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1.
Physiol Plant ; 175(1): e13848, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36628548

RESUMO

During fern spore germination, lipid hydrolysis primarily provides the energy to activate their metabolism. In this research, fatty acids (linoleic, oleic, palmitic and stearic) were quantified in the spores exposed or not to priming (hydration-dehydration treatments). Five fern species were investigated, two from xerophilous shrubland and three from a cloud forest. We hypothesised that during the priming hydration phase, the fatty acids profile would change in concentration, depending on the spore type (non-chlorophyllous and crypto-chlorophyllous). The fatty acid concentration was determined by gas chromatograph-mass spectrometer. Chlorophyll in spores was vizualised by epifluorescence microscopy and quantified by high-resolution liquid chromatography with a DAD-UV/Vis detector. Considering all five species and all the treatments, the oleic acid was the most catabolised. After priming, we identified two patterns in the fatty acid metabolism: (1) in non-chlorophyllous species, oleic, palmitic, and linoleic acids were catabolised during imbibition and (2) in crypto-chlorophyllous species, these fatty acids increased in concentration. These patterns suggest that crypto-chlorophyllous spores with homoiochlorophylly (chlorophyll retained after drying) might not require the assembly of new photosynthetic apparatus during dark imbibition. Thus, these spores might require less energy from pre-existing lipids and less fatty acids as 'building blocks' for cell membranes than non-chlorophyllous spores, which require de novo synthesis and structuring of the photosynthetic apparatus.


Assuntos
Ácidos Graxos , Gleiquênias , Ácidos Graxos/metabolismo , Gleiquênias/metabolismo , Esporos/fisiologia , Metabolismo dos Lipídeos , Ácido Oleico/metabolismo , Ácidos Esteáricos/metabolismo , Ácido Palmítico/metabolismo
2.
Molecules ; 28(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36903263

RESUMO

Ochratoxin A (OTA) is considered one of the main mycotoxins responsible for health problems and considerable economic losses in the feed industry. The aim was to study OTA's detoxifying potential of commercial protease enzymes: (i) Ananas comosus bromelain cysteine-protease, (ii) bovine trypsin serine-protease and (iii) Bacillus subtilis neutral metalloendopeptidase. In silico studies were performed with reference ligands and T-2 toxin as control, and in vitro experiments. In silico study results showed that tested toxins interacted near the catalytic triad, similar to how the reference ligands behave in all tested proteases. Likewise, based on the proximity of the amino acids in the most stable poses, the chemical reaction mechanisms for the transformation of OTA were proposed. In vitro experiments showed that while bromelain reduced OTA's concentration in 7.64% at pH 4.6; trypsin at 10.69% and the neutral metalloendopeptidase in 8.2%, 14.44%, 45.26% at pH 4.6, 5 and 7, respectively (p < 0.05). The less harmful α-ochratoxin was confirmed with trypsin and the metalloendopeptidase. This study is the first attempt to demonstrate that: (i) bromelain and trypsin can hydrolyse OTA in acidic pH conditions with low efficiency and (ii) the metalloendopeptidase was an effective OTA bio-detoxifier. This study confirmed α-ochratoxin as a final product of the enzymatic reactions in real-time practical information on OTA degradation rate, since in vitro experiments simulated the time that food spends in poultry intestines, as well as their natural pH and temperature conditions.


Assuntos
Micotoxinas , Ocratoxinas , Animais , Bovinos , Ocratoxinas/análise , Bromelaínas , Simulação de Acoplamento Molecular , Tripsina , Ração Animal/análise , Metaloendopeptidases
3.
Molecules ; 27(1)2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35011491

