Interaction between acrylic substrates and RAD16-I peptide in its self-assembling

[EN] Self-assembling peptides (SAP) are widely used as scaffolds themselves, and recently as fillers of microporous scaffolds, where the former provides a cell-friendly nanoenvironment and the latter improves its mechanical properties. The characterization of the interaction between these short peptides and the scaffold material is crucial to assess the potential of such a combined system. In this work, the interaction between poly(ethyl acrylate) (PEA) and 90/10 ethyl acrylate-acrylic acid copolymer P(EAcoAAc) with the SAP RAD16-I has been followed using a bidimensional simplified model. By means of the techniques of choice (congo red staining, atomic force microscopy (AFM), and contact angle measurements) the interaction and self-assembly of the peptide has proven to be very sensitive to the wettability and electro-negativity of the polymeric substrate.The authors acknowledge funding through the European Commission FP7 project RECATABI (NMP3-SL-2009-229239), and from the Spanish Ministerio de Ciencia e Innovacion through projects MAT2011-28791-C03-02 and -03. This work was also supported by the Spanish Ministerio de Educacion through M. Arnal-Pastor FPU 2009-1870 grant. The authors acknowledge the assistance and advice of Electron Microscopy Service of the UPV.Arnal Pastor, MP.; González-Mora, D.; García-Torres, F.; Monleón Pradas, M.; Vallés Lluch, A. (2016). Interaction between acrylic substrates and RAD16-I peptide in its self-assembling. 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Transverse Plane Tendon and Median Nerve Motion in the Carpal Tunnel: Ultrasound Comparison of Carpal Tunnel Syndrome Patients and Healthy Volunteers

The median nerve and flexor tendons are known to translate transversely in the carpal tunnel. The purpose of this study was to investigate these motions in differential finger motion using ultrasound, and to compare them in healthy people and carpal tunnel syndrome patients.Transverse ultrasounds clips were taken during fist, index finger, middle finger and thumb flexion in 29 healthy normal subjects and 29 CTS patients. Displacement in palmar-dorsal and radial-ulnar direction was calculated using Analyze software. Additionally, the distance between the median nerve and the tendons was calculated.We found a changed motion pattern of the median nerve in middle finger, index finger and thumb motion between normal subjects and CTS patients (p<0.05). Also, we found a changed motion direction in CTS patients of the FDS III tendon in fist and middle finger motion, and of the FDS II and flexor pollicis longus tendon in index finger and thumb motion, respectively (p<0.05). The distance between the median nerve and the FDS II or FPL tendon is significantly greater in patients than in healthy volunteers for index finger and thumb motion, respectively (p<0.05).Our results suggest a changed motion pattern of the median nerve and several tendons in carpal tunnel syndrome patients compared to normal subjects. Such motion patterns may be useful in distinguishing affected from unaffected individuals, and in studies of the pathomechanics of carpal tunnel syndrome

Age-related decrements in dual-task performance: comparison of different mobility and cognitive tasks. A cross sectional study

This cross-sectional study investigated the age-related differences in dual-task performance both in mobility and cognitive tasks and the additive dual-task costs in a sample of older, middle-aged and young adults. 74 older adults (M = 72.63±5.57 years), 58 middle-aged adults (M = 46.69±4.68 years) and 63 young adults (M = 25.34±3.00 years) participated in the study. Participants performed different mobility and subtraction tasks under both single- and dual-task conditions. Linear regressions, repeated-measures and one-way analyses of covariance were used, The results showed: significant effects of the age on the dual and mobility tasks (p<0.05) and differences among the age-groups in the combined dual-task costs (p<0.05); significant decreases in mobility performance under dual-task conditions in all groups (p<0.05) and a decrease in cognitive performance in the older group (p<0.05). Dual-task activity affected mobility and cognitive performance, especially in older adults who showed a higher dual-task cost, suggesting that dual-tasks activities are affected by the age and consequently also mobility and cognitive tasks are negatively influenced

Effects of Dietary Restriction on Cancer Development and Progression

The effects of caloric restriction on tumor growth and progression are known for over a century. Indeed, fasting has been practiced for millennia, but just recently has emerged the protective role that it may exert toward cells. Fasting cycles are able to reprogram the cellular metabolism, by inducing protection against oxidative stress and prolonging cellular longevity. The reduction of calorie intake as well as short- or long-term fasting has been shown to protect against chronic and degenerative diseases, such as diabetes, cardiovascular pathologies, and cancer. In vitro and in vivo preclinical models showed that different restriction dietary regimens may be effective against cancer onset and progression, by enhancing therapy response and reducing its toxic side effects. Fasting-mediated beneficial effects seem to be due to the reduction of inflammatory response and downregulation of nutrient-related signaling pathways able to modulate cell proliferation and apoptosis. In this chapter, we will discuss the most significant studies present in literature regarding the molecular mechanisms by which dietary restriction may contribute to prevent cancer onset, reduce its progression, and positively affect the response to the treatments

A Trigger Enzyme in Mycoplasma pneumoniae: Impact of the Glycerophosphodiesterase GlpQ on Virulence and Gene Expression

