Tehran University Medical Journal

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Background: The cause of osteoporosis is multifactorial and many dietary factors are important in the prevention of this disease. Antioxidants as free radical scavengers may influence osteoporosis by reducing the effects of oxidative stress that may be associated with bone loss. Vitamin E is an important antioxidant that protects polyunsaturated fatty acids (PUFA) in cell membranes from oxidation. There are only two studies regarding vitamin E plasma levels in subjects suffering from osteoporosis. The purpose of this study was to investigate the association between plasma vitamin E levels and bone mineral density (BMD) in Iranian patients.
Methods: Subjects were consecutively recruited between May and September 2005 from among a total of approximately 1000 people referred for instrumental screening for osteoporosis to the Jami Clinic in Tehran. Inclusion criteria for the study group were: a femoral neck T-score of -1 or less, osteopenia, severe osteopenia and osteoporosis. A total of 137 subjects were enrolled. According to their femoral and spinal BMD scores, 54 persons were selected as a control group. The control group consisted of subjects with a femoral neck T-score and spine T-score of -1 or more. In selecting the case group, only the femoral BMD score was used. Plasma vitamin E was measured, after extraction with methanol, by HPLC with UV detection at 280 nm. Methanol, deionized water and butanol (90:4:6) was used as a mobile phase with a C8 column. The flow rate was 1.0 ml. min-1 and the acetate ester of vitamin E was used as an internal standard.
Results: The results show no significant difference in plasma vitamin E between the control and case groups, however linear regression analysis does reveal a significant difference between the T-score and plasma vitamin E.
Conclusion: Deceleration Femoral bone Density during osteoporosis will be Accelerated with Decrease of Vitamin E Antioxidant level.

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Background: Until a few decades ago, celiac disease was considered to be essentially a disease of European people and to be very rare in Middle Eastern countries. During the last two decades, having met the criteria for the WHO general screening, the advent and application of novel serological assays used to screen for celiac disease and the use of endoscopic small bowel biopsy have led to increasing numbers of diagnoses of celiac disease in western countries. With this new data, our knowledge on both the clinical pattern and epidemiology of celiac disease has increased, and is now known to be a relatively common autoimmune disorder. Studies performed in different parts of the developing world have shown that the prevalence of celiac disease in this area is similar to or even higher than that in western countries. In fact, celiac disease is known to be the most common form of chronic diarrhea in Iran. However, contrary to common belief, celiac disease is more than a pure digestive alteration. It is a protean systemic disease, and, with a 95 percent genetic predisposition, has a myriad of symptoms including gastrointestinal, dermatological, dental, neurological and behavioral that can occur at a variety of ages. Monosymptomatic, oligosymptomatic, atypical (without gastrointestinal symptoms), silent and latent forms of celiac disease have been identified. In this study we review the epidemiology of celiac disease based on the studies performed in Iran and discuss its pathogenesis, the role of antibodies in the diagnosis of celiac disease and the importance of its diagnosis and treatment in Iran.

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Background: It has been shown that five deficits of the proprioceptive system and poor motor skills are associated with chronic low back pain (CLBP). However, the exact mechanism is unknown. The objectives of this study were to assess the dynamic postural balance behavior of CLBP patients, as well as the effects of a specific exercise therapy for the treatment of CLBP and related postural imbalances.
Methods: Sixteen females with CLBP and 30 healthy females all between 20 and 40 years of age, of similar height and weight, voluntarily participated in this study. Patients underwent a three-month therapeutic exercise program. The disability and back pain of the patients were measured using the Oswestry and Quebec questionnaires, respectively. A dynamic stability platform system (Biodex) was used to evaluate the postural imbalances in both groups. All measurements of the experimental group were repeated after the therapy.
Results: Overall deviation of center of gravity (COG) from COBOS in patients and controls were 3 (±0.3) and 1.3 (±0.2), respectively. Thus, postural imbalances were 2.3 times greater in the patients than those of the controls. After the treatment, the disability and pain of the patients were diminished by 53% and 58%, respectively. Furthermore, with the improvement of the patients COG deviation, both groups had similar posture.
Conclusions: The postural orientation of CLBP patients was significantly improved by the therapeutic exercise program. The applied exercise therapy significantly reduced both the pain and the disability of the patients. Based on these conclusions, we recommend that postural correction be included in regular therapeutic exercise programs.

