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The volume of ribonucleic acid (RNA)-seq data has increased exponentially, providing numerous new insights into various biological processes. However, due to significant practical challenges, such as data heterogeneity, it is still difficult to ensure the quality of these data when integrated. Although some quality control methods have been developed, sample consistency is rarely considered and these methods are susceptible to artificial factors. Here, we developed MassiveQC, an unsupervised machine learning-based approach, to automatically download and filter large-scale high-throughput data. In addition to the read quality used in other tools, MassiveQC also uses the alignment and expression quality as model features. Meanwhile, it is user-friendly since the cutoff is generated from self-reporting and is applicable to multimodal data. To explore its value, we applied MassiveQC to Drosophila RNA-seq data and generated a comprehensive transcriptome atlas across 28 tissues from embryogenesis to adulthood. We systematically characterized fly gene expression dynamics and found that genes with high expression dynamics were likely to be evolutionarily young and expressed at late developmental stages, exhibiting high nonsynonymous substitution rates and low phenotypic severity, and they were involved in simple regulatory programs. We also discovered that human and Drosophila had strong positive correlations in gene expression in orthologous organs, revealing the great potential of the Drosophila system for studying human development and disease.
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Drosophila melanogaster , Transcriptoma , Humanos , Animales , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Perfilación de la Expresión Génica/métodos , ARN/genética , RNA-Seq , Análisis de Secuencia de ARN , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , DrosophilaRESUMEN
INTRODUCTION AND OBJECTIVES: In a recent development, a cohort of hepatologists has proposed altering the nomenclature of non-alcoholic fatty liver disease (NAFLD) to metabolic-associated steatotic liver disease (MASLD), accompanied by modified diagnostic criteria. Our objective was to investigate the effect of the revised definition on identifying significant hepatic fibrosis. PATIENTS AND METHODS: From Jan 2009 to Dec 2022, a total of 428 patients with biopsy-proven hepatic steatosis were diagnosed with NAFLD. Patients were classified into subgroups according to MASLD and Cryptogenic-SLD diagnostic criteria. The clinical pathological features were compared between these two groups. Risk factors for significant fibrosis were analysed in the MASLD group. In total, 329 (76.9 %) patients were diagnosed with MASLD, and 99 (23.1 %) were diagnosed with Cryptogenic-SLD. RESULTS: Those with MASLD exhibited a higher degree of disease severity regarding histology features than Cryptogenic-SLD. The prevalence of significant fibrosis increased from 13 % to 26.6 % for one and two criteria present to 42.5 % for meeting three or more cardiometabolic risk factor (CMRF) criteria (p = 0.001). ALB (aOR:0.94,95 %CI:0.90-1.00; p = 0.030), lower levels of PLT (aOR:0.99, 95 %CI:0.99-1.00; p < 0.001), and more metabolic comorbidities (aOR:1.42,95 %CI:1.14-1.78; p = 0.012) were independent risk factors of significant fibrosis in MASLD. CONCLUSIONS: The new nomenclature of MASLD and SLD is more applicable to identifying significant fibrosis than NAFLD. Patients with three or more cardiometabolic risk factors are at higher risk of fibrosis.
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Enfermedades Metabólicas , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedades Metabólicas/diagnóstico , Enfermedades Metabólicas/epidemiología , Comorbilidad , Factores de Riesgo , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/epidemiologíaRESUMEN
Crop rotation can assemble distinct core microbiota as functionally specific barriers against the invasion of banana Fusarium oxysporum pathogens. However, the taxonomic identity of rotation-unique core taxa and their legacy effects are poorly understood under field conditions. Pepper and eggplant rotations were employed to reveal rotation crop- and banana-unique antagonistic core taxa by in situ tracking of the soil microbiome assembly patterns for 2 yr. The rotation crop-unique antagonistic taxa were isolated and functionally verified by culture-dependent techniques, high-throughput sequencing, and pot experiments. Pepper and eggplant rotations resulted in eight and one rotation-unique antagonistic core taxa out of 12 507 microbial taxa, respectively. These nine antagonistic taxa were retained the following year and significantly decreased banana wilt disease incidence via legacy effects, although the cultivated strains were exclusively of the genera Bacillus and Pseudomonas. The fermentation broth and volatiles of these two taxa showed strong antagonistic activity, and pot experiments demonstrated high suppression of wilt disease and significant promotion of banana growth. Our study provides a mechanistic understanding of the identification of rotation crop-unique antagonistic taxa and highlights the importance of targeted cultivation of beneficial microorganisms for optimizing crop rotation-based scenarios in support of banana agriculture sustainability.
