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1.
Front Pharmacol ; 15: 1371890, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948467

RESUMO

Introduction: Rhubarb is a frequently used and beneficial traditional Chinese medicine. Wild resources of these plants are constantly being depleted, meaning that rhubarb products have been subjected to an unparalleled level of adulteration. Consequentially, reliable technology is urgently required to verify the authenticity of rhubarb raw materials and commercial botanical drugs. Methods: In this study, the barcode-DNA high-resolution melting (Bar-HRM) method was applied to characterize 63 rhubarb samples (five Polygonaceae species: Rheum tanguticum, Rh. palmatum, Rh. officinale, Rumex japonicus and Ru. sp.) and distinguish the rhubarb contents of 24 traditional Chinese patent medicine (TCPM) samples. Three markers, namely ITS2, rbcL and psbA-trnH, were tested to assess the candidate DNA barcodes for their effectiveness in distinguishing rhubarb from its adulterants. A segment from ITS2 was selected as the most suitable mini-barcode to identify the botanical drug rhubarb in TCPMs. Then, rhubarbs and TCPM samples were subjected to HRM analysis based on the ITS2 barcode. Results: Among the tested barcoding loci, ITS2 displayed abundant sites of variation and was effective in identifying Polygonaceae species and their botanical origins. HRM analysis based on the ITS2 mini-barcode region successfully distinguished the authenticity of five Polygonaceae species and eight batches of TCPMs. Of the 18 TCPM samples, 66.7 % (12 samples) were identified as containing Rh. tanguticum or Rh. officinale. However, 33.3 % were shown to consist of adulterants. Conclusions: These results demonstrated that DNA barcoding combined with HRM is a specific, suitable and powerful approach for identifying rhubarb species and TCPMs, which is crucial to guaranteeing the security of medicinal plants being traded internationally.

2.
Foods ; 13(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38790767

RESUMO

Dendrobium officinale is a valuable traditional Chinese herbal plant that is both medicinal and edible. However, the yield of wild Dendrobium officinale is limited. Adverse stress affects the growth, development, and yield of plants, among which low temperature is the primary limiting factor for introducing Dendrobium officinale to high-latitude areas and expanding the planting area. Therefore, this study aims to explore the variations in growth ability, cold resistance, and contents of bioactive compounds among different Dendrobium officinale strains. Four strains of Dendrobium officinale were selected as experimental materials and were subjected to low-temperature stress (4 °C). The agronomic traits, physiological indices, as well as the expressions of cold resistance-related genes (HSP70, DcPP2C5, DoCDPK1, and DoCDPK6) in the roots and leaves of Dendrobium officinale, were determined. The contents of bioactive compounds, including polysaccharides, flavonoids, and phenols were also measured. Compared with the other strains, Xianju had the highest seed germination and transplantation-related survival rates. Under low-temperature stress, Xianju exhibited the strongest cold resistance ability, as revealed by the changes in water contents, chlorophyll levels, electrical conductivities, enzyme activities, and expressions of the cold resistance-related genes. Additionally, the polysaccharide content of Xianju increased the most, while the stem flavonoid and leaf phenol contents were elevated in all four strains under cold treatment. Therefore, selecting excellent performing strains is expected to expand the planting area, improve the yield, and increase the economic benefits of Dendrobium officinale in high latitude areas with lower temperatures.

