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As the SARS-CoV-2 coronavirus continues to evolve and infect the global population, many individuals are likely to suffer from post-acute sequelae of SARS-CoV-2 infection (PASC). Manifestations of PASC include vision symptoms, but little is known about the ability of SARS-CoV-2 to infect and impact the retinal cells. Here, we demonstrate that SARS-CoV-2 can infect and perturb the retinal pigment epithelium (RPE) in vivo, after intranasal inoculation of a transgenic mouse model of SARS-CoV-2 infection, and in cell culture. Separate lentiviral studies showed that SARS-CoV-2 Spike protein mediates viral entry and replication in RPE cells, while the Envelope and ORF3a proteins induce morphological changes. Infection with major variants of SARS-CoV-2 compromised the RPE barrier function and phagocytic capacity. It also caused complement activation and production of cytokines and chemokines, resulting in an inflammatory response that spread across the RPE layer. This inflammatory signature has similarities to that associated with the onset of age-related macular degeneration (AMD), a major cause of human blindness, resulting from RPE pathology that eventually leads to photoreceptor cell loss. Thus, our findings suggest that post-acute sequelae of SARS-CoV-2 infection of the RPE may have long-term implications for vision, perhaps comparable to the increased occurrence of AMD found among individuals infected by HIV, but with greater public health consequences due to the much larger number of SARS-CoV-2 infections., (© The Author(s) 2024. Published by Oxford University Press on behalf of National Academy of Sciences.)

Background: Developmental dysplasia of the hip (DDH) is a common pediatric orthopedic condition characterized by varying degrees of acetabular dysplasia and hip dislocation. Current 2D imaging methods often fail to provide sufficient anatomical detail for effective treatment planning, leading to higher rates of misdiagnosis and missed diagnoses. MRI, with its advantages of being radiation-free, multi-planar, and containing more anatomical information, can provide the crucial morphological and volumetric data needed to evaluate DDH. However, manual techniques for measuring parameters like the center-edge angle (CEA) and acetabular index (AI) are time-consuming. Automating these processes is essential for accurate clinical assessments and personalized treatment strategies., Methods: This study employed a U-Net-based CNN model to automate the segmentation of hip MRI images in children. The segmentation process was validated using a leave-one-out method during training. Subsequently, the segmented hip joint images were utilized in clinical settings to perform automated measurements of key angles: AI, femoral neck angle (FNA), and CEA. This automated approach aimed to replace manual measurements and provide an objective reference for clinical assessments., Results: The U-Net-based network demonstrates high effectiveness in hip segmentation compared to manual radiologist segmentations. In test data, it achieves average DSC values of 0.9109 (acetabulum) and 0.9244 (proximal femur), with a 91.76% segmentation success rate. The average ASD values are 0.3160 mm (acetabulum) and 0.6395 mm (proximal femur) in test data, with Ground Truth (GT) edge points and predicted segmentation maps having a mean distance of less than 1 mm. Using automated segmentation models for clinical hip angle measurements (CEA, AI, FNA) shows no statistical difference compared to manual measurements (p > 0.05)., Conclusion: Utilizing U-Net-based image segmentation and automated measurement of morphological parameters significantly enhances the accuracy and efficiency of DDH assessment. These methods improve precision in automatic measurements and provide an objective basis for clinical diagnosis and treatment of DDH., (© 2024. The Author(s).)

Mitochondria are dynamic organelles that alter their morphological characteristics in response to functional needs. Therefore, mitochondrial morphology is an important indicator of mitochondrial function and cellular health. Reliable segmentation of mitochondrial networks in microscopy images is a crucial initial step for further quantitative evaluation of their morphology. However, 3D mitochondrial segmentation, especially in cells with complex network morphology, such as in highly polarized cells, remains challenging. To improve the quality of 3D segmentation of mitochondria in super-resolution microscopy images, we took a machine learning approach, using 3D Trainable Weka, an ImageJ plugin. We demonstrated that, compared with other commonly used methods, our approach segmented mitochondrial networks effectively, with improved accuracy in different polarized epithelial cell models, including differentiated human retinal pigment epithelial (RPE) cells. Furthermore, using several tools for quantitative analysis following segmentation, we revealed mitochondrial fragmentation in bafilomycin-treated RPE cells., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Vegetation concrete has been widely applied for the ecological restoration of bare steep slopes in short-term frozen and non-frozen soil regions in China. However, field experiments conducted in seasonally frozen soil regions have revealed decreases in the bulk density, nutrient content and vegetation coverage. This study aimed to clarify the evolution process and mechanism of the engineering properties of vegetation concrete under atmospheric freeze-thaw (F-T) test conditions. The physical, mechanical, and nutrient properties of vegetation concrete were investigated using six F-T cycles (0, 1, 2, 5, 10 and 20) and two initial soil water contents (18 and 22%). The results revealed decreases in the acoustic wave velocity and cohesive forces and an increase in the permeability coefficient of the vegetation concrete owing to F-T action. X-ray diffraction tests indicated that the decreased cohesive force was closely related to the overall decrease in the content of gelling hydration products in the vegetation concrete. Additionally, the contents of NH 4 + -N, PO 4 3 -P and K + in the vegetation concrete increased, whereas that of NO 3 - -N decreased. The loss rates of these soluble nutrients increased, indicating that the nutrient retention capacity of the vegetation concrete had decreased. Specifically, the decreased nutrient retention capacity was mainly related to the disintegration and fragmentation of larger aggregates due to F-T action. This study provides theoretical support for future research on improving the anti-freezing capability of ecological slope protection substrates in seasonally frozen soil regions., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

4-(2-Butyl-6,7-dichloro-2-cyclopentyl-indan-1-on-5-yl) oxobutyric acid (DCPIB), was discovered to be a potent and specific antagonist of volume-regulated anion channel that is closely linked to angiogenesis. However, the effect of DCPIB on angiogenesis remains unclear. Here, we found that DCPIB inhibited angiogenesis in the corneal suture and myocardial infarction in vivo model. In addition, DCPIB inhibited human umbilical vein endothelial cell migration, tube formation and proliferation in vitro . Moreover, DCPIB repressed the activation and expression of vascular endothelial growth factor receptor 2 (VEGFR2) and its downstream signaling pathway. Computer modeling further confirmed that DCPIB binds with high affinity to VEGFR2. Collectively, we present evidence supporting an antiangiogenic role of DCPIB by targeting VEGFR2 signaling pathway, which suggests that DCPIB is a valuable lead compound for the treatment of angiogenesis-related diseases., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhou, Li, Zhang, Pan, Pang, Yuan, Li, Jie, Wang and Zhang.)

Objective: To investigate the variation in T2 at different zones of normal hip cartilage in children and the relationship between T2 value and age., Materials and Methods: Nineteen children with 30 normal hip joints were evaluated with a coronal T2 mapping sequence at a 3-Tesla MRI system. The femoral cartilage and acetabular cartilage were firstly segmented by mask-based interactive method and then equally divided into eight and six radial sections, respectively. Moreover, each radial section was further divided into two layers referring to the superficial and deep halves of the corresponding cartilage. Cartilage T2 of these sections and layers were measured and subsequently analyzed., Results: There was a negative correlation between the T2 values in the hip cartilage and the age of children (r s < - 0.6, P1 < 0.05). Articular cartilage T2 increased at angles close to the magic angle (54.7°). Femoral cartilage and acetabular cartilage had a relatively shorter T2 in the radial sections near the vertex of the femoral head. The T2 values in superficial layers of both cartilages were significantly higher than those in deep layers (P < 0.05)., Conclusion: The T2 value decreases as the cartilage developing into a more mature state. Cartilage T2 values in the weight-bearing areas are relatively low due to an increase of collagen density and the loss of interstitial water. The restriction of the water molecules by solid components in the deeper layer of cartilage may decrease the T2 values., (© 2021. European Society for Magnetic Resonance in Medicine and Biology (ESMRMB).)

A simple and efficient strategy that takes advantages of the synergistic effect of microwave heating method and hydrothermal method is used to synthesize Ni 2 CoS 4 /graphene oxide (MH-Ni 2 CoS 4 /GO). Firstly, Ni 2 CoS 4 nanoparticles are observed to grow uniformly on the surface of GO. Then the obtained MH-Ni 2 CoS 4 /GO electrode is tested and it demonstrates ultrahigh specific capacitance of 2675.0 F g -1 at the current densities of 2 A g -1 , fantastic stability of 95.0% even after 2000 cycles at 30 A g -1 and excellent rate capability of 89.7% with current density increasing from 2 A g -1 to 30 A g -1 . Moreover, the assembled AC//MH-Ni 2 CoS 4 /GO asymmetric supercapacitor also delivers a good specific capacitance of 126.5 F g -1 at 0.5 A g -1 , outstanding stability of 97.0% after 2000 cycles at 5.0 A g -1 , and an ultrahigh energy density of 59.6 Wh kg -1 at power density of 497.6 W kg -1 . This work provides an approach to synthesize electrode materials with superior excellent performances and it can be easily scaled up for practical applications in supercapacitors., Competing Interests: Declaration of Competing Interest No conflict of interest exits and the manuscript is approved by all authors for publication. I would like to declare on behalf of my co-authors that the work was original research that has not been published previously, and no consideration for publication elsewhere, in whole or in part., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Ticks are known as the vectors of various zoonotic diseases such as Lyme borreliosis and tick-borne encephalitis. Though their occurrences are increasingly reported in some parts of China, our understanding of the pattern and determinants of ticks' potential distribution over the country remain limited. In this study, we took advantage of the recently compiled spatial dataset of distribution and diversity of ticks in China, analyzed the environmental determinants of ten frequently reported tick species and mapped the spatial distribution of these species over the country using the MaxEnt model. We found that presence of urban fabric, cropland, and forest in a place are key determents of tick occurrence, suggesting ticks were likely inhabited close to where people live. Besides, precipitation in the driest month was found to have a relatively high contribution in mapping tick distribution. The model projected that theses ticks could be widely distributed in the Northwest, Central North, Northeast, and South China. Our results added new evidence on the potential distribution of a variety of major tick species in China and pinpointed areas with a high potential risk of tick bites and tick-borne diseases for raising public health awareness and prevention responses.

Limited by the chemical inertness of CO 2 and the high dissociation energy of the C═O bond, photocatalytic CO 2 conversion is highly challenging. Herein, we prepare ultrathin oxygen-modified h-BN (O/BN) nanosheets containing B-O bonds. On the O/BN surface, CO 2 can be chemically captured and is bonded with the B-O bond, leading to the formation of an O-B-O bond. This new chemical bond acting as an electron-delivery channel strengthens the interaction between CO 2 and the surface. Thus, the reactants can continuously obtain electrons from the surface through this channel. Therefore, the majority of gaseous CO 2 directly converts into carbon active species that are detected by in situ DRIFTS over O/BN. Moreover, the activated energies of CO 2 conversion are significantly reduced with the introduction of the B-O bond evidenced by DFT calculations. As a result, O/BN nanosheets present an enhanced photocatalytic CO 2 conversion performance with the H 2 and CO generation rates of 3.3 and 12.5 μmol g -1 h -1 , respectively. This work could help in realizing the effects of nonmetal chemical bonds in the CO 2 photoreduction reaction for designing efficient photocatalysts.