نشریه پژوهش در پزشکی
سال بیست و هفتم شماره 2 (پیاپی 106، تابستان 1382)

The present study was conducted to determine the efficacy of cryoanalgesia and its complications in patients with post-thoracotomy pain, operated in Masih-Daneshvari hospital in 2001-2.

Sixty patients entered this clinical trial. After thoracotomy, patients were equally distributed in two groups of control and cryoanalgesia. Nerve freezing was carried out for 60 seconds at a temperature of -60 degrees Celsius. Pain was measured by Visual Analogue Scale. Meanwhile, patient's demand for pethidine was recorded till the 7th day. Sensory complications were surveyed through telephone call till the 3rd postoperative month. Pain score, sensory complications and the amount of pethidine administration were compared between the groups.

The mean age (SD) of control and "Cryo" patients were 41.315 and 41.916 years, respectively. In the recovery room, pain score of 2-3 was reported in 63.3% of control subjects, the remaining 36.7% had experienced pain score of 4-5. These figures were 86.7% and 13.3% for the "Cryo" group, respectively (p<0.05). During the following days, pain score was significantly higher in the control subjects. At the 7th day, however, pain score of 0-1 and 2-3 were reported in 13.3 and 86.7% of the control subjects, whereas these figures were 83.3 and 16.7% for the "Cryo" subjects, respectively (p<0.00001). During the first day, pethidine was administered 151.627 mg and 87.548 mg for the control and "Cryo" subjects, respectively (p<0.001). Hypoalgesia, reported in 93.3% of the patients at the end of the first week, disappeared by the end of the 3rd month. Allodynia and dysesthesia was reported in 10% of the subjects at the end of the first week and vanished by the second month.

Cryoanalgesia could safely diminish post thoracotomy pain also, it may eliminate the need for opiates. It has few complications that are soon relieved. We strongly recommend this technique and complementary research in this field.

Fine Needle Aspiration (FNA) of thyroid gland has greater sensitivity as compared to other diagnostic modalities for thyroid nodules. The present study was conducted to compare the sonographic findings of cold thyroid nodules with cytologic changes.

For 219 patients, sonography of thyroid nodules was performed by 7.5MHz probes and the following changes were recorded: echogenicity, calcification, halo formation, distal enhancement, single or multiple nodules, homogenicity, heterogenicity, and cyst formation. Then, FNA was done and results compared.

The study population included 188 females and 37 males with the mean (SD) age of 361 and 4212 years, respectively. FNA had revealed 6 nodules (2.8%) to be malignant, of which, 4 were papillary carcinoma, one was follicular carcinoma and one was Hurthle cell tumor. All except the Hurthle cell tumor had shown decreased nodular echogenicity and irregular limits. None of hyperecho nodules were malignant, however, 3 had shown changes in favor of Hurthle cell tumor. Totally, 21 intermediate lesions including thyroiditis, follicular neoplasm, and Hurthle cell changes have been reported.

Results have revealed that sonographic and cytologic findings in cold thyroid nodules are closely related.

With regard to the relation of exposure to electromagnetic field and disorders in some biological systems and also with respect to the increasing development of these fields, the present study was conducted on 101 employees in high voltage centers in Tehran in 2001 to determine the role of occupation in extremely low frequency (ELF) electromagnetic fields on mental health.

101 individuals who were employed in electromagnetic fields at 50Hz frequency as a result of 230 KV current (case group) and 101 matched controls, (personnel of the administrative section), with no history of working in high voltage centers, entered this historical cohort study. Mental health status was examined using three choice GHQ-28 test utilizing cut off point of 17. Individuals who had received score of >17 were considered "probably unhealthy".

All 202 examined individuals were male and aged over 18 years. Of these, 17% in the control and 32.7% in the case group were revealed to be "probably unhealthy", (P<0.01). The relative risk of working in these fields raised the incidence of mental unhealthiness by 1.9 times (2.1-3.1 in community, p<0.05).

Working in electromagnetic fields at extremely low frequency increases the incidence of mental unhealthiness. In spite of suitable validity and reliability of GHQ-28 test, according to many domestic and foreign studies, researches including clinical interview are recommended. With regard to their high risk job and the importance of mental health for good performance, paying further attention to their mental health, screening and timely treatment of patients is suggested.

The sinoatrial (SA) node is not a uniform tissue in terms of its histology and electrophysiology. The regional differences in action potential configuration are well known, for which the difference on ionic currents underlying the regional differences in electrical activity is the most probable cause. The ionic current "if" is though to play a major role in SA node for pace maker slope of action potential.

This predication was tested in the present study by block of the current on pacemaker activity in the periphery and center of the intact SA node of the rabbit heart by means of 2mM Cs+ for 20 min. First, the action potential of different regions of SA node was recorded by conventional glass microelectrode without Cs+ and nine criteria of action potential configuration were measured. Then, Cs+ was used and again criteria were measured.

