Arunachalam Thirugnanam

Piezoelectric biomaterials such as chitosan and β‐glycine mimic endogenous electrical signals to aid wound healing, yet the role of surface‐functionalized TiO ₂ nanoparticles in enhancing the properties of glycine–polymer composites remains unexplored. This study incorporates TiO ₂ nanoparticles functionalized with citric acid (TiO ₂ ‐CA) into a chitosan‐β‐glycine matrix to improve wound‐healing performance. Films containing 4, 8, and 12 wt% TiO ₂ ‐CA are prepared by solvent casting and evaluated for their physicochemical and in vitro biological properties. XRD confirms the phases of glycine crystals and TiO ₂ nanoparticles, while FESEM shows the distribution of TiO ₂ ‐CA nanoparticles within the film. The 12 wt% film exhibits a 40.6% higher contact angle, an increase in tensile strength from 4.93 to 10.99 MPa, a 200% reduction in swelling, a 90% reduction in protein adsorption, exhibits good cell viability, and accelerates wound closure in the scratch assay test compared to the control. Oscilloscope measurements reveal that the 12 wt% film produces voltage outputs 90%, 33%, and 24% higher during finger stretching, tapping, and bending, respectively. These results suggest that the films are promising for advanced wound healing by mimicking electrical signals to promote tissue regeneration.

Plantar heel pain (PHP) is the most predominant foot pathological condition persisting among people with obesity. Conventional techniques measure the heel pad's (HP) thickness, stiffness, and elasticity by subjecting a known force under static conditions. However, it falls short of assessing the HP under natural physiological loading conditions. Therefore, the present study investigates the biomechanical characteristics of the HP during dynamic plantarflexion movement (body weight unloading and loading) using a 3D motion capture system and a multiaxial force plate. Participants were selected and divided into three categories based on body mass index (BMI): healthy weight (HW), overweight (OW), and obese (OB). Each category consisted of thirty male and thirty female participants. The retroreflective markers were placed on the HP, and participants were instructed to perform the plantarflexion movement on the force plate. The biomechanical output parameters, such as HP deformation and compliance, were calculated for different phases of plantarflexion movement along the vertical and horizontal directions. Statistical analysis was performed at a 95% confidence level. The study revealed that male and female participants in the OB category exhibited less HP deformation than those in the HW and OW categories. Male and female participants in the HW category showed higher HP compliance than those in the OB category. The magnitude of HP compliance was higher in the vertical direction than in the horizontal direction. HP stiffness increases with higher BMI (OB > OW > HW) and leads to PHP. The study revealed that males have lower HP compliance and deformation than females. The findings provide a better understanding of HP characteristics across different weight groups, which could be used to develop customized soles that absorb shock during dynamic activity and reduce heel pain among the population with obesity.

Plantar heel pain (PHP) is the most common problem experienced by most individuals. The overweight and obese people are more inclined to musculoskeletal foot disorders or PHP. While conventional methods can measure stiffness and thickness to analyze heel pads (HP), they are ineffective in assessing HP under natural dynamic conditions. Therefore, this study aims to investigate the HP in real-time during dynamic plantarflexion movement (baseline, unloading, and loading) using a 3D motion capture system and an indigenous force plate. A total of fifteen healthy participants were selected based on their BMI and categorized into normal weight (NW), overweight (OW), and obese (OB) categories. The retroreflective markers were placed on the HP region, and volunteers were asked to perform plantarflexion movements. The biomechanical output measures, such as stiffness and displacement of HP, were calculated and compared between groups. Statistical analysis was performed and validated based on significant differences. The study reveals that the stiffness of HP increases with an increase in BMI, which eventually causes heel pain in OB participants. Based on the stiffness and deformation in the soft tissues of HP, the study results can be used to design a suitable sole to improve comfort and reduce heel pain.

