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Osteoarthritis (OA) is recognized as a highly friction‐related joint disease primarily associated with increased joint friction and inflammation due to pro‐inflammatory M1‐type macrophage infiltration in the articular cavity. Therefore, strategies to simultaneously increase lubrication and relieve inflammation to remodel the damaged articular microenvironment are of great significance for enhancing its treatment. Herein, a multifunctional core‐brush nanoplatform composed of a ROS‐scavenging polydopamine‐coated SiO2 core and lubrication‐enhancing zwitterionic poly(2‐methacryloyloxyethyl phosphorylcholine) (PMPC) brush and loaded with the anti‐inflammatory drug curcumin by a reactive oxygen species (ROS)‐liable conjugation (named as SiO2@PP‐Cur) is rationally designed. Benefiting from the grafted zwitterionic PMPC brush, a tenacious hydration layer with enhanced lubricity for reducing joint abrasions is developed. More importantly, based on the mono‐iodoacetic acid‐induced arthritis (MIA) rat model, intra‐articular injection of SiO2@PP‐Cur nanoplatform can effectively alleviate articular inflammation via promoting macrophage polarization from the pro‐inflammatory M1 to anti‐inflammatory M2 state by activating the nuclear factor erythroid 2‐related factor 2 (Nrf2) signaling pathway and attenuating the degradation of cartilage matrix, resulting in the remodeling of the damaged microenvironment into a pro‐regenerative microenvironment. As a result, SiO2@PP‐Cur can considerably inhibit OA progression. Therefore, the work may provide a novel strategy for the development of an advanced core‐brush nanoplatform for enhanced OA therapy. [ABSTRACT FROM AUTHOR]

Three-dimensional surfaces are typically modeled as implicit surfaces. However, direct rendering of implicit surfaces is not simple, especially when such surfaces contain finely detailed shapes. One approach is ray-casting, where the field of the implicit surface is assumed to be piecewise polynomials defined on the grid of a rectangular domain. A critical issue for direct rendering based on ray-casting is the computational cost of finding intersections between surfaces and rays. In particular, ray-casting requires many function evaluations along each ray, severely slowing the rendering speed. In this paper, a method is proposed to achieve direct rendering of polynomial-based implicit surfaces in real-time by strategically narrowing the search range and designing the shader to exploit the structure of piecewise polynomials. In experiments, the proposed method achieved a high framerate performance for different test cases, with a speed-up factor ranging from 1.1 to 218.2. In addition, the proposed method demonstrated better efficiency with high cell resolution. In terms of memory consumption, the proposed method saved between 90.94% and 99.64% in different test cases. Generally, the proposed method became more memory-efficient as the cell resolution increased. [ABSTRACT FROM AUTHOR]

Blood brain barrier (BBB) protects homeostasis and sensitive environment of brain from several toxic substances coming from the systemic circulation. This barrier along with those substances also prevents therapeutic chemicals to reach brain tissues for several brain diseases. BBB consists of a number of cell types and junctions that help maintain its intricate structure and physiology. To open BBB for therapeutic purposes, researchers are keen to explore the use of nanomaterials as therapeutic agents. Nanomaterials have unique physio‐chemical properties such as, increased surface area to mass ratio, superior adsorption capacity, and a wide variety of functionalization possibilities in contrast to bulk materials, making them sought‐after for research pertaining to brain delivery of therapeutic substances. Both organic and inorganic nanomaterials have been researched in this regard with numerous interesting functionalizations, and their toxicity and distribution profiles have been well assessed. Different pathways taken up by nanomaterials to cross BBB like adsorptive‐mediated transcytosis, inhibition of active efflux pumps, receptor‐mediated transport, and cell‐mediated endocytosis have also been investigated. This review summarizes the structural and physiological properties and the modulation techniques of BBB for delivery of adsorbed/functionalized nano delivery platforms and imaging nanomaterials across. [ABSTRACT FROM AUTHOR]