Pythium species from rice roots differ in virulence, host colonization and nutritional profile

Background: Progressive yield decline in Philippine aerobic rice fields has been recently associated with three closely related Pythium spp., P. arrhenomanes, P. graminicola and P. inflatum. To understand their differential virulence towards rice seedlings, we conducted a comparative survey in which three isolates each of P. arrhenomanes, P. graminicola and P. inflatum were selected to investigate host colonization, host responses and carbon utilization profiles using histopathological analyses, phenoarrays, DNA quantifications and gene expression studies. Results: The isolate of the most virulent species, P. arrhenomanes, quickly colonized the outer and inner root tissues of rice seedlings, including the xylem, by which it possibly blocked the water transport and induced severe stunting, wilting and seedling death. The lower virulence of the tested P. graminicola and P. inflatum isolates seemed to be reflected in slower colonization processes, limited invasion of the vascular stele and less systemic spread, in which cell wall fortification appeared to play a role. Progressive hyphal invasions triggered the production of reactive oxygen species (ROS) and phenolic compounds, which was the strongest for the P. arrhenomanes isolate and was delayed or much weaker upon inoculation with the P. inflatum isolate. The necrosis marker OsJamyb seemed faster and stronger induced by the most virulent isolates. Although the isolate of P. inflatum was nutritionally the most versatile, the most virulent Pythium isolate appeared physiologically more adapted to its host, evidenced by its broad amino acid utilization profile, including D-amino acids, L-threonine and hydroxyl-L-proline. The latter two compounds have been implicated in plant defense and their use by P. arrhenomanes could therefore represent a part of its virulence strategy. Conclusions: This study illustrates that the differential virulence of rice-pathogenic P. arrhenomanes, P. graminicola and P. inflatum isolates is related to their root colonization capacity, the intensity of induced root responses and their ability to utilize amino acids in their colonization niche. Accordingly, this paper presents important knowledge concerning rice root infections by oomycetes, which could be helpful to further disentangle virulence tactics of soil-borne pathogens

Pythium spp. affecting aerobic rice cultivation in the Philippines: characterization, virulence strategies and plant defense

