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1.
PLoS Genet ; 19(5): e1010751, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37141297

RESUMO

Methyl salicylate is an important inter- and intra-plant signaling molecule, but is deemed undesirable by humans when it accumulates to high levels in ripe fruits. Balancing the tradeoff between consumer satisfaction and overall plant health is challenging as the mechanisms regulating volatile levels have not yet been fully elucidated. In this study, we investigated the accumulation of methyl salicylate in ripe fruits of tomatoes that belong to the red-fruited clade. We determine the genetic diversity and the interaction of four known loci controlling methyl salicylate levels in ripe fruits. In addition to Non-Smoky Glucosyl Transferase 1 (NSGT1), we uncovered extensive genome structural variation (SV) at the Methylesterase (MES) locus. This locus contains four tandemly duplicated Methylesterase genes and genome sequence investigations at the locus identified nine distinct haplotypes. Based on gene expression and results from biparental crosses, functional and non-functional haplotypes for MES were identified. The combination of the non-functional MES haplotype 2 and the non-functional NSGT1 haplotype IV or V in a GWAS panel showed high methyl salicylate levels in ripe fruits, particularly in accessions from Ecuador, demonstrating a strong interaction between these two loci and suggesting an ecological advantage. The genetic variation at the other two known loci, Salicylic Acid Methyl Transferase 1 (SAMT1) and tomato UDP Glycosyl Transferase 5 (SlUGT5), did not explain volatile variation in the red-fruited tomato germplasm, suggesting a minor role in methyl salicylate production in red-fruited tomato. Lastly, we found that most heirloom and modern tomato accessions carried a functional MES and a non-functional NSGT1 haplotype, ensuring acceptable levels of methyl salicylate in fruits. Yet, future selection of the functional NSGT1 allele could potentially improve flavor in the modern germplasm.


Assuntos
Solanum lycopersicum , Humanos , Solanum lycopersicum/genética , Salicilatos/análise , Salicilatos/química , Salicilatos/metabolismo , Glicosiltransferases , Equador , Frutas/genética
2.
Planta ; 252(6): 103, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33185761

RESUMO

MAIN CONCLUSION: Nicotiana tabacum overexpressing CrSAMT from Citrus reticulata increased production of MeSA, which works as an airborne signal in neighboring wild-type plants, inducing PR1 and increasing resistance to the pathogen Xylella fastidiosa. Xylella fastidiosa is one of the major threats to plant health worldwide, affecting yield in many crops. Despite many efforts, the development of highly productive resistant varieties has been challenging. In studying host plant resistance, the S-adenosyl-L-methionine: salicylic acid carboxyl methyltransferase gene (SAMT) from Citrus reticulata, a X. fastidiosa resistant species, was upregulated in response to pathogen infection. SAMT is involved with the catalysis and production of methyl salicylate (MeSA), an airborne signal responsible for triggering systemic acquired resistance. Here we used tobacco as a model system and generated transgenic plants overexpressing C. reticulata SAMT (CrSAMT). We performed an in silico structural characterization of CrSAMT and investigated its biotechnological potential in modulating the immune system in transgenic plants. The increase of MeSA production in transgenic lines was confirmed by gas chromatography (GC-MS). The transgenic lines showed upregulation of PR1, and their incubation with neighboring wild-type plants activated PR1 expression, indicating that MeSA worked as an airborne signal. In addition, transgenic plants showed significantly fewer symptoms when challenged with X. fastidiosa. Altogether, these data suggest that CrSAMT plays a role in host defense response and can be used in biotechnology approaches to confer resistance against X. fastidiosa.


