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[PMID]:29373598
[Au] Autor:Maccabi A; Shin A; Namiri NK; Bajwa N; St John M; Taylor ZD; Grundfest W; Saddik GN
[Ad] Endereço:Department of Electrical Engineering, University of California, Los Angeles, Los Angeles, CA, United States of America.
[Ti] Título:Quantitative characterization of viscoelastic behavior in tissue-mimicking phantoms and ex vivo animal tissues.
[So] Source:PLoS One;13(1):e0191919, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Viscoelasticity of soft tissue is often related to pathology, and therefore, has become an important diagnostic indicator in the clinical assessment of suspect tissue. Surgeons, particularly within head and neck subsites, typically use palpation techniques for intra-operative tumor detection. This detection method, however, is highly subjective and often fails to detect small or deep abnormalities. Vibroacoustography (VA) and similar methods have previously been used to distinguish tissue with high-contrast, but a firm understanding of the main contrast mechanism has yet to be verified. The contributions of tissue mechanical properties in VA images have been difficult to verify given the limited literature on viscoelastic properties of various normal and diseased tissue. This paper aims to investigate viscoelasticity theory and present a detailed description of viscoelastic experimental results obtained in tissue-mimicking phantoms (TMPs) and ex vivo tissues to verify the main contrast mechanism in VA and similar imaging modalities. A spherical-tip micro-indentation technique was employed with the Hertzian model to acquire absolute, quantitative, point measurements of the elastic modulus (E), long term shear modulus (η), and time constant (τ) in homogeneous TMPs and ex vivo tissue in rat liver and porcine liver and gallbladder. Viscoelastic differences observed between porcine liver and gallbladder tissue suggest that imaging modalities which utilize the mechanical properties of tissue as a primary contrast mechanism can potentially be used to quantitatively differentiate between proximate organs in a clinical setting. These results may facilitate more accurate tissue modeling and add information not currently available to the field of systems characterization and biomedical research.
[Mh] Termos MeSH primário: Elasticidade
Modelos Animais
Imagens de Fantasmas
Viscosidade
[Mh] Termos MeSH secundário: Animais
Masculino
Ratos Sprague-Dawley
Suínos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180127
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0191919


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[PMID]:28457187
[Au] Autor:Munarin F; Kaiser NJ; Kim TY; Choi BR; Coulombe KLK
[Ad] Endereço:1 School of Engineering, Brown University , Providence, Rhode Island.
[Ti] Título:Laser-Etched Designs for Molding Hydrogel-Based Engineered Tissues.
[So] Source:Tissue Eng Part C Methods;23(5):311-321, 2017 05.
[Is] ISSN:1937-3392
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Rapid prototyping and fabrication of elastomeric molds for sterile culture of engineered tissues allow for the development of tissue geometries that can be tailored to different in vitro applications and customized as implantable scaffolds for regenerative medicine. Commercially available molds offer minimal capabilities for adaptation to unique conditions or applications versus those for which they are specifically designed. Here we describe a replica molding method for the design and fabrication of poly(dimethylsiloxane) (PDMS) molds from laser-etched acrylic negative masters with ∼0.2 mm resolution. Examples of the variety of mold shapes, sizes, and patterns obtained from laser-etched designs are provided. We use the patterned PDMS molds for producing and culturing engineered cardiac tissues with cardiomyocytes derived from human-induced pluripotent stem cells. We demonstrate that tight control over tissue morphology and anisotropy results in modulation of cell alignment and tissue-level conduction properties, including the appearance and elimination of reentrant arrhythmias, or circular electrical activation patterns. Techniques for handling engineered cardiac tissues during implantation in vivo in a rat model of myocardial infarction have been developed and are presented herein to facilitate development and adoption of surgical techniques for use with hydrogel-based engineered tissues. In summary, the method presented herein for engineered tissue mold generation is straightforward and low cost, enabling rapid design iteration and adaptation to a variety of applications in tissue engineering. Furthermore, the burden of equipment and expertise is low, allowing the technique to be accessible to all.
