Colloidal Polymeric Platform for Facile Click-Assisted Ligand Functionalization and Receptor Targeting

Colloidal poly­(glycidyl methacrylate) nanoparticles (NPs) are demonstrated to be platforms facilitating the “click” chemistry approach of surface functionalization for receptor targeting. Folate receptor-targeted NPs were synthesized, physicochemically characterized, confirmed for their biocompatibility, and validated for their selective targeting capabilities for ovarian cancer cells in vitro

Examining Efficacy of “TAT-less” Delivery of a Peptide against the L‑Type Calcium Channel in Cardiac Ischemia–Reperfusion Injury

Increased calcium influx through the L-type Ca²⁺ channel or overexpression of the alpha subunit of the channel induces cardiac hypertrophy. Cardiac hypertrophy results from increased oxidative stress and alterations in cell calcium levels following ischemia–reperfusion injury and is an independent risk factor for increased morbidity and mortality. We find that decreasing the movement of the auxiliary beta subunit with a peptide derived against the alpha-interacting domain (AID) of the channel attenuates ischemia–reperfusion injury. We compared the efficacy of delivering the AID peptide using a trans-activator of transcription (TAT) sequence with that of the peptide complexed to multifunctional polymeric nanoparticles. The AID-tethered nanoparticles perfused through the myocardium more diffusely and associated with cardiac myocytes more rapidly than the TAT-labeled peptide but had similar effects on intracellular calcium levels. The AID-complexed nanoparticles resulted in a similar reduction in release of creatine kinase and lactate dehydrogenase after ischemia–reperfusion to the TAT-labeled peptide. Since nanoparticle delivery also holds the potential for dual drug delivery, we conclude that AID-complexed nanoparticles may provide an effective platform for peptide delivery in cardiac ischemia–reperfusion injuries

Fibroblasts on RADA16-Fibronectin (1% wt)

Live cell tracking migration assay with fibroblasts on RADA16-Fibronectin (1% wt)

Keratinocytes on RADA16-Collagen I (1% wt)

Live cell tracking migration assay with keratinocytes on RADA16-Collagen I (1% wt)

Keratinocytes on RADA16 (1% wt)

Live cell tracking migration assay with keratinocytes on RADA16 (1% wt)

Keratinocytes on RADA16-Fibronectin (1% wt)

Live cell tracking migration assay with keratinocytes on RADA16-Fibronectin (1% wt)

Fibroblasts on RADA16-Collagen I (1% wt)

Live cell tracking migration assay with fibroblasts on RADA16-Collagen I (1% wt)

Iron Oxide-Induced Thermal Effects on Solid-State Upconversion Emissions in NaYF₄:Yb,Er Nanocrystals

Multifunctional materials exhibiting photon upconversion show promising applications for biological imaging and sensing. In this study, we examine the solid-state upconversion emission of NaYF₄:Yb,Er nanoparticles in the presence of iron oxide nanoparticles. Fe₃O₄ nanoparticles (6 nm) were mixed with NaYF₄:Yb,Er nanoparticles (either 10 or 50 nm) in varying proportions by drying chloroform solutions of nanoparticles onto glass slides. Upconversion spectra were acquired, and a laser power-dependent emission was observed and correlated with the iron oxide content in the mixture. Changes in the lattice temperature of the upconverting particles were monitored by careful observation of the relative intensities of the ²H_11/2 and ⁴S_3/2 →⁴I_15/2 transitions. The emission characteristics observed are consistent with an iron oxide-induced thermal effect that is dependent on both the laser power and the proportion of iron oxide. The results highlight that the thermal effects of mixed nanoparticle systems should be considered in the design of luminescent upconverting hybrid materials

Une cloche sonnant la retraite nommée "Côparèye". Petit essai de campanonymie et de sémiologie campanaire

L'article propose l'étymologie du nom de la cloche la plus fameuse de la cathédrale Saint-Lambert de Liège et jette les bases d'une campanonymie (étude des noms de cloches) d'origine délocutive (mots tirant leur origine d'énoncés).Peer reviewe

Nanoparticle-Mediated Dual Delivery of an Antioxidant and a Peptide against the L‑Type Ca²⁺ Channel Enables Simultaneous Reduction of Cardiac Ischemia-Reperfusion Injury

Increased reactive oxygen species (ROS) production and elevated intracellular Ca²⁺ following cardiac ischemia-reperfusion injury are key mediators of cell death and the development of cardiac hypertrophy. The L-type Ca²⁺ channel is the main route for calcium influx in cardiac myocytes. Activation of the L-type Ca²⁺ channel leads to a further increase in mitochondrial ROS production and metabolism. We have previously shown that the application of a peptide derived against the alpha-interacting domain of the L-type Ca²⁺ channel (AID) decreases myocardial injury post reperfusion. Herein, we examine the efficacy of simultaneous delivery of the AID peptide in combination with the potent antioxidants curcumin or resveratrol using multifunctional poly(glycidyl methacrylate) (PGMA) nanoparticles. We highlight that drug loading and dissolution are important parameters that have to be taken into account when designing novel combinatorial therapies following cardiac ischemia-reperfusion injury. In the case of resveratrol low loading capacity and fast release rates hinder its applicability as an effective candidate for simultaneous therapy. However, in the case of curcumin, high loading capacity and sustained release rates enable its effective simultaneous delivery in combination with the AID peptide. Simultaneous delivery of the AID peptide with curcumin allowed for effective attenuation of the L-type Ca²⁺ channel-activated increases in superoxide (assessed as changes in DHE fluorescence; Empty NP = 53.1 ± 7.6%; NP-C-AID = 7.32 ± 3.57%) and mitochondrial membrane potential (assessed as changes in JC-1 fluoresence; Empty NP = 19.8 ± 2.8%; NP-C-AID=13.05 ± 1.78%). We demonstrate in isolated rat hearts exposed to ischemia followed by reperfusion, that curcumin and the AID peptide in combination effectively reduce muscle damage, decrease oxidative stress and superoxide production in cardiac myocytes