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- Exploring the therapeutic potential of Quercus ilex acorn extract in papillomavirus-induced lesionsPublication . Medeiros-Fonseca, Beatriz; Faustino-Rocha, Ana I.; Pires, Maria João; Neuparth, Maria João; Vala, Helena; Nóbrega, Carmen; Gouvinhas, Irene; Barros, Ana Novo; Dias, Maria Inês; Barros, Lillian; Bastos, Margarida M. S. M.; Gonçalves, Lio; Félix, Luís; Venâncio, Carlos; Medeiros, Rui; Costa, Rui Miguel Gil da; Oliveira, Paula A.Background and Aim: Papillomaviruses (PVs) infections have been documented in numerous animal species across different regions worldwide. They often exert significant impacts on animal health and livestock production. Scientists have studied natural products for over half a century due to their diverse chemical composition, acknowledging their value in fighting cancer. Acorns (Quercus ilex) are believed to have several unexplored pharmacological properties. This study aimed to evaluate the in vivo safety and cancer chemopreventive activity of an infusion extract of Q. ilex in a transgenic mouse model of human PV (HPV)-16, which developed squamous cell carcinomas through a multistep process driven by HPV16 oncogenes. Materials and Methods: Q. ilex extract was prepared by heating in water at 90°C and then characterized by mass spectrometry. Phenolic compounds from this extract were administered in drinking water to female mice in three different concentrations (0.03, 0.06, and 0.09 g/mL) over a period of 28 consecutive days. Six groups (n = 6) were formed for this study: group 1 (G1, wildtype [WT], water), group 2 (G2, HPV, water), group 3 (G3, WT, 0.09 g/mL), group 4 (G4, HPV, 0.03 g/mL), group 5 (G5, HPV, 0.06 g/ mL), and group 6 (G6, HPV, 0.09 g/mL). Throughout the experiment, humane endpoints, body weight, food intake, and water consumption were recorded weekly. Following the experimental period, all mice were sacrificed, and blood, internal organs, and skin samples were collected. Blood was used to measure glucose and microhematocrit and later biochemical parameters, such as creatinine, urea, albumin, alanine aminotransferase, and total proteins. Histological analysis was performed on skin and organ samples. Results: The administration of Q. ilex extract resulted in a statistically significant increase in relative organ weight among HPV transgenic animals, indicating adaptive biological response to the tested concentrations. Moreover, a reduction in characteristic skin lesions was observed in animals treated with the 0.06 and 0.09 g/mL extract. Conclusion: These results provide a favorable chemopreventive profile for Q. ilex extract at concentrations of 0.06 and 0.09 g/mL. This study highlights the potential of Q. ilex extract as a safe and effective therapeutic strategy against HPV16- associated lesions in transgenic mouse models. The limitation of our study was the durability of transgenic animals. As a more sensitive species, we must always be careful with the durability of the test. We intend to study concentrations of 0.06 and 0.09 g/mL for longer to further investigate their possible effects.
- Urinary bladder cancer - Old models, new opportunitiesPublication . Oliveira, PA; Vala, Helena; Gil da Costa, RM; Pinto-Leite, MR; Arantes-Rodrigues, R; Vasconcelos-Nóbrega, CUrinary bladder cancer remains as one of most frequent tumours. To elucidate the reasons for the development of tumours, to find out which factors determine the tumour progression and to develop new and better treatments with fewer side effects, intensive research, with the combination of in vitro and in vivo studies is mandatory. So, in this manuscript we performed a revision concerning the different methodologies to study this disease. In authors’ opinion, the best strategy to improve scientific knowledge for UBC should always rely in the association of in vivo and in vitro results. Currently, there are still many challenges in UBC diagnosis and therapy. These challenges must be faced as new opportunities. The molecular diagnostics and genomic revolution will be fundamental to develop new therapeutic modalities, and also to promote personalized therapies.
- Produção de aves em modo biológico: uma estratégia sustentávelPublication . Coelho, Catarina; Costa, Cristina Amaro Da; Oliveira, Jorge
- Histopathological features of organs in a rat model of mamamry carcinogenesis: a reference databasePublication . Vala, Helena; Nóbrega, Carmen; Gama, Adelina; Ferreira, Rita; Oliveira, Paula A.; Faustino-Rocha, Ana I.Mammary tumors’ development was induced through the intraperioneal administration of the carcinogen N-methyl-N-nitrosourea (MNU). Animals from group control were injected with the vehicle (saline solution). Animals were sacrificed at 25 weeks-old and the organs were histopathologically evaluated. A higher number of lesions was observed in the organs of animals from group MNU. The animals from group control did not present any lesion in lymph nodes. Independently of the experimental group, the internal organs presented hemodynamic alterations, degenerative and inflammatory changes. Hemodynamic changes may be consequence of euthanasia method. As expected, the higher number and the higher grade of the lesions in group MNU were due to the carcinogen administration.
