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1.
Appl Opt ; 62(26): 6939-6951, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37707033

RESUMO

For the Palmer mechanical scanning pattern of an airborne laser bathymetry system, the potential errors of the scanning system are analyzed, and the associated error model is derived. The model composes the description of laser rays, water surface fluctuations, and refraction, and introduces certain simplifications concerning the water surface and column. Based on the scanning error model, the impact of each error source on the vertical and horizontal positioning accuracy is investigated and established through a numerical simulation. The quantitative impacts of each inaccuracy on the coordinates of the laser footprints on the sea surface and bottom were calculated, with a height of 100 m for the airborne platform and a water depth of 10 m. To verify the correctness of the simulation results and the error model based on a theoretical analysis, experiments are utilized with the system that we developed. Both the simulation analysis and experimental results show that this method can effectively obtain the systematic errors. The outcomes of the error model and analysis will give the theoretical foundations for lowering the effect brought on by each error source in the compensation scanning system and improving the point cloud accuracy in the ensuing data processing.

2.
Zhongguo Zhong Yao Za Zhi ; 43(20): 4033-4043, 2018 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-30486527

RESUMO

The research is aimed to study of the influence of environmental factors on the yield and quality traits, and find out the regularity of the growth and development of perilla. The main environmental factor data in six ecological area in Guizhou province were collected, and the correlation analysis with yield and quality traits of 15 perilla strains was conducted. The results showed that the cultivation environment has significant effects on the yield and quality traits of perilla. The effect of environment on main yield composed traits, contained grain number in top spike, effective panicle number per plant, plant height, top spike length, growth period, and thousand seed weight was degressive. In the different environmental factors, the latitude showed positive correlation with yield, growth period and effective panicle number per plant, and negative correlation with top spike length and grain number in top spike. Elevation showed negative correlation with the growth period of perilla. The perilla yield increased at first and then decreased with altitude rising, with the maximum in the 800 m altitude. The 600-900 m altitude is suitable area for perilla. Except for positive correlation with the plant height, and negative correlation with top spike length, the longitude showed in apparent impact on other traits. Sunshine duration, temperature and rainfall accumulation showed different effect on the different perilla strains. For yield composed traits, the sunshine duration was negatively correlation with the plant length. The accumulated temperature and mean temperature showed negative correlation with the main spike length, the rainfall showed negative correlation with the precipitation and growth period, plant height, ear number. The environmental impact on the oil compounds decreased with oleic acid, stearic acid, linoleic acid, α-linolenic acid, palmitic acid and oil content. Correlation analysis showed that the significantly negative correlation between the oil content and palmitic acid and linoleic acid content, and the positive correlation between linolenic acid content, α-linolenic acid content showed significant negative correlation with other fatty acids composition, and palmitic acid, stearic acid, oleic acid, linoleic acid showed significant positive correlation with each other. The influence of different environmental factors on the quality of perilla were as follows: the oil content was positively associated with elevation and sunshine duration. α-Linolenic acid content showed negative correlation with longitude, latitude, accumulated temperature and mean temperature, but positive correlation with altitude, sunlight and rainfall capacity. The correlation between palmitic acid, stearic acid, oleic acid, linoleic acid and environmental factors showed contrast character of α-linolenic acid. This study detailed discussed the influence of environmental factors on the quality of perilla, which provided the foundation of ecological planting technology and geoherbalism research of perilla.


Assuntos
Meio Ambiente , Perilla frutescens/química , Perilla frutescens/crescimento & desenvolvimento , Compostos Fitoquímicos/análise , Ácidos Graxos/análise , Óleos de Plantas/análise
3.
Int J Mol Sci ; 18(11)2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-29144390

RESUMO

Perillafrutescen is used as traditional food and medicine in East Asia. Its seeds contain high levels of α-linolenic acid (ALA), which is important for health, but is scarce in our daily meals. Previous reports on RNA-seq of perilla seed had identified fatty acid (FA) and triacylglycerol (TAG) synthesis genes, but the underlying mechanism of ALA biosynthesis and its regulation still need to be further explored. So we conducted Illumina RNA-sequencing in seven temporal developmental stages of perilla seeds. Sequencing generated a total of 127 million clean reads, containing 15.88 Gb of valid data. The de novo assembly of sequence reads yielded 64,156 unigenes with an average length of 777 bp. A total of 39,760 unigenes were annotated and 11,693 unigenes were found to be differentially expressed in all samples. According to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, 486 unigenes were annotated in the "lipid metabolism" pathway. Of these, 150 unigenes were found to be involved in fatty acid (FA) biosynthesis and triacylglycerol (TAG) assembly in perilla seeds. A coexpression analysis showed that a total of 104 genes were highly coexpressed (r > 0.95). The coexpression network could be divided into two main subnetworks showing over expression in the medium or earlier and late phases, respectively. In order to identify the putative regulatory genes, a transcription factor (TF) analysis was performed. This led to the identification of 45 gene families, mainly including the AP2-EREBP, bHLH, MYB, and NAC families, etc. After coexpression analysis of TFs with highly expression of FAD2 and FAD3 genes, 162 TFs were found to be significantly associated with two FAD genes (r > 0.95). Those TFs were predicted to be the key regulatory factors in ALA biosynthesis in perilla seed. The qRT-PCR analysis also verified the relevance of expression pattern between two FAD genes and partial candidate TFs. Although it has been reported that some TFs are involved in seed development, more direct evidence is still needed to verify their function. However, these findings can provide clues to reveal the possible molecular mechanisms of ALA biosynthesis and its regulation in perilla seed.


Assuntos
Genes de Plantas , Perilla/genética , Ácido alfa-Linolênico/biossíntese , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Perilla/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sementes/genética , Sementes/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ácido alfa-Linolênico/genética
4.
Zhongguo Zhong Yao Za Zhi ; 42(9): 1668-1672, 2017 May.
Artigo em Chinês | MEDLINE | ID: mdl-29082687

RESUMO

Perilla frutescens is one of 60 kinds of food and medicine plants in the initial directory announced by health ministry of China. With the development of Perilla domain in recent , the breeding and application of good varieties has become the main bottleneck of its development. This study reported that applied to the system selection, add to marker-assisted method to breed perilla varieties. Through the whole genome sequencing and consistency matching, annotated the mutation locus according to genome data, and comparison analysis with Perilla common variants database, finally selected 30 non-synonymous mutation SNPs used as characteristic markers of Zhongyan Feishu No.1. those SNP marker were used as chosen standard of Perilla varieties. Finally breeding new perilla variety Zhongyan Feishu No.1, which possess to characters of the leaf and seed dual-used, high yield, high resistance, and could used to green fertilizer. The Zhongyan Feishu No.1 acquired the plant new varieties identification of Beijing city , the identification numbers is 2016054. Marker assisted identification guide new varieties breeding in plants, which can provide a new reference for breeding of medicinal plants.


Assuntos
Marcadores Genéticos , Perilla frutescens/genética , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único , China , Plantas Medicinais/genética
5.
Org Lett ; 26(20): 4297-4301, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38739778

RESUMO

A three-component reaction for the synthesis of dihydropyrrolo[3,4-e][1,3]thiazines has been developed. Elemental sulfur, maleimides, and 1,3,5-triazinanes are assembled together through sulfuration/nucleophilic attack in N-methylpyrrolidin-2-one (NMP) under mild conditions. A small amount of NaHCO3 is important for the activation of the reaction. In this method, sulfur plays a dual role in thiazine ring formation, while triazinanes are utilized as three-atom synthons in the annulation reaction.

