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1.
PLoS One ; 19(7): e0302563, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985774

RESUMO

Research on personal adornments depends on the reliable characterisation of materials to trace provenance and model complex social networks. However, many analytical techniques require the transfer of materials from the museum to the laboratory, involving high insurance costs and limiting the number of items that can be analysed, making the process of empirical data collection a complicated, expensive and time-consuming routine. In this study, we compiled the largest geochemical dataset of Iberian personal adornments (n = 1243 samples) by coupling X-ray fluorescence compositional data with their respective X-ray diffraction mineral labels. This allowed us to develop a machine learning-based framework for the prediction of bead-forming minerals by training and benchmarking 13 of the most widely used supervised algorithms. As a proof of concept, we developed a multiclass model and evaluated its performance on two assemblages from different Portuguese sites with current mineralogical characterisation: Cova das Lapas (n = 15 samples) and Gruta da Marmota (n = 10 samples). Our results showed that decisión-tres based classifiers outperformed other classification logics given the discriminative importance of some chemical elements in determining the mineral phase, which fits particularly well with the decision-making process of this type of model. The comparison of results between the different validation sets and the proof-of-concept has highlighted the risk of using synthetic data to handle imbalance and the main limitation of the framework: its restrictive class system. We conclude that the presented approach can successfully assist in the mineral classification workflow when specific analyses are not available, saving time and allowing a transparent and straightforward assessment of model predictions. Furthermore, we propose a workflow for the interpretation of predictions using the model outputs as compound responses enabling an uncertainty reduction approach currently used by our team. The Python-based framework is packaged in a public repository and includes all the necessary resources for its reusability without the need for any installation.


Assuntos
Minerais , Minerais/análise , Minerais/química , Algoritmos , Portugal , Difração de Raios X , Espectrometria por Raios X/métodos , Humanos , Aprendizado de Máquina , Aprendizado de Máquina Supervisionado
2.
Nutrients ; 16(11)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38892557

RESUMO

In an increasingly aging and overweight population, osteoporosis and type 2 diabetes (T2DM) are major public health concerns. T2DM patients experience prejudicial effects on their bone health, affecting their physical capacity. Exercise in hypoxia (EH) and a low-carbohydrate diet (LCD) have been suggested for therapeutic benefits in T2DM, improving bone mineral content (BMC) and glycemic control. This study investigated the effects of EH combined with an LCD on body composition and functional and physiologic capacity in T2DM patients. Older T2DM patients (n = 42) were randomly assigned to the following groups: (1) control group: control diet + exercise in normoxia; (2) EH group: control diet + EH; (3) intervention group: LCD + EH. Cardiopulmonary tests (BRUCE protocol), body composition (DEXA), and functional capacity (6MWT, handgrip strength) were evaluated. Body mass index (kg/m2) and body fat (%) decreased in all groups (p < 0.001). BMC (kg) increased in all groups (p < 0.001) and was significantly higher in the EH and EH + LCD groups (p < 0.001). VO2peak improved in all groups (p < 0.001), but more so in the hypoxia groups (p = 0.019). Functional capacity was increased in all groups (p < 0.001), but more so in the EH group in 6MWT (p = 0.030). EH with and without an LCD is a therapeutic strategy for improving bone mass in T2DM, which is associated with cardiorespiratory and functional improvements.


Assuntos
Composição Corporal , Densidade Óssea , Diabetes Mellitus Tipo 2 , Dieta com Restrição de Carboidratos , Hipóxia , Humanos , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/terapia , Masculino , Feminino , Idoso , Dieta com Restrição de Carboidratos/métodos , Hipóxia/fisiopatologia , Pessoa de Meia-Idade , Exercício Físico/fisiologia , Força da Mão , Terapia por Exercício/métodos
3.
Heliyon ; 10(7): e28779, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601558

