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1.
Brain Sci ; 10(2)2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32033462

RESUMO

Alzheimer's disease (AD) may cause damage to the memory cells permanently, which results in the form of dementia. The diagnosis of Alzheimer's disease at an early stage is a problematic task for researchers. For this, machine learning and deep convolutional neural network (CNN) based approaches are readily available to solve various problems related to brain image data analysis. In clinical research, magnetic resonance imaging (MRI) is used to diagnose AD. For accurate classification of dementia stages, we need highly discriminative features obtained from MRI images. Recently advanced deep CNN-based models successfully proved their accuracy. However, due to a smaller number of image samples available in the datasets, there exist problems of over-fitting hindering the performance of deep learning approaches. In this research, we developed a Siamese convolutional neural network (SCNN) model inspired by VGG-16 (also called Oxford Net) to classify dementia stages. In our approach, we extend the insufficient and imbalanced data by using augmentation approaches. Experiments are performed on a publicly available dataset open access series of imaging studies (OASIS), by using the proposed approach, an excellent test accuracy of 99.05% is achieved for the classification of dementia stages. We compared our model with the state-of-the-art models and discovered that the proposed model outperformed the state-of-the-art models in terms of performance, efficiency, and accuracy.

2.
Chinese Journal of Neurology ; (12): 465-469, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-870832

RESUMO

Parkinson′s disease (PD) is the common progressive neurodegenerative disorder affecting older adults. Alterations of the circadian system occur in PD patients. However, the molecular mechanisms and pathophysiological process remain elusive. Circadian rhythm is modulated by both internal and external factors and using bright light and melatonin as chronotherapeutic tools may be potential therapies to improve symptoms of PD in the future. This article reviewed the abnormal changes of circadian parameters in clinical symptoms of PD and the possible mechanisms of circadian rhythm to provide basis for exploring the therapeutic strategies of circadian rhythm in PD.

3.
Chinese Journal of Surgery ; (12): 928-932, 2018.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-810308

RESUMO

Objective@#To evaluate the clinical value and outcomes of technical improvement of hybrid operatical clipping for large paraclinoid internal carotid artery aneurysms.@*Methods@#A review was conducted on 18 cases of large paraclinoid internal carotid artery aneurysm which were clipped by balloon non-fluoroscopic occlusion of the parent artery via a micro-bone window frontolateral approach in hybrid operating room at Neurosurgery Department of Tianjin Medical University General Hospital from June 2014 to December 2017. There were 8 males and 10 females with age of (63±4) years. There were 6 cases of unruptured aneurysm and 12 cases of ruptured aneurysm of subarachnoid hemorrhage (6 cases of grade Ⅱ, 4 cases of grade Ⅲ and 2 cases of grade Ⅳ in Hunt-Hess classification). Frontolateral approach incision (average length of about 5 cm) and bone window about 3 cm×3 cm were performed. No incision of the neck was needed to expose the internal carotid artery for temporary occlusion. In the operation, the balloon was slowly pushed to the preset position of the internal carotid artery under non-fluoroscopy. The balloon was expanded to block the blood flow of internal carotid artery. Then aneurysm was clipped. The balloon was loosened and retraced to the guiding catheter after clipping. The clipping condition was examined by cerebral angiography. If there was residual aneurysm neck or stenosis of the parent artery, the balloon was pushed under non-fluoroscopy again to temporary occlusion and the clip was adjusted until the aneurysm neck was clamped satisfactorily.@*Results@#Eighteen aneurysms were successfully clipped in hybrid operating room. Fourteen aneurysms showed complete occlusion of the aneurysm neck and no stenosis of the parent artery. Four cases showed residual aneurysm neck after clipping by intraoperative angiography, then aneurysms were clipped satisfy by adjusting the aneurysm clip. The patients were followed up for 3 months to 1 year. Ten patients recovered well (modifed Rankin score (mRS): 0), and 3 patients had no obvious disability (mRS: 1). Two patients with Hunt-Hess grade Ⅲ were slightly disabled (mRS: 2). 1 patients with Hunt-Hess grade Ⅲ were moderately disabled (mRS: 3). 1 patients with Hunt-Hess grade Ⅳ were severely disabled (mRS: 4). One elderly patients with Hunt-Hess grade Ⅳ were seriously disabled (mRS: 5).@*Conclusions@#Application of balloon non-fluoroscopic occlusion clipping for large paraclinoid internal carotid artery aneurysm via a micro-bone window frontolateral approach is safe, effective and minimally invasive.

