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1.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33658387

RESUMO

Although genome-sequence assemblies are available for a growing number of plant species, gene-expression responses to stimuli have been cataloged for only a subset of these species. Many genes show altered transcription patterns in response to abiotic stresses. However, orthologous genes in related species often exhibit different responses to a given stress. Accordingly, data on the regulation of gene expression in one species are not reliable predictors of orthologous gene responses in a related species. Here, we trained a supervised classification model to identify genes that transcriptionally respond to cold stress. A model trained with only features calculated directly from genome assemblies exhibited only modest decreases in performance relative to models trained by using genomic, chromatin, and evolution/diversity features. Models trained with data from one species successfully predicted which genes would respond to cold stress in other related species. Cross-species predictions remained accurate when training was performed in cold-sensitive species and predictions were performed in cold-tolerant species and vice versa. Models trained with data on gene expression in multiple species provided at least equivalent performance to models trained and tested in a single species and outperformed single-species models in cross-species prediction. These results suggest that classifiers trained on stress data from well-studied species may suffice for predicting gene-expression patterns in related, less-studied species with sequenced genomes.


Assuntos
Resposta ao Choque Frio , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Modelos Genéticos , Poaceae , Transcrição Gênica , Poaceae/genética , Poaceae/metabolismo , Especificidade da Espécie
2.
BMC Genomics ; 22(1): 86, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33509071

RESUMO

BACKGROUND: The number of panicles per plant, number of grains per panicle, and 1000-grain weight are important factors contributing to the grain yield per plant in rice. The Rice Diversity Panel 1 (RDP1) contains a total of 421 purified, homozygous rice accessions representing diverse genetic variations within O. sativa. The release of High-Density Rice Array (HDRA, 700 k SNPs) dataset provides a new opportunity to discover the genetic variants of panicle architectures in rice. RESULTS: In this report, a new method genome-phenome wide association study (GPWAS) was performed with 391 individuals and 27 traits derived from RDP1 to scan the relationship between the genes and multi-traits. A total of 1985 gene models were linked to phenomic variation with a p-value cutoff of 4.49E-18. Besides, 406 accessions derived from RDP1 with 411,066 SNPs were used to identify QTLs associated with the total spikelets number per panicle (TSNP), grain number per panicle (GNP), empty grain number per panicle (EGNP), primary branch number (PBN), panicle length (PL), and panicle number per plant (PN) by GLM, MLM, FarmCPU, and BLINK models for genome-wide association study (GWAS) analyses. A total of 18, 21, 18, 17, 15, and 17 QTLs were identified tightly linked with TSNP, GNP, EGNP, PBN, PL, and PN, respectively. Then, a total of 23 candidate genes were mapped simultaneously using both GWAS and GPWAS methods, composed of 6, 4, 5, 4, and 4 for TSNP, GNP, EGNP, PBN, and PL. Notably, one overlapped gene (Os01g0140100) were further investigated based on the haplotype and gene expression profile, indicating this gene might regulate the TSNP or panicle architecture in rice. CONCLUSIONS: Nearly 30 % (30/106) QTLs co-located with the previous published genes or QTLs, indicating the power of GWAS. Besides, GPWAS is a new method to discover the relationship between genes and traits, especially the pleiotropy genes. Through comparing the results from GWAS and GPWAS, we identified 23 candidate genes related to panicle architectures in rice. This comprehensive study provides new insights into the genetic basis controlling panicle architectures in rice, which lays a foundation in rice improvement.


