Tehran University Medical Journal

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Thyroid scintigraphy has been helpful in detecting and evaluation of thyroid nodules. Sodium pertechnetate Tc-99m is the most commonly used radionuclide for thyroid imaging because of its general availability, favorable dosimetric characteristics and low cost. But, there are reports of occasional disparity in isotope uptake in lesions compared with radioiodide. In order to determine percentage and clinical significance of this disparity, we screened 101 patients with solitary functioning nodules using sodium pertechnetate TC-99m in comparison with subsequent Iodine-131 scan in research institute for nuclear medicine. We conclude that sodium pertechnetate TC-99m is a reliable radiotracer for the detection and evaluation of thyroid nodules and there is no need for the subsequent Iodine-131 scan.

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Food, it's production and preserving has been one of the most important problems in human life. Limitation of production due to climatic, geographic and papulational situations and conservation due to providance and prosecting for solution of one of the most fundamental human needs, has been discussed much. Difference between the lands, temperature, humidity and rainfall on one hand and texture and accumulation of papulation on the other hand, not only has limited the amount and kind of food production but also has improved the preserving methods as much as possible. Extra production in fertile lands and confirmed need for receiving food in deserts and dry areas, makes the need of exchanging and transfer of food inevitable because of economic and ethical matters and sanitation of food. Avoidance of being contaminated and resistance against decay seems very important and vital. So process of preserving and conserving of eaw or cooked food became a fundamental problem. In previous 200 years, many advanced methods have been designed for preserving food in which the role of conserving and packing in vital often. Because of industrial production, conserved food have a great influence on sanitation of people nutrition, and herefor the rate of diseases from consumption of contaminated food has been reduced in industrial countries and the tensancy of people to use conventional food has been decreased gradually. Because of high cost of industrial conserved food production some people produce conserved foods in the way which is not hygienic. That may have a high risk when ingested. In this article we discuss about unwarranted conserved foods productions.

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Introduction: Inter-hospital transport constitutes one of the important parts of the emergency system in every country.

Materials and methods: To determine the outcome of requested CCU beds from the medical emergency headquarters in year 2000 by the hospitals affiliated to Tehran university of medical sciences, we have reviewed retrospectively 2688 clinical files of patients for whom a request for an empty CCU bed in other hospitals had been sent to the medical emergency headquarters. The main measure was the success rate of being admitted to CCU in other hospitals.

Results: On the whole 68.5 percent of requests were followed by a CCU admission to other hospitals. Using logistic regression method, variables including season of the year, shift diagnosis of the patient and the original hospital were shown to be related with the success rate. Conclusion: Increasing the number of available CCU beds and providing the centers with the necessary equipment is of high priority in hospitals located in city of Tehran.

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Background: Epidural injection of the drugs such as opioids has rather been a successful method in controlling post operative pain.

Materials and Methods: In a clinical trial study, 50 Female patients, in a range of 20-40 years old and ASA class I, who were scheduled for gynecologic operation were investigated. They were randomly divided in two groups. Before induction of general anesthesia, an epidural catheter was placed for each patient. Sixty minutes after the end of operation, a 15-ml solution containing 50-microgram clonidine was injected through the epidural catheter in the first group. In the second group, a similar volume solution containing 50- microgram fentanyl was injected. The catheter was removed after all the patients were followed for 4 hours and their pain was assessed by VAS (Visual Analogue Scale) method.

Results: Our findings revealed that the clonidine group had more intense pain however they had fewer complications than the opioid group.

Conclusion: We concluded that although clonidine might act as an analgesic drug, but epidural injection of a single dose of 50 microgram of the drug could not be effective enough for postoperative analgesia.

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Background: Cerebral palsy is the term used to describe a movement disorder though to be the result of nonprogressive brain damage. Due to damage to CNS, it is associated with articulation disorder and abnormal feeding reflex. Lack of oral function control and coordination following feeding reflex disorders. Articulation disorders are seen in most of the cerebral palsied patients.This research aimed to determine the relationship between feeding reflexes and articulation in cerebral palsy (spasticchildren).

Methods: This study was cross sectionally carried out on 52 children with cerebral palsy, 5 to 10 yrs old, in rehabilitation centers and private clinics. The information related to feeding reflexes was collected through direct observation of patient and evaluation of sound articulation through phonetic information test.

