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1.
J Refract Surg ; 39(3): 150-157, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36892241

RESUMO

PURPOSE: To evaluate refractive and visual outcomes at different distances after implantation of an isofocal optic design intraocular lens (IOL) following cataract surgery. METHODS: This multicentric, retrospective/prospective, open-label, observational study considered 183 eyes of 109 patients who were implanted with the ISOPURE 123 (PhysIOL) IOL. The main outcome measures were refractive error and monocular and binocular uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected intermediate visual acuity (UIVA), and distance-corrected intermediate visual acuity (DCIVA) at 66 and 80 cm, uncorrected near visual acuity (UNVA), and distance-corrected near visual acuity (DCNVA) at 40 cm. Binocular visual acuity at different vergences (defocus curve) was also measured. Patients were evaluated at least 120 days postoperatively. RESULTS: A total of 95.7% of the eyes were within ±1.00 diopter (D) and 73.2% of the eyes were within ±0.50 D; the mean postoperative spherical equivalent was -0.12 ± 0.42 D. There were 90.54% and 98.57% of patients presenting a cumulative binocular UDVA and CDVA value of 20/25 or better, respectively; 80.65% and 50.0% of patients presented a binocular DCIVA value of 20/25 or better at 80 and 66 cm, respectively; and 41.94% of patients presented a binocular DCNVA value of 20/40 or better. The through-focus curve showed good visual acuity at far and intermediate distances with a depth of focus value of 1.50 D. No adverse events were reported. CONCLUSIONS: The current study shows that this isofocal optic design IOL provides excellent visual performance for far vision and functional intermediate vision with an extended range of vision. This lens is an effective option for providing functional intermediate vision and correcting aphakia. [J Refract Surg. 2023;39(3):150-157.].


Assuntos
Lentes Intraoculares , Facoemulsificação , Humanos , Implante de Lente Intraocular , Pseudofacia , Estudos Prospectivos , Estudos Retrospectivos , Visão Binocular , Refração Ocular , Desenho de Prótese
2.
Adv Sci (Weinh) ; 8(11): e2100067, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34105269

RESUMO

Spraying of agrochemicals (pesticides, fertilizers) causes environmental pollution on a million-ton scale. A sustainable alternative is target-specific, on-demand drug delivery by polymeric nanocarriers. Trunk injections of aqueous nanocarrier dispersions can overcome the biological size barriers of roots and leaves and allow distributing the nanocarriers through the plant. To date, the fate of polymeric nanocarriers inside a plant is widely unknown. Here, the in planta conditions in grapevine plants are simulated and the colloidal stability of a systematic series of nanocarriers composed of polystyrene (well-defined model) and biodegradable lignin and polylactic-co-glycolic acid by a combination of different techniques is studied. Despite the adsorption of carbohydrates and other biomolecules onto the nanocarriers' surface, they remain colloidally stable after incubation in biological fluids (wood sap), suggesting a potential transport via the xylem. The transport is tracked by fluorine- and ruthenium-labeled nanocarriers inside of grapevines by 19 F-magnetic resonance imaging or induced coupled plasma - optical emission spectroscopy. Both methods show that the nanocarriers are transported inside of the plant and proved to be powerful tools to localize nanomaterials in plants. This study provides essential information to design nanocarriers for agrochemical delivery in plants to sustainable crop protection.


