Effects of saffron [Crocus sativus L.] stigma extract and its active constituent crocin on neuropathic pain responses in a rat model of chronic constriction injury

This study was designed to investigate the therapeutic effects of saffron [Crocus Sativus L] and its main constituent crocin on neuropathic pain behavioral responses induced by chronic constriction injury [CCI] in rats. Adult male Wistar rats [200 to 250 g] were randomly assigned into 5 groups: Sham + saline, CCI + saline, CCI+ saffron [30 mg/kg], CCI +crocin [15 mg/kg] and CCI + crocin [30 mg/kg]. CCI was induced by applying 4 loose ligatures around the sciatic nerve. Two weeks after nerve lesion, injections of saline, saffron or crocin were started and continued until 26th day post-surgery. Pain behavioral responses including mechanical allodynia [von Frey filament testing] and thermal hyperalgesia were measured in 14, 17, 20, 23, 26, and 40th days after CCI. CCI significantly increased pain behavioral responses. Saffron and crocin [30 mg/kg] decreased thermal hyperalgesia and mechanical allodynia on day 26, and this effect continued until the day 40. Crocin at lower dose [15 mg/kg] was ineffective. These findings indicate that treatment of saffron and crocin after CCI may have a therapeutic effect against neuropathic pain, suggesting that these substances may offer new strategies for the treatment of this highly debilitating condition

Glucocorticoids interact with cholinergic system in impairing memory reconsolidation of an inhibitory avoidance task in mice

Introduction: Recent studies suggest that glucocorticoids modulate memory reconsolidation. Moreover, cholinergic system is involved in memory reconsolidation. Since glucocorticoids interact with brain cholinergic system in modulating memory processing, we investigated whether glucocorticoid influences on the reconsolidation of emotionally arousing training depend on the cholinergic system

Methods: Mice were trained [1mA, 3s footshock] in an inhibitory avoidance task. Forty-eight hours after training, memory reactivation was occurred [Test 1], and different treatments were given. Two [Test 2], five [Test 3], and seven days [Test 4] after memory reactivation [Test 1], animals were retested for fear memory retention

Results: In the first experiment, we observed that administration of corticosterone [CORT, 0.3, 1 and 3 mg/kg] following memory reactivation impaired subsequent expression of memory in a dose-dependent manner. In the second experiment, we found that CORT-induced impairment of memory reconsolidation was reversed by the muscarinic receptor antagonist atropine [0.5 and 2 mg/kg]. In the third experiment, the nicotinic receptor antagonist mecaylamine [0.5 or 2 mg/kg] was not able to block the corticosterone response

Discussion: These findings indicate that glucocorticoids impair memory reconsolidation by a muscarinic cholinergic mechanism

Correlation of fear memory in a PTSD animal model and hippocampal BDNF in response to beta-estradiol treatment

The most important characteristics of PTSD, as an anxiety disorder, are memory disorders and hippocampus is one of the essential structures which plays a critical role in PTSD memory disorders. Traumatic events cause apoptosis and alter the expression of neurotrophic factors in hippocampus. The aim of this study is to evaluate the effects of beta-Estradiol on behavioral responses in PTSD and to study its biochemical and histological mechanisms

We used single prolonged stress [SPS] to develop PTSD in rats. The day after, the rats received electrical foot shock within shock chamber. One week later, in order to test the conditioned fear responses, the freezing behavior of rats were examined for 5 continuous days, as they were placed back in the chamber without any shock. Animals received multiple injections of beta-estradiol or sesame oil, immediately after shock and also on a daily basis through the seven days prior to the test. Hippocampal cell count was implemented after cresyl violet staining. We measured BDNF protein levels by ELISA kit

Main findings of this study confirmed that exaggerated fear response is observed in PTSD group as compared with control group and beta-estradiol administration reduced these exaggerated behavioral responses. We found out that SPS decreases the density of cells in hippocampus and this effect is partly corrected by beta-estradiol; beta-estradiol increased BDNF protein level in hippocampus as compared with PTSD group; BDNF protein level was negatively correlated with freezing response in both SPS+beta-estradiol and SPS+sesame group

