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1.
Surg Open Sci ; 17: 40-43, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38268776

RESUMO

Anorectal fistula is a common, chronic condition, and is primarily managed surgically. Herein, we provide a contemporary review of the relevant etiology and anatomy anorectal fistula, treatment recommendations that summarize relevant outcomes and alternative considerations, in particular when to refer to a fistula expert.

2.
J Clin Neurol ; 19(6): 573-580, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37455509

RESUMO

BACKGROUND AND PURPOSE: We aimed to determine whether structural brain connectivity is significantly associated with the response to sumatriptan in patients with migraine. METHODS: We retrospectively enrolled patients with newly diagnosed migraine who underwent brain diffusion-tensor imaging (DTI) at the time of diagnosis, with regular follow-up for at least 6 months after the initial diagnosis. Patients were classified into good- and poor-responder groups according to their response to sumatriptan. We analyzed the structural connectivity using DTI by applying graph theory using DSI Studio software. RESULTS: We enrolled 59 patients (35 good responders and 24 poor responders) and 30 healthy controls. Global structural connectivity differed significantly between patients with migraine and healthy controls, while local structural connectivity differed significantly between good and poor responders. The betweenness centrality was lower in good responders than in poor responders in the left lateral geniculate thalamic nucleus (26.078 vs. 41.371, p=0.039) and right medial mediodorsal magnocellular thalamic nucleus (60.856 vs. 90.378, p=0.021), whereas was higher in good responders in the left lateral pulvinar thalamic nucleus (98.365 vs. 50.347, p=0.003) and right medial pulvinar thalamic nucleus (216.047 vs. 156.651, p=0.036). CONCLUSIONS: We found that structural connectivity in patients with migraine differed from that in healthy controls. Moreover, the local structural connectivity varied with the response to sumatriptan, which suggests that structural connectivity is a useful factor for predicting how a patient will respond to sumatriptan.

3.
Sensors (Basel) ; 23(6)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36991711

RESUMO

Cybersecurity is a growing concern in today's interconnected world. Traditional cybersecurity approaches, such as signature-based detection and rule-based firewalls, are often limited in their ability to effectively respond to evolving and sophisticated cyber threats. Reinforcement learning (RL) has shown great potential in solving complex decision-making problems in various domains, including cybersecurity. However, there are significant challenges to overcome, such as the lack of sufficient training data and the difficulty of modeling complex and dynamic attack scenarios hindering researchers' ability to address real-world challenges and advance the state of the art in RL cyber applications. In this work, we applied a deep RL (DRL) framework in adversarial cyber-attack simulation to enhance cybersecurity. Our framework uses an agent-based model to continuously learn from and adapt to the dynamic and uncertain environment of network security. The agent decides on the optimal attack actions to take based on the state of the network and the rewards it receives for its decisions. Our experiments on synthetic network security show that the DRL approach outperforms existing methods in terms of learning optimal attack actions. Our framework represents a promising step towards the development of more effective and dynamic cybersecurity solutions.

4.
Retina ; 43(5): 747-754, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36729565

RESUMO

PURPOSE: To investigate the quantitative characteristics of anastomoses of macular neovascularization (MNV) in neovascular age-related macular degeneration using optical coherence tomography angiography according to the frequency of intravitreal injections. METHODS: Eighty-six eyes of 86 patients treated for neovascular age-related macular degeneration were classified into two groups based on the number of intravitreal injections administered over 12 months: stable (<3) and unstable (≥3). Anastomotic areas were defined as areas surrounded by neighboring vessels in the MNV; their total number, mean area, maximal and minimal diameters (i.e., maximal and minimum Feret diameters), and ratio (Feret aspect ratio) were analyzed in the inner and outer areas of the MNV. RESULTS: Forty-four and 42 eyes were classified into the stable and unstable groups, respectively. The eyes in the unstable group had larger anastomotic areas with longer minimum Feret diameters and longer perimeters in the outer MNV. In the logistic regression analysis, instability was associated with a larger anastomotic area and a longer minimum Feret diameter in the outer MNV. Multivariate analysis revealed that a longer minimum Feret diameter in the outer MNV was the most significant factor ( P = 0.03). CONCLUSION: The quantitative characteristics of the anastomotic areas in the MNV might indicate the need for intravitreal injections in patients with neovascular age-related macular degeneration.


