Toll-7 and Toll-6: central nervous system functions as Drosophila neurotrophin receptors

The Drosophila Toll receptor is crucial for dorsoventral patterning in embryos, and for innate immunity. Toll also functions during central nervous system development, promoting neuronal survival and targeting. There are nine Toll paralogues in Drosophila, and it is unknown whether any of these also function in the CNS. Toll’s ligand, Spz, has an NGF domain. NGF is a vertebrate neurotrophin - a growth factor that regulates the development and function of the nervous system. Drosophila Neurotrophin 1 (DNT1), identified by homology to the vertebrate neurotrophin BDNF, and DNT2 are paralogues of spz. The three DNTs – DNT1, DNT2 and spz – are structural and functional homologues of vertebrate neurotrophins, and they promote neuronal survival, targeting and synaptogenesis in Drosophila. However, the receptors for DNT1 and DNT2 are unknown. Here, using a combination of in situ hybridisations and reporters that drive GFP expression, I investigate the expression of Toll paralogues in the Drosophila nervous system. By generating null mutant flies and gain-of-function transgenic flies, I examine genetic interactions between Tolls and DNTs. I also investigate the rolls of these receptors in adult locomotion, axon targeting and cell survival. Finally, in cell culture, I test whether DNTs can signal through Tolls to activate NFκB

Are online symptoms checkers useful for patients with inflammatory arthritis?

BACKGROUND: Online symptom checkers are increasingly used by patients however there is little published evidence of their effectiveness in real patients. The aim of this study was to evaluate how patients with inflammatory arthritis and inflammatory arthralgia use the internet to look for health information and to assess the advice given and diagnoses suggested by the NHS and WebMD symptom checkers in relation to the patients’ actual diagnoses. METHODS: Thirty-four patients with inflammatory arthritis (rheumatoid arthritis (n = 13), psoriatic arthritis (n = 4), unclassified arthritis (n = 4)) and inflammatory arthralgia (n = 13) newly presenting to a secondary care based clinic were identified using a consecutive sampling approach. Consenting patients were asked questions about their internet use in relation to their presenting symptoms. They then completed the NHS and the WebMD symptom checkers and their answers and the outcomes were recorded. RESULTS: Sixteen patients had previously consulted the internet regarding their symptoms. Neither age nor gender significantly influenced internet usage. Actions advised via the NHS symptom checker were: call an ambulance (n = 11), attend A&E (n = 4), contact your GP straight away (n = 2), see your GP today (n = 6), or see your GP within 36 h (n = 11). The 5 most common differential diagnoses given by Web MD were gout (n = 28), rheumatoid arthritis (n = 24), psoriatic arthritis (n = 22), osteoarthritis (n = 18) and finger dislocation (n = 10). The most common first differential diagnosis was osteoarthritis (n = 12). Only 4 out of 21 patients with inflammatory arthritis were given a first diagnosis of rheumatoid arthritis or psoriatic arthritis. CONCLUSIONS: Our data highlight that help seeking advice given online is often inappropriate and that the diagnoses suggested are frequently inaccurate. Recommendations to seek emergency advice may cause inappropriate healthcare utilization. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12891-016-1189-2) contains supplementary material, which is available to authorized users

PolySTRAND Model of Flow-Induced Nucleation in Polymers

We develop a thermodynamic continuum-level model, polySTRAND, for flow-induced nucleation in polymers suitable for use in computational process modeling. The model’s molecular origins ensure that it accounts properly for flow and nucleation dynamics of polydisperse systems and can be extended to include effects of exhaustion of highly deformed chains and nucleus roughness. It captures variations with the key processing parameters, flow rate, temperature, and molecular weight distribution. Under strong flow, long chains are over-represented within the nucleus, leading to superexponential nucleation rate growth with shear rate as seen in experiments

Interdisciplinarity and insularity in the diffusion of knowledge: an analysis of disciplinary boundaries between philosophy of science and the sciences

Two fundamentally different perspectives on knowledge diffusion dominate debates about academic disciplines. On the one hand, critics of disciplinary research and education have argued that disciplines are isolated silos, within which specialists pursue inward-looking and increasingly narrow research agendas. On the other hand, critics of the silo argument have demonstrated that researchers constantly import and export ideas across disciplinary boundaries. These perspectives have different implications for how knowledge diffuses, how intellectuals gain and lose status within their disciplines, and how intellectual reputations evolve within and across disciplines. We argue that highly general claims about the nature of disciplinary boundaries are counterproductive, and that research on the nature of specific disciplinary boundaries is more useful. To that end, this paper uses a novel publication and citation network dataset and statistical models of citation networks to test hypotheses about the boundaries between philosophy of science and 11 disciplinary clusters. Specifically, we test hypotheses about whether engaging with and being cited by scientific communities outside philosophy of science has an impact on one’s position within philosophy of science. Our results suggest that philosophers of science produce interdisciplinary scholarship, but they tend not to cite work by other philosophers when it is published in journals outside of their discipline. Furthermore, net of other factors, receiving citations from other disciplines has no meaningful impact—positive or negative—on citations within philosophy of science. We conclude by considering this evidence for simultaneous interdisciplinarity and insularity in terms of scientific trading theory and other work on disciplinary boundaries and communication