[Mh] Termos MeSH primário: Hidrogéis/química
Lasers
Infarto do Miocárdio/terapia
Miócitos Cardíacos/citologia
Engenharia Tecidual/métodos
[Mh] Termos MeSH secundário: Animais
Animais Recém-Nascidos
Células Cultivadas
Elasticidade
Seres Humanos
Masculino
Miócitos Cardíacos/fisiologia
Ratos
Ratos Sprague-Dawley
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hydrogels)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE
[do] DOI:10.1089/ten.TEC.2017.0068


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[PMID]:29227513
[Au] Autor:Vinciguerra R; Romano V; Arbabi EM; Brunner M; Willoughby CE; Batterbury M; Kaye SB
[Ti] Título:In Vivo Early Corneal Biomechanical Changes After Corneal Cross-linking in Patients With Progressive Keratoconus.
[So] Source:J Refract Surg;33(12):840-846, 2017 Dec 01.
[Is] ISSN:1081-597X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:PURPOSE: To report early corneal biomechanical changes after corneal cross-linking (CXL) in patients with keratoconus. METHODS: Thirty-four eyes of 34 patients undergoing CXL for progressive keratoconus were included in this prospective clinical study. Dynamic corneal response (DCR) parameters obtained with the Corvis ST (OCULUS Optikgeräte GmbH; Wetzlar, Germany) were assessed at baseline (day of CXL) and after 1 month of follow-up; conversely, corneal tomography with the Pentacam (OCULUS Optikgeräte GmbH) was assessed at baseline and at 1, 3, and 6 months after CXL. RESULTS: At the last follow-up visit (123.7 ± 69.6 days), all morphological parameters including steepest point (Kmax) and thinnest corneal thickness (ThCT) indicated stabilization of keratoconus (P > .05). Comparative analyses showed a rise of corneal stiffness demonstrated by a significant increase of Stiffness Parameter A1 (SP-A1) and Highest Concavity (SP-HC) and a significant decrease of Inverse Concave Radius (1/R) and Deformation Amplitude Ratio (DA Ratio) (P < .05). There was a significant correlation between the preoperative keratoconus characteristics (Kmax, Belin/Ambrósio final D value [BAD-D], and ThCT) and the DCR parameters (P < .05). Kmax and BAD-D showed a significant positive correlation with DA Ratio, Deflection Amplitude (DefA), and 1/R and a significant negative correlation with SPA1 and SP-HC. ThCT showed a significant positive correlation with SP-A1 and SP-HC and a significant negative correlation with DA Ratio, DefA, and 1/R. CONCLUSIONS: This study suggests that the new DCR parameters of the Corvis ST are able to detect early changes in biomechanics following CXL and those that are measurable before corneal shape modifications take place. Based on these results, the authors suggest the use of these metrics to assess the early efficacy of cross-linking. [J Refract Surg. 2017;33(12):840-846.].
[Mh] Termos MeSH primário: Córnea/fisiologia
Reagentes para Ligações Cruzadas
Elasticidade/fisiologia
Ceratocone/tratamento farmacológico
Fotoquimioterapia
Fármacos Fotossensibilizantes/uso terapêutico
Riboflavina/uso terapêutico
[Mh] Termos MeSH secundário: Adulto
Fenômenos Biomecânicos
Colágeno/metabolismo
Substância Própria/metabolismo
Topografia da Córnea
Feminino
Seres Humanos
Ceratocone/metabolismo
Ceratocone/fisiopatologia
Masculino
Estudos Prospectivos
Raios Ultravioleta
Acuidade Visual/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cross-Linking Reagents); 0 (Photosensitizing Agents); 9007-34-5 (Collagen); TLM2976OFR (Riboflavin)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171212
[St] Status:MEDLINE
[do] DOI:10.3928/1081597X-20170922-02


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[PMID]:28470532
[Au] Autor:Dakhil H; Wierschem A
[Ad] Endereço:Institute of Fluid Mechanics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstr. 4, Erlangen, 91058, Germany.
[Ti] Título:Average Rheological Quantities of Cells in Monolayers.
[So] Source:Methods Mol Biol;1601:257-266, 2017.
[Is] ISSN:1940-6029
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Measuring rheological properties of cells in monolayers enables quantifying average cell properties in single experimental runs despite large cell-to-cell variations. Here, we describe how to modify a commercial rotational rheometer to accomplish the necessary precision for a monolayer rheometer and we delineate the steps for setting up experiments detecting average viscoelastic cell properties.
