Canopy Temperature Efficiency as Indicators for Drought Tolerance in Durum Wheat (Triticum Durum Desf.) in Semi Arid Conditions

Durum wheat (Triticum durum Desf.) is one of the more widely cultivated crops in the Mediterranean basin, where drought is the main abiotic stress limiting its production. This study was conducted on the experimental site of station ITGC in Setif, Algeria. The objectives of this study were (i) to determine differences in canopy temperature (CT) and canopy temperature depression (CTD) of different durum wheat under both well-watered and moisture stressed conditions and (ii) to correlate canopy temperature (CT) and canopy temperature depression (CTD) with drought resistance indices value and yield of durum wheat (Triticum durum Desf.) under both conditions. The results of study showed a significant difference between CT and CTD under both conditions and among genotypes. Under dryland conditions, grain yield and mean CTD were correlated positively (r = 0.32**), this correlation is similar to other studies (Blum et al., 1989; Royo et al., 2002). Similar results of correlation between canopy temperature (CT), canopy temperature depression (CTD) and grain yield suggest that the use of CT and CTD in screening for highly tolerant varieties to drought is similar. The significant correlation of CT and CTD with Mean productivity (MP) and Stress tolerance index (STI) suggests that CTD and/or CT can be favorite selection criteria in plant breeding for drought tolerance

Relationship between Flag Leaf Reflectance and Canopy Temperature in Durum Wheat (Triticum durum Desf.) Cultivars under Stressed and Irrigated Conditions

Optical technologies can be developed as practical tools for monitoring plant health by providing unique spectral signatures that can be related to specific plant stresses. The objectives of this study were (i) to determine differences in canopy temperature and leaf reflectance of different durum wheat under both well-watered and moisture stressed conditions and (ii) evaluate the relationships between canopy temperature and leaf reflectance at Red and Blue (RB) wavelength. We use numerical image analysis by Mesurim Pro (Version 3.3) softwarefor estimate leaf reflectance at Red and Blue (RB) wavelength.In this study irrigation treatments affect significantly flag leaf reflectance at RB and canopy temperature. Significant correlations were registered between leaf reflectance and canopy temperature under both conditions irrigated and non irrigated; these best correlations proved the efficiency of using leaf reflectance at RB in screening for drought tolerance in durum wheat cultivars

Durum Wheat (Triticum durum Desf.) Evaluation under Semi Arid Conditions in Eastern Algeria by Path Analysis

This study was aimed to characterize yield components and plant traits related to grain yield. Correlation and path analysis were carried out in durum wheat genotypes grown under irrigated and non-irrigated field conditions during two cropping seasons (2010/2011 and 2011/2012). In the path coefficient analysis, grain yield represented the dependent variable and the number of spikes m-2, number of grains spike-1, kernel weight and number of grains m-2 were the independent ones. Grain yield showed positive phenotypic correlation with number of spikes m-2 and number of grains per m-2under both conditions and during two cropping seasons.Path analysis revealed positive direct effect of 1000- kernels weight, number of spike m-2 and number of grains per spike on grain yield. These results indicated that the 1000- kernels weight and number of spikes m-2 followed by the number of grains per spike and number of grains per m-2 were the traits related to higher grain yield, under irrigated and late season water stress conditions.

Helicobacter pylori Outer Membrane Protein 18 ( Hp1125 ) Induces Dendritic Cell Maturation and Function

Background.  Dendritic cells (DCs) are potent antigen-presenting cells that initiate T-cell responses. A robust adaptive Th1 immune response is crucial to an adaptive (Th2) immune response necessary for vaccine-induced protective immunity against Helicobacter pylori. It has been shown that several outer membrane proteins (Omps) induce a robust antibody response. However, it is also known that the antibodies generated are not protective. Moreover there is great variation in the recognition of high molecular weight H. pylori proteins by sera from infected patients. In contrast to the high molecular weight proteins, serologic responses to small molecular weight proteins provide assessment of current infection with H. pylori and also of its eradication. Aim.  The goal of the study was to analyze the activation of the immune response by a specific low molecular weight Omp that is universally expressed by all H. pylori strains. Therefore, we studied interaction of H. pylori Omp18 with DCs. Methods.  Activation of murine bone marrow-derived DCs and production of cytokines by Omp18 was assessed by fluorescence-activated cell sorter (FACS) for costimulatory markers and ELISA, respectively. The ability of Omp18 stimulated DCs to induce lymphocyte proliferation was measured in a mixed leukocyte reaction. Results.  Omp18 induced higher expression of the B7 (CD80 and CD86) costimulatory molecule after 18 hours indicating processing and presentation of the antigen on the surface by bone marrow-derived DCs. The maturing DCs also secreted significant levels of IL-12, but was 4-fold less than that stimulated by whole bacteria. Omp18-primed DCs induced proliferation and release of IFNγ by syngeneic splenocytes. Conclusion.  We concluded that Omp18 is capable of activating DCs initiating a Th1 immune response.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73882/1/j.1523-5378.2005.00350.x.pd

Radiosensitization by the ATR Inhibitor AZD6738 through Generation of Acentric Micronuclei.

