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Featured researches published by João Machado.


Parasites & Vectors | 2010

Canine babesiosis in northern Portugal and molecular characterization of vector-borne co-infections.

Luís Cardoso; Yael Yisaschar-Mekuzas; Filipa T Rodrigues; Álvaro Costa; João Machado; Duarte Diz-Lopes; Gad Baneth

BackgroundProtozoa and bacteria transmitted by arthropods, including ticks and phlebotomine sand flies, may cause a wide range of canine vector-borne diseases. Dogs can be simultaneously or sequentially infected with multiple pathogens. Canine babesiosis caused by Babesia canis canis and Babesia canis vogeli is known to occur in Portugal. This study assessed, by means of blood smear examination, PCR and DNA nucleotide sequencing, the presence of Babesia spp. and co-infecting agents Leishmania, Anaplasma/Ehrlichia and Hepatozoon in 45 dogs from northern Portugal clinically suspected of babesiosis.ResultsForty-four dogs (98%) had infection with B. canis canis and one with B. canis vogeli. Co-infections were detected in nine animals (20%). Eight dogs were found infected with two vector-borne agents: six with B. canis canis and Leishmania infantum; one with B. canis canis and Ehrlichia canis; and one with B. canis canis and Hepatozoon canis. Another dog was infected with three vector-borne pathogens: B. canis vogeli, E. canis and L. infantum. Overall, L. infantum was found in seven (16%), E. canis in two (4%), and H. canis in one (2%) out of the 45 dogs with babesiosis. Almost 90% of the 45 cases of canine babesiosis were diagnosed in the colder months of October (18%), November (27%), December (20%), February (13%) and March (9%). Co-infections were detected in February, March, April, May, October and November. Twenty-two (50%) out of 44 dogs infected with B. canis were found infested by ticks including Dermacentor spp., Ixodes spp. and Rhipicephalus sanguineus. Mortality (9%) included two co-infected dogs that died spontaneously and two with single infections that were euthanized.ConclusionsBabesia canis canis is the main etiological agent of canine babesiosis in northern Portugal. A higher sensitivity of Babesia spp. detection was obtained with PCR assays, compared to the observation of blood smears. Twenty percent of the dogs were co-infected with L. infantum, E. canis or H. canis. Furthermore, this is the first molecular identification of H. canis in dogs from northern Portugal.


Parasites & Vectors | 2012

First report of canine ocular thelaziosis by Thelazia callipaeda in Portugal

Lisete Vieira; Filipa T Rodrigues; Álvaro Costa; Duarte Diz-Lopes; João Machado; Teresa Coutinho; Joana Tuna; Maria Stefania Latrofa; Luís Cardoso; Domenico Otranto

BackgroundThelazia callipaeda eyeworms are transmitted by the non-biting insect vector Phortica variegata in Europe and infest the conjunctiva(s) of several mammalians, including dogs and humans. Infested hosts might remain asymptomatic or display clinical manifestations characterized by variable degrees of severity.MethodsFrom July to November 2011, nine dogs were detected with eyeworms at two veterinary clinics in Chaves and Bragança (North of Portugal). Nematodes collected from dogs were morphologically and molecularly characterized at species level.ResultsNematodes were identified as T. callipaeda. The number of worms collected from each dog ranged from three to 76 (average = 17.9 ± 26.8) and was not associated with the severity of clinical signs. Ocular discharge and conjunctivitis were observed in all dogs and ocular pruritus occurred in six of them. Polymerase chain reaction and sequencing of a portion of target cytochrome c oxidase subunit 1 gene further identified all nematodes as haplotype 1.ConclusionsThis is the first report of T. callipaeda and associated ocular disease in dogs from Portugal, suggesting that thelaziosis should be included in the differential diagnosis of canine ocular affections. The risk of the infestation spreading from Spain and France to Portugal, through domestic dogs or wild mammals, is realistic.


