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Введение. Одна из главнейших проблем современной трансплантологии – иммунологическая дисфункция трансплантата, частота развития которой достигает 40%. Пункционная биопсия в 2,2% случаев сопряжена с развитием осложнений и может привести к летальному исходу. Цель исследования – разработка методики неинвазивной диагностики отторжения трансплантата печени в отдаленном периоде после операции с использованием терминально-дифференцированных эффекторных CD8+Т-лимфоцитов. Материал и методы. Проведено пилотное одноцентровое обсервационное ретроспективное случай-контроль исследование, включающее 45 реципиентов после ортотопической трансплантации печени. По клиническому течению послеоперационного периода пациенты стратифицировались на 2 группы в зависимости от наличия эпизодов отторжения в трансплантате. Все пациенты после трансплантации получали иммуносупрессивную терапию. Иммунофенотипы реципиентов определялись методом проточной цитофлоуметрии. Всем пациентам была выполнена пункционная биопсия трансплантата. Результаты. Результаты исследования биоптатов трансплантатов печени показали, что 14 пациентов (31%) из 45 имели морфологические признаки отторжения. У пациентов с отторжением был достоверно более высокий уровень абсолютного количества СD8+ Тemra-клеток, что составило 0,23 (0,14; 0,38) ×109/л по сравнению с пациентами без отторжения – 0,09 (0,034; 0,16)×109/л (р=0,034). Результаты ROC- анализа показали, что наиболее оптимальный порог отсечения уровня СD8+ Тemra-лимфоцитов при диагностике иммунологической дисфункции трансплантата печени в отдаленном периоде составил 0,1882×109/л, чувствительность и специфичность при данном пороге отсечения составила 73,33 (95% ДИ: 44,9-92,0) и 96,55 (95% ДИ: 82,2-99,4,) соответственно. Выводы. Увеличение абсолютной численности терминально-дифференцированных эффекторных CD8+ Т-лимфоцитов является диагностическим критерием у пациентов с иммунологической дисфункцией трансплантата в позднем посттрансплантационном периоде. Высокая чувствительность и специфичность порога отсечения абсолютного количества CD8+ Тemra-лимфоцитов у пациентов после трансплантации печени и достоверная разница между количеством клеток у пациентов с нормальным послеоперационным течением, имеющих иммунологическую дисфункцию трансплантата, позволяет рассматривать субпопуляцию Т-лимфоцитов как прогностический биомаркер отторжения в позднем посттрансплантационном периоде. Корреляция этого показателя с результатами морфологического исследования делает его альтернативным и, главное, безопасным неинвазивным способом ранней диагностики отторжения.

Background. Immune-mediated graft dysfunction with the prevalence of 40% is one of the main problems of modern transplantology. Although percutaneous liver graft biopsy is associated with the development of different complications occurring in 2,2% of cases and can also lead to fatal outcome Objective – to develop a noninvasive method of graft dysfunction diagnostics in the late post-transplant period using terminally differentiated effector CD8+ T-lymphocytes. Material and methods. There was carried out a single center observational retrospective case-control pilot study, including 45 recipients after orthotopic liver transplantation. According to the postoperative clinical course the patients were stratified into 2 groups depending on the presence of graft rejection episodes. All patients got immunosuppressive therapy after liver transplantation. Immunophenotypes of the recipients were determined by flow cytometry method. Percutaneous liver graft biopsy was performed in all patients, the results of histological examination were evaluated according to the international Banff schema for grading liver allograft rejection. Results. The results of liver biopsies showed that 14 (31%) out of 45 patients had morphological signs of rejection. The patients with rejection had a reliably higher level of CD8+ Temra cells absolute number (0,23 (0,14;0,38) x 109/l) in comparison to those without rejection (0,09 (0,034;0,16) x 109/l (p=0,034)). The results of ROC-analysis have shown that the most optimal cut-off threshold of CD8+ T-lymphocytes level in immune-mediated graft dysfunction diagnostics in the late post-transplant period is 0,1882x109/l; sensitivity and specificity in this case being 73,33 (95%; 44,9-92,0) and 96,55 (95%; 82,2-99,4) respectively. Conclusions. The increase of terminally differentiated effector CD8+ T-lymphocytes absolute number has diagnostic importance in patients with immune-mediated graft dysfunction in the late post-transplant period. High sensitivity and specificity of cut-off threshold of CD8+ Temra lymphocytes absolute number in patients after liver transplantation as well as reliable difference between cell number in patients with normal postoperative period and in patients with immune-mediated graft dysfunction allow considering T-lymphocyte subpopulation as a rejection predictor in the late post-transplant period. The correlation between CD8+ T-lymphocyte absolute number and the results of histological examination makes the former an alternative and, what is more, safe noninvasive method in early diagnostics of liver graft rejection.

