Impact of a Multichannel Blocker in Attenuating Intramyocardial Artery Remodeling in Hypertensive Rats through Increased Nitric Oxide Bioavailability.

Dronedarone is recommended for the treatment of atrial fibrillation. However, we do not know its effect on vascular remodeling. This study was designed to assess whether dronedarone has the potential to improve the intramyocardial artery remodeling induced by chronic hypertension. Ten-month-old male spontaneously hypertensive rats (SHR) were randomly assigned to receive dronedarone (100mg/kg) or vehicle. Age-matched maleWistar-Kyoto rats served as controls. After 14 days of treatment, we studied the structure (geometry and fibrosis) of the intramyocardial artery using histological analysis. Nitric oxide (NO) in plasma was analyzed. In the untreated SHR, we observed a significant increase in external diameter, lumen diameter, wall width, cross-sectional area, and collagen volume density, as was expected in the experimental model. Dronedarone induced a significant decrease in wall width, cross-sectional area, and collagen volume density in SHR-D in comparison with untreated SHR. The values obtained in SHR-D were similar in the WKY control group. We found significantly higher NO levels in plasma in SHR-D than in untreated SHR. Dronedarone improves the intramyocardial artery remodeling induced by chronic hypertension in SHR through increased nitric oxide bioavailability.post-print459 K

Does the epiphyseal cartilage of the long bones have one or two ossification fronts?

[Abstract] Epiphyseal cartilage is hyaline cartilage tissue with a gelatinous texture, and it is responsible for the longitudinal growth of the long bones in birds and mammals. It is located between the epiphysis and the diaphysis. Epiphyseal cartilage also is called a growth plate or physis. It is protected by three bone components: the epiphysis, the bone bar of the perichondrial ring and the metaphysis. The epiphysis, which lies over the epiphyseal cartilage in the form a cupola, contains a juxtaposed bone plate that is near the epiphyseal cartilage and is in direct contact with the epiphyseal side of the epiphyseal cartilage. The germinal zone corresponds to a group of cells called chondrocytes. These chondrocytes belong to a group of chondral cells, which are distributed in rows and columns; this architecture is commonly known as a growth plate. The growth plate is responsible for endochondral bone growth. The aim of this study was to elucidate the causal relationship between the juxtaposed bone plate and epiphyseal cartilage in mammals. Our hypothesis is that cells from the germinal zone of the epiphyseal side of the epiphyseal cartilage are involved in forming a second ossification front that is responsible for the origin of the juxtaposed bone plate. We report the following: (a) The juxtaposed bone plate has a morphology and function that differs from that of the epiphyseal trabeculae; (b) on the epiphyseal edge of the epiphyseal cartilage, a new ossification front starts on the chondrocytes of the germinal area, which forms the juxtaposed bone plate. This ossification front is formed by chondrocytes from the germinal zone through a process of mineralisation and ossification, and (c) the process of mineralisation and ossification has a certain morphological analogy to the process of ossification in the metaphyseal cartilage of amphibians and differs from the endochondral ossification process in the metaphyseal side of the growth plate. The close relationship between the juxtaposed bone plate and the epiphyseal cartilage, in which the chondrocytes that migrate from the germinal area play an important role in the mineralisation and ossification process of the juxtaposed bone plate, supports the hypothesis of a new ossification front in the epiphyseal layer of the epiphyseal plate. This hypothesis has several implications: (a) epiphyseal cartilage is a morphological entity with two different ossification fronts and two different functions, (b) epiphyseal cartilage may be a morphological structure with three parts: perichondrial ring, metaphyseal ossification front or growth plate, and epiphyseal ossification front, (c) all disease (traumatic or dysplastic) that affects some of these parts can have an impact on the morphology of the epiphyseal region of the bone, (d) there is a certain analogy between metaphyseal cartilage in amphibians and mammalian epiphyseal cartilage, although the former is not responsible for bone growth, (e) comparative histological and anatomy studies are also warranted, to shed light on the phylogenetic study of epiphyseal cartilage throughout the changes that occur in the animal species

Heating and de-icing function in conductive concrete and cement paste with the hybrid addition of carbon nanotubes and graphite products

This paper aims to study the viability of conductive cement paste and conductive concrete with the hybrid addition of carbon nanotubes (CNT) and graphite powder (GP) as a self-heating material for heating, ice formation prevention and de-icing in pavements. Different heating tests, ice-preventing tests and de-icing tests were performed with cement paste and concrete specimens. Results confirm that the conductive cement composites studied, with the addition of 1% CNT + 5% GP, exhibited heating, de-icing and ice-prevention properties, when applying constant AC/DC voltages between the two end sides of each specimen, with relatively low energy consumption. The main contribution of this work is to achieve a sufficient conductivity level for the development of the heating and de-icing function using this hybrid addition in concrete, which has not been used so far, in order to be applied in real concrete structures.The authors would like to acknowledge financial support received from European Union’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 760940 and from the Generalitat Valenciana (Spain) (AICO/2019/050)

The Effect of Different Oxygen Surface Functionalization of Carbon Nanotubes on the Electrical Resistivity and Strain Sensing Function of Cement Pastes

