Farmland boundary extraction based on the AttMobile-DeeplabV3+ network and least squares fitting of straight lines.

The rapid extraction of farmland boundaries is key to implementing autonomous operation of agricultural machinery. This study addresses the issue of incomplete farmland boundary segmentation in existing methods, proposing a method for obtaining farmland boundaries based on unmanned aerial vehicle (UAV) remote sensing images. The method is divided into two steps: boundary image acquisition and boundary line fitting. To acquire the boundary image, an improved semantic segmentation network, AttMobile-DeeplabV3+, is designed. Subsequently, a boundary tracing function is used to track the boundaries of the binary image. Lastly, the least squares method is used to obtain the fitted boundary line. The paper validates the method through experiments on both crop-covered and non-crop-covered farmland. Experimental results show that on crop-covered and non-crop-covered farmland, the network's intersection over union (IoU) is 93.25% and 93.14%, respectively; the pixel accuracy (PA) for crop-covered farmland is 96.62%. The average vertical error and average angular error of the extracted boundary line are 0.039 and 1.473°, respectively. This research provides substantial and accurate data support, offering technical assistance for the positioning and path planning of autonomous agricultural machinery.

Efficacy of continuous gastric artery infusion chemotherapy in relieving digestive obstruction in advanced gastric cancer.

BACKGROUND: Obstruction or fullness after feeding is common in gastric cancer (GC) patients, affecting their nutritional status and quality of life. Patients with digestive obstruction are generally in a more advanced stage. Existing methods, including palliative gastrectomy, gastrojejunostomy, endoluminal stent, jejunal nutrition tube and intravenous chemotherapy, have limitations in treating these symptoms. AIM: To analyze the efficacy of continuous gastric artery infusion chemotherapy (cGAIC) in relieving digestive obstruction in patients with advanced GC. METHODS: This study was a retrospective study. Twenty-nine patients with digestive obstruction of advanced GC who underwent at least one cycle of treatment were reviewed at The Second Affiliated Hospital of Zhejiang University School of Medicine. The oxaliplatin-based intra-arterial infusion regimen was applied in all patients. Mild systemic chemotherapy was used in combination with local treatment. The clinical response was evaluated by contrast-enhanced computed tomography using Response Evaluation Criteria In Solid Tumors (RECIST) criteria. Digestive tract symptoms and toxic effects were analyzed regularly. A comparison of the Karnofsky Performance Status (KPS) score and Stooler's Dysphagia Score before and after therapy was made. Univariate survival analysis and multivariate survival analysis were also performed to explore the key factors affecting patient survival. RESULTS: All patients finished cGAIC successfully without microcatheter displacement, as confirmed by arteriography. The median follow-up time was 24 mo (95%CI: 20.24-27.76 mo). The overall response rate was 89.7% after cGAIC according to the RECIST criteria. The postoperative Stooler's Dysphagia Score was significantly improved. Twenty-two (75.9%) of the 29 patients experienced relief of digestive obstruction after the first two cycles, and 13 (44.8%) initially unresectable patients were then considered radically resectable. The median overall survival time (mOS) was 16 mo (95%CI: 9.32-22.68 mo). Patients who received radical surgery had a significantly longer mOS than other patients (P value < 0.001). Multivariate Cox regression analysis indicated that radical resection after cGAIC, intravenous chemotherapy after cGAIC, and immunotherapy after cGAIC were independent predictors of mOS. None of the patients stopped treatment because of adverse events. CONCLUSION: cGAIC was effective and safe in relieving digestive obstruction in advanced GC, and it could improve surgical conversion possibility and survival time.

The Effect of Annealing on the Soft Magnetic Properties and Microstructure of Fe82Si2B13P1C3 Amorphous Iron Cores.

