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Activation of the Wnt-ß-catenin signaling pathway by CHIR99021, a specific inhibitor of GSK3ß, induces Tcf7l1 protein degradation, which facilitates the maintenance of an undifferentiated state in mouse embryonic stem cells (mESCs); however, the precise mechanism is still unclear. Here, we showed that the overexpression of transducin-ß-like protein 1 (Tbl1, also known as Tbl1x) or its family member Tblr1 (also known as Tbl1xr1) can decrease Tcf7l1 protein levels, whereas knockdown of each gene increases Tcf7l1 levels without affecting Tcf7l1 transcription. Interestingly, only Tbl1, and not Tblr1, interacts with Tcf7l1. Mechanistically, Tbl1 translocates from the cytoplasm into the nucleus in association with ß-catenin (CTNNB1) after the addition of CHIR99021 and functions as an adaptor to promote ubiquitylation of the Tcf7l1 protein. Functional assays further revealed that enforced expression of Tbl1 is capable of delaying mESC differentiation. In contrast, knockdown of Tbl1 attenuates the effect of CHIR99021 on Tcf7l1 protein stability and mESC self-renewal. Our results provide insight into the regulatory network of the Wnt-ß-catenin signaling pathway involved in promoting the maintenance of naïve pluripotency.
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Células-Tronco Embrionárias Murinas , Proteína 1 Semelhante ao Fator 7 de Transcrição , Via de Sinalização Wnt , beta Catenina , Animais , Humanos , Camundongos , beta Catenina/metabolismo , Proteínas Contendo Repetições de beta-Transducina/metabolismo , Proteínas Contendo Repetições de beta-Transducina/genética , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/metabolismo , Proteólise/efeitos dos fármacos , Piridinas/farmacologia , Pirimidinas/farmacologia , Proteína 1 Semelhante ao Fator 7 de Transcrição/metabolismo , Proteína 1 Semelhante ao Fator 7 de Transcrição/genética , UbiquitinaçãoRESUMO
Inhibition of protein kinase C (PKC) efficiently promoted the self-renewal of embryonic stem cells (ESCs). However, information about the function of PKC inhibition remains lacking. Here, RNA-sequencing showed that the addition of Go6983 significantly inhibited the expression of de novo methyltransferases (Dnmt3a and Dnmt3b) and their regulator Dnmt3l, resulting in global hypomethylation of DNA in mouse ESCs. Mechanistically, PR domain-containing 14 (Prdm14), a site-specific transcriptional activator, partially contributed to Go6983-mediated repression of Dnmt3 genes. Administration of Go6983 increased Prdm14 expression mainly through the inhibition of PKCδ. High constitutive expression of Prdm14 phenocopied the ability of Go6983 to maintain` mouse ESC stemness in the absence of self-renewal-promoting cytokines. In contrast, the knockdown of Prdm14 eliminated the response to PKC inhibition and substantially impaired the Go6983-induced resistance of mouse ESCs to differentiation. Furthermore, liquid chromatography-mass spectrometry profiling and Western blotting revealed low levels of Suv39h1 and Suv39h2 in Go6983-treated mouse ESCs. Suv39h enzymes are histone methyltransferases that recognize dimethylated and trimethylated histone H3K9 specifically and usually function as transcriptional repressors. Consistently, the inhibition of Suv39h1 by RNA interference or the addition of the selective inhibitor chaetocin increased Prdm14 expression. Moreover, chromatin immunoprecipitation assay showed that Go6983 treatment led to decreased enrichment of dimethylation and trimethylation of H3K9 at the Prdm14 promoter but increased RNA polymerase ⠡ binding affinity. Together, our results provide novel insights into the pivotal association between PKC inhibition-mediated self-renewal and epigenetic changes, which will help us better understand the regulatory network of stem cell pluripotency.
