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Homogeneous and heterogeneous catalyzed reactions can seldom operate synergistically under the same conditions. Here we communicate the use of a single rhodium precursor that acts in both the homogeneous and heterogeneous phases for the asymmetric full saturation of vinylarenes that, to date, constitute an unmet bottleneck in the field. A simple asymmetric hydrogenation of a styrenic olefin, enabled by a ligand accelerated effect, accounted for the facial selectivity in the consecutive arene hydrogenation. Tuning the ratio between the phosphine ligand and the rhodium precursor controlled the formation of homogeneous and heterogeneous catalytic species that operate without interference from each other. The system is flexible in terms of both the chiral ligand and the nature of the external olefin. We anticipate that our findings will promote the development of asymmetric arene hydrogenations.

Aims/Introduction To explore the relationship between handgrip strength per weight (HGS/W), triglyceride glucose index (TyG) and diabetes, and whether lower HGS levels precede TyG in the Chinese elderly population. Materials and Methods Two linear regression models were used to explore the association of whether baseline HGS/W predicted follow‐up variation of TyG or baseline TyG predicted follow‐up variation of HGS/W. The logistic regression model was used to examine the relationship between baseline HGS/W and future diabetes. Results A total of 4,561 participants in the China Health and Retirement Longitudinal Study were enrolled, of which 47.0% were men, and the mean age was 58.7 years (standard deviation 8.68 years). A lower baseline HGS/W significantly correlated with a higher level of follow‐up TyG (β = −0.173, P = 0.002). The baseline level of HGS/W was significantly negatively associated with the incidence risk of diabetes (rate ratio 0.375, P = 0.004). However, in sex stratification, the statistical association between HGS/W and TyG and diabetes was only in men. Conclusions Our results showed that HGS/W was inversely associated with TyG and diabetes, and lower HGS/W levels preceded TyG levels in the elderly population. However, the effect was inconsistent between men and women, and the possible mechanism would require further clarification., Lower handgrip strength levels associated with insulin resistance and diabetes in men, but not in women, probably precede insulin resistance.

Developing green-safe, efficient and recyclable catalysts is crucial for the chemical industry. So far, organic photocatalysis has been proved to be an environmentally friendly and energy-efficient synthetic technology compared with traditional metal catalysis. As a versatile catalytic platform, hyper-crosslinked polymers (HCPs) with large surface area and high stability are easily prepared. In this report, we successfully constructed two porous HCP photocatalysts (TZ-HCPs) featuring s-tetrazine units and surface areas larger than 700 m2 g−1 through Friedel–Crafts alkylation reactions. The rational energy-band structures and coexisting micro- and mesopores endow TZ-HCPs with excellent activities to realize the green synthesis of benzimidazoles (28 examples, up to 99% yield, 0.5–4.0 h) in ethanol. Furthermore, at least 21 iterative catalytic runs mediated by TZ-HCP1D were performed efficiently, with 96–99% yield. This study of TZ-HCPs sheds light on the wide-ranging prospects of application of HCPs as metal-free and green photocatalysts for the preparation of fine chemicals.

In this paper, a dual-ligand design strategy is demonstrated to modulate the performance of the electronically conductive metalorganic frameworks (EC-MOFs) thin film with a spray layer-by-layer assembly method. The thin film not only can be precisely prepared in nanometer scale (20–70 nm), but also shows the pin-hole-free smooth surface. The high quality nano-film of 2,3,6,7,10,11-hexaiminotriphenylene (HITP) doped Cu-HHTP enables the precise modulation of the chemiresistive sensitivity and selectivity. Selectivity improvement over 220% were realized for benzene vs. NH3, as well as enhanced response and recovery properties. In addition, the selectivity of the EC-MOF thin film sensors toward other gases (e.g. triethylamine, methane, ethylbenzene, hydrogen, butanone, and acetone) vs. NH3 at room temperature is also discussed.

Adsorption-based xylene isomer separation is more energy efficient than conventional processes. Herein, three isostructural Hofmann-type porous coordination polymers (PCPs), {M(Pz)[Ni(CN)4]n} (M = Fe, FePzNi, Co, CoPzNi, and Ni, NiPzNi; Pz = pyrazine) were synthesized and shown to exhibit coordination-dependent lability for the selectivity toward p-xylene over m- and o-xylene.

The present study introduces the mechanisms for the oriented external electric field (OEEF)-participating cycloadditions of nanographene and the analogous hexagonal boron nitride (h-BN) nanoflakes. Despite the C-C and B-N pairs being isoelectronic, their different ionicities give rise to their distinct response to applied electric fields. For the nanographene models, the Diels-Alder addition obeyed the reaction axis rule and the activation barrier changed under an OEEF perpendicular to the carbon skeleton for enhanced/reduced intermolecular charge transfer, which provides a feasible strategy for the side-selective derivatization of graphene to obtain one-face-only adducts and Janus bifunctional products. By contrast, for the h-BN models, the variation of the activation barrier was pronounced when the electric field was aligned along the in-plane N-B bond rather than the well-accepted reaction axis. Electronic structure analyses indicated that, because of the opposite electron withdrawing/donating nature of the reacting sites of B/N, an OEEF along the N-B bond was capable of further enhancing the polarization via in-plane intramolecular charge transfer, resulting in a stabilized transition state and notable barrier reduction.

A highly stereoregular polyphosphoester with a rigid cyclohexylene structure in the main chain was constructed via ring-opening polymerization (ROP) in the presence of an organic catalyst system. Differential scanning calorimetry (DSC) analysis indicated that isotactic polyphosphoesters exhibit a higher glass transition temperature (Tg = 9.9 °C) compared with their atactic counterparts (−20.6 °C), which are much higher than that (−60 to −40 °C) of the previously reported phosphate polymers, making these polymers have great potential in materials science.

Various photoactive building blocks can be incorporated into porous organic polymers (POPs). The intrinsic properties, such as various synthetic methods, outstanding inherent porosity, easy tunability, rigid conjugated skeletons and high stability, endow the polymeric organic networks with wonderful potential to act as heterogeneous photocatalytic platforms. However, exploitation of efficient synthetic strategies for metal-free and nontoxic heterogenous photocatalysts, and further insights into the photocatalytic process in organic transformations are still necessary. In this context, we report the concise synthesis of two polymeric frameworks (BTP-CMP and TBTP-CMP) incorporated into bithiophene and thiophthene units via a “bottom-up” strategy. BTP-CMP and TBTP-CMP were employed as heterogeneous photocatalysts in the synthesis of benzimidazoles, and exhibited excellent catalytic activity (up to 98% yield, at least 15 iterative runs). Therefore, the thiophene-embedded networks can serve as stable efficient and recyclable heterogeneous photocatalysts. Additionally, based on the catalytic results of control experiments and the energy band structures of the materials and intermediates, a possible photocatalytic reaction mechanism has been proposed.

