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1.
J Magn Reson Imaging ; 59(3): 1034-1042, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37272790

RESUMO

BACKGROUND: The assessment of resectability after neoadjuvant chemotherapy of hepatoblastoma is dependent on Post-Treatment EXTENT of Disease (POSTTEXT) staging and its annotation factors P (portal venous involvement) and V (hepatic venous/inferior vena cava [IVC] involvement), but MR performance in assessing them remains unclear. PURPOSE: To assess the diagnostic performance of contrast-enhanced MR imaging for preoperative POSTTEXT staging and diagnosing vascular involvement in terms of annotation factors P and V in pediatric hepatoblastoma following neoadjuvant chemotherapy. STUDY TYPE: Retrospective. SUBJECTS: Thirty-five consecutive patients (17 males, median age, 24 months; age range, 6-98 months) with proven hepatoblastoma underwent preoperative MR imaging following neoadjuvant chemotherapy. FIELD STRENGTH/SEQUENCE: 3.0 T; T2-weighted imaging (T2WI), T2WI with fat suppression, diffusion weighted imaging, radial stack-of-the-star/Cartesian 3D Dixon T1-weighted gradient echo imaging. ASSESSMENT: Three radiologists independently assessed the POSTTEXT stages and annotation factors P and V based on the 2017 PRE/POSTTEXT system. The sensitivities and specificities were calculated for 1) diagnosing each POSTTEXT stage; 2) discrimination of stages III and IV (advanced) from those stages I and II (non-advanced) hepatoblastomas; and 3) annotation factors P and V. The combination of pathologic findings and surgical records served as the reference standard. STATISTICAL TESTS: Sensitivity, specificity, Fleiss kappa test. RESULTS: The sensitivity and specificity ranges for discriminating advanced from non-advanced hepatoblastomas were 73.3%-80.0% and 80.0%-90.0%, respectively. For annotation factor P, they were 66.7%-100.0% and 90.6%, respectively. For factor V, they were 75.0% and 67.7%-83.9%, respectively. There was excellent, substantial, and moderate agreement on POSTTEXT staging (Fleiss kappa = 0.82), factors P (Fleiss kappa = 0.64), and factors V (Fleiss kappa = 0.60), respectively. DATA CONCLUSION: MR POSTTEXT provides reliable discrimination between advanced and non-advanced tumors, and MR has moderate to excellent specificity at identifying portal venous and hepatic venous/IVC involvement. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.


Assuntos
Hepatoblastoma , Neoplasias Hepáticas , Masculino , Criança , Humanos , Pré-Escolar , Lactente , Hepatoblastoma/tratamento farmacológico , Hepatoblastoma/patologia , Hepatoblastoma/cirurgia , Terapia Neoadjuvante , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Veias Hepáticas , Sensibilidade e Especificidade , Neoplasias Hepáticas/patologia , Estadiamento de Neoplasias
2.
World J Surg Oncol ; 21(1): 239, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37542314

RESUMO

BACKGROUND: As digital medicine has exerted profound influences upon diagnosis and treatment of hepatobiliary diseases, our study aims to investigate the accuracy of three-dimensional visualization and evaluation (3DVE) system in assessing the resectability of hilar cholangiocarcinoma (hCCA), and explores its potential clinical value. MATERIALS AND METHODS: The discovery cohort, containing 111 patients from April 2013 to December 2019, was retrospectively included to determine resectability according to revised criteria for unresectability of hCCA. 3D visualization models were reconstructed to evaluate resectability parameters including biliary infiltration, vascular involvement, hepatic atrophy and metastasis. Evaluation accuracy were compared between contrast-enhanced CT and 3DVE. Logistic analysis was performed to identify independent risk factors of R0 resection. A new comprehensive 3DVE classification of hCCA based on factors influencing resectability was proposed to investigate its role in predicting R0 resection and prognosis. The main outcomes were also analyzed in cohort validation, including 34 patients from January 2020 to August 2022. RESULTS: 3DVE showed an accuracy rate of 91% (95%CI 83.6-95.4%) in preoperatively evaluating hCCA resectability, significantly higher than 81% (95%CI 72.8-87.7%) of that of CT (p = 0.03). By multivariable analysis, hepatic artery involvement in 3DVE was identified an independent risk factor for R1 or R2 resection (OR = 3.5, 95%CI 1.4,8.8, P < 0.01). New 3DVE hCCA classification was valuable in predicting patients' R0 resection rate (p < 0.001) and prognosis (p < 0.0001). The main outcomes were internally validated. CONCLUSIONS: 3DVE exhibited a better efficacy in evaluating hCCA resectability, compared with contrast-enhanced CT. Preoperative 3DVE demonstrated hepatic artery involvement was an independent risk factor for the absence of R0 margin. 3DVE classification of hCCA was valuable in clinical practice.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Humanos , Tumor de Klatskin/diagnóstico por imagem , Tumor de Klatskin/cirurgia , Tumor de Klatskin/patologia , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Colangiocarcinoma/patologia , Imageamento Tridimensional , Estudos Retrospectivos , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/cirurgia , Ductos Biliares Intra-Hepáticos/patologia
3.
Hepatobiliary Pancreat Dis Int ; 15(4): 391-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27498579

