High air humidity dampens salicylic acid pathway and NPR1 function to promote plant disease.

The occurrence of plant disease is determined by interactions among host, pathogen, and environment. Air humidity shapes various aspects of plant physiology and high humidity has long been known to promote numerous phyllosphere diseases. However, the molecular basis of how high humidity interferes with plant immunity to favor disease has remained elusive. Here we show that high humidity is associated with an "immuno-compromised" status in Arabidopsis plants. Furthermore, accumulation and signaling of salicylic acid (SA), an important defense hormone, are significantly inhibited under high humidity. NPR1, an SA receptor and central transcriptional co-activator of SA-responsive genes, is less ubiquitinated and displays a lower promoter binding affinity under high humidity. The cellular ubiquitination machinery, particularly the Cullin 3-based E3 ubiquitin ligase mediating NPR1 protein ubiquitination, is downregulated under high humidity. Importantly, under low humidity the Cullin 3a/b mutant plants phenocopy the low SA gene expression and disease susceptibility that is normally observed under high humidity. Our study uncovers a mechanism by which high humidity dampens a major plant defense pathway and provides new insights into the long-observed air humidity influence on diseases.

Skin dose distributions between Stanford and rotational techniques in total skin electron therapy (TSET).

PURPOSE: Total skin electron therapy (TSET) has proven to be one of the most effective treatments for advanced-stage cutaneous T-cell lymphoma. Two most used techniques are the Stanford six-field and rotational techniques. This study compares patient skin dose distributions as a function of depth between these two techniques. METHODS: The EGSnrc system was used to simulate electron beams and calculate patient dose distributions. The calculations assumed the same patient standing on a platform, and the patient's different postures were ignored for the Stanford technique in the comparison of dose distributions. The skin doses were analyzed as a function of skin depth-dose coverage and evaluated using dose-volume-histograms (DVH). The comparisons were performed in three realistic clinical settings in which dual-field were used for patients treated at extended distances of 316 and 500 cm, and a single field was used at 700 cm. In all cases the realistic patient treatment beam delivery geometry was simulated. RESULTS: Although small dose differences were observed in some local areas, no clinically significant differences were found in the patient 3D dose distributions between the Stanford and rotational techniques. Virtually the same DVH curves between two the techniques were observed for mean dose to skin depth of 0-5, 5-10, and 10-15 mm from the skin surface, respectively. It is found that the skin depth dose coverage is 2 mm shallower for patient treatment at 500 cm compared to at 316 cm due to the additional air attenuation. However, very similar dose coverage and uniformity can be achieved at these two different extended treatment distances by adjusting the thickness of acrylic scatter plate. Adequate thickness of a scattering plate improves the skin dose uniformity. CONCLUSION: Both the Stanford and rotational techniques deliver very similar skin dose coverage in DVH plots, and only small differences are seen in local areas. It is worth to emphasize that the DVH is a graphical representation of the distribution of dose within a structure, and it does not contain spatial information. Therefore, comparison of entire skin dose using DVH may mask some variations at different locations of the surface area. In addition, the comparison did not consider different patient postures of the Stanford technique. Including the different patient postures in the calculation may affect the result of doses to the limbs.

Monte Carlo simulation of Cherenkov imaging for Total Skin Electron Treatment with CT DICOM realistic patient geometry.

This Monte Carlo (MC) simulation study provides an evaluation of dose uniformity in a patient and the difference between dose and Cherenkov distributions, which is invaluable in developing conversion factors to relate observed Cherenkov images to actual dose distributions for TSET patients. This MC simulations with TOPAS is performed using realistic patient geometries obtained with a 3D scanner during total skin electron treatments (TSET) at UPenn. For each treatment posture in the Stanford technique, the differences between Cherenkov photon distributions and dose distributions produced in MC are consistent with the differences observed between a Cherenkov imaging camera and in-vivo dose measurement with OSLD on patient skin. According to MC studies of a flat rectangular PVC board, the difference between Cherenkov and dose is mostly due to the spoiler. This is confirmed by observing consistent dose and Cherenkov distributions in clinical measurements on a PVC board without the spoiler. The accumulated dose and Cherenkov distributions for each patient are obtained by projecting the MC output of the 6 postures of the TSET treatment together onto a finite element model of the patient.

Cherenkov imaging for Total Skin Electron Therapy - an evaluation of dose uniformity.