Assuntos
Neovascularização de Coroide , Degeneração Macular , Neovascularização Retiniana , Degeneração Macular Exsudativa , Humanos , Lactente , Inibidores da Angiogênese/uso terapêutico , Angiofluoresceinografia/métodos , Neovascularização Retiniana/tratamento farmacológico , Neovascularização de Coroide/diagnóstico , Neovascularização de Coroide/tratamento farmacológico , Neovascularização de Coroide/complicações , Tomografia de Coerência Óptica/métodos , Degeneração Macular/complicações , Injeções Intravítreas , Degeneração Macular Exsudativa/diagnóstico , Degeneração Macular Exsudativa/tratamento farmacológico , Degeneração Macular Exsudativa/complicações , Estudos Retrospectivos
5.
J Pharmacol Exp Ther ; 384(1): 205-223, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36310035

RESUMO

One important function of the vascular blood-brain barrier (BBB) is to facilitate neuroimmune communication. The BBB fulfills this function, in part, through its ability to transport cytokines and chemokines. C-C motif chemokine receptor 2 (CCL2) (MCP-1) and C-C motif chemokine receptor 5 (CCL5) (RANTES) are proinflammatory chemokines that mediate neuroimmune responses to acute insults and aspects of brain injury and neurodegenerative diseases; however, a blood-to-brain transport system has not been evaluated for either chemokine in vivo. Therefore, we determined whether CCL2 and CCL5 in blood can cross the intact BBB and enter the brain. Using CD-1 mice, we found that 125I-labeled CCL2 and CCL5 crossed the BBB and entered the brain parenchyma. We next aimed to identify the mechanisms of 125I-CCL2 and 125I-CCL5 transport in an in situ brain perfusion model. We found that both heparin and eprodisate inhibited brain uptake of 125I-CCL2 and 125I-CCL5 in situ, whereas antagonists of their receptors, CCR2 or CCR5, respectively, did not, suggesting that heparan sulfates at the endothelial surface mediate BBB transport. Finally, we showed that CCL2 and CCL5 transport across the BBB increased following a single injection of 0.3 mg/kg lipopolysaccharide. These data demonstrate that CCL2 and CCL5 in the brain can derive, in part, from the circulation, especially during systemic inflammation. Further, binding to the BBB-associated heparan sulfate is a mechanism by which both chemokines can cross the intact BBB, highlighting a novel therapeutic target for treating neuroinflammation. SIGNIFICANCE STATEMENT: Our work demonstrates that C-C motif chemokine ligand 2 (CCL2) and C-C motif chemokine ligand 5 (CCL5) can cross the intact blood-brain barrier and that transport is robustly increased during inflammation. These data suggest that circulating CCL2 and CCL5 can contribute to brain levels of each chemokine. We further show that the transport of both chemokines is inhibited by heparin and eprodisate, suggesting that CCL2/CCL5-heparan sulfate interactions could be therapeutically targeted to limit accumulation of these chemokines in the brain.


Assuntos
Barreira Hematoencefálica , Heparina , Camundongos , Animais , Barreira Hematoencefálica/metabolismo , Heparina/farmacologia , Ligantes , Quimiocinas/metabolismo , Inflamação/tratamento farmacológico , Receptores de Quimiocinas , Heparitina Sulfato
6.
J Clin Neurophysiol ; 40(4): 364-370, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34510091

