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1.
Neural Regen Res ; 20(2): 354-365, 2025 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38819039

RESUMO

Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor dysfunction. To date, no effective treatment exists as the exact causative mechanism remains unknown. Therefore, experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic targets. Since most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4, which is highly expressed on the membrane of astrocyte endfeet, most current experimental models are based on aquaporin-4-IgG that initially targets astrocytes. These experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders, such as aquaporin-4 loss, astrocytopathy, granulocyte and macrophage infiltration, complement activation, demyelination, and neuronal loss; however, they do not fully capture the pathological process of human neuromyelitis optica spectrum disorders. In this review, we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro, ex vivo, and in vivo for neuromyelitis optica spectrum disorders, suggest potential pathogenic mechanisms for further investigation, and provide guidance on experimental model choices. In addition, this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders, offering further therapeutic targets and a theoretical basis for clinical trials.

2.
Prog Neurobiol ; 240: 102654, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945516

RESUMO

Neuromyelitis optica (NMO) arises from primary astrocytopathy induced by autoantibodies targeting the astroglial protein aquaporin 4 (AQP4), leading to severe neurological sequelae such as vision loss, motor deficits, and cognitive decline. Mounting evidence has shown that dysregulated activation of complement components contributes to NMO pathogenesis. Complement C3 deficiency has been shown to protect against hippocampal neurodegeneration and cognitive decline in neurodegenerative disorders (e.g., Alzheimer's disease, AD) and autoimmune diseases (e.g., multiple sclerosis, MS). However, whether inhibiting the C3 signaling can ameliorate cognitive dysfunctions in NMO remains unclear. In this study, we found that the levels of C3a, a split product of C3, significantly correlate with cognitive impairment in our patient cohort. In response to the stimulation of AQP4 autoantibodies, astrocytes were activated to secrete complement C3, which inhibited the development of cultured neuronal dendritic arborization. NMO mouse models exhibited reduced adult hippocampal newborn neuronal dendritic and spine development, as well as impaired learning and memory functions, which could be rescued by decreasing C3 levels in astrocytes. Mechanistically, we found that C3a engaged with C3aR to impair neuronal development by dampening ß-catenin signalling. Additionally, inhibition of the C3-C3aR-GSK3ß/ß-catenin cascade restored neuronal development and ameliorated cognitive impairments. Collectively, our results suggest a pivotal role of the activation of the C3-C3aR network in neuronal development and cognition through mediating astrocyte and adult-born neuron communication, which represents a potential therapeutic target for autoimmune-related cognitive impairment diseases.

3.
J Craniofac Surg ; 35(4): 1143-1145, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38709070

RESUMO

INTRODUCTION: It is important to generate predictable statistical models by increasing the number of variables on the human skeletal and soft tissue structures on the face to increase the accuracy of human facial reconstructions. The purpose of this study was to determine mouth width 3-dimensionally based on statistical regression model. MATERIAL AND METHODS: Cone-beam computed tomography scan data from 130 individuals were used to measure the horizontal and vertical dimensions of orbital and nasal structures and intercanine width. The correlation between these hard tissue variables and the mouth width was evaluated using the statistical regression model. RESULTS: Orbital width, nasal width, and intercanine width were found to be strong predictors of the mouth width determination and were used to generate the regression formulae to find the most approximate position of the mouth. CONCLUSION: These specific variables may contribute to improving the accuracy of mouth width determination for oral and maxillofacial reconstructions.


Assuntos
Face , Reconstrução Mandibular , Boca , Análise de Regressão , Boca/anatomia & histologia , Boca/diagnóstico por imagem , Face/anatomia & histologia , Face/diagnóstico por imagem , Dente/anatomia & histologia , Dente/diagnóstico por imagem , Olho/anatomia & histologia , Olho/diagnóstico por imagem , Nariz/anatomia & histologia , Nariz/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Humanos
4.
Cell Rep ; 43(5): 114226, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38733586

