1,765 research outputs found
Peritoneal Dialysis in Diabetics: There Is Room for More
End stage renal disease diabetic patients suffer from worse clinical outcomes under dialysis-independently of modality. Peritoneal dialysis offers them the advantages of home therapy while sparing their frail vascular capital and preserving residual renal function. Other benefits and potential risks deserve discussion. Predialysis intervention with early nephrology referral, patient education, and multidisciplinary support are recommended. Skilled and updated peritoneal dialysis protocols must be prescribed to assure better survival. Optimized volume control, glucose-sparing peritoneal dialysis regimens, and elective use of icodextrin are key therapy strategies. Nutritional evaluation and support, preferential use of low-glucose degradation products solutions, and prescription of renin-angiotensin-aldosterone system acting drugs should also be part of the panel to improve diabetic care under peritoneal dialysis
A dynamic multi-criteria decision-making model for the maintenance planning of reinforced concrete structures
Decision-making is essential in buildings management process playing a decisive role in the maintenance planning design. Multi-Criteria Decision Making (MCDM) methods can be applied as a support tool to fulfil a set of requirements that arise during the scheduling of maintenance activities of these structures. The Analytic Hierarchy Process (AHP) is a broadly recognised methodology applied to model subjectively decision problems based on multi attributes analysis. This paper applies the AHP method under an objective approach, where the weight assignments are stochastically calculated instead of defining it based on the judgement of experts. The main objective of this study is to propose a dynamic decision model based on AHP for the maintenance planning of reinforced concrete structures under corrosion risk. This methodology provides the best maintenance alternative (inspection/repair) to be performed in these structures for a given intervention time. The best solution for the intervention is chosen regarding the Global Priority Vector of the final pairwise comparison matrix. After an illustrative application, the new dynamic decision model developed proven be a helpful tool for decisions-making regarding the most suitable intervention alternative within the maintenance planning of these structures.publishe
Comportamento de pilares de betão armado sujeitos a ações monotónicas e cíclicas
Para a avaliação da resposta de estruturas de edifícios de betão armado sujeitas à ação sísmica é importante definir um conjunto de parâmetros característicos do comportamento local dos elementos de betão armado, nomeadamente o deslocamento de cedência e o deslocamento último. Nas últimas décadas foram dados importantes passos na caracterização do comportamento cíclico de pilares de betão armado, mas persistem ainda algumas questões em aberto, nomeadamente no que se refere às diferenças entre a resposta a solicitações monotónicas e cíclicas, e para os carregamentos cíclicos entre solicitações uniaxiais e biaxiais. Por outro lado, é reconhecido que em elementos de betão armado carregados axialmente e sujeitos a esforços de flexão biaxiais se observa um agravamento da degradação de rigidez e a sua ductilidade é reduzida.
O presente estudo enquadra-se numa vasta campanha de ensaios realizada sobre pilares retangulares de betão armado sujeitos à flexão cíclica, uniaxial e biaxial. Neste artigo é apresentada uma parte dos resultados e conclusões desse trabalho experimental, focando-se num conjunto de ensaios realizados em 6 pilares retangulares (3 ensaios monotónicos uniaxiais e 3 ensaios cíclicos com lei de deslocamentos impostos oblíqua com ângulos de 30o, 45o e 60o). É realizada uma análise dos resultados em termos de comportamento global dos pilares, da evolução do dano, das componentes de deformação e da dissipação de energia
The impact of an 8-week Pilates-based physical training program on functional mobility: Data from a septuagenarian group
Study aim: This study aimed to evaluate the effects of a Pilates-based training program on functional mobility and strength in community-dwelling adults over 70 years old. Material and methods: Twenty community-dwelling elderly subjects were recruited and randomly assigned to control (C = 10) or Pilates training (PT = 10) groups for 8 weeks (2 times/week). Anthropometric, strength, cardiorespiratory fitness, functional mobility, and static and dynamic balance parameters were assessed before and after the intervention. Results: The PT group had higher values of lower limb strength (p = 0.013 d = 0.56) and 6-minute walking test distance (p = 0.04; d = 0.45) than the C group. The PT group also had differences in one leg stance duration and decrease in the Timed Up and Go test. We also observed a positive correlation between muscle strength and cardiorespiratory fitness (p < 0.01, r = 0.62), cardiorespiratory fitness and one leg stance, eyes closed, right and left leg (p = 0.04, r = 0.45; p = 0.05, r = 0.45, respectively). Conclusions: Eight weeks of Pilates-based physical training induced improvements in skeletal muscle strength and functional mobility of community-dwelling septuagenarians
Unravelling the path to create a cell sheet-based model of skin scar-like tissue
Regardless of the advances in understanding the mechanisms and the pathophysiology behind skin deformities, scaring continues to be an unsolved clinical problem. The underlying wound healing process involves a series of key cells which play different key roles. Fibroblasts are known to suffer the influence of local biochemical (e.g TGF-B1) and biomechanical signaling upon a wound scenario leading to a phenotypical change into myofibroblasts. The latter enhance immature extracellular matrix (ECM) synthesis and generate tensional forces that leads to ECM reorganization. Certain skin pathologies (e.g hypertrophic scars) rise from a dysfunction of this underlying regulatory mechanism which in turn drives myofibroblast persistence in the wound. When trying to study the mechanisms behind scarring human ex vivo samples are many times scarce and most of the current in vitro systems rely on standard 2D cultures of keloid/hypertrophic scar fibroblasts. Taking all of this into consideration we propose the use of cell sheet technology to create an in vitro 3D scar model. Herein we report the effect of TGF-B1 in human dermal fibroblast cell sheets as the first step to attain cell sheets with a myofibroblast-like phenotype in which cells are embedded in a scar-like ECM. To further strengthen our concept we performed the stacking of pre-formed cell sheets generating a cohesive 3D scar-like tissue.
