Prevalence and risk factors of ecstasy use among college students in Astara, Islamic Republic of Iran.

We determined the prevalence and risk factors for 3,4-methylenedioxy-methamphetamine (MDMA, "ecstasy") use among college students in Astara, a northern border city of Iran. In a cross-sectional questionnaire survey of 1226 students, the lifetime prevalence of ecstasy use was 5.6%. The lifetime prevalence of use of other drugs, mostly cannabis and opium, was 4.6%. A fifth of students (21.8%) were current cigarette smokers and 24.8% had ever used alcohol. After logistic regression, the factors influencing ever use of ecstasy were ever use of other drugs, ever use of alcohol, current cigarette smoking and living alone or with friends. Targeted prevention programmes should be conducted in all colleges.

Effects of Plantar Flexor Muscles Fatigue on Postural Control during Quiet Stance and External Perturbation in Healthy Subjects.

BACKGROUND: The maintenance of postural control is a key component in dynamic physical activity, especially during muscle fatigue and against external forces. Despite many studies in this field, there is no consensus regarding the effects of plantar flexor muscles fatigue on postural control during different postural tasks. OBJECTIVE: To evaluate the effects of plantar flexor muscles fatigue on postural control during quiet stance and external perturbation in healthy subjects. MATERIAL AND METHODS: Twenty four healthy individuals (20-35 years) participated this interventional study. The foot center of pressure data was measured using a single force platform, and then the postural control parameters, including the center of pressure displacement and velocity in the anterior-posterior and medial-lateral direction and also path length calculated under two conditions; quiet and perturbed stance, before and after plantar flexor muscles fatigue. RESULTS: The statistical analysis demonstrated that mean displacement and velocity of the center of pressure in the anterior-posterior direction and also path length increased after the fatigue protocol in the perturbed condition. However, fatigue had no significant effects on postural control parameters in the quiet standing condition. CONCLUSION: These results indicated that the effects of muscle fatigue on postural control depend on the difficulty of the task and the relevance of proprioceptive information. The postural control system appears to use distinct control strategies in different situations such as quiet and perturbed stance conditions, and these strategies may be differentially altered by fatigue. In conclusion, due to the potential risk of loss of balance, it is important to take the role of plantar flexor muscle fatigue into account during more difficult postural tasks.

CD26 expression on CD4+T cells in patients with cutaneous leishmaniasis.

Surrogate marker(s) of protection in human leishmaniasis is not well defined. In this study, T helper 1 (Th1) and Th2 cytokine profiles and CD26 expression on CD4(+) T cells in peripheral blood mononuclear cells of patients with healing or non-healing forms of cutaneous leishmaniasis (CL) stimulated with Leishmania antigens were assessed. The level of interferon (IFN)-gamma production was significantly higher in patients with healing or non-healing forms of CL than in healthy controls, but it was not significantly different between the two patient groups. The level of interleukin-5 production was significantly higher in patients with the non-healing form of CL than in the two other groups. There was a significant increase in the level of CD26 expression on CD4(+) T cells in patients with healing (P < 0.001) or non-healing (P = 0.025) forms of CL compared with the control group, but no significant difference was seen between the two patient groups. A weak positive correlation was seen between IFN-gamma production and CD26 expression on CD4(+) T cells of patients with the healing form of lesion (r = 0.54, P = 0.008), but this correlation was not observed in patients with the non-healing form of CL (r = 0.53, P = 0.078). Surface CD26 is not correlated with the clinical manifestation of CL or IFN-gamma production. Therefore, CD26 is not a surrogate marker for IFN-gamma production in CL.

Prevalence of hepatitis C virus infection and risk factors of drug using prisoners in Guilan province.

This was a cross-sectional prevalence study to determine the prevalence of hepatitis C virus (HCV) and high-risk behaviours in drug abusers admitted to prison in Guilan province, northern Islamic Republic of Iran. Subjects were asked about risk behaviours for acquiring HCV and blood was drawn for HCV antibody testing using ELISA techniques. Of 460 inmates, the mean duration of drug use was 8.9 years; 51.7% were opium users and 18.3% heroin users. HCV risk behaviours were common in this population and 209 inmates (45.4%) were HCV antibody positive (88.9% of intravenous drug abusers). HCV-positive status was significantly associated with intravenous drug use, having skin tattoos and number of times in prison.

Seroprevalence of hepatitis C and risk factors in haemodialysis patients in Guilan, Islamic Republic of Iran.