RESUMO

Consumption of tea and herbal infusions (THIs) have a long history in traditional medicine and cultural practices. The health-promoting benefits attributed to THIs are considered influential factors in consumer choices. However, there is limited data on consumer choices and attitudes that might interfere with the positive effects associated with THIs consumption. The aim of this study was to investigate the consumption pattern and behavior of THIs consumers in Portugal, assessing the influence of socio-demographic factors on the selection of THIs products and consumer practices related to these beverages. An online survey was conducted, and from the collected data, 720 responses met the aim of the study and were further analyzed. Most of the respondents were female, 74.4%, belonging to the 40-60 age group (40.6%) and were medium consumers of THIs (47.2%). Green tea was the most consumed type among participants, and its consumption was associated not only with age but also with the pattern of THIs consumption. Despite that, participants preferred herbal infusions, with citronella, chamomile, and lemon verbena being the most consumed types. For certain types of herbal infusions, consumption was associated with age, while other types were preferred by moderate or heavy consumers. Most participants purchased THIs in supermarkets, registered trademark and brand stores, in the form of THIs bag. Light consumers use only bag, while medium/heavy consumers indicated the use of other forms. Almost half of the respondents admitted to not reading the information on product labels before consumption and using THIs after the expiry date, while only one-third of them declared paying attention to the label instructions. This study revealed the impact of socio-demographic factors as age on the consumption patterns and preferences of THIs of consumers. Of concern is the neglect of label usage among Portuguese consumers. This emphasizes the urgency of implementing interventions to guide proper label use and promote good consumption practices to ensure the quality of THIs products.

4.
Animals (Basel) ; 14(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38338013

RESUMO

Horses are high-performance athletes prone to sportive injuries such as tendonitis and desmitis. The formation of fibrous tissue in tendon repair remains a challenge to overcome. This impels regenerative medicine to develop innovative therapies that enhance regeneration, retrieving original tissue properties. Multipotent Mesenchymal Stem/Stromal Cells (MSCs) have been successfully used to develop therapeutic products, as they secrete a variety of bioactive molecules that play a pivotal role in tissue regeneration. These factors are released in culture media for producing a conditioned medium (CM). The aforementioned assumptions led to the formulation of equine synovial membrane MSCs (eSM-MSCs)-the cellular pool that naturally regenerates joint tissue-combined with a medium enriched in immunomodulatory factors (among other bioactive factors) produced by umbilical cord stroma-derived MSCs (eUC-MSCs) that naturally contribute to suppressing the immune rejection in the maternal-fetal barrier. A description of an equine sport horse diagnosed with acute tarsocrural desmitis and treated with this formulation is presented. Ultrasonographic ligament recovery occurred in a reduced time frame, reducing stoppage time and allowing for the horse's return to unrestricted competition after the completion of a physical rehabilitation program. This study focused on the description of the therapeutic formulation and potential in an equine desmitis treatment using the cells themselves and their secretomes.

5.
Regen Med ; 19(4): 189-203, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37855207

RESUMO

Aim: Peripheral nerve injury regeneration studies using animal models are crucial to different pre-clinical therapeutic approaches efficacy evaluation whatever the surgical technique explored. Materials & methods: A 944 articles systematic review on 'peripheral nerve injury in animal models' over the last 9 years was carried out. Results: It was found that 91% used rodents, and only 9% employed large animals. Different nerves are studied, with generated gaps (10,78 mm) and methods applied for regeneration evaluation uniformed. Sciatic nerve was the most used (88%), followed by median and facial nerves (2.6%), significantly different. Conclusion: There has not been a significant scale-up of the in vivo testing to large animal models (anatomically/physiologically closer to humans), allowing an improvement in translational medicine for clinical cases.


Assuntos
Traumatismos dos Nervos Periféricos , Humanos , Animais , Nervo Isquiático , Modelos Animais , Regeneração Nervosa/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Modelos Animais de Doenças
6.
Life (Basel) ; 13(9)2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37763322

