Browsing by Author "Ferreira, C."
Now showing 1 - 4 of 4
Results Per Page
Sort Options
- Correlates of children's physical activity during the COVID-19 confinement in PortugalPublication . Pombo, André; Luz, Carlos; Rodrigues, Luis P.; Ferreira, C.; Cordovil, R.Objectives: The aim of the study was to understand the role of household variables on the percentage of physical activity (%PA) during the coronavirus disease 2019 (COVID-19) confinement in Portugal. Study design: A cross-sectional study design using an anonymous online survey was launched to assess how Portuguese families with children aged younger than 13 years adjusted their daily routines to the confinement. Methods: Separate analyses of variance were performed to investigate how factors such as the number of children, age, sex, the housing characteristics, and the adults' job situation can affect the percentage of time for PA (%PA). Results: Findings, based on data from 2159 children, indicate that (1) boys and girls did not differ in the %PA on any of the age-groups; (2) children with an outdoor space and who had other children in the household were significantly more active (P < .001); (3) children from families with all adults working from home showed lower levels of %PA; and (4) being younger, having a big outdoor space, having other children in the household, and having at least one adult free from working from home were significant positive predictors of children's %PA, explaining 21% of the overall variance. Conclusion: Time allocated for PA during this period is reduced compared with what is usually reported on normal days. It is necessary to find strategies to increase children's PA, especially in families in which both parents are working and have no outdoor space.
- Modified auramine-rhodamine stain contribution to identify mycobacterium tuberculosisPublication . Ruivo, L.; Fialho, M. Pinto; Santos, H. S.; Tavares, J. A.; Ferreira, C.Background & objectives: Mycobacterium tuberculosis (MT) infection often causes multiple organ granulomatous disease. Suspicious lesions are often biopsied to exclude malignancy. Ziehl-Neelsen (ZN) staining is the histological standard diagnostic tool for MT, although auramine-rhodamine (AR) appears to have better detection ratios. Methods: We evaluated all biopsies with suspected clinical tuberculosis (combined or not with microbiological testing), from January 2022 to September 2023 in a tertiary hospital center, with histological confirmation of granulomatous inflammation and tested with ZN staining. The biopsies were reevaluated using AR staining with a modified protocol in which phenol was replaced by a trident for cell membrane permeabilization. Results: The study comprised 53 cases, 27 females and 26 males. The most frequent biopsy sites were lymph nodes (38% - 20/53) and lung (36% - 19/53). Necrotizing granulomatous inflammation was found in 75% of cases (41/53), 32% of which (13/41) tested positive for ZN stain and were further confirmed with modified AR. From the remaining ZN-negative cases (68% - 28/41), 39% (11/28) tested positive in the microbiological study; from those, 73% (8/11) were positive using modified AR. Conclusion: Although ZN is the histological gold standard method to assess the presence of MT, its evaluation is hampered by the fact that the number of mycobacteria is often below the technique’s detection threshold. AR has greater sensitivity and easier fluorescence visualization, even at lower magnification and with fewer bacilli. Additionally, the proposed modification in the technical protocol for AR, makes it less harmful for the performer and does not compromise the quality of the technique.
- Pozzolanic activity of oil-refining catalyst: evaluation by electron and atomic microscopyPublication . Jeremias, J.; Nogueira, I.; Nolasco, P.; Carvalho, P. A.; Ferreira, C.; Costa, CarlaThe reuse of waste fluid catalytic cracking (FCC) catalyst as partial surrogate for cement can reduce the environmental impact of both the oil-refinery and cement production industries [1,2]. FCC catalysts can be considered as pozzolanic materials since in the presence of water they tend to chemically react with calcium hydroxide to produce compounds possessing cementitious properties [3,4]. In addition, partial replacement of cement with FCC catalysts can enhance the performance of pastes and mortars, namely by improving their compressive strength [5,6]. In the present work the reaction of waste FCC catalyst with Ca(OH)2 has been investigated after a curing time of 28 days by scanning electron microscopy (SEM) with electron backscattered signal (BSE) combined with X-ray energy dispersive spectroscopy (EDS) carried out with a JEOL JSM 7001F instrument operated at 15 kV coupled to an INCA pentaFetx3 Oxford spectrometer. The polished cross-sections of FCC particles embedded in resin have also been evaluated by atomic force microscopy (AFM) in contact mode (CM) using a NanoSurf EasyScan 2 instrument. The SEM/EDS results revealed that an inward migration of Ca occurred during the reaction. A weaker outward migration of Si and Al was also apparent (Fig. 1). The migration of Ca was not homogeneous and tended to follow high-diffusivity paths within the porous waste FCC catalyst particles. The present study suggests that the porosity of waste FCC catalysts is key for the migration/reaction of Ca from the surrounding matrix, playing an important role in the pozzolanic activity of the system. The topography images and surface roughness parameters obtained by atomic force microscopy can be used to infer the local porosity in waste FCC catalyst particles (Fig. 2).
- Sebaceous carcinoma in a mature cystic teratoma of the ovaryPublication . Fialho, M. Pinto; Gradil, A.; Ferreira, C.; Lérias, S.Background & objectives: Sebaceous carcinoma originating within an ovarian mature cystic teratoma (MCT) is an extremely rare entity. To the best of our knowledge, less than 14 cases have been reported in the literature. Methods: We report a case of a sebaceous carcinoma arising within a mature teratoma. Results: An 83-year-old female presented with urinary retention symptoms. A pelvic MRI scan revealed a left ovary lesion consistent with MCT. The patient underwent a bilateral adnexectomy. Macroscopically an 18cm ovary cystic mass showed a partially solid appearance intermixed with soft yellow sebaceous material. Histological examination revealed an MCT with a lobular component containing sebocytes surrounded by basaloid cells with focal squamoid features, nuclear pleomorphism, increased mitosis, and associated necrosis. Basaloid cells were immunoreactive to p63 and CK5/6. Sebaceous cells were EMA+ and PRAME+. Mismatch repair protein nuclear expression was intact. A diagnosis of a sebaceous carcinoma arising within an MCT was made. The patient is free of disease at 17 months. Conclusion: Sebaceous carcinoma within an ovarian MCT is a rare entity. Although ocular sebaceous carcinomas are aggressive, the prognosis of extraocular sebaceous carcinoma is thought to be better since local recurrence or metastasis has not yet been described. Given the paucity of data, the management of these patients remains unclear, however identifying tumor microsatellite instability or germline DNA mutations facilitates further cancer screening and treatment (PD1/PD-L1 inhibitors).