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1.
Artigo em Inglês | MEDLINE | ID: mdl-36673918

RESUMO

The key factor in moving towards a more sustainable travel model is based on improving mobility, especially in rural areas that share territorial dynamics with urban areas and are connected by a daily flow of inhabitants. The purpose of this article is to carry out a diagnosis of the daily mobility patterns of the inhabitants of a number of rural municipalities, with the aim of promoting sustainability and mitigating the phenomenon of territorial depopulation in future local planning policies. The research methodology is based on the use of revealed preference surveys together with accessibility analysis using GIS tools, allowing for an in-depth knowledge of the mobility patterns of the municipalities in the area under analysis. In this respect, the reference parameters in terms of territorial accessibility are determined by applying the network analysis procedure to basic public services. The results reflect the existence of an unbalanced modal split with a preponderance of private vehicle use (regardless of the destination or the reason for the journey). In addition, a very weak inter-municipal connection dynamic is observed. There is a knowledge gap in the verification of the long-term suitability of sustainable measures in rural areas implemented after the development of mobility plans (in order to assess their effectiveness).


Assuntos
População Rural , Viagem , Humanos , Cidades , Inquéritos e Questionários , Demografia
2.
Gels ; 8(11)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36354636

RESUMO

Background: Angiogenesis is a crucial process in physiological maintenance and tissue regeneration. To understand the contribution of angiogenesis, it is essential to replicate this process in an environment that reproduces the biochemical and physical properties which are largely governed by the extracellular matrix (ECM). We investigated vascularization in cardiac left ventricular ECM hydrogels to mimic post-myocardial repair. We set out to assess and compare different destructive and non-destructive methods, optical as well as non-optical, to visualize angiogenesis and associated matrix remodeling in myocardial ECM hydrogels. Methods: A total of 100,000, 300,000, and 600,000 Human Pulmonary Microvascular Endothelial Cells (HPMEC) were seeded in left ventricular cardiac ECM hydrogel in 48-well plates. After 1, 7, and 14 days of culture, the HPMEC were imaged by inverted fluorescence microscopy and 3D confocal laser scanning microscopy (Zeiss Cell Discoverer 7). In addition, cell-seeded ECM hydrogels were scanned by optical coherence tomography (OCT). Fixed and paraffin-embedded gels were thin-sectioned and assessed for ECM components via H&E, picrosirius red histochemical staining, and immunostaining for collagen type I. ImageJ-based densitometry was used to quantify vascular-like networks and GraphPad was used for statistical analyses. Results: Qualitative analyses were realized through fluoromicrographs obtained by the confocal laser scanning microscope which allowed us to visualize the extensive vascular-like networks that readily appeared at all seeding densities. Quantification of networks was only possible using fluoromicrographs from inverted microscopy. These showed that, after three days, the number of master junctions was seeding density-dependent. The resolution of optical coherence tomography was too low to distinguish between signals caused by the ECM and cells or networks, yet it did show that gels, irrespective of cells, were heterogeneous. Interestingly, (immuno)histochemistry could clearly distinguish between the cast cardiac-derived matrix and newly deposited ECM in the hydrogels. The H&E staining corroborated the presence of vascular-like network structures, albeit that sectioning inevitably led to the loss of 3D structure. Conclusions: Except for OCT, all methods had complementary merit and generated qualitative and quantitative data that allowed us to understand vascular network formation in organ-derived ECM hydrogels.

3.
Gels ; 8(9)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36135247

RESUMO

The extracellular matrix (ECM) is a three-dimensional, acellular scaffold of living tissues. Incorporating the ECM into cell culture models is a goal of cell biology studies and requires biocompatible materials that can mimic the ECM. Among such materials are hydrogels: polymeric networks that derive most of their mass from water. With the tuning of their properties, these polymer networks can resemble living tissues. The microarchitectural properties of hydrogels, such as porosity, pore size, fiber length, and surface topology can determine cell plasticity. The adequate characterization of these parameters requires reliable and reproducible methods. However, most methods were historically standardized using other biological specimens, such as 2D cell cultures, biopsies, or even animal models. Therefore, their translation comes with technical limitations when applied to hydrogel-based cell culture systems. In our current work, we have reviewed the most common techniques employed in the characterization of hydrogel microarchitectures. Our review provides a concise description of the underlying principles of each method and summarizes the collective data obtained from cell-free and cell-loaded hydrogels. The advantages and limitations of each technique are discussed, and comparisons are made. The information presented in our current work will be of interest to researchers who employ hydrogels as platforms for cell culture, 3D bioprinting, and other fields within hydrogel-based research.

