Nanocarrier-mediated topical insulin delivery for wound healing

Wound care has been clinically demanding due to inefficacious treatment that represents an economic burden for healthcare systems. In Europe, approximately 7 million people are diagnosed with untreated wounds, leading to a cost between 6.000€ and 10.000€ per patient/year. In the United States of America, 1.5 million people over 65 years old suffer from chronic wounds. A promising therapeutic strategy is the use of exogenous growth factors because they are decreased at the wound site, limiting the recovery of the skin. Insulin is one of the cheapest growth factors in the market able to accelerate the re-epithelialization and stimulate angiogenesis and cell migration. However, the effectiveness of topical insulin in wound healing is hampered by the proteases in the wound bed. The encapsulation into nanoparticles improves its stability in the wound, providing adhesion to the mucosal surface and allowing its sustained release. The aim of this review is to perform a standing point about a promising strategy to treat different types of wounds by the topical delivery of insulin-loaded nanocarriers.FEDER—Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020—Operational Programme for Competitiveness and Internationalization(POCI) POCI-01-0145-FEDER-032610, PTDC/MEC-DER/32610/2017, UIDB/50006/2020, UIDB/04326/2020, UIDB/04565/2020info:eu-repo/semantics/publishedVersio

Exploring core cognitive skills of Computational Thinking

Although still innovative and not largely disseminated, Computational Thinking is being considered as a critical skill for students in the 21st century. It involves many skills, but programming abilities seem to be a core aspect since they foster the development of a new way of thinking that is key to the solution of problems that require a combination of human mental power and computing power capacity. This paper presents an exploratory study developed to select psychological assessment tests that can be used to identify and measure Computational Thinking cognitive processes, associated to the programming component, so that strategies can be developed to promote it. After the literature review, we identified four central cognitive processes implied in programming, therefore important to Computational Thinking, and accordingly selected a set of four tests that were administered to a sample of 12 introductory programming students. Our results suggest that spatial reasoning and general intelligence are crucial dimensions for introductory programming, being also correlated to the students’ academic success in this area. However, arithmetic reasoning and attention to detail tests did not correlate. Based on these results, directions for future research have been defined in order to effectively identify and develop the core cognitive processes of programming, ergo, to help develop Computational Thinking.University of Susse

On the Effects of a Workplace Fitness Program upon Pain Perception: a Case Study Encompassing Office Workers in a Portuguese Context

INTRODUCTION Office workers share several behavioural patterns: they work seated without moving for long times, they use only a few specific muscles of their arms, wrists and hands, and they keep an overall poor body posture. These working patterns generate musculoskeletal disorders, and produce discomfort or pain. Implementation of a work fitness program is thus a low-cost strategy to reduce/prevent body pain derived from work. The aim of this study was to test the benefits of a workplace fitness program, specifically applied to an administrative department of a Portuguese enterprise. Recall that this type of primary prevention level of musculoskeletal disorders has been seldom applied in Portugal, so this research effort materialized an important contribution to overcome such a gap. METHODS The participants in this study were office workers (n = 29 in the study group, and n = 21 in the control group)-who consistently had reported pain mostly on their back side (neck, posterior back, and dorsal and lumbar zones), wrists and posterior legs. The workplace fitness program consisted of three sessions per week during an 8-month period, with 15 min per session; emphasis was on stretching exercises for the body regions most affected by workers' pain perception. Each participant was requested to point out the injured region, as well as the intensity of pain felt, by using a visual analogue scale. Statistical analyses of the perceived pain data from control and study groups resort to non-parametric hypothesis tests. RESULTS There was a strong evidence that the workplace fitness program applied was effective in reducing workers' pain perception for their posterior back, dorsal and lumbar zones, and for their right wrist (P < 0.05). CONCLUSIONS These results generated are rather promising, so they may efficiently serve as an example for other enterprises in that country-while raising awareness on the important issue of quality of life at the workplace.info:eu-repo/semantics/publishedVersio

An overview on spray-drying of protein-loaded polymeric nanoparticles for dry powder inhalation

