Genome-wide identification of R2R3-MYB transcription factor subfamily genes involved in salt stress in rice (Oryza sativa L.).

BACKGROUND: R2R3-MYB transcription factors belong to one of the largest gene subfamilies in plants, and they are involved in diverse biological processes. However, the role of R2R3-MYB transcription factor subfamily genes in the response of rice (Oryza sativa L.) to salt stress has been rarely reported. RESULTS: In this study, we performed a genome-wide characterization and expression identification of rice R2R3-MYB transcription factor subfamily genes. We identified a total of 117 R2R3-MYB genes in rice and characterized their gene structure, chromosomal location, and cis-regulatory elements. According to the phylogenetic relationships and amino acid sequence homologies, the R2R3-MYB genes were divided into four groups. qRT-PCR of the R2R3-MYB genes showed that the expression levels of 10 genes significantly increased after 3 days of 0.8% NaCl treatment. We selected a high expression gene OsMYB2-115 for further analysis. OsMYB2-115 was highly expressed in the roots, stem, leaf, and leaf sheath. OsMYB2-115 was found to be localized in the nucleus, and the yeast hybrid assay showed that OsMYB2-115 has transcriptional activation activity. CONCLUSION: This result provides important information for the functional analyses of rice R2R3-MYB transcription factor subfamily genes related to the salt stress response and reveals that OsMYB2-115 may be an important gene associated with salt tolerance in rice.

The OsNAC24-OsNAP protein complex activates OsGBSSI and OsSBEI expression to fine-tune starch biosynthesis in rice endosperm.

Starch accounts for up to 90% of the dry weight of rice endosperm and is a key determinant of grain quality. Although starch biosynthesis enzymes have been comprehensively studied, transcriptional regulation of starch-synthesis enzyme-coding genes (SECGs) is largely unknown. In this study, we explored the role of a NAC transcription factor, OsNAC24, in regulating starch biosynthesis in rice. OsNAC24 is highly expressed in developing endosperm. The endosperm of osnac24 mutants is normal in appearance as is starch granule morphology, while total starch content, amylose content, chain length distribution of amylopectin and the physicochemical properties of the starch are changed. In addition, the expression of several SECGs was altered in osnac24 mutant plants. OsNAC24 is a transcriptional activator that targets the promoters of six SECGs; OsGBSSI, OsSBEI, OsAGPS2, OsSSI, OsSSIIIa and OsSSIVb. Since both the mRNA and protein abundances of OsGBSSI and OsSBEI were decreased in the mutants, OsNAC24 functions to regulate starch synthesis mainly through OsGBSSI and OsSBEI. Furthermore, OsNAC24 binds to the newly identified motifs TTGACAA, AGAAGA and ACAAGA as well as the core NAC-binding motif CACG. Another NAC family member, OsNAP, interacts with OsNAC24 and coactivates target gene expression. Loss-of-function of OsNAP led to altered expression in all tested SECGs and reduced the starch content. These results demonstrate that the OsNAC24-OsNAP complex plays key roles in fine-tuning starch synthesis in rice endosperm and further suggest that manipulating the OsNAC24-OsNAP complex regulatory network could be a potential strategy for breeding rice cultivars with improved cooking and eating quality.

Application of esophageal irradiation stents coated with 125I particles in advanced esophageal cancer.

PURPOSE: The current study was designed to investigate the primary efficacy of esophageal irradiation stents coated with 125I particles in the treatment of elderly patients with advanced esophageal cancer. METHODS: Forty-three elderly patients with advanced esophageal cancer were treated with esophageal stents in the First Affiliated Hospital of Xinxiang Medical University between September 2009 and December 2010. Patients were randomly divided into group A (N=18), treated with irradiation stents, and group B (N=25), treated with ordinary stents. There were no significant intergroup differences in age, lesion length, degree of stenosis, or cancer stage. The stent implantation success rate, relief of dysphagia and complication rate, and survival were assessed. RESULTS: The stent implantation success and short-term dysphagia relief rates were 100.0% in both groups. The mean survival time was 9.8 months and 4.8 months in groups A and B, respectively (p<0.01). However, no significant difference in pain (5/18) or esophageal restenosis (7/25) was found (both p>0.05). CONCLUSION: Dysphagia was relieved and survival was prolonged in advanced esophageal cancer cases treated with 125I particle-coated esophageal stents. This method may be superior to the traditional stents method.

