Репозиторий Университета

© 2019 Elsevier B.V. In the present study, porous three-dimensional (3D) printed titanium (Ti) implants of complex shape and predefined architecture were produced by selective laser sintering (SLS) technique. Electrochemical deposition combined with biomimetic approach was applied to low-temperature coating of these implants with metastable octacalcium phosphate (OCP) achieved via chemical transformation of dicalcium phosphate dehydrate (DCPD). X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and compressive strength analyses were applied to study the chemical composition, morphology and mechanical properties of the final OCP coating on the titanium surface. In vivo comparative study of the porous 3D printed Ti and OCP coated Ti implants has been performed using critical-size crania model, porous 3D printed Ti and coated implants were compared. A statistically significant difference in the newly formed bone thickness for OCP coated Ti implants was detected already at 6 weeks after implantation. Our results provide an experimental proof of a new concept of OCP coating for cranioplasty clinical applications.

© 2019 Elsevier B.V. The results of the study of composites based on bovine serum albumin (BSA) and single-walled carbon nanotubes (SWCNT) are presented. Nanocomposites were created by evaporation of the water-albumin dispersion with nanotubes using diode laser with temperature control. Two types of nanotubes were used. SWCNT I were synthesized using the electric arc method, SWCNT II were synthesized using the gas phase method. SWCNT I had a diameter and length less than SWCNT II. The mechanism of interaction between BSA and SWCNT in solid nanocomposites is considered. An experimental and theoretical studies of the interaction between aspartic (Asp) and glutamic (Glu) amino acids located on the outer surface of BSA and nanotubes using of vibrational spectroscopy (Fourier-transform infrared (FTIR) and Raman spectroscopy) was carried out. The possibility of nanotubes functionalization by oxygen atoms of negative amino acid residues Asp and Glu, which are on the outer surface of BSA, is shown by molecular modeling. The formation of covalent bonds between BSA and SWCNT in nanocomposites with different concentrations of nanotubes (0.01, 0.1 and 1 g/l) was confirmed by vibrational spectra. The covalent interaction between BSA with SWCNT under the laser irradiation leads to the conformational changes in the secondary and tertiary structures of albumin. This is confirmed by a significant decrease in the intensity of the absorption bands in the high-frequency region. The calculation of the vibrational spectra of the three Glycine:Glycine, Glutamic acid:Threonine and Aspartic acid:Lysine complexes, which take into account hydrogen, ion-dipole and ion-ion bonds, showed that a disturbance in the intermolecular interaction between amino acid residues led to significant decrease in the intensity of absorption bands in the region of stretching vibrations bonds OH and NH. From the Raman spectra, it was found that a significant number of defects in SWCNT is caused by the covalent attachment of oxygen atoms to the graphene surface of nanotubes. An increase in the diameter of nanotubes (4 nm) has practically no effect on the absorption spectrum of nanocomposite, while measuring the concentration of SWCNT affects the FTIR spectra. This confirmed the hydrophobic interaction between BSA and SWCNT. Thus, it was shown that BSA solid nanocomposites with CNTs can interact either with the help of hydrophobic forces or with the formation of covalent bonds, which depends on the diameter of the used nanotubes. The viability of connective fibroblast tissue cells on nanocomposites with both types of SWCNT was demonstrated. It was found that nanocomposites based on SWCNT I provide slightly better compatibility of their structure with fibroblasts. It allows to achieve better cell adhesion to the nanocomposite surface. These criteria make extensive use of scaffold nanocomposites in biomedicine, depending on the requirements for their quality and application.

