160 results on '"Tavakol S"'
Search Results
2. Pathogenicity of Clinostomum complanatum (Digenea: Clinostomidae) in piscivorous birds
- Author
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Shamsi, S., Halajian, A., Tavakol, S., Mortazavi, P., and Boulton, J.
- Published
- 2013
- Full Text
- View/download PDF
3. Topographic divergence of atypical cortical asymmetry and atrophy patterns in temporal lobe epilepsy
- Author
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Park, B.-y., Larivière, S., Rodríguez-Cruces, R., Royer, J., Tavakol, S., Wang, Y., Caciagli, L., Caligiuri, M.E., Gambardella, A., Concha, L., Keller, S.S., Cendes, F., Alvim, M.K.M., Yasuda, C., Bonilha, L., Gleichgerrcht, E., Focke, N.K., Kreilkamp, B.A.K., Domin, M., Podewils, F. von, Langner, S., Rummel, C., Rebsamen, M., Wiest, R., Martin, P., Kotikalapudi, R., Bender, B., O’Brien, T.J., Law, M., Sinclair, B., Vivash, L., Kwan, P., Desmond, P.M., Malpas, C.B., Lui, E., Alhusaini, S., Doherty, C.P., Cavalleri, G.L., Delanty, N., Kälviäinen, R., Jackson, G.D., Kowalczyk, M., Mascalchi, M., Semmelroch, M., Thomas, R.H., Soltanian-Zadeh, H., Davoodi-Bojd, E., Zhang, J., Lenge, M., Guerrini, R., Bartolini, E., Hamandi, K., Foley, S., Weber, B., Depondt, C., Absil, J., Carr, S.J.A., Abela, E., Richardson, M.P., Devinsky, O., Severino, M., Striano, P., Parodi, C., Tortora, D., Hatton, S.N., Vos, S.B., Duncan, J.S., Galovic, M., Whelan, C.D., Bargalló, N., Pariente, J., Conde-Blanco, E., Vaudano, A.E., Tondelli, M., Meletti, S., Kong, X.Z., Francks, C., Fisher, S.E., Caldairou, B., Ryten, M., Labate, A., Sisodiya, S.M., Thompson, P.M., McDonald, C.R., Bernasconi, A., Bernasconi, N., Bernhardt, B.C., Park, B.-y., Larivière, S., Rodríguez-Cruces, R., Royer, J., Tavakol, S., Wang, Y., Caciagli, L., Caligiuri, M.E., Gambardella, A., Concha, L., Keller, S.S., Cendes, F., Alvim, M.K.M., Yasuda, C., Bonilha, L., Gleichgerrcht, E., Focke, N.K., Kreilkamp, B.A.K., Domin, M., Podewils, F. von, Langner, S., Rummel, C., Rebsamen, M., Wiest, R., Martin, P., Kotikalapudi, R., Bender, B., O’Brien, T.J., Law, M., Sinclair, B., Vivash, L., Kwan, P., Desmond, P.M., Malpas, C.B., Lui, E., Alhusaini, S., Doherty, C.P., Cavalleri, G.L., Delanty, N., Kälviäinen, R., Jackson, G.D., Kowalczyk, M., Mascalchi, M., Semmelroch, M., Thomas, R.H., Soltanian-Zadeh, H., Davoodi-Bojd, E., Zhang, J., Lenge, M., Guerrini, R., Bartolini, E., Hamandi, K., Foley, S., Weber, B., Depondt, C., Absil, J., Carr, S.J.A., Abela, E., Richardson, M.P., Devinsky, O., Severino, M., Striano, P., Parodi, C., Tortora, D., Hatton, S.N., Vos, S.B., Duncan, J.S., Galovic, M., Whelan, C.D., Bargalló, N., Pariente, J., Conde-Blanco, E., Vaudano, A.E., Tondelli, M., Meletti, S., Kong, X.Z., Francks, C., Fisher, S.E., Caldairou, B., Ryten, M., Labate, A., Sisodiya, S.M., Thompson, P.M., McDonald, C.R., Bernasconi, A., Bernasconi, N., and Bernhardt, B.C.
- Abstract
Contains fulltext : 252489.pdf (Publisher’s version ) (Open Access)
- Published
- 2022
4. Topographic divergence of atypical cortical asymmetry and atrophy patterns in temporal lobe epilepsy
- Author
-
Park, B-Y, Lariviere, S, Rodriguez-Cruces, R, Royer, J, Tavakol, S, Wang, Y, Caciagli, L, Caligiuri, ME, Gambardella, A, Concha, L, Keller, SS, Cendes, F, Alvim, MKM, Yasuda, C, Bonilha, L, Gleichgerrcht, E, Focke, NK, Kreilkamp, BAK, Domin, M, von Podewils, F, Langner, S, Rummel, C, Rebsamen, M, Wiest, R, Martin, P, Kotikalapudi, R, Bender, B, O'Brien, TJ, Law, M, Sinclair, B, Vivash, L, Kwan, P, Desmond, PM, Malpas, CB, Lui, E, Alhusaini, S, Doherty, CP, Cavalleri, GL, Delanty, N, Kalviainen, R, Jackson, GD, Kowalczyk, M, Mascalchi, M, Semmelroch, M, Thomas, RH, Soltanian-Zadeh, H, Davoodi-Bojd, E, Zhang, J, Lenge, M, Guerrini, R, Bartolini, E, Hamandi, K, Foley, S, Weber, B, Depondt, C, Absil, J, Carr, SJA, Abela, E, Richardson, MP, Devinsky, O, Severino, M, Striano, P, Parodi, C, Tortora, D, Hatton, SN, Vos, SB, Duncan, JS, Galovic, M, Whelan, CD, Bargallo, N, Pariente, J, Conde-Blanco, E, Vaudano, AE, Tondelli, M, Meletti, S, Kong, X-Z, Francks, C, Fisher, SE, Caldairou, B, Ryten, M, Labate, A, Sisodiya, SM, Thompson, PM, McDonald, CR, Bernasconi, A, Bernasconi, N, Bernhardt, BC, Park, B-Y, Lariviere, S, Rodriguez-Cruces, R, Royer, J, Tavakol, S, Wang, Y, Caciagli, L, Caligiuri, ME, Gambardella, A, Concha, L, Keller, SS, Cendes, F, Alvim, MKM, Yasuda, C, Bonilha, L, Gleichgerrcht, E, Focke, NK, Kreilkamp, BAK, Domin, M, von Podewils, F, Langner, S, Rummel, C, Rebsamen, M, Wiest, R, Martin, P, Kotikalapudi, R, Bender, B, O'Brien, TJ, Law, M, Sinclair, B, Vivash, L, Kwan, P, Desmond, PM, Malpas, CB, Lui, E, Alhusaini, S, Doherty, CP, Cavalleri, GL, Delanty, N, Kalviainen, R, Jackson, GD, Kowalczyk, M, Mascalchi, M, Semmelroch, M, Thomas, RH, Soltanian-Zadeh, H, Davoodi-Bojd, E, Zhang, J, Lenge, M, Guerrini, R, Bartolini, E, Hamandi, K, Foley, S, Weber, B, Depondt, C, Absil, J, Carr, SJA, Abela, E, Richardson, MP, Devinsky, O, Severino, M, Striano, P, Parodi, C, Tortora, D, Hatton, SN, Vos, SB, Duncan, JS, Galovic, M, Whelan, CD, Bargallo, N, Pariente, J, Conde-Blanco, E, Vaudano, AE, Tondelli, M, Meletti, S, Kong, X-Z, Francks, C, Fisher, SE, Caldairou, B, Ryten, M, Labate, A, Sisodiya, SM, Thompson, PM, McDonald, CR, Bernasconi, A, Bernasconi, N, and Bernhardt, BC
- Abstract
Temporal lobe epilepsy, a common drug-resistant epilepsy in adults, is primarily a limbic network disorder associated with predominant unilateral hippocampal pathology. Structural MRI has provided an in vivo window into whole-brain grey matter structural alterations in temporal lobe epilepsy relative to controls, by either mapping (i) atypical inter-hemispheric asymmetry; or (ii) regional atrophy. However, similarities and differences of both atypical asymmetry and regional atrophy measures have not been systematically investigated. Here, we addressed this gap using the multisite ENIGMA-Epilepsy dataset comprising MRI brain morphological measures in 732 temporal lobe epilepsy patients and 1418 healthy controls. We compared spatial distributions of grey matter asymmetry and atrophy in temporal lobe epilepsy, contextualized their topographies relative to spatial gradients in cortical microstructure and functional connectivity calculated using 207 healthy controls obtained from Human Connectome Project and an independent dataset containing 23 temporal lobe epilepsy patients and 53 healthy controls and examined clinical associations using machine learning. We identified a marked divergence in the spatial distribution of atypical inter-hemispheric asymmetry and regional atrophy mapping. The former revealed a temporo-limbic disease signature while the latter showed diffuse and bilateral patterns. Our findings were robust across individual sites and patients. Cortical atrophy was significantly correlated with disease duration and age at seizure onset, while degrees of asymmetry did not show a significant relationship to these clinical variables. Our findings highlight that the mapping of atypical inter-hemispheric asymmetry and regional atrophy tap into two complementary aspects of temporal lobe epilepsy-related pathology, with the former revealing primary substrates in ipsilateral limbic circuits and the latter capturing bilateral disease effects. These findings refine ou
- Published
- 2022
5. Bioinspired Nanotechnologies for Skin Regeneration
- Author
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Tavakol, S., primary, Jalili-Firoozinezhad, S., additional, Mashinchian, O., additional, and Mahmoudi, M., additional
- Published
- 2016
- Full Text
- View/download PDF
6. Bone regeneration based on nano-hydroxyapatite and hydroxyapatite/chitosan nanocomposites: an in vitro and in vivo comparative study
- Author
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Tavakol, S., Nikpour, M. R., Amani, A., Soltani, M., Rabiee, S. M., Rezayat, S. M., Chen, P., and Jahanshahi, M.