The results of this study is consistent with the hypothesis that decreased expression of BDNF contributes to memory impairment in PTSD and up regulation of BDNF by beta-estradiol plays a role in memory treatment

Hypocalcemic seizure and related factors after neonatal period; A single-center, retrospective study

Seizures are the most common disorder of the central nervous system in childhood and constitute a significant number of admissions to the pediatric emergency departments. The aim of this study is evaluate the etiology of hypocalcemic seizures in pediatrics. A single-center, hospital based descriptive study was done in the academic referral center for hypocalcemic seizure of Tehran University of Medical Sciences, Iran. Data was evaluated based on the medical records of each patient. Case files of these children's were analyzed for age at presentation, sex, weight, clinical features, biochemical parameters [serum calcium, magnesium, phosphorus and alkaline phosphatase] ,type of seizure, history of previous seizure and history of drug intake. A total 38 children with hypocalcemic seizure, consisting of 19 boys and 19 girls, with ages ranging from one month to 14 years, were enrolled in this study. The most common patterns of seizures were generalized seizures [83.8%]. the mean levels of serum alkaline phosphatase was significantly greater in patients under the age of 2 years [1234 +/- 541.03] rather above than 7 years of age [922.75 +/- 147.45] [p = .021]. Rickets was the commonest cause of seizures rickets were diagnosis in 80.8% subjects under 2 years of age, whereas none of those over 7 years old had not rickets , these results were statistically significant [p = .015]. Current observational study indicates that rickets could be a major cause of hypocalcemic convulsion in infants and children. Screening children presenting with hypocalcemic convulsions for rickets and/or other cause of hypocalcemia can help in early diagnosis and institution of specific therapy

[Serum lipids status and its disorders among 30-70 years old population in Semnan province, Iran]

Cardiovascular diseases are the most common cause of mortality and morbidity in new societies. Dyslipidemia is one of the main causes of coronary artery disease. Since there is not comprehensive information about this subject, we aimed to survey dyslipidemia in urban and rural communities/areas in Semnan province. An epidemiologic cross-sectional study was conducted among 3799 persons who were 30-70 years old in Semnan Province, Iran. Multistage cluster sampling was performed, and subjects were selected from urban and rural populations of Semnan, Shahroud, Garmsar and Damqan. Data were collected through questionnaires, then a blood sample was collected from selected patients with 12 hours fasting for evaluation of triglyceride [TG], cholesterol, high density lipoproteins [HDL] and low density lipoproteins [LDL] levels in urban and rural communities. Totally, 3799 persons enrolled in this study with mean age 41 +/- 10.2 years that 44.6% of them were male. High TG was seen in 29.1%, high LDL in 11.8% and low HDL in 30.7%. Prevalence of all kinds of dyslipidemia was higher in Shahroud. In conclusion, prevalence of dyslipidemia among 30-70 years old was higher than expected. So that, comprehensive preventive and educational programmes on lipid disorders and related diseases are necessary

[Effects of acute stress and corticosterone on fear memory extinction in mice]

Memory extinction is the process that being after recalled and actively previously consolidated memories. Although recent studies suggest that acute stress and glucocorticoids have modulatory effects on fear memory extinction, but their effects are not known clearly. The aim of this study was to determine the effects of acute stress and corticosterone on fear memory extinction in passive avoidance task in mice. In this experimental study, 48 male albino mice [25-30 gr] were used, which were trained in one trial inhibitory avoidance task [1mA, 3 s footshock]. Corticosterone [0.5, 1 and 3 mg/kg] was systemically administrated 30 min prior to memory reactivation. In addition, acute stress was induced in some groups using restrainer [plexiglass tube] for 10 min at the same time of cortisterone adminstration. The process of memory extinction was assessed by retention tests given 2, 5, 7 and 9 days after memory reactivation. The latency to re-enter dark compartment of the apparatus was recorded. The results showed that systemic injection of corticosterone [1 or 3 mg/kg] or acute stress facilitates fear-related memory extiction significantly. Our findings indicate that glucocorticoid system and acute stress play an important role in fear memory extiction. Our findings might be helpful to develop therapeutic methods to treat pathological emotional memories such as those seen in post-traumatic disorders and phobia

