Search

Summary The precise spatiotemporal characteristics of subcellular calcium (Ca2+) transients are critical for the physiological processes. Here we report a green Ca2+ sensor called “G-CatchER+” using a protein design to report rapid local ER Ca2+ dynamics with significantly improved folding properties. G-CatchER+ exhibits a superior Ca2+ on rate to G-CEPIA1er and has a Ca2+-induced fluorescence lifetimes increase. G-CatchER+ also reports agonist/antagonist triggered Ca2+ dynamics in several cell types including primary neurons that are orchestrated by IP3Rs, RyRs, and SERCAs with an ability to differentiate expression. Upon localization to the lumen of the RyR channel (G-CatchER+-JP45), we report a rapid local Ca2+ release that is likely due to calsequestrin. Transgenic expression of G-CatchER+ in Drosophila muscle demonstrates its utility as an in vivo reporter of stimulus-evoked SR local Ca2+ dynamics. G-CatchER+ will be an invaluable tool to examine local ER/SR Ca2+ dynamics and facilitate drug development associated with ER dysfunction., Graphical Abstract, Highlights • G-CatchER+ exhibits superior kinetics with 1:1 stoichiometry than G-CEPIA1er • G-CatchER+ captures spatially confined ER Ca2+ dynamics in hippocampal neurons • G-CatchER+-JP45 reports rapid Ca2+ signals adjacent to the junctional SR membrane • G-CatchER+ reports stimulus-evoked SR local Ca2+ dynamics in Drosophila muscle, Biochemistry; cell biology; biophysics

The threat of nuclear exposure is heightened and it is imperative to identify potential countermeasures for acute radiation syndrome. Currently no countermeasures have been approved for prophylactic administration. Effective countermeasures should function to increase survival in the short term as well as to increase the overall prognosis of an exposed individual long term. Here we describe the use of a promising radiation countermeasure, BBT-059, and the results of a long term mouse study (up to 12 months) in the male CD2F1 strain using 60Co gamma irradiation (~0.6 Gy/min, 7.5–12.5 Gy). We report the dose reduction factor of 1.28 for BBT-059 (0.3 mg/kg) compared to control administered 24 h prior to irradiation. In the long term study animals showed accelerated recovery in peripheral blood cell counts, bone marrow colony forming units, sternal cellularity and megakaryocyte numbers in drug treated mice compared to formulation buffer. In addition, increased senescence was observed in the kidneys of animals administered control or drug and exposed to the highest doses of radiation. Decreased levels of E-cadherin, LaminB1 and increased levels of Cyc-D and p21 in spleen lysates were observed in animals administered control. Taken together the results indicate a high level of protection following BBT-059 administration in mice exposed to lethal and supralethal doses of total body gamma-radiation.

BackgroundAzathioprine is a widely used immunosuppressant for the treatment of inflammatory conditions such as systemic lupus erythematosus (SLE), systemic vasculitis, dermatomyositis, and inflammatory bowel disease. However, its use is often limited by myelotoxicity. Variants in the gene encoding thiopurine-S-methyltransferase (TPMT), an enzyme in the metabolic pathway of azathioprine, increase the risk for myelotoxicity1. We know little about the relationship between the genetically predicted expression of TPMT and side effects of azathioprine.ObjectivesTo examine whether genetically predicted expression of TPMT in liver tissue is associated with azathioprine adverse effects.MethodsWe assembled a retrospective cohort of new users taking azathioprine for inflammatory conditions at a tertiary care center. We performed genotyping with Illumina Infinium Expanded Multi-Ethnic Genotyping Array plus custom content data, and we then used Michigan Imputation servers for genetic imputation and PrediXcan models trained with GTEx/Genotype-Tissue Expression Project version 8 data to impute TPMT expression in liver tissue. We prespecified nine groups of phecodes (comprised of ICD9 and ICD10 codes) corresponding to known adverse effects of azathioprine. We then tested the association between the predicted expression of TPMT and these adverse events; for outcomes significant in the Wilcoxon ranksum tests (pTPMT in liver tissue into tertiles and conducted logistic regressions to assess the associations between predicted expression and side effects. We conducted a sensitivity analysis restricted to patients with EHR-reported White race.ResultsThe cohort included 1034 patients (Table 1). Phecodes for 3 side effects—leukopenia (n=29), skin cancer (n=13), and rash (n=52)—were identified as associated with predicted TPMT expression in liver tissue. Of these, cases of side effects attributed to azathioprine were validated by chart review: leukopenia (96.6%; n=28), skin cancer (92.3%; n=12), and rash (9.6%; n=5) and used for analysis. When assessed by tertile of predicted TPMT expression, patients in the highest tertile had lower odds of having leukopenia (OR=0.35, 95%CI: 0.12-0.98, p=0.045) and a trend towards higher odds for skin cancer, but the number of cases was small (OR=3.56, 95%CI: 0.73-17.27, p=0.115). Confirmed cases of rash attributed to azathioprine were too few for meaningful analysis. We found similar results when restricted to patients with reported White race.Table 1.Characteristics of patients by TPMT expressionLowest TertileMiddle TertileHighest TertileN=345N=345N=344Female sex, n (%)228 (66.1)244 (70.7)238 (69.2)EHR-reported White race, n (%)306 (88.7)293 (84.9)290 (84.3)Age, median [IQR]42 [29-58]43 [30-55]46 [30-56]Indication, n (%)Systemic lupus erythematosus38 (11.0)42 (12.2)38 (11.0)Inflammatory bowel disease191 (55.3)185 (53.6)190 (55.2)Other connective tissue disorder/autoimmune92 (26.7)96 (27.8)100 (29.1)Other24 (7.0)22 (6.4)16 (4.7)Verified leukopenia attributed to azathioprine, n (%)14 (4.1)9 (2.6)5 (1.5)Verified skin cancer attributed to azathioprine, n (%)2 (0.6)3 (0.9)7 (2.0)Verified rash attributed to azathioprine, n (%)2 (0.6)3 (0.9)0 (0)ConclusionThis analysis suggests that PrediXcan may be useful for examining the association between gene expression and side effects of medications. Moreover, this approach successfully identified leukopenia as a side effect associated with predicted TPMT expression.AcknowledgementsNone to declare.Disclosure of InterestsNone declared.

