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1.
J Relig Health ; 63(1): 640-651, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38238473

RESUMO

This paper presents a case study to support the hypothesis that religiosity and spirituality (R/S), as mood balancing factors, could facilitate the recovery process for patients suffering from bipolar disorder (BD) once they have been stabilized and are receiving appropriate support (e.g., in a residential rehabilitative center). After a succinct review of BD and R/S, the patient's medical history and rehabilitation pathway are described, with a particular focus on the role played by R/S. The authors found that in this case, once the patient was stabilized, R/S helped to consolidate her feelings of well-being, increasing her positive perception of social support services and ultimately her self-confidence.


Assuntos
Transtorno Bipolar , Espiritualidade , Humanos , Feminino , Identificação Social , Religião , Apoio Social , Itália
2.
Analyst ; 148(15): 3584-3593, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37403827

RESUMO

Infrared scattering-type scanning near-field optical microscopy (IR s-SNOM) and imaging is here exploited together with attenuated total reflection (ATR) IR imaging and scanning electron microscopy (SEM) to depict the chemical composition of fibers in hybrid electrospun meshes. The focus is on a recently developed bio-hybrid material for vascular tissue engineering applications, named Silkothane®, obtained in the form of nanofibrous matrices from the processing of a silk fibroin-polyurethane (SFPU) blend via electrospinning. Morphology and chemistry of single fibers, at both surface and subsurface level, have been successfully characterized with nanoscale resolution, taking advantage of the IR s-SNOM capability to portray the nanoscale depth profile of this modern material working at diverse harmonics of the signal. The applied methodology allowed to describe the superficial characteristics of the mesh up to a depth of about 100 nm, showing that SF and PU do not tend to co-aggregate to form hybrid fibers, at least at the length scale of hundreds of nanometers, and that subdomains other than the fibrillar ones can be present. More generally, in the present contribution, the depth profiling capabilities of IR s-SNOM, so far theoretically predicted and experimentally proven only on model systems, have been corroborated on a real material in its natural conditions with respect to production, opening the room for the exploitation of IR s-SNOM as valuable technique to support the production and the engineering of nanostructured materials by the precise understanding of their chemistry at the interface with the environment.

3.
Biomed Mater ; 17(5)2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35944550

RESUMO

To address the need of alternatives to autologous vessels for small-calibre vascular applications (e.g. cardiac surgery), a bio-hybrid semi-degradable material composed of silk fibroin (SF) and polyurethane (Silkothane®) was herein used to fabricate very small-calibre grafts (Øin= 1.5 mm) via electrospinning. Bio-hybrid grafts werein vitrocharacterized in terms of morphology and mechanical behaviour, and compared to similar grafts of pure SF. Similarly, two native vessels from a rodent model (abdominal aorta and vena cava) were harvested and characterized. Preliminary implants were performed on Lewis rats to confirm the suitability of Silkothane® grafts for small-calibre applications, specifically as aortic insertion and femoral shunt. The manufacturing process generated pliable grafts consisting of a randomized fibrous mesh and exhibiting similar geometrical features to rat aortas. Both Silkothane® and pure SF grafts showed radial compliances in the range from 1.37 ± 0.86 to 1.88 ± 1.01% 10-2mmHg-1, lower than that of native vessels. The Silkothane® small-calibre devices were also implanted in rats demonstrating to be adequate for vascular applications; all the treated rats survived the surgery for three months after implantation, and 16 rats out of 17 (94%) still showed blood flow inside the graft at sacrifice. The obtained results lay the basis for a deeper investigation of the interaction between the Silkothane® graft and the implant site, which may deal with further analysis on the potentialities in terms of degradability and tissue formation, on longer time-points.


Assuntos
Fibroínas , Enxerto Vascular , Animais , Prótese Vascular , Poliuretanos , Ratos , Ratos Endogâmicos Lew
4.
Quant Imaging Med Surg ; 12(7): 3515-3527, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35782271

