Differential diagnosis of the disease of the great Russian artist I. Repin

The year 2024 marks the 180th anniversary of the birth of the great artist Ilya Efimovich Repin, the brightest representative of the realist direction of academic art. The artist’s life was overshadowed by a disease that deprived him of the ability to work with his right hand. I.E. Repin, with an irresistible will to create, re-trained to paint with his left hand. Repin’s disease was not diagnosed both during his life and after his death. This article contains information about Ilya Repin’s disease and differential diagnosis with pathology, which can be followed by motor disorders of the hand and atrophy of the hand muscles. The conducted analysis, supported by literature and lifetime photographs, postmortem cast of the artist’s right hand indicate that the cause of Repin’s disease was a progressive ulnar neuropathy. The given historical information about the diseases of peripheral nerves indicates that this diagnosis could not have been established during the artist’s lifetime

The Dzerzhinka Section (eastern slope of the South Urals): An overview of the fauna and facies around the Devonian-Carboniferous boundary

TheDevonian-Carboniferous boundary section near the village of Dzerzhinka (vicinity ofVerkhneuralsk) on the Ural River on the eastern slope of the South Urals, Russia, contains a wide variety of fossil invertebrates, including foraminifers, ostracodes, ammonoids, conodonts, and brachiopods. Diverse Upper Famennian assemblages are associated with wackestone-grainstone microfacies and bioclastic-volcaniclastic arenite, suggesting normal marine sedimentation in a volcanic-arc setting. The presence of well-established shallow-water benthic communities associated with the basinal Palmatolepis conodont biofacies and breccias is difficult to interpret. The latest Devonian and earliest Mississippian Siphonodella praesulcata and S. sulcata conodont zones are missing from the succession, indicating a discontinuity of sedimentation that is, associated with a hardground with phosphorite nodules. By the time of the S. quadruplicata Zone, normal marine sedimentation resumed, while the shelf continued to subside and was eventually overlain by siliciclastic and cherty sediments

Искусственный нервный проводник для направленного роста периферических нервов (кадаверное исследование)

At present, the search for effective ways of restoring peripheral nerves with anatomical damage continues. Autoplasty still remains the gold standard, which, however, is not without its drawbacks. The use of nerve implants for promoting directional axon growth is essential and promising.Objective: to study the biomechanical properties of laboratory samples of an artificial nerve conduit (NGC) made of hybrid biomaterials and to, on cadaveric material, assess the technical feasibility of using them in surgical practice to repair extended peripheral nerve defects.Material and methods. The objects of the study were three electrospun NGC samples: from synthetic material (polycaprolactone, PCL) and hybrid biomaterials (PCL + gelatin or PCL + collagen). The work compared the physical and mechanical properties of NGC: stiffness, plasticity, elasticity, brittleness, resistance to chemical attack, their ability to be impregnated with liquid media, permeability, possibility of making an anastomosis between the implant and the nerve during surgical procedure. Cadaveric material was the object of the study: we used a dissected superficial sensory branch of the human right radial nerve, 2 mm in diameter, isolated on the forearm, about 12 cm in length, because it most corresponded to the diameter of the NGC samples tested. After surgery, the echogenic features of the implants and their anastomoses with the nerve were assessed by ultrasound imaging.Results. It was found that hybrid NGC samples, based on their biomechanical properties, are fundamentally suitable for use in surgical practice, to ensure growth and replacement of a peripheral nerve defect. However, the best composition of a nerve guide can be established after comparative preclinical study of the biocompatible and functional properties of hybrid material samples.Conclusion. The physical and mechanical properties of the investigated NGC samples made of hybrid biomaterials meet the technical requirements for implantable nerve conduits for surgical application.В настоящее время продолжаются поиски эффективных способов восстановления периферических нервов при анатомическом нарушении их целостности. Золотым стандартом по-прежнему остается аутопластика, которая, однако, не лишена недостатков. Актуальным и перспективным является метод применения нервных имплантатов для направленного роста аксонов.Цель: изучить биомеханические свойства лабораторных образцов искусственного нервного проводника (ИНП) – нервного кондуита, изготовленных из гибридных биоматериалов, и на кадаверном материале оценить техническую возможность их применения в хирургической практике для восстановления протяженных дефектов периферических нервов.Материал и методы. Объектами исследования служили изготовленные методом электроспиннинга три образца ИНП: из синтетического материала – поликапролактона (ПКЛ) и гибридных биоматериалов (ПКЛ с желатином или коллагеном). В ходе работы сравнивались физические и механические свойства ИНП: жесткость, пластичность, эластичность, хрупкость, устойчивость образцов к химическому воздействию, их способность к пропитыванию жидкими средами, проницаемость, возможность наложения анастомоза между имплантатом и нервом во время хирургической операции. В качестве кадаверного материала использовали поверхностную чувствительную ветвь правого лучевого нерва человека диаметром 2 мм, выделенную на предплечье протяженностью около 12 см, как наиболее соответствующую диаметру тестируемых образцов ИНП. После хирургической операции оценивали эхогенные признаки имплантатов и их анастомозов с нервом методом ультразвуковой визуализации.Результаты. Установлено, что образцы ИНП из гибридных материалов по биомеханическим свойствам принципиально пригодны для использования в хирургической практике для обеспечения роста и замещения дефекта периферических нервов. Однако наилучший состав нервного проводника может быть установлен после проведения сравнительных доклинических исследований биосовместимых и функциональных свойств образцов из гибридных материалов.Заключение. Физические и механические свойства исследуемых образцов ИНП из гибридных биоматериалов соответствуют техническим требованиям, предъявляемым к имплантируемым нервным проводникам при их хирургическом применении

