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Fabrication of vascularized large-scale constructs for regenerative medicine remains elusive since most strategies rely solely on cell self-organization or overly control cell positioning, failing to address nutrient diffusion limitations. We propose a modular and hierarchical tissue-engineering strategy to produce bonelike tissues carrying signals to promote prevascularization. In these 3D systems, disc-shaped microcarriers featuring nanogrooved topographical cues guide cell behavior by harnessing mechanotransduction mechanisms. A sequential seeding strategy of adipose-derived stromal cells and endothelial cells is implemented within compartmentalized, liquefied-core macrocapsules in a self-organizing and dynamic system. Importantly, our system autonomously promotes osteogenesis and construct's mineralization while promoting a favorable environment for prevascular-like endothelial organization. Given its modular and self-organizing nature, our strategy may be applied for the fabrication of larger constructs with a highly controlled starting point to be used for local regeneration upon implantation or as drug-screening platforms. published

[Image: see text] In this study, we show that fluorescent boronic-acid derived salicylidenehydrazone complexes (BASHY) can function as fluorescent linkers for bioconjugates that were used to monitor the delivery of the proteasome inhibitor bortezomib (Btz) to HT-29 cancer cells. BASHY complexes were structurally optimized to improve the stability of the complex in buffered conditions (ammonium acetate, pH 7 up to t(1/2) = 40 h), photophysically characterized regarding their fluorescence properties and used in confocal microscopy colocalization studies that revealed their intracellular sequestration by lipid droplets. The accumulation in these hydrophobic organelles limited the hydrolysis of the complex and consequently the drug release, a problem that was circumvented by the conjugation of the BASHY-Btz complex with a cell-penetrating peptide GV1001-C. The conjugate exhibited an improved cytoplasmic availability as confirmed by confocal fluorescence microscopy studies and an improved potency against HT-29 cancer cells (IC(50) = 100 nM) as compared to the nontargeted complex (IC(50) = 450 nM).

Complexes [Ag(H2BzPh)NO3] (1), [Ag(H2BzpCH3Ph)NO3] (2), [Ag(H2BzpClPh)NO3] (3), and [Ag(H2BzpNO2Ph)NO3] (4) were synthesized with 2-benzoylpyridine benzoylhydrazone (H2BzPh) and its para-methyl-benzoylhydrazone (H2BzpCH3Ph), para-chloro-benzoylhydrazone (H2BzpClPh), and para-nitro-benzoylhydrazone (H2BzpNO2Ph) derivatives. Experimental data indicate that the nitrate ligand binds more strongly to the silver center through one of the oxygen atoms, whereas the second oxygen atom from nitrate and the hydrazone oxygen makes much weaker interactions with the metal. Dissociation of nitrate most probably occurs in solution and in biological media. Interestingly, theoretical calculations suggested that when dissociation of the nitrate takes place, all bond orders involving the metal and the atoms from the hydrazone ligand increase significantly, showing that the bonding of nitrate results in the weakening of all other interactions in the metal coordination sphere. Upon complexation of the hydrazones to silver(I), cytotoxicity against B16F10 metastatic murine melanoma cells increased in all cases. Complexes (1–3) proved to be more cytotoxic than cisplatin. All compounds were more cytotoxic to B16F10 cells than to nontumorigenic murine Melan-A melanocyte cells. Interestingly, the selectivity index (SI = IC50 non-malignant cells/IC50 tumor cells) of complex (1), SI = 23, was much higher than that of the parent hydrazone ligand, SI = 9.5. Studies on the interactions of complexes (1–3) with DNA suggested that although (1–3) interact with calf thymus DNA by an intercalative mode, direct covalent binding of silver(I) to DNA probably does not occur. Complexes (1–3) interact in vitro with human serum albumin indicating that these compounds could be transported by albumin.

Molecular dynamics simulations have been performed on the interface between linear saturated hydrocarbons and water in the presence of an asphaltene molecule by measuring the properties such as mean square displacement, radial distribution function, density profile using ave/spatial command, and interfacial tension (IFT) by OPLS and TIP3P FF (force fields). The box of simulation contained one particle of asphaltene, 100 linear saturated hydrocarbons molecules, and 300 water molecules in mixture with interfacial appropriate positioning. The main results show that a small amount of asphaltene in the interface does not significantly alter the data of IFT and that the aliphatic and aromatic groups have preferred orientation.

In this work, the interplay between structure and energetics in some representative phenylnaphthalenes is discussed from an experimental and theoretical perspective. For the compounds studied, the standard molar enthalpies, entropies and Gibbs energies of sublimation, at T = 298.15 K, were determined by the measurement of the vapor pressures as a function of T, using a Knudsen/quartz crystal effusion apparatus. The standard molar enthalpies of formation in the crystalline state were determined by static bomb combustion calorimetry. From these results, the standard molar enthalpies of formation in the gaseous phase were derived and, altogether with computational chemistry at the B3LYP/6-311++G(d,p) and MP2/cc-pVDZ levels of theory, used to deduce the relative molecular stabilities in various phenylnaphthalenes. X-ray crystallographic structures were obtained for some selected compounds in order to provide structural insights, and relate them to energetics. The thermodynamic quantities for sublimation suggest that molecular symmetry and torsional freedom are major factors affecting entropic differentiation in these molecules, and that cohesive forces are significantly influenced by molecular surface area. The global results obtained support the lack of significant conjugation between aromatic moieties in the α position of naphthalene but indicate the existence of significant electron delocalization when the aromatic groups are in the β position. Evidence for the existence of a quasi T-shaped intramolecular aromatic interaction between the two outer phenyl rings in 1,8-di([1,1'-biphenyl]-4-yl)naphthalene was found, and the enthalpy of this interaction quantified on pure experimental grounds as -(11.9 ± 4.8) kJ·mol(-1), in excellent agreement with the literature CCSD(T) theoretical results for the benzene dimer.

