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The diet structure of diabetic patients is different from that of normal people. Diabetic patients also need to take hypoglycemic drugs to regulate blood sugar. Both dieting and drugs affect the gut microbiota of diabetic patients. In this letter, we discuss that different dietary patterns and the use of hypoglycemic agents may have an impact on changes in gut microbiota in diabetic patients.

Confirming positive effects and offering optimal ranges of tea saponins on improving the efficiency of phytoremediation on cadmium is a prerequisite for applying tea saponins in field remediation. Existing studies qualitatively tested the feasibility of tea saponins on promoting the absorption of cadmium by hyperaccumulators in pots experiments, while this study investigated the effects of tea saponins on increasing the proportion of cadmium available fraction in contaminated soil quantitatively and confirmed tea saponins promoted the absorption by Portulaca oleracea in cadmium-contaminated water by independent soil experiments and hydroponic experiments. The results showed that for acquiring a higher proportion of cadmium available fraction, the concentration of tea saponins was negatively correlated with the concentration of cadmium contained in the soil, and the optimal treatment time of tea saponins was between 3–9 days depending on the cadmium concentration in contaminated soil. Using tea saponins could enhance the absorption of cadmium by Portulaca oleracea in a relatively short time to decrease the concentration of cadmium left in the contaminated water. The above findings help to deepen the understanding of tea saponins’ effects and use ranges on phytoremediation of cadmium both in soil and water and conduce studies on phytoremediation of other heavy-metal-contaminated soil and water with the help of tea saponins.

Aim: To investigate the efficiency of two new fast-acting enzymes, recombinant arylsulfatase (IMCS-PSF) and mutant β-glucuronidase from Escherichia coli (IMCSzyme), in hydrolyzing specific terbutaline metabolites. Materials & methods: Two purified novel enzymes are used to precisely determine the amount of each metabolite in urine at different time points after oral administration. After systematically evaluating the hydrolysis efficiency of the novel enzymes compared with commercially available enzymes, these recently developed enzymes were applied to establish the separate urine concentration profiles of terbutaline and each metabolite. Results & discussion: The results highlight the highly efficient arylsulfatase enzyme expressed from E. coli for urine analysis of terbutaline while suggesting sulfoconjugates as the main terbutaline metabolites. Conclusion: This study demonstrated the high efficiency of the IMCS-PSF enzyme in hydrolyzing terbutaline conjugates in comparison with other enzyme reagents typically used for the analysis of terbutaline and sulfoconjugates are the main terbutaline metabolites in urine.

Spectroscopic techniques, electrochemical methods, nanozymes, computer vision, and modified chromatographic techniques are the emerging techniques for determining the quality and safety parameters (e.g., physical, chemical, microbiological, and classified parameters, as well as inorganic and organic contaminants) of tea products (such as fresh tea leaves, commercial tea, tea beverage, tea powder, and tea bakery products) effectively. By simplifying the sample preparation, speeding up the detection process, reducing the interference of other substances contained in the sample, and improving the sensitivity and accuracy of the current standard techniques, the abovementioned emerging techniques achieve rapid, cost-effective, and nondestructive or slightly destructive determination of tea products, with some of them providing real-time detection results. Applying these emerging techniques in the whole industry of tea product processing, right from the picking of fresh tea leaves, fermentation of tea leaves, to the sensory evaluation of commercial tea, as well as developing portable devices for real-time and on-site determination of classified and safety parameters (e.g., the geographical origin, grade, and content of contaminants) will not only eliminate the strong dependence on professionals but also help mechanize the production of tea products, which deserves further research. Conducting a review on the application of spectroscopic techniques, electrochemical methods, nanozymes, computer vision, and modifications of chromatographic techniques for quality and safety determination of tea products may serve as guide for other types of foods and beverages, offering potential techniques for their detection and evaluation, which would promote the development of the food industry.

Resulting from the year‐on‐year increase in tea plantations and the saturated consumption of tea leaves, the relative overcapacity in China's tea‐leaf production appears. Discovering the new utilization of tea leaves is helpful to alleviate this phenomenon. The feasibility of extracting saponins from aged tea leaves was investigated and confirmed; three major variables in water extraction were optimized by Box‐Behnken designs. The significant variable found in Box‐Behnken designs, liquid–solid ratio, was went through single‐variable experiments for a more accurate optimization. Seventy‐five ml/g, 1 hr, and 80°C were optimal values and tea‐leaf saponins yield of tea tree variety Longjing 43 reached 12.19% ± 0.0030% after optimizations, higher than the yield of tea‐seed saponins from Camellia oleifera seed meals using the same extraction method (water extraction based on optimizations). According to correlation analyses, tea tree's leaf type and germination stage affected tea‐leaf saponins contents positively, indicating tea trees with larger leaves and later germination stage would have a higher content of tea‐leaf saponins with a higher yield of tea‐leaf saponins under the same extraction method.