6.
Front Microbiol ; 15: 1349305, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887707

RESUMO

Intercropping systems can improve soil fertility and health, however, soil microbial communities and functional genes related to carbon, nitrogen and phosphorus cycling under the intercropping system of mesquite and perilla have not been studied. Therefore, in the present study, different planting densities and varieties of Perilla frutescens (L.) Britt and kiwifruit were used for intercropping, and changes in soil microbial communities and carbon, nitrogen, and phosphorus cycling genes in kiwifruit inter-roots under inter-cropping conditions were investigated by macro-genome sequencing technology. The results showed that intercropping with Perill caused a decrease in most soil nutrients, soil enzyme activities, and had a significant impact on the microbial (bacteria and fungi) diversity. Inter-cropping increased the relative abundance of the dominant bacterial phylum "Proteobacteria" and "Actinobacteria" by 47 and 57%, respectively, but decreased the relative abundance of the dominant fungal phylum "Chordata" and "Streptophyta" by 11 and 20%, respectively, in the inter-root soil of kiwifruit, and had a significant impact on the microbial (bacteria and fungi) diversity. In addition, inter-cropping could greatly increase the inter-root soil carbon sequestration (PccA, korA/B/C/D, fhs, and rbcl/s), carbon degradation (abfD), organic nitrogen mineralization (GDH2), denitrification (napA/B, nirB, norB), organic phosphorus mineralization (phop, phn), and inorganic phosphorus solubilization (gcd, ppk) gene abundance. The gene co-occurrence network indicated that soil korB, nirB, and gnd key functional genes for carbon, nitrogen, and phosphorus cycling in kiwifruit inter-root soils and their expression was up-regulated in the inter-cropping group. Structural equation (SEM) further showed that soil total nitrogen, organic matter, total carbon and acid phosphatase had significant effects on microbial diversity (p < 0.05) and soil carbon cycling gene korB and phosphorus cycling gene purH (p < 0.001), while korB and purH had positive effects on kiwifruit quality. In conclusion, intercropping perilla in kiwifruit orchards changed the structure of bacterial and fungal communities in the inter-root soil of kiwifruit, but I believe that intercropping perilla stimulates carbon degradation, leading to carbon emission and serious loss of soil nutrients, and that prolonged intercropping may adversely affect the quality of kiwifruit, and thus its limitations should be noted in future studies.

7.
Int J Stem Cells ; 16(2): 135-144, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-36823977

RESUMO

Background and Objectives: Melanocyte (MC), derived from neural crest stem cell (NCSC), are involved in the production of melanin. The mechanism by which NCSC differentiates to MC remains unclear. N6-methyladenosine (m6A) modification was applied to discuss the potential mechanism. Methods and Results: NCSCs were isolated from hair follicles of rats, and were obtained for differentiation. Cell viability, tyrosinase secretion and activity, and transcription factors were combined to evaluated the MC differentiation. RT-qPCR was applied to determine mRNA levels, and western blot were used for protein expression detection. Total m6A level was measured using methylated RNA immunoprecipitation (MeRIP) assay, and RNA immunoprecipitation was used to access the protein binding relationship. In current work, NCSCs were successfully differentiated into MCs. Fat mass and obesity associated gene (FTO) was aberrant downregulated in MCs, and elevated FTO suppressed the differentiation progress of NCSCs into MCs. Furthermore, microphthalmia-associated transcription factor (Mitf), a key gene involved in MC synthesis, was enriched by FTO in a m6A modification manner and degraded by FTO. Meanwhile, the suppression functions of FTO in the differentiation of NCSCs into MCs were reversed by elevated Mitf. Conclusions: In short, FTO suppressed the differentiating ability of hair follicle-derived NCSCs into MCs by m6A modifying Mitf.

