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Bismuth-contained therapies are effective in treating gastric ulcer and eliminating Helicobacter pylori (Hp). Anion polysaccharides ligand could reduce the intake of bismuth, and enhance drug efficacy of bismuth compounds. In this study, pectin-bismuth (PB) was prepared and the changes of PB structure in acidic environment were reported for the first time. The structure of PB was characterized by FT-IR, XRD, and TGA, which suggested that combined with bismuth could alter the crystal structure of pectin. XPS confirmed the ionic binding of Bi3+ with carboxyl groups of pectin. The aggregating of PB with different pH level were also investigated, and the influence of pH on PB structure were observed by SEM. Results showed that PB has much larger volume of flocculation in acidic environment compared with bismuth nitrate. Additionally, apparent shear stress (τa) of PB suspension was evaluated. These results revealed the structural characteristics and acid-induced aggregation of pectin-bismuth, and bismuth could aggregate in acidic solution with the gelation of pectin.

A gelling strategy for HP was proposed in this study, ammonium sulfate (AS) as a co-solute could induce the gelling of HP in acidic environment. The solubility and Zeta potential of HP dramatically decreased in AS solution, which indicated AS could promote the aggregation of HP. The rheological results confirmed the gelling of HP (G' G″) with AS: 25-30 wt% and pH ≤ 3.0, and the gel strength is mainly depended on HP rather than AS concentration. Smaller AS crystals (SEM) and reduced T

Moderate alkali de-esterification can change the physicochemical characteristics and thus the functional properties of high methoxyl pectin (HMP). The results revealed that de-esterification could increase negative charges (Zeta potential from -21 to -31 mV), decrease molecular weight (from 448 to 136 kDa) and apparent viscosity of HMP. Homogalacturonan (HG) content decreased (from 62% to 49%) while rhamnogalacturonan Ⅰ (RG-Ⅰ) content increased (from 32% to 46%) after de-esterification. The group characteristics of HMP with different degree of esterification (DE) were similar and no obvious impact was made on degree of crystallinity by alkali de-esterification. A conformation transition of HMP molecule implied by Congo red test were occurred as the DE decreased. With the decrease of DE, the molecular structure of HMP became shorter and smaller, and the entanglement was weaker. The de-esterification caused slight decrease of thermal stability. Alkali de-esterification would weaken the gel property and the emulsifying ability of HMP.

SGNH-type acetyl xylan esterases (AcXEs) play important roles in marine and terrestrial xylan degradation, which are necessary for removing acetyl side groups from xylan. However, only a few cold-adapted AcXEs have been reported, and the underlying mechanisms for their cold adaptation are still unknown because of the lack of structural information. Here, a cold-adapted AcXE, AlAXEase, from the Arctic marine bacterium Arcticibacterium luteifluviistationis SM1504T was characterized. AlAXEase could deacetylate xylooligosaccharides and xylan, which, together with its homologs, indicates a novel SGNH-type carbohydrate esterase family. AlAXEase showed the highest activity at 30 °C and retained over 70% activity at 0 °C but had unusual thermostability with a Tm value of 56 °C. To explain the cold adaption mechanism of AlAXEase, we next solved its crystal structure. AlAXEase has similar noncovalent stabilizing interactions to its mesophilic counterpart at the monomer level and forms stable tetramers in solutions, which may explain its high thermostability. However, a long loop containing the catalytic residues Asp200 and His203 in AlAXEase was found to be flexible because of the reduced stabilizing hydrophobic interactions and increased destabilizing asparagine and lysine residues, leading to a highly flexible active site. Structural and enzyme kinetic analyses combined with molecular dynamics simulations at different temperatures revealed that the flexible catalytic loop contributes to the cold adaptation of AlAXEase by modulating the distance between the catalytic His203 in this loop and the nucleophilic Ser32. This study reveals a new cold adaption strategy adopted by the thermostable AlAXEase, shedding light on the cold adaption mechanisms of AcXEs.

In 25% (v/v) ethanol system, an acid induced pectin gelling mechanism was proposed in this study, which could be used to construct emulsion gel system. FT-IR, GPC, and monosaccharides analysis were used to investigated the structure of pectins. HMP and LMP are different in molecular wight and chain structure, and HMP shows excellent gelling property. Intermolecular interaction of acid/ethanol induced HMP gel was investigated with SDS, Urea, and shifted pH. Those results indicated HMP has larger molecular wight, more neutral sugar side chain, and lower zeta potential than LMP, which facilitates the construction of compact gel network. LMP and HMP emulsions with 25% (v/v) ethanol were prepared and HMP emulsions with different oil volume fractions (Φ 0.2–0.75) exhibit gelling properties. Furthermore, the compact structure of HMP gel is stable during the freeze-thaw cycle which improved the freeze-thaw stability of pectin emulsions.

