Zahedan Journal of Research in Medical Sciences
Volume:16 Issue: 2, Feb 2014

Ischemic tolerance can protect the brain against cerebral ischemia and neurodegenerative diseases. However, several studies demonstrate ischemic tolerance by various methods, the exact mechanisms of ischemic tolerance has not been clearly understood. In this study, we first studied brain ischemia-related mechanisms and then evaluated the outcomes of mitochondrial pathophysiology of ischemic tolerance in focal and full stroke animal models. In this study, mitochondrial and peroxisomal reactions are considered critical in ischemic tolerance. In rats and Syrian mice, the middle cerebral artery occlusion (MCAO) model was employed to represent cerebrovascular stroke. Ischemic tolerance exhibits different types of adaptation responses associated with a number of sub-cellular changes.Changes in the cellular non-genomic pathways are usually short and reversible; while, the consequences of genes expression are a long-term process and can lead to permanent alternations in the genes expression pattern. The ischemic tolerance can be clinically significant. Therefore, it is important to address the risks and advantages of ischemic tolerance in non-infarcted tissues such as transplanted ones.

Metallo-β-lactamase (MBLs) can hydrolyze a broad spectrum of beta-lactams, including penicillins, cephalosporins, and carbapenems. Genes encoding these enzymes are located on the plasmid that can easily be transferred to other bacteria. The aim of this study was to isolate and identify the Pseudomonas aeruginosa strains encoding VIM1 gene, in clinical samples, using the PCR technique. During a 4 month period, 100 strains of Pseudomonas aeruginosa from clinical specimens were collected. Standard tests were performed to identify strains of Pseudomonas aeruginosa. Resistance to antibiotics was examined and then the PCR was used to detect VIM1gene. In this study, the highest rates of resistance to antibiotics, amikacin and cefotaxime was observed (65% and 62%), the lowest resistance to antibiotics piperacillin (48%) and imipenem and cefepime with 55% resistance was reported. DDST method was performed for 37 strains for the MBl detection. Among the 37 isolate, 30 strains were MBL-producing with imipenem-EDTA method. Twelve strains (18%) were carriers of VIM1 gene using the PCR method. In the present study, the prevalence of strains producing MBL genes in strains of hospitals is a growing trend; correct prescription of medications can prevent the spread of resistant pathogens. It is suggested that molecular methods for rapid detection of resistance genes can be used to prevent the spread of this genes.

Chronic periodontitis is an inflammatory disease caused by environmental and genetic factors. It leads to destruction of tooth supporting tissues and may cause tooth loss. Cytokine TNF-α plays a role in the development of inflammatory lesions and development and progression of the chronic periodontitis disease. Some polymorphisms of this gene are accompanied with change in expression level. The purpose of this study was to investigate the relationship between TNF-α -308 G>A (rs1800629) polymorphism and chronic periodontitis. In this case-control study, 100 patients with chronic periodontitis and 100 normal subjects, referring to the clinic of Zahedan Dental School, were evaluated. Venous blood samples of participants were taken. DNA was extracted using salting-out technique and gene polymorphism was studied at this position using specific primers by T-ARMS PCR method. To investigate the frequency of genotypes and alleles in both groups, X2 test was employed and p<0.05 was taken to be statistically significant. The frequencies of AA, GA, and GG genotypes in the patient and control groups were, 1%, 8%, and 91%, and 0%, 16%, and 85%. The frequencies of A and G allele in patient and control groups were 5% and 95%, and 7.9% and 92.1% respectively. There was no significant difference in the frequencies of genotypes and alleles between the groups. The present study indicates that there is no association between TNF-α (-308 G>A) polymorphism and chronic periodontitis in this population.

The aim of this study was to investigate the effect of valsartan, an angiotensin II antagonist, on the function of the pituitary- gonad axis. Adult male Wistar rats (200 to 220 g) were used as experimental and control groups. The 3 experimental groups received either 100, 200, or 400 mg/kg/day valsartan in 1 ml water orally for 28 days, while a set of control group received 1 ml distilled water for the same period of time and another set received no treatment. At the end of the experimental period, blood was collected and serum was analyzed for FSH, LH, testosterone and dihydrotestosterone levels by RIA methods. There were no significant differences among FSH levels at all doses of valsartan used, while the serum LH level was decreased significantly at the maximum dose of the drug used. Serum testosterone level decreased at both the 200 and 400 mg/kg dose compared to the control, while the dihydrotestosterone level was reduced significantly at all the three dosages used. According to our founding, suggested that the effects of valsartan on serum LH, testosterone and dihydrotestosterone may be mediated through angiotensin II receptor.

