Localized phosphorus-31 MR spectra were obtained in vivo in a large series of normal human brain tissue specimens of healthy volunteers (n=36) and various brain tumours (n=52). Tumour types examined included grade II and grade III gliomas (n=15 and n=1, respectively), glioblastomas (n=16) and meningeomas (n=12). An additional eight tumours were analysed during chemo- or radiotherapy. Spectra were acquired using a modified ISIS pulse sequence with a repetition time of 3 s. Voxel sizes ranged from 56 to 129 ml. The spectra were evaluated using a least-square variable projection (VARPRO) fitting procedure in the time domain, which allows semi-quantitative determination of relative metabolite concentrations. The measurements in normal cerebrum of healthy volunteers revealed the following results of metabolite signal intensity ratios: pH 7.04 (+/- 0.01), PCr/alpha-ATP 0.51 (+/- 0.03), P(i)/alpha-ATP 0.17 (+/-0.02), PCr/P(i) 2.09 (+/-0.12), PDE/alpha-ATP 3.65 (+/-0.13) and PME/alpha-ATP 0.41 (+/-0.04). Meningiomas showed the most obvious changes when compared with normal brain tissue. They are characterized by an alkaline environment (pH 7.16 +/- 0.03; p<0.005), a decrease in the phosphocreatine peak (p<0.0001) and significantly decreased phosphodiesters (p<0.0001). Glioblastomas also showed alkalization (pH 7.12 +/- 0.02; p<0.001) and a decrease in PDE/alpha-NTP (p<0.05), but no significant changes in PCr/alpha-NTP or PCr/Pi. In gliomas with low malignancy, less distinct changes could be detected with slight alkalization (pH 7.09 +/- 0.02; p<0.05) and more than a two-fold reduction in the PDE/alpha-NTP ratio (p<0.05). The spectra of brain tumours during chemo- and radiotherapy indicated clear but inconsistent influence of the therapy.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/nbm.735 | DOI Listing |
Viruses
December 2024
Department of Medical Oncology, Medical University of Sofia, University Hospital "Tsaritsa Yoanna", 1527 Sofia, Bulgaria.
Central nervous system (CNS) infections caused by SARS-CoV-2 are uncommon. This case report describes the clinical progression of a 92-year-old female who developed a persistent neuroinfection associated with SARS-CoV-2. The patient initially presented with progressive fatigue, catarrhal symptoms, and a fever (38.
View Article and Find Full Text PDFViruses
November 2024
Department of Biological Sciences, University of Alabama, Tuscaloosa, AL 35487, USA.
Unlabelled: Di(2-ethhylhexyl) phthalate (DEHP) is a common plastic rubberizer. DEHP leaches from plastic matrices and is under increasing scrutiny as numerous studies have linked it to negative human health manifestations. Coxsackievirus B3 (CVB) is a human pathogen that typically causes subclinical infections but can sometimes cause severe diseases such as pancreatitis, myocarditis, and meningoencephalitis.
View Article and Find Full Text PDF: West Nile virus (WNV) is a rapidly growing problem worldwide. The lack of emergency treatment and a safe licensed vaccine against WNV allows the virus to cause sporadic outbreaks of human disease, including fatal cases. Formalin-inactivated vaccines have been used for a long time and have been shown to be very safe and effective, especially in susceptible populations.
View Article and Find Full Text PDFSensors (Basel)
December 2024
School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
Freezing of gait (FOG) is a walking disturbance that can lead to postural instability, falling, and decreased mobility in people with Parkinson's disease. This research used machine learning to predict and detect FOG episodes from plantar-pressure data and compared the performance of decision tree ensemble classifiers when trained on three different datasets. Dataset 1 ( = 11) was collected in a previous study.
View Article and Find Full Text PDFSensors (Basel)
December 2024
Division of Neurological Rehabilitiation, Instituto Nacional de Rehabilitacion Luis Guillermo Ibarra Ibarra, Mexico City 14389, Mexico.
Stroke is a global health issue caused by reduced blood flow to the brain, which leads to severe motor disabilities. Measuring oxygen levels in the brain tissue is crucial for understanding the severity and evolution of stroke. While CT or fMRI scans are preferred for confirming a stroke due to their high sensitivity, Near-Infrared Spectroscopy (NIRS)-based systems could be an alternative for monitoring stroke evolution.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!