Assuntos
Agroquímicos/farmacologia , Proteção de Cultivos , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Agroquímicos/química , Coloides/química , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Fertilizantes/efeitos adversos , Humanos , Lignina , Nanoestruturas , Praguicidas/efeitos adversos , Praguicidas/química , Plantas/efeitos dos fármacos , Polímeros/química , Polímeros/farmacologia
3.
J Colloid Interface Sci ; 601: 678-688, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34091315

RESUMO

The current spraying of agrochemicals is unselective and ineffective, consuming a high amount of fungicides, which endangers the environment and human health. Cellulose-based nanocarriers (NCs) are a promising tool in sustainable agriculture and suitable vehicles for stimuli-responsive release of agrochemicals to target cellulase-segregating fungi, which cause severe plant diseases such as Apple Canker. Herein, cellulose was modified with undec-10-enoic acid to a hydrophobic and cross-linkable derivative, from which NCs were prepared via thiol-ene addition in miniemulsion. During the crosslinking reaction, the NCs were loaded in situ with hydrophobic fungicides, Captan and Pyraclostrobin. NCs with average sizes ranging from 200 to 300 nm and an agrochemical-load of 20 wt% were obtained. Cellulose-degrading fungi, e.g. Neonectria. ditissima which is responsible for Apple Canker, lead to the release of fungicides from the aqueous NC dispersions suppressing fungal growth. In contrast, the non-cellulase segregating fungi, e.g. Cylindrocladium buxicola, do not degrade the agrochemical-loaded NCs. This selective action against Apple Canker fungi, N. ditissima, proves the efficacy of NC-mediated drug delivery triggered by degradation in the exclusive presence of cellulolytic fungi. Cellulose NCs represent a sustainable alternative to the current unselective spraying of agrochemicals that treats many crop diseases ineffectively.


Assuntos
Agroquímicos , Hypocreales , Celulose , Humanos , Doenças das Plantas
4.
Eur Radiol ; 31(12): 9221-9231, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34076743

RESUMO

OBJECTIVES: To determine the diagnostic accuracy of dual-energy CT (DECT) virtual noncalcium (VNCa) reconstructions for assessing thoracic disk herniation compared to standard grayscale CT. METHODS: In this retrospective study, 87 patients (1131 intervertebral disks; mean age, 66 years; 47 women) who underwent third-generation dual-source DECT and 3.0-T MRI within 3 weeks between November 2016 and April 2020 were included. Five blinded radiologists analyzed standard DECT and color-coded VNCa images after a time interval of 8 weeks for the presence and degree of thoracic disk herniation and spinal nerve root impingement. Consensus reading of independently evaluated MRI series served as the reference standard, assessed by two separate experienced readers. Additionally, image ratings were carried out by using 5-point Likert scales. RESULTS: MRI revealed a total of 133 herniated thoracic disks. Color-coded VNCa images yielded higher overall sensitivity (624/665 [94%; 95% CI, 0.89-0.96] vs 485/665 [73%; 95% CI, 0.67-0.80]), specificity (4775/4990 [96%; 95% CI, 0.90-0.98] vs 4066/4990 [82%; 95% CI, 0.79-0.84]), and accuracy (5399/5655 [96%; 95% CI, 0.93-0.98] vs 4551/5655 [81%; 95% CI, 0.74-0.86]) for the assessment of thoracic disk herniation compared to standard CT (all p < .001). Interrater agreement was excellent for VNCa and fair for standard CT (ϰ = 0.82 vs 0.37; p < .001). In addition, VNCa imaging achieved higher scores regarding diagnostic confidence, image quality, and noise compared to standard CT (all p < .001). CONCLUSIONS: Color-coded VNCa imaging yielded substantially higher diagnostic accuracy and confidence for assessing thoracic disk herniation compared to standard CT. KEY POINTS: • Color-coded VNCa reconstructions derived from third-generation dual-source dual-energy CT yielded significantly higher diagnostic accuracy for the assessment of thoracic disk herniation and spinal nerve root impingement compared to standard grayscale CT. • VNCa imaging provided higher diagnostic confidence and image quality at lower noise levels compared to standard grayscale CT. • Color-coded VNCa images may potentially serve as a viable imaging alternative to MRI under circumstances where MRI is unavailable or contraindicated.


