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BACKGROUND: The P-stalk is a conserved and vital structural element of ribosome. The eukaryotic P-stalk exists as a P0-(P1-P2)2 pentameric complex, in which P0 function as a base structure for incorporating the stalk onto 60S pre-ribosome. Prior studies have suggested that P0 genes are indispensable for survival in yeast and animals. However, the functions of P0 genes in plants remain elusive. RESULTS: In the present study, we show that rice has three P0 genes predicted to encode highly conserved proteins OsP0A, OsP0B and OsP0C. All of these P0 proteins were localized both in cytoplasm and nucleus, and all interacted with OsP1. Intriguingly, the transcripts of OsP0A presented more than 90% of the total P0 transcripts. Moreover, knockout of OsP0A led to embryo lethality, while single or double knockout of OsP0B and OsP0C did not show any visible defects in rice. The genomic DNA of OsP0A could well complement the lethal phenotypes of osp0a mutant. Finally, sequence and syntenic analyses revealed that OsP0C evolved from OsP0A, and that duplication of genomic fragment harboring OsP0C further gave birth to OsP0B, and both of these duplication events might happen prior to the differentiation of indica and japonica subspecies in rice ancestor. CONCLUSION: These data suggested that OsP0A functions as the predominant P0 gene, playing an essential role in embryo development in rice. Our findings highlighted the importance of P0 genes in plant development.
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Oryza , Proteínas Ribossômicas , Animais , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Oryza/genética , Oryza/metabolismo , Ribossomos/metabolismo , Saccharomyces cerevisiae/metabolismo , Desenvolvimento EmbrionárioRESUMO
Objective: To analyze the electroencephalogram (EEG) features of anti-N-methyl-D-aspartate receptor encephalitis (anti-NMDARE) and to study the clinical assessment value of the degree of EEG background slowing and the presence of δ brush. Methods: We enrolled 52 patients with anti-NMDARE and collected their clinical data, including age, sex, form of disease onset, status of tumor comorbidity, auxiliary examination findings (cerebrospinal fluid [CSF] anti-methyl-D-aspartate receptor antibody titers, magnetic resonance imaging [MRI] reports, and EEG results), treatment status, and follow-up after discharge. The degree of EEG background abnormality and the presence of δ brush in the EEG of patients with different clinical features were analyzed. Results: Among the 52 patients, 7 (14%) had normal EEG, and 45 (87%), abnormal EEG, including 25 (48%) with mild abnormalities, 11 (21%) with moderate abnormalities, and 9 (17%) with severe abnormalities. δ brush was seen in 6 (12%) patients. At the time of EEG, 32 (62%) patients were in the mild condition group and 20 (38%) patients were in the severe condition group. After 1 year of follow-up, there were 45 (86%) patients in the good prognosis group and 7 (14%) patients in the poor prognosis group. The exacerbation of EEG background abnormalities and the presence of δ brush were indications for an increase in the proportion of patients who were in severe condition, who needed ICU admission, and who had poor prognosis ( P<0.01). The worse the EEG background abnormalities, the higher the proportion of CSF antibody titers>1â¶10 ( P=0.035), and the higher the proportion of patients initiating second-line immunotherapy ( P=0.008). The δ brush was seen a higher proportion in patients with comorbid tumors ( P=0.012). The probability of δ brush presence was higher in the first-time diagnosis cases than that in recurrent cases ( P=0.023). Conclusions: The degree of EEG slowing and the presence of δ brush have shown consistent performance in assessing patients' condition and predicting prognosis. The slower the EEG, the more severe the disease, and the worse the prognosis. The presence of δ brush indicates severe disease and poor prognosis. EEG slowing is correlated with the immune status of patients with anti-NMDARE. The slower the EEG, the more severe the immune abnormalities. In clinical practice, patient EEG should be under dynamic monitoring in order to evaluate the effect of immunotherapy. If EEG slowing is not improved, enhanced immunotherapy should be considered as early as possible. The δ brush is seen at a higher proportion in patients with comorbid tumors. Therefore, active efforts should be made to screen for tumors when δ brush is present.
