Biomarkers in traumatic brain injury (TBI): a review

Clearance of Cell-Free DNA: A Novel Target for Therapeutic Utilization in Multiple Systemic Disorders

Cell-free DNA (cfDNA) holds significant promise for diagnostic and therapeutic advancements in medicine. This review delineates the utility of cfDNA in diagnostics and its therapeutic potential through clearance mechanisms for an array of diseases. Damage-associated molecular patterns (DAMPs) are endogenous molecules released by host cells during stress, or injury. As a trigger for inflammatory responses via damage-associated molecular patterns (DAMPs), cfDNA's removal via nanotechnological approaches can attenuate inflammation and promote tissue repair. While the application of cfDNA clearance is particularly auspicious in cancer, sepsis, and inflammatory conditions, it is confronted with challenges including toxicity, specificity, and the rigors of clinical trial validation. Collectively, this review delineates novel therapeutic targets to inform the development of innovative treatment strategies.

CRISPR/Cas9-Based therapeutics as a promising strategy for management of Alzheimer's disease: progress and prospects

CRISPR/Cas9 technology has revolutionized genetic and biomedical research in recent years. It enables editing and modulation of gene function with an unparalleled precision and effectiveness. Among the various applications and prospects of this technology, the opportunities it offers in unraveling the molecular underpinnings of a myriad of central nervous system diseases, including neurodegenerative disorders, psychiatric conditions, and developmental abnormalities, are unprecedented. In this review, we highlight the applications of CRISPR/Cas9-based therapeutics as a promising strategy for management of Alzheimer's disease and transformative impact of this technology on AD research. Further, we emphasize the role of CRISPR/Cas9 in generating accurate AD models for identification of novel therapeutic targets, besides the role of CRISPR-based therapies aimed at correcting AD-associated mutations and modulating the neurodegenerative processes. Furthermore, various delivery systems are reviewed and potential of the non-viral nanotechnology-based carriers for overcoming the critical limitations of effective delivery systems for CRISPR/Cas9 is discussed. Overall, this review highlights the promise and prospects of CRISPR/Cas9 technology for unraveling the intricate molecular processes underlying the development of AD, discusses its limitations, ethical concerns and several challenges including efficient delivery across the BBB, ensuring specificity, avoiding off-target effects. This article can be helpful in better understanding the applications of CRISPR/Cas9 based therapeutic approaches and the way forward utilizing enormous potential of this technology in targeted, gene-specific treatments that could change the trajectory of this debilitating and incurable illness.

Molecular Biomarkers Associated with Traumatic Brain Injury Outcome in Individuals of Black Racial Identity or African Ancestry: A Narrative Review

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide and a major global health concern. In the United States, individuals of Black or African American racial identity experience disproportionately higher rates of TBI and suffer from worse postinjury outcomes. Contemporary research agendas have largely overlooked or excluded Black populations, resulting in the continued marginalization of Black patient populations in TBI studies, thereby limiting the generalizability of ongoing research to patients in the United States and around the world. This review aims to highlight what is currently known, and identify knowledge gaps, in research on molecular biomarkers associated with TBI in Black populations. A PubMed literature search was conducted to identify studies that investigate molecular biomarkers associated with TBI outcomes that include participants of Black racial identity and those of African ancestry. Studies identified for this review investigate biomarkers associated with TBI outcomes through a lens that specifically examines race, ethnicity, or ancestry. Most studies focused on blood- or cerebrospinal fluid-derived protein biomarkers. Studies identified statistical variation in S100ß, ubiquitin C-terminal hydrolase-L1, amyloid-ß, and tau across participant race, either at baseline or following TBI. Additionally, several studies identified genetic polymorphisms associated with TBI outcomes related to apolipoprotein E, ANKK1, and COMT polymorphism and TBI outcome and identified allele frequency variation across population ancestry. The role of race and ancestry on biomarkers associated with TBI outcome remains indeterminate and subsequent work is still required to understand the implications for patients with TBI.

Metabolomic in severe traumatic brain injury: exploring primary, secondary injuries, diagnosis, and severity

BACKGROUND

Traumatic brain injury (TBI) is a major public health concern worldwide, contributing to high rates of injury-related death and disability. Severe traumatic brain injury (sTBI), although it accounts for only 10% of all TBI cases, results in a mortality rate of 30-40% and a significant burden of disability in those that survive. This study explored the potential of metabolomics in the diagnosis of sTBI and explored the potential of metabolomics to examine probable primary and secondary brain injury in sTBI.

METHODS

Serum samples from 59 adult patients with sTBI and 35 age- and sex-matched orthopedic injury controls were subjected to quantitative metabolomics, including proton nuclear magnetic resonance (1H-NMR) and direct infusion/liquid chromatography-tandem mass spectrometry (DI/LC-MS/MS), to identify and quantify metabolites on days 1 and 4 post-injury. In addition, we used advanced analytical methods to discover metabo-patterns associated with sTBI diagnosis and those related to probable primary and secondary brain injury.

RESULTS

Our results showed different serum metabolic profiles between sTBI and orthopedic injury (OI) controls, with significant changes in measured metabolites on day 1 and day 4 post-brain injury. The number of altered metabolites and the extent of their change were more pronounced on day 4 as compared to day 1 post-injury, suggesting an evolution of mechanisms from primary to secondary brain injury. Data showed high sensitivity and specificity in separating sTBI from OI controls for diagnosis. Energy-related metabolites such as glucose, pyruvate, lactate, mannose, and polyamine metabolism metabolites (spermine and putrescine), as well as increased acylcarnitines and sphingomyelins, occurred mainly on day 1 post-injury. Metabolites of neurotransmission, catecholamine, and excitotoxicity mechanisms such as glutamate, phenylalanine, tyrosine, and branched-chain amino acids (BCAAs) increased to a greater degree on day 4. Further, there was an association of multiple metabolites, including acylcarnitines (ACs), lysophosphatidylcholines (LysoPCs), glutamate, and phenylalanine, with injury severity at day 4, while lactate, glucose, and pyruvate correlated with injury severity on day 1.

CONCLUSION

The results demonstrate that serum metabolomics has diagnostic potential for sTBI and may reflect molecular mechanisms of primary and secondary brain injuries when comparing metabolite profiles between day 1 and day 4 post-injury. These early changes in serum metabolites may provide insight into molecular pathways or mechanisms of primary injury and ongoing secondary injuries, revealing potential therapeutic targets for sTBI. This work also highlights the need for further research and validation of sTBI metabolite biomarkers in a larger cohort.

Advancements in diagnosing Post-concussion Syndrome: insights into epidemiology, pathophysiology, neuropathology, neuroimaging, and salivary biomarkers

Post-Concussion Syndrome (PCS) represents a complex constellation of symptoms that persist following a concussion or mild traumatic brain injury (mTBI), with significant implications for patient care and outcomes. Despite its prevalence, diagnosing PCS presents considerable challenges due to the subjective nature of symptoms, the absence of specific diagnostic tests, and the overlap with other neurological and psychiatric conditions. This review explores the multifaceted diagnostic challenges associated with PCS, including the heterogeneity of symptom presentation, the limitations of current neuroimaging techniques, and the overlap of PCS symptoms with other disorders. We also discuss the potential of emerging biomarkers and advanced imaging modalities to enhance diagnostic accuracy and provide a more objective basis for PCS identification. Additionally, the review highlights the importance of a multidisciplinary approach in the diagnosis and management of PCS, integrating clinical evaluation with innovative diagnostic tools to improve patient outcomes. Through a comprehensive analysis of current practices and future directions, this review aims to shed light on the complexities of PCS diagnosis and pave the way for improved strategies in the identification and treatment of this condition.

The Pathophysiology of Traumatic Brain Injuries and the Rationale Behind Creatine Supplementation as a Potential Therapy: A Review

Traumatic brain injuries (TBI) are detrimental to the brain in a variety of ways. Mild traumatic brain injuries (mTBI) are concussions; these are common events that disrupt typical brain functioning and send millions of patients to seek acute care each year globally. Despite the frequency of mTBIs, clinicians have few tools, pharmacologic and nonpharmacologic, to promote recovery and alleviate symptoms. After a TBI, complex biomolecular signaling, diffuse axonal stretching, and glutamate excitotoxicity occur, along with other pathological sequelae. Creatine has been shown to improve cognitive functioning in healthy adults. Burgeoning research is providing evidence that creatine may enhance recovery from TBI, as it directly targets derangements from such trauma.

Brain white matter damage biomarkers

White matter (WM), constituting nearly half of the human brain's mass, is pivotal for the rapid transmission of neural signals across different brain regions, significantly influencing cognitive processes like learning, memory, and problem-solving. The integrity of WM is essential for brain function, and its damage, which can occur due to conditions such as multiple sclerosis (MS), stroke, and traumatic brain injury, results in severe neurological deficits and cognitive decline. The primary objective of this book chapter is to discuss the clinical significance of fluid biomarkers in assessing WM damage within the central nervous system (CNS). It explores the biological underpinnings and pathological changes in WM due to various neurological conditions and details how alterations can be detected and quantified through fluid biomarkers. By examining biomarkers like Myelin Basic Protein (MBP), Neurofilament light chain (NFL), and others, the chapter highlights their role in enhancing diagnostic precision, monitoring disease progression, and guiding therapeutic interventions, thus providing crucial insights into maintaining WM integrity and preventing cognitive and physical disabilities.

