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Neuro-degeneration profile of Alzheimer's patients: A brain morphometry study

Silvio Ramos Bernardes da Silva Filho, Jeam Haroldo Oliveira Barbosa, Carlo Rondinoni, Antonio Carlos dos Santos, Carlos Ernesto Garrido Salmon, Nereida Kilza da Costa Lima, Eduardo Ferriolli, Júlio César Moriguti
2017 NeuroImage: Clinical  
Alzheimer's disease (AD) is a primary and progressive neurodegenerative disorder, which is marked by cognitive deterioration and memory impairment. Atrophy of hippocampus and other basal brain regions is one of the most predominant structural imaging findings related to AD. Most studies have evaluated the preclinical and initial stages of AD through clinical trials using Magnetic Resonance Imaging. Structural biomarkers for advanced AD stages have not been evaluated yet, being considered only
more » ... pothetically. Objective: To evaluate the brain morphometry of AD patients at all disease stages, identifying the structural neuro-degeneration profile associated with AD severity. Material and methods: AD patients aged 60 years or over at different AD stages were recruited and grouped into three groups following the Clinical Dementia Rating (CDR) score: CDR1 (n = 16), CDR2 (n = 15), CDR3 (n = 13). Age paired healthy volunteers (n = 16) were also recruited (control group). Brain images were acquired on a 3T magnetic resonance scanner using a conventional Gradient eco 3D T1-w sequence without contrast injection. Volumetric quantitative data and cortical thickness were obtained by automatic segmentation using the Freesurfer software. Volume of each brain region was normalized by the whole brain volume in order to minimize age and body size effects. Volume and cortical thickness variations among groups were compared. Results: Atrophy was observed in the hippocampus, amygdala, entorhinal cortex, parahippocampal region, temporal pole and temporal lobe of patients suffering from AD at any stage. Cortical thickness was reduced only in the parahippocampal gyrus at all disease stages. Volume and cortical thickness were correlated with the Mini Mental State Examination (MMSE) score in all studied regions, as well as with CDR and disease duration. Discussion and conclusion: As previously reported, brain regions affected by AD during its initial stages, such as hippocampus, amygdala, entorhinal cortex, and parahippocampal region, were found to be altered even in individuals with severe AD. In addition, individuals, specifically, with CDR 3, have multiple regions with lower volumes than individuals with a CDR 2. These results indicate that rates of atrophy have not plateaued out at CDR 2-3, and in severe patients there are yet neuronal loss and gliosis. These findings can add important information to the more accepted model in the literature that focuses mainly on early stages. Our findings allow a better understanding on the AD pathophysiologic process and follow-up process of drug treatment even at advanced disease stages.
doi:10.1016/j.nicl.2017.04.001 pmid:28459000 pmcid:PMC5397580 fatcat:fhu3pe7k3jhwvjfrl34qscpkey

Computer-assisted craniometric evaluation for diagnosis and follow-up of craniofacial asymmetries: SymMetric v. 1.0 [article]

Eduardo Joaquim Lopes Alho, Carlo Rondinoni, Fabio A O Furokawa, Bernardo A Monaco
2019 medRxiv   pre-print
Purpose: The current assessment of patients with craniofacial asymmetries is accomplished by physical examination, anamnesis and radiological imaging. We propose a semi-automated, computer-assisted craniofacial evaluation (SymMetric v 1.0) based on orthogonal photography of the patient's head in 3 positions. The system is simple, low-cost, no-radiation or special resources needed. Although it does not substitute CT in cases of doubt between craniosynostosis and positional plagiocephaly,
more » ... numeric evaluations indicate regional deformities and severity of the asymmetry, which can help in the clinical decision of indicating or not the orthosis in positional deformities, determining treatment duration or evaluating surgical outcomes after correction. Methods: A Matlab-based tool was developed for digital processing of photographs taken in 3 positions (anterior, superior and lateral). The software guides the user to select visible and reproducible landmarks in each photograph acquisition and calculates multiple indexes and metrics, generating a set of comprehensive plots to offer the user an overview of head and facial symmetry across the orthogonal views. For purposes of demonstration, we evaluated 2 patients (one control and one with non-sinostotic deformity). Results: The results show a clear differentiation of the control and plagiocephalic patient metrics mainly in the superior view, showing potential for diagnosis of the condition, and also detected the clinical improvement during helmet treatment in the follow-up, 3 and 5 months after orthosis use. Conclusion: We presented a proof-of-concept for a low cost, no radiation evaluation system for craniofacial asymmetries, that can be useful in a clinical context for diagnosis and follow-up of patients.
doi:10.1101/19007054 fatcat:zziyogolsrgdzfr66ymw35frby

