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1.
Nature ; 588(7837): 284-289, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33239781

RESUMO

Genetic diversity is key to crop improvement. Owing to pervasive genomic structural variation, a single reference genome assembly cannot capture the full complement of sequence diversity of a crop species (known as the 'pan-genome'1). Multiple high-quality sequence assemblies are an indispensable component of a pan-genome infrastructure. Barley (Hordeum vulgare L.) is an important cereal crop with a long history of cultivation that is adapted to a wide range of agro-climatic conditions2. Here we report the construction of chromosome-scale sequence assemblies for the genotypes of 20 varieties of barley-comprising landraces, cultivars and a wild barley-that were selected as representatives of global barley diversity. We catalogued genomic presence/absence variants and explored the use of structural variants for quantitative genetic analysis through whole-genome shotgun sequencing of 300 gene bank accessions. We discovered abundant large inversion polymorphisms and analysed in detail two inversions that are frequently found in current elite barley germplasm; one is probably the product of mutation breeding and the other is tightly linked to a locus that is involved in the expansion of geographical range. This first-generation barley pan-genome makes previously hidden genetic variation accessible to genetic studies and breeding.


Assuntos
Cromossomos de Plantas/genética , Genoma de Planta/genética , Hordeum/genética , Internacionalidade , Mutação , Melhoramento Vegetal , Inversão Cromossômica/genética , Mapeamento Cromossômico , Loci Gênicos/genética , Genótipo , Hordeum/classificação , Polimorfismo Genético/genética , Padrões de Referência , Banco de Sementes , Inversão de Sequência , Sequenciamento Completo do Genoma
2.
Cereb Cortex ; 33(5): 2174-2182, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-35567796

RESUMO

Gray matter volume and thickness reductions have been reported in patients with spinocerebellar ataxia type 3 (SCA3), whereas cortical gyrification alterations of this disease remain largely unexplored. Using local gyrification index (LGI) and fractional anisotropy (FA) from structural and diffusion MRI data, this study investigated the cortical gyrification alterations as well as their relationship with white matter microstructural abnormalities in patients with SCA3 (n = 61) compared with healthy controls (n = 69). We found widespread reductions in cortical LGI and white matter FA in patients with SCA3 and that changes in these 2 features were also coupled. In the patient group, the LGI of the left middle frontal gyrus, bilateral insula, and superior temporal gyrus was negatively correlated with the severity of depressive symptoms, and the FA of a cluster in the left cerebellum was negatively correlated with the Scale for the Assessment and Rating of Ataxia scores. Our findings suggest that the gyrification abnormalities observed in this study may account for the clinical heterogeneity in SCA3 and are likely to be mediated by the underlying white matter microstructural abnormalities of this disease.


Assuntos
Doença de Machado-Joseph , Substância Branca , Humanos , Imageamento por Ressonância Magnética , Imagem de Difusão por Ressonância Magnética , Cerebelo , Substância Cinzenta
3.
BMC Nephrol ; 25(1): 161, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730296

RESUMO

BACKGROUND: Previous observational studies have reported that systemic inflammatory regulators are related to the development of chronic kidney disease (CKD); however, whether these associations are causal remains unclear. The current study aimed to investigate the potential causal relationships between systemic inflammatory regulators and CKD and kidney function. METHOD: We performed bidirectional two-sample Mendelian randomization (MR) analyses to infer the underlying causal associations between 41 systemic inflammatory regulators and CKD and kidney function. The inverse-variance weighting (IVW) test was used as the primary analysis method. In addition, sensitivity analyses were executed via the Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO) test and the weighted median test. RESULTS: The findings revealed 12 suggestive associations between 11 genetically predicted systemic inflammatory regulators and CKD or kidney function in the forward analyses, including 4 for CKD, 3 for blood urea nitrogen (BUN), 4 for eGFRcrea and 1 for eGFRcys. In the other direction, we identified 6 significant causal associations, including CKD with granulocyte-colony stimulating factor (GCSF) (IVW ß = 0.145; 95% CI, 0.042 to 0.248; P = 0.006), CKD with stem cell factor (SCF) (IVW ß = 0.228; 95% CI, 0.133 to 0.323; P = 2.40 × 10- 6), eGFRcrea with SCF (IVW ß =-2.90; 95% CI, -3.934 to -1.867; P = 3.76 × 10- 8), eGFRcys with GCSF (IVW ß =-1.382; 95% CI, -2.404 to -0.361; P = 0.008), eGFRcys with interferon gamma (IFNg) (IVW ß =-1.339; 95% CI, -2.313 to -0.366; P = 0.007) and eGFRcys with vascular endothelial growth factor (VEGF) (IVW ß =-1.709; 95% CI, -2.720 to -0.699; P = 9.13 × 10- 4). CONCLUSIONS: Our findings support causal links between systemic inflammatory regulators and CKD or kidney function both in the forward and reverse MR analyses.


