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Abstract Hydroxyapatite (HA) is an extensively used biomaterial for dental and orthopaedic applications because of its biocompatibility and biomimetic nature. HA is extensively used as a bone-graft substitute. HA bone graft substitutes of bovine or synthetic origins have been extensively studied. However, caprine-based HA has not been explored. In this study, we aimed to determine the utilization of goat bone-derived HA for commercial applications. HA from caprine bone and teeth was isolated using thermal calcination. The developed HA can be used as a bone graft substitute. Chemical characterization of the isolated HA was carried out using Fourier transform infrared spectroscopy, X-Ray Diffraction, Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy. The biocompatibility and apatite formation of isolated HA were assessed using MG-63 cells, MC3T3-E1, L929 cells, MSCs, adipose derived stem cells, human dermal tissue derived fibroblast cells and osteoblast-like cell line, The studies demonstrate that HA support cell adhesion and osteogenic properties. To improve sheep, lamp, or caprine bone-derived HA, several other composites have been developed with MgO2, ZrO2, ZnO2, and other polymeric substances. 3D printed technology was used to develop a bioink using sheep-derived HA and printed the composite scaffold as a bone graft substitute. Furthermore, the biomedical applications of sheep-derived HA been studied in terms of their antimicrobial activity, bone-forming ability, and wound healing applications. Sheep-, goat-, and caprine-derived HA are still underutilized and require further research to develop commercial possibilities and sustainable raw materials for HA-based bone graft substitutes.

Despite present antiviral agents that can effectively work against HIV-1 replication, side effects and drug resistance have pushed researchers toward novel approaches. In this context, there is a continued focus on discovering new and more effective antiviral compounds, particularly those that have a natural origin. Polysaccharides are known for their numerous bioactivities, including inhibiting HIV-1 infection and replication. In the present study, phosphorylated chitosan oligosaccharides (PCOSs) were evaluated for their anti-HIV-1 potential in vitro. Treatment with PCOSs effectively protected cells from HIV-1-induced lytic effects and suppressed the production of HIV-1 p24 protein. In addition, results show that PCOSs lost their protective effect upon post-infection treatment. According to the results of ELISA, PCOSs notably disrupted the binding of HIV-1 gp120 protein to T cell surface receptor CD4, which is required for HIV-1 entry. Overall, the results point out that PCOSs might prevent HIV-1 infection at the entry stage, possibly via blocking the viral entry through disruption of virus–cell fusion. Nevertheless, the current results only present the potential of PCOSs, and further studies to elucidate its action mechanism in detail are needed to employ phosphorylation of COSs as a method to develop novel antiviral agents.

The aim of the present study is to investigate the anti-inflammatory effect of gallic acid grafted onto COS chains (GA-COS), focusing on the reduction of nitric oxide production, downregulation of inflammatory signals such as inducible nitric oxide synthase (iNOS), gene expression of cytokines such as TNF-α, IL-1β, IL-6, and nuclear factor kappa B (NF-κB) signalling, including the p50 and p65 subunits. The anti-inflammatory effect is mediated through the reduction of nitric oxide production and downregulation of inflammatory proteins such as inducible nitric oxide synthase (iNOS), gene expression of cytokines like TNF-α, IL-1β, IL-6, and nuclear factor kappa B (NF-κB) signalling, including the p50 and p65 subunits. Target proteins were identified by western blot analysis with specific monoclonal antibodies. The levels of gene expression were determined by the RT-PCR method. The results demonstrate that GA-COS effectively reduces nitric oxide generation and downregulates iNOS protein and cytokine expression and NF-κB signalling in lipopolysaccharide (LPS) -induced RAW 264.7 cells. GA-COS exhibits significantly enhanced anti-inflammatory activity compared to the free chitooligosaccharide chain. This study lays the groundwork for future research to demonstrate that GACOS holds significant potential as a novel compound for the prevention of inflammatory diseases.

Abstract The coupling between magnons and phonons and the associated phenomena have long been a focus of research in condensed matter physics. Contrary to its recognized role in magnon relaxation, its impact on phonon transport remains largely unexplored. Here, we fill this gap by investigating the effect of magnon-phonon coupling on phonon excitation, relaxation, and transport with magneto-optical reflectometry. Through simultaneous measurements of magnon and phonon populations in magnetic insulator thulium iron garnet, we observe the excitation of excessive phonons driven by non-equilibrium magnons, demonstrating the magnetic control of phonons. Furthermore, our time-resolved experiments reveal the magnetic field-dependent phononic thermal conductivity, signaling the potential of magnetic manipulation of heat transport. Our finding indicates that phonons can be controlled by magnetic means through magnon-phonon coupling and thereby opens a new avenue to harness magneto-thermoelectric effects in magnetic insulators.

We present a theoretical study of the scattering of spin waves by a domain wall (DW) in a ferrimagnetic (FiM) spin chain in which two sublattices carry spins of unequal magnitudes. We find that a narrow but atomically smooth FiM DW exhibits a different behavior in comparison with similarly smooth ferromagnetic and antiferromagnetic DWs due to the inequivalence of the two sublattices. Specifically, for sufficiently weak anisotropy, the smaller spin at the center of the DW is found to become precisely normal to the easy axis, selecting an arbitrary direction in the xy plane and thereby breaking the U(1) spin-rotational symmetry spontaneously. This particular form of a FiM DW does not occur in antiferromagnetic systems and is shown to lead to a strong dependence of spin-wave scattering pattern on the state of polarization of the spin wave, which can be either right-handed or left-handed, suggesting the utilization of such a narrow DW as a spin-wave filter. Moreover, we find that in the case of an atomically sharp DW, where all the spins point either up or down due to strong easy-axis anisotropy and therefore the polarization of the spin wave is conserved upon transmission, the wave vector of the spin-wave changes after passing through the DW leading to a change in the group velocity of the spin wave. This change of the wave vector indicates the acceleration or deceleration of the spin waves and thus a sharp FiM DW could serve as a spin-wave accelerator or decelerator in spintronics devices, offering a functionality absent in a ferromagnetic and an antiferromagnetic counterpart. Our results indicate that FiM spin textures can interact with spin waves distinctly from ferromagnetic and antiferromagnetic counterparts, suggesting that they may offer spin-wave functionalities that are absent in more conventional magnets.