RESUMO

Peripheral nerve injury (PNI) remains a medical challenge with no easy resolution. Over the last few decades, significant advances have been achieved in promoting peripheral nerve regeneration, and new assessment tools have been developed, both functional and imaging, to quantify the proportion and quality of nerve recovery. The exploration of new animal models, larger, more complex, and with more similarities to humans, has made it possible to reduce the gap between the results obtained in classic animal models, such as rodents, and the application of new therapies in humans and animals of clinical interest. Ultrasonography is an imaging technique recurrently used in clinical practice to assess the peripheral nerves, allowing for its anatomical and topographic characterization, aiding in the administration of anesthesia, and in the performance of nerve blocks. The use of this technique in animal models is scarce, but it could be a useful tool in monitoring the progression of nerve regeneration after the induction of controlled experimental lesions. In this work, sheep, a promising animal model in the area of peripheral nerve regeneration, were subjected to an ultrasonographic study of three peripheral nerves of the hind limb, the common peroneal, and tibial and sciatic nerves. The main aim was to establish values of dimensions and ultrasound appearance in healthy nerves and landmarks for their identification, as well as to perform an ultrasound evaluation of the cranial tibial muscle, an effector muscle of the common peroneal nerve, and to establish normal values for its ultrasound appearance and dimensions. The results obtained will allow the use of these data as control values in future work exploring new therapeutic options for nerve regeneration after induction of common peroneal nerve injuries in sheep.

7.
Biomedicines ; 11(8)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37626596

RESUMO

Exosomes have shown promising potential as a therapeutic approach for wound healing. Nevertheless, the translation from experimental studies to commercially available treatments is still lacking. To assess the current state of research in this field, a systematic review was performed involving studies conducted and published over the past five years. A PubMed search was performed for English-language, full-text available papers published from 2018 to June 2023, focusing on exosomes derived from mammalian sources and their application in wound healing, particularly those involving in vivo assays. Out of 531 results, 148 papers were selected for analysis. The findings revealed that exosome-based treatments improve wound healing by increasing angiogenesis, reepithelization, collagen deposition, and decreasing scar formation. Furthermore, there was significant variability in terms of cell sources and types, biomaterials, and administration routes under investigation, indicating the need for further research in this field. Additionally, a comparative examination encompassing diverse cellular origins, types, administration pathways, or biomaterials is imperative. Furthermore, the predominance of rodent-based animal models raises concerns, as there have been limited advancements towards more complex in vivo models and scale-up assays. These constraints underscore the substantial efforts that remain necessary before attaining commercially viable and extensively applicable therapeutic approaches using exosomes.

8.
Crit Rev Anal Chem ; : 1-25, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37300809

RESUMO

Pyrrolizidine alkaloids (PAs) are natural toxins produced by some plants that gained special interest due to their potential hazardous effects in humans and animals. These substances have been found in wild flora, herbal medicines and food products raising health concerns. Recently, maximum concentration levels of PAs were established for some food products; however, maximum daily intake frequently surpasses the upper limit set by the competent authorities posing a health risk. Given the scarcity or absence of occurrence data on PAs in many products, there is an urgent need to measure their levels and establish safety intake levels. Analytical methods have been reported to detect and quantify PAs in different matrices. The commonly used chromatographic methodologies provides accurate and reliable results. Analytical methods include diverse steps as extraction and sample preparation procedures that are critical for sensitivity and selectivity of the analytical method. Great efforts have been directed toward optimization of extraction procedures, clean up and chromatographic conditions to improve recovery, reduce matrix effects, and achieve low limits of detection and quantification. Therefore, this paper aims to give a general overview about the occurrence of PAs in flora, herbal medicines, and foodstuff; and discuss the different chromatographic methodologies used for PAs analysis, namely extraction and sample preparation procedures and chromatographic conditions.

9.
Animals (Basel) ; 13(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37106875

RESUMO

Tendon and ligament injuries are frequent in sport horses and humans, and such injuries represent a significant therapeutic challenge. Tissue regeneration and function recovery are the paramount goals of tendon and ligament lesion management. Nowadays, several regenerative treatments are being developed, based on the use of stem cell and stem cell-based therapies. In the present study, the preparation of equine synovial membrane mesenchymal stem cells (eSM-MSCs) is described for clinical use, collection, transport, isolation, differentiation, characterization, and application. These cells are fibroblast-like and grow in clusters. They retain osteogenic, chondrogenic, and adipogenic differentiation potential. We present 16 clinical cases of tendonitis and desmitis, treated with allogenic eSM-MSCs and autologous serum, and we also include their evaluation, treatment, and follow-up. The concerns associated with the use of autologous serum as a vehicle are related to a reduced immunogenic response after the administration of this therapeutic combination, as well as the pro-regenerative effects from the growth factors and immunoglobulins that are part of its constitution. Most of the cases (14/16) healed in 30 days and presented good outcomes. Treatment of tendon and ligament lesions with a mixture of eSM-MSCs and autologous serum appears to be a promising clinical option for this category of lesions in equine patients.