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Background: Opiate-induced addiction is a main social problem in Iran. As treatment of this problem is a health priority among the medical community, studies on this topic are very crucial. The exact mechanism of dependence on opiates and their withdrawal syndrome remain unclear. It seems that dopaminergic system and locus coeruleus (LC) have an important role in the expression of somatic signs during opioids withdrawal. The LC has been shown to contain significant levels of dopamine (DA). In the present study, the effects of different D2 dopaminergic receptor agonist and antagonist administration in the LC on withdrawal sign expression in morphine dependence is investigated in rats.
Methods: Adult male Wistar rats, weighing 220–280 g were divided into eight groups (n=8). Two cannulae were stereotaxically implanted bilaterally into the LC of each rat. After a one-week recovery, seven groups were rendered dependent on morphine by subcutaneous injection during a seven-day period. Non-dependent control animals received saline according to the same protocol. Animals received bilateral intra-LC injections of saline (1 μg/site) and quinpirole (0.1, 0.3 and 0.5 μg/site, a D2 agonist) 15 min and sulpiride (5, 15 and 30 μg/site, a D2 antagonist) 30 min prior to naloxone injection about 24 hours after the last dose of morphine or saline according to their respective group. To calculate the total withdrawal score, as an index of withdrawal syndrome, 20 different withdrawal signs were assessed and the scores of the intensity of these withdrawal signs were added.
Results: Total withdrawal scores were significantly decreased by quinpirole (0.1µg/site) and sulpiride (15 and 30 µg/site).
Conclusion: The D2 dopaminergic system in the LC may be involved in the morphine-induced dependency in rats. Further studies are needed to define the mechanism of this dependency in order to improve methods for the rehabilitation of addicts.

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Background: Propofol and Thiopental are intravenous anesthetics having relatively different hemodynamic influences and adverse effects. In addition, there is significant pain on intravenous injection of propofol. This study was performed to examine the effects of Propofol-Thiopental admixture on hemodynamic variables, pain on injection and hypnotic dose at the time of induction of general anesthesia.
Methods: One hundred and twenty-five ASA I or II patients scheduled for elective surgery were randomized into four groups for induction of anesthesia in a double-blinded manner. With an original concentration of Propofol of 1% and that of Thiopental of 2.5%, we used these drugs in each group as follows: group P100: Propofol alone group P75: ¾ Propofol and ¼ thiopental (volume/volume) group P50: ½ Propofol and ½ thiopental group T100: Thiopental alone (control group). Hemodynamic variables (before and after induction), score of pain on injection and hypnotic doses were recorded and statistically analyzed.
Results: Admixture of Thiopental and Propofol reduces the injection pain of Propofol, as admixtures P75 and P50 were significantly less painful on injection than P100. Induction of hypnosis was significantly more rapid in group T100 than in groups P100 and P75. The interaction of Propofol and Thiopental with regard to their hypnotic effect is additive. Therefore a reduction in the dose of one was compensated by proportional increase in the dose of the other drug for a hypnotic effect. After anesthesia induction, systolic and diastolic blood pressures were significantly lower in group P100 than in groups P75, P50 and T100. The heart rate after laryngoscopy and tracheal intubation was significantly lower in group P100 than in groups P50 and T100.
Conclusion: Propofol-Thiopental admixture causes minimal pain on injection for intravenous induction of anesthesia with modified hemodynamic effects in comparison with each drug when used separately.