Whole exome sequencing identifies a novel EMD mutation in a Chinese family with dilated cardiomyopathy.

BACKGROUND: Variants in the emerin gene (EMD) were implicated in X-linked recessive Emery-Dreifuss muscular dystrophy (EDMD), characterized by early-onset contractures of tendons, progressive muscular weakness and cardiomyopathy. To date, 223 mutations have been reported in EMD gene and the majority of them caused a predominant skeletal muscular phenotype. In this study, we identified a novel deletion mutation in EMD exon 1, which results in almost a complete loss of emerin protein in a large Chinese family. However, the patients suffered severe dilated cardiomyopathy (DCM) but very mild skeletal muscle disorder. CASE PRESENTATION: Whole exome sequencing (WES) and linkage analysis were performed to identify the underlying mutation in a Chinese DCM family spanning five generations. A missense variation in the GPR50 gene was found co-segregated with the disease phenotype, whereas no functional alteration was detected in the variant GPR50 protein. When analyzing the failure sequences in the exome sequencing data, a novel deletion mutation (c.26_39delATACCGAGCTGACC) in EMD exon 1, was identified in this family. Different from the typical clinical features caused by most reported EMD mutations, patients in our study presented very mild skeletal muscle degeneration that had not been diagnosed until the mutation was found. CONCLUSION: We described a family with rare clinical presentations caused by a novel EMD deletion mutation. Our findings broaden the heterogeneous spectrum of phenotypes attributed to EMD mutations and provide new insight to explain the genotype-phenotype correlations between EMD mutations and EDMD symptoms.

Association of common polymorphisms in ß1-adrenergic receptor with antihypertensive response to carvedilol.

OBJECTIVES: Marked interpatient variability exists in the blood pressure response to carvedilol, a nonselective ß-blocker. Here we evaluated the influence of 4 common polymorphisms in genes of the ß-adrenergic receptor on the antihypertensive efficacy of carvedilol in patients in a double-blinded monotherapy study. METHODS: Eighty-seven subjects with uncomplicated essential hypertensive (49% men; age = 52.2 ± 11.1 years) from Jilin province of China were enrolled in the study, and 5 of them discontinued the treatment due to adverse effects. Both systolic and diastolic blood pressures (DBPs) were measured before and after 7 days of treatment with carvedilol (10 mg/d). Genotypes of the ß1-adrenergic receptor (ADRB1 Ser49Gly and Arg389Gly) and ß2-adrenergic receptor (ADRB2 Gly16Arg and Glu27Gln) were determined by polymerase chain reaction with restriction fragment length polymorphism. RESULTS: Patients homozygous for ADRB1 Arg389 had an approximately 4-fold greater reduction in DBPs than those homozygous for ADRB1 Gly389 (10.61 vs. 2.62 mm Hg, P = 0.013). The ADRB1 haplotype was also a significant predictor of response, as patients with the Gly49Arg389/Ser49Arg389 haplotype pair had a 5.7-fold greater reduction in DBPs than those homozygous for the Ser49Gly389 haplotype (16.11 vs. 2.83 mm Hg, P = 0.0055). An association was not found between ADRB2 polymorphism and carvedilol responsiveness in antihypertensive therapy. CONCLUSIONS: This study provides the first evidence to support that ADRB1 polymorphisms play an important role in the DBPs response to carvedilol treatment in patients with essential hypertension.

Recent Progress in Modification of Polyphenylene Oxide for Application in High-Frequency Communication.

