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1.
Mikrochim Acta ; 191(5): 283, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652169

RESUMO

A new method is proposed for detecting typical melamine dopants in food using surface-enhanced Raman scattering (SERS) biosensing technology. Melamine specific aptamer was used as the identification probe, and gold magnets (AuNPs@MNPs) and small gold nanoparticles (AuNPs@MBA) were used as the basis for Raman detection. The Raman signal of the detection system can directly detect melamine quantitatively. Under optimized conditions, the detection of melamine was carried out in the low concentration range of 0.001-500 mg/kg, the enhancement factor (EF) was 2.3 × 107, and the detection limit was 0.001 mg/kg. The method is sensitive and rapid, and can be used for the rapid detection of melamine in the field environment.


Assuntos
Aptâmeros de Nucleotídeos , Ouro , Limite de Detecção , Nanopartículas Metálicas , Análise Espectral Raman , Triazinas , Triazinas/análise , Triazinas/química , Análise Espectral Raman/métodos , Ouro/química , Nanopartículas Metálicas/química , Aptâmeros de Nucleotídeos/química , Contaminação de Alimentos/análise , Técnicas Biossensoriais/métodos , DNA/química
2.
Insects ; 15(3)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38535389

RESUMO

Potatoes hold the distinction of being the largest non-cereal food crop globally. The application of insecticides has been the most common technology for pest control. The repeated use of synthetic insecticides of the same chemical class and frequent applications have resulted in the emergence of insecticide resistance. Two closely related pests that feed on potato crops are the potato tuber moth, Phthorimaea operculella, and the tomato leafminer, Phthorimaea absoluta (syn. Tuta absoluta). Previous studies indicated the existence of insecticide resistance to various classes of insecticides including organophosphates, carbamates, and pyrethroids in field populations of P. operculella and P. absoluta. However, the exact mechanisms of insecticide resistance in P. operculella and to a lesser extent P. absoluta remain still poorly understood. Detecting resistance genotypes is crucial for the prediction and management of insecticide resistance. In this study, we identified multiple genetic mutations related to insecticide resistance in two species of Phthorimaea. An unexpected genetic divergence on target-site mutations was observed between P. operculella and P. absoluta. Three mutations (A201S, L231V, and F290V) in Ace1 (acetylcholinesterase), four mutations (M918T, L925M, T928I, and L1014F) in VGSC (voltage-gated sodium channel), and one mutation (A301S) in RDL (GABA-gated chloride channel) have been detected with varying frequencies in Chinese P. absoluta field populations. In contrast, P. operculella field populations showed three mutations (F158Y, A201S, and L231V) in Ace1, one mutation (L1014F) in VGSC at a lower frequency, and no mutation in RDL. These findings suggest that pyrethroids, organophosphates, and carbamates are likely to be ineffective in controlling P. absoluta, but not P. operculella. These findings contributed to a deeper understanding of the presence of target-site mutations conferring resistance to commonly used (and cheap) classes of insecticides in two closely related potato pests. It is recommended to consider the resistance status of both pests for the implementation of resistance management strategies in potatoes.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38408379

RESUMO

Mitofusin 2 (MFN2) has been found to be downregulated in patients with Alzheimer disease (AD) but little is known about its roles in the pathogenesis of AD. We explored the mechanism of N6-methyladenosine (m6A) methylation of Mfn2 in hippocampal mitochondrial dysfunction in an AD mouse model. APP/PS1 transgenic mice underwent stereotaxic injection of adeno-associated viruses and their behaviors were assessed. METTL3 and MFN2 expressions were measured by qRT-PCR and Western blot, accompanied by assessment of mitochondrial morphology, ATP, mitochondrial membrane potential, and amyloid-ß content. Binding between METTL3 and MFN2, the total amount of m6A, and the m6A modification of Mfn2 were also determined. METTL3 and MFN2 were downregulated in hippocampal tissues of the AD model mice; METTL3 enhanced MFN2 expression via m6A modification. Overexpression of METTL3 or MFN2 ameliorated mitochondrial dysfunction indicated by fewer damaged mitochondria, increased ATP and JC-1 levels, and reduced Aß content; improved cognitive impairment in the mice was indicated by the novel object discrimination index and Morris water maze tests. Effects of METTL3 overexpression were abrogated by further knockdown of MFN2. Thus, METTL3 ameliorated mitochondrial dysfunction and cognitive impairment in the AD model mice by increasing MFN2 expression via m6A modification.

