Thermal damage and the prognostic evaluation of laser ablation of bone tissue-a review.

In recent years, an increasing number of scientists have focused on conducting experiments on laser ablation of bone tissue. The purpose of this study was to summarize the prognosis of tissue and the extent of thermal damage in past hard tissue ablation experiments, and review the evidence for the feasibility of laser osteotomy in surgery. An electronic search of PubMed, China National Knowledge Infrastructure (CNKI), and Web of Science (WOS) for relevant English-language articles published through June 2023 was conducted. This review includes 48 literature reports on laser ablation of hard tissues from medical and biological perspectives. It summarizes previous studies in which the ideal ablation rate, depth of ablation, and minimal damage to bone tissue and surrounding soft tissues were achieved by changing the laser type, optimizing the laser parameter settings, or adding adjuvant devices. By observing their post-operative healing and inflammatory response, this review aims to provide a better understanding of pulsed laser ablation of hard tissues. Previous studies suggest that laser osteotomy has yielded encouraging results in bone resection procedures. We believe that low or even no thermal damage can be achieved by experimentally selecting a suitable laser type, optimizing laser parameters such as pulse duration and frequency, or adding additional auxiliary cooling devices. However, the lack of clinical studies makes it difficult to conclusively determine whether laser osteotomy is superior in clinical applications.

Natural products: protective effects against ischemia-induced retinal injury.

Ischemic retinal damage, a common condition associated with retinal vascular occlusion, glaucoma, diabetic retinopathy, and other eye diseases, threatens the vision of millions of people worldwide. It triggers excessive inflammation, oxidative stress, apoptosis, and vascular dysfunction, leading to the loss and death of retinal ganglion cells. Unfortunately, minority drugs are available for treating retinal ischemic injury diseases, and their safety are limited. Therefore, there is an urgent need to develop more effective treatments for ischemic retinal damage. Natural compounds have been reported to have antioxidant, anti-inflammatory, and antiapoptotic properties that can be used to treat ischemic retinal damage. In addition, many natural compounds have been shown to exhibit biological functions and pharmacological properties relevant to the treatment of cellular and tissue damage. This article reviews the neuroprotective mechanisms of natural compounds involve treating ischemic retinal injury. These natural compounds may serve as treatments for ischemia-induced retinal diseases.

Progress on Brain and Ocular Lymphatic System.

In recent years, 2 major discoveries have modified the traditional understanding of the brain. First, meningeal lymphatic vessels (MLV) were found in the dural sinus, which may absorb and drain cerebrospinal fluid (CSF). Second, the glymphatic system was discovered, composed of para-arterial CSF influx channel, paravenous interstitial fluid (ISF) efflux channel, and the water channel aquaporin-4 (AQP4) in astrocytes connecting the 2 channels. Accumulating evidence demonstrates that the lymphatic system of the brain plays a vital role within the circulation of CSF and, therefore, in the removal of metabolites. Therefore, it is involved in the incidence and development of some central nervous system (CNS) diseases. The optic nerve and retina are the extension of the CNS in the orbit. Whether they have a lymphatic system and how they clear the metabolites of the optic nerve and retina are still unclear. Recent studies have found that the ocular lymphatic system has a crucial impact on bounding eye diseases, like disorders of the optic nerve and retina. Therefore, here we review the recent research progress concerning the structure and function of MLV and glymphatic system. We also discuss the biomarkers for identification of lymphatic vessels, the composition of ocular lymphatic systems, and the possible association with diseases.

The Role of Nanotechnology in Subgrade and Pavement Engineering: A Review.

Nanotechnology is an extension of sciences and technologies that deal with particles less than 100 nm. This paper reviews previous studies on how nanomaterials work and what their advantages are in subgrade and pavement engineering. In subgrade engineering, the nanomaterials particles can not only improve the physicochemical and mechanical properties of subgrade soils by filling the voids between soil particles but also promote hydration reaction between cement and ion exchange between soil particles. In pavement engineering, the water stability, rutting resistance, fatigue resistance and optical properties of flexible pavements are enhanced by adding nanomaterials into the asphalt mixture. Nanosilica enhances the interface between cement pastes and aggregates and promotes the pozzolanic reaction of concrete, thus, mechanical properties of concrete pavements are improved. Compared with traditional materials, nanomaterials play a promising role in subgrade and pavement engineering, benefitting from their environmental friendliness, lower environmental disturbance, better price/performance ratio and higher durability.