Designing efficient electrocatalysts with optimized elements and compositions is of great significance for enhancing the performance of the electrochemical nitrogen reduction reaction (NRR). Herein...

Single-ligand-based electronically conductive porous coordination polymers/metal-organic frameworks (EC-PCPs/MOFs) fail to meet the requirements of numerous electronic applications owing to their limited tunability in terms of both conductivity and topology. In this study, a new 2D π-conjugated EC-MOF containing copper units with mixed trigonal ligands was developed: Cu3 (HHTP)(THQ) (HHTP=2,3,6,7,10,11-hexahydrotriphenylene, THQ=tetrahydroxy-1,4-quinone). The modulated conductivity (σ≈2.53×10-5 S cm-1 with an activation energy of 0.30 eV) and high porosity (ca. 441.2 m2 g-1 ) of the Cu3 (HHTP)(THQ) semiconductive nanowires provided an appropriate resistance baseline and highly accessible areas for the development of an excellent chemiresistive gas sensor.

The traditional polyvinyl alcohol composite hydrogel exhibited poor swelling and mechanical properties, which limited its application. To solve these issues, we use biomass lignin as raw material, PVA as matrix template and epichlorohydrin as cross-linker to prepare the Lignin-PVA super-absorbent hydrogels with the swelling ratio of up to 456 g/g under mild condition. When the lignin concentration was increased from vacancy to 5%, the swelling ratio of the Lignin-PVA hydrogels was increased from 92 g/g to 456 g/g. The lignin-based hydrogel synthesized by the higher molecular weight PVA showed better swelling performance. Softwood lignin, hardwood lignin and corncob lignin could also be used to fabricate the Lignin-PVA super-absorbent hydrogels with the swelling ratio of higher than 500 g/g. However, the optimum amount varied from different lignin types, which was related to the molecular weight and phenolic hydroxyl content of lignin. The structural mechanism of the Lignin-PVA hydrogel was proposed to clearly certify the enhancing role of lignin. The adsorption capacity of the Lignin-PVA hydrogel with respect to rhodamine 6G, crystal violet and methylene blue dyes was up to 196, 169 and 179 mg/g, respectively. The Lignin-PVA hydrogel presents great potential applications in the fields of soil water retention and seed cultivation in agriculture, and dye pollutant removal.

Characteristics of gas-liquid Taylor flow with different liquid viscosities are investigated in a rectangular microchannel, aiming at providing knowledge and aid in the design of processes involving viscous fluid, such as polymers and ionic liquids. The effect of liquid viscosity on the bubble formation dynamic, film thickness, bubble velocity, and pressure drop is investigated. The results reveal a specific viscous effect compared to those in square or circular channels. For the same capillary number, both the liquid film thickness at the corners and at the short planes are much larger than in square channels. New correlations are proposed for predicting the film thickness in the rectangular channel. The bubble shape sheared by the liquid phase is also distinct from literature observations that a smaller radius occurs at the rear cap. For the conditions studied (0.00065

Maternal overnutrition during pregnancy and lactation is an important risk factor for the later development of metabolic disease, especially diabetes, among mothers and their offspring. As a fructan-type plant polysaccharide, inulin has prebiotic functions and is widely used as a natural antidiabetic supplement. However, to date, the mechanism of maternal inulin treatment in the livers of offspring has not been addressed, especially with respect to long noncoding RNAs (lncRNAs). In this study, female C57BL6/J mice were fed either a high-fat diet (HFD) with or without inulin supplementation or a standard rodent diet (SD) during gestation and lactation. After the offspring were weaned, they were fed a SD for 5 weeks. At 8 weeks of age, the glucose metabolism indexes of the offspring were assessed, and their livers were collected to assay lncRNA and mRNA profiles to investigate the effects of early maternal inulin intervention on offspring. Our results indicate that male offspring from HFD-fed dams displayed glucose intolerance and an insulin resistance phenotype at 8 weeks of age. Early maternal inulin intervention improved glucose metabolism in male offspring of mothers fed a HFD during gestation and lactation. The lncRNA and mRNA profile data revealed that compared with the offspring from HFD dams, offspring from the early inulin intervention dams had 99 differentially expressed hepatic lncRNAs and 529 differentially expressed mRNAs. The differentially expressed lncRNA-mRNA coexpression analysis demonstrated that early maternal inulin intervention may change hepatic lncRNA expression in offspring; there lncRNAs are involved in metabolic pathways and the AMP-activated protein kinase signaling pathway. Importantly, the early maternal inulin intervention alleviated glucose metabolism by inhibiting the lncRNA Serpina4-ps1/let-7b-5p/Ppargc1a as a competing endogenous RNA in male offspring.

The activity of nanomaterials (NMs) in catalytically scavenging superoxide anions mimics that of superoxide dismutase (SOD). Although dozens of NMs have been demonstrated to possess such activity, the underlying principles are unclear, hindering the discovery of NMs as the novel SOD mimics. In this work, we use density functional theory calculations to study the thermodynamics and kinetics of the catalytic processes, and we develop two principles, namely, an energy level principle and an adsorption energy principle, for the activity. The first principle quantitatively describes the role of the intermediate frontier molecular orbital in transferring electrons for catalysis. The second one quantitatively describes the competition between the desired catalytic reaction and undesired side reactions. The ability of the principles to predict the SOD-like activities of metal-organic frameworks were verified by experiments. Both principles can be easily implemented in computer programs to computationally screen NMs with the intrinsic SOD-like activity., A general predicting theory for superoxide-dismutase mimicking nanomaterials is currently lacking. The present manuscript reports a density functional theory study on the superoxides dismutase-like activity of nanomaterials based on their electronic band structures and surface adsorption energies.

The utilization of malonic acids in radical decarboxylative functionalization is still underexploited, and the few existing examples are primarily limited to bisdecarboxylative functionalization. While radical monodecarboxylative functionalization is highly desirable, it is challenging because of the difficulty in suppressing the second radical decarboxylation step. Herein, we report the successful radical monodecarboxylative C–C bond coupling of malonic acids with ethynylbenziodoxolone (EBX) reagents enabled by an in situ masking strategy, affording synthetically useful 2(3H)-furanones in satisfactory yields. The keys to the success of this transformation include (1) the dual role of a silver catalyst as a single-electron transfer catalyst to drive the radical decarboxylative alkynylation and as a Lewis acid catalyst to promote the 5-endo-dig cyclization and (2) the dual function of the alkynyl reagent as a radical trapper and as an in situ masking group. Notably, the latent carboxylate group in the furanones could be readily released, which could serve as a versatile synthetic handle for further elaborations. Thus, both carboxylic acid groups in malonic acid derivatives have been well utilized for the rapid construction of molecular complexity., An in situ masking strategy has been developed based upon the unique properties of silver catalysts to successfully achieve a radical monodecarboxylative C–C bond coupling of malonic acids with ethynylbenziodoxolone reagents.

