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Osteoporosis is one of the most common metabolic bone diseases affecting millions of people. We previously found that harmine prevents bone loss in ovariectomized mice via increasing preosteoclast platelet‐derived growth factor‐BB (PDGF‐BB) production and type H vessel formation. However, the molecular mechanisms by which harmine promotes preosteoclast PDGF‐BB generation are still unclear. In this study, we revealed that inhibitor of DNA binding‐2 (Id2) and activator protein‐1 (AP‐1) were important factors implicated in harmine‐enhanced preosteoclast PDGF‐BB production. Exposure of RANKL‐induced Primary bone marrow macrophages (BMMs), isolated from tibiae and femora of mice, to harmine increased the protein levels of Id2 and AP‐1. Knockdown of Id2 by Id2‐siRNA reduced the number of preosteoclasts as well as secretion of PDGF‐BB in RANKL‐stimulated BMMs administrated with harmine. Inhibition of c‐Fos or c‐Jun (components of AP‐1) both reversed the stimulatory effect of harmine on preosteoclast PDGF‐BB production. Dual‐luciferase reporter assay analyses determined that PDGF‐BB was the direct target of AP‐1 which was up‐regulated by harmine treatment. In conclusion, our data demonstrated a novel mechanism involving in the production of PDGF‐BB increased by harmine, which may provide potential therapeutic targets for bone loss diseases.

Both afterglow-catalysis and photoluminescence (PL) self-reporting of pollutant degradation are achieved by persistent luminescent ethylenediaminetetraacetic acid disodium (EDTA)-etched Cr3+-doped ...

Background To determine the safety and efficacy of different doses of tolvaptan for treating Chinese cirrhotic patients with or without hyponatraemia who still had ascites after routine therapy with diuretics. Methods In the present placebo-controlled, randomized, double-blinded, multicentre clinical trial, patients with cirrhotic ascites who failed to adequately respond to a combination of an aldosterone antagonist plus an orally administered loop diuretic were randomly placed at a 4:2:1 ratio into 3 groups [the 15 mg/day tolvaptan group (N = 301), 7.5 mg/day tolvaptan group (N = 153) and placebo group (N = 76)] for 7 days of treatment. The effects and safety were evaluated on days 4 and 7. A change in body weight from baseline on day 7 of treatment was the primary endpoint. Results The administration of 7.5 or 15 mg/day tolvaptan significantly decreased body weight from baseline on day 7 of treatment compared to that with placebo treatment (P = 0.026; P = 0.001). For the secondary endpoints, changes in abdominal circumference from baseline and improvements in ascites were markedly different in the treatment groups and the placebo group on day 7 (P7.5 = 0.05, P15.0 = 0.002 and P7.5 = 0.037, P15.0 = 0.003), but there was no difference between the 7.5 mg/day and 15 mg/day dosage groups. The 24-h cumulative urine volume was higher in the 7.5 mg/day and 15 mg/day tolvaptan groups than the placebo group (P = 0.002, P P = 0.004). Sodium serum concentrations were higher in patients with hyponatraemia after tolvaptan treatment, with no significant difference between the two dosage groups. The incidence of serious adverse drug reactions was not different between the groups (P = 0.543). Conclusions Tolvaptan treatment at 7.5 mg per day might be a good therapeutic choice for Chinese cirrhotic patients with ascites who did not achieve satisfactory clinical responses to previous treatment regimens with combination therapy with an aldosterone antagonist and an orally administered loop diuretic. Trial registration NCT01349348. Retrospectively registered May 2011.

We will study the spin-polarized transport through devices of single-ion magnets. A device consisted of the scanning tunneling microscopy (STM) Co tip, the single-ion magnet (Cp*) Ln (COT) (Cp* represents pentamethyl pentacadiene; Ln represents ErIII, DyIII, HoIII; COT stands for cyclooctatetraene), and the Au(111) substrate is proposed. We calculate the current curve for the parallel and anti-parallel configurations for the device of Er single-ion magnet, and find that the tunnel magnetoresistance (TMR) changes with bias − 34~24%, which indicates it is promising for the application in magnetic storage. After comparing the currents through devices of (Cp*) Ln (COT) single-ion magnets, we find that Er single-ion magnet has a better rectifying character than Dy and Ho single-ion magnet, but Ho single-ion magnet has an obvious negative differential conductance. By analysis of their transmission spectrums, these properties are well explained. The spin-polarized transport for the derivatives of Er single-ion magnets is also investigated; we find that they have better rectification and negative differential conductance features, and have potential application on multifunctional molecular devices.

Background::Atrial natriuretic peptide (ANP) and its natriuretic peptide receptors A (NPR-A) and C (NPR-C) are involved in the regulation of physiological and pathophysiological process of blood pressure. The present study aimed to determine the role of NPR-C in the development of salt-sensitive hypertension.Methods::The Dahl salt-sensitive (DS) and salt-resistant (DR) rats were used in this study. Animals were matched according to their age and weight, and then placed on either a high-salt (HS, 8%) or a normal-salt (NS, 0.4%) diet for 6 weeks randomly using random number table. The systolic blood pressure (SBP), plasmatic sodium concentration (PL Na), urinary sodium excretion (UV Na), and serum creatinine concentration (Scr) were measured. The concentration of ANP in blood and tissues (heart and kidney) was detected by enzyme-linked immunosorbent assay. The expression of ANP, NPR-A, and NPR-C in kidney was evaluated with western blot analysis. Regarding renal redox state, the concentration changes in malondialdehyde (MDA), lipofuscin, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox), and nitric oxide synthase (NOS) in kidney were detected by a spectrophotometric method. The kidney damage was evaluated using pathological techniques and the succinodehydrogenase (SDHase) examination. Furthermore, after an intra-peritoneal injection of C-atrial natriuretic peptide (ANP) 4-23 (C-ANP 4-23), an NPR-C receptor agonist, the SBP, biochemical values in blood and urine, and renal redox state were evaluated. The paired Student’s t test and analysis of variance followed by the Bonferroni test were performed for statistical analyses of the comparisons between two groups and multiple groups, respectively. Results::The baseline SBP in all groups was within the normal range. At the end of the 6-week experiment, HS diet significantly increased the SBP in DS rats from 116.63 ± 2.90 mmHg to 162.25 ± 2.15 mmHg ( t = -10.213, P < 0.001). The changes of SBP were not significant in DS rats on an NS diet and DR rats on an NS diet or on an HS diet (all P > 0.05). The significant increase of PL Na, UV Na, and Scr related to an HS diet was found in both DS and DR rats (all P < 0.05). However, significant changes in the concentration ( t= -21.915, P < 0.001) and expression of renal ANP ( t= -3.566, P = 0.016) and the expression of renal NPR-C ( t = 5.864, P = 0.002) were only observed in DS hypertensive rats. The significantly higher desmin immunochemical staining score ( t = -5.715, P = 0.005) and mitochondrial injury score ( t = -6.325, P = 0.003) accompanied by the lower SDHase concentration ( t= 3.972, P = 0.017) revealed mitochondrial pathologic abnormalities in podocytes in DS rats with an HS diet. The distinct increases of MDA ( t= -4.685, P= 0.009), lipofuscin ( t= -8.195, P= 0.001), and Nox ( t= -12.733, P < 0.001) but not NOS ( t = -0.328, P = 0.764) in kidneys were also found in DS hypertensive rats. C-ANP 4-23 treatment significantly decreased the SBP induced by HS in DS rats ( P < 0.05), which was still higher than NS groups with the vehicle or C-ANP 4-23 treatment ( P < 0.05). Moreover, the HS-induced increase of MDA, lipofuscin, Nox concentrations, and Nox4 expression in DS rats was significantly attenuated by C-ANP 4-23 treatment as compared with those with HS diet and vehicle injection (all P < 0.05). Conclusions::The results indicated that the renal NPR-C might be involved in the salt-sensitive hypertension through the damage of mitochondria in podocytes and the reduction of the anti-oxidative function. Hence, C-ANP 4-23 might serve as a therapeutic agent in treating salt-sensitive hypertension.

