Polo Universitario do Alto da Ajuda

Lisbon, Portugal

Polo Universitario do Alto da Ajuda

Lisbon, Portugal
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Brites C.M.,Instituto Nacional dos Recursos Biologicos | Trigo M.J.,Instituto Nacional dos Recursos Biologicos | Carrapico B.,Polo Universitario do Alto da Ajuda | Alvina M.,University of Valparaíso | And 2 more authors.
Nutrition Research | Year: 2011

White wheat bread is a poor source of dietary fiber, typically containing less than 2%. A demand exists for the development of breads with starch that is slowly digestible or partially resistant to the digestive process. The utilization of maize flour and resistant starch is expected to reduce the release and absorption of glucose and, hence, lower the glycemic index of bread. This study was undertaken to investigate the hypothesis that a diet of maize bread, as produced and consumed in Portugal, would have beneficial metabolic effects on rats compared to white wheat bread. We also hypothesized that the effect of resistant starch on glycemic response could be altered by the use of different formulations and breadmaking processes for wheat and maize breads. Resistant starch (RS) was incorporated into formulations of breads at 20% of the inclusion rate of wheat and maize flours. Assays were conducted with male Wistar rats (n = 36), divided into four groups and fed either wheat bread, RS-wheat bread, maize bread, and RS-maize bread to evaluate feed intake, body weight gain, fecal pH, and postprandial blood glucose response (glycemic response). Blood triglycerides, total cholesterol concentrations, and liver weights were also determined. The maize bread group presented higher body weight gain and cholesterol level, lower fecal pH, and postprandial blood glucose response than the wheat bread group. The RS-wheat bread group showed significant reductions in feed intake, fecal pH, postprandial blood glucose response, and total cholesterol. The RS-maize group displayed significant reductions of body weight gain, fecal pH, and total cholesterol levels; however, for the glycemic response, only a reduction in fasting level was observed. These results suggest that maize bread has a lower glycemic index than wheat bread, and the magnitude of the effect of RS on glycemic response depends of type of bread. © 2011 Elsevier Inc.

Santos N.,University of Minho | Santos N.,Pygargus Lda | Santos N.,Polo Universitario do Alto da Ajuda | Geraldes M.,National Institute of Biological Resources | And 3 more authors.
PLoS ONE | Year: 2010

Background: To obtain robust epidemiological information regarding tuberculosis (TB) in wildlife species, appropriate diagnostic methods need to be used. Wild boar (Sus scrofa) recently emerged as a major maintenance host for TB in some European countries. Nevertheless, no data is available to evaluate TB post-mortem diagnostic methods in hunter-harvested wild boar. Methodology/Principal Findings: Six different diagnostic methods for TB were evaluated in parallel in 167 hunter-harvested wild boar. Compared to bacteriological culture, estimates of sensitivity of histopathology was 77.8%, gross pathology 72.2%, PCR for the MPB70 gene 66.7%, detection of acid-fast bacilli (AFB) in tissue contact smears 55.6% and in histopathology slides 16.7% (estimated specificity was 96.7%, 100%, 100%, 94.4% and 100%, respectively). Combining gross pathology with stained smears in parallel increased estimated sensitivity to 94.4% (94.4% specificity). Four probable bacteriological culture false-negative animals were identified by Discriminant Function Analysis. Recalculating the parameters considering these animals as infected generated estimated values for sensitivity of bacteriology and histopathology of 81.8%, gross pathology 72.7%, PCR for the MPB70 gene 63.6%, detection of AFB in tissue contact smears 54.5% and in histopathology slides 13.6% (estimated specificity was 100% for gross pathology, PCR, bacteriology and detection of AFB in histopathology slides, 96.7% for histopathology and 94.4% for stained smears). Conclusions/Significance: These results show that surveys for TB in wild boar based exclusively on gross pathology considerably underestimate prevalence, while combination of tests in parallel much improves sensitivity and negative predictive values. This finding should thus be considered when planning future surveys and game meat inspection schemes. Although bacteriological culture is the reference test for TB diagnosis, it can generate false-negative results and this should be considered when interpreting data. © 2010 Santos et al.

Conte G.,University of Pisa | Jeronimo E.,Polo Universitario do Alto da Ajuda | Serra A.,University of Pisa | Bessa R.J.B.,Polo Universitario do Alto da Ajuda | Mele M.,University of Pisa
Italian Journal of Animal Science | Year: 2012

The effect of replacement of dietary sunflower oil (SO) with linseed oil (LO) on Stearoyl CoA desaturase (SCD) gene expression was investigated. Thirty-six lambs were randomly assigned to four groups and fed with one of the experimental diets, consisting of lucerne pellets with oil (60 g/Kg). The diets varied in the percentage of the oil supplemented and were: 100% SO; 66.6% SO plus 33.3% LO; 33.3% SO plus 66.6% LO and 100% LO. The trial period was of 7 weeks. Longissimus dorsi was removed from each carcass and stored at -80°C until the analysis. Total fatty acids composition was determined by gas-chromatograph, while SCD gene expression was assessed by RealTime Reverse-Transcription PCR. Replacement of SO with LO decreases significantly the SCD mRNA content with a concomitant increment of polyunsatured fatty acids (PUFA) n-3. These results are related to the higher level of PUFA n-3 present in linseed than sunflower. Although, there were differences on mRNA level, there was not a simultaneously changes on SCD activity. In conclusion, PUFA n-3 act on the regulation of mRNA SCD level without affecting the activity of the relative enzyme. © G. Conte et al., 2012 Licensee PAGEPress, Italy.

Oliveira P.,IBB Institute for Biotechnology And Bioengineering | Borges P.,IBB Institute for Biotechnology And Bioengineering | Pinto R.R.,IBB Institute for Biotechnology And Bioengineering | Pinto R.R.,Polo Universitario do Alto da Ajuda | And 4 more authors.
Applied Catalysis A: General | Year: 2010

In this study, we analysed the influence of the acidity of a ZSM-5 catalyst on the catalytic transformation of various short-chain olefins (ethylene, propylene and 1-butene). Four ZMS-5 catalysts with different acid strength distributions were studied at different temperatures and partial pressures. The results were fitted using a kinetic model based on a network mechanism, which details the products by type (olefins, paraffins and aromatics) and number of carbon atoms. Polanyi-type equations, supported on quantum chemical calculations, were used to derive quantitative relations between the ammonia adsorption energy, used as a measure of the acidity of a given acid site, and the energetics of the various steps involved in the reaction. It was observed that, although the qualitative aspects of the reactivity differs from olefin to olefin and according to the catalyst's acidity, the model is able to describe both activity and product distribution for all catalysts, reactants and conditions using a single reaction scheme and a single set of kinetic parameters. © 2010 Elsevier B.V. All rights reserved.

Jeronimo E.,Unidade de Investigacao em Producao Animal | Jeronimo E.,Polo Universitario do Alto da Ajuda | Alves S.P.,Unidade de Investigacao em Producao Animal | Alves S.P.,Abel Salazar Biomedical Sciences Institute | And 5 more authors.
Animal Feed Science and Technology | Year: 2010