Assuntos
Citrus , Expressão Gênica , Metiltransferases , Salicilatos , Xylella , Citrus/genética , Citrus/microbiologia , Metiltransferases/genética , Metiltransferases/metabolismo , Doenças das Plantas , Proteínas Recombinantes/genética , Salicilatos/química , Nicotiana/genética , Volatilização , Xylella/fisiologia
3.
Int J Biol Macromol ; 164: 2558-2568, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32805287

RESUMO

Transdermal patches for analgesic purposes are widely used, however, their occlusive characteristics can often cause allergic reactions, irritating contact dermatitis, and allergic contact dermatitis upon extended use. Chitosan is a natural positively charged bioadhesive polysaccharide with several biological properties, being promising templates for sustained and controlled topical or transdermal drug delivery. Methyl salicylate (MS) is a non-steroidal topical anti-inflammatory drug (NSAID). MS is a lipophilic oily drug commonly found in transdermal patches, being difficult to incorporate into hydrophilic formulations such as Chitosan-based films. Thus, MS is a good candidate to be encapsulated into nanoemulsions (NE). This work reports the formulation development, physical-chemical characterization, and in vitro drug release of NE-loaded Chitosan films formulated with MS, as a novel substitute for transdermal analgesic patches. MS was encapsulated into NE, which were prepared by ultrasonication and presented 29.3 nm ± 0.1 and PdI 0.167 ± 0.005. The incorporation of MS into NE prevented phase separation and provided a homogeneous physical blending formulation, as confirmed by FTIR, TGA. NE-loaded films provided high drug incorporation in the films 94.08% ± 6.63%), and a smaller crystallinity degree in comparison with physical mixture films, suggesting a plasticizing effect of nano-sized droplets. Besides, mean weight, thickness, and moisture content were increased in NE-loaded films in comparison with chitosan-based control films. In vitro drug release from NE-loaded films was significantly higher than for physical mixture films, following Weibull and Korsmeyer-Peppas release kinetics models. The results suggest that NE-loaded chitosan film can increase the drug loading capacity of oil drugs and successfully control in vitro release, constituting a novel approach for transdermal drug delivery of NSAIDs.


Assuntos
Quitosana/química , Membranas Artificiais , Salicilatos , Adesivo Transdérmico , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Emulsões , Humanos , Salicilatos/química , Salicilatos/farmacocinética
4.
Molecules ; 23(7)2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29973523

RESUMO

The antibacterial effects against Staphylococcus epidermidis of five silver carboxylate complexes with anti-inflammatory ligands were studied in order to analyze and compare them in terms of stability (in solution and after exposure to UV light), and their antibacterial and morphological differences. Four effects of the Ag-complexes were evidenced by transmission electronic microscopy (TEM) and scanning electronic microscopy (SEM): DNA condensation, membrane disruption, shedding of cytoplasmic material and silver compound microcrystal penetration of bacteria. 5-Chlorosalicylic acid (5Cl) and sodium 4-aminosalicylate (4A) were the most effective ligands for synthesizing silver complexes with high levels of antibacterial activity. However, Ag-5Cl was the most stable against exposure UV light (365 nm). Cytotoxic effects were tested against two kinds of eukaryotic cells: murine fibroblast cells (T10 1/2) and human epithelial ovarian cancer cells (A2780). The main objective was to identify changes in their antibacterial properties associated with potential decomposition and the implications for clinical applications.


Assuntos
Antibacterianos/síntese química , Complexos de Coordenação/síntese química , Prata/química , Staphylococcus epidermidis/efeitos dos fármacos , Ácidos Aminossalicílicos/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Linhagem Celular , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Estabilidade de Medicamentos , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Salicilatos/química
5.
Braz Dent J ; 29(2): 195-201, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29898068

RESUMO

This study investigated the bond strength of two experimental root canal sealers based on MTA and butyl ethylene glycol disalicylate: MTAe and MTAe-HA. The reference materials used for comparison were AH Plus and MTA Fillapex. Twenty human upper incisors were selected and one 1 mm slice was obtained from the cervical third of each root. On the coronal surface of each slice, four 0.9 mm wide holes were drilled through the dentine. Standardized irrigation was performed and holes were filled with one of the four tested sealers: AH Plus, MTA Fillapex, MTAe, and MTAe-HA. The filled slices were stored in a PBS solution (pH 7.2) for 7 days at 37 °C. A push-out assessment was performed with a 0.7 mm plunger tip. Load was applied at a crosshead speed of 0.5 mm/min until sealer displacement. The results were expressed in MPa. The Kruskal-Wallis test was applied to assess the effect of each sealer on the push-out bond strength. Mann-Whitney with Bonferroni correction was used to isolate the differences. The alpha-type error was set at 0.05. Significant differences among medians values obtained by materials were observed (p<0.001). AH Plus displayed the highest value of bond strength (p<0.001). In contrast, MTA Fillapex presented the lowest bond strength among all tested sealers (p<0.001). Experimental sealers showed intermediary bond strength values, with no statistical differences between them (p>0.05). In conclusion, experimental root canal sealers presented suitable bond strength outcomes when compared to MTA Fillapex.