Background Waist circumference (WC) and uric acid (UA) are significantly related. Still, their temporal sequence and how the sequence works on future risk of triglyceride glucose (TyG) are unknown, especially in the Chinese population. Methods Cross-lagged panel model was used to analyze the reciprocal, longitudinal relationships among a set of interrelated variables. The mediation model was constructed to test the effect of the relationship between WC and UA on TyG. Results A total of 5727 subjects were enrolled in our study population, of which 53.5% were women, and the mean age was 59.0 (standard deviation, 8.62) years. After adjusting for traditional confounding factors, the results showed that a higher level of baseline WC was significantly associated with a higher level of follow-up UA (β = 0.003, P = 0.031) and follow-up TyG (β = 0.003, P < 0.001);. Simultaneously, there was no statistical association between the level of baseline UA and the level of follow-up WC (β = − 0.009, P = 0.951). The mediation effects of UA on WC-TyG were estimated to be 18.1% in adults, and 36.2% in women. Conclusions The current study demonstrated that higher baseline level of WC probably preceded UA’ level in general population. In addition, UA mediated the relationship of WC to TyG, especially in females. And the possible mechanism would require further clarification.

Due to the extremely high number of accessible active sites and short diffusion path, porous coordination polymer (PCP) nanosheets have demonstrated a variety of promising applications, especially for energy conversion and mass transfer. However, the development of chemically stable PCP nanosheets with dense active sites and large lateral size is a great challenge in terms of feasible considerations. Herein, we first designed and prepared a kind of chemically stable PCP nanosheets via a bottom-up and a top-down integral strategy. Featuring densely exposed and periodic Cu

The C12 specific oxidation of hydroxysteroids is an essential reaction required for the preparation of pharmaceutical ingredients like ursodeoxycholic acid (UDCA) and chenodeoxycholic acid (CDCA), which can be synthesized by Wolff-Kishner reduction of the obtained 12-oxo-hydroxysteroids. 12α-hydroxysteroid dehydrogenases (12α-HSDHs) have been shown to perform this reaction with high yields, under mild conditions and without the need of protection and deprotection steps, required in chemical synthesis. Here, the recombinant expression and biochemical characterization of the nicotinamide adenine dinucleotide (NAD + )-dependent HSDH from Eggerthella lenta (El12α-HSDH) are reported. This enzyme shows comparable properties with the well-known nicotinamide adenine dinucleotide phosphate (NADP + )-dependent enzyme from Clostridium sp. 48–50. In order to perform a viable and atom efficient enzymatic hydroxysteroid oxidation, NAD(P)H oxidase (NOX) was employed as cofactor regeneration system: NOX uses oxygen (O 2 ) as sacrificial substrate and produces only water as side product. 10 mM of cholic acid was fully and selectively converted to 12-oxo-CDCA in 24 h. The possibility to employ this system on UCA and 7-oxo-deoxycholic acid (7-oxo-DCA) as substrates was additionally investigated. The performance of the El12α-HSDH was evaluated also in combination with a “classical” regeneration system (oxaloacetate/malate dehydrogenase) showing full conversion in 4 h. Finally, the feasibility of a catalytic aerobic-NAD + -dependent enzymatic oxidation was shown on a preparative scale (oxidation of CA to 12-oxo-CDCA) employing the El12α-HSDH-NOX system in a segmented-flow-reactor. (Figure presented.).

Flexibility in gas absorption Soft materials such as porous coordination polymer (PCP) can exhibit temperature-dependent flexible motions of their internal pores that can assist in gas separation and storage. Gu et al. designed a copper-based PCP with a ligand that contains phenothiazine-5,5-dioxide. The entrances to the porous cages changed size with temperature, when these functional groups underwent flipping motions. The change in gate size could lead to high selectivity for gas absorption and enabled the separation of oxygen from argon and of ethylene from ethane as well as long-term gas storage under ambient conditions. Science , this issue p. 387

High-level expression of β-mannanase has been reported in Pichia pastoris under control of the GAP promoter. Two factors that strongly influence protein production and fermentation process development in Pichia pastoris protein expression system are gene dosage and cultivation temperature. The aim of this research was to improve the expression level of β-mannanase in Pichia pastoris by proper increasing the gene dosage and decreasing the culture temperature. To this end, a panel of strains harboring different copy numbers of β-mannanase gene were obtained by multiple zeocin concentration gradients screening, the influence of gene copy number on the expression of β-mannanase in Pichia pastoris X33 was investigated. With the constitutive GAP promoter, the four copies strain exhibited a 4.04-fold higher β-mannanase yield and a 1.83-fold higher total secretion proteins than the one copy strain, but an increase of the copy number above four resulted in a decrease of expression. Furthermore, the effects of culture temperature were studied in flask. The decreased culture temperature of four copies strain resulted in a 1.8-fold (26 °C) and 3.5-fold (22 °C) higher β-mannanase activity compared to that at 30 °C. A fed-batch strategy was successfully used for high cell-density fermentation and β-mannanase activity reached 2124 U/mL after cultivation for 72 h in a 5 L fermenter.

A three-dimensional graphene aerogel-supported Ir (Ir/GA) nanocomposite with interconnected porous framework and high dispersion of Ir nanoparticles is synthesized via a simple yet effective “co-reduction self-assembly” strategy, in which the chemical co-reduction of graphene oxide and H2IrCl6 occurs in the presence of glycerol and Ir is directly incorporated onto the reduced graphene oxide nanosheets. The Ir/GA possesses rich hierarchical porosity, a low amount of oxygen-containing functional groups, and a certain amount of Irδ- species, which notably improve the accessibility to both sides of the resulting reduced graphene oxide nanosheets, number of active Ir sites, electron transfer ability, and affinity of active Ir with C O band. As a catalyst in chemoselective cinnamaldehyde (CMA) hydrogenation towards cinnamyl alcohol (CMO), the Ir/GA shows satisfactory CMA conversion of 85.8% and CMO selectivity of 83.2% with a high TOF activity of yielding CMO up to 17.5 h−1 at reaction time of 1 h. Moreover, the Ir/GA delivers good catalytic durability even after seven successive cycles without pronounced activity deterioration. This study highlights the exciting possibility to synthesize highly efficient graphene-supported precious metal catalysts with multiscale control by overall consideration in mass transportation, metal dispersion, metal-support interactions, and electronic density of active sites for chemoselective CMA hydrogenation.

