Abstract:
:Transcranial direct current stimulation (tDCS) is used in numerous clinical studies and considered an effective and versatile add-on therapy in neurorehabilitation. To date, however, the underlying neurobiological mechanisms remain elusive. In a rat model of tDCS, we recently observed a polarity-dependent accumulation of endogenous neural stem cells (NSCs) in the stimulated cortex. Based upon these findings, we hypothesized that tDCS may exert a direct migratory effect on endogenous NSCs towards the stimulated cortex. Using noninvasive imaging, we here investigated whether tDCS may also cause a directed migration of engrafted NSCs. Murine NSCs were labeled with superparamagnetic particles of iron oxide (SPIOs) and implanted into rat striatum and corpus callosum. MRI was performed (i) immediately after implantation and (ii) after 10 tDCS sessions of anodal or cathodal polarity. Sham-stimulated rats served as control. Imaging results were validated ex vivo using immunohistochemistry. Overall migratory activity of NSCs almost doubled after anodal tDCS. However, no directed migration within the electric field (i.e. towards or away from the electrode) could be observed. Rather, an undirected outward migration from the center of the graft was detected. Xenograft transplantation induced a neuroinflammatory response that was significantly enhanced following cathodal tDCS. This inflammatory response did not impact negatively on the survival of implanted NSCs. Data suggest that anodal tDCS increases the undirected migratory activity of implanted NSCs. Since the electric field did not guide implanted NSCs over large distances, previously observed polarity-dependent accumulation of endogenous NSCs in the cortex might have originated from local proliferation. Results enhance our understanding of the neurobiological mechanisms underlying tDCS, and may thereby help to develop a targeted and sustainable application of tDCS in clinical practice.
journal_name
NMR Biomedjournal_title
NMR in biomedicineauthors
Keuters MH,Aswendt M,Tennstaedt A,Wiedermann D,Pikhovych A,Rotthues S,Fink GR,Schroeter M,Hoehn M,Rueger MAdoi
10.1002/nbm.3244subject
Has Abstractpub_date
2015-02-01 00:00:00pages
231-9issue
2eissn
0952-3480issn
1099-1492journal_volume
28pub_type
杂志文章abstract::Blood flow and phosphorus metabolites have been measured simultaneously in the murine RIF-1 tumour in vivo. Blood flow was measured using the H2 washout technique and 31P NMR spectroscopy was used to measure high energy phosphates, inorganic phosphate and intracellular pH within the tumour. Following NMR and flow meas...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940030406
更新日期:1990-08-01 00:00:00
abstract::Dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) and proton (1H) magnetic resonance spectroscopy (MRS) provide structural and biochemical information, including vascular volume, vascular permeability and tissue metabolism. In this study, we performed analysis of the enhancement characteristic from DCE-...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1511
更新日期:2010-10-01 00:00:00
abstract::In vitro (1)H MRS of human bile has shown potential in the diagnosis of various hepatopancreatobiliary (HPB) diseases. Previously, in vivo (1)H MRS of human bile in gallbladder using a 1.5 T scanner demonstrated the possibility of quantification of choline-containing phospholipids (chol-PLs). However, other lipid comp...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3173
更新日期:2014-10-01 00:00:00
abstract::We have developed a reliable, reproducible model of hypoxia in the gerbil. 1H and 31P NMR spectroscopy demonstrates that cerebral energy metabolism is very resistant to hypoxia. Cerebral blood flow (measured by hydrogen clearance) began to increase when the arterial oxygen tension (paO2) was reduced to 40-50 mm Hg, an...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940050109
更新日期:1992-01-01 00:00:00
abstract::Diffusion measurements were performed on the N-acetyl aspartate (NAA) signal in in situ brains (in vivo and post-mortem) and on in vitro brain tissue at 37 degrees C using wide ranges of b-values (from 0 up to 4.5 x 10(6) s/cm2 and 35.8 x 10(6) s/cm2 for the in vivo and the in vitro cases, respectively). In vivo and i...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(sici)1099-1492(199804)11:2<67::aid-nbm503
更新日期:1998-04-01 00:00:00
abstract::This paper describes the development of a novel technique for functional MRI of the human brain at 0.135 microL resolution for a whole brain section. In comparison with conventional studies at 3 mm isotropic resolution or 27 microL voxel size, the method yields an improvement by a factor of 200. To achieve optimum ima...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.998
更新日期:2005-12-01 00:00:00
abstract::An often-employed strategy to enhance signals in (31) P MRS is the generation of the nuclear Overhauser effect (NOE) by saturation of the water resonance. However, NOE allegedly increases the variability of the (31) P data, because variation is reported in NOE enhancements. This would negate the signal-to-noise (SNR) ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3455
更新日期:2016-03-01 00:00:00
abstract::Prader-Willi syndrome (PWS) is a genetic imprinting disorder characterized mainly by hyperphagia and early childhood obesity. Previous functional neuroimaging studies used visual stimuli to examine abnormal activities in the eating-related neural circuitry of patients with PWS. It was found that patients with PWS exhi...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2900
更新日期:2013-06-01 00:00:00
abstract::Balanced steady-state free precession imaging has recently been suggested for chemical exchange detection (bSSFPX). The objective of this work is to investigate the contributions of microstructural, chemical shift and chemical exchange effects to the asymmetry of the bSSFP profile at field strengths of 3 T and 9.4 T. ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4200
更新日期:2020-03-01 00:00:00
abstract::In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 9 sections: 1 Books, Re...
