Ultrastructural changes of kidney in diabetic rats.

OBJECTIVES: To demonstrate histopathological changes in diabetic kidneys of the rat on ultrastructural level with focusing on glomerular cellular environment. METHODS: Male Wistar rats were administered streptozotocin and after 8 weeks, their kidneys were studied using qualitative transmission electron microscope analysis. RESULTS: In diabetic kidneys, the presence of irregularly thickened glomerular membrana basalis (GBM), often up to six times as compared to healthy kidney GBM, mainly around peripheral capillary loops, was striking. We also demonstrated lamination and split appearance of GBM, with presence of delicate fibrillar structure, which was absent within normal GBM. Accumulation of mesangial matrix was found only occasionally. CONCLUSION: Model may be useful to better understand the mechanisms that play role in the progression of DM-induced renal disease and to comprehend the morphological changes, which this process leaves within the tissue. The clear association between ultra-structure and functional markers may not be necessary (Fig. 4, Ref. 27).

Long-term liquid nutrition intake and development of obesity: differences between young and adult rats.

OBJECTIVE: Obesity is particularly associated with an increased consumption of palatable fat and sugar dense food and beverages. Therefore, we examined the effect of a normocaloric liquid diet (Fresubin) with increased carbohydrate content (constituting 55% of calories) on development of obesity in different developmental periods in male Wistar rats. METHODS: Fresubin was provided to 3 groups of rats: the first group received Fresubin immediately after weaning (21st day of age) to the end of experiment (150th day of age) for 5 months; the second group was fed with Fresubin from weaning to adulthood (90th day of age) for 3 months; and the third group received Fresubin only in adulthood (from 90th to 150th day of age) for 2 months. The control group was fed with standard pellet chow from weaning to the end of the experiment. Body weight, food and water intake were periodically measured. After terminating the experiment, the adiposity index was determined. RESULTS: Rats fed with liquid nutrition showed increased energy intake and body weight in comparison with the control rats. Interestingly, while obesity in the juvenile rats developed as late as of 13 weeks after the Fresubin intake, the adult rats fed with liquid nutrition had significantly elevated the body weight already 2 weeks after starting the treatment. Increased adiposity index was observed in both groups of rats fed with Fresubin during the whole study as well as the adulthood. CONCLUSIONS: Our data indicate that feeding of male Wistar rats with a high carbohydrate normocaloric diet results in a substantial development of obesity. Moreover, exposure of juvenile individuals to obesogenic environment leads, after a certain "latent period", to the development of obesity that may reflect low protein content of used liquid diet or higher resistance of juvenile organism to the obesogenic factors. Finally, based on the data obtained we suggest that Fresubin, with respect to its properties, may serve as a diet for the development of obesity which may exemplify an "obesity model" applicable in small laboratory animals.

Does incorporation of gene for green fluorescent protein in BP6 fibrosarcoma tumor cells depress their intraperitoneal growth in rats? (In honour of Nobel Prize laureates 2008--Osamu Shimomura, Martin Chalfie, Roger Y. Tsien).

This manuscript was in honour of Nobel Prize in chemistry "for the discovery and development of the green fluorescent protein, GFP" to Osamu Shimomura, Martin Chalfie, and Roger Y. Tsien, simultaneously a brief information about experience with GFP in experimental tumorigenesis used this study is also presented. The experimental data have showed that BP6 cells incorporated with GFP gene have had smaller ability to induce both experimental intraperitoneal and subcutaneous tumor process. It was anticipated that incorporation of GFP gene might change physiological properties of cytoskeleton and worsen adhesive characteristics of tumor cells. It was also supposed that aftertime GFP will enable to monitor proliferation of cells not only within experimental work, but also in human medicine. GFP could help (supposedly) as reporter of proliferation, but also can serve as "target" for guide of tumorigenesis inhibiting substances. These ideas which are consequences of our experiments we append as congratulation to Nobel Prize in chemistry of the 2008 (Fig. 2, Ref. 44). Full Text (Free, PDF) www.bmj.sk.

Meniscoids in the small articulations in extremities of man.

Synovial folds in the primordia of the small articulations of the human hand and foot are described. The folds are constant in the stages of development during which the articular cavities are formed and they very often persists in adults. They are structurally very similar to the meniscoids described by Kos and Wolf in intervertebral articulations.

Chick and quail specific pattern of endplates and fibre-types in the plantaris muscle.

Species-specific endplate distribution and fibre-type pattern were found in the plantaris muscle (PL) of the chick and quail. The PL is proposed as a model for studies of nerve-muscle interactions in chimeras.