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2.
IEEE Trans Biomed Eng ; PP2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39292577

RESUMO

OBJECTIVE: To develop an innovative deep convolutional neural network (DCNN)-based tract classification to enhance the prediction of short-term postoperative language improvement using axonal connectivity markers derived from specific language modular networks (LMNs) within the preoperative whole-brain diffusion-weighted imaging connectome (wDWIC). METHODS: We employed a three-step approach. First, our previous DCNN-based tract classification to detect true-positive eloquent tracts was extended using an open-source database of high-quality wDWIC to facilitate the accurate classification of truepositive tracts within the preoperative backbone wDWIC of individual patients. Next, we applied psychometry-driven DWIC analysis to the resulting DCNN-based backbone wDWIC in order to create core, expressive, and receptive LMNs. Finally, graph and circuit theory-based connectivity markers were assessed within the three LMNs and compared using a series of machine learning algorithms to predict the presence of postoperative language improvement from a given LMN. RESULTS: The results showed that the extended DCNN tract classification significantly improved the reproducibility of connectivity markers by up to 35.5% of F-statistics across different LMNs. The prediction accuracy increased by up to 40% across different machine learning algorithms. Notably, the best algorithm achieved the accuracy of 96%/94%/96% to predict the presence of language improvement about two months after surgery in core/expressive/receptive domain of an independent validation cohort. CONCLUSION: These domains hold great potential to assist physicians in identifying candidates whose language skills stand to benefit from early surgery. SIGNIFICANCE: DCNN tract classification may be an effective tool to improve predicting short-term postoperative language improvement in pediatric epilepsy surgery.

3.
Epilepsy Behav ; 160: 110009, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39241639

RESUMO

The "crowding" effect (CE), wherein verbal functions are preserved presumably at the expense of nonverbal functions, which diminish following inter-hemispheric transfer of language functions, is recognized as a specific aspect of functional reorganization, offering an insight about neural plasticity in children with neural insult to the dominant hemisphere. CE is hypothesized as a marker for language preservation or improvement after left-hemispheric injury, yet it remains challenging to fully discern it in preoperative evaluation. We present a novel DWI connectome (DWIC) approach to predict the presence of CE in 24 drug-resistant epilepsy (DRE) patients with a left-hemispheric focus and 29 young healthy controls. Psychometry-driven DWIC analysis was applied to create verbal and non-verbal modular networks. Local efficiency (LE) was assessed at individual regions of the two networks and its Z-score was compared to predict the presence of CE. Compared with a traditional organization (TO) group, wherein verbal functions are adversely affected, while non-verbal functions are preserved, the CE group showed significantly higher Z-scores in verbal network and significantly lower Z-scores in non-verbal network, corresponding to network reorganization in CE. A larger number of antiseizure drugs was significantly associated with more decreased Z-score in the right non-verbal network of the CE group and left verbal network of the TO group. These findings hold great potential to identify DRE patients whose verbal/language skills may over time be preserved due to effective inter-hemispheric reorganization and identify those whose verbal/language impairments may persist due to lack of inter-hemispheric reorganization.

