MAPK signaling pathways mediate acetic acid-induced cell death in saccharomyces cerevisiae

This work was funded by FEDER through the program “Programa Operacional Factores de Competitividade-COMPETE” and by FCT through the projects Pest-C/BIA/UI4050/2011 and FCOMP-01-0124-FEDER-007047. F.A. was supported by an FCT fellowship (FCOMP-01-0124-FEDER-007047)

Comparison of Nasopharyngeal Samples for SARS‐CoV ‐2 Detection in a Paediatric Cohort

Aim: The diagnosis of coronavirus disease 2019 (COVID-19) depends on accurate and rapid testing. Choosing an appropriate sample may impact diagnosis. Naso-oropharyngeal swabs (NOS) are most frequently used, despite several limitations. Since studies suggest nasopharyngeal aspirate (NPA) as a superior alternative in children, we hypothesised collecting both nasopharyngeal swab and aspirate would improve our diagnostic accuracy. Methods: Observational, longitudinal, prospective study from 7 March to 7 May in a tertiary paediatric hospital in Lisbon. The objective was to compare the rate of detection of SARS-CoV-2 between NOS and NPA samples collected simultaneously. Results: A total of 438 samples collected from 85 patients with confirmed COVID-19. There were 47.7% overall positive specimens - 32% (70/219) positive NOS and 63.5% (139/219) positive NPA. The tests were 67.6% concordant (k = 0.45). 50.3% had positive NPA with negative NOS, while 1.3% had positive NOS with negative NPA. NPA proved to be more sensitive (98.6% with 95% confidence interval 91.2-99.9% vs. 49.6% with 95% confidence interval 41.1-58.2%, P < 0.001). Additionally, the difference between NPA and NOS positive samples was statistically significant across all population groups (age, health condition, clinical presentation, contact with COVID-19 patients or need for hospitalisation), meaning NPA is more sensitive overall. Conclusions: Nasopharyngeal aspirates had greater sensitivity than naso-oropharyngeal swabs in detecting SARS-CoV-2. Our results suggest paediatric patients would benefit from collecting nasopharyngeal aspirates in hospital settings, whenever feasible, to improve diagnosis of COVID-19.info:eu-repo/semantics/publishedVersio

Kikuchi's disease associated with Epstein-Barr virus infection

info:eu-repo/semantics/publishedVersio

The involvement of sphingolipids in apoptosis induced by acetic acid in yeast

This work was funded by FEDER through the program “Programa Operacional Factores de Competitividade-COMPETE” and by FCT (Fundação para a Ciência e Tecnologia) through the projects Pest-C/BIA/UI4050/2011 and FCOMP-01-0124-FEDER-007047. A.R. was supported by a FCT fellowship (FCOMP-01-0124-FEDER-007047)

How can a milk protein selectively kill cancer cells? Mechanisms underlying lactoferrin-induced apoptosis

Lactoferrin (Lf) is an iron-binding protein abundant in milk that has been shown to exhibit anticancer activity. Since Lf is non-toxic to cancer cells (1) and is well tolerated in humans (2), this protein has a huge potential to be used in cancer therapy. However, the targets and mechanisms underlying its selective anticancer activity are poorly elucidated, which limits its clinical exploitation. The recruitment of the proton pump V-ATPase to the plasma membrane, where it mediates the acidification of the tumor microenvironment, is a recognized feature involved in the acquisition of a metastatic phenotype in different cancers, including breast cancer. Therefore, inhibitors of this pump have emerged as promising anticancer drugs. Here we show that bovine lactoferrin (bLf) preferentially inhibits cell proliferation and induces apoptosis in two highly metastatic breast cancer cell lines, which display a prominent localization of V-ATPase at the plasma membrane, but not in a lowly metastatic or a non-tumorigenic cell lines (3). We then characterized the mechanism underlying bLf-induced apoptosis and demonstrated that bLf selective cytotoxicity is caused by the inhibition of extracellular acidification rate and the ensuing intracellular acidification in the highly metastatic breast cancer cells. Accordingly, bLf, like the well-known proton pump inhibitors concanamycin A and bafilomycin A1, inhibits V-ATPase proton pumping and hydrolytic activities in sub-cellular fractions enriched in this proton pump. We recently also demonstrated that bLf preferentially induces apoptosis in other types of highly metastatic cancer cells other than breast (4). Altogether, our data demonstrated for the first time that bLf acts as a V-ATPase inhibitor and established a common mechanism of action of bLf against highly metastatic cancer cell exhibiting this proton pump at the plasma membrane. This study opens promising perspectives for the safer and more rational application of bLf in the therapy of these life-threatening cancers. 1. Gibbons JA et al. (2015) BMC Cancer doi: 10.1186/s12885-015-1441-4. 2. Hayes TG et al. (2010) Invest New Drugs doi: 10.1007/s10637-009-9233-9. 3. Pereira CS et al. (2016) Oncotarget doi: 10.18632/oncotarget.11394. 4. Guedes JP et al. (2018) Frontiers in Oncology doi.org/10.3389/fonc.2018.00200info:eu-repo/semantics/publishedVersio

