Smooth Structure Research Articles

Rhamnus prinoides leaf extract loaded polycaprolactone-cellulose acetate nanofibrous scaffold as potential wound dressing: An in vitro study

Rhamnus prinoides leaf contains carbohydrates, saccharides, phenolic acids, and diterpenes with antibacterial, wound-healing, and anti-inflammatory properties. In this study, Rhamnus prinoides leaf extract was successfully incorporated into polycaprolactone-cellulose acetate (PCL-CA) nanofibers through electrospinning technique for the first time. The mats' morphology, diameter, chemical, and crystalline structure were characterized. The study investigated the mats' antibacterial activity, wound healing, cytotoxicity, drug release behaviour, hydrophilicity, and water absorbency properties. The results revealed that the mats exhibited continuous, smooth, without-beads, and interconnected structures, with average fiber diameters ranging from 385 ± 21 nm to 332 ± 74 nm. The antibacterial effeciency was remarkable against S. aureus and E. coli, achieving bacterial reduction percentages exceeding 99 % at concentrations of 3 % and above against S. aureus and 5 % and above against E. coli. Cytotoxic tests showed low-cytotoxicity up to an extract concentration of 7 %. The extract release increases with an increase in concentration. In vitro wound healing assay, the mats enhanced cell migration to the wound area. Additionally, the incorporation of Rhamnus prinoides significantly improved the hydrophilicity and water absorbency of the nanofibers. Overall, the study highlights the mats' broad antimicrobial and wound healing properties with less cytotoxicity, hydrophilicity, and water absorbency, making them promising for use as wound dressings.

Inverse-designed compact silicon waveguide reflector for on-chip resonators

Waveguide reflectors are crucial components in integrated optics and on-chip resonators, with their efficiency and dimensions significantly impacting system performance and integration. This paper presents an compact silicon on-chip waveguide reflector, designed using photonics inverse design, featuring a footprint of only 1.64μm×1.78μm and a simple, smooth structure. The simulation shows a 1 dB bandwidth over 400 nm and a reflectivity above 97.6% in the 1520–1570 nm wavelength range. Experimental measurements, conducted through Fabry-Pérot resonator spectrum analysis, confirm the excellent performance of the waveguide reflector, attaining a reflectivity over 92.8%. Additionally, the study presents two more waveguide reflectors tailored for the 1.31μm and 2μm wavelength, emphasizing the scalability of the design. The compact size and broadband reflectivity characteristics of the waveguide reflector provide increased flexibility in designing cavity lengths and directional couplers, making it a promising choice for applications in resonators and highly integrated photonics systems.

Structural Characterization and Biological Properties Analysis of Exopolysaccharides Produced by Weisella cibaria HDL-4.

An exopolysaccharide (EPS)-producing strain, identified as Weissella cibaria HDL-4, was isolated from litchi. After separation and purification, the structure and properties of HDL-4 EPS were characterized. The molecular weight of HDL-4 EPS was determined to be 1.9 × 10⁶ Da, with glucose as its monosaccharide component. Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) analyses indicated that HDL-4 EPS was a D-glucan with α-(1→6) and α-(1→4) glycosidic bonds. X-ray diffraction (XRD) analysis revealed that HDL-4 EPS was amorphous. Scanning electron microscope (SEM) and atomic force microscope (AFM) observations showed that HDL-4 EPS possesses pores, irregular protrusions, and a smooth layered structure. Additionally, HDL-4 EPS demonstrated significant thermal stability, remaining stable below 288 °C. It exhibited a strong metal ion adsorption activity, emulsification activity, antioxidant activity, and water-retaining property. Therefore, HDL-4 EPS can be extensively utilized in the food and pharmaceutical industries as an additive and prebiotic.

