Search

Background: Pretreatment of biomass to maximize the recovery of fermentable sugars as well as to minimize the amount of enzyme inhibitors formed during the pretreatment is a challenge in biofuel process. We develop a modified Fenton pretreatment in a mixed solvent (water/DMSO) to combine the advantages of organosolv and Fenton pretreatments. The hemicellulose and cellulose in corncob were effectively degraded into xylose, glucose, and soluble glucose oligomers in a few hours. This saccharide solution, separated from the solid lignin simply by filtration, can be directly applied to the subsequent enzymatic hydrolysis and ethanol fermentation., Results: After the pretreatment, 94% carbohydrates were recovered as soluble monosaccharide (xylose and glucose) and glucose oligomers in the filtrates, and 87% of solid lignin was recovered as the filter residue. The filtrates were directly applied to enzymatic hydrolysis, and 92% of raw corncob glucose was recovered. The hydrolysates containing the glucose and xylose from the enzymatic hydrolysis were directly applied to ethanol fermentation with ethanol yield equals 79% of theoretical yield. The pretreatment conditions (130 °C, 1.5 bar; 30 min to 4 h) are mild, and the pretreatment reagents (H 2 O 2 , FeCl 3 , and solvent) had low impact to environment. Using ferrimagnetic Fe 3 O 4 resulted in similar pretreatment efficiency and Fe 3 O 4 could be removed by filtration., Conclusions: A modified Fenton pretreatment of corncob in DMSO/water was developed. Up to 94% of the carbohydrate content of corncob was recovered as a saccharide solution simply by filtration. Such filtrate was directly applied to the subsequent enzymatic hydrolysis and where 92% of the corncob glucose content was obtained. The hydrolysate so obtained was directly applied to ethanol fermentation with good fermentability. The pretreatment method is simple, and the additives and solvents used have a low impact to the environment. This method provides the opportunity to substantially maximize the carbohydrate and solid lignin recovery of biomass with a comparatively green process, such that the efficiency of biorefinery as well as the bioethanol production process can be improved. The pretreatment is still relatively energy intensive and expensive, and further optimization of the process is required in large-scale operation.

Genistein, a plant isoflavone, is reported to have therapeutic potentials in multiple cancers, However, the molecular mechanism underlying promoting cell apoptosis in laryngeal cancer remains unclear. In this study, we report that miR-1469 was induced by genistein in laryngeal cancer. Elevated miR-1469 promoted cell apoptosis and inhibited Mcl1 expression. In addition, we also observed that tumor suppressor p53 was increased under genistein treatment. Elevation of p53 promoted miR-1469 expression, leading to miR-1469 increase and Mcl1 decrease. Therefore, our findings suggest that genistein can suppress laryngeal cancer cell survival through p53 -miR-1469-Mcl1pathway., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Caridina pseudodenticulata is a land-locked freshwater shrimp, which is endemic to North and West Taiwan. It is listed as Vulnerable under criteria A1ce in the IUCN Red List. Our study used mitochondrial DNA fragment sequences of the cytochrome oxidase subunit I (COI) gene to examine its genetic structure. In total, 204 sequences were analyzed from 22 populations, and all 39 haplotypes were identified. Our study (1) found that the genetic diversity within population of this species was similar to that of other land-locked freshwater prawn in Taiwan; (2) displayed that during glaciation, the Taiwan Strait was largely above water, an event which created opportunities for colonization Taiwan and dispersal widely; (3) showed that although the phylogenetic analysis showed the lack of a population genetic structure, the AMOVA and haplotypes distribution pattern revealed geographically divided; (4) indicated that C. pseudodenticulata could across to neighbor rivers through the mouths of rivers, which confluent with each other during floods.

Rheumatoid arthritis (RA) is an autoimmune disease in which T cells play an important role. Paeoniflorin-6-oxy-benzenesulfonate (CP-25) shows a strong anti-inflammatory and immunomodulatory effect in the joint of adjuvant arthritis (AA) rats, but the role of the spleen function is still unclear. The aim of this study was to research how CP-25 regulated spleen function of AA rats. Male Sprague-Dawley rats were administered with CP-25 (50 mg/kg) orally from day 17 to 29 after immunization. The spleen histopathological changes were analyzed by hematoxylin-eosin staining. G protein-coupled receptor kinases (GRKs) and prostaglandin receptor subtypes (EPs) were screened by Western blot and immunohistochemistry. The co-expression of GRK2 and EP2 as well as GRK2 and EP4 was measured by immunofluorescence and co-immunoprecipitation. The expression of GRK2 and EP4 in splenic T cells was further detected by immunofluorescence. CP-25 was found to relieve the secondary paw swelling, attenuate histopathologic changes, and downregulate GRK2, EP2 and EP4 expression in AA rats. Additionally, CP-25 not only downregulated the co-expression of GRK2 and EP4 but also downregulated GRK2, EP4 expression in splenic T cells of AA rats. From these results, we can infer that CP-25 play an anti-inflammatory and immune function by affecting the function of the splenic T cells.

The original version of this article contained mistakes, and the authors would like to correct them.

Tetrabutylammonium fluoride works as an effective organocatalyst for the cycloaddition between phenacylmalononitriles and electron-deficient olefins (having substituent groups of NO 2 , CHO, and COR), providing a facile synthetic route to versatile multifunctionalized cyclopentenes having an allylic quaternary carbon center bearing both cyano and carboxamide groups with high yields and high diastereoselectivity. Preliminary studies reveal that these functionalized cyclopentenes are convenient precursors for making α-cyano-functionalized cyclopentadienone oximes.

A one-pot and transition-metal-catalyst-free synthetic strategy to construct functionalized tellurophenes has been developed. Substituted 1,1-dibromo-1-en-3-ynes are smoothly converted to tellurophenes with telluride salts in high yield via a series of cascade reactions through reductive debromination, hydrotelluration, nucleophilic cyclization, and aromatization. Close inspection of the results clearly showed that the reactivity of in situ prepared telluride salts are significantly influenced by the polarity of the solvent system and the electronic nature of the substituent on the enyne substrate. This method reports the first direct synthesis of 3-aryltellurophenes in high yields at room temperature. This novel reaction strategy is also found to be a promising synthetic method for multisubstituted tellurophenes and selenophenes.

