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Eastern equine encephalitis virus (EEEV) is the most virulent alphavirus that infects humans, and many survivors develop neurological sequelae, including paralysis and intellectual disability. Alphavirus spike proteins comprise trimers of heterodimers of glycoproteins E2 and E1 that mediate binding to cellular receptors and fusion of virus and host cell membranes during entry. We recently identified very-low density lipoprotein receptor (VLDLR) and apolipoprotein E receptor 2 (ApoER2) as cellular receptors for EEEV and a distantly related alphavirus, Semliki Forest virus (SFV). Here, we use single-particle cryo-electron microscopy (cryo-EM) to determine structures of the EEEV and SFV spike glycoproteins bound to the VLDLR ligand-binding domain and found that EEEV and SFV interact with the same cellular receptor through divergent binding modes. Our studies suggest that the ability of LDLR-related proteins to interact with viral spike proteins through very small footprints with flexible binding modes results in a low evolutionary barrier to the acquisition of LDLR-related proteins as cellular receptors for diverse sets of viruses.
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Microscopia Crioeletrônica , Vírus da Encefalite Equina do Leste , Receptores de LDL , Receptores de LDL/metabolismo , Receptores de LDL/química , Vírus da Encefalite Equina do Leste/metabolismo , Vírus da Encefalite Equina do Leste/ultraestrutura , Humanos , Animais , Vírus da Floresta de Semliki/metabolismo , Ligação Proteica , Receptores Virais/metabolismo , Receptores Virais/química , Proteínas do Envelope Viral/metabolismo , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/ultraestrutura , Modelos MolecularesRESUMO
Neuropathic pain (NP) is associated with astrocytes activation induced by nerve injury. Reactive astrocytes, strongly induced by central nervous system damage, can be classified into A1 and A2 types. Vitexin, a renowned flavonoid compound, is known for its anti-inflammatory and analgesic properties. However, its role in NP remains unexplored. This study aims to investigate the effects of vitexin on astrocyte polarization and its underlying mechanisms. A mouse model of NP was established, and primary astrocytes were stimulated with sphingosine-1-phosphate (S1P) to construct a cellular model. The results demonstrated significant activation of spinal astrocytes on days 14 and 21. Concurrently, reactive astrocytes predominantly differentiated into the A1 type. Western blot analysis revealed an increase in A1 astrocyte-associated protein (C3) and a decrease in A2 astrocyte-associated protein (S100A10). Serum S1P levels increased on days 14 and 21, alongside a significant upregulation of Sphingosine-1-phosphate receptor 1 (S1PR1) mRNA expression and elevated expression of chemokines. In vitro, stimulation with S1P inhibited the Phosphatidylinositol 3-kinase and protein kinase B (PI3K/Akt) signaling pathway and autophagy flux, promoting polarization of astrocytes towards the A1 phenotype while suppressing the polarization of A2 astrocytes. Our findings suggest that vitexin, acting on astrocytes but not microglia, attenuates S1P-induced downregulation of PI3K/Akt signaling, restores autophagy flux in astrocytes, regulates A1/A2 astrocyte ratio, and reduces chemokine and S1P secretion, thereby alleviating neuropathic pain caused by nerve injury.
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Western equine encephalitis virus (WEEV) is an arthropod-borne virus (arbovirus) that frequently caused major outbreaks of encephalitis in humans and horses in the early twentieth century, but the frequency of outbreaks has since decreased markedly, and strains of this alphavirus isolated in the past two decades are less virulent in mammals than strains isolated in the 1930s and 1940s1-3. The basis for this phenotypic change in WEEV strains and coincident decrease in epizootic activity (known as viral submergence3) is unclear, as is the possibility of re-emergence of highly virulent strains. Here we identify protocadherin 10 (PCDH10) as a cellular receptor for WEEV. We show that multiple highly virulent ancestral WEEV strains isolated in the 1930s and 1940s, in addition to binding human PCDH10, could also bind very low-density lipoprotein receptor (VLDLR) and apolipoprotein E receptor 2 (ApoER2), which are recognized by another encephalitic alphavirus as receptors4. However, whereas most of the WEEV strains that we examined bind to PCDH10, a contemporary strain has lost the ability to recognize mammalian PCDH10 while retaining the ability to bind avian receptors, suggesting WEEV adaptation to a main reservoir host during enzootic circulation. PCDH10 supports WEEV E2-E1 glycoprotein-mediated infection of primary mouse cortical neurons, and administration of a soluble form of PCDH10 protects mice from lethal WEEV challenge. Our results have implications for the development of medical countermeasures and for risk assessment for re-emerging WEEV strains.
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Vírus da Encefalite Equina do Oeste , Especificidade de Hospedeiro , Protocaderinas , Receptores Virais , Animais , Feminino , Humanos , Masculino , Camundongos , Aves/metabolismo , Aves/virologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , Vírus da Encefalite Equina do Oeste/classificação , Vírus da Encefalite Equina do Oeste/metabolismo , Vírus da Encefalite Equina do Oeste/patogenicidade , Encefalomielite Equina/epidemiologia , Encefalomielite Equina/virologia , Proteínas Relacionadas a Receptor de LDL/metabolismo , Neurônios/metabolismo , Neurônios/virologia , Fenótipo , Protocaderinas/metabolismo , Receptores de LDL/metabolismo , Receptores de LDL/genética , Receptores Virais/metabolismo , Proteínas do Envelope Viral/metabolismo , Zoonoses Virais/epidemiologia , Zoonoses Virais/virologiaRESUMO
BACKGROUND: Additional resection for invasive cancer at perihilar cholangiocarcinoma (pCCA) resection margins has become a consensus. However, controversy still exists regarding whether additional resection is necessary for residual biliary intraepithelial neoplasia (BilIN). METHOD: Consecutive patients with pCCA from two hospitals were enrolled. The incidence and pattern of resection margin BilIN were summarized. Prognosis between patients with negative margins (R0) and BilIN margins were analyzed. Cox regression with a forest plot was used to identify independent risk factors associated with overall survival (OS) and recurrence-free survival (RFS). Subgroup analysis was performed based on BilIN features and tumor characteristics. RESULTS: 306 pCCA patients receiving curative resection were included. 255 had R0 margins and 51 had BilIN margins. There was no significant difference in OS (P = 0.264) or RFS (P = 0.149) between the two group. Specifically, 19 patients with BilIN at distal bile ducts and 32 at proximal bile ducts. 42 patients showed low-grade BilIN, and 9 showed high-grade. Further analysis revealed no significant difference in long-term survival between different locations (P = 0.354), or between different grades (P = 0.772). Portal vein invasion, poor differentiation and lymph node metastasis were considered independent risk factors for OS and RFS, while BilIN was not. Subgroup analysis showed no significant difference in long-term survival between the lymph node metastasis subgroup, or between the portal vein invasion subgroup. CONCLUSION: For pCCA patients underwent curative resection, residual BilIN at resection margin is acceptable. Additional resection is not necessary for such patients to achieve absolute R0 margin.
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Neoplasias dos Ductos Biliares , Tumor de Klatskin , Margens de Excisão , Humanos , Masculino , Feminino , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/mortalidade , Estudos Retrospectivos , Tumor de Klatskin/cirurgia , Tumor de Klatskin/patologia , Tumor de Klatskin/mortalidade , Pessoa de Meia-Idade , Idoso , Prognóstico , Seguimentos , Taxa de Sobrevida , Carcinoma in Situ/cirurgia , Carcinoma in Situ/patologia , Neoplasia Residual/patologia , Neoplasia Residual/cirurgia , Adulto , Transformação Celular Neoplásica/patologia , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Hepatectomia/métodos , Hepatectomia/mortalidade , Idoso de 80 Anos ou maisRESUMO
BACKGROUND: Comorbid chronic neuropathic pain (NPP) and anxio-depressive disorders (ADD) have become a serious global public-health problem. The SLIT and NTRK-like 1 (SLITRK1) protein is important for synaptic remodeling and is highly expressed in the amygdala, an important brain region involved in various emotional behaviors. We examined whether SLITRK1 protein in the amygdala participates in NPP and comorbid ADD. METHODS: A chronic NPP mouse model was constructed by L5 spinal nerve ligation; changes in chronic pain and ADD-like behaviors were measured in behavioral tests. Changes in SLITRK1 protein and excitatory synaptic functional proteins in the amygdala were measured by immunofluorescence and Western blot. Adeno-associated virus was transfected into excitatory synaptic neurons in the amygdala to up-regulate the expression of SLITRK1. RESULTS: Chronic NPP-related ADD-like behavior was successfully produced in mice by L5 ligation. We found that chronic NPP and related ADD decreased amygdalar expression of SLITRK1 and proteins important for excitatory synaptic function, including Homer1, postsynaptic density protein 95 (PSD95), and synaptophysin. Virally-mediated SLITRK1 overexpression in the amygdala produced a significant easing of chronic NPP and ADD, and restored the expression levels of Homer1, PSD95, and synaptophysin. CONCLUSION: Our findings indicated that SLITRK1 in the amygdala plays an important role in chronic pain and related ADD, and may prove to be a potential therapeutic target for chronic NPP-ADD comorbidity.
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Tonsila do Cerebelo , Comportamento Animal , Dor Crônica , Proteína 4 Homóloga a Disks-Large , Proteínas do Tecido Nervoso , Neuralgia , Animais , Masculino , Camundongos , Tonsila do Cerebelo/metabolismo , Ansiedade/metabolismo , Ansiedade/fisiopatologia , Transtornos de Ansiedade/metabolismo , Transtornos de Ansiedade/fisiopatologia , Comportamento Animal/fisiologia , Dor Crônica/metabolismo , Dor Crônica/fisiopatologia , Depressão/metabolismo , Depressão/etiologia , Depressão/fisiopatologia , Transtorno Depressivo/metabolismo , Transtorno Depressivo/fisiopatologia , Modelos Animais de Doenças , Proteína 4 Homóloga a Disks-Large/metabolismo , Proteínas de Arcabouço Homer/metabolismo , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/metabolismo , Neuralgia/metabolismo , Sinaptofisina/metabolismoRESUMO
Neuropathic pain (NPP) is a common type of chronic pain. Glial cells, including astrocytes (AS), are believed to play an important role in the progression of NPP. AS cells can be divided into various types based on their expression profiles, among which A1 and A2 types have clear functions. A1-type AS cells are neurotoxic, while A2-type AS cells exert neuroprotective functions. Some types of lysophosphatidic acid receptors (LPAR) have been shown to play a role in NPP. However, it remains unclear how AS cells and LPAR6 affect the occurrence and progression of NPP. In this study, we established a mouse model of chronic constriction injury (CCI) to simulate NPP. It was found that the expression of LPAR6 in AS cells of the spinal dorsal horn was increased in the CCI model, and the thresholds of mechanical and thermal pain were elevated after knocking out LPAR6, indicating that LPAR6 and AS cells participated in the occurrence of NPP. The experiment involved culturing primary AS cells and knocking down LPAR6 by Lentivirus. The results showed that the NF-κB signal pathway was activated and the number of A1-type AS cells increased in the CCI model. However, LPAR6 knockdown inhibited the NF-κB signal pathway and A1-type AS cells. The results of the mRNA sequencing and immunoprecipitation test indicate an interaction between LPAR6 and ROCK2. Inhibiting ROCK2 by Y-27632 increased mechanical and thermal pain thresholds and alleviated NPP at the molecular level. The study presents evidence that LPAR6 activates the NF-κB pathway through ROCK2 and contributes to the progression of NPP by increasing A1-type AS and decreasing A2-type AS. This suggests that LPAR6 could be a potential therapeutic target for alleviating NPP. Clinical applications that are successful can offer new therapeutic options, enhance the quality of life for patients, and potentially uncover new mechanisms for pain modulation.
