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Keratin (KRT), a natural fibrous structural protein, can be classified into two categories: "soft" cytosolic KRT that is primarily found in the epithelia tissues (e.g., skin, the inner lining of digestive tract) and "hard" KRT that is mainly found in the protective tissues (e.g., hair, horn). The latter is the predominant form of KRT widely used in biomedical research. The oxidized form of extracted KRT is exclusively denoted as keratose (KOS) while the reduced form of KRT is termed as kerateine (KRTN). KOS can be processed into various forms (e.g., hydrogel, films, fibers, and coatings) for different biomedical applications. KRT/KOS offers numerous advantages over other types of biomaterials, such as bioactivity, biocompatibility, degradability, immune/inflammatory privileges, mechanical resilience, chemical manipulability, and easy accessibility. As a result, KRT/KOS has attracted considerable attention and led to a large number of publications associated with this biomaterial over the past few decades; however, most (if not all) of the published review articles focus on KRT regarding its molecular structure, biochemical/biophysical properties, bioactivity, biocompatibility, drug/cell delivery, and in vivo transplantation, as well as its applications in biotechnical products and medical devices. Current progress that is directly associated with KOS applications in tissue regeneration and drug delivery appears an important topic that merits a commentary. To this end, the present review aims to summarize the current progress of KOS-associated biomedical applications, especially focusing on the in vitro and in vivo effects of KOS hydrogel on cultured cells and tissue regeneration following skin injury, skeletal muscle loss, peripheral nerve injury, and cardiac infarction.

Trimethylamine N-oxide (TMAO) is a gut microbiota metabolite derived from trimethylamine- containing nutrient precursors such as choline, L-carnitine, and betaine, which are rich in many vegetables, fruits, nuts, dairy products, and meats. An increasing number of clinical studies have demonstrated a strong relationship between elevated plasma TMAO levels and adverse cardiovascular events. It is commonly agreed that TMAO acts as an independent risk factor and a prognostic index for patients with cardiovascular disease. Although most animal (mainly rodent) data support the clinical findings, the mechanisms by which TMAO modulates the cardiovascular system are still not well understood. In this context, we provide an overview of the potential mechanisms underlying TMAO-induced cardiovascular diseases at the cellular and molecular levels, with a focus on atherosclerosis. We also address the direct effects of TMAO on cardiomyocytes (a new and under-researched area) and finally propose TMAO as a potential biomarker and/or therapeutic target for diagnosis and treatment of patients with cardiovascular disease.

The detection of microRNA (miRNA) in human serum has great significance for cancer prevention. Herein, a novel self-powered biosensing platform is developed, which effectively integrates an enzymatic biofuel cell (EBFC)-based self-powered biosensor with a matching capacitor for miRNA detection. A catalytic hairpin assembly and hybrid chain reaction are used to improve the analytical performance of EBFC. Furthermore, the matching capacitor is selected as an auxiliary signal amplifying device, and graphdiyne is applied as substrate material for EBFC. The results confirm that the developed method obviously increases the output current of EBFC, and the sensitivity can reach 2.75 μA/pM, which is 786% of pure EBFC. MiRNA can be detected in an expanded linear range of 0.1-100000 fM with a detection limit of 0.034 fM (S/N = 3). It can offer a selective and sensitive platform for nucleotide sequence detection with great potential in clinical diagnostics.

Luteolin (LUT) possesses multiple biologic functions and has beneficial effects for cardiovascular and cerebral vascular diseases. Here, we investigated the protective effects of LUT against subarachnoid hemorrhage (SAH) and the involvement of underlying molecular mechanisms. In a rat model of SAH, LUT significantly inhibited SAH-induced neuroinflammation as evidenced by reduced microglia activation, decreased neutrophil infiltration, and suppressed proinflammatory cytokine release. In addition, LUT markedly ameliorated SAH-induced oxidative damage and restored the endogenous antioxidant systems. Concomitant with the suppressed oxidative stress and neuroinflammation, LUT significantly improved neurologic function and reduced neuronal cell death after SAH. Mechanistically, LUT treatment significantly enhanced the expression of nuclear factor-erythroid 2-related factor 2 (Nrf2), while it downregulated nod-like receptor pyrin domain-containing 3 (NLRP3) inflammasome activation. Inhibition of Nrf2 by ML385 dramatically abrogated LUT-induced Nrf2 activation and NLRP3 suppression and reversed the beneficial effects of LUT against SAH. In neurons and microglia coculture system, LUT also mitigated oxidative stress, inflammatory response, and neuronal degeneration. These beneficial effects were associated with activation of the Nrf2 and inhibitory effects on NLRP3 inflammasome and were reversed by ML385 treatment. Taken together, this present study reveals that LUT confers protection against SAH by inhibiting NLRP3 inflammasome signaling pathway, which may be modulated by Nrf2 activation.