Compared with green tea powder, whether enzyme-deactivated by steam or pan-fire, matcha is rich in nutrients, but is more expensive. Using steamed green tea powder to adulterate matcha often occurs...

Tea saponins, found in Camellia plants, are natural non-ionic surfactants that offer obvious beneficial effects in soil remediation. Most tea saponins are extracted from the Camellia oleifera seed meal, with the leaves and flowers of Camellia sinensis as potential sources. Water extraction and ultrasound-assisted water extraction combined with acetone precipitation are recommended for the industrial extraction and purification of tea saponins, considering multiple factors. The detailed physical, chemical and biochemical properties of tea saponins need to be clarified, especially whether tea saponins with slightly different structures from distinct sources have different soil remediation properties. Applied in leaching remediation, phytoremediation and microbial remediation, tea saponins desorb heavy metals from contaminated soil as well as enhancing their bioavailability. Tea saponins improve the accumulation of pollutants by hyperaccumulators as well as the degradation of organic pollutants by microorganisms. Currently the mechanisms of tea saponins are not clear, although they are proven to be effective natural surfactants for the remediation of contaminated soils. This review enriches our understanding of tea saponins from various aspects and encourages further studies of industrial extraction and purification, and the field remediation mechanisms of tea saponins, making better use of Camellia plants and contributing to environmental protection.

Box-Behnken design was advantageous to parameters optimization of differential pulse anodic stripping voltammetry (DPASV) for the analysis of lead(II) with its high efficiency and accuracy. Five Box-Behnken designs were designed and conducted in the electrolyte of 0.1 mol/L acetate buffer and 0.1 mol/L HCl without the removal of oxygen. Significant parameters and interactions in each electrolyte were found (P-value

Bearing the merits of rapid, minimally destructive, and simultaneous multi-element analyses, laser-induced breakdown spectroscopy (LIBS) shows its unique advantages in quantitative analyses of lead, cadmium, and hexavalent chromium in plant materials. However, the greatest challenge LIBS must confront is calibration. Various methods for calibration are proposed and put into effect; nevertheless, limits of detection acquired by LIBS are not acceptable when they are compared with the maximum residue limits drawn up by governments, and LIBS's performances in quantitative analyses are to be improved. This review summarizes recent studies of analyzing lead, cadmium, and hexavalent chromium in plant materials quantitatively by LIBS; weighs the strengths and weaknesses of their calibration methods; and recommends the combination of matrix-matched standards based on spiked sample materials and internal standard as well as chemometrics in complicated situations for calibration in LIBS. Selecting the emissi...

Cyclodextrin (CD) inclusions are generally used to increase the solubility of poorly soluble drugs. In this study, magnolol (MAG) was used as a model drug for exploring the effects of CD on the degradation of pharmaceutical drugs by intestinal microflora. MAG/β-cyclodextrin (β-CD) and MAG/hydroxypropyl-β-CD (HP-β-CD) inclusion complexes were successfully prepared by the saturated aqueous solution and freeze-drying methods, respectively. Structural characterisation along with analyses of solubility, residual water content and drug content of the inclusion complexes was performed. The intestinal microflora of male rats was used to study MAG degradation in vitro. At three concentrations, the degradation of both the inclusion complexes was slower than that of the MAG monomer, MAG and CD mixtures and the MAG-poloxamer 188 micelle. There were no statistically significant differences in the degradation of the MAG/β-CD and MAG/HP-β-CD inclusion complexes. A simulation first-order equation of the degradation parameters revealed that the degradation of the inclusion complexes was slower and pronounced, judging by slope. The experimental findings were verified by molecular docking for predicting the stable molecular structure of the inclusion complexes. In conclusion, the inclusion complexes partially protected MAG from degradation by the intestinal bacteria.

