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High-fat diet (HFD) consumption may contribute to the high prevalence of cognitive-emotional issues in modern society. Mice fed a HFD for a prolonged period develop more severe neurobehavioral disturbances when first exposed to a HFD in the juvenile period than in adulthood, suggesting an initial age-related difference in the detrimental effects of long-term HFD feeding. However, the mechanism underlying this difference remains unclear. Here, male C57BL/6J mice initially aged 4 (IA4W) or 8 (IA8W) weeks were fed a control diet (CD) or HFD for 6 months and then subjected to metabolic, neurobehavioral, and histomorphological examinations. Although the detrimental effects of long-term HFD feeding on metabolism and neurobehavior were observed in mice of both ages, IA4W-HFD mice showed significant cognitive inflexibility accompanied by significantly greater levels of anxiety-like behavior than age-matched controls. Hippocampal neuroplasticity and microglial phenotype were altered by HFD feeding, whereas significant morphological alterations were more frequently observed in IA4W-HFD mice than in IA8W-HFD mice. Additionally, significantly increased hippocampal microglial engulfment of postsynaptic proteins and elevated phospho-insulin-receptor levels were observed in IA4W-HFD, but not in IA8W-HFD, mice. These findings suggest that aberrant microglia-related histomorphological changes in the hippocampus underlie the exacerbated detrimental neurobehavioral effects of prolonged early HFD exposure and indicate that enhanced insulin signaling might drive microglial dysfunction after prolonged early HFD exposure.
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Dieta Hiperlipídica , Insulina , Camundongos , Masculino , Animais , Dieta Hiperlipídica/efeitos adversos , Microglia , Camundongos Endogâmicos C57BL , Plasticidade Neuronal , Hipocampo/metabolismoRESUMO
The SARS-CoV-2 main protease (Mpro) plays a crucial role in virus amplification and is an ideal target for antiviral drugs. Currently, authentic Mpro is prepared through two rounds of proteolytic cleavage. In this method, Mpro carries a self-cleavage site at the N-terminus and a protease cleavage site followed by an affinity tag at the C-terminus. This article proposes a novel method for producing authentic Mpro through single digestion. Mpro was constructed by fusing a His tag containing TEV protease cleavage sites at the N-terminus. The expressed recombinant protein was digested by TEV protease, and the generated protein had a decreased molecular weight and significantly increased activity, which was consistent with that of authentic Mpro generated by the previous method. These findings indicated that authentic Mpro was successfully obtained. Moreover, the substrate specificity of Mpro was investigated. Mpro had a strong preference for Phe at position the P2, which suggested that the S2 subsite was an outstanding target for designing inhibitors. This article also provides a reference for the preparation of Mpro for sudden coronavirus infection in the future.
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Proteases 3C de Coronavírus , SARS-CoV-2 , SARS-CoV-2/enzimologia , SARS-CoV-2/genética , Proteases 3C de Coronavírus/genética , Proteases 3C de Coronavírus/química , Proteases 3C de Coronavírus/metabolismo , Especificidade por Substrato , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , COVID-19/virologiaRESUMO
The thymus, a site to culture the naïve T lymphocytes, is susceptible to atrophy or involution due to aging, inflammation, and oxidation. Epigallocatechin-3-gallate (EGCG) has been proven to possess anti-inflammatory, antioxidant, and antitumor activity. Here, we investigate the effects of EGCG on thymic involution induced by lipopolysaccharide (LPS), an endotoxin derived from Gram-negative bacteria. The methodology included an in vivo experiment on female Kunming mice exposed to LPS and EGCG. Morphological assessment of thymic involution, immunohistochemical detection, and thymocyte subsets analysis by flow cytometry were further carried out to evaluate the potential role of EGCG on the thymus. As a result, we found that EGCG alleviated LPS-induced thymic atrophy, increased mitochondrial membrane potential and superoxide dismutase levels, and decreased malondialdehyde and reactive oxygen species levels. In addition, EGCG pre-supplement restored the ratio of thymocyte subsets, the expression of autoimmune regulator, sex-determining region Y-box 2, and Nanog homebox, and reduced the number of senescent cells and collagen fiber deposition. Western blotting results indicated that EGCG treatment elevated LPS-induced decrease in pAMPK, Sirt1 protein expression. Collectively, EGCG relieved thymus architecture and function damaged by LPS via regulation of AMPK/Sirt1 signaling pathway. Our findings may provide a new strategy on protection of thymus from involution caused by LPS by using EGCG. And EGCG might be considered as a potential agent for the prevention and treatment of thymic involution.