© 2018 The Authors Radionuclide-based imaging of molecular therapeutic targets might facilitate stratifying patients for specific biotherapeutics. New type of imaging probes, based on designed ankyrin repeat proteins (DARPins), have demonstrated excellent contrast of imaging of human epidermal growth factor type 2 (HER2) expression in preclinical models. We hypothesized that labeling approaches, which result in lipophilic radiometabolites (non-residualizing labels), would provide the best imaging contrast for DARPins that internalize slowly after binding to cancer cells. The hypothesis was tested using DARPin Ec1 that binds to epithelial cell adhesion molecule (EpCAM). EpCAM is a promising therapeutic target. Ec1 was labeled with 125I using two methods to obtain the non-residualizing labels, while residualizing labels were obtained by labeling it with 99mTc. All labeled Ec1 variants preserved target specificity and picomolar binding affinity to EpCAM-expressing pancreatic adenocarcinoma BxPC-3 cells. In murine models, all the variants provided similar tumor uptake. However, 125I-PIB-H6-Ec1 had noticeably lower retention in normal tissues, which provided appreciably higher tumor-to-organ ratios. Furthermore, 125I-PIB-H6-Ec1 demonstrated the highest imaging contrast in preclinical models than any other EpCAM-imaging agent tested so far. In conclusion, DARPin Ec1 in combination with a non-residualizing label is a promising probe for imaging EpCAM expression a few hours after injection.

© 2019 Elsevier B.V. In the present study, porous three-dimensional (3D) printed titanium (Ti) implants of complex shape and predefined architecture were produced by selective laser sintering (SLS) technique. Electrochemical deposition combined with biomimetic approach was applied to low-temperature coating of these implants with metastable octacalcium phosphate (OCP) achieved via chemical transformation of dicalcium phosphate dehydrate (DCPD). X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and compressive strength analyses were applied to study the chemical composition, morphology and mechanical properties of the final OCP coating on the titanium surface. In vivo comparative study of the porous 3D printed Ti and OCP coated Ti implants has been performed using critical-size crania model, porous 3D printed Ti and coated implants were compared. A statistically significant difference in the newly formed bone thickness for OCP coated Ti implants was detected already at 6 weeks after implantation. Our results provide an experimental proof of a new concept of OCP coating for cranioplasty clinical applications.

© 2019 Elsevier B.V. Background: Isolated brain of experimental animals is a useful model to study transport of substances, including drugs, across the blood-brain barrier, mechanisms of convulsive activity, ischemic and reperfusion brain injury. Normal functioning of neurons, especially cortical, in the central nervous system requires adequate supply of oxygen. Therefore oxygen carriers or fluorocarbon substances with high oxygen capacity are often used in animal brain perfusion experiments. New method: In the present study of the in situ rat brain perfusion oxygen carriers were not used. The optimum oxygen capacity of the perfusion media (adequate to the arterio-venous difference) was achieved by a high oxygen tension (2400−2600 mm Hg) in the solution under normal barometric pressure. Perfusate was depressurized and delivered at normal rat systemic hydrostatic pressure to the brain via a cannula inserted transcardially into the ascending aorta, with both subclavian arteries ligated. Perfusate was delivered using normal hydrostatic pressure. Results: In these experimental conditions of the brain perfusion the pattern of electrocorticogram has been stable in the course of 5 h and more. The release of lactic acid in the perfusion solution was 3 times less than in perfusion under partial oxygen tension of 900 mm Hg; excessive activation of the lipid peroxidation process in the brain tissue was not observed. Conclusion: The presented new model of the isolated brain perfusion may be used in experiments with other isolated organs and in studies of toxic effects of oxygen.

© 2019 Elsevier B.V. A massive-scale production of engineered nanoparticles (ENPs) becomes one of the most important environmental issues. The mechanisms of ENPs' (eco)toxic action are not fully understood, and the estimation of those mechanisms is a complicated task because even slight changes in particle characteristics could dramatically change their toxicity. As a result of continuous manufacturing of ENPs with specific functionality and different physicochemical properties, conventional methods of in vivo and in vitro testing would not be able to fill the existing knowledge gap in nanotoxicology. The objectives of this review are to overlook the current achievements based on the new approaches of ENPs' risk assessment, such as bioinformatics approaches and machine learning tools. These methods confirmed their ability to reliable prediction and evaluation of ENPs' behavior and their toxic endpoints. Databases and projects based on these methods and approaches would be highly useful in addressing the problem of ENPs’ regulation.