Using network dynamic fMRI for detection of epileptogenic foci

Sanja Nedic, Steven M. Stufflebeam, Carlo Rondinoni, Tonicarlo R. Velasco, Antonio C. dos Santos, Joao P. Leite, Ana C. Gargaro, Lilianne R. Mujica-Parodi, Jaime S. Ide
2015 BMC Neurology  
Epilepsy is one of the most prevalent neurological disorders. It remains medically intractable for about one-third of patients with focal epilepsy, for whom precise localization of the epileptogenic zone responsible for seizure initiation may be critical for successful surgery. Existing fMRI literature points to widespread network disturbances in functional connectivity. Per previous scalp and intracranial EEG studies and consistent with excessive local synchronization during interictal
more » ... es, we hypothesized that, relative to same regions in healthy controls, epileptogenic foci would exhibit less chaotic dynamics, identifiable via entropic analyses of resting state fMRI time series. Methods: In order to first validate this hypothesis on a cohort of patients with known ground truth, here we test individuals with well-defined epileptogenic foci (left mesial temporal lobe epilepsy). We analyzed voxel-wise resting-state fMRI time-series using the autocorrelation function (ACF), an entropic measure of regulation and feedback, and performed follow-up seed-to-voxel functional connectivity analysis. Disruptions in connectivity of the region exhibiting abnormal dynamics were examined in relation to duration of epilepsy and patients' cognitive performance using a delayed verbal memory recall task. Results: ACF analysis revealed constrained (less chaotic) functional dynamics in left temporal lobe epilepsy patients, primarily localized to ipsilateral temporal pole, proximal to presumed focal points. Autocorrelation decay rates differentiated, with 100 % accuracy, between patients and healthy controls on a subject-by-subject basis within a leave-one-subject out classification framework. Regions identified via ACF analysis formed a less efficient network in patients, as compared to controls. Constrained dynamics were linked with locally increased and long-range decreased connectivity that, in turn, correlated significantly with impaired memory (local left temporal connectivity) and epilepsy duration (left temporalposterior cingulate cortex connectivity). Conclusions: Our current results suggest that data driven functional MRI methods that target network dynamics hold promise in providing clinically valuable tools for identification of epileptic regions.
doi:10.1186/s12883-015-0514-y pmid:26689596 pmcid:PMC4687299 fatcat:gufgqahegbgh7akiteg5ciker4

Behavioral and neuroimaging responses induced by mental imagery of threatening scenarios

Rosana Shuhama, Carlo Rondinoni, Draulio Barros de Araujo, Gustavo de Freitas Caetano, Antonio Carlos dos Santos, Frederico Guilherme Graeff, Cristina Marta Del-Ben
2016 Behavioural Brain Research  
Using Monte Carlo simulation (500 iterations), the plugin estimates the rate for false-discovery (FDR), defining a minimum cluster-size necessary to produce an effective alpha smaller than 5%.  ... 
doi:10.1016/j.bbr.2016.06.059 pmid:27452804 fatcat:6eph4vazyjbyzafz5cb3fbcvym

Patient-specific neurosurgical phantom: assessment of visual quality, accuracy, and scaling effects

Felipe Wilker Grillo, Victor Hugo Souza, Renan Hiroshi Matsuda, Carlo Rondinoni, Theo Zeferino Pavan, Oswaldo Baffa, Helio Rubens Machado, Antonio Adilton Oliveira Carneiro
2018 3D Printing in Medicine  
Alexandre Colello Bruno for intellectual contribution, Agnelo Bastos, Clésio Fernandes, Carlos Renato, Lourenço Rocha and Sérgio Bueno for technical support.  ... 
doi:10.1186/s41205-018-0025-8 pmid:29782617 pmcid:PMC5954795 fatcat:t2ykrgjcdrcmdnfwrscwfpunuy

Prospective motion correction of fMRI: Improving the quality of resting state data affected by large head motion

Danilo Maziero, Carlo Rondinoni, Theo Marins, Victor Andrew Stenger, Thomas Ernst
2020 NeuroImage  
The quality of functional MRI (fMRI) data is affected by head motion. It has been shown that fMRI data quality can be improved by prospectively updating the gradients and radio-frequency pulses in response to head motion during image acquisition by using an MR-compatible optical tracking system (prospective motion correction, or PMC). Recent studies showed that PMC improves the temporal Signal to Noise Ratio (tSNR) of resting state fMRI data (rs-fMRI) acquired from subjects not moving
more » ... lly. Besides that, the time courses of Independent Components (ICs), resulting from Independent Component Analysis (ICA), were found to present significant temporal correlation with the motion parameters recorded by the camera. However, the benefits of applying PMC for improving the quality of rs-fMRI acquired under large head movements and its effects on resting state networks (RSN) and connectivity matrices are still unknown. In this study, subjects were instructed to cross their legs at will while rs-fMRI data with and without PMC were acquired, which generated head motion velocities ranging from 4 to 30 ​mm/s. We also acquired fMRI data without intentional motion. Independent component analysis of rs-fMRI was performed to evaluate IC maps and time courses of RSNs. We also calculated the temporal correlation among different brain regions and generated connectivity matrices for the different motion and PMC conditions. In our results we verified that the crossing leg movements reduced the tSNR of sessions without and with PMC by 45 and 20%, respectively, when compared to sessions without intentional movements. We have verified an interaction between head motion speed and PMC status, showing stronger attenuation of tSNR for acquisitions without PMC than for those with PMC. Additionally, the spatial definition of major RSNs, such as default mode, visual, left and right central executive networks, was improved when PMC was enabled. Furthermore, motion altered IC-time courses by decreasing power at low frequencies and increasing power at higher frequencies (typically associated with artefacts). PMC partially reversed these alterations of the power spectra. Finally, we showed that PMC provides temporal correlation matrices for data acquired under motion conditions more comparable to those obtained by fMRI sessions where subjects were instructed not to move.
doi:10.1016/j.neuroimage.2020.116594 pmid:32044436 pmcid:PMC7238750 fatcat:ylssllmi2zhglpyvogej3ssqie