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Background: Impairment in the function of the lower urinary tract can be the cause of recurrent urinary tract infections (UTI) and vesico-ureteral reflux (VUR) in children. The purpose of our research was to evaluate the frequency of occurrence of bladder instability in children with UTI.

Methods: The research involved 133 children (11 boys, 122 girls), ranging in age from seven months to 14 years. Group A consisted of 78 children with a history of recurrent UTI, while Group B included 55 children with recurrent UTI and VUR. Urodynamic tests (cystometry) were performed on all the children.

Results: Abnormal functioning of the lower urinary tract was found in 98 children (73.1%) from Group A and 41 children (78.8%) from Group B. The most common dysfunction was detrusor-sphincter dyssynergia (DSD), which was found in 54% of all subjects, 46.2% of patients in Group A and 60% of patients in Group B (p<0.05). Unstable bladder was found in 42 (33%) children with no significant difference between the two groups. In 17 children (12.6%) DSD was accompanied by bladder instability. In both groups about 20% of the children did not present with symptoms indicative of urination dysfunction, where as 80% reported various symptoms, of which the most common were constipation and urinary urgency. In half of the children from Group A and one-fourth of the children from Group B there were several co-occurring symptoms: frequency, urgency, intermittent voiding, incontinence, dribbling and retention, and constipation.

Conclusions: The most common disturbance of lower urinary tract function in these children with recurrent UTI was DSD, which occurred more often in children with VUR.

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Background: Hyperhomocysteinemia is an independent risk factor for cardiovascular diseases. The frequency of hyperhomocysteinemia is higher in hemodialysis (HD) patients than the general population. The objective of this study is to assess the efficacy of high-dose folic acid supplementation with and without vitamin B12 on lowering plasma total homocysteine (tHcy) concentrations in HD patients.

Methods: Thirty-six HD patients at Imam Hossein Hospital, Tehran, Iran, who had been given folic acid supplements (5 mg/d) for at least 3 months before, were enrolled in this clinical trial. Subjects were also checked for other inclusion and exclusion criteria. The subjects were divided randomly into four groups and underwent two months of supplementation as follows: 5 mg/d oral folic acid + placebo in group one, 5 mg/d oral folic acid + vitamin B12 (1 mg/d orally) in group two, 15 mg/d oral folic acid + placebo in group three and 15 mg/d oral folic acid + vitamin B12 (1 mg/d orally) in group four. Concentrations of plasma tHcy and serum folic acid and vitamin B12 were measured at baseline and after the supplementation period. Dietary intake of patients was also determined during the supplementation period.

Results: Of the folic acid supplemented patients, 27.8% had normal levels of tHcy at baseline and 72.2% had hyperhomocysteinemia. After the supplementation period, plasma tHcy increased by 1.35% in group one and decreased by 6.99%, 14.54% and 30.09% in groups two, three and four respectively. Changes in plasma tHcy and serum vitamin B12 were only significant in group four however, no significant changes were seen for serum folic acid. The percentage of subjects reaching normal levels of plasma tHcy was 5.6 fold higher in group four than in the reference group.

Conclusions: Supplementation with 15 mg/d folic acid together with 1 mg/d oral vitamin B12 is more effective in reducing tHcy levels in HD patients.

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Background: Remifentanil is known to produce side-effects of hypotension and bradycardia. In this study, we examine the effect of low-dose ketamine infusion on the heart rate and blood pressure of patients anesthetized with remifentanil.

