271 research outputs found
Genetic analysis for sooty mold resistance and heart of palm yield in Archontophoenix.
Palmeiras do gênero Archontophoenix, utilizadas tanto como ornamentais quanto produtoras de palmito de qualidade, são susceptíveis à fumagina, doença associada à infestação por pulgões, que afeta a fotossíntese, o crescimento e a aparência das plantas. Foram avaliados a campo a resistência à fumagina conjuntamente com três caracteres associados ao crescimento em 24 famílias de meios-irmãos, 28 meses após o plantio, a fim de identificar a variabilidade genética para os caracteres resistência à fumagina, altura, diâmetro e número de folhas; estimar as correlações genotípicas e fenotípicas envolvendo esses quatro caracteres; e aplicar a estratégia de seleção usando o índice multiefeitos. Houve diferenças entre as famílias para os caracteres avaliados, sugerindo a possibilidade de seleção. O baixo coeficiente de variação observado para resistência à fumagina (9,48%) indica que o método de avaliação adotado, baseado em escala de notas após observação visual, foi eficiente e prático para comparar níveis de infestação do complexo fungo+pulgão em palmeiras do gênero Archontophoenix. As estimativas da herdabilidade no sentido restrito foram baixas a médias para os caracteres relacionados ao crescimento (0,10, 0,26 e 0,26 para número de folhas, diâmetro e altura da planta, respectivamente) e muito altas (0,91) para resistência à fumagina. Correlação genética positiva foi observada entre resistência à fumagina e altura da planta, indicando que a eliminação de plantas muito susceptíveis pode ser feita sem interferência na seleção indireta para produção de palmito. A estratégia de seleção pelo índice multiefeitos (com ganhos genéticos esperados variando de 6,23 a 11,83%) mostrou-se adequada para melhorar simultaneamente caracteres relacionados ao crescimento e à produção de palmito
Inclusion into PLGA nanoparticles greatly improves the effectiveness of \u3b1-bisabolol to inhibit human Dendritic Cell pro-inflammatory activity
a-bisabolol, a natural sesquiterpene alcohol, has generated considerable interest for its antiinflammatory activity. Since the mechanisms of this anti-inflammatory action remain poorly understood,
we investigated whether a-bisabolol affects the release of pro-inflammatory cytokines IL-12, IL-23, IL-6, and TNFa by human dendritic cells (DCs). We found that a-bisabolol did not induce the secretion of these cytokines and did not affect their release induced upon DC challenge with lipopolysaccharide (LPS), a well-known immune cell stimulator. As a-bisabolol is scarcely ingested by the cells, we wondered hether the inclusion of a-bisabolol into nanoparticles could favor its internalization by DCs and consequently its effects on cytokine secretion. We then prepared and characterized poly(lactic-co-glycolic acid) (PLGA) nanoparticles, with a dynamic light scattering peak centered at 154 nm and a half width at half maximum of about 48 nm. These particles were unable to affect per se cytokine secretion by both resting and LPS stimulated DCs and were internalized by human DCs as demonstrated by confocal microscopy analysis. We then loaded PLGA nanoparticles with a-bisabolol and we observed that PLGA-associated a-bisabolol did not stimulate the cytokine release by resting DCs, but decreased IL-12, IL-23, IL-6, and TNFa secretion by LPS-stimulated DCs. Our results indicate that abisabolol inclusion into PLGA anoparticles represents a very promising tool for designing new antiinflammatory, anti-pyretic and, possibly, immunosuppressive therapeutic strategie
Inclusion of \u3b1-bisabolol into PLGA nanoparticles enhances its pro-apoptotic activity in human tumoral pancreatic cells.
Alfa-Bisabolol (figure 1), a sesquiterpene alcohol present in essential oils derived from a variety of plants, presents pro-apoptotic activity against several human cancer cell lines. Its poor aqueous solubility limits in vitro and in vivo tests. Herein we report a study of the formulation and characterization of alfa-Bisabolol using poly lactide-co-glycolid acid copolymer nanoparticles (PLGA/B).
