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Cancer stem cells (CSCs) are inherently resistant to chemotherapy, and CSCs in chemotherapy-failed recurrent tumors are enriched; however, the cellular origin of chemotherapy-induced CSC enrichment remains unclear. Communication with stromal fibroblasts may induce cancer cell dedifferentiation into CSCs through secreted factors. We recently demonstrated that fibroblast-derived exosomes promote chemoresistance in colorectal cancer (CRC). Here, we report that fibroblasts confer CRC chemoresistance via exosome-induced reprogramming (dedifferentiation) of bulk CRC cells to phenotypic and functional CSCs. At the molecular level, we provided evidence that the major reprogramming regulators in fibroblast-exosomes are Wnts. Exosomal Wnts were found to increase Wnt activity and drug resistance in differentiated CRC cells, and inhibiting Wnt release diminished this effect in vitro and in vivo. Together, our results indicate that exosomal Wnts derived from fibroblasts could induce the dedifferentiation of cancer cells to promote chemoresistance in CRC, and suggest that interfering with exosomal Wnt signaling may help to improve chemosensitivity and the therapeutic window.

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Multi-environment trials were conducted to investigate the quality potential of synthetic-derived cultivars (SDCs) and non-synthetic-derived cultivars (NSCs) in south-western China. The environmental effect was greater than genotypic for most protein quantity and quality parameters. The genotype effect was greater for falling number and the parameters from the rapid visco analyser (RVA). In terms of group means, grain protein content, wet gluten content, falling number, and RVA parameters were all significantly lower in SDCs than NSCs. No differences in the parameters reflecting dough strength (Zeleny sedimentation volume and farinograph parameters) were found between the two groups. Significant differences existed within each group, and the degree of variation was especially great in SDCs, among which Chuanmai 104 performed well in various quality parameters. Germination index at physiological maturity varied greatly among cultivars, with the lowest being Chuanmai 104, and the SDCs significantly lower than the NSCs. Although delayed harvest resulted in a significant reduction in falling number, partial SDCs such as Chuanmai 104 and Chuanmai 42 expressed relatively small reductions. In summary, SDCs exhibit a higher degree of variation in quality parameters; these findings indicate their large potential for breeding high-quality cultivars in south-western China.

‘DALSA 0605’ (Reg. No. CV‐274, PI 671959) is an embryo rescue‐derived interploid hybrid of St. Augustinegrass [Stenotaphrum secundatum(Walt.) Kuntze] resulting from a cross between TAES 5382 (African triploid PI 291594) and ‘Palmetto’ (diploid). DALSA 0605 was evaluated under the designation TAES 5471‐18 and TXSA 19 and was approved for release as a new cultivar by Texas A&M AgriLife in 2014. DALSA 0605 is a vegetatively propagated, genetically stable, and uniform cultivar. It is distinguished from other cultivars of St. Augustinegrass for traits and characteristics that include (i) tolerance to gray leaf spot disease (caused by Magnaporthe griseaCouch), (ii) significantly reduced levels of fecundity and juvenile development of southern chinch bugs (Blissus insularisBarber) as compared to ‘Raleigh’ and ‘Texas Common’, and (iii) superior drought resistance conferred through a combination of tolerance to drying soil, deep rooting potential, and rapid recovery following drought. In addition, DALSA 0605 exhibited percentage rates of establishment and turfgrass quality ratings (normal and drought‐stress conditions) comparable to commercial checks in multilocation (seven) and multiyear (two) field evaluations. DALSA 0605 is well suited for use on residential and commercial lawns, as well as other recreational sites, throughout the southern and southeastern United States.

