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In the presence of flavonoids, Rhizobium sp. strain NGR234 synthesizes a new lipopolysaccharide (LPS), characterized by a rhamnan O-antigen. The presence of this rhamnose-rich LPS is important for the establishment of competent symbiotic interactions between NGR234 and many species of leguminous plants. Two putative rhamnosyl transferases are encoded in a cluster of genes previously shown to be necessary for the synthesis of the rhamnose-rich LPS. These two genes, wbgA and rgpF, were mutated. The resulting mutant strains synthesized truncated rough LPS species rather than the wild-type rhamnose-rich LPS when grown with flavonoids. Based on the compositions of these purified mutant LPS species, we inferred that RgpF is responsible for adding the first one to three rhamnose residues to the flavonoid-induced LPS, whereas WbgA is necessary for the synthesis of the rest of the rhamnan O-antigen. The NGR234 homologue of lpsB, which, in other bacteria, encodes a glycosyl transferase acting early in synthesis of the core portion of LPS, was identified and also mutated. LpsB was required for all the LPS species produced by NGR234, in the presence or absence of flavonoids. Mutants (i.e., of lpsB and rgpF) that lacked any portion of the rhamnan O-antigen of the induced LPS were severely affected in their symbiotic interaction with Vigna unguiculata, whereas the NGRΩwbgA mutant, although having very few rhamnose residues in its LPS, was able to elicit functional nodules.

Cryovolcanism has been invoked to explain numerous features observed on icy bodies. Many of these features show similar morphologies to volcanic features observed on Earth suggesting similar physics involved in their formation. Cryovolcanism lies at the intersection of volcanology and hydrology but as such, no one model from either discipline satisfactorily represents cryolava flow emplacement. We produced a new model for cryolava flow evolution that draws from both disciplines to track the physical, chemical, and thermal states of a hypothetical H 2 O-NaCl flow on a Europa-like body as it evolves away from the vent. This model is currently restricted to compositions on the water-rich side of this chemical system and only predicts emplacement up to the turbulent to laminar transition. Modeling the laminar regime and a broader compositional space will be dealt with separately. Concentrations between 5 and 23 wt% (H 2 O-NaCl eutectic) and initial flow thicknesses of 0.1, 1, 10, and 100 m were set as initial conditions. Model results suggest that flow may reach 40-60 vol% solids before transitioning to laminar flow. The thermal budget for these flows is dominated by the heat loss from vaporization in the low-pressure environment. This model produces length to thickness aspect ratios, for the given compositions, that are broadly consistent with candidate cryovolcanic features on Ceres and Titan. These first-order comparisons are not ideal and suggest the need for future modeling of cryovolcanic features in at least two dimensions., (© 2022 The Authors.)

Sea urchins are premier model organisms for the study of early development. However, the lengthy generation times of commonly used species have precluded application of stable genetic approaches. Here, we use the painted sea urchin Lytechinus pictus to address this limitation and to generate a homozygous mutant sea urchin line. L. pictus has one of the shortest generation times of any currently used sea urchin. We leveraged this advantage to generate a knockout mutant of the sea urchin homolog of the drug transporter ABCB1, a major player in xenobiotic disposition for all animals. Using CRISPR/Cas9, we generated large fragment deletions of ABCB1 and used these readily detected deletions to rapidly genotype and breed mutant animals to homozygosity in the F2 generation. The knockout larvae are produced according to expected Mendelian distribution, exhibit reduced xenobiotic efflux activity and can be grown to maturity. This study represents a major step towards more sophisticated genetic manipulation of the sea urchin and the establishment of reproducible sea urchin animal resources., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)

