Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
1.
Liver Int ; 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33647177

RESUMO

BACKGROUND&AIMS: Magnetic resonance imaging (MRI) is the first-line tool for the noninvasive diagnosis of hepatocellular carcinoma (HCC) in patients with chronic liver diseases. We performed a meta-analysis to compare the performance of MRI using extracellular contrast agents (ECA-MRI) with that using gadoxetic acid (EOB-MRI) for diagnosing HCC. METHODS: We searched multiple databases for studies comparing the diagnostic performance of ECA-MRI with that of EOB-MRI in patients with suspected HCC until May 31, 2020. The bivariate random-effects model was used to pool the performance and further subgroup analysis was performed. RESULTS: Eight studies were included evaluating a total of 1002 patients. ECA-MRI revealed significantly higher per-lesion sensitivity in the diagnosis of HCC than EOB-MRI did (0.76 versus 0.63, P = 0.002). For modified EOB-MRI (mEOB-MRI) using extended washout to the transitional phase (TP) or hepatobiliary phase (HBP), the sensitivity increased compared with that of EOB-MRI using restrictive washout in the portal venous phase (PVP) (0.74 versus 0.63, P = 0.07). No significant difference among the specificities of ECA-MRI, EOB-MRI, and mEOB-MRI (0.96, 0.98, and 0.93, respectively) was found. The sensitivity for lesions < 20 mm was significantly lower than that for lesions ≥ 20mm (0.66 versus 0.87, P = 0.01) only for ECA-MRI, which achieved higher sensitivity in Asian patients or with a 3.0 T scanner. CONCLUSIONS: ECA-MRI outperforms EOB-MRI in per-lesion sensitivity for diagnosing HCC, while mEOB-MRI shows a trend toward improved sensitivity compared with EOB-MRI with slightly decreased specificity.

2.
J Gerontol A Biol Sci Med Sci ; 76(3): e78-e84, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33355656

RESUMO

BACKGROUND: Skeletal muscle depletion is common in old adults and individuals with chronic comorbidities, who have an increased risk of developing severe coronavirus disease 2019 (COVID-19), which is defined by hypoxia requiring supplemental oxygen. This study aimed to determine the association between skeletal muscle depletion and clinical outcomes in patients with severe COVID-19. METHODS: One hundred and sixteen patients with severe COVID-19 who underwent chest computed tomography scan on admission were included in this multicenter, retrospective study. Paraspinal muscle index (PMI) and radiodensity (PMD) were measured using computed tomography images. The primary composite outcome was the occurrence of critical illness (respiratory failure requiring mechanical ventilation, shock, or intensive care unit admission) or death, and the secondary outcomes were the duration of viral shedding and pulmonary fibrosis in the early rehabilitation phase. Logistic regression and Cox proportional hazards models were employed to evaluate the associations. RESULTS: The primary composite outcome occurred in 48 (41.4%) patients, who were older and had lower PMD (both p < .05). Higher PMD was associated with reduced risk of critical illness or death in a fully adjusted model overall (odds ratio [OR] per standard deviation [SD] increment: 0.87, 95% confidence interval [CI]: 0.80-0.95; p = .002) and in female patients (OR per SD increment: 0.71, 95% CI: 0.56-0.91; p = .006), although the effect was not statistically significant in male patients (p = .202). Higher PMD (hazard ratio [HR] per SD increment: 1.08, 95% CI: 1.02-1.14; p = .008) was associated with shorter duration of viral shedding among female survivors. However, no significant association was found between PMD and pulmonary fibrosis in the early rehabilitation phase, or between PMI and any outcome in both men and women. CONCLUSIONS: Higher PMD, a proxy measure of lower muscle fat deposition, was associated with a reduced risk of disease deterioration and decreased likelihood of prolonged viral shedding among female patients with severe COVID-19.

3.
Nano Lett ; 21(1): 414-423, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33356313

RESUMO

Salmonella selectively colonizes into the hypoxic tumor region and exerts antitumor effects via multiple mechanisms, while the tumor colonized Salmonella recruits host neutrophils into the tumor, presenting a key immunological restraint to compromise the Salmonella efficacy. Here, we develop a combinatorial strategy by employing silver nanoparticles (AgNPs) to improve the efficacy and biosafety of Salmonella. The AgNPs were decorated with sialic acid (SA) to allow selective recognition of L-selectin on neutrophil surfaces, based on which the tumor-homing of AgNPs was achieved by neutrophil infiltration in the Salmonella colonized tumor. The tumor-targeting AgNPs exert the functions of (1) local depletion of neutrophils in tumors to boost the efficacy of Salmonella, (2) direct killing tumor cells via L-selectin-mediated intracellular delivery, and (3) clearing the residual Salmonella after complete tumor eradication to minimize the side effects. With a single tail vein injection of such combination treatment, the tumor was eliminated with high biosafety, resulting in a superior therapeutic outcome.

