Assessment of subclinical magnesium deficiency in pregnant women

Introduction. The question of the ratio of calcium and magnesium in the body in the scientific community is not discussed as often as the role of each of these elements. Experts pay even less attention to the ratio of minerals in the body of pregnant women.Aim. To analyze the content of magnesium and calcium in the blood of pregnant women at different gestation periods and evaluate the ratio of magnesium / calcium in order to establish the calculated coefficient.Materials and methods. 272 pregnant women (age 31.85 ± 5.0 years) at different gestation periods were included in the study. The subjects did not complain, typical for the clinic of magnesium and calcium deficiency. All surveyed gave written consent to the study. A biochemical blood test (determination of the concentration of total calcium, magnesium) was carried out in the laboratory of LLC DNKOM in Moscow. Blood sampling from the cubital vein was carried out according to the standard method in the morning on an empty stomach after 10–12 hours of fasting.Results and discussion. Concentration of  total calcium in  the serum was (M  ±  SD) 2.28  ±  0.11  mmol/l, total magnesium  – 0.78 ± 0.07 mmol/l, magnesium/calcium ratio – 0.34 ± 0.03. Mean concentrations of calcium and magnesium were significantly lower in women in the II and III trimesters compared with the I trimester (p < 0.001). A decrease in magnesium concentration below the optimal for pregnant women of 0.8 mmol / l was observed in 37.5% of women in the first trimester, in 77.3% and 84.1% in the II and III trimesters, respectively. Serum magnesium concentration less than 0.7 mmol / l, reflecting a profound magnesium deficiency, was detected in the first trimester in 3.6% of women, in the second trimester – in 11.3% of women, in the third trimester – in 15.9% of pregnancies. Hypocalcemia (total calcium concentration less than 2.15 mmol/l) was recorded in 0.9%, 11.3% and 22.3% of pregnant women in the I, II and III trimesters. When calculating the magnesium/calcium ratio, subclinical magnesium deficiency was detected in 96.7% of pregnant women throughout pregnancy. Conclusion. The data obtained indicate the need for pregravid examination and early correction of metabolic disorders.>< 0.001). A decrease in magnesium concentration below the optimal for pregnant women of 0.8 mmol / l was observed in 37.5% of women in the first trimester, in 77.3% and 84.1% in the II and III trimesters, respectively. Serum magnesium concentration less than 0.7 mmol / l, reflecting a profound magnesium deficiency, was detected in the first trimester in 3.6% of women, in the second trimester – in 11.3% of women, in the third trimester – in 15.9% of pregnancies. Hypocalcemia (total calcium concentration less than 2.15 mmol/l) was recorded in 0.9%, 11.3% and 22.3% of pregnant women in the I, II and III trimesters. When calculating the magnesium/calcium ratio, subclinical magnesium deficiency was detected in 96.7% of pregnant women throughout pregnancy.Conclusion. The data obtained indicate the need for pregravid examination and early correction of metabolic disorder

The Nature of Aqueous Solutions of a Cationic Calix[4]arene: A Comparative Study of Dye–Calixarene and Dye–Surfactant Interactions

Among different types of calixarenes, the water–soluble ones are of especial interestbecause of their possible applications in biochemical research. In order to elucidate the natureof aqueous solutions of a cationic amphiphilic calixarene, substituted tetrapropoxycalix[4]arene bearing hydrophilic choline groups at the upper rim, we studied vis–spectroscopically the influence of the above system on the acid–base behavior of threeindicator dyes, namely, 2,4-dinitrophenol, bromophenol blue, and N,N/-dioctadecylrhodamine,at constant ionic strength of 0.05 M, maintained with NaCl addition. Simultaneously,‘apparent’ ionization constants, Kaa , of the same dyes were determined in the presence ofcommon cationic surfactant micelles. Within the concentration range from 1.0×10–5 to 0.01 M,the aforementioned water–soluble calixarene displays effects similar to those of micelles ofcetyltrimethylammonium bromide (or chloride). The shifts of the absorption and emissionbands in the visible region, as well as the alterations of the Kaa values against the ‘aqueous’ones appeared to be very similar in aqueous solutions of both calix[4]arene and cationicsurfactant. A conclusion can be made about aggregation (or association), i.e., micelleformation of the cationic calix[4]arene under study

Colloidal Nature of Cationic Calix[6]arene Aqueous Solutions

The study of the aqueous solutions of the cationic hexameric calixarene 5,11,17,23,29,35-hexakis (<i>N</i>,<i>N</i>-dimethyl-<i>N</i>-hydroxyethylammoniummethylene)-37,38,39,40,41,42-hexametoxycalix­[6]­arene hexachloride demonstrates their colloidal nature. Within the concentration range from 1 × 10^–5 to 0.01 M, this compound forms positively charged aggregates of a much larger size as compared with those of tetrameric cationic calix[4]­arene previously studied by us. The aggregation was confirmed both by DLS and TEM experiments; the last method revealed that the 10² to 10³ nm sized particles consist of smaller primary aggregates. These aggregates manifest themselves in displaying alteration of absorption spectra and marked shifts of apparent ionization constants of common acid–base indicators. These shifts resemble those registered in micellar solutions of cationic surfactants and cationic polyelectrolyte brushes. The pCl measurements also confirm the formation of calixarene aggregates. The dye associations with the calixarene are governed rather by interactions with the aggregates of the macrocycles than by expected inclusion of the guest into the hosts cavity. Hence, on using ionic calixarenes in aqueous media, not only inclusion phenomena but also micellar effects should be taken into account