Despite significant investigation of fly ash spills and mineralogical controls on the release of potentially toxic elements (PTEs) from fly ash, interactions with the surficial environment remain relatively poorly understood. We conducted 90-day batch leaching studies with paired analysis of supernatant and solid-phase mineralogy to assess the elemental release and transformation of fly ash upon reaction with aquatic media (18 MΩ cm -1 water and simulated rainwater). The fly ash in this study, collected from the University of Alaska Fairbanks stoker-boiler power plant, is high in unburned carbon (~20% LOI) and highly enriched in several PTEs relative to the upper continental crust. Supernatant concentrations of oxyanion-forming elements (e.g., As, Se, Mo, Sb) remained relatively low and constant, suggesting equilibrium with the solid phase, possibly ettringite [Ca 6 Al 2 (SO 4 ) 3 (OH) 12 •26H 2 O], which is known to incorporate and sorb oxyanion-forming PTEs and was identified by X-ray diffraction. Synthetic precipitation leaching procedure (SPLP) results failed to capture important temporal trends. Lead and Ba supernatant concentrations consistently exceeded drinking water standards, as well as others upon exposure to simulated physiological solutions. Seven-day experiments with dissolved organic matter-isolate solutions indicated that for certain elements, liberation was influenced by carbon concentration and/or the identity of the isolate. Overall, this paired approach can serve as a model for future studies, bridging existing gaps between batch leaching and single-element mineralogical, sorption, or speciation studies., (© 2021. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Objective: This study examined the effects of a short-term reduction in physical activity, and subsequent resumption, on metabolic profiles, body composition and cardiovascular (endothelial) function., Design: Twenty-eight habitually active (≥10,000 steps/day) participants (18 female, 10 male; age 32 ± 11 years; BMI 24.3 ± 2.5 kg/m 2 ) were assessed at baseline, following 14 days of step-reduction and 14 days after resuming habitual activity., Methods: Physical activity was monitored throughout (SenseWear Armband). Endothelial function (flow mediated dilation; FMD), cardiorespiratory fitness ( V . ⁢ O 2 peak) and body composition including liver fat (dual-energy x-ray absorptiometry and magnetic resonance spectroscopy) were determined at each assessment. Statistical analysis was performed using one-way within subject's ANOVA; data presented as mean (95% CI)., Results: Participants decreased their step count from baseline by 10,111 steps/day (8949, 11,274; P < 0.001), increasing sedentary time by 103 min/day (29, 177; P < 0.001). Following 14 days of step-reduction, endothelial function was reduced by a 1.8% (0.4, 3.3; P = 0.01) decrease in FMD. Following resumption of habitual activity, FMD increased by 1.4%, comparable to the baseline level 0.4% (-1.8, 2.6; P = 1.00). Total body fat, waist circumference, liver fat, whole body insulin sensitivity and cardiorespiratory fitness were all adversely affected by 14 days step-reduction ( P < 0.05) but returned to baseline levels following resumption of activity., Conclusion: This data shows for the first time that whilst a decline in endothelial function is observed following short-term physical inactivity, this is reversed on resumption of habitual activity. The findings highlight the need for public health interventions that focus on minimizing time spent in sedentary behavior., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Bowden Davies, Norman, Thompson, Mitchell, Harrold, Halford, Wilding, Kemp, Cuthbertson and Sprung.)

Axon injury is a hallmark of many neurodegenerative diseases, often resulting in neuronal cell death and functional impairment. Dual leucine zipper kinase (DLK) has emerged as a key mediator of this process. However, while DLK inhibition is robustly protective in a wide range of neurodegenerative disease models, it also inhibits axonal regeneration. Indeed, there are no genetic perturbations that are known to both improve long-term survival and promote regeneration. To identify such a neuroprotective target, we conducted a set of complementary high-throughput screens using a protein kinase inhibitor library in human stem cell-derived retinal ganglion cells (hRGCs). Overlapping compounds that promoted both neuroprotection and neurite outgrowth were bioinformatically deconvoluted to identify specific kinases that regulated neuronal death and axon regeneration. This work identified the role of germinal cell kinase four (GCK-IV) kinases in cell death and additionally revealed their unexpected activity in suppressing axon regeneration. Using an adeno-associated virus (AAV) approach, coupled with genome editing, we validated that GCK-IV kinase knockout improves neuronal survival, comparable to that of DLK knockout, while simultaneously promoting axon regeneration. Finally, we also found that GCK-IV kinase inhibition also prevented the attrition of RGCs in developing retinal organoid cultures without compromising axon outgrowth, addressing a major issue in the field of stem cell-derived retinas. Together, these results demonstrate a role for the GCK-IV kinases in dissociating the cell death and axonal outgrowth in neurons and their druggability provides for therapeutic options for neurodegenerative diseases., Competing Interests: The authors declare no competing interest., (Copyright © 2020 the Author(s). Published by PNAS.)

Background: Data suggest that metabolic health status, incorporating components of metabolic syndrome (MetS), predicts cardiovascular disease (CVD) risk better than BMI. This study explored the association of MetS and obesity with endothelial function, a prognostic risk factor for incident CVD., Methods: Forty-four participants were phenotyped according to BMI as non-obese vs obese (<30 or >30 kg/m2) and according to the International Diabetes Federation criteria of MetS: ≤2 criteria MetS (MetS-) vs ≥3 criteria MetS (MetS+); (1.)non-obese MetS- vs (2.) non-obese MetS+ and (3.) obese MetS- vs (4.) obese MetS+. Flow-mediated dilation (FMD), body composition including liver fat (MRI and spectroscopy), dietary intake, intensities of habitual physical activity and cardio-respiratory fitness were determined. Variables were analysed using a one-factor between-groups ANOVA and linear regression; mean (95% CI) are presented., Results: Individuals with MetS+ displayed lower FMD than those with MetS-. For non-obese individuals mean difference between MetS+ and MetS- was 4.1% ((1.0, 7.3); P = 0.004) and obese individuals had a mean difference between MetS+ and MetS- of 6.2% ((3.1, 9.2); P < 0.001). Although there was no association between BMI and FMD (P = 0.27), an increased number of MetS components was associated with a lower FMD (P = 0.005), and after adjustment for age and sex, 19.7% of the variance of FMD was explained by MetS, whereas only 1.1% was explained by BMI., Conclusions: In this study cohort, components of MetS, rather than obesity per se, contribute to reduced FMD, which suggests a reduced bioavailability of nitric oxide and thus increased risk of CVD.