RESUMO

PURPOSE: The aims of this study were to identify (1) the spectrum of ictal-interictal continuum (IIC) using the two dimensions of 2HELPS2B score and background suppression and (2) the response to subsequent anti-seizure drugs depends on the spectrum of IIC. METHODS: The study prospectively enrolled 62 patients with IIC on EEG. The diagnosis of nonconvulsive status epilepticus was attempted with Salzburg criteria as well as clinical and neuroimaging data. IICs were dichotomized into patients with nonconvulsive status epilepticus and coma-IIC. The 2HELPS2B score was evaluated as the original proposal. The suppression ratio was analyzed with Persyst software. RESULTS: Forty-seven cases (75.8%) were nonconvulsive status epilepticus-IIC and 15 cases (24.2%) were coma-IIC. Multivariate analysis revealed that the 2HELPS2B score was the only significant variable dichotomizing the spectrum of IIC (odds ratio, 3.0; 95% confidence interval, 1.06-8.6; P = 0.03 for nonconvulsive status epilepticus-IIC). In addition, the suppression ratio was significantly negatively correlated with 2HELPS2B scores (Spearman coefficient = -0.37, P = 0.004 for left hemisphere and Spearman coefficient = -0.3, P = 0.02 for right hemisphere). Furthermore, patients with higher 2HELPS2B score (74% [14/19] in ≥2 points vs. 44% [14/32] in <2 points, P = 0.03 by χ 2 test) and lower suppression ratio (62% [23/37] in ≤2.18 vs. 35% [6/17] in >2.18, P = 0.06 by χ 2 test) seemed to be more responsive to subsequent anti-seizure drug. CONCLUSIONS: The 2HELPS2B score and background suppression can be used to distinguish the spectrum of IIC and thereby predict the response to subsequent anti-seizure drug.


Assuntos
Eletroencefalografia , Estado Epiléptico , Humanos , Eletroencefalografia/métodos , Coma , Estado Epiléptico/diagnóstico , Neuroimagem
7.
J Neuroimaging ; 33(1): 147-155, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36068702

RESUMO

BACKGROUND AND PURPOSE: Recognizing the location and length of the thrombus responsible for large vessel occlusion in patients with acute ischemic stroke can facilitate effective endovascular recanalization therapy (ERT). We hypothesized that the aliasing or dipole effect produced by filtered-phase susceptibility-weighted imaging (SWI) would facilitate thrombus delineation. METHODS: Of the patients with middle cerebral artery occlusion who underwent ERT, we screened those who underwent noncontrast CT (NCCT), multiphase CT angiography (mCTA), and SWI before the endovascular procedure. We used an arbitrary index termed measurement of equivalence in thrombus assessed by digital subtraction angiography (METAD) defined as having the same location as the thrombus observed in the digital subtraction angiography (DSA) and length differing by less than 5 mm. For NCCT, mCTA, SWI_m (magnitude), and SWI_p (phase), the length of the thrombus and METAD were assessed. RESULTS: The mean lengths of the thrombi determined using NCCT, mCTA, SWI_m, SWI_p, and DSA were 14.03, 13.47, 13.89, 9.93, and 8.96 mm, respectively. The absolute agreement for thrombus length was excellent for SWI_p and DSA (intraclass correlation coefficient [ICC] = .96), moderate for SWI_m and DSA (ICC = .53), and poor for mCTA and DSA (ICC = .14). The METADs were 26.7%, 40.0%, 33.3%, and 73.3% for NCCT, mCTA, SWI_m, and SWI_p, respectively. The METADs for NCCT and SWI_p were significantly different (p = .045) and those for mCTA and SWI_m were not (p = .537 and .093, respectively). CONCLUSIONS: The SWI_p was best matched with the DSA for the measurement of the lengths and locations of thrombi. The use of pre-thrombectomy SWI_p imaging for acute ischemic stroke may facilitate a successful ERT strategy.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Trombose , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombose/diagnóstico por imagem , Infarto da Artéria Cerebral Média , Imageamento por Ressonância Magnética , Angiografia por Tomografia Computadorizada/métodos , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Estudos Retrospectivos , Angiografia Cerebral/métodos
8.
Sci Rep ; 12(1): 10821, 2022 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-35752643

RESUMO

The clinical implication of en face imaging of Haller vessels and macular neovascularization (MNV) in neovascular age-related macular degeneration (nAMD) is not well established. The purpose of this study is to investigate whether the early-phase morphology of en face Haller vessel and MNV is related to the injection frequency and visual outcome in treatment-naïve nAMD. En face images of Haller vessel and MNV were acquired from 52 eyes at baseline, after three loading doses and at 12 months later using optical coherence tomography (OCT) and OCT angiography. Vessel area, diameter, length, intersection number, fractal dimension, and lacunarity were calculated. Patients were classified according to the injection frequency (< 5 as the infrequent group) and visual gain (≥ 0.3 logMAR) over 12 months. The infrequent group was associated with a longer Haller vessel length after loading doses (OR 3.05, P = 0.01), while visual gain was associated with a smaller maximal MNV diameter after loading doses (OR 0.22, P = 0.03). A predictive model for frequent injection based on the Haller vessel length demonstrated an AUC of 0.71. In conclusion, the en face Haller vessel and MNV morphology after loading doses can be used as biomarkers for the injection frequency and visual gain during the first year in treatment-naïve nAMD patients.


