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Xanthomonas oryzae pv. oryzae (Xoo) causes severe bacterial leaf blight (BLB) disease to many Vietnamese major rice cultivars, including the TBR225. OsSWEET13 belongs to group III of the OsSWEET gene family encoding sugar transport proteins, which is considered one of the "susceptibility" genes (S genes) necessary for BLB disease. In this study, the rice cultivar TBR225 was determined to be susceptible to 19/20 Vietnamese Xoo isolates collected from the Northern provinces. Two of the three tested isolates (VXO_60 and VXO_96 isolates) were shown to up-regulate OsSWEET13 upon the Xoo infection of the TBR225 cultivar. The TBR225 OsSWEET13 promoter was isolated for sequencing analysis. The isolated DNA fragment was 615 bp in size, contained an effector binding element (EBE) PthXo2 that was recognized by the type III-secretory transcription activator-like (TAL) proteins of the Xoo. This promoter showed a similarity of more than 99% to the published OsSWEET13 promoter sequences (AP014967.1 and CP018167.1). Our findings are basic for the generation of highyielding rice varieties with resistance to BLB disease by genetic engineering in Vietnam. [ABSTRACT FROM AUTHOR]

The thermal design of natural convection heat sinks is critical to the heat management of electronic devices. In this paper, topology optimization (TO) with a new parameter advancing scheme is employed to study the effect of the heating power, heat source size, allowed volume and material thermal conductivity on the optimized design of natural convection heat sinks. Except for the heating power, the other three factors also play an important role on the optimization results. For the small heating power, TO predicts the tree-like heat sink with many secondary-branches to improve heat conduction, but the specific structure is highly dependent on the heat source size, allowed volume and material thermal conductivity. For the large heating power, TO prefers to produce the taper-like heat sink where the tiny branches fade away to adapt to the strong flow, and the influences of the other three factors are reduced. However, two primary branches that connect the heat source and top corners of the design domain always exist, indicating that they are the most effective ways to improve heat transfer. This work has highlighted the impact of different parameters in TO of natural convection heat sinks and provides a more in-depth understanding of the design guidelines. [ABSTRACT FROM AUTHOR]

Epithelial ovarian cancer (EOC) is the leading cause of deaths due to cancer in women. Adipocytes have been suggested to play a key role in the stimulation of EOC growth. However, the mechanisms underlying the adipocyte-induced EOC proliferation remain undefined. Here, we provide the first evidence that adipocytes induce the activation of sphingosine kinase (SphK) 2 in EOC, which represents a novel pathway that mediates the adipocyte-induced EOC growth. SphK2 inhibition in EOC cells led to a remarkable inhibition of the adipocyte-induced cell proliferation. Moreover, the adipocyte-induced SphK2 activation in EOC cells was extracellular signal-regulated protein kinases (ERK) dependent. Furthermore, silencing SphK2 in EOC significantly inhibited the adipocyte-induced expression of phospho-ERK and c-Myc, two crucial players in EOC growth. Collectively, the current study unraveled a previously unrecognized role of SphK2 in the adipocyteinduced growth-promoting action in EOC, suggesting a novel target for EOC treatment. [ABSTRACT FROM AUTHOR]

TBR225 is one of the most popular commercial rice varieties in Northern Vietnam. However, this variety is highly susceptible to bacterial leaf blight (BLB), a disease caused by Xanthomonas oryzae pv. oryzae (Xoo) which can lead to important yield losses. OsSWEET14 belongs to the SWEET gene family that encodes sugar transporters. Together with other Clade III members, it behaves as a susceptibility (S) gene whose induction by Asian Xoo Transcription-Activator-Like Effectors (TALEs) is absolutely necessary for disease. In this study, we sought to introduce BLB resistance in the TBR225 elite variety. First, two Vietnamese Xoo strains were shown to up-regulate OsSWEET14 upon TBR225 infection. To investigate if this induction is connected with disease susceptibility, nine TBR225 mutant lines with mutations in the AvrXa7, PthXo3 or TalF TALEs DNA target sequences of the OsSWEET14 promoter were obtained using the CRISPR/Cas9 editing system. Genotyping analysis of T0 and T1 individuals showed that mutations were stably inherited. None of the examined agronomic traits of three transgene-free T2 edited lines were significantly different from those of wild-type TBR225. Importantly, one of these T2 lines, harboring the largest homozygous 6-bp deletion, displayed decreased OsSWEET14 expression as well as a significantly reduced susceptibility to a Vietnamese Xoo strains and complete resistance to another one. Our findings indicate that CRISPR/Cas9 editing conferred an improved BLB resistance to a Vietnamese commercial elite rice variety. [ABSTRACT FROM AUTHOR]