[Mh] Termos MeSH primário: Reologia/instrumentação
Análise de Célula Única/instrumentação
[Mh] Termos MeSH secundário: Adesão Celular
Células Cultivadas
Elasticidade
Fibroblastos/química
Corantes Fluorescentes/química
Células HeLa
Seres Humanos
Estresse Mecânico
Viscosidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fluorescent Dyes)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180219
[Lr] Data última revisão:
180219
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE
[do] DOI:10.1007/978-1-4939-6960-9_20


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[PMID]:27777117
[Au] Autor:MacManus DB; Pierrat B; Murphy JG; Gilchrist MD
[Ad] Endereço:School of Mechanical & Materials Engineering, University College Dublin, Dublin, Ireland. Electronic address: david.mac-manus@ucdconnect.ie.
[Ti] Título:A viscoelastic analysis of the P56 mouse brain under large-deformation dynamic indentation.
[So] Source:Acta Biomater;48:309-318, 2017 01 15.
[Is] ISSN:1878-7568
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The brain is a complex organ made up of many different functional and structural regions consisting of different types of cells such as neurons and glia, as well as complex anatomical geometries. It is hypothesized that the different regions of the brain exhibit significantly different mechanical properties which may be attributed to the diversity of cells within individual brain regions. The regional viscoelastic properties of P56 mouse brain tissue, up to 70µm displacement, are presented and discussed in the context of traumatic brain injury, particularly how the different regions of the brain respond to mechanical loads. Force-relaxation data obtained from micro-indentation measurements were fit to both linear and quasi-linear viscoelastic models to determine the time and frequency domain viscoelastic response of the pons, cortex, medulla oblongata, cerebellum, and thalamus. The damping ratio of each region was also determined. Each region was found to have a unique mechanical response to the applied displacement, with the pons and thalamus exhibiting the largest and smallest force-response, respectively. All brain regions appear to have an optimal frequency for the dissipation of energies which lies between 1 and 10Hz. STATEMENT OF SIGNIFICANCE: We present the first mechanical characterization of the viscoelastic response for different regions of mouse brain. Force-relaxation tests are performed under large strain dynamic micro-indentation, and viscoelastic models are used subsequently, providing time-dependent mechanical properties of brain tissue under loading conditions comparable to what is experienced in TBI. The unique mechanical properties of different brain regions are highlighted, with substantial variations in the viscoelastic properties and damping ratio of each region. Cortex and pons were the stiffest regions, while the thalamus and medulla were most compliant. The cerebellum and thalamus had highest damping ratio values and those of the medulla were lowest. The reported material parameters can be implemented into finite element computer models of the mouse to investigate the effects of trauma on individual brain regions.
[Mh] Termos MeSH primário: Encéfalo/fisiologia
Elasticidade
[Mh] Termos MeSH secundário: Animais
Fenômenos Biomecânicos
Módulo de Elasticidade
Análise de Elementos Finitos
Camundongos
Fatores de Tempo
Viscosidade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1711
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161026
[St] Status:MEDLINE


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[PMID]:29419681
[Au] Autor:Park GY; Kwon DR; Kwon DG
[Ad] Endereço:Department of Rehabilitation Medicine, Catholic University of Daegu School of Medicine, Daegu, South Korea.
[Ti] Título:Shear wave sonoelastography in infants with congenital muscular torticollis.
[So] Source:Medicine (Baltimore);97(6):e9818, 2018 Feb.
[Is] ISSN:1536-5964
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Congenital muscular torticollis (CMT) is characterized by shortening or excessive contraction of the sternocleidomastoid muscle (SCM). The main purpose of this study was to evaluate the feasibility of quantifying SCM stiffness using acoustic radiation force impulse (ARFI) sonoelastography in infants with CMT. Twenty infants with an SCM thickness greater than 10 mm with or without involvement of the entire SCM length (limitation of neck rotation passive range of motion [PROM]: group 1S >30°, group 1M = 15°-30°) and 12 infants with an SCM thickness smaller than 10 mm with or without involvement of any part of SCM (group 2) were included. The SCM thickness was measured using real time B-mode ultrasound, and the local SCM shear wave velocity (SWV) and subcutaneous fat layer using ARFI sonoelastography. The neck rotation PROM was significantly greater in group 1S (36.5°â€Š±â€Š5.3°) than in group 1M (18.8°â€Š±â€Š4.9°; P < .01); the SWV of the SCM in the affected side (2.96 ±â€Š0.99 m/s) was significantly higher than that in the unaffected side (1.50 ±â€Š0.30 m/s; P < .01) in group 1. The SWV of the SCM was significantly higher in group 1S than in group 1M. There was significant correlation between the degree of PROM deficit of neck rotation and the SWV of the affected SCM (r = .75; P < .01) in all infants. This study revealed a difference in the SWV of the affected SCM in relationship to the limitation of neck rotation PROM in infants with CMT, if there was no difference in SCM thickness among infants.