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BACKGROUND: Fungal keratitis (FK) is a kind of infectious keratopathy with a high rate of blindness worldwide. Deoxynivalenol (DON) has been proven to have multiple toxic effects on humans and animals. OBJECTIVES: The aim of this study was to explore a possible pathogenic role of DON in FK. METHODS: We first made an animal model of FK in New Zealand white rabbits, and then attempted to detect DON in a culture medium in which Fusarium solani had been grown and also in the corneal tissue of the animal model of Fusarium solani keratitis. Next, a model of DON damage in human corneal epithelial cells (HCECs) was constructed to evaluate effects of DON on the activity, migration ability, cell cycle, and apoptosis in the HCECs. Then, putative the toxic damaging effects of DON on rabbit corneal epithelial cells and the impact of the repair cycle were studied. The expression levels of inflammatory factors in the corneas of the animal model and in the model of DON-damaged HCECs were measured. RESULTS: The Fusarium solani strain used in this study appeared to have the potential to produce DON, since DON was detected in the corneal tissue of rabbits which had been inoculated with this Fusarium solani strain. DON was found to alter the morphology of HCECs, to reduce the activity and to inhibit the proliferation and migration of HCECs. DON also induced the apoptosis and S-phase arrest of HCECs. In addition, DON was found to damage rabbit corneal epithelial cells, to prolong the corneal epithelial regeneration cycle, and to be associated with the upregulated expression of inflammatory factors in HCECs and rabbit corneas. CONCLUSIONS: DON appears to have a toxic damaging effect on HCECs in FK, and to induce the expression of inflammatory factors, leading to the exacerbation of keratitis and the formation of new blood vessels. Future studies will explore the possibility of developing a test to detect DON in ophthalmic settings to aid the rapid diagnosis of FK, and to develop DON neutralizers and adsorbents which have the potential to improve keratocyte status, inhibit apoptosis, and alleviate inflammation, therein providing new thinking for therapy of clinical FK.
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Úlcera da Córnea , Infecções Oculares Fúngicas , Fusarium , Ceratite , Tricotecenos , Humanos , Coelhos , Animais , Ceratite/microbiologia , Células EpiteliaisRESUMO
PURPOSE: Blood culture (BC) remains the gold standard for the diagnosis of bloodstream infections. Improving the quality of clinical BC samples, optimizing BC performance, and accelerating antimicrobial susceptibility test (AST) results are essential for the early detection of bloodstream infections and specific treatments. METHODS: We conducted a retrospective multicenter study using 450,845 BC specimens from clinical laboratories obtained from 19 teaching hospitals between 1 January 2021 and 31 December 2021. We evaluated key performance indicators (KPIs), turnaround times (TATs), and frequency distributions of processing in BC specimens. We also evaluated the AST results of clinically significant isolates for four different laboratory workflow styles. RESULTS: Across the 10 common bacterial isolates (n = 16,865) and yeast isolates (n = 1011), the overall median (interquartile range) TATs of AST results were 2.67 (2.05-3.31) and 3.73 (2.98-4.64) days, respectively. The specimen collections mainly occurred between 06:00 and 24:00, and specimen reception and loadings mainly between 08:00 and 24:00. Based on the laboratory workflows of the BCs, 16 of the 19 hospitals were divided into four groups. Time to results (TTRs) from specimen collection to the AST reports were 2.35 (1.95-3.06), 2.61 (1.98-3.32), 2.99 (2.60-3.87), and 3.25 (2.80-3.98) days for groups I, II, III, and IV, respectively. CONCLUSION: This study shows the related BC KPIs and workflows in different Chinese hospitals, suggesting that laboratory workflow optimization can play important roles in shortening time to AST reports and initiation of appropriate timely treatment.
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Laboratórios , Sepse , Humanos , Hemocultura , Laboratórios Clínicos , Fatores de Tempo , Hospitais de Ensino , Sepse/diagnósticoRESUMO
Alphaviruses are arthropod-borne enveloped RNA viruses that include several important human pathogens with outbreak potential. Among them, eastern equine encephalitis virus (EEEV) is the most virulent, and many survivors develop neurological sequelae, including paralysis and intellectual disability. The spike proteins of alphaviruses comprise trimers of heterodimers of their envelope glycoproteins E2 and E1 that mediate binding to cellular receptors and fusion of virus and host cell membranes during entry. We recently identified very-low density lipoprotein receptor (VLDLR) and apolipoprotein E receptor 2 (ApoER2), two closely related proteins that are expressed in the brain, as cellular receptors for EEEV and a distantly related alphavirus, Semliki forest virus (SFV) 1 . The EEEV and SFV spike glycoproteins have low sequence homology, and how they have evolved to bind the same cellular receptors is unknown. Here, we used single-particle cryo-electron microscopy (cryo-EM) to determine structures of the EEEV and SFV spike glycoproteins bound to the VLDLR ligand-binding domain. The structures reveal that EEEV and SFV use distinct surfaces to bind VLDLR; EEEV uses a cluster of basic residues on the E2 subunit of its spike glycoprotein, while SFV uses two basic residues at a remote site on its E1 glycoprotein. Our studies reveal that different alphaviruses interact with the same cellular receptor through divergent binding modes. They further suggest that the ability of LDLR-related proteins to interact with viral spike proteins through very small footprints with flexible binding modes results in a low evolutionary barrier to the acquisition of LDLR-related proteins as cellular receptors for diverse sets of viruses.
