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The objective of this work was to prepare and characterize liposomes containing co-encapsulated ascorbic acid (AA) and ascorbyl palmitate (AP), as well as to evaluate their stability, cytotoxicity, antioxidant, and antimicrobial activity. Through the pre-formulation studies, it was possible to improve the formulation, as leaving it more stable and with a greater antioxidant activity, resulting in a formulation designated LIP-AAP, with 161 nm vesicle size, 0.215 polydispersity index, -31.7 mV zeta potential, and pH of 3.34. Encapsulation efficiencies were 37% for AA and 79% for AP, and the content was 1 mg/mL for each compound. The optimized liposomes demonstrated stability under refrigeration for 60 days, significant antioxidant activity (31.4 µMol of TE/mL), and non-toxicity, but no antimicrobial effects against bacteria and fungi were observed. These findings confirm that the co-encapsulated liposomes are potent, stable antioxidants that maintain their physical and chemical properties under optimal storage conditions.
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The initial free expansion of the embryo within a seed is at some point inhibited by its contact with the testa, resulting in its formation of folds and borders. Although less obvious, mechanical forces appear to trigger and accelerate seed maturation. However, the mechanistic basis for this effect remains unclear. Manipulation of the mechanical constraints affecting either the in vivo or in vitro growth of oilseed rape embryos was combined with analytical approaches, including magnetic resonance imaging and computer graphic reconstruction, immunolabelling, flow cytometry, transcriptomic, proteomic, lipidomic and metabolomic profiling. Our data implied that, in vivo, the imposition of mechanical restraints impeded the expansion of testa and endosperm, resulting in the embryo's deformation. An acceleration in embryonic development was implied by the cessation of cell proliferation and the stimulation of lipid and protein storage, characteristic of embryo maturation. The underlying molecular signature included elements of cell cycle control, reactive oxygen species metabolism and transcriptional reprogramming, along with allosteric control of glycolytic flux. Constricting the space allowed for the expansion of in vitro grown embryos induced a similar response. The conclusion is that the imposition of mechanical constraints over the growth of the developing oilseed rape embryo provides an important trigger for its maturation.
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Adventitious root (AR) formation is one of the most important developmental processes in vegetative propagation. Although genotypic differences in rose rooting ability are well known, the causal factors are not well understood. The rooting of two contrasting genotypes, 'Herzogin Friederike' and 'Mariatheresia', was compared following a multiscale approach. Using magnetic resonance imaging, we non-invasively monitored the inner structure of stem cuttings during initiation and progression of AR formation for the first time. Spatially resolved Fourier-transform infrared spectroscopy characterized the chemical composition of the tissues involved in AR formation. The results were validated through light microscopy and complemented by immunolabelling. The outcome demonstrated similarity of both genotypes in root primordia formation, which did not result in root protrusion through the shoot cortex in the difficult-to-root genotype 'Mariatheresia'. The biochemical composition of the contrasting genotypes highlighted main differences in cell wall-associated components. Further spectroscopic analysis of 15 contrasting rose genotypes confirmed the biochemical differences between easy- and difficult-to-root groups. Collectively, our data indicate that it is not the lack of root primordia limiting AR formation in these rose genotypes, but the firmness of the outer stem tissue and/or cell wall modifications that pose a mechanical barrier and prevent root extension and protrusion.
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Genótipo , Imageamento por Ressonância Magnética , Raízes de Plantas , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/genética , Espectroscopia de Infravermelho com Transformada de Fourier , FenótipoRESUMO
Imaging has long supported our ability to understand the inner life of plants, their development, and response to a dynamic environment. While optical microscopy remains the core tool for imaging, a suite of novel technologies is now beginning to make a significant contribution to visualize plant metabolism. The purpose of this review was to provide the scientific community with an overview of current imaging methods, which rely variously on either nuclear magnetic resonance (NMR), mass spectrometry (MS) or infrared (IR) spectroscopy, and to present some examples of their application in order to illustrate their utility. In addition to providing a description of the basic principles underlying these technologies, the review discusses their various advantages and limitations, reveals the current state of the art, and suggests their potential application to experimental practice. Finally, a view is presented as to how the technologies will likely develop, how these developments may encourage the formulation of novel experimental strategies, and how the enormous potential of these technologies can contribute to progress in plant science.