When a liquid becomes dynamically arrested, a gel, a repulsive glass, or an attractive glass state will form. Bonding and caging mechanisms decide their static structures and dynamic properties. To better understand their interplay, the competition between bonding and caging in a binary mixture of polystyrene core/poly( N-isopropylacrylamide) shell (CS) microgels and sulfonated polystyrene (PSS) particles is studied. CS microgels have short-range attraction above the volume phase transition temperature, whereas PSS species experiences relatively long-range electrostatic repulsion. Adding more PSS into the binary mixture will, of course, increase the total effective volume fraction but lead to different properties in gel or glass states. For instance, in gels, it increases the localization length and weakens the gel, whereas in glass, it decreases the localization length and strengthens the glass. This thus implies that the static and dynamic properties of gels are mainly controlled by bonding and those of both repulsive and attractive glasses are governed by caging. On the other hand, increasing the temperature will decrease the effective volume fraction because of the volume phase transition of the CS microgels. A discontinuous repulsive glass-to-liquid-to-gel transition can be observed when the PSS concentration is low, but a continuous repulsive glass-to-gel transition can also be observed with the increase of the PSS concentration. This may hint that glass transition and physical gelation share a similar mechanism, whereas the former has a longer relaxation time.

Chiao-Chuan Han, Tsair-Bor Yen, Nian-Cih Chen, and Mei-Chen Tseng (2017) Both Onychostoma barbatulum and O. alticorpus are primary freshwater fish in Taiwan. The former has been developed as an aquaculture species with high economic value, while the latter is a native endemic species in Taiwan. Understanding the cytogenetic information of these two species is necessary for their selected breeding, recovery, and management. In this study, Giemsa staining, silver-binding nucleolar organizer region (Ag-NOR), C-banding, and fluorescence in situ hybridization (FISH) with 18S ribosomal (r)DNA probes were used to analyze the cytogenetic characteristics. Results of Giemsa staining showed that the two Onychostoma species shared the same number of chromosomes, 2n = 50. Respective karyotype formulas of the female and male were 10 m + 22 sm + 10 st + 8 t and 11 m + 22 sm + 10 st + 7 t in O. barbatulum , and 14 m + 18 sm + 8 st + 10 t and 15 m + 18 sm + 8 st + 9 t in O. alticorpus . Karyotypes of both species showed a pair of heteromorphic chromosomes in male fish. Their sex determination should be the XX/XY system. Two pairs of Ag-NORs were found in O. barbatulum , but only one pair occurred in O. alticorpus . C-banding areas were observed on centromeres or telomeres of some chromosomes. FISH revealed different cytogenetic characters between these two species. The above cytogenetic information will contribute to species identification, population recovery, and advantages for breeding and management in the future.

Macrophages are myeloid immune cells which are strategically positioned throughout the body, where they engulf and degrade debris, dead cells, and foreign substances, and coordinating the inflammatory processes. Macrophages can be divided into two extreme subsets, classical activation (M1), and alternatively activation (M2). The symptoms and signs of rheumatoid arthritis (RA) would exacerbate with the increase in pro-inflammatory cytokines, whereas anti-inflammatory cytokines will alleviate the symptoms and signs of RA. This review, mainly discusses the effects of Notch, JNK and ERK signaling pathways on the regulation of macrophage polarization, and the effects of pro-inflammatory factors and/or anti-inflammatory cytokines produced by polarized macrophages in RA. Also, we will make an attempt to find out the importance of macrophage polarization in RA treatment as a drug target., (Copyright © 2017. Published by Elsevier B.V.)

Ginseng is a traditional Chinese medicine and has the extensive pharmacological activity. Ginsenosides are the major constituent in ginseng and have the unique biological activity and medicinal value. Ginsenosides have the good effects on antitumor, anti-inflammatory, antioxidative and inhibition of the cell apoptosis. Studies have showed that the major ginsenosides could be converted into rare ginsenosides, which played a significant role in exerting pharmacological activity. However, the contents of some rare ginsenosides are very little. So it is very important to find the effective way to translate the main ginsenosides to rare ginsenosides. In order to provide the theoretical foundation for the transformation of ginsenoside in vitro, in this paper, many methods of the transformation of ginsenoside were summarized, mainly including physical methods, chemical methods, and biotransformation methods.

Gelation transitions in a colloidal system, where there is a strong reversible attraction between small, soft microgels and large, hard spheres, are systematically investigated. Different from widely studied depletion attraction systems that are also two-component systems, the strong attraction between small solvent and large solute particles introduces bridging attractions between large solute particles. We conclusively demonstrate that the formation of physical gels at the intermediate volume fraction of our bridging attraction system follows more closely with the percolation line that is in stark contrast to what is observed in depletion attraction systems, where the gelation transition is related with the frustrated spinodal separation, not a purely kinetic phenomenon. Our results introduce a different way to control gelation transitions in spherical colloidal systems, and imply that people need to be prudent when generalizing the physical picture of the gelation transitions obtained from systems with different origins of effective attraction as the solvent molecule may play important roles.

G protein-coupled receptor kinase 2 (GRK2) is a key member of the G protein-coupled receptor kinase (GRK) family. GRK2 activity is regulated by the C-terminus of GRK2 which contains a plekstrin homology domain and the N-terminus of GRK2 which contains the RGS homology domain with binding sites for several proteins and lipids such as G protein-coupled receptors (GPCRs), G protein, phospholipase C, phosphatidylinositol 4,5-bisphosphate, extracellular signal‑regulated kinase, protein kinase A and Gβγ. GRK2 phosphorylates the GPCR and enhances the affinity of binding to arrestins, which uncouple the receptors from G proteins, and target the receptors for desensitization and internalization. GRK2 also regulates non‑GPCR desensitization and internalization by phosphorylation, and is important in maintaining the balance between the receptors and signal transduction. Previous findings have indicated that the upregulation of GRK2 in heart failure enhances dysfunctional adrenergic signaling and myocyte death. Collagen-induced arthritis induces the upregulation of GRK2 expression in fibroblast-like synoviocytes. In this review, we discussed the evidence for the association between altered GRK2 levels and various diseases, which suggests that GRK2 may be an effective drug target for preventing and treating heart failure, hypertension and inflammatory disease.

