Induction of diabetes by Streptozotocin in rats

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.     

What do prospective students look for in higher degrees by research? A scale development study

ABSTRACT

This empirical investigation was aimed at conceptualizing, developing and validating a scale for the measurement of the quality of higher degrees by research (HDR-QUAL). For that purpose, this study specifically measured perceptions of higher degrees by research (HDR) students about the constituents of HDR quality in Pakistani tertiary education institutions. Following the 7-step process of scale development, three studies were conducted in order to develop an initial pool of scale items, establishing proposed scale validity and reliability, and assessing nomological behavior of the proposed scale. The principal component analysis with Varimax rotation method resulted in a 3-factor solution, subsequently proposing a 15-item scale. The model fit indices of measurement and the higher-order model indicated a satisfactory fit to data. Finally, the resultant three factors, i.e. financial assistance, supervisory expertise, and infrastructural support, converged into a unidimensional HDR-QUAL scale that was found positively associated with student satisfaction, thus, confirming nomological validity as well. Important policy measures and directions for future research are proposed at the end.     

English,Israeli‐Arab and Saudi Arabian Adolescent Values

This paper compares the results of three surveys. The subjects comprise 96 adolescents in an English comprehensive school, 118 Arab adolescents in three schools in Israel and 89 adolescents in two schools in Saudi Arabia. The first and last groups of subjects have a modal age of 14 years whereas the majority of the second group are 15 years of age. The open‐ended questionnaire comprised 10 prompts designed to elicit responses concerning ideals and least ideals, most and least preferred companions, use of solitude, summum bonum, most and least desired outcomes to life and nascent philosophies. Two methods of analysis were used. First, references to dominant themes were totalled; secondly, responses were assigned to six categories according to the dominant values expressed from materialistic to altruistic. Similarities but also significant differences were found in the dominant themes and significant differences were also apparent in the values that were expressed. Most marked was the high value placed on parents and friendship by the English young people, the importance attached to education by the Israeli‐Arab group and the prominence given to Islam by the Saudi Arabian adolescents.     

Somatic embryogenesis in wild relatives of cotton （Gossypium Spp.）

Wild cotton species can contribute a valuable gene pool for agronomically desirable cultivated tetraploid cultivars. In order to exploit diploid cotton a regeneration system is required to achieve transformation based goals. The present studies aimed at optimizing the conditions for regeneration of local varieties as well as wild species of cotton. Different callus induction media were tested with varying concentrations of hormones in which sucrose was used as nutritional source. Different explants （hypocotyls, cotyledon, root） were used to check the regeneration of both local cotton plants and wild relatives using T ＆ G medium, BAP medium, CIM medium, EMMS medium, and cell suspension medium. Different stages of embryogenicity such as early torpedo stage, late torpedo stage, heart stage, globular stage and cotyledonary stage were observed in wild relatives of cotton. The results of this study pave the way for establishing future transformation methods.