Reliability of S100B in predicting severity of central nervous system injury

Cognitive-Enhancing Effect of Marine Brown Algae-Derived Phenolics through S100B Inhibition and Antioxidant Activity in the Rat Model of Ischemic Stroke

Cognitive impairments are frequently reported after ischemic strokes. Novel and effective treatments are required. This study aimed to develop a functional ingredient obtained from marine algae and to determine the effect of the extract on antioxidative stress, as well as neuroprotective effects, in a rat model of MCAO-induced ischemic stroke. Among the selected marine algal extracts, Sargassum polycystum displayed the highest total phenolic content and antioxidative potential, and was subsequently used to evaluate cognitive function in rat models of ischemic stroke. The S. polycystum extract, administered at doses of 100, 300, and 500 mg/kg BW, significantly improved cognitive function by enhancing cognitive performance in the Morris water maze and novel object recognition tests. Biochemical changes revealed that providing S. polycystum increased the activities of SOD, CAT, and GSH-Px by 52.48%, 50.77%, and 66.20%, respectively, and decreased the concentrations of MDA by 51.58% and S100B by 36.64% compared to the vehicle group. These findings suggest that S. polycystum extract may mitigate cognitive impairment in ischemic stroke by reducing oxidative stress and inhibiting S100B expression, thus highlighting its potential as a functional ingredient for drugs and nutraceuticals aimed at neuroprotection.

Sepsis Biomarkers: Advancements and Clinical Applications-A Narrative Review

Sepsis is now defined as a life-threatening syndrome of organ dysfunction triggered by a dysregulated host response to infection, posing significant challenges in critical care. The main objective of this review is to evaluate the potential of emerging biomarkers for early diagnosis and accurate prognosis in sepsis management, which are pivotal for enhancing patient outcomes. Despite advances in supportive care, traditional biomarkers like C-reactive protein and procalcitonin have limitations, and recent studies have identified novel biomarkers with increased sensitivity and specificity, including circular RNAs, HOXA distal transcript antisense RNA, microRNA-486-5p, protein C, triiodothyronine, and prokineticin 2. These emerging biomarkers hold promising potential for the early detection and prognostication of sepsis. They play a crucial role not only in diagnosis but also in guiding antibiotic therapy and evaluating treatment effectiveness. The introduction of point-of-care testing technologies has brought about a paradigm shift in biomarker application, enabling swift and real-time patient evaluation. Despite these advancements, challenges persist, notably concerning biomarker variability and the lack of standardized thresholds. This review summarizes the latest advancements in sepsis biomarker research, spotlighting the progress and clinical implications. It emphasizes the significance of multi-biomarker strategies and the feasibility of personalized medicine in sepsis management. Further verification of biomarkers on a large scale and their integration into clinical practice are advocated to maximize their efficacy in future sepsis treatment.

The Role of S100b Protein Biomarker in Brain Death: A Literature Review

Brain death (BD) represents the irreversible loss of all brain functions, including the brainstem, and is equivalent to clinical death established by neurological criteria. However, clinical diagnosis, mainly based on the absence of primary reflexes post-acute brain injury, remains a challenge in hospital settings. The S100 calcium-binding protein beta (S100b) is used to monitor brain injuries, as recommended by neurotrauma care guidelines in some countries. Its levels are associated with severity and mortality, particularly after traumatic brain injury (TBI) and cerebral hemorrhage. The evaluation of S100b levels in investigating brain death is promising; however, aspects such as cutoff values remain to be elucidated. This paper reviews the literature on the use of S100b as a biomarker in diagnosing brain death. It is noteworthy that there is still no defined cutoff for S100b levels in confirming brain death. Additionally, when considering the use of S100b in emergency situations, a point-of-care methodology should be established to support clinical decision-making quickly and easily in the early identification of patients who are more likely to progress to brain death. In this context, S100b levels may assist in establishing the diagnosis of brain death, complementing existing clinical evidence. This, in turn, can optimize and qualify the organ donation process, reducing costs with ineffective therapies and minimizing the suffering of the families involved.