Global warming and a continuously rising world population are causing water scarcity for agricultural usage. The traditional rice cultivation in flooded paddy fields consumes tremendous amounts of fresh water and therefore, its sustainability is severely threatened. Since rice paddies provide 75% of the total rice production, this poses a huge problem on the future food security of billions of people mainly living in Asia. Several strategies have been developed to save water in paddy fields, but the breeding for improved upland-adapted rice cultivars seemed the most promising. The International Rice Research Institute (IRRI) in the Philippines and the Upland Rice Laboratory of the Chinese Agricultural University (CAU) in China have developed rice cultivars that, like wheat and maize, can be direct-seeded and grown in non-flooded and non-puddled fields, allowing water-savings up to 50% compared to rice paddies. Being responsive to extra fertilization and irrigation, aerobic rice cultivars yield significantly more than traditional upland cultivars and enable farmers to lower the amounts of irrigation water without affecting productivity. Unfortunately, the aerobic rice system has been suffering from declining yields due to autotoxicity, nematodes and/or nutrient deficiencies in Brazil, Japan and the Philippines. The IRRI has also reported on Pythium spp. in Philippine aerobic rice fields, which seemed to contribute to the observed yield decline upon monocultivation. Since Pythium spp. cause worldwide significant losses in the cultivation of economically important crops and their role in rice seedling disease has been frequently documented, we decided to characterize the Pythium spp. present in Philippine aerobic rice fields and to accurately investigate their interaction with rice seedlings. Ninety-nine Pythium isolates were recovered from four different rice fields on the main island Luzon of the Philippine Archipelago. Using pathogenicity assays and sequence information of the internal transcribed spacer (ITS) region of the ribosomal DNA (rDNA) and β-tubulin gene, five closely related Pythium species could be identified among which three appeared to be associated with progressive yield decline in monocropped aerobic rice fields, namely P. arrhenomanes, P. graminicola and P. inflatum. P. arrhenomanes isolates were the most virulent and reduced rice seedling growth drastically. Moreover, they were frequently recovered from aerobic rice fields, stressing the importance of this species with regard to the occurring yield losses. P. graminicola was less virulent and exhibited intraspecific pathogenic variation that was not linked with variation at the genetic level. P. inflatum isolates were non-pathogenic, except when the infection pressure was high and the infection could proceed within four days post rice seed imbibition. This species showed a higher level of intraspecific genetic variability, but this was again not correlated with the phenotype. Therefore, we suggested that rice-attacking Pythium spp. are probably not host-specific. In compliance with this hypothesis, we discovered that P. arrhenomanes isolates from rice and maize seemed to lack host specificity, questioning the suitability of maize as a candidate for crop rotation in aerobic rice fields. To understand the differential aggressiveness of P. arrhenomanes, P. graminicola and P. inflatum towards rice seedlings, we selected one isolate of each species for a detailed comparative survey on their interaction with rice roots. Histopathological, molecular and phenoarray analyses illustrated that P. arrhenomanes could colonize the entire rice root system, including the vascular stele, more quickly and massively compared to P. graminicola and P. inflatum. Its highly efficient colonization process seemed to be driven by its potential to utilize the most abundant amino acids and sugars in rice exudates and rice tissues, to feed on defense-related compounds in its host and to inhibit or postpone cell wall fortification. This, in combination with its stronger and faster induction of reactive oxygen species (ROS), phenolics and ultimately, necrosis, is probably the reason why P. arrhenomanes is able to induce more pronounced disease symptoms than the other two species. In the second part of this dissertation, we focused on the hormonal network involved in the regulation of rice root responses to Pythium spp.. We first summarized the existing knowledge on the rice and Arabidopsis root immune system, to improve our understanding on biotic stress responses in plant roots. Salicylic acid (SA)- and jasmonic acid (JA)-controlled immune responses appeared to participate in the defense of both monocot and dicots to soil-borne pathogens, irrespective of the pathogen’s lifestyle. ET-mediated immune responses also occur, depending on the plant group or the encountered microorganism. It is well-established that successful pathogens may evade effective immune responses by delivering effectors and hence, perturb hormone homeostasis and induce inappropriate defense responses. Based on ample evidence, we discovered that especially auxins (AUXs), cytokinins (CKs), brassinosteroids (BRs), abscisic acid (ABA) or gibberellins (GAs) might be recruited by soil-borne pathogens to suppress plant immunity and facilitate root invasion, colonization and the development of hypertrophic feeding sites. Through genetic, physiological and pathological analyses we challenged the common assumption that BRs confer resistance against a broad-spectrum of pathogenic microorganisms and elucidated that P. graminicola employs BRs as virulence factors and interferes with the rice BR machinery to antagonize effectual SA- and GA-mediated defenses. Moreover, we proved that the immune-suppressive effect of BRs played downstream of SA biosynthesis, and upstream of the master defense regulators NONEXPRESSOR OF PATHOGENESIS-RELATED GENES1 OsNPR1 and OsWRKY45. GA-directed immune responses appeared counteracted at multiple levels resulting in the indirect stabilization of the rice DELLA protein SLENDER RICE1 (SLR1). Additional experiments with P. graminicola and P. inflatum suggest that manipulation of the steroid homeostasis in rice represents a conserved virulence strategy among rice-pathogenic Pythium spp.. Moreover, our results imply that more aggressive Pythium spp. exert stronger effects on the BR biosynthesis, by which they completely inhibit GA biosynthesis and possibly delay or repress cell wall fortification processes. Aiming to further uncover the hormonal pathways recruited by rice-pathogenic Pythium spp., we explored the effect of exogenous JA and indole-3-acetic acid (IAA) on the disease development upon Pythium inoculation and examined the potential transcriptional reprogramming of several JA- and AUX-responsive genes in Pythium-inoculated rice roots. In contrast to many other root-pathogen interactions, JAs appeared not prominently involved in rice responses to Pythium spp.. Exogenous methyl jasmonate (MeJA) weakly induced resistance upon P. arrhenomanes inoculation, while it slightly promoted disease development in the case of P. graminicola and P. inflatum. The balance between JA signaling and other hormonal cascades is suggested to underpin the different outcomes of an activated JA pathway. Like several other soil-borne pathogens, P. arrhenomanes, P. graminicola and P. inflatum turned out to produce IAA and contrasting results from pathological analyses also unraveled the putative potential of the most virulent species to degrade IAA when it is abundantly present. Along with the strong influence of P. arrhenomanes on AUX signaling, we proposed that Pythium spp. try to maintain optimal IAA levels in their ecological niche to interfere with the AUX signaling cascade in their host and consequently, inflict disease. In conclusion, this dissertation broadened the knowledge concerning rice root infections by oomycetes and helped to further disentangle virulence tactics of soil-borne pathogens