Endometriosis is an estrogen-dependent disease. Farnesoid X receptor (FXR) activation has been shown to inhibit estrogen signaling in breast cancer and testicular tumors. However, the role of FXR in endometriosis is still poorly understood. Here, we aimed to investigate whether FXR activation by its synthetic agonist GW4064 has a therapeutic effect on endometriosis and the underlying molecular mechanisms. We found that the expression of FXR (encoded by the NR1H4 gene) in endometriotic tissues and stromal cells (ESCs) was higher than that in eutopic endometrial tissues and stromal cells. The GW4064 treatment led to a dose-dependent decrease in aromatase and estrogen receptor β (ERβ) expression and induced ERK1/2, p38, AMPK, and Stat3 activation in ESCs. In contrast, ERK1/2 inhibitor reversed the GW4064-induced reduction in aromatase expression. In addition, treatment with p38, AMPK, and Stat3 inhibitors or small interfering RNAs could also reverse the GW4064-induced reduction of ERβ expression in ESCs. The GW4064 treatment markedly increased Stat3 phosphorylation, enhancing the binding of Stat3 to the ESR2 promoter, which resulted in the downregulation of ERβ. Coimmunoprecipitation assay and chromatin immunoprecipitation analysis revealed that FXR was able to compete with cyclic AMP response element-binding (CREB) protein for binding to a common sequence on the aromatase promoter region after GW4064 treatment in ESCs. Moreover, treatment of endometriosis xenografts with GW4064 suppressed aromatase and ERβ expression in nude mice. Our results suggest that FXR may represent a potential therapeutic target for future therapy.

In this paper, we study non-cosemisimple Hopf algebras through their underlying coalgebra structure. We introduce the concept of the maximal pointed subcoalgebra/Hopf subalgebra. For a non-cosemisimple Hopf algebra A with the Chevalley property, if its diagram is a Nichols algebra, then the diagram of its maximal pointed Hopf subalgebra is also a Nichols algebra. When A is of finite dimension, we provide a necessary and sufficient condition for A’s diagram equaling the diagram of its maximal pointed Hopf subalgebra.

The relative overcapacity in China's tea-leaf production and the potential application of tea-leaf saponins in soil remediation encouraged in-depth developments and comprehensive utilizations of tea-leaf resources. Through variables optimizations using Box&ndash, Behnken designs for ultrasonic power, temperature as well as ultrasonic treatment time in ultrasonic-assisted water extraction and single-variable experiments for acetone-extraction solution ratio in acetone precipitation, a rapid and simple method was developed for preparing tea-leaf saponins. Tea-leaf saponins with the concentration of 3.832 &plusmn, 0.055 mg/mL and the purity of 76.5% &plusmn, 1.13% were acquired under the optimal values of 78 w, 60 &deg, C, 20 min and 0.1 ratio of acetone-extraction solution. Both Fourier transform-infrared (FT-IR) spectra and ultraviolet (UV) spectra revealed slight composition differences between tea-leaf saponins and tea-seed saponins, while these differences were not reflected in the critical micelle concentration (CMC) and the surface tension of tea-leaf saponins and tea-seed saponins, indicating there was no need to distinguish them at the CMC. Further research attention on where tea-leaf saponins were in low concentrations is deserved to discover whether they had differences in comparison with tea-seed saponins, which was beneficial to apply them in the phytoremediation of contaminated soils.

Resulting from the year-on-year increase in tea plantations and the saturated consumption of tea leaves, the relative overcapacity in China's tea-leaf production appears. Discovering the new utilization of tea leaves is helpful to alleviate this phenomenon. The feasibility of extracting saponins from aged tea leaves was investigated and confirmed; three major variables in water extraction were optimized by Box-Behnken designs. The significant variable found in Box-Behnken designs, liquid-solid ratio, was went through single-variable experiments for a more accurate optimization. Seventy-five ml/g, 1 hr, and 80°C were optimal values and tea-leaf saponins yield of tea tree variety Longjing 43 reached 12.19% ± 0.0030% after optimizations, higher than the yield of tea-seed saponins from

The capacity of pomelo peels’ adsorption on lead(II) from aqueous solutions without modifications was investigated and confirmed. Four variables in this study, pH, temperature, time and initial concentration of lead(II), significantly affected the adsorption rate of pomelo peels. The prediction model and optimal ranges of optimized variables were given by Doehlert designs, which made the selection of variables rapid, flexible and effortless to obtain an adsorption rate reaching 99.9% and 20 mg/L for initial lead(II) concentration, 3 for pH, 50 °C for temperature and 210 min for time was a choice. The higher correlation coefficient as well as the more consistent value of experimental equilibrium adsorption capacity of the pseudo-first-order model suggested it bore a better prediction of the adsorption kinetics than the pseudo-second-order model. Langmuir model indicated the adsorption mechanism of pomelo peels was monolayer sorption with the help of both physical adsorption and chemical bonding, which were demonstrated by scanning electron microscopy and Fourier transform-infrared, respectively. The ability of pomelo peels to adsorb lead(II) from aqueous solutions was not interfered with the presence of calcium(II), magnesium(II), copper(II) and zinc(II). Pomelo peels had the potential to be utilized in the simultaneous adsorption of toxic heavy metal ions.

