A polymer-grafted liposomal formulation that has the potential to be developed for aerosolic pulmonary delivery of vasoactive intestinal peptide (VIP), a potent vasodilatory neuropeptide, is described. As VIP is prone to rapid proteolytic degradation in the microenvironment of the lung a proper delivery system is required to increase the half-life and bioavailability of the peptide. Here we investigate structural parameters of unilamellar liposomes composed of palmitoyl-oleoyl-phosphatidylcholine, lyso-stearyl-phosphatidylglycerol and distearyl-phosphatidyl-ethanolamine covalently linked to polyethylene glycol 2000, and report on VIP-lipid interaction mechanisms. We found that the cationic VIP is efficiently entrapped by the negatively charged spherical liposomes and becomes converted to an amphipathic alpha-helix. By fluorescence spectroscopy using single Trp-modified VIP we could show that VIP is closely associated to the membrane. Our data suggest that the N-terminal random-coiled domain is embedded in the interfacial headgroup region of the phospholipid bilayer. By doing so, neither the bilayer thickness of the lipid membrane nor the mobility of the phospholipid acyl chains are affected as shown by small angle X-ray scattering and electron spin resonance spectroscopy. Finally, in an ex vivo lung arterial model system we found that liposomal-associated VIP is recognized by its receptors to induce vasodilatory effects with comparable high relaxation efficiency as free VIP but with a significantly retarded dilatation kinetics. In conclusion, we have designed and characterized a liposomal formulation that is qualified to entrap biologically active VIP and displays structural features to be considered for delivery of VIP to the lung.
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http://dx.doi.org/10.1016/j.bbamem.2006.11.017 | DOI Listing |
Eur J Nucl Med Mol Imaging
January 2025
Departments of Radiology and Medical Physics, University of Wisconsin - Madison, Madison, WI, 53705, USA.
Purpose: Trophoblast cell-surface antigen 2 (Trop2) is overexpressed in various solid tumors and contributes to tumor progression, while its expression remains low in normal tissues. Trop2-targeting antibody-drug conjugate (ADC), sacituzumab govitecan-hziy (Trodelvy), has shown efficacy in targeting this antigen. Leveraging the enhanced specificity of ADCs, we conducted the first immunoPET imaging study of Trop2 expression in gastric cancer (GC) and triple-negative breast cancer (TNBC) models using Zr-labeled Trodelvy ([Zr]Zr-DFO-Trodelvy).
View Article and Find Full Text PDFFront Nutr
January 2025
Department of Epidemiology and Health Statistics, Tianjin Medical University, Tianjin, China.
Background: Although more risk prediction models are available for feeding intolerance in enteral-nourishment patients, it is still unclear how well these models will work in clinical settings. Future research faces challenges in validating model accuracy across populations, enhancing interpretability for clinical use, and overcoming dataset limitations.
Objective: To thoroughly examine studies that have been published on feeding intolerance risk prediction models for enteral nutrition patients.
BMC Med Inform Decis Mak
January 2025
Department of Critical Care Medicine, First Affiliated Hospital of Harbin Medical University, Heilongjiang, China.
Background: Acute respiratory distress syndrome (ARDS) is a serious threat to human life. Hence, early and accurate diagnosis and treatment are crucial for patient survival. This meta-analysis evaluates the accuracy of artificial intelligence in the early diagnosis of ARDS and provides guidance for future research and applications.
View Article and Find Full Text PDFNat Immunol
January 2025
State Key Laboratory of Respiratory Disease, National Clinical Research Centre for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
Mucosal antigen-specific T cells are pivotal for pathogen clearance and immune modulation in respiratory infections. Dysregulated T cell responses exacerbate coronavirus disease 2019 severity, marked by cytokine storms and respiratory failure. Despite extensive description in peripheral blood, the characteristics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T cells in the lungs remain elusive.
View Article and Find Full Text PDFEcotoxicol Environ Saf
January 2025
Department of Epidemiology and Health Statistics, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Clinical Research Unit, The Second Affiliated Hospital, Fujian Medical University, Quanzhou 362000, China. Electronic address:
Environmental pollutants have been implicated in various detrimental health effects. However, the specific relationship between environmental pollutant exposure and the risk of cerebrovascular disease mortality remains uncertain. This study aimed to comprehensively explore the potential relationship between environmental pollutant exposure and risk of cerebrovascular disease mortality in the U.
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