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1.
Ther Adv Neurol Disord ; 12: 1756286419844113, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31105769

RESUMO

Cerebral amyloid angiopathy (CAA) is a cerebral small vessel disease caused by ß -amyloid (Aß) deposition at the leptomeningeal vessel walls. It is a common cause of spontaneous intracerebral hemorrhage and a frequent comorbidity in Alzheimer's disease. The high recurrent hemorrhage rate in CAA makes it very important to recognize this disease to avoid potential harmful medication. Imaging studies play an important role in diagnosis and research of CAA. Conventional computed tomography and magnetic resonance imaging (MRI) methods reveal anatomical alterations, and remains as the most reliable tool in identifying CAA according to modified Boston criteria. The vascular injuries of CAA result in both hemorrhagic and ischemic manifestations and related structural changes on MRI, including cerebral microbleeds, cortical superficial siderosis, white matter hyperintensity, MRI-visible perivascular spaces, and cortical microinfarcts. As imaging techniques advance, not only does the resolution of conventional imaging improve, but novel skills in functional and molecular imaging studies also enable in vivo analysis of vessel physiological changes and underlying pathology. These modern tools help in early detection of CAA and may potentially serve as sensitive outcome markers in future clinical trials. In this article, we reviewed past studies of CAA focusing on utilization of various conventional and novel imaging techniques in both research and clinical aspects.

2.
Magn Reson Med ; 82(2): 763-774, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30957300

RESUMO

PURPOSE: The purpose of this study was to investigate the feasibility of in vivo imaging of human pancreatic ductal cells by OATP1B3 reporter gene under MRI. METHODS: A human cell line (PANC-1) derived from the pancreatic ductal epithelium was used in this study. After transduction of OATP1B3, the cellular physiological functions and the ability of intracellular uptake of the MRI contrast medium (Gd-EOB-DTPA) were examined. Induced differentiation of the PANC-1 cells into hormone-secreting cells were performed to simulate pancreatic ß-like cells. The hormone-secreting cells were implanted into rats and in vivo MRI was evaluated. RESULTS: The mRNA and proteins of OATP1B3 were highly expressed. No significant change of cellular physiological functions was found after the expression. After induced differentiation, the hormone secretion capacities of the OATP1B3-expressing PANC-1 cells were confirmed. Intra-cellular uptake of Gd-EOB-DTPA was determined in vitro by inductively coupled plasma mass spectrometry and MRI. In vivo MRI of the OATP1B3-expressing xenograft revealed an increased signal intensity after contrast enhancement. CONCLUSION: OATP1B3 can be used as a safe and feasible in vivo MRI gene reporter for human pancreatic ductal cells.

3.
Clin EEG Neurosci ; 50(4): 227-230, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30862179

RESUMO

Building on the knowledge of sex differences in auditory sensory gating in schizophrenia and hippocampal involvement in sensory gating, this study aimed to investigate sex as a potential moderator of the association between hippocampal volume and P50 in schizophrenia. Auditory P50 gating and hippocampal volume were measured in 16 male and 15 female patients with schizophrenia. The correlations between hippocampal volume and P50 were analyzed in males and females separately, corrected for potential confounders, including age, duration of illness, and antipsychotic medication. Different associative patterns of hippocampal volume with P50 gating ratio and with P50 difference were found by sex. The results suggest sex may play a role in the physiology of sensory gating.


Assuntos
Hipocampo/patologia , Hipocampo/fisiopatologia , Esquizofrenia/patologia , Esquizofrenia/fisiopatologia , Filtro Sensorial/fisiologia , Caracteres Sexuais , Estimulação Acústica , Adulto , Percepção Auditiva/fisiologia , Potenciais Evocados , Potenciais Evocados Auditivos , Feminino , Humanos , Masculino , Psicologia do Esquizofrênico
4.
Conf Proc IEEE Eng Med Biol Soc ; 2019: 1035-1038, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946070

RESUMO

Inspired by the outstanding performance of deep convolutional neural networks (CNNs), nowadays modern computer-aided detection (CAD) systems for CT lung nodules generally delve into 2D or 3D CNNs directly without considering traditional image preprocessing techniques. However, detection of large pulmonary nodules and masses are computationally challenging, especially for 3D CNNs. In this paper, we examine the possibility of using volume visualized CT thin-slab images with 2D CNNs to reduce computation complexity and improve CAD performance. We tested 4 types of images: original 2D CT, 2D projection of thin slabs, mixture by arranging original and projection in different color channels, and mixture by the pixelwise maximum intensity of original CT and projection. We evaluated these images on a dataset of 30 CT scans with 30 different-sized nodules and masses on GoogLeNet via a transfer learning and cross validation paradigm. We found that projection visualization alone had a better or equal area-under curve score for all the different-sized nodules and masses. However, mixture by the maximum of CT and projection demonstrated a preferred performance with a true positive rate of 0.8 and a false positive rate of 0.046 in detecting large nodules and masses.

