Hypovitaminosis D: are medical students at risk?

Vitamin D deficiency is a pandemic problem mostly diagnosed in elderly. Few studies are available exclusively done on the topic among young adults. Specific professions such as medical students may have higher risk for developing hypovitaminosis D. We aimed to assess the vitamin D status in medical students of Iran University of Medical Sciences; and to define a cut-off point for 25-hydroxyvitamin-D [25[OH]D] level based on secondary hyperparathyroidism. This was a cross-sectional study on 100 medical students conducted during October 2012. Serum 25[OH]D, intact parathyroid hormone [iPTH], and calcium were measured. Age, sex, body mass index, daily dietary fish and egg consumption, sun exposure, and sunscreen usage were recorded. The association between serum 25[OH]D and iPTH was assessed. Receiver operating characteristics curve analysis was performed. 25-hydroxyvitamin-D level was <30 ng/ml in 99% of all participants, and <20 ng/ml in 77%. Mean serum 25[OH] D level was 16.8 +/- 4.7 ng/ml. iPTH level in the group with 25[OH]D level of <10 ng/ml was significantly higher than in those with serum 25[OH]D level of 10 to <20 ng/ml and 20 to <30 ng/ml [109 +/- 47 pg/ml, 47 +/- 27 pg/ml and 46 +/- 19 pg/ml, respectively; P = 0.0001]. There was a significant linear inverse correlation between serum iPTH and 25[OH]D [r= -0.36, P = 0.0001]. 25[OH] D level of 15.4 ng/ml was determined as the optimal cut-off point in detecting possible secondary hyperparathyroidism. To improve the community vitamin D status, in addition to population-based food fortification programs, educational programs seem essential; not only for general population, but also for the more educated groups

Cigarette smoking and spermatozoa I. histochemical differences between spermatozoa of cigarette smokers and non-smokers

Thirty semen specimens were taken from non-smokers and another thirty specimens from heavy smokers. Sperms of both groups were examined histochemically for some enzymes concerned with energy production [adenosine triphosphatase, lactate dehydrogenase and succinic dehydrogenase] and penetrating power [non-specific esterase and acrosin]. The histochemical reactions for these enzymes were lower in the sperms of the smokers than those of non-smokers revealing more aspects of the detrimental effects of cigarette smoking on spermatozoa

Ultrastructure of the gall bladder epithelium in guinea pig

The present study was performed to thorough the light on the fine structure of the gall bladder epithelium where there is no available literatures on this respect in guinea pig. This study was carried out on ten adult guinea pigs. They were sacrificed and the gall bladders were removed and were cut into different regons.The specimems were divided into small pieces for parafin sections and very small pieces immersed in glutaraldehyde for E/M. From the ultrastructural study, it can be concluded that: the lining epithelium is composed of ordinary epithelial [clear] cells, pencil [dark] and basal cells. The first two types of cells possess microvilli on their luminal surface. The apical ends of the lateral walls appear denser than the basal segments due to the presence of tight junctions. The lateral cell walls show infolded membranes. The basal plasma membrane is attached to the lamina propria by peg - and-socket interdigitations.The gall bladder epithelium of guinea pig is capable of actively secreting mucus droplets and do so as a merocrine secretion.The cytoplasm presents cuticular, subcuticular, supranuclear, nuclear and basal zones. Large dense and stippled granules are found in the subcuticular zone. Also, the cytoplasm contains mitochondria and endoplasmic reticulum, mainly in the subcuticular zone.The guinea pig has a well developed gall bladder, much similar to that of man