A new look at acid catalyzed deacetylation of carbohydrates : A regioselective synthesis and reactivity of 2-O-acetyl aryl glycopyranosides

Abstract In the present work we report that acetyl groups of per – acetylated aryl glycosides have different reactivity during the acidic deacetylation using HCl/EtOH in CHCl3, which leads to preferential deacetylation at O-3, O-4 and O-6. Thereby, the one-step preparation of 2-O-acetyl aryl glycosides with simple aglycon was accomplished for the first time. It was proved that the found reagent is to be general and unique for the preparation of series of 2-О-acetyl aryl glycosides. We have determined the influence of both carbohydrate moiety and the aglycon on the selectivity of deacetylation reaction by kinetic experiments. Using DFT/B3LYP/6-31G(d,p) and semi-empirical АМ1 methods we have found that the highest activation barrier is for 2-О-acetyl group. This completely explains the least reactivity of 2-О-acetyl group.Peer reviewe

Electrochemical creatinine determination with metal-organic framework catalyst based on copper and acetylenedicarboxylic acid

Fast and accurate determination of creatinine is critical in kidney function diagnostics. This paper discusses the usage of the metal-organic framework based on copper(II) and acetylenedicarboxylic acid (CuADCA) as a catalyst of electrochemical oxidation of creatinine, glucose and urea. CuADCA was synthesized by deprotonation with triethylamine for the first time. Successful synthesis was confirmed by FTIR and EDS. The material was characterized by SEM, EIS, and CV. CuADCA forms laminated-like flakes with diameter from 1 µm to 20 µm, which is consistent with the polymer-like structure. CV and EIS analyses showed that CuADCA immobilized on GCE acts as a catalyst in electrooxidation reaction of glucose, urea, and creatinine. The sensitivity of creatinine detection, 1057±99 µA/mM, was higher than the detection sensitivity of glucose and urea by more than 100 times with the limit of detection of 2 µM, so CuADCA is a promising material for further development of enzymeless sensors for creatinine

The significance of circulating progenitor cells with osteogenic activity in the of atherosclerosis development in patients with type 2 diabetes mellitus

BACKGROUND: There is an interaction between cell-mediated pathway of the vessel calcification and atherosclerosis processes. In some studies the relation beeen circulating osteogenic progenitor cells and cardiovascular diseases was shown. Though its role in the development of cerebrovascular diseases (CVD) in Type 2 diabetes mellitus (T2DM) remains unknown. AIM: To study the level of circulating endothelial (CD34 + VEGFR2 +) and osteogenic (CD34 + OCN +) progenitor cells in patients with CVD and T2DM. METHODS: We observed patients with CVD (coronary artery disease and / or chronic limb threatening ischemia) with T2DM and without T2DM. Patients with CVD and T2DM were included in group 1 patients with CVD and without T2D were included in group 2. The level of CD34 + VEGFR2 cells and CD34 + OCN+ cells was determined by flow cytometry.There were no differences in the age, gender, lipid profile, body mass index, creatinine clearance, myocardial revascularization and lower limb revascularization between the 2 groups.The level of CD34 + VEGFR2 cells and CD34 + OCN+ cells was determined by flow cytometry. The number of cells was determined by a percentage of the number of CD34+ cells. RESULTS: We observed 71 patients (38 women, mean age 67 years [62, 74]). Forty six patients were included in group 1 (28 women, mean age 68 years [63;75], 25 patients (10 women, 66 years [55;72]) were included in group 2. We found that in patients with CVD and T2DM demonstrated higher amounts of CD34+OCN+ cells than CD34+VEGFR2+ cells. (29.7% [26.2;36.1] and 11.8% [9.57;17.2], p<0.001). In the 1st group observed higher amounts of CD34+OCN+ cells, than in the 2d group (29.7 [26.2;36.1] и 25.6 [17.3;30.7] соответственно; p=0.035). Positive correlation was established between amount of CD34+OCN+ cells and atherogenic lipid fraction, LDL (r=0.4; р=0.032) and total cholesterol (r=0.27; р=0.05) in patients of group 1.While SYNTAX score tertiles and amount of CD34+OCN+ cells (r = 0.50, p=0.021) were the positive correlation. Between coronary artery calcium score and amount of CD34+OCN+ cells (r = 0.49, p=0.034) was the positive correlation. CONCLUSIONS: Acquired results may indicate the active role of CD34+OCN+ endothelial progenitor cells in atherosclerosis and vascular calcification in patients with T2DM