5.
J Neurosurg Pediatr ; 22(6): 663-671, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30168733

RESUMO

OBJECTIVEPediatric and adult patients with moyamoya disease experience similar clinical benefits from indirect revascularization surgeries, but there are still debates about age-related angiographic differences of the collaterals established after surgery. The goal of this study was to assess age-related differences on ultrasonography before and after indirect revascularization surgeries in moyamoya patients, focusing on some ultrasonographic parameters known to be correlated with the collaterals supplied by the external carotid artery (ECA).METHODSThe authors prospectively included moyamoya patients (50 and 26 hemispheres in pediatric and adult patients, respectively) who would undergo indirect revascularization surgery. Before surgery and at 1, 3, and 6 months after surgery, the patients underwent ultrasonographic examinations. The ultrasonographic parameters included peak-systolic velocity (PSV), end-diastolic velocity (EDV), resistance index (RI), and flow volume (FV) measured in the ECA, superficial temporal artery (STA), and internal carotid artery on the operated side. The mean values, absolute changes, and percentage changes of these parameters were compared between the pediatric and adult patients. Logistic regression analysis was used to clarify the determinants affecting postoperative EDV changes in the STA.RESULTSBefore surgery, the adult patients had mean higher EDV and lower RI in the STA and ECA than the pediatric group (all p < 0.05). After surgery, the pediatric patients had greater changes (absolute and percentage changes) in the PSV, EDV, RI, and FV in the STA and ECA (all p < 0.05). The factors affecting postoperative EDV changes in the STA at 6 months were age (p = 0.006) and size of the revascularization area (i.e., revascularization in more than the temporal region vs within the temporal region; p = 0.009). Pediatric patients who received revascularization procedures in more than the temporal region had higher velocities (PSV and EDV) in the STA than those who received revascularization within the temporal region (p < 0.05 at 1-6 months), but such differences were not observed in the adult group.CONCLUSIONSThe greater changes of these parameters in the STA and ECA in pediatric patients than in adults after indirect revascularization surgeries indicated that pediatric patients might have a greater increase of collaterals postoperatively than adults. Pediatric patients who undergo revascularization in more than the temporal region might have more collaterals than those who undergo revascularization within the temporal region.


Assuntos
Encéfalo/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Revascularização Cerebral/métodos , Doença de Moyamoya/diagnóstico por imagem , Adolescente , Adulto , Fatores Etários , Encéfalo/cirurgia , Artéria Carótida Interna/cirurgia , Angiografia Cerebral , Criança , Feminino , Humanos , Masculino , Doença de Moyamoya/cirurgia , Período Pós-Operatório , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia Doppler em Cores
6.
Clin Neurophysiol ; 129(9): 1899-1906, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30005217

RESUMO

OBJECTIVE: This study aimed to investigate the association between mismatch negativity (MMN) and volumes of several brain regions measured using a semi-automated method in patients with schizophrenia and healthy controls. METHODS: MMN in response to duration deviants and magnetic resonance imaging were acquired from 36 schizophrenia patients and 14 healthy controls. FreeSurfer was used for volumetric analysis. MMN amplitudes, brain volumes and their association were compared between schizophrenia and controls. Correlation analysis and multiple linear regression analysis were used to examine the correlated variables of MMN. RESULTS: MMN amplitude was significantly lower in the schizophrenia group. In schizophrenia, MMN was positively correlated with age and negatively correlated with left hippocampal and right pars opercularis volumes. The association between left hippocampal volume and MMN in schizophrenia remained significant after controlling for potential confounders. CONCLUSIONS: Smaller hippocampal volume may play a role in the abnormal manifestation of MMN in schizophrenia. SIGNIFICANCE: The significant association between MMN and left hippocampal volume may suggest unique neurobiological contribution of hippocampus in auditory processing in schizophrenia.