© 2019 Elsevier Inc. Most epidemiological research on alcohol as a risk factor is based on the assumption that outcomes are linked to pattern and level of alcohol exposure, where different beverages are converted into grams of ethanol. This review examines this basic assumption, that alcohol has the same impact, independent of beverage type. We conducted a systematic search on comparative research of beverage-specific alcohol exposure and consequences. Research was divided by methodology (survey, case–control, cohort, time-series analyses, interventional research). Overall, many studies showed higher risks for spirits compared to beer or wine; however, most research was not controlled adequately for confounders such as patterns of drinking. While there is no conclusive evidence for spirits being associated with more harm, given the same pattern and level of alcohol exposure, some evidence supports for certain outcomes such as injuries and poisonings, a potential excess risk with spirits consumption due to rapid ethanol intake and intoxication. Accordingly, encouraging people to opt for beverages with lower alcohol content via taxation strategies has the potential to reduce alcohol-attributable harm. This does not necessarily involve switching beverage type, but also can achieved within the same beverage category, by shifting from higher to lower concentration beverages.

© 2019 Elsevier B.V. Application of restructured collagen-based biomaterials is generally restricted by their poor mechanical properties, which ideally must be close to those of a tissue being repaired. Here, we present an approach to the formation of a robust biomaterial using laser-induced curing of a photosensitive star-shaped polylactide. The created collagen-based structures demonstrated an increase in the Young's modulus by more than an order of magnitude with introduction of reinforcing patterns (from 0.15 ± 0.02 MPa for the untreated collagen to 51.2 ± 5.6 MPa for the reinforced collagen). It was shown that the geometrical configuration of the created reinforcing pattern affected the scaffold's mechanical properties only in the case of a relatively high laser radiation power density, when the effect of accumulated thermomechanical stresses in the photocured regions was significant. Photo-crosslinking of polylactide did not compromise the scaffold's cytotoxicity and provided fluorescent regions in the collagen matrix, that create a potential for noninvasive monitoring of such materials' biodegradation kinetics in vivo.

© 2018, © 2018 Informa UK Limited, trading as Taylor  &  Francis Group. Background: Mesenchymal dysplasias or inherited connective tissue diseases are the group of diseases with deficiency of various components of connective tissue. Connective tissue disorders can affect different organs: skeleton, sight organ, skin, lungs, heart. But the most dangerous is vascular wall insufficiency leading to high risk of hemorrhage, especially during pregnancy and delivery due to hemodynamic and hormonal effects on the walls of the modified vessels. Aim: To evaluate the risk of complications during the pregnancy and delivery in patients with mesenchymal dysplasias. Study design: Fifty-six pregnancies in patients with mesenchymal dysplasias, including subclinical forms of diseases: 23 with Marfan syndrome (I group), 22 with Ehlers–Danlos syndrome (II group), and 11 with Osler–Weber–Rendu syndrome (hereditary hemorrhagic telangiectasia) (III group) of the age from 18 to 36. The study included retrospective analysis (for the period from 1993 to 2005) and prospective study. Results of study showed high risk of life-threatening complications during pregnancy and delivery, especially the risk of hemorrhage and cardiovascular complications. In all the patients, we observed the progression of bleeding or development of bleeding in new localizations (epistaxis in 27 patients, easy brushing in 22, skin and mucosa telangiectasia in 20, gastrointestinal bleedings in 4, hemoptysis in 4, hematomas for minor traumas in 14, conjunctivas hemorrhages in 5). Conclusion: The pathogenesis of bleeding in such patients has mixed pattern: besides vascular wall pathology coagulation deficiency plays some role. The preferred delivery method for such patients is caesarean section. Deep vaginal ruptures and serious hemorrhage accompany vaginal delivery.

© 2019 Most researchers associate the increase in the permeability of lipid bilayers of artificial and biological membranes observed in various experiments with the formation of hypothetical hydrophobic and hydrophilic pores. Although the existence of hydrophobic defects, as the first stage of the formation of a hydrophilic pore, was hypothesized decades ago from electroporation experiments, the difficulty of describing this stage is determined by the lack of experimental data confirming the existence or at least associated with hydrophobic pores. We explored the increase in the current variance through the lipid membrane, observed when approaching the phase transition from the side of high temperatures, and have associated it with capacitive currents arising in response to the formation of hydrophobic pores. Assuming that the number of hydrophobic pores in a membrane follows a Poisson distribution, and thus, the mean number of hydrophobic pores is equal to the variance of that number, we used the measurements of the membrane current variance to evaluate the number of hydrophobic pores. Analysis of experimental data within this model allows us to estimate the number of hydrophobic pores at or above the phase transition and shows that the number of hydrophobic pores in a membrane close to the phase transition increased 20 times compared to the number of hydrophobic pores existing in the membrane far from the melting transition.

