Quantum-chemical study of the effects of noncovalent interactions on the nuclear magnetic screening constants of pyrimidine base associates

The effects of weak noncovalent interactions on the nuclear magnetic screening (NMS) constants (σ 1H), (σ 13C) and charge distribution (q t ) on atoms in van der Waals model associates of unsubstituted and substituted pyrimidines and substituted uracil are considered. The NMS constants were calculated by the UB3LYP/6-31G(d,p) with GIAO functions. The correlation dependences of the 1H and 13C σ constants on the charge q on atoms whre constructed. It were shown that they can be represented as polynomials that include the terms that are linear and quadratic relative to the charge. The relations obtained in this way are similar in form and close in magnitude to the coefficients of the known Buckingham and Augspurger functions that describe the electric field effects on the nuclear magnetic screening constants. It was found that the coefficients in these polynomials have a definite physical sense in that they characterize nuclear magnetic screening and the "screening polarizability" tensor in the unperturbed molecule and associate, respectively. The NMS constants and charge distribution in pyrimidine base associates and accordingly the coefficients that reflect their values in polynomials depend on the form, size, and composition of the associate and can vary significantly depending on the position of the pyrimidine base in the associate. © 2007 Springer Science+Business Media, Inc

The role of cytokines in the mechanism of development of chronic generalized periodontitis

The article presents information on the role of cytokines in the pathogenetic mechanisms of development of chronic inflammation in periodontal tissues. The aim of the study was the investigation of the mechanisms of cytokine regulation in chronic inflammatory process in periodontal tissues in patients with chronic generalized periodontitis and brakesman. Methodology. The object of study steel 317 patients with periodontal disease easy and moderate severity. Investigated in oral fluid range of cytokines to determine their role in the pathogenetic mechanisms of development of chronic inflammation in periodontal tissues. The control group consisted of 112 people. Both groups were matched for age and sex. Results. Among patients with chronic generalized periodontitis were identified statisticheski significant imbalance of Pro - and anti-inflammatory cytokines. State changes in the status of cytokines has allowed to determine the informative criteria with prognathic value in the oral fluid, contributing to reduction in inflammation. Conclusions. The revealed changes testify to the breakdown of adaptive processes and the development of clinical symptoms of periodontal disease.В статье представлены сведения о роли цитокинов в патогенетических механизмах развития хронического воспаления в тканях пародонта. Целью исследования послужило изучение механизмов цитокиновой регуляции при хроническом воспалительном процессе в тканях пародонта у пациентов с хроническим генерализованным пародонтитом и брукизмом. Методология. Объектом изучения стали 317 пациентов, имеющих заболевание пародонта легкой и средней степени тяжести. Исследовали в ротовой жидкости спектр цитокинов для выявления их роли в патогенетических механизмах развития хронического воспаления в тканях пародонта. Группу контроля составили 112 человек. Обе группы были сопоставимы по возрасту и полу. Результаты. Среди пациентов с хроническим генерализованным пародонтитом был выявлен статитически значимый дисбаланс про- и противовоспалительных цитокинов. Изменения состояния в их статусе цитокинов позволили определить информативные критерии обладающие прогнатической ценностью в ротовой жидкости, способствующие купированию воспалительных процессов. Выводы. Выявленные изменения свидетельствуют о срыве адаптационных процессов и развитии клинических симптомов заболевания пародонта

Quantum-chemical study of the effects of noncovalent interactions on the nuclear magnetic screening constants of pyrimidine base associates

