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991.
Jacek Jassem Natalia Maria Marek-Trzonkowska Tomasz Smiatacz ukasz Arcimowicz Ines Papak Ewa Jassem Jan Maciej Zaucha 《International journal of molecular sciences》2021,22(20)
We report a lymphoma patient with profound B-cell deficiency after chemotherapy combined with anti-CD20 antibody successfully treated with remdesivir and convalescent plasma for prolonged SARS-CoV-2 infection. Viral clearance was likely attributed to the robust expansion and activation of TCR Vβ2 CD8+ cytotoxic T cells and CD16 + CD56- NK cells. This is the first presentation of TCR-specific T cell oligoclonal response in COVID-19. Our study suggests that B-cell depleted patients may effectively respond to anti-SARS-CoV-2 treatment when NK and antigen-specific Tc cell response is induced. 相似文献
992.
Tomasz Kloskowski Kamil Szeliski Zuzanna Fekner Marta Rasmus Pawe Dbrowski Aleksandra Wolska Natalia Siedlecka Jan Adamowicz Tomasz Drewa Marta Pokrywczyska 《International journal of molecular sciences》2021,22(21)
Introduction: Introducing new drugs for clinical application is a very difficult, long, drawn-out, and costly process, which is why drug repositioning is increasingly gaining in importance. The aim of this study was to analyze the cytotoxic properties of ciprofloxacin and levofloxacin on bladder and prostate cell lines in vitro. Methods: Bladder and prostate cancer cell lines together with their non-malignant counterparts were used in this study. In order to evaluate the cytotoxic effect of both drugs on tested cell lines, MTT assay, real-time cell growth analysis, apoptosis detection, cell cycle changes, molecular analysis, and 3D cultures were examined. Results: Both fluoroquinolones exhibited a toxic effect on all of the tested cell lines. In the case of non-malignant cell lines, the cytotoxic effect was weaker, which was especially pronounced in the bladder cell line. A comparison of both fluoroquinolones showed the advantage of ciprofloxacin (lower doses of drug caused a stronger cytotoxic effect). Both fluoroquinolones led to an increase in late apoptotic cells and an inhibition of cell cycle mainly in the S phase. Molecular analysis showed changes in BAX, BCL2, TP53, and CDKN1 expression in tested cell lines following incubation with ciprofloxacin and levofloxacin. The downregulation of topoisomerase II genes (TOP2A and TOP2B) was noticed. Three-dimensional (3D) cell culture analysis confirmed the higher cytotoxic effect of tested fluoroquinolone against cancer cell lines. Conclusions: Our results suggest that both ciprofloxacin and levofloxacin may have great potential, especially in the supportive therapy of bladder cancer treatment. Taking into account the low costs of such therapy, fluoroquinolones seem to be ideal candidates for repositioning into bladder cancer therapeutics. 相似文献
993.
Tomasz Ochrymiuk 《热科学学报(英文版)》2017,26(5):459-464
Numerical simulations were performed to predict the film cooling effectiveness on the fiat plate with a three-dimensional discrete hole film cooling RSM-AKN turbulent heat transfer models based on variable turbulent Prandtl number approaches were considered.Obtained numerical results were directly compared with the data that came from an experiment based on Transient Liquid Crystal methodology.All implemented models for turbulent heat transfer performed sufficiently well for the considered case.It was confirmed,however,that the two-equation closure can give a detailed look into film cooling problems without using any time-consuming and inherently unsteady models.The RSM-AKN turbulent model was used in micoholes case too.The main target of simulations was maintain the same level of cooling efficiency ratio in both cases and confirm that is possible significantly reduce mass flows of the coolant in microholes case. 相似文献
994.