Exploring New and Promising Genetic Biomarkers for Evaluating Traumatic Brain Injuries: A Case-Control Study

Traumatic brain injury (TBI) is a common cause of morbidity and death in all age groups, with an estimated 50 million people having brain injury due to trauma each year. Accurate blood-based biomarkers are needed to assist with diagnosis of patients across the spectrum of time and severity. Our objectives were to explore the diagnostic precision of time- and severity- related four blood-based biomarkers: AKT3, GSK-3β, hsa-miR-16-5p, and MALAT-1 for TBI for the purpose of diagnosis, prognosis, and follow-up. 40 samples were recruited as the following: 30 TBI patients and 10 healthy volunteers as controls with matched age and sex. They were divided according to the Glasgow Coma Scale into mild (mTBI), moderate (modTBI), and severe(sTBI) TBI. Blood samples were withdrawn at entry, and after 5 and 30 days, RT-PCR was used for measuring the expression level. The results showed upregulated expression levels of AKT3, hsa-miR-16-5p and significantly downregulated expression levels of GSK-3β in TBI patients compared to controls at all timings measured. mTBI patients showed a higher expression level of hsa-miR-16-5p compared with modTBI, and sTBI patients. MALAT-1 level showed a significant increase in severe cases only. We concluded that AKT3, hsa-miR-16-5p, and GSK-3β are excellent diagnostic biomarkers in TBI patients at initial assessment, as well as at 5 and 30 days following the injury. Moreover, MALAT-1 had good diagnostic value in sTBI patients, and its prognostic value extends to 30 days. GSK-3β was an excellent biomarker for detecting mTBI.

Biomarkers and Endophenotypes of Post-traumatic Headaches

PURPOSE OF REVIEW

To review existing literature on biomarkers for post-traumatic headache (PTH).

RECENT FINDINGS

Preclinical models and clinical findings have started to elucidate the biology that underlies PTH. Traumatic brain injury results in ionic flux, glutamatergic surge, and activation of the trigeminal cervical complex resulting in the release of pain neuropeptides. These neuropeptides, including calcitonin gene-related peptide (CGRP) and pituitary adenylate cyclase-activating polypeptide (PACAP), play a key role in the pathophysiology of migraine and other primary headache disorders. Only two studies were identified that evaluated CGRP levels in PTH. Neither study found a consistent relationship between CGRP levels and PTH. One study did discover that nerve growth factor (NGF) was elevated in subjects with PTH. There is no conclusive evidence for reliable blood-based biomarkers for PTH. Limitations in assays, collection technique, and time since injury must be taken into account. There are multiple ideal candidates that have yet to be explored.

Performance of the neutrophil-lymphocyte ratio as a predictor of severity and mortality in children and adolescents with traumatic brain injury

PURPOSE

An inflammatory cascade associated with the systemic neutrophil response can be triggered after traumatic brain injury (TBI), causing neuronal dysfunction, which is considered to be related to the prognosis of the victims. The scope of this research is to identify the performance of the neutrophil-lymphocyte ratio (NLR) as a predictor of prognosis considering TBI severity and death as outcomes in a group of pediatric patients.

METHODS

We retrospectively evaluated NLR through a consecutive review of the medical records (cross-sectional study) of children and adolescents aged < 17 years victims of TBI. To determine the highest NLR value identified as a predictor, different cutoff points were tested for each outcome. The cutoff points were defined based on the area under curve (AUC) of the receiver operating characteristic (ROC).

RESULTS

Among the 82 children with TBI included in the sample, the performance of AUC-ROC was 0.72 when evaluating NLR as a predictor of TBI severity, with NLR cutoff point of 3, and 0.76 when considering mortality as the outcome, with an increase in the cutoff point to 11.

CONCLUSION

NLR can be considered a biomarker of brain injury in children and adolescent victims of TBI. Patients with NLR ≥ 3 had a fivefold higher probability of severe TBI and patients with NLR ≥ 11 experienced a ninefold higher risk of death.

Traumatic Brain Injury as a Public Health Issue: Epidemiology, Prognostic Factors and Useful Data from Forensic Practice

Traumatic brain injury (TBI) represents a major public health problem, being a leading cause of disability and mortality among young people in developed countries. Head trauma occurs across all age groups, each experiencing consistently high rates of mortality and disability. This review aims to present an overview of TBI epidemiology and its socioeconomic impact, alongside data valuable for prevention, clinical management, and research efforts. Methods: A narrative review of TBI was performed with a particular focus on forensic pathology and public health. In fact, this review highlighted the economic and epidemiological aspects of TBI, as well as autopsy, histology, immunohistochemistry, and miRNA. Results: These data, together with immunohistochemical markers, are crucial for histopathological diagnosis and to determine the timing of injury onset, a fundamental aspect in forensic pathology practice. There is compelling evidence that brain injury biomarkers may enhance predictive models for clinical and prognostic outcomes. By clarifying the cause of death and providing details on survival time after trauma, forensic tools offer valuable information to improve the clinical management of TBI and guide preventive interventions. Conclusions: TBI is one of the most common causes of death today, with high costs for health care spending. Knowing the different mechanisms of TBI, reduces health care costs and helps improve prognosis.

Accuracy of acute hyperglycemia as a biomarker of severe brain damage in children with traumatic brain injury

PURPOSE

Biomarkers are substances measured at the systemic level to evaluate organic responses in certain situations, establishing diagnoses, disease staging, and prognosis. Blood glucose is a biomarker recognized as a predictor of prognosis in children victims of traumatic brain injury (TBI). The scope of this study was to identify the accuracy of blood glucose as a biomarker of severe brain injury.

METHODS

A retrospective analytical study was conducted through the consecutive review of medical records of children and teenage victims of TBI who underwent neurological surgery between 2016 and 2023 in a level 1 trauma center. Two groups were compared: children with Glasgow Coma Scale (GCS) score ≤ 8 and children with GCS > 8. We calculated the predictive values to define the accuracy of blood glucose as a biomarker of brain injury.

RESULTS

Ninety-two medical records were included for analysis. Hyperglycemia predominated in cases with GCS ≤ 8 (48% vs 3%; p < 0.0001; OR, 30; 95% CI, 5.9902-150.2448). The glycemic measurement considering the cutoff point of 200 mg/dL or 11.1 mmol/L showed a specificity of 97%, a positive predictive value of 86%, an accuracy of 84%, and a likelihood ratio for a positive test of 16.

CONCLUSION

Victims with GCS ≤ 8 are 16 times more likely to develop acute hyperglycemia after TBI when compared to those with GCS > 8. Blood glucose is a biomarker with an accuracy of 84% to predict severe brain injury, considering the cutoff point of 200 mg/dL or 11.1 mmol/L.

Biofluid, Imaging, Physiological, and Functional Biomarkers of Mild Traumatic Brain Injury and Subconcussive Head Impacts

Post-concussive symptoms are frequently reported by individuals who sustain mild traumatic brain injuries (mTBIs) and subconcussive head impacts, even when evidence of intracranial pathology is lacking. Current strategies used to evaluate head injuries, which primarily rely on self-report, have a limited ability to predict the incidence, severity, and duration of post-concussive symptoms that will develop in an individual patient. In addition, these self-report measures have little association with the underlying mechanisms of pathology that may contribute to persisting symptoms, impeding advancement in precision treatment for TBI. Emerging evidence suggests that biofluid, imaging, physiological, and functional biomarkers associated with mTBI and subconcussive head impacts may address these shortcomings by providing more objective measures of injury severity and underlying pathology. Interest in the use of biomarker data has rapidly accelerated, which is reflected by the recent efforts of organizations such as the National Institute of Neurological Disorders and Stroke and the National Academies of Sciences, Engineering, and Medicine to prioritize the collection of biomarker data during TBI characterization in acute-care settings. Thus, this review aims to describe recent progress in the identification and development of biomarkers of mTBI and subconcussive head impacts and to discuss important considerations for the implementation of these biomarkers in clinical practice.

Advances in development of biomarkers for brain damage and ischemia

Acquired brain injury is an urgent situation that requires rapid diagnosis and treatment. Magnetic resonance imaging (MRI) and computed tomography (CT) are required for accurate diagnosis. However, these methods are costly and require substantial infrastructure and specialized staff. Circulatory biomarkers of acute brain injury may help in the management of patients with acute cerebrovascular events and prevent poor outcome and mortality. The purpose of this review is to provide an overview of the development of potential biomarkers of brain damage to increase diagnostic possibilities. For this purpose, we searched the PubMed database of studies on the diagnostic potential of brain injury biomarkers. We also accessed information from Clinicaltrials.gov to identify any clinical trials of biomarker measurements for the diagnosis of brain damage. In total, we present 41 proteins, enzymes and hormones that have been considered as biomarkers for brain injury, of which 20 have been studied in clinical trials. Several microRNAs have also emerged as potential clinical biomarkers for early diagnosis. Combining multiple biomarkers in a panel, along with other parameters, is yielding promising outcomes.