We investigate the physical processes behind summer drought in North China by evaluating moisture and energy budget diagnostics and linking them to anomalous large-scale circulation patterns. Moisture budget analysis reveals that summer drought in North China was caused dynamically by reduced vertical moisture advection due to anomalous subsidence and reduced horizontal moisture advection due to anomalous northeasterly winds. Energy budget analysis shows that reduced latent heating was balanced dynamically by decreased dry static energy (DSE) divergence in the middle-toupper troposphere. Linking these results to previous work, we suggest that summer drought in North China was predicated on co-occurrence of the positive phases of the Eurasian (EU) and Pacific-Japan (PJ) teleconnection patterns, potentially modulated by the circumglobal teleconnection (CGT). In the typical case, the negative phase of the CGT intensified the positive EU-related upper-level cyclone. Resulting upper-level cooling and positive surface feedback imposed a cold-core surface anticyclone that weakened with height. By contrast, when the positive phase of the CGT occurred in tandem with the positive EU and PJ patterns, the anticyclone had a warm core and intensified with height. The two cases were unified by strong subsidence but exhibited opposite meridional advection anomalies. In the cold-core cases, meridional moisture inflow was reduced but meridional DSE export was enhanced, further limiting precipitation while maintaining negative thermal anomalies. In the warm-core case, which only occurred once, enhanced meridional inflow of water vapor supplied moisture for sporadic precipitation while reduced meridional DSE export helped to maintain strong static stability. [ABSTRACT FROM AUTHOR]

Sphingosine 1-phosphate (S1P) is an important signaling regulator involved in tumor progression in multiple neoplasms. However, the role of S1P in the pathogenesis of ovarian cancer remains unclear. Herein, we summarize recent advances in understanding the impact of S1P signaling in ovarian cancer progression. S1P, aberrantly produced in ovarian cancer patients, is involved in the regulation of key cellular processes that contribute to ovarian cancer initiation and progression. Moreover, agents that block the S1P signaling pathway inhibit ovarian cancer cell growth or induce apoptosis. Hence, current evidence suggests that S1P may become a potential molecular target for ovarian cancer therapy. [ABSTRACT FROM AUTHOR]

Phylogenetic relationships of the different species in the genus Dendranthema (DC.) Des Moul. were estimated based on chromosome fluorescent in situ hybridization (FISH) with 18S-26S rDNA of Arabidopsis and genomic DNA of Dendranthema as probes. The results revealed that there was no positive correlation between the number of nuclear organization region (NOR) loci and the ploidy of Dendranthema. The exact cytogenetic information of NORs about 14 operational taxonomic units (OTUs) indicated that D. vestitum (Hemsl.) Ling et Shih was closer to the cultivars than other putative species, whereas D. zawadskii (Herb.) Tzvel. was the most distinct. The ambiguously distributed signals of genomic in situ hybridization (GISH) with genomic DNA of lower ploidy species as probes suggested that different genomes among Dendranthema were mixed. The result also indicated the limitation of GISH in studies on the phylogenetic relationships of the different species in this genus Dendranthema and on the origin of cultivated chrysanthemums. Based on these results and previous research, the origin of Chinese cultivated chrysanthemum is discussed. (Managing editor: Wei WANG) [ABSTRACT FROM AUTHOR]

With the development of dye and printing, production wastewater has become one of the most primary pollution sources of water and soil pollution. Most of the dyes are toxic substances, which have the "three-way" effect of carcinogenic, teratogenic and mutagenic. Therefore, it is a very difficult but significant issue to deal with the dye in the wastewater. Here, we report a study on low-cost, high-capacity hydrogels that remove water-soluble dyes. The hydrogel is prepared by crosslinking the β-cyclodextrin and functional monomer: acrylamido and 2-acrylamide-2-methylpropane sulfonic acid by aqueous solution polymerization, meanwhile, alkaline hydrolysis is also an important step for adsorption performance. After alkaline hydrolysis, the amide and sulfonic groups in the hydrogel were converted into carboxylate and sulfonate, which was beneficial to the adsorption of cationic dyes. This polymer could remove 96.58% methylene blue (400 mg/L) and only requires 0.02 wt%. Its maximum adsorption capacity for methylene blue could reach 2638.22 mg/g under equilibrium condition. It is the most powerful adsorbent used to treat dye wastewater, according to the report. It also provides some references for hydrogel treatment of dye wastewater. [Display omitted] • With the introduction of β-CD and graft polymerization with AM and AMPS, a novel hydrogel was successfully prepared and used for MB removal. • The alkaline hydrolysis process of β-CD-A-A hydrogel is beneficial to further improve the adsorption performance of MB. The maximum adsorption capacity of MB can reach 2638.22 mg/g, which is attributed to the internal hydrophobic cavities of β-CD and the adsorption of MB by -COO- and –SO 3 - groups after hydrolysis. • The MB adsorption is mainly due to the affinity of the hydrophobic cavities with the hydrophobic groups on MB molecules and the electrostatic attraction of between -COO- and –SO 3 - groups, and the positively charged groups on MB molecules. • In addition, it was also found that β-CD-A-A has a much higher adsorption capacity for MB under alkaline conditions. [ABSTRACT FROM AUTHOR]

