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Thrombogenic reaction, aggressive smooth muscle cell (SMC) proliferation, and sluggish endothelial cell (EC) migration onto bioinert metal vascular stents make poststenting reendothelialization a dilemma. Here, we report an easy to perform, biomimetic surface engineering strategy for multiple functionalization of metal vascular stents. We first design and graft a clickable mussel-inspired peptide onto the stent surface via mussel-inspired adhesion. Then, two vasoactive moieties [i.e., the nitric-oxide (NO)-generating organoselenium (SeCA) and the endothelial progenitor cell (EPC)-targeting peptide (TPS)] are clicked onto the grafted surfaces via bioorthogonal conjugation. We optimize the blood and vascular cell compatibilities of the grafted surfaces through changing the SeCA/TPS feeding ratios. At the optimal ratio of 2:2, the surface-engineered stents demonstrate superior inhibition of thrombosis and SMC migration and proliferation, promotion of EPC recruitment, adhesion, and proliferation, as well as prevention of in-stent restenosis (ISR). Overall, our biomimetic surface engineering strategy represents a promising solution to address clinical complications of cardiovascular stents and other blood-contacting metal materials.

Intracellular antigen labeling and manipulation by antibodies have been long-thought goals in the field of cell research and therapy. However, a central limitation for this application is that antibodies are not able to penetrate into the cytosol of living cells. Taking advantages of small sizes and unique structures of the single-domain antibodies, here, we presented a novel approach to rapidly deliver the nanobody/variable domain of heavy chain of heavy-chain antibody (VHH) into living cells via introducing its coding mRNA, which was generated by in vitro transcription. We demonstrated that actin-green fluorescent proteins (GFP) and Golgi-GFP can be recognized by the anti-GFP nanobody/VHH, vimentin can be recognized by the anti-vimentin nanobody/VHH, and histone deacetylase 6 (HDAC6) can be recognized by the anti-HDAC6 nanobody/VHH, respectively. We found that the anti-GFP nanobody expressed via in vitro-transcribed (IVT) mRNA can be detected in 3 h and degraded in 48 h after transfection, whereas the nanobody expressed via plasmid DNA, was not detected until 24 h after transfection. As a result, it is effective in delivering the nanobody through expressing the nanobody/VHH in living cells from its coding mRNA.

This study aims to explore the effects of exosomes, secreted by retinal pigment epithelial (RPE) cells under oxidative stress (OS), on apoptosis and inflammation of normal RPE cells. Exosomes secreted by normal RPE cells (named as exo) and rotenone (2.5 µmol/L) stimulated RPE cells (named as rot-exo) were isolated and extracted by multi-step differential centrifugation for morphology observation under a transmission electron microscopy. pcDNA3.1a, pcDNA3.1a-Apaf1, and p3xFlag-CMV-caspase-9 plasmids were constructed and transfected into ARPE-19 cells. Exosomes secreted by ARPE-19 cells were injected into the vitreous body of rats to verify the effect of Apaf1 and caspase-9 on cell apoptosis and inflammation. Co-immunoprecipitation was applied to clarify the interaction of Apaf1 with caspase-9. Exosomes secreted by rotenone stimulated ARPE-19 cells could induce cell apoptosis, oxidative injury, and inflammation in ARPE-19 cells. Exosomes secreted under OS can damage retinal functions of rats and have upregulated expression of Apaf1. Overexpression of Apaf1 in exosomes secreted under OS can cause the inhibition of cell proliferation, the increase of cell apoptosis and elicitation of inflammatory response in ARPE-19 cells. Exosomes derived from ARPE-19 cells under OS regulate Apaf1 expression to increase cell apoptosis and to induce oxidative injury and inflammatory response through a caspase-9 apoptotic pathway.

