Global neurotrauma research challenges and opportunities. Nature. 2015;527:S193-S197. [PMID: 26580327 DOI: 10.1038/nature16035]

Estimating the global incidence of traumatic brain injury

OBJECTIVE

Traumatic brain injury (TBI)-the "silent epidemic"-contributes to worldwide death and disability more than any other traumatic insult. Yet, TBI incidence and distribution across regions and socioeconomic divides remain unknown. In an effort to promote advocacy, understanding, and targeted intervention, the authors sought to quantify the case burden of TBI across World Health Organization (WHO) regions and World Bank (WB) income groups.

METHODS

Open-source epidemiological data on road traffic injuries (RTIs) were used to model the incidence of TBI using literature-derived ratios. First, a systematic review on the proportion of RTIs resulting in TBI was conducted, and a meta-analysis of study-derived proportions was performed. Next, a separate systematic review identified primary source studies describing mechanisms of injury contributing to TBI, and an additional meta-analysis yielded a proportion of TBI that is secondary to the mechanism of RTI. Then, the incidence of RTI as published by the Global Burden of Disease Study 2015 was applied to these two ratios to generate the incidence and estimated case volume of TBI for each WHO region and WB income group.

RESULTS

Relevant articles and registries were identified via systematic review; study quality was higher in the high-income countries (HICs) than in the low- and middle-income countries (LMICs). Sixty-nine million (95% CI 64-74 million) individuals worldwide are estimated to sustain a TBI each year. The proportion of TBIs resulting from road traffic collisions was greatest in Africa and Southeast Asia (both 56%) and lowest in North America (25%). The incidence of RTI was similar in Southeast Asia (1.5% of the population per year) and Europe (1.2%). The overall incidence of TBI per 100,000 people was greatest in North America (1299 cases, 95% CI 650-1947) and Europe (1012 cases, 95% CI 911-1113) and least in Africa (801 cases, 95% CI 732-871) and the Eastern Mediterranean (897 cases, 95% CI 771-1023). The LMICs experience nearly 3 times more cases of TBI proportionally than HICs.

CONCLUSIONS

Sixty-nine million (95% CI 64-74 million) individuals are estimated to suffer TBI from all causes each year, with the Southeast Asian and Western Pacific regions experiencing the greatest overall burden of disease. Head injury following road traffic collision is more common in LMICs, and the proportion of TBIs secondary to road traffic collision is likewise greatest in these countries. Meanwhile, the estimated incidence of TBI is highest in regions with higher-quality data, specifically in North America and Europe.

Hypochloremia in Patients with Severe Traumatic Brain Injury: A Possible Risk Factor for Increased Mortality

OBJECTIVE

To determine association between electrolyte disturbances and mortality in patients with severe traumatic brain injury.

METHODS

Medical records of patients with severe traumatic brain injury and Glasgow Coma Scale score <8 and electrolyte alterations were reviewed in a retrospective cohort study. Electrolyte levels were analyzed to establish an association between patients who died and patients who survived. Bivariate analysis was performed using χ² test with a statistical reliability of 95% for categorical variables. Analysis for electrolyte changes to determine association with mortality was performed using χ² test with multiple comparisons. Logistic regression was performed between the electrolyte alterations and their association with mortality. The reliability of statistical tests was 95%.

RESULTS

There was a significant relationship between hypochloremia and increased risk of mortality in 23.1% of deceased patients (P = 0.03). Furthermore, there was a significant correlation with age (P < 0.01) and with the Acute Physiology and Chronic Health Evaluation APACHE II (P < 0.01).

CONCLUSIONS

Hypochloremia could be an important prognostic factor to determine mortality risk and to improve treatment in patients with severe traumatic brain injury.

Changes in Plasma von Willebrand Factor and Cellular Fibronectin in MRI-Defined Traumatic Microvascular Injury

The neuropathology of traumatic brain injury (TB) is diverse, including primary injury to neurons, axons, glial cells, vascular structures, and secondary processes, such as edema and inflammation that vary between individual patients. Traumatic microvascular injury is an important endophenotype of TBI-related injury. We studied patients who sustained a TBI requiring ER evaluation and had an MRI performed within 48 h of injury. We classified patients into 3 groups based on their MRI findings: (1) those that had evidence of traumatic microvascular injury on susceptibility or diffusion weighted MRI sequences without frank hemorrhage [Traumatic Vascular Injury (TVI) group; 20 subjects]. (2) those who had evidence of intraparenchymal, subdural, epidural, or subarachnoid hemorrhage [Traumatic Hemorrhage (TH) group; 26 subjects], and (3) those who had no traumatic injuries detected by MRI [MRI-negative group; 30 subjects]. We then measured plasma protein biomarkers of vascular injury [von Willebrand Factor (vWF) or cellular fibronectin (cFn)] and axonal injury (phosphorylated neurofilament heavy chain; pNF-H). We found that the TVI group was characterized by decreased expression of plasma vWF (p < 0.05 compared to MRI-negative group; p < 0.00001 compared to TH group) ≤48 h after injury. cFN was no different between groups ≤48 h after injury, but was increased in the TVI group compared to the MRI-negative (p < 0.00001) and TH (p < 0.00001) groups when measured >48 h from injury. pNF-H was increased in both the TH and TVI groups compared to the MRI-negative group ≤48 h from injury. When we used the MRI grouping and molecular biomarkers in a model to predict Glasgow Outcome Scale-Extended (GOS-E) score at 30–90 days, we found that inclusion of the imaging data and biomarkers substantially improved the ability to predict a good outcome over clinical information alone. These data indicate that there is a distinct, vascular-predominant endophenotype in a subset of patients who sustain a TBI and that these injuries are characterized by a specific biomarker profile. Further work to will be needed to determine whether these biomarkers can be useful as predictive and pharmacodynamic biomarkers for vascular-directed therapies after TBI.

A scalable solution for isolating human multipotent clinical-grade neural stem cells from ES precursors

Background

A well-characterized method has not yet been established to reproducibly, efficiently, and safely isolate large numbers of clinical-grade multipotent human neural stem cells (hNSCs) from embryonic stem cells (hESCs). Consequently, the transplantation of neurogenic/gliogenic precursors into the CNS for the purpose of cell replacement or neuroprotection in humans with injury or disease has not achieved widespread testing and implementation.

Methods

Here, we establish an approach for the in vitro isolation of a highly expandable population of hNSCs using the manual selection of neural precursors based on their colony morphology (CoMo-NSC). The purity and NSC properties of established and extensively expanded CoMo-NSC were validated by expression of NSC markers (flow cytometry, mRNA sequencing), lack of pluripotent markers and by their tumorigenic/differentiation profile after in vivo spinal grafting in three different animal models, including (i) immunodeficient rats, (ii) immunosuppressed ALS rats (SOD1_G93A), or (iii) spinally injured immunosuppressed minipigs.

Results

In vitro analysis of established CoMo-NSCs showed a consistent expression of NSC markers (Sox1, Sox2, Nestin, CD24) with lack of pluripotent markers (Nanog) and stable karyotype for more than 15 passages. Gene profiling and histology revealed that spinally grafted CoMo-NSCs differentiate into neurons, astrocytes, and oligodendrocytes over a 2–6-month period in vivo without forming neoplastic derivatives or abnormal structures. Moreover, transplanted CoMo-NSCs formed neurons with synaptic contacts and glia in a variety of host environments including immunodeficient rats, immunosuppressed ALS rats (SOD1G93A), or spinally injured minipigs, indicating these cells have favorable safety and differentiation characteristics.

Conclusions

These data demonstrate that manually selected CoMo-NSCs represent a safe and expandable NSC population which can effectively be used in prospective human clinical cell replacement trials for the treatment of a variety of neurodegenerative disorders, including ALS, stroke, spinal traumatic, or spinal ischemic injury.

Electronic supplementary material

The online version of this article (10.1186/s13287-019-1163-7) contains supplementary material, which is available to authorized users.

Synthesis and Characterization of a Silica-Based Drug Delivery System for Spinal Cord Injury Therapy

Acute inflammation is a central component in the progression of spinal cord injury (SCI). Anti-inflammatory drugs used in the clinic are often administered systemically at high doses, which can paradoxically increase inflammation and result in drug toxicity. A cluster-like mesoporous silica/arctigenin/CAQK composite (MSN-FC@ARC-G) drug delivery system was designed to avoid systemic side effects of high-dose therapy by enabling site-specific drug delivery to the spinal cord. In this nanosystem, mesoporous silica was modified with the FITC fluorescent molecule and CAQK peptides that target brain injury and SCI sites. The size of the nanocarrier was kept at approximately 100 nm to enable penetration of the blood-brain barrier. Arctigenin, a Chinese herbal medicine, was loaded into the nanosystem to reduce inflammation. The in vivo results showed that MSN-FC@ARC-G could attenuate inflammation at the injury site. Behavior and morphology experiments suggested that MSN-FC@ARC-G could diminish local microenvironment damage, especially reducing the expression of interleukin-17 (IL-17) and IL-17-related inflammatory factors, inhibiting the activation of astrocytes, thus protecting neurons and accelerating the recovery of SCI. Our study demonstrated that this novel, silica-based drug delivery system has promising potential for clinical application in SCI therapy.

