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Oxazolidinone substrates, on being subject to hydrogen-transfer reactions through radicals, confirm that sigma-donation causes the anti-stereoselective nature of these reactions in alpha-halo esters. The anti-stereoselectivity is increased by hyperconjungation of a sigma bond with the p-orbital of the radical. The removal of oxazolidinone heteroatoms or endocyclic substitution results in a change in the electronic nature of the C4-C5 bond, further substantiating the part played by sigma-donation in regulating the facial selectivity in hydrogen-transfer reactions.

Background: In nutrition research, randomised controlled trials (RCTs) and cohort studies provide complementary evidence. This meta-epidemiological study aims to evaluate the agreement of effect estimates from individual nutrition RCTs and cohort studies investigating a highly similar research question and to investigate determinants of disagreement., Methods: MEDLINE, Epistemonikos, and the Cochrane Database of Systematic Reviews were searched from January 2010 to September 2021. We matched individual RCTs to cohort studies based on population, intervention/exposure, comparator, and outcome (PI/ECO) characteristics. Two reviewers independently extracted study characteristics and effect estimates and rated the risk of bias using RoB2 and ROBINS-E. Agreement of matched RCTs/cohort studies was analysed by pooling ratio of risk ratios (RRR) and difference of (standardised) mean differences (DSMD)., Results: We included 64 RCT/cohort study pairs with 4,136,837 participants. Regarding PI/ECO similarity, 20.3% pairs were "more or less identical", 71.9% "similar but not identical" and 7.8% "broadly similar". Most RCTs were classified as "low risk of bias" (26.6%) or with "some concerns" (65.6%); cohort studies were mostly rated with "some concerns" (46.6%) or "high risk of bias" (47.9%), driven by inadequate control of important confounding factors. Effect estimates across RCTs and cohort studies were in high agreement (RRR 1.00 (95% CI 0.91-1.10, n = 54); and DSMD - 0.26 (95% CI - 0.87-0.35, n = 7)). In meta-regression analyses exploring determinants of disagreements, risk-of-bias judgements tend to have had more influence on the effect estimate than "PI/ECO similarity" degree., Conclusions: Effect estimates of nutrition RCTs and cohort studies were generally similar. Careful consideration and evaluation of PI/ECO characteristics and risk of bias is crucial for a trustworthy utilisation of evidence from RCTs and cohort studies., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Objectives: Numerous systematic reviews (SRs) have been published in the first months of the COVID-19 pandemic and clinical trials were designed rapidly highlighting the importance of informative implications for research (IfRs) sections in SRs. IfR is one item of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 checklist and the Cochrane Handbook suggests considering population, intervention, control, outcome (PICO) and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) domains when developing IfR. We aimed (1) to assess whether SRs on COVID-19 treatments included any IfR statements and, for SRs with an IfR statement, (2) to examine which elements informed the IfR statement., Study Design and Setting: We conducted a metaresearch study based on SRs on COVID-19 treatment identified in the Living OVerview of the Evidence COVID-19 database in May 2021 as part of another research project (CRD42021240423). We defined an IfR statement as at least one sentence that contained at least one bit of information that could be informative for planning future research. We extracted any IfR statements anywhere in the SRs on predefined IfR variables, in particular PICO elements, study design, and concepts underlying GRADE domains. Three authors extracted data independently after piloting the data extraction form. We resolved discrepancies in weekly discussions to ensure a high-quality data extraction., Results: We included 326 SRs, of which 284 SRs (87.1%) stated IfR. Of these 284 SRs, 201 (70.8%) reported using Preferred Reporting Items for Systematic Reviews and Meta-Analyses and 66 (23.2%) using GRADE. IfR statements (n = 284) addressing PICO were unstructured and commonly reported 'population' (n = 195, 68.7%), 'intervention' (n = 242, 85.2%), and 'outcome' (n = 127, 44.7%) but not 'control' (n = 29, 10.2%). Concepts underlying GRADE domains were infrequently reported in IfR statements of SRs (n = 284): 'risk of bias' (n = 14, 4.9%), 'imprecision' (n = 8, 2.8%), 'inconsistency' (n = 7, 2.5%), 'publication bias' (n = 3, 1.1%), and 'indirectness' (n = 1, 0.4%). Additional IfR elements mentioned in IfR were 'better reporting' of future studies (n = 17, 6.0%) and 'standardization of procedures in clinical trials' (n = 12, 4.2%)., Conclusion: Almost 90% of SRs on COVID-19 treatments reported IfR. IfR statements addressing PICO were unstructured across SRs and concepts underlying GRADE were rarely reported to inform IfR. Further work is needed to assess generalizability beyond COVID-19 and to define more precisely which IfR elements should be considered, and how they should be reported in SRs of interventions. Until then, considering PICO elements and concepts underlying GRADE to derive IfR seems to be a sensible starting point., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