10.
Biomedicines ; 11(3)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36979779

RESUMO

Gastric cancer (GC) ranked as the fifth most incident cancer in 2020 and the third leading cause of cancer mortality. Surgical prevention and radio/chemotherapy are the main approaches used in GC treatment, and there is an urgent need to explore and discover innovative and effective drugs to better treat this disease. A new strategy arises with the use of repurposed drugs. Drug repurposing coupled with drug combination schemes has been gaining interest in the scientific community. The main objective of this project was to evaluate the therapeutic effects of alternative drugs in GC. For that, three GC cell lines (AGS, MKN28, and MKN45) were used and characterized. Cell viability assays were performed with the reference drug 5-fluororacil (5-FU) and three repurposed drugs: natamycin, nitazoxanide, and benztropine. Nitazoxanide displayed the best results, being active in all GC cells. Further, 5-FU and nitazoxanide in combination were tested in MKN28 GC cells, and the results obtained showed that nitazoxanide alone was the most promising drug for GC therapy. This work demonstrated that the repurposing of drugs as single agents has the ability to decrease GC cell viability in a concentration-dependent manner.

11.
Molecules ; 28(3)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36770899

RESUMO

This work describes the design, sustainable synthesis, evaluation of electrochemical and biological properties against HepG2 cell lines, and AChE enzymes of different substituted derivatives of 1,4- and 1,2-naphthoquinones (NQ). A microwave-assisted protocol was optimized with success for the synthesis of the 2-substituted-1,4-NQ series and extended to the 4-substituted-1,2-NQ family, providing an alternative and more sustainable approach to the synthesis of naphthoquinones. The electrochemical properties were studied by cyclic voltammetry, and the redox potentials related to the molecular structural characteristics and the biological properties. Compounds were tested for their potential anti-cancer activity against a hepatocellular carcinoma cell line, HepG2, using MTT assay, and 1,2-NQ derivatives were found to be more active than their 1,4-NQ homologues (3a-f), with the highest cytotoxic potential found for compound 4a (EC50 = 3 µM). The same trend was found for the inhibitory action against acetylcholinesterase, with 1,2-NQ derivatives showing higher inhibition50µM than their 1,4-NQ homologues, with 4h being the most potent compound (Inhibition50µM = 85%). Docking studies were performed for the 1,2-NQ derivatives with the highest inhibitions, showing dual binding interactions with both CAS and PAS sites, while the less active 1,4-NQ derivatives showed interactions with PAS and the mid-gorge region.


Assuntos
Acetilcolinesterase , Naftoquinonas , Naftoquinonas/química , Linhagem Celular
12.
N Biotechnol ; 77: 176-184, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36563877

RESUMO

Lignin is the second most abundant natural polymer next to cellulose and by far the largest renewable source of aromatic compounds on the planet. Dye-decolourising peroxidases (DyPs) are biocatalysts with immense potential in lignocellulose biorefineries to valorize emerging lignin building blocks for environmentally friendly chemicals and materials. This work investigates the catalytic potential of the engineered PpDyP variant 6E10 for the oxidation of 24 syringyl, guaiacyl and hydroxybenzene lignin-phenolic derivatives. Variant 6E10 exhibited up to 100-fold higher oxidation rates at pH 8 for all the tested phenolic substrates compared to the wild-type enzyme and other acidic DyPs described in the literature. The main products of reactions were dimeric isomers with molecular weights of (2 × MWsubstrate - 2 H). Their structure depends on the substitution pattern of the aromatic ring of substrates, i.e., of the coupling possibilities of the primarily formed radicals upon enzymatic oxidation. Among the dimers identified were syringaresinol, divanillin and diapocynin, important sources of structural scaffolds exploitable in medicinal chemistry, food additives and polymers.


