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1.
Mar Drugs ; 21(7)2023 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-37504949

RESUMO

Lutein is a high-value carotenoid with many human health benefits. Lycopene ß- and ε-cyclases (LCYB and LCYE, respectively) catalyze the cyclization of lycopene into distinct downstream branches, one of which is the lutein biosynthesis pathway, via α-carotene. Hence, LCYB and LCYE are key enzymes in lutein biosynthesis. In this study, the coding genes of two lycopene cyclases (CsLCYB and CsLCYE) of a lutein-enriched marine green microalga, Chlorella sorokiniana FZU60, were isolated and identified. A sequence analysis and computational modeling of CsLCYB and CsLCYE were performed using bioinformatics to identify the key structural domains. Further, a phylogenetic analysis revealed that CsLCYB and CsLCYE were homogeneous to the proteins of other green microalgae. Subcellular localization tests in Nicotiana benthamiana showed that CsLCYB and CsLCYE localized in chloroplasts. A pigment complementation assay in Escherichia coli revealed that CsLCYB could efficiently ß-cyclize both ends of lycopene to produce ß-carotene. On the other hand, CsLCYE possessed a strong ε-monocyclase activity for the production of δ-carotene and a weak ε-bicyclic activity for the production of ε-carotene. In addition, CsLCYE was able to catalyze lycopene into ß-monocyclic γ-carotene and ultimately produced α-carotene with a ß-ring and an ε-ring via γ-carotene or δ-carotene. Moreover, the co-expression of CsLCYB and CsLCYE in E. coli revealed that α-carotene was a major product, which might lead to the production of a high level of lutein in C. sorokiniana FZU60. The findings provide a theoretical foundation for performing metabolic engineering to improve lutein biosynthesis and accumulation in C. sorokiniana FZU60.


Assuntos
Chlorella , Liases Intramoleculares , Microalgas , Humanos , Licopeno/metabolismo , Luteína/metabolismo , Chlorella/genética , Chlorella/metabolismo , Microalgas/genética , Microalgas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Filogenia , Carotenoides/metabolismo , beta Caroteno/metabolismo , Liases Intramoleculares/genética , Liases Intramoleculares/metabolismo
2.
Plant Biotechnol J ; 19(1): 192-205, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32722872

RESUMO

Flat peaches have become popular worldwide due to their novelty and convenience. The peach flat fruit trait is genetically controlled by a single gene at the S locus, but its genetic basis remains unclear. Here, we report a 1.7-Mb chromosomal inversion downstream of a candidate gene encoding OVATE Family Protein, designated PpOFP1, as the causal mutation for the peach flat fruit trait. Genotyping of 727 peach cultivars revealed an occurrence of this large inversion in flat peaches, but absent in round peaches. Ectopic overexpression of PpOFP1 resulted in oval-shaped leaves and shortened siliques in Arabidopsis, suggesting its role in repressing cell elongation. Transcriptional activation of PpOFP1 by the chromosomal inversion may repress vertical elongation in flat-shaped fruits at early stages of development, resulting in the flat fruit shape. Moreover, PpOFP1 can interact with fruit elongation activator PpTRM17, suggesting a regulatory network controlling fruit shape in peach. Additionally, screening of peach wild relatives revealed an exclusive presence of the chromosomal inversion in P. ferganensis, supporting that this species is the ancestor of the domesticated peach. This study provides new insights into mechanisms underlying fruit shape evolution and molecular tools for genetic improvement of fruit shape trait in peach breeding programmes.


Assuntos
Prunus persica , Inversão Cromossômica/genética , Frutas/genética , Genes de Plantas , Melhoramento Vegetal , Prunus persica/genética
3.
Plant Physiol ; 182(4): 2065-2080, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32001520