Adverse early-life exposures program an increased risk of chronic metabolic diseases in adulthood. However, the effects of genistein consumption in early life on metabolic health are unclear. Our objective was to investigate whether perinatal genistein intake could mitigate the deleterious effects of a high-fat diet (HF) on metabolism in dams and female offspring and to explore the role of the gut microbiota in mediating the transgenerational effects. C57BL/6 female mice were fed a HF, HF with genistein (0.6 g kg-1 diet) or normal control diet for 3 weeks before mating and throughout pregnancy and lactation. The offspring had free access to normal diet from weaning to 24 weeks of age. A glucose tolerance test was performed and the levels of serum insulin and lipid were measured. The cecal contents were collected for 16s rDNA sequencing. The results showed that perinatal genistein intake could not only significantly reduce blood glucose levels, insulin and free fatty acids (FFA) in dams, but also improve glucose tolerance, insulin sensitivity and serum lipid profiles in adult female offspring. Significant enrichment of short-chain fatty acid (mainly butyrate)-producing bacteria might play crucial roles in deciphering the metabolic benefits of perinatal genistein intake in dams. The obvious decrease in harmful microorganisms and increase in Erysipelotrichaceae_incertae_sedis were associated with the protective effects of maternal genistein intake on female offspring. In addition, Bifidobacterium might be an important factor for deciphering the metabolic improvement in both dams and female offspring by dietary genistein. Overall, perinatal genistein intake attenuated the harmful effects of HF on metabolism in both dams and female offspring, and the protective effects were associated with the alterations in the gut microbiota, which provides new evidence and targets for mitigating the poor effects of adverse early-life exposures on metabolic health in later life.

A novel squaramide-containing metal-organic framework (MOF) material has been designed and synthesized. A detailed X-ray crystal structure analysis showed that four squaramides of this MOF adopted two orientations in each dependent nanopore, confirming that two carbonyl and two N-H groups pointed simultaneously to the inside of the one-dimensional nanometer channel. The MOF was applied as an efficient bifunctional hydrogen-bonding catalyst for Michael additions of 1,3-dicarbonyl compounds to nitroalkenes in pure water, boosting the catalytic efficiency by up to approximately five times the value afforded by the homogeneous control and exhibiting a highly size-selective catalytic performance and good renewability. The catalytic mechanism was also discussed in detail. The present study provides a highly promising approach to achieving dual-activation catalytic centers in a single system, which function as microscopic chemical reactors that allow the interaction and fast transport of substrate molecules in their cavities.

Iron-catalyzed direct amination of aliphatic C(sp3)–H bonds developed by Betley et al. (Science, 2013, 340, 591–595) is an efficient synthetic method to access a range of substituted pyrrolidines. Herein, we conducted density functional theory (DFT) calculations to explore the mechanism and origins of regioselectivity of this remarkable C(sp3)−H amination using an iron-dipyrrinato catalyst. Computational results show that iron-catalyzed C(sp3)–H amination occurs via the following phases: (a) ligand–substrate exchange offering the active Fe(II) catalyst; (b) oxidation of the Fe(II) catalyst to an Fe(III)-nitrene radical species using the alkyl azide substrate with the release of N2 molecules; (c) intramolecular H-abstraction (C⋯H⋯N) affording an alkyl radical and an Fe(III)-iminyl radical; and (d) radical rebound leading to a N-heterocyclic compound, which reacts with Boc2O to avoid product inhibition via a highly exergonic reaction affording an N-protected amine and regenerates the active Fe(II) catalyst by coordination with another alkyl azide substrate. Owing to the effortless nature of the radical rebound process, the calculations reveal that the H-abstraction step determines the regioselectivity of amination, with which arising mainly from a combination of radical stability and ring strain. The results demonstrate rich experimental–theoretical synergy and provide useful insights for further development of site-selective C–H functionalization reactions.

This study aimed to establish the role of miR-129 and miR-384-5p in cerebral ischemia-induced apoptosis. Using PC12 cells transfected with miR-129 or miR-384-5p mimics or inhibitors, oxygen glucose deprivation (OGD) conditions were applied for 4 h to simulate transient cerebral ischemia. Apoptotic phenotypes were assessed via lactate dehydrogenase (LDH) assay, MTT cell metabolism assay, and fluorescence-activated cell sorting (FACS). The effect of miR overexpression and inhibition was evaluated by protein and mRNA detection of bcl-2 and caspase-3, critical apoptosis factors. Finally, the direct relationship of miR-129 and bcl-2 and miR-384-5p and caspase-3 was measured by luciferase reporter assay. The overexpression of miR-384-5p and miR-129 deficiency significantly enhanced cell viability, reduced LDH release, and inhibited apoptosis. By contrast, overexpression of miR-129 and miR-384-5p deficiency aggravated hypoxia-induced apoptosis and cell injury. miR-129 overexpression significantly reduced mRNA and protein levels of bcl-2 and miR-129 inhibition significantly increased mRNA and protein levels of bcl-2 in hypoxic cells.miR-384-5p overexpression significantly reduced protein levels of caspase-3 while miR-384-5p deficiency significantly increased protein levels of caspase-3. However, no changes were observed in caspase-3 mRNA in either transfection paradigm. Finally, luciferase reporter assay confirmed caspase-3 to be a direct target of miR-384-5p; however, no binding activity was detected between bcl-2 and miR-129.Transient cerebral ischemia induces differential expression of miR-129 and miR-384-5p which influences apoptosis by regulating apoptotic factors caspase-3 and bcl-2, thereby participating in the pathological mechanism of cerebral ischemia, and becoming potential targets for the treatment of ischemic cerebral injury in the future.

Pectin nanofiber mats prepared with periodate oxidation–electrospinning–adipic acid dihydrazide crosslinking strategy are promising for biomedical applications. In this study, we systematically examined the effects of electrospinning and crosslinking conditions on the properties of pectin nanofiber mats. The properties of mats were tunable in the range of 200–400 nm fiber size, 11–21% ADH residue content, 13–28 times absorbency, 13°–21° contact angle, 2 weeks or longer degradation time, 1.5–2.2 MPa tensile strength, 40–70% elongation, and 0.25–0.27 g/(cm2·24 h) permeability. Increasing polymer concentration, adipic acid dihydrazide amount, time or temperature could increase fiber size and its tensile strength, and decrease the absorbency, hydrophilicity, degradation rate, and elongation. These results indicate that controlling the process parameters can effectively regulate the properties of pectin nanofiber mats and meet the requirements of various biomedical applications.