Assuntos
Lignina , Peroxidase , Lignina/metabolismo , Oxirredutases , Peroxidases , Oxirredução , Fenóis
13.
Waste Manag Res ; 41(1): 235-247, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35894451

RESUMO

The end of life of pharmaceutical products through environmentally unsafe routes is a growing concern in our society. However, the studies reported so far, apart from being limited in number, do not reflect the current management practices for the end-of-life management of pharmaceuticals. Published work lacks an in-depth analysis in focusing on the pharmaceutical waste in households. The present work focused on (1) performing a state-of-the art overview to compare worldwide studies and the results and (2) implementing a comprehensive survey in Portugal (n = 454 respondents). The results showed that the delivery to pharmacies was used by the majority of the respondents (72%), indicating a good awareness of pharmaceutical waste management issues, when compared to the reviewed studies. Statistically significant variables for the destination of end-of-use pharmaceuticals include gender, age and distance from the residence to the pharmacy (p < 0.05). Most participants believe that educating the population on existing structures of medication and packaging management is of the utmost importance to improve the national managing system. This is the first study conducted in Portugal; it includes statistical analysis of the data and reflects on the practices that should be adopted to reduce incorrect pharmaceutical waste disposal. These findings call upon the strategies to strengthen the pharmaceutical waste management programme.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Humanos , Características da Família , Preparações Farmacêuticas , Portugal
14.
Pharmaceutics ; 14(12)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36559137

RESUMO

Notwithstanding the advances achieved in the last decades in the field of synthetic bone substitutes, the development of biodegradable 3D-printed scaffolds with ideal mechanical and biological properties remains an unattained challenge. In the present work, a new approach to produce synthetic bone grafts that mimic complex bone structure is explored. For the first time, three scaffolds of various composition, namely polycaprolactone (PCL), PCL/hydroxyapatite nanoparticles (HANp) and PCL/HANp/diacrylate poly(ethylene glycol) (PEGDA), were manufactured by extrusion. Following the production and characterisation of the scaffolds, an in vitro evaluation was carried out using human dental pulp stem/stromal cells (hDPSCs). Through the findings, it was possible to conclude that, in all groups, the scaffolds were successfully produced presenting networks of interconnected channels, adequate porosity for migration and proliferation of osteoblasts (approximately 50%). Furthermore, according to the in vitro analysis, all groups were considered non-cytotoxic in contact with the cells. Nevertheless, the group with PEGDA revealed hydrophilic properties (15.15° ± 4.06) and adequate mechanical performance (10.41 MPa ± 0.934) and demonstrated significantly higher cell viability than the other groups analysed. The scaffolds with PEGDA suggested an increase in cell adhesion and proliferation, thus are more appropriate for bone regeneration. To conclude, findings in this study demonstrated that PCL, HANp and PEGDA scaffolds may have promising effects on bone regeneration and might open new insights for 3D tissue substitutes.

15.
High Alt Med Biol ; 23(4): 301-312, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36036723

RESUMO

Kindlovits, Raquel, Alberto Mello da Silva Pereira, Ana Catarina Sousa, João Luís Viana,and Vitor Hugo Teixeira. Effects of acute and chronic exercise in hypoxia on cardiovascular and glycemic parameters in patients with type 2 diabetes: a systematic review. High Alt Med Biol. 23:301-312, 2022. Background: Exercise in hypoxia (EH, decreased oxygen availability) has been proposed as a potential therapeutic intervention to promote angiogenesis and improve glucose metabolism to a greater extent than exercise under normoxia (normal ambient air) in patients with type 2 diabetes (T2D). Currently, there are no studies that systematize the existent evidence. This study aims to systematically review the literature and qualitatively evaluate the effects of acute and chronic EH on cardiovascular and glycemic parameters in T2D patients. Methods: A structured search was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines until March 2021, in the MEDLINE/PubMed, Scopus, and Web of Science databases. The inclusion criteria were as follows: (1) randomized and nonrandomized trials, (2) in complication-free patients with T2D, (3) in which EH was compared with exercise in normoxia or with baseline data, and (4) published in English. Results: Six articles (64 subjects) met the inclusion criteria and were reviewed to data extraction. Four articles investigated the acute effect of EH (33 subjects), and two articles investigated the chronic effect of EH (31 subjects), ranging from 6 to 8 weeks. All studies used a cycle ergometer as exercise. Acute EH benefits insulin sensitivity, blood glucose, vascular endothelial growth factor, and metalloproteinase-9, while chronic EH benefits nitric oxide synthase in erythrocytes, but not brachial artery flow-mediated dilation. Conclusion: Acute EH improves glucose homeostasis in T2D patients, which was not seen with chronic EH. Both acute EH and chronic EH improve angiogenesis regulators, but not vascular function. Despite the putative benefits of EH in patients with T2D, the evidence is still scarce and further research is needed before recommendations can be provided.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicações , Fator A de Crescimento do Endotélio Vascular , Exercício Físico , Glicemia , Hipóxia
17.
ACS Appl Mater Interfaces ; 14(22): 25104-25114, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35621184