This research paper investigated the impact of normal annealing (NA) and magnetic field annealing (FA) on the soft magnetic properties and microstructure of Fe82Si2B13P1C3 amorphous alloy iron cores. The annealing process involved various methods of magnetic field application: transverse magnetic field annealing (TFA), longitudinal magnetic field annealing (LFA), transverse magnetic field annealing followed by longitudinal magnetic field annealing (TLFA) and longitudinal magnetic field annealing followed by transverse magnetic field annealing (LTFA). The annealed samples were subjected to testing and analysis using techniques such as differential scanning calorimetry (DSC), transmission electron microscopy (TEM), X-ray diffraction (XRD), magnetic performance testing equipment and magneto-optical Kerr microscopy. The obtained results were then compared with those of commercially produced Fe80Si9B11. Fe82Si2B13P1C3 demonstrated the lowest loss of P1.4T,2kHz = 8.1 W/kg when annealed in a transverse magnetic field at 370 °C, which was 17% lower than that of Fe80Si9B11. When influenced by the longitudinal magnetic field, the magnetization curve tended to become more rectangular, and the coercivity (B3500A/m) of Fe82Si2B13P1C3 reached 1.6 T, which was 0.05 T higher than that of Fe80Si9B11. During the 370 °C annealing process of the Fe82Si2B13P1C3 amorphous iron core, the internal stress in the strip gradually dissipated, and impurity domains such as fingerprint domains disappeared and aligned with the length direction of the strip. Consequently, wide strip domains with low resistance and easy magnetization were formed, thereby reducing the overall loss of the amorphous iron core.

Sequencing trait-associated mutations to clone wheat rust-resistance gene YrNAM.

Stripe (yellow) rust, caused by Puccinia striiformis f. sp. tritici (Pst), can significantly affect wheat production. Cloning resistance genes is critical for efficient and effective breeding of stripe rust resistant wheat cultivars. One resistance gene (Yr10CG) underlying the Pst resistance locus Yr10 has been cloned. However, following haplotype and linkage analyses indicate the presence of additional Pst resistance gene(s) underlying/near Yr10 locus. Here, we report the cloning of the Pst resistance gene YrNAM in this region using the method of sequencing trait-associated mutations (STAM). YrNAM encodes a non-canonical resistance protein with a NAM domain and a ZnF-BED domain. We show that both domains are required for resistance. Transgenic wheat harboring YrNAM gene driven by its endogenous promoter confers resistance to stripe rust races CYR32 and CYR33. YrNAM is an ancient gene and present in wild wheat species Aegilops longissima and Ae. sharonensis; however, it is absent in most wheat cultivars, which indicates its breeding value.

Advances in the Mining of Disease Resistance Genes from Aegilops tauschii and the Utilization in Wheat.

Aegilops tauschii is one of the malignant weeds that affect wheat production and is also the wild species ancestor of the D genome of hexaploid wheat (Triticum aestivum, AABBDD). It contains many disease resistance genes that have been lost in the long-term evolution of wheat and is an important genetic resource for the mining and utilization of wheat disease resistance genes. In recent years, the genome sequence of Aegilops tauschii has been preliminarily completed, which has laid a good foundation for the further exploration of wheat disease resistance genes in Aegilops tauschii. There are many studies on disease resistance genes in Aegilops tauschii; in order to provide better help for the disease resistance breeding of wheat, this paper analyzes and reviews the relationship between Aegilops tauschii and wheat, the research progress of Aegilops tauschii, the discovery of disease resistance genes from Aegilops tauschii, and the application of disease resistance genes from Aegilops tauschii to modern wheat breeding, providing a reference for the further exploration and utilization of Aegilops tauschii in wheat disease resistance breeding.

The efficacy and safety of continuous intra-arterial infusion neoadjuvant chemotherapy with surgery for locally advanced gastric cancer: a preliminary pilot study.

