Acta Medica Iranica
Volume:42 Issue: 1, Jan-Feb 2004

Neuromelanin (NM) pigment accumulates with age in catecholaminergic neurons in man, and the ventral substantia nigra dopaminergic neurons that are the most vulnerable to degeneration in Parkinson''s disease (PD) contain the greatest amount of this pigment. In vitro data indicate that NM pigment is formed from the excess cytosolic catecholamine that is not accumulated into synaptic vesicles via the vesicular monoamine transporter2 (VMAT2). Using semi-quantitative immunohistochemical methods in human postmortem brain, we sought to examine the relationship between the contents of VMAT2 and NM pigment. The immunostaining intensity (ISI) was measured for VMAT2 in two regions of the midbrain dopaminergic cell complex. The ISI of the cells was related to the density of NM pigment within the cells. We also measured the ISI for tyrosine hydroxylase (TH) and examined the noradrenergic neurons in the locus coeruleus (LC). In brains 22-65 years of age: 1) ventral substantia nigra neurons had the lowest VMAT2 ISI of all neurons in the midbrain cell complex, whereas over 2-fold higher levels are found in most ventral tegmental area neurons; 2) there was an inverse relationship between VMAT2 ISI and neuromelanin pigment in the midbrain dompaminergic neurons; 3) neurons with the highest VMAT2 ISI resided in the LC; 4) neurons with high VMAT2 ISI also had high TH ISI; and 5) in the newborn brain, which has not yet accumulated neuromelanin pigment in the aminergic neurons, the regional distribution of VMAT2 and TH-ISI was similar to that found in the adult brain. These data support the hypothesis that among the midbrain dopaminergic neurons, the ventral substantia nigra dopamine neurons accumulate the highest levels of NM pigment because they have the lowest levels of VMAT2, which thereby renders them especially vulnerable to degeneration in PD.

Valproic acid is one of the main antiepileptic drugs. There is an increased risk of neural tube defects and axial skeletal malformations among infants born to women who had received valproic acid. There is a hypothesis that one biochemical abnormality underlying the teratogenicity of valproic acid is a drug-induced reduction in maternal plasma zinc. In the present experimental study mated rats were divided into four groups of 8 animals each [control, valproic acid (VPA), valproic acid + zinc (VPA+ Zn) and zinc (Zn) groups]. The VPA group received 300 mg/kg valproic acid, daily.The control group received an equal volume of 0.9% NaCl. The VPA+ Zn group received 300 mg/kg VPA and 30 mg/kg zinc sulfate and the Zn group received 30 mg/kg zinc sulfate, daily. Valproic acid, NaCl, and Zn were administered intraperitonealy from day 6 through day 15 of gestation. On day 16, six rats of each group were authanized and the other rats were scarified on gestational day (GD) 20 to evaluate the skeletal system among the elder fetuses. Blood was drawn to determine plasma zinc. The data were analyzed by using analysis of variance (Kruskal -Wallis test). The zinc concentration in the plasma of rats treated with valproic acid was significantly lower than those of the other groups on 16 GD (P=0.004). Some anomalies such as hydrocephaly, spina bifida, hemivertebrate, and rib malformations were seen in VPA treated group. Low percentage of rib anomalies and spina bifida were observed in the VPA+ Zn treated group while no skeletal anomalies were seen in Zn and control groups. The results from the present experiment support the hypothesis that one of the biochemical abnormalities causing the teratogenicity of VPA is a drug–induced maternal plasma zinc deficiency, and possibly, it may also result in reduction of embryonic Zn.

Garlic, an antioxidant plant, can react with amino groups of proteins to form Schiff bases. As diabetes leads to glycation of various proteins and this in turn has some effects on the structure of proteins and biochemical activity of them, the inhibition of this process seems very vital. For several years researchers in this field have done their best to recognize the antidiabetic compounds. The aim of this study is to determine the effects of garlic on albumin glycation in vitro.In the presence of various concentrations of garlic, albumin was glycated and evaluated using TBA (thio-barbituric acid) method. The results showed that garlic has a statistically significant (P<0.05) effect in inhibiting or decreasing the reaction of albumin glycation. The findings of this research shows that garlic probably inhibits the reaction of glycation and decreases complications occurring in diabetes.

