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In this study, a new method for the determination of fipronil and its three metabolites in environmental water samples was developed based on meltblown nonwoven fabric solid-phase extraction combined with gas chromatography-electron capture detection. As the core material of medical masks, meltblown nonwoven fabric is made of polypropylene superfine fibers which are randomly distributed and bonded together with a relatively large specific surface area and good permeability. Polypropylene as a high molecular hydrocarbon-based polymer has the characteristics of good hydrophobicity and lipophilicity, which can be applied for the separation and enrichment of hydrophobic substances in food, environment, and biological samples. The meltblown nonwoven fabric is soft and can fill the solid-phase extraction cartridge tightly. This aspect also makes it suitable to be used as an ideal solid-phase extraction sorbent. A series of parameters influencing the extraction efficiency were investigated, and under the optimized conditions, fipronil and its three metabolites had a good linear relationship in the range of 0.2-100 μg/L with a correlation coefficient R

Rice black-streaked dwarf virus disease (RBSDVD) and southern rice black-streaked dwarf virus disease (SRBSDVD) are the most destructive viral diseases in rice. Progress is limited in breeding due to lack of resistance resource and inadequate knowledge on the underlying functional gene. Using genome-wide association study (GWAS), linkage disequilibrium (LD) decay analyses, RNA-sequencing, and genome editing, we identified a highly RBSDVD-resistant variety and its first functional gene. A highly RBSDVD-resistant variety W44 was identified through extensive evaluation of a diverse international rice panel. Seventeen quantitative trait loci (QTLs) were identified among which qRBSDV6-1 had the largest phenotypic effect. It was finely mapped to a 0.8-1.2 Mb region on chromosome 6, with 62 annotated genes. Analysis of the candidate genes underlying qRBSDV6-1 showed high expression of aspartic proteinase 47 (OsAP47) in a susceptible variety, W122, and a low resistance variety, W44. OsAP47 overexpressing lines exhibited significantly reduced resistance, while the knockout mutants exhibited significantly reduced SRBSDVD and RBSDVD severity. Furthermore, the resistant allele Hap1 of OsAP47 is almost exclusive to Indica, but rare in Japonica. Results suggest that OsAP47 knockout by editing is effective for improving RBSDVD and SRBSDVD resistance. This study provides genetic information for breeding resistant cultivars.

Tumor-induced osteomalacia TIO is a rare paraneoplastic syndrome caused by excessive production of fibroblast growth factor 23 FGF23 by a tumor. Previous studies have revealed generalized mineralization defects and low areal bone mineral density aBMD in TIO. However, data on the bone microarchitecture in TIO are limited. In this study, we evaluated the microarchitecture in the peripheral distal radius and tibia and axial lumbar spine skeleton using high-resolution peripheral quantitative computed tomography HR-pQCT and trabecular bone score TBS and investigated related factors in a large cohort of Chinese patients with TIO. A total of 186 patients with TIO who had undergone dual-energy X-ray absorptiometry DXA or HR-pQCT scans were enrolled. Compared with age-, sex- and BMI-matched healthy controls, TIO patients n=113 had lower vBMD, damaged microstructure and reduced bone strength in the peripheral skeleton, especially at the tibia. The average TBS obtained from 173 patients was 1.15 ± 0.16. The proportion of patients with abnormal TBS

Xanthomonadins are yellow pigments that are produced by the phytopathogen Xanthomonas campestris pv. campestris (Xcc). A pig cluster is responsible for xanthomonadin biosynthesis. Previously, Xcc4014 of the cluster was characterized as a bifunctional chorismatase that produces 3-hydroxybenzoic acid (3-HBA) and 4-HBA. In this study, genetic analysis identified 11 genes within the pig cluster to be essential for xanthomonadin biosynthesis. Biochemical and bioinformatics analysis suggest that xanthomonadins are synthesized via an unusual type II polyketide synthase pathway. Heterologous expression of the pig cluster in non-xanthomonadin-producing Pseudomonas aeruginosa strain resulted in the synthesis of chlorinated xanthomonadin-like pigments. Further analysis showed that xanC encodes an acyl carrier protein (ACP) while xanA2 encodes a ATP-dependent 3-HBA:ACP ligase. Both of them act together to catalyse the formation of 3-HBA-S-ACP from 3-HBA to initiate xanthomonadin biosynthesis. Finally, we showed that xanH encodes a FabG-like enzyme and xanK encodes a novel glycosyltransferase. Both xanH and xanK are not only required for xanthomonadin biosynthesis, but also required for the balanced biosynthesis of extracellular polysaccharides and DSF-family quorum sensing signals. These findings provide us with a better understanding of xanthomonadin biosynthetic mechanisms and directly demonstrate the presence of extensive cross-talk among xanthomonadin biosynthetic pathways and other metabolic pathways.

