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1.
ACS Omega ; 8(36): 32372-32381, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37720732

RESUMO

Cadmium (Cd) is a toxic heavy metal that significantly threatens plants and the environment. Its toxicity in plants can result in various adverse effects, including reduced growth, altered metabolism, and cell damage. Cadmium can also interfere with nutrient uptake, particularly zinc (Zn), leading to Zn deficiency and further exacerbating Cd toxicity. On the other hand, foliar application of zinc might be a useful strategy to mitigate cadmium (Cd) toxicity in plants. Hence, a pot experiment was conducted with three replications. The wheat plants were treated with various concentrations of Zn as a foliar spray (control, 0.1, 0.2, 0.4, and 0.5%) in Cd-spiked soil in pots. The results showed that foliar use of Zn at 0.4 or 0.5% resulted in higher plant height, grain yield, and dry matter yield than the control group. Using Zn as foliar spray enriched shoot and grain Zn content while reducing Cd content in the shoot and grain. The leaf's electrolyte leakage (EL) decreased by 15.4, 29.8, 40.7, and 45.9% in the Zn 0.1%, Zn 0.2%, Zn 0.4%, and Zn 0.5% treatments, respectively, compared to the control treatment. Regarding superoxide dismutase (SOD) activity, Zn 0.5% treatment showed a decrease of 42.9% over control. Specifically, the Zn 0.1% showed a 27.2%, Zn 0.2% showed a 56.8%, Zn 0.4% showed a 91.1%, and Zn 0.5% showed a 133.7% increase in total chlorophyll content than control. Based on the results, it is recommended that 0.4% Zn solution may be used for foliar application for enhancing crop productivity and Zn concentration in plants under high Cd stress. Additionally, continued research on the mechanisms of cadmium uptake, transport, and detoxification in plants may lead to the identification of new targets for intervention.

2.
RSC Adv ; 13(20): 13940-13946, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37181511

RESUMO

Human papillomavirus type 16 (HPV16), one of the high-risk types, is responsible for 53% of cervical cancers. The development of an early diagnostic approach with high sensitivity, low-cost, point-of-care testing (POCT) for HPV16 is urgent. In our work, a novel dual-functional AuPt nanoalloy-based lateral flow nucleic acid biosensor (AuPt nanoalloy-based LFNAB) was established with excellent sensitivity for detecting HPV16 DNA for the first time. The AuPt nanoalloy particles were prepared by a one-step reduction method, which was simple, rapid, and green. The AuPt nanoalloy particles retained the performance of initial Au nanoparticles owing to the catalytic activity enabled by Pt. Such dual-functionalities offered two kinds of detection alternatives (i.e., normal mode and amplification mode, respectively). The former is produced just by the black color from the AuPt nanoalloy material itself, and the latter is more color sensitive from its superior catalytic activity. The optimized AuPt nanoalloy-based LFNAB exhibited satisfactory quantitative ability in detecting the target HPV16 DNA in the range of 5-200 pM with a LOD of 0.8 pM at the "amplification mode". The proposed dual-functional AuPt nanoalloy-based LFNAB displayed great potential and promising opportunity in POCT clinical diagnostics.

3.
Anal Chim Acta ; 1260: 341205, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37121654

RESUMO

A rapid and ultrasensitive lateral flow biosensor was developed, which based on gold and platinum nanoparticles-decorated carbon nanotubes (PtAu@CNTs) nanocomposite catalytic chromogenic signal amplification strategy for the detection of nucleic acid. Independent platinum and gold nanoparticles modified functional carbon nanotubes (PtAu@CNTs) were prepared by in-situ reduction. Sandwich-type hybridization reaction occurred between PtAu@CNTs-labeled DNA probe, target DNA and Biotin-modified DNA probes, which was captured on test zone of the strip. Accumulation of PtAu@CNTs nano-labels formed a characteristic colored band. After systematic optimization and catalytic chromogen, the naked eye detection limit of PtAu@CNTs-LFA was about 2 pM, and the theoretical detection limit of target DNA is calculated to be 0.43 pM according to the standard curve. The results indicates a rapid, sensitive and specific methods for DNA detection in biological samples, showing great promise for biomedical diagnosis in some malignant diseases in clinical application.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanotubos de Carbono , Ácidos Nucleicos , Ouro , Platina , DNA/genética , Técnicas Biossensoriais/métodos , Sondas de DNA/genética , Limite de Detecção
4.
Polymers (Basel) ; 14(14)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35890551

RESUMO

Tea polysaccharide (TPS) is the second most abundant ingredient in tea following tea polyphenols. As a complex polysaccharide, TPS has a complex chemical structure and a variety of bioactivities, such as anti-oxidation, hypoglycemia, hypolipidemic, immune regulation, and anti-tumor. Additionally, it shows excellent development and application prospects in food, cosmetics, and medical and health care products. However, numerous studies have shown that the bioactivity of TPS is closely related to its sources, processing methods, and extraction methods. Therefore, the authors of this paper reviewed the relevant recent research and conducted a comprehensive and systematic review of the extraction methods, physicochemical properties, and bioactivities of TPS to strengthen the understanding and exploration of the bioactivities of TPS. This review provides a reference for preparing and developing functional TPS products.

5.
Front Plant Sci ; 13: 876545, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35498658

RESUMO

Dynamic regulation of phytohormone levels is pivotal for plant adaptation to harmful conditions. It is increasingly evidenced that endophytic bacteria can regulate plant hormone levels to help their hosts counteract adverse effects imposed by abiotic and biotic stresses, but the mechanisms underlying the endophyte-induced stress resistance of plants remain largely elusive. In this study, a glucuronic acid-producing endophyte Pseudomonas sp. MCS15 alleviated cadmium (Cd) toxicity in rice plants. Inoculation with MCS15 significantly inhibited the expression of ethylene biosynthetic genes including OsACO3, OsACO4, OsACO5, OsACS2, and OsACS5 and thus reduced the content of ethylene in rice roots. In addition, the expression of iron uptake-related genes including OsIRT1, OsIRT2, OsNAS1, OsNAS2 and OsYSL15 was significantly downregulated in the MCS15-inoculated roots under Cd stress. Similarly, glucuronic acid treatment also remarkably inhibited root uptake of Cd and reduced the production of ethylene. However, treatment with 1-aminocyclopropyl carboxylic acid (ACC), a precursor of ethylene, almost abolished the MCS15 or glucuronic acid-induced inhibition of Cd accumulation in rice plants. Conversely, treatment with aminoethoxyvinyl glycine (AVG), an inhibitor of ethylene biosynthesis, markedly reduced the Cd accumulation in plants. Taken together, our results revealed that the endophytic bacteria MCS15-secreted glucuronic acid inhibited the biosynthesis of ethylene and thus weakened iron uptake-related systems in rice roots, which contributed to preventing the Cd accumulation.

6.
Anal Chim Acta ; 1180: 338862, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34538316

RESUMO

Rapid emergence of new strains of drug-resistant H1N1 influenza viruses calls for effective drugs for the controls prior to their outbreaks. In the present work, electrochemical H1N1 RNA beacons have been newly designed for exploring the potentiality of an anticancer agent of Bleomycin (BLM) with Fe (ΙΙ) ions (BLM-Fe(ΙΙ)) alternatively the treatment of drug-resistant H1N1 strains with H274Y gene mutation. Herein, biotinylated (-) ssRNA of H1N1 virus and its complementary (+) ssRNA were labeled with electrochemical signal probes of ferrocene and anthraquinone, respectively. The resultants were hybridized and conjugated with avidin-modified magnetic beads to create electrochemical RNA beacons. The electrochemical signal variation of the H1N1 RNA beacon treated with the RNA degradation agent of BLM-Fe(ΙΙ) were monitored. Results indicate that the BLM-Fe(ΙΙ) agent could effectively cleave both H1N1 dsRNAs and ssRNAs at selective cutting sites, as evidenced by the mass spectrometry analysis. This indicates that the BLM-Fe(II) agent could be utilized to block the viral-host infection process by curbing the host-cell viral RNA-mRNA transcription or inactivate the viruses through the cleavage of viral genomes. The efficiency of the BLM-Fe(ΙΙ) agent was verified with clinical seasonal H1N1 samples using real-time polymerase chain reaction. The therapeutic gene drug of BLM-Fe(ΙΙ) holds great potential for controlling new strains of H1N1 virus resistant to clinical antiviral drugs. More importantly, the so designed RNA beacons may provide a rapid, sensitive and cost-effective platform of drug screening by monitoring the drug-DNA/RNA interactions.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Preparações Farmacêuticas , Bleomicina , Farmacorresistência Viral/genética , Compostos Ferrosos , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Neuraminidase , Oseltamivir , RNA Viral/genética
7.
Anal Chim Acta ; 1147: 56-63, 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33485585