RESUMO

This study describes the preparation, characterization, and antimicrobial properties of novel hybrid biopolymer materials doped with bioactive silver(I) coordination polymers (bioCPs). Two new bioCPs, [Ag2(µ6-hfa)]n (1) and [Ag2(µ4-nda)(H2O)2]n (2), were assembled from Ag2O and homophthalic (H2hfa) or 2,6-naphthalenedicarboxylic (H2nda) acids as unexplored building blocks. Their structures feature 2D metal-organic and supramolecular networks with 3,6L64 or sql topology. Both compounds act as active antimicrobial agents for producing bioCP-doped biopolymer films based on epoxidized soybean oil acrylate (SBO) or potato starch (PS) as model biopolymer materials with a different rate of degradability and silver release. BioCPs and their hybrid biopolymer films (1@[SBO]n, 2@[SBO]n, 1@[PS]n, and 2@[PS]n) with a very low loading of coordination polymer (0.05-0.5 wt %) show remarkable antimicrobial activity against Staphylococcus aureus and Staphylococcus epidermidis (Gram-positive) and Escherichia coli and Pseudomonas aeruginosa (Gram-negative) bacteria. Biopolymer films also effectively impair the formation of bacterial biofilms, allowing total biofilm inhibition in several cases. By reporting on new bioCPs and biopolymer films obtained from renewable biofeedstocks (soybean oil and PS), this study blends highly important research directions and widens a limited antimicrobial application of bioCPs and derived functional materials. This research thus opens up the perspectives for designing hybrid biopolymer films with outstanding bioactivity against bacterial biofilms.


Assuntos
Anti-Infecciosos , Solanum tuberosum , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Biofilmes , Escherichia coli , Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana , Polímeros/química , Polímeros/farmacologia , Prata/química , Prata/farmacologia , Óleo de Soja , Staphylococcus epidermidis , Amido/farmacologia
18.
Int J Mol Sci ; 23(4)2022 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-35216432

RESUMO

Bone tissue engineering has been developed in the past decades, with the engineering of bone substitutes on the vanguard of this regenerative approach. Polycaprolactone-based scaffolds are fairly applied for bone regeneration, and several composites have been incorporated so as to improve the scaffolds' mechanical properties and tissue in-growth. In this study, hydroxyapatite is incorporated on polycaprolactone-based scaffolds at two different proportions, 80:20 and 60:40. Scaffolds are produced with two different blending methods, solvent casting and melt blending. The prepared composites are 3D printed through an extrusion-based technique and further investigated with regard to their chemical, thermal, morphological, and mechanical characteristics. In vitro cytocompatibility and osteogenic differentiation was also assessed with human dental pulp stem/stromal cells. The results show the melt-blending-derived scaffolds to present more promising mechanical properties, along with the incorporation of hydroxyapatite. The latter is also related to an increase in osteogenic activity and promotion. Overall, this study suggests polycaprolactone/hydroxyapatite scaffolds to be promising candidates for bone tissue engineering, particularly when produced by the MB method.


Assuntos
Osso e Ossos/efeitos dos fármacos , Durapatita/química , Durapatita/uso terapêutico , Poliésteres/química , Poliésteres/uso terapêutico , Solventes/química , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/química , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Teste de Materiais/métodos , Osteogênese/efeitos dos fármacos , Porosidade , Impressão Tridimensional , Engenharia Tecidual/métodos
19.
Porto; s.n; 20220216. il., tab..
Tese em Português | BDENF | ID: biblio-1379656

