139 research outputs found
Composição esterólica e em ácidos gordos de azeites monovarietais provenientes das regiões de Elvas, Castelo Branco e Santarém
Comunicação apresentada no III Simpósio Nacional de Olivicultura que decorreu em Castelo Branco, na Escola Superior Agrária do Instituto Politécnico de Castelo Branco, de 29 a 31 de Outubro de 2003.Neste trabalho apresenta-se um estudo efectuado em cinco azeites monovarietais
(Olea europaea ‘Cordovil De Castelo Branco’, ‘Cobrançosa’, ‘Conserva De Elvas’,
‘Galega Vulgar’ e ‘Picual’). O estudo reporta-se a três campanhas consecutivas
(2000/03) e o material experimental provém de olivais situados em três regiões
portuguesas, nomeadamente Elvas, Castelo Branco e Santarém. Os azeites foram
extraídos em equipamento Oliomio e as análises foram: ácidos gordos, esteróis e álcoois
triterpénicos (eritrodiol + uvaol). Dos resultados obtidos, o azeite ‘Cordovil De Castelo
Branco’ destaca-se pelos seus teores elevados em eritrodiol + uvaol nas três regiões em
estudo. Por seu turno, o teor de ácido oleico do azeite ‘Galega Vulgar’ permite
distinguir cada uma das regiões, enquanto no azeite ‘Cobrançosa’ o teor em esteróis
totais distingue as três regiões
Fibroblast migration and collagen deposition during dermal wound healing: mathematical modelling and clinical implications,
The extent to which collagen alignment occurs during dermal wound healing determines the severity of scar tissue formation. We have modelled this using a multiscale approach, in which extracellular materials, for example collagen and fibrin, are modelled as continua, while fibroblasts are considered as discrete units. Within this model framework, we have explored the effects that different parameters have on the alignment process, and we have used the model to investigate how manipulation of transforming growth factor-β levels can reduce scar tissue formation. We briefly review this body of work, then extend the modelling framework to investigate the role played by leucocyte signalling in wound repair. To this end, fibroblast migration and collagen deposition within both the wound region and healthy peripheral tissue are considered. Trajectories of individual fibroblasts are determined as they migrate towards the wound region under the combined influence of collagen/fibrin alignment and gradients in a paracrine chemoattractant produced by leucocytes. The effects of a number of different physiological and cellular parameters upon the collagen alignment and repair integrity are assessed. These parameters include fibroblast concentration, cellular speed, fibroblast sensitivity to chemoattractant concentration and chemoattractant diffusion coefficient. Our results show that chemoattractant gradients lead to increased collagen alignment at the interface between the wound and the healthy tissue. Results show that there is a trade-off between wound integrity and the degree of scarring. The former is found to be optimized under conditions of a large chemoattractant diffusion coefficient, while the latter can be minimized when repair takes place in the presence of a competitive inhibitor to chemoattractants
Intranasal Resveratrol Nanoparticles Enhance Neuroprotection in a Model of Multiple Sclerosis.
Resveratrol is a natural polyphenol which has a very low bioavailability but whose antioxidant, anti-inflammatory and anti-apoptotic properties may have therapeutic potential for the treatment of neurodegenerative diseases such as multiple sclerosis (MS). Previously, we reported the oral administration of resveratrol nanoparticles (RNs) elicited a neuroprotective effect in an experimental autoimmune encephalomyelitis (EAE) mouse model of MS, at significantly lower doses than unconjugated resveratrol (RSV) due to enhanced bioavailability. Furthermore, we demonstrated that the intranasal administration of a cell-derived secretome-based therapy at low concentrations leads to the selective neuroprotection of the optic nerve in EAE mice. The current study sought to assess the potential selective efficacy of lower concentrations of intranasal RNs for attenuating optic nerve damage in EAE mice.
EAE mice received either a daily intranasal vehicle, RNs or unconjugated resveratrol (RSV) for a period of thirty days beginning on the day of EAE induction. Mice were assessed daily for limb paralysis and weekly for visual function using the optokinetic response (OKR) by observers masked to treatment regimes. After sacrifice at day 30, spinal cords and optic nerves were stained to assess inflammation and demyelination, and retinas were immunostained to quantify retinal ganglion cell (RGC) survival.
Intranasal RNs significantly increased RGC survival at half the dose previously shown to be required when given orally, reducing the risk of systemic side effects associated with prolonged use. Both intranasal RSV and RN therapies enhanced RGC survival trends, however, only the effects of intranasal RNs were significant. RGC loss was prevented even in the presence of inflammatory and demyelinating changes induced by EAE in optic nerves.