Introduction Coronavirus disease-2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) swept rapidly throughout the world. So far, no therapeutics have yet proven to be effective. Ribavirin was recommended for the treatment of COVID-19 in China because of its in vitro activity. However, evidence supporting its clinical use with good efficacy is still lacking. Methods A total of 208 confirmed severe COVID-19 patients who were hospitalized in Wuhan Union West Campus between 1 February 2020 and 10 March 2020 were enrolled in the retrospective study. Patients were divided into two groups based on the use of ribavirin. The primary endpoint was the time to clinical improvement. The secondary endpoints included mortality, survival time, time to throat swab SARS-CoV-2 nucleic acid negative conversion, and the length of hospital stay. Results 68 patients were treated with ribavirin while 140 not. There were no significant between-group differences in demographic characteristics, baseline laboratory test results, treatment, and distribution of ordinal scale scores at enrollment, except for coexisting diseases especially cancer (ribavirin group vs no ribavirin group, P = 0.01). Treatment with ribavirin was not associated with a difference in the time to clinical improvement (P = 0.48, HR = 0.88, 95% CI = 0.63–1.25). There were also no significant differences between-group in SARS-CoV-2 nucleic acid negative conversion, mortality, survival time, and the length of hospital stay. Conclusions In hospitalized adult patients with severe COVID-19, no significant benefit was observed with ribavirin treatment.

Borylated aza-arenes are of great importance in the area of organic synthesis. A radical borylative cyclization of isocyanoarenes with N-heterocyclic carbene borane (NHC-BH3) under metal-free conditions was developed. The reaction allows the efficient assembly of several types of borylated aza-arenes (phenanthridines, benzothiazoles, etc.), which are difficult to access using alternative methods. Mild reaction conditions, a good functional-group tolerance, and generally good efficiencies were observed. The utility of these products is demonstrated, and the mechanism is discussed.

Herein, an original and divergent synthetic method for fluorinated 2-benzylated indoles and 2,2′-bis(indolyl)methanes has been established for the first time via Rh(III)-catalyzed C–H/C–F activation of arenes employing 3,3-difluoro-2-exo-methylidene indolines as novel cross-coupling partners. This redox-neutral protocol exhibited a broad substrate scope (30 examples, up to 97% yield) and high functional-group compatibility. Gram-scale and mechanistic studies were also performed.

A mild and selective Cp*Ir(III)- and Cp*Rh(III)-catalyzed direct C(sp2)–H amination of arenes and three types of nitrene precursor reagents is reported, with the assistance of a thioether directing group. This redox-neutral protocol proceeds under mild reaction conditions, has a broad substrate scope and high functional-group compatibility and generates the desired aminated products in moderate to excellent yields. The reaction represents the first example of a thioether-directed Cp*Ir(III)- and Cp*Rh(III)-catalyzed C(sp2)–H direct amination reaction. Moreover, azide compounds were employed as a diverse and robust aminating reagent for the first time in a thioether-directed C–H functionalization reaction.

α-Haloboronates are useful organic synthons that can be converted to a diverse array of α-substituted alkyl borons. Methods to α-haloboronates are limiting and often suffer from harsh reaction conditions. Reported herein is a photochemical radical C-H halogenation of benzyl N-methyliminodiacetyl (MIDA) boronates. Fluorination, chlorination, and bromination reactions were effective by using this protocol. Upon reaction with different nucleophiles, the C-Br bond in the brominated product could be readily transformed to a series of C-C, C-O, C-N, C-S, C-P, and C-I bonds, some of which are difficult to forge with α-halo sp2 -B boronate esters. An activation effect of B(MIDA) moiety was found.

A novel approach to prepare a HAu(Cys)2 compound via a ligand exchange reaction in an aqueous solution is introduced. The prepared HAu(Cys)2 compound is shown as a very good main salt for environme...

This study explored the influence of ferrous iron (Fe2+) addition on ammonium nitrogen (NH4-N) removal and microbial communities in horizontal subsurface flow constructed wetlands (HSSFs) at different carbon/nitrogen (C/N) ratios. Fe2+ addition could improve NH4-N removal under the C/N ratio of 2.1 and alter the microbial community structure. The microbial diversity and functional genes at the C/N ratio of 2.1 were enhanced by the addition of 50 mg/L Fe2+, with the increases observed in NH4-N and total nitrogen (TN) removal. This indicates the enhancement of nitrogen removal by Fe2+ addition with the presence of high organic matter. However, the enhancement of Fe2+ on chemical oxygen demand removal was not obvious overall. The relative abundance of functional genes and those related to energy metabolism, xenobiotic biodegradation, and metabolism decreased significantly in HSSFs with Fe2+ at C/N ratio of 1.1, whereas they increased in HSSFs with the addition of 50 mg/L Fe2+ at C/N ratio of 2.1.

Type-I clathrate compounds YbxBa8–xGa16Ge30 have been synthesized by the high-pressure and high-temperature (HPHT) method rapidly. The effects of the synergy of atom filling and pressure regulation on the microstructure and thermal and electrical properties have been investigated. With the content of Yb atom increasing, the carrier concentration is improved, the electrical resistivity and the absolute Seebeck coefficient are decreased, while the thermal conductivity is reduced significantly. A series of extremely low lattice thermal conductivities are achieved, attributed to the enhancement of multiscale phonon scattering for the “rattling” of the filled guest atoms, the heterogeneous distribution of nano- and microstructures, grain boundaries, abundant lattice distortions, lattice deformations, and dislocations. As a result, a maximum ZT of about 1.07 at 873 K has achieved for the Yb0.5Ba7.5Ga16Ge30 sample.

