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991.
Martin Roeb Martina NeisesJan-Peter Säck Peter RietbrockNathalie Monnerie Jürgen DerschMark Schmitz Christian Sattler 《International Journal of Hydrogen Energy》2009
A two-step thermochemical cycle process for solar hydrogen production from water has been developed using ferrite-based redox systems at moderate temperatures. The cycle offers promising properties concerning thermodynamics and efficiency and produces pure hydrogen without need for product separation. 相似文献
992.
Anja Schwiebs Farha Faqar-Uz-Zaman Martina Herrero San Juan Heinfried H. Radeke 《International journal of molecular sciences》2021,22(11)
Background: Reduction of the Sphingosine-1-phosphate (S1P) degrading enzyme S1P lyase 1 (SGPL1) initiates colorectal cancer progression with parallel loss of colon function in mice. We aimed to investigate the effect of SGPL1 knockout on the stem cell niche in these mice. Methods: We performed immunohistochemical and multi-fluorescence imaging on tissue sections of wildtype and SGPL1 knockout colons under disease conditions. Furthermore, we generated SGPL1 knockout DLD-1 cells (SGPL1−/−M.Ex1) using CRISPR/Cas9 and characterized cell cycle and AKT signaling pathway via Western blot, immunofluorescence, and FACS analysis. Results: SGPL1 knockout mice were absent of anti-Ki-67 staining in the stem cell niche under disease conditions. This was accompanied by an increase of the negative cell cycle regulator FOXO3 and attenuation of CDK2 activity. SGPL1−/−M.Ex1 cells show a similar FOXO3 increase but no arrest of proliferation, although we found a suppression of the PDK1/AKT signaling pathway, a prolonged G1-phase, and reduced stem cell markers. Conclusions: While already established colon cancer cells find escape mechanisms from cell cycle arrest, in vivo SGPL1 knockout in the colon stem cell niche during progression of colorectal cancer can contribute to cell cycle quiescence. Thus, we propose a new function of the S1P lyase 1 in stemness. 相似文献
993.
Carbon materials with different microstructure can be produced by a carbide-derived carbon (CDC) approach varying the carbide precursor and the reaction conditions for the selective etching of the metal. CDC was produced using biomorphic TiC and SiC ceramics derived from paper preforms by a chemical vapor infiltration and reaction technique. In this work the effect of transition metal salt catalysts such as Ru(III), Fe(II), Fe(III) or Ru(III)/Fe(III) on the chlorination process at temperatures in the range 600-1200 °C as well as on the microstructure of the resulting carbon was investigated. The produced CDC was characterized by its degree of order and pore structure using Raman spectroscopy, high resolution transmission electron microscopy and low temperature nitrogen adsorption. A higher etching rate as well as a higher degree of order at lower reaction temperatures was observed if a catalytically active metal was present during the chlorination process. This effect was mostly pronounced in the case of a Ru(III)/Fe(III) bimetallic catalyst. The higher degree of order of the carbon is associated with an increased amount of mesopores and with a decrease in specific surface area. Therefore, the CDC processing in the presence of catalysts offers another way to produce ordered carbon structures at lower temperatures. 相似文献
994.
Characterization of Active Dry Wine Yeast During Starter Culture (Pied de Cuve) Preparation for Sparkling Wine Production 下载免费PDF全文
Ilaria Benucci Katia Liburdi Martina Cerreti Marco Esti 《Journal of food science》2016,81(8):M2015-M2020
The preparation of yeast starter culture (Pied de Cuve) for producing sparkling wine with the traditional method is a key factor for manufacturing a good Prise de mousse. In this paper, the evolution of total yeast population, its viability during Pied de Cuve preparation, and the pressure profile during the 2nd fermentation in 2 different base wines made from Bombino bianco and Chardonnay grapes were investigated using 4 different commercial active dried yeasts. The study proves that despite the initial differences observed throughout the acclimatization phase, all the tested strains showed similar results on either the total population (from 8.2 × 107 cells/mL to 1.3 × 108 cells/mL) or cellular viability (from 70% to 84%). Independently from the base wine tested, the kinetic of sugar consumption was faster during the gradual acclimatization to the alcoholic medium (phase II) and slower during the preparation of starter culture in active growth phase (phase III). During both of these phases Saccharomyces cerevisiae bayanus Vitilevure DV10® (Station ?notechnique de Champagne) proved to have a higher sugar consumption rate than the other strains. During the Prise de mousse, S. cerevisiae bayanus Lalvin EC‐1118® (Lallemand) reached the maximum pressure increase within time in both base wines. 相似文献
995.