4.
Bioengineering (Basel) ; 9(8)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35892753

RESUMO

Adipose tissue-derived stromal cells (ASCs) are of interest in tissue engineering and regenerative medicine (TERM) due to their easy acquisition, multipotency, and secretion of a host of factors that promote regeneration. Retention of ASCs in or around lesions is poor following direct administration. Therefore, for TERM applications, ASCs can be 'immobilized' via their incorporation into hydrogels such as gelatine methacryloyl (GelMA). Tweaking GelMA concentration is a common approach to approximate the mechanical properties found in organs or tissues that need repair. Distinct hydrogel mechanics influence the ability of a cell to spread, migrate, proliferate, and secrete trophic factors. Mesenchymal cells such as ASCs are potent remodellers of the extracellular matrix (ECM). Not only do ASCs deposit components, they also secrete matrix metalloproteases (MMPs) which degrade ECM. In this work, we investigated if GelMA polymer concentration influenced the expression of active MMPs by ASCs. In addition, MMPs' presence was interrogated with regard to ASCs morphology and changes in hydrogel ultrastructure. For this, immortalised ASCs were embedded in 5%, 10%, and 15% (w/v) GelMA hydrogels, photopolymerised and cultured for 14 d. Zymography in situ indicated that MMPs had a variable, hydrogel concentration-dependent influence on ASCs-secreted MMPs. In 5% GelMA, ASCs showed a high and sustained expression of MMPs, while, in 10% and 15% GelMA, such expression was almost null. ASCs morphology based on F-actin staining showed that increasing GelMA concentrations inhibit their spreading. Scanning electron microscopy (SEM) showed that hydrogel ultrastructure in terms of pore density, pore size, and percentage porosity were not consistently influenced by cells. Interestingly, changes in ultrastructural parameters were detected also in cell-free materials, albeit without a clear trend. We conclude that hydrogel concentration and its underlying mechanics influenced MMP expression by ASCs. The exact MMPs that respond to these mechanical cues should be defined in follow-up experiments.

5.
Biomater Adv ; 139: 212967, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35882126

RESUMO

Dermal wound healing relies on the properties of the extracellular matrix (ECM). Thus, hydrogels that replicate skin ECM have reached clinical application. After a dermal injury, a transient, biodegradable fibrin clot is instrumental in wound healing. Human plasma, and its main constituent, fibrin would make a suitable biomaterial for improving wound healing and processed as hydrogels albeit with limited mechanical strength. To overcome this, plasma-agarose (PA) composite hydrogels have been developed and used to prepare diverse bioengineered tissues. To date, little is known about the influence of variable agarose concentrations on the viscoelastic properties of PA hydrogels and their correlation to cell biology. This study reports the characterization of the viscoelastic properties of different concentrations of agarose in PA hydrogels: 0 %, 0.5 %, 1 %, 1.5 %, and 2 % (w/v), and their influence on the cell number and mitochondrial activity of human dermal fibroblasts. Results show that agarose addition increased the stiffness, relaxation time constants 1 (τ1) and 2 (τ2), and fiber diameter, whereas the porosity decreased. Changes in cell metabolism occurred at the early stages of culturing and correlated to the displacement of fast (τ1) and intermediate (τ2) Maxwell elements. Fibroblasts seeded in low PA concentrations spread faster during 14 d than cells cultured in higher agarose concentrations. Collectively, these results confirm that PA viscoelasticity and hydrogel architecture strongly influenced cell behavior. Therefore, viscoelasticity is a key parameter in the design of PA-based implants.


Assuntos
Hidrogéis , Engenharia Tecidual , Fibrina , Fibroblastos/metabolismo , Humanos , Hidrogéis/farmacologia , Sefarose , Engenharia Tecidual/métodos
6.
PLoS One ; 16(11): e0246707, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34739494