8.
Artigo em Inglês | MEDLINE | ID: mdl-37943648

RESUMO

In this article, a novel reinforcement learning (RL) approach, continuous dynamic policy programming (CDPP), is proposed to tackle the issues of both learning stability and sample efficiency in the current RL methods with continuous actions. The proposed method naturally extends the relative entropy regularization from the value function-based framework to the actor-critic (AC) framework of deep deterministic policy gradient (DDPG) to stabilize the learning process in continuous action space. It tackles the intractable softmax operation over continuous actions in the critic by Monte Carlo estimation and explores the practical advantages of the Mellowmax operator. A Boltzmann sampling policy is proposed to guide the exploration of actor following the relative entropy regularized critic for superior learning capability, exploration efficiency, and robustness. Evaluated by several benchmark and real-robot-based simulation tasks, the proposed method illustrates the positive impact of the relative entropy regularization including efficient exploration behavior and stable policy update in RL with continuous action space and successfully outperforms the related baseline approaches in both sample efficiency and learning stability.

9.
J Mater Chem B ; 11(46): 11052-11063, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-37946538

RESUMO

MicroRNAs (miRNAs) have been identified as promising disease diagnostic biomarkers. However, it is challenging to sensitively detect miRNAs, especially in complex biological environments, due to their low abundance and small size. Herein, we have developed a DNA-fueled molecular machine for sensitive detection of miRNA-22 (miR-22) in undiluted serum by combining poly-adenine-mediated spherical nucleic acids (polyA-SNAs) with a toehold mediated strand displacement reaction (TMSDR). The polyA-SNAs are constructed by the assembly of diblock DNA probes on a AuNP surface through the high binding affinity of polyA to AuNPs. The surface density of the diblock DNA probe can be controlled by tuning the length of the polyA block, and the orientation of the diblock DNA probe can adopt an upright conformation, which is beneficial to target hybridization and TMSDRs. TMSDR is an enzyme-free target recycling amplification approach. Taking advantage of polyA-mediated SNAs and TMSDR, the operation of the molecular machine based on two successive TMSDRs on polyA20-SNAs is rapid and efficient, which can significantly amplify the fluorescence response for detection of miR-22 in an undiluted complex matrix. The developed sensor can detect as low as 10 pM of target miRNA/DNA in undiluted fetal bovine serum within 30 min. The synergetic effect of polyA-mediated SNAs and TMSDR presents a potential alternative tool for the detection of biomarkers in real biological samples.


Assuntos
Nanopartículas Metálicas , MicroRNAs , Ácidos Nucleicos , MicroRNAs/metabolismo , Ouro/química , Nanopartículas Metálicas/química , DNA/química , Sondas de DNA/química , Biomarcadores
10.
Anal Methods ; 15(42): 5564-5576, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37861233

RESUMO

Owing to the versatile photophysical and chemical properties, spherical nucleic acids (SNAs) have been widely used in biosensing. However, traditional SNAs are formed by self-assembly of thiolated DNA on the surface of a gold nanoparticle (AuNP), where it is challenging to precisely control the orientation and surface density of DNA. As a new SNA, a polyadenine (polyA)-mediated SNA using the high binding affinity of consecutive adenines to AuNPs shows controllable surface density and configuration of DNA, which can be used to improve the performance of a biosensor. Herein, we first introduce the properties of polyA-mediated SNAs and fundamental principles regarding the polyA-AuNP interaction. Then, we provide an overview of current representative synthesis methods of polyA-mediated SNAs and their advantages and disadvantages. After that, we summarize the application of polyA-mediated SNAs in biosensing based on fluorescence and colorimetric methods, followed by discussion and an outlook of future challenges in this field.


Assuntos
Nanopartículas Metálicas , Ácidos Nucleicos , Ouro/química , Hibridização de Ácido Nucleico/métodos , Nanopartículas Metálicas/química , DNA/química
11.
Oncol Lett ; 15(1): 630-634, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29375720

