Effect of the developmental stage and thawing temperature on the survival and development of the vitrified embryos

The best developmental stage and the best thawing protocol suitable for cryopreservation of the early embryos are not well documented. The present study aimed at evaluating the effect of the ultra rapid cryopreservation [vitrification] technique, followed by slow or fast thawing protocol, on the fertilized ova, 4-cell embryos and morula. The vitrification method included equilibrating the ova in the vitrification solution [EFS40; consisted of 40% ethylene glycol, 30% Ficoll, 0.5 M sucrose in D-PBS] for 2 minutes before immersion in liquid nitrogen. Slow and fast thawing were done and the cryoprotectants were withdrawn by a hyperosmolar sucrose solution, which was then gradually diluted and replaced by culture medium. The best results were obtained with vitrification of the 4-cell embryos both with slow and fast thawing, which gave survival rate of 86% and 94%, and in vitro development rate of 74% and 80%, respectively. Fast thawing showed better survival rates [80%, 94%, 77%] and better in vitro development rates [60%, 80%, 63%] than those of slow thawing, following vitrification of the fertilized ova, 4-cell embryos and morula, respectively. These criteria of vitrification/ thawing could be inferred to the human 4-cell embryos in the IVF protocol

Developing an integrated organ/system curriculum with community-orientation for a new medical college in Jazan, Saudi Arabia

Jazan province m located in the south-west of the Kingdom of Saudi Arabia, The province is offlicted with a wide spectrum of diseases and therefore have a special need for more health services. The Faculty of Medicine at Jazan has been following the traditional curriculum since its inception in 2001 The traditional curriculum has been criticized because of the students inability to relate what they learned in the basic sciences to medicine, thus stifling their motivation. It was felt that much of what was presented in preclinical courses was irrelevant to what the doctor really needed to know for his practice. The College therefore, decided to change to an integrated curriculum. The study wm conducted in 2004-2005 in the Faculty of Medicine, Jazan University It began with a literature survey/search for relevant information and a series of meetings with experts from various institutions. A Curriculum Committee was formed and a set of guiding principles was prepared to help develop the new curriculum. A standard curriculum writing format was adopted for each module, If was decided that an independent evaluation of the new curriculum was to be done by experts -in medical education before submission for official approval There were several difficulties in the course of designing the curriculum, such as: provision of vertical integration, the lack of preparedness of faculty to teach an integrated curriculum, and .difficulties inherent in setting a truly integrated examination, Curriculum: The program designed is for 6 years and In 3 phases: pre-med [year I], organ/system [years 2 and 3], and clinical clerkship [years 4, 5, and 6], This is to be fallowed by a year of Internship. The pre-med phase aims at improving the students' English language and prepare them for the succeeding phases. The organ/ system phase includes the integrated systems and the introductory modules. The curricidum includes elective modules, early clinical training, behavioral sciences, medical ethics, biostatistics, computer practice, and research methods. The curriculum provides active methods of instruction that include: small group discussion tutorials, problem-based learning [PBL], case-study/ clinical presentations, seminars, skills practice [clinical skill lab], practical demonstration, and .student independent [earning. Methods of evaluating students include continuous and summative assessment. The new curriculum adopted by the Jazan Faculty of Medicine Is an integrated, organ/ system based, community-oriented, with early clinical skills, elective modules, and innovative methods of instructions

Structural study on cultured isolated fetal rat pancreatic islets

To perform a morphometric and structural study of the cultured isolated fetal rat pancreatic islets. Islets of the fetal rat pancreas, aged 22 days were isolated by the standard procedure of collagenase digestion and culture technique. The islets were cultured for 1, 2, 3, 4 and 5 days. The islets were counted under a dissecting microscope and islet diameter and purity were measured under a phase contrast microscope fitted with a calibrated grid. The islet specimens were fixed in buffered neutral formalin, dehydrated in alcohol and embedded in parablast. Sections were stained with hematoxylin and eosin. This study was conducted in King Fahd Medical Research Center, Faculty of Medicine, King Abdul-Aziz University, Kingdom of Saudi Arabia, during 2003 and 2004. The purity of the cultured islets gradually increased with time and was significantly different between the cultured groups. The number of the cultured islets gradually decreased with time. The islet diameter gradually increased with culture period. The islet purity and diameter were significantly different between the cultured groups. Parablast sections stained with hematoxylin and eosin showed that the shape and histological structure of the cultured islets were intact. The results of the present work represent an extensive morphometric structural study of isolated cultured fetal islets. The culture islet diameter and purity showed gradual increase with culture period, while the islet number showed gradual decrease

Early ultrastructural changes in the pancreatic islets transplanted into the tongue of diabetic rats

Isolated pancreatic islets transplanted into the tongue of streptozotocin diabetic rats were used for studying early ultrastructural changes, 24 and 72 h post-transplantation. Adult inbred Lewis rats were used both as donors and recipients, the latter were rendered diabetic by a single dose [40 mg/kg] of streptozotocin. The islets were isolated by the collagenase digestion technique. Isolated islets [2500-3000] harvested from 8 rats were injected into the tongue of each recipient rat close to the sulcus terminalis [a total of 6 transplantation was done]. Small pieces [lmm[3]] of the tongue were removed after 24 and 72 h from the site of injection and processed for electron microscopic examination. Our observations 24 and 72 h post-transplantation showed active secretory endocrine cells, most of which belonged to the B cell type as characterised by the morphology of their secretory granules. Some non-B cell entities could also be discerned from the pleomorphism of their secretory granules. Most of these cells showed proliferating Golgi zones along with normal looking rough endoplasmic reticulum ribosomes and mitochondria. Some cells showed degranulation 72 h after transplantation. Functional evaluation showed slight improvement in the diabetic state of the recipient rats