The effect of dietary sodium bentonite and a blend of sunflower and linseed oils at 1:2 (v/v) on growth, carcass and meat quality and fatty acid (FA) composition of longissimus dorsi muscle of lambs was studied. Thirty-two Merino Branco lambs with initial live weights (LW) of 16.2 ± 2.93 kg were divided according to a completely randomized experimental design within a 2 × 2 factorial arrangement of treatments in order to evaluate effects of the vegetable oil blend supplementation (0 g/kg versus 60 g/kg DM) and sodium bentonite inclusion in diets (0 g/kg versus 20 g/kg DM). The basal diet consisted of pellets with 750 g dehydrated lucerne/kg DM and 250 g manioc/kg DM. The experimental period was 6 weeks. Bentonite affected neither daily LW gain, dry matter (DM) intake, nor carcass composition. However, bentonite decreased the a* meat colour parameter (redness; P=0.004). Oil supplementation affected neither daily LW gain, nor DM intake. However, it increased fat proportion in chump and shoulder cuts (P<0.001), as well as kidney and knob channel fat (P<0.001) while it decreased muscle proportion in the dissected cuts (P<0.001). Oil supplementation increased intramuscular fat (P<0.001) and most meat FA. Polyunsaturated FA (PUFA) increased 23% with oil supplementation (P=0.007), mostly by increasing proportions of n-3 PUFA and biohydrogenation derived PUFA. Oil supplementation decreased n-6 long chain PUFA (P<0.001). The proportion of n-3 long chain PUFA was not affected by oil supplementation, so the increase in n-3 PUFA from 1.99 g/100 g of total FA to 4.23 g/100 g of total FA (P<0.001) was mainly due to the increase of α-linolenic acid (P<0.001). However, when expressed in mg/100 g of meat, oil supplementation increased n-3 long chain PUFA concentration from 20 to 31 mg (P<0.001). All biohydrogenation intermediates (BI) increased with oil supplementation, except for cis-11 18:1 which decreased, and cis-13 18:1 and trans-8, cis-10 18:2 which were unchanged. Conjugated linoleic acid increased with oil supplementation from 0.50 to 1.72 g/100 g of total FA (P<0.001). Bentonite did not affect most meat FA, although effects occurred on some BI. Bentonite increased trans-11 18:1, but prevented the increase of trans-10 18:1 in meat from oil supplemented lambs (P<0.001). Trans-11, cis-15 18:2, cis-9, cis-15 18:2 and cis-9, trans-11, cis-15 18:3 increased with dietary bentonite inclusion. © 2010 Elsevier B.V. All rights reserved.

Jeronimo E.,Unidade de Investigacao em Producao Animal | Jeronimo E.,Polo Universitario do Alto da Ajuda | Alfaia C.M.M.,Polo Universitario do Alto da Ajuda | Alves S.P.,Unidade de Investigacao em Producao Animal | And 7 more authors.
Meat Science | Year: 2012

Thirty-six Merino Branco lambs were assigned to six dietary treatments: control diet (C) consisting of 90% dehydrated lucerne and 10% wheat bran; C with 6% of oil blend (CO); C with 2.5% of grape seed extract (GS); GS with 6% of oil blend (GSO); C with 25% of Cistus ladanifer (CL), and CL with 6% of oil blend (CLO). Meat lipid and colour stability was then evaluated during 7. days of storage. The effect of inclusion of grape seed extract and C. ladanifer in diets on meat sensory properties was also evaluated. Meat antioxidant potential, determined after oxidation induction by a ferrous/hydrogen peroxide system, decreased with oil supplementation (P< 0.001), but inclusion of grape seed extract and C. ladanifer in diets protected the meat against lipid oxidation (P= 0.036). Meat colour was not affected by diets. Inclusion of grape seed extract and C. ladanifer in diets did not change the sensory properties of meat. © 2012 Elsevier Ltd.

Jeronimo E.,Unidade de Investigacao em Producao Animal | Jeronimo E.,Polo Universitario do Alto da Ajuda | Alves S.P.,Unidade de Investigacao em Producao Animal | Alves S.P.,Abel Salazar Biomedical Sciences Institute | And 7 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010

Thirty-six lambs were used in a 6 week experiment to evaluate the effect of vegetable oil blend supplementation (0 vs 60 g/kg of dry matter (DM)) and two dietary condensed tannin sources, grape seed extract (0 vs 25 g/kg of DM) and Cistus ladanifer L. (0 vs 250 g/kg of DM), on fatty acid (FA) composition of abomasal digesta and intramuscular polar and neutral lipids. Grape seed extract did not affect the FA profile of abomasal digesta or muscle lipid fractions. C. ladanifer had a minor effect in lambs fed diets with no oil but greatly changed the abomasal and muscle FA profiles in oilsupplemented lambs. It decreased 18:0 and increased 18:1 trans-11 in abomasal digesta and increased 18:1 trans-11 and 18:2 cis-9,trans-11 (P = 0.062) in muscle neutral lipids, resulting in an important enrichment of meat 18:2 cis-9,trans-11 when compared to other oil-supplemented diets (19.2 vs 41.7 mg/100 g of muscle). © 2010 American Chemical Society.

