Gracia Castro-Luna

Post-acute Neurological Sequelae of SARS-CoV-2 infection (Neuro-PASC) contribute substantially to Long COVID-related disability, with cognitive impairment, chronic fatigue, dysautonomia, and neuropsychiatric symptoms among its most debilitating manifestations. Although its pathogenesis remains incompletely understood, evidence implicates persistent immune activation, intestinal barrier dysfunction, microbiota dysbiosis, microbiome-derived metabolic alterations, mitochondrial dysfunction, and neuroimmune interactions in sustaining neuroinflammation and neurological impairment. This narrative review examines precision nutrition as a potential pathway-oriented strategy for Neuro-PASC. We synthesise evidence linking the gut microbiota, intestinal permeability, immunometabolic pathways, mitochondrial function, and neurological outcomes, while evaluating nutritional interventions targeting these mechanisms. We focus on candidate biomarkers, including serum zonulin, fatty acid-binding protein 2 (FABP2), faecal short-chain fatty acids (SCFAs), and the kynurenine-to-tryptophan ratio, which may support patient stratification and personalised nutritional strategies. We also propose a stepwise framework involving dietary stabilisation, functional foods, targeted supplementation, and microbiome-based interventions, alongside practical considerations for post-exertional symptom exacerbation, dysautonomia, and mast cell-related symptoms. Finally, we identify priorities for future research, including multi-omics integration, artificial intelligence, digital health, and biomarker-stratified randomised controlled trials. Because current evidence remains predominantly observational and mechanistic, precision nutrition should be considered a complementary strategy requiring rigorous clinical validation.

Background Intraoperative ultrasound (IOUS) has been widely used in spinal tumor surgery. However, this imaging modality is highly operator-dependent and the available evidence regarding its applications in this field is derived predominantly from descriptive studies, while studies systematically assessing its agreement with magnetic resonance imaging (MRI) or its correlation with microsurgical findings remain scarce. The present study provides an assessment of the agreement between predurotomy IOUS and preoperative MRI in intradural extramedullary (IDEM) spinal tumor surgery based on an interobserver comparative analysis of several anatomical structures that are consistently identifiable and reproducible in this setting. In addition, corresponding microsurgical images are presented, establishing an integrated MRI–IOUS–Microsurgery correlation framework that may be valuable for both neuroradiologists and neurosurgeons. Methods A retrospective case series of patients with IDEM spinal tumors was compiled. Each case was characterised using a set of representative images depicting the same anatomical area of interest (tumor location), obtained by predurotomy IOUS, preoperative MRI and an operating microscope. Experienced neurosurgeons independently evaluated the IOUS images and MRI scans using a structured questionnaire and rated the perceived agreement on a 5–point scale by comparing several structures. Agreement between predurotomy IOUS and preoperative MRI was subsequently analysed. These structures were identified in an integrated MRI–IOUS–Microsurgery correlation framework. Results Nine patients with IDEM spinal tumors were included. A total of 768 agreement assessments were obtained, of which 579 (75.39%) were comparable. Tumor and spinal cord showed the highest levels of agreement between IOUS and MRI, followed by the subarachnoid space and dura mater, which also showed high, although somewhat lower, agreement. In contrast, pia mater and nerve roots showed the lowest levels of agreement. Compared with MRIT1c, MRIT2 demonstrated significantly higher agreement with IOUS for nerve roots, dura mater, pia mater and subarachnoid space, while there were no significant differences for tumor or spinal cord. Sagittal images achieved significantly higher agreement scores than axial images. Despite systematic differences in scoring among observers, interobserver reliability was good when ratings from four observers were averaged, with comparable reproducibility for IOUS–MRIT1c and IOUS–MRIT2. Conclusions Taking interobserver variability into account, IOUS–MRI agreement varied according to the anatomical structure evaluated, being highest for tumor and spinal cord, followed by subarachnoid space and dura mater, and lowest for pia mater and nerve roots. Sagittal images provided superior anatomical orientation compared with axial images. Interobserver reproducibility remained good despite systematic differences in individual scoring behavior.

