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N6-methyladenosine (m6 A) is an abundant nucleotide modification in mRNA, known to regulate mRNA stability, splicing, and translation, but it is unclear whether it is also has a physiological role in the intratumoral microenvironment and cancer drug resistance. Here, we find that METTL3, a primary m6 A methyltransferase, is significantly down-regulated in human sorafenib-resistant hepatocellular carcinoma (HCC). Depletion of METTL3 under hypoxia promotes sorafenib resistance and expression of angiogenesis genes in cultured HCC cells and activates autophagy-associated pathways. Mechanistically, we have identified FOXO3 as a key downstream target of METTL3, with m6 A modification of the FOXO3 mRNA 3'-untranslated region increasing its stability through a YTHDF1-dependent mechanism. Analysis of clinical samples furthermore showed that METTL3 and FOXO3 levels are tightly correlated in HCC patients. In mouse xenograft models, METTL3 depletion significantly enhances sorafenib resistance of HCC by abolishing the identified METTL3-mediated FOXO3 mRNA stabilization, and overexpression of FOXO3 restores m6 A-dependent sorafenib sensitivity. Collectively, our work reveals a critical function for METTL3-mediated m6 A modification in the hypoxic tumor microenvironment and identifies FOXO3 as an important target of m6 A modification in the resistance of HCC to sorafenib therapy.
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Adenosina/análogos & derivados , Autofagia/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteína Forkhead Box O3/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Sorafenibe/farmacologia , Adenosina/genética , Adenosina/metabolismo , Animais , Autofagia/genética , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proteína Forkhead Box O3/genética , Células HEK293 , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Metilação/efeitos dos fármacos , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/genética , RNA Mensageiro/genética , RNA Neoplásico/genéticaRESUMO
Surfactin is a cyclic hexalipopeptide compound, nonribosomal synthesized by representatives of the Bacillus subtilis species complex which includes B. subtilis group and its closely related species, such as B. subtilis subsp subtilis, B. subtilis subsp spizizenii, B. subtilis subsp inaquosorum, B. atrophaeus, B. amyloliquefaciens, B. velezensis (Steinke mSystems 6: e00057, 2021) It functions as a biosurfactant and signaling molecule and has antibacterial, antiviral, antitumor, and plant disease resistance properties. The Bacillus lipopeptides play an important role in agriculture, oil recovery, cosmetics, food processing and pharmaceuticals, but the natural yield of surfactin synthesized by Bacillus is low. This paper reviews the regulatory pathways and mechanisms that affect surfactin synthesis and release, highlighting the regulatory genes involved in the transcription of the srfAA-AD operon. The several ways to enhance surfactin production, such as governing expression of the genes involved in synthesis and regulation of surfactin synthesis and transport, removal of competitive pathways, optimization of media, and fermentation conditions were commented. This review will provide a theoretical platform for the systematic genetic modification of high-yielding strains of surfactin.
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Bacillus , Bacillus/genética , Bacillus/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Óperon , Fermentação , Lipopeptídeos , Peptídeos CíclicosRESUMO
OBJECTIVES: This study investigates the application of 15 Quality Indicators (QIs) in clinical laboratories in Fujian Province, China, from 2018 to 2023. It identifies the main causes of laboratory errors and explores issues in the application of QIs, providing a reference for establishing provincial state-of-the-art and operational quality specifications (QSs). METHODS: All clinical laboratories in Fujian Province were organized to submit general information and original QIs data through the online External Quality Assessment (EQA) system of the National Clinical Laboratory Center (NCCL) for a survey of 15 QIs. Data from 2018 to 2023 were downloaded for statistical analysis, and the current QSs for the 15 QIs in Fujian Province were compared and analyzed with those published by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Working Group on Laboratory Errors and Patient Safety (WG-LEPS). RESULTS: QIs data from 542 clinical laboratories were collected. The survey on data sources showed that the number of laboratories recording QIs data using Laboratory Information Systems (LIS) increased annually, but the growth was modest and the proportion was less than 50â¯%. Among the laboratories using LIS to record QIs data, 133 continuously participated in this survey for six years, reporting different QIs. Over the six years, all reported QIs showed significant improvement or at least remained stable. The best median Sigma (σ) metrics were for the percentage of critical values notification and timely critical values notification, reaching 6σ, followed by the percentage of incorrect laboratory reports, with σ metrics ranging from 4.9σ to 5.1σ. In contrast, the percentage of tests covered by internal quality control (IQC) (1.5σ-1.7σ) and inter-laboratory comparison (0.1σ) remained consistently low. Compared to the QSs published by IFCC WG-LEPS, the QSs for the 15 QIs in Fujian Province in 2023 were stricter or roughly equivalent, except for the percentage of incorrect laboratory reports (Fujian Province: 0-0.221, IFCC WG-LEPS: 0-0.03). CONCLUSIONS: 1. The application of QIs has significantly improved the quality of testing in clinical laboratories in Fujian Province, but the percentage of tests covered by IQC and inter-laboratory comparison remain low; 2. Effective application of QIs requires the establishment of comprehensive LIS, unified calculation standards, and other supporting measures.