A systematic review and meta-analysis of major blood protein biomarkers that predict unfavorable outcomes in severe traumatic brain injury

INTRODUCTION

Severe traumatic brain injury (TBI) presentation and late clinical outcomes are usually evaluated by the Glasgow Outcome Scale-Extended (GOS-E), which lacks strong prognostic predictability. Several blood biomarkers have been linked to TBI, such as Tau, GFAP, UCH-L1, S-100B, and NSE. Clinical values of TBI biomarkers have yet to be evaluated in a focused multi-study meta-analysis. We reviewed relevant articles evaluating potential relationships between TBI biomarkers and both early and 6-month outcomes.

METHODS

All PubMed article publications from January 2000 to November 2023 with the search criteria "Protein Biomarker" AND "Traumatic Brain Injury" were included. Amongst all comparative studies, the sensitivity means and range values of biomarkers in predicting CT Rotterdam scores, ICU admission in the early period, or predicting GOS-E < 4 at the 6-month period were calculated from confusion matrices. Sensitivity values were modeled for each biomarker across studies and compared statistically for heterogeneity and differences.

RESULTS

From the 65 articles that met the criteria, 13 were included in this study. Six articles involved early-period TBI outcomes and seven involved 6-month outcomes. In the early period TBI outcomes, GFAP had a superior sensitivity to UCH-L1 and S-100B, and similar sensitivity to the CT Rotterdam score. In the 6-month period TBI outcomes, total Tau and NSE both had significant interstudy heterogeneity, making them inferior to GFAP, phosphorylated Tau, UCH-L1, and S-100B, all four of which had similar sensitivities at 75 %. This sensitivity range at 6-month outcomes was still relatively inferior to the CT Rotterdam score. Total Tau did not show any prognostic advantage at six months with GOS-E < 4, and phosphorylated Tau was similar in its sensitivity to other biomarkers such as GFAP and UCH-L1 and still inferior to the CT Rotterdam score.

CONCLUSION

This data suggests that TBI protein biomarkers do not possess better prognostic value with regards to outcomes.

Sphingolipid changes in mouse brain and plasma after mild traumatic brain injury at the acute phases

BACKGROUND

Traumatic brain injury (TBI) causes neuroinflammation and can lead to long-term neurological dysfunction, even in cases of mild TBI (mTBI). Despite the substantial burden of this disease, the management of TBI is precluded by an incomplete understanding of its cellular mechanisms. Sphingolipids (SPL) and their metabolites have emerged as key orchestrators of biological processes related to tissue injury, neuroinflammation, and inflammation resolution. No study so far has investigated comprehensive sphingolipid profile changes immediately following TBI in animal models or human cases. In this study, sphingolipid metabolite composition was examined during the acute phases in brain tissue and plasma of mice following mTBI.

METHODS

Wildtype mice were exposed to air-blast-mediated mTBI, with blast exposure set at 50-psi on the left cranium and 0-psi designated as Sham. Sphingolipid profile was analyzed in brain tissue and plasma during the acute phases of 1, 3, and 7 days post-TBI via liquid-chromatography-mass spectrometry. Simultaneously, gene expression of sphingolipid metabolic markers within brain tissue was analyzed using quantitative reverse transcription-polymerase chain reaction. Significance (P-values) was determined by non-parametric t-test (Mann-Whitney test) and by Tukey's correction for multiple comparisons.

RESULTS

In post-TBI brain tissue, there was a significant elevation of 1) acid sphingomyelinase (aSMase) at 1- and 3-days, 2) neutral sphingomyelinase (nSMase) at 7-days, 3) ceramide-1-phosphate levels at 1 day, and 4) monohexosylceramide (MHC) and sphingosine at 7-days. Among individual species, the study found an increase in C18:0 and a decrease in C24:1 ceramides (Cer) at 1 day; an increase in C20:0 MHC at 3 days; decrease in MHC C18:0 and increase in MHC C24:1, sphingomyelins (SM) C18:0, and C24:0 at 7 days. Moreover, many sphingolipid metabolic genes were elevated at 1 day, followed by a reduction at 3 days and an absence at 7-days post-TBI. In post-TBI plasma, there was 1) a significant reduction in Cer and MHC C22:0, and an increase in MHC C16:0 at 1 day; 2) a very significant increase in long-chain Cer C24:1 accompanied by significant decreases in Cer C24:0 and C22:0 in MHC and SM at 3 days; and 3) a significant increase of C22:0 in all classes of SPL (Cer, MHC and SM) as well as a decrease in Cer C24:1, MHC C24:1 and MHC C24:0 at 7 days.

CONCLUSIONS

Alterations in sphingolipid metabolite composition, particularly sphingomyelinases and short-chain ceramides, may contribute to the induction and regulation of neuroinflammatory events in the early stages of TBI, suggesting potential targets for novel diagnostic, prognostic, and therapeutic strategies in the future.

Management of Pediatric Mild Traumatic Brain Injury Patients: S100b, Glial Fibrillary Acidic Protein, and Heart Fatty-Acid-Binding Protein Promising Biomarkers

Children are highly vulnerable to mild traumatic brain injury (mTBI). Blood biomarkers can help in their management. This study evaluated the performances of biomarkers, in discriminating between children with mTBI who had intracranial injuries (ICIs) on computed tomography (CT+) and (1) patients without ICI (CT-) or (2) both CT- and in-hospital-observation without CT patients. The aim was to rule out the need of unnecessary CT scans and decrease the length of stay in observation in the emergency department (ED). Newborns to teenagers (≤16 years old) with mTBI (Glasgow Coma Scale > 13) were included. S100b, glial fibrillary acidic protein (GFAP), and heart fatty-acid-binding protein (HFABP) performances to identify patients without ICI were evaluated through receiver operating characteristic curves, where sensitivity was set at 100%. A total of 222 mTBI children sampled within 6 h since their trauma were reported. Nineteen percent (n = 43/222) underwent CT scan examination, whereas the others (n = 179/222) were kept in observation at the ED. Sixteen percent (n = 7/43) of the children who underwent a CT scan had ICI, corresponding to 3% of all mTBI-included patients. When sensibility (SE) was set at 100% to exclude all patients with ICI, GFAP yielded 39% specificity (SP), HFABP 37%, and S100b 34% to rule out the need of CT scans. These biomarkers were even more performant: 52% SP for GFAP, 41% for HFABP, and 39% for S100b, when discriminating CT+ versus both in-hospital-observation and CT- patients. These markers can significantly help in the management of patients in the ED, avoiding unnecessary CT scans, and reducing length of stay for children and their families.

Ameliorative properties of quercetin in the treatment of traumatic brain injury: a mechanistic review based on underlying mechanisms

Traumatic brain injury (TBI) is a leading cause of disability worldwide, with an estimated annual incidence of 27-69 million. TBI is a severe condition that can lead to high mortality rates and long-term cognitive, behavioral, and physical impairments in young adults. It is a significant public health concern due to the lack of effective treatments available. Quercetin, a natural flavonoid found in various fruits and vegetables, has demonstrated therapeutic potential with anti-inflammatory, antioxidant, and neuroprotective properties. Recently, some evidence has accentuated the ameliorating effects of quercetin on TBI. This review discusses quercetin's ability to reduce TBI-related damage by regulating many cellular and molecular pathways. Quercetin in vitro and in vivo studies exhibit promise in reducing inflammation, oxidative stress, apoptosis, and enhancing cognitive function post-TBI. Further clinical investigation into quercetin's therapeutic potential as a readily available adjuvant in the treatment of TBI is warranted in light of these findings. This review adds to our knowledge of quercetin's potential in treating TBI by clarifying its mechanisms of action.

A Narrative Review of Existing and Developing Biomarkers in Acute Traumatic Brain Injury for Potential Military Deployed Use

INTRODUCTION

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality in both adult civilian and military populations. Currently, diagnostic and prognostic methods are limited to imaging and clinical findings. Biomarker measurements offer a potential method to assess head injuries and help predict outcomes, which has a potential benefit to the military, particularly in the deployed setting where imaging modalities are limited. We determine how biomarkers such as ubiquitin C-terminal hydrolase-L1 (UCH-L1), glial fibrillary acidic protein (GFAP), S100B, neurofilament light chain (NFL), and tau proteins can offer important information to guide the diagnosis, acute management, and prognosis of TBI, specifically in military personnel.

MATERIALS AND METHODS

We performed a narrative review of peer-reviewed literature using online databases of Google Scholar and PubMed. We included articles published between 1988 and 2022.

RESULTS

We screened a total of 73 sources finding a total of 39 original research studies that met inclusion for this review. We found five studies that focused on GFAP, four studies that focused on UCH-L1, eight studies that focused on tau proteins, six studies that focused on NFL, and eight studies that focused on S100B. The remainder of the studies included more than one of the biomarkers of interest.

CONCLUSIONS

TBI occurs frequently in the military and civilian settings with limited methods to diagnose and prognosticate outcomes. We highlighted several promising biomarkers for these purposes including S100B, UCH-L1, NFL, GFAP, and tau proteins. S100B and UCH-L1 appear to have the strongest data to date, but further research is necessary. The robust data that explain the optimal timing and, more importantly, trending of these biomarker measurements are necessary before widespread application.