4.
ACS Appl Mater Interfaces ; 16(8): 10522-10531, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38353225

RESUMO

A facilely in situ fabricated hydrogen-bonded organic framework (HOF) hydrogel film with perfect photoluminescent performance was designed for visual sensing of tetracycline antibiotics (TCs) and information security. Luminescent HOF (MA-IPA) was combined with sodium alginate (SA) through hydrogen bonding actions and electrostatic interactions, then cross-linked with Ca2+ ions to form HOF hydrogel film (Ca@MA-IPA@SA). The HOF hydrogel film exhibited exceptional mechanical robustness along with stable blue fluorescence and ultralong green phosphorescence. After exposure to TCs, Ca2+ was combined with TCs to generate a new green fluorescence exciplex (TC-Ca2+) in hydrogel films. Due to fluorescence resonance energy transfer, the fluorescence of MA-IPA was quenched, and the fluorescent color of the HOF hydrogel film was changed from blue to green. This dichromatic fluorescent response is convenient for the visual and rapid detection of TCs. The detection limits of tetracycline (TC), oxytetracycline (OTC), and chlortetracycline (CTC) were 5.1, 7.7, and 32.7 ng mL-1, respectively. Importantly, this hydrogel sensing platform was free of tedious operation and enabled the ultrasensitive and selective detection of TCs within 6 min. It has been successfully applied to TC detection in pork and milk samples. Based on the stable photoluminescence performance of HOF hydrogel films and fluorescent-responsive properties to TCs, two types of anticounterfeiting arrays were fabricated for information encryption and decryption. This work provides a novel approach for on-site detection of TCs and offers valuable insights into information security.


Assuntos
Antibacterianos , Metilgalactosídeos , Tetraciclinas , Ligação de Hidrogênio , Tetraciclina , Hidrogéis
5.
Anal Chim Acta ; 1292: 342245, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38309853

RESUMO

BACKGROUND: DNA tweezers, classified as DNA nanomachines, have gained prominence as multifunctional biosensors due to their advantages, including a straightforward structure, response mechanism, and high programmability. While the DNA tweezers demonstrate simultaneous, rapid, and stable responses to different targets, their detection sensitivity requires enhancement. Some small molecules, such as mycotoxins, often require more sensitive detection due to their extremely high toxicity. Therefore, more effective signal amplification strategies are needed to further enhance the sensitivity of DNA tweezers in biosensing. RESULTS: We designed programmable DNA tweezers that detect small-molecule mycotoxins and miRNAs through simple sequence substitution. While the DNA tweezers demonstrate simultaneous, rapid, and stable responses to different targets, their detection sensitivity requires enhancement. We introduced the Strand Displacement Amplification (SDA) technique to address this limitation, proposing a strategy of novel programmable DNA tweezers-SDA ultrasensitive signal amplification fluorescence sensing. We specifically investigate the effectiveness of this approach concerning signal amplification for two critical mycotoxins: aflatoxin B1 (AFB1) and zearalenone (ZEN). Results indicate that the detection ranges of AFB1 and ZEN via this strategy were 1-10,000 pg mL -1 and 10-100,000 pg mL -1, respectively, with corresponding detection limits of 0.933 pg mL -1 and 1.07 pg mL -1. Compared with the DNA tweezers direct detection method for mycotoxins, the newly constructed programmable DNA tweezers-SDA fluorescence sensing strategy achieved a remarkable 104-fold increase in the detection sensitivity for AFB1 and ZEN. SIGNIFICANCE: The constructed programmable DNA tweezers-SDA ultrasensitive signal-amplified fluorescence sensing strategy exhibits excellent detection performance for mycotoxins. The superb versatility of this strategy allows the developed method to be easily used for detecting other analytes by simply replacing the aptamer and cDNA, which has incredible potential in various fields such as food safety screening, clinical diagnostics, and environmental analysis.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Micotoxinas , Zearalenona , Micotoxinas/análise , Zearalenona/análise , DNA , DNA Complementar , Limite de Detecção , Aflatoxina B1/análise
6.
Small ; : e2308247, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38174612