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(-)-5-Methylmellein (1) and its new dimer (2) were isolated from cultures of the basidiomycete Inonotus sinensis. Their structures were elucidated on the basis of extensive spectroscopic methods including UV, IR, HR-EI-MS, 1D NMR and 2D NMR. The structure of Compound 2 was determined by single-crystal X-ray crystallographic analysis. Compound 2 was tested for the cytotoxicities against five human cancer cell lines.
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Basidiomycota , Inonotus , Humanos , Estrutura Molecular , Basidiomycota/química , Linhagem Celular TumoralRESUMO
A hydrogel system loaded with mesenchymal stem cell-derived exosome (MSC-Exos) is an attractive new tool for tissue regeneration. However, the effect of the stiffness of exosome-loaded hydrogels on tissue regeneration is unclear. Here, the role of exosome-loaded hydrogel stiffness, during the regeneration of injured nerves, was assessed in vivo. The results showed that the photocrosslinkable hyaluronic acid methacrylate hydrogel stiffness plays an important role in repairing nerve injury. Compared with the stiff hydrogels loaded with exosomes, soft hydrogels loaded with exosomes showed better repair of injured peripheral nerves. The soft hydrogel promoted nerve repair by quickly releasing exosomes to inhibit the infiltration of macrophages and the expression of the proinflammatory factors IL-1ß and TNF-α in injured nerves. Our work revealed that exosome-loaded hydrogel stiffness plays an important role in tissue regeneration by regulating exosome release behavior and provided important clues for the clinical application of biological scaffold materials.
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Antimicrobial resistance (AMR) has been a leading issue for human health globally threatening the achievement of several of the Sustainable Development Goals (SDGs). Originated from Bacillus cereus, carbapenemases phenotype has been considered to be a major concern in AMR. In this study, the AMR identification rate of P. aeruginosa isolates and infections in FAHJU showed an obvious upward trend from 2012 to 2016. All 88 carbapenem-resistant P. aeruginosa strains were screened for carbapenemase phenotype by modified Carbapenem Inactivation Method (mCIM), and these results of mCIM were compared with traditional PCR results. The isolates of P. aeruginosa and infected patients showed obvious upward trend from 2012 to 2016. The drug resistance to common clinical antibiotics was serious that the clinical rational use of antibiotics should be strengthened, which is in accordance with the Global Antimicrobial Resistance and Use Surveillance System (GLASS) report. In comparison, the results of mCIM showed that 18 out of 88 CRPA strains were carbapenemase positive, which were completely consistent with the results yielded by PCR method. Therefore, it is convinced that this mCIM methodology is a simple and quick method for detected carbapenemases producing P. aeruginosa and has a potential capability in carbapenemases phenotype of pathogen like B. cereus, which will undoubtedly aid in the AMR therapy.
