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- Nanoplastics activate a TLR4/p38-mediated pro-inflammatory response in human intestinal and mouse microglia cellsPublication . Antunes, Joana; Sobral, Paula; Martins, Marta; Branco, VascoThe crescent presence of nanoplastics in the environment raises concerns regarding their potential impact on health. This study exposed human colon adenocarcinoma cells (HT29) and microglia cells (N9) to nanoplastics (25 nm, 50 nm, and 100 nm Polystyrene) to investigate their inflammatory responses, which are vital for body's defence. Although cytotoxicity remained generally low, HT29 cells exhibited a notable upregulation of p50 and p38 expression, concomitant with elevated TLR4 expression, in contrast with N9 cells that showed a less pronounced upregulation of these proteins. Additionally, nanoplastic exposure increased IL-1ß levels, partially attenuated by pre-exposure to TLR4 or p38 inhibitors. Intriguingly, N9 cells exposed to nanoplastics exhibited substantial increases in iNOS mRNA. This effect was entirely prevented by pre-exposure to TLR4 or p38 inhibitors, while TNF-α mRNA levels remained relatively stable. These findings underscore the potential of nanoplastics to activate inflammatory pathways, with response kinetics varying depending on the cell type.
- Nanocarriers in Tuberculosis treatment : challenges and delivery strategiesPublication . Kumar, Mahesh; Virmani, Tarun; Kumar, Girish; Deshmukh, Rohitas; Sharma, Ashwani; Duarte, Sofia; Brandão, Pedro; Fonte, PedroThe World Health Organization identifies tuberculosis (TB), caused by Mycobacterium tuberculosis, as a leading infectious killer. Although conventional treatments for TB exist, they come with challenges such as a heavy pill regimen, prolonged treatment duration, and a strict schedule, leading to multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains. The rise of MDR strains endangers future TB control. Despite these concerns, the hunt for an efficient treatment continues. One breakthrough has been the use of nanotechnology in medicines, presenting a novel approach for TB treatment. Nanocarriers, such as lipid nanoparticles, nanosuspensions, liposomes, and polymeric micelles, facilitate targeted delivery of anti-TB drugs. The benefits of nanocarriers include reduced drug doses, fewer side effects, improved drug solubility, better bioavailability, and improved patient compliance, speeding up recovery. Additionally, nanocarriers can be made even more targeted by linking them with ligands such as mannose or hyaluronic acid. This review explores these innovative TB treatments, including studies on nanocarriers containing anti-TB drugs and related patents.
- Muscle activity variability patterns and stride to stride fluctuations of older adults are positively correlated during walkingPublication . Jordão, Sofia; Stergiou, Nick; Brandão, Rita; Pezarat-Correia, Pedro; Oliveira, Raúl; Cortes, Nelson; Vaz, João R.It has been found that fractal-like patterns are present in the temporal structure of the variability of healthy biological rhythms, while pathology and disease lead to their deterioration. Interestingly, it has recently been suggested that these patterns in biological rhythms are related with each other, reflecting overall health or lack of it, due to their interaction. However, the underlying neurophysiological mechanisms responsible for such dependency remain unknown. In addition, this relationship between different elements needs to be first verified before we even pursue understanding their interaction. This study aimed to investigate the relationship between two elements of the neuromuscular system, gait and muscle activity variability patterns in older adults. Twenty-one older adults walked at their preferred walking speed on a treadmill. Inter-stride intervals were obtained through an accelerometer placed on the lateral malleoli to assess the temporal structure of variability of stride-to-stride fluctuations. Inter muscle peak intervals were obtained through the electromyographic signal of the gastrocnemius to assess the temporal structure of the variability of the simultaneous muscle activity. The temporal structure of variability from both signals was evaluated through the detrended fluctuation analysis, while their magnitude of variability was evaluated using the coefficient of variation. The Pearson’s Correlation coefficient was used to identify the relationship between the two dependent variables. A significant strong positive correlation was found between the temporal structure of gait and muscle activity patterns. This result suggests that there is an interdependency between biological rhythms that compose the human neuromuscular system.