Coagulase-positive and coagulase negative, methicillin-resistant staphylococci are major causes of serious nosocomial infections and it is very important to have a reliable test to detect these bacteria. A multiplex polymerase chain reaction (mPCR) was used on 100 clinical samples for simultaneous amplification of the universal bacterial, mec-A encoding the penicillin binding protein 2a, which is associated with staphylococcal methicillin resistance and TEM-1 encoding the β-lactamase, which accounts for the majority of all cases of the plasmid β-lactamase resistance worldwide. Out of 100 wound swabs tested, 99% with universal primers, 26% with TEM-1 primers and 6% with mec-A primers were positive. Dot blot Digoxigenin hybridization on the 30 samples was carried out to confirm identified bacteria with specific bacterial probes. Out of 100 wound swabs, 38% were positive with Staphylococcus aureus probe, 23% were positive with enteric bacteria probe, 7% were positive with Streptococcus agalactia probe and 1% were positive with Haemophilus influenza probe. The mPCR method used in this study, was designed to be incorporated into the workflow of the clinical microbiology laboratory and allows for the identification of intrinsic resistance in a timely and reliable manner.

Despite reduction in infant mortality rate, neonatal mortality rate particularly during the first 24 hours of life is still high in developing countries. A cross-sectional study was performed to determine neonatal mortality prevalence during the first 24 hours of life (F24NM) and its probable risk factors. Data collection were performed by a structured form containing maternal and neonatal characters. Newborns'' mothers underwent an interview about their age, gravidity, parity, history of chronic illnesses, history of reproduction (including stillbirth, abortion and infertility) and conditions during recent pregnancy (including vaginal bleeding, multiple pregnancy, gestational illnesses and duration of premature rupture of membranes [PROM]). Neonatal characters contained sex, gestational age (GA), birth weight (BW), first minute Apgar score (FMAPG), visible congenital malformation, meconium stained amniotic fluid, nonperipheral cyanosis, hydrops fetalis, type of first respiration and neonatal death during first 24 hours of life which were obtained from medical records. A total of 1220 live-born neonates were studied during autumn 1999 at four teaching general hospitals in south of Tehran. The prevalence of F24NM was 22/1000. There were 48.42% males and 51.58% females. Of twenty seven first 24 hours neonatal deaths 23 cases (85.19%) were delivered prematurely or were low birth weight (LBW). Eighty nine percent of cases had abnormal FMAPG or cried for the first time only after resuscitation. Prolonged premature rupture of membranes and positive history of stillbirth (SB) was found in 29.63% and 18.52% of the mothers, respectively. FMAPG less than 4 (odds ratio [OR] 46.87, 95% confidence interval [CI] 3.97-55.85), history of SB (OR 12.48, CI 3.45-45.12), visible congenital malformation(s) (OR 12.44, CI2.06-75.00), PROM longer than 24 hours (OR 9.77, CI 3.64-26.19), birth weight less than 1500g(OR 8.45, CI 1.22-58.38), vaginal bleeding during recent pregnancy (OR 6.61, CI 1.93-22.60) and nonperipheral cyanosis(OR 6.55, CI 1.76-24.30) were significant risk factors for the F24NM by multiple logistic regression. According to this study, it seems offering adequate prenatal care particularly in high risk pregnancies and on time management of high risk labors or deliveries might reduce the number of neonatal deaths during the first 24 hours of life.

The exact role of the epithelial lining of the trachea in modulating the bronchial tone is controversial. The present study was an attempt to verify the role of both prostaglandins and mast cells in the acute phase of acid inspiration in rat. Four groups (n = 6) of N. Mari rats were employed. The first group was used as placebo control, and normal saline was injected. To the second group hydrochloric acid (25 µl) with pH of 1.3 was injected into the trachea through the criothyroid membrane. The third and fourth groups were pretreated for three consecutive days either with indomethacin (10 mg/Kg) or nebulized sodium cromoglycate (20 mg/Kg), 1 hour prior to installation of the acid. Three minutes after instillation of acid, the trachea was removed. The tracheal spirals were prepared and immediately suspended in an organ bath containing Tyrode’s solution. Dose response curves to acetylcholine (10-9 to 10-3M) were constructed. The results showed that the responses to acetylcholine in the acid treated trachea were significantly (P<0.01) reduced compared with the control saline treated trachea due to acute acid-induced tracheal contraction. Incubation with atropine, induced reduction of baseline tension and reversed the responses to acetylcholine. Both indomethacin and sodium cromoglycate, reversed the responses to acetylcholine and were in similar range as the control trachea. In conclusion, it seems that both prostaglandins and mast cells are important mediators in the acute phase of airway smooth muscle contraction following instillation of acid.