RESUMO

Cognitive dysfunction is a feature in multiple sclerosis (MS), a chronic inflammatory demyelinating disorder. A notable aspect of MS brains is hippocampal demyelination, which is closely associated with cognitive decline. However, the mechanisms underlying this phenomenon remain unclear. Chitinase-3-like (CHI3L1), secreted by activated astrocytes, has been identified as a biomarker for MS progression. Our study investigates CHI3L1's function within the demyelinating hippocampus and demonstrates a correlation between CHI3L1 expression and cognitive impairment in patients with MS. Activated astrocytes release CHI3L1 in reaction to induced demyelination, which adversely affects the proliferation and differentiation of neural stem cells and impairs dendritic growth, complexity, and spine formation in neurons. Our findings indicate that the astrocytic deletion of CHI3L1 can mitigate neurogenic deficits and cognitive dysfunction. We showed that CHI3L1 interacts with CRTH2/receptor for advanced glycation end (RAGE) by attenuating ß-catenin signaling. The reactivation of ß-catenin signaling can revitalize neurogenesis, which holds promise for therapy of inflammatory demyelination.


Assuntos
Astrócitos , Proteína 1 Semelhante à Quitinase-3 , Cognição , Hipocampo , Neurogênese , Transdução de Sinais , Proteína 1 Semelhante à Quitinase-3/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Animais , Astrócitos/metabolismo , Humanos , Camundongos , Cognição/fisiologia , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Masculino , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/metabolismo , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Feminino , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , beta Catenina/metabolismo , Proliferação de Células , Diferenciação Celular
5.
Phytomedicine ; 129: 155610, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38640861

RESUMO

BACKGROUND: Lycium barbarum glycopeptide (LbGp), extracted from the traditional Chinese medicine (TCM) of Lycium barbarum (LB), provides a neuroprotective effect against neurodegenerative and neuroimmune disorders contributing to its immunomodulatory and anti-inflammatory roles. Neuromyelitis optica spectrum disorders (NMOSD) is an autoimmune-mediated central nervous system (CNS) demyelinating disease, clinically manifested as transverse myelitis (TM) and optic neuritis. However, no drug has been demonstrated to be effective in relieving limb weakness and visual impairment of NMOSD patients. PURPOSE: This study investigates the potential role of LbGp in ameliorating pathologic lesions and improving neurological dysfunction during NMOSD progression, and to elucidate the underlying mechanisms for the first time. STUDY DESIGN: We administrate LbGp in experimental NMOSD models in ex vivo and in vivo to explore its effect on NMOSD. METHODS: To evaluate motor function, both rotarod and gait tasks were performed in systemic NMOSD mice models. Furthermore, we assessed the severity of NMO-like lesions of astrocytes, organotypic cerebellar slices, as well as brain, spinal cord and optic nerve sections from NMOSD mouse models with LbGp treatment by immunofluorescent staining. In addition, demyelination levels in optic nerve were measured by G-ratio through Electro-microscopy (EM). And inflammation response was explored through detecting the protein levels of proinflammatory cytokines and NF-κB signaling in astrocytic culture medium and spinal cord homogenates respectively by Elisa and by Western blotting. RESULTS: LbGp could significantly reduce astrocytes injury, demyelination, and microglial activation in NMOSD models. In addition, LbGp also improved locomotor and visual dysfunction through preventing neuron and retinal ganglion cells (RGCs) from inflammatory attack in a systemic mouse model. Mechanistically, LbGp inhibits proinflammatory factors release via inhibition of NF-κB signaling in NMOSD models. CONCLUSION: This study provides evidence to develop LbGp as a functional TCM for the clinical treatment of NMOSD.


Assuntos
Modelos Animais de Doenças , Medicamentos de Ervas Chinesas , Neuromielite Óptica , Animais , Camundongos , Neuromielite Óptica/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Fármacos Neuroprotetores/farmacologia , NF-kappa B/metabolismo , Transtornos da Visão/tratamento farmacológico , Medula Espinal/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Astrócitos/efeitos dos fármacos
6.
Stem Cell Res Ther ; 15(1): 12, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38185703

