Genomic Selection Using BayesCπ and GBLUP for Resistance Against <Emphasis Type="Italic">Edwardsiella tarda</Emphasis> in Japanese Flounder (<Emphasis Type="Italic">Paralichthys olivaceus</Emphasis>)

The Japanese flounder is one of the most widely farmed economic flatfish species throughout eastern Asia including China, Korea, and Japan. Edwardsiella tarda is a major species of pathogenic bacteria that causes ascites disease and, consequently, a huge economy loss for Japanese flounder farming. After generation selection, traditional breeding methods can hardly improve the E. tarda resistance effectively. Genomic selection is an effective way to predict the breeding potential of parents and has rarely been used in aquatic breeding. In this study, we chose 931 individuals from 90 families, challenged by E. tarda from 2013 to 2015 as a reference population and 71 parents of these families as selection candidates. 1,934,475 markers were detected via genome sequencing and applied in this study. Two different methods, BayesCπ and GBLUP, were used for genomic prediction. In the reference population, two methods led to the same accuracy (0.946) and Pearson’s correlation results between phenotype and genomic estimated breeding value (GEBV) of BayesCπ and GBLUP were 0.912 and 0.761, respectively. In selection candidates, GEBVs from two methods were highly similar (0.980). A comparison of GEBV with the survival rate of families that were structured by selection candidates showed correlations of 0.662 and 0.665, respectively. This study established a genomic selection method for the Japanese flounder and for the first time applied this to E. tarda resistance breeding.     

An Excitatory Neural Assembly Encodes Short-Term Memory in the Prefrontal Cortex

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The superior fault tolerance of artificial neural network training with a fault/noise injectionbased genetic algorithm

Artificial neural networks (ANNs) are powerful computational tools that are designed to replicate the human brain and adopted to solve a variety of problems in many different fields. Fault tolerance (FT), an important property of ANNs, ensures their reliability when significant portions of a network are lost. In this paper, a fault/noise injection-based (FIB) genetic algorithm (GA) is proposed to construct fault-tolerant ANNs. The FT performance of an FIB-GA was compared with that of a common genetic algorithm, the back-propagation algorithm, and the modification of weights algorithm. The FIB-GA showed a slower fitting speed when solving the exclusive OR (XOR) problem and the overlapping classification problem, but it significantly reduced the errors in cases of single or multiple faults in ANN weights or nodes. Further analysis revealed that the fit weights showed no correlation with the fitting errors in the ANNs constructed with the FIB-GA, suggesting a relatively even distribution of the various fitting parameters. In contrast, the output weights in the training of ANNs implemented with the use the other three algorithms demonstrated a positive correlation with the errors. Our findings therefore indicate that a combination of the fault/noise injection-based method and a GA is capable of introducing FT to ANNs and imply that the distributed ANNs demonstrate superior FT performance.     

Locus Mapping,Molecular Cloning,and Expression Analysis of <Emphasis Type="Italic">rps6kb2</Emphasis>, a Novel Metamorphosis-Related Gene in Chinese Tongue Sole (<Emphasis Type="Italic">Cynoglossus semilaevis</Emphasis>)

Flatfish metamorphosis denotes the extraordinary transformation of a symmetric pelagic larva into an asymmetric benthic juvenile. This unique process involves eye migration, a 90° rotation in posture, and asymmetrical pigmentation for adaptation to a benthic lifestyle. In the present study, we used genetics to map a metamorphosis-related locus (q-10M) in the male linkage group (LG10M), a small interval of 0.9 cM corresponding to a 1.8 M-bp physical area in chromosome 9 in the Chinese tongue sole (Cynoglossus semilaevis). Combined with single-marker analysis, ribosomal protein S6 kinase 2 (rps6kb2) a member of the family of AGC kinases was identified as a novel metamorphosis-related candidate gene. Its expression pattern during metamorphosis was determined by quantitative RT-PCR and whole-mount in situ hybridization analysis. rps6kb2 gene was significantly expressed in metamorphic climax stage larvae and distributed in all the tissues transforming during metamorphosis, including tail, jaw, eye and skin of larvae. The results suggest that rps6kb2 has a general role in tissue transformations during flatfish metamorphosis including tail changes, skull remodeling, eye migration, and asymmetrical pigmentation.     

Determination of Benzalkonium Chloride Partition in Micelle Solutions Using Ultrafiltration Method

The objectives of this study were to determine the concentrations of free benzalkonium chloride (BAC) and apparent partitions coefficients (K _m) in micelle solutions and to explore its application in formulation development. Ultrafiltration (UF) was carried out using 10K Nanosep® devices and centrifugation at 5,000 rpm for 5 min. The separation of free BAC from micellar solutions was also conducted using ultracentrifugation (UC) method for the comparison with UF method. Capillary electrophoresis method was used for the identification of micelles. Results showed that a UF method was applicable for quantitatively evaluating BAC–micelle interaction in micellar solutions. Unlike UF, UC could not completely separate free BAC from the micelles. The free BAC concentrations in the micelle solutions decreased with increasing surfactant concentrations. Among polysorbate 80, cremophor EL, and tyloxapol, BAC had the highest K _m in polysorbate 80 solutions. The K _m was significantly lower in non-buffered aqueous solutions than that in citric buffers. Moreover, increasing surfactant concentrations led to reducing antimicrobial activity. The UF is a rapid and accurate method that minimally alters the micellar equilibrium for the determination of free BAC and K _m in micellar solutions. In conclusion, free BAC concentration, which is a function of surfactant type, surfactant concentration, and ion strength of solution, is likely associated with the antimicrobial activity.     