RESUMO

Mangifera indica can generate up to 60% of polluting by-products, including peels. However, it has been shown that flavonoids and mangiferin are mainly responsible for the antioxidant, anti-inflammatory, and antibacterial activities closely related to the wound-healing process. The chemical composition of MEMI (methanolic extract of M. indica) was analyzed by HPLC-DAD, as well as concentrations of total phenol (TPC) and flavonoids (TFC) and antioxidant activity (SA50). Wound-healing efficacy was determined by measurements of wound contraction, histological analysis, and tensiometric method; moreover, anti-inflammatory, antibacterial, and acute dermal toxicity (OECD 402) were also evaluated. Phenol, resorcinol, conjugated resorcinol, and mangiferin were detected. TPC, TFC, and SA50 were 136 mg GAE/g, 101.66 mg QE/g, and 36.33 µg/mL, respectively. Tensile strength and wound contraction closure did not show significant differences between MEMI and dexpanthenol groups. Histological analysis (after 14 days) shows a similar architecture between MEMI treatment and normal skin. MEMI exhibits a reduction in edema. Staphylococcus epidermidis had an MIC of 2 mg/mL, while Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli reached 4 mg/mL. The MEMI showed no signs of toxicity. Therefore, this study demonstrates multiple targets that flavonoids and mangiferin of MEMI may present during the healing process.


Assuntos
Mangifera/química , Extratos Vegetais , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões , Animais , Modelos Animais de Doenças , Flavonoides/química , Flavonoides/farmacologia , Masculino , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ferimentos e Lesões/tratamento farmacológico , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/microbiologia , Xantonas/química , Xantonas/farmacologia
4.
Mutagenesis ; 35(4): 299-310, 2020 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-31793639

RESUMO

Chagas disease, caused by the protozoan Trypanosoma cruzi, has increased in the world due to migration, travelling and climate change; at present, the principal problem is that common trypanocidal agents have resulted in toxic or inconvenient side effects. We tested for genotoxicity in the standard (ST) and high bioactivation (HB) crosses of Drosophila wing somatic mutation and recombination test, four novel trypanocidal agents derived from 2, 4, 6-triaminquinazoline (TAQ): 2,4-diamino-6 nitro-1,3 diazonaftalene (S-1QN2-1), 2,4-diacetamino-6-amino 1,3 diazonaftalene (D-1), N6-(4,methoxybenzyl)quinazoline-2,4,6-triamine (GHPM) and N6-[4-(trifluoromethoxy)benzyl]quinazoline-2,4,6-triamine (GHPMF) at 1.9, 3.9, 7.9 and 15 µM, respectively. Also, high-pressure liquid chromatography (HPLC) analysis was run to determine the remanence of either drug in flare, and Oregon R(R)-flare flies emerged from treated larvae. S-1QN2-1 showed genotoxicity only in the ST cross, increasing the small, large and total spot frequencies at all concentrations and twin spots only at 1.9 µM; D-1 and GHPM showed significant increments of large spots only at 15 µM in the ST cross; GHPMF was not genotoxic at any concentration or either cross. In the mwh clones accumulated distribution frequencies analysis, associated with disrupted cell division, S-1QN2-1 caused alterations in the ST cross at all concentrations but only at 15 µM in the HB cross; D-1 caused alterations at 3.9, 7.9 and 15 µM in the ST cross and at 1.9 and 15 µM in the HB cross; GHPM caused alterations at 7.9 and 15 µM in the ST cross and also at 1.9, 3.9 and 7.9 µM in the HB cross; GHPMF caused those alterations at all concentrations in the ST cross and at 1.9, 3.9 and 7.9 µM in the HB cross. The HPLC results indicated no traces of either agent in the flare and Oregon R(R)-flare flies. We conclude that S-1QN2-1 is clearly genotoxic, D-1 and GHPM have an unclear genotoxicity and GHPMF was not genotoxic; all quinazoline derivatives disrupted cell division. GHPMF is a good candidate to be tested in other genotoxicity and cytotoxic bioassays. The differences in the genotoxic activity of these trypanocidal agents are correlated with differences in their chemical structure.