Four nanoparticle compositions, Fe–21, 35, 47, and 67 at. % Au, have been prepared to study the phase stability and solid-state transformation in confined Fe–Au nanoalloys. The formation of two phases, predicted from bulk thermodynamics, has been suppressed in all compositions. Instead, a single phase solid solution forms after heat treatment at 600 °C and slow cooling. However, bulk phase relationships, signified by the precipitation of α-Fe upon cooling, was observed in larger particles (>20 nm) with composition Fe–35 at. % Au. The suppression of the phase transformation/precipitation in small particles is explained thermodynamically, as the free energy decrease associated with the phase transformation does not exceed the increase in energy due to the introduction of an interphase interface (grain boundary) within the cluster. A general equation has been derived to predict the critical cluster size below which transformations are inhibited, which agrees well with the observed experimental results.

The maximum biomass yield of switchgrass (Panicum virgatumL.) usually is achieved with one seasonal autumn harvest. However, information is limited on the influences of winter harvesting on annual biomass yield and on quality parameters impacting conversion into bioethanol. Accordingly, the objectives of this study were to assess: (i) yield of standing field cured biomass at monthly intervals through winter, (ii) year‐round elemental composition of biomass, and (iii) associated year‐round soil nutrient status. An unfertilized ‘Kanlow’ switchgrass planting established in 1998 was used for this study conducted from November 2007 to October 2010. The experimental treatment was monthly harvest from November to the following March and year‐round monthly sampling of biomass (except April) and soil for chemical analyses. The 3‐yr mean dry matter yield of winter harvests was 5.94Mg ha−1, ranging from 3.88 Mg ha−1in the winter of 2007–2008 to 7.55 Mg ha−1in 2009–2010. Monthly biomass yield differences were significant in Years 1 and 3 but not in Year 2. Concentrations of biomass elements and soil nutrients changed with various degrees over the 3 yr. Concentrations of ash, cell wall components, and mineral nutrients, except P, K, and S, did not change appreciably across winter months. Early winter harvests resulted in less yield loss compared to late winter harvests. These findings will be valuable in harvest management for switchgrass biomass production.

Bermudagrass, Cynodon dactylon(L.) Pers., is geographically widely distributed and represents the most important taxon in the genus in terms of its extensive uses for turf, forage, soil stabilization, and remediation. This warm‐season, sod‐forming grass is indigenous to China, but limited information is available for adaptive, morphological, and biomass traits in the Chinese germplasm. Accordingly, objectives of this study were to quantify genetic variability for 24 morphological, adaptive, and biomass‐related traits and to characterize relationships among traits of 114 Chinese clonal accessions in a field experiment at Stillwater, OK. ‘Tifsport’, ‘Tifway’, ‘Midland’, and ‘Tifton 44’ bermudagrass cultivars were used as controls in the field experiment. Differences among the accessions were significant (P< 0.01 or P< 0.05) and of large magnitude for all response traits. When grouped by ploidy level, variation among accessions was far greater in tetraploids (104) than in pentaploids (3) and hexaploids (7). Response traits of plant height, leaf blade length and width, and internode length and diameter were significantly and positively correlated with each other to various degrees. Biomass yield was significantly associated with the traits of spring greenup, plant height, winter kill rate, internode, and sod density. Winter kill was positively correlated with weed prolificacy, but negatively with spring greenup. Multiple regression and path coefficient analyses indicated plant height, winter kill, greenup, sod density, and internode size to be predictive of forage yield. The large amount of genetic variability among the Chinese accessions should be a valuable resource for the development of improved turf and forage cultivars.

Moving beds are widely used in many scientific fields due to their advantages, but their operation is affected by the phenomena of cavity and pinning, which should be avoided. In this article, a perforated dividing wall was located in a two‐dimensional rectangular moving bed with gas cross‐flow and the effect of the wall on some properties of the moving bed was investigated. Experimental results show that the location of the perforated dividing wall can improve the upper limit of the gas velocity of the moving bed since it prohibits the existence of a cavity and pinning. The dividing wall separates the apparatus into two channels. A cavity forms in the channel close to the upstream face while pinning occurs in the other channel. In comparison to a moving bed without a dividing wall, the cavity size and pinning width in a moving bed with a dividing wall are smaller at the same gas velocity.