Preventable trauma deaths in the Western Cape of South Africa: A consensus-based panel review

Injury causes 4.4 million deaths worldwide annually. 90% of all injury-related deaths occur in low-and-middle income countries. Findings from expert-led trauma death reviews can inform strategies to reduce trauma deaths. A cohort of trauma decedents was identified from an on-going study in the Western Cape Province of South Africa. For each case, demographics, injury characteristics, time and location of death and postmortem findings were collected. An expert multidisciplinary panel of reviewed each case, determined preventability and made recommendations for improvement. Analysis of preventable and non-preventable cases was performed using Chi-square, Fisher's exact, and Wilcoxon signed rank tests. A rapid qualitative analysis of recommendations was conducted and descriptively summarized. 138 deaths (48 deceased-on-scene and 90 pre- or in-hospital deaths) were presented to 23 panelists. Overall, 46 (33%) of deaths reviewed were considered preventable or potentially preventable. Of all pre- and in-hospital deaths, late deaths (>24 hours) were more frequently preventable (22, 56%) and due to multi-organ failure and sepsis, compared to early deaths (≤24 hours) with 32 (63%) that were non-preventable and due to central nervous system injury and haemorrhage. 45% of pre and in-hospital deaths were preventable or potentially preventable. The expert panel recommended strengthening community based primary prevention strategies for reducing interpersonal violence alongside health system improvements to facilitate high quality care. For the health system the panel's key recommendations included improving team-based care, adherence to trauma protocols, timely access to radiology, trauma specialists, operative and critical care.

The role of the physiotherapist in concussion

In the last decade, concussion research has exploded in multiple fields of scientific research. This has helped to clarify what causes, influences, and perpetuates human concussion, and displays the integral role physiotherapists play in concussion management. In this article we discuss the latest research relevant to the key role of physiotherapy in concussion management. A narrative review of the literature on concussion was conducted. The current review analyses how concussion has influenced physiotherapy in several categories: assessment, treatment, management, research rigour and building the profile of the profession. Scientific concussion research has largely converged in support of the role of physiotherapists utilising specific components including: (1) autonomic, (2) cervicogenic, (3) vestibulo-ocular and (4) psychological approaches to management. Latest research supports the critical role of physiotherapy in concussion care in the assessment, management, and prevention of concussion with scope for further interdisciplinary collaborations.

Clinical implications

Concussion is complex. A basic mental health, Vestibular Ocular Motor Screening (VOMS) and four key components relating to concussion management (autonomic, cervicogenic, vestibular oculomotor, and psychological approaches to management) should be included in the undergraduate and postgraduate curriculum. This will aid clinical physiotherapists to support their patients. A call to advance more intradisciplinary physiotherapy teamwork should be encouraged as valuable knowledge sharing is potentially lost within the framework of 'specialisation'. If needed, the skills of a greater interdisciplinary team are imperative to facilitate patient management and recovery from this multi-faceted injury.

Breaking barriers in trauma research: A narrative review of opportunities to leverage veterinary trauma for accelerated translation to clinical solutions for pets and people

Trauma is a common cause of morbidity and mortality in humans and companion animals. Recent efforts in procedural development, training, quality systems, data collection, and research have positively impacted patient outcomes; however, significant unmet need still exists. Coordinated efforts by collaborative, translational, multidisciplinary teams to advance trauma care and improve outcomes have the potential to benefit both human and veterinary patient populations. Strategic use of veterinary clinical trials informed by expertise along the research spectrum (i.e., benchtop discovery, applied science and engineering, large laboratory animal models, clinical veterinary studies, and human randomized trials) can lead to increased therapeutic options for animals while accelerating and enhancing translation by providing early data to reduce the cost and the risk of failed human clinical trials. Active topics of collaboration across the translational continuum include advancements in resuscitation (including austere environments), acute traumatic coagulopathy, trauma-induced coagulopathy, traumatic brain injury, systems biology, and trauma immunology. Mechanisms to improve funding and support innovative team science approaches to current problems in trauma care can accelerate needed, sustainable, and impactful progress in the field. This review article summarizes our current understanding of veterinary and human trauma, thereby identifying knowledge gaps and opportunities for collaborative, translational research to improve multispecies outcomes. This translational trauma group of MDs, PhDs, and DVMs posit that a common understanding of injury patterns and resulting cellular dysregulation in humans and companion animals has the potential to accelerate translation of research findings into clinical solutions.

Mortality Predictors for Adult Patients with Mild-to-Moderate Traumatic Brain Injury: A Literature Review

Traumatic brain injuries (TBIs) represent a significant public health concern, with mild-to-moderate cases comprising a substantial portion of incidents. Understanding the predictors of mortality among adult patients with mild-to-moderate TBIs is crucial for optimizing clinical management and improving outcomes. This literature review examines the existing research to identify and analyze the mortality predictors in this patient population. Through a comprehensive review of peer-reviewed articles and clinical studies, key prognostic factors, such as age, Glasgow Coma Scale (GCS) score, the presence of intracranial hemorrhage, pupillary reactivity, and coexisting medical conditions, are explored. Additionally, this review investigates the role of advanced imaging modalities, biomarkers, and scoring systems in predicting mortality following a mild-to-moderate TBI. By synthesizing the findings from diverse studies, this review aims to provide clinicians and researchers with valuable insights into the factors influencing mortality outcomes in adult patients with a mild-to-moderate TBI, thus facilitating more informed decision making and targeted interventions in clinical practice.

Salivary and Serum Interleukin-6: A Credible Marker for Predicting Oral Leukoplakia and Oral Squamous Cell Carcinoma by Enzyme-Linked Immunosorbent Assay (ELISA)

BACKGROUND

Oral squamous cell carcinoma (OSCC) is the most prevalent subtype of oral cancer. Detecting oral potentially malignant disorders (OPMDs) in their early stages is crucial to prevent their advancement into OSCC. One of the primary factors contributing to OSCC is tobacco use, which can lead to increased production of cytokines. Among these cytokines, interleukin-6 (IL-6), an immune molecule involved in inflammation, may serve as a valuable indicator for assessing the progression of OPMDs and OSCCs.

AIMS

The aim of this study is to assess the levels of IL6 in both serum and saliva using the enzyme-linked immunosorbent assay (ELISA) technique and to determine the prognostic value of these measurements in individuals with oral leukoplakia and OSCC.

MATERIALS AND METHODS

The research involved 45 participants, who were categorized into three groups: OSCC (15), leukoplakia (15), and a control group consisting of healthy individuals (15). Saliva and serum samples were collected from each individual within all three groups and analyzed using the ELISA method. Subsequently, the gathered data underwent statistical analysis for evaluation.

RESULTS

There were elevated levels of IL-6 in both saliva and serum among individuals with OSCC in comparison to those with leukoplakia and the healthy control group, and this difference was statistically significant. The analysis of ROC (Receiver Operating Characteristic) curves demonstrated that salivary IL-6 was a more effective indicator than serum IL-6 for detecting the advancement of OSCC. As the histological grade of differentiation increased in both OSCC and leukoplakia cases, there was a corresponding rise in salivary IL-6 levels.

CONCLUSION

Both salivary and serum IL-6 levels have the potential to serve as valuable prognostic biomarkers for oral leukoplakia and OSCC which shows possible involvement of IL-6 in the development and progression of these conditions. Salivary IL-6 is a superior prognostic marker compared to serum IL-6 due to its non-invasive nature which makes it a useful tool for mass screening.

Management of Head Trauma

Traumatic brain injury (TBI) represents a heterogenous spectrum of disease. It is essential to rapidly assess a patient's neurologic status and implement measures to prevent secondary brain injury. Intracranial hypertension, a common sequela of TBI, is managed in a tiered and systematic fashion, starting with the least invasive and moving toward the most invasive. TBI has long-lasting effects on patients and their families and represents a substantial financial and social influence on society. Research regarding the prognosis and treatment of TBI is essential to limit the influence of this widespread disease.

A Novel Experimental Approach for the Measurement of Vibration-Induced Changes in the Rheological Properties of Ex Vivo Ovine Brain Tissue

Increased incidence of traumatic brain injury (TBI) imposes a growing need to understand the pathology of brain trauma. A correlation between the incidence of multiple brain traumas and rates of behavioural and cognitive deficiencies has been identified amongst people that experienced multiple TBI events. Mechanically, repetitive TBIs may affect brain tissue in a similar way to cyclic loading. Hence, the potential susceptibility of brain tissue to mechanical fatigue is of interest. Although temporal changes in ovine brain tissue viscoelasticity and biological fatigue of other tissues such as tendons and arteries have been investigated, no methodology currently exists to cyclically load ex vivo brain tissue. A novel rheology-based approach found a consistent, initial stiffening response of the brain tissue before a notable softening when subjected to a subsequential cyclic rotational shear. History dependence of the mechanical properties of brain tissue indicates susceptibility to mechanical fatigue. Results from this investigation increase understanding of the fatigue properties of brain tissue and could be used to strengthen therapy and prevention of TBI, or computational models of repetitive head injuries.