The rapid development of fast, powerful, and affordable computer technology has provided educators options to introduce innovations in teaching and learning process. The purpose of this study is to investigate the effect of computational simulations on students' understanding of marine mooring line tension in ocean engineering course. Instructional strategies need to incorporate mathematical and computational knowledge into their practice project so that students can use its core concepts to solve interdisciplinary problems. By writing students own Matlab program, students will demonstrate the effect of mathematical and computational tools on the analysis of ocean structural dynamics. The effectiveness of instructional methods by investigating learning gains, instructional effect, and student perceptions about the course are evaluated. Through the teaching practice, students significantly increase their understanding of ocean engineering concepts.

Introduction Ilex pubescens Hook et Arn mainly contains triterpenoids that possess antithrombotic, anti-inflammatory and analgesic effects. Quantitative and qualitative analyses of the triterpenoids in I. pubescens can be useful for determining the authenticity and quality of raw materials and guiding its clinical preparation. Objectives To establish a method for rapid and comprehensive analysis of triterpenoids in I. pubescens using ultra-high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight-mass spectrometry (UPLC-ESI-QTOF-MS), which will also be applied to evaluate the contents of nine triterpenoids among root, root heartwood and root bark of I. pubescens to judge the value of the root bark to avoid wastage. Methods UPLC-ESI-QTOF-MS data from the extracts of I. pubescens in negative mode were analysed using Peakview and Masterview software that provided molecular weight, mass errors, isotope pattern fit and MS/MS fragments for the identification of triterpenoids. The quantification of nine investigated compounds of I. pubescens was accomplished using MultiQuant software. Results A total of 33 triterpenoids, five phenolic acids, two lignans and a flavonol were characterised in only 14 min. The total content of the nine compounds in the root bark was generally slightly higher than that of the root and root heartwood, which has not been reported before. Conclusion The developed UPLC-ESI-QTOF-MS method was proven to be rapid and comprehensive for simultaneous qualitative and quantitative analyses of the characteristic triterpenoids in I. pubescens. The results may provide a basis for holistic quality control and metabolic studies of I. pubescens, as well as serve as a reference for the analysis of other Ilex plants. Copyright © 2017 John Wiley & Sons, Ltd.

Soybeans contain oil bodies (OBs) that encapsulate triacylglycerols (TAGs) with a phospholipid monolayer carrying scattered proteins. In nature, soybean OBs can form natural emulsions in aqueous media and may serve as natural, minimally processed, stable, and pre-emulsified oil for addition into appropriate food systems. In this study, OBs were obtained by aqueous extraction from the mature seeds of 2 soybean crop cultivars, high-fat soybean and low-fat soybeans. The compositions of the extracted OBs were analyzed during storage at room temperature up to 14 d (pH = 7). The oxidative stability of these OBs, stored at 60 °C, was evaluated by measuring the presence of primary (lipid hydroperoxides) and secondary lipid oxidation products (malondialdehyde) by determining the standard peroxide value (PV) and thiobarbituric acid-reactive substances (TBARS) value. During storage, the contents of unsaturated fatty acids, phospholipids, and tocopherols declined in both OBs, while their mean particle diameters (d32) and ζ-potentials increased. The changes in PV and TBARS values exhibited a similar trend for both OBs, but the OBs from low-fat soybeans had significantly lower PV and higher TBARS values than the OBs from high-fat soybean cultivars (P < 0.05). Overall, the OBs from both soybean cultivars had good stability during storage.

Summary Phenazines are important secondary metabolites that have been found to affect a broad spectrum of organisms. Two almost identical gene clusters phz1 and phz2 are responsible for phenazines biosynthesis in the rhizobacterium Pseudomonas aeruginosa PA1201. Here, we show that the transcriptional regulator RsaL is a potent repressor of phenazine-1-carboxylic acid (PCA) biosynthesis. RsaL negatively regulates phz1 expression and positively regulates phz2 expression via multiple mechanisms. First, RsaL binds to a 25-bp DNA region within the phz1 promoter to directly repress phz1 expression. Second, RsaL indirectly regulates the expression of both phz clusters by decreasing the activity of the las and pqs quorum sensing (QS) systems, and by promoting the rhl QS system. Finally, RsaL represses phz1 expression through the downstream transcriptional regulator CdpR. RsaL directly binds to the promoter region of cdpR to positively regulate its expression, and subsequently CdpR regulates phz1 expression in a negative manner. We also show that RsaL represents a new mechanism for the turnover of the QS signal molecule N-3-oxododecanoyl-homoserine lactone (3-oxo-C12-HSL). Overall, this study elucidates RsaL control of phenazines biosynthesis and indicates that a PA1201 strain harboring deletions in both the rsaL and cdpR genes could be used to improve the industrial production of PCA.