Results: Statistical analysis carried out by SPSS and chi-square and fisher exact tests. Abnomal chewing and tongue reflex are more prevalent than other feeding reflexes.The relationship between lip reflex and articulation of p/m/r/y/f/č and chewing reflex with articulation of/z/š/ is meaningful. The relationship between biting reflex with articulation of /z/j/l/š/ is meaningful. The relationship between tongue reflex and rooting reflex with articulation of sound is not meaningful.

Conclusion: With regard to the result of this research, it can be suggested that in children with cerebral palsy following feeding reflex disorders, abnormal posture during speech occurs that could have effect on articulation.

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Background: Autosomal-dominant polycystic kidney disease (ADPKD), a common hereditary disease, is characterized by the progressive development and enlargement of multiple cysts in both kidneys, and typically resulting in end stage renal disease (ESRD) by the fifth decade of life. Post-transplant diabetes mellitus (PTDM), a common complication after transplantation with an incidence rate of 2.5-20%, is associated with poor graft and patient survival. In few studies, PTDM has been more frequent in ADPKD transplanted patients. In the present study, we investigated whether there is any association between PTDM and ADPKD in our patients.
Methods: In this prospective study, 140 non-diabetic and nonsmoker successfully transplanted patients (27 ADPKD and 113 non ADPKD patients) were enrolled during three years. Both groups were matched for age, sex, body mass index (BMI), duration of renal replacement therapy before transplantation and also immunosuppressive protocols after transplant. Post-transplant diabetes mellitus was defined as Clinical Practice Guidelines advocated by Canadian Diabetes Association. All patients were followed for 12 months.
Results: PTDM occurred in 11.1% of ADPKD patients and in 13.1% of control group which was statistically insignificant (P > 0.05). The development of PTDM in ADPKD group was not related to sex, age, and hypertension, duration of renal replacement therapy before transplantation, BMI and serum creatinine levels (P > 0.05).
Conclusion: Post-transplant diabetes mellitus appears not to be associated with autosomal-dominant polycystic kidney disease as an etiology of end stage renal disease.

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Background: The Fontan operation is the definitive operation for palliation of complex congenital heart disease with single –ventricle physiology. The use of the extra cardiac conduit has recently been gaining popularity. The purpose of this study was to compare the outcomes of extra cardiac conduit Fontan procedure (off-pump technique) and that of traditional technique (lateral tunnel technique) in which cardiopulmonary bypass is routinely used.
Methods: Forty one patients in different age groups underwent extra cardiac conduit Fontan procedure between April 2001 and December 2004. Data were collected from ICU sheets, files and during follow up visits. Under general anesthesia and through median sternotomy, using two temporary decompressing shunts, superior vena cava implanted on right pulmonary artery and a conduit interposed between transected inferior vena cava and main pulmonary artery. Fenestration was done in almost all patients and previous shunts were closed if there were any.
Results: Of our patients, 13 were female and 28 were male. Mean age of the patients was 11.1 years (SD=7.8).In 24.4% of cases Fontan procedure was done as the first palliative surgery and in 75.6% of them there was previous history of palliative procedures. In 6 patients (14.6%) we were constrained to use cardiopulmonary bypass which was predictable or necessary in 50% of cases. There was no reoperation due to post operative bleeding. Two cases suffered from prolonged plural effusion. Our in-hospital mortality was 9.8%. During 2-24 months follow up, we found two cases who were in NYHA functional class II and one case in functional class I.
Conclusion: Extra cardiac conduit Fontan procedure could be used in a safe way. The results of this study were comparable and even in some cases better than that of the traditional technique.

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Background: MSCs have been isolated from a variety of mammals by the plastic adherence method. However, this method can be problematic due to the unwanted growth of hematopoietic cells and non-MSCs. The potential of MSCs to differentiate along multiple lineages is the key to the identification of stem cell populations in the absence of molecular markers. In the present study, we describe a homogeneous population of MSCs from mouse bone marrow isolated using an improved plastic adherence method that employs frequent medium change (FMC) at the initial hours of harvested bone marrow cell culture.
Methods: Balb/c mice were sacrificed and whole bone marrow cells were aspirated from the femur and tibia and then cultivated in six-well plates. After 3-4 hours of culture, old medium was removed and fresh medium was added. FMC was performed every eight hours over a 72 hour period. When primary cultures became nearly confluent, the first passage was performed. These cells were then used for further examination. To investigate their mesenchymal nature, the cells were allowed to differentiate into mesenchymal lineages and examined at each passage up to the tenth passage for surface antigens by flow cytometry.
Results: We achieved purified populations of fibroblast-like cells in the two weeks after culture initiation. The cells were capable of differentiating into osteocytes and adipocytes. Isolated MSCs were reactive to the CD44, Sca-1, and CD90 cell surface markers. MSCs were negative for hematopoietic surface markers such as CD34, CD11b, CD45, CD31, CD106, CD117 and CD135.
Conclusions: This protocol provides an efficient isolation of homogeneous populations of MSCs from mouse bone marrow.

