Search Results (1,334)

Alzheimer’s disease (AD) is the leading cause of dementia worldwide and is becoming one of the most morbid diseases of this century. Recently, ocular research in AD has gained significance, as the eye, due to its close relationship with the brain, can reflect the presence of neurological disorders. Several studies have reported alterations in various ocular structures in AD, ranging from tear fluid to the retina. These changes, particularly in the retina and the optic nerve, along with cerebral atrophy affecting visual brain areas, may lead to visual dysfunctions. This narrative review summarizes and critically examines current evidence on these impairments and explores their possible underlying mechanisms. A decrease in visual acuity, contrast sensitivity, and color vision has been observed, primarily associated with retinal ganglion cell loss or damage. Furthermore, alterations in the visual field, ocular motility, and visual perception have been recorded, mainly resulting from cortical changes. These optical parameters frequently correlate with patients’ cognitive status. In conclusion, these findings highlight the importance of developing strategies to preserve visual function in these patients, helping to prevent further deterioration in their quality of life, and emphasize the potential of visual function assessment as a tool for diagnosis or predicting AD progression. Full article

Stroke is a leading global cause of mortality and long-term disability, with cerebral edema constituting a major contributor to early neurological deterioration and poor outcomes. Aquaporin-4 (AQP4), the predominant water channel in the central nervous system, plays a paradoxical role in stroke-related brain edema, facilitating both the formation and clearance of excess fluid depending on the pathological context. This review explores the biphasic function of AQP4 across cytotoxic and vasogenic edema, emphasizing its dynamic regulation, subcellular localization, and implications for therapeutic intervention. Evidence from rodent models shows that AQP4 exacerbates cytotoxic edema in acute ischemia by promoting intracellular water influx into astrocytes, whereas in vasogenic edema, it supports fluid reabsorption and glymphatic clearance, thereby alleviating brain swelling. Human studies corroborate AQP4 upregulation in infarcted regions and suggest a potential role for AQP4 polymorphisms and circulating levels as biomarkers of stroke severity and outcome, although larger cohorts and more robust methodological designs are needed. This review also discusses emerging pharmacological strategies to modulate AQP4 activity, including inhibitors, trafficking modulators, and gene-targeted delivery systems, while highlighting challenges in achieving phase-specific modulation. Given its central role in both injury and recovery, AQP4 emerges as a promising yet complex therapeutic target for personalized management of stroke-induced brain edema. Future directions include real-time imaging of AQP4 function, genotype-stratified clinical trials, and integration of AQP4 modulation with current stroke treatment protocols. Full article

Background: Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumour, associated with poor survival outcomes and significant clinical challenges. Conventional diagnostic methods, including MRI, CT, and histopathological analysis of tissue biopsies, are limited by their inability to reliably distinguish treatment effects from true tumour progression, often resulting in misdiagnosis and delayed intervention. Repeated tissue biopsies are also invasive and unsuitable for longitudinal monitoring. Liquid biopsy, a minimally invasive approach analysing tumour-derived material in biofluids such as blood and cerebrospinal fluid (CSF), offers a promising alternative. This review aims to evaluate current evidence on circulating biomarkers including circulating tumour cells (CTCs), circulating tumour DNA (ctDNA), microRNAs (miRNAs), extracellular vesicles (EVs), and proteins in GBM diagnosis and monitoring, and to assess the potential role of artificial intelligence (AI) in enhancing their clinical application. Methods: A narrative synthesis of the literature was undertaken, focusing on studies that have investigated blood- and CSF-derived biomarkers in GBM patients. Key aspects evaluated included biomarker biology, detection techniques, diagnostic and prognostic value, current technical challenges, and progress towards clinical translation. Studies exploring AI and machine learning (ML) approaches for biomarker integration and analysis were also reviewed. Results: Liquid biopsy enables repeated and minimally invasive sampling of tumour-derived material, reflecting the genetic, epigenetic, proteomic, and metabolomic landscape of GBM. Although promising, its translation into routine clinical practice is hindered by the low abundance of circulating biomarkers and lack of standardised collection and analysis protocols. Evidence suggests that combining multiple biomarkers improves sensitivity and specificity compared with single-marker approaches. Emerging AI and ML tools show significant potential for improving biomarker discovery, integrating multi-omic datasets, and enhancing diagnostic and prognostic accuracy. Conclusions: Liquid biopsy represents a transformative tool for GBM management, with the capacity to overcome limitations of conventional diagnostics and provide real-time insights into tumour biology. By integrating multiple circulating biomarkers and leveraging AI-driven approaches, liquid biopsy could enhance diagnostic precision, enable dynamic disease monitoring, and improve clinical decision-making. However, large-scale validation and standardisation are required before routine clinical adoption can be achieved. Full article