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Fusarium , Microbiota , Musa , Bacterias , Rizosfera , Productos Agrícolas , Enfermedades de las Plantas , Microbiología del SueloRESUMEN
Developing non-fullerene acceptors (NFAs) by modifying the backbone, side chains and end groups is the most important strategy to improve the power conversion efficiency of organic solar cells (OSCs). Among numerous developed NFAs, Y6 and its derivatives are famous NFAs in the OSC field due to their good performance. Herein, in order to understand the mechanism of tuning the photovoltaic performance by modifying the Y6's center backbone, π-spacer and side-chains, we selected the PM6:Y6 OSC as a reference and systematically studied PM6:AQx-2, PM6:Y6-T, PM6:Y6-2T, PM6:Y6-O, PM6:Y6-1O and PM6:Y6-2O OSC systems based on extensive quantum chemistry calculations. The results indicate that introducing quinoxaline to substitute thiadiazole in the backbone induces a blue-shift of absorption spectra, reduces the charge transfer (CT) distance (Δd) and average electrostatic potential (ESP), and increases the singlet-triplet energy gap (ΔEST), CT excitation energy and the number of CT states in low-lying excitations. Inserting thienyl and dithiophenyl as π spacers generates a red-shift of absorption spectra, enlarges Δd and average ESP, and reduces ΔEST and the number of CT states. Introducing furo[3,2-b]furan for substituting one thieno[3,2-b]thiophene unit in the Y6's backbone causes a red-shift of absorption spectra and increases ΔEST, Δd and average ESP as well as CT excitation energy. Introducing alkoxyl as a side chain results in a blue-shift of absorption spectra, and increases ΔEST, Δd, average ESP, CT excitation energy and the number of CT states. The rate constants calculated using Marcus theory suggest that all the molecular modifications of Y6 reduce the exciton dissociation and charge recombination rates at the heterojunction interface, while introducing furo[3,2-b]furan and alkoxyl enlarges CT rates.
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Aberrant activation of NLRP3 inflammasome causes the progression of various inflammation-related diseases, but the small-molecule inhibitors of NLRP3 are not currently available for clinical use. Tabersonine (Tab) is a natural product derived from a traditional Chinese herb Catharanthus roseus that is usually used as an anti-tumor agent. In this study we investigated the anti-inflammatory effects and molecular targets of Tab. We first screened 151 in-house natural compounds for their inhibitory activity against IL-1ß production in BMDMs. We found that Tab potently inhibited NLRP3-mediated IL-1ß production with an IC50 value of 0.71 µM. Furthermore, we demonstrated that Tab suppressed the assembly of NLRP3 inflammasome, especially the interaction between NLRP3 and ASC. Interestingly, we found that Tab directly bound to NLRP3 NACHT domain, thereby reducing the self-oligomerization of NLRP3. In addition, we showed that administration of Tab significantly ameliorated NLRP3-driven diseases, such as peritonitis, acute lung injury, and sepsis in mouse models. The preventive effects of Tab were not observed in the models of NLRP3 knockout mouse. In conclusion, we have identified Tab as a natural NLRP3 inhibitor and a lead compound for the design and discovery of novel NLRP3 inhibitors.
