JOURNAL OF RESEARCH IN MEDICAL SCIENCES (JRMS)
Year:2001 | Volume:6 | Issue:Supplement 2|Papers Count:22

In many casses the estimation of variance which is used to determine sample size in clinical trials, derives from limited primary or pilot studies in which number of samples is small. since in such casses the estimation of variance may be much far from the real variance, the size of samples is suspected to be less or more than what is really needed. In this article an attempt has been made to give a solution to this problem. in the case of normal distribution. Based on distribution of (n-1) S2/σ2 which is chi-square for normal variables, an appropriate estimation of variance is determined an used to calculate sample size. Also, total probability to ensure specific precision and power has been achived. In method presented here, The probability for getting desired precision and power is more than that of usual method, but results of two methods get closer when sample size increases in primary studies.

Introduction: intestinal parasitic infection is considered as one of the important health indices and the differences in it"s prevalence in different communities, explain the need for the periodical study of the prevalence inorder to organize, convenient preventative programs. previous studies have shown that prevalence of parasitic infection in rural areas is higher than urban areas. Therefore in this survey for the first time, the prevalence of intestinal parasitic infections in relation to some of the demographic parameters was studied in rural areas of the city of mobarakeh of Isfahan province in 1997. Methods: Two methods were used to detect the presence of intestinal parasites; direct exam and fecalcontrate system: formalin ethyl acetate method. The scotch tape method was used to examin for Enterobius vermicularis. Results: 51.9 percent of the studied children were infected by one or several intestinal parasites. The most prevalent intestinal parasite was Giardia lamblia (29.8 percent), Entamoeba coli (17.1 percent) and Enterobius vermicularis(16.3 percent) respectively. A significant relation was found between age, level of education of mother and father, weight at birth, number of children in the family, and parasitic infections (P< percentS). No significant relationship was observed between sex and parasitic infections (P> percentS). Discussion: A comparison between the present results and those reported previously indicates that there is not a significant differences between the prevalence of parasitic infection in rural and urban parts of Isfahan province. Intestinal parasitic infections is still an important health problem in the region and the control and prevention demands more consideration of authorities.

Introduction: Trichomoniasis (infection with Trichomonas vaginalis ) is the second cause of vaginitis after bacterial infections and the most prevalent non virel sexually transmitted disease. Considering the differences in the prevalence of infection in other countries and the lack of any study of frequency of infection in Isfahan in the last 20 years in this survey the frequency of infection with T. vaginalis in women attending to health care centers and the relationship between infection and demoghraphic factors and clinical signs was studied. Methods: The diagnosis of Trichomoniasis was made by wet mount examination and culture of vaginal discharge in 470 women attending to three health care centers in Isfahan. The relationship between the results obtained and clinical signs and demographics factors determined by questionnaires, interviews, and physical examinations was investigated. Results: From 470 women, in 7 (1.49 percent) and 9 (1.92 percent) cases indentified T.vaginalis in wet mount and culture respectively. Statistical methods showed no significant relationship between Trichomoniasis and age, Use of specific contraceptive method, and vaginal pH (for those with no clinical signs) (P>0.05). However, a statistically significant relationship was observed between Trichomoniasis and pruritus, irritation of vulva, frothy discharge, vaginitis and vaginal pH (in women with clinical signs). (P<0.05). Discussion: A comparison between the results of the present study and the previous ones showed a significant decrease in the frequency of T.vaginalis in Isfahan. This dicrease may be due to some changes in the social behaviors and more comitment to the Islamic principles. It seems that there is no direct relationship between Trichomoniasis and age but pH changes may be one of the factors involved in Trichomoniasis.

Introduction: Natural plant coagulants have an important role to play in provision of portable water to rural communities in the developing world. The plant material that their coagulation properties have been confirmed in previous lab scale studies and can be found widely in Iran was selected as coagulant aids. Pilot plant study was done to evaluate the efficiency of natural material such as Starch/Gum Tragacanth, Fenugreek and Yeast as coagulant aids in conjunction with comercial alum. Methods: The pilot was placed in Isfahan Water Treatment Plant (IWTP) and efficiency of these materials in removal of turbidity from raw water enters the IWTP was evaluated. The results indicated while these materials were used as coagulant aids in concentration of 1-5 mg/l conjunction with alum are able to reduced the turbidity and final residuals turbidity meets the standards limits. Results: The coagulation efficiency of these material were found to be effected by certain physico-chemical factors, namely, concentration of suspended solids, divalent cation metal and time of agitation. The relative importance of these variable was evaluated. The results of COD test proved that the natural coagulant aids in the optimum doses produce no any significant organic residual. Discussion: Economical considerations showed that using of these material as coagulant aids can cause reduction in alum consumption and in some cases are more econmical than synthetic polyelectrolyte.