Alzheimer’s disease (AD) has been conceptualised as a proteinopathy driven by amyloid-β plaques and hyperphosphorylated tau neurofibrillary tangles. AD should not be understood as exclusively a proteinopathy or a metabolic/redox disorder, but as a network of interacting processes in which metabolic dysfunction, mitochondrial impairment, redox dysregulation, amyloid-β, tau, neuroinflammation, metal dyshomeostasis, and regulated cell death reinforce one another. This review examines AD through a redox-metabolic framework integrating cerebral glucose metabolism, insulin signalling, mitochondrial bioenergetics, metal homeostasis, and regulated cell death. We discuss how glucose hypometabolism, impaired oxidative phosphorylation, and weakened antioxidant defences may promote reactive oxygen species production and self-reinforcing oxidative and metabolic dysfunction. We examine interactions with amyloid-β and tau pathology, glial immunometabolism, gut–brain signalling, neuroinflammation, and metal-mediated toxicity. Advances in multi-omics, blood-based metabolomic and lipidomic biomarkers, and imaging may enable earlier biological stratification. Therapeutic strategies targeting mitochondria, NRF2 signalling, metabolic dysfunction, metal dyshomeostasis, and regulated oxidative cell death are evaluated based on current evidence and their potential complementarity with amyloid-directed therapies. Although temporal relationships remain unresolved, redox-metabolic dysfunction may represent an early determinant and amplifier of neuronal vulnerability. Evidence for lecanemab and donanemab supports an integrative rather than replacement model of AD treatment. This framework may facilitate earlier diagnosis, patient stratification, and complementary disease-modifying interventions.

Alzheimer’s disease (AD) is undergoing a profound paradigm shift, transitioning from a localized, monolithic proteinopathy into a complex, multisystem disorder. This critical review synthesizes recent mechanistic, translational, and clinical insights to dismantle the traditional linear amyloid cascade hypothesis. We explore the synergistic interplay between amyloid-β (Aβ) and tau propagation, positioning chronic neuroinflammation, endolysosomal failure, and metabolic starvation—often framed as “Type 3 Diabetes”—as fundamental disease drivers. Crucially, we highlight the emerging biological bridge of CNS-PNS crosstalk, where central neurodegeneration and peripheral neuropathies are linked by systemic immune activation and microbiota–gut–brain axis dysbiosis. The recent validation of disease-modifying therapies (DMTs) confirms Aβ clearance as a viable pharmacological target; however, the marginal clinical gains and severe radiological risks, such as Amyloid-Related Imaging Abnormalities (ARIA), expose the profound limitations of monotherapy. Ultimately, we argue that isolated amyloid clearance is merely an induction phase. The future of AD therapeutics mandates a sequential combination approach—pairing early plaque debulking with lifelong metabolic and neuroimmune maintenance. Supported by scalable fluid biomarkers (e.g., plasma p-tau217) and the expanded ATN(I) framework, the field must embrace proactive precision medicine and inclusive clinical trial designs to successfully transform AD into a manageable chronic condition.

Background: Vitamin D plays an important role in immune regulation, and vitamin D deficiency has been increasingly associated with susceptibility to infection and adverse outcomes in critically ill patients. Numerous systematic reviews and meta-analyses have examined the relationship between vitamin D status, vitamin D receptor (VDR) gene polymorphisms, and sepsis; however, the evidence remains fragmented. Objective: The aim of this work was to synthesize high-level evidence on the association between vitamin D deficiency, VDR gene polymorphisms, vitamin D supplementation, and sepsis-related outcomes through a PRISMA 2020-compliant umbrella review. Methods: An umbrella review of systematic reviews and meta-analyses published between 2014 and 2025 was conducted using PubMed, PubMed Central, and journal archives. Eligible studies included adult, pediatric, and neonatal populations and evaluated sepsis incidence, mortality, disease severity, secondary outcomes, and genetic associations. Data were synthesized qualitatively due to overlap of primary studies and heterogeneity. Conceptual forest plots and funnel plots were used to summarize evidence direction and potential publication bias. Results: Nineteen systematic reviews and meta-analyses encompassing over 300 primary studies were included. Vitamin D deficiency was consistently associated with an increased risk of sepsis, higher mortality, and greater disease severity across adult and pediatric populations. Stronger associations were observed in children and neonates, including higher PRISM III scores, increased need for mechanical ventilation, and longer hospital stays. VDR gene polymorphisms were modestly but consistently associated with increased sepsis susceptibility. In contrast, vitamin D supplementation did not demonstrate a consistent reduction in sepsis risk or mortality. Conclusions: Vitamin D deficiency is a robust marker of sepsis risk, severity, and poor prognosis, whereas current evidence does not support vitamin D supplementation as an effective treatment for established sepsis.

