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1.
Induction of diabetes by Streptozotocin in rats   总被引：1，自引：0，他引：1  
The objective of this study is to induce experimental diabetes mellitus by Streptozotocin in normal adult Wistar rats via comparison of changes in body weight, consumption of food and water, volume of urine and levels of glucose, insulin and C-peptide in serum, between normal and diabetic rats. Intra-venous injection of 60mg/kg dose of Streptozotocin in adult wistar rats, makes pancreas swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes mellitus in the 2–4 days. Induction of experimental diabetes mellitus is indeed the first step in the plan of purification of pancreatic Langerhans islet cells of normal rats for transplanting under the testis subcutaneous of experimentally induced diabetic rats. Streptozotocin induces one type of diabetes which is similar to diabetes mellitus with non-ketosis hyperglycemia in some animal species. For induction of experimental diabetes in male adult rats weighted 250–300 grams (75–90 days), 60mg/kg of Streptozotocin was injected intravenously. Three days after degeneration of beta cells, diabetes was induced in all animals. The diabetic and normal animals were kept in the metabolic cages separately and their body weight, consumption of food and water, urine volume, the levels of serum glucose, insulin and C-peptide quantities in all animals were measured and then these quantities were compared. For a microscopic study of degeneration of Langerhans islet beta cells of diabetic rats, sampling from pancreas tissue of diabetic and normal rats, staining and comparison between them, were done. Induction of diabetes with Streptozotocin decreases Nicotinamide-adenine dinucleotide (NAD) in pancreas islet beta cells and causes histopathological effects in beta cells which probably intermediates induction of diabetes. In this study, we used Streptozotocin for our experiments in induction of experimental diabetes mellitus. After Induction of diabetes, consumption of food and water, volume of urine and glucose increased in the diabetic animals in comparison with normal animals, but the weight of body and the volume of insulin and C-peptide decreased in the diabetic animals. Sampling and staining of pancreas tissue of diabetic and normal rats showed that the Langerhans islet beta cells of diabetic rats have been clearly degenerated. In three days, Streptozotocin makes pancreas swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes. It also changes normal metabolism in diabetic rats in comparison with normal rats. Consumption of water and food, volume of urine, serum glucose increases in diabetic animals in comparison with normal rats but the levels of serum insulin, C-peptide and body weight decreases.  相似文献   
2.
The Multidimensional School Anger Inventory–Revised (MSAI-R) is a measurement tool to evaluate high school students' anger. Its psychometric features have been tested in the USA, Australia, Japan, Guatemala, and Italy. This study investigates the factor structure and psychometric quality of the Persian version of the MSAI-R using data from an administration of the inventory to 585 Iranian high school students. The study adopted the four-factor underlying structure of high school student anger derived through factor analysis in previous validation studies, which consists of: School Hostility, Anger Experience, Positive Coping, and Destructive Expressions. Confirmatory factor analysis of this four-factor model indicated that it fit the data better than a one-factor baseline model, although the fit was not perfect. The Rasch model showed a very high internal consistency among items, with no item misfitting; however, our results suggest that to represent the construct sufficiently some items should be added to Positive Coping and Destructive Expression. This finding is in agreement with Boman, Curtis, Furlong, and Smith's Rasch analysis of the MSAI-R with an Australian sample. Overall, the results from this study support the psychometric features of the Persian MSAI-R. However, results from some test items also point to the dangers inherent in adapting the same test stimuli to widely divergent cultures.  相似文献   
3.
