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Group 3 innate lymphoid cell (ILC3)-mediated production of the cytokine interleukin-22 (IL-22) is critical for the maintenance of immune homeostasis in the gastrointestinal tract. Here, we find that the function of ILC3s is not constant across the day, but instead oscillates between active phases and resting phases. Coordinate responsiveness of ILC3s in the intestine depended on the food-induced expression of the neuropeptide vasoactive intestinal peptide (VIP). Intestinal ILC3s had high expression of the G protein-coupled receptor vasoactive intestinal peptide receptor 2 (VIPR2), and activation by VIP markedly enhanced the production of IL-22 and the barrier function of the epithelium. Conversely, deficiency in signaling through VIPR2 led to impaired production of IL-22 by ILC3s and increased susceptibility to inflammation-induced gut injury. Thus, intrinsic cellular rhythms acted in synergy with the cyclic patterns of food intake to drive the production of IL-22 and synchronize protection of the intestinal epithelium through a VIP-VIPR2 pathway in ILC3s.
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Imunidade nas Mucosas/imunologia , Subpopulações de Linfócitos/imunologia , Linfócitos/imunologia , Periodicidade , Peptídeo Intestinal Vasoativo/imunologia , Animais , Ingestão de Alimentos/imunologia , Imunidade Inata/imunologia , Subpopulações de Linfócitos/metabolismo , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Peptídeo Intestinal Vasoativo/metabolismoRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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The medial prefrontal cortex (mPFC) is a key brain structure for higher cognitive functions such as decision-making and goal-directed behavior, many of which require awareness of spatial variables including one's current position within the surrounding environment. Although previous studies have reported spatially tuned activities in mPFC during memory-related trajectory, the spatial tuning of mPFC network during freely foraging behavior remains elusive. Here, we reveal geometric border or border-proximal representations from the neural activity of mPFC ensembles during naturally exploring behavior, with both allocentric and egocentric boundary responses. Unlike most of classical border cells in the medial entorhinal cortex (MEC) discharging along a single wall, a large majority of border cells in mPFC fire particularly along four walls. mPFC border cells generate new firing fields to external insert, and remain stable under darkness, across distinct shapes, and in novel environments. In contrast to hippocampal theta entrainment during spatial working memory tasks, mPFC border cells rarely exhibited theta rhythmicity during spontaneous locomotion behavior. These findings reveal spatially modulated activity in mPFC, supporting local computation for cognitive functions involving spatial context and contributing to a broad spatial tuning property of cortical circuits.
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Córtex Pré-Frontal , Ritmo Teta , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/citologia , Animais , Ritmo Teta/fisiologia , Masculino , Camundongos , Córtex Entorrinal/fisiologia , Neurônios/fisiologia , Hipocampo/fisiologia , Memória Espacial/fisiologia , Camundongos Endogâmicos C57BL , Memória de Curto Prazo/fisiologiaRESUMO
Hepatoblastoma (HB), a primary liver tumour, is notorious for its high metastatic potential and poor prognosis. Ganoderma lucidum, an edible mushroom species utilized in traditional Chinese medicine for addressing various tumour types, presents an intriguing avenue for HB treatment. However, the effectiveness of G. lucidum in managing HB and its underlying molecular mechanism necessitates further exploration. Standard in vitro assays were conducted to evaluate the impact of sporoderm-broken spores of G. lucidum (SBSGL) on the malignant characteristics of HB cells. The mechanism of SBSGL in treating HB and its tumour immunomodulatory effects were explored and validated by various experiments, including immunoprecipitation, Western blotting, mRFP-GFP-LC3 adenovirus transfection and co-localization analysis, as well as verified with in vivo experiments in this regard. The results showed that SBSGL effectively inhibited the malignant traits of HB cells and suppressed the O-GlcNAcylation of RACK1, thereby reducing its expression. In addition, SBSGL inhibited immune checkpoints and regulated cytokines. In conclusion, SBSGL had immunomodulatory effects and regulated the malignancy and autophagy of HB by regulating the O-GlcNAcylation of RACK1. These findings suggest that SBSGL holds promise as a potential anticancer drug for HB treatment.