The intranasal administration of RNs is able to reduce RGC loss independent of the inflammatory and demyelinating effects on the optic nerve and the spinal cord. The concentration of RNs needed to achieve neuroprotection is lower than previously demonstrated with oral administration, suggesting intranasal drug delivery combined with nanoparticle conjugation warrants further exploration as a potential neuroprotective strategy for the treatment of optic neuritis, alone as well as in combination with glucocorticoids
Evaluation of mitochondrial activity in spermatozoids after collecting and posthawing in Boer and Alpine goats in autumn and spring
Caprine spermatozoa undergo glycolisis and mitocondrial respiration to keep the necessary
energy balance to their transportation and other cellular functions. An objective test to evaluate
quantitatively and qualitatively mitochondrial activity in caprine spermatozoa was applied in the analysis
of semen samples of 9 bucks from Boer (n=5) and Alpine (n=4) breeds. Samples were collected and
frozen in TRIS medium in two different year seasons. Semen collection was performed using artificial
vagina to obtain 135 ejaculates, which were used to post-collection and post-frozen extended in sildes.
To determine mitochondrial activity, a citochemical procedure developed and validated for HRUDKA
(1987) was used. The technique is based on the enzymatic 3,3-diaminobenzidine (DAB) oxidation,
where the reagent is polymerized and attached to the mitochondrial membrane throughout the spermatic
intermediary piece. A medium level of citochemical activity (IAC) was determined as being 74,37%,
74,37% during Autumn and 77% e 77,75% during Spring for Boer and Alpine breeds, respectively. For
post-collection IAC levels were 85,62% and 85,93 and for post-frozen 66% and 67,25% for Boer and
Alpine breeds, respectively. ANOVA test was used to evaluate breed, post-collection, post-frozen, IAC
rates and year season parameters. Differences were not noticed for breed, IAC rates and year season.
Nonetheless, there was a significant effect among samples for post-collection and post-frozen analysis
(POs espermatozóides caprinos realizam a respiração mitocondrial, mantendo um balanço energético
necessário para o transporte e as demais funções celulares. Um teste objetivo de avaliação quantitativa e
qualitativa da atividade mitocondrial em espermatozóides caprinos foi aplicado no sêmen de nove reprodutores
das raças Boer (n=5) e Alpina (n=4) colhidos e congelados em diluidor TRIS em duas estações. A colheita do
sêmen foi realizada com auxílio da vagina artificial, totalizando 135 ejaculados e foram confeccionados
esfregaços com sêmen pós-colheita e pós-descongelação. Para a determinação da atividade mitocondrial foi
utilizado o procedimento citoquímico desenvolvido e validado por HRUDKA (1987). Esta técnica é baseada
na oxidação da 3,3-diaminobenzidine (DAB) pela enzima em reação em cadeia, onde o reagente é polimerizado
e depositado na bainha mitocondrial ao longo da peça intermediária dos espermatozóides. Foi determinado
um índice médio de atividade citoquímica (IAC) de 74,37%, 74,37% no outono, 77% e 77,75% na primavera.
E 85,62% e 85,93 no pós-colheita, 66% e 67,25% pós-descongelação para as raças Boer e Alpina,
respectivamente. As variáveis raças, pós-colheita e pós-descongelação, classes (IAC), e estação foram
estudadas por meio de ANOVA. Não foram observadas diferenças estatísticas para raças, classes, bem
como para as estações. Entretanto, efeito significativo entre as amostras pós-colheita e pós-descongelação
(
Eficiência do protocolo Ovsynch em ovelhas da raça Santa Inês
Twenty six Santa Inês ewes were asigned to three treatments to evaluate the efficiency of the Ovsynch protocol. In the treatment 1 - control (n= 8), the estrus was synchronized with sponges containing 60 mg MAP for 14 days. On D14, 300 IU eCG were administered. In treatment 2 (n= 9) the Ovsynch protocol was used: 25 µg of GnRH (D0), 37.5 µg of PGF2a (D7) and 25 µg of GnRH (D9). In treatment 3 (n= 9) the modified Ovsynch protocol was used: the administration of PGF2a and second GnRH as two days early. Estrus detection was accomplished using teaser. All ewes were mated twice with 12 hours of interval. Pregnancy rate (PR) was evaluated by ultrasonography 30 days after the end of mating. Estrus response was of 88.46% on average, and without differences among treatments (p>0.05). The interval for onset of estrus was greater (p0.05). Pregnancy rate was significantly greater (p0,05). O intervalo entre o final do tratamento e o início do estro foi maior (p0,05) entre tratamentos. A TP diferiu entre os grupos (37,5%, 62,5% e 25%, respectivamente. p<0,05). Os resultados mostram eficiência superior do protocolo Ovsynch, sob as restantes condições expe-rimentais
Ocorrência, métodos de inoculação e agressividade de Fusarium oxysporum f. sp. cubense em Heliconia spp
Toxicological and pharmacological evaluation of Discaria americana Gillies & Hook (Rhamnaceae) in mice
Structure of the parasite infracommunity of Sciades proops from the Japaratuba River Estuary, Sergipe, Brazil
Parinaud's syndrome secondary to thromboembolism from myocardial infarction associated with myelofibrosis
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