4.
J Child Neurol ; : 8830738241272064, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39175387

RESUMO

BACKGROUND: Postcontrast magnetic resonance imaging (MRI), obtained under anesthesia, is often used to evaluate brain parenchymal and vascular abnormalities in young children, including those with Sturge-Weber syndrome. However, anesthesia and contrast administration may carry risks. We explored the feasibility and potential diagnostic value of a noncontrast, nonsedate MRI acquisition in Sturge-Weber syndrome children and their siblings with a wide range of cognitive and behavioral functioning. METHODS: Twenty children (10 with Sturge-Weber syndrome and 10 healthy siblings; age: 0.7-13.5 years) underwent nonsedate 3-tesla (T) brain MRI acquisition with noncontrast sequences (including susceptibility-weighted imaging) prospectively along with neuropsychology assessment. All images were evaluated for quality, and MRI abnormalities identified in the Sturge-Weber syndrome group were compared to those identified on previous clinical pre- and postcontrast MRI. RESULTS: Nineteen participants (95%) completed the MRI with good (n = 18) or adequate (n = 1) quality, including all children with Sturge-Weber syndrome and all 5 children ≤5 years of age. The Sturge-Weber syndrome group had lower cognitive functions than the controls, and both groups had several children with behavioral issues, without an apparent effect on the success and quality of the MR images. Susceptibility-weighted imaging detected key venous vascular abnormalities and calcifications and, along with the other noncontrast sequences, provided diagnostic information comparable to previous clinical MRI performed with contrast administration under anesthesia. CONCLUSION: This study demonstrates the feasibility and the potential diagnostic value of a nonsedate, noncontrast MRI acquisition protocol in young children including those with cognitive impairment and/or behavioral concerns. This approach can facilitate clinical trials in children where safe serial MRI is warranted.

5.
Quant Imaging Med Surg ; 14(2): 1916-1929, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38415136

RESUMO

Background: Enlarged deep medullary veins (EDMVs) in patients with Sturge-Weber syndrome (SWS) may channel venous blood from the surface to the deep vein system in brain regions affected by the leptomeningeal venous malformation. Thus, the quantification of EDMV volume may provide an objective imaging marker for this vascular compensatory process. The present study proposes a novel analytical method to quantify enlarged EDMV volumes in the affected hemisphere of patients with unilateral SWS. Methods: Twenty young subjects, including 10 patients with unilateral SWS and 10 healthy siblings (age 14.5±6.7 and 16.0±7.0 years, respectively) underwent 3T brain MRI scanning using susceptibility-weighted imaging (SWI) and volumetric T1-weighted sequences. The proposed image analytic steps segmented EDMVs in white matter regions, defined on the volumetric T1-weighted images, by statistically associating the likelihood of intensity, location, and tubular shape on SWI. The volumes of the segmented EDMVs, calculated in each hemisphere, were compared between affected and unaffected hemispheres. EDMV volumes were also correlated with visually assessed EDMV scores, hemispheric white matter volumes, and cortical surface areas. Parametric tests including Pearson's correlation, unpaired and paired t-tests, were used. A P value <0.05 was considered statistically significant. Results: It was found that EDMVs were identified well in SWS-affected hemispheres while calcified regions were excluded. Mean EDMV volumes in the SWS-affected hemispheres were 10-12-fold greater than in the unaffected or healthy control hemispheres; while white matter volumes and cortical surface areas were lower. EDMV volumes in the SWS-affected hemispheres showed a strong positive correlation with the visual EDMV scores (r=0.88, P=0.001) and an inverse correlation with cortical surface area ratios (r=-0.65, P=0.04) but no correlation with white matter volume ratios. Conclusions: EDMVs were detected in the SWS-affected atrophic hemispheres reliably while avoiding calcified regions. The approach can be used to quantify enlarged deep cerebral veins in the human brain, which may provide a potential marker of cerebral venous remodeling.

6.
Mol Imaging Biol ; 26(1): 29-35, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38012510

RESUMO

PURPOSE: Preclinical studies showed the tryptophan analog PET radiotracer 1-(2-18F-fluoroethyl)-L-tryptophan (18F-FETrp) to accumulate in various tumors, including gliomas, and being metabolized via the immunosuppressive kynurenine pathway. In this first-in-human study, we tested the use 18F-FETrp-PET in patients with neuroendocrine and brain tumors. PROCEDURES: We applied dynamic brain imaging in patients with gliomas (n = 2) and multi-pass 3D whole-body PET scans in patients with neuroendocrine tumors (n =4). Semiquantitative analysis of organ and tumor tracer uptake was performed using standardized uptake values (SUVs). In addition, organ dosimetry was performed based on extracted time-activity curves and the OLINDA software. RESULTS: Neuroendocrine tumors showed an early peak (10-min post-injection) followed by washout. Both gliomas showed prolonged 18F-FETrp accumulation plateauing around 40 min and showing heterogeneous uptake including non-enhancing tumor regions. Biodistribution showed moderate liver uptake and fast clearance of radioactivity into the urinary bladder; the estimated effective doses were similar to other 18F-labeled radioligands. CONCLUSIONS: The study provides proof-of-principle data for the safety and potential clinical value of 18F-FETrp-PET for molecular imaging of human gliomas.