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Hepatoblastoma , Neoplasias Hepáticas , Reishi , Hepatoblastoma/tratamento farmacológico , Hepatoblastoma/genética , Esporos Fúngicos , Autofagia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genéticaRESUMO
OBJECTIVES: The characteristics of brain impairment in different subtypes of systemic sclerosis (SSc) (dcSSc, diffuse cutaneous SSc; lcSSc, limited cutaneous SSc) remain unclear. This study aimed to characterize cerebral structure and perfusion changes in different subtype of SSc patients using magnetic resonance (MR) imaging. METHODS: Seventy SSc patients (46.0 ± 11.7 years, 62 females) and 30 healthy volunteers (44.8 ± 13.7 years, 24 females) were recruited and underwent brain MR imaging and Montreal Cognitive Assessment (MoCA) test. Gray matter (GM) volumes were measured using voxel-based morphometry analysis on T1-weighted images. Voxel-based and regional cerebral blood flow (CBF) was calculated on arterial spin labelling images. The cerebral structural and perfusion measurements by MR imaging were compared among dcSSc, lcSSc and healthy subjects using one-way ANOVA. The correlations between clinical characteristics and MR imaging measurements were also analyzed. RESULTS: The dcSSc patients exhibited a significant reduction in GM volume in the para-hippocampal region (cluster p < 0.01, FWE corrected) compared with healthy volunteers. Whereas, SSc patients, particularly lcSSc patients, showed elevated CBF in cerebellum, insula, cerebral cortex, and subcortical structures (regional analyses: all p < 0.05; voxel-based analyses: cluster p < 0.01, FWE corrected). Furthermore, clinical characteristics of modified Rodnan skin score (mRSS) (r value ranged from -0.29 to -0.45), MoCA scores (r = 0.40) and antinuclear antibody (ANA) positivity (r=-0.33) were significantly associated with CBF in some regions (all p < 0.05). CONCLUSION: The manifestations of brain involvement vary among different subtypes of SSc. In addition, severe skin sclerosis may indicate higher risk of brain involvement in SSc patients.
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The development of anti-AD drugs has attracted much attention as the number of AD patients is increasing year by year. Five diosmetin derivatives (1-5) were designed and synthesized by introducing carbamate groups. The crystal structure of 1 was analyzed by X-ray diffraction, which showed a large conjugated coplanar structure and might be favorable for the insertion into the Aß folding. Meanwhile, in vitro experiments were carried out to investigate the anticholinesterase activity, metal chelating property, antioxidant activity, and anti-Aß aggregation ability of 1-5. The results showed that 1-5 had good cholinesterase inhibitory activities. Compound 4 showed the highest inhibitory activities against butyrylcholinesterase (IC50 = 0.0760 µM). Further kinetic experiments and molecular docking studies showed that 4 could bind well to butyrylcholinesterase. The molecular dynamics simulations also signified that compared with diosmetin, 4 could reduce the flexibility of the butyrylcholinesterase protein skeleton to a greater extent, and thus had a better inhibitory effect. In addition, 1-5 could selectively chelate copper ions and all of them had good antioxidant activity as well as anti-Aß aggregation ability. Among them, 4 had the strongest activity to inhibit Cu2+-induced Aß aggregation (51.09%) and had low cytotoxicity. In addition, in vivo ROS activity assay (Caenorhabditis elegans) showed that 4 had the ability to scavenge ROS. Besides, the in vivo Aß aggregation assay showed that 4 could reduce Aß aggregation. In conclusion, 4 has the potential to be developed into a multifunctional anti-AD drug.
