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Aim: The aim of this present study was to investigate the antifungal mechanism of sertraline against Candida auris (C. auris) and its effect on biofilm formation. Methods and Results: Sertraline, a repurposing drug with a history of human use for the treatment of depression was screened against three different isolates of C. auris, and was found to possess efficient antifungal activity. The antifungal activity of sertraline was further confirmed by killing kinetics assay and post‐antifungal effect (PAFE). Sertraline inhibited C. auris yeast to hyphae conversion and further the inhibition of biofilm formation showed 71% inhibition upon treatment. Cell damage caused due to C. auris after treatment with sertraline was observed using SEM and cell membrane damage was ascertained using flow cytometry by Propidium Iodide (PI) uptake assay. The results of sorbitol protection assay and ergosterol effect assay suggested that sertraline did not affect the cell wall and did not act by binding to membrane ergosterol. The mechanism of action of sertraline against C. auris was understood through in silico docking studies that revealed the binding nature of sertraline to the sterol 14 alpha demethylase which is involved in ergosterol biosynthesis. Ergosterol that was quantified from treated cells showed a 5·5‐fold decrease in ergosterol production. Conclusion: Sertraline displayed promising antifungal activity against C. auris involved in candidiasis infection and the mechanism of action was predicted. Significance and impact of this study: The results of this study can encourage for the development of new antifungal agents and can be promising antifungal agent against C. auris infection. [ABSTRACT FROM AUTHOR]

Abstract: Hydroxyapatite (HA) resembles natural bone mineral in its major composition and is widely applied for various biomedical applications in different forms. Wet chemical precipitation is an economic and simple route to synthesize HA. But the thermal stability and other related properties of synthesized HA depend on various factors. Here we demonstrate that when ultrasonication is coupled with synthesis and specimen is dried via sublimation (freeze drying) instead of the conventional hot air drying the thermal stability, densification and sinterability are improved. [Copyright &y& Elsevier]

Abstract: Ascorbic acid (AA—Vitamin C) plays a vital role in human body to preserve optimal health. However, high intake may cause the formation of pathological calcium oxalate stones. Calcium oxalate and calcium phosphates are the major crystalline constituents of the urinary calculi and commonly found together. The effect of AA on the crystallization of calcium phosphate was studied in gel matrix under physiological conditions. Calcium phosphates such as hydroxyapatite (HAp), brushite (DCPD) and calcium oxalate dihydrate (COD—Weddellite) were found to crystallize simultaneously in the gel matrix. The formation of HAp is accelerated by AA. A possible reaction scheme for the formation of COD by the metal induced conversion of AA is proposed. [Copyright &y& Elsevier]

Both strontium and ciprofloxacin are known to be functional materials for the treatment of bone diseases associated to the loss of bone substance. In this work we prepared the strontium (Sr) modified hydroxyapatite (SrHA) and ciprofloxacin (Cip) modified SrHA bone substitutes by one pot facile chemical precipitation route. The calcium release is improved more for SrHA compared with stoichiometric HA owing to the higher solubility of the Sr. Drug release profile exhibited the sustained and prolonged release of Cip up to 45 days. The in-vitro cell responses showed that the Sr addition improved the ALP activity of the osteoblast like MG-63 cells which confirms the enhanced cell viability and functionality of the strontium modified hydroxyapatite ceramics. [ABSTRACT FROM AUTHOR]

Abstract: The effect of swift heavy ion irradiation on hydroxyapatite (HAp) ceramic – a bone mineral was investigated. The irradiation experiment was conducted using oxygen ions at energy of 100MeV with three different fluences of 1012, 1013, 1014 ions/cm2. The irradiated samples were characterized by glancing angle X-ray diffraction (GXRD), atomic force microscopy (AFM), dynamic light scattering (DLS), photoluminescence spectroscopy (PL), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). GXRD confirmed incomplete amorphisation of HAp with increase in fluence. There was considerable reduction in particle size on irradiation leading to nanosized HAp (upto 53nm). PL studies showed emission in the visible wavelength region. The irradiated samples exhibited better bioactivity than the pristine HAp. [Copyright &y& Elsevier]

Abstract: The effect of strontium on the crystallization of helical ribbon of hydroxyapatite (HAp) was investigated by single diffusion technique in silica gel matrix at 27°C and physiological pH. Fibers of HAp were obtained on addition of strontium. The length of the HAp fibers, were found to decrease as the strontium substitution increases. The presence of strontium ion increased the crystallinity as well as crystallite size of HAp. The strontium substituted HAp (Sr-HAp) has similar stoichiometry to that of biological apatite. Sr-HAp was found to have increased surface area (35%) compared to control. Further, strontium substitution leads to an enhancement of in vitro bioactivity. The cumulative in-vitro amoxicillin drug release in phosphate buffer solution (PBS, pH 7.2) showed a prolonged release profile for Sr-HAp. [Copyright &y& Elsevier]