Le risque de vivre

Myocardial constitutive No production depends on the activity of both endothelial and neuronal NOS (eNOS and nNOS, respectively). Stimulation of myocardial β(3)-adrenergic receptor (β(3)-AR) produces a negative inotropic effect that is dependent on eNOS. We evaluated whether nNOS also plays a role in β(3)-AR signaling and found that the β(3)-AR-mediated reduction in cell shortening and [Ca(2+)](i) transient amplitude was abolished both in eNOS(−/−) and nNOS(−/−) left ventricular (LV) myocytes and in wild type LV myocytes after nNOS inhibition with S-methyl-l-thiocitrulline. LV superoxide (O(2)(˙̄)) production was increased in nNOS(−/−) mice and reduced by l-N(ω)-nitroarginine methyl ester (l-NAME), indicating uncoupling of eNOS activity. eNOS S-glutathionylation and Ser-1177 phosphorylation were significantly increased in nNOS(−/−) myocytes, whereas myocardial tetrahydrobiopterin, eNOS Thr-495 phosphorylation, and arginase activity did not differ between genotypes. Although inhibitors of xanthine oxidoreductase (XOR) or NOX2 NADPH oxidase caused a similar reduction in myocardial O(2)(˙̄), only XOR inhibition reduced eNOS S-glutathionylation and Ser-1177 phosphorylation and restored both eNOS coupled activity and the negative inotropic and [Ca(2+)](i) transient response to β(3)-AR stimulation in nNOS(−/−) mice. In summary, our data show that increased O(2)(˙̄) production by XOR selectively uncouples eNOS activity and abolishes the negative inotropic effect of β(3)-AR stimulation in nNOS(−/−) myocytes. These findings provide unequivocal evidence of a functional interaction between the myocardial constitutive NOS isoforms and indicate that aspects of the myocardial phenotype of nNOS(−/−) mice result from disruption of eNOS signaling

Paracrine signalling by cardiac calcitonin controls atrial fibrogenesis and arrhythmia

Atrial fibrillation, the most common cardiac arrhythmia, is an important contributor to mortality and morbidity, and particularly to the risk of stroke in humans1. Atrial-tissue fibrosis is a central pathophysiological feature of atrial fibrillation that also hampers its treatment; the underlying molecular mechanisms are poorly understood and warrant investigation given the inadequacy of present therapies2. Here we show that calcitonin, a hormone product of the thyroid gland involved in bone metabolism3, is also produced by atrial cardiomyocytes in substantial quantities and acts as a paracrine signal that affects neighbouring collagen-producing fibroblasts to control their proliferation and secretion of extracellular matrix proteins. Global disruption of calcitonin receptor signalling in mice causes atrial fibrosis and increases susceptibility to atrial fibrillation. In mice in which liver kinase B1 is knocked down specifically in the atria, atrial-specific knockdown of calcitonin promotes atrial fibrosis and increases and prolongs spontaneous episodes of atrial fibrillation, whereas atrial-specific overexpression of calcitonin prevents both atrial fibrosis and fibrillation. Human patients with persistent atrial fibrillation show sixfold lower levels of myocardial calcitonin compared to control individuals with normal heart rhythm, with loss of calcitonin receptors in the fibroblast membrane. Although transcriptome analysis of human atrial fibroblasts reveals little change after exposure to calcitonin, proteomic analysis shows extensive alterations in extracellular matrix proteins and pathways related to fibrogenesis, infection and immune responses, and transcriptional regulation. Strategies to restore disrupted myocardial calcitonin signalling thus may offer therapeutic avenues for patients with atrial fibrillation