Methods: In a randomized clinical trial, 54 patients aged 20-50 years old, with ASA physical status Ι, were studied in two groups (n=27), Ketamine- Remifentanil (K-R group) and Placebo- Remifentanil (P-R group). Exclusion criteria were ASA physical status >1, gastroesophageal reflux, tachycardia, bradycardia, systemic diseases, use of antihypertensive drugs, difficult intubations, risk of aspiration and contraindications of ketamine. Remifentanil was started at a rate of 0.5 µg. kg^-1. min^-1 and anesthesia was induced with thiopental sodium 2 mg.kg^-1. Maintenance of anesthesia included halothane and nitrous oxide/oxygen mixture. Remifentanil infusion was continued in both groups at a rate of 0.5 µg.kg^-1.min^-1. In the K-R group, ketamine was started with an infusion rate of 10 µg.kg^-1. min^-1, 10 minutes after intubation, while in the P-R group, normal saline was started with the same dose of remifentanil. Heart rate, systolic, diastolic and mean arterial blood pressure were measured and compared at 1, 3, 5, 10, 15, 20, 25 and 30 minutes.

Results: No significant differences were found between basic patient characteristics of mean of age, sex, weight, systolic, diastolic and mean arterial blood pressure and heart rate (p>0.2) in the two groups. However, the rate of systolic, diastolic and mean arterial blood pressure changes in the P-R group was significantly greater than that of the K-R group (p<0.006). Heart rate changes were similar between the two groups (p=0.6). Incident of severe hypotension (a decrease of more than 25% of the basic value) was less in the K-R group than that of the P-R group (11% vs. 89% p=0.000).

Conclusion: Low-dose ketamine infusion modulates the effect of remifentanil-induced hypotension and provides better hemodynamic stability during general anesthesia.

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Background: Joint trauma and injury are the most common causes of dynamic instability. Dynamic instability has a great effect on the lumbar spine, due to its three-dimensional motions. The greatest amounts of compression and shearing force are imposed at the points of maximum torque and velocity. The changes in these phase angles upon bearing various loads can cause some pathologic conditions. In this study, we examined the phase angle at maximum torque and velocity in the three planes of movement and then estimated their displacement upon external loads.

Methods: Using the B200 isoinertial dynamometer, 13 subjects were tested in three stages as follows: 1) Familiarization with tests and apparatus. 2) Warm-up and three maximum isometric tests, with a rest interval between each test, in the three axes of lumbar motion including: flexion/extension, rotation to right/left, lateral flexion to the right/left. 3) Five dynamic tests in these three axes of motion without load, with 25% maximum voluntary torque, and with 50% maximum voluntary torque. Special software was used to analyze the raw data and detect the occurrence of maximum torque and velocity in the dynamic range of motion at each of the three axes.     

Results: When the load was increased, the maximum dynamic torque in each of the three axes increased (P<0.05). The increase in load shifted the phase angles toward the maximum torque and velocity (P<0.05), with a positive correlation between changes in torque and velocity phase angles (P<0.05).

Conclusions: Rather than being a function of the biomechanical pattern, the changes in maximum torque and velocity of the phase angles following an increase in motion resistance to the outer range of the three axes are actually a control behavior in the motion processing system in dynamic movement.

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Background: Immediately after Comprehensive Medical Basic Sciences Examination (CMBSE), the secretariat of the Medical Basic Sciences Education Council (MBSEC) proceeds to rank medical universities according to the students’ scores both in individual academic subjects such as biochemistry, English and in all subjects put together. This study believes that the method used in ranking the universities according to the students’ English scores is not a proper method and thus doesn’t provide accurate results.
Methods: Seven of the major and smaller universities were selected. The language scores of all the students admitted to the medical schools of these universities during 3 academic years of 1378 to 1381 (2426 students in all) in both CMBSE and National university Entrance Examination (NUEE) were obtained. The language scores of each students in NUEE and CMBSE were matched.
Results: A significant correlation (max. R=69%, P<0.004 to min. R=27%, P<0.045) was observed between these two grades in all universities studied. Moreover despite the secretariat’s decision to calculate the scores and rank the universities in two separate groups of major and small universities, in some CMBSEs certain smaller universities were ranked in the group of major ones and in some others vice versa.
Conclusions: This has impaired the university ranking in the subject of English language. This study proposes two different ranking methods, that eliminate the present drawback in university ranking according to their student’s English scores.