The human therapeutic treatment of PLGA is approved by US Food and Drug Administration (USFDA) thanks to its biocompatibility. This copolymer is one of the most successfully used in nanomedicine applications since it is hydrolyzed in the body to produce the biodegradable lactic and glycolic acid monomer
Light dependent redox catalysis by Photosystem I complexes encapsulated in organic nanoparticles
Photosystem I (PSI) is a pigment binding multi-subunit protein complexes involved in photosynthesis. PSI is localized in the thylakoid membranes and catalyze the electron transfer reaction from plastocyanin to ferredoxin, as one of the main steps involved in conversion of light energy into chemical energy. PSI is highly efficiency with a photochemical efficiency close to one. Several attempts have doing in the past in order to exploit the high efficiency and high stability of PSI in an extra-cellular context in order to catalyze electron transfer reactions: in this work we present an innovative solution for exploiting the photochemical properties of PSI, by encapsulation of PSI complexes in organic nanoparticles. Nanoparticles offer a protected environment to the encapsulated molecule, giving it the possibility of preserving its functional properties and studying how they change over time. In this work the complete characterization, both morphological and functional, of nanostructures obtained by encapsulation of PSI complexes purified from higher plants with PLGA (poly lactic-co-glycolic acid) polymer is presented. The results obtained by transient absorption and time-resolved fluorescence demonstrate that encapsulated PSI were characterized by an higher photochemcial activity compared to PSI complexes in detergent solution. Moreover, encapsulated PSI maintained the high efficiency observed for several weeks even if exposed to very strong light, being more stable compared to PSI in detergent solution. Finally, the nanostructures obtained by encapsulated PSI were able to catalyze light dependent redox reactions with electron acceptors and donors outside the nanostructures Potential application of these PLGA encapsulated PSI in different fields are thus presented and discussed
Clodronate as a Therapeutic Strategy against Osteoarthritis
Osteoarthritis (OA), the most prevalent musculoskeletal pathology, is mainly characterized by the progressive degradation of articular cartilage due to an imbalance between anabolic and catabolic processes. Consequently, OA has been associated with defects in the chondrocitic differentiation of progenitor stem cells (PSCs). In addition, SOX9 is the transcription factor responsible for PSCs chondrogenic commitment. To evaluate the effects of the non-amino bisphosphonate clodronate in OA patients we investigated SOX9 gene expression in circulating progenitor cells (CPCs) and in an in vitro OA model. We evaluated pain intensity, mental and physical performance in OA patients, as well as serum biomarkers related to bone metabolism. In addition, in order to improve therapeutic strategies, we assayed nanoparticle-embedded clodronate (NPs-clo) in an in vitro model of chondrogenic differentiation. Our data showed upregulation of SOX9 gene expression upon treatment, suggesting an increase in chondrocytic commitment. Clodronate also reduced osteoarticular pain and improved mental and physical performance in patients. Furthermore, NPs-clo stimulated SOX9 expression more efficaciously than clodronate alone. Clodronate may therefore be considered a good therapeutic tool against OA; its formulation in nanoparticles may represent a promising challenge to counteract cartilage degeneration
Connective tissue anomalies in patients with spontaneous cervical artery dissection.
OBJECTIVE: To investigate the prevalence of connective tissue abnormalities in patients with spontaneous cervical artery dissections (sCeAD). METHODS: We systematically assessed clinically detectable signs of connective tissue aberration in a series of consecutive patients with sCeAD and of age- and sex-matched patients with ischemic stroke unrelated to CeAD (non-CeAD IS) by a standard examination protocol including 68 items, and performed extensive molecular investigation for hereditary connective tissue disorders in all patients with sCeAD. RESULTS: The study group included 84 patients with sCeAD (mean age, 44.5 ± 7.8 years; 66.7% men) and 84 patients with non-CeAD IS. None of the patients with sCeAD met clinical or molecular diagnostic criteria for established hereditary connective tissue disorder. Connective tissue abnormalities were detected more frequently in the group of patients with sCeAD than in the group of those with non-CeAD IS (mean number of pathologic findings, 4.5 ± 3.5 vs 1.9 ± 2.3; p < 0.001). Eighty-one patients (96.4%) in the sCeAD group had at least one detectable sign compared with 55 patients (66.7%) in the group with non-CeAD IS (p < 0.001). Skeletal, ocular, and skin abnormalities, as well as craniofacial dysmorphisms, were the clinical signs more strongly associated with sCeAD. Signs suggesting connective tissue abnormality were also more frequently represented in patients with sCeAD than in patients with traumatic CeAD (28.6%, p < 0.001; mean number of pathologic findings, 1.7 ± 3.7, p = 0.045). CONCLUSIONS: Connective tissue abnormalities are frequent in patients with sCeAD. This reinforces the hypothesis that systemic aberrations of the connective tissue might be implicated in the pathogenesis of the disease
Interaction between proatherosclerotic factors and right-to-left shunt on the risk of cryptogenic stroke: the Italian Project on Stroke in Young Adults.
Objective: To explore the interaction effects between cardiac interatrial right-to-left shunt (RLS) and proatherosclerotic factors on the risk of brain ischaemia. Design: Multicentre Italian caseecontrol study. Setting: University hospitals. Participants: 588 patients with cryptogenic stroke (CS) aged ≤45 years and 585 control subjects consecutively enrolled as part of the Italian Project on Stroke in Young Adults. Methods: Interaction effects between RLS and an individual proatherosclerotic score computed from the number of conventional vascular risk factors for the risk of CS were investigated. Data were examined by logistic regression models and expressed as interaction OR or interaction risk difference (RD). Results: CS risk increased with increasing number of proatherosclerotic factors in subjects without RLS (OR 2.73; 95% CI 1.98 to 3.76; RD +0.246; 95% CI +0.17 to +0.32; for subjects with one or more factors), but was higher in subjects with RLS and no additional proatherosclerotic factors (OR 5.14; 95% CI 3.49 to 7.58; RD +0.388; 95% CI +0.31 to +0.47) compared with subjects without RLS and no risk factors. Negative interaction and antagonistic effects between RLS and proatherosclerotic factors were observed (interaction OR 0.52; 95% CI 0.31 to 0.91; interaction RD -0.17; 95% CI -0.29 to -0.05). Conclusions: The influence of RLS on the risk of CS decreases with increasing number of atherosclerotic factors, and is highest when such factors are absent. Individual proatherosclerotic profiles may help to identify patients with CS whose patent foramen ovale is probably pathogenic
Validation of the Italian version of the Movement Disorder Society - Unified Parkinson's Disease Rating Scale.
- …