RESUMO

BACKGROUND: Pyogenic hepatic abscess may mimic primary or secondary carcinoma of the liver on contrast-enhanced computed tomography (CECT). The present study was to explore the usefulness of the analysis of multislice-based texture acquired from CECT in the differentiation between pyogenic hepatic abscesses and malignant mimickers. METHODS: This retrospective study included 25 abscesses in 20 patients and 33 tumors in 26 subjects who underwent CECT. To make comparison, we also enrolled 19 patients with hepatic single simple cyst. The images from CECT were analyzed using a Laplacian of Gaussian band-pass filter (5 filter levels with sigma weighting ranging from 1.0 to 2.5). We also quantified the uniformity, entropy, kurtosis and skewness of the multislice-based texture at different sigma weightings. Statistical significance for these parameters was tested with one-way ANOVA followed by Tukey honestly significant difference (HSD) test. Diagnostic performance was evaluated using the receiver operating characteristic (ROC) curve analysis. RESULTS: There were significant differences in entropy and uniformity at all sigma weightings (P<0.001) among hepatic abscesses, malignant mimickers and simple cysts. The significant difference in kurtosis and skewness was shown at sigma 1.8 and 2.0 weightings (P=0.002-0.006). Tukey HSD test showed that the abscesses had a significantly higher entropy and lower uniformity compared with malignant mimickers (P=0.000-0.004). Entropy (at a sigma 2.0 weighting) had the largest area under the ROC curve (0.888) in differentiating abscesses from malignant mimickers, with a sensitivity of 81.8% and a specificity of 88.0% when the cutoff value was set to 3.64. CONCLUSION: Multislice-based texture analysis may be useful for differentiating pyogenic hepatic abscesses from malignant mimickers.


Assuntos
Meios de Contraste/administração & dosagem , Iohexol/análogos & derivados , Abscesso Hepático Piogênico/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Diagnóstico Diferencial , Feminino , Humanos , Iohexol/administração & dosagem , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos
4.
J Vasc Interv Radiol ; 25(5): 739-46, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24745904

RESUMO

PURPOSE: To prospectively determine the feasibility of flat-detector (FD) computed tomography (CT) perfusion to measure hepatic blood volume (BV) in the angiography suite in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Twenty patients with HCC were investigated with conventional multislice and FD CT perfusion. CT perfusion was carried out on a multislice CT scanner, and FD CT perfusion was performed on a C-arm angiographic system, before transarterial chemoembolization procedures. BV values of conventional and FD CT perfusion were measured within tumors and liver parenchyma. The arterial perfusion portion of CT perfusion BV was extracted from CT perfusion BV by multiplying it by a hepatic perfusion index. Relative values (RVs) for CT perfusion arterial BV and FD CT perfusion BV (FD BV) were defined by dividing BV of tumor by BV of parenchyma. Relationships between BV and RV values of these two techniques were analyzed. RESULTS: In all patients, both perfusion procedures were technically successful, and all 33 HCCs larger than 10 mm were identified with both imaging methods. There were strong correlations between the absolute values of FD BV and CT perfusion arterial BV (tumor, r = 0.903; parenchyma, r = 0.920; both P < .001). Bland-Altman analysis showed a mean difference of -0.15 ± 0.24 between RVs for CT perfusion arterial BV and FD BV. CONCLUSIONS: The feasibility of FD CT perfusion to assess BV values of liver tumor and surrounding parenchyma in the angiographic suite was demonstrated.