Tuberculosis (TB), caused by Mycobacterium tuberculosis (M. tuberculosis), is one of the most fatal diseases in the world. Methylenetetrahydrofolate reductase (MTHFR) catalyzes the production of 5-methyltetrahydrofolate (5-CH3-THF), which is required for the de novo biosynthesis of methionine in bacteria. In this study, we identified Rv2172c as an MTHFR in M. tuberculosis through in vitro and in vivo analyses and determined that the protein was essential for the in vitro growth of the bacterium. Subsequently, we constructed rv2172c R159N and L214A mutants in M. tuberculosis, and found that these mutants were more sensitive to the antifolates para-aminosalicylic acid (PAS) and sulfamethoxazole (SMX). Combining biochemical and genetic methods, we found that rv2172c R159N or L214A mutation impaired methionine production, leading to increased susceptibility of M. tuberculosis to PAS, which was largely restored by adding exogenous methionine. Moreover, overexpression of rv2172c in M. tuberculosis could increase methionine production and lead to PAS resistance. This research was the first to identify an MTHFR in M. tuberculosis and revealed that the activity of this enzyme was associated with susceptibility to antifolates. These findings have particular value for anti-tubercular drugs design for the treatment of drug-resistant TB.

Angiogenesis is a complex process, which involves the sprouting of new blood vessels from pre-existing vasculature. Pathological retinal angiogenesis can lead to vision loss and even blindness. Cyclin-dependent kinase 1 (CDK1) is involved in regulation of the cell cycle and is reported to contribute to tumor progression. However, the role of CDK1 in retinal angiogenesis is largely unknown. The purpose of the present study was to investigate the role of CDK1 in retinal angiogenesis. Western blotting, reverse transcription-quantitative PCR (RT-qPCR) analysis, immunofluorescence and immunohistochemistry were used to evaluate the expression of CDK1 in pathological angiogenesis using an oxygen-induced retinopathy (OIR) mouse model. Small interfering (si)RNA sequences against CDK1 were synthesized and incubated with retinal cells. The efficiency of knockdown was confirmed by western blot and RT-qPCR assays. The effect of CDK1 siRNAs on angiogenesis in vitro was investigated using EdU cell proliferation, cell migration and tube formation assays. Subsequently, flow cytometry was used to assess the effects of CDK1 siRNAs on cell cycle distribution and on the induction of apoptosis. The expression levels of cell cycle- and apoptosis-related genes were detected using western blotting. CDK1 was overexpressed in pathological retinal angiogenesis. CDK1 siRNAs inhibited human umbilical vein endothelial cell proliferation, migration and tube formation. The possible mechanisms involved the induction of cell cycle arrest at the G2/M phase and the induction of apoptosis via an increase in the expression levels of p21 and p53. In conclusion, the data indicated that CDK1 was overexpressed in the OIR model and that silencing of CDK1 inhibited angiogenesis in vitro. CDK1 may be a novel therapeutic target for pathological retinal angiogenesis.

Guided by cell-based anti-anaphylactic assay, eighteen cage-like monoterpenoid glycosides ( 1 - 18 ) were obtained from the bioactive fraction of P. lactiflora extract. Among these, compounds 1 , 5 , 6 , 11 , 12 , 15 , and 17 can significantly reduce the release rate of β-HEX and HIS without or with less cytotoxicity. Additionally, the most potent inhibitor benzoylpaeoniflorin ( 5 ) was selected as the prioritized compound for the study of action of mechanism, indicating that its anti-anaphylactic activity was medicated by dual-inhibiting HDC and MAPK signal pathway. Moreover, the molecular docking simulation explained that benzoylpaeoniflorin ( 5 ) could block the conversion of L-histidine to HIS by occupying the HDC active site. Finally, in vivo on PCA using BALB/c mice, benzoylpaeoniflorin ( 5 ) can suppress the IgE-mediated PCA reaction in antigen-challenged mice. These findings indicate that cage-like monoterpenoid glycosides, especially benzoylpaeoniflorin ( 5 ), mainly contributed to the anti-anaphylactic activity of P. lactiflora by dual-inhibiting HDC and MAPK signal pathway. Therefore, benzoylpaeoniflorin ( 5 ) may be considered as a novel drug candidate for the treatment of anaphylactic diseases.

Here we represented the heteropoly acids (HPAs) and polyoxometalate (POM)-based ionic liquids (ILs) catalyzed the effective alcoholysis of furfural alcohol (FAL) to alkyl levulinate. H5AlW12O40 exhibited the highest catalytic activity among HPAs, furnishing > 99 % FAL conversion and 80 % yield of butyl levulinate (BL). The incorporation of IL framework containing sulfate group into HPAs resulted in the enhanced catalytic performance. [MIMBS]5[AlW12O40] achieved the highest BL yield of 94 % and maintained a good catalytic activity after 6 times of recycle and reuse experiments. The effect of the Hammett acidity and structure of catalyst on the catalytic performance of HPAs and POM-based ILs was also investigated.

