Pedro Manuel Ferreira

Dr. Pedro Manuel Ferreira

Institute of Hygine and Tropical Medicine – NOVA University, Rua da Junqueira nº 100, 1349-008 Lisbon, Portugal
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Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 November 2017 in International Journal of Infectious Diseases
Verified
Journal Article
Open access
TFTeresa Baptista Fernandes
Teresa Baptista Fernandes
MRManuel Rodrigues
Manuel Rodrigues
ICIsabel Castro
Isabel Castro
PPPaulo Paixão
Paulo Paixão
PPPedro Pinto-Marques
Pedro Pinto-Marques
CTCristina Toscano
Cristina Toscano
Anisakiasis is an emerging marine food-borne zoonosis resulting from the accidental ingestion of Anisakis larvae, through the consumption of raw or undercooked infected seafood products. The first case of human gastric hyperinfection by Anisakis simplex with an unusual and severe presentation, occurring in a Portuguese woman, is described in this article. Over 140 anisakid larvae were removed by gastroscopy. Massive infection is uncommon in areas where the consumption of raw fish is not part of the traditional diet, as is the case in Portugal. The increased consumption of raw seafood products is considered a health determinant in the rise in cases of anisakiasis. However, clinicians should be aware of the emergence of these infections, not only because of the new dietary habits of the population, but also because of the high prevalence of Anisakis larvae in the different fish species usually consumed by the population, collected on the Portuguese coast.

22 November 2016 in PLOS ONE
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Journal Article
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DADaniela De Paula Aguiar
Daniela De Paula Aguiar
MMMayara Brunetto Moreira Moscardini
Mayara Brunetto Moreira Moscardini
EMEnyara Rezende Morais
Enyara Rezende Morais
RPRenato Graciano de Paula
Renato Graciano de Paula
Pedro Manuel FerreiraPedro Manuel Ferreira
Pedro Manuel Ferreira
Lizandra MagalhãesLizandra Magalhães
Lizandra Magalhães
Inducing apoptosis is an interesting therapeutic approach to develop drugs that act against helminthic parasites. Researchers have investigated how curcumin (CUR), a biologically active compound extracted from rhizomes of Curcuma longa, affects Schistosoma mansoni and several cancer cell lines. This study evaluates how CUR influences the induction of apoptosis and oxidative stress in couples of adult S. mansoni worms. CUR decreased the viability of adult worms and killed them. The tegument of the parasite suffered morphological changes, the mitochondria underwent alterations, and chromatin condensed. Different apoptotic parameters were determined in an attempt to understand how CUR affected adult S. mansoni worms. CUR induced DNA damage and fragmentation and increased the expression of SmCASP3/7 transcripts and the activity of Caspase 3 in female and male worms. However, CUR did not intensify the activity of Caspase 8 in female or male worms. Evaluation of the superoxide anion and different antioxidant enzymes helped to explore the mechanism of parasite death further. The level of superoxide anion and the activity of Superoxide Dismutase (SOD) increased, whereas the activity of Glutathione-S-Transferase (GST), Glutathione reductase (GR), and Glutathione peroxidase (GPX) decreased, which culminated in the oxidation of proteins in adult female and male worms incubated with CUR. In conclusion, CUR generated oxidative stress followed by apoptotic-like-events in both adult female and male S. mansoni worms, ultimately killing them.

26 March 2024 in Pathogens
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Journal Article
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Maria Teresa BispoMaria Teresa Bispo
Maria Teresa Bispo
MCMaria Manuela Calado
Maria Manuela Calado
Isabel MauricioIsabel Mauricio
Isabel Mauricio
Pedro Manuel FerreiraPedro Manuel Ferreira
Pedro Manuel Ferreira
Silvana Maria Duarte BeloSilvana Maria Duarte Belo
Silvana Maria Duarte Belo
Cercarial dermatitis (CD), or “Swimmer’s itch” as it is also known, is a waterborne illness caused by a blood fluke from the family Schistosomatidae. It occurs when cercariae of trematode species that do not have humans as their definitive host accidentally penetrate human skin (in an aquatic environment) and trigger allergic symptoms at the site of contact. It is an emerging zoonosis that occurs through water and is often overlooked during differential diagnosis. Some of the factors contributing to the emergence of diseases like CD are related to global warming, which brings about climate change, water eutrophication, the colonization of ponds by snails susceptible to the parasite, and sunlight exposure in the summer, associated with migratory bird routes. Therefore, with the increase in tourism, especially at fluvial beaches, it is relevant to analyze the current epidemiological scenario of CD in European countries and the potential regions at risk.