- Modifying dental composites to formulate novel methacrylate-based bone cements with improved polymerisation kinetics, and mechanical propertiesPublication . Khan, Muhammad Adnan; Delgado, António H. S.; Young, Anne M.Objectives: The aim was to develop bone composites with similar working times, faster polymerisation and higher final conversion in comparison to Cortoss™. Additionally, low shrinkage/heat generation and improved short and longer-term mechanical properties are desirable. Methods: Four urethane dimethacrylate based composites were prepared using tri-ethylene-glycol dimethacrylate (TEGDMA) or polypropylene dimethacrylate (PPGDMA) diluent and 0 or 20 wt% fibres in the glass filler particles. FTIR was used to determine reaction kinetics, final degrees of conversions, and polymerisation shrinkage/heat generation at 37 °C. Biaxial flexural strength, Young’s modulus and compressive strength were evaluated after 1 or 30 days in water. Results: Experimental materials all had similar inhibition times to Cortoss™ (140 s) but subsequent maximum polymerisation rate was more than doubled. Average experimental composite final conversion (76%) was higher than that of Cortoss™ (58%) but with less heat generation and shrinkage. Replacement of TEGDMA by PPGDMA gave higher polymerisation rates and conversions while reducing shrinkage. Early and aged flexural strengths of Cortoss™ were 93 and 45 MPa respectively. Corresponding compressive strengths were 164 and 99 MPa. Early and lagged experimental composite flexural strengths were 164–186 and 240–274 MPa whilst compressive strengths were 240–274 MPa and 226–261 MPa. Young’s modulus for Cortoss™ was 3.3 and 2.2 GPa at 1 day and 1 month. Experimental material values were 3.4–4.8 and 3.0–4.1 GPa, respectively. PPGDMA and fibres marginally reduced strength but caused greater reduction in modulus. Fibres also made the composites quasi-ductile instead of brittle.
- Medicines and medication literacy : social practices and use of informationPublication . Lopes, Noémia; Pegado, Elsa; Egreja, Catarina; Rodrigues, Carla; Fernandes, Ana IsabelThis article discusses results from a sociological study on (i) the sources and use of information on medicines and/or supplements and (ii) the self-assessment of how informed participants were about the last medicine or supplement they purchased. It seeks to demonstrate the plurality of information sources (expert and lay) that individuals call upon—with which they build up their medication literacy—and their perception of the information they have. While these social components of literacy are scarcely visible in available studies, the need to produce knowledge on them is a requisite for a more laypeople-centred approach in public policies seeking to promote medication literacy. A questionnaire was applied in-person (n = 1107) in urban pharmacies in Lisbon and Porto (Portugal). Results show expert information (medical and pharmaceutical) as the dominant reference, followed by lay sources (family/friends/colleagues), while digital sources were less valued than interpersonal ones. This interpersonal dimension was a relevant factor in the building of trust in information. The self-assessment of the information on medication was higher in functional literacy and lower in comprehensive literacy. Studies on medication literacy are particularly relevant in the current context of the expansion and diversification of medicines’ use and of individuals’ growing autonomy in their consumption habits.
- Meat consumption and availability for its reduction by health and environmental concerns : a pilot studyPublication . Turnes, Andrea; Pereira, Paula; Cid, Helena; Valente, Ana(1) Background: Excessive meat consumption has raised multiple health and environmental concerns; however, there are no data on the population’s willingness to reduce its intake for these reasons. The current study aims to assess the frequency of meat intake and readiness to limit consumption due to concern about the impact on health and the environment in residents of the Lisbon metropolitan region. (2) Methods: This analytical cross-sectional observational study was carried out in 197 residents in the metropolitan region of Lisbon. The participants were divided into two groups by age (GI: 20–29 years; GII: 40–64 years). Meat consumption and willingness to reduce it were assessed through a questionnaire. (3) Results: Most participants (67%) reported not having knowledge about the ecological footprint of meat. Being a less frequent meat consumer (<1 time per day) is associated with a willingness 3.6 times higher (p < 0.001) to reduce meat consumption due to sensitivity to the impact on health and 4.0 times higher (p < 0.001) due to environmental reasons. (4) Conclusions: Lower meat consumption frequency was associated with reductions in this consumption for environmental and health reasons.