Different studies in the literature indicate the effectiveness of CNTs as reinforcing materials in cement–matrix composites due to their high mechanical strength. Nevertheless, their incorporation into cement presents some difficulties due to their tendency to agglomerate, yielding a non-homogeneous dispersion in the paste mix that results in a poor cement–CNTs interaction. This makes the surface modification of the CNTs by introducing functional groups on the surface necessary. In this study, three different treatments for incorporating polar oxygen functional groups onto the surface of carbon nanotubes have been carried out, with the objective of evaluating the influence of the type and oxidation degree on the mechanical and electrical properties and in strain-sensing function of cement pastes containing CNTs. One treatment is in liquid phase (surface oxidation with HNO3/H2SO4), the second is in gas phase (O3 treatment at 25 and 160 °C), and a third is a combination of gas-phase O3 treatment plus NaOH liquid phase. The electrical conductivity of cement pastes increased with O3- and O3-NaOH-treated CNTs with respect to non-treated ones. Furthermore, the oxygen functionalization treatments clearly improve the strain sensing performance of the CNT-cement pastes, particularly in terms of the accuracy of the linear correlation between the resistance and the stress, as well as the increase in the gage factor from 28 to 65. Additionally, the incorporation of either non-functionalized or functionalized CNTs did not produce any significant modification of the mechanical properties of CNTs. Therefore, the functionalization of CNTs favours the de-agglomeration of CNTs in the cement matrix and consequently, the electrical conductivity, without affecting the mechanical behaviour.This research was funded by the European Union’s Horizon 2020 Research and Innovation Programme, grant number 760940

Short-Term Treatment with Esmolol Reverses Left Ventricular Hypertrophy in Adult Spontaneously Hypertensive Rats via Inhibition of Akt/NF-κB and NFATc4

Our group has previously demonstrated that short-term treatment with esmolol reduces left ventricular hypertrophy (LVH) in spontaneously hypertensive rats (SHRs). The present study aimed to assess the molecular mechanisms related to this effect. Fourteen-month-old male SHRs were treated intravenously with saline as vehicle (SHR) or esmolol (SHR-E) (300 μg/kg/min). Age-matched vehicle-treated male Wistar-Kyoto (WKY) rats served as controls. After 48 hours of treatment, the hearts were harvested and left ventricular tissue was separated and processed for Western blot analysis to determine the levels of Akt, NF-κB, NFATc4, Creb1, Serca2a, Erk1/2, and Sapk/Jnk. Biomarkers of oxidative stress, such as catalase, protein carbonyls, total thiols, and total antioxidant capacity were evaluated. Esmolol reversed the levels of p-NFATc4, p-Akt, and p-NF-κB in SHRs to the phospholevels of these proteins in WKY rats without modifying p-Erk1/2, p-Sapk/Jnk, p-Creb1, or Serca2a in SHR. Compared with SHR, esmolol increased catalase activity and reduced protein carbonyls without modifying total thiols or total antioxidant capacity. Short-term treatment with esmolol reverses LVH in aged SHRs by downregulation of Akt/NF-κB and NFATc4 activity. Esmolol treatment also increases catalase activity and reduces oxidative stress in SHRs with LVH

Conductive concrete, nanoadditions and functional applications

The addition of a carbon material, such as carbon nanotubes (CNTs) or graphite powder (GP)as conductive ingredients transforms the resulting mixture into a conductive material. This yields the possibility of using the new material for other functions different to the structural one, so that it can be considered a multifunctional material, such as the sensing and heating function. Increasing CNTs or/and GP content decreases the resistivity. Once the percolation threshold is reached it makes no sense to increase % because the resistivity is not anymore significantly changed. Then strain-sensing and heating functions can be can be carried in these conductive cement based materials.This project has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement N°760940

Temperature and humidity influence on the strain sensing performance of hybrid carbon nanotubes and graphite cement composites

Cement composites with hybrid conductive fillers carbon nanotubes (CNT) and graphite products (GP), have been tested as strain sensors under varying temperatures (0 °C–60 °C), and moisture conditions (0%–100% saturation degree (SD)). Cement pastes with 1% CNT and 5% GP (purified expanded graphite) presented resistivity values between 50 and 75 Ohm·cm, and their strain sensing response was observed to be independent of the loading conditions. However, the gage factor increased up to four times for higher temperatures, and was influenced by the temperature time history. Gage factors were also increased when drying the material up to a SD of 71% or with entirely dried samples.This project has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement ID 760940, and from the Generalitat Valenciana grant AICO/2019/050

Conductive concrete, nanoadditions and functional applications

The addition of a carbon material, such as carbon nanotubes (CNTs) or graphite powder (GP)as conductive ingredients transforms the resulting mixture into a conductive material. This yields the possibility of using the new material for other functions different to the structural one, so that it can be considered a multifunctional material, such as the sensing and heating function. Increasing CNTs or/and GP content decreases the resistivity. Once the percolation threshold is reached it makes no sense to increase % because the resistivity is not anymore significantly changed. Then strain-sensing and heating functions can be can be carried in these conductive cement based materials.This project has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement N°760940