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Background: Cerebral palsy (CP) is a group of nonprogressive motor impairment syndromes with potentially different risk factors and causal pathways which is caused by damage in the very young brain. The etiology of CP is mostly unknown and the prevalence has not decreased in comparison to past decades, although many advances have occurred in obstetric and neonatal care. In fact, it seems that the prevalence might have even increased in term infants. The aim of this study was the evaluation of cerebral palsy risk factors in Iran to compare them with other countries.
Methods: In this case-control study, all one to six years old children who were referred to a rehabilitation center from Shahid Beheshti child-health-care centers during the years 2007–2008, with documented cerebral palsy for evaluation of perinatal and neonatal risk factors were enrolled in the study, with matched controls.
Results: 112 in the case and 113 in the control group were studied. The main factors associated with CP, were: preterm delivery, neonatal and postnatal seizures, Apgar score of zero to three at twentieth minute after birth, low birth weight, and multiple gestations. The majority of infants with CP were born at term and only 37.8% before 37 weeks.
Conclusions: Preterm birth, hypoxic-ischemic encephalopathy and low birth weight were the independent predictors of CP in this population.

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Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background: The effect of ischemia/reperfusion (I/R) injury on kidney has been under investigation for many years. But the changes in liver function and oxidative stress status in renal I/R injury is not well known. Recent studies suggest a crosstalk between liver and kidneys. The aim of the present study was to assess liver changes after induction of various degrees of renal I/R injury.
Methods: This is an experimental study conducted on 20 male rats that were obtained from animal house of Physiology Department. Twenty male rats were subjected to either sham operation or ischemia (30, 45 and 60 min) followed by 60 min reperfusion periods. Blood samples were drawn post-operatively and plasma creatinine, BUN, ALT and AST were measured. Hepatic glutathione (GSH) and FRAP (ferric reducing antioxidant power) levels and the concentration of IL-10 and tumor necrosis factor (TNF) -alpha were evaluated.
Results: Both 45 and 60 min ischemia followed by 1h reperfusion periods resulted in significant increases in plasma creatinine (11.1±1.7mg/dl and 1.24±0.07mg/dl vs 0.55±0.15mg/dl, p<0.05) and BUN (34±3.85mg/dl and 35.0±2.81mg/dl vs 23.75±1.1mg/dl, p<0.05). These rats showed a significant decrease in liver GSH as well as significant increase in TNF-a & IL-10 concentrations.
Conclusion: Renal ischemia causes changes in liver function and oxidative stress status. A minimum of 45 min ischemia is needed to study the effects of renal injury on liver as a remote affected organ.

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Background: Fever in neutropenic patients is a medical emergency which may happen in patients undergoing chemotherapy. The definition of neutropenia varies from institution to institution but is usually defined as an absolute neutrophil count (ANC) < 500 cells/l or < 1,000 cells/l with a predicted nadir of < 500 cells/l. Bacterial and fungal infections are the most important in neutropenic patients. Viral infections with agents such as herpes simplex virus and cytomegalovirus are common but less than other pathogens. Case presentation: We report a patient with fever & neutropenia following cytomegalovirus infection during chemotherapy course for breast cancer. Conclusion: Although fever and neutropenia after cytomegalovirus infection is not very common but prompt diagnosis and treatment of this disease reduces the mortality and morbidity associated with cytomegalovirus. For this reason, screen testing for CMV infection in high risk patients including patients with cancer and preemptive therapy in patients with viremia, for prevention of CMV disease could be considered as a strategy for prevention of CMV infection.

