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Urinary tract infections (UTI), which are among the most frequent cases of infectious diseases, mainly affect women. The most common treatment approach involves the use of antibiotics, although this solution is not always the most suitable, mainly because of the resistance that bacterial strains develop. Proanthocyanidins are a class of polyphenols, abundantly contained in cranberry extracts, which have shown beneficial effects in the treatment of urinary tract infections, due to their anti-adhesive properties toward bacteria, with respect to the membranes of the cells of the urothelium and intestine, thus reducing their virulence. In this work, we demonstrate via microscopy and scattering measurements how a mixture of cranberry and chondroitin sulfate can form a crosslinked structure with barrier properties. By using a design of experiment (DOE), we optimized the mass ratio to obtain a precipitate between cranberry extract and chondroitin sulfate in the presence of N-acetylcysteine and hyaluronic acid. By using transepithelial electrical resistance (TEER) chambers, we confirmed the barrier properties of the best mixture obtained with the DOE. Lastly, the antibiofilm action was investigated against five strains of Escherichia coli with different antibiotic sensitivity. The precipitate displayed a variable inhibitory effect in biofilm formation with major effects in UTI with an antibiotic resistance profile.

Bladder cancer is the most common tumor of the urinary system, with a high incidence in the male population. Surgery and intravesical instillations can eradicate it, although recurrences are very common, with possible progression. For this reason, adjuvant therapy should be considered in all patients. Resveratrol displays a biphasic dose response both in vitro and in vivo (intravesical application) with an antiproliferative effect at high concentrations and antiangiogenic action in vivo (intraperitoneal application) at a low concentration, suggesting a potential role for it in clinical management as an adjuvant to conventional therapy. In this review, we examine the standard therapeutical approach to bladder cancer and the preclinical studies that have investigated resveratrol in xenotransplantation models of bladder cancer. Molecular signals are also discussed, with a particular focus on the STAT3 pathway and angiogenic growth factor modulation.

Analytical models of potential energy surfaces are desirable for applications to classical and quantum molecular dynamics simulations, as well as calculation of spectroscopic properties. Here, we present a minimal model based on the expansion in spherical harmonics of the interaction potential between CO2 and CO molecules, both assumed as rigid rotors. This approach consists in determining a minimal number of energy points related to representative mutual orientations of the molecules (configurations) by ab initio calculations. The spherical harmonics expansion represents an exact transformation of these quantum chemical input data. The model permits interpolation and possible implementation of sets of input data at a higher level of theory.

Resveratrol attracts great interest because of the plethora of in vitro effects at the micromolar concentration range. Unfortunately, these effects are difficult to establish in vivo, due to the low concentration of resveratrol reached. This discrepancy is due to the molecules low solubility in water that favors the propensity for an intestinal absorption rather than in the gastric compartment. To address these challenges, we developed a Solid Dispersion of Resveratrol Supported by Magnesium Di Hydroxide formulation (Resv@MDH). This formulation displays increased water solubility and better bioavailability relative to pure resveratrol in the rabbit animal model. In our study, we evaluated the pharmacokinetics profile of resveratrol in six healthy human subjects following 180 mg of oral resveratrol administration, derived from Resv@MDH or pure resveratrol. Free resveratrol was evaluated in the whole blood sample by using HPLC - MS/MS. In comparison with pure resveratrol that displays an increase of the maximum plasma concentration, Cmax at about 90 min and 2 μM, Resv@MDH displays an earlier peak of resveratrol concentration with an increase of Cmax at about 30 min and 6 μM. The different kinetics suggest a main gastric route for resveratrol absorption from Resv@MDH, where, because of its improved dissolution rate, there seems to be a higher propensity for an acidic environment, as opposed to that with pure resveratrol. This conclusion is also supported by the numerical simulation analysis, which considers the principal steps during the oral route administration. Moreover, there is a 2-fold increase in the amount of free resveratrol with respect to pure resveratrol confirming a better bioavailability observed in the animal model. The characteristic feature of the pharmacokinetic profile of Resv@MDH implies that the beneficial properties of resveratrol in human health should be capitalized on it.

We present an analytical model, suitable for molecular dynamics applications, of a five-dimensional potential energy surface, based on the expansion in spherical harmonics, for non-linear-triatomic molecule (C2v) – heteronuclear-diatomic molecule systems, with both molecules having a rigid structure. The method consists in the exact transformation of quantum chemical input data related to a minimal number of significant configurations. This approach is applied to the case study of H2O–HF at various levels of theory. The interaction potential has been analyzed and compared with state-of-art theoretical models. Pros and cons of the method are presented and discussed.