Recent Research Trends in Neuroinflammatory and Neurodegenerative Disorders

Neuroinflammatory and neurodegenerative disorders including Alzheimer's disease (AD), Parkinson's disease (PD), traumatic brain injury (TBI) and Amyotrophic lateral sclerosis (ALS) are chronic major health disorders. The exact mechanism of the neuroimmune dysfunctions of these disease pathogeneses is currently not clearly understood. These disorders show dysregulated neuroimmune and inflammatory responses, including activation of neurons, glial cells, and neurovascular unit damage associated with excessive release of proinflammatory cytokines, chemokines, neurotoxic mediators, and infiltration of peripheral immune cells into the brain, as well as entry of inflammatory mediators through damaged neurovascular endothelial cells, blood-brain barrier and tight junction proteins. Activation of glial cells and immune cells leads to the release of many inflammatory and neurotoxic molecules that cause neuroinflammation and neurodegeneration. Gulf War Illness (GWI) and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) are chronic disorders that are also associated with neuroimmune dysfunctions. Currently, there are no effective disease-modifying therapeutic options available for these diseases. Human induced pluripotent stem cell (iPSC)-derived neurons, astrocytes, microglia, endothelial cells and pericytes are currently used for many disease models for drug discovery. This review highlights certain recent trends in neuroinflammatory responses and iPSC-derived brain cell applications in neuroinflammatory disorders.

Appropriate incorporation of susceptibility-weighted magnetic resonance imaging into routine imaging protocols for accurate diagnosis of traumatic brain injuries: a systematic review

Traumatic brain injury (TBI) results from physical or traumatic injuries to the brain's surrounding bony structures and associated tissues, which can lead to various sequelae, including simple concussion, acute epidural hematoma, parenchymal contusions, subarachnoid hemorrhage, diffuse axonal injury, and chronic traumatic encephalopathy. Susceptibility-weighted imaging (SWI) has enhanced the accuracy of neuroimaging for these injuries. SWI is based on 3D gradient echo magnetic resonance imaging (MRI) with long echo times and flow compensation. Owing to its sensitivity to deoxyhemoglobin, hemosiderin, iron, and calcium, SWI is extremely informative and superior to conventional MRI for the diagnosis and follow-up of patients with acute, subacute, and prolonged hemorrhage. This systematic review aimed to evaluate and summarize the published articles that report SWI results for the evaluation of TBI and to determine correlations between clinical status and SWI results. Consequently, our analysis also aimed to identify the appropriate MRI sequences to use in the assessment of patients with TBI. We searched the Medline and Embase online electronic databases for relevant papers published from 2012 onwards. We found that SWI had higher sensitivity than gradient echo MRI in detecting and characterizing microbleeds in TBIs and was able to differentiate diamagnetic calcifications from paramagnetic microhemorrhages. However, it is important that future research not only continues to evaluate the utility of SWI in TBIs but also attempts to overcome the limitations of the studies described in this review, which should help validate the conclusions and recommendations from our analysis.

Biofluid-based Biomarkers in Traumatic Brain Injury: A Narrative Review

Traumatic brain injury (TBI) is a complex condition characterized by a multifaceted pathophysiology. It presents significant diagnostic and prognostic challenges in clinical settings. This narrative review explores the evolving role of biofluid biomarkers as essential tools in the diagnosis, prognosis, and treatment of TBI. In recent times, preclinical and clinical trials utilizing these biofluid biomarkers have been actively pursued internationally. Among the biomarkers for nerve tissue proteins are neuronal biomarkers like neuronal specific enolase and ubiquitin C-terminal hydrolase L1; astroglia injury biomarkers such as S100B and glial fibrillary acidic protein; axonal injury and demyelination biomarkers, including neurofilaments and myelin basic protein; new axonal injury and neurodegeneration biomarkers like total tau and phosphorylated tau; and others such as spectrin breakdown products and microtubule-associated protein 2. The interpretation of these biomarkers can be influenced by various factors, including secretion from organs other than the injury site and systemic conditions. This review highlights the potential of these biomarkers to transform TBI management and emphasizes the need for continued research to validate their efficacy, refine testing platforms, and ultimately improve patient care and outcomes.

The Prognostic Role of Candidate Serum Biomarkers in the Post-Acute and Chronic Phases of Disorder of Consciousness: A Preliminary Study

INTRODUCTION

Serum biomarkers, such as Neurofilament Light (NF-L), Glial Fibrillary Acidic Protein (GFAP), Ubiquitin C-terminal Hydrolase (UCH-L1), and Total-tau (T-Tau) have been proposed for outcome prediction in the acute phase of severe traumatic brain injury, but they have been less investigated in patients with prolonged DoC (p-DoC).

METHODS

We enrolled 25 p-DoC patients according to the Coma Recovery Scale-Revised (CRS-R). We identified different time points: injury onset (t0), first blood sampling at admission in Neurorehabilitation (t1), and second blood sampling at discharge (t2). Patients were split into improved (improved level of consciousness from t1 to t2) and not-improved (unchanged or worsened level of consciousness from t1 to t2).

RESULTS

All biomarker levels decreased over time, even though each biomarker reveals typical features. Serum GFAP showed a weak correlation between t1 and t2 (p = 0.001), while no correlation was observed for serum NF-L (p = 0.955), UCH-L1 (p = 0.693), and T-Tau (p = 0.535) between t1 and t2. Improved patients showed a significant decrease in the level of NF-L (p = 0.0001), UCH-L1 (p = 0.001), and T-Tau (p = 0.002), but not for serum GFAP (p = 0.283). No significant statistical differences were observed in the not-improved group.

CONCLUSIONS

A significant correlation was found between the level of consciousness improvement and decreased NF-L, UCH-L1, and T-Tau levels. Future studies on the association of serum biomarkers with neurophysiological and neuroimaging prognostic indicators are recommended.

Successful harmonization in EpiBioS4Rx biomarker study on post-traumatic epilepsy paves the way towards powered preclinical multicenter studies

OBJECTIVE

Project 1 of the Preclinical Multicenter Epilepsy Bioinformatics Study for Antiepileptogenic Therapy (EpiBioS4Rx) consortium aims to identify preclinical biomarkers for antiepileptogenic therapies following traumatic brain injury (TBI). The international participating centers in Finland, Australia, and the United States have made a concerted effort to ensure protocol harmonization. Here, we evaluate the success of harmonization process by assessing the timing, coverage, and performance between the study sites.

METHOD

We collected data on animal housing conditions, lateral fluid-percussion injury model production, postoperative care, mortality, post-TBI physiological monitoring, timing of blood sampling and quality, MR imaging timing and protocols, and duration of video-electroencephalography (EEG) follow-up using common data elements. Learning effect in harmonization was assessed by comparing procedural accuracy between the early and late stages of the project.

RESULTS

The animal housing conditions were comparable between the study sites but the postoperative care procedures varied. Impact pressure, duration of apnea, righting reflex, and acute mortality differed between the study sites (p < 0.001). The severity of TBI on D2 post TBI assessed using the composite neuroscore test was similar between the sites, but recovery of acute somato-motor deficits varied (p < 0.001). A total of 99% of rats included in the final cohort in UEF, 100% in Monash, and 79% in UCLA had blood samples taken at all time points. The timing of sampling differed on day (D)2 (p < 0.05) but not D9 (p > 0.05). Plasma quality was poor in 4% of the samples in UEF, 1% in Monash and 14% in UCLA. More than 97% of the final cohort were MR imaged at all timepoints in all study sites. The timing of imaging did not differ on D2 and D9 (p > 0.05), but varied at D30, 5 months, and ex vivo timepoints (p < 0.001). The percentage of rats that completed the monthly high-density video-EEG follow-up and the duration of video-EEG recording on the 7th post-injury month used for seizure detection for diagnosis of post-traumatic epilepsy differed between the sites (p < 0.001), yet the prevalence of PTE (UEF 21%, Monash 22%, UCLA 23%) was comparable between the sites (p > 0.05). A decrease in acute mortality and increase in plasma quality across time reflected a learning effect in the TBI production and blood sampling protocols.

SIGNIFICANCE

Our study is the first demonstration of the feasibility of protocol harmonization for performing powered preclinical multi-center trials for biomarker and therapy discovery of post-traumatic epilepsy.

GFAP and UCHL1 in Non-traumatic SAH: The Story thus Far. A Systematic Review of the Literature

OBJECTIVE

Non-traumatic subarachnoid hemorrhage (SAH) is associated with a high percentage of misdiagnosis and poor prognosis. Biomarkers could be useful in the identification, treatment/management guidance, and outcome improvement of SAH patients. The current systematic review aims to investigate the potential role of biomarkers GFAP (Glial Fibrillary Acidic Protein) and UCH-L1 (Ubiquitin C-Terminal Hydrolase L1) in the diagnosis and prognosis of non-traumatic SAH.

METHODS

A systematic search of PubMed, Scopus, and Web of Science databases was conducted from their inception through February 2023.

