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Material and methods: This is a Double blind Randomized clinical trial study which was performed on 66 children of 2-7 years of age who had been referred for first time, for nonbrain non-liver elective surgery (class 1 Anesthesia). This study was designed to define the efficacy of oral ketamine on Anxiety and Agitation and crying of children after separation from these parents, toleration of Anesthesia mask and IV needle. Sleeping before Anesthesia and entry into the operating room samples were divided in to two groups, cases and control. 5mg/kg of ketamine plus 0.2cc/kg of fruit juice was given to the case group while only 0.2cc/kg of fruit was given to the control group 30 minutes before the operation.
Results: Our results showed that 78.8% of children in the case group did not cry when they were separated from their parents and 78.8% of them did not show any resistance. 34.4% of children in the case group showed no response and 59.4% also had low response. Only 6.1% of children in the control group had no response while 78.8% of them had responses such as intense body movements and pulling of hand. 69.7% of the case group were cooperative when putting on the anesthesia mask while 75.8% of the control group refused to wear the mask, 81.8% of the children in the case group were asleep before Anesthesia while all of the children in the control group were awake and uneasy.
Conclusion: These findings indicate that ketamine can be used as a preanesthetic drug to decrease the anxiety and fear of children and to calm them before their transfer to the operating room.

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Introduction: Therapeutic use of D-penicillamine is associated with several side effects. Proteinuria is the most common side effect of it, often due to membranous glomerulopathy. In this article we have reported a case of D-penicillamine induced focal segmental glomerulonephritis with systemic sclerosis. Case: In This article, we have presented a patient who had been under treatment with D-penicillamine and complicated by nephrotic range proteinuria resulting from focal segmental glomerulonephritis. Proteinuria was resolved one month after discontinuation of D-penicillamine without any additional treatment. She had no finding in favour of renal crisis of scleroderma. Conclusion: Such this pathologic form of renal involvment (FSGN) resulting from D-penicillamine has not been reported in the literature yet.

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Introduction: Bone mineral density (BMD) measured by dual energy x-ray absorbtiometry (DEXA) is widely used in management of patients with osteoporosis. Factors which are specific to machine or operator, can influence the accuracy and precision of BMD estimations. In this study we investigated the effect of leg rotation and femoral neck on densitometry of femur. Materials and Methods: In a before and after, interventional study on 200 women between 30-70 years old, without metabolic bone diseases, densitometry was done first in standard position and then in 15ْ rotation of leg from standard position and then after changing femoral neck angle from 90ه to 80ْ in relation to central femoral neck axis . Density of femoral neck, ward triangle, greater trochanter, shaft of femur and total hip was measured and data was analyzed by means comparison test. Results: External rotation of leg by 15 ه from the customary position, increased the average BMD in femoral neck, wards area, trochanter and shaft (p<0.001, p<0.04, p<0.001, p<0.008 respectively).While no significant change was observed in average BMD of total hip. Change of femoral neck area angle from 90 ه to 80 ه in relation to central femoral axis decreased BMD in femoral neck (p<0.001), and significantly increased BMD in wards triangle, trochanter, shaft and total hip (p<0.001, p<0.001, p<0.001, p<0.04 respectively). Conclusion: Malrotation of hip can be an important confounding factor when interpreting serial BMD values. Regarding the less effect of malpositioning on BMD of total hip, this area may be prefered for assessment of densitometry result.

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Introduction: Thalassemia patients are transfusion dependent and the consequence of these repeated transfusions is hemosiderosis. Therefore these patients need iron chelator drugs. Desferioxamine is an iron chelator drug that its route of administration is subcutaneous which is very difficult for patients. Deferiprone (L1) is an oral iron chelator drug that is easy to use for thalassemic patients. The aim of this study is the efficacy assessment of L1 on ferritin level in Arak city during 6 months. Materials and Methods: In this before and after clinical trial study, 33 patients underwent treatment with L1, with the dose of 75 mg/kg/day.The mean of ferritin level in patients was measured before and 6 months after receiving L1. Data was analyzed using paired t-test. Results: The mean age of patients was 17.2±1 years (10-34 years old). The mean ferritin level before administration of L1 was 1881±257 mcgr/l and after administration of the drug was 2495±384 which had no significant difference. Side effects were leukopenia (3%), rise of ALT (35%) and increase of AST (60%) which were all transient. Conclusion: Although the level of ferritin increased after the treatment with L1, but there was no significant difference and it seems that the drug can have a good effect in decreasing iron. All of he patients in this study have received the drug for 6 months. Therefore we need other studies with longer duration in order to assess the efficacy of Deferiprone.