A hot electron bolometer (HEB) with Johnson noise readout is an attractive technique for radiation detection due to its high sensitivity, wide operating temperature range, and large dynamic range. In this paper, we present the development of a terahertz HEB based on Johnson noise readout. The HEB consists of a titanium microbridge connected to two high-energy-gap niobium contacts for confining hot electrons. We measured the thermal conductance and noise equivalent power (NEP) of the HEB at different bath temperatures. We find that the thermal conductance due to the electron–phonon interaction increases with temperature as T2.5. At 3.0 K, the thermal conductance is found to be 37.9 ± 1.4 nW/K and the electrical NEP is as low as 23.0 ± 0.8 pW/$$ \sqrt {\text{Hz}} $$. In addition, we find that the HEB works efficiently up to 15 μW input power.

BACKGROUND Ectopic fat accumulation in skeletal muscle results in dysfunction and atrophy, but the underlying molecular mechanisms remain unclear. OBJECTIVE The aim of this study was to investigate the effects of a high-fat diet (HFD) in modulating the structure and energy metabolism of skeletal muscle and the underlying mechanisms in mice. METHODS Four-week-old male C57BL/6 J mice (n = 30) were allowed 1 wk for acclimatization. After 6 mice with low body weight were removed from the study, the remaining 24 mice were fed with a normal-fat diet (NFD; 10% energy from fat, n = 12) or an HFD (60% energy from fat, n = 12) for 24 wk. At the end of the experiment, serum glucose and lipid concentrations were measured, and skeletal muscle was collected for atrophy analysis, inflammation measurements, and phosphoproteomic analysis. RESULTS Compared with the NFD, the HFD increased (P

Strain C was isolated from chicken manure, and its phenotypic characteristics were gram-stain negative, yellow-pigmented, aerobic bacterium, heterotrophic, non-motile, chemoorganotrophic, non-gliding as well as non-spore-forming. A 16S rRNA gene sequence analysis showed that strain C occupied a distinct lineage within the family of the genus Chryseobacterium, and it shared highest sequence similarity with Chryseobacterium solincola strain 1YB-R12 (80%). The new isolate has been studied for removing ammonium-nitrogen (NH4-N) and the optimization of suitable conditions. The strain C was able to degrade over 42.8% of NH4-N during its active growth cycle. Experimental study of the effect of temperature and pH on NH4-N removal showed that the temperature and pH optima for NH4-N removal were 30–35℃ and 4–8, respectively. The results indicated that strain C shows a potential application for wastewater treatment.

Global warming has been identified as a serious environmental issue. The most promising way to stop the greenhouse gas effect is to develop a high-performance membrane for CO2 separation. In this s...

Solid/liquid interfacial structure occupies great importance in chemistry, biology, and materials. In this paper, by combining EC-SERS study and DFT calculation, we reveal the adsorption and dimerization of sulfite (SO32-) at a gold electrode/water solution interface, and establish an adsorption displacement strategy to suppress the dimerization of sulfite. At the gold electrode/sodium sulfite solution interface, at least two layers of SO32- anions are adsorbed on the electrode surface. As the applied potential shifts negatively, the adsorption strength of the first SO32- layer is weakened gradually and then is dimerized with the second orientated SO32- layer to form S2O52-, and S2O52- is further reduced to S2O32-. After hydroxyethylene disphosphonic acid (HEDP) is introduced to the gold electrode/sodium sulfite solution interface, the second oriented SO32- layer is replaced by a HEDP coadsorption layer. This results in the first layer of SO32- being desorbed directly without any structural transformation or chemical reaction as the potential shifts negatively. The suppression of sulfite dimerization by HEDP is more clear at the gold electrode/gold sulfite solution interface owing to the electroreduction of gold ions. Furthermore, the electrochemical studies and electrodeposition experiments show that as the sulfite dimerization reaction is suppressed, the electroreduction of gold ions is accelerated, and the deposited gold coating is bright and dense with finer grains.

Selenoprotein V (SELENOV) is a new and the least conserved member of the selenoprotein family. Herein we generated Selenov knockout (KO) mice to determine its in vivo function. The KO led to 16–19% increases (P, Graphical abstract Image 1, Highlights • SELENOV knockout elevated body weight and fat mass accumulation in mice. • SELENOV knockout stimulated lipogenesis and inhibited lipolysis in adipose tissue. • SELENOV knockout attenuated thermogenesis, respiration, and body temperature. • SELENOV and O-GlcNAc transferase (OGT) depicted a protein-protein interaction. • SELENOV knockout lowered OGT protein, activity, and function in adipose tissue.