In this study, the attraction between large hard polystyrene (PS) spheres is studied by using three types of small microgels as bridging agents. One is a purely soft poly(N-isopropylacrylamide) (PNIPAM) microgel, the other two have a non-deformable PS hard core surrounded by a soft PNIPAM shell but are different in the core-shell ratio. The affinity for bridging the large PS spheres is provided and thus affected by the PNIPAM constituent in the microgels. The bridging effects caused by the microgels can be indirectly incorporated into their influence on the effective attraction interaction between the large hard spheres, since the size of the microgels is very small in comparison to the size of the PS hard spheres. At a given volume fraction of large PS spheres, they behave essentially as hard spheres in the absence of small microgels. By gradually adding the microgels, the large spheres are connected to each other through the bridging of small particles until the attraction strength reaches a maximum value, after which adding more small particles slowly decreases the effective attraction strength and eventually the large particles disperse individually when saturated adsorption is achieved. The aggregation and gelation behaviors triggered by these three types of small microgels are compared and discussed. A way to tune the strength and range of the short-range attractive potential via changing the softness of bridging microgels (which can be achieved either by using core-shell microgels or by changing the temperature) is proposed.

Basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF) produced by hepatocellular carcinoma (HCC) cells are responsible for the growth of HCC cells. Accumulating evidence shows that insulin-like growth factor-binding protein-3 (IGFBP-3) suppresses HCC cell proliferation in both IGF-dependent and independent manners. It's unknown, however, whether treatment with exogenous IGFBP-3 inhibits bFGF and PDGF production in HCC cells. The present study demonstrates that IGFBP-3 suppressed IGF-1-induced bFGF and PDGF expression while it does not affect their expression in the absence of IGF-1. To delineate the underlying mechanism, western-blot and RT-PCR assays confirmed that the transcription factor early growth response protein 1 (EGR1) is involved in IGFBP-3 regulation of bFGF and PDGF. IGFBP-3 inhibition of type 1 insulin-like growth factor receptor (IGF1R), ERK and AKT activation is IGF-1-dependent. Furthermore, transient transfection with constitutively activated AKT or MEK partially blocks the IGFBP-3 inhibition of EGR1, bFGF and PDGF expression. In conclusion, these findings suggest that IGFBP-3 suppresses transcription of EGR1 and its target genes bFGF and PDGF through inhibiting IGF-1-dependent ERK and AKT activation. It demonstrates the importance of IGFBP-3 in the regulation of HCC cell proliferation, suggesting that IGFBP-3 could be a target for the treatment of HCC., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Unlabelled: Phosphatidylinositol-3 kinases (PI3K)-Protein kinase B (Akt)-mammalian target of rapamycin (mTOR) pathway plays an important role in the synthesis and secretion of triacylglycerol. However, the mechanism of PI3K-Akt-mTOR pathway in regulating lipid metabolism of goose liver was poorly understood. The purpose of this study was to determine how PI3K-Akt-mTOR pathway regulating lipid metabolic homeostasis in goose hepatocytes. Goose primary hepatocytes were treated with different PI3K-Akt-mTOR signal inhibitors (LY294002, rapamycin and NVP-BEZ235) for 24 h. The results showed that these inhibitors evidently inhibited PI3K-Akt-mTOR downstream signaling. Meanwhile, these PI3K-Akt-mTOR inhibitors reduced intracellular lipid accumulation, decreased the mRNA expression and protein content of genes involved in the de novo fatty acid synthesis, while increased the transcriptional and protein level of key factors involved in fatty acid oxidation and very low density lipoprotein (VLDL) assembly and secretion., Conclusion: These findings suggested that the reduction of lipids accumulation induced-by inhibiting PI3K-Akt-mTOR pathway was closely linked to the decrease of lipogenesis, the increase of fatty acids oxidation, and the increase of VLDL assembly and secretion in goose hepatocytes.

PI3K-Akt-mTOR signaling pathway is associated with endoplasmic reticulum (ER) stress. However, it is not clear how this signaling pathway affects the ER stress. The present study aimed to determine whether the PI3K-Akt-mTOR signaling pathway regulates tunicamycin (TM)-induced increases in mRNA levels of genes involved in the ER stress, to help elucidate the mechanism by which this pathway affects the ER stress in primary goose hepatocytes. Primary hepatocytes were isolated from geese and cultured in vitro. After 12 h in a serum-free medium, the hepatocytes were incubated for 24 h in a medium with either no addition (control) or with supplementation of TM or TM together with PI3K-Akt-mTOR signaling pathway inhibitors (LY294002, rapamycin, NVP-BEZ235). Thereafter, the expression levels of genes involved in the ER stress (BIP, EIF2a, ATF6, and XBP1) were assessed. The results indicated that the mRNA level of BIP was up-regulated in 0.2, 2, and 20 μM TM treatment group (P < 0.05), whereas the mRNA levels of EIF2a, ATF6, and XBP1 were up-regulated in the 2 μM TM treatment group (P < 0.05). However, the TM mediated induction of mRNA levels of genes involved in the ER stress (BIP, EIF2a, ATF6, and XBP1) was down-regulated after the treatment with PI3K-Akt-mTOR pathway inhibitors (LY294002, NVP-BEZ235, and rapamycin). Therefore, our results strongly suggest that the PI3K-Akt-mTOR signaling pathway might be involved in the down-regulation of the TM-induced ER stress in primary goose hepatocytes., Competing Interests: The authors declare no conflict of interest.

Two types of colloidal particles, which are nearly the same in chemical composition but carry opposite surface charges, are mixed in water. Depending on the relative proportion of the oppositely charged particles, the process of aggregation leads to the formation of discrete clusters of various sizes in dilute dispersions, and to the development of particle gel networks in more concentrated systems. Due to the significant difference in the absolute values of surface charges (negative particle: -48 mV, positive particle: +24 mV), the phase separation and the gelation behaviors are asymmetric with respect to the mixing ratio. Mixtures with excess negative particles are more stable, while mixtures with excess positive particles are easily affected by phase separation. The hetero-aggregation triggered by the addition of microscopically large macro-ions is similar to what is often observed in a mono-component charged colloidal system, i.e., phase separation occurs through addition of small electrolyte ions. Within the concentration region investigated here, it is clear that the gel line is buried inside the phase separation region. Gelation occurs only when the number and size of the clusters are large and big enough to connect up into a space-spanning network. Our results indicate that, in this binary mixture of oppositely charged colloids, although the interaction between unlike species is attractive and that between like species is repulsive, the onset of gelation is in fact governed by the equilibrium phase separation, as in the case of purely attractive systems with short-range isotropic interaction.