Kaposi sarcoma-associated herpesvirus (KSHV) stimulates proliferation, angiogenesis, and inflammation to promote Kaposi sarcoma (KS) tumor growth, which involves various growth factors and cytokines. Previously, we found that KSHV infection of human umbilical vein endothelial cells (HUVECs) induces a transcriptional induction of the proangiogenic and proinflammatory cytokine angiopoietin-2 (Ang-2). Here, we report that KSHV induces rapid release of Ang-2 that is presynthesized and stored in the Weibel-Palade bodies (WPB) of endothelial cells upon binding to its integrin receptors. Blocking viral binding to integrins inhibits Ang-2 release. KSHV binding activates the integrin tyrosine kinase receptor signaling pathways, leading to tyrosine phosphorylation of focal adhesion kinase (FAK), the tyrosine kinase Src, and the Calα2 subunit of the l -type calcium channel to trigger rapid calcium (Ca 2+ ) influx. Pretreatment of endothelial cells with specific inhibitors of protein tyrosine kinases inhibits KSHV-induced Ca 2+ influx and Ang-2 release. Inhibition of Ca 2+ mobilization with calcium channel blockers also inhibits Ang-2 release. Thus, the interaction between KSHV and its integrin receptors plays a key role in regulating rapid Ang-2 release from endothelial cells. This finding highlights a novel mechanism of viral induction of angiogenesis and inflammation, which might play important roles in the early event of KS tumor development.

The relationships between piecewise-Koszul algebras and other “Koszul-type” algebras are discussed. The Yoneda-Ext algebra and the dual algebra of a piecewise-Koszul algebra are studied, and a sufficient condition for the dual algebra A! to be piecewise-Koszul is given. Finally, by studying the trivial extension algebras of the path algebras of Dynkin quivers in bipartite orientation, we give explicit constructions for piecewise-Koszul algebras with arbitrary “period” and piecewise-Koszul algebras with arbitrary “jump-degree”.

The monomeric cobalt-phosphite-thiolato complex [ Co (mpt)2 {P (OCH3 )3 }2 ] BF4 (Hmpt = 2-mercaptothiazoline) has been prepared and characterized by X-ray crystallography. The complex crystallizes in the monoclinic space group C2/c with a = 0.8078(5), b = 2.6020(18), c= 1.2191(7) nm, β= 99.38 (1)°, V = 2.528(3) nm3, and Z = 4. The structure comprises discrete cations [Co (mpt)2(P(OCH3)3}2] + and anions BF4−, in which the cobalt (III) atom is coordinated to two chelate mpt− and two cis-oriented monodentate P(OCH3)3 ligands in a highly distorted octahedral geometry. The most distorted angles are S(2)-Co(1)-S(2a) of 162.23(10)° and N (l)-Co(1)-S(2) of 71.47 (13)°, the latter is caused by the geometric constraint of the bidentate ligand mpt−. Cyclic voltammetry has been used to study the electrochemical behavior of the title complex on the Pt electrode in MeCN solution with 0.1 mol · L−1 of Bu4n NBF4 89 electrolyte, The dts indicate that the title complex is unstable in MeCN.

We present two years (January 2007–December 2008) of atmospheric SO 2 , NO 2 and NH 3 measurements from ten background or rural sites in nine provinces in China. The measurements were made on a monthly basis using passive samplers under careful quality control. The results show large geographical and seasonal variations in the concentrations of these gases. The mean SO 2 concentration varied from 0.7 ± 0.4 ppb at Waliguan on Qinghai Plateau to 67.3 ± 31.1 ppb at Kaili in Guizhou province. The mean NO 2 concentration ranged from 0.6 ± 0.4 ppb at Waliguan to 23.9 ± 6.9 ppb at Houma in southern Shanxi. The mean NH 3 concentration ranged from 2.8 ± 3.0 ppb at Shangdianzi in northeastern Beijing to 13.7 ± 8.4 ppb at Houma. At most sites, SO 2 and NO 2 peaked in winter and reached minima in summer, while NH 3 showed maximum values in summer and lower values in cold seasons. On the whole, the geographical distributions of the observed gas concentrations are consistent with those of emissions. The ground measurements of SO 2 and NO 2 are contrasted to the SCIAMACHY SO 2 and OMI NO 2 tropospheric columns, respectively. Although the satellite data can capture the main features of emissions and concentrations of SO 2 , they do not reflect the variations of SO 2 in the surface layer. The situation is better for the case of NO 2 . The OMI NO 2 columns capture the geographical differences in the ground NO 2 and correlate fairly well with the ground levels of NO 2 at six of the ten sites.