We assessed the prevalence of hepatitis C virus (HCV) infection and associated risk factors for all 298 haemodialysis patients in 7 dialysis units in Guilan province. Serum samples were screened for anti-HCV antibodies using a second generation enzyme-linked immunosorbent assay. Positive samples were confirmed by immunoblot assay. Overall prevalence was 24.8% (range: 9%-40%; 95% CI: 19.9-29.7): 80 patie.nts tested positive and 74 were confirmed positive by immunoblot assay. Length of time on dialysis and history of rejected kidney transplant were statistically significantly associated with HCV infection. Age, sex and previous blood transfusion were not associated. Nosocomial transmission may play a role in the spread of HCV in haemodialysis units. A separate dialysis system should be used for seropositive HCV patients.

Impact of road traffic accidents on the elderly.

INTRODUCTION: Older adults are a vulnerable road user group with high mortality and morbidity in road crash. The aim of this study was to show pattern of road traffic injuries in this special aging group. METHODS AND MATERIALS: In a cross sectional study, pre-hospital emergency system reports, hospital and police records of all motor vehicle collisions injured above 60 years old who were admitted to Pour-Sina hospital from April 2011 to March 2012 were studied. Demographic data, characteristic of road traffic incidents and in-hospital medical profiles were derived. Data were analyzed with SPSS ver. 18. Differences between demographic and injuries situation were calculated by chi square test. A p-value of <0.05 was considered statistically significant. RESULTS: One thousand three-hundred six old injured were admitted during study period that this amount accounted for 8.7% of total road accident injured. Mean age of them was 70.9 ± 6.7 years. Most of them were male (74.7%). 40.5% were pedestrians, 22.1% were car occupants and 19.1% were motorcyclists.76.7% had multiple trauma. Head and neck were the most prevalent regions of injured. Total in-hospital mortality rate was 10.1% that was higher in old elderly pedestrians and motorcyclists in comparison to young elderly (16.1% vs. 7.9%) and other type of victims (ρ<0.000). RESULTS: One thousand three-hundred six old injured were admitted during study period that this amount accounted for 8.7% of total road accident injured. Mean age of them was 70.9 ± 6.7 years. Most of them were male (74.7%). 40.5% were pedestrians, 22.1% were car occupants and 19.1% were motorcyclists.76.7% had multiple trauma. Head and neck were the most prevalent regions of injured. Total in-hospital mortality rate was 10.1% that was higher in old elderly pedestrians and motorcyclists in comparison to young elderly (16.1% vs. 7.9%) and other type of victims (ρ<0.000). CONCLUSION: High mortality rate of road traffic injuries in this group especially in pedestrians should be taken into consideration and strategies aimed at the road-user safety including periodic medical examination and improvement of road structure and facilities.

Identification and distribution of peripheral benzodiazepine binding sites in male rat genital tract.

In the present study we identified and characterized the distribution of high-affinity peripheral benzodiazepine binding sites (PBzS) in male rat vas deferens (whole, and prostatic and epididymal portions), prostate, seminal vesicles, and Cowper's glands. [3H]PK 11195, an isoquinoline carboxamide derivative, was used as a radioligand specific for PBzS. Scatchard analysis of saturation curves of [3H]PK 11195 binding in the whole vas deferens, the prostatic and epididymal portions of the vas deferens, the prostate, the seminal vesicles, and Cowper's glands yielded mean maximal numbers of binding sites of 1211 +/- 158, 1012 +/- 311, 1451 +/- 156, 1805 +/- 86, 865 +/- 51, and 2251 +/- 135 fmol/mg protein, respectively. The equilibrium dissociation constant values ranged between 1 and 3 mM in all the above tissues. The ability of various drugs to displace the specific binding of [3H]PK 11195 from PBzS in Cowper's gland membranes was also tested. The inhibition constants for Ro 5-4864, diazepam, and PK 11195 were 28, 330, and 4 nM, respectively, whereas clonazepam, Ro 15-1788, and testosterone were inefficient in displacing [3H]PK 11195. The presence of high densities of PBzS in the male genital tract suggests a functional role in these hormone-dependent organs.

Adrenal mitochondrial benzodiazepine receptors are sensitive to agents active at the dopamine receptor.

Male rats were treated for 21 days with drugs known to affect prolactin secretion, in order to assess the effects of these drugs on mitochondrial benzodiazepine receptors (MBRs). Sulpiride, a selective dopamine D2 receptor antagonist and hyperprolactinemic agent, decreased MBR density in the adrenal gland (49%; P < 0.005), whereas metoclopramide, another dopamine antagonist with a preference for dopamine D2 receptors, increased adrenal gland MBR density (31%; P < 0.05). Bromocriptine, a specific dopamine agonist, increased MBR density in this organ (87%; P < 0.001). None of the three agents influenced kidney or testicular MBRs. These data indicate that the mechanism of organ-specific alterations in MBRs seems to be prolactin independent.