- Mortality and Morbidity of Beef Calves in Free-Range Farms in Alentejo, Portugal—A Preliminary StudyPublication . Santos, Rute; Cachapa, Ana; Carvalho, Graça P.; Silva, Carolina B.; Hernández, Laura; Costa, Lina; Pereira, Luísa S.; Minas, Miguel; H, ValaExtensive cow-calf beef cattle farms play a significant role in Portuguese livestock production, but records of important production variables, such as calf mortality, are scarce. To assess herd-level calf mortality and its potential economic impact, farmers from the Alentejo region were asked to fill a questionnaire regarding herd size, feeding and reproductive management practices, calf mortality (from birth to weaning), and detection of the main morbidity causes, as well as of sudden, unexplained deaths during the previous 12 months. Farmers were also requested to quantitatively assess the economic impact of calf mortality on their annual revenue. In the majority of farms, the herd size was larger than 100 animals. The median stocking rate was 0.41 adult animals/hectare, and 70% of farmers stated their farm was self-sufficient in forage. The percent of live births that resulted in weaned calves averaged 94.3%, which led to the assumption of a 5.7% calf mortality rate from birth to weaning. In the previous 12 months, 78.8% of the farms identified at least one case of calf diarrhea, 60.7% identified at least one case of respiratory disease, and 82.1% had at least one sudden, unexplained calf death. As expected, farmers that assessed a higher impact of calf losses on their annual economic revenue were also those who reported higher incidences of calf diarrhea, respiratory disease, and sudden, unexplained deaths. One-quarter of the farmers were unable to assess the economic impact of calf mortality on the farm’s revenue. Herd size appears to have a predictive value on calf mortality in the first month of life, and from 30 days to weaning. The number of sudden, unexplained calf deaths seems to have a predictive value on overall calf mortality (from birth to weaning), suggesting that the farms’ management practices probably play an important role in calf mortality throughout the suckling period. Further studies are needed to fully understand calf mortality in Portuguese extensive rearing systems.
- Prospective Serosurvey of Coxiella burnetii Antibodies in Selected Sheep of PortugalPublication . Cruz, Rita; Esteves, Fernando; Vasconcelos-Nóbrega, Carmen; Santos, Carla; Ferreira, Ana Sofia; Mega, Cristina; Coelho, Ana Claudia; H, Vala; Mesquita, JoãoQ fever is a zoonotic disease caused by Coxiella burnetii that is highly prevalent across the world. In this study, a prospective serosurvey was performed to study C. burnetii circulation in a population of sheep in the central region of Portugal. Blood from a representative sample of 168 animals was drawn in both 2015 and 2016, and sera were tested for IgG anti-C. burnetii by EIA. In 2015, 7.7% (13/168) animals tested positive for IgG anti-C. burnetii, while in 2016, 17.3% (29/168) tested positive, showing a statistically significant (P = 0.008) increase in anti-C. burnetii seroprevalence. Results support the notion that Q fever is emerging in central Portugal.
- Renal risk-benefit determinants of recombinant human erythropoietin therapy in the remnant kidney rat model - hypertension, anaemia, inflammation and drug dose.Publication . Ribeiro, Sandra; Garrido, Patrícia; Fernandes, João; Vala, Helena; Rocha-Pereira, Petronila; Costa, Elísio; Belo, Luís; Reis, Flávio; Santos-Silva, AliceClinical studies showed that high doses of recombinant human erythropoietin (rHuEPO) used to correct anaemia in chronic kidney disease (CKD) hyporesponsive patients may lead to deleterious effects. The aim of this study was to analyze the effects of rHuEPO in doses usually used to correct CKD-anaemia (100, 200 IU/kg body weight (BW) per week) and in higher doses used in the treatment of hyporesponsive patients (400, 600 IU/kg BW per week), focusing on renal damage, hypoxia, inflammation and fibrosis. Male Wistar rats with chronic renal failure (CRF) induced by 5/6 nephrectomy were treated with rHuEPO or with vehicle, over a 3-week period. Haematological, biochemical and renal function analyses were performed. Kidney and liver mRNA levels were evaluated by quantitative real-time polymerase chain reaction (qPCR) and protein expression by Western blot and immunohistochemistry. Kidney histopathological evaluations were also performed. The CRF group developed anaemia, hypertension and a high score of renal histopathologic lesions. Correction of anaemia was achieved with all rHuEPO doses, with improvement in hypertension, renal function and renal lesions. In addition, the higher rHuEPO doses also improved inflammation. Blood pressure was reduced in all rHuEPOtreated groups, compared to the CRF group, but increased in a dose-dependent manner. The current study showed that rHuEPO treatment corrected anaemia and improved urinary albumin excretion, particularly at lower doses. In addition, it is suggested that a short-term treatment with high doses, used to overcome an episode of hyporesponsiveness to rHuEPO therapy, can present benefits by reducing inflammation, without worsening of renal lesions; however, the pro-hypertensive effect should be considered, and carefully managed to avoid a negative cardiorenal impact.
