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1.
Protein & Cell ; (12): 105-122, 2023.
Article in English | WPRIM | ID: wpr-971612

ABSTRACT

Glioblastoma multiforme (GBM), a highly malignant and heterogeneous brain tumor, contains various types of tumor and non-tumor cells. Whether GBM cells can trans-differentiate into non-neural cell types, including mural cells or endothelial cells (ECs), to support tumor growth and invasion remains controversial. Here we generated two genetic GBM models de novo in immunocompetent mouse brains, mimicking essential pathological and molecular features of human GBMs. Lineage-tracing and transplantation studies demonstrated that, although blood vessels in GBM brains underwent drastic remodeling, evidence of trans-differentiation of GBM cells into vascular cells was barely detected. Intriguingly, GBM cells could promiscuously express markers for mural cells during gliomagenesis. Furthermore, single-cell RNA sequencing showed that patterns of copy number variations (CNVs) of mural cells and ECs were distinct from those of GBM cells, indicating discrete origins of GBM cells and vascular components. Importantly, single-cell CNV analysis of human GBM specimens also suggested that GBM cells and vascular cells are likely separate lineages. Rather than expansion owing to trans-differentiation, vascular cell expanded by proliferation during tumorigenesis. Therefore, cross-lineage trans-differentiation of GBM cells is very unlikely to occur during gliomagenesis. Our findings advance understanding of cell lineage dynamics during gliomagenesis, and have implications for targeted treatment of GBMs.


Subject(s)
Mice , Animals , Humans , Glioblastoma/pathology , Endothelial Cells/pathology , DNA Copy Number Variations , Brain/metabolism , Brain Neoplasms/pathology
2.
Journal of Biomedical Engineering ; (6): 409-417, 2023.
Article in Chinese | WPRIM | ID: wpr-981557

ABSTRACT

High-frequency steady-state asymmetric visual evoked potential (SSaVEP) provides a new paradigm for designing comfortable and practical brain-computer interface (BCI) systems. However, due to the weak amplitude and strong noise of high-frequency signals, it is of great significance to study how to enhance their signal features. In this study, a 30 Hz high-frequency visual stimulus was used, and the peripheral visual field was equally divided into eight annular sectors. Eight kinds of annular sector pairs were selected based on the mapping relationship of visual space onto the primary visual cortex (V1), and three phases (in-phase[0º, 0º], anti-phase [0º, 180º], and anti-phase [180º, 0º]) were designed for each annular sector pair to explore response intensity and signal-to-noise ratio under phase modulation. A total of 8 healthy subjects were recruited in the experiment. The results showed that three annular sector pairs exhibited significant differences in SSaVEP features under phase modulation at 30 Hz high-frequency stimulation. And the spatial feature analysis showed that the two types of features of the annular sector pair in the lower visual field were significantly higher than those in the upper visual field. This study further used the filter bank and ensemble task-related component analysis to calculate the classification accuracy of annular sector pairs under three-phase modulations, and the average accuracy was up to 91.5%, which proved that the phase-modulated SSaVEP features could be used to encode high- frequency SSaVEP. In summary, the results of this study provide new ideas for enhancing the features of high-frequency SSaVEP signals and expanding the instruction set of the traditional steady state visual evoked potential paradigm.


Subject(s)
Humans , Evoked Potentials, Visual , Brain-Computer Interfaces , Healthy Volunteers , Signal-To-Noise Ratio
3.
Journal of Biomedical Engineering ; (6): 995-1002, 2021.
Article in Chinese | WPRIM | ID: wpr-921838

ABSTRACT

Motor imagery (MI), motion intention of the specific body without actual movements, has attracted wide attention in fields as neuroscience. Classification algorithms for motor imagery electroencephalogram (MI-EEG) signals are able to distinguish different MI tasks based on the physiological information contained by the EEG signals, especially the features extracted from them. In recent years, there have been some new advances in classification algorithms for MI-EEG signals in terms of classifiers versus machine learning strategies. In terms of classifiers, traditional machine learning classifiers have been improved by some researchers, deep learning and Riemannian geometry classifiers have been widely applied as well. In terms of machine learning strategies, ensemble learning, adaptive learning, and transfer learning strategies have been utilized to improve classification accuracies or reach other targets. This paper reviewed the progress of classification algorithms for MI-EEG signals, summarized and evaluated the existing classifiers and machine learning strategies, to provide new ideas for developing classification algorithms with higher performance.