In all cases, Cs+ significantly decreased the pacemaker slope (PS) from 201 (control) to 41mV/s (n=8) in peripheral zone, from 324 (control) to 172mV/s (n=7) in transitional zone and from 493 (control to 364mV/s(n=6) in central zone. Meanwhile, 2mM Cs+ also decreased the rate of spontaneous activity by 121%. Instead of rate, the cycle length (CL) was recorded, where the increment on cycle length was reported to be 141%.

"if" current plays a major role in the pacemaker activity in central zone rather than the peripheral zone of intact SA node of the rabbit heart.

The present study was performed to determine the epidemiological characteristics of bacterial neonatal conjunctivitis in three hospitals (Imam Hossein, Resalat and Shahid Akbar Abadi) from 2001 to 2002.

This descriptive study was conducted on all 3140 neonates, born in the aforementioned hospitals, between January 2001 and September 2002. Having obtained a written consent, initial data was collected by asking mothers and referring to the hospital records. Then, for cases with conjunctivitis, samples were obtained by sterile swab from inferior cul de' sac and conjunctival discharges, for direct smears, Gram and Geimsa stains, and also for culturing on blood agar, chocolate agar and thioglycolate media. Additionally, specimens were sent to Health Faculty of Tehran University for chlamydial study by direct immunofluorescent (DIF). On discharge mothers were requested to return with their babies in case of any abnormal ophthalmologic signs. In addition, they were contacted by telephone so that no infant with eye problem should be missed. Finally, data were analyzed by descriptive statistics.

Of 3140 neonates, 1699 (54.1%) were male. 170 neonates had presented with signs of conjunctivitis (5.4%), of these, 82 (48%) had negative culture. The remaining positive cultures were as below: 26(15%) coagulase negative staphylococcus, 23(13.5%) staphylococcus epidermis, 13(8%) E. coli and 10(6%) staphylococcus aureus. Of 170 samples, 10(6%) were positive for Chlamydia, among which, 6 were culture positive for bacteria and 4 were reported as DIF positive.

Regarding the previously reported prevalence of neonatal conjunctivitis (1.64% to 66.5%) the prevalence of 5% in our study shows an acceptable result. Gram positive cocci were the most frequent type of microbial infections. It should be kept in mind that the results of bacterial cultures were negative in 48% of neonates despite positive signs of conjunctivitis. The lower rate of chlamydial neonatal conjunctivitis in our society as compared to western countries may be dues to lower prevalence of sexually transmitted infections in our country.

The purpose of this study was to determine dietary diversity and its relation to dietary adequacy in 10-18 year old adolescents of district 13 of Tehran in 1999-2001.

Dietary intake assessment was undertaken with 2-day 24-hour recall by expert interviewers in 1476 individuals participating in Tehran Lipid and Glucose Study. Having excluded the under and over-reporters, 304 cases, aged 10-18 year old, remained in this study. The dietary diversity score was calculated as part of the pyramid serving database that categorized into 23 broad food groups. Each of the 5 broad food categories received a maximum diversity score of 2 of the 10 possible score points. To be counted as a "consumer" for any of the food group categories, a respondent needed to consume one-half serving, as defined by Food Guide Pyramid quantity criteria, at any time during the 2-day survey period. The nutrient adequacy ratio (NAR) for a given nutrient is the ratio of a subject's intake to the current recommended allowance for the subject's sex and age category. Weight and Height were determined by using a digital electronic weighing scale and tape meter, according to standard protocols of measurements. Then BMI was calculated. Student's t-test was used to compare the means. Those variables with normal distribution were tested by Pearson correlation coefficient and the others were tested by Spearman correlation coefficient.

Dietary diversity score (DDS) was 6.261.08 in this study. The maximum and minimum of diversity was related to fruit (1.460.61) and bread-grain (0.950.27) groups, respectively. Positive and significant correlation was observed between DDS and NAR (r=0.42, P<0.001). Fifty percent of people had DDS of >6, and in them, BMI was higher than those with a DDS of <6, (19.814.07 vs 18.953.30 Kg/m2, P<0.01). There was significant and positive correlation between DDS and most NARs.

Calculation of DDS is an appropriate method to evaluate nutrient intake adequacy. As evidence on diet and health accumulates, it becomes clearer that although individual nutrients are important, they work most effectively in the context of a complex dietary pattern that includes a balance of nutrients from a variety of healthful foods.

Expenses of health facilities have a great impact on their quality. The present study was conducted to determine the expenses of each health facility in rural and urban health care centers in Zanjan province in 2001.