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Proteínas Quinases Ativadas por AMP , Catequina , Lipopolissacarídeos , Transdução de Sinais , Sirtuína 1 , Timo , Animais , Catequina/análogos & derivados , Catequina/farmacologia , Sirtuína 1/metabolismo , Camundongos , Feminino , Timo/efeitos dos fármacos , Timo/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , AtrofiaRESUMO
BACKGROUND: A series of previous investigations have revealed that p-Smad3 plays a facilitative role in the differentiation and maturation of osteoblasts, while also regulating the expression of certain intercellular communication factors. However, the effects of p-Smad3 in osteoblasts before and after maturation on the proliferation, migration, differentiation, apoptosis and other cellular behaviors of osteoclasts have not been reported. METHODS: MC3T3-E1 cells were cultured in osteogenic induction medium for varying durations, After that, the corresponding conditioned medium was collected and the osteoclast lineage cells were treated. To elucidate the regulatory role of p-Smad3 within osteoblasts, we applied the activator TGF-ß1 and inhibitor SIS3 to immature and mature osteoblasts and collected corresponding conditioned media for osteoclast intervention. RESULTS: We observed an elevation of p-Smad3 and Smad3 during the early stage of osteoblast differentiation, followed by a decline in the later stage. we discovered that as osteoblasts mature, their conditioned media inhibit osteoclasts differentiation and the osteoclast-coupled osteogenic effect. However, it promotes apoptosis in osteoclasts and the angiogenesis coupled with osteoclasts. p-Smad3 in immature osteoblasts, through paracrine effects, promotes the migration, differentiation, and osteoclast-coupled osteogenic effects of osteoclast lineage cells. For mature osteoblasts, p-Smad3 facilitates osteoclast apoptosis and the angiogenesis coupled with osteoclasts. CONCLUSIONS: As pre-osteoblasts undergo maturation, p-Smad3 mediated a paracrine effect that transitions osteoclast cellular behaviors from inducing differentiation and stimulating bone formation to promoting apoptosis and coupling angiogenesis.
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Osteoclastos , Osteogênese , Proteína Smad3 , Diferenciação Celular , Meios de Cultivo Condicionados/farmacologia , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteogênese/genética , Osteogênese/fisiologia , Animais , Camundongos , Proteína Smad3/genética , Proteína Smad3/metabolismoRESUMO
Icaritin is a prenylflavonoid derivative of the genus Epimedium (Berberidaceae) and has a variety of pharmacological actions. Icaritin is approved by the National Medical Products Administration as an anticancer drug that exhibits efficacy and safety advantages in patients with hepatocellular carcinoma cells. This study aimed to evaluate the inhibitory effects of icaritin on UDP-glucuronosyltransferase (UGT) isoforms. 4-Methylumbelliferone (4-MU) was employed as a probe drug for all the tested UGT isoforms using in vitro human liver microsomes (HLM). The inhibition potentials of UGT1A1 and 1A9 in HLM were further tested by employing 17ß-estradiol (E2) and propofol (PRO) as probe substrates, respectively. The results showed that icaritin inhibits UGT1A1, 1A3, 1A4, 1A7, 1A8, 1A10, 2B7, and 2B15. Furthermore, icaritin exhibited a mixed inhibition of UGT1A1, 1A3, and 1A9, and the inhibition kinetic parameters (Ki) were calculated to be 3.538, 2.117, and 0.306 (µM), respectively. The inhibition of human liver microsomal UGT1A1 and 1A9 both followed mixed mechanism, with Ki values of 2.694 and 1.431 (µM). This study provides supporting information for understanding the drug-drug interaction (DDI) potential of the flavonoid icaritin and other UGT-metabolized drugs in clinical settings. In addition, the findings provide safety evidence for DDI when liver cancer patients receive a combination therapy including icaritin.