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Infecções por Pseudomonas , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Bacillus cereus/genética , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Fenótipo , Pseudomonas aeruginosa/genética , beta-Lactamases/genéticaRESUMO
Purpose: Fusarium Solani is the principal pathogen associated with fungal keratitis. As a sensitive drug to F. Solani, natamycin (NAT) was limited by the poor penetration and low bioavailability in clinical application. The aim of this study was to develop a new type of tri-block polymer nanoparticle-gel complex (Gel@PLGA-PEI-PEG@NAT) for delivering NAT and evaluate its physicochemical properties, antifungal activity, safety, penetrability, adhesion, and efficacy in treating fungal keratitis. Methods: PLGA-PEI-PEG@NAT was prepared and characterized with a nano-particle size analyzer, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The minimum inhibitory concentration (MIC), cytotoxicity, penetrability of NAT (Natacyn® 5% ophthalmic suspension; Alcon) and PLGA-PEI-PEG@NAT with different concentrations were assessed. The eye surface retention time, ocular irritation, and curative effect of the NAT ophthalmic suspension and Gel@PLGA-PEI-PEG@NAT on a rabbit fungal keratitis model were evaluated. Results: PLGA-PEI-PEG@NAT had a particle size of 150 nm, a positive surface charge, and a sustained-release effect. The MIC for F. Solani was 2 µg/mL. A cytotoxicity test and ocular irritation test showed that PLGA-PEI-PEG@NAT and Gel@PLGA-PEI-PEG@NAT had good biocompatibility and no obvious irritation for rabbit corneas. Penetration experiments confirmed that PLGA-PEI-PEG@NAT can successfully enter corneal epithelial cells and through the cornea to enter the anterior chamber. Compared with NAT ophthalmic suspension, Gel@PLGA-PEI-PEG@NAT had stronger cornea permeation at the same concentration. The therapeutic effect and precorneal retention ability of the NAT ophthalmic suspension and Gel@PLGA-PEI-PEG@NAT on the fungal keratitis rabbit model were compared. Gel@PLGA-PEI-PEG@NAT achieved a better therapeutic effect at a lower drug concentration, and its eye surface retention time was significantly longer than that of the NAT ophthalmic suspension. Conclusion: Gel@PLGA-PEI-PEG@NAT was shown to be a safe and effective nanodrug delivery system for NAT. It has great potential to improve the cure rate of fungal keratitis, reduce the administration frequency during the treatment process, and improve patient compliance.
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Nanopartículas , Natamicina , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Fusarium , Hidrogéis , Nanopartículas/química , Natamicina/farmacologia , Natamicina/uso terapêutico , Polietilenoglicóis/química , Polímeros/química , CoelhosRESUMO
Chronic pain, such as persistent inflammatory pain, remains a public health problem that has no effective treatment at present. Bromodomain-containing protein 4 (BRD4) inhibition, induced by JQ1 injection or BRD4 knockdown, has been used to attenuate inflammatory pain; However, it remains elusive whether BRD4 aggravates inflammatory pain by regulating inflammasome. Western blot and immunofluorescence staining showed that BRD4 expression increased after administration of complete Freund's adjuvant (CFA) and reached its peak on day 3. Immunofluorescence staining showed that BRD4 was mainly colocalized with NeuN-positive neurons in the spinal cord, which was accompanied by upregulation of inflammasome component proteins, such as NLRP3, gasdermin D, and caspase-1. JQ1 was intrathecally injected into mice 1 h before CFA administration, and the mechanical and thermal hyperalgesia levels were measured on days 1, 3, and 7 after CFA administration. CFA-induced inflammatory pain, paw inflammation, and swelling were attenuated by pre-treatment with JQ1. To our knowledge, this study was the first to prove that NLRP3 inflammasome-induced neuronal pyroptosis participates in inflammatory pain. BRD4 inhibition decreased the expression of pyroptosis-related proteins by inhibiting the activation of NF-κB signaling pathway, both in vivo and in vitro. Taken together, BRD4 inhibition exerted analgesic and anti-inflammatory effects against inflammatory pain by inhibiting NF-κB and inflammasome activation, which protected neural cells from pyroptosis.