Jasmonate-induced defense mechanisms in the belowground antagonistic interaction between Pythium arrhenomanes and Meloidogyne graminicola in rice

Next to their essential roles in plant growth and development, phytohormones play a central role in plant immunity against pathogens. In this study we studied the previously reported antagonism between the plant-pathogenic oomycete Pythium arrhenomanes and the root-knot nematode Meloidogyne graminicola, two root pathogens that co-occur in aerobic rice fields. In this manuscript, we investigated if the antagonism is related to imbalances in plant hormone levels, which could be involved in activation of plant defense. Hormone measurements and gene expression analyses showed that the jasmonate (JA) pathway is induced early upon P. arrhenomanes infection. Exogenous application of methyl-jasmonate (MeJA) on the plant confirmed that JA is needed for basal defense against both P. arrhenomanes and M. graminicola in rice. Whereas M. graminicola suppresses root JA levels to increase host susceptibility, Pythium inoculation boosts JA in a manner that prohibits JA repression by the nematode in double-inoculated plants. Exogenous MeJA supply phenocopied the defense-inducing capacity of Pythium against the root-knot nematode, whereas the antagonism was weakened in JA-insensitive mutants. Transcriptome analysis confirmed upregulation of JA biosynthesis and signaling genes upon P. arrhenomanes infection, and additionally revealed induction of genes involved in biosynthesis of diterpenoid phytoalexins, consistent with strong activation of the gene encoding the JA-inducible transcriptional regulator DITERPENOID PHYTOALEXIN FACTOR. Altogether, the here-reported data indicate an important role for JA-induced defense mechanisms in this antagonistic interaction. Next to that, our results provide evidence for induced expression of genes encoding ERF83, and related PR proteins, as well as auxin depletion in P. arrhenomanes infected rice roots, which potentially further contribute to the reduced nematode susceptibility seen in double-infected plants

A different type of procedure for a different type of pain

No abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55860/1/22260_ftp.pd

STAT2 signaling restricts viral dissemination but drives severe pneumonia in SARS-CoV-2 infected hamsters

Emergence of SARS-CoV-2 causing COVID-19 has resulted in hundreds of thousands of deaths. In search for key targets of effective therapeutics, robust animal models mimicking COVID-19 in humans are urgently needed. Here, we show that Syrian hamsters, in contrast to mice, are highly permissive to SARS-CoV-2 and develop bronchopneumonia and strong inflammatory responses in the lungs with neutrophil infiltration and edema, further confirmed as consolidations visualized by micro-CT alike in clinical practice. Moreover, we identify an exuberant innate immune response as key player in pathogenesis, in which STAT2 signaling plays a dual role, driving severe lung injury on the one hand, yet restricting systemic virus dissemination on the other. Our results reveal the importance of STAT2-dependent interferon responses in the pathogenesis and virus control during SARS-CoV-2 infection and may help rationalizing new strategies for the treatment of COVID-19 patients. SARS-CoV-2 infection can result in severe lung inflammation and pathology, but host response remains incompletely understood. Here the authors show in Syrian hamsters that STAT2 signaling restricts systemic virus dissemination but also drives severe lung injury, playing a dual role in SARS-CoV-2 infection

Five-Year Longitudinal Follow-Up of Restorative Neurostimulation Shows Durability of Effectiveness in Patients With Refractory Chronic Low Back Pain Associated With Multifidus Muscle Dysfunction

