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1.
Georgian Med News ; (334): 83-85, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36864798

RESUMO

Chronic alcohol use, smoking, poor dental hygiene, absorbed sun radiation over the years, fair skin (Fitzpatrick type 1), light eyes, painful sunburns, congenital or acquired immunosuppression, certain rare syndromes, as well as infections with human papillomaviruses are perceived as risk factors for the development of squamous cell carcinoma of the lips. The new and at the same time modern aspects involving the pathogenesis of keratinocyte tumors in practice prove to be quite problematic for both patients and clinicians. These aspects are involved in the contamination or increased availability of certain nitrosamines in the antihypertensive medications. A serious international study in the last year has linked the intake of potentially contaminated (established availability without data on whether it exceeds the so-called ADI/acceptable daily intake dose) with nitrosamines valsartan with a relatively low, but still present risk of melanoma development. On the other hand, data from 2017 associate individual monotherapy of arterial hypertension with sartans with a significantly increased/statistically significant risk of squamous cell carcinomas development: more than a two-fold increased risk. It should be noted that at that time the problems with nitrosamines were completely unknown to the medical community. At the moment, there are numerous case studies that connect the use of sartans with the development of keratinocyte tumors - either single or multiple. We describe the first case of a patient who took eprosartan at a dose of 600 mg once a day for a total period of about 15 years with intake interruptions of no more than 6 years. Primary complaints in the lower lip area are from about 6 months. The preoperative biopsy showed evidence of squamous cell carcinoma. A multidisciplinary team performed a successful surgical treatment using the Karapandzic method, achieving an optimal aesthetic result. Based on the available literature data, the possible role of nitrosamines as a potential trigger for the development of squamous cell carcinoma is discussed.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II , Carcinoma de Células Escamosas , Humanos , Carcinoma de Células Escamosas/induzido quimicamente , Acrilatos , Imidazóis
2.
Int J Mol Sci ; 24(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36835361

RESUMO

Here we aimed to establish a simple detection method for detecting circulating tumor cells (CTCs) in the blood sample of colorectal cancer (CRC) patients using poly(2-methoxyethyl acrylate) (PMEA)-coated plates. Adhesion test and spike test using CRC cell lines assured efficacy of PMEA coating. A total of 41 patients with pathological stage II-IV CRC were enrolled between January 2018 and September 2022. Blood samples were concentrated by centrifugation by the OncoQuick tube, and then incubated overnight on PMEA-coated chamber slides. The next day, cell culture and immunocytochemistry with anti-EpCAM antibody were performed. Adhesion tests revealed good attachment of CRCs to PMEA-coated plates. Spike tests indicated that ~75% of CRCs from a 10-mL blood sample were recovered on the slides. By cytological examination, CTCs were identified in 18/41 CRC cases (43.9%). In cell cultures, spheroid-like structures or tumor-cell clusters were found in 18/33 tested cases (54.5%). Overall, CTCs and/or growing circulating tumor cells were found in 23/41 CRC cases (56.0%). History of chemotherapy or radiation was significantly negatively correlated with CTC detection (p = 0.02). In summary, we successfully captured CTCs from CRC patients using the unique biomaterial PMEA. Cultured tumor cells will provide important and timely information regarding the molecular basis of CTCs.


Assuntos
Neoplasias Colorretais , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patologia , Polímeros/química , Acrilatos/química , Neoplasias Colorretais/patologia
3.
Biomacromolecules ; 24(3): 1184-1193, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36808988

RESUMO

Polyurethane materials will come into contact with different solvents in daily life, and at the same time, they will be subject to different degrees of collision, wear and tear. Failure to take corresponding preventative or reparative measures will result in a waste of resources and an increase in costs. To this end, we prepared a novel polysiloxane with isobornyl acrylate and thiol groups as side groups, which was further used in the preparation of poly(thiourethane-urethane) materials. Thiourethane bonds generated by the click reaction of thiol groups with isocyanates endow poly(thiourethane-urethane) materials with the ability to heal and reprocess. Isobornyl acrylate with a large sterically hindered rigid ring promotes segment migration, accelerating the exchange of thiourethane bonds, which is beneficial to the recycling of materials. These results not only promote the development of terpene derivative-based polysiloxanes but also show the great potential of thiourethane as a dynamic covalent bond in the field of polymer reprocessing and healing.


