Use of Wavelet Transforms and Detrended Fluctuation Analysis in the evaluation of human skin microcirculation

Laser Doppler Flowmetry (LDF) is a non-invasive technique used to assess microvascular flow oscillations. Skin microcirculation has been shown to contain oscillation components with characteristic frequency ranges. These are related to heart, respiration, and myogenic, sympathetic and metabolic activities. So, the evaluation of each component in time may hold important information regarding blood flow physiology. LDF measurements were done at the ankle of 9 female healthy subjects during ankle perfusion restriction using a cuff. Wavelet Transform and Detrended Fluctuation Analysis (DFA) were applied to LDF signals to derive component´s amplitude ratios and a exponents. Parameters were compared in rest, during perfusion restriction, and in recovery after the cuff release. During perfusion restriction a significant increase of heart, respiratory and myogenic components' parameters was observed, suggesting vasoconstriction. Metabolic parameters exhibited a decrease that could be related to NO release changes from the endothelium. Finally, after cuff release a recovery of both amplitude ratios and a exponents was noted, particularly in the respiratory, myogenic and metabolic components. Combined analysis of wavelet component amplitudes with DFAderived exponents can provide a new and more complete picture of microvascular blood-flow regulation

Utilização de nanopartículas de TIO2 para o desenvolvimento de pavimentos rodoviários com capacidade fotocatalítica

A utilização de nanomateriais na indústria de construção rodoviária representa uma opção estrategicamente inovadora que visa a modificação dos materiais convencionais. Neste âmbito, dotar a superfície dos pavimentos rodoviários de capacidade fotocatalítica contribuirá para efetuar a despoluição do ar e a redução da sujidade adsorvida nestas superfícies, aumentando a segurança rodoviária uma vez que minimiza a presença de óleos e gorduras adsorvidos pelas mesmas. Neste trabalho, misturas asfálticas convencionais foram modificadas pela adição de nanopartículas de TiO2 através de dois processos diferentes: inclusão em volume e por aspersão superficial de uma solução aquosa de nanopartículas de TiO2. As misturas asfálticas foram caracterizadas quimicamente e a sua morfologia e capacidade fotocatalítica foram avaliadas. Os resultados obtidos demonstram que a utilização de nanopartículas de TiO2 (aplicadas na superfície pela técnica de aspersão) permitiu obter misturas asfálticas com elevada capacidade fotocatalítica, já que o rendimento de fotodegradação foi superior a 50%.FEDE

Understanding the complete reservoir of bacteriophage depolymerases against A. baumannii capsules

A. baumannii is an important nosocomial and drug-resistant pathogen. The capsule is a major virulence factor that helps bacteria to avoid host immunity and viral predation. Acinetobacter phages can bind and degrade host capsules through capsular depolymerases with proven anti-virulence activity (1-3). Understanding the full reservoir of phage depolymerases against A. baumannii capsules, as well as relevant capsular types in clinical isolates, is crucial for developing depolymerase-based treatments. In this work, we 1) characterized 94 carbapenem-resistant A. baumannii Portuguese isolates; 2) isolated phages for relevant capsular types and characterized their depolymerases and 3) developed bioinformatic tools to collect the diversity of phage depolymerases. We show clonal shifts of A. baumannii KL2, KL7, KL9 and KL120 serotypes over time, with different virulence assessed in G. mellonella. Acinetobacter phages specific for particular k-types were isolated and several depolymerases (for KL1, KL2/KL19, KL9, KL30/KL45, KL32, KL38, KL44, KL67 types) characterized. We also demonstrate that most Acinetobacter phages encode capsular depolymerases (from 134 deposited in 2021, 73 contain capsular depolymerases), exclusively located in small viruses (<90 kb). To disclose the full genetic diversity, we developed PhageDPO (available in Galaxy uminho.pt server), a machine learning tool that identifies depolymerases in phages and bacteria genomes (prophages). We also present PhageKDB, a database that compiles available information of capsular depolymerases, retrieved through both manually and text-mining approaches, serving as an open portal to phage community. Overall, we present novel insights into A. baumannii isolates and phage depolymerase diversity and a collaborative tool to advance research in the field.info:eu-repo/semantics/publishedVersio

Measuring Generalization of Visuomotor Perturbations in Wrist Movements Using Mobile Phones

Recent studies in motor control have shown that visuomotor rotations for reaching have narrow generalization functions: what we learn during movements in one direction only affects subsequent movements into close directions. Here we wanted to measure the generalization functions for wrist movement. To do so we had 7 subjects performing an experiment holding a mobile phone in their dominant hand. The mobile phone's built in acceleration sensor provided a convenient way to measure wrist movements and to run the behavioral protocol. Subjects moved a cursor on the screen by tilting the phone. Movements on the screen toward the training target were rotated and we then measured how learning of the rotation in the training direction affected subsequent movements in other directions. We find that generalization is local and similar to generalization patterns of visuomotor rotation for reaching

Using data linkage to electronic patient records to assess the validity of selected mental health diagnoses in English Hospital Episode Statistics (HES)