- Serologic evidence for Schmallenberg virus circulation at high altitude, Central Portugal, 2015-2016Publication . Esteves, F.; Cruz, R.; Vasconcelos-Nóbrega, C.; Santos, C.; Ferreira, A. S.; Petrovic, T.; Cardoso, L.; H , Vala; Coelho, Ana; Mesquita, JoãoA few years after the initial 2011 large scale Schmallenberg virus (SBV) epidemic that affected Europe, a subsequent decrease in new SBV infections was observed presumably associated with natural substitution of previously exposed animals. In the present work, a 2-year prospective serosurvey was performed to evaluate SBV circulation in a population of sheep living at high altitude in the central region of Portugal and with restricted movement. Blood from a representative sample of 168 autochthonous sheep was collected in 2015 and again in 2016, and tested for the presence of anti-SBV IgG by ELISA. Of the 2015 sample collection, seven animals tested positive for anti-SBV IgG, corresponding to a seroprevalence of 4.2% while of the 2016 sample collection, 10 presented SBV antibodies, showing a seroprevalence of 6.0% (p = 0.619). Results show that SBV is endemic in sheep of central Portugal, even in herds at high altitude locations. When comparing anti-SBV seroprevalences of 2015/2016 found in this study, to one detected in 2014 in the same region, a steep decrease could be observed (p < 0.001). This is in accordance with what has been documented in Western European countries, where a decrease in the number of SBV-infected sheep has been found, a fact which may pose a new threat for SBV re-emergence.
- Outbreaks of abortions byCoxiella burnetiiin small ruminant flocks and a longitudinal serological approach on archived bulk tank milk suggest Q fever emergence in Central PortugalPublication . Cruz, Rita; Esteves, Fernando; Vasconcelos-Nóbrega, Carmen; Santos, Carla; Ferreira, Ana S.; Mega, Cristina; Coelho, Ana C.; H, Vala; Mesquita, João R.Q fever is a worldwide zoonotic infectious disease caused by Coxiella burnetii and sheep and goats are known to be the main reservoir for human infection. This study describes the epidemiological and laboratory findings of C. burnetii outbreaks affecting sheep and goat flocks and also provides the results of a prospective serosurvey in bulk tank milk samples to assess C. burnetii circulation in a population of sheep living in close contact to the human population in Central Portugal. In the epizooties, C. burnetii was identified in tissues of the resulting abortions by qPCR. As for the serological survey, 10.2% (95%CI: 4.5‐19.2) of the 78 bulk tank milk samples collected in 2015 presented IgG antibodies against C. burnetii. The same farms were visited and sampled in 2016 and 25.6% (95%CI: 16.4‐36.8) were positive. This steep increase in the number of anti‐C. burnetii farms between the 2015 and 2016 collections showed to be statistically significant (p = 0.020) and is strongly suggestive of Q fever emergence in Central Portugal. Measures on animal health and on disease spread control to the human population should be considered.
- Assessment of ammonia and carbon dioxide concentrations in a breeding hen building under Portuguese winterPublication . Pereira, José Luís; Ferreira, Sílvia; Garcia, Carla; Conde, André; Ferreira, Pedro; Pinheiro, Victor; Trindade, HenriqueExcessive ammonia (NH3) and carbon dioxide (CO2) in the housing of breeding hens can cause various negative effects on the health of hens and the welfare of the workers who care for them. The aim of this study was to evaluate the NH3 and CO2 concentrations in the first month of housing the breeding hens during Portuguese winter. The study was conducted on a commercial hen breeding farm located in central Portugal. One modern building equipped with climate control system, automatic feeding and drinking systems and minimum transitional tunnel ridge system was selected. New litter material made with rice hulls was used in the building, and the breeding sample comprised five months old 6864 female and 720 male birds housed in the building on 7 November 2016. The outdoor and indoor environmental conditions and indoor gas concentrations were measured continuously from 10 November to 30 November 2016. (NH3)and CO2 concentrations were measured with a photoacoustic field gas monitor and air samples collected through 4 sampling points located indoor, by a multipoint sampler. Results showed that the CO2 concentrations did not exceed 3000 ppm during the first month of housing the breeding hens and under winter environment. However, the NH3 concentrations exceed 20 ppm on most measurement days. For a good indoor air quality, the study suggests the use of mitigating measures for maintaining NH3 concentration below 10 ppm.