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Introduction: Oral Ketamine is used as a low side effect analgesic in comparison with opioids, in different pain syndromes. This study is designed to evaluate the effect of oral Ketamine in renal colic treatment. Materials and Methods: In this clinical trial study 104 patients with renal colic, hospitalized in emergency department, were divided in to two groups by Random block design. Group B received Pethidine (1 mg/kg up to 100 mg) and placebo, and group A received Pethidine with the same dose and Ketamine (0.5 mg/kg). All patients were assessed for pain by using VAS chart, for nausea by a 0-3 scale and for the number of vomiting at baseline and 1, 2 and 3 hours after taking drug. The results were analyzed by t-test. Results: Average pain score and vomiting in all times and nausea score in one and three hours after receiving drugs were reduced significantly in patients who took Pethidine and Ketamine comparing patients who took Pethidine and placcbo(p < 0.05). Conclusion: Regarding the significant effect of Ketamine in reduction of pain, nausea and vomiting without side effects, it is possible to use Ketamine as an adjuvant drug in treatment of renal colic and to reduce narcotic dosage.

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Background: Pain following propofol injection was reported between 28- 90 %. Ketamine have lesser cardiovascular depression effect and also local anesthetic effect. In this study effect of ketamin were analyzed when it given before propofol injection. Methods and Materials: In a randomized double blind clinical trial selected 120 ASA I, II Ptients with 15-65 years old. They were candidated for elective surgery, in half of the patients 100 µg/kg ketamine in 2 ml volume and in another half, 2 ml distilled water were given before propofol injection. Severity of injection pain was evaluated according to 4 scale criteria (none, mild, moderate, or severe) fifteen seconds after injection of 25% of the calculated dose of propofol. Heart rate (HR) and noninvasive blood pressure were recorded before and after propofol injection, immediately and 3 minutes after intubation. The data were analysed by Mann Whitney U, Pooled t-Test and the Chi-squared test. Results: Pain was not sensed in 51.56% and 75% of control and case groups respectively. In cases group showed little decrease in systolic and diastolic pressures after anesthetic induction (p=0.012 and p=0.005). There were upper diastolic pressures after intubation (p=0.00) and 3 minutes after intubation (p=0.000). During intervention heart rate changes had not significant difference between two groups. Conclusion: Ketamine pre-treatment was an effective method in reducing pain and providing hemodynamic stability after propofol induction.

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Background: Muscle mass is known to be a significant predictor of bone mineral density (BMD), and myostatin is a negative regulator of muscle growth. The aim of present study was investigate the effects of resistance training on bone mineral density and serum myostatin in healthy young men. Methods and Materials: In this clinical trial thirty young men were assigned to resistance training (n=15) and control (n=15) groups. The training group participated in 6 mounths of progressive whole-body resistance training. Total body fat, lean body mass, total body BMD, femoral neck BMD and L2-L4 spine BMD were determined by Dual-Energy X-ray Absorptiometry (DEXA) before and after 6 mounths of resistance training. Serum level myostatin measured by enzyme immnoassay. Results: Resistance training caused significant increases in chest press (52.36±6.36 vs 62.20±8.96 kg), leg press (135.24±13.77 vs 146.91±17.66 kg), lean body mass (61.00±0.96 vs 62.58±2.08 kg) and femoral neck BMD (1.115±0.078 vs 1.131±0.088 g/cm2), whereas myostatin were decreased (102.91±10.18 vs 94.03±13.93 ng/ml) (P<0.05). Total body BMD and L2-L4 spine BMD did not change with 6 months resistance training. Conclusion: A 6 month resistance training program increases muscle mass, power and improves BMD of the femoral neck in young men, and myostatin inhibition may play an important role in increasing BMD which is induced by resistance training.

