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1.
Nature ; 559(7714): 419-422, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29995849

RESUMO

The spliceosome catalyses the excision of introns from pre-mRNA in two steps, branching and exon ligation, and is assembled from five small nuclear ribonucleoprotein particles (snRNPs; U1, U2, U4, U5, U6) and numerous non-snRNP factors1. For branching, the intron 5' splice site and the branch point sequence are selected and brought by the U1 and U2 snRNPs into the prespliceosome1, which is a focal point for regulation by alternative splicing factors2. The U4/U6.U5 tri-snRNP subsequently joins the prespliceosome to form the complete pre-catalytic spliceosome. Recent studies have revealed the structural basis of the branching and exon-ligation reactions3, however, the structural basis of the early events in spliceosome assembly remains poorly understood4. Here we report the cryo-electron microscopy structure of the yeast Saccharomyces cerevisiae prespliceosome at near-atomic resolution. The structure reveals an induced stabilization of the 5' splice site in the U1 snRNP, and provides structural insights into the functions of the human alternative splicing factors LUC7-like (yeast Luc7) and TIA-1 (yeast Nam8), both of which have been linked to human disease5,6. In the prespliceosome, the U1 snRNP associates with the U2 snRNP through a stable contact with the U2 3' domain and a transient yeast-specific contact with the U2 SF3b-containing 5' region, leaving its tri-snRNP-binding interface fully exposed. The results suggest mechanisms for 5' splice site transfer to the U6 ACAGAGA region within the assembled spliceosome and for its subsequent conversion to the activation-competent B-complex spliceosome7,8. Taken together, the data provide a working model to investigate the early steps of spliceosome assembly.


Assuntos
Microscopia Crioeletrônica , Saccharomyces cerevisiae/ultraestrutura , Spliceossomos/metabolismo , Spliceossomos/ultraestrutura , Processamento Alternativo/genética , Modelos Moleculares , Sítios de Splice de RNA , Fatores de Processamento de RNA/metabolismo , Ribonucleoproteína Nuclear Pequena U1/química , Ribonucleoproteína Nuclear Pequena U1/metabolismo , Ribonucleoproteína Nuclear Pequena U1/ultraestrutura , Ribonucleoproteína Nuclear Pequena U2/química , Ribonucleoproteína Nuclear Pequena U2/metabolismo , Ribonucleoproteína Nuclear Pequena U4-U6/química , Ribonucleoproteína Nuclear Pequena U4-U6/metabolismo , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Spliceossomos/química
2.
Anal Chem ; 95(41): 15217-15226, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37800729

RESUMO

Dengue is a viral disease transmitted by Aedes aegypti mosquitoes. According to the World Health Organization, about half of the world's population is at risk of dengue. There are four serotypes of the dengue virus. After infection with one serotype, it will be immune to such a serotype. However, subsequent infection with other serotypes will increase the risk of severe outcomes, e.g., dengue hemorrhagic fever, dengue shock syndrome, and even death. Since severe dengue is challenging to predict and lacks molecular markers, we aim to build a multiplexed Flavivirus protein microarray (Flaviarray) that includes all of the common Flaviviruses to profile the humoral immunity and cross-reactivity in the dengue patients with different outcomes. The Flaviarrays we fabricated contained 17 Flavivirus antigens with high reproducibility (R-square = 0.96) and low detection limits (172-214 pg). We collected serums from healthy subjects (n = 36) and dengue patients within 7 days after symptom onset (mild dengue (n = 21), hospitalized nonsevere dengue (n = 29), and severe dengue (n = 36)). After profiling the serum antibodies using Flaviarrays, we found that patients with severe dengue showed higher IgG levels against multiple Flavivirus antigens. With logistic regression, we found groups of markers with high performance in distinguishing dengue patients from healthy controls as well as hospitalized from mild cases (AUC > 0.9). We further reported some single markers that were suitable to separate dengue patients from healthy controls (AUC > 0.9) and hospitalized from mild outcomes (AUC > 0.8). Together, Flaviarray is a valuable tool to profile antibody specificities, uncover novel markers for decision-making, and shed some light on early preventions and treatments.