While mass spectrometry (MS) plays a key role in proteomics research, characterization of membrane proteins (MP) by MS has been a challenging task because of the presence of a host of interfering chemicals in the hydrophobic protein extraction process, and the low protease digestion efficiency. We report a sample preparation protocol, two-phase separation with Triton X-100, induced by NaCl, with coomassie blue added for visualizing the detergent-rich phase, which streamlines MP preparation for SDS-PAGE analysis of intact MP and shot-gun proteomic analyses. MP solubilized in the detergent-rich milieu were then sequentially extracted and fractionated by surface-oxidized nanodiamond (ND) at three pHs. The high MP affinity of ND enabled extensive washes for removal of salts, detergents, lipids, and other impurities to ensure uncompromised ensuing purposes, notably enhanced proteolytic digestion and down-stream mass spectrometric (MS) analyses. Starting with a typical membranous cellular lysate fraction harvested with centrifugation/ultracentrifugation, MP purities of 70%, based on number (not weight) of proteins identified by MS, was achieved; the weight-based purity can be expected to be much higher.

G protein-coupled receptor kinase 2 (GRK2) is a serine/threonine kinase that is involved in a variety of important signaling pathways and alternation of GRK2 protein level or activity causes diseases such as heart failure, rheumatoid arthritis, and obesity. However, the role and mechanism of GRK2 in hepatocellular carcinoma (HCC) progression is not fully investigated. In this study we found that GRK2 plays an inhibitory role in IGF1-induced HCC cell proliferation and migration. Overexpression of GRK2 causes a decrease in early growth response-1 (EGR1) expression, while knockdown of GRK2 leads to marked increase in EGR1 expression in the treatment of IGF1. Through co-immunoprecipitation and western blot assay, we confirmed that GRK2 can interact with insulin-like growth factor 1 receptor (IGF-1R) and inhibits IGF1-induced activation of IGF1R signaling pathway. Silencing EGR1 attenuates GRK2 overexpression-caused inhibition of cell proliferation, tumor colony number and migration activity, while overexpressing of EGR1 restores the anti-proliferative and migratory effect by GRK2 overexpression in HCCLM3 cells. Collectively, these results suggest that GRK2 may inhibit IGF1-induced HCC cell growth and migration through downregulation of EGR1 and indicate that enforced GRK2 may offer a potential therapeutic approach against HCC.

In this study, the complete mitogenome sequence of cyprinid fish, Holland's spinibarbel Spinibarbus hollandi Oshima (1919) (Cypriniformes, Cyprinidae, Barbinae) has been amplified and sequenced by employing long polymerase chain reaction method. The mitogenome, consisting of 16,523 base pairs (bp), had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes, and a non-coding control region (CR). CR of 867 bp length is located between tRNA(Pro) and tRNA(Phe). The overall base composition of S. hollandi is 31.87% for A, 26.56% for C, 25.89% for T, and 15.68% for G, with a slight AT bias of 57.76%. The complete mitogenome may provide rather essential and important DNA molecular data for further phylogenetic analysis for not only congeneric species but also higher different taxa of Cyprinid fishes.

Periplasmic expression of soluble proteins in Escherichia coli not only offers a much-simplified downstream purification process, but also enhances the probability of obtaining correctly folded and biologically active proteins. Different combinations of signal peptides and target proteins lead to different soluble protein expression levels, ranging from negligible to several grams per litre. Accurate algorithms for rational selection of promising candidates can serve as a powerful tool to complement with current trial-and-error approaches. Accordingly, proteomics studies can be conducted with greater efficiency and cost-effectiveness. Here, we developed a predictor with a two-stage architecture, to predict the real-valued expression level of target protein in the periplasm. The output of the first-stage support vector machine (SVM) classifier determines which second-stage support vector regression (SVR) classifier to be used. When tested on an independent test dataset, the predictor achieved an overall prediction accuracy of 78% and a Pearson's correlation coefficient (PCC) of 0.77. We further illustrate the relative importance of various features with respect to different models. The results indicate that the occurrence of dipeptide glutamine and aspartic acid is the most important feature for the classification model. Finally, we provide access to the implemented predictor through the Periscope webserver, freely accessible at http://lightning.med.monash.edu/periscope/.

TOX3 is a newly identified gene that has been observed to correlate with breast cancer by genome-wide association studies (GWAS) in recent years. In addition, it has been noted that single-nucleotide polymorphisms (SNPs) in the TOX3 gene have a strong correlation with estrogen receptor (ER)-positive tumors. However, the role of TOX3 in breast carcinoma development is still unclear. There are limited studies on the subject of TOX3 mRNA expression in breast tumors and little information on the variation of TOX3 protein expression in relation to the clinical pathological features in breast cancer and healthy tissues. In this study, we characterize the protein expression of TOX3 in breast tumors with respect to various clinical and pathological characteristics and explore the correlation between TOX3 protein expression and ER-positive tumors. A breast cancer tissue microarray containing 267 human breast tumors and 25 healthy controls, breast cancer cell lines (ZR-75-1, MDA-MB-231, MCF-7 and Bcap-37) with positive or negative ER expression, tumor tissues and matched controls were used to analyze the protein expression levels of TOX3 by immunohistochemistry, western blot analysis and quantitative polymerase chain reaction. Among the 267 breast tumor specimens, ER expression was detected in 66 tumor tissues. The expression levels of TOX3 increased in breast carcinoma tissue compared with controls, and were higher in advanced carcinoma (T3 and T4), lymph node metastases tissues (N2) and stage III tissues. Furthermore, TOX3 protein expression was more intense in ER-positive tumors, but did not demonstrate a statistical significance. However, it was significantly increased in ER-positive breast cancer cell lines (ZR-75-1, MCF-7 and Bcap-37) compared with the MDA-MB-231 cell line, which had ER-negative expression. Our findings provide support to the hypothesis that TOX3 has a strong correlation with the development of breast cancer. The current study is likely to assist in investigating the mechanisms involved in breast cancer development.

Is domain-general memory updating ability predictive of calculation skills or are such skills better predicted by the capacity for updating specifically numerical information? Here, we used multidigit mental multiplication (MMM) as a measure for calculating skill as this operation requires the accurate maintenance and updating of information in addition to skills needed for arithmetic more generally. In Experiment 1, we found that only individual differences with regard to a task updating numerical information following addition (MUcalc) could predict the performance of MMM, perhaps owing to common elements between the task and MMM. In Experiment 2, new updating tasks were designed to clarify this: a spatial updating task with no numbers, a numerical task with no calculation, and a word task. The results showed that both MUcalc and the spatial task were able to predict the performance of MMM but only with the more difficult problems, while other updating tasks did not predict performance. It is concluded that relevant processes involved in updating the contents of working memory support mental arithmetic in adults.