Metabolism and inflammation: implications for traumatic brain injury therapeutics

INTRODUCTION

Traumatic Brain Injury (TBI) is a leading cause of death and disability in young people, affecting 69 million people annually, worldwide. The initial trauma disrupts brain homeostasis resulting in metabolic dysfunction and an inflammatory cascade, which can then promote further neurodegenerative effects for months or years, as a 'secondary' injury. Effective targeting of the cerebral inflammatory system is challenging due to its complex, pleiotropic nature. Cell metabolism plays a key role in many diseases, and increased disturbance in the TBI metabolic state is associated with poorer patient outcomes. Investigating critical metabolic pathways, and their links to inflammation, can potentially identify supplements which alter the brain's long-term response to TBI and improve recovery. Areas covered: The authors provide an overview of literature on metabolism and inflammation following TBI, and from relevant pre-clinical and clinical studies, propose therapeutic strategies. Expert opinion: There is still no specific active drug treatment for TBI. Changes in metabolic and inflammatory states have been reported after TBI and appear linked. Understanding more about abnormal cerebral metabolism following TBI, and its relationship with cerebral inflammation, will provide essential information for designing therapies, with implications for neurocritical care and for alleviating long-term disability and neurodegeneration in post-TBI patients.

Proteomics analysis of Schwann cell-derived exosomes: a novel therapeutic strategy for central nervous system injury

Exosomes are nanometer-sized vesicles involved in intercellular communication, and they are released by various cell types. To learn about exosomes produced by Schwann cells (SCs) and to explore their potential function in repairing the central nervous system (CNS), we isolated exosomes from supernatants of SCs by ultracentrifugation, characterized them by electron microscopy and immunoblotting and determined their protein profile using proteomic analysis. The results demonstrated that Schwann cell-derived exosomes (SCDEs) were, on average, 106.5 nm in diameter, round, and had cup-like concavity and expressed exosome markers CD9 and Alix but not tumor susceptibility gene (TSG) 101. We identified a total of 433 proteins, among which 398 proteins overlapped with the ExoCarta database. According to their specific functions, we identified 12 proteins that are closely related to CNS repair and classified them by different potential mechanisms, such as axon regeneration and inflammation inhibition. Gene Oncology analysis indicated that SCDEs are mainly involved in signal transduction and cell communication. Biological pathway analysis showed that pathways are mostly involved in exosome biogenesis, formation, uptake and axon regeneration. Among the pathways, the neurotrophin, PI3K-Akt and cAMP signaling pathways played important roles in CNS repair. Our study isolated SCDEs, unveiled their contents, presented potential neurorestorative proteins and pathways and provided a rich proteomics data resource that will be valuable for future studies of the functions of individual proteins in neurodegenerative diseases.

Injury-to-Admission Delay Beyond 4 Hours Is Associated with Worsening Outcomes for Traumatic Brain Injury in Cambodia

BACKGROUND

In Cambodia, the most common victims of traumatic brain injury (TBI) are men 20-30 years of age involved in motor vehicle collision. Secondary injury sustained by these patients occurs during the time period between initial insult and hospital admission. Strengthening prehospital systems for TBI in low- and middle-income countries (LMICs) such as Cambodia is therefore a key element of the development agenda for universal health equity. We report a retrospective analysis of the relationship between prehospital delays and TBI outcomes among patients from a large government hospital in Cambodia.

METHODS

Data were collected from 3476 patients with TBI admitted to a major government hospital in Phnom Penh, Cambodia, from June 2013 to June 2018. Patients with missing data or those admitted >8 hours postinjury were excluded. Statistical analyses examined associations between injury-to-admission delay (IAD) and outcomes such as Glasgow Outcome Scale (GOS) score and length of stay (LOS).

RESULTS

A total of 2125 patients with TBI (76.85% men) were included. The median age was 27 years (interquartile range, 22-37 years). Injury severity at presentation included 1406 mild (66%), 464 moderate (22%), and 240 severe cases (11%). No Glasgow Coma Scale (GCS) data were available for 15 patients (1%). We found an inverse relationship between IAD and GOS score, most evidently for mild and moderate TBI (n = 1870; 88%). Regression analysis revealed a marked decrease in GOS score at the IAD >4-hour threshold. Each 30-minute delay in IAD was correlated with >2-hour increase in LOS for mild (P < 0.001) and moderate TBI (P < 0.001).

CONCLUSIONS

In a retrospective cohort of >2000 patients with TBI from Cambodia, we found that increasing IAD was associated with worsening outcome, especially beyond the 4-hour threshold. These data should inform development of prehospital guidelines for TBI care in LMICs.

Enduring Neuroprotective Effect of Subacute Neural Stem Cell Transplantation After Penetrating TBI

Traumatic brain injury (TBI) is the largest cause of death and disability of persons under 45 years old, worldwide. Independent of the distribution, outcomes such as disability are associated with huge societal costs. The heterogeneity of TBI and its complicated biological response have helped clarify the limitations of current pharmacological approaches to TBI management. Five decades of effort have made some strides in reducing TBI mortality but little progress has been made to mitigate TBI-induced disability. Lessons learned from the failure of numerous randomized clinical trials and the inability to scale up results from single center clinical trials with neuroprotective agents led to the formation of organizations such as the Neurological Emergencies Treatment Trials (NETT) Network, and international collaborative comparative effectiveness research (CER) to re-orient TBI clinical research. With initiatives such as TRACK-TBI, generating rich and comprehensive human datasets with demographic, clinical, genomic, proteomic, imaging, and detailed outcome data across multiple time points has become the focus of the field in the United States (US). In addition, government institutions such as the US Department of Defense are investing in groups such as Operation Brain Trauma Therapy (OBTT), a multicenter, pre-clinical drug-screening consortium to address the barriers in translation. The consensus from such efforts including "The Lancet Neurology Commission" and current literature is that unmitigated cell death processes, incomplete debris clearance, aberrant neurotoxic immune, and glia cell response induce progressive tissue loss and spatiotemporal magnification of primary TBI. Our analysis suggests that the focus of neuroprotection research needs to shift from protecting dying and injured neurons at acute time points to modulating the aberrant glial response in sub-acute and chronic time points. One unexpected agent with neuroprotective properties that shows promise is transplantation of neural stem cells. In this review we present (i) a short survey of TBI epidemiology and summary of current care, (ii) findings of past neuroprotective clinical trials and possible reasons for failure based upon insights from human and preclinical TBI pathophysiology studies, including our group's inflammation-centered approach, (iii) the unmet need of TBI and unproven treatments and lastly, (iv) present evidence to support the rationale for sub-acute neural stem cell therapy to mediate enduring neuroprotection.

Geographical Disparity and Traumatic Brain Injury in America: Rural Areas Suffer Poorer Outcomes

INTRODUCTION

Significant heterogeneity exists in traumatic brain injury (TBI) outcomes. In the United States, TBI remains a primary driver of injury-related mortality and morbidity. Prior work has suggested that disparity exists in rural areas; our objective was to evaluate potential differences in TBI mortality across urban and rural areas on a national scale.

METHODS

Age-adjusted TBI fatality rates were obtained at the county level across the U.S. from 2008 to 2014. To evaluate geography, urban influence codes (UIC) were also obtained at the county level. UIC codes range from 1 (most urban) to 12 (most rural). Metropolitan counties are defined as those with an UIC ≤2, while nonmetropolitan counties are defined as an UIC ≥3. County-level fatality rates and UIC classification were geospatially mapped. Linear regression was used to evaluate the change in TBI fatality rate at each category of UIC. The median TBI fatality rate was also compared between metropolitan and nonmetropolitan counties.

RESULTS

Geospatial analysis demonstrated higher fatality rates distributed among nonmetropolitan counties across the United States. The TBI fatality rate was 13.00 deaths per 100,000 persons higher in the most rural UIC category compared to the most urban UIC category (95% confidence interval 12.15, 13.86; P < 0.001). The median TBI rate for nonmetropolitan counties was significantly higher than metropolitan counties (22.32 vs. 18.22 deaths per 100,000 persons, P < 0.001).