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Proteínas de Ligação a DNA , Células-Tronco Embrionárias Murinas , Proteína Quinase C , Animais , Camundongos , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Indóis/farmacologia , Maleimidas/farmacologia , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/enzimologia , Células-Tronco Embrionárias Murinas/fisiologia , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Inibidores de Proteínas Quinases/farmacologiaRESUMO
Iron (Fe) distribution and reutilization are crucial for maintaining Fe homeostasis in plants. Here, we demonstrate that the tomato (Solanum lycopersicum) Colorless nonripening (Cnr) epimutant exhibits increased Fe retention in cell wall pectin due to an increase in pectin methylesterase (PME) activity. This ultimately leads to Fe deficiency responses even under Fe-sufficient conditions when compared to the wild type (WT). Whole-genome bisulfite sequencing revealed that modifications to cell wall-related genes, especially CG hypermethylation in the intron region of PECTIN METHYLESTERASE53 (SlPME53), are involved in the Cnr response to Fe deficiency. When this intron hypermethylation of SlPME53 was artificially induced in WT, we found that elevated SlPME53 expression was accompanied by increased PME activity and increased pectin-Fe retention. The manipulation of SlPME53, either through overexpression in WT or knockdown in Cnr, influenced levels of pectin methylesterification and accumulation of apoplast Fe in roots. Moreover, CG hypermethylation mediated by METHYLTRANSFERASE1 (SlMET1) increased SlPME53 transcript abundance, resulting in greater PME activity and higher Fe retention in cell wall pectin. Therefore, we conclude that the Cnr mutation epigenetically modulates SlPME53 expression by SlMET1-mediated CG hypermethylation, and thus the capacity of the apoplastic Fe pool, creating opportunities for genetic improvement of crop mineral nutrition.
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Hidrolases de Éster Carboxílico , Epigênese Genética , Regulação da Expressão Gênica de Plantas , Ferro , Raízes de Plantas , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Hidrolases de Éster Carboxílico/genética , Ferro/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Metilação de DNA/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Parede Celular/metabolismo , Pectinas/metabolismoRESUMO
With no lysine/K kinases (WNKs) promote vasocontraction and vascular smooth muscle cell proliferation. In the prostate, smooth muscle contraction and growth may be critical for the development and medical treatment of voiding symptoms in benign prostatic hyperplasia. Here, we examined the effects of isoform-specific WNK silencing and of the WNK inhibitor WNK463 on growth-related functions and contraction in prostate stromal cells, and in human prostate tissues. Impacts of WNK silencing by transfection of cultured stromal cells with isoform-specific siRNAs were qualitatively and quantitatively similar for each WNK isoform. Effects of silencing were largest on cell death (3-5 fold increase in annexin V-positive/7-AAD-positive cells), on proliferation rate, Ki-67 mRNA expression and actin organization (reduced around two-thirds). Contraction in matrix contraction assays and viability were reduced to a lower degree (approximately half), but again to a similar extent for each WNK isoform. Effects of silencing were quantitatively and qualitatively reproduced by 10 µM WNK463, while 1 µM still induced cell death and breakdown in actin organization, without affecting proliferation or viability. Using 500 nM and 10 µM, WNK463 partly inhibited neurogenic and U46619-induced contractions of human prostate tissues (around half), while inhibition of α1-adrenergic contractions (around half) was limited to 10 µM. All four WNK isoforms suppress cell death and promote proliferation in prostate stromal cells. WNK-driven contraction of stromal cells appears possible, even though to a limited extent. Outcomes of isoform-specific WNK silencing can be fully reproduced by WNK463, including inhibition of smooth muscle contraction in human prostate tissues, but require high concentrations.
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Actinas , Próstata , Masculino , Humanos , Actinas/metabolismo , Contração Muscular/fisiologia , Células Estromais/metabolismo , Proliferação de Células , Isoformas de Proteínas/metabolismoRESUMO
BACKGROUND: CALCRL (calcitonin receptor-like) protein is an important mediator of the endothelial fluid shear stress response, which is associated with the genetic risk of coronary artery disease. In this study, we functionally characterized the noncoding regulatory elements carrying coronary artery disease that risks single-nucleotide polymorphisms and studied their role in the regulation of CALCRL expression in endothelial cells. METHODS: To functionally characterize the coronary artery disease single-nucleotide polymorphisms harbored around the gene CALCRL, we applied an integrative approach encompassing statistical, transcriptional (RNA-seq), and epigenetic (ATAC-seq [transposase-accessible chromatin with sequencing], chromatin immunoprecipitation assay-quantitative polymerase chain reaction, and electromobility shift assay) analyses, alongside luciferase reporter assays, and targeted gene and enhancer perturbations (siRNA and clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeat-associated 9) in human aortic endothelial cells. RESULTS: We demonstrate that the regulatory element harboring rs880890 exhibits high enhancer activity and shows significant allelic bias. The A allele was favored over the G allele, particularly under shear stress conditions, mediated through alterations in the HSF1 (heat shock factor 1) motif and binding. CRISPR deletion of rs880890 enhancer resulted in downregulation of CALCRL expression, whereas HSF1 knockdown resulted in a significant decrease in rs880890-enhancer activity and CALCRL expression. A significant decrease in HSF1 binding to the enhancer region in endothelial cells was observed under disturbed flow compared with unidirectional flow. CALCRL knockdown and variant perturbation experiments indicated the role of CALCRL in mediating eNOS (endothelial nitric oxide synthase), APLN (apelin), angiopoietin, prostaglandins, and EDN1 (endothelin-1) signaling pathways leading to a decrease in cell proliferation, tube formation, and NO production. CONCLUSIONS: Overall, our results demonstrate the existence of an endothelial-specific HSF (heat shock factor)-regulated transcriptional enhancer that mediates CALCRL expression. A better understanding of CALCRL gene regulation and the role of single-nucleotide polymorphisms in the modulation of CALCRL expression could provide important steps toward understanding the genetic regulation of shear stress signaling responses.