4.
Chinese Journal of Surgery ; (12): 151-155, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-808141

RESUMO

Objective@#To compare the diagnosis and treatment experience of brain abscesses and improve prognosis.@*Methods@#The data of 302 patients of brain abscess at Department of Neurosurgery in Tianjin Medical University General Hospital from 1980 to 2014 was analyzed retrospectively. There were 215 male and 87 female patients aged from 11 to 82 years with mean age of (30±8) years. The patients was divided into 1980-2001 group and 2002-2014 group according to different diagnosis and the treatment methods. The therapy methods include operation and conservative treatment. There were 196 cases received operation, including 95 cases of excision, 89 cases of ventriculopuncture, 12 cases of excision after ventriculopuncture, 106 cases received drug conservative therapy. Two groups of information including clinical manifestation, abscess location, therapeutic effect and prognosis were compared by χ2 test.@*Results@#Compared to 1980-2001 group, adjacent infection incidence declined(χ2=8.000, P=0.005). The ratio of single abscess declined and multiple abscess increased(χ2=11.060, P=0.001), the infection proportion of frontal lobe and temporal lobe decreased(χ2=9.080, P=0.003; χ2=15.440, P=0.000). The ratio of headache and vomit and papilledema declined significantly(χ2=23.290, P=0.000; χ2=21.020, P=0.000; χ2=2.290, P=0.001). Total mortality of 302 patients were 23 cases and 5 cases of 1980-2001 group and 2002-2014 group (10.4% vs. 6.3%, χ2=1.180, P=0.277). However, there were statistical difference in postoperative mortality between both groups (14.4% vs. 4.0%, χ2 =3.880, P=0.049).@*Conclusion@#With the application of antibiotics and the development of neurosurgical techniques, the prognosis of brain abscess has been improved.

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-606990

RESUMO

BACKGROUND: It has been reported that human adipose-derived mesenchymal stem cells can be induced to differentiate into hepatocyte-like cells with the function of albumin synthesis and urea secretion in vitro.OBJECTIVE: To investigate the potential of adipose-derived mesenchymal stem cells differentiating into hepatocyte-like cells in vitro.METHODS: Adipose-derived mesenchymal stem cells were isolated from the subcutaneous fat of hepatitis B virus infection patients by collagenase digestion and adherent method. Adipose-derived mesenchymal stem cells were induced by three-phase induction method and observed morphologically. The expression levels of alpha-fetoprotein, albumin and cytokeratin 18 were detected by immunohistochemical staining and glycogen synthesis function was detected by glycogen staining method.RESULTS AND CONCLUSION: Most of adipose-derived mesenchymal stem cells induced by three-phase induction method were differentiated into hepatocyte-like cells with polygonal morphology. Immunohistochemistry staining results showed that hepatocyte-like cells expressed alpha-fetoprotein, albumin and cytokeratin 18, and the expression levels of albumin and cytokeratin 18 increased with the culture time. The induced cells had the function of glycogen synthesis and were positive for periodic acid Schiff staining. These results showed that the subcutaneous adipose-derived mesenchymal stem cells could be induced into functional hepatocyte-like cells in hepatitis B virus infection patients.

6.
Chinese Journal of Surgery ; (12): 553-557, 2015.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-308519

RESUMO

The formation mechanisms of rare intracranial aneurysms are various, which lead to various kinds of treatment methods. The present article summarized the pathogenesis, pathologic changes in vascular walls and imaging features of rare intracranial aneurysms including segmental ectasia, aneurysms with dissection, aneurysms with intramural hemorrhage, mycotic aneurysms, aneurysms related to HIV, neoplastic aneurysms and traumatic aneurysms through literature review.


Assuntos
Humanos , Diagnóstico por Imagem , Dilatação Patológica , Aneurisma Intracraniano , Diagnóstico , Patologia , Terapêutica
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-402599

RESUMO

BACKGROUND:In recent years,it has been shown in studies that regulation of the expression of Has1 is very important to maintain neural stem cells and regulate its differentiation during the development of embryonic nervous system.Moreover,upregulation of Hes1 expression is required for quiescent adult flbroblasts resuming proliferation.This indicates that there is a close relationship between Hes1 and some potential stem cells in adult.Therefore,the study of Hes1 expression in neural stem cells and its relationship with adult neurogenasis is put on the agenda.However,the expression of Hes1 in adult brain is still not clear.OBJECTIVE:To observe the expression of Hea1 in adult mouse brain and the cell types of Has1 positive cells.METHODS:Totally 12 adult male C57BL/6 mice were randomly evenly divided into two groups by using the random number table.For the first group,the mouse brain was removed directly and immunohistochemical staining was used to detect the expression of Has1 in the adult mouse brain.For the second group,Brdu was injected intraperitoneally to every mouse with a dosage of 200 mg/kg,once a day,for 3 days.The mouse brain was removed at 4 days and then double staining was carded out to observe and analysis the cell types of Hes1 positive cells in hippocampus.RESULTS AND CONCLUSION:Hes1 was expressed in all the observed anatomical site where neural cells exist,Brdu positive cells nearly all expressed Hea1,NeuN positive cells all expressed Has1,whereas GFAP positive cells did not express Hes1 completely.Hes1 was expressed in all neurons and neural stem cells,and glial cells did not express Hes1.

