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1.
Dev Biol ; 512: 44-56, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38729406

RESUMO

Impaired formation of the biliary network can lead to congenital cholestatic liver diseases; however, the genes responsible for proper biliary system formation and maintenance have not been fully identified. Combining computational network structure analysis algorithms with a zebrafish forward genetic screen, we identified 24 new zebrafish mutants that display impaired intrahepatic biliary network formation. Complementation tests suggested these 24 mutations affect 24 different genes. We applied unsupervised clustering algorithms to unbiasedly classify the recovered mutants into three classes. Further computational analysis revealed that each of the recovered mutations in these three classes has a unique phenotype on node-subtype composition and distribution within the intrahepatic biliary network. In addition, we found most of the recovered mutations are viable. In those mutant fish, which are already good animal models to study chronic cholestatic liver diseases, the biliary network phenotypes persist into adulthood. Altogether, this study provides unique genetic and computational toolsets that advance our understanding of the molecular pathways leading to biliary system malformation and cholestatic liver diseases.


Assuntos
Sistema Biliar , Mutação , Peixe-Zebra , Peixe-Zebra/genética , Peixe-Zebra/embriologia , Animais , Mutação/genética , Sistema Biliar/embriologia , Sistema Biliar/metabolismo , Fenótipo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
2.
J Biomech Eng ; 146(2)2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37978048

RESUMO

In recent years, transcatheter edge-to-edge repair (TEER) has been widely adopted as an effective treatment for mitral regurgitation (MR). The aim of this study is to develop a personalized in silico model to predict the effect of edge-to-edge repair in advance to the procedure for each individual patient. For this purpose, we propose a combination of a valve deformation model for computing the mitral valve (MV) orifice area (MVOA) and a lumped parameter model for the hemodynamics, specifically mitral regurgitation volume (RVol). Although we cannot obtain detailed information on the three-dimensional flow field near the mitral valve, we can rapidly simulate the important medical parameters for the clinical decision support. In the present method, we construct the patient-specific pre-operative models by using the parameter optimization and then simulate the postoperative state by applying the additional clipping condition. The computed preclip MVOAs show good agreement with the clinical measurements, and the correlation coefficient takes 0.998. In addition, the MR grade in terms of RVol also has good correlation with the grade by ground truth MVOA. Finally, we try to investigate the applicability for the predicting the postclip state. The simulated valve shapes clearly show the well-known double orifice and the improvement of the MVOA, compared with the preclip state. Similarly, we confirmed the improved reverse flow and MR grade in terms of RVol. A total computational time is approximately 8 h by using general-purpose PC. These results obviously indicate that the present in silico model has good capability for the assessment of edge-to-edge repair.


Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Humanos , Insuficiência da Valva Mitral/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Valva Mitral/cirurgia , Resultado do Tratamento , Simulação por Computador
3.
PLoS Genet ; 17(3): e1009402, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33739979

RESUMO

Impaired formation of the intrahepatic biliary network leads to cholestatic liver diseases, which are frequently associated with autoimmune disorders. Using a chemical mutagenesis strategy in zebrafish combined with computational network analysis, we screened for novel genes involved in intrahepatic biliary network formation. We positionally cloned a mutation in the nckap1l gene, which encodes a cytoplasmic adaptor protein for the WAVE regulatory complex. The mutation is located in the last exon after the stop codon of the primary splice isoform, only disrupting a previously unannotated minor splice isoform, which indicates that the minor splice isoform is responsible for the intrahepatic biliary network phenotype. CRISPR/Cas9-mediated nckap1l deletion, which disrupts both the primary and minor isoforms, showed the same defects. In the liver of nckap1l mutant larvae, WAVE regulatory complex component proteins are degraded specifically in biliary epithelial cells, which line the intrahepatic biliary network, thus disrupting the actin organization of these cells. We further show that nckap1l genetically interacts with the Cdk5 pathway in biliary epithelial cells. These data together indicate that although nckap1l was previously considered to be a hematopoietic cell lineage-specific protein, its minor splice isoform acts in biliary epithelial cells to regulate intrahepatic biliary network formation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Processamento Alternativo , Ductos Biliares Intra-Hepáticos/embriologia , Ductos Biliares Intra-Hepáticos/metabolismo , Morfogênese/genética , Alelos , Animais , Animais Geneticamente Modificados , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Ordem dos Genes , Testes Genéticos , Variação Genética , Fígado/metabolismo , Modelos Biológicos , Mutação , Fenótipo , Isoformas de RNA , Peixe-Zebra , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo
4.
Development ; 144(14): 2595-2605, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28720653