Background: Neoadjuvant chemotherapy (NAC) followed by R0 resection is regarded as a standard treatment strategy for locally advanced gastric cancer (GC); however, the response to systemic chemotherapy remains unsatisfactory. Continuous intra-arterial infusion chemotherapy (CAIC) is a new method, compared with systematic chemotherapy, it can deliver chemotherapy drugs more accurately, so as to achieve higher surgical conversion rate. This study aimed to explore the efficacy and safety of CAIC in locally advanced GC patients. Methods: In this retrospective pilot study, four patients with histologically confirmed locally advanced GC were identified from a tertiary hospital between May 2018 and December 2018. Clinic stage was belonged to T4N1-3M0 in all cases with potential probability for surgery. All cases received three cycles of NAC by CAIC with oxaliplatin (100 mg on day 1) plus oral S-1 (80 mg/m2/day twice daily for 14 days) (SOX). Contrast-enhanced computed tomography (CT) scans and pathological examinations were performed to evaluate chemotherapeutic response based on the tumor regression grade (TRG) and post-neoadjuvant pathological Tumor Node Metastasis (ypTNM) staging. All cases were regularly followed up with face-to-face interviews at outpatient, abdominal enhanced CT scan and serum tumor markers were be requested at 3-month intervals for up to 1 year postoperatively. Results: The obstruction was significantly alleviated after three cycles of CAIC. Contrast-enhanced CT scans showed decreased tumor volume to some extent, along with lymph node shrinkage after treatment. Radical (R0) resection was achieved in all cases. Histopathological analysis showed tumor downstaging in three cases and upstaging in one case. The tumor response to treatment demonstrated TRG1a in one case, TRG1b in one case, and TRG2 in two cases, with an overall tumor regression rate of 100%. No obvious adverse events or perioperative complications were observed during or following treatment. All cases were alive without tumor recurrence or progression after the 1-year postoperative follow-up. Conclusions: Our study may shed light on super-selective CAIC as an effective method for improving the NAC response in locally advanced GC. Future studies with a larger sample sizes and long-term outcomes are required for a final conclusion.

Effect of Pre-Oxidation Treatment on Corrosion Resistance of FeCoSiBPC Amorphous Alloy.

In this paper, the corrosion resistance of FeCoSiBPC amorphous alloy after pre-oxidation and non-oxidation heat treatment is investigated. The corrosion behaviors of Fe80Co3Si3B10P1C3 amorphous alloys in 1 mol/L NaCl solution were investigated by the electrochemical workstation. The pre-oxidation heat treatment can improve the corrosion resistance of FeCoSiBPC amorphous alloy through an increase in the Ecorr value from -0.736 to -0.668 V, which makes it easy to reach a passive state. The corroded morphology and products of amorphous alloys were tested by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The SEM/TEM analysis showed that, after pre-oxidation treatment, the oxide layer was divided into two layers: the inner layer was amorphous, the outer layer appeared crystalline, and the main oxide was Fe2O3. During the oxidation process, Co and P elements diffused from the inner layer to the outer layer, forming phosphorus and cobalt oxides with high corrosion resistance on the surface of the ribbon, thereby improving the corrosion resistance of the ribbon.

Highly Efficient Magnetic Propulsion of NiFe Nanorod-Based Miniature Swimmers in Three Dimensions.

Magnetically actuated miniature robots have attracted the attention of the scientific community over the past two decades, but the confined workspace of their manipulation system (typically a tri-axial coil or eight electromagnetic coils) and the low efficiency of propulsion have limited their utility. Here, we describe a highly efficient NiFe nanorod-based magnetic miniature swimmer that can be manipulated in 3D spaces using two pairs of coils placed in the x-y horizontal plane. In the new swimmer, the shape symmetry is broken along its body, and the asymmetry in magnetizations is introduced perpendicular to the long axis of its body simultaneously. Such a combined asymmetry design offers favorable controllability in planar magnetic fields, which relaxes the multi-axial coil requirement of the commonly used manipulation system and thus reduces the restriction on the shape and size of the workspaces. The new swimmers display efficient 3D propulsion, with a speed of over 5000 µm s-1 (∼3 body length s-1) and powerful locomotion in biological media such as raw human blood. The fuel utilization efficiency of the swimmer, defined as the ratio of the distance to the net input work in one period, was estimated to be approximately from 10-2 to 10-3 m/J, which is significantly higher than that of magnetic motors with a slender body. Moreover, to provide practical support for further potential use, we demonstrated that the swimmer is able to perform incision operations as a minimally invasive microsurgical tool. Such a swimmer actuation strategy provides a simple and efficient way for 3D manipulation of magnetic miniature robots, offering great potential for future biomedical and other applications.

Wheat TaPUB1 protein mediates ABA response and seed development through ubiquitination.

