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1.
Front Aging Neurosci ; 16: 1397896, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38832074

RESUMO

Objectives: The altered neuromelanin in substantia nigra pars compacta (SNpc) is a valuable biomarker in the detection of early-stage Parkinson's disease (EPD). Diagnosis via visual inspection or single radiomics based method is challenging. Thus, we proposed a novel hybrid model that integrates radiomics and deep learning methodologies to automatically detect EPD based on neuromelanin-sensitive MRI, namely short-echo-time Magnitude (setMag) reconstructed from quantitative susceptibility mapping (QSM). Methods: In our study, we collected QSM images including 73 EPD patients and 65 healthy controls, which were stratified into training-validation and independent test sets with an 8:2 ratio. Twenty-four participants from another center were included as the external validation set. Our framework began with the detection of the brainstem utilizing YOLO-v5. Subsequently, a modified LeNet was applied to obtain deep learning features. Meanwhile, 1781 radiomics features were extracted, and 10 features were retained after filtering. Finally, the classified models based on radiomics features, deep learning features, and the hybrid of both were established through machine learning algorithms, respectively. The performance was mainly evaluated using accuracy, net reclassification improvement (NRI), and integrated discrimination improvement (IDI). The saliency map was used to visualize the model. Results: The hybrid feature-based support vector machine (SVM) model showed the best performance, achieving ACC of 96.3 and 95.8% in the independent test set and external validation set, respectively. The model established by hybrid features outperformed the one radiomics feature-based (NRI: 0.245, IDI: 0.112). Furthermore, the saliency map showed that the bilateral "swallow tail" sign region was significant for classification. Conclusion: The integration of deep learning and radiomic features presents a potent strategy for the computer-aided diagnosis of EPD. This study not only validates the accuracy of our proposed model but also underscores its interpretability, evidenced by differential significance across various anatomical sites.

2.
Neuroradiology ; 66(5): 775-784, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38294728

RESUMO

PURPOSE: Gliomas are the most common primary brain tumor. Currently, topological alterations of whole-brain functional network caused by gliomas are not fully understood. The work here clarified the topological reorganization of the functional network in patients with unilateral frontal low-grade gliomas (LGGs). METHODS: A total of 45 patients with left frontal LGGs, 19 with right frontal LGGs, and 25 healthy controls (HCs) were enrolled. All the resting-state functional MRI (rs-fMRI) images of the subjects were preprocessed to construct the functional network matrix, which was used for graph theoretical analysis. A two-sample t-test was conducted to clarify the differences in global and nodal network metrics between patients and HCs. A network-based statistic approach was used to identify the altered specific pairs of regions in which functional connectivity in patients with LGGs. RESULTS: The local efficiency, clustering coefficient, characteristic path length, and normalized characteristic path length of patients with unilateral frontal LGGs were significantly lower than HCs, while there were no significant differences of global efficiency and small-worldness between patients and HCs. Compared with the HCs, betweenness centrality, degree centrality, and nodal efficiency of several brain nodes were changed significantly in patients. Around the tumor and its adjacent areas, the inter- and intra-hemispheric connections were significantly decreased in patients with left frontal LGGs. CONCLUSION: The patients with unilateral frontal LGGs have altered global and nodal network metrics and decreased inter- and intra-hemispheric connectivity. These topological alterations may be involved in functional impairment and compensation of patients.


Assuntos
Mapeamento Encefálico , Glioma , Humanos , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Rede Nervosa , Encéfalo/patologia , Glioma/patologia
3.
Clin Interv Aging ; 19: 1-10, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38192377