Role of Inflammatory Mediators, Growth Factors, and Osteodystrophy in Recurrent Lumbar Disk Herniation

Introduction. Reintervention in patients with spinal disk herniation is shown to significantly decrease likelihood of favorable outcomes in the postoperative period. Thus, it is important to individually assess risk factors for and likelihood of spinal disk herniation recurrence for each patient, and choose a suitable surgical option. Objective: to evaluate changes in the levels of immunoregulatory mediators in the blood serum and extracted spinal disc tissue of allegedly healthy individuals and patients with lumbar disk herniation relapses. Materials and methods. We examined 60 patients. The control group included 19 patients with traumatic spinal cord injuries at the lumbar level. The main group included 41 patients with spinal disk herniation. Twenty-two individuals had primary herniation while 11 patients presented with single clinical and neurological relapses at the pre-operated lumbar level and 8 patients presented with recurrent relapses. Solid-phase enzyme immunoassay detected proinflammatory cytokines (interleukin-6, tumor necrosis factor-), chemokines (interleukin-8, monocyte chemoattractant protein-1), growth factors (vascular endothelial growth factor, transforming growth factor-1), and osteodestruction markers (osteoprogesterin, matrix metalloproteinase-8) in the blood serum and the extracted spinal disc tissue. Results. We found that spinal disk destruction and chronic inflammation developed with both locally and generally elevating levels of proinflammatory cytokines/chemokines, growth factors, and matrix metalloproteinase 8. Conclusion. The results emphasize the significance of local changes in the studied parameters to choose and plan personalized surgical treatment in patients with spinal disk herniation

Artificial nerve conduit for guiding peripheral nerve growth (cadaveric study)