Background/Objectives: Gut microbial dysbiosis, leaky gut, and increased transepithelial translocation of commensal bacteria have been documented in multiple sclerosis (MS). Intrathecal IgGs specific for Akkermansia muciniphila, a gut bacterium, are increased in patients with MS and associated with clinical disability. Our objective here was to explore the putative involvement of intrathecal anti-A. muciniphila IgG in MS pathogenesis by characterizing patients with different anti-A. muciniphila IgG indices. Methods: Serum and intrathecal IgG specific for A. muciniphila and other gut bacteria, as well as routine cerebrospinal fluid (CSF) parameters, were measured in 61 patients with MS. Examination of these patients included immunophenotyping of CSF-infiltrating and paired circulating lymphocytes, intrathecal markers of neurodegeneration and inflammation, and a detailed characterization of demographic, clinical, and magnetic resonance imaging (MRI) features. Results: Plasma blasts (p < 0.01), B cells (p < 0.01), and Th2 cells (p < 0.01), which might be involved in antibody production, were increased in the CSF of these patients, as well as blood pro-inflammatory Th17 cells (p < 0.05). Anti-A. muciniphila IgG indices were negatively associated with blood-brain barrier (BBB) permeability and circulating monocytes (p < 0.001), and positively with brain lesion load (p < 0.01). Conclusions: The differences between patients with low and high anti-A. muciniphila IgG indexes regarding BBB permeability, CSF cell infiltrates, and pro-inflammatory peripheral immune cells, as well as imaging features, support a role of anti-A. muciniphila immune response in MS pathogenesis. Full article

Thirst is usually characterized as an unpleasant sensation provoking drinking of water. The purpose of the present review is to draw attention to the importance of thirst in overall regulation of body fluid homeostasis in health and pathology. Intensity of thirst is determined by signals generated in multiple groups of osmosensitive neurons engaged in dipsogenic and antidipsogenic activities, which are located in the brain cortex, the insula, the amygdala, the median preoptic area, the hypothalamic nuclei and the organum vasculosum laminae terminalis. Water ingestion is also influenced by signals generated in the cardiovascular system, the gastrointestinal system, the pancreas, the liver and the kidney and by changes of body temperature. Regulation of thirst engages the autonomic nervous system and several neuroactive factors synthetized in the brain and the peripheral organs. Among them are components of the renin–angiotensin system, vasopressin, atrial natriuretic peptide, cholecystokinin, ghrelin, gaseous transmitters, cytokines and prostaglandins. Experimental studies provide evidence that elevation of fluid osmolality, which is the most frequent cause of thirst, influences function of the voltage-gated sodium channel and calcium-dependent kinase II subunit alpha. Regulation of thirst may be inappropriate in old age and under some pathological conditions including infections, heart failure, diabetes insipidus, diabetes mellitus, and psychogenic disorders. The molecular background of the abnormal regulation of thirst in the clinical disorders is not yet sufficiently recognized and requires further examination. Full article

Background/Objectives: Previous magnetic resonance imaging (MRI) investigations reported brain alterations in anorexia nervosa restricting type (AN-R); however, the number of existing structural neuroimaging studies in the developmental age is limited. Here, we analyzed the volumetric brain differences between adolescent patients with AN-R and control peers, and possible correlations between brain volumes and clinical features. Methods: The sample comprised 47 adolescent females with AN-R (mean age: 15.0 years, SD = 1.4) who underwent structural MRI within one month of admission to a tertiary care university hospital, and 39 typically developing controls matched for sex and age. The patients were clinically characterized by standardized interviews/questionnaires. Using the voxel-based morphometry (VBM) technique, possible significant volumetric brain differences between the two groups were analyzed. Moreover, correlations between altered brain regions and clinical (i.e., body mass index (BMI) and disease duration) or psychopathological variables were investigated. Results: An overall reduction in gray matter (GM) volume with a concomitant increase in cerebrospinal fluid (CSF) is observed in AN-R patients; these alterations correlate with a lower BMI. The reduction in GM volume affects the frontal and parietal regions involved in the cognitive processes that underlie and sustain the AN-R clinical features. Conclusions: These results add to the current knowledge of the AN-R pathophysiology and pave the way for the development of brain imaging biomarkers for AN in the developmental age. Full article