Assuntos
Glioma , Tumores Neuroendócrinos , Humanos , Triptofano/metabolismo , Distribuição Tecidual , Tomografia por Emissão de Pósitrons/métodos
7.
J Labelled Comp Radiopharm ; 66(7-8): 180-188, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37118900

RESUMO

The radiotracer 1-(2-[18 F]fluoroethyl)-L-tryptophan (L-[18 F]FETrp or [18 F]FETrp) is a substrate of indoleamine 2,3-dioxygenase, the initial and key enzyme of the kynurenine pathway associated with tumoral immune resistance. In preclinical positron emission tomography studies, [18 F]FETrp is highly accumulated in a wide range of primary and metastatic cancers, such as lung cancer, prostate cancer, and gliomas. However, the clinical translation of this radiotracer into the first-in-human trial has not been reported, partially due to its racemization during radiofluorination which renders the purification of the final product challenging. However, efficient purification is essential for human studies in order to assure radiochemical and enantiomeric purity. In this work, we report a fully automated radiosynthesis of [18 F]FETrp on a Synthra RNPlus research module, including a one-pot two steps radiosynthesis, dual independent chiral and reverse-phase semipreparative high-performance liquid chromatography purifications, and solid-phase extraction-assisted formulation. The presented approach has led to its Investigational New Drug application and approval that allows the testing of this tracer in humans.


Assuntos
Neoplasias Pulmonares , Neoplasias da Próstata , Masculino , Humanos , Triptofano , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/química , Radioisótopos de Flúor/química
8.
Pediatr Neurol ; 139: 49-58, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36521316

RESUMO

BACKGROUND: Enlarged deep medullary veins (EDMVs) in patients with Sturge-Weber syndrome (SWS) may provide compensatory venous drainage for brain regions affected by the leptomeningeal venous malformation (LVM). We evaluated the prevalence, extent, hemispheric differences, and clinical correlates of EDMVs in SWS. METHODS: Fifty children (median age: 4.5 years) with unilateral SWS underwent brain magnetic resonance imaging prospectively including susceptibility-weighted imaging (SWI); children aged 2.5 years or older also had a formal neurocognitive evaluation. The extent of EDMVs was assessed on SWI by using an EDMV hemispheric score, which was compared between patients with right and left SWS and correlated with clinical variables. RESULTS: EDMVs were present in 89% (24 of 27) of right and 78% (18 of 23) of left SWS brains. Extensive EDMVs (score >6) were more frequent in right (33%) than in left SWS (9%; P = 0.046) and commonly occurred in young children with right SWS. Patients with EDMV scores >4 had rare (less than monthly) seizures, whereas 35% (11 of 31) of patients with EDMV scores ≤4 had monthly or more frequent seizures (P = 0.003). In patients with right SWS and at least two LVM-affected lobes, higher EDMV scores were associated with higher intelligence quotient (P < 0.05). CONCLUSIONS: Enlarged deep medullary veins are common in unilateral SWS, but extensive EDMVs appear to develop more commonly and earlier in right hemispheric SWS. Deep venous remodeling may be a compensatory mechanism contributing to better clinical outcomes in some patients with SWS.


