The WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group IMPORTANCE Clinical trials assessing the efficacy of IL-6 antagonists in patients hospitalized for COVID-19 have variously reported benefit, no effect, and harm.OBJECTIVE To estimate the association between administration of IL-6 antagonists compared with usual care or placebo and 28-day all-cause mortality and other outcomes.DATA SOURCES Trials were identified through systematic searches of electronic databases between October 2020 and January 2021. Searches were not restricted by trial status or language. Additional trials were identified through contact with experts.STUDY SELECTION Eligible trials randomly assigned patients hospitalized for COVID-19 to a group in whom IL-6 antagonists were administered and to a group in whom neither IL-6 antagonists nor any other immunomodulators except corticosteroids were administered. Among 72 potentially eligible trials, 27 (37.5%) met study selection criteria. DATA EXTRACTION AND SYNTHESISIn this prospective meta-analysis, risk of bias was assessed using the Cochrane Risk of Bias Assessment Tool. Inconsistency among trial results was assessed using the I 2 statistic. The primary analysis was an inverse variance-weighted fixed-effects meta-analysis of odds ratios (ORs) for 28-day all-cause mortality. MAIN OUTCOMES AND MEASURESThe primary outcome measure was all-cause mortality at 28 days after randomization. There were 9 secondary outcomes including progression to invasive mechanical ventilation or death and risk of secondary infection by 28 days.RESULTS A total of 10 930 patients (median age, 61 years [range of medians, 52-68 years]; 3560 [33%] were women) participating in 27 trials were included. By 28 days, there were 1407 deaths among 6449 patients randomized to IL-6 antagonists and 1158 deaths among 4481 patients randomized to usual care or placebo (summary OR, 0.86 [95% CI, 0.79-0.95]; P = .003 based on a fixed-effects meta-analysis). This corresponds to an absolute mortality risk of 22% for IL-6 antagonists compared with an assumed mortality risk of 25% for usual care or placebo. The corresponding summary ORs were 0.83 (95% CI, 0.74-0.92; P < .001) for tocilizumab and 1.08 (95% CI, 0.86-1.36; P = .52) for sarilumab. The summary ORs for the association with mortality compared with usual care or placebo in those receiving corticosteroids were 0.77 (95% CI, 0.68-0.87) for tocilizumab and 0.92 (95% CI, 0.61-1.38) for sarilumab. The ORs for the association with progression to invasive mechanical ventilation or death, compared with usual care or placebo, were 0.77 (95% CI, 0.70-0.85) for all IL-6 antagonists, 0.74 (95% CI, 0.66-0.82) for tocilizumab, and 1.00 (95% CI, 0.74-1.34) for sarilumab. Secondary infections by 28 days occurred in 21.9% of patients treated with IL-6 antagonists vs 17.6% of patients treated with usual care or placebo (OR accounting for trial sample sizes, 0.99; 95% CI, 0.85-1.16). CONCLUSIONS AND RELEVANCEIn this prospective meta-analysis of clinical trials of patients hosp...

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We have evaluated the effect of NaCl concentration on the mode of binding of poly-L-lysine to DNA and the resulting structural and functional features of the condensed DNA particles using DNA precipitation, DNase I resistance, electron microscopy, and receptor-mediated gene transfer assays. At a high concentration of NaCl and in the presence of excess DNA, poly-L-lysine interacted with DNA cooperatively, fully condensing some of the DNA and leaving the rest of the DNA unbound. At low NaCl concentrations, poly-L-lysine molecules interacted with DNA in a noncooperative fashion, i.e. they bind randomly to the whole population of DNA molecules. Cooperative binding of poly-L-lysine to DNA occurred over a narrow range of NaCl concentrations, and the specific salt concentration depended on the length of the poly-L-lysine. The ability of condensed DNA to withstand digestion by DNase I was correlated with the structural features of the condensed DNA as determined by electron microscopy. Using our condensation procedure, cooperative binding of poly-L-lysine to DNA is a necessary prerequisite for the preparation of condensed DNA having a spherical shape and a diameter of 15-30 nm. Condensed DNA, containing galactosylated poly-Llysine, was evaluated further for the extent and specificity of receptor-mediated gene transfer into HuH-7 human hepatoma cells via the asialoglycoprotein receptor. Efficient receptor-mediated transfection occurred only when condensed DNA complexes had a spherical shape with a diameter of 15-30 nm; asialofetuin, a natural ligand for the asialoglycoprotein receptor, inhibited this process by up to 90%. Our results support the importance of appropriate DNA condensation for the uptake and ultimate expression of DNA in hepatic cells.The concept of receptor-mediated gene transfer originated from the work of Cheng et al. (1), who covalently attached a ligand to DNA. This idea was modified and used more widely for gene delivery by Wu and Wu (2, 3). They introduced poly-L-lysine into the gene transfer system to act as a "bridge" between the DNA and the ligand. After intravenous injection of ligand⅐poly-L-lysine⅐DNA complexes targeting the asialoglycoprotein receptor, the transgene was delivered specifically to the liver, in which it expressed transiently. Because receptor-mediated endocytosis is a general cellular mechanism, it can be applied to other specifically localized receptors (4). Since then, several groups have reported similar receptor-mediated gene delivery systems using ligand⅐poly-L-lysine⅐DNA complexes to introduce various genes to specific tissues by using different targeting ligands (5-15).It was proposed that poly-L-lysine has the dual function of condensing DNA after electrostatic binding and providing the attachment site for the liver-targeting ligand (16). Condensation of the DNA into small particles is a crucial step for successful gene transfer. The process of DNA condensation has been examined widely (17-28). For example, if electrostatic interactions between poly-L-lysine and the DNA ...

Aims/hypothesis The endocannabinoid system has a key role in energy storage and metabolic disorders. The endocannabinoid receptor 2 (CB2R), which was first detected in immune cells, is present in the main peripheral organs responsible for metabolic control. During obesity, CB2R is involved in the development of adipose tissue inflammation and fatty liver. We examined the long-term effects of CB2R deficiency in glucose metabolism. Methods Mice deficient in CB2R (Cb2 −/− [also known as Cnr2]) were studied at different ages (2-12 months). Twomonth-old Cb2 −/− and wild-type mice were treated with a selective CB2R antagonist or fed a high-fat diet.Results The lack of CB2R in Cb2 −/− mice led to greater increases in food intake and body weight with age than in Cb2 +/+ mice. However, 12-month-old obese Cb2 −/− mice did not develop insulin resistance and showed enhanced insulin-stimulated glucose uptake in skeletal muscle. In agreement, adipose tissue hypertrophy was not associated with inflammation. Similarly, treatment of wild-type mice with CB2R antagonist resulted in improved insulin sensitivity. Moreover, when 2-month-old Cb2 −/− mice were fed a high-fat diet, reduced body weight gain and normal insulin sensitivity were observed. Conclusions/interpretation These results indicate that the lack of CB2R-mediated responses protected mice from both age-related and diet-induced insulin resistance, suggesting that these receptors may be a potential therapeutic target in obesity and insulin resistance.