Assuntos
Estudo de Associação Genômica Ampla , Oryza , Grão Comestível/genética , Humanos , Oryza/genética , Fenômica , Locos de Características Quantitativas
3.
BMC Genomics ; 22(1): 579, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34325653

RESUMO

BACKGROUND: Dendrobium officinale, an endangered Chinese herb, possesses extensive therapeutic effects and contains bioactive ingredients such as major polysaccharides, alkaloids, and minimal flavonoids. We first obtained the protocorm-like bodies (PLBs) of this plant through tissue culture in order to determine the distribution of the main secondary metabolites in each organelle and the PLBs. We then analyzed the correlation between gene expression level from comparative transcriptome sequencing and metabolite content in different organs to identify putative genes encoding enzymes involved in the biosynthesis of polysaccharides, alkaloids, and flavonoids. RESULTS: We used seeds as explants for protocorm induction and PLB propagation of D. officinale. The optimal medium formula for PLB propagation was 1/2 MS + α-NAA 0.5 mg·L- 1 + 6-BA 1.0 mg·L- 1 + 2, 4-D 1.5-2.0 mg·L- 1 + potato juice 100 g·L- 1. Stems, PLBs and leaves of D. officinale had the highest content of polysaccharides, alkaloids and flavonoids, respectively. Naringenin was only produced in stem; however, PLBs with high alkaloid content can replace other organs producing alkaloids. The hot water extraction method outperformed the ultrasound-assisted extraction method for extracting polysaccharides from D. officinale. A comparative transcriptome analysis of PLBs and leaves of D. officinale revealed differential expression of genes encoding enzymes involved in polysaccharide, alkaloid and flavonoid biosynthetic pathways. Putative genes encoding enzymes involved in these biosynthetic pathways were identified. Notably, we identified genes encoding the alkaloid biosynthesis enzymes strictosidine ß-D-Glucosidase, geissoschizine synthase and vinorine synthase in D. officinale. CONCLUSIONS: The identification of candidate genes encoding enzymes involved in metabolite biosynthesis will help to explore and protect this endangered species and facilitate further analysis of the molecular mechanism of secondary metabolite biosynthesis in D. officinale.


Assuntos
Alcaloides , Dendrobium , Dendrobium/genética , Perfilação da Expressão Gênica , Folhas de Planta/genética , Transcriptoma
4.
Planta ; 255(1): 26, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34940902

RESUMO

MAIN CONCLUSION: The Albizia julibrissin chloroplasts have a classical chloroplast genome structure, containing 93 coding genes and 34 non-coding genes. Our research provides basic data for plant phylogenetic evolutionary studies. There is limited genomic information available for the important Chinese herb Albizia julibrissin Durazz. In this study, we constructed the chloroplast (Cp) genome of A. julibrissin. The length of the assembled Cp genome was 175,922 bp consisting of four conserved regions: a 5145 bp small single-copy (SSC) region, a 91,323 bp large single-copy (LSC) region, and two identical length-inverted repeat (IR) regions (39,725 bp). This Cp genome included 34 non-coding RNAs and 93 unique genes, the former contains 30 transfer and 4 ribosomal RNA genes. Gene annotation indicated some of the coding genes (82) in the A. julibrissin Cp genome classified in the Leguminosae family, with some to other related families (11). The results show that low GC content (36.9%) and codon bias towards A- or T-terminal codons may affect the frequency of gene codon usage. The sequence analysis identified 30 forward, 18 palindrome, and 1 reverse repeat > 30 bp length, and 149 simple sequence repeats (SSR). Fifty-five RNA editing sites in the Cp of A. julibrissin were predicted, most of which are C-to-U conversions. Analysis of the reverse repeat expansion or contraction and divergence area between several species, including A. julibrissin, was performed. The phylogenetic tree revealed that A. julibrissin was most closely related to Albizia odoratissima and Albizia bracteata, followed by Samanea saman, forming an evolutionary branch with Mimosa pudica and Leucaena trichandra. The research results are helpful for breeding and genetic improvement of A. julibrissin, and also provide valuable information for understanding the evolution of this plant.


Assuntos
Albizzia , Fabaceae , Genoma de Cloroplastos , Composição de Bases , Filogenia
5.
Mol Cell Proteomics ; 18(12): 2359-2372, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31492684

RESUMO

Lysine succinylation has been recognized as a post-translational modification (PTM) in recent years. It is plausible that succinylation may have a vaster functional impact than acetylation because of bulkier structural changes and more significant charge differences on the modified lysine residue. Currently, however, the quantity and identity of succinylated proteins and their corresponding functions in cereal plants remain largely unknown. In this study, we estimated the native succinylation occupancy on lysine was between 2% to 10% in developing rice seeds. Eight hundred fifty-four lysine succinylation sites on 347 proteins have been identified by a thorough investigation in developing rice seeds. Six motifs were revealed as preferred amino acid sequence arrangements for succinylation sites, and a noteworthy motif preference was identified in proteins associated with different biological processes, molecular functions, pathways, and domains. Remarkably, heavy succinylation was detected on major seed storage proteins, in conjunction with critical enzymes involved in central carbon metabolism and starch biosynthetic pathways for rice seed development. Meanwhile, our results showed that the modification pattern of in vitro nonenzymatically succinylated proteins was different from those of the proteins isolated from cells in Western blots, suggesting that succinylation is not generated via nonenzymatic reaction in the cells, at least not completely. Using the acylation data obtained from the same rice tissue, we mapped many sites harboring lysine succinylation, acetylation, malonylation, crotonylation, and 2-hydroxisobutyrylation in rice seed proteins. A striking number of proteins with multiple modifications were shown to be involved in critical metabolic events. Given that these modification moieties are intermediate products of multiple cellular metabolic pathways, these targeted lysine residues may mediate the crosstalk between different metabolic pathways via modifications by different moieties. Our study exhibits a platform for extensive investigation of molecular networks administrating cereal seed development and metabolism via PTMs.


Assuntos
Lisina/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Processamento de Proteína Pós-Traducional , Succinatos/metabolismo , Acetilação , Acil Coenzima A/metabolismo , Western Blotting , Domínio Catalítico , Sementes/metabolismo
6.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281180

RESUMO

The sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae) (SCA), has become a major pest of grain sorghum since its appearance in the USA. Several grain sorghum parental lines are moderately resistant to the SCA. However, the molecular and genetic mechanisms underlying this resistance are poorly understood, which has constrained breeding for improved resistance. RNA-Seq was used to conduct transcriptomics analysis on a moderately resistant genotype (TAM428) and a susceptible genotype (Tx2737) to elucidate the molecular mechanisms underlying resistance. Differential expression analysis revealed differences in transcriptomic profile between the two genotypes at multiple time points after infestation by SCA. Six gene clusters had differential expression during SCA infestation. Gene ontology enrichment and cluster analysis of genes differentially expressed after SCA infestation revealed consistent upregulation of genes controlling protein and lipid binding, cellular catabolic processes, transcription initiation, and autophagy in the resistant genotype. Genes regulating responses to external stimuli and stress, cell communication, and transferase activities, were all upregulated in later stages of infestation. On the other hand, expression of genes controlling cell cycle and nuclear division were reduced after SCA infestation in the resistant genotype. These results indicate that different classes of genes, including stress response genes and transcription factors, are responsible for countering the physiological effects of SCA infestation in resistant sorghum plants.


Assuntos
Afídeos/fisiologia , Defesa das Plantas contra Herbivoria/genética , Sorghum/genética , Animais , Suscetibilidade a Doenças , Grão Comestível/genética , Expressão Gênica , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Genótipo , Controle Biológico de Vetores/métodos , Melhoramento Vegetal/métodos , Sorghum/parasitologia , Transcriptoma
7.
BMC Plant Biol ; 20(1): 441, 2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32972357