4 November 2021 in Infectious Disease Reports
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Journal Article
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AAAna Margarida Alho
Ana Margarida Alho
Pedro Manuel FerreiraPedro Manuel Ferreira
Pedro Manuel Ferreira
ICIsabel Clemente
Isabel Clemente
MGMaria Amélia A. Grácio
Maria Amélia A. Grácio
Silvana Maria Duarte BeloSilvana Maria Duarte Belo
Silvana Maria Duarte Belo
Toxocariasis is one of the most widespread and important zoonotic parasitic diseases, although neglected. Data regarding human Toxocara infection in Portugal are almost absent. This article gives an overview of the situation of toxocariasis in Portugal over the last decade based on casuistic data. A total of 846 serum samples from individuals suspected of toxocariasis, collected from 2010 to 2020, were analyzed at the Institute of Hygiene and Tropical Medicine. Sera were tested for IgG antibodies to Toxocara canis excreted–secreted larval antigens by enzyme-linked immunosorbent assay and counterimmunoelectrophoresis. Positivity was detected in 18.8% (159/846) [CI 95%: 16.3–21.6], with positives detected throughout continental Portugal. Overall, 59.7% of the positives were diagnosed in younger than 20 years (35.2% aged 0–9 years and 24.5% aged 10–19 years). Eosinophilia was the most frequent feature reported (27.7%). Pediatrics (41.5%) and Infectiology (25.8%) were the specialties with the highest number of positives. An average of 77 samples/year were received, recording a maximum positivity in 2012 (41.5%, n = 27/65) and a minimum in 2020 (6.4%, n = 3/47). These numbers may reflect the effectiveness of current preventive measures, highlighting the need to maintain public awareness to control this helminthozoonosis and promote a higher public health standard.

27 April 2023 in Plants
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Journal Article
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MVMaria dos Anjos Samuel Quilombo Valente
Maria dos Anjos Samuel Quilombo Valente
Pedro Manuel FerreiraPedro Manuel Ferreira
Pedro Manuel Ferreira
KLKatelene Soraia Pereira Lima
Katelene Soraia Pereira Lima
ISIsabel Bettencourt Moreira da Silva
Isabel Bettencourt Moreira da Silva
PNPaula Nobre
Paula Nobre
OSOlga Maria Duarte Silva
Olga Maria Duarte Silva
Vernonia britteniana Hiern. (Asteraceae) is a medicinal plant used in traditional Angolan medicine against schistosomiasis. Our study aimed to investigate the phytochemical composition and the cercaricidal and antioxidant activities in vitro of a traditional herbal preparation (Water-Vbr) and a 70% hydroethanolic extract (EtOH70%-Vbr) prepared with this medicinal plant. The activity of the extracts against Schistosoma mansoni cercariae was assessed at different extract concentrations (500, 438, and 125 µg/mL) and at different time intervals, and the phytochemical profiles were obtained by LC-UV-ESI/MS-MS. In addition, the major chemical classes of the identified metabolites were quantified by colorimetry, and the antioxidant potential was assessed using the DPPH and FRAP methods. After 30 min, 100% cercarial mortality was observed at a concentration of 500 μg/mL after exposure, and after 120 min, an LC50 of 438 μg/mL was observed for both extracts. Phenolic acid derivatives (chlorogenic acid, caffeic acid; 3,4-di-O-caffeoylquinic acid; 3,5-di-O-caffeoylquinic acid; and 4,5-di-O-caffeoylquinic acid) and triterpenoids (stigmastane-type steroidal saponins; vernoamyoside D and vernonioside D1; vernoamyoside B; and vernoniamyoside A and C) were identified as the main secondary metabolites. The Water-Vbr extract showed the highest antioxidant activity—DPPH: IC50 = 1.769 ± 0.049 µg/mL; FRAP: mean = 320.80 ± 5.1325 µgAAE/g.

23 March 2025 in Pathogens
Verified
Journal Article
Open access
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Maria Teresa BispoMaria Teresa Bispo
Maria Teresa Bispo
Isabel MauricioIsabel Mauricio
Isabel Mauricio
Pedro Manuel FerreiraPedro Manuel Ferreira
Pedro Manuel Ferreira
Silvana Maria Duarte BeloSilvana Maria Duarte Belo
Silvana Maria Duarte Belo
MCMaria Manuela Calado
Maria Manuela Calado
Physella acuta is an invasive freshwater snail with a global distribution and a recognized role as an intermediate host for various trematodes, including Echinostoma spp. and Trichobilharzia physellae. In Portugal, P. acuta is commonly found in freshwater bodies such as Lake Alqueva, the largest artificial reservoir in Europe. The lake’s creation has altered local ecosystems, influencing freshwater snail populations and migratory bird activity, which may contribute to the dispersal of trematode parasites. While P. acuta is present in the region, its role in trematode transmission remains unclear. This study investigated P. acuta as a potential intermediate host for trematodes in Lake Alqueva. Freshwater snails were collected from 18 sites, with cercarial shedding induced under artificial light. Infected snails were found in 2 of the 18 snail populations surveyed. A sequence analysis of the amplified ITS2 rDNA region confirmed the presence of Posthodiplostomum sp., implicating, for the first time, P. acuta as an intermediate host for this parasite in Portugal. This study highlights the need for further research on P. acuta’s role in trematode transmission and potential impact on local ecosystems to assess parasitic risks to veterinary and public health.