3.
Foods ; 12(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38002182

RESUMO

(1) Background: Rapid and accurate determination of the content of the chemical dye Auramine O(AO) in traditional Chinese medicines (TCMs) is critical for controlling the quality of TCMs. (2) Methods: Firstly, various models were developed to detect AO content in Dendrobium officinale (D. officinale). Then, the detection of AO content in Saffron and Curcuma using the D. officinale training set as a calibration model. Finally, Saffron and Curcuma samples were added to the training set of D. officinale to predict the AO content in Saffron and Curcuma using secondary wavelength screening. (3) Results: The results show that the sparrow search algorithm (SSA)-backpropagation (BP) neural network (SSA-BP) model can accurately predict AO content in D. officinale, with Rp2 = 0.962, and RMSEP = 0.080 mg/mL. Some Curcuma samples and Saffron samples were added to the training set and after the secondary feature wavelength screening: The Support Vector Machines (SVM) quantitative model predicted Rp2 fluctuated in the range of 0.780 ± 0.035 for the content of AO in Saffron when 579, 781, 1195, 1363, 1440, 1553 and 1657 cm-1 were selected as characteristic wavelengths; the Partial Least Squares Regression (PLSR) model predicted Rp2 fluctuated in the range of 0.500 ± 0.035 for the content of AO in Curcuma when 579, 811, 1195, 1353, 1440, 1553 and 1635 cm-1 were selected as the characteristic wavelengths. The robustness and generalization performance of the model were improved. (4) Conclusion: In this study, it has been discovered that the combination of surface-enhanced Raman spectroscopy (SERS) and machine learning algorithms can effectively and promptly detect the content of AO in various types of TCMs.

4.
J Alzheimers Dis Rep ; 7(1): 1247-1257, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025799

RESUMO

Background: Alzheimer's disease (AD) is a multi-gene inherited disease, and apolipoprotein E (APOE) ɛ4 is a strong risk factor. Other genetic factors are important but limited. Objective: This study aimed to investigate the relationship between 17 single-nucleotide polymorphisms (SNPs) and AD in the Southern Chinese populations. Methods: We recruited 242 AD patients and 208 controls. The SNaPshot technique was used to detect the SNPs. Results: Adjusted for sex and age, we found rs6572869 (FERMT2), rs11604680 (CELF1), and rs1317149 (CELF1) were associated with AD risk in the dominant (rs6572869: p = 0.022, OR = 1.55; rs11604680: p = 0.007, OR = 1.68; rs1317149: p = 0.033, OR = 1.50) and overdominant models (rs6572869: p = 0.001, OR = 1.96; rs11604680: p = 0.002, OR = 1.82; rs1317149: p = 0.003, OR = 1.80). rs9898218 (COPI) was associated with AD risk in the overdominant model (p = 0.004, OR = 1.81). Further, rs2741342 (CHRNA2) was associated with AD protection in the dominant (p = 0.002, OR = 0.5) and additive models (p = 0.002, OR = 0.64). Mutations in rs10742814 (CELF1), rs11039280 (CELF1), and rs3752242 (ABCA7) contributed to AD protection. Among them, rs10742814 (CELF1), rs3752242 (ABCA7), and rs11039280 (CELF1) were more significantly associated with AD carrying APOE ɛ4, whereas rs1317149 (CELF1) showed an opposite trend. Interestingly, rs4147912 (ABCA7) and rs2516049 (HLA-DRB1) were identified to be relevant with AD carrying APOE ɛ4. Using expression quantitative trait locus analysis, we found polymorphisms in CELF1 (rs10742814 and rs11039280), ABCA7 (rs4147912), HLA-DRB1 (rs2516049), and ADGRF4 (rs1109581) correlated with their corresponding gene expression in the brain. Conclusions: We identified four risk and four protective SNPs associated with AD in the Southern Chinese population, with different correlations between APOE ɛ4 carriers and non-carriers. rs4147912 (ABCA7) and rs2516049 (HLA-DRB1) were associated with AD carrying APOE ɛ4.

5.
J Agric Food Chem ; 71(43): 15895-15907, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862148

RESUMO

Plant height is an important agronomic trait that is closely associated with crop yield and quality. Gibberellins (GAs), a class of highly efficient plant growth regulators, play key roles in regulating plant height. Increasing reports indicate that transcriptional regulation is a major point of regulation of the GA pathways. Although substantial knowledge has been gained regarding GA biosynthetic and signaling pathways, important factors contributing to the regulatory mechanisms homeostatically controlling GA levels remain to be elucidated. Here, we provide an overview of current knowledge regarding the regulatory network involving transcription factors, noncoding RNAs, and histone modifications involved in GA pathways. We also discuss the mechanisms of interaction between GAs and other hormones in plant height development. Finally, future directions for applying knowledge of the GA hormone in crop breeding are described.