Assuntos
Análise da Randomização Mendeliana , Insuficiência Renal Crônica , Humanos , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/sangue , Taxa de Filtração Glomerular , Inflamação/genética , Fator Estimulador de Colônias de Granulócitos/sangue , Fator de Células-Tronco/genética , Fator de Células-Tronco/sangue , Rim/metabolismo , Rim/fisiopatologia , Nitrogênio da Ureia Sanguínea
4.
Plant Biotechnol J ; 21(1): 46-62, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36054248

RESUMO

Divergent selection of populations in contrasting environments leads to functional genomic divergence. However, the genomic architecture underlying heterogeneous genomic differentiation remains poorly understood. Here, we de novo assembled two high-quality wild barley (Hordeum spontaneum K. Koch) genomes and examined genomic differentiation and gene expression patterns under abiotic stress in two populations. These two populations had a shared ancestry and originated in close geographic proximity but experienced different selective pressures due to their contrasting micro-environments. We identified structural variants that may have played significant roles in affecting genes potentially associated with well-differentiated phenotypes such as flowering time and drought response between two wild barley genomes. Among them, a 29-bp insertion into the promoter region formed a cis-regulatory element in the HvWRKY45 gene, which may contribute to enhanced tolerance to drought. A single SNP mutation in the promoter region may influence HvCO5 expression and be putatively linked to local flowering time adaptation. We also revealed significant genomic differentiation between the two populations with ongoing gene flow. Our results indicate that SNPs and small SVs link to genetic differentiation at the gene level through local adaptation and are maintained through divergent selection. In contrast, large chromosome inversions may have shaped the heterogeneous pattern of genomic differentiation along the chromosomes by suppressing chromosome recombination and gene flow. Our research offers novel insights into the genomic basis underlying local adaptation and provides valuable resources for the genetic improvement of cultivated barley.


Assuntos
Hordeum , Hordeum/genética , Genômica , Adaptação Fisiológica/genética , Genes de Plantas
5.
Plant J ; 106(2): 419-434, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33506596

RESUMO

The future of plant cultivar improvement lies in the evaluation of genetic resources from currently available germplasm. Today's gene pool of crop genetic diversity has been shaped during domestication and more recently by breeding. Recent efforts in plant breeding have been aimed at developing new and improved varieties from poorly adapted crops to suit local environments. However, the impact of these breeding efforts is poorly understood. Here, we assess the contributions of both historical and recent breeding efforts to local adaptation and crop improvement in a global barley panel by analysing the distribution of genetic variants with respect to geographic region or historical breeding category. By tracing the impact that breeding had on the genetic diversity of Hordeum vulgare (barley) released in Australia, where the history of barley production is relatively young, we identify 69 candidate regions within 922 genes that were under selection pressure. We also show that modern Australian barley varieties exhibit 12% higher genetic diversity than historical cultivars. Finally, field-trialling and phenotyping for agriculturally relevant traits across a diverse range of Australian environments suggests that genomic regions under strong breeding selection and their candidate genes are closely associated with key agronomic traits. In conclusion, our combined data set and germplasm collection provide a rich source of genetic diversity that can be applied to understanding and improving environmental adaptation and enhanced yields.


Assuntos
Genoma de Planta/genética , Hordeum/genética , Melhoramento Vegetal , Austrália , Produção Agrícola , Domesticação , Genes de Plantas/genética , Variação Genética
6.
Plant J ; 105(5): 1192-1210, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33249667

RESUMO

Shifting from a livestock-based protein diet to a plant-based protein diet has been proposed as an essential requirement to maintain global food sustainability, which requires the increased production of protein-rich crops for direct human consumption. Meanwhile, the lack of sufficient genetic diversity in crop varieties is an increasing concern for sustainable food supplies. Countering this concern requires a clear understanding of the domestication process and dynamics. Narrow-leafed lupin (Lupinus angustifolius L.) has experienced rapid domestication and has become a new legume crop over the past century, with the potential to provide protein-rich seeds. Here, using long-read whole-genome sequencing, we assembled the third-generation reference genome for the narrow-leafed lupin cultivar Tanjil, comprising 20 chromosomes with a total genome size of 615.8 Mb and contig N50 = 5.65 Mb. We characterized the original mutation and putative biological pathway resulting in low seed alkaloid level that initiated the recent domestication of narrow-leafed lupin. We identified a 1133-bp insertion in the cis-regulatory region of a putative gene that may be associated with reduced pod shattering (lentus). A comparative analysis of genomic diversity in cultivars and wild types identified an apparent domestication bottleneck, as precisely predicted by the original model of the bottleneck effect on genetic variability in populations. Our results identify the key domestication genetic loci and provide direct genomic evidence for a domestication bottleneck, and open up the possibility of knowledge-driven de novo domestication of wild plants as an avenue to broaden crop plant diversity to enhance food security and sustainable low-carbon emission agriculture.