Assuntos
Neovascularização de Coroide , Degeneração Macular , Neovascularização Retiniana , Degeneração Macular Exsudativa , Inibidores da Angiogênese/uso terapêutico , Neovascularização de Coroide/diagnóstico por imagem , Neovascularização de Coroide/tratamento farmacológico , Angiofluoresceinografia/métodos , Humanos , Injeções Intravítreas , Degeneração Macular/diagnóstico por imagem , Degeneração Macular/tratamento farmacológico , Neovascularização Retiniana/tratamento farmacológico , Tomografia de Coerência Óptica/métodos , Degeneração Macular Exsudativa/tratamento farmacológico
9.
Seizure ; 95: 84-89, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35030375

RESUMO

OBJECTIVE: This study aimed to evaluate the differences in hippocampal structural volumes and intra-hippocampal networks between patients with status epilepticus (SE) and healthy controls. METHODS: We enrolled 45 patients with SE and 35 age- and sex-matched healthy controls. We excluded patients with active structural lesions, which could be a direct cause of SE, but included patients with co-existing lesions. Co-existing lesions were defined as any lesions possibly related to the occurrence of SE, including encephalomalacia, cavernous malformation, dural arteriovenous fistula, and normal pressure hydrocephalus, etc. We divided 45 patients into those with co-existing lesions (n = 21) and those without co-existing lesions (n = 24). We conducted a volumetric analysis using FreeSurfer (version 7), and the intra-hippocampal structural co-variance network was analyzed with a graph theoretical analysis based on the structural volumes of the hippocampal subfields. RESULTS: The structural volumes and intra-hippocampal structural co-variance networks were not different between patients with and without co-existing lesions. However, both structural volumes and intra-hippocampal structural co-variance networks were significantly different in patients with SE compared to healthy controls, and the ratio of the volume difference: [(volume of controls-volume of patients)/volume of controls] was highest in the left hippocampus (0.195), left amygdala (0.143), left thalamus (0.126), and right cortex (0.084). In addition, the global connectivity measurements including radius, diameter, eccentricity, and assortativity were significantly increased, and the small-worldness index was significantly decreased in patients with SE. Notably, structural volumes were negatively related to age but not to the duration of SE. SIGNIFICANCE: Our study revealed significant alterations in structural volumes and intra-hippocampal structural co-variance networks in patients with SE compared to healthy controls, even though hippocampal atrophy was not evident on visual analysis; this is likely due to the direct effect of SE itself.


Assuntos
Imageamento por Ressonância Magnética , Estado Epiléptico , Tonsila do Cerebelo/patologia , Atrofia/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Estado Epiléptico/diagnóstico por imagem , Estado Epiléptico/patologia
10.
Neuroradiology ; 64(7): 1351-1357, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35013760

RESUMO

PURPOSE: The hypothalamus plays a pivotal role in the pathogenesis of narcolepsy. This study aimed to evaluate the differences in the structural covariance network of thehypothalamus based on volume differences between patients with narcolepsy and healthy controls. METHODS: We retrospectively enrolled 15 patients with narcolepsy and 19 healthy controls.All subjects underwent three-dimensional T1-weighted imaging using a 3-T magnetic resonance imaging scanner. Hypothalamic subunits were segmented, and the volumes of individual hypothalamic subunits were obtained using the FreeSurfer program. Subsequently, we conducted a structural covariance network analysis of the subunit volumes with graph theory using the BRAPH program in patients with narcolepsy and in healthy controls. RESULTS: There were no significant differences in the volumes of the entire right and left hypothalamus nor in the hypothalamic subunit between patients with narcolepsy and healthy controls. However, we found significant differences in the structural covariance network in the hypothalamus between these groups. The characteristic path length was significantly lower in patients with narcolepsy than in healthy controls (1.698 vs. 2.831, p = 0.001). However, other network measures did not differ between patients with narcolepsy and healthy controls. CONCLUSION: We found that the structural covariance network of the hypothalamus, as assessed from the subunit volumes of hypothalamic regions using a graph theoretical analysis, is different in patients with narcolepsy compared to healthy controls. These findings may contribute to the understanding of the pathogenesis of narcolepsy.