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Encefalite Antirreceptor de N-Metil-D-Aspartato , Humanos , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico , Encefalite Antirreceptor de N-Metil-D-Aspartato/líquido cefalorraquidiano , Eletroencefalografia/métodos , HospitalizaçãoRESUMO
Carotenoid cleavage dioxygenases (CCDs) drive carotenoid catabolism to produce various apocarotenoids and immediate derivatives with particular developmental, ecological, and agricultural importance. How CCD genes evolved with species diversification and the resulting functional novelties in cereal crops have remained largely elusive. We constructed a unified four-clade phylogenetic tree of CCDs, revealing a previously unanchored basal clade CCD10 CCD10 underwent highly dynamic duplication or loss events, even in the grass family. Different from cleavage sites of CCD8 and ZAXINONE SYNTHASE (ZAS), maize (Zea mays) ZmCCD10a cleaved differentially structured carotenoids at 5, 6 (5', 6') and 9, 10 (9', 10') positions, generating C8 (6-methyl-5-hepten-2-one) and C13 (geranylacetone, α-ionone, and ß-ionone) apocarotenoids in Escherichia coli Localized in plastids, ZmCCD10a cleaved neoxanthin, violaxanthin, antheraxathin, lutein, zeaxanthin, and ß-carotene in planta, corroborating functional divergence of ZmCCD10a and ZAS. ZmCCD10a expression was dramatically stimulated in maize and teosinte (Z. mays ssp. parviglumis, Z. mays ssp. huehuetenangensis, Zea luxurians, and Zea diploperennis) roots by phosphate (Pi) limitation. ZmCCD10a silencing favored phosphorus retention in the root and reduced phosphorus and biomass accumulation in the shoot under low Pi. Overexpression of ZmCCD10a in Arabidopsis (Arabidopsis thaliana) enhanced plant tolerance to Pi limitation by preferential phosphorus allocation to the shoot. Thus, ZmCCD10a encodes a unique CCD facilitating plant tolerance to Pi limitation. Additionally, ZmCCD10a silencing and overexpression led to coherent alterations in expression of PHOSPHATE STARVATION RESPONSE REGULATOR 1 (PHR1) and Pi transporters, and cis-regulation of ZmCCD10a expression by ZmPHR1;1 and ZmPHR1;2 implies a probable ZmCCD10a-involved regulatory pathway that adjusts Pi allocation.
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Carotenoides/metabolismo , Dioxigenases/metabolismo , Fosfatos/metabolismo , Proteínas de Plantas/metabolismo , Arabidopsis/metabolismo , Norisoprenoides/metabolismo , Terpenos/metabolismo , Xantofilas/metabolismo , Zea mays/metabolismo , beta Caroteno/metabolismoRESUMO
Pollen development is critical to the reproductive success of flowering plants, but how it is regulated is not well understood. Here, we isolated two allelic male-sterile mutants of OsMYB80 and investigated how OsMYB80 regulates male fertility in rice. OsMYB80 was barely expressed in tissues other than anthers, where it initiated the expression during meiosis, reached the peak at the tetrad-releasing stage and then quickly declined afterward. The osmyb80 mutants exhibited premature tapetum cell death, lack of Ubisch bodies, no exine and microspore degeneration. To understand how OsMYB80 regulates anther development, RNA-seq analysis was conducted to identify genes differentially regulated by OsMYB80 in rice anthers. In addition, DNA affinity purification sequencing (DAP-seq) analysis was performed to identify DNA fragments interacting with OsMYB80 in vitro. Overlap of the genes identified by RNA-seq and DAP-seq revealed 188 genes that were differentially regulated by OsMYB80 and also carried an OsMYB80-interacting DNA element in the promoter. Ten of these promoter elements were randomly selected for gel shift assay and yeast one-hybrid assay, and all showed OsMYB80 binding. The 10 promoters also showed OsMYB80-dependent induction when co-expressed in rice protoplast. Functional annotation of the 188 genes suggested that OsMYB80 regulates male fertility by directly targeting multiple biological processes. The identification of these genes significantly enriched the gene networks governing anther development and provided much new information for the understanding of pollen development and male fertility.
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Oryza/fisiologia , Proteínas de Plantas/metabolismo , Pólen/crescimento & desenvolvimento , Pólen/fisiologia , Transdução de Sinais , Sítios de Ligação , Fertilidade , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Mutação/genética , Motivos de Nucleotídeos/genética , Oryza/genética , Oryza/ultraestrutura , Infertilidade das Plantas/genética , Proteínas de Plantas/genética , Pólen/genética , Pólen/ultraestrutura , Regiões Promotoras Genéticas , Ligação Proteica , Reprodutibilidade dos TestesRESUMO
The relationship between the chemical forms of Cu2+ and Cd2+ adsorbed on the roots of different wheat cultivars and their phytotoxic effects on the plants were investigated. The wheat varieties Dunmaiwang (DMW), Tekang 6 (TK6), Zhongmai895 (ZM895), and Chaojixiaomai (AK68) were used. The zeta potentials of wheat roots, measured by the streaming potential method, were used to characterize root charge properties. Results indicated that the changes in zeta potential at pH 4.01-6.61 were 14.7, 15.53, 13.01, and 12.06 mV for ZM895, AK68, DMW, and TK6, respectively. The negative charge and functional groups on ZM895 and AK68 roots were greater than on DMW and TK6 roots, which led to more exchangeable and complexed Cu2+ and Cd2+ on ZM895 and AK68 roots and increased Cu2+ and Cd2+ toxicity compared to DMW and TK6. Coexisting cations, such as Ca2+, Mg2+, K+, and NH4+, alleviated Cu2+ and Cd2+ toxicity to wheat roots through competition for adsorption sites on the roots, which decreased exchangeable and complexed Cu2+ and Cd2+ on wheat roots. The Ca2+ and Mg2+ were most effective in alleviating heavy metal toxicity and they decreased exchangeable Cu2+ on AK68 roots by 39.14% and 47.82%, and exchangeable Cd2+ by 8.51% and 28.23%, respectively.
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Cádmio/toxicidade , Cobre/toxicidade , Poluentes do Solo/toxicidade , Triticum/efeitos dos fármacos , Adsorção , Cádmio/química , Cádmio/farmacocinética , Cátions , Cobre/química , Cobre/farmacocinética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , Poluentes do Solo/química , Poluentes do Solo/farmacocinética , Triticum/metabolismo , Triticum/fisiologiaRESUMO
Modulation of dystrophin pre-mRNA splicing is an attractive strategy to ameliorate the severe phenotype of Duchenne muscular dystrophy (DMD), although this requires a better understanding of the mechanism of splicing regulation. Aberrant splicing caused by gene mutations provides a good model to study splicing regulatory cis-elements and binding proteins. In this study, we identified skipping of in-frame exon 25 induced by a nonsense mutation (NM_004006.2:c.3340A > T;p.Lys1114*) in the DMD gene. Site-directed mutagenesis study in minigenes suggested that c.3340A > T converts an exonic splicing enhancer sequence (ESE) to a silencer element (ESS). Indeed, RNA pull-down and functional study provided evidence that c.3340A > T abolishes the binding of the splicing enhancer protein Tra2ß and promotes interactions with the repressor proteins hnRNP A1, hnRNP A2, and hnRNP H. By carefully analyzing the sequence motif encompassing the mutation site, we concluded that the skipping of exon 25 was due to disruption of a Tra2ß-dependent ESE and the creation of a new ESS associated with hnRNP A1 and hnRNP A2, which in turn increased the recruitment of hnRNP H to a nearby binding site. Finally, we demonstrated that c.3340A > T impairs the splicing of upstream intron 24 in a splicing minigene assay. In addition, we showed that the correct splicing of exon 25 is finely regulated by multiple splicing regulators that function in opposite directions by binding to closely located ESE and ESS. Our results clarify the detailed molecular mechanism of exon skipping induced by the nonsense mutation c.3340A > T and also provide information on exon 25 splicing.
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Distrofina/genética , Elementos Facilitadores Genéticos , Éxons , Distrofia Muscular de Duchenne/genética , Mutação de Sentido Incorreto , Splicing de RNA , Elementos Silenciadores Transcricionais , Adolescente , Regulação da Expressão Gênica , Humanos , Masculino , Distrofia Muscular de Duchenne/patologiaRESUMO
The continuous production of low molecular weight (LMW) organic acids by plants and microorganisms coupled with the continuous presence of extracellular polymeric substances (EPS) in soils is a guarantee that the mobility of heavy metals in soils will be controlled. The effects of citrate, oxalate, and EPS on the adsorption of Pb by an acidic Ultisol were studied both as a function of pH and ionic strength. Electrokinetic potential measurements were also employed to observe to what extent each ligand affected the surface charge property of the Ultisol. All the ligands shifted the zeta potential of the Ultisol to the negative direction, implying that the surface charge of the soil became more negative. The effect on the zeta potential of the soil was observed in the order of oxalate Ë citrate Ë EPS. The quantity of Pb adsorbed at each pH (3.0-7.0) reflected the corresponding change in the zeta potential as induced by each ligand. The presence of the ligands shifted the isoelectric point of the Ultisol from 4.8 to 3.2 for the EPS system and below 3.0 for the citrate and oxalate systems. More Pb was adsorbed in the presence of oxalate than in the presence of citrate and EPS. The two most outstanding mechanisms that governed the adsorption of Pb by the Ultisol were (1) electrostatic attraction which was supported by the increase in negative zeta potential of the Ultisol and, (2) complexation which was supported by the lesser proportion of Pb adsorbed in the citrate system at higher pH and also by the spectroscopic data for EPS. The combination EPS + citrate + oxalate was more effective in enhancing the adsorption of Pb than the combination EPS + oxalate and EPS + citrate.
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Ácido Cítrico/química , Matriz Extracelular de Substâncias Poliméricas , Chumbo/química , Oxalatos/química , Pseudomonas fluorescens , Poluentes do Solo/química , Solo/química , Adsorção , Concentração de Íons de Hidrogênio , Concentração Osmolar , Propriedades de SuperfícieRESUMO
Pollen germination is an essential step towards successful pollination during maize reproduction. How low niutrogen (N) affects pollen germination remains an interesting biological question to be addressed. We found that only low N resulted in a significantly lower germination rate of pollen grains after 4 weeks of low N, phosphorus or potassium treatment in maize production. Importantly, cytological analysis showed 7-fold more micronuclei in male meiocytes under the low N treatment than in the control, indicating that the lower germination rate of pollen grains was partially due to numerous chromosome loss events resulting from preceding meiosis. The appearance of 10 bivalents in the control and low N cells at diakinesis suggested that chromosome pairing and recombination in meiosis I was not affected by low N. Further gene expression analysis revealed dramatic down-regulation of Nuclear Division Cycle 80 (Ndc80) and Regulator of Chromosome Condensation 1 (Rcc1-1) expression and up-regulation of Cell Division Cycle 20 (Cdc20-1) expression, although no significant difference in the expression level of kinetochore foundation proteins Centromeric Histone H3 (Cenh3) and Centromere Protein C (Cenpc) and cohesion regulators Recombination 8 (Rec8) and Shugoshin (Sgo1) was observed. Aberrant modulation of three key meiotic regulators presumably resulted in a high likelihood of erroneous chromosome segregation, as testified by pronounced lagging chromosomes at anaphase I or cell cycle disruption at meiosis II. Thus, we proposed a cytogenetic mechanism whereby low N affects male meiosis and causes a higher chromosome loss frequency and eventually a lower germination rate of pollen grains in a staple crop plant.
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Germinação/fisiologia , Meiose/fisiologia , Nitrogênio/metabolismo , Zea mays/metabolismo , Zea mays/fisiologia , Segregação de Cromossomos/genética , Segregação de Cromossomos/fisiologia , Germinação/genética , Meiose/genética , Nitrogênio/deficiência , Pólen/genética , Pólen/metabolismo , Pólen/fisiologia , Zea mays/genéticaRESUMO
MAIN CONCLUSION: ZmCCD7/ZpCCD7 encodes a carotenoid cleavage dioxygenase that may mediate strigolactone biosynthesis highly responsive to phosphorus deficiency and undergoes negative selection over domestication from Zea ssp. parviglumis to Zea mays. Carotenoid cleavage dioxygenase 7 (CCD7) functions to suppress shoot branching by controlling strigolactone biosynthesis. However, little is known about CCD7 and its functions in maize and its ancestor (Zea ssp. parviglumis) with numerous shoot branches. We found that ZmCCD7 and ZpCCD7 had the same coding sequence, indicating negative selection of the CCD7 gene over domestication from Zea ssp. parviglumis to Zea mays. CCD7 expression was highly responsive to phosphorus deficiency in both species, especially in the meristematic zone and the pericycle of the elongation zone of maize roots. Notably, the crown root had the strongest ZmCCD7 expression in the meristematic zone under phosphorus limitation. Transient expression of GFP tagged ZmCCD7/ZpCCD7 in maize protoplasts indicated their localization in the plastid. Further, ZmCCD7/ZpCCD7 efficiently catalyzed metabolism of six different linear and cyclic carotenoids in E. coli, and generated ß-ionone by cleaving ß-carotene at the 9,10 (9',10') position. Together with suppression of shoot branching in the max3 mutant by transformation of ZmCCD7/ZpCCD7, our work suggested that ZmCCD7/ZpCCD7 encodes a carotenoid cleavage dioxygenase mediating strigolactone biosynthesis in maize and its ancestor.
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Carotenoides/metabolismo , Dioxigenases/fisiologia , Proteínas de Plantas/fisiologia , Zea mays/crescimento & desenvolvimento , Vias Biossintéticas/genética , Clonagem Molecular , Dioxigenases/genética , Dioxigenases/metabolismo , Regulação da Expressão Gênica de Plantas , Lactonas/metabolismo , Fósforo/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Zea mays/genética , Zea mays/metabolismoRESUMO
MAIN CONCLUSION: ZD958 was the most low-N-efficient line among five maize and two teosinte lines. Zea parviglumis and Zea diploperennis were insensitive to N limitation. Maize and teosinte genetically and evolutionarily diverged in gene regulation. GDH2, ASN2, and T4 were consistently down-regulated across seven lines. Maternal asymmetric inheritance and heterosis vigor made ZD958 low-N-efficient. Nitrogen (N) deficiency remains a serious limiting factor for maize production in many developing countries. It is particularly important to better understand how hybrid maize responds to N limitation. ZD958, a dominant high-yield hybrid in North China, was comparatively analyzed with four other maize and two teosinte lines at physiological and transcriptional levels. ZD958 was the most low-N-efficient line among five maize and two teosinte lines due to its largest biomass accumulation at a lowest N concentration under N limitation; while Zea parviglumis and Zea diploperennis had large root systems and were insensitive to N limitation. In anti-parallel with down-regulation of N metabolic genes in the ZD958 root, carbon allocation towards the root was enhanced for the significant increase in the root length. Variations in expression patterns of ten genes mediating N uptake, transport, and metabolism indicated large genetic and evolutionary divergence among seven lines under N limitation. Notably, GDH2, ASN2, and VAAT5 were consistently down-regulated under N limitation across these maize and teosinte lines, suggesting essential evolutionary conservation of gene regulation in response to N limitation and providing molecular markers for N nutritional diagnosis. Asymmetric inheritance, mostly from its maternal donor Z58, and heterosis vigor made ZD958 low-N-efficient at the seedling stage. The superior traits in crown roots in ZD958 may be derived from its paternal donor Chang7-2. Thus, Z58, Chang7-2, and two wild maize lines (Z. parviglumis and Z. diploperennis) provide valuable germplasms for N-efficient and large-root maize breeding.
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Nitrogênio/metabolismo , Zea mays/metabolismo , Genes de Plantas , Transcrição Gênica , Zea mays/genética , Zea mays/crescimento & desenvolvimentoRESUMO
Coordinated functioning of the cob and florets of the maize ear confers grain yield. The cob is critical for carbon partitioning and assimilated nitrogen (N) supply for grain development. However, molecular recognition of the cob and peripheral florets, characterization of genes mediating translocation of N assimilates, and responses of these two tissues to low N (LN) remain elusive. Transcriptional profiling of the ear of a maize hybrid at silking in the field revealed 1864 differentially expressed genes between the cob and florets, with 1314 genes up-regulated in the cob and 550 genes up-regulated in florets. The cob was characterized by striking enrichment of genes that are involved in carbon/N transport and metabolism, consistent with the physiological role of the cob in carbon/N storage and transfer during ear development. The florets were characterized by enrichment of hormone signalling components and development related genes. We next examined the response of the cob and florets to LN stress. LN caused differential expression of 588 genes in the cob and only 195 genes in the florets, indicating that the cob dominated the response of the ear to LN at the transcriptional level. LN caused comprehensive alterations such as carbon/N metabolism or partitioning, hormone signalling and protein phosphorylation in terms of gene expression in the cob and/or florets. Fourteen genes responsive specifically to LN provided potential molecular markers for N-efficient maize breeding. We further functionally characterized two newly identified broad-spectrum amino acid transporters, ZmAAP4 and ZmVAAT3, that showed distinct expression patterns in the cob and florets and potentially important roles in amino-N mobilization in the ear. While both proteins could transport various amino acids into yeast or Arabidopsis cells, ZmAAP4 appeared to have higher efficiencies than ZmVAAT3 in transporting seven out of 22 examined amino acids.
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Sistemas de Transporte de Aminoácidos/genética , Regulação da Expressão Gênica de Plantas , Nitrogênio/metabolismo , Proteínas de Plantas/genética , Zea mays/crescimento & desenvolvimento , Zea mays/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Topos Floridos/metabolismo , Flores/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Plantas/metabolismo , Transcriptoma , Zea mays/metabolismoRESUMO
PURPOSE: Abnormal tissue detection is a prerequisite for medical image analysis and computer-aided diagnosis and treatment. The use of neural networks (CNN) to achieve accurate detection of intestinal polyps is beneficial to the early diagnosis and treatment of colorectal cancer. Currently, image detection models using multi-scale feature processing perform well in polyp detection. However, these methods do not fully consider the misalignment of information in the process of feature scale change, resulting in the loss of fine-grained features, and eventually cause the missed and false detection of targets. METHOD: To solve this problem, a texture-aware and fine-grained feature compensated polyp detection network (TFCNet) is proposed in this paper. Firstly, design Texture Awareness Module (TAM) to excavate the rich texture information from the low-level layers and utilize high-level semantic information for background suppression, thereby capturing purer fine-grained features. Secondly, the Texture Feature Enhancement Module (TFEM) is designed to enhance the low-level texture information in TAM, and the enhanced texture features were fused with the high-level features. By making full use of the low-level texture features and multi-scale context information, the semantic consistency and integrity of the features were ensured. Finally, the Residual Pyramid Splittable Attention Module (RPSA) is designed to balance the loss of channel information caused by skip connections, and further improve the detection performance of the network. RESULTS: Experimental results on 4 datasets demonstrate that the TFCNet network outperforms existing methods. Particularly, on the large dataset PolypSets, the mAP@0.5-0.95 has been improved to 88.9%. On the small datasets CVC-ClinicDB and Kvasir, the mAP@0.5-0.95 is increased by 2% and 1.6%, respectively, compared to the baseline, showcasing a significant superiority over competing methods.
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Diagnóstico por Computador , Redes Neurais de Computação , Semântica , Processamento de Imagem Assistida por ComputadorRESUMO
PURPOSE: Accurately locating and analysing surgical instruments in laparoscopic surgical videos can assist doctors in postoperative quality assessment. This can provide patients with more scientific and rational solutions for healing surgical complications. Therefore, we propose an end-to-end algorithm for the detection of surgical instruments. METHODS: Dual-Branched Head (DBH) and Overall Intersection over Union Loss (OIoU Loss) are introduced to solve the problem of inaccurate surgical instrument detection, both in terms of localization and classification. An effective method (DBHYOLO) for the detection for laparoscopic surgery in complex scenarios is proposed. This study manually annotates a new laparoscopic gastric cancer resection surgical instrument location dataset LGIL, which provides a better validation platform for surgical instrument detection methods. RESULTS: The proposed method's performance was tested using the m2cai16-tool-locations, LGIL, and Onyeogulu datasets. The mean Average Precision (mAP) values obtained were 96.8%, 95.6%, and 98.4%, respectively, which were higher than the other classical models compared. The improved model is more effective than the benchmark network in distinguishing between surgical instrument classes with high similarity and avoiding too many missed detection cases. CONCLUSIONS: In this paper, the problem of inaccurate detection of surgical instruments is addressed from two different perspectives: classification and localization. And the experimental results on three representative datasets verify the performance of DBH-YOLO. It is shown that this method has a good generalization capability.
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Tobacco (Nicotiana tabacum L.) is an important industrial crop, which is sensitive to chilling stress. Tobacco seedlings that have been subjected to chilling stress readily flower early, which seriously affects the yield and quality of their leaves. Currently, there has been progress in elucidating the molecular mechanisms by which tobacco responds to chilling stress. However, little is known about the phosphorylation that is mediated by chilling. In this study, the transcriptome, proteome and phosphoproteome were analyzed to elucidate the mechanisms of the responses of tobacco shoot and root to chilling stress (4 °C for 24 h). A total of 6,113 differentially expressed genes (DEGs), 153 differentially expressed proteins (DEPs) and 345 differential phosphopeptides were identified in the shoot, and the corresponding numbers in the root were 6,394, 212 and 404, respectively. This study showed that the tobacco seedlings to 24 h of chilling stress primarily responded to this phenomenon by altering their levels of phosphopeptide abundance. Kyoto Encyclopedia of Genes and Genomes analyses revealed that starch and sucrose metabolism and endocytosis were the common pathways in the shoot and root at these levels. In addition, the differential phosphopeptide corresponding proteins were also significantly enriched in the pathways of photosynthesis-antenna proteins and carbon fixation in photosynthetic organisms in the shoot and arginine and proline metabolism, peroxisome and RNA transport in the root. These results suggest that phosphoproteins in these pathways play important roles in the response to chilling stress. Moreover, kinases and transcription factors (TFs) that respond to chilling at the levels of phosphorylation are also crucial for resistance to chilling in tobacco seedlings. The phosphorylation or dephosphorylation of kinases, such as CDPKs and RLKs; and TFs, including VIP1-like, ABI5-like protein 2, TCP7-like, WRKY 6-like, MYC2-like and CAMTA7 among others, may play essential roles in the transduction of tobacco chilling signal and the transcriptional regulation of the genes that respond to chilling stress. Taken together, these findings provide new insights into the molecular mechanisms and regulatory networks of the responses of tobacco to chilling stress.
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OBJECTIVE: The aim of this study was to construct a multicompartment synchronous rotating bioreactor (MCSRB) for batch-production of homogenized adipose-derived stem cell (ADSC) microspheres and treat neurogenic erectile dysfunction (ED). METHODS: Firstly, an MCSRB was constructed using a centrifugal device and hinged trays. Secondly, influence factors (density, rotational speed) on the formation of ADSC-spheroids were explored. Finally, a neurogenic ED model was established to verify the effectiveness and safety of ADSC-spheroids for ED treatment. RESULTS: An MCSRB promoted ADSCs to gather microspheres, most of which were 90-130 µm in diameter. Supernatant from three-dimensional culture led to a significant increase in cytokine expression in ADSCs and migration rate in human umbilical vein endothelial cells (HUVECs) compared to control groups. The erectile function and pathological changes of the penis were improved in the ADSC-spheroids treatment group compared to the traditional ADSCs treatment group (p < 0.01). CONCLUSION: Efficient, batch, controlled and homogenized production of ADSC stem cell microspheres, and effective improvement of erectile dysfunction in neurogenic rats can be achieved using the MCSRB device.
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The Nicotiana tabacum L. plant, a medicinal resource, holds significant potential for benefiting human health, as evidenced by its use in Native American and ancient Chinese cultures. Modern medical and pharmaceutical studies have investigated that the abundant and distinctive function metabolites in tobacco including nicotine, solanesol, cembranoid diterpenes, essential oil, seed oil and other tobacco extracts, avoiding the toxic components of smoke, mainly have the anti-oxidation, anti-lipid production, pro-lipid oxidation, pro-insulin sensitivity, anti-inflammation, anti-apoptosis and antimicrobial activities. They showed potential pharmaceutical value mainly as supplements or substitutes for treating neurodegenerative diseases including Alzheimer's and Parkinson's disease, inflammatory diseases including colitis, arthritis, sepsis, multiple sclerosis, and myocarditis, and metabolic syndrome including Obesity and fatty liver. This review comprehensively presents the research status and the molecular mechanisms of tobacco and its metabolites basing on almost all the English and Chinese literature in recent 20 years in the field of medicine and pharmacology. This review serves as a foundation for future research on the medicinal potential of tobacco plants.
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Heat stress is a prevalent factor that significantly damages crops, especially with the ongoing global warming and increasing frequency of extreme weather events. Tobacco is particularly sensitive to temperature fluctuations, experiencing reduced yield and quality under high temperatures. However, the underlying molecular mechanisms of heat resistance in tobacco remain poorly understood. This study comprehensively analyzed biochemical, transcriptomic, and metabolomic responses to heat stress on the root and shoot of the tobacco cultivar K326 compared to control conditions. Heat stress significantly increased the activities of antioxidant enzymes (CAT, POD, and SOD) and levels of osmotic mediators (soluble sugars, sucrose, and proline) in the shoot. Furthermore, transcriptome analysis identified 13,176 differentially expressed genes (DEGs) in the root (6,129 up-regulated and 7,047 down-regulated) and 12,283 DEGs (6,621 up-regulated and 5,662 down-regulated) in the shoot. The root had 24 enriched KEGG pathways, including phenylpropanoid metabolism, while the shoot had 32 significant pathways, such as galactose metabolism and MAPK signaling. The metabolomic data identified 647 metabolites in the root and 932 in the shoot, with carbohydrates and amino acids being the main categories. The root had 116 differentially abundant metabolites (DAMs) (107 up-regulated and 9 down-regulated), and the shoot contained 256 DAMs (251 up-regulated and 5 down-regulated). Joint transcriptome and metabolome analysis showed that galactose metabolism and starch and sucrose metabolism were co-enriched in both tissues. In contrast, amino sugar and nucleotide sugar metabolism was enriched in the root, and purine metabolism in the shoot. The purine metabolic pathway in the shoot can modulate the expression of MYB transcription factors by influencing ABA synthesis and signaling, thereby controlling the accumulation of HSPs, raffinose, sucrose, and trehalose to enhance heat tolerance. Furthermore, NtMYB78, an MYB transcription factor, enhances tolerance for heat stress in tobacco. This research offers a foundational framework for investigating and implementing heat-resistant genes and metabolic pathways in the root and shoot of tobacco seedlings.
RESUMO
Axillary bud is an important aspect of plant morphology, contributing to the final tobacco yield. However, the mechanisms of axillary bud development in tobacco remain largely unknown. To investigate this aspect of tobacco biology, the metabolome and proteome of the axillary buds before and after topping were compared. A total of 569 metabolites were differentially abundant before and 1, 3, and 5 days after topping. KEGG analyses further revealed that the axillary bud was characterized by a striking enrichment of metabolites involved in flavonoid metabolism, suggesting a strong flavonoid biosynthesis activity in the tobacco axillary bud after topping. Additionally, 9035 differentially expressed proteins (DEPs) were identified before and 1, 3, and 5 days after topping. Subsequent GO and KEGG analyses revealed that the DEPs in the axillary bud were enriched in oxidative stress, hormone signal transduction, MAPK signaling pathway, and starch and sucrose metabolism. The integrated proteome and metabolome analysis revealed that the indole-3-acetic acid (IAA) alteration in buds control dormancy release and sustained growth of axillary bud by regulating proteins involved in carbohydrate metabolism, amino acid metabolism, and lipid metabolism. Notably, the proteins related to reactive oxygen species (ROS) scavenging and flavonoid biosynthesis were strongly negatively correlated with IAA content. These findings shed light on a critical role of IAA alteration in regulating axillary bud outgrowth, and implied a potential crosstalk among IAA alteration, ROS homeostasis, and flavonoid biosynthesis in tobacco axillary bud under topping stress, which could improve our understanding of the IAA alteration in axillary bud as an important regulator of axillary bud development.
Assuntos
Ácidos Indolacéticos , Metaboloma , Nicotiana , Proteínas de Plantas , Proteoma , Ácidos Indolacéticos/metabolismo , Nicotiana/metabolismo , Nicotiana/crescimento & desenvolvimento , Proteoma/metabolismo , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Flavonoides/metabolismo , Flores/metabolismo , Flores/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/metabolismoRESUMO
Objective: To evaluate the current status of Chinese public's knowledge, attitudes, practices (KAP) and self-efficacy regarding cardiopulmonary resuscitation (CPR), and to analyze the factors that influence KAP and self-efficacy. Methods: An online cross-sectional survey was conducted from February to June 2022 in Mainland China via a self-designed self-filled questionnaire. Potential participants were recruited through WeChat by convenience sampling and snowball sampling methods. Descriptive and quantitative analyses were used for statistical analysis. Results: The survey included 4,450 participants from 31 provinces, autonomous regions, or municipalities across Mainland China, aged 18 or above. The public's average understanding (clear and very clear) of the knowledge regarding CPR was 67.4% (3,000/4,450), with an average proportion of positive attitudes at 96.8% (4,308/4,450). In practice, the average proportion of good practices was 92.8% (4,130/4,450), while the percentage of good self-efficacy averaged at 58.9% (2,621/4,450), only 42.4% (1,885/4,450) of the participants had confidence in the correct use of automated external defibrillator (AED). Pearson correlation analysis showed a significantly positive correlation among knowledge, attitude, practice, and self-efficacy (p < 0.01). Multiple linear regression analysis revealed that several factors have a significant influence on the public's CPR KAP and self-efficacy, including ever having received CPR training (p < 0.001), hearing about AED (p < 0.001), performing CPR on others (p < 0.001), hearing about CPR (p < 0.001), occupation (p < 0.001), personal health status (p < 0.001), education level (p < 0.001), gender (p < 0.001), and encountering someone in need of CPR (p = 0.021). Conclusion: The Chinese public demonstrates good knowledge of CPR, positive attitude, and high willingness to perform CPR. However, there is still room for improvement in the mastery of some professional knowledge points related to CPR and AED. It should be noted that knowledge, attitude, practice, and self-efficacy are interrelated and influence each other. Factors such as prior CPR training, hearing about AED, having performed CPR before, hearing about CPR, occupation, personal health status, education level, gender, and having encountered someone in need of CPR have a significant impact on the public's KAP and self-efficacy.
Assuntos
Reanimação Cardiopulmonar , Humanos , Reanimação Cardiopulmonar/educação , Reanimação Cardiopulmonar/métodos , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Autoeficácia , ChinaRESUMO
Catheter-associated urinary tract infection (CAUTI) is a common clinical problem, especially during long-term catheterization, causing additional pain to patients. The development of novel antimicrobial coatings is needed to prolong the service life of catheters and reduce the incidence of CAUTIs. Herein, we designed an antimicrobial catheter coated with a piezoelectric zinc oxide nanoparticles (ZnO NPs)-incorporated polyvinylidene difluoride-hexafluoropropylene (ZnO-PVDF-HFP) membrane. ZnO-PVDF-HFP could be stably coated onto silicone catheters simply by a one-step solution film-forming method, very convenient for industrial production. In vitro, it was demonstrated that ZnO-PVDF-HFP coating could significantly inhibit bacterial growth and the formation of bacterial biofilm under ultrasound-mediated mechanical stimulation even after 4 weeks. Importantly, the on and off of antimicrobial activity as well as the strenth of antibacterial property could be controlled in an adaptive manner via ultrasound. In a rabbit model, the ZnO-PVDF-HFP-coated catheter significantly reduced the incidence CAUTIs compared with clinically-commonly used catheters under assistance of ultrasonication, and no side effect was detected. Collectively, the study provided a novel antibacterial catheter to prevent the occurrence of CAUTIs, whose antibacterial activity could be controlled in on-demand manner, adaptive to infection situation and promising in clinical application.