Assuntos
Síndrome de Sturge-Weber , Criança , Humanos , Pré-Escolar , Síndrome de Sturge-Weber/complicações , Convulsões/complicações , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Córtex Cerebral/patologia
9.
IEEE J Biomed Health Inform ; 26(11): 5529-5539, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35925854

RESUMO

The present study investigates the effectiveness of a deep learning neural network for non-invasively localizing the seizure onset zone (SOZ) using multi-modal MRI data that are clinically acquired from children with drug-resistant epilepsy. A cortical parcellation was applied to localize the SOZ in cortical nodes of the epileptogenic hemisphere. At each node, the laminar surface analysis was followed to sample 1) the relative intensity of gray matter and white matter in multi-modal MRI and 2) the neighboring white matter connectivity using diffusion tractography edge strengths. A cross-validation was employed to train and test all layers of a multi-scale residual neural network (msResNet) that can classify SOZ node in an end-to-end fashion. A prediction probability of a given node belonging to the SOZ class was proposed as a non-invasive MRI marker of seizure onset likelihood. In an independent validation cohort, the proposed MRI marker provided a very large effect size of Cohen's d = 1.21 between SOZ and non-SOZ, and classified SOZ with a balanced accuracy of 0.75 in lesional and 0.67 in non-lesional MRI groups. The subsequent multi-variate logistic regression found the incorporation of the proposed MRI marker into interictal intracranial EEG (iEEG) markers further improves the differentiation between the epileptogenic focus (defined as SOZ resected during surgery) and non-epileptogenic sites (i.e., non-SOZ sites preserved during surgery) up to 15 % in non-lesional MRI group, suggesting that the proposed MRI marker could improve the localization of epileptogenic foci for successful pediatric epilepsy surgery.


Assuntos
Aprendizado Profundo , Epilepsia Resistente a Medicamentos , Epilepsia , Criança , Humanos , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Convulsões , Eletrocorticografia , Imageamento por Ressonância Magnética , Epilepsia/diagnóstico por imagem , Epilepsia/cirurgia , Eletroencefalografia , Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia
10.
Mol Imaging ; 2022: 5358545, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35517711

RESUMO

Introduction: Positron emission tomography (PET) imaging with prostate-specific membrane antigen- (PSMA-) binding tracers has been found incidentally to demonstrate uptake in CNS tumors. Following the encouraging findings of several such case reports, there is a growing interest in the potential application of PSMA-targeted PET imaging for diagnostics, theranostics, and monitoring of CNS tumors. This is a systematic literature review on PSMA-binding tracers in CNS tumors. Methods: A PubMed search was conducted, including preclinical and clinical reports. One hundred and twelve records were identified, and after screening, 56 were included in the final report. Results: Tissue studies demonstrated PSMA expression in tumor vascular endothelial cells, without expression in normal brain tissue, though the extent and intensity of staining varied by anti-PSMA antibody and methodology. Most included studies reported on gliomas, which showed strong PSMA ligand uptake and more favorable tumor to background ratios than other PET tracers. There are also case reports demonstrating PSMA ligand uptake in prostate cancer brain metastases, nonprostate cancer brain metastases, and meningiomas. We also review the properties of the various PSMA-binding radiotracers available. Therapeutic and theranostic applications of PSMA-binding tracers have been studied, including labeled alpha- and beta-ray emitting isotopes, as well as PSMA targeting in directing MRI-guided focused ultrasound. Conclusions: There is a potential application for PSMA-targeted PET in neuro-oncology as a combination of diagnostic and therapeutic use, as a theranostic modality for managing CNS tumors. Further research is needed regarding the mechanism(s) of PSMA expression in CNS tumors and its differential performance by tumor type.