[Epidemiology of smoking in an Iranian population [Semnan province]: a population-based study]

Cigarette smoking is a known cause of systemic disorders such as bronchogenic carcinoma and cardiovascular diseases. The aim of this cross-sectional study was to estimate prevalence of smoking in 30-70 year old men in Semnan province in Iran. This survey was conducted in a sample population of 1695 men 30-70 years old, in October 2005 to February 2006 in both rural and urban areas of Semnan province. A multistage clustered sampling was performed with, first, 760 clusters [households] selected randomly using a systematic sampling technique. Then one or two more households in the neighborhood of each of the former households were also selected. Finally, in each household a 30-70 year old person was randomly selected and asked to complete a questionnaire. The overall prevalence of current cigarette smoking in men 30-70 years old was 24.1% [95% confidence interval: 22.1-26.1%].18.3% of them were daily and 5.8% occasional smokers. 26.8% of rural and 23.0% city resistant adults were cigarette smokers [P=0.053]. Prevalence of cigarette smoking in under 40, 40-49, 50-59 and >/= 60 years were 21.1%, 32.6%, 25.1% and 11.9%, respectively [all, P<0.001]. 19.7% of illiterates, 24.9% of primary, 30.8% of intermediate, 25.4% of high school and 11.8% of university level education were cigarette smokers[P<0.001]. 46.6% of them before, and 39.2% between 21-30 years have started cigarette smoking. Mean [ +/- SD] age for starting cigarette smoking was 24.1 +/- 8.0 years. Prevalence of cigarette smoking in Semnan, Damghan, Garmsar and Shahrood were 22.5, 23.2, 27.6 and 23.4% [P=0.554], respectively. Only 0.1% and 1.6% of them were pipe and tobacco smokers, respectively. 0.4% tobacco smoking was simultaneously with cigarette smoking. 15.2% non-cigarette smokers were passive smokers. Overall, 39.3% of Semnan province adults, aged 30-70 years, were active or passive cigarette smokers. Findings showed that prevalence of cigarette smoking in Semnan province in adults aged 30-70 years is high. Therefore, a community-based multiple strategies are required to combat with increasing rate of cigarette smoking and its complications

Prenatal exposure to maternal voluntary exercise during pregnancy provides protection against mild chronic postnatal hypoxia in rat offspring

Postnatal hypoxia is a main cause of neuronal damage in newborn. However, our understanding of the possible preventive or therapeutic methods to reduce the harmful effects of hypoxia is still primary. Pregnant rats were provided with running wheels during their pregnancy. On PND4 [postnatal day 4] to PND8, the rat pups were exposed to postnatal chronic hypoxia [11% O[2], 89% N[2]] in an air-tight plastic chamber for a period of six hours per day. The number of neurons and also angiogenesis in hippocampus were studied. Postnatal exposure to mild hypoxia decreased the number of the neurons in all studied regions of the hippocampus CA1, CA3 [cornu ammonis], DG [dentate gyrus] and SUB [cubiculum] in rat pups. In other words the number of the neurons in rat pups born from voluntary exercise group was not significantly less than control group in CA1, CA3 and DG regions. So maternal Voluntary exercise during pregnancy increases the blood vessel density in the DG region of the hippocampus of the rat pups. In this study for the first time we provide evidences that show the protective effect of maternal voluntary exercise during pregnancy on rat offspring against postnatal hypoxia. We revealed that maternal exercise during pregnancy increases the hippocampal neuron number and angiogenesis in offspring

[ investigation of factors influencing student evaluation of teacher performance: a comprehensive study in Semnan University of Medical Sciences]