Assuntos
Genoma de Planta/genética , Lupinus/genética , Folhas de Planta/genética , Variação Genética/genética , Mutação/genética
7.
Cerebellum ; 21(3): 358-367, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34264505

RESUMO

Spinocerebellar ataxias (SCAs) are a large group of hereditary neurodegenerative diseases characterized by ataxia and dysarthria. Due to high clinical and genetic heterogeneity, many SCA families are undiagnosed. Herein, using linkage analysis, WES, and RP-PCR, we identified the largest SCA36 pedigree in Asia. This pedigree showed some distinct clinical characteristics. Cognitive impairment and gaze palsy are common and severe in SCA36 patients, especially long-course patients. Although no patients complained of hearing loss, most of them presented with hearing impairment in objective auxiliary examination. Voxel-based morphometry (VBM) demonstrated a reduction of volumes in cerebellum, brainstem, and thalamus (corrected P < 0.05). Reduced volumes in cerebellum were also found in presymptomatic carriers. Resting-state functional MRI (R-fMRI) found reduced ReHo values in left cerebellar posterior lobule (corrected P < 0.05). Diffusion tensor imaging (DTI) demonstrated a reduction of FA values in cerebellum, midbrain, superior and inferior cerebellar peduncle (corrected P < 0.05). MRS found reduced NAA/Cr values in cerebellar vermis and hemisphere (corrected P < 0.05). Our findings could provide new insights into management of SCA36 patients. Detailed auxiliary examination are recommended to assess hearing or peripheral nerve impairment, and we should pay more attention to eye movement and cognitive changes in patients. Furthermore, for the first time, our multimodel neuroimaging evaluation generate a full perspective of brain function and structure in SCA36 patients.


Assuntos
Imagem de Tensor de Difusão , Ataxias Espinocerebelares , Cerebelo , Humanos , Imageamento por Ressonância Magnética , Linhagem , Ataxias Espinocerebelares/diagnóstico por imagem , Ataxias Espinocerebelares/genética
8.
Eur Radiol ; 32(7): 4919-4930, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35124718

RESUMO

OBJECTIVES: To identify specific imaging and clinicopathological features of a rare potentially malignant epithelioid variant of renal lipid-poor angiomyolipoma (E-lpAML). METHODS: A total of 20 patients with E-lpAML and 43 patients with other lpAML were retrospectively included. Multiphase computed tomography (CT) imaging features and clinicopathological findings were recorded. Independent predictors for E-lpAML were identified using multivariate logistic regression and were used to construct a diagnostic score for differentiation of E-lpAML from other lpAML. RESULTS: The E-lpAML group consisted of 6 men and 14 women (age median ± SD: 39.45 ± 15.70, range: 16.0-68.0 years). E-lpAML tended to appear as hyperdense mass lesions located at the renal sinus (n = 8, 40%) or at the renal cortex (n = 12, 60%), with a "fast-in and slow-out" enhancement pattern (n = 20, 100%), cystic degeneration (n = 18, 90%), "eyeball" sign (n = 11, 55%), and tumor neo-vasculature (n = 15, 75%) on CT. Multivariate logistic regression analysis showed that the independent predictors for diagnosing E-lpAML were cystic degeneration on CT imaging and CT value of the tumor in corticomedullary phase of enhancement. A predictive model was built with the two predictors, achieving an area under the curve (AUC) of 93.5% (95% confidence interval (95%CI): 84.3-98.2%) with a sensitivity of 95.0% (95%CI: 75.1-99.9%) and a specificity of 83.72% (95%CI: 69.3-93.2%). CONCLUSION: We identified specific CT imaging features and predictors that could contribute to the correct diagnosis of E-lpAML. Our findings should be helpful for clinical management of E-lpAML which could potentially be malignant and may require nephron-sparing surgery while other lpAML tumors which are benign require no intervention. KEY POINTS: • It is important to differentiate renal epithelioid lipid-poor angiomyolipoma (E-lpAML) from other lpAML because of differences in clinical management. • E-lpAML tumors tend to be large hyperdense tumors in the renal sinus with cystic degeneration and "fast-in and slow-out" pattern of enhancement. • Our CT imaging-based predictive model was robust in its performance for predicting E-lpAML from other lpAML tumors.