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Interações Medicamentosas , Flavonoides , Glucuronosiltransferase , Microssomos Hepáticos , Glucuronosiltransferase/antagonistas & inibidores , Glucuronosiltransferase/metabolismo , Humanos , Flavonoides/farmacologia , Microssomos Hepáticos/metabolismo , Estradiol/farmacologia , Himecromona/farmacologia , Propofol/farmacologia , Inibidores Enzimáticos/farmacologiaRESUMO
PURPOSE: To present a modified calibration method to reduce signal drift due to table sagging in Respiratory Gating for Scanner (RGSC) systems with a wall-mounted camera. MATERIALS AND METHODS: Approximately 70 kg of solid water phantoms were evenly distributed on the CT couch, mimicking the patient's weight. New calibration measurements were performed at 9 points at the combination of three lateral positions, the CT isocenter and ±10 cm laterally from the isocenter, and three longitudinal locations, the CT isocenter and ±30 cm or ±40 cm from the isocenter. The new calibration was tested in two hospitals. RESULTS: Implementing the new weighed calibration method at the extended distance yielded improved results during the DIBH scan, reducing the drift to within 1 from 3 mm. The extended calibration positions exhibited similarly reduced drift in both hospitals, reinforcing the method's robustness and its potential applicability across all centers. CONCLUSION: This proposed solution aims to minimize the systematic error in radiation delivery for patients undergoing motion management with wall-mounted camera RGSC systems, especially in conjunction with a bariatric CT couchtop.
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Aceleradores de Partículas , Humanos , Imagens de Fantasmas , Movimento (Física)RESUMO
PURPOSE: To assess the practicality of employing a commercial knowledge-based planning tool (RapidPlan) to generate adapted intact prostate and prostate bed volumetric modulated arc therapy (VMAT) plans on iterative cone-beam computed tomography (iCBCT) datasets. METHODS AND MATERIALS: Intact prostate and prostate bed RapidPlan models were trained utilizing planning data from 50 and 44 clinical cases, respectively. To ensure that refined models were capable of producing adequate clinical plans with a single optimization, models were tested with 50 clinical planning CT datasets by comparing dose-volume histogram (DVH) and plan quality metric (PQM) values between clinical and RapidPlan-generated plans. The RapidPlan tool was then used to retrospectively generate adapted VMAT plans on daily iCBCT images for 20 intact prostate and 15 prostate bed cases. As before, DVH and PQM metrics were utilized to dosimetrically compare scheduled (iCBCT Verify) and adapted (iCBCT RapidPlan) plans. Timing data was collected to further evaluate the feasibility of integrating this approach within an online adaptive radiotherapy workflow. RESULTS: Model testing results confirmed the models were capable of producing VMAT plans within a single optimization that were overall improved upon or dosimetrically comparable to original clinical plans. Direct application of RapidPlan on iCBCT datasets produced satisfactory intact prostate and prostate bed plans with generally improved target volume coverage/conformality and rectal sparing relative to iCBCT Verify plans as indicated by DVH values, though bladder metrics were marginally increased on average. Average PQM values for iCBCT RapidPlans were significantly improved compared to iCBCT Verify plans. The average time required [in mm:ss] to generate adapted plans was 06:09 ± 02:06 (intact) and 07:12 ± 01:04 (bed). CONCLUSION: This study demonstrated the feasibility of leveraging RapidPlan to expeditiously generate adapted VMAT intact prostate and prostate bed plans on iCBCT datasets. In general, adapted plans were dosimetrically improved relative to scheduled plans, emphasizing the practicality of the proposed approach.
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The quality of calibration datasets is critical for establishing well-calibrated models for reliable decision-making support. However, the analysis of the influence of calibration dataset quality and the discussion on how to use flawed and/or incomplete datasets are still far from sufficient. An evaluation framework for the impact of model calibration data on parameter identifiability, sensitivity, and uncertainty (ISU) was established. Three quantitative and normalized indicators were designed to describe the magnitude of ISU. With the case study of the upper Daqing River watershed, China and the model SWAT (Soil and Water Assessment Tool), one ideal dataset without quality flaws and 79 datasets with different types of flaws including observation error, low monitoring frequency, short data duration and low data resolution were evaluated. The result showed that 4 of 13 parameters that control canopy, groundwater and channel processes have higher ISU values, indicating the high identifiability, high sensitivity, and low uncertainty. The largest gap of parameter ISU between dataset with quality flaw and ideal dataset was 0.61 due to short data duration, while the smallest gap was -0.28 due to low monitoring data frequency. Although some defective datasets caused unacceptable calibration results and model output, some defective datasets can still be valuable for model calibration which depends on the hydrological processes of interest when applying the model. Equivalent calibration results were yielded by the datasets with similar statistical properties. When using datasets with traditional defective issues for calibration, a new step checking the consistency among decision goal, representative system process, determinative parameters and calibration datasets is suggested. Practices including process-related data selection, dataset regrouping and risk self-reporting when using low-quality datasets are encouraged to increase the reliability of model-based watershed management.