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Background: The risk of atherosclerosis and cancer is high in hemodialysis (HD) patients. There is evidence that HD causes oxidative stress. However, the causative factors of oxidative stress are unknown. It has been suggested that HD imposes an additional oxidative stress on patients with chronic renal failure by activation of granulocytes on dialyzer membranes resulting in an imbalance between oxidants and antioxidants. In this regard, a number of reports, either measuring specific analytes or enzymes, or estimating the total antioxidant activity of the plasma have given contradictory and inconclusive results. To investigate the oxidative stress status in Iranian HD patients, in this study, we evaluated GSH and FRAP levels along with Ca and pH in the blood of these patients.

Methods: Along with 20 healthy age and gender matched control subjects, 24 patients underwent dialysis, three times per week, for four hours in each session. Before and after dialysis, blood was taken for biochemical and liver function tests and to evaluate oxidative stress markers and measure Ca and pH levels.

Results: There was a significant decrease in FRAP and GSH levels after dialysis compared to those before treatment. Dialysis caused an increase in pH and Ca levels compared to levels in control subjects after dialysis.

Conclusion: In general, before dialysis, there is a balance between oxidants and antioxidants however, due to higher levels of oxidants as well as the possible binding of antioxidants to the dialyzer membrane during dialysis, an imbalance occurs. The instability in the balance of oxidants and antioxidants may be the major cause of cellular oxidative damage found in HD patients. This study indicates that there is a significant level of oxidative stress in renal chronic patients and this stress is augmented by dialysis. Antioxidant therapy should be considered in these patients.

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Background: Childhood nephrotic syndrome is frequently characterized by a relapsing course. Due to their adverse effects, the use of corticosteroids for the management of frequently relapsing nephrotic syndrome is limited. Levamisole, a steroid sparing agent, has been found to have low toxicity. This study was conducted to evaluate the efficacy of levamisole in steroid-sensitive nephrotic syndrome (SDNS). 

Methods: In this retrospective study from January 1988 to September 2006, we included data from 305 pediatric SDNS patients at the Children's Medical Center clinics in Tehran, Iran. Nephrotic syndrome was diagnosed using classic criteria. None of the patients had any signs or symptoms of secondary causes of nephrotic syndrome. All had received prednisolone 60 mg/m²/day. After remission, prednisolone administration was reduced to every other day and the steroid was tapered over the next three months. With every recurrence, prednisolone was prescribed with the same dosage, but after remission it was continued at a lower dosage for another six months or longer if there was risk of recurrence. Levamisole was administered to all patients at a dose of 2 mg/kg every other day.         

Results: Patients ranged in age from 1 to 20 years (mean±SD: 4.84 ±3.1) and 70.8% were male. At the last follow up, 84 (27.5%) were in remission, while 220 (72.1%) patients had relapsed or needed a low dose of steroid. Levamisole was effective in reducing the prednisolone dosage and long-term remission in 68 (22.3%) and 90 (29.5%) cases, respectively. A comparison of before vs. after levamisole treatment revealed a had significant decrease in the number of relapses (2.05±0.88 vs. 1.1±1.23 P<0.0001) and the prednisolone dosage (0.74±0.39 vs. 0.32±0.38 mg/kg/day P<0.0001). Only one patient developed levamisole-induced neutropenia.

Conclusions: In childhood steroid-dependent nephrotic syndrome, levamisole is an efficacious, safe initial therapy in maintaining remission while decreasing steroid dose, in addition to reducing the rate of relapse.

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Background: Premedication is widely used in pediatric anesthesia to reduce emotional trauma and ensure smooth induction. The rectal route is one of the most commonly accepted means of drug administration. The aim of our study was to investigate and compare the efficacy of rectally administered midazolam versus that of ketamine as a premedication in pediatric patients.

