Introduction. Inadequate vitamin D supply worldwide is a public health problem. Low vitamin D levels during pregnancy can lead to abnormal placentation, placental insufficiency and abnormal fetal development, which contributes to poor health after birth.Objective of the study is to analyze the vitamin D status of premature infants born in the south of Russia.Materials and methods. A total of 141 premature infants were examined. Extremely low birth weight was found in 19 (13.4%) newborns, very low birth weight in 35 (24.8%), and low birth weight in 75 (53.2%).Results and discussion. Premature infants had vitamin D deficiency in the majority of cases (51%), with a median of 16.9 [11.7; 22.9] ng/mL. Correlation analysis demonstrated a positive association between 25(OH)D levels and body weight in very low birth weight infants (r = 0.34, p = 0.043). Serum vitamin D concentrations were 1.6 times lower in infants whose mothers did not receive multivitamins than in those whose mothers received multivitamins, 13.8 [9.7; 20.9] and 21.6 [16.9; 28.6] ng/mL, respectively (p = 0.001). Infants with an Apgar score of 7-10 had higher vitamin D levels, 17.8 [11.9; 22.7] ng/mL, than infants with severe asphyxia, 13.8 [9.9; 16.8] ng/mL (p = 0.036). Premature infants with congenital infection had lower 25(OH)D levels than infants without an infectious process, 15.6 [10.8; 22.9] and 18.4 [14.2; 22.7] ng/mL, respectively. Children with an infectious process that subsequently ended in death had lower 25(OH)D levels than children without an infectious process (p = 0.001). Children with cerebral ischemia had lower 25(OH)D concentrations than children without cerebral ischemia (p = 0.001).Conclusions. Premature infants born in the south of Russia have vitamin D deficiency in more than half of the cases. Administration of preparations containing cholecalciferol reduces the proportion of newborns with severe vitamin D deficiency, but does not ensure optimal serum levels. Initially low levels of 25(OH)D can be considered as an unfavorable prognostic sign against the background of the development of congenital infection.
This paper is describing an investigation of surfactants influence on zinc sulfide wetting by non-polar liquids and sphalerite concentrates pressure leaching parameters. Zinc sulfide preferential wettability by oil was tested in presence anionic surfactants with different chemical structures. Interfacial tension was determinated by the maximum liquid drop volume method. It allows to determine surfactant potential effectivity on pressure leaching of sphalerite concentrate. It is found that SDBS decreases zinc sulfide wettability by non-polar liquids in a greater degree than SDS and Ls. Combined addition of Ls and SDBS allowed to receive residues with optimal coarseness, eliminate pellet formation and increase zinc extraction.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.