Ultrasound-assisted glycosylation of ovalbumin and dextran conjugate carrier for anthocyanins and their stability evaluation

Anthocyanins (AC) are vulnerable to degradation when affected by external factors. The present study employed ultrasound-assisted glycosylation of ovalbumin (OVA) and dextran (Dex) to generate conjugate carrier for AC to improve its stability. The results showed that sonication significantly improved the progression of Maillard reaction to OVA. Compared to traditional glycosylation, ultrasound treatment showed a higher degree of grafting, a lower number of free-SH, and smaller particle size and uniform distribution. The SDS-PAGE results indicated covalent interaction. Intrinsic fluorescence (INF), Fourier transform infrared spectroscopy (FTIR), and Circular dichroism (CD) analysis results suggested that ultrasound-assisted glycosylation altered the OVA structure. The scanning electron microscope (SEM) and X-ray diffractometer (XRD) observed that the ultrasound-assisted complex had a more compact and smoother structure and protein unfolding were better. The protein solubility increased significantly after glycosylation. Thermal gravimetric analysis (TGA) and Differential scanning calorimetry (DSC) indicated that the glycosylated conjugates can significantly improve the thermal stability of AC In addition, the AC showed an improved processing and storage stability when conjugated with glycosylated carrier. The glycosylated protein-anthocyanins complex may help provide new ideas and scientific basis for the development of naturally sourced anthocyanins-relevant products in pharmaceutical and food industry applications.

Riemannian geometry for efficient analysis of protein dynamics data

An increasingly common viewpoint is that protein dynamics datasets reside in a nonlinear subspace of low conformational energy. Ideal data analysis tools should therefore account for such nonlinear geometry. The Riemannian geometry setting can be suitable for a variety of reasons. First, it comes with a rich mathematical structure to account for a wide range of geometries that can be modeled after an energy landscape. Second, many standard data analysis tools developed for data in Euclidean space can be generalized to Riemannian manifolds. In the context of protein dynamics, a conceptual challenge comes from the lack of guidelines for constructing a smooth Riemannian structure based on an energy landscape. In addition, computational feasibility in computing geodesics and related mappings poses a major challenge. This work considers these challenges. The first part of the paper develops a local approximation technique for computing geodesics and related mappings on Riemannian manifolds in a computationally feasible manner. The second part constructs a smooth manifold and a Riemannian structure that is based on an energy landscape for protein conformations. The resulting Riemannian geometry is tested on several data analysis tasks relevant for protein dynamics data. In particular, the geodesics with given start- and end-points approximately recover corresponding molecular dynamics trajectories for proteins that undergo relatively ordered transitions with medium-sized deformations. The Riemannian protein geometry also gives physically realistic summary statistics and retrieves the underlying dimension even for large-sized deformations within seconds on a laptop.

A novel biodegradable film based on chicken gelatin and κ-carrageenan cross-linked with oxidized phenolic compounds.

Natural and renewable polymers are gradually replacing petroleum-based plastics, mostly as a result of environmental concerns. Moreover, upcycling industrial food waste into new added-value products is a creative approach that is crucial for cleaner and more sustainable manufacturing. The aim of this study was to obtain an environmentally friendly biodegradable film using a combination of k-carrageenan (KCAR) and chicken gelatin (CGEL), which obtained from poultry by-products. The effects of varying concentrations of KCAR (0-2%) on the physical, permeability, textural, thermal, and microstructural properties of CGEL/KCAR composite films were evaluated. The findings demonstrated that an increase in KCAR enhanced the lightness and opacity levels of the films. Water vapor permeability (WVP) values reduced as the KCAR concentration increased. The lowest WVP value (0.0012g.mm/h.m2.kpa) was seen in the treatment with 2% KCAR. Tensile strength (TS) values increased with increasing KCAR. The films' thermal stability was increased by the addition of KCAR. Microstructure assessments revealed a more compact and smooth structure in the KCAR-containing treatments, indicating improvements in WVP, thermal stability, and TS. Compared to the commercial cattle gelatin film, the CGEL film had higher TS and lower water solubility (WS). Overall, this study showed that the physical, mechanical, barrier and thermal and microstructural qualities of gelatin-based films may be enhanced by combining CGEL and KCAR to create an effective biodegradable film. Moreover, the comparison study between commercial cattle and chicken gelatin films revealed that cross-linked chicken gelatin films would be a suitable alternative for bovine gelatin films in the production of biodegradable film.