- Published
- 2013
- Full Text
- View/download PDF
7. Necrotic, apoptotic and autophagic cell fates triggered by nanoparticles
- Author
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Mohammadinejad, R., Moosavi, M.A., Tavakol, S., Vardar, D.Ö., Hosseini, A., Rahmati, M., Klionsky, D.J., and [Belirlenecek]
- Subjects
autophagy ,stress ,cell death ,nanotoxicity ,lysosome ,Apoptosis ,nanoparticles ,necrosis - Abstract
Nanomaterials have gained a rapid increase in use in a variety of applications that pertain to many aspects of human life. The majority of these innovations are centered on medical applications and a range of industrial and environmental uses ranging from electronics to environmental remediation. Despite the advantages of NPs, the knowledge of their toxicological behavior and their interactions with the cellular machinery that determines cell fate is extremely limited. This review is an attempt to summarize and increase our understanding of the mechanistic basis of nanomaterial interactions with the cellular machinery that governs cell fate and activity. We review the mechanisms of NP-induced necrosis, apoptosis and autophagy and potential implications of these pathways in nanomaterial-induced outcomes. Abbreviations: Ag, silver; CdTe, cadmium telluride; CNTs, carbon nanotubes; EC, endothelial cell; GFP, green fluorescent protein; GO, graphene oxide; GSH, glutathione; HUVECs, human umbilical vein endothelial cells; NP, nanoparticle; PEI, polyethylenimine; PVP, polyvinylpyrrolidone; QD, quantum dot; ROS, reactive oxygen species; SiO2, silicon dioxide; SPIONs, superparamagnetic iron oxide nanoparticles; SWCNT, single-walled carbon nanotubes; TiO2, titanium dioxide; USPION, ultra-small super paramagnetic iron oxide; ZnO, zinc oxide. © 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group. National Institutes of Health, NIH; National Institute of General Medical Sciences, NIGMS: GM053396; Honeywell Hometown Solutions, HHS; Kerman University of Medical Sciences, KMU; National Institute for Genetic Engineering and Biotechnology, NIGEB; National Institute for Medical Research Development, NIMAD: 940943 Reza Mohammadinejad is thankful for the financial support of Kerman University of Medical Sciences. Amin Moosavi acknowledges National Institute for Medical Research Development (NIMAD) grant 940943 and financial supports of National Institute of Genetic Engineering and Biotechnology and Iranian National Science Foundation. Daniel J. Klionsky is supported by NIH grant GM053396. This work was supported by the HHS | NIH | National Institute of General Medical Sciences (NIGMS) [GM053396]. 2-s2.0-85057096523 PubMed: 30160607
- Published
- 2019
8. Neuroimaging and connectomics of drug-resistant epilepsy at multiple scales: From focal lesions to macroscale networks
- Author
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Tavakol, S, Royer, J, Lowe, AJ, Bonilha, L, Tracy, JI, Jackson, GD, Duncan, JS, Bernasconi, A, Bernasconi, N, Bernhardt, BC, Tavakol, S, Royer, J, Lowe, AJ, Bonilha, L, Tracy, JI, Jackson, GD, Duncan, JS, Bernasconi, A, Bernasconi, N, and Bernhardt, BC
- Abstract
Epilepsy is among the most common chronic neurologic disorders, with 30%-40% of patients having seizures despite antiepileptic drug treatment. The advent of brain imaging and network analyses has greatly improved the understanding of this condition. In particular, developments in magnetic resonance imaging (MRI) have provided measures for the noninvasive characterization and detection of lesions causing epilepsy. MRI techniques can probe structural and functional connectivity, and network analyses have shaped our understanding of whole-brain anomalies associated with focal epilepsies. This review considers the progress made by neuroimaging and connectomics in the study of drug-resistant epilepsies due to focal substrates, particularly temporal lobe epilepsy related to mesiotemporal sclerosis and extratemporal lobe epilepsies associated with malformations of cortical development. In these disorders, there is evidence of widespread disturbances of structural and functional connectivity that may contribute to the clinical and cognitive prognosis of individual patients. It is hoped that studying the interplay between macroscale network anomalies and lesional profiles will improve our understanding of focal epilepsies and assist treatment choices.
- Published
- 2019
9. Chapter 26 - Bioinspired Nanotechnologies for Skin Regeneration
- Author
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Tavakol, S., Jalili-Firoozinezhad, S., Mashinchian, O., and Mahmoudi, M.
- Published
- 2016
- Full Text
- View/download PDF
10. Bone regeneration based on nano-hydroxyapatite and hydroxyapatite/chitosan nanocomposites: an in vitro and in vivo comparative study
- Author
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Tavakol, S., primary, Nikpour, M. R., additional, Amani, A., additional, Soltani, M., additional, Rabiee, S. M., additional, Rezayat, S. M., additional, Chen, P., additional, and Jahanshahi, M., additional
- Published
- 2012
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- View/download PDF
11. Gastrointestinal Helminths of Magpies (Pica pica), Rooks (Corvus frugilegus) and Carrion Crows (Corvus corone) in Mazandaran Province, North of Iran.
- Author
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Halajian, A., Eslami, A., Mobedi, I., Amin, O., Mariaux, J., Mansoori, J., and Tavakol, S.
- Subjects
HELMINTHS ,MAGPIES ,BLACK-billed magpie ,CORVUS frugilegus ,CARRION crow - Abstract
Background: Corvidae is a cosmopolitan family of oscine birds including crows, rooks, magpies, jays, chough, and ravens. These birds are migratory species, especially in the shortage of foods, so they can act like vectors for a wide range of microorganisms. They live generally in temperate climates and in a very close contact with human residential areas as well as poultry farms. There is no available information in the literature concerning the parasitic infections of these three species of corvidae in Mazandaran Province, northern Iran, so this study was conducted to clarify this. Methods: As there are three species of corvid birds in Mazandaran Province, 106 birds including 79 magpies, 11 rooks, and 16 carrion crows were examined between winter 2007 and spring 2008 at post mortem for gastrointestinal helminths. The helminths were drawn and identified morphologically in the Laboratory of Parasitology, Islamic Azad University, Science and Research Branch, Tehran and also partly in the School of Public Health, Tehran University of Medical Sciences, based on the reference books and identification keys like Soulsby, Khalil et al. and Anderson et al. Results: Four species of nematodes, 2 species of cestodes, 1 species of trematodes and 1 species of acanthocephalans were identified in these three corvid species. Conclusion: Five species of the helminths are identified for the first time in Iran, and the acanthocephalan species is new host record for rooks. It is clear that these corvid birds have diverse range of helminths and can act as carriers for infecting the domestic fowls. [ABSTRACT FROM AUTHOR]
- Published
- 2011
12. Developing a screening inventory reading test (IRT) for the Isfahanian students of the first to fifth grade.
- Author
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Shafiei B, Tavakol S, Alinia L, Maracy MR, Sedaghati L, and Foroughi R
- Published
- 2009
13. The relationship between family-to-work conflict of employee and co-workers' turnover intention
- Author
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Tavakol Sharafi and Zohreh dehdashti shahrokh
- Subjects
Work–family conflict ,Employee engagement ,Turnover intention ,Business records management ,HF5735-5746 - Abstract
Previous studies have convincingly shown that employees' family lives can affect their work outcomes. We investigate whether family-to-work conflict (FWC) experienced by the employee also affects the turnover intention of a co-worker. We predict that the employee's FWC has an effect on the co-worker's turnover intention through the crossover of positive and negative work attitudes. Using a sample of 154 co-worker dyads, we found that the employee FWC was positively related to co-worker turnover intention through the crossover of (reduced) work engagement. Results show that family matters at work, affecting employee. In addition, employee's job engagement was positively related to his (her) co-worker job engagement and it was negatively related co-worker turnover intention and employee's FWC was not positively related to co-worker turnover intention trough the crossover of (reduced) feelings of engagement.
- Published
- 2012
14. The relationship between dimensions of intellectual capital and knowledge creation: Case Study of the headquarters of national gas corporation of Iran
- Author
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Mehdi Sharafi, Yousof Mohammadi moghadam, and Tavakol Sharafi
- Subjects
Intellectual capital ,Structural capital ,Relational capital ,Human capital ,Knowledge creation ,Business records management ,HF5735-5746 - Abstract
Intellectual capital is the main property of any organization in knowledge-based economics. Knowledge is the fundamental principle of intellectual capital. Hence, it is the core of organizational capabilities. The aim of this study is to survey the relationship between dimensions of intellectual capital and knowledge creation in the headquarters of National Gas Corporation of Iran in the year 2010. The research method is descriptive – survey and follows practical objective. The research population consists of the formal staffs of the Corporation (managers, senior staff and other staff). We selected 261 people from the population randomly. We also used a reliable and valid questionnaire to gather data. We also used informative factor analysis to examine goodness of the model and we used SEM by Lisrel to confirm or reject the hypothesis in this study. The results show that all dimensions of intellectual capital have a significant impact on dimensions of knowledge creation, except for the effects of structural capital on knowledge combination as well as relational capital on knowledge internalization.
- Published
- 2012
15. Application of electrospun gelatin nanofibers in tissue engineering
- Author
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Naghibzadeh, M., Firoozi, S., Nodoushan, F. S., Adabi, M., Khoradmehr, A., Fesahat, F., Esnaashari, S. S., Khosravani, M., Tavakol, S., Pazoki-Toroudi, H., Adel, M., and Masoumeh Zahmatkeshan
16. Gastrointestinal helminths of magpies (pica pica), rooks (corvus frugilegus) and carrion crows (corvus corone) in mazandaran province, North of Iran
- Author
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Ali Halajian, Eslami A, Mobedi I, Amin O, Mariaux J, Mansoori J, and Tavakol S
- Subjects
Magpie ,Crow ,Helminths ,lcsh:RC109-216 ,Original Article ,Rook ,Iran ,lcsh:Infectious and parasitic diseases - Abstract
Background: Corvidae is a cosmopolitan family of oscine birds including crows, rooks, magpies, jays, chough, and ravens. These birds are migratory species, especially in the shortage of foods, so they can act like vectors for a wide range of microorganisms. They live generally in temperate climates and in a very close contact with human residential areas as well as poultry farms. There is no available information in the literature concerning the parasitic infections of these three species of corvidae in Mazandaran Province, northern Iran, so this study was conducted to clarify this. Methods: As there are three species of corvid birds in Mazandaran Province, 106 birds including 79 magpies, 11 rooks, and 16 carrion crows were examined between winter 2007 and spring 2008 at post mortem for gastrointestinal helminths. The helminths were drawn and identified morphologically in the Laboratory of Parasitology, Islamic Azad University, Science and Research Branch, Tehran and also partly in the School of Public Health, Tehran University of Medical Sciences, based on the reference books and identification keys like Soulsby, Khalil et al. and Anderson et al. Results: Four species of nematodes, 2 species of cestodes, 1 species of trematodes and 1 species of acanthocephalans were identified in these three corvid species. Conclusion: Five species of the helminths are identified for the first time in Iran, and the acanthocephalan species is new host record for rooks. It is clear that these corvid birds have diverse range of helminths and can act as carriers for infecting the domestic fowls.
17. Healing potential of fibroblast cells cultured on a PLA/CS nanofibrous scaffold in skin regeneration in Wistar rat
- Author
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Hoveizi, E., Tayebeh Mohammadi, Ebrahimi-Barough, S., and Tavakol, S.
