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A new, efficient approach toward the preparation of 2-aryl-2,3-dihydrobenzofuran scaffolds through the Cu/SPDO-catalyzed [3 + 2] cycloaddition between quinone ester and styrene derivatives has been developed. The procedure features excellent enantioselectivities (up to 99% ee), high yields (up to 96%), and broad substrate tolerance. Additionally, asymmetric synthesis of natural corsifurans A and B from commercially available starting materials has also been achieved in two or three steps using this reaction as a key transformation.

A novel spiro-pyrrolidine (SPD)-derived bifunctional thiourea catalyst has been developed, enabling the development of a stereoselective conjugate addition of furfurals to β,γ-unsaturated α-ketoesters. The reaction represents an example of asymmetric trienamine catalysis in the benzylic C–H functionalization of 5-benzylfurfurals, and the rigid spirocyclic framework of the catalyst is proven to be essential for a highly enantioselective transformation.

Two main problems in partial nitrification at low temperature are its difficult start-up and easy inhibition, and this issue significantly limits the broad application of advanced partial nitrification technology. To promote rapid culturing and stabilization of partial nitrification biofilms, two experiments were carried out to investigate the influence of C/N on partial nitrification through ratio control (R, dissolved oxygen (DO)/effluent total ammonia nitrogen (TANeff)) in a lab-scale moving bed biofilm reactor (MBBR) at 12 °C. One experiment looked at the effect of C/N on the stable operation of partial nitrification at 12 °C, which inoculated a mature biofilm with good partial nitrification performance; the other looked at the effect of C/N on the biofilm cultivation and start-up of partial nitrification at 12 °C, which inoculated activated sludge and Pall rings. As for the startup experiments, only the C/N ratio was investigated, as the DO/TANeff ratio was kept constant. The effect of C/N on the mature partial nitrification biofilm showed that the increase of C/N could increase the resistance of partial nitrification to high DO. The nitrite accumulation ratio (NAR, (NO2−-N/(NO2−-N + NO3−-N) × 100%)) increased from 40.41% to 98.78% when R was 0.25 and C/N increased from 0 to 1. Meanwhile, when C/N increased to 2 and the R value slightly increased to 0.3, partial nitrification failed. The penetration of DO in the biofilm indicated that the increase of C/N enhanced the mass transfer resistance of DO, but it was similar when C/N was 1 and 2. Adding an appropriate amount of C/N can reduce the negative effect of partial nitrification damage caused by DO/TAN enlargement. The start-up experiment showed that C/N = 1 and C/N = 2 were essential for culturing biofilms and achieving partial nitrification at 12 °C, which can be successfully achieved (NAR was 85% and 96%) on the 56th and 52nd days. Neither C/N = 0 nor C/N = 3 could effectively achieve the partial nitrification. The increase of C/N will reduce the proportion of nitrifying bacteria in the biofilm, which is harmful to the partial nitrification. This will also lead to the decrease of protein/polysaccharide (PN/PS) and affect the stability of the biofilm.

Background: The hemoglobin glycation index (HGI) has been proposed as a marker to quantify inter-individual variation in hemoglobin glycosylation. However, whether HGI is associated with an increased risk of diabetic complications independent of glycated hemoglobin (HbA1c) remains unclear. This meta-analysis aimed to determine the association between HGI and the risk of all cause mortality and composite cardiovascular disease (CVD).Methods: PubMed, and EMBASE databases were searched for related studies up to March 31, 2021. Observational studies reported associations between HGI levels and composite CVD and all cause mortality were included for meta-analysis. A random effect model was used to calculate the hazard ratios (HRs) and 95% confidence intervals (CI) for higher HGI.Results: A total of five studies, comprising 22,035 patients with type two diabetes mellitus were included for analysis. The median follow-up duration was 5.0 years. After adjusted for multiple conventional cardiovascular risk factors, an increased level of HGI was associated with a higher risk of composite CVD (per 1 SD increment: HR = 1.14, 95% CI = 1.04–1.26) and all cause mortality (per 1 SD increment: HR = 1.18, 95% CI = 1.05–1.32). However, when further adjusted for HbA1c, the association between HGI and risk of composite CVD (per 1 SD increment of HGI: HR = 1.01, 95% CI = 0.93–1.10) and all cause mortality (per 1 SD increment of HGI: HR = 1.03, 95% CI = 0.96–1.10) became insignificant.Conclusions: High HGI was associated with an increased risk of composite CVD and all cause mortality after adjustment for multiple conventional cardiovascular risk factors. However, the association was mainly mediating by the level of HbA1c.

The effect of the novel composite material LiNbO3@Fe3O4 on the nitrate removal, and Mn2+ oxidation efficiency by autotrophic denitrification strain Achromobacter sp. A14 was investigated in this st...

A novel Fe3O4@Cu/PVA biomaterial as a new adsorbent and bacterial cell immobilized carrier was synthesized in this work. The structure and morphology were characterized by scanning electron microscopy (SEM). Effects of factors on Mn(II)-based autotrophic denitrification were investigated in a moving bed biofilm reactor (MBBR). The results indicate that the highest nitrate removal and Mn(II) oxidation efficiency occurred under the conditions of initial Mn(II) concentration of 80 mg·L−1, hydraulic retention time (HRT) of 10 h and pH 7. Meteorological chromatography analysis showed that N2 was produced as an end-product, and that gas compositions were different depending on the concentration of Mn(II) in the MBBR. The community diversity in the MBBR was markedly influenced by the concentration of Mn(II) and Pseudomonas sp. H-117 played a primary role in the process of nitrate removal and Mn(II) oxidation.

Designing versatile materials for radiation protection is of great significance to the rapid development of nuclear technology. Here, BN@PbWO4 core-shell particles are successfully prepared via a facile sol-gel method. The structure and morphology of products are determined by XRD, SEM, TEM and FTIR techniques. Compared with PbWO4 and h-BN, BN@PbWO4 exhibits much more excellent photocatalytic ability to degrade the organic dye Rhodamine B (RhB). Furthermore, it also has a good ability to jointly shield neutron and gamma radiations, especially better gamma radiation shielding in comparison with PbWO4. This work provides an integrated solution with the material that could deal with organic wastes and shield complex radiations in nuclear industry.