Estimates of chronic conditions and disability among individuals on community supervision in the United States are lacking. We used 2015-2016 data from the National Survey on Drug Use and Health ( N = 78,761) to examine the prevalence of chronic conditions and disability among nonelderly adults who had been on probation or parole in the past year, compared to adults without community supervision in the past year. The weighted sample was representative of 4,594,412 adults on community supervision and 191,156,710 adults without community supervision in the past year. Compared to the general population, adults recently on community supervision were significantly more likely to report fair or poor health, chronic obstructive pulmonary disease, hepatitis B or C, one or more chronic conditions, and any disability. Collaboration between health and criminal justice systems is needed to accommodate the health needs and supervision requirements for individuals with community supervision.

Introduction/purpose: To investigate whether (a) lower levels of daily physical activity (PA) and greater sedentary time accounted for contrasting metabolic phenotypes (higher liver fat/presence of metabolic syndrome [METS+] vs lower liver fat/absence of metabolic syndrome [METS-]) in individuals of similar body mass index and (b) the association of sedentary time on metabolic health and liver fat., Methods: Ninety-eight habitually active participants (53 female, 45 male; age, 39 ± 13 yr; body mass index 26.9 ± 5.1 kg·m), underwent assessments of PA (SenseWear armband; wear time ~98%), cardiorespiratory fitness (V˙O2 peak), body composition (magnetic resonance imaging and magnetic resonance spectroscopy) and multiorgan insulin sensitivity (oral glucose tolerance test). We undertook a) cross-sectional analysis comparing four groups: nonobese or obese, with and without metabolic syndrome (METS+ vs METS-) and b) univariate and multivariate regression for sedentary time and other levels of PA in relation to liver fat., Results: Light, moderate, and vigorous PA did not account for differences in metabolic health between individuals, whether nonobese or obese, although METS+ individuals were more sedentary, with a higher number, and prolonged bouts (~1-2 h). Overall, sedentary time, average daily METS and V˙O2 peak were each independently associated with liver fat percentage. Each additional hour of daily sedentary time was associated with a 1.15% (95% confidence interval, 1.14%-1.50%) higher liver fat content., Conclusions: Greater sedentary time, independent of other levels of PA, is associated with being metabolically unhealthy; even in habitually active people, lesser sedentary time, and higher cardiorespiratory fitness and average daily METS is associated with lower liver fat.

Ice sintering is a form of metamorphism that drives the microstructural evolution of an aggregate of grains through surface and volume diffusion. This leads to an increase in the grain-to-grain contact area ("neck") and density of the aggregate over time, resulting in the evolution of its strength, porosity, thermal conductivity, and other properties. This process plays an important role in the evolution of icy planetary surfaces, though its rate and nature are not well constrained. In this study, we explore the model of Swinkels and Ashby (1981), and assess the extent to which it can be used to quantify sintering timescales for water ice. We compare predicted neck growth rates to new and historical observations of ice sintering, and find agreement to some studies at the order of magnitude level. First-order estimates of neck growth timescales on planetary surfaces show that ice may undergo significant modification over geologic timescales, even in the outer solar system. Densification occurs over much longer timescales, suggesting some surfaces may develop cohesive, but porous, crusts. Sintering rates are extremely sensitive to temperature and grain size, occurring faster in warmer aggregates of smaller grains. This suggests that the microstructural evolution of ices may vary not only throughout the solar system, but also spatially across the surface and in the near-surface of a given body. Our experimental observations of complex grain growth and mass redistribution in ice aggregates point to components of the model that may benefit from improvement, and areas where additional laboratory studies are needed.

Aims/hypothesis: Low physical activity levels and sedentary behaviour are associated with obesity, insulin resistance and type 2 diabetes. We investigated the effects of a short-term reduction in physical activity with increased sedentary behaviour on metabolic profiles and body composition, comparing the effects in individuals with first-degree relatives with type 2 diabetes (FDR+ve) vs those without (FDR-ve)., Methods: Forty-five habitually active participants (16 FDR+ve [10 female, 6 male] and 29 FDR-ve [18 female, 11 male]; age 36 ± 14 years) were assessed at baseline, after 14 days of step reduction and 14 days after resuming normal activity. We determined physical activity (using a SenseWear armband), cardiorespiratory fitness ([Formula: see text]), body composition (dual-energy x-ray absorptiometry/magnetic resonance spectroscopy) and multi-organ insulin sensitivity (OGTT) at each time point. Statistical analysis was performed using a two-factor between-groups ANCOVA, with data presented as mean ± SD or (95% CI)., Results: There were no significant between-group differences in physical activity either at baseline or following step reduction. During the step-reduction phase, average daily step count decreased by 10,285 steps (95% CI 9389, 11,182; p < 0.001), a reduction of 81 ± 8%, increasing sedentary time by 223 min/day (151, 295; p < 0.001). Pooling data from both groups, following step reduction there was a significant decrease in whole-body insulin sensitivity (Matsuda index) (p < 0.001), muscle insulin sensitivity index (p < 0.001), cardiorespiratory fitness (p = 0.002) and lower limb lean mass (p = 0.004). Further, there was a significant increase in total body fat (p < 0.001), liver fat (p = 0.001) and LDL-cholesterol (p = 0.013), with a borderline significant increase in NEFA AUC during the OGTT (p = 0.050). Four significant between-group differences were apparent: following step reduction, FDR+ve participants accumulated 1.5% more android fat (0.4, 2.6; p = 0.008) and increased triacylglycerol by 0.3 mmol/l (0.1, 0.6; p = 0.044). After resuming normal activity, FDR+ve participants engaged in lower amounts of vigorous activity (p = 0.006) and had lower muscle insulin sensitivity (p = 0.023). All other changes were reversed with no significant between-group differences., Conclusions/interpretation: A short-term reduction in physical activity with increased sedentary behaviour leads to a reversible reduction in multi-organ insulin sensitivity and cardiorespiratory fitness, with concomitant increases in central and liver fat and dyslipidaemia. The effects are broadly similar in FDR+ve and FDR-ve individuals. Public health recommendations promoting physical activity should incorporate advice to avoid periods of sedentary behaviour.