4.
Med Image Anal ; 67: 101836, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33129141

RESUMO

The recent global outbreak and spread of coronavirus disease (COVID-19) makes it an imperative to develop accurate and efficient diagnostic tools for the disease as medical resources are getting increasingly constrained. Artificial intelligence (AI)-aided tools have exhibited desirable potential; for example, chest computed tomography (CT) has been demonstrated to play a major role in the diagnosis and evaluation of COVID-19. However, developing a CT-based AI diagnostic system for the disease detection has faced considerable challenges, which is mainly due to the lack of adequate manually-delineated samples for training, as well as the requirement of sufficient sensitivity to subtle lesions in the early infection stages. In this study, we developed a dual-branch combination network (DCN) for COVID-19 diagnosis that can simultaneously achieve individual-level classification and lesion segmentation. To focus the classification branch more intensively on the lesion areas, a novel lesion attention module was developed to integrate the intermediate segmentation results. Furthermore, to manage the potential influence of different imaging parameters from individual facilities, a slice probability mapping method was proposed to learn the transformation from slice-level to individual-level classification. We conducted experiments on a large dataset of 1202 subjects from ten institutes in China. The results demonstrated that 1) the proposed DCN attained a classification accuracy of 96.74% on the internal dataset and 92.87% on the external validation dataset, thereby outperforming other models; 2) DCN obtained comparable performance with fewer samples and exhibited higher sensitivity, especially in subtle lesion detection; and 3) DCN provided good interpretability on the loci of infection compared to other deep models due to its classification guided by high-level semantic information. An online CT-based diagnostic platform for COVID-19 derived from our proposed framework is now available.


Assuntos
/diagnóstico por imagem , Redes Neurais de Computação , Pneumonia Viral/diagnóstico por imagem , Tomografia Computadorizada por Raios X , /classificação , Humanos , Pneumonia Viral/classificação , Radiografia Torácica , Sensibilidade e Especificidade
5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(9): 1109-1114, 2020.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33051426

RESUMO

OBJECTIVES: To investigate volume changes of subcortical structures in patients with post-hepatitis B cirrhosis. METHODS: Thirty patients with post-hepatitis B cirrhosis (the cirrhosis group) and 24 age- and sex-matched healthy controls (the control group) were enrolled in this prospective study. All subjects underwent neuropsychological tests, blood biochemical determinations, and cerebral MRI. Volumes of 18 selected subcortical structures were automatically segmented and analyzed by the FreeSurfer. In the cirrhosis group, the relationships between abnormal subcortical volumes and clinical index or neurocognitive performance were investigated. The relationships between globus pallidus volumes and pallidal hyperintensity were also examined. RESULTS: Compared with the healthy controls, patients with post-hepatitis B cirrhosis displayed smaller bilateral putamen, amygdala, and nucleus accumbens volumes and larger bilateral globus pallidus volumes (P<0.001 or P=0.001). In the cirrhosis group, the volumes of left putamen and amygdala were negatively correlated with the number connection test-A (NCT-A)(left putamen r=-0.410, P=0.034; left amygdala r=-0.439, P=0.022), and the volumes of bilateral globus pallidus were positively correlated with pallidal index (PI) (left globus pallidus r=0.889, P<0.001; right globus pallidus r=0.900, P<0.001). CONCLUSIONS: Abnormalities of subcortical volumes appear bilaterally symmetrical in patients with post-hepatitis B cirrhosis. Atrophy of left putamen and amygdala might contribute to poor neurocognitive performance, and the manganese deposition might contribute to the increased globus pallidus volumes in patients with post-hepatitis B cirrhosis.