Liver necroptosis of chicks is induced by selenium (Se)/vitamin E (VE) deficiencies and may be associated with oxidative cell damage. To reveal the underlying mechanisms of liver necrosis, a pool of the corn–soy basal diet (10 μg Se/kg; no VE added), a basal diet plus all-rac-α-tocopheryl acetate (50 mg/kg), Se (sodium selenite at 0.3 mg/kg), or both of these nutrients were provided to day-old broiler chicks (n = 40/group) for 6 weeks. High incidences of liver necrosis (30%) of chicks were induced by –SE–VE, starting at day 16. The Se concentration in liver and glutathione peroxidase (GPX) activity were decreased (P < 0.05) by dietary Se deficiency. Meanwhile, Se deficiency elevated malondialdehyde content and decreased superoxide dismutase (SOD) activity in the liver at weeks 2 and 4. Chicks fed with the two Se-deficient diets showed lower (P < 0.05) hepatic mRNA expression of Gpx1, Gpx3, Gpx4, Selenof, Selenoh, Selenok, Selenom, Selenon, Selenoo, Selenop, Selenot, Selenou, Selenow, and Dio1 than those fed with the two Se-supplemented diets. Dietary Se deficiency had elevated (P < 0.05) the expression of SELENOP, but decreased the downregulation (P < 0.05) of GPX1, GPX4, SELENON, and SELENOW in the liver of chicks at two time points. Meanwhile, dietary Se deficiency upregulated (P < 0.05) the abundance of hepatic proteins of p38 mitogen-activated protein kinase, phospho-p38 mitogen-activated protein kinase, c-Jun N-terminal kinase, phospho-c-Jun N-terminal kinase, extracellular signal-regulated kinase, phospho-mitogen-activated protein kinase, receptor-interacting serine-threonine kinase 1 (RIPK1), receptor-interacting serine-threonine kinase 3 (RIPK3), and mixed lineage kinase domain-like (MLKL) at two time points. In conclusion, our data confirmed the differential regulation of dietary Se deficiency on several key selenoproteins, the RIPK1/RIPK3/MLKL, and mitogen-activated protein kinase signaling pathway in chicks and identified new molecular clues for understanding the etiology of nutritional liver necrosis.

Nuclear factor (NF)-κB–ty -50mediated neuroinflammation plays a crucial role in early brain injury (EBI) after subarachnoid hemorrhage (SAH). As an important negative feedback regulator of NF-κB, A20 is essential for inflammatory homeostasis. Herein, we tested the hypothesis that A20 attenuates EBI by establishing NF-κB–associated negative feedback after experimental SAH. In vivo and in vitro models of SAH were established. TPCA-1 and lentivirus were used for NF-κB inhibition and A20 silencing/overexpression, respectively. Cellular localization of A20 in the brain was determined via immunofluorescence. Western blotting and enzyme-linked immunosorbent assays were applied to observe the expression of members of the A20/tumor necrosis factor receptor-associated factor 6 (TRAF6)/NF-κB pathway and inflammatory cytokines (IL-6, IL-1β, TNF-α). Evans blue staining, TUNEL staining, Nissl staining, brain water content, and modified Garcia score were performed to evaluate the neuroprotective effect of A20. A20 expression by astrocytes, microglia, and neurons was increased at 24 h after SAH. A20 and inflammatory cytokine levels were decreased while TRAF6 expression was elevated after NF-κB inhibition. TRAF6, NF-κB, and inflammatory cytokine levels were increased after A20 silencing but suppressed with A20 overexpression. Also, Bcl-2, Bax, MMP-9, ZO-1 protein levels; Evans blue, TUNEL, and Nissl staining; brain water content; and modified Garcia score showed that A20 exerted a neuroprotective effect after SAH. A20 expression was regulated by NF-κB. In turn, increased A20 expression inhibited TRAF6 and NF-κB to reduce the subsequent inflammatory response. Our data also suggest that negative feedback regulation mechanism of the A20/TRAF6/NF-κB pathway and the neuroprotective role of A20 to attenuate EBI after SAH.

Metabolic syndrome (MetS) is a set of complex, chronic inflammatory conditions that are characterized by central obesity and associated with an increased risk of cardiovascular diseases. In recent years, microRNAs (miRNAs) have become an important type of endocrine factors, which play crucial roles in maintaining energy balance and metabolic homeostasis. However, its unfavorable properties such as easy degradation in blood and off-target effect are still a barrier for clinical application. Nanosystem based delivery possess strong protection, high bioavailability and control release rate, which is beneficial for success of gene therapy. This review first describes the current progress and advances on miRNAs associated with MetS, then provides a summary of the therapeutic potential and targets of miRNAs in metabolic organs. Next, it discusses recent advances in the functionalized development of classic delivery systems (exosomes, liposomes and polymers), including their structures, properties, functions and applications. Furthermore, this work briefly discusses the intelligent strategies used in emerging novel delivery systems (selenium nanoparticles, DNA origami, microneedles and magnetosomes). Finally, challenges and future directions in this field are discussed provide a comprehensive overview of the future development of targeted miRNAs delivery for MetS treatment. With these contributions, it is expected to address and accelerate the development of effective NA delivery systems for the treatment of MetS.