Assuntos
Angiografia/métodos , Volume Sanguíneo , Carcinoma Hepatocelular/fisiopatologia , Neoplasias Hepáticas/fisiopatologia , Neovascularização Patológica/fisiopatologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia/instrumentação , Velocidade do Fluxo Sanguíneo , Determinação do Volume Sanguíneo/instrumentação , Determinação do Volume Sanguíneo/métodos , Carcinoma Hepatocelular/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Humanos , Circulação Hepática , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/instrumentação , Adulto Jovem
5.
Radiographics ; 33(5): 1419-33, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24025933

RESUMO

A multilocular cystic hepatic lesion detected at computed tomography (CT) and magnetic resonance (MR) imaging is a common but nonspecific radiologic finding that can cause potential challenges for differential diagnosis. This imaging pattern may be observed in a wide spectrum of common and uncommon neoplastic or nonneoplastic entities. Neoplastic lesions include cystadenoma, cystadenocarcinoma, hepatocellular carcinoma (HCC), metastases, mesenchymal hamartoma, and inflammatory myofibroblastic tumor. Nonneoplastic lesions include hepatic abscess, echinococcal cyst, intrahepatic hematoma, and biloma. The multiple coalescent cysts seen in polycystic liver disease may exhibit an imaging pattern similar to that of a multilocular cystic lesion. Mural nodularity, irregular thickness of the septa, ragged inner surface, and typical enhancement pattern in the solid portion of the lesion are often indicative of malignancy, although multilocular primary or secondary malignant tumors are uncommon. Recognition of the more common necrosis or cystic change of HCC and metastases induced by locoregional or systemic treatment also is important. The nonenhanced cystic component may be composed of different types of fluids (eg, serous, mucinous, proteinaceous, hemorrhagic, bilious, or mixed) or spontaneous or treatment-related necrosis, whereas the septa may be formed by a wide range of tissues depending on the lesion type. An understanding of the CT and MR imaging findings of these lesions and their respective pathologic correlation aids in accurate diagnosis.


Assuntos
Cistos/diagnóstico , Hepatite/diagnóstico , Hepatopatias/diagnóstico , Neoplasias Hepáticas/diagnóstico , Fígado/diagnóstico por imagem , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estatística como Assunto
6.
Eur Radiol ; 22(10): 2178-85, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22622347

RESUMO

OBJECTIVES: To assess the feasibility and value of dual-energy spectral computed tomography (DESCT) imaging for differentiating neoplastic from bland macroscopic portal vein (PV) thrombi. METHODS: Computed tomography (CT) images of 44 patients with macroscopic PV thrombus (bland group, n = 16; neoplastic group, n = 28) were reviewed. Iodine-based material decomposition images in the portal venous phase were reconstructed to compare the iodine indices between groups, including thrombus iodine density (I (T)), thrombus-aorta iodine density ratio (I (T)/I (A)), and thrombus-PV iodine density ratio (I (T)/I (P)). Differential diagnostic performances of DESCT were calculated in the subgroup of 21 patients with histopathological evidence (bland group, n = 12; neoplastic group, n = 9). RESULTS: The iodine indices of the neoplastic group were significantly higher than those in the bland group (P < 0.001). A threshold I (T) of 1.14 mg/mL, I (T)/I (A) of 0.17, and I (T)/I (P) of 0.17 in the portal venous phase yielded 100 %, 88.9 %, and 100 % sensitivity, and 91.7 %, 91.7 %, and 83.3 % specificity, respectively, in differentiating neoplastic from bland PV thrombi. CONCLUSIONS: DESCT imaging with quantification of thrombus iodine density in the portal venous phase appears to be a promising new method for distinguishing neoplastic from bland macroscopic PV thrombi. KEY POINTS: • Differentiating the nature of portal vein thrombus is of great clinical significance. • Iodine-based material decomposition imaging reflects iodine distribution after contrast media administration. • Dual-energy CT with iodine quantification can distinguish bland from neoplastic PV thrombi.


