BackgroundDistal forearm fractures are common in children. The reference standard to diagnose these fractures is by conventional radiography, which exposes these patients to harmful radiation. Ultrasound (US) seems to be a good alternative. However, emergency physicians (EPs) in the Netherlands have limited experience in using US for diagnosing fractures in children. ObjectiveThe primary objective was to determine the accuracy of US, performed by a Dutch EP, compared with conventional radiography,...
22h
BackgroundAllocation concealment is essential to avoid selection bias in randomised trials. The ACUTE pilot trial compared the effectiveness of pre-hospital CPAP vs standard oxygen therapy for acute respiratory failure (ARF). The randomisation schedule was implemented, and treatment allocation concealed, with a novel method using identical boxes. MethodsInvestigation of allocation concealment in the ACUTE trial proceeded in 4 stages. Firstly, the characteristics of recruited ACUTE trial patients...
22h
Clinical introductionA 3-year-old boy with a reported history of road traffic crash 1 hour ago presented to the ED in an unconscious state. In view of poor GCS (E1V1M1), he was intubated and mechanically ventilated. His circulation was stable. Both pupils were dilated and sluggishly reactive to light. On secondary survey, minor bruises were present on the left side of the face. A provisional diagnosis of severe traumatic brain injury was made and immediate non-contrast computerised tomography head...
22h
BackgroundSupraventricular tachycardia (SVT) is a common heart rhythm disorder. The Valsalva Manoeuvre (VM) is a safe, internationally recommended, initial treatment, but has a low success rate in normal practice. Recent studies have shown much better cardioversion rates, approaching 50%, can be achieved using a postural modification (the modified VM) and a manometer controlled 40 mmHg strain. Successful cardioversion could avoid hospital conveyance and unpleasant treatments, such as adenosine. Routine...
22h
Primary care services in or alongside emergency departments look and function differently and are described using inconsistent terminology. Research to determine effectiveness of these models is hampered by outdated classification systems, limiting the opportunity for data synthesis to draw conclusions and inform decision-making and policy. We used findings from a literature review, a national survey of Type 1 emergency departments in England and Wales, staff interviews, other routine data sources...
22h
BackgroundHead injury results in a high use of emergency services, although most people with head injuries do not require hospitalisation. Conversely, some evidence suggests that lay recognition of the seriousness of head injury can be problematic, for example in sports settings. AimTo investigate how members of the public - parents of young children, school staff, sports coaches, informal carers of older adults, young adults and other adults - understood head injury terminology and when an emergency...
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Best Evidence Topic reports (BETs) summarise the evidence pertaining to particular clinical questions. They are not systematic reviews, but rather contain the best (highest level) evidence that can be practically obtained by busy practising clinicians. The search strategies used to find the best evidence are reported in detail in order to allow clinicians to update searches whenever necessary. Each BET is based on a clinical scenario and ends with a clinical bottom line which indicates, in the light...
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BackgroundContinuous positive airway pressure (CPAP) is not in widespread use in UK ambulance services, but could benefit patients with acute respiratory failure (ARF). As a new treatment in this context, clinician acceptability is an important factor in the feasibility of conducting definitive research in the prehospital arena. MethodsAs part of a pilot randomised controlled trial (the ACUTE study), recruiting clinicians were emailed after enrolling patients to either the CPAP or standard-care...
22h
A shortcut review was carried out to establish whether diclofenac is better than a triptan in treating migraine. 32 papers were found of which only 1 addressed this question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of this paper are tabulated. It is concluded that there is insufficient evidence that either treatment is superior to the other for migraine therapy.
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BackgroundAcute respiratory failure (ARF) is a life-threatening emergency and pre-hospital CPAP may improve outcomes. A CPAP cost-effectiveness determinant is the incidence of eligible patients with ARF. This sub-study of the ACUTE trial aimed to determine the number of adults with ARF potentially suitable for CPAP, presenting to WMAS. MethodsThis observational study was conducted between 1stAugust 2017 and 31st July 2018. Adult patients presenting with SpO2 <94% were identified from WMAS electronic...
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EMJ brought to the attention of emergency physicians the pressing public health issue of human trafficking in its podcast ‘Detecting human trafficking: a life-saving diagnosis in the emergency room’.1 A recent news article in Emergency Medical Service (EMS) World by Amato now highlights the role first responders have in breaking the cycle of human trafficking violence.2 EMS providers can leverage their access to vulnerable populations to identify and advocate for trafficking victims. But it is estimated...
