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Constant-frequency ultrasonic treatment helped to improve seed germination. However, variable-frequency ultrasonic treatment on maize seed germination were rarely reported. In this study, maize seeds were exposed to 20-40 kHz ultrasonic for 40 s. The germination percentage and radicle length of maize seeds increased by 10.4% and 230.5%. Ultrasonic treatment also significantly increased the acid protease, α-amylase, and ß-amylase contents by 96.4%, 73.8%, and 49.1%, respectively. Transcriptome analysis showed that 11,475 differentially expressed genes (DEGs) were found in the ultrasonic treatment and control groups, including 5,695 upregulated and 5,780 downregulated. Metabolic pathways and transcription factors (TFs) were significantly enriched among DEGs after ultrasonic treatment. This included metabolism and genetic information processing, that is, ribosome, proteasome, and pyruvate metabolism, sesquiterpenoid, triterpenoid, and phenylpropanoid biosynthesis, and oxidative phosphorylation, as well as transcription factors in the NAC, MYB, bHLH, WRKY, AP2, bZIP, and ARF families. Variable-frequency ultrasonic treatment increased auxin, gibberellin, and salicylic acid by 5.5%, 37.3%, and 28.9%, respectively. Abscisic acid significantly decreased by 33.2%. The related DEGs were upregulated and downregulated to varying degrees. Seed germination under the abiotic stress conditions of salt stress (NaCl solution), drought (PEG solution), and waterlogging (water-saturated sand bed) under ultrasonic treatment were promoted, radicle length was significantly increased by 30.2%, 30.5%, and 27.3%, respectively; and germination percentage by 14.8%, 20.1%, and 21.6%, respectively. These findings provide new insight into the mechanisms through ultrasonic to promote maize seed germination.
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Germinação , Sementes , Estresse Fisiológico , Zea mays , Zea mays/genética , Zea mays/fisiologia , Zea mays/crescimento & desenvolvimento , Germinação/efeitos da radiação , Sementes/efeitos da radiação , Sementes/crescimento & desenvolvimento , Sementes/genética , Sementes/fisiologia , Regulação da Expressão Gênica de Plantas , Perfilação da Expressão Gênica , Ondas Ultrassônicas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Enhancing root development is pivotal for boosting crop yield and augmenting stress resilience. In this study, we explored the regulatory effects of xylooligosaccharides (XOSs) on lettuce root growth, comparing their impact with that of indole-3-butyric acid potassium salt (IBAP). Treatment with XOS led to a substantial increase in root dry weight (30.77%), total root length (29.40%), volume (21.58%), and surface area (25.44%) compared to the water-treated control. These enhancements were on par with those induced by IBAP. Comprehensive phytohormone profiling disclosed marked increases in indole-3-acetic acid (IAA), zeatin riboside (ZR), methyl jasmonate (JA-ME), and brassinosteroids (BRs) following XOS application. Through RNA sequencing, we identified 3807 differentially expressed genes (DEGs) in the roots of XOS-treated plants, which were significantly enriched in pathways associated with manganese ion homeostasis, microtubule motor activity, and carbohydrate metabolism. Intriguingly, approximately 62.7% of the DEGs responsive to XOS also responded to IBAP, underscoring common regulatory mechanisms. However, XOS uniquely influenced genes related to cutin, suberine, and wax biosynthesis, as well as plant hormone signal transduction, hinting at novel mechanisms of stress tolerance. Prominent up-regulation of genes encoding beta-glucosidase and beta-fructofuranosidase highlights enhanced carbohydrate metabolism as a key driver of XOS-induced root enhancement. Collectively, these results position XOS as a promising, sustainable option for agricultural biostimulation.
