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Polyetheretherketone (PEEK), with good biocompatibility and similar mechanical properties to natural bone, is extensively employed in the manufacture of prostheses. However, the precision and mechanical properties of current implants are major challenges for clinical applications. In this study, the effect of pore size, raster angle and printing temperature were investigated on length, width, thickness, material consumption, compressive strength and Young's modulus. Taguchi design of experiment method was used to reduce the number of experiments and optimize the printing process parameters. Finally, predictive analysis was exploited to give the optimal set of process parameters. Experimental results indicated that the approach applied in this work provided more accurate predictions and control of the response variables. The maximum compressive strength and compressive modulus of PEEK scaffolds reached 43.4 MPa and 253.3 MPa, respectively. Therefore, the methodology of present work has the potential to meet the demand of design precision and manufacture of customized bone substitutes. [ABSTRACT FROM AUTHOR]

The present study was aimed at evaluating the histochemical distribution of alkaline phosphatase (ALP), nonspecific esterase (NSE), peroxidase (POD) and various types of mucous cells in the gill, mantle and hepatopancreas of the ark shell Scapharca subcrenata. The ALP activity was found in the epithelial cells (EP) of the gill filament and the mantle as well as in the basal lamina of the glandular duct in the hepatopancreas. The staining intensity of ALP in the mantle and hepatopancreas was stronger than that in the gill. The NSE activity was detected in the EP in the gill filament, mantle and hepatopancreas, with the hepatopancreas showing a stronger intensity than the gill. The POD activity was located in the EP of the mantle and glandular duct of the hepatopancreas as well as in the connective tissue of the gill. The mantle showed stronger staining intensity of POD than the hepatopancreas. The Alcian blue (pH 2.5) periodic acid Schiff (AB-PAS) histochemical results revealed four types of mucous cells in the gill, mantle and hepatopancreas. Type III cells (nPAS+AB+) and type IV cells (aPAS+AB+) were observed in the gill, mantle and hepatopancreas. Type I cells (PAS+AB-) were not detected in the hepatopancreas but were distributed ubiquitously throughout the gill filament and mantle. Type II cells (PAS--AB+) were not detected in the gill but were distributed ubiquitously in the digestive ducts of the hepatopancreas. KEY WORDS: enzyme activity, mucous cells, histochemical techniques, ark shell, Scapharca subcrenata, INTRODUCTION The bivalve mollusc has various enzymes and mucous cells distributing widely in the host tissues. They play an important role in the growth, development and immune defense of the [...]

Breast cancer is the most frequent malignant disease in women worldwide. It is a heterogeneous and complex genetic disease with different molecular characteristics. MAPT-AS1, a long non-coding RNA (lncRNA) existing at the anti-sense strand of the MAPT (microtubule associated protein tau) promoter region, was believed to regulate MAPT, which was associated with disease state in Parkinson's disease. But the role of MAPT-AS1 in breast cancer has never been reported. In our study we found that MAPT-AS1 is overexpressed in breast cancer but not in triple negative breast cancer (TNBC), and that high expression of MAPT-AS1 was correlated with better patient survival. In addition, the level of MAPT-AS1 was correlated with the expression of MAPT, and MAPT was associated with survival time in breast cancer. Our study suggests that MAPT-AS1 may play a role and be a potential survival predictive biomarker in breast cancer. Key words: breast cancer, MAPT-AS1, long non-coding RNA, patient survival. Le cancer du sein est l'affection maligne la plus frequente chez la femme a travers le monde. Il s'agit d'une maladie genetique heterogene et complexe qui presente differentes caracteristiques moleculaires. MAPT-AS1, un long ARN non codant (ARNnm) qui agit comme brin anti-sens dans la region du promoteur de la proteine associee aux microtubules MAPT (<< microtubule associated protein tau >>), est presume reguler MAPT qui a ete associee a la maladie de Parkinson. Toutefois, le role de MAPT-AS1 dans le cancer du sein n'a jamais ete rapporte. Les auteurs ont trouve dans cette etude que MAPT-AS1 est surexprime dans le cancer du sein, mais pas dans le cancer du sein triple negatif, et qu'une expression elevee de MAPT-AS1 etait correlee a une meilleure survie chez les patientes. De plus, le niveau de MAPT-AS1 etait correle avec celui de MAPT, associee a la duree de vie dans lecancer dusein. Leur etude suggere que MAPT-AS1 peut jouerun role dansle cancer du seinet agir commeunpotentiel biomarqueur predictif de la survie. [Traduit par la Redaction] Mots-cles : cancer du sein, MAPT-AS1, long ARN non codant, survie des patientes., Introduction Breast cancer is the most malignant cancer in females and it is estimated that approximately 252 710 new cases of invasive breast cancer are expected to be diagnosed in [...]