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Proteína Semelhante a Receptor de Calcitonina , Doença da Artéria Coronariana , Células Endoteliais , Elementos Facilitadores Genéticos , Polimorfismo de Nucleotídeo Único , Estresse Mecânico , Humanos , Células Endoteliais/metabolismo , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Proteína Semelhante a Receptor de Calcitonina/genética , Proteína Semelhante a Receptor de Calcitonina/metabolismo , Fatores de Transcrição de Choque Térmico/genética , Fatores de Transcrição de Choque Térmico/metabolismo , Mecanotransdução Celular , Células Cultivadas , Regulação da Expressão Gênica , Ligação Proteica , Predisposição Genética para Doença , Sítios de LigaçãoRESUMO
The gas-phase formation of new particles less than 1 nm in size and their subsequent growth significantly alters the availability of cloud condensation nuclei (CCN, >30-50 nm), leading to impacts on cloud reflectance and the global radiative budget. However, this growth cannot be accounted for by condensation of typical species driving the initial nucleation. Here, we present evidence that nucleated iodine oxide clusters provide unique sites for the accelerated growth of organic vapors to overcome the coagulation sink. Heterogeneous reactions form low-volatility organic acids and alkylaminium salts in the particle phase, while further oligomerization of small α-dicarbonyls (e.g., glyoxal) drives the particle growth. This identified heterogeneous mechanism explains the occurrence of particle production events at organic vapor concentrations almost an order of magnitude lower than those required for growth via condensation alone. A notable fraction of iodine associated with these growing particles is recycled back into the gas phase, suggesting an effective transport mechanism for iodine to remote regions, acting as a "catalyst" for nucleation and subsequent new particle production in marine air.
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OBJECTIVE: To compare the efficacy and safety of relocating the lower pole stones to a favorable pole during flexible ureteroscopy with in situ lithotripsy for the treatment of 10-20 mm lower pole stone (LPS). METHODS: This study was a prospective analysis of patient outcomes who underwent an FURS procedure for the treatment of 10-20 mm lower pole renal stones from January 2020 to November 2022. The patients were randomized into a relocation group or in situ group. The LPSs were relocated into a calyx, during lithotripsy in the relocation group was performed, whereas the in situ group underwent FURS without relocation. All the procedures were performed by the same surgeon. The patients' demographic data, stone characteristics, perioperative parameters and outcomes, stone-free rate (SFR), complications, and overall costs were assessed retrospectively. RESULTS: A total of 90 patients were enrolled and analyzed in this study (45 per group) with no significant differences between the two groups in terms of age, gender, BMI, diabetes, hypertension, stone size, number, laterality, composition, and density. The mean operation time, total energy consumption, postoperative stay, and complications were similar between the groups. Both groups had similar SFR at 1 day postoperative follow-up (p = 0.091), while the relocation group achieved significantly higher SFR 3 months later (97.8% vs 84.4%, p = 0.026). The relocation group also had a significantly higher WisQol score than the in situ group (126.98 vs 110.18, p < 0.001). CONCLUSION: A satisfactory SFR with a relatively low complication rate was achieved by the relocation technique during the FURS procedure.