A new dynamic state estimation method for distribution networks based on modified SVSF considering photovoltaic power prediction

The fluctuations brought by the renewable energy access to the distribution network make it difficult to accurately describe the state space model of the distribution network’s dynamic process, which is the basis of the existing dynamic state estimation methods such as the Kalman filter. The inaccurate state space model directly causes an error of dynamic state estimation results. This paper proposed a new dynamic state estimation method which can mitigates the impact of renewable energy fluctuation by considering PV power prediction in establishing distribution network state space model. Firstly, the proposed method mitigates the impact of renewable energy fluctuation by considering PV power prediction in establishing distribution network state space model. Secondly, SVSF filter is introduced to achieve more accurate estimation under noise. The case study and evaluations are carried out based on MATLAB simulation. The results prove that the smooth variable structure filter with photovoltaic power prediction has a better dynamic state estimation effect under the fluctuation of the distribution network compared with the existing Kalman filter.

Tapioca starch/konjac gum-based composite film incorporated with nanoliposomes encapsulated grape seed oil: Structure, functionality, controlled release and its preservation role for chilled mutton

In this study, grape seed oil nanoliposomes (GSO-NLs) were constructed and doped into tapioca starch/konjac gum composite films (TK-GSO-NLs) to evaluate the preservation of chilled mutton. The results showed that the GSO-NLs have a good spherical or rounded state and good stability. The doping of GSO-NLs resulted in a smooth, flat, and dense structure on the surface and cross-section of the TK films. The TK-GSO-NLs showed the best compatibility among the components, with excellent mechanical and barrier properties. FTIR and XRD confirmed the presence of ionic bonds between the components, further improving the copolymer crystal structure. Notably, the packaging material provided ideal antioxidant and bacteriostatic stability as well as delayed GSO release. This packaging could effectively maintain the quality of chilled mutton and prolong the shelf-life to 15 days. The study provides ideas for the design of green and active food packaging and for extending the shelf life of meat.

A high‐power, high‐isolation, dual‐polarised planar phased array antenna

AbstractA high‐power, high‐isolation, dual‐polarised planar phased array antenna is presented. Based on a multi‐layer microstrip structure, two sets of polarisation ports are fed through orthogonal slot coupling, achieving high isolation and low cross‐polarisation. Double‐layer radiation patches and cavity interlayers are used to expand the bandwidth and increase the gain. Metal vias are added around microstrip feeders and between array units to suppress surface waves, thereby improving the scanning performance of the phased array. A smooth gradient microstrip structure is designed to improve the power capacity while realising broadband impedance matching. The measured results show that in the 8–10 GHz frequency band, the isolation of the dual polarisation ports is greater than 50 dB, and the impedance bandwidth reaches 22.2%, with active VSWR <1.5 when not scanning. Both sets of polarisation can achieve 2‐D beam scanning in the range of E‐plane ±20° and H‐plane ±40° without grating lobes, maintaining the scan loss below 2.4 dB, cross‐polarisation below −20 dB and active VSWR <2. Each unit achieves a high gain of 7.4 dB and large power capacity of 5 kW; so the entire 8 × 8 phased array can achieve a main lobe gain of 25.5 dB and realise high‐power directional radiation with the effective isotropic radiated power of 92.5 dBm. The proposed planar antenna has a low profile of 5.5 mm (0.17λ0).