(1) Background: Choroid plexus papillomas (CPPs) are rare brain tumors that tend to occur in very young children. Mechanisms of CPP development remain unelucidated. Separately, the process of angiogenesis has been implicated in other primary brain tumors. We hypothesize that angiogenesis is a hallmark of CPP biology. This study aims to identify and validate angiogenic factors in CPPs. (2) Methods: Cerebrospinal fluid (CSF) and CPP tumor samples are collected. A multiplex immunoassay panel is used to identify differentially expressed cytokines in the CSF samples. Concurrently, patient-derived primary cell cultures and their supernatants are derived from CPP samples. Targeted proteome blot arrays and human umbilical vein endothelial cell (HUVEC) angiogenesis assays are used for validation studies. (3) Results: CSF profiling showed higher expressions of VEGF-A, MCP-1, MMP-1, TNF-α, and CD40L in CPP patient samples versus non-tumor controls. Next, assessment via online protein–protein network platforms reports that these cytokines are associated with endothelial cell regulation. Using an angiogenesis-focused approach, CPP-derived cell lines and supernatants showed similarly higher expressions of VEGF, MCP-1, and MMP-1. Next, sprouting of nodes and tubule formation were observed in HUVEC angiogenesis assay cultures when conditioned CPP cell culture media was added. (4) Conclusions: This proof-of-concept study demonstrates potential to explore angiogenesis in CPP. Full article

Alzheimer’s disease (AD) affects approximately 50 million people worldwide, with women comprising two-thirds of those affected. Despite this disproportionate impact, the sex-specific pathological mechanisms underlying AD in women remain poorly understood, and female-specific biomarkers have been significantly understudied. This critical knowledge gap requires focused research to improve diagnostic and therapeutic approaches for women with AD. In this review, we systematically examine the pathological mechanisms underlying AD in women, including sex-related differences in inflammation, autophagy, and metabolic dysfunction. We further explore microRNA (miRNA) expression patterns and evaluate miRNA candidates as potential biomarkers for AD in women based on current literature. Through this analysis, we identified approximately 20 miRNA candidates derived from diverse human samples, including brain tissue, blood, and cerebrospinal fluid, in multiple independent studies. These candidates demonstrate the potential for developing accessible, non-invasive biomarkers, particularly those identified in blood and cerebrospinal fluid. However, the limited overlap between studies highlights that female-specific miRNA biomarker research for AD remains in its early discovery phase, emphasizing the urgent need for large-scale validation studies and standardized methodological approaches to advance this promising field for clinical application. Full article

Cardiorenal syndrome (CRS) is a term used to describe the combined dysfunction of the heart and kidneys. This complex disorder is widely acknowledged to be challenging in both its diagnosis and management, and this is the case particularly in the elderly population, due to multi-morbidity, polypharmacy, and age-related physiological changes. Given advancements in medicine and more prolonged cumulative exposure to risk factors in the elderly population, it is likely that the prevalence of chronic kidney disease (CKD) and heart failure (HF) will continue to rise going forward. Hence, understanding the mechanisms involved in the development of CRS is paramount. There are five different CRS types—they are categorised depending on the primary organ involved the acuity of disease. The pathophysiological process behind CRS is complex, involving the interplay of many processes including hemodynamic changes, neurohormonal activation, inflammation, oxidative stress, and endothelial dysfunction and vascular stiffness. The numerous diagnostic and management challenges associated with CRS are significantly further exacerbated in an elderly population. Biomarkers used to aid the diagnosis of CRS, such as serum creatinine and brain natriuretic peptide (BNP), can be challenging to interpret in the elderly population due to age-related renal senescence and multiple comorbidities. Polypharmacy can contribute to the development of CRS and therefore, before initiating treatment, coordinating a patient-centred, multi-speciality, holistic review to assess potential risks versus benefits of prescribed treatments is crucial. The overall prognosis of CRS in the elderly remains poor. Treatments are primarily directed at addressing the sequelae of the underlying aetiology, which often involves the removal of fluid through diuretics or ultrafiltration. Careful considerations when managing elderly patients with CRS is essential due to the high prevalence of frailty and functional decline. As such, in these patients, early discussions around advance care planning should be prioritised. Full article