Exploring a novel effect of lactoferrin on the plasma membrane towards the elucidation of the mechanisms of action: from yeast to human cells

Microbiotec'17 - Congress of Microbiology and Biotechnology 2017info:eu-repo/semantics/publishedVersio

Yeast as a tool to explore cathepsin D function

Cathepsin D has garnered increased attention in recent years, mainly since it has been associated with several human pathologies. In particular, cathepsin D is often overexpressed and hypersecreted in cancer cells, implying it may constitute a therapeutic target. However, cathepsin D can have both anti- and pro-survival functions depending on its proteolytic activity, cellular context and stress stimulus. Therefore, a more detailed understanding of cathepsin D regulation and how to modulate its apoptotic functions is clearly needed. In this review, we provide an overview of the role of cathepsin D in physiological and pathological scenarios. We then focus on the opposing functions of cathepsin D in apoptosis, particularly relevant in cancer research. Emphasis is given to the role of the yeast protease Pep4p, the vacuolar counterpart of cathepsin D, in life and death. Finally, we discuss how insights from yeast cathepsin D and its role in regulated cell death can unveil novel functions of mammalian cathepsin D in apoptosis and cancer.FEDER through POFC – COMPETE and by Fundação para a Ciência e Tecnologia through projects PEst-OE/BIA/UI4050/2014 and FCTANR/BEX-BCM/0175/2012, as well as fellowships to H. Pereira (SFRH/BD/73139/2010), C.S.F. Oliveira (SFRH/BD/77449/2011), L. Castro (SFRH/BD/93589/2013) and S. Chaves (SFRH/ BPD/89980/2012).info:eu-repo/semantics/publishedVersio

Insights on the molecular mechanisms underlying the anticancer activity of lactoferrin in metastatic cancer cell lines

Lactoferrin (Lf) is an iron-binding protein derived from milk that is present in many tissues and biological fluids. It has been shown that this natural compound exihibits anticancer and anti-metastatic activities as well as cytotoxicity against several cancer cell lines. We have recently found that bovine lactoferrin (bLf) selectively triggers cell death in highly metastatic breast cancer cells through inhibition of the plasmalemmal proton pump V-H+-ATPase.1 In the present study we aim to determine whether this mechanism of action underlies the anticancer/anti-metastatic activity of bLf in metastatic cancer cells other than breast cancer cells. To this end, we assessed bLf-induced inhibition of cell proliferation and intracellular acidification of a prostate and an osteosarcoma metastatic cell line and compared it with the effects on the previously used metastatic breast cancer cell line. The possibility of a common molecular target/mechanism of action of bLf underpinning its anticancer/anti-metastatic activity will be discussed

Artroscopia do Tornozelo Anterior vs Posterior. Comparação de Resultados e Complicações