RESULTS

17 studies met the inclusion criteria and were included in this review. The vast majority of the included studies (82%) were on GFAP. Most studies used blood and/or CSF samples and incorporated multiple measurements through the initial hospitalization days. The majority of identified studies reported significantly higher levels of GFAP and UCHL1 in SAH patients with poor outcomes. There was notable variation in the specimen type and the timing of sampling.

CONCLUSION

Quantification of GFAP and UCHL1 through the initial days of hospitalization shows promise in the prediction of SAH patient outcomes. Further research is nevertheless warranted to confirm these findings and further clarify the use of the two biomarkers in SAH diagnosis and the prediction of severity and secondary events.

Blood biomarkers for traumatic brain injury: A narrative review of current evidence

Introduction

A blood-based biomarker (BBBM) test could help to better stratify patients with traumatic brain injury (TBI), reduce unnecessary imaging, to detect and treat secondary insults, predict outcomes, and monitor treatment effects and quality of care.

Research question

What evidence is available for clinical applications of BBBMs in TBI and how to advance this field?

Material and methods

This narrative review discusses the potential clinical applications of core BBBMs in TBI. A literature search in PubMed, Scopus, and ISI Web of Knowledge focused on articles in English with the words "traumatic brain injury" together with the words "blood biomarkers", "diagnostics", "outcome prediction", "extracranial injury" and "assay method" alone-, or in combination.

Results

Glial fibrillary acidic protein (GFAP) combined with Ubiquitin C-terminal hydrolase-L1(UCH-L1) has received FDA clearance to aid computed tomography (CT)-detection of brain lesions in mild (m) TBI. Application of S100B led to reduction of head CT scans. GFAP may also predict magnetic resonance imaging (MRI) abnormalities in CT-negative cases of TBI. Further, UCH-L1, S100B, Neurofilament light (NF-L), and total tau showed value for predicting mortality or unfavourable outcome. Nevertheless, biomarkers have less role in outcome prediction in mTBI. S100B could serve as a tool in the multimodality monitoring of patients in the neurointensive care unit.

Discussion and conclusion

Largescale systematic studies are required to explore the kinetics of BBBMs and their use in multiple clinical groups. Assay development/cross validation should advance the generalizability of those results which implicated GFAP, S100B and NF-L as most promising biomarkers in the diagnostics of TBI.

The relationship between hemoglobin/red blood cell distribution width ratio and mortality in patients with intracranial hemorrhage: a possible protective effect for the elderly?

Intracranial hemorrhage (ICH) is a neurological emergency with a poor prognosis. This study aimed to understand the association between hemoglobin levels, red blood cell distribution width ratio (HRR), and mortality in patients with ICH. Information on patients with ICH was extracted from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Cox proportional risk models were used to assess the relationship between HRR and 28-day and 90-day mortality, and constructed by adjusting for relevant covariates. Segmented regression models and smoothing curves were used to analyze the linear relationship between HRR and mortality. This study recruited 4,716 patients with ICH. The HRR Q4 group was negatively associated with the 28- and 90-day mortality. For patients aged > 65 years, the right-hand threshold inflection points of the HRR were 0.92 and 0.93, respectively, which were negatively associated with 28-day mortality (HR:0.06, 95% CI 0.01, 0.35, p = 0.0016) and with 90-day mortality (p = 0.0006). In the non-linear model, both 28-day mortality (HR, 0.17; 95% CI 0.04-0.75, p = 0.0191; HRR > 0.89) and 90-day mortality (HR, 0.13; 95% CI 0.04-0.49, p = 0.0022; HRR > 0.85) were associated in men. In the subgroup analysis, the negative association between HRR and mortality was more pronounced in patients > 65 years of age, as well as in patients with non-dementia, diabetes, and malignant cancer. We found a non-linear relationship between mortality and the HRR in elderly patients, and a higher HRR was negatively associated with mortality in patients with ICH.

Prognostic Value of Serum Biomarkers in Patients With Moderate-Severe Traumatic Brain Injury, Differentiated by Marshall Computer Tomography Classification

Prognostication is challenging in patients with traumatic brain injury (TBI) in whom computed tomography (CT) fails to fully explain a low level of consciousness. Serum biomarkers reflect the extent of structural damage in a different way than CT does, but it is unclear whether biomarkers provide additional prognostic value across the range of CT abnormalities. This study aimed to determine the added predictive value of biomarkers, differentiated by imaging severity. This prognostic study used data from the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study (2014-2017). The analysis included patients aged ≥16 years with a moderate-severe TBI (Glasgow Coma Scale [GCS] <13) who had an acute CT and serum biomarkers obtained ≤24h of injury. Of six protein biomarkers (GFAP, NFL, NSE, S100B, Tau, UCH-L1), the most prognostic panel was selected using lasso regression. The performance of established prognostic models (CRASH and IMPACT) was assessed before and after the addition of the biomarker panel and compared between patients with different CT Marshall scores (Marshall score <3 vs. Marshall score ≥3). Outcome was assessed at six months post-injury using the extended Glasgow Outcome Scale (GOSE), and dichotomized into favorable and unfavorable (GOSE <5). We included 872 patients with moderate-severe TBI. The mean age was 47 years (range 16-95); 647 (74%) were male and 438 (50%) had a Marshall CT score <3. The serum biomarkers GFAP, NFL, S100B and UCH-L1 provided complementary prognostic information; NSE and Tau showed no added value. The addition of the biomarker panel to established prognostic models increased the area under the curve (AUC) by 0.08 and 0.03, and the explained variation in outcome by 13-14% and 7-8%, for patients with a Marshall score of <3 and ≥3, respectively. The incremental AUC of biomarkers for individual models was significantly greater when the Marshall score was <3 compared with ≥3 (p < 0.001). Serum biomarkers improve outcome prediction after moderate-severe TBI across the range of imaging severities and especially in patients with a Marshall score <3.

A systematic review of pediatric neuropsychological outcomes with proton versus photon radiation therapy: A call for equity in access to treatment

OBJECTIVE

There is increasing interest in the utilization of proton beam radiation therapy (PRT) to treat pediatric brain tumors based upon presumed advantages over traditional photon radiation therapy (XRT). PRT provides more conformal radiation to the tumor with reduced dose to healthy brain parenchyma. Less radiation exposure to brain tissue beyond the tumor is thought to reduce neuropsychological sequelae. This systematic review aimed to provide an overview of published studies comparing neuropsychological outcomes between PRT and XRT.

METHOD

PubMed, PsychINFO, Embase, Web of Science, Scopus, and Cochrane were systematically searched for peer-reviewed published studies that compared neuropsychological outcomes between PRT and XRT in pediatric brain tumor patients.

RESULTS

Eight studies were included. Six of the studies utilized retrospective neuropsychological data; the majority were longitudinal studies (n = 5). XRT was found to result in lower neuropsychological functioning across time. PRT was associated with generally stable neuropsychological functioning across time, with the exception of working memory and processing speed, which showed variable outcomes across studies. However, studies inconsistently included or considered medical and sociodemographic differences between treatment groups, which may have impacted neuropsychological outcomes.

CONCLUSIONS

Despite methodological limitations, including limited baseline neuropsychological evaluations, temporal variability between radiation treatment and first evaluation or initial and follow-up evaluations, and heterogenous samples, there is emerging evidence of sociodemographic inequities in access to PRT. With more institutions dedicating funding towards PRT, there may be the opportunity to objectively evaluate the neuropsychological benefits of patients matched on medical and sociodemographic variables.

Unraveling the Potential of EphA4: A Breakthrough Target and Beacon of Hope for Neurological Diseases

Erythropoietin-producing hepatocellular carcinoma A4 (EphA4) is a transmembrane receptor protein which is a part of the most prominent family of receptor tyrosine kinases (RTKs). It serves a crucial role in both physiological, biological, and functional states binding with their ligand like Ephrins. Its abundance in the majority of the body's systems has been reported. Moreover, it draws much attention in the CNS since it influences axonal and vascular guidance. Also, it has a widespread role at the pathological state of various CNS disorders. Reports suggest it obstructs axonal regeneration in various neurodegenerative diseases and neurological disorders. Although, neuro-regeneration is still an open challenge to the modern drug discovery community.  Hence, in this review, we will provide information about the role of EphA4 in neurological diseases by which it may emerge as a therapeutic target for CNS disease. We will also provide a glance at numerous signaling pathways that activate or inhibit the EphA4-associated biological processes contributing to the course of neurodegenerative diseases. Thus, this work might serve as a basis for futuristic studies that are related to the target-based drug discovery in the field of neuro-regeneration. Pathological and physiological events associated with EphA4 and Ephrin upregulation and interaction.

