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Objectives: Anti‐signal recognition particle (SRP) antibodies, markers of immune‐mediated necrotising myopathy, are reportedly related to cardiac involvement; however, whether they are pathogenic to the myocardium remains unclear. We aimed, therefore, to explore the pathogenicity of anti‐SRP antibodies against the myocardium through in vivo and in vitro studies. Methods: Total immunoglobulin G (IgG), purified from patients with positive anti‐SRP antibodies, was passively transferred into C57BL/6 mice. Cardiac function was evaluated via echocardiography and the ventricular pressure–volume loop; cardiac histological changes were analysed using haematoxylin–eosin staining, picrosirius red staining, immunofluorescence and immunohistochemistry. Additionally, reactive oxygen species (ROS) formation was evaluated by dihydroethidium (DHE) staining; mitochondrial morphology and function were evaluated using transmission electron microscopy and seahorse mitochondrial respiration assay, respectively. The myositis cohort at our centre was subsequently reviewed in terms of cardiac assessments. Results: After the passive transfer of total IgG from patients with positive anti‐SRP antibodies, C57BL/6 mice developed significant left ventricular diastolic dysfunction (LVDD). Transcriptomic analysis and corresponding experiments revealed increased oxidative stress and mitochondrial damage in the hearts of the experimental mice. Cardiomyocytes exposed to anti‐SRP‐specific IgG, however, recovered normal mitochondrial metabolism after treatment with N‐acetylcysteine, an ROS scavenger. Moreover, patients positive for anti‐SRP antibodies manifested worse diastolic but equivalent systolic function compared to their counterparts after propensity score matching. Conclusion: Anti‐SRP antibodies may play a pathogenic role in the development of LVDD by promoting ROS production and subsequent myocardial mitochondrial impairment. The inhibition of oxidative stress was effective in reversing anti‐SRP antibody‐induced LVDD. [ABSTRACT FROM AUTHOR]

Asparagus, a vital economic contributor, is a well‐liked vegetable grown around the globe, and some secondary metabolites in its spear are beneficial to human health. Asparagus spears possess a significant quantity of nutrients and phytochemicals; however, the difference in these chemical compositions among various varieties has not been sufficiently studied. This work aimed to detect the chemical compositions of 30 varieties of asparagus and to assess them by principal component analysis (PCA). The results showed that the contents of these chemical compositions varied in varieties. Selenium (Se, 1.12–2.9 μg/100 g dry‐weight [DW]) was abundant in asparagus, with an average dry matter content of 8.25%. Free amino acids (5.60–9.98 g/100 g DW) and polyphenols (6.34–8.67 mg/g DW) were both present in high amounts, along with flavonoids (4.218–8.22 mg/g DW) and protodioscin (0.44–1.96 mg/g DW). Correlation analysis, PCA, and hierarchical cluster analysis were used to conduct a comprehensive evaluation of asparagus. Atlas, Appolo, Jinggang 111, Jingke 2, and WS‐1 were the top five varieties with comprehensive scores. This study provided valuable data for the breeding, quality improvement, processing, and utilization of asparagus varieties in the future. [ABSTRACT FROM AUTHOR]

Architected materials comprising periodic arrangements of cells have attracted considerable interest in various fields because of their unconventional properties and versatile functionality. Although some better properties may be exhibited when this homogeneous layout is broken, most such studies rely on a fixed material geometry, which limits the design space for material properties. Here, combining heterogeneous and homogeneous assembly of cells to generate tunable geometries, a hierarchically architected material (HAM) capable of significantly enhancing mechanical properties is proposed. Guided by the theoretical model and 745 752 simulation cases, generic design criteria are introduced, including dual screening for unique mechanical properties and careful assembly of specific spatial layouts, to identify the geometry of materials with extreme properties. Such criteria facilitate the potential for unprecedented properties such as Young's modulus at the theoretical limit and tunable positive and negative Poisson's ratios in an ultra‐large range. Therefore, this study opens a new paradigm for materials with extreme mechanical properties. [ABSTRACT FROM AUTHOR]