Assuntos
Imagem Radiográfica a Partir de Emissão de Duplo Fóton , Tomografia Computadorizada por Raios X , Idoso , Medula Óssea , Edema , Feminino , Humanos , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
ACS Sustain Chem Eng ; 8(50): 18468-18475, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33381356

RESUMO

Lignin is a promising feedstock in sustainable formulations for agrochemicals not only because of its biodegradability but also because the biopolymer occurs naturally in the cell wall of plants and therefore is renewable and abundant. We used different lignin sulfonates to prepare stable aqueous dispersions of lignin nanocarriers loaded with agrochemicals by interfacial cross-linking in a direct miniemulsion. Despite the differences in structure and functionality, different lignin sulfonates were successfully methacrylated and degrees of methacrylation (>70%) were achieved. The resulting methacrylated lignin sulfonates were water-soluble and exhibited interfacial activity; they were used as reactive surfactants to stabilize oil droplets (cyclohexane or olive or rapeseed oil) loaded with a dithiol cross-linker [EDBET, 2,2'-(ethylenedioxy)bis(ethylthiol)] and a hydrophobic cargo (the fluorescent dye 1,3,5,7-tetramethyl-8-phenyl-4,4-difluoroboradiazaindacene or the commercial fungicides prothioconazole and pyraclostrobin). After the addition of a water-soluble base, the thia-Michael addition was initiated at the droplet interface and produced lignin sulfonate nanocarriers with a core-shell structure within oily core and a cross-linked shell. Nanocarriers with diameters of ca. 200-300 nm were prepared; encapsulation efficiencies between 65 and 90% were achieved depending on the cargo. When the amount of the cross-linker was varied, the resulting lignin nanocarriers allowed a controlled release of loaded cargo by diffusion over a period of several days. The strategy proves the potential of lignin sulfonates as a feedstock for delivery systems for advanced plant protection.

6.
Biopolymers ; 111(12): e23413, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33306838

RESUMO

The delivery of agrochemicals is typically achieved by the spraying of fossil-based polymer dispersions, which might accumulate in the soil and increase microplastic pollution. A potentially sustainable alternative is the use of biodegradable nano- or micro-formulations based on biopolymers, which can be degraded selectively by fungal enzymes to release encapsulated agrochemicals. To date, no hemicellulose nanocarriers for drug delivery in plants have been reported. Xylan is a renewable and abundant feedstock occurring naturally in high amounts in hemicellulose - a major component of the plant cell wall. Herein, xylan from corncobs was used to produce the first fungicide-loaded xylan-based nanocarriers by interfacial polyaddition in an inverse miniemulsion using toluene diisocyanate (TDI) as a crosslinking agent. The nanocarriers were redispersed in water and the aqueous dispersions were proven to be active in vitro against several pathogenic fungi, which are responsible for fungal plant diseases in horticulture or agriculture. Besides, empty xylan-based nanocarriers stimulated the growth of fungal mycelium, which indicated the degradation of xylan in the presence of the fungi, and underlined the degradation as a trigger to release a loaded agrochemical. This first example of crosslinked xylan-based nanocarriers expands the library of biodegradable and biobased nanocarriers for agrochemical release and might play a crucial role for future formulations in plant protection.


Assuntos
Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Fungos/efeitos dos fármacos , Fungicidas Industriais/química , Nanopartículas/química , Xilanos/química , Biopolímeros/química , Fungos/crescimento & desenvolvimento , Fungicidas Industriais/metabolismo
7.
Biomacromolecules ; 21(7): 2755-2763, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32543851