RESUMO

BACKGROUND: Adipose-derived stem cells (ADSCs) have been extensively used in preclinical and clinical trials for treating various diseases. However, the differences between ADSCs from lean individuals (L-ADSCs) and those from obese individuals (O-ADSCs) have not been thoroughly investigated, particularly regarding their mitochondrial and lysosomal functions. Therefore, this study aims to evaluate the differences between L-ADSCs and O-ADSCs in terms of cell biological activity, mitochondria, and lysosomes. METHODS: We first isolated and cultured L-ADSCs and O-ADSCs. We then compared the differences between the two groups in terms of biological activity, including cell proliferation, differentiation potential, and their effect on the polarization of macrophages. Additionally, we observed the mitochondrial and lysosomal morphology of ADSCs using an electronic microscope, MitoTracker Red, and lysotracker Red dyes. We assessed mitochondrial function by examining mitochondrial membrane potential and membrane fluidity, antioxidative ability, and cell energy metabolism. Lysosomal function was evaluated by measuring autophagy and phagocytosis. Finally, we performed transcriptome analysis of the ADSCs using RNA sequencing. RESULTS: The biological activities of O-ADSCs were decreased, including cell immunophenotypic profiles, cell proliferation, and differentiation potential. Furthermore, compared to L-ADSCs, O-ADSCs promoted M1-type macrophage polarization and inhibited M2-type macrophage polarization. Additionally, the mitochondrial morphology of O-ADSCs was altered, with the size of the cells becoming smaller and mitochondrial fragments increasing. O-ADSCs also exhibited decreased mitochondrial membrane potential and membrane fluidity, antioxidative ability, and energy metabolism. With respect to lysosomes, O-ADSCs contained ungraded materials in their lysosomes, enhanced lysosomal permeability, and reduced autophagy and phagocytosis ability. RNA sequence analysis indicated that the signalling pathways related to cell senescence, cancer, and inflammation were upregulated, whereas the signalling pathways associated with stemness, cell differentiation, metabolism, and response to stress and stimuli were downregulated. CONCLUSIONS: This study indicates that ADSCs from individuals (BMI > 30 kg/m2) exhibit impaired mitochondrial and lysosomal function with decreased biological activity.


Assuntos
Lisossomos , Obesidade , Humanos , Obesidade/terapia , Fagocitose , Adiposidade , Antioxidantes , Células-Tronco
7.
NPJ Regen Med ; 9(1): 4, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38242900

RESUMO

Neuromyelitis optica (NMO) is a severe autoimmune inflammatory disease of the central nervous system that affects motor function and causes relapsing disability. Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have been used extensively in the treatment of various inflammatory diseases, due to their potent regulatory roles that can mitigate inflammation and repair damaged tissues. However, their use in NMO is currently limited, and the mechanism underlying the beneficial effects of hUC-MSCs on motor function in NMO remains unclear. In this study, we investigate the effects of hUC-MSCs on the recovery of motor function in an NMO systemic model. Our findings demonstrate that milk fat globule epidermal growth 8 (MFGE8), a key functional factor secreted by hUC-MSCs, plays a critical role in ameliorating motor impairments. We also elucidate that the MFGE8/Integrin αvß3/NF-κB signaling pathway is partially responsible for structural and functional recovery, in addition to motor functional enhancements induced by hUC-MSC exposure. Taken together, these findings strongly support the involvement of MFGE8 in mediating hUC-MSCs-induced improvements in motor functional recovery in an NMO mouse model. In addition, this provides new insight on the therapeutic potential of hUC-MSCs and the mechanisms underlying their beneficial effects in NMO.

8.
Br J Pharmacol ; 181(1): 125-141, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37538043

RESUMO

BACKGROUND AND PURPOSE: The low efficacy of mesenchymal stem cells (MSCs) has restricted their application in the treatment of liver disease. Emerging evidence suggested that ferroptosis may provoke hepatocyte dysfunction and exacerbate damage to the liver microenvironment. Here, we have investigated the contribution of liver ferroptosis to the elimination and effectiveness of human MSC (hMSC). Furthermore, potential links between liver ferroptosis and aryl hydrocarbon receptors (AhR) were explored. EXPERIMENTAL APPROACH: Two mouse models, iron supplement-induced hepatic ferroptosis and hepatic ischaemia/reperfusion (I/R) injury, were used to identify effects of ferroptosis on hMSC pharmacokinetics (PK)/pharmacodynamics (PD). KEY RESULTS: AhR inhibition attenuated hepatic ferroptosis and improved survival of hMSCs. hMSC viability was decreased by iron supplementation or serum from I/R mice. The AhR antagonist CH223191 reversed iron overload and oxidative stress induced by ferroptosis and increased hMSC concentration and efficacy in mouse models. Effects of CH223191 were greater than those of deferoxamine, a conventional ferroptosis inhibitor. Transcriptomic results suggested that the AhR-signal transducer and activator of transcription 3 (STAT3)-haem oxygenase 1/COX-2 signalling pathway is critical to this process. These results were confirmed in a mouse model of hepatic I/R injury. In mice pre-treated with CH223191, hMSC exhibited more potent protective effects, linked to decreased hepatic ferroptosis. CONCLUSION AND IMPLICATIONS: Our findings showed that ferroptosis was a critical factor in determining the fate of hMSCs. Inhibition of AhR decreased hepatic ferroptosis, thereby increasing survival and therapeutic effects of hMSCs in mouse models of liver disease.


Assuntos
Ferroptose , Hepatopatias , Humanos , Animais , Camundongos , Receptores de Hidrocarboneto Arílico/metabolismo , Ciclo-Oxigenase 2/metabolismo , Fator de Transcrição STAT3/metabolismo , Fígado/metabolismo , Ferro/metabolismo , Hepatopatias/metabolismo
9.
J Transl Med ; 21(1): 861, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017546

RESUMO

BACKGROUND: N6-methyladenosine (m6A) is the most prevalent RNA modification. Although hnRNPA2B1, as a reader of m6A modification, has been reported to promote tumorigenesis in a few types of tumors, its role in hepatocellular carcinoma (HCC) and the underlying molecular mechanism remains unclear. METHODS: Multiple public databases were used to analyze the expression of hnRNPA2B1 in HCC and its correlation with survival prognosis. We employed a CRISPR-Cas9 sgRNA editing strategy to knockout hnRNPA2B1 expression in HCC cells. The biological function of hnRNPA2B1 in vitro in HCC cells was measured by CCK8, colony formation, migration, and invasion assay. The tumorigenic function of hnRNPA2B1 in vivo was determined by a subcutaneous tumor formation experiment and a HCC mouse model via tail injection of several plasmids into the mouse within 5s-7s. RNA binding protein immunoprecipitation (RIP) experiment using hnRNPA2B1 was performed to test the target genes of hnRNPA2B1 and methylated RNA immunoprecipitation (MeRIP) assay was performed to explore the m6A methylated mRNA of target genes. RESULTS: hnRNPA2B1 highly expressed in HCC tissues, correlated with high grades and poor prognosis. Its knockout reduced HCC cell proliferation, migration, and invasion in vitro, while overexpression promoted these processes. hnRNPA2B1-knockout cells inhibited tumor formation in graft experiments. In HCC mice, endogenous knockout attenuated hepatocarcinogenesis. RNA-seq showed downregulated gluconeogenesis with high hnRNPA2B1 expression. hnRNPA2B1 negatively correlated with PCK1, a key enzyme. RIP assay revealed hnRNPA2B1 binding to PCK1 mRNA. hnRNPA2B1 knockout increased m6A-methylation of PCK1 mRNA. Interestingly, PCK1 knockout partially counteracted tumor inhibition by hnRNPA2B1 knockout in mice. CONCLUSION: Our study indicated that hnRNPA2B1 is highly expressed in HCC and correlated with a poor prognosis. hnRNPA2B1 promotes the tumorigenesis and progression of HCC both in vitro and in vivo. Moreover, hnRNPA2B1 downregulates the expression of PCK1 mRNA via a m6A methylation manner. More importantly, the ability of hnRNPA2B1 to induce tumorigenesis and progression in HCC is dependent on its ability to decrease the expression of PCK1. Therefore, this study suggested that hnRNPA2B1 might be a diagnostic marker of poor prognosis of HCC and a potential therapeutic target for HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/patologia , Metilação , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , RNA/metabolismo , RNA Guia de Sistemas CRISPR-Cas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética
10.
Sci Adv ; 9(39): eadg8148, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37756391

RESUMO

Chitinase-3-like protein 1 (CHI3L1) is primarily secreted by activated astrocytes in the brain and is known as a reliable biomarker for inflammatory central nervous system (CNS) conditions such as neurodegeneration and autoimmune disorders like neuromyelitis optica (NMO). NMO is an astrocyte disease caused by autoantibodies targeting the astroglial protein aquaporin 4 (AQP4) and leads to vision loss, motor deficits, and cognitive decline. In this study examining CHI3L1's biological function in neuroinflammation, we found that CHI3L1 expression correlates with cognitive impairment in our NMO patient cohort. Activated astrocytes secrete CHI3L1 in response to AQP4 autoantibodies, and this inhibits the proliferation and neuronal differentiation of neural stem cells. Mouse models showed decreased hippocampal neurogenesis and impaired learning behaviors, which could be rescued by depleting CHI3L1 in astrocytes. The molecular mechanism involves CHI3L1 engaging the CRTH2 receptor and dampening ß-catenin signaling for neurogenesis. Blocking this CHI3L1/CRTH2/ß-catenin cascade restores neurogenesis and improves cognitive deficits, suggesting the potential for therapeutic development in neuroinflammatory disorders.

11.
Cell Rep ; 42(9): 113022, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37610873

RESUMO

Cognitive impairment has been associated with an age-related decline in adult hippocampal neurogenesis (AHN). The molecular basis of declining neurogenesis in the aging hippocampus remains to be elucidated. Here, we show that pleiotrophin (PTN) expression is decreased with aging in neural stem and progenitor cells (NSPCs). Mice lacking PTN exhibit impaired AHN accompanied by poor learning and memory. Mechanistically, we find that PTN engages with protein tyrosine phosphatase receptor type Z1 (PTPRZ1) to promote NSPC proliferation and differentiation by activating AKT signaling. PTN overexpression or pharmacological activation of AKT signaling in aging mice restores AHN and alleviates relevant memory deficits. Importantly, we also find that PTN overexpression improves impaired neurogenesis in senescence-accelerated mouse prone 8 (SAMP8) mice. We further confirm that PTN is required for enriched environment-induced increases in AHN. These results corroborate the significance of AHN in aging and reveal a possible therapeutic intervention by targeting PTN.


Assuntos
Disfunção Cognitiva , Proteínas Proto-Oncogênicas c-akt , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Hipocampo/metabolismo , Neurogênese/fisiologia
12.
Mol Ther ; 31(9): 2715-2733, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37481702

RESUMO

Neuromyelitis optica (NMO) is an autoimmune inflammatory disease of the central nervous system (CNS) characterized by transverse myelitis and optic neuritis. The pathogenic serum IgG antibody against the aquaporin-4 (AQP4) on astrocytes triggers the activation of the complement cascade, causing astrocyte injury, followed by oligodendrocyte injury, demyelination, and neuronal loss. Complement C3 is positioned as a central player that relays upstream initiation signals to activate downstream effectors, potentially stimulating and amplifying host immune and inflammatory responses. However, whether targeting the inhibition of C3 signaling could ameliorate tissue injury, locomotor defects, and visual impairments in NMO remains to be investigated. In this study, using the targeted C3 inhibitor CR2-Crry led to a significant decrease in complement deposition and demyelination in both slice cultures and focal intracerebral injection models. Moreover, the treatment downregulated the expression of inflammatory cytokines and improved motor dysfunction in a systemic NMO mouse model. Similarly, employing serotype 2/9 adeno-associated virus (AAV2/9) to induce permanent expression of CR2-Crry resulted in a reduction in visual dysfunction by attenuating NMO-like lesions. Our findings reveal the therapeutic value of inhibiting the complement C3 signaling pathway in NMO.


Assuntos
Complemento C3 , Neuromielite Óptica , Animais , Camundongos , Complemento C3/genética , Complemento C3/metabolismo , Neuromielite Óptica/patologia , Aquaporina 4/metabolismo , Transtornos da Visão/complicações , Transtornos da Visão/patologia , Astrócitos/metabolismo , Transdução de Sinais , Proteínas Recombinantes de Fusão/metabolismo
13.
Front Public Health ; 11: 1138813, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37441642