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Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de MassasRESUMO
Even though Sugars Will Eventually be Exported Transporters (SWEETs) have been found in every sequenced plant genome, a comprehensive understanding of their functionality is lacking. In this study, we focused on the SWEET family of barley (Hordeum vulgare). A radiotracer assay revealed that expressing HvSWEET11b in African clawed frog (Xenopus laevis) oocytes facilitated the bidirectional transfer of not only just sucrose and glucose, but also cytokinin. Barley plants harboring a loss-of-function mutation of HvSWEET11b could not set viable grains, while the distribution of sucrose and cytokinin was altered in developing grains of plants in which the gene was knocked down. Sucrose allocation within transgenic grains was disrupted, which is consistent with the changes to the cytokinin gradient across grains, as visualized by magnetic resonance imaging and Fourier transform infrared spectroscopy microimaging. Decreasing HvSWEET11b expression in developing grains reduced overall grain size, sink strength, the number of endopolyploid endosperm cells, and the contents of starch and protein. The control exerted by HvSWEET11b over sugars and cytokinins likely predetermines their synergy, resulting in adjustments to the grain's biochemistry and transcriptome.
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Citocininas , Hordeum , Citocininas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Hordeum/genética , Hordeum/metabolismo , Açúcares/metabolismo , Sacarose/metabolismoRESUMO
Maize (Zea mays) kernels are the largest cereal grains, and their endosperm is severely oxygen deficient during grain fill. The causes, dynamics, and mechanisms of acclimation to hypoxia are minimally understood. Here, we demonstrate that hypoxia develops in the small, growing endosperm, but not the nucellus, and becomes the standard state, regardless of diverse structural and genetic perturbations in modern maize (B73, popcorn, sweet corn), mutants (sweet4c, glossy6, waxy), and non-domesticated wild relatives (teosintes and Tripsacum species). We also uncovered an interconnected void space at the chalazal pericarp, providing superior oxygen supply to the placental tissues and basal endosperm transfer layer. Modeling indicated a very high diffusion resistance inside the endosperm, which, together with internal oxygen consumption, could generate steep oxygen gradients at the endosperm surface. Manipulation of oxygen supply induced reciprocal shifts in gene expression implicated in controlling mitochondrial functions (23.6 kDa Heat-Shock Protein, Voltage-Dependent Anion Channel 2) and multiple signaling pathways (core hypoxia genes, cyclic nucleotide metabolism, ethylene synthesis). Metabolite profiling revealed oxygen-dependent shifts in mitochondrial pathways, ascorbate metabolism, starch synthesis, and auxin degradation. Long-term elevated oxygen supply enhanced the rate of kernel development. Altogether, evidence here supports a mechanistic framework for the establishment of and acclimation to hypoxia in the maize endosperm.
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Amido , Zea mays , Gravidez , Feminino , Humanos , Zea mays/metabolismo , Amido/metabolismo , Placenta/metabolismo , Endosperma/metabolismo , Oxigênio/metabolismo , Hipóxia/metabolismoRESUMO
Haemonchus contortus is a highly pathogenic and prevalent helminth that causes many deaths in sheep herds. Anthelmintics are usually employed to overcome this issue; however, they do not guarantee immediate and lasting efficacy because of the occurrence of drug-resistant parasites. Among substances that are used in scientific studies for parasitic control, essential oils are known to have different pharmacological properties. However, they demonstrate instability owing to several factors, and therefore, nanoemulsification is considered an alternative to control the instability and degradability of these compounds. The objective of this study was to evaluate the cytotoxicity of nanoemulsions containing essential oil of Eucalyptus globulus against the blood of healthy sheep and to verify their activity against the parasite H. contortus in sheep. The results presented adequate nanotechnological characteristics (diameter 72 nm, PDI 0.2, zeta -11 mV, and acidic pH) and adequate morphology. Further, the corona effect and cytotoxic profiles of the free oil and nanoemulsion against blood cells from healthy sheep were evaluated. The tests results did not present a toxicity profile. For evaluating efficacy, we observed an important anthelmintic action of the nanoemulsion containing oil in comparison to the free oil; the results demonstrate a potential role of the nanoemulsion in the inhibition of egg hatchability and the development of larvae L1 to L3 (infective stage). Based on these results, we developed an important and potential anthelmintic alternative for the control of the parasite H. contortus.