Total Skin Electron Therapy (TSET) utilizes high-energy electrons to treat cancers on the entire body surface. The otherwise invisible radiation beam can be observed via the optical Cherenkov photons emitted from interaction between the high-energy electron beam and tissue. Cherenkov emission can be used to evaluate the dose uniformity on the surface of the patient in real-time using a time-gated intensified camera system. Each patient was monitored during TSET by in-vivo detectors (IVD) as well as Scintillators. Patients undergoing TSET in various conditions (whole body and half body) were imaged and analyzed. A rigorous methodology for converting Cherenkov intensity to surface dose as products of correction factors, including camera vignette correction factor, incident radiation correction factor, and tissue optical properties correction factor. A comprehensive study has been carried out by inspecting various positions on the patients such as vertex, chest, perineum, shins, and foot relative to the umbilicus point (the prescription point).

Monte Carlo (MC) study of dose distribution and Cherenkov imaging in total skin electron therapy (TSET) with TOPAS.

Malignant tissues can be effectively treated by Total Skin Electron Therapy (TSET) over the entire body surface using 6 MeV electron beams. During the radiation treatment, Cherenkov photons are emitted from the patient's skin, and can potentially be used for in-vivo imaging of the radiation dose distribution. A Monte Carlo (MC) simulation toolkit TOPAS is used to study the generation and propagation of Cherenkov photons that are generated from the interaction of electron radiation with human tissues, and to understand the relationship between the dose distributions and the Cherenkov photon distributions. Validation of MC simulations with experiments are performed at 100 SSD and 500 SSD, and simulations of a patient phantom in realistic clinical treatment setups have been done. These simulations with TOPAS show that the emitted Cherenkov distributions at phantom surfaces closely follow their corresponding dose distributions.

Both combinatorial K4me0-K36me3 marks on sister histone H3s of a nucleosome are required for Dnmt3a-Dnmt3L mediated de novo DNA methylation.

A nucleosome contains two copies of each histone H2A, H2B, H3 and H4. Histone H3 K4me0 and K36me3 are two key chromatin marks for de novo DNA methylation catalyzed by DNA methyltransferases in mammals. However, it remains unclear whether K4me0 and K36me3 marks on both sister histone H3s regulate de novo DNA methylation independently or cooperatively. Here, taking advantage of the bivalent histone H3 system in yeast, we examined the contributions of K4 and K36 on sister histone H3s to genomic DNA methylation catalyzed by ectopically co-expressed murine Dnmt3a and Dnmt3L. The results show that lack of both K4me0 and K36me3 on one sister H3 tail, or lack of K4me0 and K36me3 on respective sister H3s results in a dramatic reduction of 5mC, revealing a synergy of two sister H3s in DNA methylation regulation. Accordingly, the Dnmt3a or Dnmt3L mutation that disrupts the interaction of Dnmt3aADD domain-H3K4me0, Dnmt3LADD domain-H3K4me0, or Dnmt3aPWWP domain-H3K36me3 causes a significant reduction of DNA methylation. These results support the model that each heterodimeric Dnmt3a-Dnmt3L reads both K4me0 and K36me3 marks on one tail of sister H3s, and the dimer of heterodimeric Dnmt3a-Dnmt3L recognizes two tails of sister histone H3s to efficiently execute de novo DNA methylation.

Inhibition of lncRNA Neat1 by catalpol via suppressing transcriptional activity of NF-κB attenuates cardiomyocyte apoptosis.

Oxidative stress is considered as a major pathogenesis in myocardial damage; however, effective therapies are limited so far. The present study aimed to investigate the in vitro antioxidative mechanism of Catalpol in cardiomyocytes. The results indicated that Catalpol attenuated high glucose (HG)-induced apoptosis in mouse cardiomyocytes via significantly downregulating long noncoding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (Neat1) expression. Furthermore, Catalpol downregulated Neat1 expression and attenuated apoptosis by inhibiting production of intracellular reactive oxygen species (ROS) in HG-treated cardiomyocytes. Moreover, Catalpol also suppressed HG-induced degradation of IκBα and the nuclear localization of nulear factor-κB (NF-κB) by decreasing the intracellular ROS levels. Additionally, chromatin immunoprecipitation (ChIP) and dual-luciferase activity assays validated that NF-κB bound to Neat1 promoter to activate Neat1 expression. In summary, these results implied that Catalpol protected mouse cardiomyocytes against oxidative injury at least partly through ROS-NF-κB-Neat1 axis.