Assuntos
Encéfalo/fisiopatologia , Potenciais Evocados/fisiologia , Esquizofrenia/fisiopatologia , Estimulação Acústica , Adulto , Encéfalo/diagnóstico por imagem , Eletroencefalografia , Potenciais Evocados Auditivos/fisiologia , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/fisiopatologia , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão/fisiologia , Esquizofrenia/diagnóstico por imagem , Adulto Jovem
7.
World Neurosurg ; 119: e180-e191, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30031192

RESUMO

BACKGROUND: Indirect revascularization is simple and safe, but it is not commonly used in adult moyamoya disease owing to its unreliable effect. This prospective study aimed to evaluate the effectiveness of indirect revascularization in treating adult moyamoya disease after refinement of the surgical technique and perioperative care. METHODS: Adult patients who underwent indirect revascularization as the primary treatment for moyamoya disease between November 2013 and January 2017 were studied. The indirect revascularization procedures included encephalo-duro-arterio-synangiosis and encephalo-myo-synangiosis in the temporal region and encephalo-pericranio-synangiosis in other hypoperfusion areas. The preoperative and postoperative clinical conditions, cerebral angiography findings, and time-to-peak prolongation areas on magnetic resonance perfusion studies were assessed to evaluate the revascularization effect. Refinements of the surgical technique included the selection of surgical area based on perfusion imaging, craniotomy size, and number of affected hemispheres, along with the inclusion of a dural flap in every procedure. RESULTS: Nineteen patients (17 females and 2 males), and a total of 31 cerebral hemispheres, were included. The mean patient age was 32.7 ± 11.4 years. After a mean follow-up of 38.6 ± 11.5 months, all patients showed clinical improvement or stabilization. Available postoperative angiography demonstrated Matsushima grade A or B in 19 of 21 hemispheres. The mean time-to-peak prolongation index of all 31 hemispheres improved from 24.09 ± 9.83% preoperatively to 12.82 ± 6.75% at 3-6 months after surgery (P < 0.001). The complication rate was 12.9%, and all complications were transient. CONCLUSIONS: With refinements of surgical techniques and perioperative care, indirect revascularization is more reliable and can be a viable alternative treatment for adult moyamoya disease. In our cohort, outcomes were satisfactory, with mean 38.6-month follow-up.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Revascularização Cerebral/métodos , Craniotomia/métodos , Angiografia por Ressonância Magnética/métodos , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Adulto , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
8.
J Neurointerv Surg ; 10(11): 1114-1119, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29459366

RESUMO

BACKGROUND AND PURPOSE: Engorged medullary vein (EMV) in patients with intracranial dural arteriovenous fistula (DAVF) suggests venous congestion. The aim of this study is to investigate its prevalence, pattern, and correlation with clinical findings. MATERIALS AND METHODS: CT angiography (CTA) raw data of DAVF were used for multiplanar reconstruction and then analyzed for the presence and pattern of EMV, which is defined as a dilated vein in the cerebral white matter. Patients with EMV were divided into two groups: regional and extensive. Regional type is defined as EMV limited to one cerebral hemisphere or cerebellum without evidence of subcortical calcification. Extensive type is defined as EMV involvement of more than one cerebral hemisphere or both the cerebrum and cerebellum. Descriptive analysis of clinical information, DAVF characteristics, and other imaging findings was conducted. Clinical information, including demographic data, clinical presentation, and hemorrhage, were correlated with both types of EMV. RESULTS: Among 192 eligible patients with DAVF, 71 (37%) had EMV. Patients with EMV were older (63 years vs 56 years, P=0.02), with DAVF more often at the transverse and sigmoid sinus (P<0.001), and more often presented with aggressive symptoms (59% vs 34%, P=0.02) than non-EMV patients, but there was no difference in the presentation of hemorrhage (15% vs 16%, P=0.99). Patients with regional EMV had a higher proportion of hemorrhage than those with the extensive type (24% vs 0%, P=0.006). CONCLUSIONS: EMV in patients with DAVF is associated with an aggressive manifestation. Regional type EMV is associated with a higher risk of a hemorrhagic presentation.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Malformações Vasculares do Sistema Nervoso Central/epidemiologia , Angiografia Cerebral/métodos , Angiografia por Tomografia Computadorizada/métodos , Bulbo/irrigação sanguínea , Bulbo/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Malformações Vasculares do Sistema Nervoso Central/cirurgia , Estudos Transversais , Feminino , Humanos , Masculino , Bulbo/cirurgia , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos
9.
J Formos Med Assoc ; 117(9): 806-813, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29097075