Methods: We performed a prospective randomized double-blinded clinical trial in 64 children, 1 to 10 years of age, randomly allocated into two groups. The midazolam group received 0.5 mg/kg rectal midazolam and the ketamine group received 5 mg/kg rectal ketamine. The preoperative sedation scores were evaluated on a three-point scale. The anxiolysis and mask acceptance scores were evaluated separately on a four-point scale, with ease of parental separation, based on the presence or lack of crying, evaluated on a two-point scale.

Results: Neither medication showed acceptable sedation (>75%), with no significant difference in sedation score between the two groups (P=0.725). Anxiolysis and mask acceptance using either midazolam or ketamine were acceptable, with  midazolam performing significantly better than ketamine (P=0.00 and P=0.042, respectively). Ease of parental separation was seen in both groups without significant difference (P=0.288) and no major adverse effects, such as apnea, occurred in either group.

Conclusions: Rectal midazolam is more effective than ketamine in anxiolysis and mask acceptance. Although they both can ease separation anxiety in children before surgery, we found neither drug to be acceptable for sedation.

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Background: Amino acids have different effects on the growth of some dermatophytes. Some may encourage growth, while others inhibit it. The concentrations of some amino acids also are an important factor for their effect. To investigate the effects of amino acids on the growth of dermatophytes, the dermatophytes Trichophyton schoenleinii and Microsporum canis, obtained from Iran.
Methods: In this study, two concentrations (1g/dL and 0.1g/dL) of 23 amino acids were added to the Sabouraud glucose agar media of these dermatophytes. The experiment was carried out three times. After two weeks, the means of the colonies were compared with the control, which had no amino acids added to the Sabouraud glucose media.
Results: The results showed that L-cysteine hydrochloride, L-cysteine, L-aspartic acid, L-glutamic acid and DL-tryptophan and L-tyrosine had the most inhibitory effects on the studied dermatophytes, while arginine L-lysine and L-methionine had moderate effects and the rest of amino acids had less inhibitory, or even stimulatory, effects on the growth of the dermatophytes. M. canis and T. schoenleinii has a different sensitivity to amino acids. This data indicates that sulfur-containing amino acids and acetic amino acids have greater inhibitory effect against these two dermatophytes. This may be an indicator that such amino acids used in, for example, sweetener may have an important role in immunity to these dermatophytes. Thus, some amino acids may be used as a possible treatment for dermatophytosis.
Conclusion: Among the amino acids L-cysteine hydrocholoride, glutamic acid, aspartic acid, and tryptophan are the most inhibitory effect s against of T. schoenleinii and M. canis.

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Background: The function of internal systems can be influenced significantly by hypernatremia, even anesthesia may be affected by this electrolyte imbalance. The aim of this study was to determine the effects of a single anesthetic dose of ketamine in an experimental rat model of chronic hypernatremia.
Methods: Sixty male Wistar rats, weighing 300(±20)g, were allocated randomly to three groups: the control group received drinking water and test groups 1 and 2 received 1% and 2% NaCl, respectively, for 144 hours. We measured the parameters of sensitivity to the ketamine injection (125mg/kg) including length of times to the inhibition of the righting reflex, inhibition of the response to painful stimulus and the times to the reappearance of the response to painful stimulus and recovery from anesthesia. We also determined the mortality rates during anesthesia.
Results: The times for inhibition of the righting reflex and response to painful stimulus for group 2 were significantly shorter than those for group 1 and the control group. The times for the reappearance of response to painful stimulus and full recovery from anesthesia in group 2 were significantly longer than those of group 1 and the control group.
Conclusions: Hypernatremia affects ketamine anesthesia in the rat, increasing the speed of passing through the different steps of anesthesia. The duration of ketamine efficacy increases, while recovery from anesthesia is significantly delayed.

