Synthesis of Novel 1,2,3-Thiadiazoles

This work was supported by the Russian Foundation for Basic Research, project 17-03-00641

Exposure of vanadium as a factor of adverse activation of lymphocytes

We have estimated effect of vanadium influence on apoptosis of peripheral blood lymphocytes among workers. Immunologic assessment have allowed establishing that people working under the conditions of vanadium exposure have significantly increased quantity of annexin-positive cells indicating apoptosis in comparison with a reference group of people. We have identified statistically significant adverse mobilization of lymphocytes in respondents who have been working under conditions of the hazardous industry over 10 years. Therefore, the level and duration of the vanadium exposure influenced by the length of em plopent increase the immune system dysfunction degree.Проведена оценка влияния ванадия на клеточную гибель лимфоцитов периферической крови у работающих. Оценка иммунного статуса позволила установить, что у работающих в условиях экспозиции ванадием количество аннексин-позитивных клеток, свидетельствующих об апоптозе, достоверно повышается по отношению к группе сравнения. Выявлена статистически значимая негативная активация лимфоцитов у обследуемых, чей стаж в условиях вредного производства превышал 10 лет. Таким образом, уровень и длительность экспозиции ванадием, определяемая стажем работы, усугубляет степень дисфункции иммунной системы

EXPERIMENTAL MODELING OF APOPTOSIS UNDER CONDITIONS OF STABLE STRONTIUM EXPOSURE

Apoptosis is defined as a highly regulated form of programmed cell death with typical morphological and biochemical features. A variety of factors, including heavy metals, may influence the intensity of programmed cell death. The aim of the work was to simulate apoptosis in an in vitrosystem under the conditions of stable strontium exposure. The children’s population consuming drinking water with high strontium (Sr2+) content (n = 49) was observed. The level of lymphocyte apoptosis was determined with flow cytometry technique, by means of labeled annexin V-FITC conjugate (AnnV-FITC) and propidium iodide (PI) staining. AnnV-FITC+PI- cells were regarded as early apoptotic forms, whereas late apoptotic and/or necrotic cells were AnnV-FITC+PI+. The isolated leukocytes were incubated with Sr2+ at a concentration of 7.0 mg/l, the maximal permitted concentration (MPC) for water of aqueous objects, for 4 hours at 37 ºC. Expression of CD95 and p53 apoptosis markers was performed by flow cytometry using labeled monoclonal antibodies.In vitroexposure to strontium was associated with significantly decreased expression of apoptosisregulating factors, i.e., membrane marker CD95 and intracellular transcription protein p53, 1.56- and 1.68-fold, respectively. Meanwhile, we revealed a significantly (4.68-fold) decreased amounts of AnnV-FITC+PI--cells, as well as a statistically significant (1.35-fold) increase of the AnnV-FITC+PI+-cells. Moreover, the amounts of AnnV-FITC+ PI--lymphocytes in all samples were below the physiological ranges and control values. The number of samples with higher contents of AnnV-FITC+PI+-lymphocyte exceeding the established standards and control values, was 30.8%. Thus, it has been experimentally proven that strontium, at a concentration corresponding to MPC for water objects may significantly inhibit cell death along apoptotic pathways, with switching to necrotic cell death mechanisms, according to phosphatidylserine contents, as detected by annexin V binding test. The data have revealed an ability of strontium to have a significant effect upon the parameters of regulation and maintenance of cellular homeostasis, by influencing the apoptosis intensity, due to shifting a balance towards necrosis and reducing expression of apoptosis-regulating factors. The results of this study may be used in order to identify some marker indexes of immune disorders potentially induced by external influence of strontium upon human health under specific environmental factors

Structure of an archaeal PCNA1-PCNA2-FEN1 complex: elucidating PCNA subunit and client enzyme specificity.

