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1.
Turk Kardiyol Dern Ars ; 51(6): 369-377, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37671520

RESUMO

OBJECTIVE: Impaired arterial elastic features is one of the earliest manifestations of atherosclerosis in the vessel wall and is associated with the development of cardiovascular disease and increased mortality and morbidity. In this study, we aimed to investigate the mean values of aortic elasticity parameters in a normotensive population with transthoracic echocardiography and to evaluate these values in different age groups and their relationship with other risk factors. METHODS: This retrospective study included 405 subjects who met the inclusion criteria among 2880 individuals screened between 2020 and 2022. The study population was divided into 5 groups according to their age. Aortic elasticity parameters (aortic strain, aortic stiffness index, and aortic distensibility) were calculated from the associated formulas by measurements made from the ascending aorta in the parasternal long axis. RESULTS: In 405 subjects (mean age 42.18 ± 10.39, 54.3% female), the mean aortic strain value was 15.14 ± 3.56%, the mean aortic stiffness index was 3.24 ± 1.05, and the mean aortic distensibility was 7.48 ± 2.36 cm2/dyn1/103. It was observed that aortic strain and distensibility values significantly decreased with increasing age groups, while aortic stiffness significantly increased. All 3 aortic elasticity parameters were strongly correlated to age. In the multivariate linear regression analysis, age was found to be an independent factor for all aortic elasticity parameters. CONCLUSION: Aortic elasticity parameters can be evaluated with transthoracic echocardiography in daily practice. Comparing these measurements with normal values in similar age groups may help to detect patients with increased cardiovascular risk in the early period, regardless of the other risk factors.


Assuntos
Aorta , Elasticidade , Feminino , Humanos , Masculino , Aorta/diagnóstico por imagem , Aorta/fisiologia , Aterosclerose/diagnóstico por imagem , Ecocardiografia , Elasticidade/fisiologia , Estudos Retrospectivos , Adulto , Pessoa de Meia-Idade , Fatores Etários , Fatores de Risco de Doenças Cardíacas , Valores de Referência
2.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(1): 87-94, 2023 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-36854552

RESUMO

Extracellular matrix (ECM) has been implicated in tumor progress and chemosensitivity. Ovarian cancer brings a great threat to the health of women with a significant feature of high mortality and poor prognosis. However, the potential significance of matrix stiffness in the pattern of long non-coding RNAs (lncRNAs) expression and ovarian cancer drug sensitivity is still largely unkown. Here, based on RNA-seq data of ovarian cancer cell cultured on substrates with different stiffness, we found that a great amount of lncRNAs were upregulated in stiff group, whereas SNHG8 was significantly downregulated, which was further verified in ovarian cancer cells cultured on polydimethylsiloxane (PDMS) hydrogel. Knockdown of SNHG8 led to an impaired efficiency of homologous repair, and decreased cellular sensitivity to both etoposide and cisplatin. Meanwhile, the results of the GEPIA analysis indicated that the expression of SNHG8 was significantly decreased in ovarian cancer tissues, which was negatively correlated with the overall survival of patients with ovarian cancer. In conclusion, matrix stiffening related lncRNA SNHG8 is closely related to chemosensitivity and prognosis of ovarian cancer, which might be a novel molecular marker for chemotherapy drug instruction and prognosis prediction.


Assuntos
Elasticidade , Matriz Extracelular , Neoplasias Ovarianas , RNA Longo não Codificante , Feminino , Humanos , Cisplatino/farmacologia , Elasticidade/fisiologia , Etoposídeo , Matriz Extracelular/genética , Matriz Extracelular/fisiologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
3.
Biomaterials ; 292: 121928, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36455488

RESUMO

Regulatory T cells (Tregs) provide an essential tolerance mechanism to suppress the immune response. Induced Tregs hold the potential to treat autoimmune diseases in adoptive therapy and can be produced with stimulating signals to CD3 and CD28 in presence of the cytokine TGF-ß and IL-2. This report examines the modulation of human Treg induction by leveraging the ability of T cells to sense the mechanical stiffness of an activating substrate. Treg induction on polyacrylamide gels (PA-gels) was sensitive to the substrate's elastic modulus, increasing with greater material stiffness. Single-cell RNA-Seq analysis revealed that Treg induction on stiffer substrates involved greater use of oxidative phosphorylation (OXPHOS). Inhibition of ATP synthase significantly reduced the rate of Treg induction and abrogated the difference among gels while activation of AMPK (AMP-activated protein kinase) increased Treg induction on the softer sample but not on the harder sample. Treg induction is thus mechanosensitive and OXPHOS-dependent, providing new strategies for improving the production of these cells for cellular immunotherapy.