Assuntos
Células Neoplásicas Circulantes , Veia Porta , Trombose/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
7.
Hepatobiliary Pancreat Dis Int ; 11(1): 74-80, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22251473

RESUMO

BACKGROUND: Portal hyperperfusion in the small-for-size (SFS) liver can threaten survival of rabbits. Therefore, it is important to understand the hemodynamic changes in the SFS liver. METHODS: Twenty rabbits were divided into two groups: a control group and a modulation group. The control group underwent an extended hepatectomy. The modulation group underwent the same procedure plus splenectomy to reduce portal blood flow. CT perfusion examinations were performed on all rabbits before and after operation. Perfusion parameter values, especially portal vein perfusion (PVP), were analyzed. RESULTS: PVP in the modulation group was lower than in the control group after operation (P=0.002). In the control group, postoperative PVP increased by 193.7+/-55.1% compared with preoperative PVP. A weak correlation was found between the increased percentage of PVP and resected liver-to-body weight ratio (RLBWR) (r=0.465, P=0.033). In the modulation group, postoperative PVP increased by 101.4+/-32.5%. No correlation was found between the increased percentage of PVP and RLBWR (r=0.167, P=0.644). Correlations were found between PVP and serum alanine aminotransferase, aspartate aminotransferase, and total bilirubin after surgery (P<0.05). CONCLUSION: We successfully evaluated the characteristics of hemodynamic changes as well as the effects of splenectomy in the SFS liver in rabbits by the CT technique.


Assuntos
Hemodinâmica , Hepatectomia/efeitos adversos , Circulação Hepática , Imagem de Perfusão/métodos , Veia Porta/diagnóstico por imagem , Veia Porta/fisiopatologia , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/fisiopatologia , Tomografia Computadorizada por Raios X , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Biomarcadores/sangue , Testes de Função Hepática , Masculino , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Coelhos , Esplenectomia
8.
Zhen Ci Yan Jiu ; 47(4): 349-53, 2022 Apr 25.
Artigo em Zh | MEDLINE | ID: mdl-35486015

RESUMO

OBJECTIVE: To observe the effect of thunder-fire moxibustion combined with meibomian gland massage in improving meibomian gland dysfunction (MGD) and explore its mechanism. METHODS: Seventy-two MGD patients with 144 eyes in the Jinhua Hospital of Traditional Chinese Medicine from February 2019 to January 2021 were selected and randomly divided into an experimental group (n=36,72 eyes) and a control group (n=36, 72 eyes). Patients in the control group received 0.1% fluo-rometholone eye drops and 0.1% sodium hyaluronate eye drops, 1-2 drops per time, four times per day, and the meibomian glands were massaged once per day. Patients in the experimental group received additional thunder-fire moxibustion on the basis of the treatment of the control group, 10 cones per time, once per day. One month after treatment, meibomian gland function was assessed, and the levels of interleukin-6 (IL-6) and prostaglandin E2(PGE2) in tears were detected. RESULTS: After treatment, the scores of Ocular Surface Disease Index, meibomian hyperemia, meibomian gland opening, meibomian gland loss, and meibomian gland secretion function were lower than those before treatment in the two groups, and the scores of the experimental group were lower than those of the control group (P<0.05). After treatment, the tear break-up time and tear meniscus height were higher than those before treatment in the two groups, which were higher in the experimental group than those in the control group (P<0.05). The post-treatment levels of IL-6 and PGE2 were lower than those before treatment in the two groups, and the levels in the experimental group were lower than those in the control group (P<0.05). CONCLUSION: Thunder-fire moxibustion combined with meibomian gland massage can significantly improve the function of the meibomian glands and lower the levels of IL-6 and PGE2 in tears.


Assuntos
Glândulas Tarsais , Moxibustão , Dinoprostona , Humanos , Interleucina-6 , Massagem , Soluções Oftálmicas , Estudos Prospectivos
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 13(10): 820-2, 2011 Oct.
Artigo em Zh | MEDLINE | ID: mdl-22000440

RESUMO

OBJECTIVE: Clinical pathways are standardized, multidisciplinary, integrated management plans. This study aimed to evaluate the efficacy of clinical pathways in children with Rotavirus enteritis. METHODS: Seventy-one children with Rotavirus enteritis were treated according to the clinical pathways. Seventy-five children with Rotavirus enteritis who received routine therapy and nursing interventions served as the control group. The clinical efficacies were compared between the two groups. RESULTS: The average hospitalization duration was shortened, the hospitalization costs were reduced and the parents' satisfaction rate increased in the observed group compared with the control group (P<0.05). CONCLUSIONS: The use of clinical pathways may decrease the hospitalization duration and costs and improve the quality of nursing care and the parents' satisfaction rate in children with Rotavirus enteritis.