Objective: Previous studies have underlined the genetic susceptibility in the pathogenesis of palindromic rheumatism (PR), but the known PR loci only partially explain the disease's genetic background. We aimed to genetically identify PR by whole‐exome sequencing (WES). Methods: This multicenter prospective study was conducted in 10 Chinese specialized rheumatology centers between September 2015 and January 2020. WES was performed in 185 patients with PR and in 272 healthy controls. PR patients were divided into PR subgroups who were negative for anti–citrullinated protein antibody (ACPA−) and positive for ACPA (ACPA+) according to ACPA titer (cutoff value 20 IU/liter). We conducted whole‐exome association analysis for the WES data. We used HLA imputation to type HLA genes. In addition, we used the polygenic risk score to measure the genetic correlations between PR and rheumatoid arthritis (RA) and the genetic correlations between ACPA− PR and ACPA+ PR. Results: Among 185 patients with PR enrolled in our study, 50 patients (27.02%) were ACPA+ and 135 PR patients (72.98%) were ACPA−. We identified 8 novel loci (in the ACPA− PR group: ZNF503, RPS6KL1, HOMER3, HLA–DRA; in the ACPA+ PR group: RPS6KL1, TNPO2, WASH2P, FANK1) and 3 HLA alleles (in the ACPA− PR group: HLA–DRB1*0803 and HLA–DQB1; in the ACPA+ PR group: HLA–DPA1*0401) that were associated with PR and that surpassed genome‐wide significance (P < 5 × 10−8). Furthermore, polygenic risk score analysis showed that PR and RA were not similar (R2 < 0.025), whereas ACPA+ PR and ACPA− PR showed a moderate genetic correlation (0.38 < R2 < 0.8). Conclusion: This study demonstrated the distinct genetic background between ACPA− and ACPA+ PR patients. Additionally, our findings strengthened that PR and RA were not genetically similar. [ABSTRACT FROM AUTHOR]

Severe coloboma of ocular malignant neoplasms post‐resection poses a reconstructive challenge to surgeons. To compare the practicability, manipulability and outcomes of temporal (myocutaneous) flaps (TFs), forehead (supratrochlear artery/supraorbital artery) flaps (FFs) and buccal (facial artery) flaps (BFs) for periorbital defects reconstruction, a retrospective case series was conducted and evaluated between March 2014 and March 2021. Patient demographics and clinical parameters including age, gender, pathological diagnosis, operative methods, flap selection, operation time, aesthetic satisfaction and follow‐up period were collected. The differences in complications were compared and assessed of the three flaps, including flap survival, venous congestion and donor site healing. Totally, 68 patients who underwent periorbital reconstructive operations because of common ocular malignant tumours were reviewed in this study. As for aesthetic satisfaction, a score more than "moderately dissatisfied" was obtained in 21 patients with TFs (95.5%), and of which the scores in FFs group were 12 cases (60%) and 16 cases with BFs reconstruction (61.5%) (P <.05). Severe microvascular complications underwent re‐exploration operation occurred in one patient with FFs (1.5%) (P >.05). Notable flap necrosis was observed in two patients with BFs repair (2.9%) and in one case with FFs repair (1.5%), with no statistical difference between the three flap selections (P >.05). Moderate venous congestion occurred in one patient with TFs (1.5%), which was fully meliorated non‐surgically. The three familiar facial island flaps are considered as minor trauma and time‐saving process for reconstructing the extensive periorbital defects with comparable ranks of complications. [ABSTRACT FROM AUTHOR]