As "taste" is a primary driver of food choice, the objective of this study was to understand how the sensory properties of diets relate to energy intake (EI). A database of 720 frequently consumed foods, described by a trained panel for basic tastes (sweetness, saltiness) and fatty mouthfeel, was systematically applied to all foods reportedly consumed in 24hr recalls as part of the 2011-2012 Australian National Nutrition and Physical Activity Survey (n = 12,153 adults and children). Food groups were classified according to the Australian Guide to Healthy Eating, and their contribution to total nutrient and sensory intake estimated. There were significant positive correlations between the nutrient and sensory properties of diets, for example, for adults, EI and fatty mouthfeel r = 0.740; EI and saltiness r = 0.623 and EI and sweetness r = 0.517 (all p 0.01). Core foods (e.g. fruits, vegetables, grains, dairy) can provide similar sensory stimulation whilst being of lower energy content than discretionary foods (e.g. confectionary, snacks). Regression models in adults, controlling for age, sex and BMI, revealed that fatty mouthfeel (β = 0.492), saltiness (β = 0.161) and sweetness (β = 0.138) were significant predictors of EI, explaining 56% variance (p 0.01). Similar results were found for children. Fatty mouthfeel was the primary driver of energy intake but such sensory stimulation can be derived from core (e.g. dairy foods), rather than discretionary foods, at lower energy content.

Scholars, often drawing from and expanding on Michel Foucault’s 2004 Security, Territory, Population, have focused on issues of security and insecurity, sometimes providing a deep history for the c...

The relationship between sensory characteristics of foods, diets and weight status is not well established. However, such knowledge could assist in better understanding food choices and inform strategies to improve diet quality. The objectives of this study were to examine the sensory characteristics of diets varying in healthiness and to explore differences by demographics, weight status and diet quality. Data were captured using the online CSIRO Healthy Diet Score survey, including 38 questions on the frequency and quantity of foods consumed, facilitating the calculation of an overall diet quality score out of 100. Data from 145,975 Australian adults are reported. Sensory characteristics of 105 foods and beverages representative of the survey’s food groups were described using a trained sensory panel in terms of basic tastes, fatty mouthfeel and flavour strength. Average sensory scores (weighted by frequency of consumption) were calculated for each food group question. Reported intake (in serves) was multiplied by the sensory scores for each food group consumed to estimate the total sensory value of the diet. Higher diet quality was associated with higher sweet and bitter scores, but a greater proportion of this sweetness was from healthy core foods rather than discretionary foods. Salty taste tended to be lower in diets of higher quality, and there were no differences in fatty mouthfeel by diet quality. Overall flavour intensity increased with diet quality. For the first time the sensory characteristics of foods pertaining to recommended healthy diets can be described. Consumers, industry and public health could utilise such knowledge to encourage the adoption of higher quality diets.