18. Gold nanoparticles for biomedical imaging and their biological response
- Author
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Omid Mashinchian, Alkilany, A. M., Hajipour, M. J., and Tavakol, S.
19. Psychometric properties and confirmatory factor analysis of the Jefferson Scale of Physician Empathy
- Author
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Tavakol Sina, Dennick Reg, and Tavakol Mohsen
- Subjects
Empathy ,JSPE ,confirmatory factor analysis ,structure validation ,Special aspects of education ,LC8-6691 ,Medicine - Abstract
Abstract Background Empathy towards patients is considered to be associated with improved health outcomes. Many scales have been developed to measure empathy in health care professionals and students. The Jefferson Scale of Physician Empathy (JSPE) has been widely used. This study was designed to examine the psychometric properties and the theoretical structure of the JSPE. Methods A total of 853 medical students responded to the JSPE questionnaire. A hypothetical model was evaluated by structural equation modelling to determine the adequacy of goodness-of-fit to sample data. Results The model showed excellent goodness-of-fit. Further analysis showed that the hypothesised three-factor model of the JSPE structure fits well across the gender differences of medical students. Conclusions The results supported scale multi-dimensionality. The 20 item JSPE provides a valid and reliable scale to measure empathy among not only undergraduate and graduate medical education programmes, but also practising doctors. The limitations of the study are discussed and some recommendations are made for future practice.
- Published
- 2011
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- View/download PDF
20. A descriptive study of medical educators' views of problem-based learning
- Author
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Dennick Reg, Tavakol Mohsen, and Tavakol Sina
- Subjects
Special aspects of education ,LC8-6691 ,Medicine - Abstract
Abstract Background There is a growing amount of literature on the benefits and drawbacks of Problem-Based Learning (PBL) compared to conventional curricula. However, it seems that PBL research studies do not provide information rigorously and formally that can contribute to making evidence-based medical education decisions. The authors performed an investigation aimed at medical education scholars around the question, "What are the views of medical educators concerning the PBL approach?" Methods After framing the question, the method of data collection relied on asking medical educators to report their views on PBL. Two methods were used for collecting data: the questionnaire survey and an online discussion forum. Results The descriptive analysis of the study showed that many participants value the PBL approach in the practice and training of doctors. However, some participants hold contrasting views upon the importance of the PBL approach in basic medical education. For example, more than a third of participants (38.5%) had a neutral stance on PBL as a student-oriented educational approach. The same proportion of participants also had a neutral view of the efficiency of traditional learning compared to a PBL tutorial. The open-ended question explored the importance of faculty development in PBL. A few participants had negative perceptions of the epistemological assumptions of PBL. Two themes emerged from the analysis of the forum repliers: the importance of the faculty role and self-managed education. Conclusion Whilst many participants valued the importance of the PBL approach in the practice and training of doctors and agreed with most of the conventional descriptions of PBL, some participants held contrasting views on the importance of the PBL approach in undergraduate medical education. However there was a strong view concerning the importance of facilitator training. More research is needed to understand the process of PBL better.
- Published
- 2009
- Full Text
- View/download PDF
21. Differential reorganization of episodic and semantic memory systems in epilepsy-related mesiotemporal pathology.
- Author
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Cabalo DG, DeKraker J, Royer J, Xie K, Tavakol S, Rodríguez-Cruces R, Bernasconi A, Bernasconi N, Weil A, Pana R, Frauscher B, Caciagli L, Jefferies E, Smallwood J, and Bernhardt BC
- Subjects
- Humans, Male, Female, Adult, Middle Aged, Temporal Lobe physiopathology, Temporal Lobe pathology, Temporal Lobe diagnostic imaging, Young Adult, Neocortex physiopathology, Neocortex diagnostic imaging, Neocortex pathology, Connectome methods, Memory Disorders etiology, Memory Disorders physiopathology, Memory Disorders pathology, Nerve Net diagnostic imaging, Nerve Net physiopathology, Nerve Net pathology, Epilepsy, Temporal Lobe physiopathology, Epilepsy, Temporal Lobe pathology, Epilepsy, Temporal Lobe diagnostic imaging, Memory, Episodic, Magnetic Resonance Imaging, Hippocampus pathology, Hippocampus diagnostic imaging, Hippocampus physiopathology, Semantics
- Abstract
Declarative memory encompasses episodic and semantic divisions. Episodic memory captures singular events with specific spatiotemporal relationships, whereas semantic memory houses context-independent knowledge. Behavioural and functional neuroimaging studies have revealed common and distinct neural substrates of both memory systems, implicating mesiotemporal lobe (MTL) regions such as the hippocampus and distributed neocortices. Here, we explored declarative memory system reorganization in patients with unilateral temporal lobe epilepsy (TLE) as a human disease model to test the impact of variable degrees of MTL pathology on memory function. Our cohort included 31 patients with TLE and 60 age- and sex-matched healthy controls, and all participants underwent episodic and semantic retrieval tasks during a multimodal MRI session. The functional MRI tasks were closely matched in terms of stimuli and trial design. Capitalizing on non-linear connectome gradient-mapping techniques, we derived task-based functional topographies during episodic and semantic memory states, in both the MTL and neocortical networks. Comparing neocortical and hippocampal functional gradients between TLE patients and healthy controls, we observed a marked topographic reorganization of both neocortical and MTL systems during episodic memory states. Neocortical alterations were characterized by reduced functional differentiation in TLE across lateral temporal and midline parietal cortices in both hemispheres. In the MTL, in contrast, patients presented with a more marked functional differentiation of posterior and anterior hippocampal segments ipsilateral to the seizure focus and pathological core, indicating perturbed intrahippocampal connectivity. Semantic memory reorganization was also found in bilateral lateral temporal and ipsilateral angular regions, whereas hippocampal functional topographies were unaffected. Furthermore, leveraging MRI proxies of MTL pathology, we observed alterations in hippocampal microstructure and morphology that were associated with TLE-related functional reorganization during episodic memory. Moreover, correlation analysis and statistical mediation models revealed that these functional alterations contributed to behavioural deficits in episodic memory, but again not in semantic memory in patients. Altogether, our findings suggest that semantic processes rely on distributed neocortical networks, whereas episodic processes are supported by a network involving both the hippocampus and the neocortex. Alterations of such networks can provide a compact signature of state-dependent reorganization in conditions associated with MTL damage, such as TLE., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Guarantors of Brain.)
- Published
- 2024
- Full Text
- View/download PDF
22. Unraveling Dysregulated Cell Signaling Pathways, Genetic and Epigenetic Mysteries of Parkinson's Disease.
- Author
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Hamidpour SK, Amiri M, Ketabforoush AHME, Saeedi S, Angaji A, and Tavakol S
- Subjects
- Humans, Animals, Parkinson Disease genetics, Parkinson Disease metabolism, Epigenesis, Genetic, Signal Transduction genetics
- Abstract
Parkinson's disease (PD) is a prevalent and burdensome neurodegenerative disorder that has been extensively researched to understand its complex etiology, diagnosis, and treatment. The interplay between genetic and environmental factors in PD makes its pathophysiology difficult to comprehend, emphasizing the need for further investigation into genetic and epigenetic markers involved in the disease. Early diagnosis is crucial for optimal management of the disease, and the development of novel diagnostic biomarkers is ongoing. Although many efforts have been made in the field of recognition and interpretation of the mechanisms involved in the pathophysiology of the disease, the current knowledge about PD is just the tip of the iceberg. By scrutinizing genetic and epigenetic patterns underlying PD, new avenues can be opened for dissecting the pathology of the disorder, leading to more precise and efficient diagnostic and therapeutic approaches. This review emphasizes the importance of studying dysregulated cell signaling pathways and molecular processes associated with genes and epigenetic alterations in understanding PD, paving the way for the development of novel therapeutic strategies to combat this devastating disease., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
- Published
- 2024
- Full Text
- View/download PDF
23. Unveiling the Therapeutic Potential of Small Molecule of SVAK-12: A Comprehensive In Silico, In Vitro, and In Vivo Studies on its Neuroprotective Effects and Molecular Interactions in Parkinson's Disease.
- Author
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Kokabi S, Amiri M, Alahdad N, Yazdanpanah MA, Shahbazi A, Barati M, Simorgh S, Azedi F, Angaji SA, and Tavakol S
- Abstract
Introduction: Parkinson's disease (PD) is a neurodegenerative disorder associated with a progressive loss of dopaminergic cells and as of now, there is no established definitive treatment available for this condition., Method: In this study, the focus was on investigating the impact of SVAK-12, a small molecule that can cross the blood-brain barrier and remain stable without structural changes. The effect of SVAK-12 was investigated in vitro on neurotoxicity, in vivo model of Parkinson's Diseases and in silico., Result: Through in vitro and in vivo experiments, as well as molecular docking simulations, it was found that SVAK-12 (375 ng.ml) led to increased cell viability, reduced cellular damage, and decreased production of NO and ROS. Additionally, it boosted levels of important neurotrophic factors like BDNF (130.49%) and GDNF (116.38%), potentially aiding in alleviating motor disability and depression. The study also highlighted SVAK-12's potential as a therapeutic candidate for neurological disorders due to its ability to increase tyrosine hydroxylase expression and dopamine levels (4.84 times). While it did not significantly improve motor symptoms in vivo, it did enhance motor asymmetry in the forelimbs and gene expression related to brain regions. Besides, it induced significant BMP-2 gene expression in substantial nigra regions without significant changes in GDNF and Nurr1 gene expression in the striatum expression. The docking of SVAK-12, Levodopa, Amantadine, Biperiden, Selegiline, and Rasagiline to the binding site of GFRα1, sortilin, and TrkB showed that SVAK-12 had greater MolDock score than Selegiline and Amantadine for GFRα1 and greater than amantadine for Sortilin and TrKB., Conclusion: Overall, the study suggests that SVAK-12's neuro-biocompatibility, ability to reduce free radicals, and enhanced neurotrophic factors make it a promising candidate as a neuroprotective drug., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
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- 2024
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24. Brain Networks for Cortical Atrophy and Responsive Neurostimulation in Temporal Lobe Epilepsy.
