Faculdade de Medicina e Ciências Biomédicas
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Percorrer Faculdade de Medicina e Ciências Biomédicas por Objetivos de Desenvolvimento Sustentável (ODS) "02:Erradicar a Fome"
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- High vs low protein intake in chronic critical illness: a systematic review and meta-analysisPublication . Castro, Sílvia; Tome, Ana Maria; Granja, C.; Macedo, A.; Binnie, AlexandraBackground & aims: Patients with persistent organ dysfunction after the first week of intensive care unit (ICU) admission are considered to have chronic critical illness (CCI). Acquired muscle weakness is a common feature of CCI that is accompanied by loss of muscle mass and electromyographic features of myopathy. Optimizing protein intake may help prevent acquired muscle weakness and/or promote muscle recovery, however, the optimal level of protein intake in CCI is uncertain and there is a lack of consensus in published nutritional guidelines. This systematic review focuses on the impact of high versus low protein intake as part of a nutritional strategy for patients with CCI. Methods: The terms “protein intake” and “critically ill” were systematically searched in PUBMED, CENTRAL (Cochrane Central Register of Controlled Trials), and WEB OF SCIENCE on 06/01/2023. We included studies that (1) enrolled critically ill adults (aged 18 years or over) who were in the ICU for more than 7 days and that compared (2) protein intake above and below 1.3 gr/kg administered by any route (enteral and/or parenteral), (3) had an intervention period that occurred primarily after the first 7 days of critical illness and (4) reported clinical outcomes including length of ICU and hospital stay, duration of invasive mechanical ventilation (IMV), mortality, ICU acquired infections, muscle mass and physical function. Studies pertaining to elective surgery, those with intervention periods shorter than 7 days or occurring primarily within the first 7 days of critical illness, those measuring only laboratory parameters as outcomes, and safety and feasibility studies were excluded. Results: Four studies were included (N ¼ 1730) in the meta-analysis and systematic review. Higher (>1.3 g/kg/d) versus lower protein intake was associated with a decrease in early mortality (defined as ICU or 28-day mortality) hazard ratio (HR) 0.42 (95 % confidence interval (CI): 0.26e0.70, P < 0.001), but had no impact on late mortality (defined as the latest mortality timepoint in each study): HR 0.93 (95 % CI 0.76e1.15, P ¼ 0.51). There was no significant difference between intervention and control groups with respect to duration of IMV, duration of ICU or hospital stay, muscle mass, or the incidence of ICUacquired infections. One study reported improvements in physical function at 3 and 6 months in the intervention group. Conclusion: After the first week of critical illness, increasing protein intake to >1.3 g/kg/d may improve early mortality but not late mortality or other clinical outcomes. The small number of relevant studies and the heterogeneity of outcomes assessed, weaken these conclusions. Further studies are warranted to discern whether higher protein intake is beneficial in chronic critical illness. PROSPERO registration number: CRD42023403554; PROSPERO registration name: “The effect of higher than 1,3 g/kg of protein versus lower intake in chronic critically ill patients”
- The influence of inflammatory processes in fish skeletal development: the crosstalk between skeletal and immune systemsPublication . Martins, Gil Sales Marques; Gavaia, Paulo Jorge Travessa; Abellán, Francisco António GuardiolaOsteoimmunology is an emerging field focused on the comprehension of the crosstalk between the immune and skeletal systems, with a particular focus on how inflammation affects bone health and disease. Previous research suggests that the same signalling mechanism that occurs in mammals may trigger the differentiation of macrophages into osteoclasts in teleosts, leading to the onset of pathological bone resorption by an identical molecular process. However, little is known about the contribution of the inflammatory processes and or bacterial constituents in fish bone tissues. In this thesis, we tackle this issue by evaluating the impact of continuous exposure to bacterial lipopolysaccharides (LPS) in zebrafish dermal skeleton (scales) and evaluating the potential of the microalga Tisochrysis lutea ethanolic extract and its glycolipid (GL) fractions to reverse the LPS effects. The continuous exposure to LPS led to the reduction of de novo formed scales and led to scale demineralization, with increased osteoclast activity, and inflammatory and osteoclastic marker genes (i.e., tnfa, ctsk, and acp5). In ex vivo cultured scales, LPS led to an increase in the number of osteoclast areas, while reducing the number of macrophages. An overlap between cell types and TRAP+ signals indicates the possible differentiation of macrophages into osteoclasts. T. lutea extract and two isolated glycolipid fractions (Tl-glF1 and Tl-glF2) evidenced an anti-osteoclastic potential against the differentiation of RAW 264.7-derived osteoclasts (RAW-Ocs), with a reduced number of mono- and multinucleated osteoclasts. The data collected in this thesis supports the use of zebrafish scales exposed to LPS at 10 μg mL-1 as an in vivo and ex vivo screening method for searching novel anti-resorptive compounds for inflammatory diseases, to study the mechanisms involved in increased bone resorption, and the role of LPS in the differentiation of macrophages into osteoclasts. T. lutea GLs contain anti-resorptive properties and should be further investigated for their application in osteoimmune diseases.
- Metabolism and the impact of protein intake in chronic critically ill adult patients: protocol for a unicentric prospective cohort study (MetaChronic Study)Publication . Castro, Sílvia; Granja, Cristina; Dionne, Joanna C.; Pires, Teresa; Oliveira, Carolina; Binnie, AlexandraBackground: Survival of acutely critically ill patients has improved, resulting in a growing population of chronic critically ill (CCI) patients with prolonged organ dysfunction, mechanical ventilation, and high morbidity. While nutritional guidelines during the acute phase of critical illness are well defined, our understanding of metabolism and nutritional needs in CCI patients is limited. Persistent inflammation may influence the metabolic response and nutritional uptake, highlighting the need for prospective studies in this area. Methods: The MetaChronic Study is a single-center, prospective cohort study of metabolism in patients with CCI. Adult ICU patients with invasive mechanical ventilation ≥48 h and ICU stay >7 days are eligible. Patients are followed for up to 42 days after ICU admission, with final outcomes assessed at 90 days. Resting energy expenditure is measured weekly by serial indirect calorimetry. Weekly protein and calorie intake are recorded and inflammation is assessed using serum C-reactive protein and procalcitonin measurements. Patients are categorized according to high or low protein intake (>1.3 g/kg/ day vs. ≤1.3 g/kg/day after the first week). The primary objective is to characterize longitudinal metabolic trajectories. Secondary objectives include subgroup analyses (septic, trauma, neurocritical patients), assessment of the interaction between inflammation and metabolic rate, and exploratory analyses of the association between protein intake and clinical outcomes. Ethics and dissemination: The study has been approved by the institutional ethics committee. Findings will be disseminated through peer-reviewed journals and scientific conferences.