Assuntos
Elasticidade , Tolerância Imunológica , Linfócitos T Reguladores , Humanos , Antígenos CD28 , Citocinas/metabolismo , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fenômenos Mecânicos , Elasticidade/fisiologia
4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-970677

RESUMO

Extracellular matrix (ECM) has been implicated in tumor progress and chemosensitivity. Ovarian cancer brings a great threat to the health of women with a significant feature of high mortality and poor prognosis. However, the potential significance of matrix stiffness in the pattern of long non-coding RNAs (lncRNAs) expression and ovarian cancer drug sensitivity is still largely unkown. Here, based on RNA-seq data of ovarian cancer cell cultured on substrates with different stiffness, we found that a great amount of lncRNAs were upregulated in stiff group, whereas SNHG8 was significantly downregulated, which was further verified in ovarian cancer cells cultured on polydimethylsiloxane (PDMS) hydrogel. Knockdown of SNHG8 led to an impaired efficiency of homologous repair, and decreased cellular sensitivity to both etoposide and cisplatin. Meanwhile, the results of the GEPIA analysis indicated that the expression of SNHG8 was significantly decreased in ovarian cancer tissues, which was negatively correlated with the overall survival of patients with ovarian cancer. In conclusion, matrix stiffening related lncRNA SNHG8 is closely related to chemosensitivity and prognosis of ovarian cancer, which might be a novel molecular marker for chemotherapy drug instruction and prognosis prediction.


Assuntos
Feminino , Humanos , Cisplatino/farmacologia , Elasticidade/fisiologia , Etoposídeo , Matriz Extracelular/fisiologia , Neoplasias Ovarianas/metabolismo , RNA Longo não Codificante/metabolismo
5.
Cornea ; 41(4): 478-483, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35244628

RESUMO

PURPOSE: The purpose of this study was to evaluate the effect of Descemet membrane endothelial keratoplasty (DMEK) graft storage time on its elastic properties, measured using atomic force microscopy (AFM). METHODS: Twenty human corneas (from 10 donors), unsuitable for transplantation, were obtained from the eye bank (S. Fyodorov Eye Microsurgery State Institution, Moscow). Ten DMEK grafts were prepared and stored in the corneal storage medium, Optisol-GS at 4°C after preparation, and AFM analysis was performed within 12 hours after preparation (group A). Ten paired corneas from the respective donors were stored in Optisol-GS at 4°C for 1 week after preparation before AFM analysis (group B). Data were analyzed using the Hertz model for the evaluation of the Young modulus of elasticity. RESULTS: Force-distance curve analysis showed an increase in the Young modulus of elasticity in group B in comparison with that in group A, and the mean values were 10.4 ± 1.8 kPa and 6.77 ± 2.25 kPa, respectively (P < 0.001). There was no correlation between the Young modulus of elasticity and donor age (r = 0.110, P = 0.644), endothelial cell count (r = -0.145, P = 0.541), and procurement interval (r = 0.14, P = 0.755). CONCLUSIONS: A longer graft storage time in cold storage medium was found to significantly reduce the elasticity of the DMEK graft. Clinically, this could potentially influence the unfolding of the DMEK graft within the anterior chamber during surgery and the postoperative detachment rate.


Assuntos
Lâmina Limitante Posterior/fisiologia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Elasticidade/fisiologia , Endotélio Corneano/citologia , Sobrevivência de Enxerto/fisiologia , Preservação de Órgãos/métodos , Idoso , Sulfatos de Condroitina/farmacologia , Misturas Complexas/farmacologia , Lâmina Limitante Posterior/diagnóstico por imagem , Dextranos/farmacologia , Feminino , Gentamicinas/farmacologia , Humanos , Masculino , Microscopia de Força Atômica , Pessoa de Meia-Idade , Técnicas de Cultura de Órgãos , Fatores de Tempo , Coleta de Tecidos e Órgãos
6.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35169074

