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The type-1 ryanodine receptor (RyR1) is an intracellular calcium (Ca(2+)) release channel required for skeletal muscle contraction. Here, we present cryo-EM reconstructions of RyR1 in multiple functional states revealing the structural basis of channel gating and ligand-dependent activation. Binding sites for the channel activators Ca(2+), ATP, and caffeine were identified at interdomain interfaces of the C-terminal domain. Either ATP or Ca(2+) alone induces conformational changes in the cytoplasmic assembly ("priming"), without pore dilation. In contrast, in the presence of all three activating ligands, high-resolution reconstructions of open and closed states of RyR1 were obtained from the same sample, enabling analyses of conformational changes associated with gating. Gating involves global conformational changes in the cytosolic assembly accompanied by local changes in the transmembrane domain, which include bending of the S6 transmembrane segment and consequent pore dilation, displacement, and deformation of the S4-S5 linker and conformational changes in the pseudo-voltage-sensor domain.
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Agonistas dos Canais de Cálcio/química , Ativação do Canal Iônico , Contração Muscular , Canal de Liberação de Cálcio do Receptor de Rianodina/química , Animais , Sítios de Ligação , Cafeína/química , Cálcio/química , Microscopia Crioeletrônica , Ligantes , Domínios Proteicos , Coelhos , Proteínas de Ligação a Tacrolimo/químicaRESUMO
S100A1, a small homodimeric EF-hand Ca2+-binding protein (~21 kDa), plays an important regulatory role in Ca2+ signaling pathways involved in various biological functions including Ca2+ cycling and contractile performance in skeletal and cardiac myocytes. One key target of the S100A1 interactome is the ryanodine receptor (RyR), a huge homotetrameric Ca2+ release channel (~2.3 MDa) of the sarcoplasmic reticulum. Here, we report cryoelectron microscopy structures of S100A1 bound to RyR1, the skeletal muscle isoform, in absence and presence of Ca2+. Ca2+-free apo-S100A1 binds beneath the bridging solenoid (BSol) and forms contacts with the junctional solenoid and the shell-core linker of RyR1. Upon Ca2+-binding, S100A1 undergoes a conformational change resulting in the exposure of the hydrophobic pocket known to serve as a major interaction site of S100A1. Through interactions of the hydrophobic pocket with RyR1, Ca2+-bound S100A1 intrudes deeper into the RyR1 structure beneath BSol than the apo-form and induces sideways motions of the C-terminal BSol region toward the adjacent RyR1 protomer resulting in tighter interprotomer contacts. Interestingly, the second hydrophobic pocket of the S100A1-dimer is largely exposed at the hydrophilic surface making it prone to interactions with the local environment, suggesting that S100A1 could be involved in forming larger heterocomplexes of RyRs with other protein partners. Since S100A1 interactions stabilizing BSol are implicated in the regulation of RyR-mediated Ca2+ release, the characterization of the S100A1 binding site conserved between RyR isoforms may provide the structural basis for the development of therapeutic strategies regarding treatments of RyR-related disorders.