Copper nanoparticles incorporated visible light-curing chitosan-based hydrogel membrane for enhancement of bone repair

Alveolar bone defects caused by tumor, trauma and inflammation can lead to the loss of oral function and complicate denture restoration. Currently, guided bone regeneration (GBR) barrier membranes for repairing bone defect cannot effectively promote bone regeneration due to their unstable degradation rate and poor antibacterial properties. Furthermore, they require additional tailoring before implantation. Therefore, this study developed a visible light-curing hydrogel membrane (CF–Cu) comprising methacrylated carboxymethyl chitosan (CMCS-MA), silk fibroin (SF), and copper nanoparticles (Cu NPs) to address these shortcomings of commercial membranes. The CF-Cu hydrogel, characterized by scanning electron microscopy (SEM), a universal testing machine, and swelling and degradation tests, demonstrated a smooth porous network structure, suitable swelling ratio, biodegradability, and enhanced mechanical strength. Cytotoxicity and hemolysis tests in vitro demonstrated excellent cyto- and hemo-compatibility of the CF-Cu hydrogel extracts. Additionally, evaluation of antibacterial properties in vitro, including colony forming unit (CFU) counts, MTT assays, and live/dead fluorescence staining, showed that the CF-Cu hydrogel exhibited excellent antibacterial properties, inhibiting over 80% of S. aureus, S. mutans, and P. gingivalis with CF-1Cu hydrogel compared to the control group. Moreover, evaluation of osteogenic differentiation of rBMSCs in vitro suggested that the CF-1Cu hydrogel significantly improved alkaline phosphatase (ALP) activity and the mineralization of extracellular matrix, up-regulating the expressions of osteogenesis-related genes (Runx2, ALP, Col-1, OPN and BSP). In summary, these results indicated that CF-1Cu hydrogel exhibited excellent cytocompatibility, antibacterial and osteogenic properties in vitro. Therefore, the CF-1Cu hydrogel holds potential as a viable material for application in GBR procedures aimed at addressing bone defects.

Computational analysis of piston shape effects on in-cylinder gas flow, fuel-charge mixing, and combustion characteristics in a two-stroke rod-less spark ignition opposed-pistons engine

Compared with the traditional in-cylinder direct-injection spark ignition engine, the side-injection and side-spark-ignition characteristics of the two-stroke opposed-piston engine increase the ignition kernel offset and flame propagation distance. Increasing the flame propagation speed can to some extent solve the drawbacks caused by the non-central arrangement of spark plugs. The combustion chamber structure plays a crucial role in gas flow, fuel-charge mixing, and combustion characteristics. Therefore, three pistons were designed and comparatively analyzed in this study. The results show that: The pancake piston is beneficial to maintaining the intake swirl strength due to its simple and smooth spherical arc structure. The swirl strength of the pit and pit-guided piston decreases obviously, and the tumble strength can be maintained well. Compared to pancake and pit-guided pistons, the average TKE for the pit piston increased by approximately 25%, with a more concentrated distribution at the spark timing. The pancake piston exhibits the best scavenging performance, reducing the residual exhaust gas ratio by 2.1% and fresh air loss by 3.3% to the pit piston. A stable ignition core can be formed at the spark timing, but significant differences are observed in the flame propagation process for three pistons. Compared to the pit-guided piston, the pit piston has a 0.3% decrease in the indicated thermal efficiency, but a 13.1% decrease in combustion duration, which reduces knock tendency.

Preparation of surfactant‐assisted polycaprolactone/κ‐carrageenan nanofibres

AbstractThe objective of this work was to fabricate nanofibres composed of polycaprolactone (PCL) and κ‐carrageenan (kC) by employing an anionic surfactant, sodium bis(2‐ethylhexyl) sulfosuccinate (AOT). This study examined the role of the surfactant in PCL/kC/AOT (hybrid) nanofibre preparation using SEM, AFM, Fourier transform infrared spectroscopy, XRD and DSC. The wettability and water uptake percentage of the nanofibres were investigated. An antimicrobial study was conducted against bacterial strains using a colony‐counting assay, and changes in bacterial morphology were monitored using TEM. The results demonstrated that the hybrid nanofibres had a uniform and smooth structure, which might be attributed to the improved compatibility between polymers in the presence of the surfactant. The incorporation of AOT in the matrix resulted in a reduction in the mean fibre diameter and surface roughness. The hybrid nanofibres increased water absorbency is evidence of their high hydrophilicity, which can be explained by the simultaneous impact of kC and AOT. The hybrid nanofibres exhibited effective activity against Staphylococcus aureus and Escherichia coli. © 2024 Society of Chemical Industry.

