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INTRODUCTION: Triple-negative breast cancer (TNBC) is the primary cause of breast cancer-induced death in women. Literature has confirmed the benefits of Salidroside (Sal) in treating TNBC. However, the study about potential therapeutic targets and mechanisms of Sal-anchored TNBC remains limited. OBJECTIVE: This study was designed to explore the main targets and potential mechanisms of Sal against TNBC. METHODS: Network pharmacology, bioinformatics, and machine learning algorithm strategies were integrated to examine the role, potential targets, and mechanisms of the Sal act in TNBC. MDA-MB-231 cells and tumor-bearing nude mice were chosen for in vitro and in vivo experimentation. Cell viability and cytotoxicity were determined using CCK-8, LDH test, and Calcein-AM/PI staining. Antioxidant defense, lipid peroxidation, and iron metabolism were explored using glutathione, glutathione peroxidase, malondialdehyde (MDA), C11-BODIPY 581/591 probe, and FerroOrange dye. Glutathione peroxidase 4 (GPX4) or stearoyl-CoA desaturase 1 (SCD1) overexpression or nuclear receptor co-activator 4 (NCOA4) deficiency was performed to demonstrate the mechanism of Sal on TNBC. RESULTS: The prediction results confirmed that 22 ferroptosis-related genes were identified in Sal and TNBC, revealing that the potential mechanism of the Sal act on TNBC was linked with ferroptosis. Besides, these genes were mainly involved in the mTOR, PI3K/AKT, and autophagy signaling pathway by functional enrichment analysis. The in vitro validation results confirmed that Sal inhibited TNBC cell proliferation by modulating ferroptosis via elevation of intracellular Fe2+ and lipid peroxidation. Mechanistically, Sal sensitized TNBC cells to ferroptosis by inhibiting the PI3K/AKT/mTOR axis, thereby suppressing SCD1-mediated lipogenesis of monounsaturated fatty acids to induce lipid peroxidation, additionally facilitating NCOA4-mediated ferritinophagy to increase intracellular Fe2+ content. The GPX4 or SCD1 overexpression or NCOA4 deficiency results further supported our mechanistic studies. In vivo experimentation confirmed that Sal is vital for slowing down tumor growth by inducing ferroptosis. CONCLUSIONS: Overall, this study elucidates TNBC pathogenesis closely linked to ferroptosis and identifies potential biomarkers in TNBC. Meanwhile, the study elucidates that Sal sensitizes TNBC to ferroptosis by SCD1-mediated lipogenesis and NCOA4-mediated ferritinophagy, regulated by PI3K/AKT/mTOR signaling pathways. Our findings provide a theoretical basis for applying Sal to treat TNBC.
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Introduction: Accurate identification of the etiology of orthopedic infection is very important for correct and timely clinical management, but it has been poorly studied. In the current study we explored the association of multiple bacterial pathogens with orthopedic infection. Methods: Hospitalized orthopedic patients were enrolled in a rural hospital in Qingdao, China. Wound or exudate swab samples were collected and tested for twelve bacterial pathogens with both culture and multiplex real time PCR. Results and discussion: A total of 349 hospitalized orthopedic patients were enrolled including 193 cases presenting infection manifestations upon admission and 156 with no sign of infection. Orthopedic infection patients were mainly male (72.5%) with more lengthy hospital stay (median 15 days). At least one pathogen was detected in 42.5% (82/193) of patients with infection while 7.1% (11/156) in the patients without infection (P < 0.001). S. aureus was the most prevalent causative pathogen (15.5%). Quantity dependent pathogen association with infection was observed, particularly for P. aeruginosa and K. pneumoniae, possibly indicating subclinical infection. Most of the patients with detected pathogens had a previous history of orthopedic surgery (odds ratio 2.8, P = 0.038). Pathogen specific clinical manifestations were characterized. Multiplex qPCR, because of its high sensitivity, superior specificity, and powerful quantification could be utilized in combination with culture to guide antimicrobial therapy and track the progression of orthopedic infection during treatment.