RESUMO

Background: The effect of Ommaya reservoirs on the clinical outcomes of patients with intraventricular hemorrhage (IVH) remains unclear. Objective: We aimed to determine the effect of combining the Ommaya reservoir and external ventricular drainage (EVD) therapy on IVH and explore better clinical indicators for Ommaya implantation. Methods: A retrospective analysis was conducted on patients diagnosed with IVH who received EVD-Ommaya drainage between January 2013 and March 2021. The patient population was divided into two groups: the Ommaya-used group, comprising patients in whom the Ommaya drainage system was activated post-surgery, and the Ommaya-unused group, comprising patients in whom the system was not activated. The study analyzed clinical, imaging, and outcome data of the patient population. Results: A total of 123 patients with IVH were included: 75 patients in the Ommaya-used group and 48 patients in the Ommaya-unused group. The patients in the Ommaya-used group showed a lower 3-month GOS than those in the Ommaya-unused group (p<0.0001). The modified Graeb scale (mGS) in the Ommaya-unused group was significantly lower than that in the Ommaya-used group before the operation (p<0.01) but not after surgery (p>0.05). The GCS in the Ommaya-unused group was significantly lower than that in the other group, and there was a close correlation between the GCS and 3-month GOS (p<0.0001). The GCS score showed significance in predicting the use of Ommaya (p<0.001). Conclusion: The study demonstrated that combining EVD and Ommaya drainage was a safe and feasible treatment for IVH. Additionally, preoperative GCS was found to predict the use of Ommaya drainage in subsequent treatment, providing valuable information for pre-surgery decision-making.


Assuntos
Hemorragia Cerebral , Drenagem , Humanos , Hemorragia Cerebral/cirurgia , Drenagem/métodos , Sistemas de Liberação de Medicamentos , Estudos Retrospectivos
4.
Front Neurosci ; 16: 980135, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389251

RESUMO

Objectives: To identify preoperative prognostic factors for acute ischemic stroke (AIS) patients receiving mechanical thrombectomy (MT) and compare the performance of quantitative collateral score (qCS) and visual collateral score (vCS) in outcome prediction. Methods: Fifty-five patients with AIS receiving MT were retrospectively enrolled. qCS was defined as the percentage of the volume of collaterals of both hemispheres. Based on the dichotomous outcome assessed using a 90-day modified Rankin Scale (mRS), we compared qCS, vCS, age, sex, National Institute of Health stroke scale score, etiological subtype, platelet count, international normalized ratio, glucose levels, and low-density lipoprotein cholesterol (LDL-C) levels between favorable and unfavorable outcome groups. Logistic regression analysis was performed to determine the effect on the clinical outcome. The discriminatory power of qCS, vCS, and their combination with cofounders for determining favorable outcomes was tested with the area under the receiver-operating characteristic curve (AUC). Results: vCS, qCS, LDL-C, and age could all predict clinical outcomes. qCS is superior over vCS in predicting favorable outcomes with a relatively higher AUC value (qCS vs. vCS: 0.81 vs. 0.74) and a higher sensitivity rate (qCS vs. vCS: 72.7% vs. 40.9%). The prediction power of qCS + LDL-C + age was best with an AUC value of 0.91, but the accuracy was just increased slightly compared to that of qCS alone. Conclusion: Collateral scores, LDL-C and age were independent prognostic predictors for patients with AIS receiving MT; qCS was a better predictor than vCS. Furthermore, qCS + LDL-C + age offers a strong prognostic prediction power and qCS alone was another good choice for predicting clinical outcome.

5.
Eur J Radiol ; 156: 110500, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36099834

RESUMO

PURPOSE: To compare ischemic core volume (ICV) and penumbra volume (PV) measured by MIStar, F-STROKE, and Syngo.via with that measured by RAPID in acute ischemic stroke (AIS), and their concordance in selecting patients for endovascular thrombectomy (EVT). METHODS: Computed tomography perfusion (CTP) data were processed with four software packages. Bland-Altman analysis and intraclass correlation coefficient (ICC) were performed to evaluate their agreement in quantifying ICV and PV. Kappa test was conducted to assess consistency in the selection of EVT candidates. The correlation between predicted ICV and segmented final infarct volume (FIV) on follow-up images was investigated. RESULTS: A total of 91 patients were retrospectively included. F-STROKE had the best consistency with RAPID (ICV: ICC = 0.97; PV: ICC = 0.84) and Syngo.via had the worst consistency (ICV: ICC = 0.77; PV: ICC = 0.66). F-STROKE had the narrowest limits of agreements both in ICV (-27.02, 24.40 mL) and PV (-85.59, 101.80 mL). When selecting EVT candidates, MIStar (kappa = 0.71-0.88) and F-STROKE (kappa = 0.84-0.90) had good to excellent consistency with RAPID, while Syngo.via had poor consistency (kappa = 0.20-0.41). ICV predicted by MIStar was correlated strongest with FIV (r = 0.77). CONCLUSIONS: F-STROKE is most consistent with RAPID in quantitative ICV and PV. F-STROKE and MIStar exhibit similar EVT candidate selection to RAPID. Syngo.via, for its part, seems to have overestimated ICV and underestimated PV, leading to an overly restrictive selection of EVT candidates.