Background: Adults with refractory, mechanical chronic low back pain associated with impaired neuromuscular control of the lumbar multifidus muscle have few treatment options that provide long-term clinical benefit. This study hypothesized that restorative neurostimulation, a rehabilitative treatment that activates the lumbar multifidus muscles to overcome underlying dysfunction, is safe and provides relevant and durable clinical benefit to patients with this specific etiology. Materials and Methods: In this prospective five-year longitudinal follow-up of the ReActiv8-B pivotal trial, participants (N = 204) had activity-limiting, moderate-to-severe, refractory, mechanical chronic low back pain, a positive prone instability test result indicating impaired multifidus muscle control, and no indications for spine surgery. Low back pain intensity (10-cm visual analog scale [VAS]), disability (Oswestry Disability Index), and quality of life (EuroQol's “EQ-5D-5L” index) were compared with baseline and following the intent-to-treat principle, with a supporting mixed-effects model for repeated measures that accounted for missing data. Results: At five years (n = 126), low back pain VAS had improved from 7.3 to 2.4 cm (−4.9; 95% CI, −5.3 to −4.5 cm; p &lt; 0.0001), and 71.8% of participants had a reduction of ≥50%. The Oswestry Disability Index improved from 39.1 to 16.5 (−22.7; 95% CI, −25.4 to −20.8; p &lt; 0.0001), and 61.1% of participants had reduction of ≥20 points. The EQ-5D-5L index improved from 0.585 to 0.807 (0.231; 95% CI, 0.195–0.267; p &lt; 0.0001). Although the mixed-effects model attenuated completed-case results, conclusions and statistical significance were maintained. Of 52 subjects who were on opioids at baseline and had a five-year visit, 46% discontinued, and 23% decreased intake. The safety profile compared favorably with neurostimulator treatments for other types of back pain. No lead migrations were observed. Conclusion: Over a five-year period, restorative neurostimulation provided clinically substantial and durable benefits with a favorable safety profile in patients with refractory chronic low back pain associated with multifidus muscle dysfunction. Clinical Trial Registration: The Clinicaltrials.gov registration number for the study is NCT02577354; registration date: October 15, 2016; principal investigator: Christopher Gilligan, MD, Brigham and Women's Hospital, Boston, MA, USA. The study was conducted in Australia (Broadmeadow, New South Wales; Noosa Heads, Queensland; Welland, South Australia; Clayton, Victoria), Belgium (Sint-Niklaas; Wilrijk), The Netherlands (Rotterdam), UK (Leeds, London, Middlesbrough), and USA (La Jolla, CA; Santa Monica, CA; Aurora, CO; Carmel, IN; Indianapolis, IN; Kansas City, KS; Boston, MA; Royal Oak, MI; Durham, NC; Winston-Salem, NC; Cleveland, OH; Providence, RI; Spartanburg, SC; Spokane, WA; Charleston, WV).</p

Monocyte-driven atypical cytokine storm and aberrant neutrophil activation as key mediators of COVID-19 disease severity.

Epidemiological and clinical reports indicate that SARS-CoV-2 virulence hinges upon the triggering of an aberrant host immune response, more so than on direct virus-induced cellular damage. To elucidate the immunopathology underlying COVID-19 severity, we perform cytokine and multiplex immune profiling in COVID-19 patients. We show that hypercytokinemia in COVID-19 differs from the interferon-gamma-driven cytokine storm in macrophage activation syndrome, and is more pronounced in critical versus mild-moderate COVID-19. Systems modelling of cytokine levels paired with deep-immune profiling shows that classical monocytes drive this hyper-inflammatory phenotype and that a reduction in T-lymphocytes correlates with disease severity, with CD8+ cells being disproportionately affected. Antigen presenting machinery expression is also reduced in critical disease. Furthermore, we report that neutrophils contribute to disease severity and local tissue damage by amplification of hypercytokinemia and the formation of neutrophil extracellular traps. Together our findings suggest a myeloid-driven immunopathology, in which hyperactivated neutrophils and an ineffective adaptive immune system act as mediators of COVID-19 disease severity