RESUMO

We report a highly sensitive approach for detecting microRNA-21 (miR-21) in cancer cells and human serum by using Au@Si nanocomposite labeled lateral flow assay. The Au@Si nanocomposite was prepared by coating numerous 3-5 nm gold nanoparticles (GNP) on a silica nanoparticle (SiNP) with a diameter of 150 nm and used as colored label on the lateral flow assay for signal amplification. TEM results show there are around 1000 GNPs coated on the SiNP surface. The principle of miR-21 detection is based on on-strip DNA-microRNA hybridization reactions to form DNA-miR-21-DNA-Au@Si complexes, which are captured on the test zone of the lateral flow test strip and produce a visible red band. A thiol-modified detecting DNA probe (Det-DNA) and a biotin-modified capturing DNA probe (Cap-DNA), which are complementary to miR-21, were used to prepare the lateral flow test strips. After systematic optimization, the method can detect a minimum concentration of 1.0 pM miR-21, which is 60 times lower than that of the GNP-based lateral flow assay (Gao et al. Biosens & Bioelectro, 2014, 54, 578-584). The method was applied to detect miR-21 in cancer cells and spiked human serum with satisfactory results.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , MicroRNAs , Nanocompostos , Neoplasias , Ouro , Humanos , Limite de Detecção , Neoplasias/diagnóstico , Neoplasias/genética
8.
Int J Mol Med ; 45(2): 543-555, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31894315

RESUMO

Non­alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide. Increasing evidence has shown that microRNAs (miRNAs) play a vital role in the progression of NAFLD. The aim of the present study was to examine the expression level and roles of miR­146a in fatty liver of high­fat diet (HFD) and ob/ob mice and fatty acid­treated hepatic cells using RT­qPCR and western blot analysis. The results showed that the expression of miR­146a was significantly decreased in the livers of high­fat diet (HFD) and ob/ob mice and free fatty acid­stimulated cells by RT­qPCR. Overexpression of hepatic miR­146a improved glucose and insulin tolerance as well as lipid accumulation in the liver by promoting the oxidative metabolism of fatty acids. In addition, the overexpression of miR­146a increased the amount of mitochondria and promoted mitochondrial respiration in hepatocytes. Similarly, inhibition of miR­146a expression levels significantly reduced mitochondrial numbers in AML12 cells as well as the expression of mitochondrial respiration related genes. Additionally, MED1 was a direct target of miR­146a and restoring MED1 abolished the metabolic effects of miR­146a on lipid metabolism and mitochondrial function. Therefore, results of the present study identified a novel function of miR­146a in glucose and lipid metabolism in targeting MED1, suggesting that miR­146a serves as a potential therapeutic target for metabolic syndrome disease.