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Cálcio , Microscopia Crioeletrônica , Canal de Liberação de Cálcio do Receptor de Rianodina , Proteínas S100 , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/química , Proteínas S100/metabolismo , Proteínas S100/química , Cálcio/metabolismo , Animais , Ligação Proteica , Sítios de Ligação , Modelos Moleculares , Conformação Proteica , HumanosRESUMO
Extinction of threat memory is a measure of behavioral flexibility. In the absence of additional reinforcement, the extinction of learned behaviors allows animals and humans to adapt to their changing environment. Extinction mechanisms and their therapeutic implications for maladaptive learning have been extensively studied. However, how aging affects extinction learning is much less understood. Using a rat model of olfactory threat extinction, we show that the extinction of olfactory threat memory is impaired in aged Sprague-Darley rats. Following extinction training, long-term depression (LTD) in the piriform cortex (PC) was inducible ex vivo in aged rats and was NMDA receptor (NMDAR)-independent. On the other hand, adult rats acquired successful olfactory threat extinction, and LTD was not inducible following extinction training. Neuronal cFos activation in the posterior PC correlated with learning and extinction performance in rats. NMDAR blockade either systemically or locally in the PC during extinction training prevented successful extinction in adult rats, following which NMDAR-dependent LTD became inducible ex vivo. This suggests that extinction learning employs NMDAR-dependent LTD mechanisms in the PC of adult rats, thus occluding further LTD induction ex vivo. The rescue of olfactory threat extinction in aged rats by D-cycloserine, a partial NMDAR agonist, suggests that the impairment in olfactory threat extinction of aged animals may relate to NMDAR hypofunctioning and a lack of NMDAR-dependent LTD. These findings are consistent with an age-related switch from NMDAR-dependent to NMDAR-independent LTD in the PC. Optimizing NMDAR function in sensory cortices may improve learning and flexible behavior in the aged population.
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Córtex Piriforme , Receptores de N-Metil-D-Aspartato , Humanos , Ratos , Animais , Idoso , Receptores de N-Metil-D-Aspartato/metabolismo , Depressão , Córtex Piriforme/metabolismo , Aprendizagem/fisiologia , Plasticidade Neuronal/fisiologiaRESUMO
In this study, a novel europium dual-ligand metal-organic gel (Eu-D-MOGs) with high-efficient anodic annihilation electrochemiluminescence (ECL) was synthesized as an ECL emitter to construct a biosensor for ultrasensitive detection of microRNA-221 (miR-221). Impressively, compared to the ECL signal of europium single-ligand metal-organic gels (Eu-S-MOGs), the ECL signal of Eu-D-MOGs was significantly improved since the two organic ligands could jointly replace the H2O and coordinate with Eu3+, which could remarkably reduce the nonradiative vibrational energy transfer caused by the coordination between H2O and Eu3+ with a high coordination demand. In addition, Eu-D-MOGs could be electrochemically oxidized to Eu-D-MOGsâ¢+ at 1.45 V and reduced to Eu-D-MOGsâ¢- at 0.65 V to achieve effective annihilation of ECL, which overcame the side reaction brought by the remaining emitters at negative potential. This benefited from the annihilation ECL performance of the central ion Eu3+ caused by its redox in the electrochemical process. Furthermore, the annihilation ECL signal of Eu3+ could be improved by sensitizing Eu3+ via the antenna effect. In addition, combined with the improved rolling circle amplification-assisted strand displacement amplification strategy (RCA-SDA), a sensitive biosensor was constructed for the sensitive detection of miR-221 with a low detection limit of 5.12 aM and could be successfully applied for the detection of miR-221 in the lysate of cancer cells. This strategy offered a unique approach to synthesizing metal-organic gels as ECL emitters without a coreactant for the construction of ECL biosensing platforms in biomarker detection and disease diagnosis.