For this descriptive study, 26 minor health care centers in small villages, 6 rural and 5 urban health care centers were selected through randomized sampling. Expenses were determined according to the type of facility, the exact center, and also type of expense. Thus, expenses of usable materials and equipment, specific equipment, drugs, building repairs, vehicles, personnel, and other equipment were all determined in accordance to the population

Expenses of minor health care centers in small villages, rural and urban health care centers were 49, 330, and 44 million Rials, respectively. Personnel expenses were by far the most common type of expenses that comprised 25.7, 21.5, and 31.3% of the aforementioned center's expenses, respectively.

Unfortunately, government has not allocated enough budgets for these health care centers. Meanwhile, paying further attention to the managing aspects of such centers could be helpful to control their expenses. Similar studies are highly recommended in other centers.

An increase in the number of medical schools in Iran has caused a conspicuous escalation in medical research during recent years with the numbers of papers published in Iranian and international biomedical journals increasing annually. In addition to quantitative indices, the evaluation of medical research in Iran requires qualitative parameters. The aim of this study is the qualitative assessment of medical research in Iran regarding, specially, one of its outputs, i.e. papers published in international journals and its comparison to medical research in Pakistan and Egypt.

Papers published in international journals from Iran, Pakistan and Egypt in 1992, 1996, 1999, and 2002 were acquired through searching in PubMed databank. To evaluate the quality of papers, we used the impact factor (IF) of journals publishing the paper. The IF of journals was obtained through the official site of the Institute for Scientific Information (ISI) and the mean IF for these 3 countries was calculated separately.

In 1992, the numbers of indexed papers from Iran, Pakistan and Egypt were 61, 82 and 387, respectively. The mean IF of journals publishing Iranian papers was 1.130.94 in 1992, being 1.252.15 for Pakistan and 1.111.64 for Egypt. In 2002, numbers of indexed papers from Iran, Pakistan and Egypt were 508, 229 and 668, respectively. In the same year, the mean IF of journals publishing Iranian papers was 1.360.98 while it was 1.752.88 for Pakistan and 1.231.57 for Egypt. The obtained results showed 733% quantitative growth of Iranian papers during the 1992-2002 period, which was noticeably higher than Egypt and Pakistan. Also, the mean IF of journals publishing Iranian papers increased from 1.13 to 1.36 during that period.

Upgrading of the IF of journals publishing Iranian papers may indicate enhancement of the quality of those papers, i.e. Iranian research, now enhanced, is eligible for publication in journals with higher Ifs. It must however be kept in mind that on the whole, the mean IF of journals could have increased during that period. The results of this investigation lead us to conclude that medical research in Iran, as compared to Pakistan and Egypt, has definitely progressed quantitatively during the years 1992-2002 and it can also be claimed, at least, that the quality of research has not declined during theses years.

Malaria is one of the most important protozoal infections that afflicts almost 100,000 people with 1% mortality rate in over 100 countries. Unfortunately, effective vaccines have not been developed and most of preventive modalities have focused on carriers, as well as prompt diagnosis and treatment. In Iran, the carrier insect in these provinces has shown resistance to routine pesticides. A. fluviatilis threatens other regions. Thus, along with controlling the carriers, it is necessary to apply other methods such as controlling the larva, and prevention of contract with the parasite. This article presents the application of rapid and accurate techniques of diagnosis such as PCR and new therapeutic modalities.

Crimean-Congo Hemorrhagic Fever (CCHF) is a potentially fatal viral disease. Humans usually acquire the illness through tick bite or from contact with infected blood or other tissues from patients or livestock. CCHF is reported from most parts of Asia, Africa and Europe. This illness was endemic in the eastern provinces of the Caspian sea and has been described in old Iranian medical references. Because of the low incidence, reports on histopathologic findings are relatively few and limited worldwide. In this study we review the necropsy findings of a 24-year old woman with fatal form of CCHF in whom the diagnosis was established with positive viral culture and positive ELISA and RT-PCR in WHO reference laboratory. In liver, hepatocyte necrosis without inflammatory cells in bone marrow, hyperplasia of all three cell lines with myeloid preponderance in lungs, polymorphonuclear infiltration in alveolar spaces and alveolar edema in kidneys, glomerular necrosis, interstitial edema and tubular necrosis, and in brain, generalized edema with degenerative and cystic changes were found. There was no pathologic finding in striated muscle samples with light microscopy. In brief, these findings are compatible with multi-organ failure. Because of many new cases of this disease in recent years in Iran, widespread research for evaluation of histopathological changes is needed in Iranian patients to assist physicians and pathologists towards prompt diagnosis.

Anthrax is a highly dangerous disease that results in death in the absence of prompt diagnosis and treatment. Intestinal form of this disease is rare but fatal. This report presents a 4-year old boy with abdominal pain, vomiting, distension and poor general condition. He was taken to the operating theatre with the diagnosis of peritonitis right hemicolectomy was performed because of ileo-cecal invagination and perforation. Four hours later the patient died of septic shock. His laboratory studies revealed the diagnosis of anthrax. We have discussed the epidemiological aspects of the disease and emphasized the importance of immediate diagnosis and treatment.