RESUMO

Propofol is an intravenous anesthetic, which is widely used in clinical anesthesia induction and maintenance and is critical in the sedation of patients. However, the functions and mechanisms of propofol on apoptosis of melanoma cells remain unclear. The present study investigated whether propofol promotes cell apoptosis and suppresses the HOX transcript antisense RNA (HOTAIR)-mediated mechanistic target of rapamycin (mTOR) pathway in melanoma cells. B16F10 cells were cultured with different concentrations (0-10 µM) of propofol for 24 or 48 h. Proliferation and apoptosis of B16F10 cells were detected using MTT assay and flow cytometry. The pcDNA 3.1(-)-HOTAIR and pcDNA 3.1(-)-control plasmids were transfected into B16F10 cells using Lipofectamine 2000. In the present study, treatment with propofol significantly reduced viability, and induced apoptosis and caspase-3 activity in melanoma cells. Propofol treatment significantly inhibited HOTAIR expression and the expression of phosphorylated (p)-mTOR and p- p70S6K protein in melanoma cells. Overexpression of HOTAIR significantly increased viability of melanoma cells, and increased HOTAIR, p-mTOR and p-p70S6K protein expression in melanoma cells. These results indicated that propofol promotes apoptosis and suppresses the HOTAIR-mediated mTOR signaling pathway in melanoma cells.

12.
J Dermatol ; 44(10): 1138-1144, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28500632

RESUMO

Vitiligo is an acquired skin disease with pigmentary disorder. Autoimmune destruction of melanocytes is thought to be major factor in the etiology of vitiligo. miRNA-based regulators of gene expression have been reported to play crucial roles in autoimmune disease. Therefore, we attempt to profile the miRNA expressions and predict their potential targets, assessing the biological functions of differentially expressed miRNA. Total RNA was extracted from peripheral blood of vitiligo (experimental group, n = 5) and non-vitiligo (control group, n = 5) age-matched patients. Samples were hybridized to a miRNA array. Box, scatter and principal component analysis plots were performed, followed by unsupervised hierarchical clustering analysis to classify the samples. Quantitative reverse transcription polymerase chain reaction (RT-PCR) was conducted for validation of microarray data. Three different databases, TargetScan, PITA and microRNA.org, were used to predict the potential target genes. Gene ontology (GO) annotation and pathway analysis were performed to assess the potential functions of predicted genes of identified miRNA. A total of 100 (29 upregulated and 71 downregulated) miRNA were filtered by volcano plot analysis. Four miRNA were validated by quantitative RT-PCR as significantly downregulated in the vitiligo group. The functions of predicted target genes associated with differentially expressed miRNA were assessed by GO analysis, showing that the GO term with most significantly enriched target genes was axon guidance, and that the axon guidance pathway was most significantly correlated with these miRNA. In conclusion, we identified four downregulated miRNA in vitiligo and assessed the potential functions of target genes related to these differentially expressed miRNA.


Assuntos
Perfilação da Expressão Gênica , MicroRNAs/metabolismo , Pele/patologia , Vitiligo/genética , Adulto , Biologia Computacional , Regulação para Baixo , Feminino , Ontologia Genética , Humanos , Masculino , MicroRNAs/isolamento & purificação , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Regulação para Cima , Vitiligo/sangue , Vitiligo/patologia , Adulto Jovem
13.
Int J Clin Exp Med ; 8(7): 11048-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26379904

RESUMO

Giant congenital melanocytic nevi (GCMN) are rare conditions that defined as melanocytic lesion recognized at birth, which will reach a diameter larger than 20 cm, and they occur in about 1 per 500,000 newborns. Despite its rarity, they may associate with severe abnormalities like spina bifida occulta, meningocele, club foot and hypertrophy or atrophy of deeper structures of a limb, Carney complex, premature aging syndromes, neurofibroma, vitiligo, lipoma and dysplasia of bilateral hip impact on the patient. In this case, we report a 3-years-old male child presenting a GCMN with large, blackish, and thick nevus covering over the entire neck, back, and lower to the waist level. We highlight the importance of proper histopathological examination of the biopsy taken from the single huge nodule which revealed features of both neurofibroma and lipoma coexisting. The objective of this paper is to report a rare case with the clinical and pathologic findings.

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