Assuntos
Acrilatos , Siloxanas , Poliuretanos/química , Compostos de Sulfidrila
4.
Biomacromolecules ; 24(3): 1287-1298, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36745900

RESUMO

Ion conductive hydrogels (ICHs) have attracted great interest in the application of ionic skin because of their superior characteristics. However, it remains a challenge for ICHs to achieve balanced properties of high strength, large fracture strain, self-healing and freezing tolerance. In this study, a strong, stretchable, self-healing and antifreezing ICH was demonstrated by rationally designing a multiphysically cross-linked network structure consisting of the hydrophobic association, metal-ion coordination and chain entanglement among poly(acrylic acid) (PAA) polymer chains. The deliberately designed Brij S 100 acrylate (Brij-100A) micelle cross-linker can effectively dissipate energy and endow hydrogels with desirable stretchability. The self-healing ability of hydrogels originates from the reversible hydrophobic association in micelles and Fe3+-COO- coordination. After the addition of NaCl, the chain-entangled physical network caused by the salting-out effect can both enhance mechanical strength and promote electron transport. With the synergy of hydrophobic association, mental-ligand coordination and chain entanglement, the PAA/Brij-100A/Fe3+/NaCl (PAA/BA/Fe3+/NaCl) hydrogels exhibited a high tensile strain of 1140%, a tensile strength of 0.93 MPa and a toughness of 3.48 MJ m-3. Besides, the PAA/BA/Fe3+/NaCl hydrogels exhibited a high conductivity of 0.43 S m-1 and good freezing resistance. The ionic skin based on the PAA/BA/Fe3+/NaCl hydrogels showed high sensitivity (GF = 5.29), wide strain range (0-950%), fast response time (220 ms) and good stability. Also, the self-healing ability of the ionic skin can significantly prolong its service time, and the antifreezing property can broaden its applicable temperature. This study offers new insight into the design of multifunctional ionic skin for wearable electronics.


Assuntos
Hidrogéis , Cloreto de Sódio , Pele , Acrilatos , Condutividade Elétrica , Íons , Micelas
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 293: 122447, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36764167

RESUMO

A colorimetric probe TQA ((E)-4-(((8-(sec-butoxy)-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-9-yl)methylene)amino)benzylacrylate) possessing greater potent towards the sensing of cysteine was successfully synthesized and characterized. The aqueous soluble probe TQA detects Cys based on "ON-OFF" effect with excellent absorbance and emission properties. The probe TQA detects Cys up to its ultra-low level concentration of 1.5 nM and also quantifies the Cys up to 5.05 nM with the quicker response time of 140 s (2.3 min). In addition, the color change produced by the probe TQA on integrated with Cys was also identified easily via paper strip, cotton wool buds and RGB color picker app in smart mobiles. Further, the admirable selectivity and sensitivity of the probe TQA towards Cys extends its utility towards food samples and imaging of live HeLa cells.


Assuntos
Cisteína , Água , Humanos , Células HeLa , Acrilatos , Corantes Fluorescentes
6.
Open Biol ; 13(3): 220324, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36854378

RESUMO

Cytokinesis is a fundamental process for bacterial survival and proliferation, involving the formation of a ring by filaments of the GTPase FtsZ, spatio-temporally regulated through the coordinated action of several factors. The mechanisms of this regulation remain largely unsolved, but the inhibition of FtsZ polymerization by the nucleoid occlusion factor SlmA and filament stabilization by the widely conserved cross-linking protein ZapA are known to play key roles. It was recently described that FtsZ, SlmA and its target DNA sequences (SlmA-binding sequence (SBS)) form phase-separated biomolecular condensates, a type of structure associated with cellular compartmentalization and resistance to stress. Using biochemical reconstitution and orthogonal biophysical approaches, we show that FtsZ-SlmA-SBS condensates captured ZapA in crowding conditions and when encapsulated inside cell-like microfluidics microdroplets. We found that, through non-competitive binding, the nucleotide-dependent FtsZ condensate/polymer interconversion was regulated by the ZapA/SlmA ratio. This suggests a highly concentration-responsive tuning of the interconversion that favours FtsZ polymer stabilization by ZapA under conditions mimicking intracellular crowding. These results highlight the importance of biomolecular condensates as concentration hubs for bacterial division factors, which can provide clues to their role in cell function and bacterial survival of stress conditions, such as those generated by antibiotic treatment.