RESUMO

Aroma contributes to the unique flavors of fruits and is important for fruit quality evaluation. Among the many volatiles in peach (Prunus persica) fruits, γ-decalactone has the greatest contribution to the characteristic peach aroma. Some peach cultivars have γ-decalactone contents that are too low to detect. Comparison of the transcriptomes and metabolomes of a high-aroma cultivar, Fenghuayulu, and a low-aroma cultivar, Achutao, suggested that amino acid substitutions in ALCOHOL ACYLTRANSFERASE (PpAAT1) are responsible for the undetectable levels of γ-decalactone in cv Achutao fruit. Modeling and molecular docking analysis of PpAAT1 indicated that the substituted residues might determine substrate recognition or act as control channels to the active site. In vitro enzyme assays on PpAAT1 heterologously expressed and purified from Escherichia coli and in vivo assays using transient PpAAT1 expression in Nicotiana benthamiana or the oleaginous yeast Yarrowia lipolytica indicated that PpAAT1 from high-aroma cultivars was more efficient than PpAAT1 from low-aroma cultivars in catalyzing the conversion of 4-hydroxydecanoyl-coenzyme A into γ-decalactone. Examination of loss-of-function mutations of PpAAT1 generated by CRISPR/Cas9 in cv Fenghuayulu showed that fruits with PpAAT1 mutations had significantly lower γ-decalactone contents. Expression of the version of PpAAT1 from cv Fenghuayulu in cv Achutao restored γ-decalactone levels to those measured in 'Fenghuayulu', confirming the specific contribution of PpAAT1 to the formation of this key aroma compound. These results show how the biosynthesis of the peach aroma compound γ-decalactone is compromised in some low-aroma cultivars and illustrate the physiological role of PpAAT1 in plant lactone biosynthesis.


Assuntos
Lactonas/metabolismo , Nicotiana/metabolismo , Prunus persica/metabolismo , Mutação , Odorantes , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Prunus persica/genética , Nicotiana/genética
4.
Mar Drugs ; 18(9)2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32948074

RESUMO

Marine microalgae are regarded as potential feedstock because of their multiple valuable compounds, including lipids, pigments, carbohydrates, and proteins. Some of these compounds exhibit attractive bioactivities, such as carotenoids, ω-3 polyunsaturated fatty acids, polysaccharides, and peptides. However, the production cost of bioactive compounds is quite high, due to the low contents in marine microalgae. Comprehensive utilization of marine microalgae for multiple compounds production instead of the sole product can be an efficient way to increase the economic feasibility of bioactive compounds production and improve the production efficiency. This paper discusses the metabolic network of marine microalgal compounds, and indicates their interaction in biosynthesis pathways. Furthermore, potential applications of co-production of multiple compounds under various cultivation conditions by shifting metabolic flux are discussed, and cultivation strategies based on environmental and/or nutrient conditions are proposed to improve the co-production. Moreover, biorefinery techniques for the integral use of microalgal biomass are summarized. These techniques include the co-extraction of multiple bioactive compounds from marine microalgae by conventional methods, super/subcritical fluids, and ionic liquids, as well as direct utilization and biochemical or thermochemical conversion of microalgal residues. Overall, this review sheds light on the potential of the comprehensive utilization of marine microalgae for improving bioeconomy in practical industrial application.


Assuntos
Produtos Biológicos/metabolismo , Biotecnologia , Microalgas/metabolismo , Produtos Biológicos/economia , Produtos Biológicos/farmacologia , Biomassa , Biotecnologia/economia , Análise Custo-Benefício , Metabolismo Energético
5.
Mar Drugs ; 17(8)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374944

RESUMO

Microalgae are considered as excellent candidates for bioactive compounds, yet microalgal residues remaining after the extraction of one or two compounds are usually discarded, which is not economical. This study demonstrates the alkaline extraction of proteins from Chlorella pyrenoidosa residue after lipid and pigment extractions, and their functional properties. Single-factor experiments and response surface methodology were used to obtain the optimal conditions for protein extraction. Based on our results, a maximum protein yield of 722.70 mg/g, was obtained under the following extraction conditions: sodium hydroxide concentration 7.90%, extraction temperature 70.00 °C, extraction time 34.80 min, and microalgal residue concentration 8.20 mg/mL. The molecular weight of microalgal residue protein isolate (MRPI) was mainly distributed at the regions of 0.18-0.50 kDa, 0.50-1.50 kDa, and 1.50-5.00 kDa. The essential amino acid content was greater than the values recommended by FAO/WHO standards; a high essential amino acid index value (1.49) was another good indication that MRPI is suitable for human consumption. Moreover, MRPI exhibited excellent emulsifying properties and antioxidant activity, which suggests it may be useful as an emulsifying agent and antioxidant. These findings could improve the extraction methods of functional protein from microalgal residue and add value to microalgae-based bioactive compound production processes.