Abscisic acid (ABA) is an important regulator of plant growth, development, and biotic and abiotic stress responses. Ubiquitination plays important roles in regulating ABA signaling. E3 ligase, a key member in ubiquitination, actively participates in the regulation of biosynthesis, de-repression, and activation of ABA response and degradation of signaling components. In this study, we found that that overexpression of wheat E3 ligase TaPUB1 decreased the sensitivity of wheat seedlings to ABA, whereas TaPUB1-RNA interference (TaPUB1-RNAi) lines increased wheat sensitivity to ABA during germination, root growth, and stomatal opening. TaPUB1 influenced the expression of several ABA-responsive genes, and also interacted with TaPYL4 and TaABI5, which are involved in ABA signal transduction, and promoted their degradation. Additionally, we observed that TaPUB1-OE lines resulted in lower single-split grain numbers, larger seed size, and higher thousand kernel weight, when compared with the WT lines. Contrasting results were obtained for TaPUB1-RNAi lines. It suggests that TaPUB1 acts as a negative regulator in the ABA signaling pathway by interacting with TaPYL4 and TaABI5, subsequently affecting seed development in wheat. In addition, the enhanced abiotic tolerance of overexpression lines due to enhanced photosynthesis and root development may be related to the degradation of TaABI5 by TaPUB1.

Wheat TaPUB1 Regulates Cd Uptake and Tolerance by Promoting the Degradation of TaIRT1 and TaIAA17.

Cadmium (Cd) accumulation in agricultural soils is an increasingly serious problem, as plants absorb Cd, which inhibits their growth and development. Nonetheless, the molecular mechanisms underlying Cd detoxification and accumulation in wheat (Triticum aestivum L.) are unclear. Here, we isolated the U-box E3 ligase TaPUB1 from wheat and reported the functional characterization of TaPUB1 in Cd uptake and tolerance in wheat. Under Cd stress, TaPUB1 overexpression lines displayed higher photosynthetic rates than the wild type; opposite results were observed in the TaPUB1-RNAi lines. In addition, TaPUB1 overexpression lines showed reduced Cd uptake and accumulation, whereas RNAi plants exhibited a significant increase in Cd accumulation after Cd treatment. We further found that TaPUB1 enhanced the resistance of wheat to Cd stress in three ways. First, TaPUB1 interacts with and ubiquitinates TaIRT1, resulting in the inhibition of Cd uptake. Second, TaPUB1 interacts directly with and ubiquitinates TaIAA17, facilitates its degradation, and results in primary root elongation by activating the Aux signaling pathway under Cd stress. Moreover, TaPUB1 decreases ROS accumulation by regulating antioxidant-related gene expression and antioxidant enzyme activity under Cd stress. Thus, a molecular mechanism by which TaPUB1 regulates Cd uptake and tolerance by modulating the stability of TaIRT1 and TaIAA17 proteins was revealed.

Overexpression of isochorismate synthase enhances drought tolerance in barley.

Isochorismate synthase (ICS) is a key enzyme for the synthesis of salicylic acid (SA) in plants. SA mediates plant responses to both biotic and abiotic stresses. In previous studies, we found that overexpression of ICS (ICSOE) or suppression of ICS (ICSRNAi) affected the host response to Fusarium graminearum in barley. However, whether the barley ICS gene plays a role in adapting to abiotic stresses remains to be determined. In the present study, expression of the ICS gene was upregulated when treated with 20 % PEG6000, and ICSOE lines were more drought tolerant than wild type (WT) and ICSRNAi. In addition, the abscisic acid (ABA) levels in the ICSOE lines were higher than those in the WT and ICSRNAi lines under drought stress. High ABA levels significantly reduced Gs and E, which may impact water retention under drought stress. Under drought conditions, the activity of antioxidant enzymes was significantly higher in the ICSOE lines, correlating with a lower levels of reactive oxygen species (ROS) and malondialdehyde (MDA). Enhanced antioxidant competence also contributed to drought tolerance in ICSOE lines. These findings help elucidate the abiotic stress resistance of the ICS pathway in barley.

Procalcitonin Levels in Post TACE Infection.

