Abstract Background Balance is a complex process involving the coordinated activities of multiple sensory, motor and biomechanical components. Balance function may be disturbed in subjects suffering from hearing loss but the impairment has been attributed to the pathology underlying the hearing loss. Aim The purpose of the study was to investigate the possible interference of simulated conductive hearing loss with the ability to maintain postural balance. Methods Twenty normal hearing...
Wed Nov 06, 2019 19:20
Nickel-titanium (NiTi) rotary files have enabled efficient root canal preparations that maintain the canal center with fewer aberrations compared to hand files. However, NiTi rotary files are susceptible to fracture, which can thereby compromise root canal treatment. Therefore, NiTi files have been developed to enhance fracture resistance by modifying design and thermal treatment. The objective of this study was to compare the torsional fatigue resistance and bending resistance of NiTi files manufactured...
08:05
Parasitic Entamoeba spp. can infect many classes of vertebrates including humans and pigs. Entamoeba suis and zoonotic Entamoeba polecki have been identified in pigs, and swine are implicated as potential reservoirs for Entamoeba histolytica. However, the prevalence of Entamoeba spp. in pigs in southeastern China has not been reported. In this study, 668 fecal samples collected from 6 different regions in Fujian Province, southeastern China, were analyzed to identify three Entamoeba species by nested...
05:05
Background. Delayed rectifier K+-channel, Kv1.3, is most predominantly expressed in T-lymphocytes and macrophages. In such leukocytes, Kv1.3-channels play pivotal roles in the activation and proliferation of cells, promoting cellular immunity. Since leukocyte-derived cytokines stimulate fibroblasts to produce collagen fibers in inflamed kidneys, Kv1.3-channels expressed in leukocytes would contribute to the progression of tubulointerstitial renal fibrosis. Methods. Male Sprague-Dawley rats that underwent...
05:05
Aim. Carvedilol is a nonselective beta-blocker used to reduce portal hypertension. This study investigated the effects and potential mechanisms of carvedilol in angiotensin II- (Ang II-) induced hepatic stellate cell (HSC) proliferation and contraction. Methods. The effect of carvedilol on HSC proliferation was measured by Cell Counting Kit-8 (CCK-8). Cell cycle progression and apoptosis in HSCs were determined by flow cytometry. A collagen gel assay was used to confirm HSC contraction. The extent...
04:05
Purpose. To predict the early recurrence after full endoscopic lumbar discectomy, we analyzed factors related to demographic factor anatomical factors, operative method, and postoperative management, and predicted the possibility of recurrence according to the scoring system. Materials and Methods. In this prospective study, we enrolled 300 patients who underwent 1 out of 3 surgical procedures. The patients were randomized into one of the following groups: group A (), transforaminal inside-out approach;...
02:05
Objective. The aim of the present study was to characterize a novel resin-based monoblock endodontic obturation system consisting of a polymeric cone and a resin-based endodontic sealer. Methods. The preliminary tests performed for the experimental cone were as follows: cohesive strength, dimensional stability, standardization of the diameter and taper, calcium ion release, and radiopacity, for the characterization of the experimental sealer, film thickness and flow tests were performed. Tests were...
02:05
Background. Endoscopy has seen a significant development over recent years in various medical fields with its application expanding from the support of minimal invasive surgery to in situ imaging. In this context, the application of endoscopic techniques to assess the quality of the regenerated bone in situ in the drill hole before implant placement is an appealing approach. Aim. The aim of this study was to use short distance support immersion endoscopy (SD-SIE) to compare the quality of regenerated...
Wed Nov 06, 2019 19:05
To evaluate the origin, genetic diversity, and population structure of domesticated rabbits in Kenya, a 263-base pair region of mtDNA D-loop region of 111 rabbits sampled from Kakamega, Vihiga, and Bungoma counties in the western region, Laikipia and Nyandarua counties in the central region, and Kitui, Machakos, and Makueni in the eastern region of the country were analyzed. The average haplotype (0.40702) and nucleotide (0.01494) diversities observed were low, indicating low genetic diversity of...
Wed Nov 06, 2019 19:05
Purpose. Studies on genetic alterations of the heterogenous small cell lung cancer (SCLC) are rare. We carried out the present study to clarify the genomic alterations and TMB levels of Chinese SCLC patients by whole-exome sequencing. Materials and Methods. Whole-exome sequencing by next-generation sequencing technique was implemented on twenty SCLC samples. Significant somatic mutations and copy number variations were screened, followed by comparison with the data extracted from COSMIC. Besides,...
Wed Nov 06, 2019 19:05
Introduction. Chromosomal microarray analysis (CMA) has currently been considered as the first-tier genetic test for patients with developmental delay/intellectual disability (DD/ID) in many countries. In this study, we performed an extensive assessment of the value of CMA for the diagnosis of children with ID/DD in China. Methods. A total of 633 patients diagnosed with DD/ID in West China Second University Hospital, Sichuan University, were recruited from January 2014 to March 2019. The patients...
Wed Nov 06, 2019 19:05
Glypican-3(GPC3) is a transmembrane protein which has been found to be frequently overexpressed on the surfaces of liver cancer (LC) cells, which contributes to both the growth and metastasis of LC cells. Recently, the expression of GPC3 has been reported to be inversely associated with glucose metabolism activity in LC patients, suggesting that GPC3 may play a role in the regulation of glucose metabolism in LC. However, the role of GPC3 in glucose metabolism reprogramming, as well as in LC cell...