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Azepinas/farmacologia , Inflamassomos/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Dor/tratamento farmacológico , Piroptose/efeitos dos fármacos , Fatores de Transcrição/antagonistas & inibidores , Triazóis/farmacologia , Animais , Linhagem Celular , Modelos Animais de Doenças , Adjuvante de Freund/administração & dosagem , Hiperalgesia/tratamento farmacológico , Inflamação/fisiopatologia , Injeções Espinhais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas Nucleares/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismoRESUMO
BACKGROUND: Gastric cancer is the fifth most common malignancy worldwide. In early stages, no obvious symptoms are usually observed in gastric cancer patients, and it is especially hard to distinguish gastric cancer from benign gastric diseases, resulting in delayed diagnosis and poor prognosis. Common biomarkers of gastric cancer, such as CEA and CA19-9, are also elevated in benign diseases. There is an urgent need to develop a convenient and reliable biomarker for differentiating between gastric cancer and benign gastric diseases. METHODS: This study retrospectively analyzed the data of 126 patients, including 73 gastric cancer patients and 53 benign gastric disease patients. Patient characteristics collected for analysis included age, gender, laboratory data, and clinical staging. Unpaired t-test was used to check the difference of cholinesterase level between the gastric cancer group and the benign gastric disease group. Kruskal Wallis H test and Mann-Whitney U test were used to check the difference of cholinesterase level among different stage groups. Receiver operating characteristic (ROC) curve was used to assess whether cholinesterase level can be used as a biomarker for differentiating between gastric cancer and benign gastric diseases. RESULTS: Serum cholinesterase level was decreased significantly in the gastric cancer group in comparison to that of the benign gastric disease group (p < 0.001). In addition, cholinesterase level of stage IV patients was significantly lower than stage I patients. ROC curve analysis revealed that with a cutoff of 5,969.00 U/L, cholinesterase level showed an area under the curve of 0.819 (95% CI 0.732 - 0.905, p < 0.001) in differentiating between gastric cancer and benign gastric diseases. No significant difference in the levels of CEA and CA19-9 was observed between gastric cancer patients and benign gastric disease patients. CONCLUSIONS: This study indicated that serum cholinesterase level could be considered as a potential biomarker for differentiating between gastric cancer and benign gastric diseases.
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Neoplasias Gástricas , Biomarcadores Tumorais , Antígeno CA-19-9 , Antígeno Carcinoembrionário , Colinesterases , Diagnóstico Diferencial , Humanos , Curva ROC , Estudos Retrospectivos , Neoplasias Gástricas/diagnósticoRESUMO
Activation of cyclic GMP-AMP synthase (cGAS) through sensing cytosolic double stranded DNA (dsDNA) plays a pivotal role in innate immunity against exogenous infection as well as cellular regulation under stress. Aberrant activation of cGAS induced by self-DNA is related to autoimmune diseases. cGAS accumulates at chromosomes during mitosis or spontaneously in the nucleus. Binding of cGAS to the nucleosome competitively attenuates the dsDNA-mediated cGAS activation, but the molecular mechanism of the attenuation is still poorly understood. Here, we report two cryo-electron microscopy structures of cGAS-nucleosome complexes. The structures reveal that cGAS interacts with the nucleosome as a monomer, forming 1:1 and 2:2 complexes, respectively. cGAS contacts the nucleosomal acidic patch formed by the H2A-H2B heterodimer through the dsDNA-binding site B in both complexes, and could interact with the DNA from the other symmetrically placed nucleosome via the dsDNA-binding site C in the 2:2 complex. The bound nucleosome inhibits the activation of cGAS through blocking the interaction of cGAS with ligand dsDNA and disrupting cGAS dimerization. R236A or R255A mutation of cGAS impairs the binding between cGAS and the nucleosome, and largely relieves the nucleosome-mediated inhibition of cGAS activity. Our study provides structural insights into the inhibition of cGAS activity by the nucleosome, and advances the understanding of the mechanism by which hosts avoid the autoimmune attack caused by cGAS.