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Técnicas Eletroquímicas , Eletrodos , Európio , Géis , Medições Luminescentes , MicroRNAs , Európio/química , MicroRNAs/análise , Técnicas Eletroquímicas/métodos , Ligantes , Géis/química , Técnicas Biossensoriais/métodos , Limite de Detecção , HumanosRESUMO
Liver fibrosis could progress to liver cirrhosis with several contributing factors, one being iron overload which triggers ferroptosis, a form of regulated cell death. Rifaximin, a non-absorbable antibiotic, has shown promise in mitigating fibrosis, primarily by modulating gut microbiota. This study investigated the effects and mechanisms of rifaximin on iron overload-related hepatic fibrosis and ferroptosis. In an iron overload-induced liver fibrosis model in mice and in ferric ammonium citrate (FAC)-stimulated primary hepatocytes, treatment with rifaximin showed significant therapeutic effects. Specifically, it ameliorated the processes of ferroptosis triggered by iron overload, reduced liver injury, and alleviated fibrosis. This was demonstrated by decreased iron accumulation in the liver, improved liver function, and reduced fibrotic area and collagen deposition. Rifaximin also modulated key proteins related to iron homeostasis and ferroptosis, including reduced expression of TFR1, a protein facilitating cellular iron uptake, and increased expression of Fpn and FTH, proteins involved in iron export and storage. In the context of oxidative stress, rifaximin treatment led to a decrease in lipid peroxidation, evidenced by reduced levels of reactive oxygen species (ROS) and malondialdehyde (MDA), and an increase in the reduced glutathione (GSH) and decrease in oxidized glutathione (GSSG). Notably, rifaximin's potential functions were associated with the TGF-ß pathway, evidenced by suppressed Tgfb1 protein levels and ratios of phosphorylated to total Smad2 and Smad3, whereas increased Smad7 phosphorylation. These findings indicate rifaximin's therapeutic potential in managing liver fibrosis by modulating the TGF-ß pathway and reducing iron overload-induced damage. Further research is required to confirm these results and explore their clinical implications.
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Ferroptose , Sobrecarga de Ferro , Animais , Camundongos , Rifaximina/efeitos adversos , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/metabolismo , Cirrose Hepática/metabolismo , Ferro/metabolismo , Fator de Crescimento Transformador betaRESUMO
BACKGROUND: High Neutrophil-to-Lymphocyte Ratio (NLR), Monocyte-to-Lymphocyte Ratio (MLR), Platelet-to-Lymphocyte Ratio (PLR) were associated with worse prognosis of patients with sepsis. In-hospital mortality has been reported to be higher in patients with coronary artery disease (CAD) and sepsis than those with sepsis alone. However, the relationship between NLR, MLR, PLR and mortality in septic patients with coronary artery disease (CAD) remains unclear. The study aimed to explore the association between NLR, MLR, PLR and 28-day all-cause mortality in septic patients with CAD. METHODS: We performed an observational cohort study of septic patients with CAD from the Medical Information Mart for Intensive Care (MIMIC)-IV database between 2008 and 2019. The patients were categorized by three group (Q1: low levels, Q2: medium levels, Q3: high levels) based on tertiles of NLR, MLR, and PLR. The associations between NLR, MLR, PLR and 28-day all-cause mortality were examined using the Cox proportional hazards model. Subsequently, we applied receiver operating characteristic (ROC) analysis for predicting 28-day mortality in septic patients with CAD by combining NLR, MLR and PLR with the modified sequential organ failure assessment (mSOFA) scores. RESULTS: Overall 1,175 septic patients with CAD were included in the study. Observed all-cause mortality rates in 28 days were 27.1%. Multivariate Cox proportional hazards regression analysis results showed that 28-day all-cause mortality of septic patients with CAD was significantly related to rising NLR levels (adjusted hazard ratio [aHR]: 1.02; 95% confidence interval [CI]: 1.01-1.02; P < 0.001), MLR levels (aHR: 1.29; 95%CI: 1.18-1.41; P < 0.001), and PLR levels (aHR: 1.0007; 95%CI: 1.0004-1.0011; P < 0.001). Meanwhile, the higher levels (Q3) group of NLR, MLR, and PLR also had a higher risk of 28-day all-cause mortality than the lower (Q1) group. The area under the ROC curve of NLR, MLR, PLR, and mSOFA score were 0.630 (95%CI 0.595-0.665), 0.611 (95%CI 0.576-0.646), 0.601 (95%CI 0.567-0.636) and 0.718 (95%CI 0.689-0.748), respectively. Combining NLR, MLR, and PLR with mSOFA scores may improve ability of predicting 28-day mortality (AUC: 0.737, 95%CI 0.709-0.766). CONCLUSION: Higher levels of NLR, MLR and PLR were associated with 28-day all-cause mortality in septic patients with CAD. Further investigation will be needed to improve understanding of the pathophysiology of this relationship.