journal_title:NMR in biomedicine
pub_type:
doi:10.1002/nbm.667
更新日期:2001-02-01 00:00:00
abstract::This study investigated the association between the total choline (tCho) concentration and the clinical characteristics and biomarker status of breast cancer. Sixty-two patients with breast cancer, 1.5 cm or larger in size on MR images, were studied. The tCho concentration was correlated with the MRI features, contra...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1595
更新日期:2011-04-01 00:00:00
abstract::Q-ball imaging (QBI) is an imaging technique that is capable of resolving intravoxel fiber crossings; however, the signal readout based on echo-planar imaging (EPI) introduces geometric distortions in the presence of susceptibility gradients. This study proposes an imaging technique that reduces susceptibility distort...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3009
更新日期:2013-12-01 00:00:00
abstract::Cross-talk between adipose tissue and liver is disturbed in the metabolic syndrome. Moreover, the relative fatty acid composition of adipose and liver fat is poorly characterized. Long-TE (1)H MRS can determine the unsaturation and polyunsaturation of adipose tissue. The aim of this study was to use long-TE (1)H MRS t...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1580
更新日期:2011-04-01 00:00:00
abstract::A special characteristic of the brain is the usage of lactate as alternative fuel instead of glucose to preserve its energy homeostasis. This physiological function is valid for sufficient cerebral glucose supply, as well as presumably during hypoglycemia, given that exogenous lactate infusion suppresses hormonal coun...
journal_title:NMR in biomedicine
pub_type: 杂志文章,随机对照试验
doi:10.1002/nbm.4167
更新日期:2019-11-01 00:00:00
abstract::Spin-exchange NMR techniques enable the measurement of the rates of exchange of solutes between chemically or physically distinct sites in reactions taking place at chemical equilibrium. The time scale of the events that are able to be investigated lies in the neighbourhood of 1 s. The earliest studies in this area of...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.1940030303
更新日期:1990-06-01 00:00:00
abstract::The transverse relaxation rates R2 and R2* were measured at 3 T in the substantia nigra of the midbrain of adult normal human controls. The relaxation rate arising from magnetic inhomogeneities, R2', was calculated from the relationship R2* = R2 + R2'. No significant differences were found for any parameters between l...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940080106
更新日期:1995-02-01 00:00:00
abstract::In this study the conjugated macromolecular ligand, diethylenetriaminepentaacetic acid (DTPA)-amide-dextran, was synthesized by attaching DTPA to the dextran macromolecule (M(r) approximately 6000) by a covalent amide bond. Subsequently, DTPA-amide-dextran was complexed with either of the two lanthanide metal ions dys...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940080404
更新日期:1995-06-01 00:00:00
abstract::One of the hallmarks of diffusion NMR and MRI is its ability to utilize restricted diffusion to probe compartments much smaller than the excited volume or the MRI voxel, respectively, and to extract microstructural information from them. Single-pulsed field gradient (s-PFG) MR methodologies have been employed with gre...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.1550
更新日期:2010-08-01 00:00:00
abstract::High grade and metastatic brain tumours exhibit considerable spatial variations in proliferation, angiogenesis, invasion, necrosis and oedema. Vascular heterogeneity arising from vascular co-option in regions of invasive growth (in which the blood-brain barrier remains intact) and neoangiogenesis is a major challenge ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3594
更新日期:2016-11-01 00:00:00
abstract::A short-echo spectroscopic imaging sequence extended with a frequency-selective multiple-quantum- coherence technique (Sel-MQC) is presented. The method enables acquisition of a complete water-suppressed proton spectrum with a short echo time and filtering of the J-coupling metabolite, lactate, from co-resonant lipids...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1284