6.
Epilepsy Res ; 186: 107000, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36037622

RESUMO

OBJECTIVE: To develop a functionalized PEG-PLA nanoparticle system containing ketoconazole (KCZ) to overcome the overactivity of pregnane X receptor (PXR) for the treatment of drug-resistant epilepsy (DRE). SIGNIFICANCE: KCZ was developed as a therapy strategy for DRE limited by its lethal hepatotoxicity and minute brain concentration. KCZ-incorporated nanoparticles modified with angiopep-2 (NPs/KCZ) could reduce adverse effects of KCZ and achieve epileptic foci-targeted drug delivery. METHODS: NPs/KCZ was prepared by thin-film hydration method and characterized in vitro and in vivo. The efficacy evaluation of NPs/KCZ was evaluated in a kainic acid (KA)-induced mice model of epilepsy with carbamazepine (CBZ) treatment. RESULTS: The mean particle size and Zeta potential of NPs/KCZ were 17.84 ± 0.33 nm and - 2.28 ± 0.12 mV, respectively. The drug-loading (DL%) of KCZ in nanoparticles was 8.96 ± 0.12 % and the entrapment efficiency (EE%) was 98.56 ± 0.02 %. The critical value of critical micelle concentration was 10-3.3 mg/ml. No obvious cytotoxicity was found in vitro. The behavioral and electrographic seizure activities were obviously attenuated in NPs/KCZ+CBZ group. The CBZ concentration of brain tissues in mice treated with NPs/KCZ+CBZ was significantly increased than those treated with CBZ alone (P = 0.0028). A significantly decreased expression level of PXR and its downstream proteins was observed in NPs/KCZ+CBZ group compared with that in the control and CBZ group (All P < 0.05). CONCLUSION: Our results showed that NPs/KCZ achieved the epileptic foci-targeted delivery of KCZ and ameliorated the efficacy of CBZ on DRE by attenuating the overactivity of PXR.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Nanopartículas , Animais , Encéfalo/metabolismo , Carbamazepina/farmacologia , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Epilepsia Resistente a Medicamentos/metabolismo , Epilepsia/metabolismo , Ácido Caínico/farmacologia , Cetoconazol/farmacologia , Cetoconazol/uso terapêutico , Camundongos , Micelas , Polietilenoglicóis , Receptor de Pregnano X/metabolismo
7.
Front Neurol ; 13: 871613, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35645982

RESUMO

Glioma is the most common primary malignant brain tumor in adults. It accounts for about 75% of such tumors and occurs more commonly in men. The incidence rate has been increasing in the past 30 years. Moreover, the 5-year overall survival rate of glioma patients is < 35%. Different locations, grades, and molecular characteristics of gliomas can lead to different behavioral deficits and prognosis, which are closely related to patients' quality of life and associated with neuroplasticity. Some advanced magnetic resonance imaging (MRI) technologies can explore the neuroplasticity of structural, topological, biochemical metabolism, and related mechanisms, which may contribute to the improvement of prognosis and function in glioma patients. In this review, we summarized the studies conducted on structural and topological plasticity of glioma patients through different MRI technologies and discussed future research directions. Previous studies have found that glioma itself and related functional impairments can lead to structural and topological plasticity using multimodal MRI. However, neuroplasticity caused by highly heterogeneous gliomas is not fully understood, and should be further explored through multimodal MRI. In addition, the individualized prediction of functional prognosis of glioma patients from the functional level based on machine learning (ML) is promising. These approaches and the introduction of ML can further shed light on the neuroplasticity and related mechanism of the brain, which will be helpful for management of glioma patients.