Here we presented a facile electrochemical deposition route for the controllable preparation of La3+/ZnO hierarchical nanostructures, such as flower-like nanostructures consisted of nanorods, flower bundles, and hexagonal nanorods with nests at the top. These prepared La3+/ZnO deposits were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV–vis spectrophotometer, and photoluminescence spectroscopy. The formation process of La3+-doped ZnO and the growth mechanisms of La3+/ZnO hierarchical nanostructures were discussed. The UV and PL spectra measurements show that the surface morphologies of La3+/ZnO deposits have an obvious effect on their optical properties and we can easily adjust their optical properties as well as La3+/ZnO nanostructures by changing electrochemical deposition parameters. In addition, the magnetic properties of La3+/ZnO deposits were also investigated.

Rare-earth ion-doped ZnO has been the focus of numerous investigations because of its unique optical properties and promising applications in optoelectronic devices. Here we presented a facile electrochemical deposition route for the controllable preparation of Eu3+/ZnO nanostructures on a large scale. The prepared Eu3+/ZnO deposits were characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, selected area electron diffraction, and X-ray photoelectron spectroscopy. Herein, the growth mechanisms of Eu3+/ZnO nanosheets and nanorods were discussed. The formation process of Eu3+/ZnO foam-like nanostructures is illuminated in this paper. The room temperature photoluminescence properties of the Eu3+/ZnO foam-like nanostructures were investigated. The sharp 4f-4f transition emissions of Eu3+ can be directly observed at 593, 617, and 698 nm. An energy transfer between ZnO and Eu3+ is shown to occur under UV excitation.

We report here a facile and efficient synthesis route for the preparation of symmetrical PbTe dendritic structures consisted of orderly and regular particles via electrochemical deposition without any templates. The electrochemical reactions relevant to the growth of PbTe intermetallic compounds were studied by cyclic voltammetry, and the formation mechanism of PbTe dendritic structures was investigated. The electrode potential oscillation was relevant to the formation of the PbTe dendrites. The sizes of the particles in dendritic structures were tunable from 100 to 500 nm and the shapes could be controlled to be either starlike or trigonal. These prepared PbTe dendrites were characterized by SEM, EDS, XRD, HRTEM, and SAED, respectively. The DSC analyses were conducted to study the thermal properties of the prepared PbTe dendritic structures. The high transmittance of the PbTe dendritic structures between 500 and 4000 nm were observed, and the band gap energy of the prepared PbTe was calculated about 0.27...

Here we report the preparation of porous CeO2 and clusters of CeO2 nanosheet arrays via a simple, efficient electrochemical approach. Gas bubbles functioning as a dynamic template were utilized in our research for the synthesis of nanosheet array clusters. The Hc and Mr values of porous CeO2 are almost the same as those of CeO2 nanosheet array clusters at 5 K, and they are about 5916 Oe and 8.83 x 10(-4) emu, respectively. However, the saturation magnetization of CeO2 nanosheet array clusters is much larger than that of porous CeO2 structures. The magnetic property of the prepared CeO2 deposits may be caused by the existence of Ce(III), indicating potential interest in the nanodevices because of their electronic and magnetic properties.

Estrogen receptor beta (ERβ, encoded by ESR2 gene) and cytochrome P450 aromatase (encoded by CYP19A1 gene) play critical roles in endometriosis, and the levels of insulin-like growth factor-I (IGF-I) in the peritoneal fluid are significantly higher in patients with endometriosis compared with those in normal women. However, the effects and mechanisms of IGF-I on ERβ and aromatase expression remain to be fully elucidated. In this study, human endometriotic stromal cells (ESCs) and endometrial cells (EMs) derived from ovarian endometriomas and eutopic endometrial tissues. ESCs were cultured with IGF-I, signal pathway inhibitors, and siRNAs. ERβ and aromatase expression were measured by real-time PCR and Western, respectively. The binding of c-Jun and CREB to the ESR2 and CYP19A1 promoters was assessed by chromatin immunoprecipitation assay. Animal experiments were performed in a xenograft mouse model. Levels of IGF-I mRNA in ESCs were markedly higher than those in EMs. IGF-I upregulated ERβ and aromatase expression in ESCs after stimulation of the IGF1R/PI3K/AKT pathway. Following IGF-I treatment, a marked increase in c-Jun and CREB phosphorylation occurred, enhancing binding to the ESR2 and CYP19A1 promoters. An IGF1R inhibitor in vivo reduced IGF-I-induced endometriosis graft growth and ERβ and aromatase expression. In conclusion, this is the first report to describe a mechanistic analysis of ERβ and aromatase expression regulated by IGF-I in ESCs. Moreover, an IGF1R inhibitor impeded ectopic lesion growth in nude mice. These findings suggest that an inhibitor of IGF1R might have therapeutic potential as an antiendometriotic drug.Level of IGF-I mRNA in ESCs is markedly higher than that in EMs. IGF-I up-regulates ERβ and aromatase expression via IGF1R/PI3K/AKT pathway. C-Jun and CREB are recruited to ESR2 or CYP19A1 promoter by IGF-I stimulation. IGF-1R inhibitors in vivo impede the growth of ectopic lesions in nude mice.