Wed Nov 06, 2019 11:05
Ulcerative colitis is a common inflammatory bowel disease, and the activation of thePI3K/AKT and NF-κB signaling pathways plays a pivotal role in its pathogenesis. Dihydroartemisinin (DHA) is a widely used antimalarial drug and has shown anticancer effect partially through inhibiting the activation of PI3K/AKT and NF-κB. This study aimed to investigate the effect of dihydroartemisinin on ulcerative colitis and its mechanism. Adult male C57 mice were subjected to 3.0% dextran sulfate sodium (DSS)...
Wed Nov 06, 2019 10:05
Background. Extended spectrum beta-lactamases (ESBLs) producing Enterobacteriaceae cause severe infections in humans which leads to complicated diseases. There is increasing evidence that cattle contribute to the development and spread of multidrug resistant pathogens and this raises public health concern. Despite this, data on the concurrence of ESBL producing pathogens in cattle, especially in the North-West province are rare. Therefore, the aim of the present study was to isolate, identify and...
Wed Nov 06, 2019 09:05
Objectives. Assessing the therapeutic efficacy of superparamagnetic iron oxide nanoparticles (SPIO) labeled bone marrow-derived mesenchymal stem cells (BM-MSCs) on experimental liver fibrosis and associated dysplasia. Materials and Methods. MSCs were obtained from 10 male Sprague-Dawley rats while 50 female rats were divided into control (CG), liver fibrosis (CCL4, intraperitoneal injection of CCl4 for 8 weeks), and CCL4 rats treated with SPIO-labeled MSCs (MSCs/CCl4) with and without continuing...
Wed Nov 06, 2019 09:05
Background. Developing countries are suffering from the previously existing infectious diseases and alarmingly growing burden of noncommunicable diseases like diabetes mellitus. There is increased speculation that diabetes mellitus might attribute to high infectious diseases burden, such as tuberculosis. The global importance of diabetes mellitus as a tuberculosis-risk factor is still not a well-established fact. Thus, we conducted this study to determine the prevalence of diabetes mellitus and its...
Wed Nov 06, 2019 09:05
Journal of International Medical Research, Ahead of Print.
07:02
Journal of International Medical Research, Ahead of Print.
Tue Nov 05, 2019 09:43
Abstract Purpose : To evaluate and compare the effects of glass fiber (GF), Zirconium oxide nanoparticles (nano‐ZrO2), and silicon dioxide nanoparticles (nano‐SiO2) addition on the flexural strength and impact strength of repaired denture base material. Materials and Methods : Heat‐polymerized acrylic resin specimens were fabricated. All specimens were sectioned centrally and beveled creating 2.5 mm repair gap except for 10 controls. Specimen grouping (n = 10/group) was done according to...
Wed Nov 06, 2019 19:37
Abstract Purpose of Review To review the current status of 8-aminoquinolines in the prophylaxis of malaria among travelers, in light of the recent approval of tafenoquine. Recent Findings Primaquine continues to provide excellent primary prophylaxis against all Plasmodium species. Tafenoquine provides similarly good prophylaxis, with the benefit...
02:00
Abstract Introduction Onychomycosis is an important medical disorder affecting both patients’ health and quality of life. Objective This study was done to compare the efficacy of CO2 laser in combination with topical tioconazole versus CO2 laser only versus topical tioconazole alone in onychomycosis. Patients and methods A total of 120 patients with onychomycosis were randomly assigned to 3 groups. Group A patients were treated with fractional CO2 laser followed by topical tioconazole...
Wed Nov 06, 2019 16:34
Wed Nov 06, 2019 22:33
We have recently completed the largest GWAS on lung cancer including 29,266 cases and 56,450 controls of European descent. The goal of this study has been to integrate the complete GWAS results with a large‐scale expression quantitative trait loci (eQTL) mapping study in human lung tissues (n=1,038) to identify candidate causal genes for lung cancer. We performed transcriptome‐wide association study (TWAS) for lung cancer overall, by histology (adenocarcinoma, squamous cell carcinoma, small cell...
Wed Nov 06, 2019 18:33
This study aimed to analyze the evolution of molecular portraits of BRCA1‐driven ovarian cancer (OC) during treatment. BRCA1 loss‐of‐heterozygosity status (LOH) and exome profiles were investigated in serial OC samples from 13 patients, which included primary tumours (n = 11) obtained before neoadjuvant therapy (NACT) or at primary debulking surgery (PDS), residual post‐NACT cancer tissues (n = 13) and tumour relapses (16 samples from 13 patients). Loss of the wild‐type BRCA1 allele was detected...
Wed Nov 06, 2019 17:37
The heterogeneities of colorectal cancer (CRC) lead to staging inadequately of patients' prognosis. Here, we performed a prognostic analysis based on the tumor mutational profile and explored the characteristics of the high‐risk tumors. We sequenced 338 colorectal carcinomas as the training dataset, constructed a novel 5‐gene (SMAD4, MUC16, COL6A3, FLG, and LRP1B) prognostic signature, and validated it in an independent dataset from The Cancer Genome Atlas (TCGA). Kaplan‐Meier and Cox regression...
Wed Nov 06, 2019 17:33
Little is known about the influence of pre‐ and post‐diagnosis smoking and smoking cessation on ovarian cancer survival. We investigated this relationship in two prospective cohort studies, the Nurses' Health Study (NHS) and NHSII. Analyses included 1279 women with confirmed invasive, stage I‐III epithelial ovarian cancer. We used Cox proportional hazards regression models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for ovarian cancer‐specific mortality by smoking status, adjusting...
Wed Nov 06, 2019 17:24
Consumption of sugary drinks increases the risk of obesity. Previously we reported a positive association between sugar‐sweetened soft drink consumption and obesity‐related cancer but this association was not fully explained by obesity; in contrast, we found no association for consumption of artificially‐sweetened soft drinks. Our aim was to determine whether the consumption of sugar‐sweetened or artificially‐sweetened soft drinks was associated with cancers other than those currently identified...