The objective is to evaluate the parameters significantly related to calculating the power of the implanted lens and to determine the importance of different biometric, retina, and corneal aberrations variables. A retrospective cross-sectional observational study used a database of 422 patients who underwent cataract surgery at the Oftalvist Center in Almeria between January 2021 and December 2022. A random forest based on machine learning techniques was proposed to classify the importance of preoperative variables for calculating IOL power. Correlations were explored between implanted IOL power and the most important variables in random forests. The importance of each variable was analyzed using the random forest technique, which established a ranking of feature selections based on different criteria. A positive correlation was found with the random forest variables. Selection: axial length (AL), keratometry preoperative, anterior chamber depth (ACD), measured from corneal epithelium to lens, corneal diameter, lens constant, and astigmatism aberration. The variables coma aberration (p-value = 0,12) and macular thickness (p-value = 0,10) were almost slightly significant. In cataract surgery, the implanted IOL power is mainly correlated with axial length, anterior chamber depth, corneal diameter, lens constant, and preoperative keratometry. New variables such as astigmatism and anterior coma aberration and retina variables such as the preoperative central macular thickness could be included in the new generation of biometric formulas based on artificial intelligence techniques.

(1) Background: This research aimed to evaluate the changes in ganglion cell layer thickness (GCLT) after uncomplicated cataract surgery in patients without previous ocular pathology and the impact of the appearance of cystoid macular edema on the GCLT and visual acuity. (2) Methods: The evaluation of 174 patients was performed with the indication of uncomplicated cataract surgery. The variables analyzed were demographic data, best-corrected visual acuity (BCVA), cataract type and OCT (Optical Coherence Tomography) measurements of central macular thickness (CMT), and the presence of cysts and GCLT preoperatively and one day, one and three months after surgery. (3) Results: There was a relationship between the postoperative increase in retinal GCLT and BCVA after uncomplicated cataract surgery. The presence of microcysts reduced the thickness of the GCL, which is significantly related to the loss of BCVA. The appearance of cystoid macular edema one month after surgery was also related to the preoperative CMT. There was a statistically significant decrease in preoperative GCL but a statistically significant increase in preoperative CMT in patients with microcysts one-month post-surgery. (4) Conclusions: There is a relationship between postoperative retinal GCLT and BCVA after uncomplicated cataract surgery. The presence of microcysts significantly reduces the thickness of the GCL, which is significantly related to the loss of BCVA.

In the post-restrictions COVID-19 period, the incidence of bronchiolitis in infants has increased considerably. Several scores determine the degree of severity of the bronchiolitis episode, but few are clinician-friendly. The main aim of this research was to find the easy-to-use score that most accurately estimated the severity of patients’ infections according to their clinical situations and most accurately predicted the need for hospital admission. An observational cross-sectional study was performed in a reference pediatric hospital during the post-restrictions period of the COVID-19 pandemic (2021 and 2022). A comparison was made between the severity estimate provided by five international acute bronchiolitis scales and the clinical severity of the acute bronchiolitis episode. Three hundred and seventy-seven patients participated in the investigation, with a mean age of 5.68 months; 68.7% of the participants had a mild episode of bronchiolitis, 24.5% had a moderate episode, and 6.9% had a severe episode. The severity estimated by the Tal scale modified by McCallum showed a statistically significant correlation with the clinical severity established by clinical criteria (0.836; p < 0.001). It showed a high correlation with other international scores, such as the Wang score (0.820; p < 0.05) and the Wood–Downes–Ferrés score (0.936; p < 0.001). In the multivariate analysis, the constituent variables of the modified Tal score appeared in the final model that predicts the need for hospital admission. In the context of increased incidence after COVID-19, the Tal score modified by McCallum is an easy-to-use measuring instrument that presents an excellent concordance with the clinical severity estimated at first care contact. It also offers a more significant prediction of the need for hospital admission.