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Plaquetas , Doença da Artéria Coronariana , Linfócitos , Monócitos , Neutrófilos , Sepse , Humanos , Masculino , Feminino , Sepse/mortalidade , Sepse/sangue , Estudos Retrospectivos , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/sangue , Idoso , Pessoa de Meia-Idade , Prognóstico , Bases de Dados Factuais , Curva ROC , Contagem de Linfócitos , Mortalidade Hospitalar , Contagem de PlaquetasRESUMO
Aging is associated with cognitive decline and memory loss in humans. In rats, aging-associated neuronal excitability changes and impairments in learning have been extensively studied in the hippocampus. Here, we investigated the roles of L-type calcium channels (LTCCs) in the rat piriform cortex (PC), in comparison with those of the hippocampus. We employed spatial and olfactory tasks that involve the hippocampus and PC. LTCC blocker nimodipine administration impaired spontaneous location recognition in adult rats (6-9 months). However, the same blocker rescued the spatial learning deficiency in aged rats (19-23 months). In an odor-associative learning task, infusions of nimodipine into either the PC or dorsal CA1 impaired the ability of adult rats to learn a positive odor association. Again, in contrast, nimodipine rescued odor associative learning in aged rats. Aged CA1 neurons had higher somatic expression of LTCC Cav1.2 subunits, exhibited larger afterhyperpolarization (AHP) and lower excitability compared with adult neurons. In contrast, PC neurons from aged rats showed higher excitability and no difference in AHP. Cav1.2 expression was similar in adult and aged PC somata, but relatively higher in PSD95- puncta in aged dendrites. Our data suggest unique features of aging-associated changes in LTCCs in the PC and hippocampus.
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Nimodipina , Córtex Piriforme , Humanos , Ratos , Animais , Idoso , Nimodipina/metabolismo , Córtex Piriforme/metabolismo , Células Piramidais/fisiologia , Hipocampo/fisiologia , Canais de Cálcio Tipo L/metabolismo , Envelhecimento/fisiologiaRESUMO
BACKGROUND: New technologies have brought about a new age of technology-enabled aids that can equip informal carers with the relevant resources for better care. These include but are not limited to facilitating access to healthcare providers, knowledge of caring for persons living with dementia, and sources of support for carers' well-being. This qualitative study explores barriers to using eHealth/mHealth platforms and perceived beneficial eHealth/mHealth platform features among informal carers of persons living with dementia. METHODS: An exploratory qualitative study design was employed. Semi-structured interviews were conducted among 29 informal carers of persons living with dementia in Singapore recruited via convenience and snowball sampling. The interviews were audio-recorded and transcribed verbatim. Thematic analysis was used to analyse the data. RESULTS: The participants in this study identified several barriers to using eHealth/mHealth platforms, including personal preference, apprehension, poor user experience and lack of skills. On the other hand, knowledge of dementia, caring for persons living with dementia and self-care, a list of resources, social support, location monitoring and alert systems, and the ability to manage appointments and transactions were valuable features for eHealth/mHealth platforms. CONCLUSIONS: Despite the underutilisation of eHealth/mHealth platforms, carers expressed a keen interest in using them if they are functional and capable of reducing their care burden. The findings from this study can contribute to developing content and features for eHealth/mHealth interventions aimed at lightening carers' burden in their day-to-day caring routine.
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Demência , Telemedicina , Humanos , Cuidadores , Pessoal de Saúde , Conhecimento , Demência/terapiaRESUMO
Roads are the fundamental elements of transportation, connecting cities and rural areas, as well as people's lives and work. They play a significant role in various areas such as map updates, economic development, tourism, and disaster management. The automatic extraction of road features from high-resolution remote sensing images has always been a hot and challenging topic in the field of remote sensing, and deep learning network models are widely used to extract roads from remote sensing images in recent years. In light of this, this paper systematically reviews and summarizes the deep-learning-based techniques for automatic road extraction from high-resolution remote sensing images. It reviews the application of deep learning network models in road extraction tasks and classifies these models into fully supervised learning, semi-supervised learning, and weakly supervised learning based on their use of labels. Finally, a summary and outlook of the current development of deep learning techniques in road extraction are provided.
