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Background: Standard approaches to the treatment of chronic post-radiation proctitis are associated with a high risk of complications and a high percentage of unsatisfactory results due to the reduced regenerative potential of irradiated tissues. Regenerative surgery techniques using the stromal-vascular cell fraction (SVF) based on the patient's autologous adipose tissue are a promising direction for study. Clinical case description: A 76-year-old patient suffering from chronic post-radiation erosive-ulcerative proctitis, grade 4 according to RTOG–EORTC, complicated by recurrent profuse rectal bleeding, underwent local autotransplantation of SVF into the submucosal layer of the rectum and pararectal connective tissue. The follow-up colonoscopies 1 and 6 months after the surgery and histological examination showed the complete epithelialization of ulcerative defects and a decrease in proctitis activity. There were no bleeding episodes during the 12-month postoperative observation period. Conclusion: The proangiogenic, wound-healing, and anti-apoptotic effects of the SVF cell suspension provided reduction of inflammation activity, epithelialization of ulcers, and elimination of defecation-associated hemorrhage, following the SVF injection into the submucosal layer of the rectal wall and pararectal connective tissue in a patient with post-radiation proctitis with ulcers and recurrent bleeding. [ABSTRACT FROM AUTHOR]

Background: Standard approaches to the treatment of chronic post-radiation proctitis are associated with a high risk of complications and a high percentage of unsatisfactory results due to the reduced regenerative potential of irradiated tissues. Regenerative surgery techniques using the stromal-vascular cell fraction (SVF) based on the patient's autologous adipose tissue are a promising direction for study. Clinical case description: A 76-year-old patient suffering from chronic post-radiation erosive-ulcerative proctitis, grade 4 according to RTOG–EORTC, complicated by recurrent profuse rectal bleeding, underwent local autotransplantation of SVF into the submucosal layer of the rectum and pararectal connective tissue. The follow-up colonoscopies 1 and 6 months after the surgery and histological examination showed the complete epithelialization of ulcerative defects and a decrease in proctitis activity. There were no bleeding episodes during the 12-month postoperative observation period. Conclusion: The proangiogenic, wound-healing, and anti-apoptotic effects of the SVF cell suspension provided reduction of inflammation activity, epithelialization of ulcers, and elimination of defecation-associated hemorrhage, following the SVF injection into the submucosal layer of the rectal wall and pararectal connective tissue in a patient with post-radiation proctitis with ulcers and recurrent bleeding. [ABSTRACT FROM AUTHOR]

We present the results of studying the impact of high-intensity terahertz pulses on the differentiation of induced human neural progenitor cells (drNPCs). The differentiation was estimated using the immunocytochemical analysis, i.e., the marker of the undifferentiated cells (SOX2) and the markers of the neuronal (β-III-tubulin and MAP2b) and glial (GFAP) phenotype. The cell exposure was performed by terahertz pulses with an intensity of 21 GW/cm2 and an electric field of 2.8 MV/cm for 30 min. As a result of exposure, the phenotype of induced neural progenitor cells did not differ from that of unexposed cells and the appearance of mature neurons or glial cells was not detected. The ability of the terahertz radiation to cause effects in neural cell cultures apparently requires further studies for higher exposure intensity or duration. [ABSTRACT FROM AUTHOR]

Exposure of cells or biological tissues to high-power pulses of terahertz (THz) radiation leads to changes in a variety of intracellular processes. However, the role of heating effects due to strong absorption of THz radiation by water molecules still stays unclear. In this study, we performed numerical modelling in order to estimate the thermal impact on water of a single THz pulse as well as a series of THz pulses. A finite-element (FE) model that provides numerical solutions for the heat conduction equation is employed to compute the temperature increase. A simple expression for temperature estimation in the center of the spot of THz radiation is presented for given frequency and fluence of the THz pulse. It has been demonstrated that thermal effect is determined by either the average power of radiation or by the fluence of a single THz pulse depending on pulse repetition rate. Human dermal fibroblasts have been exposed to THz pulses (with an energy of 15 μ J and repetition rate of 100 Hz) to estimate the thermal effect. Analysis of heat shock proteins expression has demonstrated no statistically significant difference ( p < 0.05 ) between control and experimental groups after 3 h of irradiation. [ABSTRACT FROM AUTHOR]