Effects of chronic prenatal, neonatal and adult exposure to barbiturates on mitochondrial benzodiazepine receptors in mouse testis.

In the present study we investigated the effect of chronic exposure to phenobarbital, administered to mice during the prenatal or neonatal period, as well as to adult mice, on mitochondrial benzodiazepine receptors in the testis. Three modes of treatment were investigated: (1) offspring of pregnant mice receiving food containing 3 g/kg phenobarbital until gestational day 18 were killed at 22 or 50 days of age and assayed for receptor binding (prenatal group); (2) offspring of untreated mice were injected subcutaneously once daily with 50 mg/kg phenobarbital on days 2-21 of age and killed at 22 or 50 days of age (neonatal group); (3) adult mice were injected subcutaneously once daily for 3 weeks with 50 or 100 mg/kg phenobarbital (adult group). Prenatal or neonatal exposure to phenobarbital did not alter the testicular weight in all groups (except for the neonatally exposed group killed at 22 days of age), or the mitochondrial benzodiazepine receptor binding characteristics. However, the maximal number of these receptors in the testes of mice in the adult group receiving 100 mg/kg phenobarbital was significantly increased (42%, P < 0.05), compared to controls. The administration of 50 mg/kg phenobarbital to the adult group also induced an increase (27%, non-significant) in testicular mitochondrial benzodiazepine receptors. Phenobarbital administration did not affect the receptor affinity values or the weight of the testis. It is unclear whether these receptor alterations due to chronic phenobarbital exposure of adult mice reflect functional changes in the testis.

Testosterone prevents castration-induced reduction in peripheral benzodiazepine receptors in Cowper's gland and adrenal.

The effect of surgical castration of adult male Sprague-Dawley rats on peripheral and central benzodiazepine (BZ) receptors was studied. Following removal of the testes, a significant decrease in the density of peripheral BZ receptors (PBR) was observed in Cowper's glands (71%; P less than 0.005) and the adrenal (31%; P less than 0.01), but not in the heart. Administration of testosterone acetate (TA) prevented castration-induced PBR depletion. Orchiectomy per se, as well as TA administration to castrated rats, had no effect on central or peripheral BZ receptors in whole brain without the cerebellum. These results indicate the regulatory role of testosterone in the regulation of PBR in Cowper's glands and adrenal.

Testosterone and cyproterone acetate modulate peripheral but not central benzodiazepine receptors in rats.

Sixteen days of testosterone acetate (TA) treatment in male rats induced an increase in the densities of peripheral benzodiazepine receptors (PBR) in the adrenal and Cowper's glands and a decrease in PBR density in the testis. TA did not alter PBR density in the heart, cerebral cortex, or pituitary, or central benzodiazepine receptor (CBR) density in the cerebral cortex or hypothalamus. The antiandrogenic agent cyproterone acetate induced a decrease in PBR density in the testis, adrenal, and pituitary, but did not affect PBR density in Cowper's glands, heart, or cerebral cortex, or CBR density in the cerebral cortex or hypothalamus. In all of the above organs, affinity values did not change following the treatment with both agents. The receptoral changes may be relevant to the physiological and neurobehavioral effects of the chronic exogenous androgenic and antiandrogenic treatment.

Mouse strains differ in their sensitivity to alprazolam effect in the staircase test.

The behavioral responses of five mouse strains (inbred: C57 and BALB/c; outbred: Swiss, ICR and HS/Ibg) to alprazolam was examined in the staircase test, an animal model sensitive to benzodiazepines (BZs). Alprazolam administration resulted in a dose-dependent suppression of rearing behavior, but to a different extent among the strains. By contrast, the number of stairs ascended was not suppressed by alprazolam at doses of 0.25 and 0.5 mg/kg, except in the C57 mice. The addition of flumazenil antagonized the alprazolam effect on rearing and climbing in all strains. There was a consistency within strains in sensitivity to alprazolam, with some strains being highly sensitive (C57 and HS) or less sensitive (Swiss, ICR and BALB/c) with regard to both rearing and climbing behaviors. Serum alprazolam levels did not differ significantly among the strains. This strain-dependent pattern of response to alprazolam seems to indicate a genetic component, rather than pharmacokinetic, in the behavior sensitivity to the BZ, with a spectrum of degree of responsivity among strains.

The cyclic AMP second messenger system in man: the effects of heredity, hormones, drugs, aluminum, age and disease on signal amplification.