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Background: Patients with chronic renal disease, if not treated appropriately, will be usually terminated into an irreversible stage known as End Stage Renal Disease (ESRD), the final stage of kidney disease. End stage renal disease patients cannot excrete the appropriately potassium ion through the kidney. Among the crystalloid solutions, normal saline is devoid of potassium so it is used in a widespread manner in renal transplant patients. High doses of this solution may cause hyperchloremic metabolic acidosis that is accompanied by extracellular potassium shift and impaired splanchnic perfusion. The aim of this study was to assess the effects of two types of solutions, normal saline vs. lactated ringer in these patients during the perioperative period. Methods: In a double blind clinical trial, 108 patients were randomly assigned in two groups (54 in each), while were assimilated regarding all aspects except for the type of the crystalloid solution. Age, weight, duration of the surgery, total volume of the infused crystalloid, central venous pressure and sex were all assessed. Results: The two groups were the same regarding the results gained for pre- and post- operative parameters. Follow up assessments did not show any difference between the two groups regarding above variables. Conclusions: The results of this study demonstrated that both of the crystalloid solutions assessed, normal saline and lactated ringer solution, are safe for using in patients undergoing surgical operation and there is not a risk of hyperkalemia in renal transplant patients receiving lactated ringer. This study was performed on live kidney transplants and the results were not applicable to cadaver transplants.

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Background: Infection with Taenia saginata or taeniasis is an uncommon parasitic infection in Iran with a prevalence rate of 2-3% and it is more seen in the northern parts of the country. Epigastric pain, nervousness, dizziness, nausea and loss of appetite may be the only presenting symptoms but secondary appendicitis, acute intestinal obstruction and necrosis of the pancreas are its serious and rare complications. Case presentation: A 62-year old woman was admitted to Imam Khomeini Hospital with signs of acute abdomen. She had a past history of infection with hydatid cyst and its subsequent surgery, eight years ago. At the time of admission, she suffered from persistent abdominal pain and loss of appetite for two years. Despite having the epidemiological evidence of working along the banks of rivers contaminated with human sewage and working on farms fertilized with human waste and presence of signs hinting at the disease, parasitic infection had not been considered in its diagnosis. Conclusion: Although signs and symptoms of taeniasis are non-specific but a complete history, physical examination and detailed patient notes, especially by considering epidemiological factors, are very important to the early diagnosis of taeniasis

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The combinations of antiretroviral (ARV) drugs have proven effective in controlling the progression of AIDS, but these benefits can be compromised by drug resistance. Thus, drug-resistance testing has become an important tool in the management of HIV-infected individuals.1 Drug resistance develops when mutations in the HIV virus proteins occur due to amino acid substitutions.2 Drug resistance testing is done in two ways: phenotypic test and genotypic test.3 In the first method, virus proliferation is measured in the presence of different concentrations of the drugs. In the second, the genetic structure of viral genome sequences are investigated.4 Although, the first case of HIV infection in Iran was identified 23 years ago (1988), there is still no study published on its drug resistance. The main purpose of this study was to determine the prevalence of drug resistance mutations in patients with HIV/AIDS attending Imam Khomeini Hospital in Tehran. The secondary objectives of the study were to determine the frequency of drug resistance to specific drugs such as nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitors (PI). We collected plasma samples from 25 patients with HIV/AIDS and immunological failure. After the extraction of the viral RNA from plasma, genomic sequencing was performed. Finally, the data for determining drug resistance were analyzed by the Stanford HIV Drug Resistance Database (http://hivdb.stanford.edu) software. Out of the 25 patients under study, 20 were male (80%) and five were female (20%). Routes of HIV transmission were: 56% by needle sharing among injecting drug users (IDUs), 20% through sexual contact, 12% through blood transfusions and 12% by unknown routes. High-level drug resistance for ARV drugs included: 24% to NRTIs, 28% to NNRTIs and zero percent to PI drugs. In addition, 15 patients had been infected with genotype A and 10 patients with genotype B of the virus subtypes. More than half of the patients (56%) had HCV co-infection and 44% had prison histories. Overall, the prevalence of drug resistance was 28% which is lower to those of other countries which range from 30% to 90%. Among NRTI drugs, 24% had high-level drug resistance to Lamivudin while no resistance was witnessed against Tenofovir. Among NRTI drugs, 8% had high-level and 68% had low-level resistance to Stavudine. Among NNRTI drugs, 24% and 28% of the patients showed high-level resistance to Efavirenze and Nevirapine, respectively, although the resistance rate in the present study was much lower in comparison to similar studies in China, Venezuela and Chile with respective resistance rates of 61%, 38% and 84%. In this study, no resistance was seen against PI drugs, while the resistance rates in other countries, such as Venezuela, Chile, Brazil and the U.S. have been respectively reported to be 47%, 45%, 45% and 41%.5 With higher genetic barriers than NNRTI drugs, and lack of resistance to them, PI drugs can be used effectively in health care systems in triple drug regimens. With a compliance rate of 32% in our study, 2NRTI+PI combination seems to be preferable to 2NRTI+NNRTI combination for the treatment of HIV/AIDS patients.