CONCLUSIONS

TBI fatality rates are higher in rural areas of the United States. Additional studies to evaluate the mechanisms and solutions to this disparity are warranted and may have implications for lower-and middle-income countries.

Effect of hypoxia on mortality and disability in traumatic brain injury according to shock status: A cross-sectional analysis

OBJECTIVES

This study aimed to test the association between hypoxia level and outcomes according to shock status in traumatic brain injury (TBI) patients.

METHODS

Adult TBI patients transported by emergency medical services in 10 provinces were enrolled. Hypoxia was a main exposure; three groups by oxygen saturation (SaO2, non-hypoxia (≥94%), mild hypoxia (90 ≤ SaO2 < 94%)), and severe hypoxia (<90%). Shock status (<systolic blood pressure 90 mmHg) was an interactive exposure. The outcomes were hospital mortality and worsened disability (a 2-point increase of Glasgow Outcome Scale). Multivariable logistic regression was used to calculate the adjusted odds (AORs) with 95% Confidence intervals (CIs).

RESULTS

Of the 6125 patients, the mortality/disability rates were 49.4%/69.0% in severe hypoxia, 30.7%/46.9% in mild hypoxia, and 18.5%/27.5% in normoxia (p < 0.0001). Mortality/disability rates were 47.1%/57.1% in shock status and 20.5%/31.4% in non-shock status (p < 0.0001). AORs (95% CIs) for worsened disability/mortality compared with normoxia (reference) were 3.23 (2.47-4.21)/2.24 (1.70-2.96) in patients with severe hypoxia and 2.11 (1.63-2.74)/1.84 (1.39-2.45) in those with mild hypoxia. AORs (95% CIs) for worsened disability/mortality was 1.58 (1.20-2.09)/1.33 (1.01-1.76) by severe hypoxia than normoxia in patient with only non-shock status in the interaction analysis.

CONCLUSIONS

There was a trend toward worsened outcomes with mild and severe hypoxia in patient with and without shock, however, the only met statistical significance for patients with both severe hypoxia and non-shock status.

Overexpression of kynurenic acid and 3-hydroxyanthranilic acid after rat traumatic brain injury

Using an immunohistochemical technique, we have studied the distribution of kynuneric acid (KYNA) and 3-hydroxyanthranilic acid (3-HAA) in a rat brain injury model (trauma). The study was carried out inducing a cerebral ablation of the frontal motor cortex. Two mouse monoclonal specific antibodies previously developed by our group directed against KYNA and 3-HAA were used. In control animals (sham-operated), the expression of both KYNA and 3-HAA was not observed. In animals in which the ablation was performed, the highest number of immunoreactive cells containing KYNA or 3-HAA was observed in the region surrounding the lesion and the number of these cells decreased moving away from the lesion. KYNA and 3-HAA were also observed in the white matter (ipsilateral side) located close to the injured region and in some cells placed in the white matter of the contralateral side. The distribution of KYNA and 3-HAA perfectly matched with the peripheral injured regions. The results found were identical independently of the perfusion date of animals (17, 30 or 54 days after brain injury). For the first time, the presence of KYNA and 3-HAA has been described in a rat trauma model. Moreover, by using a double immunocytochemistry protocol, it has been demonstrated that both metabolites were located in astrocytes. The findings observed suggest that, in cerebral trauma, KYNA and 3-HAA are involved in tissue damage and that these compounds could act, respectively, as a neuroprotector and a neurotoxic. This means that, in trauma, a counterbalance occurs and that a regulation of the indoleamine 2,3 dioxygenase (IDO) pathway could be required after a brain injury in order to decrease the deleterious effects of ending metabolites (the neurotoxic picolinic acid). Moreover, the localization of KYNA and 3-HAA in the contralateral side of the lesion suggests that the IDO pathway is also involved in the sprouting and pathfinding that follows a traumatic brain injury.

Bone marrow stromal cells improved functional recovery in spinal cord injury rats partly via the Toll-like receptor-4/nuclear factor-κB signaling pathway

Spinal cord injury (SCI) results in inflammation, and TLR4, which is an inflammatory factor, has an important role in the pathological injury that occurs following SCI. Recently, bone marrow stromal cells (BMSCs) have been demonstrated to be a novel treatment in SCI. However, the underlying mechanism of neuroprotection in SCI by BMSCs remains unclear. The present study was designed to investigate the therapeutic mechanism of BMSCs in SCI by analysis of Toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) expression. The present results demonstrated that BMSC transplantation promoted functional recovery and tissue repair in SCI rats. Interestingly, it also reduced the expression of TLR4 and NF-κB after SCI. Furthermore, it was demonstrated that BMSCs downregulated the expression of apoptosis factor caspase-12 in the SCI rat model. The present results demonstrated that BMSCs may have incorporated into the spinal cord to improve locomotor function after SCI, partly via the TLR4/NF-κB signaling pathway. To the best of our knowledge, this is the first study to determine that BMSCs prevented secondary injury and enhanced functional recovery in SCI via inhibition of TLR4/NF-κB-mediated inflammation.

Development of a motor and somatosensory evoked potentials-guided spinal cord Injury model in non-human primates

Background Nonhuman primates (NHP) may provide the most adequate (in terms of neuroanatomy and neurophysiology) model of spinal cord injury (SCI) for testing regenerative therapies, but bioethical considerations exclude their use in severe SCI. New Method A reproducible model of SCI at the lower thoracic level has been developed in Rhesus macaques. The model comprises surgical resection of 25% of the spinal cord in the projection of the dorsal funiculus and dorsolateral corticospinal pathways, controlled via registration of intraoperative evoked potentials (EPs). The animals were evaluated using the modified Hindlimb score, MRI, SSEP, and MEP over a time period of 8-12 weeks post-SCI, followed by histological examination. Results Complete disappearance of intraoperative EPs from distal hindlimb muscles without restoration within two weeks post-SCI was an indicator for irreversible disruption of the abovementioned pathways. As a result, controlled damage to the spinal cord was achieved in three NHPs, clinically manifested as irreversible lower monoplegia. No significant functional restoration was observed in these NHPs up to 12 weeks post-SCI. Demyelination of the damaged ascending tracts was detected. Disturbances in pelvic organ function were not observed in all animals. Comparison with existing methods The new method of EPs-guided SCI allows a more controlled and irreversible damage to the spinal cord compared with contusion and other transection approaches. Conclusions This method to induce complete SCI in NHP is well tolerated, reproducible and ethically acceptable: these are valuable attributes in a preclinical model that will hopefully help advance testing of new regenerative therapies in SCI.

A systems approach to trauma care in Myanmar: from health partnership to academic collaboration

Experience from a variety of disciplines suggests that improving healthcare, particularly in resource-poor environments, can benefit from a systems approach. However, putting this into practice is challenging, especially in the context of an international institutional health partnership. In this article, we outline how a systems approach to the improvement of trauma care has informed both clinical improvement and academic collaboration as part of an ongoing partnership involving Cambridge University Hospitals NHS Foundation Trust, the University of Cambridge, and Cambridge Global Health Partnerships in the UK, and Yangon General Hospital, University of Medicine 1, and the Tropical Health and Education Trust (THET) in Myanmar. Improving and researching trauma care is an exemplar of a systems problem, requiring an understanding of the relevant people, equipment, processes, institutions, and power structures that result in the delivery of care at all points of the patient's journey from injury to rehabilitation. Exploring this in the explicit context of traumatic brain injury is one of the research themes of the NIHR Global Health Research Group on Neurotrauma, allowing systems research to directly inform efforts at practical improvement.

Traumatic spinal cord injury in the north-east Tanzania - describing incidence, etiology and clinical outcomes retrospectively

Background: Causes, magnitude and consequences of traumatic spinal cord injury depend largely on geography, infrastructure, socioeconomic and cultural activities of a given region. There is a scarcity of literature on profile of traumatic spinal cord injury to inform prevention and rehabilitation of this health condition in African rural settings, particularly Tanzania.

Objective: To describe the incidence, etiology and clinical outcomes of traumatic spinal cord injury and issues related to retrospective study in underdeveloped setting.

Methods: Records for patients with traumatic spinal cord injury for five consecutive years (2010–2014) were obtained retrospectively from the admission wards and health records archives of the Kilimanjaro Christian Medical Center. Sociodemographic, cause, complications and patients’ condition on discharge were recorded and analyzed descriptively.