Many motile bacteria are propelled by the rotation of flagellar filaments. This rotation is driven by a membrane protein known as the stator-complex, which drives the rotor of the bacterial flagellar motor. Torque generation is powered in most cases by proton transit through membrane protein complexes known as stators, with the next most common ionic power source being sodium. Sodium-powered stators can be studied through the use of synthetic chimeric stators that combine parts of sodium- and proton-powered stator proteins. The most well studied example is the use of the sodium-powered PomA-PotB chimeric stator unit in the naturally proton-powered Escherichia coli. Here we designed a fluidics system at low cost for rapid prototyping to separate motile and non-motile populations of bacteria while varying the ionic composition of the media and thus the sodium-motive force available to drive this chimeric flagellar motor. We measured separation efficiencies at varying ionic concentrations and confirmed using fluorescence that our device delivered eightfold enrichment of the motile proportion of a mixed population. Furthermore, our results showed that we could select bacteria from reservoirs where sodium was not initially present. Overall, this technique can be used to implement the selection of highly motile fractions from mixed liquid cultures, with applications in directed evolution to investigate the adaptation of motility in bacterial ecosystems.  相似文献   
4.
Insulin injection is the main way to combat against insulin-dependent diabetes mellitus effects. Today in some laboratories in the world, the investigators are trying to find some treatments for this disease with insulin-secreting pancreatic islet cells transplantation. Donor tissue in each step of work was prepared from 36 adult male wistar Rats weighted 250–300 grams (75–90 days). Transplantation was done in rats after 2–4 weeks induction of diabetes with 60mg/kg of streptozotocin injection by intravenous method. Encapsulation of pancreatic islet cells allows for transplantation in the absence of immunosuppression. This technique that is called “immunoisolation” is based on the principle that transplanted tissue is protected for the host immune system by an artificial or natural membrane. In this study, the levels of insulin, C-peptide and glucose in diabetic rats have been reached to normal range as compared to un-diabetic rats in 20 days after transplantation of islet cells, so that testis is immunoisolated place for islet cells transplantation. Inside the testis subcutaneously and intrapretoneally implantation of pure islet cells graft, that is a natural immunoisolation method, rapidly and permanently normalized the diabetic state of streptozocin-administered animals.  相似文献   
5.
Carboxylate-modified gold nanoparticles (GNPs) were synthesized in a simple one-step process based on the reduction of tetrachloroauric acid by aspartic acid in water. GNPs were identified by UV–Vis spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy. Conjugation of protein molecules with functionalized nanoparticles was performed through electrostatic interaction. The GNP–protein conjugates were characterized by gel electrophoresis. The interaction between functionalized GNPs and protein molecules lead to conformational transition of protein structure after conjugation of protein with GNPs. This process was investigated by fluorescence spectroscopy and circular dichroism spectroscopy.  相似文献   
6.
In the present study, paclitaxel was archaeosomed to reduce side effects and improve its therapeutic index. Carriers have made a big evolution in treatment of many diseases in recent years. Lipid carriers are of special importance among carriers. Archaeosome is one of the lipid carriers. Paclitaxel is one of the drugs used to treat breast cancer which has some unwanted side effects despite its therapeutic effects. Archaeosomes were extracted from methanogenic archi bacteria and synthesized with a certain ratio of paclitaxel in PBS. The mean diameter of archaeosomal paclitaxel was measured by Zeta sizer instrument, Drug releasing of archaeosomal paclitaxel was examined within 26 h which results showed that the most drug releasing occurs during first 3 h. The cytotoxicity effect of archaeosomal paclitaxel on breast cancer’s cell line was evaluated by MTT assay which results showed that the cytotoxicity effect of archaeosomal paclitaxel on breast cancer’s cell line is more than that of the standard paclitaxel formulation. The results indicated that new drug delivery of paclitaxel using archaeosome, increases the therapeutic index of the drug.  相似文献   
7.