RESUMO

The intrahepatic biliary network is a highly branched three-dimensional network lined by biliary epithelial cells, but how its branching patterns are precisely established is not clear. We designed a new computer-based algorithm that quantitatively computes the structural differences of the three-dimensional networks. Utilizing the algorithm, we showed that inhibition of Cyclin-dependent kinase 5 (Cdk5) led to reduced branching in the intrahepatic biliary network in zebrafish. Further, we identified a previously unappreciated downstream kinase cascade regulated by Cdk5. Pharmacological manipulations of this downstream kinase cascade produced a crowded branching defect in the intrahepatic biliary network and influenced actin dynamics in biliary epithelial cells. We generated larvae carrying a mutation in cdk5 regulatory subunit 1a (cdk5r1a), an essential activator of Cdk5. cdk5r1a mutant larvae show similar branching defects as those observed in Cdk5 inhibitor-treated larvae. A small-molecule compound that interferes with the downstream kinase cascade rescued the mutant phenotype. These results provide new insights into branching morphogenesis of the intrahepatic biliary network.


Assuntos
Ductos Biliares Intra-Hepáticos/enzimologia , Ductos Biliares Intra-Hepáticos/crescimento & desenvolvimento , Quinase 5 Dependente de Ciclina/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo , Fatores de Despolimerização de Actina/metabolismo , Algoritmos , Animais , Animais Geneticamente Modificados , Simulação por Computador , Quinase 5 Dependente de Ciclina/antagonistas & inibidores , Quinase 5 Dependente de Ciclina/genética , Técnicas de Inativação de Genes , Imageamento Tridimensional , Larva/crescimento & desenvolvimento , Larva/metabolismo , Quinases Lim/metabolismo , Modelos Anatômicos , Morfogênese/efeitos dos fármacos , Morfogênese/genética , Morfogênese/fisiologia , Mutação , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/antagonistas & inibidores , Proteínas de Peixe-Zebra/genética , Quinases Ativadas por p21/metabolismo
5.
Hepatology ; 70(6): 2107-2122, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31016744

RESUMO

The growing burden of liver fibrosis and lack of effective antifibrotic therapies highlight the need for identification of pathways and complementary model systems of hepatic fibrosis. A rare, monogenic disorder in which children with mutations in mannose phosphate isomerase (MPI) develop liver fibrosis led us to explore the function of MPI and mannose metabolism in liver development and adult liver diseases. Herein, analyses of transcriptomic data from three human liver cohorts demonstrate that MPI gene expression is down-regulated proportionate to fibrosis in chronic liver diseases, including nonalcoholic fatty liver disease and hepatitis B virus. Depletion of MPI in zebrafish liver in vivo and in human hepatic stellate cell (HSC) lines in culture activates fibrotic responses, indicating that loss of MPI promotes HSC activation. We further demonstrate that mannose supplementation can attenuate HSC activation, leading to reduced fibrogenic activation in zebrafish, culture-activated HSCs, and in ethanol-activated HSCs. Conclusion: These data indicate the prospect that modulation of mannose metabolism pathways could reduce HSC activation and improve hepatic fibrosis.


Assuntos
Células Estreladas do Fígado/fisiologia , Cirrose Hepática/etiologia , Manose-6-Fosfato Isomerase/fisiologia , Manose/farmacologia , Animais , Células Cultivadas , Glicosilação , Humanos , Masculino , Fator de Crescimento Derivado de Plaquetas/fisiologia , Transdução de Sinais/fisiologia , Peixe-Zebra
6.
Proc Natl Acad Sci U S A ; 113(11): E1460-9, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26929344

RESUMO

Mitochondria are the site of iron utilization, wherein imported iron is incorporated into heme or iron-sulfur clusters. Previously, we showed that a cytosolic siderophore, which resembles a bacterial siderophore, facilitates mitochondrial iron import in eukaryotes, including zebrafish. An evolutionarily conserved 3-hydroxy butyrate dehydrogenase, 3-hydroxy butyrate dehydrogenase 2 (Bdh2), catalyzes a rate-limiting step in the biogenesis of the eukaryotic siderophore. We found that inactivation of bdh2 in developing zebrafish embryo results in heme deficiency and delays erythroid maturation. The basis for this erythroid maturation defect is not known. Here we show that bdh2 inactivation results in mitochondrial dysfunction and triggers their degradation by mitophagy. Thus, mitochondria are prematurely lost in bdh2-inactivated erythrocytes. Interestingly, bdh2-inactivated erythroid cells also exhibit genomic alterations as indicated by transcriptome analysis. Reestablishment of bdh2 restores mitochondrial function, prevents premature mitochondrial degradation, promotes erythroid development, and reverses altered gene expression. Thus, mitochondrial communication with the nucleus is critical for erythroid development.


