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1.
Lissy Z. F. Gross Mariana Sacerdoti Prof. Albrecht Piiper Prof. Stefan Zeuzem Dr. Alejandro E. Leroux Dr. Ricardo M. Biondi 《ChemMedChem》2020,15(18):1682-1690
Angiotensin converting enzyme 2 (ACE2) is the human receptor that interacts with the spike protein of coronaviruses, including the one that produced the 2020 coronavirus pandemic (COVID-19). Thus, ACE2 is a potential target for drugs that disrupt the interaction of human cells with SARS-CoV-2 to abolish infection. There is also interest in drugs that inhibit or activate ACE2, that is, for cardiovascular disorders or colitis. Compounds binding at alternative sites could allosterically affect the interaction with the spike protein. Herein, we review biochemical, chemical biology, and structural information on ACE2, including the recent cryoEM structures of full-length ACE2. We conclude that ACE2 is very dynamic and that allosteric drugs could be developed to target ACE2. At the time of the 2020 pandemic, we suggest that available ACE2 inhibitors or activators in advanced development should be tested for their ability to allosterically displace the interaction between ACE2 and the spike protein. 相似文献
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Christian P. Romero Jonathan I. Avila Edgardo Cisternas Guerau B. Cabrera Alejandro L. Cabrera Kristiaan Temst Margriet J. Van Bael 《Journal of Materials Science》2007,42(18):7667-7672
Hydrogen desorption curves were obtained from a sample composed of a square arrangement of Co dots with average diameter of
4.4 μm, separated by a distance of 11.6 μm. A macroscopic sample of Co dots grown on a 2.5 × 2.5 cm Si substrate was made
by standard lithographic techniques and used in these experiments. Thermal programmed desorption (TPD) was performed under
ultra-high vacuum conditions. Hydrogen TPD curves were obtained from a 1 × 1 cm Co dots samples displaying a maximum of intensity
at 425 K. Hydrogen TPD curve was also obtained from 1 cm× 1 cm samples of Co films and Co foils for comparison. The hydrogen
TPD curves have decreasing intensity from the Co foils to the Co dots and finally to the Co films. This indicates that there
are more sites for hydrogen adsorption on the Co dots than in the Co films. This is a surprising result because there is approximately
8.7 times less Co atoms exposed in the Co dots that in the Co film sample. A desorption energy of 27 kcal/mol was obtained
for the Co dots suggesting that hydrogen is adsorbed on an hcp hollow site of the Co dot crystalline structure. 相似文献
5.
Reid D.T. McGowan C. Ebrahimzadeh M. Sibbett W. 《Quantum Electronics, IEEE Journal of》1997,33(1):1-9
We describe the design and operation of a critically phase-matched femtosecond optical parametric oscillator based on KTA. By employing a small pump-signal noncollinear angle, tuning of the idler to beyond 4 μm is achieved using a Ti:sapphire pump laser. A Gaussian-beam model is described which can be used to identify the optimal noncollinear phase-matching geometry. Idler and signal pulses are characterized fully both temporally and spectrally and interferometric autocorrelation data at 3.5 μm showing idler pulses of only eight optical cycles duration are presented 相似文献
6.
This paper shows a few possibilities for the application of Community OR in a Third World country based on experience in Venezuela. These possibilities are discussed in a framework of the relationship between the state and community organizations. Emphasis lies in showing that Community OR in Venezuela requires a deep critical commitment to emancipation in order to help community organizations develop in a rather hostile environment. Lastly, results in dealing with community organizations in Venezuela using the Interpretive Systemology approach are presented. 相似文献
7.
CJ Reid 《Canadian Metallurgical Quarterly》1993,7(3):327-328
The results of a retrospective study of routine measurement of haemoglobin at the examination of one-year-old children at Gr?land mother and child clinic during 1989-91 showed that 37% of the children had anaemia. There was no difference between immigrants and the European population. There was no correlation between anaemia and sex in either of the population groups. This may imply that routine haemoglobin measurement should be generally introduced as part of the regular control of one-year-old children. 相似文献
8.
The qualitative and quantitative occurrence and fate of dissolved organic carbon (DOC) leaching into coal slurry transport water was examined in laboratory-generated coal slurries and wastewaters from the Black Mesa coal slurry pipeline. Laboratory slurries were formulated for both western coals (Wyodak, Montana Rosebud and Black Mesa) and eastern coals (Illinois No. 6 and Pittsburgh No. 8). Sephadex G-25 elution profiles and ultrafiltration studies indicate that the majority of the organic compounds in western coal slurry wastewaters were lower (less than 1000) molecular weight species (62% for Wyodak and 74% for Montana Rosebud). Biochemical Oxygen Demand (BOD) for these particular wastewaters ranged from 50 to 150 mg l−1 as determined through the use of an electrolytic respirometer. Also, there was a concomitant 51–74% reduction in the DOC levels in the wastewaters. This removal was primarily due to the removal of the lower (< 1000) molecular weight compounds by the seed inoculum. There was no evidence for the presence of mutagenic organics in the raw wastewater. 相似文献
9.
Differentiation of apple juice samples on the basis of heat treatment and variety using chemometric analysis of MIR and NIR data 总被引:4,自引:0,他引:4
Linda M. Reid Tony Woodcock Colm P. ODonnell J. Daniel Kelly Gerard Downey 《Food research international (Ottawa, Ont.)》2005,38(10):1109-1115
The potential of mid-infrared (MIR) and near-infrared (NIR) spectroscopy for their ability to differentiate between apple juice samples on the basis of apple variety and applied heat-treatment was evaluated. The heat-treatment involved exposure of juice samples (15 ml) for 30 s in a 900 W microwave oven and the apple varieties used to produce the juice samples were Bramley, Elstar, Golden Delicious and Jonagold. The chemometric procedures applied to the MIR and NIR data were partial least squares regression (PLS1 for differentiation on the basis of heat-treatment, PLS2 for varietal differentiation) and linear discriminant analysis (LDA) applied to principal component (PC) scores. PLS1 and PLS2 gave the highest level of correct classification of the apple juice samples according to heat-treatment (77.2% for both MIR and NIR data) and variety (78.3–100% for MIR data; 82.4–100% for NIR data), respectively. 相似文献
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