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This paper delves into the problem of direct position determination (DPD) for non-Gaussian sources. Existing DPD algorithms are hindered by their high computational complexity from exhaustive grid searches and a disregard for the received signal characteristics by multiple nested arrays (MNAs). To address these issues, the paper proposes a novel DPD algorithm for non-Gaussian sources with MNAs: the Discrete Fourier Transform (DFT) and Taylor compensation algorithm. Initially, the fourth-order cumulant matrix of the received signal is computed, and the vectorizing method is applied. Subsequently, a computationally efficient DPD cost function is proposed by leveraging a normalized DFT matrix to reduce complexity. Finally, first-order Taylor compensation is utilized to enhance the accuracy of the localization results. The superiority of the proposed algorithm is demonstrated through numerical simulation results.
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BACKGROUND: Allergic asthma is largely dominated by Th2 lymphocytes. Micropeptides in Th2 cells and asthma remain unmasked. Here, we aimed to demonstrate a micropeptide, T-cell regulatory micropeptide (TREMP), in Th2 cell differentiation in asthma. METHODS: TREMP translated from lincR-PPP2R5C was validated using Western blotting and mass spectrometry. TREMP knockout mice were generated using CRISPR/Cas9. Coimmunoprecipitation revealed that TREMP targeted pyrroline-5-carboxylate reductase 1 (PYCR1), which was further explored in vitro and in vivo. The levels of TREMP and PYCR1 in Th2 cells from clinical samples were determined by flow cytometry. RESULTS: TREMP, encoded by lincR-PPP2R5C, was in the mitochondrion. The lentivirus encoding TREMP promoted Th2 cell differentiation. In contrast, Th2 differentiation was suppressed in TREMP-/- CD4+ T cells. In the HDM-induced model of allergic airway inflammation, TREMP was increased in pulmonary tissues. Allergic airway inflammation was relieved in TREMP-/- mice treated with HDM. Mechanistically, TREMP interacted with PYCR1, which regulated Th2 differentiation via glycolysis. Glycolysis was decreased in Th2 cells from TREMP-/- mice and PYCR1-/- mice. Similar to TREMP-/- mice, allergic airway inflammation was mitigated in HDM-challenged PYCR1-/- mice. Moreover, we measured TREMP and PYCR1 in asthma patients. And we found that, compared with those in healthy controls, the levels of TREMP and PYCR1 in Th2 cells were significantly increased in asthmatic patients. CONCLUSIONS: The micropeptide TREMP encoded by lincR-PPP2R5C promoted Th2 differentiation in allergic airway inflammation by interacting with PYCR1 and enhancing glycolysis. Our findings highlight the importance of neglected micropeptides from noncoding RNAs in allergic diseases.
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Braak has described the beginnings of Alzheimer's Disease as occurring in the locus coeruleus. Here we review these pretangle stages and relate their expression to recently described normal features of tau biology. We suggest pretangle tau depends on characteristics of locus coeruleus operation that promote tau condensates. We examine the timeline of pretangle and tangle appearance in locus coeruleus. We find catastrophic loss of locus coeruleus neurons is a late event. The strong relationship between locus coeruleus neuron number and human cognition underscores the utility of a focus on locus coeruleus. Promoting locus coeruleus health will benefit normal aging as well as aid in the prevention of dementia. Two animal models offering experimental approaches to understanding the functional change initiated by pretangles in locus coeruleus neurons are discussed.