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Inflamasomas , Quinolinas , Animales , Ratones , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Macrófagos , Quinolinas/farmacología , Interleucina-1beta/metabolismo , Ratones Endogámicos C57BL , Lipopolisacáridos/farmacologíaRESUMEN
Dengue virus (DV) has occasionally emerged at epidemic levels in Yunnan, China. Vaccine development is limited by antibody-dependent enhancement and a lack of good animal models. Thus, the study investigated cross infection based on maternal immunity in BALB/c mice and assessed the risk of cross infection by DV2-D13113 and DV3-YNWS2 epidemic virus strains. DV replicated within the organs of the BALB/c infant mice, even causing death. Particularly, DV3-infected infant mice were at higher risk of severe disease if their mothers were infected with DV2. Although BALB/c adults and pups survived DV2/DV3 infection and produced anti-DV antibodies after 5-8 days, extensive subcutaneous vascular leakage was observed after secondary DV infection. Furthermore, vascular permeability in the lung and kidney significantly increased in offspring born to heterotypic virus-infected mothers. Thus, vascular leakage indicates severe DV infection. The results indicate that maternal immunity increases the severity of subsequent heterotypic infection. Additionally, secondary cross infection by D13113 and YNWS2 represents a risk of serious disease. This study has implications for studies of DV cross infection and vaccine development.
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Coinfección , Infección Hospitalaria , Virus del Dengue , Dengue , Animales , Anticuerpos Antivirales , China , Humanos , Ratones , Ratones Endogámicos BALB C , SerogrupoRESUMEN
A novel bacterial strain, CH91, was isolated from a high-temperature oil reservoir. Morphological characterization, phylogenetic analyses of 16S rRNA gene sequence and genome relatedness indicated that the strain is a potential new species in the genus Rhodococcus. Strain CH91 could grow in the temperature range of 25-50 °C (optimally at 37 °C) and utilize a broad range of long-chain n-alkanes from hexadecane to hexatriacontane. The utilization of the n-alkanes mixture of strain CH91 revealed that the degradation rate was correlated to the length of the carbon chain. Two novel alkB genes encoding alkane 1-monooxygenase were found in the genome of this strain. The protein sequences of both alkane 1-monooxygenases showed a remarkable phylogenetic distance to other reported AlkB protein sequences. These results would help broaden our knowledge about alkane degradation by Rhodocuccus and its potential ecological role. The ability of the strain in the long-chain alkane degradation and thermal tolerance could also be further exploited for bioremediation of oil contaminations and microbial enhanced oil recovery.
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Rhodococcus , Alcanos/metabolismo , Biodegradación Ambiental , Citocromo P-450 CYP4A/genética , Filogenia , ARN Ribosómico 16S/genética , Rhodococcus/genética , Rhodococcus/metabolismo , Análisis de Secuencia de ADNRESUMEN
Protoporphyrinogen IX (Protogen IX) oxidase (PPO) catalyzes the oxidation of Protogen IX to Proto IX. PPO is also the target site for diphenyl ether-type herbicides. In plants, there are two PPO encoding genes, PPO1 and PPO2. To date, no PPO gene or mutant has been characterized in monocotyledonous plants. In this study, we isolated a spotted and rolled leaf (sprl1) mutant in rice (Oryza sativa). The spotted leaf phenotype was sensitive to high light intensity and low temperature, but the rolled leaf phenotype was insensitive. We confirmed that the sprl1 phenotypes were caused by a single nucleotide substitution in the OsPPO1 (LOC_Os01g18320) gene. This gene is constitutively expressed, and its encoded product is localized to the chloroplast. The sprl1 mutant accumulated excess Proto(gen) IX and reactive oxygen species (ROS), resulting in necrotic lesions. The expressions of 26 genes associated with tetrapyrrole biosynthesis, photosynthesis, ROS accumulation, and rolled leaf were significantly altered in sprl1, demonstrating that these expression changes were coincident with the mutant phenotypes. Importantly, OsPPO1-overexpression transgenic plants were resistant to the herbicides oxyfluorfen and acifluorfen under field conditions, while having no distinct influence on plant growth and grain yield. These finding indicate that the OsPPO1 gene has the potential to engineer herbicide resistance in rice.