Pectin is widely distributed in plant cell wall, most of which have limited emulsifying properties. Ethanol could alter the solubility of pectin, and affect its emulsifying properties. No creaming and breaking of emulsion appeared in 21% (v/v) ethanol contained emulsion. This project investigated the influence of ethanol (0%-35%, v/v) on conformation and emulsifying properties of pectin. Results shown that ethanol could reduce the helix conformation and zeta potential of pectin chain, which leading to compact conformation and enhanced interaction among pectin molecules. Although emulsion droplet diameter increased with ethanol content, the most stable emulsion was found in 21% (v/v) ethanol. CLSM also indicated over-aggregated pectin have a poor adsorption capacity on the interface of O/W. All results manifested the emulsifying properties of pectin can be improved by 21% (v/v) ethanol. This study provides a new strategy to improve the emulsifying property of pectin by changing its conformation.

Pectin-rich dietary fibers were prepared from citrus peel through alkaline hydrogen peroxide treatment (AHP-CF) or homogenization treatment (H-CF). Structural and physicochemical properties of the citrus fibers were evaluated and compared with a commercial one (Fiberstar). Results showed that pectin content of citrus fibers (CF) increased from 15.23% to 21.52% and 26.79% after AHP and homogenization treatment. AHP-CF had the highest water-holding capacity (WHC) (21.32 g/g), water-swelling capacity (WSC) (32.70 mL/g) and cation exchange capacity (CEC) (1.02 Meq/g) among the fibers. SEM results showed porous or wrinkled surface of the treated CFs. XRD and TG analysis indicated that AHP treatment increased the crystallinity and thermal stability of CF while homogenization treatment was the opposite. Besides, H-CF had similar chemical component, oil-holding capacity and CEC with Fiberstar but higher WHC, WSC and thermal stability. These results suggested that AHP-CF and H-CF might be suitable to be an additive used in functional food.

The apoptosis of myoblast in response to excessive cyclic stretch is crucial in adaptive construction of skeletal muscles in orthopedic functional therapy. Mitochondria signaling pathway is the central links in the execution of the intrinsic apoptotic cascade, but its molecular mechanism in stretch-induced apoptosis in myoblasts remains incompletely understood. The aim of this study was to investigate the mechanobiological roles of caspase-9 and Apoptosis Inducing Factor (AIF), two important components in mitochondrial pathway, in stretch-induced apoptosis of myoblast. Hoechst 33258 was used to observe apoptotic cells morphologically and flow cytometry to analyze apoptosis rate of myoblasts. Protein and mRNA of caspase-9 and AIF were detected by Western blotting and RT-PCR. Furthermore, caspase-9 specific inhibitor z-LEHD-fmk was applied to clear the mechanism of caspase-9 pathway in stretch-induced apoptosis. We found that apoptotic rate induced by cyclic stretch increased in a time-dependent manner, and the same tendency of mRNA and protein of caspase-9 and AIF. Caspase-9 inhibition reduced stretch-induced apoptosis, but had no effect on expression of AIF. We concluded that caspase-9 and AIF played an important role in stretch-induced apoptosis in myoblast, and AIF was involved in the process in a caspase-9 independent way. J. Cell. Biochem. 118: 829-838, 2017. © 2016 Wiley Periodicals, Inc.

OBJECTIVES To explore the association among Arg(972) insulin receptor substrate-1 (IRS-1), hypertension, insulin resistance, and plasma levels of endothelial nitric oxide synthase (eNOS) and endothelin-1 (ET-1). METHODS A total of 1030 patients, including 521 healthy controls, 142 patients with both primary hypertension and insulin resistance, 184 patients with primary hypertension but no insulin resistance, and 183 patients with insulin resistance but no hypertension were genotyped for the Arg(972) IRS-1 polymorphism. Serum levels of ET-1 and eNOS were determined by ELISA. Shear stress was applied to human umbilical vein endothelial cells (HUVECs) overexpressing wild type IRS-1 or Arg(972) IRS-1, and the mRNA and secreted protein levels of ET-1 were measured by real-time RT-PCR and ELISA, respectively. RESULTS There was no significant difference in allelic frequency between patients with and without primary hypertension or insulin resistance, in the hypertensives, heterozygous Arg(972) IRS-1 carriers had significantly higher plasma ET-1 levels and blood pressure (BP) than the homozygous carriers. Although shear stress decreased ET-1 expression in control HUVECs as well as cells transfected with wild type Arg(972) IRS-1, it increased the mRNA dose-dependently and secreted protein levels of ET-1 in cells transfected with Arg(972) IRS-1. CONCLUSIONS Based on both in-vivo and in-vitro data, we have shown a potential causal association between Arg(972) IRS-1 and elevated plasma ET-1 level in hypertensives, which may account for the aggravated hypertension observed in hypertensives with heterozygous Arg(972) IRS-1. This study for the first time provides insights into the role of Arg(972) IRS-1 in hypertension.