Enhancing the Phase Crystallinity of Buried Layer Perovskites through Organic Salt Molecule‐Assisted Crystal Growth

The performance and stability of perovskite solar cells rely crucially on the purity of their active perovskite phase. While the two‐step method has emerged as a well‐known technique for fabricating high‐performance cells, it suffers from significant PbI2 phase impurities at the buried layer due to inefficient diffusion of cationic molecules into the preprepared PbI2 layer. Herein, a simple yet highly effective method is presented to boost phase purity within the buried layer by introducing formamidinium iodide (FAI) seed molecules into the underlying PbI2 layer. X‐Ray diffraction analysis result reveals that this process significantly reduces the PbI2 phase and enhances the purity of the perovskite's phase. It is also observed that this technique can produce perovskite layer with a remarkably smooth surface structure and large interconnected crystal grains, forming a continuous layer. These characteristics are subjected to further enhancement when hexamethylenetetramine molecules are concurrently introduced with FAI into the PbI2 layer. Solar cells fabricated using this method, with an active area of 0.1 cm2, achieve a remarkable power conversion efficiency of up to 24.52% with Voc as high as 1.18 V, representing a substantial improvement over cells produced using the standard two‐step method, which attains only 22.18% efficiency. With its simple yet impactful approach, the present method should find widespread adoption in the production of high‐performance perovskite solar cells.

Electrospun O-quaternary ammonium chitosan/polyvinyl alcohol nanofibrous film by application of Box–Behnken design response surface method for eliminating pathogenic bacteria

In this study, O-quaternary ammonium chitosan (O-HTCC) containing bicationic antibacterial active groups was synthesized to develop an O-HTCC/PVA porous nanofibrous film to enhance antibacterial activity, leveraging surface modification and nano-porous structure design. Uniform and smooth nanofibrous structures (average diameter: 72–294 nm) were successfully obtained using a simple and feasible electrospinning method. A response surface model via Box-Behnken design (BBD) was used to clarify the interaction relationship between O-HTCC fiber diameter and three critical electrospinning parameters (O-HTCC concentration, applied voltage, feed flow rate), predicting that the minimum O-HTCC fiber diameter (174 nm) could be achieved with 7 wt% of O-HTCC concentration, 14 kV of voltage, and 0.11 mL/h of feed flow rate. Linear regression (R2 = 0.9736, Radj2 = 0.9716) and the Anderson Darling test demonstrated the excellent fit of the RSM-BBD model. Compared to N-HTCC/PVA nanofibrous film, the O-HTCC/PVA version showed increased growth inhibition and more effective antibacterial efficacies against Escherichia coli (E. coli) (~;86.34 %) and Staphylococcus aureus (S. aureus) (~;99.99 %). DSC revealed improved thermal stability with an increased melting temperature (238 °C) and endothermic enthalpy (157.7 J/g). This study holds potential for further development of antibacterial packaging to extend food shelf-life to reduce bacterial infection.

Growth and optimization of spray coated Cu2BaSnS4 thin films for solar photovoltaic application

Quaternary multicomponent Cu2BaSnS4 (CBTS) has emerged as a potential absorber material due to its abundant and nontoxic constituents, high absorption coefficient (10−4 cm−1) and suitable bandgap (1.5–2.0 eV) for the solar photovoltaic application. In this study, polycrystalline CBTS thin layers have been deposited by a typical spray pyrolysis technique on glass substrates using different substrate temperatures (Ts = 200, 250, 300 and 350 °C) followed by annealing in a sulfur-rich atmosphere at 550 °C under an argon flow. The (micro-)structural, compositional, and optical properties of both types of films have been studied. Analysis of x-ray diffractogram (XRD) patterns for all acquired films showed the presence of polycrystalline CBTS alongside various secondary phases, including Cu2SnS3 being predominant. Nonetheless, the XRD of the films deposited at 250 °C and annealed at 550 °C showed only the CBTS phase. Raman spectroscopy confirm the formation of the trigonal phase of CBTS. The presence of Cu, Ba, Sn and S in CBTS thin films was confirmed by X-ray photoelectron spectroscopy and Energy-dispersive X-ray spectroscopy. Scanning electron micrographs show a smooth and dense structure with enhanced crystallinity and improved uniformity. Overall, the physical properties of CBTS thin films were found to be spray deposition temperature dependent. An appropriate optical band gap of 1.6 to 1.8 eV and a compact structure indicate their prospective for solar cell applications.