Cisplatinum (Cispt) is an anti-cancer drug with a low level of solubility. One of Cispt’s solvents is dimethyl sulfoxide (DMSO) which can be substituted with chlorine of drug as Cispt’s solvent. Applying such a solvent in biological studies is impossible due to intense reduction in activity. On the other hand, it is specified that Cispt’s stability is increased in aqueous media by increasing sodium chloride (NaCl) concentration up to 0.9 %. Consequently, we intended to study the effect of DMSO on cytotoxicity of Cispt in presence of sodium. MTT assay was employed to study cytotoxicity effect of Cispt + NaCl + DMSO and Cispt + DMSO on G-292 cell line. Cytotoxicity in dilutions of 300 and 9 (p < 0.01) of Cispt in Cispt + NaCl + DMSO formulation was equal to 78 and 7 %. These values were estimated 79 and 18 % for Cispt + DMSO formulation and 79 and 24 % for free drug. IC50 values demonstrated reduction of 45 % in cytotoxicity of Cispt in Cispt + DMSO formulation. Studying chemical structure of Cispt and Cispt dissolved in DMSO showed that NaCl cannot inhibit inactivating effect of DMSO on Cispt and effect of this solvent on Cispt is independent from presence of NaCl. Results represented that using NaCl does not result in stability and keeping cytotoxicity properties of Cispt in DMSO. Findings suggest more studies for using DMSO as a solvent of Cispt.  相似文献   
8.
The objective of this study is to induce experimental diabetes mellitus by streptozotocin in normal adult Wistar rats via comparison of changes in body weight, consumption of food, volume of water, urine and levels of glucose, insulin and C-peptide in serum, between normal and diabetic rats. Intra-venous injection of 60 mg/kg dose of streptozotocin in 250–300 g (75–90 days) adult Wistar rats makes pancreas swell and causes degeneration in Langerhans islet β-cells and induces experimental diabetes mellitus in 2–4 days. For a microscopic study of degeneration of Langerhans islet β-cells of diabetic rats, biopsy from pancreas tissue of diabetic and normal rats, staining and comparison between them, were done. In this process, after collagenase digestion of pancreas, islets were isolated, dissociated and identified by dithizone method and then with enzymatic procedure by DNase and trypsin, the islet cells changed into single cells and β-cells were identified by immune fluorescence method and then assayed by flow-cytometer. Donor tissue in each step of work was prepared from 38 adult male Wistar rats weighted 250–300 g (75–90 days). Transplantation was performed in rats after 2–4 weeks of diabetes induction. In this study, the levels of insulin, C-peptide and glucose in diabetic rats reached to normal range as compared to un-diabetic rats in 20 days after transplantation of islet cells. Transplantation was performed under the cortex of testis as immunoisolated place for islet cells transplantation.  相似文献   
9.
Regarding that the breast cancer is the most prevalent disease among women, paclitaxel, an anti-cancer drug, could be used in treatment of this disease. As paclitaxel has adverse effects, it was used of nanoliposome drug delivery technology in order to reduce adverse effects and improve drug efficacy. Certain ratios of phosphatidylcholine, cholesterol and paclitaxel were synthesized to prepare nanoliposomal paclitaxel. Using Zeta sizer device, the mean diameter of nanoliposomal paclitaxel was obtained 421.4 nm and its encapsulation efficiency was 91.3 %. By dialysis, drug release in nanoliposome paclitaxel formulation within 28 h was studied which was 5.53 %. This study showed that cytotoxicity effect of nanoliposomal paclitaxel is more than that of the standard form.  相似文献   
10.
Flow cytometry has been employed as a method to study homogeneity of isolated islet subpopulations. After collagenase digestion of rat pancreas and elutriation of tissue fragments, islets were isolated and dissociated, and cells were analyzed and sorted according to their low forward angle light scattering properties by using automated flow cytometry. A standardized procedure was developed for the preparation of rat islet cell grafts for purification of islet cells. In this process, after collagenase digestion of pancreas, islets were isolated, dissociated, identification by dithizone method and then with enzymatic procedure by DNase and trypsin, the islet cells changed into single cells and beta cells were identified by immunofluorescence method and then assayed by flow cytometry. Methods have been developed for the preparation of suspension of viable rat pancreatic islet cells and their analysis and sorting in the fluorescence activated cell sorter (FACC IV, Becton Dickinson, Sunnyvale, Ca). Flow cytometry of these cells indicated that there were 91% of beta cells in cell suspension. Most of the exocrine particles were lost during digestion. Purified endocrine islet cell grafts were prepared by pure beta-cells, without endocrine non-beta cells. The purified aggregates were devoid of endocrine non-beta cells and damaged cells.  相似文献   
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