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The adhesion strength of the solid phase boundary in the Ge20Se80 glass–substrate (quartz glass, stainless steel, tungsten carbide) systems was measured using the normal separation method in the temperature range of 270 – 360°C. The maximum work of adhesion of chalcogenide glass among the studied structural materials was observed for stainless steel with a non-nitrided surface. The wetting and adhesion of the Ge20Se80 glass melt to structural materials in the temperature range of 370 – 470°C were investigated. The maximum adhesion of the chalcogenide melt is observed for the surface of quartz glass, while the minimum is observed for the surface of nitrided stainless steel. [ABSTRACT FROM AUTHOR]

A computational fluid dynamics model of the glass fiber extrusion process is proposed and verified. The model describes the homogeneous non‐isothermal motion of a viscous glass melt and the surrounding air in an experimental setup, taking into account the interface between the media and the movement of the metal rod. The unclad Ge28Sb12Se60 glass fibers for sensor applications are fabricated by extrusion. The validation of the developed model is performed based on the experimental data, including pressure values, temperature field in extrusion setup, and extruded glass mass outflow. Based on the proposed model, the thermal and kinetic conditions for the flow of Ge28Sb12Se60 glass during extrusion are numerically studied. The presented model could be used as a tool for analyzing the hydrodynamic and thermal processes during fiber extrusion. [ABSTRACT FROM AUTHOR]

Using normal pull-off testing, we have studied adhesion contact strength in the GaxGe40–xS60–quartz glass system as a function of contact formation temperature, pull-off test temperature, and chalcogenide glass composition. The addition of 1 at % gallium to glass composition considerably reduces the adhesion strength. Further increasing the percentage of gallium, to 8 at %, causes only a slight drop in adhesion. The observed general relationships can be accounted for by partial glass crystallization on heating for adhesion contact formation and subsequent cooling to the pull-off test temperature. We have formulated recommendations concerning detachment of GaxGe40–xS60 glasses from the quartz reactor wall. [ABSTRACT FROM AUTHOR]

This work compares the metabolic profiles of plasma and the cerebrospinal fluid (CSF) of the patients with high-grade (III and IV) gliomas and the conditionally healthy controls using the wide-range targeted screening of low molecular metabolites by HPLC-MS/MS. The obtained data were analyzed using robust linear regression with Huber's M-estimates, and a number of metabolites with correlated content in plasma and CSF was identified. The statistical analysis shows a significant correlation of metabolite content in plasma and CSF samples for the majority of metabolites. Several metabolites were shown to have high correlation in the control samples, but not in the glioma patients. This can be due to the specific metabolic processes in the glioma patients or to the damaged integrity of blood-brain barrier. The results of our study may be useful for the understanding of molecular mechanisms underlying the development of gliomas, as well as for the search of potential biomarkers for the minimally invasive diagnostic procedures of gliomas.

The aim of the study was to evaluate the efficacy of a novel technique for preparation, staining, and visualization of tissues containing extra-skeletal mineralization areas, all-metal implants or their prototypes for their subsequent examination using scanning electron microscopy in the backscattered electron mode., Materials and Methods: After fixation in 10% formalin (24 h), the biomaterial (a titanium nickelide plate with the surrounding tissues after subcutaneous implantation, patented titanium alloy plates with the surrounding tissues after cranioplasty, primary and secondary calcified atherosclerotic plaques) were fixed with 1% osmium tetroxide (12 h) and then stained with 2% aqueous solution of osmium tetroxide (48 h). The samples were further stained with 2% alcoholic uranyl acetate (5 h), dehydrated with isopropanol (5 h) and acetone (1 h), impregnated with a mixture of acetone and epoxy resin Epon (1:1, 6 h) and then embedded into a fresh portion of epoxy resin (24 h), which was followed by polymerization at 60°C. After grinding and polishing, epoxy blocks were counterstained with lead citrate (7 min) and sputter-coated with carbon, then the samples were visualized by scanning electron microscopy in the backscattered electron mode. The elemental composition was studied using X-ray microanalysis., Results: The developed technique allows obtaining high-quality images at five thousand-fold magnifications, provides the possibility to identify the shape and structure of intact metal and mineral inclusions, and to type the surrounding cells, distinguishing mesenchymal and immunocompetent cells by shape and cytoplasmic content. Apart from connective tissue capsule thickness and leukocyte infiltration, this technique makes it possible to estimate the number and area of newly formed small-caliber vessels representing a surrogate marker of inflammation., Conclusion: The proposed technique provides the possibility to investigate adequately the structure of samples when their sectioning is impossible or significantly complicated, with image quality remarkably higher than that obtained by light microscopy., Competing Interests: Conflict of interests. The authors have no conflict of interests to disclose.

Although major progress has been made in the standard treatment for glioblastomas, encompassing the maximal surgical resection, chemotherapy and radiation therapy, it is possible to increase survival rates significantly only in a few patients. Therefore, it is necessary to explore new therapeutic modalities, one of which is immunotherapy. The aim of the study was to evaluate the efficacy of the combined use of autologous and pooled tumor lysates in comprehensive treatment of patients with glioblastoma., Materials and Methods: All patients (n=58, including 30 males and 28 females aged 18-70 years) were randomized into three groups, two of which received immunotherapy based on injection of autologous dendritic cells pulsed with autologous tumor lysates (first protocol) or pooled lysates (second protocol) from more than one tumor, in addition to the planned standard treatment. The patients of group 3 (control) received the standard comprehensive treatment encompassing the maximum safe tumor resection followed by radiation therapy and chemotherapy., Results: The tolerability of both applied immunotherapy protocols was good: there were no anaphylactic reactions observed or patients who prematurely discontinued participation in the study. The final analysis of the data revealed no significant differences in median survival values of patients in each of the three groups. However, when analyzing the Karnofsky Performance Status in patients of group 2, it was found that it tended to improve., Conclusion: The study shows that the proposed immunotherapy protocols are safe for clinical use and have the potential to improve the patient's life quality. However, these findings should be considered intermediate until the findings of multicenter randomized clinical trials with a larger number of patients are obtained., Competing Interests: Conflict of interests. The authors have no conflict of interests to disclose.

We report a clinical case of cerebral actinomycotic granuloma that was preoperatively diagnosed as an intracerebral tumor. On the basis of a histological examination performed after lesion resection, the diagnosis of a cerebral actinomycotic granuloma was made. The article presents long-term outcomes of the surgery. The literature data on cases of various forms of cerebral actinomycosis are provided.