RESUMO

Iron oxide nanoparticles are a kind of important biomedical nanomaterials. Although their industrial-scale production can be realized by the conventional coprecipitation method, the controllability of their size and morphology remains a huge challenge. In this study, a kind of synthetic polypeptide Mms6-28 which mimics the magnetosome protein Mms6 is used for the bioinspired synthesis of Fe3 O4 nanoparticles (NPs). Magnetosomes-like Fe3 O4 NPs with uniform size, cubooctahedral shape, and smooth crystal surfaces are synthesized via a partial oxidation process. The Mms6-28 polypeptides play an important role by binding with iron ions and forming nucleation templates and are also preferably attached to the [100] and [111] crystal planes to induce the formation of uniform cubooctahedral Fe3 O4 NPs. The continuous release and oxidation of Fe2+ from pre-formed Fe2+ -rich precursors within the Mms6-28-based template make the reaction much controllable. The study affords new insights into the bioinspired- and bio-synthesis mechanism of magnetosomes.

7.
Open Biol ; 14(1): 230208, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38195061

RESUMO

The physiological state of an insect can affect its olfactory system. However, the molecular mechanism underlying the effect of nutrition-dependent states on odour-guided behaviours in hoverflies remains unclear. In this study, comparative transcriptome analysis of the antenna and proboscis from Eupeodes corollae under different feeding states was conducted. Compared with the previously published antennal transcriptome, a total of 32 novel chemosensory genes were identified, including 4 ionotropic receptors, 17 gustatory receptors, 9 odorant binding proteins and 2 chemosensory proteins. Analysis of differences in gene expression between different feeding states in male and female antennae and proboscises revealed that the expression levels of chemosensory genes were impacted by feeding state. For instance, the expression levels of EcorOBP19 in female antennae, EcorOBP6 in female proboscis, and EcorOR6, EcorOR14, EcorIR5 and EcorIR84a in male antennae were significantly upregulated after feeding. On the other hand, the expression levels of EcorCSP7 in male proboscis and EcorOR40 in male antennae were significantly downregulated. These findings suggest that nutritional state plays a role in the adaptation of hoverflies' olfactory system to food availability. Overall, our study provides important insights into the plasticity and adaptation of chemosensory systems in hoverflies.


Assuntos
Proteínas de Drosophila , Transcriptoma , Feminino , Masculino , Humanos , Perfilação da Expressão Gênica
8.
Compr Rev Food Sci Food Saf ; 23(1): 1-22, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38284608

RESUMO

Food is consumed by humans, which is indispensable to human life. Therefore, considerable attention of the whole society has been paid to food safety. Over the last few years, dramatic social development has brought new challenges to food safety, making developing new and quick methods for on-site food safety testing an important necessity. As a result, DNA-fueled molecular machines, characterized by high efficiency, accuracy, and sensitivity in testing, have come into the spotlight, based on which sensors can be constructed to detect toxic and harmful substances in food products. This study reviewed recent research on several DNA-fueled molecular machines, including DNA tweezers, DNA walkers, and DNA origami, for rapidly detecting toxic and harmful substances. Based on the above studies, the sensitivity and timeliness of several DNA molecular machines were summarized and compared, and the development prospect of DNA fuel molecular machines in the field of food safety detection was prospected.


Assuntos
DNA , Nanotecnologia , Humanos , Nanotecnologia/métodos , Inocuidade dos Alimentos
9.
Int J Biol Macromol ; 246: 125613, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37392921

RESUMO

Removing noxious dyes and detecting excessive metal ions in water are both effective means to prevent damage from contaminants and ensure water safety. The emphasis problems were addressed by preparation a polyacrylamide chitosan (PAAM/CS) hydrogel. Polyacrylamide (PAAM) provides overall mechanical strength to carry loads and facilitate circulation, chitosan (CS) provides adsorption positions with high adsorption capacity. Which made that PAMM/CS hydrogel efficiently performed sorption of xylenol orange (XO). As the functional dye, XO binds to PAAM/CS and confers colorimetric properties on PAAM/CS hydrogels. XO sorbed hydrogel realized fluorescence dual-signal detection of Fe3+ and Al3+ in water. The significant swelling and adsorption potency of the hydrogel, combined with the dual-signal detection capability of XO sorbed hydrogel, make this hydrogel a versatile material for environmental applications.


Assuntos
Quitosana , Poluentes Químicos da Água , Água , Adsorção , Corantes , Hidrogéis , Metais , Cinética , Íons
10.
Biosens Bioelectron ; 237: 115445, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37421799

RESUMO

Deoxyribonucleic acid (DNA) is a carrier of genetic information. DNA hybridization is characterized by predictability, diversity, and specificity owing to the strict complementary base-pairing assembly mode, which stimulates the use of DNA to build a variety of nanomachines, including DNA tweezers, motors, walkers, and robots. DNA nanomachines have become prevalent for signal amplification and transformation in the field of biosensing, providing a new method for constructing highly sensitive sensing analysis strategies. DNA tweezers have exhibited unique advantages in biosensing applications owing to their simple structures and fast responses. The two-state conformation of DNA tweezers, the open and closed states, enable them to open and close autonomously after stimulation, thus facilitating the quick detection of corresponding signal changes of different targets. This review discusses the recent progress in the application of DNA nanotweezers in the field of biosensing, and the trends in their development for application in the field of biosensing are summarized.


Assuntos
Técnicas Biossensoriais , DNA , DNA/química , Técnicas Biossensoriais/métodos , Hibridização de Ácido Nucleico , Conformação de Ácido Nucleico
11.
Int J Biol Macromol ; 242(Pt 2): 124939, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37207749

RESUMO

Odorant binding proteins (OBPs) are essential proteins in the peripheral olfactory system, responsible for odorant recognition and transport to olfactory receptors. Phthorimaea operculella (potato tuber moth) is an important oligophagous pest on Solanaceae crops in many countries and regions. PopeOBP16 is one of the OBPs in potato tuber moth. This study examined the expression profiles of PopeOBP16. The results of qPCR indicated that PopeOBP16 was highly expressed in the antennae of adults, especially in males, suggesting that it may be involved in odor recognition in adults. The electroantennogram (EAG) was used to screen candidate compounds with the antennae of P. operculella. The relative affinities of PopeOBP16 to 27 host volatiles and two sex pheromone components with the highest relative EAG responses were examined with competitive fluorescence-based binding assays. PopeOBP16 had the strongest binding affinity with the plant volatiles: nerol, 2-phenylethanol, linalool, 1,8-cineole, benzaldehyde, ß-pinene, d-limonene, terpinolene, α-terpinene, and the sex pheromone component trans-4, cis-7, cis-10-tridecatrien-1-ol acetate. The results provide a foundation for further research into the functioning of the olfactory system and the potential development of green chemistry for control of the potato tuber moth.


Assuntos
Mariposas , Receptores Odorantes , Atrativos Sexuais , Solanum tuberosum , Animais , Masculino , Odorantes , Atrativos Sexuais/metabolismo , Receptores Odorantes/química , Mariposas/metabolismo , Solanum tuberosum/química , Proteínas de Insetos/metabolismo
12.
Anal Chim Acta ; 1267: 341351, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37257972

RESUMO

Food safety is one of the greatest public health challenges. Developing ultrasensitive detection methods for analytes at ultra-trace levels is, therefore, essential. In recent years, the bio-barcode assay (BCA) has emerged as an effective ultrasensitive detection strategy that is based on the indirect amplification of various DNA probes. This review systematically summarizes the progress of fluorescence, PCR, and colorimetry-based BCA methods for the detection of various contaminants, including pathogenic bacteria, toxins, pesticides, antibiotics, and other chemical substances in food in over 120 research papers. Current challenges, including long experimental times and strict storage conditions, and the prospects for the application of BCA in biomedicine and environmental analyses, have also been discussed herein.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Ouro/química , Inocuidade dos Alimentos , Sondas de DNA/química , Tecnologia
13.
Talanta ; 258: 124401, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36867957