Diabetic nephropathy is a severe microvascular complication of diabetes. Qishen Yiqi dripping pill (QYDP) has been reported to be a renal protective drug. However, the mechanisms remain unclear. This study was performed to investigate the mechanisms. In this study, Sprague-Dawley rats were injected with streptozotocin to generate a diabetes model. Diabetic rats were administered 150 or 300 mg/kg/day QYDP. After 8 weeks of treatment, serum creatinine, serum blood urea nitrogen, and 24-h urinary albumin were measured. Kidney histological staining and immunostaining were analyzed. Then, the renal tissue was analyzed with a genome expression array. The results showed that QYDP treatment reduced serum creatinine, blood urea nitrogen, and 24-h urinary albumin and improved kidney histology and fibrosis. The gene array revealed that the expression of 189 genes was increased, and that of 127 genes was decreased in the high dosage QYDP group compared with the diabetic group. Pathway and gene ontology analyses showed that the differentially expressed genes were involved in the Wnt/β-catenin and transforming growth factor-β (TGF-β)/Smad2 signaling pathways. QYDP reduced the renal Wnt1, catenin β1, Tgfb1, and Smad2 gene expression and β-catenin, TGF-β, Smad2, collagen I, α-smooth muscle actin, and fibronectin protein expression in diabetic rats. Our results provide the first evidence that QYDP performs its renal-protective function by inhibiting the Wnt/β-catenin and TGF-β/Smad2 signaling pathways in diabetic rats.

Amorphous silicon carbide (SiC) thin films can be applied as window layers for perovskite solar cells, where low processing temperature and ion-bombardment free is favorable. By taking advantages of the e-beam evaporation technique, amorphous SiC thin films were deposited at room temperature in this work. The dependency of e-beam current in material composition was investigated, as well as the conductivity and optical bandgap. It is shown that SiC films consist of Si-O component and its ratio can be tuned from 57.5% to 10.0% by controlling the e-beam current from 38 mA to 78 mA. The C C component tends to form at e-beam current more than 58 mA. By adjusting the Si-O and C C components, amorphous SiC thin films with optical bandgap of 1.7–2.3 eV and conductivity of 10−6–10−4 S/cm were obtained with e-beam current of 38–52 mA, which possesses a good potential for applications in solar cells.

Based on previous reports，toll-like receptors (TLRs) are recognition molecules common in various aquatic animals and play a vital role in innate immunity. In this study, a novel TLR CgToll-3 with leucine-rich repeats (LRRs) and a TIR (Toll-interleukin 1-resistance) domain was cloned in Crassostrea gigas. CgToll-3 with sixteen potential extracellular N-linked glycosylation sites and shares the closest phylogenic relationship with molluscan TLRs. Alignment of LRRs and TIR domains indicated that CgToll-3 was highly conserved compared to other LRRs of mollusks which could respond against Vibrio or other bacterial molecules, and contained three conserved functionally important motifs (Box 1, Box 2, and Box 3). The Hex Molecular Docking result showed that CgToll-3 could interact with CgMyd88 via the TIR domain. Subcellular Co-localization and BiFC Assay confirmed this interaction, and they could induce NF-κB activation. CgToll-3 was moderately expressed in the digestive gland, and its expression level was significantly up-regulated after Vibrio alginolyticus challenge. Taken together, CgToll-3 might be involved in the innate immune response to V. alginolyticus for C. gigas through a MyD88-dependent TLR mediated signaling pathway.

BACKGROUND: Monomorphic epitheliotropic intestinal T cell lymphoma (MEITL) is a rare extra-nodal T-cell lymphoma that has uniformly aggressive features with a poor prognosis. No standardized treatment protocols have been established. Previous experience has demonstrated favorable outcomes with combination chemotherapy followed by autologous hematopoietic stem cell transplant. However, many patients are unable to tolerate the toxicities. Chidamide is a new histone deacetylase inhibitor that has shown preferential efficacy in mature T-cell lymphoma. CASE SUMMARY: We herein present two cases of MEITL who were both intermediate risk according to enteropathy-associated T cell lymphoma prognostic index. Case one was a 61-year-old man. He complained of upper abdominal pain and intermittent black stool for 2 mo. Imaging examination revealed that the intestinal wall was thickened. He received a partial excision of the small intestine. A chidamide-based combination regimen was given postoperatively. Eleven months later, he presented with recurrence in the bilateral lungs. He passed away 15 mo after his diagnosis. Case two was a 35-year-old woman who complained of abdominal distention for 1 mo. Positron emission tomography/computed tomography demonstrated wall thickening of the small intestine and upper sigmoid colon. Colon perforation and septic shock occurred on the fourth day of her admission. She was treated by sigmoid colostomy. Chidamide-based combination therapy was then provided. She was recurrence-free for 6 mo until lesions were found in the bilateral brain and lived for 17 mo since her diagnosis. Compared to historical data, chidamide seems to improve the prognosis of MEITL slightly. CONCLUSION: MEITL is a type of aggressive lymphoma. Chidamide is a new promising approach for the treatment of MEITL.

To achieve unique molecular-recognition patterns, a rational control of the flexibility of porous coordination polymers (PCPs) is highly sought, but it remains elusive. From a thermodynamic perspective, the competitive relationship between the structural deformation energy (Edef ) of soft PCPs and the guest interaction is key for selective a guest-triggered structural-transformation behavior. Therefore, it is vital to investigate and control Edef to regulate this competition for flexibility control. Driven by these theoretical insights, we demonstrate an Edef -modulation strategy via encoding inter-framework hydrogen bonds into a soft PCP with an interpenetrated structure. As a proof of this concept, the enhanced Edef of PCP enables a selective gate-opening behavior toward CHCl3 over CH2 Cl2 by changing the adsorption-energy landscape of the compounds. This study provides a new direction for the design of functional soft porous materials.

Scope: As a prebiotic, inulin may have a protective effect on glucose metabolism. However, the mechanism of inulin treatment on glucose intolerance in offspring exposed to a maternal high-fat diet is still not clear. Here, we examined the hepatic DNA methylation profile to determine how maternal inulin supplementation modified glucose metabolism in offspring mice. Procedures: Female mice were fed a high-fat (HF) diet, control diet (CON) or a high-fat diet with inulin supplementation (HF-inulin) during gestation and lactation. Upon weaning, pup livers were obtained. A hepatic genome DNA methylation array was performed. Results: Pups exposed to a maternal HF diet exhibited glucose intolerance and insulin resistance. Maternal inulin treatment moderated glucose metabolism. A DNA methylation array identified differentially methylated regions associated with 970 annotated genes from pups exposed to a HF diet in response to maternal inulin treatment. In particular, the wingless-type MMTV integration site family member 5A (Wnt5a) gene was hypermethylated, and the phosphatidylinositol-4-phosphate 3-kinase catalytic subunit type 2 alpha (Pik3c2a), phosphatidylinositol-4-phosphate 3-kinase catalytic subunit type 2 beta (Pik3c2b), and phosphoinositide-3-kinase regulatory subunit 2 (Pik3r2) genes were hypomethylated in inulin-treated pups. Consistently, hepatic Wnt5a gene expression was reduced and Pik3c2a, Pik3c2b, and Pik3r2 gene expression was increased in the inulin group. Conclusion: Maternal inulin treatment improved glucose intolerance by changing DNA methylation and gene expression of Wnt5a and Pi3k in mice exposed to a maternal HF diet.