Background: The diagnosis of contrast-induced nephropathy (CIN) is usually based on changes in serum creatinine (sCr). However, sCr has poor sensitivity as a biomarker of kidney injury. The aim of this study was to investigate the usefulness of serum cystatin C (sCysC) to predict CIN after intra-arterial interventions. Methods: A total of 360 consecutive patients underwent intra-arterial procedures using digital subtraction angiography. SCr, sCysC, and estimated glomerular filtration rate were measured at 1 to 2 days before and at 48, 72 h, and 7 days after the procedure. Results: Thirty-one patients (8.61%) developed CIN. Receiver operating characteristic (ROC) curve analysis showed that preoperative sCysC levels had good discriminatory power (area under the curve [AUC] = 0.634; 95% confidence interval [CI] = 0.526-0.743) for evaluating the risk of CIN after an endovascular procedure, with a sensitivity of 53.33% and specificity of 73.70%. ROC analysis showed that sCysC at 48 h after contrast medium administration was predictive of CIN after an endovascular procedure (AUC = 0.735; 95% CI = 0.647-0.822) with satisfactory sensitivity of 74.20% and specificity of 63.90%. Diabetes mellitus was an independent risk factor for CIN (odds ratio = 2.778; 95% CI = 1.045-7.382; P = 0.040). Conclusions: SCysC is an appropriate biomarker to predict the occurrence of CIN. Baseline sCysC before an intervention is useful to obtain a preliminary estimate of the risk of CIN. A 48-h cut-off value of sCysC of 0.99 mg/L after an endovascular procedure may help to rule out patients at lower risk of CIN. Key words: Contrast-induced nephropathy; Intra-arterial intervention; Serum cystatin C; Serum creatinine

An efficient synthesis of a variety of 2,5-diaryloxazole derivatives via a rhodium-catalyzed annulation of triazoles and aldehydes is achieved. Various oxazole derivatives could be obtained in good to excellent yields. A concise synthesis of antimycobaterial natural products balsoxin and texamine has been achieved using this method.

Flexible color adaptation to available ecological niches is vital for the photosynthetic organisms to thrive. Hence, most purple bacteria living in the shade of green plants and algae apply bacteriochlorophyll a pigments to harvest near infra-red light around 850–875 nm. Exceptions are some Ca2+-containing species fit to utilize much redder quanta. The physical basis of such anomalous absorbance shift equivalent to ~5.5 kT at ambient temperature remains unsettled so far. Here, by applying several sophisticated spectroscopic techniques, we show that the Ca2+ ions bound to the structure of LH1 core light-harvesting pigment–protein complex significantly increase the couplings between the bacteriochlorophyll pigments. We thus establish the Ca-facilitated enhancement of exciton couplings as the main mechanism of the record spectral red-shift. The changes in specific interactions such as pigment–protein hydrogen bonding, although present, turned out to be secondary in this regard. Apart from solving the two-decade-old conundrum, these results complement the list of physical principles applicable for efficient spectral tuning of photo-sensitive molecular nano-systems, native or synthetic.

Rotifer Brachionus rotundiformis is the first live food for larval fish that can generally be plagued by ammonia (AC) in intensive culture systems. Ammonia accumulates enough to cause rotifer death. L-carnitine (LC) as a supplement of a vitamin-like nutrient can ameliorate rotifer growth performance and reproduction. The present study investigated the effects of LC on growth performance, antioxidant enzymatic activity, bacterial numbers and eradication of AC toxicity in rotifer. During a 7-day culture experiment added different concentration LC, Acute toxicity tests of AC and a batch culture experiment treated with LC and AC were performed. The results indicated that suitable LC concentration (1−100 mgL−1) treatment promoted significantly the rotifer population growth, while the AC was opposite and the AC median lethal concentration (LC50)-24 h was 12.24 mg L-1. Batch culture results showed that, under AC stress, LC significantly increased the rotifer population density and egg rate, and reduced rotifer malondialdehyde (MDA) level, increased rotifer Superoxide dismutase (SOD), Catalase (CAT), glutathione peroxidase (GPx) and total antioxidant capacity (T-AOC) activities. For the bacterial numbers, all treatments presented an increasing trend during the culture period, and there was a significant correlation with the rotifer population density especially in the group LC + AC. Overall, our results indicate that the rotifer growth can be inhibited by the AC, and under AC stress, LC can also improve the population growth, anti-stress ability of rotifer and the bacterial numbers in the medium. The amelioration of rotifer-growth may be linked to the anti-stress ability and the bacterial numbers.

The long-term patency rate of saphenous vein (SV) grafts is poor compared to arterial grafts. To investigate the effects of surgical preparation (distention) of SV on hydrogen sulfide (H2S) released from the endothelium, human SV segments were harvested from 43 patients during coronary artery bypass surgery (CABG). Acetylcholine (ACh) induced relaxation that was inhibited by NG-nitro-L-arginine + indomethacin and cysteine aminotransferase inhibitor aminooxyacetic acid in the normal SV. In contrast, ACh did not evoke relaxation in the distended SV (DSV). The concentration of H2S quantified by methylene blue assay in DSV was significantly lower than that in control. Transmission electron microscope and immunohistochemistry studies showed that the preparation destroyed the endothelium, smooth muscle, organelle, and vasa vasorum. We conclude that surgical preparation injures the endothelium and smooth muscle of the SV grafts and reduces H2S release from SV. These effects may contribute to the poor long-term patency of the SV graft.