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Larivière S, Schaper FLWVJ, Royer J, Rodríguez-Cruces R, Xie K, DeKraker J, Ngo A, Sahlas E, Chen J, Tavakol S, Drew W, Morton-Dutton M, Warren AEL, Baratono SR, Rolston JD, Weng Y, Bernasconi A, Bernasconi N, Concha L, Zhang Z, Frauscher B, Bernhardt BC, and Fox MD
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Importance: Drug-resistant temporal lobe epilepsy (TLE) has been associated with hippocampal pathology. Most surgical treatment strategies, including resection and responsive neurostimulation (RNS), focus on this disease epicenter; however, imaging alterations distant from the hippocampus, as well as emerging data from responsive neurostimulation trials, suggest conceptualizing TLE as a network disorder., Objective: To assess whether brain networks connected to areas of atrophy in the hippocampus align with the topography of distant neuroimaging alterations and RNS response., Design, Setting, and Participants: This retrospective case-control study was conducted between July 2009 and June 2022. Data collection for this multicenter, population-based study took place across 4 tertiary referral centers in Montréal, Canada; Querétaro, México; Nanjing, China; and Salt Lake City, Utah. Eligible patients were diagnosed with TLE according to International League Against Epilepsy criteria and received either neuroimaging or neuroimaging and RNS to the hippocampus. Patients with encephalitis, traumatic brain injury, or bilateral TLE were excluded., Main Outcomes and Measures: Spatial alignment between brain network topographies., Results: Of the 110 eligible patients, 94 individuals diagnosed with TLE were analyzed (51 [54%] female; mean [SD] age, 31.3 [10.9] years). Hippocampal thickness maps in TLE were compared to 120 healthy control individuals (66 [55%] female; mean [SD] age, 29.8 [9.5] years), and areas of atrophy were identified. Using an atlas of normative connectivity (n = 1000), 2 brain networks were identified that were functionally connected to areas of hippocampal atrophy. The first network was defined by positive correlations to temporolimbic, medial prefrontal, and parietal regions, whereas the second network by negative correlations to frontoparietal regions. White matter changes colocalized to the positive network (t93 = -3.82; P = 2.44 × 10-4). In contrast, cortical atrophy localized to the negative network (t93 = 3.54; P = 6.29 × 10-3). In an additional 38 patients (20 [53%] female; mean [SD] age, 35.8 [11.3] years) treated with RNS, connectivity between the stimulation site and atrophied regions within the negative network was associated with seizure reduction (t212 = -2.74; P = .007)., Conclusions and Relevance: The findings in this study indicate that distributed pathology in TLE may occur in brain networks connected to the hippocampal epicenter. Connectivity to these same networks was associated with improvement following RNS. A network approach to TLE may reveal therapeutic targets outside the traditional target in the hippocampus.
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- 2024
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25. Contemporary Prognostic Signatures and Refined Risk Stratification of Gliomas: An Analysis of 4,400 Tumors.
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Ghosh HS, Patel RV, Woodward E, Greenwald NF, Bhave VM, Maury EA, Cello G, Hoffman SE, Li Y, Gupta H, Youssef G, Spurr LF, Vogelzang J, Touat M, Dubois F, Cherniack AD, Guo X, Tavakol S, Cioffi G, Lindeman NI, Ligon AH, Chiocca EA, Reardon DA, Wen PY, Meredith D, Santagata S, Barnholtz-Sloan JS, Ligon KL, Beroukhim R, and Bi WL
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Background: With the significant shift in the classification, risk stratification, and standards of care for gliomas, we sought to understand how the overall survival of patients with these tumors is impacted by molecular features, clinical metrics, and treatment received., Methods: We assembled a cohort of patients with a histopathologically diagnosed glioma from The Cancer Genome Atlas, Project Genomics Evidence Neoplasia Information Exchange, and Dana-Farber Cancer Institute/Brigham and Women's Hospital. This incorporated retrospective clinical, histological, and molecular data alongside prospective assessment of patient survival., Results: 4,400 gliomas were identified: 2,195 glioblastoma, 1,198 IDH1/2-mutant astrocytoma, 531 oligodendroglioma, 271 other IDH1/2-wildtype glioma, and 205 pediatric-type glioma. Molecular classification updated 27.2% of gliomas from their original histopathologic diagnosis. Examining the distribution of molecular alterations across glioma subtypes revealed mutually exclusive alterations within tumorigenic pathways. Non-TCGA patients had significantly improved overall survival compared to TCGA patients, with 26.7%, 55.6%, and 127.8% longer survival for glioblastoma, IDH1/2-mutant astrocytoma, and oligodendroglioma respectively (all p<0.01). Several prognostic features were characterized, including NF1 alteration and 21q loss in glioblastoma, and EGFR amplification and 22q loss in IDH1/2-mutant astrocytoma. Leveraging the size of this cohort, nomograms were generated to assess the probability of overall survival based on patient age, the molecular features of a tumor, and the treatment received., Conclusions: By applying modern molecular criteria, we characterize the genomic diversity across glioma subtypes, identify clinically applicable prognostic features, and provide a contemporary update on patient survival to serve as a reference for ongoing investigations., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Neuro-Oncology.)
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- 2024
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26. Associations of Cerebral Blood Flow Patterns With Gray and White Matter Structure in Patients With Temporal Lobe Epilepsy.
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Ngo A, Royer J, Rodriguez-Cruces R, Xie K, DeKraker J, Auer H, Tavakol S, Lam J, Schrader DV, Dudley RWR, Bernasconi A, Bernasconi N, Frauscher B, Lariviere S, and Bernhardt BC
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- Humans, Female, Male, Adult, Magnetic Resonance Imaging, Middle Aged, Diffusion Magnetic Resonance Imaging, Supervised Machine Learning, Young Adult, Drug Resistant Epilepsy physiopathology, Drug Resistant Epilepsy diagnostic imaging, Drug Resistant Epilepsy pathology, Epilepsy, Temporal Lobe physiopathology, Epilepsy, Temporal Lobe diagnostic imaging, White Matter diagnostic imaging, White Matter pathology, White Matter blood supply, Cerebrovascular Circulation physiology, Gray Matter diagnostic imaging, Gray Matter blood supply, Gray Matter pathology, Gray Matter physiopathology
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Background and Objectives: Neuroimaging studies in patients with temporal lobe epilepsy (TLE) show widespread brain network alterations beyond the mesiotemporal lobe. Despite the critical role of the cerebrovascular system in maintaining whole-brain structure and function, changes in cerebral blood flow (CBF) remain incompletely understood in the disease. Here, we studied whole-brain perfusion and vascular network alterations in TLE and assessed its associations with gray and white matter compromises and various clinical variables., Methods: We included individuals with and without pharmaco-resistant TLE who underwent multimodal 3T MRI, including arterial spin labelling, structural, and diffusion-weighted imaging. Using surface-based MRI mapping, we generated individualized cortico-subcortical profiles of perfusion, morphology, and microstructure. Linear models compared regional CBF in patients with controls and related alterations to morphological and microstructural metrics. We further probed interregional vascular networks in TLE, using graph theoretical CBF covariance analysis. The effects of disease duration were explored to better understand the progressive changes in perfusion. We assessed the utility of perfusion in separating patients with TLE from controls using supervised machine learning., Results: Compared with control participants (n = 38; mean ± SD age 34.8 ± 9.3 years; 20 females), patients with TLE (n = 24; mean ± SD age 35.8 ± 10.6 years; 12 females) showed widespread CBF reductions predominantly in fronto-temporal regions (Cohen d -0.69, 95% CI -1.21 to -0.16), consistent in a subgroup of patients who remained seizure-free after surgical resection of the seizure focus. Parallel structural profiling and network-based models showed that cerebral hypoperfusion may be partially constrained by gray and white matter changes (8.11% reduction in Cohen d ) and topologically segregated from whole-brain perfusion networks (area under the curve -0.17, p < 0.05). Negative effects of progressive disease duration further targeted regional CBF profiles in patients ( r = -0.54, 95% CI -0.77 to -0.16). Perfusion-derived classifiers discriminated patients from controls with high accuracy (71% [70%-82%]). Findings were robust when controlling for several methodological confounds., Discussion: Our multimodal findings provide insights into vascular contributions to TLE pathophysiology affecting and extending beyond mesiotemporal structures and highlight their clinical potential in epilepsy diagnosis. As our work was cross-sectional and based on a single site, it motivates future longitudinal studies to confirm progressive effects, ideally in a multicentric setting.
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- 2024
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27. Correction: Firoozi et al. A Cell-Free SDKP-Conjugated Self-Assembling Peptide Hydrogel Sufficient for Improvement of Myocardial Infarction. Biomolecules 2020, 10 , 205.
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Firoozi S, Pahlavan S, Ghanian MH, Rabbani S, Tavakol S, Barekat M, Yakhkeshi S, Mahmoudi E, Soleymani M, and Baharvand H
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The authors wish to make the following corrections to this paper [...].
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- 2024
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28. Differential relational memory impairment in temporal lobe epilepsy.
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Tavakol S, Kebets V, Royer J, Li Q, Auer H, DeKraker J, Jefferies E, Bernasconi N, Bernasconi A, Helmstaedter C, Arafat T, Armony J, Nathan Spreng R, Caciagli L, Frauscher B, Smallwood J, and Bernhardt B
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- Humans, Male, Female, Adult, Middle Aged, Neuropsychological Tests, Hippocampus pathology, Young Adult, Spatial Memory physiology, Semantics, Epilepsy, Temporal Lobe psychology, Epilepsy, Temporal Lobe complications, Memory Disorders etiology, Memory, Episodic
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Objective: Temporal lobe epilepsy (TLE) is typically associated with pathology of the hippocampus, a key structure involved in relational memory, including episodic, semantic, and spatial memory processes. While it is widely accepted that TLE-associated hippocampal alterations underlie memory deficits, it remains unclear whether impairments relate to a specific cognitive domain or multiple ones., Methods: We administered a recently validated task paradigm to evaluate episodic, semantic, and spatial memory in 24 pharmacoresistant TLE patients and 50 age- and sex-matched healthy controls. We carried out two-way analyses of variance to identify memory deficits in individuals with TLE relative to controls across different relational memory domains, and used partial least squares correlation to identify factors contributing to variations in relational memory performance across both cohorts., Results: Compared to controls, TLE patients showed marked impairments in episodic and spatial memory, with mixed findings in semantic memory. Even when additionally controlling for age, sex, and overall cognitive function, between-group differences persisted along episodic and spatial domains. Moreover, age, diagnostic group, and hippocampal volume were all associated with relational memory behavioral phenotypes., Significance: Our behavioral findings show graded deficits across relational memory domains in people with TLE, which provides further insights into the complex pattern of cognitive impairment in the condition., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)
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- 2024
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29. Atypical connectome topography and signal flow in temporal lobe epilepsy.