Assuntos
Angiomiolipoma , Carcinoma de Células Renais , Neoplasias Renais , Adolescente , Adulto , Idoso , Angiomiolipoma/diagnóstico por imagem , Angiomiolipoma/patologia , Carcinoma de Células Renais/patologia , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias Renais/patologia , Lipídeos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
9.
Theor Appl Genet ; 134(9): 2875-2889, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34059938

RESUMO

KEY MESSAGE: Using genomic structural equation modelling, this research demonstrates an efficient way to identify genetically correlating traits and provides an effective proxy for multi-trait selection to consider the joint genetic architecture of multiple interacting traits in crop breeding. Breeding crop cultivars with optimal value across multiple traits has been a challenge, as traits may negatively correlate due to pleiotropy or genetic linkage. For example, grain yield and grain protein content correlate negatively with each other in cereal crops. Future crop breeding needs to be based on practical yet accurate evaluation and effective selection of beneficial trait to retain genes with the best agronomic score for multiple traits. Here, we test the framework of whole-system-based approach using structural equation modelling (SEM) to investigate how one trait affects others to guide the optimal selection of a combination of agronomically important traits. Using ten traits and genome-wide SNP profiles from a worldwide barley panel and SEM analysis, we revealed a network of interacting traits, in which tiller number contributes positively to both grain yield and protein content; we further identified common genetic factors affecting multiple traits in the network of interaction. Our method demonstrates an efficient way to identify genetically correlating traits and underlying pleiotropic genetic factors and provides an effective proxy for multi-trait selection within a whole-system framework that considers the joint genetic architecture of multiple interacting traits in crop breeding. Our findings suggest the promise of a whole-system approach to overcome challenges such as the negative correlation of grain yield and protein content to facilitating quantitative and objective breeding decisions in future crop breeding.


Assuntos
Cromossomos de Plantas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/genética , Genoma de Planta , Melhoramento Vegetal/métodos , Locos de Características Quantitativas , Seleção Genética , Mapeamento Cromossômico/métodos , Polimorfismo de Nucleotídeo Único
10.
Neurosurg Rev ; 44(5): 2933-2941, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33506362

RESUMO

This study aimed to investigate the role of diffusion-weighted imaging (DWI) in predicting tumor consistency, extent of surgical resection, and recurrence in pituitary adenoma (PA). We reviewed a prospectively collected database of surgically treated PA between March 2016 and October 2017. Predictors for extent of resection and recurrence/progression were assessed with logistic and Cox regression analysis. Of the 183 patients, the tumor consistency was found soft in 107 (58.5%) patients, intermediate in 41 (22.4%) patients, and hard in 35 (19.1%) patients. The mean of ADC ratio was 0.92 ± 0.22 for hard tumor, 1.03 ± 0.22 for intermediate tumor, and 1.41 ± 0.62 for soft tumor (P < 0.001). The mean collagen content was 25.86% ± 15.00% for hard tumor, 16.05% ± 9.90% for intermediate tumor, and 5.00% ± 6.00% for soft tumor (P < 0.001). Spearman analysis showed a significant correlation between ADC ratio and collagen content (ρ = - 0.367; P < 0.001). Gross-total resection (GTR) was obtained in 68.3% of patients, and multivariable logistic regression analysis showed that ADC ratio (OR, 12.135; 95% CI, 4.001-36.804; P < 0.001), giant PA (OR, 0.233; 95% CI, 0.105-0.520; P < 0.001), and invasion (OR, 0.459; 95% CI, 0.220-0.960; P = 0.039) were significantly predictive of GTR. Twenty-seven (14.8%) patients suffered recurrence/progression in the mean follow-up of 35.14 months. Invasion (HR, 2.728; 95% CI, 1.262-5.899; P = 0.011) was identified as independent predictors of recurrence/progression. ADC ratio of DWI could be used for preoperative assessment of tumor consistency, tumor collagen content, and extent of surgical resection, which might be useful in preoperative planning for patients with PA.


Assuntos
Adenoma , Neoplasias Hipofisárias , Adenoma/diagnóstico por imagem , Adenoma/cirurgia , Imagem de Difusão por Ressonância Magnética , Humanos , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/cirurgia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos
11.
J Sci Food Agric ; 101(10): 4321-4331, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33417244

