[Injury mechanism, clinical status and prospects of traumatic brain injury].

Traumatic brain injury (TBI) is an important in the world's public health and an important subject of basic and clinical research in the medical field. In the past 30 years, the epidemiology, injury mechanism, safety prevention, medical strategies, nursing measures and other aspects of TBI have made great progress, and the level of treatment has also been continuously improved, but it still faces many challenges. The focus of research on the injury mechanism of TBI has gradually shifted from the classic signaling pathways of primary injury to the study of secondary injury mechanisms. Pharmacological research on various therapeutic targets has also made significant progress, which is expected to be transformed into new TBI therapeutic drugs. On the other hand, many new clinical concepts, new systems, and new methods are constantly being integrated into the diagnosis and treatment of TBI, which has gradually transformed from the original treatment of acute neurological injury to the comprehensive treatment of chronic systemic diseases. This paper is based on the latest research progress in the basic and clinical aspects of TBI, and provides a review of its current status and development trends, providing reference for the medical treatment and research of TBI.

Treatment with RNase alleviates brain injury but not neuroinflammation in neonatal hypoxia/ischemia.

There is a need for new treatments to reduce brain injuries derived from neonatal hypoxia/ischemia. The only viable option used in the clinic today in infants born at term is therapeutic hypothermia, which has a limited efficacy. Treatments with exogenous RNase have shown great promise in a range of different adult animal models including stroke, ischemia/reperfusion injury, or experimental heart transplantation, often by conferring vascular protective and anti-inflammatory effects. However, any neuroprotective function of RNase treatment in the neonate remains unknown. Using a well-established model of neonatal hypoxic/ischemic brain injury, we evaluated the influence of RNase treatment on RNase activity, gray and white matter tissue loss, blood-brain barrier function, as well as levels and expression of inflammatory cytokines in the brain up to 6 h after the injury using multiplex immunoassay and RT-PCR. Intraperitoneal treatment with RNase increased RNase activity in both plasma and cerebropinal fluids. The RNase treatment resulted in a reduction of brain tissue loss but did not affect the blood-brain barrier function and had only a minor modulatory effect on the inflammatory response. It is concluded that RNase treatment may be promising as a neuroprotective regimen, whereas the mechanistic effects of this treatment appear to be different in the neonate compared to the adult and need further investigation.

Bi-directional neuro-immune dysfunction after chronic experimental brain injury.

BACKGROUND: It is well established that traumatic brain injury (TBI) causes acute and chronic alterations in systemic immune function and that systemic immune changes contribute to posttraumatic neuroinflammation and neurodegeneration. However, how TBI affects bone marrow (BM) hematopoietic stem/progenitor cells chronically and to what extent such changes may negatively impact innate immunity and neurological function has not been examined. METHODS: To further understand the role of BM cell derivatives on TBI outcome, we generated BM chimeric mice by transplanting BM from chronically injured or sham (i.e., 90 days post-surgery) congenic donor mice into otherwise healthy, age-matched, irradiated CD45.2 C57BL/6 (WT) hosts. Immune changes were evaluated by flow cytometry, multiplex ELISA, and NanoString technology. Moderate-to-severe TBI was induced by controlled cortical impact injury and neurological function was measured using a battery of behavioral tests. RESULTS: TBI induced chronic alterations in the transcriptome of BM lineage-c-Kit+Sca1+ (LSK+) cells in C57BL/6 mice, including modified epigenetic and senescence pathways. After 8 weeks of reconstitution, peripheral myeloid cells from TBI→WT mice showed significantly higher oxidative stress levels and reduced phagocytic activity. At eight months after reconstitution, TBI→WT chimeric mice were leukopenic, with continued alterations in phagocytosis and oxidative stress responses, as well as persistent neurological deficits. Gene expression analysis revealed BM-driven changes in neuroinflammation and neuropathology after 8 weeks and 8 months of reconstitution, respectively. Chimeric mice subjected to TBI at 8 weeks and 8 months post-reconstitution showed that longer reconstitution periods (i.e., time post-injury) were associated with increased microgliosis and leukocyte infiltration. Pre-treatment with a senolytic agent, ABT-263, significantly improved behavioral performance of aged C57BL/6 mice at baseline, although it did not attenuate neuroinflammation in the acutely injured brain. CONCLUSIONS: TBI causes chronic activation and progressive dysfunction of the BM stem/progenitor cell pool, which drives long-term deficits in hematopoiesis, innate immunity, and neurological function, as well as altered sensitivity to subsequent brain injury.