© 2019 Solventless and solid-state reactions have become increasingly popular and appealing options in the field of green chemistry and process intensification as they can often minimise waste and energy costs. A variety of strategies and protocols (in particular ball milling, dielectric heating and reactive extrusion) have been developed and improved over the last two decades. Although this account cannot be comprehensive, it will, however, provide a glimpse of such methods, highlight the advantages and limitations of strategies and discuss some mechanistic considerations. A few examples for each case, often from our own laboratories, will be used to illustrate specific applications.

© 2019 Elsevier Ltd Immunosuppressive chemoresistance is a major barrier in lung cancer treatment. Tumor immunosuppressive environments mediated by myeloid-derived suppressor cells (MDSCs) play a key role in chemotherapy induced MDSC development and differentiation but their mechanistic role has not been elucidated. Here, we define a role for carboplatin based chemotherapy in potentiating an MDSC-dependent pathway that triggers the chemoresistance mechanism. Findings reveal MDSC differentiation and activation of IL-13/IL-33-mediated pathway through VCAM/RANTES following carboplatin treatment. Furthemore, secretion of T regulatory IL-10-producing CD4+Foxp3+ cells was increased followed by expression of co-inhibitory receptor TIGIT on T cells, leading to a dysfunctional T cell phenotype. These cells were characterized by an immunosuppressive phenotype with impaired activation, proliferation and cytokine production. Lung cancer tissues expressed CD155, which bound TIGIT receptors and inactivated CD8 T cells. This TIGIT expression on tumor-infiltrating T cells was found to be associated with tumor progression and was linked to functional exhaustion of T cells. In addition, the presence of plasmacytoid dendritic cells (pDCs) exposed to tumor-derived factors further enhanced tumor progression through IL-10 production and up-regulation of the inducible co-stimulatory ligand (ICOS-L). Deciphering these deranged immune mechanisms and how they are impacted by chemotherapy induction is essential for incorporation of novel immune-based strategies in order to restore immunity and inhibit the immunosuppressive phenotype of metastatic lung cancer.

© 2019 Elsevier B.V. Fabry disease (FD [MIM:301500]) is an X-linked lysosomal storage disorder caused by mutations in the GLA gene. Deficient activity of its product, lysosomal enzyme α-galactosidase A (α-Gal A), leads to excessive accumulation of glycosphingolipids in cells of multiple organs. The establishing of the diagnosis is challenge in female patients because of milder clinical manifestation and normal α-Gal A activity. The globotriaosylsphingosine (lysoGb3) is described as a more sensitive diagnostic biomarker for females with pathogenic mutation in the GLA gene. Thus, the aim of this study is to improve the biochemical diagnostic efficiency for FD in females. Here we report the α-Gal A/lysoGb3 ratio as the novel biochemical criteria for diagnosis of female patients with FD, using dried blood spots (DBS) as test samples. It showed 100% sensitivity in distinguishing our group of 35 female patients from control (n = 140). Whereas measurement of α-Gal A and lysoGb3 alone showed 8.6% and 74.4% respectively. A new approach of using the ratio of α-Gal A activity to lysoGb3 concentration in DBS may provide a more accurate screening tool for identification of FD females.