Results: The admission books in the wards registered 288 new traumatic spinal cord injury cases from January 2010 to December 2014. Of the 288 cases registered in the books, 224 were males and 64 females with mean age 39.1(39.1 ± 16.3) years and the majority of individuals 196(68.1%) were aged between 16 and 45 years. A search of the hospital archives provided 213 full patient records in which the leading cause of injury was falls 104(48.8%) followed by road traffic accidents 73(34.3%). Cervical 81(39.9%) and lumbar 71(34.74%) spinal levels were the most affected. The annual incidence for the Kilimanjaro region (population 1,640,087) was estimated at more than 26 persons per million population. The most documented complications were pressure ulcers 42(19.7%), respiratory complications 32(15.0%) and multiple complications 28(13.1%). The mean length of hospital stay was 64.2 ± 54.3 days and the mortality rate was 24.4%.

Conclusion: Prevention of traumatic spinal cord injury in North-east Tanzania should consider falls (particularly from height) as the leading cause, targeting male teenagers and young adults. Pressure ulcers, respiratory complications, in-hospital mortality and availability of wheelchairs should be addressed.

A biodegradable hybrid inorganic nanoscaffold for advanced stem cell therapy

Stem cell transplantation, as a promising treatment for central nervous system (CNS) diseases, has been hampered by crucial issues such as a low cell survival rate, incomplete differentiation, and limited neurite outgrowth in vivo. Addressing these hurdles, scientists have designed bioscaffolds that mimic the natural tissue microenvironment to deliver physical and soluble cues. However, several significant obstacles including burst release of drugs, insufficient cellular adhesion support, and slow scaffold degradation rate remain to be overcome before the full potential of bioscaffold-based stem-cell therapies can be realized. To this end, we developed a biodegradable nanoscaffold-based method for enhanced stem cell transplantation, differentiation, and drug delivery. These findings collectively support the therapeutic potential of our biodegradable hybrid inorganic (BHI) nanoscaffolds for advanced stem cell transplantation and neural tissue engineering.

A systematic review and quality analysis of pediatric traumatic brain injury clinical practice guidelines

BACKGROUND

Traumatic brain injuries (TBI) are a significant cause of mortality and morbidity for children globally. Adherence to evidence-based treatment guidelines have been shown to improve TBI outcomes. To inform the creation of a pediatric TBI management guideline for a low and middle income country context, we assessed the quality of available clinical practice guidelines (CPGs) for the acute management pediatric TBI.

METHODS

Articles were identified and retrieved from MEDLINE, EMBASE, Cochrane Library, LILACS, Africa-Wide Information and Global Index Medicus. These articles were screened by four reviewers independently. Based on the eligibility criteria, with the exception of literature reviews, opinion papers and editor's letters, articles published from 1995 to November 11, 2016 which covered clinical recommendations, clinical practice or treatment guidelines for the acute management of pediatric TBI (within 24 hours) were included for review. A reference and citation analysis was performed. Seven independent reviewers from low, middle and high income clinical settings with knowledge of pediatric TBI management appraised the guidelines using the AGREE II instrument. Scores for the CPGs were aggregated by domain and overall assessment was determined.

RESULTS

We screened 2372 articles of which 17 were retained for data extraction and guideline appraisal. Except for one CPG from a middle income country, the majority (16/17) of the guidelines were developed in high income countries. Seven guidelines were developed specifically for the pediatric population, while the remaining CPGs addressed the acute management of TBI in both adult and pediatric populations. The New Zealand Guideline Group (NZGG, 2006) received the highest overall assessment score of 46/49 (93.88%) followed by the Scandinavian Neurotrauma Committee (SNC, 2016) with a score of 45/49 (91.84%) followed by the Scottish Intercollegiate Guideline Network (SIGN, 2009) and Brain Trauma Foundation (BTF 2012) both with scores of 44/49 (89.80%). CPGs from Cincinnati Children's Hospital (CCH 2006) and Sao Paulo Medical School Hospital/Brazilian Society of Neurosurgery (USP/BSN, 2001) received the lowest score of 27/49 (55.10%) subsequently followed by the Appropriateness Criteria (ACR, 2015) with 29/49 (59.18%). The domains for scope and purpose and clarity of presentation received the highest scores across the CPGs, while applicability and editorial independence domains had the lowest scores with a wider variability in score range for rigor of development and stakeholder involvement.

CONCLUSIONS

To our knowledge, this is the first systematic review and guideline appraisal for pediatric CPGs concerning the acute management of TBI. Targeted guideline creation specific to the pediatric population has the potential to improve the quality of acute TBI CPGs. Furthermore, it is crucial to address the applicability of a guideline to translate the CPG from a published manuscript into clinically relevant local practice tools and for resource limited practice settings.

Risk of Motor Vehicle Collision or Driving Impairment After Traumatic Brain Injury: A Collaborative International Systematic Review and Meta-Analysis

OBJECTIVE

To synthesize knowledge of the risk of motor vehicle collision (MVC) following a traumatic brain injury (TBI) and the associated risk of driving impairment, as measured by on-road tests, computerized simulators, and self-reported or state-recorded driving records.

METHODS

Our international team searched 7 databases for studies published between 1990 and 2015 of people with TBI, controls, and data concerning either MVC or driving impairment. The included articles examined the risk of MVC among people with TBI; we excluded studies that examined the risk of having a TBI associated with being involved in an MVC.

RESULTS

From 13 578 search results, we included 8 studies involving 1663 participants with TBI and 4796 controls. We found no significant difference in the risk of MVC (odds ratio = 1.24, 95% confidence interval = 0.80-1.91, P = .34). When we restricted the analysis to self-report, the risk of MVC was higher for those without a TBI (odds ratio = 1.63, 95% confidence interval = 1.21-2.22, P = .002). In contrast, participants with TBI consistently performed worse during on-road assessments and had more problems with vehicular control.

CONCLUSION

Limitations of reviewed studies included small sample sizes, failure to specify TBI severity or time postinjury, and absence of objective measures of risk. Findings concerning the relationship between TBIs from non-MVC causes and crash risk are, therefore, inconclusive and do not provide evidence for major changes to existing clinical guidelines for driving with TBI.

Patients Who Benefit from Intracranial Pressure Monitoring without Cerebrospinal Fluid Drainage After Severe Traumatic Brain Injury

BACKGROUND

India has a high traumatic brain injury (TBI) burden and intracranial pressure monitoring (ICP) remains controversial but some patients may benefit.

OBJECTIVE

To examine the association between ICP monitor placement and outcomes, and identify Indian patients with severe TBI who benefit from ICP monitoring

METHODS

We conducted a secondary analysis of a prospective cohort study at a level 1 Indian trauma center. Patients over 18 yr with severe TBI (admission Glasgow coma scale score < 8) who received tracheal intubation for at-least 48 h were examined. Propensity-based analysis using inverse probability weighting approach was used to examine ICP monitor placement within 72 h of admission and outcomes. Outcomes were in-hospital mortality and Glasgow Outcome Scale (GOS) score at discharge, 3, 6, and 12 mo. Death, vegetative, or major impairment defined unfavorable outcome.

RESULTS

The 200 patients averaged 36 [18 to 85] yr of age and average injury severity score of 31.4 [2 to 73]. ICP monitors were placed in 126 (63%) patients. Patients with ICP monitor placement experienced lower in-hospital mortality (adjusted relative risk [aRR]; 0.50 [0.29, 0.87]) than patients without ICP monitoring. However, there was no benefit at 3, 6, and 12 mo. With ICP monitor placement, absence of cerebral edema (aRR 0.54, 95% confidence interval 0.35-0.84), and absence of intraventricular hemorrhage (aRR 0.52, 95% confidence interval 0.33-0.82) were associated with reduced unfavorable outcomes.

CONCLUSION

ICP monitor placement without cerebrospinal fluid drainage within 72 h of admission was associated with reduced in-patient mortality. Patients with severe TBI but without cerebral edema and without intraventricular hemorrhage may benefit from ICP monitoring.

HAX1 is associated with neuronal apoptosis and astrocyte proliferation after spinal cord injury

HS1-associated protein X-1 (HAX1) is a class of multifunctional protein, participated in various physiological processes such as cell apoptosis, proliferation and motility. However, the HAX1 expression and function in the spinal cord injury (SCI) pathological process have not been investigated. In our current research, the rat model of SCI was established, and then we explored the possible role of HAX1 after SCI. The results of western blot indicated that HAX1 was present in sham operated control group and significantly elevated at 3 days post SCI, then declined gradually. Immunohistochemical studies indicated HAX1 expression was enhanced significantly in white and gray matter at 3 days post SCI compared with sham operated group. Double immunofluorescence staining showed the proportion of cells, double-labeled HAX1 and neurons, astrocytes, increased significantly at 3 days post SCI. In addition, co-localization of HAX1/active caspase-3 and HAX1/PCNA was tested in cells. Furthermore, over-expression of HAX1 inhibited neuronal apoptosis in vitro, and in astrocytes HAX1 silencing could down-regulate PCNA expression post LPS treatment. Meanwhile, CCK8 assay showed that knockdown of HAX1 could inhibit the astrocyte proliferation. In summary, our data indicated that HAX1 might play significant roles in pathological process of neuronal apoptosis and astrocyte proliferation during SCI.