<div><p>Background</p><p>Administrative data can be used to support research, such as in the UK Biobank. Hospital Episode Statistics (HES) are national data for England that include contain ICD-10 diagnoses for inpatient mental healthcare episodes, but the validity of these diagnoses for research purposes has not been assessed.</p><p>Methods</p><p>250 peoples' HES records were selected based on a HES recorded inpatient stay at the South London and Maudsley NHS Foundation Trust with a diagnosis of schizophrenia, a wider schizophrenia spectrum disorder, bipolar affective disorder or unipolar depression. A gold-standard research diagnosis was made using Clinical Records Interactive Search pseudonymised electronic patient records using, and the OPCRIT+ algorithm.</p><p>Results</p><p>Positive predictive value at the level of lifetime psychiatric disorder was 100%, and at the level of lifetime diagnosis in the four categories of schizophrenia, wider schizophrenia spectrum, bipolar or unipolar depression was 73% (68–79). Agreement varied by diagnosis, with schizophrenia having the highest PPV at 90% (80–96). Each person had an average of five psychiatric HES records. An algorithm that looked at the last recorded psychiatric diagnosis led to greatest overall agreement with the research diagnosis.</p><p>Discussion</p><p>For people who have a HES record from a psychiatric admission with a diagnosis of schizophrenia spectrum disorder, bipolar affective disorder or unipolar depression, HES records appear to be a good indicator of a mental disorder, and can provide a diagnostic category with reasonable certainty. For these diagnoses, HES records can be an effective way of ascertaining psychiatric diagnosis.</p></div

Conserved and highly expressed tRNA derived fragments in zebrafish

Background: Small non-coding RNAs (sncRNAs) are a class of transcripts implicated in several eukaryotic regulatory mechanisms, namely gene silencing and chromatin regulation. Despite significant progress in their identification by next generation sequencing (NGS) we are still far from understanding their full diversity and functional repertoire. Results: Here we report the identification of tRNA derived fragments (tRFs) by NGS of the sncRNA fraction of zebrafish. The tRFs identified are 18–30 nt long, are derived from specific 5′ and 3′ processing of mature tRNAs and are differentially expressed during development and in differentiated tissues, suggesting that they are likely produced by specific processing rather than random degradation of tRNAs. We further show that a highly expressed tRF (5′tRF-ProCGG) is cleaved in vitro by Dicer and has silencing ability, indicating that it can enter the RNAi pathway. A computational analysis of zebrafish tRFs shows that they are conserved among vertebrates and mining of publicly available datasets reveals that some 5′tRFs are differentially expressed in disease conditions, namely during infection and colorectal cancer. Conclusions: tRFs constitute a class of conserved regulatory RNAs in vertebrates and may be involved in mechanisms of genome regulation and in some diseases. Keywords: tRNA derived fragments, Zebrafish, Small non coding RNAs, tRNAspublishe

Bayesian Integration and Non-Linear Feedback Control in a Full-Body Motor Task

A large number of experiments have asked to what degree human reaching movements can be understood as being close to optimal in a statistical sense. However, little is known about whether these principles are relevant for other classes of movements. Here we analyzed movement in a task that is similar to surfing or snowboarding. Human subjects stand on a force plate that measures their center of pressure. This center of pressure affects the acceleration of a cursor that is displayed in a noisy fashion (as a cloud of dots) on a projection screen while the subject is incentivized to keep the cursor close to a fixed position. We find that salient aspects of observed behavior are well-described by optimal control models where a Bayesian estimation model (Kalman filter) is combined with an optimal controller (either a Linear-Quadratic-Regulator or Bang-bang controller). We find evidence that subjects integrate information over time taking into account uncertainty. However, behavior in this continuous steering task appears to be a highly non-linear function of the visual feedback. While the nervous system appears to implement Bayes-like mechanisms for a full-body, dynamic task, it may additionally take into account the specific costs and constraints of the task

Retinoic acid regulates avian lung branching through a molecular network

Retinoic acid (RA) is of major importance during vertebrate embryonic development and its levels need to be strictly regulated otherwise congenital malformations will develop. Through the action of specific nuclear receptors, named RAR/RXR, RA regulates the expression of genes that eventually influence proliferation and tissue patterning. RA has been described as crucial for different stages of mammalian lung morphogenesis, and as part of a complex molecular network that contributes to precise organogenesis; nonetheless, nothing is known about its role in avian lung development. The current report characterizes, for the first time, the expression pattern of RA signaling members (stra6, raldh2, raldh3, cyp26a1, rar alpha, and rar beta) and potential RA downstream targets (sox2, sox9, meis1, meis2, tgf beta 2, and id2) by in situ hybridization. In the attempt of unveiling the role of RA in chick lung branching, in vitro lung explants were performed. Supplementation studies revealed that RA stimulates lung branching in a dose-dependent manner. Moreover, the expression levels of cyp26a1, sox2, sox9, rar beta, meis2, hoxb5, tgf beta 2, id2, fgf10, fgfr2, and shh were evaluated after RA treatment to disclose a putative molecular network underlying RA effect. In situ hybridization analysis showed that RA is able to alter cyp26a1, sox9, tgf beta 2, and id2 spatial distribution; to increase rar beta, meis2, and hoxb5 expression levels; and has a very modest effect on sox2, fgf10, fgfr2, and shh expression levels. Overall, these findings support a role for RA in the proximal-distal patterning and branching morphogenesis of the avian lung and reveal intricate molecular interactions that ultimately orchestrate branching morphogenesis.The authors would like to thank Ana Lima for slide sectioning and Rita Lopes for contributing to the initiation of this project. This work has been funded by FEDER funds, through the Competitiveness Factors Operational Programme (COMPETE), and by National funds, through the Foundation for Science and Technology (FCT), under the scope of the Project POCI-01-0145-FEDER-007038; and by the Project NORTE-01-0145- FEDER-000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio