Laquinimod Inhibits Microglial Activation, Astrogliosis, BBB Damage, and Infarction and Improves Neurological Damage after Ischemic Stroke.

Glial activation is involved in neuroinflammation and blood-brain barrier (BBB) damage, which plays a key role in ischemic stroke-induced neuronal damage; therefore, regulating glial activation is an important way to inhibit ischemic brain injury. Effects of laquinimod (LAQ) include inhibiting axonal damage and neuroinflammation in multiple neuronal injury diseases. However, whether laquinimod can exert neuroprotective effects after ischemic stroke remains unknown. In this study, we investigated the effect of LAQ on glial activation, BBB damage, and neuronal damage in an ischemic stroke model. Adult ICR mice were used to create a photothrombotic stroke (PT) model. LAQ was administered orally at 30 min after ischemic injury. Neurobehavioral tests, Evans Blue, immunofluorescence, TUNEL, Nissl staining, and western blot were performed to evaluate the neurofunctional outcome. Quantification of immunofluorescence was evaluated by unbiased stereology. LAQ post-treatment significantly reduced infarction and improved forepaw function at 5 days after PT. Interestingly, LAQ treatment significantly promoted anti-inflammatory microglial activation. Moreover, LAQ treatment reduced astrocyte activation, glial scar formation, and BBB breakdown in ischemic brains. Therefore, this study demonstrated that LAQ post-treatment restricted microglial polarization, astrogliosis, and glial scar and improved BBB damage and behavioral function. LAQ may serve as a novel target to develop new therapeutic agents for ischemic stroke.

Effect of zirconia surface modification using dopamine polymerisation on the shear bond strength of resin cement.

This study evaluated the influence of polydopamine treatment on the surface properties and bond strength of yttria-stabilised tetragonal zirconia polycrystal (Y-TZP). Sixty-three zirconia blocks (10 × 10 × 2 mm) were randomly divided into three groups defined by surface treatment: (i) control group (C), (ii) grit-blasted with 110 µm alumina particles (GB), and (iii) polydopamine (PDA) coating. The surfaces of specimens subjected to different treatments were investigated by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and water contact angle measurements. After the surface treatments, the specimens were cemented to resin composite cylinders. After bonding, the shear bond strength of the ceramic to the resin was measured, and the failure mode of each specimen was analysed using a stereomicroscope. The results indicated that the shear bond strength is highest for the GB treatment and lowest for the controls. However, the difference between groups GB and PDA was not statistically significant. In the control group, adhesive failure was predominant, whereas in the treatment groups, mixed mode failure was predominant. The pre-treatment of Y-TZP ceramic with the polydopamine coating might improve the bond strength of the resin cement to the zirconia ceramic.