[Mh] Termos MeSH primário: Técnicas de Imagem por Elasticidade/métodos
Músculos do Pescoço
Torcicolo/congênito
[Mh] Termos MeSH secundário: Estudos Transversais
Elasticidade/fisiologia
Feminino
Seres Humanos
Lactente
Masculino
Contração Muscular/fisiologia
Músculos do Pescoço/diagnóstico por imagem
Músculos do Pescoço/fisiopatologia
Amplitude de Movimento Articular
República da Coreia
Estatística como Assunto
Torcicolo/diagnóstico
Torcicolo/fisiopatologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180214
[Lr] Data última revisão:
180214
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:180209
[St] Status:MEDLINE
[do] DOI:10.1097/MD.0000000000009818


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[PMID]:29328637
[Au] Autor:Filipovic M; Gledovic A; Lukic M; Tasic-Kostov M; Isailovic T; Pantelic I; Vuleta G; Savic S
[Ti] Título:Alp Rose stem cells, olive oil squalene and a natural alkyl polyglucoside emulsifier: Are they appropriate ingredients of skin moisturizers - in vivo efficacy on normal and sodium lauryl sulfate - irritated skin?.
[So] Source:Vojnosanit Pregl;73(11):991-1002, 2016 11.
[Is] ISSN:0042-8450
[Cp] País de publicação:Serbia
[La] Idioma:eng
[Ab] Resumo:Background/Aim: Since skin moisturization may be achieved by both actives and chosen carrier, plant stem cells, squalene and natural alkyl polyglucoside emulsifier may be potential components of contemporary cosmetic products. The aim of the study was in vivo evaluation of the skin irritation potential and the efficacy of Alpine Rose stem cells incorporated into li-posomes and olive oil squalene as ingredients of moisturizing creams, with respect to the novel emulsifier used for creams' stabilization. Methods: With the employment of noninvasive skin biophysical measurements, skin hydration (EC), transepi-dermal water loss (TEWL), erythema index (EI) and viscoelas-ticity were measured on 76 healthy volunteers. In the first phase, skin irritation after a 24-hour occlusion and the long-term efficacy of creams (a 21-day study) on healthy skin were evaluated. Phase II of the study focused on the cream efficacy assessment after a 6-day treatment of sodium lauryl sulfate-irritated skin. Results: After a 24-hour occlusion, there were no significant changes in the EI for any tested sample. In the second phase of the study, the EI was not significantly altered for the cream containing squalene, while the application of all active samples resulted in a significant reduction of TEWL. In both phases of the study an EC increase was recorded, espe-cially for the squalene-containing cream. Conclusion: Due to the lack of skin irritation and skin barrier impairment along with the marked hydration effect, it could be said that the in-vestigated actives incorporated into alkyl polyglucoside emulsi-fier-stabilized creams may be safely applied as ingredients for "tailor-made" cosmetic moisturizers intended for normal and dry skin care, whereas olive oil squalene could be used for the treatment of irritated or sensitive skin as well. [Projekat Ministarstva nauke Republike Srbije, br. TR34031]
[Mh] Termos MeSH primário: Emulsificantes/administração & dosagem
Glucosídeos/administração & dosagem
Azeite de Oliva/química
Rhododendron/citologia
Creme para a Pele/administração & dosagem
Testes de Irritação da Pele/métodos
Pele/efeitos dos fármacos
Dodecilsulfato de Sódio/toxicidade
Esqualeno/administração & dosagem
Células-Tronco/fisiologia
[Mh] Termos MeSH secundário: Administração Cutânea
Adulto
Segurança de Produtos ao Consumidor
Método Duplo-Cego
Elasticidade
Emulsificantes/efeitos adversos
Feminino
Glucosídeos/efeitos adversos
Seres Humanos
Lipossomos
Fitoterapia
Plantas Medicinais
Medição de Risco
Sérvia
Pele/metabolismo
Pele/patologia
Creme para a Pele/efeitos adversos
Esqualeno/efeitos adversos
Esqualeno/isolamento & purificação
Fatores de Tempo
Viscosidade
Perda Insensível de Água/efeitos dos fármacos
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL
[Nm] Nome de substância:
0 (Emulsifying Agents); 0 (Glucosides); 0 (Liposomes); 0 (Olive Oil); 368GB5141J (Sodium Dodecyl Sulfate); 7QWM220FJH (Squalene)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180213
[Lr] Data última revisão:
180213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180113
[St] Status:MEDLINE
[do] DOI:10.2298/VSP150116122F


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[PMID]:29301069
[Au] Autor:Li Q; Zhao Z
[Ad] Endereço:College of Light Industry and Food Engineering, Guangxi University , Nanning, Guangxi 530004, People's Republic of China.