A thorough assessment of thermal properties in heterogeneous subsurface is necessary in design of low‐temperature borehole heat exchangers (BHEs). A distributed thermal response test (DTRT), which combines distributed temperature sensing (DTS) with a conventional thermal response test (TRT), was conducted in a U‐bend geothermal loop installed in an open borehole at the University of Illinois at Urbana‐Champaign to estimate thermal properties by analyzing the thermal response of different geologic materials while applying a constant heat input rate. Fiber‐optic cables in the DTRT were deployed both inside the U‐bend geothermal loop and in the center of the borehole to improve the accuracy of calculated heat‐loss rates and borehole temperature profile measurements. To assess the subsurface thermal conductivity during the heating phase of the DTRT, a single‐source model and a multi‐source model, both based on the infinite line source method, were developed using the borehole temperature data and temperatures inside and along the outside of the loop, separately. The two models returned similar thermal conductivity values. The multi‐source modeling has the advantage of predicting the thermal conductivity of heterogeneous geologic materials from borehole temperature profiles during the DTRT heating phase. In addition, based on the distributed thermal conductivity measured in the borehole, estimates were made for both radial thermal impacts and the rate of heat loss in the BHE. [ABSTRACT FROM AUTHOR]

The catalytic generation of C(1)‐ammonium enolates from the corresponding α‐silyl‐α‐alkyl substituted carboxylic acids using the isothiourea HyperBTM is reported. This desilylative approach grants access to α‐unsubstituted and α‐alkyl substituted C(1)‐ammonium enolates, which are typically difficult to access through traditional methods reliant upon deprotonation. The scope and limitations of this process is established in enantioselective [2+2]‐cycloaddition processes with perfluoroalkylketones (31 examples, up to 96 % yield and >99 : 1 er), as well as selective [2+2]‐cycloaddition with trifluoromethyl enones (4 examples, up to 75 % yield and >99 : 1 er). Preliminary mechanistic studies indicate this process proceeds through an initial kinetic resolution of an in situ prepared (±)‐α‐silyl‐α‐alkyl substituted anhydride, while the reaction process exhibits overall pseudo zero‐order kinetics. [ABSTRACT FROM AUTHOR]

During pregnancy, humoural immunity is essential for protection against many extracellular pathogens; however, autoimmune diseases may be induced or aggravated. T follicular helper (Tfh) cells contribute to humoural immunity. The aim of this study was to test whether Tfh cell function can be manipulated via hormones. Seventy‐four women who underwent in vitro fertilization were recruited and divided into four groups: menstrual period (MP), controlled ovarian hyperstimulation (COH), embryo transfer (ET) and pregnant after embryo transfer (P). A flow cytometry analysis was performed to identify Tfh cells in peripheral blood mononuclear cells (PBMCs). Bioinformatics analysis revealed a possible pathway between Tfh and B cells. Enzyme‐linked immunosorbent assays were used to detect interleukin (IL)‐21 and IL‐6. The quantitative polymerase chain reaction was performed to quantify BCL‐6, BACH2, XBP‐1, IRF‐4 and G protein‐coupled (GP)ER‐1 mRNA expression. Compared with the MP group, the COH, ET and P groups showed more Tfh and B cells, as well as higher IL‐21, IL‐6, BCL‐6 and BACH2 expression. Furthermore, Tfh cell frequency in PBMCs, as well as serum IL‐21 and IL‐6 levels, were all positively correlated with serum estradiol (E2) levels; the B cell percentage also correlated positively with Tfh cells in PBMCs. Combined with the bioinformatics analysis, XBP‐1, IRF‐4 and GPER‐1 expression was related to E2 levels, both in vivo and in vitro. We speculate that E2 augments Tfh cells and favours humoural immunity. This study indicates that Tfh cell regulation may be a novel target in maintaining the maternal‐foetal immune balance. [ABSTRACT FROM AUTHOR]