Characterization of 95 patients with traumatic brain injury due to gunshot wounds at a referral center in Cali, Colombia

OBJECTIVE

This study aims to describe cases of traumatic brain injury due to gunshot wounds in civilian population over 18 years of age, treated at a referral hospital in Cali, Colombia and compare the clinical outcomes at discharge.

METHODS

An observational, descriptive cross-sectional study was conducted by retrospectively collecting clinical data related to adult patients that presented traumatic brain injury due to civil gunshot-wounds and that consulted to the emergency room at Fundación Valle del Lili Hospital in Cali, Colombia between January 2010 and February of 2016. A univariate analysis was performed to determine factors associated with death and adverse clinical outcomes.

RESULTS

A total of 95 patients older than 18 years, with traumatic brain injury by gunshot were included in the civil context. The 91.6% were male. The main context was interpersonal violence with 54.7%. The most common method of transportation was by ambulance (79%). The Glasgow score at admission was 3-8 in 64.2% of cases; 9-12 in 6.32% and 13-15 in 28.4%. On admission, head CT scan was performed in 82 (86.3%) patients within the first hour, finding a Marshall-Score between I-III in 60.9%, of IV in 17.8% of cases and a score between V-VI and in 4.1%. The trajectory was non-transfixing penetrating in 43.2%, transfixing in 27.3% and tangential in 9.5%. Mortality was 45.3% in total, 39% died within the first 24hours.

CONCLUSIONS

A major compromise on admission determines an overall poorer prognosis and a high likelihood of death in the first 24-hours.

Cranioplasty with a low-cost customized polymethylmethacrylate implant using a desktop 3D printer

OBJECTIVE

Cranioplasty implants should be widely available, low in cost, and customized or easy to mold during surgery. Although autologous bone remains the first choice for repair, it cannot always be used due to infection, fragmentation, bone resorption, or other causes, which led to use of synthetic alternatives. The most frequently used allogenic material for cranial reconstructions with long-term results is polymethylmethacrylate (PMMA). Three-dimensional printing technology has allowed the production of increasingly popular customized, prefabricated implants. The authors describe their method and experience with a customized PMMA prosthesis using a precise and reliable low-cost implant that can be customized at any institution with open-source or low-cost software and desktop 3D printers.

METHODS

A review of 22 consecutive patients undergoing CT-based, low-cost, customized PMMA cranioplasty over a 1-year period at a university teaching hospital was performed. Preoperative data included patient sex and age; CT modeling parameters, including the surface area of the implant (defect); reason for craniectomy; date(s) of injury and/or resections; the complexity of the defect; and associated comorbidities. Postoperative data included morbiditiy and complications, such as implant exposure, infection, hematoma, seroma, implant failure, and seizures; the cost of the implant; and cosmetic outcome.

RESULTS

Indications for the primary craniectomy were traumatic brain injury (16, 73%), tumor resection (3, 14%), infection (1, 4%), and vascular (2, 9%). The median interval between previous surgery and PMMA cranioplasty was 12 months. The operation time ranged from 90 to 150 minutes (mean 126 minutes). The average cranial defect measured 65.16 cm2 (range 29.31-131.06 cm2). During the recovery period, there was no sign of infection, implant rejection, or wound dehiscence, and none of the implants had to be removed over a follow-up ranging from 1 to 6 months. The aesthetic appearance of all patients was significantly improved, and the implant fit was excellent.

CONCLUSIONS

The use of a customized PMMA was associated with excellent patient, family, and surgeon satisfaction at follow-up at a fraction of the cost associated with commercially available implants. This technique could be an attractive option to all patients undergoing cranioplasty.

Adenosine, lidocaine, and Mg2+ (ALM) resuscitation fluid protects against experimental traumatic brain injury

BACKGROUND

Currently, no drug therapy prevents secondary injury progression after traumatic brain injury (TBI). Our aim was to investigate the effects of small-volume intravenous adenosine, lidocaine, and Mg (ALM) resuscitation fluid after moderate TBI in a rat fluid-percussion injury model.

METHODS

Anesthetized, mechanically ventilated male Sprague-Dawley rats (449 ± 5 g) were randomly assigned to one of four groups: (1) sham (craniotomy without TBI), (2) no-treatment, (3) saline-control, or (4) ALM therapy groups (all n = 16). A subdural probe was implanted in eight animals per group to measure cerebral blood flow. Fifteen minutes after moderate TBI was induced with lateral fluid percussion injury (2.57 atm), a single 3% NaCl ± ALM bolus (0.7 mL/kg) was injected intravenously, and after 60 minutes (Phase 1), 0.9% NaCl ± ALM stabilization "drip" (0.5 mL/kg per hour) was administered for 3 hours (Phase 2).

RESULTS

Mortality (without subdural brain probe) was 25% (saline controls) and 0% (ALM). Sixty minutes after bolus, ALM significantly increased cardiac function, cortical blood flow (CBF; approximately threefold) and blunted systemic inflammation compared to saline controls. Three hours after infusion drip, ALM improved left ventricular function, supported higher CBF, decreased proinflammatory cytokines systemically (IL-1β, tumor necrosis factor α, and regulated on activation, normal T cell expressed and secreted [RANTES]), increased anti-inflammatory cytokines in brain tissue (IL-10, IL-4), lowered brain injury markers (neuron-specific enolase, Syndecan-1, HMGB-1), reduced coagulopathy, increased platelet aggregation, and maintained baseline fibrinogen levels. Saline-controls were proinflammatory (brain, heart, lung, and blood) and hypocoagulable with neurogenic enlargement of the right side of the heart. Survival time significantly correlated with plasma neuron-specific enolase (p = 0.001) and CBF at 180 minutes (p = 0.009), and CBF correlated with brain anti-inflammatory cytokines (p = 0.001-0.034).

CONCLUSION

After moderate TBI, ALM resuscitation fluid increased survival and protected against early secondary injury by reducing coagulopathy, inflammation, and platelet dysfunction.

Assessment of Rehabilitation Infrastructure in Peru

OBJECTIVE

To assess rehabilitation infrastructure in Peru in terms of the World Health Organization (WHO) health systems building blocks.

DESIGN

Anonymous quantitative survey; questions were based on the WHO's Guidelines for Essential Trauma Care and rehabilitation professionals' input.

SETTING

Large public hospitals and referral centers and an online survey platform.

PARTICIPANTS

Convenience sample of hospital personnel working in rehabilitation and neurology (N=239), recruited through existing contacts and professional societies.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Outcome measures were for 4 WHO domains: health workforce, health service delivery, essential medical products and technologies, and health information systems.

RESULTS

Regarding the domain of health workforce, 47% of physical therapists, 50% of occupational therapists, and 22% of physiatrists never see inpatients. Few reported rehabilitative nurses (15%) or prosthetist/orthotists (14%) at their hospitals. Even at the largest hospitals, most reported ≤3 occupational therapists (54%) and speech-language pathologists (70%). At hospitals without speech-language pathologists, physical therapists (49%) or nobody (34%) perform speech-language pathology roles. At hospitals without occupational therapists, physical therapists most commonly (59%) perform occupational therapy tasks. Alternate prosthetist/orthotist task performers are occupational therapists (26%), physical therapists (19%), and physicians (16%). Forty-four percent reported interdisciplinary collaboration. Regarding the domain of health services, the most frequent inpatient and outpatient rehabilitation barriers were referral delays (50%) and distance/transportation (39%), respectively. Regarding the domain of health information systems, 28% reported rehabilitation service data collection. Regarding the domain of essential medical products and technologies, electrophysical agents (88%), gyms (81%), and electromyography (76%) were most common; thickened liquids (19%), swallow studies (24%), and cognitive training tools (28%) were least frequent.

CONCLUSIONS

Rehabilitation emphasis is on outpatient services, and there are comparatively adequate numbers of physical therapists and physiatrists relative to rehabilitation personnel. Financial barriers seem low for accessing existing services. There appear to be shortages of inpatient rehabilitation, specialized services, and interdisciplinary collaboration. These may be addressed by redistributing personnel and investing in education and equipment for specialized services. Further examination of task sharing's role in Peru's rehabilitation services is necessary to evaluate its potential to address deficiencies.