Assuntos
Chlorella/química , Microalgas/química , Extratos Vegetais/farmacologia , Proteínas de Plantas/farmacologia , Sequência de Aminoácidos , Aminoácidos Essenciais/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Emulsificantes/química , Emulsificantes/isolamento & purificação , Emulsificantes/farmacologia , Alimento Funcional , Lipídeos/isolamento & purificação , Peso Molecular , Estresse Oxidativo/efeitos dos fármacos , Pigmentos Biológicos/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Hidróxido de Sódio/química , Temperatura
6.
Bioprocess Biosyst Eng ; 42(3): 435-443, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30467772

RESUMO

The marine microalga Chlamydomonas sp. JSC4 was examined for its potential as a lutein producer. Environmental conditions, including light quality, temperature and light wavelength mixing ratio, were individually altered to enhance the cell growth rate and lutein production in strain JSC4. Results showed that optimal cell growth was obtained under white light and a temperature of 35 °C, while the optimal lutein content was obtained under blue light and a lower temperature of 20-25 °C. The best lutein production occurred when using a mixing ratio of 3:1 (white light: blue light). Strategies related to light quality and temperature (namely, temperature-gradient and two-stage strategies) were then used to further improve lutein production. Among them, the two-stage strategy proved to be effective markedly improving lutein content from 2.52 to 4.24 mg/g and resulting in the highest lutein productivity of 3.25 mg/L/day.


Assuntos
Chlamydomonas/crescimento & desenvolvimento , Luz , Luteína/biossíntese , Microalgas/crescimento & desenvolvimento
7.
BMC Genomics ; 19(1): 612, 2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-30107781

RESUMO

BACKGROUND: Peach (Prunus persica) is an important fruit crop that generally softens rapidly after harvest resulting in a short shelf-life. By contrast, stony hard (SH) peach fruit does not soften and hardly produces ethylene. To explore the candidate genes responsible for the SH phenotype, a high-density genetic map was constructed by restriction-site associated DNA sequencing technology. RESULTS: In the present study, the linkage map consisted of 1310 single nucleotide polymorphism markers, spanning 454.2 cM, with an average marker distance of 0.347 cM. The single nucleotide polymorphisms were able to anchor eight linkage groups to their corresponding chromosomes. Based on this high-density integrated peach linkage map and two years of fruit phenotyping, two potential quantitative trait loci for the SH trait were identified and positioned on the genetic map. Additionally, Prupe.6G150900.1, a key gene in abscisic acid (ABA) biosynthesis, displayed a differential expression profile identical to the ABA accumulation pattern: mRNA transcripts were maintained at a high level during storage of SH peaches but occurred at low levels in melting fruit. CONCLUSION: Thus Prupe.6G150900.1 might play a crucial role in the SH phenotype of peach in which ABA negatively regulates ethylene production. Also, this high-density linkage map of peach will contribute to the mapping of important fruit traits and quantitative trait loci identification.


Assuntos
Estudos de Associação Genética/métodos , Polimorfismo de Nucleotídeo Único , Prunus persica/genética , Locos de Características Quantitativas , Perfilação da Expressão Gênica , Mapeamento por Restrição , Análise de Sequência de DNA
8.
Mar Drugs ; 15(10)2017 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-29019908

RESUMO

The PII signaling protein is a key protein for controlling nitrogen assimilatory reactions in most organisms, but little information is reported on PII proteins of green microalga Haematococcus pluvialis. Since H. pluvialis cells can produce a large amount of astaxanthin upon nitrogen starvation, its PII protein may represent an important factor on elevated production of Haematococcus astaxanthin. This study identified and isolated the coding gene (HpGLB1) from this microalga. The full-length of HpGLB1 was 1222 bp, including 621 bp coding sequence (CDS), 103 bp 5' untranslated region (5' UTR), and 498 bp 3' untranslated region (3' UTR). The CDS could encode a protein with 206 amino acids (HpPII). Its calculated molecular weight (Mw) was 22.4 kDa and the theoretical isoelectric point was 9.53. When H. pluvialis cells were exposed to nitrogen starvation, the HpGLB1 expression was increased 2.46 times in 48 h, concomitant with the raise of astaxanthin content. This study also used phylogenetic analysis to prove that HpPII was homogeneous to the PII proteins of other green microalgae. The results formed a fundamental basis for the future study on HpPII, for its potential physiological function in Haematococcus astaxanthin biosysthesis.