RESUMO

BACKGROUND: The levels and ratios of sugar and acid are important contributors to fruit taste. Kumquat is one of the most economically important citrus crops, but information on the soluble sugar and organic acid metabolism in kumquat is limited. Here, two kumquat varieties - 'Rongan' (RA) and its mutant 'Huapi' (HP) - were used to assess soluble sugar and organic acid accumulation and the related genes. RESULTS: Soluble sugars include sucrose, glucose and fructose, while malate, quinic acid and citrate are the dominant organic acids in the fruits of both kumquat varieties. HP accumulated more sugars but fewer organic acids than did RA. Transcriptome analysis revealed 63 and 40 differentially expressed genes involved in soluble sugar and organic acid accumulation, respectively. The genes associated with sugar synthesis and transport, including SUS, SPS, TST, STP and ERD6L, were up-regulated, whereas INVs, FRK and HXK genes related to sugar degradation were down-regulated in HP kumquat. For organic acids, the up-regulation of PEPC and NAD-MDH could accelerate malate accumulation. In contrast, high expression of NAD-IDH and GS resulted in citric acid degradation during HP fruit development. Additionally, the PK, PDH, PEPCK and FBPase genes responsible for the interconversion of soluble sugars and organic acids were also significantly altered in the early development stages in HP. CONCLUSION: The high sugar accumulation in HP fruit was associated with up-regulation of SUS, SPS, TST, STP and ERD6L genes. The PEPCK, PEPC, NAD-MDH, NADP-IDH, GS and FBPase genes played important roles in acid synthesis and degradation in HP kumquat. These findings provide further insight into understanding the mechanisms underlying metabolism of sugars and organic acids in citrus. © 2021 Society of Chemical Industry.


Assuntos
Ácidos/metabolismo , Frutas/metabolismo , Proteínas de Plantas/genética , Rutaceae/genética , Açúcares/metabolismo , Ácidos/análise , Ácido Cítrico/metabolismo , Frutas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Malatos/metabolismo , Proteínas de Plantas/metabolismo , Rutaceae/metabolismo
12.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(9): 1003-1009, 2021.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-34707011

RESUMO

OBJECTIVES: T1 mapping can noninvasively quantify the native longitudinal relaxation time (T1 value) of myocardium and provide more information on myocardial fibrosis based on late gadolinium enhancement (LGE). However, the traditional approach of measuring T1 value limits the popularization and application of this technology in clinic because the whole short axis (SAX) of myocardium is required in the regions of interest (ROI). This study aims to evaluate the diagnostic ability of native T1 value obtained by comparison between the midventricular septum (ConSept) and SAX approaches in diffuse myocardial lesions. METHODS: Retrospective analysis was performed on 38 patients with non-ischemic dilated cardiomyopathy (NIDCM) and 27 healthy controls who underwent T1 mapping and gadolinium delayed enhancement (LGE) scanning on a 3.0T cardiac magnetic resonance (CMR) in Xiangya Hospital of Central South University. Patients with NIDCM were divided into a LGE positive group and a LGE negative group according to the presence or absence of LGE. The native T1 value was measured by the ROI placed in the ConSept and SAX, respectively. The ability to distinguish the impaired myocardium from the healthy myocardium and the native T1 values of the myocardium measured by the 2 approaches were compared between the NIDCM group and the control group. RESULTS: The native T1 values of NIDCM group using ConSept or SAX approach were significantly higher than those in the control group (all P<0.001), and the native T1 values in the LGE positive group were greater than those in the LGE negative group (all P<0.05). There was no significant difference in T1 value of middle, basal, and apical layer between the ConSept approach and SAX approach (all P>0.05). ConSept and SAX approaches had a good consistency [concordance correlation coefficient (CCC)=0.954]. CONCLUSIONS: Comparing to the SAX approach, ConSept approach is a simple and equivalent method to measure the native T1 value of myocardium and is suitable for clinical application.


Assuntos
Cardiomiopatia Dilatada , Cardiomiopatia Dilatada/diagnóstico por imagem , Meios de Contraste , Gadolínio , Humanos , Imagem Cinética por Ressonância Magnética , Miocárdio , Valor Preditivo dos Testes , Estudos Retrospectivos
13.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(4): 385-392, 2021 Apr 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-33967085

RESUMO

OBJECTIVES: Glioma is the most common intracranial primary tumor in central nervous system. Glioma grading possesses important guiding significance for the selection of clinical treatment and follow-up plan, and the assessment of prognosis. This study aims to explore the feasibility of logistic regression model based on radiomics to predict glioma grading. METHODS: Retrospective analysis was performed on 146 glioma patients with confirmed pathological diagnosis from January, 2012 to December, 2018. A total of 41 radiomics features were extracted from contrast-enhanced T1-weighted imaging (T1WI+C) lesion by manual segmentation. Least absolute shrinkage and selection operator (LASSO) was used to select the most-predictive radiomics features for pathological grading and to calculate radiomics score (Rad-score) of each patient. A logistic regression model was built to explore the correlation between giloma grading and Rad-score. Receiver operating characteristic (ROC) curve was performed to evaluate the model's predictive ability with area under the curve (AUC) for the evaluation index. Hosmer-Lemeshow test was used to measure the model's predictive accuracy. RESULTS: A total of 5 imaging features selected by LASSO were used to establish a logistic regression model for predicting glioma grading. The model showed good discrimination with AUC value of 0.919. Hosmer-Lemeshow test showed no significant difference between the calibration curve and the ideal curve (P=0.808), indicating high predictive accuracy of the model. CONCLUSIONS: The logistic regression model using radiomics exhibits a relatively high accuracy for predicting glioma grading, which may serve as a complementary tool for preoperative prediction of giloma grading.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Humanos , Modelos Logísticos , Imageamento por Ressonância Magnética , Curva ROC , Estudos Retrospectivos
14.
Hum Brain Mapp ; 41(3): 710-725, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31663232