Assuntos
Eritrócitos/citologia , Hidroxibutirato Desidrogenase/metabolismo , Mitofagia/fisiologia , Proteínas de Peixe-Zebra/metabolismo , Animais , Autofagia/fisiologia , Embrião não Mamífero/citologia , Eritrócitos/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Inativação Gênica , Hidroxibutirato Desidrogenase/genética , Mitocôndrias/fisiologia , Mitocôndrias/ultraestrutura , Oxigênio/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
7.
Acta Radiol ; 58(5): 600-608, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27522095

RESUMO

Background Increased interest in radiation dose reduction in neurointerventional procedures has led to the development of a method called "spot fluoroscopy" (SF), which enables the operator to collimate a rectangular or square region of interest anywhere within the general field of view. This has potential advantages over conventional collimation, which is limited to symmetric collimation centered over the field of view. Purpose To evaluate the effect of SF on the radiation dose. Material and Methods Thirty-five patients with intracranial aneurysms were treated with endovascular coiling. SF was used in 16 patients and conventional fluoroscopy in 19. The following parameters were analyzed: the total fluoroscopic time, the total air kerma, the total fluoroscopic dose-area product, and the fluoroscopic dose-area product rate. Statistical differences were determined using the Welch's t-test. Results The use of SF led to a reduction of 50% of the total fluoroscopic dose-area product (CF = 106.21 Gycm2, SD = 99.06 Gycm2 versus SF = 51.80 Gycm2, SD = 21.03 Gycm2, p = 0.003884) and significant reduction of the total fluoroscopic dose-area product rate (CF = 1.42 Gycm2/min, SD = 0.57 Gycm2/s versus SF = 0.83 Gycm2/min, SD = 0.37 Gycm2/min, p = 0.00106). The use of SF did not lead to an increase in fluoroscopy time or an increase in total fluoroscopic cumulative air kerma, regardless of collimation. Conclusion The SF function is a new and promising tool for reduction of the radiation dose during neurointerventional procedures.


Assuntos
Aneurisma Intracraniano/diagnóstico por imagem , Doses de Radiação , Lesões por Radiação/prevenção & controle , Radiografia Intervencionista/métodos , Encéfalo/diagnóstico por imagem , Feminino , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
8.
Hepatology ; 58(4): 1326-38, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23744565

RESUMO

UNLABELLED: Nonalcoholic fatty liver disease is the most common liver disease in both adults and children. The earliest stage of this disease is hepatic steatosis, in which triglycerides are deposited as cytoplasmic lipid droplets in hepatocytes. Through a forward genetic approach in zebrafish, we found that guanosine monophosphate (GMP) synthetase mutant larvae develop hepatic steatosis. We further demonstrate that activity of the small GTPase Rac1 and Rac1-mediated production of reactive oxygen species (ROS) are down-regulated in GMP synthetase mutant larvae. Inhibition of Rac1 activity or ROS production in wild-type larvae by small molecule inhibitors was sufficient to induce hepatic steatosis. More conclusively, treating larvae with hydrogen peroxide, a diffusible ROS that has been implicated as a signaling molecule, alleviated hepatic steatosis in both GMP synthetase mutant and Rac1 inhibitor-treated larvae, indicating that homeostatic production of ROS is required to prevent hepatic steatosis. We further found that ROS positively regulate the expression of the triglyceride hydrolase gene, which is responsible for the mobilization of stored triglycerides in hepatocytes. Consistently, inhibition of triglyceride hydrolase activity in wild-type larvae by a small molecule inhibitor was sufficient to induce hepatic steatosis. CONCLUSION: De novo GMP synthesis influences the activation of the small GTPase Rac1, which controls hepatic lipid dynamics through ROS-mediated regulation of triglyceride hydrolase expression in hepatocytes.