Bioaccumulation of trace elements in vegetables grown in various anthropogenic conditions

Hazardous compounds accumulate in plants and animals as a result of anthropogenic impact. Trace elements, such as heavy metals, move up in the system of snow – soil – water – plant – animal. When contaminants accumulate in plants that serve as animal feed, they eventually accumulate in the animals that consume the feed because heavy metals usually enter living organisms via digestive tract, i.e., with food. In 2003–2021, we studied fodder plants grown and harvested by urban zoological organizations, e.g., zoos, nature corners, etc. This research covered the Central Federal District represented by the cities of Moscow, Ivanovo, Yaroslavl, and Uglich. The empirical part of the study relied on a combination of modern ecological, biochemical, and statistical methods. A KVANT-2AT atomic absorption spectrometer was used to define the trace elements and their quantities. Broccoli proved to be the most resistant feed vegetable to all the toxic elements in this study. Kohlrabi, sweet potato, and dill had low content of lead and cadmium, while garlic was highly resistant to cadmium and arsenic. Spinach, fennel, potatoes, beets, and bell peppers, which were used as fodder in metropolis conditions, exceeded the maximal permissible concentration of heavy metals. The samples obtained from the Moscow Zoo contained by 1.98 times more zinc, by 1.06 times more copper, and by 89.47 times more lead than average. The samples from Ivanovo accumulated the greatest extent of iron, which exceeded the average level by 3.26 times. The vegetables from Uglich and Ivanovo had the lowest concentration of zinc, which was by 67.86 and 62.70% below the average, respectively. The samples from Yaroslavl contained by 33.08% less copper. In 2003–2021, feed vegetables grown in the Central Federal District had an average increase in zinc, copper, and lead by 1.13, 1.45, and 2.80 times, respectively. The level of iron stayed almost the same throughout 2018–2021, while that of arsenic gradually decreased in concentration. The accumulation level of zinc, copper, iron, and arsenic in feed vegetables appeared to depend on the concentration of their water-soluble metal forms in the soil. Therefore, forage agriculture in urban areas requires constant chemical and toxicological tests to prevent contaminated feed from entering animal diet