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Background: Bone Marrow Transplantations (BMT) are limited by low CD34+ cell counts in umbilical cord blood (UCB) and these cells need to be expanded for success in such procedures. To achieve this goal, ex vivo expansion of hematopoietic stem cells (HSCs) by enhancing their self-renewal activity on demineralized bone matrix (DBM) scaffold coated with mesenchymal progenitor cells (MPCs) and unrestricted somatic stem cells (USSCs) was recommended. TGF-b pathway is a key inhibitory factor for HSCs self-renewal. In this study ex vivo expansion and downregulation of TGF-b pathway were simultaneously performed.

Methods: USSC cells were isolated from UCB and then coated on DBM scaffold as a feeder layer. UCB CD34+ cells were isolated from UCB by magnetic activated cell sorting (MACS) method and were transfected by siRNA against TGFbR2 in two-dimensional (2D) and three-dimensional (3D) cultures by co-cultivation with USSC. TGFbR2 expression levels were evaluated by quantitative real-time PCR. Cell count and flow cytometry were performed and clonogenic activity was evaluated.

Results: Ex vivo expansion of CD34+ cells was significantly enhanced (41±0.7 folds) by TGFbR2 downregulation, especially in 2D than 3D cultures. Finally, 2D culture showed less TGFbR2 expression levels and higher increase in the percentage of CD34 markers by flow cytometry assay.

Conclusion: The 3D siRNA delivery system would be of lower efficiency in contrast to 2D settings where the cells have less freedom and are in more contact with the feeder layer.

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Background: Nausea and vomiting is one of the most important complications in chemotherapy. Serotonin and dopamine are important neurotransmitters in nausea and vomiting. It seems that oxygen therapy and increase oxygen saturation can cause decrease these neurotransmitters. The aim of this study was to investigate the relationship between arterial oxygen saturation (SaO2) of patients and chemotherapy-induced nausea and vomiting. Methods: A descriptive-analytical study was performed in Koosar Hospital in Semnan, Iran, from 19 September 2013 to 25 April. At first, SaO2 of 30 patients in three periods (pre, during and post chemotherapy) were measured. Severity of nausea and vomiting in three days after chemotherapy was measured with an index of nausea, vomiting and retching (Rhodes Index). Also during chemotherapy, anxiety and depression of patients was measured with Hospital Anxiety and Depression Scale (HADS). Results: In this study thirty patients were evaluated. Most of them were women (66%) with mean age of 55.07±11.9 years old. The most common cancer in patients was breast cancer (46.7%). Mean of SaO2 was 92.1%±3.4 that was not significant difference during the chemotherapy. Mean of nausea and vomiting severity in first day of chemotherapy was (3.27±5.5), in second day was (4.5±6.2) and in third day was (7.2±8.7). The Pearson correlation coefficient did not show the relationship between oxygen saturation with severity of nausea and vomiting (P>0.05). Although severity of anxiety of patients was significant relationship with nausea and vomiting in third day (P=0.03). Conclusion: In this study there was no significant relationship between oxygen saturation and severity of nausea and vomiting, but anxiety of patients was related to nausea and vomiting in third day. Chemotherapy-induced nausea and vomiting was more common in third day and it seems that further research is needed for relationship between oxygen saturation and nausea and vomiting in third day of treatment.

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Growing and developing are influenced by genetic, social and environmental factors and it's most important and initial phase step is formed of the early life of the fetus and infant. According to the world health organization, the incidence of preterm birth and low birth weight are increasing in most countries that most of it related to developing countries. Low birth weight (LBW) and preterm birth are one the most important causes of death in the world and therefore are considered as one of the major health problems that can affect growing and developing so that it can threaten public health. Advances in medical technology in recent decades at intensive care unit, increased survival of premature infants and high-risk specialist care is needed, but failed, to reduce the complications of premature birth but it couldn’t reduce complications of preterm birth. There is also an increased recognition of the potential disconnect between perinatal outcomes and long-term outcomes. The administration of oxygen and postnatal steroids are prime examples of interventions that may have immediate positive effects but negative long-term effects. Many premature babies will be encounter with mobility problems, cognitive, neurosensory impairments, cerebral palsy, cognitive and language delays, neuromotor developmental delay, blindness and hearing loss, behavioral and psychosocial disorders, learning difficulties and dysfunction in scholastic performances in the future. These disadvantages appear to persist into adulthood and therefore have broad implications for society. Without a doubt, one of the tragedies of the world is people with physical or mental damage caused by premature birth, many of these disorders are not early diagnosed and the prediction of long term complications of infants discharged from the NICU is difficult. Although nourodevelopmental follow-up of these babies is a necessary part of the neonatal assessment but there is no standard process for it. The present review article aims to introduce the care process and tools that is used for following-up these babies, also introduces the application of screening tools for neuro-developmental care.