[Ti] Título:Characterization of the Structural and Colloidal Properties of α-Lactalbumin/Chitosan Complexes as a Function of Heating.
[So] Source:J Agric Food Chem;66(4):972-978, 2018 Jan 31.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This research investigated the interaction between α-lactalbumin (α-la) and chitosan at different temperatures. Chitosan was added to α-la solution (5 g L ) to achieve different α-la/chitosan ratios (8:1, 5:1, and 2:1), which were then subjected to different heating temperatures (20, 70, and 90 °C). The results indicated that a low amount of chitosan (8:1) precipitated α-la molecules. Increasing chitosan to a ratio of 5:1 resulted in exposure of the internal structure of α-la, and those formed complexes had high turbidity and average size, which were decreased by an increasing temperature. A further increase of chitosan to a ratio of 2:1 protected the internal structure of α-la molecules. All samples exhibited a similar adsorption behavior at the air/water interface, but the presence of chitosan significantly increased film elasticity. The produced complexes can be regarded as functional ingredients, which can be used as an emulsifying agent and a delivery material to control the release of bioactive compounds.
[Mh] Termos MeSH primário: Quitosana/química
Coloides/química
Temperatura Alta
Lactalbumina/química
[Mh] Termos MeSH secundário: Adsorção
Precipitação Química
Difusão Dinâmica da Luz
Elasticidade
Indústria Alimentícia
Nefelometria e Turbidimetria
Soluções
Espectrometria de Fluorescência
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Colloids); 0 (Solutions); 9012-76-4 (Chitosan); 9013-90-5 (Lactalbumin)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180105
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b04628


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[PMID]:29236205
[Au] Autor:Chiti MC; Dolmans MM; Mortiaux L; Zhuge F; Ouni E; Shahri PAK; Van Ruymbeke E; Champagne SD; Donnez J; Amorim CA
[Ad] Endereço:Pôle de Recherche en Gynécologie, Institut de Recherche Expérimentale et Clinique, Université Catholique de Louvain, Avenue Mounier 52, bte. B1.52.02, 1200, Brussels, Belgium.
[Ti] Título:A novel fibrin-based artificial ovary prototype resembling human ovarian tissue in terms of architecture and rigidity.
[So] Source:J Assist Reprod Genet;35(1):41-48, 2018 Jan.
[Is] ISSN:1573-7330
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:PURPOSE: The aim of this study is to optimize fibrin matrix composition in order to mimic human ovarian tissue architecture for human ovarian follicle encapsulation and grafting. METHODS: Ultrastructure of fresh human ovarian cortex in age-related women (n = 3) and different fibrin formulations (F12.5/T1, F30/T50, F50/T50, F75/T75), rheology of fibrin matrices and histology of isolated and encapsulated human ovarian follicles in these matrices. RESULTS: Fresh human ovarian cortex showed a highly fibrous and structurally inhomogeneous architecture in three age-related patients, but the mean ± SD of fiber thickness (61.3 to 72.4 nm) was comparable between patients. When the fiber thickness of four different fibrin formulations was compared with human ovarian cortex, F50/T50 and F75/T75 showed similar fiber diameters to native tissue, while F12.5/T1 was significantly different (p value < 0.01). In addition, increased concentrations of fibrin exhibited enhanced storage modulus with F50/T50, resembling physiological ovarian rigidity. Excluding F12.5/T1 from further analysis, only three remaining fibrin matrices (F30/T50, F50/T50, F75/T75) were histologically investigated. For this, frozen-thawed fragments of human ovarian tissue collected from 22 patients were used to isolate ovarian follicles and encapsulate them in the three fibrin formulations. All three yielded similar follicle recovery and loss rates soon after encapsulation. Therefore, based on fiber thickness, porosity, and rigidity, we selected F50/T50 as the fibrin formulation that best mimics native tissue. CONCLUSIONS: Of all the different fibrin matrix concentrations tested, F50/T50 emerged as the combination of choice in terms of ultrastructure and rigidity, most closely resembling human ovarian cortex.
[Mh] Termos MeSH primário: Órgãos Artificiais
Fibrina/química
Ovário
[Mh] Termos MeSH secundário: Materiais Biomiméticos/química
Composição de Medicamentos
Elasticidade
Feminino
Dureza
Seres Humanos
Fenômenos Mecânicos
Folículo Ovariano/transplante
Folículo Ovariano/ultraestrutura
Ovário/química
Ovário/citologia
Ovário/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9001-31-4 (Fibrin)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180210
[Lr] Data última revisão:
180210
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171214
[St] Status:MEDLINE
[do] DOI:10.1007/s10815-017-1091-3


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[PMID]:29201301
[Au] Autor:Farajpour H; Jamshidi N
[Ad] Endereço:Department of Biomedical Engineering, Faculty of Engineering, University of Isfahan, Isfahan, Iran.
[Ti] Título:Effects of Different Angles of the Traction Table on Lumbar Spine Ligaments: A Finite Element Study.
[So] Source:Clin Orthop Surg;9(4):480-488, 2017 Dec.
[Is] ISSN:2005-4408
[Cp] País de publicação:Korea (South)
[La] Idioma:eng
[Ab] Resumo:Background: The traction bed is a noninvasive device for treating lower back pain caused by herniated intervertebral discs. In this study, we investigated the impact of the traction bed on the lower back as a means of increasing the disc height and creating a gap between facet joints. Methods: Computed tomography (CT) images were obtained from a female volunteer and a three-dimensional (3D) model was created using software package MIMICs 17.0. Afterwards, the 3D model was analyzed in an analytical software (Abaqus 6.14). The study was conducted under the following traction loads: 25%, 45%, 55%, and 85% of the whole body weight in different angles. Results: Results indicated that the loading angle in the L3-4 area had 36.8%, 57.4%, 55.32%, 49.8%, and 52.15% effect on the anterior longitudinal ligament, posterior longitudinal ligament, intertransverse ligament, interspinous ligament, and supraspinous ligament, respectively. The respective values for the L4-5 area were 32.3%, 10.6%, 53.4%, 56.58%, and 57.35%. Also, the body weight had 63.2%, 42.6%, 44.68%, 50.2%, and 47.85% effect on the anterior longitudinal ligament, posterior longitudinal ligament, intertransverse ligament, interspinous ligament, and supraspinous ligament, respectively. The respective values for the L4-5 area were 67.7%, 89.4%, 46.6%, 43.42% and 42.65%. The authenticity of results was checked by comparing with the experimental data. Conclusions: The results show that traction beds are highly effective for disc movement and lower back pain relief. Also, an optimal angle for traction can be obtained in a 3D model analysis using CT or magnetic resonance imaging images. The optimal angle would be different for different patients and thus should be determined based on the decreased height of the intervertebral disc, weight and height of patients.
[Mh] Termos MeSH primário: Disco Intervertebral/diagnóstico por imagem
Ligamentos Longitudinais/diagnóstico por imagem
Vértebras Lombares/diagnóstico por imagem
Tração
[Mh] Termos MeSH secundário: Adulto
Fenômenos Biomecânicos
Peso Corporal
Simulação por Computador
Elasticidade
Feminino
Análise de Elementos Finitos
Seres Humanos
Imagem Tridimensional
Disco Intervertebral/fisiologia
Ligamentos Longitudinais/fisiologia
Posicionamento do Paciente
Tomografia Computadorizada por Raios X
Tração/instrumentação
Viscosidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180207
[Lr] Data última revisão:
180207
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171205
[St] Status:MEDLINE
[do] DOI:10.4055/cios.2017.9.4.480



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