Assuntos
Neoplasias Encefálicas , Neoplasias da Próstata , Neoplasias Encefálicas/diagnóstico por imagem , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Humanos , Ligantes , Masculino , Neuroimagem , Tomografia por Emissão de Pósitrons , Próstata , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/metabolismo , Compostos Radiofarmacêuticos
11.
Epilepsia ; 63(7): 1787-1798, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35388455

RESUMO

OBJECTIVE: To determine the structural networks that constrain propagation of ictal oscillations during epileptic spasm events, and compare the observed propagation patterns across patients with successful or unsuccessful surgical outcomes. METHODS: Subdural electrode recordings of 18 young patients (age 1-11 years) were analyzed during epileptic spasm events to determine ictal networks and quantify the amplitude and onset time of ictal oscillations across the cortical surface. Corresponding structural networks were generated with diffusion magnetic resonance imaging (MRI) tractography by seeding the cortical region associated with the earliest average oscillation onset time, and white matter pathways connecting active electrode regions within the ictal network were isolated. Properties of this structural network were used to predict oscillation onset times and amplitudes, and this relationship was compared across patients who did and did not achieve seizure freedom following resective surgery. RESULTS: Onset propagation patterns were relatively consistent across each patient's spasm events. An electrode's average ictal oscillation onset latency was most significantly associated with the length of direct corticocortical tracts connecting to the area with the earliest average oscillation onset (p < .001, model R2  = .54). Moreover, patients demonstrating a faster propagation of ictal oscillation signals within the corticocortical network were more likely to have seizure recurrence following resective surgery (p = .039). In addition, ictal oscillation amplitude was associated with connecting tractography length and weighted fractional anisotropy (FA) measures along these pathways (p = .002/.030, model R2  = .31/.25). Characteristics of analogous corticothalamic pathways did not show significant associations with ictal oscillation onset latency or amplitude. SIGNIFICANCE: Spatiotemporal propagation patterns of high-frequency activity in epileptic spasms align with length and FA measures from onset-originating corticocortical pathways. Considering the data in this individualized framework may help inform surgical decision-making and expectations of surgical outcomes.


Assuntos
Eletroencefalografia , Espasmos Infantis , Criança , Pré-Escolar , Imagem de Tensor de Difusão , Eletroencefalografia/métodos , Humanos , Lactente , Convulsões/cirurgia , Espasmo , Espasmos Infantis/diagnóstico por imagem , Espasmos Infantis/cirurgia
14.
Mol Imaging ; 2021: 8874078, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194287

RESUMO

Introduction: Standard neuroimaging protocols for brain tumors have well-known limitations. The clinical use of additional modalities including amino acid PET (aaPET) and advanced MRI (aMRI) techniques (including DWI, PWI, and MRS) is emerging in response to the need for more accurate detection of brain tumors. In this systematic review of the past 2 years of the literature, we discuss the most recent studies that directly compare or combine aaPET and aMRI for brain tumor imaging. Methods: A PubMed search was conducted for human studies incorporating both aaPET and aMRI and published between July 2018 and August 2020. Results: A total of 22 studies were found in the study period. Recent studies of aaPET with DWI showed a superiority of MET, FET, FDOPA, and AMT PET for detecting tumor, predicting recurrence, diagnosing progression, and predicting survival. Combining modalities further improved performance. Comparisons of aaPET with PWI showed mixed results about spatial correlation. However, both modalities were able to detect high-grade tumors, identify tumor recurrence, differentiate recurrence from treatment effects, and predict survival. aaPET performed better on these measures than PWI, but when combined, they had the strongest results. Studies of aaPET with MRS demonstrated that both modalities have diagnostic potential but MET PET and FDOPA PET performed better than MRS. MRS suffered from some data quality issues that limited analysis in two studies, and, in one study that combined modalities, overall performance actually decreased. Four recent studies compared aaPET with emerging MRI approaches (such as CEST imaging, MR fingerprinting, and SISTINA), but the initial results remain inconclusive. Conclusions: aaPET outperformed the aMRI imaging techniques in most recent studies. DWI and PWI added meaningful complementary data, and the combination of aaPET with aMRI yielded the best results in most studies.