Assuntos
Hepatite B , Imagem por Ressonância Magnética , Hepatite B/complicações , Hepatite B/diagnóstico por imagem , Humanos , Cirrose Hepática/diagnóstico por imagem , Testes Neuropsicológicos , Estudos Prospectivos
6.
Nat Commun ; 11(1): 4968, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009413

RESUMO

The outbreak of coronavirus disease 2019 (COVID-19) has rapidly spread to become a worldwide emergency. Early identification of patients at risk of progression may facilitate more individually aligned treatment plans and optimized utilization of medical resource. Here we conducted a multicenter retrospective study involving patients with moderate COVID-19 pneumonia to investigate the utility of chest computed tomography (CT) and clinical characteristics to risk-stratify the patients. Our results show that CT severity score is associated with inflammatory levels and that older age, higher neutrophil-to-lymphocyte ratio (NLR), and CT severity score on admission are independent risk factors for short-term progression. The nomogram based on these risk factors shows good calibration and discrimination in the derivation and validation cohorts. These findings have implications for predicting the progression risk of COVID-19 pneumonia patients at the time of admission. CT examination may help risk-stratification and guide the timing of admission.


Assuntos
Infecções por Coronavirus/diagnóstico , Progressão da Doença , Pneumonia Viral/diagnóstico , Pneumonia , Tomografia Computadorizada por Raios X/métodos , Adulto , Betacoronavirus , China , Técnicas de Laboratório Clínico , Coinfecção , Infecções por Coronavirus/patologia , Infecções por Coronavirus/fisiopatologia , Feminino , Hospitalização , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Linfócitos , Masculino , Pessoa de Meia-Idade , Neutrófilos , Pandemias , Pneumonia Viral/patologia , Pneumonia Viral/fisiopatologia , Análise de Regressão , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
7.
Aging Dis ; 11(5): 1069-1081, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33014523

RESUMO

Coronavirus disease 2019 (COVID-19) is a global pandemic associated with a high mortality. Our study aimed to determine the clinical risk factors associated with disease progression and prolonged viral shedding in patients with COVID-19. Consecutive 564 hospitalized patients with confirmed COVID-19 between January 17, 2020 and February 28, 2020 were included in this multicenter, retrospective study. The effects of clinical factors on disease progression and prolonged viral shedding were analyzed using logistic regression and Cox regression analyses. 69 patients (12.2%) developed severe or critical pneumonia, with a higher incidence in the elderly and in individuals with underlying comorbidities, fever, dyspnea, and laboratory and imaging abnormalities at admission. Multivariate logistic regression analysis indicated that older age (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.02-1.06), hypertension without receiving angiotensinogen converting enzyme inhibitors or angiotensin receptor blockers (ACEI/ARB) therapy (OR, 2.29; 95% CI, 1.14-4.59), and chronic obstructive pulmonary disease (OR, 7.55; 95% CI, 2.44-23.39) were independent risk factors for progression to severe or critical pneumonia. Hypertensive patients without receiving ACEI/ARB therapy showed higher lactate dehydrogenase levels and computed tomography (CT) lung scores at about 3 days after admission than those on ACEI/ARB therapy. Multivariate Cox regression analysis revealed that male gender (hazard ratio [HR], 1.22; 95% CI, 1.02-1.46), receiving lopinavir/ritonavir treatment within 7 days from illness onset (HR, 0.75; 95% CI, 0.63-0.90), and receiving systemic glucocorticoid therapy (HR, 1.79; 95% CI, 1.46-2.21) were independent factors associated with prolonged viral shedding. Our findings presented several potential clinical factors associated with developing severe or critical pneumonia and prolonged viral shedding, which may provide a rationale for clinicians in medical resource allocation and early intervention.

8.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(7): 827-833, 2020 Jul 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32879086