Wed Nov 06, 2019 17:19
Although alpha-fetoprotein (AFP) is a widely used tumor marker in hepatocellular carcinoma (HCC), 40% of newly diagnosed patients do not have an elevated AFP level. Research has revealed that mutations in the HNF1A binding site of the AFP gene promoter cause significantly elevated serum AFP levels in patients with hereditary persistence of AFP. This study investigated the relationship between HNF1A genetic variants and serum AFP levels. We examined the association between the HNF1A-rs1169288 (A/C),...
07:05
Background. The hypoxic conditions at high altitudes are great threats to survival, causing pressure for adaptation. More and more high-altitude denizens are not adapted with the condition known as high-altitude polycythemia (HAPC) that featured excessive erythrocytosis. As a high-altitude sickness, the etiology of HAPC is still unclear. Methods. In this study, we reported the whole-genome sequencing-based study of 10 native Tibetans with HAPC and 10 control subjects followed by genotyping of selected...
04:05
Lymph node metastatic involvement persists to be among the most important predictors of recurrence and survival in breast carcinoma (BC). This study is aimed at investigating possible gene expression differences in primary BC between patients with or without lymph node involvement at the time of diagnosis. In a retrospective study, we investigated the potential prognostic role of 9 candidate biomarkers at the mRNA level in a cohort of 305 breast cancer patients, 151 lymph node-negative (LN-) and...
Wed Nov 06, 2019 16:15
Multiple Sclerosis (MS) displays a heterogeneous clinical onset and progression, which are mostly unpredictable, but demyelination of the central nervous system (CNS) leads to substantial deficits of sensory, motor, autonomic, and neurocognitive functions. Considering all genetic studies on MS, including the advanced genome-wide association studies, the risk linked to HLA alleles remains the highest among other susceptibility genetic variants. However, given the genetic variability of HLA alleles...
Wed Nov 06, 2019 15:30
Abstract Purpose The aim of the present study was to assess image quality improvement using a metal artifact reduction (MAR) algorithm in cases of medium or large cerebral aneurysms treated with stent-assisted coil embolization (SAC), and to analyze factors associated with the usefulness of the MAR algorithm. Methods We retrospectively evaluated the cone-beam...
02:00
Abstract Purpose To compare the effectiveness of silent susceptibility-weighted angiography (sSWAN), a new imaging technique with lower acoustic noise, with conventional susceptibility-weighted angiography (cSWAN) in the detection of intracranial hemorrhagic lesions. Methods We measured the acoustic and background noise during sSWAN and cSWAN imaging and...
Wed Nov 06, 2019 02:00
Technology in Cancer Research &Treatment, Volume 18, Issue , January-December 2019. Objective:This study aimed to investigate the effect of circular RNA itchy E3 ubiquitin protein ligase on cell proliferation and apoptosis and to explore its target micro-RNAs in prostate cancer cells.Methods:Circular RNA itchy E3 ubiquitin protein ligase expression in human prostate cancer cells and normal prostate epithelial cells was determined by real time-quantitative polymerase chain reaction assay. Circular...
07:00
Authors: Elodie Portanier, Mathieu Garel, Sébastien Devillard, Jeanne Duhayer, Marie-Thérèse Poirel, Hélène Henri, Corinne Régis, Daniel Maillard, Elizabeth Redman, Christian Itty, Patricia Michel and Gilles Bourgoin.<br />Parasite Vol. 26 , page 64<br />Published online: 07/11/2019<br /> Keywords: Ovis gmelini musimon × Ovis sp. ; Host-parasite co-structure ; Population genetics ; Nematode ; Mouflon ; Haemonchus contortus.<img src="http://feeds.feedburner.com/~r/edp_parasite/~4/K6L-jZafKvU"...
02:00
Photodynamic therapy (PDT) has extraordinary promise for the treatment of many cancers. Yet, its clinical progress is impaired by the intrinsic hypoxic tumor microenvironment that limits PDT efficacy and the safety concern associated with biological specificity of photosensitizers or vehicles. Here, we demonstrate that rationally designed DNA nanosponges can load and delivery photosensitizer effectively, target tumor precisely, and relieve hypoxia‐associated resistance remarkably to enhance the...
Wed Nov 06, 2019 17:09
The ophiobolin sesterterpenes are notable plant pathogens, which have recently elicited significant chemical and biological attention due to their intriguing carbogenic frameworks, reactive functionality, and emerging anticancer profiles. Herein we report a total synthesis of (+)‐6‐epi‐ophiobolin A in 14 steps, a task which addresses construction of the synthetically challenging spirocyclic tetrahydrofuran motif as well as several other key stereochemical problems. This work demonstrates a streamlined...
Wed Nov 06, 2019 22:12
A palladium–borane dance: An anionic reaction pathway involving hydride insertion into a Pd→B bond, C−Cl bond activation by an anionic Pd0 species, and B‐assisted C−H bond formation has been discovered and leveraged into catalysis of hydro‐/deutero‐dechlorination. The boron acts as an acceptor towards Pd via the Pd→B interaction (see figure), but as a donor in the Pd0 borohydride thanks to B‐H‐Pd bridging. Abstract Metal–Lewis acid cooperation provides new opportunities in catalysis. In this...
