Background and Objectives A worldwide pandemic of coronavirus disease 2019 (COVID-19) has affected millions of people. A 'closed-off management' protocol has been launched nationwide in China to cope with this major public health emergency. However, these procedures may cause a crisis for blood donation and blood supply. In this study, we assessed the impact of the COVID-19 pandemic on blood donation and supply in Zhejiang province, which could provide reference and insight for developing countermeasures in other countries. Materials and Methods Blood donor and supply information from 38 blood centres during the Spring Festival of 2019 and 2020 were reviewed. A self-administered questionnaire was carried out. Results Due to the COVID-19 pandemic, the number of whole blood donors dropped by 67%. The success rate of recruitment for donations dropped by 60%. Most respondents (81Á2%) were worried about the 'possibility of acquiring COVID-19 during blood donation'. The total amount of RBCs supply dropped by 65%. In the first week of the outbreak, the weekly amount of issued RBC units (10171Á5 u) was almost six times higher than the collected units (1347Á5 u). The mean haemoglobin value for RBCs transfusion was about 6Á3 g/dl. About 4% of RBCs and 2Á8% of frozen plasma were used in COVID-19 patients. Conclusion The secondary consequences of the COVID-19 pandemic are blood shortages caused by the unavailability of blood donors, and this is likely to be replicated in many countries with high burdens of COVID-19. Practical actions to broaden sources and reduce use for the global crisis must be taken proactively.
Described herein are structure-activity relationship studies that resulted in the optimization of the activity of members of a class of cyclopropyl-fused indolobenzazepine HCV NS5B polymerase inhibitors. Subsequent iterations of analogue design and syntheses successfully addressed off-target activities, most notably human pregnane X receptor (hPXR) transactivation, and led to significant improvements in the physicochemical properties of lead compounds. Those analogues exhibiting improved solubility and membrane permeability were shown to have notably enhanced pharmacokinetic profiles. Additionally, a series of alkyl bridged piperazine carboxamides was identified as being of particular interest, and from which the compound BMS-791325 (2) was found to have distinguishing antiviral, safety, and pharmacokinetic properties that resulted in its selection for clinical evaluation.
Polybinaphthyl zinc catalysts have been developed for the asymmetric epoxidation of alpha,beta-unsaturated ketones in the presence of tert-butyl hydroperoxide. Up to 81% ee has been achieved for the epoxidation of alpha,beta-unsaturated ketones containing beta-aliphatic substituents by using a binaphthyl polymer combined with diethylzinc. A very interesting positive cooperative effect of the catalytic sites in the polymer chain is observed which leads to greatly increased enantioselectivity over the corresponding monomer ligands.
6,6‘-Dibromo-1,1‘-bi-2-naphthol derivatives, where the hydroxyl
groups are protected by alkyl,
methoxymethyl, and acyl groups, have been polymerized using
nickel(0) or nickel(II) complexes as
catalysts. The molecular weights of the resulting polymers have
been analyzed by gel permeation
chromatography and laser light scattering. Hydrolysis of these
polymers has produced the optically
active poly(1,1‘-bi-2-naphthol)s [poly(BINOL)s]. The
poly(BINOL)s are soluble in basic water
solution and have been characterized by NMR, IR, UV, and CD
spectroscopic methods. The reaction
of a (R)-poly(BINOL) with diethylaluminum chloride,
trimethylaluminum, and titanium tetraisopropoxide generates novel polymeric Lewis acid complexes. These
complexes represent a new
generation of polymeric catalysts where the catalytic centers are
highly organized in an optically
active and sterically regular polymer chain. When used to catalyze
the Mukaiyama aldol
condensation, the polymeric aluminum catalyst shows greatly enhanced
catalytic activity over the
monomeric complex.
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