Assuntos
Clorófitas/metabolismo , Microalgas/metabolismo , Proteínas PII Reguladoras de Nitrogênio/genética , Sequência de Aminoácidos , Clorófitas/genética , Ponto Isoelétrico , Microalgas/genética , Peso Molecular , Nitrogênio/metabolismo , Proteínas PII Reguladoras de Nitrogênio/química , Filogenia , Transdução de Sinais , Fatores de Tempo , Xantofilas/biossíntese
10.
J Clin Lab Anal ; 29(2): 85-93, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24687454

RESUMO

BACKGROUND: Glypican-3 (GPC3) is an oncofetal antigen that shows great promise as a biomarker for diagnosis of hepatocellular carcinoma (HCC), but there is no reliable kit that can be used to detect it in clinics. The aim of this study is to develop a stable performance kit for GPC3 detection in clinics. DESIGN AND METHODS: The paired antibodies were identified through cycle-screening methods based on our previous research. Then, a double antibodies sandwich chemiluminescent immunoassay for detecting serum GPC3 was developed. The performance of the developed GPC3 diagnostic kit was evaluated by detecting the concentration of serum GPC3 and assessing its single or combined use with alpha fetoprotein (AFP) and cytokeratin 19 fragment (CK19) for HCC diagnosis. RESULTS: The assay demonstrated a linear range of 10-800 ng/ml, the cross-reactivity rate at 0.018% (AFP), 0.020% (carcino-embryonic antigen), and 0.021% (CK19), respectively. The minimum detectable concentration was 0.05 ng/ml; the intraassay coefficient of variation (CV) and interassay CV were both less than 10%, with good stability and reproducibility. GPC3 has a high sensitivity (54.2%) and specificity (99.4%) in diagnosing HCC. The level of GPC3 in HCC was robust higher than that in healthy or other liver diseases' sera (108.67 ± 230.04 ng/ml vs. 3.99 ± 7.68 ng/ml). The diagnostic sensitivity of GPC3 single or combined with CK19 and AFP for HCC was evaluated, and the rates were 54.2 and 90.6%, respectively. CONCLUSIONS: An applicable chemiluminescent immunoassay with stable performance against GPC3 in diagnosing HCC has been established and the combination of GPC3 with CK19 and AFP could improve the diagnostic sensitivity for HCC.


Assuntos
Carcinoma Hepatocelular/sangue , Glipicanas/sangue , Queratina-19/sangue , Neoplasias Hepáticas/sangue , Medições Luminescentes/métodos , alfa-Fetoproteínas/análise , Biomarcadores Tumorais/sangue , Humanos , Imunoensaio/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
BMC Genet ; 14: 84, 2013 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-24041442

RESUMO

BACKGROUND: Peach (Prunus persica (L.) Batsch) is one of the most important model fruits in the Rosaceae family. Native to the west of China, where peach has been domesticated for more than 4,000 years, its cultivation spread from China to Persia, Mediterranean countries and to America. Chinese peach has had a major impact on international peach breeding programs due to its high genetic diversity. In this research, we used 48 highly polymorphic SSRs, distributed over the peach genome, to investigate the difference in genetic diversity, and linkage disequilibrium (LD) among Chinese cultivars, and North American and European cultivars, and the evolution of current peach cultivars. RESULTS: In total, 588 alleles were obtained with 48 SSRs on 653 peach accessions, giving an average of 12.25 alleles per locus. In general, the average value of observed heterozygosity (0.47) was lower than the expected heterozygosity (0.60). The separate analysis of groups of accessions according to their origin or reproductive strategies showed greater variability in Oriental cultivars, mainly due to the high level of heterozygosity in Chinese landraces. Genetic distance analysis clustered the cultivars into two main groups: one included four wild related Prunus, and the other included most of the Oriental and Occidental landraces and breeding cultivars. STRUCTURE analysis assigned 469 accessions to three subpopulations: Oriental (234), Occidental (174), and Landraces (61). Nested STRUCTURE analysis divided the Oriental subpopulation into two different subpopulations: 'Yu Lu' and 'Hakuho'. The Occidental breeding subpopulation was also subdivided into nectarine and peach subpopulations. Linkage disequilibrium (LD) analysis in each of these subpopulations showed that the percentage of linked (r2 > 0.1) intra-chromosome comparisons ranged between 14% and 47%. LD decayed faster in Oriental (1,196 Kbp) than in Occidental (2,687 Kbp) samples. In the 'Yu Lu' subpopulation there was considerable LD extension while no variation of LD with physical distance was observed in the landraces. From the first STRUCTURE result, LG1 had the greatest proportion of alleles in LD within all three subpopulations. CONCLUSIONS: Our study demonstrates a high level of genetic diversity and relatively fast decay of LD in the Oriental peach breeding program. Inclusion of Chinese landraces will have a greater effect on increasing genetic diversity in Occidental breeding programs. Fingerprinting with genotype data for all 658 cultivars will be used for accession management in different germplasms. A higher density of markers are needed for association mapping in Oriental germplasm due to the low extension of LD. Population structure and evaluation of LD provides valuable information for GWAS experiment design in peach.