Assuntos
Acrilatos , Condensados Biomoleculares , Citocinese , Polímeros
7.
Int J Mol Sci ; 24(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36614239

RESUMO

Fundamental knowledge about cell-surface interactions can be applied in the development of wound dressings and scaffolds to encourage wounds to heal. As surfaces produced with acid-functionalised monomers encourage keratinocyte adhesion, proliferation and migration, whilst amine functionalisation enhances fibroblast proliferation and migration in vitro, standard care wound dressings were plasma-coated with either acrylic acid or allylamine and applied to 6 mm excisional wounds on the backs of mice to test their effectiveness in vivo. At day 3, the rate of wound healing was increased in mice treated with dressings that were plasma-coated with allylamine compared to uncoated dressings, with a significantly reduced wound area. However, healing may be impaired following prolonged treatment with allylamine-functionalised dressings, with delayed re-epithelialisation and increased cellularisation of the wound site at later timepoints. Acrylic acid functionalisation, however, offered no early improvement in wound healing, but wounds treated with these dressings displayed increased collagen deposition at day 7 post wounding. These results suggest that plasma polymerisation may allow for the development of new dressings which can enhance wound closure by directing cell behaviour, but that the application of these dressings may require a timed approach to enhance specific phases of the wound healing response.


Assuntos
Bandagens , Cicatrização , Camundongos , Animais , Acrilatos/farmacologia , Colágeno
9.
Biomacromolecules ; 24(2): 592-603, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36705942

RESUMO

Introducing vinyl groups onto the backbone of technical lignin provides an opportunity to create highly reactive renewable polymers suitable for radical polymerization. In this work, the chemical modification of softwood kraft lignin was pursued with etherification, followed by direct esterification with acrylic acid (AA). In the first step, phenolic hydroxyl and carboxylic acid groups were derivatized into aliphatic hydroxyl groups using ethylene carbonate and an alkaline catalyst. The lignin was subsequently fractionated using a downward precipitation method to recover lignin of defined molar mass and solubility. After recovery, the resulting material was then esterified with AA, resulting in lignin with vinyl functional groups. The first step resulted in approximately 90% of phenolic hydroxyl groups being converted into aliphatic hydroxyls, while the downward fractionation resulted in three samples of lignin with defined molar masses. For the esterification reaction, the weight ratio of reagents, reaction temperature, and reaction time were evaluated as factors that would influence the modification efficacy. 13C NMR spectroscopy analysis of lignin samples before and after esterification showed that the optimized reaction conditions could reach approximately 40% substitution of aliphatic hydroxyl groups. Both steps only used lignin and the modifying reagent (no solvent), with the possibility of recovery and reuse of the reagent by dilution and distillation. An additional second esterification step of the resulting lignin sample with acetic acid or propionic acid converted 90% of remaining hydroxyl groups into short-chain carbon aliphatic esters, making a hydrophobic material suitable for further copolymerization with synthetic hydrophobic monomers.


Assuntos
Ésteres , Lignina , Lignina/química , Ésteres/química , Acrilatos , Esterificação , Fenóis
10.
Biomater Sci ; 11(5): 1692-1703, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36626200

RESUMO

Orthopedic insoles is the most commonly used nonsurgical treatment method for the flatfoot. Polyurethane (PU) plays a crucial role in the manufacturing of orthopedic insoles due to its high wear resistance and elastic recovery. However, preparing orthopedic insoles with adjustable hardness, high-accuracy, and matches the plantar morphology is challenging. Herein, a liquid crystal display (LCD) three-dimensional (3D) printer was used to prepare the customized arch-support insoles based on photo-curable and elastic polyurethane acrylate (PUA) composite resins. Two kinds of photo-curable polyurethanes (DL1000-PUA and DL2000-PUA) were successfully synthesized, and a series of fast-photocuring polyurethane acrylate (PUA) composite resins for photo-polymerization 3D printing were developed. The effects of different acrylate monomers on the Shore hardness, viscosity, and mechanical properties of the PUA composite resins were evaluated. The PUA-3-1 composite resin exhibited low viscosity, optimal hardness, and mechanical properties. A deviation analysis was conducted to assess the accuracy of printed insole. Furthermore, the stress conditions of the PUA composite resin and ethylene vinyl acetate (EVA) under the weight load of healthy adults were compared by finite element analysis (FEA) simulation. The results demonstrated that the stress of the PUA composite resin and EVA were 0.152 MPa and 0.285 MPa, and displacement were 0.051 mm and 3.449 mm, respectively. These results indicate that 3D-printed arch-support insole based on photocurable PUA composite resin are high-accuracy, and can reduce plantar pressure and prevent insoles premature deformation, which show great potential in the physiotherapeutic intervention for foot disorders.