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In this study, we identified LINC00365 was upregulated in colorectal cancer (CRC) and it might promote CRC cell progression via Wnt/β‐catenin signaling pathway. Our study indicated that LINC00365 played a cruial role as an oncogenes and promoted tumor progression, and it might serve as a potential therapeutic target for CRC. Abstract In the past decade, substantial evidence established that long noncoding RNAs are serious about mediating the evolution of malignancies. In previous studies, LINC00365,...
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low‐density lipoprotein receptor‐related protein 6 (LRP6) was lowly expressed in trophoblast cells under hypoxia/reoxygenation (H/R) treatment. LRP6 overexpression enhanced the autophagy flux to strengthen the functions of trophoblast cells. LRP6 overexpression induced autophagy to promote proliferation, migration and invasion of trophoblast cells. Abstract Pre‐eclampsia is a common complication during pregnancy; however, the underlying mechanisms of the crosstalk between low‐density lipoprotein...
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The N‐alkylation of phenylacetamide with benzyl alcohol has been studied using Ni/SiO2‐Al2O3. In the optimized conditions, the desired product was isolated in an excellent 98% yield. The reaction could advantageously be performed in neat conditions, with a slight excess of amide and a catalytic amount of base. These conditions were tested on a large range of amides and alcohols, affording 24 compounds in 13 to 99% isolated yields.
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The symmetrical functionalization at the bay‐positions of terrylene diimides yields near‐infrared absorbing core‐twisted terrylene diimide dyes, which exhibit interesting intermolecular interactions such as short Br···Br and C‐H···O units. Three new symmetrically para‐phenylethynylene‐substituted terrylene diimide derivatives namely, TDI‐Ph, TDI‐PhCN and TDI‐PhNMe2 were synthesized to study the electronic effects on the structure and properties. The solid‐state single‐crystal structures for...
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Tiny amounts of commercially available and easy to handle (Me3P)2NiCl2 trigger the stereoselective aldol addition of chiral N‐2‐pivaloyloxyacetyl thiazolidinethione 7 to acetals to provide the corresponding anti glycolate adducts in a highly efficient manner. The direct and stereocontrolled addition of (S)‐4‐isopropyl‐N‐(2‐pivaloyloxyacetyl)‐1,3‐thiazolidine‐2‐thione to dialkyl acetals of aromatic and α,β‐unsaturated aldehydes catalyzed by 2.5–5 mol‐% of a nickel(II) complex permits the synthesis...
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A simplified access to annelated bicycles based on a Ni(NHC) catalyzed vinylcyclopropane (VCP) rearrangement has been developed. Combined computational and experimental studies unraveled the puzzling reactivity issues, substrate scope and stereoselectivity and delivered a tool for further exploration in the synthesis of complex bicyclic target compounds. The Ni(NHC) catalyzed rearrangement of 1‐acyl‐2‐vinylcyclopropanes to the corresponding 4‐acyl‐cyclopent‐1‐enes is highly promising for the...
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One of the most facile and robust ways of incorporating fluorine atoms in organic substrates is through the Halex fluorination. We have described here the Halex fluorination of β‐chlorovinyl aldehydes using KF/DMSO system under mild conditions. Further the transformation of the fluoro‐substituted intermediates to its dimeric compounds via a cascade sequence of six steps is discussed. Halogen‐exchange (Halex) fluorinations in vinylic systems are rare; under controlled conditions, halex fluorination...
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The Front Cover shows three types of cationic pyridinium‐substituted chlorophyll‐a derivatives with different π‐conjugated cyclic tetrapyrroles (bacteriochlorin, chlorin, and porphyrin). Their photoinduced intramolecular electron transfer from the tetrapyrrole to the pyridinium group depended on their π‐conjugation degrees. The cover image was inspired by a Japanese traditional children's song “Usagi”, which talks about jumping rabbits which are looking at the full moon. People believed in the mystic...
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The Cover Feature shows two gearwheels interlocking, symbolizing the key principle of the cascade reaction. The bottom gearwheel depicts Sonogashira cross‐coupling initiated by a Cu scorpionate to synthesize a 2‐substituted benzofuran derivative. The top gearwheel illustrates the P450 BM3 catalyzed formation to N,N'‐bis(benzofuran‐2‐ylmethyl)‐N,N'‐dimethylmethandiamine. This chemoenzymatic reaction sequence takes advantage of the transition metal catalysis engaged with enzymatic catalysis to synthesize...