Graphene or graphene oxide reinforced chitosan composites were widely demonstrated to exhibits potential applications in bone tissue engineering for their excellent biocompatibility and osteoinductivity. Nevertheless, the poor mechanical properties that caused by the weak interfacial interactions between graphene or graphene oxide and chitosan limit their applications to a great extent. In the study, graphene oxide reinforced chitosan with chemical interfacial bonding ( CN bond) through the amide reaction significantly improved the interfacial interactions and then the mechanical properties of the composites. The compression testing demonstrated effects of the interfacial modification on the mechanical properties of composites. X-ray photoelectron spectroscopy (XPS) results indicated that the new formation of C N bond between graphene oxide and the chitosan matrix. ReaxFF molecular dynamics simulations were carried out to investigate the interactions between graphene oxide and chitosan at the atomistic scale. In vitro cytocompatibility testing demonstrated that the interfacial chemical modifications exhibit no effects on the biocompatibility of the composites. Thus, a meaningful way was proposed in this study to obtain the graphene oxide/chitosan biocomposites for tissue engineering with improved mechanical properties and excellent biocompatibility.

The synthesis of a new azobenzene (azo)-containing main-chain crystalline polymer with reactive secondary amino groups in its backbone and photodeformation behaviors of its supramolecular hydrogen-bonded fibers are described. This main-chain azo polymer (namely Azo-MP6) was prepared via first the synthesis of a diacrylate-type azo monomer and its subsequent Michael addition copolymerization with trans-1,4-cyclohexanediamine under a mild reaction condition. Azo-MP6 was found to have a linear main-chain chemical structure instead of a branched one, as verified by comparing its 1H-NMR spectrum with that of the azo polymer prepared via the polymer analogous reaction of Azo-MP6 with acetic anhydride. The thermal stability, phase transition behavior, and photoresponsivity of Azo-MP6 were characterized with TGA, DSC, POM, XRD, and UV-Vis spectroscopy. The experimental results revealed that it had good thermal stability, low glass transition temperature, broad crystalline phase temperature range, and highly reversible photoresponsivity. Physically crosslinked supramolecular hydrogen-bonded fibers with good mechanical properties and a high alignment order of azo mesogens were readily fabricated from Azo-MP6 by using the simple melt spinning method, and they could show " reversible” photoinduced bending under the same UV light irradiation and good anti-fatigue properties.

Silicalite-1-type zeolites with unique intracrystal holes or cracks were successfully prepared using a cellulose nanofiber (CNF) as an additional mediating material, and their vapor phase adsorption properties toward methyl tert-butyl ether (MTBE) and n-nitrosodimethylamine (NDMA) were examined. It was found that the mixing protocol of CNF and structure-directing agents (SDAs), the addition amount of CNF, and the CNF/SDAs amount ratio play important roles in forming the holed silicalite-1. The synthesis route that preliminarily mixes CNF with SDAs in a series of controlled conditions is particularly beneficial for the formation of the holed silicalite-1 with mesoporosity and larger pores because the CNF-SDAs composite structure benefits the zeolite growth closely encompassing CNF inside the crystal structure. It also promotes the preferential formation of the orthorhombic phase vicinal to the CNF surface, namely, the surface of the formed internal holes or cracks, with the twin-type crystal size reduced as compared to the non-CNF-templated sample. On the contrary, the synthesis route that mixes CNF with SDAs–silicate composite ions tends to modify the twin-type crystal shape at the same time to form small but uniform well-crystallized particles with less holes or cracks and a dominative monoclinic phase. It was considered that both the inter-subunit structural defect and silanol defect whose content is increased with CNF addition influence the adsorptivity of MTBE and NDMA. Owing to the small twin-type crystal size, the smaller crystal subunits, and the favored short path from the surface of internal holes or cracks, the holed silicalite-1 derived from the CNF and SDA premixture assures the easiest access of adsorbate molecules to the most energetically favored sites and is most appropriate for the adsorption of both MTBE and NDMA among the examined zeolites.

A radical-mediated functionalization of allyl alcohol-derived partners with a variety of alkyl 1,4-dihydropyridines via photoredox/nickel dual catalysis is described. This transformation transpires with high linear and E-selectivity, avoiding the requirement of harsh conditions (e.g., strong base, elevated temperature). Additionally, using aryl sulfinate salts as radical precursors, allyl sulfones can also be obtained. Kinetic isotope effect experiments implicated oxidative addition of the nickel catalyst to the allylic electrophile as the turnover-limiting step, supporting previous computational studies.

Jinzhen oral liquid (JZ) is a classical traditional Chinese medicine formula used for the treatment of children lung disease. However, the effective substance of JZ is still unclear. In this study, we used lung injury rat model to study the protective effect of JZ, through UPLC-Q-TOF/MS detection coupled with metabolic research and network pharmacology analysis. Fortunately, 31 absorbed prototype constituents and 41 metabolites were identified or tentatively characterized based on UPLC-Q-TOF/MS analysis, and the possible metabolic pathways were hydroxylation, sulfation and glucuronidation. We optimized the data screening in the early stage of network pharmacology by collecting targets based on adsorbed constituents, and further analyzed the main biological processes and pathways. 24 selected core targets were frequently involved in reactive oxygen species metabolic process, dopaminergic synapse pathway and so on, which might play important roles in the mechanisms of JZ for the treatment of lung injury. Overall, the absorbed constituents and their possible metabolic pathways, as well as the absorbed constituent-target-disease network provided insights into the mechanisms of JZ for the treatment of lung injury. Further studies are needed to validate the biological processes and effect pathways of JZ. Keywords: Metabolic research, TCM, Network pharmacology

A sensitive technique for the measurement of warfarin and its metabolic enantiomers in human fluids such as urine and serum technique was developed by applying ultrasound-assisted dispersive liquid-liquid microextraction linked with poly(ethylene oxide)-mediated stacking in capillary electrophoresis. The parameters that influence extraction and stacking performance-the type of the extraction and dispersive solvents and their volume, extraction time, salt additives, sample matrix, solution pH, and the composition of background electrolyte stacking-were carefully studied and optimized based on the considering of obtaining the best detection sensitivity. Under the optimal extraction (30 μL C2H2Cl4 and 200 μL tetrahydrofuran in 1 mL of sample solution) and separation (0.5% PEO, 200 mM Tris-borate, pH 8.5, and 5 mM dimethyl-β-cyclodextrin) conditions, the enrichment factors of D-/L-warfarins and D-/L-7-OH warfarins covered from 1758 to 1859 and their limits of detection ranged from 0.34 to 0.38 nM. Calibration-related results exhibited acceptable linearity with the coefficient of determination higher than 0.99; the relative standard deviations of the peak area were determined to 4.1%–6.3% (n = 3). The recovery of four separated analytes spiked in samples of urine and serum was found to be 93%–110% and 95%–109%, respectively. We revealed that ultrasound-assisted dispersive liquid-liquid microextraction with poly(ethylene oxide)-mediated stacking in capillary electrophoresis could be a prompt and practical method for quantifying the levels of warfarin and its metabolic enantiomers in real-world samples, especially in biological fluids.

