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Journal of Biomedical Engineering ; (6): 87-94, 2023.
Article in Chinese | WPRIM | ID: wpr-970677


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.

Female , Humans , Cisplatin/pharmacology , Elasticity/physiology , Etoposide , Extracellular Matrix/physiology , Ovarian Neoplasms/metabolism , RNA, Long Noncoding/metabolism
Int. j. morphol ; 40(3): 839-850, jun. 2022. ilus, tab
Article in English | LILACS | ID: biblio-1385657


SUMMARY: Several studies have shown beneficial effects of platelet-rich plasma. However, there are very few studies investigating the effectiveness of PRP in the neck region. We aimed to assess the efficacy of PRP injection for neck rejuvenation in females aged 40-55. Fifty-two female consecutive participants had PRP injected and roller applied in three sessions at 3-week intervals. Evaluations were blindly performed by comparing the improvements from the pre- to post-application assessments of anatomical measurements of the neck area based on before and after photography of the participants by two anatomists and three medical aesthetic doctors. The Fitzpatrick Skin Scale, Fitzpatrick Goldman Scale, Wrinkle Assessment Scale (Dedo classification system) and patient satisfaction scale were used for assessment. Additionally, skin stiffness and elasticity, cervicomental angle and jawline angle measurements were performed to analyze anatomical changes in the neck area. The study enrolled 52 volunteers with a mean age of 48.60±5.35 years, mean body weight of 63.21±8.43 kg and mean height of 163.25±4.56 cm. Significant differences were found in the elasticity, jawline angle, cervicomental angle, wrinkling, elasticity G and patient satisfaction scores before and after the treatment. When the results of anatomical parameters and scales are compared, it was revealed that PRP is effective in neck rejuvenation.

RESUMEN: Varios investigaciones han demostrado los efectos beneficiosos del plasma rico en plaquetas. Sin embargo, existen muy pocos estudios que investiguen la efectividad del PRP en la región del cuello. Nuestro objetivo fue evaluar la eficacia de la inyección de PRP para el rejuvenecimiento del cuello en mujeres de 40 a 55 años. A cincuenta y dos mujeres participantes consecutivas se les inyectó PRP y se les aplicó rodillo en tres sesiones a intervalos de 3 semanas. Las evaluaciones se realizaron a ciegas comparando las mejoras de las evaluaciones previas y posteriores a la aplicación de las medidas anatómicas del área del cuello basadas en fotografías de antes y después de los participantes realizadas por dos anatomistas y tres médicos especialistas en cirugía estética. Para la evaluación se utilizaron la escala de piel de Fitzpatrick, la escala de Fitzpatrick Goldman, la escala de evaluación de arrugas (sistema de clasificación Dedo) y la escala de satisfacción del paciente. Además, se realizaron mediciones de rigidez y elasticidad de la piel, ángulo cervicomentoniano y ángulo de la línea de la mandíbula, para analizar los cambios anatómicos en el área del cuello. El estudio inscribió a 52 voluntarios con una edad media de 48,60±5,35 años, un peso corporal medio de 63,21±8,43 kg y una altura media de 163,25±4,56 cm. Se encontraron diferencias significativas en las puntuaciones de elasticidad, ángulo mandibular, ángulo cervicomentoniano, arrugas, elasticidad G y satisfacción del paciente antes y después del tratamiento. Cuando se compararon los resultados de los parámetros anatómicos y las escalas, se reveló que el PRP es eficaz en el rejuvenecimiento del cuello.

Humans , Female , Adult , Middle Aged , Rejuvenation , Elasticity , Platelet-Rich Plasma , Neck , Skin Aging
Rev. bras. oftalmol ; 81: e0036, 2022. tab, graf
Article in English | LILACS | ID: biblio-1376779


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.

Humans , Tonometry, Ocular/instrumentation , Tonometry, Ocular/methods , Biomechanical Phenomena , Cornea/anatomy & histology , Cornea/physiology , Intraocular Pressure/physiology , Glaucoma/physiopathology , Ocular Hypertension/physiopathology , Diagnostic Techniques, Ophthalmological/instrumentation , Elasticity/physiology , Models, Theoretical
Chinese Journal of Contemporary Pediatrics ; (12): 566-571, 2022.
Article in Chinese | WPRIM | ID: wpr-928644