Trace Elements in Indian Peafowl (Pavo cristatus): Exposure Routes

Urbanization leads to chemical pollution. Contaminants accumulate in feed and enter animal body through digestive tract. Numerous studies have established that the level of mineral content in the environment reflects the technogenic load on the territory and is transmitted in the system through products of plant and animal origin, which can be used to prevent and correct elementoses. This research featured feathers of Indian peafowls Pavo cristatus (n = 33), diet components (n = 303), their drinking water (n = 94), soil (n = 123), and snow (n = 204). The micro-elemental profile was defined using an atomic absorption spectrometer. The samples were obtained from zoological institutions of Mosco w, Ivanovo, and Yaroslavl. As for the feathers, the average Zn accumulation level was 122.74 ± 9.64 mg/kg, Cu – 5.36 ± 0.05 mg/kg, Fe – 508.06 ± 56.84 mg/kg, Pb – 6.75 ± 1.13 mg/kg, Cd – 1.65 ± 0.26 mg/kg, and As – 0.61 ± 0.23 mg/kg. The variability of the concentration of microelements in the sample was as follows, %: Zn – 73.9, Cu – 94.3, Fe – 111.6, Pb – 150.0, Cd – 136.88, and As – 203.87. The average levels of accumulation of elements in the biological media decreased in the following order: Fe > Zn > Cu > Pb > Cd > As. The share of Zn in the total of all determined elements was 0.7–48.0%, Cu – 0.04–2.8%, Fe – 46.2–92.8%, Pb – 0–2.5%, Cd – 0–2.5%, and As – 0–4.6%. The diet analyses showed the following results for Moscow, Ivanovo, and Yaroslavl, respectively: Zn – 11.35, 6.60, and 2.50 mg; Cu – 2.29, 0.75, and 0.41 mg; Fe – 55.83, 30.54, and 6.78 mg; Pb – 0.14, 0.18, and 0.01 mg; Cd – 0.02, 0.01, and 0.005 mg; As – 0.04, 0.02, and 0.002 mg. If the birds consumed all the food they received, the approximate total daily intake of the selected essential microelements Zn was 16.7–75.7% of the recommended daily intake, Cu – 13.7–76.3%, and Fe – 48.4–398.79%. Pb, Cd and As stayed within the daily norm. The oral route of intake was registered for Zn, Cu, and Fe in Yaroslavl and for Cd in all samples. Inhalation was registered as the main route of intake for Fe in Moscow and Ivanovo, as well as for As and Pb in Moscow. The highest intake of Pb was registered in Ivanovo and Yaroslavl. The analysis revealed the multi-route and multi-environment exposure of urban birds to microelements, including heavy metals. The level of concentration of essential microelements in the biological media depended on the diet. Fe in Moscow and Ivanovo and As in all the samples came from the soil cover, which had a high content of these elements. The gross content of Pb in the soil samples from Moscow and the drinking water from Yaroslavl and Ivanovo demonstrated the greatest impact on the avian organism. The snow samples had the least effect on the el emental status of the bioenvironments

Infusion Effect on Postoperative Intestinal Failure

Purpose: improvement of the results of operative treatment in patients with emergency abdominal pathology by selecting the tactics of perioperative infusion therapy that would be optimum for postoperative bowel function recovery.Materials and methods. 52 surgical patients (28 men, 24 women, mean age 57.5±14 years) subjected to various emergency abdominal surgeries were studied. The patients were split into 2 groups. It was a prospective study; group affiliation was determined by randomization. In group 1 (n=29), balanced ionic solutions were used for perioperative infusion therapy. In group 2 (n=23), balanced ionic solutions were combined with synthetic colloids. The infusion therapy volume during operation was 2359 ml on average. To determine the bowel function during the postoperative period, comprehensive dynamic assessment of the gastrointestinal tract (GIT) status was undertaken, which included physical examination, intra-abdominal pressure (IAP) measurement, and ultrasound visualization of the intestinal wall condition; the dynamics of intestinal absorptive function and common laboratory tests were monitored. The level of intestinal failure during the postoperative period was determined based on assessment of the GIT condition and recommendations of the National Guidelines for Parenteral and Enteral Nutrition.Results. A strong significant correlation (r=1.000, P=0.01) between the volume of perioperative infusion therapy and the stage of postoperative intestinal failure was established.Conclusion. During performance of emergency surgeries, the volume of intra-operative infusion therapy rendered a direct influence on the postoperative bowel function. Optimization and application of a targeted corrective infusion therapy during the perioperative period promote earlier resolution of postoperative intestinal failure

Assessment of the dynamics of the physical and functional state of athletes of the highest category in the conditions of the COVID-19 pandemic based on the use of digital technologies

The aim of the study was to monitor the reaction of athletes to COVID-19 and to develop a methodology for monitoring the physical and functional condition of highly qualified basketball team players in the conditions of the COVID-19 pandemic. The relevance of the study lies in the fact that in professional sports today, a methodology for assessing the physical and functional state of athletes in the context of the COVID-19 pandemic is only being formed. Of particular interest is the application of digital technology, since it gives accurate and objective results. The technique developed in the course of the study can be used not only to analyze the condition of highly qualified basketball players, but also for athletes of other team sports volleyball, handball, football and others