Assuntos
Procedimentos Clínicos , Enterite/terapia , Infecções por Rotavirus/terapia , Feminino , Humanos , Lactente , Tempo de Internação , Masculino , Satisfação do Paciente
10.
Abdom Radiol (NY) ; 46(9): 4226-4237, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33914139

RESUMO

Pancreatic ductal adenocarcinomas (PDACs) occasionally have atypical and uncommon imaging presentations that can present a diagnostic dilemma and result in false interpretation. This article aimed to illustrate these CT and MR imaging findings, including isoattenuating PDAC, coexisting acute pancreatitis, PDAC with a cystic feature, groove PDAC, diffuse PDAC, hypointensity on diffusion-weighted imaging (DWI), multifocal PDAC, intratumoral calcification, and extrapancreatic invasion with a barely discernable mass. A subset of PDACs with atypical features are occasionally encountered during routine clinical practice. Knowledge of and attention to these atypical and uncommon variable imaging features may allow radiologists to avoid misinterpretation and a delayed diagnosis.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Pancreatite , Doença Aguda , Carcinoma Ductal Pancreático/diagnóstico por imagem , Meios de Contraste , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Neoplasias Pancreáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X
11.
Abdom Imaging ; 35(5): 522-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19669829

RESUMO

BACKGROUND: To identify hemodynamic alterations in anterior segment of liver graft after living-donor liver transplantation (LDLT) using CT perfusion imaging. METHODS: Perfusion images of 19 recipients 4 weeks after LDLT without reconstruction of the middle hepatic vein (MHV) tributaries were retrospectively identified. According to major MHV tributaries diameter in the right lobe graft, recipients were divided into large (≥ 5 mm) and small size groups (<5 mm). Blood flow (BF), blood volume (BV), and mean transit time (MTT) of anterior and posterior segments were calculated. RESULTS: In large size group, significantly decreased BF (66.98 ± 15.79 mL/min/100 g, corresponded to 37.08%), BV (8.27 ± 2.29 mL/100 g, 41.71%), and increased MTT (11.79 ± 2.10 s, 23.71%) were detected in the anterior segment compared to the posterior segment. In small size group, compared to the posterior segment, BF, BV in the anterior segment decreased 19.12%, 18.48%, respectively, and MTT increased 6.78%, where decreased BF (86.40 ± 21.39 mL/min/100 g) and BV (11.50 ± 2.59 mL/min/100 g) reached statistical significance. Perfusion imbalance in large size group was more remarkable than those in small size group. CONCLUSIONS: CT liver perfusion imaging enabled quantification of hemodynamic alterations in right-lobe liver graft after LDLT. Compared to small ones, ligation of large MHV tributaries could bring about more marked perfusion imbalance between anterior and posterior segments.


Assuntos
Transplante de Fígado/métodos , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Análise de Variância , Velocidade do Fluxo Sanguíneo , Volume Sanguíneo , Estudos de Casos e Controles , Meios de Contraste/administração & dosagem , Feminino , Humanos , Iohexol/administração & dosagem , Iohexol/análogos & derivados , Fígado/cirurgia , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Estatísticas não Paramétricas
12.
Zhonghua Yi Xue Za Zhi ; 90(15): 1054-6, 2010 Apr 20.
Artigo em Zh | MEDLINE | ID: mdl-20646527

RESUMO

OBJECTIVE: To discuss the value of spiral CT in diagnosing infantile intestinal malrotation. METHODS: The spiral CT findings and clinical data of 23 cases of operatively-confirmed infantile intestinal malrotation were retrospectively analyzed. RESULTS: Twenty-three cases of infantile intestinal malrotation were all diagnosed by SCT and confirmed by surgery. The main findings were as follows: whirlpool or concentric circle sign in mesenteric root with midgut volvulus (n = 16); duodenum assumed as "Z" or olecranon spur sign (n = 18); inverted transposition or vertical arrangement of superior mesenteric artery and vein (n = 13); abnormal sign of ileocecal junction and colon in right lower quadrant (n = 23). CONCLUSION: Spiral CT scanning has an important value in the early diagnosis of infantile intestinal malrotation.