Purpose: Our understanding of the influence of preterm birth and related perinatal exposures on early brain development is limited, hampering personalized optimization of neuroprotective strategies. This study assesses the effect of gestational age (GA) at birth on brain volumes at term-equivalent age (TEA) in infants without overt brain injury born across the GA spectrum. Methods: A cohort of infants born across the GA spectrum (25–40 weeks’ gestation) underwent 3T brain MRI around TEA (40–46 weeks postmenstrual age). Eight brain regions, intracranial and total tissue volumes were segmented using MANTiS (morphologically adaptive neonatal tissue segmentation toolbox). Segmentations were visually quality-checked and excluded if segmentation failed. Absolute TEA volume in relation to GA was assessed using univariate and multivariate (correction for postmenstrual age) linear regression analysis. Statistical significance was set at p < 0.05. Post hoc scatter plots of brain volumes relative to intracranial volumes were created. Results: Fifty infants were included (mean GA = 35.0 [SD = 3.3, range = 25.7–40.1] weeks). A higher GA at birth was significantly related to lower cerebrospinal fluid (p = 0.004) and amygdala (p = 0.02) volumes; no significant relation was found between GA and other volumes. Post hoc analyses showed positive trends between GA and several brain structures, including total brain tissue, cortical gray matter, deep gray matter, hippocampus, cerebellum and brainstem volumes. Conclusions: Our results suggest that GA has an effect on TEA brain volumes that is independent of brain lesions, with lower GA being associated with smaller brain tissue volumes and significantly larger cerebrospinal fluid volume. Preterm birth and related exposures may thus affect early brain growth and contribute to neurodevelopmental challenges encountered by preterm-born children. Full article

Background and Objectives: The objective of this research is to make a comparative evaluation of the correlation between the volumetric examination of subcortical cerebral regions and white matter hyperintensities classified according to the Fazekas scoring system. Materials and Methods: A total of 236 cases with cranial MRI studies were retrospectively analyzed. This study included patients aged over 45 years who had white matter hyperintensities and who did not have a prior stroke diagnosis. White matter hyperintensities were evaluated in axial FLAIR images according to Fazekas’s grading scale. Patients with Fazekas 0 and 1 were grouped in group 1 and the patients with Fazekas 2 and 3 were grouped in group 2. MRI data processing and subcortical volumetric analyses were performed using the volBrain MRI brain volumetry system. Results: There were statistically significant differences between groups 1 and 2 in terms of cerebrospinal fluid total brain white and gray matter (p < 0.001), total brain white and gray matter (p = 0.009), total cerebrum (p < 0.001), accumbens (p < 0.001), thalamus (p < 0.001), frontal lobe (p < 0.001), parietal lobe (p < 0.001), and lateral ventricle (p < 0.001) volumes. Conclusions: Our study finds a strong link between white matter hyperintensity burden and brain atrophy. This includes volume reductions in total brain white and gray matter, frontal and parietal lobe atrophy, increased cerebrospinal fluid (CSF), and atrophy in specific brain regions such as the accumbens and thalamus. Full article

Background: Secondary (nosocomial) bacterial meningitis remains a serious problem in patients with severe brain damage. The aim of this study was to assess the differences in the aromatic metabolites of tryptophan, phenylalanine, and tyrosine, in serum and cerebrospinal fluid (CSF) samples collected simultaneously from patients with long-term sequelae of severe brain damage with suspected secondary bacterial meningitis. Methods: Group I included 16 paired serum and CSF samples from patients (N = 11) without secondary bacterial meningitis; group II included 13 paired serum and CSF samples from patients (N = 4) with secondary bacterial meningitis. Results: The median concentrations of serum 5-hydroxyindole-3-acetic, CSF 4-hydroxyphenyllactic (p-HPhLA), CSF 4-hydroxyphenylacetic, CSF phenyllactic, and indole-3-lactic acids in serum and CSF were statistically higher in group II compared to group I (p-value ≤ 0.03), while 4-hydroxyphenylpropionic and indole-3-acetic in serum were lower in group II compared to group I (p-value = 0.04). In group I, p-HPhLA serum concentrations were greater than or equal to its CSF concentrations in 14 paired samples; in group II, p-HPhLA concentrations in serum were lower than in CSF in all paired samples. Conclusions: The obtained results demonstrate the differences in the profile of aromatic metabolites in serum and CSF and may confirm the hypothesis of the p-HPhLA microbial origin in the CSF of patients with secondary bacterial meningitis. Full article