Assuntos
Pé Chato , Órtoses do Pé , Adulto , Humanos , Pé Chato/terapia , Poliuretanos/química , Dureza , Resinas Compostas/química , Glicóis , Acrilatos , Impressão Tridimensional
11.
Mol Pharm ; 20(3): 1624-1630, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36705398

RESUMO

Gastroretentive dosage forms are intended to stay inside the stomach for a long period of time while releasing an active pharmaceutical ingredient. Such systems may offer significant benefits for numerous drugs compared to other sustained release systems, such as improved pharmacokinetics/bioavailability and reduced intake frequency and thereby improved adherence to the medical therapy. However, there is no gastroretentive product on the market with proven reliable gastroretentive properties in humans. A major obstacle is the motility pattern of the stomach in the fasting state in humans, which reliably ensures gastric emptying of even large indigestible objects into the small intestine. One promising approach to avoid gastric emptying is adhesion of the drug delivery system to the gastric mucosa. In order to achieve mucoadhesive properties, minitablets containing Carbopol 71G NF were developed and compared to minitablets without adhesive properties. In a specialized mucoadhesive test system, the adhesion time was prolonged for adhesive minitablets (240 min) compared to non-adhesive minitablets (30 min). The in vivo transit behavior was investigated using magnetic resonance imaging in 11 healthy volunteers in fasted state in a crossover setup. It was found that the gastric residence time (GRT) of the adhesive minitablets (median of 37.5 min with IQR = 22.5-52.5) was statistically significantly prolonged compared to the non-adhesive minitablets (median of 7.5 with IQR = 7.5-22.5), indicating a delay in gastric emptying by adhesion to the gastric mucosa. However, the system needs further improvement to create a clinical benefit. Furthermore, it was observed that for 9 of 22 administrations (three minitablets were given simultaneously with every administration), the minitablets were not emptied together but showed different GRTs.


Assuntos
Acrilatos , Sistemas de Liberação de Medicamentos , Humanos , Sistemas de Liberação de Medicamentos/métodos , Estômago , Mucosa Gástrica , Adesivos , Esvaziamento Gástrico , Preparações de Ação Retardada
12.
J Chromatogr A ; 1688: 463713, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36535112

RESUMO

In this research report, the previously developed poly(carboxyethyl acrylate-co-ethylene glycol dimethacrylate) precursor monolith (referred to as carboxy monolith) is further exploited in the preparation of a chiral stationary phase for enantiomeric separations. The carboxy monolith precursor was subjected to post polymerization functionalization (PPF) with the chiral selector (S)-(-)-1-(2-naphthyl) ethylamine (NAS) at room temperature in the presence of N, N´-dicyclohexylcarbodiimide (DCC) in chloroform. The DCC, which is an organic soluble carbodiimide, permits the linkage for the amine functionality of the chiral ligand NAS to the carboxy group of the monolithic surface forming a stable amide linkage. The NAS column thus obtained allowed not only enantiomeric separations in the RP mode via its chiral site but also the separation of nonpolar species via its achiral functionality offering both hydrophobic and π-π interactions for aromatic compounds such toluene derivatives and polyaromatic hydrocarbons. The dual interaction sites (e.g., chiral, and achiral) of the NAS present a convenient column for the separations of slightly polar and nonpolar chiral and achiral solutes in the RP mode.