Malgorzata Tyszka-Czochara Marzena Suder Agnieszka Dohaczuk-
rdka Magorzata Rajfur Katarzyna Grata Micha Starosta Agnieszka Jagoda-Pasternak Wiktor Kasprzyk Anna K. Nowak Saeid Ahmadzadeh Dorota Kope Piotr Suryo Tomasz
wiergosz Katarzyna M. Stadnicka 《International journal of molecular sciences》2022,23(2)
Innovative engineering design for biologically active hydroxyapatites requires enhancing both mechanical and physical properties, along with biocompatibility, by doping with appropriate chemical elements. Herein, the purpose of this investigation was to evaluate and elucidate the model of naturally occurring hydroxyapatite and the effects of doped trace elements on the function of normal human fibroblasts, representing the main cells of connective tissues. The substrates applied (geological apatites with hexagonal prismatic crystal habit originated from Slyudyanka, Lake Baikal, Russia (GAp) and from Imilchil, The Atlas Mountains, Morocco (YAp)) were prepared from mineral natural apatite with a chemical composition consistent with the building blocks of enamel and enriched with a significant F− content. Materials in the form of powders, extracts and single-crystal plates have been investigated. Moreover, the effects on the function of fibroblasts cultured on the analyzed surfaces in the form of changes in metabolic activity, proliferation and cell morphology were evaluated. Apatite plates were also evaluated for cytotoxicity and immune cell activation capacity. The results suggest that a moderate amount of F− has a positive effect on cell proliferation, whereas an inhibitory effect was attributed to the Cl− concentration. It was found that for (100) GAp plate, fibroblast proliferation was significantly increased, whereas for (001) YAp plate, it was significantly reduced, with no cytotoxic effect and no immune response from macrophages exposed to these materials. The study of the interaction of fibroblasts with apatite crystal surfaces provides a characterization relevant to medical applications and may contribute to the design of biomaterials suitable for medical applications and the evaluation of their bioavailability. 相似文献
995.
Tomasz Lepionka Magorzata Biaek Marian Czauderna Micha Szlis Agnieszka Biaek 《International journal of molecular sciences》2022,23(1)
Among the risk factors affecting the development of cancer, nutritional factors occupy a significant place. Pomegranate seed oil (PSO) and bitter melon extract (BME), used for ages in folk medicine, are nowadays used in the prevention of many diseases and as ingredients of dietary supplements. Despite numerous publications on these raw materials or their active substances, their mechanism of action in various pathological states has not been recognized yet, nor has the safety of their simultaneous use been evaluated. The study aimed to assess how dietary supplementation with either PSO, with BME, or both, affects fatty acids’ profiles and their metabolism in hepatic microsomes, as well as the activity of selected microsomal enzymes (COX-2 and CYP1B1). Experimental animals (Sprague-Dawley rats) were divided into eight parallel experimental groups, differing in applied dietary modifications (control, PSO, BME and both PSO and BME) and introduction of chemical carcinogen—7,12-dimethylbenz[a]nthracene. Obtained results indicated the pronounced effect of the cancerous process on lipid metabolism and demonstrated the antagonistic effect of applied dietary supplements on the content of individual fatty acids and the activity of CYP1B1 and COX-2. The applied broad analytical approach and chemometric data analysis confirmed that raw materials, for which potential cancer prevention has been previously demonstrated, may differ in effects depending on the coexisting pathological state. 相似文献
996.
Izabela
wietlicka Siemowit Muszyski Carina Prein Hauke Clausen-Schaumann Attila Aszodi Marcin B. Arciszewski Tomasz Blicharski Mariusz Gago Micha
wietlicki Piotr Dobrowolski Katarzyna Kras Ewa Tomaszewska Marta Arczewska 《International journal of molecular sciences》2021,22(17)
The potential of Fourier Transform infrared microspectroscopy (FTIR microspectroscopy) and multivariate analyses were applied for the classification of the frequency ranges responsible for the distribution changes of the main components of articular cartilage (AC) that occur during dietary β-hydroxy-β-methyl butyrate (HMB) supplementation. The FTIR imaging analysis of histological AC sections originating from 35-day old male piglets showed the change in the collagen and proteoglycan contents of the HMB-supplemented group compared to the control. The relative amount of collagen content in the superficial zone increased by more than 23% and in the middle zone by about 17%, while no changes in the deep zone were observed compared to the control group. Considering proteoglycans content, a significant increase was registered in the middle and deep zones, respectively; 62% and 52% compared to the control. AFM nanoindentation measurements collected from animals administered with HMB displayed an increase in AC tissue stiffness by detecting a higher value of Young’s modulus in all investigated AC zones. We demonstrated that principal component analysis and artificial neural networks could be trained with spectral information to distinguish AC histological sections and the group under study accurately. This work may support the use and effectiveness of FTIR imaging combined with multivariate analyses as a quantitative alternative to traditional collagenous tissue-related histology. 相似文献
997.