© 2019 The Authors Immunosuppressive chemoresistance is a major challenge in lung cancer treatment. Exosomes present in the tumor microenviroment are implicated in chemoresistant-related immune suppression, and metastasis but the exact pathogenic role of lung-derived exosomes is still uncertain. Recent reports reveal that lung cancer pathogenesis is strictly associated with a exosomal tumor supportive status and a dysfunctional immune system. In this study, we investigate the role of Kras-derived exosomes in chemoresistant immunosuppression in which neoplastic cells create a metabolic-sustained microenvironment. Findings reveal that Kras-derived exosomes induce regulation of SMARCE1/NCOR1 chromatin remodeling genes promoting pre-metastatic niche formation in naive mice and consequently increase lung metastatic burden. Furthermore, exosomal Kras inhibition downregulated transcription factor BACH2/GATA-3 expression in lung tumor tissues by shifting pyruvate/PKM2 dependent metabolism, contributing to a tumor-restraining status. Further co-treatment with carboplatin triggered RIP3/TNFa dependent necroptosis in ex vivo cells accompanied by differential expression of immunosuppressive miR-146/miR-210 regulators in metastatic lung cancer patients. Overall, these findings demonstrate the multifaceted roles of Kras-derived exosomes in sustaining lung immunosuppressive metastasis and provide new opportunities for effective metastasis inhibition, especially in chemoresistant tumors.

© 2019 The field of cartilage tissue engineering has been evolved in the last decade and a myriad of scaffolding biomaterials and bioactive agents have been proposed. Controlled release of growth factors encapsulated in the polymeric nanomaterials has been of interest notably for the repair of damaged articular cartilage. Here, we proposed an on-chip hydrodynamic flow focusing microfluidic approach for synthesis of alginate nanogels loaded with the transforming growth factor beta 3 (TGF-β3) through an ionic gelation method in order to achieve precise release profile of these bioactive agents during chondrogenic differentiation of mesenchymal stem cells (MSCs). Alginate nanogels with adjustable sizes were synthesized by fine-tuning the flow rate ratio (FRR) in the microfluidic device consisting of cross-junction microchannels. The result of present study showed that the proposed approach can be a promising tool to synthesize bioactive -loaded polymeric nanogels for applications in drug delivery and tissue engineering.

© 2019 The Royal College of Radiologists AIM: To report prostate cancer (PCa) prevalence in Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) categories and investigate the potential to avoid unnecessary, magnetic resonance imaging (MRI)-guided in-bore biopsies by adding clinical and biochemical patient characteristics. MATERIALS AND METHODS: The present institutional review board-approved, prospective study on 137 consecutive men with 178 suspicious lesions on 3 T MRI was performed. Routine data collected for each patient included patient characteristics (age, prostate volume), clinical background information (prostate-specific antigen [PSA] levels, PSA density), and PI-RADS v2 scores assigned in a double-reading approach. RESULTS: Histopathological evaluation revealed a total of 93/178 PCa (52.2%). The mean age was 66.3 years and PSA density was 0.24 ng/ml2 (range, 0.04–0.89 ng/ml). Clinically significant PCa (csPCa, Gleason score >6) was confirmed in 50/93 (53.8%) lesions and was significantly associated with higher PI-RADS v2 scores (p=0.0044). On logistic regression analyses, age, PSA density, and PI-RADS v2 scores contributed independently to the diagnosis of csPCa (p=7.9×10−7, p=0.097, and p=0.024, respectively). The resulting area under the receiver operating characteristic curve (AUC) to predict csPCa was 0.76 for PI-RADS v2, 0.59 for age, and 0.67 for PSA density. The combined regression model yielded an AUC of 0.84 for the diagnosis of csPCa and was significantly superior to each single parameter (p≤0.0009, respectively). Unnecessary biopsies could have been avoided in 50% (64/128) while only 4% (2/50) of csPCa lesions would have been missed. CONCLUSIONS: Adding age and PSA density to PI-RADS v2 scores improves the diagnostic accuracy for csPCa. A combination of these variables with PI-RADS v2 can help to avoid unnecessary in-bore biopsies while still detecting the majority of csPCa.