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Xie K, Royer J, Larivière S, Rodriguez-Cruces R, Frässle S, Cabalo DG, Ngo A, DeKraker J, Auer H, Tavakol S, Weng Y, Abdallah C, Arafat T, Horwood L, Frauscher B, Caciagli L, Bernasconi A, Bernasconi N, Zhang Z, Concha L, and Bernhardt BC
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- Humans, Female, Male, Adult, Middle Aged, Magnetic Resonance Imaging, Young Adult, Brain diagnostic imaging, Brain physiopathology, Brain pathology, Cohort Studies, Nerve Net diagnostic imaging, Nerve Net physiopathology, Nerve Net pathology, Epilepsy, Temporal Lobe physiopathology, Epilepsy, Temporal Lobe diagnostic imaging, Epilepsy, Temporal Lobe pathology, Connectome
- Abstract
Temporal lobe epilepsy (TLE) is the most common pharmaco-resistant epilepsy in adults. While primarily associated with mesiotemporal pathology, recent evidence suggests that brain alterations in TLE extend beyond the paralimbic epicenter and impact macroscale function and cognitive functions, particularly memory. Using connectome-wide manifold learning and generative models of effective connectivity, we examined functional topography and directional signal flow patterns between large-scale neural circuits in TLE at rest. Studying a multisite cohort of 95 patients with TLE and 95 healthy controls, we observed atypical functional topographies in the former group, characterized by reduced differentiation between sensory and transmodal association cortices, with most marked effects in bilateral temporo-limbic and ventromedial prefrontal cortices. These findings were consistent across all study sites, present in left and right lateralized patients, and validated in a subgroup of patients with histopathological validation of mesiotemporal sclerosis and post-surgical seizure freedom. Moreover, they were replicated in an independent cohort of 30 TLE patients and 40 healthy controls. Further analyses demonstrated that reduced differentiation related to decreased functional signal flow into and out of temporolimbic cortical systems and other brain networks. Parallel analyses of structural and diffusion-weighted MRI data revealed that topographic alterations were independent of TLE-related cortical thinning but partially mediated by white matter microstructural changes that radiated away from paralimbic circuits. Finally, we found a strong association between the degree of functional alterations and behavioral markers of memory dysfunction. Our work illustrates the complex landscape of macroscale functional imbalances in TLE, which can serve as intermediate markers bridging microstructural changes and cognitive impairment., Competing Interests: Declaration of Competing Interest The authors report no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
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- 2024
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30. The impact of social determinants of health on early outcomes after adult Chiari surgery.
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Tavakol S, Zieles K, Peters M, Omini M, Chen S, and Jea A
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- Humans, Treatment Outcome, Retrospective Studies, Social Determinants of Health, Decompression, Surgical, Arnold-Chiari Malformation surgery
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We sought to identify social determinants of health (SDoH) for adult patients undergoing Chiari decompression surgery and to analyze their association with postoperative outcomes, including length of stay (LOS), return to the system within 30 days, and the Chicago Chiari Outcomes Score (CCOS). This is a retrospective study of adult patients who underwent Chiari decompression surgery between June 2021 and January 2023. Data was gathered through electronic medical record review and telephone surveys. Descriptive statistics were used to evaluate demographics of all patients meeting inclusion criteria. Fisher's exact tests and logistic regression were used for data analysis. A total of 37 patients underwent Chiari decompression (23 CCOS/SDoH survey respondents): 48% bony decompression only, 30% bony decompression plus intradural exploration, and 22% occipitocervical fusion. Seven patients (30%) had a LOS > 2 days, 1 patient (4%) required inpatient rehabilitation postoperatively, 4 patients (17%) returned to the system within 30 days, 10 patients (43%) had an extremely favorable CCOS (15-16), and 11 patients (48%) reported interaction with a Chiari support group. Mean follow-up was 9.5 months. Patients with occipitocervical fusion were more likely to have a LOS > 2 days (p = 0.03), patients who exercised ≥ 3 days per week were more likely to have a favorable CCOS (p = 0.04), and patients who participated in a Chiari support group were less likely to have a favorable CCOS (p = 0.03). Chiari decompression plus occipitocervical fusion may be associated with increased LOS. While more frequent exercise may be associated with better post-surgical outcomes, participation in a Chiari support group may be correlated with worse outcomes., (© 2023. The Author(s), under exclusive licence to American Aging Association.)
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- 2024
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31. The human brain connectome weighted by the myelin content and total intra-axonal cross-sectional area of white matter tracts.
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Nelson MC, Royer J, Lu WD, Leppert IR, Campbell JSW, Schiavi S, Jin H, Tavakol S, Vos de Wael R, Rodriguez-Cruces R, Pike GB, Bernhardt BC, Daducci A, Misic B, and Tardif CL
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A central goal in neuroscience is the development of a comprehensive mapping between structural and functional brain features, which facilitates mechanistic interpretation of brain function. However, the interpretability of structure-function brain models remains limited by a lack of biological detail. Here, we characterize human structural brain networks weighted by multiple white matter microstructural features including total intra-axonal cross-sectional area and myelin content. We report edge-weight-dependent spatial distributions, variance, small-worldness, rich club, hubs, as well as relationships with function, edge length, and myelin. Contrasting networks weighted by the total intra-axonal cross-sectional area and myelin content of white matter tracts, we find opposite relationships with functional connectivity, an edge-length-independent inverse relationship with each other, and the lack of a canonical rich club in myelin-weighted networks. When controlling for edge length, networks weighted by either fractional anisotropy, radial diffusivity, or neurite density show no relationship with whole-brain functional connectivity. We conclude that the co-utilization of structural networks weighted by total intra-axonal cross-sectional area and myelin content could improve our understanding of the mechanisms mediating the structure-function brain relationship., Competing Interests: Competing Interests: The authors have declared that no competing interests exist., (© 2023 Massachusetts Institute of Technology.)
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- 2023
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32. Cortical microstructural gradients capture memory network reorganization in temporal lobe epilepsy.
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Royer J, Larivière S, Rodriguez-Cruces R, Cabalo DG, Tavakol S, Auer H, Ngo A, Park BY, Paquola C, Smallwood J, Jefferies E, Caciagli L, Bernasconi A, Bernasconi N, Frauscher B, and Bernhardt BC
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- Humans, Quality of Life, Brain pathology, Magnetic Resonance Imaging, Brain Mapping, Epilepsy, Temporal Lobe pathology
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Temporal lobe epilepsy (TLE), one of the most common pharmaco-resistant epilepsies, is associated with pathology of paralimbic brain regions, particularly in the mesiotemporal lobe. Cognitive dysfunction in TLE is frequent, and particularly affects episodic memory. Crucially, these difficulties challenge the quality of life of patients, sometimes more than seizures, underscoring the need to assess neural processes of cognitive dysfunction in TLE to improve patient management. Our work harnessed a novel conceptual and analytical approach to assess spatial gradients of microstructural differentiation between cortical areas based on high-resolution MRI analysis. Gradients track region-to-region variations in intracortical lamination and myeloarchitecture, serving as a system-level measure of structural and functional reorganization. Comparing cortex-wide microstructural gradients between 21 patients and 35 healthy controls, we observed a reorganization of this gradient in TLE driven by reduced microstructural differentiation between paralimbic cortices and the remaining cortex with marked abnormalities in ipsilateral temporopolar and dorsolateral prefrontal regions. Findings were replicated in an independent cohort. Using an independent post-mortem dataset, we observed that in vivo findings reflected topographical variations in cortical cytoarchitecture. We indeed found that macroscale changes in microstructural differentiation in TLE reflected increased similarity of paralimbic and primary sensory/motor regions. Disease-related transcriptomics could furthermore show specificity of our findings to TLE over other common epilepsy syndromes. Finally, microstructural dedifferentiation was associated with cognitive network reorganization seen during an episodic memory functional MRI paradigm and correlated with interindividual differences in task accuracy. Collectively, our findings showing a pattern of reduced microarchitectural differentiation between paralimbic regions and the remaining cortex provide a structurally-grounded explanation for large-scale functional network reorganization and cognitive dysfunction characteristic of TLE., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Guarantors of Brain.)
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- 2023
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33. Cancer cells same as zombies reprogram normal cells via the secreted microenvironment.
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Rabiee S, Hoveizi E, Barati M, Salehzadeh A, Joghataei MT, and Tavakol S
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- Humans, Culture Media, Conditioned pharmacology, Culture Media, Conditioned metabolism, Fibroblasts metabolism, DNA metabolism, Tumor Microenvironment, Cell Line, Tumor, Signal Transduction, Neoplasms pathology
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The cancer microenvironment plays a crucial role in promoting metastasis and malignancy even in normal cells. In the present study, the effect of acidic and conditioned media of cancer cells (MDA-MB-231), separately and in combination, was studied for the first time on the cell death mechanisms and DNA methylation of normal fibroblasts (NIH/3T3). Cell survival of conditioned media was rescued by the addition of acidic media to conditioned media, as shown by the results. Cell metabolic activity is deviated in a direction other than the Krebs cycle by acidic media The mitochondrial metabolic activity of all groups was enhanced over time, except for acidic media. Unlike the highest amount of ROS in conditioned media, its level decreased to the level of acidic media in the combination group. Furthermore, cells were deviated towards autophagy, rather than apoptosis, by the addition of acidic media to the conditioned media, unlike the conditioned media. Global DNA methylation analysis revealed significantly higher DNA hypomethylation in acidic media than in normal and combination media. Not only were cells treated with conditioned media rescued by acidic media, but also DNA hypomethylation and apoptosis in the combination group were decreased through epigenetic modifications. The acidic and conditioned media produced by cancer cells can remotely activate malignant signaling pathways, much like zombies, which can cause metabolic and epigenetic changes in normal cells., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Rabiee et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2023
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34. Atypical connectome topography and signal flow in temporal lobe epilepsy.
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Xie K, Royer J, Larivière S, Rodriguez-Cruces R, Frässle S, Cabalo DG, Ngo A, DeKraker J, Auer H, Tavakol S, Weng Y, Abdallah C, Horwood L, Frauscher B, Caciagli L, Bernasconi A, Bernasconi N, Zhang Z, Concha L, and Bernhardt BC
- Abstract
Temporal lobe epilepsy (TLE) is one of the most common pharmaco-resistant epilepsies in adults. While hippocampal pathology is the hallmark of this condition, emerging evidence indicates that brain alterations extend beyond the mesiotemporal epicenter and affect macroscale brain function and cognition. We studied macroscale functional reorganization in TLE, explored structural substrates, and examined cognitive associations. We investigated a multisite cohort of 95 patients with pharmaco-resistant TLE and 95 healthy controls using state-of-the-art multimodal 3T magnetic resonance imaging (MRI). We quantified macroscale functional topographic organization using connectome dimensionality reduction techniques and estimated directional functional flow using generative models of effective connectivity. We observed atypical functional topographies in patients with TLE relative to controls, manifesting as reduced functional differentiation between sensory/motor networks and transmodal systems such as the default mode network, with peak alterations in bilateral temporal and ventromedial prefrontal cortices. TLE-related topographic changes were consistent in all three included sites and reflected reductions in hierarchical flow patterns between cortical systems. Integration of parallel multimodal MRI data indicated that these findings were independent of TLE-related cortical grey matter atrophy, but mediated by microstructural alterations in the superficial white matter immediately beneath the cortex. The magnitude of functional perturbations was robustly associated with behavioral markers of memory function. Overall, this work provides converging evidence for macroscale functional imbalances, contributing microstructural alterations, and their associations with cognitive dysfunction in TLE.
