The synthesis of cyclopropenium-substituted amino compounds and analysis of their photophysical properties is described. Systematic structural modifications of these derivatives lead to measurable and predictable changes in molar extinction coefficients, quantum yields, and Stokes shifts. Using time-dependent density functional theory (TD-DFT) calculations, the origin of these trends was traced to internal charge transfer (ICT) coupled with ensuing structural reorganization for select naphthalene functionalized derivatives. Associated with this structural reorganization was an inward gearing of the cyclopropenium ring and twisting of the peri-NMe group into coplanarity with the naphthalene ring system. Further, reinforcement of an intramolecular H-bond (IMHB) in the excited state of these derivatives alludes to the importance of photoinduced H-bonding in this new class of cyclopropenium based fluorophores.
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http://dx.doi.org/10.1021/acs.joc.8b00770 | DOI Listing |
Acta Biomater
January 2025
Department of Biomedical Engineering, Lund University, Box 118, 221 00 Lund, Sweden.
While the number of studies investigating Achilles tendon pathologies has grown exponentially, more research is needed to gain a better understanding of the complex relation between its hierarchical structure, mechanical response, and failure. At the microscale, collagen fibers are, with some degree of dispersion, primarily aligned along the principal loading direction. However, during tension, rearrangements and reorientations of these fibers are believed to occur.
View Article and Find Full Text PDFAnn Phys Rehabil Med
January 2025
Department of Rehabilitation Medicine, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo, 181-8611, Japan; Department of Rehabilitation Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan. Electronic address:
Background: Despite the lack of clinically validated strategies for treating spinal cord injury (SCI), combining therapeutic strategies with rehabilitation is believed to promote recovery of motor function; however, current research findings are inconsistent.
Objectives: To explore whether combination therapy involving therapy and rehabilitative training (CIRT) has a synergistic effect on motor function recovery in animal models of SCI.
Methods: We conducted a systematic review and meta-analysis of studies identified in a keyword search of 6 databases and extracted open-field motor scores from the Basso Mouse Scale (BMS) and the Basso, Beattie, and Bresnahan Locomotor Rating Scale (BBB) for meta-analysis using a weighted mean difference (WMD) and 95 % CI.
Sleep
January 2025
UR2NF-Neuropsychology and Functional Neuroimaging Research Unit affiliated at CRCN - Centre for Research in Cognition and Neurosciences and UNI - ULB Neuroscience Institute, Université Libre de Bruxelles (ULB), Brussels, Belgium.
Enhancing the retention of recent memory traces through sleep reactivation is possible via Targeted Memory Reactivation (TMR), involving cueing learned material during post-training sleep. Evidence indicates detectable short-term microstructural changes in the brain within an hour after motor sequence learning, and post-training sleep is believed to contribute to the consolidation of these motor memories, potentially leading to enduring microstructural changes. In this study, we explored how TMR during post-training sleep affects performance gains and delayed microstructural remodeling, using both standard Diffusion Tensor Imaging (DTI) and advanced Neurite Orientation Dispersion & Density Imaging (NODDI).
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China. Electronic address:
This study investigated the dynamic changes in legume starches (common vetch, mung bean, and pea) during gelatinization. All three starches displayed a similar pattern: water absorption and swelling at lower temperatures (50-65 °C), structural rupture at medium temperatures (65-75 °C), and melting/reorganization at higher temperatures (75-90 °C). Gelatinization likely starts with internal structural dissociation, as evidenced by the weakening of the double helix structure and decreasing order observed throughout the process.
View Article and Find Full Text PDFJ Pharm Biomed Anal
January 2025
Department of Pharmaceutical Analysis, School of Pharmacy, Guizhou Medical University, Gui'an New District, Guizhou 561113, PR China. Electronic address:
Dendrobine is a sesquiterpene alkaloid primarily used in the treatment of inflammatory diseases, immune system disorders, and conditions related to oxidative stress. To understand the possible degradation pathways of dendrobine for its quality control, we conducted an in-depth investigation of its degradation products using forced degradation methods. The separation of dendrobine and its degradation products was achieved on a Shim-pack XR-ODS III (75 mm × 2 mm, 1.
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