RESUMO

BACKGROUND/PURPOSE: Endovascular thrombectomy has been strongly recommended for treatment of acute ischemic stroke (AIS) with large vessel occlusion. This study aimed to evaluate its efficacy and safety in an Asian population from a single center in Taiwan. METHODS: Patients who experienced AIS and received endovascular thrombectomy during the period of September 2014 to September 2016 at National Taiwan University Hospital were included. Factors related to favorable outcome, defined as modified Rankin scale 0-2 at 90 days after stroke, were analyzed. RESULTS: During the study period, 65 patients (mean age, 71.9 ± 12.4 years; 44.6% females) received endovascular thrombectomy, including 33 who received intravenous thrombolysis before the endovascular treatment. A significant trend of increasing thrombectomy therapy was observed. The median National Institutes of Health Stroke Scale (NIHSS) score on admission was 19 (interquartile range, 15-26). The sites of vessel occlusion were middle cerebral artery in 47 (72.3%) patients, intracranial internal carotid artery in 8 (12.4%), anterior cerebral artery in 1 (1.5%), and basilar artery in 9 (13.8%). The median times from stroke onset to groin puncture and from groin puncture to recanalization time were 200 and 29.5 min, respectively. Successful revascularization was achieved in 41 (63.1%) patients. Two (3.1%) patients had symptomatic hemorrhagic transformation. At 90 days, 25 (38.5%) patients achieved favorable outcome. A shorter time from onset to puncture, and successful recanalization were independent predictors of favorable outcome. CONCLUSION: This study demonstrated the therapeutic promise of endovascular thrombectomy for treatment of AIS with large vessel occlusion in a clinical setting.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/terapia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Trombectomia , Idoso , Idoso de 80 Anos ou mais , Artéria Carótida Interna/fisiopatologia , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Índice de Gravidade de Doença , Taiwan , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
10.
Neuroradiology ; 60(1): 7-15, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29188304

RESUMO

PURPOSE: Computed tomography angiography (CTA) and magnetic resonance imaging/angiography (MRI/MRA) are used for the diagnosis of intracranial dural arteriovenous fistulas (DAVFs). The purpose of this study was to compare the diagnostic accuracy of CTA and magnetic resonance imaging/angiography (MRI/MRA) for detection of cortical venous reflux (CVR) in intracranial DAVFs. METHODS: The records of patients with angiography-confirmed intracranial DAVFs who also received CTA and MRI/MRA from January 2008 to July 2016 were reviewed. CTA and MRI/MRA were reviewed for signs of CVR, and the diagnostic accuracy of individual signs was evaluated by receiver operating curve (ROC) analysis. RESULTS: A total 108 patients were included in this study. CTA signs of CVR included abnormal dilatation, early enhancement, and the presence of a medullary or pial vein. MRI/MRA signs of CVR included abnormal dilatation, early enhancement, flow-related enhancement, flow void, and medullary or pial venous collaterals. The sensitivity of individual CTA signs ranged from 62 to 96%, and specificities from 79 to 94%. The sensitivities of individual MRI/MRA signs ranged from 58 to 83%, and specificities from 77 to 93%. The area under ROC curve (AUC) of CTA and MRI/MRA were 0.91 and 0.87, respectively (P = 0.04 in direct comparison). In subgroup analysis, CTA had better diagnostic accuracy for higher grade disease (P = 0.05) and non-aggressive manifestation (P = 0.04). CONCLUSIONS: Both CTA and MRI/MRA have good diagnostic accuracy for detection of CVR in patients with intracranial DAVFs. There is modest evidence that CTA is better than MRI/MRA.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Angiografia Cerebral , Angiografia por Tomografia Computadorizada , Angiografia por Ressonância Magnética , Imagem por Ressonância Magnética , Adulto , Idoso , Meios de Contraste , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
11.
FASEB J ; 32(3): 1705-1715, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29146731