Assuntos
Compostos de Alumínio/química , Compostos de Cálcio/química , Etilenoglicol/química , Etilenoglicóis/química , Teste de Materiais , Óxidos/química , Materiais Restauradores do Canal Radicular/química , Salicilatos/química , Silicatos/química , Colagem Dentária/métodos , Combinação de Medicamentos , Humanos
6.
Inflammation ; 41(4): 1349-1360, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29654432

RESUMO

Salicytamide is a new drug developed through molecular modelling and rational drug design by the molecular association of paracetamol and salicylic acid. This study was conducted to assess the acute oral toxicity, antinociceptive, and antioedematogenic properties of salicytamide. Acute toxicity was based on the OECD 423 guidelines. Antinociceptive properties were investigated using the writhing, hot plate and formalin tests in Swiss mice. Antioedematogenic properties were evaluated using the carrageenan-induced paw oedema model and croton oil-induced dermatitis in Wistar rats. Salicytamide did not promote behavioural changes or animal deaths during acute oral toxicity evaluation. Furthermore, salicytamide exhibited peripheral antinociceptive activity as evidenced by the reduction in writhing behaviour (ED50 = 4.95 mg/kg) and licking time in the formalin test's inflammatory phase. Also, salicytamide elicited central antinociceptive activity on both hot plate test and formalin test's neurogenic phase. Additionally, salicytamide was effective in reducing carrageenan or croton oil-induced oedema formation. Overall, we have shown that salicytamide, proposed here as a new NSAID candidate, did not induce oral acute toxicity and elicited both peripheral antinociceptive effects (about 10-25 times more potent than its precursors in the writhing test) and antioedematogenic properties. Salicytamide also presented central antinociceptive activity, which seems to be mediated through opioid-independent mechanisms. These findings reveal salicytamide as a promising antinociceptive/antioedematogenic drug candidate.


Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Desenho de Fármacos , Acetaminofen/química , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Edema/tratamento farmacológico , Camundongos , Nociceptividade/efeitos dos fármacos , Dor/tratamento farmacológico , Ratos Wistar , Salicilatos/química
7.
Braz. dent. j ; 29(2): 195-201, Mar.-Apr. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951536

RESUMO

Abstract This study investigated the bond strength of two experimental root canal sealers based on MTA and butyl ethylene glycol disalicylate: MTAe and MTAe-HA. The reference materials used for comparison were AH Plus and MTA Fillapex. Twenty human upper incisors were selected and one 1 mm slice was obtained from the cervical third of each root. On the coronal surface of each slice, four 0.9 mm wide holes were drilled through the dentine. Standardized irrigation was performed and holes were filled with one of the four tested sealers: AH Plus, MTA Fillapex, MTAe, and MTAe-HA. The filled slices were stored in a PBS solution (pH 7.2) for 7 days at 37 °C. A push-out assessment was performed with a 0.7 mm plunger tip. Load was applied at a crosshead speed of 0.5 mm/min until sealer displacement. The results were expressed in MPa. The Kruskal-Wallis test was applied to assess the effect of each sealer on the push-out bond strength. Mann-Whitney with Bonferroni correction was used to isolate the differences. The alpha-type error was set at 0.05. Significant differences among medians values obtained by materials were observed (p<0.001). AH Plus displayed the highest value of bond strength (p<0.001). In contrast, MTA Fillapex presented the lowest bond strength among all tested sealers (p<0.001). Experimental sealers showed intermediary bond strength values, with no statistical differences between them (p>0.05). In conclusion, experimental root canal sealers presented suitable bond strength outcomes when compared to MTA Fillapex.


Resumo Esse estudo investigou a resistência de união de dois cimentos endodônticos experimentais à base de MTA e butiletilenoglicol dissalicilato: MTAe e MTAe. Os materiais de referência utilizados para comparação foram os cimentos endodônticos MTA Fillapex e AH Plus. Vinte incisivos superiores humanos foram selecionados e um slice dentinário de 1 mm de espessura foi obtido do terço cervical de cada raiz. Na superfície coronária de cada slice, quatro orifícios com 0,9 mm de diâmetro foram confeccionados através da dentina. Uma irrigação padronizada foi realizada e os orifícios foram preenchidos com um dos quatro cimentos endodônticos avaliados: AH Plus, MTA Fillapex, MTAe, e MTAe-HA. Os slices preenchidos foram armazenados em solução PBS (pH 7,2) durante 7 dias a 37°C. O ensaio de push-out foi realizado por meio de um dispositivo com 0,7 mm de diâmetro. A carga foi aplicada com a velocidade de 0,5 mm/min até a obtenção de deslocamento do material obturador. Os resultados foram expressos em MPa. O teste de Kruskal-Wallis foi aplicado para avaliar o efeito da resistência de união de cada cimento endodôntico. O teste de Mann-Whitney com correção de Bonferroni foi utilizado para isolamento das diferenças. O erro do tipo-alfa foi fixado em 0,05. Diferenças significantes entre os valores de medianas obtidos pelos materiais foram observados (p<0,001). O AH Plus demonstrou os maiores valores de resistência de união (p<0,001). Em contraste, o MTA Fillapex apresentou a menor resistência de união entre todos os cimentos testados (p<0,001). Os cimentos experimentais demonstraram valores intermediários, com ausência de diferenças estatísticas entre si (p>0,05). Em conclusão, os cimentos endodônticos experimentais à base de MTA e butiletilenoglicol dissalicilato apresentaram resultados adequados de resistência de união quando comparados ao MTA Fillapex.


Assuntos
Humanos , Óxidos/química , Teste de Materiais , Compostos de Cálcio/química , Compostos de Alumínio/química , Etilenoglicol/química , Etilenoglicóis/química , Materiais Restauradores do Canal Radicular/química , Salicilatos/química , Colagem Dentária/métodos , Silicatos/química , Combinação de Medicamentos
8.
Molecules ; 23(2)2018 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-29382081

RESUMO

Benzoyltryptamine analogues act as neuroprotective and spasmolytic agents on smooth muscles. In this study, we investigated the ability of N-salicyloyltryptamine (STP) to produce vasorelaxation and determined its underlying mechanisms of action. Isolated rat mesenteric arteries with and without functional endothelium were studied in an isometric contraction system in the presence or absence of pharmacological inhibitors. Amperometric experiments were used to measure the nitric oxide (NO) levels in CD31+ cells using flow cytometry. GH3 cells were used to measure Ca2+ currents using the whole cell patch clamp technique. STP caused endothelium-dependent and -independent relaxation in mesenteric rings. The endothelial-dependent relaxations in response to STP were markedly reduced by L-NAME (endothelial NO synthase-eNOS-inhibitor), jHydroxocobalamin (NO scavenger, 30 µM) and ODQ (soluble Guanylyl Cyclase-sGC-inhibitor, 10 µM), but were not affected by the inhibition of the formation of vasoactive prostanoids. These results were reinforced by the increased NO levels observed in the amperometric experiments with freshly dispersed CD31+ cells. The endothelium-independent effect appeared to involve the inhibition of voltage-gated Ca2+ channels, due to the inhibition of the concentration-response Ca2+ curves in depolarizing solution, the increased relaxation in rings that were pre-incubated with high extracellular KCl (80 mM), and the inhibition of macroscopic Ca2+ currents. The present findings show that the activation of the NO/sGC/cGMP pathway and the inhibition of gated-voltage Ca2+ channels are the mechanisms underlying the effect of STP on mesenteric arteries.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Endotélio Vascular/metabolismo , Artérias Mesentéricas/metabolismo , Óxido Nítrico/metabolismo , Salicilatos/farmacologia , Guanilil Ciclase Solúvel/metabolismo , Triptaminas/farmacologia , Vasodilatação/efeitos dos fármacos , Animais , Masculino , Ratos , Ratos Wistar , Salicilatos/química , Triptaminas/química
9.
Curr Pharm Des ; 23(44): 6841-6848, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28571537