The Growth of Neurosurgery in East Africa: Challenges

As the second of 3 articles in this series, the aim of this article is to provide readers with an understanding of the development of neurosurgery in East Africa (foundations), the challenges that arise in providing neurosurgical care in developing countries (challenges), and an overview of traditional and novel approaches to overcoming these challenges and improving health care in the region (innovations). Recognizing the challenges that need to be addressed is the first step to implementing efficient and qualified surgery delivery systems in low- and middle-income countries. We reviewed the major challenges facing health care in East Africa and grouped them into 5 categories: 1) burden of surgical disease and workforce crisis; 2) global health view of surgery as "the neglected stepchild"; 3) need for recognizing the surgical system as an interdependent network and importance of organizational and equipment deficits; 4) lack of education in the community, failure of primary care systems, and net result of overwhelming tertiary care systems; 5) personal and professional burnout as well as brain drain of promising human resources from low- and middle-income countries in East Africa and similar regions across the world. Each major challenge was detailed and analyzed by authors who have worked or are currently working in the region, providing a personal perspective.

hucMSC derived exosomes promote functional recovery in spinal cord injury mice via attenuating inflammation

The exploration of effective spinal cord injury (SCI) healing still remain a great challenge due to the high morbidity, complex pathology and unclear targets. Human umbilical cord mesenchymal stem cells (hucMSC) play an important role in tissue regeneration. However, transplanting stem cells has a potential risk of teratogenicity. Recent studies have suggested that exosomes secreted by stem cells may contribute to tissue injury repair. We hypothesized that the application of hucMSC derived exosomes may be a potential way for SCI treatment. Our studies showed the hucMSC derived exosomes with a mean particle size of 70 nm could effectively trigger the bone marrow derived macrophage (BMDM) polarization from M1 to a M2 phenotype. In vivo studies demonstrated that the hucMSC derived exosomes could improve the functional recovery after SCI through down-regulation of the inflammatory cytokines, such as TNF-α, MIP-1α, IL-6 and IFN-γ. Collectively, our findings indicated that hucMSC derived exosomes could facilitate spinal cord injury healing via attenuating the inflammation of the injury region. Our results provided a new perspective and therapeutic strategy for the use of hucMSC derived exosomes in soft tissue repair.

Neuroprotective Effects of Platonin, a Therapeutic Immunomodulating Medicine, on Traumatic Brain Injury in Mice after Controlled Cortical Impact

Traumatic brain injury (TBI) is one of the leading causes of mortality worldwide and leads to persistent cognitive, sensory, motor dysfunction, and emotional disorders. TBI-caused primary injury results in structural damage to brain tissues. Following the primary injury, secondary injuries which are accompanied by neuroinflammation, microglial activation, and additional cell death subsequently occur. Platonin, a cyanine photosensitizing dye, has been used to treat trauma, ulcers, and some types of acute inflammation. In the present study, the neuroprotective effects of platonin against TBI were explored in a controlled cortical impact (CCI) injury model in mice. Treatment with platonin (200 µg/kg) significantly reduced the neurological severity score, general locomotor activity, and anxiety-related behavior, and improved the rotarod performance of CCI-injured mice. In addition, platonin reduced lesion volumes, the expression of cleaved caspase-3, and microglial activation in TBI-insulted brains. Platonin also suppressed messenger (m)RNA levels of caspase-3, caspase-1, cyclooxygenase-2, tumor necrosis factor-α, interleukin-6, and interleukin-1β. On the other hand, free radical production after TBI was obviously attenuated in platonin-treated mice. Treatment with platonin exhibited prominent neuroprotective properties against TBI in a CCI mouse model through its anti-inflammatory, anti-apoptotic, and anti-free radical capabilities. This evidence collectively indicates that platonin may be a potential therapeutic medicine for use with TBIs.

NaHS restores mitochondrial function and inhibits autophagy by activating the PI3K/Akt/mTOR signalling pathway to improve functional recovery after traumatic brain injury

Traumatic brain injury (TBI) is one of the most serious public health problems in the world. TBI causes neurological deficits by triggering secondary injuries. Hydrogen sulfide (H₂S), a gaseous mediator, has been reported to exert neuroprotective effects in central nervous system diseases, such as TBI. However, the molecular mechanisms involved in this effect are still unclear. The present study was designed to explore the ability of NaHS, a H₂S donor, to provide neuroprotection in a mouse model of TBI and to discover the associated molecular mechanisms of these protective effects. Here, we found that administration of NaHS not only maintained the integrity of the blood brain barrier (BBB), protected neurons from apoptosis, and promoted remyelination and axonal reparation but also protected mitochondrial function. In addition, we found that autophagy was inhibited after treatment with NaHS following TBI, an effect that was induced by activation of the PI3K/AKT/mTOR signalling pathway. Our study indicated that H₂S treatment is beneficial for TBI, pointing to H₂S as a potential therapeutic target for treating TBI.

Thioredoxin-Interacting Protein (TXNIP) in Cerebrovascular and Neurodegenerative Diseases: Regulation and Implication

Neurological diseases, including acute attacks (e.g., ischemic stroke) and chronic neurodegenerative diseases (e.g., Alzheimer's disease), have always been one of the leading cause of morbidity and mortality worldwide. These debilitating diseases represent an enormous disease burden, not only in terms of health suffering but also in economic costs. Although the clinical presentations differ for these diseases, a growing body of evidence suggests that oxidative stress and inflammatory responses in brain tissue significantly contribute to their pathology. However, therapies attempting to prevent oxidative damage or inhibiting inflammation have shown little success. Identification and targeting endogenous "upstream" mediators that normalize such processes will lead to improve therapeutic strategy of these diseases. Thioredoxin-interacting protein (TXNIP) is an endogenous inhibitor of the thioredoxin (TRX) system, a major cellular thiol-reducing and antioxidant system. TXNIP regulating redox/glucose-induced stress and inflammation, now is known to get upregulated in stroke and other brain diseases, and represents a promising therapeutic target. In particular, there is growing evidence that glucose strongly induces TXNIP in multiple cell types, suggesting possible physiological roles of TXNIP in glucose metabolism. Recently, a significant body of literature has supported an essential role of TXNIP in the activation of the NOD-like receptor protein (NLRP3)-inflammasome, a well-established multi-molecular protein complex and a pivotal mediator of sterile inflammation. Accordingly, TXNIP has been postulated to reside centrally in detecting cellular damage and mediating inflammatory responses to tissue injury. The majority of recent studies have shown that pharmacological inhibition or genetic deletion of TXNIP is neuroprotective and able to reduce detrimental aspects of pathology following cerebrovascular and neurodegenerative diseases. Conspicuously, the mainstream of the emerging evidences is highlighting TXNIP link to damaging signals in endothelial cells. Thereby, here, we keep the trend to present the accumulative data on CNS diseases dealing with vascular integrity. This review aims to summarize evidence supporting the significant contribution of regulatory mechanisms of TXNIP with the development of brain diseases, explore pharmacological strategies of targeting TXNIP, and outline obstacles to be considered for efficient clinical translation.

γδ T cells provide the early source of IFN-γ to aggravate lesions in spinal cord injury

Immune responses and neuroinflammation are critically involved in spinal cord injury (SCI). γδ T cells, a small subset of T cells, regulate the inflammation process in many diseases, yet their function in SCI is still poorly understood. In this paper, we demonstrate that mice deficient in γδ T cells (TCRδ^-/- ) showed improved functional recovery after SCI. γδ T cells are detected at the lesion sites within 24 hours after injury and are predominantly of the Vγ4 subtype and express the inflammatory cytokine IFN-γ. Inactivating IFN-γ signaling in macrophages results in a significantly reduced production of proinflammatory cytokines in the cerebrospinal fluid (CSF) of mice with SCIs and improves functional recovery. Furthermore, treatment of SCI with anti-Vγ4 antibodies has a beneficial effect, similar to that obtained with anti-TNF-α. In SCI patients, γδ T cells are detected in the CSF, and most of them are IFN-γ positive. In conclusion, manipulation of γδ T cell functions may be a potential approach for future SCI treatment.

Language and style: A barrier to neurosurgical research and advancement in Latin America

Background:

The neurosurgical burden in Latin America is understudied and likely underestimated, thus it is imperative to improve quality, training, and delivery of neurosurgical care. A significant aspect of this endeavor is for Latin America to become an integral aspect of the global neurosurgical community, however, there is a paucity of ideology and literature coming from Central and South America. We sought to explore neurosurgical dialogue originating from Latin America as well as barriers to the advancement of neurosurgery in this region.