Assuntos
Aminoácidos , Neoplasias Encefálicas , Neoplasias Encefálicas/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neuroimagem , Tomografia por Emissão de Pósitrons
15.
Epilepsy Behav ; 122: 108185, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34252829

RESUMO

OBJECTIVE: Abnormalities of brain structures and neuronal networks have been identified in MRI studies of patients with Sudden Unexpected Death in Epilepsy (SUDEP) as well as in those at elevated risk. The goal of this study was to identify common patterns of objectively detected brain glucose metabolic abnormalities associated with SUDEP patients and those at high SUDEP risk. METHODS: Patients with refractory epilepsy (n = 78, age: 16-61 years, 44 females), who underwent comprehensive presurgical evaluation, were assessed for their risk of SUDEP using the revised SUDEP-7 inventory. From the 57 patients with low SUDEP risk, 35 were selected to match their demographic and clinical characteristics to those with high SUDEP risk (n = 21). [18F]fluoro-deoxy-glucose positron emission tomography (FDG-PET) abnormalities were evaluated in the high- and low-SUDEP risk subgroups compared to FDG-PET scans of a healthy adult control group using statistical parametric mapping (SPM). Individual FDG-PET scans of 4 additional patients, who died from SUDEP, were also analyzed by SPM. RESULTS: Mean SUDEP-7 score was 6.1 in the high and 2.7 in the low SUDEP risk group. MRI showed no lesion in 36 patients (64%). Statistical parametric mapping analysis of the high SUDEP risk subgroup showed bilateral medial frontal and inferior frontal hypometabolism as a common pattern. The low-risk group showed no specific common metabolic abnormalities on SPM group analysis. Individual PET scans of all 4 patients who died from SUDEP also showed bilateral frontal lobe hypometabolism. CONCLUSIONS: These data show that bilateral frontal lobe involvement on FDG-PET, especially the medial and inferior frontal cortex, may be a common metabolic pattern associated with high SUDEP risk and SUDEP itself, in patients with refractory focal epilepsy.


Assuntos
Morte Súbita Inesperada na Epilepsia , Adolescente , Adulto , Feminino , Fluordesoxiglucose F18 , Lobo Frontal , Objetivos , Humanos , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto Jovem
16.
Pediatr Neurol ; 121: 59-66, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34153815

RESUMO

BACKGROUND: Sturge-Weber syndrome (SWS) is a sporadic, neurocutaneous syndrome involving the skin, brain, and eyes. Because of the variability of the clinical manifestations and the lack of prospective studies, consensus recommendations for management and treatment of SWS have not been published. OBJECTIVE: This article consolidates the current literature with expert opinion to make recommendations to guide the neuroimaging evaluation and the management of the neurological and ophthalmologic features of SWS. METHODS: Thirteen national peer-recognized experts in neurology, radiology, and ophthalmology with experience treating patients with SWS were assembled. Key topics and questions were formulated for each group and included (1) risk stratification, (2) indications for referral, and (3) optimum treatment strategies. An extensive PubMed search was performed of English language articles published in 2008 to 2018, as well as recent studies identified by the expert panel. The panel made clinical practice recommendations. CONCLUSIONS: Children with a high-risk facial port-wine birthmark (PWB) should be referred to a pediatric neurologist and a pediatric ophthalmologist for baseline evaluation and periodic follow-up. In newborns and infants with a high-risk PWB and no history of seizures or neurological symptoms, routine screening for brain involvement is not recommended, but brain imaging can be performed in select cases. Routine follow-up neuroimaging is not recommended in children with SWS and stable neurocognitive symptoms. The treatment of ophthalmologic complications, such as glaucoma, differs based on the age and clinical presentation of the patient. These recommendations will help facilitate coordinated care for patients with SWS and may improve patient outcomes.