At present, the search for effective ways of restoring peripheral nerves with anatomical damage continues. Autoplasty still remains the gold standard, which, however, is not without its drawbacks. The use of nerve implants for promoting directional axon growth is essential and promising.Objective: to study the biomechanical properties of laboratory samples of an artificial nerve conduit (NGC) made of hybrid biomaterials and to, on cadaveric material, assess the technical feasibility of using them in surgical practice to repair extended peripheral nerve defects.Material and methods. The objects of the study were three electrospun NGC samples: from synthetic material (polycaprolactone, PCL) and hybrid biomaterials (PCL + gelatin or PCL + collagen). The work compared the physical and mechanical properties of NGC: stiffness, plasticity, elasticity, brittleness, resistance to chemical attack, their ability to be impregnated with liquid media, permeability, possibility of making an anastomosis between the implant and the nerve during surgical procedure. Cadaveric material was the object of the study: we used a dissected superficial sensory branch of the human right radial nerve, 2 mm in diameter, isolated on the forearm, about 12 cm in length, because it most corresponded to the diameter of the NGC samples tested. After surgery, the echogenic features of the implants and their anastomoses with the nerve were assessed by ultrasound imaging.Results. It was found that hybrid NGC samples, based on their biomechanical properties, are fundamentally suitable for use in surgical practice, to ensure growth and replacement of a peripheral nerve defect. However, the best composition of a nerve guide can be established after comparative preclinical study of the biocompatible and functional properties of hybrid material samples.Conclusion. The physical and mechanical properties of the investigated NGC samples made of hybrid biomaterials meet the technical requirements for implantable nerve conduits for surgical application

ПАЛЕОТЕКТОНИЧЕСКИЕ И ПАЛЕОГЕОГРАФИЧЕСКИЕ ОБСТАНОВКИ НАКОПЛЕНИЯ НИЖНЕРИФЕЙСКОЙ АЙСКОЙ СВИТЫ БАШКИРСКОГО ПОДНЯТИЯ (ЮЖНЫЙ УРАЛ) НА ОСНОВЕ ИЗУЧЕНИЯ ДЕТРИТОВЫХ ЦИРКОНОВ МЕТОДОМ «TERRANECHRONE®»