Abstract   FLO/LFY homologue genes were initially characterized as floral meristem identity genes and play a key role in flower development among diverse species. The inflorescence organization of chrysanthemum differs from typical dicotyledons such as Arabidopsis and Antirrhinum as clear sepals are absent, and instead, a pappus, a rudimentary sepal, is formed. To understand the mechanism of reproduction of chrysanthemum at the molecular level, DFL, a FLORICAULA/LEAFY homologous gene, was cloned from Dendranthema lavandulifolium, which is one of the original species of chrysanthemum. The DFL gene consists of a 1,236-bp open reading frame and encodes a putative protein of 412 amino acids, which is 63% identical to LFY and 70% to FLO. The expression patterns of DFL during the flower development were analyzed, and RT-PCR results showed that DFL was strongly expressed in the flower bud. In situ hybridization experiments showed that it is strongly expressed in the inflorescence bract, petal and stamen primordial tissues throughout the inflorescence development. Its expression signals were also detected in stems, leaf primordial tissues and developing inflorescence bracts. [ABSTRACT FROM AUTHOR]

Microparticles (MPs) are small membrane vesicles that are classified into subcategories based on their origin, such as platelet-derived MPs (PMPs), endothelial MPs (EMPs), red blood cell MPs (RMPs) and tissue factor MPs (TF + MPs). Philadelphia chromosome-negative myeloproliferative neoplasms (Ph-MPN) are disorders characterized by abnormal haematopoiesis, thrombosis and the JAK2V617F mutation. MPs are biomarkers for procoagulant state in cancer patients, but their relevance in patients with Ph-MPN was unclear. The present study aimed to measure MP variation in MPN patients and evaluate association with the JAK2V617F mutation and with thrombosis and splenomegaly. In total, 92 patients with MPN were enrolled in the present study, including 60 with essential thrombocythaemia (ET), 20 with polycythaemia vera (PV), and 12 with primary myelofibrosis (PMF). RMPs, PMPs, TF + MPs and EMPs were measured by flow cytometry. The levels of RMPs, PMPs, EMPs and TF + MPs in patients with Ph-MPN were all found to be significantly increased compared with controls (P<0.05). Additionally, the levels of all four types of MPs in the PMF group were significantly increased compared with the PV group (P<0.05), and the level of RMPs in the PMF group was significantly increased compared with the ET group (P<0.05). MP levels were increased in the Ph-MPN patients with thrombosis compared with patients without thrombosis (P<0.05). MP levels were increased in Ph-MPN patients with splenomegaly compared with patients without splenomegaly (P<0.05). The level of PMPs in patients with the JAK2V617F mutation was increased compared with patients without the mutation (P<0.05). In conclusion, the present study showed that MPs are associated with Ph-MPN pathogenesis, and may promote thrombosis. [ABSTRACT FROM AUTHOR]

Background: Soil alkalinity shows significant constraints to crop productivity; however, much less attention has been paid to analyze the effect of soil alkalinity on plant growth and development. Shanrong No. 4 (SR4) is an alkalinity tolerant bread wheat cultivar selected from an asymmetric somatic hybridization between the bread wheat cultivar Jinan 177 (JN177) and tall wheatgrass (Thinopyrum ponticum), which is a suitable material for studying alkalinity tolerant associate genes. Results: The growth of SR4 plant seedlings was less inhibited than that of JN177 when exposed to alkalinity stress conditions. The root cytosolic Na+/K+ ratio in alkalinity stressed SR4 was lower than in JN177, while alkalinity stressed SR4 contained higher level of nutrient elements than in JN177. SR4 plant seedlings accumulated less malondialdehyde (MDA) and reactive oxygen species (ROS), it also showed higher activity of ROS scavenging enzymes than JN177 under alkalinity stress. The root intracellular pH decreased in both alkalinity stressed JN177 and SR4, however, it was much lower in SR4 than in JN177 under alkalinity stress. The transcriptomes of SR4 and JN177 seedlings exposed to alkalinity stress were analyzed by digital gene expression tag profiling method. Alkalinity stress conditions up- and down-regulated a large number of genes in the seedling roots that play the functions in the categories of transcription regulation, signal transduction and protein modification. Conclusions: SR4 expresses a superior tolerance to alkaline stress conditions which is due to its strong absorbing ability for nutrient ions, a strong regulating ability for intracellular and rhizosphere pH and a more active ROS scavenging ability. [ABSTRACT FROM AUTHOR]