Caragana korshinskiiKom. is a perennial sandy grassland and desert deciduous shrub species, indigenous to and distributed in the northwest of China and Mongolia, and important in vegetation rehabilitation of widely degraded and degrading semiarid and arid regions because of its high ecological and economic values. To assess the genetic diversity and population structure of C. korshinskii, 10 natural populations from the Loess plateau and Inner Mongolia plateau in China were analyzed for amplified fragment length polymorphisms. Four primer combinations produced 358 bands across a total of 98 individuals. A high percentage of polymorphic loci was observed at species level (p= 93.9%). Multivariate analyses separated accessions into two regional groups corresponding to the Loess and Inner Mongolia plateaus. Based on analysis of molecular variance, 77.8% of the genetic variation of C. korshinskiiwas within population, 7% difference between regions, and 15.2% among collection sites within regions. An indirect estimate of the number of migrants per generation (Nm= 1.7) indicated that gene flow was high among populations of the species. A significant correlation (r= 0.58) between genetic and geographic distance was detected. Results of this study suggested that C. korshinskiihas a high genetic variability and potential as a source of variation for breeding programs.

Electrochemical properties of eight methanofullerene films, prepared on electrodes by casting, were examined by means of cyclic voltammetry and electrochemical quartz crystal microbalance (EQCM) technique in acetonitrile solution. Compared with C60 film, the film stability with respect to dissolution is associated with the length of the alkyl chains introduced into C60 cage and is strongly dependent on the nature of the cation of the supporting electrolyte. TBA+, Li+, K+, and Na+ were selected to observe the effect of countercations on the electrochemical behavior of methanofullerene films. In TBAPF6 solution, when short chains, such as formic ether or butyl butyrate groups, were introduced into C60 cage, the film stability was less than that of C60. When the length of the alkyl chain was extended to butyl 12 alkanoate group, the film would not dissolve until the third reduction process because the long alkyl chain could inflect and encase the cations into the film. In KPF6 or NaClO4 solution, however, the solubility of the salt formed by K+ or Na+ with methanofullerene anion was higher than that formed by TBA+ with methanofullerene anion. Li+ (alkali metal) affected the behavior of the films in different ways. The possible electron‐transfer mechanisms of methanofullerene films in various supporting electrolyte solutions were presented. Furthermore, the film images observed by atomic force microscopy indicated that TBA+ and Li+ affected the behavior of the methanofullerene films in different ways. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3634–3640, 2006

Bermudagrass [Cynodon dactylon(L.) Pers.] is widely distributed in China, but little information exists on genetic diversity within the germplasm pool. This study was conducted to assess variations in ploidy and amplified fragment length polymorphisms (AFLPs) among Cynodonaccessions collected from 11 Chinese provinces. Flow cytometry and AFLP analyses were performed on 132 and 119 Chinese accessions, respectively. Four ploidy cytotypes were found among the Chinese accessions. Tetraploid (2n= 4x= 36) accessions were most prevalent (88%), with nuclear genome sizes ranging from 1.96 to 2.30 pg/2C nucleus−1Seven hexaploid (2n= 6x= 54), three pentaploid (2n= 5x =45), and six triploid (2n= 3x= 27) accessions had respective nuclear genome size of 2.90 to 3.13, 2.37 to 2.49, and 1.55 to 1.65 pg/2C nucleus−1The accessions were grouped into five clusters based on 466 polymorphic AFLP bands. Genetic similarity coefficients (GSCs) of two clusters containing ‘Tifway’ and ‘Tifgreen’ ranged from 0.97 to 0.99, suggesting the triploid plants most probably were introduced cultivars from the USA. Within the Chinese indigenous accessions, GSC ranged from 0.65 to 0.99. Tetraploid genotypes had the greatest genetic variation with GSC ranging from 0.69 to 0.99, while pentaploids had the least with GSC ranging from 0.95 to 0.98. Genetic differentiation among the later three ploidy levels is evident. Fully sampling the genetic diversity of Cynodonin China will require more comprehensive collection throughout its distribution.