Assuntos
Hipotálamo , Narcolepsia , Estudos de Casos e Controles , Humanos , Hipotálamo/diagnóstico por imagem , Hipotálamo/patologia , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Narcolepsia/diagnóstico por imagem , Narcolepsia/patologia , Estudos Retrospectivos
11.
Neuroradiology ; 64(2): 313-321, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34251501

RESUMO

PURPOSE: The aim of this study was to determine whether anti-seizure medication (ASM) response is associated with structural connectivity in diffusion tensor imaging (DTI) or functional co-variance network in arterial spin labeling (ASL) magnetic resonance imaging (MRI) in patients with focal epilepsy. METHODS: In this retrospective study conducted at a tertiary hospital, we enrolled 105 patients with focal epilepsy, of which 64 patients were good ASM responders, and 41 patients were poor ASM responders. All patients showed normal MRI findings on visual inspection and underwent DTI and ASL MRI from August 2018 to July 2020, with regular follow-up for at least 12 months after epilepsy diagnosis while taking ASMs. We calculated the structural connectivity based on DTI and functional co-variance network based on ASL MRI by using graph theory and analyzed their differences in relation to the ASM response. RESULTS: No differences were observed in structural connectivity between the good and poor ASM responders. However, significant differences were observed in functional co-variance network between the good and poor ASM responders. In comparison with good ASM responders, poor ASM responders showed a significantly greater characteristic path length (2.557 vs. 1.753, p = 0.034) and a lower local efficiency (2.311 vs. 3.927, p = 0.048). CONCLUSION: Significant differences were observed in functional co-variance network based on ASL MRI between the good and poor ASM responders. These findings suggest that functional co-variance network could serve as a new biomarker of ASM response in focal epilepsy.


Assuntos
Imagem de Tensor de Difusão , Epilepsias Parciais , Epilepsias Parciais/diagnóstico por imagem , Epilepsias Parciais/tratamento farmacológico , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Convulsões , Marcadores de Spin
12.
Sleep Breath ; 26(2): 633-640, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34236578

RESUMO

PURPOSE: We evaluated the feasibility of machine learning analysis using diffusion tensor imaging (DTI) parameters to identify patients with idiopathic rapid eye movement (REM) sleep behavior disorder (RBD). We hypothesized that patients with idiopathic RBD could be identified via machine learning analysis based on DTI. METHODS: We enrolled 20 patients with newly diagnosed idiopathic RBD at a tertiary hospital. We also included 20 healthy subjects as a control group. All of the subjects underwent DTI. We obtained the conventional DTI parameters and structural connectomic profiles from the DTI. We investigated the differences in conventional DTI measures and structural connectomic profiles between patients with idiopathic RBD and healthy controls. We then used machine learning analysis using a support vector machine (SVM) algorithm to identify patients with idiopathic RBD using conventional DTI and structural connectomic profiles. RESULTS: Several regions showed significant differences in conventional DTI measures and structural connectomic profiles between patients with idiopathic RBD and healthy controls. The SVM classifier based on conventional DTI measures revealed an accuracy of 87.5% and an area under the curve of 0.900 to identify patients with idiopathic RBD. Another SVM classifier based on structural connectomic profiles yielded an accuracy of 75.0% and an area under the curve of 0.833. CONCLUSION: Our findings demonstrate the feasibility of machine learning analysis based on DTI to identify patients with idiopathic RBD. The conventional DTI parameters might be more important than the structural connectomic profiles in identifying patients with idiopathic RBD.