Protocol for a magnetic resonance imaging study of participants in the fever RCT: Does fever control prevent brain injury in malaria?

BACKGROUND: Despite eradication efforts, ~135,000 African children sustained brain injuries as a result of central nervous system (CNS) malaria in 2021. Newer antimalarial medications rapidly clear peripheral parasitemia and improve survival, but mortality remains high with no associated decline in post-malaria neurologic injury. A randomized controlled trial of aggressive antipyretic therapy with acetaminophen and ibuprofen (Fever RCT) for malarial fevers being conducted in Malawi and Zambia began enrollment in 2019. We propose to use neuroimaging in the context of the RCT to further evaluate neuroprotective effects of aggressive antipyretic therapy. METHODS: This observational magnetic resonance imaging (MRI) ancillary study will obtain neuroimaging and neurodevelopmental and behavioral outcomes in children previously enrolled in the Fever RCT at 1- and 12-months post discharge. Analysis will compare the odds of any brain injury between the aggressive antipyretic therapy and usual care groups based upon MRI structural abnormalities. For children unable to undergo imaging without deep sedation, neurodevelopmental and behavioral outcomes will be used to identify brain injury. DISCUSSION: Neuroimaging is a well-established, valid proxy for neurological outcomes after brain injury in pediatric CNS malaria. This MRI ancillary study will add value to the Fever RCT by determining if treatment with aggressive antipyretic therapy is neuroprotective in CNS malaria. It may also help elucidate the underlying mechanism(s) of neuroprotection and expand upon FEVER RCT safety assessments.

Bioinformatics-based discovery of biomarkers and immunoinflammatory targets in children with cerebral palsy: An observational study.

Cerebral palsy (CP) is the most common disabling disease in children, and motor dysfunction is the core symptom of CP. Although relevant risk factors have been found to be closely associated with CP: congenital malformations, multiple gestation, prematurity, intrauterine inflammation and infection, birth asphyxia, thrombophilia, and perinatal stroke. Its important pathophysiological mechanism is amniotic fluid infection and intraamniotic inflammation leading to fetal developing brain damage, which may last for many years. However, the molecular mechanism of CP is still not well explained. This study aimed to use bioinformatics to identify key biomarker-related signaling pathways in CP. The expression profile of children with CP was selected from the Gene Expression Comprehensive Database, and the CP disease gene data set was obtained from GeneCards. A protein-protein interaction network was established and functional enrichment analysis was performed using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases. A total of 144 differential key intersection genes and 10 hub genes were identified through molecular biology. Gene Ontology functional enrichment analysis results show that differentially expressed genes are mainly concentrated in biological processes, such as immune response and neurogenesis. The cellular components involved mainly include axons, postsynaptic membranes, etc, and their molecular functions mainly involve proteoglycan binding, collagen binding, etc. Kyoto Encyclopedia of Genes and Genomes analysis shows that the intersection genes are mainly in signaling pathways related to the immune system, inflammatory response, and nervous system, such as Th17 cell differentiation, Toll-like receptor signaling pathway, tumor necrosis factor signaling pathway, NF-κB signaling pathway, axon guidance, PI3K-Akt signaling pathway, HIF-1 signaling pathway, gap junction, etc. Jak-STAT signaling pathway, mTOR signaling pathway, and related hub genes regulate immune cells and inflammatory factors and play an important role in the development and progression of CP.

Co-designing positive behaviour support (PBS+PLUS) training resources: a qualitative study of people with ABI, close-others, and clinicians' experiences.