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BACKGROUND: Prostate cancer is a disease that seriously troubles men. However, there are some inevitable limitations in interventional therapy for prostate cancer patients at present, most of which are caused by low selectivity and high toxic side effects due to unclear drug targets. In this study, we identified the target protein of Curcusone C with anti-prostate cancer potential activity and verified its target and mechanism of action. METHODS: Click chemistry-activity based proteomics profiling (CC-ABPP) method was used to find target protein of Curcusone C against prostate cancer. Competitive CC-ABPP, drug affinity responsive target stability (DARTS) and surface plasmon resonance (SPR) methods were used to verifying the target protein. Moreover, potential mechanism was validated by western blot in vitro and by hematoxylin-eosin (HE) staining, detection of apoptosis in tumor tissue (TUNEL), and immunohistochemical (IHC) in vivo. RESULTS: We found that poly(rC)-binding protein 2 (PCBP2) was the target protein of Curcusone C. In addition, Curcusone C might disrupt the Bax/Bcl-2 balance in PC-3 cells by inhibiting the expression of the target protein PCBP2, thereby inducing mitochondrial damage and activation of the mitochondrial apoptosis pathway, and ultimately inducing apoptosis of prostate cancer cells. CONCLUSIONS: Curcusone C is a potential compound with anti-prostate cancer activity, and this effect occurs by targeting the PCBP2 protein, which in turn may affect the TGF/Smad signaling pathway and Bax/Bcl-2 balance. Our results laid a material and theoretical foundation for Curcusone C, to be widely used in anti-prostate cancer.
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Proteínas de Transporte , Neoplasias da Próstata , Masculino , Humanos , Proteína X Associada a bcl-2/metabolismo , Proteômica , Química Click , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias da Próstata/patologia , Apoptose , Linhagem Celular Tumoral , Proteínas de Ligação a RNA/metabolismoRESUMO
BACKGROUND: T1 , T2 , and T2 * mappings are seldom performed in a single examination, and their values in evaluating symptomatic atherosclerosis are lacking. PURPOSE: To perform three-dimensional (3D) quantitative T1 , T2 , and T2 * mappings (SQUMA) multi-parametric imaging for carotid vessel wall and evaluate its reliability and value in assessing carotid atherosclerosis. STUDY TYPE: Prospective. SUBJECTS: Eight healthy subjects and 20 patients with symptomatic carotid atherosclerosis. FIELD STRENGTH/SEQUENCE: 3 T, SQUMA imaging T1 -, T2 -, and T2 *-mapping, multi-contrast vessel wall imaging including T1 - and T2 -weighted, time-of-flight, and SNAP sequences. ASSESSMENT: SQUMA was acquired in all subjects and multi-contrast images were acquired in healthy subjects. T1 , T2 , and T2 * values and lumen area (LA), wall area (WA), mean wall thickness (MeanWT), and normalized wall index (NWI) of carotid arteries were measured. SQUMA and multi-contrast measurements were compared in healthy subjects and differences in SQUMA measurements between healthy subjects and patients were assessed. The discriminative value of SQUMA measurements for symptomatic vessel was determined. STATISTICAL TESTS: Paired t or Wilcoxon signed-rank test, independent t or Mann-Whitney U test, area under the receiver operating characteristic curve (AUC), intraclass correlation coefficients, and Bland-Altman plots. Statistically significant level, P < 0.05. RESULTS: There were no significant differences in LA (P = 0.340), WA (P = 0.317), MeanWT (P = 0.088), and NWI (P = 0.091) of carotid arteries between SQUMA and multi-contrast vessel wall images. The values of T2 (50.9 ± 2.9 msec vs. 44.5 ± 4.2 msec), T2 * (28.2 ± 4.3 msec vs. 24.7 ± 2.6 msec), WA (23.7 ± 4.6 mm2 vs. 36.2 ± 7.7 mm2 ), MeanWT (0.99 ± 0.05 mm vs. 1.50 ± 0.28 mm), and NWI (40.7 ± 3.0% vs. 53.8 ± 5.4%) of carotid arteries in healthy subjects were significantly different from those in atherosclerotic patients. The combination of quantitative T1 , T2 , and T2 * values and MeanWT showed greatest AUC (0.81; 95% CI: 0.65-0.92) in discriminating symptomatic vessels. DATA CONCLUSION: Carotid MR 3D quantitative multi-parametric imaging of SQUMA enables acquisition of T1 , T2 , and T2 * maps, reliably measuring carotid morphology and discriminating carotid symptomatic atherosclerosis. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.