OBJECTIVES@#To study the application of three-dimensional speckle-tracking imaging in evaluating left ventricular systolic function and its correlation with peripheral arterial elasticity in children with simple obesity.@*METHODS@#Random sampling combined with convenience sampling was used to obtain research samples, and then the samples were divided into an obesity group (23 cases), an overweight group (21 cases), and a normal group (24 cases). Three-dimensional speckle-tracking imaging was used to measure the global longitudinal strain (GLS), global radial strain (GRS), and global circumferential strain (GCS) of the left ventricle. An automatic arteriosclerosis tester was used to measure ankle-brachial index (ABI) and brachial-ankle pulse wave velocity (baPWV). These parameters were compared among the three groups. The correlation of three-dimensional speckle-tracking parameters with ABI and baPWV was evaluated.@*RESULTS@#There were no significant differences in GLS, GRS, and GCS between the obesity and normal groups (P>0.05). The overweight group had a significantly higher GLS than the normal group [(-24±7) vs (-19±12), P<0.05]. The obesity and overweight groups had a significantly lower ABI than the normal group [(1.00±0.09)/(1.09±0.13) vs (2.25±0.13), P<0.05). The obesity group had a significantly higher baPWV than the normal group [(978±109) vs (905±22), P<0.05]. In the children with obesity, GLS was positively correlated with baPWV (r=0.516, P<0.05) , but not correlated with ABI (P>0.05), and GCS and GRS had no significant correlation with ABI or baPWV (P>0.05).@*CONCLUSIONS@#There are varying degrees of changes in left ventricular systolic function and peripheral arterial elasticity in children with simple obesity, and there is a certain correlation between them.

Child , Humans , Ankle Brachial Index , Echocardiography, Three-Dimensional/methods , Elasticity , Obesity , Overweight , Prospective Studies , Pulse Wave Analysis
Journal of Biomedical Engineering ; (6): 1127-1132, 2022.
Article in Chinese | WPRIM | ID: wpr-970650


The radial artery pulse wave contains a wealth of physiological and pathological information about the human body, and non-invasive studies of the radial artery pulse wave can assess arterial vascular elasticity in different age groups.The piezoelectric pulse wave transducers were used to non-invasively acquire radial artery pulse waves at different contact pressures in young and middle-aged and elderly populations. The radial artery waveforms were decomposed using a triangular blood flow model fitting method to obtain forward and reflected waves and calculate reflection parameters. Finally a correlation analysis and regression analysis of the contact pressure Psensor with the reflection parameters was carried out. The results showed that the reflection parameters RM, RI and Rd had a strong negative correlation with Psensor in both types of subjects, and the correlation coefficients and slopes of the regression curves were significantly different between the two types of subjects (P<0.05). Based on the results of this study, excessive contact pressure on the transducer should be avoided when detecting radial artery reflection waves in clinical practice. The results also show that the magnitude of the slope of the regression curve between the reflection parameters and the transducer contact pressure may be a potentially useful indicator for quantifying the elastic properties of the vessel.

Middle Aged , Aged , Humans , Blood Pressure/physiology , Arteries , Blood Flow Velocity/physiology , Elasticity , Pulse Wave Analysis , Radial Artery/physiology
China Journal of Chinese Materia Medica ; (24): 2244-2250, 2022.
Article in Chinese | WPRIM | ID: wpr-928165


The present study explored the correlation of coronary heart disease(CHD) with blood stasis syndrome in postmenopausal women with artery elasticity and endothelial function indexes and evaluated the diagnostic efficacy of the prediction model via logistic regression and receiver operating characteristic(ROC) curve model. A retrospective comparison was made between 366 postmenopausal CHD patients from August 1, 2020, to September 30, 2021, in the Department of Cardiology of Integrated Traditional Chinese and Western Medicine of China-Japan Friendship Hospital, who were divided into the blood stasis syndrome group(n=196) and the non-blood stasis syndrome group(n=170). General clinical characteristics of the two groups were compared. Multivariate logistic regression analysis was used to probe the correlation of CHD with blood stasis syndrome in postmenopausal women with brachial-ankle pulse wave velocity(baPWV), ankle-brachial index(ABI), and flow-mediated dilatation(FMD), and the ROC curve was drawn to evaluate the diagnostic efficiency of the prediction model. Multivariate logistic regression analysis showed that the correlation coefficients of CHD with blood stasis syndrome in postmenopausal women with baPWV, ABI, and FMD were 1.123, 0.109, and 0.719, respectively(P=0.004, P=0.005, P<0.001),and the regression equation for predicting probability P was P=1/[1+e~(-(3.131+0.116×baPWV-2.217×ABI-0.330×FMD))]. ROC curve analysis suggested that in the context of baPWV≥19.19 m·s~(-1) or ABI≤1.22 or FMD≤9.7%, it was of great significance to predict the diagnosis of CHD with blood stasis syndrome in postmenopausal women. The AUC of baPWV, ABI, FMD, and prediction probability P was 0.763, 0.607, 0.705, and 0.836, respectively. The AUC of prediction probability P was higher than that of each index alone(P<0.001), and the sensitivity and specificity were 0.888 and 0.647, respectively. The results demonstrate that baPWV, ABI, and FMD are independently correlated with CHD with blood stasis syndrome in postmenopausal women, and show certain independent predictive abilities(P<0.05). The combined evaluation of the three possesses the best diagnostic efficiency.