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- 2023
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35. Atypical intrinsic neural timescales in temporal lobe epilepsy.
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Xie K, Royer J, Lariviere S, Rodriguez-Cruces R, de Wael RV, Park BY, Auer H, Tavakol S, DeKraker J, Abdallah C, Caciagli L, Bassett DS, Bernasconi A, Bernasconi N, Frauscher B, Concha L, and Bernhardt BC
- Subjects
- Adult, Humans, Magnetic Resonance Imaging methods, Hippocampus diagnostic imaging, Temporal Lobe, Seizures, Epilepsy, Temporal Lobe diagnosis
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Objective: Temporal lobe epilepsy (TLE) is the most common pharmacoresistant epilepsy in adults. Here we profiled local neural function in TLE in vivo, building on prior evidence that has identified widespread structural alterations. Using resting-state functional magnetic resonance imaging (rs-fMRI), we mapped the whole-brain intrinsic neural timescales (INT), which reflect temporal hierarchies of neural processing. Parallel analysis of structural and diffusion MRI data examined associations with TLE-related structural compromise. Finally, we evaluated the clinical utility of INT., Methods: We studied 46 patients with TLE and 44 healthy controls from two independent sites, and mapped INT changes in patients relative to controls across hippocampal, subcortical, and neocortical regions. We examined region-specific associations to structural alterations and explored the effects of age and epilepsy duration. Supervised machine learning assessed the utility of INT for identifying patients with TLE vs controls and left- vs right-sided seizure onset., Results: Relative to controls, TLE showed marked INT reductions across multiple regions bilaterally, indexing faster changing resting activity, with strongest effects in the ipsilateral medial and lateral temporal regions, and bilateral sensorimotor cortices as well as thalamus and hippocampus. Findings were similar, albeit with reduced effect sizes, when correcting for structural alterations. INT reductions in TLE increased with advancing disease duration, yet findings differed from the aging effects seen in controls. INT-derived classifiers discriminated patients vs controls (balanced accuracy, 5-fold: 76% ± 2.65%; cross-site, 72%-83%) and lateralized the focus in TLE (balanced accuracy, 5-fold: 96% ± 2.10%; cross-site, 95%-97%), with high accuracy and cross-site generalizability. Findings were consistent across both acquisition sites and robust when controlling for motion and several methodological confounds., Significance: Our findings demonstrate atypical macroscale function in TLE in a topography that extends beyond mesiotemporal epicenters. INT measurements can assist in TLE diagnosis, seizure focus lateralization, and monitoring of disease progression, which emphasizes promising clinical utility., (© 2023 The Authors. Epilepsia published by Wiley Periodicals LLC on behalf of International League Against Epilepsy.)
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- 2023
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36. Meningioma resection and venous thromboembolism incidence, management, and outcomes.
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Rizzo SM, Tavakol S, Bi WL, Li S, Secemsky EA, Campia U, Piazza G, Goldhaber SZ, and Schmaier AA
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Background: Meningioma resection is associated with the risk of venous thromboembolism (VTE)., Objectives: To determine the incidence and risk factors for VTE following meningioma resection and VTE outcomes based on the type and timing of anticoagulation., Methods: From 2011 to 2019, 901 consecutive patients underwent meningioma resection. We retrospectively evaluated the postoperative incidence of VTE and bleeding. For VTE, we determined the treatment strategy and rate of VTE complications and bleeding., Results: Pharmacologic prophylaxis was administered to 665 (73.8%) patients. The cumulative incidence for total postoperative VTE was 8.7% (95% CI: 6.9%-10.6%), and for symptomatic VTE was 6.0% (95% CI: 4.6%-7.7%). A multivariable model identified the following independent predictors of symptomatic VTE: history of VTE, obesity, and lack of pharmacologic prophylaxis. Following postoperative VTE, 58 (74.3%) patients received therapeutic anticoagulation either initially (33.3%) or after a median delay of 23.5 days (41.0%). Symptomatic recurrent VTE occurred in 13 (16.6%) patients. Following VTE, the use of subtherapeutic anticoagulation was associated with a lower rate of total VTE extension than no anticoagulation (17.5% vs 42.9%, OR 0.28, 95% CI: 0.09-0.93). In total, 14 patients (1.6%) experienced clinically relevant bleeding: 4 received therapeutic anticoagulants, 8 received prophylactic anticoagulation, and 2 received no anticoagulation. Among patients with VTE, 4 (5.1%) experienced bleeding., Conclusion: Recognition of risk factors for VTE following meningioma resection may help improve approaches to thromboprophylaxis. The management of postoperative VTE is highly variable, but most VTE patients are ultimately treated with therapeutic anticoagulants., (© 2023 The Author(s).)
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- 2023
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37. Long-range functional connections mirror and link microarchitectural and cognitive hierarchies in the human brain.
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Wang Y, Royer J, Park BY, Vos de Wael R, Larivière S, Tavakol S, Rodriguez-Cruces R, Paquola C, Hong SJ, Margulies DS, Smallwood J, Valk SL, Evans AC, and Bernhardt BC
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- Humans, Magnetic Resonance Imaging methods, Brain Mapping methods, Cognition, Emotions, Neural Pathways, Neocortex, Connectome methods
- Abstract
Background: Higher-order cognition is hypothesized to be implemented via distributed cortical networks that are linked via long-range connections. However, it is unknown how computational advantages of long-range connections reflect cortical microstructure and microcircuitry., Methods: We investigated this question by (i) profiling long-range cortical connectivity using resting-state functional magnetic resonance imaging (MRI) and cortico-cortical geodesic distance mapping, (ii) assessing how long-range connections reflect local brain microarchitecture, and (iii) examining the microarchitectural similarity of regions connected through long-range connections., Results: Analysis of 2 independent datasets indicated that sensory/motor areas had more clustered short-range connections, while transmodal association systems hosted distributed, long-range connections. Meta-analytical decoding suggested that this topographical difference mirrored shifts in cognitive function, from perception/action towards emotional/social processing. Analysis of myelin-sensitive in vivo MRI as well as postmortem histology and transcriptomics datasets established that gradients in functional connectivity distance are paralleled by those present in cortical microarchitecture. Notably, long-range connections were found to link spatially remote regions of association cortex with an unexpectedly similar microarchitecture., Conclusions: By mapping covarying topographies of long-range functional connections and cortical microcircuits, the current work provides insights into structure-function relations in human neocortex., (© The Author(s) 2022. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2023
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38. Dutasteride nanoemulsion preparation to inhibit 5-alpha-hair follicle reductase enzymes in the hair follicle; an ex vivo study.
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Memar Bashi Aval M, Hoveizi E, Mombeiny R, Kazemi M, Saeedi S, and Tavakol S
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- Animals, Rats, Dutasteride therapeutic use, 5-alpha Reductase Inhibitors pharmacology, 5-alpha Reductase Inhibitors therapeutic use, Alopecia drug therapy, Hair Follicle, Cholestenone 5 alpha-Reductase
- Abstract
Alopecia is a treatable disorder that usually occurs due to high levels of 5-alpha dihydrotestosterone in hair follicles. To enhance the storage capacity of hair follicles and alleviate the inherent characteristics of dutasteride, 5-alpha reductase inhibitor, a prolonged-release nanocarrier was synthesised, and its influence on rat abdomen's skin was investigated. Results showed the lower ratio of S/Co (higher ethanol concentration) increased the hydrodynamic nanocarriers' particle size due to thermodynamic disturbance and Ostwald ripening. In contrast, an increase in surfactant through a decrease in interfacial tension resulted in smaller nanocarriers of 32.4 nm. Moreover, an increase in viscosity had an inverse correlation with the nanoemulsions' particle size. Nanocarriers containing ethanol showed less entrapment efficacy, perhaps due to the rapid dissolution of dutasteride into ethanol during nanoemulsification, while, based on Stokes' equation, the addition of ethanol resulted in smaller particle size and stability of the system. Skin permeation analysis using Franz diffusion cells showed nanocarriers could pass through the skin and release dutasteride for 6 days. In conclusion, the optimum concentration of ingredients is decisive in guaranteeing the ideal particle size, stability, and skin permeation of nanocarriers. The Present dutasteride nanocarrier would promise a prolonged and sustained-release drug delivery system for Alopecia therapy., (© 2022 The Authors. IET Nanobiotechnology published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology.)
- Published
- 2023
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39. The Twofold Role of Osteogenic Small Molecules in Parkinson's Disease Therapeutics: Crosstalk of Osteogenesis and Neurogenesis.
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Tavakol S
- Subjects
- Aged, Humans, Osteogenesis, Substantia Nigra, Neurogenesis, Signal Transduction physiology, Dopaminergic Neurons, Ubiquitin-Protein Ligases metabolism, Parkinson Disease drug therapy, Parkinson Disease metabolism
- Abstract
Deemed one of the most problematic neurodegenerative diseases in the elderly population, Parkinson's disease remains incurable to date. Ongoing diagnostic studies, however, have revealed that a large number of small molecule drugs that trigger the BMP2-Smad signaling pathway with an osteogenic nature may be effective in Parkinson's disease treatment. Although BMP2 and Smad1, 3, and 5 biomolecules promote neurite outgrowth and neuroprotection in dopaminergic cells as well, small molecules are quicker at crossing the BBB and reaching the damaged dopaminergic neurons located in the substantia nigra due to a molecular weight less than 500 Da. It is worth noting that osteogenic small molecules that inhibit Smurf1 phosphorylation do not offer therapeutic opportunities for Parkinson's disease; whereas, osteogenic small molecules that trigger Smad1, 3, and 5 phosphorylation may have strong therapeutic implications in Parkinson's disease by increasing the survival rate of dopaminergic cells and neuritogenesis. Notably, from a different perspective, it might be said that osteogenic small molecules can possibly put forth therapeutic options for Parkinson's disease by improving neuritogenesis and cell survival., Competing Interests: The author indicates no potential conflicts of interest., (Copyright © 2022 Shima Tavakol.)