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Herbicidas , Oryza , Resistencia a los Herbicidas/genética , Herbicidas/farmacología , Mutación , Oryza/genética , Oryza/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Protoporfirinógeno-Oxidasa/genética , Protoporfirinógeno-Oxidasa/metabolismo , Especies Reactivas de OxígenoRESUMEN
Nesfatin-1 (encoded by NUCB2) is a cardiac peptide possessing protective activities against myocardial ischaemia/reperfusion (MI/R) injury. However, the regulation of NUCB2/nesfatin-1 and the molecular mechanisms underlying its roles in MI/R injury are not clear. Here, by investigating a mouse MI/R injury model developed with transient myocardial ischaemia followed by reperfusion, we found that the levels of NUCB2 transcript and nesfatin-1 amount in the heart were both decreased, suggesting a transcriptional repression of NUCB2/nesfatin-1 in response to MI/R injury. Moreover, cardiac nesfatin-1 restoration reduced infarct size, troponin T (cTnT) level and myocardial apoptosis, supporting its cardioprotection against MI/R injury in vivo. Mechanistically, the Akt/ERK pathway was activated, and in contrast, endoplasmic reticulum (ER) stress was attenuated by nesfatin-1 following MI/R injury. In an in vitro system, similar results were obtained in nesfatin-1-treated H9c2 cardiomyocytes with hypoxia/reoxygenation (H/R) injury. More importantly, the treatment of wortmannin, an inhibitor of Akt/ERK pathway, abrogated nesfatin-1 effects on attenuating ER stress and H/R injury in H9c2 cells. Furthermore, nesfatin-1-mediated protection against H/R injury also vanished in the presence of tunicamycin (TM), an ER stress inducer. Lastly, Akt/ERK inhibition reversed nesfatin-1 effects on mouse ER stress and MI/R injury in vivo. Taken together, these findings demonstrate that NUCB2/nesfatin-1 inhibits MI/R injury through attenuating ER stress, which relies on Akt/ERK pathway activation. Hence, our study provides a molecular basis for understanding how NUCB2/nesfatin-1 reduces MI/R injury.
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Estrés del Retículo Endoplásmico , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación de la Expresión Génica , Daño por Reperfusión Miocárdica/prevención & control , Miocitos Cardíacos/metabolismo , Nucleobindinas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Proliferación Celular , Células Cultivadas , Quinasas MAP Reguladas por Señal Extracelular/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Daño por Reperfusión Miocárdica/etiología , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Nucleobindinas/genética , Proteínas Proto-Oncogénicas c-akt/genéticaRESUMEN
Diverse metabolic changes are induced by various driver oncogenes during the onset and progression of leukemia. By upregulating glycolysis, cancer cells acquire a proliferative advantage over normal hematopoietic cells; in addition, these changes in energy metabolism contribute to anticancer drug resistance. Because leukemia cells proliferate by consuming glucose as an energy source, an alternative nutrient source is essential when glucose levels in bone marrow are insufficient. We profiled sugar metabolism in leukemia cells and found that mannose is an energy source for glycolysis, the tricarboxylic acid (TCA) cycle, and the pentose phosphate pathway. Leukemia cells express high levels of phosphomannose isomerase (PMI), which mobilizes mannose to glycolysis; consequently, even mannose in the blood can be used as an energy source for glycolysis. Conversely, suppression of PMI expression or a mannose load exceeding the processing capacity of PMI inhibited transcription of genes related to mitochondrial metabolism and the TCA cycle, therefore suppressing the growth of leukemia cells. High PMI expression was also a poor prognostic factor for acute myeloid leukemia. Our findings reveal a new mechanism for glucose starvation resistance in leukemia. Furthermore, the combination of PMI suppression and mannose loading has potential as a novel treatment for driver oncogene-independent leukemia.
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Leucemia/tratamiento farmacológico , Manosa-6-Fosfato Isomerasa/metabolismo , Manosa/administración & dosificación , Regulación hacia Arriba , Animales , Línea Celular Tumoral , Ciclo del Ácido Cítrico/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucólisis/efectos de los fármacos , Humanos , Células K562 , Leucemia/enzimología , Leucemia/genética , Leucemia/patología , Manosa/farmacología , Manosa-6-Fosfato Isomerasa/antagonistas & inhibidores , Ratones , Vía de Pentosa Fosfato/efectos de los fármacos , Pronóstico , Células THP-1 , Regulación hacia Arriba/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
OBJECTIVE: This study aimed to compare the long-term outcome of endotherapy versus a combination of splenectomy and devascularization for variceal bleeding in patients with hepatitis B-related cirrhosis (HBRC). MATERIALS AND METHODS: A total of 1074 patients with HBRC and acute variceal bleeding (AVB) treated with endotherapy and 248 patients with HBRC treated with a combination of splenectomy and devascularization surgery were included in the analysis. After one-to-one propensity score matching, 151 paired patients were selected. The primary end-point was death. The secondary outcomes were 3-year survival, 5-year survival, and rebleeding. Complications were recorded. RESULTS: The median follow-up time was 1165 days in the endoscopic group and 1709 days in the surgical group. Before matching, the 1-year, 3-year, and 5-year survival rates were significantly lower in the endoscopic group than in the surgical group (91.1 vs 96.3%, P = 0.017; 79.6 vs 91.6%, P = 0.001; 65.2 vs 81.3%, P = 0.001). After matching, no significant differences were found between groups (94.5 vs 95.2%, P = 0.767; 87.0 vs 88.9%, P = 0.635; 77.9 vs 77.9%, P = 0.905). The rebleeding rate was lower in the surgical group than in the endoscopic group; the rebleeding-free survival rate was similar in the two groups. No patient died of complications. No statistically significant difference was observed in complications between groups. CONCLUSIONS: Both endotherapy and a combination of splenectomy and devascularization are good choices for patients with AVB. The rebleeding rate was lower after the surgical procedure, but the long-term prognosis was similar.
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Várices Esofágicas y Gástricas , Hepatitis B , Várices Esofágicas y Gástricas/complicaciones , Várices Esofágicas y Gástricas/cirugía , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/cirugía , Hepatitis B/complicaciones , Humanos , Cirrosis Hepática/complicaciones , Recurrencia Local de Neoplasia , Pronóstico , Recurrencia , Esplenectomía , Resultado del TratamientoRESUMEN
Although the telomeric sequence has been reported to form various G-quadruplex topologies in vitro and in Xenopus laevis oocytes, in living human cells, the topology of telomeric DNA G-quadruplex remains a challenge. To investigate the human telomeric DNA G-quadruplex in a more realistic human cell environment, in the present study, we demonstrated that the telomeric DNA sequence can form two hybrid-type and two-tetrad antiparallel G-quadruplex structures by in-cell 19F NMR in living human cells (HELA CELLS). This result provides valuable information for understanding the structures of human telomeric DNA in living human cells and for the design of new drugs that target telomeric DNA.
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ADN/química , G-Cuádruplex , Telómero/genética , Termodinámica , Dicroismo Circular , ADN/genética , ADN/metabolismo , Flúor/química , Células HeLa , Humanos , Modelos Moleculares , Espectroscopía de Protones por Resonancia MagnéticaRESUMEN
The cross combination of dry-method(network pharmacology analysis) and wet-method(high-resolution mass spectro-metry with antioxidation experiment) was used to predict antioxidant quality markers(Q-markers) of Hippophae tibetana. Ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap mass spectrometry(UPLC-Q-Exactive Orbitrap-MS) was developed to rapidly separate and identify the chemical constituents in H. tibetana. Then in DPPH free radicals and superoxide anion scavenging experiment, the antioxidant activity of the four different polar parts with extracts of petroleumether, ethyl acetate, n-butanol and water was evaluated. Network pharmacology method was used for functional enrichment and pathway analysis to screen antioxidant-related components and preliminarily explain the mechanism of action. On this basis, multi-source information was integrated to predict the antioxidant Q-markers. The results showed that 51 components in H. tibetana were identified, including 18 flavonoids, 14 terpenoids, 6 alkaloids, 4 coumarins and phenylpropanoids, 3 volatile components and 2 polyphenols. The antioxidant capacity of different fractions: ethyl acetate > n-butanol > water > petroleum ether. The medicine mainly acted on PI3 K-Akt and FoxO signaling pathways to perform antioxidant effects through flavonoids such as quercetin, luteolin and kaempferol. According to the results of dry-method and wet-method, quercetin, luteolin and kaempferol, the representatives of poly-hydroxy flavone, may be the antioxidant Q-markers of H. tibetana. In this study, with the antioxidant Q-markers of H. tibetana as an example, an investigation model of predicting Q-marker was discussed based on the ternary system of composition, function and informatics, providing a scientific basis for the establishment of quality evaluation standards for H. tibetana.
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Antioxidantes , Hippophae , Cromatografía Líquida de Alta Presión , Espectrometría de Masas , TecnologíaRESUMEN
BACKGROUND: To understand the gene expression networks controlling flower color formation in alfalfa, flowers anthocyanins were identified using two materials with contrasting flower colors, namely Defu and Zhongtian No. 3, and transcriptome analyses of PacBio full-length sequencing combined with RNA sequencing were performed, across four flower developmental stages. RESULTS: Malvidin and petunidin glycoside derivatives were the major anthocyanins in the flowers of Defu, which were lacking in the flowers of Zhongtian No. 3. The two transcriptomic datasets provided a comprehensive and systems-level view on the dynamic gene expression networks underpinning alfalfa flower color formation. By weighted gene coexpression network analyses, we identified candidate genes and hub genes from the modules closely related to floral developmental stages. PAL, 4CL, CHS, CHR, F3'H, DFR, and UFGT were enriched in the important modules. Additionally, PAL6, PAL9, 4CL18, CHS2, 4 and 8 were identified as hub genes. Thus, a hypothesis explaining the lack of purple color in the flower of Zhongtian No. 3 was proposed. CONCLUSIONS: These analyses identified a large number of potential key regulators controlling flower color pigmentation, thereby providing new insights into the molecular networks underlying alfalfa flower development.
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Flores/fisiología , Expresión Génica , Redes Reguladoras de Genes , Genes de Plantas , Medicago sativa/fisiología , Pigmentación/genética , Flores/genética , Medicago sativa/genética , RNA-SeqRESUMEN
The live attenuated hepatitis A virus vaccine (HA-L) is in routine use in the Chinese national immunization program (NIP). The major disadvantages of HA-L include that theoretically, it may be possible for mutation shifts and secondary infections of the live vaccine viral strain. The aim of this study was to explore variation in the viral strain after vaccination with the HA-L. A total of 1297 fecal samples (including 470 for the 18 to 36-month-old age group, 527 for the 3 to 16-year-old group, and 300 for the 16 years and older group) were collected in the study, and the rate of hepatitis A virus (HAV) positivity in fecal samples was 11.36% (31/273), 11.44% (31/271), 9.70% (26/268), 8.47% (21/248), and 9.70% (23/237) on days 0, 7, 14, 21 and 28, respectively. A total of 77 HAV positive samples were randomly selected for VP1/2A (360 bp, 2218-2577) gene analysis. Phylogenetic trees were then constructed by the neighbor-joining method. Phylogenetic analyses showed that all the isolated HAV strains belonged to sub-genotype IB, which was the same as the vaccine strain. Compared with the vaccine strain, HM-175/7MK-5 (M16632.1), there were only two base mutations discovered, at 2291 and 2568. However, the amino acid mutation analysis showed that those base mutations were synonymous mutations. The isolated HAV strains were genetically stable. This study provides a reference for the safety concern regarding the routine and wide-range use in people older than 18 months.
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Although the alteration of DNA methylation due to abiotic stresses, such as exposure to the toxic metal cadmium (Cd), has been often observed in plants, little is known about whether such epigenetic changes are linked to the ability of plants to adapt to stress. Herein, we report a close linkage between DNA methylation and the adaptational responses in Arabidopsis plants under Cd stress. Exposure to Cd significantly inhibited the expression of three DNA demethylase genes ROS1/DML2/DML3 (RDD) and elevated DNA methylation at the genome-wide level in Col-0 roots. Furthermore, the profile of DNA methylation in Cd-exposed Col-0 roots was similar to that in the roots of rdd triple mutants, which lack RDD, indicating that Cd-induced DNA methylation is associated with the inhibition of RDD. Interestingly, the elevation in DNA methylation in rdd conferred a higher tolerance against Cd stress and improved cellular Fe nutrition in the root tissues. In addition, lowering the Fe supply abolished improved Cd tolerance due to the lack of RDD in rdd. Together, these data suggest that the inhibition of RDD-mediated DNA demethylation in the roots by Cd would in turn enhance plant tolerance to Cd stress by improving Fe nutrition through a feedback mechanism.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Cadmio/toxicidad , Desmetilación del ADN , Tolerancia a Medicamentos/fisiología , Hierro/metabolismo , Adaptación Fisiológica , Arabidopsis/efectos de los fármacos , Proteínas de Arabidopsis/genética , Cadmio/metabolismo , ADN Glicosilasas/metabolismo , Metilación de ADN , Elementos Transponibles de ADN , Tolerancia a Medicamentos/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Genes de Plantas , Mutación , Proteínas Nucleares/metabolismo , Raíces de Plantas/metabolismo , Estrés FisiológicoRESUMEN
Due to the role of dyes in dye-sensitized solar cells (DSSCs), designing novel dye sensitizers is an effective strategy to improve the power conversion efficiency. To this end, the fundamental issue is understanding the sensitizer's trilateral relationship among its molecular structure, optoelectronic properties, and photovoltaic performance. Considering the good performance of N-annulated perlyene dye sensitizers, the geometries, electronic structures, and excitations of the selected representative organic dye sensitizers C276, C277, and C278 as well as dyes adsorbed on TiO2 clusters were calculated in order to investigate the relationship between molecular structures and properties. It was found that fusing thienyl to N-annulated perlyene can elevate the highest occupied molecular orbital (HOMO) energy, reduce the orbital energy gap, increase the density of states, expand the HOMO to the benzothiadiazole moiety, enhance the charge transfer excitation, elongate the fluorescence lifetime, amplify the light harvesting efficiency, and induce a red-shift of the absorption spectra. The transition configurations and molecular orbitals of the dye-adsorbed systems support that the electron injection in DSSCs based on these dyes is a fast mode. Based on extensive analysis of the electronic structures and excitation properties of these dye sensitizers and the dye-adsorbed systems, we present new quantities as open-circuit voltage and short-circuit current density descriptors that celebrate the quantitative bridge between the photovoltaic parameters and the electronic structure-related properties in order to expose the relationship between properties and performance. The results of this work are critical for the design of novel dye sensitizers for solar cells.
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INTRODUCTION AND OBJECTIVES: The predictors for gastroesophageal varices (GOV) and hemorrhage development have not been well studied in different liver diseases or different population. This study aimed to evaluate whether a new algorithm focusing on chronic hepatitis B (CHB) patients is also applicable to other chronic liver diseases (CLDs) in Chinese population. PATIENTS OR MATERIALS AND METHODS: We retrospectively analyzed 659 CHB patients and 386 patients with other CLDs. A total of 439 CHB patients were included in training set, the other 220 CHB patients and other patients with CLDs were included in validation set. A new algorithm for diagnosing GOV was established and its sensitivity and specificity for predicting the varices was verified. RESULTS: Multivariable logistic regression revealed that the rough surface of the liver (p<0.001), splenic thickness (p<0.001), and liver stiffness (p=0.006) were independent predictors of GOV. The new algorithm was considered to be a reliable diagnostic model to evaluate the presence of varices. The AUROC was 0.94 (p<0.001) in CHB validation set and 0.90 (<0.001) in non-CHB validation set. When the cut-off value was chosen as -1.048, the sensitivity and specificity in diagnosing GOV in CHB population were 89.1% and 82.5%, respectively. Importantly, the new algorithm accurately predicted the variceal hemorrhage not only in CHB patients, but also in patients with other CLDs. CONCLUSION: The new algorithm is regarded as a reliable model to prognosticate varices and variceal hemorrhage, and stratified not only the high-risk CHB patients, but also in patients with other CLDs for developing GOV and variceal bleeding.
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Várices Esofágicas y Gástricas/diagnóstico , Hemorragia Gastrointestinal/diagnóstico , Hepatitis B Crónica/epidemiología , Cirrosis Hepática/epidemiología , Adulto , Algoritmos , Área Bajo la Curva , China/epidemiología , Diagnóstico por Imagen de Elasticidad , Endoscopía del Sistema Digestivo , Várices Esofágicas y Gástricas/epidemiología , Várices Esofágicas y Gástricas/etiología , Femenino , Hemorragia Gastrointestinal/epidemiología , Hemorragia Gastrointestinal/etiología , Hepatitis B Crónica/complicaciones , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico por imagen , Hepatopatías/complicaciones , Hepatopatías/diagnóstico por imagen , Hepatopatías/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Tamaño de los Órganos , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Bazo/diagnóstico por imagen , Bazo/patologíaRESUMEN
The iron-sulfur subunit (SDH2) of succinate dehydrogenase plays a key role in electron transport in plant mitochondria. However, it is yet unknown whether SDH2 genes are involved in leaf senescence and yield formation. In this study, we isolated a late premature senescence mutant, lps1, in rice (Oryza sativa). The mutant leaves exhibited brown spots at late tillering stage and wilted at the late grain-filling stage and mature stage. In its premature senescence leaves, photosynthetic pigment contents and net photosynthetic rate were reduced; chloroplasts and mitochondria were degraded. Meanwhile, lps1 displayed small panicles, low seed-setting rate and dramatically reduced grain yield. Gene cloning and complementation analysis suggested that the causal gene for the mutant phenotype was OsSDH2-1 (LOC_Os08g02640), in which single nucleotide mutation resulted in an amino acid substitution in the encoded protein. OsSDH2-1 gene was expressed in all organs tested, with higher expression in leaves, root tips, ovary and anthers. OsSDH2-1 protein was targeted to mitochondria. Furthermore, reactive oxygen species (ROS), mainly H2O2, was excessively accumulated in leaves and young panicles of lps1, which could cause premature leaf senescence and affect panicle development and pollen function. Taken together, OsSDH2-1 plays a crucial role in leaf senescence and yield formation in rice.
Asunto(s)
Envejecimiento/genética , Proteínas Hierro-Azufre/genética , Oryza/genética , Desarrollo de la Planta/genética , Hojas de la Planta/genética , Subunidades de Proteína/genética , Succinato Deshidrogenasa/genética , Cloroplastos/ultraestructura , Grano Comestible , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Proteínas Hierro-Azufre/metabolismo , Mutación , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Fenotipo , Fotosíntesis/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Subunidades de Proteína/metabolismo , Carácter Cuantitativo Heredable , Especies Reactivas de Oxígeno/metabolismo , Reproducción , Succinato Deshidrogenasa/metabolismoRESUMEN
In the present study, we used a nucleoside derivative 5-vinyluridine (VrU) for labeling during cell division and for tumor imaging in living mice. We demonstrated that the functional nucleoside bearing a 5-vinyl group is metabolically incorporated into cellular RNA and can be used to image RNA using a Diels-Alder reaction. The reagent allows for simultaneous and clear imaging of DNA and RNA in mammalian cells at single-cell resolution. We extended this approach to observe DNA and RNA behaviors in several basic stages of cell division. We further demonstrated that the derivative can be used for fluorescence imaging of tumor in live mice.