ABSTRACT
ACE2 is a major receptor for cell entry of SARS-CoV-2. Despite advances in targeting ACE2 to inhibit SARS-CoV-2s binding, how to efficiently and flexibly control ACE2 levels for prevention of SARS-CoV-2 infection has not been explored. Here, we revealed Vitamin C (VitC) administration as an effective strategy to prevent SARS-CoV-2 infection. VitC reduced ACE2 protein levels in a dose-dependent manner, while partial reduction of ACE2 can greatly restrict SARS-CoV-2 infection. Further studies uncovered that USP50 is a crucial regulator of ACE2 protein levels, and VitC blocks the USP50-ACE2 interaction, thus promoting K48-linked polyubiquitination at Lys788 and degradation of ACE2, without disrupting ACE2 transcriptional expression. Importantly, VitC administration reduced host ACE2 and largely blocked SARS-CoV-2 infection in mice. This study identified an in vivo ACE2 balance controlled by both USP50 and an essential nutrient VitC, and revealed a critical role and application of VitC in daily protection from SARS-CoV-2 infection. HighlightsO_LIVitC reduces ACE2 protein levels in a dose-dependent manner C_LIO_LIVitC and USP50 regulate K48-linked ubiquitination at Lys788 of ACE2 C_LIO_LIVitC blocks the interaction between USP50 and ACE2 C_LIO_LIVitC administration lowers host ACE2 and prevents SARS-CoV-2 infection in vivo C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=151 SRC="FIGDIR/small/499651v1_ufig1.gif" ALT="Figure 1"> View larger version (60K): org.highwire.dtl.DTLVardef@196682borg.highwire.dtl.DTLVardef@190f14dorg.highwire.dtl.DTLVardef@d22b59org.highwire.dtl.DTLVardef@1c0faa_HPS_FORMAT_FIGEXP M_FIG C_FIG The deubiquitinase USP50 controls ACE2 protein stability and levels, while Vitamin C blocks the USP50-ACE2 interaction and therefore results in ACE2 degradation, offering a flexible and efficient approach to protection of the host from SARS-CoV-2 infection.
ABSTRACT
Objective: To compare the effects of different purification processes on the content of salidroside in the extract of Herba Rhodiola to provide reference for the large-scale production. Methods: Ethanol precipitation, clarifier precipitation and AB-8 macro-porous resin separation was respectively used to purify the extract of Herba Rhodiolae, and HPLC was used to determine the content of salidroside to screen the optimum purification process. Results: After the purification by AB-8 macroporous resin, the content of sali-droside was as high as 0. 272 5 mg·ml-1followed by that by ethanol precipitation (70% alcohol), and the clarifier precipitation lost more salidroside. Conclusion: The purification of salidroside by AB-8 macroporous resin separation is with high yield, good selectivi-ty, promising reproducibility and so on, which is suitable for the large-scale production of salidroside.
ABSTRACT
Objective To build a performance appraisal system for equipment maintenance departments of hospitals for the purposes of minimal maintenance cost and higher quality of equipments. Methods Literature review and two rounds of expert consultation were carried out in Delphi method. The indicators were classified in such dimensions as technical, economic, efficiency and external evaluation, with the weight of each computed in the proportional distribution method. Results Following expert consultation, adjustment and corrections, an indicator system was finalized consisting of four level-2 indicators and 13 level-2 indicators. Experts came to a consensus, and the W means of both importance and necessity were greater than 0.5. Then an economic calculation plan for equipment maintenance was raised under market-oriented guidance. Conclusions Based on appraisal of the indicator system and economic accounting, an incentive system can be formed for upgrading the repairing and maintenance performance of medical equipments of the hospital.
ABSTRACT
Objective Experiment the effective method to improve cell injury of cerebral ischemia.MethodMake Mongolirn-Gerbil acute full cerebral ischemia model with ligation of double main carotid arteries,observe the influence of intervening abdomen injection of western medicine Nimodipin and TCM Xingnaojing on MDA and SOD in cerebral tissue of Mongolirn-Gerbil in acute period of ischemia reperfusion.ResultIt finds that Nimodipin and Xingnaojing both can markedly increase SOD activity and decrease MDA content,there’s no obvious difference between them,while there’s difference among different dosages of Xingnaojing,the effect is rising with dosage increased.ConclusionAs a Chinese drug of anti-free radical injury,Xingnaojing has similiar effect with Nimodipin.
ABSTRACT
NF-kappaB-repression factor (NRF) is a nuclear inhibitor of NF-kappaB proteins that can silence the IFNbeta promoter. Since NRF was cloned in 1999, in-depth studies have been conducted on the biological functions of this constitutive repressor of NF-kappaB proteins. During large-scale sequencing of a human fetal brain cDNA library we isolated a novel human cDNA that proved to be a correct full-length NRF cDNA. The deduced protein contains 690 aa, and has a G-patch and an R3H domain at its C-terminus. The size of the protein is consistent with its counterparts in mouse and rat. There is considerable evidence that there are some mistakes in the NRF cDNA sequence reported by Nourbakhsh. Here we report the correct, full-length cDNA and protein sequences of NRF. Full-length NRF cDNA is 3247 bp long, contains three exons and maps to human chromosome Xq24. RT-PCR shows that NRF is widely expressed in human tissues.