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- 2022
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40. Dual role of quercetin in enhancing the efficacy of cisplatin in chemotherapy and protection against its side effects: a review.
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Najafi M, Tavakol S, Zarrabi A, and Ashrafizadeh M
- Subjects
- Humans, Cisplatin adverse effects, Quercetin pharmacology, Quercetin therapeutic use, Antineoplastic Agents adverse effects, Neoplasms drug therapy
- Abstract
Chemotherapy has opened a new window in cancer therapy. However, the resistance of cancer cells has dramatically reduced the efficacy of chemotherapy. Cisplatin is a chemotherapeutic agent and its potential in cancer therapy has been restricted by resistance of cancer cells. As a consequence, the scientists have attempted to find new strategies in elevating chemotherapy efficacy. Due to great anti-tumour activity, naturally occurring compounds are of interest in polychemotherapy. Quercetin is a flavonoid with high anti-tumour activity against different cancers that can be used with cisplatin to enhance its efficacy and also are seen to sensitise cancer cells into chemotherapy. Furthermore, cisplatin has side effects such as nephrotoxicity and ototoxicity. Administration of quercetin is advantageous in reducing the adverse effects of cisplatin without compromising its anti-tumour activity. In this review, we investigate the dual role of quercetin in enhancing anti-tumour activity of cisplatin and simultaneous reduction in its adverse effects.
- Published
- 2022
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41. Modulation of autophagy by melatonin via sirtuins in stroke: From mechanisms to therapies.
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Azedi F, Tavakol S, Ketabforoush AHME, Khazaei G, Bakhtazad A, Mousavizadeh K, and Joghataei MT
- Subjects
- Antioxidants metabolism, Antioxidants pharmacology, Antioxidants therapeutic use, Apoptosis, Autophagy, Humans, Oxidative Stress, Melatonin metabolism, Melatonin pharmacology, Melatonin therapeutic use, Sirtuins metabolism, Stroke drug therapy
- Abstract
Sirtuins perform an important effect on the neural cell fate following stroke. Several mechanisms that have been correlated with stroke are oxidative stress, apoptosis, necrosis and autophagy. Autophagy is usually regarded as unitary of the neural cell survival mechanisms. Recently, the importance of the sirtuins effect on autophagy by antioxidant agents for stroke treatment mentioned in various studies. One of these agents is melatonin. Melatonin can modulate autophagy by changing on sirtuin pathways. Melatonin and its metabolites adjust various sirtuins pathways related to apoptosis, proliferation, metastases, autophagy and inflammation in case of stroke. In this review, we will discuss about the modulation of autophagy by melatonin via sirtuins in stroke., Competing Interests: Declaration of competing interest None., (Copyright © 2022. Published by Elsevier Inc.)
- Published
- 2022
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42. An Open MRI Dataset For Multiscale Neuroscience.
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Royer J, Rodríguez-Cruces R, Tavakol S, Larivière S, Herholz P, Li Q, Vos de Wael R, Paquola C, Benkarim O, Park BY, Lowe AJ, Margulies D, Smallwood J, Bernasconi A, Bernasconi N, Frauscher B, and Bernhardt BC
- Subjects
- Adult, Canada, Diffusion Magnetic Resonance Imaging, Female, Humans, Male, Connectome, Neuroimaging methods
- Abstract
Multimodal neuroimaging grants a powerful window into the structure and function of the human brain at multiple scales. Recent methodological and conceptual advances have enabled investigations of the interplay between large-scale spatial trends (also referred to as gradients) in brain microstructure and connectivity, offering an integrative framework to study multiscale brain organization. Here, we share a multimodal MRI dataset for Microstructure-Informed Connectomics (MICA-MICs) acquired in 50 healthy adults (23 women; 29.54 ± 5.62 years) who underwent high-resolution T1-weighted MRI, myelin-sensitive quantitative T1 relaxometry, diffusion-weighted MRI, and resting-state functional MRI at 3 Tesla. In addition to raw anonymized MRI data, this release includes brain-wide connectomes derived from (i) resting-state functional imaging, (ii) diffusion tractography, (iii) microstructure covariance analysis, and (iv) geodesic cortical distance, gathered across multiple parcellation scales. Alongside, we share large-scale gradients estimated from each modality and parcellation scale. Our dataset will facilitate future research examining the coupling between brain microstructure, connectivity, and function. MICA-MICs is available on the Canadian Open Neuroscience Platform data portal ( https://portal.conp.ca ) and the Open Science Framework ( https://osf.io/j532r/ )., (© 2022. The Author(s).)
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- 2022
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43. Fingolimod Nanoemulsions at Different Particle Sizes Define the Fate of Spinal Cord Injury Recovery.
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Poormoghadam D, Shiadeh BR, Azedi F, Tavakol H, Rezayat SM, and Tavakol S
- Subjects
- Animals, Delayed-Action Preparations pharmacology, Endothelial Cells, Particle Size, Rats, Spinal Cord metabolism, Fingolimod Hydrochloride pharmacology, Spinal Cord Injuries metabolism
- Abstract
Spinal cord injury (SCI) is a debilitating condition for which no definitive treatment has yet been identified. Notably, it influences other tissues through inflammatory reactions and metabolic disturbances. Therefore, fingolimod (FTY-720), as an FDA-approved inflammatory modulator, would be promising. In the present study, nanocarriers with two distinct monodisperse particle sizes of 60 (nF60) and 190 (nF190) nm were prepared via low-(stirring) and high-energy (probe ultrasound) emulsion oil in water (O/W) methods. Larger nanocarriers showed higher EE% and sustained-release profile than smaller nanocarriers. Neural stem cell (NSC) viability and lactate dehydrogenase (LDH) release were studied in the presence of nanocarriers and free FTY-720. The results indicated that nanocarriers and free FTY-720 enhanced NSC viability compared with the control group. However, nF190 induced significantly less cell membrane damage than nF60. Nanocarriers and free FTY-720 enhanced motor neuron recovery in SCI rats, while body weight and return to bladder reflux by nF190 were significantly higher than those in the nF60 group. Return to bladder reflux might be due to the role of FTY-720 in the regulation of detrusor muscle tone and preservation of the integrity of vessels by acting on endothelial cells. Moreover, nF190 gained higher soleus muscle weight than the free drugs; probably decreasing proinflammatory cytokines in the soleus diminishes muscular atrophy in SCI rats. In summary, it might be said that larger nanocarriers with sustained-release profile and less cell membrane damage seem to be more efficient than smaller ones to manage SCI and enhance bladder reflux. These data will help pharmaceutical companies select the correct particle size for nanodrugs and develop more efficient drug formulations to treat SCI., Competing Interests: The authors declare no competing interests., (Copyright © 2022 Delaram Poormoghadam et al.)
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- 2022
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44. Epidural electrical stimulation of the cervical spinal cord opposes opioid-induced respiratory depression.
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Huang R, Worrell J, Garner E, Wang S, Homsey T, Xu B, Galer EL, Zhou Y, Tavakol S, Daneshvar M, Le T, Vinters HV, Salamon N, McArthur DL, Nuwer MR, Wu I, Leiter JC, and Lu DC
- Subjects
- Analgesics, Opioid adverse effects, Apnea, Electric Stimulation methods, Humans, Remifentanil, Spinal Cord physiology, Cervical Cord, Respiratory Insufficiency chemically induced, Respiratory Insufficiency therapy, Spinal Cord Injuries
- Abstract
Opioid overdose suppresses brainstem respiratory circuits, causes apnoea and may result in death. Epidural electrical stimulation (EES) at the cervical spinal cord facilitated motor activity in rodents and humans, and we hypothesized that EES of the cervical spinal cord could antagonize opioid-induced respiratory depression in humans. Eighteen patients requiring surgical access to the dorsal surface of the spinal cord between C2 and C7 received EES or sham stimulation for up to 90 s at 5 or 30 Hz during complete (OFF-State) or partial suppression (ON-State) of respiration induced by remifentanil. During the ON-State, 30 Hz EES at C4 and 5 Hz EES at C3/4 increased tidal volume and decreased the end-tidal carbon dioxide level compared to pre-stimulation control levels. EES of 5 Hz at C5 and C7 increased respiratory frequency compared to pre-stimulation control levels. In the OFF-State, 30 Hz cervical EES at C3/4 terminated apnoea and induced rhythmic breathing. In cadaveric tissue obtained from a brain bank, more neurons expressed both the neurokinin 1 receptor (NK1R) and somatostatin (SST) in the cervical spinal levels responsive to EES (C3/4, C6 and C7) compared to a region non-responsive to EES (C2). Thus, the capacity of cervical EES to oppose opioid depression of respiration may be mediated by NK1R+/SST+ neurons in the dorsal cervical spinal cord. This study provides proof of principle that cervical EES may provide a novel therapeutic approach to augment respiratory activity when the neural function of the central respiratory circuits is compromised by opioids or other pathological conditions. KEY POINTS: Epidural electrical stimulation (EES) using an implanted spinal cord stimulator (SCS) is an FDA-approved method to manage chronic pain. We tested the hypothesis that cervical EES facilitates respiration during administration of opioids in 18 human subjects who were treated with low-dose remifentanil that suppressed respiration (ON-State) or high-dose remifentanil that completely inhibited breathing (OFF-State) during the course of cervical surgery. Dorsal cervical EES of the spinal cord augmented the respiratory tidal volume or increased the respiratory frequency, and the response to EES varied as a function of the stimulation frequency (5 or 30 Hz) and the cervical level stimulated (C2-C7). Short, continuous cervical EES restored a cyclic breathing pattern (eupnoea) in the OFF-State, suggesting that cervical EES reversed the opioid-induced respiratory depression. These findings add to our understanding of respiratory pattern modulation and suggest a novel mechanism to oppose the respiratory depression caused by opioids., (© 2022 The Authors. The Journal of Physiology © 2022 The Physiological Society.)
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- 2022
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45. Vitamin E at a high dose as an anti-ferroptosis drug and not just a supplement for COVID-19 treatment.
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Tavakol S and Seifalian AM
- Subjects
- Dietary Supplements, Humans, Iron, Vitamin E therapeutic use, COVID-19 Drug Treatment
- Published
- 2022
- Full Text
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46. Topographic divergence of atypical cortical asymmetry and atrophy patterns in temporal lobe epilepsy.
