Can growth of nannochloropsis oculata under modulated stress enhance its lipid-associated biological properties?

Nannochloropsis oculata is well-recognized as a potential microalgal source of valuable compounds such as polyunsaturated fatty acids, particularly, eicosapentaenoic acid (EPA). The content and profile of these lipids is highly dependent on the growth conditions and can, therefore, be tailored through modulation of the growth parameters, specifically, temperature. Moreover, biological activities are composition dependent. In the present work, lipid extracts obtained from N. oculata, grown under constant temperature and under modulated temperature stress (to increase EPA content; Str) were characterized by GC-FID and several bioactivities were evaluated, namely, antioxidant (L-ORACFL), cytotoxic (MTT), adipolytic, anti-hepatic lipid accumulation (steatosis), and anti-inflammatory properties. Both extracts exhibited antioxidant activity (c.a. 49 µmol Troloxequivalent/mgextract) and the absence of toxicity (up to 800 µg/mL) toward colon and hepatic cells, adipocytes, and macrophages. They also induced adipolysis and the inhibition of triglycerides hepatic accumulation, with a higher impact from Str. In addition, anti-inflammatory activity was observed in the lipopolysaccharide-induced inflammation of macrophages in the presence of either extract, since lower levels of pro-inflammatory interleukin-6 and interferon-β were obtained, specifically by Str. The results presented herein revealed that modulated temperature stress may enhance the health effects of N. oculata lipid extracts, which may be safely utilized to formulate novel food products.info:eu-repo/semantics/publishedVersio

Strategies to improve hand hygiene practices: an integrative literature review

Background: Healthcare-associated infections (HAIs) are a global concern and pose a real threat to patient safety. Many of them preventable [1]. Knowing that hands of healthcare professionals are one of the main vehicles in the transmission of microorganisms, hand hygiene (HH) is recognized as the easier and most effective measure to prevent and reduce HAIs [2]. However, despite all evidence available and although 98% of healthcare professionals consider HH as the most important basic precaution in preventing HAIs, compliance is poor, remaining less than 40% [3,4]. Objective: To identify, in Literature, the most effective strategies to promote HH compliance. Methods: An integrative review between September and October 2017 was fulfilled with the Boolean strategy: [(TI Title) hand hygiene AND (AB Abstract) nurse AND (AB Abstract) infection AND (AB Abstract) strategy OR compliance OR adherence] in CINAHL®, Science Direct and Academic Search Complete. A total of 396 articles were identified, initially. After applying the inclusion criteria: primary and secondary studies with a qualitative and quantitative approach available in full text in Portuguese, English, French and Spanish; and exclusion criteria: studies published before 2016, a sample of 12 articles was included for analysis. Results: From a total of 12 articles analysed, 10 showed the importance of a multimodal approach to the improvement of HH practices with consequent increase in compliance to this behaviour. It stands out the combination of interventions addressing knowledge (education), awareness, context of action (reminders in the workplace) as well as the involvement and support of leaders and managers in building an institutional safety culture (social influence) as the most effective to ensure greater compliance to HH. Conclusions: In order to improve HH practices and, consequently, adherence to this behaviour, the adoption of a multimodal strategy proved to be more successful when compared to single interventions. At an early stage, it is essential to understand the reasons that lead to non-adherence to HH and after that design interventions based on identified barriers. The approach should be global, including not only healthcare professionals but also leaders and managers.info:eu-repo/semantics/publishedVersio

Modulation of fatty acid profile in nannochloropsis oculata adaptation to temperature stress

info:eu-repo/semantics/publishedVersio

An analysis of the positional distribution of DNA motifs in promoter regions and its biological relevance

