Activity

At the binding site Cu-N2O2 coordination prevails, while at the external interface, this coordination partially weakens due to competitive dendrimer-liposome interactions, with only small liposome structural perturbation. Fluorescence anisotropy was used to evaluate the membrane fluidity of both the hydrophobic and hydrophilic parts of the lipid bilayer, while DLS and ZP allowed us to determine the distribution profile of the nanoparticle (PPI glycodendrimer and liposomes) size and surface charge, respectively. From this multitechnique approach, it is deduced that DOTA-PPI glycodendrimers selectively extract Cu(II) ions from the bioenvironment, while these complexes interact with the liposome surface, preferentially with even more negatively charged liposomes. However, these complexes are not able to cross the cell membrane model and poorly perturb the membrane structure, showing their potential for biomedical use.The formation of a stable triacylgermenolate 2 as a decisive intermediate was achieved by using three pathways. The first two methods involve the reaction of KOtBu or alternatively potassium with tetraacylgermane 1 yielding 2 via one electron transfer. The mechanism involves the formation of radical anions (shown by EPR). This reaction is highly efficient and selective. The third method is a classical salt metathesis reaction toward 2 in nearly quantitative yield. The formation of 2 was confirmed by NMR spectroscopy, UV-vis measurements, and X-ray crystallography. Germenolate 2 serves as a starting point for a wide variety of organo-germanium compounds. We demonstrate the potential of this intermediate by introducing new types of Ge-based photoinitiators 4b-4f. The UV-vis absorption spectra of 4b-4f show considerably increased band intensities due to the presence of eight or more chromophores. click here Moreover, compounds 4d-4f show absorption tailing up to 525 nm. The performance of these photoinitiators is demonstrated by spectroscopy (time-resolved EPR, laser flash photolysis (LFP), photobleaching (UV-vis)) and photopolymerization experiments (photo-DSC measurements).To enhance affinity to their hosts, many organisms have evolved to be spiky. This strategy has been inspiring in many fields, but in drug delivery, the feasibility has not yet been extensively explored due to the lack of suitable nanocarriers. Herein, viruslike mesoporous FeSe2 hedgehogs with exceptional photothermal and catalytic performances have been tailored and explored for synergistic tumor therapy. The viruslike topology makes these hedgehogs highly prone to be internalized by cells. By uploading doxorubicin (Dox) into the hollow spikes and encapsulating the hedgehogs with photothermal-meltable gelatin, controlled surface morphology transition from quasi-spherical to spiky and accompanied Dox release have been achieved, with the assistance of the strong photothermal effect of FeSe2 hedgehogs. These integrated features allow specific and controlled drug delivery, leading to synergistic tumor suppression and immunogenic tumor cell death. These results provide new insights into the tailoring of drug carriers relying on their intrinsic physical features.Ten new ent-kaurane diterpenoids, including two pairs of epimers 1/2 and 4/5 and a 6,7-seco-ent-kauranoid 10, were obtained from the aerial parts of Isodon serra. The structures of the new compounds were confirmed by extensive spectroscopic methods and electronic circular dichroism (ECD) data analysis. An anti-inflammatory assay was applied to evaluate their nitric oxide (NO) inhibitory activities by using LPS-stimulated BV-2 cells. Compounds 1 and 9 exhibited notable NO production inhibition with IC50 values of 15.6 and 7.3 μM, respectively. Moreover, the interactions of some bioactive diterpenoids with inducible nitric oxide synthase (iNOS) were explored by employing molecular docking studies.Large critical size bone defects are complicated to treat, and in many cases, autografts become a challenge due to size and availability. In such situations, a synthetic bone implant that can be patient-specifically designed and fabricated with control over parameters such as porosity, rigidity, and osteogenic cues can act as a potential synthetic bone substitute. In this study, we produced photocuring composite resins with poly(trimethylene carbonate) containing high ratios of bioactive ceramics and printed porous 3D composite scaffolds to be used as bone grafts. To enhance the overall surface area available for cell infiltration, the scaffolds were also filled with a macroporous cryogel. Furthermore, the scaffolds were functionalized with osteoactive factors bone morphogenetic protein and zoledronic acid. The scaffolds were evaluated in vitro for biocompatibility and for functionality in vivo in critical bone defects (∼8 mm) in two clinically relevant rabbit models. These studies included a smaller study in rabbit tibia and a larger study in the rabbit cranium. It was observed that the bioactive molecule-functionalized 3D printed porous composite scaffolds provide an excellent conductive surface inducing higher bone formation and improved defect healing in both critical size long bones and cranial defects. Our findings provide strong evidence in favor of these composites as next generation synthetic bone substitutes.The catalytic isomerization of C-C double bonds is an indispensable chemical transformation used to deliver higher-value analogues and has important utility in the chemical industry. Notwithstanding the advances reported in this field, there is compelling demand for a general catalytic solution that enables precise control of the C═C bond migration position, in both cyclic and acyclic systems, to furnish disubstituted and trisubstituted alkenes. Here, we show that catalytic amounts of an appropriate earth-abundant iron-based complex, a base and a boryl compound, promote efficient and controllable alkene transposition. Mechanistic investigations reveal that these processes likely involve in situ formation of an iron-hydride species which promotes olefin isomerization through sequential olefin insertion/β-hydride elimination. Through this strategy, regiodivergent access to different products from one substrate can be facilitated, isomeric olefin mixtures commonly found in petroleum-derived feedstock can be transformed to a single alkene product, and unsaturated moieties embedded within linear and heterocyclic biologically active entities can be obtained.