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Network meta-analysis compares multiple treatments in terms of their efficacy and harm by including evidence from randomized controlled trials. Most clinical trials use parallel design, where patients are randomly allocated to different treatments and receive only 1 treatment. However, some trials use within person designs such as split-body, split-mouth, and crossover designs, where each patient may receive more than one treatment. Data from treatment arms within these trials are no longer independent, so the correlations between dependent arms need to be accounted for within the statistical analyses. Ignoring these correlations may result in incorrect conclusions. The main objective of this study is to develop statistical approaches to adjusting weights for dependent arms within special design trials. In this study, we demonstrate the following 3 approaches: the data augmentation approach, the adjusting variance approach, and the reducing weight approach. These 3 methods could be perfectly applied in current statistical tools such as R and STATA. An example of periodontal regeneration was used to demonstrate how these approaches could be undertaken and implemented within statistical software packages and to compare results from different approaches. The adjusting variance approach can be implemented within the network package in STATA, while reducing weight approach requires computer software programming to set up the within-study variance-covariance matrix.

Herein we report the first method for highly enantioselective Brønsted acid catalyzed Heyns rearrangements. These reactions, catalyzed by a chiral spiro phosphoric acid, afforded synthetically valuable chiral α‐aryl‐α‐aminoketones which cannot be obtained by means of previously reported Heyns rearrangement methods. This method features low catalyst loadings, high yields and high enantioselectivities, making these reactions highly practical. We used the method to efficiently synthesize various chiral amines, including some biologically active molecules. We experimentally proved that these acid‐catalyzed Heyns rearrangements proceeded via a proton‐transfer process involving an enol intermediate and the stereocontrol was realized during the proton‐transfer step. [ABSTRACT FROM AUTHOR]

In the world of elite sport, pain and suffering are inherent. In exploring return-to-play treatments and decision-making in sports medicine, two overarching areas seem to dominate the existing literature: (i) the autonomy of the injured athlete and (ii) the conflicts of interests faced by the sport medical practitioner. Today, these two ethical issues are further exacerbated by innovations in biomedical technologies. An in-depth analysis will be conducted on how novel and emerging biomedical technologies in modern sports medicine affect—and further perpetuate—the pre-existing bioethical issues, using the case study of platelet-rich plasma therapy used by elite athletes. Attitudes towards novel technologies will be further explored, comparing both the faith-like commitments and the rejection of novel technologies with areas in religious epistemology. A pluralistic approach to clinical practice will be suggested, to begin resolving some of the bioethical issues present. [ABSTRACT FROM AUTHOR]

Background: Obstructive sleep apnoea (OSA) affects many children, and adenotonsillar hypertrophy is the most common cause of paediatric OSA. Aim: Despite the growing treatment options, there is no comprehensive comparison of all interventions. We aimed to compare and rank the effectiveness of various treatments in a network meta‐analysis. Design: Literature was searched from inception to 13 May 2018 for paediatric OSA with adenotonsillar hypertrophy. The outcomes were the changes in apnoea‐hypopnea index (AHI), oxyhaemoglobin desaturation index (ODI), and lowest arterial oxygen saturation (SaO2). Frequentist approach to network meta‐analysis was used. Treatment hierarchy was summarized according to the surfaces under the cumulative ranking curves. Results: Fourteen trials comprising 1064 paediatric OSA participants evaluating ten interventions (adenotonsillectomy, adenotonsillectomy + pharyngoplasty, adenotonsillotomy, antimicrobial therapy, steroids, leukotriene receptor antagonists [LTRAs], steroids + LTRAs, rapid maxillary expansion [RME], placebo, and no treatment) were identified for network meta‐analysis. In terms of effectiveness in AHI reduction, surgical approach was still the most effective intervention than no treatment. RME was one of the most effective interventions to improve lowest SaO2. No comparisons showed statistical significance in reducing ODI. Conclusions: Irrespective of the intervention used, complete resolution of OSA was not achieved in most trials. [ABSTRACT FROM AUTHOR]

Organozinc reagents are among the most commonly used organometallic reagents in modern synthetic chemistry, and multifunctionalized organozinc reagents can be synthesized from structurally simple, readily available ones by means of alkyne carbozincation. However, this method suffers from poor tolerance for terminal alkynes, and transformation of the newly introduced organic groups is difficult, which limits its applications. Herein, we report a method for vinylzincation of terminal alkynes catalyzed by newly developed iron catalysts bearing 1,10-phenanthroline-imine ligands. This method provides efficient access to novel organozinc reagents with a diverse array of structures and functional groups from readily available vinylzinc reagents and terminal alkynes. The method features excellent functional group tolerance (tolerated functional groups include amino, amide, cyano, ester, hydroxyl, sulfonyl, acetal, phosphono, pyridyl), a good substrate scope (suitable terminal alkynes include aryl, alkenyl, and alkyl acetylenes bearing various functional groups), and high chemoselectivity, regioselectivity, and stereoselectivity. The method could significantly improve the synthetic efficiency of various important bioactive molecules, including vitamin A. Mechanistic studies indicate that the new iron-1,10-phenanthroline-imine catalysts developed in this study have an extremely crowded reaction pocket, which promotes efficient transfer of the vinyl group to the alkynes, disfavors substitution reactions between the zinc reagent and the terminal C-H bond of the alkynes, and prevents the further reactions of the products. Our findings show that iron catalysts can be superior to other metal catalysts in terms of activity, chemoselectivity, regioselectivity, and stereoselectivity when suitable ligands are used.