Assuntos
Variação Genética , Genoma de Planta , Desequilíbrio de Ligação , Prunus/genética , Alelos , Teorema de Bayes , Cruzamento , Mapeamento Cromossômico , Análise por Conglomerados , Genética Populacional , Genótipo , Heterozigoto , Repetições de Microssatélites , Filogenia , Análise de Componente Principal , Prunus/classificação
12.
Foods ; 12(8)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37107443

RESUMO

Peach (Prunus persica (L.) Batsch) is a highly desirable fruit that is consumed around the world. However, the peach fruit is highly perishable after harvest, a characteristic that limits the distribution and supply to the market and causes heavy economic losses. Thus, peach fruit softening and senescence after harvest urgently need to be addressed. In the current study, transcriptomic analysis was performed to identify candidate genes associated with peach fruit softening and senescence, comparing peach fruit from cultivars with different flesh textures, namely melting and stony hard (SH) flesh textures during storage at room temperature. The mitogen-activated protein kinase signaling pathway-plant and plant hormone signal transduction pathways were associated with peach fruit softening and senescence according to the Venn diagram analysis and weighted gene co-expression network analysis. The expression levels of seven genes, including Prupe.1G034300, Prupe.2G176900, Prupe.3G024700, Prupe.3G098100, Prupe.6G226100, Prupe.7G234800, and Prupe.7G247500, were higher in melting peach fruit than in SH peach fruit during storage. Furthermore, the SH peach fruit softened rapidly after 1-naphthylacetic acid treatment, during which the levels of expression of these seven genes, determined by a quantitative reverse transcription polymerase chain reaction, were strongly induced and upregulated. Thus, these seven genes may play essential roles in regulating peach fruit softening and senescence.

13.
Biotechnol Biofuels Bioprod ; 16(1): 47, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36922896

RESUMO

BACKGROUND: Chlorella sorokiniana FZU60 is a promising lutein producing microalga. A mixotrophy/photoautotrophy two-stage strategy can achieve high biomass concentration at stage 1 and high lutein content at stage 2, leading to excellent lutein production efficiency in C. sorokiniana FZU60. However, the underlying molecular mechanisms are still unclear, restraining the further improvement of lutein production. RESULTS: In this study, physiological and biochemical analysis revealed that photochemical parameters (Fv/Fm and NPQ) and photosynthetic pigments contents increased during the shift from mixotrophy to photoautotrophy, indicating that photosynthesis and photoprotection enhanced. Furthermore, transcriptomic analysis revealed that the glyoxylate cycle and TCA cycle were suppressed after the shift to photoautotrophy, leading to a decreased cell growth rate. However, the gene expression levels of photosynthesis, CO2 fixation, autophagy, and lutein biosynthesis were upregulated at the photoautotrophy stage, demonstrating that microalgal cells could obtain more precursor to synthesize lutein for enhancing photosynthesis and reducing reactive oxygen species. CONCLUSIONS: The findings help to elucidate the molecular mechanisms for high lutein production efficiency of C. sorokiniana FZU60 under the mixotrophy/photoautotrophy strategy, identify key functional genes responsible for lutein biosynthesis, and shed light on further improvement of lutein production by genetic or metabolic engineering in future studies.

