Patterns of cigarette, hookah and other tobacco product consumption habits among undergraduate students of the University of Sarajevo before the COVID-19 outbreak in Bosnia and Hercegovina, a cross-sectional study.

Background: Tobacco products represent a major health risk factor and a potent way to help transmission of COVID-19. Current data regarding consumption of these products in the region are scarce. The aim of this study was to evaluate patterns of cigarette, hookah and other tobacco products consumption among undergraduate students from the University of Sarajevo before the COVID-19 outbreak in the country. Methods: This cross-sectional study based on a National Youth Tobacco Survey (NYTS) was conducted among undergraduate students from the University of Sarajevo in Bosnia and Hercegovina via an online questionnaire from 22nd to 26th of January 2020. Results: Out of 605 students involved in the study, most of them were female (N=429, 70.9%); 363 (60.0%) were enrolled in medical sciences; 159 (26.3%) were attending the 3rd year of their curriculum; 224 (37%) were original from Canton Sarajevo and 514 (84.9%) were living in urban environment. Two hundred thirty five students out of 605 (38.8%) were current smokers and 117 (19.3%) hookah smokers. Being female (OR=0.539, 95% CI 0.368-0.790, p=0.002), in the 1st or 2nd year of study (OR=0.805, 95% CI 0.667-0.972, p=0.024) and living in a rural environment (OR=0.335, 95% CI 0.191-0.585, p<0.001) were associated with reduced risk of cigarette consumption, while older age (22+ years) (OR=1.287, 95% CI 1.122-1.476, p<0.001) increased the same risk. On the other side, being female (OR=0.595, 95% CI 0.380-0.930, p=0.023), of younger age (18-21 years) (OR=0.832, 95% CI 0.743-0.932, p=0.001) and medical science student (OR=0.567, 95% CI 0.328-0.978, p=0.041) were associated with decreased risk of consuming hookah. Conclusions: This study provides an insight in prevalence of smoking among students at the University of Sarajevo. More antismoking efforts are needed, especially in urban environments; and a follow-up study, to be planned in the near future, should determine whether COVID-19 pandemic (and all the modifications of lifestyles connected with it) have eventually changed tobacco consumption patterns among undergraduate students.

Ultrastructure of plasma cells in harderian gland of laying hens.

Ultrastructure of plasma cells in Harderian gland was investigated using the transmission electron microscopy. For this research, we examined the glands of 32 laying hens collected at 1, 7, 20 and 40 days and 4, 6, 8 and 12 months of the birds' ages. The research showed that the stroma of the gland contains a large number of lymphocytes and plasma cells. Most of the plasma cells are mature, but morphologically do not show productive activity. Only some individual plasma cells, situated under the secretory epithelium of primary and secondary ducts, have extremely dilated cisternae of rough endoplasmic reticulum which contain moderately dense, granular material. The morphology of these cells indicates that they are in active stage of immunoglobulin production. Also, we identified plasma cells with two types of Russell bodies. One type of these bodies was small, round or oval, while the other had irregular, angular shape. It was noted that one plasma cell never contains both type of Russell bodies at the same time. These cells were often affected by apoptosis. Among them, in deeper part of the stroma, were situated the small plasmablast cells.