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Many cities are located in the downstream areas of rivers. Rapid urbanization may result in drastic changes in the urban river ecosystem. Antibiotic resistant genes (ARGs) are considered to be emerging environmental pollutants, which may do harm to the health of humans and may pose a potential risk for urban ecological safety by the dissemination and enrichment of ARGs in urban rivers. In this study, a high-throughput quantitative PCR technique was used to investigate the diversity and abundance of ARGs at three sites in Lianjiang County and the estuary of the Aojiang River, Fujian Province. The results show the abundance of ARGs in the downstream urban area of Lianjiang County (3.9×10 10 copies·L -1 ) is significantly higher than upstream of the urban area and the estuary of the Aojiang River. A total of 129 ARGs are detected in the downstream urban area, which is higher than in the upstream and the estuary. The results also suggest that ARGs are persistent and not easy to reduce in the natural river following the occurrence of ARGs and indicated that the urban river is an important reservoir of ARGs.

Three new sesquiterpenes of canusesnol K (1), canusesnol L (2) and 12, 15-dihydroxycurcumene (3), along with five known ones (4-8), were isolated from the heartwood extract of Pterocarpus santalinus. Their structures were established by extensive analyses of 1D and 2D NMR spectroscopy, including 1 H NMR, 13 C NMR, HSQC, HMBC and NOESY, and HRESI-MS. The absolute configurations of the new compounds were established with Modified Mosher's method. The cytotoxic activities of all these compounds against HepG2 (human liver cancer), MCF-7 (human breast cancer), MDA-MB-231 (human breast cancer), and Hela (human cervical carcinoma) cancer cell lines were evaluated. Compound 1 exhibited moderate cytotoxic activity toward MDA-MB-231 cell lines.

The low quantum efficiency and limited adsorption efficiency of TiO 2 makes it only fit for the removal of VOCs with low concentrations. Herein, we for the first time fabricated nanostructured TiO 2 /activated carbon fiber felt (TiO 2 /ACFF) porous composites by the in situ deposition of TiO 2 microspheres on the carbon fibers in ACFF. Interestingly, the TiO 2 microspheres exhibit hierarchical nanostructures constructed by nanocrystals as building blocks. The TiO 2 /ACFF porous composites possess excellent adsorption and photodegradation properties for toluene because of the synergetic effects between the nanostructured TiO 2 and ACFF. The adsorption efficiencies of the TiO 2 /ACFF porous composites reach approximately 98% at the toluene concentration (<1150ppm) and approximately 77% even at the high concentration of 6900ppm. Moreover, the ACFF in the TiO 2 /ACFF porous composites significantly enhances photocatalytic property for toluene by hindering the recombination of electron-hole pairs, reducing the TiO 2 band gap energy (E g ) to 2.95eV and accelerating toluene adsorption. At the toluene concentrations of 230ppm and 460ppm, the photocatalytic oxidation efficiency of toluene into CO 2 arrives at 100% and 81.5%, respectively. Therefore, the TiO 2 /ACFF porous composites with synergetic adsorption and photocatalytic activities have great potentials for toluene removal., (Copyright © 2017 Elsevier B.V. All rights reserved.)

There is a need to find better strategies to promote wound healing, especially of chronic wounds, which remain a challenge. We found that synovium mesenchymal stem cells (SMSCs) have the ability to strongly promote cell proliferation of fibroblasts; however, they are ineffective at promoting angiogenesis. Using gene overexpression technology, we overexpressed microRNA-126-3p (miR-126-3p) and transferred the angiogenic ability of endothelial progenitor cells to SMSCs, promoting angiogenesis. We tested a therapeutic strategy involving controlled-release exosomes derived from miR-126-3p-overexpressing SMSCs combined with chitosan. Our in vitro results showed that exosomes derived from miR-126-3p-overexpressing SMSCs (SMSC-126-Exos) stimulated the proliferation of human dermal fibroblasts and human dermal microvascular endothelial cells (HMEC-1) in a dose-dependent manner. Furthermore, SMSC-126-Exos also promoted migration and tube formation of HMEC-1. Testing this system in a diabetic rat model, we found that this approach resulted in accelerated re-epithelialization, activated angiogenesis, and promotion of collagen maturity in vivo. These data provide the first evidence of the potential of SMSC-126-Exos in treating cutaneous wounds and indicate that modifying the cells-for example, by gene overexpression-and using the exosomes derived from these modified cells provides a potential drug delivery system and could have infinite possibilities for future therapy. Stem Cells Translational Medicine 2017;6:736-747., (© 2016 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.)