Cynodon transvaalensisBurtt‐Davy (African bermudagrass) is valued as turf and for use in interspecific hybridization with C. dactylon(L.) Pers. var. dactylonto produce turf cultivars. Little information is available regarding the magnitude of genetic variation within the taxon. Accordingly, this study was undertaken to evaluate the genetic diversity among 14 C. transvaalensisaccessions and to examine the phylogenetic relatedness of C. transvaalensis, two hexaploid (2n= 6x= 54) C. dactylonvar. dactylonaccessions, two C. transvaalensisby hexaploid C. dactylonvar. dactyloninterspecific tetraploid (2n= 4x= 36) F1hybrids, and one putative tetraploid C. dactylonvar. dactylonby C. transvaalensistriploid (2n= 3x= 27) F1hybrid. Fluorescence‐labeled amplified fragment length polymorphism (AFLP) DNA profiling was used to study the genetic relationships among these accessions. A total of 381 polymorphic AFLP markers were amplified from 13 primer combinations. The 14 C. transvaalensisaccessions and the putative triploid F1hybrid clustered into one group and had genetic dissimilarity coefficients ranging from 0.01 to 0.51. The 14 C. transvaalensisaccessions had genetic dissimilarity coefficients ranging from 0.01 to 0.34. The C. dactylonvar. dactylonaccessions and the two tetraploid F1hybrids clustered in the second group, with genetic dissimilarity coefficients ranging from 0.17 to 0.33. The tetraploid F1hybrids were more closely related to C. dactylonvar. dactylonthan to C. transvaalensis, while the opposite was true for the putative triploid F1hybrid. The results indicate the presence of genetic diversity in C. transvaalensisthat could be exploited in intra‐ and interspecific breeding improvement.

Peptidylprolyl isomerase cyclophilins play critical roles in a variety of biological processes. Recent findings that cyclophilins are present at high levels in the CNS and that cyclosporin A may possess neuroprotective/neurotrophic effects have prompted us to search for nonimmunosuppressant small molecule cyclophilin ligands. To this end, we report the lead identification through “virtual screening” and the synthesis of our first series of non-peptidic cyclophilin ligands, along with the preliminary biological results.

The recently discovered small-molecule ligands for the peptidyl and prolyl isomerases (PPIase) of FKBP12 have been shown to possess powerful neuroprotective and neuroregenerative effects. Ketone analogues of the prolyl and pipecolyl esters, which mimic only the FKBP binding domain portion of FK506, are proposed and an efficient synthetic strategy is presented in this report, along with the preliminary results of in vitro and in vivo biological studies.

The recent discovery that small molecule ligands for the peptidyl−prolyl isomerase (PPIase) FKBP12 possess powerful neuroprotective and neuroregenerative properties in vitro and in vivo suggests therapeutic utility for such compounds in neurodegenerative disease. The neurotrophic effects of these compounds are independent of the immunosuppressive pathways by which drugs such as FK506 and rapamycin operate. Previous work by ourselves and other groups exploring the structure−activity relationships (SAR) of small molecules that mimic only the FKBP binding domain portion of FK506 has focused on esters of proline and pipecolic acid. We have explored amide and thioester analogues of these earlier structures and found that they too are extremely potent in promoting recovery of lesioned dopaminergic pathways in a mouse model of Parkinson's disease. Several compounds were shown to be highly effective upon oral administration after lesioning of the dopaminergic pathway, providing further evidence of the potential clinical utility of a variety of structural classes of FKBP12 ligands.

