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Asif Jamil Giorgi Batsikadze Hsiao‐I. Kuo Raf L. J. Meesen Peter Dechent Walter Paulus Michael A. Nitsche 《Human brain mapping》2020,41(6):1644-1666
Transcranial direct current stimulation (tDCS) induces polarity‐ and dose‐dependent neuroplastic aftereffects on cortical excitability and cortical activity, as demonstrated by transcranial magnetic stimulation (TMS) and functional imaging (fMRI) studies. However, lacking systematic comparative studies between stimulation‐induced changes in cortical excitability obtained from TMS, and cortical neurovascular activity obtained from fMRI, prevent the extrapolation of respective physiological and mechanistic bases. We investigated polarity‐ and intensity‐dependent effects of tDCS on cerebral blood flow (CBF) using resting‐state arterial spin labeling (ASL‐MRI), and compared the respective changes to TMS‐induced cortical excitability (amplitudes of motor evoked potentials, MEP) in separate sessions within the same subjects (n = 29). Fifteen minutes of sham, 0.5, 1.0, 1.5, and 2.0‐mA anodal or cathodal tDCS was applied over the left primary motor cortex (M1) in a randomized repeated‐measure design. Time‐course changes were measured before, during and intermittently up to 120‐min after stimulation. ROI analyses indicated linear intensity‐ and polarity‐dependent tDCS after‐effects: all anodal‐M1 intensities increased CBF under the M1 electrode, with 2.0‐mA increasing CBF the greatest (15.3%) compared to sham, while all cathodal‐M1 intensities decreased left M1 CBF from baseline, with 2.0‐mA decreasing the greatest (?9.3%) from sham after 120‐min. The spatial distribution of perfusion changes correlated with the predicted electric field, as simulated with finite element modeling. Moreover, tDCS‐induced excitability changes correlated more strongly with perfusion changes in the left sensorimotor region compared to the targeted hand‐knob region. Our findings reveal lasting tDCS‐induced alterations in cerebral perfusion, which are dose‐dependent with tDCS parameters, but only partially account for excitability changes. 相似文献
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Hielke M. de Vries Hack Jae Lee Wayne Lam Rosa S. Djajadiningrat Sarah R. Ottenhof Eduard Roussel Bin Klaas Kroon Igle Jan de Jong Pedro Oliveira Hussain M. Alnajjar Maarten Albersen Asif Muneer Vijay Sangar Arie Parnham Benjamin Ayres Nick Watkin Simon Horenblas Martijn M. Stuiver Oscar R. Brouwer 《BJU international》2022,130(1):126-132
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Tahir Yaqub Muhammad Nawaz Muhammad Z. Shabbir Muhammad A. Ali Imran Altaf Sohail Raza Muhammad A. B. Shabbir Muhammad A. Ashraf Syed Z. Aziz Sohail Q. Cheema Muhammad B. Shah Saira Rafique Sohail Hassan Nageen Sardar Adnan Mehmood Muhammad W. Aziz Sehar Fazal Nadir Hussain Muhammad T. Khan Muhammad M. Atique Ali Asif Muhammad Anwar Nabeel A. Awan Muhammad U. Younis Muhammad A. Bhattee Zarfishan Tahir Nadia Mukhtar Huda Sarwar Maaz S. Rana Omair Farooq 《Biomedical and environmental sciences : BES》2021,34(9):729-733
In 2019, the newly emerged SARS-CoV-2 virus caused pneumonia-like illness. The disease rapidly spread globally, leading to a worldwide outbreak referred to as the COVID-19 pandemic. The affected patients show symptoms of fever, dry cough, respiratory distress, myalgia, and gastrointestinal disturbance. As of April 5, 2021, 132,083,022 people worldwide were affected by COVID-19, while 2,868,454 people died due to the disease[1]. SARS-CoV-2-positive patients may remain asymptomatic or start showing symptoms in 2?14 days after exposure to the virus[2]. The viral infection can be diagnosed from nasopharyngeal, throat, alveolar lavage, lacrimal, blood, and stool samples. The patient starts shedding the virus in stool regardless of being symptomatic or asymptomatic, which makes sewage-based detection of the virus to be more beneficial in the early infection stage. 相似文献
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