Fifteen chalcone derivatives 3a-3o were synthesized, and evaluated as multifunctional agents against Alzheimer's disease. In vitro studies revealed that these compounds inhibited self-induced Aβ1-42 aggregation effectively ranged from 45.9-94.5 % at 20 μM, and acted as potential antioxidants. Their structure-activity relationships were summarized. In particular, (2E)-3-[4-(dimethylamino)phenyl]-1-(pyridin-2-yl)prop-2-en-1-one (3g) exhibited an excellent inhibitory activity of 94.5 % at 20 μM, and it could disassemble the self-induced Aβ1-42 aggregation fibrils with ratio of 57.1 % at 20 μM concentration. In addition, compound 3g displayed good chelating ability for Cu2+ , and could effectively inhibit and disaggregate Cu2+ -induced Aβ aggregation. Moreover, compound 3g exerted low cytotoxicity, significantly reversed Aβ1-42 -induced SH-SY5Y cell damage. More importantly, compound 3g remarkably ameliorated scopolamine-induced memory impairment in mice. In summary, all the results revealed compound 3g was a potential multifunctional agent for AD therapy.

Selenium (Se) is an essential element for the maintenance of a healthy physiological state. However, due to environmental and dietary factors and the narrow safety range of Se, diseases caused by Se deficiency or excess have gained considerable traction in recent years. In particular, links have been identified between low Se status, cognitive decline, immune disorders, and increased mortality, whereas excess Se increases metabolic risk. Considerable evidence has suggested microRNAs (miRNAs) regulate interactions between the environment (including the diet) and genes, and play important roles in several diseases, including cancer. MiRNAs target messenger RNAs to induce changes in proteins including selenoprotein expression, ultimately generating disease. While a plethora of data exists on the epigenetic regulation of other dietary factors, nutrient Se epigenetics and especially miRNA regulated mechanisms remain unclear. Thus, this review mainly focuses on Se metabolism, pathogenic mechanisms, and miRNAs as key regulatory factors in Se-related diseases. Finally, we attempt to clarify the regulatory mechanisms underpinning Se, miRNAs, selenoproteins, and Se-related diseases.

Lung cancer is the most commonly diagnosed cancer with a high mortality rate. Cisplatin is one of the most important chemotherapeutic agents for the treatment of lung cancer patients, especially in advanced stages. Recent studies showed that cisplatin may interact with mitochondria which may partly account for its cytotoxicity. In the study, we explored the effect of resistin on cisplatin-induced cytotoxicity in A549 cells and assessed whether mitochondria-dependent apoptosis was involved. Our results found that 25 ng/ml resistin could significantly increase cisplatin-induced apoptosis and G2/M phase arrest, enhance reactive oxygen species generation, exacerbate the collapse of mitochondrial membrane potential, promote the distribution of cytochrome C in the cytoplasm from mitochondria, and activate caspase 3. Therefore, the results suggested that resistin might increase cisplatin-induced cytotoxicity via a mitochondria-mediated pathway in A549 cells. However, the precise mechanism has yet to be explored in the future.

Chronic myelogenous leukemia (CML) typically results from a reciprocal translocation between chromosomes 9 and 22 to produce the bcr-abl oncogene that when translated, yields the p210 BCR-ABL protein in more than 90% of all CML patients. This protein has constitutive tyrosine kinase activity that activates numerous downstream pathways that ultimately produces uncontrolled myeloid proliferation. Although the use of the BCR-ABL tyrosine kinase inhibitors (TKIs), such as imatinib, nilotinib, dasatinib, bosutinib, and ponatinib have increased the overall survival of CML patients, their use is limited by drug resistance and severe adverse effects. Therefore, there is the need to develop novel compounds that can overcome these problems that limit the use of these drugs. Therefore, in this study, we sought to find novel compounds using Hypogen and Hiphip pharmacophore models based on the structures of clinically approved BCR-ABL TKIs. We also used optimal pharmacophore models such as three-dimensional queries to screen the ZINC database to search for potential BCR-ABL inhibitors. The hit compounds were further screened using Lipinski’s rule of five, ADMET and molecular docking, and the efficacy of the hit compounds was evaluated. Our in vitro results indicated that compound ZINC21710815 significantly inhibited the proliferation of K562, BaF3/WT, and BaF3/T315I leukemia cells by inducing cell cycle arrest. The compound ZINC21710815 decreased the expression of p-BCR-ABL, STAT5, and Crkl and produced apoptosis and autophagy. Our results suggest that ZINC21710815 may be a potential BCR-ABL inhibitor that should undergo in vivo evaluation.

Lanthanide coordination polymers (Ln-CPs) {[Ln(HL)2(H2O)3]·(H2O)4·Cl}n (Ln = Dy, 1; Eu, 2; Sm, 3) and [Ln0.18(HL)0.18(CH3COO)0.36(H2O)0.54]n (Ln = La, 4; H2L = 2-(hydroxymethyl)-1H-benzo[d]imidazole-5-carboxylic acid) have been successfully assembled by Ln3+ ions and asymmetric carboxylic acid ligand under solvothermal conditions. The structures of the complexes 1–4 were determined by single crystal X-ray diffraction and further characterized by elemental analyses, IR spectroscopy, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA). The structure analysis display that complexes 1–3 are isostructural three-dimensional (3D) supramolecular network. Complexes 1–4 were constructed by hydrogen bonding interactions between the coordinated water molecules and the O atoms of the hydroxy group or free chloride ions. Furthermore, luminescence properties of complexes 1–4 have been measured in the solid state at room temperature. Complex 2 exhibits a strong red luminescence upon excitation at 283 nm and its lifetimes is 33.554 ns. In addition, magnetic studies reveal that complex 1 has a weak antiferromagnetic interaction.

