Novel wearable VCSEL-based blood perfusion sensor

A wearable 850 nm VCSEL-based blood perfusion sensor operating on the principles of laser Doppler flowmetry (LDF) and Dynamic Light Scattering (DLS) has been developed and tested. The sensitivity of the sensor to changes in skin blood perfusion has been demonstrated

New trophic classification of wood-destroying fungi the case of community of pathogenic polypore fungi types on Pedunculate oak

Based on the generalization of experimental data obtained during the practical study of the trophic specialization of wood-destroying fungi from the commonness of PTH on oak in the oak forests of the south-west of the Central Russian Upland, a new ecotrophic classification has been developed, including the following groups of wood-destroying fungi: biotrophic pathogens, saprotrophic pathogens, pathogenic saprotrophs, non-pathogenic saprotroph

Opportunities for the analysis of the spatial ecological structure of the mycobiota of macromycetes of a natural-territorial entity (the case of the Botanical Garden of Belgorod University, Belgorod, Russia)

On the basis of direct observations, the general principles of the organization of the mycobiota of the macromycetes of the natural-territorial formation "Botanical Garden" of Belgorod State University (Belgorod, Russian Federation) have been clarified. Based on the clarified principles, a scheme of their spatial ecological organization has been constructed: mycobiota - mycohore (mycocenosis, mycoaggregation) - mycosinium-3 - mycocenocells - mycocell. The obtained results can be used to study the spatial ecological organization of mycobiota macromycetes of other natural-territorial formation

Trans-species relation in communities of pathogenic Polyporaceae on pedunculate oak Quercus robur L

In the process of research phytopathological and mycocenological methods were used As a result of the research, real trans-species relation were revealed in the most common and frequently occurring types of PPF on oak within various communities: Mutually positive type relationships based on the proto-operation were found between Laetiporus sulphureus and Fistulina hepatica. Neutral type relationships were found in between Fistulina hepatica and Fomitiporia robusta, Laetiporus sulphureus and Fomitiporia robust

The mechanisms of sensitization of gastrointestinal stromal tumor cells to DNA topoisomerase II inhibitors

Aim. To examine the ability of receptor tyrosine kinase inhibitors to modulate gastrointestinal stromal tumor cells sensitivity to DNA topoisomerase II inhibitors. Methods. The following receptor tyrosine kinase inhibitors were used in the present study - imatinib, crizotinib, cabozantinib and sunitinib. An ability of the named medications to sensitize gastrointestinal stromal tumor cells to DNA topoisomerase II inhibitor (doxorubicin) was examined by using an MTS-based colorimetric assay. The expression of apoptotic, DNA damage and repair markers was assessed with western blotting by using the corresponding monoclonal antibodies. Proliferative activity was examined in a real-time by utilizing an iCELLigence system (ACEA Biosciences Inc., USA). Results. We found that all above-mentioned receptor tyrosine kinase inhibitors were able to sensitize gastrointestinal stromal tumor cells to topoisomerase II inhibitors. This leads to the decrease of proliferative activity of tumors cells and enhancement of apoptotic cell death. Importantly, this effect was observed in imatinib-resistant gastrointestinal stromal tumor cells. One of the possible molecular mechanisms responsible for sensitization of these cells to topoisomerase II inhibitors was the ability of the target medications to inhibit the homologous recombination. This is evidenced by substantial decrease of Rad51 recombinase expression as a result of receptor tyrosine kinase inhibitor effect on the cells with DNA damage caused by topoisomerase II inhibitors. Conclusion. Receptor tyrosine kinase inhibitors are able to sensitize imatinib-resistant gastrointestinal stromal tumor cells to topoisomerase II inhibitors by inhibiting DNA homologous recombination

The influence of local pressure on evaluation parameters of skin blood perfusion and fluorescence

This article presents the results of the study of the pressure applied on optical diagnostic probes as a significant factor affecting the results of measurements. During stepwise increasing and decreasing of local pressure on skin we conducted measurements using the methods of laser Doppler flowmetry and fluorescence spectroscopy. It was found out that pressure on optical probe has sufficient impact on skin microcirculation to affect registered fluorescence intensity. Data obtained in this study are of interest for design and development of diagnostic technologies for wearable devices. This data will also inform further investigation into issues of compensation of blood absorption influence on fluorescence spectrum, allowing increased accuracy and reproducibility of measurements by fluorescence spectroscopy methods in optical diagnosis