Objective: Adult‐onset Still's disease (AOSD) is a severe autoinflammatory disease. Neutrophil activation with enhanced neutrophil extracellular trap (NET) formation is involved in the pathogenesis of AOSD. Functional leukocyte immunoglobulin‐like receptor A3 (LIR‐A3; gene name LILRA3) has been reported to be associated with many autoimmune diseases. We aimed to investigate the association of LILRA3 with disease susceptibility and neutrophil activation in AOSD. Methods: The LILRA3 deletion polymorphism and its tagging single‐nucleotide polymorphism rs103294 were genotyped in 164 patients with AOSD and 305 healthy controls. The impact of LILRA3 on clinical features and messenger RNA expression was evaluated. Plasma levels of LIR‐A3 were detected using enzyme‐linked immunosorbent assay (ELISA), and the correlation between LIR‐A3 plasma levels and disease activity and levels of circulating NET‐DNA was investigated. LIR‐A3–induced NETs were determined using PicoGreen double‐stranded DNA dye and immunofluorescence analysis in human neutrophils and a neutrophil‐like differentiated NB4 cell line transfected with LIR‐B2 small interfering RNA. Results: The findings from genotyping demonstrated that functional LILRA3 was a risk factor for AOSD (11% in AOSD patients versus 5.6% in healthy controls; odds ratio 2.089 [95% confidence interval 1.030–4.291], P = 0.034), and associated with leukocytosis (P = 0.039) and increased levels of circulating neutrophils (P = 0.027). Functional LILRA3 messenger RNA expression was higher in the peripheral blood mononuclear cells (P < 0.0001) and neutrophils (P < 0.001) of LILRA3+/+ patients. Plasma levels of LIR‐A3 were elevated in patients with AOSD (P < 0.0001) and correlated with disease activity indicators and levels of circulating NET–DNA complexes. Finally, enhanced NET formation was identified in neutrophils from healthy controls and patients with inactive AOSD after stimulation of the neutrophils with LIR‐A3. Moreover, NET formation was impaired in NB4 cells after knockdown of LILRB2 gene expression. Conclusion: Our study provides the first evidence that functional LILRA3 is a novel genetic risk factor for the development of AOSD and that functional LIR‐A3 may play a pathogenic role by inducing formation of NETs. [ABSTRACT FROM AUTHOR]

Quaternary phosphonium salts have been extensively used in organic synthesis as Lewis acid organocatalysts. This review covers recent applications of phosphonium salts as Lewis acidic catalysts for Mannich, Strecker, and Friedel‐Crafts reactions for the formation of C−C bonds, annulation reactions, etc., allowing the construction of structurally diverse and synthetically useful architectures. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa PAO1, an opportunistic human pathogen, deploys several strategies to resist antibiotics. It uses multidrug efflux pumps, including the MexAB‐OprM pump, for antibiotic resistance, and it also produces hydrogen sulfide (H2S) that provides some defense against antibiotics. MexR functions as a transcriptional repressor of the mexAB‐oprM operon. MexR responds to oxidative stresses caused by antibiotic exposure, and it also displays a growth phase‐dependent derepression of the mexAB‐oprM operon. However, the intrinsic inducer has not been identified. Here, we report that P. aeruginosa PAO1 produced sulfane sulfur, including glutathione persulfide and inorganic polysulfide, produced from either H2S oxidation or from L‐cysteine metabolism. Sulfane sulfur directly reacted with MexR, forming di‐ and trisulfide cross‐links between two Cys residues, to derepress the mexAB‐oprM operon. Levels of cellular sulfane sulfur and mexAB‐oprM expression varied during growth, and both reached the maximum during the stationary phase of growth. Thus, self‐produced H2S and sulfane sulfur may facilitate antibiotic resistance via inducing the expression of antibiotic resistance genes. [ABSTRACT FROM AUTHOR]

A palladium‐catalyzed asymmetric [4+2] cycloaddition of 2‐methylidenetrimethylene carbonate with alkenes derived from pyrazolones, indandione, or barbiturate has been successfully developed, affording pharmacologically interesting chiral tetrahydropyran‐fused spirocyclic scaffolds. The target compounds were generated in good to excellent yields and with high enantioselectivity (up to 99 % ee). Furthermore, this cycloaddition reaction could be efficiently scaled up, and several synthetic transformations were accomplished for the construction of other useful chiral spiropyrazolone and spiroindandione derivatives. [ABSTRACT FROM AUTHOR]