Background Sepsis is a severe condition characterised by the body’s systemic inflammatory response to infection. The specific sepsis-related biomarkers should be used in clinical diagnosis, therapeutic response monitoring, rational use of antibiotics, and prognosis (risk stratification), etc. Results In this study, we investigated the expression level of Decoy Receptor 3 (DcR3) and the mechanism of high expression in sepsis patients. Septic cell model experiments were performed by treating human umbilical vein endothelial cells (HUVECs) and Jurkat cells with lipopolysaccharide (LPS), lipoteichoic acid (LTA) and zymosan, respectively. SP600125, SB203580 and ammonium pyrrolidinedithiocarbamate (PDTC) were used to inhibit JNK1/2, p38MAPK and NF-κB signalling pathways in septic cell model, respectively. These results showed that DcR3 levels were higher in sepsis group than control. DcR3 mRNA and protein levels in HUVECs were increased following treatment with LPS, LTA and zymosan, and also increased in Jurkat cells treated by LPS, but not by LTA or zymosan. When HUVECs were treated with the NF-κB inhibitor PDTC, DcR3 expression was decreased compared with controls. However, SP600125 and SB203580 had no effect on DcR3 mRNA or protein levels. Conclusions The results indicated that DcR3 secretion proceeded through the NF-κB signalling pathway in HUVECs.

Sulfur(vi) fluoride exchange (SuFEx) is a category of click chemistry that enables covalent linking of modular units through sulfur(vi) connective hubs. The efficiency of SuFEx and the stability of the resulting bonds have led to polymer chemistry applications. Now, we report the SuFEx click chemistry synthesis of several structurally diverse SOF4-derived copolymers based on the polymerization of bis(iminosulfur oxydifluorides) and bis(aryl silyl ethers). This polymer class presents two key characteristics. First, the [–N=S(=O)F–O–] polymer backbone linkages are themselves SuFExable and undergo precise SuFEx-based post-modification with phenols or amines to yield branched functional polymers. Second, studies of individual polymer chains of several of these new materials indicate helical polymer structures. The robust nature of SuFEx click chemistry offers the potential for post-polymerization modification, enabling the synthesis of materials with control over composition and conformation. Sulfur(vi) fluoride exchange (SuFEx)—a type of click chemistry that generates SVI-centred covalent linkages—has previously been used for polymer synthesis. Now, modular SuFEx polymerization using SOF4 has been used to generate helical polymers. Unlike previous examples of SuFEx polymerization, the backbone retains SVI–F motifs and therefore is able to undergo further SuFEx click reactions, enabling facile and efficient post-polymerization modification.

Objectives This study aimed to investigate the factors affecting the quantity of DNA and RNA extractable from human formalin-fixed paraffin-embedded (FFPE) tissues stored for different lengths of time. Methods We randomly selected 20 FFPE specimens harvested from hysteromyoma patients with uterine fibroids during 2010, 2015, and 2017 at the Department of Pathology, Jiading District Central Hospital Affiliated Shanghai University of Medicine and Health Sciences. DNA and RNA extractions were performed using a DNA/RNA FFPE kit. DNA and RNA concentrations and their OD260/OD280 ratios were determined by a NanoDrop 2000 spectrophotometer. The human β-globin gene and aldehyde dehydrogenase-2 (ALDH2) gene were amplified from nucleic acids using a LightCycler 480 Real-Time PCR System, and PCR amplification products were electrophoresed on 1% agarose gels. Results Specimens that were stored for longer showed more degradation and a reduced concentration of DNA and RNA after nucleic acid extraction. However, there was no significant difference in DNA or RNA purity. β-globin and ALDH2 genes could be amplified from more than 99% of specimens. Conclusion We found that FFPE tissues stored for longer had a reduced quantity of extractable DNA and RNA. However, these tissues could be used for the analysis of some small target genes.

Objectives The purpose of this paper was to synthesize 4-amino-1,2,4-triazole Schiff base derivative and to evaluate its antitumor activity. Methods 2,4,6-Tris (4-formylphenoxy)-1,3,5-triazine was synthesized by nucleophilic substitution with reaction of p -hydroxybenzaldehyde with cyanuric chloride. Then, the intermediate was reacted with 1,2,4-triazole to form 4-amino-1,2,4-triazole Schiff base derivative by reduction and ammonification of aldehydes. The 4-amino-1,2,4-triazole Schiff base derivative was characterized by infrared spectroscopy, nuclear magnetic resonance, and elemental analyses. Finally, the anticancer effect of 4-amino-1,2,4-triazole Schiff base derivative was evaluated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay on a lung adenocarcinoma cell line (A549) and a human hepatoma cell line (Bel7402). Results The product synthesized in this study was confirmed to be 4-amino-1,2,4-triazole Schiff base derivative, and it significantly suppressed the proliferation of cancer cell lines in a dose-dependent manner. Conclusions We successfully prepared 4-amino-1,2,4-triazole Schiff base derivative and verified its antitumor activity.

SuFEx reactions, in which an S−F moiety reacts with a silyl‐protected phenol, have been developed as powerful click reactions. In the current paper we open up the potential of SuFEx reactions as enantioselective reactions, analyze the role of Si and outline the mechanism of this reaction. As a result, fast, high‐yielding, “Si‐free” and enantiospecific SuFEx reactions of sulfonimidoyl fluorides have been developed, and their mechanism shown, by both experimental and theoretical methods, to yield chiral products., The SuFEx reaction is shown to proceed quantitatively and fast with wide scope without silyl protection of the phenol. Mechanistic studies reveal a stereospecific bimolecular nucleophilic substitution.

Anaerobic ammonia oxidation (anammox) and denitrification can work together to weaken the influence of organic matter on anaerobic ammonia oxidation bacteria (AAOB) and improve nitrogen removal performance. As the common substrate of anammox and denitrification, nitrite will also affect nitrogen removal performance when it is insufficient, which is not conducive to reflect the endurance of anammox reactor to organic matter. The UASB continuous flow experiment was carried out to investigate the effect of the concentration of glucose and sodium acetate on nitrogen removal performance of anammox reactor under the condition of sufficient nitrite. With glucose as the organic matter, when the chemical oxygen demand (COD) concentration increased to 200 mg l −1 , nitrogen removal performance of the system began to deteriorate significantly, and the anammox activity was significantly inhibited. With sodium acetate as the organic substance, the anammox activity was affected when the COD was 20 mg l −1 . Adequate nitrite could relieve the inhibition of the coupling system by a low concentration (COD < 200 mg l −1 ) of glucose organic matter. However, it could not relieve the inhibitory effect of sodium acetate. With the increase of organic concentration, the biological density of AAOB in granular sludge gradually decreased, while the biological density of denitrifying bacteria increased gradually.