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Anti-Helmínticos , Hemoncose , Haemonchus , Óleos Voláteis , Doenças dos Ovinos , Animais , Anti-Helmínticos/uso terapêutico , Anti-Helmínticos/toxicidade , Óleo de Eucalipto/farmacologia , Hemoncose/tratamento farmacológico , Hemoncose/parasitologia , Hemoncose/veterinária , Larva , Óleos Voláteis/química , Óleos Voláteis/toxicidade , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologiaRESUMO
Ferulic acid (FA) is a phenolic compound that has antioxidant, anti-inflammatory and anticarcinogenic properties besides presenting cytoprotective activity. It has limited oral bioavailability what is a challenge to its therapeutic application. In this way, this investigation aimed to develop FA-loaded nanocapsule suspensions (NC-FA) prepared with ethylcellulose and evaluate their in vitro release profile, mucoadhesion and irritation potential; scavenging capacity, cytotoxicity, cytoprotection and genoprotection against hydrogen peroxide-induced damage in hMNC (human Mononucleated Cells) culture. The nanocapsules presented physicochemical characteristics compatible with colloidal systems (NC-FA: 112 ± 3 nm; NC-B (without FA): 107 ± 3 nm; PdI < 0.2; Span<2.0 and negative zeta potential). In addition, the nanoparticulate system promoted the FA controlled release, increasing the half-life twice through the in vitro dialysis method. NC-FA and NC-B were able to interact with mucin, which is an indicative of mucoadhesive properties and the association of FA with nanocapsules showed decreased irritation by HET-CAM method. Besides, the NC-FA did not present cytotoxicity in hMNC and improved the ATBS radical scavenging capacity. Besides, it prevented, treated and reversed oxidative conditions in a H2O2-induced model in hMNC. Thus, this nanocarrier formulation is promising to perform more preclinical investigations focusing on diseases involving oxidative mechanisms.
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Antioxidantes/administração & dosagem , Ácidos Cumáricos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Nanocápsulas/química , Animais , Antioxidantes/farmacocinética , Antioxidantes/farmacologia , Células Cultivadas , Celulose/análogos & derivados , Embrião de Galinha , Ácidos Cumáricos/farmacocinética , Ácidos Cumáricos/farmacologia , Humanos , Peróxido de Hidrogênio/toxicidade , Irritantes , Linfócitos , Mucinas , Nanocápsulas/efeitos adversosRESUMO
The objective of this work was to produce and characterise nanoemulsions containing tucumã extract and to evaluate the performance of the nanostructure and the free compound regarding antitumor activity, cytotoxicity, and oxidative metabolism in NB4/APL cells. The nanoemulsions showed adequate physicochemical characteristics (average size approx. 200 nm, polydispersity index less than 0.3, negative zeta potential and acid pH) maintained stable up to 90 days of storage in refrigeration condition. The nanoformulations did not present protein corona formation. Blank nanoemulsion treatments showed moderate toxicity. Furthermore, the nanoemulsion loaded with extract showed better antileukemic results than the free extract. However, nanoemulsions can be promising carriers of natural compounds, emphasising their biological properties and constituting alternatives in treating diseases.
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Arecaceae , Nanoestruturas , Antioxidantes/química , Emulsões/química , Nanoestruturas/químicaRESUMO
The aim of this study was to evaluate the toxicity of tucumã oil nanocapsules from the Amazon region in silver catfish, Rhamdia quelen. Fish were exposed to water treated with different concentrations of tucumã nanocapsules, white, solubilized oil and surfactant vehicles. After three days of exposure, fish were euthanized and liver, gills and brain removed for analysis of the dichlorofluorescein, nitric oxide and PicoGreen® assays. Plasma was collected for assay of hepatic transaminases. The nanocapsules had a diameter of 221 ± 1.27 nm, confirmed by atomic force microscopy. The oil nanocapsules were not toxic to this species of fish, but white nanocapsules and surfactant increased the levels of reactive oxygen species. Thus, nanocapsules are promising for the transport of tucumã oil. In view of the anti-inflammatory properties of this oil, it is possible to envisage its application in skin diseases for example, since they present essentially inflammatory conditions.HighlightsThe most abundant carotenoid in tucumã oil was all-trans-beta-carotene.Nanocapsules are good carriers for tucumã oil.Tucumã oil nanocapsules does nothas toxicity effect in catfish.