The enhancement of surface plasmon-coupled emission (SPCE) by the synergistic effect of silver nanocubes (AgNCs) and graphene oxide (GO) on gold film has been observed with the enhancement factor over 30. The enhancement mechanisms were investigated through simulating the electromagnetic (EM) field patterns of near field and testing different concentration of AgNCs and thickness of dye layer. The enhancement was mainly triggered by the high electromagnetic field of AgNCs, the interaction between localized surface plasmons (LSP) and propagating surface plasmons (PSP) and the assistance of GO. This synergistic enhancement strategy provides a simple way to increase SPCE signal and enable develop a new fluorescence-based detection system.

Humification of Sphagnum occurs in peat bogs and locks up carbon as peat. Useful indicators and methods of humification can reflect the process of peat formation to some extent. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV/Vis spectra and excitation-emission matrix (EEM) spectra coupled with parallel factor (PARAFAC) analysis were applied to characterize the humification of Sphagnum, peat, dissolved organic matter (DOM) and chlorophyll with depth. The TEM results showed that chlorophyllous cells were almost completely degraded under the brown layer (BL), while Sphagnum hyaline cells demonstrated little degradation, and their structure could be observed even in peat. EEM spectra coupled with PARAFAC analysis is a good way to study chlorophyll in peat, and chlorophyll can be a useful indicator in humus studies. The peat had a relatively high chlorophyll content, which was negatively correlated with fulvic-like components and positively correlated with easily biodegradable organic matter. The parameters of samples from different layers fell into four groups, i.e., fulvic-like components, humification, humic-like components and/or protein-like components, easily biodegradable organic matter, and a combination or transition of the fluorescent substance of Sphagnum and humic-like components. The collapsed and defoliated layer (CDL) may be the layer in which the process of humification begins, and the humification of the grass root layer (GRL) was similar to that of peat. The degree of humification gradually increased from peat at 0–5 cm (P0-5) to peat at 10–15 cm (P10-15) and had no regular trend with depth from peat at 15–20 cm (P15-20) to peat at 25–30 cm (P25-30).

Caffeine is a substance that is consumed worldwide, and it may exert neuroprotective effects against various cerebral insults, including neurotrauma, which is the most prevalent injury among military personnel. To investigate the effects of caffeine on high-intensity blast wave-induced severe blast injury in mice, three different paradigms of caffeine were applied to male C57BL/6 mice with severe whole body blast injury (WBBI). The results demonstrated that chronic caffeine treatment alleviated blast-induced traumatic brain injury (bTBI); however, both chronic and acute caffeine treatments exacerbated blast-induced lung injuries and, more importantly, increased both the cumulative and time-segmented mortalities postinjury. Interestingly, withdrawing caffeine intake preinjury resulted in favorable outcomes in mortality and lung injury, similar to the findings in water-treated mice, and had the trend to attenuate brain injury. These findings demonstrated that although drinking coffee or caffeine preparations attenuated blast-induced brain trauma, these beverages may place personnel in the battlefield at high risk of casualties, which will help us re-evaluate the therapeutic strategy of caffeine application, particularly in multiple-organ-trauma settings. Furthermore, these findings provided possible strategies for reducing the risk of casualties with caffeine consumption, which may help to change the coffee-drinking habits of military personnel.

Monolithic graphene oxide (GO) and reduced GO (rGO) aerogel is recently receiving a great deal of concern as a promising adsorbent, whose structure and surface properties, however, are anticipated to be improved and adapted to the adsorption of organic contaminants with various polarities and ionic properties. Herein, super strong and hydrophilic cellulose nanofiber (CNF) was exploited as a cross-linker to interweave in between rGO layers so as to tune and balance the structural and surface properties (hydrophilicity and hydrophobicity) of the monolith. It was found that mechanical property of the monolith changes stepwise with the addition of CNF and can be greatly improved by proportion with CNF irrespective of a little sacrifice in electrical conductivity. Filling and further formation of aggregating bundle structure of CNFs in rGO monolith gradually decreases porosity at compensation of a slight increase in monolithic volume. CNF plays a critical role in separating rGO layers, leading to formation of the exposed and uniformly dispersed rGO layers in the monoliths. It can increase the amount of oxygen containing groups at the same time to generate carbonized moieties, thus ameliorating both hydrophilicity and hydrophobicity of the monolithic aerogel. The unique structural change and improved amphiphile surface property due to the addition of CNF can greatly enhance affinity of the hybridized monolith toward the adsorption of not only hydrophilic (both anionic and cationic) dyes but also hydrophobic organic oil.

In order to find deep-seated deposit, there is a need to develop non-traditional surface geochemistry. Geogas is of particular interest. Particles transported by geogas from the deeply concealed deposits potentially hold great information. This study investigates particles carried by ascending gas flows from the Bairendaba lead-zinc deposit. This deposit is covered by a thick exotic substance, which hinders probing the ore body directly. The samples were collected using a static sampling method and were analysed by transmission electron microscopy (TEM) to observe particle features (such as shape, component, size, structure, and form of polymerization); these particles contain information on buried deposits. Numerous Pb-, Zn-, and Cu-bearing particles, as well as particles containing other metal compounds, occur as individuals or aggregates in the ascending gas flows. Most particles have a large oxygen (O) content; this is likely caused by the course of gas flows ascending from the deep ore body to the ground surface. Sulphur (S) is commonly associated with Pb, Cu, As, Fe, and Sb and occurs as sulphate in this deposit. Most metallic elements occur as sulphate, oxide, and carbonate in the detected particles. In contrast to the samples collected in the peripheral area, samples collected from the concealed deposit include numerous particles containing metallogenic elements, although particles containing major elements can be found in both areas. Moreover, the trend of each Pb- or Zn-bearing particle along a unique sampling line is directly related to the distribution of the corresponding ore bodies; this indicates that the particles were generated at a certain depth, carried by the ascending gas flow and directly provide important information regarding the concealed ore bodies. The anomalous area can be used as a basis for further prospect analysis and improve the prospecting success rate.