A novel palladium-catalyzed alkene diacetoxylation with dioxygen (O2) as both the sole oxidant and oxygen source is developed, which was identified by 18O-isotope labeling studies. Control experiments suggested that bis(pinacolato)diboron (B2pin2) played a dominant intermediary role in the formation of a C–O bond. This method performed good functional group tolerance with moderate to excellent yields, which could be successfully applied to the late-stage modification of natural products. Furthermore, an atmospheric pressure of dioxygen enhances the practicability of the protocol.

Density functional theory computations have elucidated the detailed mechanism and intriguing selectivities of C(sp3)–H activation and arylation of aldehydes and ketones promoted by palladium–amino acid cooperative catalysis. The amino acid cocatalyst takes up the carbonyl substrate by a condensation reaction to form an imine–acid, which acts as a transient directing reagent and metathesizes with Pd(OAc)2 (the precatalyst) to initiate active Pd(II) complexes. The reaction then proceeds through C–H bond activation, oxidative addition of Pd(II) by iodobenzene, and reductive elimination from Pd(IV) completing C–C bond formation, followed by ligand exchange to regenerate the active Pd(II) catalyst and release the arylated imine–acid which continues on hydrolysis to give the final product and regenerate the amino acid cocatalyst. The C–H activation step via concerted metalation–deprotonation (CMD), which is rate- and selectivity-determining, favors palladacyclic transition states with a minimum chelate ring str...

A straightforward approach for the assembly of different polysubstituted propiolamidnates via palladium-catalyzed multicomponent reaction of isocyanides, haloalkynes, and amines has been reported in which the C(sp)-C(sp2) and C(sp2)═N bonds were constructed in one pot. This reaction featured in high efficiency, excellent chemoselectivity, and good functional group compatibility. The synthetic utility of this method was also demonstrated.

Scope: Maternal obesity leads to glucose intolerance in the offspring. Changes in the gut microbiota are being increasingly implicated in the pathogenesis of diabetes. We hypothesized that inulin intervention during gestation and lactation improves glucose metabolism disorders in mouse offspring from high-fat diet (HD)-fed dams. Procedures: Female C57BL mice were fed a control diet or HD for 4 weeks before mating. After mating, pregnant mice were randomly divided into three groups through gestation and lactation: control diet (CD) group, HD group, and HD treated with inulin (HD-inulin) group. At weaning, glucose metabolic status was assessed. Gut microbial DNA from offspring cecal contents was isolated and processed for metagenomic shotgun sequencing, and taxonomic and functional profiling were performed. Results: Offspring from dams in the HD-inulin groups demonstrated reduced fasting blood glucose, decreased blood glucose area under the curve during the oral glucose tolerance test, and reduced fasting serum insulin and HOMA-IR compared to offspring from dams in the HD group. Nineteen differentially abundant bacterial species were identified between the HD-inulin and HD groups. The HD-inulin group displayed significantly greater abundances of Bacteroides_acidifaciens, Eubacterium_sp_CAG_786, Clostridium_sp_CAG_343, and Bifidobacterium_breve species and lower abundances of Oscillibacter_sp_1_3, Ruminococcus_gnavus_CAG_126, and Bacteroides_massiliensis species. Differentially abundant bacterial species among the three groups were involved in 38 metabolic pathways, including several glucose and lipid metabolism pathways. Conclusion: Our results show that early inulin intervention in HD-fed mouse dams moderates offspring glucose metabolism and gut dysbiosis.

Magnetic mesoporous silica nanospheres (MMSN) were prepared and the surface was modified with cancer cell-specific ligand folic acid. Calcium carbonate was then employed as acid-activated gatekeepers to cap the mesopores of the MMSN, namely, MMSN-FA-CaCO3. The formation of the MMSN-FA-CaCO3 was proved by several characterization techniques, viz. transmission electron microscopy, zeta potential measurement, Fourier transform infrared spectroscopy, BET surface area measurement, and UV–Vis spectroscopy. Daunomycin was successfully loaded in the MMSN-FA-CaCO3 and the system exhibited sensitive pH stimuli-responsive release characteristics under blood or tumor microenvironment. Cellular uptake by folate receptor (FR)-overexpressing HeLa cells of the MMSN-FA-CaCO3 was higher than that by non-folated-conjugated ones. Intracellular-uptake studies revealed preferential uptake of these nanoparticles into FR-positive [FR(+)] HeLa than FR-negative [FR(-)]A549 cell lines. DAPI stain experiment showed high apoptotic rate of MMSN-FA-DNM-CaCO3 to HeLa cells. The present data suggest that the CaCO3 coating and folic acid modification of MMSN are able to create a targeted, pH-sensitive template for drug delivery system with application in cancer therapy.

Developing an efficient non-noble bifunctional electrocatalyst for both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) in the same electrolyte is significant for lowering the cost of electrochemical water splitting. Herein, a phase-pure pentlandite Ni4.3Co4.7S8 bifunctional electrocatalyst was synthesized via a hydrothermal process using a commercial nickel foam as the nickel source. The active metallic nickel source and the chelating agent ethylenediamine play important roles in the formation of phase-pure pentlandite Ni4.3Co4.7S8 binary sulfide. Physicochemical characterizations, electrochemical measurements and density functional theory (DFT) computations illustrate that the material has an exposed high-indexed (022) surface with a biomimetic hydrogenase-like structure, and that the pentlandite phase has metallic characteristics, with next-nearest neighbor metal–metal bonds, as well as there being a high overlap of density of state (DOS) at the Fermi-level due to the synergistic effect between Ni and Co ions. In addition, there is an elevation of the d-state center (from −2.84 to −1.52 eV) with high occupation of the anti-bonding eg (dx2−y2 and dz2) d-orbitals. These properties endow the Ni4.3Co4.7S8 bifunctional electrocatalyst with higher catalytic activity for OER than RuO2, with comparative activity for HER to commercial Pt/C and with a low over-potential for all water splitting in an alkaline electrolyte. The studies here provide a novel strategy to synthesise phase-pure pentlandite nickel cobalt binary sulfides and boost their applications in electrochemical water splitting.