Crop Updates 2006 - Cereals

This session covers twenty nine papers from different authors: PLENARY 1. The 2005 wheat streak mosaic virus epidemic in New South Wales and the threat posed to the Western Australian wheat industry, Roger Jones and Nichole Burges, Department of Agriculture SOUTH COAST AGRONOMY 2. South coast wheat variety trial results and best options for 2006, Mohammad Amjad, Ben Curtis and Wal Anderson, Department of Agriculture 3. Dual purpose winter wheats to improve productivity, Mohammad Amjad and Ben Curtis, Department of Agriculture 4. South coast large-scale premium wheat variety trials, Mohammad Amjad and Ben Curtis, Department of Agriculture 5. Optimal input packages for noodle wheat in Dalwallinu – Liebe practice for profit trial, Darren Chitty, Agritech Crop Research and Brianna Peake, Liebe Group 6. In-crop risk management using yield prophet®, Harm van Rees1, Cherie Reilly1, James Hunt1, Dean Holzworth2, Zvi Hochman2; 1Birchip Cropping Group, Victoria; 2CSIRO, Toowoomba, Qld 7. Yield Prophet® 2005 – On-line yield forecasting, James Hunt1, Harm van Rees1, Zvi Hochman2,Allan Peake2, Neal Dalgliesh2, Dean Holzworth2, Stephen van Rees1, Trudy McCann1 and Peter Carberry2; 1Birchip Cropping Group, Victoria; 2CSIRO, Toowoomba, Qld 8. Performance of oaten hay varieties in Western Australian environments, Raj Malik and Kellie Winfield, Department of Agriculture 9. Performance of dwarf potential milling varieties in Western Australian environments, Kellie Winfield and Raj Malik, Department of Agriculture 10. Agronomic responses of new wheat varieties in the Southern agricultural region of WA, Brenda Shackley and Judith Devenish, Department of Agriculture 11. Responses of new wheat varieties to management factors in the central agricultural region of Western Australia, Darshan Sharma, Steve Penny and Wal Anderson,Department of Agriculture 12. Sowing time on wheat yield, quality and $ - Northern agricultural region, Christine Zaicou-Kunesch, Department of Agriculture NUTRITION 13.The most effective method of applying phosphorus, copper and zinc to no-till crops, Mike Bolland and Ross Brennan, Department of Agriculture 14. Uptake of K from the soil profile by wheat, Paul Damon and Zed Rengel, Faculty of Natural and Agricultural Sciences, University of Western Australia 15. Reducing nitrogen fertiliser risks, Jeremy Lemon, Department of Agriculture 16. Yield Prophet® and canopy management, Harm van Rees1, Zvi Hochman2, Perry Poulton2, Nick Poole3, Brooke Thompson4, James Hunt1; 1Birchip Cropping Group, Victoria; 2CSIRO, Toowoomba, Qld; 3Foundation for Arable Research, New Zealand; 4Cropfacts, Victoria 17. Producing profits with phosphorus, Stephen Loss, CSBP Ltd, WA 18. Potassium response in cereal cropping within the medium rainfall central wheatbelt, Jeff Russell1, Angie Roe2 and James Eyres2, Department of Agriculture1, Farm Focus Consultants, Northam2 19. Matching nitrogen supply to wheat demand in the high rainfall cropping zone, Narelle Simpson, Ron McTaggart, Wal Anderson, Lionel Martin and Dave Allen, Department of Agriculture DISEASES 20. Comparative study of commercial wheat cultivars and differential lines (with known Pm resistance genes) to powdery mildew response, Hossein Golzar, Manisha Shankar and Robert Loughman, Department of Agriculture 21. On farm research to investigate fungicide applications to minimise leaf disease impacts in wheat – part II, Jeff Russell1, Angie Roe2and James Eyres2, Department of Agriculture1, and Farm Focus Consultants, Northam2 22. Disease resistance update for wheat varieties in WA, Manisha Shankar, John Majewski, Donna Foster, Hossein Golzar, Jamie Piotrowski, Nicole Harry and Rob Loughman, Department of Agriculture 23. Effect of time of stripe rust inoculum arrival on variety response in wheat, Manisha Shankar, John Majewski and Rob Loughman, Department of Agriculture 24. Fungicide seed dressing management of loose smut in Baudin barley, Geoff Thomas and Kith Jayasena, Department of Agriculture PESTS 25. How to avoid insect contamination in cereal grain at harvest, Svetlana Micic, Paul Matson and Tony Dore, Department of Agriculture ABIOTIC 26. Environment – is it as important as variety in sprouting tolerance? Thomas (Ben) Biddulph1, Dr Daryl Mares1, Dr Julie Plummer1 and Dr Tim Setter2, School of Plant Biology, University of Western Australia1 and Department of Agriculture2 27. Frost or fiction, Garren Knell, Steve Curtin and Wade Longmuir, ConsultAg Pty Ltd, WA 28. High moisture wheat harvesting in Esperance 2005, Nigel Metz, South East Premium Wheat Growers Association (SEPWA) Projects Coordinator, Esperance, WA SOILS 28. Hardpan penetration ability of wheat roots, Tina Botwright Acuña and Len Wade, School of Plant Biology, University of Western Australia MARKETS 29. Crop shaping to meet predicted market demands for wheat in the 21st Century, Cindy Mills and Peter Stone,Australian Wheat Board, Melbourn

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Molecular mechanisms of nitric oxide-redox imbalance in atrial fibrillation

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

SARS-CoV-2 E protein: Pathogenesis and potential therapeutic development

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a devastating global pandemic, which has seriously affected human health worldwide. The discovery of therapeutic agents is extremely urgent, and the viral structural proteins are particularly important as potential drug targets. SARS-CoV-2 envelope (E) protein is one of the main structural proteins of the virus, which is involved in multiple processes of the virus life cycle and is directly related to pathogenesis process. In this review, we present the amino acid sequence of the E protein and compare it with other two human coronaviruses. We then explored the role of E protein in the viral life cycle and discussed the pathogenic mechanisms that E protein may be involved in. Next, we summarize the potential drugs against E protein discovered in the current studies. Finally, we described the possible effects of E protein mutation on virus and host. This established a knowledge system of E protein to date, aiming to provide theoretical insights for mitigating the current COVID-19 pandemic and potential future coronavirus outbreaks