Assuntos
Fígado Gorduroso/prevenção & controle , Homeostase/fisiologia , Fígado/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra/metabolismo , Animais , Carbono-Nitrogênio Ligases/genética , Carbono-Nitrogênio Ligases/metabolismo , Modelos Animais de Doenças , Fígado Gorduroso/metabolismo , Modelos Animais , Mutação/genética , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
9.
Phys Med Biol ; 69(3)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38100829

RESUMO

Objective. Accurate extraction of mitral valve shape from clinical tomographic images acquired in patients has proven useful for planning surgical and interventional mitral valve treatments. However, manual extraction of the mitral valve shape is laborious, and the existing automatic extraction methods have not been sufficiently accurate. In this paper, we propose a fully automated method of extracting mitral valve shape from computed tomography (CT) images for the all phases of the cardiac cycle.Approach. This method extracts the mitral valve shape based on DenseNet using both the original CT image and the existence probability maps of the mitral valve area inferred by U-Net as input. A total of 1585 CT images from 204 patients with various cardiac diseases including mitral regurgitation were collected and manually annotated for mitral valve region. The proposed method was trained and evaluated by 10-fold cross validation using the collected data and was compared with the method without the existence probability maps.Main results. The mean error of shape extraction error in the proposed method is 0.88 mm, which is an improvement of 0.32 mm compared with the method without the existence probability maps.Significance. We present a novel fully automatic mitral valve extraction method from input to output for all phases of 4D CT images. We suggest that the accuracy of mitral valve shape extraction is improved by using existence probability maps.


Assuntos
Valva Mitral , Tomografia Computadorizada por Raios X , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Tomografia Computadorizada por Raios X/métodos
10.
Dev Biol ; 363(1): 128-37, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22222761

RESUMO

Biliary epithelial cells line the intrahepatic biliary network, a complex three-dimensional network of conduits. The loss of differentiated biliary epithelial cells is the primary cause of many congenital liver diseases. We identified a zebrafish snapc4 (small nuclear RNA-activating complex polypeptide 4) mutant in which biliary epithelial cells initially differentiate but subsequently disappear. In these snapc4 mutant larvae, biliary epithelial cells undergo apoptosis, leading to degeneration of the intrahepatic biliary network. Consequently, in snapc4 mutant larvae, biliary transport of ingested fluorescent lipids to the gallbladder is blocked. Snapc4 is the largest subunit of a protein complex that regulates small nuclear RNA (snRNA) transcription. The snapc4(s445) mutation causes a truncation of the C-terminus, thereby deleting the domain responsible for a specific interaction with Snapc2, a vertebrate specific subunit of the SNAP complex. This mutation leads to a hypomorphic phenotype, as only a subset of snRNA transcripts are quantitatively altered in snapc4(s445) mutant larvae. snapc2 knockdown also disrupts the intrahepatic biliary network in a similar fashion as in snapc4(s445) mutant larvae. These data indicate that the physical interaction between Snapc2 and Snapc4 is important for the expression of a subset of snRNAs and biliary epithelial cell survival in zebrafish.


Assuntos
Fígado/metabolismo , Mutação , Fatores de Transcrição/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Sítios de Ligação/genética , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Redes Reguladoras de Genes , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Fígado/citologia , Fígado/crescimento & desenvolvimento , Masculino , Microscopia Confocal , Microscopia Eletrônica , Ligação Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Fatores de Transcrição/metabolismo , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
11.
Cancer Cell ; 41(8): 1480-1497.e9, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37451272

RESUMO

Radiation therapy (RT) provides therapeutic benefits for patients with glioblastoma (GBM), but inevitably induces poorly understood global changes in GBM and its microenvironment (TME) that promote radio-resistance and recurrence. Through a cell surface marker screen, we identified that CD142 (tissue factor or F3) is robustly induced in the senescence-associated ß-galactosidase (SA-ßGal)-positive GBM cells after irradiation. F3 promotes clonal expansion of irradiated SA-ßGal+ GBM cells and orchestrates oncogenic TME remodeling by activating both tumor-autonomous signaling and extrinsic coagulation pathways. Intratumoral F3 signaling induces a mesenchymal-like cell state transition and elevated chemokine secretion. Simultaneously, F3-mediated focal hypercoagulation states lead to activation of tumor-associated macrophages (TAMs) and extracellular matrix (ECM) remodeling. A newly developed F3-targeting agent potently inhibits the aforementioned oncogenic events and impedes tumor relapse in vivo. These findings support F3 as a critical regulator for therapeutic resistance and oncogenic senescence in GBM, opening potential therapeutic avenues.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/radioterapia , Tromboplastina , Linhagem Celular Tumoral , Recidiva Local de Neoplasia , Transdução de Sinais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/metabolismo , Microambiente Tumoral
12.
Acta Cytol ; 56(2): 166-70, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22378079