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Envelhecimento/genética , Doença de Alzheimer/genética , Locus Cerúleo/metabolismo , Proteínas tau/metabolismo , Animais , HumanosRESUMO
Mutations in the lamin A/C gene (LMNA), which encodes A-type lamins, cause several diseases called laminopathies, the most common of which is dilated cardiomyopathy with muscular dystrophy. The role of Ca2+ regulation in these diseases remain poorly understood. We now show biochemical remodeling of the ryanodine receptor (RyR)/intracellular Ca2+ release channel in heart samples from human subjects with LMNA mutations, including protein kinase A-catalyzed phosphorylation, oxidation and depletion of the stabilizing subunit calstabin. In the LmnaH222P/H222P murine model of Emery-Dreifuss muscular dystrophy caused by LMNA mutation, we demonstrate an age-dependent biochemical remodeling of RyR2 in the heart and RyR1 in skeletal muscle. This RyR remodeling is associated with heart and skeletal muscle dysfunction. Defective heart and muscle function are ameliorated by treatment with a novel Rycal small molecule drug (S107) that fixes 'leaky' RyRs. SMAD3 phosphorylation is increased in hearts and diaphragms of LmnaH222P/H222P mice, which enhances NADPH oxidase binding to RyR channels, contributing to their oxidation. There is also increased generalized protein oxidation, increased calcium/calmodulin-dependent protein kinase II-catalyzed phosphorylation of RyRs and increased protein kinase A activity in these tissues. Our data show that RyR remodeling plays a role in cardiomyopathy and skeletal muscle dysfunction caused by LMNA mutation and identify these Ca2+ channels as a potential therapeutic target.
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Cardiomiopatias/patologia , Modelos Animais de Doenças , Coração/fisiopatologia , Lamina Tipo A/genética , Distrofias Musculares/patologia , Mutação , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Animais , Sinalização do Cálcio , Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Feminino , Homeostase , Humanos , Masculino , Camundongos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Distrofias Musculares/etiologia , Distrofias Musculares/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/genéticaRESUMO
Fine particulate matter (PM2.5) concentrations have decreased in the past decade. The adverse effects of acute PM2.5 exposure on respiratory diseases have been well recognized. To explore the long-term effects of PM2.5 exposure on chronic obstructive pulmonary disease (COPD), mice were exposed to PM2.5 for 7 days and rest for 21 days, followed by challenges with lipopolysaccharide (LPS) and porcine pancreatic elastase (PPE). Unexpectedly, PM2.5 exposure and rest alleviated the disease severity and airway inflammatory responses in COPD-like mice. Although acute PM2.5 exposure increased airway inflammation, rest for 21 days reversed the airway inflammatory responses, which was associated with the induction of inhibitory memory alveolar macrophages (AMs). Similarly, polycyclic aromatic hydrocarbons (PAHs) in PM2.5 exposure and rest decreased pulmonary inflammation, accompanied by inhibitory memory AMs. Once AMs were depleted, pulmonary inflammation was aggravated. PAHs in PM2.5 promoted the secretion of IL-33 from airway epithelial cells via the aryl hydrocarbon receptor (AhR)/ARNT pathway. High-throughput mRNA sequencing revealed that PM2.5 exposure and rest drastically changed the mRNA profiles in AMs, which was largely rescued in IL-33-/- mice. Collectively, our results indicate that PM2.5 may mitigate pulmonary inflammation, which is mediated by inhibitory trained AMs via IL-33 production from epithelial cells through the AhR/ARNT pathway. We provide the rationale that PM2.5 plays complicated roles in respiratory disease.