Introduction: Dischange of domestic, agricultural and industrial waste water into the rivers increase chemical substances such as nitrate and phosphate. These chemical changes increase algal population. High density of algae may cause changes in color, odor and taste of water. Some of the algae such as Oscillatoria, Microcystis and Anabeana produce toxins and in high concentrations may kill fishes. While Zayandehrud river is considered as one of the main water supply sources for drinking water and valuable water resources of Isfahan Province, water quality control of this river is important. The study of algae of the river in relation with the concentration of nitrate and phosphate is the purpose of this research project. Methods: To perform this projects, seven sampling stations from "Pole Vahid" to .Pole choom. were selected. Grab methods were used for sampling of the river water. 147 water samples were collected in one year of the study.The samples were analyzed for phosphate, nitrate and genera of the algae. Nitrate and phosphate of the water samples were determined using Phenol Disulfonic Acid and Stanous chloride methods, respectively. The genera of the algae were detennined using the keys. Results and Disccusion:The result of the study showed that the frequency of the algae increased with increasing nitrate and phosphate. Overall.35 genera of algae in the area of the study were observed, which six of them were indicators of water pollution. Minimum frequency of indicators of pollution was observed in the enterance of Isfahan city and maximum frequency was observed after the discharge of municipal water from waste water treatment plant (pole Choom).

Introduction: The improper and excess use of chemical fertilizers by the farmers special in "urea" form may cause the commulation of nitrates and nitrites in vegetables and fruits. This investigation has been done to determine the concentration of nitrates and nitrites in some vegetables growing around Isfahan. Methods: One hundred and thirteen random samples from 15 different kinds of green lest tuber vegetables were measured by Cadmium Column Procedure for nitrates and nitrites. Results: The mean of the nitrates level in green leaf and tuber-vegetables was 287.9 and 76.3 mg/kg, respectively. These amounts were more higher than standard value (67 mg/kg in the basis of wet material), significantly. The mean of the nitrite level in green leaf and tuber vegetables were 1.7 and 1 mg/kg, repectively, which were more higher than standard value (zero mg/kg in the basis of wet matrial). The most high concentration of nitrites and nitrates was seen in commondill and leek, repectively. Discussion: Amounts of nitrites and nitrates in our analysed samples exceeded the perimissible limits. The comulation of nitrates in some of the vegetables depend on the application of chemical fertilizers, temprature and wether, but the nitrites in vegetables is unusual in normal condition and the unsuitable storage of them causes it"s expansion.

Introduction: HBsAg is one of the important components of H.B. V and infection generation of the virus is related to that. In this study the prevalence of HBsAg in Eeast Azarbaijan, relative to different variables has been studied.Methods: The population of under study is residents of age 2-69 years old of this province. The required data are taken from the plan of" Health survey" that has been under provision of deputy for research of Health, treatment and medical education Ministry. Results: The number of people whose blood were examined for HBsAg, is 3409 whom 100 cases were positive (2.9 percent). The variables. place of residential, age, Economical status, axillary adenopathy and existance of parasite in feces . showed significance cortelation with HBsAg. (p-value<0.05).Discussion: By regard to that HBsAg has been related with type of drinking water and existance of parasite in feces, We can decrease the prevalence Hepatitis B in rural regions by preparing safe drinking water.

Introduction: Inadequate dietary intake causes malnutrition associated with poor physical and mental development, specially in children. This study evaluated the nutritional status in blind children in Ababasir Boarding Center (a boarding school in Isfahan city). Methods: A 72 hours food regimen survey was measured in 50 subjects (boys and girls) by weighting method. The anthropometric data was collected to compare with NCHS normal data. Results: Energy intake was less than 75 percent RDA in all the subjects and the amounts of animal protein intake was also little. Chronic malnutrition was more prevalent. Discussion: Althought the energy intake was lower than RDA, but it did not cause under weight among them probably because of reduced physical activity due to their disability and inadequate high quality protein and other nutrients probably could be the major cause in chronic malnutrition.