Optic neuropathies such as glaucoma are characterized by the degeneration of retinal ganglion cells (RGCs) and the irreversible loss of vision. In these diseases, focal axon injury triggers a propagating axon degeneration and, eventually, cell death. Previous work by us and others identified dual leucine zipper kinase (DLK) and JUN N-terminal kinase (JNK) as key mediators of somal cell death signaling in RGCs following axonal injury. Moreover, others have shown that activation of the DLK/JNK pathway contributes to distal axonal degeneration in some neuronal subtypes and that this activation is dependent on the adaptor protein, sterile alpha and TIR motif containing 1 (SARM1). Given that SARM1 acts upstream of DLK/JNK signaling in axon degeneration, we tested whether SARM1 plays a similar role in RGC somal apoptosis in response to optic nerve injury. Using the mouse optic nerve crush (ONC) model, our results show that SARM1 is critical for RGC axonal degeneration and that axons rescued by SARM1 deficiency are electrophysiologically active. Genetic deletion of SARM1 did not, however, prevent DLK/JNK pathway activation in RGC somas nor did it prevent or delay RGC cell death. These results highlight the importance of SARM1 in RGC axon degeneration and suggest that somal activation of the DLK/JNK pathway is activated by an as-yet-unidentified SARM1-independent signal., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Human pluripotent stem cells have the potential to promote biological studies and accelerate drug discovery efforts by making possible direct experimentation on a variety of human cell types of interest. However, stem cell cultures are generally heterogeneous and efficient differentiation and purification protocols are often lacking. Here, we describe the generation of clustered regularly-interspaced short palindromic repeats(CRISPR)-Cas9 engineered reporter knock-in embryonic stem cell lines in which tdTomato and a unique cell-surface protein, THY1.2, are expressed under the control of the retinal ganglion cell (RGC)-enriched gene BRN3B. Using these reporter cell lines, we greatly improved adherent stem cell differentiation to the RGC lineage by optimizing a novel combination of small molecules and established an anti-THY1.2-based protocol that allows for large-scale RGC immunopurification. RNA-sequencing confirmed the similarity of the stem cell-derived RGCs to their endogenous human counterparts. Additionally, we developed an in vitro axonal injury model suitable for studying signaling pathways and mechanisms of human RGC cell death and for high-throughput screening for neuroprotective compounds. Using this system in combination with RNAi-based knockdown, we show that knockdown of dual leucine kinase (DLK) promotes survival of human RGCs, expanding to the human system prior reports that DLK inhibition is neuroprotective for murine RGCs. These improvements will facilitate the development and use of large-scale experimental paradigms that require numbers of pure RGCs that were not previously obtainable. Stem Cells Translational Medicine 2017;6:1972-1986., (© 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.)

Health care providers are in the unique position to promote a healthy postdeployment transition by assisting veterans to recognize nonpathologic transition symptoms, select appropriate coping strategies, and seek further assistance for more complex problems., Competing Interests: Author disclosures The author reports no actual or potential conflicts of interest with regard to this article.