RESUMO

Background: Performance and durability of arterio-venous grafts depend on their ability to mimic the mechanical behavior of the anastomized blood vessels. To select the most suitable synthetic graft, in vivo evaluation of the radial deformability of peripheral arteries and veins could be crucial; however, a standardized non-invasive strategy is still missing. Herein, we sought to define a novel and user-friendly clinical protocol for in vivo assessment of the arm vessel deformability. Methods: A dedicated protocol, applied on 30 volunteers, was specifically designed to estimate both compliance and distensibility of the brachial and radial arteries, and of the basilic and cephalic veins. Bi-dimensional ultrasound imaging was used to acquire cross-sectional areas (CSAs) of arteries in clinostatic configuration, and CSAs of veins combining clinostatic and orthostatic configurations. Arterial pulse pressure was measured with a digital sphygmomanometer, while venous hydrostatic pressure was derived from the arm length in orthostatic configuration. Results: For each participant, all CSAs were successfully extracted from ultrasound images. The basilic vein and the radial artery exhibited the largest (21.5±8.9 mm2) and the smallest (3.4±1.0 mm2) CSAs, respectively; CSA measurements were highly repeatable (Bland-Altman bias <10% and Pearson correlation ≥0.90, for both arteries and veins). In veins, compliance and distensibility were higher than in arteries; compliance was significantly higher (P<0.0001) in the brachial than in the radial artery (3.52×10-4 vs. 1.3×10-4 cm2/mmHg); it was three times larger in basilic veins than in cephalic veins (17.4×10-4 vs. 5.6×10-4 cm2/mmHg, P<0.0001). Conclusions: The proposed non-invasive protocol proved feasible, effective and adequate for daily clinical practice, allowing for the estimation of patient-specific compliance and distensibility of peripheral arteries and veins. If further extended, it may contribute to the fabrication of biohybrid arterio-venous grafts, paving the way towards patient-tailored solutions for vascular access.

5.
Adv Healthc Mater ; 9(20): e2000794, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32914588

RESUMO

To solve the problem of vascular access failure, a novel semi-degradable hybrid vascular graft, manufactured by electrospinning using silk fibroin and polyurethane (Silkothane), has been previously developed and characterized in vitro. This proof-of-concept animal study aims at evaluating the performances of Silkothane grafts in a sheep model of arteriovenous shunt, in terms of patency and short-term remodeling. Nine Silkothane grafts are implanted between the common carotid artery and the external jugular vein of nine sheep, examined by palpation three times per week, by echo-color Doppler every two weeks, and euthanized at 30, 60, and 90 days (N = 3 per group). At sacrifice, grafts are harvested and submitted for histopathology and/or scanning electron microcopy (SEM). No cases of graft-related complications are recorded. Eight of nine sheep (89%) show 100% primary unassisted patency at the respective time of sacrifice (flow rate 1.76 ± 0.61 L min-1 , one case of surgery-related thrombosis excluded). Histopathology and SEM analysis evidence signs of inflammation and pseudointima inside the graft lumen, especially at the venous anastomosis; however, endoluminal stenosis never impairs the functionality of the shunt and coverage by endothelial cells is observed. In this model, Silkothane grafts grant safety and 100% patency up to 90 days.


Assuntos
Fibroínas , Animais , Prótese Vascular , Células Endoteliais , Oclusão de Enxerto Vascular , Politetrafluoretileno , Poliuretanos , Diálise Renal , Ovinos , Grau de Desobstrução Vascular
6.
Biomed Mater ; 14(2): 025007, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30620939

RESUMO

Clinically available alternatives of vascular access for long-term haemodialysis-currently limited to native arteriovenous fistulae and synthetic grafts-suffer from several drawbacks and are associated to high failure rates. Bioprosthetic grafts and tissue-engineered blood vessels are costly alternatives without clearly demonstrated increased performance. In situ tissue engineering could be the ideal approach to provide a vascular access that profits from the advantages of vascular grafts in the short-term (e.g. early cannulation) and of fistulae in the long-term (e.g. high success rates driven by biointegration). Hence, in this study a three-layered silk fibroin/polyurethane vascular graft was developed by electrospinning to be applied as long-term haemodialysis vascular access pursuing a 'hybrid' in situ engineering approach (i.e. based on a semi-degradable scaffold). This Silkothane® graft was characterized concerning morphology, mechanics, physical properties, blood contact and vascular cell adhesion/viability. The full three-layered graft structure, influenced by the polyurethane presence, ensured mechanical properties that are a determinant factor for the success of a vascular access (e.g. vein-graft compliance matching). The Silkothane® graft demonstrated early cannulation potential in line with self-sealing commercial synthetic arteriovenous grafts, and a degradability driven by enzymatic activity. Moreover, the fibroin-only layers and extracellular matrix-like morphology, presented by the graft, revealed to be crucial in providing a non-haemolytic character, long clotting time, and favourable adhesion of human umbilical vein endothelial cells with increasing viability after 3 and 7 d. Accordingly, the proposed approach may represent a step forward towards an in situ engineered hybrid vascular access with potentialities for vein-graft anastomosis stability, early cannulation, and biointegration.