Introduction: Sedimentation is considered as an important process in removing turbidity produced in water and wastewater plants. Gravity sedimentation is usually the first method considered in water treatment system. However, required overflow rates (OFRs) to remove turbidity in the conventional clarifiers are too low. Therefore, the shallow depth sedimentation concept was studied remove turbidity in order to increase OFRs of gravity setting equipment. Methods: Using a pilot with parallel plates with effect area 1.5 m2 and 1.5 m depth. The independent parameters such as OFRs, sludge concentration and turbidity were evaluated for turbidity removal. The pilot is located in Isfahan Water Treatment Plant. Results: The efficacy of pilot for turbidity 10-50 NTU is equal to 50 percent (P<0.01). The maximum removal efficiency at sludge concentration 270 ml/lit was obtained (P<0.01). A nonlinear relationship exists between removal efficiency (TR%), sludge concentration (Sc) over flowrates (OFR) and influent turbidity (Tu) in pilot. Discussion: By using high rate sedimentation tank in water treatment plant, detection time reduced from 3 hours to 20-30 minute, turbidity removal increased up to 30 percent in compare with conventional sedimentation. Also, it has economic benefits and high efficiency.

Introduction: Iodine deficiency disorders (IDD) is a worldwide health problem. Many parts of the Islamic Republic of Iran had been known as areas of endemic goiter. IDD was accepted as a priority health problem in the country, and a National lDD council was formed in 1989 under the supervision of the Ministry of Health and Medical Education. One of the main strategies of National council for IDD control was to provid at least 150 g of iodine per day to the entire population through making available iodized salt. This study was performed to evaluate the national IDD council program in 1996, in rural and urban areas of Isfahan province. Methods: One thousand and four hundred schoolchildren, aged 8 to 10 year, including 50% girls and 500k boys, were selected through random sampling. Grading of goiter was performed according to WHO"s classification. Serum T3. T 4 and TSH were measured by RIA and uninary iodine by digestion method. Results: The mean of serum T 4. T3 and TSH were 10.2±1.7 µgldl, 166±97 ngldl and 2.7±0.8 µlu/ml, respectively. There were no difference between males and females and schoolchildren of rural and urban areas. 0.6 percent had serum T4 more than 12.5 µg/dl and eight person had TSH more thans 5 µlu/ml. The median urinary iodine was 21 µg/dl in entire population, 76 percent had urinary iodine more than 10 µg/dl. Only 10 percent had urinary iodine less than 5 µg/dl. Total prevalence of goiter was 58 percent (60 percent in girls and 53 percent in boys). Disussion: Based on the available data, seven years after generalized use of iodized salt and 2 years after more than 50 percent of pupulation used iodized salt, uninary iodine of school children in Isfahan province showed sufficient iodine intake. However goiter is still hyperendemic in Isfahan province.

Introduction: Foodhandlers can be carriers of organisms such as salmonella, staphylococci and intestinal parasitic infections. Considering that some patients in hospitals may have impaired resistance to infection and the possible role of foodhandlers in this regard, it seems to be necessary to examine the role of foodhandlers in transmission of intestinal parasitic infection. Methods: 152 foodhandlers were evaluated for their intestinal protozoan and helminthic infections in the hospitals of the Isfahan University of Medical Sciences. From each subject, three stool - specimens were taken in three consecutive days. Five methods (Scotch tape, Direct examination, Formalin - Ether, Telleman, Flotation) were used to detect ova and cyst. Results: The overall infection rate was (55.3 percent). The most commonly protozoa was Entamoeba Coli (in 33.6 percent of specimens). Others were Endolimax nana (17.8 percent), Blastocystis hominis (9.2 percent), Giardia lamblia (7.9 percent), Iodamoeba butschlii (2 percent) and Chilomastix mesnili (0.7 percent) respectively. The helminths observed were Enterobius vermicularis (9.1 percent), Hymenolepis nana (1.3 percent), Ascaris lumbricoides (0.7 percent), Trichuris trichiura (0.7 percent) and Trichostrongylus spp(0.7 percent). Discussion: Deficiencies in hygienic practices and poor basic environmental sanitation are the contributing factors in the maintenance of the high prevalence of the intestinal protozoan infections found.