Background Challenging behaviours are often a significant difficulty faced following acquired brain injury (ABI), for which PBS+PLUS (a Positive Behaviour Support framework) is an effective intervention. Clinicians report experiencing a range of barriers to supporting behaviour change for individuals with ABI and require tailored resources to support the implementation of PBS+PLUS. This study aimed to describe the process of co-designing a PBS+PLUS intervention guidebook and podcast series together with individuals with ABI, close-others, and clinicians, and qualitatively examine co-design experiences. Methods The Knowledge-To-Action Framework was followed to support the translation of PBS+PLUS into clinical practice. Participants with ABI (n = 4), close-others (n = 7), and clinicians (n = 3) participated in focus groups contributing to the development of a PBS+PLUS intervention guidebook and podcast series. Following completion of the groups, qualitative interviews were conducted to understand participants' perspectives of the co-design experience. Transcripts were analysed using reflexive thematic analysis. Results Co-design processes are described, and participants provided practical suggestions for co-design and the dissemination of developed resources. Two core themes encapsulating four sub-themes were identified. Firstly, 'Esteeming Experiences ' described the person-driven approach of co-design whereby participants felt supported and connected with other contributors and facilitators through sharing their perspectives. Secondly, 'Empowerment ' reflected participants' increased confidence and skills in applying PBS+PLUS. Conclusions Overall, participants endorsed the therapeutic benefits of co-design engagement and high utility of PBS+PLUS resources. This study adds to the growing literature supporting the use of co-design methodology within clinical implementation, and is inclusive of individuals with ABI, close-others, and clinicians.

Co-developing 'The CyberABIlity Scale' to assess vulnerability to cyberscams for people with acquired brain injury: Delphi and cognitive interviews with clinicians and people with acquired brain injury.

Background Although individuals with acquired brain injury (ABI) may be vulnerable to cyberscams, the lack of existing measures documenting cybersafety behaviours in people with ABI limits our understanding of ABI-specific risk factors, the frequency of this problem, and the ability to evaluate evidence-based interventions. The CyberABIlity Scale was developed to assess vulnerability in people with ABI via self-rated statements and practical scam-identification tasks. This study aimed to develop and refine The CyberABIlity Scale through feedback from clinicians and people with ABI. Methods Scale feedback was collected via three rounds of clinician surveys (n = 14) using Delphi methods and two rounds of cognitive interviews with participants with ABI (n = 8). Following each round, feedback was quantitatively and qualitatively summarised, and revisions were made accordingly. Results Key revisions included removing 12 items deemed irrelevant. Instructions and rating scales were revised to improve clarity. Cognitive interviews identified 15 comprehension errors, with further revisions made to support response clarity for participants with ABI. Clinicians and participants with ABI endorsed the content and face validities of The CyberABIlity Scale . Conclusions Following further validation, The CyberABIlity Scale has the potential to be an effective screening measure for online vulnerability for people with ABI within clinical and research settings.

Understanding barriers and facilitators to long-term participation needs in children and young people following acquired brain injuries: a qualitative multi-stakeholder study.

Background This study focused on exploring the longer-term participation needs of children and young people with acquired brain injury (CYP-ABI) and their families in one region of the UK and identifying the barriers and facilitators of their participation and well-being to inform the development of a behavioural change intervention for clinical implementation. Methods Qualitative interviews were conducted with CYP-ABI and parents. Focus groups were created with health, education, care and charity stakeholders. The International Classification of Functioning, Disability and Health (ICF) and the Behaviour Change Wheel (BCW) were used to map needs, barriers and facilitators. Results A total of 10 CYP/parent dyads (n = 20) and 17 health, education, care and charity stakeholders were included in this study. Unmet participation needs were mapped to the ICF and barriers/facilitators to the BCW. Significant unmet needs impacting CYP-ABI participation and family well-being were found. Barriers spanned 'Capability', 'Opportunity' and 'Motivation', the greatest being knowledge, skills, social influences, environmental context and resources, social identity and emotion. Facilitators included increasing awareness and understanding, supporting parents, long-term access to specialist assessment and rehabilitation, peer support and integrated collaborative pathways. Conclusion The long-term impact of ABI on CYP and families' participation and well-being were significant, with barriers spanning every sector and level of society. Implementation of collaborative, cross-sector (education, health and social care) accessible and family-centred care pathways is needed to meet the long-term needs of CYP-ABI and their families, ensuring equity of access. Multi-modal, family-centred, needs-led, theory-based interventions should be co-developed with CYP, families and stakeholders to improve the health and well-being outcomes and the lives of CYP-ABI and their families.

