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Acellular Dermal Matrix (ADM) provides mechanical and soft tissue support in implant-based breast reconstruction, and has shown to modulate the healing response. However, skin flap necrosis, edema, and previous radiation therapy can hinder ADM integration. Effective biomaterial integration requires regulating the immune response, fibrosis, and adipocyte-driven functionalization. Extracellular matrix (ECM) hydrogels have demonstrated utility in tissue regeneration, and decreasing inflammation and fibrosis in various tissues. Therefore, we hypothesized that a Decellularized Porcine Dermal (DPD) hydrogel to support ADM integration would prevent excessive fibrosis, regulate the macrophage response, and promote adipogenesis. Exploration of DPD hydrogel during ADM implantation in mice (healthy and radiated) revealed long-term effects of irradiation on implant wound healing. DPD hydrogel rescued radiation-induced fibrosis, restoring capsule thickness of healthy mice, and did not increase the fibroblast migration into the ADM. As a modulating soft tissue filler, DPD hydrogel also promoted adipocyte infiltration in healthy and irradiated mice. Detailed macrophage analysis showed that radiation led to the increase in pro-inflammatory, transition, and reparative markers. Despite relatively subtle effects on individual macrophage phenotype markers, multidimensional flow cytometry analysis revealed that DPD hydrogel temporally regulated two subpopulations. he presence of DPD resulted in significantly reduced CD9HiArg1HiCD301bLo and CD163HiCD38HiCD301bHi macrophages in healthy mice at one week, and a significant increase in CD9High macrophages with low expression of other markers at 6 weeks in irradiated mice. DPD hydrogel promotes a decreased fibrotic, and adipocyte-promoting coordination of wound healing in healthy and irradiated wound beds while not disrupting the immunomodulatory effects of ADM. Acellular Dermal Matrix (ADM) provides mechanical and soft tissue support in post-mastectomy implant-based breast reconstruction, and positively affects wound healing. Following breast reconstruction, skin flap necrosis, edema, and previous radiation therapy can hinder ADM integration. Effective wound healing and biomaterial integration requires regulating the cellular immune response. Extracellular matrix hydrogels have demonstrated utility in tissue regeneration and decreasing inflammation and fibrosis in various tissues, but has yet to be utilized in the setting of breast reconstruction. Here, we demonstrated that a decellularized dermal hydrogel as an adjunct to ADM, decreases fibrosis and promotes adipogenesis during the coordination of wound healing in healthy and clinically relevant microenvironments that have received radiation therapy while not disrupting the immunomodulatory effects of implanted ADM. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: In this work, a novel photoelectrochemical fuel cell consisting of a titanium dioxide nanotube array photosensitive anode and a platinum cathode was made for decomposing environmentally hazardous materials to produce electricity and clean fuel. Titanium dioxide nanotubes (TiO2 NTs) were prepared via electrochemical oxidation of pure Ti in an ammonium fluoride and glycerol-containing solution. Scanning electron microscopy was used to analyze the morphology of the nanotubes. The average diameter, wall thickness and length of the as-prepared TiO2 NTs were determined. The photosensitive anode made from the highly ordered TiO2 NTs has good photo-catalytic property, as proven by the decomposition tests on urea, ammonia, sodium sulfide and automobile engine coolant under ultraviolet (UV) radiation. To improve the efficiency of the fuel cell, doping the TiO2 NTs with a transition metal oxide, NiO, was performed and the photosensitivity of the doped anode was tested under visible light irradiation. It is found that the NiO-doped anode is sensitive to visible light. Also found is that polyaniline-doped photosensitive anode can harvest photon energy in the visible light spectrum range much more efficiently than the NiO-doped one. It is concluded that the nanostructured photoelectrochemical fuel cell can generate electricity and clean fuel by decomposing hazardous materials under sunlight. [Copyright &y& Elsevier]

Abstract Pyrroles and quinolones represent core structures, which are routinely found in both natural and synthetic bioactive substances. Consequently, the development of efficient and regiospecific methods for the preparation of such heterocycles with unique functionality is of some importance. We describe herein the regiospecific synthesis of 1,2,3,4-tetrasubstituted pyrroles containing polar substituents and such products are prepared from vinylogous carbamates and vinylogous aminonitriles. We also describe the regiospecific synthesis of 3-aryl containing 1,3,6-trisubstituted quinolones from vinylogous carbamates. The use of an amine exchange reaction to prepare precursors for the pyrrole and quinolone forming cyclizations represents a key factor in the strategy. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Highly functionalized pyrroles with appropriate regiochemical functionality represent an important class of marine natural products and potential drug candidates. We describe herein a detailed study of the reaction of α-aminoacid esters with vinylogous amides and also β-halovinylaldehydes for the regiospecific synthesis of 2,3,4-trisubstituted and 1,2,3,4-tetrasubstituted pyrroles. Since the vinylogous amides and β-halovinylaldehydes are readily available precursors, rapid access to a wide variety of unsymmetrically substituted pyrroles is accomplished via this methodology. [ABSTRACT FROM AUTHOR]

α-Conotoxins inhibit nicotinic acetylcholine receptors (nAChRs) and are used as probes to study cholinergic pathways in vertebrates. Model organisms, such as Drosophila melanogaster, express nAChRs in their CNS that are suitable to investigate the neuropharmacology of α-conotoxins in vivo . Here we report the paired nanoinjection of native α-conotoxin PIA and two novel α-conotoxins, PIC and PIC[O7], from the injected venom of Conus purpurascens and electrophysiological recordings of their effects on the giant fiber system (GFS) of D. melanogaster and heterologously expressed nAChRs in Xenopus oocytes. α-PIA caused disruption of the function of giant fiber dorsal longitudinal muscle (GF-DLM) pathway by inhibiting the Dα7 nAChR a homolog to the vertebrate α7 nAChR, whereas PIC and PIC[O7] did not. PIC and PIC[O7] reversibly inhibited ACh-evoked currents mediated by vertebrate rodent (r)α1β1δγ, rα1β1δε and human (h)α3β2, but not hα7 nAChR subtypes expressed in Xenopus oocytes with the following selectivity: rα1β1δε > rα1β1δγ ≈ hα3β2 >> hα7. Our study emphasizes the importance of loop size and α-conotoxin sequence specificity for receptor binding. These studies can be used for the evaluation of the neuropharmacology of novel α-conotoxins that can be utilized as molecular probes for diseases such as, Alzheimer's, Parkinson's, and cancer. This article is part of the Special Issue entitled ‘Venom-derived Peptides as Pharmacological Tools.’ [ABSTRACT FROM AUTHOR]