Assuntos
Consenso , Guias de Prática Clínica como Assunto/normas , Síndrome de Sturge-Weber/diagnóstico , Síndrome de Sturge-Weber/terapia , Criança , Pré-Escolar , Congressos como Assunto , Glaucoma/diagnóstico , Glaucoma/etiologia , Glaucoma/terapia , Humanos , Lactente , Recém-Nascido , Neuroimagem/normas , Neurologia/normas , Oftalmologia/normas , Mancha Vinho do Porto/diagnóstico , Mancha Vinho do Porto/etiologia , Mancha Vinho do Porto/terapia , Convulsões/diagnóstico , Convulsões/etiologia , Convulsões/terapia , Síndrome de Sturge-Weber/complicações
17.
Plants (Basel) ; 10(5)2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34069010

RESUMO

Woolly cupgrass (Eriochloa villosa (Thunb.) Kunth) is a new invasive weed in Hungary. This study was conducted to elucidate the effects of this weed on the biochemistry and growth of maize (Zea mays L. cv. Armagnac) under greenhouse conditions. Activities of the antioxidative enzymes (ascorbate peroxidase (APX), guaiacol peroxidase (POD), superoxide dismutase (SOD)), the contents of malondialdehyde (MDA), and protein were measured in the shoots and roots, whereas the content of the photosynthetic pigments was measured only in the shoots. The measured growth parameters included plant height, root length, root volume, root and shoot dry weight, and stem diameter. Results showed the allelopathic effects of woolly cupgrass on maize, with significant decreases in plant height, root length, root volume, and root dry weight. Woolly cupgrass infestation (WCI) induced significantly higher activities of APX and SOD in the shoots, whereas POD was only induced in the roots. The contents of chlorophyll-a, total chlorophyll (including relative chlorophyll), carotenoids, and root protein were substantially reduced by WCI, except for the leaf chlorophyll-b. The results suggest that high APX and SOD activities in the shoots could be involved in stabilizing the leaf chlorophyll-b, chlorophyll a/b, shoot protein, and shoot dry weight because all of these parameters were not inhibited when these two enzymes were induced. In contrast, high activity of POD in the roots is not effective in counteracting allelopathy. Therefore, it would be worthwhile to further investigate if an increase in the activities of APX and SOD in the shoots of WCI maize is responsible for stabilizing leaf chlorophyll-b, shoot protein, and shoot dry weight, which could contribute to improved maize yield under WCI.

18.
Hum Brain Mapp ; 42(10): 3326-3338, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33949048

RESUMO

This study investigated whether current state-of-the-art deep reasoning network analysis on psychometry-driven diffusion tractography connectome can accurately predict expressive and receptive language scores in a cohort of young children with persistent language concerns (n = 31, age: 4.25 ± 2.38 years). A dilated convolutional neural network combined with a relational network (dilated CNN + RN) was trained to reason the nonlinear relationship between "dilated CNN features of language network" and "clinically acquired language score". Three-fold cross-validation was then used to compare the Pearson correlation and mean absolute error (MAE) between dilated CNN + RN-predicted and actual language scores. The dilated CNN + RN outperformed other methods providing the most significant correlation between predicted and actual scores (i.e., Pearson's R/p-value: 1.00/<.001 and .99/<.001 for expressive and receptive language scores, respectively) and yielding MAE: 0.28 and 0.28 for the same scores. The strength of the relationship suggests elevated probability in the prediction of both expressive and receptive language scores (i.e., 1.00 and 1.00, respectively). Specifically, sparse connectivity not only within the right precentral gyrus but also involving the right caudate had the strongest relationship between deficit in both the expressive and receptive language domains. Subsequent subgroup analyses inferred that the effectiveness of the dilated CNN + RN-based prediction of language score(s) was independent of time interval (between MRI and language assessment) and age of MRI, suggesting that the dilated CNN + RN using psychometry-driven diffusion tractography connectome may be useful for prediction of the presence of language disorder, and possibly provide a better understanding of the neurological mechanisms of language deficits in young children.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Aprendizado Profundo , Imagem de Tensor de Difusão , Transtornos da Linguagem/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Adolescente , Córtex Cerebral/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Transtornos da Linguagem/patologia , Transtornos da Linguagem/fisiopatologia , Masculino , Rede Nervosa/patologia , Psicometria
19.
Pediatr Neurol ; 119: 3-10, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33813331