A novel receptor tyrosine kinase switch promotes gastrointestinal stromal tumor drug resistance

© 2017 by the authors. The fact that most gastrointestinal stromal tumors (GISTs) acquire resistance to imatinib (IM)-based targeted therapy remains the main driving force to identify novel molecular targets that are capable to increase GISTs sensitivity to the current therapeutic regimens. Secondary resistance to IM in GISTs typically occurs due to several mechanisms that include hemi- or homo-zygous deletion of the wild-type KIT allele, overexpression of focal adhesion kinase (FAK) and insulin-like growth factor receptor I (IGF-1R) amplification, BRAF mutation, a RTK switch (loss of c-KIT and gain of c-MET/AXL), etc. We established and characterized the IM-resistant GIST T-1 cell line (GIST T-1R) lacking secondary c-KIT mutations typical for the IM-resistant phenotype. The resistance to IM in GIST T-1R cells was due to RTK switch (loss of c-KIT/gain of FGFR2α). Indeed, we have found that FGFR inhibition reduced cellular viability, induced apoptosis and affected the growth kinetics of the IM-resistant GISTs in vitro. In contrast, IM-naive GIST T-1 parental cells were not susceptible to FGFR inhibition. Importantly, inhibition of FGF-signaling restored the susceptibility to IM in IM-resistant GISTs. Additionally, IM-resistant GISTs were less susceptible to certain chemotherapeutic agents as compared to parental IM-sensitive GIST cells. The chemoresistance in GIST T-1R cells is not due to overexpression of ABC-related transporter proteins and might be the result of upregulation of DNA damage signaling and repair (DDR) genes involved in DNA double-strand break (DSB) repair pathways (e.g., XRCC3, Rad51, etc.). Taken together, the established GIST T-1R cell subline might be used for in vitro and in vivo studies to examine the efficacy and prospective use of FGFR inhibitors for patients with IM-resistant, un-resectable and metastatic forms of GISTs with the type of RTK switch indicated above

Optimization of preoperative planning and intraoperative navigation at the shoulder replacement

There were 105 patients with shoulder replacement under our supervision (terms of supervision were up to 10 years). There were 43 men and 62 women. Age of patients was from 29 to 80 years. Two ways of optimization of shoulder replacement are offered: "Method of preoperative determination of the sizes of a head of shoulder joint endoprosthesis" (Patent of the Russian Federation N 2469670 d.d. 12.20.2012) and "Method for intraoperative navigation of a shoulder stem of joint" (Patent of the Russian Federation N 2467725 d.d. 11.27.2012). We reached the improvement of quality of the operation due to the fact of an installation of the implants which are as much as possible close to the anatomy of a normal shoulder joint by size and position

The development of attenuation compensation models of fluorescence spectroscopy signals

This study examines the effect of blood absorption on the endogenous fluorescence signal intensity of biological tissues. Experimental studies were conducted to identify these effects. To register the fluorescence intensity, the fluorescence spectroscopy method was employed. The intensity of the blood flow was measured by laser Doppler flowmetry. We proposed one possible implementation of the Monte Carlo method for the theoretical analysis of the effect of blood on the fluorescence signals. The simulation is constructed as a four-layer skin optical model based on the known optical parameters of the skin with different levels of blood supply. With the help of the simulation, we demonstrate how the level of blood supply can affect the appearance of the fluorescence spectra. In addition, to describe the properties of biological tissue, which may affect the fluorescence spectra, we turned to the method of diffuse reflectance spectroscopy (DRS). Using the spectral data provided by the DRS, the tissue attenuation effect can be extracted and used to correct the fluorescence spectra

Study of Molecular and Ionic Vapor Composition over CeI3 by Knudsen Effusion Mass Spectrometry

The molecular and ionic composition of vapor over cerium triiodide was studied by Knudsen effusion mass spectrometry. In the saturated vapor over CeI3 the monomer, dimer, and trimer molecules and the negative ions I−, CeI4−, and Ce2I7− were identified in the temperature range of 753–994 K. The partial pressures of CeI3, Ce2 I6, and Ce3I9 were determined and the enthalpies of sublimation, Δ