Wed Nov 06, 2019 22:00
Natural products (NPs) from microorganisms have been important sources for discovering new therapeutic and chemical entities. While their corresponding biosynthetic gene clusters (BGCs), in general, can be easily identified by gene‐sequence‐similarity‐based bioinformatics strategies, the actual access to these NPs for structure elucidation and bioactivity testing remains difficult, time‐consuming and costly. Deletion of the gene encoding the RNA chaperone, Hfq, that often affects virulence in different...
Wed Nov 06, 2019 20:04
A novel and unusual palladium‐catalyzed [4+2] annulation of cyclopropenes with benzosilacyclobutanes is reported. This reaction was completed through chemoselective Si‐C(sp 2 ) bond activation synergized with ring expansion/insertion of cyclopropenes for the formation of new C(sp 2 )‐C(sp 3 ) and Si‐C(sp 3 ) bonds. An array of newly elusive bicyclic skeleton with high strain, sila‐bicyclo[4.1.0]heptanes, was formed with good yields and excellent diastereoselectivity under mild conditions....
Tue Nov 05, 2019 19:11
The synthesis of chiral C1‐symmetrical copper(I) complexes supported by chiral carbene ligands is described. These complexes are yellow emitters with modest quantum yields. Circularly polarized luminescence (CPL) spectra show a polarized emission band with dissymmetry factors | g lum | = 1.2 x 10 −3 . These complexes represent the first reported examples of molecular copper(I) complexes exhibiting circularly polarized luminescence. In contrast with most CPL emitting molecules which possess either...
Tue Nov 05, 2019 19:09
Our lab has developed a new series of self‐immolative MR agents for the rapid detection of enzyme activity in mouse models expressing β‐galactosidase (β‐gal). We investigated two molecular architectures to create agents that detect β‐gal activity by modulating the coordination of water to Gd(III). The first is an intermolecular approach, wherein we designed several structural isomers to maximize coordination of endogenous carbonate ions. The second involves an intramolecular mechanism for q modulation....
Tue Nov 05, 2019 19:08
The first total synthesis of the caged monoterpene indole alkaloid cymoside is reported. This natural product displays a unique hexacyclic‐fused skeleton whose biosynthesis implies an early oxidative cyclisation of strictosidine. Our approach to the furo[3,2‐ b ]indoline framework relied on an unprecedented biomimetic sequence which started by the diastereoselective oxidation of the indole ring into a hydroxyindolenine which triggered the addition of an enol ether and was followed by the trapping...
Tue Nov 05, 2019 18:51
Zeolites often act as host materials to encapsulate guest molecules to enrich their functions and applications, particularly in heterogeneous catalysis. Unfortunately, directly imaging guest molecules residing in the intact microporous structure of a zeolite has long been a challenge. Here, we report that integrated differential phase‐contrast scanning transmission electron microscopy (iDPC‐STEM) is capable of directly probing guest molecules in zeolites, due to its sufficient and interpretable image...
Tue Nov 05, 2019 18:11
Ligand‐protected gold nanoclusters (AuNCs) have emerged as a new class of electrochemiluminescence (ECL) luminophores for their interesting catalytic and emission properties, although their quantum yield ( Φ ECL ) in aqueous medium is low with a poor mechanistic understanding of the ECL process. Herein, we communicate that drying AuNCs on electrodes enabled both enhanced electrochemical excitation by an electrocatalytic effect, and enhanced emission by aggregation‐induced ECL (AIECL) for 6‐aza‐2‐thiothymine...
Tue Nov 05, 2019 17:45
Direct conversion of methane to value‐added chemicals with high selectivity under mild conditions remains a great challenge in catalysis. Herein, we report a new kind of single chromium atoms supported on titanium dioxide nanoparticles as an efficient heterogeneous catalyst for direct methane oxidation to C1 oxygenated products with H2O2 as oxidant under mild condition. The highest yield for C1 oxygenated products can be reached as 57.9 mol/molCr with selectivity of around 93% at 50ºC for 20 h, which...
Tue Nov 05, 2019 17:42
Gas Separation In their Communication on https://doi.org/10.1002/anie.201909490page 16390 ff., K. Eum, M. Tsapatsis et al. describe the separation of oxygen from air by modified ZIF membranes. The permeation properties of the membranes are reversible and can be tailored to suit their application.
Mon Nov 04, 2019 22:49
The stereodivergent Ir‐catalyzed allylic alkylation and fluorination of acyclic ketones is described. α ‐Pyridyl‐ α ‐fluoroketones with vicinal tertiary and quaternary stereocenters were obtained in moderate to excellent yields and stereoselectivities. Distinct from the known stereodivergent synthesis where two different chiral catalysts are required in general, herein we report a sequence‐dependent stereodivergent synthesis. With only one single chiral Ir catalyst, all four possible stereoisomers...
Wed Nov 06, 2019 19:06
Copper‐based ternary (I‐III‐IV) chalcogenide nanocrystals (NCs) are compositionally‐flexible semiconductors that do not contain Lead (Pb) or Cadmium (Cd). Cu‐In‐S NCs are the dominantly studied member of this important materials class and have been reported to contain optically‐active defect states. However, there are minimal reports of In‐free compositions that exhibit efficient PL. Here, we report a novel solution‐phase synthesis of ~4 nm defective nanocrystals (DNCs) composed of Copper, Aluminum,...
Wed Nov 06, 2019 19:05
Poor control on the exfoliation of covalent organic frameworks (COFs) remains a disadvantage for their application as two‐dimensional (2D) nanosheets. An equally important problem that needs attention is the reversible control on the available surface charges on COF. Herein, we report an efficient strategy for the reversible exfoliation, re‐stacking and surface charge control of propidium iodide‐based ionic covalent organic framework (iCOF), PI‐TFP, using cucurbit[7]uril (CB[7]) induced molecular...