Dual leucine zipper kinase (DLK) has been implicated in cell death signaling secondary to axonal damage in retinal ganglion cells (RGCs) and other neurons. To better understand the pathway through which DLK acts, we developed enhanced functional genomic screens in primary RGCs, including use of arrayed, whole-genome, small interfering RNA libraries. Explaining why DLK inhibition is only partially protective, we identify leucine zipper kinase (LZK) as cooperating with DLK to activate downstream signaling and cell death in RGCs, including in a mouse model of optic nerve injury, and show that the same pathway is active in human stem cell-derived RGCs. Moreover, we identify four transcription factors, JUN, activating transcription factor 2 (ATF2), myocyte-specific enhancer factor 2A (MEF2A), and SRY-Box 11 (SOX11), as being the major downstream mediators through which DLK/LZK activation leads to RGC cell death. Increased understanding of the DLK pathway has implications for understanding and treating neurodegenerative diseases., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Delayed revascularization of ischemic neural tissue is a major impediment to preservation of function in central nervous system (CNS) diseases including stroke and ischemic retinopathies. Therapeutic strategies allowing rapid revascularization are greatly needed to reduce ischemia-induced cellular damage and suppress harmful pathologic neovascularization. However, key mechanisms governing vascular recovery in ischemic CNS, including regulatory molecules governing the transition from tissue injury to tissue repair, are largely unknown. NF-E2-related factor 2 (Nrf2) is a major stress-response transcription factor well known for its cell-intrinsic cytoprotective function. However, its role in cell-cell crosstalk is less appreciated. Here we report that Nrf2 is highly activated in ischemic retina and promotes revascularization by modulating neurons in their paracrine regulation of endothelial cells. Global Nrf2 deficiency strongly suppresses retinal revascularization and increases pathologic neovascularization in a mouse model of ischemic retinopathy. Conditional knockout studies demonstrate a major role for neuronal Nrf2 in vascular regrowth into avascular retina. Deletion of neuronal Nrf2 results in semaphorin 6A (Sema6A) induction in hypoxic/ischemic retinal ganglion cells in a hypoxia-inducible factor-1 alpha (HIF-1α)-dependent fashion. Sema6A expression increases in avascular inner retina and colocalizes with Nrf2 in human fetal eyes. Extracellular Sema6A leads to dose-dependent suppression of the migratory phenotype of endothelial cells through activation of Notch signaling. Lentiviral-mediated delivery of Sema6A small hairpin RNA (shRNA) abrogates the defective retinal revascularization in Nrf2-deficient mice. Importantly, pharmacologic Nrf2 activation promotes reparative angiogenesis and suppresses pathologic neovascularization. Our findings reveal a unique function of Nrf2 in reprogramming ischemic tissue toward neurovascular repair via Sema6A regulation, providing a potential therapeutic strategy for ischemic retinal and CNS diseases.

Purpose: To determine if oral losartan treatment decreases the retinal ganglion cell (RGC) death caused by experimental intraocular pressure (IOP) elevation in mice., Methods: We produced IOP increase in CD1 mice and performed unilateral optic nerve crush. Mice received oral losartan, spironolactone, enalapril, or no drug to test effects of inhibiting angiotensin receptors. IOP was monitored by Tonolab, and blood pressure was monitored by tail cuff device. RGC loss was measured in masked axon counts and RGC bodies by β-tubulin labeling. Scleral changes that could modulate RGC injury were measured including axial length, scleral thickness, and retinal layer thicknesses, pressure-strain behavior in inflation testing, and study of angiotensin receptors and pathways by reverse transcription polymerase chain reaction, Western blot, and immunohistochemistry., Results: Losartan treatment prevented significant RGC loss (median loss = 2.5%, p = 0.13), while median loss with water, spironolactone, and enalapril treatments were 26%, 28% and 43%; p < 0.0001). The lower RGC loss with losartan was significantly less than the loss with spironolactone or enalapril (regression model p = 0.001; drug treatment group term p = 0.01). Both losartan and enalapril significantly lowered blood pressure (p< 0.001), but losartan was protective, while enalapril led to worse than water-treated RGC loss. RGC loss after crush injury was unaffected by losartan treatment (difference from control p = 0.9). Survival of RGC in cell culture was not prolonged by sartan treatment. Axonal transport blockade after 3 day IOP elevations was less in losartan-treated than in control glaucoma eyes (p = 0.007). Losartan inhibited effects of glaucoma, including reduction in extracellular signal-related kinase activity and modification of glaucoma-related changes in scleral thickness and creep under controlled IOP., Conclusions: The neuroprotective effect of losartan in mouse glaucoma is associated with adaptive changes in the sclera expressed at the optic nerve head.

Retinal ischemia plays a critical role in multiple vision-threatening diseases and leads to death of retinal neurons, particularly ganglion cells. Oxidative stress plays an important role in this ganglion cell loss. Nrf2 (NF-E2-related factor 2) is a major regulator of the antioxidant response, and its role in the retina is increasingly appreciated. We investigated the potential retinal neuroprotective function of Nrf2 after ischemia-reperfusion (I/R) injury. In an experimental model of retinal I/R, Nrf2 knockout mice exhibited much greater loss of neuronal cells in the ganglion cell layer than wild-type mice. Primary retinal ganglion cells isolated from Nrf2 knockout mice exhibited decreased cell viability compared to wild-type retinal ganglion cells, demonstrating the cell-intrinsic protective role of Nrf2. The retinal neuronal cell line 661W exhibited reduced cell viability following siRNA-mediated knockdown of Nrf2 under conditions of oxidative stress, and this was associated with exacerbation of increase in reactive oxygen species. The synthetic triterpenoid CDDO-Im (2-Cyano-3,12-dioxooleana-1,9-dien-28-imidazolide), a potent Nrf2 activator, inhibited reactive oxygen species increase in cultured 661W under oxidative stress conditions and increased neuronal cell survival after I/R injury in wild-type, but not Nrf2 knockout mice. Our findings indicate that Nrf2 exhibits a retinal neuroprotective function in I/R and suggest that pharmacologic activation of Nrf2 could be a therapeutic strategy. Oxidative stress is thought to be an important mediator of retinal ganglion cell death in ischemia-reperfusion injury. We found that the transcription factor NF-E2-related factor 2 (Nrf2), a major regulator of oxidative stress, is an important endogenous neuroprotective molecule in retinal ganglion cells in ischemia-reperfusion, exerting a cell-autonomous protective effect.  The triterpenoid 2-Cyano-3,12-dioxooleana-1,9-dien-28-imidazolide (CDDO-Im) reduces neurodegeneration following ischemia-reperfusion in an Nrf2-dependent fashion. This suggests that Nrf2-activating drugs including triterpenoids could be a therapeutic strategy for retinal neuroprotection., (© 2015 International Society for Neurochemistry.)