Student evaluations provide teachers with important feedback from the consumer's pointof-view. Although substantial research has been conducted with regard to the factors influencing reliability and accuracy of student evaluation of teaching quality, but the results are controversial and need to further research. Thus, this comprehensive study was conducted to determine the role of different factors influencing student evaluations of teacher faculty at Semnan University of Medical Sciences students, Iran. This analytical-descriptive study was conducted with participation of all students at least at the levels of the second semester to up of their education program at Semnan University of Medical Sciences in the academic year of 2009. A questionnaire containing demographic data and some factor influencing on teacher evaluation including effective teaching skills [9 questions], faculty personal characteristics [15 questions], educational principles and laws [1 question], personal characteristics and attitudes of students toward lessons [10 questions], daily time and place of lecture presentation [4 items], and teacher evaluation process at the University [6 questions] was given to each student before the starting of lecture at the classroom. The questionnaires were collected, and the data were analyzed using appropriate statistical methods appropriate. Results showed that from the viewpoints of students proficiency on the course [94%], goodtempered [93 percent], confidence [92.7%], expressive power [91 percent], organizing the contents and having interest to teaching [90%], personality [90 percent], and old or up-to date of teaching materials [83%] have high and higher influences on student evaluation of teacher quality. Most Students [63.3%] expressed that their personal issues have low up to very low influence on teacher evaluation. Additionally, a significant relation between the gender [P<0.001], native and non native status [P<0. 01] and study field of students [P<0. 01] with teacher evaluation score was found. Finally, no significant relation was observed between student rating with faculty evaluation [P>0. 05]. The results of this study showed that acdamemic capability [such as academic proficiency and providing new and updated scientific information on the course subject] is one of the most important factor influencing teacher evaluation outcomes. Also, it seems that not only teaching methods, but also teacher personality can increase student enthusiasm and motivation for learning that ultimately improve the quality of education

[Effect of passive and active recovery from supramaximal exercise on blood lactate levels in male athletes]

One important factor of fatigue occurrence among athletes, following heavy sport activities, especially sports activities with short time and the maximum speed and intensity, is the accumulation of lactic acid in blood. The need for athletes to achieve natural conditions and to prepare for the next activities, methods of disposal lactic acid are very important. The purpose of this study was to study the effects of passive and active recovery with the severity of 55, 60 and 65 percent of maximum heart rate, on levels of blood lactic acid. This semi-experimental study was carried by 60 male athletes' students who were divided randomly to four groups. The first group included 15 subjects of group programs for passive recovery and the second, third and fourth groups of the state quarter program for active recovery with highly active 55, 60 and 65 percent of maximum heart rate, respectively. Groups acting Cunningham test began to test blood lactic acid in four stages [before the activity, immediately after the activity, 5 and 20 minute period recovery]. The measurement was done by a hand lacto - meter. The mean amount of blood lactic acid during resting time in four groups and also immediately after the activity was not significant, but 5 minutes after recovery as well as 20 minutes after recovery difference between groups was significant [P<0.001]. Mean blood lactic acid 20 minutes after recovery of passive group was significantly higher and that of group with 60 percent maximum heart rate was significantly lower [P<0.001] than other groups. Also the rate of the decrease in lactic acid level within 5 to 20 minutes after recovery in group with 60% maximum heart rate was significantly more than group 55%. The rate of decrease with group 65% maximum heart rate was shown to be significantly more than group 55% with maximum heart rate [p<0.001]. Our findings showed that active recovery from supramaximal exercise had a better effect than passive mode in reducing blood lactate levels in male athletes. Moreover, active recovery with a rate of 60 percent of minimum heart rate had a better effect than those of 55 or 65% maximum heart rate

[Epidemiology of smoking among adult women population of Semnan province, Iran]