The archaeal/eukaryotic proliferating cell nuclear antigen (PCNA) toroidal clamp interacts with a host of DNA modifying enzymes, providing a stable anchorage and enhancing their respective processivities. Given the broad range of enzymes with which PCNA has been shown to interact, relatively little is known about the mode of assembly of functionally meaningful combinations of enzymes on the PCNA clamp. We have determined the X-ray crystal structure of the Sulfolobus solfataricus PCNA1-PCNA2 heterodimer, bound to a single copy of the flap endonuclease FEN1 at 2.9 A resolution. We demonstrate the specificity of interaction of the PCNA subunits to form the PCNA1-PCNA2-PCNA3 heterotrimer, as well as providing a rationale for the specific interaction of the C-terminal PIP-box motif of FEN1 for the PCNA1 subunit. The structure explains the specificity of the individual archaeal PCNA subunits for selected repair enzyme 'clients', and provides insights into the co-ordinated assembly of sequential enzymatic steps in PCNA-scaffolded DNA repair cascades

Hydroxylated aromatic hydrocarbons and the cytokine regulation of apoptosis

Organic compounds, at concentrations exceeding their reference ranges, may influence the production of physiological regulators of the cell cycle. The aim of the study was to assess the influence of hydroxylated aromatic hydrocarbons on the cytokine regulation of apoptosis in insulation workers of a chemical enterprise. The organic compounds (phenol, o-cresol, m-cresol, p-cresol) were determined in biological media using capillary gas chromatography. The mediators of intercellular immune regulation - cytokine profile markers (IL6, TNFa, INFy) - were identified by ELISA testing, the level of TNFRI expression was measured using cytofluorometry analysis. The assessment of the cytokine status shows that the examined workers, when exposed to high levels of phenol-containing compounds, demonstrated a credible decrease in the production of the proapoptotic mediators of cellular regulation (TNFa, IFNy) (p<0.05) and a statistically significant reduction in TNFRI expression on lymphocytes (p<0.05). The findings prove the contribution of phenols in the modification of the cytokine status in the workers. Taking into account the specific aromatic hydrocarbons influence on the expression of the physiological regulators of the cell cycle, the impact of phenols may cause immune dysfunction in chemical enterprise workers.Органические соединения в превышающих референтные значения концентрациях могут модулировать продукцию физиологических регуляторов клеточного цикла. Цель работы - оценить влияние гидроксилированных ароматических углеводородов на цитокиновую регуляцию апоптоза у изолировщиков химического производства. Определение органических соединений (фенол, о-крезол, м-крезол, п-крезол) в биосредах выполнялось методом капиллярной газовой хроматографии. Идентификацию медиаторов межклеточной иммунной регуляции - маркеров цитокинового профиля (IL6, TNFa, INFy) осуществляли методом иммуноферментного анализа, для определения уровня экспрессии рецептора TNFRI использовали цитофлюориметрический метод. Оценка цитокинового статуса зафиксировала, что у обследуемых работающих в условиях повышенной экспозиции фенолсодержащих соединений достоверно снижена продукция проапоптотических медиаторов клеточной регуляции (TNFa, IFNy) (р<0,05) и статистически значимо понижена экспрессия рецептора к фактору некроза опухоли на лимфоцитах (р<0,05). Результаты исследований подтверждают существующий вклад фенолов в модификацию цитокинового статуса работающих. Учитывая специфическое влияние гидроксилированных ароматических углеводородов на экспрессию физиологических регуляторов клеточного цикла, воздействие фенолов может стать пусковым механизмом дисфункции иммунной системы в условиях химического производства

DNA polymerase δ-dependent repair of DNA single strand breaks containing 3′-end proximal lesions