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Pneumonia , Doença Pulmonar Obstrutiva Crônica , Animais , Camundongos , Interleucina-33 , Macrófagos Alveolares/metabolismo , Material Particulado/toxicidade , Pneumonia/induzido quimicamente , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , SuínosRESUMO
The magnetic field gradient affects the improvement of sensitivity and magnetic field suppression ability of the spin-exchange relaxation-free co-magnetometer. This paper proposes a response model of a co-magnetometer considering magnetic field gradient based on state-space method. The effects of transverse and longitudinal magnetic field gradients on the system's scale factor, bandwidth and magnetic field response are analyzed. The analysis shows that transverse gradient affects the whole frequency band of system response, including steady-state and dynamic performance, while longitudinal gradient only affects steady-state response. With the increase of the gradient, the effect becomes more significant. The test results are in agreement with the theory, proving the accuracy of the theoretical analysis. The rotational sensitivity at 1 Hz decreases from 6.51 ×10-6 °/s/Hz1/2 to 5.05×10-5 °/s/Hz1/2 in the presence of a magnetic field gradient of -40 nT/cm, so the effect of the magnetic field gradient is critical. This work provides an accurate model for evaluating the effects of magnetic field gradients and provides a method for suppressing gradients using gradient coils, which are important for improving the sensitivity and accuracy of co-magnetometers.
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Cryptococcus neoformans (C. neoformans) is an important opportunistic fungal pathogen for pulmonary cryptococcosis. Previously, we demonstrated that CD146 mediated the adhesion of C. neoformans to the airway epithelium. CD146 is more than an adhesion molecule. In the present study, we aimed to explore the roles of CD146 in the inflammatory response in pulmonary cryptococcosis. CD146 was decreased in lung tissues from patients with pulmonary cryptococcosis. Similarly, C. neoformans reduced pulmonary CD146 expression in mice following intratracheal inoculation. To explore the pathological roles of CD146 reduction in pulmonary cryptococcosis, CD146 knockout (KO) mice were inoculated with C. neoformans via intratracheal instillation. CD146 deficiency aggravated C. neoformans infection, as evidenced by a shortened survival time and increased fungal burdens in the lung. Inflammatory type 2 cytokines (IL-4, IL-5, and TNF-α) and alternatively activated macrophages were increased in the pulmonary tissues of CD146 KO-infected mice. CD146 is expressed in immune cells (macrophages, etc.) and nonimmune cells, i.e., epithelial cells and endothelial cells. Bone marrow chimeric mice were established and infected with C. neoformans. CD146 deficiency in immune cells but not in nonimmune cells increased fungal burdens in the lung. Mechanistically, upon C. neoformans challenge, CD146 KO macrophages produced more neutrophil chemokine KC and inflammatory cytokine TNF-α. Meanwhile, CD146 KO macrophages decreased the fungicidity and production of reactive oxygen species. Collectively, C. neoformans infection decreased CD146 in pulmonary tissues, leading to inflammatory type 2 responses, while CD146 deficiency worsened pulmonary cryptococcosis.
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Criptococose , Cryptococcus neoformans , Animais , Camundongos , Antígeno CD146 , Citocinas , Células Endoteliais , Camundongos Knockout , Fator de Necrose Tumoral alfaRESUMO
Hepatic stellate cells (HSCs) and cancer-associated fibroblasts (CAFs) play critical roles in liver fibrosis and hepatocellular carcinoma (HCC). MyD88 controls the expression of several key modifier genes in liver tumorigenesis; however, whether and how MyD88 in myofibroblasts contributes to the development of fibrosis-associated liver cancer remains elusive. Here, we used an established hepatocarcinogenesis mouse model involving apparent liver fibrogenesis in which MyD88 was selectively depleted in myofibroblasts. Myofibroblast MyD88-deficient (Fib-MyD88 KO) mice developed significantly fewer and smaller liver tumor nodules. MyD88 deficiency in myofibroblasts attenuated liver fibrosis and aerobic glycolysis in hepatocellular carcinoma tissues. Mechanistically, MyD88 signaling in myofibroblasts increased the secretion of CCL20, which promoted aerobic glycolysis in cancer cells. This process was dependent on the CCR6 receptor and ERK/PKM2 signaling. Furthermore, liver tumor growth was greatly relieved when the mice were treated with a CCR6 inhibitor. Our data revealed a critical role for MyD88 in myofibroblasts in the promotion of hepatocellular carcinoma by affecting aerobic glycolysis in cancer cells and might provide a potential molecular therapeutic target for HCC. © 2021 The Pathological Society of Great Britain and Ireland.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Piruvato Quinase/metabolismo , Animais , Carcinogênese/patologia , Carcinoma Hepatocelular/patologia , Núcleo Celular , Glicólise , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Camundongos , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Miofibroblastos/metabolismoRESUMO