Functional brain networks in Developmental Topographical Disorientation.

Despite a decade-long study on Developmental Topographical Disorientation, the underlying mechanism behind this neurological condition remains unknown. This lifelong selective inability in orientation, which causes these individuals to get lost even in familiar surroundings, is present in the absence of any other neurological disorder or acquired brain damage. Herein, we report an analysis of the functional brain network of individuals with Developmental Topographical Disorientation ($n = 19$) compared against that of healthy controls ($n = 21$), all of whom underwent resting-state functional magnetic resonance imaging, to identify if and how their underlying functional brain network is altered. While the established resting-state networks (RSNs) are confirmed in both groups, there is, on average, a greater connectivity and connectivity strength, in addition to increased global and local efficiency in the overall functional network of the Developmental Topographical Disorientation group. In particular, there is an enhanced connectivity between some RSNs facilitated through indirect functional paths. We identify a handful of nodes that encode part of these differences. Overall, our findings provide strong evidence that the brain networks of individuals suffering from Developmental Topographical Disorientation are modified by compensatory mechanisms, which might open the door for new diagnostic tools.

Mitochondrial Calcium Uniporter (MCU) is Involved in an Ischemic Postconditioning Effect Against Ischemic Reperfusion Brain Injury in Mice.

The phenomenon of ischemic postconditioning (PostC) is known to be neuroprotective against ischemic reperfusion (I/R) injury. One of the key processes in PostC is the opening of the mitochondrial ATP-dependent potassium (mito-KATP) channel and depolarization of the mitochondrial membrane, triggering the release of calcium ions from mitochondria through low-conductance opening of the mitochondrial permeability transition pore. Mitochondrial calcium uniporter (MCU) is known as a highly sensitive transporter for the uptake of Ca2+ present on the inner mitochondrial membrane. The MCU has attracted attention as a new target for treatment in diseases, such as neurodegenerative diseases, cancer, and ischemic stroke. We considered that the MCU may be involved in PostC and trigger its mechanisms. This research used the whole-cell patch-clamp technique on hippocampal CA1 pyramidal cells from C57BL mice and measured changes in spontaneous excitatory post-synaptic currents (sEPSCs), intracellular Ca2+ concentration, mitochondrial membrane potential, and N-methyl-D-aspartate receptor (NMDAR) currents under inhibition of MCU by ruthenium red 265 (Ru265) in PostC. Inhibition of MCU increased the occurrence of sEPSCs (p = 0.014), NMDAR currents (p < 0.001), intracellular Ca2+ concentration (p < 0.001), and dead cells (p < 0.001) significantly after reperfusion, reflecting removal of the neuroprotective effects in PostC. Moreover, mitochondrial depolarization in PostC with Ru265 was weakened, compared to PostC (p = 0.004). These results suggest that MCU affects mitochondrial depolarization in PostC to suppress NMDAR over-activation and prevent elevation of intracellular Ca2+ concentrations against I/R injury.

Shared inflammatory glial cell signature after stab wound injury, revealed by spatial, temporal, and cell-type-specific profiling of the murine cerebral cortex.

Traumatic brain injury leads to a highly orchestrated immune- and glial cell response partially responsible for long-lasting disability and the development of secondary neurodegenerative diseases. A holistic understanding of the mechanisms controlling the responses of specific cell types and their crosstalk is required to develop an efficient strategy for better regeneration. Here, we combine spatial and single-cell transcriptomics to chart the transcriptomic signature of the injured male murine cerebral cortex, and identify specific states of different glial cells contributing to this signature. Interestingly, distinct glial cells share a large fraction of injury-regulated genes, including inflammatory programs downstream of the innate immune-associated pathways Cxcr3 and Tlr1/2. Systemic manipulation of these pathways decreases the reactivity state of glial cells associated with poor regeneration. The functional relevance of the discovered shared signature of glial cells highlights the importance of our resource enabling comprehensive analysis of early events after brain injury.