- Author
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Park BY, Larivière S, Rodríguez-Cruces R, Royer J, Tavakol S, Wang Y, Caciagli L, Caligiuri ME, Gambardella A, Concha L, Keller SS, Cendes F, Alvim MKM, Yasuda C, Bonilha L, Gleichgerrcht E, Focke NK, Kreilkamp BAK, Domin M, von Podewils F, Langner S, Rummel C, Rebsamen M, Wiest R, Martin P, Kotikalapudi R, Bender B, O'Brien TJ, Law M, Sinclair B, Vivash L, Kwan P, Desmond PM, Malpas CB, Lui E, Alhusaini S, Doherty CP, Cavalleri GL, Delanty N, Kälviäinen R, Jackson GD, Kowalczyk M, Mascalchi M, Semmelroch M, Thomas RH, Soltanian-Zadeh H, Davoodi-Bojd E, Zhang J, Lenge M, Guerrini R, Bartolini E, Hamandi K, Foley S, Weber B, Depondt C, Absil J, Carr SJA, Abela E, Richardson MP, Devinsky O, Severino M, Striano P, Parodi C, Tortora D, Hatton SN, Vos SB, Duncan JS, Galovic M, Whelan CD, Bargalló N, Pariente J, Conde-Blanco E, Vaudano AE, Tondelli M, Meletti S, Kong XZ, Francks C, Fisher SE, Caldairou B, Ryten M, Labate A, Sisodiya SM, Thompson PM, McDonald CR, Bernasconi A, Bernasconi N, and Bernhardt BC
- Subjects
- Adult, Atrophy pathology, Hippocampus pathology, Humans, Magnetic Resonance Imaging, Connectome, Epilepsy, Temporal Lobe pathology
- Abstract
Temporal lobe epilepsy, a common drug-resistant epilepsy in adults, is primarily a limbic network disorder associated with predominant unilateral hippocampal pathology. Structural MRI has provided an in vivo window into whole-brain grey matter structural alterations in temporal lobe epilepsy relative to controls, by either mapping (i) atypical inter-hemispheric asymmetry; or (ii) regional atrophy. However, similarities and differences of both atypical asymmetry and regional atrophy measures have not been systematically investigated. Here, we addressed this gap using the multisite ENIGMA-Epilepsy dataset comprising MRI brain morphological measures in 732 temporal lobe epilepsy patients and 1418 healthy controls. We compared spatial distributions of grey matter asymmetry and atrophy in temporal lobe epilepsy, contextualized their topographies relative to spatial gradients in cortical microstructure and functional connectivity calculated using 207 healthy controls obtained from Human Connectome Project and an independent dataset containing 23 temporal lobe epilepsy patients and 53 healthy controls and examined clinical associations using machine learning. We identified a marked divergence in the spatial distribution of atypical inter-hemispheric asymmetry and regional atrophy mapping. The former revealed a temporo-limbic disease signature while the latter showed diffuse and bilateral patterns. Our findings were robust across individual sites and patients. Cortical atrophy was significantly correlated with disease duration and age at seizure onset, while degrees of asymmetry did not show a significant relationship to these clinical variables. Our findings highlight that the mapping of atypical inter-hemispheric asymmetry and regional atrophy tap into two complementary aspects of temporal lobe epilepsy-related pathology, with the former revealing primary substrates in ipsilateral limbic circuits and the latter capturing bilateral disease effects. These findings refine our notion of the neuropathology of temporal lobe epilepsy and may inform future discovery and validation of complementary MRI biomarkers in temporal lobe epilepsy., (© The Author(s) (2021). Published by Oxford University Press on behalf of the Guarantors of Brain.)
- Published
- 2022
- Full Text
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47. Dexamethasone: Insights into Pharmacological Aspects, Therapeutic Mechanisms, and Delivery Systems.
- Author
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Madamsetty VS, Mohammadinejad R, Uzieliene I, Nabavi N, Dehshahri A, García-Couce J, Tavakol S, Moghassemi S, Dadashzadeh A, Makvandi P, Pardakhty A, Aghaei Afshar A, and Seyfoddin A
- Subjects
- Dexamethasone pharmacology, Dexamethasone therapeutic use, Drug Delivery Systems, Humans, Nanoparticles therapeutic use, COVID-19 Drug Treatment
- Abstract
Dexamethasone (DEX) has been widely used to treat a variety of diseases, including autoimmune diseases, allergies, ocular disorders, cancer, and, more recently, COVID-19. However, DEX usage is often restricted in the clinic due to its poor water solubility. When administered through a systemic route, it can elicit severe side effects, such as hypertension, peptic ulcers, hyperglycemia, and hydro-electrolytic disorders. There is currently much interest in developing efficient DEX-loaded nanoformulations that ameliorate adverse disease effects inhibiting advancements in scientific research. Various nanoparticles have been developed to selectively deliver drugs without destroying healthy cells or organs in recent years. In the present review, we have summarized some of the most attractive applications of DEX-loaded delivery systems, including liposomes, polymers, hydrogels, nanofibers, silica, calcium phosphate, and hydroxyapatite. This review provides our readers with a broad spectrum of nanomedicine approaches to deliver DEX safely.
- Published
- 2022
- Full Text
- View/download PDF
48. A molecularly integrated grade for meningioma.
- Author
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Driver J, Hoffman SE, Tavakol S, Woodward E, Maury EA, Bhave V, Greenwald NF, Nassiri F, Aldape K, Zadeh G, Choudhury A, Vasudevan HN, Magill ST, Raleigh DR, Abedalthagafi M, Aizer AA, Alexander BM, Ligon KL, Reardon DA, Wen PY, Al-Mefty O, Ligon AH, Dubuc AM, Beroukhim R, Claus EB, Dunn IF, Santagata S, and Bi WL
- Subjects
- Adult, Cohort Studies, Humans, Neoplasm Grading, Neoplasm Recurrence, Local genetics, Prognosis, Retrospective Studies, World Health Organization, Meningeal Neoplasms pathology, Meningioma pathology
- Abstract
Background: Meningiomas are the most common primary intracranial tumor in adults. Clinical care is currently guided by the World Health Organization (WHO) grade assigned to meningiomas, a 3-tiered grading system based on histopathology features, as well as extent of surgical resection. Clinical behavior, however, often fails to conform to the WHO grade. Additional prognostic information is needed to optimize patient management., Methods: We evaluated whether chromosomal copy-number data improved prediction of time-to-recurrence for patients with meningioma who were treated with surgery, relative to the WHO schema. The models were developed using Cox proportional hazards, random survival forest, and gradient boosting in a discovery cohort of 527 meningioma patients and validated in 2 independent cohorts of 172 meningioma patients characterized by orthogonal genomic platforms., Results: We developed a 3-tiered grading scheme (Integrated Grades 1-3), which incorporated mitotic count and loss of chromosome 1p, 3p, 4, 6, 10, 14q, 18, 19, or CDKN2A. 32% of meningiomas reclassified to either a lower-risk or higher-risk Integrated Grade compared to their assigned WHO grade. The Integrated Grade more accurately identified meningioma patients at risk for recurrence, relative to the WHO grade, as determined by time-dependent area under the curve, average precision, and the Brier score., Conclusion: We propose a molecularly integrated grading scheme for meningiomas that significantly improves upon the current WHO grading system in prediction of progression-free survival. This framework can be broadly adopted by clinicians with relative ease using widely available genomic technologies and presents an advance in the care of meningioma patients., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Neuro-Oncology.)
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- 2022
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49. Differentiation of Human Wharton's Jelly Mesenchymal Stem Cells into SOX17 Expressing Cells Using a Wnt/ß-catenin Pathway Agonist on Polylactic Acid/Chitosan Nanocomposite Scaffold.
- Author
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Hoveizi E and Tavakol SH
- Abstract
Objective: The β-catenin signaling pathway promises the potential for differentiation of stem cells into definitive endoderm (DE) cells as precursors of beta cells. Therefore, it can be considered as an inducer for cell replacement therapies in diabetes. The main goal of this research is to successfully culture and induce differentiation of human Wharton's jelly mesenchymal stem cells (hWJMSCs) into Sox17-expressing cells using a Wnt/β-catenin pathway agonist (SKL2001) plus nanoparticles on a polylactic acid/chitosan (PLA/Cs) nanocomposite scaffold., Materials and Methods: In this experimental study, the nanocomposite was prepared through an electrospinning method and hWJMSCs were isolated through an explant technique. The morphology and the cell viability were evaluated by scanning electron microscopy (SEM) and 3-(4, 5- Dimethylthiazol-2)-2, 5-diphenyltetrazolium bromide (MTT) assay. Here, we present two differentiation protocols: the first one is induction with SKL2001; and the second one is with a combination of SKL2001 and zinc oxide nanoparticles (nZnO). Real-time quantitative reverse transcription (QRT-PCR) and immunocytochemistry analysis are carried out to examine the expression of specific markers in the differentiated cells., Results: The nanocomposite had appropriate biocompatibility for cell adhesion and growth. While the hWJMSCs cultured on the PLA/Cs scaffolds differentiated into DE cells in the presence of SKL2001, introducing nZnO to their environment increased the differentiation process. Analyses of DE-specific markers including SOX17, FOXA2 , and gooscoid (GSC) genes in mRNA level, indicated significantly high levels of expression in the SKL2001/nZnO group, followed by SKL2001 group compared to the control., Conclusion: Our results show the beneficial effects of the Wnt/β-catenin pathway agonist in three-dimensional (3D) cultures in cell replacement therapy for diabetes., Competing Interests: There is no conflict of interest in this study., (Copyright© by Royan Institute. All rights reserved.)
- Published
- 2022
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50. The World Against Versatile SARS-Cov-2 Nanomachines: Mythological or Reality?
- Author
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Tavakol S, Tavakol H, Alavijeh MS, and Seifalian A
- Subjects
- Aged, Humans, Lung, COVID-19, SARS-CoV-2
- Abstract
Nanomachines hold promise for the next generation of emerging technology; however, nanomachines are not a new concept. Viruses, nature's nanomachines, have already existed for thousands of years. In 2019, the whole world had to come together to confront a life-threatening nanomachine named "SARS-CoV-2", which causes COVID-19 illness. SARS-CoV-2, a smart nanomachine, attaches itself to the ACE2 and CD147 receptors present on the cell surfaces of the lungs, kidneys, heart, brain, intestines, testes, etc. and triggers pathogenesis. Cell entry triggers a cascade of inflammatory responses resulting in tissue damage, with the worst affected cases leading to death. SARS-CoV-2 influences several receptors and signalling pathways; therefore, finding a biomaterial that caps these signalling pathways and ligand sites is of interest. This research aimed to compare the similarities and differences between COVID-19 and its elderly sisters, MERS and SARS. Furthermore, we glanced at emerging therapeutics that carry potential in eliminating SARS-CoV-2, and the tissue damage it causes. Simple prophylactic and therapeutic strategies for the treatment of COVID- 19 infection have been put forward., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
- Published
- 2022
- Full Text
- View/download PDF
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