Postoperative implant-associated infection remains a serious complication in total joint arthroplasty (TJA) surgery. The addition of antibiotics to bone cement is used as an antimicrobial prophylaxis in cemented joint arthroplasty; however, in cementless arthroplasty, there are no comparable measures for the local delivery of antibiotics. In this study, a gentamicin-loaded Fe3O4/carbonated hydroxyapatite coating (Gent-MCHC) was fabricated according to the following steps: (i) deposition of Fe3O4/CaCO3 particles on Ti6Al4V substrates by electrophoretic deposition; (ii) conversions of MCHC from Fe3O4/CaCO3 coatings by chemical treatment; and (iii) formation of Gent-MCHC by loading gentamicin into MCHC. MCHC possessed mesoporous structure with a pore size of about 3.8 nm and magnetic property with the saturation magnetization strength of about 4.03 emu/g. Gent-MCHC had higher drug loading efficiency and drug release capacity, and superior biocompatibility and mitogenic activity than Ti6Al4V. Moreover, Gent-MCHC deterred bacterial adhesion and prevented biofilm formation. These results demonstrate that Gent-MCHC can be used as a local drug delivery system to prevent implant-associated infection in TJA surgery., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In order to improve the biocompatibility of metallic implants, bioactive components are often used as coatings so that a real bond with the surrounding bone tissue can be formed. We prepared ethyl cellulose/carbonated hydroxyapatite composite coatings (ECHCs) on Ti6Al4V substrates with carbonated hydroxyapatite coatings (CHACs) without ethyl cellulose as controls. The inorganic constituent on the CHACs and ECHCs is calcium-deficient carbonated hydroxyapatite with a flaky texture and a low degree of crystallinity. The flaky carbonated hydroxyapatite plates aggregate to form macropores with an aperture size of around 0.5-2.0 μm. The presence of ethyl cellulose provides superior morphology, contact angle, and biocompatibility characteristics. In comparison to CHACs, ECHCs exhibit a smoother, crack-free surface because the cracks are filled by ethyl cellulose. Moreover, the contact angle of ECHCs is 37.3°, greater than that of CHACs (13.0°). Surface biocompatibility was investigated by using human bone mesenchymal stem cells (hBMSCs). The attachment, spreadability, viability and proliferation of hBMSCs on ECHCs are superior to those on CHACs. Thus, the crack-free ECHCs have excellent biocompatibility and are appropriate for use as biological implants.

Implant-associated infection remains a difficult medical problem in orthopaedic surgery. Here, we report on the fabrication of gentamicin-loaded mesoporous bioactive glass (Gent-MBG) for use as a controlled antibiotic delivery system to achieve the sustained release of antibiotics in the local sites of bone defects. The high surface area and mesoporous structure of MBG enable higher drug loading efficiency (79-83 %) than non-mesoporous biological glass (NBG) (18-19 %). Gent-MBG exhibits sustained drug release for more than 6 days, and this controlled release of gentamicin significantly inhibits bacterial adhesion and prevents biofilm formation by S. aureus (ATCC25923) and S. epidermidis (ATCC35984). Biocompatibility tests with human bone marrow stromal cells (hBMSCs) indicate that MBG has better biocompatibility than NBG. Therefore, Gent-MBG can be used as a controlled drug delivery system to prevent and/or treat orthopedic peri-implant infections.

One strain, identified as Streptomyces sp. FX645 which was isolated from the sludge collected in a printing and dyeing mill, had high potency of degradation and decolourisation of azo dye Red 30 (AR30). The microbial degradation mechanism on AR30 by strain FX645 was proposed through analyzing the UV-vis spectra and LC-MS spectra of the degradation products and investigating the variations in the concentrations of the degradation products in the culture. It is suggested that the azo bond of AR30 was iniially cracked by azo reductase to produce 2,6-dichloro- 4-nitrobenzenamine and 2-[(4-aminophenyl)-(2-cyanoethyl) amino] ethylacetate, which then generated several aromatic amine compounds under the actions of nitror4duction, aminoacylation and cyano hydrolysis, respectively.