8.
Chinese Journal of Surgery ; (12): 702-704, 2002.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-264779

RESUMO

<p><b>OBJECTIVE</b>To observe the expression of bcl-2 and bcl-xL in rat brain neuron after acute brain trauma.</p><p><b>METHODS</b>The rat model of mild and sever brain trauma were made by diffused brain injury. The expression of bcl-2 and bcl-xL in rat brain neuron was examined by immunohistochemical staining. Rat neuron apoptosis was detected by TUNEL method.</p><p><b>RESULTS</b>There were few bcl-2 (cortex: 4.40 +/- 1.67, hippocampal: 3.20 +/- 1.30) and lots of bcl-xL (cortex: 45.60 +/- 4.34, hippocampal: 50.20 +/- 3.50) expression in normal controls. After impact, the expression of bcl-2 in rat brain neuron increased, most distinctly on day 1(cortex: 30.0 +/- 4.3, hippocampal: 46.6 +/- 3.2), in mild group. A negative correlation was seen between bcl-2 expression and neuronal apoptosis (-1 < r < -0.847, P< 0.01, n = 10). No change was seen in bcl-xL expression.</p><p><b>CONCLUSIONS</b>bcl-2 expression increased after acute brain trauma but bcl-xL did not change much. Both bcl-2 and bcl-xL are concerned with anti-apoptosis in neuron after acute brain trauma.</p>


Assuntos
Animais , Masculino , Ratos , Doença Aguda , Apoptose , Lesões Encefálicas , Metabolismo , Patologia , Imuno-Histoquímica , Neurônios , Química , Patologia , Proteínas Proto-Oncogênicas c-bcl-2 , Ratos Wistar , Proteína bcl-X
9.
Chinese Journal of Traumatology ; (6): 250-253, 2002.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-332957

RESUMO

<p><b>OBJECTIVE</b>To analyze the role of Caspase 3 in neuronal apoptosis after acute brain injury.</p><p><b>METHODS</b>Experiments were carried out with rat diffuse brain trauma model. The neuronal DNA injury in cortex and hippocampus was observed by TUNEL stain. The mRNA and protein expressions and enzyme activation of Caspase 3 were observed by Northern blot, in situ hybridization, immunohistochemistry stain and Western blot, respectively. Special Caspase 3 enzyme inhibitor was used to observe the therapeutic effect.</p><p><b>RESULTS</b>TUNEL positive neurons appeared 2 hours after severe trauma, peaked at 1 day and lasted for 7 days. Northern blot showed that the Caspase 3 mRNA expression was increased and peaked at 1 day, about twice higher than the control. In the area of cortex and hippocampus, positive mRNA staining neurons appeared most distinct on one day. With the antibody for Caspase 3 P20 subunit, the active Caspase 3 expression peaked at 1-3 days. The electrophoresis band of PARP degradation would be seen by Western blot. Caspase 3 enzyme inhibitor could reduce apoptotic neuronal death without any effect on Caspase 3 P20 subunit expression.</p><p><b>CONCLUSIONS</b>After brain trauma, Caspase 3 mRNA and protein expressions and enzyme activation are enhanced in combination with neuronal apoptosis. Special Caspase 3 enzyme inhibitor can apparently decrease the neuronal apoptosis.</p>


Assuntos
Animais , Ratos , Doença Aguda , Apoptose , Fisiologia , Lesões Encefálicas , Caspase 3 , Caspases , Metabolismo , Ativação Enzimática , Inibidores Enzimáticos , Farmacologia , Sistema Nervoso , Neurônios , Fisiologia , RNA Mensageiro , Metabolismo , Ratos Wistar
10.
Chinese Journal of Traumatology ; (6): 131-135, 2000.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-268523

RESUMO

OBJECTIVE: To investigate the relation betwe en necrosis and apoptosis in the hippocampus of exogenous bFGF on this process. METHODS: With Marmarou's method we produced a severe diffuse brain injury and studied the changes in the hippocampus by adapting a modified T dT-mediated dUTP-biotin nick end labeling (TUNEL) method. At the same time we observed the effect of exogenous bFGF on neuronal necrosis and apoptosis. RESULTS: We found that together with cell necrosis there was an increase in the number of apoptotic neurons in the hippocampus CA2-3 sectors a s early as 4 h after injury, with numbers reaching a maximum at 7 d. Exogenous b FGF resulted in a definite reduction in the amount of necrosis and apoptosis. CONCLUSIONS: Neuronal necrosis and apoptosis occur in combinati on after brain injury and that one of the causes may be the insufficience expres sion of the bFGF gene in the hippocampus after severe injury. Exogenous bFGF and similar substance may prove clinically useful after brain injury by reducing ce ll necrosis and apoptosis.

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