RESUMO

Cells are filled with macromolecules and polymer networks that set scale-dependent viscous and elastic properties to the cytoplasm. Although the role of these parameters in molecular diffusion, reaction kinetics, and cellular biochemistry is being increasingly recognized, their contributions to the motion and positioning of larger organelles, such as mitotic spindles for cell division, remain unknown. Here, using magnetic tweezers to displace and rotate mitotic spindles in living embryos, we uncovered that the cytoplasm can impart viscoelastic reactive forces that move spindles, or passive objects with similar size, back to their original positions. These forces are independent of cytoskeletal force generators yet reach hundreds of piconewtons and scale with cytoplasm crowding. Spindle motion shears and fluidizes the cytoplasm, dissipating elastic energy and limiting spindle recoils with functional implications for asymmetric and oriented divisions. These findings suggest that bulk cytoplasm material properties may constitute important control elements for the regulation of division positioning and cellular organization.


Assuntos
Citoplasma/fisiologia , Elasticidade/fisiologia , Fuso Acromático/fisiologia , Animais , Fenômenos Biomecânicos/fisiologia , Divisão Celular/fisiologia , Difusão , Cinética , Fenômenos Magnéticos , Microtúbulos , Mitose/fisiologia , Organelas , Ouriços-do-Mar , Viscosidade
7.
Int J Mol Sci ; 23(4)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35216218

RESUMO

Many extensible tissues such as skin, lungs, and blood vessels require elasticity to function properly. The recoil of elastic energy stored during a stretching phase is provided by elastic fibers, which are mostly composed of elastin and fibrillin-rich microfibrils. In arteries, the lack of elastic fibers leads to a weakening of the vessel wall with an increased risk to develop cardiovascular defects such as stenosis, aneurysms, and dissections. The development of new therapeutic molecules involves preliminary tests in animal models that recapitulate the disease and whose response to drugs should be as close as possible to that of humans. Due to its superior in vivo imaging possibilities and the broad tool kit for forward and reverse genetics, the zebrafish has become an important model organism to study human pathologies. Moreover, it is particularly adapted to large scale studies, making it an attractive model in particular for the first steps of investigations. In this review, we discuss the relevance of the zebrafish model for the study of elastic fiber-related vascular pathologies. We evidence zebrafish as a compelling alternative to conventional mouse models.


Assuntos
Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Tecido Elástico/metabolismo , Tecido Elástico/patologia , Fibrilinas/metabolismo , Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia , Animais , Elasticidade/fisiologia , Humanos , Proteínas dos Microfilamentos/metabolismo
8.
Int J Mol Sci ; 23(4)2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35216278

RESUMO

BACKGROUND: The aim of the research presented here was to find a set of parameters enabling discrimination between three types of fibroblasts, i.e., healthy ones and those derived from two disorders mimicking each other: idiopathic pulmonary fibrosis (IPF), and nonspecific interstitial pneumonia (NSIP). METHODS: The morphology and growth of cells were traced using fluorescence microscopy and analyzed quantitatively using cell proliferation and substrate cytotoxicity indices. The viability of cells was recorded using MTS assays, and their stiffness was examined using atomic force microscopy (AFM) working in force spectroscopy (FS) mode. To enhance any possible difference in the examined parameters, experiments were performed with cells cultured on substrates of different elasticities. Moreover, the chemical composition of cells was determined using time-of-flight secondary ion mass spectrometry (ToF-SIMS), combined with sophisticated analytical tools, i.e., Multivariate Curve Resolution (MCR) and Principal Component Analysis (PCA). RESULTS: The obtained results demonstrate that discrimination between cell lines derived from healthy and diseased patients is possible based on the analysis of the growth of cells, as well as their physical and chemical properties. In turn, the comparative analysis of the cellular response to altered stiffness of the substrates enables the identification of each cell line, including distinguishing between IPF- and NSIP-derived fibroblasts.