BACKGROUND: Motif finding algorithms have developed in their ability to use computationally efficient methods to detect patterns in biological sequences. However the posterior classification of the output still suffers from some limitations, which makes it difficult to assess the biological significance of the motifs found. Previous work has highlighted the existence of positional bias of motifs in the DNA sequences, which might indicate not only that the pattern is important, but also provide hints of the positions where these patterns occur preferentially.RESULTS: We propose to integrate position uniformity tests and over-representation tests to improve the accuracy of the classification of motifs. Using artificial data, we have compared three different statistical tests (Chi-Square, Kolmogorov-Smirnov and a Chi-Square bootstrap) to assess whether a given motif occurs uniformly in the promoter region of a gene. Using the test that performed better in this dataset, we proceeded to study the positional distribution of several well known cis-regulatory elements, in the promoter sequences of different organisms (S. cerevisiae, H. sapiens, D. melanogaster, E. coli and several Dicotyledons plants). The results show that position conservation is relevant for the transcriptional machinery.CONCLUSION: We conclude that many biologically relevant motifs appear heterogeneously distributed in the promoter region of genes, and therefore, that non-uniformity is a good indicator of biological relevance and can be used to complement over-representation tests commonly used. In this article we present the results obtained for the S. cerevisiae data sets.publishersversionpublishe

Effect of the incorporation of salted additives on probiotic whey cheeses

The research effort described here has focused on incorporation of Lactobacillus casei, in whey protein matrices, in the presence of selected salty additives. Those matrices were produced via thermal processing of a combination of either ovine or bovine whey (or a mixture thereof) with ovine milk, and were inoculated (at 10%) with L. casei strain LAFTI®L26; salt, salt and herbs, or salt and xanthan were further added to such matrices, which were then homogenized and stored at 7 °C for up to 21 d. In general, viable cell numbers maintained or even increased throughout the storage period, irrespective of the type of salty additive considered. Partial depletion of lactose was detected, and concomitant production of lactic acid throughout the 21 d-period of storage; lower lactic acid concentrations were found in matrices containing salty additives. In matrices with xanthan (SX), the probiotic strain exhibited the lowest metabolic activity. Matrices SX were less soft and firmer than the others, by the end of storage, and were similar to matrices with herbs (SH). The incorporation of salty additives affected bacterial metabolism, in terms of glycolysis and proteolysis, which in turn had a significant impact on the development of textural propertiesinfo:eu-repo/semantics/acceptedVersio

Cell-to-cell aggregation in S. epidermidis and its effect on quantification of total and viable bacteria within biofilms

Biofilms forming on the surface of indwelling medical devices by microorganisms such as Staphylococcus epidermidis, act as a source of acute infections. Since colonization of medical devices represents a serious problem in public healthcare-associated infections, bacteria forming biofilms have been an important issue often studied. Proper quantification of viable bacteria within S. epidermidis biofilms can however be challenging. Often, biofilm quantification of S. epidermidis is performed with colorimetric methods but these do not provide information regarding viable bacteria. CFU counting is often used but in the case of S. epidermidis, a bacteria that normally grows in clusters of cells, sonication is always required in order to obtain individual cells. In older biofilms, the number of dormant bacteria is expected to be higher than in young biofilms. Therefore, disrupting a biofilm structure without damage the cells in older biofilms can be a challenge. Here, biofilm samples of Staphylococcus epidermidis 9142 strain grown for 24, 48 or 72H in TSB supplemented with 0,5% glucose were ressuspended 1 mL of physiological saline solution and sonicated at different cycles. Following sonication biofilms were quantified using three different approaches: colorimetric methods, CFU counting, and microscopic evaluation using a Neübauer chamber coupled with staining with fluorescence dye LIVE/DEAD® BacLight ™ Bacterial Viability Kit (Molecular Probes Inc). Cell counting was optimized using Sigma Scan Pro and validated against manual counting of the images. In the conditions used, higher numbers of sonication cycles prevented any clustering of cells but were affecting cell viability. On the other hand, lower numbers of sonication cycles were not effective in completely eliminating cell clusters, especially in 72H-old biofilms. The presence of the cell clusters at the lower sonication cycles resulted in high variability of CFU counting. On the other hand, cell counting with a Neübauer chamber was the best way to proper quantify the total and viable bacteria within the biofilms. By using the automatic counting software and validating the methodology, quantification of biofilms was relatively fast and reliable to perform. Keywords Biofilm; Staphylococcus epidermidis; Sonication, automatic cell countin

Optimization of a protocol for gene expression using biofilm cells from S. epidermidis

