Change of eye shape during metamorphosis in two flatfishes, Paralichthys olivaceus and Solea senegalensis, with comparison of eye shape within the Pleuronectiformes

The most remarkable developmental event during metamorphosis in flatfish (Pleuronectiformes) is the migration of their eyes; one eye migrates upwards, then passes through the dorsal midline, and finally stops on the other side. In this study, we determined that the ratio of the movable eye diameter on the transverse axis (DTA) to that on the vertical axis (DVA) increased during the metamorphosis of Paralichthys olivaceus and Solea senegalensis. Based on the recently proposed hypothesis that eye migration of flatfishes is caused by the push force from the proliferated tissue of the suborbital region, we postulated that the eye shape change is a result of the same force. Measurements of eye proportions in 20 species of adult flatfishes revealed that the DTA is constantly larger than the DVA, suggesting that the mechanisms of eye shape change and eye migration driven by proliferating cells in the suborbital tissue are universal among flatfishes.     

Adiponectin: A biomarker for rheumatoid arthritis?

Recent achievements in the biology and the function of adipose tissue have regarded white adipose tissue (WAT) as an important endocrine and secretory organ. Releasing a series of multiple-function mediators, WAT is involved in a wide spectrum of diseases, including not only cardiovascular and metabolic complications, such as atherosclerosis and type 2 diabetes, but also inflammatory- and immune-related disorders, such as rheumatoid arthritis (RA) and osteoarthritis (OA). A large number of these mediators, called adipokines, such as tumor necrosis factor alpha (TNF-α), leptin, adiponectin, resistin, chemerin, interleukin-6 (IL-6), visfatin, and so on have been identified and studied widely. Important advances related to these proteins shed new insights into the pathophysiological mechanisms of many complicated diseases, although details of which remain unclear. Adiponectin, one of the most widely investigated adipokine, has been shown to possess both anti- and pro-inflammatory effects. RA is a chronic systemic inflammatory-related autoimmune disease. Accumulated evidence has demonstrated that cytokines and adipokines play an important role in the pathogenesis of RA. In this review, we have summarized the most recent advances in adiponectin research in the context of RA, focusing primarily on its effect on RA-related cells, its regulation on pro-inflammatory cytokines, as well as its validation as a biomarker for RA.     

Cumulative Effect in Information Diffusion: Empirical Study on a Microblogging Network

Cumulative effect in social contagion underlies many studies on the spread of innovation, behavior, and influence. However, few large-scale empirical studies are conducted to validate the existence of cumulative effect in information diffusion on social networks. In this paper, using the population-scale dataset from the largest Chinese microblogging website, we conduct a comprehensive study on the cumulative effect in information diffusion. We base our study on the diffusion network of message, where nodes are the involved users and links characterize forwarding relationship among them. We find that multiple exposures to the same message indeed increase the possibility of forwarding it. However, additional exposures cannot further improve the chance of forwarding when the number of exposures crosses its peak at two. This finding questions the cumulative effect hypothesis in information diffusion. Furthermore, to clarify the forwarding preference among users, we investigate both structural motif in the diffusion network and temporal pattern in information diffusion process. Findings provide some insights for understanding the variation of message popularity and explain the characteristics of diffusion network.     

Tissue-Specific and Cation/Anion-Specific DNA Methylation Variations Occurred in C. virgata in Response to Salinity Stress

Salinity is a widespread environmental problem limiting productivity and growth of plants. Halophytes which can adapt and resist certain salt stress have various mechanisms to defend the higher salinity and alkalinity, and epigenetic mechanisms especially DNA methylation may play important roles in plant adaptability and plasticity. In this study, we aimed to investigate the different influences of various single salts (NaCl, Na₂SO₄, NaHCO₃, Na₂CO₃) and their mixed salts on halophyte Chloris. virgata from the DNA methylation prospective, and discover the underlying relationships between specific DNA methylation variations and specific cations/anions through the methylation-sensitive amplification polymorphism analysis. The results showed that the effects on DNA methylation variations of single salts were ranked as follows: Na₂CO₃> NaHCO₃> Na₂SO₄> NaCl, and their mixed salts exerted tissue-specific effects on C. virgata seedlings. Eight types of DNA methylation variations were detected and defined in C. virgata according to the specific cations/anions existed in stressful solutions; in addition, mix-specific and higher pH-specific bands were the main type in leaves and roots independently. These findings suggested that mixed salts were not the simple combination of single salts. Furthermore, not only single salts but also mixed salts showed tissue-specific and cations/anions-specific DNA methylation variations.     