Assuntos
Vírus da Dengue , Dengue , Flavivirus , Dengue Grave , Animais , Humanos , Dengue/diagnóstico , Anticorpos Antivirais , Análise Serial de Proteínas , Reprodutibilidade dos Testes , Antígenos Virais
3.
Analyst ; 148(19): 4698-4709, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37610260

RESUMO

Kawasaki disease (KD) is a form of acute systemic vasculitis syndrome that predominantly occurs in children under the age of 5 years. Its etiology has been postulated due to not only genetic factors but also the presence of foreign antigens or infectious agents. To evaluate possible associations between Kawasaki disease (KD) and COVID-19, we investigated humoral responses of KD patients against S-protein variants with SARS-CoV-2 variant protein microarrays. In this study, plasma from a cohort of KD (N = 90) and non-KD control (non-KD) (N = 69) subjects in categories of unvaccinated-uninfected (pre-pandemic), SARS-CoV-2 infected (10-100 days after infection), and 1-dose, 2-dose, and 3-dose BNT162b2 vaccinated (10-100 days after vaccination) was collected. The principal outcomes were non-KD-KD differences for each category in terms of anti-human/anti-His for binding antibodies and neutralizing percentage for surrogate neutralizing antibodies. Binding antibodies against spikes were lower in the KD subjects with 1-dose of BNT162b2, and mean differences were significant for the P.1 S-protein (non-KD-KD, 3401; 95% CI, 289.0 to 6512; P = 0.0252), B.1.617.2 S-protein (non-KD-KD, 4652; 95% CI, 215.8 to 9087; P = 0.0351) and B.1.617.3 S-protein (non-KD-KD, 4874; 95% CI, 31.41 to 9716; P = 0.0477). Neutralizing antibodies against spikes were higher in the KD subjects with 1-dose of BNT162b2, and mean percentage differences were significant for the 1-dose BNT162b2 B.1.617.3 S-protein (non-KD-KD, -22.89%; 95% CI, -45.08 to -0.6965; P = 0.0399), B.1.1.529 S-protein (non-KD-KD, -25.96%; 95% CI, -50.53 to -1.376; P = 0.0333), BA.2.12.1 S-protein (non-KD-KD, -27.83%; 95% CI, -52.55 to -3.115; P = 0.0195), BA.4 S-protein (non-KD-KD, -28.47%; 95% CI, -53.59 to -3.342; P = 0.0184), and BA.5 S-protein (non-KD-KD, -30.42%; 95% CI, -54.98 to -5.869; P = 0.0077). In conclusion, we have found that KD patients have a comparable immunization response to healthy individuals to SARS-CoV-2 infection and COVID-19 immunization.


Assuntos
COVID-19 , Síndrome de Linfonodos Mucocutâneos , Criança , Humanos , Pré-Escolar , SARS-CoV-2/genética , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/genética , Vacina BNT162 , Análise Serial de Proteínas , Vacinação , Imunização , Anticorpos Neutralizantes , Anticorpos Antivirais
4.
Nature ; 546(7660): 617-621, 2017 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-28530653

RESUMO

Intron removal requires assembly of the spliceosome on precursor mRNA (pre-mRNA) and extensive remodelling to form the spliceosome's catalytic centre. Here we report the cryo-electron microscopy structure of the yeast Saccharomyces cerevisiae pre-catalytic B complex spliceosome at near-atomic resolution. The mobile U2 small nuclear ribonucleoprotein particle (snRNP) associates with U4/U6.U5 tri-snRNP through the U2/U6 helix II and an interface between U4/U6 di-snRNP and the U2 snRNP SF3b-containing domain, which also transiently contacts the helicase Brr2. The 3' region of the U2 snRNP is flexibly attached to the SF3b-containing domain and protrudes over the concave surface of tri-snRNP, where the U1 snRNP may reside before its release from the pre-mRNA 5' splice site. The U6 ACAGAGA sequence forms a hairpin that weakly tethers the 5' splice site. The B complex proteins Prp38, Snu23 and Spp381 bind the Prp8 N-terminal domain and stabilize U6 ACAGAGA stem-pre-mRNA and Brr2-U4 small nuclear RNA interactions. These results provide important insights into the events leading to active site formation.


Assuntos
Microscopia Crioeletrônica , Saccharomyces cerevisiae , Spliceossomos/química , Spliceossomos/ultraestrutura , Sequência de Bases , Biocatálise , Domínio Catalítico , Íntrons/genética , Modelos Biológicos , Modelos Moleculares , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Ligação Proteica , Domínios Proteicos , Estabilidade Proteica , RNA Helicases/química , RNA Helicases/metabolismo , RNA Helicases/ultraestrutura , Precursores de RNA/genética , Precursores de RNA/metabolismo , Precursores de RNA/ultraestrutura , Sítios de Splice de RNA/genética , Splicing de RNA , Fatores de Processamento de RNA/química , Fatores de Processamento de RNA/metabolismo , RNA Nuclear Pequeno/química , RNA Nuclear Pequeno/metabolismo , Ribonucleoproteína Nuclear Pequena U2/química , Ribonucleoproteína Nuclear Pequena U2/metabolismo , Ribonucleoproteína Nuclear Pequena U4-U6/química , Ribonucleoproteína Nuclear Pequena U4-U6/metabolismo , Ribonucleoproteína Nuclear Pequena U5/química , Ribonucleoproteína Nuclear Pequena U5/metabolismo , Ribonucleoproteínas Nucleares Pequenas/química , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/ultraestrutura , Spliceossomos/metabolismo
5.
Ecotoxicol Environ Saf ; 249: 114375, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36508836

RESUMO

Microplastics (MPs) are widespread in the environment and can be ingested through food, water, and air, posing a threat to human health. In addition, MPs can have a potential combined effect with other toxic compounds. Polystyrene (PS) has been shown to enhance the cytotoxicity of okadaic acid (OA). However, it remains unclear whether this enhancement effect is related to the size of PS particles. In this study, we investigated the mechanism of the combined effect of PS microplastics (PS-MPs) or PS nanoplastics (PS-NPs) and OA on Caco-2 cells. The results indicated that PS-NPs enhanced the cytotoxicity of OA and induced endoplasmic reticulum (ER) stress-mediated apoptosis in Caco-2 cells, compared to PS-MPs. Specifically, PS-NPs and OA cause more severe oxidative stress, lactate dehydrogenase (LDH) release, and mitochondrial membrane depolarization. Furthermore, it induced intracellular calcium overload through store-operated channels (SOCs) and activated the PERK/ATF-4/CHOP pathway to cause ER stress. ER stress promoted mitochondrial damage and finally activated the caspase family to induce apoptosis. This study provided an indirect basis for the assessment of the combined toxicity of MPs or NPs with OA.


Assuntos
Apoptose , Microplásticos , Ácido Okadáico , Poliestirenos , Poluentes Químicos da Água , Humanos , Apoptose/efeitos dos fármacos , Células CACO-2 , Microplásticos/toxicidade , Ácido Okadáico/toxicidade , Plásticos , Poliestirenos/toxicidade , Poluentes Químicos da Água/toxicidade
6.
Int J Mol Sci ; 24(10)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37240438

RESUMO

Human noroviruses (HuNoV) are major causes of acute gastroenteritis around the world. The high mutation rate and recombination potential of noroviruses are significant challenges in studying the genetic diversity and evolution pattern of novel strains. In this review, we describe recent advances in the development of technologies for not only the detection but also the analysis of complete genome sequences of noroviruses and the future prospects of detection methods for tracing the evolution and genetic diversity of human noroviruses. The mechanisms of HuNoV infection and the development of antiviral drugs have been hampered by failure to develop the infectious virus in a cell model. However, recent studies have demonstrated the potential of reverse genetics for the recovery and generation of infectious viral particles, suggesting the utility of this genetics-based system as an alternative for studying the mechanisms of viral infection, such as cell entry and replication.


Assuntos
Infecções por Caliciviridae , Norovirus , Humanos , Norovirus/genética , Antivirais/farmacologia , Antivirais/uso terapêutico , Infecções por Caliciviridae/genética
7.
Biochem Biophys Res Commun ; 634: 10-19, 2022 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-36228540

RESUMO

Extracellular vesicles (EVs) and their exosome subsets are vesicle-like nanoparticles (EVs) that are secreted by cells and contain various factors that treat various diseases. However, studies on extracting EVs from marine shellfish are still relatively lacking. In this study, EVs were isolated from Pinctada martensii mucus and the efficacy of EVs in modulating the inflammatory environment was demonstrated. A human skin inflammatory cell model was established to investigate the effect of Pinctada martensii mucus-derived EVs on inflammation. The results showed that EVs could restore the viability of inflammatory HaCaT cells and decrease the level of reactive oxygen species (ROS), as well as the mRNA expression of IL-6, IL-8 and TNF-α. The inflammation of HaCaT cells was treated by inhibiting the activation of the MAPK, NF-κB and NLRP3 inflammasome signaling pathways, which prevented the phosphorylation of related inflammatory proteins and the entry of P65 protein into the nucleus. This study provides novel EVs from marine shellfish-derived bioactive materials.


Assuntos
Dermatite , Vesículas Extracelulares , Pinctada , Animais , Humanos , Vesículas Extracelulares/metabolismo , Inflamassomos/metabolismo , Inflamação , Muco/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pinctada/metabolismo , Proteínas Quinases Ativadas por Mitógeno
8.
J Biomed Sci ; 29(1): 102, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36457101

RESUMO

BACKGROUND: yqiC is required for colonizing the Salmonella enterica serovar Typhimurium (S. Typhimurium) in human cells; however, how yqiC regulates nontyphoidal Salmonella (NTS) genes to influence bacteria-host interactions remains unclear. METHODS: The global transcriptomes of S. Typhimurium yqiC-deleted mutant (ΔyqiC) and its wild-type strain SL1344 after 2 h of in vitro infection with Caco-2 cells were obtained through RNA sequencing to conduct comparisons and identify major yqiC-regulated genes, particularly those involved in Salmonella pathogenicity islands (SPIs), ubiquinone and menaquinone biosynthesis, electron transportation chains (ETCs), and carbohydrate/energy metabolism. A Seahorse XFp Analyzer and assays of NADH/NAD+ and H2O2 were used to compare oxygen consumption and extracellular acidification, glycolysis parameters, adenosine triphosphate (ATP) generation, NADH/NAD+ ratios, and H2O2 production between ΔyqiC and SL1344. RESULTS: After S. Typhimurium interacts with Caco-2 cells, yqiC represses gene upregulation in aspartate carbamoyl transferase, type 1 fimbriae, and iron-sulfur assembly, and it is required for expressing ilvB operon, flagellin, tdcABCD, and dmsAB. Furthermore, yqiC is required for expressing mainly SPI-1 genes and specific SPI-4, SPI-5, and SPI-6 genes; however, it diversely regulates SPI-2 and SPI-3 gene expression. yqiC significantly contributes to menD expression in menaquinone biosynthesis. A Kyoto Encyclopedia of Genes and Genomes analysis revealed the extensive association of yqiC with carbohydrate and energy metabolism. yqiC contributes to ATP generation, and the analyzer results demonstrate that yqiC is required for maintaining cellular respiration and metabolic potential under energy stress and for achieving glycolysis, glycolytic capacity, and glycolytic reserve. yqiC is also required for expressing ndh, cydA, nuoE, and sdhB but suppresses cyoC upregulation in the ETC of aerobically and anaerobically grown S. Typhimurium; priming with Caco-2 cells caused a reversed regulation of yiqC toward upregulation in these ETC complex genes. Furthermore, yqiC is required for maintaining NADH/NAD+ redox status and H2O2 production. CONCLUSIONS: Specific unreported genes that were considerably regulated by the colonization-associated gene yqiC in NTS were identified, and the key role and tentative mechanisms of yqiC in the extensive modulation of virulence factors, SPIs, ubiquinone and menaquinone biosynthesis, ETCs, glycolysis, and oxidative stress were discovered.


Assuntos
Salmonella typhimurium , Transcriptoma , Humanos , Salmonella typhimurium/genética , NAD , Ubiquinona , Células CACO-2 , Peróxido de Hidrogênio/farmacologia , Vitamina K 2 , Respiração Celular , Estresse Oxidativo/genética , Trifosfato de Adenosina , Carboidratos
9.
Mar Drugs ; 20(5)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35621950

RESUMO

Sargassum fucoidan is a kind of sulfated heteropolysaccharide with a variety of biological activities. The aim of this study was to investigate the extraction, purification, physicochemical characterization and in vitro antithrombotic activity of fucoidan from Sargassum henslowianum C.Agardh. Hot-water-assisted ultrasound was used to extract fucoidan (F). Fucoidan was purified by DEAE cellulose 52 (F1), Vc-H2O2 (FD1) and Superdex 75 gel (FDS1). The physical and chemical properties of fucoidans were analyzed by chemical composition, monosaccharide composition, average molecular weight (Mw) and FTIR. The sulfate contents of F, F1, FD1 and FDS1 were 11.45%, 16.35% and 17.52%, 9.66%, respectively; the Mw was 5.677 × 105, 4.393 × 105, 2.176 × 104 and 6.166 × 103, respectively. The results of monosaccharide composition showed that the four fucoidans contained l-fucose, d-galactose, l-mannose, d-xylose, l-rhamnose and d-glucose, but the mass fraction ratio was different. The results of FTIR showed that fucoidan contained characteristic peaks of sugar and sulfate. In vitro, F1, FD1 and FDS1 could alleviate HUVEC damage induced by adrenaline (Adr). F1, FD1 and FDS1 decreased vWF and TF and increased the ratio of t-PA/PAI-1 in Adr-induced HUVEC.


Assuntos
Sargassum , Fibrinolíticos/farmacologia , Peróxido de Hidrogênio , Monossacarídeos , Polissacarídeos , Sargassum/química , Sulfatos
10.
Sensors (Basel) ; 22(14)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35890872

RESUMO

Nowadays, the grinding process is mostly automatic, yet post-grinding quality inspection is mostly carried out manually. Although the conventional inspection technique may have cumbersome setup and tuning processes, the data-driven model, with its vision-based dataset, provides an opportunity to automate the inspection process. In this study, a convolutional neural network technique with transfer learning is proposed for three kinds of inspections based on 750-1000 surface raw images of the ground workpieces in each task: classifying the grit number of the abrasive belt that grinds the workpiece, estimating the surface roughness of the ground workpiece, and classifying the degree of wear of the abrasive belts. The results show that a deep convolutional neural network can recognize the texture on the abrasive surface images and that the classification model can achieve an accuracy of 0.9 or higher. In addition, the external coaxial white light was the most suitable light source among the three tested light sources: the external coaxial white light, the high-angle ring light, and the external coaxial red light. Finally, the model that classifies the degree of wear of the abrasive belts can also be utilized as the abrasive belt life estimator.

11.
Ecotoxicol Environ Saf ; 227: 112885, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34634601

RESUMO

The coexistence of nanoplastics (NPs) and pollutants such as arsenic (As) has become an unignorable environmental problem. However, there is still a considerable knowledge gap about the impact of NPs and pollutants on human health risks. In this study, the human gastric adenocarcinoma (AGS) cells were used as a model to investigate the toxicity of NPs with different particle sizes and As by MTT assay, western blotting, immunofluorescence and so on. The results showed that 20 nm (8 µg/mL), 50 nm (128 µg/mL), 200 nm (128 µg/mL), 500 nm (128 µg/mL), 1000 nm (128 µg/mL) polystyrene (PS) did not affect cell viability, ROS, intracellular calcium and activate apoptosis pathway in AGS cells. However, noncytotoxic concentration of NPs enhanced the cytotoxicity and intracellular accumulation of As. NPs destroys the fluidity of cell membrane and cytoskeleton, inhibits the activity of ABC transporter, and leads to the accumulation of As in cells. This work highlights that the damage caused by NPs, especially at the level of noncytotoxicity, joint with As cannot be ignored and provides a specific toxicological mechanism of NPs accompanied by exposure to As.


Assuntos
Arsênio , Nanopartículas , Transportadores de Cassetes de Ligação de ATP , Citoesqueleto , Humanos , Microplásticos
12.
Nucleic Acids Res ; 46(7): 3764-3773, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29390077

RESUMO

Cwc23 is a member of the J protein family, and has been shown to interact with Ntr1, a scaffold protein that interacts with Ntr2 and Prp43 to form the NTR complex that mediates spliceosome disassembly. We show that Cwc23 is also an intrinsic component of the NTR complex, and that it interacts with the carboxyl terminus of Ntr1. Metabolic depletion of Cwc23 concurrently depleted Ntr1 and Ntr2, suggesting a role for Cwc23 in stabilizing these two proteins. Ntr1, Ntr2 and Cwc23 are stoichiometrically balanced, and form a stable heterotrimer. Depletion of Cwc23 from splicing extracts using antibodies resulted in depletion of all three proteins and accumulation of intron-lariat in the splicing reaction. Cwc23 is not required for disassembly of intron-lariat spliceosome (ILS), but facilitates disassembly of spliceosome intermediates after the actions of Prp2 and Prp16 by stabilizing the association of Ntr1 with the spliceosome. Cwc23 has a more limited effect on the association of Ntr1 with the ILS. Our data suggest that Cwc23 is important for maintaining the levels of Ntr1 and Ntr2, and that it also plays a regulatory role in targeting spliceosome intermediates for disassembly.


Assuntos
Chaperonas Moleculares/genética , Proteínas de Saccharomyces cerevisiae/genética , Spliceossomos/genética , Adenosina Trifosfatases/genética , RNA Helicases DEAD-box/genética , Íntrons/genética , Chaperonas Moleculares/antagonistas & inibidores , Ligação Proteica , RNA Helicases/genética , Splicing de RNA/genética , Fatores de Processamento de RNA/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores
13.
Chin J Physiol ; 63(4): 149-155, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32859881

RESUMO

Resveratrol (RSV) has been demonstrated to ameliorate nonalcoholic fatty liver disease (NAFLD) in animal studies. However, RSV was given with the dosage that ranged from 7 to 300 mg/kg body weight (BW). Hence, the study aimed to investigate the efficacy of RSV at a lower dosage on high cholesterol-fructose diet (HCFD)-induced rat model of NAFLD. In the study, male Sprague-Dawley rats were fed with HCFD for 15 weeks. RSV was also given at a daily dose of 1 mg/kg BW for 15 days or 15 weeks by oral delivery. At sacrifice, plasma and liver specimens were acquired for detections of alanine and aspartate aminotransferases, proinflammatory cytokines, and lipid contents. Histological examinations and Western blotting analysis were performed using liver tissues. The results showed that RSV administration reduced plasma levels of aminotransferases and proinflammatory cytokines including interleukin-1 beta (IL-1ß), IL-6, and tumor necrosis factor-alpha (TNF-α) in HCFD-induced NAFLD. RSV also mitigated hepatic lipid accumulation and expression of IL-1ß, IL-6, and TNF-α. Besides, phosphorylation of signal transducer and activator of transcription 3 (STAT3) was reduced with RSV supplementation in the liver of HCFD-fed rats. We concluded that low-dose RSV supplementation attenuated hepatic inflammation and lipid accumulation in HCFD-induced NAFLD. The ameliorative effect of RSV on NAFLD could be associated with downregulation of phosphorylated STAT3.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica , Frutose , Inflamação , Lipídeos , Fígado , Masculino , Ratos , Ratos Sprague-Dawley , Resveratrol
14.
Tour Manag ; 81: 104161, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32536740

RESUMO

Carbon mitigation strategies are an urgent and overdue tourism industry imperative. The tourism response to climate action has been to engage businesses in technology adoption, and to encourage more sustainable visitor behaviour. These strategies however are insufficient to mitigate the soaring carbon footprint of tourism. Building upon the concepts of optimization and eco-efficiency, we put forward a novel carbon mitigation approach, which seeks to pro-actively determine, foster, and develop a long-term tourist market portfolio. This can be achieved through intervening and reconfiguring the demand mix with the fundamental aim of promoting low carbon travel markets. The concept and the analytical framework that quantitatively inform optimization of the desired market mix are presented. Combining the "de-growth" and "optimization" strategies, it is demonstrated that in the case study of Taiwan, great potential exists to reduce emissions and sustain economic yields. The implications for tourism destination managers and wider industry stakeholders are discussed.

15.
EMBO J ; 31(6): 1579-90, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22314233

RESUMO

SF3a is an evolutionarily conserved heterotrimeric complex essential for pre-mRNA splicing. It functions in spliceosome assembly within the mature U2 snRNP (small nuclear ribonucleoprotein particle), and its displacement from the spliceosome initiates the first step of the splicing reaction. We have identified a core domain of the yeast SF3a complex required for complex assembly and determined its crystal structure. The structure shows a bifurcated assembly of three subunits, Prp9, Prp11 and Prp21, with Prp9 interacting with Prp21 via a bidentate-binding mode, and Prp21 wrapping around Prp11. Structure-guided biochemical analysis also shows that Prp9 harbours a major binding site for stem-loop IIa of U2 snRNA. These findings provide mechanistic insights into the assembly of U2 snRNP.


Assuntos
Ribonucleoproteína Nuclear Pequena U2/química , Proteínas de Saccharomyces cerevisiae/química , Sítios de Ligação , Modelos Moleculares , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Subunidades Proteicas , Splicing de RNA , Fatores de Processamento de RNA , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteína Nuclear Pequena U2/genética , Ribonucleoproteína Nuclear Pequena U2/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
16.
Sensors (Basel) ; 15(3): 4925-46, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25734644

RESUMO

We report on a sensor data fusion algorithm via an extended Kalman filter for estimating the spatial motion of a bipedal robot. Through fusing the sensory information from joint encoders, a 6-axis inertial measurement unit and a 2-axis inclinometer, the robot's body state at a specific fixed position can be yielded. This position is also equal to the CoM when the robot is in the standing posture suggested by the detailed CAD model of the robot. In addition, this body state is further utilized to provide sensory information for feedback control on a bipedal robot with walking gait. The overall control strategy includes the proposed body state estimator as well as the damping controller, which regulates the body position state of the robot in real-time based on instant and historical position tracking errors. Moreover, a posture corrector for reducing unwanted torque during motion is addressed. The body state estimator and the feedback control structure are implemented in a child-size bipedal robot and the performance is experimentally evaluated.

17.
Genome Res ; 21(1): 56-67, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21036922

RESUMO

Half of prostate cancers harbor gene fusions between TMPRSS2 and members of the ETS transcription factor family. To date, little is known about the presence of non-ETS fusion events in prostate cancer. We used next-generation transcriptome sequencing (RNA-seq) in order to explore the whole transcriptome of 25 human prostate cancer samples for the presence of chimeric fusion transcripts. We generated more than 1 billion sequence reads and used a novel computational approach (FusionSeq) in order to identify novel gene fusion candidates with high confidence. In total, we discovered and characterized seven new cancer-specific gene fusions, two involving the ETS genes ETV1 and ERG, and four involving non-ETS genes such as CDKN1A (p21), CD9, and IKBKB (IKK-beta), genes known to exhibit key biological roles in cellular homeostasis or assumed to be critical in tumorigenesis of other tumor entities, as well as the oncogene PIGU and the tumor suppressor gene RSRC2. The novel gene fusions are found to be of low frequency, but, interestingly, the non-ETS fusions were all present in prostate cancer harboring the TMPRSS2-ERG gene fusion. Future work will focus on determining if the ETS rearrangements in prostate cancer are associated or directly predispose to a rearrangement-prone phenotype.


Assuntos
Fusão Gênica , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas c-ets/genética , Análise de Sequência de RNA/métodos , Antígenos CD/genética , Biologia Computacional/métodos , Inibidor de Quinase Dependente de Ciclina p21/genética , Perfilação da Expressão Gênica , Humanos , Quinase I-kappa B/genética , Hibridização in Situ Fluorescente , Masculino , Glicoproteínas de Membrana/genética , Dados de Sequência Molecular , Neoplasias da Próstata/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Tetraspanina 29 , Transativadores/metabolismo , Regulador Transcricional ERG
18.
J Appl Meas ; 15(2): 200-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24950537

RESUMO

This study assessed the ability of military aircrews to adapt to stressors when undergoing centrifuge training and determined what equipment items caused perceived stress and needed to be upgraded. We used questionnaires and the Rasch model to measure aircrew personnel's ability to adapt to centrifuge training. The measurement items were ranked by 611 military aircrew personnel. Analytical results indicated that the majority of the stress perceived by aircrew personnel resulted from the lightproof cockpit without outer reference. This study prioritized the equipment requiring updating as the lightproof cockpit design, the dim lighting of the cockpit, and the pedal design. A significant difference was found between pilot and non-pilot subjects' stress from the pedal design; and considerable association was discernible between the seat angle design and flight hours accrued. The study results provide aviators, astronauts, and air forces with reliable information as to which equipment items need to be urgently upgraded as their present physiological and psychological effects can affect the effectiveness of centrifuge training.


Assuntos
Medicina Aeroespacial/estatística & dados numéricos , Aeronaves , Centrifugação/psicologia , Gravidade Alterada , Militares/educação , Militares/psicologia , Psicometria/estatística & dados numéricos , Estresse Psicológico/complicações , Inquéritos e Questionários , Adaptação Psicológica , Aptidão , Humanos , Modelos Estatísticos , Reprodutibilidade dos Testes
19.
Bioinspir Biomim ; 19(2)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38346329

RESUMO

This paper proposes a generalized spring-loaded inverted pendulum (G-SLIP) model to explore various popular reduced-order dynamic models' characteristics and suggest a better robot leg design under specified performance indices. The G-SLIP model's composition can be varied by changing the model's parameters, such as ground contacting type and spring property. It can be transformed into four widely used models: the spring-loaded inverted pendulum (SLIP) model, the two-segment leg model, the SLIP with rolling foot model, and the rolling SLIP model. The effects of rolling contact and spring configuration on the dynamic behavior and fixed-point distribution of the G-SLIP model were analyzed, and the basins of attraction of the four described models were studied. By varying the parameters of the G-SLIP model, the dynamic behavior of the model can be optimized. Optimized for general locomotion running at various speeds, the model provided leg design guidelines. The leg was empirically fabricated and installed on the hexapod for experimental evaluation. The results indicated that the robot with a designed leg runs faster and is more power-efficient.


Assuntos
Robótica , Animais , Robótica/métodos , Modelos Biológicos , Locomoção , , Insetos , Fenômenos Biomecânicos , Perna (Membro) , Marcha
20.
Cell Death Dis ; 15(1): 24, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195677

RESUMO

ATP and its receptor P2RX7 exert a pivotal effect on antitumor immunity during chemotherapy-induced immunogenic cell death (ICD). Here, we demonstrated that TNFα-mediated PANX1 cleavage was essential for ATP release in response to chemotherapy in colorectal cancer (CRC). TNFα promoted PANX1 cleavage via a caspase 8/3-dependent pathway to enhance cancer cell immunogenicity, leading to dendritic cell maturation and T-cell activation. Blockade of the ATP receptor P2RX7 by the systemic administration of small molecules significantly attenuated the therapeutic efficacy of chemotherapy and decreased the infiltration of immune cells. In contrast, administration of an ATP mimic markedly increased the therapeutic efficacy of chemotherapy and enhanced the infiltration of immune cells in vivo. High PANX1 expression was positively correlated with the recruitment of DCs and T cells within the tumor microenvironment and was associated with favorable survival outcomes in CRC patients who received adjuvant chemotherapy. Furthermore, a loss-of-function P2RX7 mutation was associated with reduced infiltration of CD8+ immune cells and poor survival outcomes in patients. Taken together, these results reveal that TNFα-mediated PANX1 cleavage promotes ATP-P2RX7 signaling and is a key determinant of chemotherapy-induced antitumor immunity.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Humanos , Fator de Necrose Tumoral alfa , Ativação Linfocitária , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Trifosfato de Adenosina , Microambiente Tumoral , Proteínas do Tecido Nervoso , Conexinas/genética , Receptores Purinérgicos P2X7/genética
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