Toll-6 and Toll-7 function as neurotrophin receptors in the Drosophila melanogaster CNS

Neurotrophin receptors corresponding to vertebrate Trk, p75(NTR) or Sortilin have not been identified in Drosophila, thus it is unknown how neurotrophism may be implemented in insects. Two Drosophila neurotrophins, DNT1 and DNT2, have nervous system functions, but their receptors are unknown. The Toll receptor superfamily has ancient evolutionary origins and a universal function in innate immunity. Here we show that Toll paralogues unrelated to the mammalian neurotrophin receptors function as neurotrophin receptors in fruit-flies. Toll-6 and Toll-7 are expressed in the central nervous system throughout development, and regulate locomotion, motoraxon targeting and neuronal survival. DNT1 and 2 interact genetically with Toll-6 and 7, bind to Toll-7 and 6 promiscuously, and are distributed in vivo in complementary or overlapping domains. We conclude that in fruit-flies, Tolls are not only involved in development and immunity but also in neurotrophism, revealing an unforeseen relationship between the neurotrophin and Toll protein families

Enhancement of Omicron-specific immune responses following bivalent COVID-19 booster vaccination in patients with chronic lymphocytic leukaemia

No abstract available

FLORAL SCENT IN A WHOLE-PLANT CONTEXT Floral volatiles controlling ant behaviour

Summary 1. Ants show complex interactions with plants, both facultative and mutualistic, ranging from grazers through seed predators and dispersers to herders of some herbivores and guards against others. But ants are rarely pollinators, and their visits to flowers may be detrimental to plant fitness. 2. Plants therefore have various strategies to control ant distributions, and restrict them to foliage rather than flowers. These 'filters' may involve physical barriers on or around flowers, or 'decoys and bribes' sited on the foliage (usually extrafloral nectaries -EFNs). Alternatively, volatile organic compounds (VOCs) are used as signals to control ant behaviour, attracting ants to leaves and ⁄ or deterring them from functional flowers. Some of the past evidence that flowers repel ants by VOCs has been equivocal and we describe the shortcomings of some experimental approaches, which involve behavioural tests in artificial conditions. 3. We review our previous study of myrmecophytic acacias, which used in situ experiments to show that volatiles derived from pollen can specifically and transiently deter ants during dehiscence, the effects being stronger in ant-guarded species and more effective on resident ants, both in African and Neotropical species. In these plants, repellence involves at least some volatiles that are known components of ant alarm pheromones, but are not repellent to beneficial bee visitors. 4. We also present new evidence of ant repellence by VOCs in temperate flowers, which is usually pollen-based and active on common European ants. We use these data to indicate that across a wide range of plants there is an apparent trade-off in ant-controlling filter strategies between the use of defensive floral volatiles and the alternatives of decoying EFNs or physical barriers

Kek-6: A truncated-Trk-like receptor for Drosophila neurotrophin 2 regulates structural synaptic plasticity.

Neurotrophism, structural plasticity, learning and long-term memory in mammals critically depend on neurotrophins binding Trk receptors to activate tyrosine kinase (TyrK) signaling, but Drosophila lacks full-length Trks, raising the question of how these processes occur in the fly. Paradoxically, truncated Trk isoforms lacking the TyrK predominate in the adult human brain, but whether they have neuronal functions independently of full-length Trks is unknown. Drosophila has TyrK-less Trk-family receptors, encoded by the kekkon (kek) genes, suggesting that evolutionarily conserved functions for this receptor class may exist. Here, we asked whether Keks function together with Drosophila neurotrophins (DNTs) at the larval glutamatergic neuromuscular junction (NMJ). We tested the eleven LRR and Ig-containing (LIG) proteins encoded in the Drosophila genome for expression in the central nervous system (CNS) and potential interaction with DNTs. Kek-6 is expressed in the CNS, interacts genetically with DNTs and can bind DNT2 in signaling assays and co-immunoprecipitations. Ligand binding is promiscuous, as Kek-6 can also bind DNT1, and Kek-2 and Kek-5 can also bind DNT2. In vivo, Kek-6 is found presynaptically in motoneurons, and DNT2 is produced by the muscle to function as a retrograde factor at the NMJ. Kek-6 and DNT2 regulate NMJ growth and synaptic structure. Evidence indicates that Kek-6 does not antagonise the alternative DNT2 receptor Toll-6. Instead, Kek-6 and Toll-6 interact physically, and together regulate structural synaptic plasticity and homeostasis. Using pull-down assays, we identified and validated CaMKII and VAP33A as intracellular partners of Kek-6, and show that they regulate NMJ growth and active zone formation downstream of DNT2 and Kek-6. The synaptic functions of Kek-6 could be evolutionarily conserved. This raises the intriguing possibility that a novel mechanism of structural synaptic plasticity involving truncated Trk-family receptors independently of TyrK signaling may also operate in the human brain