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51.
52.
William R. Nes Antonio Alcaide Frank B. Mallory Josephine R. Landrey Robert L. Conner 《Lipids》1975,10(3):140-144
WhenTetrahymena pyriformis was incubated with sitosterol ([24R]-24-ethylcholest-5-en-3β-ol]) or itstrans-Δ22-derivative (stigmasterol), the C-24-dealkylated product, cholesta-5,7,trans-22-trien-3β-ol, was obtained in both cases. 24(S)-24-Ethylcholesta-5,7,trans-22-trien-3β-ol also was found to be a metabolite. When sitosterol was the substrate, 24(R)-24-ethylcholesta-5,7-dien-3β-ol was obtained as a third product. Identifications were made by mass spectroscopy, quantitative chromatography, labeling with14C, and by other means. The dealkylated product (cholestratrienol) represented 30% of the sterols isolable after incubation. The administration of sterols to this organism did not induce sterol biosynthesis, since 2-14C-mevalonate failed to yield radioactive sterol in the presence of added stigmasterol. 相似文献
53.
Nomie Cresto Camille Gardier Marie-Claude Gaillard Francesco Gubinelli Pauline Roost Daniela Molina Charlne Josephine Noëlle Dufour Gwenaëlle Auregan Martine Guillermier Suva Bernier Caroline Jan Pauline Gipchtein Philippe Hantraye Marie-Christine Chartier-Harlin Gilles Bonvento Nadja Van Camp Jean-Marc Taymans Karine Cambon Graldine Liot Alexis-Pierre Bemelmans Emmanuel Brouillet 《International journal of molecular sciences》2021,22(13)
Alpha-synuclein (α-syn) and leucine-rich repeat kinase 2 (LRRK2) play crucial roles in Parkinson’s disease (PD). They may functionally interact to induce the degeneration of dopaminergic (DA) neurons via mechanisms that are not yet fully understood. We previously showed that the C-terminal portion of LRRK2 (ΔLRRK2) with the G2019S mutation (ΔLRRK2G2019S) was sufficient to induce neurodegeneration of DA neurons in vivo, suggesting that mutated LRRK2 induces neurotoxicity through mechanisms that are (i) independent of the N-terminal domains and (ii) “cell-autonomous”. Here, we explored whether ΔLRRK2G2019S could modify α-syn toxicity through these two mechanisms. We used a co-transduction approach in rats with AAV vectors encoding ΔLRRK2G2019S or its “dead” kinase form, ΔLRRK2DK, and human α-syn with the A53T mutation (AAV-α-synA53T). Behavioral and histological evaluations were performed at 6- and 15-weeks post-injection. Results showed that neither form of ΔLRRK2 alone induced the degeneration of neurons at these post-injection time points. By contrast, injection of AAV-α-synA53T alone resulted in motor signs and degeneration of DA neurons. Co-injection of AAV-α-synA53T with AAV-ΔLRRK2G2019S induced DA neuron degeneration that was significantly higher than that induced by AAV-α-synA53T alone or with AAV-ΔLRRK2DK. Thus, mutated α-syn neurotoxicity can be enhanced by the C-terminal domain of LRRK2G2019 alone, through cell-autonomous mechanisms. 相似文献
54.
An intercrosslinked network of hybrid bismaleimide (BMI) modified vinyl ester oligomer–unsaturated polyester matrix systems have been developed. Vinyl ester oligomer (VEO) was used as a toughening agent for unsaturated polyester resin and was added in 2, 4, and 6% (by wt). Benzoyl peroxide was used as curing agent. The VEO‐toughened unsaturated polyester matrix systems were further modified with 5, 10, and 15% (by wt) of bismaleimide. Bismaleimides modified vinyl ester–unsaturated polyester matrices were characterized by mechanical (tensile strength, flexural strength, tensile modulus, flexural modulus, and impact strength), thermal [differential scanning calorimetry (DSC), thermogravimetic analysis (TGA), heat deflection temperature analysis (HDT)] and morphological studies [scanning electron microscope (SEM)] and water absorption. Data obtained from mechanical studies indicated that the introduction of VEO into unsaturated polyester resin improves the fracture toughness. The introduction of BMI into VEO incorporated unsaturated polyester resin enhanced both thermal and mechanical behavior. The scanning electron micrographs of fractured surfaces of VEO‐modified unsaturated polyester systems and BMI modified vinyl ester–unsaturated polyester matrices illustrate the presence of homogeneous morphology. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 167–177, 2007 相似文献
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Christian Franke Olaf Stenzel Steffen Wilbrandt Mark Schürmann Josephine Wolf Vera Todorova Brenda Doherty Prof. Dr. Norbert Kaiser 《真空研究与实践》2016,28(1):28-32
Determination of the Optical Constants of Common Substrate Materials in the NIR/MIR‐Spectral Regions An approach is reported for determining the optical constants of substrates and single layer coatings in the near and mid‐infrared spectral regions. A combination of the algorithm from Nichelatti and a multi‐oscillator model has been used to determine the optical constants of the substrates. Thus, the approach even works when the sample transmittance is vanishing. We demonstrate the application of the approach to the evaluation of transmission and reflection spectra of common substrates (CaF2, Q1, Sapphire) measured by a Fourier‐Transform‐Infrared spectrophotometer. The comparison of the calculated optical constants with values reported in literature confirms the validity of the used approach. We also demonstrate the IR characterisation of a tantalum oxide single layer deposited onto a Q1 substrate by means of the multi‐oscillator‐model. The results are again in good agreement with literature data. 相似文献
58.