Assuntos
Prótese Vascular , Fibroínas/química , Poliuretanos/química , Diálise Renal/instrumentação , Engenharia Tecidual/métodos , Dispositivos de Acesso Vascular , Animais , Materiais Biocompatíveis/química , Testes de Coagulação Sanguínea , Bombyx , Adesão Celular , Sobrevivência Celular , Eletroquímica , Hemólise , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação , Permeabilidade , Diálise Renal/métodos , Estresse Mecânico , Suturas , Resistência à Tração
7.
J Biomed Mater Res B Appl Biomater ; 107(3): 807-817, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30102833

RESUMO

Several attempts made so far to combine silk fibroin and polyurethane, in order to prepare scaffolds encompassing the bioactivity of the former with the elasticity of the latter, suffer from critical drawbacks concerning industrial and clinical applicability (e.g., separation of phases upon processing, use of solvents unaddressed by the European Pharmacopoeia, and use of degradable polyurethanes). Overcoming these limitations, in this study, we report the successful blending of regenerated silk fibroin with a medical-grade, non-degradable polyurethane using formic acid and dichloromethane, and the manufacturing of hybrid, semi-degradable electrospun tubular meshes with different ratios of the two materials. Physicochemical analyses demonstrated the maintenance of the characteristic features of fibroin and polyurethane upon solubilization, blending, electrospinning, and postprocessing with ethanol or methanol. Envisioning their possible application as semidegradable substrates for haemodialysis arteriovenous grafts, tubular meshes were further characterized, showing submicrometric fibrous morphologies, tunable mechanical properties, permeability before and after puncture in the same order of magnitude as commercial grafts currently used in the clinics. Results demonstrate the potential of this material for the development of hybrid, new-generation vascular grafts with disruptive potential in the field of in situ tissue engineering. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 807-817, 2019.


Assuntos
Materiais Biocompatíveis/química , Prótese Vascular , Fibroínas/química , Poliuretanos/química , Diálise Renal , Animais , Humanos
8.
PLoS One ; 11(9): e0161479, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27584727

RESUMO

Articular cartilage has poor healing ability and cartilage injuries often evolve to osteoarthritis. Cell-based strategies aiming to engineer cartilaginous tissue through the combination of biocompatible scaffolds and articular chondrocytes represent an alternative to standard surgical techniques. In this context, perfusion bioreactors have been introduced to enhance cellular access to oxygen and nutrients, hence overcoming the limitations of static culture and improving matrix deposition. Here, we combined an optimized cocktail of soluble factors, the BIT (BMP-2, Insulin, Thyroxin), and clinical-grade collagen sponges with a bidirectional perfusion bioreactor, namely the oscillating perfusion bioreactor (OPB), to engineer in vitro articular cartilage by human articular chondrocytes (HACs) obtained from osteoarthritic patients. After amplification, HACs were seeded and cultivated in collagen sponges either in static or dynamic conditions. Chondrocyte phenotype and the nature of the matrix synthesized by HACs were assessed using western blotting and immunohistochemistry analyses. Finally, the stability of the cartilaginous tissue produced by HACs was evaluated in vivo by subcutaneous implantation in nude mice. Our results showed that perfusion improved the distribution and quality of cartilaginous matrix deposited within the sponges, compared to static conditions. Specifically, dynamic culture in the OPB, in combination with the BIT cocktail, resulted in the homogeneous production of extracellular matrix rich in type II collagen. Remarkably, the production of type I collagen, a marker of fibrous tissues, was also inhibited, indicating that the association of the OPB with the BIT cocktail limits fibrocartilage formation, favoring the reconstruction of hyaline cartilage.


