The use of an antibacterial implant in the treatment of periprosthetic infection in an HIV-positive patient

Background: The frequency of occurrence of infectious complications after hip arthroplasty in HIV-infected patients is extremely high. Revision arthroplasty for periprosthetic infection is the leader (64%) among the causes of early revision interventions. The search for ways to increase the efficiency of the sanitizing stage of treatment due to antibacterial coatings of the endoprosthesis components continues.Objective: Demonstration of a clinical case of treatment of periprosthetic infection in an HIV-positive patient using a spacer and a femoral component of a hip joint endoprosthesis coated with linear Sp1 carbon chains and silver. 123 months after hip arthroplasty for stage 3 dysplastic coxarthrosis in HIV-positive patient of 42 years old developed an instability of the acetabular component with the growth of Staphylococcus aureus in punctates. A revision was performed with the removal of the endoprosthesis and the installation of an articulating spacer with the addition of antibiotics. 12 weeks later, a recurrence of periprosthetic infection occurred, and Enterococcus faecalis was detected in punctates. During re-endoprosthetics, there was an installation of an articulating spacer covered with a two-dimensionally ordered linear-chain carbon doped with silver, based on the Zimmer CPT femoral component and bone cement with antibiotics addition. After 3 months, the second stage of revision arthroplasty was performed with implantation of an individual acetabular component and a femoral component coated with two-dimensionally ordered linear-chain carbon doped with silver.Conclusion: 4 months after the operation the patient returned to work, 12 months later the functional results were satisfactory. The use of components coated with two-dimensionally ordered linear-chain carbon doped with silver in an HIV-positive patient with recurrent periprosthetic infection made it possible to stop the infectious process, improve limb function and the quality of life

Ultra-High Energy Cosmic Ray production in the polar cap regions of black hole magnetospheres

We develop a model of ultra-high energy cosmic ray (UHECR) production via acceleration in a rotation-induced electric field in vacuum gaps in the magnetospheres of supermassive black holes (BH). We show that if the poloidal magnetic field near the BH horizon is misaligned with the BH rotation axis, charged particles, which initially spiral into the BH hole along the equatorial plane, penetrate into the regions above the BH "polar caps" and are ejected with high energies to infinity. We show that in such a model acceleration of protons near a BH of typical mass 3e8 solar masses is possible only if the magnetic field is almost aligned with the BH rotation axis. We find that the power of anisotropic electromagnetic emission from an UHECR source near a supermassive BH should be at least 10-100 times larger then UHECR power of the source. This implies that if the number of UHECR sources within the 100 Mpc sphere is ~100, the power of electromagnetic emission which accompanies proton acceleration in each source, $10^{42-43}$ erg/s, is comparable to the typical luminosities of active galactic nuclei (AGN) in the local Universe. We also explore the acceleration of heavy nuclei, for which the constraints on the electromagnetic luminosity and on the alignment of magnetic field in the gap are relaxed

FGF4 Independent Derivation of Trophoblast Stem Cells from the Common Vole

The derivation of stable multipotent trophoblast stem (TS) cell lines from preimplantation, and early postimplantation mouse embryos has been reported previously. FGF4, and its receptor FGFR2, have been identified as embryonic signaling factors responsible for the maintenance of the undifferentiated state of multipotent TS cells. Here we report the derivation of stable TS-like cell lines from the vole M. rossiaemeridionalis, in the absence of FGF4 and heparin. Vole TS-like cells are similar to murine TS cells with respect to their morphology, transcription factor gene expression and differentiation in vitro into derivatives of the trophectoderm lineage, and with respect to their ability to invade and erode host tissues, forming haemorrhagic tumours after subcutaneous injection into nude mice. Moreover, vole TS-like cells carry an inactive paternal X chromosome, indicating that they have undergone imprinted X inactivation, which is characteristic of the trophoblast lineage. Our results indicate that an alternative signaling pathway may be responsible for the establishment and stable proliferation of vole TS-like cells

Матриксные металлопротеиназы и белки теплового шока на внеклеточных везикулах у больных колоректальным раком: связь с метаболическим статусом