RESUMO

OBJECTIVES: Quantitative magnetic resonance imaging has been successfully applied to assess the status of cartilage biochemical components. This study aimed to investigate the performance of 3.0T magnetic resonance imaging T2 mapping combined with texture analysis for evaluating the early degeneration of lumbar facet joints. METHODS: A total of 38 patients (20 in the asymptomatic group and 18 in the symptomatic group) were enrolled. All patients underwent 3.0T magnetic resonance imaging conventional sequences, water excitation three-dimensional spoiled gradient echo sequence (3D-WATSc), and T2 mapping scans. The bilateral L4/5 and L5/S1 lumbar facet joints were morphological graded using the Weishaupt criteria, T2 values, and texture parameters derived from T2 mapping of cartilage. The Kruskal-Wallis H test was used to compare the differences of parameters among different groups. Multivariate logistic regression analysis was used to obtain the independent predictive factors for evaluating the early degeneration of lumbar facet joints. Receiver operating characteristic (ROC) curve was performed and the area under curve (AUC) was calculated. Spearman correlation analysis was used to evaluate the correlation of the independent predictors of cartilage T2 value and texture parameters with the subjects' Japanese Orthopedic Association (JOA) score or Visual Analogue Scale (VAS) score. RESULTS: A total of 148 facet joints were selected, including 70 in Weishaupt 0 (normal) group, 58 in Weishaupt 1 group, and 20 in Weishaupt 2-3 group. T2 value, entropy, and contrast increased significantly as the exacerbation of facet joint degeneration (all P<0.05), while the inverse difference moment, energy, and correlation decreased (all P<0.05). Entropy among different groups was significantly different (all P<0.05), and the differences of T2 value, contrast, inverse difference moment, and energy between Weishaupt 0 and Weishaupt 1 groups, or Weishaupt 0 and Weishaupt 2-3 groups were statistically significant (all P<0.05). Multivariate logistic regression analysis suggested that T2 value and inverse difference moment were the independent predictors for evaluating early degeneration of facet joints. The combination of T2 value with inverse difference moment achieved the best performance in distinguishing Weishaupt 0 from Weishaupt 1 (AUC=0.85), with sensitivity and specificity at 92.7% and 76.5%, respectively. In the symptom group, the cartilage T2 value combined inverse difference moment was positively correlated with JOA score (r=0.475, P<0.05) and VAS score (r=0.452, P<0.05). CONCLUSIONS: 3.0T magnetic resonance imaging T2 mapping combined with texture analysis is helpful to quantitatively evaluate the early degeneration of lumbar facet joints, in which the T2 value and inverse difference moment show an indicative significance..


Assuntos
Espondilose , Articulação Zigapofisária , Algoritmos , Humanos , Vértebras Lombares , Imagem por Ressonância Magnética , Sensibilidade e Especificidade
9.
Cell Transplant ; 29: 963689720934413, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32543895

RESUMO

Islet transplantation is a promising ß-cell replacement therapy for type 1 diabetes, which can reduce glucose lability and hypoglycemic episodes compared with standard insulin therapy. Despite the tremendous progress made in this field, challenges remain in terms of long-term successful transplant outcomes. The insulin independence rate remains low after islet transplantation from one donor pancreas. It has been reported that the islet-related inflammatory response is the main cause of early islet damage and graft loss after transplantation. The production of interleukin-1ß (IL-1ß) has considered to be one of the primary harmful inflammatory events during pancreatic procurement, islet isolation, and islet transplantation. Evidence suggests that the innate immune response is upregulated through the activity of Toll-like receptors and The NACHT Domain-Leucine-Rich Repeat and PYD-containing Protein 3 inflammasome, which are the starting points for a series of signaling events that drive excessive IL-1ß production in islet transplantation. In this review, we show recent contributions to the advancement of knowledge of IL-1ß in islet transplantation and discuss several strategies targeting IL-1ß for improving islet engraftment.

10.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(3): 262-268, 2020 Mar 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32386017

RESUMO

OBJECTIVES: To investigate imaging features of the coronavirus disease 2019 (COVID-19), and to provide concrete evidences for diagnosis of COVID-19. METHODS: Imaging data of the first chest CT examination and clinical data (age, sex, clinical history, epidemiological history, and laboratory tests) of 163 patients with COVID-19 from 2 hospitals were collected for retrospective analysis. Imaging features of the first chest CT examination and the correspondence between CT manifestations and the nucleic acid test results of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were analyzed. RESULTS: The first chest CT images of 163 COVID-19 patients showed that 92.02% of lesions were ground-glass opacity (GGO), 76.69% were consolidation, and 73.62% were GGO together with consolidation. Multiple lesions were found in 71.17% patients and multiple lobules in 86.50% patients. Lesions in 53.37% patients were found with bronchial inflation signs and those in 36.20% patients presented with "crazy paving" pattern, while only 7.36% were found with hilar node enlargement and pleural effusion. First CT findings of 18 patients were found to be inconsistent with the results of pathogen examination. CONCLUSIONS: COVID-19 patients showed specific features in the first chest CT examination. The combination of the first chest CT imaging features and SARS-CoV-2 nucleic acid test results as well as reexamination if necessary can help to make the diagnosis of SARS-CoV-2 infection accurately.