The flexible synthesis of tetra- and triarylethenes bearing different aryl groups has been a long-standing challenge in organic synthesis. Here we report a palladium-catalysed syn-diarylation of arylethynyl N-methyliminodiacetyl (MIDA) boronates. The products, triarylalkenyl N-methyliminodiacetyl boronates, allow a step-economic and modular synthesis of tetra- or triarylethenes via a subsequent stereospecific Suzuki-Miyaura coupling reaction or base-promoted protodeborylation, respectively. Use of the sp3-B(MIDA) masked aryl alkyne is the key factor for success by offering an exceptionally good regioselectivity for the boron-retentive coupling. The unusual regioselectivity is believed to arise from the stabilization due to the strong electron donation from the C−Pd σ bond to the p-orbital of boron in the transition state of migratory insertion. A broad range of differently substituted tetra- and triarylethenes are constructed in good yields and geometrical control. Synthetic manipulation of the C-B bond also enables the facile construction of several other types of tetra-substituted alkenes. The synthesis of tri- and tetra-aryl alkenes is limited by poor regio- and stereoselectivity. Here MIDA boronate-substituted aryl alkynes are used to achieve regioselective three-component diarylation of the alkyne and to provide a cross-coupling handle for subsequent elaboration to tri- or tetra-substituted products.

Six new coordination polymers(CPs) {[Cd(L1)(CHDA)]·H2O}n (1), [Zn3(L1)2(1,2,4-BTC)2(H2O)4]n (2), [Zn(L2)(D-CAM)(H2O)]n (3), [Zn3(L2)(1,2,4-BTC)2(H2O)4]n (4), [Cd(L2)(1,3,5-HBTC)]n (5) and {[Zn(L2)(4,4´-BOA)]·H2O}n (6) (L1 = 3,6-bis(imidazol-1-yl)pyridazine, L2 = 3,6-bis(benzimidazol-1-yl)pyridazine, 1,4-H2CHDA = (1 S,4 S)-cyclohexane-1,4-dicarboxylic acid, 1,2,4-H3BTC = benzene-1,2,4-tricarboxylic acid, D-CAM = (1 R,3 S)-1,2,2-trimethylcyclopentane-1,3-dicarboxylic acid, 1,3,5-H3BTC = benzene-1,3,5-tricarboxylic acid, 4,4´-H2OBA = 4,4´-oxydibenzoic acid) were achieved by reactions of the corresponding metal salt with mixed organic ligands. Their structures were determined by single-crystal X-ray diffraction, IR spectra, elemental analysis, powder X-ray diffraction and thermogravimetric analysis. They exhibit varied structures, complexes 4 and 5 are porous three-dimensional (3D) frameworks, while 2 and 3 are 3D supermolecule structure formed by hydrogen-bonding interactions, and 1 is a two-dimensional (2D) network and 6 is an infinite one-dimensional (1D) chain. In addition, the fluorescent emission, fluorescence lifetimes of L1, L2 and 1–6 have been investigated and discussed.

Three new coordination polymers [Co(L)(1,2,4,5-BTC)0.5(H2O)]n (1), {[Ni(L)(1,2-BDC)(H2O)3]·H2O}n (2) and {[Zn3(L)2(1,3,5-BTC)2(H2O)2]·3H2O}n (3) [L = 3,6-bis(imidazole-1-yl)pyridazine, H4BTC = 1,2,4,5-Benzenetetracarboxylic acid, H2BDC = 1,2-Benzenedicarboxylic acid, H3BTC = 1,3,5-Benzenetricarboxylic acid] were synthesized based on a rigid ligand L and different aromatic carboxylic acid ligands under solvothermal conditions. The structures of the complexes 1–3 were determined by single crystal X-ray diffraction and further characterized by elemental analyses, IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). In addition, UV–vis diffuse-reflectance spectra demonstrate wide band gaps. The structural analysis reveals that complex 1 features a two-dimensional (2D) layer structure with a 6-connected sql topological net. Complex 2 shows a one-dimensional (1D) zigzag chain, while complex 3 displays a three-dimensional (3D) coordination network which exhibits an intriguing (5,5,6)-connected novel topological net with the point symbol of {32·42·53·63}2{32·44·54·63·72}. Moreover, the luminescence property and lifetimes of complex 3 has been measured at room temperature. Furthermore, in the complex-catalyzed homocoupling reaction of 4-substituted aryl iodides, the catalytic activities of complexes 1–3 have also been studied and discussed.

A hydrothermal procedure has been developed to produce azine-linked COFs by conducting condensation reactions of hydrazine with hydroxy-substituted 1,3,5-triformylbenzene in water. The synthesis of one representative COF was drastically promoted by water in comparison with the traditional solvothermal reactions in organic solvents. This synthesis has advantages of large-scale production, catalyst-free reaction, short reaction time, and the obtained COF exhibits higher crystallinity and surface area.