Serum Levels of Fibroblast Growth Factor 19 Are Inversely Associated with Coronary Artery Disease in Chinese Individuals

Background

The fibroblast growth factor 19 (FGF19) has been implicated in recent studies as a potential regulator of glucose and lipid metabolism, which may lead to atherosclerosis. Here, we investigated the association of FGF19 with the presence and severity of coronary artery disease (CAD) in a Chinese population.

Methods

A total of 315 patients with suspected or established CAD, including 205 males and 110 postmenopausal females, were enrolled and assessed by coronary angiography. CAD severity was determined by the Gensini score. Serum FGF19 was measured by quantitative sandwich ELISA.

Results

FGF19 levels were not significantly different between male and female patients (median [interquartile range], 143.40 [87.96–250.80] vs. 141.60 [87.13–226.32] pg/mL, P = 0.773). CAD patients had lower levels of FGF19 than those without CAD (128.20 [80.62–226.58] vs. 188.00 [105.10–284.70] pg/mL, P = 0.007). FGF19 was negatively correlated with 2hPG (r = –0.150, P = 0.008), FINS (r = –0.169, P = 0.004), HOMA-IR (r = –0.171, P = 0.004), and the Gensini score (r = –0.141, P = 0.012), but positively correlated with HDL-c (r = 0.116, P = 0.041) and adiponectin (r = 0.128, P = 0.024). Moreover, FGF19 was found to be independently correlated with 2hPG (β = –0.146, P = 0.022) and adiponectin (β = 0.154, P = 0.016). After adjusting for other CAD risk factors, FGF19 was demonstrated to be an independent factor for Gensini score (β = –0.140, P = 0.019) and the presence of CAD (β = –1.248, P = 0.036).

Conclusions

Serum FGF19 is associated with the presence and severity of CAD in a Chinese population.     

Molecular Phylogeny of the Butterfly Genus Polytremis (Hesperiidae,Hesperiinae, Baorini) in China

Background

The genus Polytremis, restricted to the continental part of the southeastern Palaearctic and northern Oriental regions, is one of the largest and most diverse lineages of the tribe Baorini. Previous studies on the genus were focused mainly on morphological classification and identification of new species. Due to the lack of effective and homologous traits of morphology, there were many challenges in the traditional classification. In this report, we reconstruct the phylogeny to provide a solid framework for these studies and to test the traditional limits and relationships of taxa.

Methodology and Principal Findings

We sequenced a mitochondrial and three nuclear gene fragments, coupled with an evaluation of traditional morphological characters, to determine the phylogenetic relationships for a total of 15 species representing all major species groups of the Polytremis genus in China, and to elucidate their taxonomic status.

Conclusions and Significance

Analysis of mitochrondial and nuclear DNA showed considerable congruent phylogenetic signal in topology at the inter-species level. We found strong support for the monophyly of Polytremis and some clades were recognized with morphological data. Thus, the COI sequence in our study could be used as a DNA barcode to identify almost all members of the genus. However, incongruences of phylogenetic analyses occurred: in contrast to the phylogenetic trees of mitochondrial COI, it was not possible for nuclear rDNA to discriminate P. gotama from P. caerulescens, suggesting a possible recent separation of these two species. Additionally, P. theca was the only species with a greater intra-specific genetic distance compared to some inter-specific genetic distances in this study and some problems associated with the cryptic diversity of the species are discussed. The results of this study will helpful to reveal the causes of the high degree of diversity of butterflies, and possibly other groups of insects in China.     