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Peixes-Gato , Nanocápsulas , Animais , Brânquias , Fígado , Modelos TeóricosRESUMO
Abstract The objective of this study was to evaluate the influence of vitamin C (VC) on the stability of stored liposomes under different climatic conditions. Liposomal formulations containing 1 mg/mL of VC (LIP-VC) and blank formulations (LIP-B) were prepared by the reverse-phase evaporation method. After preparation, they were characterized according to their refractive index, average vesicle diameter, polydispersity index (PDI), zeta potential, pH, content, encapsulation efficiency (EE%), morphology, stability and antioxidant activity. For stability, LIP-VC and LIP-B were stored in different climatic conditions (4 °C, 25 °C and 40 °C) for 30 days. The LIP-VC presented 1.3365 refractive index, 161 nm of mean diameter, 0.231 PDI, -7.3 mV zeta potential, 3.2 pH, 19.4% EE%, spherical morphology, 1 mg/mL of VC content, and antioxidant activity of 12 and 11.4 μmol of TE/mL for the radical DPPH and ABTS+, respectively. During stability, the LIP-B stored in 40 °C showed an instability in the parameters: PDI, vesicle size and zeta potential after 15 days, while the LIP-VC remained stable in its size and PDI for 30 days. After that, it is shown that VC can be used as an antioxidant and stabilizer in liposomes to increase the stability and shelf-life of vesicles.
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Cereal grains contribute substantially to the human diet. The maternal plant provides the carbohydrate and nitrogen sources deposited in the endosperm, but the basis for their spatial allocation during the grain filling process is obscure. Here, vacuolar processing enzymes have been shown to both mediate programmed cell death (PCD) in the maternal tissues of a barley grain and influence the delivery of assimilate to the endosperm. The proposed centrality of PCD has implications for cereal crop improvement.
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Apoptose , Cisteína Endopeptidases/metabolismo , Grão Comestível/crescimento & desenvolvimento , Endosperma/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Hordeum/fisiologia , Grão Comestível/enzimologia , Grão Comestível/fisiologia , Hordeum/enzimologia , Hordeum/crescimento & desenvolvimentoRESUMO
The bioinsecticides, like essential oils, are a promising alternative in pest control. However, these oils have some limitations, such as instability and low solubility. These limitations can be circumvented through nanotechnology, with the nanoemulsification of these compounds. Therefore, the objective of this study was to prepare, characterize and explore the insecticidal activity against adult flies of nanoemulsions containing essential oil of lemongrass or eucalyptus. The nanoemulsions were prepared by the high-energy method and presented droplet size smaller than 125 nm, with polydispersity index of 0.2, pH acid and spherical morphology. The insecticidal activity was evaluated by the Topical Application Method and Exposure Impregnated Paper Exposure, where it was possible to demonstrate a potential insecticidal effect of lemongrass oil in the concentrations of 10, 30 and 50 µL/mL against Musca domestica and Lucilia cuprina and the potentiation of this effect when nanoemulsified this oil against L. cuprina.