Gene expression assays are one of the most common tools used nowadays to evaluate the importance of genes in many different life sciences areas, namely, in clinical microbiology. Since most gene expression kits for qPCR have been optimized for assays with planktonic cells it is important to also optimize protocols for this type of assays, to be used with biofilms. Biofilms are communities of bacteria that grow attached to a surface and embedded in an extracellular matrix, what poses some difficulties to RNA extraction. Proper RNA quality is of the upmost importance during all the downstream processes, namely cDNA synthesis and qPCR quantification. The aim of this work was to optimize a protocol for gene quantification from biofilm samples of S. epidermidis, a known biofilm forming nosocomial pathogen. This optimization was made in many different steps, from the RNA extraction (a crucial step) to complementary DNA (cDNA) synthesis and qPCR reactions, using growth conditions well described in the literature, so that the results obtained could be anticipated beforehand. The expression of the icaA gene was tested from RNA extracted with a custom made protocol and then quantified using a combination of 4 commercial kits of cDNA synthesis and 4 commercial kits of qPCR quantification. Furthermore, the volumes of reaction were either the volume recommended by the manufacturer (20 µl) or half that volume. From our results, we conclude that there were no significant differences of icaA expression when using any of the qPCR kits used in this study. However, using different cDNA synthesis kits, a statistical difference was found in the results obtained using one of the kits, with an icaA expression near 4-fold different than that obtained using the other kits. Interestingly, the 10 µl reaction generally resulted in higher icaA expression than when using the 20 µl reaction volume, but within the expected range of values, indicating that any of the two volumes could be used for quantification studies. Excluding the cDNA kit with low icaA levels expression, the average of icaA expression induced by glucose was similar in both cDNA and qPCR optimization steps (9.5 and 9.4 fold, respectively). The obtained protocol provides reliable results, comparable to the ones in literature, with the advantage of saving reagents. Furthermore, our results confirm that cDNA synthesis is a more crucial step that previous thought

The impact of a curriculum for resilience promotion in deaf children and adolescents

Resilience is an interactive process involving internal skills that should be promoted, especially in the early stages of development. This study aims to adapt and implement two themes from the European Curriculum for Resilience Promotion – RESCUR, namely, ‘Developing Communication Skills’ and ‘Establishing and Maintaining Healthy Relationships’, for deaf and hard-of-hearing (DHH) students. The study included 37 children and adolescents from three Portuguese regions and its impact was evaluated through the perspectives of the students, their guardians and their teachers. Each 90-minute session was implemented weekly. The sessions followed the RESCUR curriculum structure with necessary adaptations to the mindfulness activities, stories, role-play and worksheets. The mean scores increased from pre- to post-intervention assessment on all instruments, namely, KIDSCREEN-10 (children/adolescents), KIDSCREEN-10 (guardians) and CYRM-28 (teachers). The implementation of adapted curricula promoting resilience seems to be beneficial to DHH children, allowing the development of specific resilience-associated skills, and thus enhancing health, well-being and quality of life.info:eu-repo/semantics/publishedVersio

In vitro fermentation and prebiotic potential of selected extracts from seaweeds and mushrooms

Extracts with prebiotic activity or bioactive compounds from natural sources such as seaweeds or mushrooms, combining a broad spectrum of biological properties, may offer great potential for their use as functional ingredients enabling intestinal microbiota modulation. In this context, selected enzymatic extracts from Sargassum muticum, Osmundea pinnatifida and Pholiota nameko were evaluated in vitro. Faecal fermentations were conducted anaerobically under controlled temperature and pH over 24 h. Enzymatic extracts of Ph. nameko and of O. pinnatifida at 1% (w/v), lead to increases in Bifidobacterium spp. after 6 h of fermentation in comparison to negative control, suggesting a stimulatory effect. No significant changes over 24 h were observed of Lactobacillus spp. In particular, the Ph. nameko extract obtained with Flavourzyme not only stimulated growth and/or activity of Bifidobacterium spp. but also led to a decrease of Clostridium histolyticum group upon 24 h, thus potentially benefiting colonic health. Higher percentages of this extract (2 and 3%) impaired a C. histolyticum reduction confirming this selective action and prebiotic potential. Differences in short chain fatty acids (SCFA) and lactic acid production between the four extracts may indicate a potential relationship between their physico-chemical properties, which differ in composition and structures, and modulation of gut bacterial species