The title salt, C8H12NO+·C7H10NO5−, crystallizes in two polymorphic modifications,viz.monoclinic (M) and orthorhombic (O). The crystal structures of both polymorphic modifications have been established from laboratory powder diffraction data. The crystal packing motifs in the two polymorphs are different, but the conformations of the anions are generally similar. InM, the anions are linked by pairs of hydrogen bonds of the N—H...O and O—H...O types into chains along theb-axis direction, and neighbouring molecules within the chain are related by the 21screw axis. The cations link these chainsviaO—H...O and N—H...O hydrogen bonds into layers parallel to (001). InO, the anions are linked by O—H...O hydrogen bonds into helices along [001], and neighbouring molecules within the helix are related by the 21screw axis. The neighbouring helical turns are linked by N—H...O hydrogen bonds. The cations link the helicesviaO—H...O and N—H...O hydrogen bonds, thus forming a three-dimensional network.

Context. The international whole earth blazar telescope (WEBT) consortium planned and carried out three days of intensive micro-variability observations of S5 0716+714 from February 22, 2009 to February 25, 2009. This object was chosen due to its bright apparent magnitude range, its high declination, and its very large duty cycle for micro-variations. Aims. We report here on the long continuous optical micro-variability light curve of 0716+714 obtained during the multi-site observing campaign during which the Blazar showed almost constant variability over a 0.5 magnitude range. The resulting light curve is presented here for the first time. Observations from participating observatories were corrected for instrumental diff?erences and combined to construct the overall smoothed light curve. Methods. Thirty-six observatories in sixteen countries participated in this continuous monitoring program and twenty of them submitted data for compilation into a continuous light curve. The light curve was analyzed using several techniques including Fourier transform, Wavelet and noise analysis techniques. Those results led us to model the light curve by attributing the variations to a series of synchrotron pulses. Results. We have interpreted the observed microvariations in this extended light curve in terms of a new model consisting of individual stochastic pulses due to cells in a turbulent jet which are energized by a passing shock and cool by means of synchrotron emission. We obtained an excellent fit to the 72-hour light curve with the synchrotron pulse model.

One of the main problems encountered in development of cemented carbides is obtaining the optimum combination of hardness, wear resistance, high-temperature strength, and heat resistance with toughness of the material. Frequently it is solved by creation of a structure in which each refractory particle is surrounded by a layer of binder metal. Methods of liquid-phase sintering and self-propagating high-temperature synthesis (SHS) with subsequent strong compacting of the reaction products may be used for this purpose. The properties of materials produced by this method are determined primarily by the properties of the metal binder.

We present the first results from a high sampling rate, multi-month reverberation mapping campaign undertaken primarily at MDM Observatory with supporting observations from telescopes around the world. The primary goal of this campaign was to obtain either new or improved Hbeta reverberation lag measurements for several relatively low luminosity AGNs. We feature results for NGC 4051 here because, until now, this object has been a significant outlier from AGN scaling relationships, e.g., it was previously a ~2-3sigma outlier on the relationship between the broad-line region (BLR) radius and the optical continuum luminosity - the R_BLR-L relationship. Our new measurements of the lag time between variations in the continuum and Hbeta emission line made from spectroscopic monitoring of NGC 4051 lead to a measured BLR radius of R_BLR = 1.87 (+0.54 -0.50) light days and black hole mass of M_BH = 1.73 (+0.55 -0.52) x 10^6 M_sun. This radius is consistent with that expected from the R_BLR-L relationship, based on the present luminosity of NGC 4051 and the most current calibration of the relation by Bentz et al. (2009a). We also present a preliminary look at velocity-resolved Hbeta light curves and time delay measurements, although we are unable to reconstruct an unambiguous velocity-resolved reverberation signal., Comment: 38 pages, 7 figures, accepted for publication in ApJ, changes from v1 reflect suggestions from anonymous referee

(Abridged) OJ287 is a BL Lac object that has shown double-peaked bursts at regular intervals of ~12 yr during the last ~40 yr. We analyse optical photopolarimetric monitoring data from 2005-2009, during which the latest double-peaked outburst occurred. The aim of this study is twofold: firstly, we aim to analyse variability patterns and statistical properties of the optical polarization light-curve. We find a strong preferred position angle in optical polarization. The preferred position angle can be explained by separating the jet emission into two components: an optical polarization core and chaotic jet emission. The optical polarization core is stable on time scales of years and can be explained as emission from an underlying quiescent jet component. The chaotic jet emission sometimes exhibits a circular movement in the Stokes plane. We interpret these events as a shock front moving forwards and backwards in the jet, swiping through a helical magnetic field. Secondly, we use our data to assess different binary black hole models proposed to explain the regularly appearing double-peaked bursts in OJ287. We compose a list of requirements a model has to fulfil. The list includes not only characteristics of the light-curve but also other properties of OJ287, such as the black hole mass and restrictions on accretion flow properties. We rate all existing models using this list and conclude that none of the models is able to explain all observations. We discuss possible new explanations and propose a new approach to understanding OJ287. We suggest that both the double-peaked bursts and the evolution of the optical polarization position angle could be explained as a sign of resonant accretion of magnetic field lines, a 'magnetic breathing' of the disc., Comment: Accepted for publication in MNRAS (26 pages, 24 figures, 4 tables)

A special antiglare protective optical filter with antireflection coating, antiglare structure, UV protection layer, electromagnetic interference shield for rugged active matrix liquid display is described.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.