In order to study the genetic diversity and genetic structure of populations, 7 populations of Oxya chinensis from 7 provinces (or cities) of China were analyzed using AFLP technique. A total of 336 reproducible bands were amplified with 7 primer combinations from 128 individuals. Two hundred and ninety-two bands (86.90%) were polymorphic. High genetic diversity was found among O. chinensis populations and Wanning population had higher genetic diversity than other populations. Mantel test (r=0.27, P=0.89) suggested that there was no significant association between genetic distance and geographic distance. Remarkable genetic differentiation was found among populations. Unweighted pair group method average (UPGMA) tree showed that the 7 O. chinensis populations were divided into 3 groups: Changping of Beijing, Tai-yuan of Shanxi and Jining of Shandong populations in the north; Hanzhong of Shaanxi, Changsha of Hunan and Laibin of Guangxi populations in the south; and Wanning of Hainan population. Principal component analysis indicated significant genetic differentiation of the north and the south populations and island and continent populations existed in the 7 O. chinensis populations because of geographic isolation.

The toxic effects of Cr(VI) on antioxidant enzymes of Oxya chinensis (Orthoptera: Acridoidae) were determined. Changes in the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and guaiacol peroxidase (GPx) were measured in O. chinensis insects injected with Cr(VI). Fifth-nymphs of O. chinensis insects were injected with Cr(VI) with different concentrations (0, 75, 150, 225, 300, 375, 450 mg/kg of body weight). The results showed that Cr(VI) led to the change of SOD, CAT, and GPx activities at different concentrations, which revealed that: (1) The oxidative stress of SOD increased with the increase of Cr(VI) concentration. (2) With the increase of Cr(VI) concentrations, CAT activities for females increased at lower concentrations, but decreased at higher concentration range, which indicated that antioxidant system of O. chinensis was not influenced by the presence of Cr(VI). A very similar response to Cr(VI) effect for males indicated that Cr(VI) concentrations were not high enough to damage O. chinensis in terms of CAT. (3) The GPx activity for females increased in all treatments, which revealed that the damage power of Cr(VI) was increased with the increase of Cr(VI) concentrations in terms of GPx, but the effect was not so remarkable. There was not a consistent trend of GPx activities for males in all treatments of Cr(VI). Cr (VI)-induced changes in antioxidant enzymes were different for SOD, CAT and GPx, of which the tendency was that activities generally changed with increase of concentrations of Cr(VI) suggesting SOD, CAT, and GPx could serve as indices of oxidative stress to some extent.

The rice grasshopper Oxya chinensis exhibits polymorphic loci at Ldh, Gpi, Pgm and Me. The data of the mean number of alleles per locus (A = 2.8), percentage of polymorphic loci (P = 80.0%), the observed mean heterozygosities (Ho = 0.271 approximately 0.279) and the expected mean heterozygosities (He = 0.305 approximately 0.316) of the species suggest that O. chinensis possesses sufficient genetic diversity. It was hypothesized that the high polymorphisms at Ldh, Gpi, Pgm and Me might make it possible for pesticide avermectin to act as a selective agent through differential lethality among the insect individuals with different genotypes. In this study a total of 855 grasshoppers were injected with avermectin (1.3 x 10(-2) g/g) to obtain a mortality of 54% after 24 hours. The allozyme analysis was then employed to determine the genotypes of Ldh, Gpi, Pgm and Me for both dead and surviving individuals. Contingency table chi2 tests showed that avermectin displayed random lethal effects on the genotypes at the loci of Ldh, Pgm and Me, without correlation between the genotype and mortality. In contrast, at Gpi locus, the grasshopper demonstrated a mortality cline of Gpi-AA (38%), Gpi-AB (51%), Gpi-BB (58%) and Gpi-BC (74%). The significant mortality differences were found among the following genotype pairs: Gpi-AA vs. Gpi-BB, Gpi-AA vs. Gpi-BC and Gpi-AB vs. Gpi-BC. These data implied the Gpi-AA genotype was likely related to the specie's resistance to the pesticide avermectin. It was also noted that the Gpi-A allele was present in the genotypes with low morality,while Gpi-B was present in the genotypes with moderate mortality, and the individuals with Gpi-C allele exhibited the highest mortality. The data obtained in this study suggested that the increasing proportion of Gpi-AA genotype and perhaps Gpi-A allele in a population may be useful as a potential resistant biomarker of O. chinensis to pesticide avermectin.

