Hegelundkelly4579
Vaccines and antiviral agents are in urgent need to stop the COVID-19 pandemic. To facilitate antiviral screening against SARS-CoV-2 without requirement for high biosafety level facility, we developed a bacterial artificial chromosome (BAC)-vectored replicon of SARS-CoV-2, nCoV-SH01 strain, in which secreted Gaussia luciferase (sGluc) was encoded in viral subgenomic mRNA as a reporter gene. The replicon was devoid of structural genes spike (S), membrane (M), and envelope (E). Upon transfection, the replicon RNA replicated in various cell lines, and was sensitive to interferon alpha (IFN-α), remdesivir, but was resistant to hepatitis C virus inhibitors daclatasvir and sofosbuvir. Replication of the replicon was also sensitive overexpression to zinc-finger antiviral protein (ZAP). We also constructed a four-plasmid in-vitro ligation system that is compatible with the BAC system, which makes it easy to introduce desired mutations into the assembly plasmids for in-vitro ligation. This replicon system would be helpful for performing antiviral screening and dissecting virus-host interactions.
Hand grip strength (HGS) has been proposed as a robust predictor for frailty and sarcopenia. Hence, identifying biomarkers for declining HGS accompanying aging could deepen our understanding of the biological underpinnings, informing pre-emptive intervention. Acylcarnitines (ACs) are metabolites generated by fatty acid metabolism in the mitochondria and are dysregulated in multiple disorders affecting the musculature. However, they have not been comprehensively profiled and examined regarding their utility in predicting variability in declining HGS, longitudinally. Thus, we aimed to 1) validate previous findings on insignificant cross-sectional association between ACs and HGS, and 2) examine whether baseline ACs were associated with both decline and variability in HGS over 18 months, in community-dwelling older adults.
We included participants who had HGS measured with dynamometer longitudinally (N = 121). We quantified ACs by targeted plasma metabolomics profiling. Multivariable linear regressions were then performed.
Cross-sectionally, ACs were not significantly associated with HGS. Longitudinally, baseline short-chain dicarboxylic and hydroxylated acylcarnitines (AC-DC/-OH) levels were inversely associated with and significantly explained the variability in 18-month decline in HGS. A specific AC species, the C4-OH, accounted for most of the variance explained.
We showed novel biomarkers for declining HGS, furthering molecular understanding and informing nutritional pre-emptive programs.
We showed novel biomarkers for declining HGS, furthering molecular understanding and informing nutritional pre-emptive programs.There are two major pathways for repairing DNA double-strand breaks (DSBs) homologous directed recombination (HDR) and non-homologous end-joining (NHEJ). While NHEJ functions throughout the cell cycle, HDR is only possible during S/G2 phases, suggesting that there are cell cycle-specific mechanisms regulating the balance between the two repair systems. The regulation exerted by CDKs on HDR has been extensively demonstrated, and here we present evidence that the CDK Pho85, in association with the G1 cyclin Pcl1, phosphorylates Yku80 on Ser 623 to regulate NHEJ activity. Cells bearing a non-phosphorylatable version of Yku80 show increased NHEJ and reduced HDR activity. Accordingly, yku80S623A cells present diminished viability upon treatment with the DSB-producer bleomycin, specifically in the G2 phase of the cell cycle. Interestingly, the mutation of the equivalent residue in human Ku80 increases sensitivity to bleomycin in several cancer cell lines, suggesting that this mechanism is conserved in humans. check details Altogether, our results reveal a new mechanism whereby G1-CDKs mediate the choice between HDR and NHEJ repair pathways, putting the error prone NHEJ on a leash and enabling error free HDR in G2 when homologous sequences are available.Bteich and coworkers recently demonstrated in a companion manuscript (J Pharm Sci 109 https//doi.org/10.1016/j.xphs.2020.07.003) that a protein-mediated hepatic uptake have occurred in an isolated perfused rat liver (IPRL) model for two drugs (Perampanel; PER and Fluoxetine; FLU) that bind extensively to the albumin (ALB) and alpha-1-acid glycoprotein (AGP). However, to our knowledge, there is no quantitative model available to predict the impact of a plasma protein-mediated hepatic uptake on the extent of hepatic clearance (CLh) for a drug binding extensively to these two proteins. Therefore, the main objective was to predict the corresponding CLh, which is an extension of the companion manuscript. The method consisted of extrapolating the intrinsic clearance from the unbound fraction measured in the perfusate or the unbound fraction extrapolated to the surface of the hepatocyte membrane by adapting an existing model of protein-mediated hepatic uptake (i.e., the fup-adjusted model) to include a binding ratio between the ALB and AGP. This new approach showed a relevant improvement compared to the free drug hypothesis particularly for FLU that showed the highest degree of ALB-mediated uptake. Overall, this study is a first step towards the development of predictive methods of CLh by considering the binding to ALB and AGP.Drug controlled release technologies (DCRTs) represent an opportunity for designing new therapies. Main objectives are dose number optimization and secondary effects reduction to improve the level of patient/client acceptance. The present work studies DCRTs based in blended polymeric implants for single dose and long-term therapies of florfenicol (FF), a broad spectrum antibiotic. Polymers used were PLGA and Eudragit E100/S100 types. Eudragit/PLGA and FF/PLGA ratios were the main studied factors in terms of encapsulation efficiencies (EEs) and drug release profiles. In addition, morphological and physicochemical characterization were carried out. EEs were of 50-100% depending on formulation composition, and the FF releasing rate was increased or diminished when E100 or S100 were added, respectively. PLGA hydrolytic cleavage products possibly affect Eudragit solubility and matrix stability. Different mathematical models were used for better understanding and simulating release processes. Implants maintained the antimicrobial activity against Pseudomonas aeruginosa up to 12 days on agar plates.