Studies show that there is a major difference between the prevalence of this disease in different countries and also show that this disorder is increasing. The aim of this study is to find the possible relationship between psychiatric disorders and epidemiological characteristics of the patients. this was a cross-sectional study in which 3935 patients were recruited from 2004 to 2010. the patients were diagnosed to at least one of the following disorders such as anxiety, cognitive, behavioural, substance abuse, bipolar I &II &NOS, psychotic, psycholotemic, and depression. The distribution of each psychiatric disorder and its related factors were analysed using logistic regression method. Ratio of male to female was 1.2. The mean±SD of the age of the patients was 33.1±0.2 that showed men were younger than women. Bipolar I, psychotic, and depression were respectively highest frequencies among the other psychotic disorders. The higher the age, the higher the chance of suffering from depression, cognitive disorder, and substance abuse and the lower the chance of suffering from bipolar I and psychotic. The odds were higher for smoker to suffer bipolar I, NOS, and drug use disorder than non-smoker. Also, patients with more hospital admission were more at risk of anxiety, bipolar I, II, and psychotic disorders. In previous studies the odds of suffering from psychotic and bipolar disorder was higher in patients with hospital readmission as was seen in this study. In this work women were seen to be more at risk of anxiety, bipolar and depressive disorders than men and also males were more prone to drug use and psychotic disorders compared to females. These results are similar to the previous studies.

Heat stress is one of the most important consequences of occupational heat exposure worldwide. Current heat stress indices are not suitable for heat strain screening in developing countries, due to their inherent and applied limitations. This study aimed to design and investigate content validity and reliability of a pen-paper method for preliminary assessment of heat stress at work.

This cross-sectional study was conducted during 2009-2010. This research included three stages: (i) item generation based on literature review and interview; (ii) evaluation of content validity by 9 occupational health specialists and 30 occupational health providers; and (iii) reliability analysis performed on 98 workers.

Forty items were identified during item generation stage. In content validity evaluation stage occupational health specialists modified 27 items, removed 3 items and added 3 other items. In addition, occupational health providers modified 19 items. In reliability analysis, 15 items with item-total correlations less than 0.2 were omitted. Internal consistency (Cronbach's α) of the 25 remained items was 0.90.

The 25 measurable variables in our questionnaire were highly consistent with Wet Bulb Globe Temperature (WBGT) heat strain index and other questionnaires. Moreover, this questionnaire demonstrated high reliability. Therefore, after assessment of the structure and criteria validity, the questionnaire can be used for preliminary evaluation of heat stress in Iran.

The aim of the current study was to assess the cross reaction of the crude hydatid cyst fluid (HCF) antigens of Echinococcus granulosus, obtained from mice experimentally infected with hydatid cyst and from naturally infected human using sera of infected human who had surgery at different hospitals in Iran. hydatid cysts obtained from lungs and livers of naturally infected sheep slauthered from local abattoirs in Ilam, Iran. HCF recovered from cysts was centrifuged at 10000 rpm for 25 minutes. The supernatant was dialysed against PBS, freezed- thawed and used as crude HCF. HCFs obtained from two different host species were highly useful for ELISA and most sera from CE patients equally recognized the HCF antigen of both mice and human. Mice sera showed a cross-reaction with human sera in recognition of HCF antigens of echinococcosis. IgG4 was the highest IgG subclass recognizing HCF of both mice and human HCF. Human IgG was high in response to both antigens while the OD ratio was two times using human IgG against mice antigen compared to human antigen. IgG and IgG4 of human sera are reacting against both mice and human HCF with the greatest response from IgG total to mice HCF. Cross reaction of human IgG and IgG4 was observed for both mice and human HCF. Mice HCF can be relied on as an appropriate antigen in detection of human hydatidosis.

Biofiltration is one of the most effective methods for pollutant removal from a gas stream. An accurate mathematical model to predict removal efficiency can be applied in design and optimization of such equipment and also in investigating biofiltration process.The objective of this study was to develop a mathematical model for predicting biofiltration process performance in hydrogen sulfide removal from a gas stream and also examining the influence of several main parameters such as biofilm diffusivity and biofilm thickness on the predicted results. In order to achieve the goals, the governing equations expressing mass conservation for a differential control volume in both gas and biofilm phases were solved. Hydrogen sulfide concentration distributions in gas and biofilm phases were determined by solving these equations. The presented model is capable of predicting the variation of biofilm thickness through time due to bacteria growth and biofilm surface abrasion. The results from the expanded mathematical model were well in agreement with empirical data. The results revealed that hydrogen sulfide removal efficiency increases by increments in packing specific surface area and biofilm diffusivity along with decreasing entering gas velocity. In addition, the results of the model showed that increasing biofilm thickness tends to raise the removal efficiency for biofilm thickness of less than 5 micrometer. This fact reveals that the reaction rate is the rate-controlling step for lower biofilm thickness and the biofilm-diffusion resistance does not affect mass transfer rate significantly. However, further increasing biofilm thickness (to more than 20 micrometers) causes hydrogen sulfide removal efficiency to decrease. It can be attributed to magnifying the influence of biofilm diffusion on mass transfer rate.

Type 2 Diabetes is one of the most serious health concerns and policy agendas around the world. Epidemiological evidence suggests that it will likely continue to increase globally. Diabetes is strongly associated with the patients’ unhealthy lifestyle and behavioral patterns and socio-economic changes.New model of thinking is required to recognize whether the patients are in control of and responsible for the daily self-management of diabetes. Such a new approach should be based on ‘empowerment and involvement’ to be more applicable to daily activities in diabetic patients.Rapid changes toward patient empowerment and increasing involvement of patients in their care plan indicate more emphasis on disease prevention and health promotion and education than on mere disease and its treatment. Such changes make a step toward pervasive sense of responsibility among patients about their illness for their daily activities.Using the empowerment approach, healthcare professionals would help patients make informed decisions in accordance with their particular circumstances. Patient empowerment implies a patient-centered, collaborative approach that helps patients determine and develop the inherent capacity to be responsible for their own life.Empowerment is something more than certain health behaviors. Empowerment is more than an intervention, technique or strategy. It is rather a vision that helps people change their behavior and make decisions about their health care. It has the potential to improve the overall health and well-being of individuals and communities, and to change the socio-environmental factors that cause poor health conditions. The main concept of this change is the tendency to change.