Zeolitic imidazolate frameworks have positive surface charges and high adsorption capabilities. In this work, zeolitic imidazolate frameworks-8 and negatively charged magnetic nanoparticles were self-assembled by electrostatic attraction under sonication. The extraction performance of the synthesized hybrid material was evaluated by using it as a magnetic adsorbent for the enrichment of triazine herbicides in various sample matrices prior to analysis using ultrafast liquid chromatography. The main parameters, that is, extraction time, adsorbent dosage, salt concentration, and desorption conditions, were evaluated. Under the optimum conditions, good linear responses from 2.5 to 200 ng/mL for atrazine (simazine) and 1 to 200 ng/mL for prometryn (ametryn), with correlation coefficients (R2 ) higher than 0.9992 were obtained. The detection limits of the method (S/N = 3) were 0.18-0.72 ng/mL. The proposed method was successfully used to determine triazine herbicides in six samples, namely, apple, pear, strawberry, pakchoi, lettuce, and water. The amounts of simazine in all the fruit and vegetable samples were 10.8-25.2 ng/mL. The recoveries of all the analytes were 88.0-101.9%, with relative standard deviations of less than 8.8%.

BACKGROUND Vascular endothelial growth factor (VEGF) plays an important role in the formation of capillary blood vessels. The purpose of this study was to evaluate the inhibitory effect of VEGF-targeted paclitaxel (PTX)-loaded liposome microbubbles (VTPLLMs) on the proliferation of human epidermoid (Hep-2) laryngeal squamous cell carcinoma (SCC). METHODS Six groups were randomly divided. The inhibitory effects on Hep-2 proliferation were assessed by a methylthiazol tetrazolium (MTT) method. The cell cycle distributions were investigated by flow cytometry. The expression variations of VEGF and caspase-3 were compared by Western blotting. RESULTS Proliferation of Hep-2 in the VTPLLM+ultrasound group was significantly inhibited, and flow cytometry showed that the Hep-2 cells were significantly blocked at stage G2/M compared with other groups. Moreover, Western blotting showed VEGF expression was downregulated and caspase-3 expression was upregulated. CONCLUSION VTPLLMs can efficiently inhibit tumor cell proliferation and outperform nontargeted microbubbles or PTX. © 2017 Wiley Periodicals, Inc. Head Neck 39: 656-661, 2017.

In the present study, the relationships of soybean 11S globulin content, thermal properties, and retrogradation properties of nonwaxy maize starch in starch–globulin mixtures were investigated by differential scanning calorimetry. The onset and peak temperatures of maize starch were positively related to soybean 11S globulin content, whereas the thermal enthalpy was negatively related to it. However, the onset temperature, peak temperature, and thermal enthalpy of soybean 11S globulin were negatively related to maize starch content of mixtures. On the other hand, the onset and peak temperatures of retrograded maize starch were positively related to soybean 11S globulin content, whereas the retrogradation enthalpy was negatively related to it during storage. Therefore, adding soybean 11S globulin was an effective method to control maize starch gelatinization and retrogradation properties, which will be helpful for the food industry to produce high-quality products based on starch and soybean protein.

Summary Molecules of the diffusible signal factor (DSF)-family are a class of quorum sensing (QS) signals used by the phytopathogens Xanthomonas. Studies during the last decade have outlined how Xanthomonas cells enter the QS phase. However, information on the mechanism underlying its exit from the QS phase is limited. RpfB has recently been reported as a fatty acyl-CoA ligase (FCL) that activates a wide range of fatty acids to their CoA esters in vitro. Here, we establish an improved quantification assay for DSF-family signals using liquid chromatography-mass spectrometry in X. campestris pv. campestris (Xcc). We first demonstrated that RpfB represents a naturally occurring DSF-family signal turnover system. RpfB effectively turns over DSF-family signals DSF and BDSF in vivo. RpfB FCL enzymatic activity is required for DSF and BDSF turnover. Deletion of rpfB slightly increased Xcc virulence in the Chinese radish and overexpression of rpfB significantly decreased virulence. We further showed that the expression of rpfB is growth phase-dependent, and its expression is significantly enhanced when Xcc cells enter the stationary phase. DSF regulates rpfB expression in a concentration-dependent manner. rpfB expression is also negatively regulated by the DSF signalling components RpfC, RpfG and Clp. The global transcription factor Clp directly binds to the AATGC-tgctgc-GCATC motif in the promoter region of rpfB to repress its expression. Finally, RpfB-dependent signal turnover system was detected in a wide range of bacterial species, suggesting that it is a conserved mechanism.

