[Evaluation of platelet-rich plasma effects on femoral cancellous bone defect healing in rabbit]

Background: Platelet-rich plasma [PRP] is an autologous product having a high concentration of growth factors well known to stimulate different tissues healing. This study was made to determine the effect of PRP on healing of femoral cancellous bone defect in rabbit

Materials and Methods: The experiment was conducted on 16 male adult New Zealand white rabbits. The animals were divided into the control group and the treated group including 8 rabbits in each group. Under general anesthesia, using a dental drill, a hole 4 mm in diameter 5 mm in depth was made in the inner aspect of the medial condyle of left femor. In the treated group the created hole was filled with autologous PRP. In the control group, the defect was left untreated. The bone healing was evaluated histopathologically at the end of the first and the second month post surgery. In addition, the samples were assessed histomorphometrically 2 month post surgery

Results: In the control group, the defect seemed to be filled with adipose tissue including sparse hematogenic cells 1 month after surgery. A poor osteogenic activity and some osteoblasts were visible two month post surgery. In the treated group, within 1 month, a mass of osteoblasts as well as neoformed vessels occupied the gap 1 month after surgery. One month later we observed increased young bone trabeculas in addition to a more compact bone neoformation

Conclusion: We concluded that PRP with some characteristics such as ostegoenesis and osteoinduction provide a more rapid regeneration of bone defects

[Immunohistochemical study of the Effect of Calendula of_cinalis of _-catenin protein expression in experimental colon cancer]

Background: Colorectal adenocarcinoma is one of the most prevalent and treatable malignancies of the gastrointestinal tract. Recent in vitro studies have demonstrated the anticancer effect of Calendula offcinalis extract on a tumor cell line derived from colorectal cancers. The inhibitory effect of this extract ranges from 70- 100% and an in vitro study has demonstrated that Calendula offcinalis extract inhibits expression of nuclear beta-catenin protein on dysplastic colonic aberrant cryptal cells. The aim of present study was to evaluate in vivo the effect of Calendula offcinalis extract on the expression of beta-catenin protein in dysplastic colonic aberrant cryptal

Materials and Methods: In this study 20 male Wistar rats with an approximate age of 12 weeks that weighed 200-300g were assigned to two equal groups [treatment and control]. For the induction of colorectal carcinoma these two groups were given two subcutaneous injections of 1,2-dimethylhydrazine [40mg/kg] twice a week for eight weeks. Thereafter, the treatment group received Calendula offcinalis extract [200mg/kg] daily for ten weeks through gavage. The control group received normal saline by the same manner. After ten weeks of treatment with Calendula offcinalis extract, distal parts of colonic tissue were sampled in both groups. Expression of beta-catenin was assessed semi-quantitatively by four scales through immunohistochemical analysis. Significant difference between the groups was determined by the Mann-Whitney U test. Statistical significance was considered at p<0.05

Results: Immunohistochemical studies revealed that the expression of nuclear beta-catenin protein in dysplastic colonic aberrant cryptal cells was lower in the treatment group compared to the control group. The mean difference between the treatment and control groups was Significant [p <0.01]

Conclusion: The results of this in vivo study indicated that Calendula offcinalis extract has an inhibitory potential on the expression of nuclear beta-catenin protein in dysplastic colonic aberrant cryptal cells in experimental colorectal carcinoma of rats

[ effect of treadmill exercise on experimental diabetic hepatopathy in rats]

Regular exercise by increasing insulin sensitivity and improving the glucose uptake and lowering body adiposity is a powerful non-pharmacological tool for prevention and treatment of diabetes mellitus. Diabetic hepatopathy is the main cause of liver failure. The purpose of this study was to evaluate the effect of regular exercise on diabetic hepatopathy. In this experimental study, 56 wistar male rats with approximate age of 12 weeks and 200-300g weight were allocated into two equal groups of treatment and control. For induction of diabetes, these two groups were injected by streptozotocin [50 mg/kg] intraperitoneally. The treatment group was kept in normal conditions of management with regular exercise [treadmill] as 5 days a week, an hour every day, for 12 weeks. In control group, subjects have normal conditions without any physical activity and regular exercise. After 12 weeks, liver tissues were sampled in both groups and 5-6 micron tissue sections were prepared through H and E staining method. Histopathological study in control group showed hepatosclerosis, central vein perivascular cuffing of mononuclear inflammatory cells, hepatocellular degeneration, sclerosing hyaline necrosis, apoptosis, dense perisinusoidal, and periportal and perivenular fibrosis. Mild pathological changes were observed in treatment group and significant differences were observed between two groups. Treadmill exercise is capable in reduction of pathological changes and improves diabetic hepatopathy to near normal histology

[Biochemical and pathological study of protective effect of vitamin A in azathioprine - induced hepatotoxicity in rat]

Background: azathioprine [AZA] is the most widely used immunosuppressive drug for preventing graft rejection and autoimmune disease. However, the therapeutic treatment induces several side effects such as toxicity to bone marrow, pancreases, liver and gastrointestinal tract. One of the major functions of Vitamin A is to act as a natural antioxidant by scavenging free radicals. Considering the kind of Azathioprine-induced damage in Liver tissue, we decided to study the protective effect of Vitamin A against Azathioprine-induced toxicity