RESUMO

BACKGROUND: Rice is an important human staple food vulnerable to heavy metal contamination leading to serious concerns. High yield with low heavy metal contamination is a common but highly challenging goal for rice breeders worldwide due to lack of genetic knowledge and markers. RESULTS: To identify candidate QTLs and develop molecular markers for rice yield and heavy metal content, a total of 191 accessions from the USDA Rice mini-core collection with over 3.2 million SNPs were employed to investigate the QTLs. Sixteen ionomic and thirteen agronomic traits were analyzed utilizing two univariate (GLM and MLM) and two multivariate (MLMM and FarmCPU) GWAS methods. 106, 47, and 97 QTLs were identified for ionomics flooded, ionomics unflooded, and agronomic traits, respectively, with the criterium of p-value < 1.53 × 10- 8, which was determined by the Bonferroni correction for p-value of 0.05. While 49 (~ 20%) of the 250 QTLs were coinciding with previously reported QTLs/genes, about 201 (~ 80%) were new. In addition, several new candidate genes involved in ionomic and agronomic traits control were identified by analyzing the DNA sequence, gene expression, and the homologs of the QTL regions. Our results further showed that each of the four GWAS methods can identify unique as well as common QTLs, suggesting that using multiple GWAS methods can complement each other in QTL identification, especially by combining univariate and multivariate methods. CONCLUSIONS: While 49 previously reported QTLs/genes were rediscovered, over 200 new QTLs for ionomic and agronomic traits were found in the rice genome. Moreover, multiple new candidate genes for agronomic and ionomic traits were identified. This research provides novel insights into the genetic basis of both ionomic and agronomic variations in rice, establishing the foundation for marker development in breeding and further investigation on reducing heavy-metal contamination and improving crop yields. Finally, the comparative analysis of the GWAS methods showed that each method has unique features and different methods can complement each other.


Assuntos
Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Produtos Agrícolas/genética , Marcadores Genéticos , Estudo de Associação Genômica Ampla , Oryza/genética , Locos de Características Quantitativas/genética , Fenótipo , Banco de Sementes , Estados Unidos , United States Department of Agriculture
8.
Biochim Biophys Acta Proteins Proteom ; 1866(3): 451-463, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29313810

RESUMO

Protein lysine acetylation is a highly conserved post-translational modification with various biological functions. However, only a limited number of acetylation sites have been reported in plants, especially in cereals, and the function of non-histone protein acetylation is still largely unknown. In this report, we identified 1003 lysine acetylation sites in 692 proteins of developing rice seeds, which greatly extended the number of known acetylated sites in plants. Seven distinguished motifs were detected flanking acetylated lysines. Functional annotation analyses indicated diverse biological processes and pathways engaged in lysine acetylation. Remarkably, we found that several key enzymes in storage starch synthesis pathway and the main storage proteins were heavily acetylated. A comprehensive comparison of the rice acetylome, succinylome, ubiquitome and phosphorylome with available published data was conducted. A large number of proteins carrying multiple kinds of modifications were identified and many of these proteins are known to be key enzymes of vital metabolic pathways. Our study provides extending knowledge of protein acetylation. It will have critical reference value for understanding the mechanisms underlying PTM mediated multiple signal integration in the regulation of metabolism and development in plants.


Assuntos
Lisina/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Sementes/metabolismo , Acetilação , Sequência de Aminoácidos , Vias Biossintéticas , Oryza/crescimento & desenvolvimento , Peptídeos/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Proteômica/métodos , Sementes/crescimento & desenvolvimento , Amido/biossíntese , Ácido Succínico/metabolismo , Espectrometria de Massas em Tandem , Ubiquitinação
10.
Eur Spine J ; 25(12): 3952-3961, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27448809