RESUMO

Background: Childhood maltreatment has been identified as a risk factor for depressive symptoms. Social anxiety is closely associated with depression. Physical activity has been regarded as an underlying protective factor. Little is known about the complex relations among these factors in Chinese middle school students. This study aimed to explore whether social anxiety mediated the association between childhood maltreatment and depressive symptoms and investigate whether physical activity moderated the indirect or direct effect of the mediation model. Methods: A total of 1,570 middle school students were recruited and measured for childhood maltreatment (measured by Childhood Trauma Questionnaire-Short Form Chinese version), social anxiety (as the mediator, measured by the Chinese simplified version of Social Anxiety Scale for Adolescents), depressive symptoms (measured by the Chinese version of Depression Anxiety Stress Scales-21), physical activity (as the moderator), and covariates such as age, sex, and nationality. The proposed relationships were tested using mediation and moderated mediation models. Results: Emotional abuse was directly associated with depression, and the association between emotional abuse and depression was partially mediated by social anxiety. The associations between emotional abuse with depression and with social anxiety were moderated by physical activity. Conclusion: This study revealed the mediating role of social anxiety and the moderating role of physical activity between emotional abuse and depression, which emphasizes the potential benefits of sufficient physical activity to reduce social anxiety and depressive symptoms, and more intervention studies should be conducted to explore the direct influence of sufficient physical activity in the future.


Assuntos
Depressão , Abuso Emocional , Humanos , Adolescente , Depressão/psicologia , Ansiedade
14.
Opt Express ; 31(12): 19491-19509, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381363

RESUMO

Using a freeform optical surface can effectively reduce the imaging system weight and volume while maintaining good performance and advanced system specifications. But it is still very difficult for traditional freeform surface design when ultra-small system volume or ultra-few elements are required. Considering the images generated by the system can be recovered by digital image processing, in this paper, we proposed a design method of compact and simplified off-axis freeform imaging systems using optical-digital joint design process, which fully integrates the design of a geometric freeform system and the image recovery neural network. This design method works for off-axis nonsymmetric system structure and multiple freeform surfaces with complicated surface expression. The overall design framework, ray tracing, image simulation and recovery, and loss function establishment are demonstrated. We use two design examples to show the feasibility and effect of the framework. One is a freeform three-mirror system with a much smaller volume than a traditional freeform three-mirror reference design. The other is a freeform two-mirror system whose element number is reduced compared with the three-mirror system. Ultra-compact and/or simplified freeform system structure as well as good output recovered images can be realized.

15.
Front Plant Sci ; 14: 1133060, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37077629

RESUMO

Introduction: Crop pests have a great impact on the quality and yield of crops. The use of deep learning for the identification of crop pests is important for crop precise management. Methods: To address the lack of data set and poor classification accuracy in current pest research, a large-scale pest data set named HQIP102 is built and the pest identification model named MADN is proposed. There are some problems with the IP102 large crop pest dataset, such as some pest categories are wrong and pest subjects are missing from the images. In this study, the IP102 data set was carefully filtered to obtain the HQIP102 data set, which contains 47,393 images of 102 pest classes on eight crops. The MADN model improves the representation capability of DenseNet in three aspects. Firstly, the Selective Kernel unit is introduced into the DenseNet model, which can adaptively adjust the size of the receptive field according to the input and capture target objects of different sizes more effectively. Secondly, in order to make the features obey a stable distribution, the Representative Batch Normalization module is used in the DenseNet model. In addition, adaptive selection of whether to activate neurons can improve the performance of the network, for which the ACON activation function is used in the DenseNet model. Finally, the MADN model is constituted by ensemble learning. Results: Experimental results show that MADN achieved an accuracy and F1Score of 75.28% and 65.46% on the HQIP102 data set, an improvement of 5.17 percentage points and 5.20 percentage points compared to the pre-improvement DenseNet-121. Compared with ResNet-101, the accuracy and F1Score of MADN model improved by 10.48 percentage points and 10.56 percentage points, while the parameters size decreased by 35.37%. Deploying models to cloud servers with mobile application provides help in securing crop yield and quality.