The TerraneChrone® (LA-ICP-MS) technique has been applied to carry out an integrated study of detrital zircons in sandstones sampled from the basal horizons of the stratotypical Riphean sequence in the Southern Urals, specifically the Navysh and Chudin suites of the Ai Formation of the Burzyan Group in the Bashkir Uplift. The concentrations of trace elements in the detrital zircons suggest that the role of oceanic or marginal-marine complexes among the primary sources of zircons was insignificant, and show a better agreement with the intra-continental rather than passive-margin origin of the Riphean basin, whose basal levels are composed by the Ai Formation. The U/Pb ages of zircons from samples K13-206 and M08-16-1 are generally similar: the Paleoproterozoic zircons predominate (the dominant peaks are actually coincident, 2063 and 2055 Ma), and only a few grains of the Archean age are present. Despite the similar U/Pb ages of the detrital zircons, these two samples considerably differ in their Hf isotopic features and the concentrations of trace elements, which means that the zircons in the studied sandstones are of different geodynamic origin. The characteristics of these zircons can be explained by a model showing the Ai Formation in the Navysh graben that is a rift structure and a predecessor of the Kama-Belaya aulacogene in the inner Volga-Ural region of the Paleoproterozoic supercontinent Columbia. At the initial stage of rifting, the granitoid complexes with a lower total silicic acidity, which composed the graben walls, had been eroded; as a result of erosion, coarse clastic rocks accumulated within the Navysh graben and formed the Navysh suite. A specific “carbonatitic” complex containing zircons (about 2.0, 2.5, 2.85 and 3.6 Ga) and the Palaeoarchean crustal material in the substrate of their parent rocks was also eroded. In the final stage of rifting, already at the initial stages of the development of the Kama-Belaya aulacogen (Chudin suite), the erosion products from the paleo-aquifers occupying vast areas began to be transported into the rift. The primary sources of clastics for the Chudin suite were both granitoids of the lower and normal silicic acidity. Besides, a specific “carbonatitic” complex containing juvenile zircons (about 2.05 Ga) was eroded. However, by that time, significant areas of the Archaean basement of the Volga-Ural region might have become hidden underneath a proto-cover and thus not eroded, so the Archean detritus in the Chudin suite is poorly represented in comparison with the Navysh suite, considering both the amounts and ages of detrital zircons. As of today, the Precambrian carbonatite rocks within both the Taratash complex (composing the basement of the Navysh graben) and the southeastern segment of the East-European Platform have not yet been described. The source of the “carbonatite” zircons remains unknown and can be discovered as more and more data on the basement rocks is accumulated. В статье представлены результаты комплексного изучения по методике «TerraneChrone®» (LA-ICP-MS) детритных цирконов, выделенных из песчаников, слагающих базальные горизонты (навышская и чудинская подсвиты айской свиты бурзянской серии Башкирского поднятия) стратотипического разреза рифея на Южном Урале. Зафиксированные в цирконах содержания элементов-примесей свидетельствуют о малой роли комплексов океанического или окраинно-морского генезиса среди первичных источников цирконов и лучше согласуются с внутриконтинентальным, а не окраинно-континентальным расположением рифейского бассейна, базальные уровни которого выполнены айской свитой. U/Pb возрастные характеристики изученных цирконов в обеих пробах в общем схожи: преобладают палеопротерозойские цирконы (доминирующие пики фактически совпали – 2063 и 2055 млн лет), а архей представлен только немногочисленными зернами. При схожести U/Pb возрастных параметров детритных цирконов по Hf-изотопным признакам этих цирконов и содержаниям в них элементов-примесей зафиксированы существенные различия между пробами, свидетельствующие о том, что источниками цирконов для изученных песчаников были различные по геодинамической природе комплексы. Особенности характеристик цирконов в изученных пробах могут быть объяснены в рамках модели формирования айской свиты в рифтовой структуре – Навышском грабене – предшественнике Камско-Бельского авлакогена во внутренней волго-уральской части палеопротерозойского суперконтинента Колумбия. На начальной стадии рифтогенеза в Навышском грабене накапливались грубообломочные породы (навышская подсвита), представляющие собой продукты размыва слагающих борта этого грабена гранитоидных комплексов пониженной валовой кремнекислотности. В размыв попал также комплекс, содержащий специфические «карбонатитовые» цирконы с возрастом около 2.0, 2.5, 2.85 и 3.6 млрд лет и с участием палеоархейского корового материала в субстрате материнских по отношению к ним пород. В завершающую стадию рифтогенеза, уже на начальных стадиях развития Камско-Бельского авлакогена (чудинская подсвита), в грабен стали попадать эрозионные продукты с палеоводосборов, занимающих более обширные площади, первичными источниками кластики для которых были гранитоиды как пониженной, так и нормальной кремнекислотности. В размыв попал также комплекс, содержащий специфические ювенильные «карбонатитовые» цирконы с возрастом около 2.05 млрд лет. Однако к этому времени значительные площади архейского фундамента Волго-Уралии, вероятно, были покрыты проточехлом и не дренировались, поэтому архейский детрит в навышской подсвите представлен скуднее по сравнению с чудинской подсвитой и по количеству, и по возрастным группам. До сих пор докембрийские карбонатитовые породы ни в тараташском комплексе, слагающем фундамент Навышского грабена, ни в юго-восточной части Восточно-Европейской платформы не описаны, и вопрос об источнике этих «карбонатитовых» цирконов остается открытым, но имеет перспективу быть решенным по мере накопления данных о фундаменте

LITHOFACIAL FEATURES OF THE UPPER DEVONIAN SEDIMENTS IN THE MENDYM SECTION (INZER-USOLSKY TROUGH, SOUTHERN URALS)

The article considers the lithofacial features of Upper Devonian carbonate rocks in the Mendym section, in rock outcrops along the right and left banks of the Mendym River flowing through the Mendym settlement. Five lithofacies were identified in the rocks: micro-grained wackstones with ammonoids, crinoid-brachiopod coquina — rudstones-grainstones at the upper part of the Frasnian; lumpy-breccia-like wackstones with ammonoids, bioturbated wackstones with calcispheres and peloid-clumped packstones with foraminifera in the Famennian. The complex of lithofacial features indicates the conditions of the deep-sea shelf of the ramp type with the influence of storms.</jats:p