Assuntos
Glucose/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Subunidade 1 do Complexo Mediador/genética , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Regulação para Baixo , Fígado/patologia , Masculino , Subunidade 1 do Complexo Mediador/metabolismo , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Regulação para Cima
9.
Environ Toxicol ; 35(3): 313-321, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31670868

RESUMO

Although the roles of long non-coding RNA (lncRNA) ANRIL (Antisense non-coding RNA in the INK4A locus) have been established in various tumors, its roles in mitochondrial metabolic reprogramming of hepatocellular carcinoma (HCC) cells are still unclear. This work aims to explore lncRNA ANRIL roles in regulating the mitochondrial metabolic reprogramming of liver cancer cells. First, we found that lncRAN ANRIL expression was significantly increased in HCC tissues or cells compared with the normal adjacent tissues and normal tissues or cells. Functional experiment showed that overexpression of lncRNA ANRIL promoted mitochondrial function in HCC cells, evident by the increased mitochondrial DNA copy numbers, ATP (Adenosine triphosphate) level, mitochondrial membrane potential, and the expression levels of mitochondrial markers, while ANRIL knockdown exerted the opposite effects. Mechanistically, lncRNA ANRIL acted as a competing endogenous RNA to increase ARL2 (ADP-ribosylationfactor-like 2) expression via sponging miR-199a-5p. Notably, the miR-199a-5p/ARL2 axis is necessary for ANRIL-mediated promoting effects on HCC cell mitochondrial function. This work reveals a novel ANRIL-miR-199a-5p-ARL2 axis in HCC cell progression, which might provide potential targets for HCC treatment.


Assuntos
Carcinoma Hepatocelular/genética , Proteínas de Ligação ao GTP/metabolismo , Neoplasias Hepáticas/genética , MicroRNAs/metabolismo , Mitocôndrias/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Carcinoma Hepatocelular/metabolismo , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Potencial da Membrana Mitocondrial , Camundongos , RNA Longo não Codificante/fisiologia
10.
Transl Res ; 213: 67-89, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31442419

RESUMO

Pancreatic cancer is characterized by extremely high mortality and poor prognosis and is projected to be the leading cause of cancer deaths by 2030. Due to the lack of early symptoms and appropriate methods to detect pancreatic carcinoma at an early stage as well as its aggressive progression, the disease is often quite advanced by the time a definite diagnosis is established. The 5-year relative survival rate for all stages is approximately 8%. Therefore, detection of pancreatic cancer at an early surgically resectable stage is the key to decrease mortality and to improve survival. The traditional methods for diagnosing pancreatic cancer involve an imaging test, such as ultrasound or magnetic resonance imaging, paired with a biopsy of the mass in question. These methods are often expensive, time consuming, and require trained professionals to use the instruments and analyze the imaging. To overcome these issues, biosensors have been proposed as a promising tool for the early diagnosis of pancreatic cancer. The present review critically discusses the latest developments in biosensors for the early diagnosis of pancreatic cancer. Protein and microRNA biomarkers of pancreatic cancer and corresponding biosensors for pancreatic cancer diagnosis have been reviewed, and all these cases demonstrate that the emerging biosensors are becoming an increasingly relevant alternative to traditional techniques. In addition, we discuss the existing problems in biosensors and future challenges.


Assuntos
Técnicas Biossensoriais/métodos , Neoplasias Pancreáticas/diagnóstico , Biomarcadores Tumorais/metabolismo , Detecção Precoce de Câncer , Técnicas Eletroquímicas , Humanos , Óptica e Fotônica
11.
J Food Sci Technol ; 51(1): 51-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24426047

RESUMO

Instantaneous controlled pressure drop (DIC) was applied to obtain a suitable cell disruption extent as a technology in green tea processing. Microstructural observations showed that DIC increased cell disruption in an even manner as reflected from loosened palisade, distorted cells, widened space between cells, disrupted and rearranged cellular membrane in tea leaves. Color difference determination supported that DIC could facilitate the release and transport of cell contents. DIC sample showed a rise in redness, over 2.5 times greater than the control after spreading naturally for 24 h. Chemical determination revealed a better infusion behavior of tea polyphenols and amino acids in green tea manufactured by DIC method both at high and low temperature. The increase in tea polyphenols content in liquor for the first brew from twisted and needle tea was about 35% and that from flat tea was about 15% in DIC method over the traditional processing. These results suggest that DIC process can be applied in green tea processing for both a traditional product and a new kind of tea capable of making with cold water.