Fractional Anisotropy of Thalamic Nuclei Is Associated With Verticality Misperception After Extra-Thalamic Stroke

Taiza E. G. Santos, Jussara A. O. Baggio, Carlo Rondinoni, Laura Machado, Karina T. Weber, Luiz H. Stefano, Antonio C. Santos, Octavio M. Pontes-Neto, Joao P. Leite, Dylan J. Edwards
2019 Frontiers in Neurology  
Copyright © 2019 Santos, Baggio, Rondinoni, Machado, Weber, Stefano, Santos, Pontes-Neto, Leite and Edwards.  ... 
doi:10.3389/fneur.2019.00697 pmid:31379702 pmcid:PMC6650785 fatcat:3dqrrtvl2vflrbqkbz7dnwz5jy

Chronic Tinnitus Exhibits Bidirectional Functional Dysconnectivity in Frontostriatal Circuit

Jin-Jing Xu, Jinluan Cui, Yuan Feng, Wei Yong, Huiyou Chen, Yu-Chen Chen, Xindao Yin, Yuanqing Wu
2019 Frontiers in Neuroscience  
Finally, the auditory pathway is likely to be activated by scanner noise, which is nearly impossible to completely eliminate even with earplugs or active noise reduction (Rondinoni et al., 2013) .  ...  The voxel-wise results for group differences were corrected for multiple comparisons using 3dClustSim 3 determined by Monte Carlo simulation.  ... 
doi:10.3389/fnins.2019.01299 pmid:31866810 pmcid:PMC6909243 fatcat:brexgdd7szepvdehmvmme7u64i

Alterations in Regional Homogeneity in Patients With Unilateral Chronic Tinnitus

Anthony Gentil, Jeremy Deverdun, Nicolas Menjot de Champfleur, Jean-Luc Puel, Emmanuelle Le Bars, Frédéric Venail
2019 Trends in Hearing  
Although most investigators consider a resting-state fMRI experiment to be devoid of external stimulation, subjects are unavoidably under heavy acoustic noise produced by the equipment (Rondinoni et al  ...  A correction for multiple comparisons was performed by a Monte Carlo simulation using the AlphaSim program ( doc/manual/AlphaSim.pdf), resulting in a corrected threshold  ... 
doi:10.1177/2331216519830237 fatcat:g2cwerq6tvbhrpackdr3fe4kbe

Diverse traits of aquatic plants cannot individually explain their consumption by the generalist gastropod Biomphalairia glabrata

Renato Crespo Pereira, Nathália Nocchi, Tatiana U.P. Konno, Angelica R. Soares
2021 PeerJ  
., 1975) and the flavonoids from X. itatiayensis, X. longiscapa and X. obtusiuscula (Varanda, Rondinoni & dos Santos, 2002) .  ...  Fundação Carlos Chagas de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ). Programa Institucional de Bolsas de Iniciação Científica (PIBIC).  ... 
doi:10.7717/peerj.12031 pmid:34616600 pmcid:PMC8459730 fatcat:n4ixfc57ijevbek4q6aten37y4


Matheus Teixeira Seixas e Silva
2020 A Subsistência da Medicina Veterinária e sua Preservação  
inúmeras situações que ele enfrenta no seu convívio com a sociedade humana (RONDINONI, 2008).  ...  ValenteUniversidade Federal de Viçosa Viçosa -MG Kelvin Oliveira Rocha Universidade Federal de Viçosa Viçosa -MG Emily Correna Carlo  ... 
doi:10.22533/at.ed.84920261016 fatcat:wknh4jd5ofhxbav7u3lehcspm4

The intrinsic network architecture of the aging brain : how does it relate to cognition and behavior?

Angela M Müller
While it has been shown that scanner noise influences the temporal coupling between different ICNs (Rondinoni, Amaro, Cendres, dos Santos, & Salmon, 2013) , the effect of the eyes open/eyes closed condition  ...  In a second step, we then assessed the non-randomness of the empirical distributions of our sample by using the non-parametric two samples Kolmogorov-Smirnov test combined with the Monte Carlo method to  ... 
doi:10.5167/uzh-127611 fatcat:xhd6xho7sfarfewnu2neob66qu