Assuntos
Conectoma , Transtorno do Comportamento do Sono REM , Imagem de Tensor de Difusão/métodos , Humanos , Aprendizado de Máquina , Transtorno do Comportamento do Sono REM/diagnóstico por imagem , Máquina de Vetores de Suporte
13.
J Neurol ; 269(1): 316-322, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34052886

RESUMO

OBJECTIVE: The hypothalamus is one of the key structures involved in the pathophysiology of cluster headaches. This study aimed to analyze the volume of hypothalamic subunits and structural covariance networks in the hypothalamus of patients with cluster headache. METHODS: We retrospectively enrolled 18 patients with episodic cluster headache and 18 age- and sex-matched healthy controls. We calculated individual structural volumes in ten hypothalamic subunits using three-dimensional T1-weighted imaging and the FreeSurfer program, which conducted an automated segmentation based on deep convolutional neural networks. We also performed an analysis of the structural covariance network in the hypothalamus using graph theory and the BRAPH program. We compared the volumes of hypothalamic subunits and structural covariance networks in the hypothalamus of patients with cluster headache versus those of healthy controls. RESULTS: There were no significant differences in the structural volumes of the whole hypothalamus and hypothalamic subunits between patients with cluster headache and healthy controls. However, patients with cluster headache had significant alterations of the structural covariance network in the hypothalamus compared to that of healthy controls. The network measure of small-worldness index in patients with cluster headache was lower than that in healthy controls (0.844 vs. 0.955, p = 0.004). CONCLUSION: We demonstrated a significant difference in the structural covariance network in the hypothalamus of patients with cluster headache versus those of healthy controls. These findings could be related to the pathogenesis of cluster headache.


Assuntos
Cefaleia Histamínica , Cefaleia Histamínica/diagnóstico por imagem , Humanos , Hipotálamo , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Estudos Retrospectivos
14.
Front Immunol ; 13: 1015840, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36713406

RESUMO

Nanoparticle vaccines usually prime stronger immune responses than soluble antigens. Within this class of subunit vaccines, the recent development of computationally designed self-assembling two-component protein nanoparticle scaffolds provides a powerful and versatile platform for displaying multiple copies of one or more antigens. Here we report the generation of three different nanoparticle immunogens displaying 60 copies of p67C, an 80 amino acid polypeptide from a candidate vaccine antigen of Theileria parva, and their immunogenicity in cattle. p67C is a truncation of p67, the major surface protein of the sporozoite stage of T. parva, an apicomplexan parasite that causes an often-fatal bovine disease called East Coast fever (ECF) in sub-Saharan Africa. Compared to I32-19 and I32-28, we found that I53-50 nanoparticle scaffolds displaying p67C had the best biophysical characteristics. p67C-I53-50 also outperformed the other two nanoparticles in stimulating p67C-specific IgG1 and IgG2 antibodies and CD4+ T-cell responses, as well as sporozoite neutralizing capacity. In experimental cattle vaccine trials, p67C-I53-50 induced significant immunity to ECF, suggesting that the I53-50 scaffold is a promising candidate for developing novel nanoparticle vaccines. To our knowledge this is the first application of computationally designed nanoparticles to the development of livestock vaccines.


Assuntos
Doenças dos Bovinos , Vacinas Protozoárias , Theileria parva , Theileriose , Bovinos , Animais , Antígenos
16.
J Clin Neurosci ; 91: 327-333, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34373048

RESUMO

The aim of this study was to evaluate the feasibility of using a machine learning approach based on diffusion tensor imaging (DTI) to identify patients with juvenile myoclonic epilepsy. We analyzed the usefulness of combining conventional DTI measures and structural connectomic profiles. This retrospective study was conducted at a tertiary hospital. We enrolled 55 patients with juvenile myoclonic epilepsy. All of the subjects underwent DTI from January 2017 to March 2020. We also enrolled 58 healthy subjects as a normal control group. We extracted conventional DTI measures and structural connectomic DTI profiles. We employed the support vector machines (SVM) algorithm to classify patients with juvenile myoclonic epilepsy and healthy subjects based on the conventional DTI measures and structural connectomic profiles. The SVM classifier based on conventional DTI measures had an accuracy of 68.1% and an area under the curve (AUC) of 0.682. Another SVM classifier based on the structural connectomic profiles demonstrated an accuracy of 72.7% and an AUC of 0.727. The SVM classifier based on combining the conventional DTI measures and structural connectomic profiles had an accuracy of 81.8% and an AUC of 0.818. DTI using machine learning is useful for classifying patients with juvenile myoclonic epilepsy and healthy subjects. Combining both the conventional DTI measures and structural connectomic profiles results in a better classification performance than using conventional DTI measures or the structural connectomic profiles alone to identify juvenile myoclonic epilepsy.