Materials and Methods: forty Male Wistar rats were divided into 4 groups [each group contains 10 rats]. Group 1 was control group and only took normal saline. Groups 2 and 3 were administrated daily use of Vitamin A for 7 days I.M. and Group 4 was administrated with normal saline instead of Vitamin A in same condition as groups 2and3. In the last day groups 3 and 4 were administrated with single dose of AZA, 15 mg/kg [IP]. After 24 hours, we took the animals blood and tissue samples and studied them for biochemical and pathological examinations

Results: this study showed that Azathioprine-induced damage on liver in group 3 is less than that in group 4 while the function of organ in group 3 is nearly the same as control group. Also vitamin A decreases Azathioprine-induced hepatotoxicity in rats

Conclusion: regarding importance of Azathioprine-induced damage, the usage rate of this drug in medicine, and the results of this study, we suggest that co-administration of Azathioprine and vitamin E decreases the toxicity of this drug

[Experimental study of cell death in lymphoid tissues of SPF chickens with avian influenza virus [H9N2] infection]

Influenza virus causes the cell death in animals and human beings. Cell death occurs in two manners as necrosis and apoptosis. In this study, the types of cell death in lymphoid tissues assessed in experimentally infected chickens with H9N2 avian influenza virus [A/chicken/Iran/772/2000]. In this experimental study, 20 SPF chickens aged 3 weeks were divided equally into two groups. The treatment group was infected with 0.2 ml of 1:10 dilution and 10[7.5] EID50 titer of the virus intra-nasally and the control group was treated with saline normal in the same volume. Lymphoid organs including spleen, thymus and bursa of fabricius were collected after 72 hours of treatment and tissue specimens were fixed in 10% buffered formalin. Microscopic sections with the thickness of 5-6 micron were stained by H and E method. Histopathological examination of lymphoid tissues of the experimental groups indicated necrosis, apoptosis and lymphoid depletionsin the treatment group. Apoptotic changes in the splenic tissues were significantly different between two groups [p<0.001]. There were no significant differences between two groups in terms of changes in the thymus and bursa of fabricius. However, Necrotic changes and lymphoid depletions in the splenic tissues, thymus and bursa of fabricius were significantly different between two groups [p<0.001]. This study indicates that H9N2 avian influenza virus is able to cause lymphoid tissue damages through induction of apoptosis and necrosis

[Preventive effects of growth hormone on degeneration of rabbit ovarian follicles during cyclophosphamide induced toxicity]

Cyclophosphamide [CP], an antineoplastic drug, is also widely used in treatment of a variety of diseases such as lymphomas, leukemia, neuroblastoma, ovarian carcinoma, breast cancer and auto-immune diseases. However, its use has toxic effects on different tissues of the body, for example, it causes involution and degeneration of ovarian follicles and toxicity in the ovaries. In contrast, growth hormone [GH] improves the function of most body tissues and research has shown that it leads to the increase in the number and size of the ovarian follicles. The purpose of this study was to study the preventive effects of growth hormone during cyclophposphamide induced toxicity on the ovarian follicles. In this study, 30 New Zealand white rabbits were divided into three groups containing 10 animals in each. Group 1 was the control group and only received placebo. Groups 2 and 3 were administrated 100 mg/kg body weight CP orally daily. Group 3 was also administered growth hormone 0/15 mg/Kg subcutaneously for 49 days [from 7 days before initiation of CP therapy to 14 days after the last administration of CP].The day after last administration of CP, all 30 rabbits were anesthetized by ether and ovariectomized and the number of different types of developing follicles, regressive follicles and degenerations in ovarian tissue was studied. Degeneration of follicles was observed in both groups 2 and 3, but the number of degenerated follicles in group two was more than that in group 3 which had received GH. The number of degenerated areas in ovarian tissue in group 2 was also higher than that in the other two groups. The difference between body weight and the weight of the ovaries in groups 1 and 3 was not significant, but there was a significant decrease in body weight and ovarian These results suggest that co-administration of GH can improve the function of ovary and preserve the ovary and follicles from CP induced toxicity

[Investigate the effect of regular exercise on diabetic nephropathy in rat]

Diabetes mellitus and its complications are a public health problem. Exercise is frequently recommended in the type I and type II diabetes mellitus and can improve glucose uptake by increasing insulin sensitivity and lowering body adiposity. Diabetic nephropathy has become the main cause of renal failure. The purpose of this study was to investigate the effect of regular exercise on diabetic nephropathy. In this study, fifty-six 12-week rats weighted 200-300 gr were selected and assigned into two groups [treatment and control]. Diabetes mellitus was induced by intraperitoneal injection of streptozotocin [50 mg/kg]. The treatment group were kept in normal conditions of food and place with regular exercise [treadmill] for 12 weeks, 5 days in a week, an hour every day. In control group we prepared normal conditions [food and place] without any physical activity/regular exercise. After 12 weeks renal tissues were sampled in both groups and 5-6 micron tissue section were prepared through H and E staining method. Histopathological analysis of tissue section in control group demonstrated that glomerulosclerosis, arteriolosclerosis, perivascular cuffing of mononuclear inflammatory cells, tubular cells nephrosis and hyaline cast in lumen of renal tubules and a little pathological changes in treatment group were observed. Mean deference of histopathological changes and proteinuria in two groups were significant. We demonstrated that regular exercise [treadmill] is able to reduce pathological changes and improve diabetic nephropathy disease in diabetic patients resulting in the reduction of HbA1c, oxidative stress, hyperglycemia, VLDL, expression of apoptosis regulatory gene and TGF-beta and increase insulin sensitivity, HSPG, HS, HDL, IGF and EGF