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Aterosclerose , Doenças das Artérias Carótidas , Humanos , Reprodutibilidade dos Testes , Estudos Prospectivos , Imageamento por Ressonância Magnética/métodos , Imageamento Tridimensional/métodos , Artérias CarótidasRESUMO
Organohalide-respiring bacteria (OHRB)-mediated reductive dehalogenation is promising in in situ bioremediation of chloroethene-contaminated sites. The bioremediation efficiency of this approach is largely determined by the successful colonization of fastidious OHRB, which is highly dependent on the presence of proper growth niches and microbial interactions. In this study, based on two ecological principles (i.e., Priority Effects and Coexistence Theory), three strategies were developed to enhance niche colonization of OHRB, which were tested both in laboratory experiments and field applications: (i) preinoculation of a niche-preparing culture (NPC, being mainly constituted of fermenting bacteria and methanogens); (ii) staggered fermentation; and (iii) increased inoculation of CE40 (a Dehalococcoides-containing tetrachloroethene-to-ethene dechlorinating enrichment culture). Batch experimental results show significantly higher dechlorination efficiencies, as well as lower concentrations of volatile fatty acids (VFAs) and methane, in experimental sets with staggered fermentation and niche-preconditioning with NPC for 4 days (CE40_NPC-4) relative to control sets. Accordingly, a comparatively higher abundance of Dehalococcoides as major OHRB, together with a lower abundance of fermenting bacteria and methanogens, was observed in CE40_NPC-4 with staggered fermentation, which indicated the balanced syntrophic and competitive interactions between OHRB and other populations for the efficient dechlorination. Further experiments with microbial source tracking analyses suggested enhanced colonization of OHRB by increasing the inoculation ratio of CE40. The optimized conditions for enhanced colonization of OHRB were successfully employed for field bioremediation of trichloroethene (TCE, 0.3-1.4 mM)- and vinyl chloride (VC, â¼0.04 mM)-contaminated sites, resulting in 96.6% TCE and 99.7% VC dechlorination to ethene within 5 and 3 months, respectively. This study provides ecological principles-guided strategies for efficient bioremediation of chloroethene-contaminated sites, which may be also employed for removal of other emerging organohalide pollutants.
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Chloroflexi , Cloreto de Vinil , Bactérias , Biodegradação Ambiental , Interações MicrobianasRESUMO
Chloroethenes (CEs) as common organic pollutants in soil could be attenuated via abiotic and biotic dechlorination. Nonetheless, information on the key catalyzing matter and their reciprocal interactions remains scarce. In this study, FeS was identified as a major catalyzing matter in soil for the abiotic dechlorination of CEs, and acetylene could be employed as an indicator of the FeS-mediated abiotic CE-dechlorination. Organohalide-respiring bacteria (OHRB)-mediated dechlorination enhanced abiotic CEs-to-acetylene potential by providing dichloroethenes (DCEs) and trichloroethene (TCE) since chlorination extent determined CEs-to-acetylene potential with an order of trans-DCE > cis-DCE > TCE > tetrachloroethene/PCE. In contrast, FeS was shown to inhibit OHRB-mediated dechlorination, inhibition of which could be alleviated by the addition of soil humic substances. Moreover, sulfate-reducing bacteria and fermenting microorganisms affected FeS-mediated abiotic dechlorination by re-generation of FeS and providing short chain fatty acids, respectively. A new scenario was proposed to elucidate major abiotic and biotic processes and their reciprocal interactions in determining the fate of CEs in soil. Our results may guide the sustainable management of CE-contaminated sites by providing insights into interactions of the abiotic and biotic dechlorination in soil.