RESUMO

PURPOSE: To determine if dynamic contrast-enhanced MRI (DCE-MRI) could correlate well with invasive angiography in the characterization of spinal tumor vascularity. METHODS: Totally 40 patients with untreated spinal tumors underwent MRI before preoperative angiography and embolization. Tumors were assigned to hypervascular, moderate, or hypovascular groups based on angiographic appearance. Tumor vascularity was also evaluated with enhancement degree on standard MR and with DCE-MRI parameters via ROI analysis of enhanced tumor area. The Spearman correlation coefficient was calculated to determine the correlation between the degree of angiographic vascularity and enhancement on MRI and DCE-MRI parameters. ROC analysis was conducted to assess the appropriate cut-off value. RESULTS: There were 12 hypervascular, 12 moderate, and 16 hypovascular tumors, respectively. The Spearman correlation coefficient between DCE-MRI parameter and the degree of angiographic vascularity was 0.899 (RSlopemax), 0.847 (Slopemax), 0.697 (E max), 0.694 (ERmax), and -0.587 (TTP), respectively, which showed excellent-to-moderate relationships. The RSlopemax cut-off value of 1.325 provided the highest specificity of 100 % and sensitivity of 87.5 % in predicting hypovascular tumors and the value of 1.85 provided the highest sensitivity of 100 % and specificity of 96.4 % in characterizing hypervascular ones. CONCLUSIONS: DCE-MRI is an accurate technique for the assessment of spinal tumor vascularity, which may have a potential value in the decision-making of preoperative embolization.


Assuntos
Angiografia/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias da Medula Espinal/diagnóstico por imagem , Adolescente , Adulto , Idoso , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/diagnóstico por imagem , Sensibilidade e Especificidade , Adulto Jovem
11.
Tumour Biol ; 36(6): 4453-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25608840

RESUMO

MicroRNAs (miRNAs) are critical for cancer development and progression. Elucidating the underlying mechanism of miRNAs in carcinogenesis may lead to novel diagnostic and therapeutic strategies for malignancy. In this study, we found that miR-511 expression was markedly downregulated in hepatocellular carcinoma (HCC) cell lines and tissues. Phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3) was identified as a direct target of miR-511 and miR-511 expression inversely correlated with PIK3R3 mRNA expression in clinical HCC tissues. We further demonstrated that miR-511 suppressed HCC cell proliferation, migration, and invasion by repressing PIK3R3 expression. Investigations of possible mechanisms underlying these results revealed that miR-511 inhibited the phosphorylation of AKT and mTOR, which are key participants in the AKT/mTOR pathway. Taken together, our findings provide new insights into tumor suppression by miR-511 by negatively regulating the PIK3R3/AKT/mTOR signaling pathway.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/biossíntese , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Humanos , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Invasividade Neoplásica/genética , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/genética
12.
Abdom Imaging ; 39(2): 323-33, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24389893

RESUMO

OBJECTIVE: The purpose of this study was to evaluate MRI features for the differentiation of hepatic angiomyolipoma (HAML) from fat-containing hepatocellular carcinoma. METHODS: We retrospectively reviewed the MRI findings of 20 patients with 22 hepatic angiomyolipomas and 25 patients with fat-containing hepatocellular carcinomas before surgery. The MRI features and apparent diffusion coefficient (ADC) for the two types of tumors were compared and analyzed. RESULTS: Fat was not detected in nine (40.9%) of the angiomyolipomas. An enhancement pattern of the washout area was seen in eight (36.4%) of the angiomyolipomas and 21 of the hepatocellular carcinomas (84%) (p = 0.001). The sensitivity, specificity, and accuracy of the enhancement pattern for HAML were 63.6% (14/22), 84% (21/25), and 74.5% (35/47), respectively. An early draining vein was seen in 16 (72.7%) angiomyolipomas and two hepatocellular carcinomas (8%) (p < 0.001). The sensitivity, specificity, and accuracy of an early draining vein for detecting HAML was 72.7% (16/22), 92% (23/25), and 83.0% (39/47), respectively. Tumor vessels were noted in 18 (81.8%) angiomyolipomas and six hepatocellular carcinomas (24%) (p < 0.001). The sensitivity, specificity, and accuracy of tumor vessels for HAML were 81.8% (18/22), 76% (19/25), and 78.7% (37/47), respectively. Pseudocapsules were absent in 21 (95.5%) angiomyolipomas as compared with 3 (12%) hepatocellular carcinomas (p < 0.001). The sensitivity, specificity, and accuracy of pseudocapsules for HAML were 95.5% (21/22), 88% (22/25), and 91.5% (43/47), respectively. The ADC of the angiomyolipomas (1.92 ± 0.29 × 10(-3 )mm(2)/s) was significantly higher than that for hepatocellular carcinomas (1.33 ± 0.25 × 10(-3 )mm(2)/s) (p < 0.001). CONCLUSION: The presence of an early draining vein and tumor vessels, the absence of pseudocapsules and a higher ADC in the hypervascular hepatic tumor on the MRI were helpful for the differentiation of hepatic angiomyolipoma from fat-containing hepatocellular carcinoma.