Membrane scaling is a critical challenge for membrane distillation (MD), especially when treating hypersaline brines. In this study, an anti-scaling membrane was developed with a liquid-like surface coating. This fabrication approach combined electrospun polyvinylidene fluoride (PVDF) membrane with surface fluorination without the addition of nanoparticles. Two fluoro silanes with the same alkyl-chain length but different hydrolysis reaction sites were investigated as the fluorination agents. Membrane characterizations indicated that surface modification with the single hydrolysis site fluoro silane (17-FAS-S) did not change the membrane morphology or structure. On the other hand, surface modification with the triple hydrolysis site fluoro silane (17-FAS-T) generated nanoparticles on the membrane surface, resulting in increased roughness. While both the 17-FAS-S and 17-FAS-T modified membranes exhibited excellent scaling resistance in the MD scaling tests, the 17-FAS-S membrane provided a much higher vapor flux than the 17-FAS-T one. Finally, the mechanism of scaling resistance and vapor permeability provided by the liquid-like modification was discussed.

In this study, strain CC76, identified as Enterobacter sp., was tested for the reduction of Fe3+ and denitrification using immobilized pellets with strain CC76 as experimental group (IP) and immobilized pellets with strain CC76 and magnetite powder as experimental group (IPM) in the autotrophic denitrification immobilized systems (ADIS). Compared with IP, a higher nitrate removal rate was obtained with IPM by using three levels of influent Fe3+ (0, 5, and 10 mg/L), four levels of pH (5.0, 6.0, 7.0, and 8.0), and three levels of hydraulic retention time (HRT) (12, 14, and 16 h), respectively. Furthermore, response surface methodology (RSM) analysis demonstrated that the optimum removal ratios of nitrate of 87.21% (IP) and 96.27% (IPM) were observed under the following conditions: HRT of 12 h, pH of 7.0 and influent Fe3+ concentration of 5 mg/L (IP) and 1 mg/L (IPM).

Harmful algal blooms (HABs) could be deemed hazardous materials in aquatic environments. In this study, we investigated aerobic denitrification and algicidal effects of the Raoultella sp. R11. Based on PCR amplification, the denitrification genes nap A was detected. A response surface methodology (RSM) analysis demonstrated that the maximum nitrate removal ratio was 96.06%, and optimal conditions occurred for inoculum of 13.02% (v/v), initial pH of 6.65, C/N ratio of 7.59 and temperature of 27.08 °C based on a ridge analysis. When the Microcystis aeruginosa flour as carbon and nitrogen source for denitrification in aerobic conditions, the NO 3 − -N and TOC removal ratios were 72.36% and 85.56%, respectively. Additionly, the denitrification rate was 0.0123 mg L −1 h −1 . Furthermore, the infrared spectrogram and SEM images showed the M. aeruginosa cell structure was destroyed, indicating that R11 could use algal death for denitrification. Therefore, Raoultella sp. R11 played a crucial role for simultaneous denitrification and algicidal effects in wastewater treatment.

In this study, immobilization technique was employed to improve simultaneous algicidal and denitrification of immobilized Acinetobacter sp. J25 with magnetic Fe3O4 in eutrophic landscape water. After 7 days of operation, the maximum superoxide dismutase (SOD) activity (54.43 U mg-1), nitrate removal efficiency (100% (0.2127 mg L-1 h-1)), and chlorophyll-a removal efficiency (89.71%) were obtained from the immobilized J25 with magnetic Fe3O4. The results suggest that immobilized J25 with magnetic Fe3O4 had better nitrogen removal efficiency and algicidal activity in eutrophic landscape water. High-throughput sequencing data profiled the strain J25 that was immobilized with magnetic Fe3O4 which changed the composition of the microbial community. The results indicated a novel concept of enhancing the algicidal and denitrification property of immobilized bacteria with magnetic Fe3O4 in eutrophic landscape water.

An immobilized biological filter (IBF) using Fe(II) and Mn(II) as mixed electron donors was evaluated for nitrate removal in groundwater. Results of the single factor experiments of strain SZ28 under the conditions of electron donor:electron acceptor ratio (1:2, 1.45:1, 3:1), Fe(II):Mn(II) ratio (1:9, 3:7, 5:5) demonstrated that the highest nitrate removal ratio was 100%, 49.6% (Mn(II)) and 100% (Fe(II)) under the conditions of electron donor:electron acceptor ratio of 3:1, Fe(II):Mn(II) ratio of 5:5. Mn(II) and Fe(II) as electron donor was tested for the effects on denitrification in the IBF reactor. Optimal conditions were obtained at an electron donor:electron acceptor ratio of 2:1, hydraulic retention time of 12 h and Fe(II):Mn(II) ratio of 5:5 with the highest removal ratio of nitrate-N (100%), Mn(II) (50.25%) and Fe(II) (99.2%). Results suggest that the optimal condition obtained from the IBF was feasible.

Presented in this paper are the practical synthesis and conformational structure of hydrazo-bridged homo calix[4]arenes. The step-wise fragment coupling method based on the nucleophilic aromatic substitution reaction of 2,6-dihydrazinylpyridine with 6-alkoxy-2,4-dichlorotriazine afforded effectively hydrazo-linked homo calix[2]pyridine[3]triazines. The exhaustive methylation of –NHNH– linkages led to lipophilic macrocycles, while the introduction of a THP-protected triglyme moiety on a triazine ring produced a water soluble hydrazo-bridged homo calix[2]pyridine[2]triazine. The acquired hydrazo-bridged homo calix[4]arenes adopted a cone conformational structure with two nitrogen atoms of the hydrazine linkage forming respectively a conjugation system with pyridine and triazine rings. The unique macrocyclic conformation and multidentate binding sites would render hydrazo-bridged homo calix[2]pyridine[2]triazines powerful hosts in molecular recognition and self-assembly.

A possible correlation between liver cancer pain and the hypoxia-inducible factor (HIF)-1 and vascular endothelial growth factor (VEGF) expression levels was examined. From January, 2015 to January, 2016, 30 patients suffering from liver cancer with pain, 30 patients with liver cancer without pain and 30 hepatitis patients with pain were enrolled in the study. Pain level was evaluated by visual analogue scale (VAS), the expression levels of HIF-1 and VEGF mRNA were determined by RT-PCR and the expression levels of HIF-1 and VEGF proteins were examined by ELISA. Before intervention, the VAS in the hepatitis group was significantly higher than that of the liver cancer pain group. However, after intervention the VAS in the two groups was reduced. HIF-1 and VEGF mRNA expression levels in the liver cancer pain group were significantly higher than those in the liver cancer group before and after intervention. The expression levels of HIF-1 and VEGF mRNA in the hepatitis group were the lowest. The expression levels of HIF-1 and VEGF mRNA in the liver cancer pain group considerably increased after intervention. The expression levels of HIF-1 and VEGF mRNA in the other two groups showed no changes before or after intervention. Before and after the intervention, VAS in the liver cancer pain group was positively correlated to the expression levels of HIF-1 and VEGF. Thus, pain occurrence and the pain level in liver cancer patients were correlated with the expression levels of HIF-1 and VEGF. As the regular three-step medicine analgesic ladder is ineffective in these cases, verification of HIF-1 and VEGF expression levels may be considered the new target for pain release.

This study investigated sulfamethoxazole (SMX) biodegradation and nitrogen conversion by Achromobacter sp. JL9 using different carbon and nitrogen sources. Results showed that SMX and sodium acetate could be co-metabolized as carbon sources for bacterial growth and nitrogen conversion with highest removal efficiencies of 82.44%, 80.2%, and 79.45% for NH4+-N, NO3--N, and SMX, respectively. Strain JL9 was able to utilize SMX as its sole nitrogen source for growth, with an SMX biodegradation efficiency of 63.10%. In addition, carbon and nitrogen balance analyses showed that approximately 35.31% and 63.22% of carbon and nitrogen, respectively, were lost as gaseous products. Finally, medium toxicity gradually decreased during the carbon and nitrogen dependence experiments. This study, thus, suggests that carbon and nitrogen play vital roles in SMX biodegradation and biotoxicity reduction.

An immobilized biofilm reactor (IBR) was established to treat nitrate using different electron donors. A novel material, Fe3O4@Cu/PVA, was synthesized as an adsorbent and bacterial immobilized carrier in the reactor. The optimum condition of nitrate removal were pH 7.0, hydraulic retention time (HRT) of 10 h under autotrophic and mixotrophic conditions. Strain H-117 in the mixotrophic reactor had better adaptability to changes in the initial pH. The metabolism in the mixotrophic reactor was more vigorous than that in autotrophic reactor. The microbial communities and structures were evaluated to determine the nitrate removal mechanisms in this system. Microbial analyses demonstrated that different electron donor could influence the bacterial abundance and species in the IBR system. Proteobacteria was the most dominant phylum in all IBRs and accounted for more than 50% of the total phyla. Pseudomonas and Rhizobium were the dominant contributor to the effective removal of nitrate in the IBRs.

A practical synthetic method has been developed for polyfunctionalized biaryls based on a facile one-pot nucleophilic aromatic substitution (SNAr) reaction and [5,5]- or [3,3]-sigmatropic rearrangement reaction cascade. Under mild basic conditions, N-arylhydroxylamines reacted with o-activated fluoro (het)arenes to form N,O-diarylhydroxylamine intermediates which underwent spontaneously selective [5,5]-sigmatropic rearrangement reaction to produce diverse functionalized 4-amino-4′-hydroxy-1,1′-biaryls. A sequential SNAr reaction and [3,3]-sigmatropic rearrangement took place between N-arylhydroxylamines and 2-fluoropyridine derivatives or 4-fluorobenzonitrile to afford functionalized 2-amino-2′-hydroxy-1,1′-biaryls. As invaluable and unique building blocks, the resulting biaryls were applied in the straightforward synthesis of N2,O2-coronarene, carbazole, aza- and diaza carbazole derivatives.

The urotensin II/urotensin receptor (UII/UT) system can mediate inflammatory liver injury in acute liver failure (ALF); however; the related mechanism is not clear. In this study, we confirmed that lipopolysaccharide/D-galactosamine (LPS/D-GalN) induced up-regulation of liver interferon regulatory factor 3 (IRF3) in ALF mice, whereas the UT antagonist urantide inhibited the up-regulated liver IRF3. LPS stimulation induced IRF3 transcription and nuclear translocation and promoted the secretion of interleukin-6 (IL-6), interferon (IFN)-β, and IFN-γ in Kupffer cells (KCs); these effects in LPS-stimulated KCs were inhibited by urantide. Knockdown of IRF3 using an adenovirus expressing an IRF3 shRNA inhibited IFN-β transcription and secretion as well as tumor necrosis factor (TNF)-α and IL-1β secretion from LPS-stimulated KCs; additionally, IL-10 transcription and secretion were promoted in response to LPS. However, LPS-stimulated TNF-α and IL-1β mRNA was not affected in the KCs. The IRF3 shRNA also did not have a significant effect on the NF-κB p65 subunit and p38MAPK protein phosphorylation levels in the nuclei of LPS-stimulated KCs. Therefore, IRF3 expression and activation depended on the signal transduction of the UII/UT system, and played important roles in UII/UT-mediated immune inflammatory injury in the liver but did not affect NF-κB and p38 MAPK activity.