Wetland is one of the most diverse ecosystem and important habitats. However, degradation and loss of wetlands increased with anthropologic factors. Thus, the research of wetland restoration has become the emphasis and imperative issue. Water plays an important role in ecological evolution of the wetlands, and water requirement is a key step for water resource management of wetland restoration engineering. This research deals with the analysis of water requirement for wetland restoration engineering in a case study in Bohai Bay. The results show that the total water requirement in the study area are (0.18~0.28)×109m3, (0.54~0.81)×109m3, (1.21~1.41)×109m3 to reach the basic objective, moderate objective and perfect objective, respectively.

Fenton oxidation and coagulation-flocculation-sedimentation (CFS) were both effective in removing many organic constituents of the biotreated coking plant effluent before the final treatment in an activated carbon adsorber. Fenton oxidation broke down most persistent organic pollutants and complex cyanides present in the feed stream and caused the eventual biodegradation of the organic residues in the adsorber. The results of Fenton oxidation followed by adsorption and biodegradation in two biological activated carbon (BAC) adsorbers show that the combined treatment consistently produced a high quality final effluent of50mg/L in COD(Cr) and0.5mg/L in total cyanide during the 70-d study without replacing any activated carbon. The BAC function of the adsorber substantially reduced the need for replacing activated carbon making the combined Fenton oxidation-BAC treatment process a cost effective treatment process to recycle the final effluent for many beneficial reuses while meeting the much more stringent discharge limits of the future.

A survey of yellowfin tuna, Thunnus albacares, fishing ground was carried out on board of the Chinese longliners from September 15 to December 12, 2005 in the tropical high seas of the Indian Ocean. The depth at which each yellowfin tuna was hooked was estimated using a stepwise regression analysis of theoretical hook depth and observed average hook depth measured using a temperature depth recorder. Water temperature, salinity, chlorophyll a, dissolved oxygen and thermocline, which are important variables influencing yellowfin tuna habitats, were measured in the survey. Catch rates of yellowfin tuna were then analyzed with respect to depth, temperature, salinity, chlorophyll a, dissolved oxygen and thermocline. We suggest that the optimum ranges of swimming depth, water temperature, chlorophyll a and dissolved oxygen concentration for yellowfin tuna are 100.0–179.9 m, 15.0–17.9°C, 0.090–0.099 μg L−1, 2.50–2.99 mg L−1, respectively; that salinity has less influence on the vertical distribution of adult yellowfin tuna; and that yellowfin tuna are mainly distributed within the thermocline in the high seas of the Indian Ocean. Our results match the yellowfin tuna’s vulnerability to deep longline fishing gear well.

A series of follow-up investigations were performed to produce data for improving the four-indicator carbon selection method that we developed to identify high-potential activated carbons effective for removing specific organic water pollutants. The carbon's pore structure and surface chemistry are dependent on the raw material and the activation process. Coconut carbons have relatively more small pores than large pores; coal and apricot nutshell/walnut shell fruit carbons have the desirable pore structures for removing adsorbates of all sizes. Chemical activation, excessive activation, and/or thermal reactivation enlarge small pores, resulting in reduced phenol number and higher tannic acid number. Activated carbon's phenol, iodine, methylene blue, and tannic acid numbers are convenient indicators of its surface area and pore volume of pore diameters 28 A, respectively. The phenol number of a carbon is also a good indicator of its surface acidity of oxygen-containing organic functional groups that affect the adsorptive capacity for aromatic and other small polar organics. The tannic acid number is an indicator of carbon's capacity for large, high-molecular-weight natural organic precursors of disinfection by-products in water treatment. The experimental results for removing nitrobenzene, methyl-tert-butyl ether, 4,4-bisphenol, humic acid, and the organic constituents of a biologically treated coking-plant effluent have demonstrated the effectiveness of this capacity–indicator-based method of carbon selection. A comprehensive table of iodine, phenol, methylene blue, and tannic numbers of common activated carbons is a useful database to environmental professionals for selecting few high-potential activated carbons to be evaluated in an efficient water/wastewater treatability study. © 2007 American Institute of Chemical Engineers Environ Prog, 2007