Innovative in vivo rat model for global cerebral hypoxia: a new approach to investigate therapeutic and preventive drugs

Introduction: Severe acute global cerebral hypoxia can lead to significant disability in humans. Although different animal models have been described to study hypoxia, there is no endogenous model that considers hypoxia and its effect on the brain as an independent factor. Thus, we developed a minimally invasive rat model, which is based on the non-depolarizing muscle blocking agent rocuronium in anesthetized animals. This drug causes respiratory insufficiency by paralysis of the striated muscles. Methods: In this study, 14 rats underwent 12 min of hypoxemia with an oxygen saturation of approximately 60% measured by pulse oximetry; thereafter, animals obtained sugammadex to antagonize rocuronium immediately. Results: Compared to controls (14 rats, anesthesia only), hypoxic animals demonstrated significant morphological alterations in the hippocampus (cell decrease in the CA 1 region) and the cerebellum (Purkinje cell decrease), as well as significant changes in hypoxia markers in blood (Hif2α, Il1β, Tgf1β, Tnfα, S100b, cspg2, neuron-specific enolase), hippocampus (Il1β, Tnfα, S100b, cspg2, NSE), and cerebellum (Hif1α, Tnfα, S100b, cspg2, NSE). Effects were more pronounced in females than in males. Discussion: Consequently, this model is suitable to induce hypoxemia with consecutive global cerebral hypoxia. As significant morphological and biochemical changes were proven, it can be used to investigate therapeutic and preventive drugs for global cerebral hypoxia.

How S100B crosses brain barriers and why it is considered a peripheral marker of brain injury

S100B is a 21-kDa protein that is produced and secreted by astrocytes and widely used as a marker of brain injury in clinical and experimental studies. The majority of these studies are based on measurements in blood serum, assuming an associated increase in cerebrospinal fluid and a rupture of the blood-brain barrier (BBB). Moreover, extracerebral sources of S100B are often underestimated. Herein, we will review these interpretations and discuss the routes by which S100B, produced by astrocytes, reaches the circulatory system. We discuss the concept of S100B as an alarmin and its dual activity as an inflammatory and neurotrophic molecule. Furthermore, we emphasize the lack of data supporting the idea that S100B acts as a marker of BBB rupture, and the need to include the glymphatic system in the interpretations of serum changes of S100B. The review is also dedicated to valorizing extracerebral sources of S100B, particularly adipocytes. Furthermore, S100B per se may have direct and indirect modulating roles in brain barriers: on the tight junctions that regulate paracellular transport; on the expression of its receptor, RAGE, which is involved in transcellular protein transport; and on aquaporin-4, a key protein in the glymphatic system that is responsible for the clearance of extracellular proteins from the central nervous system. We hope that the data on S100B, discussed here, will be useful and that it will translate into further health benefits in medical practice.

Development and validation of a machine learning-based prognostic risk stratification model for acute ischemic stroke

Acute ischemic stroke (AIS) is a most prevalent cause of serious long-term disability worldwide. Accurate prediction of stroke prognosis is highly valuable for effective intervention and treatment. As such, the present retrospective study aims to provide a reliable machine learning-based model for prognosis prediction in AIS patients. Data from AIS patients were collected retrospectively from the Second Affiliated Hospital of Xuzhou Medical University between August 2017 and July 2019. Independent prognostic factors were identified by univariate and multivariate logistic analysis and used to develop machine learning (ML) models. The ML model performance was assessed by area under the receiver operating characteristic curve (AUC) and radar plot. Shapley Additive explanations (SHAP) values were used to interpret the importance of all features included in the predictive model. A total of 677 AIS patients were included in the present study. Poor prognosis was observed in 209 patients (30.9%). Six variables, including neuron specific enolase (NSE), homocysteine (HCY), S-100β, dysphagia, C-reactive protein (CRP), and anticoagulation were included to establish ML models. Six different ML algorithms were tested, and Random Forest model was selected as the final predictive model with the greatest AUC of 0.908. Moreover, according to SHAP results, NSE impacted the predictive model the most, followed by HCY, S-100β, dysphagia, CRP and anticoagulation. Based on the RF model, an online tool was constructed to predict the prognosis of AIS patients and assist clinicians in optimizing patient treatment. The present study revealed that NSE, HCY, CRP, S-100β, anticoagulation, and dysphagia were important factors for poor prognosis in AIS patients. ML algorithms were used to develop predictive models for predicting the prognosis of AIS patients, with the RF model presenting the optimal performance.