The resilience of small businesses and how that relates to community resilience, especially in rural communities has remained an under‐researched aspect of community resilience. This exploratory study aims to understand the relationship between business resilience and community resilience in rural communities. Firstly, the research seeks to understand the role that small businesses play in contributing to community resilience activities. The paper then sheds light on enabling and challenging factors that shape how small businesses prepare for and respond to weather‐related emergencies through the lens of flooding. Data were collected through in‐depth semi‐structured interviews and surveys with rural small businesses in Scotland. The analysis of the data suggests that businesses play an advisory and advocacy roles, make financial and material contributions to local community resilience activities and contribute to quick community recovery through various dimensions of corporate social responsibility activities. However, small businesses face formidable barriers and challenges in preparing for and responding to weather‐related emergencies that undermine their resilience to natural hazards. The paper suggests ways in which small businesses can enhance their resilience to natural hazards, while at the same time contributing to community resilience. 相似文献
59.
Meera Adishesh Rafah Alnafakh Duncan M. Baird Rhiannon E. Jones Shannon Simon Lucy Button Areege M. Kamal John Kirwan S. Bridget DeCruze Josephine Drury Gabriele Saretzki Dharani K. Hapangama 《International journal of molecular sciences》2020,21(22)
Telomeres are transcribed as long non-coding RNAs called TERRAs (Telomeric repeat containing RNA) that participate in a variety of cellular regulatory functions. High telomerase activity (TA) is associated with endometrial cancer (EC). This study aimed to examine the levels of three TERRAs, transcribed at chromosomes 1q-2q-4q-10q-13q-22q, 16p and 20q in healthy (n = 23) and pathological (n = 24) human endometrium and to examine their association with cellular proliferation, TA and telomere lengths. EC samples demonstrated significantly reduced levels of TERRAs for Chromosome 16p (Ch-16p) (p < 0.002) and Chromosome 20q (Ch-20q) (p = 0.0006), when compared with the postmenopausal samples. No significant correlation was found between TERRA levels and TA but both Ch-16p and Ch-20q TERRA levels negatively correlated with the proliferative marker Ki67 (r = −0.35, p = 0.03 and r = −0.42, p = 0.01 respectively). Evaluation of single telomere length analysis (STELA) at XpYp telomeres demonstrated a significant shortening in EC samples when compared with healthy tissues (p = 0.002). We detected TERRAs in healthy human endometrium and observed altered individual TERRA-specific levels in malignant endometrium. The negative correlation of TERRAs with cellular proliferation along with their significant reduction in EC may suggest a role for TERRAs in carcinogenesis and thus future research should explore TERRAs as potential therapeutic targets in EC. 相似文献
60.
Zhice Zhang Josephine B.M. Goodall David J. Morgan Sonal Brown Robin J.H. Clark Jonathan C. Knowles Nicola J. Mordan Julian R.G. Evans Albert F. Carley Michael Bowker Jawwad A. Darr 《Journal of the European Ceramic Society》2009,29(11):2343-2353
TiO2 doped with various loadings of nitrogen was prepared by nitridation of a nano-TiO2 powder in an ammonia/argon atmosphere at a range of temperatures from 400 to 1100 °C. The nano-TiO2 starting powder was produced in a continuous hydrothermal flow synthesis (CHFS) process involving reaction between a flow of supercritical water and an aqueous solution of a titanium salt. The structures of the resulting nanocatalysts were investigated using powder X-ray diffraction (XRD) and Raman spectroscopy. Products ranging from N-doped anatase TiO2 to phase-pure titanium nitride (TiN) were obtained depending on post-synthesis heat-treatment temperature. The results suggest that TiN started forming when the TiO2 was heat-treated at 800 °C, and that pure phase TiN was obtained at 1000 °C after 5 h nitridation. The amounts and nature of the Ti, O and N at the surface were determined by X-ray photoelectron spectroscopy (XPS). A shift of the band-gap to lower energy and increasing absorption in the visible light region, were observed by increasing the heat-treatment temperature from 400 to 700 °C. 相似文献