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Background: Gastric cancer (GC) is the most common malignant tumor and ranks third in the world. LncRNA H19 (H19), one of the members of lncRNA, is overexpressed in various tumors. However, many undetermined molecular mechanisms by which H19 promotes GC progression still need to be further investigated. Methodology. A series of experiments was used to confirm the undetermined molecular mechanism including wound healing and transwell assays. Key Results. In this study, a significant upregulation of H19 expression was detected in GC cells and tissues. The poor overall survival was observed in GC patient with high H19 expression. Overexpression of H19 promoted the migration of GC cells, while knockdown of H19 significantly inhibited cell migration. Moreover, miR-148a-3p had a certain negative correlation with H19. Luciferase reporter assay confirmed that H19 could directly bind to miR-148a-3p. As expected, miR-148a mimics inhibited cell migration and invasion induced by H19 overexpression. The above findings proved that H19 functions as a miRNA sponge and verified that miR-148a-3p is the H19-associated miRNA in GC. We also confirmed that SOX-12 expression was upregulated in GC patient's samples. SOX-12 expression was positively correlated with expression of H19 and was able to directly bind to miR-148a-3p. Importantly, in vitro wound healing assay showed that knockout of SOX-12 could reverse the promoting effect of H19 overexpression on cell migration. Conclusion: In conclusion, H19 has certain application value in the diagnosis and prognosis of GC. Specifically, H19 accelerates GCs to migration and metastasis by miR-138a-3p/SOX-12 axis.
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Movimento Celular , Regulação Neoplásica da Expressão Gênica , MicroRNAs , Metástase Neoplásica , RNA Longo não Codificante , Fatores de Transcrição SOXC , Neoplasias Gástricas , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Neoplasias Gástricas/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Movimento Celular/genética , Linhagem Celular Tumoral , Fatores de Transcrição SOXC/metabolismo , Fatores de Transcrição SOXC/genética , Regulação para Cima/genética , Masculino , Pessoa de Meia-Idade , Feminino , Invasividade Neoplásica , Sequência de BasesRESUMO
Aspergillus flavus is a notorious fungus that contaminates food crops with toxic aflatoxins, posing a serious threat to human health and the agricultural economy. To overcome the inadequacy of traditional control methods and meet consumer preferences for natural-sources additives, there is an urgent demand for novel biocontrol agents that are safe and efficient. This study aims to investigate the antifungal properties of a novel antifungal agent derived from the biologically safe Lactiplantibacillus plantarum WYH. Firstly, antifungal peptides (AFPs) with a molecular weight of less than 3kD, exhibiting remarkable temperature stability and effectively retarding fungal growth in a dose-dependent manner specifically against A. flavus, were concentrated from the fermentation supernatant of L. plantarum WYH and were named as AFPs-WYH. Further analysis demonstrated that AFPs-WYH might exert antifungal effects through the induction of oxidative stress, disruption of mitochondrial function, alteration of membrane permeability, and cell apoptosis in A. flavus. To further validate our findings, a transcriptomics analysis was conducted on A. flavus treated with 2 and 5 mg/mL of AFPs-WYH, which elucidated the potential effect of AFPs-WYH administration on the regulation of genes involved in impairing fungal development and preventing aflatoxin biosynthesis pathways. Overall, AFPs-WYH reduced the A. flavus proliferation and affected the AFB1 biosynthesis, exhibiting a promising potential for food industry applications as a biopreservative and biocontrol agent.
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Antifúngicos , Aspergillus flavus , Aspergillus flavus/efeitos dos fármacos , Aspergillus flavus/crescimento & desenvolvimento , Antifúngicos/farmacologia , Agentes de Controle Biológico/farmacologia , Contaminação de Alimentos/prevenção & controle , Lactobacillus plantarum/metabolismo , Fermentação , Peptídeos/farmacologia , Aflatoxinas/biossíntese , Estresse Oxidativo/efeitos dos fármacosRESUMO
BACKGROUND: The strategy for preventing colorectal cancer is screening by colonoscopy, which offers a direct way for detection and removal of adenomatous polyps (APs). American College of Gastroenterology guidelines recommend that people aged ≥ 45 years should undergo colonoscopy; however, how to deal with people aged ≤ 45 years is still unknown. AIM: To compare the prevalence of APs and high-grade neoplasia between the left and right colon in patients ≤ 45 years. METHODS: A retrospective observational study was conducted at a single tertiary III hospital in China. This study included patients aged 18-45 years with undergoing initial colonoscopy dissection and pathological diagnosis AP or high-grade neoplasia between February 2014 and January 2021. The number of APs in the entire colon while screening and post-polypectomy surveillance in following 1-3 years were evaluated. RESULTS: A total of 3053 cases were included. The prevalence of APs in the left and right colon was 55.0% and 41.6%, respectively (OR 1.7, 95%CI 1.6-2.4; P < 0.05). For APs with high-grade neoplasia, the prevalence was 2.7% and 0.9%, respectively (OR 3.0, 95%CI 2.0-4.6; P < 0.05). Therefore, the prevalence of APs and high-grade neoplasia in the left colon was significantly higher than in the right colon in patients aged ≤ 45 years. There were 327 patients who voluntarily participated in post-polypectomy surveillance in following 1-3 years, and APs were found in 216 cases (66.1%); 170 cases had 1-3 polyps (52.0%) and 46 cases had > 3 polyps (14.1%; OR 0.3, 95%CI 0.1-0.6; P < 0.05). CONCLUSION: This study suggests that flexible sigmoidoscopy would be an optimal approach for initial screening in people aged ≤ 45 years and would be a more cost-effective and safe strategy.
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Cyclic peptides with cyclophane linkers are an attractive compound type owing to the fine-tuned rigid three-dimensional structures and unusual biophysical features. Cytochrome P450 enzymes are capable of catalyzing not only the C-C and C-O oxidative coupling reactions found in vancomycin and other nonribosomal peptides (NRPs), but they also exhibit novel catalytic activities to generate cyclic ribosomally synthesized and post-translationally modified peptides (RiPPs) through cyclophane linkage. To discover more P450-modified multicyclic RiPPs, we set out to find cryptic and unknown P450-modified RiPP biosynthetic gene clusters (BGCs) through genome mining. Synergized bioinformatic analysis reveals that P450-modified RiPP BGCs are broadly distributed in bacteria and can be classified into 11â classes. Focusing on two classes of P450-modified RiPP BGCs where precursor peptides contain multiple conserved aromatic amino acid residues, we characterized 11 novel P450-modified multicyclic RiPPs with different cyclophane linkers through heterologous expression. Further mutation of the key ring-forming residues and combinatorial biosynthesis study revealed the order of bond formation and the specificity of P450s. This study reveals the functional diversity of P450 enzymes involved in the cyclophane-containing RiPPs and indicates that P450 enzymes are promising tools for rapidly obtaining structurally diverse cyclic peptide derivatives.
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Produtos Biológicos , Ciclofanos , Peptídeos/química , Peptídeos Cíclicos/química , Biologia Computacional/métodos , Sistema Enzimático do Citocromo P-450/metabolismo , Processamento de Proteína Pós-Traducional , Produtos Biológicos/químicaRESUMO
Solar-driven interfacial evaporation (SDIE) stands out as a prospective technology for freshwater production, playing a significant role in mitigating global water scarcity. Herein, a cyclodextrin polymer/chitosan composite aerogel (PPy-La/Al@CDP-CS) with vertically aligned channels was prepared as a solar evaporator for efficient solar steam generation. The vertically aligned pore structure, achieved through directional freezing assisted by liquid nitrogen, not only improves water transport during evaporation but also enhances light absorption through multiple reflections of sunlight within the pores. The polypyrrole particles sprayed on the surface of the aerogel acted as a light-absorbing layer, resulting in an impressive absorbance of 98.15 % under wetting conditions. The aerogel has an evaporation rate of 1.85 kg m-2 h-1 under 1 kW m-2 irradiation. Notably, the vertical pore structure of the aerogel allows it to exhibit excellent evaporation performance and salt resistance even in highly concentrated salt solutions. Furthermore, this aerogel is an excellent solar-driven interfacial evaporator for purifying seawater and fluoride-containing wastewater. This photothermal aerogel has the advantages of excellent performance, low cost, and environmental friendliness, and thus this work provides a new approach to the design and fabrication of solar photothermal materials for water treatment.
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Celulose , Quitosana , Ciclodextrinas , Polímeros , Pirróis , Porosidade , Estudos ProspectivosRESUMO
Cyclization of linear peptides is an effective strategy to convert flexible molecules into rigid compounds, which is of great significance for enhancing the peptide stability and bioactivity. Despite significant advances in the past few decades, Nature and chemists' ability to macrocyclize linear peptides is still quite limited. P450 enzymes have been reported to catalyze macrocyclization of peptides through cross-linkers between aromatic amino acids with only three examples. Herein, we developed an efficient workflow for the identification of P450-modified RiPPs in bacterial genomes, resulting in the discovery of a large number of P450-modified RiPP gene clusters. Combined with subsequent expression and structural characterization of the products, we have identified 11 novel P450-modified RiPPs with different cross-linking patterns from four distinct classes. Our results greatly expand the structural diversity of P450-modified RiPPs and provide new insights and enzymatic tools for the production of cyclic peptides.
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Produtos Biológicos , Ribossomos , Ribossomos/metabolismo , Peptídeos/química , Peptídeos Cíclicos/química , Sistema Enzimático do Citocromo P-450/metabolismo , Processamento de Proteína Pós-Traducional , Produtos Biológicos/químicaRESUMO
Hematopoietic stem and progenitor cells (HSPCs) could be differentiated into mature myeloid and lymphoid cells, maintaining the requirements of immune cells. Atherosclerosis and ulcerative colitis (UC) drive HSPC homeostasis destruction, which triggers expansive HSPC proliferation and Ly6Chi monocyte production, contributing to aggravated inflammation. Vitisin A belongs to the anthocyanin derivatives with excellent stability and bioactivity in vitro. However, there is no report about the anti-inflammation of Vitisin A via reprogramming HSPC differentiation toward monocytes. In this study, we found that Vitisin A presents anti-inflammatory ability during the development of atherosclerosis and UC by depressing Ly6Chi monocyte production from bone marrow. This performance depended on restricted HSPC differentiation, which suggested that Vitisin A participated in monocyte generation and carried out the immunomodulation. Together, Vitisin A ameliorates inflammation during atherosclerosis and UC via the suppressed differentiation of HSPCs toward monocytes, which could be considered an ideal functional component with immunomodulatory effects.
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Aterosclerose , Medula Óssea , Humanos , Monócitos , Células-Tronco Hematopoéticas , Inflamação , Diferenciação CelularRESUMO
Tea is one of the most popular drinks in the world. Dark tea is a kind of post-fermented tea with unique sensory characteristics that is produced by the special fermentation of microorganisms. It contains many bioactive substances, such as tea polyphenols, theabrownin, tea polysaccharides, etc., which have been reported to be beneficial to human health. This paper reviewed the latest research on dark tea's potential in preventing and managing cancer, and the mechanisms mainly involved anti-oxidation, anti-inflammation, inhibiting cancer cell proliferation, inducing cancer cell apoptosis, inhibiting tumor metastasis, and regulating intestinal flora. The purpose of this review is to accumulate evidence on the anti-cancer effects of dark tea, the corresponding mechanisms and limitations of dark tea for cancer prevention and management, the future prospects, and demanding questions about dark tea's possible contributions as an anti-cancer adjuvant.
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Adjuvantes Imunológicos , Neoplasias , Humanos , Apoptose , Proliferação de Células , Fermentação , Chá , Neoplasias/prevenção & controleRESUMO
PURPOSE: To evaluate the incidence of malignancies in acromegaly and to identify risk factors for newly-diagnostic cancers, especially the excessive growth hormone (GH) and insulin-like growth factor-1 (IGF-1). METHODS: A retrospective cohort including 1738 consecutive hospitalized patients with acromegaly in a single referral center between 2012 and 2020 (mean follow-up 4.3 years). A gender- and age-matched case-control study (280 patients from the cohort) was performed for risk factor analysis. RESULTS: One hundred thirteen malignancies (67 diagnosed after acromegaly) were observed. The overall newly-diagnostic cancer risk of acromegaly was higher than the general population (standardized incidence ratio (SIR) 2.81; 95% CI 2.18-3.57). The risk of thyroid cancer (n = 33, SIR 21.42; 95% CI 13.74-30.08) and colorectal cancer (n = 8, SIR 3.17; 95% CI 1.37-6.25) was elevated. In the overall cohort, IGF-1 (ULN: 1.27 vs. 0.94, p = 0.057), GH (1.30 vs. 1.00 ng/ml, p = 0.12), and disease-controlled rate (34.9% vs. 45.9%, p = 0.203) at the last visit did not reach significance between patients with and without post-diagnostic cancer. In the case-control study, GH (1.80 vs. 0.90 ng/ml, p = 0.018) and IGF-1 (ULN: 1.27 vs. 0.91, p = 0.003) at the last visit were higher in patients with post-diagnostic cancers, with a lower disease-controlled rate. Elder age was a risk factor for cancer. Other metabolic comorbidities and the size of pituitary tumors were similar. CONCLUSION: The risk of malignancies, especially thyroid cancer, was increased in patients with acromegaly in our center. More cancer screening should be considered when managing acromegaly, especially in patients with higher posttreatment GH and IGF-1.
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Acromegalia , Hormônio do Crescimento Humano , Neoplasias Hipofisárias , Neoplasias da Glândula Tireoide , Humanos , Idoso , Acromegalia/complicações , Acromegalia/epidemiologia , Acromegalia/metabolismo , Estudos Retrospectivos , Fator de Crescimento Insulin-Like I/metabolismo , Estudos de Casos e Controles , Incidência , População do Leste Asiático , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/etiologia , Fatores de RiscoRESUMO
Aspergillus fungi are widely used in the traditional fermentation of food products, so their safety risks and functions are worthy of investigation. In this study, one Aspergillus luchuensis YZ-1 isolated from Liubao tea was identified based on phylogenetic analyses of sequences of three genes coding for internal transcribed spacer 1 (ITS1), ß-tubulin (benA), and calmodulin (CaM). The results of hemolytic activity, DNase activity, cytotoxicity assay, and antibiotic resistance assay indicated that the strain is potentially safe. The excellent gastrointestinal fluid tolerance, acid tolerance, bile tolerance, auto-aggregation, co-aggregation, cell surface hydrophobicity, and adhesion to human colon adenocarcinoma (HT29) cell line were observed on analysis of the probiotic properties. Furthermore, the results of the antibacterial activity of A. luchuensis YZ-1 indicated that the strain had strong antagonistic effects against Gram-negative and Gram-positive bacteria as well as fungi. Simultaneously, the water extracts and 80% ethanolic extracts of A. luchuensis YZ-1 cells also showed strong ABTS, DPPH, and OH- scavenging ability. Taken together, our results suggest that A. luchuensis YZ-1 has desirable functional probiotic properties and can be proposed as a biocontrol agent in the food industry.
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BACKGROUND: Pregnancy in acromegaly is uncommon and still in debate for fear of tumor progression or potential threat to both mother and fetus's health. Besides, the data for pregnancy complications in uncontrolled acromegaly is limited. Thus, the objective of this study was to summarize pregnancy safety and disease courses after pregnancy in acromegalic patients and review their clinical characteristics based on disease activity in the literature. METHODS: An evaluation of eight acromegalic women from Peking Union Medical College Hospital (PUMCH) with 11 pregnancies was conducted. We also summarized a literature review of 82 disease-active pregnancies and 63 disease-controlled pregnancies with acromegaly. A second analysis was conducted to compare pregnancy courses and outcomes in different disease activities. RESULTS: Before pregnancy, all patients had macroadenomas and underwent pituitary surgery. Pregnancy occurred at a median of 6 years (4-10) after the diagnosis of acromegaly. Assisted reproductive therapy was needed in 42.9% of participants. No cases had a premature birth or congenital malformations. Biochemical control was achieved in 50% of females before pregnancy and 75% at the last follow-up after delivery. Data analysis showed no differences in the prevalence of gestational diabetes mellitus (GDM) or pregnancy-induced hypertension (PIH) between acromegaly-active or acromegaly-controlled groups. The GDM prevalence in patients diagnosed during pregnancy (33.3%) was higher than that in patients diagnosed before pregnancy (4.8%) (p = 0.001). CONCLUSION: Pregnancy without biochemical control in acromegaly and receiving medical treatment during pregnancy are not rare and generally safe for the fetus. There could be a higher prevalence of PIH in acromegalic pregnancies. The treatment of acromegaly and related complications can be managed with regular follow-up after pregnancy.
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Acromegalia , Diabetes Gestacional , Gravidez , Humanos , Feminino , Lactente , Acromegalia/complicações , Acromegalia/epidemiologia , China/epidemiologia , Família , Análise de Dados , Diabetes Gestacional/epidemiologiaRESUMO
Air pollution consisting of fine particulate matter (PM2.5) can induce or aggravate pulmonary inflammatory injury. Irisin has been shown to inhibit inflammation and help to protect against acute kidney, lung or brain injury. However, the role of irisin in lung inflammation after exposure to PM2.5 remains unclear. The aim of this study was to investigate the effect and molecular mechanism of irisin supplementation on in vitro and in vivo models of PM2.5-induced acute lung injuryï¼ALI). C57BL/6 mice and alveolar macrophage cell line (MH-S) were treated with PM2.5. Histopathological examination and FNDC5/ irisin immunofluorescence staining was performed on lung tissue sections. MH-S cell viability was determined by CCK-8 assay. The levels of Nod2, NF-κB p65 and NLRP3 were detected by qRT-PCR and western blotting. The levels of cytokines (IL-1ß, IL-18 and TNF-α) were detected by ELISA. PM2.5 exposure induced increased secretion of pro-inflammatory factors and activation of Nod2, NF-κB p65 and NLRP3 as well as endogenous levels of irisin. In vivo and in vitro inflammation was alleviated by irisin supplementation. Irisin significantly decreased IL-1ß, IL-18, and TNF-α production at both mRNA and protein level. Expression levels of Nod2, NF-κB p65, and NLRP3 were all significantly affected by irisin. In vivo the degree of pulmonary injury and inflammatory infiltration was weakened after irisin administration. In vitro, irisin could inhibit the activation of the NLRP3 inflammasome for a sustained period of 24 h, and its inhibitory ability was gradually enhanced. In conclusion, our findings indicate that irisin can modulate the inflammatory injury of lung tissue caused by PM2.5 through the Nod2/NF-κB signaling pathway, suggesting that irisin can be a candidate for the therapeutic or preventive intervention in acute lung inflammation.
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Lesão Pulmonar Aguda , Pneumonia , Camundongos , Animais , NF-kappa B/metabolismo , Material Particulado/efeitos adversos , Interleucina-18 , Fibronectinas/efeitos adversos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Camundongos Endogâmicos C57BL , Transdução de Sinais , Inflamação/metabolismoRESUMO
Irisin is a hormonelike myokine that regulates cell signaling pathways and exerts antiinflammatory effects. However, the specific molecular mechanisms involved in this process are currently unknown. The present study explored the role and mechanisms underlying the functions of irisin in alleviating acute lung injury (ALI). The present study used MHS, an established murine alveolar macrophagederived cell line, and a mouse model of lipopolysaccharide (LPS)inducedALI to examine the efficacy of irisin against ALI in vitro and in vivo, respectively. Fibronectin type III repeatcontaining protein/irisin was expressed in the inflamed lung tissue, but not in normal lung tissue. Exogenous irisin reduced alveolar inflammatory cell infiltration and proinflammatory factor secretion in mice following LPS stimulation. It also inhibited the polarization of M1type macrophages and promoted the repolarization of M2type macrophages, thus reducing the LPSinduced production and secretion of interleukin (IL)1ß, IL18 and tumor necrosis factorα. In addition, irisin reduced the release of the molecular chaperone heat shock protein 90 (HSP90), inhibited the formation of nucleotidebinding and oligomerization domainlike receptor protein 3 (NLRP3) inflammasome complexes, and decreased the expression of caspase1 and the cleavage of gasdermin D (GSDMD), leading to reduced pyroptosis and the accompanying inflammation. On the whole, the findings of the present study demonstrate that irisin attenuates ALI by inhibiting the HSP90/NLRP3/caspase1/GSDMD signaling pathway, reversing macrophage polarization and reducing the pyroptosis of macrophages. These findings provide a theoretical basis for understanding the role of irisin in the treatment of ALI and acute respiratory distress syndrome.
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Lesão Pulmonar Aguda , Macrófagos Alveolares , Animais , Camundongos , Macrófagos Alveolares/patologia , Piroptose , Fibronectinas , Proteína 3 que Contém Domínio de Pirina da Família NLR , Lipopolissacarídeos/farmacologia , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/patologia , Caspase 1 , InflamassomosRESUMO
BACKGROUND: Bivalent genes, of which promoters are marked by both H3K4me3 (trimethylation of histone H3 on lysine 4) and H3K27me3 (trimethylation of histone H3 on lysine 27), play critical roles in development and tumorigenesis. Monomethylation on lysine 4 of histone H3 (H3K4me1) is commonly associated with enhancers, but H3K4me1 is also present at promoter regions as an active bimodal or a repressed unimodal pattern. Whether the co-occurrence of H3K4me1 and bivalent marks at promoters plays regulatory role in development is largely unknown. RESULTS: We report that in the process of lineage differentiation, bivalent promoters undergo H3K27me3-H3K4me1 transition, the loss of H3K27me3 accompanies by bimodal pattern loss or unimodal pattern enrichment of H3K4me1. More importantly, this transition regulates tissue-specific gene expression to orchestrate the development. Furthermore, knockout of Eed (Embryonic Ectoderm Development) or Suz12 (Suppressor of Zeste 12) in mESCs (mouse embryonic stem cells), the core components of Polycomb repressive complex 2 (PRC2) which catalyzes H3K27 trimethylation, generates an artificial H3K27me3-H3K4me1 transition at partial bivalent promoters, which leads to up-regulation of meso-endoderm related genes and down-regulation of ectoderm related genes, thus could explain the observed neural ectoderm differentiation failure upon retinoic acid (RA) induction. Finally, we find that lysine-specific demethylase 1 (LSD1) interacts with PRC2 and contributes to the H3K27me3-H3K4me1 transition in mESCs. CONCLUSIONS: These findings suggest that H3K27me3-H3K4me1 transition plays a key role in lineage differentiation by regulating the expression of tissue specific genes, and H3K4me1 pattern in bivalent promoters could be modulated by LSD1 via interacting with PRC2.
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Pyranoanthocyanins have been reported to possess better chemical stability and bioactivities than monomeric anthocyanins in some aspects. The hypocholesterolemic activity of pyranoanthocyanins is unclear. In view of this, this study was conducted to compare the cholesterol-lowering activities of Vitisin A with the anthocyanin counterpart Cyanidin-3-O-glucoside(C3G) in HepG2 cells and to investigate the interaction of Vitisin A with the expression of genes and proteins associated with cholesterol metabolism. HepG2 cells were incubated with 40 µM cholesterol and 4 µM 25-hydroxycholeterol with various concentrations of Vitisin A or C3G for 24 h. It was found that Vitisin A decreased the cholesterol levels at the concentrations of 100 µM and 200 µM with a dose-response relationship, while C3G exhibited no significant effect on cellular cholesterol. Furthermore, Vitisin A could down-regulate 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (HMGCR) to inhibit cholesterol biosynthesis through a sterol regulatory element-binding protein 2 (SREBP2)-dependent mechanism, and up-regulate low-density lipoprotein receptor (LDLR) and blunt the secretion of proprotein convertase subtilisin/kexin type 9 (PCSK9) protein to promote intracellular LDL uptake without LDLR degradation. In conclusion, Vitisin A demonstrated hypocholesterolemic activity, by inhibiting cholesterol biosynthesis and enhancing LDL uptake in HepG2 cells.
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Antocianinas , Pró-Proteína Convertase 9 , Humanos , Pró-Proteína Convertase 9/genética , Células Hep G2 , Colesterol/metabolismo , Receptores de LDL/metabolismoRESUMO
Lorneic acid and related natural products are characterized by a trialkyl-substituted benzene ring. The formation of the aromatic core in the middle of the polyketide chain is unusual. We characterized a cytochromeâ P450 enzyme that can catalyze the hallmark benzene ring formation from an acyclic polyene substrate through genetic and biochemical analysis. Using this P450 as a beacon for genome mining, we obtained 12 homologous type I polyketide synthase (PKS) gene clusters, among which two gene clusters are activated and able to produce trialkyl-substituted aromatic polyketides. Quantum chemical calculations were performed to elucidate the plausible mechanism for P450-catalyzed benzene ring formation. Our work expands our knowledge of the catalytic diversity of cytochromeâ P450.
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Policetídeos , Policetídeos/química , Benzeno , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Sistema Enzimático do Citocromo P-450 , Metabolismo SecundárioRESUMO
OBJECTIVES: AcMNPV is a kind of microbial insecticide that can significantly relieve the resistance of Spodoptera frugiperda to chemical pesticides. TPP is a widely used synergist, which can reduce the use of pesticides by inhibiting carboxylesterase. It is emergently needed to develop a biological control way of Spodoptera frugiperda. RESULTS: GP64 mediates low-pH-triggered membrane fusion during entry by endocytosis and participates in AcMNPV particle budding. We explored the synergistic anti-insect activity of AcMNPV-gp64-EGFP and TPP. AcMNPV-gp64-EGFP could increase progeny virus proliferation and accelerate the transcription of 38k and vp39 genes. TPP could inhibit the carboxylesterase activity in the midgut of Spodoptera frugiperda larvae infected with AcMNPV-gp64-EGFP and enhance the virulence of AcMNPV-gp64-EGFP to Spodoptera frugiperda. CONCLUSIONS: TPP targeted carboxylesterase inhibition so that AcMNPV-gp64-EGFP could escape the antiviral response in insect hosts. It provided a novel strategy for the prevention of Spodoptera frugiperda.
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Praguicidas , Animais , Hidrolases de Éster Carboxílico , Proteínas de Fluorescência Verde/metabolismo , Nucleopoliedrovírus , Organofosfatos , Spodoptera , Proteínas do Envelope Viral/metabolismoRESUMO
Background: This study aimed to develop a nomogram to predict reduced cardiac function for acute kidney injury (AKI) patients who received continuous renal replacement therapy (CRRT) after acute type A aortic dissection (ATAAD) surgery. Methods: This study was a retrospective analysis. ATAAD patients with preoperative normal ejection fraction (EF) and postoperative AKI with CRRT admitted between January 2014 and November 2021 were included. The reduced cardiac function was defined as EF <50%. The data were analyzed by the univariate and multivariate logistic regression analyses. A diagnostic model was established by a nomogram, and its discriminative performance was validated by the received operating characteristic (ROC) curve and concordance (C) statistic. The calibration of the diagnostic model was tested by calibration curves and the HosmerLemeshow test. The clinical utility was evaluated by the decision curve analysis (DCA). Result: In total, 208 patients were eligible for analysis, of which 98 patients with reduced cardiac function. The logistic regression analyses showed age ≥60 years old, history of coronary atherosclerotic disease, preoperative pericardial tamponade, and cardiopulmonary bypass time were risk factors for reduced cardiac function, which were further employed in the nomogram. As results, nomogram revealed a high predictive power (C statistic = 0.723, 0.654-0.792; the bootstrap-corrected concordance C statistic = 0.711, the area under the ROC curve = 0.723). The calibration curves showed good consistency between the predicted and the actual probabilities (calibration curve: Brier points = 0.208, Emax = 0.103, Eavg = 0.021; Hosmer-Lemeshow test, P = 0.476). DCA showed that the nomogram could augment net benefits and exhibited a wide range of threshold probabilities in the prediction of EF reduction. Conclusion: This nomogram is an effective diagnostic model for predicting the reduced cardiac function in postoperative ATAAD patients with AKI undergoing CRRT and can be used to protect postoperative renal functions and facilitate patient-specific care after ATAAD surgery.
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Background: This study aimed to construct a model to predict the risk of in-hospital death in patients with acute renal injury (AKI) receiving continuous renal replacement therapy (CRRT) after acute type A aortic dissection (ATAAD) surgery. Methods: We reviewed the data of patients with AKI undergoing CRRT after ATAAD surgery. The patients were divided into survival and nonsurvival groups based on their vital status at hospital discharge. The data were analyzed using univariate and multivariate logistic regression analyses. Establish a risk prediction model using a nomogram and its discriminative ability was validated using C statistic and the receiver operating characteristic (ROC) curve. Its calibration ability was tested using a calibration curve, 10-fold cross-validation and Hosmer-Lemeshow test. Results: Among 175 patients, in-hospital death occurred in 61 (34.9%) patients. The following variables were incorporated in predicting in-hospital death: age > 65 years, lactic acid 12 h after CRRT, liver dysfunction, and permanent neurological dysfunction. The risk model revealed good discrimination (C statistic = 0.868, 95% CI: 0.806-0.930; a bootstrap-corrected C statistic of 0.859, the area under the ROC = 0.868). The calibration curve showed good consistency between predicted and actual probabilities (via 1,000 bootstrap samples, mean absolute error = 2.2%; Hosmer-Lemeshow test, P = 0.846). The 10-fold cross validation of the nomogram showed that the average misdiagnosis rate was 16.64%. Conclusion: The proposed model could be used to predict the probability of in-hospital death in patients undergoing CRRT for AKI after ATAAD surgery. It had the potential to assist doctors to identify the gravity of the situation and make the targeted therapeutic measures.
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Cinnamoyl-containing natural products (CCNPs) are a small class of bacterial metabolites with notable bioactivities. The biosynthesis of cinnamoyl moiety has been proposed to be assembled by an unusual highly reducing (HR) type II polyketide synthases (PKS). However, the biosynthetic route, especially the cyclization step for the benzene ring formation, remains unclear. In this work, we successfully reconstituted the pathway of cinnamoyl moiety in kitacinnamycin biosynthesis through a step-wise approach in vitro and demonstrated that a three-protein complex, Kcn17-Kcn18-Kcn19, can catalyze 6π-electrocyclization followed by dehydrogenation to form the benzene ring. We found that the three-protein homologues were widely distributed among 207 HR type II PKS biosynthetic gene clusters including five known CCNPs. In contrast, in the biosynthesis of youssoufene, a cinnamoyl-containing polyene, we identified that the benzene ring formation was accomplished by a distinct orphan protein. Thus, our work resolved the long-standing mystery in cinnamoyl biosynthesis and revealed two distinct enzymes that can synthesize benzene rings via polyene precursors.