To investigate the progress and application of near infrared spectroscopy (NIR) used to detect amino acids in the growth of crops and food processing process. With online searching databases including ISI (Web of Knowledge), CNKI (China Knowledge Network), summarize the detection of chemical value using high performance liquid chromatography (HPLC) and chemometric methods involved in the application of NIR used to analyze amino acids in food, meanwhile summarize the data, materials and main topics in relevant original literature. Overview the methods of chemical value detection using HPLC and chemometric analysis, their applications in detecting the quality of crops, determining the content of water, amino acids and polyphenol in green tea, detecting the quality of feed and determining the content of amino acids in cheese, ham and meat products, We forecasted the application of NIR in determining the content of amino acids in food and analyzed its merits and drawbacks. The development of NIR's application in amino acids detection should be based on the HPLC detection, and the problem of model transfer mainly restricts its large-scale promotion currently. Online analysis can monitor the entire reaction and change process from raw materials to products and thus meets the needs of real-time monitoring food quality from production to sales, and it will be an important direction for future.

The extracellular matrix is a vital compartment in plants with a prominent role in defence against pathogen attack. Using a maize cell suspension culture system and pathogen elicitors, responses to pathogen attack that are localised to the extracellular matrix were examined by a proteomic approach. Elicitor treatment of cell cultures induced a rapid change in the phosphorylation status of extracellular peroxidases, the apparent disappearance of a putative extracellular beta-N-acetylglucosamonidase, and accumulation of a secreted putative xylanase inhibitor protein. Onset of the defence response was attended by an accumulation of glyceraldehyde-3-phosphate dehydrogenase and a fragment of a putative heat shock protein. Several distinct spots of both proteins, which preferentially accumulated in cell wall protein fractions, were identified. These three novel observations, viz. (i) secretion of a new class of putative enzyme inhibitor, (ii) the apparent recruitment of classical cytosolic proteins into the cell wall and (ii) the change in phosphorylation status of extracellular matrix proteins, suggest that the extracellular matrix plays a complex role in defence. We discuss the role of the extracellular matrix in signal modulation during pathogen-induced defence responses.

Two 1,5-naphthalenedisulfonate(1,5-nds)-coordinated polymeric complexes [Cu(1,5-nds) (H2O)4] n and [Cd(1,5-nds)(H2O)2] n were synthesized and their structures characterized by single-crystal structure analysis. The Cu(II) complex [Cu(1,5-nds)(H2O)4] n is obtained both from CuCl or CuCl2 reacting with 1,5-naphthalenedisulfonic acid at 80∘C. It is a one-dimensional polymer in which Cu(II) is coordinated by four water molecules and two sulfonate oxygen atoms in the trans positions. The interaction between sulfonate and Cu(II) is different in complexes obtained from different reaction temperature. While the three-dimensional Cd(II) complex [Cd(1,5-nds)(H2O)2] n is a polymorph of the reported two-dimensional layer structure, in which Cd(II) is coordinated by two water molecules in the trans positions and four different sulfonate groups, the same as that observed in the two-dimensional polymorph. However, the 1,5-nds ligands connect Cd(II) centers belonging to different layers, resulting in the three-dimensional framework.

Three silver(I) cluster-based coordination polymers, namely, [Ag3(podc)(H2O)2]·2H2O (1), [Ag2(pidc)] (2), and [Ag2(pidc)(H2O)] (3) (H3podc = 3,5-pyrazoledicarboylic acid and H2pidc = 2,3-pyrazinedicarboxylic acid) have been synthesized. Among them, 1 consists of stairlike one-dimensional chains with boxlike units as well as the zigzag tetranuclear silver(I) cluster subunits [Ag···Ag 2.778(1) and 3.230(1) A]; 2 features new parallel single-strand silver(I) helices that propagate by the 41-screw symmetry with short Ag···Ag contacts [Ag2···Ag2 3.158(1) A] along the c-axis and display the same handedness, while 3 features hexagonal Ag4(μ2-O)2 cores, in which the Ag···Ag separation is 3.150(2) A. These complexes display room temperature photoluminescence in the blue/green region, which may be assigned to an admixture of ligand-to-metal charge transfer and metal-centered (d−s/d−p) transitions.