In-depth characterization of a mouse model of postoperative atrial fibrillation

Introduction: Postoperative atrial fibrillation (POAF), characterized as AF that arises 1-3 days after surgery, occurs after 30%-40% of cardiac and 10%-20% of non-cardiac surgeries, and is thought to arise due to transient surgery-induced triggers acting on a preexisting vulnerable atrial substrate often associated with inflammation and autonomic nervous system dysfunction. Current experimental studies often rely on human atrial tissue samples, collected during surgery prior to arrhythmia development, or animal models such as sterile pericarditis and atriotomy, which have not been robustly characterized.Aim: To characterize the demographic, electrophysiologic, and inflammatory properties of a POAF mouse model.Methods and Results: A total of 131 wild-type C57BL/6J mice were included in this study. A total of 86 (65.6%) mice underwent cardiothoracic surgery (THOR), which consisted of bi-atrial pericardiectomy with 20 s of aortic cross-clamping; 45 (34.3%) mice underwent a sham procedure consisting of dissection down to but not into the thoracic cavity. Intracardiac pacing, performed 72 h after surgery, was used to assess AF inducibility. THOR mice showed greater AF inducibility (38.4%) compared to Sham mice (17.8%, P = 0.027). Stratifying the cohort by tertiles of age showed that the greatest risk of POAF after THOR compared to Sham occurred in the 12-19-week age group. Stratifying by sex showed that cardiothoracic (CT) surgery increased POAF risk in females but had no significant effect in males. Quantitative polymerase chain reaction of atrial samples revealed upregulation of transforming growth factor beta 1 (TGF-β1) and interleukin 6 (IL6) and 18 (IL18) expression in THOR compared to Sham mice.Conclusion: Here, we demonstrate that the increased POAF risk associated with CT surgery is most pronounced in female and 12-19-week-old mice, and that the expression of inflammatory cytokines is upregulated in the atria of THOR mice prone to inducible AF. One sentence summary: We developed a mouse model of POAF that replicates key features of this condition in humans in terms of incidence and inflammatory indices. We demonstrated that female mice have a greater POAF risk than males, highlighting the importance of considering biological sex in future POAF mouse studies

Evaluation of the role of miR-31-dependent reduction in dystrophin and nNOS on atrial-fibrillation-induced electrical remodelling in man

The management of atrial fibrillation remains a challenge. This condition remodels atrial electrical properties, which promote resistance to treatment. Although remodelling has long been a therapeutic target in atrial fibrillation, its causes remain incompletely understood. We aimed to evaluate the role of miR-31-dependent reduction in dystrophin and neuronal nitric oxide synthase (nNOS, also known as NOS1) on atrial electrical properties and atrial fibrillation inducibility.We recruited 258 patients (209 patients in sinus rhythm and 49 with permanent atrial fibrillation) from the John Radcliffe Hospital, Oxford, UK; written informed consent was obtained from each participant. We also used a goat model of pacing-induced atrial fibrillation (24 with atrial fibrillation vs 20 controls in normal sinus rythm) and nNos-knock-out mice (n=28 compared with 27 wild-type littermates). Gene expression of miR-31, dystrophin, and nNOS was assessed by quantitative RT-PCR; protein content was measured by immunoblotting; NOS activity was evaluated with high-performance liquid chromatography; action potential duration (APD) and rate dependent adaptation were assessed by single-cell patch-clamping, and atrial fibrillation inducibility was evaluated by transoesophageal atrial burst stimulation.We found that atrial-specific upregulation of miR-31 in human atrial fibrillation caused dystrophin (DYS) translational repression and accelerated mRNA degradation of nNOS leading to a profound reduction in atrial DYS and nNOS protein content and in nitric oxide availability. In human atrial myocytes obtained from patients in sinus rhythm, nNOS inhibition was sufficient to recapitulate hallmark features of remodelling induced by atrial fibrillation, such as shortening of APD and loss of APD rate-dependency, but had no effect in patients with atrial fibrillation. In mice, nNos gene deletion or inhibition shortened atrial APD and increased atrial fibrillation inducibility in vivo. Inhibition of miR-31 in human atrial fibrillation recovered DYS and nNOS, and normalised APD and APD rate-dependency. Prevention of miR-31 binding to nNOS 3'UTR recovered both nNOS protein and gene expression but had no effect on the DYS protein or mRNA level (consistent with the mRNA degradation of nNOS by miR-31). Prevention of miR-31 binding to DYS 3'UTR increased DYS protein but not mRNA is consistent with translation repression of DYS by miR-31; recovery of DYS protein increased nNOS protein but not mRNA in keeping with a stabilising effect of DYS on nNOS protein. In goats, a reduction in dystrophin and nNOS protein content was associated with upregulation of miR-31 in the atria but not in the ventricles.The findings suggest that atrial-specific upregulation of miR-31 in human atrial fibrillation is a key mechanism causing atrial loss of dystrophin and nNOS; this loss leads to the electrical phenotype induced by atrial fibrillation.British Heart Foundation (BHF) Programme grant (for BC and XL), BHF Centre of Excellence in Oxford (SR), Leducq Foundation (in part for BC and SR), the European Union's seventh Framework Programme Grant Agree