Assuntos
Giberelinas , Melhoramento Vegetal , Giberelinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Plantas/metabolismo , Homeostase , Regulação da Expressão Gênica de Plantas
6.
Int J Mol Sci ; 24(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36901809

RESUMO

Cadmium (Cd) is a non-essential heavy metal with high toxicity to plants. Plants have acquired specialized mechanisms to sense, transport, and detoxify Cd. Recent studies have identified many transporters involved in Cd uptake, transport, and detoxification. However, the complex transcriptional regulatory networks involved in Cd response remain to be elucidated. Here, we provide an overview of current knowledge regarding transcriptional regulatory networks and post-translational regulation of the transcription factors involved in Cd response. An increasing number of reports indicate that epigenetic regulation and long non-coding and small RNAs are important in Cd-induced transcriptional responses. Several kinases play important roles in Cd signaling that activate transcriptional cascades. We also discuss the perspectives to reduce grain Cd content and improve crop tolerance to Cd stress, which provides a theoretical reference for food safety and the future research of plant varieties with low Cd accumulation.


Assuntos
Cádmio , Metais Pesados , Cádmio/metabolismo , Epigênese Genética , Plantas/metabolismo , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/metabolismo
7.
Front Bioeng Biotechnol ; 11: 1112338, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36741747

RESUMO

The poor solubility of numerous drugs pose a long-existing challenge to the researchers in the fields of pharmaceutics, bioengineering and biotechnology. Many "top-down" and "bottom-up" nano fabrication methods have been exploited to provide solutions for this issue. In this study, a combination strategy of top-down process (electrospinning) and bottom-up (self-emulsifying) was demonstrated to be useful for enhancing the dissolution of a typical poorly water-soluble anticancer model drug (paclitaxel, PTX). With polyvinylpyrrolidone (PVP K90) as the filament-forming matrix and drug carrier, polyoxyethylene castor oil (PCO) as emulsifier, and triglyceride (TG) as oil phase, Both a single-fluid blending process and a coaxial process were utilized to prepare medicated nanofibers. Scanning electron microscope and transmission electron microscope (TEM) results clearly demonstrated the morphology and inner structures of the nanofibers. The lipid nanoparticles of emulsions after self-emulsification were also assessed through TEM. The encapsulation efficiency (EE) and in vitro dissolution tests demonstrated that the cores-shell nanofibers could provide a better self-emulsifying process int terms of a higher EE and a better drug sustained release profile. Meanwhile, an increase of sheath fluid rate could benefit an even better results, suggesting a clear process-property-performance relationship. The protocols reported here pave anew way for effective oral delivery of poorly water-soluble drug.

8.
Front Plant Sci ; 14: 1068296, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36798712

RESUMO

Plants are frequently subjected to a broad spectrum of abiotic stresses including drought, salinity and extreme temperatures and have evolved both common and stress-specific responses to promote fitness and survival. Understanding the components and mechanisms that underlie both common and stress-specific responses can enable development of crop plants tolerant to different stresses. Here, we report a rice heat stress-tolerant 1 (hst1) mutant with increased heat tolerance. HST1 encodes the DST transcription factor, which also regulates drought and salinity tolerance. Increased heat tolerance of hst1 was associated with suppressed expression of reactive oxygen species (ROS)-scavenging peroxidases and increased ROS levels, which reduced water loss by decreasing stomatal aperture under heat stress. In addition, increased ROS levels enhanced expression of genes encoding heat shock protein (HSPs) including HSP80, HSP74, HSP58 and small HSPs. HSPs promote stabilization of proteins and protein refolding under heat stress and accordingly mutation of HST1 also improved reproductive traits including pollen viability and seed setting under high temperature. These results broaden the negative roles of DST in abiotic stress tolerance and provide important new insights into DST-regulated tolerance to diverse abiotic stresses through both shared and stress-specific mechanisms.

9.
Int J Mol Sci ; 23(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36233272

RESUMO

Global warming is an environmental problem that cannot be ignored. High temperatures seriously affect the normal growth and development of plants, and threaten the development of agriculture and the distribution and survival of species at risk. Plants have evolved complex but efficient mechanisms for sensing and responding to high temperatures, which involve the activation of numerous functional proteins, regulatory proteins, and non-coding RNAs. These mechanisms consist of large regulatory networks that regulate protein and RNA structure and stability, induce Ca2+ and hormone signal transduction, mediate sucrose and water transport, activate antioxidant defense, and maintain other normal metabolic pathways. This article reviews recent research results on the molecular mechanisms of plant response to high temperatures, highlighting future directions or strategies for promoting plant heat tolerance, thereby helping to identify the regulatory mechanisms of heat stress responses in plants.


Assuntos
Redes Reguladoras de Genes , Proteínas de Plantas , Antioxidantes/metabolismo , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico/genética , Hormônios/metabolismo , Proteínas de Plantas/metabolismo , Plantas/genética , Plantas/metabolismo , RNA/metabolismo , Estresse Fisiológico/genética , Sacarose/metabolismo , Água/metabolismo
10.
J Agric Food Chem ; 70(28): 8513-8522, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35816106

RESUMO

Soil heavy-metal pollution leads to excessive heavy metals in rice and other food crops, which has caused serious impacts on the ecological environment and on human health. In recent years, environmental friendly treatment methods that reduce the bioavailability of heavy metals in soil by soil microorganisms improving the tolerance of heavy metals in rice and reducing the transfer of heavy metals from the roots to the above-ground parts of rice have attracted much attention. This paper reviews the role and mechanism of soil microorganisms in alleviating heavy-metal stress in rice at home and abroad in recent years. At present, microorganisms tolerant to heavy metals mainly include bacteria and fungi, and their mechanisms include the adsorption of heavy metals by microorganisms, the secretion of growth-promoting substances (growth hormone, ACC deaminase, IAA), changing the physical and chemical properties of the soil and the composition of the microbial community, changing the transport mode of heavy metals in soil, the improvement of the antioxidant capacity of rice, etc. Hence, soil microorganisms have good application value and prospects in rice and other crops. However, the vast majority of current research focuses on a single strain, the screening principles of strains are limited, the pathogenicities of the strains have not been evaluated, and there are still few field experiments under natural conditions. In the future, we should strengthen the action of soil microorganisms on rice in response to the above problems in heavy metals, to better promote the microbial remediation technology.


Assuntos
Metais Pesados , Microbiota , Oryza , Poluentes do Solo , China , Produtos Agrícolas , Humanos , Metais Pesados/análise , Metais Pesados/toxicidade , Oryza/fisiologia , Solo/química , Poluentes do Solo/análise
11.
Stem Cell Res ; 63: 102869, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35853414

RESUMO

IPSCs have great potential value in cell replacement therapy, pathogenesis research, screening for new drugs, and treatment of clinical disease. An 82-year-old woman with mild cognitive impairment (MCI) and her unaffected child donated their peripheral blood mononuclear cells (PBMC). Their PBMCs were reprogrammed using human OKSM transcription factors (SOX2, OCT3/4, KLF4 and C-MYC) via a non-integrated complementary vector system. In the newly developed hiPSC series SIAISi019-A and SIAISi020-A, immunocytochemistry and the ability to spontaneously differentiate into 3 germ layers in vitro confirmed the pluripotency of transgene-free iPSCs. And their karyotypes were normal.


Assuntos
Disfunção Cognitiva , Células-Tronco Pluripotentes Induzidas , Idoso de 80 Anos ou mais , Diferenciação Celular , Criança , China , Disfunção Cognitiva/genética , Feminino , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucócitos Mononucleares
12.
Stem Cell Res ; 63: 102866, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35843023

RESUMO

A 71-year-old Han male from China contributed peripheral blood mononuclear cells (PBMCs). Non-integrative Sendai viral vectors containing reprogramming factors OCT4, KLF4, SOX2 and C-MYC were used to reprogram PBMCs. Pluripotency makers confirmed the pluripotency of transgene-free induced pluripotent stem cell (iPSC). The ability of iPSC to spontaneously differentiate three germ layers in vitro confirmed the pluripotency of iPSC. The iPSC line displayed a normal karyotype. The newly generated human iPSC SIAISi021-A can be used for studying further disease mechanisms of Alzheimer's Disease (AD).