RESUMO

Reporter proteins have broad applications in visualizing molecular events at the cellular, tissue and whole-body levels. Transmembrane transporters recognizing specific molecular domains are of particular interest because they enable the migration of signal-source molecules from the extracellular space to the cytoplasm for subsequent application in multimodality imaging. Organic anion-transporting polypeptides (OATPs) have demonstrated their MRI reporter efficacy. We further expanded their use as a dual-modality reporter in MRI and noninvasive in vivo imaging system (IVIS). We overexpressed OATP1B3 in the HT-1080 sarcoma cell line. Both Gd-EOB-DTPA, an MRI contrast agent, and indocyanine green (ICG), a near-infrared fluorescent dye that provides better deep-tissue detection because of its long wavelength, could be delivered to the intracellular space and imaged in a tumor-bearing nude mouse model. Our in vivo dual-imaging reporter system achieved high sensitivity in MRI and observation periods lasting as long as 96 h in IVIS. Because of the superior temporal and spatial resolutions and the clinical availability of both ICG and Gd-EOB-DTPA, this dual-imaging OATP1B3 system will find biomedical use in tumor biology, stem cell trafficking, and tissue engineering.-Wu, M.-R., Liu, H.-M., Lu, C.-W., Shen, W.-H., Lin, I.-J., Liao, L.-W., Huang, Y.-Y., Shieh, M.-J., Hsiao, J.-K. Organic anion-transporting polypeptide 1B3 as a dual reporter gene for fluorescence and magnetic resonance imaging.


Assuntos
Genes Reporter , Transportador 1 de Ânion Orgânico Específico do Fígado/metabolismo , Imagem por Ressonância Magnética , Sarcoma , Animais , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Imagem Óptica , Sarcoma/diagnóstico por imagem , Sarcoma/genética , Sarcoma/metabolismo
12.
J Radiol Case Rep ; 12(7): 1-9, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30651912

RESUMO

Improvements in techniques, contrast agents, and catheter design have significantly decreased angiography-related neurological deficits and complications. This article reports a case involving an angiographic total obliteration arteriovenous malformation (AVM) in a patient with an acute infarction in the artery of Percheron (AOP) distribution following angiography. Furthermore, imaging of an AOP acute infarction in cerebral angiography is presented.


Assuntos
Angiografia Cerebral/efeitos adversos , Artérias Cerebrais/diagnóstico por imagem , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/etiologia , Angiografia Digital , Artérias Cerebrais/anatomia & histologia , Infarto Cerebral/terapia , Diagnóstico Diferencial , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/complicações , Malformações Arteriovenosas Intracranianas/terapia , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/etiologia , Angiografia por Ressonância Magnética , Pessoa de Meia-Idade , Prognóstico
13.
PLoS One ; 12(12): e0188948, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29220356

RESUMO

The cerebral hypoperfusion caused by chronic progressive stenosis or occlusion of intracranial arteries in moyamoya disease can be treated by direct bypass or indirect revascularization procedures. The extent of collaterals from the external carotid artery (ECA) after indirect revascularization surgery is the key point of angiographic follow-up, and the invasiveness of angiography impelled us to investigate the role of ultrasonography in the evaluation of collaterals. We hypothesized that the collaterals shown on angiography might produce corresponding hemodynamic changes in color Doppler ultrasonography. We prospectively recruited moyamoya patients who underwent indirect revascularization surgery and received both preoperative and postoperative angiography and color Doppler ultrasound studies. The collaterals on angiography were graded according to Matsushima method. A total of 21 patients (age, 17 ± 10.2 years) with 24 operated hemispheres were enrolled. Patients who showed better collateral establishment by angiography had higher end-diastolic velocity (EDV), lower resistance index (RI), and larger flow volume in the superficial temporal artery (STA) and ECA (all p < 0.05). In STA, increase of EDV greater than 13.5 cm/sec or reduction of RI greater than 0.19 after operation corresponded to 94% of Matsushima grade A+B. In ECA, post-operative EDV greater than 22 cm/sec or increase of EDV greater than 6.4 cm/sec also corresponded to 94% of Matsushima grade A+B. Our findings revealed potential roles of color Doppler ultrasonography in identifying patients with poor collaterals after indirect revascularization procedures.


