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Background and purpose: Glioma is a common malignant tumor of central nervous system with poor prognosis. Postoperative concurrent chemoradiotherapy with temozolomide (TMZ) is the main treatment for glioma. The methylation status of the O6-methylguanine-DNA methyltransferase (MGMT) promoter can predict the sensitivity of glioma patients to TMZ treatment, however its relationship with clinical pathology and how to better predict treatment and prognosis still need further research. The purpose of this study was to analyze the status of MGMT promoter methylation (MGMTmet) in gliomas and its correlation with clinical pathological features and other common molecular abnormalities, and to explore the value of combined analysis of MGMTmet and other molecular abnormalities in predicting the prognosis of glioma and the efficacy of TMZ treatment. Methods: We retrospectively collected clinical and pathological data from 205 glioma patients diagnosed by the Department of Pathology, Fudan University Shanghai Cancer Center from July 2019 to September 2022. Real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR) was used to detect MGMTmet status. Sanger sequencing was used to detect the mutation of isocitrate dehydrogenase 1 and 2 (IDH1/2) and telomerase reverse transcriptase (TERT) genes. Fluorescence in situ hybridization (FISH) was used to detect the deletion of the short arm of chromosome 1 and the long arm of chromosome 19 (1p19q). Results: Among 205 patients, the incidence of MGMTmet was higher in female patients than in male patients. Compared to glioblastoma (47.3%), astrocytoma (74.1%) and oligodendroglioma (100.0%) were more prone to methylation of the MGMT gene promoter (P

Abstract In some complicated situations, decompression sickness (DCS) combined with other injuries, such as irradiation, will seriously endanger life safety. However, it is still unclear whether irradiation will increase the incidence of DCS. This study was designed to investigate the damage effects of irradiation on decompression injury and the underlying mechanism. Sprague–Dawley rats were exposed to irradiation followed by hyperbaric decompressing and the mortality and decompression symptoms were observed. Lung tissue and bronchoalveolar lavage fluid were collected to detect the lung lesion, inflammation response, activity of the angiotensin system, oxidative stress, and relative signal pathway by multiple methods, including Q-PCR, western blot, and ELISA. As a result, pre-exposure to radiation significantly exacerbated disease outcomes and lung lesions of DCS. Mechanically, the up-regulation of angiotensin-converting enzyme expression and angiotensin II levels was responsible for the exacerbated DCS and lung lesions caused by predisposing irradiation exposure. Oxidative stress and PI3K/AKT signal pathway activation in pulmonary tissue were enhanced after irradiation plus decompression treatment. In conclusion, our results suggested that irradiation could exacerbate lung injury and the outcomes of DCS by activating the angiotensin system, which included eliciting oxidative stress and activation of the PI3K/AKT signal pathway.

Energy circulation in geospace lies at the heart of space weather research. In the inner magnetosphere, the steep plasmapause boundary separates the cold dense plasmasphere, which corotates with the planet, from the hot ring current/plasma sheet outside. Theoretical studies suggested that plasmapause surface waves related to the sharp inhomogeneity exist and act as a source of geomagnetic pulsations, but direct evidence of the waves and their role in magnetospheric dynamics have not yet been detected. Here, we show direct observations of a plasmapause surface wave and its impacts during a geomagnetic storm using multi-satellite and ground-based measurements. The wave oscillates the plasmapause in the afternoon-dusk sector, triggers sawtooth auroral displays, and drives outward-propagating ultra-low frequency waves. We also show that the surface-wave-driven sawtooth auroras occurred in more than 90% of geomagnetic storms during 2014-2018, indicating that they are a systematic and crucial process in driving space energy dissipation.

The accurate segmentation of liquid drop image is an important part of high precision contact Angle measurement.Aiming at the problems of inaccurate target, incomplete contour, and poor effect of solid-liquid-vapor intersection and boundary details in the process of liquid drop segmentation, a neural network model suitable for liquid drop segmentation is proposed.The model is based on U-Net network, and a 1×1 convolution layer is added at its input to summarize image features to avoid losing information from the initial image.Resnet18 structure is used as the feature learning encoder of U-Net to enhance the expression ability of the network and promote the propagation of gradient.The feature fusion technology of dense connection is added in the decoding process, which improves the detail information of segmented target and reduces the network parameters.Finally, a batch normalization operation is added after each convolution layer to further optimize the network performance.Experimental results show that the improved U-Net model can effectively improve the accuracy of droplet identification and segmentation effect, and has a certain reference value in the field of contact Angle measurement.

[INLINE:1] The introduction of neurotrophic factors into injured peripheral nerve sites is beneficial to peripheral nerve regeneration. However, neurotrophic factors are rapidly degraded in vivo and obstruct axonal regeneration when used at a supraphysiological dose, which limits their clinical benefits. Bioactive mimetic peptides have been developed to be used in place of neurotrophic factors because they have a similar mode of action to the original growth factors and can activate the equivalent receptors but have simplified sequences and structures. In this study, we created polydopamine-modified chitin conduits loaded with brain-derived neurotrophic factor mimetic peptides and vascular endothelial growth factor mimetic peptides (Chi/PDA-Ps). We found that the Chi/PDA-Ps conduits were less cytotoxic in vitro than chitin conduits alone and provided sustained release of functional peptides. In this study, we evaluated the biocompatibility of the Chi/PDA-Ps conduits. Brain-derived neurotrophic factor mimetic peptide and vascular endothelial growth factor mimetic peptide synergistically promoted proliferation of Schwann cells and secretion of neurotrophic factors by Schwann cells and attachment and migration of endothelial cells in vitro. The Chi/PDA-Ps conduits were used to bridge a 2 mm gap between the nerve stumps in rat models of sciatic nerve injury. We found that the application of Chi/PDA-Ps conduits could improve the motor function of rats and reduce gastrocnemius atrophy. The electrophysiological results and the microstructure of regenerative nerves showed that the nerve conduction function and remyelination was further restored. These findings suggest that the Chi/PDA-Ps conduits have great potential in peripheral nerve injury repair.