Limonene, a Chemical Compound Related to the Resistance of Eucalyptus Species to Austropuccinia psidii.

The fungus Austropuccinia psidii is a major pathogen of Eucalyptus spp. that damages mainly early-stage leaves. Resistant clones are the most widely used control measure for the rust disease caused by A. psidii. Essential oils produced in the plant-host cells are associated with resistance. However, the chemical characteristics of Eucalyptus leaves at different stages of maturity, associated with resistance or susceptibility to A. psidii, need to be determined. The aims of this study were to characterize the chemical composition of essential oils in Eucalyptus leaves at three developmental stages of clones of three E. urophylla × E. grandis hybrids that exhibit different resistance levels to rust and to identify probable resistance-related compounds from them. The rust severity following inoculation and the quantity and quality of the essential oil extracted by hydrodistillation were determined at the first, third, and fifth leaf stages of the three clones. Identification of the compounds present in the essential oil was determined by gas chromatography coupled with mass spectrometry. No rust was observed on the three leaf stages of the resistant clone or on the fifth leaf stage of the susceptible clones. Limonene was found at high percentages in essential oils from the three leaf stages of the resistant clone and at low percentages in the susceptible clones. In vitro and in vivo tests indicated that low limonene percentages stimulated A. psidii urediniospore germination and were not fungitoxic, whereas high percentages caused complete inhibition of germination and degenerative changes in fungal reproductive structures. The limonene present in Eucalyptus leaves can be considered a chemical compound related to the rust resistance of Eucalyptus spp.

Application of hyperthermia induced by superparamagnetic iron oxide nanoparticles in glioma treatment.

Gliomas are a group of heterogeneous primary central nervous system (CNS) tumors arising from the glial cells. Malignant gliomas account for a majority of malignant primary CNS tumors and are associated with high morbidity and mortality. Glioblastoma is the most frequent and malignant glioma, and despite the recent advances in diagnosis and new treatment options, its prognosis remains dismal. New opportunities for the development of effective therapies for malignant gliomas are urgently needed. Magnetic hyperthermia (MHT), which consists of heat generation in the region of the tumor through the application of magnetic nanoparticles subjected to an alternating magnetic field (AMF), has shown positive results in both preclinical and clinical assays. The aim of this review is to assess the relevance of hyperthermia induced by magnetic nanoparticles in the treatment of gliomas and to note the possible variations of the technique and its implication on the effectiveness of the treatment. We performed an electronic search in the literature from January 1990 to October 2010, in various databases, and after application of the inclusion criteria we obtained a total of 15 articles. In vitro studies and studies using animal models showed that MHT was effective in the promotion of tumor cell death and reduction of tumor mass or increase in survival. Two clinical studies showed that MHT could be applied safely and with few side effects. Some studies suggested that mechanisms of cell death, such as apoptosis, necrosis, and antitumor immune response were triggered by MHT. Based on these data, we could conclude that MHT proved to be efficient in most of the experiments, and that the improvement of the nanocomposites as well as the AMF equipment might contribute toward establishing MHT as a promising tool in the treatment of malignant gliomas.

Especificidade da atividade mioelétrica no agachamento excêntrico declinado em 25º e no agachamento padrão com diferentes sobrecargas / Specificity of the myoelectrical activity on the eccentric decline squat at 25º and standard squat with different overloads

