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1.
Croat Med J ; 61(3): 223-229, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32643338

RESUMO

AIM: To determine the relationship between breast stiffness assessed with sonoelastography (elasticity) and breast tissue density assessed with mammography (MG) and ultrasound (US). METHODS: This cross-sectional study involved 100 women who underwent MG, gray-scale US, and shear-wave sonoelastography during 2013. Mammographic density was categorized into four groups and sonographic density into three groups according to Breast Imaging-Reporting and Data System criteria. The stiffness of breast parenchymal and adipose tissue in all breast quadrants was quantified by shear-wave sonoelastography. Mean elastographic estimates were compared with MG- and US-derived density estimates. RESULTS: Parenchymal and adipose tissue elasticity positively correlated with MG- and US-derived breast density (for parenchyma: for MG Kendall's tau b 0.522; Jonckheere-Terpstra test P<0.001 and for US Kendall's tau b 0.533; Jonckheere-Terpstra test P<0.001); the higher was the breast density on MG and US, the higher was the elastographic stiffness. CONCLUSION: Sonoelastographic breast stiffness strongly positively correlated with breast density. Thus, sonoelastography may have a potential for estimating the breast cancer risk, which allows a novel application of this technique in routine clinical practice.


Assuntos
Tecido Adiposo/fisiologia , Densidade da Mama/fisiologia , Mama/diagnóstico por imagem , Mama/fisiologia , Técnicas de Imagem por Elasticidade/métodos , Tecido Parenquimatoso/fisiologia , Ultrassonografia Mamária/métodos , Adulto , Idoso , Estudos Transversais , Elasticidade/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Ultrassonografia
2.
J Gastroenterol Hepatol ; 35(6): 960-966, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31782974

RESUMO

Performance and advances in liver surgery makes remarkable progress of the understanding of liver regeneration. Liver regeneration after liver resection has been widely researched, and the underlying mechanism mostly concerns proliferation of hepatocytes and the influence by inflammation through activation of Kupffer cells and the other parenchymal cells, the second regenerative pathway by hepatic progenitor cells (HPCs), inducing angiogenesis, remodeling of a extracellular matrix (ECM), and termination mechanisms. New clinical surgeries and the updated multiomics analysis are exploiting the remarkable progress, especially in immune regulation and metabolic process of two emerging hallmarks. This review briefly represents a systemic outline of eight hallmarks, including hepatocyte proliferation, contribution of hepatic progenitor cells, inducing angiogenesis, reprogramming of the extracellular matrix, apoptosis and termination of proliferation, inflammation, immune and metabolic regulation, which are set as organizing characteristics of postoperative liver regeneration and future directions of refining treatment targets.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Regeneração Hepática/fisiologia , Fígado/cirurgia , Proliferação de Células , Matriz Extracelular/metabolismo , Hepatócitos/fisiologia , Humanos , Células de Kupffer/fisiologia , Fígado/citologia , Fígado/metabolismo , Fígado/fisiopatologia , Neovascularização Fisiológica , Tecido Parenquimatoso/citologia , Tecido Parenquimatoso/fisiologia , Período Pós-Operatório , Células-Tronco/fisiologia
3.
Nat Mater ; 18(6): 627-637, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31114073

RESUMO

Cells are transplanted to regenerate an organs' parenchyma, but how transplanted parenchymal cells induce stromal regeneration is elusive. Despite the common use of a decellularized matrix, little is known as to the pivotal signals that must be restored for tissue or organ regeneration. We report that Alx3, a developmentally important gene, orchestrated adult parenchymal and stromal regeneration by directly transactivating Wnt3a and vascular endothelial growth factor. In contrast to the modest parenchyma formed by native adult progenitors, Alx3-restored cells in decellularized scaffolds not only produced vascularized stroma that involved vascular endothelial growth factor signalling, but also parenchymal dentin via the Wnt/ß-catenin pathway. In an orthotopic large-animal model following parenchyma and stroma ablation, Wnt3a-recruited endogenous cells regenerated neurovascular stroma and differentiated into parenchymal odontoblast-like cells that extended the processes into newly formed dentin with a structure-mechanical equivalency to native dentin. Thus, the Alx3-Wnt3a axis enables postnatal progenitors with a modest innate regenerative capacity to regenerate adult tissues. Depleted signals in the decellularized matrix may be reinstated by a developmentally pivotal gene or corresponding protein.