Base excision repair (BER) is the major pathway for the repair of simple, non-bulky lesions in DNA that is initiated by a damage-specific DNA glycosylase. Several human DNA glycosylases exist that efficiently excise numerous types of lesions, although the close proximity of a single strand break (SSB) to a DNA adduct can have a profound effect on both BER and SSB repair. We recently reported that DNA lesions located as a second nucleotide 5′-upstream to a DNA SSB are resistant to DNA glycosylase activity and this study further examines the processing of these ‘complex’ lesions. We first demonstrated that the damaged base should be excised before SSB repair can occur, since it impaired processing of the SSB by the BER enzymes, DNA ligase IIIα and DNA polymerase β. Using human whole cell extracts, we next isolated the major activity against DNA lesions located as a second nucleotide 5′-upstream to a DNA SSB and identified it as DNA polymerase δ (Pol δ). Using recombinant protein we confirmed that the 3′-5′-exonuclease activity of Pol δ can efficiently remove these DNA lesions. Furthermore, we demonstrated that mouse embryonic fibroblasts, deficient in the exonuclease activity of Pol δ are partially deficient in the repair of these ‘complex’ lesions, demonstrating the importance of Pol δ during the repair of DNA lesions in close proximity to a DNA SSB, typical of those induced by ionizing radiation

Water/Alkali-Catalyzed Reactions of Azides with 2-Cyanothioacetamides. Eco-Friendly Synthesis of Monocyclic and Bicyclic 1,2,3-Thiadiazole-4-carbimidamides and 5-Amino-1,2,3-triazole-4-carbothioamides

The reactions of thioamides with azides in water were studied. It was reliably shown that the reaction of 2-cyanothioacetamides 1 with various types of azides 2 in water in the presence of alkali presents an efficient, general, one-step, atom-economic, and eco-friendly method for the synthesis of 1,2,3-thiadiazol-4-carbimidamides 5 and 1,2,3-triazole-4-carbothioamides 4. This method can be extended to the one-pot reaction of sulfonyl chlorides and 6-chloropyrimidines 2′o with sodium azide, leading to final products in higher yields, that is, avoiding the isolation of unsafe sulfonyl azides. The method was furthermore applied to the reaction of N,N′-bis-(2-cyanothiocarbonyl)pyrazine 1h with sulfonyl azides to afford bicyclic 1,2,3-thiadiazoles 8 and 1,2,3-triazoles 9 connected via a 1,1′-piperazinyl linker. 2-Cyanothioacetamides 1 were also shown to react with aromatic azides in water in the presence of alkali to afford 1-aryl-5-amino-1,2,3-triazole-4-carbothioamides 11. In contrast to aromatic azides and similarly to sulfonyl azides, 6-azidopyrimidine-2,4-diones 2o-q react with cyanothioacetamides to form N-pyrimidin-6-yl-5-dialkylamino-1,2,3-thiadiazole-4-N-l-carbimidamides 12. A mechanism was proposed to rationalize the role of water in changing the reactivity of azides toward 2-cyanothioacetamides. Copyright © 2019 American Chemical Society.We gratefully acknowledge financial support of this work by the Russian Science Foundation (18-13-00161)

The interdependence of external signs of connective tissue dysplasia and the formation of the female pelvis.

45 students of the Ural State Medical University were researched. The correlation of anthropometric indices and external signs of connective tissue dysplasia with the size of the female pelvis is estimated. They revealed smaller pelviometric indices for girls with low height, weight, length of hand and foot, and signs of joint hypermobility.Проведено исследование 45 студенток Уральского государственного медицинского университета. Оценена корреляция антропометрических показателей и внешних признаков дисплазии соединительной ткани с размерами женского таза. Выявили меньшие пельвиометрические показатели у девушек с низким ростом, весом, длиной кисти и стопы, признаками гипермобильности суставов

The interdependence of external signs of connective tissue dysplasia and the formation of the female pelvis

45 students of the Ural State Medical University were researched. The correlation of anthropometric indices and external signs of connective tissue dysplasia with the size of the female pelvis is estimated. They revealed smaller pelviometric indices for girls with low height, weight, length of hand and foot, and signs of joint hypermobility.В статье рассмотрены вопросы касательно показаний к назначению гестагенов во время беременности. Проведено когортное поперечное исследование, включившее 128 беременных женщин, взятых методом сплошной выборки, на разных сроках гестации, среди которых выделена группа пациенток, получавших гестагенную поддержку. Определена частота назначения гестагенов и структура показаний к их применению во время беременности