RESUMO

OBJECTIVE: It was the aim of this study to evaluate the diagnostic utility of Notch-1 immunocytochemistry in distinguishing endometrial glandular and stromal breakdown (EGBD) from endometrial adenocarcinoma in endometrial cytology. STUDY DESIGN: Samples of normal endometrium, EGBD and endometrial adenocarcinoma were subjected to immunocytochemical staining for Notch-1, and we examined the labeling index (LI) of Notch-1 (the ratio of intranuclear Notch-1-positive cells to total cells). We compared (1) the Notch-1 LI in normal endometrium, (2) the Notch-1 LI between normal endometrium and endometrial adenocarcinoma, and (3) the Notch-1 LI in normal endometrium, EGBD and endometrial adenocarcinoma. RESULTS: In analysis item 1, the LI of Notch-1 was 32.9 ± 8.4, 19.4 ± 8.2 and 12.5 ± 7.5% in proliferative endometrium, secretory endometrium and atrophic endometrium, respectively. In analysis item 2, the LI of Notch-1 in endometrial adenocarcinoma was 45.2 ± 7.4%, which was significantly higher than that in normal endometrium. In analysis item 3, the LI of Notch-1 in EGBD was 31.3 ± 8.3%, which was significantly lower than that in endometrial adenocarcinoma. CONCLUSION: In conclusion, Notch-1 immunocytochemistry is a useful method for distinguishing between EGBD and endometrial carcinoma in endometrial cytology.


Assuntos
Adenocarcinoma/diagnóstico , Neoplasias do Endométrio/diagnóstico , Receptor Notch1/análise , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Biomarcadores Tumorais/análise , Biópsia/métodos , Contagem de Células , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Endométrio/citologia , Endométrio/metabolismo , Endométrio/patologia , Feminino , Humanos , Imuno-Histoquímica/métodos , Pessoa de Meia-Idade , Células Estromais/citologia , Células Estromais/metabolismo , Células Estromais/patologia
13.
Sci Rep ; 12(1): 14264, 2022 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-35995924

RESUMO

Quantitative assessment of the right-to-left ratio of pulmonary blood flow distribution is important for determining the clinical indications for treating pulmonary arterial branch stenosis. A novel theory was recently proposed that can be used to quantitatively assess the right-to-left ratio on conventional X-ray angiography images. In the proposal, further developments were indicated, especially automated calculation. In this study, a new automated algorithm was developed. In the X-ray image, regions of interest were set in right and left lung, and time-signal intensity curves were measured. The new automated algorithm is applied to determine the optimal time window for the analysis of the time-signal intensity curve and to calculate the slope of the curve in the optimized time window. The right-to-left ratios in seven consecutive patients calculated by the new automated algorithm were compared to those calculated by lung perfusion scintigraphy. The ratios were in good agreement with linear regression with a slope of 1.27 and a Pearson correlation coefficient of 0.95. The processing time was less than 10 s, which is one-eighth of the manual processing time. The new automated algorithm is accurate, stable, and fast enough for clinical use in the real world.


Assuntos
Pneumopatias , Circulação Pulmonar , Algoritmos , Angiografia , Humanos , Pulmão/diagnóstico por imagem , Raios X
14.
Int J Comput Assist Radiol Surg ; 17(11): 2041-2049, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35930131

RESUMO

PURPOSE: Detection of early-stage liver fibrosis has direct clinical implications on patient management and treatment. The aim of this paper is to develop a non-invasive, cost-effective method for classifying liver disease between "non-fibrosis" (F0) and "fibrosis" (F1-F4), and to evaluate the classification performance quantitatively. METHODS: Image data from 75 patients who underwent a simultaneous liver biopsy and non-contrast CT examination were used for this study. Non-contrast CT image texture features such as wavelet-based features, standard deviation of variance filter, and mean CT number were calculated in volumes of interest (VOIs) positioned within the liver parenchyma. In addition, a combined feature was calculated using logistic regression with L2-norm regularization to further improve fibrosis detection. Based on the final pathology from the liver biopsy, the patients were labelled either as "non-fibrosis" or "fibrosis". Receiver-operating characteristic (ROC) curve, area under the ROC curve (AUROC), specificity, sensitivity, and accuracy were determined for the algorithm to differentiate between "non-fibrosis" and "fibrosis". RESULTS: The combined feature showed the highest classification performance with an AUROC of 0.86, compared to the wavelet-based feature (AUROC, 0.76), the standard deviation of variance filter (AUROC, 0.65), and mean CT number (AUROC, 0.84). The combined feature's specificity, sensitivity, and accuracy were 0.66, 0.88, and 0.76, respectively, showing the most promising results. CONCLUSION: A new non-invasive and cost-effective method was developed to classify liver diseases between "non-fibrosis" (F0) and "fibrosis" (F1-F4). The proposed method makes it possible to detect liver fibrosis in asymptomatic patients using non-contrast CT images for better patient management and treatment.