Kamila Wojas-Krawczyk Iwona Panik Tomasz Kucharczyk Irena Wieleba Natalia Krzyanowska Micha Gil Pawe Krawczyk Janusz Milanowski 《International journal of molecular sciences》2021,22(17)
The efficiency of immunotherapy using monoclonal antibodies that inhibit immune checkpoints has been proven in many clinical studies and well documented by numerous registration approaches. To date, PD-L1 expression on tumor and immune cells, tumor mutation burden (TMB), and microsatellite instability (MSI) are the only validated predictive factors used for the qualification of cancer patients for immunotherapy. However, they are not the ideal predictive factors. No response to immunotherapy could be observed in patients with high PD-L1 expression, TMB, or MSI. On the other hand, the effectiveness of this treatment method also may occur in patients without PD-L1 expression or with low TMB and with microsatellite stability. When considering the best predictive factor, we should remember that the effectiveness of immunotherapy relies on an overly complex process depending on many factors. To specifically stimulate lymphocytes, not only should their activity in the tumor microenvironment be unlocked, but above all, they should recognize tumor antigens. The proper functioning of the anticancer immune system requires the proper interaction of many elements of the specific and non-specific responses. For these reasons, a multi-parameter analysis of the immune system at its different activity levels is considered a very future-oriented predictive marker. Such complex immunological analysis is performed using modern molecular biology techniques. Based on the gene expression studies, we can determine the content of individual immune cells within the tumor, its stroma, and beyond. This includes all cell types from active memory cytotoxic T cells, M1 macrophages, to exhausted T cells, regulatory T cells, and M2 macrophages. In this article, we summarize the possibilities of using an immune system analysis to predict immunotherapy efficacy in cancer patients. Moreover, we present the advantages and disadvantages of immunoprofiling as well as a proposed future direction for this new method of immune system analysis in cancer patients who receive immunotherapy. 相似文献
998.
999.
Buyse M Burzykowski T Michiels S Carroll K 《Statistical methods in medical research》2008,17(5):467-475
Two conditions must be fulfilled for an intermediate endpoint to be an acceptable surrogate for a true clinical endpoint: (1) there must be a strong association between the surrogate and the true endpoint, and (2) there must be a strong association between the effects of treatment on the surrogate and the true endpoint. We test whether these conditions are fulfilled for disease-free survival (DFS) and progression-free survival (PFS) on data from 20 clinical trials comparing experimental treatments with standard treatments for early and advanced colorectal cancer. The effects of treatment on DFS (or PFS in advanced disease) and OS were quantified through log hazard ratios (log HR), estimated through a Weibull model stratified for trial. The rank correlation coefficients between DFS and OS, and trial-specific treatment effects, were estimated using a bivariate copula distribution for these endpoints. A linear regression model between the estimated log hazard ratios was used to compute the "surrogate threshold effect", which is the minimum treatment effect on DFS required to predict a non-zero treatment effect on OS in a future trial. In early disease, the rank correlation coefficient between DFS and OS was equal to 0.96 (CI 0.95-0.97). The correlation coefficient between the log hazard ratios was equal to 0.94 (CI 0.87-1.01). The risk reductions were approximately 3% smaller on OS than on DFS, and the surrogate threshold effect corresponded to a DFS hazard ratio of 0.93. In advanced disease, the rank correlation coefficient between PFS and OS was equal to 0.82 (CI 0.82-0.83). The correlation coefficient between the log hazard ratios was equal to 0.99 (CI 0.94-1.04). The risk reductions were approximately 19% smaller on OS than on PFS, and the surrogate threshold effect corresponded to a PFS hazard ratio of 0.86. One trial with a large treatment effect on PFS and OS had a strong influence on the results in advanced disease. DFS (and PFS in advanced disease) are acceptable surrogates for OS in colorectal cancer. 相似文献
1000.
The conductive properties of butadiene polymer (BR) and styrene-butadiene polymer (SBR) with sodium chlorate (VII) can be used at industrial scale as miniature batteries. Polymer material modified with sodium chlorate (VII) was used to produce sodium polybutadiene and poly(styrene-butadiene) batteries. The conductivity of such polymer composites for temperatures ranging 243–313 K is at a similar level and amounts to 10−4 S cm−1 for butadiene polymer and to 10−3 S cm−1 for styrene-butadiene polymer at 100 kHz. The conductive battery made of butadiene polymer shows a open circuit voltage of 0.9 V with a short-circuit current of 40 mA, whereas that made of styrene-butadiene polymer shows a open circuit voltage of 1.2 V with a short-circuit current of 38 mA. The lightness, commonly found material (sodium), and environment-friendly energy are main advantages of sodium polybutadiene and poly(styrene-butadiene) batteries. 相似文献