Methods:

We conducted a systematic literature review exploring research originating in Latin America in three international neurosurgical journals – Journal of Neurosurgery, Surgical Neurology International, and World Neurosurgery. We utilized PubMed search algorithms to identify articles. Inclusion criteria included publication within the three aforementioned journals, author affiliation with Latin American institutions, and publication within the specified time frame of January 2014 to July 2017.

Results:

There were 7469 articles identified that met the search criteria. Of these 7469 articles, 326 (4.4%) were from Latin American nations.

Conclusion:

Our data suggests a relatively low percentage of neurosurgical research originating from Latin America, suggesting a significant lack of participation in the global neurosurgical community. Barriers to global scientific communication include language, rhetorical style, culture, history, biases, funding, and governmental support. Despite challenges, Latin America is making strides towards improvement including the development of neurosurgical societies, as well as international collaborative training and research programs. We consider our report to be a valid initiation of discussion of the broader issue of neurosurgical communication.

A cellular spinal cord scaffold seeded with rat adipose‑derived stem cells facilitates functional recovery via enhancing axon regeneration in spinal cord injured rats

Spinal cord injury (SCI), usually resulting in severe sensory and motor deficits, is a major public health concern. Adipose-derived stem cells (ADSCs), one type of adult stem cell, are free from ethical restriction, easily isolated and enriched. Therefore, ADSCs may provide a feasible cell source for cell-based therapies in treatment of SCI. The present study successfully isolated rat ADSCs (rADSCs) from Sprague-Dawley male rats and co-cultured them with acellular spinal cord scaffolds (ASCs). Then, a rat spinal cord hemisection model was built and rats were randomly divided into 3 groups: SCI only, ASC only, and ASC + ADSCs. Furthermore, behavioral tests were conducted to evaluate functional recovery. Hematoxylin & Eosin staining and immunofluorence were carried out to assess histopathological remodeling. In addition, biotinylated dextran amines anterograde tracing was employed to visualize axon regeneration. The data demonstrated that harvested cells, which were positive for cell surface antigen cluster of differentiation (CD) 29, CD44 and CD90 and negative for CD4, detected by flow cytometry analysis, held the potential to differentiate into osteocytes and adipocytes. Rats that received transplantation of ASCs seeded with rADSCs benefited greatly in functional recovery through facilitation of histopathological rehabilitation, axon regeneration and reduction of reactive gliosis. rADSCs co-cultured with ASCs may survive and integrate into the host spinal cord on day 14 post-SCI.

Current Opportunities for Clinical Monitoring of Axonal Pathology in Traumatic Brain Injury

Traumatic brain injury (TBI) is a multidimensional and highly complex disease commonly resulting in widespread injury to axons, due to rapid inertial acceleration/deceleration forces transmitted to the brain during impact. Axonal injury leads to brain network dysfunction, significantly contributing to cognitive and functional impairments frequently observed in TBI survivors. Diffuse axonal injury (DAI) is a clinical entity suggested by impaired level of consciousness and coma on clinical examination and characterized by widespread injury to the hemispheric white matter tracts, the corpus callosum and the brain stem. The clinical course of DAI is commonly unpredictable and it remains a challenging entity with limited therapeutic options, to date. Although axonal integrity may be disrupted at impact, the majority of axonal pathology evolves over time, resulting from delayed activation of complex intracellular biochemical cascades. Activation of these secondary biochemical pathways may lead to axonal transection, named secondary axotomy, and be responsible for the clinical decline of DAI patients. Advances in the neurocritical care of TBI patients have been achieved by refinements in multimodality monitoring for prevention and early detection of secondary injury factors, which can be applied also to DAI. There is an emerging role for biomarkers in blood, cerebrospinal fluid, and interstitial fluid using microdialysis in the evaluation of axonal injury in TBI. These biomarker studies have assessed various axonal and neuroglial markers as well as inflammatory mediators, such as cytokines and chemokines. Moreover, modern neuroimaging can detect subtle or overt DAI/white matter changes in diffuse TBI patients across all injury severities using magnetic resonance spectroscopy, diffusion tensor imaging, and positron emission tomography. Importantly, serial neuroimaging studies provide evidence for evolving axonal injury. Since axonal injury may be a key risk factor for neurodegeneration and dementias at long-term following TBI, the secondary injury processes may require prolonged monitoring. The aim of the present review is to summarize the clinical short- and long-term monitoring possibilities of axonal injury in TBI. Increased knowledge of the underlying pathophysiology achieved by advanced clinical monitoring raises hope for the development of novel treatment strategies for axonal injury in TBI.

What intracranial pathologies are most likely to receive intervention? A preliminary study on referrals from an emergency centre with no on-site neurosurgical capabilities

Introduction

Access to neurosurgical facilities remains limited in resource-restricted medical environments worldwide, including Africa. Many hospitals refer patients to off-site facilities if they require intervention. Unnecessary referrals, however, can be detrimental to the patient and/or costly to the healthcare system itself. The aim of this study was to determine the frequency and associated intracranial pathology of patients who did and did not receive active neurosurgical intervention after having presented to an academic emergency centre at a hospital without on-site neurosurgical capabilities.

Methods

A one-year, retrospective record review of all patients who presented with potential neurosurgical pathology to a tertiary academic emergency centre in Johannesburg, South Africa was conducted.

Results

A total of 983 patients received a computed tomography brain scan for suspected neurosurgical pathology. There were 395 positive scans; 67.8% with traumatic brain injury (TBI) and 32.3% non-traumatic brain injury (non-TBI). Only 14.4% of patients received neurosurgical intervention, mostly non-TBI-related. The main intervention was a craniotomy for both TBI and non-TBI patients. The main TBI haemorrhages that received an intervention were subdural (SDH) (16.5%) and extradural (10.4%) haemorrhages. More than half the patients with non-TBI SDHs as well as those with aneurysms and subarachnoid haemorrhages received an intervention.

Discussion

Based on this study’s findings, in a resource-restricted setting, the patients who should receive preference for neurosurgical referral and intervention are (1) those with intracranial haemorrhages (2) those with non-traumatic SDH more than traumatic SDH and (3) those patients with non-traumatic subarachnoid haemorrhages caused by aneurysms.

Mortality due to traumatic spinal cord injuries in Europe: a cross-sectional and pooled analysis of population-wide data from 22 countries

BACKGROUND

Traumatic spinal cord injuries (TSCI) pose a significant burden globally, while existing epidemiological data-especially on population mortality-are limited. The aim of this study was to calculate the age-standardized population mortality rates attributable to TSCI in 22 European countries, along with the pooled age-standardized mortality rate attributable to TSCI in Europe.

METHODS

A descriptive cross-sectional epidemiological study was conducted. Crude and age-standardized mortality rates attributable to TSCI for the year 2012 for 22 European countries were compared using data from death certificates provided by Eurostat. Pooled age-standardized mortality rates were calculated using the random effects model, and overall number of cases were estimated by extrapolating our findings to the populations of EU and Europe (48 countries), in 2012.

RESULTS

A total of 1840 TSCI-related deaths were identified, of which 1084 (59%) were males. The pooled age-standardized TSCI-related mortality rate of 6.7 per million (95% CI: 5.2 to 8.2) overall, 9.4 (95% CI: 7.3 to 11.5) for males, and 4.5 (95% CI: 3.4 to 5.6) for females. Extrapolating our results, 3152 (95% CI: 2441 to 3915) deaths would occur in 2012 in the EU-28 and 4570 (95% CI: 3538 to 5675) deaths in the whole Europe. TSCI-related deaths contributed by 2% (95% CI: 1.8% to 2.2%) to the overall injury related mortality. 61% of fatal TSCI were located in the cervical spine area.

CONCLUSION

To our knowledge, this is the largest study that reports TSCI-related population-based mortalities to date which brings valuable information that can inform further research or prevention strategies. Our study presents a comprehensive and large-scale overview of TSCI-related population mortality in Europe. With an estimated toll of nearly five thousand lives that could be potentially saved by prevention, our findings confirm TSCI as an important cause of injury related deaths in Europe. Further action towards harmonization of case ascertainment and towards prevention strategies targeted mainly on the elderly is warranted.

Years of life lost due to traumatic brain injury in Europe: A cross-sectional analysis of 16 countries

INTRODUCTION

Traumatic brain injuries (TBIs) are a major public health, medical, and societal challenge globally. They present a substantial burden to victims, their families, and the society as a whole. Although indicators such as incidence or death rates provide insight into the occurrence and outcome of TBIs in various populations, they fail to quantify the full extent of their public health and societal impact. Measures such as years of life lost (YLLs), which quantifies the number of years of life lost because the person dies prematurely due to a disease or injury, should be employed to better quantify the population impact. The aim of this study was to provide an in-depth analysis of the burden of deaths due to TBI by calculating TBI-specific YLLs in 16 European countries, analyzing their main causes and demographic patterns, using data extracted from death certificates under unified guidelines and collected in a standardized manner.