12.
BMC Microbiol ; 13: 31, 2013 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-23391153

RESUMO

BACKGROUND: Shigella is a major pathogen responsible for bacillary dysentery, a severe form of shigellosis. Severity of the disease depends on the virulence of the infecting strain. Shigella pathogenicity is a multi-gene phenomenon, involving the participation of genes on an unstable large virulence plasmid and chromosomal pathogenicity islands. RESULTS: A multiplex PCR (mPCR) assay was developed to detect S. flexneri 2a from rural regions of Zhengding (Hebei Province, China). We isolated and tested 86 strains using our mPCR assay, which targeted the ipaH, ial and set1B genes. A clinical strain of S. flexneri 2a 51 (SF51) containing ipaH and ial, but lacking set1B was found. The virulence of this strain was found to be markedly decreased. Further testing showed that the SF51 strain lacked pic. To investigate the role of pic in S. flexneri 2a infections, a pic knockout mutant (SF301-∆ pic) and two complementation strains, SF301-∆ pic/pPic and SF51/pPic, were created. Differences in virulence for SF51, SF301-∆ pic, SF301-∆ pic/pPic, SF51/pPic and S. flexneri 2a 301 (SF301) were compared. Compared with SF301, both SF51 and SF301-∆ pic exhibited lower levels of Hela cell invasion and resulted in reduced keratoconjunctivitis, with low levels of tissue damage seen in murine eye sections. The virulence of SF301-∆ pic and SF51 was partially recovered in vitro and in vivo through the addition of a complementary pic gene. CONCLUSIONS: The pic gene appears to be involved in an increase in pathogenicity of S. flexneri 2a. This gene assists with bacterial invasion into host cells and alters inflammatory reactions.


Assuntos
Proteínas de Bactérias/metabolismo , Disenteria Bacilar/patologia , Deleção de Genes , Serina Proteases/metabolismo , Shigella flexneri/patogenicidade , Fatores de Virulência/metabolismo , Animais , Proteínas de Bactérias/genética , China , Modelos Animais de Doenças , Disenteria Bacilar/microbiologia , Endocitose , Células Epiteliais/microbiologia , Olho/patologia , Feminino , Teste de Complementação Genética , Células HeLa , Histocitoquímica , Humanos , Ceratoconjuntivite/microbiologia , Ceratoconjuntivite/patologia , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase , População Rural , Serina Proteases/genética , Shigella flexneri/genética , Shigella flexneri/isolamento & purificação , Virulência , Fatores de Virulência/genética
13.
Int J Mol Sci ; 12(11): 7708-19, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22174626

RESUMO

Seeds are another product in addition to leaves (raw materials for teas) of tea (Camellia sinensis L.) plant. The great increase of tea consumption in recent years raises the challenge of finding commercial applications for tea seeds. In the present study, supercritical carbon dioxide (SC-CO(2)) extraction edible oil from tea seed was carried out, response surface methodology (RSM) was used to optimize processing parameters including time (20-90 min), temperature (35-45 °C) and pressure (50-90 MPa). The fatty acid composition and antioxidant activity of the extracted oil was also investigated. The highest yield of oil (29.2 ± 0.6%) was obtained under optimal SC-CO(2) extraction conditions (45 °C, 89.7 min and 32 MPa, respectively), which was significantly higher (p < 0.05) than that (25.3 ± 1.0%) given by Soxhlet extraction. Meanwhile, tea seed oil extracted by SC-CO(2) contained approximately 80% unsaturated fatty acids and showed a much stronger scavenging ability on the DPPH radical than that extracted by Soxhlet. SC-CO(2) is a promising alternative for efficient extraction of edible oil from tea seed. Moreover, tea seed oil extracted by SC-CO(2) is highly edible and has good antioxidant activity, and therefore may play a potential role as a health-promoting food resource in human diets.


Assuntos
Antioxidantes/análise , Camellia sinensis/química , Ácidos Graxos Insaturados/análise , Óleos de Plantas/química , Sementes/química , Antioxidantes/química , Dióxido de Carbono , Ácidos Graxos Insaturados/química , Extratos Vegetais/análise , Extratos Vegetais/química , Pressão , Solventes/química , Chá/química , Temperatura
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