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Nucleossomos/ultraestrutura , Nucleotidiltransferases/química , Nucleotidiltransferases/ultraestrutura , Sítios de Ligação , Microscopia Crioeletrônica , DNA/metabolismo , Histonas/metabolismo , Humanos , Modelos Moleculares , Nucleossomos/metabolismo , Nucleotidiltransferases/antagonistas & inibidores , Nucleotidiltransferases/metabolismo , Multimerização ProteicaRESUMO
BACKGROUND: Peripherally inserted central catheters (PICCs) has become increasingly popular in clinical practice because of the ease and safety of insertion and lower cost-effectiveness. The precise incidence and risk of PICC-related venous thrombosis is important to be verified in the context of growing PICC use and an understanding of the risk of venous thrombosis is an important cost and patient safety question. METHOD: We will search seven electronic databases including the Cochrane Library, MEDLINE, EMBASE, Chinese BioMedical Database, China National Knowledge Infrastructure, Chinese VIP and Wangfang Database regardless of publication date or language. All studies with prognostic factor analysis will be included if they recruited participants with PICC. Primary outcomes will include venous thrombosis. The risk of bias will be assessed by 2 authors using quality in prognostic studies tool. If possible, a meta-analysis in fixed or random effects model will be conducted by R-3.5.1 software, otherwise a narrative synthesis will ensue focusing on prognostic factors. The confidence in cumulative evidence will be assessed by Based on the Grading of Recommendations Assessment, Development and Evaluation. RESULTS: The aim of this study is to retrieve, appraise and summarize the clinical evidence of risk assessment for PICC-related venous thrombosis. CONCLUSIONS: This study will assess the precise incidence and risk of venous thrombosis in patients with PICC and provide references for establishing relevant assessment tools. ETHICS AND DISSEMINATION: This study is a protocol for systematic review and meta-analysis of prognostic factors for venous thrombosis in PICC patients. This review will be published in a journal and disseminated in print by peer-review.
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Cateterismo Periférico/efeitos adversos , Projetos de Pesquisa , Trombose Venosa/etiologia , Humanos , Prognóstico , Medição de Risco , Fatores de Risco , Metanálise como AssuntoRESUMO
Global emergencies caused by the severe acute respiratory syndrome coronavirus (SARS-CoV), Middle-East respiratory syndrome coronavirus (MERS-CoV) and SARS-CoV-2 significantly endanger human health. The spike (S) glycoprotein is the key antigen and its conserved S2 subunit contributes to viral entry by mediating host-viral membrane fusion. However, structural information of the post-fusion S2 from these highly pathogenic human-infecting coronaviruses is still lacking. We used single-particle cryo-electron microscopy to show that the post-fusion SARS-CoV S2 forms a further rotated HR1-HR2 six-helix bundle and a tightly bound linker region upstream of the HR2 motif. The structures of pre- and post-fusion SARS-CoV S glycoprotein dramatically differ, resembling that of the Mouse hepatitis virus (MHV) and other class I viral fusion proteins. This structure suggests potential targets for the development of vaccines and therapies against a wide range of SARS-like coronaviruses.
Assuntos
Betacoronavirus/química , Betacoronavirus/fisiologia , Glicoproteína da Espícula de Coronavírus/química , Motivos de Aminoácidos , COVID-19 , Coronavirus/química , Coronavirus/classificação , Infecções por Coronavirus/virologia , Microscopia Crioeletrônica , Humanos , Fusão de Membrana , Modelos Moleculares , Pandemias , Pneumonia Viral/virologia , Conformação Proteica , Multimerização Proteica , SARS-CoV-2 , Internalização do VírusRESUMO
BACKGROUND: MicroRNA-125b (miR-125b) is downregulated in human cutaneous squamous cell carcinoma (CSCC). However, its function in CSCC has yet to be extensively explored. Here, we analyze the relationship between signal transducer and activator of transcription 3 (STAT3) and miR-125b in CSCC. METHODS: Western blotting and quantitative RT-PCR were used to determine the expression of the miR-125b-STAT3 axis in human CSCC tissues and cell lines. The direct regulatory effect of miR-125b on STAT3 expression was assessed using a luciferase reporter gene assay and RNA immunoprecipitation assay. The MTT assay and flow cytometry were used to determine the role of the miR-125b-STAT3 axis in CSCC cell proliferation and apoptosis. RESULTS: MiR-125b expression levels were significantly lower in CSCC cell lines and tissues than in normal cell lines and tissues. STAT3 was identified as the direct target of miR-125b. Upregulation of miR-125b and downregulation of STAT3 suppressed cell proliferation and promoted cell apoptosis. Cyclin D1 and Bcl2 were identified as the downstream targets of the miR-125-STAT3 axis. CONCLUSIONS: Our findings indicate that miR-125b acts as a tumor suppressor in CSCC by targeting the STAT3 pathway. This observation increases our understanding of the molecular mechanisms of CSCC. Therapies aimed at activating miR-125b or inhibiting STAT3 signaling should be explored as potential treatments for CSCC.