The utilization of interactive computer to teaching and learning Biot Poroelasticity Modeling is becoming an important aspect of the implementation of a more advanced approach to teaching in Civil Engineering. As part of the learning method, an interactive computer-based instructional assistance is specifically developed to help students to build, run, and analyze the output from a commercially software- COMSOL for Biot poroelasticity equations. The Biot poroelasticity equations and constitutive relation of fluid flow are input as partial differential equations into a customizable finite element software package. Several numerical simulations such as vertical effective stress and pore pressure, are presented to illustrate the validity and usefulness of the fully coupled approach, which is verified in the Biot poroelasticity modeling formulation. The assessment of instructor tools include: homework, term project, small group discussions, which assists to assess the student's degree of understanding for Biot poroelasticity theory. The survey finds that most students feel they could complete the project with minimum supervision, and have a basic understanding of variation of pore pressure as a result of the activity. On the other hand, almost of students feel that the COMSOL software aid helpful and easy to follow. © 2015 Wiley Periodicals, Inc. Comput. Appl. Eng. Educ. 9999:1–11, 2015; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21662

The low-Sr content (generally < 100 μg g-1) in clinopyroxene from peridotite makes accurate Sr isotopic determination by LA-MC-ICP-MS a challenge. The effects of adding N2 to the sample gas and using a guard electrode (GE) on instrumental sensitivity for Sr isotopic determination by LA-MC-ICP-MS were investigated. Results revealed no significant sensitivity enhancement of Sr by adding N2 to the ICP. Although using a GE led to a two-fold sensitivity enhancement, it significantly increased the yield of polyatomic ion interferences of Ca-related ions and TiAr+ on Sr isotopes. Applying the method established in this work, 87Sr/86Sr ratios (Rb/Sr < 0.14) of natural clinopyroxene from mantle and silicate glasses were accurately measured with similar measurement repeatability (0.0009-0.00006, 2SE) to previous studies but using a smaller spot size of 120 μm and low-to-moderate Sr content (30-518 μg g-1). The measurement reproducibility was 0.0004 (2s, n = 33) for a sample with 100 μg g-1 Sr. Destruction of the crystal structure by sample fusion showed no effect on Sr isotopic determination. Synthesised glasses with major element compositions similar to natural clinopyroxene have the potential to be adopted as reference materials for Sr isotopic determination by LA-MC-ICP-MS.

Objective This study aimed to evaluate the efficacy including the patients' response rates to infliximab (IFX) therapy, relapse rates after IFX-induced clinical remission, and the safety of IFX in Chinese patients with ulcerative colitis (UC) from a single center in southern China and to identify the risk factors associated with disease relapse. Methods Medical records of Chinese UC patients who were diagnosed and received at least two infusions of IFX at Nanfang Hospital, Southern Medical University from July 2010 to February 2013 were retrospectively reviewed. Primary outcomes were regarded as the clinical response and relapse rates during 30 weeks after the initiation of the therapy. Overall adverse events and relapse-related risk factors were also evaluated. Results A total of 24 UC patients was finally included. The clinical response and remission rates were 83.3% and 50.0% at week 2, 91.3% and 73.9% at week 6 and 84.6% and 61.5% by week 30. Relapse after IFX-induced clinical remission was initiated at the fourth infusion. The relapse rate was 29.4% at week 14, 25.0% at week 22 and 20.0% at week 30, respectively. After 30 weeks only 33.3% remained on maintenance therapy. IFX-associated adverse events occurred in 29.2% of patients, with most being mild and transient. Patients with distal or extensive colitis were at a higher risk of relapse than those with ulcerative proctitis. Conclusions IFX is effective and safe in treating Chinese UC patients, although long-term remission is hard to achieve. Distal or extensive colitis may be an independent predictor of disease relapse.

Background The axis inhibition protein 2 (AXIN2) is an important regulator of β-catenin degradation in the Wnt pathway, which plays a key role in craniofacial morphogenesis. The goal of this study was to investigate the potential relationship between AXIN2 polymorphisms and the risks of non-syndromic orofacial clefts (NSOC) in a Chinese Han population. Methods Four polymorphisms of AXIN2 (rs2240307, rs11867417, rs2240308, and rs7591) were selected to perform a case–control study with 599 NSOC cases and 602 healthy individuals from a Chinese Han population. The single nucleotide polymorphisms (SNPs) were genotyped on basis of double ligation and multiplex fluorescence PCR. Results Weak associations were found between these four SNPs and the risk of NSOC. Further stratified analysis showed that the overall genotype frequencies of rs2240307 were different between the cleft palate only (CPO) group and the control group (P = 0.048), and GG genotype markedly contributed to the susceptibility to CPO (OR = 3.22, 95% CI = 1.13–9.18). The similar effect was also observed on GA/AA genotype compared with GG homozygote (OR = 0.30, 95% CI = 0.11–0.84). The results of LD analysis between each pair of SNPs revealed that two SNPs (rs11867417 and rs7591) were in a LD block (r2 > 0.8). But no statistically significant was found between cases and controls from haplotype analysis in these two loci. Conclusions The borderline results gave us a hint that rs2240307 contributed to the susceptibility to CPO in a Chinese Han population, which was conductive to improving our awareness of the causes of NSOC.