Assuntos
Eletrocromatografia Capilar , Eletrocromatografia Capilar/métodos , Ligantes , Acrilatos/química , Etilaminas
14.
Sci Bull (Beijing) ; 67(8): 794-802, 2022 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-36546232

RESUMO

Due to their great potential in wearable and portable electronics, flexible perovskite solar cells (FPSCs) have been extensively studied. The major challenges in the practical applications of FPSCs are efficiency, operational stability, and mechanical stability. Herein, we developed a facile approach by incorporating a cross-linking oligomer of trimethylolpropane ethoxylate triacrylate (TET) into perovskite films to simultaneously enhance the power conversion efficiency (PCE) and stability of FPSCs. A PCE of 20.32% was achieved, which are among the best results for the inverted FPSCs. Both mechanical and environmental stabilities were improved for the TET-incorporated FPSCs. In particular, the PCE retained approximately 87% of its initial value after 20,000 bending cycles at a radius of 4 mm. The inverted FPSCs retained 85% of the initial PCE after 500 h storage at 85 °C and 90% after 900 h continuous one-sun illumination. A joint experiment-theory analysis ascribed the underlying mechanism to the reduced defect densities, improved crystallinity, and stability of the perovskite absorbers on flexible substrates caused by TET incorporation.


Assuntos
Acrilatos , Compostos de Cálcio , Eletrônica
15.
Molecules ; 27(22)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36432000

RESUMO

This study focuses on the experimental and molecular-level investigation of epoxy acrylate formation. Epoxy acrylate vinyl ester resin was prepared by a reaction of diglycidyl ether of bisphenol-A-based epoxy resin and acrylic acid, using benzimidazole as a catalyst. It was confirmed that benzimidazole can effectively catalyze this reaction. FTIR analysis of the product revealed a simple addition esterification reaction between the epoxide group and carboxylic group of acrylic acid excluding the side reactions (e.g., etherification). DFT computational studies were performed to theoretically explore the insights of reaction mechanisms. The calculations revealed that the benzimidazole-catalyzed reaction dominates the uncatalyzed reaction. A comparison of calculated activation energies showed that concerted mechanisms are less significant in such reactions owing to their high activation barriers.


Assuntos
Acrilatos , Resinas Epóxi , Benzimidazóis , Catálise , Ésteres
16.
Int J Pharm ; 629: 122362, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379396

RESUMO

This research aimed to create new hydrophilic drug-in-adhesive patches for transdermal drug delivery. Poly(hydroxyethyl acrylate-co-itaconic acid)-catechol (PHI-cat) and hyaluronic acid (HA) were used as main components in the pressure-sensitive adhesive. Citric acid and aluminium hydroxide were exploited as crosslinking agents and ketoprofen was employed as a model delivering compound. The adhesive performance, physicochemical properties, drug-polymer interaction, drug crystallization, drug content, drug permeation through the skin, and coordination polymer network of the patches were investigated. In addition, skin irritation and adhesion potential in human subjects were assessed. Due to the ability of catechol groups to form interaction with the skin tissue, the patches containing PHI-cat and HA offered a considerably greater adhesion ability to human skin compared with the patches without catechol and commercial patches. Furthermore, the patches had good physical and chemical stability. Therefore, these catechol-functionalized patches may be potential transdermal drug delivery systems with excellent adhesive properties for the delivery of a drug through the skin.


Assuntos
Cetoprofeno , Humanos , Adesivos/química , Ácido Hialurônico , Preparações Farmacêuticas , Administração Cutânea , Acrilatos/química , Catecóis , Polímeros/química , Adesivo Transdérmico
17.
Acta Derm Venereol ; 102: adv00818, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36317860

RESUMO

Artificial nail modelling systems (ANMS), encompassing artificial nails and long-lasting nail polish, are sources of acrylate exposure in beauticians and users of ANMS. Hairdressers' exposure to ANMS from self-use and occupational exposure is currently unknown. In 2020 a questionnaire was sent to all hairdressers graduating during 2008 to 2018 in Denmark (n = 4,830). Self-use of ANMS was reported by 87.6% of respondents (1,251/1,428), and application of ANMS to others was reported by 22.1% (316/1,428). Of these, application to others was performed in a salon by 37.1% (109/294), privately by 51.0% (150/294) and in both settings by 11.9% (35/294). Compliance with glove use was seen in 23.0% (67/291) among those applying ANMS to others. Among hairdressers exposed to ANMS, 4.3% (52/1,218) reported ANMS-related hand eczema. Being a trained beautician (adjusted odds ratio 3.26, 95% confidence interval 1.06-9.99) and having had a positive patch-test to acrylates (adjusted odds ratio 7.70, 95% confidence interval 1.44-41.13) were associated with ANMS-related hand dermatitis. In conclusion, hairdressers have a high prevalence of exposure to ANMS and ANMS-related hand dermatitis. Compliance with glove use when applying ANMS to others is poor. Patch-testing with acrylates is valuable in the diagnostic work-up of hand eczema in hairdressers.