Human dermal fibroblast (hDFbs) cell sheets were produced as previously described1, and stimulated with TGF-B1 (10ng/ml) over 7, 14 and 21 days. Following phenotype and ECM characterization, cell sheets were stacked in order to obtain a 3D structure composed of 2 or 3 cell-sheets. The analysis of key genes (q-PCR) and proteins (Western blot and immunocytochemistry) showed that hDFbs cell sheets, when stimulated with TGF-B1 present an increased expression of a-SMA, fibronectin (FN) ED- A and FN ED-B, characteristic of a myofibroblast-like phenotype. When looking into the expression of scar ECM-associated proteins, hDFbs cell sheets obtained in the presence of TGF-B1 produced higher amounts of fibronectin and collagen I. Stable 3D constructs with a noticeable level of integration after a total of 21 days of culture, were further created upon stacking of the cell sheets obtained after 7days of culture in the presence of TGF-B1.
In conclusion, this work suggested that it is possible to promote the secretion of scar-like ECM in hDFbs cell sheets due to phenotypic changes into myofibroblast-like cells when stimulated with TGF-B1. Cohesive 3D scar-like tissue structures were obtained which opens the possibility to develop a highly accurate in vitro 3D scar model to study underlying cellular mechanisms involved in the wound healing deregulation. Grant IF/00945/2014 funded by FCT/MCTES, Project “NORTE-08-5369-FSE-000044”, funded by Programa Operacional Norte 2020 Fundo Social Europeu, and GENE2SKIN
Twinning Project, Horizon 2020, funded by the European Commissioninfo:eu-repo/semantics/publishedVersio
In vitro 3D cell sheet-based model for unraveling scar pathophysiology
Fibroblasts are key players in the scarring process. In hypertrophic scars, fibroblasts suffer phenotypical changes into myofibroblasts persisting in the wound under the influence of local biochemical (TGFb1) and biomechanical signaling leading to enhanced immature extracellular matrix (ECM) synthesis. Benchtop models of hypertrophic scars rely on scarce human ex vivo samples or standard 2D cultures of hypertrophic scar fibroblasts. We therefore propose the use of human dermal fibroblast cell sheets (hDFbsCS) as the first step to attain cell sheets with a myofibroblast-like phenotype to generate cohesive in vitro 3D scar-like tissues. hDFbsCS were produced as previously described (Cerqueira, 2014), and stimulated with TGFb1 up to 21 days. Following phenotype and ECM characterization, 3 hDFbsCS were stacked to obtain a 3D structure. Gene and protein analysis showed that upon TGFb1 stimulation, hDFbsCS present a higher expression of aSMA, fibronectin EDA and EDB, characteristic of amyofibroblast-like phenotype. Regarding the expression of scar ECM-associated proteins, TGFb1 stimulated hDFbsCS produced increased fibronectin and collagen I. Upon stacking of hDFbsCS obtained after 7 days of culture in the presence of TGFb1, stable and integrated 3D constructs were obtained. This work suggests that it is possible to create cohesive 3D scar-like tissue structures from hDFbsCS opening the possibility to develop in vitro 3D scar models to study wound healing deregulation pathophysiology.