METHODS AND FINDINGS

A population-wide, cross-sectional epidemiological study was conducted in 16 European countries to estimate TBI YLLs for the year 2013. The data used for all analyses in this study were acquired from the statistical office of the European Union (Eurostat). A specifically tailored dataset of micro-level data was provided that listed the external cause of death (International Classification of Diseases-10th Revision [ICD-10] codes V01-Y98), the specific nature of injury (ICD-10 codes S00-T98), the age at death, and sex for each death. Overall number of TBI YLLs, crude and age-standardized TBI YLL rates, and TBI YLLs per case were calculated stratified for country, sex, and age. Pooled analyses were performed in order to estimate summary age-standardized rates of TBI YLLs. In order to evaluate the relative importance of TBI in the context of all injuries, proportions of TBI YLLs out of overall injury YLLs were calculated. The total number of TBI YLLs was estimated by extrapolating the pooled crude rate of TBI YLLs in the 16 analyzed countries to the total population of the 28 member states of the EU (EU-28). We found that a total of 17,049 TBI deaths occurred in 2013 in the 16 analyzed countries. These translated into a total of 374,636 YLLs. The pooled age-standardized rate of YLLs per 100,000 people per year was 259.1 (95% CI: 205.8 to 312.3) overall, 427.5 (95% CI: 290.0 to 564.9) in males, and 105.4 (95% CI: 89.1 to 121.6) in females. Males contributed substantially more to TBI YLLs than females (282,870 YLLs, 76% of all TBI YLLs), which translated into a rate ratio of 3.24 (95% CI: 3.22 to 3.27). Each TBI death was on average associated with 24.3 (95% CI: 22.0 to 26.6) YLLs overall, 25.6 (95% CI: 23.4 to 27.8) in males and 20.9 (17.9 to 24.0) in females. Falls and traffic crashes were the most common external causes of TBI YLLs. TBI contributed on average 41% (44% in males and 34% in females) to overall injury YLLs. Extrapolating our findings, about 1.3 million YLLs were attributable to TBI in the EU-28 in 2013 overall, 1.1 million in males and 271,000 in females. This study is based on administratively collected data from 16 countries, and despite the efforts to harmonize them to the greatest possible extent, there may be differences in coding practices or reporting between countries. If present, these would be inherited into our findings without our ability to control for them. The extrapolation of the pooled rates from the 16 countries to the EU-28 should be interpreted with caution.

CONCLUSIONS

Our study showed that TBI-related deaths and YLLs have a substantial impact at the individual and population level in Europe and present an important societal and economic burden that must not be overlooked. We provide information valuable for policy-makers, enabling them to evaluate and plan preventive activities and resource allocation, and to formulate and implement strategic decisions. In addition, our results can serve as a basis for analyzing the overall burden of TBI in the population.

The Traumatic Brain Injury Endpoints Development (TED) Initiative: Progress on a Public-Private Regulatory Collaboration To Accelerate Diagnosis and Treatment of Traumatic Brain Injury

The Traumatic Brain Injury Endpoints Development (TED) Initiative is a 5-year, Department of Defense-funded project that is working toward the ultimate goal of developing better designed clinical trials, leading to more precise diagnosis, and effective treatments for traumatic brain injury (TBI). TED is comprised of leading academic clinician-scientists, along with innovative industry leaders in biotechnology and imaging technology, patient advocacy organizations, and philanthropists, working collaboratively with regulatory authorities, specifically the U.S. Food and Drug Administration (FDA). The goals of the TED Initiative are to gain consensus and validation of TBI clinical outcome assessment measures and biomarkers for endorsement by global regulatory agencies for use in drug and device development processes. This article summarizes the Initiative's Stage I progress over the first 18 months, including intensive engagement with a number of FDA divisions responsible for review and validation of biomarkers and clinical outcome assessments, progression into the prequalification phase of the FDA's Medical Device Development Tool program for a candidate set of neuroimaging biomarkers, and receipt of the FDA's Recognition of Research Importance Letter and a Letter of Support regarding TBI. Other signal achievements relate to the creation of the TED Metadataset, harmonizing study measures across eight major TBI studies, and the leadership role played by TED investigators in the conversion of the NINDS TBI Common Data Elements to Clinical Data Interchange Standards Consortium standards. This article frames both the near-term expectations and the Initiative's long-term vision to accelerate approval of treatments for patients affected by TBI in urgent need of effective therapies.

Methylprednisolone Administration Following Spinal Cord Injury Reduces Aquaporin 4 Expression and Exacerbates Edema

Spinal cord injury (SCI) is an incapacitating condition that affects motor, sensory, and autonomic functions. Since 1990, the only treatment administered in the acute phase of SCI has been methylprednisolone (MP), a synthetic corticosteroid that has anti-inflammatory effects; however, its efficacy remains controversial. Although MP has been thought to help in the resolution of edema, there are no scientific grounds to support this assertion. Aquaporin 4 (AQP4), the most abundant component of water channels in the CNS, participates in the formation and elimination of edema, but it is not clear whether the modulation of AQP4 expression by MP plays any role in the physiopathology of SCI. We studied the functional expression of AQP4 modulated by MP following SCI in an experimental model in rats along with the associated changes in the permeability of the blood-spinal cord barrier. We analyzed these effects in male and female rats and found that SCI increased AQP4 expression in the spinal cord white matter and that MP diminished such increase to baseline levels. Moreover, MP increased the extravasation of plasma components after SCI and enhanced tissue swelling and edema. Our results lend scientific support to the increasing motion to avoid MP treatment after SCI.

Development of a systems-based in situ multiplex biomarker screening approach for the assessment of immunopathology and neural tissue plasticity in male rats after traumatic brain injury

Traumatic brain injuries (TBIs) pose a massive burden of disease and continue to be a leading cause of morbidity and mortality throughout the world. A major obstacle in developing effective treatments is the lack of comprehensive understanding of the underlying mechanisms that mediate tissue damage and recovery after TBI. As such, our work aims to highlight the development of a novel experimental platform capable of fully characterizing the underlying pathobiology that unfolds after TBI. This platform encompasses an empirically optimized multiplex immunohistochemistry staining and imaging system customized to screen for a myriad of biomarkers required to comprehensively evaluate the extent of neuroinflammation, neural tissue damage, and repair in response to TBI. Herein, we demonstrate that our multiplex biomarker screening platform is capable of evaluating changes in both the topographical location and functional states of resident and infiltrating cell types that play a role in neuropathology after controlled cortical impact injury to the brain in male Sprague-Dawley rats. Our results demonstrate that our multiplex biomarker screening platform lays the groundwork for the comprehensive characterization of changes that occur within the brain after TBI. Such work may ultimately lead to the understanding of the governing pathobiology of TBI, thereby fostering the development of novel therapeutic interventions tailored to produce optimal tissue protection, repair, and/or regeneration with minimal side effects, and may ultimately find utility in a wide variety of other neurological injuries, diseases, and disorders that share components of TBI pathobiology.

Assistive technology to enable sleep function in patients with acquired brain injury: Issues and opportunities

Introduction

Sleep disorders in patients with acquired brain injury are highly burdensome and associated with disability. An assistive technology framework emphasises the need to develop and apply a broad range of devices, strategies, and practices to ameliorate disabilities. We aimed to summarise scientific evidence regarding the utility of assistive technology in managing sleep disorders in patients with various causes of acquired brain injury.

Method

We retrieved articles before January 2016, through database searches of Medline, Embase, PsycINFO, CINAHL, and various bibliographies. The person–environment–occupation framework was used to analyse complex data pertaining to technology application and utility.

Results

We found 21 studies that described seven assistive technologies (continuous positive airway pressure, adaptive servo ventilator, nasotracheal suction mechanical ventilation, positioning devices, cognitive behavioural therapy, light therapy, and acupuncture) utilised in patients with acquired brain injury to manage sleep disorders.

Conclusion

Assistive technologies demonstrated effectiveness in alleviating and/or managing sleep disorders after acquired brain injury. Adherence to using the technology is limited by the level of injury-induced cognitive and physical impairment, technological regime, and environmental support. Development of user-friendly sleep-assistive technologies that take into consideration functional limitations and practice guidelines on structural communication between the occupational therapist, patient, and caregiver may facilitate patients’ self-determination in managing sleep disorders.