8.
World J Gastroenterol ; 28(20): 2176-2183, 2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35721882

RESUMO

Hepatocellular carcinoma (HCC) is the most common primary liver cancer, accounting for about 90% of liver cancer cases. It is currently the fifth most common cancer in the world and the third leading cause of cancer-related mortality. Moreover, recurrence of HCC is common. Microvascular invasion (MVI) is a major factor associated with recurrence in postoperative HCC. It is difficult to evaluate MVI using traditional imaging modalities. Currently, MVI is assessed primarily through pathological and immunohistochemical analyses of postoperative tissue samples. Needle biopsy is the primary method used to confirm MVI diagnosis before surgery. As the puncture specimens represent just a small part of the tumor, and given the heterogeneity of HCC, biopsy samples may yield false-negative results. Radiomics, an emerging, powerful, and non-invasive tool based on various imaging modalities, such as computed tomography, magnetic resonance imaging, ultrasound, and positron emission tomography, can predict the HCC-MVI status preoperatively by delineating the tumor and/or the regions at a certain distance from the surface of the tumor to extract the image features. Although positive results have been reported for radiomics, its drawbacks have limited its clinical translation. This article reviews the application of radiomics, based on various imaging modalities, in preoperative evaluation of HCC-MVI and explores future research directions that facilitate its clinical translation.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Microvasos/diagnóstico por imagem , Microvasos/patologia , Invasividade Neoplásica/patologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
10.
Chin Med J (Engl) ; 133(12): 1436-1444, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32472783

RESUMO

BACKGROUND: Degree of mucosal recovery is an important indicator for evaluating the therapeutic effects of drugs in treatment of inflammatory bowel disease (IBD). Increasing evidences has proved that tight junction (TJ) barrier dysfunction is one of the pathological mechanisms of IBD. The aim of this study was to observe whether enhancement of TJ can decrease colitis recurrence. METHODS: Eighty C57BL/6 mice were randomly divided into four groups including normal group, colitis group, sulfasalazine (SASP) treated group, and traditional Chinese drug salvianolic acid B (Sal B) treated group. Colitis was established in mice by free drinking water containing dextran sulfate sodium, after treatments by SASP and Sal B, recombinant human interleukin-1ß (IL-1ß) was injected intraperitoneally to induce colitis recurrence. RESULTS: Compared with sham control, cell apoptosis in colitis group was increased from 100.85 ±â€Š3.46% to 162.89 ±â€Š11.45% (P = 0.0038), and TJ dysfunction marker myosin light chain kinase (MLCK) was also significantly increased from 99.70 ±â€Š9.29% to 296.23 ±â€Š30.78% (P = 0.0025). The increased cell apoptosis was reversed by both SASP (125.99 ±â€Š8.45% vs. 162.89 ±â€Š11.45%, P = 0.0059) and Sal B (104.27 ±â€Š6.09% vs. 162.89 ±â€Š11.45%, P = 0.0044). High MLCK expression in colitis group was reversed by Sal B (182.44 ±â€Š89.42% vs. 296.23 ±â€Š30.78%, P = 0.0028) but not influenced by SASP (285.23 ±â€Š41.04% vs. 296.23 ±â€Š30.78%, P > 0.05). The recurrence rate induced by recombinant human IL-1ß in Sal B-treated group was significantly lower than that in SASP-treated group. CONCLUSIONS: These results suggested a link between intestinal mucosal barrier dysfunction, especially TJ barrier dysfunction, and colitis recurrence. The TJ barrier dysfunction in remission stage of colitis increased the colitis recurrence. This study might provide potential treatment strategies for IBD recurrence.


Assuntos
Colite , Animais , Benzofuranos , Colite/induzido quimicamente , Colite/tratamento farmacológico , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Interleucina-1beta , Mucosa Intestinal , Camundongos , Camundongos Endogâmicos C57BL , Quinase de Cadeia Leve de Miosina
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