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Background: Depression, as one of the most prevalent and disabling disorders in the world, has a complex and yet not well-known pathophysiology. Genetic, hormonal, neurotransmitter, inflammatory and neurodegenerative theories are all responsible. Studies show that depression leads to structural changes in the hippocampus, prefrontal cortex, amygdala, anterior cingulate, and basal bodies. Hippocampal volume loss is observed due to the death of nerve cells, neurons, and glial cells, and reduced neurogenesis. The hippocampus is a part of the limbic system. The limbic system is the area in the brain that is associated with memory, emotions, and motivation. The limbic system is located just above the brain stem and below the cortex. Despite the many studies related to the reduced hippocampal neurogenesis in depressed patients, no study has compared the amount of neurodegeneration between the left and right hippocampus. In this study, we compared neurodegeneration levels in the right and left hippocampus of the rats. Methods: Twenty male Sprague-Dawley rats that were purchased Razi Institute, Karaj, Iran, were evaluated in the study. This study was conducted in cellular and molecular center in Iran University of Medical Sciences, from June 2012 to June 2013. Half of them had unpredictable chronic mild stress (UCMS) for 21 days to develop depression. The forced-swimming test (FST) was used to measure the immobility time (IB), a symptom of depression. One week after the behavioral test, the rats were prepared for transcardial perfusion. Then, paraffin fixed brain was excised and the hippocampus was prepared for Nissl staining. All above-mentioned procedures were performed for the control group too except inducing UCMS. Results: Our results increased IB in the UCMS group, 68.8 second in stress group and 15.1 second in control group. Nissl staining showed prominent neural degeneration in the hippocampus of the rats in the UCMS group. Comparison of the left and right hippocampal cells revealed that the right hippocampus (mean= 49.166) was more vulnerable to stress than the left hippocampus (mean= 76.6). Conclusion: Our study showed different manifestations of depression after UCMS. It showed that UCMS could lead to mental depression. This study showed that the right hippocampus was more sensitive to stress than the left hippocampus. In fact, UCMS resulted in depression. The study showed that the right hippocampus was more sensitive to stress than the left hippocampus. Therefore, the main function of the right hemisphere, which is adaptation to the new environment, is disturbed more.

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Background: Hematopoietic stem cell transplantation (HSCT) is a therapeutic approach in treatment of hematologic malignancies and incompatibility of bone marrow. Umbilical cord blood (UCB) known as an alternative for hematopoietic stem/ progenitor cells (HPSC) for in allogenic transplantation. The main hindrance in application of HPSC derived from umbilical cord blood is the low volume of collected samples. So, ex vivo expansion of HPSCs is the useful approach to overcome this restriction. Synthetic biomaterials such as nanofibers is used to produce synthetic niches. The aim of this study was the ex vivo expansion of hematopoietic stem cells on biocompatible nanofiber scaffolds. Methods: This study was done at Tarbiat Modares University from November 2012 to June 2013 and was a research study. Umbilical cord blood CD133+ hematopoietic stem cells were separated using MidiMacs (positive selection) system by means of monocolonal antibody (microbeads) CD133. Flow cytometry was used to assess the purity of cells. Cell culture was done on plate (2 Dimensional) and fibronectin conjougated polyether sulfone nanofiber scaffold (3 Dimensional). Colony assay test was used to asses the ability of colonization of cells. Results: Cell count analysis revealed the expansion of hematopoietic stem cells in cell culture plate (2D environment) and on nanofiber scaffold (3D environment) after 2 weeks. Expansion of cells in 2D environment was greater than 3D condition. Colony assay test revealed that the colonization ability of cells decreased after 2 weeks, but this decrease was lower in scaffold culture than plate culture. Conclusion: This study demonstrated that umbilical cord blood CD133+ hematopoietic stem cells can expand on fibronectin conjugated polyether sulfone scaffold and we can use this system for expanding of cells in vitro situation.