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Poluentes Ambientais , Tricloroetileno , Cloreto de Vinil , Solo , Substâncias Húmicas , Acetileno , HalogenaçãoRESUMO
Alzheimer's disease (AD) is a progressive neurodegenerative disease with complex pathogenesis. Despite the pathogenesis is unknown, the misfolding and accumulation of ß-amyloid (Aß) peptide play the important role in the occurrence and development of AD. Hence, multi-aspect intervention of the misfolded Aß peptides aggregation is a promising therapy for AD. In previous work, we obtained the emodin derivatives (a-d) with multifunctional anti-AD activities, including metal ions chelation, cholinesterase inhibition, and hydroxyl/superoxide anion radical elimination. In this work, we predicted the interaction of emodin derivatives (a-d) with Aß by combining molecular docking simulation and molecular dynamics simulation, and evaluated the ability to intervene with the self-, Cu2+- and AChE-induced Aß aggregation via in vitro methods. The results indicated that a-d could act as the potent multi-aspect intervention agents for Aß aggregation. In addition, a-d could effectively eliminate peroxyl radical, had virtually no neurotoxicity, and protect cells from oxidative and Aß-induced damage. The prediction results of ADMET properties showed that a-d had suitable pharmacokinetic characteristics. It suggested that a-d could act as the promising multi-targeted directed ligands (MTDLs) for AD. These results may provide meaningful information for the development of the potential MTDLs for AD which are modified from natural-origin scaffolds.
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Background: Hepatocellular carcinoma is a rapidly advancing malignancy with a poor prognosis. Therefore, further research is needed on its potential pathogenesis and therapeutic targets. Methods: In this study, the relevant datasets were downloaded from the TCGA database and the key modules were identified using WGCNA in the necroptosis-related gene set, while single-cell datasets were scored using the necroptosis gene set. Differential genes in the high- and low-expression groups were determined using the WGCNA module genes as intersection sets to identify key genes involved in necroptosis in liver cancer. Then, prognostic models were constructed using LASSO COX regression followed by multi-faceted validation. Finally, model genes were found to be correlated with key proteins of the necroptosis pathway and used to identify the most relevant genes, followed by their experimental validation. Subsequently, on the basis of the analysis results, the most relevant SFPQ was selected for cell-level verification. Results: We constructed a prognosis model that included five necroptosis-related genes (EHD1, RAC1, SFPQ, DAB2 and PABPC4) to predict the prognosis and survival of HCC patients. The results showed that the prognosis was more unfavorable in the high-risk group compared to the low-risk group, which was corroborated using ROC curves and risk factor plots. In addition, we further checked the differential genes using GO and KEGG analyses and found that they were predominantly enriched in the neuroactive ligand-receptor interaction pathway. The results of the GSVA analysis demonstrated that the high-risk group was mainly enriched in DNA replication, regulation of the mitotic cycle, and regulation of various cancer pathways, while the low-risk group was predominantly enriched in the metabolism of drugs and xenobiotics using cytochrome P450. SFPQ was found to be the main gene that affects the prognosis and SFPQ expression was positively correlated with the expression of RIPK1, RIPK3 and MLKL. Furthermore, the suppression of SFPQ could inhibit hyper-malignant phenotype HCC cells, while the WB results showed that inhibition of SFPQ expression also resulted in lower expression of necroptosis proteins, compared to the sh-NC group. Conclusions: Our prognostic model could accurately predict the prognosis of patients with HCC to further identify novel molecular candidates and interventions that can be used as alternative methods of treatment for HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Prognóstico , Bases de Dados Factuais , Necroptose , Proteínas de Transporte VesicularRESUMO