RESUMO

Agricultural products are frequently contaminated by mycotoxins. Multiplex, ultrasensitive, and rapid determination of mycotoxins is still a challenging problem, which is of great significance to food safety and public health. Herein, a surface-enhanced Raman scattering (SERS) based lateral flow immunoassay (LFA) for the simultaneous on-site determination of aflatoxin B1 (AFB1) and ochratoxin A (OTA) on the same test line (T line) was developed, in this study. In practice, two kinds of Raman reporters 4-mercaptobenzoic acid (4-MBA), and 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) encoded silica-encapsulated gold nanotags (Au4-MBA@SiO2 and AuDNTB@SiO2) were used as detection markers to identify the two different mycotoxins. Through systematic optimization of the experimental conditions, this biosensor has high sensitivity and multiplexing with the limits of detection (LODs) at 0.24 pg mL-1 for AFB1 and 0.37 pg mL-1 for OTA. These are far below the regulatory limits set by the European Commission, in which the minimum LODs for AFB1 and OTA are 2.0 and 3.0 µg kg-1. In the spiked experiment, the food matrix are corn, rice, and wheat, and the mean recoveries of the two mycotoxins ranged from 91.0% ± 6.3%-104.8% ± 5.6% for AFB1 and 87.0% ± 4.2%-112.0% ± 3.3% for OTA. These results demonstrate that the developed immunoassay has good stability, selectivity, and reliability, which can be used for routine monitoring of mycotoxin contamination.


Assuntos
Nanopartículas Metálicas , Micotoxinas , Aflatoxina B1/análise , Dióxido de Silício , Reprodutibilidade dos Testes , Micotoxinas/análise , Imunoensaio , Ouro , Limite de Detecção
14.
Food Funct ; 14(4): 2212-2222, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36757176

RESUMO

Inflammatory bowel disease (IBD) is a global health problem in which metabolite alteration plays an important pathogenic role. Bovine milk-derived extracellular vesicles (mEVs) have been shown to regulate nutrient metabolism in healthy animal models. This study investigated the effect of oral mEVs on metabolite changes in DSS-induced murine colitis. We performed metabolomic profiling on plasma samples and measured the concentrations of lipids and amino acids in both fecal samples and colonic tissues. Plasma metabolome analysis found that mEVs significantly upregulated 148 metabolite levels and downregulated 44 metabolite concentrations (VIP > 1, and p < 0.05). In the fecal samples, mEVs significantly increased the contents of acetate and butyrate and decreased the levels of tridecanoic acid (C13:0), methyl cis-10-pentadecenoate (C15:1) and cis-11-eicosenoic acid (C20:1). Moreover, the concentrations of eicosadienoic acid (C20:2), eicosapentaenoic acid (C20:5), and docosahexaenoic acid (C22:6) were decreased in colonic tissues with mEV supplementation. In addition, compared with the DSS group, mEVs significantly increased the content of L-arginine, decreased the level of L-valine in the fecal samples, and also decreased the levels of L-serine and L-glutamate in the colonic tissues. Collectively, our findings demonstrated that mEVs could recover the metabolic abnormalities caused by inflammation and provided novel insights into mEVs as a potential modulator for metabolites to prevent and treat IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Camundongos , Animais , Leite/metabolismo , Inflamação , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Aminoácidos , Lipídeos , Modelos Animais de Doenças , Sulfato de Dextrana/efeitos adversos , Camundongos Endogâmicos C57BL
15.
Talanta ; 255: 124249, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36610257

RESUMO

It is extremely necessary to establish a rapid and high-throughput method to detect mycotoxins in food, because grains and cereals are greatly vulnerable to mycotoxins before and after harvest. In this study, we developed a portable aptasensor based on streptavidin magnetic microspheres (MMPs) and hybridization chain reaction (HCR) to simultaneously detect T-2 toxin and zearalenone (ZEN) in corn and oat flour. The MMPs compete with the aptamer for binding, which releases more H0 and triggers HCR with the H1 intermediate modified using 6-FAM and BHQ-1 and the unmodified H2. Subsequently, placing the HCR system corresponding to T-2 and ZEN in a constant-temperature fluorescence detector resulted in well-recovered fluorescence of the HCR products. T-2 and ZEN exhibited good fluorescence response in the dynamic range of 0.001-10 ng mL-1 and 0.01-100 ng mL-1 with detection limits of 0.1 pg mL-1 and 1.2 pg mL-1, respectively. In addition, this strategy achieved the selective detection of T-2 and ZEN in the spiked corn and oat flour samples. The results are also in good agreement with those obtained using commercial ELISA kits. This developed aptasensor with the characteristics of simple operation and portability has the application potential of establishing sensitive and portable field detection of various mycotoxins.