Polyethylene glycol (PEG) is a short-term (41 days) potential vitreous substitute and is too short for an ideal vitreous substitute. Previously, a foldable capsular vitreous body (FCVB) was designed to mimic vitreous function. The aim of this study is to evaluate whether PEG injected into FCVB can serve as a long-term vitreous substitute. In vitro study, a concentration of 5% (w/v) PEG sols showed natural-like mechanical and optical properties in terms of pH, density, light transmittance, refractive index, interfacial tension, viscosity, rheology, and cytotoxicity. Then in vivo tests, 30 rabbits received standard pars plana vitrectomy, of which 12 eyes were implanted with PEG injected into FCVB, nine eyes were injected with PEG sols alone, and nine others were injected with balance salt solution as control. A clinical evaluation of the anterior segment, fundus, and intraocular pressure was measured pre- and postoperatively up to 180 days, which showed that FCVBs had good retina supporting function, except for a higher incidence of cataracts. Gross pathology, hematoxylin and eosin, and terminal deoxynucleotidyl transferase dUTP nick end labeling staining analysis also showed that FCVBs had good biocompatibility, and that all quadrants of the capsular wall fitted well with the retina. This study demonstrated that PEG injected into FCVB can serve as a long-term vitreous substitute and has potential clinical use.

Aim miR-145 is a candidate tumor suppressor miRNA. However, it is unknown whether miR-145 is involved in the invasion of hepatocellular carcinoma (HCC). Therefore, we aimed to explore the effect and mechanism of miR-145 in the control of HCC cell invasion. Methods HCC cell invasion was evaluated by transwell assays after transfection with pre-miR-145 or anti-miR-145. A luciferase reporter assay was used to determine whether a disintegrin and metalloprotease 17 (ADAM17) were a target of miR-145. The levels of miR-145 and ADAM17 mRNA were detected by a real-time polymerase chain reaction assay, and the level of ADAM17 protein was measured by western blot analysis. Pearson's correlation test was used to assess the correlation between ADAM17 mRNA expression and miR-145 expression in 20 HCC tissue samples. Results miR-145 was significantly downregulated in HCC tissues and cell lines. The loss of miR-145 expression was associated with the tumor–node–metastasis stage, vascular invasion and intrahepatic metastasis. The overexpression of miR-145 was able to suppress tumor MHCC-97H cell invasion, whereas the knockdown of miR-145 expression induced SMMC-7721 cell invasion. We demonstrated that miR-145 bound directly to the 3′-untranslated region of ADAM17 and inhibited the expression of ADAM17. The knockdown of ADAM17 in SMMC-7721 cells could partially reverse the effects of anti-miR-145. miR-145 expression was inversely associated with ADAM17 expression in 20 HCC tissue specimens. Conclusion Our findings indicate that miR-145 could inhibit HCC cell invasion by regulating the expression of ADAM17.

A recent genome-wide meta-analysis identified six new susceptible genetic variants for nonsyndromic orofacial clefts (NSOC), but it was still unknown whether these newly identified variants were associated with NSOC susceptibility in Chinese populations. In this study, we genotyped these variants in a case-control study of 602 NSOC cases and 605 controls and found that four of these variants (rs7590268, rs7632427, rs12543318, and rs1873147) were associated with susceptibility to NSOC. We further investigated the cumulative effects of these four variants and found a dose-dependent increase in risk with the number of variant alleles. Furthermore, an association was observed between rs7590268 and a family history of NSOC. Our results provide confirmative evidence that these risk loci contribute to NSOC susceptibility in Chinese populations.

Calcium isotopic compositions of sixteen Ca-bearing USGS geological reference materials including igneous and sedimentary rocks are reported. Calcium isotopic compositions were determined in two laboratories (GPMR, State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan; and CIG, Centre for Isotope Geochemistry, University of California, Berkeley) using the 42Ca-48Ca double-spike technique by thermal ionisation mass spectrometry. As opposed to common cation exchange resin, a micro-column filled with Ca-selective resin (DGA resin) was used in order to achieve high recovery (> 96%) and efficient separation of Ca from the sample matrix. The intermediate measurement precision was evaluated at 0.14‰ (2s) for δ44/40CaSRM915a at GPMR, based on replicate measurements of pure Ca reference material NIST SRM 915a, NIST SRM 915b and seawater. Overall, the measurement uncertainties in both laboratories were better than 0.15‰ at the 2s level. Result validation was carried out for all available data sets. The Ca isotopic compositions of USGS reference materials are not only in agreement between GPMR and CIG, but also in agreement with previously published data within quoted uncertainties. The comprehensive data set reported in this study serves as a reference for both quality assurance and interlaboratory comparison of high precision Ca isotopic study.