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Cymbopogon , Eucalyptus , Moscas Domésticas , Inseticidas , Óleos Voláteis , Animais , Inseticidas/farmacologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologiaRESUMO
The main objective of this study was to evaluate whether the addition of curcumin-loaded nanocapsules (prepared and characterized) in the diets of dairy sheep improved milk quality. The nanocapsules were prepared using two polymers: poly-ε-caprolactone (PCL) and Eudragit L-100. The nanocapsules contained 0.25 mg/ml (Nano-Eudragit L-100) and 2 mg/ml (Nano-PCL) of curcumin. Dairy sheep were divided into four groups: A (control), B (30 mg free curcumin/kg concentrate), C (3 mg Nano-PCL/kg concentrate), and D (3 mg Nano-Eudragit/kg concentrate). We observed that the number of total leukocytes and serum globulin levels were lower in Group D than in the control (Group A) (p < 0.05). Antioxidant capacity against peroxyl radicals (ACAP) and catalase enzymes was elevated in Group D, with consequently reduced lipid peroxidation (LPO; p < 0.05). In milk, there were no differences in production and composition between groups during the experimental period (p > 0.05); however, ACAP increased and LPO decreased in milk. PRACTICAL APPLICATIONS: Curcumin is a functional molecule with potent antioxidant, anti-inflammatory, and antimicrobial actions, used frequently and with medical indications in human food. Free curcumin in sheep diets improves milk quality and increases its shelf life. This study showed that curcumin nanocapsules produced from the Eudragit L-100 polymer potentiated the anti-inflammatory and antioxidant actions of dairy sheep when used in the diet daily, at doses 10 times lower than that of free curcumin. These positive effects were reflected in higher total antioxidant capacity and lower lipid peroxidation in milk in sheep-fed curcumin-loaded Eudragit L-100 nanocapsules, generating desirable milk properties. In practice, the use of nanotechnology enhances the beneficial effects of curcumin in milk, possibly creating a nutraceutical food desirable to consumers.
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Antioxidantes/metabolismo , Curcumina/administração & dosagem , Leite/química , Ovinos/metabolismo , Ração Animal/análise , Animais , Curcumina/química , Suplementos Nutricionais/análise , Composição de Medicamentos , Feminino , Armazenamento de Alimentos , Peroxidação de Lipídeos , Leite/metabolismo , Nanocápsulas/administração & dosagem , Nanocápsulas/química , Ácidos Polimetacrílicos/químicaRESUMO
Hypericin is a molecule of high pharmaceutical importance that is synthesized and stored in dark glands (DGs) of St. John's Wort (Hypericum perforatum). Understanding which genes are involved in dark gland development and hypericin biosynthesis is important for the development of new Hypericum extracts that are highly demanded for medical applications. We identified two transcription factors whose expression is strictly synchronized with the differentiation of DGs. We correlated the content of hypericin, pseudohypericin, endocrocin, skyrin glycosides and several flavonoids with gene expression and DG development to obtain a revised model for hypericin biosynthesis. Here, we report for the first time genotypes which are polymorphic for the presence/total absence (G+/G-) of DGs in their placental tissues (PTs). DG development was characterized in PTs using several microscopy techniques. Fourier transform infrared microscopy was established as a novel method to precisely locate polyaromatic compounds, such as hypericin, in plant tissues. In addition, we obtained transcriptome and metabolome profiles of unprecedented resolution in Hypericum. This study addresses for the first time the development of dark glands and identifies genes that constitute strong building blocks for the further elucidation of hypericin synthesis, its manipulation in plants, its engineering in microbial systems and its applications in medical research.
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Hypericum/genética , Hypericum/metabolismo , Perileno/análogos & derivados , Antracenos , Flavonoides , Genes de Plantas , Metaboloma , Perileno/metabolismo , TranscriptomaRESUMO
Pseudomonas aeruginosa is a ubiquitous microorganism that commonly causes hospital-acquired infections, including pneumonia, bloodstream and urinary tract infections and it is well known for chronically colonising the respiratory tract of patients with cystic fibrosis, causing severe intermittent exacerbation of the condition. P. aeruginosa may appear in the free form cell but also grows in biofilm communities adhered to a surface. An alternative to conventional antimicrobial agents are nanoparticles that can act as carriers for antibiotics and other drugs. In this context, the study aimed to characterise and verify the anti-biofilm potential of GML Nanocapsules against P. aeruginosa. The nanocapsules showed a mean diameter of 190.7â¯nm, polydispersion index of 0.069, the zeta potential of -23.3â¯mV. The microdilution test showed a MIC of 62.5⯵g/mL to GML and 15.62⯵g/mL to GML Nanocapsules. The anti-biofilm experiments demonstrated the significant reduction of biomass, proteins, polysaccharide and viable P. aeruginosa in biofilm treated with GML Nanocapsules while the free GML did not cause an effect. The AFM images showed a decrease in a biofilm which received GML. The positive results suggest an alternative for the public health trouble related to infections associated with biofilm.