Bifidobacteria alleviate experimentally induced colitis by upregulating indoleamine 2, 3‐dioxygenase expression

The goal of this study was explore the role of indoleamine 2, 3‐dioxygenase (IDO) in the therapeutic effect of probiotics on inflammatory bowel disease (IBD). Trinitrobenzene sulfonic acid (TNBS) was used to induce colitis in mice and 1‐methyltryptophan (1‐MT) to block expression of IDO. Clinical manifestations and macroscopic and microscopic colonic changes were assessed using a disease activity index (DAI), the Wallace–Keenan, and Curtner scoring systems, respectively. Expression of colonic IDO was detected by western blot. Immunohistochemistry analysis to evaluate numbers of CD11c⁺ cells and expression of IL‐17 and Foxp3 showed that DAI, Wallace–Keenan, and Curtner scores were lower in the Bifidobacteria treatment group than the control group and that the therapeutic effect of Bifidobacteria was blocked by 1‐MT (P < 0.05). Additionally, Bifidobacteria were found to increase expression of IDO and the numbers of CD11c⁺ cells, CD11c⁺ and IDO double positive cells and Foxp3⁺ Treg cells, while decreasing the number of IL‐17⁺cells (P < 0.05). The generation of Foxp3⁺ Treg cells induced by Bifidobacteria was abrogated by 1‐MT (P < 0.05). These findings study suggest that Bifidobacteria attenuate TNBS‐induced colitis by inducing expression of IDO, which further increases generation of Foxp3⁺ Treg cells.

     

Construction of a High-Density Microsatellite Genetic Linkage Map and Mapping of Sexual and Growth-Related Traits in Half-Smooth Tongue Sole (Cynoglossus semilaevis)

High-density genetic linkage maps of half-smooth tongue sole were developed with 1007 microsatellite markers, two SCAR markers and an F1 family containing 94. The female map was composed of 828 markers in 21 linkage groups, covering a total of 1447.3 cM, with an average interval 1.83 cM between markers. The male map consisted of 794 markers in 21 linkage groups, spanning 1497.5 cM, with an average interval of 1.96 cM. The female and male maps had 812 and 785 unique positions, respectively. The genome length of half-smooth tongue sole was estimated to be 1527.7 cM for the females and 1582.1 cM for the males. Based on estimations of the map lengths, the female and male maps covered 94.74 and 94.65% of the genome, respectively. The consensus map was composed of 1007 microsatellite markers and two SCAR markers in 21 linkage groups, covering a total of 1624 cM with an average interval of 1.67 cM. Furthermore, 159 sex-linked SSR markers were identified. Five sex-linked microsatellite markers were confirmed in their association with sex in a large number of individuals selected from different families. These sex-linked markers were mapped on the female map LG1f with zero recombination. Two QTLs that were identified for body weight, designated as We-1 and We-2, accounted for 26.39% and 10.60% of the phenotypic variation. Two QTLs for body width, designated Wi-1 and Wi-2, were mapped in LG4f and accounted for 14.33% and 12.83% of the phenotypic variation, respectively. Seven sex-related loci were mapped in LG1f, LG14f and LG1m by CIM, accounting for 12.5–25.2% of the trait variation. The results should prove to be very useful for improving growth traits using molecular MAS.     

Restoration of FMRP expression in adult V1 neurons rescues visual deficits in a mouse model of fragile X syndrome

Many people affected by fragile X syndrome(FXS)and autism spectrum disorders have sensory processing deficits,such as hypersensitivity to auditory,tactile,and v...     

Lipid metabolites and their differential pro-arrhythmic profiles: of importance in the development of a new anti-arrhythmic pharmacology

Arrhythmias have been treated for a long time with drugs that mainly target the ionic pumps and channels. These anti-arrhythmic regimens per se introduce new arrhythmias, which can be detrimental to patients. Advances in development of novel pharmacology without introduction of iatrogenic arrhythmias are thus favorable for an effective treatment of arrhythmias. Electrophysiological stability of the heart has been shown to be closely associated with cardiac metabolism. The present effective anti-arrhythmic drugs such as beta-blockers and amiodarone have profound beneficial effects in regulating myocardial metabolism. Aiming at decreasing production of toxic metabolites or preventing accumulation of arrhythmogenic lipids perhaps is a good strategy to effectively control arrhythmias. Therefore, a better understanding of the pro-arrhythmic profiles of cardiac metabolites helps to explore a new generation of metabolically oriented anti-arrhythmic medications. In this review, we present several lipid metabolites and summarize their arrhythmogenic characteristics.