Assuntos
Volvo Intestinal/diagnóstico por imagem , Tomografia Computadorizada Espiral , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Volvo Intestinal/congênito , Intestinos/anormalidades , Masculino , Estudos Retrospectivos
13.
Materials (Basel) ; 13(11)2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32517028

RESUMO

Hysteresis of the actuators based on magnetostrictive materials influences the control performance of the application systems. It is of importance and significance to establish an effective hysteresis model for the magnetostrictive actuators for precision engineering. In this paper, based on the analysis of the Duhem model, a first-order inertial system with hysteresis characteristic under harmonic input is used to describe the hysteresis caused by the inertia of the magnetic domains of magnetostrictive materials. Shape function is employed to describe the pinning of domain walls, the interactions of different magnetic domains of magnetostrictive materials, and the saturation properties of the hysteresis. Specifically, under an architecture of "inertial system + shape function" (ISSF-Duhem model), firstly a new hysteresis model is proposed for magnetostrictive actuators. The formulation of the inertial system is constructed based on its general expression, which is capable of describing the hysteresis characteristics of magnetostrictive actuators. Then, the developed models with a Grompertz function-based shape function, a modified hyperbolic tangent function-based shape function employing an exponential function as an offset function, a one-sided dead-zone operator-based shape function are compared with each other, and further compared with the classic modified Prandtl-Ishlinskii model with a one-sided dead-zone operator. Sequentially, feasibility and capability of the proposed hysteresis model are verified and evaluated by describing and predicting the hysteresis characteristics of a commercial magnetostrictive actuator.

14.
Clin Transplant ; 23(5): 692-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19473203

RESUMO

Hepatic hemodynamic changes in grafts after living donor liver transplantation (LDLT) are complicated. In this study, computed tomography (CT) perfusion parameter values, especially portal vein perfusion (PVP), was retrospectively analyzed in recipients both with and without small-for-size syndrome (SFSS). PVP was significantly higher in non-SFSS recipients on post-operative day (POD) 14 or 28 than in normal donors before donation (p < 0.001 and p = 0.008, respectively), but it significantly decreased between 14 and 28 days post-operatively (p = 0.007). There was a significant inverse correlation between graft-to-recipient spleen size ratio and PVP on POD 14 in non-SFSS group (r = -0.545, p = 0.002). Furthermore, PVP in the SFSS group was significantly greater than in the non-SFSS group on POD 14 (p = 0.042). In conclusion, we successfully evaluated normal hemodynamic changes in grafts without SFSS by CT perfusion examination. To our knowledge, this is the first study on hemodynamic changes of living donor liver grafts using CT technique.


Assuntos
Transplante de Fígado , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Doadores Vivos , Tomografia Computadorizada por Raios X , Adulto , Idoso , Ensaio de Imunoadsorção Enzimática , Feminino , Sobrevivência de Enxerto , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Perfusão , Reação em Cadeia da Polimerase , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
15.
Zhongguo Zhen Jiu ; 39(3): 267-70, 2019 Mar 12.
Artigo em Zh | MEDLINE | ID: mdl-30942013

RESUMO

OBJECTIVE: To analyze the effects of intradermal needling for pain and tear film stability in patients after pterygium excision. METHODS: A total of 76 patients (98 affected eyes) with primary pterygium were randomly divided into an observation group (38 cases, 53 affected eyes) and a control group (38 cases, 45 affected eyes).In the control group, only pterygium resection was performed, in the observation group, intradermal needling after pterygium resection was applied at Cuanzhu (BL 2), Yuyao (EX-HN 4), Taiyang (EX-HN 5), Sibai (ST 2), Hegu (LI 4), removed after 24 h and changed three times a week. The pain level of 3 days after surgery, dry eye symptoms, the basic tear secretion test (Schirmer-Ⅰ), and the tear-break time (BUT) changes before surgery, 2 weeks after surgery and 4 weeks after surgery were compared between the two groups, and the clinical efficacy was evaluated. RESULTS: The pain level of 3 days after surgery in the observation group was significantly lower than that in the control group (P<0.05). The dry eye symptom scores at 2 weeks and 4 weeks after surgery in the two groups were significantly lower than those before surgery (all P<0.05), and the dry eye symptom scores in the observation group were significantly lower than those in the control group (both P<0.05). The Schirmer-Ⅰ test at 2 weeks and 4 weeks after surgery was significantly prolonged than that before surgery(all P<0.05), and the Schirmer-Ⅰ test in the observation group was significantly longer than that in the control group (both P<0.05). The BUT at 2 weeks and 4 weeks after surgery in the two groups was significantly longer than that before surgery (all P<0.05), and the BUT in the observation group was significantly longer than that in the control group (both P<0.05). The total effective rate in the observation group was 89.5% (34/38), which was higher than 71.1% (27/38) in the control group (P<0.05). CONCLUSION: Intradermal needling can effectively reduce the pain level of patients after pterygium resection, improve dry eye symptoms, promote the secretion of tears and improve the tear film stability.