A 2D rhombic grid network complex [Cu4(tib)8](CH3COO)8·32H2O (6) has been prepared by reaction of the tripodal ligand 1,3,5-tris(imidazol-1-ylmethyl)benzene (tib) with Cu(CH3COO)2 in aqueous solution and characterized by single crystal X-ray diffraction. In the solid state, the tripodal ligand tib acts as a 2-connected ditopic bridging ligand. Studies about the influences that control the supramolecular assembly and crystal packing process of complexes (1–6), which are assembled from tripodal ligands titmb and tib with metal atoms, not only illustrate that hydrogen bonds play a very important role in the construction of supramolecular complexes, but also that the reaction conditions together with the metal atoms co-affect inorganic supramolecular formation. Results show that the formation of N⋯H–OH hydrogen bonds between the hydrogen atoms of the solvent water molecules and the imidazole coordinative nitrogen atoms of the third arm of tib makes the tripodal ligand tib act as a 2-connected bridging ligand when it coordinates with copper(II) atoms. It is found that the conformations of the tripodal ligands tib and titmb (titmb = 1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene) are obviously controlled by the reaction conditions. When reacted in organic solvents, both of the titmb and tib are in the same W-form; when water is present in the solvent, the conformations of the two tripodal ligands will change from the W-form to the Y-form; when reacted in water, tripodal ligand tib is in a novel Y-form. Results also show that the coordination geometry of the metal atoms also plays an important role in the construction of supramolecular complexes. In 2D/3D complexes 1, 2, 5 and 6, the involved transitional metal atom is the same – all are copper(II) atoms – and the coordination geometry of copper is square-planar N4 or square-based pyramid N5 or N4O1, while in the discrete cage complexes 3 and 4, the involved transitional metal atoms are the zinc(II) and silver(I) atoms, and the coordination geometries of zinc and silver are tetrahedral N2O2 or linear N2, respectively. These studies show that the hydrogen bonds play a very important role in the crystal packing process of this infinite 2D rhombic grid network complex 6. There are no large channels formed in the 2D complexes 1 and 2, but large channels are formed by the columnar packing of the 2D (4,4) rhombic grid layers of complex 6 along the a axis, and in which the cubic O8 chains are accommodated.

Four manganese(III) complexes, [Mn(salMeDPT)(O 2 CMe)] 1 , [Mn(salMeDPT)Cl]·MeCN 2 , [Mn(salEDPA)] Cl 3 and [Mn(salEDPA)](MeCO 2 ) 4 have been prepared, where the di-Schiff-base salMeDPT and salEDPA were from the (2 + 1) condensation of salicylaldehyde with 4-methyl-4-azaheptane-1,7-diamine and with 4,7-diazadecane-1,10-diamine, respectively. The four complexes have been characterized by elemental analyses and cyclic voltammetry, while complexes 1 - 3 have also been characterized by single-crystal x-ray diffraction, which reveals all the Mn(III) atoms in these complexes adopt slightly compressed octahedra with the Mn-O and Mn-N bond lengths in ranges 1.882(3)-1.890(3) and 2.021(4)-0.546(4) A, respectively. The results of activity assay indicate that complexes 1 - 4 have moderate superoxide dismutase activities.

Complexes of 1,3-bis(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene (bitmb) with silver(I), palladium(II), zinc(II) and cobalt(II) salts have been characterized in the solid state by single-crystal X-ray analysis. The topology of the structures in the solid state, namely finite versus infinite, is found to dependent on the coordination geometry of the metal atoms. For Ag(I) (linear N2 geometry) and Pd(II) (square-planar N4), crystallization with bitmb produces an M2L2 cyclic dimer of composition [Ag2(bitmb)2](PF6)2·2CH3CN (1) or an M2L4 cage complex [Pd2(bitmb)4]Cl4·8H2O·1.5CH3CN (2). For Zn(II) (tetrahedral N2O2) or Co(II) (octahedral N6), crystallization with bitmb produces a 1D zigzag chain network of [Zn(bitmb)(CH3CO2)(C2H5OH)](OH) (3) or an infinite 1D poly-macrocycle chain network [Co(bitmb)2(CH3CN)2](ClO4)2·2C2H5OH (4). It is also found that the conformations of the bitmb ligand are obviously controlled by the coordination number of the central metal ions. When coordinated with silver(I) (coordination number n = 2), palladium(II) (n = 4) or zinc(II) (n = 4), bitmb shows a cis,cis-conformation, but in the case of cobalt(II) (n = 6), bitmb shows a trans,trans-conformation. The results also show that the π⋯π interactions together with the hydrogen bonds co-affect inorganic supramolecular formation.