With the rapid development of highly integrated electronic devices and high-frequency microwave communication technology, the parasitic resistance-capacitance (RC) delay and propagation loss severely restrict the development of a high-frequency communication system. Benefiting from its low dielectric constants (Dk) and low dielectric loss factor (Df), polyphenylene oxide (PPO) has attracted widespread attention for its application in the dielectric layers of integrated circuits. However, PPO suffers from a very high melting viscosity, a larger coefficient of thermal expansion than copper wire and poor solvent resistance. Recently, many efforts have focused on the modification of PPO by various means for communication applications. However, review articles focusing on PPO are unexpectedly limited. In this article, the research progress concerning PPO materials in view of the modification of PPO has been summarized. The following aspects are covered: polymerization and design of special chemical structure, low molecular weight PPO and blending with thermosetting resin, hyperbranched PPO, thermosetting PPO and incorporating with fillers. In addition, the advantages and disadvantages of various types of modification methods and their applications are compared, and the possible future development directions are also proposed. It is believed that this review will arouse the interest of the electronics industry because of the detailed summary of the cutting-edge modification technology for PPO.

ARGET-ATRP-Mediated Grafting of Bifunctional Polymers onto Silica Nanoparticles Fillers for Boosting the Performance of High-Capacity All-Solid-State Lithium-Sulfur Batteries with Polymer Solid Electrolytes.

The shuttle effect in lithium-sulfur batteries, which leads to rapid capacity decay, can be effectively suppressed by solid polymer electrolytes. However, the lithium-ion conductivity of polyethylene oxide-based solid electrolytes is relatively low, resulting in low reversible capacity and poor cycling stability of the batteries. In this study, we employed the activator generated through electron transfer atom transfer radical polymerization to graft modify the surface of silica nanoparticles with a bifunctional monomer, 2-acrylamide-2-methylpropanesulfonate, which possesses sulfonic acid groups with low dissociation energy for facilitating Li+ migration and transfer, as well as amide groups capable of forming hydrogen bonds with polyethylene oxide chains. Subsequently, the modified nanoparticles were blended with polyethylene oxide to prepare a solid polymer electrolyte with low crystallinity and high ion conductivity. The resulting electrolyte demonstrated excellent and stable electrochemical performance, with a discharge-specific capacity maintained at 875.2 mAh g-1 after 200 cycles.

Environmentally Tolerant Ionic Hydrogel with High Power Density for Low-Grade Heat Harvesting.

Harvesting low-grade heat by an ionic hydrogel thermoelectric generator (ITEG) into useful electricity is promising to power flexible electronics. However, the poor environmental tolerance of the ionic hydrogel limits its application. Herein, we demonstrate an ITEG with high thermoelectric properties, as well as excellent capabilities of water retention, freezing resistance, and self-regeneration. The obtained ITEG can maintain the original water content at ambient conditions (302 K, 65% relative humidity (RH)) for 7 days and keep unfreezing at a low temperature (253 K). It can even be self-regenerated and recovered to its original state after a water loss in high-temperature conditions. Furthermore, a high ionic Seebeck coefficient of 11.3 mV K-1 and an impressive power density of 167.90 mW m-2 are achieved under a temperature difference of 20 K. A high power density of 60.00 mW m-2 can also be maintained even at 258 K. After drying and regeneration, ITEG-re could even exhibit a higher ionic Seebeck coefficient of 11.8 mV K-1. Successful lighting of light-emitting diodes (LEDs) and charging of capacitors demonstrate the great potential of ITEG to provide continuous energy supply for powering flexible electronics.

OsNAC129 Regulates Seed Development and Plant Growth and Participates in the Brassinosteroid Signaling Pathway.

Grain size and the endosperm starch content determine grain yield and quality in rice. Although these yield components have been intensively studied, their regulatory mechanisms are still largely unknown. In this study, we show that loss-of-function of OsNAC129, a member of the NAC transcription factor gene family that has its highest expression in the immature seed, greatly increased grain length, grain weight, apparent amylose content (AAC), and plant height. Overexpression of OsNAC129 had the opposite effect, significantly decreasing grain width, grain weight, AAC, and plant height. Cytological observation of the outer epidermal cells of the lemma using a scanning electron microscope (SEM) revealed that increased grain length in the osnac129 mutant was due to increased cell length compared with wild-type (WT) plants. The expression of OsPGL1 and OsPGL2, two positive grain-size regulators that control cell elongation, was consistently upregulated in osnac129 mutant plants but downregulated in OsNAC129 overexpression plants. Furthermore, we also found that several starch synthase-encoding genes, including OsGBSSI, were upregulated in the osnac129 mutant and downregulated in the overexpression plants compared with WT plants, implying a negative regulatory role for OsNAC129 both in grain size and starch biosynthesis. Additionally, we found that the expression of OsNAC129 was induced exclusively by abscisic acid (ABA) in seedlings, but OsNAC129-overexpressing plants displayed reduced sensitivity to exogenous brassinolide (BR). Therefore, the results of our study demonstrate that OsNAC129 negatively regulates seed development and plant growth, and further suggest that OsNAC129 participates in the BR signaling pathway.