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Cálculos Renais , Litotripsia a Laser , Litotripsia , Humanos , Ureteroscopia/efeitos adversos , Ureteroscopia/métodos , Estudos Retrospectivos , Litotripsia a Laser/métodos , Resultado do Tratamento , Cálculos Renais/cirurgia , Litotripsia/efeitos adversosRESUMO
Aqueous-phase reactions of α-dicarbonyls with amines or ammonium have been identified as important sources of secondary brown carbon (BrC). However, the kinetics of BrC formation and the effects of pH are still not very clear. In this study, the kinetics of BrC formation by aqueous reactions of α-dicarbonyls (glyoxal and methylglyoxal) with ammonium, amino acids, or alkylamines in bulk solution at different pH values are investigated. Our results reveal pH-parameterized BrC production rate constants, kBrCII (m-1 [M]-2 s-1), based on the light absorption between 300 and 500 nm: log10(kBrCII) = (1.0 ± 0.1) × pH - (7.4 ± 1.0) for reactions with glyoxal and log10(kBrCII) = (1.0 ± 0.1) × pH - (6.3 ± 0.9) for reactions with methylglyoxal. The linear slopes closing to 1.0 indicate that BrC formation is governed by the nitrogen nucleophilic addition pathway. Consequently, the absorptivities of the produced BrC increase exponentially with the increase of pH. BrC from reactions with methylglyoxal at higher pH (≥6.5) exhibits optical properties comparable to BrC from biomass burning or coal combustion, categorized as the "weakly" absorbing BrC, while BrC from reactions with methylglyoxal at lower pH (<6.0) or reactions with glyoxal (pH 5.0-7.0) falls into the "very weakly" absorbing BrC. The pH-dependent BrC feature significantly affects the solar absorption ability of the produced BrC and thus the atmospheric photochemical processes, e.g., BrC produced at pH 7.0 absorbs 14-16 times more solar power compared to that at pH 5.0, which in turn could lead to a decrease of 1 order of magnitude in the photolysis rate constants of O3 and NO2.
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Poluentes Atmosféricos , Compostos de Amônio , Aldeído Pirúvico/química , Fotoquímica , Carbono , Aerossóis/análise , Aminas , Glioxal , Água/química , Concentração de Íons de HidrogênioRESUMO
Volatility of organic aerosols (OAs) significantly influences new particle formation and the occurrence of particulate air pollution. However, the relationship between the volatility of OA and the level of particulate air pollution (i.e., particulate matter concentration) is not well understood. In this study, we compared the chemical composition (identified by an ultrahigh-resolution Orbitrap mass spectrometer) and volatility (estimated based on a predeveloped parametrization method) of OAs in urban PM2.5 (particulate matter with aerodynamic diameter ≤ 2.5 µm) samples from seven German and Chinese cities, where the PM2.5 concentration ranged from a light (14 µg m-3) to heavy (319 µg m-3) pollution level. A large fraction (71-98%) of compounds in PM2.5 samples were attributable to intermediate-volatility organic compounds (IVOCs) and semivolatile organic compounds (SVOCs). The fraction of low-volatility organic compounds (LVOCs) and extremely low-volatility organic compounds (ELVOCs) decreased from clean (28%) to heavily polluted urban regions (2%), while that of IVOCs increased from 34 to 62%. We found that the average peak area-weighted volatility of organic compounds in different cities showed a logarithmic correlation with the average PM2.5 concentration, indicating that the volatility of urban OAs increases with the increase of air pollution level. Our results provide new insights into the relationship between OA volatility and PM pollution levels and deepen the understanding of urban air pollutant evolution.
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Aerossóis , Poluentes Atmosféricos , Poluição do Ar , Espectrometria de Massas , Material Particulado , Material Particulado/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Volatilização , Compostos Orgânicos/análise , China , Compostos Orgânicos Voláteis/análiseRESUMO
Key stages in people's lives have particular relevance for their health; the life-course approach stresses the importance of these stages. Here, we applied a life-course approach to analyze the health risks associated with PM2.5-bound elements, which were measured at three sites with varying environmental conditions in eastern China. Road traffic was found to be the primary source of PM2.5-bound elements at all three locations, but coal combustion was identified as the most important factor to induce both cancer risk (CR) and noncancer risk (NCR) across all age groups due to the higher toxicity of elements such as As and Pb associated with coal. Nearly half of NCR and over 90% of CR occurred in childhood (1-6 years) and adulthood (>18 years), respectively, and females have slightly higher NCR and lower CR than males. Rural population is found to be subject to the highest health risks. Synthesizing previous relevant studies and nationwide PM2.5 concentration measurements, we reveal ubiquitous and large urban-rural environmental exposure disparities over China.