In this study, zero-valent iron (ZVI), nanoscale zero-valent iron (nZVI), Fe(II), and Mn(II) were investigated for their effects on mixotrophic denitrification coupled with cadmium (Cd(II)) adsorption process by Acinetobacter sp. SZ28. The removal rates of nitrate were 0.228 mg L−1 h−1 (ZVI), 0.133 mg L−1 h−1 (nZVI), 0.309 mg L−1 h−1 (Fe(II)) and 0.234 mg L−1 h−1 (Mn(II)), respectively. The Cd(II) removal efficiencies were 97.23% (ZVI), 95.79% (nZVI), 80.63% (Fe(II)), and 84.58% (Mn(II)), respectively. Meteorological chromatography analysis indicated that the characteristics of gas composition were different under different electron donor conditions. Moreover, characterization of bacterial metabolites produced by strain SZ28 under different conditions was analyzed. Sequence amplification identified the presence of the nitrate reductase gene (napA) and Mn(II)-oxide gene (cumA) in strain SZ28. The results of XRD and SEM indicated that ZVI, nZVI, Fe(II), and Mn(II) were oxidized into corresponding oxides. XPS spectra indicated that the Cd(II) was adsorbed onto biogenic precipitation.

Background HOXB9 is a homeobox transcription factor which plays an important role in carcinoma development. This protein has been shown to inhibit cancer cell proliferation. However, the mechanisms that underpin HOXB9-mediated inhibition of cellular proliferation remain to be elucidated. Methods In this study, two gastric cancer cell lines, SGC7901 and MKN45, were transfected with plasmids pLVX-HOXB9 and shHOXB9. These transfections resulted in the over-expression of the HOXB9 gene in the SGC7901/HOXB9 cells and knockdown of the HOXB9 gene in the MKN45/shHOXB9 cells. Results Over-expression of the HOXB9 gene in the SGC7901/HOXB9 cells caused an increase in the apoptotic rate and a concomitant reduction in metastatic ability compared with the knocked-down MKN45/shHOXB9 cells. Moreover, a reduction in the expression of the phosphorylated-Akt protein was observed in the SGC7901/HOXB9 cells, while an increase in expression of the same protein was observed in the MKN45/shHOXB9 cells. We also observed that HOXB9 mediated a reduction in both NF-κB and N-cadherin and Snail protein expression. Conversely, HOXB9 caused an increase in the expression of E-cadherin. Conclusions In summary, this study reports that HOXB9 can suppress both phosphorylated-Akt expression and NF-κB activity. The latter phenomenon affects Snail protein expression and the inhibition of gastric carcinoma proliferation.

PepT1 can transport bacterial oligopeptide products and induce intestinal inflammation. Our aim was to investigate the mechanism of the small intestine injury induced by bacterial oligopeptide product muramyl dipeptide (MDP) which is transported by PepT1. We perfused the jejunum with a solution with or without MDP, or with a solution of MDP + Gly-Gly and explored the degree of inflammation to determine the role of PepT1–Nod2 signaling pathway in small intestine mucosa. MDP perfusion induced inflammatory cell accumulation and intestinal damage, accompanied by an increase in mucosal Nod2 and Rip2 transcript expression. NFκB activity and inflammatory cytokine expression, including serum levels of TNF-α, IL-1β, and IL-6, increased in the MDP group compared to the controls; these effects were reversed by perfusion of the nutritional dipeptide Gly-Gly. MDP can be transported through PepT1, causing inflammatory damage in the rat small intestine. Nod2–Rip2–NFκB signaling involved in the small intestinal inflammatory injury caused by MDP which is transported through PepT1.

Lanostane-type triterpenoids, inotolactones A and B, a drimane-type sesquiterpenoid, inotolactone C, and five known terpenoids 6β-hydroxy-trans-dihydroconfertifolin, inotodiol, 3β,22-dihydroxyanosta-7,9(11),24-triene, 3β-hydroxycinnamolide, and 17-hydroxy-ent-atisan-19-oic acid, were isolated from the submerged culture of chaga mushroom, Inonotus obliquus. Their structures were characterized by spectroscopic methods, including MS and NMR (1D and 2D) spectroscopic techniques. Inotolactones A and B, examples of lanostane-type triterpenoids bearing α,β-dimethyl, α,β-unsaturated δ-lactone side chains, exhibited more potent alpha-glucosidase inhibitory activities than the positive control acarbose. This finding might be related to the anti-hyperglycemic properties of the fungus and to its popular role as a diabetes treatment. In addition, a drimane-type sesquiterpenoid and an atisane-type diterpenoid were isolated from I. obliquus.

A novel optical rhodamine–quinoline type chemosensor (REQ) was successfully synthesized and characterized as a reversible molecular switch. It displayed high selectivity toward Al3+ among 19 metal ions and the resultant complex [REQ–Al3+] acted as a sequential chemosensor toward F− among 16 anions in neutral aqueous media (ethanol–water, v/v = 3/7, Tris–HNO3, 20 mM, pH 7.0). Moreover, detecting fluoride at concentrations below the maximum contaminant level in drinking water defined by the U. S. Environmental Protection Agency (4.0 mg L−1, 211 μM) could be achieved with a detection limit (LOD) estimated to be down to 8.0 μM. The reversible ring-open mechanism of the rhodamine spirolactam induced by Al3+ binding and the 1 : 1 stoichiometric structure between REQ and Al3+ were adequately supported by Job plot evaluation, optical titration, and 1H NMR study. Finally, it could be conveniently used for the determination of Al3+ and F− with the “naked eye” due to the obvious color change of the testing solution, showing its potential practical application.

A novel optical Rhodamine-Furan type chemosensor (RF) was easily synthesized and characterized as a revisable switch. It dispalyed high selectivity toward Al 3+ among 19 metal ions and the resultant complex [RF–Al 3+ ] as a sequential chemosensor toward F − among 16 anions in neutral aqueous media (ethanol/water, v/v = 2/3, Tris–HNO 3 , 10 mM, pH 7.0). Moreover, detecting fluoride at concentration below the maximum contaminant level in drinking water defined by the U.S. Environmental Protection Agency (4.0 mg L −1 , 211 μM) could be achieved with a detection limit (LOD) estimated down to 1.6 μM. Both sensors were very easily to construct and only required simple synthesis. The reversible ring-open mechanism of the rhodamine spirolactam induced by Al 3+ binding and the 1:1 stoichiometric structure between RF and Al 3+ were adequately supported by job plot evaluation, optical titration, and 1 H NMR study. Finally, it could be conveniently used for the determination of fluorides in dental products such as toothpastes with “naked eye” due to the obvious color change of testing solution, showing its potentially practical application.