Assuntos
Dano ao DNA , Drosophila melanogaster/efeitos dos fármacos , Mutação , Quinazolinas/farmacologia , Tripanossomicidas/farmacologia , Animais , DNA/efeitos dos fármacos , Drosophila melanogaster/genética , Testes de Mutagenicidade , Recombinação Genética , Asas de Animais
5.
Small ; 14(21): e1704111, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29667293

RESUMO

Efficient magnetic reactive oxygen species (ROS) formation enhancing agents after X-ray treatment are realized by functionalizing superparamagnetic magnetite (Fe3 O4 ) and Co-ferrite (CoFe2 O4 ) nanoparticles with self-assembled monolayers (SAMs). The Fe3 O4 and CoFe2 O4 nanoparticles are synthesized using Massart's coprecipitation technique. Successful surface modification with the SAM forming compounds 1-methyl-3-(dodecylphosphonic acid) imidazolium bromide, or (2-{2-[2-hydroxy-ethoxy]-ethoxy}-ethyl phosphonic acid provides biocompatibility and long-term stability of the Fe3 O4 and CoFe2 O4 nanoparticles in cell media. The SAM-stabilized ferrite nanoparticles are characterized with dynamic light scattering, X-ray powder diffraction, a superconducting quantum interference device, Fourier transform infrared attenuated total reflectance spectroscopy, zeta potential measurements, and thermogravimetric analysis. The impact of the SAM-stabilized nanoparticles on the viability of the MCF-7 cells and healthy human umbilical vein endothelial cells (HUVECs) is assessed using the neutral red assay. Under X-ray exposure with a single dosage of 1 Gy the intracellular SAM stabilized Fe3 O4 and CoFe2 O4 nanoparticles are observed to increase the level of ROS in MCF-7 breast cancer cells but not in healthy HUVECs. The drastic ROS enhancement is associated with very low dose modifying factors for a survival fraction of 50%. This significant ROS enhancement effect by SAM-stabilized Fe3 O4 and CoFe2 O4 nanoparticles constitutes their excellent applicability in radiation therapy.


Assuntos
Materiais Biocompatíveis/química , Neoplasias da Mama/radioterapia , Cobalto/química , Compostos Férricos/química , Nanopartículas de Magnetita/química , Espécies Reativas de Oxigênio/metabolismo , Água/química , Sobrevivência Celular , Cobalto/análise , Difusão Dinâmica da Luz , Feminino , Fluoresceínas/química , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Imidazóis/química , Íons , Nanopartículas de Magnetita/ultraestrutura , Eletricidade Estática
6.
Chemistry ; 24(51): 13589-13595, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-29992658

RESUMO

We report on the development of a supramolecular nanocarrier concept that allows for the encapsulation and separation of small apolar molecules from water. The nanocarriers consist of shell-by-shell-coated nanoparticles such as TiO2 and ferromagnetic Fe3 O4 . The first ligand shell is provided by covalently bound hexadecyl phosphonic acid (PAC16 ) and the second shell by noncovalently assembled amphiphiles rendering the hybrid architecture soluble in water. Agitation of these constructs with water containing the hydrocarbons G1-G4, the fluorescent marker G5, the polychlorinated biphenyl PCB 77, or crude oil leads to a very efficient uptake (up to 411 %) of the apolar contaminant. In case of the hybrids containing a Fe3 O4 core, straightforward phase separation by the action of an external magnet is provided. The load can easily be released by a final treatment with an organic solvent.

7.
Chemistry ; 22(38): 13506-12, 2016 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-27439653

RESUMO

The adsorption, desorption, co-adsorption, and exchange behavior of phosphonic acid, carboxylic acid, and catechol derivatives on the surface of titanium oxide (anatase) nanoparticles are investigated. Thermogravimetric analysis provides a facile and fast-track quantitative determination of the wet-chemical monolayer adsorption constants and grafting densities of ten adsorbates, all under neutral pH conditions. This characterization protocol allows straightforward quantification of the relevant thermodynamic data of ligand adsorption and a comparison of ligand adsorption strengths. The reported procedure is proposed as a universal tool and it should be applicable to many other colloidal metal oxide materials. Moreover, the determined values for the adsorption constants and the monolayer grafting densities provide a toolbox for the assessment of the adsorbates' behavior in desorption, exchange, and co-adsorption equilibria. This versatile evaluation procedure will help to identify optimal monolayer-surface combinations and to evaluate critical parameters, such as monolayer robustness, ligand exchange rates, or targeted mixed assembly of functionalities.

