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Disuse osteoporosis (OP) is a state of bone loss due to lack of mechanical stimuli, probably induced by prolonged bed rest, neurological diseases, as well as microgravity. Currently the precise treatment strategies of disuse OP remain largely unexplored. Piezo1, a mechanosensitive calcium (Ca2+) ion channel, is a key force sensor mediating mechanotransduction and it is demonstrated to regulate bone homeostasis and osteogenesis in response to mechanical forces. Using structure‐based drug design, a novel small‐molecule Piezo1 agonist, MCB‐22‐174, which can effectively activate Piezo1 and initiate Ca2+ influx, is developed and is more potent than the canonical Piezo1 agonist, Yoda1. Moreover, MCB‐22‐174 is found as a safe Piezo1 agonist without any signs of serious toxicity. Mechanistically, Piezo1 activation promotes the proliferation of bone marrow mesenchymal stem cells by activating the Ca2+‐related extracellular signal‐related kinases and calcium–calmodulin (CaM)‐dependent protein kinase II (CaMKII) pathway. Importantly, MCB‐22‐174 could effectively promote osteogenesis and attenuate disuse OP in vivo. Overall, the findings provide a promising therapeutic strategy for disuse OP by chemical activation of Piezo1. [ABSTRACT FROM AUTHOR]

In recent years, as the aging population continues to grow, osteoarthritis (OA) has emerged as a leading cause of disability, with its incidence rising annually. Current treatments of OA include exercise and medications in the early stages and total joint replacement in the late stages. These approaches only relieve pain and reduce inflammation; however, they have significant side effects and high costs. Therefore, there is an urgent need to identify effective treatment methods that can delay the pathological progression of this condition. The changes in the articular cartilage microenvironment, which are complex and diverse, can aggravate the pathological progression into a vicious cycle, inhibiting the repair and regeneration of articular cartilage. Understanding these intricate changes in the microenvironment is crucial for devising effective treatment modalities. By searching relevant research articles and clinical trials in PubMed according to the keywords of articular cartilage, microenvironment, OA, mechanical force, hypoxia, cytokine, and cell senescence. This study first summarizes the factors affecting articular cartilage regeneration, then proposes corresponding treatment strategies, and finally points out the future research direction. We find that regulating the opening of mechanosensitive ion channels, regulating the expression of HIF‐1, delivering growth factors, and clearing senescent cells can promote the formation of articular cartilage regeneration microenvironment. This study provides a new idea for the treatment of OA in the future, which can promote the regeneration of articular cartilage through the regulation of the microenvironment so as to achieve the purpose of treating OA. [ABSTRACT FROM AUTHOR]

Introduction: Intracranial branch atheromatous disease (BAD) has been applied to occlusions that occur at the origin of large caliber penetrating arteries due to the microatheromas or large parent artery plaques. This study aimed to explore the association between culprit plaques of large parent arteries, neuroimaging markers of cerebral small vessel disease (CSVD), and the risk of early neurological deterioration (END) in stroke patients with BAD. Methods: A total of 97 stroke patients with BAD in the vascular territories of the lenticulostriate arteries or paramedian pontine arteries, diagnosed using high-resolution magnetic resonance imaging, were prospectively recruited in this observational study. A culprit plaque in the middle cerebral artery was defined as the only arterial plaque on the ipsilateral side of an infarction visible on diffusion-weighted imaging. A culprit plaque in the basilar artery (BA) was identified when it was observed within the same axial slices of an infarction or on the adjacent upper or lower slice, whereas a plaque within the BA located in the ventral region was considered non-culprit. If more than one plaque was present in the same vascular territory, the most stenotic plaque was chosen for the analysis. Four CSVD neuroimaging markers, including white matter hyperintensity, lacunes, microbleeds, and enlarged perivascular spaces, were evaluated in accordance with the total CSVD score. The associations between neuroimaging features of lesions within large parent arteries, neuroimaging markers of CSVD, and the risk of END in stroke patients with BAD were investigated using logistic regression analysis. Results: END occurred in 41 stroke patients (42.27%) with BAD. The degree of large parent artery stenosis (p < 0.001), culprit plaques of large parent arteries (p < 0.001), and plaque burden (p < 0.001) were significantly different between the END and non-END groups in stroke patients with BAD. In logistic regression analysis, culprit plaques of large parent arteries (odds ratio, 32.258; 95% confidence interval, 4.140–251.346) were independently associated with the risk of END in stroke patients with BAD. Conclusions: Culprit plaques of large parent arteries could predict the risk of END in stroke patients with BAD. These results suggest that lesions in the large parent arteries, rather than damage to the cerebral small vessels, contribute to END in stroke patients with BAD. [ABSTRACT FROM AUTHOR]

To address the problems that the UAV (Unmanned Aerial Vehicle) is vulnerable to distance limitation and environmental interference when tracking and landing on a moving platform autonomously, the accuracy of position estimation relying only on visual odometry in the point‐featureless environment is insufficient, and the traditional linear path planning solvers and controllers cannot meet the fast and safe requirements under the non‐linear strong coupling characteristics of the cooperative landing system, an nonlinear model predictive control (NMPC)‐based multi‐sensor fusion method for autonomous landing of UAVs on motion platforms is proposed. The UAV combines the position information obtained by the RTK‐GPS and the image information obtained by the camera and uses the special identification codes placed in the landing area of the UAV to carry out cooperative planning and navigation while using UKF (Unscented Kalman Filter) to estimate the position of the moving platform and using the interference‐resistant NMPC algorithm to optimise the UAV tracking trajectory based on the precise positioning of the two platforms to achieve the autonomous landing control of the UAV. The simulation and practical experimental results show the feasibility and effectiveness of the proposed algorithm and the autonomous landing control method and provide an effective solution for the autonomous landing of quadrotors on arbitrarily moving platforms. [ABSTRACT FROM AUTHOR]