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Poluentes Atmosféricos , Material Particulado , Masculino , Feminino , Humanos , Material Particulado/análise , Poluentes Atmosféricos/análise , Estações do Ano , Monitoramento Ambiental , Medição de Risco , China/epidemiologia , Carvão Mineral/análiseRESUMO
Many types of living plants release gaseous trimethylamine (TMA), making it a potentially important contributor to new particle formation (NPF) in remote areas. However, a panoramic view of the importance of forest biogenic TMA at the regional scale is lacking. Here, we pioneered nationwide mobile measurements of TMA across a transect of contiguous farmland in eastern China and a transect of subtropical forests in southern China. In contrast to the farmland route, TMA concentrations measured during the subtropical forest route correlated significantly with isoprene, suggesting potential TMA emissions from leaves. Our high time-resolved concentrations obtained from a weak photo-oxidizing atmosphere reflected freshly emitted TMA, indicating the highest emission intensity from irrigated dryland (set as the baseline of 10), followed by paddy field (7.1), subtropical evergreen forests (5.9), and subtropical broadleaf and mixed forests (4.3). Extrapolating their proportions roughly to China, subtropical forests alone, which constitute half of the total forest area, account for nearly 70% of the TMA emissions from the nation's total farmland. Our estimates, despite the uncertainties, take the first step toward large-scale assessment of forest biogenic amines, highlighting the need for observational and modeling studies to consider this hitherto overlooked source of TMA.
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Florestas , Metilaminas , Fazendas , China , SoloRESUMO
Secondary organic aerosol (SOA) formation from gasoline vehicles spanning a wide range of emission types was investigated using an oxidation flow reactor (OFR) by conducting chassis dynamometer tests. Aided by advanced mass spectrometric techniques, SOA precursors, including volatile organic compounds (VOCs) and intermediate/semivolatile organic compounds (I/SVOCs), were comprehensively characterized. The reconstructed SOA produced from the speciated VOCs and I/SVOCs can explain 69% of the SOA measured downstream of an OFR upon 0.5-3 days' OH exposure. While VOCs can only explain 10% of total SOA production, the contribution from I/SVOCs is 59%, with oxygenated I/SVOCs (O-I/SVOCs) taking up 20% of that contribution. O-I/SVOCs (e.g., benzylic or aliphatic aldehydes and ketones), as an obscured source, account for 16% of total nonmethane organic gas (NMOG) emission. More importantly, with the improvement in emission standards, the NMOG is effectively mitigated by 35% from China 4 to China 6, which is predominantly attributed to the decrease of VOCs. Real-time measurements of different NMOG components as well as SOA production further reveal that the current emission control measures, such as advances in engine and three-way catalytic converter (TWC) techniques, are effective in reducing the "light" SOA precursors (i.e., single-ring aromatics) but not for the I/SVOC emissions. Our results also highlight greater effects of O-I/SVOCs to SOA formation than previously observed and the urgent need for further investigation into their origins, i.e., incomplete combustion, lubricating oil, etc., which requires improvements in real-time molecular-level characterization of I/SVOC molecules and in turn will benefit the future design of control measures.
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Aerossóis , Gasolina , Emissões de Veículos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/química , Compostos Orgânicos/químicaRESUMO
BACKGROUND Clinical training for allied health trainees (AHTs) and postgraduate-year (PGY) doctors needed to go online during the outbreak of coronavirus disease 2019 (COVID-19), which may have caused academic stress and consequent outcomes among this cohort. MATERIAL AND METHODS To evaluate academic-related stress, clinical confidence, psychological distress, and insomnia, an online survey-based study was conducted among Taiwanese AHTs and PGY doctors between July and December, 2022, during the COVID-19 pandemic. The survey included the 21-item Depression, Anxiety, and Stress Scale (DASS-21), the Insomnia Severity Index (ISI), and self-designed questions. It was distributed using convenience sampling and snowball sampling and was completed by 522 participants. RESULTS Structural equational modelling showed that academic stress was negatively associated with clinical confidence (standardized coefficient [ß]=-0.382, p<0.001). Clinical confidence was negatively associated with psychological distress (ß=-0.397, p<0.001), which was associated with insomnia (ß=0.648, p<0.001). Additionally, clinical confidence and psychological distress were the significant mediators. Results indicated that higher academic stress was associated with higher level of insomnia via the mediation of clinical confidence and psychological distress. CONCLUSIONS Academic stress related to changes in clinical training may have led to insomnia among AHTs and PGY doctors during the pandemic. Factors to reduce academic stress should be investigated to promote good mental health while providing sufficient clinical training, especially during events that can cause increased stress (eg, epidemics, pandemics).