Allozyme electrophoresis was employed to compare the difference in mortality among the genotypes at two polymorphic loci of Pgm and Me of grasshopper Oxya chinensis individuals acutely exposed to 1.5g/L malathion which resulted in 56% mortality in 24 hours. The selective lethal effects were observed among the genotypes at Pgm locus but not at Me locus. It is noted that the genotype Pgm-ab experienced the highest mortality (80%), whereas Pgm-bb and Pgm-bc were 49%, lower than the average. The chi(2) tests showed significant difference in morality between Pgm-bb and Pgm-cc. After exposure the allele frequency of Pgm-b showed a notable increase among surviving individuals. The cluster analysis based on Roger's genetic distance indicated that the acute exposure to malathion can cause differentiation in genetic composition at population level in Oxya chinensis. Because malathion is commonly used as the insecticide for grasshopper control, the data obtained in this study suggest that the similar genotype-mortality effects may occur in crop fields.

Random Amplified Polymorphic DNA (RAPD) markers were applied to analyze genetic relationships of five populations of Oxya chinensis collected from Shanxi Province and laner Mongolia, Oxya japonica from Guangxi was used as an outgroup. Genomic DNA of sixty-four individuals was extracted from dissected leg muscle using phenol-chloroform procedure, and then amplified by 10 random primers (10 bp), the amplified products were separated by agarose gel electrophoresis. The results were as follows: (1) a total of 115 clear and reproducible bands were generated, molecular size was 200 - 2500 bp. The obtaining segments of individual primer were among 5 - 15, on average, about 12 bands per primer. (2) The dendrogram based on 115 RAPD markers was constructed and clustered using between-groups linkage method. The cluster analysis indicated strong similarities within populations, firstly, the individuals in each population closely clustered together;and then five populations of Oxya chinensis could be distinguished with RAPD markers and were grouped into two distinct clusters. The dendrogram showed that Shanxi Linyi population and Tunliu population were the most similar,which were clustered with Taiyuan population Shanxi into one cluster, while, Daixian population in Shanxi was closely related to laner Mongolia population, both of which belonged to the other cluster. Nevertheless, All the five populations of Oxya chinensis had far genetic distance with Oxya japonica. In the dendrogram, a tendency of clustering following a North-South gradient could be observed, the results implied that genetic distance of five populations of Oxya chinensis correlated with geographical distance to some degree.

The genetic structure of the two populations of Pararcyptera microptera meridionalis (Ikonn.) from Hebei and Liaoning in China was analyzed with horizontal starch gel electrophoresis. Among 15 loci of 11 enzymes identified in zymograms, Adk-1, Fbp-1, Mdh-2 and G3pd-1 showed low variability with few alleles. Higher allelic polymorphisms were observed at Fbp-2, Mdh-1 and Me-1. The two populations demonstrated high percentage of polymorphic loci (93.3% and 100.0%) but low observable overall heterozygosity (0.061 and 0.086), that could be attributed to heterozygote deficiencies, which led to the genotype frequency deviating from Hardy-Weinberg expectations. It is reasoned that the strong movement capability of the insect makes the individuals likely to be exposed to drastically varied environments, which tends to maintain dynamic equilibrium of genetic polymorphisms. The F-statistics between the two populations was comparatively smaller ( F(st) = 0.084), but larger when compared with those in migratory locusts like Locusta migratoria manilensis. Nei's genetic identity (I) and Roger's genetic distance (D) also showed close genetic relationship of the two populations by their high genetic identity (I = 0.904) and small genetic distance (D = 0.256). However,considerably qualitative and quantitative differences were noted at loci Acp-1 (F(st) = 0.462) and Pgi-1 (F(st) = 0.182).