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Background: Postoperative shivering is a common problem with multiple complications. This study was compared effect of low doses of Ketamine with Pethidine for controlling postoperative shivering. Methods and Materials: This clinical trial was done on 189 elective cesarean section with ASA class I or II who had postoperative shivering. Patients with grade 2 or higher were divided in three groups and were injected 0.3mg/kg Ketamine and 0.5mg/kg Pethidine intravenously. In 5th and 10th minutes after injection, they were investigated for shivering intensity. Results: After 5 minute of injection drugs rate and intensity of shivering in Pethedine group was less than ketamine group. Ketamine with 0.5 mg/kg was more effective than 0.3mg/kg dose of it and Ketamine(p=0.041). In group with 0.5mg/kg dose of Ketamine, rate and intensity of postoperative shivering was more reduce than group with 0.3mg/kg of it in recovery(p=0/007). In Pethedine group rate and intersity of shivering was more reduce then 0.5mg/kg dose of Ketamine(p<0/001). This demonstrated that Pethedine is more effective than Ketamine. Conclusion: Although 0.5mg/kg dose of Ketamine has considerable effect on control of shivering but Pethedine is still a better choice for this side effect.

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Background: Salvia staminea, belonging to lamiaceae family, has positive effects on the nervous system and possesses anti-oxidant and anti-inflammatory effects. Hence, this study was conducted to determine the neuro-protective effects of salvia and its total ethanol extract on spinal cord motoneurons in Wistar rats. Materials and Methods:In an experimental trial, 54 male Wistar rats were divided into nine groups of six: Control, compression, treatment A (ethanol extract of root in 25, 50, and 75 mg/kg doses), treatment B (aqua extract of root in 25 and 50 mg/kg doses), treatment C (aqua extract of leaves in 50 mg/kg doses), and treatment D (ethanol extract of leaves in 75 mg/kg doses). In compression and treatment groups, 28 days after inducing impairment in α motoneurons, sampling of the left leg sciatic nerves was done in the rats. Following tissue passage, 7 micron cuts were obtained and painted with blue toluidine. Neuralgia motoneurons count was, then, carried out through steriology and dissector methods. Results: Neuron number density in the rats treated with 50 mg/kg doses of total aqua and ethanol extracts of leaves and 75 mg/kg dose of ethanol extract of root showed significant differences in comparison to that of the compression group (p<0.05). Conclusion: The results of this study prove the neuroprotective effects of these extracts on neuralgia motoneurons of spinal cord.

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Background: Pain following tonsillectomy is common in children, and its elimination due to its subsequent complications is essential. Therefore, this study was conducted with the aim of obtaining the best method of administering ketamine for reducing pain following tonsillectomy with the greatest efficiency and the least side effects. Materials and Methods:This study was a double-blind clinical trial which was conducted on 92 children, aged 3-9, who had been admitted for tonsillectomy. The patients were randomly divided into oral ketamine and ketamine injection groups (each containing 46 patients). Thirty minutes before the operation, all the patients were given apple-juice ketamine injection group received normal apple juice without ketamine, whereas the oral ketamine group received 5mg/kg ketamine with the apple juice. Three minutes before tonsillectomy, 0.5 mg/kg ketamine was injected to the peritonsillar area in ketamine injection group while the same volume of saline was injected to the oral ketamine group. Data were registered, gathered, and, then, analyzed using Wilcoxon, Man Whitney, and t tests. Results: Demographic data and blood pressure before and after the operation did not have significant differences in the 2 groups. In terms of the duration of operation time, a significant difference was observed between the two groups the operation time in the ketamine injection group was shorter (p=0.006). Also, pain score in the ketamine injection group was less than the oral ketamine group. Conclusion: Ketamine is effective in reducing the pain after tonsillectomy operation. Peritonsillar injection of ketamine is more effective than its oral usage.

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Background: Multiple sclerosis (MS) is a demyelinating disease of central nervous system which has different clinical manifestations. Noticing the role of vitamin B12 in synthesis of myelin tissue and the existence of different views about its pathogenesis and causes, we decided to evaluate B12 serum levels in MS patients. Materials and Methods: In a case-control study, 40 patients with definite clinical diagnosis of MS and 80 traumatic patients hospitalized in the emergency ward of Vali-asr Hospital of Arak (the control group) were chosen. The level of blood vitamin B12 was measured for all the subjects through the same type of kit and clinical checklist. Data were analyzed through t-test. Results: The mean vitamin B12 serum level in case and control groups were, respectively, 295±133.3 pg/dl and 257.73±91.3 pg/dl which did not indicate a significant difference(p> 0.05). However, in terms of the type of clinical manifestations, the mean vitamin B12 serum level in MS patients showed at least one sensory, motor, or sphinctery symptom lower than the control group. This difference turned out to be significant(p< 0.05). In terms of MRI findings, patients with brainstem and vertebra plucks respectively had the maximum and minimum vitamin B12 serum levels. Conclusion: Although a significant difference was not observed between the mean vitamin B12 serum levels, based on the significant decreases in the serum levels of this vitamin in some of the patients with subtypes of MS, further studies with larger sample sizes and over longer periods of time are suggested.