Assuntos
Doença de Alzheimer , Células-Tronco Pluripotentes Induzidas , Idoso , Alelos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Apolipoproteína E4/genética , Apolipoproteína E4/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular , Células Cultivadas , Reprogramação Celular , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucócitos Mononucleares , Masculino
13.
Curr Alzheimer Res ; 18(6): 513-522, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34598666

RESUMO

OBJECTIVE: Numerous electroencephalography (EEG) studies focus on the alteration of electrical activity in patients with Alzheimer's Disease (AD), but there are no consistent results especially regarding functional connectivity. We supposed that the weighted Phase Lag Index (w- PLI), as phase-based measures of functional connectivity, may be used as an auxiliary diagnostic method for AD. METHODS: We enrolled 30 patients with AD, 30 patients with Mild Cognitive Impairment (MCI), and 30 Healthy Controls (HC). EEGs were recorded in all participants at baseline during relaxed wakefulness. Following EEG preprocessing, Power Spectral Density (PSD) and wPLI parameters were determined to further analyze whether they were correlated to cognitive scores. RESULTS: In the patients with AD, the increased PSD in theta band was presented compared with MCI and HC groups, which was associated with disturbances of the directional, computational, and delayed memory capacity. Furthermore, the wPLI revealed a distinctly lower connection strength between frontal and distant areas in the delta band and a higher connection strength of the central and temporo-occipital region in the theta band for AD patients. Moreover,we found a significant negative correlation between theta functional connectivity and cognitive scores. CONCLUSION: Increased theta PSD and decreased delta wPLI may be one of the earliest changes in AD and associated with disease severity. The parameter wPLI is a novel measurement of phase synchronization and has potentials in understanding underlying functional connectivity and aiding in the diagnostics of AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Eletroencefalografia/instrumentação , Idoso , Encéfalo/fisiopatologia , Ritmo Delta , Feminino , Humanos , Masculino , Testes Neuropsicológicos/estatística & dados numéricos , Ritmo Teta
14.
Sheng Wu Gong Cheng Xue Bao ; 37(1): 242-252, 2021 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-33501805

RESUMO

To screen the available tomato pollution-safe cultivar varieties and reduce the potential food safety risks in Cd-polluted areas, the differences of Cd accumulation in different tomato (Solanum lycopersicum) varieties in southern China were studied by soil culture and hydroponic experiments. Firstly, the high and low accumulation varieties were selected from 25 tomato varieties under 2.94 mg/kg Cd stress by soil culture test, and then the responses of high and low accumulation tomato varieties to Cd stress were determined by hydroponic experiments. The results of soil culture test show that under 2.94 mg/kg Cd stress, there were significant differences in plant height, total biomass and yield among 25 tomato cultivars, and the Cd contents of fruits of all 25 tomato cultivars exceeded the highest limit value (0.05 mg/kg) of CAC (Codex alimentarius commission). Through cluster analysis, 7, 4 and 14 varieties accumulating relatively high, medium, and low concentrations of Cd in the fruits were screened, among which the highest, the lowest, and the average Cd contents in the fruits were 3.06 mg/kg DW, 1.47 mg/kg DW, and 2.21 mg/kg DW, respectively. The results of hydroponic experiment show that under the same concentration of Cd stress, Qiantangxuri F1, a high Cd accumulating variety, absorbed Cd faster, accumulated more Cd, used shorter oxidative stress response time and had stronger tolerance to Cd than Zhefen 3053, a low Cd accumulating variety. The typical high and low Cd accumulating varieties can provide a reference for agricultural production in heavy metal polluted areas and the development of molecular-assisted breeding methods of PSC. At present, cultivating low Cd accumulating PSC varieties and dynamic monitoring of Cd contents in tomato fruits are feasible methods in medium and light Cd-polluted areas.