[pain]Byte VR Storytelling & Classical Ballet

This initial stage paper focuses on the Virtual Reality (VR) experience of the [pain]Byte ballet. The live and VR experience debut October 1st 2017, as part of the Brighton digital festival. Specifically, the development of the VR environment to compliment live performance by using the same choreography to create an option capture element of the VR story telling experience. Reviewing Virtual & Alternative reality gaming & storytelling works and the use of VR for chronic pain management (Chen, Win). Does the VR experience compare to that of the live theatre for the audience? The data visualisations and VR environment will be continuations of the Network Simulator, [data]Storm 2015. We are visualising and comparing the pain pathway system to that of a social network. Linking pain signals to viral/negative messaging for some of the visuals. The main purpose of the pieces links to how “we" present ourselves online, these better or veiled versions of ourselves. For chronic pain sufferers, this can be daily activity in the real world. The paper concludes by identifying some future directions for the research project. The Ballet: [pain]Byte is a data driven dance classical ballet performance and VR (virtual reality) experience. [pain]Byte, is about chronic pain and biomedical engineering, in particular the use of implanted technology - neuromodulation (Al-Kaisey et al). Using data as a medium for storytelling, what it means to be in chronic pain. The live augmented theatre and VR experience research focuses on how an audience’s exposure and understanding are impacted by the difference mediums used for [pain]byte

Comparison of tonic spinal cord stimulation, high-frequency and burst stimulation in patients with complex regional pain syndrome: a double-blind, randomised placebo controlled trial

BACKGROUND: Complex Regional Pain Syndrome (CRPS) is a disabling disease that is sometimes difficult to treat. Although spinal cord stimulation (SCS) can reduce pain in most patients with CRPS, some do not achieve the desired reduction in pain. Moreover, the pain reduction can diminish over time even after an initially successful period of SCS. Pain reduction can be regained by increasing the SCS frequency, but this has not been investigated in a prospective trial. This study compares pain reduction using five SCS frequencies (standard 40 Hz, 500 Hz, 1200 Hz, burst and placebo stimulation) in patients with CRPS to determine which of the modalities is most effective. DESIGN: All patients with a confirmed CRPS diagnosis that have unsuccessfully tried all other therapies and are eligible for SCS, can enroll in this trial (primary implantation group). CRPS patients that already receive SCS therapy, or those previously treated with SCS but with loss of therapeutic effect over time, can also participate (re-implantation group). Once all inclusion criteria are met and written informed consent obtained, patients will undergo a baseline assessment (T0). A 2-week trial with SCS is performed and, if successful, a rechargeable internal pulse generator (IPG) is implanted. For the following 3 months the patient will have standard 40 Hz stimulation therapy before a follow-up assessment (T1) is performed. Those who have completed the T1 assessment will enroll in a 10-week crossover period in which the five SCS frequencies are tested in five periods, each frequency lasting for 2 weeks. At the end of the crossover period, the patient will choose which frequency is to be used for stimulation for an additional 3 months, until the T2 assessment. DISCUSSION: Currently no trials are available that systematically investigate the importance of variation in frequency during SCS in patients with CRPS. Data from this trial will provide better insight as to whether SCS with a higher frequency, or with burst stimulation, results in more effective pain relief. TRIAL REGISTRATION: Current Controlled Trials ISRCTN3665525

Data Network Simulator with Classical Ballet

[data]storm, from readysaltedcode CIC, a data driven dance performance. The development of a social network simulator to demonstrate network growth and message propagation. The underpinning theory of piece stems from social network theory (SNT), graph theory, computer mediated communication (CMC) through to social information processing (SIP) and Computational Thinking (CT). The data visualisation is linked to the physical ballet movements of the dancers, they are a manifestation of the data. The data visualisations on screen link to the live dancers performance patterns and modify to create the visuals and movements of data transmission across a network. Network growth. The first of the simulations shows network growth. Each node in the network represents a user who has the following characteristics: • friendliness (how often they're likely to make friends with another user) • chattiness (how often they send out messages) • category (the subject area they're most interested in) At random time intervals things occur: New users are added to the network depending on the above characteristics, users become friends with each other. All the rules stay the same throughout the simulation. At the same time the dance (ballet) movements and wearables (LEDS) were choreographed/coded to accompany the data visualisation using network mapping techniques. The choreography and wearables elements link to the friendliness and chattiness of each of the nodes in the simulated network. This network simulation is further utilised in the Virus section of the performance using the same rules to simulate how a virus can spread through a network. Further work on this simulation will look at two things 1. Message propagation and viral messaging within a social network like Twitter. 2. Pain signals within the body and how they compare to data transfer within a social network