Female , Humans , Ankle Brachial Index , Brachial Artery , Coronary Disease/diagnosis , Elasticity , Logistic Models , Postmenopause , Pulse Wave Analysis , ROC Curve , Retrospective Studies
Braz. dent. j ; 32(4): 55-61, July-Aug. 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1345512


Abstract The purpose of this in vitro study was to evaluate the force decrease of different elastomeric chains after different times: initial, 10 minutes, 1 day, 28 days and after mechanical brushing. Twenty orthodontic elastomeric chains segments were utilized for each commercial brand. Initially, the elastomeric chain of 15mm long were immediate stretched up to 20 mm in an Instron and the force was measured in gf. After all specimens were placed stretched on rectangular acrylic jigs with distance of 20 mm, immersed in deionized water at 37oC for 10 minutes and the force (gf) was measured again. Five test measurements of remaining force were made at the following time intervals: initial, 10 minutes, 1 day, 28 days and mechanical brushing. After 28 days, the acrylic plates with the specimens were adapted in the mechanical brushing machines (MSCT 3) and the elastomeric chains were submitted to mechanical brushing and the force (gf) measure again. The force (gf) was submitted to mixed-model ANOVA and Sidak post-hoc test (α=0.05). A statistically significant reduction in the force was found for all orthodontic elastomeric chain types after 1 day, 28 days and mechanical brushing (p<0.05). Morelli and 3M Unitek elastomeric chains showed significantly higher force than Abzil and GAC (p<0.05) after 1 day, 28 days and mechanical brushing. In conclusion, the force delivered by all elastomeric chains decayed rapidly over time. Morelli and 3M Unitek elastomeric chains consistently had a significantly greater force after mechanic brushing, while GAC the lowest.

Resumo O objetivo deste estudo in vitro foi avaliar a redução da força de diferentes cadeias elastoméricas após diferentes tempos: inicial, 10 minutos, 1 dia, 28 dias e após escovação mecânica. Vinte segmentos de cadeias elastoméricas ortodônticas foram utilizadas para cada marca comercial. Inicialmente, a cadeia elastomérica de 15 mm de comprimento foi esticada imediatamente até 20 mm na Instron e a força foi medida em (gf). Após, todas as amostras foram adaptadas esticadas em placas retangulares de acrílico na distância de 20 mm, imersas em água deionizada a 37o C por 10 minutos e a força (gf) foi medida novamente. Cinco medidas de força foram feitas nos seguintes intervalos de tempo: inicial, 10 minutos, 1 dia, 28 dias e após a escovação mecânica. Após 28 dias, as placas de acrílico com as amostras foram adaptadas na máquina de escovação (MSCT 3) e as cadeias elastoméricas foram submetidas a escovação mecânica e a medida de força (gf) novamente. Os dados da força (gf) foram submetidos a ANOVA modelo misto e teste post-hoc de Sidak (α = 0,05). Uma redução estatisticamente significativa na força foi encontrada para todos os tipos de cadeia elastomérica ortodôntica após 1 dia, 28 dias e escovação mecânica (p<0,05). As cadeias elastoméricas Morelli e 3M Unitek apresentaram força significativamente superior em relação a Abzil e GAC (p<0,05) após 1 dia, 28 dias e escovação mecânica. Em conclusão, a força distribuída por todas as cadeias elastoméricas decaiu rapidamente com o tempo. As cadeias elastoméricas Morelli e 3M Unitek consistentemente tiveram uma força significativamente maior após a escovação mecânica, enquanto GAC a mais baixa.

Orthodontic Appliances , Elastomers , Stress, Mechanical , Toothbrushing , Materials Testing , Elasticity
Rev. bras. ciênc. mov ; 29(1): [1-15], jan.-mar. 2021. tab, ilus
Article in Portuguese | LILACS | ID: biblio-1348199


