Current hyaluronic acid‐based hydrogels often cause cytotoxicity to encapsulated cells and lack the adhesive property required for effective biomedical and tissue engineering applications. Provision of the cell‐adhesive surface is an important requirement to improve its biocompatibility. An aqueous solution of hyaluronic acid possessing phenolic hydroxyl (HA‐Ph) moieties is gellable via a horseradish peroxidase (HRP)‐catalyzed oxidative cross‐linking reaction. This study evaluates the effect of different degrees of cross‐linked Ph moieties on cellular adhesiveness and proliferation on the resultant enzymatically cross‐linked HA‐Ph hydrogels. Mechanical characterization demonstrated that the compression force of engineered hydrogels could be tuned in the range of 0.05–35 N by changing conjugated Ph moieties in the precursor formulation. The water contact angle and water content show hydrophobicity of hydrogels increased with increasing content of cross‐linked Ph groups. The seeded mouse embryo fibroblast‐like cell line and human cervical cancer cell line, on the HA‐Ph hydrogel, proved cell attachment and spreading with a high content of cross‐linked Ph groups. The HA‐Ph with a higher degree of Ph moieties shows the maximum degree of cell adhesion, spreading, and proliferation which presents this hydrogel as a suitable biomaterial for biomedical and tissue engineering applications.

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Gold nanoparticles with suitable properties are supreme therapeutic agents and provide effective signal enhancement in photodynamic therapy (PDT).

Neuropsychiatric disorders, such as addiction, are associated with cognitive impairment, including learning and memory deficits. Previous research has demonstrated that the chronic use of methamphetamine (METH) induces long-term cognitive impairment and cannabidiol (CBD), as a neuroprotectant, can reverse spatial memory deficits induced by drug abuse. The study aimed to evaluate the effect of CBD on METH-induced memory impairment in rats chronically exposed to METH (CEM). For the induction of CEM, animals received METH (2 mg/kg, twice/day) for 10 days. Thereafter, the effect of intracerebroventricular (ICV) administration of CBD (32 and 160 nmol) during the (10 days) abstinence period on spatial memory was evaluated using the Y-Maze test, while recognition memory was examined using the novel object recognition (NOR) test. The results revealed a significant increase in the motor activity of METH-treated animals compared with the control group and, after the 10-day abstinence period, motor activity returned to baseline. Notably, the chronic administration of METH had impairing effects on spontaneous alternation performance and recognition memory, which was clearly observed in the NOR test. Additionally, although the ICV administration of CBD (160 nmol) could reverse long-term memory, a lower dose (32 nmol) did not result in any significant increase in exploring the novel object during short-term memory testing. These novel findings suggest that the chronic administration of METH induces memory impairment and presents interesting implications for the potential use of CBD in treating impairment deficits after chronic exposure to psychostimulant drugs such as METH.