Wed Nov 06, 2019 18:40
Small peptides containing combinations of cysteine, tyrosine, histidine and serine residues react with octafluorocyclopentene (OFCP) to afford atypically structured macrocycles via successive vinylic substitutions. The reactions proceed rapidly in air at 0 ˚C and are tolerant of spectating tryptophan, asparagine, glutamine and threonine residues. Hexapeptides of consensus sequence YXCXXC displace four fluorine atoms from OFCP to generate fluorinated macrobicyclic compounds that display dual turn...
Wed Nov 06, 2019 18:36
A nickel‐catalyzed conjunctive cross‐coupling of alkenyl carboxylic acids, aryl iodides, and aryl/alkenyl boronic esters is reported. The reaction delivers the desired 1,2‐diarylated and 1,2‐arylalkenylated products with excellent regiocontrol. To demonstrate the synthetic utility of the method, a representative product is prepared on gram scale and then diversified to eight 1,2,3‐trifunctionalized building blocks using two‐electron and one‐electron logic. Using this method, three routes toward bioactive...
Wed Nov 06, 2019 18:14
We report a common strategy to facilitate the syntheses of the polycyclic alkaloids (−)‐FR901483 ( 1 ) and (+)‐TAN1251C ( 2 ). A divergent synthetic strategy provides access both natural products through a pivotal spirolactam intermediate ( 3 ), which can be accessed on a gram‐scale. A photocatalytic olefin hydroaminoalkylation brings together three readily available building blocks and forges the majority of the carbon framework present in 1 and 2 in a single operation, leading to concise...
Wed Nov 06, 2019 18:00
3 in 1: A convenient and efficient domino aryne process was developed under transition‐metal‐free conditions to afford tetra‐ and pentacyclic ring systems. Chemoselective control at both the 1,2‐aryne and 2,3‐aryne stages enabled three new chemical bonds, namely one C−N and two C−C bonds, and two benzofused rings to be constructed concomitantly. Abstract A convenient and efficient domino aryne process was developed under transition‐metal‐free conditions to generate a range of tetra‐ and pentacyclic...
Wed Nov 06, 2019 16:07
Protective coating: Li amalgam was studied for Li protection. The rational design of a Li anode with such a protective layer affords much improved cycling performance at practically high currents and capacities. Coupled with high‐loading cathodes, the protected hybrid anodes demonstrate significantly improved cell stability, indicating its reliability for practical development of Li metal batteries. Abstract Dendrite formation is a critical challenge for the applications of lithium (Li) metal...
Wed Nov 06, 2019 16:06
One way or the other: Enynes bearing a tethered carbonyl group are transformed into furans upon catalytic hydrogenation using a ruthenium catalyst. Strikingly though, the reaction can follow two distinct pathways, each of which involves discrete metal carbene intermediates. They differ in that the hydrogenation and carbene formation are either synchronized (gem‐hydrogenation) or fully uncoupled. Abstract Enynes with a tethered carbonyl substituent are converted into substituted furan derivatives...
Wed Nov 06, 2019 16:04
Chiral supramolecular polymerization is controlled, resulting from the tuning of mechanical stimulus. Weak, green emissions were converted into strong blue emissions by tuning the mechanical stimulus. The strong blue emissions were caused by an aggregation‐induced emission (AIE) effect during the formation of a supramolecular polymer. Abstract Finely controlled circularly polarized luminescence (CPL) supramolecular polymerization based on a tetraphenylethene core with four l‐ or d‐alanine branch...
Wed Nov 06, 2019 16:04
PO+ and PO2 + cations stabilized by cyclopropenylidene have been prepared by an atomically precise delivery of P+ and O atoms. The former species exhibits ambiphilic reactivity, while both species acts as electrophiles in reactions with fluoride. Abstract The salts [(BAC)2PO][BF4] (5) and [(BAC)2PO2][BF4] (4) (BAC=bis(diisopropylamino) cyclopropenylidene), consisting of the PO+ and PO2+ cations, respectively, coordinated to the singlet carbenes, have been prepared. Computational investigations...
Wed Nov 06, 2019 16:03
Coupling therapy: In organic electronics, J‐type coupling between monomers along the chain and H‐type coupling of chromophores between chains compete, which makes the two types of coupling hard to discern in the ensemble. A single‐molecule H‐type aggregate of fixed spacing and variable length of up to 10 nm is introduced, and HJ‐type aggregate formation is visualized intuitively in the scatter of single‐molecule spectra. Abstract Strong dipole–dipole coupling within and between π‐conjugated...
Wed Nov 06, 2019 16:03
MXene Ti3C2T x nanosheets were functionalized by hydrophilic or hydrophobic groups to tune the size and wettability of 2D nanochannels for elucidating the molecular transport mechanism of lamellar membranes. Hydrophilic nanochannels induce ordered alignment of polar molecules, which contributes to their fast transport, and thus their permeance is much higher than that in hydrophobic nanochannels with disordered molecular configuration. Abstract Lamellar membranes with well‐defined...
Wed Nov 06, 2019 16:03
“My greatest achievement has been the synthesis of artemisinin. My biggest motivation was to make the ambitions of my youth become reality today …” Find out more about Wanbin Zhang in his Author Profile.
Wed Nov 06, 2019 16:02
Solid proof: The formation of a novel pentavalent plutonium solid phase was observed on the pathway from aqueous PuVI to PuO2 nanoparticles by applying a high energy resolution fluorescence detection method at the Pu M4 and L3 edges and electronic structure calculations. Abstract Here we provide evidence that the formation of PuO2 nanoparticles from oxidized PuVI under alkaline conditions proceeds through the formation of an intermediate PuV solid phase, similar to NH4PuO2CO3, which is stable...
