We aimed to assess the impact of timing of surgery in elderly patients with acute hip fracture on morbidity and mortality. We systematically searched MEDLINE, the Cochrane Library, Embase, PubMed, ...and trial registries from 01/1997 to 05/2017, as well as reference lists of relevant reviews, archives of orthopaedic conferences, and contacted experts. Eligible studies had to be randomised controlled trials (RCTs) or prospective cohort studies, including patients 60 years or older with acute hip fracture. Two authors independently assessed study eligibility, abstracted data, and critically appraised study quality. We conducted meta-analyses using the generic inverse variance model. We included 28 prospective observational studies reporting data of 31,242 patients. Patients operated on within 48 hours had a 20% lower risk of dying within 12 months (risk ratio (RR) 0.80, 95% confidence interval (CI) 0.66-0.97). No statistical significant different mortality risk was observed when comparing patients operated on within or after 24 hours (RR 0.82, 95% CI 0.67-1.01). Adjusted data demonstrated fewer complications (8% vs. 17%) in patients who had early surgery, and increasing risk for pressure ulcers with increased time of delay in another study. Early hip surgery within 48 hours was associated with lower mortality risk and fewer perioperative complications.
A naphthyridine‐derived expanded pincer ligand is described that can host two copper(I) centers. The proton‐responsive ligand can undergo reversible partial and full dearomatization of the ...naphthyridine core, which enables cooperative activation of H2 giving an unusual butterfly‐shaped Cu4H2 complex.
Double trouble! A new dinucleating ligand is described that can bind two copper(I) centers. Reversible dearomatization of the ligand's naphthyridine core enables cooperative activation of H2 giving an unusual butterfly‐shaped Cu4H2 complex.
The Ru-catalyzed direct amination of alcohols with ammonia was investigated for the RuHCl(CO)(PPh3)3/Xantphos system in order to gain mechanistic insight. For several Ru(II) precursor complexes the ...influence of different additives on catalytic performance was investigated. NMR studies revealed that the reaction of RuHCl(CO)(PPh3)3/Xantphos with the alcohol in the presence of a strong base initially formed an inactive dihydrido Ru species. However, by addition of a ketone, the dihydride was (re)activated, where the corresponding imine is the actual activator, formed by immediate condensation of the ketone with ammonia. In the absence of a base, added ketone significantly enhanced catalyst activity. Catalytically inactive RuCl2(PPh3)3 could be activated by base, demonstrating that also complexes without the CO ligand give active catalysts. On the basis of these observations a mechanism was proposed, closely related to known transfer hydrogenation mechanisms.
Summary
Objective
This study aimed to analyze the retention rate of lacosamide (LCM) in patients with epilepsy and intellectual disabilities (IDs), to identify factors influencing retention rate, and ...to investigate the LCM retention rate with and without concomitant sodium channel blocker (SCB). We hypothesized that the retention rate of LCM with concomitant SCB would be lower than without SCB.
Methods
Using the Kaplan‐Meier estimator, we conducted a monocentric, retrospective, observational, open‐label study to evaluate LCM retention rates in patients with IDs and drug‐resistant epilepsy. In addition, the impact of therapy‐related variables on the long‐term retention of LCM was evaluated.
Results
One hundred thirty‐six subjects with IDs and drug‐resistant epilepsy were included (age 2–66 years); most patients had focal epilepsy. Long‐term retention rates were 62.0% at 1 year, 43.7% at 2 years, and 29.1% at 3 and 4 years. Reasons for LCM discontinuation included insufficient therapeutic benefits (69%), adverse events (11%), or a combination of both factors (8%). The LCM retention rate was influenced by the number of background antiepileptic drugs (AEDs). An additional and independent influence of concomitant therapy with SCB on retention rate could not be confirmed.
Significance
One of the major challenges in medically caring for patients with epilepsy and IDs is the high rate of drug resistance. However, there is a lack of evidence‐based information about the efficacy and tolerability of AEDs in this population. It has been shown that concomitant SCB use is a key factor in increasing the risk of LCM failure in children with epilepsy. This finding has not been replicated in our predominantly adult sample of patients with IDs.