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Asymmetric click chemistry is used to induce planar stereogenicity in prochiral ferrocenyl diynes, giving products in up to 99.5 % ee. Asymmetric induction and kinetic resolution studies on a novel library of prochiral 1,2,3‐trisubstituted bis‐alkynylferrocenes are reported. The new asymmetric click CuAAC reaction is used for the first time to induce asymmetry in planar chiral compounds. There are only three classes of stereogenicity (atom‐centred, axial and planar), and these results are therefore...
22h
Access to a series of new porphyrin and bacteriochlorin glycoconjugates, including meso‐glycosylated porphyrins and bacteriochlorins, and beta‐glycosylated porphyrins, using a copper‐catalyzed azide–alkyne 1,3‐dipolar cycloaddition (CuAAC) is reported for the first time. Rapid and reproducible access to a series of unique porphyrin and bacteriochlorin glycoconjugates, including meso‐glycosylated porphyrins and bacteriochlorins, and beta‐glycosylated porphyrins, using copper‐catalyzed azide–alkyne...
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Dirhodium paddlewheel complexes with tethered thioether ligands are evaluated in diazo‐mediated Si–H insertion reactions. The presence of the thioether groups improved yields at elevated temperatures and allowed greater selectivity for diazo compounds compared to non‐thioether tethered catalysts. Computational modelling helped to rationalize the results. The effect of tethering a thioether to a rhodium(II) paddlewheel complex are evaluated in Si–H insertion reactions. This study provides further...
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The Front Cover shows that like in the old French adage, “the best soups are made in the oldest pans” also “the best molecular tools are made with the oldest scaffolds”. A selection of examples in which DOTA‐type macrocycles are used as platforms for building multivalent devices, that found applications in various fields, from materials chemistry to chemical biology, is demonstrated. More information can be found in the https://doi.org/10.1002/ejoc.201900870Minireview by I. E. Valverde, A. Romieu,...
22h
“The challenges are still there and providing answers or helping my students to find these answers is a sweet daily pleasure.” Find out more about this author's research at https://doi.org/10.1002/ejoc.201900547. Abstract “The challenges are still there and providing answers or helping my students to find these answers is a sweet daily pleasure.” Find out more about this author's research at https://doi.org/10.1002/ejoc.201900547.
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The Cover Feature shows a house built in a sugar mountain where a key is driven towards the door lock. The key represents the traditional barbituric acid which site‐selectively reacts with the reducing‐end of protecting group‐free carbohydrates via Knoevenagel condensation. Herein, three sets of N,N'‐disubstituted barbituric acids (mono‐, homo‐bis‐, and hetero‐bis‐functional) have been readily designed allowing the introduction of various functions. This original approach will open the door of opportunity...
22h
No metal, no cry! Macrocyclic polyamines (MPAs) are important chelating agents for cations, anions, and neutral molecules; cyclen and DOTA are well‐known contrast agents for MR or PET/SPECT imaging. Their unique properties also make them attractive multivalent molecular platforms for applications far beyond conventional metal chelation. Their use in materials chemistry, medicinal chemistry, and chemical biology is discussed. Recent advances in the use of radiometals for both imaging and therapy...
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Sugar addict: A convenient and versatile strategy was developed to prepare a series of clickable β‐C‐glycosylbarbiturates or divalent ligands of a lectin via Knoevenagel condensation with readily accessible symmetrical or asymmetrical N,N′‐disubstituted barbituric acids in water. Direct access to non‐hydrolyzable glycoconjugates is highly mandatory for stabilizing their intrinsic biological or physical‐chemistry properties in the surrounding environment. Here, a simple and versatile approach...
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Targeted molecular design of bridged diarylnitroxides with increased kinetic stability of redox forms allowed suggesting new SO2‐locked diarylnitroxide, which was synthesized and fully characterized. It is stable in solution, exhibits the maximal anodic potential value achieved for reversibly oxidized nitroxides to date, and might be of interest as cathodic redox active material. Selection of linkers connecting two phenyl rings as a part of molecular design of diarylnitroxides with increased...
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We report a study on diol cleavage of cyclic 1,2‐dihydroxysilanes for the preparation of functionalized acylsilanes. Sodium periodate is an efficient reagent for this transformation, providing good to excellent yields. The reaction conditions are mild, and in some cases, a simple aqueous workup of the reaction mixture was sufficient to obtain the acylsilanes in high purity. An acyclic 1,2‐dihydroxysilane was readily cleaved as well. We report a study on diol cleavage of cyclic 1,2‐dihydroxysilanes...