Aberrant deposition of fat including free fatty acids in the liver often causes damage to hepatocytes, namely lipotoxicity, which is a key pathogenic event in the development and progression of fatty liver diseases. This study demonstrates a pivotal role of sphingosine kinase 1 (SphK1) in protecting hepatocytes from lipotoxicity. Exposure of primary murine hepatocytes to palmitate resulted in dose-dependent cell death, which was enhanced significantly in Sphk1-deficient cells. In keeping with this, expression of dominant-negative mutant SphK1 also markedly promoted palmitate-induced cell death. In contrast, overexpression of wild-type SphK1 profoundly protected hepatocytes from lipotoxicity. Mechanistically, the protective effect of SphK1 is attributable to suppression of ER stress-mediated proapoptotic pathways, as reflected in the inhibition of IRE1α activation, XBP1 splicing, JNK phosphorylation, and CHOP induction. Of note, SphK1 inhibited the IRE1α pathway by reducing IRE1α expression at the transcriptional level. Moreover, S1P mimicked the effect of SphK1, suppressing IRE1α expression in a receptor-dependent manner. Furthermore, enforced overexpression of IRE1α significantly blocked the protective effect of SphK1 against lipotoxicity. Therefore, this study provides new insights into the role of SphK1 in hepatocyte survival and uncovers a novel mechanism for protection against ER stress-mediated cell death. [ABSTRACT FROM AUTHOR]

The LEAFY (LFY) gene encodes a key transcription factor involved in flower development. In this study, we identified the LFY homolog in Chrysanthemum argyrophyllum L. (CaFL) and sequenced eight clones from a single plant. The cloned genes varied in length (2915-3075 bp) and each had three exons and two introns. The three exons were highly conserved, so intron variance was primarily responsible for gene length differences. The putative CaFL proteins from the eight clones were 99% identical to one another and greater than 97% identical to Chrysanthemum lavandulifolium DFL and Chrysanthemum nankingense CnFL. Intraspecific and interspecific sequence comparisons of the two introns indicated that they varied considerably in both length and sequence composition. Phylogenetic analysis showed that CaFL is more similar to dicotyledonous FLO/LFY-like proteins than to those from monocotyledons or gymnosperms. [ABSTRACT FROM AUTHOR]

As the key enzyme in the biosynthesis of blue flower color pigments, flavonoid 3′,5′‐hydroxylase (F3′5′H) can catalyze the conversion of its major substrates, 2‐S naringenin and dihydrokaempferol, into 3′,4′,5′‐hydroxylated pentahydroxyflavanone and dihydromyricetin, respectively. Unlike other F3′5′Hs belonging to the CYP75A subfamily, Asteraceae‐specific F3′5′Hs belong to the CYP75B subfamily. Furthermore, cineraria F3′5′H expressed in yeast exhibited not only F3′H (flavonoid 3′‐hydroxylase) activity but also F3′5′H activity in vitro. In this study, Southern blotting showed that there was only one copy of a homolog of the F3′5′H gene PCFH in the Pericallis × hybrida genome. This gene could be detected by Northern blot in the primary developmental stages of ligulate florets of the purple‐ and blue‐flowered cultivars, and its transcripts also accumulated in the leaves. Heterologous expression of PCFH could produce new delphinidin derivatives in the corollas of transgenic tobacco plants, increased the content of cyanidin derivatives and lead to the blue‐ and red‐shifting of flower color in T0 generation plants. These results indicate that cineraria F3′5′H exhibited both F3′5′H‐ and F3′H‐activity in vivo. The types and contents of anthocyanins and flower color phenotypes of the T1 generation were similar to those of T0 generation plants. PCFH exhibited stable inheritance and normal functions between generations. This study supplies new evidence to understand Asteraceae‐specific F3′5′Hs and provides important references for the further study of molecular breeding of blue‐flowered chrysanthemums using the PCFH gene. [ABSTRACT FROM AUTHOR]

The article presents findings of a research conducted on cloning and characterization of a gene coding for a major extracellular chitosanase from the koji mold aspergillus oryzae. Under the research, a gene coding for a major extracellular chitosanase was isolated from aspergillus oryzae. It concludes that R3 domain was bound to insoluble powder chitosan, but it did not promote the hydrolysis rate of the chitosanase to any extent.