Two new polyketide derivatives, huaspenones C and D (1 and 2, resp.), were isolated from the cultures of an endophytic fungus Peyronellaea sp. HS-12, derived from the stems of Huperzia serrata. They share N-bearing furan-3(2H)-one backbone, and 2 has an unprecedented furo[3,2-c]pyridine skeleton. Their structures including the absolute configuration were elucidated by extensive spectroscopic analysis combined with quantum-chemical calculations. (2E,4E)-6-hydroxy-2-methylocta-2,4-dienoic acid (3), a key intermediate of the biosynthesis of 1 and 2, was also obtained from the endophyte.

Natural fiber reinforced composites have become excellent candidates for automotive applications and civil engineering facilities. The design procedures will require precisely evaluating the toughness of the materials, which demand accurate measurements of strain or displacement that are difficult to obtain for ductile materials. The primary objectives of this paper were to develop reliable experimental approaches which can effectively evaluate the fracture behaviors of random short natural fiber reinforced polypropylene (PP) composites. The digital image correlation method (DICM) was applied to compute the deformation fields around the crack tip of a compact-tension specimen in a process of loading. An experimental and numerical hybrid method was used to describe the fracture behaviors of the composites. The relationship between the micro-structure of random fibers and the macroscopic mechanical properties of the composites can also be understood.

Natural short fiber reinforced polypropylene (PP) composite has great significance both in commercial and environmental and is widely used in motor industry. Its local inhomogeneity and interphase both affect the macroscopic properties of the composite. These phenomena are still difficult to observe and study accurately in the experiment. A cohesive zone model (CZM) based numerical simulation method is presented in this paper. The three-phase (matrix-interphase-fiber) model considering some different factors was developed to study the effects of interphase parameters on the mechanical properties of the composite.

CD36, a scavenger receptor, plays an important role in the progression of atherosclerosis through its interaction with oxidized low-density lipoprotein (ox-LDL). Porphyromonas gingivalis (P. gingivalis, Pg) has been shown to promote macrophage-derived foam cell formation by affecting the expression of CD36. However, the regulatory role of CD36 in macrophages infected with Pg remains largely unknown. Therefore, the aim of the present study was to explore the molecular mechanism of Pg induced CD36 expression in macrophages. Our results showed that Pg promoted ox-LDL uptake by macrophages and the formation of foam cells. Pg infection increased CD36 mRNA and protein levels in ox-LDL-untreated macrophages. Moreover, small interferon RNA (siRNA) targeting CD36 significantly reduced foam cell formation induced by Pg. Additionally, Pg stimulated nuclear translocation of p65, which directly bound to the promoters of CD36 to facilitate its transcription. Inhibition of p65, NF-κB or ERK1/2 blocked Pg-induced CD36 production; whereas, overexpression of NF-κB subunits p65 and p50 upregulated CD36. Furthermore, Ras inhibitors significantly attenuated ERK1/2 activation and CD36 expression. Taken together, the data indicated that stimulation of the ERK/NF-κB pathway by Pg led to transactivation of the CD36 promoters, thereby upregulating CD36 expression in the infected macrophages. These findings may help design new treatment strategies in atherosclerosis.

International audience; Roscovitine (CYC202) is often referred to as a "selective inhibitor of cyclin-dependent kinases." Besides its use as a biological tool in cell cycle, neuronal functions, and apoptosis studies, it is currently evaluated as a potential drug to treat cancers, neurodegenerative diseases, viral infections, and glomerulonephritis. We have investigated the selectivity of (R)-roscovitine using three different methods: 1) testing on a wide panel of purified kinases that, along with previously published data, now reaches 151 kinases; 2) identifying roscovitine-binding proteins from various tissue and cell types following their affinity chromatography purification on immobilized roscovitine; 3) investigating the effects of roscovitine on cells deprived of one of its targets, CDK2. Altogether, the results show that (R)-roscovitine is rather selective for CDKs, in fact most kinases are not affected. However, it binds an unexpected, non-protein kinase target, pyridoxal kinase, the enzyme responsible for phosphorylation and activation of vitamin B 6. These results could help in interpreting the cellular actions of (R)-roscovitine but also in guiding the synthesis of more selective roscovitine analogs.

Rubrerythrin (Rr) is a non-heme iron protein isolated from anaerobic sulfate-reducing bacteria. Rr is a dimeric molecule, each monomer contains a Fe(SCys)4 center in the C-terminal domain and a binuclear metal center in the N-terminal domain. Rr structures with different protein sources and/or preparation procedures have been studied. Two Rr crystal structures have been solved with significant differences in their binuclear metal centers. The first structure, which was obtained from expressed protein under aerobic conditions, has a diiron–oxo center. The second structure, which was obtained from native protein of Desulfovibrio vulgaris under aerobic conditions, has an Fe–Zn center with the zinc position differing from the corresponding iron position in the former structure by approximately 2 A. The crystal structures of Rr isolated from D. vulgaris (Hildenborough, NCIB 8303), the same as the second structured but prepared under anaerobic conditions, are reported in this paper. The binuclear metal center in these structures is an Fe–Zn center. When the crystal was exposed to air, the zinc atom moved gradually, approximately 2 A, accompanied by the entrance of a water molecule (or hydroxyl group) and changes in the binuclear metal center microenvironment. This finding can explain the differences between the two different structures. The results suggest that the zinc movement may be related to the enzymatic activity of Rr. Electronic supplementary material is available if you access this article at http://dx.doi.org/10.1007/s00775-002-0400-0. On that page (frame on the left side), a link takes you directly to the supplementary material.

AIM: To investigate urotensin-II (UII) and its effects on tumor necrosis factor (TNF)-α and interleukin (IL)-1β in early acute liver failure (ALF). METHODS: We investigated the time-dependent alteration in UII levels and its effects on TNF-α and IL-1β in liver and blood in the early stage of lipopolysaccharide/D-galactosamine-induced ALF. RESULTS: After lipopolysaccharide/D-galactosamine challenge, UII rose very rapidly and reached a maximal level 0.5 h, and the level remained significantly elevated after 2 h (P < 0.05). Six hours after challenge, UII began to degrade, but remained higher than at 0 h (P < 0.05). Pretreatment with urantide, an inhibitor of the UII receptor, suppressed the degree of UII increase in liver and blood at 6 h after challenge (P < 0.05 vs paired controls). In addition, liver and blood TNF-α increased from 1 to 6 h, and reached a peak at 1 and 2 h, respectively; however, IL-1β did not rise until 6 h after challenge. Urantide pretreatment inhibited the degree of TNF-α and IL-1β increase following downregulation of UII post-challenge (all P < 0.05). CONCLUSION: UII plays a role in the pathogenesis and priming of ALF by triggering an inflammatory cascade and driving the early release of cytokines in mice.