Assuntos
Cirrose Hepática , Fígado , Algoritmos , Biópsia , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Curva ROC , Tomografia Computadorizada por Raios X/métodos
15.
J Imaging ; 8(1)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35049852

RESUMO

Accurate morphological information on aortic valve cusps is critical in treatment planning. Image segmentation is necessary to acquire this information, but manual segmentation is tedious and time consuming. In this paper, we propose a fully automatic aortic valve cusps segmentation method from CT images by combining two deep neural networks, spatial configuration-Net for detecting anatomical landmarks and U-Net for segmentation of aortic valve components. A total of 258 CT volumes of end systolic and end diastolic phases, which include cases with and without severe calcifications, were collected and manually annotated for each aortic valve component. The collected CT volumes were split 6:2:2 for the training, validation and test steps, and our method was evaluated by five-fold cross validation. The segmentation was successful for all CT volumes with 69.26 s as mean processing time. For the segmentation results of the aortic root, the right-coronary cusp, the left-coronary cusp and the non-coronary cusp, mean Dice Coefficient were 0.95, 0.70, 0.69, and 0.67, respectively. There were strong correlations between measurement values automatically calculated based on the annotations and those based on the segmentation results. The results suggest that our method can be used to automatically obtain measurement values for aortic valve morphology.

16.
Curr Biol ; 18(20): 1565-71, 2008 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-18951027

RESUMO

Emerging evidence indicates that paracrine signals from endothelial cells play a role in tissue differentiation and organ formation [1-3]. Here, we identify a novel role for endothelial cells in modulating hepatocyte polarization during liver organogenesis. We find that in zebrafish, the apical domain of the hepatocytes predicts the location of the intrahepatic biliary network. The refinement of hepatocyte polarization coincides with the invasion of endothelial cells into the liver, and these endothelial cells migrate along the maturing basal surface of the hepatocytes. Using genetic, pharmacological, and transplantation experiments, we provide evidence that endothelial cells influence the polarization of the adjacent hepatocytes. This influence of endothelial cells on hepatocytes is mediated at least in part by the cell-surface protein Heart of glass and contributes to the establishment of coordinately aligned hepatocyte apical membranes and evenly spaced intrahepatic conduits.


Assuntos
Polaridade Celular , Células Endoteliais/metabolismo , Hepatócitos/metabolismo , Fígado/embriologia , Peixe-Zebra/embriologia , Molécula de Adesão de Leucócito Ativado/metabolismo , Animais , Membrana Celular/metabolismo , Movimento Celular , Regulação da Expressão Gênica no Desenvolvimento , Fígado/citologia , Glicoproteínas de Membrana/metabolismo , Organogênese , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
17.
PLoS One ; 16(6): e0253565, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34185820