AIM: To investigate the effect of gold nanoparticles on retinal angiogenesis in vitro and in vivo, and to reveal the possible mechanism. METHODS: Seed growth method was used to synthesize gold nanoparticles (GNPs). The size, zeta potential, absorption spectrum and morphology of GNPs were identified using Malvern Nano-ZS, multimode reader (BioTek synergy2) and transmission electron microscope. Cell viability was analyzed using cell counting kit-8 method and cell growth was assessed with EdU kit. Transwell chamber was used to investigate cell migration. Tube formation method was used to assess the angiogenic property in vitro. Oxygen induced retinopathy (OIR) model was used to investigate the effect of GNPs on retinal angiogenesis. Confocal microscope and Western blot were used to study the possible mechanism of GNPs inhibited angiogenesis. RESULTS: The GNPs synthesized were uniform and well dispersed. GNPs of 10 μg/mL and 20 μg/mL were able to inhibit human umbilical vein endothelial cells proliferation (50% and 72% separately, P

A rapid, sensitive and selective method based on high-performance liquid chromatography coupled with Q-Exactive mass spectrometry was developed and validated for simultaneous quantification of thirteen components in rat plasma, including chlorogenic acid, 5-caffeoylquinic acid, 4-caffeoylquinic acid, luteoloside, isochlorogenic acid A, B and C, scutellarin, baicalin, wogonin, baicalein, phillyrin and forsythoside A. After precipitating proteins from the plasma samples with methanol, chromatographic separation of the thirteen components was achieved by using an XBridge™ C18 column (2.1mm×150mm, 5μm) with the mobile phase consisting of methanol and 0.1% formic acid in water at a flow rate of 0.3mL/min. High-resolution MS quantification was adopted with detection on a Q-Exactive mass spectrometer in full-scan mode, and the results were obtained using a mass extraction window of 10ppm at a mass resolution of 70, 000. All the calibration curves exhibited good linearity (r2>0.991) over the measured ranges. The lower limit of quantitation (LLOQ) was in the range of 1.05-8.13ng/mL. The intra- and inter-day precision (RSD) was less than 11.70% and the accuracy (RE) ranged from -5.58% to 12.29%. No significant matrix effect was observed and the extraction recoveries of all the analytes were more than 79.36%. The developed method was applied to a pharmacokinetic study of the thirteen ingredients in rats after intravenous administration of Tanreqing at three doses of 3, 6 and 12mL/kg. The results indicated that 8 of the 13 components, isochlorogenic acid A, B and C, chlorogenic acid, baicalin, wogonin, luteoloside and forsythoside A, had linear pharmacokinetic properties in the tested dosage range.

The complex resistivity dispersion experiment of the soil with different water content and different chromic salt content is the base of the complex resistivity detection method which will be used for evaluating the field polluted by chromium residue. By the soil complex resistivity dispersion properties experiment in kinds of conditions, we find that complex resistivity amplitude, phase, in-phase resistivity and out-phase resistivity can be influenced by the water content and contamination content; but the complex phase and out-phase resistivity have the obvious dispersion properties. The experiment result shows that the complex resistivity detection technology based on soil dispersion properties can be used to evaluate the field polluted by chromium residue.

The general impact of extra nitrogen on ecological stoichiometry was examined in alpine grasslands on the Tibetan Plateau. Extra nitrogen increased the ratio of nitrogen to phosphorus (N:P ratio) in leaves and aboveground parts of plants by 43.4% and 32.7%, respectively. In contrast, extra nitrogen reduced the ratio of carbon to nitrogen (C:N ratio) in leaves by 30.6%. Extra nitrogen decreased soil C:N ratio by 9.1% in alpine meadows, but increased soil C:N ratio by 3.4% in alpine steppes. Extra urea had a stronger positive impact on aboveground vegetation N:P ratio than did extra ammonium nitrate. Extra urea rather than ammonium nitrate decreased aboveground vegetation C:N ratio and soil C:N ratio. The impact of extra nitrogen on aboveground vegetation N:P ratio was positively correlated with latitude, mean annual temperature and precipitation, nitrogen application rate and accumulated amount, but negatively correlated with elevation, duration and aboveground vegetation N:P ratio of the control plots. The impact of extra nitrogen on leaves N:P ratio was positively correlated with nitrogen application rate and accumulated amount. The impact of extra nitrogen on leaves C:N ratio was positively correlated with latitude, but negatively correlated with mean annual temperature and precipitation, nitrogen application rate, accumulated amount, duration and leaves C:N ratio of the control plots. Therefore, nitrogen enrichment caused by human activities will most likely alter element balance and alpine plants from nitrogen limitation to phosphorus limitation. This effect may weaken with time, and increase with climatic warming, increased precipitation and nitrogen input rate.

