Search results for "Diffusion"
showing 10 items of 1615 documents
Impaired anatomical connectivity and related executive functions: differentiating vulnerability and disease marker in bipolar disorder.
2012
Background Bipolar 1 disorder (BD1) has been associated with impaired set shifting, increased risk taking, and impaired integrity of frontolimbic white matter. However, it remains unknown to what extent these findings are related to each other and whether these abnormalities represent risk factors or consequences of the illness. Methods We addressed the first question by comparing 19 patients with BD1 and 19 healthy control subjects (sample 1) with diffusion tensor imaging, the Intra-Extra Dimensional Set Shift Task, and the Cambridge Gambling Task. The second question we approached by applying the same protocol to 22 healthy first-degree relatives of patients with BD1 and 22 persons withou…
Advanced magnetic resonance imaging of cortical laminar necrosis in patients with stroke
2019
Purpose The aim of this study was to assess the novel advanced magnetic resonance imaging findings of acute stage cortical laminar necrosis developing after complicated cardiovascular or abdominal surgery. Materials and methods This institutional review board-approved study included patients with postoperative stroke due to cortical laminar necrosis imaged with magnetic resonance in the acute stage. Brain magnetic resonance imaging examinations were obtained on a 3T magnetic resonance scanner within 48 hours of the neurological symptoms, including diffusion-weighted images (b value, 1000 s/mm2) and arterial spin labelling using a pseudo-continuous arterial spin labelling method in four pati…
Disturbed structural connectivity is related to inattention and impulsivity in adult attention deficit hyperactivity disorder
2010
Inattention and impulsivity are the most prominent clinical features of attention deficit hyperactivity disorder (ADHD) in adulthood. Structural and functional neuroimaging studies of subjects with ADHD have demonstrated abnormalities in several brain areas, including fronto-striatal and fronto-cerebellar networks. Mostly, these studies were based on volumetric measurements and have been conducted in children. We investigated white matter (WM) integrity and correlation with measures of attention and impulsivity in adult patients with ADHD adopting diffusion tensor imaging (DTI). N = 37 (21 males) never-medicated adult patients with ADHD combined subtype and N = 34 (16 males) healthy control…
Clinical aspects of the apparent diffusion coefficient in 3He MRI: results in healthy volunteers and patients after lung transplantation.
2007
Purpose To measure the apparent diffusion coefficient (ADC) after inhalation of hyperpolarized 3He in healthy volunteers and lung transplant recipients, and demonstrate the gravity dependence of ADC values. Materials and Methods Six healthy volunteers, 10 patients after single-lung transplantation, and six patients after double-lung transplantation were examined at 1.5T during inspiration and expiration. The inhalation of 300 mL of hyperpolarized 3He was performed with a computer-controlled delivery device. A two-dimensional fast low-angle shot (FLASH) sequence measured the 3He diffusive gas movement. From these data the ADC was calculated. Results The mean ADC was 0.143 cm2/second in healt…
Key issues in decomposing fMRI during naturalistic and continuous music experience with independent component analysis
2014
Background: Independent component analysis (ICA) has been often used to decompose fMRI data mostly for the resting-state, block and event-related designs due to its outstanding advantage. For fMRI data during free-listening experiences, only a few exploratory studies applied ICA.New method: For processing the fMRI data elicited by 512-s modern tango, a FFT based band-pass filter was used to further pre-process the fMRI data to remove sources of no interest and noise. Then, a fast model order selection method was applied to estimate the number of sources. Next, both individual ICA and group ICA were performed. Subsequently, ICA components whose temporal courses were significantly correlated …
Transfer of aciclovir from plasma to human breast milk.
2011
Aciclovir (CAS 59277-89-3) is frequently used in herpes simplex virus diseases, but administration to lactating women occurs only rarely. Therefore, information about the pharmacokinetics of aciclovir in human breast milk is limited. The concentration in breast milk is 2 to 3 fold increased compared to plasma. The reason for this increase is unknown until now. An active transport mechanism has been assumed. The aim of this study was to prove whether the higher concentration of aciclovir in human breast milk is due to only a passive transfer. Two chambers separated by a semipermeable membrane were used. The first chamber contained plasma with aciclovir, the second chamber breast milk without…
The impact of isolated lesions on white-matter fiber tracts in multiple sclerosis patients
2015
Infratentorial lesions have been assigned an equivalent weighting to supratentorial plaques in the new McDonald criteria for diagnosing multiple sclerosis. Moreover, their presence has been shown to have prognostic value for disability. However, their spatial distribution and impact on network damage is not well understood. As a preliminary step in this study, we mapped the overall infratentorial lesion pattern in relapsing–remitting multiple sclerosis patients (N = 317) using MRI, finding the pons (lesion density, 14.25/cm3) and peduncles (13.38/cm3) to be predilection sites for infratentorial lesions. Based on these results, 118 fiber bundles from 15 healthy controls and a subgroup of 23 …
Somatotopic organization of the corticospinal tract in the human brainstem: a MRI-based mapping analysis.
2005
To investigate the incompletely understood somatotopical organization of the corticospinal tract in the human brainstem, we performed a voxel-based statistical analysis of standardized magnetic resonance scans of 41 prospectively recruited patients with pyramidal tract dysfunction caused by acute brainstem infarction. Motor hemiparesis was rated clinically and by the investigation of motor evoked potentials to arms and legs. Infarction affected the pons in 85% of cases. We found the greatest level of significance of affected brainstem areas between the pontomesencephalic junction and the mid pons. Lesion location was significantly more dorsal in patients with hemiparesis affecting more prox…
Enhancement of nortriptyline penetration through human epidermis: influence of chemical enhancers and iontophoresis.
2008
Abstract Different known percutaneous chemical enhancers and iontophoresis have been tested in-vitro to study their ability to increase transdermal absorption of nortriptyline hydrochloride (20 mg mL−1). The chemicals 1-dodecanol, Span 20, Azone, (R)-(+)-limonene or isopropyl myristate were used as an overnight pretreatment at 5% (w/w) in ethanol. Furthermore, isopropyl myristate (20%, w/w) and propylene glycol (15%, w/w) were tested in the same vehicle. Iontophoresis was applied directly to the nortriptyline hydrochloride donor solution for three different concentrations (20, 2 and 0.5 mgmL−1). The chemical enhancers slightly increased the nortriptyline transdermal flux but iontophoresis w…
Bio-Preservative Potential of Microorganisms Isolated from Red Grape against Food Contaminant Fungi
2021
Fungal spoilage is one of the main reasons of economic losses in the food industry, especially in the wine sector. Consequently, the search for safer and new preservation techniques has gained importance in recent years. The objective of this study was to investigate the antifungal and anti-mycotoxigenic activity from 28 microorganisms (MO) isolated from red grape. The antifungal activity of a cell free supernatant of fermented medium by the isolated MO (CFS) was tested with the agar diffusion method and the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) assay. Additionally, different antifungal compounds from the CFS were identified and quantified (organi…