An acute infectious disease of northern sheatfish (Silurus soldatovi) was found in a commercial aquaculture pond in Tianjin, China. Herein, two dominant bacterial strains were isolated from naturally diseased northern sheatfish and identified as Aeromonas veronii and Vibrio cholerae. Seven healthy and seven naturally diseased fish that were collected from the pond were used for the gut microbiota analysis by high‐throughput 16S rRNA gene sequencing. The α‐diversity indices (ACE, Chao 1, and Shannon) did not differ significantly between diseased and healthy fish (p > 0.05), but a significant separation was observed between them when β‐diversity analysis of the bacterial population was performed. The diseased fish demonstrated a significant elevation in the relative abundances of Aeromonas, Vibrio, Blautia, and Megamonas and a decrease in Cetobacterium, Bacteroides, Chryseolinea, Ralstonia, and Pseudomonas compared with healthy fish (p < 0.05). Linear discriminant analysis effect size showed that microbial marker species in the diseased fish were in the order Aeromonadales, the family Aeromonadaceae, and the genus Aeromonas. The functional profiles of the microbial community that were predicted using the PICRUSt2 indicated that the disturbance of gut microbiota caused the alteration of its functional profiles in the diseased fish. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA), a biodegradable polymer, has become a major raw material in the field of 3D printing. However, some defects such as high brittleness and average bioactivity limit its application. In this study, a novel 3D printing composite of animal bone powder/polyethylene glycol/polylactic acid was prepared and investigated. The structures and properties of bHA/PEG/PLA composites were compared with commercial micron‐sized hydroxyapatite (mHA) and nano hydroxyapatite (nHA) composites. The study results show that the bHA has the same chemical structure as mHA and nHA, but its average particle size is 390 nm, which is quite different from mHA and nHA. When the PEG content is 14%, the toughness of the PEG/PLA blends is good, and its elongation at break reaches 96.23%. The bending strength, tensile strength, and elongation at break of bHA/PEG/PLA composites reach 25.1 MPa, 16.3 MPa, and 11.32%, respectively, which are all higher than those of mHA/PEG/PLA and similar to those of nHA/PEG/PLA. The bHA/PEG/PLA biological scaffolds prepared by 3D printing show good biocompatibility in cytotoxicity experiments and have good application prospects in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Hemocyte types of the Macrobrachium prawn Macrobrachium rosenbergii were identified using the methods of flow cytometry and light microscopy. The activities of endoenzymes including peroxidase (POD), phenoloxidase (PO), and alkaline phosphatase (ALP) in hemocytes were analyzed by cytochemical and biochemical methods. Mitochondrial membrane potential (MMP) of the hemocyte was probed according to the accumulation of the cyanine dye, 3',3'-dihexyloxacarbocyanine iodide, in the mitochondrial matrix. The results showed that there were three types of circulating hemocytes (hyalinocytes, semigranulocytes, and granulocytes) in M. rosenbergii. Enzymes POD, PO, and ALP were more abundant and active in granulocytes and semigranulocytes than in hyalinocytes. The data associated with MMP showed that the fluorescence intensity in the hemocyte was directly correlated to ceil complexity. The MMP in granulocytes was significantly greater than that in semigranulocytes, and the latter was significantly greater than that in hyalinocytes. KEY WORDS: endoenzymes, mitochondrial membrane potential, hemocyte types, Macrobrachium rosenbergii, INTRODUCTION Freshwater prawns Macrobrachium rosenbergii, having high commercial value and suitability for use in a variety of culture systems, are an important culture fishery species in China and in other [...]