Linear rheological properties and yielding behavior of polystyrene core and poly (N-isopropylacrylamide) (PNIPAM) shell microgels were investigated to understand the transition from repulsive glass (RG) to attractive glass (AG) and the A3 singularity. Due to the volume phase transition of PNIPAM in aqueous solution, the microgel-microgel interaction potential gradually changes from repulsive to attractive. In temperature and frequency sweep experiments, the storage modulus (G') and loss modulus (G″) increased discontinuously when crossing the RG-to-AG transition line, while G' at low frequency exhibited a different volume fraction (Φ) dependence. By fitting the data of RG and AG, and then extrapolating to high volume fraction, the difference between RG and AG decreased and the existence of A3 singularity was verified. Dynamic strain sweep experiments were conducted to confirm these findings. RG at 25 °C exhibited one-step yielding, whereas AG at 40 °C showed a typical two-step yielding behavior; the first yielding strain remained constant and the second one gradually decreased as the volume fraction increased. By extrapolating the second yield strain to that of the first one, the predicted A3 singularity was at 0.61 ± 0.02. At 37 °C, when Φeff = 0.59, AG showed one step yielding as the length of the attractive bond increased. The consistency and agreement of the experimental results reaffirmed the existence of A3 singularity, where the yielding behavior of RG and AG became identical.

Onychostoma barbatulum and O. alticorpus, two primarily freshwater cyprinid fish, have similar morphological characters and partially overlapping ecological habitats. In order to explore the genetic differences between these two species, chromosomal characteristics and genetic variations were examined by fluorescence in situ hybridization (FISH) of 5S rDNA and cytochrome (Cyt) b gene analysis. Ten specimens of O. barbatulum and O. alticorpus were collected from the Nanzihsian Stream in southern Taiwan. FISH revealed that the 5S rDNA loci of O. barbatulum and O. alticorpus were found at a pericentromeric and subtelomeric position, respectively, in a pair of submetacentric chromosomes. Cyt b genes were amplified and sequenced from five individuals of each species. Intraspecific genetic distances ranged from 0.001-0.004 in O. barbatulum and from 0.001-0.006 in O. alticorpus. Genetic distances between these two species ranged from 0.132-0.142. The phylogenetic tree showed these two species are not sister species. In conclusion, FISH cytogenetic information and Cyt b gene analyses indicated that these two species have significantly different genetic characteristics; nevertheless, their morphological similarities may be due to environmental adaptation.

The state transition from gel to glass is studied in a biphasic mixture of polystyrene core/poly(N-isopropylacrylamide) shell (CS) microgels and sulfonated polystyrene (PSS) particles. At 35 °C, the interaction between CS microgels is due to short-range van der Waals attraction, while that between PSS particles is from long-range electrostatic repulsion. During the variation of the relative ratio of the two species at a fixed apparent total volume fraction, the mixture exhibits a gel-to-defective gel-to-glass transition. When small amounts of PSS are introduced into the CS gel network, some of them are kinetically trapped, causing a change in its fractal structure, and act as defects to weaken the macroscopic gel strength. An increase of the PSS content in the mixture promotes the switch from the gel to the defective gel, e.g., the typical two-step yielding gel merges into one-step yielding. This phenomenon is an indication that inter-cluster bond breakage coincides with intra-cluster bond fracture. As the relative volume fraction of PSS exceeds a critical threshold, the gel network can no longer be formed; hence, the mixture exhibits characteristics of glass. A state diagram of the biphasic mixture is constructed, and the landscapes of the different transitions will be described in future studies.

Acetylene (HCCH) has a long history as a mechanism-based enzyme inhibitor and is considered an active-site probe of the particulate methane monooxygenase (pMMO). Here, we report how HCCH inactivates pMMO in Methylococcus capsulatus (Bath) by using high-resolution mass spectrometry and computational simulation. High-resolution MALDI-TOF MS of intact pMMO complexes has allowed us to confirm that the enzyme oxidizes HCCH to the ketene (C2H2O) intermediate, which then forms an acetylation adduct with the transmembrane PmoC subunit. LC-MS/MS analysis of the peptides derived from in-gel proteolytic digestion of the protein subunit identifies K196 of PmoC as the site of acetylation. No evidence is obtained for chemical modification of the PmoA or PmoB subunit. The inactivation of pMMO by a single adduct in the transmembrane PmoC domain is intriguing given the complexity of the structural fold of this large membrane-protein complex as well as the complicated roles played by the various metal cofactors in the enzyme catalysis. Computational studies suggest that the entry of hydrophobic substrates to, and migration of products from, the catalytic site of pMMO are controlled tightly within the transmembrane domain. Support of these conclusions is provided by parallel experiments with two related alkynes: propyne (CH3CCH) and trifluoropropyne (CF3CCH). Finally, we discuss the implication of these findings to the location of the catalytic site in pMMO., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In the present study, we isolated preadipocytes from the adipose tissue of Peking duck and subsequently cultured them in vitro. Cell counting kit-8 assay was employed to establish the growth curve of duck primary preadipocytes. Meanwhile, after the cells reaching full confluency, they were induced to differentiate into mature adipocytes by the addition of a cocktail containing dexamethasone, insulin, 3-isobutyl-1-methylxanthine, and oleic acid for 8 days. Successful differentiation was demonstrated by the development of lipid droplets and the expression of key marker genes including peroxisome proliferator-activated receptor-γ (PPARγ), CCAAT/enhancer binding protein-α (CEBP/α) and adipocyte fatty acid-binding protein (FABP4). Our results showed that duck primary preadipocytes began to adhere 12 h after seeding as short spindle shapes or litter triangles, which grew quickly 3 days post attachment and maintained stable after day 7. After 8 days the preadipocytes were induced to differentiate into mature adipocytes, which were stained red by oil red O. Additionally, it showed that during preadipocyte differentiation PPARγ mRNA was highly expressed at day 3, while CEBP/α and FABP4 mRNA peaked at day 5 and 8, respectively. These results indicate that we have successfully isolated and cultured Peking duck preadipocytes and successfully induced them to differentiate into mature adipocytes. This work could lay a foundation for further research into waterfowl adipogenesis.