Wed Nov 06, 2019 16:01
Coordination mode matters: The first example of carboxy group assisted, remote‐selective meta‐C(sp2)−H activation through a possible κ 2 coordination has been developed, thus suppressing the ortho‐C−H activation thorugh κ 1 coordination. Besides meta‐C−H olefination, direct meta‐arylation of hydrocinnamic acid derivatives with low‐cost aryl iodides has been achieved for the first time. These findings may motivate the exploration of novel selectivities and reactivities for carboxyl assisted C−H...
Wed Nov 06, 2019 16:00
Mitsunobu revisited: The use of (2‐hydroxybenzyl)diphenylphosphine oxide as an efficient catalyst has recently enabled the development of a catalytic redox‐neutral Mitsunobu reaction. This reaction constitutes the first intermolecular stereospecific substitution of non‐allylic alcohols where only water is formed as a by‐product. Abstract The stereospecific substitution of non‐derivatized and non‐allylic enantioenriched alcohols with only water as a by‐product would enable the use of readily...
Wed Nov 06, 2019 15:59
All in a twirl: The gram‐scale synthesis of a series of azaoxa[7]‐, [10]‐, and [13]helicenes is described. The synthesis is based on iterative oxidative furan formation between 3,6‐dihydroxycarbazoles and/or 2‐naphthols. The optically pure [13]helicenes can be synthetically functionalized both at the termini (see picture: blue) and the periphery (red). Abstract Fully aromatic helicenes with more than one pitch‐length are illustrious synthetic targets with potential applications in advanced...
Wed Nov 06, 2019 15:58
A family of compact low‐molecular‐weight cyclic alkenylsulfonyl fluorides can be readily prepared from the corresponding alkenyl triflates using palladium catalysis. These densely functionalized reagents undergo a diverse range of derivatization reactions, including substitution at sulfur, conjugate addition, and N‐functionalization. Abstract A series of low‐molecular‐weight, compact, and multifunctional cyclic alkenylsulfonyl fluorides were efficiently prepared from the corresponding alkenyl...
Wed Nov 06, 2019 15:57
CASH flow: Catalytically active supramolecular hydrogels (CASHs) generated from a porous polymer foam by an enzyme‐assisted self‐assembly strategy are ideal catalytic phases for continuous flow. A hydrogel prepared from an original bis‐phosphorylated heptapeptide enables highly efficient ester hydrolysis and kinetic resolution. Abstract Inspired by biology, one current goal in supramolecular chemistry is to control the emergence of new functionalities arising from the self‐assembly of molecules....
Wed Nov 06, 2019 15:56
Emulsion‐templated self‐assembly produces reproducible and surface‐modification‐free, quasi‐spherical colloidal aggregates which remain stable for days. The high stability and strong plasmonic enhancement of these aggregates allow accurate and quantitative SE(R)RS detection of weakly adsorbing analytes in protein‐rich biomedia to be achieved. Abstract Au/Ag colloids aggregated with simple salts are amongst the most commonly used substrates in surface‐enhanced (resonance) Raman spectroscopy...
Wed Nov 06, 2019 15:55
A highly diastereo‐ and enantio‐selective method for the asymmetric synthesis of molecules containing helicene and stereogenic axes was developed based on organocatalysis. Various compounds bearing both helical and axial stereogenic elements were obtained in excellent enantioselectivities. Abstract A highly diastereo‐ and enantio‐selective method for the asymmetric synthesis of molecules containing helicenes and stereogenic axes was developed based on organocatalysis. Various compounds bearing...
Wed Nov 06, 2019 15:55
Back in black: Surprisingly strong activation effects of black phosphorus (BP) on Pt catalysts and subsequent modulation the surface electronic structure of Pt result in greatly enhanced catalytic activity in the hydrogen evolution reaction (HER). Abstract Modulation of the electronic structure of metal catalysts is an effective approach to optimize the electrocatalytic activity. Herein, we show a surprisingly strong activation effect of black phosphorus (BP) on platinum (Pt) catalysts to give...
Wed Nov 06, 2019 15:55
Wed Nov 06, 2019 15:55
Solid as a rock: The unsatisfactory electrochemical performance in solid‐state batteries originates from internal strain‐induced contact loss, heterogeneous phase transformation, and the augmentation of metallic surface passivation layers. With in situ growth of solid sulfide electrolyte into 3D FeS2 microstructure, these issues can be significantly inhibited and superior electrochemical performance can be achieved. Abstract All‐solid‐state batteries have attracted attention owing to the potential...
Wed Nov 06, 2019 15:54
Six centuries after the discovery of the simplest nitric acid ester, methyl nitrate (H3CONO2), experimental solid‐state and gas‐phase structures as well as energetic properties are compared with those of the new monofluorine‐substituted analogue, fluoromethyl nitrate (FH2CONO2). Abstract An improved synthesis of the simplest nitric acid ester, methyl nitrate, and a new synthesis of fluoromethyl nitrate use the metathesis of the corresponding iodomethanes with silver nitrate. Both compounds...
Wed Nov 06, 2019 15:54
I pod: The synergic effect of the strong binding of RuO2 to I2 and the strong solvation effect of DMSO to I2 is found to invert the direction of the well‐known reaction I−+I2⇌I3− to the left‐hand side. A Li–O2 battery with the Li/DMSO+LiI/RuO2 structure had enhanced stability compared to one with TEGDME. Abstract An exceptionally strong solvation effect of dimethyl sulfoxide (DMSO) on I2 is identified by the largest shift observed so far of the I2 Raman peak with respect to I2 vapor and by...