RESUMO

OBJECTIVE: Quantitative assessment of pulmonary blood flow distribution is important when determining the clinical indications for treating pulmonary arterial branch stenosis. Lung perfusion scintigraphy is currently the gold standard for quantitative blood flow measurement. However, it is expensive, cannot provide a real-time assessment, requires additional sedation, and exposes the patient to ionizing radiation. The aim of this study was to investigate the feasibility of a novel technology for measuring pulmonary blood flow distribution in each lung by conventional X-ray pulmonary angiography and to compare its performance to that of lung perfusion scintigraphy. METHODS: Contrast-enhanced X-ray pulmonary angiography images were acquired at a frame rate of 30 frames per second. The baseline mask image, obtained before contrast agent injection, was subtracted from subsequent, consecutive images. The time-signal intensity curves of two regions of interest, established at each lung field, were obtained on a frame-to-frame basis. The net increase in signal intensity within each region at the torrent period during the second cardiac cycle before contrast agent enhancement over the total lung field was measured, and the right-to-left ratio of the signal intensity was calculated. The right-to-left ratio obtained with this approach was compared to that obtained with scintigraphy. Agreement of the right-to-left ratio between X-ray angiography and lung scintigraphy measurements was assessed using linear fitting with the Pearson correlation coefficient. RESULT: The calculation of the right-to-left ratio of pulmonary blood flow by our kinetic model was feasible for seven children as a pilot study. The right-to-left ratio of pulmonary blood flow distribution calculated from pulmonary angiography was in good agreement with that of lung perfusion scintigraphy, with a Pearson correlation coefficient of 0.91 and a slope of linear fit of 1.2 (p<0.005). CONCLUSION: The novel diagnostic technology using X-ray pulmonary angiography from our kinetic model can feasibly quantify the right-to-left ratio of pulmonary blood flow distribution. This technology may serve as a substitute for lung perfusion scintigraphy, which is quite beneficial for small children susceptible to radiation exposure.


Assuntos
Angiografia por Tomografia Computadorizada , Pulmão , Modelos Cardiovasculares , Circulação Pulmonar , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Pulmão/irrigação sanguínea , Pulmão/diagnóstico por imagem , Masculino , Projetos Piloto , Cintilografia
18.
J Cardiovasc Comput Tomogr ; 14(4): 356-362, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31787591

RESUMO

BACKGROUND: Onsite workstation-based CT-derived Fractional-Flow-Reserve (CT-FFR) is accurate in assessing hemodynamic-significance of coronary stenoses. We aim to describe the influence of operator expertise and luminal-segmentation technique on the diagnostic performance, precision and reproducibility of CT-FFR in identifying hemodynamically-significant stenosis (FFR≤0.8). METHODS: Forty-eight consecutive stable-patients (86 vessels) with suspected CAD underwent research indicated invasive-FFR and 320-detector CT-coronary-angiography (CTA). CT-FFR was derived using reduced-order model on standard desktop-computer. Semi-automated coronary luminal segmentation was performed using focused-technique with manual adjustments at regions of stenosis and calcification or comprehensive-technique with manual adjustments along the entire course of the vessel. CT-FFR analysis was performed using 3 blinded operators; core-laboratory engineer using focused-technique and radiographer and cardiologist using the comprehensive-technique. Diagnostic performance was assessed by area under receiver-operating-curve (AUC). Precision with invasive FFR was determined by Bland-Altman analysis, and reproducibility by intraclass-correlation-coefficient (ICC). RESULTS: Diagnostic performance was comparable among operators (Engineer: AUC = 0.88, Radiographer 0.84; Cardiologist 0.87; P = 0.59). Coronary luminal-segmentation time was shortest using focused technique (engineer 6:17 ± 2.43 min), compared with comprehensive technique (cardiologist 14.83 ± 7.09, radiographer 24.74 ± 12.65; P < 0.001). Use of focused technique was associated with widest limits of agreement (LOA) with FFR and moderate intra-operator reproducibility (engineer LOA -0.20-0.33; ICC 0.66), when compared with the comprehensive technique which demonstrated narrower LOA and excellent reproducibility [radiographer (LOA -0.17-0.20, ICC = 0.91) and cardiologist (LOA-0.15-0.23, ICC = -0.93)] CONCLUSION: A workstation-based CT-FFR technique was reproducible with high and comparable diagnostic performance among operators with different expertise. A comprehensive luminal segmentation technique was the most time-consuming and associated with the highest reproducibility and precision with FFR.


Assuntos
Cardiologistas , Competência Clínica , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico , Tomografia Computadorizada Multidetectores , Interpretação de Imagem Radiográfica Assistida por Computador , Radiologistas , Idoso , Doença da Artéria Coronariana/fisiopatologia , Estenose Coronária/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
19.
Ann Diagn Pathol ; 13(2): 89-95, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19302956