Assuntos
Proliferação de Células/fisiologia , Fibroblastos/patologia , Pneumonias Intersticiais Idiopáticas/patologia , Fibrose Pulmonar Idiopática/patologia , Idoso , Linhagem Celular , Elasticidade/fisiologia , Feminino , Humanos , Pulmão/patologia
9.
Invest Ophthalmol Vis Sci ; 63(2): 20, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35142787

RESUMO

Purpose: It is unclear how the iris deforms during changes in pupil size. Here, we report an application of a multi-feature iris tracking method, which we call irissometry, to investigate how the iris deforms and affects the eye position signal as a function of pupil size. Methods: To evoke pupillary responses, we repeatedly presented visual and auditory stimuli to healthy participants while we additionally recorded their right eye with a macro lens-equipped camera. We tracked changes in iris surface structure between the pupil and sclera border (limbus) by calculating local densities (distance between feature points) across evenly spaced annular iris regions. Results: The time analysis of densities showed that the inner regions of the iris stretched more strongly as compared with the outer regions of the iris during pupil constrictions. The pattern of iris densities across eccentricities and pupil size showed highly similar patterns across participants, highlighting the robustness of this elastic property. Importantly, iris-based eye position detection led to more stable signals than pupil-based detection. Conclusions: The iris regions near the pupil appear to be more elastic than the outer regions near the sclera. This elastic property explains the instability of the pupil border and the related position errors induced by eye movement and pupil size in pupil-based eye-tracking. Tracking features in the iris produce more robust eye position signals. We expect that irissometry may pave the way to novel eye trackers and diagnostic tools in ophthalmology.


Assuntos
Elasticidade/fisiologia , Tecnologia de Rastreamento Ocular , Iris/fisiologia , Pupila/fisiologia , Gravação em Vídeo , Adolescente , Adulto , Técnicas de Imagem por Elasticidade , Movimentos Oculares/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Adulto Jovem
10.
Commun Biol ; 5(1): 17, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35017622

RESUMO

Countless biophysical studies have sought distinct markers in the cellular mechanical response that could be linked to morphogenesis, homeostasis, and disease. Here, an iterative-fitting methodology visualizes the time-dependent viscoelastic behavior of human skin cells under physiologically relevant conditions. Past investigations often involved parameterizing elastic relationships and assuming purely Hertzian contact mechanics, which fails to properly account for the rich temporal information available. We demonstrate the performance superiority of the proposed iterative viscoelastic characterization method over standard open-search approaches. Our viscoelastic measurements revealed that 2D adherent metastatic melanoma cells exhibit reduced elasticity compared to their normal counterparts-melanocytes and fibroblasts, and are significantly less viscous than fibroblasts over timescales spanning three orders of magnitude. The measured loss angle indicates clear differential viscoelastic responses across multiple timescales between the measured cells. This method provides insight into the complex viscoelastic behavior of metastatic melanoma cells relevant to better understanding cancer metastasis and aggression.


Assuntos
Elasticidade/fisiologia , Fibroblastos/fisiologia , Melanócitos/fisiologia , Pele/citologia , Linhagem Celular Tumoral , Células Cultivadas , Fibroblastos/citologia , Humanos , Melanócitos/citologia , Melanoma/fisiopatologia , Neoplasias Cutâneas/fisiopatologia , Viscosidade
11.
Plant Physiol ; 188(3): 1435-1449, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34908122

RESUMO

Mechanical properties, size and geometry of cells, and internal turgor pressure greatly influence cell morphogenesis. Computational models of cell growth require values for wall elastic modulus and turgor pressure, but very few experiments have been designed to validate the results using measurements that deform the entire thickness of the cell wall. New wall material is synthesized at the inner surface of the cell such that full-thickness deformations are needed to quantify relevant changes associated with cell development. Here, we present an integrated, experimental-computational approach to analyze quantitatively the variation of elastic bending behavior in the primary cell wall of living Arabidopsis (Arabidopsis thaliana) pavement cells and to measure turgor pressure within cells under different osmotic conditions. This approach used laser scanning confocal microscopy to measure the 3D geometry of single pavement cells and indentation experiments to probe the local mechanical responses across the periclinal wall. The experimental results were matched iteratively using a finite element model of the experiment to determine the local mechanical properties and turgor pressure. The resulting modulus distribution along the periclinal wall was nonuniform across the leaf cells studied. These results were consistent with the characteristics of plant cell walls which have a heterogeneous organization. The results and model allowed the magnitude and orientation of cell wall stress to be predicted quantitatively. The methods also serve as a reference for future work to analyze the morphogenetic behaviors of plant cells in terms of the heterogeneity and anisotropy of cell walls.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Parede Celular/fisiologia , Elasticidade/fisiologia , Desenvolvimento Vegetal/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Estresse Mecânico
12.
Rev. bras. oftalmol ; 81: e0036, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1376779