Assuntos
Betacoronavirus , Infecções por Coronavirus/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Humanos , Pandemias , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
11.
Mater Sci Eng C Mater Biol Appl ; 111: 110827, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279755

RESUMO

Mesenchymal stem cells (MSCs) hold great promise in the field of regenerative medicine, and great effort goes into investigating the mechanisms underlying their therapeutic effects. These investigations necessitate the development of sensitive and reliable methods of tracking stem cells. As the unique physicochemical properties of ß-NaGdF4:Yb/Er upconversion nanoparticles make them highly efficient fluorescent probes, they could be utilized to track stem cells through bio-imaging. However, their biocompatibility constitutes a major challenge to their use in biomedical applications. In this paper, we prepared ligand-free spherical ß- NaGdF4:Yb/Er nanoparticles of two different sizes (~15 and ~30 nm in diameter) and investigated their internalization into rat bone marrow-derived MSCs (rBMSCs), as well as their effects on cell proliferation, osteogenic and adipogenic differentiation. Even though particles of both sizes were efficiently taken up by the cells, the larger particles had a stronger fluorescence intensity but their proliferation was not significantly affected; this makes them superior for cell imaging. Analysis of multiple markers revealed that the nanoparticles, especially the larger ones, promoted the process of osteogenic differentiation. In contrast, adipogenesis was slightly hindered by the larger particles, whereas the smaller ones did not affect the process. As a whole, this study suggests that ligand-free spherical ß-NaGdF4:Yb/Er particles of appropriate size are compatible with stem cell proliferation and differentiation, which makes them promising agents for biomedical applications.

12.
Clin Nutr ; 39(10): 3132-3139, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32057535

RESUMO

BACKGROUND & AIMS: Sarcopenia is associated with a higher rate of complications and is an independent predictor of poor outcomes in cirrhosis. The aim of this study was to investigate the association between sarcopenia and the risk of hepatocellular carcinoma (HCC) among patients with cirrhosis. METHODS: Four hundred and ninety-two patients with cirrhosis and no evidence of HCC from 2008 to 2017 were enrolled, who had baseline abdominal computed tomography (CT) analyzed for identification of sarcopenia according to the previously established sex-specific cutoffs. The main endpoint of follow-up was the occurrence of HCC. RESULTS: The majority of patients were male (365/492, 74.2%), and sarcopenia were present in 238 (48.4%) patients at baseline. During a median follow-up of 3.6 years, 54 (11.0%) patients developed HCC. The cumulative incidence of HCC was significantly higher in male patients with sarcopenia than those without sarcopenia (P = 0.001), but not in female patients (P = 0.26). Multivariate Cox regression analysis showed that sarcopenia (hazard ratio [HR], 2.27; 95% confidence interval [CI], 1.09-4.74) was a significant independent factor for HCC development in male patients with cirrhosis, which was consistently identified through competing-risk analysis (subdistribution HR, 2.20; 95% CI, 1.02-4.72). After propensity score matching, male cirrhotic patients with sarcopenia still had a higher risk of HCC than those without sarcopenia (P = 0.02). CONCLUSION: Sarcopenia is associated with an increased risk of developing HCC among male patients with cirrhosis. Therefore, nutritional assessment and necessary interventions in specific cirrhotic patients need to be valued.

15.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(9): 1055-1062, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31645497

RESUMO

OBJECTIVE: To establish a radiomics signature based on CT images of non-small cell lung cancer (NSCLC) to predict the expression of molecular marker P63.
 Methods: A total of 245 NSCLC patients who underwent CT scans were retrospectively included. All patients were confirmed by histopathological examinations and P63 expression were examined within 2 weeks after CT examination. Radiomics features were extracted by MaZda software and subjective image features were defined from original non-enhanced CT images. The Lasso-logistic regression model was used to select features and develop radiomics signature, subjective image features model, and combined diagnostic model. The predictive performance of each model was evaluated by the receiver operating characteristic (ROC) curve, and compared with Delong test.
 Results: Of the 245 patients, 96 were P63 positive and 149 were P63 negative. The subjective image feature model consisted of 6 image features. Through feature selection, the radiomics signature consisted of 8 radiomics features. The area under the ROC curves of the subjective image feature model and the radiomics signature in predicting P63 expression statue were 0.700 and 0.755, respectively, without a significant difference (P>0.05). The combined diagnostic model showed the best predictive power (AUC=0.817, P<0.01).
 Conclusion: The radiomics-based CT scan images can predict the expression status of NSCLC molecular marker P63. The combination of the radiomics features and subjective image features can significantly improve the predictive performance of the predictive model, which may be helpful to provide a non-invasive way for understanding the molecular information for lung cancer cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Biomarcadores Tumorais , Humanos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
16.
J Cancer ; 10(20): 4765-4776, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598148