The intracellular effects of a number of hormonal signals are mediated by the cyclic AMP second messenger system in man and the ubiquitous distribution of hormone-stimulated adenylate cyclase suggests the importance of this enzyme complex in normal aging and pathophysiological states. Various vectors including heredity, endogenous catecholamines, steroid hormones, and drugs affect the activity of hormone-stimulated adenylate cyclase in man. The effect of heredity was studied using lymphocytes obtained from monozygotic twin pairs and age and sex-matched sib pairs. Only for forskolin-stimulated activity is a significant proportion of individual variance attributable to heredity, suggesting the relative stability of the catalytic subunit. Beta-adrenergic and prostaglandin E-1 activity are "state" characteristics and their activities are controlled by environmental parameters. A significant reduction in isoproterenol-stimulated cyclic AMP accumulation between the menses and luteal phase of the menstrual cycle is observed in lymphocytes obtained from 11 female subjects. The lowest level of beta-adrenergic receptor activity is associated with the highest levels of progesterone and estradiol hormone levels in blood. Lithium at therapeutic concentrations markedly inhibits adenylate cyclase activity in platelet membranes. Moreover, marked individual differences are observed in sensitivity to lithium as determined by Dixon plot derived Ki values for 9 normal, healthy subjects. Human adenylate cyclase obtained from platelets and lymphocytes is activated by micromolar amounts of aluminum in the presence of NaF. Irreversible activation of adenylate cyclase by aluminum is suggested as a possible mechanism of this metal's neurotoxicity. The biochemical basis for the age-associated decline in beta-adrenergic responsiveness in man is discussed. Several investigations suggest a deficit at two levels in the adenylate cyclase complex: an impaired coupling of the receptor/N protein subunits and an additional lesion distal to the receptor at the level of N/C coupling. Perfusion studies with salbutamol suggest that the decline in beta-adrenergic sensitivity is general and not restricted to lymphocytes. Possible abnormalities in cyclic AMP signal amplification and recognition in various disease states is discussed. Increased prostaglandin E-1-stimulated cyclic AMP accumulation is observed in lymphocytes obtained from patients with Alzheimer's disease compared to age-matched controls and correlated with severity of the disease state.(ABSTRACT TRUNCATED AT 400 WORDS)

Modulation of peripheral benzodiazepine receptors in female rat genital organs by various gonadal steroids.

Peripheral benzodiazepine receptors (PBR) in the ovary, oviduct, uterus, and kidney of immature rats were studied under short- and long-term treatment with testosterone (T), progesterone (P4), and diethylstilbestrol (DES). A significant increase in PBR specific binding was observed after 4 days' treatment with T in the ovary (1.6-fold), oviduct (2.0-fold), and uterus (1.4-fold) compared with intact rats. Four days' treatment with P4 increased PBR specific binding in the ovary (1.5-fold), but no changes were detected in the oviduct or uterus. In contrast, PBR specific binding was significantly reduced by 10 days' treatment with T or P4: 40 and 12%, respectively, in the ovary and 35 and 40%, respectively, in the oviduct. Ten days' treatment with T reduced PBR specific binding in the uterus by 25%, but the same interval of treatment with P4 did not alter specific binding in the uterus. Four or 10 days' treatment with DES significantly increased PBR specific binding in the ovary (1.5-fold), oviduct (2.4-fold), and uterus (1.9-fold). Scatchard analysis revealed that the changes in the PBR specific binding were due to a change in PBR density values rather than PBR affinity values. No change in PBR specific binding was found in the kidney following any of these treatments. Taken together, it is suggested that PBR density in the ovary is altered by exogenously administered steroids that usually are biosynthesized in the ovary. Additionally, the altered PBR density in the oviduct and uterus via the various steroids employed may imply that changes occurring in ovarian steroidogenesis should affect PBR density in these organs.

Effect of lithium in vitro and after chronic treatment on human platelet adenylate cyclase activity: postreceptor modification of second messenger signal amplification.

LiCl in vitro markedly inhibits forskolin-stimulated human platelet adenylate cyclase activity by competing competitively with Mg2+ for a site on the catalytic subunit. The sensitivity of platelet membrane adenylate cyclase to lithium inhibition for individual manic patients was determined by the Dixon plot procedure: marked individual differences in sensitivity to lithium were observed pretreatment (0.66 mM-3.15 mM LiCl). After 3 weeks of continuous treatment with lithium in vivo a significant decrease in adenylate cyclase affinity for lithium was observed (pretreatment average Ki = 1.38 +/- 0.92 mM vs. treatment average Ki = 2.98 +/- 1.35 mM LiCl, n = 10). The clinical implications of these findings relating to chronic lithium exposure are discussed.

Up-regulatory effect of triphasic oral contraceptive on platelet 3H-imipramine binding sites.