8.
Chemistry ; 21(40): 14030-5, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26274348

RESUMO

The facile assembly of shell-by-shell (SbS)-coated nanoparticles [TiO2-PAC16]@shell 1-7 (PAC16 = hexadecylphosphonic acid), which are soluble in water and can be isolated as stable solids, is reported. In these functional architectures, an umpolung of dispersibility (organic apolar versus water) was accomplished by the noncovalent binding of ligands 1-7 to titania nanoparticles [TiO2-PAC16] containing a first covalent coating with PAC16. Ligands 1-7 are amphiphilic and form the outer second shell of [TiO2-PAC16]@shell 1-7. The tailor-designed dendritic building blocks 3-5 contain negative and positive charges in the same molecule, and ligands 6 and 7 contain a perylenetetracarboxylic acid dimide (PDI) core (6/7) as a photoactive reporter component. In the redox and photoactive system [TiO2-PAC16]@shell 7, electronic communication between the inorganic core to the PDI ligands was observed.

9.
Angew Chem Int Ed Engl ; 54(32): 9235-8, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26088393

RESUMO

A method for the region-selective deposition of nanoparticles (NPs) by the Huisgen 1,3-dipolar cycloaddition is presented. The approach enables defined stacking of various oxide NPs in any order with control over layer thickness. Thereby the reaction is performed between a substrate, functionalized with a self-assembled monolayer of an azide-bearing phosphonic acid (PA) and aluminum oxide (AlO(x)) NPs functionalized with an alkyne bearing PA. The layer of alkyne functionalized AlO(x) NPs is then used as substrate for the deposition of azide-functionalized indium tin oxide (ITO) NPs to provide a binary stack. This progression is then conducted with alkyne-functionalized CeO2 NPs, yielding a ternary stack of NPs with three different NP cores. The stacks are characterized by AFM and SEM, defining the region-selectivity of the deposition technique. Finally, these assemblies have been tested in devices as a dielectric to form a capacitor resulting in a dramatic increase in the measured capacitance.

10.
Plants (Basel) ; 13(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38202439

RESUMO

When colonizing new ranges, plant populations may benefit from the absence of the checks imposed by the enemies, herbivores, and pathogens that regulated their numbers in their original range. Therefore, rates of plant damage or infestation by natural enemies are expected to be lower in the new range. Exposing both non-native and native plant populations in the native range, where native herbivores are present, can be used to test whether resistance mechanisms have diverged between populations. Datura stramonium is native to the Americas but widely distributed in Spain, where populations show lower herbivore damage than populations in the native range. We established experiments in two localities in the native range (Mexico), exposing two native and two non-native D. stramonium populations to natural herbivores. Plant performance differed between the localities, as did the abundance of the main specialist herbivore, Lema daturaphila. In Teotihuacán, where L. daturaphila is common, native plants had significantly more adult beetles and herbivore damage than non-native plants. The degree of infestation by the specialist seed predator Trichobaris soror differed among populations and between sites, but the native Ticumán population always had the lowest level of infestation. The Ticumán population also had the highest concentration of the alkaloid scopolamine. Scopolamine was negatively related to the number of eggs deposited by L. daturaphila in Teotihuacán. There was among-family variation in herbivore damage (resistance), alkaloid content (scopolamine), and infestation by L. daturaphila and T. soror, indicating genetic variation and potential for further evolution. Although native and non-native D. stramonium populations have not yet diverged in plant resistance/constitutive defense, the differences between ranges (and the two experimental sites) in the type and abundance of herbivores suggest that further research is needed on the role of resource availability and adaptive plasticity, specialized metabolites (induced, constitutive), and the relationship between genealogical origin and plant defense in both ranges.