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Background: Lead (Pb) brings about a variety of cognitive, mental, renal, and blood system disorders by inducing oxidative stress. The aim of this study is to compare blood and urine parameters in the workers exposed to Pb and zinc (Zn) with those in the control group. Materials and Methods: An analytical cross-sectional study was conducted with a total number of 134 subjects. The case group included 67 male workers with the age range of 22-65 who had at least worked a minimum of one work shift for two years in the Zn-Pb mine located in the southwest of Arak, Iran. Control subjects consisted of 67 farmers of a village near the mine who had no history of occupational exposure to Pb, Zn, and other metals. Mental disorders were evaluated through the standard Scl-90-R while cognitive disorders were evaluated via the Mini Mental Status Examination (MMSE). Results: The mean level of blood and urine parameters did not reveal significant differences between the two groups. The mean scores of physical complaints, anxiety, and aggression scales were significantly higher in the case group than the control (p<0.05), whereas the mean scores on MMSE did not reveal a significant difference between the two groups. Conclusion: The oxidative stress of Pb led to mental disorders as a result, the mine workers suffered from more psycho- pathology and are in need of greater care. Due to the impacts of Pb and Zn, the proper use of safety equipments and taking daily showers can reduce the risk of absorption of toxic agents and their subsequent hazards for workers.

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Background: Postoperative pain brings about undesirable effects such as medical complications, increased healthcare costs, and the need for opioids administration. The aim of this study was to determine the effect of low dose (0.15 mg/kg) ketamine in comparison with the placebo on postoperative pain and analgesics consumption after cesarean section. Materials and Methods: In a randomized clinical trial, 120 women undergoing elective cesarean section were randomly divided into case and control groups. Ketamine (0.15 mgkg-1) or an equal volume of normal saline were administered intravenously immediately after initiating spinal anesthesia to the case and control groups, respectively. The anesthesia and surgery techniques were the same for both groups. Data were analyzed using SPSS version 11. Results: Means of age in the case and control groups were 28.85±4.81 and 28.87 ±5.62 years, respectively. Analgesics consumption, pain scores, homodynamic signs, drowsiness of the mothers, and the neonates’ Apgar scores after cesarean section were similar in both groups and no significant differences were found between them (P>0.05). The mean of postoperative arterial pressure in the early hours in the ketamine group showed a significant decrease compared to the placebo group (P>0.03). The means of the first time of request for analgesics after surgery in the ketamine and placebo groups were 99.75±68.88 and 96.1±52.59 minutes, respectively (P>0.05). Conclusion: It seems that the administration of 0.15 mg/kg dose of ketamine (0.15mg/kg) does not have a significant impact on decreasing the postoperative pain in cesarean section. Therefore, in order to obtain the desirable analgesic effects of this drug, further studies should be conducted with greater doses of this drug and its use in combination with other opioids.

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Background: Pain is a complex problem, which can affect patients' physical and psychological condition. Inadequate postoperative pain control has adverse effects on the patients' physiological, metabolic and mental condition. Adding new supplement will increase the duration of analgesia. This study aimed to comparison of intratechal neostigmine and midazolam in increasing the time of postoperative analgesia. Materials and Methods: In this randomized double blind clinical trial, 60 patients with ASA class Ι, II who were candidate for elective colporrhaphy surgery under spinal anesthesia were randomly divided into 3 groups of 20 patients. All patients received hyperbaric lidocaine 5% and groups I received 1 mg midazolam, groups II received 50 μg Neostigmine and groups III received 0.5 cc normal saline additionally. Then according VAS pain score, postoperative painless duration and pain score were compared between groups by running SPSS software. Results: Mean of painless duration in the Midazolam, Neostigmine and control groups were 98.4±18.2, 74.5±32.6 and 64.5±9.9 minutes respectively which was significantly longer than in Midazolam group (p<0.001). The mean dose of requested analgesia in first 24 hours after surgery was significantly lower in Midazolam group (p<0.001). Conclusion: Inthrathecal midazolam and Neostigmine as a complementary medication to lidocaine 5% can increase painless duration in colporrhaphy surgery and midazolam is more effective than Neostigmine. Key Words : midazolam & Neostygmine , Spinal anesthesia, painless time , colporrhaphy

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Background: Post-anesthetic shivering is the most common cause of patient discomfort during recovery with a prevalence of 5 to 65%. Post-anesthetic shivering can increase pain, oxygen consumption, and cardiac output. The aim of this study was to compare the efficacy of various classes of drugs for preventing post-anesthetic shivering.