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COVID-19 , Distúrbios do Início e da Manutenção do Sono , Estresse Psicológico , Ideação Suicida , Humanos , COVID-19/psicologia , COVID-19/epidemiologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Taiwan/epidemiologia , Masculino , Feminino , Adulto , Estresse Psicológico/psicologia , Inquéritos e Questionários , SARS-CoV-2 , Ansiedade/psicologia , Pandemias , Depressão/psicologia , Corpo Clínico Hospitalar/psicologiaRESUMO
Vascular disease is a leading cause of morbidity and mortality in the United States and globally. Pathological vascular remodeling, such as atherosclerosis and stenosis, largely develop at arterial sites of curvature, branching, and bifurcation, where disturbed blood flow activates vascular endothelium. Current pharmacological treatments of vascular complications principally target systemic risk factors. Improvements are needed. We previously devised a targeted polyelectrolyte complex micelle to deliver therapeutic nucleotides to inflamed endothelium in vitro by displaying the peptide VHPKQHR targeting vascular cell adhesion molecule 1 (VCAM-1) on the periphery of the micelle. This paper explores whether this targeted nanomedicine strategy effectively treats vascular complications in vivo. Disturbed flow-induced microRNA-92a (miR-92a) has been linked to endothelial dysfunction. We have engineered a transgenic line (miR-92aEC-TG /Apoe-/- ) establishing that selective miR-92a overexpression in adult vascular endothelium causally promotes atherosclerosis in Apoe-/- mice. We tested the therapeutic effectiveness of the VCAM-1-targeting polyelectrolyte complex micelles to deliver miR-92a inhibitors and treat pathological vascular remodeling in vivo. VCAM-1-targeting micelles preferentially delivered miRNA inhibitors to inflamed endothelial cells in vitro and in vivo. The therapeutic effectiveness of anti-miR-92a therapy in treating atherosclerosis and stenosis in Apoe-/- mice is markedly enhanced by the VCAM-1-targeting polyelectrolyte complex micelles. These results demonstrate a proof of concept to devise polyelectrolyte complex micelle-based targeted nanomedicine approaches treating vascular complications in vivo.
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Aterosclerose/metabolismo , Células Endoteliais/metabolismo , MicroRNAs/metabolismo , Animais , Aterosclerose/genética , Corantes Fluorescentes , Regulação da Expressão Gênica , Humanos , Inflamação , Masculino , Camundongos , Camundongos Knockout para ApoE , Camundongos Transgênicos , Micelas , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Farmacologia em Rede , Polieletrólitos , Regulação para Cima , Molécula 1 de Adesão de Célula VascularRESUMO
The Hindu Kush high-altitude regions of Pakistan are currently experiencing severe consequences as a result of global warming. In this sense, increasing soil erosion and the quick melting of glaciers are two particularly evident effects. In such a scenario, understanding long-term temperature changes is crucial for making accurate forecasts about how the Hindu Kush region may experience regional temperature changes in the future. In this study, the climate tree-ring width (TRW) analysis designated a positive and significant correlation (r = 0.622, p < 0.001) between the TRW chronology and the June to September (summer) mean maximum temperature (MMT). Using the tree-ring width of Pinus wallichiana A. B. Jackson, we reconstructed summer temperatures in the Hindu Kush region from 1790 CE. Statistical analysis showed that the reconstruction model has explained 38.7% of the climate variance during the instrumental period of 1967 to 2018 CE. Five extremely warm summer periods (≥ 4 years; before the instrumental period 1967-2018 CE) of 1804-1830, 1839-1862, 1876-1879, 1905-1910, 1923-1935 CE, and six cold summer periods of 1790-1803, 1832-1838, 1863-1875, 1880-1904, 1911-1922, and 1936-1945 CE have been observed during the past 229 years. Individually, the year 1856 CE experienced severe warmth (31.85 °C), whereas 1794 CE was relatively cooler (29.60 °C). The spectral multi-taper method (MTM) shows significant (p < 0.05) cycles, which take place about every 9.3, 5.7, 4.2, and 3.6 years. In particular, the 9.3-year cycle, which closely aligns with the 11-year solar activity cycle, suggests a potential correlation between solar activity and local temperature fluctuations. Moreover, our reconstruction demonstrates a significant degree of consistency when compared to actual climate data and regional temperature reconstruction series, reporting a strong logic of trust in the reliability and accuracy of our findings. This evidence reaffirms that our reconstruction shows significant and dependable regional temperature signals, notably being representative for the Hindu Kush region.