Optically pure tetrahydroquinolines are efficiently synthesized by the Mannich—Michael cascade process in the presence of an indan amine-thiourea catalyst.

Glial cell line-derived neurotrophic factor (GDNF) promotes the survival and functions of neurons. It has been shown to be a promising candidate in the treatment of ischemia and other neurodegenerative diseases. We transfected mouse astrocytes in primary cultures with a human GDNF gene and found that their conditioned medium could not only support the growth and survival of cultured dopaminergic neurons but also protect astrocytes from staurosporine- and ischemia-induced apoptosis. This indicated that these transfected astrocytes could release GDNF. A similar protective effect on astrocytes against apoptosis was evident when recombinant human GDNF was used. Moreover, GDNF reduced caspase-3 activity but not that of caspase-1 in cultured astrocytes after ischemia treatment. Thus, GDNF protects astrocytes from apoptosis by inhibiting the activation of caspase-3.

The kesterite compound Cu2ZnSnS4(CZTS) is one of the most interesting materials for absorber layers of thin-film solar cells,not only because it is composed of earth abundant and non-toxic elements,but also owing to the fact that its absorption coefficient is high (on the order of 104 cm-1) and its optimal band gap is 1.5 eV for single-junction solar cells. Plenty of methods are used to deposit the CZTS layer,such as evaporation,sputtering,spray-pyrolysis,sol-gel, pulsed laser deposition and electro-chemical deposition.Among these methods,sputtering is considered as one of the most viable deposition techniques for producing a large-scale panel of thin film solar cells with demonstrable productivity and easy adjustment.In this paper,Cu2ZnSnS4 thin films are prepared by in-situ annealing after being sputtered with a quaternary compound target.This technology can reduce the extrinsic defects in the thin film.It is desirable to control the growth of grain boundary,increase grain size and make the thin film more compact and smooth. The in-situ annealing is a method which can heat a work piece fast to a certain temperature and maintain the temperature for some time after sputtering.As is well known,one of the major reasons for affecting CZTS device performance is the low open circuit voltage (Voc),and it is also a challenge to obtain a high value because there are a lot of defect states at the grain boundaries.The experiment shows that using the method of in-situ annealing after sputtering can obtain large size grains and smooth and compact surface.The obtained thin films are Cu-poor,Zn-rich and Sn-poor,which can restrain the Cu vacancies (VCu) and anti-site defects (CuZn,SnZn,and SnCu).The free carrier concentration (NA) increases with the increase of Zn content,while the open circuit voltage of CZTS solar cells increases with the increase of NA. In order to develop CZTS solar cells based on the thin films,the n-type CdS buffer layer (70 nm) is grown using chemical bath deposition,and intrinsic ZnO (70 nm) and ZnO:Al (250 nm) films are deposited by RF-magnetron sputtering.In the end,Ni-Al metal grids as the top electrode are prepared by thermal evaporation.The final solar cells with an active area of 0.25 cm2 are determined by mechanical scribing.The solar cell based the CZTS film with in-situ annealing has better-performance parameters,its open circuit voltage and short-circuit current density are 575 mV and 8.32 mA/cm2,respectively.The photoelectric conversion efficiency of 1.82% is achieved.In order to enhance the efficiency of device,it is important to minimize Cu/Zn disorder in CZTS film and control the element composition by optimizing high-temperature crystallization process.The relevant research work on reducing defects in the films,increasing the carrier collection and enhancing the Jsc is under way. This method not only avoids the contamination caused by the external annealing but also simplifies the preparation process of the thin film,which greatly saves the preparation time of the solar cell and is beneficial to industrial production.annealing is a method which can heat a work piece fast to a certain temperature and maintain the temperature for some time after sputtering.As is well known,one of the major reasons for affecting CZTS device performance is the low open circuit voltage (Voc),and it is also a challenge to obtain a high value because there are a lot of defect states at the grain boundaries.The experiment shows that using the method of in-situ annealing after sputtering can obtain large size grains and smooth and compact surface.The obtained thin films are Cu-poor,Zn-rich and Sn-poor,which can restrain the Cu vacancies (VCu) and anti-site defects (CuZn,SnZn,and SnCu).The free carrier concentration (NA) increases with the increase of Zn content,while the open circuit voltage of CZTS solar cells increases with the increase of NA. In order to develop CZTS solar cells based on the thin films,the n-type CdS buffer layer (70 nm) is grown using chemical bath deposition,and intrinsic ZnO (70 nm) and ZnO:Al (250 nm) films are deposited by RF-magnetron sputtering.In the end,Ni-Al metal grids as the top electrode are prepared by thermal evaporation.The final solar cells with an active area of 0.25 cm2 are determined by mechanical scribing.The solar cell based the CZTS film with in-situ annealing has better-performance parameters,its open circuit voltage and short-circuit current density are 575 mV and 8.32 mA/cm2,respectively.The photoelectric conversion efficiency of 1.82% is achieved.In order to enhance the efficiency of device,it is important to minimize Cu/Zn disorder in CZTS film and control the element composition by optimizing high-temperature crystallization process.The relevant research work on reducing defects in the films,increasing the carrier collection and enhancing the Jsc is under way. This method not only avoids the contamination caused by the external annealing but also simplifies the preparation process of the thin film,which greatly saves the preparation time of the solar cell and is beneficial to industrial production.