In order to effectively detect potential geology anomalous bodies in coal bearing formation, such as coal seam thickness variation, small faults, goafs and collapse columns, and provide scientific guidance for safe and efficient mining, the SUMMIT‐II EX explosion‐proof seismic slot wave instrument, produced by German DMT Company, was used to detect the underground channel wave with the help of transmission method, reflection method and transflective method. Region area detection experiment in mining face had been carried out thanks to the advantage of channel wave, such as its great dispersion, abundant geology information, strong anti‐interference ability and long‐distance detecting. The experimental results showed that: (1) Coal seam thickness variation in extremely unstable coal seam has been quantitatively interpreted with an accuracy of more than 80% generally; (2) The faults, goafs and collapse columns could be detected and predicted accurately; (3) Experimental detection of gas enrichment areas, stress concentration regions and water inrush risk zone has been collated; (4) A research system of disaster‐causing geology anomalous body detection by in‐seam seismic survey has been built, valuable and innovative achievements have been got. Series of innovation obtained for the first time in this study indicated that it was more effective to detect disaster‐causing potential geology anomalies by in‐seam seismic survey than by ground seismic survey. It had significant scientific value and application prospect under complex coal seam conditions. [ABSTRACT FROM AUTHOR]

Summary: Ethylenediaminetetraacetate (EDTA) is the most abundant organic pollutant in surface water because of its extensive usage and the recalcitrance of stable metal‐EDTA complexes. A few bacteria including Chelativorans sp. BNC1 can degrade EDTA with a monooxygenase to ethylenediaminediacetate (EDDA) and then use iminodiacetate oxidase (IdaA) to further degrade EDDA into ethylenediamine in a two‐step oxidation. To alleviate EDTA pollution into the environment, deciphering the mechanisms of the metabolizing enzymes is an imperative prerequisite for informed EDTA bioremediation. Although IdaA cannot oxidize glycine, the crystal structure of IdaA shows its tertiary and quaternary structures similar to those of glycine oxidases. All confirmed substrates, EDDA, ethylenediaminemonoacetate, iminodiacetate and sarcosine are secondary amines with at least one N‐acetyl group. Each substrate was bound at the re‐side face of the isoalloxazine ring in a solvent‐connected cavity. The carboxyl group of the substrate was bound by Arg265 and Arg307. The catalytic residue, Tyr250, is under the hydrogen bond network to facilitate its deprotonation acting as a general base, removing an acetate group of secondary amines as glyoxylate. Thus, IdaA is a secondary amine oxidase, and our findings improve understanding of molecular mechanism involved in the bioremediation of EDTA and the metabolism of secondary amines. [ABSTRACT FROM AUTHOR]

In this paper, phosphine-catalyzed [3 + 3] annulation of Morita-Baylis-Hillman carbonates with C, N-cyclic azomethine imines has been achieved. The reaction worked smoothly under mild conditions to afford 4,6,7,11b-tetrahydro-1 H-pyridazino[6,1- a]isoquinoline derivatives in high yields with good to excellent diastereoselectivities. [ABSTRACT FROM AUTHOR]

Some heterotrophic bacteria are able to oxidize sulfide (H2S, HS− and S2−) to sulfite and thiosulfate via polysulfide. The genes coding for the oxidation enzymes in Cupriavidus pinatubonensis JMP134 have recently been identified; however, their regulation is unknown. A regulator gene is adjacent to the operon of the sulfide-oxidizing genes, encoding a σ54-dependent transcription factor (FisR) with three domains: an R domain, an AAA+ domain and a DNA-binding domain. Here it is reported that the regulator responds to the presence of sulfide and activates the sulfide-oxidizing genes. FisR binds to its cognate operator at −114 to −135 bp of the transcription start of the operon. When polysulfide reacts with the R domain of FisR through the three conserved cysteine residues (C53, C64 and C71), FisR activates the expression of the operon. FisR is highly sensitive to polysulfide, activating σ54-dependent transcription of sulfide-oxidizing genes for sulfide removal. Further, sequence analysis indicates that FisR-type regulators are relatively common for controlling sulfide-oxidizing genes under sulfide stress in the Proteobacteria. [ABSTRACT FROM AUTHOR]