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Reação em Cadeia da Polimerase Multiplex , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , China/epidemiologia , Adulto , Bactérias/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Infecções Bacterianas/microbiologia , Infecções Bacterianas/diagnóstico , Hospitalização , Idoso de 80 Anos ou mais , Reação em Cadeia da Polimerase em Tempo Real , Hospitais RuraisRESUMO
Introduction: Clinical significance of coagulase-negative staphylococci (CoNS) has been gradually acknowledged in both healthcare and clinical research, but approaches for their precise discrimination at the species level remain scarce. The current study aimed to evaluate the association of CoNS with orthopedic infections, where accurate and prompt identification of etiology is crucial for appropriate diagnosis and treatment decision-making. Methods: A 16S rRNA-based quantitative PCR (qPCR) assay was developed for the detection of Staphylococcus genus and two panels of 3-plex qPCR assays for further differentiation of six CoNS species with remarkable clinical significance, including S. epidermidis, S. haemolyticus, S. simulans, S. hominis, S. capitis, and S. caprae. All the assays exhibited excellent analytical performance. ΔCq (quantification cycle) between 16S rRNA and CoNS species-specific targets was established to determine the primary CoNS. These methods were applied to detect CoNS in wound samples from orthopedic patients with and without infection. Results and discussion: Overall, CoNS were detected in 17.8% (21/118) of patients with clinically suspected infection and in 9.8% (12/123) of patients without any infection symptom (p < 0.05). Moreover, the association with infection was found to be bacterial quantity dependent. S. epidermidis was identified as the predominant species, followed by S. simulans, S. haemolyticus, and S. hominis. Male sex, open injury, trauma, and lower extremity were determined as risk factors for CoNS infections. CoNS-positive patients had significantly longer hospitalization duration (20 days (15, 33) versus 13 days (7, 22) for Staphylococcus-negative patients, p = 0.003), which could be a considerable burden for healthcare and individual patients. Considering the complex characteristics and devastating consequences of orthopedic infections, further expanding the detection scope for CoNS may be pursued to better understand the etiology of orthopedic infections and to improve therapeutic strategies.
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A disintegrin and metalloprotease 17 (ADAM17) is a membrane-tethered protease that triggers multiple signaling pathways. It releases active forms of the primary inflammatory cytokine tumor necrosis factor (TNF) and cancer-implicated epidermal growth factor (EGF) family growth factors. iRhom2, a rhomboid-like, membrane-embedded pseudoprotease, is an essential cofactor of ADAM17. Here, we present cryoelectron microscopy (cryo-EM) structures of the human ADAM17/iRhom2 complex in both inactive and active states. These reveal three regulatory mechanisms. First, exploiting the rhomboid-like hallmark of TMD recognition, iRhom2 interacts with the ADAM17 TMD to promote ADAM17 trafficking and enzyme maturation. Second, a unique iRhom2 extracellular domain unexpectedly retains the cleaved ADAM17 inhibitory prodomain, safeguarding against premature activation and dysregulated proteolysis. Finally, loss of the prodomain from the complex mobilizes the ADAM17 protease domain, contributing to its ability to engage substrates. Our results reveal how a rhomboid-like pseudoprotease has been repurposed during evolution to regulate a potent membrane-tethered enzyme, ADAM17, ensuring the fidelity of inflammatory and growth factor signaling.
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Proteína ADAM17 , Microscopia Crioeletrônica , Transdução de Sinais , Proteína ADAM17/metabolismo , Proteína ADAM17/genética , Humanos , Células HEK293 , Proteínas de Transporte/metabolismo , Proteínas de Transporte/genética , Inflamação/metabolismo , Inflamação/genética , Proteólise , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/genética , Domínios Proteicos , Ligação Proteica , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Fator de Crescimento Epidérmico/metabolismo , Fator de Crescimento Epidérmico/genética , Peptídeos e Proteínas de Sinalização IntracelularRESUMO
The comorbidity of chronic pain and depression poses tremendous challenges for the treatment of either one because they exacerbate each other with unknown mechanisms. As the posterior insular cortex (PIC) integrates multiple somatosensory and emotional information and is implicated in either chronic pain or depression, we hypothesize that the PIC and its projections may contribute to the pathophysiology of comorbid chronic pain and depression. We show that PIC neurons were readily activated by mechanical, thermal, aversive, and stressful and appetitive stimulation in naive and neuropathic pain male mice subjected to spared nerve injury (SNI). Optogenetic activation of PIC neurons induced hyperalgesia and conditioned place aversion in naive mice, whereas inhibition of these neurons led to analgesia, conditioned place preference (CPP), and antidepressant effect in both naive and SNI mice. Combining neuronal tracing, optogenetics, and electrophysiological techniques, we found that the monosynaptic glutamatergic projections from the PIC to the basolateral amygdala (BLA) and the ventromedial nucleus (VM) of the thalamus mimicked PIC neurons in pain modulation in naive mice; in SNI mice, both projections were enhanced accompanied by hyperactivity of PIC, BLA, and VM neurons and inhibition of these projections led to analgesia, CPP, and antidepressant-like effect. The present study suggests that potentiation of the PICâBLA and PICâVM projections may be important pathophysiological bases for hyperalgesia and depression-like behavior in neuropathic pain and reversing the potentiation may be a promising therapeutic strategy for comorbid chronic pain and depression.
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Dor Crônica , Neuralgia , Camundongos , Masculino , Animais , Hiperalgesia , Dor Crônica/complicações , Depressão , Córtex Insular , Tonsila do Cerebelo/metabolismo , Neuralgia/metabolismo , Comorbidade , Tálamo , Antidepressivos/uso terapêuticoRESUMO
Neurons in the subthalamic nucleus (STN) become hyperactive following nerve injury and promote pain-related responses in mice. Considering that the anterior cingulate cortex (ACC) is involved in pain and emotion processing and projects to the STN, we hypothesize that ACC neurons may contribute to hyperactivity in STN neurons in chronic pain. In the present study, we showed that ACC neurons enhanced activity in response to noxious stimuli and to alterations in emotional states and became hyperactive in chronic pain state established by spared nerve injury of the sciatic nerve (SNI) in mice. In naïve mice, STN neurons were activated by noxious stimuli, but not by alterations in emotional states. Pain responses in STN neurons were attenuated in both naïve and SNI mice when ACC neurons were inhibited. Furthermore, optogenetic activation of the ACC-STN pathway induced bilateral hyperalgesia and depression-like behaviors in naive mice; conversely, inhibition of this pathway is sufficient to attenuate hyperalgesia and depression-like behaviors in SNI mice and naïve mice subjected to stimulation of STN neurons. Finally, mitigation of pain-like and depression-like behaviors in SNI mice by inhibition of the ACC-STN projection was eliminated by activation of STN neurons. Our results demonstrate that hyperactivity in the ACC-STN pathway may be an important pathophysiology in comorbid chronic pain and depression. Thus, the ACC-STN pathway may be an intervention target for the treatment of the comorbid chronic pain and depression.
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Dor Crônica , Camundongos , Masculino , Animais , Giro do Cíngulo/fisiologia , Hiperalgesia , Depressão , Neurônios/fisiologiaRESUMO
Impaired macroautophagy/autophagy flux has been implicated in the treatment of prostate cancer (PCa). However, the mechanism underlying autophagy dysregulation in PCa remains unknown. In the current study, we investigated the role of diacylglycerol acyltransferases 1 (DGAT1) and its potential effects on cellular energy homeostasis and autophagy flux in PCa. The results of immunohistochemical staining suggested that DGAT1 expression was positively corrected with tumor stage and node metastasis, indicating DGAT1 is an important factor involved in the development and progression of PCa. Furthermore, targeting DGAT1 remarkably inhibited cell proliferation in vitro and suppressed PCa growth in xenograft models by triggering severe oxidative stress and subsequently autophagy flux blockage. Mechanically, DGAT1 promoted PCa progression by maintaining cellular energy homeostasis, preserving mitochondrial function, protecting against reactive oxygen species, and subsequently promoting autophagy flux via regulating lipid droplet formation. Moreover, we found that fenofibrate exhibits as an upstream regulator of DGAT1. Fenofibrate performed its anti-PCa effect involved the aforementioned mechanisms, and partially dependent on the regulation of DGAT1. Collectively. These findings indicate that DGAT1 regulates PCa lipid droplets formation and is essential for PCa progression. Targeting DGAT1 might be a promising method to control the development and progression of PCa. Schematic representation of DGAT1 affects autophagy flux by regulating lipid homeostasis and maintaining mitochondrial function in prostate cancer (PCa). PCa is characterized up-regulation of DGAT1, leading to the translocation of free fatty acids into lipid droplets, thereby preventing PCa cell from lipotoxicity. Inhibition of DGAT1 suppresses growth of PCa by inducing oxidative stress and subsequently autophagy flux blockage. Further, the current results revealed that fenofibrate exhibits as an upstream regulator of DGAT1, and fenofibrate plays an anti-PCa role partially dependent on the regulation of DGAT1, suggesting a potential therapeutic approach to ameliorate this refractory tumor.
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Fenofibrato , Neoplasias da Próstata , Humanos , Masculino , Autofagia , Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Fenofibrato/metabolismo , Fenofibrato/farmacologia , Fenofibrato/uso terapêutico , Estresse Oxidativo , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismoRESUMO
Excessive self-grooming is an important behavioral phenotype of the stress response in rodents. Elucidating the neural circuit that regulates stress-induced self-grooming may suggest potential treatment to prevent maladaptation to stress that is implicated in emotional disorders. Stimulation of the subthalamic nucleus (STN) has been found to induce strong self-grooming. In this study we investigated the role of the STN and a related neural circuit in mouse stress-related self-grooming. Body-restraint and foot-shock stress-induced self-grooming models were established in mice. We showed that both body restraint and foot shock markedly increased the expression of c-Fos in neurons in the STN and lateral parabrachial nucleus (LPB). Consistent with this, the activity of STN neurons and LPB glutamatergic (Glu) neurons, as assessed with fiber photometry recording, was dramatically elevated during self-grooming in the stressed mice. Using whole-cell patch-clamp recordings in parasagittal brain slices, we identified a monosynaptic projection from STN neurons to LPB Glu neurons that regulates stress-induced self-grooming in mice. Enhanced self-grooming induced by optogenetic activation of the STN-LPB Glu pathway was attenuated by treatment with fluoxetine (18 mg·kg-1·d-1, p.o., for 2 weeks) or in the presence of a cage mate. Furthermore, optogenetic inhibition of the STN-LPB pathway attenuated stress-related but not natural self-grooming. Taken together, these results suggest that the STN-LPB pathway regulates the acute stress response and is a potential target for intervention in stress-related emotional disorders.
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Núcleo Subtalâmico , Camundongos , Animais , Asseio Animal , Núcleo Subtalâmico/fisiologia , Neurônios/fisiologiaRESUMO
BACKGROUND: Central pontine myelinolysis (CPM) is a rare demyelinating disorder caused by the loss of myelin in the center of the basis pontis. CPM typically occurs with rapid correction of severe chronic hyponatremia and subsequent disturbances in serum osmolality. Although hyperglycaemia is recognized as a pathogenetic factor in serum osmolality fluctuations, CPM is rarely seen in the context of diabetes. CASE PRESENTATION: A 66-year-old Chinese male presented with a history of gait imbalance, mild slurred speech and dysphagia for two weeks. MRI showed the mass lesions in the brainstem, and laboratory examinations showed high blood glucose and HbA1c, as well as increased serum osmolality. The patient was diagnosed with CPM secondary to hyperosmolar hyperglyceamia and received insulin treatment as well as supportive therapy. After six weeks of followup, the patient had fully recovered to a normal state. CONCLUSION: CPM is a potentially fatal neurological condition and can occur in uncontrolled diabetes mellitus. Early diagnosis and timely treatment are crucial for improving the prognosis.
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Hiperglicemia , Hiponatremia , Mielinólise Central da Ponte , Masculino , Humanos , Idoso , Mielinólise Central da Ponte/diagnóstico por imagem , Mielinólise Central da Ponte/etiologia , Hiperglicemia/complicações , Imageamento por Ressonância MagnéticaRESUMO
To improve the effectiveness of envir onmental management of watersheds and improve the environmental management mechanism of cross-administrative watersheds, we develop a neoliberal framework for action using incentives, examine the cooperative strategies of local governments in watershed treatment and people-oriented environmental protection under central government subsidies, and analyze the cost effectiveness of multiple strategies in a dynamic perspective, and we have the following important findings: (1) Compared to vertical ecological compensation, the introduction of horizontal cost-sharing contracts is more effective in enhancing inter-local cooperative environmental governance. (2) When the marginal benefit of the downstream local government is greater than half of the upstream marginal benefit, the upstream local government's pollution control investment and the effect of pollution control are improved, and the Pareto improvement of the environmental governance benefit of the watershed is realized, i.e., the cost-sharing contract driven by the downstream can achieve a win-win situation for both environmental and government governance benefits. (3) When the marginal benefit of downstream environmental advocacy is between 0.5 and 1.5 times the marginal benefit of upstream government, the cost-sharing contract is more effective in improving downstream benefits. Conversely, when the marginal benefit of downstream is greater than 1.5 times, the marginal benefit of upstream, the more effective the cost-sharing contract is in improving the marginal benefit of downstream. The results of the study provide useful insights for the government to develop reasonable pollution management cooperation mechanisms to improve environmental management performance and thus enhance the sustainable development of the watershed.
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Conservação dos Recursos Naturais , Política Ambiental , Humanos , Poluição Ambiental/prevenção & controle , Governo , Governo Local , ChinaRESUMO
In this paper, the element nitrogen (N) is used to partially replace the element nickel (Ni) in flux-cored wire. A 44%Ni-24%Cr-0.18N nitrogen-containing low-nickel flux-cored wire with excellent corrosion resistance is prepared. The corrosion behavior of nitrogen-containing low-nickel weld cladding and Inconel 625 weld cladding in 40 KCl + 60 MgCl2 (wt%) molten salt at 900 °C is studied. The results show that the selective dissolution of Cr occurs in both weld claddings. The corrosion resistance of the 44%Ni-24%Cr-0.18N nitrogen-containing low-nickel weld cladding is better than that of the Inconel 625 weld cladding. The reason is that added N can react with H+ in molten salt to generate NH4+, remove corrosive impurities of MgOH+ in molten salt and change the corrosion environment. N preferentially combines with Cr to form Cr2N, reduces the diffusion precipitation of Cr and improves the corrosion resistance.
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The basal ganglia including the subthalamic nucleus (STN) and substantia nigra pars reticulata (SNr) are involved in pain-related responses, but how they regulate pain processing remains unknown. Here, we identify a pathway, consisting of GABAergic neurons in the SNr (SNrGABA) and glutamatergic neurons in the STN (STNGlu) and the lateral parabrachial nucleus (LPBGlu), that modulates acute and persistent pain states in both male and female mice. The activity of STN neurons was enhanced in acute and persistent pain states. This enhancement was accompanied by hypoactivity in SNrGABA neurons and strengthening of the STN-LPB glutamatergic projection. Reversing the dysfunction in the SNrGABA-STNGlu-LPBGlu pathway attenuated activity of LPBGlu neurons and mitigated pain-like behaviors. Therefore, the SNrGABA-STNGlu-LPBGlu pathway regulates pathological pain and is a potential target for pain management.
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Neurônios GABAérgicos , Substância Negra , Masculino , Feminino , Camundongos , Animais , Substância Negra/metabolismo , Estimulação Elétrica , Neurônios GABAérgicos/metabolismo , Ácido gama-Aminobutírico/metabolismo , Dor/metabolismoRESUMO
Purpose: To study the underlying molecular mechanisms of p53 in the mitochondrial dysfunction and the pathogenesis of Parkinson's disease (PD), and provide a potential therapeutic target for PD treatment.Methods: We review the contributions of p53 to mitochondrial changes leading to apoptosis and the subsequent degeneration of dopaminergic neurons in PD.Results: P53 is a multifunctional protein implicated in the regulation of diverse cellular processes via transcription-dependent and transcription-independent mechanisms. Mitochondria are vital subcellular organelles for that maintain cellular function, and mitochondrial defect and impairment are primary causes of dopaminergic neuron degeneration in PD. Increasing evidence has revealed that mitochondrial dysfunction-associated dopaminergic neuron degeneration is tightly regulated by p53 in PD pathogenesis. Neurodegenerative stress triggers p53 activation, which induces mitochondrial changes, including transmembrane permeability, reactive oxygen species production, Ca2+ overload, electron transport chain defects and other dynamic alterations, and these changes contribute to neurodegeneration and are linked closely with PD occurrence and development. P53 inhibition has been shown to attenuate mitochondrial dysfunction and protect dopaminergic neurons from degeneration under conditions of neurodegenerative stress.Conclusions: p53 appears to be a potential target for neuroprotective therapy of PD.
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This study aims to understand the potential relationship between water vulnerability and corporate financial performance for listed companies in China. Studies have argued that water risk has begun to affect the sustainability of firms, but few studies have included water conditions in the research framework to examine whether and how water conditions have a direct impact on firms. In addition, studies on environment governance have emphasized the impact of government environmental regulation on firms. This study focuses on both regulation and government investments that have been previously neglected. Using a sample of Chinese listed companies from 2016 to 2020, this paper uses pooled cross-sectional regressions with year and industry fixed effects to examine the effects of water vulnerability on corporate financial performance and analyze the mechanism of government water governance (which can be divided into water regulation and water investment) on the relationship between water vulnerability and corporate financial performance. This study finds that water vulnerability could negatively impact corporate financial performance, and water regulation can intensify but water investment couldn't significantly relieve the negative impact. The relationships above differ between SOEs and non-SOEs and water-intensive and non-water-intensive industries.
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Investimentos em Saúde , Organizações , China , Estudos Transversais , Governo , IndústriasRESUMO
OBJECTIVE: The present study was designed to explore endurable pressure intensity of different paranasal sinus mucosa in goats. METHOD: Mucosa commonly involved in maxillary sinus augmentation, including mucosa from maxillary sinus crest, maxillary sinus floor, and frontal sinus, were harvested in a computed tomography-guided manner. The obtained mucosa was then sectioned into square and irregular ones for maximum endurable pressure intensity determination and morphological observation, respectively. RESULTS: Thickness of paranasal sinus mucosa, as determined under morphological staining by an optical microscope with a graduated eyepiece, were calculated. And the results showed that the average thickness of maxillary sinus crest mucosa, floor mucosa, and frontal sinus mucosa in goats were 410.03 ± 65.97 µm, 461.33 ± 91.37 µm and 216.90 ± 46.47 µm, respectively. Significant differences between maxillary sinus crest and frontal sinus, maxillary sinus floor, and frontal sinus were observed (P < 0.05). Maximum endurable pressure intensity was determined by utilizing a self-made clamp device and the results revealed maximum endurable pressure intensity of maxillary sinus crest mucosa, floor mucosa and frontal sinus mucosa in goats were 260.08 ± 80.12Kpa, 306.90 ± 94.37Kpa and 121.72 ± 31.72Kpa, respectively. Also, a statistically significant difference was observed when comparing the endurable pressure intensity between maxillary sinus crest and frontal sinus, maxillary sinus floor, and frontal sinus (P < 0.05). Further correlation analysis also revealed a positive correlation between the thickness of mucosa of the maxillary sinus and frontal sinus and maximum endurable pressure intensity (P < 0.05). CONCLUSION: Mucosal thickness and maximum endurable pressure intensity of maxillary sinus crest and floor were larger than that of frontal sinus mucosa and a positive correlation between the thickness of mucosa and endurable pressure intensity was observed. Our results thus might provide an experimental basis and guidance for mucosa-related problems involved maxillary sinus augmentation.
