Purpose: In this study, the basic properties and requirements of time-encoded pseudocontinuous arterial spin labeling (te-pCASL) are investigated. Also, the extra degree of freedom delivered by changing block durations is explored.
Methods: First, the minimal duration of encoding blocks, the influence of cardiac triggering, and the effect of dividing the labeling period into blocks are evaluated. Two new strategies for timing the encoding blocks in te-pCASL are introduced: variable block duration to compensate for T1-decay and the free lunch approach that uses the postlabeling delay time that is idle in standard pCASL to acquire arterial transit time (ATT) information. Simulations are used to probe possible signal losses.
Results: No signal loss was found when dividing the labeling period into blocks with duration >50 ms. In time-encoded perfusion imaging, no cardiac triggering is required. Summation of results for individual blocks in te-pCASL postprocessing causes severe loss of temporal SNR. Quality of cerebral blood flow (CBF) maps was not affected by the encoding line order.
Conclusion: Adjusting the timing of encoding blocks in te-pCASL allows for tailoring the acquisition to specific applications. With the free lunch setup, te-pCASL delivers CBF and high resolution ATT maps within a single scan, with a small penalty in tSNR.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/mrm.25083 | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125.
Cognition relies on transforming sensory inputs into a generalizable understanding of the world. Mirror neurons have been proposed to underlie this process, mapping visual representations of others' actions and sensations onto neurons that mediate our own, providing a conduit for understanding. However, this theory has limitations.
View Article and Find Full Text PDFInt J Oncol
February 2025
Department of Pathology, GROW Research Institute for Oncology and Reproduction, Maastricht University Medical Center, 6229HX Maastricht, The Netherlands.
Human papillomavirus (HPV)‑positive and -negative head and neck squamous cell carcinoma (HNSCC) are often associated with activation of the phosphatidylinositol 3‑kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway due to mutations or amplifications in , loss of or activation of receptor tyrosine kinases. In HPV‑negative tumors, (encoding p16 protein) inactivation or (encoding Cyclin D1 protein) amplification frequently results in sustained cyclin‑dependent kinase (CDK) 4/6 activation. The present study aimed to investigate the efficacy of the CDK4/6 inhibitors (CDKi) palbociclib and ribociclib, and the PI3K/Akt/mTOR pathway inhibitors (PI3Ki) gedatolisib, buparlisib and alpelisib, in suppressing cell viability of HPV‑positive and ‑negative HNSCC cell lines.
View Article and Find Full Text PDFBMC Genomics
January 2025
Unit of Mycoplasmas, Laboratory of Molecular Microbiology, Vaccinology and Biotechnology Development, Institut Pasteur de Tunis, University Tunis El Manar, Tunis, Tunisia.
Background: Avian mycoplasmas are small bacteria associated with several pathogenic conditions in many wild and poultry bird species. Extensive genomic data are available for many avian mycoplasmas, yet no comparative studies focusing on this group of mycoplasmas have been undertaken so far.
Results: Here, based on the comparison of forty avian mycoplasma genomes belonging to ten different species, we provide insightful information on the phylogeny, pan/core genome, energetic metabolism, and virulence of these avian pathogens.
Sci Rep
January 2025
Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden.
Antimicrobial resistance (AMR) is an increasing problem worldwide, and new treatment options for bacterial infections are direly needed. Engineered probiotics show strong potential in treating or preventing bacterial infections. However, one concern with the use of live bacteria is the risk of the bacteria acquiring genes encoding for AMR or virulence factors through horizontal gene transfer (HGT), and the transformation of the probiotic into a superbug.
View Article and Find Full Text PDFVaccine
January 2025
Department of Global Health, George Washington University, Washington, D.C., USA. Electronic address:
Transmission-blocking vaccines (TBVs) targeting sexual-stage antigens represent a critical tool for malaria control and elimination through inhibiting parasite development within mosquitoes. P230, displayed on the surface of gametocytes and gametes, plays a crucial role in gamete fertilization and is one of the leading TBV candidates for both Plasmodium falciparum and P. vivax.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!