Catalpol attenuates cardiomyocyte apoptosis in diabetic cardiomyopathy via Neat1/miR-140-5p/HDAC4 axis.

The cardioprotection of catalpol and its mechanism in diabetic cardiomyopathy (DCM) remains unclear. Here, mouse cardiomyocytes were treated with high glucose (HG) to establish a model of cellular injury induced by HG. In vitro experiments were carried out and confirmed that Catalpol attenuated HG-induced long noncoding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (Neat1) expression in mouse cardiomyocytes. Mechanistically, luciferase reporter analysis indicated that Neat1 could decrease the transcription of miR-140-5p to positively regulate histone deacetylase 4 (HDAC4) expression. Notably, overexpression of miR-140-5p or silencing of HDAC4 rescued Neat1-induced cardiomyocyte apoptosis. DCM was induced in male C57BL/6 mice by intraperitoneal injection with streptozotocin (STZ) combined with a high-fat/high-sugar diet. Further in vivo experiments identified that Catalpol alleviated myocardial damage by regulating Neat1/miR-140-5p/HDAC4 axis in DCM mice. Thus, our results demonstrated that Catalpol could exert cardioprotective effect against DCM via Neat1/miR-140-5p/HDAC4 pathway.

[Effect of blood activating water relieving method on heart functions and serum levels of NT-proBNP in patients with heart failure with normal ejection fraction].

OBJECTIVE: To study the effect of blood activating water relieving method (BAWRM) on heart functions and serum levels of NT-proBNP in patients with heart failure with normal ejection fraction (HFNEF). METHODS: Sixty-four HFNEF patients were admitted to our hospital during January 2011 to June 2012. They were randomly assigned to the treatment group (32 cases) and the control group (32 cases). Patients in the control group received routine Western medical treatment, while those in the treatment group additionally took Chinese medical recipes for activating blood circulation and relieving water retention. Changes of Chinese medical syndromes, E/E', serum NT-proBNP contents were observed between the two groups. RESULTS: Compared with before treatment, their Chinese medical syndromes and E/E' were significantly improved, and serum NT-proBNP contents decreased in the two groups (P < 0.05). Compared with the control group, Chinese medical syndromes, E/E', serum NT-proBNP contents obviously decreased in the treatment group, showing statistical difference (P < 0.05). CONCLUSION: BAWRM was an effective way to improve the diastolic function of HFNEF patients and lower the serum level of NT-proBNP with confirmative efficacy.

MicroRNA319a-targeted Brassica rapa ssp. pekinensis TCP genes modulate head shape in chinese cabbage by differential cell division arrest in leaf regions.

Leafy heads of cabbage (Brassica oleracea), Chinese cabbage (Brassica rapa), and lettuce (Lactuca sativa) are composed of extremely incurved leaves. The shape of these heads often dictates the quality, and thus the commercial value, of these crops. Using quantitative trait locus mapping of head traits within a population of 150 recombinant inbred lines of Chinese cabbage, we investigated the relationship between expression levels of microRNA-targeted Brassica rapa ssp. pekinensis TEOSINTE BRANCHED1, cycloidea, and PCF transcription factor4 (BrpTCP4) genes and head shape. Here, we demonstrate that a cylindrical head shape is associated with relatively low BrpTCP4-1 expression, whereas a round head shape is associated with high BrpTCP4-1 expression. In the round-type Chinese cabbage, microRNA319 (miR319) accumulation and BrpTCP4-1 expression decrease from the apical to central regions of leaves. Overexpression of BrpMIR319a2 reduced the expression levels of BrpTCP4 and resulted in an even distribution of BrpTCP4 transcripts within all leaf regions. Changes in temporal and spatial patterns of BrpTCP4 expression appear to be associated with excess growth of both apical and interveinal regions, straightened leaf tips, and a transition from the round to the cylindrical head shape. These results suggest that the miR319a-targeted BrpTCP gene regulates the round shape of leafy heads via differential cell division arrest in leaf regions. Therefore, the manipulation of miR319a and BrpTCP4 genes is a potentially important tool for use in the genetic improvement of head shape in these crops.

QTL mapping of leafy heads by genome resequencing in the RIL population of Brassica rapa.