The delivery of therapeutic proteins remains a challenge, despite recent technological advances. While the delivery of proteins to the lungs is the gold standard for topical and systemic therapy through the lungs, the issue still exists. While pulmonary delivery is highly attractive due to its non-invasive nature, large surface area, possibility of topical and systemic administration, and rapid absorption circumventing the first-pass effect, the absorption of therapeutic proteins is still ineffective, largely due to the immunological and physicochemical barriers of the lungs. Most studies using spray-drying for the nanoencapsulation of drugs focus on the delivery of conventional drugs, which are less susceptible to bioactivity loss, compared to proteins. Herein, the development of polymeric nanoparticles by spray-drying for the delivery of therapeutic proteins is reviewed with an emphasis on its advantages and challenges, and the techniques to evaluate their in vitro and in vivo performance. The protein stability within the carrier and the features of the carrier are properly addressed.FCT: UIDB/50006/2020, UIDB/04326/2020, and UIDB/04565/2020.info:eu-repo/semantics/publishedVersio

Identifying cognitive abilities to improve CS1 outcome

Introductory programming courses entail students’ high failure and dropout rates. In an effort to tackle this problem, we carried out a qualitative study aiming to shed some light on the programming phase that is most challenging for students, in order to elicit the specific difficulties they experience while learning to program. In doing so, distinctive cognitive abilities, differentiating subjects in terms of the way they handle programming tasks, were detected. Such aptitudes are represented in three groups of students: those who learn easily, those who never seem to fully grasp what programming requires despite true effort, and those who experience a sudden insight, making them leap from a point were they had difficulties to another where they overcome them. By interviewing teachers and students, abstraction and sequencing elaboration were found to be the two core skills for programming. These results impelled us to consider the mental models’ approach, concluding that there are very specific cognitive functions that are more favorable to learn programming and that are fostered by more adequate schemas of representing reality. Some conclusions involving Problem-based learning as a fit teaching methodology to overcome students’ difficulties are also presented

Comparison of the effects of different anesthetics on serum haemolysis and glycogenolysis in rats

The anesthetics can differently affect the structure and biological function of tissues and systems. The objective of this study was to compare the effects of three injectable anesthetics generally used in experiments with animals on the degree of haemolysis and glycogenolysis after deep anesthesia. 20 Wistar male rats (330-440g) were used. The animals were divided into three groups: Cloral Hydrate (CH), Ketamine + Xylazine (KX), Zoletil 50® (zolazepam and tiletamina) + Xylazine (ZTX). After deep anesthesia the total blood was collected. Immediately the liver, the white and red gastrocnemius muscles were also withdrawn. The degree of serum haemolysis was quantified by the hemoglobin concentration (g/dL) and the hepatic and muscular glycogen concentration through spectrophotometer analyses. The CH and KX groups presented serum haemolysis (0.49 ± 0.06 g/dL and 0.18 ± 0.06 g/dL, respectively). ZTX group presented no detectable values. The average value of the hepatic and muscular glycogen concentrations exhibited no significant difference between CH and ZTX groups. The data were similar to other studies in the literature. However, the KX induced accentuated glycogenolysis in all tissues. Our data suggest that the anesthetic ZTX seems to be the most appropriate for studies that need simultaneously to quantify the concentration of glycogen and blood markers without interferences. It neither causes glycogenolysis nor haemolysis. ZTX possesses accessible cost, is easily found at veterinary markets, quickly induces deep anesthesia and presents low mortality rate

Parenting in Adversity: Effects of Older Caregivers, Biological Carers and Troubled Carers on Child Outcomes in High HIV-Affected Communities

Caregiving by older adults is a common phenomenon, enhanced in the era of HIV infection. This longitudinal study was set up to examine the effect of caregiver age, relationship and mental wellbeing on child (4-13 years) outcomes (psychosocial and cognitive) in a sample of 808 caregiver- child dyads in South Africa and Malawi. Respondents were drawn from consecutive attenders at Community Based Organisations (CBOs) and interviewed with standardised inventories at baseline and followed up 12-15 months later. Analysis focused on three separate aspects of the caregiver; age, relationship to the child, and mental wellbeing, results are stratified with regard to these factors. Results showed that compared to younger caregivers, over 50 years were carrying a heavy load of childcare, but caregiver age for the most part was not associated with child outcomes. Being biologically related to the child (such as biological grandparenting) was also not a significant factor in child outcomes measured. However, irrespective of age and relationship, caregiver mental health was associated with differences in child outcome - those children of caregivers with a greater mental health burden were found to report experiencing more physical and psychologically violent discipline. Over time, the use of violent discipline was found to reduce. These data suggest that older caregivers and grandparents are providing comparable care to younger caregivers, for young children in the face of the HIV epidemic and that interventions should focus on mental health support for all caregivers, irrespective of age or relationship to the child