Wed Nov 06, 2019 15:53
A photo‐promoted Li‐O2 battery has carbon nitride as a bifunctional photocatalyst to accelerate the formation and decomposition of Li2O2 in the discharge and charge process. It realizes photo‐energy conversion and storage in a Li‐O2 battery with a round‐trip efficiency of 95.3 % and an output energy density increase of 23.0 % compared to that in the dark. Abstract A photo‐involved Li‐O2 battery with carbon nitride (C3N4) is presented as a bifunctional photocatalyst to accelerate both oxygen...
Wed Nov 06, 2019 15:53
Genome mining led to the discovery of thuricin Z, a novel sactibiotic from Bacillus thuringiensis that exhibits narrow‐spectrum antibacterial activity against Bacillus cereus. Unusually, the gene cluster involves two radical SAM enzymes (ThzC and D) that are highly divergent but produce the same sactionine ring from the precursor peptide ThzA in vitro. Functional characterization suggests that thuricin Z acts by permeabilizing the bacterial cell membrane. Abstract Sactionine‐containing antibiotics...
Wed Nov 06, 2019 15:49
The four core disaccharides required for heparan sulfate (HS)/heparin oligosaccharide synthesis were efficiently generated from natural polysaccharides. Rapid access to these key building blocks will greatly facilitate the generation of comprehensive libraries of HS oligosaccharides for unlocking the sulfation code and understanding the roles of glycosaminoglycans in physiology and disease. Abstract The complex sulfation motifs of heparan sulfate glycosaminoglycans (HS GAGs) play critical roles...
Wed Nov 06, 2019 15:48
A highly efficient asymmetric cascade reaction of β,γ‐unsaturated α‐ketoesters and diazoimides was realized by using a bimetallic rhodium(II)/chiral N,N′‐dioxide‐zinc(II) catalytic system. The corresponding oxa‐bridged oxazocine products bearing different substituents were obtained in moderate to excellent yields with excellent enantioselectivity under mild reaction conditions. Abstract Oxa‐bridged oxazocines bearing three chiral carbon centers were synthesized efficiently through a bimetallic...
Wed Nov 06, 2019 15:48
Every which way and loose: A single amphiphilic thermoresponsive diblock copolymer can reversibly form spheres, worms or vesicles in aqueous solution. Self‐consistent mean field theory indicates that this rich self‐assembly behavior arises from the temperature‐dependent degree of hydration of the structure‐directing hydrophobic poly(2‐hydroxypropyl methacrylate) block. Abstract It is well‐known that the self‐assembly of AB diblock copolymers in solution can produce various morphologies depending...
Wed Nov 06, 2019 15:47
High‐lying SOMO radicals, generated in situ under visible‐light photoredox conditions, undergo an efficient addition to highly strained bicyclo[1.1.0]butanes, providing a straightforward access to valuable alkylated cyclobutanes. Abstract A new photoredox‐catalyzed decarboxylative radical addition approach to functionalized cyclobutanes is described. The reaction involves an unprecedented formal Giese‐type addition of C(sp3)‐centered radicals to highly strained bicyclo[1.1.0]butanes. The mild...
Wed Nov 06, 2019 15:46
Reaction of carbon monoxide with tBu2MeSiLi yields the first stable tetra‐silyl di‐ketyl biradical 2; with silenyl lithium 1 silaallenolate 3 is obtained.In 3 the bond in the inserted CO molecule is fully cleaved. Both 2 and 3 were characterized by X‐ray crystallography and biradical 2 also by EPR spectroscopy. Density functional theory (DFT) calculations suggest mechanisms for these reactions. Abstract Reactions of carbon monoxide (CO) with tBu2MeSiLi and (E)‐(tBu2MeSi)(tBuMe2Si)C=Si(SiMetBu2)Li⋅2 THF...
Wed Nov 06, 2019 15:46
Functionalization of P ligands: The first metal complexes of diorganopentaphosphorus cations [P5R2]+ (R=Cy, iPr) have been prepared from tetrachlorogallate salts [P5R2]GaCl4 and cyclopentadienyl cobalt and nickel complexes (CpAr=C5(C6H4‐4‐Et)5). The installation of additional chloro, cyano, and cyclohexyl groups on the pentaphosphorus scaffold illustrates a useful strategy to access highly functionalized polyphosphorus ligands. Abstract The chemistry of polyphosphorus cations has rapidly developed...
Wed Nov 06, 2019 15:46
The nucleation mechanism of crystals of small organic molecules was studied for the crystallization of ibuprofen as a model system. Ibuprofen undergoes liquid–liquid phase separation prior to nucleation and forms a dense liquid phase that is identified as a precursor phase in the nucleation of ibuprofen. These results may provide insight for the development of new pharmaceutical formulations. Abstract The nucleation mechanism of crystals of small organic molecules, postulated based on computer...
Wed Nov 06, 2019 15:45
Herein we report a one‐pot protocol for the oxodealkenylative introduction of carbonyl functionalities into terpenes and terpene‐derived compounds. This transformation proceeds via Criegee ozonolysis of an alkene, reductive cleavage of the resulting α‐alkoxy hydroperoxide, trapping of the generated alkyl radical with TEMPO, and subsequent oxidative fragmentation with MMPP. Using readily available starting materials from chiral pool, a variety of carbonyl‐containing products have been accessed rapidly...
Wed Nov 06, 2019 14:52
Prion‐like trans‐cellular spreading of tau in Alzheimer’s Disease (AD) is mediated by tau binding to cell surface heparan sulfate (HS). However, the structural determinants for tau‐HS interaction are not well understood. Microarray and SPR assays of structurally‐defined HS oligosaccharides show that a rare 3‐O‐sulfation(3‐O‐S) of HS significantly enhances tau binding. In Hs3st1‐/‐ (HS 3‐O‐sulfotransferase‐1 knockout) cells, reduced 3‐O‐S levels of HS diminished both cell surface binding and internalization...