In the present study, we aimed to develop and validate a rapid and sensitive, Alu-based real-time PCR method for the detection of circulating cell-free DNA (cfDNA). This method targeted repetitive elements of the Alu reduplicative elements in the human genome, followed by signal amplification using fluorescence quantification. Standard Alu-puc57 vectors were constructed and 5 pairs of specific primers were designed. Valuation was conducted concerning linearity, variation and recovery. We found 5 linear responses (R1–5=0.998–0.999). The average intra- and inter-assay coefficients of variance were 12.98 and 10.75%, respectively. The recovery was 82.33–114.01%, with a mean recovery index of 101.26%. This Alu-based assay was reliable, accurate and sensitive for the quantitative detection of cfDNA. Plasma from normal controls and patients with myocardial infarction (MI) were analyzed, and the baseline levels of cfDNA were higher in the MI group. The area under the receiver operating characteristic (ROC) curve for Alu1, Alu2, Alu3, Alu4, Alu5 and Alu (Alu1 + Alu2 + Alu3 + Alu4 + Alu5) was 0.887, 0.758, 0.857, 0.940, 0.968 and 0.933, respectively. The optimal cut-off value for Alu1, Alu2, Alu3, Alu4, Alu5 and Alu to predict MI was 3.71, 1.93, 0.22, 3.73, 6.13 and 6.40 log copies/ml. We demonstrate that this new method is a reliable, accurate and sensitive method for the quantitative detection of cfDNA and that it is useful for studying the regulation of cfDNA in certain pathological conditions. Alu4, Alu5 and Alu showed better sensitivity and specificity for the diagnosis of MI compared with cardiac troponin I (cTnI), creatine kinase MB (CK-MB) isoenzyme and lactate dehydrogenase (LDH). Alu5 had the best prognostic ability.

Using the crystal structure of allophycocyanin from cyanobacteriumSpirulina platensis (APC-SP) as a search model, the crystal structure of allophycocyanin from red algaePorphyra yezoensis (APC-PY) has been studied by molecular replacement methods. The APC-PY crystals (Form 3) belong to the space group of R32, cell dimensions a =b = 10.53 nm,c = 18.94 nm, alpha= beta = 90 degrees , gamma= 120 degrees ; there is one alphabeta monomer in each crystallographic asymmetric unit in the cell. The translation function search gave a unique peak with a correlation coefficient (Cc) of 67.0% and an R-factor of 36.1 % for reflection data from 1.0 to 0.4 nm. Using the results by molecular replacement, the initial model of APC-PY was built, and the coincidence of the chromophore in APC-PY initial model with its2F (o)- F(c) OMIT map further confirms the results by molecular replacement.

The structure of desheptapeptide (B24-B30) insulin (DHPI) in a new crystal form (form B) has been determined and refined to 0.2 nm resolution. The crystals were obtained under the same crystallization condition as previously reported crystal form (form A). The overall structures of the two crystal forms are similar but obvious differences can be observed in crystal packing and local conformation. The crystal structures of the two forms show that the two independent molecules in an asymmetric unit from a DHPI dimer, and the dimer formation buries more than 18.20 and 16.95 nm(2) of solvent accessible surfaces for form A and form B DHPI, respectively, the largest among insulin and insulin analogs ever reported. Close examination at crystal packing shows that the dimer-forming surface of DHPI, namely Surface II, is normally present in the association of insulin and insulin analogs in their crystal structures. The results demonstrate that Surface II is crucially important for the formation of two crystal forms under the same crystallization condition.

The crystal structure of R-Phycoerythrin (R-PE) from Polysiphonia urceolata has been refined to a resolution of 1.9 A, based on the atomic coordinates of R-PE determined at 2.8 A resolution, through the use of difference Fourier method and steorochemistry parameters restrained refinement with model adjustment according to the electron density map. Crystallographic R-factor of the refined model is 0.195 (Rfree = 0.282) from 8-1.9 A. High resolution structure of R-PE showed precise interactions between the chromophores and protein residues, which explained the spectrum characteristic and function of chromophores. Four chiral atoms of phycourobilin (PUB) were identified as C(4)-S, C(16)-S, C(21)-S, and C(20)-R. In addition to the coupling distances of 19 A to 45 A between the chromophores which were observed and involved in the energy transfer pathway, high resolution structure of R-PE suggested other pathways of energy transfer, such as the ultrashort distance between alpha140a and beta155. It has been proposed that aromatic residues in linker proteins not only influence the conformation of chromophore, but may also bridge chromophores to improve the energy transfer efficiency.

To explore the relationship of Pi-deficiency syndrome in TCM with the change of serum high density lipoprotein (HDL) in blood lipid metabolic disorder.Sixty-eight patients with confirmed coronary heart disease (CHD) were selected for TCM syndrome typing into Pi-deficiency (PD) group and non-Pi-deficiency (NPD) group. Routine blood lipids and serum lipoprotein electrophoretogram (SLPG) were determined in all patients to analyze the total content of HDL and its relative contents of sub-components HDL(1-5), as well as their relation with PD syndrome. Besides, a healthy control group (62 cases) was set up.The level of serum HDL-C was lowered, SLPG abnormality rate increased in the patients with CHD, with total HDL and the relative contents of subcomponent HDL(1) and HDL(3) significantly lower than those in the healthy control group (P0.01). The total HDL, HDL(1) and HDL(3) in the PD group were also lower than those in the NPD group (P0.05, P0.01).Serum HDL and its sub-components showed a definite relation with TCM PD syndrome type, therefore, further exploring the granular specificity of HDL and its sub-components as well as their influence on reverse cholesterol transport (RCT) may hopefully provide clues for developing RCT regulatory Chinese new drugs and for CHD prevention and treatment.