RESUMO

Glycogen-specific kinase (GSK3ß) is an integral regulator of the Wnt signalling pathway as well as many other diverse signalling pathways and processes. Dys-regulation of GSK3ß is implicated in many different pathologies, including neurodegenerative disorders as well as many different tumour types. In the context of tumour development, GSK3ß has been shown to play both oncogenic and tumour suppressor roles, depending upon tissue, signalling environment or disease progression. Although multiple substrates of the GSK3ß kinase have been identified, the wider protein networks within which GSK3ß participates are not well known, and the consequences of these interactions not well understood. In this study, LC-MS/MS expression analysis was performed using knockout GSK3ß colorectal cancer cells and isogenic controls in colorectal cancer cell lines carrying dominant stabilizing mutations of ß-catenin. Consistent with the role of GSK3ß, we found that ß-catenin levels and canonical Wnt activity are unaffected by knockout of GSK3ß and therefore used this knockout cell model to identify other processes in which GSK3ß is implicated. Quantitative proteomic analysis revealed perturbation of proteins involved in cell-cell adhesion, and we characterized the phenotype and altered proteomic profiles associated with this. We also characterized the perturbation of metabolic pathways resulting from GSK3ß knockout and identified defects in glycogen metabolism. In summary, using a precision colorectal cancer cell-line knockout model with constitutively activated ß-catenin we identified several of the diverse pathways and processes associated with GSK3ß function.


Assuntos
Adesão Celular/genética , Neoplasias Colorretais/genética , Glicogênio Sintase Quinase 3 beta/genética , Redes e Vias Metabólicas/genética , Via de Sinalização Wnt/fisiologia , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Proteômica
7.
Polymers (Basel) ; 13(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34578013

RESUMO

The proteins and polysaccharides of the extracellular matrix (ECM) provide architectural support as well as biochemical and biophysical instruction to cells. Decellularized, ECM hydrogels replicate in vivo functions. The ECM's elasticity and water retention renders it viscoelastic. In this study, we compared the viscoelastic properties of ECM hydrogels derived from the skin, lung and (cardiac) left ventricle and mathematically modelled these data with a generalized Maxwell model. ECM hydrogels from the skin, lung and cardiac left ventricle (LV) were subjected to a stress relaxation test under uniaxial low-load compression at a 20%/s strain rate and the viscoelasticity determined. Stress relaxation data were modelled according to Maxwell. Physical data were compared with protein and sulfated GAGs composition and ultrastructure SEM. We show that the skin-ECM relaxed faster and had a lower elastic modulus than the lung-ECM and the LV-ECM. The skin-ECM had two Maxwell elements, the lung-ECM and the LV-ECM had three. The skin-ECM had a higher number of sulfated GAGs, and a highly porous surface, while both the LV-ECM and the lung-ECM had homogenous surfaces with localized porous regions. Our results show that the elasticity of ECM hydrogels, but also their viscoelastic relaxation and gelling behavior, was organ dependent. Part of these physical features correlated with their biochemical composition and ultrastructure.

8.
Int J Mol Sci ; 22(18)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34576318

RESUMO

The extracellular matrix provides mechanical cues to cells within it, not just in terms of stiffness (elasticity) but also time-dependent responses to deformation (viscoelasticity). In this work, we determined the viscoelastic transformation of gelatine methacryloyl (GelMA) hydrogels caused by adipose tissue-derived stromal cells (ASCs) through mathematical modelling. GelMA-ASCs combination is of interest to model stem cell-driven repair and to understand cell-biomaterial interactions in 3D environments. Immortalised human ASCs were embedded in 5%, 10%, and 15% (w/v) GelMA hydrogels and evaluated for 14 d. GelMA had a concentration-dependent increase in stiffness, but cells decreased this stiffness over time, across concentrations. Viscoelastic changes in terms of stress relaxation increased progressively in 5% GelMA, while mathematical Maxwell analysis showed that the relative importance (Ri) of the fastest Maxwell elements increased proportionally. The 10% GelMA only showed differences at 7 d. In contrast, ASCs in 15% GelMA caused slower stress relaxation, increasing the Ri of the slowest Maxwell element. We conclude that GelMA concentration influenced the stiffness and number of Maxwell elements. ASCs changed the percentage stress relaxation and Ri of Maxwell elements transforming hydrogel viscoelasticity into a more fluid environment over time. Overall, 5% GelMA induced the most favourable ASC response.


