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  • New therapeutic approaches on chronic kidney disease
    Publication . Nogueira, A.; Vala, Helena; Nóbrega, Carmen; Pires, C. A.; Colaço, B.; Oliveira, P. A.; Pires, M. J.
    Introduction: chronic kidney disease is a serious public health problem that affects millions of patients worldwide. So, the main research goals in the CKD patients are the research of new therapeutic approaches capable of slowing down the progression to end-stage renal disease. Objective: the aim of this work, was to evaluate the effects of chronic administration of chaetomellic acid A (CAA), which selectively blocks H-Ras farnesylation, on kidney chronic lesions in 5/6 nephrectomized Wistar rats, an animal model of chronic renal disease. Material and methods: sixty male Wistar rats (Rattus norvergicus) were housed under controlled conditions. After seven weeks of acclimatization, rats (weighing 359 to 402 g) were sham-operated (SO) or submitted to 5/6 nephrectomy (RMR). One week after surgery surviving animals (n=53) were distributed into four groups: SO: SO rats receiving no treatment (n=13); SO+CAA: SO rats receiving CAA treatment (n=13); RMR: RMR rats receiving no treatment (n=14); RMR+CAA: RMR rats receiving CAA treatment (n=13). CAA was intraperitoneally administered (0.23 µg/Kg) three times a week for six months. Six months after the surgical procedure, in the left kidney of each animal was evaluated the mean cortical and medullary echogenicity by two-dimensional ultrasonography. Then, the kidneys were removed, fixed in 10% neutral-buffered formalin and processed for routine histopathological diagnosis and chronic lesions were evaluated, by Hematoxylin-Eosin, reticulin and Masson trichrome methods, for severity. All experimental procedures followed the European (European Directive 2010/63/EU) and National (Decree-Law 113/2013) legislation on the protection of the animals used for scientific purposes. Results: the kidneys of the RMR animals treated with CAA showed a significantly decrease in the medullary echogenicity (p<0.05) compared with the RMR rats that received no treatment. Glomerulosclerosis and arteriolosclerosis scores were significantly lower (p<0.001) in the RMR+CAA group when compared with the RMR group. There were no significant differences in interstitial fibrosis, interstitial inflammation and tubular dilatation scores between the RMR+CAA and RMR groups.Conclusion: this data suggests that pharmacological inhibition of H-Ras proteins activation may be a future strategy in the prevention of end-stage renal disease.
  • A Nationwide Seroepidemiologic Study on Q Fever Antibodies in Sheep of Portugal
    Publication . Cruz, Rita; Esteves, Fernando; Nóbrega, Carmen; Santos, Carla; Ferreira, Ana S.; Mega, Cristina; Coelho, Ana C.; Vala, Helena; Mesquita, João
    Introduction: Q fever is an almost global zoonotic disease caused by Coxiella burnetii. Human infections can produce acute and chronic disease that can lead to abortions and stillbirths in pregnant women, usually infected by the inhalation of C. burnetii-contaminated aerosols or through consumption of contaminated products. Sheep are one of the primary animal reservoirs with disease being associated with vast shedding of bacteria in placentas, feces, milk, and birth fluids. Although almost neglected in the past, recent outbreaks of sheep origin have alerted the public and the scientific community. Materials and Methods: An epidemiologic survey to estimate the seroprevalence of Q fever antibodies was performed in a representative number of sheep of all regions of continental Portugal (n = 1068), using a commercial ELISA (ID Screen Q Fever Indirect Multi-species Kit; IDvet, Montpellier, France). Results and Discussion: An anti-C. burnetii seroprevalence of 11.4% (95% confidence interval 9.6–13.5) was found, with a clear distinction between the Center region with highest seroprevalence, and the rest of the territory. Sheep traditional farming is widely present in Portugal and is part of the cultural and gastronomical background of the country. This close proximity to small ruminants may contribute to the zoonotic transfer to humans.
  • Exploring the therapeutic potential of Quercus ilex acorn extract in papillomavirus-induced lesions
    Publication . 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.
  • A 2-Year Longitudinal Seroepidemiological Evaluation of Toxoplasma gondii Antibodies in a Cohort of Autochthonous Sheep from Central Portugal
    Publication . Almeida, Daniela; Quirino, João; Barradas, Patrícia Ferreira; da Silva, Priscilla Gomes; Pereira, Maria; Cruz, Rita; Santos, Carla; Mega, Cristina; Esteves, Fernando; Nóbrega, Carmen; Vala, Helena; Gärtner, Fátima; Amorim, Irina; Mesquita, João R.
    Background: Toxoplasma gondii is an important zoonosis and one of the major causes of abortion in sheep worldwide. (2) Methods: We performed a 2-year longitudinal serological antiT. gondii IgG screening on a cohort of a spatially confined population of a Portuguese autochthonous sheep breed in central Portugal. (3) Results: From the screening of the 2015 and 2016 sera, an increase of seroprevalence was observed (57.7% (95% CI: 49.9–65.3%) versus 69.1% (95% CI: 61.5–75.9), from 2015 and 2016, respectively) (p = 0.031). (4) Conclusions The present study is the first to provide prospective data on the anti-T. gondii serological status of a sheep cohort in Portugal, showing an increase in the occurrence of T. gondii. There is a need to provide a clearer understanding of T. gondii epidemiology in Portugal, ideally by implementing monitoring programs on sentinel herds, not only due to the high impact of T. gondii on animal health but also for it being a zoonosis.
  • Cuidados paliativos em oncologia veterinária
    Publication . Garcia, Ana; Mesquita, João; Nóbrega, Carmen; Vala, Helena
    A incidência de lesões oncológicas em animais de companhia tem vindo a aumentar nos últimos anos. Este aumento ocorre devido a um variado número de razões, sendo uma das principais a actual maior longevidade dos animais de companhia (Withrow, 2001). Apesar da evolução que a oncologia veterinária tem sofrido nos últimos tempos, sabemos que, aproximadamente metade dos pacientes oncológicos, acabará por ser vitimada por esta doença e, a maior parte, necessitará de terapia para controlo da sintomatologia e da dor (Page, 2001). Tal como no homem, um animal com doença oncológica não sofre apenas com o tumor e a sua localização, mas também com vários problemas subjacentes, designadamente as síndromes paraneoplásicas. Estas síndromes são alterações induzidas pelo tumor e provocam efeitos sistémicos significativos, conduzindo a uma redução da condição geral do paciente (Simon, 2006). A caquéxia é a síndrome paraneoplásica mais comum em oncologia veterinária (Robinson & Ogilvie, 2001; Wakshlag & Kallfelz, 2006). O cuidado compassivo do animal, actualmente relevado por uma extrema manifestação de carinho, com recurso aos conhecimentos científicos mais modernos, é um dos novos desafios da Enfermagem e da Medicina Veterinária, assumindo importância crescente em todas as fases de tratamento de pacientes oncológicos. Este tipo de cuidados surge como uma reposta directa ao reconhecimento da evolução que a relação entre o animal e o proprietário tem sofrido ao longo dos últimos anos (Ogilvie, 2003). Os avanços na área de saúde veterinária, aliados ao desenvolvimento de centros de tratamento avançado, resultaram na capacidade de tratar, cada vez melhor, os animais de companhia. O desenvolvimento da área dos cuidados paliativos pressupõe o reconhecimento de que cada doente pode ser ajudado, independentemente de problemas financeiros, do tempo e do diagnóstico subjacente, recorrendo a terapias de suporte, tratamento curativo ou terapia paliativa (Ogilvie, 2003). A manutenção da qualidade de vida dos animais é o principal objectivo deste tipo de cuidados (Page, 2001; Ogilvie, 2003; Simon, 2006).