Assuntos
Dermatite Ocupacional , Eczema , Exposição Ocupacional , Humanos , Dermatite Ocupacional/diagnóstico , Dermatite Ocupacional/epidemiologia , Dermatite Ocupacional/etiologia , Unhas , Polônia , Eczema/epidemiologia , Exposição Ocupacional/efeitos adversos , Acrilatos , Dinamarca/epidemiologia
18.
Chem Res Toxicol ; 35(11): 2160-2167, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36318224

RESUMO

The objective of this work was to study the effect of octocrylene on Stylophora pistillata and to compare the metabolomic response of this coral species to that obtained with Pocillopora damicornis. When S. pistillata coral was exposed to octocrylene, it accumulated octocrylene derivatives similar to P. damicornis. Octocrylene-fatty acid conjugates were found, as well as octocrylene heterosides. Furthermore, the tissue concentrations of various acylcarnitines and three sphingoid bases increased significantly. This phenomenon was indicative of mitochondrial dysfunction and the induction of cellular senescence processes in exposed corals. Overall, the responses of the two corals to octocrylene pollution were consistent. The proven impact of octocrylene on a second coral species suggests that potential environmental octocrylene pollution could impact many reef-building species. Furthermore, this work demonstrates that octocrylene may be modified in vivo by many organisms and that levels of octocrylene contamination in the food chain have probably been underestimated until now.


Assuntos
Antozoários , Animais , Antozoários/fisiologia , Acrilatos , Senescência Celular , Mitocôndrias
19.
Se Pu ; 40(10): 929-936, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36222256

RESUMO

Pesticides are used in the agricultural production process to ensure the yield and quality of agricultural products. However, in recent years, environmental pollution issues caused by pesticide residues have sparked widespread concern in society. It is important to develop convenient and efficient approaches to detect and monitor pesticide residues. In this study, targeting benzoylurea insecticides (BUs), polyamidoamine dendrimer-functionalized silica nanocomposite with polydopamine coating (SiO2-PAMAM-PDA) was designed and successfully synthesized. First, monodisperse silica nanoparticles were prepared by the hydrolysis of tetraethyl orthosilicate (TEOS) in mixed solution of ethanol, water and ammonia. The silane coupling agent (3-aminopropyl)triethoxysilane was then employed to introduce amino groups into the silica. Silica with the zeroth generation of polyamidoamine (PAMAM) modification (SiO2-PAMAM-G0) was obtained through Michael addition reaction of methyl acrylate. Ethylenediamine was added to polymerize with methyl acrylate using an amidation reaction to form the first-generation PAMAM (SiO2-PAMAM-G1). Finally, by polymerizing dopamine under alkaline conditions (pH=8.5), the SiO2-PAMAM-G1 was coated with PDA. Thus, the final product named SiO2-PAMAM-PDA was obtained. The composite was characterized using a transmission electron microscope (TEM) and an increase in surface roughness indicated the successful grafting of PDA coating. Dopamine structure contains abundant benzene rings and amino and hydroxyl groups. It could bind with BUs through multiple secondary interactions, such as hydrogen bond and π-π stacking interaction. Therefore, the introduction of PDA could effectively enhance the affinity of the material toward benzoylurea insecticides. The prepared nanocomposites were used as sorbents in a dispersive micro solid-phase extraction approach (D-µ-SPE). The established approach was employed to extract and enrich the BUs in water samples before high-performance liquid chromatography (HPLC) analysis. Diflubenzuron, triflumuron, hexaflumuron, and teflubenzuron were chosen as target analytes. The following was a typical D-µ-SPE procedure. The prepared adsorbents measuring 40 mg were first dispersed in an 8-mL sample solution containing 150 g/L NaCl. The dispersion was assisted by 120-s vortexing to ensure full contact between the SiO2-PAMAM-PDA and the targets. Next, the adsorbents were separated from the liquid phase by 4-min centrifugation (5000 r/min). Thereafter, the adsorbed benzoylureas were eluted using 1 mL acetonitrile as desorption solvent by 120-s vortexing. Separated by centrifugation, the eluate was dried under a mild nitrogen stream. The solid remains were redissolved in 0.1 mL of acetonitrile, filtered by filter membrane (0.22 µm), and then analyzed by HPLC. The experimental conditions in the D-µ-SPE process could have a great impact on the extraction efficiency. Experimental conditions were optimized using a single factor optimization approach to further enhance the extraction recoveries. The optimized conditions included adsorbent amount, extraction time, desorption solvent type, desorption solvent volume, desorption time, and NaCl addition amount. Under the optimal conditions, a linearity range of 10-500 µg/L and limits of detection (LODs, S/N=3) of 1.1-2.1 µg/L were obtained. The extraction recoveries and relative standard deviations (RSDs) of the four BUs were 82.8%-94.1% and 2.1%-8.0%, respectively. The established approach was compared with reported approaches targeting benzoylurea insecticides. It was discovered that this approach consumed less sample, material, organic solvent, and pretreatment time. It provided a more rapid and green choice for the determination of benzoylurea pesticides. To determine the applicability, the proposed approach was applied to analyze the four benzoylurea insecticides in three river water samples. The real water samples were pretreated using the developed approach ahead of instrumental analysis, and no benzoylurea pesticides residue was detected. Next, standard addition experiments were performed under three spiking levels, including 15, 50, and 200 µg/L. The established approach had good accuracy and feasibility with satisfactory recoveries (69.5%-99.4%) and RSDs (0.2%-9.5%).