Mycoplasma pneumoniae is a causative agent of atypical pneumonia. The formation of hydrogen peroxide, a product of glycerol metabolism, is essential for host cell cytotoxicity. Phosphatidylcholine is the major carbon source available on lung epithelia, and its utilization requires the cleavage of deacylated phospholipids to glycerol-3-phosphate and choline. M. pneumoniae possesses two potential glycerophosphodiesterases, MPN420 (GlpQ) and MPN566. In this work, the function of these proteins was analyzed by biochemical, genetic, and physiological studies. The results indicate that only GlpQ is an active glycerophosphodiesterase. MPN566 has no enzymatic activity as glycerophosphodiesterase and the inactivation of the gene did not result in any detectable phenotype. Inactivation of the glpQ gene resulted in reduced growth in medium with glucose as the carbon source, in loss of hydrogen peroxide production when phosphatidylcholine was present, and in a complete loss of cytotoxicity towards HeLa cells. All these phenotypes were reverted upon complementation of the mutant. Moreover, the glpQ mutant strain exhibited a reduced gliding velocity. A comparison of the proteomes of the wild type strain and the glpQ mutant revealed that this enzyme is also implicated in the control of gene expression. Several proteins were present in higher or lower amounts in the mutant. This apparent regulation by GlpQ is exerted at the level of transcription as determined by mRNA slot blot analyses. All genes subject to GlpQ-dependent control have a conserved potential cis-acting element upstream of the coding region. This element overlaps the promoter in the case of the genes that are repressed in a GlpQ-dependent manner and it is located upstream of the promoter for GlpQ-activated genes. We may suggest that GlpQ acts as a trigger enzyme that measures the availability of its product glycerol-3-phosphate and uses this information to differentially control gene expression

The effects of weaning methods on gut microbiota composition and horse physiology

Weaning has been described as one of the most stressful events in the life of horses. Given the importance of the interaction between the gut-brain axis and gut microbiota under stress, we evaluated (i) the effect of two different weaning methods on the composition of gut microbiota across time and (ii) how the shifts of gut microbiota composition after weaning affect the host. A total of 34 foals were randomly subjected to a progressive (P) or an abrupt (A) weaning method. In the P method, mares were separated from foals at progressively increasing intervals every day, starting from five min during the fourth week prior to weaning and ending with 6 h during the last week before weaning. In the A method, mares and foals were never separated prior to weaning (0 d). Different host phenotypes and gut microbiota composition were studied across 6 age strata (days -30, 0, 3, 5, 7, and 30 after weaning) by 16S rRNA gene sequencing. Results revealed that the beneficial species belonging to Prevotella, Paraprevotella, and Ruminococcus were more abundant in the A group prior to weaning compared to the P group, suggesting that the gut microbiota in the A cohort was better adapted to weaning. Streptococcus, on the other hand, showed the opposite pattern after weaning. Fungal loads, which are thought to increase the capacity for fermenting the complex polysaccharides from diet, were higher in P relative to A. Beyond the effects of weaning methods, maternal separation at weaning markedly shifted the composition of the gut microbiota in all foals, which fell into three distinct community types at 3 days post-weaning. Most genera in community type 2 (i.e., Eubacterium, Coprococcus, Clostridium XI, and Blautia spp.) were negatively correlated with salivary cortisol levels, but positively correlated with telomere length and N-butyrate production. Average daily gain was also greater in the foals harboring a community type 2 microbiota. Therefore, community type 2 is likely to confer better stress response adaptation following weaning. This study identified potential microbial biomarkers that could predict the likelihood for physiological adaptations to weaning in horses, although causality remains to be addressed

MnemoCity Task: Assessment of Childrens Spatial Memory Using Stereoscopy and Virtual Environments

[EN] This paper presents the MnemoCity task, which is a 3D application that introduces the user into a totally 3D virtual environment to evaluate spatial short-term memory. A study has been carried out to validate the MnemoCity task for the assessment of spatial short-term memory in children, by comparing the children s performance in the developed task with current approaches. A total of 160 children participated in the study. The task incorporates two types of interaction: one based on standard interaction and another one based on natural interaction involving physical movement by the user. There were no statistically significant differences in the results of the task using the two types of interaction. Furthermore, statistically significant differences were not found in relation to gender. The correlations between scores were obtained using the MnemoCity task and a traditional procedure for assessing spatial short-term memory. Those results revealed that the type of interaction used did not affect the performance of children in the MnemoCity task.This work was funded mainly by the Spanish Ministry of Economy and Competitiveness (MINECO) through the CHILDMNEMOS project (TIN2012-37381-C02-01) and confinanced by the European Regional Development Fund (FEDER). Other financial support was received from the Gobierno de Aragon (Departamento de Industria e Innovacion), and Fondo Social Europeo for Aragon.Rodríguez-Andrés, D.; Juan, M.; Mendez Lopez, M.; Pérez Hernández, E.; Lluch Crespo, J. (2016). MnemoCity Task: Assessment of Childrens Spatial Memory Using Stereoscopy and Virtual Environments. PLoS ONE. 11(8):1-28. https://doi.org/10.1371/journal.pone.0161858S12811

Review of the projected impacts of climate change on coastal fishes in southern Africa

The coastal zone represents one of the most economically and ecologically important ecosystems on the planet, none more so than in southern Africa. This manuscript examines the potential impacts of climate change on the coastal fishes in southern Africa and provides some of the first information for the Southern Hemisphere, outside of Australasia. It begins by describing the coastal zone in terms of its physical characteristics, climate, fish biodiversity and fisheries. The region is divided into seven biogeographical zones based on previous descriptions and interpretations by the authors. A global review of the impacts of climate change on coastal zones is then applied to make qualitative predictions on the likely impacts of climate change on migratory, resident, estuarine-dependent and catadromous fishes in each of these biogeographical zones. In many respects the southern African region represents a microcosm of climate change variability and of coastal habitats. Based on the broad range of climate change impacts and life history styles of coastal fishes, the predicted impacts on fishes will be diverse. If anything, this review reveals our lack of fundamental knowledge in this field, in particular in southern Africa. Several research priorities, including the need for process-based fundamental research programs are highlighted