RESUMO

Enquadramento: As quedas nas pessoas idosas representam o principal motivo de admissão ao serviço de urgência, de incapacidade, de institucionalização e morte. Face ao impacte que a queda pode ter na saúde e qualidade de vida da pessoa idosa e aos elevados custos que lhe estão associados, vários programas de intervenção têm sido implementados, visando a sua prevenção no contexto comunitário. O objetivo desta pesquisa foi identificar a evidência produzida sobre os programas/as intervenções que se têm revelado eficazes na prevenção de quedas, em idosos com 75 e mais anos, não institucionalizados. Metodologia: Foi realizada uma revisão sistemática da literatura, conduzida segundo as orientações do grupo Cochrane. Para esta pesquisa foram considerados estudos que cumprissem os seguintes critérios: i) participantes com idade ≥ 75 anos, residentes na comunidade, com capacidade cognitiva e independência nas AVD´s, ii) intervenções únicas ou multifacetadas dirigidas à prevenção das quedas, iii) estudos experimentais, quasi-experimentais (com grupo controlo) e RSL. A pesquisa foi realizada nas bases de dados EBSCO HOST, SCOPUS e Web of Science, entre abril e maio de 2021. Foram considerados ainda estudos em português, inglês e espanhol, publicados após 2015. Para a apresentação da seleção dos estudos recorreu-se ao fluxograma PRISMA. A análise dos estudos, a extração dos dados e a avaliação da qualidade metodológica foi realizada por dois revisores independentes. Resultados: Dos 416 estudos inicialmente identificados, com base nos critérios pré-definidos e após análise dos mesmos, nenhum estudo foi selecionado. Conclusão: A não identificação de estudos primários que respondam à questão orientadora da revisão é um achado relevante para a comunidade científica, pois indicia lacunas no conhecimento sobre a problemática no grupo populacional em estudo. Para uma tomada de decisão baseada na melhor evidência, emerge a necessidade de estudos de desenho experimental, para responder a questões sobre eficácia de uma intervenção terapêutica.


Framework: Falls in the elderly represent the main reason for admission to the emergency service, disability, institutionalization and death. Given the impact that a fall can have on the health and quality of life of the elderly and the high costs associated with it, several intervention programs have been implemented, aiming at its prevention in the community context. The objective of this research was to identify the evidence produced about the programs/interventions that have proven to be effective in preventing falls, in non-institutionalized elderly people aged 75 and over. Methodology: A systematic review of the literature was carried out, conducted according to the guidelines of the Cochrane group. For this research, studies that met the following criteria were considered: i) participants aged ≥ 75 years, living in the community, with cognitive capacity and independence in ADLs, ii) single or multifaceted interventions aimed at preventing falls, iii) studies experimental, quasi-experimental (with control group) and RSL. The research was carried out in the EBSCO HOST, SCOPUS and Web of Science databases, between April and May 2021. Studies in Portuguese, English and Spanish, published after 2015 were also considered. PRISMA flowchart. Study analysis, data extraction and assessment of methodological quality were performed by two independent reviewers. Results: Of the 416 studies initially identified, based on predefined criteria and after their analysis, no study was selected. Conclusion: The non-identification of primary studies that answer the guiding question of the review is a relevant finding for the scientific community, as it indicates gaps in knowledge about the problem in the population group under study. For decision-making based on the best evidence, the need for experimental design studies to answer questions about the effectiveness of a therapeutic intervention emerges.


Assuntos
Humanos , Idoso , Idoso de 80 Anos ou mais , Acidentes por Quedas
20.
Metabolites ; 12(1)2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35050193

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by deficits in social interaction, impaired communication, and repetitive behaviors. ASD presents a 3:1 ratio of diagnosed boys and girls, raising the question regarding sexual dimorphic mechanisms underlying ASD symptoms, and their molecular basis. Here, we performed in vivo proton magnetic resonance spectroscopy in juvenile male and female Tsc2+/- mice (an established genetic animal model of ASD). Moreover, behavior and ultrasonic vocalizations during social and repetitive tasks were analyzed. We found significant sexual dimorphisms in the levels of metabolites in the hippocampus and prefrontal cortex. Further, we observed that female mutant animals had a differential social behavior and presented an increase in repetitive behavior. Importantly, while mutant females displayed a more simplified communication during social tasks, mutant males exhibited a similar less complex vocal repertoire but during repetitive tasks. These results hint toward sex-dependent alterations in molecular and metabolic pathways, which can lead to the sexual dimorphic behaviors and communication observed in social and repetitive environments.

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