Assuntos
Síndromes do Olho Seco , Pterígio , Pontos de Acupuntura , Humanos , Dor , Lágrimas
16.
J Neurol Sci ; 268(1-2): 60-4, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18068726

RESUMO

BACKGROUND: Studies were carried out to detect brain tissue damage in patients with vascular cognitive impairment (VCI) using diffusion tensor imaging (DTI) histogram analysis, and to determine the correlations between DTI histogram-derived measures and Mini-Mental State Examination (MMSE) scores. METHODS: Conventional MRI and DTI scans were performed on 19 patients with VCI, 19 age- and sex-matched post-stroke patients without cognitive impairment (stroke group) and 19 cognitively normal subjects (CN group). Histograms of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of the whole brain were analyzed. RESULTS: Analysis showed that the patterns of the whole brain ADC and FA histograms of the VCI group differed from those of the stroke and CN groups. Compared with those of the two control groups, the mean FA value was significantly lower and the FA histogram peak height was higher in the VCI group. However, the patterns of the whole brain ADC and FA histograms in the stroke group were similar to those of the CN group, and there were no significant differences in any of the DTI histogram-derived measures between these two groups. The mean FA value, the FA histogram peak height, and the FA histogram peak location in VCI patients correlated with the MMSE scores. CONCLUSIONS: Our findings suggest that VCI leads to abnormal diffusion in brain tissue, and that DTI histogram-derived measures might be used to monitor the severity of cognitive impairment in this disease.


Assuntos
Mapeamento Encefálico , Encéfalo/patologia , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Idoso , Análise de Variância , Transtornos Cognitivos/etiologia , Feminino , Humanos , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Doenças Vasculares/complicações , Doenças Vasculares/metabolismo , Doenças Vasculares/patologia
17.
AJR Am J Roentgenol ; 191(1): 290-1, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18562761

RESUMO

OBJECTIVE: The objective of this article is to explain an easy and effective approach for managing radiologic files in portable document format (PDF) using iTunes. CONCLUSION: PDF files are widely used as a standard file format for electronic publications as well as for medical online documents. Unfortunately, there is a lack of powerful software to manage numerous PDF documents. In this article, we explain how to use the hidden function of iTunes (Apple Computer) to manage PDF documents as easily as managing music files.


Assuntos
Sistemas de Gerenciamento de Base de Dados , Processamento Eletrônico de Dados/métodos , Armazenamento e Recuperação da Informação/métodos , Sistemas de Informação em Radiologia , Software
18.
Sci Rep ; 7(1): 2355, 2017 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-28539652

RESUMO

As a newly identified factor in calcium-activated chloride channel, ANO1 participates in various physiological processes like proliferation and differentiation, and expresses in human cardiac fibroblasts. In this experiment, we investigated the function of ANO1 in cardiac fibrosis after myocardial infraction (MI) with methods of Western blotting, Quantitative real-time PCR (qRT-PCR), metabolic reduction of 3-(4,5-dimethylthiozol-2-yl)-2, 5-diphenyltetrazo-lium bromide (MTT), immunofluorescence and confocal imaging, and Masson's trichrome staining. The results showed that the expression of ANO1 significantly increased in neonatal rats' cardiac fibroblasts after hypoxia and in cardiac tissues after MI. After ANO1 over-expression, cardiac fibrosis was reduced in vitro and in vivo. Moreover, the expression of TGF-ß and p-smad3 declined after ANO1over-expression in cardiac fiborblasts. In conclusion, ANO1 inhibits cardiac fibrosis after MI via TGF-ß/smad3 pathway in rats.