Smoking is a known cause of systemic disorders such as bronchogenic carcinoma and cardiovascular diseases. The aim of this cross-sectional study was to estimate prevalence of smoking [cigarette, water pipe and pipe] in women aged 30-70 years in Semnan province in Iran. This epidemiologic cross-sectional study was conducted among 2104 women who were 30-70 years old in province of Semnan, Iran between October2005 and February 2006. Multistage cluster sampling was performed and subjects were selected from rural and urban populations. Data were analyzed by Chi-square test and p-values <0.05 were considered statistically significant. The overall prevalence of smoking in women aged 30-70 was 2.0% [95% Confidence Interval: 1.4-2.6%]. 2.5% of rural and 1.8% urban were smokers [P=0.270]. Prevalence of smoking in under 40, 40-49, 50-59 and >/= 60 years were 0.4, 2.4, 2.8 and 4.2, respectively [P=0.001]. 4.1% of illiterates, 1.6% of primary, 1.5% of intermediate, 0.4% of high school were smokers [P=0.001]. Prevalence of smoking in Semnan, Damghan, Garmsar and Shahrood were 1.3, 3.2, 0.7 and 2.4% [P=0.034], respectively. None of them were pipe smokers. 26.9% non-cigarette smokers were passive smokers. Overall, 28.9% of Semnan province adults, aged 30-70 years, were active smokers or passive cigarette smokers. The findings showed that prevalence of active or passive smoking in Semnan province in women adults aged 30-70 years is high. Given the strong positive relationship between smoking and various diseases, a comprehensive community-based health educational and interventional program is essential for reducing smoking and its detrimental consequences among woman population in Semnan province. Given the essential information about the harmful effects of passive and active smoking to woman with old ages and low educational levels, particularly who living in Daemghan, would be a valuable way for reducing destructive consequences of smoking

[Influence of basolateral amygdala lesion on the inhibitory effects of propranolol on voluntary exercise- induced enhancement of learning and memory

The beneficial effects of physical activity and exercise on brain functions such as improvement in learning and memory are well documented. In a recent study, we have found that blockade of beta-adrenergic receptors by propranolol attenuates an improvement of learning and memory by exercise. However, the anatomical sites of propranolol actions are not known. The aim of this study was to determine the role of Basolateral amygdala [BLA] in the inhibitory effects of propranolol on the beneficial effects of exercise on learning and memory. In order to block the beta-adrenergic receptors, male mice were received the beta-antagonist propranolol [10 mg/kg], before each night of five consecutive nights of exercise. The BLA lesion was made by electrolytic lesion [2mA, 2 s]. Learning and memory were tested on the Morris water maze task using a two-trials-per-day for five consecutive days. A probe trial was performed two days after the last training day. Our results showed that propranolol reversed the exercise-induced improvement in learning and memory in rat. This effect was not blocked by the BLA lesion. However, lesion of the BLA alone blocked exercise-induced enhancement of learning and memory. These findings indicate beta-adrenergic receptors located outside the BLA may mediate the effects of exercise on learning and memory. Also, the BLA play an important role in the mediating the effects of physical activity on learning and memory

Effects of aminoguanidin on the neuropathic behavioral responses of chronic constriction injury model in rat

Previous studies have shown that different mechanisms are involved in neuropathic pain. Increasing nitric oxide [NO] in the location of injury may be an effective factor in neuropathic pain which, in turn, acts through increasing membrane permeability. The aim of this study was to examine the effects of aminoguanidin, a specific inhibitor of inducible nitric oxide synthetase [iNOS] on neuropathic pain behaviors. Male Wistar rats [200-300 gram] were used. Chronic constriction injury [CCI] in the rats were produced by four loosely ligation that the distance between them is 1 millimeter before the triple branching of sciatic nerve. Two weeks later, the animals were tested for thermal hyperalgesia and mechanical allodynia. Aminoguanidine were injected [I.P] 60 min before test in doses of 75, 150 and 300 mg/kg. Our studies showed CCI induced neuropathic pain in all rats. All doses of aminoguanidin [75, 150, 300 mg/kg] significantly reduced mechanical allodynia and thermal hyperalgesia in compared with CCI group. Moreover, the effect of aminoguanidin on thermal hyperalgesia at dose of 300 mg/kg was significantly higher than two lower doses. According to findings of this and other studies, aminoguanidin has an important influence in reducing neuropathic pain. This effect, at least in part, is mediated through inhibition of iNOS. Additionally, an inhibition of di-aminoxidase or anti oxidative effects may be contributed to inhibitory effects of aminoguanidin on neuropathic pain. Thus, further investigations can determine the mechanism of aminoguanidin effects in neuropathic Pain. Findings of this study open a new window for synthesis of new drugs for management of neuropathic pain in clinic