RESUMO

Although diabetic peripheral neuropathy (DPN) has long been considered a disease of the peripheral nervous system, recent neuroimaging studies have shown that alterations in the central nervous system may play a crucial role in its pathogenesis. Here, we used surface-based morphometry (SBM) and tract-based spatial statistics (TBSS) to investigate gray matter (GM) and white matter (WM) differences between patients with DPN (n = 67, 44 painless and 23 painful) and healthy controls (HCs; n = 88). Compared with HCs, patients with DPN exhibited GM abnormalities in the pre- and postcentral gyrus and in several deep GM nuclei (caudate, putamen, medial pallidum, thalamus, and ventral nuclear). They also exhibited altered WM tracts (corticospinal tract, spinothalamic tract, and thalamocortical projecting fibers). These findings suggest impaired motor and somatosensory pathways in DPN. Further, patients with DPN (particularly painful DPN) exhibited morphological differences in the cingulate, insula, prefrontal cortex, and thalamus, as well as impaired WM integrity in periaqueductal WM and internal and external capsules. This suggests pain-perception/modulation pathways are altered in painful DPN. Intermodal correlation analyses found that the morphological indices of the brain regions identified by the SBM analysis were significantly correlated with the fractional anisotropy of brain regions identified by the TBSS analysis, suggesting that the GM and WM alterations were tightly coupled. Overall, our study showed sensorimotor and pain-related GM and WM alterations in patients with DPN, which might be involved in the development of DPN.


Assuntos
Córtex Cerebral/patologia , Diabetes Mellitus Tipo 2/patologia , Neuropatias Diabéticas/patologia , Substância Cinzenta/patologia , Atividade Motora , Neuralgia/patologia , Distúrbios Somatossensoriais/patologia , Substância Branca/patologia , Adulto , Idoso , Córtex Cerebral/diagnóstico por imagem , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Neuropatias Diabéticas/diagnóstico por imagem , Neuropatias Diabéticas/etiologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/patologia , Neuralgia/diagnóstico por imagem , Neuralgia/etiologia , Neuroimagem , Distúrbios Somatossensoriais/diagnóstico por imagem , Distúrbios Somatossensoriais/etiologia , Substância Branca/diagnóstico por imagem
15.
BMC Plant Biol ; 20(1): 346, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32698771

RESUMO

BACKGROUND: Drought is projected to become more frequent and severe in a changing climate, which requires deep sowing of crop seeds to reach soil moisture. Coleoptile length is a key agronomic trait in cereal crops such as barley, as long coleoptiles are linked to drought tolerance and improved seedling establishment under early water-limited growing conditions. RESULTS: In this study, we detected large genetic variation in a panel of 328 diverse barley (Hordeum vulgare L.) accessions. To understand the overall genetic basis of barley coleoptile length, all accessions were germinated in the dark and phenotyped for coleoptile length after 2 weeks. The investigated barleys had significant variation for coleoptile length. We then conducted genome-wide association studies (GWASs) with more than 30,000 molecular markers and identified 8 genes and 12 intergenic loci significantly associated with coleoptile length in our barley panel. The Squamosa promoter-binding-like protein 3 gene (SPL3) on chromosome 6H was identified as a major candidate gene. The missense variant on the second exon changed serine to alanine in the conserved SBP domain, which likely impacted its DNA-binding activity. CONCLUSION: This study provides genetic loci for seedling coleoptile length along with candidate genes for future potential incorporation in breeding programmes to enhance early vigour and yield potential in water-limited environments.