14.
Front Med (Lausanne) ; 10: 1273289, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37954552

RESUMO

Background: In nursing homes, elder neglect has come to the forefront. Currently, few studies have examined the impact of personal and organizational factors of geriatric nursing assistants on elder neglect. From the perspective of geriatric nursing assistants, this study aims to explore the current situation and influencing factors of elder neglect in Chinese nursing homes. Methods: A convenience sampling method was used to recruit 412 geriatric nursing assistants from 50 nursing homes in China. Participants were surveyed using a demographic questionnaire, the Elder Neglect Scale for Geriatric Nursing Assistants, the General Self-Efficacy Scale (GSES), and the Proactive Personality Scale (PPS). Spearman correlation analysis and multiple linear regression were used to analyze the factors influencing elder neglect. Results: Geriatric nursing assistants scored a median of 74 out of 85 on the Elder Neglect Scale. Multiple linear regression analyses showed that the main personal factors influencing geriatric nursing assistants' elder neglect were general self-efficacy (ß = 0.312), proactive personality (ß = 0.180), and advanced qualification (ß = 0.084), while the main organizational factors included monthly salary ≤ 1,900 RMB (ß = -0.256), no regular training after induction (ß = -0.253), and the number of days off per month (3-4 days off ß = 0.192, ≥ 5 days off ß = 0.101). Conclusion: Although geriatric nursing assistants are at low levels of elder neglect, it remains a cause for concern. Among the personal factors, geriatric nursing assistants who possessed proactive personalities, high self-efficacy and advanced qualifications, exhibited low levels of elder neglect. Among the organizational factors, those who possessed a high number of days off per month portrayed low levels of elder neglect. Conversely, those who received low monthly salaries and no regular training after induction portrayed high levels of elder neglect. To reduce the risk of elder neglect, nursing homes should give due consideration to candidates' self-efficacy and proactive personality traits when recruiting, and focus on fostering these personality traits in their employees during their work. In addition, strengthening regular training for geriatric nursing assistants, optimizing the salary structure, and arranging rest days in a reasonable manner are also necessary measures.

15.
Artigo em Inglês | MEDLINE | ID: mdl-37022370

RESUMO

Steady-state visual evoked potential (SSVEP)-based brain-computer interfaces (BCIs) have received significant attention owing to their high information transfer rate (ITR) and low training requirements. Previous SSVEP-based BCIs mostly adopt the stationary visual flickers where only a few studies have explored the effect of moving visual flickers on the SSVEP-BCI. In this study, a novel stimulus encoding method based on the simultaneous modulation of luminance and motion was proposed. We adopted the sampled sinusoidal stimulation method to encode the frequencies and phases of stimulus targets. In addition to luminance modulation, at the same time, visual flickers also moved horizontally towards right and left at different frequencies (i.e., 0, 0.2, 0.4, and 0.6 Hz) following a sinusoidal function. Accordingly, a nine-target SSVEP-BCI was built to evaluate the influence of motion modulation on the BCI performance. Filter bank canonical correlation analysis (FBCCA) approach was adopted to identify the stimulus targets. Offline experimental results of 17 subjects revealed that the system performance decreased with the increase of superimposed horizontal periodic motion frequency. Our online experimental results showed that the subjects achieved 85.00 ± 6.77 % and 83.15 ± 9.88 % accuracy for the superimposed horizontal periodic motion frequencies of 0 and 0.2 Hz, respectively. These results verified the feasibility of the proposed systems. In addition, the system with 0.2 Hz horizontal motion frequency provided the best visual experience for subjects. These results indicated that moving visual stimulus can provide an alternative option for SSVEP-BCIs. Furthermore, the proposed paradigm is expected to develop a more comfortable BCI system.

16.
Artigo em Inglês | MEDLINE | ID: mdl-37022899

RESUMO

The brain-computer interfaces (BCIs) based on steady-state visual evoked potential (SSVEP) have been extensively explored due to their advantages in terms of high communication speed and smaller calibration time. The visual stimuli in the low- and medium-frequency ranges are adopted in most of the existing studies for eliciting SSVEPs. However, there is a need to further improve the comfort of these systems. The high-frequency visual stimuli have been used to build BCI systems and are generally considered to significantly improve the visual comfort, but their performance is relatively low. The distinguishability of 16-class SSVEPs encoded by the three frequency ranges, i.e., 31-34.75 Hz with an interval of 0.25 Hz, 31-38.5 Hz with an interval of 0.5 Hz, 31-46 Hz with an interval of 1 Hz, is explored in this study. We compare classification accuracy and information transfer rate (ITR) of the corresponding BCI system. According to the optimized frequency range, this study builds an online 16-target high frequency SSVEP-BCI and verifies the feasibility of the proposed system based on 21 healthy subjects. The BCI based on visual stimuli with the narrowest frequency range, i.e., 31-34.5 Hz, have the highest ITR. Therefore, the narrowest frequency range is adopted to build an online BCI system. An averaged ITR obtained from the online experiment is 153.79 ± 6.39 bits/min. These findings contribute to the development of more efficient and comfortable SSVEP-based BCIs.