Assuntos
Revascularização Cerebral/métodos , Doença de Moyamoya/cirurgia , Ultrassonografia Doppler em Cores/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Doença de Moyamoya/diagnóstico por imagem , Período Pós-Operatório , Adulto Jovem
14.
Sci Rep ; 7(1): 3587, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28620162

RESUMO

The aim of the current study was to develop an iron oxide nanoparticle (ION) labelling and magnetic resonance imaging (MRI)-based protocol to allow visualization of the differentiation process of mesenchymal stem cells (MSCs) into neural-like cells (NCs) in vitro. Ferucarbotran, a clinically available ION, which can be visualized under MRI, is used for tracking cells implanted in vivo. The NCs were verified morphologically and histologically by light microscopy, and their functions were verified by measuring their action potentials. Conformational conversion of axon-like structures was observed under light microscopy. These NCs exhibited frequent, active action potentials compared with cells that did not undergo neural differentiation. The labelling of ION had no influence on the morphological and functional differentiation capacity of the MSCs. We conclude that the MSCs that were differentiated into NCs exhibited in vitro activity potential firing and may be used to replace damaged neurons.


Assuntos
Diferenciação Celular , Meios de Contraste/metabolismo , Dextranos/metabolismo , Imagem por Ressonância Magnética/métodos , Células-Tronco Mesenquimais/fisiologia , Neurônios/fisiologia , Coloração e Rotulagem/métodos , Potenciais de Ação , Células Cultivadas , Histocitoquímica , Humanos , Nanopartículas de Magnetita , Células-Tronco Mesenquimais/efeitos dos fármacos , Microscopia
16.
Ultrasound Med Biol ; 42(12): 2844-2851, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27639432

RESUMO

The marked cerebral hypoperfusion of moyamoya disease (MMD) can be treated with encephaloduroarteriosynangiosis (EDAS), an indirect revascularization surgery. Collateral establishment after the surgery is a gradual process; thus, easy access to serial assessment is of great importance. We prospectively recruited 15 pediatric moyamoya patients who underwent EDAS surgeries on a total of 19 hemispheres. Ultrasonography of extracranial and intracranial arteries was performed pre-operatively and post-operatively at 1, 3 and 6 mo. Among the extracranial arteries, the superficial temporal artery had the most pronounced increase in flow velocity and decrease in flow resistance from 1 mo post-surgery (p < 0.01). Among the large intracranial arteries, a significant increase in peak systolic velocity was observed in the anterior cerebral artery from 3 mo post-surgery (p < 0.05). These findings indicate significant hemodynamic changes on ultrasonography in pediatric moyamoya patients after indirect revascularization surgery.


Assuntos
Artéria Carótida Interna/cirurgia , Artérias Cerebrais/cirurgia , Revascularização Cerebral/métodos , Doença de Moyamoya/cirurgia , Ultrassonografia/métodos , Adolescente , Adulto , Artéria Carótida Interna/diagnóstico por imagem , Artérias Cerebrais/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Cuidados Pós-Operatórios/métodos , Cuidados Pré-Operatórios/métodos , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
17.
Int J Cardiol ; 221: 772-6, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27428320

RESUMO

BACKGROUND: Proper patient selection criteria for treatment of carotid chronic total occlusion (CTO) are unclear. This study was designed to predict procedure successful rate and 1-year patency after carotid artery stenting (CAS) for carotid CTO using pre-procedural CTA. METHODS: Patients with CTO detected on CTA who underwent recanalization within 3months were divided into those with occlusions at (or distal to) the clinoid segment of the internal carotid artery (group A) and those with occlusions proximal to the clinoid segment (group B) and outcomes were compared between groups. RESULTS: Technical success rates, major complications, and re-occlusions within 1-year were 52%, 22%, 91% in group A (N=23), and 89%, 0%, 0% in group B (N=19), respectively. Diabetes was more frequent in group A (43%) compared with group B (11%). CONCLUSION: CTA may play a role in predicting successful rate and 1-year patency for endovascular recanalization in carotid CTO.


Assuntos
Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/cirurgia , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Angiografia por Tomografia Computadorizada/tendências , Procedimentos Endovasculares/tendências , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Stents/tendências , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular/fisiologia
18.
Sci Rep ; 6: 30179, 2016 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-27452722

RESUMO

Carotid bruits are systolic sounds associated with turbulent blood flow through atherosclerotic stenosis in the neck. They are audible intermittent high-frequency (above 200 Hz) sounds mixed with background noise and transmitted low-frequency (below 100 Hz) heart sounds that wax and wane periodically. It is a nontrivial task to extract both bruits and heart sounds with high fidelity for further computer-aided auscultation and diagnosis. In this paper we propose a rolling ball sifting algorithm that is capable to filter signals with a sharper frequency selectivity mechanism in the time domain. By rolling two balls (one above and one below the signal) of a suitable radius, the balls are large enough to roll over bruits and yet small enough to ride on heart sound waveforms. The high-frequency bruits can then be extracted according to a tangibility criterion by using the local extrema touched by the balls. Similarly, the low-frequency heart sounds can be acquired by a larger radius. By visualizing the periodicity information of both the extracted heart sounds and bruits, the proposed visual inspection method can potentially improve carotid bruit diagnosis accuracy.