Enantioselective synthesis of chiral quinazoline-based heterocycles is achieved through a chiral phosphine-catalyzed [3+3] annulation reaction of quinazoline-based 1,3-dipoles with Morita−Baylis−Hillman carbonates. The reaction proceeds smoothly under mild conditions to give various chiral heterocyclic compounds in high yields with excellent diastereoselectivities and enantioselectivities. Further diverse elaborations of the annulation products work well to produce novel tetrahydroquinazoline derivatives. [ABSTRACT FROM AUTHOR]

Many heterotrophic bacteria contain sulfide:quinone oxidoreductase (SQR) and persulfide dioxygenase (PDO) genes. It is unclear how these enzymes cooperate to oxidise sulfide in bacteria. Cupriavidus pinatubonensis JMP134 contains a gene cluster of sqr and pdo, and their functions were analysed in Escherichia coli. Recombinant E. coli cells with SQR and PDO rapidly oxidised sulfide to thiosulfate and sulfite. The SQR also contains a DUF442 domain that was shown to have rhodanese activities. E. coli cells with PDO and SQR-C94S, an active site mutant of the rhodanese domain, oxidised sulfide to thiosulfate with transitory accumulation of polysulfides. Cellular and enzymatic evidence showed that DUF442 speeds up the reaction of polysulfides with glutathione to produce glutathione persulfide (GSSH). Thus, SQR oxidises sulfide to polysulfides; rhodanese enhances the reaction of polysulfides with glutathione to produce GSSH; PDO oxidises GSSH to sulfite; sulfite spontaneously reacts with polysulfides to generate thiosulfate. The pathway is different from the proposed mitochondrial pathway because it has polysulfides, that is, disulfide and trisulfide, as intermediates. The data demonstrated that heterotrophic bacteria with SQR and PDO can rapidly oxidise sulfide to thiosulfate and sulfite, providing the foundation for using heterotrophic bacteria with SQR and PDO for sulfide bioremediation. [ABSTRACT FROM AUTHOR]

With the use of a bifunctional chiral phosphine as the catalyst, the asymmetric [3+2] annulation of Morita-Baylis-Hillman carbonates with cyclic 1-azadienes proceeded smoothly under mild conditions to give various enantiomerically enriched cyclopentene derivatives bearing three consecutive tertiary stereocenters and a sulfamate moiety in moderate to excellent yields with moderate to excellent enantioselectivities and excellent diastereoselectivities. [ABSTRACT FROM AUTHOR]

A multifunctional chiral phosphine-catalyzed enantioselective [3+2] annulation of Morita-Baylis-Hillman carbonates with barbiturate-derived alkenes has been achieved under mild conditions, providing a variety of chiral spirobarbiturate-cyclopentenes in moderate to excellent yields with moderate to excellent diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

The authors of this study investigate online game consumption in Korea and China, the two key Asian markets, to analyze relationships among country of origin (COO), brand image, belief toward online games, and perceived game quality. Perceived game quality includes three dimensions of quality: product quality, service quality, and gratification quality. The authors survey 355 Korean and Chinese online game users and find that brand image influences quality perceptions directly or indirectly through brand belief. Compared with brand image, COO seems to have indirect and weaker effects on perceptions of game quality. The multigroup research model reveals several crosscountry differences. COO significantly affects beliefs in China but not in Korea. Brand image more highly impacts brand beliefs in Korea than it does in China. To signal superior product or service quality to Chinese users, game developers should highlight COO along with other product information. To appeal to Korean users, game developers should strengthen symbolic aspects of brand image because Koreans react more positively to brand personality, brand content, and corporate identity. [ABSTRACT FROM AUTHOR]

An efficient method for the phosphine-catalyzed [3+2] cycloaddition reaction of azomethine imines with diphenylsulfonyl alkenes to give dinitrogen-fused bi- or tricyclic heterocyclic compounds in high yields has been described. Moreover, two phenylsulfonyl groups installed on the heterocyclic products could be conveniently removed or transformed to other functional groups, making the reaction more useful. [ABSTRACT FROM AUTHOR]

