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1.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(4): 337-342, 2024 Apr 15.
Artigo em Chinês | MEDLINE | ID: mdl-38660896

RESUMO

OBJECTIVES: To investigate the effects of different angles of pulmonary surfactant (PS) administration on the incidence of bronchopulmonary dysplasia and intracranial hemorrhage in preterm infants. METHODS: A prospective study was conducted on 146 preterm infants (gestational age <32 weeks) admitted to the Department of Neonatology, Provincial Hospital Affiliated to Anhui Medical University from January 2019 to May 2023. The infants were randomly assigned to different angles for injection of pulmonary surfactant groups: 0° group (34 cases), 30° group (36 cases), 45° group (38 cases), and 60° group (38 cases). Clinical indicators and outcomes were compared among the groups. RESULTS: The oxygenation index was lower in the 60° group compared with the other three groups, with shorter invasive ventilation time and oxygen use time, and a lower incidence of bronchopulmonary dysplasia than the other three groups (P<0.05). The incidence of intracranial hemorrhage was lower in the 60° group compared to the 0° group (P<0.05). The cure rate in the 60° group was higher than that in the 0° group and the 30° group (P<0.05). CONCLUSIONS: The clinical efficacy of injection of pulmonary surfactant at a 60° angle is higher than other angles, reducing the incidence of intracranial hemorrhage and bronchopulmonary dysplasia in preterm infants.


Assuntos
Displasia Broncopulmonar , Recém-Nascido Prematuro , Hemorragias Intracranianas , Surfactantes Pulmonares , Humanos , Surfactantes Pulmonares/administração & dosagem , Recém-Nascido , Estudos Prospectivos , Displasia Broncopulmonar/prevenção & controle , Displasia Broncopulmonar/tratamento farmacológico , Displasia Broncopulmonar/etiologia , Masculino , Feminino , Hemorragias Intracranianas/prevenção & controle , Hemorragias Intracranianas/induzido quimicamente
2.
Sensors (Basel) ; 24(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38339725

RESUMO

Visual Simultaneous Localization and Mapping (VSLAM) estimates the robot's pose in three-dimensional space by analyzing the depth variations of inter-frame feature points. Inter-frame feature point mismatches can lead to tracking failure, impacting the accuracy of the mobile robot's self-localization and mapping. This paper proposes a method for removing mismatches of image features in dynamic scenes in visual SLAM. First, the Grid-based Motion Statistics (GMS) method was introduced for fast coarse screening of mismatched image features. Second, an Adaptive Error Threshold RANSAC (ATRANSAC) method, determined by the internal matching rate, was proposed to improve the accuracy of removing mismatched image features in dynamic and static scenes. Third, the GMS-ATRANSAC method was tested for removing mismatched image features, and experimental results showed that GMS-ATRANSAC can remove mismatches of image features on moving objects. It achieved an average error reduction of 29.4% and 32.9% compared to RANSAC and GMS-RANSAC, with a corresponding reduction in error variance of 63.9% and 58.0%, respectively. The processing time was reduced by 78.3% and 38%, respectively. Finally, the effectiveness of inter-frame feature mismatch removal in the initialization thread of ORB-SLAM2 and the tracking thread of ORB-SLAM3 was verified for the proposed algorithm.

3.
Int J Mol Sci ; 24(18)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37762001

RESUMO

Kiwifruit is a perennial fruit tree with high nutritional and economic value; however, various pathogen stresses have resulted in reductions in its yield and quality. Pentatricopeptide repeat proteins (PPRs), characterized by tandem repetitions of 35 amino acid motifs, play roles in RNA editing, mRNA stability, and splicing. They may also regulate plant development and growth. Nevertheless, the roles of PPRs in plant development and disease resistance remain unclear. In this study, we focused on the roles of PPRs in the fruit development and pathogen stress of kiwifruit and conducted a series of analyses of the PPR gene family in two representative kiwifruit species (Actinidia chinensis (Ach) and Actinidia eriantha (Ace)) with markedly different degrees of disease resistance. A total of 497 and 499 PPRs were identified in Ach and Ace, respectively. All the kiwifruit PPRs could be phylogenetically divided into four subfamilies. There were about 40.68% PPRs predicted to be localized to mitochondria or chloroplasts. A synteny analysis showed that the expansion of the kiwifruit PPRs mainly originated from segmental duplication. Based on RNA-seq data from the fruit over 12 periods of development and maturity, a weighted correlation network analysis suggested that two PPRs, Actinidia20495.t1 and Actinidia15159.t1, may be involved in fruit development and maturation. In addition, we observed different responses with respect to the expression of PPRs and RNA editing between resistant and susceptible kiwifruits following infection with pathogenic bacteria, indicating the regulatory role of PPRs in the stress response via the modulation of RNA editing. The differentially expressed upstream transcription factors of the PPRs were further identified; they may regulate resistance adaption by modulating the expression of the PPRs. Collectively, these results suggest that PPRs play roles in the development and disease resistance of kiwifruit and provide candidate genes for further clarifying the resistance mechanisms in kiwifruits.


Assuntos
Actinidia , Edição de RNA , Edição de RNA/genética , Actinidia/genética , Resistência à Doença/genética , Frutas/genética , Cloroplastos
4.
BMC Plant Biol ; 22(1): 583, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36513981

RESUMO

BACKGROUND: Multiple organellar RNA editing factor (MORF) genes play key roles in chloroplast developmental processes by mediating RNA editing of Cytosine-to-Uracil conversion. However, the function of MORF genes in peach (Prunus persica), a perennial horticultural crop species of Rosaceae, is still not well known, particularly the resistance to biotic and abiotic stresses that threaten peach yield seriously. RESULTS: In this study, to reveal the regulatory roles of RNA editing in plant immunity, we implemented genome-wide analysis of peach MORF (PpMORF) genes in response to biotic and abiotic stresses. The chromosomal and subcellular location analysis showed that the identified seven PpMORF genes distributed on three peach chromosomes were mainly localized in the mitochondria and chloroplast. All the PpMORF genes were classified into six groups and one pair of PpMORF genes was tandemly duplicated. Based on the meta-analysis of two types of public RNA-seq data under different treatments (biotic and abiotic stresses), we observed down-regulated expression of PpMORF genes and reduced chloroplast RNA editing, especially the different response of PpMORF2 and PpMORF9 to pathogens infection between resistant and susceptible peach varieties, indicating the roles of MORF genes in stress response by modulating the RNA editing extent in plant immunity. Three upstream transcription factors (MYB3R-1, ZAT10, HSFB3) were identified under both stresses, they may regulate resistance adaption by modulating the PpMORF gene expression. CONCLUSION: These results provided the foundation for further analyses of the functions of MORF genes, in particular the roles of RNA editing in plant immunity. In addition, our findings will be conducive to clarifying the resistance mechanisms in peaches and open up avenues for breeding new cultivars with high resistance.


Assuntos
Prunus persica , Prunus persica/genética , Prunus persica/metabolismo , Edição de RNA , Melhoramento Vegetal , Organelas/metabolismo , Imunidade Vegetal/genética , Regulação da Expressão Gênica de Plantas
5.
Genes (Basel) ; 13(10)2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36292736

RESUMO

Grapevine (Vitisvinifera L.) fruit ripening is a complex biological process involving a phase transition from immature to mature. Understanding the molecular mechanism of fruit ripening is critical for grapevine fruit storage and quality improvement. However, the regulatory mechanism for the critical phase transition of fruit ripening from immature to mature in grapevine remains poorly understood. In this work, to identify the key molecular events controlling the critical phase transition of grapevine fruit ripening, we performed an integrated dynamic network analysis on time-series transcriptomic data of grapevine berry development and ripening. As a result, we identified the third time point as a critical transition point in grapevine fruit ripening, which is consistent with the onset of veraison reported in previous studies. In addition, we detected 68 genes as being key regulators involved in controlling fruit ripening. The GO (Gene Ontology) analysis showed that some of these genes participate in fruit development and seed development. This study provided dynamic network biomarkers for marking the initial transcriptional events that characterizes the transition process of fruit ripening, as well as new insights into fruit development and ripening.