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Background: Post-tonsillectomy pain is often severe and usually prevents patients from routine eating and drinking. A new option for reducing postoperative pain is "preemptive analgesia", the pre-, intra- or post-operative administration of analgesic agents. Ketamine, an N-methyl D-aspartate receptor antagonist, has recently received attention for this aim. Herein, we study the effect of submucosal injection of ketamine in the tonsillar bed for the reduction of post-tonsillectomy pain.

Methods: In this double-blind clinical trial, three groups of patients underwent infiltration of 0.5mg/kg ketamine, 1mg/kg ketamine or normal saline in their tonsillar bed. Age, sex and weight of patients, duration of surgery, systolic and diastolic blood pressure (before and after surgery), volume of blood loss, reoccurrence of bleeding, time to initiation of oral intake, nausea, vomiting, pain score and dysphasia were recorded in information sheet. Data analysis was performed by one-way ANOVA and chi squared tests, with significance at a P value of <0.5.

Results: There is no significant difference between the three groups with regard to age, sex, weight, duration of surgery, blood pressure (before surgery), volume of blood loss, nausea and vomiting. However, for the ketamine groups, pain score, dysphasia, need for opioid administration and time to initiation of oral intake is significantly lower (P<0.00). Reoccurrence of bleeding was observed in one patient in the lower-dose ketamine group, which is not statistically significant. The effectiveness of the two doses of ketamine is similar, with no statistical difference between the two groups (P=0.84).

Conclusions: This study demonstrated that a submucosal injection of ketamine into the tonsillar bed preoperatively is a safe option for reducing post-tonsillectomy pain, dysphasia, need for opioid and time to initiation of oral intake, without increasing the risk of excessive bleeding, reoccurrence of bleeding, nausea and vomiting.

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Background: It is well known that erectile dysfunction is most commonly associated with diabetes, affecting 35% to 75% of men with diabetes mellitus. Several studies have been carried out to find appropriate strategies for treatment of diabetes-induced erectile dysfunction. The aim of the present study was to investigate the ability of acute administration of the endogenous cannabinoid anandamide in vitro to alter the NANC-mediated relaxation of corpus cavernosum from diabetic rats and the possible role of nitric oxide in this manner.

Methods: Diabetes was induced by the administration of streptozotocin for eight weeks. Corpora cavernosa were isolated in organ baths for measurement of agonist-evoked or electrical field stimulation (EFS)-evoked smooth muscle tensions.

Results: The neurogenic relaxation of phenylephrine (7.5 µM) precontracted isolated corporal strips was impaired in diabetic animals. Anandamide (0.3, 1 and 3 µM) enhanced the relaxant responses to EFS in diabetic strips in a dose-dependent manner. This effect was antagonized by either the selective cannabinoid CB1 receptor antagonist AM251 (1 µM) or the selective vanilloid receptor antagonist capsazepine (3 µM). Concurrent administration of partially effective doses of L-arginine (10 µM) and anandamide (0.3 µM) exerted a synergistic improvement in EFS-induced relaxation of diabetic strips (p<0.001). The relaxant responses to the nitric oxide donor sodium nitroprusside of the subjects in the diabetic and control groups were similar.

Conclusion: For the first time, we demonstrated that acute administration of an endogenous cannabinoid, alone or in combination with L-arginine could improve the NO-mediated relaxation of cavernosal smooth muscle in diabetic rats and this effect was mediated by cannabinoid CB1 and vanilloid VR1 receptors within the tissue.
 

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Background: Obstructive nephropathy has been associated with disorders in metabolism state and oxidative balance of kidney. Stress oxidative play a key role in the pathophysiological processes of renal diseases. The objective of this study was to investigate effects of vitamin-E, as a powerful antioxidant, on renal oxidative stress and metabolism defect induced by 24-hr unilateral ureteral obstruction (UUO).