Honokiol is a bioactive biphenolic component derived from Magnoliae officinalis Cortex (known as “Hou Po” in Chinese), a traditional Chinese herbal medicine. A series of novel 1,3,4-thiadiazole/oxadiazole-linked honokiol derivatives were synthesized and tested for anticancer activity against seven human cancer cell lines in this study. Among all derivatives, 8a had the most potent cytotoxic effect on all tested cancer cells, with IC50 values ranging from 1.62 ± 0.19 to 4.61 ± 0.51 µM, which were 10.38–34.36 folds more potent than the parental honokiol (IC50 values of 30.96 ± 1.81–55.67 ± 0.31 µM). On A549, HCT116, and MDA-MB-231 cell lines, 8a demonstrated 5.69-fold, 5.65-fold, and 4.83-fold greater cytotoxicity than cisplatin, respectively. Compound 8a also had higher selectivity (SI values of 8.41–49.38) towards seven cancer cell lines over the normal cell lines than cisplatin (SI values of 1.24–2.52). The analysis of structure–activity relationships (SARs) revealed that honokiol derivatives bearing 1,3,4-thiadiazoles (8a-j) possessed stronger anticancer activity than those containing 1,3,4-oxadiazoles. Further mechanistic investigation indicated that 8a induced cytotoxic autophagy in cancer cells in a time- and dose-independent manner via suppressing the PI3K/Akt/mTOR pathway. Molecular docking suggested that 8a could bind to the PI3Kα active sites. Additionally, 8a inhibited the migration and invasion of A549 and MDA-MB-231 cancer cells.

Here we report a soft porous crystal possessing hemilabile cross-links in its framework that exhibits exclusive gate opening for ethylene, enabling the discriminatory adsorption of ethylene over ethane. A Co-based porous coordination polymer (PCP) bearing vinylogous tetrathiafulvalene (VTTF) ligands, [Co(VTTF)], forms Co-S bonds as intermolecular cross-links in its framework in the evacuated closed state. The PCP recognizes ethylene via d-π complexation on the accessible metal site that displaces and cleaves the Co-S bond to "unlock" the closed structure. This ethylene-triggered unlocking event facilitates remarkable nonporous-to-porous transformations that open up accessible void space. This structural transformation follows a two-step gate-opening process. Each phase, including the intermediate structure, was successfully characterized by single-crystal X-ray diffraction analysis, which revealed an intriguing "half-open" structure suggestive of a disproportionate gate-opening phenomenon. The gate-opening mechanism was also investigated theoretically; density functional theory and Monte Carlo calculations revealed that the unique "half-open" phase corresponds to a substantially stable intermediate over the possible transformation trajectories. While ethylene opens the gate, ethane does not because it is unable to coordinate to the Co center. This feature is maintained even at pressures above 1 MPa and at a temperature of 303 K, demonstrating the potential of the "gate-locking/unlocking" mechanism that exploits the hemilabile cross-linking in soft porous crystals.

A novel and convenient palladium catalytic system for the synthesis of α-amino acid esters from simple starting materials is reported. Hydrogen peroxide not only acts as the green oxidant, but also as the oxygen source. This strategy for the conversion of amines and vinyl ethers into highly functionalized and structurally diverse α-amino acid esters is characterized by the simplicity of the experimental procedure, mild reaction conditions, high atom economy, scalability, and practicability.

Epithelial brush-border membrane vesicles (BBMVs) were isolated from the intestine of common carp and studied systematically by enzyme activity, transmission electron microscopy and immunoblotting. The uptake time course and the substrate concentration effect were assessed, and then, the ability of phlorizin and cytochalasin B to inhibit uptake was analyzed. The results show that sucrase, alkaline phosphatase and Na+-K+-ATPase activities in these vesicles were enriched 7.94-, 6.74- and 0.42-fold, respectively, indicating a relatively pure preparation of apical membrane with little basolateral contamination. The vesicular structure was in complete closure, as confirmed by electron microscopy. The presence of SGLT1 on the BBMVs was confirmed by Western blot analysis. In the time course experiment, the glucose uptake by BBMVs in Na+ medium displayed an initial accumulation (overshoot) at 5 min followed by a rapid return to equilibrium values at 60 min. Over the 2-NBDG concentration range selected, the external 2-NBDG concentration in NaSCN medium graphed as a curved line. Phlorizin and cytochalasin B had an obvious inhibitory effect on 2-NBDG transport in carp BBMVs, and the detected fluorescence intensity decreased. The inhibition rate in the 1000 μM group was the strongest at 64.18% and 63.61% of phlorizin and cytochalasin B, respectively, indicating the presence of carriers other than SGLT1. This study is the first to demonstrate that 2-NBDG can be used as a convenient and sensitive probe to detect glucose uptake in fish BBMVs. This technology will provide a convenient method to discover new effects and factors in glucose metabolism.

Electrochemical surface-enhanced Raman spectroscopy (EC-SERS) can provide the fingerprint information at the molecular level during electrochemical processes and the laser used in the EC-SERS process can simultaneously induce the plasmon-mediated chemical reaction (PMCR). In this work, EC-SERS has been used to understand the plasmonic effects on the selective dimerization reduction route of para-halonitrobenzene on the AgNPs@Ag electrode. Para-iodonitrobenzene (pINB) was first chosen as the probe molecule for photoelectrochemical reductions and investigated in acidic and neutral electrolyte solutions. The density functional theory (DFT) calculations confirmed that the electrochemical reduction of pINB produces 2-amino-5-iodophenol in HClO4 and p,p’-diiodoazobenzene (DIAB) in neutral electrolyte. However, when the PMCR is introduced in the electroreduction of pINB, the route of reduction path can be altered to the reduction product DIAB. Thus DIAB was generated firstly both in acidic and neutral conditions by PMCR and then reduced to p-iodoaniline. Finally, all the para chloro- and bromo- nitrobenzene can generate the p,p’-dihalo-azobenzene dimer by the PMCR under acidic conditions. Therefore, the plasmonic photoelectrochemical dimerization and reduction reactions can give us an idea to introduce the light on the selectivity of chemical reactions on plasmonic noble electrodes of nanostructures to alter the reduction pathway. This is practically significant for obtaining highly selective reduction products.