Vascularization of the follicle may play a role in its maturation and aspirin seems to increase this vascularization.In this investigation we have studied the effects of low-dose aspirin on ovarian and uterine response, implantation and pregnancy rates in patients undergoing intracytoplasmic sperm injection (ICSI). This prospective semirandomized, double-blind, placebo-controlled study was undertaken in Mirza Kochek Khan IVF center. Forty four infertile patients who were undergoing ICSI cycle were studied and they were divided in two groups. The mean age of patients and distribution of the cause of infertility in two groups were similar. In the treatment group, 22 patients underwent controlled ovarian hyperstimulation and received a daily dose of 100 mg aspirin. In the control group 22 patients underwent controlled ovarian hyperstimulation in association with placebo. Number of follicles ≥ 15mm in diameter, number of oocytes retrieved, endometrial thickness, cancellation rate, number of transferred embryos and implantation and pregnancy rates were analyzed in two groups.There was no statistically significant difference between the treatment and control groups for each of the above variables (P >0.05). This study showed that low dose aspirin therapy has no added effect to ovarian and uterine response, implantation and pregnancy rates in ICSI patients.Further studies are recommended for confirmation of our results.

The prevalence of food allergy is different in various nations. The identification of the most common food allergens is a priority in any population to provide effective preventive and curative measures. The aim of this study is to determine the most common food allergens in Iranian children. One hundred and ninety children with skin, respiratory or gastrointestinal symptoms, which were thought to be due to food allergy, were studied. Total serum IgE and eosinophil count tests were measured in all patients. Allergy to 25 food allergens was determined according to the patient’s history, skin prick tests, radioallergosorbent test (RAST) and open food challenge tests. The most common food allergens were cow’s milk, tomato, egg white, egg yolk, beef and almond, in decreasing order of frequency. The order of common food allergens in this study was different from other reports that might be due to the different food habits and/or ethnic diversities.

Bacteremia is an important infectious disease which may lead to death. Common bacteria and pattern of antibiotic resistance in different communities are different and understanding these differences is important. In the present study, relative frequency and pattern of drug resistance have been examined in bacteria isolated from blood cultures in Razi Hospital laboratory. The method of the study was descriptive. Data collection was carried out retrospectively. Total sample consisted of 311 positive blood cultures from 1999 to 2001. Variables under study were bacterial strains, antibiotics examined in antibiogram, microbial resistance, and patients'' age and sex. The most common isolated bacteria were Salmonella typhi (22.2%) and the least common ones were Citrobacter (1.6%). The highest antibiotic resistance was seen against amoxicillin (88.4%). The proportion of males to females was1: 1/1 and the most common age group was 15-44 (47.3%). Common bacteria and pattern of antibiotic resistance were different in some areas and this subject requires further studies in the future.

Determination of pre-hospital delay time of patients with acute myocardial infarction and seeking ways of speeding up the time for reperfusion is an important factor to lower mortality in these patients. This is a cross-sectional study to determine pre-hospital delay time, its components, and related causes and conditions, obtained in 375 patients with prolonged chest pain referred to four hospitals of Tehran University of Medical Sciences. Means of transport to hospital, reasons of ambulance disuse, decision time by the patient and finally the entire time of pre-hospital delay were specified. Suspected factors related to delays of more than 2 and 6 h were scrutinized with chi-square test. Rate of ambulance utility (18.9%) directly correlated with age of patients (P<0.05). Principal motives to disuse ambulance insuccession were unrememberance (33.7%), access to private vehicle (32.8%) and supposition of sufficient speed of personal reference (18.9%). Pre-hospital delay time was 8.1 ± 9.1 h (mean ± SD) in whole patients and 7.6 ± 9.1 h in those with acute myocardial infarction. Delays of more than 2 and 6 hoccurred in 67.5% and 33.6% of patients, respectively. Decision time constitute three fourth of whole pre-hospital delay and was correlated with female gender, older age, history of diabetes, lower level of literacy and nocturnal onset of symptoms. In conclusion, a significant number of patients with acute myocardial infarction have pre-hospital delay of more than 2 and even 6 h, when golden time for thrombolytic therapy has already been elapsed.

