In the present study we investigated the effects of water exchange between intra- and extravascular compartments on absolute quantification of regional myocardial blood flow (rMBF) using a saturation-recovery sequence with a rather long inversion time (TI, 176 ms) and a T1-shortening intravascular contrast agent (CMD-A2-Gd-DOTA). Data were acquired in normal and ischemically injured pigs, with radiolabeled microsphere flow measurements used as the gold standard. Five water exchange rates (fast, 6 Hz, 3 Hz, 1 Hz, and no exchange) were tested. The results demonstrate that the fast-exchange approximation may be appropriate for rMBF quantification using the described experimental setting. Relaxation rate change (DeltaR1) analysis improved the accuracy of the analysis of rMBF compared to the MR signal. In conclusion, the current protocol could provide sufficient accuracy for estimating rMBF assuming fast exchange and a linear relationship between signal and tissue concentration when quantification of precontrast T1 is not an option.
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Front Physiol
January 2025
Departamento de Anatomía, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
Introduction: Access to electric light has exposed living organisms to varying intensities of light throughout the 24 h day. Dim light at night (DLAN) is an inappropriate signal for the biological clock, which is responsible for the circadian organization of physiology. During the gestational period, physiological adaptations occur to ensure a successful pregnancy and optimal fetal development.
View Article and Find Full Text PDFAnal Chem
January 2025
State Key Laboratory of Surface Physics and Department of Physics, Academy for Engineering and Technology, Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), Shanghai Key Laboratory of Metasurfaces for Light Manipulation, Fudan University, Shanghai 200433, China.
Numerous chemical reactions and most life processes occur in aqueous solutions, where the physical diffusion of small molecules plays a vital role, including solvent water molecules, solute biomolecules, and ions. Conventional methods of measuring diffusion coefficients are often limited by technical complexity, large sample consumption, or significant time cost. Here, we present an optical imaging method to study molecular diffusion by combining stimulated Raman scattering (SRS) microscopy with microfluidics: a "Y"-shaped microfluidic channel forming two laminar flows with a stable concentration gradient across the interface.
View Article and Find Full Text PDFBMC Bioinformatics
January 2025
Institute for Human Genetics, University Medical Center Johannes Gutenberg University, 55131, Mainz, Germany.
Background: Tissue clearing combined with light-sheet microscopy is gaining popularity among neuroscientists interested in unbiased assessment of their samples in 3D volume. However, the analysis of such data remains a challenge. ClearMap and CellFinder are tools for analyzing neuronal activity maps in an intact volume of cleared mouse brains.
View Article and Find Full Text PDFMycoses
January 2025
Laboratorio de Micología y Diagnóstico Molecular-Cátedra de Parasitología y Micología-Bioquímica, Universidad Nacional del Litoral, Santa Fe, Argentina.
Background: Access to fungal disease diagnosis is crucial for reducing mortality, yet it varies widely across Argentina, especially outside Buenos Aires. In regions like Santa Fe and Paraná, where most healthcare facilities are under 150 beds, maintaining specialised mycology labs is challenging.
Objectives: This work describes the establishment and first-year results of a centralised Fungal Disease Response Centre (FDRC) and referral network serving this region, covering approximately 1 million inhabitants.
Sci Rep
January 2025
Department of Rehabilitation, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China.
Extubation failure rates are notably high in patients in neurointensive care. Ineffective cough is the variable independently associated with extubation failure, but its quantification remains challenging. Patients with primary central nervous system injury requiring invasive mechanical ventilation were included.
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