Heterocyclensammlung: Die asymmetrische [3+3] ‐ Cycloaddition von Azomethinyliden, die sich von den Iminen 1 ableiten, mit Azomethiniminen 2 in Gegenwart eines chiralen Ferrocenylphosphan ‐ Kupferkatalysators liefert hoch funktionalisierte heterocyclische Produkte 3 in hoher Ausbeute mit exzellenter Enantio ‐ und Diastereoselektivität (siehe Schema; DBU=1,8 ‐ Diazabicyclo[5.4.0]undec ‐ 7 ‐ en). Die 1,3 ‐ dipolaren Reaktionspartner können leicht aus Aldehyden hergestellt werden. [ABSTRACT FROM AUTHOR]

The concentration of glutathione (GSH), the most abundant intracellular nonprotein thiol and important antioxidant, declines with age and in some age-related diseases. The underlying mechanism, however, is not clear. The previous studies from our laboratory showed that the age-dependent decline in GSH content in Fisher 344 rats was associated with a downregulation of glutamate cysteine ligase (GCL), the rate-limiting enzyme in de novo GSH synthesis. Our recent studies further indicated that the activity and mRNA content of glutathione synthase (GS), which catalyzes the second reaction in de novo GSH synthesis, were also decreased with age in some tissues. No age-associated change was observed in glutathione reductase or γ-glutamyl transpeptidase activities. Also, although GSH content declined with age in both male and female mice, male mice experienced more dramatic age-associated decline in many tissues/organs than female mice. Furthermore, we found that GSH content was significantly decreased in the red blood cells from male Alzheimer disease patients, which was associated with decreases in GCL and GS activities. Finally, we showed that estrogen increased GSH content, GS and GR activities, and GCL gene expression in the liver of both male and female mice. Taken together, our results suggest that (1) GCL plays a critical role in maintaining GSH homeostasis under both physiological and pathological conditions; (2) decreased GSH content may be involved in AD pathology in humans; and (3) estrogen increases GSH content in mice by multiple mechanisms. [ABSTRACT FROM AUTHOR]

Diethyl and dimethyl cyclopropane-1,1-dicarboxylate react in a scalable manner with phthalazinium dicyanomethanides endowed with various functional groups to form 3,4-dihydro-1H-pyrido[2,1-a]phthalazine derivatives in high yields and with excellent diastereoselectivities. Attempts upon enantioselective version of the reaction based on the use of chiral ligands provides the products with low enantiomeric excess only. Further transformations of the products via reduction of one cyano group are described. [ABSTRACT FROM AUTHOR]

The asymmetric [3 + 3] cycloaddition of C,N-cyclic azomethine imines with aryl-substituted Morita-Hillman carbonates (II, IV) is developed using a spirocyclic chiral phosphine as the catalyst. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Cu(I)-Catalyzed Highly Enantioselective [3 + 3] Cycloaddition Between Two Different 1,3-Dipoles, Phthalazinium Dicyanomethanides and Iminoester-Derived Azomethine Ylides" by C. Yuan and others, in the journal "Organic Letters" in 2015.

For the first time allenoate is applied as dipolarophile in thermal 1,3-dipolar cycloaddition of azomethine imines. [ABSTRACT FROM AUTHOR]

Phosphine-catalyzed [3+2] and [4+3]annulation reactions of C,N-cyclic azomethine imines with allenoates have been developed to give a variety of pharmaceutically attractive tetrahydroisoquinoline derivatives in moderate to excellent yields. The two distinct reaction pathways, [3+2] and [4+3]cyclization, depend on the nature of the nucleophilic phosphine and the allenoate. Generally, for α-alkylallenoates, the reactions always proceed with [3 +2]cyclization as the major pathway no matter what phosphine was used; for α-ArCH 2 -substituted allenoates, the reaction pathway was controlled by the phosphine catalyst used.