RESUMO

ABSTRACT The purpose of this study was to highlight the impact of biomechanical corneal response in available in vivo tonometry methods for glaucoma management. Systematic review of non-contact air-puff tonometers that analyzes the corneal deformation response, with special focus on the investigation of the correlation of derived parameters with intraocular pressure measurements. The two actual and commercially available in vivo corneal tonometers provide promising information about biomechanical characteristics of the cornea and its relation to glaucoma, allowing the development of new protocols to evaluate, diagnose, and manage this disease.


RESUMO O objetivo deste estudo é destacar o impacto da resposta biomecânica corneana em métodos de tonometria in vivo disponíveis para o manejo do glaucoma. Trata-se de revisão sistemática de tonômetros de ar que analisa a resposta à deformação corneana, com foco especial na investigação da correlação dos parâmetros derivados com as medições da pressão intraocular. Os dois tonômetros mais recentes e comercialmente disponíveis fornecem informações promissoras sobre as características biomecânicas da córnea e sua relação com o glaucoma, permitindo o desenvolvimento de novos protocolos para avaliar, diagnosticar e controlar a doença.


Assuntos
Humanos , Tonometria Ocular/instrumentação , Tonometria Ocular/métodos , Fenômenos Biomecânicos , Córnea/anatomia & histologia , Córnea/fisiologia , Pressão Intraocular/fisiologia , Glaucoma/fisiopatologia , Hipertensão Ocular/fisiopatologia , Técnicas de Diagnóstico Oftalmológico/instrumentação , Elasticidade/fisiologia , Modelos Teóricos
13.
Sci Rep ; 11(1): 23566, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876652

RESUMO

The viscoelastic properties of red blood cells (RBC) facilitate flexible shape change in response to extrinsic forces. Their viscoelasticity is intrinsically linked to physical properties of the cytosol, cytoskeleton, and membrane-all of which are highly sensitive to supraphysiological shear exposure. Given the need to minimise blood trauma within artificial organs, we observed RBC in supraphysiological shear through direct visualisation to gain understanding of processes leading to blood damage. Using a custom-built counter-rotating shear generator fit to a microscope, healthy red blood cells (RBC) were directly visualised during exposure to different levels of shear (10-60 Pa). To investigate RBC morphology in shear flow, we developed an image analysis method to quantify (a)symmetry of deforming ellipsoidal cells-following RBC identification and centroid detection, cell radius was determined for each angle around the circumference of the cell, and the resultant bimodal distribution (and thus RBC) was symmetrically compared. While traditional indices of RBC deformability (elongation index) remained unaltered in all shear conditions, following ~100 s of exposure to 60 Pa, the frequency of asymmetrical ellipses and RBC fragments/extracellular vesicles significantly increased. These findings indicate RBC structure is sensitive to shear history, where asymmetrical morphology may indicate sublethal blood damage in real-time shear flow.


Assuntos
Deformação Eritrocítica/fisiologia , Eritrócitos/fisiologia , Eritrócitos/ultraestrutura , Adulto , Viscosidade Sanguínea/fisiologia , Elasticidade/fisiologia , Hemólise/fisiologia , Humanos , Técnicas In Vitro , Masculino , Estresse Mecânico , Adulto Jovem
14.
Invest Ophthalmol Vis Sci ; 62(15): 3, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34854885

RESUMO

Purpose: Fine focusing of light by the eye lens onto the retina relies on the ability of the lens to change shape during the process of accommodation. Little is known about the cellular structures that regulate elasticity and resilience. We tested whether Eph-ephrin signaling is involved in lens biomechanical properties. Methods: We used confocal microscopy and tissue mechanical testing to examine mouse lenses with genetic disruption of EphA2 or ephrin-A5. Results: Confocal imaging revealed misalignment of the suture between each shell of newly added fiber cells in knockout lenses. Despite having disordered sutures, loss of EphA2 or ephrin-A5 did not affect lens stiffness. Surprisingly, knockout lenses were more resilient and recovered almost completely after load removal. Confocal microscopy and quantitative image analysis from live lenses before, during, and after compression revealed that knockout lenses had misaligned Y-sutures, leading to a change in force distribution during compression. Knockout lenses displayed decreased separation of fiber cell tips at the anterior suture at high loads and had more complete recovery after load removal, which leads to improved whole-lens resiliency. Conclusions: EphA2 and ephrin-A5 are needed for normal patterning of fiber cell tips and the formation of a well-aligned Y-suture with fiber tips stacked on top of previous generations of fiber cells. The misalignment of lens sutures leads to increased resilience after compression. The data suggest that alignment of the Y-suture may constrain the overall elasticity and resilience of the lens.


Assuntos
Elasticidade/fisiologia , Cristalino/fisiologia , Receptor EphA2/fisiologia , Receptor EphA5/fisiologia , Animais , Fenômenos Biomecânicos , Forma Celular , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Confocal , Transporte Proteico , Transdução de Sinais/fisiologia
15.
BMC Urol ; 21(1): 163, 2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34837995

RESUMO

BACKGROUND: Hypospadias is a relatively common genital anomaly in humans, usually followed by inelastic dartos that causes penile chordee. Vascular endothelial growth factor (VEGF) is strongly linked to the viscoelasticity of tissues and their elastic phase. This study aimed to evaluate VEGF expressions in (1) fascia dartos between hypospadias and controls and (2) chordee severity. METHODS: This prospective cohort study involved 65 specimens from patients with hypospadias and ten specimens from controls. The samples were analyzed by quantitative real-time polymerase chain reaction (qPCR) for VEGF expression. RESULTS: The expressions of VEGF were not different between proximal and distal hypospadias patients and controls (fold change: distal - 0.25; fold change: proximal - 0.2; p = 0.664). The scaled expressions related to chordee severity were mild - 0.1; moderate 0.1; severe - 0.25 (p = 0.660). CONCLUSIONS: VEGF expressions might not affect the severity of hypospadias and chordee, implying the pathogenesis is complex involving many growth factors. Further study with a larger sample size is necessary to clarify and confirm our findings.


Assuntos
Elasticidade/fisiologia , Hipospadia/metabolismo , Pênis/fisiopatologia , RNA Mensageiro/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , Humanos , Hipospadia/fisiopatologia , Masculino , Pênis/anormalidades , Pênis/fisiologia , Fatores de Crescimento do Endotélio Vascular/genética
16.
Hum Cell ; 34(6): 1709-1716, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34312810

RESUMO

Mechanical stiffness is closely related to cell adhesion and rounding in some cells. In leukocytes, dephosphorylation of ezrin/radixin/moesin (ERM) proteins is linked to cell adhesion events. To elucidate the relationship between surface stiffness, cell adhesion, and ERM dephosphorylation in leukocytes, we examined the relationship in the myelogenous leukemia line, KG-1, by treatment with modulation drugs. KG-1 cells have ring-shaped cortical actin with microvilli as the only F-actin cytoskeleton, and the actin structure constructs the mechanical stiffness of the cells. Phorbol 12-myristate 13-acetate and staurosporine, which induced cell adhesion to fibronectin surface and ERM dephosphorylation, caused a decrease in surface stiffness in KG-1 cells. Calyculin A, which inhibited ERM dephosphorylation and had no effect on cell adhesion, did not affect surface stiffness. To clarify whether decreasing cell surface stiffness and inducing cell adhesion are equivalent, we examined KG-1 cell adhesion by treatment with actin-attenuated cell softening reagents. Cytochalasin D clearly diminished cell adhesion, and high concentrations of Y27632 slightly induced cell adhesion. Only Y27632 slightly decreased ERM phosphorylation in KG-1 cells. Thus, decreasing cell surface stiffness and inducing cell adhesion are not equivalent, but these phenomena are coordinately regulated by ERM dephosphorylation in KG-1 cells.


Assuntos
Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Proteínas do Citoesqueleto/metabolismo , Elasticidade/fisiologia , Leucemia Mieloide/patologia , Leucócitos/metabolismo , Leucócitos/fisiologia , Proteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/metabolismo , Actinas/metabolismo , Amidas/farmacologia , Adesão Celular/genética , Linhagem Celular Tumoral , Citocalasina D/farmacologia , Elasticidade/efeitos dos fármacos , Fibronectinas/metabolismo , Humanos , Leucemia Mieloide/metabolismo , Microvilosidades/efeitos dos fármacos , Microvilosidades/metabolismo , Ésteres de Forbol/farmacologia , Fosforilação/efeitos dos fármacos , Piridinas/farmacologia , Estaurosporina/farmacologia
17.
Invest Ophthalmol Vis Sci ; 62(7): 4, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34086046

RESUMO

Purpose: To investigate the relationship between biomechanical glaucoma factor (BGF) measured with Corvis ST and glaucomatous visual field (VF) progression, compared to corneal hysteresis (CH) measured with ocular response analyzer using a longitudinal dataset of primary open-angle glaucoma (POAG). The discriminative powers of BGF and CH were also compared using a cross-sectional dataset. Methods: The longitudinal dataset included 166 POAG eyes. The rate of VF change during the follow-up period was evaluated using the mean of 52 pointwise total deviations in the Humphrey 24-2 field test. Variables associated with the VF progression rate were identified from BGF, CH, age, baseline VF severity, and intraocular pressure during the VF follow-up period by identifying the optimal model. The cross-sectional dataset included 68 POAG eyes and 68 healthy eyes. Using this dataset, the area under the curve (AUC) values of the receiver-operating curve were compared between CH and BGF. Results: The optimal multivariate linear mixed model to describe the VF rate included age and CH, but not BGF. Between POAG and healthy eyes, CH was statistically different (P < 0.001), although this was not the case with BGF. The AUC values were 0.61 and 0.71 for BGF and CH, respectively (P = 0.027). Conclusions: CH, but not BGF, was associated with VF progression in POAG patients under treatment. BGF was not useful to discriminate POAG between treated and normal eyes.


Assuntos
Córnea , Elasticidade/fisiologia , Glaucoma de Ângulo Aberto , Transtornos da Visão , Campos Visuais , Fenômenos Biomecânicos , Córnea/patologia , Córnea/fisiopatologia , Paquimetria Corneana/métodos , Correlação de Dados , Progressão da Doença , Feminino , Glaucoma de Ângulo Aberto/diagnóstico , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Japão/epidemiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Tonometria Ocular/métodos , Transtornos da Visão/diagnóstico , Transtornos da Visão/etiologia , Transtornos da Visão/fisiopatologia , Testes de Campo Visual/métodos
18.
Sci Rep ; 11(1): 12479, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34127765

RESUMO

The objective of this study is to assess the change in the normal MD elasticity using shear wave elastography (SWE) through measuring the middle deltoid (MD) elasticity in healthy participants at various arm abduction (with bilateral arms at 0 degrees abduction and 90 degrees active abduction) and analyzing the factors affecting normal MD elasticity. Mean shear wave velocity (SWV) of the MD in healthy right-handed participants were evaluated using SWE at different arm abduction, and potential factors (gender, MD thickness, age, body mass index) affecting MD elasticity were analyzed. Different arm abduction positions of each participant were as follows: (i) 0° abduction of bilateral arm (L0° and R0°), (ii) 90° active abduction of bilateral arm (L90° and R90°). Mean SWV was significantly higher at L90° than L0°, higher at R90° than R0°, higher at R0° than L0°, and higher at R90° than L90° (all P < 0.0001). SWV was significantly higher in males at both L0° (P < 0.05) and R0° (P < 0.01) than in females. Neither MD thickness, age nor body mass index influenced MD elasticity. Reference ranges of normal MD elasticity were 2.4-3.1 m/s in males and 2.2-2.9 m/s in females at L0° and 2.5-3.3 m/s in males and 2.4-3.2 m/s in females at R0°, and were 4.9-6.7 m/s at L90°, 5.2-7.1 m/s at R90° for both males and females. SWE is a feasible technique to assess normal MD elasticity at various arm abduction. Our results suggest that normal MD elasticity at L0°, R0°, L90°, and R90° with SWE are different. Moreover, these reference ranges may serve as quantitative baseline measurements for assessment of normal MD elasticity in the future.