Wed Nov 06, 2019 14:43
In this work, we report for the first time the alkaline periodate oxidation on lignocelluloses for the selective isolation of cellulose nanocrystals (CNCs). With the high concentrations as potassium salt at pH 10, periodate ions predominantly exist as dimeric orthoperiodate ions (H2I2O104‐). With reduced oxidizing activity in alkaline solutions, dimeric orthoperiodate ions preferentially oxidized non‐ordered cellulose regions. The alkaline surroundings promoted the degradation of these oxidized cellulose...
Wed Nov 06, 2019 14:04
Abstract: This contribution details an efficient and controlled photopolymerization regulated by far‐red (λ = 680 nm) and NIR (λ = 780 and 850 nm) light in the presence of aluminum phthalocyanine and aluminum naphthalocyanine. Initiating radicals are generated by photosensitization of peroxides affording an effective strategy that provides controlled polymerizations of a variety of monomers with excellent living characteristics. Critically, the long wavelength irradiation provides penetration through...
Wed Nov 06, 2019 13:49
Cage‐type compounds offer molecule‐level confined spaces with different sizes, shapes, and functional groups for various molecule guests to achieve some specific behaviors/functions, such as ultrahigh affinity of host‐guest recognition, multi‐tunable photophysical property, and highly‐stereoselective/photo‐driven catalysis. Herein, we report the synthesis and characterization of three‐dimensional tetraphenylethene‐based octacationic cage with fluorescent property and host‐guest recognition via CH•••π,...
Wed Nov 06, 2019 13:48
Rational design of adsorbent that targets the marine factors is highly possible to enhance the efficiency for uranium extraction from natural seawater. Herein, based on the photoinduced photothermal, photoelectric, and photocatalytic effects of black phosphorus (BP) nanosheets, a BP‐PAO fiber with enhanced uranium extraction capacity and high antibiofouling activity is fabricated by compositing BP nanosheets into polyacrylamidoxime (PAO). The photothermal effect increases the coordination interaction...
Wed Nov 06, 2019 13:44
Gold(III) pi‐complexes have been authenticated recently with alkenes, alkynes and arenes. The key importance of Pd(II) pi‐allyl complexes in organometallic chemistry (Tsuji‐Trost reaction) prompted us to explore gold(III) pi‐allyl complexes, which have remained so far elusive species. The (P,C)Au(III)(allyl) and (methallyl) complexes 3 and 3’ were readily prepared and isolated as thermally and air‐stable solids. Spectroscopic and crystallographic analyses combined with detailed DFT calculations support...
Wed Nov 06, 2019 13:37
The first total synthesis of nominal harziane diterpenoid 1 is disclosed, whose spectral characteristics did not match those of the reported natural product. Stereochemical analysis and subsequent synthesis of the epimeric tertiary alcohol led to reassignment of configuration of the natural product as shown for 2 . At the heart of the synthesis is an enyne cycloisomerization that sets a key quaternary stereocenter within a cyclobutane with high diastereocontrol. The route features strategies...
Wed Nov 06, 2019 13:25
We report the template‐free synthesis and characterization of a new type of porphyrin/quinoidal bithiophene based conjugated macrocycles. X‐ray crystallographic analysis on the dimer ( 2MC ) reveals a cyclophane‐like geometry with large dihedral angles between the porphyrin and the neighboring thiophene rings. Accordingly, NMR measurements and theoretical calculations confirm a localized aromatic character of the porphyrin/thiophene rings and quinoidal character of the bithiophene linkers. Restricted...
Wed Nov 06, 2019 13:21
Durability of supported transition metal particles catalysts usually suffers from the sintering, which makes the increasement of nanoparticles (NPs) size and loss of reactive surface, resulting in catalysts deactivation. Herein, we discovered a surface digging effect of supported Ni NPs on an amorphous N‐doped carbon, during which the surface‐loaded Ni NPs would etch and sink into the underneath carbon support to prevent sintering. This process is driven by the strong coordination interaction between...
Wed Nov 06, 2019 13:16
The principle of the “amplified halogen bonding (XB) in a small space” is here exploited as a catalytic tool for the activation of a XB acceptor substrate in a nanoconfined environment. The inner cavity of the resorcinarene capsule has been equipped with a XB catalyst bearing an ammonium unit acting as a Trojan horse to drive the catalyst inside the capsule. In the presence of the XB catalyst 5, the capsule is able to catalyze a Michael reaction between N‐methylpyrrole and methyl vinyl ketone. In...
Wed Nov 06, 2019 12:16
Palladium‐catalyzed three‐component carboetherification of cyclic alkenes proceeds to give exclusive trans ‐adducts in excellent enantioselectivity via a Wacker‐type pathway. The reaction is also applicable to other oxygen nucleophiles such as water, phenols and carboxylic acids, as well as some electron‐poor arylamines.
Wed Nov 06, 2019 11:39
Photoconvertible fluorescent proteins have powered significant bioimaging and biomedical advances. However, molecular mechanisms for the light‐induced processes remain elusive due to challenges of tracking chromophore structural dynamics during photoconversion. We implemented time‐resolved electronic and stimulated Raman spectroscopies to reveal two hidden species of an engineered ancestral GFP‐like protein LEA, involving semi‐trapped protonated (GA’) and trapped deprotonated (GB’) chromophores en...
Wed Nov 06, 2019 11:06
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