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Estações do Ano , Temperatura , Árvores , Paquistão , História do Século XIX , História do Século XX , Pinus , História do Século XVIIIRESUMO
OBJECTIVE: The purpose of this study was to evaluate the yield, viability, clinical safety, and efficacy of the stromal vascular fraction (SVF) separated with a new protocol with all clinical-grade drugs. MATERIALS AND METHODS: SVF cells were isolated from lipoaspirate obtained from 13 participants aged from 30 to 56 years by using a new clinical protocol and the laboratory protocol. The cell yield, viability, morphology, mesenchymal stem cell (MSC) surface marker expression, and differentiation abilities of the SVF cells harvested from the two protocols were compared. Furthermore, three related clinical trials were conducted to verify the safety and efficiency of SVF cells isolated by the new clinical protocol. RESULTS: There were no significant differences in the yield, viability, morphology, and differentiation potential of the SVFs isolated with the clinical protocol and laboratory protocol. Adipose-derived mesenchymal stem cell (ASC) surface marker expression, including that of CD14, CD31, CD44, CD90, CD105, and CD133, was consistent between the two protocols. Clinical trials have demonstrated the effectiveness of the SVF isolated with the new clinical protocol in improving skin grafting, promoting mechanical stretch-induced skin regeneration and improving facial skin texture. No complications occurred. CONCLUSION: SVF isolated by the new clinical protocol had a noninferior yield and viability to that of the SVF separated by the laboratory protocol. SVFs obtained by the new protocol can be safely and effectively applied to improve skin grafting, promote mechanical stretch-induced skin regeneration, and improve facial skin texture. TRIAL REGISTRATION: The trials were registered with the ClinicalTrials.gov (NCT03189628), the Chinese Clinical Trial Registry (ChiCTR2000039317), and the ClinicalTrials.gov (NCT02546882). All the three trials were not patient-funded trials. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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The ß3-adrenoceptor agonist mirabegron is available for the treatment of storage symptoms of overactive bladder, including frequency, urgency, and incontinence. The off-target effects of mirabegron include binding to α1-adrenoceptors, which are central in the treatment of voiding symptoms. Here, we examined the structure-function relationships in the binding of mirabegron to a cryo-electron microscopy structure of α1A. The binding was simulated by docking mirabegron to a 3D structure of a human α1A-adrenoceptor (7YMH) using Autodock Vina. The simulations identified two binding states: slope orientation involving 10 positions and horizontal binding to the receptor surface involving 4 positions. No interactions occurred with positions constituting the α1A binding pocket, including Asp-106, Ser-188, or Phe-312, despite the positioning of the phenylethanolamine moiety in transmembrane regions close to the binding pocket by contact with Phe-288, -289, and Val-107. Contact with the unique positions of α1A included the transmembrane Met-292 during slope binding and exosite Phe-86 during horizontal binding. Exosite binding in slope orientation involved contact of the anilino part, rather than the aminothiazol end, to Ile-178, Ala-103, and Asn-179. In conclusion, contact with Met-292 and Phe-86, which are unique positions of α1A, accounts for mirabegron binding to α1A. Because of its lack of interactions with the binding pocket, mirabegron has lower affinity compared to α1A-blockers and no effects on voiding symptoms.
Assuntos
Acetanilidas , Agonistas de Receptores Adrenérgicos beta 3 , Simulação de Acoplamento Molecular , Ligação Proteica , Receptores Adrenérgicos alfa 1 , Tiazóis , Acetanilidas/química , Acetanilidas/farmacologia , Acetanilidas/metabolismo , Tiazóis/química , Tiazóis/farmacologia , Tiazóis/metabolismo , Humanos , Relação Estrutura-Atividade , Receptores Adrenérgicos alfa 1/metabolismo , Receptores Adrenérgicos alfa 1/química , Agonistas de Receptores Adrenérgicos beta 3/farmacologia , Agonistas de Receptores Adrenérgicos beta 3/química , Agonistas de Receptores Adrenérgicos beta 3/metabolismo , Sítios de Ligação , Ligantes , Microscopia CrioeletrônicaRESUMO
The clinical data of coronary heart disease(CHD) patients treated in the First Affiliated Hospital of Guangzhou University of Chinese Medicine and Shenzhen Hospital of Integrated Traditional Chinese and Western Medicine from January 2022 to March 2023 were retrospectively collected. This study involved the descriptive analysis of demographic characteristics, clinical symptoms, and tongue and pulse features. The χ~2 test was conducted to analyze the distribution of syndrome elements and their combinations at diffe-rent stages of CHD, so as to reveal the clinical characteristics and syndrome patterns at various pathological stages of CHD. This study extracted 28 symptom entries, 10 tongue manifestation entries, and 7 pulse manifestation entries, summarized the 5 main disease locations of the heart, lung, liver, spleen, and kidney, and the 8 main disease natures of blood stasis, phlegm turbidity, Qi stagnation, heat(fire), fluid retention, Qi deficiency, Yin deficiency, and Yang deficiency and 8 combinations