Alternative to conventional structural diagrams that plot dihedral angles of aminoacids in the protein chains, the proposed screen representation is based on significant distances in the aminoacid unit. Here, we report the case of alanine, the simplest chiral aminoacid, both isolated and participating in about fifty peptidic chains, of length included between 43 and 2238 aminoacid units. We present comparison with the most stable conformer in the isolated form (NH2-CH-CH3-COOH), in order to find possible effects in bond lengths due to aminoacid substituents. We have also found that serine is the aminoacid most frequently connected to alanine. Screen points of alanine, when bounded to serine, are displayed and highlighted in order to evidence how this aminoacid, exemplary for the substituent groups, affects the alanine structure.Alternative to conventional structural diagrams that plot dihedral angles of aminoacids in the protein chains, the proposed screen representation is based on significant distances in the aminoacid unit. Here, we report the case of alanine, the simplest chiral aminoacid, both isolated and participating in about fifty peptidic chains, of length included between 43 and 2238 aminoacid units. We present comparison with the most stable conformer in the isolated form (NH2-CH-CH3-COOH), in order to find possible effects in bond lengths due to aminoacid substituents. We have also found that serine is the aminoacid most frequently connected to alanine. Screen points of alanine, when bounded to serine, are displayed and highlighted in order to evidence how this aminoacid, exemplary for the substituent groups, affects the alanine structure.

Large sets of data need to be compacted for classification and extraction of information regarding structural changes of aminoacid units in specific sequences of proteins. The screen is constructed by opposite sides of the virtual tetrahedron built by the six distances between four centers and provides coordinates for a two-dimensional square plot. As alternative e.g. to Ramachandran diagrams based on angles, it may offer greater accuracy and sensitivity. The screen was initially employed to peroxides and persulfides, to monitor the distances relevant to chirality changing processes and successively to show some electric and kinetic properties. The smallest chiral aminoacid, alanine, was therefore chosen for the basic illustration presented here. A virtual tetrahedron is built by the six distances between four centers of the aminoacid skeleton: they do not necessarily coincide with bonds, so a computer program permits their calculation from tabulations of experimental and theoretical data. Here, the screen is applied to treat significant geometrical features of alanine as affected by adjacent aminoacids in peptide chains, as available on protein databases. In this exemplary presentation applications of screen plots are limited to biochemistry: elsewhere have been shown useful in other areas, such as spin networks and the kinematics of a four-bar mechanism.

For the prototypical diatomic-molecule - diatomic molecule interactions H2-HX and H2-X2, where X = F, Cl, Br, quantum-chemical ab initio calculations are carried out on grids of the configuration space, which permit a spherical-harmonics representation of the potential energy surfaces (PESs). Dimer geometries are considered for sets of representative leading configurations, and the PESs are analyzed in terms of isotropic and anisotropic contributions. The leading configurations are individuated by selecting a minimal set of mutual orientations of molecules needed to build the spherical-harmonic expansion on geometrical and symmetry grounds. The terms of the PESs corresponding to repulsive and bonding dimer geometries and the averaged isotropic term, for each pair of interacting molecules, are compared with representations in terms of a potential function proposed by Pirani et al. (see Chem. Phys. Lett. 2004, 394, 37-44 and references therein). Connections of the involved parameters with molecular properties provide insight into the nature of the interactions., 27 pages, 8 figures, 4 tables

The screen is a diagram, alternative to the Ramachandran plot, based on the intermolecular distances. It was successfully adopted to monitor the chirality changing transitions of peroxides and persulfides. In this work, the screen is employed to visualize the dipole moments of peroxides and persulfides determined by quantum mechanical methods in our laboratory. For persulfides racemization times are also presented.

A great variety of data on molecular structure and changes, accumulated both experimentally and theoretically, need be compacted and classified to extract the information arguably relevant to understand the basic mechanisms of chemical transformations. Here a screen for displaying four-center processes is developed and as an illustration applied to conformations involving torsions around O – O and S – S bonds, extending the structural properties previously calculated in this laboratory. The construction of the screen follows from connections recently established between the classical kinematic mechanism – the four-bar linkage – and the basic ingredient of quantum angular momentum theory – the 6j symbol.

The observation of hydrogen peroxide in the interstellar medium represents a remarkable discovery for the astrochemistry community. The prototypical role that this molecule, arguably the simplest chiral molecule, plays in the evolution of life in biospheres, is related to the chirality change transitions associated with the torsional motions around the O – O and the S – S bonds. In this paper, we present an overview on the state-of-art of possible experiments to demonstrate chiral effects discrimination and computational tools applied to peroxides and persulfides.