Food choice is strongly driven by the sensory characteristics of foods with sweet, salty and fatty mouthfeel considered highly palatable and rewarding. Attempts to improve diet quality have not addressed sensory characteristics of diets before. This report describes a data modelling exercise that could underpin a dietary strategy to help support consumption of higher quality diets without compromising sensory preferences. This study used the Australian National Nutrition and Physical Activity Survey data (in 9341 adults) and the CSIRO sensory-diet database. A method was developed to find core food swaps which had a similar sensory profile as discretionary foods. This study investigated the impact of such swaps on energy and nutrient intake and the impact of the swaps on servings of food groups. The modelling resulted in a similar sensory profile of core foods to that of discretionary foods with hardness, sweetness and fatty mouthfeel all within 1-3% but the saltiness approached a 4% change. There was a small (3.6%) increase in energy intake. This swap strategy decreased the intake of risk nutrients such as saturated fat and added sugars, but not sodium, while increasing the intake of beneficial nutrients like calcium, zinc and vitamin C. Results also show that there was an increase in the intake of servings of core food groups such as fruits, grains, and dairy products but little change in vegetables. In conclusion, similar sensory swaps are possible and could underpin a diet strategy, that could be further refined through food appropriateness, to improve quality.

We present a simple theory of a strain pulse propagating as a solitary wave through a continuous two-dimensional population of cells. A critical strain is assumed to trigger a strain transformation, while, simultaneously, cells move as automata to tend to restore a preferred cell density. We consider systems in which the strain transformation is a shape change, a burst of proliferation, or the commencement of growth (which changes the shape of the population sheet), and demonstrate isomorphism among these cases. Numerical and analytical solutions describe a strain pulse whose height does not depend on how the strain disturbance was first launched, or the rate at which the strain transformation is achieved, or the rate constant in the rule for the restorative cell motion. The strain pulse is therefore very stable, surviving the imposition of strong perturbations: it would serve well as a timing signal in development. The automatous wave formulation is simple, with few model parameters. A strong case exists for the presence of a strain pulse during amelogenesis. Quantitative analysis reveals a simple relationship between the velocity of the leading edge of the pulse in amelogenesis and the known speed of migration of ameloblast cells. This result and energy arguments support the depiction of wave motion as an automatous cell response to strain, rather than as a response to an elastic energy gradient. The theory may also contribute to understanding the determination front in somitogenesis, moving fronts of convergent-extension transformation, and mitotic wavefronts in the syncytial drosophila embryo.

Transformations in cell shape and motility triggered by strain cues impinging on individual cells within a large population are shown to offer a distinct alternative to chemical cues as a pathway to periodic patterns or sequential segmentation. Interacting transformations can raise up solitary wave-like strain pulses that propagate across a population, providing the cells all the timing and positional information necessary for templating segmentation. Candidate strain-cued transformations include a cell transforming into a secretory state, wherein it changes the organ's geometry; a change in a cell's shape; the onset of proliferation; and surges in cell motility, being either a change in the rate at which cells minimize density gradients or the onset of positive velocity feedback. If the wave response excited by transformations is assumed to be nonlinear, biologically interesting solution spaces emerge. When multiple transformations are pinned to different strain levels by switching criteria in a nonlinear system, their transformation fronts propagate at different velocities. When positive velocity feedback acts between a pair of such fronts, a cycling system can arise, timed by jumps in the location of one of the pair. The period of the cyclic pattern is approximately λ = 1.43 L excl / e c , where L excl is a length scale related to velocity feedback and e c is the critical strain for the primary (driving) transformation. Remarkably but consistently with one small set of data, λ is independent of the velocity of the pulse system and the type of transformation that drives the system. Reasonable values of e c and the assumption that L excl must be at least the cell width if velocity feedback is effected by discrete cells yield an approximate lower bound for λ, free of adjustable parameters. The lower bound approximately predicts the lengths of rugae that form in palatal development in the mouse, somites that form during body axis extension in a bird embryo, and cell cohorts that form among pre-ameloblasts in the mouse or rat incisor.