Subject(s)
Algorithms , Brain-Computer Interfaces , Electroencephalography , Imagery, Psychotherapy , Imagination , Machine Learning
4.
Journal of Interventional Radiology ; (12): 673-675, 2017.
Article in Chinese | WPRIM | ID: wpr-614823

ABSTRACT

At present,peripherally inserted central catheter (PICC) and totally implantable access port (TIAP) are most commonly used for the medium-term and long-term ccntral vcnous infusion in China,which is mainly adopted for long-term repeated chemotherapy,nutritional support and other clinical treatments.As an advanced infusion route,this technique needs to be further popularized in clinical practice to benifit the majority of patients.However,in aspect of the implantation,use,maintenance,and the diagnosis and treatment of complications of long-term central venous access,there are still a lot of problems,to which sufficient attention should be paid.Standard implantation and maintenance are of great importance for the safe implantation of central venous access and long-term safe use.This paper aims to make a comprehensive review concerning the problems of long-term indwelling of central venous access,the basic solutions,and the whole course management of central venous access.In order to promote the technique of central venous access to continually develop,the multidisciplinary collaborative team with tacit cooperation,standardized system and regulatory process should be emphasized.

5.
China Oncology ; (12): 276-280, 2017.
Article in Chinese | WPRIM | ID: wpr-512520

ABSTRACT

Background and purpose: Current colorectal cancer patient-derived xenografts (PDXs) models were established by samples taken during surgery. However, metastatic colorectal cancer (mCRC) patients have less surgical opportunities, and it was difcult to obtain enough tumor fragment. The aim of the present study was to es-tablish mCRC PDXs by image-guided biopsy. Methods: A total of 12 patients with colorectal cancer who underwent surgery were included. All patients had recurrent lesions or metastatic lesions needed to be histologically confirmed, and none of them had contraindication to biopsy. Tumor tissues not required for clinical diagnosis were used to establish mCRC PDXs. Results: Seven PDXs grew sufficiently for transfer into mice. The success rate was 77.8%. Conclusion:The PDXs established by image-guided biopsy had the advantage of convenient operation, good reproducibility, high achievement ratio, short experimental periodicity and reliably retain specific genetic and morphological features of the primary patient tumors.

6.
China Oncology ; (12): 257-262, 2016.
Article in Chinese | WPRIM | ID: wpr-490126

ABSTRACT

Background and purpose:Early evaluating the therapeutic efficacy of transcatheter arterial chemoembolization (TACE) in patients with hepatic cancer is still a diffcult clinical problem. The purpose of this study was to evaluate the ability of the apparent diffusion coeffcient (ADC) to help predict early disease progression after TACE.Methods:Institutional review board approval was obtained, and all patients signed informed consent. Magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) (b=50, 500, 1 000 mm2/s) were performed before and 1 month after initiating TACE for 23 patients with hepatic cancer (14 were male, 9 were female; mean age: 53.3 years;range: 21-85 years). Contrast-enhanced MRI was performed 3 months after initiating TACE. Patients were classiifed as either progressing or non-progressing according to RECIST 1.1. The preoperative ADC values of tumor and the ADC values of tumor 1 month after TACE were analyzed by pairedt-test in both progressing and non-progressing group. Unpairedt-test was used to compare ADC parameters between progressing and non-progressing group. In all the 23 hepatic cancer patients, receiver operating characteristic (ROC) curve analysis was performed to determine a threshold ADC ratio (ADC%) to differentiate progressing from non-progressing patients.Results:Thirteen progressing and 9 non-progressing patients were evaluated. Increase in ADCs of tumor was observed in non-progressing patients at 1 month after TACE compared with preoperative ADCs. There was a signiifcant difference between the 2 groups (P=0.01). In progressing group, preoperative ADCs of tumor were similar to those at 1 month after TACE (P=0.221). There was no significant difference in preoperative ADCs of tumor and ADC% between the progressing and non-progressing groups. In patients with hepatic cancer, 1 month ADC ratio in non-progressing patients were signiifcantly higher than those of progressing patients (P=0.029). Using ROC to evaluate the ability of ADC% could predict early disease pro-gression after TACE. Using -6.455% as the threshold, the area under the ROC curve was 0.867 (95%CI: 0.643-1.000). The sensitivity was 100%, and the speciifcity was 66.7%.Conclusion:One month after TACE, the increases in ADCs of tumor were observed only in the non-progressing group; and the ADC ratio seems to be a promising tool for helping predict the early disease progression after TACE in patients with hepatic cancer.