11.
Toxins (Basel) ; 15(7)2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37505739

RESUMO

Aluminosilicates are adsorbents able to bind mycotoxins, and their chemical modification increases their affinity to adsorb low-polarity mycotoxins. To further investigate if the inclusion of salts in bentonite modifies its adsorptive capacity, we studied T-2 toxin adsorption in natural bentonite (NB) and when modified with quaternary ammonium salts differing in polarity and chain length: myristyl trimethyl ammonium bromide (B14), cetyl trimethyl ammonium bromide (B16) and benzyl dimethyl stearyl ammonium chloride (B18). The results showed that quaternary salts made bentonite: displace monovalent (Na+1, K+1) and divalent (Mg+2, Ca+2) ions; reduce its porosity; change its compaction and structure, becoming more crystalline and ordered; and modify the charge balance of sheets. T-2 adsorption was higher in all modified materials compared to NB (p ≤ 0.0001), and B16 (42.96%) better adsorbed T-2 compared to B18 (35.80%; p = 0.0066). B14 (38.40%) showed no differences compared to B16 and B18 (p > 0.05). We described the T-2 adsorption mechanism in B16, in which hydrogen bond interactions, Van der Waals forces and the replacement of the salt by T-2 were found. Our results showed that interaction types due to the inclusion in B16 might be more important than the hydrocarbon chain length to improve the adsorptive capacity of bentonite.


Assuntos
Toxina T-2 , Poluentes Químicos da Água , Bentonita/química , Adsorção , Sais , Cátions , Poluentes Químicos da Água/química
12.
Toxins (Basel) ; 15(6)2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37368659

RESUMO

Zearalenone (ZEN) is a non-steroidal mycoestrogen produced by the Fusarium genus. ZEN and its metabolites compete with 17-beta estradiol for cytosolic estrogen receptors, causing reproductive alterations in vertebrates. ZEN has also been associated with toxic and genotoxic effects, as well as an increased risk for endometrial adenocarcinomas or hyperplasia, breast cancer, and oxidative damage, although the underlying mechanisms remain unclear. Previous studies have monitored cellular processes through levels of transcripts associated with Phase I Xenobiotic Metabolism (Cyp6g1 and Cyp6a2), oxidative stress (hsp60 and hsp70), apoptosis (hid, grim, and reaper), and DNA damage genes (Dmp53). In this study, we evaluated the survival and genotoxicity of ZEN, as well as its effects on emergence rate and fecundity in Drosophila melanogaster. Additionally, we determined levels of reactive oxygen species (ROS) using the D. melanogaster flare and Oregon R(R)-flare strains, which differ in levels of Cyp450 gene expression. Our results showed that ZEN toxicity did not increase mortality by more than 30%. We tested three ZEN concentrations (100, 200, and 400 µM) and found that none of the concentrations were genotoxic but were cytotoxic. Taking into account that it has previously been demonstrated that ZEN administration increased hsp60 expression levels and apoptosis gene transcripts in both strains, the data agree with an increase in ROS and development and fecundity alterations. Since Drosophila lacks homologous genes for mammalian estrogen receptors alpha and beta, the effects of this mycotoxin can be explained by a mechanism different from estrogenic activity.


Assuntos
Zearalenona , Animais , Zearalenona/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo , Dano ao DNA , Fertilidade , Mamíferos/metabolismo
13.
Nanomicro Lett ; 12(1): 27, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34138255

RESUMO

In recent years, solution-processible semiconductors with perovskite or perovskite-inspired structures have been extensively investigated for optoelectronic applications. In particular, silver-bismuth-halides have been identified as especially promising because of their bulk properties and lack of heavily toxic elements. This study investigates the potential of Ag2BiI5 for near-infrared (NIR)-blind visible light photodetection, which is critical to emerging applications (e.g., wearable optoelectronics and the Internet of Things). Self-powered photodetectors were realized and provided a near-constant ≈ 100 mA W-1 responsivity through the visible, a NIR rejection ratio of > 250, a long-wavelength responsivity onset matching standard colorimetric functions, and a linear photoresponse of > 5 orders of magnitude. The optoelectronic characterization of Ag2BiI5 photodetectors additionally revealed consistency with one-center models and the role of the carrier collection distance in self-powered mode. This study provides a positive outlook of Ag2BiI5 toward emerging applications on low-cost and low-power NIR-blind visible light photodetector.