The present work investigated the influence of organoclay (organo-montmorillonite, OMMT) on the phase separation behavior and morphology evolution of solution polymerized styrene-butadiene rubber (SSBR)/low vinyl content polyisoprene (LPI) blends with rheological methodology. It was found that the incorporation of OMMT not only reduced the droplet size of the dispersion phase, slowed down the phase separation kinetics, also enlarged the processing miscibility window of the blends. The determination on the wetting parameters indicated that due to the oscillatory shear effect, the OMMT sheets might localize at the interface between the two phases and act as compatibilizer or rigid barrier to prevent domain coarsening, resulting in slow phase separation kinetics, small droplet size, and stable morphology. The analysis of rheological data by the Palierne model provided further confirmation that the addition of OMMT can decrease the interfacial tension and restrict the relaxation of melt droplets. Therefore, a vivid "sea-fish-net" model was proposed to describe the effect of OMMT on the phase separation behavior of SSBR/LPI blends, in which the OMMT sheets acted as the barrier (net) to slow down the domain coarsening/coalescence in phase separation process of SSBR/LPI blends.

Placing a physical barrier between the injured site and the adjacent tissues is a very common and highly effective approach to prevent abdominal adhesions in these days. A biodegradable trilayered barrier was fabricated to prevent formation of abdominal adhesions, in which a poly(lactide-co-glycolide)/poly(lactide)-b-poly(ethylene glycol) (PLGA/PLA-b-PEG) electrospun layer was sandwiched between layers of carboxymethyl chitosan (CMCS) sponge. The hydrophilic CMCS sponge layers with glycerin (GL) could adhere to the surface of wound easily, and present great hemostatic capability. The mechanism of the formation of adhesion related to blood clots acting with fibroblast cells was evaluated in detail. The blood clot acted as a "medium" inducing the fibroblast cells growth and proliferation, but had no special attraction on epithelial cells. CMCS sponge layer took away the blood clots during the swelling and dissolution stages. The electrospun layer promoted the growth of epithelial cells, but exhibited inhibition on the adhesion and spread of fibroblast cells, which ensured excellent effect of adhesion prevention. Evaluated by a rat model of sidewall defect-bowel abrasion, significant reductions of postoperative adhesion in its level and occurrence were observed in animals treated by the trilayered barrier.

Complexes [Cu(I)(2,4-dimethylphenoxy)2](-) (A) and [Cu(II)(2,4-dimethylphenoxy)2(p-tolyl)](-) (B) were observed by in situ electrospray ionization mass spectrometry (ESI-MS) analysis of the ligand free copper(I)-catalyzed C-O coupling reaction using Cs2CO3 under the catalytic reaction conditions indicating that they could be intermediates in the reaction. The radical scavenger cumene retarded the reaction. Catalytic cycles involving a free radical path are proposed based on these observations.

The complete mitochondrial genome of Zacco platypus (Cypriniformes, Cyprinidae), which has broader distribution range and diverse genetic structure than other species under the genus Zacco, was first determined in this study. The mitochondrial genome is 16,612 base pairs (bp) in length, encoding 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs and 1 non-coding control region. Its gene arrangement and translation direction were identical to those of other typical vertebrate. Control region (D-Loop), of 929 bp lengths long, is located between tRNA(Pro) and tRNA(Phe). The overall base composition of the heavy strand shows T 27.02%, C 26.23%, A 28.94% and G 17.82%, with a slight AT bias of 55.95%.

Background: Rapid and accurate discrimination of Mycobacterium avium from other mycobacteria is essential for appropriate therapeutic management and timely intervention for infection control. However, routine clinical identification methods for M. avium are both time consuming and labor intensive. In the present study, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to identify specific cellular protein pattern for rapid identification of M. avium isolates., Methods: A total of 40 clinically relevant Mycobacterium strains comprising 13 distinct species were enrolled for the MALDI-TOF MS identification. A 10-minute extraction-free examination procedure was set up to obtain mass spectral fingerprints from whole bacterial cells., Results: The characteristic mass spectral peak patterns in the m/z (mass/charge ratio) range of 5-20 kDa can be obtained within 10 minutes. The species-specific mass spectra for M. avium is identified and can be differentiated from as Mycobacterium strains. This technique shortens and simplifies the identification procedure of MALDI-TOF MS and may further extend the mycobacterial MALDI-TOF MS database., Conclusion: Simplicity and rapidity of identification procedures make MALDI-TOF MS an attractive platform in routine identification of mycobacteria. MALDI-TOF MS is applicable for rapid discrimination of M. avium from other Mycobacterium species, and shows its potential for clinical application., (Copyright © 2013. Published by Elsevier B.V.)

In this study, mixed suspensions of large hard polystyrene microspheres and small soft poly(N-isopropylacrylamide) microgels are used as model systems to investigate the static and viscoelastic properties of suspensions which go through liquid to gel transitions. The microgels cause short-range attraction between microspheres through the bridging and depletion mechanism whose strength can be tuned by the microgel concentration. Rheological measurements are performed on suspensions with the volume fraction (Φ) of microspheres ranging from 0.02 to 0.15, and the transitions from liquid-like to solid-like behaviors triggered by the concentration of microgels are carefully identified. Two gel lines due to bridging attraction under unsaturated conditions are obtained. Ultra-small angle neutron scattering is used to probe the thermodynamic properties of suspensions approaching the liquid-solid transition boundaries. Baxter's sticky hard-sphere model is used to extract the effective inter-microsphere interaction introduced by the small soft microgels. It is found that the strength of attraction (characterized by a single stickiness parameter τ) on two gel lines formed by bridging is very close to the theoretical value for the spinodal line in the τ-Φ phase diagram predicted by Baxter's model. This indicates that the nature of the gel state may have the same thermodynamic origins, independent of the detailed mechanism of the short-range attraction. The relationship between the rheological criterion for the liquid-solid transition and the thermodynamic criterion for the equilibrium-nonequilibrium transition is also discussed.

Background: The root bark of Aralia is a rich source of bioactive components that may improve glycemic control and lipid status. In this study, 148 patients with type 2 diabetes mellitus (T2DM) were assigned randomly to receive either glipizide alone or glipizide plus Aralia root bark extract (ARBE) for 8 weeks to test the effects of ARBE plus glipizide therapy on glycemic control and lipid profiles in these patients., Results: Levels of HbA1c, fasting plasma glucose (FPG) and 2 h postprandial plasma glucose (2-h PPG) in both groups significantly decreased from baseline. Glycated hemoglobin (HbA1c) decreased marginally significantly in participants taking glipizide plus ARBE compared with the glipizide group (P = 0.06). Participants in the combination group had significant decreases in total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), and the between-group difference achieved statistical significance for LDL-C (P = 0.04). Reduction in HbA1c in the combination group was significantly associated with changes in TC (r = 0.32; P = 0.006) and LDL-C (r = 0.34; P = 0.005), and the change in FPG was inversely correlated with LDL-C reduction (r = 0.34; P = 0.004)., Conclusions: In patients with T2DM, combination therapy with glipizide and ARBE resulted in moderately lowering HbA1c and LDL-C levels compared with glipizide alone., (© 2014 Society of Chemical Industry.)