The effects of weak noncovalent interactions on the nuclear magnetic screening (NMS) constants (σ 1H), (σ 13C) and charge distribution (q t ) on atoms in van der Waals model associates of unsubstituted and substituted pyrimidines and substituted uracil are considered. The NMS constants were calculated by the UB3LYP/6-31G(d,p) with GIAO functions. The correlation dependences of the 1H and 13C σ constants on the charge q on atoms whre constructed. It were shown that they can be represented as polynomials that include the terms that are linear and quadratic relative to the charge. The relations obtained in this way are similar in form and close in magnitude to the coefficients of the known Buckingham and Augspurger functions that describe the electric field effects on the nuclear magnetic screening constants. It was found that the coefficients in these polynomials have a definite physical sense in that they characterize nuclear magnetic screening and the "screening polarizability" tensor in the unperturbed molecule and associate, respectively. The NMS constants and charge distribution in pyrimidine base associates and accordingly the coefficients that reflect their values in polynomials depend on the form, size, and composition of the associate and can vary significantly depending on the position of the pyrimidine base in the associate. © 2007 Springer Science+Business Media, Inc

Quantum-chemical study of the effects of noncovalent interactions on the nuclear magnetic screening constants of pyrimidine base associates

The effects of weak noncovalent interactions on the nuclear magnetic screening (NMS) constants (σ 1H), (σ 13C) and charge distribution (q t ) on atoms in van der Waals model associates of unsubstituted and substituted pyrimidines and substituted uracil are considered. The NMS constants were calculated by the UB3LYP/6-31G(d,p) with GIAO functions. The correlation dependences of the 1H and 13C σ constants on the charge q on atoms whre constructed. It were shown that they can be represented as polynomials that include the terms that are linear and quadratic relative to the charge. The relations obtained in this way are similar in form and close in magnitude to the coefficients of the known Buckingham and Augspurger functions that describe the electric field effects on the nuclear magnetic screening constants. It was found that the coefficients in these polynomials have a definite physical sense in that they characterize nuclear magnetic screening and the "screening polarizability" tensor in the unperturbed molecule and associate, respectively. The NMS constants and charge distribution in pyrimidine base associates and accordingly the coefficients that reflect their values in polynomials depend on the form, size, and composition of the associate and can vary significantly depending on the position of the pyrimidine base in the associate. © 2007 Springer Science+Business Media, Inc

On likely linkage between dissociative electron attachment and biological effects produced by xenobiotics

A possible correlation between electron acceptor properties, in particular, dissociative electron attachment (DEA) and biological activity for a series of xenobiotic species (organic pollutants, polyphenolic antioxidants, and ascorbic acid) is reported. Formation and decay of temporary negative ions (TNIs) are studied using electron transmission and DEA spectroscopies. Experimental findings are assigned with the support of density functional theory calculations and are discussed in connection with the effects produced by these compounds in living cells. The basic ideas of the present study are derived from the work published in the earlier 60th of the XX century by A. Szent-Györgyi [1,2] and J. Lovelock [3]. Likely sources of electrons able to interact with xenobiotic molecules to form TNIs under cellular conditions are tentatively associated with mitochondria and cytochrome P450 enzymes. The formed TNIs are supposed to decay via the DEA mechanism producing negatively charged and neutral fragments, in analogy with those observed by DEA spectroscopy under gas-phase conditions. Electrochemical studies of reductive dehalogenation [4] and dehydrogenation [5] in solution demonstrate that TNIs can dissociate in condensed environment instead of dissipating their excess energy. Preliminary conclusions about a correlation between DEA and biochemical processes are summarized

COOPERATIVE APPLICATION OF ENDOPHYTIC STRAINS OF BEAUVERIA BASSIANA UFA-2 AND BACILLUS SUBTILIS 26Д FOR COMPREHENSIVE DEFENSE OF POTATO

Endophytic habitation of Beauveria bassiana Ufa-2 and Bacillus subtilis 24D was demonstrated. Presence of these strains decreased the level of late blight symptoms and Colorado potato beetle eating of plants.Работа выполнена при поддержке гранта двухлетних прикладных научных исследований, направленных на создание продукции и технологий, по приоритетному направлению «Науки о жизни» в рамках мероприятия 1.2 Программы Министерства образования и науки РФ № 14.604.21.0016