JOURNAL OF SCHOOL OF PUBLIC HEALTH AND INSTITUTE OF PUBLIC HEALTH RESEARCH
Year:2007 | Volume:5 | Issue:3|Papers Count:10

Background and Aim: Type 2 diabetes mellitus is a heterogeneous disorder resulting from a combination of genetic and environmental factors which contribute to pathogenesis by influencing beta cell function and tissue insulin sensitivity. Protein tyrosine phosphatase 1B (PTP1B)\ efficiently dephosphorylates the insulin receptor and attenuates insulin signaling. Recently, a l484insG variant of the PTP1B gene was linked to increased risk of the metabolic syndrome in an Italian population, but this was not confirmed in subsequent studies. The purpose of this research was to investigate the association of l484insG polymorphism of the PTP1B with obesity, insulin resistance, type 2 diabetes and other cardiovascular-related traits in an Iranian population.Materials and Methods: The genotypes of l484insG variant were determined by the PCR-RFLP method in 242 unrelated subjects, including 171 individuals with normal glucose tolerance and normal fasting glucose levels, and 71 type 2 diabetics. Insulin resistance was assessed using the homeostasis assessment model.Results: The allelic frequency of the l484insG polymorphism among type 2 diabetic patients and non-diabetic individuals was 6.3% and 3.8%, respectively (p=0.205). None of the subjects were homozygous for the l484insG allele. Concerning quantitative traits in non-diabetic subjects, carriers of 1484insG allele had significantly higher body mass index (p=0.01), diastolic blood pressure (p=0.012), and HOMA-IR (p= 0.041) levels compared to those carrying the wild-type genotype.In type 2 diabetics, carriers of l484insG allele had only significantly higher HOMA-B (P= 0/04) level compared to the individuals with the wild-type genotype. Conclusion: Our results from a sample of Iranian type 2 diabetes cases and controls provide evidence that the l484insG genotype of the PTP1B gene may be associated with obesity and insulin resistance.

Background and Aim: Exposure to hexavalent chromium in plating operations is associated with skin ulceration, contact dermatitis, respiratory tract irritation, cancer, and kidney damage. We investigated the possibility of using biological monitoring to assess exposure to hexavalent chromium in chrome-plating workers. We compared mean Cr6 concentrations in the breathing zone plus urine chromium, b2 microglobulin (B2M), and N-acetyl-B-D- glucosaminidase (NAG) at the end of the working shift. Then we assessed the correlation between exposure to hexavalent chromium and biological indicators.Materials and Methods: This study involved 45 chrome platers (Cases) and 40 zinc platers (Controls) in Isfahan. Air and urine samples were collected at the end of the work shift. Measurement of Cr6 concentrations in the workers' breathing zone was performed using the NIOSH Methods 7600. Urine Cr levels were determined by atomic absorption spectrophotometer, with a graphite furnace (Shimadsu, AA680). B2M and NAG were measured by Kits.Results: Overall, geometric mean of hexavalent chromium concentrations in the breathing zone was significantly higher among chrome platers (14.577 mg/m3) compared to zinc platers (0.862 mg/m3, p<0.001). Moreover, the mean urine Cr concentrations were higher in chrome platers (9.198 vs. 1.811mg I g creatinine, p<0.001) .Similarly, there were significant differences between mean NAG in chrome platers (12.608IU/gr creatinine) and zinc platers (6.824 IU/g creatinine, p<0.001).Differences in B2M concentrations were not significant (p>0.05). A significant correlation was found between Cr6 concentrations in the chrome platers' breathing zone and their urinary chromium levels (r= 0.838, p<0.001). A similar association was found between concentrations of Cr6 and NAG in the breathing zone (r= 0.304, p<0.05). Conclusion: As urinary B2M concentration did not change significantly, it may not be a sensitive indicator in evaluating exposure to hexavalent chromium. There were significant differences between mean urinary Cr and NAG concentrations in the two groups. The significant correlations between Cr and NAG concentrations indicate that these markers may be suitable indicators of exposure to hexavalent chromium. Our results indicate that NAG is an early indicator of renal dysfunction in chrome platters.