Levels of Arachidonic Acid-Derived Oxylipins and Anandamide Are Elevated Among Military APOE ɛ4 Carriers With a History of Mild Traumatic Brain Injury and Post-Traumatic Stress Disorder Symptoms

Currently approved blood biomarkers detect intracranial lesions in adult patients with mild to moderate traumatic brain injury (TBI) acutely post-injury. However, blood biomarkers are still needed to help with a differential diagnosis of mild TBI (mTBI) and post-traumatic stress disorder (PTSD) at chronic post-injury time points. Owing to the association between phospholipid (PL) dysfunction and chronic consequences of TBI, we hypothesized that examining bioactive PL metabolites (oxylipins and ethanolamides) would help identify long-term lipid changes associated with mTBI and PTSD. Lipid extracts of plasma from active-duty soldiers deployed to the Iraq/Afghanistan wars (control = 52, mTBI = 21, PTSD = 34, and TBI + PTSD = 13) were subjected to liquid chromatography/mass spectrometry analysis to examine oxylipins and ethanolamides. Linear regression analyses followed by post hoc comparisons were performed to assess the association of these lipids with diagnostic classifications. Significant differences were found in oxylipins derived from arachidonic acid (AA) between controls and mTBI, PTSD, and mTBI + PTSD groups. Levels of AA-derived oxylipins through the cytochrome P450 pathways and anandamide were significantly elevated among mTBI + PTSD patients who were carriers of the apolipoprotein E E4 allele. These studies demonstrate that AA-derived oxylipins and anandamide may be unique blood biomarkers of PTSD and mTBI + PTSD. Further, these AA metabolites may be indicative of an underlying inflammatory process that warrants further investigation. Future validation studies in larger cohorts are required to determine a potential application of this approach in providing a differential diagnosis of mTBI and PTSD in a clinical setting.

Post-mortem detection of neuronal and astroglial biochemical markers in serum and urine for diagnostics of traumatic brain injury

Currently available epidemiological data shows that traumatic brain injury (TBI) represents one of the leading causes of death that is associated with medico-legal practice, including forensic autopsy, criminological investigation, and neuropathological examination. Attention focused on TBI research is needed to advance its diagnostics in ante- and post-mortem cases with regard to identification and validation of novel biomarkers. Recently, several markers of neuronal, astroglial, and axonal injury have been explored in various biofluids to assess the clinical origin, progression, severity, and prognosis of TBI. Despite clinical usefulness, understanding their diagnostic accuracy could also potentially help translate them either into forensic or medico-legal practice, or both. The aim of this study was to evaluate post-mortem pro-BDNF, NSE, UCHL1, GFAP, S100B, SPTAN1, NFL, MAPT, and MBP levels in serum and urine in TBI cases. The study was performed using cases (n = 40) of fatal head injury and control cases (n = 20) of sudden death. Serum and urine were collected within ∼ 24 h after death and compared using ELISA test. In our study, we observed the elevated concentration levels of GFAP and MAPT in both serum and urine, elevated concentration levels of S100B and SPTAN1 in serum, and decreased concentration levels of pro-BDNF in serum compared to the control group. The obtained results anticipate the possible implementation of performed assays as an interesting tool for forensic and medico-legal investigations regarding TBI diagnosis where the head injury was not supposed to be the direct cause of death.

Single Versus Repetitive Traumatic Brain Injury: Current Knowledge on the Chronic Outcomes, Neuropathology and the Role of TDP-43 Proteinopathy

Traumatic brain injury (TBI) is one of the most important causes of death and disability in adults and thus an important public health problem. Following TBI, secondary pathophysiological processes develop over time and condition the development of different neurodegenerative entities. Previous studies suggest that neurobehavioral changes occurring after a single TBI are the basis for the development of Alzheimer's disease, while repetitive TBI is considered to be a contributing factor for chronic traumatic encephalopathy development. However, pathophysiological processes that determine the evolvement of a particular chronic entity are still unclear. Human post-mortem studies have found combinations of amyloid, tau, Lewi bodies, and TAR DNA-binding protein 43 (TDP-43) pathologies after both single and repetitive TBI. This review focuses on the pathological changes of TDP-43 after single and repetitive brain traumas. Numerous studies have shown that TDP-43 proteinopathy noticeably occurs after repetitive head trauma. A relatively small number of available preclinical research on single brain injury are not in complete agreement with the results from the human samples, which makes it difficult to draw specific conclusions. Also, as TBI is considered a heterogeneous type of injury, different experimental trauma models and injury intensities may cause differences in the cascade of secondary injury, which should be considered in future studies. Experimental and post-mortem studies of TDP-43 pathobiology should be carried out, preferably in the same laboratories, to determine its involvement in the development of neurodegenerative conditions after one and repetitive TBI, especially in the context of the development of new therapeutic options.

Traumatic Brain Injury in Cameroon: A Prospective Observational Study in a Level I Trauma Centre

Background and Objective: About 14 million people will likely suffer a traumatic brain injury (TBI) per year by 2050 in sub-Saharan Africa. Studying TBI characteristics and their relation to outcomes can identify initiatives to improve TBI prevention and care. The objective of this study was to define the features and outcomes of TBI patients seen over a 1-year period in a level-I trauma centre in Cameroon. Materials and Methods: Data on demographics, causes, clinical aspects, and discharge status were collected over a period of 12 months. The Glasgow Outcome Scale-Extended (GOSE) and the Quality-of-Life Questionnaire after Brain Injury (QoLIBRI) were used to evaluate outcomes six months after TBI. Comparisons between two categorical variables were done using Pearson's chi-square test. Results: A total of 160 TBI patients participated in the study. The age group 15-45 years was most represented (78%). Males were more affected (90%). A low educational level was seen in 122 (76%) cases. Road traffic incidents (RTI) (85%), assaults (7.5%), and falls (2.5%) were the main causes of TBI, with professional bike riders being frequently involved (27%). Only 15 patients were transported to the hospital by ambulance, and 14 of these were from a referring hospital. CT-imaging was performed in 78% of cases, and intracranial traumatic abnormalities were identified in 64% of cases. Financial constraints (93%) was the main reason for not performing a CT scan. Forty-six (33%) patients were discharged against medical advice (DAMA) due to financial constraints. Mortality was 14% (22/160) and high in patients with severe TBI (46%). DAMA had poor outcomes with QoLIBRI. Only four patients received post-injury physical therapy services. Conclusions: TBI in Cameroon mainly results from RTIs and commonly affects young adult males. Lack of pre-hospital care, financial constraints limiting both CT scanning and medical care, and a lack of acute physiotherapy services likely influenced care and outcomes adversely.

The Role of Novel Imaging and Biofluid Biomarkers in Traumatic Axonal Injury: An Updated Review

Traumatic brain injury (TBI) is a leading cause of disability worldwide. Traumatic axonal injury (TAI) is a subtype of TBI resulting from high-impact forces that cause shearing and/or stretching of the axonal fibers in white matter tracts. It is present in almost half of cases of severe TBI and frequently associated with poor functional outcomes. Axonal injury results from axonotomy due to mechanical forces and the activation of a biochemical cascade that induces the activation of proteases. It occurs at a cellular level; hence, conventional imaging modalities often fail to display TAI lesions. However, the advent of novel imaging modalities, such as functional magnetic resonance imaging and fiber tractography, has significantly improved the detection and characteristics of TAI. Furthermore, the significance of several fluid and structural biomarkers has also been researched, while the contribution of omics in the detection of novel biomarkers is currently under investigation. In the present review, we discuss the role of imaging modalities and potential biomarkers in diagnosing, classifying, and predicting the outcome in patients with TAI.

Cellular and Molecular Pathophysiology of Traumatic Brain Injury: What Have We Learned So Far?

Traumatic brain injury (TBI) is one of the leading causes of long-lasting morbidity and mortality worldwide, being a devastating condition related to the impairment of the nervous system after an external traumatic event resulting in transitory or permanent functional disability, with a significant burden to the healthcare system. Harmful events underlying TBI can be classified into two sequential stages, primary and secondary, which are both associated with breakdown of the tissue homeostasis due to impairment of the blood-brain barrier, osmotic imbalance, inflammatory processes, oxidative stress, excitotoxicity, and apoptotic cell death, ultimately resulting in a loss of tissue functionality. The present study provides an updated review concerning the roles of brain edema, inflammation, excitotoxicity, and oxidative stress on brain changes resulting from a TBI. The proper characterization of the phenomena resulting from TBI can contribute to the improvement of care, rehabilitation and quality of life of the affected people.

Plasma neurofilament light admission levels and development of axonal pathology in mild traumatic brain injury

BACKGROUND

It is known that blood levels of neurofilament light (NF-L) and diffusion-weighted magnetic resonance imaging (DW-MRI) are both associated with outcome of patients with mild traumatic brain injury (mTBI). Here, we sought to examine the association between admission levels of plasma NF-L and white matter (WM) integrity in post-acute stage DW-MRI in patients with mTBI.

METHODS

Ninety-three patients with mTBI (GCS ≥ 13), blood sample for NF-L within 24 h of admission, and DW-MRI ≥ 90 days post-injury (median = 229) were included. Mean fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were calculated from the skeletonized WM tracts of the whole brain. Outcome was assessed using the Extended Glasgow Outcome Scale (GOSE) at the time of imaging. Patients were divided into CT-positive and -negative, and complete (GOSE = 8) and incomplete recovery (GOSE < 8) groups.

RESULTS

The levels of NF-L and FA correlated negatively in the whole cohort (p = 0.002), in CT-positive patients (p = 0.016), and in those with incomplete recovery (p = 0.005). The same groups showed a positive correlation with mean MD, AD, and RD (p < 0.001-p = 0.011). In CT-negative patients or in patients with full recovery, significant correlations were not found.