of disease natures. The χ~2 test showed significant differences in the distribution of syndrome elements including the lung, liver, spleen, kidney, blood stasis, heat(fire), Qi stagnation, heat syndrome, water retention, Qi deficiency, Yin deficiency, and Yang deficiency between different disease stages. Specifically, the liver, blood stasis, heat(fire), and Qi stagnation accounted for the highest proportion during unstable stage, and the lung, spleen, kidney, water retention, Qi deficiency, Yin deficiency, and Yang deficiency accounted for the highest proportion at the end stage. The distribution of Qi deficiency varied in the different time periods after percutaneous coronary intervention(PCI). As shown by the χ~2 test of the syndrome elements combination, the distribution of single disease location, multiple disease locations, single disease nature, double disease natures, multiple natures, excess syndrome, and mixture of deficiency and excess varied significantly at different stages of CHD. Specifically, single disease location, single disease nature, and excess syndrome accounted for the highest proportion during the stable stage, and double disease natures accounted for the highest proportion during the unstable stage. Multiple disease locations, multiple disease natures, and mixture of deficiency and excess accounted for the highest proportion during the end stage. In conclusion, phlegm turbidity and blood stasis were equally serious during the stable stage, and a pathological mechanism caused by blood stasis and toxin existed during the unstable stage. The overall Qi deficiency worsened after PCI, and the end stage was accompanied by the Yin and Yang damage and the aggravation of water retention. There were significant differences in the distribution of clinical characteristics and syndrome elements at different stages of CHD. The pathological process of CHD witnessed the growth and decline of deficiency and excess and the combination of phlegm turbidity and blood stasis, which constituted the basic pathogenesis.
Assuntos
Doença das Coronárias , Insuficiência Cardíaca , Intervenção Coronária Percutânea , Humanos , Medicina Tradicional Chinesa , Deficiência da Energia Yang , Deficiência da Energia Yin , Estudos Transversais , Estudos Retrospectivos , Doença das Coronárias/diagnóstico , Doença das Coronárias/epidemiologia , Síndrome , ÁguaRESUMO
Specificity protein 1 (SP1), hypoxia-inducible factor 1 (HIF-1), and MYC are important transcription factors (TFs). SP1, a constitutively expressed housekeeping gene, regulates diverse yet distinct biological activities; MYC is a master regulator of all key cellular activities including cell metabolism and proliferation; and HIF-1, whose protein level is rapidly increased when the local tissue oxygen concentration decreases, functions as a mediator of hypoxic signals. Systems analyses of the regulatory networks in cancer have shown that SP1, HIF-1, and MYC belong to a group of TFs that function as master regulators of cancer. Therefore, the contributions of these TFs are crucial to the development of cancer. SP1, HIF-1, and MYC are often overexpressed in tumors, which indicates the importance of their roles in the development of cancer. Thus, proper manipulation of SP1, HIF-1, and MYC by appropriate agents could have a strong negative impact on cancer development. Under these circumstances, these TFs have naturally become major targets for anticancer drug development. Accordingly, there are currently many SP1 or HIF-1 inhibitors available; however, designing efficient MYC inhibitors has been extremely difficult. Studies have shown that SP1, HIF-1, and MYC modulate the expression of each other and collaborate to regulate the expression of numerous genes. In this review, we provide an overview of the interactions and collaborations of SP1, HIF1A, and MYC in the regulation of various cancer-related genes, and their potential implications in the development of anticancer therapy.
RESUMO
Methylsiloxanes have gained growing attention as emerging pollutants due to their toxicity to organisms. As man-made chemicals with no natural source, most research to date has focused on volatile methylsiloxanes from personal care or household products and industrial processes. Here, we show that methylsiloxanes can be found in primary aerosol particles emitted by vehicles based on aerosol samples collected in two tunnels in São Paulo, Brazil. The aerosol samples were analyzed with thermal desorption-proton transfer reaction-mass spectrometry (TD-PTR-MS), and methylsiloxanes were identified and quantified in the mass spectra based on the natural abundance of silicon isotopes. Various methylsiloxanes and derivatives were found in aerosol particles from both tunnels. The concentrations of methylsiloxanes and derivatives ranged 37.7-377 ng m-3, and the relative fractions in organic aerosols were 0.78-1.9%. The concentrations of methylsiloxanes exhibited a significant correlation with both unburned lubricating oils and organic aerosol mass. The emission factors of methylsiloxanes averaged 1.16 ± 0.59 mg kg-1 of burned fuel for light-duty vehicles and 1.53 ± 0.37 mg kg-1 for heavy-duty vehicles. Global annual emissions of methylsiloxanes in vehicle-emitted aerosols were estimated to range from 0.0035 to 0.0060 Tg, underscoring the significant yet largely unknown potential for health and climate impacts.