Consensus regarding management of pyogenic liver abscess (PLA) among children is yet to emerge, and documentation on these subjects is scanty. Eighteen cases of PLA admitted at Children’s Medical Center in Tehran, Iran, over a 15 year period were analyzed to document the clinical profile and to evaluate the management of PLA among children. Records of all patients were reviewed for presenting signs and symptoms, any associated condition, investigative results, management, and follow–up findings. The overall rate of PLA was 48.9 per 100,000 pediatric admissions in our hospital. Moderate to severe malnutrition was present in five (27.8%) and ascariasis in seven (38.9%) children. Common presentations were fever (100%), abdominal pain (76.9%), and tender hepatomegaly (83.3%). Fourteen patients (77.8%) had solitary liver abscess. Organism was isolated in 11 cases (63.3%), and staphylococcus aureus was the commonest isolate (66.7%).Twelve cases were managed conservatively with antibiotics alone, of these only two (16.7%) required drainage later. Percutaneous aspiration was also undertaken in four additional (22.2%) cases and open drainage in two (11.1%), at presentation. The overall mortality rate was 11.1%. Time taken for complete resolution ranged from 10 to 40 days. Altogether, we conclude that any child presenting with fever, abdominal pain, and tender hepatomegaly should be subjected to ultrasound scan for early detection of PLA. It seems that a combination of cloxacillin and gentamicin or a third generation cephalosporine and gentamicin, especially in infants, is a satistactory initial coverage. Therapeutic drainage is not an obligation in all cases of PLA. When required, percutaneous needle aspiration is safe and effective. Resolution and significant reduction in mortality has been made possible by early detection and appropriate antibiotic therapy.

Visceral leishmaniasis (VL) is usually treated with pentavalent antimonial drugs given alone or in combination with other drugs. The efficacy of these treatments is diminishing, however, and development of alternative treatments has been recommended.We studied 13 patients with leishmaniasis who were unresponsive to meglumine antimonate, at a dose of 20 mg/kg body weight/per day given for 30 days. These patients were treated with daily regimen of amphotericin B, starting with an escalating dose of 0.1mg/kg body weight per day until a day dose of 1.5 mg/kg was reached for a period of 4 weeks. All 13 patients using the treatment regimen were cured; no patient relapsed in one year of follow-up. Treatment of visceral leishmaniasis (kala-azar) with the daily regimen of amphotericin B at a dose of 1.5 mg/kg body weight was effective.

Febrile seizure is the most common type of convulsion yet described in man. It is a convulsive event mainly occurring in children between the ages of 6 to 60 months and is not accompanied by any type of electrolyte imbalance and CNS infections, which are very difficult to be ruled out in infancy. To determine the frequency of cerebrospinal fluid (CSF) pleocytosis in infants under the age of eighteen months with febrile seizure who routinely undergo lumbar puncture, we studied 159 cases (from 3 to 18 months of age, mean of 11, SD of 4 months), referred to Takhti Children Hospital from September 1995 to September 1996 because of Febrile Seizures. There were only 5 patients (3.1%) with pleocytosis in our case series. Significant correlation was found between pleocytosis and high erythrocyte sedimentation rates (CI=99%, Chi square=5.94) in our patients. There was also a positive correlation between pleocytosis and the duration between the beginning of fever and occurrence of seizure (CI=98%, Chi square=7.58). We concluded that there was little risk for our patients to have CSF pleocytosis. We also strongly recommend further investigations to exam the relationship of various signs and symptoms with meningitis in infants with seizure and fever, preferably in the form of likelihood ratios. It is noteworthy to emphasize that performing a lumbar puncture in any infant less than 18 months of age is practically rational until more precise and specific indications emerge from further such welldesigned studies in the future.

Duplications of gastrointestinal tract are congenital anomalies found in about 0.2% of all children. These include the rare gastric duplication. We present such a cyst in a 14 years old girl with gastric outlet obstruction. She was found to have a noncommunicating antral duplication cyst. The cyst was managed by cystectomy and marsupialization. Microscopically the duplication cyst contained a mucosal, submucosal and muscularis layers. There was no evidence of ulceration or malignant cells. Her recovery was smooth. Etiology, presentation and management of duplication cyst of the stomach is discussed together with a review of literature.

The only available vaccine against tuberculosis is BCG which has been found to protect children against disseminated tuberculosis and tuberculous meningitis. BCG is one of the safest vaccines being used, and osteitis is a rare complication of it. During a period of eight years, we had eleven cases of osteitis occuring in infants following BCG vaccination. Eight cases were female. Defect in immune response was not found in any of the patients and all got cured with simple curretage of the lesion and appropriate drug therapy without any sequelae.