[Development of a learning game for ophthalmic technicians: "Orthoptist Simulator"]. / Développement d'un jeu sérieux pour la formation des orthoptistes : « orthoptist simulator ¼.

INTRODUCTION: E-learning is a pedagogic approach that relies on the use of electronic media and devices as tools to improve access to training, communication and interaction, facilitating the adoption of knowledge, skills and/or behaviors. Learning games offer a learning and training environment using entertaining elements from video games in a real-life scenario. The objective of this work is the conception of a learning game for training ophthalmic technician students. METHODS: Design of a learning game, in collaboration with iLumens and the Dowino® corporation, allowing the performance of an orthoptic evaluation in a child without ocular pathology. RESULTS: We developed the "Orthoptist Simulator" a learning game that faithfully reproduces an orthoptic box with necessary tools to carry out an orthoptic evaluation with ocular motility examination. The game offers learning, training and self-evaluation modes. It allows the student to evaluate a young patient, take a history and perform the 17 most frequently used orthoptic tests. The student thus creates a report of the results of these tests to be transmitted to the ophthalmologist who requested the workup. CONCLUSIONS: To our knowledge, we have set up the first learning game for the training of future ophthalmic technicians, which is an innovative educational tool and complementary to traditional training. This game could also be used to train ophthalmology residents in ocular motility examination. This new instrument will require future evaluation to determine its real impact on training.

World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guidelines for evaluating the efficacy of anthelmintics in swine.

As a follow-up to a previous guideline publication on efficacy evaluation of anthelmintics in ruminants, an expert group of the World Association for the Advancement of Veterinary Parasitology presents similar guidelines for the testing of anthelmintics in swine. The goal of the guidelines is to develop uniform testing standards and registration requirements. Data obtained from investigations according to the guidelines should be internationally accepted in the registering of drugs. Further, the use of the guidelines may contribute towards reducing costs, labor and the number of experimental animals used for drug testing.

The multiple forms and kinetic properties of the N-acetyl-beta-D-hexosaminidases from colonic tumours and mucosa of rats treated with 1,2-dimethylhydrazine.

The separation and purification of the N-acetyl-beta-D-hexosaminidase activities from tumours induced by 1,2-dimethylhydrazine in the rat colon and from colonic mucosa of tumour-bearing animals are reported. Mucosa contained N-acetylhexosaminidases A and B, as well as a third form whose properties with regard to electrophoretic mobility and thermostability lay between those of A and B. Tumours contained only N-acetylhexosaminidase A and B activities. Each form possessed both N-acetylglucosaminidase (EC 3.2.1.30) and N-acetylgalactosaminidase (EC 3.2.1.53) activities, which could not be separated by a variety of techniques. The alteration of the ratio of the two specific activities in each form during purification, together with differences in the kinetic inhibition constants and behaviour during inactivation by various reagents or a temperature of 50 degrees C, supported the belief that each form contains the two enzyme activities, glucosaminidase and galactosaminidase, at separate active sites. This model is in contrast with that reported for these activities from a number of other sources. A variety of treatments reported to cause the conversion of form A into a form resembling B failed to produce such an effect on the rat colonic hexosaminidases.

The multiple forms and kinetic differences of rat colonic beta-N-acetylhexosaminidases.

Rat colonic beta-N-acetylhexosaminidase (2-acetamido-2-deoxy-beta-D-glucoside acetamidodeoxyglucohydrolase, EC 3.2.1.30) has been separated into three forms by DEAE-cellulose chromatography with an increasing salt gradient. It was not possible to separate the glucosaminidase activity from the galactosaminidase activity by a variety of chromatographic procedues, but the ratio of the two specific activities varied during purification. The pH optima were however identical, for both activities and all three forms. Kinetic measurements including inhibition by substrate analogues showed differences between the two activities as well as among the three forms. A common active site model was inconsistent with the results. Data from mixed substrate experiments were consistent with a model wherein the two activities reside in seperate active sites, each able to be inhibited by the substrate for the other site. The effect of acetate and SH reagents confirmed the two-site model. Treatment with neuraminidase, thimerosal, p-hydroxymercuribenzoate, HgCl2 and AgNO3 or heating at 50 degrees C did not produce any effect on the A form that could be identified as a conversion to the B form. Measurement of the effects on both activities supported the two-site model. It is concluded that the relationship between the A and B forms in the rat colonic mucosa hexosaminidases must be different from that reported for such enzymes from other sources.

Pathophysiology of swine trichuriasis.

Infection of pigs by the whipworm (Trichuris suis) resulted in profuse diarrhea on postinfection days 17 to 21. Anorexia, retardation of growth, dehydration, and emaciation were observed in infected pigs. Scanning electron micrography showed nematodes embedded in the mucosa of the cecum and colon, with resultant disruption of the mucosa. Infected pigs had decreased values of albumin, amylase, calcium and creatine phosphokinase, but increased values of alpha-, beta-, and gamma- globulins, total iron-binding capacity, copper, potassium, uric acid, and aspartate aminotransferase.

Studies on the kinetics of glycosidases from chemically-induced rat colonic tumours and normal rat colon.

K-m values of beta-N-acetylglucosaminidase (2-acetamido-2-deoxy-beta-D-glucoside acetamidodeoxyglucohydrolase EC 3.2.1.30), beta-N-acetylgalactosaminidase (EC 3.2.1.53), beta-galactosidase (beta-D-galactoside galactohydrolase EC 3.2.1.23) and alpha-L-fucosidase (alpha-L-fucoside fucohydrolase EC 3.2.1.51) of distal colonic tumours, induced in rats by 1,2-dimethylhydrazine, were found to be significantly different compared with the values for the enzymes of the colonic mucosa of the control and tumour-bearing animals and of the proximal colonic tumours. The inhibition kinetics data also showed a significant difference between the enzymes of the distal colon tumours and of other experimental tissues. The data on the effect of pH on enzyme kinetics (pK values) showed no significant difference in the catalytic groups of the active centres of enzymes from tumours and from the control colonic mucosa. Tumour beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase compared with the enzymes from other experimental tissues were found to be different in their thermal inactivation kinetics. K-m values of 14 days old foetal intestinal beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase were significantly different from the values obtained for the adult mucosal enzymes but were similar to those of the distal colonic tumour enzymes.