Molecular Biology Reports | 2013

Interleukin-6 gene −174G>C and −636G>C promoter polymorphisms and prostate cancer risk

J. F. Magalhães; António Cortinhas; Carlos Albuquerque; Cláudia S. Baptista; R. Ribeiro; Carlos Viegas; A.J.F. Matos; João Machado; M.A. Pires; Henrique Guedes-Pinto; A. Martins-Bessa; José Carlos Leitão; Estela Bastos

Prostate cancer (PCa) is one of the most commonly diagnosed internal malignancies affecting men. Due to the important roles of IL-6 in different physiological and pathophysiological processes, IL-6 polymorphisms may modulate PCa risk. IL-6 −174 G>C (rs 1800795, also designated −236 G>C) and −636 G>C (rs 1800796, also designated −572 G>C) promoter polymorphisms have been implicated in PCa susceptibility, albeit still controversial. A literature search using PubMed and Highwire databases was conducted, resulting in eight case–control studies concerning the IL-6 −174 G>C polymorphism (11,613 PCa cases and 13,992 controls) and four case–control publications regarding the IL-6 −636 G>C polymorphism (1,941 PCa cases and 3,357 controls). In order to derive a more precise estimation, a meta-analysis based upon these selected case–control studies was performed. There was no significant association between IL-6 −174 G>C polymorphism and PCa increased risk. Nevertheless, the presence of allele C and the CC genotype were statistically significantly associated with decreased PCa risk in the overall analysis for IL-6 −636 G>C polymorphism. Additional studies in larger samples and analyses of functional repercussions of these SNPs in prostate tumor cells are necessary to validate these findings.


Parasites & Vectors | 2012

Tongue nodules in canine leishmaniosis--a case report.

Carlos Viegas; João Filipe Requicha; Carlos Albuquerque; Teresa Sargo; João Machado; Isabel R. Dias; Maria A. F. Pires; Lenea Campino; Luís Cardoso

BackgroundCanine leishmaniosis (CanL) caused by Leishmania infantum is an endemic zoonosis in southern European countries. Infected dogs can present rare or atypical forms of the disease and diagnosis can be challenging. The present report describes a case of tongue nodules in a 3-year-old neutered female Labrador Retriever dog with leishmaniosis.FindingsA fine needle aspiration of the lingual nodules revealed amastigote forms of Leishmania inside macrophages. Differential diagnosis ruled out neoplasia, calcinosis circumscripta, solar glossitis, vasculitis, amyloidosis, eosinophilic granulomas, chemical and electrical burns, uremic glossitis and autoimmune diseases. Combined therapy with antimoniate meglumine and allopurinol for 30 days resulted in the normalization of hematological and biochemical parameters. Two months after diagnosis and the beginning of treatment, a mild inflammatory infiltrate was observed by histopathology, but an anti-Leishmania immunofluorescence antibody test (IFAT) was negative as well as a PCR on both tongue lesions and a bone marrow aspirate. Seven months after diagnosis, the dog’s general condition appeared good, there were no tongue lesions and a new IFAT was negative. Fifteen months after diagnosis this clinically favourable outcome continued.ConclusionsThe dog could have suffered a relapsing episode of CanL, but a new systemic or local infection cannot be excluded. Regular clinical re-evaluation should be maintained, as a future relapse can potentially occur. In conclusion, CanL should be considered in the differential diagnosis of nodular glossitis in dogs.


GE Portuguese Journal of Gastroenterology | 2015

Disability in Inflammatory Bowel Disease: Translation to Portuguese and Validation of the ''Inflammatory Bowel Disease --- Disability Score''

Joana Magalhães; Francisca Dias de Castro; Pedro Boal Carvalho; João Machado; Sílvia Leite; Maria João Moreira; José Cotter