Radio frequency wave (RFW) generated by base transceiver station (BTS) has been reported to make deleterious effects on liver and kidney, possibly through oxidative stress. This study was conducted to evaluate the effect of radiofrequency wave (RFW)-induced oxidative stress in the liver and kidney and the prophylactic effect of vitamin C on this organs by measuring the antioxidant enzymes activity including: glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT), and malondialdehyde (MDA). In this experimental study, thirty-two adult male Sprague-Dawley rats were randomly divided into four experimental groups and treated daily for 45 days as follows: control, vitamin C (L-ascorbic acid 200 mg/kg of body weight/day by gavage), test (exposed to 900MHz RFW) and the treated group (received vitamin C in addition to exposure to RFW). At the end of the experiment all animals were sacrificed and their liver and kidney were removed and were used for measurement of antioxidant enzymes and MDA activity. The results indicate that exposure to RFW in the test group decreased antioxidant enzymes activity and increased MDA compared with the control groups (p<0.05). In the treated group vitamin C improved antioxidant enzymes activity and reduced MDA compared to the test group (p<0.05). It can be concluded that RFW causes oxidative stress in liver and kidney, and vitamin C improves the antioxidant enzymes activity and decreases MDA.

With appearance of nano particles as an important component in modern medicine، and considering to new properties of these components، study of their effects on human health is essential. Since zinc components influences mechanisms of nociception، the aim of this study was to evaluate the effect of nano zinc oxide as a new source of zinc and important components in pharmaceutical and hygienic cosmetic production on nociception in adult female rats. Female rats were divided into groups: control (receiving saline 0. 9%) and receiving nano ZnO (0. 5، 1، and 5 mg/kg). Hot plate and tail flick tests as models of somatic acute pain were used for evaluation of the pain. The mean of latency time in paw licking and tail withdrawal respectively recorded as nociception indexes in each test for every animal. The animal numbers in each group was seven. In tail flick test، nano ZnO (0. 5، 1 mg/kg) and in the hot plate test in dose of 0. 5 mg/kg، induces significant analgesia (p<0. 05) and with increasing of dose reduced its analgesic effect. It seems nano ZnO inhibit the nociception mechanisms and these analgesic properties are more efficient in the low doses. Probably by increasing dose of nano particles aggregation phenomenon prevent of anti-nociception effects of nano ZnO.

The liver is the major target organ for aflatoxin B1 (AFB1). Ingestion of aflatoxin causes hepatotoxicty. In this study، captopril as new agent to help the hepatotoxicity induced by aflatoxin was suggested. The isolated perfused rat liver (IPRL) was chosen for evaluating hepatic function. Sixteen rats were divided randomly into four experimental groups: control، captopril، AFB1 and AFB1 + captopril. The level of glutathione content and lipid peroxidation، as marker of oxidative stress and lactate dehydrogenase (LDH)، alanine transaminase (ALT) and aspartate transaminase (AST) activities and pH of the perfusate medium were measured. There was a significant decrease in lipid peroxidation and same increase was observed in glutathione level. Treatment with captopril also modulated the enzymes activity and pH of perfusate. This study showed that captopril protects the hepatotoxicty induced by AFB1. Therefore، this drug may provide an effective new strategy to reduce of aflatoxins toxicity.

Nutmeg, Myristica fragrans Houtt, has shown anti-inflammatory properties in some studies. At present experimental study, we evaluated the effect of seed extract of nutmeg on adjuvant-induced arthritis in rats in comparison with flunixin meglumine. Experimental study was done in six groups of Wistar rats (each group 8 rats) as following: Group 1 was kept as control under similar conditions to other groups. All other rats received complete Freund''s adjuvant at dose 0.1 ml which injected under skin of foot. Group 2 was received vehicle (normal saline). Group 3 received flunixin intraperitonealy at dose of 2 mg/kg body weight of rats daily for 12 days. Group4 to 6 received extract of nutmeg at dose 100, 200 and 300 mg/kg intraperitonealy and daily for 12 days. Four rats in each group were anesthetized and blood collected for serum analysis on 12th day. The ankle joint prepared for histopathological examination. The remained rats were kept until 21th day. Levels of the cytokine TNF-α in serum was measured using ELISA kit. The serum levels of TNF-α in the group 2 were significantly increased; while nutmeg decreased the elevated TNF-α level in a dose-dependent manner but significantly with 300 mg/kg. The flunixin did not significantly decrease the levels of TNF-α. Nutmeg treated rats manifested pathological events in the ankle joints to a markedly lesser degree. Flunixin prevented pannus formation but it was ineffective in other lesions. Thus, nutmeg protected the joints against cartilage destruction and bone erosion in a dose-dependent manner.