: A cervicobraquialgia (CB) é caracterizada por uma dor com origem em diferentes níveis estruturais da coluna cervical baixa (C3- C7), com irradiação bilateral ou unilateral para o membro superior. Considerando as causas e consequências advindas da CB, novas modalidades de tratamento têm sido propostas na tentativa de promover intervenções efetivas. Entre os procedimentos fisioterapêuticos encontram-se as técnicas de terapia manual como liberação miofascial, quiropraxia, mobilização articular, estabilização segmentar e a mobilização neural (MN) que procura restabelecer a função do tecido neural, sua condução elétrica, elasticidade, movimento e fluxo axoplasmático. Sendo assim, o objetivo do estudo foi avaliar sistematicamente as evidências sobre o efeito da MN no tratamento da dor em indivíduos com CB. A busca bibliográfica foi realizada no período entre Novembro de 2018 a Junho de 2019, sem limite de ano de publicação, nas bases de dados: PEDro, PubMed, Biblioteca Virtual em Saúde (Lilacs, Scielo e Medline) e Cochrane Library. A análise foi restrita aos ensaios clínicos randomizados. Para a análise etodológica dos artigos aptos a inclusão, foi utilizada a escala PEDro. Foi encontrado um total de 38 artigos. Após remoção de duplicatas, 14 artigos foram elegidos por resumo, 8 artigos foram recuperados para leitura completa e analisados quanto a sua adequação, dos quais 3 foram excluídos por não cumprirem os critérios de elegibilidade, ao fim 5 artigos foram incluídos na revisão. Houve redução significativa da dor, em pacientes tratados com MN. Considerando os resultados obtidos nesta revisão, foi possível concluir que a MN demonstra ser eficaz na redução da dor presente na CB. Embora os estudos mostrem que os resultados da MN como tratamento da CB são significativamente inferiores ao efeito do Ibuprofeno, deve-se ter em consideração as consequências a longo prazo para a saúde sobre a utilização de anti- inflamatórios orais.(AU)

Cervicobrachialgia (CB) is characterized by pain originating from different structural levels of the lower cervical spine (C3-C7), w ith bilateral or unilateral irradiation to the upper limb. Considering the causes and consequences of CB, new treatment modalities have been proposed in an attempt to promote effective interventions. Among the physical therapy procedures are manual therapy techniques such as myofascial release, chiropractic, joint mobilization, segmental stabilization and neural mobilization (NM) that seeks to restore the function of neural tissue, its electrical conduction, elasticity, movement and ax oplasmic flow . Thus, the objective of the study w as to evaluate systematically evaluate the evidence on the effect of NM on pain management in individuals w ith CB. The bibliographic search w as performed from November 2018 to June 2019, w ithout limit of year of publication, in the databases: PEDro, PubMed, Virtual Health Library (Lilacs, Scielo and Medline) and Cochrane Library. The analysis w as restricted to randomized controlled trials. For the methodological analysis of the articles eligible for inc lusion, the PEDro scale w as used. A total of 38 articles w ere found. After removal of duplicates, 14 articles w ere elected by abstract, 8 articles w ere retrieved for full reading and analyzed for suitability, of w hich 3 w ere excluded for not meeting eligibility c riteria, at the end 5 articles w ere included in the review . There was a significant pain reduction in patients treated w ith NM. Considering the results obtained in this review , it w as concluded that NM demonstrates to be effective in reducing pain present in CB. Although studies show that the results of NM as a treatment for CB are significantly low er than the effect of ibuprofen, consideration should be given to the long-term health consequences about the utilization of oral anti-inflammatory drugs.(AU)

Humans , Male , Female , Adult , Middle Aged , Aged , Pain , Pain Management , Neural Conduction , Neuralgia , Physical Education and Training , Chiropractic , Physical Therapy Modalities , Manipulation, Spinal , Heat Conduction , Musculoskeletal Manipulations , Upper Extremity , Elasticity , Joints
Rev. colomb. gastroenterol ; 36(1): 58-64, ene.-mar. 2021. tab, graf
Article in Spanish | LILACS | ID: biblio-1251522


Resumen Introducción: la elastografía en tiempo real, 2D-SWE (Supersonic), es una prueba no invasiva que se utiliza para determinar la elasticidad del hígado y, de esa forma, calcular el grado de fibrosis hepática. En Colombia, la prueba se introdujo en 2016 y no existen hasta el momento estudios del comportamiento de la prueba en todos los pacientes hepáticos, solo se han publicado en pacientes sanos y cirróticos. Objetivo: analizar la experiencia de la aplicación de la elastografía en tiempo real, en sujetos atendidos en el centro de enfermedades hepáticas y digestivas de Bogotá, Colombia. Materiales y métodos: estudio descriptivo retrospectivo de una cohorte de sujetos atendidos entre marzo de 2016 y julio de 2017. Se realizó una historia clínica completa y una prueba de elastografía en tiempo real (Supersonic). Resultados: se incluyeron 654 sujetos, con una mediana de edad de 55 años (rango intercuartílico [RIC]: 45-64). La mediana de valores de fibrosis expresada en kilopascales (kPs) fue de 8,3, con un promedio de 5 mediciones. Se observó una diferencia significativa en el grado de fibrosis entre los grupos de edad y en relación con el diagnóstico final, donde se evidenció una mayor fibrosis en el grupo de enfermedades colestásicas (autoinmune, colangitis biliar primaria [CBP] y superposición autoinmune-CBP). La tasa global de fracaso fue menor al 1%. Conclusiones: es la primera descripción del comportamiento de la prueba a nivel nacional. Los valores de rigidez hepática observados en los diferentes estadios demuestran la utilidad de la prueba para la determinación de la fibrosis hepática en pacientes con diferentes patologías.