Acknowledgments: Grant IF.00945.2014 and SFRH.BD. 119756.2016 (FCT MCTES), NORTE.08.5369.FSE.000044 (funded by Programa Operacional Norte 2020 Fundo Social Europeu), GENE2SKIN Twinning Project, Horizon 2020 (European Commission).Grant IF.00945.2014 and SFRH.BD.119756.2016 (FCT_MCTES), NORTE.08.5369.FSE.000044 (funded by Programa_Operacional_Norte_2020 Fundo Social Europeu), GENE2SKIN Twinning Project, Horizon_2020 (European Commission).info:eu-repo/semantics/publishedVersio
Evaluation of Respiratory, Genotoxic and Cytotoxic Effects from Occupational Exposure to Typography Activities
This cross-sectional study was structured to allow the evaluation of the respiratory, genotoxic, and cytotoxic effects of occupational exposure to products resulting from the activity of printers in typographies and, to determine the risk of genotoxicity associated with such exposure. This study comprised 69 subjects, 25 individuals occupationally exposed to the products of typographies (study group), and 44 individuals non-exposed to the environment studied (reference group). The frequency of micronucleated cells and other nuclear anomalies (binucleated, karyolitic, pyknotic, and karyorrhectic cells) in the oral epithelia of each subject were analyzed. The frequency of micronucleated cells was significantly higher in the study group when compared to the reference one (12.96 MN/2000 cells vs. 4 MN/2000 cells, respectively). Occupational exposure to products of typography is a risk factor for the occurrence of micronucleated cells in the study group (RR = 3.2; 95% CI, 2.7–3.9; p < 0.001). The results of the spirometry test did not reveal significant respiratory effects between the reference and study groups.FUNDING: This work was financially supported by Azores DRCT Plurianual Funding (M1.1.A/ Func.UI&D/010/2021-2024) and by the Fundo Regional da Ciência (Regional Government of the Azores) (Diana Linhares post-doc fellowship-M3.1.a/F/004/2018).info:eu-repo/semantics/publishedVersio
Hidden Consequence of Active Local Lorentz Invariance
In this paper we investigate a hidden consequence of the hypothesis that
Lagrangians and field equations must be invariant under active local Lorentz
transformations. We show that this hypothesis implies in an equivalence between
spacetime structures with several curvature and torsion possibilities.Comment: Some misprints appearing in the published version have been correcte
Impact of an Operating Room Nurse Preoperative Dialogue on Anxiety, Satisfaction and Early Postoperative Outcomes in Patients Undergoing Major Visceral Surgery-A Single Center, Open-Label, Randomized Controlled Trial.
Anxiety is common before surgery and known to negatively impact recovery from surgery. The aim of this study was to evaluate the impact of a preoperative nurse dialogue on a patient's anxiety, satisfaction and early postoperative outcomes.
This 1:1 randomized controlled trial compared patients undergoing major visceral surgery after a semistructured preoperative nurse dialogue (interventional group: IG) to a control group (CG) without nursing intervention prior to surgery. Anxiety was measured with the autoevaluation scale State-Trait Anxiety Inventory (STAI, Y-form) pre and postoperatively. The European Organization for Research and Treatment of Cancer (EORTC) In-Patsat32 questionnaire was used to assess patient satisfaction at discharge. Further outcomes included postoperative pain (visual analogue scale: VAS 0-10), postoperative nausea and vomiting (PONV), opiate consumption and length of stay (LOS).
Over a period of 6 months, 35 participants were randomized to either group with no drop-out or loss to follow-up (total n = 70). The median score of preoperative anxiety was 40 (IQR 33-55) in the IG vs. 61 (IQR 52-68) in the CG (p &lt; 0.001). Postoperative anxiety levels were comparable 34 (IQR 25-46) vs. 32 (IQR 25-44) for IG and CG, respectively (p = 0.579). The IG did not present higher overall satisfaction (90 ± 15 vs. 82.9 ± 16, p = 0.057), and pain at Day 2 was similar (1.3 ± 1.7 vs. 2 ± 1.9, p = 0.077), while opiate consumption, PONV levels and LOS were comparable.
A preoperative dialogue with a patient-centered approach helped to reduce preoperative anxiety in patients undergoing major visceral surgery
Rigorous Formulation of Duality in Gravitational Theories
In this paper we evince a rigorous formulation of duality in gravitational
theories where an Einstein like equation is valid, by providing the conditions
under which the Hodge duals (with respect to the metric tensor g) of T^a and
R_b^a may be considered as the torsion and curvature 2-forms associated with a
connection D', part of a Riemann-Cartan structure (M,g',D'), in the cases g =
g' and g does not equal g', once T^a and R_b^a are the torsion and curvature
2-forms associated with a connection D part of a Riemann-Cartan structure
(M,g,D). A new form for the Einstein equation involving the dual of the Riemann
tensor of D is also provided, and the result is compared with others appearing
in the literature.Comment: 15 page
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