7.
China Oncology ; (12): 199-204, 2015.
Article in Chinese | WPRIM | ID: wpr-465450

ABSTRACT

Background and purpose: With characteristic but non-specific features, subsolid pulmonary nodules (SSPN) is closely associated with early lung cancer. This study aimed to estimate the imaging value of SSPN in stageⅠA lung cancer, and summarized the radiological features of various SSPNs, retrospectively. Methods:The clinical data and imaging data of 405 patients with solitary pulmonary nodules (SPNs) from Apr. 2008 to Apr. 2014 at Fudan University Shanghai Cancer Center were collected. According to ground-glass opacity (GGO) proportion, SPNs were divided into 3 groups:pure ground-glass opacity (pGGO), mixed ground-glass opacity (mGGO) and solid nodule (SN). The malignant ratios were calculated based on the postoperatively pathological results. Besides, SSPNs were classiifed into stageⅠA lung cancer group and benign lesions group aiming at identifying the differentiating computed tomography (CT) features. Results:Of the enrolled 405 SPN patients, there were 367 SSPNs (including 124 pGGOs and 243 mGGOs) whose incidence in stageⅠA lung cancer group was signiifcantly higher than those in benign group [95.9%(257/268) vs 80.3%(110/137), P<0.001]. The total malignant ratio of SSPN was 70.0%(257/367), mGGO had a higher malignant ratio (72.0%) than those of pGGO (66.1%) and SN (28.9%). The malignant SSPNs were frequently detected in upper lobe of middle-aged women with a higher incidence of irregular edge, spiculation, lobulation and pleural retraction than benign group (P<0.05). Conclusion:SSPN is one of the signiifcantly malignant indicators, and mGGO has the highest malignant tendency. Senility, female, irregular edge, spiculation, lobulation, pleural retraction and pulmonary upper lobe distribution are demonstrated the signiifcant discriminators from benign lesions.

8.
China Oncology ; (12): 311-315, 2015.
Article in Chinese | WPRIM | ID: wpr-463403

ABSTRACT

Transcatheter arterial chemoembolization (TACE) is the main treatment method for advanced hepatocellular carcinoma (HCC). As a non-invasive functional MR imaging, diffusion weighted imaging (DWI) can relfect the functional changes in tumor before morphologic changes. In the follow-up of HCC after TACE, DWI can detect new lesions and distinguish necrotic neoplastic tissue and residual neoplastic tissue timely and accurately.

9.
China Oncology ; (12): 347-352, 2013.
Article in Chinese | WPRIM | ID: wpr-433465

ABSTRACT

10.3969/j.issn.1007-3969.2013.05.005

10.
Chinese Journal of Radiology ; (12): 518-522, 2010.
Article in Chinese | WPRIM | ID: wpr-389567

ABSTRACT

Objective To evaluate the feasibility,safety and clinical value of CT-guided localization with a Hook-wire system for nodular pulmonary lesions before video-assisted thoracoscopic resection (VATS). Methods The records of all patients undergoing VATS resection for solitary pulmonary nodules preoperatively localized by CT-guided a Hook-wire system were assessed with respect to failure to localize the lesion by the Hook-wire system, conversion thoracotomy rate, duration of operation, postoperative complications, and histology of nodular pulmonary lesions. Results Sixty-eight patients with seventy four nodules underwent VATS resections. Preoperative CT-guided Hook-wire localization succeeded in all patients ( 100. 0% ). Conversion thoracotomy was necessary in 2 patients. The average operative time was ( 15 ±6)min. Asymptomatic complication rate was 70.6% (48/68), asymptomatic pneumothorax rate, asymptomatic hemorrhage rate and simultaneous pneumothorax and bleeding rate were 45.6% (31/68),25.0% ( 17/68 ) and 4. 4% ( 3/68 ), respectively. The mean hospitalization was ( 15 ± 6 ) days.Histological assessment revealed primary lung cancer (NSCLC) in 30, metastasis in 18, and nonmalignant disease in 26 nodules. Conclusions Video-assisted thoracoscopic resection of nodular pulmonary lesions previously localized by a CT-guided Hook-wire system is related to a low conversion thoracotomy rate, short operation time, and high safety. It for differential diagnosis and treatment.

11.
China Oncology ; (12): 797-801, 2009.
Article in Chinese | WPRIM | ID: wpr-405625

ABSTRACT

Venous thromboembolism (VTE) and pulmonary embolism(PE) contributes to morbidity and mortality in cancer patients and is a frequent complication of anticancer therapy. Precautions and managements are needed to decrease the morbidity due to VTE and PE. There is no standard procedure for the treatment of the complications. Interventional radiology has been shown to play an important role in the treatment of various diseases. Recently, interventional radiology has developed in the treatment of VTE and PE. This review is to summarize the status of VTE and PE in patients with malignant tumors and their treatment by interventional radiology therapy.

12.
Journal of Interventional Radiology ; (12)2001.
Article in Chinese | WPRIM | ID: wpr-581153

ABSTRACT

The purpose of intra-arterial perfusion chemotherapy for locally advanced and recurrent breast cancer is to gain the chance of operative excision and to control the clinical symptoms.Intra-arterial perfusion chemotherapy has been widely employed in clinical practice and has already achieved satisfactory therapeutic results.Based on the medical documents concerning the interventional therapy of breast cancer,which have been published both at home and abroad,the authors attempt to make some suggestions in order to standardize the clinical application of this interventional technique.This paper will focus on the blood supply and imaging findings of the breast cancer,as well as on the preoperative preparation,indications and contraindications,medication,complications and therapeutic efficacy of intra-arterial perfusion chemotherapy.

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