Development, physicochemical characterization and in-vitro biocompatibility study of dromedary camel dentine derived hydroxyapatite for bone repair.

This study aimed to produce hydroxyapatite from the dentine portion of camel teeth using a defatting and deproteinizing procedure and characterize its physicochemical and biocompatibility properties. Biowaste such as waste camel teeth is a valuable source of hydroxyapatite, the main inorganic constituent of human bone and teeth which is frequently used as bone grafts in the biomedical field. Fourier Transform infrared (FTIR), and micro-Raman spectroscopy confirmed the functional groups as-sociated with hydroxyapatite. X-ray diffraction (XRD) studies showed camel dentine-derived hydroxyapatite (CDHA) corresponded with hydroxyapatite spectra. Scanning electron micros-copy (SEM) demonstrated the presence of dentinal tubules measuring from 1.69-2.91 µm. The inorganic phases of CDHA were primarily constituted of calcium and phosphorus, with trace levels of sodium, magnesium, potassium, and strontium, according to energy dispersive X-ray analysis (EDX) and inductively coupled plasma mass spectrometry (ICP-MS). After 28 days of incubation in simulated body fluid (SBF), the pH of the CDHA scaffold elevated to 9.2. in-vitro biocompatibility studies showed that the CDHA enabled Saos-2 cells to proliferate and express the bone marker osteonectin after 14 days of culture. For applications such as bone augmentation and filling bone gaps, CDHA offers a promising material. However, to evaluate the clinical feasibility of the CDHA, further in-vivo studies are required.

Assessing the therapeutic potential of agomelatine, ramelteon, and melatonin against SARS-CoV-2.

BACKGROUND: The SARS-Cov-2(severe acute respiratory syndrome coronavirus 2) infection affecting human populations worldwide is now a very concerning issue considering the morbidity and mortality rates. Despite several measures followed by the medical fraternity and general public, there is no resolution. Therapeutic measures to tackle the infection have been based on researching new designer drug molecules that could prevent viral entry into the human host. Melatonin has been tried as an adjuvant in the management of COVID 19(coronavirus disease) illness but its specific antiviral role has not been investigated. Objectives: The objectives of the present study were to conduct an in-silico analysis to investigate if melatonin and related drugs namely ramelteon and agomelatine could be used as antiviral agents in SARS-CoV-2 infection based on their binding to the SARS-CoV-2 receptor binding site (RBD) and Angiotensin-converting enzyme 2 (ACE 2). METHODS: For docking studies (Pdb Id 1M0J), the SARS-CoV-2 spike protein receptor-binding domain (RBD) crystal structure which was ACE2 cell receptor bounded was employed. From the PubChem database, the three-dimensional configuration of the ligands melatonin, ramelteon, and agomelatine was retrieved, and conceptual density functional theory (CDFT) was performed to determine molecular descriptors. Charges were added and optimized with the universal force field to prepare the ligands for the process of docking. For facilitation of readability by the AutoDock software conversion to PDBQT(Protein Data Bank, Partial Charge (Q), & Atom Type (T)) format was performed. AutoDock version 4.2.6 docking program and AutoDock Tools (ADT) version 1.5.6 were used for molecular docking. Desmond, a Package of Schrödinger LLC was used to simulate molecular dynamics for hundred nanoseconds using. RESULTS: Data from the present study reveal that melatonin, ramelteon, and agomelatine demonstrate significant binding with SARS-CoV-2 RBD and ACE 2 demonstrating the fact that they can strongly prevent viral entry into the host cells through dual binding effects. However, Ramelteon was found to be the most superior amongst the 3 drugs analyzed in its antiviral properties against SARS-CoV-2. CONCLUSION: Results advocate further research in exploring the potential therapeutic applications of melatonin, ramelteon, and agomelatine for the management of SARS-CoV-2 infection.

Efficacy and Safety of Enoxaparin versus New Oral Anticoagulants to Prevent Venous Thromboembolism after Total Hip Replacement: A Systematic Review and Meta-Analysis.

Prophylactic anticoagulant therapy is recommended for reducing the risk of venous thromboembolism (VTE) after a total hip replacement (THR). However, it is not clear which anticoagulant is preferable. Hence, a systematic review and meta-analysis of randomized double-blind controlled trials (RDBCTs) were conducted to investigate the clinical efficacy and safety of enoxaparin in comparison with newer oral anticoagulants for the prevention of VTE after THR. The Cochrane Library, Scopus, Web of Science, Embase, and PubMed/Medline databases were used for PICO search strategy. Relative risks (RR) of symptomatic VTE, clinically relevant bleeding, mortality, and a net clinical endpoint were estimated employing a random effect meta-analysis. ITC and RevMan software were used for indirect and direct comparisons, respectively. Nine RDBCTs comprising 24,584 patients were included. As compared to enoxaparin, a reduced risk for symptomatic VTE was observed with rivaroxaban (confidence interval [CI]: 0.32-0.77; RR: 0.46%) and comparable with apixaban (0.12-1.26; 0.42%) and dabigatran (0.22-2.20; 0.70%). Contrarily to enoxaparin, a greater risk for clinically relevant bleeding was observed with rivaroxaban (1.03-1.48; 1.23%), comparable with dabigatran (0.96-1.33; 1.10%) and reduced with apixaban (0.19-5.66; 0.96%). In indirect or direct comparisons, the interventions did not differ on the net clinical endpoint. In conclusion, the findings of this meta-analysis revealed no significant difference in the efficacy and safety of new oral anticoagulants as compared to enoxaparin for the prevention of VTE after total hip replacement surgery.