Methods: Anesthetized male Sprague-Dawley rats (n=10 in each group) were sterilely operated to occlude the left ureter. In UUO+NS, we had a single dose normal saline injection and in UUO+VitE and UUO+OO groups, D-α-tocopherol (50 mg/kg), the main component of vitamin-E, and its vehicle (Olive Oil), respectively, were twicely infused I.P. before and after UUO-induction. There were also sham-operated and control groups. 24-hr after of UUO-induction, both kidneys were removed and stored in -70°C. To determine metabolism condition, the levels of ATP and ADP and to evaluate redox state, the levels of malondialdehyde (MDA) and ferric reducing/antioxidant power (FRAP) of kidneys were assessed.

Results: The comparisons between UUO+NS and sham groups indicated that UUO increased MDA (p<0.001) and ADP (p<0.05), but decreased FRAP, and ATP/ADP ratio in obstructed kidney (all p<0.001). In UUO+VitE group, MDA and FRAP were equal to their levels in sham group, while ATP, ADP and ATP/ADP ratio were not different from those of UUO+NS group in obstructed kidney.

Conclusion: Twenty four hour of UUO caused renal reduction in oxidative metabolism and elevations in reactive oxygen species and administration of vitamin-E, although considerably ameliorated the oxidative stress, could not improve the defected metabolism.

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Background: Epidural fibrosis (EF) is a part of normal physiological tissue response to laminectomy and it may be an important cause of failed back surgery syndrome (FBSS). The objective of this study was to evaluate the effect of using gel foam after laminectomy on reduction of epidural fibrosis.

Methods: In this prospective study forty five rabbits were recruited. The cases undergone bilateral laminectomy at the L4 and L5 lumbar levels under an approved surgical protocol. After eight weeks the rabbits were sacrificed and the spinal segments from L3 to L6 were removed en bloc. The amount of scar tissue at the laminectomy defect was scored. The fibroblast and inflammatory cell counts were also compared between two groups.

Results: In this study 55% of group A rabbits were placed in grade 0 or I, grade II fibrosis could be detected in the remaining 45%. In group B these amounts were 73.7% and 26.3% respectively, which no significant statistical difference could be detected between two arms (p=0.189). Comparing the quantity of fibroblasts 40% of group A rabbits were recognized as grade I and the other 60% as grade II and grade I fibrosis was discovered in 42.1% of group B rabbits, while other 57.9% suffered from grade II fibrosis, again no significant statistical difference could be attributed between two arms (p=0.576). Also comparing inflammatory cell counts detected in the specimens no significant statistical difference could be detected either (p=0.465).

Conclusion: According to this study using gel foam during the laminectomy surgery in rabbits has no obvious effect in reducing post laminectomy epidural fibrosis after eight weeks of follow-up.

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Background: Axillary block is used for inducing anesthesia in outpatient hand and forearm surgeries. Few researches have studied hemodynamic and blockade effects of low doses of Epinephrine. The aim of the present study was to compare the duration of analgesia and hemodynamic changes following the injection of high/low epinephrine doses in such surgeries.

Methods: The present randomized clinical trial study was conducted on healthy individuals (ASA I-II) who were candidates for hand and forearm surgeries. The patients were randomly divided into three groups. The first two groups were allocated to receive lidocaine with low (0.6µg/cc) and high (5µg/cc) doses of epinephrine whereas lidocaine plus normal saline was injected in the third group. The hemodynamic changes (Mean arterial blood pressure and heart rate) and the occurance of any side-effects along with the duration of analgesia and motor block were recorded.

Results: From among the total of 75 patients, 15 cases were excluded due to incomplete blockade or failure needing general anesthesia. The duration of analgesia and the motor block were longer in the high dose epinephrine group, the difference, however, was not statistically significant. Heart rate changes within the groups was significant in the 4^th-7^th and 10^th minutes. Mean arterial blood pressure changes was only significant in the 4^th minute, within the groups.

Conclusions: Administering low doses of epinephrine plus lidocaine as a local anesthetic not only provides acceptable analgesia compared to higher doses of the medication, but also is associated with fewer side effects.