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Fusing object detection techniques and stochastic variational inference, we proposed a new scheme for lightweight neural network models, which could simultaneously reduce model sizes and raise the inference speed. This technique was then applied in fast human posture identification. The integer-arithmetic-only algorithm and the feature pyramid network were adopted to reduce the computational complexity in training and to capture features of small objects, respectively. Features of sequential human motion frames (i.e., the centroid coordinates of bounding boxes) were extracted by the self-attention mechanism. With the techniques of Bayesian neural network and stochastic variational inference, human postures could be promptly classified by fast resolving of the Gaussian mixture model for human posture classification. The model took instant centroid features as inputs and indicated possible human postures in the probabilistic maps. Our model had better overall performance than the baseline model ResNet in mean average precision (32.5 vs. 34.6), inference speed (27 vs. 48 milliseconds), and model size (46.2 vs. 227.8 MB). The model could also alert a suspected human falling event about 0.66 s in advance.
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The main cause of excitotoxic neuronal death in ischemic stroke is the massive release of glutamate. Recently, microRNAs (miRNAs) have been found to play an essential role in stroke pathology, although the molecular mechanisms remain to be investigated. Here, to identify potential candidate miRNAs involved in excitotoxicity, we treated rat primary cortical neurons with glutamate and found that miR-3068-3p, a novel miRNA, was up-regulated. We hypothesized that restoring miR-3068-3p expression might influence the neuronal injury outcomes. The inhibition of miR-3068-3p, using tough decoy lentiviruses, significantly attenuated the effects of glutamate on neuronal viability and intracellular calcium overload. To unravel the mechanisms, we employed bioinformatics analysis and RNA sequencing to identify downstream target genes. Additional luciferase assays and western blots validated kcnip4, a Kv4-mediated A-type potassium current (IA ) regulator, as a direct target of miR-3068-3p. The inhibition of miR-3068-3p increased kcnip4 expression and vice versa. In addition, the knockdown of kcnip4 by shRNA abolished the protective effect of miR-3068-3p, and over-expressing kcnip4 alone was sufficient to play a neuroprotective role in excitotoxicity. Moreover the inhibition of miR-3068-3p enhanced the IA density, and the pharmacological inhibition of IA abrogated the protective role of miR-3068-3p inhibition and kcnip4 over-expression. Therefore, we conclude that inhibition of miR-3068-3p protects against excitotoxicity via its target gene, kcnip4, and kcnip4-regulated IA . Our data suggest that the miR-3068-3p/kcnip4 axis may serve as a novel target for the treatment of ischemic stroke.
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Regulação para Baixo/fisiologia , Ácido Glutâmico/toxicidade , Proteínas Interatuantes com Canais de Kv/metabolismo , MicroRNAs/metabolismo , Neuroproteção/fisiologia , Animais , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Feminino , Células HEK293 , Humanos , MicroRNAs/antagonistas & inibidores , Neuroproteção/efeitos dos fármacos , Gravidez , Ratos , Ratos Sprague-DawleyRESUMO
Plasticity of the axon initial segment (AIS) has aroused great interest in recent years because it regulates action potential initiation and neuronal excitability. AIS plasticity manifests as modulation of ion channels or variation in AIS structure. However, the mechanisms underlying structural plasticity of the AIS are not well understood. Here, we combined immunofluorescence, patch-clamp recordings, and pharmacological methods in cultured hippocampal neurons to investigate the factors participating in AIS structural plasticity during development. With lowered neuronal density, the distance between the AIS and the soma increased, while neuronal excitability decreased, as shown by the increased action potential threshold and current threshold for firing an action potential. This variation in the location of the AIS was associated with cellular secretory substances, including brain-derived neurotrophic factor (BDNF) and neurotrophin 3 (NT3). Indeed, blocking BDNF and NT3 with TrkB-Fc eliminated the effect of conditioned medium collected from high-density cultures on AIS relocation. Elevating the extracellular concentration of BDNF or NT3 promoted movement of the AIS proximally to the soma and increased neuronal excitability. Furthermore, knockdown of neurotrophin receptors TrkB and TrkC caused distal movement of the AIS. Our results demonstrate that BDNF and NT3 regulate AIS location and neuronal excitability. These regulatory functions of neurotrophic factors provide insight into the molecular mechanisms underlying AIS biology.
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Segmento Inicial do Axônio/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/metabolismo , Fatores de Crescimento Neural/metabolismo , Neurotrofina 3/metabolismo , Potenciais de Ação/fisiologia , Animais , Células Cultivadas , Hipocampo/efeitos dos fármacos , Ratos Sprague-DawleyRESUMO
Gobio huanghensis, a member of the eponymous genus within the Cyprinidae, family of the Cypriniformes order, is an endemic fish species found exclusively in the upper reaches of the Yellow River, spanning from Yinchuan to Lanzhou. This study presents the first comprehensive report of the complete mitochondrial genome sequence of G. huanghensis, encompassing 16,604 base pairs (bp) with a nucleotide composition of 26.3% cytosine (C), 17.6% guanine (G), 29.4% adenine (A), and 26.7% thymine (T). In congruence with other species in the Gobio genus, its mitochondrial genome comprises 37 genes, including two ribosomal RNA genes, 13 protein-coding genes (PCGs), and 22 transfer RNA genes. Notably, COX1 initiates with the start codon GTG, distinct from the typical ATG start codon of other PCGs. The mitogenome exhibits four types of stop codons: TAA, TAG, TA-, and T--. Phylogenetic analyses, grounded in complete mitochondrial sequences, position G. huanghensis at the forefront of one of two major clusters within the genus Gobio, corroborating existing morphological classifications. These findings offer valuable theoretical insights for the taxonomic classification, conservation, and population genetics of G. huanghensis.
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Magnetic nanomaterial-mediated magnetic hyperthermia is a localized heating treatment modality that has been applied to treat aggressive cancer in clinics. In addition to being taken up by tumor cells to function in cancer therapy, magnetic nanomaterials can also be internalized by immune cells in the tumor microenvironment, which may contribute to regulating the anti-tumor immune effects. However, there exists little studies on the distribution of magnetic nanomaterials in different types of cells within tumor tissue. Herein, ferrimagnetic vortex-domain iron oxide nanorings (FVIOs) with or without the liver-cancer-targeting peptide SP94 have been successfully synthesized as a model system to investigate the effect of surface modification of FVIOs (with or without SP94) on the distribution of tumor cells and different immune cells in hepatocellular carcinoma (HCC) microenvironment of a mouse. The distribution ratio of FVIO-SP94s in tumor cells was 1.3 times more than that of FVIOs. Immune cells in the liver tumor microenvironment took up fewer FVIO-SP94s than FVIOs. In addition, myeloid cells were found to be much more amenable than lymphoid cells in terms of their ability to phagocytose nanoparticles. Specifically, the distributions of FVIOs/FVIO-SP94s in tumor-associated macrophages, dendritic cells, and myeloid-derived suppressor cells were 13.8%/12%, 3.7%/0.9%, and 6.3%/1.2%, respectively. While the distributions of FVIOs/FVIO-SP94s in T cells, B cells, and natural killer cells were 5.5%/0.7%, 3.0%/0.7%, and 0.4%/0.3%, respectively. The results described in this article enhance our understanding of the distribution of nanomaterials in the tumor microenvironment and provide a strategy for rational design of magnetic hyperthermia agents that can effectively regulate anti-tumor immune effects.
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Carcinoma Hepatocelular , Hipertermia Induzida , Neoplasias Hepáticas , Camundongos , Animais , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Hipertermia Induzida/métodos , Magnetismo , Fenômenos Magnéticos , Microambiente TumoralRESUMO
Alternative polyadenylation (APA), a posttranscriptional mechanism of gene expression via determination of 3'UTR length, has an emerging role in carcinogenesis. Although abundant APA reprogramming is found in kidney renal clear cell carcinoma (KIRC), which is one of the major malignancies, whether APA functions in KIRC remains unknown. Herein, we found that chromatin modifier MORC2 gained oncogenic potential in KIRC among the genes with APA reprogramming, and moreover, its oncogenic potential was enhanced by 3'UTR shortening through stabilization of MORC2 mRNA. MORC2 was found to function in KIRC by downregulating tumor suppressor DAPK1 via DNA methylation. Mechanistically, MORC2 recruited DNMT3A to facilitate hypermethylation of the DAPK1 promoter, which was strengthened by 3'UTR shortening of MORC2. Furthermore, loss of APA regulator NUDT21, which was induced by DNMT3B-mediated promoter methylation, was identified as responsible for 3'UTR shortening of MORC2 in KIRC. Additionally, NUDT21 was confirmed to act as a tumor suppressor mainly depending on downregulation of MORC2. Finally, we designed an antisense oligonucleotide (ASO) to enhance NUDT21 expression and validated its antitumor effect in vivo and in vitro. This study uncovers the DNMT3B/NUDT21/APA/MORC2/DAPK1 regulatory axis in KIRC, disclosing the role of APA in KIRC and the crosstalk between DNA methylation and APA.