The molecular phylogenetic relationships of five species of Oxya Audient-serville including O. chinensis, O. brachyptera, O. agavisa, O. japonica and O. intricata were studied with RAPD. Genomic DNA of forty-one individuals were amplified with eight oligonucleotide (10 mer) primers which were previously selected, the specifical bands occured in all them, a total of 96 clear and reproducible bands (rang from 200-2500 bp) were generated, 95 of which were polymorphic band, the only one band (850 bp) which was amplified with S362 was common to five species of Oxya. The obtaining segments of individual primer were between 8-16, the average was 12. A molecular phylogenetic tree based on was constructed Euclidean distance among five species of rice grasshopper by between-groups linkage method, the result indicated O. chinensis was closely related to O. brachyptera, the genetic relationship of O. japonica and O. agavisa was also close, whereas O. intricata had far phylogenetic relationship with them. The results of dendrogram were consistent with the previous conclusion of morphologic classification and cytotaxonomy, and suggested RAPD was suitable for analysis of phylogenetic relationships among species of Oxya.

The mtDNA Cyt b genes (432 bp) were sequenced for 16 individuals of Oxya agavisa from 7 Chinese region, 3 other relative species (O. japonica, O. chinensis and O. intricata), and two outgroup species (Pseudomorphacris hollisi and Tetrix japonica). In the obtained sequences of O. agavisa, A% + T% was about 71.0% and 9 polymorphic nucleotide sites were observed (about 2.08%), among which no transversions were observed and only one substitution resulted in the variation of amino acid. In the case of 3 other species of Oxya, A% + T% was about 72.5% (O. chinensis) and 70% (O. japonica and O. intricata), respectively. A% + T% in the third site was much higher than the other two sites in all the analyzed Oxya species (O. agavisa, 88.3%; O. chinensis, 92.4%; O. japonica, 86.8%; O. intricata, 89.5%). Six haplotypes of O. agavisa were compared with the 3 other Oxya species and 73 polymorphic nucleotide sites were examined (about 16.9%) in all. Phylogenetic tree was constructed with the Neighbor-Joining methods using P. hollisi and T. japonica as outgroups and the confidence of nodes in the tree was evaluated by Bootstrap(1000 replicates). The NJ tree showed that different haplotypes of O. agavisa clustered together, but no clear relationships between haplotypes and the geographic regions would be inferred. The population from Mount Wuyi belongs to the peculiar group and is relatively distant to other populations. In addition, the NJ tree showed that O. agavisa was closer to O. japonica and O. chinensis closer to O. intricata, which was different from the previous results of morphologic, chromosome karyotype and bands. The relationships among different species of Oxya still need to be further clarified.

The mtDNA Cyt b sequences (432 bp) were analyzed in 10 individuals from 8 different families of Acridoidea in China. The homologous sequences were compared, the used frequency of nucleotide was calculated and the molecular phylogenetic tree constructed by Neighbor-Joining method using T. japonica as outgroup. The confidence of nodes in the trees was evaluated by bootstrap (1000 replicates). These sequences were the middle part of Cyt b gene, and in the obtained sequences, A% + T% was about 70.4% and G% + C% only 29.6%. The sequence data revealed considerable variation in 177 nucleotide sites (about 41.0%) among the analyzed individuals from 8 different families. From every amino acid codon, A% + T% in the third site was higher (86.6%) than the other two sites and lower than other insects in the corresponding region. The NJ tree suggested that 11 individuals from the 8 families clustered in 4 groups, among which Gomphoceridae and Pamphagidae firstly clustered and then together with Arcypteridae and Acrididae to form group I; Cluster II was made of three species from Catantopidae, O. japonica, O. chinensis and O. intricata; Pyrgmorphidae and Oedipodidae formed group III and Chrotogonidae single as cluster IV, respectively. The phylogenetic relationships of the 8 families was: Chrotogonidae-->Pyrgomorphidae and Oedipodidae-->Catantopidae-->Acrididae-->Arcypteridae-->Gomphoceridae and Pamphagidae, which is little different from the morphological results.