In the Redclaw Crayfish, Cherax quadricarinatus, males grow larger and faster than females, and interest has focused on monosex breeding techniques for the production of males only. The adult male and female sexual characteristics of Cherax quadricarinatus are easily distinguished but cannot be determined in the embryo and juvenile stages. Because there is no DNA marker for the identification of sex in Cherax quadricarinatus, we sequenced its juvenile transcriptome in order to produce a reliable transcript to determine sex and to investigate its sex differentiation mechanisms at the molecular level. In this study, a female sex‐linked expression gene CqLRPPRC (Leucine‐rich PPR‐motif‐containing) of Cherax quadricarinatus was found in the transcriptome. Using semi‐quantitative RT‐PCR analysis, we found that the expression of the LRPPRC (leucine‐rich pentatricopeptide repeat cassette) gene was greater in the ovaries of females than in the testes of males, from the early juvenile stages onwards. Furthermore, in situ hybridization showed that the expression of its sexual dimorphism may be focused in the gonads. The results of an RNA interference treatment showed that a knockdown of CqLRPPRC up‐regulated the expression of vitellogenin (Vtg). The LRPPRC gene, and characteristic of shrimp, are reported here for the first time, and an assay of this gene can provide a molecular test to determine the sex of Cherax quadricarinatus in its different developmental stages, especially those during which no obvious sexual differences are visible. [ABSTRACT FROM AUTHOR]

ABSTRACT To investigate the in vitro generation of nitric oxide (NO) and superoxide anion ([O.sub.2.sup.-]) by Crassostrea ariakensis hemocytes stimulated with rickettsialike organisms (RLOs), RLOs were purified from infected C. [...]

ABSTRACT Light and electron microscopical studies were carried out to characterize the hemocytes of the oyster, Crassostrea ariakensis. Three types of hemocytes were recognized: granulocytes, large hyalinocytes and small hyalinocytes. [...]

In this study, the delimitation of intestine segments of koi carp (Cyprinus carpio var. koi) was conducted using a histological approach with the measurements of height of mucosa folds (HF), width of mucosa folds (WF), thickness of muscularis (TM) and cross‐sectional area (CSA). According to the change trends for these four parameters, the intestine of the koi carp was divided into anterior intestine, middle intestine and posterior intestine. The locations of the three intestine segments were defined, and their ratios along the entire intestine were accounted for 23.84 ± 1.18%, 46.77 ± 2.29% and 29.39 ± 1.65%, respectively. The anterior intestine had a significantly higher HF, compared with the middle (p <.01) or posterior intestines (p <.01). The muscularis became thin gradually from the anterior intestine to posterior part. TM was significantly different among the anterior, middle and posterior intestines (p <.01). The anterior intestine had a significantly higher CSA, compared with the middle (p <.01) and posterior intestines (p <.01), and the latter two segments had similar CSA values (p >.05). The procedure of the delimitation of the koi carp intestine segments can offer useful information for future studies on other fish species. The presented results are meaningful for studies on differential functions of the different intestine segments in fish. [ABSTRACT FROM AUTHOR]

Abstract Background DNA methylation plays important biological roles in plants and animals. To examine the rice genomic methylation landscape and assess its functional significance, we generated single-base resolution DNA methylome maps for Asian cultivated rice Oryza sativa ssp. japonica, indica and their wild relatives, Oryza rufipogon and Oryza nivara. Results The overall methylation level of rice genomes is four times higher than that of Arabidopsis. Consistent with the results reported for Arabidopsis, methylation in promoters represses gene expression while gene-body methylation generally appears to be positively associated with gene expression. Interestingly, we discovered that methylation in gene transcriptional termination regions (TTRs) can significantly repress gene expression, and the effect is even stronger than that of promoter methylation. Through integrated analysis of genomic, DNA methylomic and transcriptomic differences between cultivated and wild rice, we found that primary DNA sequence divergence is the major determinant of methylational differences at the whole genome level, but DNA methylational difference alone can only account for limited gene expression variation between the cultivated and wild rice. Furthermore, we identified a number of genes with significant difference in methylation level between the wild and cultivated rice. Conclusions The single-base resolution methylomes of rice obtained in this study have not only broadened our understanding of the mechanism and function of DNA methylation in plant genomes, but also provided valuable data for future studies of rice epigenetics and the epigenetic differentiation between wild and cultivated rice.