Six interesting co-ordination polymers [Ag(μ-hmt)(hba)(H2O)] 1, [Ag(μ-hmt)(aba)(H2O)] 2, [Ag2(μ-hmt)2(bca)(H2O)2]·H2O 3, [Ag(μ-hmt)(ina)]·0.5H2O 4, [Ag(μ-hmt)(bsa)] 5, [Ag2(μ-hmt)2(bda)]·4H2O 6 (hmt = hexamethylenetetramine, hba = 4-hydroxybenzoate, aba = 4-aminobenzoate, bca = 4,4′-biphenyldicarboxylate, ina = isonicotinate, bsa = benzenesulfinate, bda = 1,4-butanedioate), have been prepared and structurally characterised. These co-ordination frameworks, all based on the Ag(μ-hmt) chains, exhibit new structural varieties in the Ag–hmt system, such as the chains in 1 and 2, ladders in 3, grids in 4, double-chains in 5, as well as rectangular grids with double-chains in 6. The result shows that the structural variations are mainly dependent upon the nature of the anionic ligands used.

Synthesis of a polydentate ligand comprising imidazole donors, 1,3-bis[(4-methyl-5-imidazol-1-yl)ethylideneamino]propan-2-ol (BIPO), and its ZnII (1), MnII (2), NiII (3) and CuII (4) complexes are reported. Single-crystal structural analysis shows that complex 1 adopts a distorted square-pyramidal coordination geometry with the basal positions occupied by the four nitrogen atoms of a tetradentate BIPO ligand and the apical position by a water molecule, complexes 2 and 3 exhibit elongated octahedral coordination geometries with the axial positions occupied by a pair of aqua molecules, whereas complex 4 exhibits an elongated octahedral geometry with the axial positions occupied by an aqua molecule and a perchlorate oxygen atom. The crystal structures of the four complexes are discussed in relation to the preference of zinc ion in carbonic anhydrase, and suggest that in the presence of nitrogen donor ligands, ZnII has a significant tendency to form a four- or five-coordination. Hydrolysis of 4-nitrophenyl acetate with complexes 1–3 shows that the kobs for complexes 1, 2 and 3 were 2.74×10−2± 0.01, 1.45×10−2± 0.01 and 0.98×10−2± 0.01 M−1s−1, respectively.

The mononuclear complex Fe(II)(mtq)2{P(OCH3)3}2 (Hmtq = 8-Mercaptoquinoline) with mixed N-heterocyclic thiolato and phosphite ligands was synthesized and characterized by X-ray crystallography and cyclic voltammetric measurement. The title complex crystallizes in the triclinic space group P-1 with a = 8.929(4), b = 9.965(3), c = 16.913(11) A, α = 76.21(10), β = 80.89(10), γ= 68.010(10)°, V = 1351.2(11) A3. The Fe(II) atom exhibits an elongated octahedral geometry composed of N2S2P2 donors. The equatorial plane is made up of two cis-oriented N donors from the thiolato ligands and two cis-oriented monodentate P(OCH3)3 ligands. The apical sites are occupied by two trans-oriented S atoms from the mtq− ligands. The thione form is predominant coordination mode of 8-mercaptoquinoline with the N and S donors bound to the Fe(II) to form five-membered chelate rings. The structural feature of the mononuclear Fe(II) complex with mixed phosphite and thiolate ligands is summarized.

A cobalt-thiolato-phosphite complex [Co(o-SC6H4NH2){P(OMe)3}3]PF6 has been prepared and characterized by X-ray crystallography. The complex crystallizes in the triclinic space group $$P\bar 1$$ with a = 10.590(4), b = 11.122(3), c = 13.577(5) A, α = 101.85(1), β = 108.50(1), γ = 101.75(1)°, V = 1420.6(8) A3, and Z = 2. The structure comprises discrete [Co(o-SC6H4NH2){P(OMe)3}3]+ cations and PF 6 − anions where the metal atom is coordinated in a highly distorted square-pyramidal environment by one chelate o-SC6H4NH 2 − (abt) and two P(OMe)3 ligands in the basal positions, and a third P(OMe)3 in the axial site with Co–N,, 1.847(5), Co–S, 2.166(2), Co–P, 2.157(2), 2.147(2), and 2.125(2) A.

The title compound, methyl 2-[4-(3-fur­yl)-6b,10a-dihydr­oxy-3a,7,9,9-tetra­methyl-6,10-dioxo-2,3,3a,6b,7,8,9,10,10a,11-deca­hydro-1aH,4H,6H-benzo[h][1]benzoxireno[3,2,1a-de]isochro­men-8-yl]acetate, C27H32O9, is a new tetra­nor­tri­ter­pen­oid which was isolated for the first time from the seeds of Lansium domesticum Coor. The four six-membered rings adopt chair, boat, envelope and screw-boat conformations. The furan substituent is planar and is attached equatorially to the lactone ring. O—H⋯O hydrogen bonds link the mol­ecules into chains along [100] and adjacent chains are inter­connected by C—H⋯O inter­actions.