The understanding of protein-folding mechanisms is often considered to be an important goal that will enable structural biologists to discover the mysterious relationship between the sequence, structure and function of proteins. The ability to predict protein-folding rates without the need for actual experimental work will assist the research work of structural biologists in many ways. Many bioinformatics tools have emerged in the past decade, and each has showcased different features. In this article, we review and compare eight web-based prediction tools that are currently available and that predominantly predict the protein-folding rate. The prediction performance, usability and utility, together with the prediction tool development and validation methodologies for these tools, are critically reviewed. This article is presented in a comprehensible manner to assist readers in the process of selecting the most appropriate bioinformatics tools to meet their needs., (© The Author 2014. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.)

The complete mitochondrial genome of the Cyprinid fish Gobiobotia intermedia (Cypriniformes, Cyprinidae) was determined. The complete mitogenome sequence has 16,608 bp and contains the usual 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA (tRNA) genes and a non-coding control region, as those found in other vertebrates, with the gene order identical to that of typical vertebrates. The overall base composition of the heavy strand shows T 26.08%, C 27.25%, A 27.57% and G 19.11%, apparently with a slight AT bias.

Gelation and glass transition in a mixed suspension of polystyrene (PS) microsphere and poly(N-isopropylacrylamide) (PNIPAM) microgel were studied as a function of the total colloid volume fraction and mixing ratio of these two components. The PNIPAM microgel, which is adsorbable on the PS microsphere surface, can induce bridging or stabilizing effect between microspheres depending on whether the volume fraction of microgel (ΦMG) is smaller or larger than the saturated adsorption concentration (Φ*MG) for a given volume fraction of the microsphere (ΦMS). Φ*MG is in a linear relationship with ΦMS, and the value of ΦMG/Φ*MG can be taken as an approximate measure of surface coverage. A state diagram of gelation and glass transition is constructed with the short-ranged attractive interaction, resulting from the well-defined bridging bonding. Keeping ΦMG/Φ*MG = 0.20 and increasing ΦMS from 0.25 to 0.55, the mixed suspension transforms from a bridging gel into an attractive glass; moreover, while keeping ΦMS = 0.45 and increasing ΦMG/Φ*MG from 0.20 to 1.2, the mixed suspension changes from a bridging gel into an attractive glass, and then to a repulsive glass. The bridging effect and the cage effect can be distinguished by the yielding behaviors in rheological measurements. In the nonlinear dynamic rheological experiments, one-step yielding, corresponding to the disconnecting of bridge network, is observed in the bridging gel, and one-step yielding, corresponding to the breaking of cage, is observed in the repulsive glass. However, a two-step yielding behavior is found in the bridging-induced attractive glass, which is attributed to the bridging effect of microgels and the caging effect of the dense environment.

The solubility of recombinant protein expressed in Escherichia coli often represents the production yield. However, up-to-date, instances of successful production of soluble recombinant proteins in E. coli expression system with high yield remain scarce. This is mainly due to the difficulties in improving the overall production capacity, as most of the well-established strategies usually involve a series of trial and error steps with unguaranteed success. One way to concurrently improve the production yield and minimize the production cost would be incorporating the potency of bioinformatics tools to conduct in silico studies, which forecasts the outcome before actual experimental work. In this article, we review and compare seven prediction tools available, which predict the solubility of protein expressed in E. coli, using the following criteria: prediction performance, usability, utility, prediction tool development and validation methodologies. This comprehensive review will be a valuable resource for researchers with limited prior experience in bioinformatics tools. As such, this will facilitate their choice of appropriate tools for studies related to enhancement of intracellular recombinant protein production in E. coli., (© The Author 2013. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.)

The liquid-gel-liquid transition tuned by increasing concentration of linear and hyperbranched polyethyleneimine in suspension of silica colloids, and the accompanying shear-thickening phenomena, were investigated by rheological measurements. The influence from linear and hyperbranched polymer conformation and from different size-ratio between particle and polymer on the rheological properties of suspensions flocculated by absorbing polyelectrolyte were considered. Charge neutralization and bridging mechanism are the main reasons for the flocculation of silica colloid in this study. Because of charge reversal, the irreversible bridges are turned into flexible reversible bridges with increasing adsorption amount of oppositely charged polymer, which leads to an abrupt transition from gel to liquid. Over a narrow composition range, around the gel to liquid transition region, shear-thickening flow is observed. It is found that, for given particle volume fraction, the composition region exhibiting shear-thickening for mixed suspension with linear polyethyleneimine is broader than that for mixed suspension with hyperbranched polyethyleneimine, and the onset of shear-thickening depends only on size-ratio, regardless of the actual size of particle and polymer in the range of this study. The relationship between the gel to liquid transition and shear-thickening was discussed.

A series of microgel particles composed of a polystyrene (PS) core and a thermo-sensitive poly(N-isopropylacrylamide) (PNIPAM) shell with different shell thicknesses were investigated to elucidate the effect of microgel softness on its shear thickening behavior. Since the softness of the microgels increases with decreasing temperature through the volume phase transition effect of PNIPAM shell, the measured softness parameter, n, which is derived from the Zwanzig-Mountain equation, was used to measure and describe the combined influences of temperature and shell thickness. Confocal microscopy is used to investigate the interaction potential between microgel particles with different softness parameters. According to the obtained results, the softness parameter can provide an estimate for the shear thickening behavior of microgel suspensions, at least semi-quantitatively.

An efficient method for modifying the surface of detonation nanodiamonds (5 and 100 nm) with thiol groups (-SH) by using an organic chemistry strategy is presented herein. Thiolated nanodiamonds were characterized by spectroscopic techniques, and the atomic percentage of sulfur was analyzed by elemental analysis and X-ray photoelectron spectroscopy. The conjugation between thiolated nanodiamonds and gold nanoparticles was elucidated by transmission electron microscopy and UV-vis spectrometry. Moreover, the material did not show significant cytotoxicity to the human lung carcinoma cell line and may prospectively be applied in bioconjugated technology. The new method that we elucidated may significantly improve the approach to surface modification of detonation nanodiamonds and build up a new platform for the application of nanodiamonds.