Assuntos
Angiomiolipoma/patologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Meios de Contraste , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética , Feminino , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
13.
Acta Radiol ; 54(8): 909-15, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23817682

RESUMO

BACKGROUND: The low-dose computed tomography (CT) technique has been widely used because it decreases the potential risk of radiation exposure, as well as enabling low-dose CT-guided lung lesion biopsy. However, uncertainties remain regarding diagnostic accuracy, radiation dose, complication rate, and image quality. PURPOSE: To compare the diagnostic accuracy, radiation dose, complication rate, and image quality of lung lesion biopsy between conventional CT-guided and low-dose CT-guided techniques. MATERIAL AND METHODS: A total of 90 patients were prospectively enrolled and randomized into two groups (group A: 120 kv; 200 mA; thickness, 2.0 mm; pitch, 16 mm/rot; n = 44; group B: 120 kv;10 mA; thickness, 2.0 mm; pitch, 23 mm/rot; n = 46). Sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), radiation dose, image quality, and complication rate were compared. All variables between the two groups were analyzed using chi-square and Student's t tests. A P value of < 0.05 was considered statistically significant. RESULTS: The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) for diagnosing lung lesions were 96.88%, 100%, 97.5%, 100%, and 88.89% in group A, respectively. In group B, the values were 96.67%, 100%, 97.5%, 100%, and 90.91%, respectively (P > 0.05). The mean weighted CT dose index (CTDIw) and dose-length product (DLP) were 29.29 ± 3.93 mGy and 211.74 ± 37.89 mGy*cm in group A and 1.55 ± 0.15 mGy and 10.98 ± 1.56 mGy*cm in group B (P < 0.001). Image quality satisfied the need for a coaxial biopsy. Complications in group A and group B were observed in 27.28% and 23.91% of the patients, respectively (P > 0.05). CONCLUSION: Compared to conventional CT-guided biopsies, lung lesion biopsies guided by the low-dose CT biopsy protocol showed dramatically lower CTDIw and DLP levels. In contrast, the diagnostic yield of the procedures did not differ significantly, which is a recommended technique in certain populations.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Doses de Radiação , Radiografia Intervencionista/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Estudos de Viabilidade , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
14.
Methods Mol Biol ; 2698: 361-379, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37682485

RESUMO

Leveraging existing resources in studied species to predict gene functions has the potential to rapidly expand understanding of annotated genes in other, less well-studied, species with assembled genomes. However, orthology is not a reliable predictor for the transcriptional responses of genes to stress. Machine learning methods can quantitatively estimate expression patterns and gene functions using known annotations and collections of features describing each gene. In this chapter, we describe a supervised machine learning framework to predict stress-responsive genes across species using only features derived from nucleotide sequences, using the example of cold stress-responsive genes in different Panicoid grass species.