A simple and cost-effective method for conducting adsorption breakthrough experiments in a microsize carbon column is proposed; it is much faster than the conventional methods. Relative to the existing microcolumn rapid breakthrough (MCRB) methods, this method employs simplified procedure, low cost and readily available pump, sampler, and piping and fittings to allow its practice in an ordinary environmental laboratory. The efficient MCRB method may be employed to identify the best granular activated carbon, to verify its treatment effectiveness, and to estimate its capacity utilization rate and the adsorption treatment cost. The effects of particle size and empty bed contact time on MCRB test results were determined. The validity and benefits of this MCRB method were demonstrated by the adsorption breakthrough data for phenol, red dye X3B, tannic acid, MTBE, 2,4-dichrophenol, and the organic pollutants in a biologically treated coking plant effluent. © 2007 American Institute of Chemical Engineers Environ Prog, 2007

To explore the stem cell surface markers expressed in human dental pulp stem cells which were selected and isolated by magnetic beads.Human dental pulp cells (hDPCs) were separated and cultured from dental pulp of healthy third molars for orthodontic purpose. HDPSCs were isolated from cultured hDPCs by magnetic-activated cell sorting's (MACS) indirect magnetic cell labeling and positive selection strategy with antibody STRO-1 in the 2nd generation. Then the stem cell surface markers (CD73, CD90, CD105, CD166 and STRO-1) were respectively detected in 3, 4, 5, 6, 7 and 8 generation of dental pulp stem cells. HDPSCs were induced to differentiation by adipogenic medium and osteogenic medium in the 3rd generation. Adipogenic differentiation was assessed by oil red O staining in day 21, and osteogenic differentiation was assessed by alizarin red staining in day 21.HDPSCs could differentiate into adipocyte and osteoblasts. Oil red O staining and alizarin red staining were positively expressed after induction of HDPSCs. STRO-1's expression was decreased with the increase of generation. The expressions of CD73, CD90, CD105 and CD166 were relatively stable.The expression of STRO-1 is declined with the increase of generation, and the expressions of CD73, CD90, CD105 and CD166 are relatively stable with the changes of generation. Supported by National Natural Science Foundation of China (81070826/81371143) and Shanghai Rising-Star Program (12QH1401400).

To establish an immortalized human dental pulp stem cell line used for basic and clinical research of oral science.Human telomerase reverse transcriptase (hTERT) cDNA was transferred into human dental pulp stem cells (hDPSCs) by lentivirus. The resultant stable clones reproduced successively and the expression of hTERT was identified.The hTERT gene was transferred into human dental pulp stem cells successfully. The transformed cells expressed telomerase activity and divided vigorously. p35 had been obtained so far.The hDPSCs can be immortalized by transferring exogenous hTERT gene to constitute telomerase activity.

To complement the activated methyl cycle (AMC) pathway at an AI-2 defect background in Streptococcus mutans (S. mutans) luxS null strain.A sahH gene was amplified from Pseudomonas aeruginosa and introduced into the S. mutans luxS null strain to complement the methyl-metabolic disruption at an AI-2 defect background. Western blot, reverse-transcription PCR and AI-2 bioassay were performed to confirm the heterogenous expression of SahH in S. mutans luxS null strain. The data was statistically analyzed by SAS8.0 software package.LuxS and SahH were detected to express in Escherichia coli BL21 as well as their mRNA were confirmed to be successfully transcribed in S. mutans luxS null strain. AI-2 production was found in wide type S. mutans and its luxS-introduced luxS null strain but not found in the luxS null strain and its sahH and empty plasmid-introduced strains.A new S. mutans derivative with the AMC pathway complements while the AI-2 defect is constructed.