Abstract Introduction: Real-time two-dimensional shear wave elastography (2D-SWE) (Supersonic Imagine SA), is a non-invasive test used to determine liver elasticity and calculate the degree of liver fibrosis. In Colombia, this test was introduced in 2016 and, to date, no study has tested its behavior in all liver patients, only in healthy and cirrhotic patients. Objective: To analyze the experience of real-time elastography implementation in subjects treated at the Centro de Enfermedades Hepáticas y Digestivas in Bogotá, Colombia. Materials and methods: This is a retrospective descriptive study of a cohort of subjects treated between March 2016 and July 2017. A complete medical report and a real-time elastography (Supersonic) test were performed. Results: 654 subjects were included, with a median age of 55 years (interquartile range [IQR]: 45-64). The median fibrosis values expressed in kilopascals (kPs) were 8.3, with an average of 5 measurements. There was a significant difference in the degree of fibrosis between the age groups and in relation to the final diagnosis, where there was a greater fibrosis in the cholestatic disease group (autoimmune, primary biliary cholangitis [PBC], and overlap). The overall failure rate was less than 1%. Conclusions: This is the first description of this test behavior in the country. Hepatic stiffness values observed in the different stages demonstrate the usefulness of the test to establish the degree of liver fibrosis in patients with multiple diseases.

Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Fibrosis , Elasticity Imaging Techniques , Liver , Medical Records , Elasticity , Research Report , Methods
Dental press j. orthod. (Impr.) ; 26(2): e211945, 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1249705


ABSTRACT Objective: This paper aims to verify the thermodynamic, mechanical and chemical properties of CuNiTi 35ºC commercial wires. Methods: Forty pre-contoured copper-nickel-titanium thermodynamic 0.017 x 0.025-in archwires with an Af temperature of 35°C were used. Eight wires from five different manufacturers (American Orthodontics® [G1], Eurodonto® [G2], Morelli® [G3], Ormco® [G4] and Orthometric® [G5]) underwent cross-sectional dimension measurements, tensile tests, SEM-EDS and differential scanning calorimetry (DSC) tests. Parametric tests (One-way ANOVA and Tukey post-test) were used, with a significance level of 5%, and Pearson's correlation coefficient test was performed between the Af and chemical elements of the wires. All sample tests and statistical analyses were double-blinded. Results: All wires presented standard dimensions (0.017 x 0.025-in) and superelastic behavior, with mean plateau forces of: G1 = 36.49N; G2 = 27.34N; G3 = 19.24 N; G4 = 37.54 N; and G5 = 17.87N. The Af means were: G1 = 29.40°C, G2 = 29.13°C and G3 = 31.43°C, with p>0.05 relative to each other. G4 (32.77°C) and G5 (35.17°C) presented statistically significant differences between each other and among the other groups. All samples presented Ni, Ti, Cu and Al in different concentrations. Conclusions: The chemical concentration of the elements that compose the alloy significantly influenced the thermodynamic and mechanical properties.

RESUMO Objetivo: O presente artigo teve como objetivo verificar as propriedades termodinâmicas, mecânicas e químicas de fios CuNiTi 35°C comerciais. Métodos: Foram utilizados 40 arcos termodinâmicos pré-contornados de cobre-níquel-titânio de 0,017" x 0,025" e temperatura Af de 35°C. Oito fios de cinco fabricantes diferentes (American Orthodontics® [G1], Eurodonto® [G2], Morelli® [G3], Ormco® [G4] e Orthometric® [G5]) foram submetidos a medições de suas secções transversais, testes de tração, MEV-EDS e calorimetria diferencial (DSC). Foram utilizados testes paramétricos (One-way ANOVA e pós-teste de Tukey), com nível de significância de 5%, e foi realizado o teste do coeficiente de correlação de Pearson entre a temperatura Af e os elementos químicos dos fios. Todos os testes das amostras e análises estatísticas foram duplo-cegos. Resultados: Todos os fios apresentavam dimensões padronizadas (0,017" x 0,025") e comportamento superelástico, com forças médias de platô de G1 = 36,49 N; G2 = 27,34 N; G3 = 19,24 N; G4 = 37,54 N; e G5 = 17,87 N. As médias de Af foram: G1 = 29,40°C, G2 = 29,13°C e G3 = 31,43°C, com p> 0,05 entre si. G4 (32,77°C) e G5 (35,17°C) apresentaram diferenças estatisticamente significativas entre si e entre os demais grupos. Todas as amostras apresentaram Ni, Ti, Cu e Al em diferentes concentrações. Conclusões: A concentração química dos elementos que compõem a liga influenciou significativamente as propriedades termodinâmicas e mecânicas.