Background Inflammatory bowel disease (IBD) has a physical, psychological and social impact, often compromising the patients ability to perform daily activities. Recently a new measurement for disability in IBD was developed. The Inflammatory Bowel Disease-Disability Score (IBD-DS) comprises the following domains: mobility, self-care, major daily life activities, gastrointestinal-related problems, mental health and interaction with the environment. The aim of our study was to translate to Portuguese and to validate the IBD-DS. Methods Eighty-five patients, 55 with Crohns disease (CD) and 30 with ulcerative colitis (UC), completed the Portuguese version of the IBD-DS and the short inflammatory bowel disease questionnaire (SIBDQ-10 questions). Disease activity was assessed using the Harvey–Bradshaw (HB) for CD and partial Mayo score (pMayo) for UC. Pearsons correlation coefficient was used to assess the correlation between the IBD-DS and SIBDQ. The Students t-test was used to compare the mean of IBD-DS between active and inactive disease. Statistical analysis was performed with SPSS 21.0 and the statistical level of significance (α) was established at 5%. Results In our study, a significant negative correlation between the IBD-DS and the SIBDQ was observed (r = −0.858, p < 0.001 for CD and r = −0.933, p < 0.001 for UC). There was a statistically significant difference of the mean of IBD-DS between inactive vs. active disease (93.78 vs. 117.57, p = 0.016 for CD and 78.96 vs. 137.14, p < 0.001 for UC). Conclusion The Portuguese version of the inflammatory bowel disease-disability score has a strong correlation with patients’ quality of life and clinical disease activity and was shown to be a valid tool to measure disability in patients with inflammatory bowel disease.


Reproduction in Domestic Animals | 2008

Priapism Secondary to Perineal Abscess in a Dog – A Case Report

A. Martins-Bessa; T Santos; João Machado; R Pinelas; M.A. Pires; Rita Payan-Carreira

A 7-year-old intact male Boxer was referred to our services at the Veterinary Teaching Hospital of the University of Trás-os-Montes and Alto Douro, suffering from a persistently erect penis (including the bulbus glandis) that had been exposed for several days. Radiographic and ultrasonographic examinations detected a 5.0 x 3.5 cm mass located dorso-laterally to the urinary bladder. The microbial culture of the mass revealed Staphylococcus spp. At that time, we suspected the involvement of an abscess in the origin of the priapism. Medical and surgical treatments were promptly instituted, which allowed for penile withdrawal into the prepuce; however, the resolution of the penile erection was not accomplished in the following days and penile amputation was required. Histological evaluation of the excised penis revealed extensive infarction of the erectile tissue of the pars longa and bulbus glandis, and also of the blood vessels of the penis. Following penile amputation and antimicrobial therapy, the animal fully recovered. Ultimately, the animal died as a consequence of gastric torsion. At necropsy, some lesions compatible with a previous perforation of the intestinal wall were recorded. The data gathered from the anamnesis, the physical and imaging examinations, along with the post-mortem findings, allowed us to conclude that in this clinical case the primary cause of priapism was a perineal abscess due to bowel perforation.


GE Portuguese Journal of Gastroenterology | 2018

Optimizing the Risk Assessment in Upper Gastrointestinal Bleeding: Comparison of 5 Scores Predicting 7 Outcomes

Tiago Cúrdia Gonçalves; Mara Barbosa; Sofia Xavier; Pedro Boal Carvalho; João Machado; Joana Magalhães; Carla Marinho; José Cotter

Introduction: Although different scores have been suggested to predict outcomes in the setting of upper gastrointestinal bleeding (UGIB), few comparative studies between simplified versions of older scores and recent scores have been published. We aimed to evaluate the accuracy of pre- (PreRS) and postendoscopic Rockall scores (PostRS), the Glasgow-Blatchford score (GBS) and its simplified version (sGBS), as well as the AIMS65 score in predicting different clinical outcomes. Methods: In this retrospective study, PreRS, PostRS, GBS, sGBS, and AIMS65 score were calculated, and then, areas under the receiver operating characteristic curve were used to evaluate the performance of each score to predict blood transfusion, endoscopic therapy, surgery, admission to intensive/intermediate care unit, length of hospital stay, as well as 30-day rebleeding or mortality. Results: PreRS, PostRS, GBS, and sGBS were calculated for all the 433 included patients, but AIMS65 calculation was only possible for 315 patients. Only the PreRS and PostRS were able to fairly predict 30-day mortality. The GBS and sGBS were good in predicting blood transfusion and reasonable in predicting surgery. None of the studied scores were good in predicting the need for endoscopic therapy, admission to intensive/intermediate care unit, length of hospital stay, and 30-day rebleeding. Conclusions: Owing to the identified limitations, none of the 5 studied scores could be singly used to predict all the clinically relevant outcomes in the setting of UGIB. The sGBS was as precise as the GBS in predicting blood transfusion and surgery. The PreRS and PostRS were the only scores that could predict 30-day mortality. An algorithm using the PreRS and the sGBS as an initial approach to patients with UGIB is presented and suggested.