The scarcity of reliable methods for synthesizing chiral gem-diarylmethine borons limits their applications. Herein, we report a method for highly enantioselective dirhodium-catalyzed B-H bond insertion reactions with diaryl diazomethanes as carbene precursors. These reactions afforded chiral gem-diarylmethine borane compounds in high yield (up to 99 % yield), high activity (turnover numbers up to 14 300), high enantioselectivity (up to 99 % ee) and showed unprecedented broad functional group tolerance. The borane compounds synthesized by this method could be efficiently transformed into diaryl methanol, diaryl methyl amine, and triaryl methane derivatives with good stereospecificity. Mechanistic studies suggested that the borane adduct coordinated to the rhodium catalyst and thus interfered with decomposition of the diazomethane, and that insertion of a rhodium carbene (generated from the diaryl diazomethane) into the B-H bond was most likely the rate-determining step., (© 2021 Wiley-VCH GmbH.)

Objective: To compare clinical effect of cannulated screw and bone plate for the treatment of humeral fracture of greater tuberosity., Methods: From January 2010 to January 2020, clinical trial literatures on the treatment of humeral tuberosity fractures with cannulated screw and bone plate were searched by PubMed, EMbase, Cochrane Library, Wanfang, CNKI, CBM Database, VIP Database and other databases. Independent literature screening, quality evaluation, and data extraction were performed according to inclusion and exclusion criteria. Revman5.2 software was used to perform Meta analysis., Results: Totally 5 clinical randomized controlled trials and 12 cohort studies were selected, including 1 068 patientsin which 559 patients were treated by cannulated screw internal fixation and 509 patients treated by bone plate internal fixation. Meta analysis resluts showed that there were satistical differences in operation time[MD=-23.03, 95% CI(-29.69, -16.36), P <0.000 1], blood loss[MD=-36.39, 95% CI(-53.73, -19.04), P <0.000 1], hospital stay[MD=-1.86, 95%CI(-3.09, -0.64), P =0.003], fracture healing time [MD=-2.23, 95% CI (-4.27, -0.18), P =0.03], postoperative incidence of infection [ OR =0.17, 95%CI (0.03, 0.97), P =0.05], failure rate of internal fixation [ OR =3.56, 95% CI (1.29, 9.81), P =0.01] bwteen two groups. While there were no differences in postoperative visual analogue scale (VAS)[MD=-1.34, 95% CI (-2.77, 0.09), P =0.07], American Shoulder and Elbow Surgeons(ASES)[MD=0.26, 95% CI(-6.43, 6.96), P =0.94], Constant shoulder score [MD=-4.05, 95% CI(-8.51, 0.42), P =0.08], excellent rate of Constant shoulder score[MD=-1.30, 95% CI(0.46, 3.72), P =0.62], excellent rate of Neer shoulder joint score[ OR =2.04, 95% CI(0.97, 4.28), P =0.06], total complication rate[ OR =1.50, 95% CI (0.42, 5.35), P =0.53], incidence of postoperative pain[ OR =0.74, 95% CI(0.04, 14.49), P =0.84] and incidence of postoperative acromion syndrome [ OR =0.88, 95% CI (0.02, 40.63), P =0.95] between two groups., Conclusion: Compared with bone plate, cannulated screw for the treatment of humeral fracture of greater tuberosity has advantages of shorter opertaion time, less blood loss, shorter hospital stay, lower incidence rate of postopertaive infection, and more benefit for fracture healing.

In current scenario,the soil pollution has become very severe and its effects on agricultural and ecological security issues cannot be ignored as various contaminants are discharged into soil.Thus,the soil pollution is exigent and has to be solved.This research took soil resistance (Rt),resilience (Rl) and stability (Sb) as evaluation indexes for judging soil quality by exerting different concentration (concentration ratio) gradient of pyrene (PYR),cadmium (Cd) and pyrene/cadmium (PYR/Cd) combined pollutants.A sympathetic description was showed from the aspects of microbial activity,diversity and abundance of soil ecosystem,and the models were constructed to describe the dose-response relationship between PYR-Sb and Cd-Rt.The research showed that different types of pollutants had certain inhibition on soil DOC content.In Cd and PYR simplex pollution,soil microbial mean biomass and colony number decreased with increasing concentration of pollutants.In PYR/Cd combined pollution,the ratio of PYR and Cd had a negative correlation with the decreasing rate of DOC and resistance,meanwhile Cd had a prominent influence on the above-mentioned correlations,in other words,the soil with higher concentration of Cd had lower DOC decrease rate and resistance,and Cd would have dominant inhibition effect on microorganisms under PYR/Cd combined pollution.In addition,this study found the significant correlation of c PYR -Sb and c Cd -Rt,and built the binomial forecasting model to describe the dose-response relationship of c PYR -Sb and c Cd -Rt.