Introduction: Ischemic stroke is a potential complication of hypereosinophilic syndromes (HES), and little is known about underlying pathophysiological mechanisms. We aimed to describe the imaging patterns of cerebral ischemia in patients with HES.
Methods: An individual case is reported.
Introduction: Since the onset of the coronavirus disease 2019 (COVID-19) pandemic, wearing surgical face masks has become mandatory for healthcare staff in many countries when interacting with patients. Recently, it has been shown that wearing face masks impairs social interaction by diminishing a person's ability to read the emotion of their counterparts, an essential prerequisite to respond adequately in social situations. It is easily conceivable that this may have a tangible negative influence on the communication and relationship between patients and healthcare personnel.
View Article and Find Full Text PDFA large body of molecular and neurophysiological evidence connects synaptic plasticity to specific functions and energy metabolism in particular areas of the brain. Furthermore, altered plasticity and energy regulation has been associated with a number of neuropsychiatric disorders. A favourable approach enabling the modulation of neuronal excitability and energy in humans is to stimulate the brain using transcranial direct current stimulation (tDCS) and then to observe the effect on neurometabolites using magnetic resonance spectroscopy (MRS).
View Article and Find Full Text PDFAlterations in the substantia nigra are strongly associated with Parkinson's disease. However, due to low contrast and partial volume effects present in typical MRI images, the substantia nigra is not of sufficient size to obtain a reliable segmentation for region-of-interest based analysis. To combat this problem, the approach proposed here offers a method to investigate and reveal changes in quantitative MRI parameters in the vicinity of substantia nigra without any a priori delineation.
View Article and Find Full Text PDFInterest in white matter hyperintensities (WMH), a radiological biomarker of small vessel disease, is continuously increasing. This is, in most part, due to our better understanding of their association with various clinical disorders, such as stroke and Alzheimer's disease, and the overlapping pathology of WMH with these afflictions. Although post-mortem histological studies have reported various underlying pathophysiological substrates, in vivo research has not been specific enough to fully corroborate these findings.
View Article and Find Full Text PDFBackground: Body mass index (BMI) is increasing in a large number of elderly persons. This increase in BMI is known to put one at risk for many "diseases of aging," although less is known about how a change in BMI may affect the brains of the elderly.
Purpose: To investigate the relationship between BMI and quantitative water content, T , T *, and the semi-quantitative magnetization transfer ratio (MTR) of various structures in elderly brains.
A new parameter estimation algorithm, MERLIN, is presented for accurate and robust multi-exponential relaxometry using magnetic resonance imaging, a tool that can provide valuable insight into the tissue microstructure of the brain. Multi-exponential relaxometry is used to analyze the myelin water fraction and can help to detect related diseases. However, the underlying problem is ill-conditioned, and as such, is extremely sensitive to noise and measurement imperfections, which can lead to less precise and more biased parameter estimates.
View Article and Find Full Text PDFQuantitative imaging of the human brain is of great interest in clinical research as it enables the identification of a range of MR biomarkers useful in diagnosis, treatment and prognosis of a wide spectrum of diseases. Here, a 3D two-point method for water content and relaxation time mapping is presented and compared to established gold standard methods. The method determines free water content, H2O, and the longitudinal relaxation time, T1, quantitatively from a two-point fit to the signal equation including corrections of the transmit and receive fields.
View Article and Find Full Text PDFKosm Biol Aviakosm Med
July 1976
The paper presents the results of an exposure of cells of the Syrian hamster strain VNK-21 to space flight effects. In contrast to the cell culture kept in a thermostat at 29 degrees C, the cell culture that was maintained in thermally uncontrolled conditions developed noticeable structural and physiological changes induced by suboptimal temperatures. It was concluded that a 6-day exposure to weightlessness exerted no adverse effect on mammalian cells in vitro and produced no stable structural or physiological changes.
View Article and Find Full Text PDFDrosophila melanogaster flies of strain D-32 were exposed aboard the Soyuz 10 spaceship. An insert with a nutritional medium and insects was placed in a small on-board thermostat (Biotherm II) providing a constant temperature (24 degrees C +/- 1 degree) for Drosophila development. The frequency of dominant lethals was determined in the females.
View Article and Find Full Text PDF