Materials and Methods: In this double-blind clinical trial, patients undergoing elective laparotomy were randomly divided into six groups, 40 each. The patients, respectively, received hydrocortisone, ketamine, tramadol, magnesium sulfate, pethidine, and normal saline. All patients were observed for body temperature and shivering for 20 minutes after arrival to recovery room.

Results: Seventy patients in the pethidine group did not have shivering upon arrival to recovery room which was significantly higher than other groups (&chi2=0.00002). Also, the patients in the pethidine group did not shiver 10 and 20 minutes after arrival to recovery room that was significantly lower than other groups.

Conclusion: According to the results, it can be concluded that pethidine is more effective than other drugs in prevention of post-anesthetic shivering.

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Background: It is well known that morphine influence learning and memory processes. The Nucleus accumbens (N.ac) which has an important role in reward participates in morphine-induced impairment of memory retention. Considering the cholinergic system is involved in the effects of morphine on learning and memory, in the present study, the effects of intra-N.ac injections of acetylcholine receptor antagonists alone or with morphine on memory retention and morphine-induced memory has been investigated in rats.

Materials and Methods: In this original research animals were bilaterally cannulated in the N.ac and a step-through passive avoidance task was used for the assessment of memory retention .

Results: Post-training subcutaneous administration of morphine dose dependently decreased the learning and induced amnesia. The administration of the same dose of morphine as pre-test treatment induced state-dependent learning. Pre-test intra- N.ac administration of atropine, scopolamine and mecamylamine in different doses alone cannot affect on memory retention. While, pretest intra- N.ac injection of these drugs before the administration of morphine dose dependently inhibited morphine state-dependent learning. The level of statistical significance was set at p<0.05 .

Conclusion: The processes of learning in animals can be affected by morphine and the opioids produce state-dependent learning. Moreover, it can be concluded that inactivation of the muscarinic and nicotinic acethylcoline receptors in the N.ac are involved in mediating morphine state-dependent learning.

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Background: This study aimed to examine the antibacterial effect of Polyamidoamine-G4 dendrimer on Escherichia coli, Enterobacter cloacae, Bacillus subtilis and Staphylococcus aureus.

Materials and Methods: In this experimental study, the antibacterial effects of Polyamidoamine-G4 dendrimer were studied by disc diffusion and micro-dilution method. Different concentrations of Polyamidoamine-G4 inoculated onto blank disks and were placed in Mueller-Hinton agar media. Zone of inhibition was investigated by bacterial inoculation according to the McFarland standard 0.5. Minimum inhibitory concentration and minimum bactericidal concentration of Polyamidoamine-G4 dendrimer were determined by micro-dilution method in nutrient broth culture.

Results: Zone of inhibition in concentration 500 &mug/ml of Polyamidoamine-G4 dendrimers for Escherichia coli, Enterobacter cloacae, Bacillus subtilis and Staphylococcus aureus were 14, 0, 35 and 29mm, respectively. Concerning the Zone of inhibition in gram negative bacteria with gram positive ones was p<0.05 and had significant difference. The minimum inhibitory concentration of Polyamidoamine-G4 dendrimer for Escherichia coli, Bacillus subtilis and Staphylococcus aureus were 1250, 2.5, and 1 &mug/ml, respectively. The minimum bactericidal concentration of Polyamidoamine-G4 dendrimer belonged to Escherichia coli, Bacillus subtilis and Staphylococcus aureus were 2500, 5 and 5 &mug/ml, respectively. Polyamidoamine-G4 dendrimer had not bacteriostatic and bactericidal effects on Enterobacter cloacae.

Conclusion: According to the results, Polyamidoamine-G4 dendrimer can eliminate Escherichia coli, Staphylococcus aureus and Bacillus subtilis effectively. It is suggested in the rest of this study that the probable toxicity of nanostructured compounds examined in drinking water and, economic studies is done for synthesis and their applications in case of prevention of using.