High-resolution quantitative trait locus mapping for rice grain quality traits using genotyping by sequencing.

Rice is a major food crop that sustains approximately half of the world population. Recent worldwide improvements in the standard of living have increased the demand for high-quality rice. Accurate identification of quantitative trait loci (QTLs) for rice grain quality traits will facilitate rice quality breeding and improvement. In the present study, we performed high-resolution QTL mapping for rice grain quality traits using a genotyping-by-sequencing approach. An F2 population derived from a cross between an elite japonica variety, Koshihikari, and an indica variety, Nona Bokra, was used to construct a high-density genetic map. A total of 3,830 single nucleotide polymorphism markers were mapped to 12 linkage groups spanning a total length of 2,456.4 cM, with an average genetic distance of 0.82 cM. Seven grain quality traits-the percentage of whole grain, percentage of head rice, percentage of area of head rice, transparency, percentage of chalky rice, percentage of chalkiness area, and degree of chalkiness-of the F2 population were investigated. In total, 15 QTLs with logarithm of the odds (LOD) scores >4 were identified, which mapped to chromosomes 6, 7, and 9. These loci include four QTLs for transparency, four for percentage of chalky rice, four for percentage of chalkiness area, and three for degree of chalkiness, accounting for 0.01%-61.64% of the total phenotypic variation. Of these QTLs, only one overlapped with previously reported QTLs, and the others were novel. By comparing the major QTL regions in the rice genome, several key candidate genes reported to play crucial roles in grain quality traits were identified. These findings will expedite the fine mapping of these QTLs and QTL pyramiding, which will facilitate the genetic improvement of rice grain quality.

Primary pulmonary artery rhabdomyosarcoma.

A 69-year-old woman presented with a 4-month history of dyspnoea and radiating upper-right quadrant pain and oedema in her lower extremities for more than 20 days. The ultrasonographic study of the heart revealed the adherence of a substantive hypoechoic mass (73 x 34 mm) to the antelateral wall of the pulmonary artery and resultant pulmonary stenosis. Computed tomographic imaging of the pulmonary artery revealed an irregularly shaped filling defect (approximately 41 x 39 x 59 mm) in the main pulmonary artery. The boundary of the defect was irregular, but demarcation with healthy tissue was clear. After surgical treatment, the histologic and immunohistochemical assays revealed a primary pulmonary artery rhabdomyosarcoma. Pulmonary artery rhabdomyosarcomas are usually misdiagnosed as other pulmonary artery obstructive diseases. There should be a greater focus of clinical attention and resection is the appropriate surgical treatment for such malignant tumours.

Flexible Quasi-Solid-State Composite Electrolyte of Poly (Propylene Glycol)-co-Pentaerythritol Triacry-Late/Li1.5Al0.5Ge1.5(PO4)3 for High-Performance Lithium-Sulfur Battery.

With a higher theoretical specific capacity (1675 mAh g-1) and energy density (2600 Wh kg-1), the lithium-sulfur (Li-S) battery is considered as a promising candidate for a next-generation energy storage device. However, the shuttle effect of polysulfides as well as the large interfacial impedance between brittle solid electrolyte and electrodes lead to the capacity of the Li-S battery decaying rapidly, which limits the practical commercial applications of the Li-S battery. Herein, we reported a facile in situ ultraviolet (UV) curing method to prepare a flexible quasi-solid-state composite electrolyte (QSSCE) of poly(propylene glycol)-co-pentaerythritol triacrylate/Li1.5Al0.5Ge1.5(PO4)3 (PPG-co-PETA/LAGP). By combining the high Li-ion conductivity and mechanical strength of inorganic NASICON-structure LAGP and good flexibility of the crosslinked PPG-co-PETA with nanopore structure, the flexible QSSCE with 66.85 wt% LAGP exhibited high Li-ion conductivity of 5.95 × 10-3 S cm-1 at 25 °C, Li-ion transference number of 0.83 and wide electrochemical window of ~5.0 V (vs. Li/Li+). In addition, the application of QSSCE in the Li-S battery could suppress the shuttle effect of polysulfides effectively, thus the Li-S battery possessed the excellent electrochemical cyclic performance, showing the first-cycle discharge-specific capacity of 1508.1 mAh g-1, the capacity retention of 73.6% after 200 cycles with 0.25 C at 25 °C and good rate performance.