PubMed | Polo Universitario do Alto da Ajuda and Instituto Nacional Of Investigacao Agraria E Veterinaria
Type: Journal Article | Journal: Journal of helminthology | Year: 2014

Stray cats live in high-density colonies in urban areas and pose a health hazard to household cats and humans. In Portugal, information on the parasitic fauna of stray cats is limited and relies mostly on results from faecal analysis. The present survey aimed to determine the prevalence, diversity and intensity of parasites in stray cats from the urban area of Lisbon by means of parasitological necropsy. Internal organs were collected from 162 cats captured in different areas of the city and systematically subjected to parasitological dissection. Helminths were identified by macro- and microscopic examination and protozoa by faecal floatation and sedimentation techniques. The overall prevalence of parasites was 90.7% (95% confidence interval (CI): 85.3-94.6%). A total of 12 parasite species was recorded: Cystoisospora felis (14.2%), Cystoisospora rivolta (46.3%), Sarcocystis sp. (1.2%), Ancylostoma tubaeforme (19.1%), Toxocara cati (38.3%), Ollulanus tricuspis (30.9%), Aelurostrongylus abstrusus (12.4%), Eucoleus aerophilus (0.6%), Taenia taeniaeformis (3.1%), Dipylidium caninum (53.1%), Joyeuxiella pasqualei (15.4%) and Diplopylidium nlleri (3.7%). Overall mean species richness was 2.36 1.52. Helminth mean intensity was highest for O. tricuspis (285.8), followed by D. caninum (42.4), J. pasqualei (14.4), A. tubaeforme (8.1) and T. cati (5.9). The prevalence and variety of parasites found in our sampling are substantially higher than the numbers previously reported in Portugal. Some of the parasites, including T. cati and A. tubaeforme, are zoonotic, which emphasizes the need for parasite control strategies based on demographic containment of stray cat populations in urban areas to promote public health protection.

Pereira T.G.,INRB | Batista I.,INRB | Bandarra N.M.,INRB | Ferreira J.,INRB | And 2 more authors.
International Journal of Food Science and Technology | Year: 2013

The main objective of this study was to compare the proximate chemical composition and fatty acid profile of migrating allis shad (MS) and resident allis shad (RS) and to evaluate the nutritional value of fried migrating allis shad. No significant differences in the proximate chemical composition between males and females of each stock were obtained. However, MS fish had a significantly higher fat content than RS fish. The monounsaturated fatty acids group was the dominant in MS fish and oleic acid presented the highest percentage. Docosahexaenoic acid followed by eicosapentaenoic acid were the main PUFA in fish from both stocks. However, RS fish had higher total ω6 than MS fish due to its higher percentage of linoleic acid and arachidonic acid. Frying resulted in a significant reduction in water content and affected significantly the proximate chemical composition and the fatty acid profile, particularly the palmitic, oleic and linoleic acid. © 2013 Institute of Food Science and Technology.

PubMed | Polo Universitario do Alto da Ajuda
Type: | Journal: Methods in enzymology | Year: 2012

Cellulosomes are highly efficient nanomachines that play a fundamental role during the anaerobic deconstruction of complex plant cell wall carbohydrates. The assembly of these complex nanomachines results from the very tight binding of repetitive cohesin modules, located in a noncatalytic molecular scaffold, and dockerin domains located at the C-terminus of the enzyme components of the cellulosome. The number of enzymes found in a cellulosome varies but may reach more than 100 catalytic subunits if cellulosomes are further organized in polycellulosomes, through a second type of cohesin-dockerin interaction. Structural studies have revealed how the cohesin-dockerin interaction mediates cellulosome assembly and cell-surface attachment, while retaining the flexibility required to potentiate catalytic synergy within the complex. Methods that might be applied for the production, purification, and structure determination of cohesin-dockerin complexes are described here.

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