OBJETIVO: O objetivo neste estudo foi comparar a atividade mioelétrica entre o agachamento unilateral declinado e o agachamento unilateral em superfície plana, no deslocamento vertical de duas diferentes quantidades de massa. PARTICIPANTES: Um grupo de oito sujeitos treinados recreacionalmente sem sinais e sintomas de lesões nas extremidades inferiores. PROCEDIMENTOS: Em dias separados, os sujeitos realizaram dois tipos distintos de agachamento unilateral na fase descendente, diferenciados em função da direção da base de sustentação, sendo uma horizontal e outra inclinada a 25º. Os dois tipos de agachamento foram realizados com dois valores de carga, com o peso do próprio corpo e com sobrecarga representativa de 15 repetições máximas (15RM). MENSURAÇÕES: As atividades mioelétricas do reto femoral, vasto lateral, posteriores de coxa mediais (semimembranoso e semitendinoso) e gastrocnêmio medial foram mensuradas nas quatro situações de teste. RESULTADOS: O grupamento muscular quadríceps mostrou-se sensível à magnitude do ângulo de inclinação da plataforma, manifestando maior atividade no agachamento declinado, e não apresentou aumentos na ativação muscular como resposta ao aumento da carga. Os músculos mediais posteriores da coxa e o gastrocnêmio medial não se mostraram sensíveis à angulação da plataforma nem ao aumento da sobrecarga. Apesar das taxas de co-contração não serem semelhantes entre as quatro situações testadas, as diferenças entre elas não se mostraram estatisticamente significativas. CONCLUSÃO: Os resultados confirmaram a maior ativação do quadríceps gerada no agachamento declinado em comparação ao agachamento realizado em superfície plana, sugerindo que esse exercício pode constituir uma alternativa para programas de reabilitação da tendinopatia patelar. Apesar de não termos encontrado diferenças estatisticamente significativas em relação à co-contração muscular, os achados sugerem que esse exercício deve ser utilizado com...

OBJECTIVE: The aim of this study was to compare the myoelectrical activity between the single-leg decline squat and the single-leg standard squat, with two different overloads. PARTICIPANTS: A group of eight recreationally trained subjects with no signs or symptoms of injury in the lower limb. PROCEDURES: On different days, the subjects performed two distinct kinds of unilateral eccentric squat, differentiated by the direction of the base of support, being one flat and the other declined at 25º. These two squats were carried out with two different overloads: with no extra overload and with an overload that represented 15 maximum repetitions (RM). OUTCOME MEASURES: The myoelectrical activities of the rectus femoris, vastus lateralis, medial hamstrings and gastrocnemius medialis were measured in the four test conditions (Flat and Decline Squat with and without extra overload). RESULTS: The quadriceps muscles were sensitive to the platform angle, showing greater activity on the decline squat; however, they did not show increase in the activation when overload was added. The medial hamstrings and gastrocnemius medialis were not sensitive to the platform angle or to the overload increase. In spite of the alterations in the muscular co-contraction ratio in several situations, we did not find any statistically significant differences among the four conditions tested. CONCLUSION: The results confirmed the higher activation of quadriceps generated in the decline squat compared to the standard squat, suggesting that this exercise is an interesting choice for rehabilitation management of patellar tendinopathy. Despite the non-significant statistical differences regarding muscular co-contraction, this exercise should be used with caution, since muscle synergism is changed as a function of tested variables, altering the specificity of this exercise in relation to sports activities, mainly in the coordination aspect.

Ferromagnetic resonance for the quantification of superparamagnetic iron oxide nanoparticles in biological materials.

The aim of the present work is the presentation of a quantification methodology for the control of the amount of superparamagnetic iron oxide nanoparticles (SPIONs) administered in biological materials by means of the ferromagnetic resonance technique (FMR) applied to studies both in vivo and in vitro. The in vivo study consisted in the analysis of the elimination and biodistribution kinetics of SPIONs after intravenous administration in Wistar rats. The results were corroborated by X-ray fluorescence. For the in vitro study, a quantitative analysis of the concentration of SPIONs bound to the specific AC133 monoclonal antibodies was carried out in order to detect the expression of the antigenic epitopes (CD133) in stem cells from human umbilical cord blood. In both studies FMR has proven to be an efficient technique for the SPIONs quantification per volume unit (in vivo) or per labeled cell (in vitro).

Ferromagnetic resonance for the quantification of superparamagnetic iron oxide nanoparticles in biological materials

The aim of the present work is the presentation of a quantification methodology for the control of the amount of superparamagnetic iron oxide nanoparticles (SPIONs) administeredin biological materials by means of the ferromagnetic resonance technique (FMR) applied to studies both in vivo and in vitro. The in vivo study consisted in the analysis of the eliminationand biodistribution kinetics of SPIONs after intravenous administration in Wistar rats. The results were corroborated by X-ray fluorescence. For the in vitro study, a quantitative analysisof the concentration of SPIONs bound to the specific AC133 monoclonal antibodies was carriedout in order to detect the expression of the antigenic epitopes (CD133) in stem cells from human umbilical cord blood. In both studies FMR has proven to be an efficient technique forthe SPIONs quantification per volume unit (in vivo) or per labeled cell (in vitro).