Can an aversive, extinction-resistant memory trigger impairments in walking adaptability? An experimental study using adult rats

Cognitive demands can influence the adaptation of walking, a crucial skill to maintain body stability and prevent falls. Whilst previous research has shown emotional load tunes goal-directed movements, little attention has been given to this finding. This study sought to assess the effects of suffering an extinction-resistant memory on skilled walking performance in adult rats, as an indicator of walking adaptability. Thus, 36 Wistar rats were divided in a two-part experiment. In the first part (n = 16), the aversive, extinction-resistance memory paradigm was established using a fear-conditioning chamber. In the second, rats (n = 20) were assessed in a neutral room using the ladder rung walking test before and tree days after inducing an extinction-resistance memory. In addition, the elevated plus-maze test was used to control the influence of the anxiety-like status on gait adaptability. Our results revealed the shock group exhibited worse walking adaptability (lower skilled walking score), when compared to the sham group. Moreover, the immobility time in the ladder rung walking test was similar to the controls, suggesting that gait adaptability performance was not a consequence of the fear generalization. No anxiety-like behavior was observed in the plus maze test. Finally, correlation coefficients also showed the skilled walking performance score was positively correlated with the number of gait cycles and trial time in the ladder rung walking test and the total crossings in the plus maze. Overall, these preliminary findings provide evidence to hypothesize an aversive, extinction-resistant experience might change the emotional load, affecting the ability to adapt walking

Discovery of frequent episodes in event logs

Lion's share of process mining research focuses on the discovery of end-to-end process models describing the characteristic behavior of observed cases. The notion of a process instance (i.e., the case) plays an important role in process mining. Pattern mining techniques (such as frequent itemset mining, association rule learning, sequence mining, and traditional episode mining) do not consider process instances. An episode is a collection of partially ordered events. In this paper, we present a new technique (and corresponding implementation) that discovers frequently occurring episodes in event logs thereby exploiting the fact that events are associated with cases. Hence, the work can be positioned in-between process mining and pattern mining. Episode discovery has its applications in, amongst others, discovering local patterns in complex processes and conformance checking based on partial orders. We also discover episode rules to predict behavior and discover correlated behaviors in processes. We have developed a ProM plug-in that exploits efficient algorithms for the discovery of frequent episodes and episode rules. Experimental results based on real-life event logs demonstrate the feasibility and usefulness of the approach

Size Evolution of Ordered SiGe Islands Grown by Surface Thermal Diffusion on Pit-Patterned Si(100) Surface

The ordered growth of self-assembled SiGe islands by surface thermal diffusion in ultra high vacuum from a lithographically etched Ge stripe on pit-patterned Si(100) surface has been experimentally investigated. The total surface coverage of Ge strongly depends on the distance from the source stripe, as quantitatively verified by Scanning Auger Microscopy. The size distribution of the islands as a function of the Ge coverage has been studied by coupling atomic force microscopy scans with Auger spectro-microscopy data. Our observations are consistent with a physical scenario where island positioning is essentially driven by energetic factors, which predominate with respect to the local kinetics of diffusion, and the growth evolution mainly depends on the local density of Ge atoms

Investigação de um sistema de alimentação em recém-nascidos prematuros a partir de estimulação gustativa

Objetivo: investigar a existência do sistema de alimentação em recém-nascidos prematuros a partir da estimulação gustativa. Métodos: estudo experimental, analítico, duplo-cego. Participaram 90 recém-nascidos prematuros, de uma maternidade pública de Sergipe. O teste foi filmado, constituindo-se por três momentos de cinco minutos. O primeiro e último momento sem realizar estímulo, o segundo momento com estimulação gustativa, sendo que os recém-nascidos foram divididos em dois grupos (água ou sacarose). Foram estudados os comportamentos específicos sucção de mão direita e esquerda, protrusão de língua e movimentos de sucção nos estados comportamentais sono profundo, sono leve, sonolento, agitado/irritado e choro. Para caracterizar a população foram utilizadas média, desvio-padrão e prevalências. Foi utilizado o teste não paramétrico Mann-Whitney para comparação de médias. O teste de Spearman verificou correlação entre estados comportamentais e comportamentos específicos em cada momento do teste. O valor de p foi significante quando menor que 0,05. Resultados: independente do estímulo administrado, a correlação aumentou em todos os comportamentos específicos. Comparando os grupos separadamente, após a estimulação, observou-se aumento de correlação em sucção de mão direita e protrusão de língua para ambos os grupos. O mesmo aconteceu em sucção, com exceção do estado agitado/irritado. Após a estimulação, houve maior correlação para o comportamento de sucção de mão esquerda no grupo sacarose quando comparado ao grupo água. Os resultados evidenciam que estímulos gustativos podem contribuir na prontidão para alimentação nesta população. Conclusões: evidenciou-se nos recém-nascidos prematuros aumento de correlação para os comportamentos específicos relacionados ao sistema de alimentação, após estimulação oral, o que vislumbra a possibilidade da estimulação gustativa ser utilizada para ativação de um sistema de alimentação em recém-nascidos prematuros. _________________________________________________________________________________________ ABSTRACT: Purpose: to investigate the existence of the alimentation system in premature newborns in response to gustatory stimulation. Methods: experimental, analytical, double-blind study. 90 premature newborns of a public maternity in Sergipe took part in the test which was filmed and divided into three parts of five minutes. In the first and last, there was no stimulus; in the second, the gustatory stimulation was applied and the newborn children were divided into two groups (water or sucrose). We studied the specific behaviors suction right and left hands, tongue protrusion and suction movements in behavioral states deep sleep, light sleep, drowsy, restless / irritable and crying. In the statistical analysis of the population, average, standard deviation and prevalence studies were performed. We used the non-parametric Mann-Whitney test to compare averages. The Spearman test observed correlation between behavioral states at each time of the test. The p value was significant when less than 0.05. Results: independent of the given stimulus, the correlation increased in all specific behaviors. Comparing the groups separately, after stimulation, we observed an increase in correlation in right hand suction and tongue protrusion for both. The same happened in suction, except for the agitated/irritated state. After stimulation, there was a higher correlation to the behavior of left hand suction in the sucrose group when compared to water. The results show that gustatory stimuli may contribute to the readiness to feed this population. Conclusions: it was found in premature newborns an increased in correlation for the specific behaviors related to the alimentation system after oral stimulation, which envisions the possibility of gustatory stimulation be used for activating a alimentation system in premature newborns

