Regenerative Neurology and Regenerative Cardiology: Shared Hurdles and Achievements

From the first success in cultivation of cells in vitro, it became clear that developing cell and/or tissue specific cultures would open a myriad of new opportunities for medical research. Expertise in various in vitro models has been developing over decades, so nowadays we benefit from highly specific in vitro systems imitating every organ of the human body. Moreover, obtaining sufficient number of standardized cells allows for cell transplantation approach with the goal of improving the regeneration of injured/disease affected tissue. However, different cell types bring different needs and place various types of hurdles on the path of regenerative neurology and regenerative cardiology. In this review, written by European experts gathered in Cost European action dedicated to neurology and cardiology-Bioneca, we present the experience acquired by working on two rather different organs: the brain and the heart. When taken into account that diseases of these two organs, mostly ischemic in their nature (stroke and heart infarction), bring by far the largest burden of the medical systems around Europe, it is not surprising that in vitro models of nervous and heart muscle tissue were in the focus of biomedical research in the last decades. In this review we describe and discuss hurdles which still impair further progress of regenerative neurology and cardiology and we detect those ones which are common to both fields and some, which are field-specific. With the goal to elucidate strategies which might be shared between regenerative neurology and cardiology we discuss methodological solutions which can help each of the fields to accelerate their development.     

The effect of journey time and stocking density during transport on carcass and meat quality in rabbits

Four hundred and fifty hybrid commercial rabbits (half males and half females) at the end of their productive cycle (82 days old) were transported in cages (98 × 52 × 24 cm, length × width × height) at high or low density (75.5 or 49.0 kg/m² – 15 or 10 animals per cage) on an uncovered truck for 1, 2 or 4 h. Live weight before and after transport as well as slaughter data were recorded for each rabbit. A subset of 180 carcasses were evaluated for meat quality on the basis of meat pH, colour (CIELab system), cooking loss, drip loss and shear force. As a representative of the whole carcass muscle/bone ratio, the left hind leg was separated, dissected and its meat analysed in order to determine its water, protein, ash and lipid content. It was found that a longer journey significantly increases the live weight losses (3.3% vs. 2.0% vs. 1.6% for 4, 2 or 1 h, respectively; P < 0.001), as a result not only of urine and fecal losses, but also of a decrease in carcass weight (P < 0.01) during transport. Ultimate pH (pH_u) was higher and pH drop lower in rabbits transported for 4 h compared to those transported for 2 h (P < 0.05). Moreover, the meat from animals that had undergone the longest journey was more purple-red (P < 0.05), darker (P < 0.0001), and firmer when raw and showed less cooking loss than meat from those that underwent shorter journeys. Transport density did not influence any of the considered parameters and there was no interaction between transport time and density.     

Evaluation of five essential oils from aromatic plants of Cameroon for controlling food spoilage and mycotoxin producing fungi

Five essential oils (EO) extracted from Cymbopogon citratus, Monodora myristica, Ocimum gratissimum, Thymus vulgaris and Zingiber officinale were investigated for their inhibitory effect against three food spoilage and mycotoxin producing fungi, Fusarium moniliforme, Aspergillus flavus and Aspergillus fumigatus. Five strains of each fungus were tested. The agar dilution technique was used to determine the inhibitory effect of each EO on the radial growth of the fungus, and a dose response was recorded. The EO from O. gratissimum, T. vulgaris and C. citratus were the most effective and prevented conidial germination and the growth of all three fungi on corn meal agar at 800, 1000 and 1200 ppm, respectively. Moderate activity was observed for the EO from Z. officinale between 800 and 2500 ppm, while the EO from M. myristica was less inhibitory. These effects against food spoilage and mycotoxin producing fungi indicated the possible ability of each essential oil as a food preservative. A comparative test on the preservative ability of the EO from O. gratissimum and potassium sorbate against A. flavus at pH 3.0 and 4.5 showed that the EO remained stable at both pH, whereas the efficacy of potassium sorbate was reduced at higher pH. We concluded that the EO from O. gratissimum is a potential food preservative with a pH dependent superiority against potassium sorbate, and these are novel scientific information.     

Jarzynski on work and free energy relations: The case of variable volume

Derivations of the Jarzynski equality (JE) appear to be quite general, and applicable to any particle system, whether deterministic or stochastic, under equally general perturbations of an initial equilibrium state at given temperature T. At the same time, the definitions of the quantities appearing in the JE, in particular the work, have been questioned. Answers have been given, but a deeper understanding of the range of phenomena to which the JE applies is necessary, both conceptually and in order to interpret the experiments in which it is used. In fact, domains in which the JE is not applicable have been identified. To clarify the issue, we scrutinize the applicability of the JE to a Hamiltonian particle system in a variable volume. We find that, in this case, the standard interpretation of the terms appearing in the JE is not adequate.     

Out-Of-Plane Metal Coordination for a True Solvent-Free Building with Molecular Bricks: Dodging the Surface Ligand Effect for On-Surface Vacuum Self-Assembly

The desirable self-assembly (SA) of repeated 2D stacked layers requires a “holistic analysis” of three interconnected components: the electrode, the interface, and the molecular component; among them, the contact interface bears the largest burden responsibilities. Epitaxial growth (EG) of coherent 2D+n stacked heterojunction by solvent-free deposition holds great promise, although the feasibility has never been demonstrated given multiple drawbacks (e.g., surface-ligand effect, SLE). Here, it is demonstrated how a coherent 2D+n (n = 3) layered heterorganic film is grown on an archetypal Fe metal electrode. The groundbreaking achievement is the result of the in-vacuum integration of: i) chemical decoupling of the basal organic layer (a Zn^II-tetraphenylporphyrine, ZnTPP) from the metal electrode, ii) 2D-ordering of the ZnTPP commensurate to the substrate, iii) rigid, stoichiometric, and orthogonally arranged, the molecule-to-molecule coupling between ZnTPP and a ditopic linear bridging ligand (i.e., DPNDI) guided by SA coordination chemistry, and iv) sharp (chemical) termination of the layered film.     

High-resolution electron microscopy of Zn- and Bi-related superlattices in ion implanted (1 0 0) Si

Nanosized precipitation in high-dose Zn⁺- and Bi⁺-implanted Si is investigated by high-resolution transmission electron microscopy of cross-sectional specimens. In spite of the different diffusivities of Zn and Bi in Si, their low solubility results in the precipitation of nanosized metallic inclusions revealed as superlattices composed of the host Si matrix and the implanted species.     

Mass Transfer Model for the De-oxidation of Molten Copper

In this paper, we present a mass transfer model that predicts two different mechanisms that control copper de-oxidation: (1) the transport of the reducing gas from the gas bubbles towards the melt/bubble interface, and (2) the transport of dissolved oxygen from the melt towards the melt/bubble interface. The model accounts for gas fluid flow and other process parameters such as lance submergence and nozzle diameter. The model was validated with published data and predictions from our model are in good agreement with the values reported. The key parameters to determine are the mass transfer coefficients of the reducing gas and that of the dissolved oxygen in the melt.