Caffeine at high doses is a known rodent teratogen and induces limb malformations along with cleft palate in various strains of rats and mice. The teratogenic effects of some drugs can be prevented by the application of antioxidant drugs and stimulation of the maternal immune system. Also, there is some evidence that galbanum is antioxidant. Therefore, in this study, the prophylactic effect of galbanum on teratogenic effects of caffeine was evaluated. This experimental study was performed on 28 pregnant rats that were divided into four groups. Control group received normal saline and test groups received caffeine (80 mg/kg), caffeine (80 mg/kg) plus galbanum (200 mg/kg) and galbanum (200 mg/kg), intraperitonealy at 9-11th days of gestation, respectively. Fetuses were collected at 20th day of gestation and after determination of weight and length; they were stained by Alizarin red - Alcian blue method. Cleft palate incidence was 33.3%, in caffeine group and decreased to 8.3% by galbanum. The mean of weight and length of fetuses from rat that received galbanum were significantly greater than those received only caffeine. It is concluded that galbanum decreased cleft palate induced by caffeine; but its mechanism needs more details evaluation.

Ghrelin is a 28-amino-acid peptide hormone that is secreted primarily by stomach cells with lesser amounts secreted by other cells (including the hypothalamus). The aim of present study was to examine the effects of 8 weeks aerobic training with different durations on resting plasma Ghrelin levels in male rats. Fifty adult Wistar male rats (6-8 weeks old, 270±10 g) were selected and randomly divided into five groups: 30, 60 and 90 min training, sham and control groups. All experimental groups performed an 8-week treadmill running program at the same velocity at 0 gradients for 30, 60 or 90 min/day, 5 days/week. The concentration of ghrelin in blood samples was assessed after 8 weeks and 72 hours following the final training session. The ghrelin concentration was measured by ELISA. Possible statistically significant differences between groups after the exercise training intervention was determined by one way ANOVA, and LSD test was used for a post hoc analysis. Resting levels of ghrelin concentration were unchanged after training. Similarly, there was no observed change in the insulin and glucose concentrations compared with the control group. However there was a significant difference in estrogen when compared with the control group. The data suggest that body weight reduction is amplified by exercise-induced and increases in plasma estradiol and a moderate duration exercise program.

Toxoplasma gondii is one of the most common protozoan parasites in humans and animals in all countries of the world. The aim of this study was to detect Toxoplasma parasite in the brain of wild rats in Tehran using smear preparation, Giemsa staining, Intraperitoneal injection and oral administration to Souri mice. Forty rats were collected from different areas of Tehran. Smears were prepared from rat brains on glass slides and stained using Giemsa. In the second method, a cell suspension was prepared from rat brain and was given orally and injected intraperitoneally into Souri mice. In peritoneal method, peritoneum of the mice was examined for parasites. In oral method, the titer of Toxoplasma antibody in sera of Souri mice was determined using Toxoplasma IgG antibody kit and anti-mouse conjugate of Sigma company. All results were negative in Giemsa staining method. In the second method, the results were negative and no parasites were observed in peritoneum of Souri mice. In oral administration method, after ingestion of suspensions by Souri mice and measuring the IgG titer, 50% of them showed a positive titer after one month. In detection of Toxoplasma gondii, the method of smear preparation on glass slides followed by Giemsa staining, and intraperitoneal injection of brain suspensions to Souri mice are of less value in comparison with oral administration of suspensions and determining the titer of IgG in sera of Souri mice.