PURPOSE: This study aimed to evaluate the value of serum procalcitonin (PCT) levels in the diagnosis of abscess and sepsis following transarterial chemoembolization (TACE) therapy among patients with hepatocellular carcinoma (HCC). PATIENTS AND METHODS: In this study, a retrospective review of patient charts was performed in 2221 patients who suffered from hepatocellular carcinoma and had undergone 8656 TACE procedures from January 2012 to January 2018. According to the diagnosis of infection and abscess after TACE, these participants were divided into infection group (group A, n=48) and abscess group (group B, n=35). Group B included subgroup B1 (suffered from liver abscess but no sepsis, n=16) and subgroup B2 (suffered from liver abscess and sepsis, n=19). The main observational indexes included sociodemographic characteristics and laboratory and clinical parameters. RESULTS: The results showed that the mean PCT and C-reactive protein (CRP) levels were higher in group B, but receiver-operating characteristic (ROC) analysis showed low sensitivity and specificity. Only the mean PCT level was higher in subgroup B2 than in subgroup B1 (P<0.001); the ROC analysis had high sensitivity and specificity. However, all other data such as NEUT (neutrophil count) and NEUTP (neutrophil percentage) showed no significant differences. CONCLUSION: Serum PCT level was a promising inexpensive marker for the diagnosis of liver abscess and sepsis following TACE therapy among patients with primary liver cancer. A cutoff level of 5.1 ng/mL for PCT had high sensitivity and specificity in predicting liver abscess with sepsis.

Catastrophic vertebral artery and subclavian artery pseudoaneurysms caused by a fishbone: A case report.

BACKGROUND: Fishbone is the most common esophageal foreign body and tends to migrate after piercing the esophagus to nearby structures. Vascular injury around the esophagus is a serious complication and has a high mortality rate, especially in the case of multiple vascular injuries. CASE SUMMARY: We report an extremely rare case of successive vertebral artery and subclavian artery pseudoaneurysms caused by swallowing a fishbone in a previously healthy 29-year-old female. She was transferred to the emergency department of our hospital because of hemorrhagic shock due to a vertebral artery pseudoaneurysm. We successfully managed the vertebral artery pseudoaneurysm with endovascular stent implantation and the patient's vital signs as well as hemodynamics once became stable. However, the patient died of the second subclavian artery pseudoaneurysm occurring within a short time, which was thought be related to the obvious displacement of the fishbone in the mediastinum. CONCLUSION: Surgery and endovascular stent implantation may be the best choice for treating such complications. Early removal of the fishbone is of great significance in improving the survival of such patients.

Expansin gene TaEXPA2 positively regulates drought tolerance in transgenic wheat (Triticum aestivum L.).

Expansins loosen plant cell walls and are involved in cell enlargement and various abiotic stresses. In previous studies, we cloned the expansin gene TaEXPA2 from the wheat cultivar HF9703. Here, we studied its function and regulation in wheat drought stress tolerance. The results indicated that TaEXPA2-overexpressing wheat plants (OE) exhibited drought tolerant phenotypes, whereas down-regulation of TaEXPA2 by RNA interference (RNAi) resulted in elevated drought sensitivity, as measured by survival rate, photosynthetic rate and water containing ability under drought stress. Overexpression of TaEXPA2 enhanced the antioxidant capacity in wheat plants, via elevation of antioxidant enzyme activity and the increase of the transcripts of some ROS scavenging enzyme-related genes. Further investigation revealed that TaEXPA2 positively influenced lateral root formation under drought conditions. A MYB transcription factor of wheat named TaMPS activates TaEXPA2 expression directly by binding to its promoter. Overexpression of TaMPS in Arabidopsis conferred drought tolerance associated with improved lateral root number, and the close homolog genes of TaEXPA2 were up-regulated in Arabidopsis roots overexpressing TaMPS, which suggest that TaMPS may function as one of the regulator of TaEXPA2 gene expression in the root lateral development under drought stress. These findings suggest that TaEXPA2 positively regulates drought stress tolerance in wheat.

The wheat E3 ligase TaPUB26 is a negative regulator in response to salt stress in transgenic Brachypodium distachyon.