Introdução: Recentemente têm surgido debates na literatura internacional acerca da segurança e necessidade da abordagem artroscópica posterior para tratamento da patologia intra e extra articular do tornozelo. A artroscopia por via posterior realiza-se utilizando portais postero-interno e postero-externo, e com o doente em decúbito ventral. Permite acesso à região posterior do tornozelo, articulação subtalar, osso trígono, tendões peroneias e tendão do Longo flexor do Hallux, e ainda à porção posterior do ligamento deltoideu. Permite ainda uma melhor visualização, menor morbilidade e recuperação mais rápida que na abordagem a céu aberto. Neste estudo comparamos os resultados clínicos e funcionais e dos doentes submetidos a apenas a artroscopia anterior e dos doentes submetidos a artroscopia anterior e posterior do tornozelo, bem como as complicações independentemente da patologia inicial. Material e Métodos: Estudo retrospectivo, tendo sido analisados os processos clínicos de todos os doentes submetidos a tratamento artroscópico do tornozelo em duas instituições, pelo mesmo cirurgião. De um universo de 299 procedimentos artroscópicos do tornozelo, excluímos todos os casos em que foi utilizada concomitantemente uma via aberta para tratamento de outras lesões. Obtivémos resultados clínicos e funcionais de 185 doentes, 97 homens, 88 mulheres, tendo sido aplicado o score Aofas para o retropé e tornozelo. Foi realizada artroscopia posterior em 87 doentes e anterior em 98 doentes. A média de idades foi de 36 anos (17‐59). O follow-up mínimo foi de 6 meses (6‐60). Cento e trinta e dois doentes apresentavam patologia de origem traumática, e destes, 105 estavam relacionados com acidentes de trabalho. Resultados: Artroscopia anterior: a média do score Aofas foi de 87(43‐ 100). Oitenta e sete doentes retomaram a sua atividade profissional ou desportiva previa, e 16 doentes ainda não retomaram atividade na altura da avaliação. O tempo médio de retorno à atividade previa foi de 4 meses (2‐10). Registamos complicações em 13 doentes. Estas incluem infecção superficial das postas de entrada (3 casos), síndrome de dor regional complexa (3 casos), artrofibrose (2 casos), recidiva da lesão inicial (5 casos). Foram reoperados 6 doentes (2 casos de artrofibrose e 4 por recidiva da patologia inicial)Artroscopia anterior e posterior: a média do score Aofas foi de 83 (38‐100). Setenta e cinco doentes já retomaram a sua atividade prévia, sendo que 10 ainda se encontram em tratamento. O tempo médio de retorno à atividade foi de 4,3 meses (2‐ 12). Registámos complicações em 10 doentes (11,4%). Estas incluem 4 casos de lesão do nervo peroneal superficial, dos quais 3 recuperaram totalmente, 3 casos de artrofibrose, 2 casos de síndrome de dor regional complexa e 1 caso de infecção superficial das portas de entrada. Foram reoperados 4 doentes, dos quais 2 por artrofibrose, 2 casos por recidiva da patologia inicial. Discussão: Constatamos que a média do score Aofas e a taxa de complicações é sobreponível entre as duas diferentes abordagens. Os nossos resultados, em termos de complicações, são ligeiramente inferiores aos publicados na literatura internacional, quer para a artroscopia anterior, quer para a anterior e posterior, o 7 que poderá estar relacionado com o elevado número de doentes com lesões relacionadas com acidentes de trabalho. Conclusão: A abordagem posterior não tem mais complicações que a abordagem anterior isolada. Os resultados em doentes vítimas de acidente de trabalho são inferiores em ambas as abordagens. Os resultados e complicações de ambas as abordagens são sobreponíveis aos da literatura internacional

Luxação Palmar Isolada da Quinta Articulação Carpo-Metacárpica

A luxação palmar isolada da quinta articulação carpo-metacárpica é rara. Esta lesão pode passar despercebida, sendo importante a suspeita clínica, levando a uma avaliação radiológica no perfil e incidências obliquas. O tratamento é controverso, estando descritas a redução fechada com fixação percutânea com fios de Kirshner percutâneos e a redução aberta com fixação interna. Apresentamos um caso clínico de luxação palmar do tipo cubital isolada e o seu tratamento. O resultado funcional aos 6 meses, de acordo com o score DASH, foi de 0.8. Apresentava-se sem queixas, desempenhado as suas atividades diárias sem restrições.info:eu-repo/semantics/publishedVersio