Benzofused nitrogen heterocycles are prevalent as key core structural motifs in functional molecules. Major syntheses of benzofused nitrogen heterocycles focus on construction of the heterocyclic ring starting from (poly)substituted benzene derivatives. Given that polysubstituted benzene derivatives are not always easily available, the flexibility of these methods may be problematic. The direct benzannulation reactions of simple N-heterocycles thus provide a complementary and valuable strategy. However, this approach has been far less explored, especially when nonprefunctionalized N-heterocycles are used as starting materials. In recent years, the metal-catalyzed direct functionalization of an inert C–H bond has become a powerful tool to construct (hetero)aromatics. In the C–H benzannulation reactions, alkynes, activated alkenes, enaldiazo compounds, and biaryl compounds were previously utilized as efficient coupling partners. Reported herein is a de novo synthesis of a benzene ring through the rhodium-ca...

Glutathione peroxidase 1 (GPX1) is a selenium-dependent enzyme that reduces intracellular hydrogen peroxide and lipid peroxides. While past research explored regulations of gene expression and biochemical function of this selenoperoxidase, GPX1 has recently been implicated in the onset and development of chronic diseases. Clinical data have shown associations of human GPX1 gene variants with elevated risks of diabetes. Knockout and overexpression of Gpx1 in mice may induce types 1 and 2 diabetes-like phenotypes, respectively. This review assembles the latest advances in this new field of selenium biology, and attempts to postulate signal and molecular mechanisms mediating the role of GPX1 in glucose and lipid metabolism-related diseases. Potential therapies by harnessing the beneficial effects of this ubiquitous redox-modulating enzyme are briefly discussed.

For the first time, we present an original sensing strategy with an ultra-wide detection window from 17 nM to 20 mM to detect SCN- ions. Initially, we investigated the clustering and optical properties of noble metal sol nanoparticles (NPs) due to the competitive interaction of thiocyanate ions (SCN-) and cetyltrimethylammonium bromide (CTAB) under weak acidic conditions, and found that different dimensions and scales of nanoclusters containing the alkyne-embedded Au@Ag NPs and relatively small Ag NPs could be achieved by the mediation of CTAB through electrostatic forces and hydrophobic interaction, in which SCN- could be covalently bonded with the silver surface of NPs to form a compact molecular layer (-Ag-S-C[triple bond, length as m-dash]N), and CTAB could only occupy remaining sites. In this process, we found that SCN- always runs counter to CTAB and tends to dissolve nanoclusters, so that they occupy the exposed surface of NPs in nanoclusters rather than the binding sites of one another. Remarkably, when the concentration of SCN- initially increased, two highly recognizable SERS emissions, which were assigned to alkyne reporter molecules (2208 cm-1) and C[triple bond, length as m-dash]N of SCN- (2110 cm-1), respectively, were rapidly detected, and their ratios (I2110/I2208) increased linearly proportional to the concentration of SCN- over a range of 17 nM to 172 μM, with a limit of detection (LOD) of 10 nM. With the further increase of SCN-, small Ag NPs started to desorb from the surface of individual Au@Ag NPs and dissociated in the solution but did not contribute to SERS signals. Instead, the surface plasmon resonance (SPR) peak of pure silver NPs at 385 nm increased gradually in the range from 0.5 to 20 mM with an LOD of 0.2 mM. Of particular significance, this simple sensor in conjunction with surface-enhanced Raman-extinction spectroscopy can be used for the rapid detection of extensive samples with an ultra-wide detection window, such as body fluids (saliva, urine, and serum) and food (milk powder and brassica vegetables), which is far superior to that of ion chromatography (IC).

BACKGROUND Lactoferrin (LF) has been shown to promote bone anabolism, and the vitamin D receptor (VDR) mediates the effects of vitamin D on bone. We hypothesized that LF improves bone health by increasing VDR expression. OBJECTIVES We sought to determine the role of VDR activation in LF-induced osteogenic activity in vivo and in vitro and the underlying molecular mechanisms. METHODS Sixty male C57BL/6J mice (aged 4 wk) were randomly assigned into 6 groups and fed vitamin D-deficient (VDD; 0 IU/kg) or vitamin D-normal diet (VDN; 1000 IU cholecalciferol/kg) and administered placebo or LF (100 or 1000 mg/kg body weight) by gavage for 24 wk. Trabecular bone structure was analyzed using micro-CT, and VDR expression was assessed by immunohistochemistry. In vitro, MC3T3-E1 cells were treated with 100 μg LF/mL to evaluate its effect on VDR expression. Finally, the direct recruitment of LF to the Vdr promoter was confirmed by chromatin immunoprecipitation assay. In addition, cells were transfected with pGL3-basic Vdr vector for monitoring Vdr promoter activation using luciferase assays. RESULTS LF supplementation at 100 and 1000 mg/kg revealed an ∼6.5% (P

Transition edge sensors (TES) are highly sensitive detectors and have been widely used at different wavelengths from millimeter to X-ray astronomy. Especially at optical/near infrared wavelengths TES exhibits photon-number resolving capability because of its high energy resolution, which also makes it attractive in quantum information. In order to verify the possibility of space applications, we study the effect of ion irradiation on the performance of titanium-based optical TESs including normal-state resistance (RN), critical temperature (TC), thermal conductance (G), effective response time, detection efficiency, and energy resolution by measuring the DC and optical characteristics. The optical TESs survive in the ion irradiation and their parameters keep almost the same as before ion irradiation, which makes it possible for future space applications.