17.
Foods ; 12(24)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38137247

RESUMO

The flavour and mouthfeel of peaches are crucial qualities of peach germplasm resources that significantly influence consumer preferences. In this study, we utilized 212 peach germplasm resources from the Nanjing Peach Resource Repository, National Fruit Germplasm facility, Jiangsu Academy of Agricultural Sciences as materials for sensory analysis, electronic nose analysis, and composition analysis via high-performance liquid chromatography (HPLC). In the sensory analysis, we divided 212 peach germplasms into three clusters based on hierarchical cluster analysis (d = 5). No.27, No.151, and No.46 emerged as the most representative of these clusters. The electronic nose was used to conduct an evaluation of the aroma profiles of the 212 peach germplasms, revealing that the primary distinguishing factors of peach aroma can be attributed to three sensors: W1S (methane), W1W (terpenes and organosulfur compounds), and W5S (hydrocarbons and aromatic compounds). The primary differences in the aromatic substances were characterized by sensors W2W (aromatic compounds, sulphur, and chlorine compounds) and W1C (aromatic benzene). The HPLC analysis indicated that the persistence of peach sensory characteristics was positively correlated with acids and sourness and negatively correlated with sweetness and the ratio of sugar to acids. The overall impression of the 212 peach germplasms revealed a negative correlation with acids, while a positive correlation was observed between the overall impression and the ratio of sugar to acids. Therefore, this study substantially contributes to the preliminary screening of the analysed specific characteristics of peach germplasms such as No.27, No.46, No.151, and No.211. These selections may provide valuable information for the potential creation of superior germplasm resources.

18.
Ying Yong Sheng Tai Xue Bao ; 34(6): 1583-1591, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37694421

RESUMO

To screen out suitable herbicides for peach nurseries, we treated the potted seedlings of the peach rootstock 'Nemaguard' with eleven herbicides under recommended doses to investigate the changes of physiological indices and comprehensively evaluate the safety of different herbicides using principal component analysis (PCA). The results showed that soil application of quizalofop-p exhibited no detectable phytotoxicity on rootstock seedlings, while the remaining herbicides generated multiple symptoms, including green loss, wilting, spot, and withering. Starane caused rapid wilting and death, with a 100.0% phytotoxicity index (PI). Soil application of n-(phosphonomethyl)glycine, glufosinate-ammonium, acetochlor, and MCPA-Na showed a PI>65.0%. As compared with the control, all herbicides inhibited leaf area growth to varying degrees, with a 10.0%-56.2% and 5.8%-44.4% reduction in young leaf area and mature leaf area, respectively. All herbicides, except quizalofop-p, increased the electrolyte permeability of leaf and root tip cells by 21.2%-145.0% and 36.9%-291.4%, respectively, and significantly inhibited root growth. The total root length, root surface area, root volume, and the number of root tips significantly decreased by 37.3%-75.3%, 35.7%-83.0%, 44.3%-89.9%, and 42.6%-73.7%, respectively. Although net photosynthetic rate (Pn) and transpiration rate (Tr) of leaves were not significantly affected by quizalofop-p, mesotrione-atrazine, MCPA-Na·bentazone, bensulfuron-methyl·quinclorac, and bensulfuron-methyl·acetochlor, there was significant reduction of 29.6%, 28.9%, 28.4% and 27.9% in Pn and 21.9%, 29.2%, 26.4%, and 19.7% in Tr post soil application of n-(phosphonomethyl)glycine, glufosinate-ammonium, acetochlor, and MCPA-Na. The overall safety ranking of the 11 examined herbicides is as follows: quizalofop-p>bensulfuron-methyl·acetochlor>bensulfuron-methyl·quinclorac>esotrione·atrazine> auizalofop-p·fluoroglycofen>acetochlor>MCPA-Na·bentazone>MCPA-Na>n-(phosphonomethyl)glycine>glufosinate-ammonium>sterane.


