Menstrual function and mental health of medical students during the COVID-19 pandemic: a continuous cross-sectional study

Aim. To assess the impact of new coronavirus infection (NCI) and COVID-19 vaccination on menstrual function in comparison with the frequency of depressive disorders during the COVID-19 pandemic among female students of a medical university. Materials and methods. Data for a continuous transverse (cross-sectional) study were obtained using an online survey. The questions included demographics, characteristics of menstrual function, the history of COVID-19 and vaccinations against it, and the standard CES-D (Center for Epidemiologic Studies Depression Scale) questionnaire. The survey included 1.879 female medical students. The exclusion criteria were age under 18 and over 25 years, hormonal contraceptives, pregnancy, childbirth during the last year, and vaccination after COVID-19. After applying the exclusion criteria, three study groups were formed. Group 1 included female students with a history of NCI (n=140), group 2 included students with no history of NCI, who were initially vaccinated against COVID-19 (n=647), group 3 (control group) included unvaccinated students with no history of NCI (n=55). Results. There were no differences in the prevalence of changes in menstrual function in female students after the NCI (49.3%) and after COVID-19 vaccination (39.6%) compared to the control group (43.6%); p=0.477. The rate of depression in the overall study cohort was 43.3%, without any significant differences between the study groups. Significant predictors of changes in menstrual function during the pandemic were marriage (odds ratio OR 2.33 [1.513.61]), depression (OR 1.72 [1.282.3]), a history of menstrual dysfunction (OR 1.5 [0.121.99]), and later menarche (OR 1.76 [1.023.04]). Multivariate analysis did not show the significance of the history of NCI and vaccination as factors of menstrual dysfunction (OR 1.61 [0.892.90] and OR 0.91 [0.591.41], respectively). Conclusion. During the COVID-19 pandemic, female medical students reported frequent changes in menstrual function and depressive disorders. During the pandemic, the most significant predictors of menstrual disorders in female students were depression, a history of menstrual dysfunction, and marriage. A multicenter prospective study is necessary to clarify the mechanisms of the pandemic's impact on menstrual function

Supramolecular Assembly of Organophosphonate Diesters Using Paddle-Wheel Complexes: First Examples in Porphyrin Series

The reactions of dicopper tetrapivalate complex Cu₂(μ-OOC-<i>t-</i>Bu)₄­(NCMe)₂ (<b>1</b>) with triphenylphosphine oxide and diethyl phosphite allow paddle-wheel (PW) copper­(II) complexes with phosphorus-containing axial ligands (<b>2</b>, <b>3</b>) to be obtained. When <i>meso</i>-bis­(diethoxyphosphoryl)­porphyrins <b>4M</b> were employed in this ligand exchange reaction, a series of one-dimensional (1D) homo- and heterometallic coordination polymers <b>5M</b> composed of PW subunits and organophosphonate diesters were prepared and characterized by means of single crystal X-ray analysis. Planar porphyrinate <b>4Pd</b> and nonplanar metalloporphyrinates <b>4Cu</b> and <b>4Ni</b> proved to be appropriate molecular structural blocks for assembly of coordination polymers. The structural parameters of the tetrapyrrolic macrocycles incorporated into the polymer chain are determined by the nature of the metal center of the porphyrin moiety. While the geometry of palladium­(II) and nickel­(II) porphyrinates <b>4Pd</b> and <b>4Ni</b> does not change significantly in the polymer chain, saddle-shaped Cu­(II) porphyrinate <b>4Cu</b> exhibits a nearly planar core configuration, being coordinated to the copper centers of PW fragments by two peripheral phosphoryl groups in the polymer chain. The geometry of the tetrapyrrolic core is a key parameter influencing the structural properties of the polymeric materials. For <b>5Pd</b> and for isostructural <b>5Cu</b>, all metal centers of the polymeric chain are aligned. The planar macrocycles of adjacent chains are parallel and are shifted one to another in such a way that the angle between the Pd···P and Pd···Pd directions is 40.4°, and the distance between the nearest palladium­(II) atoms of neighboring chains is 11.668 Å. There is no free volume in these crystals. In the crystals of <b>5Ni</b>, formed by nonplanar porphyrinates, only copper atoms of the PW pivalate moiety are located in one plane, and zigzag chains are formed so that two adjacent tetrapyrrolic macrocycles are located in alternating positions with respect to this plane, the nickel atoms being displaced from this plane by 1.548 Å. This arrangement naturally leads to the formation of regular pores. The resulting channels have an effective cross-section of about 10 × 12 Å and represent ca. 18% of the volume of the crystal. The exchange reaction between the free-base porphyrin <b>4H</b>_<b>2</b> and an excess of copper­(II) pivalate complex <b>1</b> is accompanied by the metalation of the porphyrin core affording the polymer <b>5Cu</b>. Moreover, self-assembly of metalloporphyrinate <b>4Zn</b> is observed under studied experimental conditions, which interferes with the formation of the target mixed coordination polymers

Diversity and Metabolism of Microbial Communities in a Hypersaline Lake along a Geochemical Gradient

In the south of western Siberia (Russia), there are many unique and unexplored soda, saline, and freshwater lakes. In this study, the results are presented on microbial diversity, its metabolic potential, and their relation with a set of geochemical parameters for a hypersaline lake ecosystem in the Novosibirsk region (Oblast). The metagenomic approach used in this work allowed us to determine the composition and structure of a floating microbial community, the upper layer of silt, and the strata of bottom sediments in a natural saline lake via two bioinformatic approaches, whose results are in good agreement with each other. In the floating microbial community and in the upper layers of the bottom sediment, bacteria of the Proteobacteria (Gammaproteobacteria), Cyanobacteria, and Bacteroidetes phyla were found to predominate. The lower layers were dominated by Proteobacteria (mainly Deltaproteobacteria), Gemmatimonadetes, Firmicutes, and Archaea. Metabolic pathways were reconstructed to investigate the metabolic potential of the microbial communities and other hypothetical roles of the microbial communities in the biogeochemical cycle. Relations between different taxa of microorganisms were identified, as was their potential role in biogeochemical transformations of C, N, and S in a comparative structural analysis that included various ecological niches