'Theory for the enhanced induced magnetization in coupled magnetic trilayers in the presence of spin fluctuations'

Motivated by recent experiments, the effect of the interlayer exchange interaction $J_{inter}$ on the magnetic properties of coupled Co/Cu/Ni trilayers is studied theoretically. Here the Ni film has a lower Curie temperature $T_{C,\rm Ni}$ than the Co film in case of decoupled layers. We show that by taking into account magnetic fluctuations the interlayer coupling induces a strong magnetization for T\gtsim T_{C,\rm Ni} in the Ni film. For an increasing $J_{inter}$ the resonance-like peak of the longitudinal Ni susceptibility is shifted to larger temperatures, whereas its maximum value decreases strongly. A decreasing Ni film thickness enhances the induced Ni magnetization for T\gtsim T_{C,\rm Ni}. The measurements cannot be explained properly by a mean field estimate, which yields a ten times smaller effect. Thus, the observed magnetic properties indicate the strong effect of 2D magnetic fluctuations in these layered magnetic systems. The calculations are performed with the help of a Heisenberg Hamiltonian and a Green's function approach.Comment: 4 pages, 3 figure

Adenosine-regulated mechanisms in the pathogenesis of ventilation disorders in patients with pulmonary tuberculosis

Uncovering involvement of the purinergic system in the pathogenesis of ventilation disorders (VD) may provide additional information about the pathophysiological mechanisms leading to the development of VD in pulmonary tuberculosis (PT). The aim was to identify a relationship between the parameters of adenosine metabolism, inflammatory response and altered ventilation metabolism in PT patients. Materials and methods. Obstructive and mixed PT patients were assigned to subgroups with/without VD for assessing adenosine deaminase activity (ADA-1, 2) in serum, mononuclear cells, neutrophils; ecto-5’-nucleotidase (ecto-5’-NT); CD26 (dipeptidyl peptidase-4, DPP-4), phagocyte oxidative burst measured by NO generation. Results. PT patients showed decreased ADA-1 and CD26 (DPP-4), but increased ADA-2. Elevated intracellular adenosine concentration was found in mononuclear cells in patients lacking VD, whereas patients with mixed and obstructive VD — had it in neutrophils. Mononuclear cells of patients with PT lacking VD as well as with obstructive VD type had decreased NO3– concentration. Neutrophil hyperactivity was recorded in all groups of PT patients. Patients with PT lacking VD as well as with mixed VD type showed that the parameters of external respiration were associated with activity of extra-/intracellular ADA, whereas obstructive VD was caused by excessive formation of serum adenosine. Changes in respiratory function in PT were associated with decreased level of serum NO radicals, impaired nitrogen-dependent bactericidal phagocyte activity, and overproduced neutrophil oxygen radicals. Conclusion. Purinergic regulation is involved in regulating inflammatory and compensatory processes in PT patients as well as impaired ventilation efficiency. The most severe respiratory disorders observed in PT patients with mixed VD type are associated with the most prominent changes in nucleotidase activity, particularly ecto-ADA-2 and DPP-4/CD26

In-plane dipole coupling anisotropy of a square ferromagnetic Heisenberg monolayer

In this study we calculate the dipole-coupling-induced quartic in-plane anisotropy of a square ferromagnetic Heisenberg monolayer. This anisotropy increases with an increasing temperature, reaching its maximum value close to the Curie temperature of the system. At T=0 the system is isotropic, besides a small remaining anisotropy due to the zero-point motion of quantum mechanical spins. The reason for the dipole-coupling-induced anisotropy is the disturbance of the square spin lattice due to thermal fluctuations ('order-by-disorder' effect). For usual ferromagnets its strength is small as compared to other anisotropic contributions, and decreases by application of an external magnetic field. The results are obtained from a Heisenberg Hamiltonian by application of a mean field approach for a spin cluster, as well as from a many-body Green's function theory within the Tyablikov-decoupling (RPA).Comment: 6 pages, 2 figures, accepted for publication in RP