16.
Biotechnol Genet Eng Rev ; : 1-11, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36856531

RESUMO

OBJECTIVE: To investigate the influence of physical exercise on insomnia and suicide among college students. METHODS: A total of 8095 college students in Changsha were selected by cluster sampling and investigated with self-made general condition scale, physical activity scale and Athens insomnia scale. The multivariate Logistic regression analysis was used to explore the risk factors of insomnia and suicide among college students. RESULTS: A total of 1859 college students (22.9%) were found to have insomnia behaviors. Of these, 763 (41%) and 1096 (59%) undergraduates had suicidal thoughts. The results of multivariate Logistic regression analysis showed that physical disease history, smoking, alcohol consumption, suicidal ideation, suicidal attempt and physical activity (P < 0.05) were all the independent influencing factors for insomnia among college students. Gender, physical disease history, suicide plan, suicide attempt, and physical activity (P < 0.05) were the independent influencing factors of suicidal ideation in insomnia college students. CONCLUSION: The detection rate of suicidal ideation is high in insomnia college students. Physical disease history, suicide attempt and physical activity may be the related factors of suicidal ideation. Physical activity was the influencing factor of college students' insomnia behavior, and heavy exercise was the independent protection factor of college students' insomnia behavior. At the same time, heavy exercise was a protective factor for insomnia college students with suicidal ideation.

17.
Front Public Health ; 11: 1100069, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36908470

RESUMO

Objectives: Cyberbullying is quite common in adolescents and college students, and it influences mental health in many aspects. The purpose of this study was to investigate the prevalence of cyberbullying in Chinese college students and to look for related factors. Methods: Eight thousand and ninety-eight college students aged 17-26 were enrolled in this cross-sectional study. We collected information of their sociodemographic data, depression (evaluated by Self-Rating Depression Scale), anxiety (evaluated by Self-Rating Anxiety Scale), lifetime suicidal behaviors (including suicidal ideation, suicidal plans, and suicide attempts), and experiences of cyberbullying for the past 12 months by online questionnaires. Results: The prevalence of cyberbullying for the past 12 months was 7.82% (633/8,098) among college students. Binary logistic regression analysis showed that sex (odds ratio, OR = 0.522, 95%CI = 0.433-0.629, p < 0.001), suicide attempts (OR = 2.164, 95%CI = 1.589-2.948, p < 0.001), depression (OR = 2.372, 95%CI = 1.602-3.512, p < 0.001), and anxiety (OR = 1.911, 95%CI = 1.305-2.800, p = 0.001) were independently associated with cyberbullying. Conclusion: Cyberbullying is very common among college students in Hunan Province, China. Besides, being male, suicide attempts, depression and anxiety were independently associated with cyberbullying, which highlights the importance of paying attention to cyberbullying and addressing anxiety, depression, and suicidal behaviors among college students to better improve their mental health and prevent suicide.


Assuntos
Cyberbullying , Adolescente , Humanos , Masculino , Feminino , Cyberbullying/psicologia , Prevalência , Estudos Transversais , Tentativa de Suicídio , Estudantes
18.
Glia ; 71(2): 284-304, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36089914

RESUMO

Neuromyelitis optica spectrum disorder (NMOSD) is a severe inflammatory autoimmune disease of the central nervous system that is manifested as secondary myelin loss. Oligodendrocyte progenitor cells (OPCs) are the principal source of myelinating oligodendrocytes (OLs) and are abundant in demyelinated regions of NMOSD patients, thus possibly representing a cellular target for pharmacological intervention. To explore the therapeutic compounds that enhance myelination due to endogenous OPCs, we screened the candidate drugs in mouse neural progenitor cell (NPC)-derived OPCs. We identified drug edaravone, which is approved by the Food and Drug Administration (FDA), as a promoter of OPC differentiation into mature OLs. Edaravone enhanced remyelination in organotypic slice cultures and in mice, even when edaravone was administered following NMO-IgG-induced demyelination, and ameliorated motor impairment in a systemic mouse model of NMOSD. The results of mechanistic studies in NMO-IgG-treated mice and the biopsy samples of the brain tissues of NMOSD patients indicated that the mTORC1 signaling pathway was significantly inhibited, and edaravone promoted OPC maturation and remyelination by activating mTORC1 signaling. Furthermore, pharmacological activation of mTORC1 signaling significantly enhanced myelin regeneration in NMOSD. Thus, edaravone is a potential therapeutic agent that promotes lesion repair in NMOSD patients by enhancing OPC maturation.