Leaf heads of cabbage (Brassica oleracea), Chinese cabbage (B. rapa), and lettuce (Lactuca sativa) are important vegetables that supply mineral nutrients, crude fiber and vitamins in the human diet. Head size, head shape, head weight, and heading time contribute to yield and quality. In an attempt to investigate genetic basis of leafy head in Chinese cabbage (B. rapa), we took advantage of recent technical advances of genome resequencing to perform quantitative trait locus (QTL) mapping using 150 recombinant inbred lines (RILs) derived from the cross between heading and non-heading Chinese cabbage. The resequenced genomes of the parents uncovered more than 1 million SNPs. Genotyping of RILs using the high-quality SNPs assisted by Hidden Markov Model (HMM) generated a recombination map. The raw genetic map revealed some physical assembly error and missing fragments in the reference genome that reduced the quality of SNP genotyping. By deletion of the genetic markers in which recombination rates higher than 20%, we have obtained a high-quality genetic map with 2209 markers and detected 18 QTLs for 6 head traits, from which 3 candidate genes were selected. These QTLs provide the foundation for study of genetic basis of leafy heads and the other complex traits.

A Toll-like receptor 9-mediated pathway stimulates perilipin 3 (TIP47) expression and induces lipid accumulation in macrophages.

Excessive accumulation of lipids in macrophages results in formation of foam cells and is a hallmark of atherosclerosis. The PAT family of proteins has been implicated in this process, but details of their involvement in foam cell formation have not been fully elucidated. One of dominant members of the PAT proteins, perilipin 3 (TIP47), is likely to be involved in such a regulatory mechanism. In this study, we demonstrated that the Toll-like receptor 9 (TLR9)-mediated pathway stimulates perilipin 3 expression and accumulation of lipids, especially triglycerides, in macrophages. Oligodeoxynucleotide (ODN) 1826, a ligand of TLR9, significantly enhanced perilipin 3 expression in RAW264.7 cells, and chloroquine, a TLR9 inhibitor, almost completely inhibited ODN1826-induced perilipin 3 expression. The inhibitors of c-jun NH2-terminal kinase and PI 3-kinase suppressed the level of perilipin 3 mRNA induced by ODN1826. ODN1826 induced the expression of IL-1α and IFNß, both of which increased perilipin 3 expression. Antibodies against these cytokines suppressed the ODN1826-induced perilipin 3 mRNA levels. These results suggest that the expression of perilipin 3 in macrophages is in part regulated through the TLR9-mediated mechanism. Furthermore, ODN1826 increased intracellular lipid accumulation in the presence of oxLDL, which was reduced by perilipin 3 siRNA. Perilipin 3 expression was not stimulated by oxLDL. Depletion of perilipin 3 by siRNA specifically reduced triglyceride content in the cells but not cholesterol content, indicating that perilipin 3 is involved mainly in triglyceride accumulation. In conclusion, the TLR9-mediated pathway facilitates foam cell formation in part through increased expression of perilipin 3.

L-arginine attenuates high glucose-accelerated senescence in human umbilical vein endothelial cells.

OBJECTIVE: Endothelial dysfunction is a key event in the onset and progression of atherosclerosis associated with diabetes. Increasing cell senescence may lead to endothelial dysfunction and contribute to vascular complications. Therefore, we aimed to elucidate the possible role and mechanism of L-arginine in preventing cell senescence induced by high glucose. METHODS: HUVECs were respectively cultured under normal control glucose (5.5mM), high glucose (33mM), co-incubation with L-arginine (800microM)and high glucose, and senescence was identified by beta-galactosidase staining, change of cell cycle and telomerase activity. Akt and eNOS activity was analyzed by western blot. RESULTS: High glucose significantly increased number of beta-galactosidase-positive stained cells, inhibited telomerase activity, increased proportion of cells in the G(0)/G(1) phase and reduced proportion in the S phase, and decreased NO synthesis. L-arginine significantly attenuated these senescent alterations. Furthermore, high glucose induced a decrease in Akt and eNOS activity, and L-arginine prevented the decrease in activity. The PI3K inhibitor LY294002 or eNOS inhibitor L-NAME attenuated anti-senescence effect of L-arginine. CONCLUSION: L-arginine may have an anti-senescence effect via the PI3K/Akt pathway in HUVECs exposed to high glucose and it might be a therapeutic agent for diabetic vascular complications.