Assuntos
Cotilédone/genética , Hordeum/genética , Proteínas de Plantas/genética , América , Austrália , Mapeamento Cromossômico , Cotilédone/fisiologia , Europa (Continente) , Marcadores Genéticos , Genética Populacional , Estudo de Associação Genômica Ampla , Germinação , Desequilíbrio de Ligação , Locos de Características Quantitativas
16.
Theor Appl Genet ; 133(7): 2095-2103, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32193568

RESUMO

KEY MESSAGE: A major grain length QTL on chromosome 2H was fine mapped to a 140.9 Kb region containing three genes. Increasing yield is an important target for barley breeding programs. One approach to increase yield is by enhancing individual grain weights through the regulation of grain size. Fine mapping major grain size-related quantitative trait loci is necessary for future marker-assisted selection strategies, yet studies of this nature are limited in barley. In the present study, we utilised a doubled haploid population derived from two Australian malt barley varieties, Vlamingh and Buloke, coupled with extensive genotypic and phenotypic data from three independent environments. A major grain length locus identified on chromosome 2H designated qGL2H was fine mapped to a 140.9 Kb interval. qGL2H was able to account for 25.4% of the phenotypic variation for grain length and 10.2% for grain yield. Underlying qGL2H were three high-confidence predicted genes. One of these genes encodes a MYB transcription factor and represents a promising candidate for further genetic research.


Assuntos
Mapeamento Cromossômico , Hordeum/genética , Locos de Características Quantitativas , Sementes/crescimento & desenvolvimento , Austrália , Ligação Genética , Genótipo , Haploidia , Fenótipo , Polimorfismo de Nucleotídeo Único , Análise de Componente Principal
17.
Theor Appl Genet ; 133(7): 2307-2321, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32405768

RESUMO

KEY MESSAGE: An effective and stable quantitative resistance locus, QSc.VR4, was fine mapped, characterized and physically anchored to the short arm of 4H, conferring adult plant resistance to the fungus Rhynchosporium commune in barley. Scald caused by Rhynchosporium commune is one of the most destructive barley diseases worldwide. Accumulation of adult plant resistance (APR) governed by multiple resistance alleles is predicted to be effective and long-lasting against a broad spectrum of pathotypes. However, the molecular mechanisms that control APR remain poorly understood. Here, quantitative trait loci (QTL) analysis of APR and fine mapping were performed on five barley populations derived from a common parent Vlamingh, which expresses APR to scald. Two QTLs, designated QSc.VR4 and QSc.BR7, were detected from a cross between Vlamingh and Buloke. Our data confirmed that QSc.VR4 is an effective and stable APR locus, residing on the short arm of chromosome 4H, and QSc.BR7 derived from Buloke may be an allele of reported Rrs2. High-resolution fine mapping revealed that QSc.VR4 is located in a 0.38 Mb genomic region between InDel markers 4H2282169 and 4H2665106. The gene annotation analysis and sequence comparison suggested that a gene cluster containing two adjacent multigene families encoding leucine-rich repeat receptor kinase-like proteins (LRR-RLKs) and germin-like proteins (GLPs), respectively, is likely contributing to scald resistance. Adult plant resistance (APR) governed by QSc.VR4 may confer partial levels of resistance to the fungus Rhynchosporium commune and, furthermore, be an important resource for gene pyramiding that may contribute broad-based and more durable resistance.


Assuntos
Ascomicetos/patogenicidade , Mapeamento Cromossômico , Resistência à Doença/genética , Hordeum/genética , Doenças das Plantas/genética , Alelos , Cromossomos de Plantas , Genes de Plantas , Marcadores Genéticos , Genótipo , Hordeum/microbiologia , Limite de Detecção , Modelos Genéticos , Família Multigênica , Fenótipo , Doenças das Plantas/microbiologia , Locos de Características Quantitativas
18.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(8): 980-987, 2020 Aug 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-33053542