Assuntos
Frutas , Vitis , Frutas/genética , Vitis/genética , Regulação da Expressão Gênica de Plantas/genética , Transcriptoma/genética , Biomarcadores
6.
Front Immunol ; 13: 906122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35757706

RESUMO

Food allergy is a growing concern due to its increasing world-wide incidence. Strict avoidance of allergens is a passive treatment strategy. Since the mechanisms responsible for the occurrence and development of food allergy have not yet been fully elucidated, effective individualized treatment options are lacking. In this review, we summarize the pathways through which food antigens enter the intestine and review the proposed mechanisms describing how the intestine acquires and tolerates food antigens. When oral tolerance is not established, food allergy occurs. In addition, we also discuss the contribution of commensal bacteria of the gut in shaping tolerance to food antigens in the intestinal tract. Finally, we propose that elucidating the mechanisms of intestinal uptake and tolerance of food antigens will provide additional clues for potential treatment options for food allergy.


Assuntos
Alérgenos , Antígenos/metabolismo , Hipersensibilidade Alimentar , Bactérias , Alimentos , Humanos , Tolerância Imunológica
7.
Plants (Basel) ; 11(6)2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35336617

RESUMO

Terpenes are organic compounds and play important roles in plant development and stress response. Terpene synthases (TPSs) are the key enzymes for the biosynthesis of terpenes. For Rosaceae species, terpene composition represents a critical quality attribute, but limited information is available regarding the evolution and expansion occurring in the terpene synthases gene family. Here, we selected eight Rosaceae species with sequenced and annotated genomes for the identification of TPSs, including three Prunoideae, three Maloideae, and two Rosoideae species. Our data showed that the TPS gene family in the Rosaceae species displayed a diversity of family numbers and functions among different subfamilies. Lineage and species-specific expansion of the TPSs accompanied by frequent domain loss was widely observed within different TPS clades, which might have contributed to speciation or environmental adaptation in Rosaceae. In contrast to Maloideae and Rosoideae species, Prunoideae species owned less TPSs, with the evolution of Prunoideae species, TPSs were expanded in modern peach. Both tandem and segmental duplication significantly contributed to TPSs expansion. Ka/Ks calculations revealed that TPSs genes mainly evolved under purifying selection except for several pairs, where the divergent time indicated TPS-e clade was diverged relatively anciently. Gene function classification of TPSs further demonstrated the function diversity among clades and species. Moreover, based on already published RNA-Seq data from NCBI, the expression of most TPSs in Malus domestica, Prunus persica, and Fragaria vesca displayed tissue specificity and distinct expression patterns either in tissues or expression abundance between species and TPS clades. Certain putative TPS-like proteins lacking both domains were detected to be highly expressed, indicating the underlying functional or regulatory potentials. The result provided insight into the TPS family evolution and genetic information that would help to improve Rosaceae species quality.

8.
Plants (Basel) ; 11(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35050036

RESUMO

Kiwifruit (Actinidia chinensis) is well known for its high vitamin C content and good taste. Various diseases, especially bacterial canker, are a serious threat to the yield of kiwifruit. Multiple organellar RNA editing factor (MORF) genes are pivotal factors in the RNA editosome that mediates Cytosine-to-Uracil RNA editing, and they are also indispensable for the regulation of chloroplast development, plant growth, and response to stresses. Although the kiwifruit genome has been released, little is known about MORF genes in kiwifruit at the genome-wide level, especially those involved in the response to pathogens stress. In this study, we identified ten MORF genes in the kiwifruit genome. The genomic structures and chromosomal locations analysis indicated that all the MORF genes consisted of three conserved motifs, and they were distributed widely across the seven linkage groups and one contig of the kiwifruit genome. Based on the structural features of MORF proteins and the topology of the phylogenetic tree, the kiwifruit MORF gene family members were classified into six groups (Groups A-F). A synteny analysis indicated that two pairs of MORF genes were tandemly duplicated and five pairs of MORF genes were segmentally duplicated. Moreover, based on analysis of RNA-seq data from five tissues of kiwifruit, we found that both expressions of MORF genes and chloroplast RNA editing exhibited tissue-specific patterns. MORF2 and MORF9 were highly expressed in leaf and shoot, and may be responsible for chloroplast RNA editing, especially the ndhB genes. We also observed different MORF expression and chloroplast RNA editing profiles between resistant and susceptible kiwifruits after pathogen infection, indicating the roles of MORF genes in stress response by modulating the editing extend of mRNA. These results provide a solid foundation for further analyses of the functions and molecular evolution of MORF genes, in particular, for clarifying the resistance mechanisms in kiwifruits and breeding new cultivars with high resistance.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(1): 139-42, 2007 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-17390670