Assuntos
Aptâmeros de Nucleotídeos , Micotoxinas , Toxina T-2 , Zearalenona , Zearalenona/análise , Toxina T-2/análise , Contaminação de Alimentos/análise , Micotoxinas/análise , Aptâmeros de Nucleotídeos/genética , Zea mays/metabolismo , Limite de Detecção
16.
Anal Chim Acta ; 1228: 340312, 2022 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-36127008

RESUMO

The illegal addition of melamine (MEL) into pet foods and infant milk powder has caused great concern among people. In this study, a point-of-care testing (POCT) method was developed by combining stimuli-responsive deoxyribonucleic acid (DNA) hydrogels with microfluidic chips to achieve portable and sensitive detection of MEL. With the MEL aptamer (MA) acting as a cross-linker, DNA hydrogel-coated gold nanoparticles (AuNPs) served as a basis for colorimetric detection and quantitative analysis. In the presence of MEL, it competitively binds to the aptamer, causing disintegration of the DNA hydrogels and a release of the coated AuNPs, making it possible to visually detect and quantitatively measure the MEL. Under optimal conditions, the detection range of MEL using DNA hydrogels was 0.1-100 µM and the limit of detection (LOD) was 42 nM. This portable, sensitive, and user-friendly field test equipment was developed to avoid the use of non-portable laboratory instruments. Furthermore, we combined microfluidic chips with the properties of DNA hydrogels, making it possible to quantitatively detect MEL by taking photos and analyzing the gray value using software in accordance with the different colors of copolymerization solutions after the reaction. The detection range of MEL using the microfluidic chip-based method was 0.2-50 µM, and the LOD was 37 nM. Neither trained operators nor large-scale instruments are needed for using this method to conduct portable and sensitive field detection of the targets, which highlights the methods excellent potential in food security, clinical tests, environmental monitoring, and other aspects.


Assuntos
Ouro , Nanopartículas Metálicas , DNA , Humanos , Hidrogéis , Microfluídica , Pós , Triazinas
17.
Mater Today Bio ; 16: 100430, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36157049

RESUMO

Deoxyribonucleic acid (DNA) hydrogels combine the properties of DNAs and hydrogels, and adding functionalized DNAs is key to the wide application of DNA hydrogels. In stimuli-responsive DNA hydrogels, the DNA transcends its application in genetics and bridges the gap between different fields. Specifically, the DNA acts as both an information carrier and a bridge in constructing DNA hydrogels. The programmability and biocompatibility of DNA hydrogel make it change macroscopically in response to a variety of stimuli. In order to meet the needs of different scenarios, DNA hydrogels were also designed into microcapsules, beads, membranes, microneedle patches, and other forms. In this study, the stimuli were classified into single biological and non-biological stimuli and composite stimuli. Stimuli-responsive DNA hydrogels from the past five years were summarized, including but not limited to their design and application, in particular logic gate pathways and signal amplification mechanisms. Stimuli-responsive DNA hydrogels have been applied to fields such as sensing, nanorobots, information carriers, controlled drug release, and disease treatment. Different potential applications and the developmental pro-spects of stimuli-responsive DNA hydrogels were discussed.

18.
Int J Mol Sci ; 23(14)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35887147

RESUMO

Hypocalcemia is caused by a sharp decline in blood calcium concentration after dairy cow calving, which can lead to various diseases or even death. It is necessary to develop an inexpensive, easy-to-operate, reliable sensor to diagnose hypocalcemia. The cellulose-paper-based microfluidic field-effect biosensor is promising for point-of-care, but it has poor mechanical strength and a short service life after exposure to an aqueous solution. Octadecyltrichlorosilane (OTS), as a popular organosilane derivative, can improve the hydrophobicity of cellulose paper to overcome the shortage of cellulose paper. In this work, OTS was used to produce the superhydrophobic cellulose paper that enhances the mechanical strength and short service life of MFB, and a microfluidic field-effect biosensor (MFB) with semiconducting single-walled carbon nanotubes (SWNTs) and DNAzyme was then developed for the Ca2+ determination. Pyrene carboxylic acid (PCA) attached to SWNTs through a non-covalent π-π stacking interaction provided a carboxyl group that can bond with an amino group of DNAzyme. Two DNAzymes with different sensitivities were designed by changing the sequence length and cleavage site, which were functionalized with SPFET/SWNTs-PCA to form Dual-MFB, decreasing the interference of impurities in cow blood. After optimizing the detecting parameters, Dual-MFB could determine the Ca2+ concentration in the range of 25 µM to 5 mM, with a detection limit of 10.7 µM. The proposed Dual-MFB was applied to measure Ca2+ concentration in cow blood, which provided a new method to diagnose hypocalcemia after dairy cow calving.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Hipocalcemia , Nanotubos de Carbono , Técnicas Biossensoriais/métodos , Ácidos Carboxílicos/química , Celulose , Humanos , Interações Hidrofóbicas e Hidrofílicas , Hipocalcemia/diagnóstico , Microfluídica , Nanotubos de Carbono/química
19.
Nutrients ; 14(15)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35893911