Assuntos
Tecido Adiposo/metabolismo , Células Estromais/metabolismo , Materiais Biocompatíveis/química , Sobrevivência Celular/fisiologia , Módulo de Elasticidade/fisiologia , Matriz Extracelular/metabolismo , Humanos
9.
Materials (Basel) ; 14(11)2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34198787

RESUMO

Reconstruction of bile ducts damaged remains a vexing medical problem. Surgeons have few options when it comes to a long segment reconstruction of the bile duct. Biological scaffolds of decellularized biliary origin may offer an approach to support the replace of bile ducts. Our objective was to obtain an extracellular matrix scaffold derived from porcine extrahepatic bile ducts (dECM-BD) and to analyze its biological and biochemical properties. The efficiency of the tailored perfusion decellularization process was assessed through histology stainings. Results from 4'-6-diamidino-2-phenylindole (DAPI), Hematoxylin and Eosin (H&E) stainings, and deoxyribonucleic acid (DNA) quantification showed proper extracellular matrix (ECM) decellularization with an effectiveness of 98%. Immunohistochemistry results indicate an effective decrease in immunogenic marker as human leukocyte antigens (HLA-A) and Cytokeratin 7 (CK7) proteins. The ECM of the bile duct was preserved according to Masson and Herovici stainings. Data derived from scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) showed the preservation of the dECM-BD hierarchical structures. Cytotoxicity of dECM-BD was null, with cells able to infiltrate the scaffold. In this work, we standardized a decellularization method that allows one to obtain a natural bile duct scaffold with hierarchical ultrastructure preservation and adequate cytocompatibility.

10.
Mater Sci Eng C Mater Biol Appl ; 123: 112009, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33812628

RESUMO

Different bioinks have been used to produce cell-laden alginate-based hydrogel constructs for cell replacement therapy but some of these approaches suffer from issues with print quality, long-term mechanical instability, and bioincompatibility. In this study, new alginate-based bioinks were developed to produce cell-laden grid-shaped hydrogel constructs with stable integrity and immunomodulating capacity. Integrity and printability were improved by including the co-block-polymer Pluronic F127 in alginate solutions. To reduce inflammatory responses, pectin with a low degree of methylation was included and tested for inhibition of Toll-Like Receptor 2/1 (TLR2/1) dimerization and activation and tissue responses under the skin of mice. The viscoelastic properties of alginate-Pluronic constructs were unaffected by pectin incorporation. The tested pectin protected printed insulin-producing MIN6 cells from inflammatory stress as evidenced by higher numbers of surviving cells within the pectin-containing construct following exposure to a cocktail of the pro-inflammatory cytokines namely, IL-1ß, IFN-γ, and TNF-α. The results suggested that the cell-laden construct bioprinted with pectin-alginate-Pluronic bioink reduced tissue responses via inhibiting TLR2/1 and support insulin-producing ß-cell survival under inflammatory stress. Our study provides a potential novel strategy to improve long-term survival of pancreatic islet grafts for Type 1 Diabetes (T1D) treatment.


Assuntos
Bioimpressão , Insulinas , Alginatos , Animais , Camundongos , Pectinas , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais
11.
Mol Genet Metab ; 128(1-2): 129-136, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31378569

RESUMO

Late onset Pompe disease (LOPD) is a genetic disorder characterized by slowly progressive skeletal and respiratory muscle weakness. Symptomatic patients are treated with enzyme replacement therapy (ERT) with alglucosidase alpha (rhGAA). Although most of ERT treated patients develop antibodies against rhGAA, their influence on clinical progression is not completely known. We studied the impact of anti-rhGAA antibodies on clinical progression of 25 ERT treated patients. We evaluated patients at visit 0 and, after 1 year, at visit 1. We performed several muscle function tests, conventional spirometry and quantitative muscle MRI (qMRI) using 3-point Dixon analysis of thigh muscles at both visits. We also obtained serum samples at both visits and anti-rhGAA antibodies were quantified using ELISA. Antibody titers higher than 1:200 were identified in 18 patients (72%) of our cohort. Seven patients (28%) did not develop antibodies (0 to <1:200), 17 patients (68%) developed low to intermediate titers (1:200 to <1:31,200) and 1 patient (4%) developed high titers (>1:31,200). We analyzed the effect of low and intermediate antibody titers in clinical and radiological progression. There were no differences between the results of muscle function tests, spirometry or fat fraction analyzed using qMRI between patients with and without antibodies groups at baseline. Moreover, antibody titers did not influence muscle function test, spirometry results or qMRI results at year 1 visit. Most of the LOPD patients developed antibodies against ERT that persisted over time at low or intermediate levels. However, antibodies at these low and intermediate titers might not influence clinical response to the drug.