NITRIC OXIDE – BIOCHEMICAL MARKER OF TUBERCULOSIS PATHOGENESIS

Role of nitric oxide in the pathogenesis of pulmonary tuberculosis has been studied in 77 patients with new infiltrate pulmonary tuberculosis and 34 patients with fibrous cavernous pulmonary tuberculosis. The level of cumulative and endogenous nitrite depended on the clinical form of tuberculosis: in infiltrate pulmonary tuberculosis patients it was within the limits of reference ranges, and in fibrous cavernous pulmonary tuberculosis patients it was significantly lower. Results of statistical analysis point out at the significant homogeneity (monofunctionality) of the set of rates, defining the level of NO metabolites in blood serum in infiltrate pulmonary tuberculosis, namely: impact of adenosine deaminase, levels of α1-protease inhibitor, ceruleoplasmin and age. On the contrary in case of fibrous cavernous pulmonary tuberculosis the diverse (multi-functional) complexes were detected including clinical blood rates providing influence on the reduction of NO level in blood. Nitric oxide in the patients with both clinical forms of tuberculosis correlated with classical markers of system inflammatory response, thus nitric oxide can be regarded as an integral component of inflammatory response with potential evaluation of prognosis of specific lesions during follow-up of changes

Ten-year experience of transbronchial endosonography in single center

Objective Transbronchial endosonography (EBUS) is a relatively new method for diagnosing of the pathological condition of the thoracic organs. Analysis of 10 years of our experience in the use of transbronchial endosonography in a specialized center.Material and Methods During the period from April 2010 to April 2020, 756 transbronchial endosonographies were conducted on 756 patients. The studies were carried out for various indications: 1) Group 1 (483) – transbronchial puncture of the lymph nodes in order to obtain morphological confirmation of the etiology; 2) Group 2 (260) – staging of suspected or verified lung cancer to determine the descriptor N; 3) Group 3 (13) – a study that ended only with obtaining an endosonographic image. All patients underwent transbronchial endosonography using the special ultrasound bronchoscope EB-1970UK (Pentax Corp.) and the ultrasound scanner EUB 5000 Plus G OB/GYN – Vascular Ultrasound (HITACHI Corp.).Results General information content was 78%; verification of mediastinal lymphadenopathy was 72% (57, 79, 58% for smears, cytoblocks and smears + cytoblocks, cytoblocks vs smears + cytoblocks, p < 0.05). Verification of local changes in the mediastinum – 66%; verification of peribronchial tumor – 87%. Lung cancer staging – 87% (82, 88, 86% for smears, cytoblocks vs smears + cytoblocks, respectively, р > 0.05)Conclusion Тhe diagnostic utility of EBUS for the verification of mediastinal lymphadenopathy can range from 37,5 to 83% and rise with increasing experience for all persons involved. The use of cytoblocks showed the best results. The diagnostic utility of staging varies from 60 to 100% and does not depend on the method of processing the aspiration material

AUTOIMMUNE ORIGIN OF SARCOIDOSIS: DETERMINATION OF SPECIFIC IMMUNE COMPLEXES IN PATIENTS WITH RESPIRATORY SARCOIDOSIS

The etiology of sarcoidosis is not completely understood. A hypothesis exists about the relationship between sarcoidosis and a complex of pathological autoimmune reactions that occur under the influence of triggering factors. In this study, specific immune complexes in the blood plasma of patients have been determined, which can indirectly reveal the causes of the disease.The study included 33 patients with lung sarcoidosis (I group), compared to 24 healthy donors who served as a control group (II group). The patients underwent standard examination. Their blood plasma was investigated by the dynamic light scattering method with addition of tuberculosis antigens (ESAT-6/SFP-10) and “lung healthy tissue extract”. Statistical analysis was performed using the Statistica 7.0 program. Test results were considered significant at p < 0.05.Аccording to the data obtained, addition of ESAT-6/SFP-10 to patient’s blood plasma almost did not lead to the formation of immune complexes in most samples. Meanwhile, development of such complexes after addition of “lung tissue extract” was revealed in all the patients. The immune complexes were not detected in any donor from control group after stimulation with both kinds of antigens (p < 0.01).The data on distinct formation of immune complexes with the addition of “lung healthy tissue extract” in patients with lung sarcoidosis may be considered an indirect evidence for occurrence of autoimmune reaction under the influence of some pathogenic factors. Absence of de novo immune complex formation after addition of tuberculosis antigens (ESAT-6/SFP-10) makes it unlikely any direct effects of tuberculosis bacteria upon development of sarcoidosis

Возможность прогнозирования эффективности терапии у больных впервые выявленным инфильтративным туберкулезом легких по исходной активности аденозиндезаминазы и показателей воспалительного ответа