The degradation of SiC-based ceramic matrix composites (CMCs) in conditions typical of gas turbine engine operation proceeds via the stress-rupture of fiber bundles. The degradation is accelerated when oxygen and water invade the composite through matrix microcracks and react with fiber coatings and the fibers themselves. We review micromechanical models of the main rate-determining phenomena involved, including the the diffusion of gases and reaction products through matrix microcracks, oxidation of SiC (in both matrix and fibers) leading to the loss of stiffness and strength in exposed fibers, the formation of oxide scale on SiC fiber and along matrix crack surfaces that cause the partial closure of microcracks, and the concomitant and synergistic loss of BN fiber coatings. The micromechanical models could be formulated as time-dependent coupled differential equations in time, which must be solved dynamically, e.g., as an iterated user-defined material element, within a finite element simulation. A paradigm is thus established for incorporating the time-dependent evolution of local material properties according to the local environmental and stress conditions that exist within a material, in a simulation of the damage evolution of a composite component. We exemplify the calibration of typical micromechanical degradation models using thermodynamic data for the oxidation and/or volatilization of BN and SiC by oxygen and water, mechanical test data for the rate of stress-rupture of SiC fibers, and kinetic data for the processes involved in gas permeation through microcracks. We discuss approaches for validating computational simulations that include the micromechanical models of environmental degradation. A special challenge is achieving validated predictions of trends with temperature, which are expected to vary in a complex manner during use.. This article is protected by copyright. All rights reserved.

Transcription factors (TFs) have emerged as essential cell autonomous mediators of subtype specific dendritogenesis; however, the downstream effectors of these TFs remain largely unknown, as are the cellular events that TFs control to direct morphological change. As dendritic morphology is largely dictated by the organization of the actin and microtubule (MT) cytoskeletons, elucidating TF-mediated cytoskeletal regulatory programs is key to understanding molecular control of diverse dendritic morphologies. Previous studies in Drosophila melanogaster have demonstrated that the conserved TFs Cut and Knot exert combinatorial control over aspects of dendritic cytoskeleton development, promoting actin and MT-based arbor morphology, respectively. To investigate transcriptional targets of Cut and/or Knot regulation, we conducted systematic neurogenomic studies, coupled with in vivo genetic screens utilizing multi-fluor cytoskeletal and membrane marker reporters. These analyses identified a host of putative Cut and/or Knot effector molecules, and a subset of these putative TF targets converge on modulating dendritic cytoskeletal architecture, which are grouped into three major phenotypic categories, based upon neuromorphometric analyses: complexity enhancer, complexity shifter, and complexity suppressor. Complexity enhancer genes normally function to promote higher order dendritic growth and branching with variable effects on MT stabilization and F-actin organization, whereas complexity shifter and complexity suppressor genes normally function in regulating proximal-distal branching distribution or in restricting higher order branching complexity, respectively, with spatially restricted impacts on the dendritic cytoskeleton. Collectively, we implicate novel genes and cellular programs by which TFs distinctly and combinatorially govern dendritogenesis via cytoskeletal modulation.

Background: Osteoarthritis of the finger proximal interphalangeal joints (PIPJ's) is common and severely limits hand function. Intra-articular steroid injections are frequently used, but there is little research assessing this treatment option. Methods: This was a prospective audit of patients undergoing intra-articular steroid injections into the PIPJ under image intensifier guidance. The aims were to assess the duration of pain relief, hand function and range of movement following this procedure. Fifty injected joints were followed up at six weeks, three and six months. Results: There were significant improvements in both pain scores and the range of movement for up to three months. Analgesia requirements decreased and hand function improved up to three months. By six months, patients were approaching their preinjection scores. Conclusions: X-ray guided injections are a simple procedure which can be effectively performed in the out- patient setting, resulting in satisfied patients with improved hand function and pain scores.

Summary Microtubules (MTs) and F-actin (F-act) have long been recognized as key regulators of dendritic morphology. Nevertheless, precisely ascertaining their distinct influences on dendritic trees have been hampered until now by the lack of direct, arbor-wide cytoskeletal quantification. We pair live confocal imaging of fluorescently labeled dendritic arborization (da) neurons in Drosophila larvae with complete multi-signal neural tracing to separately measure MTs and F-act. We demonstrate that dendritic arbor length is highly interrelated with local MT quantity, whereas local F-act enrichment is associated with dendritic branching. Computational simulation of arbor structure solely constrained by experimentally observed subcellular distributions of these cytoskeletal components generated synthetic morphological and molecular patterns statistically equivalent to those of real da neurons, corroborating the efficacy of local MT and F-act in describing dendritic architecture. The analysis and modeling outcomes hold true for the simplest (class I), most complex (class IV), and genetically altered (Formin3 overexpression) da neuron types., Graphical Abstract, Highlights • Local microtubule quantity is highly interrelated with arbor length • Bifurcations are strongly associated with enrichment in local F-actin • A model based on local microtubule and F-actin reproduces dendritic morphology • The above findings are robust across cell types and genetic alterations, Biological Sciences; Molecular Biology; Neuroscience; Cell Biology