- Mass spectrometry imaging of in vitro Cryptosporidium parvum-infected cells and host tissuePublication . Anschütz, Nils H.; Gerbig, Stefanie; Ghezellou, Parviz; Silva, Liliana M. R.; Vélez, Juan Diego; Hermosilla, Carlos R.; Taubert, Anja; Spengler, BernhardCryptosporidium parvum is a zoonotic-relevant parasite belonging to the phylum Alveolata (subphylum Apicomplexa). One of the most zoonotic-relevant etiologies of cryptosporidiosis is the species C. parvum, infecting humans, cattle and wildlife. C. parvum-infected intestinal mucosa as well as host cells infected in vitro have not yet been the subject of extensive biochemical investigation. Efficient treatment options or vaccines against cryptosporidiosis are currently not available. Human cryptosporidiosis is currently known as a neglected poverty-related disease (PRD), being potentially fatal in young children or immunocompromised patients. In this study, we used a combination of atmospheric pressure scanning microprobe matrix-assisted laser desorption/ionization (AP-SMALDI) mass spectrometry imaging (MSI) and liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to determine and locate molecular biomarkers in in vitro C. parvum-infected host cells as well as parasitized neonatal calf intestines. Sections of C. parvum-infected and non-infected host cell pellets and infected intestines were examined to determine potential biomarkers. Human ileocecal adenocarcinoma cells (HCT-8) were used as a suitable in vitro host cell system. More than a thousand different molecular signals were found in both positive- and negative-ion mode, which were significantly increased in C. parvum-infected material. A database search in combination with HPLC-MS/MS experiments was employed for the structural verification of markers. Our results demonstrate some overlap between the identified markers and data obtained from earlier studies on other apicomplexan parasites. Statistically relevant biomarkers were imaged in cell layers of C. parvum-infected and non-infected host cells with 5 µm pixel size and in bovine intestinal tissue with 10 µm pixel size. This allowed us to substantiate their relevance once again. Taken together, the present approach delivers novel metabolic insights on neglected cryptosporidiosis affecting mainly children in developing countries.
- Malnutrition, cancer stage and gastrostomy timing as markers of poor outcomes in gastrostomy-fed head and neck cancer patientsPublication . Sousa-Catita, Diogo; Ferreira-Santos, Cláudia; Mascarenhas, Paulo; Oliveira, Cátia; Madeira, Raquel; Santos, Carla Adriana; André, Carla; Godinho, Catarina; Antunes, Luís; Fonseca, JorgeFor percutaneous endoscopic gastrostomy (PEG)-fed head and neck cancer (HNC) patients, risk markers of poor outcomes may identify those needing more intensive support. This retrospective study aimed to evaluate markers of poor outcomes using TNM-defined stages, initial anthropometry [body mass index (BMI), mid-upper arm circumference (MUAC), tricipital skinfold (TSF), mid-arm muscle circumference (MAMC)] and laboratory data (albumin, transferrin, cholesterol), with 138 patients, 42–94 years old, enrolled. The patients had cancer, most frequently in the larynx (n = 52), predominantly stage IV (n = 109). Stage IVc presented a four times greater death risk than stage I (OR 3.998). Most patients presented low parameters: low BMI (n = 76), MUAC (n = 114), TSF (n = 58), MAMC (n = 81), albumin (n = 47), transferrin (n = 93), and cholesterol (n = 53). In stages I, III, IVa, and IVb, MAMC and PEG-timing were major survival determinants. Each MAMC unit increase resulted in 16% death risk decrease. Additional 10 PEG-feeding days resulted in 1% mortality decrease. Comparing IVa/IVb vs. IVc, albumin and transferrin presented significant differences (p = 0.042; p = 0.008). All parameters decreased as severity of stages increased. HNC patients were malnourished before PEG, with advanced cancer stages, and poor outcomes. Initial MAMC, reflecting lean tissue, significantly increases survival time, highlighting the importance of preserving muscle mass. PEG duration correlated positively with increased survival, lowering death risk by 1% for every additional 10 PEG-feeding days, signaling the need for early gastrostomy.