Bayesian Network Analysis Reveals Alterations to Default Mode Network Connectivity in Individuals at Risk for Alzheimer's Disease

Alzheimer''s disease (AD) is associated with abnormal functioning of the default mode network (DMN). Functional connectivity (FC) changes to the DMN have been found in patients with amnestic mild cognitive impairment (aMCI), which is the prodromal stage of AD. However, whether or not aMCI also alters the effective connectivity (EC) of the DMN remains unknown. We employed a combined group independent component analysis (ICA) and Bayesian network (BN) learning approach to resting-state functional MRI (fMRI) data from 17 aMCI patients and 17 controls, in order to establish the EC pattern of DMN, and to evaluate changes occurring in aMCI. BN analysis demonstrated heterogeneous regional convergence degree across DMN regions, which were organized into two closely interacting subsystems. Compared to controls, the aMCI group showed altered directed connectivity weights between DMN regions in the fronto-parietal, temporo-frontal, and temporo-parietal pathways. The aMCI group also exhibited altered regional convergence degree in the right inferior parietal lobule. Moreover, we found EC changes in DMN regions in aMCI were correlated with regional FC levels, and the connectivity metrics were associated with patients'' cognitive performance. This study provides novel sights into our understanding of the functional architecture of the DMN and adds to a growing body of work demonstrating the importance of the DMN as a mechanism of aMCI.     

FLZ Alleviates the Memory Deficits in Transgenic Mouse Model of Alzheimer’s Disease via Decreasing Beta-Amyloid Production and Tau Hyperphosphorylation

Alzheimer’s disease (AD) is the most common cause of dementia worldwide and mainly characterized by the aggregated β-amyloid (Aβ) and hyperphosphorylated tau. FLZ is a novel synthetic derivative of natural squamosamide and has been proved to improve memory deficits in dementia animal models. In this study, we aimed to investigate the mechanisms of FLZ’s neuroprotective effect in APP/PS1 double transgenic mice and SH-SY5Y (APPwt/swe) cells. The results showed that treatment with FLZ significantly improved the memory deficits of APP/PS1 transgenic mice and decreased apoptosis of SH-SY5Y (APPwt/swe) cells. FLZ markedly attenuated Aβ accumulation and tau phosphorylation both in vivo and in vitro. Mechanistic study showed that FLZ interfered APP processing, i.e., FLZ decreased β-amyloid precursor protein (APP) phosphorylation, APP-carboxy-terminal fragment (APP-CTF) production and β-amyloid precursor protein cleaving enzyme 1 (BACE1) expression. These results indicated that FLZ reduced Aβ production through inhibiting amyloidogenic pathway. The mechanistic study about FLZ’s inhibitory effect on tau phosphorylation revealed t the involvement of Akt/glycogen synthase kinase 3β (GSK3β) pathway. FLZ treatment increased Akt activity and inhibited GSK3β activity both in vivo and in vitro. The inhibitory effect of FLZ on GSK3β activity and tau phosphorylation was suppressed by inhibiting Akt activity, indicating that Akt/GSK3β pathway might be the possible mechanism involved in the inhibitory effect of FLZ on tau hyperphosphorylation. These results suggested FLZ might be a potential anti-AD drug as it not only reduced Aβ production via inhibition amyloidogenic APP processing pathway, but also attenuated tau hyperphosphoylation mediated by Akt/GSK3β.     

RADtyping: An Integrated Package for Accurate De Novo Codominant and Dominant RAD Genotyping in Mapping Populations

Genetic linkage maps are indispensable tools in genetic, genomic and breeding studies. As one of genotyping-by-sequencing methods, RAD-Seq (restriction-site associated DNA sequencing) has gained particular popularity for construction of high-density linkage maps. Current RAD analytical tools are being predominantly used for typing codominant markers. However, no genotyping algorithm has been developed for dominant markers (resulting from recognition site disruption). Given their abundance in eukaryotic genomes, utilization of dominant markers would greatly diminish the extensive sequencing effort required for large-scale marker development. In this study, we established, for the first time, a novel statistical framework for de novo dominant genotyping in mapping populations. An integrated package called RADtyping was developed by incorporating both de novo codominant and dominant genotyping algorithms. We demonstrated the superb performance of RADtyping in achieving remarkably high genotyping accuracy based on simulated and real mapping datasets. The RADtyping package is freely available at http://www2.ouc.edu.cn/mollusk/ detailen.asp?id=727.