Assuntos
Artérias Carótidas/fisiologia , Coração/fisiologia , Algoritmos , Aterosclerose/fisiopatologia , Constrição Patológica/fisiopatologia , Auscultação Cardíaca/métodos , Humanos , Fluxo Sanguíneo Regional/fisiologia , Som
19.
Neuroradiology ; 58(8): 753-63, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27185610

RESUMO

INTRODUCTION: This study aims to review the diagnostic performance of computed tomography (CT) and magnetic resonance imaging (MRI) in symptomatic dural arteriovenous fistula (DAVF). METHODS: EMBASE, PubMed, and Cochrane Library were searched until April 2015 for studies which compared CT, MRI, or both with angiography for the detection of DAVF. The diagnostic performances of MRI and CT were indirectly compared using modality as a covariate in the analysis. RESULTS: Thirteen studies met our inclusion criteria. MRI had a sensitivity of 0.90 (95 % confidence interval (CI) = 0.83-0.94) and specificity of 0.94 (95 % CI = 0.90-0.96). CT had a sensitivity of 0.80 (95 % CI = 0.62-0.90) and specificity of 0.87 (95 % CI = 0.74-0.94). MRI showed better diagnostic performance than CT (p = 0.02). Contrast medium use and time-resolved MR angiography did not improve MRI diagnostic performance (p = 0.31 and 0.44, respectively). CONCLUSION: Both CT and MRI had good diagnostic performance. MRI was better than CT on the detection of symptomatic intracranial dural arteriovenous fistula in the indirect comparison.


Assuntos
Angiografia Cerebral/métodos , Angiografia por Tomografia Computadorizada/métodos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Angiografia Cerebral/estatística & dados numéricos , Angiografia por Tomografia Computadorizada/estatística & dados numéricos , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/epidemiologia , Angiografia por Ressonância Magnética/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Prevalência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Avaliação de Sintomas
20.
J Neurol Sci ; 365: 76-81, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27206880

RESUMO

PURPOSE: To introduce the combination of suction thrombectomy (ST) and balloon maceration (BM) for the management of dural venous sinus thrombosis (DVST). MATERIALS AND METHODS: Ten consecutive patients (average age, 53±15years; range, 30 to 73years) with DVST treated by ST after BM were evaluated including location of DVST, imaging presentation, procedural findings, and 3-month modified Rankin scale (mRS). RESULTS: All 10 patients had evidence of venous infarct on MR or CT. In addition, seven patients had intracerebral hemorrhage (ICH), one had subarachnoid hemorrhage (SAH), and one had both ICH and SAH. More than one sinus was involved in nine patients. ST after BM was technically successful in all patients, and angiographic relief of venous congestion and good outcome (3-month mRS 0 or 1) was achieved in eight patients (80%). The average procedural time was 73.5±24.7min. Two patients who were in coma status had negative outcomes, and one had a known chronic thrombotic segment refractory to treatment. No recurrent thrombosis of recanalized sinus was found on follow-up MR venography in six patients and CT venography in two patients. CONCLUSION: BM followed by ST is a promising technique for the treatment of acute DVST.


Assuntos
Procedimentos Neurocirúrgicos/métodos , Trombose dos Seios Intracranianos/cirurgia , Trombectomia/métodos , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/cirurgia , Angiografia Cerebral , Hemorragia Cerebral/complicações , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/patologia , Hemorragia Cerebral/cirurgia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Flebografia , Estudos Retrospectivos , Índice de Gravidade de Doença , Trombose dos Seios Intracranianos/complicações , Trombose dos Seios Intracranianos/diagnóstico por imagem , Trombose dos Seios Intracranianos/patologia , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/patologia , Hemorragia Subaracnóidea/cirurgia , Sucção , Tomografia Computadorizada por Raios X , Resultado do Tratamento
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