Assuntos
Ácido 2-Metil-4-clorofenoxiacético , Atrazina , Herbicidas , Prunus persica , Herbicidas/toxicidade , Plântula
19.
Clin Med Insights Oncol ; 17: 11795549231201128, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37823009

RESUMO

Background: Numerous studies have shown that polymorphisms in the diabetes susceptibility gene, insulin-like growth factor 2mRNA-binding protein 2 (IGF2BP2), are associated with the occurrence and development of various malignant tumors; however, their correlation with the onset of diffuse large B-cell lymphoma (DLBCL) is still unknown. Therefore, this study aimed to explore whether IGF2BP2 polymorphisms increase the risk of developing DLBCL. Methods: This study included 295 DLBCL patients and 331 healthy individuals. Peripheral blood was collected, and polymerase chain reaction-ligase detection reaction (PCR-LDR) was used to detect IGF2BP2 gene polymorphisms. Logistic regression was used to assess the association between IGF2BP2 polymorphism and the risk of DLBCL, adjusted for age, sex, and body mass index (BMI). P < .05 indicated statistical significance. Results: The rs4402960 polymorphism in the IGF2BP2 gene was associated with the occurrence and development of DLBCL. After adjusting for age, sex, and BMI, GT (odd ratio [OR] = 1.54; 95% confidence interval [CI] = 1.08-2.19; P = .016), TT (OR = 2.00; 95% CI = 1.09-3.68; P = .026), and T genotype carrying (GT + TT) (OR = 1.62; 95% CI = 1.17-2.25; P = .004) significantly increased the risk of DLBCL. This study also found that the polymorphism rs1470579 was related to the development of DLBCL. After adjusting for age, sex, and BMI, AC (OR = 1.55; 95% CI = 1.11-2.17; P = .010), CC (OR = 2.18; 95% CI = 1.17-4.06; P = .014), and C genotype carrying (AC + CC) (OR = 1.64; 95% CI = 1.19-2.26; P = .002) significantly increased the risk of DLBCL. Conclusions: Our study found that polymorphism in the IGF2BP2 gene was associated with an increased risk of developing DLBCL.

20.
J Exp Clin Cancer Res ; 42(1): 192, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37537587

RESUMO

BACKGROUND: Platinum-drugs based chemotherapy in clinic increases the potency of tumor cells to produce M2 macrophages, thus leading to poor anti-metastatic activity and immunosuppression. Lysosome metabolism is critical for cancer cell migration and invasion, but how it promotes antitumor immunity in tumours and macrophages is poorly understood and the underlying mechanisms are elusive. The present study aimed to explore a synergistic strategy to dismantle the immunosuppressive microenvironment of tumours and metallodrugs discovery by using the herent metabolic plasticity. METHODS: Naphplatin was prepared by coordinating an active alkaline moiety to cisplatin, which can regulate the lysosomal functions. Colorectal carcinoma cells were selected to perform the in vivo biological assays. Blood, tumour and spleen tissues were collected and analyzed by flow cytometry to further explore the relationship between anti-tumour activity and immune cells. Transformations of bone marrow derived macrophage (BMDM) and M2-BMDM to the M1 phenotype was confirmed after treatment with naphplatin. The key mechanisms of lysosome-mediated mucolipin-1(Mcoln1) and mitogen-activated protein kinase (MAPK) activation in M2 macrophage polarization have been unveiled. RNA sequencing (RNA-seq) was used to further explore the key mechanism underlying high-mobility group box 1(HMGB1)-mediated Cathepsin L(CTSL)-lysosome function blockade. RESULTS: We demonstrated that naphplatin induces divergent lysosomal metabolic programs and reprograms macrophages in tumor cells to terminate the vicious tumour-associated macrophages (TAMs)-MDSCs-Treg triangle. Mechanistically, macrophages treated with naphplatin cause lysosome metabolic activation by triggering Ca2+ release via Mcoln1, which induces the activation of p38 and nuclear factor-κB (NF-κB) and finally results in polarizing M2 macrophages. In contrast, HMGB1-mediated lysosome metabolic blockade in cancer cells is strongly linked to antitumor effects by promoting cytoplasmic translocation of HMGB1. CONCLUSIONS: This study reveals the crucial strategies of macrophage-based metallodrugs discovery that are able to treat both immunologically "hot" and "cold" cancers. Different from traditional platinum-based antitumour drugs by inhibition of DNAs, we also deliver a strong antitumour strategy by targeting lysosome to induce divergent metabolic programs in macrophages and tumours for cancer immunotherapy.


Assuntos
Antineoplásicos , Proteína HMGB1 , Neoplasias , Humanos , Proteína HMGB1/metabolismo , Macrófagos/metabolismo , Neoplasias/patologia , Imunoterapia , Antineoplásicos/farmacologia , Lisossomos/metabolismo , Microambiente Tumoral
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