Assuntos
Proteínas de Homeodomínio/metabolismo , Tecido Parenquimatoso/fisiologia , Dente/citologia , Dente/embriologia , Adolescente , Animais , Feminino , Proteínas de Homeodomínio/genética , Humanos , Incisivo/citologia , Incisivo/embriologia , Camundongos Endogâmicos , Dente Serotino/citologia , Técnicas de Cultura de Órgãos , Tecido Parenquimatoso/citologia , Gravidez , Regiões Promotoras Genéticas , Regeneração , Células Estromais/fisiologia , Suínos , Fator A de Crescimento do Endotélio Vascular/genética , Proteína Wnt3A/genética , Proteína Wnt3A/metabolismo
4.
PLoS One ; 12(4): e0174660, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28369092

RESUMO

OBJECTIVES: Accumulation of intrapancreatic fat may be important in type 2 diabetes, but widely varying data have been reported. The standard quantification by MRI in vivo is time consuming and dependent upon a high level of experience. We aimed to develop a new method which would minimise inter-observer variation and to compare this against previously published datasets. METHODS: A technique of 'biopsying' the image to minimise inclusion of non-parenchymal tissues was developed. Additionally, thresholding was applied to exclude both pancreatic ducts and intrusions of visceral fat, with pixels of fat values of <1% or >20% being excluded. The new MR image 'biopsy' (MR-opsy) was compared to the standard method by 6 independent observers with wide experience of image analysis but no experience of pancreas imaging. The effect of the new method was examined on datasets from two studies of weight loss in type 2 diabetes. RESULTS: At low levels of intrapancreatic fat neither the result nor the inter-observer CV was changed by MR-opsy, thresholding or a combination of the methods. However, at higher levels the conventional method exhibited poor inter-observer agreement (coefficient of variation 26.9%) and the new combined method improved the CV to 4.3% (p<0.03). Using either MR-opsy alone or with thresholding, the new methods indicated a closer relationship between decrease in intrapancreatic fat and fall in blood glucose. CONCLUSION: The inter-observer variation for quantifying intrapancreatic fat was substantially improved by the new method when pancreas fat levels were moderately high. The method will improve comparability of pancreas fat measurement between research groups.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Gordura Intra-Abdominal/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Pâncreas/diagnóstico por imagem , Tecido Parenquimatoso/diagnóstico por imagem , Adolescente , Adulto , Idoso , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Gordura Intra-Abdominal/fisiologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Pâncreas/fisiologia , Tecido Parenquimatoso/fisiologia , Reprodutibilidade dos Testes , Adulto Jovem
5.
Environ Health Perspect ; 124(9): 1436-42, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27138294

RESUMO

BACKGROUND: Although occupational exposures contribute to a significant proportion of obstructive lung disease, the phenotype of obstructive lung disease associated with work-related organic dust exposure independent of smoking remains poorly defined. OBJECTIVE: We identified the relative contributions of smoking and occupational endotoxin exposure to parenchymal and airway remodeling as defined by quantitative computed tomography (CT). METHODS: The Shanghai Textile Worker Study is a longitudinal study of endotoxin-exposed cotton workers and endotoxin-unexposed silk workers that was initiated in 1981. Spirometry, occupational endotoxin exposure, and smoking habits were assessed at 5-year intervals. High-resolution computed tomography (CT) was performed in 464 retired workers in 2011, along with quantitative lung densitometric and airway analysis. RESULTS: Significant differences in all CT measures were noted across exposure groups. Occupational endotoxin exposure was associated with a decrease (-1.3%) in percent emphysema (LAAI-950), a 3.3-Hounsfield unit increase in 15th percentile density, an 18.1-g increase in lung mass, and a 2.3% increase in wall area percent. Current but not former smoking was associated with a similar CT phenotype. Changes in LAAI-950 were highly correlated with 15th percentile density (correlation -1.0). Lung mass was the only measure associated with forced expiratory volume in 1 sec (FEV1) decline, with each 10-g increase in lung mass associated with an additional loss (-6.1 mL) of FEV1 (p = 0.001) between 1981 and 2011. CONCLUSIONS: There are many similarities between the effects of occupational endotoxin exposure and those of tobacco smoke exposure on lung parenchyma and airway remodeling. The effects of occupational endotoxin exposure appear to persist even after the cessation of exposure. LAAI-950 may not be a reliable indicator of emphysema in subjects without spirometric impairment. Lung mass is a CT-based biomarker of accelerated lung function decline. CITATION: Lai PS, Hang J, Zhang F, Sun J, Zheng BY, Su L, Washko GR, Christiani DC. 2016. Imaging phenotype of occupational endotoxin-related lung function decline. Environ Health Perspect 124:1436-1442; http://dx.doi.org/10.1289/EHP195.


Assuntos
Remodelação das Vias Aéreas , Endotoxinas/toxicidade , Pneumopatias/diagnóstico por imagem , Pulmão/efeitos dos fármacos , Doenças Profissionais/diagnóstico por imagem , Exposição Ocupacional , Tecido Parenquimatoso/fisiologia , Idoso , Poluentes Ocupacionais do Ar/toxicidade , China , Feminino , Humanos , Estudos Longitudinais , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Tecido Parenquimatoso/diagnóstico por imagem , Testes de Função Respiratória , Fumar/fisiopatologia , Tomografia Computadorizada por Raios X
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