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The aim of the work was to evaluate the in vivo biological behaviour of polymeric membrane materials for glaucoma implants. The base material was biostable synthetic terpolymer (PTFE–PVDF–PP) with proved biocompability (PN-EN ISO 10993). The samples manufactured in the form a membrane were subjected to chemical and physical treatment to create an open pore system within the polymer matrix. As a porogenic phase biodegradable natrium alginate in a fibrous form was employed. The non-perforating deep sclerectomy technique was performed in a rabbit model. The clinical observations were made after 14 and 30 days. During the study clinical symptoms of a moderate degree were observed, and histopathological changes were typical for foreign body implantation. At the end stage of the study no significant difference in histopathological assessment was found between control and experimental group. Similarities observed in both groups and relatively mild histopathological changes in the tissue surrounding the implant indicate that the observed symptoms come from a deep scleral trauma caused by surgery, and not by the presence of the implant itself.

S y n t h e s i s o f 3 , 4 -D i h y d r o -2 H -p y r i d o [ 1 , 2 -a ] [ 1 , 3 , 5 ] t r i a z i n -2 -o n e sAbstract: A convenient method leading to fused pyrido[1,2-a] [1,3,5]triazine-2-ones is described. It consists in a one-pot, two-step reaction of N-(2¢-pyridinyl)benzoylacetamide with nitrosobenzenes. On the other hand, N-(2¢-pyridinyl)acetoacetamide provides a C-2 condensation/addition product with nitrosobenzene. N-(2¢-Pyridinyl)benzoylthioacetamide and N-(2¢-pyridinyl)acetothioacetamide with nitrosobenzene undergo oxidative heterocyclisation leading to [1,2,4]thiadiazolo[2,3-a]pyridine derivatives.The interest in the pyrido[1,2-a][1,3,5]triazine system arises from its wide biological activity, 1,2 which comes from its antagonistic effect upon 5-HT 2 and 5-HT 2a serotonin receptors. Such influence can result in: mediating coronary blood flow, 1a decreasing mean arterial blood pressure, 1b and the anti-thrombotic effect 1c in mammals. Other disorders, for whose prophylactic or therapeutic treatment pyrido[1,2-a][1,3,5]triazine derivatives can be used, are those involving airway constriction in human or animals: asthma, emphysema, chronic bronchitis, chronic obstructive pulmonary disease, 2 and various psychotic conditions including schizophrenia, depression, anorectic or bulimic eating disorders, and anxiety in humans. 2c Since 1952, when a possible approach to this system was mentioned for the first time, 3a several general methods of synthesis of pyrido[1,2-a][1,3,5]triazines have been invented, mostly leading to their oxo derivatives.Cyclodimerisation of iso(thio)cyanates leads to pyrido[1,2-a][1,3,5]triazine-2,4-di(thi)ones. 3b-d The other methods include: reaction of isocyanates 4a or active esters of imidodicarbonic 4b or carbonic 4c acid with 2-aminopyridine or other amidines and cyclisation of (thio)urea derivatives 3a or their reaction with isothiocyanate. 4d Pyrido[1,2-a][1,3,5]triazine-4-ones can be obtained from urea derivatives, 5a,b e.g. by their cyclisation, 5a or reaction of aryl isocyanates and unsymmetrical carbodiimides containing 2¢-pyridine ring. 5c,d There are only a few examples of the syntheses of pyrido[1,2-a][1,3,5]triazine-2-(thi)ones known. 3d,6