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Modelos Teóricos , Qualidade da Água , Calibragem , Reprodutibilidade dos Testes , SoloRESUMO
Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder in children and adolescents, and its etiology and pathogenesis are still unclear. Brain is the organ with the largest oxygen consumption in human body and is easily affected by oxidative imbalance. Oxidative stress has become the key research direction for the pathogenesis of ADHD, but there is still a lack of relevant studies in China. Based on the latest research findings in China and overseas, this article reviews the clinical and experimental studies on oxidative stress in ADHD and explores the association of oxidative stress with neurotransmitter imbalance, neuroinflammation, and cell apoptosis in the pathogenesis of ADHD, so as to provide new research ideas for exploring the pathogenesis of ADHD.
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Transtorno do Deficit de Atenção com Hiperatividade , Adolescente , Criança , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Estresse Oxidativo , Apoptose , Encéfalo , ChinaRESUMO
BACKGROUND: Concurrent chemoradiotherapy has been the standard of care for locally advanced cervical cancer for over 20 years; however, 30-40% of treated patients have recurrence or progression within 5 years. Immune checkpoint inhibition has improved outcomes for patients with PD-L1 positive metastatic or recurrent cervical cancer. We assessed the benefit of adding durvalumab, a PD-L1 antibody, with and following chemoradiotherapy for locally advanced cervical cancer. METHODS: The CALLA randomised, double-blind, phase 3 trial included 105 hospitals across 15 countries. Patients aged at least 18 years with previously untreated locally advanced cervical cancer (adenocarcinoma, squamous, or adenosquamous; International Federation of Gynaecology and Obstetrics [FIGO] 2009 stage IB2-IIB lymph node positive, stage ≥III any lymph node status) and WHO or Eastern Cooperative Oncology Group performance status of 0 or 1 were randomly assigned (1:1) through an interactive web response system using a permuted block size of 4 to receive durvalumab (1500 mg intravenously once every 4 weeks) or placebo with and following chemoradiotherapy, for up to 24 cycles. Chemoradiotherapy included 45 Gy external beam radiotherapy at 5 fractions per week concurrent with intravenous cisplatin (40 mg/m2) or carboplatin (area under the concentration-time curve 2) once weekly for 5 weeks, followed by image-guided brachytherapy (high-dose rate, 27·5-30 Gy or low-dose/pulse-dose rate, 35-40 Gy). Randomisation was stratified by disease stage status (FIGO stage and node status) and geographical region. Chemoradiotherapy quality was continuously reviewed. The primary endpoint was progression-free survival, assessed by the investigator using Response Evaluation Criteria in Solid Tumors, version 1.1, in the intention-to-treat population. Safety was assessed in patients who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, NCT03830866. FINDINGS: Between Feb 15, 2019, and Dec 10, 2020, 770 women were randomly assigned (385 to durvalumab and 385 to placebo; median age 49 years [IQR 41-57]). Median follow-up was 18·5 months (IQR 13·2-21·5) in the durvalumab group and 18·4 months (13·2-23·7) in the placebo group. At data cutoff, median progression-free survival had not been reached (95% CI not reached-not reached) for either group (HR 0·84; 95% CI 0·65-1·08; p=0·17); 12-month progression-free survival was 76·0% (71·3-80·0) with durvalumab and 73·3% (68·4-77·5) with placebo. The most frequently reported grade 3-4 adverse events in both groups were anaemia (76 [20%] of 385 in the durvalumab group vs 56 [15%] of 384 in the placebo group) and decreased white blood cells (39 [10%] vs 49 [13%]). Serious adverse events occurred for 106 (28%) patients who received durvalumab and 89 (23%) patients who received placebo. There were five treatment-related deaths in the durvalumab group (one case each of urinary tract infection, blood loss anaemia, and pulmonary embolism related to chemoradiotherapy only; one case of endocrine disorder related to durvalumab only; and one case of sepsis related to both durvalumab and chemoradiotherapy). There was one treatment-related death in the placebo group (pneumonia related to chemoradiotherapy). INTERPRETATION: Durvalumab concurrent with chemoradiotherapy was well tolerated in participants with locally advanced cervical cancer, however it did not significantly improve progression-free survival in a biomarker unselected, all-comers population. Concurrent durvalumab plus chemoradiotherapy warrants further exploration in patients with high tumoral PD-L1 expression. Rigorous monitoring ensured high chemoradiotherapy compliance with advanced technology and allowed patients to receive optimal care. FUNDING: AstraZeneca.