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Levantamento do Assoalho do Seio Maxilar , Animais , Cabras , Humanos , Maxila , Seio Maxilar/anatomia & histologia , Seio Maxilar/diagnóstico por imagem , Mucosa , Levantamento do Assoalho do Seio Maxilar/métodosRESUMO
The voltage-gated ion channel activity depends on both activation (transition from the resting state to the open state) and inactivation. Inactivation is a self-restraint mechanism to limit ion conduction and is as crucial to membrane excitability as activation. Inactivation can occur when the channel is open or closed. Although open-state inactivation is well understood, the molecular basis of closed-state inactivation has remained elusive. We report cryo-EM structures of human KV4.2 channel complexes in inactivated, open, and closed states. Closed-state inactivation of KV4 involves an unprecedented symmetry breakdown for pore closure by only two of the four S4-S5 linkers, distinct from known mechanisms of open-state inactivation. We further capture KV4 in a putative resting state, revealing how voltage sensor movements control the pore. Moreover, our structures provide insights regarding channel modulation by KChIP2 and DPP6 auxiliary subunits. Our findings elucidate mechanisms of closed-state inactivation and voltage-dependent activation of the KV4 channel.
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Ativação do Canal Iônico , Canais de Potássio Shal , Humanos , Ativação do Canal Iônico/fisiologia , Cinética , Potenciais da Membrana/fisiologia , Canais de Potássio Shal/genética , Canais de Potássio Shal/metabolismoRESUMO
Depression is a common and serious mental disorder. Data on its pathogenesis remain unclear and the options of drug treatments are limited. Here, we explored the role of pyroptosis, a novel pro-inflammatory programmed cell death process, in depression as well as the anti-depression effects and mechanisms of salidroside (Sal), a bioactive extract from Rhodiola rosea L. We established a corticosterone (CORT)-induced or lipopolysaccharide (LPS)-induced mice in vivo, and CORT, or nigericin (NLRP3 agonist)-induced PC12 cells in vitro. Our findings demonstrated that Sal profoundly mediated CORT or LPS-induced depressive behavior and improved synaptic plasticity by upregulating the expression of brain-derived neurotrophic factor (BDNF) gene. The data showed upregulation of proteins associated with NLRP3-mediated pyroptosis, including NLRP3, cleaved Caspase-1, IL-1ß, IL-18, and cleaved GSDMD. The molecular docking simulation predicted that Sal would interact with P2X7 of the P2X7/NF-κB/NLRP3 signaling pathway. In addition, our findings showed that the NLRP3-mediated pyroptosis was regulated by P2X7/NF-κB/NLRP3 signaling pathway. Interestingly, Sal was shown to ameliorate depression via suppression of the P2X7/NF-κB/NLRP3 mediated pyroptosis, and rescued nigericin-induced pyroptosis in the PC12 cells. Besides, knock down of the NLRP3 gene by siRNA markedly increased the inhibitory effects of Sal on pyroptosis and proinflammatory responses. Taken together, our findings demonstrated that pyroptosis plays a crucial role in depression, and Sal ameliorates depression by suppressing the P2X7/NF-κB/NLRP3-mediated pyroptosis. Thus, our study provides new insights into the potential treatment options for depression.
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High-density human activities have rapidly changed the pattern of urban land use/land cover (LULC), affecting the supply of urban ecosystem services (ESs). This poses a challenge to the balance of urban development and ecological protection, which may be more serious in ecologically fragile regions. This study identified key LULC change (LULCC) impacts on ESs in Ordos, an ecologically fragile region in Northwest China. The urbanization process of Ordos will continue in 2030 under the business-as-usual scenario due to its strategic positioning in the National Energy Base of China. The future LULC simulation results showed that developed land in eastern Ordos will continue to expand in 2030, and more forest and grassland will appear in western Ordos as a result of ecological restoration. The results of the InVEST model in calculating four important ESs showed that the ES supply in the densely populated areas (eastern Ordos) has declined, and more attention must be given to natural vegetation protection in the urbanization process. Although carbon storage in the western region has increased due to afforestation, this also reduces the water yield supply, which may exacerbate the water shortage in Ordos. Supported by this framework, more sustainable urban land use management can be undertaken to balance the conflict between ecological protection and urbanization. This will contribute to regional ecological health and sustainable urban development.