Magnetostrictive strain-sensitivity synergy for laser-beam powder bed fusion processed Fe81Ga19 alloys by magnetic field annealing

Magnetostrictive Fe–Ga alloys have been demonstrated potentialities for numerous applications, whereas, suffering a tradeoff between large magnetostrictive strain and high sensitivity. Herein, bulk polycrystalline Fe81Ga19 alloys were prepared by laser-beam powder bed fusion (LPBF) and then annealed in magnetic field for manipulating the comprehensive magnetostrictive properties. Results indicate that <001> oriented grains are developed in the LPBF-prepared Fe81Ga19 alloys due to high temperature gradient. After magnetic field annealing (MFA), the magnetic domains within the alloys gradually transformed into well-arranged stripe domains, especially, flat and smooth 90° domains were established in the alloys annealed at 2600 ​Oe. As a result, the induced <001> orientation grains and 90° domains contributed to an improved effective magnetic anisotropy constant (57.053 ​kJ/m3), leading to an enhanced magnetostrictive strain of 92 ​ppm. Moreover, the MFA-treated alloys also displayed enhanced magnetostrictive sensitivity (0.097 ​ppm/Oe) owing to the smooth domain structures and low dislocation densities, demonstrating a fruitful strain-sensitivity synergy. In addition, good magnetostrictive dynamic response and enhanced compressive yield strength were also observed for the prepared alloys. This work demonstrates that LPBF and MFA might be an attractive strategy to resolve the tradeoff between strain and sensitivity, providing a basis for the preparation of high-performance magnetostrictive materials.

A Tris(terpyridine) Ligand-based Metal Coordination Nanosheet as Electrode Material with Good Supercapacitor Performance

In this work, through a facile liquid–liquid (L–L) interfacial-assisted synthesis at room temperature, a new two-dimensional (2D) metal coordination nanosheet Co-TPY-LB has been synthesized by the coordination between Co2+ ion and 1,3,5-tris(4′-tripyridinylphenyl)benzene (Tris-tpy). The flat and smooth sheet structure with a thickness of 83.3 nm and a hexagonal structure with a lattice spacing of about 0.206 nm for the as-fabricated nanosheet Co-TPY-LB has been identified by AFM and HRTEM respectively, providing a large number of redox sites and ion diffusion channels. The fabricated Co-TPY-LB have been used as electrodes and exhibit the highest capacity of 2741.5 F g−1 at the current density of 1 A g−1, an excellent cycling stability with 97.6% capacity retention after 1000 cycles at the current density of 10 A g−1. Meanwhile, the assembled asymmetric supercapacitor with Co-TPY-LB as the positive electrode shows a high energy density 73.6 Wh kg−1 at a power density of 4800 W kg−1 as well as an excellent cycle stability of 92.9% capacity retention after 5000 cycles. Our work provides a controllable synthesis for the construction of 2D metal coordination nanosheet to overcome some defects of 2D nanosheet by traditional synthesis, leading such bottom-up nanosheet to a promising application in energy storage.Graphical

High-order second-generation wavelet upwind schemes with multiresolution self-adaptive capabilities for hyperbolic conservation laws