Early preclinical plasma protein biomarkers of brain trauma are influenced by early seizures and levetiracetam

OBJECTIVE

We used the lateral fluid percussion injury (LFPI) model of moderate-to-severe traumatic brain injury (TBI) to identify early plasma biomarkers predicting injury, early post-traumatic seizures or neuromotor functional recovery (neuroscores), considering the effect of levetiracetam, which is commonly given after severe TBI.

METHODS

Adult male Sprague-Dawley rats underwent left parietal LFPI, received levetiracetam (200 mg/kg bolus, 200 mg/kg/day subcutaneously for 7 days [7d]) or vehicle post-LFPI, and were continuously video-EEG recorded (n = 14/group). Sham (craniotomy only, n = 6), and naïve controls (n = 10) were also used. Neuroscores and plasma collection were done at 2d or 7d post-LFPI or equivalent timepoints in sham/naïve. Plasma protein biomarker levels were determined by reverse phase protein microarray and classified according to injury severity (LFPI vs. sham/control), levetiracetam treatment, early seizures, and 2d-to-7d neuroscore recovery, using machine learning.

RESULTS

Low 2d plasma levels of Thr231 -phosphorylated tau protein (pTAU-Thr231 ) and S100B combined (ROC AUC = 0.7790) predicted prior craniotomy surgery (diagnostic biomarker). Levetiracetam-treated LFPI rats were differentiated from vehicle treated by the 2d-HMGB1, 2d-pTAU-Thr231 , and 2d-UCHL1 plasma levels combined (ROC AUC = 0.9394) (pharmacodynamic biomarker). Levetiracetam prevented the seizure effects on two biomarkers that predicted early seizures only among vehicle-treated LFPI rats: pTAU-Thr231 (ROC AUC = 1) and UCHL1 (ROC AUC = 0.8333) (prognostic biomarker of early seizures among vehicle-treated LFPI rats). Levetiracetam-resistant early seizures were predicted by high 2d-IFNγ plasma levels (ROC AUC = 0.8750) (response biomarker). 2d-to-7d neuroscore recovery was best predicted by higher 2d-S100B, lower 2d-HMGB1, and 2d-to-7d increase in HMGB1 or decrease in TNF (P < 0.05) (prognostic biomarkers).

SIGNIFICANCE

Antiseizure medications and early seizures need to be considered in the interpretation of early post-traumatic biomarkers.

The kidney-brain pathogenic axis in severe falciparum malaria

Severe falciparum malaria is a medical emergency and a leading cause of death and neurodisability in endemic areas. Common complications include acute kidney injury (AKI) and cerebral malaria, and recent studies have suggested links between kidney and brain dysfunction in Plasmodium falciparum infection. Here, we review these new findings and present the hypothesis of a pivotal pathogenic crosstalk between the kidneys and the brain in severe falciparum malaria. We highlight the evidence of a role for distant organ involvement in the development of cerebral malaria and subsequent neurocognitive impairment post-recovery, describe the challenges associated with current diagnostic shortcomings for both AKI and brain involvement in severe falciparum malaria, and explore novel potential therapeutic strategies.