14.
ACS Nano ; 14(10): 14036-14046, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-32924510

RESUMO

The development of ultralow-power and easy-to-fabricate electronics with potential for large-scale circuit integration (i.e., complementary or complementary-like) is an outstanding challenge for emerging off-the-grid applications, e.g., remote sensing, "place-and-forget", and the Internet of Things. Herein we address this challenge through the development of ambipolar transistors relying on solution-processed polymer-sorted semiconducting carbon nanotube networks (sc-SWCNTNs) operating in the deep-subthreshold regime. Application of self-assembled monolayers at the active channel interface enables the fine-tuning of sc-SWCNTN transistors toward well-balanced ambipolar deep-subthreshold characteristics. The significance of these features is assessed by exploring the applicability of such transistors to complementary-like integrated circuits, with respect to which the impact of the subthreshold slope and flatband voltage on voltage and power requirements is studied experimentally and theoretically. As demonstrated with inverter and NAND gates, the ambipolar deep-subthreshold sc-SWCNTN approach enables digital circuits with complementary-like operation and characteristics including wide noise margins and ultralow operational voltages (≤0.5 V), while exhibiting record-low power consumption (≤1 pW/µm). Among thin-film transistor technologies with minimal material complexity, our approach achieves the lowest energy and power dissipation figures reported to date, which are compatible with and highly attractive for emerging off-the-grid applications.

15.
Nat Prod Res ; 34(13): 1942-1946, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30724587

RESUMO

The effect of exogenous application of jasmonic acid (JA) on the concentration of main terpenes and density of glandular trichomes was investigated in the Mexican oregano, propagated from seeds from 3 localities. JA 1 mM was applied locally and to the whole plant. JA locally applied increased the number of trichomes, with a mean of 20 trichomes more with respect to the controls in plants from Tecomavaca and Zapotitlán Salinas, and significantly increased the thymol concentration by 185% systemically and 255% locally, compared to the control. JA applied to the whole plant decreased the number of trichomes and increased the concentration of caryophyllene from 0.79 to 1.7 mg g-1, and α-caryophyllene from 0.3 to 0.8 mg g-1 in plants from San Rafael with reference to water control. The results suggest a plasticity of morphologic and phytochemical responses, and a potential use of JA to improve phenolic monoterpenes and sesquiterpenes production.


Assuntos
Ciclopentanos/farmacologia , Oxilipinas/farmacologia , Terpenos/análise , Tricomas/efeitos dos fármacos , Verbenaceae/efeitos dos fármacos , Lippia , México , Sesquiterpenos Monocíclicos , Monoterpenos/análise , Origanum/efeitos dos fármacos , Sesquiterpenos Policíclicos/análise , Timol/análise
16.
ACS Appl Mater Interfaces ; 11(44): 41531-41543, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31597420

RESUMO

Silver ink is the most widely used conductive material for printing electrodes in the fabrication of all-printed ion gel gated transistors because of their high conductivity and low cost. However, electrochemical instability of printed silver electrodes is generally one of the biggest issues, whether it is in air where silver gets oxidized or in a moisture environment where electrochemical migration occurs. Notwithstanding, the electrochemical stability of printed silver electrodes in ion gel medium has not been studied so far. In this work, we studied the electrochemical instabilities of printed silver electrodes in fully printed ion gel gated single-walled carbon nanotube (SWCNT) thin-film transistors (TFTs) and developed some strategies to overcome these issues. All-printed ion gel-based p-type SWCNT TFTs were employed to investigate the impact of electrochemical instabilities on the electrical behavior of printed SWCNT TFTs. The results have demonstrated that printed silver was unstable at anodic and cathodic polarization because of the corrosion by the ionic liquid. Besides, anodic corrosion of silver source/drain electrodes was shown to be responsible for the electrical failure of printed SWCNT TFTs in both the linear and saturated regime. These issues were completely resolved when preventing printed silver electrodes from coming into direct contact with ion gels. For example, ion gels were partially printed in device channels to avoid contacting the printed silver source and drain electrodes. At the same time, silver side-gate electrodes were replaced by inkjet-printed PEDOT:PSS electrodes to avoid gate electrode-related instabilities. Consequently, all-printed electrochemically stable SWCNT TFTs fabricated were obtained with enhanced performance of higher ION/IOFF ratios (105 to 106), smaller subthreshold slopes (∼70 mV/dec), and smaller hysteresis (ΔV = 0.025 V) at gate voltages from 1.2 to -0.5 V. Additionally, the polarity of all-printed SWCNT TFTs was converted from the p-channel to ambipolar while achieving lower leakage currents.

17.
ChemistryOpen ; 7(4): 277, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29657912

RESUMO

Invited for this month's cover picture is the group of Prof. Dr. Andreas Hirsch from Friedrich Alexander University (Germany). The cover picture shows shell-by-shell coated nanoparticle 'chameleons'-wet-chemically surface-modified nanoparticles that can reversibly adjust their dispersibility to entirely orthogonal solvent environments. Read the full text of their Full Paper at https://doi.org/10.1002/open.201800011.

18.
ChemistryOpen ; 7(4): 282-287, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29657914

RESUMO

We describe a universal wet-chemical shell-by-shell coating procedure resulting in colloidal titanium dioxide (TiO2) and iron oxide (Fe3O4) nanoparticles with dynamically and reversibly tunable surface energies. A strong covalent surface functionalization is accomplished by using long-chained alkyl-, triethylenglycol-, and perfluoroalkylphosphonic acids, yielding highly stabilized core-shell nanoparticles with hydrophobic, hydrophilic, or superhydrophobic/fluorophilic surface characteristics. This covalent functionalization sequence is extended towards a second noncovalent attachment of tailor-made nonionic amphiphilic molecules to the pristine coated core-shell nanoparticles via solvophobic (i.e. either hydrophobic, lipophobic, or fluorophobic) interactions. Thereby, orthogonal tuning of the surface energies of nanoparticles via noncovalent interactions is accomplished. As a result, this versatile bilayer coating process enables reversible control over the colloidal stability of the metal oxide nanoparticles in fluorocarbons, hydrocarbons, and water.

19.
Artigo em Inglês | MEDLINE | ID: mdl-30538760

RESUMO

In the Valley of Tehuacan-Cuicatlan, Cyrtocarpa procera and Bursera morelensis are located and are used in traditional medicine. In this research, several biological properties were evaluated. The methanol extracts of C. procera (MeCp) and B. morelensis (MeBm) were obtained by maceration. The antibacterial activities of the extracts were evaluated by the Kirby-Baüer disc-diffusion method. The wound healing activity was evaluated by histopathological analysis. Both extracts had a bacteriostatic effect in the Staphylococcus aureus (MeCp MIC = 0.25 mg/mL and MeBm MIC = 1 mg/mL) and the Vibrio cholerae (MeCp MIC = 1 mg/mL and MeBm MIC = 4 mg/mL). Both extracts demonstrated a wound healing efficacy similar to the reference standard (Recoveron). They also showed a high antioxidant capacity (MeCp SC50 = 5.75 µg/mL and MeBm SC50 = 4.27 µg/mL). These results are related to the concentration of phenols (MeCp = 166 and MeBm = 236.6 mg GAe/g) and flavonoids of MeCp = 16 and MeBm = 22 µg Qe/g. Both extracts, acting in a similar way in microorganisms that cause infection thanks to their antioxidant activity, favor the healing of wounds. This is the first study in which the biological properties of these two species are compared.