RESUMO

BACKGROUND: Epilepsy in typical Sturge-Weber syndrome (SWS) is common, and many questions remain regarding the treatment outcomes. We analyzed a large multicenter database with focus on neurological drug treatment in different demographic and SWS characteristic groups. METHODS: A total of 268 patients with brain involvement and a history of seizures were selected from a research data registry generated from a multicenter cross-sectional questionnaire. We examined associations between medication use and binary variables such as sex, ethnicity, and brain, skin, and eye involvement laterality. We analyzed group differences in mean number of antiseizure medications and age at diagnosis, enrollment, and seizure onset and examined differences in median SWS neurological scores in groups of interest. RESULTS: The most frequently used medications were levetiracetam (48.1%), low-dose aspirin (44.8%), oxcarbazepine (39.9%), and phenobarbital (14.9%). Lamotrigine was more frequently used in adults than in children (P = 0.001). History of neurosurgery was associated with no current antiseizure medication use (P = 0.001), whereas bilateral brain involvement and family history of seizures were associated with using a higher number of antiseizure medications (P = 0.002, P = 0.027, respectively). Subjects with bilateral brain involvement and early seizure onset were associated with using a higher number of antiseizure medications (P = 0.002) and phenobarbital use (0.003). CONCLUSIONS: Levetiracetam, low-dose aspirin, and oxcarbazepine were the most frequently used medications. More severely affected patients were frequently on a greater number of antiseizure medications. Surgery for epilepsy was associated with the ability to discontinue antiseizure medication. Longitudinal studies are needed to further investigate medication use in patients with SWS.


Assuntos
Anticonvulsivantes/farmacologia , Epilepsia/tratamento farmacológico , Epilepsia/etiologia , Epilepsia/cirurgia , Síndrome de Sturge-Weber/complicações , Adolescente , Adulto , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Procedimentos Neurocirúrgicos , Avaliação de Resultados em Cuidados de Saúde , Adulto Jovem
20.
Epilepsy Behav ; 117: 107909, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33740493

RESUMO

PURPOSE: Focal epilepsy is a risk factor for language impairment in children. We investigated whether the current state-of-the-art deep learning network on diffusion tractography connectome can accurately predict expressive and receptive language scores of children with epilepsy. METHODS: We studied 37 children with a diagnosis of drug-resistant focal epilepsy (age: 11.8 ±â€¯3.1 years) using 3 T MRI and diffusion tractography connectome: G = (S, Ω), where S is an adjacency matrix of edges representing the connectivity strength (number of white-matter tract streamlines) between each pair of brain regions, and Ω reflects a set of brain regions. A convolutional neural network (CNN) was trained to learn the nonlinear relationship between 'S (input)' and 'language score (output)'. Repeated hold-out validation was then employed to measure the Pearson correlation and mean absolute error (MAE) between CNN-predicted and actual language scores. RESULTS: We found that CNN-predicted and actual scores were significantly correlated (i.e., Pearson's R/p-value: 0.82/<0.001 and 0.75/<0.001), yielding MAE: 7.77 and 7.40 for expressive and receptive scores, respectively. Specifically, sparse connectivity not only within the left cortico-cortical network but also involving the right subcortical structures was predictive of language impairment of expressive or receptive domain. Subsequent subgroup analyses inferred that the effectiveness of diffusion tractography-based prediction of language outcome was independent of clinical variables. Intrinsic diffusion tractography connectome properties may be useful for predicting the severity of baseline language dysfunction and possibly provide a better understanding of the biological mechanisms of epilepsy-related language impairment in children.


Assuntos
Conectoma , Aprendizado Profundo , Epilepsias Parciais , Substância Branca , Adolescente , Encéfalo/diagnóstico por imagem , Criança , Imagem de Tensor de Difusão , Epilepsias Parciais/diagnóstico por imagem , Humanos , Substância Branca/diagnóstico por imagem
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