更新日期:2008-11-01 00:00:00
abstract::There has been growing interest in understanding energy metabolism in human embryos generated using assisted reproductive techniques (ART) for improving the overall success rate of the method. Using NMR spectroscopy as a noninvasive tool, we studied human embryo metabolism to identify specific biomarkers to assess the...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2814
更新日期:2013-01-01 00:00:00
abstract::The aim of this study is to fabricate and test a novel flexible flat cable antenna (FFCA) for MRI of the knee at different flexion angles. The FFCA was made of a flat cable, a tuning/matching circuit and a signal transmission line. To test its feasibility and validity, in vitro and in vivo experiments were carried out...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3264
更新日期:2015-04-01 00:00:00
abstract::Results are presented from an in vivo study of human skin in which a zig-zag surface coil together with a three-pulse Fourier Series Window (FSW) protocol have been used to obtain minimally contaminated 31P skin spectra of the posterior calf. Phantom experiments indicate that while the fall-off in the B1 field profile...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(SICI)1099-1492(199608)9:5<195::AID-NBM416
更新日期:1996-08-01 00:00:00
abstract::Although diffusion MRI has shown promise for the characterization of breast cancer, it has low specificity to malignant subtypes. Higher specificity might be achieved if the effects of cell morphology and molecular exchange across cell membranes could be disentangled. The quantification of exchange might thus allow th...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3504
更新日期:2016-05-01 00:00:00
abstract::In this study, mapping of ultrashort T2 and T2* of acutely isolated porcine menisci at B0 = 9.4 T was investigated. Maps of T2 were measured from a slice through the pars intermedia with a spin echo-prepared two-dimensional ultrashort-TE T2 mapping technique published previously. T2* mapping was performed by two-dimen...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2931
更新日期:2013-09-01 00:00:00
abstract::13C MRS was installed on a clinical scanner at 1.5 T in order to facilitate integrated MR examinations of human brain disorders. Using a simplified protocol, (1-(13)C) glucose and/or (1-(13)C) acetate were administered orally or by intravenous infusion. (13)C spectra of diagnostic quality were acquired in more than 10...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.852
更新日期:2003-10-01 00:00:00
abstract::Diffusion tensor imaging (DTI) has been employed for over 2 decades to noninvasively quantify central nervous system diseases/injuries. However, DTI is an inadequate simplification of diffusion modeling in the presence of coexisting inflammation, edema and crossing nerve fibers. We employed a tissue phantom using fixe...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4414
更新日期:2021-01-01 00:00:00
abstract::During magnetic resonance imaging (MRI) examinations, the average specific absorption rate (SAR) of the whole body is calculated as an index of global energy deposition in biological tissue without taking into account the presence of metallic implants or conductive materials. However, this global SAR calculation is no...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3849
更新日期:2018-01-01 00:00:00
abstract::Polycystic kidney disease (PKD) is a life-threatening disease that leads to a grotesque enlargement of the kidney and significant loss of function. Several imaging studies with MRI have demonstrated that cyst size in polycystic kidneys can determine disease severity and progression. In the present study, we found that...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3281
更新日期:2015-05-01 00:00:00
abstract::The purpose of this work was to carry out diffusion tensor imaging (DTI) at multiple diffusion times Td in skeletal muscle in normal subjects and chronic exertional compartment syndrome (CECS) patients and analyze the data with the random permeable barrier model (RPBM) for biophysical specificity. Using an institution...
journal_title:NMR in biomedicine
pub_type: 临床试验,杂志文章
doi:10.1002/nbm.3087
更新日期:2014-05-01 00:00:00