Background/Objectives: Multimodal large language models (LLMs) are increasingly used in radiology. However, their ability to recognize fundamental imaging features, including modality, anatomical region, imaging plane, contrast-enhancement status, and particularly specific magnetic resonance imaging (MRI) sequences, remains underexplored. This study aims to evaluate and compare the performance of three advanced multimodal LLMs (ChatGPT-4o, Claude 4 Opus, and Gemini 2.5 Pro) in classifying brain MRI sequences. Methods: A total of 130 brain MRI images from adult patients without pathological findings were used, representing 13 standard MRI series. Models were tested using zero-shot prompts for identifying modality, anatomical region, imaging plane, contrast-enhancement status, and MRI sequence. Accuracy was calculated, and differences among models were analyzed using Cochran’s Q test and McNemar test with Bonferroni correction. Results: ChatGPT-4o and Gemini 2.5 Pro achieved 100% accuracy in identifying the imaging plane and 98.46% in identifying contrast-enhancement status. MRI sequence classification accuracy was 97.7% for ChatGPT-4o, 93.1% for Gemini 2.5 Pro, and 73.1% for Claude 4 Opus (p < 0.001). The most frequent misclassifications involved fluid-attenuated inversion recovery (FLAIR) sequences, often misclassified as T1-weighted or diffusion-weighted sequences. Claude 4 Opus showed lower accuracy in susceptibility-weighted imaging (SWI) and apparent diffusion coefficient (ADC) sequences. Gemini 2.5 Pro exhibited occasional hallucinations, including irrelevant clinical details such as “hypoglycemia” and “Susac syndrome.” Conclusions: Multimodal LLMs demonstrate high accuracy in basic MRI recognition tasks but vary significantly in specific sequence classification tasks. Hallucinations emphasize caution in clinical use, underlining the need for validation, transparency, and expert oversight. Full article

Lung transplantation remains the standard of care for end-stage lung disease, yet a persistent gap exists between donor lung availability and growing clinical demand. Expanding the donor pool and optimising donor lung management are therefore critical priorities. However, no universally accepted management protocols are currently in place. This narrative review examines evidence-based strategies to improve lung utilisation across three donor categories: donors after brain death (DBD), controlled donors after circulatory death (cDCD), and uncontrolled donors after circulatory death (uDCD). A systematic literature search was conducted to identify interventions targeting lung preservation and function, including protective ventilation, recruitment manoeuvres, fluid and hormonal management, and ex vivo lung perfusion (EVLP). Distinct pathophysiological mechanisms—sympathetic storm and systemic inflammation in DBD, ischaemia–reperfusion injury in cDCD, and prolonged warm ischaemia in uDCD—necessitate tailored approaches to lung preservation. In DBD donors, early application of protective ventilation, bronchoscopy, and infection surveillance is essential. cDCD donors benefit from optimised pre- and post-withdrawal management to mitigate lung injury. uDCD donor lungs, uniquely vulnerable to ischaemia, require meticulous post-mortem evaluation and preservation using EVLP. Implementing structured, evidence-based lung management strategies can significantly enhance donor lung utilisation and expand the transplantable organ pool. The integration of such practices into clinical protocols is vital to addressing the global shortage of suitable lungs for transplantation. Full article

Alzheimer’s Disease (AD) is a multifactorial process. Amyloid plaque formation constitutes the main characteristic of the disease. Despite the identification of numerous factors associated with AD, the mechanism remains unclear in several aspects. Disturbances in intestinal and blood–brain barrier (BBB) penetration, observed in AD, may facilitate immunologic response to food-derived antigens. In the present study, antibodies against egg albumin, bovine-casein, and N-Glycolyl-Neuraminic acid (Neu5Gc) were measured in the cerebrospinal fluid (CSF) and serum of the patients using an enzyme-linked immunosorbent assay (ELISA). Zero anti-Neu5Gc and low concentrations of anti-casein antibodies were detected. Increased anti-native egg albumin antibodies were present in the serum of patients of all stages with 65% positivity (p < 0.001) in mild disease and a higher percentage in females (81.9%, p < 0.001). Lower serum positivity to anti-denatured egg albumin antibodies was observed, showing a gradual increase with severity and higher prevalence also in females. In the CSF, anti-native and anti-denatured egg albumin antibodies were mainly observed in severely ill patients with accumulative positivity to either antigen, reaching 61.8% in severe vs. 15% in mild disease (p < 0.001). Increased values were mainly observed in males. Anti-egg albumin antibodies may be implicated in the disease mechanism through sequence/structural similarity with human proteins, mainly serpins, and it would be worth consideration in further investigations and therapeutic strategies. Full article