Repetitive transcranial magnetic stimulation ameliorates cognitive deficits in mice with radiation-induced brain injury by attenuating microglial pyroptosis and promoting neurogenesis via BDNF pathway.

BACKGROUND: Radiation-induced brain injury (RIBI) is a common and severe complication during radiotherapy for head and neck tumor. Repetitive transcranial magnetic stimulation (rTMS) is a novel and non-invasive method of brain stimulation, which has been applied in various neurological diseases. rTMS has been proved to be effective for treatment of RIBI, while its mechanisms have not been well understood. METHODS: RIBI mouse model was established by cranial irradiation, K252a was daily injected intraperitoneally to block BDNF pathway. Immunofluorescence staining, immunohistochemistry and western blotting were performed to examine the microglial pyroptosis and hippocampal neurogenesis. Behavioral tests were used to assess the cognitive function and emotionality of mice. Golgi staining was applied to observe the structure of dendritic spine in hippocampus. RESULTS: rTMS significantly promoted hippocampal neurogenesis and mitigated neuroinflammation, with ameliorating pyroptosis in microglia, as well as downregulation of the protein expression level of NLRP3 inflammasome and key pyroptosis factor Gasdermin D (GSDMD). BDNF signaling pathway might be involved in it. After blocking BDNF pathway by K252a, a specific BDNF pathway inhibitor, the neuroprotective effect of rTMS was markedly reversed. Evaluated by behavioral tests, the cognitive dysfunction and anxiety-like behavior were found aggravated with the comparison of mice in rTMS intervention group. Moreover, the level of hippocampal neurogenesis was found to be attenuated, the pyroptosis of microglia as well as the levels of GSDMD, NLRP3 inflammasome and IL-1ß were upregulated. CONCLUSION: Our study indicated that rTMS notably ameliorated RIBI-induced cognitive disorders, by mitigating pyroptosis in microglia and promoting hippocampal neurogenesis via mediating BDNF pathway.

Luteolin-7-O-ß-d-glucuronide Ameliorates Cerebral Ischemic Injury: Involvement of RIP3/MLKL Signaling Pathway.

Luteolin-7-O-ß-d-glucuronide (LGU) is a major active flavonoid glycoside compound that is extracted from Ixeris sonchifolia (Bge.) Hance, and it is a Chinese medicinal herb mainly used for the treatment of coronary heart disease, angina pectoris, cerebral infarction, etc. In the present study, the neuroprotective effect of LGU was investigated in an oxygen glucose deprivation (OGD) model and a middle cerebral artery occlusion (MCAO) rat model. In vitro, LGU was found to effectively improve the OGD-induced decrease in neuronal viability and increase in neuronal death by a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and a lactate dehydrogenase (LDH) leakage rate assay, respectively. LGU was also found to inhibit OGD-induced intracellular Ca2+ overload, adenosine triphosphate (ATP) depletion, and mitochondrial membrane potential (MMP) decrease. By Western blotting analysis, LGU significantly inhibited the OGD-induced increase in expressions of receptor-interacting serine/threonine-protein kinase 3 (RIP3) and mixed lineage kinase domain-like protein (MLKL). Moreover, molecular docking analysis showed that LGU might bind to RIP3 more stably and firmly than the RIP3 inhibitor GSK872. Immunofluorescence combined with confocal laser analyses disclosed that LGU inhibited the aggregation of MLKL to the nucleus. Our results suggest that LGU ameliorates OGD-induced rat primary cortical neuronal injury via the regulation of the RIP3/MLKL signaling pathway in vitro. In vivo, LGU was proven, for the first time, to protect the cerebral ischemia in a rat middle cerebral artery occlusion (MCAO) model, as shown by improved neurological deficit scores, infarction volume rate, and brain water content rate. The present study provides new insights into the therapeutic potential of LGU in cerebral ischemia.

The effectiveness and safety of centralized early rehabilitation care for critically ill children with severe acquired brain injury: A retrospective cohort and implementation study.