An experimental apparatus that mimicked CO2 removal was established to evaluate a suitable solvent for CO2 removal under conditions approaching those of commercial reality. By this apparatus, various concentrations of methyldiethanolamine (MDEA) aqueous solutions and various ratios of methyldiethanolamine to piperazine (PZ) in activated MDEA solution were studied, and the results indicated that the optimum concentration of MDEA aqueous solution is 3.0 M and the optimum weight ratio of MDEA to PZ is 50/5.

Abstract.: We show that if a simple 3-manifold M has two Dehn fillings at distance , each of which contains an essential annulus, then M is one of three specific 2-component link exteriors in S 3 . One of these has such a pair of annular fillings with , and the other two have pairs with .

Summary Based on the statistical data of the nationwide occupational diseases reporting in 1986–1988, lead poisoning stood the first place of chronic occupational poisonings in China. Biological monitoring of lead exposure is of paramount importance in both occupational and environmental health. In order to ensure lead testing data valid enough for taking actions of prevention and control, a quality assurance scheme including selection of reliable analytical techniques, establishing reference laboratory, application of standard reference materials, and conducting internal and external quality control program was implemented in China. Since the rigid assurance procedure was conducted during studies on “background levels of lead in non-exposure population” and “revision of the diagnostic criteria for lead”, compatible and reliable results were obtained.

Three independent point mutations within residues 97 to 103 of the simian virus 40-small-t antigen (small-t) greatly reduced the ability of purified small-t to inhibit protein phosphatase 2A in vitro. These mutations affected the interaction of small-t antigen with the protein phosphatase 2A A subunit translated in vitro, and a peptide from the region identified by these mutations released the A subunit from immune complexes. When introduced into virus, the mutations eliminated the ability of small-t to enhance viral transformation of growth-arrested rat F111 cells. In contrast, the mutant small-t antigens were unimpaired in the transactivation of the adenovirus E2 promoter, an activity which was reduced by a double mutation in small-t residues 43 and 45.

Abstract: Objectives: To assess and compare the background exposure of the general population to lead (Pb) and cadmium (Cd) in China and in Japan. Methods: Food duplicates and peripheral blood samples were collected from nonoccupationally exposed subjects, viz 202 Chinese women in four Chinese cities (Beijing, Shanghai, Nanning, and Tainan) and 72 Japanese women in three Japanese cities (Tokyo, Kyoto, and Sendai) in the years 1993–1995. Wet-ashing and graphite furnace atomic absorption spectrometric methods were used for the determination of Pb and Cd levels in food and blood samples. Results: Geometric mean (GM) dietary Pb intake (25.8 μg/day) and the GM Pb concentration in blood (56.7 μg/l) in Chinese were significantly higher than in Japanese women (11.6 μg/day in food and 32.1 μg/l in blood), whereas Cd in food (32.1 μg/day) and Cd in blood (1.92 μg/l) in Japanese were significantly higher than in Chinese women (9.9 μg/day in food and 1.07 μg/l in blood). The intake of Pb and Cd via boiled rice accounted for 3.6% and 31.1% of the total dietary burden in Chinese, and 12.1% and 32.7% in Japanese, respectively. The Cd burden was acquired almost exclusively through the dietary route, whereas the Pb burden came from both air and food, especially in the case of the Chinese population. Conclusions:  The background Pb exposure in the Chinese population was higher than that in the Japanese population, whereas Cd exposure was lower in Chinese women than in their Japanese counterparts.

A mild, efficient, and high-yielding method for the synthesis of N,N‘-diaryl cyanoguanidines from their corresponding thioureas under microwave-assisted conditions is described. A series of cyanoguanidines were synthesized containing both electron-donating and electron-withdrawing substituents. The reactions were facilitated by the use of polar solvents along with moderate temperatures.

A mild and high-yielding cyanating reaction of amine, sulfur, and carbanion nucleophiles is reported here using 1-cyanoimidazole as an electrophilic cyanating agent.