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Anemia , Neoplasias do Colo do Útero , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1 , Quimiorradioterapia/efeitos adversos , Método Duplo-Cego , Recidiva Local de Neoplasia , Neoplasias do Colo do Útero/tratamento farmacológicoRESUMO
The NMDA subtype glutamate receptors (NMDARs) play important roles in both physiological and pathologic processes in the brain. Compared with their critical roles in synaptic modifications and excitotoxicity in excitatory neurons, much less is understood about the functional contributions of NMDARs to the inhibitory GABAergic neurons. By using selective NMDAR inhibitors and potentiators, we here show that NMDARs bidirectionally modulate the intrinsic excitability (defined as spontaneous/evoked spiking activity and EPSP-spike coupling) in inhibitory GABAergic neurons in adult male and female mice. This modulation depends on GluN2C/2D- but not GluN2A/2B-containing NMDARs. We further show that NMDAR modulator EU1794-4 mostly enhances extrasynaptic NMDAR activity, and by using it we demonstrate a significant contribution of extrasynaptic NMDARs to the modulation of intrinsic excitability in inhibitory neurons. Together, this bidirectional modulation of intrinsic excitability reveals a previously less appreciated importance of NMDARs in the second-to-second functioning of inhibitory GABAergic neurons.SIGNIFICANCE STATEMENT NMDA subtype of glutamate receptors (NMDARs) have important roles in brain functions, including both physiological and pathologic ones. The role of NMDARs in inhibitory neurons has been less elucidated compared with that in excitatory neurons. Our results demonstrate the importance of GluN2C/GluN2D-containing but not GluN2A/GluN2B-containing extrasynaptic NMDARs in modulating the intrinsic excitability of inhibitory neurons. These results further suggest distinct contributions of subsynaptic locations and subunit compositions of NMDARs to their functions in excitatory and inhibitory neurons. The above findings have implications for better understanding of brain diseases, such as schizophrenia.
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N-Metilaspartato , Receptores de N-Metil-D-Aspartato , Animais , Feminino , Neurônios GABAérgicos , Ácido Glutâmico , Masculino , Camundongos , Sinapses/fisiologiaRESUMO
OBJECTIVE: This study aimed to propose a revised ypN (r-ypN) classification based on lymph node ratio (LNR) and to examine its prognostic value in postneoadjuvant esophageal cancer. BACKGROUND: A new postneoadjuvant pathologic (ypTNM) staging classification has been introduced for esophageal cancer. However, the ypN classification currently defined by the number of positive lymph nodes is influenced by the extent of lymphadenectomy. METHODS: Data on 7195 esophageal cancer patients receiving neoadjuvant chemoradiation were extracted from the National Cancer Database (NCDB). Four r-ypN stages were defined by 3 LNR thresholds (0%, 10%, and 20% using X-tile software). A revised ypTNM (r-ypTNM) classification was developed by solely changing N categories. Kaplan-Meier method and Cox proportional hazards models were used for survival analyses. Akaike information criterion (AIC) and Harrell's concordance index ( C -index) were used to compare the predictive performance of the current and the revised classification. External validation was performed using an independent cohort from the NEOCRTEC5010 clinical trial. RESULTS: Both ypN ( P <0.001) and r-ypN ( P <0.001) were independent prognostic factors of overall survival (OS) for esophageal cancer patients. Kaplan-Meier curves demonstrated a better discrimination with r-ypN than ypN categories. Within each ypN category (except ypN3), OS was significantly different comparing r-ypN strata; however, there were no differences between ypN strata within each r-ypN category (except r-ypN3). r-ypN (AIC: 60752 vs 60782; C -index: 0.591 vs 0.587) and r-ypTNM (AIC: 60623 vs 60628; C -index: 0.613 vs 0.610) showed better predictive performance than the current staging system, with a lower AIC (better calibration) and higher C -index (improved discrimination). This advantage was also confirmed by external validation using the NEOCRTEC5010 cohort. CONCLUSIONS: LNR showed better performance than ypN in predicting OS of esophageal cancer patients after neoadjuvant chemoradiation and may be an improvement on the current staging system.