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Carcinoma de Células Renais , Fator de Especificidade de Clivagem e Poliadenilação , Neoplasias Renais , Fatores de Transcrição , Humanos , Regiões 3' não Traduzidas , Carcinogênese/genética , Carcinoma de Células Renais/genética , Metilação de DNA , Neoplasias Renais/genética , Poliadenilação , Fatores de Transcrição/genética , Fator de Especificidade de Clivagem e Poliadenilação/genéticaRESUMO
Pharmaceutical companies have recently focused on accelerating the timeline for initiating first-in-human (FIH) trials to allow quick assessment of biologic drugs. For example, a stable cell pool can be used to produce materials for the toxicology (Tox) study, reducing time to the clinic by 4-5 months. During the coronavirus disease 2019 (COVID-19) pandemic, the anti-COVID drugs timeline from DNA transfection to the clinical stage was decreased to 6 months using a stable pool to generate a clinical drug substrate (DS) with limited stability, virus clearance, and Tox study package. However, a lean chemistry, manufacturing, and controls (CMC) package raises safety and comparability risks and may leave extra work in the late-stage development and commercialization phase. In addition, whether these accelerated COVID-19 drug development strategies can be applied to non-COVID projects and established as a standard practice in biologics development is uncertain. Here, we present a case study of a novel anti-tumor drug in which application of "fast-to-FIH" approaches in combination with BeiGene's de-risk strategy achieved successful delivery of a complete CMC package within 10 months. A comprehensive comparability study demonstrated that the DS generated from a stable pool and a single-cell-derived master cell bank were highly comparable with regards to process performance, product quality, and potency. This accomplishment can be a blueprint for non-COVID drug programs that approach the pace of drug development during the pandemic, with no adverse impact on the safety, quality, and late-stage development of biologics.
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Antineoplásicos , Produtos Biológicos , COVID-19 , Humanos , Anticorpos Monoclonais , Preparações Farmacêuticas , Antineoplásicos/uso terapêuticoRESUMO
Fall accidents can cause severe impacts on the physical health and the quality of life of those who suffer limb diseases or injuries, the elderly, and their caregivers. Moreover, the later the accident is discovered, the lower the chance of recovery of the injured one. In order to detect accidents earlier, we propose a data-driven human fall detection framework. By combining the sensing mechanism of a commercialized webcam and an ultrasonic sensor array, we develop a probability model for automatic human fall monitoring. The webcam and ultrasonic array respectively collect the transverse and longitudinal time-series signals from a moving subject, and then these signals are assembled as a three-dimensional (3D) movement trajectory map. We also use two different detection-tracking algorithms for recognizing the tracked subjects. The mean height of the subjects is 164.2 ± 12 cm. Based on the data density functional theory (DDFT), we use the 3D motion data to estimate the cluster numbers and their cluster boundaries. We also employ the Gaussian mixture model as the DDFT kernel. Then, we utilize those features to build a probabilistic model of human falling. The model visually exhibits three possible states of human motions: normal motion, transition, and falling. The acceptable detection accuracy and the small model size reveals the feasibility of the proposed hybridized platform. The time from starting the alarm to an actual fall is on average about 0.7 s in our platform. The proposed sensing mechanisms offer 90% accuracy, 90% sensitivity, and 95% precision in the data validation. Then these vital results validate that the proposed framework has comparable performance to the contemporary methods.
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Heat stroke has increased in frequency worldwide in recent years and continues to have a high morbidity and mortality. Identification of the mechanisms mediating heat stoke is important and necessary. Our preliminary study revealed heat stress (HS)-induced apoptosis of vascular endothelial cells was associated with reactive oxygen species (ROS)-induced p53 translocation into mitochondria. Previous studies have suggested the prolyl-isomerase Pin1 regulates p53 functioning through specific binding to p53 phosphorylation sites. Based on these studies, we presumed Pin1 is a key intermediate in regulation of mitochondrial p53 translocation through a HS-induced ROS-p53 transcription-independent apoptosis pathway. In this context, we revealed p53 had a crucial role in a HS-induced mitochondrial apoptotic pathway, where p53 protein rapidly translocated into mitochondria in endothelial cells both in vitro and in vivo. In particular, HS caused an increase in p53 phosphorylation at Ser46 that facilitated interactions with phosphorylation-dependent prolyl-isomerase Pin1, which has a key role in promoting HS-induced localization of p53 to mitochondria. Furthermore, we also found ROS production was a critical mediator in HS-induced Pin1/p53 signaling and was involved in regulating mitochondrial apoptosis pathway activation. Therefore, we have contributed to our profound understanding of the mechanism underlying HS-induced endothelial dysfunction in an effort to reduce the mortality and morbidity of heat stroke.