CONCLUSION

In patients with mTBI, the significant correlation between NF-L levels at admission and diffusion tensor imaging (DTI) measurements of diffuse axonal injury (DAI) over more than 3 months suggests that the early levels of plasma NF-L may associate with the presence of DAI at a later phase of TBI.

Association of Serum Brain-Derived Tau With Clinical Outcome and Longitudinal Change in Patients With Severe Traumatic Brain Injury

Importance

Blood-based measurements of total tau (T-tau) are commonly used to examine neuronal injury in patients with traumatic brain injury (TBI), but current assays do not differentiate between brain-derived tau (BD-tau) and tau produced in peripheral tissues. A novel assay for BD-tau has recently been reported that selectively quantifies nonphosphorylated tau of central nervous system origin in blood samples.

Objectives

To examine the association of serum BD-tau with clinical outcomes in patients with severe TBI (sTBI) and its longitudinal changes over 1 year.

Design, Setting, and Participants

This prospective cohort study was conducted at the neurointensive unit at the Sahlgrenska University Hospital, Gothenburg, Sweden, between September 1, 2006, and July 1, 2015. The study included 39 patients with sTBI followed up for up to 1 year. Statistical analysis was performed between October and November 2021.

Exposures

Serum BD-tau, T-tau, phosphorylated tau231 (p-tau231), and neurofilament light chain (NfL) measured on days 0, 7, and 365 after injury.

Main Outcomes and Measures

Associations of serum biomarkers with clinical outcome and longitudinal change in sTBI. Severity of sTBI was evaluated using the Glasgow Coma Scale at hospital admission, while clinical outcome was assessed with the Glasgow Outcome Scale (GOS) at 1-year follow-up. Participants were classified as having a favorable outcome (GOS score, 4-5) or unfavorable outcome (GOS score, 1-3).

Results

Among the 39 patients (median age at admission, 36 years [IQR, 22-54 years]; 26 men [66.7%]) in the study on day 0, the mean (SD) serum BD-tau level was higher among patients with unfavorable outcomes vs those with favorable outcomes (191.4 [190.8] pg/mL vs 75.6 [60.3] pg/mL; mean difference, 115.9 pg/mL [95% CI, 25.7-206.1 pg/mL]), while the other markers had smaller between-group mean differences (serum T-tau, 60.3 pg/mL [95% CI, -22.0 to 142.7 pg/mL]; serum p-tau231, 8.3 pg/mL [95% CI, -6.4 to 23.0 pg/mL]; serum NfL, -5.4 pg/mL [95% CI, -99.0 to 88.3 pg/mL]). Similar results were recorded on day 7. Longitudinally, baseline serum BD-tau concentrations showed slower decreases in the whole cohort (42.2% on day 7 [from 138.6 to 80.1 pg/mL] and 93.0% on day 365 [from 138.6 to 9.7 pg/mL]) compared with serum T-tau (81.5% on day 7 [from 57.3 to 10.6 pg/mL] and 99.0% on day 365 [from 57.3 to 0.6 pg/mL]) and p-tau231 (92.5% on day 7 [from 20.1 to 1.5 pg/mL] and 95.0% on day 365 [from 20.1 to 1.0 pg/mL]). These results did not change when considering clinical outcome, where T-tau decreased twice as fast as BD-tau in both groups. Similar results were obtained for p-tau231. Furthermore, the biomarker levels on day 365 were lower, compared with day 7, for BD-tau but not T-tau or p-tau231. Serum NfL had a different trajectory to the tau biomarkers, with levels increasing by 255.9% on day 7 compared with day 0 (from 86.8 to 308.9 pg/mL) but decreasing by 97.0% by day 365 vs day 7 (from 308.9 to 9.2 pg/mL).

Conclusions and Relevance

This study suggests that serum BD-tau, T-tau, and p-tau231 have differential associations with clinical outcome and 1-year longitudinal change in patients with sTBI. Serum BD-tau demonstrated utility as a biomarker to monitor outcomes in sTBI and can provide valuable information regarding acute neuronal damage.

Individualised profiling of white matter organisation in moderate-to-severe traumatic brain injury patients

BACKGROUND AND PURPOSE

Approximately 65% of moderate-to-severe traumatic brain injury (m-sTBI) patients present with poor long-term behavioural outcomes, which can significantly impair activities of daily living. Numerous diffusion-weighted MRI studies have linked these poor outcomes to decreased white matter integrity of several commissural tracts, association fibres and projection fibres in the brain. However, most studies have focused on group-based analyses, which are unable to deal with the substantial between-patient heterogeneity in m-sTBI. As a result, there is increasing interest and need in conducting individualised neuroimaging analyses.

MATERIALS AND METHODS

Here, we generated a detailed subject-specific characterisation of microstructural organisation of white matter tracts in 5 chronic patients with m-sTBI (29 - 49y, 2 females), presented as a proof-of-concept. We developed an imaging analysis framework using fixel-based analysis and TractLearn to determine whether the values of fibre density of white matter tracts at the individual patient level deviate from the healthy control group (n = 12, 8F, M_age = 35.7y, age range 25 - 64y).

RESULTS

Our individualised analysis revealed unique white matter profiles, confirming the heterogenous nature of m-sTBI and the need of individualised profiles to properly characterise the extent of injury. Future studies incorporating clinical data, as well as utilising larger reference samples and examining the test-retest reliability of the fixel-wise metrics are warranted.

CONCLUSIONS

Individualised profiles may assist clinicians in tracking recovery and planning personalised training programs for chronic m-sTBI patients, which is necessary to achieve optimal behavioural outcomes and improved quality of life.

Review on the Role of Salivary Biomarkers in the Diagnosis of Mild Traumatic Brain Injury and Post-Concussion Syndrome

(1) Background: While mild traumatic brain injuries (TBIs) are a major public health issue, post-concussion syndrome (PCS) remains a controversial entity. In both cases, the clinical diagnosis is mainly based on the symptoms and brain imaging evaluation. The current molecular biomarkers were described from blood and cerebrospinal fluid (CSF), yet both fluid collection methods are invasive. Saliva could be preferred in molecular diagnosis due to its non-invasive and non-expensive methods of acquisition, transport, and samples processing. (2) Objectives: In the present study, we aimed to review the latest developments in salivary biomarkers and their potential role in diagnosing mild TBIs, and PCS. (3) Results: In TBIs and PCS, a few novel studies focusing on salivary biomarkers have emphasized their importance in diagnosis. The previous studies mainly focused on micro RNAs, and only a few on extracellular vesicles, neurofilament light chain, and S100B. (4) Conclusions: The combination between salivary biomarkers, clinical history and examination, self-reported symptoms, and cognitive/balance testing can provide a non-invasive alternative diagnostic methodology, as compared to the currently approved plasma and cerebrospinal fluid biomarkers.

S100B, Actor and Biomarker of Mild Traumatic Brain Injury

Mild traumatic brain injury (mTBI) accounts for approximately 80% of all TBI cases and is a growing source of morbidity and mortality worldwide. To improve the management of children and adults with mTBI, a series of candidate biomarkers have been investigated in recent years. In this context, the measurement of blood biomarkers in the acute phase after a traumatic event helps reduce unnecessary CT scans and hospitalizations. In athletes, improved management of sports-related concussions is also sought to ensure athletes' safety. S100B protein has emerged as the most widely studied and used biomarker for clinical decision making in patients with mTBI. In addition to its use as a diagnostic biomarker, S100B plays an active role in the molecular pathogenic processes accompanying acute brain injury. This review describes S100B protein as a diagnostic tool as well as a potential therapeutic target in patients with mTBI.

Early DNase-I therapy delays secondary brain damage after traumatic brain injury in adult mice

Traumatic brain injury (TBI) causes the release of danger-associated molecular patterns (DAMP) from damaged or dead cells, which contribute to secondary brain damage after TBI. Cell-free DNA (cfDNA) is a DAMP known to cause disruption of the blood-brain barrier (BBB), promote procoagulant processes, brain edema, and neuroinflammation. This study tested the hypothesis that administration of deoxyribonuclease-I (DNase-I) has a beneficial effect after TBI. Mice (n = 84) were subjected to controlled cortical impact (CCI) and posttraumatic intraperitoneal injections of low dose (LD) or high dose (HD) of DNase-I or vehicle solution at 30 min and 12 h after CCI. LD was most effective to reduce lesion volume (p = 0.003), brain water content (p < 0.0001) and to stabilize BBB integrity (p = 0.019) 1 day post-injury (dpi). At 6 h post injury LD-treated animals showed less cleavage of fibrin (p = 0.0014), and enhanced perfusion as assessed by micro-computer-tomography (p = 0.027). At 5 dpi the number of Iba1-positive cells (p = 0.037) were reduced, but the number of CD45-positive cells, motoric function and brain lesion volume was not different. Posttraumatic-treatment with DNase-I therefore stabilizes the BBB, reduces the formation of brain edema, immune response, and delays secondary brain damage. DNase-I might be a new approach to extend the treatment window after TBI.