Assuntos
Anticorpos/sangue , Terapia de Reposição de Enzimas , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Transtornos de Início Tardio/tratamento farmacológico , alfa-Glucosidases/imunologia , Adulto , Idoso , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/efeitos dos fármacos , Estudos Prospectivos
14.
Neuromuscul Disord ; 22 Suppl 2: S148-54, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22980766

RESUMO

Late-onset Pompe disease is characterized by progressive weakness involving proximal limb and respiratory muscles. Recently, treatment with enzyme replacement therapy (ERT) has been introduced partially improving patients' prognosis, but a standard consensus on when to start ERT is still lacking. There is also a lack of biomarkers related to the clinical progression of the disease. Here we used muscle magnetic resonance imaging (MRI) or computed tomography (CT) to study the abdominal and paravertebral muscles of 30 late-onset Pompe patients at different stages of disease. We observed a selective pattern of muscle damage, with early involvement of the Multifidus muscle, followed by the Obliquus internus abdominis and Longissimus muscle. Some degree of trunk involvement on MRI occurred even in asymptomatic patients. Severity of muscle involvement in MRI correlated with patients' functional stage. We suggest that: (a) the combination of paravertebral and abdominal muscle involvement may serve as a useful tool in the diagnostic work-up of patients with a clinical suspicion of Pompe disease; (b) trunk abnormalities appear at very early stages of disease and even in asymptomatic patients, possibly "announcing" the onset of the disease and thus the need for a closer clinical follow-up.


Assuntos
Doença de Depósito de Glicogênio Tipo II/diagnóstico , Músculo Esquelético/patologia , Tronco/patologia , Adulto , Idoso , Progressão da Doença , Feminino , Doença de Depósito de Glicogênio Tipo II/classificação , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Radiografia , Tomógrafos Computadorizados , Tronco/diagnóstico por imagem , Adulto Jovem
15.
Clin Transl Oncol ; 12(2): 150-3, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20156785

RESUMO

Lobular breast carcinoma represents 2-20% of infiltrative carcinomas of the breast. The incidence of extrahepatic gastrointestinal (GI) tract metastases observed in necropsy studies varies from 6% to 18% and the most commonly affected organ is the stomach, followed by colon and rectum [1-4]. Reported herein is the case of a 67-year-old woman who was primarily diagnosed and surgically treated for a lobular carcinoma of the breast 15 years ago and is now referred with back pain and right hydronephrosis caused by a metastasis in rectum. Frequently, the absence of specific symptoms of digestive metastases of breast cancer leads to a misdiagnosis of this pathology [5-7]. The treatment will be based on a detailed clinical history and histopathological findings. Metastases from breast cancer in GI tract tumours must be excluded in a patient with previous history of breast carcinoma, as in the case reported herein.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Lobular/patologia , Neoplasias Retais/diagnóstico , Neoplasias Retais/secundário , Idoso , Neoplasias da Mama/diagnóstico , Carcinoma Lobular/diagnóstico , Feminino , Humanos , Neoplasias Retais/patologia , Fatores de Tempo
16.
Cir Esp ; 85(3): 140-6, 2009 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-19264296

RESUMO

Reduction mammaplasty techniques enable the breast cancer surgeon to provide an integral surgical treatment, thus significantly increasing and improving surgical options. These techniques are used to correct problems after the conservative treatment of type 1 breast cancer and to achieve symmetry between the breasts after mastectomy. They are also the basis of cosmetic reconstruction techniques in conservative oncoplastic surgery.


Assuntos
Neoplasias da Mama/cirurgia , Mamoplastia/métodos , Feminino , Humanos
17.
Cir. Esp. (Ed. impr.) ; 85(3): 140-146, mar. 2009. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-59910

RESUMO

El conocimiento de las técnicas de mamoplastia de reducción habilita al cirujano dedicado al cáncer de mama para realizar un tratamiento quirúrgico integral, con lo que se amplían y mejoran, de un modo importante, las opciones quirúrgicas. La mamoplastia de reducción, técnica utilizada para el tratamiento de las secuelas de la cirugía conservadora del tipo I de la clasificación de Clough, completa el proceso de reconstrucción mamaria tras mastectomía con la simetrización de la mama contralateral y es la base de las técnicas de remodelación en la cirugía oncoplástica conservadora (AU)


Reduction mammaplasty techniques enable the breast cancer surgeon to provide an integral surgical treatment, thus significantly increasing and improving surgical options. These techniques are used to correct problems after the conservative treatment of type 1 breast cancer and to achieve symmetry between the breasts after mastectomy. They are also the basis of cosmetic reconstruction techniques in conservative oncoplastic surgery (AU)


Assuntos
Humanos , Feminino , Neoplasias da Mama/cirurgia , Mamoplastia/métodos
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