Coumarins and their derivatives possessed a variety of biological activities and some of coumarin-based drugs have been approved by the US Food and Drug Administration. Alzheimer's disease (AD) has caused great losses to human society. However, due to its complex pathogenesis, the ideal therapeutic approach has not been found yet. Free radical scavenging activity which is one of the main activities of coumarin core structure is closely related to other anti-AD activities. Therefore, in this work coumarins were chosen as privileged lead compounds for the development of anti-AD drugs based on strategy of multi-target directed ligands (MTDLs). Derivatives 1-3 which could modulate multiple targets simultaneously, including ROS, cholinesterase, ßamyloid (Aß) aggregation, and metal dyshomeostasis were designed and for the first time synthesized. Their anti-AD activities were studied both inâ vitro and inâ silico. Results showed that 1-3 possessed potent antioxidant activities and 7-OH group did change the electron distribution of the molecule and enhance the antioxidant activities. They also have good inhibition activities on acetylcholinesterase (AChE) and Aß aggregation and compound 1 had the strongest AChE inhibitory effect among the three compounds (AChE IC50 =11.15â µM). Compound 1-3 could also selectively chelate with Cu2+ and Al3+ to regulate the metal homeostasis. Inâ silico simulations, including molecular docking and prediction of ADMET performance, indicated that 1-3 could interact with target proteins and cross the blood brain barrier. In conclusion, 1-3 could be promising MTDLs applied as anti-AD candidate drugs.
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Doença de Alzheimer , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Antioxidantes/química , Simulação de Acoplamento Molecular , Acetilcolinesterase/metabolismo , Peptídeos beta-Amiloides/metabolismo , Inibidores da Colinesterase/química , Cumarínicos/química , Desenho de Fármacos , Relação Estrutura-AtividadeRESUMO
The present study was aimed to investigate whether Gasdermin D (GSDMD)-mediated pyroptosis participated in lipopolysaccharide (LPS)-induced sepsis-associated acute kidney injury (AKI), and to explore the role of caspase-1 and caspase-11 pyroptosis pathways in this process. The mice were divided into four groups: wild type (WT), WT-LPS, GSDMD knockout (KO) and KO-LPS. The sepsis-associated AKI was induced by intraperitoneal injection of LPS (40 mg/kg). Blood samples were taken to determine the concentration of creatinine and urea nitrogen. The pathological changes of renal tissue were observed via HE staining. Western blot was used to investigate the expression of pyroptosis-associated proteins. The results showed that the concentrations of serum creatinine and urea nitrogen in the WT-LPS group were significantly increased, compared with those in the WT group (P < 0.01); whereas serum creatinine and urea nitrogen in the KO-LPS group were significantly decreased, compared with those in the WT-LPS group (P < 0.01). HE staining results showed that LPS-induced renal tubular dilatation was mitigated in GSDMD KO mice. Western blot results showed that LPS up-regulated the protein expression levels of interleukin-1ß (IL-1ß), GSDMD and GSDMD-N in WT mice. GSDMD KO significantly down-regulated the protein levels of IL-1ß, caspase-11, pro-caspase-1, caspase-1(p22) induced by LPS. These results suggest that GSDMD-mediated pyroptosis is involved in LPS-induced sepsis-associated AKI. Caspase-1 and caspase-11 may be involved in GSDMD cleavage.