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Neoplasias Esofágicas , Linfonodos , Humanos , Linfonodos/patologia , Terapia Neoadjuvante/métodos , Razão entre Linfonodos , Excisão de Linfonodo/métodos , Prognóstico , Estadiamento de Neoplasias , Estudos RetrospectivosRESUMO
The well-defined 2D or 3D structure of covalent organic frameworks (COFs) makes it have great potential in photoelectric conversion and ions conduction fields. Herein, a new donor-accepter (D-A) COF material, named PyPz-COF, constructed from electron donor 4,4',4â³,4'â³-(pyrene-1,3,6,8-tetrayl)tetraaniline and electron accepter 4,4'-(pyrazine-2,5-diyl)dibenzaldehyde with an ordered and stable π-conjugated structure is reported. Interestingly, the introduction of pyrazine ring endows the PyPz-COF a distinct optical, electrochemical, charge-transfer properties, and also brings plentiful CN groups that enrich the proton by hydrogen bonds to enhance the photocatalysis performance. Thus, PyPz-COF exhibits a significantly improved photocatalytic hydrogen generation performance up to 7542 µmol g-1 h-1 with Pt as cocatalyst, also in clear contrast to that of PyTp-COF without pyrazine introduction (1714 µmol g-1 h-1 ). Moreover, the abundant nitrogen sites of the pyrazine ring and the well-defined 1D nanochannels enable the as-prepared COFs to immobilize H3 PO4 proton carriers in COFs through hydrogen bond confinement. The resulting material has an impressive proton conduction up to 8.10 × 10-2 S cm-1 at 353 K, 98% RH. This work will inspire the design and synthesis of COF-based materials with both efficient photocatalysis and proton conduction performance in the future.
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The main protease (Mpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) plays a vital role in viral replication. To study the function of Mpro and screen inhibitors targeting Mpro, it is necessary to prepare high-purity and high-activity Mpro. In this study, four types of SARS-CoV-2 Mpros containing different termini were prepared, and their activities were determined successfully. The results showed that the activity of wild-type (WT) Mpro was the highest, and the additional residues at the N-terminus but not at the C-terminus had a major effect on the enzyme activity. To explain this, the alignment of structures of different forms of Mpro was determined, and the additional residues at the N-terminus were found to interfere with the formation of the substrate binding pocket. This study confirms the importance of the natural N-terminus to the activity of Mpro and suggests that WT-GPH6 (Mpro with eight additional residues at the C-terminus) can be used as a substitute for authentic Mpro to screen inhibitors. In short, this study provides a reference for the expression and purification of new coronaviruses confronted in the future.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , COVID-19/genética , Cisteína Endopeptidases/química , Inibidores de Proteases/farmacologia , Antivirais/química , Simulação de Acoplamento MolecularRESUMO
BACKGROUND: Little is known about the association between the preoperative low-density lipoprotein cholesterol (LDL-C) level and prognosis in patients with renal cell carcinoma (RCC) after nephrectomy, and its prognostic value needs to be elucidated. METHODS: The clinical and follow-up data of 737 RCC patients who underwent nephrectomy were retrospectively analyzed. The optimal cut-off LDL-C level was determined using X-tile, and then patients were divided into low and high LDL-C groups. The association between LDL-C levels and survival of RCC patients was assessed using the Kaplan-Meier method and Cox regression analysis. RESULTS: The optimal cut-off LDL-C level was 1.93 mmol/L, and patients were divided into the low (≤ 1.93 mmol/L) and high LDL-C (> 1.93 mmol/L) groups. The Kaplan-Meier analysis showed that patients in the low LDL-C group had significantly shorter overall survival (OS), cancer-specific survival (CSS) and recurrence-free survival (RFS) than those in the high LDL-C group (P = 0.001, P = 0.001, and P = 0.003, respectively). The COX univariate analysis showed that the preoperative LDL-C level was closely associated with OS, CSS, and RFS in RCC patients (P = 0.002, P = 0.003, and P = 0.005, respectively). The multivariate analysis showed that the preoperative LDL-C level was an independent factor for predicting survival (OS, CSS and RFS) in RCC patients after nephrectomy. The low preoperative LDL-C levels predicted worse OS (hazard ratio [HR]: 2.337; 95% confidence interval [CI]: 1.192-4.581; P = 0.013), CSS (HR: 3.347; 95% CI: 1.515-7.392; P = 0.003), and RFS (HR: 2.207; 95% CI: 1.178-4.132; P = 0.013). CONCLUSIONS: The preoperative LDL-C level is an independent factor for the prognosis of RCC patients after nephrectomy, and low preoperative LDL-C levels predict worse survival (OS, CSS, and RFS).