  • Crimean-Congo hemorrhagic fever virus circulating among sheep of Portugal: a nationwide serosurvey assessment
    Publication . Mesquita, João; Cruz, Rita; Esteves, Fernando; Santos, Carla; Pousa, Humberto; Coelho, Catarina; Mega, Cristina; Nóbrega, Carmen; Vala, Helena; Peyrefitte, Christophe Nicolas; Nascimento, Maria São José; Barradas, Patrícia Ferreira
    Crimean-Congo hemorrhagic fever virus (CCHFV) is a widespread zoonotic pathogen that can cause mild to severe hemorrhagic disease in humans. CCHFV may be transmitted through direct contact with tissue or blood of viremic animals; however, the primary transmission route is through infected tick bites. CCHFV RNA has been detected in ticks feeding on domestic and wild animals in western Spain, suggesting an established circulation of CCHFV in Western Europe. Ruminants have been recognized as important CCHFV reservoirs and have been linked to human cases in endemic regions. Given the emergence of CCHF in neighboring Spain, and a report of two CCHFV seropositive humans in southern Portugal in 1985, we investigated the potential circulation of this virus in the country by performing a nationwide anti-CCHFV IgG serosurvey in sentinel sheep of Portugal. Sera (n = 459) randomly selected from widely distributed farms (n = 20) of Portugal were tested using a commercial double-antigen enzyme-linked immunosorbent assay, yielding an overall seroprevalence of 0.4% (95% confidence interval [CI] 0.04-1.56%). Positive sheep were from the southern region of Portugal (Alentejo region), which raise the seroprevalence of this region to 0.74% (95% CI 0.09-2.66%). This is the first study reporting the presence of CCHFV antibodies in sheep of Portugal, thus suggesting a geographical expansion of CCHFV to this country. It seems likely that CCHFV may exist focally in southern Portugal.
  • A case of vascular tumour mimicking lymphangioma
    Publication . Vala, Helena; Mega, Cristina; Santos, C.; Cruz, Rita; Santos, M.; Esteves, Fernando; Nóbrega, Carmen; Mesquita, João
    Introduction Sarcomas, particularly vascular tumours, can mimic other neoplastic conditions or even inflammatory diseases. Objectives The authors describe an unusual case of vascular tumour, histologically overlapping with benign lymphangioma and liposarcoma. Medical History A 8 year old Shar Pei male dog was presented with a subcutaneous nodule in the chest, measuring 3x2 cm. Material and Methods The sample was fixed in 10 % buffered formalin solution and processed for routine histopathological diagnosis with Haematoxylin and Eosin. A standard Streptavidin-Biotin Complex technique for immunohistochemical evaluation was also performed, using a Polyclonal Rabbit Anti-Human Von Willebrand Factor. Results Macroscopic examination revealed a well circumscribed nodule with homogeneous and brownish appearance and moderate consistency on a cut surface. Microscopic examination revealed clefts and variably-sized vascular spaces, lined by a single layer of spindle cells, with round-to-oval nuclei, small or indistinct nucleoli, small amount of eosinophilic cytoplasm, with endothelial appearance – areas like hemangiosarcoma, interspersed with areas, where these cells appeared to grow directly on thick bundles of dermal collagen, occasionally with erythrocytes – areas like lymphangioma. The stroma was also interspersed with vacuolar cells – areas like liposarcoma. No mitotic figures were seen, however, the presence of very rich cellular areas, with more prominent cells revealing pleomorphism and anisocariosis, were more favour to malignancy Conclusion The authors suggested the diagnosis of vascular neoplasia with unusual features, based on the histopathological diagnosis and immunohistochemistry results, and submit to the discussion, especially for assessment of histological grade and prognosis.