Evaluation of the antitumour and antiproliferative effect of Xanthohumol-Loaded PLGA nanoparticles on melanoma

Cutaneous melanoma is the deadliest type of skin cancer and current treatment is still inadequate, with low patient survival rates. The polyphenol xanthohumol has been shown to inhibit tumourigenesis and metastasization, however its physicochemical properties restrict its application. In this work, we developed PLGA nanoparticles encapsulating xanthohumol and tested its antiproliferative, antitumour, and migration effect on B16F10, malignant cutaneous melanoma, and RAW 264.7, macrophagic, mouse cell lines. PLGA nanoparticles had a size of 312 ± 41 nm and a PdI of 0.259, while achieving a xanthohumol loading of about 90%. The viability study showed similar cytoxicity between the xanthohumol and xanthohumol-loaded PLGA nanoparticles at 48 h with the IC50 established at 10 µM. Similar antimigration effects were observed for free and the encapsulated xanthohumol. It was also observed that the M1 antitumor phenotype was stimulated on macrophages. The ultimate anti-melanoma effect emerges from an association between the viability, migration and macrophagic phenotype modulation. These results display the remarkable antitumour effect of the xanthohumol-loaded PLGA nanoparticles and are the first advance towards the application of a nanoformulation to deliver xanthohumol to reduce adverse effects by currently employed chemotherapeutics.info:eu-repo/semantics/publishedVersio

S-nitrosoglutathione reverts dietary sucrose-induced insulin resistance

The liver is a fundamental organ to ensure whole-body homeostasis, allowing for a proper increase in insulin sensitivity from the fast to the postprandial status. Hepatic regulation of glucose metabolism is crucial and has been shown to be modulated by glutathione (GSH) and nitric oxide (NO). However, knowledge of the metabolic action of GSH and NO in glucose homeostasis remains incomplete. The current study was designed to test the hypothesis that treatment with S-nitrosoglutathione is sufficient to revert insulin resistance induced by a high-sucrose diet. Male Wistar rats were divided in a control or high-sucrose group. Insulin sensitivity was determined: (i) in the fast state; (ii) after a standardized test meal; (iii) after GSH + NO; and after (iv) S-nitrosoglutathione (GSNO) administration. The fasting glucose level was not different between the control and high-sucrose group. In the liver, the high-sucrose model shows increased NO and unchanged GSH levels. In control animals, insulin sensitivity increased after a meal or administration of GSH+NO/GSNO, but this was abrogated by sucrose feeding. GSNO was able to revert insulin resistance induced by sucrose feeding, in a dose-dependent manner, suggesting that they have an insulin-sensitizing effect in vivo. These effects are associated with an increased insulin receptor and Akt phosphorylation in muscle cells. Our findings demonstrate that GSNO promotes insulin sensitivity in a sucrose-induced insulin-resistant animal model and further implicates that this antioxidant molecule may act as a potential pharmacological tool for the treatment of insulin resistance in obesity and type 2 diabetes.publishersversionpublishe

Texture analysis can be used to improve skin sonography quantification capacities

Image interpretation of sonograms is a difficult process since it largely depends on the observer’s experience and is the limited by image resolution of commercial scanners. Texture analysis offers a range of analysis tools that assess the spatial variation and distribution of gray levels within a given image and translates them into quantitative parameters. We compared non-treated skin, hydrated, and erythema. Texture analysis parameters (entropy, contrast, correlation, energy, homogeneity) were calculated from the epidermis, dermis, and hypodermis selected regions of interest. Entropy, contrast and homogeneity were higher in the more echogenic epidermis, while correlation and energy were higher for the more homogenous dermis. The echo, entropy, contrast and correlation were found to be consistently lower on both layers of the hydrated skin and erythema, while energy was higher. These results suggest that texture analysis is useful to quantitatively describe the differences in skin layers based on their echogenic profile