RESUMO

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most commonly used medications in inflammatory illnesses. However, the gastrointestinal bleeding and toxicity associated with NSAIDs long term use prompted the quest towards investigations for new anti-inflammatory agents. Natural and natural-derived molecules proved its anti-inflammatory efficacy in vitro as well as in vivo. Given this background, the scope of this research involves structural changes of the natural polyphenol (tyrosol) generating two new salicylate derivatives and testing their biological properties, focusing on anti-inflammatory effects assessed in vitro and in vivo assays. The first molecular modification was the introduction of a carboxylic acid group adjacent to the phenol group present in this compound, which creates a new salicylate-like tyrosol. In addition, the acetylation of phenol group in this molecule produced an acetylsalicylate derivative, which may be regarded as aspirin-like natural polyphenol. Interestingly, tyrosol and its novel derivatives attenuated the edema in acute inflammatory response on carrageenan- induced local inflammation in mice. In addition, our results demonstrated that tyrosol and its novel derivatives were able to reduce the chemotaxis of neutrophil assessed in vitro model by chemo attractant (fMLP). Furthermore, only derivative 2 was able to reduce this effect in the acute inflammatory model. In (DPPH)- scavenging activity, tyrosol derivatives demonstrated a minor antioxidant activity, which may suggest that radical scavenging is not a major pathway involved in the anti-inflammatory effects of these derivatives. Salicylate-like tyrosol derivatives are of particular interest for future studies.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Edema/tratamento farmacológico , Inflamação/tratamento farmacológico , Álcool Feniletílico/análogos & derivados , Salicilatos/síntese química , Salicilatos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Carragenina , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Inflamação/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Álcool Feniletílico/síntese química , Álcool Feniletílico/química , Álcool Feniletílico/farmacologia , Salicilatos/química , Relação Estrutura-Atividade
10.
Microsc Res Tech ; 80(9): 1036-1048, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28548699

RESUMO

The aim was to evaluate the cytocompatibility of the AH Plus and Sealapex associated with amoxicillin (AA) in a quantity of 10% by total weight of the sealers, the flow and setting time of these sealers with 10%-0.25% AA and antibiofilm activity of these sealers associated with AA in a concentration that does not alter their physical properties (1%). Cytocompatibility was assessed by MTT, neutral red and cytoskeletal fluorescence assays. Setting time and flow was evaluated using the specifications of ISO 6876/2012. For the antibiofilm evaluation, materials were placed in direct contact with E. faecalis biofilm induced on dentin blocks. The incorporation of AA into the sealers did not diminish the viability of the fibroblasts and did not cause structural changes in the cytoskeletal. The flow of AH Plus + AA at 1.0; 0.5 and 0.25%, and of Sealapex + AA at 5.5; 2.5; 1.0; 0.5 and 0.25% were within the specifications of the ISO 6876. AH Plus, and AH Plus + AA at 1.0; 0.50 and 0.25% presented a setting time of 730, 439, 455, and 474 min., respectively. Sealapex - pure or associated with AA did not set completely. The addition of 1% AA to the sealers did not increase their antibiofilm activity. It was concluded that the incorporation of 10% AA caused no toxic effects on fibroblasts, but harmed the physical properties. The addition of AA in concentration that does not affect the physical properties of the sealers did not increase their antibiofilm activity.


Assuntos
Amoxicilina , Antibacterianos , Materiais Restauradores do Canal Radicular , Amoxicilina/química , Amoxicilina/farmacologia , Amoxicilina/toxicidade , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Biofilmes/efeitos dos fármacos , Hidróxido de Cálcio/química , Hidróxido de Cálcio/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Camundongos , Microscopia de Fluorescência , Materiais Restauradores do Canal Radicular/química , Materiais Restauradores do Canal Radicular/farmacologia , Materiais Restauradores do Canal Radicular/toxicidade , Salicilatos/química , Salicilatos/farmacologia
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