Peripheral injection of dexamethasone modulates anxiety related behaviors in mice: an interaction with opioidergic neurons

Stress and anxiety initiates a cascade of biochemical and endocrine event which results in behavioral and electrophysiological effects in both animals and humans. In this study, we investigated the effects of dexamethasone [DEX], as a synthetic glucocorticoid, and its interaction with opioidergic system on anxiety related behavior in mice. Young adult male mice were used in this study. A standard elevated plus-maze was used to determine anxiety levels in animal. Different doses of DEX [0.1, 0.5, 1, 2 and 10 mg/kg, SC] or vehicle was injected 30 min before of evaluation. Naloxone [1 and 2 mg/kg, IP] was injected 5 min before the DEX [0.5 and 1 mg/kg] administration. Results indicated that DEX at doses of 0.5 and 1 reduced and in dose of 10 mg/kg increased anxiety related behaviors significantly [P < 0.05 in all cases]. Also pretreatment of naloxone at doses of 1 and 2 mg/kg attenuated the effects of lower doses of DEX on anxiety related behaviors. Finding above indicated that peripheral administration of glucoc orticoids induces biphasic effects on anxiety related behaviors: anxiolytic effects in lower doses and anxiogenic effects in a high dose. Data also revealed an involvement of opioidergic system in anxiolytic effects of glucocorticoids

[Evaluation the role nitric oxide in corticosterone effect's on anxiety behaviors in mice]

Many evidence indicated that action of glucocorticoid receptors can modulate anxiety behaviors and these effects probably mediated by nitric oxide [NO] system. Thus, in this study, we investigated interaction between corticosterone and NO on anxiety behaviors in mice in elevated plus maze [EPM]. In this experimental study male albino mice [25-30 g] were used. A standard EPM was used to determine anxiety behaviors. Two behavioral measures were used that include of the percentage of time spent in the open arms and the ratio of open arm entries to total entries during 5 min. Animals received IP injection of L-Name 30 mg/kg as an inhibitor or L-Arginine 50 mg/kg as a synthesis of NO or saline 60 min and corticosterone [1, 2.5, 5 mg/kg] 30 min before of evaluation. Analysis of data indicated that corticosterone at doses of 1 and 2.5, but not 5 mg/kg significantly reduced anxiety behavior in mice [P < 0.05]. Also pretreatment of L-Name potentiate but injection of L-Arginine had inhibition of corticosterone effects [P < 0.05]. This study revealed that glucocorticoid induces anxiolytic effects and these effects probably potentiate by NO inhibitor and reduced by NO synthesis. Therefore, it seems that there are interaction between of glucocorticoid and NO system for control of anxiety behaviors

role of morphine dependence on the level of anxiety in rat

The effects of acute and chronic exposures to opiate drugs on anxiety process are controversial. Acute morphine injection showed the beneficial effects on anxiety. Morphine withdrawal induced severe anxiety response in morphine dependence rats. Whereas, the effects of chronic administrations of morphine on anxiety process are less studied. Furthermore, this study was designed to assess the role of morphine dependence on the level of anxiety in Rat. In this experimental study, Twenty male Wistar rats [250-300 gr] were made dependent by chronic administration of morphine in drinking water that lasted at least 21 days. Control groups received only sucrose in their water. This study utilized the elevated plus-maze model to evaluate anxiogenic-like behavior in rats. Four fundamental behavior patterns were recorded for 5 minutes: the time spent on open arms, the number of entries into open arms, stretched-attend posture and defecation. Immediately after test, the locomotor activity of each animal was tested by using an automated activity monitor system. The data were analyzed by independent t-test and two-way analysis of variance [ANOVA]. Finding indicated that the time spent on open arms and the numbers of entries into open arms were significantly shorter in morphine dependence group than control group [P < 0.05]. Also, the numbers of stretched-attend posture and defecation were significantly higher in morphine group [P < 0.05]. Whereas, there were no significant differences between groups in locomotor activity. This study showed that dependent rats may rapidly predispose anxiogenic- like effects in stressful conditions and without the effect on motor activity