- Lower calcium and iron intake in adolescent gymnasts : a case of concern for youth sports nutritionPublication . Vicente, Filipa; Holanda, Marcela; Ramalho, Renata; Mendes, João; Marques-Vidal, Pedro; Pereira, PaulaObjectives: Diet is important for the appropriate development and maturation of young amateur athletes. The aim of this study was to determine whether young gymnasts were consuming adequate amounts of nutrients, particularly calcium and iron. Methods: This cross-sectional survey was conducted in Portugal's Almada and Lisbon regions in 2020. To determine if participants’ diet was adequate, weight, height, and skinfold measurements were taken. Dietary consumption was examined using two 24-h recalls. We collected data from 66 participants (60% females, 12–18 y of age), of whom 82% had normal weight and 39% had ideal body fat. Results: The daily total energy intake (TEI) was1605 ± 601 kcal. Of the TEI, 19%, 31%, and 50% were comprised of protein, fat, and carbohydrates, respectively. The most often consumed protein sources were poultry and ultra-processed meat products (52% and 45%, respectively). The average daily consumption of calcium and iron was 626 ± 293 and 9 ± 3 mg, respectively. Only 2 of the 66 participants had calcium intake within recommended levels, and 1of 5 had iron intake within recommended levels, the percentage of which was lower in girls than boys (7.5% versus 38.5%, P < 0.05). Conclusions: Despite having a sufficient macronutrient distribution, Portuguese gymnasts consume a high amount of ultra-processed items and a low amount of calcium and iron. The low proportion of female gymnasts with adequate iron consumption is cause for worry in sports nutrition.
- Long-term intestinal failure and home parenteral support : a single center experiencePublication . Brito, Mariana; Padinha, Mafalda; Carlos, Sandra; Oliveira, Cátia; Santos, Ana Paula; Nunes, Gonçalo; Santos, Carla Adriana; Fonseca, JorgeIntroduction: Home parenteral nutrition (HPN) and/or home parenteral hydration (HPH) are the gold-standard treatment for patients with long-term intestinal failure (IF). The authors aimed to assess the impact of HPN/HPH on nutritional status and survival of long-term IF patients, as well as HPN/HPH-related complications. Methods: This was a retrospective study including IF patients under HPN/HPH followed in a single large tertiary Portuguese hospital. The data collected included demographics, underlying conditions, anatomical characteristics, type and duration of parenteral support, IF functional, pathophysiological, and clinical classifications, body mass index (BMI) at the beginning and end of follow-up, complications/hospitalizations, current patient status (deceased, alive with HPN/HPH, and alive without HPN/HPH), and cause of death. Survival after HPN/HPH beginning, until death or August 2021, was recorded in months. Results: Overall 13 patients were included (53.9% female, mean age 63.46 years), and 84.6% of patients presented type III IF and 15.4% type II. Short bowel syndrome caused 76.9% of IF. Nine patients received HPN and 4 HPH. Eight patients (61.5%) were underweight at the beginning of HPN/HPH. At the end of follow-up, 4 patients were alive without HPN/HPH, 4 maintained HPN/HPH, and 5 died. All patients improved their BMI (mean initial BMI 18.9 vs. 23.5 at the end, p < 0.001). Eight patients (61.5%) were hospitalized due to catheter-related complications, mainly infectious (mean hospitalization episodes 2.25, mean hospital stay of 24.5 days). No deaths were related to HPN/HPH. Conclusion: HPN/HPH significantly improved IF patients’ BMI. HPN/HPH-related hospitalizations were common, however causing no deaths, reinforcing that HPN/HPH is an adequate and safe therapy for long-term IF patients.