Optically pure tetrahydroquinolines are efficiently synthesized by the Mannich—Michael cascade process in the presence of an indan amine-thiourea catalyst.

According to the determining results of total phosphorus for the A/A/O all-process of a wastewater treatment plant of Beijing in China, it were analyzed for the phosphorus balance of the system and the denitrifying phosphorus removal of the anoxic phase. And it was discussed for the correlation between the phosphorus removal and process operating parameters. Then the optimal parameters of A/A/O process control were proposed based on the phosphorus removal. The main conclusions were as follows: The phosphorus removal of anoxic phase and oxic phase were 4.97mg/L and 5.5mg/L separately, which there was the obvious denitrifying phosphorus removal in anoxic phase. On the whole, the phosphorus load of the influent and effluent in the process was balance, the total phosphorus removal rate of sewage was about 78∼94%. There was a negative correlation relation between phosphorus removal rate and sludge retention time. The larger excess activated sludge discharge, the lower phosphorus accumulation in the A/A/O process system. The appropriate sludge discharge of the process should be remained at 4000∼5000m3 per day. The phosphorus load proportion of influent accounted for 98 percent of entering into the process system, the rest came from the waste liquor of sludge treatment process in the wastewater treatment plant. In the discharge phosphorus load of the treatment plant, dewatered sludge cake had taken out 84 percent, effluent accounted for 14 percent, and the waste liquor of sludge treatment process was only 2 percent.

A new multisignaling molecular probe DFDB was designed for the selective detection of Zn(2+). DFDB can be synthesized by a simple one-step reaction in high yield. Theoretical calculation suggests a novel sandwich structure of the DFDB·Zn(2+) complex.

In this paper, an a-Si/Ge thin film with a buried layer of Ge and an a-Si thin film are prepared on Si substrates at a temperature of 500 ℃ by magnetron sputtering. The prepared films are annealed for 5h at different temperatures in vacuum. The annealed films are characterized by Raman scattering, X-ray diffraction, atomic force microscope and field emission scanning electron microscope. The results reveal that Ge can induce amorphous Si (a-Si) growing at a temperature of 500 ℃ by magnetron sputtering crystallize after annealing at a temperature of 600 ℃ for 5h. And in the a-Si/Ge thin film the degrees of crystallization of a-Si are 44% and 54% at the annealing temperatures of 600 ℃ and 700 ℃, respectively. By comparison, a-Si thin film without Ge is crystallized at an annealing temperature of 800 ℃ for 5h and the degree of crystallization is 46%. The crystallization temperature of a-Si/Ge is reduced by 200 ℃ compared with that of a-Si film without buried Ge layer in the film. The prepared poly-Si thin film possesses high Si(200) orientation with a grain size of 76 nm. The preparation of poly-Si film by Ge-induced crystallization might be a useful technology for developing high-quality poly-Si film.