Assuntos
Conectoma , Epilepsia Mioclônica Juvenil , Imagem de Tensor de Difusão , Humanos , Aprendizado de Máquina , Epilepsia Mioclônica Juvenil/diagnóstico por imagem , Estudos Retrospectivos , Máquina de Vetores de Suporte
17.
BMC Neurol ; 21(1): 330, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34452597

RESUMO

BACKGROUND: The aim of this study was to investigate alterations in structural connectivity and structural co-variance network in patients with focal cortical dysplasia (FCD). METHODS: We enrolled 37 patients with FCD and 35 healthy controls. All subjects underwent brain MRI with the same scanner and with the same protocol, which included diffusion tensor imaging (DTI) and T1-weighted imaging. We analyzed the structural connectivity based on DTI, and structural co-variance network based on the structural volume with T1-weighted imaging. We created a connectivity matrix and obtained network measures from the matrix using the graph theory. We tested the difference in network measure between patients with FCD and healthy controls. RESULTS: In the structural connectivity analysis, we found that the local efficiency in patients with FCD was significantly lower than in healthy controls (2.390 vs. 2.578, p = 0.031). Structural co-variance network analysis revealed that the mean clustering coefficient, global efficiency, local efficiency, and transitivity were significantly decreased in patients with FCD compared to those in healthy controls (0.527 vs. 0.635, p = 0.036; 0.545 vs. 0.648, p = 0.026; 2.699 vs. 3.801, p = 0.019; 0.791 vs. 0.954, p = 0.026, respectively). CONCLUSIONS: We demonstrate that there are significant alterations in structural connectivity, based on DTI, and structural co-variance network, based on the structural volume, in patients with FCD compared to healthy controls. These findings suggest that focal lesions with FCD could affect the whole-brain network and that FCD is a network disease.


Assuntos
Imagem de Tensor de Difusão , Malformações do Desenvolvimento Cortical , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Neuroimagem
18.
Korean J Ophthalmol ; 35(5): 397-409, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34344131

RESUMO

PURPOSE: The present study aimed to quantify various factors of vessel morphology, including vessel diameter, length, and complexity (fractal dimension and lacunarity) of both choroidal neovascularization (CNV) and en face Haller vessels using optical coherence tomography angiography (OCTA) and en face structural optical coherence tomography in typical neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV) and to identify factors associated with visual acuity (VA) loss and number of injections within a year after the day of OCTA. METHODS: We retrospectively analyzed 43 eyes of nAMD patients and 33 eyes of PCV patients whose OCTA was performed at least 12 months after an initial anti-vascular endothelial growth factor treatment. Quantitative parameters, including vessel area, vessel diameter, vessel length, fractal dimension, and lacunarity were analyzed from en face images of CNV and Haller vessels. Clinical information, including logarithm of the minimum angle of resolution visual acuity and injection number of anti-vascular endothelial growth factor were acquired after 12 months from OCTA date. Using logistic regression analyses, parameters associated with logarithm of the minimum angle of resolution VA loss of 0.2 or more (VA loss group) and a number of injections of four or more (unstable group) after 12 months were analyzed. RESULTS: In typical nAMD, the VA loss group was associated with a smaller number of intersections of Haller vessels. The unstable group was associated with an increased lacunarity of CNV in typical nAMD. In PCV, both VA loss and unstable groups were associated with a higher maximal diameter of Haller vessels. CONCLUSIONS: VA loss and injection number of nAMD and PCV 12 months after OCTA imaging were associated with different morphological parameters of CNV and Haller vessels. Therefore, quantitative analyses of both CNV and Haller vessels from OCTA and en face optical coherence tomography might provide prognostic information about visual outcome and injection frequency within 12 months after OCTA imaging.