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Injúria Renal Aguda , Caspases , Sepse , Animais , Camundongos , Caspase 1 , Caspases/metabolismo , Creatinina , Lipopolissacarídeos , Camundongos Knockout , Nitrogênio , Ureia , Gasderminas/metabolismoRESUMO
PURPOSE: To propose a free-breathing simultaneous multi-delay arterial spin labeling (ASL) and T1 mapping technique with a stepwise kinetic model for renal assessment in a single 4-min scan at 3 T. METHODS: The proposed saturated multi-delay renal arterial spin labeling (SAMURAI) sequence used flow-sensitive alternating inversion recovery (FAIR) preparation, followed by acquisition of 9 images with Look-Locker spoiled gradient recalled echo (SPGR). Pre-saturation at the imaging slice was used to achieve saturation-based T1 mapping. A 4-step 2-compartment kinetic model was proposed to characterize water transition through artery- and tissue-compartment. The impact of the Look-Locker sampling scheme on the ASL signal was corrected in this model. T1 estimation with dictionary searching method and perfusion quantification based on the proposed kinetic model fitting were conducted after groupwise registration of the acquired images. The feasibility and repeatability of SAMURAI were validated in healthy subjects (n = 11) and patients with different renal diseases (n = 4). RESULTS: The proposed SAMURAI technique can provide accurate T1 map with strong correlation (R2 = 0.98) with inversion recovery spin echo (IR-SE) on phantom. SAMURAI provided equally reliable whole kidney and cortical ASL and T1 quantification results compared with multi-TI FAIR (intraclass correlation coefficient [ICC], 0.880-0.958) and IR-SPGR (ICC, 0.875-0.912), respectively. Low renal blood flow and increased T1 were detected by SAMURAI in the affected kidneys of the patients. SAMURAI had excellent scan-rescan repeatability (ICC, 0.905-0.992) and significantly reduced scan time (4 min 6 s vs. 45 min for 9 TIs) compared to multi-TI FAIR. CONCLUSION: The proposed SAMURAI technique is feasible and repeatable for simultaneously quantifying T1 and perfusion of kidneys with high time-efficiency.
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Rim , Circulação Renal , Voluntários Saudáveis , Humanos , Rim/irrigação sanguínea , Rim/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Perfusão , Reprodutibilidade dos Testes , Marcadores de SpinRESUMO
Bistable mechanical vibration is observed in a cavity magnomechanical system, which consists of a microwave cavity mode, a magnon mode, and a mechanical vibration mode of a ferrimagnetic yttrium-iron-garnet sphere. The bistability manifests itself in both the mechanical frequency and linewidth under a strong microwave drive field, which simultaneously activates three different kinds of nonlinearities, namely, magnetostriction, magnon self-Kerr, and magnon-phonon cross-Kerr nonlinearities. The magnon-phonon cross-Kerr nonlinearity is first predicted and measured in magnomechanics. The system enters a regime where Kerr-type nonlinearities strongly modify the conventional cavity magnomechanics that possesses only a radiation-pressure-like magnomechanical coupling. Three different kinds of nonlinearities are identified and distinguished in the experiment. Our Letter demonstrates a new mechanism for achieving mechanical bistability by combining magnetostriction and Kerr-type nonlinearities, and indicates that such Kerr-modified cavity magnomechanics provides a unique platform for studying many distinct nonlinearities in a single experiment.
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AIMS: The association between haemoglobin A1c (HbA1c) and cerebral microbleeds (CMBs) remains unclear. We aimed to investigate the association between HbA1c and CMBs in community-based individuals without stroke or transient ischaemic attack (TIA) and whether the association differs between individuals with and without diabetes mellitus (DM). MATERIALS AND METHODS: All individuals were recruited from a community in Beijing, China, from January 2015 to September 2019. All individuals completed a questionnaire and underwent blood tests and brain magnetic resonance imaging. A susceptibility-weighted imaging sequence was acquired to detect CMBs, which were defined as small, round and low-signal lesions with <10 mm diameter. The association between HbA1c and CMBs was analysed using multivariable logistic regression adjusted for demographics, medical history and blood sample test results. Subgroup analyses stratified by history of DM were performed. RESULTS: Of 544 recruited individuals, 119 (21.88%) had CMBs. HbA1c was independently associated with CMBs (odds ratio [OR], 1.51; 95% confidence interval [CI], 1.03-2.22). In 87 individuals with DM, multivariable logistic analysis showed that HbA1c was significantly associated with CMBs (OR, 1.67; 95% CI, 1.04-2.69), whereas in individuals without DM, no significant association was observed between HbA1c and CMBs (OR, 1.07; 95% CI, 0.50-2.30). CONCLUSIONS: HbA1c was associated with CMBs in individuals without stroke or TIA, particularly in individuals with DM, suggesting that the status of glycaemic control warrants attention for the prevention of CMBs. It would be beneficial to manage HbA1c specifically to control the risk of CMBs, especially in individuals with DM.