RESUMO

Bacterial-mediated cancer therapy (BMCT) has become a hot topic in the area of antitumor treatment. Salmonella has been recommended to specifically colonize and proliferate inside tumors and even inhibit tumor growth. Salmonella typhimurium (S. typhimurium) is one of the most promising mediators, which can be easily manipulated. S. typhimurium has been engineered and designed as cancer-targeting therapeutics, and can be improved by combining with other therapeutic methods, e.g. chemotherapy and radiotherapy, which regulate the tumor microenvironment synergistically. In view of all these strengths, the engineered attenuated strains have significant advantages for tumor diagnosis and treatment. This treatment has also been approved by the FDA for clinical trial. In this review, we summarized the recent progress and research in the field of Salmonella -mediated cancer therapy.

17.
Front Neurosci ; 13: 731, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379485

RESUMO

Background and Purpose: Previous neuroimaging studies have demonstrated type 2 diabetes (T2D)-related brain structural and functional changes are partly associated with cognitive decline. However, less is known about the underlying mechanisms. Chronic hyperglycemia and microvascular complications are the two of most important risk factors related to cognitive decline in diabetes. Cerebral small vessel diseases (CSVDs), such as those defined by lacunar infarcts, white matter hyperintensities (WMHs) and microhemorrhages, are also associated with an increased risk of cognitive decline and dementia. In this study, we examined brain magnetic resonance imaging (MRI) changes in patients in the early stages of T2D without CSVDs to focus on glucose metabolism factors and to avoid the interference of vascular risk factors on T2D-related brain damage. Methods: T2D patients with disease durations of less than 5 years and without any signs of CSVDs (n = 34) were compared with healthy control subjects (n = 24). Whole-brain region-based functional connectivity was analyzed with network-based statistics (NBS), and brain surface morphology was examined. In addition, the Montreal Cognitive Assessment (MoCA) was conducted for all subjects. Results: At the whole-brain region-based functional connectivity level, thirty-three functional connectivities were changed in T2D patients relative to those in controls, mostly manifested as pathological between-network positive connectivity and located mainly between the sensory-motor network and auditory network. Some of the connectivities were positively correlated with blood glucose level, insulin resistance, and MoCA scores in the T2D group. The network-level analysis showed between-network hyperconnectivity in T2D patients, but no significant changes in within-network connectivity. In addition, there were no significant differences in MoCA scores or brain morphology measures, including cortical thickness, surface area, mean curvature, and gray/white matter volume, between the two groups. Conclusion: The findings indicate that pathological between-network positive connectivity occurs in the early stages of T2D without CSVDs. The abnormal connectivity may indicate that the original balance of mutual antagonistic/cooperative relationships between the networks is broken, which may be a neuroimaging basis for predicting cognitive decline in early T2D patients.

18.
Eur J Radiol ; 118: 32-37, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31439255

RESUMO

PURPOSE: To explore the feasibility and performance of machine learning-based radiomics classifier to predict the cell proliferation(Ki-67)in non-small cell lung cancer (NSCLC). METHODS: 245 histopathological confirmed NSCLC patients who underwent CT scans were retrospectively included. The Ki-67 proliferation index (Ki-67 PI) were measured within 2 weeks after CT scans. A lesion volume of interest (VOI) was manually delineated and radiomics features were extracted by MaZda software from CT images. A random forest feature selection algorithm (RFFS) was used to reduce features. Six kinds of machine learning methods were used to establish radiomics classifiers, subjective imaging feature classifiers and combined classifiers, respectively. The performance of these classifiers was evaluated by the receiver operating characteristic curve (ROC) and compared with Delong test. RESULTS: 103 radiomics features were extracted and 20 optimal features were selected using RFFS. Among the radiomics classifiers established by six machine learning methods, random forest-based radiomics classifier achieved the best performance (AUC = 0.776) in predicting the Ki-67 expression level with sensitivity and specificity of 0.726 and 0.661, which was better than that of subjective imaging classifiers (AUC = 0.625, P < 0.05). However, the combined classifiers did not improve the predictive performance (AUC = 0.780, P > 0.05), with sensitivity and specificity of 0.752 and 0.633. CONCLUSIONS: The machine learning-based CT radiomics classifier in NSCLC can facilitate the prediction of the expression level of Ki-67 and provide a novel non-invasive strategy for assessing the cell proliferation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Proliferação de Células , Neoplasias Pulmonares/diagnóstico por imagem , Aprendizado de Máquina , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
19.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(5): 469-476, 2019 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-31303608