Assuntos
Braço/fisiologia , Músculo Deltoide/fisiologia , Técnicas de Imagem por Elasticidade , Elasticidade/fisiologia , Movimento , Adulto , Idoso , Braço/diagnóstico por imagem , Músculo Deltoide/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
19.
PLoS Comput Biol ; 17(5): e1008592, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34029312

RESUMO

During cell migration in confinement, the nucleus has to deform for a cell to pass through small constrictions. Such nuclear deformations require significant forces. A direct experimental measure of the deformation force field is extremely challenging. However, experimental images of nuclear shape are relatively easy to obtain. Therefore, here we present a method to calculate predictions of the deformation force field based purely on analysis of experimental images of nuclei before and after deformation. Such an inverse calculation is technically non-trivial and relies on a mechanical model for the nucleus. Here we compare two simple continuum elastic models of a cell nucleus undergoing deformation. In the first, we treat the nucleus as a homogeneous elastic solid and, in the second, as an elastic shell. For each of these models we calculate the force field required to produce the deformation given by experimental images of nuclei in dendritic cells migrating in microchannels with constrictions of controlled dimensions. These microfabricated channels provide a simplified confined environment mimicking that experienced by cells in tissues. Our calculations predict the forces felt by a deforming nucleus as a migrating cell encounters a constriction. Since a direct experimental measure of the deformation force field is very challenging and has not yet been achieved, our numerical approaches can make important predictions motivating further experiments, even though all the parameters are not yet available. We demonstrate the power of our method by showing how it predicts lateral forces corresponding to actin polymerisation around the nucleus, providing evidence for actin generated forces squeezing the sides of the nucleus as it enters a constriction. In addition, the algorithm we have developed could be adapted to analyse experimental images of deformation in other situations.


Assuntos
Movimento Celular/fisiologia , Núcleo Celular/fisiologia , Modelos Biológicos , Actinas/metabolismo , Algoritmos , Animais , Fenômenos Biomecânicos , Núcleo Celular/ultraestrutura , Forma Celular/fisiologia , Biologia Computacional , Simulação por Computador , Células Dendríticas/citologia , Células Dendríticas/fisiologia , Elasticidade/fisiologia , Camundongos , Microtecnologia , Imagem com Lapso de Tempo
20.
Medicine (Baltimore) ; 100(18): e25826, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33950991

RESUMO

ABSTRACT: There is evidence that serum 25-hydroxyvitamin D [25-(OH) D] levels may be associated with cardiovascular disease and its risk factors. This study aimed to investigate the relationship between 25-(OH) D levels and blood pressure (BP), blood lipids, and arterial elasticity in middle-aged and elderly cadres in China.In this retrospective study, we included 401 civil servants and cadres aged >42 years who underwent medical examinations at Guiyang Municipal First People's Hospital, China in 2018. The participants were assigned to deficiency (≤20 ng/mL), insufficiency (20-30 ng/mL), and sufficiency (≥30 ng/mL) groups according to 25-(OH) D levels in their blood. Demographics, brachial-ankle pulse wave velocity (baPWV), BP, ankle-brachial index (ABI), and blood lipids were compared among groups. The associations between 25-(OH) D and other parameters were evaluated using linear regression analysis.Median (range) 25-(OH) D levels in the deficiency (n = 162), insufficiency (n = 162), and sufficiency (n = 77) groups were 15.32 (2.93-19.88), 25.12 (20.07-29.91), and 33.91 (30.23-82.42) ng/mL, respectively. There were significant differences in systolic BP, pulse pressure, baPWV (left and right sides), ABI (left side), high-density lipoprotein-cholesterol, and triglycerides (TGs; all P < .05) among groups. Multivariate linear regression revealed that TG, left baPWV, and right baPWV were significantly negatively correlated with 25-(OH) D levels (all P < .05).In this study, 25-(OH) D levels were found to be associated with TG, left baPWV, and right baPWV values. 25-(OH) D deficiency may be associated with reduced arterial elasticity.


Assuntos
Doenças Cardiovasculares/epidemiologia , Deficiência de Vitamina D/epidemiologia , Vitamina D/análogos & derivados , Adulto , Idoso , Índice Tornozelo-Braço , Artérias/fisiopatologia , Pressão Sanguínea/fisiologia , Doenças Cardiovasculares/fisiopatologia , China/epidemiologia , Elasticidade/fisiologia , Feminino , Empregados do Governo/estatística & dados numéricos , Fatores de Risco de Doenças Cardíacas , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Análise de Onda de Pulso , Estudos Retrospectivos , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/diagnóstico
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