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The transplantation of bone marrow mesenchymal stem cells (MSCs) in stroke is hindered by the restricted rates of survival and differentiation. Ginsenoside compound K (CK), is reported to have a neuroprotective effect and regulate energy metabolism. We applied CK to investigate if CK could promote the survival of MSCs and differentiation into brain microvascular endothelial-like cells (BMECs), thereby alleviating stroke symptoms. Therefore, transwell and middle cerebral artery occlusion (MCAO) models were used to mimic oxygen and glucose deprivation (OGD) in vitro and in vivo, respectively. Our results demonstrated that CK had a good affinity for GLUT1, which increased the expression of GLUT1 and the production of ATP, facilitated the proliferation and migration of MSCs, and activated the HIF-1α/VEGF signaling pathway to promote MSC differentiation. Moreover, CK cooperated with MSCs to protect BMECs, promote angiogenesis and vascular density, enhance neuronal and astrocytic proliferation, thereby reducing infarct volume and consequently improving neurobehavioral outcomes. These results suggest that the synergistic effects of CK and MSCs could potentially be a promising strategy for stroke.
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Ginsenosídeos , Transportador de Glucose Tipo 1 , Subunidade alfa do Fator 1 Induzível por Hipóxia , Células-Tronco Mesenquimais , Acidente Vascular Cerebral , Fator A de Crescimento do Endotélio Vascular , Ginsenosídeos/farmacologia , Animais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Masculino , Diferenciação Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Proliferação de Células/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , AngiogêneseRESUMO
Postharvest diseases lead to substantial economic losses to the pear industry (Xu et al. 2021). In August 2022 and 2023, 'Housui' pears (Pyrus pyrifolia) with no visible wounds were harvested from Baoying county, Jiangsu Province, China and stored at 20°C with 85% relative humidity. Approximately 8% of pear fruits showed soft rot after 15 days of storage. The margin area of rot tissue was aseptically incubated on PDA medium at 25°C. Mycelial tips were transferred to new PDA after 24 h. Five fungal isolates were obtained after isolation and identification, including Alternaria sp., Botryosphaeria sp., Diaporthe sp., Fusarium sp. and Gilbertella sp. For each isolate, pathogenicity tests were confirmed three times by placing 10 µL of spore suspension (106 spores/mL) on three 'Housui' pear fruits superficially wounded with sterile toothpicks, and sterile distilled water served as controls. Lesions caused by Gilbertella sp. were distinctly observed after incubating at 20°C for 24h, and controls have no symptom. The lesions expanded to large brown spots with smelling of alcohol after 48 h, similar to natural disease symptom. The colony of Gilbertella sp. was initially white and rapidly turned gray, generating large amounts of black sporangia. -Sporangia were firstly white, then turn black, globose to dorsoventrally flattened, 70.22 to 131.58 × 75 to 135.17 µm, average 93.19 × 106.54 µm (n = 50), borne erect or nodding, breaking into two equal pieces. Sporangiophores were hyaline, 11.17 to 34.57 µm wide, average 19.67 µm (n = 50). Columellae were hyaline, pyriform or obovoid to cylindrical, with a distinct basal collar, 32.37 to 102.84 × 23.62 to 68.68 µm, average 60.06 × 40.07 µm (n = 50). Sporangiospores were single celled, mostly ellipsoid, 5.76 to 11.49 × 3.89 to 