20.
Rev. colomb. neumol ; 34(2): 25-37, July-Dec. 2022.
Artigo em Inglês | LILACS, COLNAL | ID: biblio-1412772

RESUMO

Introducción: las enfermedades pulmonares pueden generar hospitalizaciones, estancias prolongadas, complicaciones e inclusive la muerte. Estas enfermedades repercuten negativamente en la capacidad inspiratoria y en la calidad de vida. Por lo tanto, el presente artículo pretende analizar los efectos del Método JaPer sobre la capacidad inspiratoria de los pacientes hospitalizados. Material y métodos: ensayo clínico aleatorizado inicialmente con 653 pacientes hospitalizados que pasó a 587 distribuidos en 2 grupos (Grupo experimental-GE: Método JaPer vs Grupo control-GC: uso convencional de inspirómetro volumétrico). Se determinó la capacidad inspiratoria máxima, caminata de los 6 minutos, antropometría y un cuestionario creado por los autores. Se aplicó un programa de entrenamiento de 2 semanas de 3 sesiones por día. Al GE se le aplicó el Método Japer con protocolo estandarizado para hacer ejercicios entre el 50 y el 80 % de la capacidad inspiratoria máxima del paciente y a los pacientes del GC se les realizó incentivo inspiratorio a inspiración máxima. Resultados: 587 pacientes (F:300 vs M:287) con edad promedio de 53.61±14.24 años, entre los cuales el 9.88 % tenía bajo peso, 17.89 % peso normal y el 27.26 % y 44.97 % sobrepeso y obesidad, respectivamente. Todos los participantes realizaron una caminata de 6 minutos para determinar los metros recorridos (GE: 387.70±47.59 vs GC: 371.30±49.10), velocidad (GE: 64.62±7.93 vs GC: 61.88±8.18) y el Vo2 estimado (GE: 9.96±0.79 vs GC: 9.69±0.82). Todas las variables y la capacidad inspiratoria máxima (GE: 1708.54±707.84 vs GC: 1448.83±692.79) determinaron pre y post entrenamiento. Conclusiones: el Método JaPer obtuvó mejores resultados en todas las variables evaluadas con diferencia significativa (p= <0.05) frente al grupo control, resaltando que la capacidad inspiratoria máxima aumentó en ambos grupos (GE:44 % vs GC:28 %; p= <0.05).


Introduction: Pulmonary diseases can generate hospitalizations, prolonged stays, complications and even death. These diseases have a negative impact on inspiratory capacity and quality of life. Therefore, this paper tries to analyze the effects of the JaPer method on the inspiratory capacity of hospitalized patients. Materials and methods: Randomized clinical trial initially with 653 patients, which went on to 587 hospitalized patients distributed in 2 groups (Experimental group: JaPer Method vs. Control group: Conventional use of volumetric inspirometer). Maximum inspiratory capacity, 6-minute walk, anthropometry, and a questionnaire created by the authors were determined. A 2-week training program of 3 sessions per day was applied. The GE applied the Japer Method with a standardized protocol to exercise between 50 and 80% of the patient's maximum inspiratory capacity, and the CG underwent inspiratory incentive at maximum inspiration. Results: 587 patients (F:300 vs M:287) with a mean age of 53.61±14.24 years and 9.88% of the population were underweight, 17.89% normal weight and 27.26% and 44.97% overweight and obese, respectively. All participants performed a 6-minute walk to determine meters traveled (GE: 387.70±47.59 vs CG: 371.30±49.10), speed (GE: 64.62±7.93 vs CG: 61.88±8.18) and estimated VO2 (GE: 9.96 ±0.79 vs CG: 9.69±0.82). All variables and maximal inspiratory capacity (GE: 1708.54±707.84 vs CG: 1448.83±692.79) were determined before and after training. Conclusions: The JaPer method obtained better results in all the variables evaluated with a significant difference (p=<0.05) compared to the control group. Highlighting that the maximum inspiratory capacity increased in both groups (GE:44% vs CG:28%; p=<0.05).


Assuntos
Humanos , Exercício Físico , Capacidade Inspiratória , Pneumopatias , Antropometria , Caminhada , Medidores de Velocidade
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