Rheological measurements are utilized to examine the yielding behavior of a polystyrene (PS) core and poly(N-isopropylacrylamide) (PNIPAM) shell microgel system with varying shell/core ratio. For a shell/core ratio of 0.15 at high concentrations, the suspensions show a typical hard sphere (HS) yielding response where the loss modulus (G″) exhibits a single peak due to cage breaking. As a result of tighter cages and less cage distortion prior to yielding, the peak location of G″ decreases with volume fraction. For a shell/core ratio of 1.10, which behaves like a soft jammed glass at high concentration, the suspensions exhibit a one-step yielding behavior similar to that of HS glass. However, the location of the peak in G″ increases with volume fraction, demonstrating the important role of particle deformation in the breakage of cages. For an intermediate shell/core ratio of 0.34, the system displays a two-step yielding behavior, as observed in previous reports for attractive glasses. By increasing the volume fraction, the strain of the first peak increases while the second one decreases. In addition, as the effective volume fraction increases to 112%, the two peaks merge into one broad peak. It is demonstrated that the first peak of G″ is due to deformation of the shell, and the second peak of G″ is attributed to cage breaking as a result of the cores colliding with each other. Combining these results, a yielding state diagram from typical HS to soft jammed glass is demonstrated.

Complex [K3(phen)8][Cu(NPh2)2]3 (1, phen = phenanthroline) was isolated from the catalytic C-N cross coupling reaction based on the CuI-phen-tBuOK catalytic system. Complex 1 can react with 4-iodotoluene to give 4-methyl-N,N-diphenylaniline (3a) in 50% yield (based on all available NPh2(-) ligands of complex 1). In addition, 1 can also work as an effective catalyst for the C-N coupling reactions under the same reaction conditions, indicating that 1 may be an effective intermediate of the catalytic system. In the presence of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), a radical scavenger, the stoichiometric reaction between complex 1 and 4-iodotoluene was significantly quenched to give a low yield of 12%. The results suggest that the radical path dominates in the reaction, with (phen)KNPh2 as the possible radical source. The structures of 1 and (phen)KNPh2 were both determined by single crystal X-ray diffraction studies.

Coarsening is a general phenomenon in phase separating mixtures. In this study, we report a hierarchical coarsening at different length scales. Dispersed domains grew by direct combination of two/three small ones while some small domains can survive for a long time. The small angle laser light scattering showed that the scattered intensity exhibited multiple "decay-growth" transitions in the coarsening process. The evolution of the main peak gave a characteristic power law index of about -3/4, which is much faster than the -1/3 relationship from the traditional theories. We propose that relaxation and hydrodynamic flow play important roles in this process.

The purpose of this meta-analysis was to evaluate the relationship between blood lutein and zeaxanthin concentration and the risk of age-related cataract (ARC). MEDLINE, EMBASE, ISI and Cochrane Library were searched to identify relevant studies up to April 2013. Meta-analysis was conducted to obtain pooled relative risks (RRs) for the highest-versus-lowest categories of blood lutein and zeaxanthin concentrations. One cohort study and seven cross-sectional studies were included in the meta-analysis. There were significant inverse associations between nuclear cataract and blood lutein and zeaxanthin concentrations, with the pooled RRs ranging from 0.63 (95% confidence interval (CI): 0.49, 0.77) for zeaxanthin to 0.73 (95% CI: 0.59, 0.87) for lutein. A stronger association between nuclear cataract and blood zeaxanthin might be noted for the studies conducted in the European Nations. Blood lutein and zeaxanthin were also noted to lead towards a decrease in the risk of cortical cataract and subcapsular cataract; however, these pooled RRs were not statistically significant, with the exception of a marginal association between lutein and subcapsular cataract. Our results suggest that high blood lutein and zeaxanthin are significantly associated with a decrease in the risk of nuclear cataract. However, no significant associations were found for ARC in other regions of the lens.

In this work, we used poly(L-lactide)-block-poly(ethylene glycol) (PLLA-b-PEG) copolymer thick films to investigate the effect of crystallization on surface segregation, surface crystal orientation, and morphology by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), reflection optical microscopy (ROM), and two-dimensional grazing incident wide-angle X-ray scattering (2D GIWAXS) methods. ATR-FTIR results indicated that the surface fraction of PLLA block increased from 0.48 to 0.79 when T(c,PLLA) increased from 70 to 110 °C. Polarized ATR-FTIR and 2D GIWAXS results indicated that PLLA crystal lamellae preferentially oriented parallel to the film surface with increasing T(c,PLLA). The surface crystallinity of PLLA was almost independent of T(c,PLLA), while the surface crystallinity of PEG decreased with increasing T(c,PLLA). On the basis of surface crystal orientation and crystallization kinetics, we suggested that the excess of PLLA component at the surface was mainly dominated by a coupling effect of crystallization behavior and surface segregation.

The Pax3 gene has been proven to play a crucial role in determining myogenic progenitor cell fate during embryonic myogenesis; however, the molecular role of Pax3 in myoblast development during later stages of myogenesis is unknown. We hypothesized that Pax3 would function in myoblast proliferation and differentiation; therefore, we employed three short hairpin RNAs (shRNAs) (shRNA1, shRNA2, and shRNA3) that target Pax3 to characterize the function of Pax3 in duck myoblast development. The mRNA and protein expression levels of Pax3 in duck myoblasts were detected using real-time PCR and Western blotting. Cell proliferation was assessed using the MTT and BrdU assays, while cell differentiation was assayed using immunofluorescence labeling with a MyoG antibody. Additionally, folic acid (FA), which is a rescue tool, was added into the medium of duck myoblasts to indirectly examine the function of Pax3 on duck myoblast proliferation and differentiation. The results revealed that one of the shRNA vectors, shRNA1, could significantly and stably reduce the expression of Pax3 (P < 0.05). Silencing Pax3 by shRNA1 significantly reduced the proliferation and differentiation of duck myoblasts (P < 0.05) due to downregulated expression of myogenic regulator factors. These trends could be rescued by adding FA; and Pax7, a paralog gene of Pax3, was involved in those processes. Overall, Pax3 had a positive function in duck myoblast proliferation and differentiation by modulating the expression of myogenic regulation factors, and shRNA targeting of Pax3 might be a new approach for understanding the function of Pax3 in the development of diverse tissues.