An efficient synthesis of a variety of quinazolinone derivatives via a direct cyclization reaction between commercially available anthranils and cyclic amines is described. The developed transformation proceeds with the merits of high step- and atom-efficiency, a broad substrate scope, and good to excellent yields, without additional catalysts, and offers a practical way for the preparation of rutaecarpine and its derivatives with structural diversity.

We propose an efficient liquid-phase hydrogenolysis system for the selective cleavage of an α-O-4 lignin model compound, benzyl phenyl ether (BPE), under mild conditions. By employing EtOH/H2O as co-solvent and a carbon black supported nickel (Ni/CB) catalyst in the presence of NaBH4 as the hydrogen source, BPE hydrogenolysis exhibited over 99% BPE conversion along with very high toluene (46%) and phenol (45%) yields. The catalytic performance of the Ni/CB catalyst was compared with those of various noble metal catalysts (Pd/C, Ru/C and Rh/C) for BPE hydrogenolysis. The results disclosed that the Ni/CB catalyst performs better than noble metal catalysts and exhibited higher selectivity for toluene and phenol under mild reaction conditions (80 °C). In the Ni/CB catalyst, the CB support assists in obtaining a higher yield of toluene and phenol and offers complete conversion of BPE compared to an activated carbon support (34% BPE conversion) in Ni/AC. The Ni/CB catalyst was synthesized by an impregnation method and fully characterized using various characterization techniques (XRD, SEM, TEM, XPS, ICP and FT-IR).

We present a cryo-EM structure of the monomeric light-harvesting-reaction center (LH1-RC) core complex from photosynthetic purple bacterium Rhodobacter (Rba.) sphaeroides at 2.9 Å resolution. The LH1 complex forms a C-shaped structure composed of 14 αβ-polypeptides around the RC with a large ring opening. From the cryo-EM density map, a previously unrecognized integral membrane protein, referred to as protein-U, was identified. Protein-U has a U-shaped conformation near the LH1-ring opening and was annotated as a hypothetical protein in the Rba. sphaeroides genome. Deletion of protein-U resulted in a mutant strain that expressed a much-reduced amount of the dimeric LH1-RC, indicating an important role for protein-U in dimerization of the LH1-RC complex. PufX was located opposite protein-U on the LH1-ring opening, and both its position and conformation differed from that of previous reports of dimeric LH1-RC structures obtained at low-resolution. Twenty-six molecules of the carotenoid spheroidene arranged in two distinct configurations were resolved in the Rba. sphaeroides LH1 and were positioned within the complex to block its pores. Our findings offer a new view of the core photocomplex of Rba. sphaeroides and the connections between structure and function in bacterial photocomplexes in general.

Rhodospirillum (Rsp.) rubrum is one of the most widely used model organisms in bacterial photosynthesis. This purple phototroph is characterized by the presence of both rhodoquinone (RQ) and ubiquinone as electron carriers and bacteriochlorophyll (BChl) a esterified at the propionic acid side chain by geranylgeraniol (BChl aG) instead of phytol. Despite intensive efforts, the structure of the light-harvesting-reaction center (LH1-RC) core complex from Rsp. rubrum remains at low resolutions. Using cryo-EM, here we present a robust new view of the Rsp. rubrum LH1-RC at 2.76 A resolution. The LH1 complex forms a closed, slightly elliptical ring structure with 16 αβ-polypeptides surrounding the RC. Our biochemical analysis detected RQ molecules in the purified LH1-RC, and the cryo-EM density map specifically positions RQ at the QA site in the RC. The geranylgeraniol side chains of BChl aG coordinated by LH1 β-polypeptides exhibit a highly homologous tail-up conformation that allows for interactions with the bacteriochlorin rings of nearby LH1 α-associated BChls aG. The structure also revealed key protein-protein interactions in both N- and C-terminal regions of the LH1 αβ-polypeptides, mainly within a face-to-face structural subunit. Our high-resolution Rsp. rubrum LH1-RC structure provides new insight for evaluating past experimental and computational results obtained with this old organism over many decades and lays the foundation for more detailed exploration of light-energy conversion, quinone transport, and structure-function relationships in this pigment-protein complex.

Sulfonium salts bearing a positively charged sulfur atom with three organic substituents have intrigued chemists for more than a century for their unusual structures and high chemical reactivity. These compounds are known to undergo facile single-electron reduction to emerge as a valuable and alternative source of aryl radicals for organic synthesis. However, the generation of non-stabilized alkyl radicals from sulfonium salts has been a challenge for several decades. Here we report the treatment of S-(alkyl) thianthrenium salts to generate non-stabilized alkyl radicals as key intermediates granting the controlled and selective outcome of the ensuing reactions under mild photoredox conditions. The value of these reagents has been demonstrated through the efficient construction of alkylboronates and other transformations, including heteroarylation, alkylation, alkenylation, and alkynylation. The developed method is practical, and provides the opportunity to convert C–OH bond to C–B and C–C bonds., The generation of non-stabilized alkyl radicals from sulfonium salts has been a challenge for several decades. Here, the authors show the treatment of S-(alkyl) thianthrenium salts, which can generate non-stabilized alkyl radicals as key intermediates that enable controlled and selective reactions under mild photoredox conditions.

Photosynthetic electron transfers occur through multiple components ranging from small soluble proteins to large integral membrane protein complexes. Co-crystallization of a bacterial photosynthetic electron transfer complex that employs weak hydrophobic interactions was achieved by using high-molar-ratio mixtures of a soluble donor protein (high-potential iron-sulfur protein, HiPIP) with a membrane-embedded acceptor protein (reaction center, RC) at acidic pH. The structure of the co-complex offers a snapshot of a transient bioenergetic event and revealed a molecular basis for thermodynamically unfavorable interprotein electron tunneling. HiPIP binds to the surface of the tetraheme cytochrome subunit in the light-harvesting (LH1) complex-associated RC in close proximity to the low-potential heme-1 group. The binding interface between the two proteins is primarily formed by uncharged residues and is characterized by hydrophobic features. This co-crystal structure provides a model for the detailed study of long-range trans-protein electron tunneling pathways in biological systems., The high potential iron-sulfur (HiPIP) proteins are direct electron donors to the light-harvesting-reaction center complexes (LH1-RC) in photosynthetic β- and γ-Proteobacteria. Here, the authors present the 2.9 Å crystal structure of the HiPIP-bound LH1-RC complex from the thermophilic purple sulfur bacterium Thermochromatium tepidum and discuss mechanistic implications for the electron transfer pathway.

