High dose vitamin D supplementation decreases the risk of deficiency in male conscripts, but has no effect on physical performance-A randomized study.

Purpose: Physical load during military training might increase the need for vitamin D; therefore, supplementation could be beneficial for 25(OH)D serum levels and physical performance. Methods: One hundred and twelve male conscripts were randomized into two vitamin D oil capsule supplementation groups: 55 participants in the 600 IU group and 57 in the 4000 IU group with a follow-up period from July 2021 to May 2022. Physical fitness tests were performed in July, October and May. Hand grip strength tests were performed in July, October and January. Blood serum (25(OH)D), parathyroid hormone PTH), calcium and ionized calcium (i-Ca) values were measured in July, October, January and May. Results: The 600 IU group had a lower (p < 0.001) value of 25(OH)D at all time points compared to the 4000 IU group, except at baseline. None of the subjects in the 600 IU group reached sufficient levels of 75 nmol/L of 25(OH)D in January and May. In May, 60% of participants in the 600 IU group and 30% in the 4000 IU group had 25(OH)D levels under 50 nmol/L. No significant differences in PTH or i-Ca values were found between the study groups at any time point. No significant differences at any time point were found in the physical fitness test or hand grip strength test between the groups. Conclusion: A 10-month vitamin D supplementation with 4000 IU decreased the incidence of vitamin D deficiency (<75 nmol/L) in young, male army conscripts during wintertime, but no differences in physical performance were found compared to 600 IU supplementation. Level of Evidence: Level I, Prospective randomized study.

Morphological study of incompetent saphenous veins: apoptosis and ultrastructural changes of smooth muscle cells.

BACKGROUND: Varicose veins affect approximately 25% of people in industrialized countries. METHODS: The study aimed at detecting apoptotic cells and histopathological changes in varicose vein walls. Patients (N.=41) with varicose veins and 30 control group patients were divided into two groups according to their age (younger and older than 50 years). Apoptosis was determined by the TUNEL assay, elastin and collagen IV expression by immunohistochemistry and ultrastructural changes by transmission electron microscopy. RESULTS: The results show that the number of apoptotic cells in the layers of varicose veins increased, in particular in a group of patients aged over 50 years. In the varicose veins as compared to control veins the elastic fibers were found to be thinner, more fragmented and disorderly arranged. Elastin and collagen IV expression was found to decline in the intima and the media of varicose veins in both age groups. Electron microscopy demonstrated hypertrophy and degeneration of smooth muscle cells. Furthermore, cells with ultrastructural feature of apoptosis were noted. In the disorganized and expanded extracellular matrix membrane-bound vesicles, ghost bodies with different size and electron density were observed. Ghost bodies seem to bud off from smooth muscle cells and are likely to be involved in extracellular matrix remodeling as they are seen in close contact with collagen fibers. CONCLUSIONS: The study demonstrates increase of apoptotic cells in the wall of varicose veins along with vein wall structural abnormalities including alterations of smooth muscle cells and decline of elastin and collagen IV expression.