Background and Aim: Patients with hemophilia and thalassemia are at high risk for hepatitis C virus (HCV) infections. Unscreened blood and blood products are thought to be the most important risk factors in these two groups.Materials and Methods: Blood samples were collected from 98 thalassemia patients and 74 hemophiliacs in Markazi province. The presence of anti-HCV antibody was tested by a third generation enzyme immunoassay. All ELISA-reactive samples were tested with the confirmatory third-generation recombinant irnrnunoblot assay RIBA. We used a specially designed questionnaire to obtain data from patients and the software package SPSS 11.5 for statistical analysis.Results: HCV antibody was detected in 5 thalassemia patients (5.1%) and 31 hemophiliacs (41.9%). Anti-HCV positivity in patients with thalassemia was associated with the total volume of the transfusions, splenectomy, and the duration of treatment. In hemophiliacs, seropositivity was significantly associated with the duration of transfusion treatment (P=0.01) and disease severity (P=0.00).The prevalence of HCV antibody in thalassemia subjects dropped from 8.1% to 0% after the implementation of anti-HCV screening in1996. Conclusion: In Markazi province, the current policy of screening donors for anti- HCV and the strict safety controls on factor concentrates can effectively protect thalassemia and hemophilia patients from HCV infection.

Background and Aim: Cutaneous leishmaniasis (CL) is endemic in Iran and many other countries. The use of pentavalent antimony compounds for the treatment of this disease is associated with serious side effects. There have been reports of the effect of the extract of Berberis vulgaris root on leishmania major, both in vitro and in vivo. The goal of the present study was to investigate the effect of an alcoholic extract of this plant on experimental 1. major ulcers in BALB/c mice. The experiment was conducted in 2006 by the Department of Parasitology, Kashan University of Medical Sciences.Materials and Methods: We used different concentrations of an alcoholic extract of Berberis vulgaris in the form of an ointment. Ninety BALB/c mice received a subcutaneous inoculation of 0.1 ml liquid-phase culture of infective 1. Major (MRHO/IR/75/ER standard variety) in the base of their tail. Ulcers appeared after 30- 35 days and these were divided into 5 groups: 3 groups received treatment with 20%, 40%, and 80% concentrations and the remaining 2 groups served as controls. The extract was used applied topically, three times a day for 30 days. Each weak we measured the diameter of the lesions and the animals' weight. After preparation and staining, we determined the number of parasites in lesions through microscopic examinations. Results were recorded on paper and analyzed with the use of Student's t and Fisher's exact tests as well as analysis of variance and Tokey's post-hoc tests.Results: With the 20% preparation: By the end of the treatment period, the mean diameter of the lesions had decreased, with complete healing in 5 mice (27.7%), (p< 0.001). By the time of the decrease in diameter, the mean weight of the animals had increased and the number of parasites in the lesions had declined (80%). Total elimination of the parasites was observed in 12 animals (p<0.001).At a concentration of 40%: Mean ulcer diameter decreased, with complete healing in 2 mice (11.1%, p<0.001). By the time of the decrease in diameter, the mean weight of the mice had increased (p<0.05). The mean number of parasites in lesions decreased (64.3%), with total elimination in 9 animals (p< 0.05).Conclusion: We showed that the extract of Berberis vulgaris is most effective at a concentration of 20%, causing greater reductions in both ulcer diameter and the number of parasites , in the lesions compared to other preparations. Therefore, we suggest the use of a 20% extract for the treatment of human cases.

Background and Aim: Intestinal parasites cause significant morbidity and mortality and are considered by the World Health Organization as a public health problem of global importance. These agents are estimated to infect more than three billion people worldwide. In Iran, thanks to long-time efforts by the national health system (including environmental sanitation and public education campaigns), the frequency of the most intestinal parasitic infections has significantly declined in the recent decades. Our study aimed to determine the prevalence of intestinal parasites in a highrisk occupational group, namely the municipal workers in the city of Esfahan.Materials and Methods: A survey was conducted to determine the prevalence of intestinal parasitic infections among municipal workers in several districts of Esfahan. Specimens were placed into fecal pots, labeled and kept cool before being transported to the Health Research Center Laboratory, affiliated to the School of Public Health & Institute for Public Health Research in Tehran University of Medical Sciences. The technique used for identifying infections was stool concentration by formalin & ether. All the slides were carefully studied using light microscopy with x10, x 40, and x100 magnification.Results: The study results revealed that 24.6% of the workers harbored at least one parasitic species. The highest prevalence (36%) belonged to Giardia lamblia. Ascaris lumbricoides was the most common helminthic parasite (12.4%), followed by Hymenolepis nana (1.2%). The most common non-pathogenic protozoal species was Entamoeba coli (21.7%).Conclusion: Infection with soil parasites is dependent on environmental conditions that allow parasites to complete their life cycle. Socioeconomic and cultural factors are important for the appearance and spread of intestinal parasites in communities where sanitary conditions and infrastructure are inadequate. However, soil-transmitted helminthiasis (STH) used to be prevalent throughout the country, especially in urban and rural population of the Esfahan Province. We investigated the prevalence of intestinal parasites by fecal examination of workers in Esfahan municipality, a group with a low-sanitation working environment close contact with soil contaminants. The lack of information on prevalence in the general population makes it difficult to arrive at any definite conclusions, but on the basis of unpublished data we can conclude that prevalence is somewhat higher in this occupational group compared to the population at large.