RESUMO

OBJECTIVES: To evaluate the image quality of magnetic resonance 3D-sampling perfection with application-optimized contrasts by using different filp angle evolutions (3D-SPACE) sequence combined with different fusion methods in image fusion technology and the application value of fusion technology in preoperative evaluation of pituitary macroadenoma. METHODS: We collected MRI data of 43 patients with pituitary macroadenoma confirmed by Xiangya Hospital of Central South University, including collecting conventional MRI scan+enhancement, 3D-SPACE T2WI, and 3D-SPACE T1WI+C image data. 3D-SPACE sequence fusion was used in 6 combinations of 3D-SPACE T2WI/3D-SPACE T1WI+C, which were normal phase+normal phase, reverse phase+normal phase, normal phase+reverse phase, reverse phase+reverse phase, and normal phase pseudo color+normal phase, normal phase+normal phase pseudo color. Two senior radiologists used semi-quantitative methods to evaluate and compare the image quality of different combinations to obtain the best fusion mode. According to the degree of tumor invasion of the optic chiasma, oculomotor nerve, and cavernous sinus vessels, the MRI enhancement, 3D-SPACE T2WI, 3D-SPACE T1WI+C, and 2 3D-SPACE sequence fusion images were performed according to a three-level score system. Taking the intraoperative observation as the gold standard, Fisher probability exact method was used to compare different sequences to show the difference between the degree of invasion of the pituitary macroadenoma to the surrounding tissue and the intraoperative results. RESULTS: The Kruskal-Wallis H rank sum test showed that among the 6 image fusion modes, 3D-SPACE T1WI+C normal phase pseudo-color and 3D-SPACE T2WI normal phase fusion images had the best quality (P<0.05). No significance was observed among the 4 groups in the evaluation of consistency between the intraoperative findings and the graphically displayed extent of tumor invasion into oculomotor nerve (both level I, II, and III, P>0.05). The 3D-SPACE T2WI/3D-SPACE T1WI+C fusion images and the 3D-SPACE T2WI images showed better performance in the evaluation of consistency between the intraoperative findings and the graphically displayed extent of tumor invasion into optic chiasma (level II and III) than that in other two kinds of imaging data of the MRI enhancement group and 3D-SPACE T1WI+C group (P<0.01, P<0.05, respectively), with no significance being observed in level I. The 3D-SPACE T2WI/3D-SPACE T1WI+C fusion images and the 3D-SPACE T1WI+C images showed better performance in the evaluation of consistency between the intraoperative findings and the graphically displayed extent of tumor invasion into cavernous sinus vessels (level II) than that in other two kinds of imaging data of the MRI enhancement group and 3D-SPACE T2WI group (P<0.01, P<0.05, respectively), with no significance being observed in level I and III. CONCLUSIONS: Magnetic resonance 3D-SPACE sequence combined with image fusion technology is better than conventional magnetic resonance sequence for showing pituitary macroadenoma invasion of skull base vascular nerves. The invasion is better than the 3D-SPACE sequence alone, showing that the relationship between tumor and cavernous sinus vascular grade II better than the 3D-SPACE sequence alone. It has good application prospects for preoperative risk assessment and surgical plan.


Assuntos
Aumento da Imagem , Neoplasias Hipofisárias , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia
19.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(5): 576-581, 2020 May 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-32879110

RESUMO

OBJECTIVES: To explore and analyze the epidemic features of coronavirus disease 2019 (COVID-19) in Hunan Province from January 21, 2020 to March 14, 2020, as well as to investigate the COVID-19 epidemics in each city of Hunan Province. METHODS: The epidemic data was obtained from the official website of Hunan Province's Health Commission. The data of each city of Hunan Province was analyzed separately. Spatial distribution of cumulative confirmed COVID-19 patients and the cumulative occurrence rate was drawn by ArcGIS software for each city in Hunan Province. Some regional indexes were also compared with that in the whole country. RESULTS: The first patient was diagnosed in January 21, sustained patient growth reached its plateau in around February 17. Up to March 14, the cumulative confirmed COVID-19 patients stopped at 1 018. The cumulative occurrence rate of COVID-19 patients was 0.48 per 0.1 million person. The number of cumulative severe patients was 150 and the number of cumulative dead patients was 4. The mortality rate (0.39%) and the cure rate (99.6%) in Hunan Province was significantly lower and higher respectively than the corresponding average rate in the whole country (0.90% and 96.2%, Hubei excluded). The first 3 cities in numbers of the confirmed patients were Changsha, Yueyang, and Shaoyang. While sorted by the cumulative occurrence rate, the first 3 cities in incidence were Changsha, Yueyang, and Zhuzhou. CONCLUSIONS: The epidemic of COVID-19 spread out smoothly in Hunan Province. The cities in Hunan Province implement anti-disease strategies based on specific situations on their own and keep the epidemic in the range of controllable.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/mortalidade , Pneumonia Viral/epidemiologia , Pneumonia Viral/mortalidade , Betacoronavirus , COVID-19 , China/epidemiologia , Cidades/epidemiologia , Humanos , Pandemias , SARS-CoV-2
20.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(3): 269-274, 2020 Mar 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-32386018

RESUMO

The coronavirus disease 2019 (COVID-19) has attracted extensive attention all around the world recently. Early screening, early diagnosis, early isolation, and early treatment remain the most effective prevention and control measures. Computed tomography (CT) plays a vital role in the screening, diagnosis, treatment, and follow-up of COVID-19, especially in the early screening, with a higher sensitivity than that of real-time fluorescence RT-PCR. The combination of CT and artificial intelligence has the potential to help clinicians in improving the diagnostic accuracy and working efficiency.


Assuntos
Betacoronavirus , Infecções por Coronavirus/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Inteligência Artificial , COVID-19 , Humanos , Pandemias , SARS-CoV-2 , Tomografia Computadorizada por Raios X
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