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Introduction: Salt stress in seed germination and early seedling growth is the greatest cause of crop loss in saline-alkali soils. Microbial seed coating is an effective way to promote plant growth and salt resistance, but these coatings suffer from poor seed adhesion and low survival rates under typical storage conditions. Methods: In this study, the marine bacterium Pontibacter actiniarum DSM 19842 from kelp was isolated and microencapsulated with calcium alginate using the emulsion and internal gelation method. Results: Compared to unencapsulated seeds, the spherical microcapsules demonstrated a bacterial encapsulation rate of 65.4% and survival rate increased by 22.4% at 25°C for 60 days. Under salt stress conditions, the seed germination percentage of microcapsule-embedded bacteria (M-Embed) was 90%, which was significantly increased by 17% compared to the germination percentage (73%) of no coating treatment (CK). Root growth was also significantly increased by coating with M-Embed. Chlorophyll, peroxidase, superoxide dismutase, catalase, proline, hydrogen peroxide and malondialdehyde levels indicated that the M-Embed had the best positive effects under salt stress conditions. Discussion: Therefore, embedding microorganisms in suitable capsule materials provides effective protection for the survival of the microorganism and this seed coating can alleviate salt stress in wheat. This process will benefit the development of sustainable agriculture in coastal regions with saline soils.
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To investigate the neuroprotection of recombinant human erythropoietin (rhEPO) against hypoxic/ischemic (HI) insult in three-day-old rats. Postnatal day 3 (PD3) rats were randomly divided into three groups: Sham group, HI group and HI+rhEPO group. Ligation of the right common carotid artery and hypoxia to induce HI brain injury. After HI insult, the rats received intraperitoneal injection of rhEPO (5000â IU/Kg, qod) in HI+rhEPO group or equal saline in other groups. On PD10, damage of brain tissue was examined by hematoxylin-eosin (HE) staining, observation of neuronal apoptosis in the hippocampus and cortex using immunofluorescence assay (marker: TUNEL). Immunohistochemical staining or western blotting was performed to detect the expression of cyclooxygenase-2 (COX-2), Caspase-3 and phosphorylated Akt (p-Akt) protein. On PD28, cognitive ability of rats was assessed by Morris water maze test. HI injury causes brain pathological morphology and cognitive function damage in PD3 rats, which can be alleviated by rhEPO intervention. Compared with the HI group, the HI+rhEPO group showed an increase in platform discovery rate and cross platform frequency, while the search platform time was shortened (Pâ <â 0.05). The proportion of TUNEL positive neurons and the expression of COX-2 and Caspase-3 proteins in brain tissue in the hippocampus and cortex was decreased, while the expression of p-Akt protein was upregulated (Pâ <â 0.05). RhEPO could protect against the pathological and cognitive impairment of immature brain induced by HI insult. This neuroprotective activity may involve in inhibiting inflammatory and apoptosis by activation of PI3K/Akt signaling pathway.
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Eritropoetina , Hipóxia-Isquemia Encefálica , Fármacos Neuroprotetores , Humanos , Ratos , Animais , Caspase 3/metabolismo , Ratos Sprague-Dawley , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ciclo-Oxigenase 2/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Encéfalo/metabolismo , Hipóxia/metabolismo , Hipóxia-Isquemia Encefálica/complicações , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/metabolismo , Eritropoetina/farmacologia , Eritropoetina/uso terapêutico , Isquemia/metabolismo , Animais Recém-Nascidos , Fármacos Neuroprotetores/farmacologiaRESUMO
To prepare a novel cassava starch-based phosphorus releasing super-absorbent polymer (CST-PRP-SAP), the single factor and orthogonal experiment were applied to analyze the effects of different reaction conditions on the absorption and phosphorus release capacities of CST-PRP-SAP samples. The structural and morphological characteristics of the cassava starch (CST), powdered rock phosphate (PRP), cassava starch-based super-absorbent polymer (CST-SAP) and CST-PRP-SAP samples were all compared with various technologies, such as the Fourier transform infrared spectroscopy and X-ray diffraction pattern, etc. The results showed that the CST-PRP-SAP samples had good performances of water retention and phosphorus release which were synthesized, such as the reaction temperature, starch content, P2O5 content, crosslinking agent, initiator, neutralization degree, and acrylamide content, which were 60 °C, 20% w/w, 10% w/w, 0.02% w/w, 0.6% w/w, 70% w/w, and 15% w/w, respectively. The water absorbency of CST-PRP-SAP was almost larger than that of the CST-SAP sample with a P2O5 content of 5.0% and 7.5%, and they all gradually decreased after three consecutive water absorption cycles. The CST-PRP-SAP sample could maintain about 50% of the initial water content after 24 h, even at the temperature of 40 °C. The swelling process of CST-PRP-SAP conformed to the non-Fickian diffusion, which was determined by the diffusion of water molecules and the relaxation process of polymer chain segments. The cumulative phosphorus release amount and release rate of the CST-PRP-SAP samples were increased with the increasing PRP content and the decreasing neutralization degree. After a 216 h immersion, the cumulative phosphorus release amount and release rate of the CST-PRP-SAP samples with different PRP contents were increased by 17.4 and 3.7 times, respectively. The rough surface of the CST-PRP-SAP sample after swelling was beneficial to the performance of water absorption and phosphorus release. The crystallization degree of PRP in the CST-PRP-SAP system was decreased and most of the PRP existed in the form of physical filling, and the available phosphorus content was increased to a certain extent. It was concluded that the CST-PRP-SAP synthesized in this study has excellent properties of continuous water absorption and retention with functions of promotion and the slow-release phosphorus.
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Cellobiose is the primary product of cellulose hydrolysis and is expected to function as a type of pathogen/damage-associated molecular pattern in evoking plant innate immunity. In this study, cellobiose was demonstrated to be a positive regulator in the immune response of lettuce, but halted autoimmunity when lettuce was exposed to concentrations of cellobiose >60 mg l-1. When lettuce plants were infected by Botrytis cinerea, cellobiose endowed plants with enhanced pre-invasion resistance by activating high ß-1,3-glucanase and antioxidative enzyme activities at the initial stage of pathogen infection. Cellobiose-activated core regulatory factors such as EDS1, PTI6, and WRKY70, as well as salicylic acid signaling, played an indispensable role in modulating plant growth-defense trade-offs. Transcriptomics data further suggested that the cellobiose-activated plant-pathogen pathways are involved in microbe/pathogen-associated molecular pattern-triggered immune responses. Genes encoding receptor-like kinases, transcription factors, and redox homeostasis, phytohormone signal transduction, and pathogenesis-related proteins were also up- or down-regulated by cellobiose. Taken together, the findings of this study demonstrated that cellobiose serves as an elicitor to directly activate disease-resistance-related cellular functions. In addition, multiple genes have been identified as potential modulators of the cellobiose-induced immune response, which could aid understanding of underlying molecular events.
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Arabidopsis , Arabidopsis/genética , Lactuca/genética , Celobiose/metabolismo , Resistência à Doença/genética , Botrytis/fisiologia , Doenças das Plantas , Regulação da Expressão Gênica de PlantasRESUMO
Microwave-assisted hydrolysis has been widely studied for cellulose fiber isolation, but the influence of reaction conditions and the microwave non-thermal effect are not well clarified. In this study, a series of well-designed experiments were carried out to measure the effects of reaction conditions including temperature, duration and alkali concentration. Compared to the other parameters, temperature was more relevant to the cellulose content in fiber. It could reach the maximum purity of 90.66 % when the temperature was up to 140 °C. Moreover, the existence of non-thermal effect of microwave has been confirmed through extensive determination and characterization of the fibers obtained from parallel controlled experiments conducted with or without microwave assistance. Approximately 50 %-75 % reduction in reaction time or 67 % of that in chemical costs would be realized under microwave with respect to traditional heating hydrolysis. Therefore, this work provides both deep insight and efficiency strategy into the microwave-assisted cellulose isolation.
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Rituximab is popularly used in the treatment of B-cell lymphomas that bear CD20 antigen. Most of the adverse events (AEs) induced by rituximab are infusion-related symptoms. However, rituximab-induced acute thrombocytopenia (RIAT), which often develops within the 1-3 days after rituximab administration, is relatively unusual, severe, and usually self-recovering. Until now, most of the reports about RIAT were described as case reports and RIAT often occurred in patients with mantle cell lymphoma (MCL). Here, we report two patients who developed severe RIAT, one patient had a refractory and relapsed follicular lymphoma (FL), and the other patient was newly diagnosed with splenic marginal zone lymphoma (SMZL). RIAT is a rare, under-diagnosed but serious adverse event that should arouse attention to clinicians, and routine blood count monitoring should be considered after the administration of rituximab, especially for high-risk lymphoma patients or patient with splenomegaly.
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Linfoma de Células B/complicações , Linfoma de Células B/tratamento farmacológico , Rituximab/efeitos adversos , Esplenomegalia/complicações , Esplenomegalia/tratamento farmacológico , Trombocitopenia/induzido quimicamente , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
Mitochondrial respiratory chain complex I deficiency is one of common mitochondrial disorders. However, the information is relatively little about the features of Chinese patients. In this study, the clinical, biological, and genetic analyses were performed in the children with respiratory chain complex I deficiency, in order to further understand the characteristics of the disease.Over a 3-year period, 67 patients (37 boys, 30 girls), presenting with unexplained multisystemic symptoms and signs were recruited. Clinical and laboratory data of the patients were summarized. Spectrophotometric assay was used for the analysis of mitochondrial complex I-V enzyme activity in peripheral leukocytes. The entire mitochondrial DNA (mtDNA) sequence was analysed for patients and their mothers.The children with respiratory chain complex I deficiency presented with multisystem dysfunction. Onset occurred before the third year of life in 96.9% patients without mtDNA mutation. Onset occurred before the third year of life in 76.5% of patients with mtDNA mutation (Pâ=â.03). About 51.5% of patients without mtDNA mutation had weakness, which is higher than 24% patients with mtDNA mutation (Pâ=â.02). Isolated complex I deficiency and combined complex I deficiency were found in 45 and 22 patients, respectively. The prevalence of isolated complex I deficiency was higher in the patients with mtDNA mutations (79.4%) than in the patients without mtDNA mutations (54.5%).Patients with nuclear DNA mutations are more likely to develop early onset in mitochondrial respiratory chain complex I deficiency. The patients with complex I deficiency of peripheral leukocytes may be more likely to be caused by mtDNA mutation.
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DNA Mitocondrial/genética , Complexo I de Transporte de Elétrons/deficiência , Doenças Mitocondriais/genética , Adolescente , Povo Asiático/genética , Criança , Pré-Escolar , China , Feminino , Humanos , Lactente , Masculino , MutaçãoRESUMO
INTRODUCTION: RNASET2 mutation has been reported in patients with cystic leukoencephalopathy without megalencephaly and the Aicardi-Goutieres syndrome. Both disorders are Mendelian mimics of congenital cytomegalovirus infection with overlapping features, including leukoencephalopathy, white matter alterations, intracranial calcification, delayed psychomotor development, intelligence disability and seizures. Only eight families with RNASET2 mutation have been previously reported. METHODS: Whole exome sequencing was performed and copy number variants were described by read-depth strategy. RESULTS: We identified a novel nonsense variant c.128G>A (p. W43*) and a 430 Kb 6q27 microdeletion encompassing RNASET2. Our patient did not show anterior temporal lobe subcortical cysts, hearing loss, dystonia or extra-neurological features. CONCLUSION: Our results provided further genetic and phenotypic information of RNASET2 mutation in Chinese patients and highlighted the importance for physicians to consider RNASET2-related disorders when diagnosing patients with congenital brain infection-like phenotypes.
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Deficiências do Desenvolvimento/genética , Ribonucleases/genética , Proteínas Supressoras de Tumor/genética , Povo Asiático/genética , Pré-Escolar , Deficiências do Desenvolvimento/patologia , Feminino , Genótipo , Humanos , Mutação , FenótipoRESUMO
Tbx3, a member of the T-box family of transcription factors, contributes directly to tumor formation, migration, and invasion. However, the role of Tbx3 in the metastasis of HCC remains unclear. In the present study, Tbx3 expression was detected in HCC tissues and cells by Western blot, and Tbx3 expression was regulated by use of siRNAs or lentivirus-mediated vectors. Here we found that Tbx3 protein expression increased in HCC tissues and cell lines. Tbx3 expression was positively associated with multiple tumor nodes, venous infiltration, and advanced TNM tumor stage. Survival analysis demonstrated that Tbx3 expression was an independent prognostic factor for HCC patients. In vitro assays further validated that Tbx3 indeed prompted HCC cell migration and invasion. In addition, Tbx3 expression was negatively related with E-cadherin expression in HCC tissues. Mechanically, Tbx3 inhibited the expression of E-cadherin, and then facilitated epithelial-mesenchymal transition (EMT) of HCC cells. Furthermore, the effect of Tbx3 knockdown on HCC cells was attenuated by E-cadherin knockdown. In conclusion, Tbx3 may be a novel prognostic factor, and it contributes to HCC cell migration, invasion, and EMT by repressing E-cadherin expression. Thus, Tbx3 may be recommended as a therapeutic target for HCC patients.
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Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Caderinas/metabolismo , Carcinoma Hepatocelular/patologia , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , Proteínas com Domínio T/metabolismo , Antígenos CD/genética , Apoptose , Biomarcadores Tumorais/genética , Caderinas/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proliferação de Células , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Invasividade Neoplásica , Prognóstico , Taxa de Sobrevida , Proteínas com Domínio T/genética , Células Tumorais CultivadasRESUMO
Acanthospermum hispidum DC, an Asteraceae weed species, was very susceptible to fluazifop-P-butyl, but tolerant to other aryloxyphenoxypropionate herbicides, such as haloxyfop-P-methyl. However, other Asteraceae weeds including Bidens pilosa were all tolerant to fluazifop-P-butyl. Membrane lipid peroxidation by increasing the levels of reactive oxygen species (ROS) was proposed as an action mechanism of fluazifop-P-butyl in A. hispidum. To further clarify the primordial action site of fluazifop-P-butyl in this species, the effects on chlorophyll fluorescence characteristics and cytohistology of apical meristems were studied. Chlorophyll fluorescence characteristics (CFC) in sensitive A. hispidum seedlings were markedly affected by 10µM fluazifop-P-butyl, with the dark fluorescence yield (Fo), maximal fluorescence yield (Fm), maximal PS II quantum yield (Fv/Fm), effective photosystem II (PS II) quantum yield [Y(II)], and quantum yield of regulated energy dissipation [Y(NPQ)] declining, quantum yield of nonregulated energy dissipation [Y(NO)] rising, but these measures were not affected in Bidens pilosa. The effects of fluazifop-P-butyl on chlorophyll fluorescence properties were observed on the growing point before the mature leaves by about 4-6h. Haloxyfop-P-methyl, a control herbicide, had no effects on CFC of either A. hispidum or B. pilosa. In addition, damage to apical meristem cells of A. hispidum was observed at 6 HAT prior to changes in chlorophyll fluorescence parameters suggesting that the primary action site of fluazifop-P-butyl in this species is in the apical meristem and the effects on CFC may be the results of secondary action.
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Asteraceae/efeitos dos fármacos , Herbicidas/farmacologia , Piridinas/farmacologia , Asteraceae/química , Asteraceae/genética , Asteraceae/metabolismo , Clorofila/química , Clorofila/metabolismo , Fluorescência , Plantas Daninhas/química , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/genética , Plantas Daninhas/metabolismo , Plântula/química , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/metabolismoRESUMO
MicroRNAs (miRNAs/miRs) are important molecules that are able to regulate multiple cellular processes in cancer cells. miR-7 has been previously identified as a tumor suppressive miRNA in several types of cancer. The aim of the present study was to investigate whether miR-7 is able to regulate autophagy in hepatocellular carcinoma (HCC) cells. It was identified that miR-7 was significantly downregulated in tumor tissues compared with adjacent normal tissues. Overexpression of miR-7 inhibited cell proliferative activity, which was partially reversed by miR-7 inhibitor. In addition, overexpression of miR-7 significantly induced an increasen in autophagic activity, and luciferase activity assay and western blot analysis identified that mammalian target of rapamycin (mTOR) was a direct target of miR-7. In addition, inhibition of autophagy by 3-methyladenine resulted in a marked enhancement of the proliferation inhibition effect of miR-7. In conclusion, miR-7 was identified to induce proliferation inhibition and autophagy in HCC cells by targeting mTOR, and inhibition of autophagy may be utilized to enhance the antitumor activity of miR-7.
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A soil remediation method based on magnetic beneficiation is reported. A new magnetic solid chelator powder, FS@IDA (core-shell Fe3O4@SiO2 nanoparticles coated with iminodiacetic acid chelators), was used as a reactive magnetic carrier to selectively capture non-magnetic heavy metals in soil by chelation and removal by magnetic separation. FS@IDA was prepared via inorganic-organic and organic synthesis reactions that generated chelating groups on the surface of magnetic, multi-core, core-shell Fe3O4@SiO2 (FS) nanoparticles. These reactions used a silane coupling agent and sodium chloroacetate. The results show that FS@IDA could chelate the heavy metal component of Cd, Zn, Pb, Cu and Ni carbonates, lead sulfate and lead chloride in water-insoluble salt systems. The resulting FS@IDA-Cd and FS@IDA-Pb chelates could be magnetically separated, resulting in removal rates of approximately 84.9% and 72.2% for Cd and Pb, respectively. FS@IDA could not remove the residual heavy metals and those bound to organic matter in the soil. FS@IDA did not significantly alter the chemical composition of the soil, and it allowed for fast chelating capture, simple magnetic separation and facilitated heavy metal elution. FS@IDA could also be easily prepared and reprocessed.
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Quelantes/química , Nanopartículas de Magnetita/química , Metais Pesados/química , Poluentes do Solo/química , Solo/química , Adsorção , Cádmio/química , Cátions , Concentração de Íons de Hidrogênio , Chumbo/química , SolubilidadeRESUMO
BACKGROUND: Previous studies have suggested a possible association between hyperuricemia and nonalcoholic fatty liver disease (NAFLD), but the risk of NAFLD in individuals with hyperuricemia had not been fully quantified. A systematic review and meta-analysis of relevant studies was carried out to estimate the influence of hyperuricemia on the risk of NAFLD. METHODS: PubMed, Embase, Web of Science, and Wanfang databases were searched for cohort or cross-sectional studies assessing the association between hyperuricemia and NAFLD. Relative risks (RRs) with 95% confidence intervals (95% CIs) were pooled using a random-effects model to estimate the impact of hyperuricemia on the risk of NAFLD. RESULTS: Thirteen studies from 12 articles were finally included in the meta-analysis. There were a total of 117,712 participants and 28,446 (24.2%) NAFLD cases. Individuals with hyperuricemia had an obviously increased risk of NAFLD compared with those without hyperuricemia (RR=1.79, 95% CI 1.55-2.07, P<0.001). Increased risk of NAFLD was obviously associated with hyperuricemia in both men (RR=1.26, 95% CI 1.15-1.37, P<0.001) and women (RR=2.01, 95% CI 1.58-2.56, P<0.001). Subgroup analyses further identified the robustness of the association between hyperuricemia and NAFLD. CONCLUSION: Hyperuricemia is associated with an increased risk of NAFLD in Asian populations. Further prospective cohort studies are needed to assess the impact of hyperuricemia on the risk of NAFLD in Western countries.
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Hiperuricemia/epidemiologia , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Biomarcadores/sangue , Feminino , Humanos , Hiperuricemia/sangue , Hiperuricemia/diagnóstico , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Razão de Chances , Prevalência , Medição de Risco , Fatores de Risco , Fatores Sexuais , Ácido Úrico/sangueRESUMO
At field scale, surface soil had special characteristics of volumetric moisture content (VMC) with a relatively little difference and spatial heterogeneity induced by physical and chemical properties, roughness, straw residues, etc. It has been a great challenge for near infrared diffuse reflectance spectroscopy (NIR-DRS) measurement of surface soil moisture in situ. In this study, exonential decay models based on seven water-related wavelengths (1200, 1400, 1450, 1820, 1940, 2000 and 2250 nm), linear models of normalized difference soil moisture index (NSMI) and relative absorption depth (RAD) based on wave-length combinations, linear or quadratic model of width of the inflection (σ), center amplitude of the function (Rd) and area under the Gaussian curve (A) from soil moisture Gaussian model (SMGM), and partial least square (PLS) regression models based on bands were used to quantify VMC. The results indicated that (1) of all the single wavelengths, 2 000 nm showed the best validation result, indicated by the lowest RMSEp (2.463) and the highest RPD value (1.060). (2) Comparing with RAD, the validation of NSMI was satisfactory with higher R² (0.312), lower RMSEp (2.133) and higher RPD value (1.224). (3) In the validation results of SMGM parameters and PLS fitting, Rd was found to produce the best fitting quality identified by the highest R² (0.253), the lowest RMSEp (2.222), and the highest RPD value (1.175). (4) Comprehensively, a linear model based on NSMI showed the highest validation accuracy of all the methods. What is more, its calculation process is simple and easy to operate, and therefore become the preferred method to quantify surface soil moisture content in situ.
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In the present study, late frost experiments were implemented under a range of subfreezing temperatures (-1 - -9 degrees C) by using a field movable climate chamber (FMCC) and a cold climate chamber, respectively. Based on the spectra of winter wheat canopy measured at noon on the first day after the frost experiments, red edge parameters REP, Dr, SDr, Dr(min), Dr/Dr(min) and Dr/SDr were extracted using maximum first derivative spectrum method (FD), linear four-point interpolation method (FPI), polynomial fitting method (POLY), inverted Gaussian fitting method (IG) and linear extrapolation technique (LE), respectively. The capacity of the red edge parameters to detect late frost stress was explicated from the aspects of the early, sensitivity and stability through correlation analysis, linear regression modeling and fluctuation analysis. The result indicates that except for REP calculated from FPI and IG method in Experiment 1, REP from the other methods was correlated with frost temperatures (P < 0.05). Thereinto, significant levels (P) of POLY and LE methods all reached 0.01. Except for POLY method in Experiment 2, Dr/SDr from the other methods were all significantly correlated with frost temperatures (P < 0.01). REP showed a trend to shift to short-wave band with decreasing temperatures. The lower the temperature, the more obvious the trend is. Of all the REP, REP calculated by LE method had the highest correlation with frost temperatures which indicated that LE method is the best for REP extraction. In Experiment 1 and 2, only Dr(min) and Dr/Dr(min), calculated by FD method simultaneously achieved the requirements for the early (their correlations with frost temperatures showed a significant level P < 0.01), sensitivity (abso- lute value of the slope of fluctuation coefficient is greater than 2.0) and stability (their correlations with frost temperatures al- ways keep a consistent direction). Dr/SDr calculated from FD and IG methods always had a low sensitivity in Experiment 2. In Experiment 1, the sensitivity of Dr/SDr from FD was moderate and IG was high. REP calculated from LE method had a lowest sensitivity in the two experiments. Totally, Dr(min) and Dr/Dr(min) calculated by FD method have the strongest detection capacity for frost temperature, which will be helpful to conducting the research on early diagnosis of late frost injury to winter wheat.
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Temperatura Baixa , Triticum , Clima , Análise Espectral , Estresse FisiológicoRESUMO
A field experiment was conducted to study the effects of foliar spraying of three kinds of compound agents [plant polysaccharides (P1), plant polysaccharides plus 5-aminolevulinic acid (P2), and plant polysaccharides plus 5-aminolevulinic acid and dimethylpiperidinium chloride (P3)] at the initial flowering stage of winter wheat on its yield components, sucrose content, soluble sugar content, the accumulation and translocation of dry matter, nitrogen and phosphorus. The grain number per spike and kilo-grains mass of winter wheat increased with the spray of the compound agents. The grain yield increased by more than 8.5% compared with the control. Within 20 days after spraying the three compound agents, the sucrose content of flag leaf had an obvious increase. Compared with the control, P1 and P3 increased the soluble sugar content by more than 4.5% and 11.0%, respectively. P3 enhanced the accumulations of post-anthesis dry matter, nitrogen and phosphorus by 48.5%, 116.9% and 18. 1%, respectively. Correspondingly, contributions of accumulated post-anthesis dry matter and nutrient to grain yield increased significantly. Whereas, the contribution of translocated pre-anthesis nutrient to grain yield in P3 treatment was smaller than in the other treatments. The high yield of winter wheat was related to the regulation of photosynthetic product supply in vegetative organ, the increased soluble sugar content in grain, and the accumulation of post-anthesis dry matter and nutrient regulated by the plant polysaccharides-containing compound agent.
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Ácido Aminolevulínico/química , Polissacarídeos/química , Triticum/química , Biomassa , Nitrogênio/química , Fósforo/química , Fotossíntese , Folhas de Planta , Estações do AnoRESUMO
OBJECTIVES: To prospectively evaluate the feasibility, safety and accuracy of magnetic resonance imaging (MRI)-guided percutaneous coaxial cutting needle biopsy of small (≤2.0 cm in diameter) pulmonary nodules. METHODS: Ninety-six patients (56 men and 40 women) with 96 small lung nodules underwent MRI-guided percutaneous coaxial cutting needle biopsy. These lesions were divided into two groups according to maximum nodule diameters: 0.5-1.0 cm (n = 25) and 1.1-2.0 cm (n = 71). The diagnostic accuracy, sensitivity and specificity were calculated, and comparison of the two groups was performed using Fisher's exact test. RESULTS: All specimens obtained were sufficient for diagnosis. Histological examination of needle biopsy revealed 64 malignant, 30 benign and 2 indeterminate nodules. The final diagnoses from surgery or clinical follow-up were 67 malignant nodules and 29 benign nodules. The diagnostic performance of MRI-guided percutaneous coaxial cutting needle biopsy in diagnosing malignant tumours was as follows: accuracy, 97 %; sensitivity, 96 %; specificity, 100 %; positive predictive value, 100 %; and negative predictive value, 91 %. There was no significant difference between the two groups (P > 0.05, Fisher's exact test). No serious complications occurred. CONCLUSIONS: MRI-guided percutaneous coaxial cutting needle biopsy is a safe and accurate diagnostic technique in the evaluation of small lung nodules. KEY POINTS: ⢠MRI-guided biopsy helps clinicians to assess patients with small lung nodules. ⢠Differentiation of malignant and benign nodules is possible with 97 % accuracy. ⢠MRI guidance enables accurate lung biopsy without ionising radiation. ⢠No serious complications occurred in MRI-guided lung biopsy.
Assuntos
Biópsia Guiada por Imagem/métodos , Neoplasias Pulmonares/patologia , Imageamento por Ressonância Magnética/métodos , Nódulos Pulmonares Múltiplos/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto JovemRESUMO
A field experiment was conducted to study the effects of foliar spraying three compound agents [plant polysaccharides (P1), plant polysaccharides and 5-aminolevulinic acid (P2), and plant polysaccharides and 5-aminolevulinic acid and dimethylpiperidinium chloride (P3)] at the initial flowering stage of soybean on its leaf chlorophyll content, photosynthesis and transpiration, dry matter accumulation and allocation, and grain yield. Within 35 days after spraying the three compound agents, the leaf chlorophyll content had obvious increase, and its decreasing trend with plant growth had somewhat delay. Compared with the control, spraying P1 and P3 increased the leaf photosynthetic rate and water use efficiency by more than 13.2% and 10.3%, respectively. With the spraying of the three compound agents, the dry matter accumulation in aerial part increased, and the allocation of dry matter from leaf to pod was also enhanced, with the contribution of post-anthesis assimilates to grain yield increased by more than 17.1%. The 100-grain mass and the pods and seeds per plant increased significantly after spraying P1 and P3, but had no significant increase after spraying P2. The grain yield of soybean treated with the three compound agents increased by more than 5.9%, compared with the control. This study showed that the three plant polysaccharide compound agents could increase the leaf chlorophyll content, delay the leaf-senescence, improve the leaf photosynthetic capacity and water status, effectively control the dry matter accumulation and post-anthesis assimilates allocation, and increase the grain yield of soybean.