Laura Mosca Martina Pagano Luigi Borzacchiello Luigi Mele Annapina Russo Giulia Russo Giovanna Cacciapuoti Marina Porcelli 《International journal of molecular sciences》2021,22(17)
Colorectal cancer (CRC) is the second deadliest cancer worldwide despite significant advances in both diagnosis and therapy. The high incidence of CRC and its poor prognosis, partially attributed to multi-drug resistance and antiapoptotic activity of cancer cells, arouse strong interest in the identification and development of new treatments. S-Adenosylmethionine (AdoMet), a natural compound and a nutritional supplement, is well known for its antiproliferative and proapoptotic effects as well as for its potential in overcoming drug resistance in many kinds of human tumors. Here, we report that AdoMet enhanced the antitumor activity of 5-Fluorouracil (5-FU) in HCT 116p53+/+ and in LoVo CRC cells through the inhibition of autophagy, induced by 5-FU as a cell defense mechanism to escape the drug cytotoxicity. Multiple drug resistance is mainly due to the overexpression of drug efflux pumps, such as P-glycoprotein (P-gp). We demonstrate here that AdoMet was able to revert the 5-FU-induced upregulation of P-gp expression and to decrease levels of acetylated NF-κB, the activated form of NF-κB, the major antiapoptotic factor involved in P-gp-related chemoresistance. Overall, our data show that AdoMet, was able to overcome 5-FU chemoresistance in CRC cells by targeting multiple pathways such as autophagy, P-gp expression, and NF-κB signaling activation and provided important implications for the development of new adjuvant therapies to improve CRC treatment and patient outcomes. 相似文献
996.
Lin Peng Anca Chelariu-Raicu Yao Ye Zhi Ma Huixia Yang Hellen Ishikawa-Ankerhold Martina Rahmeh Sven Mahner Udo Jeschke Viktoria von Schnfeldt 《International journal of molecular sciences》2021,22(17)
Implantation consists of a complex process based on coordinated crosstalk between the endometrium and trophoblast. Furthermore, it is known that the microenvironment of this fetal–maternal interface plays an important role in the development of extravillous trophoblast cells. This is mainly due to the fact that tissues mediate embryonic signaling biologicals, among other molecules, prostaglandins. Prostaglandins influence tissue through several cell processes including differentiation, proliferation, and promotion of maternal immune tolerance. The aim of this study is to investigate the potential pathological mechanism of the prostaglandin E2 receptor 4 (EP4) in modulating extravillous trophoblast cells (EVTs) in unexplained recurrent marriage (uRM). Our results indicated that the expression of EP4 in EVTs was decreased in women experiencing uRM. Furthermore, silencing of EP4 showed an inhibition of the proliferation and induced apoptosis in vitro. In addition, our results demonstrated reductions in β- human chorionic gonadotropin (hCG), progesterone, and interleukin (IL)-6, which is likely a result from the activation of the cyclic adenosine monophosphate (cAMP)- cAMP-dependent protein kinase A (PKA)-phosphorylating CREB (pCREB) pathway. Our data might provide insight into the mechanisms of EP4 linked to trophoblast function. These findings help build a more comprehensive understanding of the effects of EP4 on the trophoblast at the fetal–maternal interface in the first trimester of pregnancy. 相似文献
997.
This article evaluates, by means of multivariate regression, critical factors influencing the collisions of motor vehicles with adult (over 17 years) cyclists that result in fatal injury of cyclists. The analysis is based on the database of the Traffic Police of Czech Republic from the time period 1995–2007. The results suggest that the most consequential categories of factors under study are: inappropriate driving speed of automobile; the head-on crash; and night-time traffic in places without streetlights. The cyclists’ faults are of most serious consequence on crossroads when cyclists deny the right of way. Males are more likely to suffer a fatal injury due to a collision with a car than females. The most vulnerable age group are cyclists above 65 years. A fatal injury of a cyclist is more often driver's fault than cyclist's (598 vs. 370).In order to reduce the fatal risk, it is recommended to separate the road traffic of motor vehicles from bicyclists in critical road-sections; or, at least, to reduce speed limits there. 相似文献
998.
Matteo Ferro Ottavio de Cobelli Mihai Dorin Vartolomei Giuseppe Lucarelli Felice Crocetto Biagio Barone Alessandro Sciarra Francesco Del Giudice Matteo Muto Martina Maggi Giuseppe Carrieri Gian Maria Busetto Ugo Falagario Daniela Terracciano Luigi Cormio Gennaro Musi Octavian Sabin Tataru 《International journal of molecular sciences》2021,22(18)
Radiomics and genomics represent two of the most promising fields of cancer research, designed to improve the risk stratification and disease management of patients with prostate cancer (PCa). Radiomics involves a conversion of imaging derivate quantitative features using manual or automated algorithms, enhancing existing data through mathematical analysis. This could increase the clinical value in PCa management. To extract features from imaging methods such as magnetic resonance imaging (MRI), the empiric nature of the analysis using machine learning and artificial intelligence could help make the best clinical decisions. Genomics information can be explained or decoded by radiomics. The development of methodologies can create more-efficient predictive models and can better characterize the molecular features of PCa. Additionally, the identification of new imaging biomarkers can overcome the known heterogeneity of PCa, by non-invasive radiological assessment of the whole specific organ. In the future, the validation of recent findings, in large, randomized cohorts of PCa patients, can establish the role of radiogenomics. Briefly, we aimed to review the current literature of highly quantitative and qualitative results from well-designed studies for the diagnoses, treatment, and follow-up of prostate cancer, based on radiomics, genomics and radiogenomics research. 相似文献
999.
1000.