Background: Coronavirus disease-2019 (COVID-19) spreads rapidly throughout the world. So far, no therapeutics have yet been proven to be effective. Ribavirin was recommended for the treatment of COVID-19 because of its in vitro activity. However, evidence supporting its clinical use with good efficacy is still lacking.Methods: A total of 208 confirmed severe or critical COVID-19 patients who were hospitalized in Wuhan Union West Campus between 1 February 2020 and 10 March 2020 were enrolled in the retrospective study. Patients were divided into two groups based on the use of ribavirin. The primary endpoint was the time to clinical improvement. The secondary endpoints included mortality, survival time, time to throat swab SARS-CoV-2 nucleic acid negative conversion, and hospital duration.Results: 68 patients were treated with ribavirin while 140 not. There were no significant between-group differences in demographic characteristics, baseline laboratory test results, treatment, and distribution of ordinal scale scores at enrollment, except coexisting diseases especially cancer (ribavirin group vs no ribavirin group, P = 0.014). Treatment with ribavirin was not associated with a difference in the time to clinical improvement (P = 0.483, HR = 0.884, 95% CI = 0.627-1.247). There were also no significant differences between-group in the number of patients with SARS-CoV-2 nucleic acid negative conversion, mortality, survival time, and hospital duration. Conclusion: In hospitalized adult patients with severe or critical COVID-19, no significant benefit was observed with ribavirin treatment.

Selenoprotein V (SELENOV) contains a thioredoxin-like fold and a conserved CxxU motif with a potential redox function. This study was to assess its in vivo and in vitro roles and mechanisms in coping with different oxidant insults. In Experiment (Expt.)1, SELENOV knockout (KO) and wild type (WT) mice (male, 8-wk old) were given an ip injection of saline, diquat (DQ, 12.5 mg/kg), or N-acetyl-para-aminophenol (APAP, 300 mg/kg) (n = 10), and killed 5 h after the injection. In Expt. 2, primary hepatocytes of WT and KO were treated with DQ (0–0.75 mM) or APAP (0–6 mM) for 12 h. In Expt. 3, 293 T cells overexpressing Selenov gene (OE) were treated with APAP (0–4 mM) for 24 h or H2O2 (0–0.4 mM) for 12 h. Compared with the WT, the DQ- and APAP-injected KO mice had higher (P

OBJECTIVES: Selenoprotein V (SELENOV) contains a thioredoxin-like fold and a conserved CxxU motif with a potential redox function. Three experiments were performed to assess its in vivo and in vitro roles and mechanisms in coping with different oxidant insults. METHODS: In Expt.1, SELENOV knockout (KO) and wildtype (WT) mice (male, 8-wk old) were given an IP injection of saline, diquat (DQ, 12.5 mg/kg), or acetaminophen (APAP, 300 mg/kg) (n = 10), and killed 5 h after the injection to collect liver and blood. In Expt. 2, primary hepatocytes were isolated from the 2 genotypes, cultured in complete Williams's medium E, and treated with DQ (0, 0.25 and 0.75 mM) and APAP (0, 1, 3, and 6 mM) for 12 h. In Expt. 3, 293 T cells were transfected with a control plasmid (GFP) or the plasmid containing Selenov gene (full length, OE) and treated with APAP (0, 1, 2, and 4 mM) for 24 h or H(2)O(2) (0.1, 0.2, and 0.4 mM) for 12 h. RESULTS: In Expt. 1, the DQ and APAP injections caused greater (P

A novel lactate dehydrogenase gene, named lrldh, was cloned from Lactobacillus rossiae and heterologously expressed in Escherichia coli. The lactate dehydrogenase LrLDH is NADH-dependent with a molecular weight of approximately 39 kDa. It is active at 40 °C and pH 6.5 and stable in a neutral to alkaline environment below 35 °C. The kinetic constants, including maximal reaction rate (Vmax), apparent Michaelis–Menten constant (Km), turnover number (Kcat) and catalytic efficiency (Kcat/Km) for phenylpyruvic acid were 1.95 U mg−1, 2.83 mM, 12.29 s−1, and 4.34 mM−1 s−1, respectively. Using whole cells of recombinant E. coli/pET28a-lrldh, without coexpression of a cofactor regeneration system, 20.5 g l−1 d-phenyllactic acid with ee above 99% was produced from phenylpyruvic acid in a fed-batch biotransformation process, with a productivity of 49.2 g l−1 d−1. Moreover, LrLDH has broad substrate specificity to a range of ketones, keto acids and ketonic esters. Taken together, LrLDH is a promising biocatalyst for the efficient synthesis of d-phenyllactic acid and other fine chemicals.