The diffusible factor synthase XanB2, originally identified in Xanthomonas campestris pv. campestris (Xcc), is highly conserved across a wide range of bacterial species, but its substrate and catalytic mechanism have not yet been investigated. Here, we show that XanB2 is a unique bifunctional chorismatase that hydrolyses chorismate, the end-product of the shikimate pathway, to produce 3-hydroxybenzoic acid (3-HBA) and 4-HBA. 3-HBA and 4-HBA are respectively associated with the yellow pigment xanthomonadin biosynthesis and antioxidant activity in Xcc. We further demonstrate that XanB2 is a structurally novel enzyme with three putative domains. It catalyses 3-HBA and 4-HBA biosynthesis via a unique mechanism with the C-terminal YjgF-like domain conferring activity for 3-HBA biosynthesis and the N-terminal FGFG motif-containing domain responsible for 4-HBA biosynthesis. Furthermore, we show that Xcc produces coenzyme Q8 (CoQ8) via a new biosynthetic pathway independent of the key chorismate-pyruvate lyase UbiC. XanB2 is the alternative source of 4-HBA for CoQ8 biosynthesis. The similar CoQ8 biosynthetic pathway, xanthomonadin biosynthetic gene cluster and XanB2 homologues are well conserved in the bacterial species within Xanthomonas, Xylella, Xylophilus, Pseudoxanthomonas, Rhodanobacter, Frateuria, Herminiimonas and Variovorax, suggesting that XanB2 may be a conserved metabolic link between the shikimate pathway, ubiquinone and xanthomonadin biosynthetic pathways in diverse bacteria.

Tumor-induced osteomalacia (TIO) is an acquired form of hypophosphatemia. Tumor resection leads to cure. We investigated the clinical characteristics of TIO, diagnostic methods, and course after tumor resection in Beijing, China, and compared them with 269 previous published reports of TIO. A total of 94 patients with adult-onset hypophosphatemic osteomalacia were seen over a 6-year period (January, 2004 to May, 2010) in Peking Union Medical College Hospital. After physical examination (PE), all patients underwent technetium-99m octreotide scintigraphy (99Tcm-OCT). Tumors were removed after localization. The results demonstrated that 46 of 94 hypophosphatemic osteomalacia patients had high uptake in 99Tcm-OCT imaging. Forty of them underwent tumor resection with the TIO diagnosis established in 37 patients. In 2 patients, the tumor was discovered on PE but not by 99Tcm-OCT. The gender distribution was equal (M/F = 19/20). Average age was 42 ± 14 years. In 35 patients (90%), the serum phosphorus concentration returned to normal in 5.5 ± 3.0 days after tumor resection. Most of the tumors (85%) were classified as phosphaturic mesenchymal tumor (PMT) or mixed connective tissue variant (PMTMCT). Recurrence of disease was suggested in 3 patients (9%). When combined with the 269 cases reported in the literature, the mean age and sex distribution were similar. The tumors were of bone (40%) and soft tissue (55%) origins, with 42% of the tumors being found in the lower extremities. In summary, TIO is an important cause of adult-onset hypophosphatemia in China. 99Tcm-OCT imaging successfully localized the tumor in the overwhelming majority of patients. Successful removal of tumors leads to cure in most cases, but recurrence should be sought by long-term follow-up. © 2012 American Society for Bone and Mineral Research.

Introduction: The aim of this study was to evaluate over a 180-day period the biocompatibility and retinal support of a foldable capsular vitreous body injected with either saline or silicone oil implanted in rabbit eyes. Methods: A standard three-port pars plana vitrectomy was performed, and foldable capsular vitreous bodies were implanted into the vitreous cavity of rabbit eyes (n = 18). Silicone oil tamponade was used as the control group (n = 5). Of the foldable capsular vitreous body-implanted eyes, either saline (n = 9) or silicone oil (n = 9) was injected into the foldable capsular vitreous body to support the retina. The treated eyes were examined using a slit lamp with a non-contact slit-lamp lens, a tonopen, a non-contact specular microscope and a B-scan ultrasound during the 180-day implantation period. A histological examination was performed at 90 and 180 days. Results: During the 180-day implantation period, no significant corneal keratopathy or intraocular inflammation was noted, and the intraocular pressure (IOP) and corneal endothelial numbers remained steady among the three groups. B-scan ultrasonography showed a smoothly increased echogenicity in front of the retina in group of foldable capsular vitreous bodies injected with saline. Gross examination showed that the foldable capsular vitreous bodies injected with saline or silicone oil smoothly supported the retina. The saline or silicone oil inside the foldable capsular vitreous body was homogeneous, transparent and filled the foldable capsular vitreous body. Histological examination showed no obvious abnormality of the cornea, ciliary body or retina in the foldable capsular vitreous body-implanted eyes. Conclusions: These results suggest that foldable capsular vitreous bodies injected with either saline or silicone oil showed good biocompatibility and retinal support in rabbit eyes over a 180-day implantation time.

MicroRNAs are involved in human carcinogenesis and cancer progression. Our previous study has shown that loss of miR-338-3p expression is associated with clinical aggressiveness of hepatocellular carcinoma (HCC). However, the exact roles and mechanisms of miR-338-3p remain unknown in HCC. To determine whether and how miR-338-3p influences liver cancer cell invasion, we studied miR-338-3p in the liver cancer cell lines, and we found that miR-338-3p is down-regulated in treated cells. Forced expression of miR-338-3p in SK-HEP-1 cells suppressed cell migration and invasion, whereas inhibition of miR-338-3p in SMMC-7721 cells induced cell migration and invasion. Furthermore, smoothened (SMO) was identified as a direct target of miR-338-3p. Forced expression of miR-338-3p down-regulated SMO and matrix metalloproteinase (MMP)-9 expression, but inhibition of miR-338-3p up-regulated SMO and MMP9 expression. However, small interfering RNA targeted SMO reversed the effects induced by blockade of miR-338-3p. SMO and MMP9 were overexpressed and associated with invasion and metastasis in HCC tissues. These data indicate that miR-338-3p suppresses cell invasion by targeting the smoothened gene in liver cancer in vitro and miR-338-3p might be a novel potential strategy for liver cancer treatment.