Ilicis Rotundae Cortex (IRC) consists of the bark of Ilex rotunda Thunb, and its chemical constituents mainly include flavonoid glycosides, phenols, and triterpenoid saponins. In this study, a preliminary analysis was performed to identify and obtain the chemical components from IRC to better control the quality of the medicinal materials and provide a chemical basis for the study of the efficacy of the active components. Simple and efficient sample pretreatment and ultrasonic-assisted extraction methods were used to analyze the mass spectrum fragments and fracture modes in the anion mode by UPLC-Q-TOF-MS/MS. Using a two-step strategy, the neutral loss, diagnostic ions, and characteristic fragments were studied to screen diverse skeletons and substitutions, and the possible compounds were identified by comparison with databases. The representative compounds were compared with the standard, and the mass spectrogram was found to match perfectly. Thus, our findings reveal that this method is feasible and reliable and can be used to analyze the chemical components of IRC. We identified 105 compounds, including 22 triterpenoid saponins, 15 chlorogenic acids, 33 phenylpropanoids and phenylpropanosides, 3 iridoids, 1 flavonoid, 10 lignans, 12 glycosides, and 9 other compounds. This method lays the foundation for further elucidating the pharmacodynamics of IRC and provides a practical method for the identification of IRC.

The core light-harvesting complexes (LH1) in bacteriochlorophyll (BChl) b-containing purple phototrophic bacteria are characterized by a near-infrared absorption maximum around 1010 nm. The determinative cause for this ultra-redshift remains unclear. Here, we present results of circular dichroism (CD) and resonance Raman measurements on the purified LH1 complexes in a reaction center-associated form from a mesophilic and a thermophilic Blastochloris species. Both the LH1 complexes displayed purely positive CD signals for their Qy transitions, in contrast to those of BChl a-containing LH1 complexes. This may reflect differences in the conjugation system of the bacteriochlorin between BChl b and BChl a and/or the differences in the pigment organization between the BChl b- and BChl a-containing LH1 complexes. Resonance Raman spectroscopy revealed remarkably large redshifts of the Raman bands for the BChl b C3-acetyl group, indicating unusually strong hydrogen bonds formed with LH1 polypeptides, results that were verified by a published structure. A linear correlation was found between the redshift of the Raman band for the BChl C3-acetyl group and the change in LH1-Qy transition for all native BChl a- and BChl b-containing LH1 complexes examined. The strong hydrogen bonding and π–π interactions between BChl b and nearby aromatic residues in the LH1 polypeptides, along with the CD results, provide crucial insights into the spectral and structural origins for the ultra-redshift of the long-wavelength absorption maximum of BChl b-containing phototrophs.

The light-harvesting-reaction center complex (LH1-RC) from the purple phototrophic bacterium Thiorhodovibrio strain 970 exhibits an LH1 absorption maximum at 960 nm, the most red-shifted absorption for any bacteriochlorophyll (BChl) a-containing species. Here we present a cryo-EM structure of the strain 970 LH1-RC complex at 2.82 Å resolution. The LH1 forms a closed ring structure composed of sixteen pairs of the αβ-polypeptides. Sixteen Ca ions are present in the LH1 C-terminal domain and are coordinated by residues from the αβ-polypeptides that are hydrogen-bonded to BChl a. The Ca2+-facilitated hydrogen-bonding network forms the structural basis of the unusual LH1 redshift. The structure also revealed the arrangement of multiple forms of α- and β-polypeptides in an individual LH1 ring. Such organization indicates a mechanism of interplay between the expression and assembly of the LH1 complex that is regulated through interactions with the RC subunits inside., Here the authors report a cryo-EM structure of the light-harvesting-reaction center complex (LH1- RC) from the purple phototrophic bacterium Thiorhodovibrio strain 970, providing insights into the mechanisms that underlie the absorbance properties of both the LH1 and the RC of this spectrally unusual purple bacterium.

Progress has been made in overcoming antibody-mediated rejection of porcine xenografts by deleting pig genes that produce unique carbohydrate epitopes. Pigs deficient in galactose α-1,3 galactose (gene modified: GGTA1) and neu5Gc (gene modified: CMAH) have reduced levels of human antibody binding. Previously we identified α-fucose as a glycan that was expressed in high levels on cells of GGTA1/CMAH KO pigs. To validate the α-fucose phenotype observed previously we compared lectin affinity toward human and pig serum glycoproteins by dot blot analysis and confocal microscopy. Human anti-fucose antibody isolated by affinity chromatography was tested for specificity to L-fucose by custom macroarray. The affinity and cytotoxicity of the isolated human anti-fucose antibody toward human and GGTA1/CMAH KO pig PBMCs was determined by flow cytometry. Dot blot and confocal analysis support out previous findings that α-fucose is more highly expressed in pigs than humans. Pig kidney glomeruli and tubules contain abundant α-fucose and may represent focal sites for anti-α-fucose antibody binding. The Isolated human anti-fucose IgA, IgG and IgM bound to GGTA1/CMAH KO pig PBMC and were cytotoxic. Interestingly, the isolated human IgG cross reacted with the methyl pentose, L-rhamnose. Human anti-fucose antibody bound and was cytotoxic to GGTA1/CMAH KO pig peripheral blood monocytes. We have shown that α-fucose is an abundant target for cytotoxic human antibody in the organs of genetically modified pigs important to xenotransplantation.

Blastochloris tepida is a newly described thermophilic purple bacterium containing bacteriochlorophyll b. Using purified light-harvesting 1 reaction center (LH1-RC) core complexes from Blc. tepida,...

In this work, we present a simple method to improve the thermoelectric performance of the RF sputtered bismuth telluride films by raising the power of deposition. The as-deposited samples synthesized under different powers were investigated and compared. It shows that the films prepared under relatively higher power conditions exhibit much higher electrical conductivity to result in a greater power factor accompanied with a minor drop in the Seebeck coefficients. A relationship is established between the improvement in thermoelectric performance and the decrease in crystallinity, which might also reduce the thermal conductivity. A maximum power factor of 5.65 &times, 10&minus, 4 W&middot, m&minus, 1&middot, K&minus, 2 at 470 K is obtained for the sample deposited under 50 W with its Seebeck coefficient being &minus, 105 &mu, V/K. The temperature-dependent behaviors of the samples are also looked into and discussed. This work might offer an in-situ and cost-effective approach to improve the performance of thermoelectric materials.

The semihydrogenation of phenylacetylene to styrene represents an important process for optimizing the polystyrene production and also a model reaction for the evaluation of selective hydrogenation catalysts. Although the alloying strategy and surface engineering for noble metal (particularly for Pd) catalysts can effectively inhibit the overhydrogenation of styrene, the selectivity of phenylacetylene semihydrogenation to styrene is generally below 95% near the full conversion. Here, we demonstrate the electronic modulation of Pd-based bimetallic nanocluster catalysts based on the strong metal-support interactions for improving the catalytic selectivity for phenylacetylene semihydrogenation. A series of Pd-M (M = Fe, Co, Ni, Cu, Ga) bimetallic nanoclusters of ∼2 nm are immobilized on mesoporous sulfur-doped carbon (meso_S-C) supports, which exhibit a high selectivity of >97% for the semihydrogenation of phenylacetylene to styrene. The strong interaction between metal and the meso_S-C supports enables the modulation of electronic structure of the bimetallic nanoparticles and thus leads to the selectivity enhancement for the phenylacetylene semihydrogenation.