The nonlinear third-order optical susceptibility of C70 in a toluene solution is measured for the first time by the method of degenerate four-wave mixing using 10 ns laser pulses at 1.06 µm. The third-order susceptibility Xin(3)is 5.6×10-12 esu for a C70 toluene solution at a concentration of 0.476 g/l. The correspondent magnitude of the hyperpolarizability ?1111 of the C70 molecule is 1.2×10-30 esu which is in a good agreement with the prediction given by the model of a free electron in a spherical box.

The effect of different fibers on mechanical properties and ductility of alkali-activated slag cementitious material (AASCM) is studied. The research contents include: fiber type (plant fiber, polypropylene fiber), fiber content, mechanical property index, tensile stress-strain relationship curve, treating time. The test results showed that the compressive strength of two fibers reinforced AASCM was about 90 ~ 110MPa, and the tensile strength was about 3 ~ 5MPa. The reinforcement effect of polypropylene fiber is superior to that of plant fiber, and the mechanical properties of polypropylene fiber reinforced AASCM are superior to those of plant fiber, According to the comparison of SEM pictures, the plant fiber and polypropylene fiber are both closely bound with the matrix, and the transition zones are complete and close. Thus, it is proved that plant fiber and polypropylene fiber delay the crack extension and enhance the ductility of AASCM.

Aphids are a group of insects frequently associated with bacterial symbionts. Although Chinese aphids harbor a high level of species diversity, the associations between Chinese aphids and bacterial symbionts are less known. In this study, we uncovered the diversity of bacterial symbionts in a Chinese widespread aphid, Sitobion miscanthi (Takahashi). In this study, we detected the aphid obligate symbiont Buchnera aphidicola, and two secondary symbionts, Hamiltonella defensa and Regiella insecticola, with the diagnostic polymerase chain reaction method in S. miscanthi samples. In addition, symbiotic species of Acinetobacter, Aeromonas, Enterobacter, Pantoea, and Pseudomonas, and the family Enterobacteriaceae were also found. Geographically, sporadic occurrences were detected for H. defensa and R. insecticola. Moreover, the infection rates of them vary widely among the infected populations: H. defensa (5.26-95.2%) and R. insecticola (5.26-46.7%). Phylogenetic analyses indicated that the strain of B. aphidicola mirrored the history and divergence of S. miscanthi; however, the H. defensa and R. insecticola strains were probably experienced horizontal transmission among S. miscanthi and its distantly related species.

Greenbug, Schizaphis graminum (Rondani), represents the most important pest insect of sorghum, Sorghum bicolor (L.) Moench, in the Great Plains of the United States. Biotype E is the most widespread and dominant type not only in sorghum and wheat, Triticum aestivum L., fields, but also on many noncultivated grass species. This study was designed to determine sorghum accession PI 550610 resistance to greenbug biotype E, to map the resistance quantitative trait loci (QTLs) by using an established simple sequence repeat (SSR) linkage map and to identify SSR markers closely linked to the major resistance QTLs. In greenhouse screening tests, seedlings of PI 550610 showed strong resistance to the greenbug at a level similar to resistant accession PI 550607. For QTL mapping, one F2 population containing 277 progeny and one population containing 233 F2:3 families derived from Westland A line × PI 550610 were used to genotype 132 polymorphic SSR markers and to phenotype seedling resistance to greenbug feeding. Phenotypic evaluation of sorghum seedling damage at 7, 12, 17, and 21 d postinfestation in the F2:3 families revealed that resistance variation was normally distributed. Single marker analysis indicated 16 SSRs spread over five chromosomes were significant for greenbug resistance. Composite interval and multiple interval mapping procedures indicated that a major QTL resided in the interval of 6.8 cM between SSR markers Xtxp358 and Xtxp289 on SBI-09. The results will be valuable in the development of new greenbug biotype E resistant sorghum cultivars and for the further characterization of major genes by map-based cloning.

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