Dahuang-mudan decoction (DMD) has been widely used for disease treatment in China for 1700 years. The formula consists of Rhubarb, moutan bark, Prunus persica, wax gourd kernel and mirabilite, which have been well studied by multidisciplinary approaches. However, the role of the mineral mirabilite in DMD is unclear. The objective of this study was to investigate the effects of mirabilite on the absorption and pharmacokinetics of the ingredients in DMD. The constituents were identified in DMD extract and the plasma of mirabilite-DMD (MDMD, 50 g kg-1 ) treated rats and nonmirabilite-DMD (NMDMD, 50 g kg-1 ) treated rats. The plasma was also used to investigate the effects of mirabilite on the pharmacokinetics of active ingredients in DMD using a new validated UPLC-MS/MS method. The results showed that 63 compounds were identified in the extract of DMD, 27 and 22 of which were found in the plasmas of MDMD- and NMDMD-treated rats, respectively. Furthermore, the results of a pharmacokinetic study suggested that mirabilite influenced the absorption of the five constituents by decreasing the absorption of emodin and rhein while increasing the absorption of aloe-emodin, paeoniflorin and amygdalin; the pharmacokinetic parameters, including the Tmax , Cmax , AUC0-t , MRT0-t , CLz and t1/2 of five constituents, significantly changed in MDMD-treated rats compared with the NMDMD. The method validation for selectivity, precision, accuracy, matrix effect, recovery and stability met the acceptance criteria. These findings uncover the roles of mirabilite in DMD and demonstrate the application of scientific principles to the study of DMD in human health care.

Aim: Recent studies have underlined causative links between microRNA (miRNA) deregulation and cancer development. However, the relevance of abnormally expressed miRNA to tumor biology has not been well understood in hepatocellular carcinoma (HCC). Methods: A bead-based miRNA expression profiling method was performed on 20 pairs of surgically removed HCC and adjacent non-tumorous tissue (NT). Special miR-338 downregulations and miR-338 associated with clinical characteristics was validated in an extended samples set of 36 paired HCC and adjacent non-tumorous liver tissues by real-time reverse transcription polymerase chain reaction (RT-PCR) analysis. Results: Out of our bead-based microarray data, 12 upregulated and 19 downregulated miRNA were found to be associated with HCC. Further characterization of miRNA-338, in which 20 pairs of the samples were clustered clearly into two groups according to expression of miR-338, revealed that the level of miR-338 expression can be associated with clinical aggressiveness, such as, tumor size, tumor–node–metastasis stage, vascular invasion and intrahepatic metastasis. These results were validated by real-time RT-PCR analysis. Conclusion: Our study suggests that miRNA expression could have relevance to the clinical behavior of HCC and that the bead-based miRNA expression profiling method might be a suitable system to assay miRNA expression in large-scale diagnostic trails.

Our previous study showed that cysteine sulfinate decarboxylase (CSD) is expressed in the testis, epididymis, and ductus deferens. However, the expression of CSD and taurine concentration in the male accessory sex glands remain unknown. Therefore, we conducted immunohistochemical analysis, semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), and western blotting in order to examine CSD expression in the seminal vesicle; bulbourethral gland; and prostate gland, including the dorsolateral prostate, ventral prostate, and anterior prostate. We also analyzed the tissue taurine concentration by using high-performance liquid chromatography (HPLC). Immunohistochemical analysis revealed that CSD is expressed in the tall columnar cells of the seminal vesicle, the glandular epithelium of the bulbourethral gland, and the epithelial cells of the intermediate segments of prostate gland. The taurine concentrations in the dorsolateral prostate, ventral prostate, and anterior prostate; seminal vesicle; and bulbourethral gland in terms of micromoles per gram wet weight were 6.09 ± 0.67, 6.62 ± 0.43, 4.14 ± 0.05, 12.55 ± 1.03, and 7.50 ± 0.64, respectively; these values are similar to the relative expression levels of the CSD protein. These results demonstrate that CSD is expressed in the accessory sex glands of mice, and they confirm our hypothesis that male accessory sex glands are able to synthesize taurine through the CSD pathway.