Introduction: The cystic fibrosis-related diabetes (CFRD) guidelines produced by the UK CF Trust differ from those used in Europe and the US. We conducted a study to establish current practice., Method: Paediatric and adult questionnaires were devised and emailed to the 48 specialist UK CF centres., Results: Completed questionnaires were returned by 39/48 (81%) centres. Only 3/21 (14%) paediatric centres begin annual screening at 12 years (as per UK guidelines), 11/21 (52%) start to screen at 10 years (as per European and US guidelines) and 5/21 (24%) begin screening at a child's first annual review. The oral glucose tolerance test is used as a screening test in 33/39 (85%) of centres but only 3/33 (9%) use it in isolation. Home glucose monitoring is the most frequently used diagnostic test undertaken in 32/39 (82%) centres, and again this is rarely used in isolation. The decision to initiate insulin is often shared between specialist nurses and doctors., Conclusions: In the UK the majority of CF centres use the OGTT to screen and HGM to diagnose CFRD. The use of other tools varies with poor adherence to UK guidelines. These 2004 guidelines would benefit from being updated to reflect current best evidence., (Copyright © 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

The origin of the turtle shell over 200 million years ago greatly modified the amniote body plan, and the morphological plasticity of the shell has promoted the adaptive radiation of turtles. The shell, comprising a dorsal carapace and a ventral plastron, is a layered structure formed by basal endochondral axial skeletal elements (ribs, vertebrae) and plates of bone, which are overlain by keratinous ectodermal scutes. Studies of turtle development have mostly focused on the bones of the shell; however, the genetic regulation of the epidermal scutes has not been investigated. Here, we show that scutes develop from an array of patterned placodes and that these placodes are absent from a soft-shelled turtle in which scutes were lost secondarily. Experimentally inhibiting Shh, Bmp or Fgf signaling results in the disruption of the placodal pattern. Finally, a computational model is used to show how two coupled reaction-diffusion systems reproduce both natural and abnormal variation in turtle scutes. Taken together, these placodal signaling centers are likely to represent developmental modules that are responsible for the evolution of scutes in turtles, and the regulation of these centers has allowed for the diversification of the turtle shell., (© 2014. Published by The Company of Biologists Ltd.)

Foxes (n = 499), shot during vertebrate pest control programs, were collected in various sites in the Australian Capital Territory (ACT), New South Wales (NSW) and Western Australia (WA). Wild dogs (dingoes (Canis lupus dingo) and their hybrids with domestic dogs) (n = 52) captured also as part of vertebrate pest control programs were collected from several sites in the ACT and NSW. The intestine from each fox and wild dog was collected, and all Taenia tapeworms identified morphologically were collected and identified to species based on the DNA sequence of the small subunit of the mitochondrial ribosomal RNA (rrnS) gene. Taenia species were recovered from 6.0% of the ACT/NSW foxes, 5.1% of WA foxes and 46.1% of ACT/NSW wild dogs. Taenia ovis was recovered from two foxes, 1/80 from Jugiong, NSW and 1/102 from Katanning, WA. We confirm from rrnS sequences the presence of T. ovis in cysts from hearts and diaphragms and T aenia hydatigena in cysts from livers of sheep in Australia. T. ovis was not recovered from any of the wild dogs examined but T. hydatigena were recovered from 4(8.3%) wild dogs and a single fox. With foxes identified as a definitive host for T. ovis in Australia, new control strategies to stop transmission of T. ovis to sheep need to be adopted.

Glaucoma, a major cause of blindness worldwide, is a neurodegenerative optic neuropathy in which vision loss is caused by loss of retinal ganglion cells (RGCs). To better define the pathways mediating RGC death and identify targets for the development of neuroprotective drugs, we developed a high-throughput RNA interference screen with primary RGCs and used it to screen the full mouse kinome. The screen identified dual leucine zipper kinase (DLK) as a key neuroprotective target in RGCs. In cultured RGCs, DLK signaling is both necessary and sufficient for cell death. DLK undergoes robust posttranscriptional up-regulation in response to axonal injury in vitro and in vivo. Using a conditional knockout approach, we confirmed that DLK is required for RGC JNK activation and cell death in a rodent model of optic neuropathy. In addition, tozasertib, a small molecule protein kinase inhibitor with activity against DLK, protects RGCs from cell death in rodent glaucoma and traumatic optic neuropathy models. Together, our results establish a previously undescribed drug/drug target combination in glaucoma, identify an early marker of RGC injury, and provide a starting point for the development of more specific neuroprotective DLK inhibitors for the treatment of glaucoma, nonglaucomatous forms of optic neuropathy, and perhaps other CNS neurodegenerations.