BACKGROUND: Most children with neurocritical illness are at risk of physical, neurocognitive, and psychosocial sequelae and need centralized early rehabilitation care. OBJECTIVE: To identify the effectiveness and safety of centralized early rehabilitation care for children with severe acquired brain injury. METHODS: This is a mixed methods study-an implementation study and single-center retrospective cohort study with historical control. All children with severe acquired brain injury hospitalized in a specialized rehabilitation center in a comprehensive tertiary pediatric hospital between September 2016 and August 2020 were included. Patients treated in the centralized early rehabilitation unit were compared to historical controls dispersed in the normal inpatient rehabilitation ward. The effectiveness outcomes were measured by the Pediatric Cerebral Performance Category (PCPC) scale and the incidence of newly onset comorbidities. The safety outcomes were indicated by the mortality rate and the incidence of unexpected referrals. RESULTS: One hundred seventy-five patients were included. The delta PCPC scores of the first 4 weeks of inpatient rehabilitation in the intervention group were significantly lower than the control group (Z = -2.395, p = 0.017). The PCPC scores at 1 year in the intervention group were significantly reduced as compared to the control group (Z = -3.337, p = 0.001). The incidence of newly onset pneumonia/bronchitis was also decreased in the intervention group (χ2 = 4.517, p = 0.034). No death of patients was recorded, and there was no significant difference in unexpected referral rate between the two groups (χ2 = 0.374, p = 0.541). CONCLUSIONS: The centralized pediatrics early rehabilitation unit is effective and safe for children with severe acquired brain injury. Further multicenter prospective implementation studies on effectiveness, safety, and economic evaluation are needed.

Brain magnetic resonance imaging review suggests unrecognised hypoglycaemia in childhood.

Introduction: Neonatal and early-life hypoglycaemia, is a frequent finding but is often non-specific and asymptomatic, making detection and diagnosis challenging. Hypoglycaemia-induced cerebral injury can be identified by magnetic resonance imaging (MRI) changes in cerebral white matter, occipital lobes, and posterior parietotemporal regions. It is unknown if children may have hypoglycaemic brain injury secondary to unrecognised hypoglycaemia in early life. We have examined retrospective radiological findings of likely brain injury by neuroimaging to investigate the existence of previous missed hypoglycaemic events. Methods: Retrospective MRI data in children in a single tertiary centre, over a ten-year period was reviewed to identify potential cases of unrecognised early-life hypoglycaemia. A detailed search from an electronic radiology repository involved the term "hypoglycaemia'' from text-based reports. The initial report was used for those who required serial scanning. Images specific to relevant reports were further reviewed by a designated paediatric neuroradiologist to confirm likely hypoglycaemia induced brain injury. Medical records of those children were subsequently reviewed to assess if the hypoglycaemia had been diagnosed prior to imaging. Results: A total of 107 MR imaging reports were identified for review, and 52 (48.5%) showed typical features strongly suggestive of hypoglycaemic brain injury. Medical note review confirmed no documented clinical information of hypoglycaemia prior to imaging in 22 (42%) patients, raising the likelihood of missed hypoglycaemic events resulting in brain injury. Conclusions: We have identified the existence of unrecognised childhood hypoglycaemia through neuroimaging review. This study highlights the need for heightened awareness of early life hypoglycaemia to prevent adverse neurological outcomes later in childhood.

Hyperoxia and brain: the link between necessity and injury from a molecular perspective.

Oxygen (O2) supplementation is commonly used to treat hypoxia in patients with respiratory failure. However, indiscriminate use can lead to hyperoxia, a condition detrimental to living tissues, particularly the brain. The brain is sensitive to reactive oxygen species (ROS) and inflammation caused by high concentrations of O2, which can result in brain damage and mitochondrial dysfunction, common features of neurodegenerative disorders. Hyperoxia leads to increased production of ROS, causing oxidative stress, an imbalance between oxidants and antioxidants, which can damage tissues. The brain is particularly vulnerable to oxidative stress due to its lipid composition, high O2 consumption rate, and low levels of antioxidant enzymes. Moreover, hyperoxia can cause vasoconstriction and decreased O2 supply to the brain, posing a challenge to redox balance and neurodegenerative processes. Studies have shown that the severity of hyperoxia-induced brain damage varies with inspired O2 concentration and duration of exposure. Therefore, careful evaluation of the balance between benefits and risks of O2 supplementation, especially in clinical settings, is crucial.