Luminescent metal-organic frameworks (MOFs) have been extensively investigated as sensors for detection of various compounds. In this work, 5,5',5''-((benzene-1,3,5-tricarbonyl)tris(azanediyl))triisophthalic acid (H6L) and 1,3,5-tri(1H-imidazol-1-yl)benzene (tib) were reacted with Cd(NO3)2·4H2O under solvothermal conditions to generate a MOF [Cd3(H2O)3(L)(tib)2]·5DMA·4H2O (1) (DMA = N,N-dimethylacetamide). Single-crystal X-ray diffraction analysis revealed that 1 is a 2-fold interpenetrated three-dimensional framework composed of Cd-L and Cd-tib two-dimensional networks. Furthermore, its fluorescence and sensing capability towards common organic compounds were explored. The results indicate that 1 could function as a fluorescent probe for nitro-aromatic compounds, especially for 2,4,6-trinitrophenol (TNP) and 4-nitrophenol (4-NP).

AMD3100 is a small-molecule inhibitor of the C-X-C motif chemokine ligand 12/C-X-C chemokine receptor type 4 (CXCL12/CXCR4) axis, while its role in aggrecan metabolism is unclear. We hypothesized that the AMD3100 modulates the transforming growth factor-β1 (TGF-β1)-induced expression of tissue inhibitor of metalloproteinase-3 (TIMP-3) in chondrocytes. We evaluated expression of CXCL12/CXCR4 and TIMP-3 in the knee joints of rats with and without osteoarthritis (OA) by immunohistochemistry, immunofluorescence, Western blotting, and enzyme-linked immunosorbent assay (ELISA). The rats were divided into sham control, destabilization of the medial meniscus/AMD3100-treated (DMM/AMD3100-treated), and DMM/phosphate-buffered saline (PBS)-treated groups. After 6 weeks, the rats were euthanized and subjected to histological and immunohistochemical analyses. Also, interleukin (IL)-1-pretreated primary chondrocytes were cultured in the presence of empty control (−, −), CXCL12a (+,−), CXCL12a + small interfering RNA (siRNA) CXCR4 (+,+), or CXCL12a + siNC (+NC), and the expression levels of target markers were evaluated by Western blotting and real-time reverse transcription PCR (RT-PCR). The CXCL12/CXCR4 levels were higher, and the expression of TIMP-3 was lower, in the OA rats compared to the healthy control rats. The rats in the DMM/AMD3100-treated group revealed a markedly decreased immunological response and mild pathology. Treatment with CXCL12a increased expression of aggrecan and disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS-5) and suppressed that of TIMP-3 in IL-1-pretreated primary chondrocytes. TGF-β1 increased expression of TIMP-3, and this increase was reversed by CXCL12a via the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Moreover, these effects were inhibited by the CXCR4 antagonist AMD3100 and the PI3K inhibitor {"type":"entrez-nucleotide","attrs":{"text":"LY303511","term_id":"1257646067","term_text":"LY303511"}}LY303511. In conclusion, inhibition of the CXCL12a/CXCR4 signaling axis maintained TIMP-3 expression via the PI3K/Akt pathway. Our findings provide insight into the mechanism by which AMD3100 prevents OA.

With increasing and abuse of antibiotics, selective and sensitive detection of specific antibiotics is required. In this work, we report novel Cd(II)-based metal–organic framework (MOF) [Cd2(L)(bpda)2]·4DMF·4H2O·MeOH (1) by using mixed organic ligands 3,3′,5,5′-tetra(1H-imidazol-1-yl)biphenyl (L) and 4,4′-carbonyldibenzoic acid (H2bpda). MOF 1 transformed to [Cd2(L)(bpda)2]·3DMF·H2O (2) at room temperature via a single-crystal-to-single-crystal process, and the emission of 2 can be quenched efficiently by trace amounts of NFs (nitrofurazone, NZF; nitrofurantoin, NFT; furazolidone, FZD) antibiotics with detection limits of 252 ppb, 465 ppb, 969 ppb for NZF, NFT and FZD, respectively, even in the presence of other competing antibiotics such as sulfadiazine (SDZ). The results show that 2 is a potential luminescent sensor for antibiotics.

An efficient synthesis of a variety of dibenzofuran derivatives via Cu-catalyzed cyclization diaryliodonium salts in water is achieved. Various dibenzofuran derivatives could be obtained in good to excellent yields via this oxygen–iodine exchange approach. A concise synthesis of organic semiconducting material molecule has been achieved using this method.

Titanium dioxide (TiO2) nanoparticles (NPs) are used abundantly as food additives (E171). For the purpose of risk assessment, it is imperative to understand the behavior of these nanoparticles in a food relevant environment, and their consequent toxicology impacts. However, most of such studies use model TiO2 NPs (P25) as substitutes for E171. To understand the suitability of this approach, we investigated the functional behavior of E171 and P25 in solutions of bovine serum albumin (BSA) and sucrose as model food ingredients. Our data showed that E171 were better dispersed in BSA than P25. In sucrose, E171 displayed a reduction in agglomerated size while P25 agglomerated extensively. Adsorption studies showed that P25 attracted more pronounced corona formation per unit mass of material compared to E171. In vitro sedimentation, diffusion and dosimetry (ISDD) results demonstrated that the time-weighted dosage of E171 was more than two-folds higher than P25, implying that any test performed using P25 to model E171 would underestimate actual dosage and potential toxicity. Taken collectively, this study demonstrated the specificity of TiO2 nanoparticle interaction with food ingredients, and the importance of using food-grade E171 TiO2 for food-relevant toxicological assessments. Accepted version

A cobalt-catalyzed C(sp2)–H alkoxylation of 1-naphthylamine derivatives has been disclosed, which represents an efficient approach to synthesize aryl ethers with broad functional group tolerance. It is noteworthy that secondary alcohols, such as hexafluoroisopropanol, isopropanol, isobutanol, and isopentanol, were well tolerated under the current catalytic system. Moreover, a series of biologically relevant fluorine-aryl ethers were easily obtained under mild reaction conditions after the removal of the directing group.