RESUMO

Lignin-based nano- and microcarriers are a promising biodegradable drug delivery platform inside of plants. Many wood-decaying fungi are capable of degrading the wood component lignin by segregated lignases. These fungi are responsible for severe financial damage in agriculture, and many of these plant diseases cannot be treated today. However, enzymatic degradation is also an attractive handle to achieve a controlled release of drugs from artificial lignin vehicles. Herein, chemically cross-linked lignin nanocarriers (NCs) were prepared by aza-Michael addition in miniemulsion, followed by solvent evaporation. The cross-linking of lignin was achieved with the bio-based amines (spermine and spermidine). Several fungicides-namely, azoxystrobin, pyraclostrobin, tebuconazole, and boscalid-were encapsulated in situ during the miniemulsion polymerization, demonstrating the versatility of the method. Lignin NCs with diameters of 200-300 nm (determined by dynamic light scattering) were obtained, with high encapsulation efficiencies (70-99%, depending on the drug solubility). Lignin NCs successfully inhibited the growth of Phaeomoniella chlamydospora and Phaeoacremonium minimum, which are lignase-producing fungi associated with the worldwide occurring fungal grapevine trunk disease Esca. In planta studies proved their efficiency for at least 4 years after a single injection into Vitis vinifera ("Portugieser") plants on a test vineyard in Germany. The lignin NCs are of high interest as biodegradable delivery vehicles to be applied by trunk injection against the devastating fungal disease Esca but might also be promising against other fungal plant diseases.


Assuntos
Fungicidas Industriais , Preparações Farmacêuticas , Ascomicetos , Lignina
8.
Adv Sci (Weinh) ; 6(15): 1802315, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31406660

RESUMO

Nanocarrier (NC)-mediated drug delivery is widely researched in medicine but to date has not been used in agriculture. The first curative NC-based treatment of the worldwide occurring grapevine trunk disease Esca, with more than 2 billion infected plants causing a loss yearly of $1.5 billion, is presented. To date, only repetitive spraying of fungicides is used to reduce chances of infection. This long-term treatment against Esca uses minimal amounts of fungicide encapsulated in biobased and biodegradable lignin NCs. A single trunk injection of <10 mg fungicide results in curing of an infected plant. Only upon Esca infection, ligninolytic enzymes, secreted by the Esca-associated fungi, degrade the lignin NC to release the fungicide. The specific antifungal activity is confirmed in vitro and in planta (in Vitis vinifera L. cv. 'Portugieser'). All treated plants prove to exhibit significantly fewer symptoms several weeks after treatment, and their condition is monitored for 5 years (2014-2018), proving a long-term curative effect of this NC treatment. This study proves the efficacy of this NC-mediated drug delivery for agriculture, using a minimum amount of fungicides. It is believed that this concept can be extended to other plant diseases worldwide to reduce extensive spraying of agrochemicals.

9.
Chem Commun (Camb) ; 55(13): 1947-1950, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30681089

RESUMO

Self-assembled hydrogels based on the industrially-relevant 1,3:2,4-dibenzylidene sorbitol framework functionalised with reactive acyl hydrazide (DBS-CONHNH2) peripheral groups react with aldehydes without disrupting the nanoscale gel network, adapting gel performance, and dynamically selecting specific aldehyde components from complex mixtures.

10.
ACS Biomater Sci Eng ; 3(10): 2375-2383, 2017 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33445295

RESUMO

Lignin is an abundant biopolymer that is mainly burned for energy production today. However, using it as a polyfunctional macromolecular building block would be desirable. Herein, Kraft lignin was modified through esterification of its hydroxyl groups with methacrylic anhydride. Then lignin nanocarriers with different morphologies (solid nanoparticles, core-shell structures, porous nanoparticles) were produced by a combination of miniemulsion polymerization and a solvent evaporation process. A UV-active cargo is used as a drug model to investigate the release behavior of the lignin nanocarriers depending on their morphology. To prove the enzymatic response of the lignin nanocarriers, we tested the enzyme laccase as a trigger to release the encapsulated cargo. Furthermore, porous lignin nanoparticles with high surface area were produced by carbonization. The carbon material has a high potential as an adsorbent, which was studied by adsorption tests with methylene blue. These biodegradable nanocarriers based on the polyfunctional bioresource lignin may find useful application as novel drug delivery vehicle in agriculture or as carbon materials for water purification.

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