The porin and the permeating antibiotic: A selective diffusion barrier in gram-negative bacteria

Gram-negative bacteria are responsible for a large proportion of antibiotic resistant bacterial diseases. These bacteria have a complex cell envelope that comprises an outer membrane and an inner membrane that delimit the periplasm. The outer membrane contains various protein channels, called porins, which are involved in the influx of various compounds, including several classes of antibiotics. Bacterial adaptation to reduce influx through porins is an increasing problem worldwide that contributes, together with efflux systems, to the emergence and dissemination of antibiotic resistance. An exciting challenge is to decipher the genetic and molecular basis of membrane impermeability as a bacterial resistance mechanism. This Review outlines the bacterial response towards antibiotic stress on altered membrane permeability and discusses recent advances in molecular approaches that are improving our knowledge of the physico-chemical parameters that govern the translocation of antibiotics through porin channel

Influence of the different “patient global assessment” formulations on disease activity score by different indices in rheumatoid arthritis

© 2018, International League of Associations for Rheumatology (ILAR). Patient global assessment (PGA) is included in almost all rheumatoid arthritis (RA) composite disease activity indices and definitions of remission. However, different PGA formulations exist and are used interchangeably in research and clinical practice. We investigated how five different PGA formulations used in four disease indices affect the remission rates. This was an ancillary analysis of data from a cross-sectional study in patients with RA. The data comprised the following: 28-joint counts, C-reactive protein, and five PGA formulations. Remission rate variation was assessed using five PGA formulations in each index (ACR/EULAR Boolean, CDAI, SDAI, and DAS28-CRP). PGA agreement was assessed by the following: Pearson’s correlation; Bland-Altman plots; paired samples t test; and establishing the proportion of patients who scored (i) all formulations within an interval of 20mm and (ii) each formulation ≤ 10mm. This analysis included 191 patients. PGA formulations presented good correlations (≥ 0.65), but Bland-Altman plots showed clinically significant differences, which were statistically confirmed by comparison of means. Just over a half (51.8%) of patients scored all PGA formulations within a 20-mm interval. The proportion of those scoring ≤ 10mm varied from 11.5 to 16.2%. When different formulations of PGA were used in each index, remission differences of up to 4.7, 4.7, 6.3, and 5.2% were observed. When formulations were used in their respective indices, as validated, the remission rates were similar (13.1, 13.6, 14.1, and 18.3%). Using PGA formulations interchangeably may have implications in the assessment of disease activity and in the attainment of remission, and this can impact upon management decisions

Fluorescence-Based Methods for Detecting Caries Lesions: Systematic Review, Meta-Analysis and Sources of Heterogeneity

Background Fluorescence-based methods have been proposed to aid caries lesion detection. Summarizing and analysing findings of studies about fluorescence-based methods could clarify their real benefits. Objective We aimed to perform a comprehensive systematic review and meta-analysis to evaluate the accuracy of fluorescence-based methods in detecting caries lesions. Data Source Two independent reviewers searched PubMed, Embase and Scopus through June 2012 to identify papers/articles published. Other sources were checked to identify non-published literature. Study Eligibility Criteria, Participants and Diagnostic Methods The eligibility criteria were studies that: (1) have assessed the accuracy of fluorescence-based methods of detecting caries lesions on occlusal, approximal or smooth surfaces, in both primary or permanent human teeth, in the laboratory or clinical setting; (2) have used a reference standard; and (3) have reported sufficient data relating to the sample size and the accuracy of methods. Study Appraisal and Synthesis Methods A diagnostic 2×2 table was extracted from included studies to calculate the pooled sensitivity, specificity and overall accuracy parameters (Diagnostic Odds Ratio and Summary Receiver-Operating curve). The analyses were performed separately for each method and different characteristics of the studies. The quality of the studies and heterogeneity were also evaluated. Results Seventy five studies met the inclusion criteria from the 434 articles initially identified. The search of the grey or non-published literature did not identify any further studies. In general, the analysis demonstrated that the fluorescence-based method tend to have similar accuracy for all types of teeth, dental surfaces or settings. There was a trend of better performance of fluorescence methods in detecting more advanced caries lesions. We also observed moderate to high heterogeneity and evidenced publication bias. Conclusions Fluorescence-based devices have similar overall performance; however, better accuracy in detecting more advanced caries lesions has been observed