Facile synthesis of copper selenides with different stoichiometric compositions and their thermoelectric performance at a low temperature range.

Copper selenide is widely considered to be a promising candidate for high-performance flexible thermoelectrics; however, most of the reported ZT values of copper selenides are unsatisfactory at a relatively low temperature range. Herein, we utilized some wet chemical methods to synthesize a series of copper selenides. XRD, SEM and TEM characterizations revealed that CuSe, Cu3Se2 and Cu2-x Se were prepared successfully and possessed different morphologies and sizes. Based on the analysis of their thermoelectric properties, Cu2-x Se exhibited the highest Seebeck coefficient and lowest thermal conductivity among the three samples owing to its unique crystal structure. After being sintered at 400 °C under N2 atmosphere, the electrical conductivity of Cu2-x Se enhanced considerable, resulting in a significant improvement of its ZT values from 0.096 to 0.458 at 30 to 150 °C. This result is remarkable for copper selenide-based thermoelectric materials at a relatively low temperature range, indicating its brilliant potential in the field of flexible thermoelectric devices.

The enhancement of photoresponse of an ordered inorganic-organic hybrid architecture by increasing interfacial contacts.

A modified ZnO quantum dot/polythiophene (ZnO/PTh) inorganic-organic hybrid architecture was fabricated by using ordered mesoporous silica (SBA-15) as the retaining template. First, a two-step strategy was developed to synthesize an ordered organic conducting polymer composite (PTh/SBA-15). Then, ZnO quantum dots were in situ formed on the pore walls of the ordered PTh/SBA-15 composite. Photoresponse of the inorganic-organic hybrid was studied with respect to its incident photon to collected electron conversion efficiency (IPCE) and morphology. The presence of SBA-15 proved to be critical for controlling the interfacial morphology and hence enlarging the interfacial area of the inorganic-organic heterojunction. The proposed approach may act as a key method to open up potential applications in photovoltaic devices.

Enhanced photoresponse of CdS/CMK-3 composite as a candidate for light-harvesting assembly.

Two typical carbon materials (ordered mesoporous carbon and carbon nanotube) were chosen as scaffolds in combination with semiconductor quantum dots (SQDs) for making light-harvesting assemblies. The effects of interfacial morphology on photoelectric performance of the carbon-based heterostructures have been investigated in detail. The enhanced photoresponse shows a strong dependence on the interfacial morphology as a result of direct interfacial contacts between SQDs and carbon materials, which plays a major role in increasing charge generation at the interface and transport pathways for photoinduced electron transfer. The methodology to enhance the photoresponse through tuning interfacial morphology proves to be a potent alternative in fabricating photochemical energy conversion systems.

Evolution of density fluctuation to a lamellar crystal in a poly(trimethylene terephthalate) film revealed by the resonance light scattering technique.

The dynamic process of cold crystallization of amorphous poly(trimethylene terephthalate) (PTT) was investigated with resonance light scattering (RLS). By using an enhanced scattering peak at 329 nm, which was in close proximity to the absorption band of PTT film, density fluctuation due to gradual transition from amorphous to crystalline with increasing temperature was monitored. Accordingly, molecular chains movement and structure evolution in PTT during cold crystallization, in particular, the information about each phase of crystallization, including induction, nucleation, nucleus growth and secondary crystallization, were thoroughly revealed. The experimental results indicated that the kinetics parameters measured by the RLS method were in good agreement with those obtained by differential scanning calorimetry (DSC) and fluorescence spectroscopy. In addition, the RLS method can tell more details of the movement and variation in fine structures than DSC and fluorescence techniques as a result of its significantly enhanced scattering signals, like the orientation fluctuations of rigid segments in the course of glass transition and crystallization induction.