Coronary artery disease treatments like coronary artery bypass grafting and percutaneous transluminal coronary angioplasty have several drawbacks, such as their invasive nature. Two main types of stents, bare metal stents (BMSs) and drug-eluting stents (DESs), are implemented to overcome these difficulties. The BMS offers strong mechanical support but can cause in-stent thrombosis and restenosis. Conventional DES, comprising a metal platform coated with drug-conjugated polymers, initially lowers restenosis but can cause early thrombosis and late in-stent restenosis. To overcome these limitations, biodegradable DESs are being explored to provide short-term support without long-term complications. However, biodegradable metal-based DES can trigger immunogenic reactions when degraded. The next generation of stents is shifting toward bioresorbable polymer-based DES because their degradation products are compatible with the metabolic system of the body. This review discusses the in vivo degradation mechanisms of bioresorbable polymers such as polyglycolic acid, polylactic acid, and polycaprolactone (PCL) acid polymers. It was observed that these polymers primarily degrade via ester bond hydrolysis, influenced by polymer properties such as molecular weight, morphology, glass transition temperature, and composition. Additionally, this overview highlights ongoing advancements in bioresorbable polymer-based scaffolds like DESolve[ ]NX and FANTOM[ ]. These bioresorbable scaffolds are fabricated from poly-L-lactide acid and desamino tyrosine-based polymers, respectively. Polylactic-co-glycolic acid-coated platinum–chromium stents have also demonstrated effective performance, being fully absorbed within 4–6 months postimplantation. Moreover, PCL acid-based drug-eluting bifurcation stents have shown promise in treating cardiovascular diseases. However, the review emphasizes the necessity for continued research to address the existing challenges and enhance patient outcomes.

Biodegradable drug‐eluting stents (DESs) are gaining importance owing to their attractive features, such as complete drug release to the target site. Magnesium (Mg) alloys are promising materials for future biodegradable DESs. However, there are few explorations using biodegradable Mg for cardiovascular stent application. In this present study, sirolimus‐loaded poly D, L‐lactic‐co‐glycolic acid (PLGA)‐coated/ sirolimus‐fixed/AZ91 Mg alloy‐based substrate was developed via a layer‐by‐layer approach for cardiovascular stent application. The AZ91 Mg alloy was prepared through the squeeze casting technique. The casted AZ91 Mg alloy (Mg) was alkali‐treated to provide macroporous networks to hold the sirolimus and PLGA layers. The systematic characterization was investigated via electrochemical, optical, physicochemical, and in‐vitro biological characteristics. The presence of the Mg₁₇Al₁₂ phase in the Mg sample was found in the x‐ray diffraction system (XRD) spectrum which influences the corrosion behavior of the developed substrate. The alkali treatment increases the substrate's hydrophilicity which was confirmed through static contact angle measurement. The anti‐corrosion characteristic of casted‐AZ91 Mg alloy (Mg) was slightly less than the sirolimus‐loaded PLGA‐coated alkali‐treated AZ91 Mg alloy (Mg/Na/S/P) substrate. However, dissolution rates for both substrates were found to be controlled at cell culture conditions. Radiographic densities of AZ91 Mg alloy substrates (Mg, Mg/Na, and Mg/Na/S/P) were measured to be 0.795 ± 0.015, 0.742 ± 0.01, and 0.712 ± 0.017, respectively. The star‐shaped structure of 12% sirolimus/PLGA ensures the bioavailability of the drugs. Sirolimus release kinetic was fitted up to 80% with the “Higuchi model” for Mg samples, whereas Mg/Na/S/P showed 45% fitting with a zero‐order mechanism. The Mg/Na/S/P substrate showed a 70% antithrombotic effect compared to control. Further, alkali treatment enhances the antibacterial characteristic of AZ91 Mg alloy. Also, the alkali‐treated sirolimus‐loaded substrates (Mg/Na/S and Mg/Na/S/P) inhibit the valvular interstitial cell's growth significantly in in‐vitro. Hence, the results imply that sirolimus‐loaded PLGA‐coated AZ91 Mg alloy‐based substrate can be a potential candidate for cardiovascular stent application.