A new series of non-peptidic renin inhibitors having a 2-substituted butanediamide moiety at the P2 and P3 positions has been identified. The optimized inhibitors have IC50 values of 0.8 to 1.4 nM and 2.5 to 7.6 nM in plasma renin assays at pH 6.0 and 7.4, respectively. When evaluated in the normotensive cynomolgus monkey model, two of the most potent inhibitors were orally active at a dose as low as 3 mg/kg. These potent renin inhibitors are characterized by oral bioavailabilities of 40 and 89% in the cynomolgus monkey. Inhibitor 3z (BILA 2157 BS) was selected as candidate for pre-development.

Novel arylpiperazines were identified as alpha 1-adrenoceptor (AR) subtype-selective antagonists by functional in vitro screening. 3-[4-(ortho-Substituted phenyl)piperazin-1-yl]propylamines were derivatized with N,N-dimethyl anthranilamides, nicotinamides, as well as carboxamides of quinoline, 1,8-naphthyridine, pyrazolo[3,4-b]pyridine, isoxazolo[3,4-b]pyridine, imidazo[4,5-b]pyridine, and pyrazolo[1,5-a]pyrimidines. Strips of rabbit bladder neck were employed as a predictive assay for antagonism in the human lower tract. Rings of rat aorta were used as a "negative screen" for the test antagonists. Binding to alpha 1-ARs was relatively sensitive to size and electronic features of the arylpiperazine portion of the antagonists and permissive to these features on the heteroaryl carboxamide side. These structure-affinity findings were exploited to produce nicotinamides (e.g. 13ii and 25x) and pyrazolo[3,4-b]pyridines (e.g. 37f and 37y) ligands with nanomolar affinity at the alpha 1-AR subtype prevalent in the human lower urinary tract(pA2 values: 8.8, 10.7, 9.3, and 9.9, respectively) and displaying 2-3 orders of magnitude selectivity over the alpha 1D-AR.

The D to I conversion of glycogen synthase from human polymorphonuclear leukocytes was examined both in a gel-filtered homogenate and in a preparation of glycogen particles with adhering enzymes, purified by chromatography on concanavalin A bound to Sepharose. It was found that glucose 6-phosphate as well as mannose 6-phosphate, glucosamine 6-phosphate, and 2-deoxy-glucose 6-phosphate activated the reaction, whereas the corresponding sugars were without effect. Mn2+ and Ca2+ increased the conversion rate by 51% and 27%, respectively, whereas Mg2+ and inorganic phosphate were without effect. Sodium fluoride inhibited the reaction completely. Glycogen inhibited the reaction in physiological concentrations and 0.5 mM glucose 6-phosphate was able to overcome this inhibition. MgATP greatly augmented the inhibition caused by glycogen in the glycogen particle preparation. This combined effect could be overcome by glucose 6-phosphate in concentrations from 0.1 to 1 mM. Phosphorylase alpha purified from human polymorphonuclear leukocytes inhibited the D to I conversion in a glycogen particle preparation. The inhibition was counteracted by glucose 6-phosphate and to a lesser degree by AMP. Phosphorylase beta was also inhibitory, but only at higher concentrations than phosphorylase alpha. No phosphorylase phosphatase activity was found in the glycogen particle preparation, which may indicate that chromatography on concanavalin A-Sepharose separates this enzyme from the synthase phosphatase or partially destroys the activity of a hypothetical common protein phosphatase.