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Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Prognóstico , Neoplasias Renais/patologia , LDL-Colesterol , Estudos Retrospectivos , NefrectomiaRESUMO
The inwardly rectifying potassium channel Kir2.1 is closely associated with many cardiovascular diseases. However, the effect and mechanism of Kir2.1 in diabetic cardiomyopathy remain unclear. In vivo, we use STZ to establish the model, and ventricular structural changes, myocardial inflammatory infiltration, and myocardial fibrosis severity are detected by echocardiography, histological staining, immunohistochemistry, and western blot analysis, respectively. In vitro, a myocardial fibrosis model is established with high glucose. The Kir2.1 current amplitude, intracellular calcium concentration, fibrosis-related proteins, and TGF-ß1/Smad pathway proteins are detected by whole-cell patch clamp, calcium probes, western blot analysis, and immunofluorescence, respectively. The in vivo results show that compared to diabetic cardiomyopathy, zacopride (a Kir2.1 selective agonist) significantly reduces the left ventricular systolic diameter and diastolic diameter, increases the left ventricular ejection fraction and left ventricular short-axis shortening, improves the degree of cell necrosis, and reduces the expression of myocardial interstitial fibrosis protein and collagen fibre deposition area. The in vitro results show that the current amplitude and protein expression of Kir2.1 are both decreased in the high glucose-induced myocardial fibrosis model. Additionally, zacopride significantly upregulates the expression of Kir2.1 and inhibits the expressions of the fibrosis-related proteins α-SMA, collagen I, and collagen III. Activation of Kir2.1 reduces the intracellular calcium concentration and inhibits the protein expressions of TGF-ß1 and p-Smad 2/3. Activation of Kir2.1 can improve myocardial fibrosis induced by diabetic cardiomyopathy, and the possible mechanism may be related to inhibiting Ca 2+ overload and the TGF-ß1/Smad signaling pathway.
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Cardiomiopatias Diabéticas , Humanos , Cardiomiopatias Diabéticas/metabolismo , Volume Sistólico , Fator de Crescimento Transformador beta1/metabolismo , Cálcio , Função Ventricular Esquerda , Colágeno/metabolismo , Colágeno/farmacologia , Fibrose , Transdução de Sinais , Glucose/farmacologiaRESUMO
Interstock is an important agronomic technique for regulating plant growth and fruit quality, and overcoming the incompatibility between rootstocks and scions; however, the underlying mechanisms remain largely unknown. In this study, the effects and regulatory mechanisms of tangor grafting, with and without interstocks, on the growth and development of scions were analyzed by combining morphology, physiology, anatomy and transcriptomics. Morphological and physiological analyses showed that interstocks ('Aiyuan 38' and 'Daya') significantly improved the growth of seedlings, effectively enhanced the foliar accumulation of chlorophyll and carotenoids, and increased the thickness of leaf tissues. Using 'Aiyuan 38' as the interstock, photosynthetic efficiency and starch content of citrus seedlings improved. Transcriptomics showed that genes related to photosynthesis and photosynthetic antenna proteins were upregulated in interstock-treated seedlings, with significant upregulation of photosystem PSI- and PSII-related genes. In addition, multiple key genes may be involved in plant hormone signaling, starch and sucrose metabolism, and transcriptional regulation. Taken together, these findings provide novel insights into the role of interstocks in regulating and contributing to the growth and development of grafted seedlings, and will further define and deploy candidate genes to explore the mechanisms of rootstock-interstock-scion interactions.