© 2018, © 2018 Informa UK Limited, trading as Taylor  &  Francis Group. Background: Mesenchymal dysplasias or inherited connective tissue diseases are the group of diseases with deficiency of various components of connective tissue. Connective tissue disorders can affect different organs: skeleton, sight organ, skin, lungs, heart. But the most dangerous is vascular wall insufficiency leading to high risk of hemorrhage, especially during pregnancy and delivery due to hemodynamic and hormonal effects on the walls of the modified vessels. Aim: To evaluate the risk of complications during the pregnancy and delivery in patients with mesenchymal dysplasias. Study design: Fifty-six pregnancies in patients with mesenchymal dysplasias, including subclinical forms of diseases: 23 with Marfan syndrome (I group), 22 with Ehlers–Danlos syndrome (II group), and 11 with Osler–Weber–Rendu syndrome (hereditary hemorrhagic telangiectasia) (III group) of the age from 18 to 36. The study included retrospective analysis (for the period from 1993 to 2005) and prospective study. Results of study showed high risk of life-threatening complications during pregnancy and delivery, especially the risk of hemorrhage and cardiovascular complications. In all the patients, we observed the progression of bleeding or development of bleeding in new localizations (epistaxis in 27 patients, easy brushing in 22, skin and mucosa telangiectasia in 20, gastrointestinal bleedings in 4, hemoptysis in 4, hematomas for minor traumas in 14, conjunctivas hemorrhages in 5). Conclusion: The pathogenesis of bleeding in such patients has mixed pattern: besides vascular wall pathology coagulation deficiency plays some role. The preferred delivery method for such patients is caesarean section. Deep vaginal ruptures and serious hemorrhage accompany vaginal delivery.

© 2019 Most researchers associate the increase in the permeability of lipid bilayers of artificial and biological membranes observed in various experiments with the formation of hypothetical hydrophobic and hydrophilic pores. Although the existence of hydrophobic defects, as the first stage of the formation of a hydrophilic pore, was hypothesized decades ago from electroporation experiments, the difficulty of describing this stage is determined by the lack of experimental data confirming the existence or at least associated with hydrophobic pores. We explored the increase in the current variance through the lipid membrane, observed when approaching the phase transition from the side of high temperatures, and have associated it with capacitive currents arising in response to the formation of hydrophobic pores. Assuming that the number of hydrophobic pores in a membrane follows a Poisson distribution, and thus, the mean number of hydrophobic pores is equal to the variance of that number, we used the measurements of the membrane current variance to evaluate the number of hydrophobic pores. Analysis of experimental data within this model allows us to estimate the number of hydrophobic pores at or above the phase transition and shows that the number of hydrophobic pores in a membrane close to the phase transition increased 20 times compared to the number of hydrophobic pores existing in the membrane far from the melting transition.

© 2019 Solventless and solid-state reactions have become increasingly popular and appealing options in the field of green chemistry and process intensification as they can often minimise waste and energy costs. A variety of strategies and protocols (in particular ball milling, dielectric heating and reactive extrusion) have been developed and improved over the last two decades. Although this account cannot be comprehensive, it will, however, provide a glimpse of such methods, highlight the advantages and limitations of strategies and discuss some mechanistic considerations. A few examples for each case, often from our own laboratories, will be used to illustrate specific applications.

© 2019 Elsevier Ltd Immunosuppressive chemoresistance is a major barrier in lung cancer treatment. Tumor immunosuppressive environments mediated by myeloid-derived suppressor cells (MDSCs) play a key role in chemotherapy induced MDSC development and differentiation but their mechanistic role has not been elucidated. Here, we define a role for carboplatin based chemotherapy in potentiating an MDSC-dependent pathway that triggers the chemoresistance mechanism. Findings reveal MDSC differentiation and activation of IL-13/IL-33-mediated pathway through VCAM/RANTES following carboplatin treatment. Furthemore, secretion of T regulatory IL-10-producing CD4+Foxp3+ cells was increased followed by expression of co-inhibitory receptor TIGIT on T cells, leading to a dysfunctional T cell phenotype. These cells were characterized by an immunosuppressive phenotype with impaired activation, proliferation and cytokine production. Lung cancer tissues expressed CD155, which bound TIGIT receptors and inactivated CD8 T cells. This TIGIT expression on tumor-infiltrating T cells was found to be associated with tumor progression and was linked to functional exhaustion of T cells. In addition, the presence of plasmacytoid dendritic cells (pDCs) exposed to tumor-derived factors further enhanced tumor progression through IL-10 production and up-regulation of the inducible co-stimulatory ligand (ICOS-L). Deciphering these deranged immune mechanisms and how they are impacted by chemotherapy induction is essential for incorporation of novel immune-based strategies in order to restore immunity and inhibit the immunosuppressive phenotype of metastatic lung cancer.