Assuntos
Neuromielite Óptica , Remielinização , Animais , Camundongos , Remielinização/fisiologia , Neuromielite Óptica/tratamento farmacológico , Edaravone/metabolismo , Bainha de Mielina/metabolismo , Oligodendroglia/metabolismo , Diferenciação Celular/fisiologia , Transdução de Sinais , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Imunoglobulina G
19.
Front Public Health ; 10: 1017375, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36452957

RESUMO

Introduction: The most frequent complications after abdominal surgery include a decrease or loss of appetite, abdominal distension, abdominal pain caused by reduced gastrointestinal motility, anal arrest with intestinal distension and defecation, and nausea and vomiting due to anesthetic and opioid analgesic administration. These complications severely affect postoperative recovery, prolong hospital stay, and increase the financial burden. The objective of this study is to investigate the efficacy and safety of three acupoint stimulation modalities (electroacupuncture [EA], transcutaneous electrical acupoint stimulation [TEAS], and transcutaneous acupoint electrical stimulation combined with EA [TEAS+EA]), and two EA instrument waveforms (continuous wave and dilatational wave) for rapid recovery after abdominal surgery. Methods and analysis: A total of 560 patients will be recruited and randomly allocated to receive one of the following seven interventions: continuous wave EA, continuous wave TEAS, continuous wave TEAS + EA, dilatational wave EA, dilatational wave TEAS, dilatational wave TEAS + EA, and a control. For this study, continuous waves at 2 Hz, and dilatational waves at 2/50 Hz would be selected. The points to be stimulated by EA are the bilateral Neiguan (PC6), Hegu (LI6), Zusanli (ST36), Shangjuxu (ST37), and Xiajuxu (ST39), and TEAS would stimulate the bilateral Liangmen (ST21) and Daheng (SP15). The control group will neither receive EA nor TEAS. All patients will undergo an enhanced recovery plan after surgery and be provided with standardized perioperative management. Treatment will start on the first postoperative day and be administered once daily in the morning until the patient regains spontaneous bowel movements and can tolerate oral intake of solid food. The primary outcome is a composite of time to first defecation and time to tolerance of a solid diet. Secondary outcomes include time to first exhaustion; time of first defecation; time of tolerance of a solid diet; time to the first ambulation; length of hospital stay from surgery to discharge; visual analog scale score for postoperative daily pain, nausea, and vomiting; incidence of postoperative complications; and treatment acceptability. Discussion: This study will compare the efficacy and safety of three acupoint stimulation methods and two EA instrument waveforms for rapid recovery after abdominal surgery. Trial Registration: Chinese Clinical Trial Registry (http://www.chictr.org.cn), ChiCTR2100043883.


Assuntos
Eletroacupuntura , Humanos , Pontos de Acupuntura , Náusea , Vômito , Tempo de Internação , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Animals (Basel) ; 12(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36290198

RESUMO

High-altitude stress threatens the survival rate of Tibetan sheep and reduces their fertility. However, the molecular basis of this phenomenon remains elusive. Here, we used RNA-seq to elucidate the transcriptome dynamics of high-altitude stress in Tibetan sheep ovaries. In total, 104 genes were characterized as high-altitude stress-related differentially expressed genes (DEGs). In addition, 36 DEGs contributed to ovarian follicle development, and 28 of them were downregulated under high-altitude stress. In particular, high-altitude stress significantly suppressed the expression of two ovarian lymphatic system marker genes: LYVE1 and ADAMTS-1. Network analysis revealed that luteinizing hormone (LH)/follicle-stimulating hormone (FSH) signaling-related genes, such as EGR1, FKBP5, DUSP1, and FOS, were central regulators in the DEG network, and these genes were also suppressed under high-altitude stress. As a post-transcriptional regulation mechanism, alternative splicing (AS) is ubiquitous in Tibetan sheep. High-altitude stress induced 917 differentially alternative splicing (DAS) events. High-altitude stress modulated DAS in an AS-type-specific manner: suppressing skipped exon events but increasing retained intron events. C2H2-type zinc finger transcription factors and RNA processing factors were mainly enriched in DAS. These findings revealed high-altitude stress repressed ovarian development by suppressing the gene expression of LH/FSH hormone signaling genes and inducing intron retention of C2H2-type zinc finger transcription factors.

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