The effects of high Cu, Pb, and Zn concentrations on pigments of Pinus massoniana L. (PML) growing near the Dabaoshan Pb-Zn polymetallic mine were evaluated. A total of 19 samples of PML needles and 15 samples of soil were collected near the mine and at a nearby background site to compare heavy metal (HM; Zn, Cu, Pb) accumulations. A 2D scatter plot was used to study the relationships between the pigments and each metal element. PML needles collected from the mining area had a significantly higher content of Pb (24.5 mg/kg) and Cu (26.1 mg/kg) than needles collected from the background site (Pb: 2.8 mg/kg, Cu: 6.7 mg/kg). The HM concentrations in the needles were positively correlated with the pigment contents (chlorophyll a, chlorophyll b and carotenoids) . This suggests that PML can adapt to HM stress and even promote growth within a certain range. In contrast, when the HM content in needles reached very high values (Cu: 50 mg/kg, Pb: 60 mg/kg, and Zn: 110 mg/kg), the normal physiological and biochemical functions were hindered. PML is highly resistant to HM pollution, making it a candidate for reforestation and restoration of Pb and other HMs in mine areas.

Halorhodospira (Hlr.) halochloris is a unique phototrophic purple bacterium because it is a triple extremophile—the organism is thermophilic, alkalophilic, and halophilic. The most striking photosynthetic feature of Hlr. halochloris is that the bacteriochlorophyll (BChl) b-containing core light-harvesting (LH1) complex surrounding its reaction center (RC) exhibits its LH1 Qy absorption maximum at 1016 nm, which is the lowest transition energy among phototrophic organisms. Here we report that this extraordinarily red-shifted LH1 Qy band of Hlr. halochloris exhibits interconvertible spectral shifts depending on the electrostatic charge distribution around the BChl b molecules. The 1016 nm band of the Hlr. halochloris LH1-RC complex was blue-shifted to 958 nm upon desalting or pH decrease but returned to its original position when supplemented with salts or pH increase. Resonance Raman analysis demonstrated that these interconvertible spectral shifts are not associated with the strength of hydrogen-bonding interactions between BChl b and LH1 polypeptides. Furthermore, circular dichroism signals for the LH1 Qy transition of Hlr. halochloris appeared with a positive sign (as in BChl b-containing Blastochloris species) and opposite those of BChl a-containing purple bacteria, possibly due to a combined effect of slight differences in the transition dipole moments between BChl a and BChl b and in the interactions between adjacent BChls in their assembled state. Based on these findings and LH1 amino acid sequences, it is proposed that Hlr. halochloris evolved its unique and tunable light-harvesting system with electrostatic charges in order to carry out photosynthesis and thrive in its punishing hypersaline and alkaline habitat.

Separation techniques are promising for the detection of adamantane analogs with various functional groups. The derivatization of adamantane analogs with chromophores or fluorophores should be conducted using a separation technique combined with a common ultraviolet–visible or fluorescence detector. However, limited research has been conducted on underivatized adamantane analogs. Therefore, we present a highly rapid and sensitive method for detecting underivatized adamantane analogs by integrating ultrasound-assisted dispersive liquid–liquid microextraction (UADLLME), field-amplified sample stacking (FASS)-related capillary electrophoresis (CE), and capacitively coupled contactless conductivity detection (C4D). In the proposed system, UADLLME is used for sample clean up and analyte enrichment, whereas FASS-related CE provides on-line concentration of underivatized adamantane analogs during CE separation. A mixture of memantine (MT), amantadine (AT), and rimantadine (RT) was separated at baseline within 8 min through the application of optimized UADLLME (mixing extraction solvent, 50 μL of 1,1,2,2-tetrachloroethane (C2H2Cl4) and dispersive solvent, 200 μL of acetonitrile; mixing solution was injected into 1 mL of the sample solution at pH 12.5), FASS (buffer, 1.5 M acetic acid; additive, 0.05 mM β-cyclodextrin; pH 2.5), and C4D (amplitude, 2 Vpp; frequency, 500 kHz). The calibration curve exhibited acceptable linearity, with a coefficient of determination higher than 0.99. The limits of detection (signal-to-noise ratio of 3) were estimated to be 0.9, 1.0, and 1.2 nM for MT, AT, and RT, respectively. The relative standard deviations of peak areas varied from 8.9% to 9.3% (n = 5), whereas the sensitivity improvement of three underivatized adamantane analogs ranged from 1342 to 1766. The feasibility and accuracy of the present method for the determination of MT, AT, and RT in human serum and urine was satisfactorily confirmed by the excellent recovery and relative error. The proposed method exhibited high enrichment factors and offers excellent precision, high accuracy, and a short analysis time.

In present study, the antimicrobial compounds (AMCs) from Paecilomyces cicadae (P. cicadae) were initially purified, and its antimicrobial mechanism was investigated. The results showed that the molecular weight of AMCs in crude protein extracts was below 10 kDa. The minimum inhibitory concentration (MIC) of crude protein extracts against Escherichia coli (E. coli) was 0.050 mg/mL. After E. coli was treated by crude protein extracts, we found that it could disrupt the structure of cell membrane, change the content of whole-cell or membrane proteins. In addition, crude protein extracts with certain concentrations also could effectively interact with bacterial DNA. Quantitative real-time PCR (qRT-PCR) results indicated that the expression levels of flagellar biosynthesis genes fliP, fliO, flgD and flhB were down-regulated, whereas dppF and dnaJ which are associated with the transport across the membrane and the interaction with dnaK, respectively, were up-regulated when E. coli was exposed to crude protein extracts. The present findings suggested that AMCs from P. cicadae showed a potential value for the development of antibacterial products.

Cost-effective nonprecious metal nanostructures are considered as highly promising electrocatalysts towards oxygen evolution reaction (OER). Optimizing their morphologies is an efficient strategy to enhance the electroactivity and durability of various electrocatalysts for practical application. Herein, porous cobalt carbonate hydroxide nanospheres (CoCO3 PNSs) are successfully synthesized by using calcium carbonate (CaCO3) nanospheres as a reaction precursor and self-template via a facile precipitation transformation method. Mainly, the solubility constant [Ksp (CoCO3) = 1.4 × 10−13] of CoCO3 is much lower than that [Ksp (CaCO3) = 2.8 × 10−9] of CaCO3, resulting in the successful transformation of CaCO3 nanospheres to CoCO3 PNSs. Physical characterizations reveal that CoCO3 PNSs consist of many tiny subnanorods (length of 50 nm, diameter of 5 nm), which have a high surface area and abundant channels between subnanorods. Compared to irregular cobalt carbonate hydroxide nanoparticles, CoCO3 PNSs reveal enhanced OER performance in KOH solution, including a low overpotential of 310 mV and a small Tafel slope of 56 mV dec−1.