Objective: The recent recognition of the correlation of the hip-knee-ankle angle (HKA) with femur-tibia angle (FTA) on a standard knee radiograph has led to the increasing inclusion of FTA assessments in OA studies due to its clinical relevance, cost effectiveness and minimal radiation exposure. Our goal was to investigate the performance metrics of currently used methods of FTA measurement to determine whether a specific protocol could be recommended based on these results., Methods: Inter- and intra-rater reliability of FTA measurements were determined by intraclass correlation coefficient (ICC) of two independent analysts. Minimal detectable differences were determined and the correlation of FTA and HKA was analyzed by linear regression. Differences among methods of measuring HKA were assessed by ANOVA., Results: All five methods of FTA measurement demonstrated high precision by inter- and intra-rater reproducibility (ICCs>or=0.93). All five methods displayed good accuracy, but after correction for the offset of FTA from HKA, the femoral notch landmark method was the least accurate. However, the methods differed according to their minimal detectable differences; the FTA methods utilizing the center of the base of the tibial spines or the center of the tibial plateau as knee center landmarks yielded the smallest minimal detectable differences (1.25 degrees and 1.72 degrees, respectively)., Conclusion: All methods of FTA were highly reproducible, but varied in their accuracy and sensitivity to detect meaningful differences. Based on these parameters we recommend standardizing measurement angles with vertices at the base of the tibial spines or the center of the tibia and comparing single-point and two-point methods in larger studies., (Copyright 2009 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

The surface of Saturn's haze-shrouded moon Titan has long been proposed to have oceans or lakes, on the basis of the stability of liquid methane at the surface. Initial visible and radar imaging failed to find any evidence of an ocean, although abundant evidence was found that flowing liquids have existed on the surface. Here we provide definitive evidence for the presence of lakes on the surface of Titan, obtained during the Cassini Radar flyby of Titan on 22 July 2006 (T16). The radar imaging polewards of 70 degrees north shows more than 75 circular to irregular radar-dark patches, in a region where liquid methane and ethane are expected to be abundant and stable on the surface. The radar-dark patches are interpreted as lakes on the basis of their very low radar reflectivity and morphological similarities to lakes, including associated channels and location in topographic depressions. Some of the lakes do not completely fill the depressions in which they lie, and apparently dry depressions are present. We interpret this to indicate that lakes are present in a number of states, including partly dry and liquid-filled. These northern-hemisphere lakes constitute the strongest evidence yet that a condensable-liquid hydrological cycle is active in Titan's surface and atmosphere, in which the lakes are filled through rainfall and/or intersection with the subsurface 'liquid methane' table.

Background & Aims: Patients with Barrett's esophagus (BE) have a risk of esophageal adenocarcinoma of approximately 0.5% per year. Patients may have difficulty understanding this risk. This study assessed the perceived risk of cancer in patients with BE, and correlated their risk estimates with their health care use behaviors., Methods: We performed a survey of patients with BE participating in an endoscopic surveillance program at 2 sites: a university teaching hospital and a Veterans' Administration hospital. A questionnaire also elicited their demographics as well as their sources of health information. Health care behaviors, including physician visits and endoscopic surveillance behaviors, were assessed. Patients were classified as either overestimators or nonoverestimators of risk. Characteristics of overestimators, as well as health care use patterns, were assessed., Results: One hundred eighteen patients met entry criteria, and 92 (78%) completed all the questionnaires. Sixty-eight percent of patients overestimated their 1-year risk of cancer, with a mean estimated 1-year cancer risk being 13.6%. The lifetime risk also was overestimated by 38% of patients. Patients who overestimated risk were more likely to be Veterans' Administration medical center patients, have more symptomatic reflux, and were more likely to use the Internet to get health care information. There was no significant difference in physician visits between overestimators and nonestimators (1.2 visits per year vs 1.0, P = .20), nor in endoscopy use (5.7 endoscopies per 5-year period vs 5.0, P = .42)., Conclusions: The majority of patients with prevalent BE participating in an endoscopic surveillance program overestimated their chances of developing adenocarcinoma of the esophagus. Efforts to improve education of such patients with BE are warranted.