Assuntos
Poluentes do Solo , Solanum lycopersicum , Antioxidantes , Cádmio/análise , Cádmio/toxicidade , China , Melhoramento Vegetal , Raízes de Plantas/química , Poluentes do Solo/toxicidade
15.
J Agric Food Chem ; 69(2): 794-804, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33401907

RESUMO

Pufferfish is a traditional, delicious dish in Asia. However, eating wild or improperly processed pufferfish causes serious poisoning. This study aimed to exploit the high-resolution melting (HRM) method for authenticating four species of Takifugu pufferfish (Takifugu xanthopterus, T. fasciatus, T. flavidus, and T. rubripes). Candidate DNA barcodes, including the cytochrome c oxidase subunit I (COI), cytochrome oxidase b (Cytb), and the control region (D-loop), were analyzed, with COI selected as the optimal DNA barcode. An HRM method was developed to identify 57 commercial fish samples in China, including 33 commercial pufferfish products and 24 unlabeled fish products. The findings revealed that the pufferfish products were T. rubripes or T. fasciatus, and four T. xanthopterus samples were detected in unlabeled fish products. These results showed that DNA barcode coupled with HRM analysis was a rapid and efficient tool to identify pufferfish, which might aid in the prevention of consumer fraud or mislabeling of fish products.


Assuntos
DNA/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Peixes/genética , Técnicas Genéticas , Takifugu/genética , Animais , China , DNA/química , Análise Discriminante , Takifugu/classificação , Temperatura de Transição
16.
Ecotoxicol Environ Saf ; 207: 111198, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32905932

RESUMO

Cd pollution in farmland is becoming a serious problem because it affects the safety of rice production and human health. Salicylic acid (SA) plays crucial roles in plant development and mediates plant responses to biotic and abiotic stress. This study assessed the molecular and physiological mechanisms of SA spraying effects on Cd tolerance and Cd accumulation in rice. Spraying of 0.1 mM SA had no great effect on the agronomic traits of rice, but significantly decreased Cd accumulation in rice grains, and SA spraying increased the Cd contents in leaves (only at the mature stage) and decreased the Cd contents in panicles (only at the filling and mature stage), but had no evident impact on the Cd content of other tissues and other growth stages. SA spraying reduced Cd accumulation in rice grains by promoting the deposition and fixation of Cd in the cell wall of leaves, thus preventing Cd being transferred from leaves to rice grains at the filling stage. SA spraying also decreased Cd toxicity by reducing H2O2 and MDA accumulation and increasing the chlorophyll content in rice leaves. Furthermore, SA spraying remarkably decreased Cd accumulation in rice grains by modulating the expression level of the genes associated with Cd translocation and accumulation to control the Cd accumulation in rice. Hence, SA spraying reduced the inhibition of Cd on the plant height caused by Cd and increased the dry weight of shoots in the vegetative growth period of rice seedlings, and it reduced Cd transport from leaves to grains, thus reducing Cd content in rice. These findings provide a novel perspective and a new method for reducing Cd accumulation in rice.


Assuntos
Cádmio/toxicidade , Oryza/metabolismo , Substâncias Protetoras/farmacologia , Ácido Salicílico/farmacologia , Poluentes do Solo/toxicidade , Cádmio/metabolismo , Clorofila/metabolismo , Poluição Ambiental , Humanos , Peróxido de Hidrogênio/metabolismo , Folhas de Planta/metabolismo , Plântula/efeitos dos fármacos , Poluentes do Solo/metabolismo , Estresse Fisiológico/efeitos dos fármacos
17.
Chemosphere ; 263: 128034, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297052

RESUMO

Cadmium (Cd) contamination, which poses a serious threat to human health, has been recognized as a major threat to the agricultural system and crop production. Salicylic acid (SA) is a signaling molecule that plays an important role in against Cd toxicity. Previously, we found that spraying rice with SA could reduce the Cd accumulation in rice grains grown in Cd-contaminated soil. In this study, we studied the specific mechanism of SA spray on reducing Cd accumulation in rice grain. The results showed that treatment with SA could alleviate Cd toxicity in rice by increasing the activities of antioxidant enzymes that reduce hydrogen peroxide (H2O2) accumulation, but not by changing the pH, or total or available Cd of the soil. The key factor by which SA treatment reduced Cd accumulation in rice grains was by decreasing the Cd content in rice leaves at the flowering stage. This indicated that SA could modulate the Cd accumulation in shoots, reducing the Cd translocation to rice grains. Furthermore, SA could increase the H2O2 content, activating the SA-signaling pathway and modulating the expression levels of Cd transporters (OsLCT1 and OsLCD) in rice leaves to increase Cd tolerance and reduce Cd accumulation in the rice grain. Thus, spraying rice with SA may be effective measure to cope with Cd contamination in paddy soils.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Cádmio/toxicidade , Grão Comestível/química , Humanos , Peróxido de Hidrogênio , Ácido Salicílico , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
18.
J Agric Food Chem ; 68(41): 11320-11326, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32870674