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Citrus , Transcriptoma , Plântula/metabolismo , Perfilação da Expressão Gênica , Fotossíntese/genética , Citrus/genética , Raízes de Plantas/genéticaRESUMO
The association between a high-fat diet (HFD) consumption and emotional/cognitive disorders is widely documented. One distinctive feature of the prefrontal cortex (PFC), a kernel emotion- and cognition-related brain region, is its protracted adolescent maturation, which makes it highly vulnerable to the detrimental effects of environmental factors during adolescence. Disruption of the PFC structure and function is linked to emotional/cognitive disorders, especially those that emerge in late adolescence. A HFD consumption is common among adolescents, yet its potential effects on PFC-related neurobehavior in late adolescence and any related underlying mechanisms are yet to be established. In the present study, adolescent (postnatal days 28-56) male C57BL/6J mice were fed a control diet (CD) or a HFD and underwent behavioral tests in addition to Golgi staining and immunofluorescence targeting of the medial PFC (mPFC). The HFD-fed adolescent mice exhibited anxiety- and depression-like behavior and abnormal mPFC pyramidal neuronal morphology accompanied by alterations in microglial morphology indicative of a heightened state of activation and increased microglial PSD95+ inclusions signifying excessive phagocytosis of the synaptic material in the mPFC. These findings offer novel insights into the neurobehavioral effects due to adolescent HFD consumption and suggest a contributing role in microglial dysfunction and prefrontal neuroplasticity deficits for HFD-associated mood disorders in adolescents.
Assuntos
Dieta Hiperlipídica , Microglia , Camundongos , Animais , Masculino , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL , Neurônios , Córtex Pré-Frontal/fisiologiaRESUMO
Myocardial hypertrophy may lead to heart failure and sudden death. As traditional Chinese medicine, Guanxinning tablets (GXN) have significant pharmacological effects in the prevention and treatment of cardiovascular diseases. However, the anti-cardiac hypertrophy efficacy of GXN and its mechanism of action are still unclear. Therefore, we established a heart failure rat model and isolated primary cardiomyocytes of neonatal rat to observe the protective effect of GXN on heart failure rat model and the intervention effect on myocardial cell hypertrophy, and to explore the possible mechanism of GXN preventing and treating myocardial hypertrophy. The results of in vivo experiments showed that GXN could significantly reduce the degree of cardiac hypertrophy, reduce the size of cardiomyocytes, inhibit the degree of myocardial remodeling and fibrosis, and improve cardiac function in rats with early heart failure. The results of in vitro experiments showed that GXN was safe for primary cardiomyocytes and could improve cardiomyocyte hypertrophy and reduce the apoptosis of cardiomyocytes in pathological state, which may be related to the inhibition of the over-activation of MEK-ERK1/2 signaling pathway. In conclusion, GXN may inhibit cardiac hypertrophy and improve early heart failure by inhibiting the over-activation of MEK-ERK1/2 signaling pathway.
Assuntos
Insuficiência Cardíaca , Sistema de Sinalização das MAP Quinases , Animais , Ratos , Transdução de Sinais , Insuficiência Cardíaca/tratamento farmacológico , Comprimidos , Cardiomegalia/tratamento farmacológico , Quinases de Proteína Quinase Ativadas por MitógenoRESUMO
Linear chromosomes of eukaryotes are protected by a DNA-protein-RNA structure called telomere. Remarkably and unlike those of most organisms studied, Drosophila telomeric DNA is not composed of a group of short repeats, but three classes of retrotransposons at the chromosome ends. Telomeric transposons in Drosophila on the other hand serves the function of elongating the host chromosomes yet prevent little harm to the host genome as their insertion sites are strictly limited to the telomere. How the Drosophila host achieves such precise regulation is still unclear. The currently known genome-wide repression of transposon expression includes piRNA pathway and the heterochromatin pathway involving H3K9me3. Recent studies have found that Drosophila telomere capping proteins are involved in the specific regulation of telomeric retrotransposons. In this review, we discuss the specific functions of telomere capping proteins in regulating telomeric transposons. By studying how the Drosophila host interacts and regulates telomeric transposons, we hope to shed lights on universal principles in guiding their co-evolution.