Background and Aim: Although there have been several epidemiologic studies on first permanent molar caries in Iranian students, the need for endodontic therapy has not been investigated so far.The purpose of this study was to assess the need for first molar root canal therapy in 7- to ll-year-old schoolchildren and its association with age, gender, and parent education level.Materials and Methods: We selected 885 students (572 girls and 313 boys) from 12 elementary schools, using a random cluster sampling method. We recorded the subjects' identities and examined their maxillary and mandibular first molars with a mirror and an explorer. In case of any doubts about the need for endodontic therapy, we performed vitality tests and/or obtained periapical radiography. Chi-square and Mann-Whitney tests were used for statistical analysis.Results: In 26 students (3%) there was an indication for endodontic treatment of the first molars. Of these, 18 teeth were in mandible and 8 in the maxilla. The need for endodontic therapy was significantly related to the subjects' age and the parents' education level. We did not detect a significant association between gender and the need for endodontic therapy.Conclusion: We recommend pit and fissure sealant plus fluoride therapy, beginning with the eruption of the first permanent molars- especially in the mandible.

Background and Aim: Hospitals are among the most important health and medical institutions responsible for promoting health, and provision of appropriate health services requires a healthy, hygienic and safe environment. This research was done with the aim of assessing the environmental health situation Qom hospitals in 2005. Materials and Methods: This research is an applied descriptive- analytic study on hospitals in QOM Province. Data were gathered using survey and observation methods and a two-part questionnaire. The first part of the questionnaire consisted of 45 items covering demographic data on hospitals and hospital managers. The second part comprised 363 questions about the environmental health situation as well as diagnostic, treating and support services. The questionnaires were filled after validity and reliability tests in eight hospitals in Qom Province. For statistical analysis, we performed Mann-Whitney and Kruskal-Wallis tests and calculated Spearman's coefficient, using the software package SPSS.Results: Poor environmental health was observed in 25% of the radiology wards, kitchens and laundries. The situation was assessed as "appropriate" in 12.5% of laboratories and central sterilization (CSR), 25% of emergency services, 50% of ICD wards and 71% of surgery and recovery rooms, and it was intermediate of the other wards. Overall, the level of compliance with the principles of environmental health was average, i.e. about 72.5 percent. Further analysis of data showed that the situation was better in private, non-teaching hospitals compared to government-run and teaching hospitals. However, environmental health was found to improve with an increase in the number of active hospital beds and the managers' experience in their current job. It declined with increasing hospital age and increasing age of the hospital managers.Conclusion: Overall, the environmental health situation in Qom hospitals was found to be at an intermediate level. Hence, these hospitals have a long way to go before they can achieve the appropriate level of environmental health.

Background and Aim: In this research we isolated the bacterial species degrading polycyclic aromatic hydrocarbons (PAHs) and determined optimal salt concentration for PAB degradation.Materials and Methods: We used naphthalene and anthracene as the only sources of carbon for isolating PAH-degrading bacteria; the main culture medium was ONR7a.The bacteria isolated by this method were used for the study of the effect of salt concentration on PAH degradation.Results: Pseudomonas is the only PAH-degrading bacterium isolated from the lake's water and sediment. The greatest numbers of naphthalene- and anthracene-degrading bacteria where found in the water and sediment from the Khoshk River (mean counts: 227 and 167 per ml water and 290 and 193 per gram of sediment). The mean counts of naphthalene- and anthracene degrading bacteria in Pol- Fasa River were 107 and 73 per ml water and 157 and 127 per gram sediment, respectively. Values from Nazar Abad River were 27 and 17 Icc water and 43 and 20 I g sediment. In the center of the lake counts were 63 and 33 per ml water and 123 and 73 per gram sediment and in the western part of the lake counts were 30 and 13Iccl water and 43 and 17 Ig sediment. Maharloo lake is located in south-east of Shiraz, 23 km from the city and contains saline water with a mean salt content of 220 g/L. Among the most important pollutants entering the lake are polycyclic aromatic hydrocarbons (PAHs). Our research showed that overall, naphthalene-degrading bacteria are present in greater numbers compared to anthracene-degrading bacteria. The optimal salt concentration for the growth of Pseudomonas spp growth and PAH-degradation is around 6% the rate of degradation increases with time. Conclusion: Regarding isolation of PAHs degrading bacteria from the lake, it is obvious that part of the degradation is done by bacteria. The main bacterium here is pseudomonas and it is optimally active at a salt concentration of 6%.