RESUMO

The technology of spectral recognition is the foundation of qualitative analysis by spectrum. With the technology of pattern recognition developed, the technology of spectral recognition has been a important tool for quick detection in medicine, environment and petrochemical industry etc. Artificial neural network has many good qualities, such as nonlinear mapping, self-adaptive learning, robustness and fault tolerant ability. It is widely applied in signal procesing, knowledge engineering and pattern recognition etc. The present paper takes spectral signal according with Lambert-Beer' law as object, introduces basic pattern recognition theory of artificial neural network in brief, puts forward spectral recognition method based on multiple features and neural network according to spectral recognition need, makes system design and the basic frame of model, and gives an example for explanation.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(1): 147-50, 2007 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-17390672

RESUMO

The model transfer is a basic method to build up universal and comparable performance of spectrometer data by seeking a mathematical transformation relation among different spectrometers. Because of nonlinear effect and small calibration sample set in fact, it is important to solve the problem of model transfer under the condition of nonlinear effect in evidence and small sample set. This paper summarizes support vector machines theory, puts forward the method of model transfer based on support vector machine and piecewise direct standardization, and makes use of computer simulation method, giving a example to explain the method and compare it with artificial neural network in the end.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(4): 772-4, 2006 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16836159

RESUMO

The fractal theory is a discipline that studies a kind of irregular and chaotic object with similarity of its part and whole. The fractal dimension is a basic index mark of irregularity and self-similarity in the fractal theory. The present paper takes the spectral signal according with Lambert-beer' law as the object, introduces the basic theory of fractal geometry in brief, puts forward the method of fractal dimension as the feature of spectral signal recognition, makes use of reconstructing phase space to gain the fractal dimension of spectral signal, compares different values of the fractal dimension to recognize different spectral signal, and gives an example for explanation.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(8): 1332-5, 2005 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-16329515

RESUMO

Automated recognition of spectral signal is an importance part of spectral analysis, which jnvolves comparing spectral signals under the same conditions and obtaining relation of chemistry constitution according to similarity by pattern recognition method and computer technique, and is useful to determine the nature of spectral signal and validate spectral signal. This paper takes spectral signal according with Lambert-beer' law as object, introduces basic theory and method of recognition of spectral signal in brief, normalizes spectral signal to decrease difficulty, introduces wavelet analysis theory, puts forward the method of wavelet packet analysis to gain features of spectral signal, obtains formula to compute feature vector and error vector by statistics method, then makes use of binary tree' mode distinguishing step by step for quick recognition, and finally gives an example to explain.


Assuntos
Algoritmos , Modelos Estatísticos , Espectrofotometria/métodos , Reconhecimento Automatizado de Padrão , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(3): 346-50, 2005 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-16013303

RESUMO

In a micro spectral analytical system, the non-linearity response of the photoelectronic detecting array pixel will cause the deformation of the spectrum, especially in the measurement of absorption spectrum. In this paper, the factors that cause the deformation were studied and a corresponding solution was proposed to reduce such deformation. By using curve fitting, the non-linearity of the pixel can be corrected. This method was adopted to correct the absorption spectrum obtained by a micro spectral analytical system and the result showed that it is a efficient way to correct the non-linearity in the pixel of photoelectronic detecting array.


Assuntos
Algoritmos , Análise Espectral/métodos , Luz , Dinâmica não Linear , Espalhamento de Radiação
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