The majority of volcanic products on Mars are thought to be mafic and effusive. Explosive eruptions of basic to ultrabasic chemistry are expected to be common, but evidence for them is rare and mostly confined to very old surface features. Here we present new image and topographic data from the High Resolution Stereo Camera that reveal previously unknown traces of an explosive eruption at 30 degrees N and 149 degrees E on the northwestern flank of the shield volcano Hecates Tholus. The eruption created a large, 10-km-diameter caldera approximately 350 million years ago. We interpret these observations to mean that large-scale explosive volcanism on Mars was not confined to the planet's early evolution. We also show that glacial deposits partly fill the caldera and an adjacent depression. Their age, derived from crater counts, is about 5 to 24 million years. Climate models predict that near-surface ice is not stable at mid-latitudes today, assuming a thermo-dynamic steady state. Therefore, the discovery of very young glacial features at Hecates Tholus suggests recent climate changes. We show that the absolute ages of these very recent glacial deposits correspond very well to a period of increased obliquity of the planet's rotational axis.

It is thought that the Cerberus Fossae fissures on Mars were the source of both lava and water floods two to ten million years ago. Evidence for the resulting lava plains has been identified in eastern Elysium, but seas and lakes from these fissures and previous water flooding events were presumed to have evaporated and sublimed away. Here we present High Resolution Stereo Camera images from the European Space Agency Mars Express spacecraft that indicate that such lakes may still exist. We infer that the evidence is consistent with a frozen body of water, with surface pack-ice, around 5 degrees north latitude and 150 degrees east longitude in southern Elysium. The frozen lake measures about 800 x 900 km in lateral extent and may be up to 45 metres deep--similar in size and depth to the North Sea. From crater counts, we determined its age to be 5 +/- 2 million years old. If our interpretation is confirmed, this is a place that might preserve evidence of primitive life, if it has ever developed on Mars.

Elective esophageal variceal ligation (EVL) is performed to decrease the risk of variceal hemorrhage. Side effects of EVL include hemorrhage, chest pain, dysphagia, and odynophagia. Because gastric acid may exacerbate postbanding ulcers and delay healing, proton pump inhibition may decrease side effects associated with EVL. The aim of this study was to assess the efficacy of pantoprazole, a proton pump inhibitor, as an adjunct to elective EVL. We performed a double-blinded, randomized, placebo-controlled trial of pantoprazole after elective EVL. Subjects in the pantoprazole arm received 40 mg pantoprazole intravenously after EVL followed by 40 mg oral pantoprazole for 9 days. Control subjects received intravenous and oral placebo. Subjects underwent upper endoscopy 10 to 14 days after banding. Primary outcomes included the size and number of ulcers and the subjects' reports of dysphagia, chest pain, and heartburn. Forty-four subjects were randomized: 42 completed the protocol. At follow-up endoscopy, the mean number of ulcers was similar in the two groups. However, the ulcers in the pantoprazole group were on average half as large as in the placebo group (37 mm(2) vs. 82 mm(2), P < .01). Chest pain, dysphagia, and heartburn scores were not significantly different. Four subjects, all in the placebo group, had adverse outcomes, including 3 who bled from postbanding ulcers and 1 with sepsis. In conclusion, subjects receiving pantoprazole after elective EVL had significantly smaller postbanding ulcers on follow-up endoscopy than subjects receiving placebo. However, the total ulcer number and patient symptoms were not different between the groups.

Background: Barrett's esophagus (BE) is associated with an increased risk of adenocarcinoma of the esophagus. Despite this increased risk, most cohort studies demonstrate that the mean life expectancy of subjects with BE is no different than age-matched controls. The indirect costs associated with a diagnosis of BE are unclear., Aim: To assess the effect of a diagnosis of BE on insurance premiums., Methods: We assessed twenty national life insurance companies (10 in southern California, 10 in North Carolina) to determine the effect of a diagnosis of BE on life insurance premiums. Our base case in Los Angeles was a 36-yr-old female nonsmoker, and in North Carolina, a 43-yr-old Caucasian male nonsmoker, both in excellent health except for a diagnosis of prevalent BE with no dysplasia. The policy requested was a 20-yr guaranteed term life insurance in the amount of $1,000,000. Companies were asked for their best price exclusive of the BE, and also their best price when considering BE as a preexisting condition. For those companies not offering the "preferred" rates, the insurance representative was subsequently sent a physician's letter explaining BE and providing data substantiating a normal life expectancy in the condition. Companies were also asked for health insurance quotes, including premiums and deductibles, inclusive and exclusive of the diagnosis of BE., Results: Twenty national insurance companies were contacted. For the 43-yr-old man with no BE, the yearly "preferred" premium for life insurance averaged $1,255. The mean cost of the policies offered to the same individual with BE as a preexisting condition was $2,731 (p < 0.001). For the 36-yr-old female the base rate exclusive of BE was $517, with a range of $472-$551. After inclusion of the diagnosis of BE, the mean rate rose by 177%, to $1,434, with a range of $1,144-$1,896. Companies either refused to provide health insurance to the individual with BE or would not provide a quote without review of the medical record. None of the insurance companies changed their quoted rates after receiving the letter written by the physician on behalf of the individual., Conclusions: Despite the preponderance of data demonstrating a normal life expectancy associated with the condition, a diagnosis of BE more than doubles life insurance premiums, and impacts the availability of health insurance. Further steps to educate insurance companies about the risks associated with BE are warranted, and patients should understand this additional "risk" of endoscopic screening for BE. There are significant indirect costs associated with a diagnosis of BE.