Analysis of the use of transosseous osteosynthesis in the treatment of patients with diabetic osteoarthropathy complicated by chronic osteomyelitis

Relevance Diabetic neuroosteoarthropathy (DNOAP) complicated by chronic osteomyelitis (CO) is one of the most common complications (up to 7.5 %) in patients with diabetes mellitus. Treatment failure of such patients leads to amputation of the segment, and in some cases, to death. The use of the method of transosseous osteosynthesis is the only alternative method in the struggle for the limb salvage. Purpose Based on X-ray morphological criteria for assessing bone quality, to determine the optimal assembly of the external fixation device (EFF), which provides favorable conditions for restoring limb weight-bearing capacity in the treatment of patients with DNOAP complicated by infection. Materials and methods The analysis of radiographs and the clinical course of the reparative process in 49 patients (mean age 55.5 ± 9.4 years) with DNOAP complicated by chronic osteomyelitis was carried out. Two groups were distinguished based on the Ilizarov apparatus assembly: wire-based (WB) used in 25 patients; hybrid construct (HC) in 24 patients. The X-ray obtained in Jpeg format were analyzed using specialized Hi-scene software. The density of the bones of the foot was studied by MSCT. Results Comparison of the indicators of bone optical density in both study groups showed that there was an insignificant increase in the postoperative period Od of the calcaneus by 25 % after treatment in patients from the HC group, and in the WB group by 43 % in the distal tibia. At the same time, we noted a significant increase in the Od values of the tibia in the postoperative period in patients from the HC group and in the body of the calcaneus in patients from the WB group. MSCT showed that the density of the calcaneus before treatment in patients with DNOAP in the region of the calcaneal tubercle was 194.37 ± 49.05 HU, in the region of the body it was 205.47 ± 38.36 HU, in the region of the distal tibia 280.00 ± 40.30 HU. The analysis of the results of bone osteosynthesis of the affected segment showed that the rate of satisfactory outcomes after dismantling the device in patients from the HC group was significantly higher than in the WB group (56 %) and amounted to 75 %. Discussion As is known, pronounced osteoporosis of the bones of the lower leg and foot is often characteristic of patients with diabetes mellitus complicated by DNOAP and chronic osteomyelitis. A possible arsenal of treatment methods that allow solving the problems of stable arrest of the osteomyelitic process and restoring limb support in such patients is very limited. The optimal choice of the Ilizarov apparatus assembly type has an impact on the outcome of treatment of patients with this pathology. Conclusion Based on X-ray morphological criteria for assessing bone quality, our study showed a decrease in optical and densitometric bone density in patients with DNOAP complicated by chronic osteomyelitis compared to the norm. The use of wire-based assembly of the apparatus does not provide sufficient conditions for the solution of the set of the surgical tasks in this category of patients. The introduction of half-pins into the apparatus system provides the necessary fixation time with the possibility of functional load on the operated segment in patients in the postoperative period

Mantle and Crustal Sources of Magmatic Activity of Klyuchevskoy and Surrounding Volcanoes in Kamchatka Inferred From Earthquake Tomography

Klyuchevskoy and surrounding volcanoes in central Kamchatka form the Northern Group of Volcanoes (NGV), which is an area of particularly diverse and intensive Pleistocene‐Holocene volcanism. In this study, we present a new seismic tomographic model of the crust and uppermost mantle beneath NGV based on local earthquake data recorded by several permanent and temporary seismic networks including a large‐scale experiment that was conducted in 2015–2016 by an international scientific consortium. Having an unprecedented resolution for this part of Kamchatka, the new model reveals many features associated with the present and past volcanic activity within the NGV. In the upper crust, we found several prominent high‐velocity anomalies interpreted as traces of large basaltic shield volcanoes, which were hidden by more recent volcanic structures and sediments. We interpret the mantle structure to reflect asthenospheric flow up through a slab window below the Kamchatka‐Aleutian junction that feeds the entire NGV. The interaction of the hot asthenospheric material with fluids released from the slab determines the particular volcanic activity within the NGV. We argue that the eastern branch of the Central Kamchatka Depression, which is associated with a prominent low‐velocity anomaly in the uppermost mantle, was formed as a recent rift zone separating the NGV from the Kamchatka Eastern Ranges.Key Points: We present a new high‐resolution seismic model of the crust and upper mantle beneath the Northern Group of Volcanoes in Kamchatka. The volcanoes of the Northern group are fed by an asthenosphere flow ascending from a slab window below the Kamchatka‐Aleutian junction. Eastern branch of the Central Kamchatka Depression is a rift separating the Northern Group of Volcanoes from the Eastern Ranges.Russian Ministry of Science and Education http://dx.doi.org/10.13039/501100012190Russian Science Foundation http://dx.doi.org/10.13039/100004111RFBR http://dx.doi.org/10.13039/501100002261European Union Horizon 2020 Research and Innovation Programme http://dx.doi.org/10.13039/50110001219

A new member of the cationic dinitrosyl iron complexes family incorporating N-ethylthiourea is effective against human HeLa and MCF-7 tumor cell lines

<p>A new analog of the active site of mononuclear dinitrosyl [1Fe–2S] proteins, [C₃N₂H₈SFe(NO)₂Cl][Fe(NO)₂(C₃N₂H₈S)₂]⁺Cl⁻ (<b>I</b>), has been synthesized by reacting NO with an aqueous mixture of iron(II) sulfate and N-ethylthiourea in acidic medium. The structure and properties of the complex were studied by X-ray diffraction, IR, Mössbauer, and EPR spectroscopy, in addition to quantum chemical calculations. Complex <b>I</b> spontaneously generates NO in protic media. The cytotoxicity of <b>I</b> was investigated against human cervical carcinoma (HeLa), breast cancer (MCF7), and non-immortalized (FetMCS) cell lines. The cytotoxicity of <b>I</b> against HeLa is similar to that of anticancer agents currently used clinically (platinum complexes), but <b>I</b> is 10 times less toxic in normal cells. The cytotoxicity of MCF7 cells to <b>I</b> is low.</p