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Background: Heat shock proteins (HSP) can act as a cellular protection by facilitating reconstruction of denatured proteins. The aim of this study is evaluation of protective effects of glutamine consumption on HSP70 and cortisol response.

Materials and Methods: In this experimental study, 28 soccer players divided into 4 groups: control (n=7), supplement (n=7), exercise (n=7) and exercise supplement (n=7). Supplements (glutamine) and placebo (Dextrin) to a 0.5 gram per kg of body weight and volume of 5 ml per kg of body weight one hour prior to the exercise protocol was used. exercise protocol include a 3-stage 20-minute run at 80% of maximum heart rate and rest 5 minutes. Blood samples of basal (after 12-14 hour overnight fasting), post exercise, and 90 minutes after exercise were gathered and HSP70 of serum and cortisol were measured with Elisa and RIA respectively. Data were analyzed with multivariate repeated measures (MANOVA) at p&le0.05 level.

Results: There was significant difference in HSP70 amounts between supplement group and exercise supplement group compared to the control group (p&le0.09, p&le0.019) and also supplement group with exercise supplement group (p&le0.032). Also there was significant difference Between post exercise and 90 min after exercise stages compared to basal stage (p&le0.08, p&le0.06) and between post exercise and 90 min after exercise (p&le0.030). In cortisol amounts between basal and 90 min after exercise stages (p&le0.026) there was significant difference.

Conclusion: Glutamine sitimulate of HSP70 induction and combination of supplement with exercise has a great HSP70 response thus athletes who wish to compete or have intense exercise, glutamine consumption is recommended.

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Background: Delayed muscular soreness after resistance exercises or eccentric trainings is probably because of muscle damage and injury. Nutrition by playing a crucial role in both protein synthesize and catabolism can influence the extent of muscle injury. The objective of this study was to assess the effect of single portion of Glutamine supplement consumption on injury indices of muscle after a session eccentric resistance exercise.

 Materials and Methods: This study used a randomized, double blind design that consisted of 80 volvnteer non-athletic males (aged 22.2±2.2 years, height 175±5 cm, weight 71.64±9 kg, body mass index 23.2±2.2 kg/m2, and body fat 17.5±2.4%). A total of 40 participants were divided randomly into 2 groups, supplement group (receiving 0.1 g/kg Body weight/day Glutamine) and placebo group (receiving 0.1 g/kg Body weight/day Maltodextrin). Serum keratine kinase (CK) was determined by photometric method, muscle pain and knee joint range of motion were measured using, respectively, a standard scale of PAS and goniometer before, 24 and 48 hours after a resistance test involving knee flexion.

Results: Glutamine supplement consumption caused no significant differences in CK levels reduction in none of the measured times, but it reduced the muscle pain at the times of 24 and 48 hours in comparison with the placebo group. In addition, the knee joint range of motion was significantly improved at 24 hours after the test.

Conclusion: It seems that this dose of Glutamine supplementation can reduce the apparent signs apart from muscle injury indices reduction.

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        Background: Dendrimers are a subset of branched structures that have certain structural order. The aim of this study was to investigate the performance of Polypropylenimine-G2 (PPI-G2) dendrimers in removal of Escherichia coli, Proteus mirabilis, Bacillus subtilis and Staphylococcus aureus from aqueous solution .

        Materials and Methods: In this experimental study , initially dilution of 10³ CFU/ml was prepared from each strain of bacteria . Then , different concentrations of dendrimers (0.5, 5, 50 and 500 µg/ml) was added to water . In order to determine the efficiency of dendrimers in removal of bacteria, samples were taken at different times (0, 10, 20, 30, 40, 50 and 60 min) and were cultured on nutrient agar medium . Samples were incubated for 24 hours at 37 ° C and then the number of colonies was counted .

       Results: By the increasment of dendrimer concentration and contact time , the number of bacteria in aqueous solution decreased. In times of 40 , 50 and 60 minutes, and the concentrations of 50 and 500 µg/ml, all kinds of bacteria in aqueous solution were removed . 0.5 µg/ml of dendrimer concentration had not effect in reducing the number of Escherichia coli and Proteus mirabilis . The effect of dendrimer on gram-negative bacteria was weaker than gram-positive bacteria.

       Conclusion: Results of this study indicated that PP I -G2 dendrimer is able to remove Escherichia coli , Proteus mirabilis , Staphylococcus aureus and Bacillus subtilis in aqueous solution. However, using dendrimers can be considered as a new approach for drinking water disinfection but it requires further wide range studies.