Introduction. In most patients with colorectal cancer (CRC), the tumor develops against the background of metabolically healthy obesity or metabolic syndrome (more than 60 % of patients), the key pathogenetic moment of which is developing hyperinsulinemia. Metabolic changes are also characteristic of patients with colon polyps (CP), which are currently considered as the most significant precancerous diseases. It has been shown that fractions of small extracellular vesicles (EVs) of adipocyte origin are specifically enriched in extracellular matrix proteins, including matrix metalloproteinases (MMPs), chaperones, and some metabolic enzymes involved in the synthesis of lipids and carbohydrates. This was the reason for choosing exosomal markers in our study. Comparison of protein expression on CD9- and FABP-4 positive vesicles will be useful to explain some clinical issues, such as the effectiveness of thermoradiotherapy or radiotherapy in obese CRC patients; for a more substantiated search for vesicular prognostic markers in obese cancer patients. However, taking into account the lack of data in the literature on the level of MMPs and HSPs expression in the composition of the total pool of EVs and in the composition of FABP4-positive EVs in patients with PTC and CRC patients, the aim of the work was formulated.Aim. Study of the level of MMPs and heat shock proteins (HSPs) on CD9- and FABP4-positive EVs in patients with CP and CRC in relation to metabolic status.Materials and methods. The study included 12 patients with CRC (T2-4N0-2M0; mean age 59.6 ± 1.6 years) who were treated at the Department of Abdominal Oncology of the Cancer Research Institute of the Tomsk National Research Medical Center from 2019 to 2021. The comparison group included 10 patients with CP. The level of proteins on the surface of CD9- and FABP4-positive EVs was studied using flow cytometry.Results. MMP9-positive EVs were detected more often in CRC patients than in CP patients, however, MMP9+MMP2+TIMP-positive EVs were significantly more frequently detected in CP patients. Among the studied heat shock proteins, HSP60 was most often expressed on the surface of EVs, and HSP60-positive EVs were detected on the surface of CD9-positive exosomes in patients with PTC much more often than in CRC. In patients with CRC, compared with patients with СP, among FABP4-positive EVs, the proportion of triple-positive EVs and EVs with the MMP9+MMP2-TIMP1+ phenotype significantly increases, which in general may indicate overexpression of MMP9 and TIMP1 by adipocytes or marcrophages of adipose tissue in patients with CRC. Correlation analysis revealed multiple correlations of individual phenotypes of CD9-positive EVs in patients with CRC with body mass index and serum high density lipoprotein cholesterol levels, while the phenotypes of FABP4-positive EVs were associated mainly with triglyceride levels.Conclusions. The phenotypes of CD9-positive and FABP4-positive circulating EVs are promising as predictors for clarifying cancer risk in patients with colon polyps, as well as in terms of explaining the effectiveness of the treatment of CRC patients with obesity or metabolic syndrome.Введение. У большинства больных колоректальным раком (КРР) опухоль возникает на фоне метаболически здорового ожирения, или метаболического синдрома (более чем в 60 % случаев), ключевым патогенетическим моментом которого является развивающаяся гиперинсулинемия. метаболические изменения также характерны для больных с полипами толстой кишки (ПТК), которые в настоящее время рассматриваются как наиболее значимые предраковые заболевания. показано, что фракции малых внеклеточных везикул (ВВ) адипоцитарного происхождения специфически обогащены белками внеклеточного матрикса, включая матриксные металлопротеиназы (MMPs), шаперонами, а также некоторыми метаболическими ферментами, участвующими в синтезе липидов и углеводов. это послужило причиной выбора экзосомальных маркеров в нашем исследовании. Сравнение экспрессии протеинов на CD9-и FABP4-позитивных ВВ будет полезно для объяснения некоторых клинических моментов, например эффективности терморадиотерапии или радиотерапии у больных КРР с ожирением, а также для более обоснованного поиска везикулярных прогностических маркеров у онкологических пациентов с ожирением. цель исследования была сформулирована с учетом отсутствия в литературе данных об уровне экспрессии MMPs и белков теплового шока (HSPs) в составе тотального пула ВВ и в FABP4-позитивных ВВ у пациентов с ПТК и КРР.Цель исследования - изучение уровня MMPs и HSPs на CD9- и FABP4-позитивных ВВ у пациентов с ПТК и КРР во взаимосвязи с метаболическим статусом.Материалы и методы. В исследование были включены 12 больных КРР (T2-4N0-2M0; средний возраст 59,6 ± 1,6 года), проходивших лечение в отделении абдоминальной онкологии Научно-исследовательского института онкологии Томского национального исследовательского медицинского центра Российской академии наук с 2019 по 2021 г. В группу сравнения вошли 10 пациентов с ПТК. Уровень белков на поверхности CD9- и FABP4-позитивных ВВ был изучен с помощью проточной цитометрии.Результаты. ММР9-позитивные ВВ чаще выявлялись у больных КРР по сравнению с пациентами с ПТК, однако ММР9+ММР2+Т1МР-позитивные ВВ достоверно чаще обнаруживались у последних. Из изученных белков теплового шока на поверхности ВВ наиболее часто экспрессировался HSP60, причем HSP60-позитивные ВВ выявлялись на поверхности CD9-позитивных экзосом при ПТК гораздо чаще, чем при КРР. У больных КРР по сравнению с пациентами с ПТК среди FABP4-позитивных ВВ наблюдалось существенное увеличение доли трипл-позитивных ВВ и ВВ с фенотипом MMP9+MMP2-TIMP1+, что в целом может свидетельствовать о гиперэкспрессии MMP9 и TIMP1 адипоцитами или маркрофагами жировой ткани у больных КРР. Корреляционный анализ выявил множественные связи отдельных фенотипов CD9-позитивных ВВ у больных КРР с индексом массы тела и уровнем холестерина липопротеинов высокой плотности в сыворотке крови, в то время как фенотипы FABP4-позитивных ВВ были ассоциированы в основном с уровнем триглицеридов.Заключение. Фенотипы CD9-позитивных и FABP4-позитивных циркулирующих ВВ перспективны в качестве предикторов для уточнения онкологического риска у больных с полипами толстой кишки, а также в плане объяснения эффективности лечения больных КРР с ожирением или метаболическим синдромом