RESUMO

Heat stress is a major abiotic stress that significantly affects plant growth and productivity. Plants have, however, evolved complex adaptive mechanisms to cope with heat stress. MicroRNAs (miRNAs) are important molecules that regulate gene expression through the post-transcriptional degradation of target mRNA molecules or by repressing translation. Plant miRNAs play essential roles in development and a variety of stress responses. Recent advances in high-throughput sequencing technologies have enabled the identification and characterization of an increasing number of heat-responsive miRNAs in diverse plant species. Heat-regulated miRNAs combined with their target genes constitute large regulatory networks that control various metabolic pathways, including protein refolding, antioxidant defense, maintenance of photosynthetic systems, protection of reproductive tissues, regulation of flowering time, and miRNA biogenesis. In this review, we summarize the information acquired to date about the significance of plant miRNAs and their target genes in heat stress tolerance, thereby helping to identify the regulatory mechanisms that underlie heat stress responses in plants.


Assuntos
Resposta ao Choque Térmico , MicroRNAs/metabolismo , RNA de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Fenômenos Fisiológicos Vegetais , Plantas/genética , RNA de Plantas/genética
19.
Polymers (Basel) ; 12(9)2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32906728

RESUMO

In this study, a new modified triaxial electrospinning is implemented to generate an Eudragit S100 (ES100)-based core-shell structural nanofiber (CSF), which is loaded with aspirin. The CSFs have a straight line morphology with a smooth surface, an estimated average diameter of 740 ± 110 nm, and a clear core-shell structure with a shell thickness of 65 nm, as disclosed by the scanning electron microscopy and transmission electron microscopy results. Compared to the monolithic composite nanofibers (MCFs) produced using traditional blended single-fluid electrospinning, aspirin presented in both of them amorously owing to their good compatibility. The CSFs showed considerable advantages over the MCFs in providing the desired drug-controlled-release profiles, although both of them released the drug in an erosion mechanism. The former furnished a longer time period of time-delayed-release and a smaller portion released during the first two-hour acid condition for protecting the stomach membranes, and also showed a longer time period of aspirin-extended-release for avoiding possible drug overdose. The present protocols provide a polymer-based process-nanostructure-performance relationship to optimize the reasonable delivery of aspirin.

20.
Oncol Lett ; 20(2): 1193-1200, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32724359

RESUMO

Patient screening is important for early diagnosis of colorectal cancer (CRC). The present study aimed to compare the multitarget stool DNA (mt-sDNA) test with the fecal occult blood test (FOBT) for CRC screening. A total of 151 individuals were screened using colonoscopy, mt-sDNA and FOBT for the detection of CRC and adenoma. The results of the mt-sDNA test and FOBT were compared with colonoscopy to examine their sensitivity and specificity. Subsequently, the sensitivity and specificity of the mt-sDNA test were compared with those of FOBT in CRC and large adenoma. Stool samples were collected from patients with CRC (n=50) or large adenoma (n=51), as well as from normal controls (n=50). The mt-sDNA test outperformed FOBT in detecting CRC with a sensitivity of 90.0% (45/50) vs. 42.0% (21/50), advanced adenoma with a sensitivity of 70.6% (36/51) vs. 19.6% (10/51), stage I-III CRC with a sensitivity of 91.9% (34/37) vs. 29.7% (11/37), and stage IV CRC with a sensitivity of 84.6% (11/13) vs. 76.9% (10/13). In addition, the mt-sDNA test exhibited a specificity of 94.0% (47/50) in detecting CRC, which was superior to FOBT with a specificity of 90.0% (45/50). Therefore, the mt-sDNA test may have higher sensitivity and specificity compared with FOBT in diagnosing both CRC and advanced adenoma.

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