To investigate the values of extravascular lung water and preload parameters of weaning from mechanical ventilation on patients with septic shock.A prospective study was conducted. A total of 52 septic shock patients with mechanical ventilation were enrolled from January 2010 to July 2012. All patients were treated and monitored by pulse induced continuous cardiac output (PiCCO) till they reached weaning criteria, and then spontaneous breathing trial (SBT), weaning, and extubation were performed in turn. The enrolled patients were divided into two groups including successful weaning group (n=38) and weaning failure group (n=14) according to clinical manifestations during 48 hours after weaning. Extravascular lung water index (EVLWI), preload parameters such as global end diastolic volume index (GEDVI) and intra-thoracic blood volume index (ITBVI), pulmonary vascular permeability index (PVPI) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were compared at the time before weaning, 0.5 hour after weaning, 0.5 hour after extubation, and time of weaning failure or 48 hours after weaning. The patients in weaning failure group were sub-divided into high PVPI group (PVPI≥1.5 ml/m(2)) and low PVPI group (PVPI1.5 ml/m(2)), the NT-proBNP and pulmonary blood volume (PBV) were compared between two groups.Before weaning, there was no statistical difference in NT-proBNP, volume parameters and EVLWI between two groups. EVLWI, GEDVI, ITBVI, PVPI and log NT-proBNP were gradually increased after weaning and extubation in two groups. The EVLWI, PVPI and log NT-proBNP were significantly higher at end point of observation in weaning failure group compared with those in successful weaning group (EVLWI: 12.81±2.13 ml/kg vs. 8.48±1.53 ml/kg, PVPI: 2.79±1.29 ml/m(2) vs. 2.19±0.94 ml/m(2), log NT-proBNP: 3.72±0.35 vs. 3.44±0.28, P0.05 or P0.01). GEDVI, ITBVI at 0.5 hour after weaning and end point of observation in weaning failure group were significantly higher than those in successful weaning group (0.5 hour after extubation: GEDVI 986.29±166.44 ml/m(2) vs. 856.47±149.15 ml/m(2), ITBVI: 1171.07±167.03 ml/m(2) vs. 1045.79±146.09 ml/m(2); end point of observation: GEDVI 957.00±67.25 ml/m(2) vs. 816.86±27.58 ml/m(2), ITBVI: 1184.29±209.68 ml/m(2) vs. 993.79±168.90 ml/m(2), P0.05 or P0.01). Sub-analysis showed that in weaning failure group, higher log NT-proBNP and PBV were found in patients with low PVPI compared with those with high PVPI (log NT-proBNP: 4.02±0.11 vs. 3.71±0.23, PBV: 507.19±25.72 ml vs. 347.85±47.52 ml, P0.05 and P0.01).Increased EVLW is the reason of pulmonary edema caused by weaning in septic shock patients, to which both hydrostatic and pulmonary permeability may contribute, and the latter could be more important. Monitoring preload parameters could help distinguish the mechanism of pulmonary edema after weaning, which may be useful in treatment.

To explore the relationship between plasma N-terminal-pro-brain natriuretic peptide (NT-proBNP) levels of patients before weaning and outcome of weaning from mechanical ventilation (MV) in patients.A total of 126 intensive care unit (ICU) patients with MV were enrolled from August 2008 to December 2009, and the cause composition was recorded. Plasma NT-proBNP levels were measured in patients with MV, in whom the clinical data had fulfilled the criteria for weaning from MV, spontaneous breathing trial, weaning and extubation were performed successively. The enrolled patients were divided into two groups namely success group and failure group according to weaning outcome within 48-hour. The plasma NT-proBNP levels in two groups were compared, and receiver operating characteristic (ROC) curve for predicted weaning outcome was plotted to find the cut-off point value of NT-proBNP.The major causes of MV were pulmonary infection (33.3%) and surgical operations (30.2%), and heart failure accounted for only 11.9%. The plasma NT-proBNP levels before weaning were negatively correlated with the consequences of weaning. The plasma NT-proBNP levels in failure group (n=38) were significantly higher than those in success group (n=88, lg NT-proBNP: 3.97+/-0.48 vs. 2.99+/-0.67 ,P0.05). The NT-proBNP area under ROC curve was 0.875+/-0.043 [95% confidence interval (95% CI) was 0.792-0.959]. The cut-off point value which could be used to predict the outcome of weaning was 3 914.5 ng/L. The sensitivity and specificity of the cut-off point value were 78.3% and 91.1%, respectively.Irrespective of the causes of institution of MV, the cardiac function must be considered as an important factor in affecting the outcome of weaning. The plasma NT-proBNP level of 3 914.5 ng/L can be used to predict weaning outcome. The cardiac function should be improved to a point within the range of cut-off point value in order to improve the success rate of weaning.