With this report, the space group of Zn(Nal)(DACH)2Cl is corrected (Nal: nalidixic acid mono-anion; DACH: diaminocyclohexane) from its wrong description in the literature. In the correct, ...non-centrosymmetric space group P1, the crystal structure is well ordered and the stereochemistry is correct. Crystallographic tools to recognize the correct symmetry are described. This work encourages experienced and inexperienced scientists to remain critical about the output of automatic, black-box crystallographic software.
Monodisperse oligodimethylsiloxanes end-functionalized with the hydrogen-bonding ureidopyrimidinone (UPy) motif undergo phase separation between their aromatic end groups and dimethylsiloxane ...midblocks to form ordered nanostructures with domain spacings of <5 nm. The self-assembly behavior of these well-defined oligomers resembles that of high degree of polymerization (N)–high block interaction parameter (χ) linear diblock copolymers despite their small size. Specifically, the phase morphology varies from lamellar to hexagonal to body-centered cubic with increasing asymmetry in molecular volume fraction. Mixing molecules with different molecular weights to give dispersity >1.13 results in disorder, showing importance of molecular monodispersity for ultrasmall ordered phase separation. In contrast, oligodimethylsiloxanes end-functionalized with an O-benzylated UPy derivative self-assemble into lamellar nanostructures regardless of volume fraction because of the strong preference of the end groups to aggregate in a planar geometry. Thus, these molecules display more classically liquid-crystalline self-assembly behavior where the lamellar bilayer thickness is determined by the siloxane midblock. Here the lamellar nanostructure is tolerant to molecular polydispersity. We show the importance of end groups in high χ–low N block molecules, where block-copolymer-like self-assembly in our UPy-functionalized oligodimethylsiloxanes relies upon the dominance of phase separation effects over directional end group aggregation.
Adaptive ligands, which can adapt their coordination mode to the electronic structure of various catalytic intermediates, offer the potential to develop improved homogeneous catalysts in terms of ...activity and selectivity. 2,2′-Diphosphinobenzophenones have previously been shown to act as adaptive ligands, the central ketone moiety preferentially coordinating reduced metal centers. Herein, the utility of this scaffold in nickel-catalyzed alkyne cyclotrimerization is investigated. The complex ( p‑tolL1)Ni(BPI) ( p‑tolL1 = 2,2′-bis(di(para-tolyl)phosphino)-benzophenone; BPI = benzophenone imine) is an active catalyst in the 2 + 2 + 2 cyclotrimerization of terminal alkynes, selectively affording 1,2,4-substituted benzenes from terminal alkynes. In particular, this catalyst outperforms closely related bi- and tridentate phosphine-based Ni catalysts. This suggests a reaction pathway involving a hemilabile interaction of the CO unit with the nickel center. This is further borne out by a comparative study of the observed resting states and DFT calculations.
•Consequences of symmetry choice in crystal structure determination.•Detection of wrong space group symmetry.•Validation of crystallographic data quality.
We comment on the crystal structure of an ...enanantipure chiral zinc complex which has been described by Ivanova & Spiteller (2022) erroneously in a centrosymmetric space group with the metal on an inversion center. Subsequent information about thermal motion, octahedral distortion and charge density in their article is highly flawed.
Reacting white phosphorus (P4) with sterically encumbered aryl lithium reagents (aryl=2,6‐dimesitylphenyl or 2,4,6‐tBu3C6H2) and B(C6F5)3 gives the unique, isolable Lewis acid stabilized ...bicyclo1.1.0tetraphosphabutane anion. Subsequent alkylation of the nucleophilic site of the RP4 anion gives access to non‐symmetrical disubstituted bicyclic tetraphosphorus compounds. This novel method enables PC bond formation in a controlled fashion using white phosphorus as starting material.
Controlling P4 transformations: Reacting P4 with congested aryl lithium reagents and B(C6F5)3 gives unique, Lewis acid stabilized bicyclo1.1.0tetraphosphabutane anions. Alkylating their nucleophilic site results in a non‐symmetrical disubstituted bicyclic tetraphosphorus compound. This method enables the formation of PC bonds in a controlled fashion using white phosphorus as the starting material.
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