Introduction: In addition to, Carbohyrates, Lipids, Amino acids and vitamins, some of the trace metals are known vital for biological activity. But some of them not only are not necessary, but also they are very toxic and carcinogen. In this research the rate of Mobility and Bioavailability of heavy metals associated with airborne particulates matter such as Zn, Pb, Cd, Cu, Fe, Ni and Cr have been measured. Methods: The sequential extraction has been used for releasing of heavy metales from solid samples as airborne particulates matter on the paper filter samples. Five stages in the sequential extraction procedure developed by Tessier, et al, was first used for extraction and determination of the concentration and percentages of heavy metals which could be released in each stage. In the 1st stage, exchangable metals were released. The sample was extracted with 10 ml of ammonium acetat, pH=7 for 1h. Then the sample was centrifuged at 2000 rpm. The solution of extraction, was analysed for Zn, Pb, Cd, Cu, Fe, Ni and Cr. In the 2nd stage, heavy metals bound to carbonates which were sensitive to pH were extracted. The residue from stage 1, with 10 ml of sodium acetate 1 M the pH was adjusted to 5 with acetic acid. Then the sample was centrifuged as stage 1. In the third stage heavy metals bound to iron and manganese oxides were extracted. The residue from stage 2 was reacted with 10 ml hydroxyl amine hydrochloride at 25% v/v. In the 4th stage metals bound to sulfides and organic compounds were extracted. The residue from stage 3 with 5 ml nitric acid and 5 ml hydrogen peroxide 30% and heated at 85° C. Finally in the 5th stage residual heavy metals were extracted. the residue from fraction 4 with 10 ml nitric acid and 3 ml hydroflouric acid were extracted. The concentrations of Pb and Cd in some fractions of sequential extraction were too low, so, we carried out preconcentration method for these two elements. Results and Discussion: The results show that in different stages, different percentages of the metals were extracted. by the sequential analysis was shown that a considerable amounts of extracted heavy metals such as lead and cadmium during the first and second stages, had a high mobility and bioavailability.

Introduction. Toxaphene is resistant to degration and has been known as persistent bioaccumulator. In oder to understand the persistence and degradation phenomena of toxaphene in soil a series of tests were run. Methods. All experiments for dry and moist soil were conducted with 10 to 20 kg soil samples, contained in plastic tubs. The experiment was carried out in two parts. The five samples studied in each part are described below. Part I: "Dry samples". Soil control I soil amended with 10 percent gin trash/soil amended with 25 percent gin trash/soil amended with 10 percent gin trash and treated with 500 ppm toxaphene and soil treated with 500 ppm toxaphene. These samples were kept dry during the entire experimental period. Part II: "Moist samples". The samples were the same as described in part I, but they were kept moist by addition of water weekly during the experimental period. Periodically twenty grams of soil were analyzed using a gas chromatograph. Results. Chromatograms of dry and moist samples from soil containers (Part I and II) analyzed up to 12 months after initiation of the experiments showed that no toxaphene degradation or dissipation had occurred. GLC profiles of extracts of 12 months soil samples were identical to those of 0 dry samples and almost 100 percent of toxaphene was recovered in all samples after one year regardless of whether samples were dry or moist I amended or not. Discussion. The results suggest that toxaphene dose not undergo degradation in soil" under aerobic condition, so it can be a persistent insecticide in soil under environmental condition.

Introduction: It has been pointed out that the hazard associated with the exposure to tetraethyl lead is Quite different from exposure to inorganic lead compounds, and that the measurment of urinary lead is the best indicator of tetraethy lead absorption and hence its environmental control. Methods: Urine total lead concentrations in service station attendants in Isfahan city after extraction were determined by graphite furnace atonic absorption spectrophotometry. Results: Average total urine lead concentration was (69.75±14.52 mg/l) (range 43 - 105 mg/l). Discussion: All workers has urine total lead levels below the Biological threshold limit value of 150 mg/l. In addition total lead excretions did not correlate with exposure duration and age and also with individual customs such as personal hygiene and smoking habit. In general, on the basis of the present study results and current data it seems that urine total lead is not a sensitive and specific indicator for exposure to tetraethyl lead.