RESUMO

Various metaplastic changes may be present in endometrium, in which also cellular atypias may often be observed. Particularly, eosinophilic and ciliated changes (ECCs) occur in both nonneoplastic and neoplastic endometrium. This may cause confusion in the cytodiagnosis. This study was enterprised to investigate the possible help of immunocytochemical and cytogenetic study in the diagnostic and biologic assessment of ECC cells. In immunocytochemistry for p53 protein, Ki-67, and cyclin A, the material consists of 40 cases of cytologic smears examined by direct sampling of the endometrial cavity comprising 30 cases of ECC in endometrial glandular and stromal breakdown (EGBD) and 10 cases of well-differentiated adenocarcinoma (G1). After cytodiagnosis, immunostaining for p53 protein, Ki-67, and cyclin A was performed on multiple wet-fixed slides from each single case to evaluate the immunoreactivity, intensity of nuclear staining, and nuclear labeling index (N-LI). The intensity of nuclear staining was scored as negative (0), weak (1), moderate (2), or strong (3), and the N-LI was scored as less than 10% (0), from 10% to 25% (1), from 26% to 50% (2), or more than 50% (3), and the final score was calculated by adding both partial scores. A statistical significance test was performed by using Mann-Whitney U test, and the result was judged as significant when the P value was less than .05. For genetic mutation analysis of p53, the material comprised 6 cases of EGBD in which a high score was measured with immunocytochemistry for p53 protein, and the presence of ECC was confirmed on the hematoxylin and eosin. The ECC cells on paraffin-embedded specimens were captured using laser capture microdissection technology. Mutations in p53 gene (exons 5-8) were examined using DNA sequencing analysis. In immunocytochemistry for p53 protein, Ki-67, and cyclin A, the proportions of immunoreactive cells for p53 were statistically higher in ECC compared with those of G1 (P < .05). The proportions of the immunoreactive cells for Ki-67 and cyclin A were statistically higher in G1 compared with those of ECC (P < .05). (2) In genetic mutation analysis of p53, DNA sequencing of p53 in 6 cases revealed no mutations. The percentage of immunoreactive cells for p53 protein were higher in ECC than in G1, but the mutation point was not confirmed in genetic mutation analysis. The differential expression of these biologic parameters in ECC cells could be considered of possible relevance to the cytopathologic diagnosis in the future.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/patologia , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Endométrio/patologia , Adenocarcinoma/metabolismo , Sequência de Bases , Cílios/patologia , Ciclina A/biossíntese , Neoplasias do Endométrio/metabolismo , Endométrio/metabolismo , Amarelo de Eosina-(YS) , Feminino , Humanos , Imuno-Histoquímica , Antígeno Ki-67/biossíntese , Lasers , Metaplasia , Microdissecção , Dados de Sequência Molecular , Mutação , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética
20.
Eur Heart J Cardiovasc Imaging ; 19(11): 1234-1243, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30137268

RESUMO

Aims: To compare the diagnostic performance of a reduced-order computed tomography-derived fractional flow reserve (CT-FFR) technique derived from luminal deformation and static CT stress myocardial perfusion (CTP). Methods and results: Forty-six patients (84 vessels) with suspected coronary artery disease from a single institution planned for elective coronary angiography prospectively underwent research indicated invasive fractional flow reserve (FFR) and 320-detector CT coronary angiography (CTA) and static CTP. Analyses were performed in separate blinded core laboratories for CT-FFR and CTP. CT-FFR was derived using a reduced-order model with dedicated software on a standard desktop computer. CTP was assessed visually and quantitatively by transmural perfusion ratio (TPR). Invasive FFR was significant in 33% (28/84) of vessels. Overall per-vessel sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for CT-FFR were 81%, 84%, 71%, 90%, and 83%, respectively, those of visual CTP were 54%, 92%, 79%, 77%, and 78%, respectively, and TPR were 64%, 48%, 42%, 70%, and 54%, respectively. Per-vessel receiver operator curve analysis demonstrated a significantly larger area under the curve (AUC) for CT-FFR (0.89) with that for visual CTP (0.72; P = 0.016), TPR (0.55; P < 0.0001), and CTA (0.76; P = 0.04). The addition of CT-FFR to CTA provided superior improvement in performance (AUC 0.93; P < 0.0001) compared with CTA alone, a combination of CTA with visual CTP (AUC 0.82; P = 0.007) and CTA with TPR (AUC 0.78; P = 0.0006). Conclusion: Based on this selected cohort of patients, a reduced-order CT-FFR technique is superior to visual and quantitatively assessed static CTP in detecting haemodynamically significant coronary stenosis as assessed by invasive FFR.


Assuntos
Angiografia por Tomografia Computadorizada , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/fisiopatologia , Reserva Fracionada de Fluxo Miocárdico , Imagem de Perfusão do Miocárdio/métodos , Idoso , Simulação por Computador , Angiografia Coronária , Estenose Coronária/diagnóstico , Teste de Esforço , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares
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