Assuntos
Condrócitos/metabolismo , Colágeno Tipo I/biossíntese , Osteoartrite/metabolismo , Tecidos Suporte , Animais , Reatores Biológicos , Western Blotting , Cartilagem Articular/patologia , Meios de Cultura , Cobaias , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Nus , Osteoartrite/patologia , Engenharia Tecidual
9.
J Appl Biomater Biomech ; 8(2): 68-75, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20740468

RESUMO

PURPOSE: Since stretching plays a key role in skeletal muscle tissue development in vivo, by making use of an innovative bioreactor and a biodegradable microfibrous scaffold (DegraPol(R)) previously developed by our group, we aimed to investigate the effect of mechanical conditioning on the development of skeletal muscle engineered constructs, obtained by seeding and culturing murine skeletal muscle cells on electrospun membranes. METHODS: Following 5 days of static culture, skeletal muscle constructs were transferred into the bioreactor and further cultured for 13 days, while experiencing a stretching pattern adapted from the literature to resemble mouse development and growth. Sample withdrawal occurred at the onset of cyclic stretching and after 7 and 10 days. Myosin heavy chain (MHC) accumulation in stretched constructs (D) was evaluated by Western blot analysis and immunofluorescence staining, using statically cultured samples (S) as controls. RESULTS: Western blot analysis of MHC on dynamically (D) and statically (S) cultured constructs at different time points showed that, at day 10, the applied stretching pattern led to an eight-fold increase in myosin accumulation in cyclically stretched constructs (D) with respect to the corresponding static controls (S). These results were confirmed by immunofluorescence staining of total sarcomeric MHC. CONCLUSIONS: Since previous attempts to reproduce skeletal myogenesis in vitro mainly suffered from the difficulty of driving myoblast development into an architecturally organized array of myosin expressing myotubes, the chance of inducing MHC accumulation via mechanical conditioning represents a significant step towards the generation of a functional muscle construct for skeletal muscle tissue engineering applications.


Assuntos
Reatores Biológicos , Desenvolvimento Muscular , Músculo Esquelético/metabolismo , Cadeias Pesadas de Miosina/biossíntese , Engenharia Tecidual/métodos , Animais , Técnicas de Cultura de Células , Linhagem Celular , Camundongos , Músculo Esquelético/crescimento & desenvolvimento
10.
Adv Mater ; 21(32-33): 3352-67, 2009 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-20882502

RESUMO

Over the last decade, we have witnessed an increased recognition of the importance of 3D culture models to study various aspects of cell physiology and pathology, as well as to engineer implantable tissues. As compared to well-established 2D cell-culture systems, cell/tissue culture within 3D porous biomaterials has introduced new scientific and technical challenges associated with complex transport phenomena, physical forces, and cell-microenvironment interactions. While bioreactor-based 3D model systems have begun to play a crucial role in addressing fundamental scientific questions, numerous hurdles currently impede the most efficient utilization of these systems. We describe how computational modeling and innovative sensor technologies, in conjunction with well-defined and controlled bioreactor-based 3D culture systems, will be key to gain further insight into cell behavior and the complexity of tissue development. These model systems will lay a solid foundation to further develop, optimize, and effectively streamline the essential bioprocesses to safely and reproducibly produce appropriately scaled tissue grafts for clinical studies.

11.
Biomaterials ; 26(22): 4606-15, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15722130

RESUMO

Skeletal muscle tissue engineering represents an attractive approach to overcome problems associated with autologous transfer of muscle tissue and provides a valid alternative in muscle regeneration enhancement. The aim of this study was to investigate the suitability, as scaffold for skeletal muscle tissue engineering, of a known biodegradable block copolymer (DegraPol) processed by electrospinning in the novel form of microfibrous membranes. Scaffolds were characterized with reference to their morphological, degradative and mechanical properties. Subsequently, cell viability, adhesion and differentiation on coated and uncoated DegraPol) slides were investigated using line cells (C2C12 and L6) and primary human satellite cells (HSCs). The membranes exhibited absence of toxic residuals and satisfactory mechanical properties (linear elastic behavior up to 10% deformation, E modulus in the order of magnitude of MPa). A promising cellular response was also found in preliminary experiments: both line cells and HSCs adhered, proliferated and fused on differently coated electrospun membranes. Positive staining for myosin heavy chain expression indicated that differentiation of C2C12 multinucleated cells occurred within the porous elastomeric substrate. Together the results of this study provide significant evidence of the suitability of electrospun DegraPol) membranes as scaffolds for skeletal muscle tissue engineering and that they represent a promising alternative to scaffolds currently used in this field.


Assuntos
Membranas Artificiais , Músculo Esquelético/citologia , Poliésteres , Engenharia Tecidual , Uretana , Adesão Celular , Diferenciação Celular , Linhagem Celular , Sobrevivência Celular , Humanos , Microscopia Eletrônica de Varredura
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