The objective: to evaluate the possibility of using the baseline activity of adenosine deaminase (ADA) to predict effectiveness of therapy in patients with new infiltrative pulmonary tuberculosis (IPTB).Subjects and Methods. Data of 121 patients with new infiltrative pulmonary tuberculosis were analyzed; patients were divided into groups according to therapy effectiveness.Results., The discriminant analysis of data of new infiltrative pulmonary tuberculosis patients made it possible to obtain adiscriminant function which included the activity of ADA, the concentration of haptoglobin (HP) and ceruloplasmin (CP) – parameters reflecting that severity of the disease and protective potential of the host.Conclusion. Analysis of ADA activity in combination with level of HP and CP allows the following: predicting effectiveness of the intensive phase of therapy before it begins in patients with new infiltrative pulmonary tuberculosis (with the accuracy of 77.0%); assuming that the reduction of ADA activity and inhibition of the inflammatory response may be useful for treatment of patients with new infiltrative pulmonary tuberculosis.Цель исследования: оценить возможность использования исходной активности аденозиндезаминазы (АДА) для прогнозирования эффективности терапии у больных впервые выявленным инфильтративным туберкулезом легких (ИТЛ).Материал и методы. Анализ данных проведен у 121 больного впервые выявленным ИТЛ в группах согласно эффективности терапии.Результаты. У больных впервые выявленным ИТЛ применение дискриминантного анализа позволило получить дискриминантную функцию, в которую вошли активность АДА, концентрация гаптоглобина (ГП) и церулоплазмина (ЦП) – показатели, отражающие тяжесть специфического процесса и защитные возможности организма больного.Заключение. Анализ активности АДА в комплексе с уровнем ГП и ЦП позволяет: прогнозировать эффективность интенсивной фазы терапии до ее начала у больных впервые выявленным ИТЛ (с точностью 77,0%); предположить, что снижение активности АДА и ингибирование воспалительной реакции может быть полезным для лечения больных впервые выявленным ИТЛ

МЛУ-туберкулез и ВИЧ-инфекция в Северо-Западном федеральном округе

The objective of the study: to study changes in MDR tuberculosis incidence and prevalence among patients with HIV infection in the North-Western Federal District and its regions in 2007-2018.Subjects and methods. The data from FSN Form No. 61 on Information on HIV Infected Patients Contingents for 2007-2018, materials of Federal Research Institute for Health Organization and Informatics by the Russian Ministry of Health, information from tables additionally developed by the authors were used. Epidemiological and statistical methods were applied; the differences between the variables were established by the Fisher coefficient based on the Statistica software.Results. The increase in the incidence of TB/HIV co-infection is the highest in regions with the low cumulation of HIV infection: Arkhangelsk, Pskov Regions and the Komi Republic. In 2018, MDR TB among HIV patients with HIV was the most prevalent in Leningrad Region (37.7%), the Komi Republic (32.2%) and Novgorod Region (29.3%), while in the Republic of Karelia, there was not a single case of MDR TB detected among HIV patients, in Pskov Region - 2.4% of cases. The efficacy of tuberculosis chemotherapy by regimens IV-V among the MDR TB/HIV cohort was statistically significantly lower than that of the entire MDR TB cohort: 41.4% versus 61.5% (p < 0.04).Цель исследования: изучение динамики заболеваемости и распространенности МЛУ-туберкулеза среди пациентов с ВИЧ-инфекцией в СЗФО и его регионах за 2007-2018 гг.Материалы и методы. Использованы данные из формы ФСН № 61 «Сведения о контингентах больных ВИЧ-инфекцией» за 2007-2018 гг., материалы ФГБУ «ЦНИИОИЗ» Минздрава России, информация из дополнительно разработанных авторами таблиц. Применялись методы эпидемиологические, статистические, различия между переменными устанавливались по коэффициенту Фишера на базе программы Statistica.Результаты. Рост заболеваемости туберкулезом в сочетании с ВИЧ-инфекцией наиболее высок в регионах с низкой кумуляцией ВИЧ-инфекции: Архангельской, Псковской областях и Республике Коми. МЛУ-ТБ среди пациентов с ВИЧ-инфекцией в 2018 г. был наиболее распространен в Ленинградской области (37,7%), Республике Коми (32,2%) и Новгородской области (29,3%), в Республике Карелия не было выявлено ни одного случая МЛУ-ТБ среди пациентов с ВИЧ-инфекцией, в Псковской области - 2,4% случаев. Эффективность курса химиотерапии туберкулеза по IV-V режимам среди когорты с МЛУ-ТБ в сочетании с ВИЧ-инфекцией была статистически значимо ниже, чем всей когорты с МЛУ-ТБ: 41,4% против 61,5% (p < 0,04)