Among new potential solvents for lignocellulosic materials, ionic liquids (ILs) are attracting considerable attention. Hence, the knowledge of the thermophysical properties of such fluids is essential for the design of related industrial processes. Therefore, in this work, a set of thermophysical properties, namely, density, viscosity, and refractive index, as a function of temperature, and isobaric thermal expansivity and heat capacities at a constant temperature, were determined for eight ionic liquids with the 1-ethyl-3-methylimidazolium cation combined with the following anions: acetate, methylphosphonate, methanesulfonate, trifluoromethanesulfonate, dicyanamide, thiocyanate, tosylate, and dimethylphosphate. Imidazolium-based ILs were chosen since these are the most studied ionic fluids in biomass dissolution approaches, while a large array of anions was investigated because it was already demonstrated that it is the IL anion that mainly governs the dissolution.

The thermodynamic and structural study of a series of polyphenylbenzenes, from benzene, n(Ph) = 0, to hexaphenylbenzene, n(Ph) = 6, is presented. The available literature data for this group of compounds was extended by the determination of the relevant thermodynamic properties for 1,2,4-triphenylbenzene, 1,2,4,5-tetraphenylbenzene, and hexaphenylbenzene, as well as structural determination by X-ray crystallography for some of the studied compounds. Gas phase energetics in this class of compounds was analyzed from the derived standard molar enthalpies of formation in the gaseous phase. The torsional profiles relative to the phenyl-phenyl hindered rotations in some selected polyphenylbenzenes, as well as the gas phase structures and energetics, were derived from quantum chemical calculations. In the ideal gas phase, a significant enthalpic destabilization was observed in hexaphenylbenzene relative to the other polyphenylbenzenes, due to steric crowding between the six phenyl substituents. A relatively low enthalpy of sublimation was observed for hexaphenylbenzene, in agreement with the decreased surface area able to establish intermolecular interactions. The apparently anomalous low entropy of sublimation observed for hexaphenylbenzene is explained by its high molecular symmetry and the six highly hindered phenyl internal rotations. For the series of polyphenylbenzenes considered, it was shown that the differentiation in the entropy of sublimation can be chiefly ascribed to the torsional freedom of the phenyl substituents in the gas phase and the entropy terms related with molecular symmetry.

The gaseous phase heat capacity of benzoic acid (BA) was proven using the experimental technique called the "in vacuum sublimation/vaporization Calvet microcalorimetry drop method". To overcome known experimental shortfalls, the gaseous phase heat capacity of BA monomer was estimated by ab initio calculations and compared with experimental results. Gaseous phase heat capacities of BA were directly derived via calculated harmonic frequencies obtained by density functional theory (DFT) (B3LYP, BLYP, BP86, with 6-311++G(d,p), TZVP, cc-pVTZ basis sets) and the second-order Moller-Plesset theory, MP2/6-311++G(d,p). To increase the accuracy of estimation of the thermal properties, a procedure based on the calculation of the heat capacity from quantum chemical calculations in combination with a heat capacity balance of isodesmic reactions is described and applied to calculate the gaseous phase heat capacity, C(p,m), of the monomeric species over the temperature range of (298.15 to 600) K. The gaseous phase thermodynamic properties of the monomeric form of the BA were also derived from the assignment of the fundamental vibrational frequencies using experimental IR spectra. An excellent agreement among the experimental gaseous phase heat capacities, the results obtained using the proposed ab initio procedure, and the results derived from the assignment of fundamental vibrational frequencies was found. The results for the monomeric form of the BA, directly or indirectly obtained, and conclusions of this work strongly support the thesis that the gaseous phase heat capacity data as currently found in the literature are underestimated to the order of 20 To.

Accurate targeting of diseased and healthy tissue has significantly been improved by MRI/CT-based navigation systems. Recently, intraoperative MRI navigation systems have proven to be powerful tools for the guidance of the neurosurgical operations. However, the widespread use of such systems is held back by the costs, the time consumption during operation, and the need for MR-compatible surgical devices. Raman spectroscopy is a nondestructive optical technique that enables real-time tissue identification and classification and has proved to be a powerful diagnostic tool in a large number of studies. In the present report, we have investigated the possibility of distinguishing different brain structures by using a single fiber-optic probe to collect Raman scattered light in the high-wavenumber region of the spectrum. For the Raman measurements, 7 pig brains were sliced in the coronal plain and Raman spectra were obtained of 11-19 anatomical structures. Adjacent brain structures could be distinguished based on their Raman spectra, reflecting the differences in their biochemical composition and illustrating the potential Raman spectroscopy holds as a guidance tool during neurosurgical procedures.