Various abiotic stresses, including high salinity, affect the growth and yield of crop plants. We isolated a gene, TaPUB26, from wheat that encodes a protein containing a U-box domain and armadillo (ARM) repeats. The TaPUB26 transcript levels were upregulated by high salinity, temperature, drought and phytohormones, suggesting the involvement of TaPUB26 in abiotic stress responses. An in vitro ubiquitination assay revealed that TaPUB26 is an E3 ubiquitin ligase. We overexpressed TaPUB26 in Brachypodium distachyon to evaluate TaPUB26 regulation of salt stress tolerance. Compared with the wild type (WT) line, the overexpression lines showed higher salt stress sensitivity under salt stress conditions, but lower chlorophyll (Chl) content, lower photosynthetic levels and overall reduced salt stress tolerance. Additionally, the transgenic plants showed more severe membrane damage, lower antioxidant enzyme activity and more reactive oxygen species (ROS) accumulation than WT plants under salt stress, which might be related to the changes in the expression levels of some antioxidant genes. In addition, the transgenic plants also had higher Na+ and lower K+ contents, thus maintaining a higher cytosolic Na+/K+ ratio in leaves and roots than that in WT plants. Further analysis of the molecular mechanisms showed that TaPUB26 interacted with TaRPT2a, an ATPase subunit of the 26S proteasome complex in wheat. We speculated that TaPUB26 negatively regulates salt stress tolerance by interacting with other proteins, such as TaRPT2a, and that this mechanism involves altered antioxidant competition and cytosolic Na+/K+ equilibrium.

Overexpression of wheat α-mannosidase gene TaMP impairs salt tolerance in transgenic Brachypodium distachyon.

KEY MESSAGE: The TaMP gene from wheat encodes an α-mannosidase induced by salt stress that functions as negative regulator of salt tolerance in plants. Salt stress significantly affects growth and yield of crop plants. The α-mannosidases function in protein folding, trafficking, and endoplasmic reticulum-associated degradation in eukaryotic cells, and they are involved in abiotic stress tolerance in plants. Previously, we identified the α-mannosidase gene TaMP in wheat (Triticum aestivum). In this study, we investigated the function of TaMP in salt stress tolerance. TaMP expression was induced in wheat leaves by salt, drought, abscisic acid, and H2O2 treatments. Overexpressing TaMP in Brachypodium distachyon was associated with a salt-sensitive phenotype. Under salt stress, the overexpressing plants had reduced height, delayed growth status, low photosynthetic rate, decreased survival rate, and diminished yield. Moreover, the overexpression of TaMP aggravated the tendency for ions to become toxic under salt stress by significantly affecting the Na+ and K+ contents in cells. In addition, TaMP could negatively regulate salt tolerance by affecting the antioxidant enzyme system capacity and increasing the reactive oxygen species accumulation. Our study was helpful to understand the underlying physiological and molecular mechanisms of salt stress tolerance in plants.

Initial experience of drug-eluting bead transarterial chemoembolization with CalliSpheres® microspheres in treating liver metastases patients.

BACKGROUND: To evaluate the treatment efficacy, survival, safety profiles and factors affecting the clinical outcomes of drug-eluting bead transarterial chemoembolization (DEB-TACE) in liver metastases patients. METHODS: A total of 39 liver metastases patients underwent DEB-TACE treatment with the novel CalliSpheres® microspheres were retrospectively enrolled. Patients' demographic information, tumor characteristics, history of treatment, laboratory indexes, and treatment procedures were recorded, meanwhile, patients' treatment response survival and adverse events were also evaluated. RESULTS: The rate of complete response, partial response, stable disease and progressive disease of total treated cycles were 1.6%, 34.4%, 54.7% and 9.4%, respectively, and 5.0%, 26.7%, 57.8% and 10.6% of total treated nodules, respectively. Regarding survival, the median progression-free survival (PFS) was 15.3 months (95% CI: 9.7-20.8 months) and the median overall survival was 28.7 months (95% CI: 20.3-37.0 months). Cox's proportional hazard model regression analyses disclosed that previous liver resection was correlated with worse PFS, while combined targeted therapy and disease control rate after the first DEB-TACE were correlated with longer PFS. For safety profiles, biochemical indexes showed that patients' liver function was deteriorated at 1 week after DEB-TACE, but was mainly recovered at 1 month after DEB-TACE. CONCLUSIONS: DEB-TACE is an efficient and safe treatment choice for liver metastases, moreover, strict screening of indications for resection and combined therapy with targeted therapy might improve the efficacy of DEB-TACE.

The involvement of wheat U-box E3 ubiquitin ligase TaPUB1 in salt stress tolerance.