In this paper we present an experimental set up for long-term irradiation of cells with high-power terahertz pulses with intensities of about 23 GW/cm2. The system was shown to be a reliable tool for cell irradiation in single-point irradiation mode as well as in scanning mode. Wharton's Jelly derived mesenchymal stem cells were exposed to high power THz pulses with a field strength of about 3 MV/cm for 90 min for the first time. Preliminary results on THz radiation effects on cell viability and proliferation were obtained. [ABSTRACT FROM AUTHOR]

In in vitro experiments on cultures of human multipotent stem cells from the human bone arrow and dental pulp, we studied direct reprogramming towards neuro-glial lineage cells using a cocktail of small molecules. Reprogramming by the previously published protocol (with a cocktail containing β-mercaptoethanol, LIF, VPA, CHIR99021, and RepSox) and by the optimized protocol (VPA, RG108, А83-01, dorsomorphin, thiazovivin, CHIR99021, forskolin, and Isx9) allows obtaining cells with immunophenotypic and genetic signs of neural stem cells. However, neither the former, nor the optimized protocols allowed preparing neural progenitors capable of adequate terminal differentiation from both bone marrow-derived mesenchymal stem cells and nestin-positive neural crest-derived mesenchymal stem cells. Real-time PCR demonstrated the expression of some neurogenesis markers, but neural stem cell-specific expression pattern was not observed. The findings lead us to a conclusion that reprogramming with small molecules without additional factors modifying gene expression does not allow reproducible production of human neural stem cell-like progenitors that can be used as the source of neural tissue for the regenerative therapy. [ABSTRACT FROM AUTHOR]

In in vitro experiments on cultures of human multipotent stem cells from the human bone arrow and dental pulp, we studied direct reprogramming towards neuro-glial lineage cells using a cocktail of small molecules. Reprogramming by the previously published protocol (with a cocktail containing β-mercaptoethanol, LIF, VPA, CHIR99021, and RepSox) and by the optimized protocol (VPA, RG108, А83-01, dorsomorphin, thiazovivin, CHIR99021, forskolin, and Isx9) allows obtaining cells with immunophenotypic and genetic signs of neural stem cells. However, neither the former, nor the optimized protocols allowed preparing neural progenitors capable of adequate terminal differentiation from both bone marrow-derived mesenchymal stem cells and nestin-positive neural crest-derived mesenchymal stem cells. Real-time PCR demonstrated the expression of some neurogenesis markers, but neural stem cell-specific expression pattern was not observed. The findings lead us to a conclusion that reprogramming with small molecules without additional factors modifying gene expression does not allow reproducible production of human neural stem cell-like progenitors that can be used as the source of neural tissue for the regenerative therapy. [ABSTRACT FROM AUTHOR]

Combined use of complexes of the most active chemotherapeutic drugs and detonation nanodiamonds (DND) is a new trend in cancer therapy, which is probably related to selective chemotherapeutic drug delivery by DND to the zone of so-called cancer stem cells (CSC). Stable DND complexes of 4-5 nm size with salinomycin-a strong CSC inhibitor-have been obtained (as a suspension). It has been demonstrated that a complex administration considerably increases the drug antitumor effect on the transplantable tumor of LLC mice. A similar effect has been observed in CSC models in vivo, obtained by exposure of stem cells of normal mice tissues to a carcinogen 1,2-dimethylhydrazine. It has also been found out, that administration of DND complexes with the conditioned medium from mesenchymal stem cells (MSC) cultures to mice results in a considerable stimulation of stem cell pools in normal mice tissues, which can be used in regenerative medicine. [ABSTRACT FROM AUTHOR]