  • Pulmonary and Gastrointestinal Parasitic Infections in Small Ruminant Autochthonous Breeds from Centre Region of Portugal—A Cross Sectional Study
    Publication . Pereira, Maria; Vila-Viçosa, Maria; Coelho, Catarina; Santos, Carla; Esteves, Fernando; Cruz, Rita; Gomes, Liliana; Henriques, Diogo; Vala, Helena; Nóbrega, Carmen; Mega, Cristina; Melo, Carolina de; Malva, Madalena; Braguez, Joana; Mateus, Teresa Letra
    The production of small ruminant autochthonous breeds in the Centre region of Portugal is practiced in a semi-extensive husbandry system, exposing animals to parasitic infections. The main objective of this study was to estimate the prevalence of lungworm infection and identify risk factors. Fecal samples of 203 goats and 208 sheep from 30 herds were collected per rectum and subjected to the modified Baermann test. The overall prevalence of infection was 57.7%, significantly higher in goats (95.6%) than in sheep (20.7%) (p < 0.001). According to the binary logistic regression model, sheep dewormed with albendazole, mebendazole plus closantel, or ivermectin plus clorsulon presented a risk of Protostrongylidae infection 29.702, 7.426, or 8.720 times higher, respectively, than those dewormed with eprinomectin. Additionally, the presence of gastrointestinal parasites was investigated in 307 fecal samples using Mini-FLOTAC®. The overall prevalence of infection was 86.3%, also significantly higher in goats (93.2%) than in sheep (79.9%) (p < 0.001). Strongyle-type eggs were the most frequently identified, both in sheep (69.8%) and goats (87.8%), followed by Eimeria oocysts (40.3% in sheep and 68.9% in goats). Considering the high prevalence and the burden of lungworm parasitic infection, it is urgent to determine its economic impact and the repercussions in animal health in the Centre region of Portugal to establish appropriate therapeutic guidelines.
  • An Antibody-Based Survey of Toxoplasma gondii and Neospora caninum Infection in Client-Owned Cats from Portugal
    Publication . Pereira, Maria Aires; Nóbrega, Carmen; Mateus, Teresa Letra; Almeida, Daniela Gomes de; Oliveira, Andreia; Coelho, Catarina; Cruz, Rita; Oliveira, Paula; Faustino-Rocha, Ana; Pires, Maria J.; Mesquita, João R.; Vala, Helena
    Toxoplasma gondii and Neospora caninum are obligate intracellular protozoan parasites infecting a wide range of hosts worldwide. However, information on the epidemiology of toxoplasmosis and neosporosis in cats from Portugal is limited. Thus, this study aims to evaluate anti-T. gondii and anti-N. caninum seroprevalence in client-owned cats from Portugal and to identify risk factors using a panel of well-characterized sera. A total of 183 domestic cats were sampled and screened for antibodies against T. gondii and N. caninum using commercial ELISA assays, and their owners answered an online questionnaire designed to obtain background information. The overall anti-T. gondii and anti-N. caninum seroprevalences were 13.1% (CI: 8.97–18.77) and 3.8% (CI: 1.87–7.68), respectively. Univariate analysis revealed that living strictly indoors was a significant protection factor (cOR: 0.053; CI: 0.005–0.627), and the presence of a chronic disease a significant risk factor (cOR: 3.106; CI: 1.062–9.082) to T. gondii seroprevalence. When performing multivariate analysis, only chronic disease (aOR: 57.527; CI: 1.7–1976.7) and seropositivity to N. caninum (aOR: 7.929; CI:0.8–82.9) were found to be a significant risk factor to anti-T. gondii antibodies. To the best of our knowledge, this is the first report of N. caninum seropositivity in cats from Portugal.
  • Epidemiology and Emergence of Schmallenberg Virus Part 1: Origin, Transmission and Differential Diagnosis
    Publication . Esteves, Fernando; Mesquita, João; Nóbrega, Carmen; Santos, Carla; Monteiro, António; Cruz, Rita; Vala, Helena; Coelho, Ana Cláudia
    Schmallenberg virus (SBV) is a novel Orthobunyavirus causing mild clinical signs in cows and malformations in aborted and neonatal ruminants in Europe. SBV belongs to the family Bunyaviridae and is transmitted by biting midges. This new virus was identified for the first time in the blood samples of cows in the city of Schmallenberg in NorthRhine-Westphalia in November 2011. Since then the virus spread to several European countries. Here we describe the origin and emergence, as well as the transmission and the differential diagnosis of this virus, now known to be a serious threat to Veterinary Public Health.