Assuntos
Aprendizado de Máquina , Aprendizado de Máquina Supervisionado , Resposta ao Choque Frio , Poaceae/genética
15.
Nanomaterials (Basel) ; 13(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36986006

RESUMO

Titanium and its alloys are widely used in high-end manufacturing fields. However, their low high-temperature oxidation resistance has limited their further application. Recently, laser alloying processing has attracted researchers to improve the surface properties of Ti, for which Ni coated graphite system is an excellent prospect due to its outstanding properties and metallurgical bonding between coating and substrate. In this paper, nanoscaled rare earth oxide Nd2O3 addition was added to Ni coated graphite laser alloying materials to research its influence on the microstructure and high-temperature oxidation resistance of the coating. The results proved that nano-Nd2O3 has an outstanding effect on refining coating microstructures, thus the high-temperature oxidation resistance was improved. Furthermore, with the addition of 1. 5 wt.% nano-Nd2O3, more NiO formed in the oxide film, which effectively strengthened the protective effect of the film. After 100 h of 800 °C oxidation, the oxidation weight gain per unit area of the normal coating was 14.571 mg/cm2, while that of the coating with nano-Nd2O3 addition was 6.244 mg/cm2, further proving that the addition of nano-Nd2O3 substantially improved the high-temperature oxidation properties of the coating.

16.
J Interv Med ; 6(4): 145-152, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38312127

RESUMO

Transradial access (TRA) is a safe and comfortable approach and the preferred access for percutaneous coronary intervention. However, TRA is not widely used for peripheral interventions. Currently, there is a lack of data on patient selection, appropriate medical devices, complication prevention, and TRA adoption. Therefore, the Chinese Society of Interventional Oncology of the China Anti-Cancer Association organized nationwide experts to establish a Working Group of China Expert Consensus on TRA in percutaneous peripheral interventions in 2022, and jointly formulated this consensus to better promote the application of TRA in peripheral interventions to guide clinicians on patient selection, technical recommendations, and physician training. This consensus mainly focuses on the current situation, advantages and limitations of TRA in peripheral interventions, anatomical characteristics of the radial artery, patient selection, technical aspects, prevention and management of complications, radiation dose, and learning curve. A consensus was reached through a literature evaluation and by referring to the opinions of the expert group.

17.
Nat Biomed Eng ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38036617

RESUMO

The limited availability of cytokines in solid tumours hinders maintenance of the antitumour activity of chimeric antigen receptor (CAR) T cells. Cytokine receptor signalling pathways in CAR T cells can be activated by transgenic expression or injection of cytokines in the tumour, or by engineering the activation of cognate cytokine receptors. However, these strategies are constrained by toxicity arising from the activation of bystander cells, by the suboptimal biodistribution of the cytokines and by downregulation of the cognate receptor. Here we show that replacement of the extracellular domains of heterodimeric cytokine receptors in T cells with two leucine zipper motifs provides optimal Janus kinase/signal transducer and activator of transcription signalling. Such chimeric cytokine receptors, which can be generated for common γ-chain receptors, interleukin-10 and -12 receptors, enabled T cells to survive cytokine starvation without induction of autonomous cell growth, and augmented the effector function of CAR T cells in vitro in the setting of chronic antigen exposure and in human tumour xenografts in mice. As a modular design, leucine zippers can be used to generate constitutively active cytokine receptors in effector immune cells.

18.
Materials (Basel) ; 15(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36079201

RESUMO

Laser alloying has attracted significant attentions due to the advantages of high processing precision, good controllability and low heat effects on the substrate. However, the complexity of laser alloying requires further attentions on its processing parameters. This study aims at improving the wear resistance of the Ti-6Al-4V substrate by means of laser surface alloying with Ni-coated graphite (G@Ni). The effect of laser scanning speed is explored. The result suggests that the coating has a high surface quality and excellent metallurgical bonding with the substrate. NiTi and NiTi2 have a eutectic microstructure as well as in the TiC ceramic-reinforced phase as dendrites distribute in the γ-Ni matrix of the coatings. At higher scanning speeds, the lower energy density and shorter existence time of the molten pool refines the microstructure of the coating, improving its microhardness. At the scanning speed of 15 mm/s, the coating has the lowest wear weight loss due to its high microhardness and dense structure. This paper explores the influence of scanning speed on the microstructure and properties of the coatings, expanding the application of laser alloying on the surface modification of Ti-6Al-4V alloys.