RESUMO

Evidence shows that effective nutritional intervention can prevent or mitigate the risk and morbidity of inflammatory bowel disease (IBD). Bovine milk extracellular vesicles (mEVs), a major bioactive constituent of milk, play an important role in maintaining intestinal health. The aims of this study were to assess the effects of mEV pre-supplementation on the colonic transcriptome and proteome in dextran sulphate sodium (DSS)-induced acute colitis, in order to understand the underlying molecular mechanisms of mEV protection against acute colitis. Our results revealed that dietary mEV supplementation alleviated the severity of acute colitis, as evidenced by the reduced disease activity index scores, histological damage, and infiltration of inflammatory cells. In addition, transcriptome profiling analysis found that oral mEVs significantly reduced the expression of pro-inflammatory cytokines (IL-1ß, IL-6, IL-17A and IL-33), chemokine ligands (CXCL1, CXCL2, CXCL3, CXCL5, CCL3 and CCL11) and chemokine receptors (CXCR2 and CCR3). Moreover, oral mEVs up-regulated 109 proteins and down-regulated 150 proteins in the DSS-induced murine model, which were involved in modulating amino acid metabolism and lipid metabolism. Collectively, this study might provide new insights for identifying potential targets for the therapeutic effects of mEVs on colitis.


Assuntos
Colite , Vesículas Extracelulares , Animais , Colite/metabolismo , Colo/metabolismo , Citocinas/metabolismo , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Vesículas Extracelulares/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Leite/metabolismo , Proteoma , Transcriptoma
20.
Transl Pediatr ; 11(6): 947-953, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35800270

RESUMO

Background: The relationship between abnormal electroencephalogram (EEG) and epilepsy recurrence after antiepileptic drug (AED) withdrawal has been controversial. We aimed to explore the relationship between abnormal EEG after AED withdrawal and the risk of epilepsy recurrence in children. Methods: Literature retrieval was performed using the PubMed, EMBASE, Medline, CENTRAL, and China National Knowledge Infrastructure (CNKI) databases. Included literatures were subjects of pediatric epilepsy patients who discontinued medication. The recurrence rate of epilepsy in patients with normal and abnormal EEG after AED withdrawal was observed. The Newcastle-Ottawa scale (NOS) was used to evaluate the quality of literatures. The Chi-square test was used to test heterogeneity. If heterogeneity between the articles existed, a random-effects model was used; otherwise, fixed-effects models were used. Subgroup analysis was used to explore the causes of heterogeneity. The odds ratio (OR) and 95% confidence interval (CI) were calculated using the Mantel-Haenszel statistical method. OR was not adjusted for other factors. Results: A total of 843 articles were retrieved. Nine studies were included, with a total of 1,663 patients, including 1,299 patients with normal EEG and 364 patients with abnormal EEG. Compared with the normal EEG patients, the OR of recurrence rate after AEDs withdrawal was 3.02 (P=0.0003), with heterogeneity (P<0.0001). The funnel plot indicated that there was no publication bias among the studies. The not partial seizure group analysis showed OR =1.70 (P=0.003) and no heterogeneity (P=0.70) in patients with abnormal EEG compared to those with normal EEG. In the partial seizures subgroup, the OR of the recurrence rate after AED withdrawal was 8.08 (P<0.00001) compared with the normal EEG patients, and there was no heterogeneity (P=0.29). The funnel chart shows that the partial seizures type subgroup analysis revealed positive results, while the not partial seizure group analysis reported negative results, indicating publication bias. Conclusions: The risk of epilepsy recurrence is higher in children with abnormal EEG after AED withdrawal, regardless of seizure type. For pediatric epilepsy patients with abnormal EEG after AED withdrawal, a more cautious discontinuation regimen, closer follow-up and monitoring are required.

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