Introduction: Cryptococcus neoformans is an encapsulated yeast like and a principle cause of morbidity and mortality in immunocompromised hosts, especially those with AIDS. At the persent, due to progressive increase in predisposing factors to cryptococcosis and proper therapy, identification of this fungus has become more important than before. The most important sources of infection are contaminated pigeon droppings and soil. Since there are many so called .Pigeon Tower" in Isfahan and it"s suburbs, we decided to isolate and identify C.neoformans from pigeon droppings collected in these towers. It is notable that these pigeon droppings are traditionally used as natural fertilizer. Methods: After preparing suspensions of droppings, we spread them onto the surface of Niger seed agar and L-DOPA containing media. The identification of isolates was established by ureas test, India ink preparation, subculturing on CMA + Tween 80 medium, growth 37°c and assimilation of carbohydrates and nitrate. GCP (Glycine- Cyclohexaamide - Phenol red) medium was used for distinguishing C.neoformans Var. neoformans from C. neoformans Var. gattii. The pathogenicity of the isolates was determined in mice by intracerebral inoculation. Results: c. neoformans was isolated from 11 of 136 samples (8.1 percent). All of them were identified as c. neoformans Var. neoformans. However, five of them (45.5 percent) caused disease in mice. There was no statistically significant relation between the pH of the pigeon dropping and the precence of C.neoformans. Discussion: According to the results, it seems that the actual prevalance of cryptococcosis should be more than the reported cases. Regarding the relative frequency of the yeast in "Pigeon Towers" in Esfahan, as it was shown in this study, clinicians should pay more attention to this organism and its disease, especially in patients with predisposing factors.

Introduction: The goal of this study was to evaluate the relationship between occupational exposure to extremely low frequency (ELF) electromagnetic fields and risk of Hematological changes among workers at High- voltage substations. This is a case - control study. In the present study 79 worker exposed to electromagetic fields (EMFs) were compared to 50 control subjects who were not occupationaly exposed to EMFs. Methods: To measurement the levels of exposure to Lf electric and magnetic fields the strength of electric and magnetic field was determined by Dosimetric method. Worker"s blood samples were collected and analyzed for identification of leukemia and other abnormalities. Questionnaire and physical examination were used to study the effects of ELF fields on worker"s health. Measurements showed a high strength of ELF fields at the work places i.e. Results: Mean value of RBC and Hematocrit decreased significantly among exposed workers compared to controls (P<0.05), but MCV, MCH and MCHC increased. The value of Neutrophiles increased but Lymphocytes decreased significantly among workers considering their workhistory (P<0.05). Discussion: Moreover, tow leukemics (ALL, AML) and ten hypocromic anemias were found. In conclusion study groups are similar in personal characteristics, the difference in RBC, MCV, MCH has to attributed to ELF fields.

Introduction: Population growth and its difficulties is one of the most important health problems in the world especially in developing countries. so the studies in this field are necessary and useful in IRAN. This study was done to find out the workers population specificities and their opinion about family planning programs. Methods: This descriptive study was held in the factories with more than 1000 workers in 1375. nearly 10 percent of the workers were chosen from 7 factories through the systematic random sampling The sample was about 1096 workers. They answered to multiple choise questionnaire during 3 months and the data were analysed by the descriptive statistical methods and also x2 and pierson correlation tests. Results: Most of workers (80 percent) were under 40 years old and 0.5 percent were single and others were married. The illiterates were 6 percent and about 82 percent were studied 8 grades and less. The mean of the number of their children was 3.7 and 33 percent had 5 children or more. The family planning methods were used by them as follows: Tubal ligation and Vasectomy 32 percent, Natural methods 22.3 percent, OCP 19.8 percent, Candom 11.1 percent, IUD 10 percent and Lactation as a method 0.53 percent. About 4.2 percent had used more than one birth control method. Disussion: Result showed that there was a reverse correlation between the age of marriage and number of existing children (P<0.001) and also between the literacy status and the opinion about the number of children (P<0.001) there was relation between the age of the workers and the opinion about the number of children (P<0.01). the reverse correlation between the literacy status and the number of existing children was stables even after the control of the age rariable as a confonder. Study of birth control methods shows that the use of family planning method is different between the groups with different literacy levels.