Assuntos
Anoctamina-1/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Animais Recém-Nascidos , Anoctamina-1/genética , Hipóxia Celular , Células Cultivadas , Fibroblastos/metabolismo , Fibrose , Expressão Gênica , Masculino , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/genética , Miocárdio/patologia , Ratos Sprague-Dawley , Transdução de Sinais
19.
Sci Rep ; 7(1): 238, 2017 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-28331223

RESUMO

Proprotein convertase subtilisin/kexin9 monoclonal antibodies (PCSK9-mAb) have been studied intensively to identify their effect in lowering levels of low density lipoprotein cholesterol (LDL-C). However, the applicable target of PCSK9-mAbs remains inconclusive so far. Therefore, this first meta-analysis was carried out to clarify the therapeutic efficacy and safety of PCSK9-mAbs on the potential patients: familial hypercholesterolemia and statin-intolerant patients. All randomized controlled trials that met the search terms were retrieved in multiple databases. Efficacy outcomes included parameter changes from baseline in LDL-C and other lipid levels. Therapeutic safety were evaluated by rates of common adverse events. A total of 15 studies encompassing 4,288 patients with at least 8 weeks duration were selected. Overall, the therapeutic efficacy was achieved with significant reduction in LDL-C, TC, TG, Lp(a), Apo-B versus placebo. The decline in familial hypercholesterolemia patients (-53.28%, 95% CI: -59.88 to -46.68%) was even more obvious than that in statin-intolerant patients (-34.95%, 95% CI: -41.46 to -28.45%). No obvious safety difference was found out in the rates of common and serious adverse events. To conclude, PCSK9-mAb contributes to the decreased level of LDL-C and other lipids in familial hypercholesterolemia and statin-intolerant patients with satisfactory safety and tolerability.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Fatores Imunológicos/administração & dosagem , Inibidores de PCSK9 , Anticorpos Monoclonais/efeitos adversos , LDL-Colesterol/sangue , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Humanos , Fatores Imunológicos/efeitos adversos , Placebos/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
20.
Abdom Radiol (NY) ; 42(9): 2233-2242, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28401282

RESUMO

PURPOSE: To determine reliable CT features to distinguish cancerous from inflammatory colorectal perforations. MATERIALS AND METHODS: A total of 43 patients with surgically and pathologically confirmed colorectal perforation caused by either colorectal cancer (n =27) or an inflammatory conditions (n = 16) were identified. Two radiologists independently assessed the contrast-enhanced CT features for locations of perforation, mural configurations, soft-tissue alterations, lymphadenopathy, and metastases. Intergroup comparisons for univariate analysis were performed using Fisher's exact test or chi-square test for categorical data and Mann-Whitney test for numeric data. Stepwise logistic regression analysis was conducted with features that were found significant under the univariate analysis. Interobserver agreement was assessed using intraclass correlation coefficient (ICC) and kappa test. RESULTS: Maximal mural thickness >1.39 cm (sensitivity, 100%; specificity, 68.75%), luminal mass or shoulder formation (sensitivity, 88.89%; specificity, 68.75%), absence of diverticula (sensitivity, 96.30%; specificity, 50.00%), irregular mural thickening (sensitivity, 92.59%; specificity, 81.25%), lymphadenopathy (sensitivity, 40.74%; specificity, 93.75%), and metastases (sensitivity, 25.93%; specificity, 100%) were significantly frequent in cancerous perforations. The maximal mural thickness (P = 0.0493, odds ratio = 439.83) and irregular mural thickening (P = 0.0343, odds ratio = 4.69) were identified as the highly distinguished identifiers. CONCLUSIONS: The CT manifestations of cancerous and inflammatory colorectal perforations overlap. Definitive diagnosis is not always possible with imaging alone. The maximal mural thickness >1.39 cm and irregular configuration of the thickened bowel wall were the two highly statistically significant CT features that may help order the difference between the two entities.


Assuntos
Neoplasias Colorretais/complicações , Neoplasias Colorretais/diagnóstico por imagem , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/diagnóstico por imagem , Perfuração Intestinal/diagnóstico por imagem , Perfuração Intestinal/etiologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Iopamidol , Metástase Linfática/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
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