U-box E3 ubiquitin ligases play important roles in the ubiquitin/26S proteasome machinery and in abiotic stress responses. TaPUB1-overexpressing wheat (Triticum aestivum L.) were generated to evaluate its function in salt tolerance. These plants had more salt stress tolerance during seedling and flowering stages, whereas the TaPUB1-RNA interference (RNAi)-mediated knock-down transgenic wheat showed more salt stress sensitivity than the wild type (WT). TaPUB1 overexpression upregulated the expression of genes related to ion channels and increased the net root Na+ efflux, but decreased the net K+ efflux and H+ influx, thereby maintaining a low cytosolic Na+ /K+ ratio, compared with the WT. However, RNAi-mediated knock-down plants showed the opposite response to salt stress. TaPUB1 could induce the expression of some genes that improved the antioxidant capacity of plants under salt stress. TaPUB1 also interacted with TaMP (Triticum aestivum α-mannosidase protein), a regulator playing an important role in salt response in yeast and in plants. Thus, low cytosolic Na+ /K+ ratios and better antioxidant enzyme activities could be maintained in wheat with overexpression of TaPUB1 under salt stress. Therefore, we conclude that the U-box E3 ubiquitin ligase TaPUB1 positively regulates salt stress tolerance in wheat.

Wheat F-box Protein TaFBA1 Positively Regulates Plant Drought Tolerance but Negatively Regulates Stomatal Closure.

The phytohormone abscisic acid (ABA) regulates plant growth and development, as well as responses to various stresses, such as salt and drought. The wheat TaFBA1 gene, which encodes an F-box protein, was previously identified in our laboratory by homologous cloning. We previously found that TaFBA1 expression was induced by ABA and drought stress. In this study, wild-type (WT), TaFBA1 over-expressing (OEs), TaFBA1 homologous gene mutants, and TaFBA1 recovery (Rs) Arabidopsis plants were used. We found that the germination rate, the cotyledon greening rate, the root length, and the photosynthetic performance of TaFBA1 OE plants were better than those of WT under drought and ABA conditions, but mutant plants showed the opposite trend, and overexpression of TaFBA1 in mutants can recover their phenotype. In addition, TaFBA1 was found to be a negative regulator of ABA-induced stoma movement; mRNA transcription of certain ABA signaling-related genes was lower in TaFBA1 OE plants than in WT plants following ABA treatment. Further, we found that TaFBA1 can interact with RCAR1 (an ABA receptor) and ABI5. BiFC assay showed that TaFBA1 may interact with RCAR1 in the plasma membrane. In addition, accumulation of ROS and MDA in TaFBA1 OE plants was lower than that in the WT plants after ABA and drought treatments. Based on these results, we suggest that TaFBA1-regulated ABA insensitivity may be dependent on regulating ABA-mediated gene expression through interacting with RCAR1 and ABI5. Increased antioxidant competence and decreased ROS accumulation may be an important mechanism that underlies improved drought tolerance in TaFBA1 OE plants.

Hypermutations in porcine respiratory and reproductive syndrome virus.

Porcine reproductive and respiratory syndrome (PRRS), which is caused by the PRRS virus (PRRSV), has resulted in large economic losses for the swine industry. The virus has shown remarkable genetic diversity since its discovery. In our study, we investigated mutation types in the evolution of PRRSV for both in vivo and in vitro passaging of the virus. Sequence alignment analysis demonstrated that the most common hypermutations expressed were A→G/U→C and G→A/C→U. The data provide a new theoretical basis for PRRSV evolution.

Le syndrome reproducteur et respiratoire porcin (SRRP), qui est causé par le virus SRRP (VSRRP), a entrainé de grosses pertes économiques à l'industrie porcine. Le virus a démontré une remarquable diversité génétique depuis sa mise en évidence. Dans notre étude, nous avons examiné les types de mutation dans l'évolution du VSRRP lors du passage in vivo et in vitro du virus. L'analyse d'alignement des séquences a démontré que les hypermutations les plus fréquemment exprimées étaient A→G/U→C et G→A/C→U. Ces données fournissent une nouvelle base théorique pour l'évolution du VSRRP.(Traduit par Docteur Serge Messier).