Kinetics of phase separation in polymer blends revealed by resonance light scattering spectroscopy.

In this work, kinetics of phase separation in the blends of polystyrene (PS) and poly(vinyl methyl ether) (PVME) was investigated by a simple and sensitive method, i.e., resonance light scattering (RLS) spectroscopy. Owing to the aggregation of chromophores (phenyl rings) in the systems when phase separation occurred, RLS intensities were drastically enhanced and hence acted as a characteristic indicator. At the early stage of phase separation, two different RLS behaviors corresponding to spinodal decomposition (SD) and nucleation and growth (NG) were observed. The Cahn-Hilliard (C-H) linearization theory was found not applicable for kinetics analysis of the scattering data at lambda < 346 nm due to RLS effect near the absorption band. Based on a decomposition reaction model, the apparent activation energy of SD phase separation was estimated by the Arrhenius equation. In view of its simplicity and sensitivity of measurement, affordability and availability of instrument, and wide application range of polymer blends, RLS proved to be an effective means for characterization of microstructural variation in polymer blends.

[Study on bioavailability of Fe-riched wheat varieties using an in vitro digestion/Caco-2 cell model].

OBJECTIVE: To select the most promising Fe-riched wheat varieties by studying Fe bioavailability from several wheat variety flours so as to provide scientific evidence for further human trials and nutrition target in wheat breeding. METHODS: The Fe bioavailability among 10 Fe-riched wheat flours was assessed using an in vitro/Caco-2 cell culture model. Caco-2 cell ferritin formation was measured as an indicator of Fe utilized by human Caco-2 exposing to tested flour digests. RESULTS: Significant differences were detected in Fe bioavailability among 10 flour varieties, Zhongyou 9507 (from Anyang) and Jingdong 8 with 78% flour yield had the highest Fe bioavailability. CONCLUSION: The two most promising varieties, Zhongyou 9507 (from Anyang) and Jingdong 8 will be further evaluated in human trials to determine their efficacy.

Core-Shell Structure Design of Hollow Mesoporous Silica Nanospheres Based on Thermo-Sensitive PNIPAM and pH-Responsive Catechol-Fe3+ Complex.

A kind of core-shell hybrid nanoparticle comprised of a hollow mesoporous silica nanoparticles (HMS) core and a copolymer shell bearing N-(3,4-dihydroxyphenethyl) methacrylamide (DMA) and N-isopropylacrylamide (NIPAM) as responsive moieties was prepared. Moreover, the factors that could impact the surface morphology and hierarchical porous structure were discussed. In the presence of Fe3+, catechol-Fe3+ complexes were formed to achieve pH-responsive polymer shell, combining with thermal-sensitiveness of poly(N-isopropylacrylamide). Doxorubicin (DOX) was applied as a model drug and the behaviors of its loading/release behaviors were investigated to prove the idea. The results exhibited a significant drug loading capacity of 8.6% and embed efficiency of 94.6% under 1 mg ml-1 DOX/PBS solution. In fact, the loading capacity of drug can be easily improved to as high as 28.0% by increasing the DOX concentration. The vitro cytotoxicity assay also indicated that the as-prepared nanoparticles have no significant cytotoxicity on RAW 264.7 cells. The in vitro experiment showed that the cumulative release of DOX was obviously dependent on the temperature and pH values. This pH/temperature-sensitive hollow mesoporous silica nanosphere is expected to have potential applications in controlled drug release.

Activation-free fabrication of high-surface-area porous carbon nanosheets from conjugated copolymers.

High-surface-area porous carbon nanosheets have been successfully prepared by direct carbonization of graphene oxide sandwiched poly(aniline-co-pyrrole). Benefiting from the distinct structure features of the poly(aniline-co-pyrrole) and its homogeneous deposition on the graphene oxide surface, the surface area of the porous carbon nanosheets is as high as 1606 m2 g-1.