We introduce a novel system of high-order wavelet collocation upwind schemes utilizing a broad class of second-generation wavelets for hyperbolic conservation laws. These schemes possess multiresolution self-adaptive capabilities and are integrated into a meshfree framework. Unlike traditional high-order schemes that necessitate frequent variable transformations between physical and characteristic spaces involving numerous local projections, our schemes enable the direct discretization of relevant spatial derivatives in the physical space. The newly proposed schemes make the most use of wavelet properties, i.e., applying asymmetrical interpolating wavelets to achieve the upwind property and utilizing the symmetrical second-generation wavelets to preserve shapes of functions and obtain higher data compression rates. Numerical tests of which solutions contain strong discontinuities and different scale smooth structures are conducted to demonstrate the enhanced performance of the proposed schemes based on the second-generation wavelets. The proposed schemes can utilize only 9 % of the nodes in the WENO5 scheme to yield similar results when addressing the advection of a square wave and achieve the convergent solution for the two interacting blast waves problem without local characteristics projection. In comparison to conventional methods and wavelet upwind schemes based on the interpolating wavelets we previously introduced, the newly proposed schemes exhibit a significantly higher data compression rate and yield substantial computational savings without compromising accuracy.

Visual Mnemonics and Gamification

This learning representation is an innovative approach to teaching muscle physiology in a first-year medical school curriculum, utilizing assets from the Medimon game-based website. Medimon is a game designed to enhance students' preference and retention of medical concepts through interactive and visually engaging game contexts. The Medimon game experience allows students to (a) engage with characters representing various physiological components, (b) explore buildings designed to align with visual mnemonics, and (c) reinforce knowledge via game activities of muscle physiology, including muscle, cardiac, and smooth muscle structure and function. By leveraging the detailed visual mnemonics of the game, we implemented Medimon game assets into a presentation on muscle physiology to supplement existing presentation materials and promote long-term retention of muscle physiology.

Evaluating the therapeutic effect of vitamin D and nerolidol on lung injury due to experimental myocardial infarction: The potential role of asprosin and spexin

Injury to internal organs caused by myocardial infarction (MI), although often neglected, is a very serious condition which damages internal organs especially the lungs. Changes in microcirculation can begin with acute lung injury and result in severe respiratory failure. The aim of this study was to create new approaches that will explain the pathophysiology and treatment of the disease by examining the therapeutic effects of vitamin D (VITD) and Nerolidol (NRD) on the injuries of the lungs caused by MI, and their relationship with asprosin / spexin proteins. MethodsSix groups of seven experimental animals each were constituted. Control, VITD (only 50 IU/day during the experiment), NRD (only 100 mg/kg/day during the experiment), MI (200 mg/kg isoproterenol was administered to rats as a single dose subcutaneously), MI+VITD (200 mg/kg isoproterenol +50 IU/day) and MI+NRD (200 mg/kg isoproterenol +100 mg/kg/day) were the six (6) groups constituted. Tissues were analyzed using histopathological and immunohistochemical methods, whereas serum samples were analyzed using ELISA method. ResultsThe result of the histopathological study for the MI group showed an observed increase in inflammatory cells, congestion, interalveolar septal thickening, erythrocyteloaded macrophages and fibrosis in the lung tissues. The treatment groups however recorded significant differences with regards to these parameters. In the immunohistochemical analysis, expressions of asprosin and spexin were observed in the smooth muscle structures and interalveolar areas of the vessels and bronchioles of the lung, as well as the bronchiole epithelium. There was no significant difference between the groups in terms of asprosin and spexin expression in the bronchiol epithelium.When immunohistochemical and serum ELISA results were examined, it was observed that asprosin levels increased significantly in the lung tissues of the MI group compared to the control group, decreased significantly in the treatment groups treated with Vitamin D and NRD after MI. While spexin decreased significantly in the MI group compared to the control group, it increased significantly in the MI+VİTD group, but did not change in the MI+NRD group. ConclusionIt was observed that serious injuries occurred in the lungs due to myocardial infarction and that, VITD and NRD treatments had a curative effect on those injuries. It was also observed that Asprosin and Speksin proteins can have effect on mechanisms of both injury and therapy of the lung. Furthermore, the curative effects of VITD are dependent on the expression of asprosin and spexin; whereas the observation indicated that nerolidol could be effective through asprosin-dependent mechanisms and specisin by independent mechanisms.