GE Portuguese Journal of Gastroenterology | 2017

Acute-on-Chronic Liver Failure: A Portuguese Single-Center Reference Review

Miguel Verdelho; Rui Perdigoto; João Machado; Élia Mateus; Paulo Marcelino; Rui Pereira; Philip Fortuna; Luís Bagulho; Luís Bento; Francisco Ribeiro; Fernando Nolasco; Américo Martins; Eduardo Barroso

Acute-on-chronic liver failure (ACLF) is a syndrome characterized by an acute deterioration of a patient with cirrhosis, frequently associated with multi-organ failure and a high short-term mortality rate. We present a retrospective study that aims to characterize the presentation, evolution, and outcome of patients diagnosed with ACLF at our center over the last 3 years, with a comparative analysis between the group of patients that had ACLF precipitated by infectious insults of bacterial origin and the group of those with ACLF triggered by a nonbacterial infectious insult; the incidence of acute kidney injury and its impact on the prognosis of ACLF was also analyzed. Twenty-nine patients were enrolled, the majority of them being male (89.6%), and the mean age was 53 years. Fourteen patients (48.3%) developed ACLF due to a bacterial infectious event, and 9 of them died (64.2%, overall mortality rate 31%); however, no statistical significance was found (p < 0.7). Of the remaining 15 patients (51.7%) with noninfectious triggers, 11 died (73.3%, overall mortality rate 37.9%); again there was no statistical significance (p < 0.7). Twenty-four patients (83%) developed acute kidney injury (overall mortality rate 65.5%; p < 0.022) at the 28-day and 90-day follow-up. Twelve patients had acute kidney injury requiring renal replacement therapy (41.37%; overall mortality rate 37.9%; p < 0.043). Hepatic transplant was performed in 3 patients, with a 100% survival at the 28-day and 90-day follow-up (p < 0.023). Higher grades of ACLF were associated with increased mortality (p < 0.02; overall mortality 69%). Conclusions: ACLF is a heterogeneous syndrome with a variety of precipitant factors and different grades of extrahepatic involvement. Most cases will have some degree of renal dysfunction, with an increased risk of mortality. Hepatic transplant is an efficient form of therapy for this syndrome.


BMC Veterinary Research | 2017

Evaluation of biomarker canine-prostate specific arginine esterase (CPSE) for the diagnosis of benign prostatic hyperplasia

Dora Pinheiro; João Machado; Carlos Viegas; Cláudia S. Baptista; Estela Bastos; Joana Magalhães; M.A. Pires; Luís Cardoso; Ana Martins-Bessa


Revista Espanola De Enfermedades Digestivas | 2015

Impact of the age of diagnosis on the natural history of ulcerative colitis

Tiago Cúrdia Gonçalves; Francisca Dias de Castro; João Machado; Maria João Moreira; Bruno Rosa; José Cotter

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Luís Cardoso

Instituto de Biologia Molecular e Celular

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M.A. Pires

University of Trás-os-Montes and Alto Douro

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A. Martins-Bessa

University of Trás-os-Montes and Alto Douro

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Carlos Albuquerque

University of Trás-os-Montes and Alto Douro

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Estela Bastos

University of Trás-os-Montes and Alto Douro

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