Desheptapeptide (B24-B30) insulin (DHPI), a virtually inactive insulin analog, has been crystallized in space group P2, 2, 2, with two DHPI molecules in an asymmetric unit. The orientatin and positions of the molecules were determind by molecular replacement. and a structural model was built at 0.3 nm resolution. The current model shows that the two DMHI monomers are related by a non-crystallographic 2-fold axis, nearly parallel to the crystallographicc axis. This structural feature complicated the determination of the orientation of the local 2-fold axis, which was later confirmed by analysing the diffraction data of DHPI crystals.

The crystal structure of desheptapeptide (B24–B30) insulin (DHPI), a virtually inactive analog of insulin, was determined at 1.6 Å resolution. In the refined structure model, DHPI retains three α-helices (A1–A8, A12–A18, and B9–B19) as its structural framework, while great conformational changes occur in the N and C termini of B-chain. The β-turn, which lies in B20–B30 in insulin and insulin analogs with high potency, no longer exists in DHPI. Relative motion is observed among the three α-helices, each as a rigid functional group. In contrast, a region covering B5–B6 and A6–A11 exhibits a relatively stable conformation. We interpret our results as identifying: ( i ) the importance of β-turn in determining the receptor-binding potency of insulin and ( ii ) a leading role of Phe B24 in maintaining the β-turn structure.

RecR is an important recombination mediator protein in the RecFOR pathway. RecR together with RecO and RecF facilitates RecA nucleoprotein filament formation and homologous pairing. Structural and biochemical studies of Thermoanaerobacter tengcongensis RecR (TTERecR) and its series mutants revealed that TTERecR uses the N-N dimer as a basic functional unit to interact with TTERecO monomer. Two TTERecR N-N dimers form a ring-shaped tetramer via an interaction between their C-terminal regions. The tetramer is a result of crystallization only. Hydrophobic interactions between the entire helix-hairpin-helix domains within the N-terminal regions of two TTERecR monomers are necessary for formation of a RecR functional N-N dimer. The TTERecR N-N dimer conformation also affects formation of a hydrophobic patch, which creates a binding site for TTERecO in the TTERecR Toprim domain. In addition, we demonstrate that TTERecR does not bind single-stranded DNA (ssDNA) and binds double-stranded DNA very weakly, whereas TTERecOR complex can stably bind DNA, with a higher affinity for ssDNA than double-stranded DNA. Based on these results, we propose an interaction model for the RecOR:ssDNA complex.

Crystal structures of the AHL-lactonase AidH in complex with substrate and product are reported at high resolution and a catalytic mechanism is proposed for the metal-independent AHL-lactonase., Many pathogenic bacteria that infect humans, animals and plants rely on a quorum-sensing (QS) system to produce virulence factors. N-Acyl homoserine lactones (AHLs) are the best-characterized cell–cell communication signals in QS. The concentration of AHL plays a key role in regulating the virulence-gene expression and essential biological functions of pathogenic bacteria. N-Acyl homoserine lactonases (AHL-lactonases) have important functions in decreasing pathogenicity by degrading AHLs. Here, structures of the AHL-lactonase from Ochrobactrum sp. (AidH) in complex with N-­hexanoyl homoserine lactone, N-hexanoyl homoserine and N-­butanoyl homoserine are reported. The high-resolution structures together with biochemical analyses reveal convincing details of AHL degradation. No metal ion is bound in the active site, which is different from other AHL-lactonases, which have a dual Lewis acid catalysis mechanism. AidH contains a substrate-binding tunnel between the core domain and the cap domain. The conformation of the tunnel entrance varies with the AHL acyl-chain length, which contributes to the binding promiscuity of AHL molecules in the active site. It also supports the biochemical result that AidH is a broad catalytic spectrum AHL-lactonase. Taken together, the present results reveal the catalytic mechanism of the metal-independent AHL-lactonase, which is a typical acid–base covalent catalysis.

Pyridoxal kinase (ATP:pyridoxal 5'-phosphotransferase; EC 2.7.1.35) is a key enzyme in the transformation of vitamin B(6) to pyridoxal-5'-phosphate. Pyridoxal-5'-phosphate is the crucial cofactor required by numerous enzymes involved in the metabolism of amino acids and the synthesis of many neurotransmitters. Pyridoxal kinase from sheep brain was crystallized in an orthorhombic form using the hanging-drop vapour-diffusion method with sodium citrate as the precipitant. The crystals belong to space group P2(1)2(1)2(1), with unit-cell parameters a = 59.8, b = 94.4, c = 128.2 A, and diffract to a resolution of 2.1 A. Crystals were transferred into a soaking liquid without citrate and two heavy-atom derivatives were prepared.

Manganese superoxide dismutase (GP-MnSOD), a component of the so-called `green protein' (green protein complex) from the facultative anaerobic halodenitrifier Bacillus halodenitrificans , has been crystallized using the hanging-drop vapor diffusion method. Crystals have unit-cell parameters a = b =93.4 A, c =65.0 A, and belong to the space group P4 3 2 1 2. Preliminary analysis indicates there is one monomer in each asymmetric unit. The structural information from this enzyme will enrich our knowledge on its high catalytic activity and its possible role in green protein complex.

Type I DNA methyltransferases contain one specificity subunit (HsdS) and two modification subunits (HsdM). The electron microscopy model of M.EcoKI-M2S1 methyltransferase shows a reasonable closed state of this clamp-like enzyme, but the structure of the open state is still unclear. The 1.95 A crystal structure of the specificity subunit from Thermoanaerobacter tengcongensis (TTE-HsdS) shows an unreported open form inter-domain orientation of this subunit. Based on the crystal structure of TTE-HsdS and the closed state model of M.EcoKI-M2S1, we constructed a potential open state model of type I methyltransferase. Mutational studies indicated that two α-helices (aa30-59 and aa466-495) of the TTE-HsdM subunit are important inter-subunit interaction sites in the TTE-M2S1 complex. DNA binding assays also highlighted the importance of the C-terminal region of TTE-HsdM for DNA binding by the TTE-M2S1 complex. On the basis of structural analysis, biochemical experiments and previous studies, we propose a dynamic opening and closing mechanism for type I methyltransferase.