Since liver is a gland which has an important role in drug metabolism, the present study was conducted to evaluate the effect of a single dose and repeated administration of morphine on LFT, blood sugar and fasting insulin resistance index in fructose- fed male rats. The experiment was performed on 36 Wistar-Albino male rats, which were divided into a control (A) and three tests groups (B, C and D). The control group consumed tap water, but the test groups consumed fructose-enriched water (10%, w/v) and received null, single, and repeated doses of morphine, respectively. At the end, animals were anesthetized and blood samples were collected. Liver enzymes, insulin and insulin resistance were measured. Data were analyzed by SPSS-11, using ANOVA and Tukey tests as post hoc test. Results were expressed as mean±SD and Statistical differences were recognized significant by p<0.05. The results showed that all test groups were insulin resistant; alanine aminotransferase (ALT) and asparatate aminotransferase (AST) activity values in group D significantly increased compared to other groups while its plasma glucose and insulin values showed a significant decrease in comparison to other test groups. It seems that repeated morphine administration can affect liver function test (LFT) and fasting Insulin resistance index (FIRI) in fructose- fed male rats.

Nanoparticles are small particles which can destroy many diseases resulting from microorganisms. Due to very small size, these particles can penetrate various tissues easily like liver and many side effects. This study has compared poisonous effects of thioacetamide with silver nanoparticles on amino transferase enzymes and liver tissue in male syrian mice. In this study, mice were divided to four groups. First group or control was received food and water, second group received thioacetamide 50 mg/kg, third group received 3000 ppm silver nanoparticles and fourth group received a compound of silver nanoparticles 3000 ppm and thioacetamide (50 mg/kg). Then, blood from mice hearts was collected and liver tissue was separated for measuring, SGPT and SGOT enzymes, and also for tissue studies. Injection thioacetamide increased SGOT and SGPT enzymes in second group more significantly than group. However, nanosilver injection only increased SGPT enzyme significantly (p=0.02). According to the results of this study, silver nanoparticles and thioacetamide can damage liver cells. But destruction of hepatocytes resulting from oxidative pressure of combination silver nanoparticles and thioacetamide was more than the other groups.

Osteoarthritis is the commonest form of arthritis and is considered to be one out of ten major causes of disability in the world. The objective of present study was to investigate the effect of treadmill exercise alone and in combination with quercetin supplementation on male rats’ knee osteoarthritis. Thirty male Wistar rats (weight of 173±1 g, 8-weeks old) were randomly divided into 5 experimental groups (N=6): intact control, MIA only, training, quercetin, training plus quercetin. The Osteoarthritis model was induced by intra-articular injection of monosodium iodoacetate (MIA). Subjects then followed a moderate-intensity exercise program and quercetin supplementation for 28 days. Rats were killed after 28 days and histological assessment has been performed on their knee joints. One-way ANOVA (p<0.05) and post-hoc Tukey test was used for the statistical analysis. Histological assessment including 1- Depth Ratio of Lesions (p=0.001), 2- Total Degeneration Width (p=0.001) and 3- Significant Degeneration Width (p=0.001) demonstrated a beneficial influence of moderate exercise combined with quercetin supplementation group, but this influence was not superior than the moderate exercise alone group. This study shows that a moderate exercise program and quercetin supplementation, either alone or in combination, exert a beneficial influence on rats’ knee osteoarthritis. But it appears that moderate exercise alone has more effectiveness.

Catalase enzyme plays an important role in the anti-oxidation defense of body so it is important to measure its activity. Nowadays catalase activity measurement is performed by expensive imported kits in various scientific fields. The purpose of this study was to design a sensitive fluorimetry method for measuring catalase activity with improved sensitivity, accuracy and speed. In this study, the reaction of hydrogen peroxide with peroxidase (as a reaction accelerator) was used in fluorimetry for catalase activity measuring in serum samples in order to increase the sensitivity of the assay. The sensitivity and intra- and inter-assay accuracy, verification test, recovery and parallelism tests, comparison method and correlation and coherence investigation methods were also performed. In order to increase the accuracy and speed of reading, the assay was performed in microplates and reading was done in fluorimetry plates. The percentage of intra- and inter-assay variation coefficients were measured 3.8-6.6 % and 4.1-7.3%, respectively. Comparison of the results of mentioned method for 50 serum samples with common colorimetric method showed a good correlation (0.917). In assessing the accuracy, the recovery percent was obtained 91% to 107%. The test sensitivity was measured 0.02 IU/ml. The fluorimetry method by microplate reading has a sufficient precision, accuracy and efficiency for catalase activity measuring as well as speed of measurement. Thus it can be an alternative method to conventional imported colorimetric methods.