19.
Diagn Interv Radiol ; 28(4): 376-382, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35950283

RESUMO

PURPOSE This study aimed to compare the radiation dose received by the operator among different patients' positions via transradial access (TRA) or transfemoral access (TFA) during transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). METHODS A total of 120 patients with HCC undergoing TACE for the first time between January and November 2019 were randomized into 4 groups with 30 patients in each group. In group A, patients were placed in the foot-first position with the left upper arm abducted, and TACE was performed via the left radial artery. In group B, patients were placed in the conventional headfirst position with the left hand placed at the left groin, and TACE was performed via the left radial artery. In group C, patients were placed in the conventional head-first position, and TACE was performed via the right radial artery. In group D, patients were placed in the conventional head-first position, and TACE was performed via the right femoral artery. Before each procedure, thermoluminescent dosimeters were taped at 7 different body parts of the operator and the radiation dose was measured and collected after the procedure. The normalized radiation dose was also calculated. Procedural parameters included radiation dose, fluoroscopy time (FT), dose-area product (DAP), and air kerma (AK) were recorded. Patients' demographics, tumor baseline characteristics, radiation dose, and procedural parameters were compared between groups. RESULTS No significant differences were found in patients' demographics, tumor baseline characteristics, as well as in total FT, DAP, and AK. However, significant differences were found in the total radiation dose received by the operator and the doses on the pelvic cavity and the right wrist (P < .05). In group C, the radiation doses received on the pelvic cavity, the right wrist, and the total radiation doses were relatively higher. Significant differences were also found in the normalized radiation doses received by the operator on the thyroid, chest, left wrist, right wrist, and pelvic cavity, and the total normalized doses (all P < .05). Similarly, the radiation doses received by the operator at the aforementioned parts in group C were higher, while those in group A were lower. CONCLUSION No statistically significant differences were observed in the FT, DAP, and AK in TACE via TRA when patients were placed in different positions. However, TACE via the left TRA, with patients in the feet-first position, reduced the radiation dose received by the operator, thereby reducing the radiation risk.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Artéria Femoral , Humanos , Neoplasias Hepáticas/terapia , Posicionamento do Paciente/métodos , Artéria Radial , Doses de Radiação
20.
Front Plant Sci ; 13: 937392, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35873990

RESUMO

The highly esteemed Chinese herb, Dendrobium huoshanense, whose major metabolites are polysaccharides and alkaloids, is on the verge of extinction. The stone planting under the forest (SPUF) and greenhouse planting (GP) of D. huoshanense are two different cultivation methods of pharmaceutical Dendrobium with significantly differences in morphology, metabolites content and composition, and medication efficacy. Here, we conducted proteomics and phosphoproteomics analyses to reveal differences in molecular mechanisms between SPUF and GP. We identified 237 differentially expressed proteins (DEPs) between the two proteomes, and 291 modification sites belonging to 215 phosphoproteins with a phosphorylation level significantly changed (PLSC) were observed. GO, KEGG pathway, protein domain, and cluster analyses revealed that these DEPs were mainly localized in the chloroplast; involved in processes such as posttranslational modification, carbohydrate transport and metabolism, and secondary metabolite biosynthesis; and enriched in pathways mainly including linoleic acid metabolism, plant-pathogen interactions, and phenylpropanoid, cutin, suberin, and wax biosynthesis. PLSC phosphoproteins were mainly located in the chloroplast, and highly enriched in responses to different stresses and signal transduction mechanisms through protein kinase and phosphotransferase activities. Significant differences between SPUF and GP were observed by mapping the DEPs and phosphorylated proteins to photosynthesis and polysaccharide and alkaloid biosynthesis pathways. Phosphorylation characteristics and kinase categories in D. huoshanense were also clarified in this study. We analyzed different molecular mechanisms between SPUF and GP at proteomic and phosphoproteomic levels, providing valuable information for the development and utilization of D. huoshanense.

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