Assuntos
Neovascularização de Coroide , Degeneração Macular , Degeneração Macular Exsudativa , Inibidores da Angiogênese/uso terapêutico , Neovascularização de Coroide/diagnóstico por imagem , Neovascularização de Coroide/tratamento farmacológico , Angiofluoresceinografia , Humanos , Injeções Intravítreas , Degeneração Macular/complicações , Degeneração Macular/diagnóstico , Degeneração Macular/tratamento farmacológico , Estudos Retrospectivos , Tomografia de Coerência Óptica , Degeneração Macular Exsudativa/diagnóstico , Degeneração Macular Exsudativa/tratamento farmacológico
19.
Brain Behav ; 11(8): e2274, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34227259

RESUMO

INTRODUCTION: Several lines of evidence suggest that the amygdala-hippocampus is involved in the epileptogenic network of juvenile myoclonic epilepsy (JME). The aim of this study was to investigate the alterations in the individual nuclei of the amygdala and hippocampal subfields, and the intrinsic amygdala-hippocampal network of patients with JME compared to healthy controls. METHODS: This retrospective study conducted at a single tertiary hospital involved 35 patients with newly diagnosed JME, and 34 healthy subjects. We calculated the individual structural volumes of 18 nuclei in the amygdala, and 38 hippocampal subfields using three-dimensional volumetric T1-weighted imaging and FreeSurfer program. We also performed an analysis of the intrinsic amygdala-hippocampal global and local network based on these volumes using a graph theory and Brain Analysis using Graph Theory (BRAPH) program. We investigated the differences in these volumes and network measures between patients with JME and healthy controls. RESULTS: There were no significant volume differences in the nuclei of the amygdala and hippocampal subfields between patients with JME and healthy controls. However, we found significant differences in the global network between patients with JME and healthy controls. The mean clustering coefficient was significantly decreased in patients with JME compared to healthy controls (0.473 vs. 0.653, p = .047). In addition, specific regions in the hippocampal subfields showed significant differences in the local network between the two groups. The betweenness centrality of the right CA1-head, right hippocampus-amygdala-transition area, left hippocampal fissure, left fimbria, and left CA3-head, was increased in patients with JME compared to healthy controls. CONCLUSION: The intrinsic amygdala-hippocampal global and local networks differed in patients with JME compared to healthy controls, which may be related to the pathogenesis of JME, and memory dysfunction in patients with JME.


Assuntos
Epilepsia Mioclônica Juvenil , Tonsila do Cerebelo/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Epilepsia Mioclônica Juvenil/diagnóstico por imagem , Estudos Retrospectivos
20.
Sci Rep ; 11(1): 15509, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34330991

RESUMO

This study aimed to quantify the Haller vessel and choriocapillaris (CC) parameters in drusen subtypes in nonexudative age-related macular degeneration (AMD) and pachydrusen. Ninety-five eyes of 80 patients and 28 control eyes were categorized into soft drusen, subretinal drusenoid deposit (SDD), soft drusen plus SDD, pachydrusen, and control groups. The diameter, length and intersections of Haller vessels and the total area, size and number of CC flow voids were quantified using en face optical coherence tomography (OCT) or OCT angiography. The pachydrusen group showed the largest Haller vessel area and diameter and shortest total length but similar CC parameters to those in the control group. The soft drusen plus SDD group showed the largest CC flow void area and size, while the Haller parameters were similar to those in the control group. The area and size of the flow voids in the SDD group were smaller than those in the soft drusen plus SDD group. Based on unsupervised machine learning, the eyes were classified into 4 clusters-the control, pachydrusen, soft drusen plus SDD and soft drusen plus SDD groups. Cluster 3 showed a larger diameter and shorter total length of the Haller vessels than cluster 4.


Assuntos
Corioide/patologia , Degeneração Macular/patologia , Drusas Retinianas/patologia , Idoso , Corioide/metabolismo , Feminino , Humanos , Degeneração Macular/metabolismo , Masculino , Pessoa de Meia-Idade , Drusas Retinianas/metabolismo , Tomografia de Coerência Óptica
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