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Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Lauratos/farmacologia , Monoglicerídeos/farmacologia , Nanocápsulas , Pseudomonas aeruginosa/efeitos dos fármacos , Tensoativos/farmacologia , Portadores de Fármacos , Testes de Sensibilidade MicrobianaRESUMO
The present study developed and characterized microparticles formulations containing acyclovir and curcumin co-encapsulated in order to overcome the biopharmaceutical limitations and increase the antiviral effect of both drugs. The microparticles were prepared by a spray drying methodology following the ratio 1:3 (drug:polymer), which were made by hydroxypropylmethylcellulose (HPMC) and/or Eudragit® RS100 (EUD). The MP-1 formulation was composed of HPMC and EUD (1:1), MP-2 formulation was composed only of HPMC and MP-3 formulation was composed only of EUD. All formulations showed yielding around 50% and acceptable powder flowability. Drug content determination around 82.1-96.8% and 81.8-87% for acyclovir and curcumin, respectively. The microparticles had spherical shape, size within 11.5-15.3⯵m, unimodal distribution and no chemical interactions among the components of the formulations. Of particular importance, the polymeric composition considerably influenced on the release profile of the drugs. The in vitro release experiment demonstrated that the microencapsulation provided a sustained release of acyclovir as well as increased the solubility of curcumin. Besides, mathematical modeling indicated that the experimental fit biexponential equation. Importantly, drugs microencapsulation promoted superior antiviral effect against BoVH-1 virus in comparison to their free form, which could be attributed to the improvement in the aforementioned physicochemical parameters. Therefore, these formulations could be promising technological drug carriers for acyclovir and curcumin, which highlight the great offering a potential alternative treatment for viral herpes.
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Aciclovir , Antivirais , Curcumina , Portadores de Fármacos , Resinas Acrílicas/administração & dosagem , Resinas Acrílicas/química , Aciclovir/administração & dosagem , Aciclovir/química , Animais , Antivirais/administração & dosagem , Antivirais/química , Bovinos , Linhagem Celular , Curcumina/administração & dosagem , Curcumina/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Composição de Medicamentos , Liberação Controlada de Fármacos , Sinergismo Farmacológico , Herpesvirus Bovino 1/efeitos dos fármacos , Derivados da Hipromelose/administração & dosagem , Derivados da Hipromelose/químicaRESUMO
INTRODUCTION: The surface charge of nanoparticles, such as nanospheres (NS) and nanocapsules (NC), has been studied with the purpose of improving the in vivo performance of drugs. The aim of this study was to develop, characterize, and evaluate the in vitro antimalarial efficacy of NCP80 and NSP80 (polysorbate coated) or NCEUD and NSEUD (prepared with Eudragit RS 100) loading quinine (QN). METHODS: Formulations were prepared by the nanoprecipitation method, followed by wide physicochemical characterization. Antimalarial activity in Plasmodium berghei-infected mice and populational pharmacokinetics (PopPK) in rats were evaluated. RESULTS: The formulations showed a nanometric range (between 138 ± 3.8 to 201 ± 23.0 nm), zeta potential (mV) of -33.1 ± 0.7 (NCP80), -30.5 ± 1 (UNCP80), -25.5 ± 1 (NSP80), -20 ± 0.3 (UNSP80), 4.61 ± 1 (NCEUD), 14.1 ± 0.9 (UNCEUD), 2.86 ± 0.3 (NSEUD) and 2.84 ± 0.6 (UNSEUD), content close to 100%, and good QN protection against UVA light. There was a twofold increase in the penetration of QN into infected erythrocytes with NC compared to that with NS. There was a significant increase in t1/2 for all NC evaluated compared to that of Free-QN, due to changes in Vdss. PopPK analysis showed that NCP80 acted as a covariate to Q (intercompartmental clearance) and V2 (volume of distribution in the peripheral compartment). For NCEUD, V1 and Q were modified after QN nanoencapsulation. Regarding in vivo efficacy, NCEUD increased the survival of mice unlike Free-QN. CONCLUSION: Cationic nanocapsules modified the pharmacology of QN, presenting a potential alternative for malaria treatment.
