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Abiotic stress, including flooding, seriously affects the normal growth and development of plants. Mulberry (Morus alba), a species known for its flood resistance, is cultivated worldwide for economic purposes. The transcriptomic analysis has identified numerous differentially expressed genes (DEGs) involved in submergence tolerance in mulberry plants. However, a comprehensive analyses of metabolite types and changes under flooding stress in mulberry remain unreported. A non-targeted metabolomic analysis utilizing liquid chromatographytandem mass spectrometry (LC-MS/MS) was conducted to further investigate the effects of flooding stress on mulberry. A total of 1,169 metabolites were identified, with 331 differentially accumulated metabolites (DAMs) exhibiting up-regulation in response to flooding stress and 314 displaying down-regulation. Pathway enrichment analysis identified significant modifications in many metabolic pathways due to flooding stress, including amino acid biosynthesis and metabolism and flavonoid biosynthesis. DAMs and DEGs are significantly enriched in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways for amino acid, phenylpropanoid and flavonoid synthesis. Furthermore, metabolites such as methyl jasmonate, sucrose, and D-mannose 6-phosphate accumulated in mulberry leaves post-flooding stress. Therefore, genes and metabolites associated with these KEGG pathways are likely to exert a significant influence on mulberry flood tolerance. This study makes a substantial contribution to the comprehension of the underlying mechanisms implicated in the adaptation of mulberry plants to submergence. [ABSTRACT FROM AUTHOR]

Although it is generally accepted that eukaryotic gene order is not random, the basic principles of gene arrangement on a chromosome remain poorly understood. Here, we extended existing population genetics theories that were based on two-locus models and proposed a hypothesis that genetic interaction networks drive the evolution of eukaryotic gene order. We predicted that genes with positive epistasis would move toward each other in evolution, during which a negative correlation between epistasis and gene distance formed. We tested and confirmed our prediction with com-putational simulations and empirical data analyses. Importantly, we demonstrated that gene order in the budding yeast could be successfully predicted from the genetic interaction network. Taken together, our study reveals the role of the genetic interaction network in the evolution of gene order, extends our understanding of the encoding principles in genomes, and potentially offers new strategies to improve synthetic biology. [ABSTRACT FROM AUTHOR]

Codon usage bias (CUB) refers to the observation that synonymous codons are not used equally frequently in a genome. CUB is stronger in more highly expressed genes, a phenomenon commonly explained by stronger natural selection on translational accuracy and/or efficiency among these genes. Nevertheless, this phenomenon could also occur if CUB regulates gene expression at the mRNA level, a hypothesis that has not been tested until recently. Here, we attempt to quantify the impact of synonymous mutations on mRNA level in yeast using 3,556 synonymous variants of a heterologous gene encoding green fluorescent protein (GFP) and 523 synonymous variants of an endogenous gene TDH3. We found that mRNA level was positively correlated with CUB among these synonymous variants, demonstrating a direct role of CUB in regulating transcript concentration, likely via regulating mRNA degradation rate, as our additional experiments suggested. More importantly, we quantified the effects of individual synonymous mutations on mRNA level and found them dependent on 1) CUB and 2) mRNA secondary structure, both in proximal sequence contexts. Our study reveals the pleiotropic effects of synonymous codon usage and provides an additional explanation for the well-known correlation between CUB and gene expression level. [ABSTRACT FROM AUTHOR]

Background: There is limited information about the clinical and biological significance of prostate specific G protein coupled receptor (PSGR) in prostate cancer (PCa) initiation and progression. Here, we evaluated the expression of PSGR protein, studied its diagnostic and prognostic value in PCa, and also explored its role in cancer cell growth and invasion.Methods: The expression of PSGR in paired adjacent normal prostate, high grade prostatic intraepithelial neoplasia (PIN), and PCa were determined by immunohistochemistry on tissue microarrays constructed from 150 radical prostatectomy specimens. The effects of PSGR on PCa cell growth and invasion were investigated using human PCa cell lines.Results: Membranous and cytoplasmic PSGR staining was observed at luminal epithelial cells of prostate. PSGR protein expression was significantly higher in PIN compared to normal prostate. Interestingly, the expression of PSGR decreased as PIN progressed to PCa. Low PSGR expression in PCa was associated with high Gleason score, and poor overall survival. Activated PSGR increased cancer cell invasive ability, but retarded cell growth. PSGR did not affect mTOR activity, but suppressed P70 S6 kinase activity.Conclusions: PSGR may participate in PCa progression through affecting cell proliferation and invasion. High expression of PSGR in PIN may implicate its role in early neoplastic transformation of PCa. Low expression of PSGR in PCa may serve as a potential indicator for poor prognosis. [ABSTRACT FROM AUTHOR]

The article presents two case studies, one concerned with a female patient who presented with a one year case of abdominal pain and another concerned with a patient with multiple medical problems, including an incidental pedunculated polyp at his terminal ileum. A discussion of diagnostic testing which was conducted on both patients, and resulted in both of them receiving a diagnosis of small bowel polyploid lesions with the histological features of neuromuscular and vascular hamartoma, is presented.

Sprague-Dawley (SD) rats' normal and abnormal pancreatic tissues are determined directly by attenuated total reflectance Fourier transform infrared (ATR-FT-IR) spectroscopy method. In order to diagnose earlier stage of SD rats pancreatic cancer rate with FT-IR, a novel method of extraction of FT-IR feature using discrete wavelet transformation (DWT) analysis and classification with the probability neural network (PNN) was developed. The differences between normal pancreatic and abnormal samples were identified by PNN based on the indices of 4 feature variants. When error goal was 0.01, the total correct rates of pancreatic early carcinoma and advanced carcinoma were 98% and 100%, respectively. It was practical to apply PNN on the basis of ATR-FT-IR to identify abnormal tissues. The research result shows the feasibility of establishing the models with FT-IR-DWT-PNN method to identify normal pancreatic tissues, early carcinoma tissues, and advanced carcinoma tissues. [ABSTRACT FROM AUTHOR]

Surface water samples were collected from 19 sites in the northern Beibu Gulf in April 2011. Species composition and abundance of planktonic ciliates were investigated. They were combined with environmental data to obtain the spatial pattern of the ciliate community and its relationship with the environment. A total of 36 species belonging to 13 genera and 3 orders (Oligotrichida, Haptorida and Tintinnida) were identified, including 10 dominant species. All 19 samples were divided into three groups using cluster analysis and multidimensional scaling (MDS) on the basis of the ciliate species composition and abundance. Group 1 was the least abundant. The species of the order Oligotrichida dominated in Group 2. In contrast, Mesodinium species were of increased importance in Group 3. Redundancy analysis (RDA) revealed that ciliate communities were more closely related to the level of nitrogen (total nitrogen, nitrate nitrogen, nitrite nitrogen) and phosphorus (total phosphorus, active phosphorus) rather than other variables. As the levels of nitrogen and phosphorus increased, communities dominated by species from the order Oligotrichida were replaced by those dominated by Mesodinium species. [ABSTRACT FROM AUTHOR]

Objectives: To investigate metastasis associated in colon cancer 1 (MACC1) and MET expression in colorectal adenoma, Tis, early-stage invasive (T1 and T2), and advanced adenocarcinoma with liver metastasis using immunohistochemistry. Methods: Ninety-three paraffin-embedded colorectal tumor specimens were immunohistochemically analyzed for MACC1 and MET protein expression. Results: MACC1 expression was upregulated in the transition from adenoma to Tis; its expression was further elevated during tumor progression from Tis to early invasive carcinoma. MET expression was constant from adenoma to Tis and to T1 but significantly increased as tumor progression to T2. Both MACC1 and MET expression were enhanced in advanced carcinoma with liver metastasis. Conclusions: Stepwise elevation of MACC1 expression in key points of colorectal cancer development suggests that MACC1 may contribute to cancer initiation and early invasive growth. High expression of both MACC1 and MET may relate to distant metastasis. [ABSTRACT FROM AUTHOR]

Although evidence has shown the regulating effect of n-3 poly-unsaturated fatty acid (n-3 PUFA) on cell signaling transduction, it remains unknown whether n-3 PUFA treatment modulates estrogen signaling. The current study showed that docosahexaenoic acid (DHA, C22:6), eicosapentaenoic acid (EPA, C20:5) shifted the pro-survival and proliferative effect of estrogen to a pro-apoptotic effect in human breast cancer (BCa) MCF-7 and T47D cells. 17 β-estradiol (E2) enhanced the inhibitory effect of n-3 PUFAs on BCa cell growth. The IC50 of DHA or EPA in MCF-7 cells decreased when combined with E2 (10 nM) treatment (from 173 μM for DHA only to 113 μM for DHA+E2, and from 187 mm for EPA only to 130 mm for EPA+E2). E2 also augmented apoptosis in n-3 PUFA-treated BCa cells. In contrast, in cells treated with stearic acid (SA, C18:0) as well as cells not treated with fatty acid, E2 promoted breast cancer cell growth. Classical (nuclear) estrogen receptors may not be involved in the pro-apoptotic effects of E2 on the n-3 PUFA-treated BCa cells because ERa agonist failed to elicit, and ERa knockdown failed to block E2 pro-apoptotic effects. Subsequent studies reveal that G protein coupled estrogen receptor 1 (GPER1) may mediate the pro-apoptotic effect of estrogen. N-3 PUFA treatment initiated the pro-apoptotic signaling of estrogen by increasing GPER1-cAMP-PKA signaling response, and blunting EGFR, Erk 1/2, and AKT activity. These findings may not only provide the evidence to link n-3 PUFAs biologic effects and the pro-apoptotic signaling of estrogen in breast cancer cells, but also shed new insight into the potential application of n-3 PUFAs in BCa treatment. [ABSTRACT FROM AUTHOR]

Nano-sized SrTiO3-based oxygen sensors were fabricated from synthesized SrTiO3 and commercial SrTiO3 using the high-energy ball milling and the thick-film screen-printing techniques. The particle sizes, microstructural properties, oxygen-sensing properties, and humidity effects of the synthesized nano-sized SrTiO3-based oxygen sensors were characterized using X-ray diffraction (XRD), transmission electron microscope, scanning electron microscope (SEM), and gas sensing measurements. Experimental results showed that the particle size of the powders was milled down to be around 27 nm. The effect of different annealing temperatures (400°C, 500°C, 600°C, 700°C, and 800°C) on the gas sensing properties of the synthesized SrTiO3 sensor from nitrogen to 20% oxygen was characterized. The commercial SrTiO3 devices annealed at 400°C, both with 0-h and 120-h milling time, were used for comparison. The optimal relative resistance (Rnitrogen/R20%oxygen) value of 6.35 is obtained for the synthesized SrTiO3 sample annealed at 400°C and operating at 40°C. This operating temperature is much lower than that of conventional metal oxide semiconducting oxygen gas sensors (300°C-500°C) and SrTiO3 oxygen gas sensors (>700°C). The response and recovery times are 1.6 and 5 min, respectively. The detected range is 1-20% oxygen. The impedance of the synthesized SrTiO3 sensor with annealing at 400°C and operating at 40°C (from 1 mHz to 10 MHz) in 20% oxygen ambient was found to be independent of the relative humidity (dry, 20% RH, 80% RH, near 100% RH). [ABSTRACT FROM PUBLISHER]

A noble type of oxygen-sensitive and electrical-conductive material, ZrO2-based with α-Fe2O3 thick-film gas sensor, was investigated for low operating temperature. Amorphous-like solid solutions of xα-Fe2O3-(1-x)ZrO2 powders were derived using the high-energy ball milling technique, and their physical and microstructural properties were characterized from DTA, XRD, TEM, and XPS. The oxygen gas-sensing properties of the screen-printed thick-film gas sensors fabricated from such mechanically-alloyed materials were characterized systematically. Very good sensing properties were obtained with a relative resistance value of 82 in 20% oxygen, and at a low operating temperature of 320°C. AC impedance spectra and thermally stimulated current were characterized to investigate the conduction properties of the solid solution, 0.2α-Fe2O3-0.8ZrO2, in air and nitrogen (carrier gas), respectively. It was found that the Arrhenius plots of σT versus 1000/T have two distinct gradients corresponding to two activation energies in the high and low temperature regions. The transition temperature occurs at about 320°C that corresponds to an optimal operating temperature of the gas sensor. It is believed that the high oxygen vacancy concentration present in the solid solution, 0.2α-Fe2O3-0.8ZrO2, and the dissociation of the associated oxygen vacancy defect complexes at 320°C are the critical factors for the high relative resistance to oxygen gas at low operating temperature. [ABSTRACT FROM PUBLISHER]