The 2019 coronavirus disease (COVID-19) caused by SARS-CoV-2 virus infection has posed a serious danger to global health and the economy. However, SARS-CoV-2 medications that are specific and effective are still being developed. Honokiol is a bioactive component from Magnoliae officinalis Cortex with damp-drying effect. To develop new potent antiviral molecules, a series of novel honokiol analogues were synthesized by introducing various 3-((5-phenyl-1,3,4-oxadiazol-2-yl)methyl)oxazol-2(3H)-ones to its molecule. In a SARS-CoV-2 pseudovirus model, all honokiol derivatives were examined for their antiviral entry activities. As a result, 6a and 6p demonstrated antiviral entry effect with IC50 values of 29.23 and 9.82 µM, respectively. However, the parental honokiol had a very weak antiviral activity with an IC50 value more than 50 µM. A biolayer interfero-metry (BLI) binding assay and molecular docking study revealed that 6p binds to human ACE2 protein with higher binding affinity and lower binding energy than the parental honokiol. A competitive ELISA assay confirmed the inhibitory effect of 6p on SARS-CoV-2 spike RBD’s binding with ACE2. Importantly, 6a and 6p (TC50 > 100 μM) also had higher biological safety for host cells than honokiol (TC50 of 48.23 μM). This research may contribute to the discovery of potential viral entrance inhibitors for the SARS-CoV-2 virus, although 6p’s antiviral efficacy needs to be validated on SARS-CoV-2 viral strains in a biosafety level 3 facility.

Backgrounds Osteoarthritis (OA) is an orthopedic inflammatory disease which can cause functional disability and chronic pain. MiRNAs are known to play important roles in OA. To identify the targets for the treatment of OA, bioinformatics analysis was performed to explore differentially expressed miRNAs between OA and normal samples. Methods Bioinformatics analysis was conducted to identify differentially expressed miRNAs. To mimic OA in vitro, primary chondrocytes were stimulated with IL-1β. Meanwhile, flow cytometry was performed to detect the cell apoptosis and cycle distribution. In addition, protein and mRNA expressions were detected by Western blot and RT-qPCR, respectively. Finally, in vivo model of OA was constructed to investigate the function of miR-892b in OA. Results The data indicated that miR-892b was identified to be upregulated in OA samples. Additionally, miR-892b antagomir markedly reversed IL-1β-induced growth decline of chondrocytes via inhibiting the apoptosis. IL-1β notably elevated the expressions of MMP1 and MMP13 and downregulated the level of Aggrecan in chondrocytes, while miR-892b antagomir reversed these phenomena. Meanwhile, cyclin D1 and cyclin D2 were the direct targets of miR-892b. In addition, IL-1β-induced G1 phase arrest in chondrocytes was partially abolished by of miR-892b antagomir. In vivo study indicated miR-892b antagomir could significantly alleviate the symptom of OA in a rat model. Conclusion MiR-892b antagomir inhibits the progression of OA via targeting Cyclin D1 and Cyclin D2. Thus, our finding might supply a novel target for OA treatment.

Adsorptions of CO, N2, NO, and CO2 in a paddle-wheel-type porous coordination polymer (PCP) [Cu(aip)]n (aip = 5-azidoisophthalate) were investigated with ONIOM[MP4(SDQ):ωB97XD] method using a model system consisting of two [Cu2(O2CC6H4-R)4] units (R = H and Me) and one [Cu2(O2CC6H4–R)4] unit, namely, dimer and monomer models. The experimental CO adsorption position was reproduced well by the present calculation with the dimer model. For adsorptions of CO, N2, NO, and CO2 in the dimer model, the position of gas molecule deviates from the normal one that is found in the monomer model and becomes more distant from the surrounding phenyl group(s) of the neighbor [Cu(aip)] unit. For all of these gas molecules, the calculated binding energy (BE) at the deviating adsorption position is larger than that at the normal one against our expectation that the normal position is the best for the gas adsorption. The deviation of gas adsorption position arises from the interaction between the organic linker (O2CC6H4–R moi...

The prevalence of the condensed phase, interpenetration, and fragility of ruesoporous coordination polymers (meso-PCPs) featuring dense open metal sites (OMSs) place strict limitations en their preparation, as revealed by experimental and `theoretical reticular chemistry investigations. Herein, we propose a rational design of stabilized high-porosity meso-PCPs, employing a `low-symmetry ligand in combination with the shortest linker, formic acid. The resulting dimeric dusters (PCP-31 and PCP-32) exhibit high surface areas, ultrahigh porosities, and high OMS derisities (3.76 and 3.29 nmol g(-1) respectively), enabling highly selective- and effective separation of C2H2 from C2H2/CO2 mixtures at 298 K, as verified by binding energy (BE) and electrostatic potentials (ESP) calculations.

Although the existence of Stone–Wales (5-7) defect at graphene edge has been clarified experimentally, theoretical study on the formation mechanism is still imperfect. In particular, the regioselectivity of multistep reactions at edge (self-reconstruction and growth with foreign carbon feedstock) is essential to understand the kinetic behavior of reactive boundaries but investigations are still lacking. Herein, by using finite-sized models, multistep reconstructions and carbon dimer additions of a bared zigzag edge are introduced using density functional theory calculations. The zigzag to 5-7 transformation is proved as a site-selective process to generate alternating 5-7 pairs sequentially and the first step with largest barrier is suggested as the rate-determining step. Conversely, successive C2 insertions on the active edge are calculated to elucidate the formation of 5-7 edge during graphene growth. A metastable intermediate with a triple sequentially fused pentagon fragment is proved as the key structure for 5-7 edge formation. © 2017 Wiley Periodicals, Inc.

Recently, the oxidative functionalization of double-fused-pentagon (DFP)-containing chlorofullerenes #271C50Cl10 and #913C56Cl10 was carried out, resulting in two monoepoxides with the oxygen atom added at the ortho site of pentalene on the DFP moiety. To uncover the reactivity of isolated-pentagon-rule violating fullerenes upon oxidation, two possible formation processes (ozone molecule and oxygen radical served as oxidation reagents) of these two oxides were systematically investigated through density functional theory calculations. For the ozone oxidation, two possible pathways were explored, and the results indicate that the biradical mechanism Pathos-RACDP is kinetically more favorable than Pathos-RABP, where R, A, and P represent reactants, ozonide intermediates, and oxidation products and B, C, and D represent another three oxygen-containing intermediates. The products obtained by ozone oxidation ([6,6]-55-closed epoxides P–C3–C29 for #271C50Cl10 and P–C42–C43 for #913C56Cl10 with oxygen atom added...

Metformin (MET) is the first-line drug for treating type 2 diabetes mellitus (T2DM). However, MET increases blood lactate levels in patients with T2DM. Lactate possesses proinflammatory properties and causes insulin resistance (IR). Oxamate (OXA), a lactate dehydrogenase inhibitor, can decrease tissue lactate production and blood lactate levels. This study was conducted to examine the effects of the combination of OXA and MET on inflammation, and IR in diabetic db/db mice. Supplementation of OXA to MET led to lowered tissue lactate production and serum lactate levels compared to MET alone, accompanied with further decreased tissue and blood levels of pro-inflammatory cytokines, along with better insulin sensitivity, beta-cell mass, and glycemic control in diabetic db/db mice. These results show that OXA enhances the anti-inflammatory and insulin-sensitizing effects of MET through the inhibition of tissue lactate production in db/db mice.