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Antimaláricos/farmacocinética , Portadores de Fármacos/farmacocinética , Malária/tratamento farmacológico , Nanocápsulas/química , Quinina/farmacocinética , Resinas Acrílicas/química , Animais , Antimaláricos/química , Portadores de Fármacos/química , Eritrócitos/efeitos dos fármacos , Eritrócitos/parasitologia , Malária/mortalidade , Masculino , Camundongos , Nanosferas/química , Plasmodium berghei/efeitos dos fármacos , Plasmodium berghei/patogenicidade , Polissorbatos/química , Quinina/química , Ratos Wistar , Propriedades de SuperfícieRESUMO
This study evaluated the effect of different hydrofluoric acid (HF) concentrations on the bond strength between a lithium disilicate-based glass ceramic and a resin cement. Eighty ceramic-blocks (12×7×2 mm) of IPS e.Max CAD (Ivoclar Vivadent) were produced and randomly assigned to 8 groups, considering 2 study factors: HF concentration in 4 levels, i.e., 1% (HF1), 3% (HF3), 5% (HF5), and 10% (HF10), and storage in 2 levels, i.e., baseline (tests were performed 24 h after cementation), and aged (storage for 150 days + 12,000 thermal-cycles at 5°C and 55°C). Acid etching (20 s) was performed, followed by washing, drying, and silanization. Four resin cement cylinders (Ï= 0.96 mm) were built-up from starch matrices on each ceramic sample (n= 40). Additional ceramic samples were etched and analyzed for contact angle, micro-morphology, and roughness. In baseline condition (without aging), the HF3, HF5, and HF10 groups showed similar bond strength values (13.9 - 15.9 MPa), and HF1 (11.2 MPa) presented lower values than HF5, being that statistically different (p= 0.012). After aging, all the mean bond strengths statistically decreased, being that HF3, HF5, and HF10 (7.8 - 11 MPa) were similar and higher than HF1 (1.8 MPa) (p= 0.0001). For contact angle, HF3, HF5, and HF10 presented similar values (7.8 - 10.4°), lower than HF1 and CTRL groups. HF5 and HF10 presented rougher surfaces than other conditions. For better bond strength results, the tested ceramic may be etched by HF acid in concentrations of 3%, 5%, and 10%.
Assuntos
Condicionamento Ácido do Dente/métodos , Cerâmica/química , Colagem Dentária/métodos , Porcelana Dentária/química , Ácido Fluorídrico/química , Cimentos de Resina/química , Teste de Materiais , Microscopia de Força Atômica , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de SuperfícieRESUMO
Successful biotrophic plant pathogens can divert host nutrition toward infection sites. Here we describe how the protist Plasmodiophora brassicae establishes a long-term feeding relationship with its host by stimulating phloem differentiation and phloem-specific expression of sugar transporters within developing galls. Development of galls in infected Arabidopsis (Arabidopsis thaliana) plants is accompanied by stimulation of host BREVIS RADIX, COTYLEDON VASCULAR PATTERN, and OCTOPUS gene expression leading to an increase in phloem complexity. We characterized how the arrest of this developmental reprogramming influences both the host and the invading pathogen. Furthermore, we found that infection leads to phloem-specific accumulation of SUGARS WILL EVENTUALLY BE EXPORTED TRANSPORTERS11 and 12 facilitating local distribution of sugars toward the pathogen. Utilizing Fourier-transform infrared microspectroscopy to monitor spatial distribution of carbohydrates, we found that infection leads to the formation of a strong physiological sink at the site of infection. High resolution metabolic and structural imaging of sucrose distributions revealed that sweet11 sweet12 double mutants are impaired in sugar transport toward the pathogen, delaying disease progression. This work highlights the importance of precise regulation of sugar partitioning for plant-pathogen interactions and the dependence of P brassicae's performance on its capacity to induce a phloem sink at the feeding site.