Synaptic behavior simulation in transistors based on MoS2 has been reported. MoS2 was utilized as the active layer to prepare ambipolar thin-film transistors. The excitatory postsynaptic current phenomenon was simulated, observing a gradual voltage decay following the removal of applied pulses, ultimately resulting in a response current slightly higher than the initial current. Subsequently, ±5 V voltages were separately applied for ten consecutive pulse voltage tests, revealing short-term potentiation and short-term depression behaviors. After 92 consecutive positive pulses, the device current transitioned from an initial value of 0.14 to 28.3 mA. Similarly, following 88 consecutive negative pulses, the device current changed, indicating long-term potentiation and long-term depression behaviors. We also employed a pair of continuous triangular wave pulses to evaluate paired-pulse facilitation behavior, observing that the response current of the second stimulus pulse was â¼1.2× greater than that of the first stimulus pulse. The advantages and prospects of using MoS2 as a material for thin-film transistors were thoroughly displayed.
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BACKGROUND: Positive aspects of caregiving are important coping resources for informal caregivers of persons with dementia (PWD). However, existing studies mostly focused on caregivers from western societies and less attention was paid to the potential cultural differences. This study aims to explore positive aspects of caregiving in the Asian context. METHODS: A qualitative methodology with semi-structured interviews was adopted. A total of 29 informal caregivers of PWD in Singapore were interviewed from Apr 2019 to Dec 2020. All the interviews were audio-recorded and transcribed verbatim for the analysis. Inductive thematic analysis was conducted. RESULTS: The results revealed a total of three major themes with 11 sub-themes including: 1) positive aspects within self (i.e., better understanding of dementia and caregiving, personal growth, role satisfaction, and improved awareness of self-care); 2) positive aspects between caregiver and PWD (i.e., chance to demonstrate filial piety towards PWD, happiness and positive attitudes of PWD, positive interactions with PWD, and closer relationships with PWD); and 3) positive aspects between caregiver and others (i.e., empathy towards other caregivers, befriending peers, and sharing dementia and caregiving knowledge with others). DISCUSSION: Findings from this study improved our understanding on positive aspects of caregiving among informal caregivers of PWD in the Asian context. In addition to similar themes across cultures such as personal growth, our study identified a few unique themes like improved awareness of self-care and chances to demonstrate filial piety. For future studies targeting Asian caregivers, it is necessary to include these cultural-specific positive aspects of caregiving.
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Cuidadores , Demência , Humanos , Demência/terapia , Pesquisa Qualitativa , Empatia , Satisfação PessoalRESUMO
Physalis alkekengi L. var. franchetii (Mast.) Makino (PA) is a natural plant which is utilised as a traditional herbal medicine. It has properties that make it effective against inflammation and free radical damage. In the present study, the major constituents of four extraction parts of the fruits of PA (PAF) were investigated by combining ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). The mice model of Alzheimer's disease (AD) induced by aluminum chloride (AlCl3 ) combined with D-galactose (D-gal) was established to comprehend the mechanism behind PAF's anti-AD activity from both behavioural and pathological perspectives. The results showed that four extraction parts of PAF (PAFE) had favorable anti-AD effects and the ethyl acetate (EA) group showed the best activity. UPLC-Q-TOF-MS analysis identified Physalin B, Nobiletin and Caffeic acid as the main anti-AD active constituents in EA extract. This study reveals that PAF can reduce neuroinflammatory damage by inhibiting p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway, which is the theoretical basis for clinical development and utilization of PAF in AD therapy.