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Hemorragia Cerebral , Hemoglobinas Glicadas , Ataque Isquêmico Transitório , Acidente Vascular Cerebral , Hemorragia Cerebral/sangue , Hemorragia Cerebral/epidemiologia , China/epidemiologia , Estudos Transversais , Hemoglobinas Glicadas/análise , Testes Hematológicos , Humanos , Ataque Isquêmico Transitório/sangue , Ataque Isquêmico Transitório/epidemiologia , Imageamento por Ressonância Magnética , Fatores de Risco , Acidente Vascular Cerebral/epidemiologiaRESUMO
Neddylation is a posttranslational modification that is similar to ubiquitination, and involved in some critical biological processes, such as DNA repair, transcription regulation, and ubiquitin-proteasome pathway. Recently, it was found that neddylation inhibitor MLN4924 has potent antiviral activity against human viruses including herpes simplex virus (HSV)-1, HSV-2, and influenza viruses. Here, we report that MLN4924 could dramatically and dose-dependently inhibits the propagation, formation of budding virus (BV) and occlusion body (OB) of a lepidopteran virus-Bombyx mori nucleopolyhedrovirus (BmNPV), impaired OB assembly. In addition, the neddylation modification protein NEDD8 is colocalized with aggresome and autophagosome. Our findings suggest that inhibiting neddylation could be an antibaculovirus strategy and MLN4924 may be used as candidate drug for that purpose.
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Bombyx , Nucleopoliedrovírus , Animais , Bombyx/genética , Humanos , Nucleopoliedrovírus/fisiologia , Processamento de Proteína Pós-Traducional , Replicação ViralRESUMO
A bis-dimethylamine substituted xanthone (Xan-2) was obtained by cationic modification of the free C3 and C6 hydroxy groups of 1,3,6-trihydroxyxanthone (Xan-1) which was isolated from Polygala hongkongensis Hemsl.. The results of the spectroscopic analysis, melting profiles, electrophoretic migration, PCR assay and molecular docking indicated that the hydrophobic plane of Xan-1 and Xan-2 could intercalate into the DNA base pairs meanwhile the basic amine alkyl chain of Xan-2 could bind with DNA phosphate framework via electrostatic interaction. Thus, Xan-2 exhibited higher DNA binding affinity than Xan-1. Further study showed that Xan-2 could inhibit the proliferation of HeLa, SGC-7901 and A549 cells effectively by MTT assay and induce apoptosis of HeLa cells as detected by AO/EB staining and flow cytometry assay. Interestingly, Xan-2 exhibited selective cytotoxicity to cells, which was proved by its relatively low inhibitory effect on Raw 264.7â cell. What these studies mean is that disubstituted amine alkyl chains will play an important role in DNA binding property and cytotoxic activity, providing a direction for the development of novel potential antitumor agents.
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Antineoplásicos , Antineoplásicos/química , Antineoplásicos/farmacologia , Proliferação de Células , DNA/química , Dimetilaminas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Simulação de Acoplamento MolecularRESUMO
The pressure change rate (PCR) of the brake chamber is the key control parameter and evaluation index in the pneumatic braking system for intelligent braking. The PCR threshold value of commercial vehicle brake chambers for braking comfort is analyzed. The PCR measurement method based on a laminar flow resistance tube is proposed, and the PCR test system is designed. The simulation model of a PCR test system for commercial vehicle brake chambers is presented. By analyzing the simulation and experimental results, it is validated that the PCR test system of commercial vehicle brake chambers has the function of measuring PCR in real time. Finally, according to the MSA (Measurement System Analysis) evaluation method, the performance of the PCR test system for commercial vehicle brake chambers is analyzed, and the correctness and applicability of the test system are verified.