RESUMO

OBJECTIVE: To explore the feasibility and clinical value of CT-based arterial enhancement fraction (AEF) for evaluating liver function in liver cirrhosis patients.
 Methods: Fifty-two patients with liver cirrhosis (Child-Pugh A, B, and C group included 13, 20, and 19 patients, respectively) and 17 patients without liver diseases as control were prospectively enrolled, respectively. All individuals underwent three-phase hepatic CT, and the color mapping of AEF were obtained in CT kinetics software, as well as the corresponding parameters, i.e., hepatic AEF (HAEF) and the ratio of HAEF to spleen AEF (H/S). The AEF parameters were compared among different groups, and the area under the receiver operating characteristic curve (AUROC) was calculated. The Spearman correlation analysis was performed between the AEF parameters and model for end-stage liver disease (MELD) score in liver cirrhosis patients.
 Results: The interobserver agreement of HAEF and H/S were perfect, and the intraclass correlation coefficient (ICC) were 0.918 (95% CI 0.871 to 0.949), 0.946 (95% CI 0.915 to 0.966), respectively. The HAEF and H/S among those groups were significant different (both P<0.001), and they elevated with the increase of Child-Pugh classification in liver cirrhosis patients (all P<0.05, except the H/S between Child-Pugh A and B). In all patients with liver cirrhosis, the AUROC of HAEF and H/S were 0.933 and 0.821 for Child-Pugh A, and were 0.925 and 0.915 for Child-Pugh C, respectively. The HAEF and H/S of patients with liver cirrhosis were significantly correlated with the MELD score (HAEF: r=0.752, P<0.001; H/S: r=0.676, P<0.001).
 Conclusion: CT-based AEF parameters including HAEF and H/S are closely associated with the severity and prognosis of patients with liver cirrhosis, which have the potential to estimate the liver function in liver cirrhosis patients quantitatively and effectively.


Assuntos
Cirrose Hepática , Humanos , Cirrose Hepática/diagnóstico por imagem , Testes de Função Hepática , Tomografia Computadorizada por Raios X
20.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(5): 507-514, 2019 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-31303613

RESUMO

OBJECTIVE: To establish a three-dimensional finite element model (FEM) of the neck, to analyze the differences in neck biomechanics between patient with cervical spondylotic myelopathy (CSM) and healthy subject and to provide biomechanics basis for the pathogenesis of CSM.
 Methods: A patient with CSM was enrolled in a mechanical simulation experiment. Three-dimensional CT scan was performed, and three-dimensional FEM of the neck was constructed. A heathy subject was selected as a control according to the patient's age, gender, height, and weight. Three-dimensional FEM was used to compare the stress differences in the vertebral body, intervertebral disc, ligament and spinal cord under the normal stress of the cervical spine and the maximum stress of the posterior reclining motion.
 Results: Successfully constructed FEM model of CSM patient and control, and performed mechanical analysis, the most obvious difference in cervical vertebral body force was at C5-C6 segment in CSM patients. The maximum stress site of control and patient was at the anterior edge of the vertebral body. The maximum stress of the vertebral body in the CSM patient was less than that of the control. The stress distribution of the intervertebral disc was irregular in the CSM patient, and the maximum stress was concentrated on both sides of the posterior edge of the intervertebral disc. The stress distribution of the ligaments of the CSM patient was uneven. The maximum stress was in the posterior longitudinal ligament. The range of neck movement in extension of the CSM patient was restricted.
 Conclusion: Compared with the healthy subject, the balance of the vertebral body, intervertebral disc, ligament and limited range of motion of the CSM patient has been changed, which may be related to the mechanical pathogenesis of cervical spondylotic myelopathy.


Assuntos
Disco Intervertebral , Doenças da Medula Espinal , Vértebras Cervicais , Análise de Elementos Finitos , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA