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Objectives: This current study is based on a set of visual motion sensitivity tests, investigating the correlation between visual motion sensitivity and diabetic retinopathy (DR) in type 2 diabetes mellitus (T2DM), thereby furnishing a scientific rationale for preventing and controlling DR. Methods: This research was conducted by a combination of questionnaire collection and on-site investigation that involved 542 T2DM recruited from a community. The visual motion sensitivity determined the visual motion perception of the participants across three spatial frequencies (low, medium, and high) for both the first- and second-order contrast. The logistic regression model was adopted to investigate the relationship between visual motion sensitivity and DR prevalence. Besides, the Pearson correlation analysis was used to analyze the factors influencing visual motion sensitivity and restricted cubic spline (RCS) functions to assess the dose-response relationship between visual motion sensitivity and glycated hemoglobin. Results: Among 542 subjects, there are 162 cases of DR, with a prevalence rate of 29.89%. After adjusting factors of age, gender, glycated hemoglobin, duration of diabetes, BMI, and hypertension, we found that the decline in first- and second-order high spatial frequency sensitivity increased the risk for DR [odds ratio (OR): 1.519 (1.065, 2.168), 1.249 (1.068, 1.460)]. The decline in perceptual ability of second-order low, medium, and high spatial frequency sensitivity is a risk factor for moderate to severe DR [OR: 1.556 (1.116, 2.168), 1.388 (1.066, 1.806), 1.476 (1.139, 1.912)]. The first-order and the second-order high spatial frequency sensitivity are significantly positively correlated with glycated hemoglobin (r = 0.105, p = 0.015 and r = 0.119, p = 0.005, respectively). Conclusion: Visual motion sensitivity especially for the second-order high spatial frequency stimuli emerges as a significant predictor of DR in T2DM, offering a sensitive diagnostic tool for early detection.
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This study aimed to develop a novel fluorescent aptasensor for the quantitative detection of zearalenone (ZEN), addressing the limitations of conventional detection techniques in terms of speed, sensitivity, and ease of use. Nitrogen-doped carbon dots (N-CDs) were synthesized via the hydrothermal method, resulting in spherical particles with a diameter of 3.25 nm. These N-CDs demonstrated high water solubility and emitted a bright blue light at 440 nm when excited at 355 nm. The fluorescence of N-CDs was quenched by dispersed gold nanoparticles (AuNPs) through the inner filter effect, while aggregated AuNPs induced by NaCl did not affect the fluorescence of N-CDs. The aptamer could protect AuNPs from NaCl-induced aggregation, but the presence of ZEN weakened this protective effect. Based on this principle, optimal conditions for ZEN detection included 57 mM NaCl, 12.5 nM aptamer concentration, incubation of AuNPs with NaCl for 15 min in Tris-EDTA(TE) buffer, and incubation of aptamer with ZEN and NaCl for 30 min. Under these optimized conditions, the "signal-on" fluorescent aptasensor for ZEN detection showed a linear range of 0.25 to 200 ng/mL with a low detection limit of 0.0875 ng/mL. Furthermore, the developed aptasensor exhibited excellent specificity and could rapidly detect ZEN in corn flour samples or corn oil, achieving satisfactory recovery rates ranging from 84.7% to 108.6%. Therefore, this study presents an economical, convenient, sensitive, and rapid method for accurately quantifying ZEN in cereal products.
Assuntos
Técnicas Biossensoriais , Carbono , Grão Comestível , Ouro , Nanopartículas Metálicas , Nitrogênio , Zearalenona , Carbono/química , Grão Comestível/química , Nitrogênio/química , Nanopartículas Metálicas/química , Ouro/química , Zearalenona/análise , Aptâmeros de Nucleotídeos/química , Limite de Detecção , Pontos Quânticos/química , FluorescênciaRESUMO
Objective: Visceral adipose tissue assessment holds significant importance in hypertension prevention. This study aimed to explore the association between the Metabolic Score for Visceral Fat (METS-VF), a new indicator based on laboratory and anthropometry measures, and hypertension risk and to further investigate the association between the METS-VF and the risk of hypertension in different ethnic groups. Methods: In this study, a total of 9,280 people from 48 townships in 12 districts (counties) of Guizhou Province were selected for the survey using a multistage cluster random sampling method, and 5,127 cases were finally included in the analysis after excluding those with missing relevant data, losing visits, dying at follow-up, those who suffered from hypertension at baseline, and those whose information on the outcome of hypertension was not clear. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) between METS-VF and incident hypertension, and an accelerated failure time (AFT) model was applied to analyze the association between METS-VF and the onset time of hypertension. Results: The total person-years (PYs) of the 5,127 subjects were 36,188.52 years, and the median follow-up time was 6.64 years. During follow-up, 1,127 patients were newly diagnosed with hypertension, and the incidence density was 31.14/1,000 PYs. After adjusting for multivariables, compared with the METS-VF first (Q1), the third (Q3) and fourth (Q4) groups of the METS-VF increased by 29.9% and 61.5%, respectively (HR = 1.299 [1.061, 1.590] and 1.615 [1.280, 2.036]). The risk of hypertension increased with higher METS-VF values (HR = 1.323 [1.167, 1.500], ptrend < 0.001). In the Han Chinese population, Q2 and Q3 increased the risk of hypertension (HR = 1.459 [1.111, 1.917], 1.999 [1.417, 2.718]), and the onset of hypertension was advanced by 0.653 (ß = -0.653 (-0.930, -0.375]) years for per 1 unit increase in METS-VF. However, these associations were not found in ethnic minorities. Conclusion: METS-VF was significantly positively associated with the risk of hypertension, and the association was different among ethnic groups.
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Hipertensão , Síndrome Metabólica , Humanos , Gordura Intra-Abdominal , Síndrome Metabólica/epidemiologia , Etnicidade , Estudos Prospectivos , Hipertensão/complicaçõesRESUMO
There is an urgent need to develop an economical and convenient method for the ultrasensitive detection of patulin (PAT), a mycotoxin that can potentially harm human health when it is found in fruits and their derivatives. In this study, we have developed a novel fluorescent aptasensor that utilizes nitrogen-doped carbon dots (N-CDs) as the fluorescent donor and hexagonal ß-Co(OH)2 nanoplates as the fluorescent acceptor. N-CDs were synthesized through the hydrothermal method, resulting in spherical particles with a diameter of 7.6 nm. These nanoparticles exhibited excellent water solubility and displayed a vibrant blue emission at 448 nm when excited at 360 nm. Cobalt hydroxide nanoplates with a beta crystal structure [ß-Co(OH)2] were synthesized using a simple co-precipitation method, exhibiting hexagonal plate-like shapes with uniform lateral sizes of 4-5 µm. The fluorescence of N-CDs can be efficiently quenched by hexagonal ß-Co(OH)2 nanoplates through Förster resonance energy transfer mechanism. The maximum quenching-recovery capability can be achieved when the concentrations of N-CDs-Apt and ß-Co(OH)2 nanoplates are 150 nmol/L and 100 µg/mL, respectively. The pH of the TE buffer should be 8.0, and the incubation time should be 10 min at 25 °C. The developed fluorescent aptasensor displayed an excellent selectivity for PAT determination with a detection limit of 0.57 pg/mL in the linear range of 1.25 pg/mL-100 ng/mL. The rapid PAT determination in fruit juice samples was realized with good recoveries (96.9-105.8%). The developed fluorescent aptasensor based on the interaction between N-CDs and hexagonal ß-Co(OH)2 nanoplates can be a promising method for the rapid and ultrasensitive detection of PAT in agricultural products.
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Patulina , Humanos , Agricultura , Carbono , Corantes , NitrogênioRESUMO
The widespread of patulin (PAT) and its potential hazards to human health call for alternative rapid assays to monitor it in food and the environment. Herein, we prepared chromium hydroxide [Cr(OH)3] nanoparticles via a one-pot chemical precipitation strategy and used them to fabricate a turn-on fluorescent aptasensor employing a morphological effect for sensitive PAT detection. Three Cr(OH)3 nanoparticle structures were synthesized by changing the solvent, and their structures and physicochemical properties were investigated. Then, we evaluated the effects of morphological structures on the fluorescence quenching-recovery capability of Cr(OH)3 nanoparticles before and after incubation with PAT. We found that the Cr(OH)3-3 nanoparticles efficiently absorbed the fluorescence dye 6-carboxyfluorescein labeled aptamer (FAM-Apt) and quenched the fluorophore through photoinduced electron transfer. Under optimal experimental conditions, the turn-on fluorescent aptasensor for PAT determination displayed two linear ranges (0.01-10 ng/mL and 1-200 ng/mL) with a low detection limit of 7.3 pg/mL. Moreover, the proposed aptasensor had no cross-reactivity with interferents that usually coexist with PAT and can be used to detect PAT in apple juices accurately. The results of the as-fabricated method were not significantly different from the high-performance liquid chromatography. Hence, we demonstrated that different Cr(OH)3 nanoparticles can be prepared by changing reaction conditions, and provided a novel strategy to improve the detection performance of fluorescent aptasensor by changing the morphological structure and crystalline properties of nano-quenchers.
Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas , Patulina , Humanos , Patulina/análise , Cromo , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Limite de DetecçãoRESUMO
PURPOSE: To compare the recurrence rate and surgical complications of retinopathy of prematurity (ROP) between patients treated with intravitreal injection of conbercept (IVC) and intravitreal injection of ranibizumab (IVR) within 6 months. METHODS: A multicentral prospective, randomised controlled trial was applied from May 2017 to February 2019 for the infants diagnosed as aggressive posterior-ROP, zone I or posterior zone II treatment-requiring ROP by binocular indirect ophthalmoscope and RetCam3. These infants were assigned to randomly receive either intravitreal injection of 0.25 mg conbercept or 0.25 mg ranibizumab. The recurrence rate, fundus fluorescence angiography (FFA) and surgical complications were examined during the follow-up period of 6 months. Recurrent eyes were retreated by laser or another intravitreal injection within the 72 hours. RESULTS: A total of 30 infant patients (60 eyes) underwent IVC and 30 patients (60 eyes) underwent IVR. A total of 10 eyes (16.67%) in the IVC group and 14 eyes (23.34%) in the IVR group developed recurrence. There was no significant statistical difference in the recurrence rate between the two groups (χ2=0.83, p=0.36). The postmenstrual age (PMA) at first injection was (34.60±3.47) weeks in IVC and (35.14±1.76) in IVR group. In recurrent cases, the mean PMA at second treatment were (43.31±3.85) and (43.43±3.89) weeks in the IVC and IVR group, respectively. The period between two treatments was (8.71±6.62) for the IVC and (8.29±2.56) weeks for the IVR group. All these results showed no significant statistical difference between these two groups. The fluorescein leakage were observed in the eyes of recurrent infants by FFA. There were no other complications in the two groups except for complicated cataract in three eyes. CONCLUSION: Both IVC and IVR are effective therapies for the treatment of ROP. Conbercept is a new option for treating ROP.
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Ranibizumab , Retinopatia da Prematuridade , Inibidores da Angiogênese/uso terapêutico , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Injeções Intravítreas , Estudos Prospectivos , Ranibizumab/uso terapêutico , Proteínas Recombinantes de Fusão , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/tratamento farmacológico , Retinopatia da Prematuridade/cirurgia , Estudos RetrospectivosRESUMO
Lipoxygenases (Loxs) are dioxygenases that play an important role in plant growth and defense. Loxs affect flour processing quality in common wheat (Triticum aestivum). We conducted a genome-wide association study (GWAS) that identified 306 significant single-nucleotide polymorphisms (SNPs) related to Lox activity in Chinese wheat accessions. Among them, a novel lipoxygenase-encoding (Lpx) gene, TaLpx-B4, was detected on chromosome 3B in a biparental population. Analysis of mutant wheat lines induced using ethyl methanesulfonate confirmed the role of TaLpx-B4 in modulating Lox activity. A phylogenetic tree of various plant Lpx genes indicated the predominance of the 9-Lpx type in common wheat. Further analysis revealed conserved intron number, exon length, and motif number in the TaLpx gene family. GWAS, linkage mapping, and gene annotation collectively showed that 14 out of 29 annotated TaLpx genes played a critical role in regulating Lox activity in the Chinese wheat accessions. Transgenic wheat grains with knockdown of Lpx family genes by RNAi showed significantly lower Lox activity than the wild type. One TaLpx-RNAi line had significantly reduced starch content and dough stability, and thus possessed relatively superior biscuit quality in soft wheat. Further analysis of the transcriptome, lipid components, and other metabolites revealed that knockdown of TaLpx genes significantly increased biscuit quality via changes in unsaturated fatty acid content as well as in starch, sucrose, and galactose metabolism. Our results provide new insights into the role of the TaLpx gene family that will be beneficial in improving soft wheat flour quality.
Assuntos
Farinha , Triticum , Estudo de Associação Genômica Ampla , Lipoxigenase/genética , Filogenia , Triticum/genéticaRESUMO
Purpose: To investigate the relationship between proangiogenic and inflammatory cytokines in concurrent vitreous, aqueous, and plasma samples from patients with proliferative diabetic retinopathy (PDR). Methods: Vitreous, aqueous, and plasma samples were analyzed using multiplex immunoassay for 10 PDR-related cytokines (IL-6, IL-8, TNF-α, monocyte chemoattractant protein-1 [MCP-1], macrophage inflammatory protein-1ß [MIP-1ß], VEGF receptor 1 [Flt-1], placental growth factor [PlGF], VEGF-A, VEGF-C, VEGF-D). A total of 17 patients with PDR and 7 controls were included. The primary outcome was correlation of cytokines in vitreous, aqueous, and plasma. The secondary outcome was the comparison of cytokine levels in controls and diabetics with and without recent anti-VEGF injection. Results: The following factors were elevated in diabetics compared with controls: vitreous IL-6, IL-8, TNF-α, MCP-1, MIP-1ß, PlGF, and VEGF-A; and aqueous IL-6, IL-8, PlGF, and VEGF-C (all P < 0.05). Vitreous and aqueous IL-8, PlGF, and VEGF-A were significantly correlated in patients with PDR (all P < 0.05). Plasma cytokines were not correlated with those in vitreous and aqueous (all P > 0.05). Vitreous and aqueous IL-6, IL-8, TNF-α, PlGF, and VEGF-A differed among controls and diabetics with and without recent anti-VEGF injection (all P < 0.05). In one-to-one comparisons, aqueous VEGF-A levels were lower in diabetic patients who had recent anti-VEGF injection compared with those who did not (P = 0.01). Conclusions: In this proof-of-concept study, IL-8, VEGF-A, and PlGF demonstrated a strong correlation in vitreous and aqueous of patients with PDR. The aqueous may serve as a proxy for vitreous for some cytokines involved in PDR. Recent anti-VEGF injections decreased VEGF-A levels in aqueous, but did not significantly affect other cytokines, suggesting a role for other targeted therapies in PDR management.
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Humor Aquoso/metabolismo , Citocinas/metabolismo , Retinopatia Diabética/metabolismo , Corpo Vítreo/metabolismo , Adulto , Idoso , Inibidores da Angiogênese/uso terapêutico , Estudos de Casos e Controles , Citocinas/sangue , Retinopatia Diabética/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
PURPOSE: To compare the foveal microvascular structure characteristics in children with a history of intravitreal injection of ranibizumab (IVR) versus laser photocoagulation (LP) for retinopathy of prematurity by optical coherence tomography angiography (OCTA). METHODS: In this cross-sectional study, a total of 17 children (28 eyes) underwent IVR and 20 children (37 eyes) underwent LP were recruited. The age of doing OCTA examination of the two groups are 5.4±1.1 years and 6.3±1.8 years, respectively (p=0.07). Spectral-domain OCTA was performed for all the eyes with a scan size of 3×3 mm. The data of the superficial retinal layer were analysed. The foveal avascular zone (FAZ) and vessel density (including vessel length density (VLD) and perfusion density (PD)) were measured using the software of OCTA (Cirrus AngioPlex 5000, Carl Zeiss, Meditec, Dubin, California, USA). The central foveal thicknesses (CFT) were measured by cross-sectional OCT. RESULTS: In the central fovea, the retinal VLD and PD of patients with IVR were 13.82±2.99 mm/mm2 and 0.25±0.05 mm2/mm2, respectively, which were significantly lower than those of the LP group (15.64±2.71 mm/mm2 and 0.28±0.05 mm2/mm2, p=0.01 and p=0.006). The FAZ area of patients with IVR and LP were 0.13±0.09 mm2 and 0.09±0.07 mm2, respectively (p=0.048). The CFT of patients with IVR and LP were 200.7±16.7 µm and 220.9±22.7 µm, respectively (p<0.01). The logarithm of the minimal angle of resolution best-corrected visual acuity of patients with IVR and LP were 0.2±0.1 and 0.1±0.1, respectively (p=0.01). There was no significant difference in the parafoveal and foveal VLD and PD, FAZ morphological index and spherical equivalent refraction (SER) between the two groups. CONCLUSION: The IVR might contribute to microvascular changes in the macular zone, such as reducing the central foveal VLD and PD, while the LP might contribute to microstructural changes, such as smaller FAZ and thicker CFT.
Assuntos
Inibidores da Angiogênese/uso terapêutico , Angiofluoresceinografia , Fotocoagulação a Laser , Ranibizumab/uso terapêutico , Retinopatia da Prematuridade/terapia , Tomografia de Coerência Óptica , Criança , Pré-Escolar , Estudos Transversais , Feminino , Seguimentos , Humanos , Injeções Intravítreas , Macula Lutea/irrigação sanguínea , Masculino , Refração Ocular/fisiologia , Vasos Retinianos/fisiopatologia , Retinopatia da Prematuridade/tratamento farmacológico , Retinopatia da Prematuridade/fisiopatologia , Retinopatia da Prematuridade/cirurgia , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologiaRESUMO
Changes of key odorants and aroma profiles of Chinese Laowuzeng baijiu during its one-year ageing were determined by HS-SPME-AEDA and direct injection-AEDA (DI-AEDA). Ethyl hexanoate, (E,E)-2,4-decadienal, and 2-phenylethyl acetate showed the highest FD value (486) in all ageing stages. With regards to aroma profiles, fruity, floral, acidic, sweet/honey and cheesy aromas were enhanced during storage, while pickled vegetable, grain and alcoholic notes weakened during the ageing. Quantitation and OAVs showed that most of the aroma compounds (OAVs > 1), including ethyl esters, aldehydes, and acids, increased their contents within the same period, whereas nonanal, 2-phenylethyl acetate, ethyl benzoate, 4-ethylguaiacol, propanol and 3-methyl-1-butanol decreased in content after the storage of 365 days. Simulated aged samples, in which fresh samples were spiked with 18 compounds, were examined by triangle tests, which indicated that the "fruity" compounds were crucial for maintaining the special aroma profile of an aged sample.
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Bebidas Alcoólicas/análise , Odorantes/análise , Acetatos/análise , Adulto , Aldeídos/análise , China , Feminino , Análise de Alimentos/métodos , Armazenamento de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pentanóis/análise , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/análise , Olfato , Microextração em Fase Sólida , Fatores de Tempo , Compostos Orgânicos Voláteis/análiseRESUMO
Volatile sulfur-containing compounds (VSCs) often exist at extremely low concentrations, making them difficult to be determined. The VSCs in Laobaigan (LBG) Baijiu were analyzed by headspace solid-phase microextraction (HS-SPME) coupled with GCâ¯×â¯GC-SCD, by which 12â¯VSCs were identified. Among the 65 odor-active compounds that were determined by GC-O with the aid of aroma extract dilution analysis (AEDA), benzenemethanethiol and 2-methyl-3-furanthiol were found to possess the highest FD values of 6561. The limits of detection (LODs) of the identified VSCs determined by GCâ¯×â¯GC-SCD were found to be extremely low at 0.05-1.53â¯ng/L, with their analytical recoveries from 85% to 116%. The VSCs in the LBG samples were determined in a range of concentrations from 0.77⯱â¯0.02⯵g/L to 60.04⯱â¯2.32⯵g/L. Benzenemethanethiol, dimethyl trisulfide, 2-methyl-3-furanthiol and 2-furfurylthiol exhibited odor activity values (OAVs)â¯>â¯100 and significantly contributed to the overall aroma of LBG Baijiu.
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Bebidas Alcoólicas/análise , Análise de Alimentos/métodos , Odorantes/análise , Enxofre/análise , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa/métodos , Furanos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limite de Detecção , Luminescência , Olfatometria/métodos , Microextração em Fase Sólida/métodos , Compostos de Sulfidrila/análise , Compostos de Enxofre/análise , Compostos Orgânicos Voláteis/químicaRESUMO
Flour colour, kernel hardness, grain protein content and wet gluten content are important quality properties that determine end use in bread wheat. Here, a wheat 90K genotyping assay was used for a genome-wide association study (GWAS) of the six quality-related traits in Chinese wheat cultivars in eight environments over four years. A total of 846 significant single nucleotide polymorphisms (SNPs) were identified, explaining approximately 30% of the phenotypic variation on average, and 103 multienvironment-significant SNPs were detected in more than four environments. Quantitative trait loci (QTL) mapping in the biparent population confirmed some important SNP loci. Moreover, it was determined that some important genes were associated with the six quality traits, including some known functional genes and annotated unknown functional genes. Of the annotated unknown functional genes, it was verified that TaRPP13L1 was associated with flour colour. Wheat cultivars or lines with TaRPP13L1-B1a showed extremely significantly higher flour redness and lower yellowness than those with TaRPP13L1-B1b in the Chinese wheat natural population and the doubled haploid (DH) population. Two tetraploid wheat lines with premature stop codons of the TaRPP13L1 gene mutagenized by ethyl methanesulfonate (EMS) showed extremely significantly higher flour redness and lower yellowness than wild type. Our data suggest that the TaRPP13L1 gene plays an important role in modulating wheat flour colour. This study provides useful information for further dissection of the genetic basis of flour colour and also provides valuable genes or genetic loci for marker-assisted selection to improve the process of breeding quality wheat in China.
Assuntos
Cor , Farinha , Triticum/genética , China , Mapeamento Cromossômico , Genes de Plantas , Estudos de Associação Genética , Fenótipo , Polimorfismo de Nucleotídeo ÚnicoRESUMO
PURPOSE: To report the findings in a patient with peripapillary pachychoroid pigment epitheliopathy who demonstrated a retinal pigment epithelial detachment (PED) that was present at some times but not other times. METHODS: A review of 24 months of the clinical course and findings on multimodal imaging, including color fundus photography, fundus autofluorescence, spectral domain optical coherence tomography, and enhanced depth imaging optical coherence tomography. Choroidal thickness was measured by exporting the optical coherence tomography images to ImageJ (National Institutes of Health) for analysis. RESULTS: A 75-year-old Asian woman complaining of metamorphopsia had a relapsing PED but no intraretinal or subretinal fluid. Multimodal imaging demonstrated an orange-reddish appearance and hyperautofluorescence/hypoautofluorescence in the nasal macula, chronically thickened choroid located beneath the PED and peripapillary region, and variability in the presence of Sattler layer of the choroid, with its disappearance in the foveal region during exacerbation of the condition, and its emergence when the PED resolved. CONCLUSION: In pachychoroid pigment epitheliopathy, PED can develop and spontaneously resolve, and variations in choroidal thickness and the presence of Sattler layer may be an indicator of changes in disease activity.
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Doenças da Coroide/diagnóstico por imagem , Descolamento Retiniano/diagnóstico por imagem , Epitélio Pigmentado da Retina/diagnóstico por imagem , Idoso , Feminino , Humanos , Imagem MultimodalRESUMO
Bread wheat is a leading cereal crop worldwide. Limited amount of superior allele loci restricted the progress of molecular improvement in wheat breeding. Here, we revealed new allelic variation distribution for 13 yield-related traits in series of genome-wide association studies (GWAS) using the wheat 90K genotyping assay, characterized in 163 bread wheat cultivars. Agronomic traits were investigated in 14 environments at three locations over 3 years. After filtering SNP data sets, GWAS using 20 689 high-quality SNPs associated 1769 significant loci that explained, on average, ~20% of the phenotypic variation, both detected already reported loci and new promising genomic regions. Of these, repetitive and pleiotropic SNPs on chromosomes 6AS, 6AL, 6BS, 5BL and 7AS were significantly linked to thousand kernel weight, for example BS00021705_51 on 6BS and wsnp_Ex_c32624_41252144 on 6AS, with phenotypic variation explained (PVE) of ~24%, consistently identified in 12 and 13 of the 14 environments, respectively. Kernel length-related SNPs were mainly identified on chromosomes 7BS, 6AS, 5AL and 5BL. Plant height-related SNPs on chromosomes 4DS, 6DL, 2DS and 1BL were, respectively, identified in more than 11 environments, with averaged PVE of ~55%. Four SNPs were confirmed to be important genetic loci in two RIL populations. Based on repetivity and PVE, a total of 41 SNP loci possibly played the key role in modulating yield-related traits of the cultivars surveyed. Distribution of superior alleles at the 41 SNP loci indicated that superior alleles were getting popular with time and modern cultivars had integrated many superior alleles, especially for peduncle length- and plant height-related superior alleles. However, there were still 19 SNP loci showing less than percentages of 50% in modern cultivars, suggesting they should be paid more attention to improve yield-related traits of cultivars in the Yellow and Huai wheat region. This study could provide useful information for dissection of yield-related traits and valuable genetic loci for marker-assisted selection in Chinese wheat breeding programme.
Assuntos
Estudo de Associação Genômica Ampla/métodos , Triticum/genética , Alelos , China , Cromossomos de Plantas/genética , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genéticaRESUMO
KEY MESSAGE: This study cloned two novel TaLox genes on chromosome of 4BS and developed a co-dominant marker, Lox-B23, in bread wheat that showed highly significant association with lipoxygenase activity. Lipoxygenase (Lox), a critical enzyme in the carotenoid biosynthetic pathway, significantly influences the color and processing quality of wheat-based products. Two novel Lox genes, designated TaLox-B2 and TaLox-B3, were cloned on chromosome 4BS of Chinese bread wheat. The deduced amino acid sequence showed that both TaLox-B2 and TaLox-B3 genes encoded an 861-aa protein and possessed a lipoxygenase superfamily domain at the 170-838 interval. Two different TaLox-B2 alleles, designated TaLox-B2a and TaLox-B2b, were subsequently discovered. A co-dominant marker, Lox-B23, was developed based on sequences of TaLox-B2a, TaLox-B2b, and TaLox-B3 genes to precisely distinguish these three alleles in Chinese bread cultivars. Among five allelic combinations of Lox genes at Lox-B1, Lox-B2, and Lox-B3 loci, wheat cultivars with TaLox-B1a/TaLox-B2a/TaLox-B3a combination exhibited the highest Lox activity, whereas those with TaLox-B1a/TaLox-B2b/TaLox-B3b combination significantly showed the lowest Lox activity. A RIL population was used to evaluate the influence of TaLox-B3a gene on Lox activity. Results showed that TaLox-B3a gene could significantly increase the Lox activity in bread wheat. Physical mapping indicated that both TaLox-B2 and TaLox-B3 genes were located on chromosome 4BS in bread wheat. This study provides useful information to further understand the molecular and genetic bases of Lox activity in bread wheat.
Assuntos
Lipoxigenase/genética , Proteínas de Plantas/genética , Triticum/genética , Alelos , Sequência de Bases , Mapeamento Cromossômico , Cromossomos Artificiais de Bacteriófago P1 , Clonagem Molecular , DNA de Plantas/genética , Ligação Genética , Marcadores Genéticos , Dados de Sequência Molecular , Análise de Sequência de DNA , Triticum/enzimologiaRESUMO
The reaction of N,N'-dicyclohexylcarbodiimide (DCCI) with [Cp(2)Yb(o-H(2)NC(6)H(4)S)](2) (Cp = C(5)H(5)) () forms the monomer product Cp(2)Yb[SC(6)H(4)N[double bond, length as m-dash]C(NHCy)(2)] (), indicating that the adjacent NH(2) group can add to the C[double bond, length as m-dash]N double bonds of carbodiimide to construct a neutral guanidine group. When DCCI reacts with [Cp(2)Y(o-H(2)NC(6)H(4)S)](2).2THF (), a dimer product [CpY(mu-eta(2):eta(1)-SC(6)H(4)N[double bond, length as m-dash]C(NHCy)NCy)(THF)](2) () was isolated, through the amino group addition and cyclopentadienyl elimination. Interestingly, on treatment of with one or two equivalent of (i)PrN[double bond, length as m-dash]C[double bond, length as m-dash]N(i)Pr at the same conditions gave an amino group partial addition product CpY(THF)[mu-eta(2):eta(1)-SC(6)H(4)N[double bond, length as m-dash]C(NH(i)Pr)N(i)Pr)](mu-eta(2):eta(1)-SC(6)H(4)NH(2))YCp(2).THF (), where only one NH(2) group can add to the C[double bond, length as m-dash]N double bonds of carbodiimide molecule, another one is remained. However, when we extended this reaction to the gadolinium complex, a novel co-crystalline compound {Cp(2)Gd[SC(6)H(4)N[double bond, length as m-dash]C(NHCy)(2)]}.{CpGd(THF)[mu-eta(2):eta(1)-SC(6)H(4)N[double bond, length as m-dash]C(NHCy)NCy)][mu-eta(2):eta(1)-SC(6)H(4)NH(2)]GdCp(2).THF} () was obtained from the reaction of [Cp(2)Gd(o-H(2)NC(6)H(4)S)](2) () with DCCI. In order to investigate the sequence of addition and the elimination of the cyclopentadienyl group, a deprotonation reaction of the addition product has also been studied. Reaction of CpYb[SC(6)H(4)NC(NH(i)Pr)(2)](2)(THF) (), formed by reaction of Cp(3)Yb with two equivalent of o-aminothiophenol, and subsequently with 2 equiv. of (i)PrN[double bond, length as m-dash]C[double bond, length as m-dash]N(i)Pr, with one equiv. of Cp(3)Yb gave a cyclopentadienyl elimination product [CpYb(mu-eta(2):eta(1)-SC(6)H(4)N[double bond, length as m-dash]C(NH(i)Pr)N(i)Pr)(THF)](2) (). This result reveals that addition of the NH(2) group to carbodiimide is prior to the elimination of cyclopentadienyl group. All of new compounds have been characterized by elemental analysis and spectroscopic properties. The solid-state structures of complexes , and were determined by single-crystal X-ray diffraction.
RESUMO
Most classical template-based frontal face recognition techniques assume that multiple images per person are available for training, while in many real-world applications only one training image per person is available and the test images may be partially occluded or may vary in expressions. This paper addresses those problems by extending a previous local probabilistic approach presented by Martinez, using the self-organizing map (SOM) instead of a mixture of Gaussians to learn the subspace that represented each individual. Based on the localization of the training images, two strategies of learning the SOM topological space are proposed, namely to train a single SOM map for all the samples and to train a separate SOM map for each class, respectively. A soft kappa nearest neighbor (soft kappa-NN) ensemble method, which can effectively exploit the outputs of the SOM topological space, is also proposed to identify the unlabeled subjects. Experiments show that the proposed method exhibits high robust performance against the partial occlusions and variant expressions.