Assuntos
Dendrímeros , Diflubenzuron , Inseticidas , Nanocompostos , Resíduos de Praguicidas , Acetonitrilas/análise , Acrilatos , Amônia/análise , Benzeno/análise , Cromatografia Líquida de Alta Pressão , Dendrímeros/análise , Diflubenzuron/análise , Dopamina/análise , Etanol/análise , Etilenodiaminas/análise , Indóis , Inseticidas/análise , Nanocompostos/análise , Nitrogênio/análise , Resíduos de Praguicidas/análise , Poliaminas , Polímeros , Silanos/análise , Dióxido de Silício/análise , Cloreto de Sódio/análise , Extração em Fase Sólida , Solventes/análise , Água/análise
20.
BMC Plant Biol ; 22(1): 486, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36224553

RESUMO

BACKGROUND: The timing of bud break is very important for the flowering and fruiting of longan. To obtain new insights into the underlying regulatory mechanism of bud break in longan, a comparative analysis was conducted in three flower induction stages of two longan varieties with opposite flowering phenotypes by using isobaric tags for relative and absolute quantification (iTRAQ). RESULTS: In total, 3180 unique proteins were identified in 18 samples, and 1101 differentially abundant proteins (DAPs) were identified. "SX" ("Shixia"), a common longan cultivated variety that needs an appropriate period of low temperatures to accumulate energy and nutrients for flower induction, had a strong primary inflorescence, had a strong axillary inflorescence, and contained high contents of sugars, and most DAPs during the bud break process were enriched in assimilates and energy metabolism. Combined with our previous transcriptome data, it was observed that sucrose synthase 6 (SS6) and granule-bound starch synthase 1 (GBSSI) might be the key DAPs for "SX" bud break. Compared to those of "SX", the primary inflorescence, axillary inflorescence, floral primordium, bract, and prophyll of "SJ" ("Sijimi") were weaker. In addition, light, rather than a high sugar content or chilling duration, might act as the key signal for triggering bud break. In addition, catalase isozyme 1, an important enzyme in the redox cycle, and RuBisCO, a key enzyme in the Calvin cycle of photosynthetic carbon assimilation, might be the key DAPs for SJ bud break. CONCLUSION: Our results present a dynamic picture of the bud break of longan, not only revealing the temporal specific expression of key candidate genes and proteins but also providing a scientific basis for the genetic improvement of this fruit tree species.


Assuntos
Proteômica , Sintase do Amido , Acrilatos , Carbono , Catalase/genética , Flores/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Isoenzimas/genética , Ribulose-Bifosfato Carboxilase/genética , Sapindaceae , Sintase do Amido/genética , Açúcares
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