6.18 µm, average 8.68 × 5.08 µm (n = 100), attaching with 4-5 hyaline appendages at the ends. Chlamydospores were solitary or in short chain, cylindrical or oval. Zygospore was not observed. The isolate was morphologically identified as G. persicaria (Benny 1991). Molecular identification was performed by PCR amplification, sequencing and phylogenetic analysis of the internal transcribed spacer region of rDNA (ITS), partial 28S rDNA large subunit (LSU), and actin-1 (ACT-1) gene using primer pairs ITS1/ITS4, LR0R/LR5 and Gil_ACT_F/Gil_ACT_R (Zhang et al. 2020). The ITS (OP897009), LSU (OR794326), and ACT-1 (OR805109) sequences revealed 99.85%, 99.30% and 100% sequence identity to nucleotide sequences of G. persicaria from NCBI (ON875318, OP243274, and AJ287159). Phylogenetic analysis based on the maximum likelihood method grouped the isolate with other G. persicaria strains. Pathogenicity of the isolate was performed on wounded and non-wounded fruits. Wounded fruits severely rot after 48 h, and no non-wounded fruit rot after 5 days. Therefore, wound was required for the infection of G. persicaria. The pathogen was consistently re-isolated and purified from the inoculated pears, morphologically identified as G. persicaria, fulfilling Koch's postulates. Fruit rot caused by G. persicaria has been reported on peach, tomato, apricot, plum, apple, dragon fruit, papaya and eggplant, as well as Pyrus communis (Mehrotra 1964; Ginting et al. 1996; Cruz-Lachica et al. 2021). This is the first report of G. persicaria infection on 'Housui' pears in China. This disease is a potential threat to 'Housui' pear storage. The confirmation of this soft rot pathogen provides a foundation for pear postharvest disease prevention.
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Necrotrophic fungus Rhizoctonia solani Kühn (R. solani) causes serious diseases in many crops worldwide, including rice and maize sheath blight (ShB). Crop resistance to the fungus is a quantitative trait and resistance mechanism remains largely unknown, severely hindering the progress on developing resistant varieties. In this study, we found that resistant variety YSBR1 has apparently stronger ability to suppress the expansion of R. solani than susceptible Lemont in both field and growth chamber conditions. Comparison of transcriptomic profiles shows that the photosynthetic system including chlorophyll biosynthesis is highly suppressed by R. solani in Lemont but weakly in YSBR1. YSBR1 shows higher chlorophyll content than that of Lemont, and inducing chlorophyll degradation by dark treatment significantly reduces its resistance. Furthermore, three rice mutants and one maize mutant that carry impaired chlorophyll biosynthesis all display enhanced susceptibility to R. solani. Overexpression of OsNYC3, a chlorophyll degradation gene apparently induced expression by R. solani infection, significantly enhanced ShB susceptibility in a high-yield ShB-susceptible variety '9522'. However, silencing its transcription apparently improves ShB resistance without compromising agronomic traits or yield in field tests. Interestingly, altering chlorophyll content does not affect rice resistance to blight and blast diseases, caused by biotrophic and hemi-biotrophic pathogens, respectively. Our study reveals that chlorophyll plays an important role in ShB resistance and suppressing chlorophyll degradation induced by R. solani infection apparently improves rice ShB resistance. This discovery provides a novel target for developing resistant crop to necrotrophic fungus R. solani.
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Oryza , Clorofila , Oryza/genética , Oryza/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , RhizoctoniaRESUMO
BACKGROUND: Long non-coding RNAs (lncRNAs) are widely involved in the pathogenesis of cancers. However, biological roles of lncRNAs in occurrence and progression of colorectal cancer (CRC) remain unclear. The current study aimed to evaluate the expression pattern of lncRNAs and messenger RNAs (mRNAs). METHODS: RNA sequencing (RNA-Seq) in CRC tissues and adjacent normal tissues from 6 CRC patients was performed and functional lncRNA-mRNA co-expression network was constructed afterwards. Gene enrichment analysis was demonstrated using DAVID 6.8 tool. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to validate the expression pattern of differentially expressed lncRNAs. Pearson correlation analysis was applied to evaluate the relationships between selected lncRNAs and mRNAs. RESULTS: One thousand seven hundred and sixteenth differentially expressed mRNAs and 311 differentially expressed lncRNAs were screened out. Among these, 568 mRNAs were up-regulated while 1148 mRNAs down-regulated, similarly 125 lncRNAs were up-regulated and 186 lncRNAs down-regulated. In addition, 1448 lncRNA-mRNA co-expression pairs were screened out from 940,905 candidate lncRNA-mRNA pairs. Gene enrichment analysis revealed that these lncRNA-related mRNAs are associated with cell adhesion, collagen adhesion, cell differentiation, and mainly enriched in ECM-receptor interaction and PI3K-Akt signaling pathways. Finally, RT-qPCR results verified the expression pattern of lncRNAs, as well as the relationships between lncRNAs and mRNAs in 60 pairs of CRC tissues. CONCLUSIONS: In conclusion, these results of the RNA-seq and bioinformatic analysis strongly suggested that the dysregulation of lncRNA is involved in the complicated process of CRC development, and providing important insight regarding the lncRNAs involved in CRC.
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Neoplasias Colorretais , RNA Longo não Codificante , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de RNA , TranscriptomaRESUMO
Rhizoctonia solani is one of the important pathogenic fungi causing several serious crop diseases, such as maize and rice sheath blight. Current methods used to control the disease mainly depend on spraying fungicides because there is no immunity or high resistance available in crops. Spraying double-strand RNA (dsRNA) for induced-gene silencing (SIGS) is a new potentially sustainable and environmentally friendly tool to control plant diseases. Here, we found that fluorescein-labelled EGFP-dsRNA could be absorbed by R. solani in co-incubation. Furthermore, three dsRNAs, each targeting one of pathogenicity-related genes, RsPG1, RsCATA, and RsCRZ1, significantly downregulated the transcript levels of the target genes after co-incubation, leading to a significant reduction in the pathogenicity of the fungus. Only the spray of RsCRZ1 dsRNA, but not RsPG1 or RsCATA dsRNA, affected fungal sclerotium formation. dsRNA stability on leaf surfaces and its efficiency in entering leaf cells were significantly improved when dsRNAs were loaded on layered double hydroxide (LDH) nanosheets. Notably, the RsCRZ1-dsRNA-LDH approach showed stronger and more lasting effects than using RsCRZ1-dsRNA alone in controlling pathogen development. Together, this study provides a new potential method to control crop diseases caused by R. solani.
Assuntos
Oryza , Rhizoctonia , Rhizoctonia/genética , Doenças das Plantas/genética , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , RNA de Cadeia Dupla/genética , Oryza/genéticaRESUMO
Rhizoctonia solani AG1-IA is a necrotrophic fungus that causes rice sheath blight and results in severe yield and quality reductions in rice worldwide. Differences of genetic structure and fungicide sensitivity of the pathogen have significant effects on the severity and control effect of this disease in the field. To determine correlations among population genetic structure, geographic origin, growth rate, and fungicide resistance of the pathogen, 293 strains of R. solani were isolated from diseased rice collected from 13 cities of Jiangsu Province and five regions of China. Simple sequence repeat (SSR) molecular marker technology was used to analyze the genetic diversity of these strains, and a total of 74 bands were amplified by nine pairs of primers. Population genetic structure analysis showed that strains from Central China and northern Jiangsu had the highest Nei's gene diversity index and Shannon diversity index. The vast majority of strains grew fast with colony diameters of more than 60.0 mm cultured at 28 °C for 36 h. The half-maximal effective concentration (EC50) of them to tebuconazole, thifluzamide, and propiconazole varied â¼16.2-, 3.8-, and 7.5-fold. However, the genetic diversity of R. solani had no significant correlation with their geographic origin, growth rate or fungicide sensitivity.
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Fungicidas Industriais , Oryza , Fungicidas Industriais/farmacologia , Estruturas Genéticas , Genética Populacional , Oryza/microbiologia , Doenças das Plantas/microbiologia , RhizoctoniaRESUMO
Marfan syndrome is a heritable autosomal-dominant connective tissue disorder and it was typically caused by mutations in FBN1. However, the synonymous mutation was seldom recorded to be related to Marfan syndrome. Hereon, Multiplex ligation-dependent probe amplification failed to detect a copy number variant involving FBN1 but a synonymous mutation c.4773A > G (p.Gly1591Gly) was identified by NGS in exon 39. RNA was extracted from patient's aortic tissue and reverse polymerase chain reaction demonstrated the presence of a shortened mRNA transcript. Results of minigene models indicated that c.4773A > G was bona fide responsibility for the aberrant splicing pattern, and artificial mutations of c.4773A > C and c.4773A > T also gave rise to fragments with exon 39 entire skipped. Together, the novel synonymous mutations in c.4773 position (A > G, C, T), middle of exon 39 of FBN1 gene, was found to be associated with Marfan syndrome by altering the splicing pattern of pre-mRNA.
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Éxons , Fibrilina-1/genética , Síndrome de Marfan/genética , Mutação , Adulto , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Splicing de RNARESUMO
Propofol is one of the most extensively used intravenous anaesthetic agents, which has been found to improve the surgical intervention outcome of several types of cancer, including hepatocellular carcinoma (HCC). Additionally, in vitro and in vivo experiments have also indicated that propofol affects the biological behaviour of HCC. However, the underlying mechanisms of the surgical resection of HCC with propofol have not been fully understood. In the present study, we aimed to investigate the underlying mechanism of propofol inhibition of the growth and invasion of HCC cells. Our results showed that treatment with propofol suppressed the proliferation, invasion and migration of HCC in vitro. The subcutaneous xenograft tumour and orthotopic xenograft tumour experiments in nude mice showed that propofol significantly decreased tumour volumes, growth rates and the liver orthotopic xenograft tumour in vivo. Furthermore, the underlying mechanism investigations of the suppressive effects of propofol on HCC cells revealed that propofol treatment upregulated the expression levels of the candidate tumour suppressor miR-219-5p. Silencing of propofol-induced miR-219-5p using anti-miR-219-5p abrogated the inhibitory effects on the proliferation, migration and invasion of HCC cells exerted by propofol treatment. Additionally, we demonstrated that propofol reversed the epithelial-mesenchymal transition of Huh7 and SMMC7721 cells via miR-219-5p induction. The molecular mechanism behind these findings is that propofol-induced miR-219-5p inhibits HCC cell progression by targeting glypican-3 and subsequently results in the inhibition of Wnt/ß-catenin signalling. Taken together, our study provides new insights into the advantages of the surgical intervention of HCC with propofol anaesthetization.
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Anestésicos Intravenosos/farmacologia , Carcinoma Hepatocelular/patologia , Glipicanas/metabolismo , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Propofol/farmacologia , Animais , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Linfócitos T Auxiliares-Indutores/imunologia , Via de Sinalização Wnt/genética , Via de Sinalização Wnt/fisiologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Spleen tyrosine kinase (SYK) plays a critical role in immune cell signaling pathways and has been reported as a biomarker for human hepatocellular carcinoma (HCC). We sought to investigate the mechanism by which SYK promotes liver fibrosis and to evaluate SYK as a therapeutic target for liver fibrosis. We evaluated the cellular localization of SYK and the association between SYK expression and liver fibrogenesis in normal, hepatitis B virus (HBV)-infected, hepatitis C virus (HCV)-infected and non-alcoholic steatohepatitis (NASH) liver tissue (n=36, 127, 22 and 30, respectively). A polymerase chain reaction (PCR) array was used to detect the changes in transcription factor (TF) expression in hepatic stellate cells (HSCs) with SYK knockdown. The effects of SYK antagonism on liver fibrogenesis were studied in LX-2 cells, TWNT-4 cells, primary human HSCs, and three progressive fibrosis/cirrhosis animal models, including a CCL4 mouse model, and diethylnitrosamine (DEN) and bile duct ligation (BDL) rat models. We found that SYK protein in HSCs and hepatocytes correlated positively with liver fibrosis stage in human liver tissue. HBV or HCV infection significantly increased SYK and cytokine expression in hepatocytes. Increasing cytokine production further induced SYK expression and fibrosis-related gene transcription in HSCs. Up-regulated SYK in HSCs promoted HSC activation by increasing the expression of specific TFs related to activation of HSCs. SYK antagonism effectively suppressed liver fibrosis via inhibition of HSC activation, and decreased obstructive jaundice and reduced HCC development in animal models. Conclusion: SYK promotes liver fibrosis via activation of HSCs and is an attractive potential therapeutic target for liver fibrosis and prevention of HCC development. (Hepatology 2018).
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Células Estreladas do Fígado/efeitos dos fármacos , Indazóis/uso terapêutico , Cirrose Hepática Experimental/enzimologia , Pirazinas/uso terapêutico , Quinase Syk/metabolismo , Animais , Avaliação Pré-Clínica de Medicamentos , Células Hep G2 , Hepatócitos/enzimologia , Humanos , Indazóis/farmacologia , Cirrose Hepática Experimental/prevenção & controle , Masculino , Camundongos Endogâmicos C57BL , Pirazinas/farmacologia , Ratos , Quinase Syk/antagonistas & inibidoresRESUMO
Energy metabolism disorders have been shown to exert detrimental effects on the pathology of Alzheimer's disease (AD). The ginsenoside compound K (CK), a major intestinal metabolite underlying the pharmacological actions of orally administered ginseng, has an ameliorating effect against AD, but the relevant molecular mechanism remains unclear. We hypothesized that the improvement of AD by CK is mediated by the energy metabolism signaling pathway induced by amyloid ß peptide (Aß) and tested this hypothesis in HT22 cells. HT22 cells were incubated with CK and exposed to Aß. Cell viability was analyzed using the MTT assay. Cell growth curves were derived from real-time cell analysis. Apoptosis was determined by flow cytometry, Aß localization and expression by immunofluorescence, and ATP content by a specific assay kit. The expression of proteins related to the energy metabolism signaling pathway was analyzed using Western blotting. CK treatment improved cell viability, cell growth, and apoptosis induced by Aß, and the cellular localization and expression of Aß. Moreover, CK increased ATP content by promoting the activity of glucose transporters (GLUTs). Therefore, the neuroprotective effect of CK against Aß injury was mainly realized through the activation of the energy metabolism signaling pathway. CK treatment inhibits neuronal damage caused by Aß through the activation of the energy metabolism signaling pathway, revealing that CK might be one of the key bioactive ingredients of ginseng in the treatment of Alzheimer's disease and may serve as a preventive or therapeutic agent for Alzheimer's disease.
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Metabolismo Energético/efeitos dos fármacos , Ginsenosídeos/farmacologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , China , Ginsenosídeos/metabolismo , Camundongos , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
For a running freely land-vehicle strapdown inertial navigation system (SINS), the problems of self-calibration and attitude alignment need to be solved simultaneously. This paper proposes a complete alignment algorithm for the land vehicle navigation using Inertial Measurement Units (IMUs) and an odometer. A self-calibration algorithm is proposed based on the global observability analysis to calibrate the odometer scale factor and IMU misalignment angle, and the initial alignment and calibration method based on optimal algorithm is established to estimate the attitude and other system parameters. This new algorithm has the capability of self-initialization and calibration without any prior attitude and sensor noise information. Computer simulation results show that the performance of the proposed algorithm is superior to the extended Kalman filter (EKF) method during the oscillating attitude motions, and the vehicle test validates its advantages.
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Inertial Measurement Unit (IMU) calibration accuracy is easily affected by turntable errors, so the primary aim of this study is to reduce the dependence on the turntable's precision during the calibration process. Firstly, the indicated-output of the IMU considering turntable errors is constructed and with the introduction of turntable errors, the functional relationship between turntable errors and the indicated-output was derived. Then, based on a D-suboptimal design, a calibration method for simultaneously identifying the IMU error model parameters and the turntable errors was proposed. Simulation results showed that some turntable errors could thus be effectively calibrated and automatically compensated. Finally, the theoretical validity was verified through experiments. Compared with the traditional method, the method proposed in this paper can significantly reduce the influence of the turntable errors on the IMU calibration accuracy.
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Rice blast, caused by Magnaporthe oryzae, threatens rice production in most of the rice-growing areas in China, especially in regions that have grown Oryza sativa subsp. japonica in recent years. The use of resistance genes is the most effective and economical approach for blast control. In our study, a set of six near-isogenic lines (NIL) were developed by introgression of six resistance alleles of the Piz locus (Pi2, Pigm, Pi40, Pi9, Piz, and Pizt) into a blast-susceptible, high-yielding, high-quality japonica '07GY31' via marker-assisted backcross breeding. Artificial inoculation using 144 M. oryzae isolates collected from the lower region of the Yangtze River, China, revealed that most of the NIL, including NIL-Pi2, NIL-Pigm, NIL-Pi40, NIL-Pi9, and NIL-Pizt, exhibited broad-spectrum resistance against rice blast at the seedling stage, with resistance frequencies (RF) of 93.06 to 98.61%. NIL-Piz was an exception, with an RF of 21.53%, which was slightly higher than the recurrent parent 07GY31. NIL-Pi40 and NIL-Pigm had broad-spectrum resistance (RF of 93.33 and 71.67%, respectively) at the heading stage following inoculation of 60 isolates of M. oryzae. Field trials with artificial inoculation at the seedling and heading stage showed that NIL-Pigm and NIL-Pi40 were highly resistant in four locations under high disease pressure. NIL-Pizt showed effective resistance in three locations from Zhejiang and Jiangsu Provinces. This study shows that O. sativa subsp. japonica alleles of the Piz locus confer resistance to M. oryzae, and provides an effective method to enhance seedling and panicle blast resistance in rice plants in the lower region of the Yangtze River, China.
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Here, we report DNA-induced polymer segregation and DNA island formation in binary block copolymer assemblies. A DNA diblock copolymer of polymethyl acrylate-block-DNA (PMA-b-DNA) and a triblock copolymer of poly(butadiene)-block-poly(ethylene oxide)-block-DNA (PBD-b-PEO-b-DNA) were synthesized, and each was coassembled with a prototypical amphiphilic polymer of poly(butadiene)-block-poly(ethylene oxide) (PBD-b-PEO). The binary self-assembly of PMA-b-DNA and PBD-b-PEO resulted in giant polymersomes with DNA uniformly distributed in the hydrophilic PEO shell. When giant polymersomes were connected through specific DNA interactions, DNA block copolymers migrated to the junction area, forming DNA islands within polymersomes. These results indicate that DNA hybridization can induce effective lateral polymer segregation in mixed polymer assemblies. The polymer segregation and local DNA enrichment have important implications in DNA melting properties, as mixed block copolymer assemblies with low DNA block copolymer contents can still exhibit useful DNA melting properties that are characteristic of DNA nanostructures with high DNA density.
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DNA/química , Bicamadas Lipídicas/química , Polietilenoglicóis/química , Polímeros/química , Acrilatos , Eletroforese em Gel de Poliacrilamida , Interações Hidrofóbicas e Hidrofílicas , Micelas , Microscopia Confocal , Nanoestruturas/química , Poliésteres/química , Água/químicaRESUMO
OBJECTIVES: This study compared splenectomy, partial splenic embolization, and high-intensity focused ultrasound (HIFU) therapy, which represent the traditional, mature, and newest methods for improving thrombocytopenia in hypersplenism, respectively. METHODS: A total of 69 patients with hypersplenism were treated with surgical splenectomy (n = 31), HIFU (n = 26), or partial splenic embolization (n = 12). They were followed closely for at least 6 months, and the effectiveness of the treatments was compared. RESULTS: Among the 3 groups, splenectomy was the most effective treatment for increasing peripheral blood cells. Embolization reduced the operating time and hospital stay, but HIFU was relatively safer and less invasive than the other treatments. CONCLUSIONS: High-intensity focused ultrasound has wide clinical indications for hypersplenism and may be safer than other treatment methods. Therefore, it is a good alternative procedure for patients with a high surgical risk.
Assuntos
Embolização Terapêutica/métodos , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Hiperesplenismo/diagnóstico , Hiperesplenismo/terapia , Duração da Cirurgia , Esplenectomia/métodos , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do TratamentoRESUMO
OBJECTIVE: The study was aimed at understanding the roles of polygalacturonases in the pathogenicity and the interaction between Rhizoctonia solani and rice. METHODS: According to the sequences of Rspg1 of R. solani deposited in GenBank, a pair of specific primers was designed. The gene Rspg1 was cloned and expressed using prokaryotic expression tool to elucidate its biological characteristics. The structures of the protein RsPG1 were predicted using bioinformatics tools. RESULTS: A 1395-bp fragment including an open reading frame (OFR) of Rspg1 was amplified from the genomic DNA of the pathogen. Compared with RT-PCR results, it was found that this sequence fragment contains five introns (positions 278-334, 545-601, 657-715, 1090-1155 and 1244-1304) and one 1095 bp ORF. The ORF was predicted to encode 364 amino acids. Bioinformatics analysis showed that RsPG1 contains an 18-amino acid signal peptide and 4 conserved sequence segments (180NTD, 202DD, 223GHG and 255RIK) characteristic of all the polygalacturonases. The main structural elements of the secondary structure are alpha-helix, beta-sheet and random coil. Six cysteines form three disulfide bonds (Cys24-Cys40, Cys204-Cys220 and Cys329-Cys333). Transmembrane prediction analysis suggested that RsPG1 could be secreted outside the cell. Tertiary structure is a right-handed helix which consisted of ten repeated beta-sheet, forming an opening activity cleft. CONCLUSION: RsPG1 is tentatively a 40 kDa protein with polygalacturonase enzyme activity at 277.78 U/mg. It is probably a secreted protein and has characteristics of all the polygalacturonases. The results can help to further understand the roles that R. solani polygalacturonases play during the pathogenicity and how the pathogen interacts with the host.
Assuntos
Clonagem Molecular , Proteínas Fúngicas/genética , Poligalacturonase/genética , Rhizoctonia/enzimologia , Sequência de Aminoácidos , Biologia Computacional , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Dados de Sequência Molecular , Oryza/microbiologia , Filogenia , Doenças das Plantas/microbiologia , Poligalacturonase/química , Poligalacturonase/metabolismo , Estrutura Terciária de Proteína , Rhizoctonia/classificação , Rhizoctonia/genética , Rhizoctonia/patogenicidade , VirulênciaRESUMO
BACKGROUND: Mutations in fibrillin-1 (FBN1) are known to be associated with Marfan syndrome (MFS), an autosomal dominant connective tissue disorder. Most FBN1 mutations are missense or nonsense mutations. Traditional molecular genetic testing for the FBN1 gene, like Sanger sequencing, may miss disease-causing mutations in the gene's regulatory regions or non-coding sequences, as well as partial or complete gene deletions and duplications. METHODS: Next-generation sequencing, multiplex ligation-dependent probe amplification and gap PCR were conducted on two MFS patients to screen for disease-causing mutations. RESULTS: We identified two large deletions in FBN1 from two MFS patients. One patient had a 0.23 Mb deletion (NC_000015.9:g.48550506_48779360del) including 5'UTR-exon6 of FBN1. The other patient harbored a 1416 bp deletion (NC_000015.9:g.48410869_48412284del) affecting the last exon, exon 66, of the FBN1 gene. CONCLUSION: Our results expanded the number of large FBN1 deletions and highlighted the importance of screening for large deletions in FBN1 in clinical genetic testing, especially for those with the classic MFS phenotype.