AZD6738 is an orally active ATR inhibitor (ATRi) currently in phase I clinical trials. We found in vitro growth inhibitory activity of this ATRi in a panel of human cancer cell lines. We demonstrated radiosensitization by AZD6738 to single radiation fractions in multiple cancer cell lines independent of both p53 and BRCA2 status by the clonogenic assay. Radiosensitization by AZD6738 to clinically relevant doses of fractionated radiation was demonstrated in vitro using a 3D tumor spheroid model and, in vivo, AZD6738 radiosensitized by abrogating the radiation-induced G2 cell-cycle checkpoint and inhibiting homologous recombination. Mitosis with damaged DNA resulted in mitotic catastrophe as measured by micronucleus formation by live-cell fluorescent-ubiquitination cell-cycle imaging of cell-cycle progression and nuclear morphology. Induction of micronuclei was significantly more prominent for AZD6738 compared with inhibition of the downstream kinase CHK1 alone at isoeffective doses. Micronuclei were characterized as acentric chromosomal fragments, which displayed characteristics of increased DNA damage and cell-cycle dyssynchrony when compared with the primary nucleus. Mol Cancer Ther; 16(1); 25-34. ©2016 AACR

Combined ATR and DNA-PK Inhibition Radiosensitizes Tumor Cells Independently of Their p53 Status.

Head and neck squamous cell carcinoma (HNSCC) is a significant cause of cancer deaths. Cisplatin-based chemoradiotherapy is a standard of care for locally advanced disease. ATR and DNA-PK inhibition (DNA-PKi) are actively being investigated in clinical trials with preclinical data supporting clinical translation as radiosensitizers. Here, we hypothesized that targeting both ATR and DNA-PK with small molecule inhibitors would increase radiosensitization of HNSCC cell lines. Radiosensitization was assessed by Bliss independence analysis of colony survival data. Strong cell cycle perturbing effects were observed with ATR inhibition reversing the G2/M arrest observed for radiation-DNA-PKi. Increased apoptosis in combination groups was measured by Sub-G1 DNA populations. DNA-PKi increased radiation-induced RAD51 and gamma-H2Ax foci, with the addition of ATR inhibition reducing levels of both. A sharp increase in nuclear fragmentation after aberrant mitotic transit appears to be the main driver of decreased survival due to irradiation and dual ATR/DNA-PKi. Dual inhibition of DNA-PK and ATR represents a novel approach in combination with radiation, with efficacy appearing to be independent of p53 status. Due to toxicity concerns, careful assessment is necessary in any future translation of single or dual radiosensitization approaches. Ongoing clinical trials into the ATR inhibitor AZD6738 plus radiation, and the phenotypically similar combination of AZD6738 and the PARP inhibitor olaparib, are likely to be key in ascertaining the toxicity profile of such combinations

An orally bioavailable Chkl inhibitor, CCT244747, sensitizes bladder and head and neck cancer cell lines to radiation

Purpose Chk1 inhibition increases cell sensitivity to both chemotherapy and radiotherapy in several tumour types and is, therefore, a promising anti-cancer approach. Although several Chk1 inhibitors have been developed, their clinical progress has been hampered by low bioavailability and off-target toxicities.Materials and methods We characterized the radiosensitizing activity of CCT244747, the first orally bioavailable Chk1 inhibitor. We used a panel of bladder and head and neck cancer cell lines and monitored the effect of combining CCT244747 with radiation both in in vitro and in vivo models.Results CCT244747 sensitized cancer cell lines to radiation in vitro and resulted in a growth delay in cancer xenograft models associated with a survival benefit. Radiosensitization was elicited by abrogation of the radiation-induced G2 arrest and premature entry into mitosis.Conclusions CCT244747 is a potent and specific Chk1 inhibitor that can be administered orally. It radiosensitizes tumour cell lines and represents a new therapy for clinical application in combination with radiotherapy

Enhanced M1 Macrophage Polarization in Human Helicobacter pylori-Associated Atrophic Gastritis and in Vaccinated Mice

Background: Infection with Helicobacter pylori triggers a chronic gastric inflammation that can progress to atrophy and gastric adenocarcinoma. Polarization of macrophages is a characteristic of both cancer and infection, and may promote progression or resolution of disease. However, the role of macrophages and their polarization during H. pylori infection has not been well defined. Methodology/Principal Findings: By using a mouse model of infection and gastric biopsies from 29 individuals, we have analyzed macrophage recruitment and polarization during H. pylori infection by flow cytometry and real-time PCR. We found a sequential recruitment of neutrophils, eosinophils and macrophages to the gastric mucosa of infected mice. Gene expression analysis of stomach tissue and sorted macrophages revealed that gastric macrophages were polarized to M1 after H. pylori infection, and this process was substantially accelerated by prior vaccination. Human H. pylori infection was characterized by a mixed M1/M2 polarization of macrophages. However, in H. pylori-associated atrophic gastritis, the expression of inducible nitric oxide synthase was markedly increased compared to uncomplicated gastritis, indicative of an enhanced M1 macrophage polarization in this pre-malignant lesion. Conclusions/Significance: These results show that vaccination of mice against H. pylori amplifies M1 polarization of gastric macrophages, and that a similar enhanced M1 polarization is present in human H. pylori-induced atrophic gastritis