Orthodontic Wires , Dental Alloys , Stress, Mechanical , Titanium , Materials Testing , Cross-Sectional Studies , Elasticity
Rev. cuba. med. mil ; 49(3): e511, jul.-set. 2020. fig
Article in Spanish | LILACS, CUMED | ID: biblio-1144485


Introducción: Para definir una adecuada estrategia terapéutica en el cáncer de recto es preciso una correcta estadificación. El ultrasonido endoscópico es un método de estadiaje preciso que define la profundidad del tumor y el estado nodal. En los tumores tratados con radioterapia disminuye su rentabilidad por la fibrosis que se origina en la pared rectal; indistinguible de los elementos de malignidad. La elastografía brinda la posibilidad de resolver esta limitación. Objetivo: Ofrecer una actualización sobre la elastografía por ultrasonido endoscópico en el diagnóstico del paciente con tumor rectal. Desarrollo: La elastografía se basa en las alteraciones que en la elasticidad del tejido inducen la fibrosis y el cáncer. Determina si un tejido es maligno o benigno mediante el análisis de su dureza. Se obtienen imágenes que se expresan en un mapa de colores superpuestas a la imagen convencional del ultrasonido endoscópico. Muchas investigaciones demuestran su elevada sensibilidad y especificidad en tumores de páncreas y ganglios linfáticos, algunas en tumores de esófago, sin embargo muy pocas en el cáncer rectal. Conclusiones: La elastografía ha mejorado el diagnóstico y seguimiento oncológico del paciente con tumor rectal(AU)

Introduction: To define an adequate therapeutic strategy in rectal cancer, a correct staging is necessary. For this, advanced diagnostic means have been developed to evaluate the rectal wall. Endoscopic Ultrasound a fundamental technique; combines endoscopic image with ultrasound; in tumors treated with radiotherapy, its profitability decreases due to fibrosis that originates in the rectal wall; indistinguishable from the elements of malignancy. Elastography offers the possibility of resolving this limitation. Objective: To offer an update on elastography by endoscopic ultrasound in the diagnosis of the patient with rectal tumor. Development: Elastography is based on the alterations that fibrosis and cancer induce in the elasticity of the tissue. Determine if a tissue is malignant or benign by analyzing its hardness. Images are obtained that are expressed on a color map superimposed on the conventional endoscopic ultrasound image. Many investigations demonstrate its high sensitivity and specificity in tumors of the pancreas and lymph nodes, some in esophageal tumors, however very few in rectal cancer. Conclusions: Elastography has improved the diagnosis and oncological follow-up of the patient with rectal tumor(AU)

Humans , Male , Female , Rectal Neoplasms/diagnostic imaging , Elasticity/radiation effects , Elasticity Imaging Techniques , Lymph Nodes
Korean Journal of Radiology ; : 384-385, 2020.
Article in English | WPRIM | ID: wpr-810974


No abstract available.

Elasticity Imaging Techniques , Elasticity , Tendons , Ultrasonography
Chinese Journal of Medical Instrumentation ; (6): 384-389, 2020.
Article in Chinese | WPRIM | ID: wpr-942746


To satisfy the daily demand of skin condition maintenance, make non-invasive real-time detection, and get proper quantitative evaluation of skin viscoelasticity parameters at the same time, a portable non-invasive detection system to acquire real-time skin tissue viscoelasticity is developed. The system relies mainly on a single-degree-of-freedom forced vibration model, with spring-damp-mass, and on dynamic micro indentation method. The experiment is conducted on two kinds of springs, and on pigskin tissues as well, the system's suitability, accuracy and stability are confirmed. The skin viscoelasticity detection in vivo is also carried out on 20 subjects with different ages, the differences of skin viscoelasticity in various parts of the body are investigated, and the correlations between age and skin viscoelasticity are clarified.

Humans , Elasticity , Skin , Skin Physiological Phenomena , Time , Viscosity
Rev. bras. cir. cardiovasc ; 34(4): 451-457, July-Aug. 2019. tab, graf
Article in English | LILACS | ID: biblio-1020508


Abstract Objective: To evaluate the aortic wall elasticity using the maximal rate of systolic distension (MRSD) and maximal rate of diastolic recoil (MRDR) and their correlation with the aortic size index (ASI). Methods: Forty-eight patients with thoracic aortic aneurysm were enrolled in this study. A standard magnetic resonance imaging (MRI) protocol was used to calculate MRSD and MRDR. Both MRSD and MRDR were expressed as percentile of maximal area/10-3 sec. ASI (maximal aortic diameter/body surface area) was calculated. A correlation between MRSD, MRDR, ASI, and the patient's age was performed using regression plot. Results: A significant correlation between MRSD (t=-4,36; r2=0.29; P≤0.0001), MRDR (t=3.92; r2=0.25; P=0.0003), and ASI (25±4.33 mm/m2; range 15,48-35,14 mm/m2) is observed. As ASI increases, aortic MRSD and MRDR decrease. Such inverse correlation between MRSD, MRDR, and ASI indicates increased stiffness of the ascending aorta. A significant correlation between the patient's age and the decrease in MRSD and MRDR is observed. Conclusion: MRSD and MRDR are significantly correlated with ASI and the patient's age. They seem to describe properly the increasing stiffness of aortas. These two new indexes provide a promising, accessible, and reproducible approach to evaluate the biomechanical property of the aorta.

