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991.
Tomasz S. Wiltowski Kurt Sangster William S. O'Brien 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1996,67(2):204-212
This paper deals with catalytic reduction of SO2 with methane using molybdenum sulfide catalyst supported on two different activated carbons (Darco TRS and Norit ROZ-3). The experiments evaluated the effects of MoS2 catalyst loading (10%, 15%, and 20% Mo, by weight), gas feed-rate concentration ratios of CH4 to SO2 (CH4: SO2 ratios of 2: 1, 1: 1, and 1: 2) and reaction temperatures (450°C, 500°C, and 600°C). The reactivity of each catalyst was evaluated by three different parameters: (a) SO2 conversion, (b) CH4 conversion and (c) the yield of elemental sulfur. The results show that the catalytic activity of MoS2 supported on activated carbons is strongly related to the reaction temperature and the CH4 : SO2 feed ratio, with a secondary dependency on the loading of the MoS2. The 20% MoS2 catalyst supported on Darco TRS in a reactor stream with CH4 : SO2 = 1 : 1 demonstrated the highest activity of all the catalysts tested, having an SO2 conversion of 99·8%. At 600°C and with a CH4 : SO2 = 1 : 1, the catalysts with 20% loading supported on both Dacro TRS and Norit ROZ-3 exhibited comparable SO2 conversion, both above 90%. 相似文献
992.
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
993.
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
994.
Anna Bogda Andrzej Badeski Magorzata Pac Anna Wjcicka Marta Badeska Agnieszka Didyk Elbieta Trembecka-Dubel Nel Dbrowska-Leonik Magorzata Walaszczyk Natalia Matysiak Aurelia Morawiec-Knysak Tomasz Szczepaski Maria Szczepaska 《International journal of molecular sciences》2021,22(17)
Hemolytic uremic syndrome (HUS) is defined by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury (AKI). Atypical HUS (aHUS), distinguished by its etiology, is caused by uncontrolled overactivation of the alternative complement pathway. The correct diagnosis of aHUS is complex and involves various gene mutations. Severe combined immunodeficiency (SCID), characterized by severe T-cell lymphocytopenia and a lack of antigen-specific T-cell and B-cell immune responses, is of seldom occurrence. In 10–15% of pediatric patients, SCID is caused by adenosine deaminase (ADA) deficiency. The authors describe the case of a boy who suffered from both aHUS and ADA-deficient SCID. At the age of 9 months, the patient presented acute kidney injury with anuria and coagulopathy. The diagnosis of aHUS was established on the basis of alternative complement pathway deregulation and disease-associated gene mutations. Further examination revealed immune system failure and, at the age of 13 months, the ADA deficiency was confirmed by genetic tests and the boy was diagnosed with ADA-SCID. ADA SCID has recently been described as a possible triggering factor of aHUS development and progression. However, more research is required in this field. Nevertheless, it is crucial in clinical practice to be aware of these two co-existing life-threatening diseases. 相似文献
995.
Tomasz Kosicki 《先进制造进展(英文版)》2014,2(1):54-60
This paper investigates how graph representation can be created for the mesh which is a discrete approximation of n-dimensional continuous space. The paper discusses the relationship between mesh dimensionality and the type and quantity of edges connecting each vertex with its neighbors. Basing on the analysis, a simple algorithm is also proposed to create such graph representation. The purpose of the graph is to search optimal paths and trajectories in the represented space. 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.
Effect of supplementation of cows diet with linseed and fish oil and different variants of β‐lactoglobulin on fatty acid composition and antioxidant capacity of milk 下载免费PDF全文
998.
999.
Tomasz Wollny Urszula Wnorowska Ewelina Piktel ukasz Suprewicz Grzegorz Krl Katarzyna Guszek Stanisaw G
d
Janusz Kopczyski Robert Bucki 《International journal of molecular sciences》2022,23(13)
It has been proven that tumour growth and progression are regulated by a variety of mediators released during the inflammatory process preceding the tumour appearance, but the role of inflammation in the development of bladder cancer is ambiguous. This study was designed around the hypothesis that sphingosine-1-phosphate (S1P), as a regulator of several cellular processes important in both inflammation and cancer development, may exert some of the pro-tumorigenic effects indirectly due to its ability to regulate the expression of human cathelicidin (hCAP-18). LL-37 peptide released from hCAP-18 is involved in the development of various types of cancer in humans, especially those associated with infections. Using immunohistological staining, we showed high expression of hCAP-18/LL-37 and sphingosine kinase 1 (the enzyme that forms S1P from sphingosine) in human bladder cancer cells. In a cell culture model, S1P was able to stimulate the expression and release of hCAP-18/LL-37 from human bladder cells, and the addition of LL-37 peptide dose-dependently increased their proliferation. Additionally, the effect of S1P on LL-37 release was inhibited in the presence of FTY720P, a synthetic immunosuppressant that blocks S1P receptors. Together, this study presents the possibility of paracrine relation in which LL-37 production following cell stimulation by S1P promotes the development and growth of bladder cancer. 相似文献
1000.
The aim of this study was to verify the influence of bis(heptaphenylaluminosilsesquioxane) (AlPOSS), used as a curing agent, on the thermomechanical properties of epoxy resin. Moreover, various curing conditions were taken into account. Epoxy casts were prepared from epoxy resin based on bisphenol A cured with different amounts of bis(heptaphenylaluminosilsesquioxane). The thermomechanical properties were investigated during dynamical mechanical thermal analysis (DMTA) in two cycles of heating. The storage modulus G′ of the epoxy casts was found to be higher in comparison to the reference epoxy sample and significantly dependent on the POSS content. A correlation between the glass transition temperatures (Tg), the curing conditions and the amount of curing agents were closely related. The occurrence of the crosslinking process in epoxy matrix was proved by the FTIR spectroscopy. The structure of the epoxy casts was investigated using scanning electron microscopy (SEM). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40672. 相似文献