Crucian carp (Carassius auratus) is one of the major freshwater species and important food fish in China. Fish skin acts as the first line of defence against pathogens, yet its molecular and immune mechanism remains unclear. In this study, a de novo transcriptome assembly of C. auratus skin was performed with the Illumina Hiseq 2000 platform. A total of 49,154,776 clean reads were assembled, among which 60,824 (46.86%), 37,103 (28.59%), 43,269 (33.33%) unigenes were annotated against National Center for Biotechnology Information, Gene Onotology and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, respectively. KEGG Orthology categories were significantly involved in immune system (20.50%), signal transduction (18.04%) and mucosal mucin genes (e.g., muc2, muc5AC, muc5B, muc17, muc18). The high expression of muc18 gene was observed in brain; that of muc2 in intestine; and that of muc5AC in skin, liver, spleen, intestine and muscle. Moreover, the potential 28,928 simple sequence repeats with the three most abundant dinucleotide repeat motifs (AC/GT, AG/CT, AT/AT) were detected in C. auratus. To authors' knowledge, this is the first report to describe the transcriptome analysis of C. auratus skin, and the outcome of this study contributed to the understanding of mucosal immune response of the skin and molecular markers in cyprinid species. [ABSTRACT FROM AUTHOR]

Fish intestine is an important constituent of the mucosal immune system. The gut and gut-associated lymphoid tissue construct a local immune environment. A Shewanella algae strain was previously reported to be a pathogen causing ascitic disease accompanied with intestinal inflammation in Cynoglossus semilaevis. This study aimed to investigate the intestine immune response in C. semilaevis to S. alga e infection at the protein level. Two-dimensional electrophoresis coupled with mass spectrometry proteomics was utilized to compare protein expression in the intestines from normal and S. algae -infected C. semilaevis. A total of 70 differentially expressed proteins (DEPs), consisting of 16 upregulated and 54 downregulated proteins, were identified in the intestine tissue of C. Semilaevis. These protein expression changes were further validated using western blot analysis and quantitative real-time PCR. Gene ontology enrichment analysis showed that these 70 DEPs could be assigned across three categories: "cellular components", "molecular function", and "biological process". Forty-one DEPs (six up-regulated and 35 down-regulated proteins) related to metabolic processes were identified. In addition, 20 DEPs (eight up-regulated and 12 down-regulated proteins) related to stress and immune responses were identified. A protein-protein interaction network generated by the STRING (Search Tool for the Retrieval of Interacting Genes/protein) revealed that 30 DEPs interacted with one another to form an integrated network. Among them, 29 DEPs were related to stress, immune, and metabolism processes. In the network, some of the immune related proteins (C9, FGB, KNG1, apolipoprotein A-IV-like, and PDIA3) were up-regulated and most DEPs involved in metabolism processes were down-regulated. These results indicate that the immune defense response of the intestine was activated and the intestinal function associated with metabolism processes was disturbed. This study provides valuable information for further research into the functions of these DEPs in fish. • The protein expression was compared in intestine of normal and S. algae -infected C. semilaevis. • Seventy differentially expressed proteins (DEPs) were identified. • Protein-protein interaction analysis indicated that 29 DEPs were interrelated. • The immune defense was activated and metabolic processes were disturbed in intestine. [ABSTRACT FROM AUTHOR]

Rahnella aquatilis is an important pathogen of several aquatic organisms and is found widely distributed in the freshwater, soil, fish and human clinical samples. Our previously published study reported a novel pathogenic R. aquatilis strain KCL‐5 to crucian carp (Carassius auratus). To further investigate the characteristics and pathogenesis caused by R. aquatilis, we here report on the pathological changes, bacterial genomic and proteomic analyses of strain KCL‐5. Significantly pathological changes in liver, intestine, spleen and gills were observed in infected fish. The genome consists of one circular chromosome 5,062,299 bp with 52.02% GC content and two plasmids (506,827 bp, 52.16%; 173,433 bp, 50.00%) and predicted 5,653 genes, 77 tRNAs and 22 rRNAs. Some virulence factors were characterized, including outer membrane protein, haemolysin, RTX toxin, chemotaxis and T3SS secretion system. Antimicrobial resistance genes such as EmrAB‐TolC, MexABC‐OpmB and RosAB efflux pump were found in strain KCL‐5. KEGG analysis showed that mainly functional modules were ABC transporters, biosynthesis of amino acids, two‐component system, quorum sensing, flagellum assembly and chemotaxis, in which most of them were identified by using 2‐DE/MS analyses. To our knowledge, this was first report on the molecular characteristics of R. aquatilis by multi‐omics approaches, which will provide insights into the pathogenic mechanism of R. aquatilis infection in fish. [ABSTRACT FROM AUTHOR]