Humans , Male , Female , Adult , Middle Aged , Aged , Aorta/physiopathology , Magnetic Resonance Imaging , Aortic Aneurysm, Thoracic/diagnostic imaging , Aortic Dissection/diagnostic imaging , Systole/physiology , Diastole/physiology , Dilatation, Pathologic , Elasticity
urol. colomb. (Bogotá. En línea) ; 28(3): 204-208, 2019. ilus
Article in Spanish | LILACS, COLNAL | ID: biblio-1402385


La estrechez de la uretra es una patología con una prevalencia del 0,6% de la población El estándar de oro establecido para su manejo es la uretroplastia con tasas de éxito variables de hasta el 90% al 95%. El stent uretral surgió en 1988 fabricado con malla de acero inoxidable. Los resultados obtenidos demostraron las complicaciones severas de su implantación. En el 2008 se introdujo el stent Allium producido en Israel con propiedades diferentes como elasticidad y flexibilidad. Puede utilizarse en diferentes entidades como estrechez de uretra bulbar, hiperplasia de próstata y la estenosis de la unión uretrovesical. Recientemente este Stent se está comercializando en Colombia, por lo cual consideramos importante revisar la literatura mundial, las complicaciones e indicaciones reales y así intentar evitar el uso inapropiado de esos dispositivos. Realizamos una Revisión de la literatura en PubMed y ClinicalKey incluyendo los términos, "Stent", "Allium" y "Urethral", incluyendo articulos en inglés y en español. Se encontraron 4 artículos retrospectivos en poblaciones heterogéneas con tasas de éxito inferiores a la cirugía reconstructiva. No se encontraron estudios comparativos. Las indicaciones actuales para colocar un stent uretral podrían ser pacientes en quienes no se puede realizar uretroplastia, o en quienes el manejo endoscópico de la uretra posterior no haya sido efectivo. También pu

Urethral stricture disease is a pathology with a prevalence of 0.6% of the population The gold standard established for its management is urethroplasty with variable success rates of up to 90% to 95%. The urethral stent arose in 1988 manufactured with stainless steel mesh. The results obtained showed the severe complications of its implantation. In 2008, the Allium stent was produced in Israel with different properties such as elasticity and flexibility. It can be used in different entities such as bulbar urethra strictures, prostatic hyperplasia and stenosis of the urethrovesical junction. Recently this Stent is being marketed in Colombia, which is why we consider important to review the literature, complications and real indications and thus try to avoid the inappropriate use of these devices. We conducted a literature review in PubMed and ClinicalKey including the terms "Stent", "Allium" and "Urethral", including articles in English and Spanish. We found 4 retrospective articles in heterogeneous populations with success rates lower than reconstructive surgery. No comparative studies were found. Current indications to place a stent urethral could be patients in whom urethroplasty cannot be performed, or in patients in which endoscopic management of the posterior urethra has not been effective. It can also be an alternative for patients with permanent bladder catheter due to prostatic hyperplasia not suitable for surgery

Humans , Male , Urethral Stricture , Catheters , Prostate , Prostatic Hyperplasia , Urinary Bladder , Constriction, Pathologic , Plastic Surgery Procedures , Elasticity
Ultrasonography ; : 2-12, 2019.
Article in English | WPRIM | ID: wpr-731046


Shear wave elastography (SWE) is an emerging technology that provides information about the inherent elasticity of tissues by producing an acoustic radiofrequency force impulse, sometimes called an “acoustic wind,” which generates transversely-oriented shear waves that propagate through the surrounding tissue and provide biomechanical information about tissue quality. Although SWE has the potential to revolutionize bone and joint imaging, its clinical application has been hindered by technical and artifactual challenges. Many of the stumbling blocks encountered during musculoskeletal SWE imaging are readily recognizable and can be overcome, but progressive advances in technology and a better understanding of image acquisition are required before SWE can reliably be used in musculoskeletal imaging.