Xanthomonas campestris pv. campestris (Xcc) is known to regulate virulence through a quorum-sensing mechanism. Detection of the quorum-sensing signal DSF by sensor RpfC leads to activation of the response regulator RpfG, which influences virulence by degrading cyclic-di-GMP and by subsequent increasing expression of the global regulator Clp. In this study, we show that mutation of a response regulator RavR containing the GGDEF-EAL domains decreases Xcc virulence factor production. The functionality of RavR is dependent on its EAL domain-associated cyclic-di-GMP phosphodiesterase activity. Deletion of a multidomain sensor gene ravS, which shares the same operon with ravR, results in similar phenotype changes as the ravR mutant. In addition, the sensor mutant phenotypes can be rescued by in trans expression of the response regulator, supporting the notion that RavS and RavR constitute a two-component regulatory system. Significantly, mutation of either the PAS domain or key residues of RavS implicated in sensing low-oxygen tension abrogates the sensor activity in virulence regulation. Moreover, similar to the DSF signalling system, RavS/RavR regulates virulence gene expression through the global regulator Clp. These results outline a co-regulation mechanism that allows Xcc to integrate population density and environmental cues to modulate virulence factor production and adaptation.

AIM To investigate the status of Phosphatidylinositol 3-kinase (PI3K)/PTEN/AKT/mammalian target of rapamycin (mTOR) pathway and its correlation with clinicopathological features and matrix metalloproteinase-2, -9 (MMP-2, 9) in human hepatocellular carcinoma (HCC). METHODS PTEN, Phosphorylated AKT (p-AKT), Phosphorylated mTOR (p-mTOR), MMP-2, MMP-9 and Ki-67 expression levels were evaluated by immunohistochemistry on tissue microarrays containing 200 HCCs with paired adjacent non-cancerous liver tissues. PTEN, MMP-2 and MMP-9 mRNA levels were determined by real-time RT-PCR in 36 HCCs. The relationships between PI3K/PTEN/AKT/mTOR pathway and clinicopathological factors and MMP-2, 9 were analyzed in HCC. RESULTS In HCC, PTEN loss and overexpression of p-AKT and p-mTOR were associated with tumor grade, intrahepatic metastasis, vascular invasion, TNM stage and high Ki-67 labeling index (P < 0.05). PTEN loss was correlated with p-AKT, p-mTOR and MMP-9 overexpression. Furthermore, PTEN and MMP-2, 9 mRNA levels were down-regulated and up-regulated in HCC compared with paired non-cancerous liver tissues, respectively (P < 0.01). PTEN, MMP-2 and MMP-9 mRNA levels were correlated with tumor stage and metastasis. There was an inverse correlation between PTEN and MMP-9 mRNA expression. However, PI3K/PTEN/AKT/mTOR pathway was not correlated with MMP-2. CONCLUSIONS PI3K/PTEN/AKT/mTOR pathway, which is activated in HCC, is involved in invasion and metastasis through up-regulating MMP-9 in HCC.

Using X-ray diffraction (XRD), scanning electron microscope (SEM), and differential scanning calorimetry (DSC), we have investigated the reaction between MgB4 and Mg in its solid, liquid, and gas physical states. The XRD results indicate that the reaction of MgB4+Mg=2MgB2 always occurs independently of the different states of Mg. DSC measurements show that the solid–solid reaction MgB4(s)+Mg(s)=2MgB2(s), the Mg melting Mg(s)→Mg(l), and the Mg volatilization occur in turn with increasing temperature for mixed (MgB4+Mg) powder with a nominal stoichiometry of MgB2. SEM observations indicate that the resulting synthesized MgB2 samples, obtained from the MgB4+Mg mixtures, have a denser microstructure than those obtained directly from Mg+B mixtures. On the basis of XRD, DSC, and SEM results, a kinetic model for the reaction between MgB4 and Mg is proposed.

A novel prodrug [2,5-bis(4-amidinophenyl)furan-bis-O-methylamidoxime (DB289)] of the promising antimicrobial agent, 2,5-bis(4-amidinophenyl)furan (DB75), has excellent oral activity. It is currently undergoing phase II clinical evaluation as an orally administered drug candidate against African trypanosomiasis and Pneumocystis carinii pneumonia. The sequential product ion (MS(n)) fragmentations of DB289 and selected metabolites were characterized using ion trap mass spectrometry with electrospray ionization. An unusual homolytic bond cleavage, formation of an odd-electron ion from an even-electron ion with the loss of a radical, was commonly seen in the fragmentation patterns of DB289 and its metabolites. Both O-ethyl and N-methyl homologues of DB289 were utilized to confirm this fragmentation pathway. The labile hydrogen atoms in DB289 are readily exchanged with deuterium atoms in the solvent containing deuterium oxide (D2O) instead of water. The mass shift patterns displayed in the product ion spectra of DB289 in D2O proved useful in verifying the fragmentation pathway. Octadeuterated DB289 and DB75 (d-labeling on the diphenyl rings) showed unequivocally that the diphenylfuran moiety is not involved in the fragmentation. The fragmentation pathways uncovered in this work will facilitate structural characterization of all the metabolites produced in the metabolic activation of DB289.