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The aldehyde–amine–alkyne (A3) coupling reaction is a powerful multicomponent coupling reaction for the build/couple/pair approach in diversity‐oriented synthesis (DOS), herein demonstrated by the application of Boc‐prolinal for the synthesis of pyrrolidine‐based molecular scaffolds bearing a propargylamine chemical handle. The Aldehyde–Amine–Alkyne reaction (A3) proves to be a powerful methodology as a coupling step of the Build/Couple/Pair approach in Diversity Oriented Synthesis (DOS) because...
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Preparation and synthetic applications of [2.2]paracyclophane trifluoroborates in the Suzuki–Miyaura cross‐coupling reaction is described. The trifluoroborates and halotrifluoroborates described herein are bench‐stable, crystalline solids accessible on multi‐gram scale and can be cross‐coupled with a wide range of aryl(hetero) halides. We report the synthesis of [2.2]paracyclophane (PCP) trifluoroborate building blocks that can be used for the incorporation of the PCP moiety into a wide range...
22h
Series of diquinolinium salts separated by spacers were prepared which possess cationic charges in conjugation and cross‐conjugation as well as combinations thereof. The spectroscopic differences (13C NMR, IR, Raman, UV/Vis) of 2,2‐, 3,3‐, 4,4‐, 3,2‐ and 3,4‐interconnections of positive charges are studied experimentally and by DFT calculations. 1,4‐Diethynylbenzene was used as conjugated all‐carbon and rigid spacer between the 2‐, 3‐ and 4‐positions of two 1‐methylquinolinium rings. Thus,...
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An experimental and computational study into the synthesis of aryl nitriles with nitromethane as an organic and non‐toxic alternative of traditional cyanating sources is presented. The mechanistic pathway of cyanation is the highlight of the current study. Directed by an unusual in situ reduction of CuII, our protocol is a simple CuI‐mediated synthesis of aryl nitriles, with inexpensive and readily available nitromethane as the cyanating source, in moderate to good yields. Exhibiting a wide...
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The reaction mechanisms of nickel‐catalyzed heterodiarylation of alkenes are explored by DFT calculations. The competition of the diarylation against the potential side reactions, such as Heck coupling and Suzuki–Miyaura coupling, is analyzed in great detail. A density functional theory study on nickel‐catalyzed diarylation of styrene (R1) with arylboron (R2) and aryl bromide (R3) is presented in this article, to unveil the plausible mechanism and the competition of the potential side reactions....
22h
Red phosphorus reacts with aryl halides rapidly and exothermically in superbase system to give triarylphosphines in high yields. In one‐pot three consecutive C(SP2)–P bonds were formed through SNAr mechanism. This environmentally friendly, PCl3‐free synthetic method of Ar3P from available starting materials has been developed. Aryl halides, ArX (Ar = Ph, 2‐, 3‐ and 4‐Tol, 1‐ and 2‐Np, 4‐C6H4CONH2; X = F, Cl, Br), rapidly and exothermically (100–180 °C, 0.5–2 h) react with red phosphorus in...
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The synthesis of bis‐enones from alkenyl bromides and α,ω‐bis‐Weinreb amides via a double Grignard reaction is reported. The work contains reliable protocols for the double addition and the efficient generation of the required substituted alkenyl Grignard reagents from alkenyl bromide precursors. An efficient double addition of substituted alkenylmagnesium bromides to bis‐Weinreb amides has been developed, giving α,ω‐bis‐enones that are building blocks for certain drugs and polymers. Furthermore,...
22h
Hypervalent iodine mediates the oxidative olefination of amines with active methylene compounds for the formation of electrophilic alkenes under mild reaction conditions in good to excellent yields. Hypervalent iodine‐mediated oxidative olefination of amines with an active methylene compound provides a rapid gateway towards the formation of electrophilic alkenes under mild reaction conditions in good to excellent yields. This is an efficient protocol for the preparation of substituted electrophilic...
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Synthesis of new cis‐typed bis‐phosphorus cavitands is described, including a description of their catalytic capability in transition‐metal‐catalyzed reactions. The catalysis of cis‐versions were compared to the corresponding trans‐isomeric bis‐phosphorus cavitands, which revealed that different shape of compartments gave different profile of reactivity and product distribution. Three new cis‐diquinoxaline spanned cavitands were successfully synthesized. These cis‐diphosphinated derivatives...
22h
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