Acoustics , Elasticity , Elasticity Imaging Techniques , Joints , Muscles , Musculoskeletal System , Tendons , Ultrasonography
Journal of Korean Physical Therapy ; (6): 176-183, 2019.
Article in English | WPRIM | ID: wpr-765444


PURPOSE: The purpose of this study was to investigate the short term effects of ASEJ (ankle strengthening with emphasis on jumping) for 3weeks on strength, mechanical properties, and balance and to compare the balance with and without HH(high-heel) condition. METHODS: ASEJ (a combined exercise of squat, heel raise up, and jumping) were performed for the subjects in 11 female ankle instability young females (21.7±2.0 yrs Cumberland ankle instability score 19±6.5). To investigate the effect of ASEJ, investigator used dynamometer for measuring strength, MyotonPRO for measuring mechanical properties(tone, stiffness, and elasticity of the muscles), I-Balance test for static balance, and Y-balance test for dynamic balance between the condition with and without HH condition. All data were normally distributed and analyzed using the SPSS 22.0 statistical program. Comparing pre- and post-intervention and the condition with and without HH conditions data were examined using the paired t-test. The level of significance was chosen as 0.05 for all the analyses. RESULTS: 3wks of ASEJ would strengthen leg muscles and increasing muscle tone and stiffness in most muscles however there was decreasing muscle elasticity of gastrocnemious. In addition, the ASEJ improves the static balance for ankle instability young females and increases the dynamic balance when wearing the heels especially. CONCLUSION: the ASEJ could recommend to improve the strength and balance for ankle instability young females. Also, measuring the balance with HH conditions well represents the risk of ankle damage in female.

Female , Humans , Ankle , Elasticity , Heel , Leg , Muscles , Research Personnel
Journal of Korean Medical Science ; : e68-2019.
Article in English | WPRIM | ID: wpr-765172


BACKGROUND: We investigated whether there is a difference in elastographic parameters between pregnancies with and without spontaneous preterm delivery (sPTD) in women with a short cervix (≤ 25 mm), and examined the ability of elastographic parameters to predict sPTD in those women. METHODS: E-CervixTM (WS80A; Samsung Medison, Seoul, Korea) elastography was used to examine the cervical strain. Elastographic parameters were compared between pregnancies with and without sPTD. Diagnostic performance of elastographic parameters to predict sPTD ≤ 37 weeks, both alone and in combination with other parameters, was compared with that of cervical length (CL) using area under receiver operating characteristic curve (AUC) analysis. RESULTS: A total of 130 women were included. Median gestational age (GA) at examination was 24.4 weeks (interquartile range, 21.4–28.9), and the prevalence of sPTD was 20.0% (26/130). Both the elastographic parameters and CL did not show statistical difference between those with and without sPTD. However, when only patients with CL ≥ 1.5 cm (n = 110) were included in the analysis, there was a significant difference between two groups in elasticity contrast index (ECI) within 0.5/1.0/1.5 cm from the cervical canal (P < 0.05) which is one of elastographic parameters generated by E-Cervix. When AUC analysis was performed in women with CL ≥ 1.5 cm, the combination of parameters (CL + pre-pregnancy body mass index + GA at exam + ECI within 0.5/1.0/1.5 cm) showed a significantly higher AUC than CL alone (P < 0.05). CONCLUSION: An addition of cervical elastography may improve the ability to predict sPTD in women with a short CL between 1.5 and 2.5 cm.

Female , Humans , Pregnancy , Area Under Curve , Body Mass Index , Cervix Uteri , Elasticity , Elasticity Imaging Techniques , Gestational Age , Pregnant Women , Prevalence , Prospective Studies , ROC Curve , Seoul , Ultrasonography
Clinical Endoscopy ; : 360-364, 2019.
Article in English | WPRIM | ID: wpr-763452


BACKGROUND/AIMS: Endoscopic ultrasound (EUS) has a limited ability to determine the nature of solid pancreatic lesions (SPLs). Most recent ultrasound processors are provided with elastography software, which allows quantification of the tissue hardness. The aim of this study is to evaluate the effectiveness of the elasticity score (ES) and strain ratio (SR) in the differentiation of benign pancreatic lesions from malignant pancreatic lesions. METHODS: The study had a retrospective design; it included 97 patients with SPLs and 19 patients with inflammatory lesions. The ES and SR were determined during the examination; finally, EUS-guided fine needle aspiration was performed. RESULTS: In this 2-year study, 116 patients were enrolled (97 with malignant lesions and 19 with benign lesions). There were 69 men and 47 women. Their median age was 55.9 years. A cut-off point was detected at SR of 7.75 with a specificity of 99.9%, sensitivity of 90.7%, positive predictive value (PPV) of 99.9%, negative predictive value (NPV) of 67.9%, and accuracy of 92.2%. After adding the ES to the SR, the cut-off point at 7.75 resulted in a specificity of 94.6%, sensitivity of 99%, PPV of 98%, NPV of 98.5%, and accuracy of 97%. CONCLUSIONS: The use of the ES combined with the SR increases the accuracy of differentiation between benign and malignant SPLs and is an effective method for the evaluation of pancreatic masses.

Female , Humans , Male , Biopsy, Fine-Needle , Elasticity , Elasticity Imaging Techniques , Hardness , Methods , Pancreas , Retrospective Studies , Sensitivity and Specificity , Ultrasonography