Triphasic oral contraceptive (Logynon) induced a significant increase (36%) in the maximal binding capacity of platelet membranes for [3H]imipramine. The increase was achieved in the second Logynon cycle as compared to pretreatment and first Logynon cycle binding values. The pill contains a combination of ethinyl estradiol and levonorgestrel, and it is as yet unclear which of the two hormones is responsible for the up-regulatory effect. The increase in the density of platelet imipramine binding sites may reflect a similar alteration in brain. The increase in imipramine binding did not correlate with alteration in mood as assessed by Beck Depression Inventory scores.

PIP: As an indicator of analogous brain serotonin metabolism, and by extension of depression tendency, platelet imipramine receptors were measured in women taking the triphasic oral contraceptive Logynon. Logynon (Schering AG Berlin/Bergkamen, Germany) contains levonorgestrel 50 mcg for 6 days, 75 mcg for 5 days and 125 mcg for 10 days, followed by 7 days pill-free; ethinyl estradiol doses are 30, 40 and 30 mcg for the same periods of time. The mean imipramine binding values (Bmax), calculated from Scatchard plots of tritiated uptake by platelets, was 429 in the control cycle, 396 on Day 14 of the 1st treatment cycle, and 582 in the 2nd treatment cycle (p0.02 vs pretreatment). Control means were 412 and 411. No significant differences were seen in affinity (Kd). There were no significant differences in mean Beck Depression Inventory tests, although 1 woman became clinically depressed, with BDI scores of 22 and 33 compared to 2 before taking Logynon. Her Bmax values were 626, 630 and 796 in the pretreatment, 1st and 2nd cycles respectively. Overall, the increase in imipramine binding did not correlate with Beck depression inventory scores.

Vitamin D status in relation to postural stability in the elderly.

OBJECTIVES: Postural instability (PI) is an important risk factor for falls, especially in the frail older population. In this study, we investigated the impact of vitamin D deficiency on PI in a sample of community dwelling older subjects. Our objective was to determine the potential association between vitamin D deficiency and PI in older fallers. DESIGN: Cross-sectional study. SETTING: Falls and Fractures Clinic, Department of Geriatric Medicine, Nepean Hospital, Penrith, Australia. PARTICIPANTS: One hundred and forty-five adults aged 65 years and older who have had at least one episode of a fall within the six months prior to assessment at the Falls and Fractures Clinic. MEASUREMENTS: Serum 25(OH) vitamin D3 [25(OH)D3] and parathyroid hormone concentrations were determined at baseline. Subjects were separated into 3 groups based on serum 25(OH)D3 levels with the following cut-off values: < 30 nmol/L (deficient), 30-50 nmol/L (insufficient) and > 50 nmol/L (normal). Other baseline measurements included body mass index, mini-nutritional assessment, grip strength, serum calcium concentration and creatinine clearance, which were used as covariables. PI was assessed using a computerized virtual reality system (Medicaa, Uruguay). Measured parameters included limits of stability (LOS) and centre of pressure (COP) under eyes closed on foam (ECF) and visio-vestibular stimulation. The estimated swaying area, computed from the ellipse of confidence under eyes closed standing on foam (ECF), was also used as a PI parameter. Gait velocity (GV) was measured using a GaitRITE walkway system. RESULTS: Posture was impaired in vitamin D deficiency (<30 nmol/L) as indicated by lower LOS (90 +/- 18), higher ECF (25 +/- 10) and slower GV (55 +/- 7) as compared with the insufficient and normal groups. After adjustment for demographic, biochemical and anthropometric variables, vitamin D deficiency significantly correlated with low LOS and high COP under ECF. CONCLUSION: Low levels of vitamin D were associated with PI. This association could also have an effect on slow GV and increased risk of falls. In conclusion, using an objective method to measure balance in older fallers we have identified a novel role of vitamin D in balance control. Prospective studies are required to confirm the effect of vitamin D on PI and elucidate the mechanisms of this association.

Prevalence and factors associated with Ecstasy use among college undergraduates in north of Iran-2005.

We conducted a cross sectional study of 3958 college students in north of Iran in 2005 with an anonymous questionnaire that was adapted from the questionnaires used in "Monitoring the future". Three thousand seven hundred students responded (93.5%). Lifetime prevalence use of ecstasy, opium and cannabis was 4.3%, 2.7% and 2.4% respectively. The prevalence of current cigarette smoking was 19.5%. After the logistic regression, the factors influencing ecstasy use were use of other illicit drugs, alcohol and cigarette smoking (P<0.000), widow or divorced (ρ=0.007) and higher educational background of mother (ρ=0.019).