Isolated transient vertigo due to TIA: challenge for diagnosis and therapy

As a prevalent vertigo disease in the clinic, isolated transient vertigo can present as a vertigo episode without focal signs and always free of symptoms on presentation. Previous studies showed a part of isolated transient vertigo events had a high risk of stroke during follow-up. However, how to discern posterior circulation ischemia become a great challenge for clinicians, especially in emergency, neurology, and ENT departments. Routine besides, hematological, and imaging examinations are often difficult provide a clear etiological diagnosis. Hence, this article reviews current knowledge about the epidemiology, risk factors, offending lesions, and clinical manifestation of transient ischemic attack (TIA) presenting as isolated transient vertigo. In addition, we summarize several advances in besides examinations, serum biomarkers, and imaging technologies to better identify stroke events. Finally, the current situation of therapy was briefly retrospected. Here we present a critical clinical puzzle that needs to be solved in the future. Of note, there is a still lack of high-quality studies in this field. The article reviews the keys to the diagnosis of isolated transient vertigo due to TIA and provides us with more methods to screen for high-risk stroke populations.

Review: Emerging Eye-Based Diagnostic Technologies for Traumatic Brain Injury

The study of ocular manifestations of neurodegenerative disorders, Oculomics, is a growing field of investigation for early diagnostics, enabling structural and chemical biomarkers to be monitored overtime to predict prognosis. Traumatic brain injury (TBI) triggers a cascade of events harmful to the brain, which can lead to neurodegeneration. TBI, termed the "silent epidemic" is becoming a leading cause of death and disability worldwide. There is currently no effective diagnostic tool for TBI, and yet, early-intervention is known to considerably shorten hospital stays, improve outcomes, fasten neurological recovery and lower mortality rates, highlighting the unmet need for techniques capable of rapid and accurate point-of-care diagnostics, implemented in the earliest stages. This review focuses on the latest advances in the main neuropathophysiological responses and the achievements and shortfalls of TBI diagnostic methods. Validated and emerging TBI-indicative biomarkers are outlined and linked to ocular neuro-disorders. Methods detecting structural and chemical ocular responses to TBI are categorised along with prospective chemical and physical sensing techniques. Particular attention is drawn to the potential of Raman spectroscopy as a non-invasive sensing of neurological molecular signatures in the ocular projections of the brain, laying the platform for the first tangible path towards alternative point-of-care diagnostic technologies for TBI.

Discrepancy of C-Reactive Protein, Procalcitonin and Interleukin-6 at Hospitalization: Infection in Patients with Normal C-Reactive Protein, Procalcitonin and High Interleukin-6 Values

C-reactive protein (CRP) or procalcitonin (PCT) alone has limitations in the early detection of infection or inflammation due to shortcomings in specificity and varied cut-off values. Recently, interleukin (IL)-6 has been assessed, but it is not known to what extent the three values are homogeneous in reality. This retrospective study was conducted with two large datasets (discrepancy set with results within 24 h of admission [7149 patients] and follow-up set until 2 weeks of hospital stay [5261 tests]) consisting of simultaneous examinations of CRP, PCT, and IL-6 between January 2015 and August 2021. The specific discrepant group (n = 102, 1.4%) with normal CRP (<10 mg/L) and PCT (<0.1 ng/mL) and high IL-6 (≥100 pg/mL) values was extracted from the discrepancy set. Dimensionality reduction and visualization were performed using Python. The three markers were not clearly clustered after t-distributed stochastic neighbor embedding. Pearson’s correlation coefficients between two markers were substantially low (0.23−0.55). Among the high normalized IL-6 levels (≥0.5) (n = 349), 17.8% and 38.7% of CRP and PCT levels were very low (≤0.01). 9.2% and 13.4% of normal CRP (n = 1522) had high PCT (≥0.5 ng/mL) and IL-6 (≥100 pg/mL) values, respectively. Infection and bacteremia among 102 patients occurred in 36 (35.3%) and 9 (8.8%) patients, respectively. In patients with bacteremia, IL-6 was the first to increase, followed by PCT and CRP. Our study revealed that CRP, PCT, and IL-6 levels were considerably discrepant, which could be misinterpreted if only CRP tests are performed.

Synaptamide Modulates Astroglial Activity in Mild Traumatic Brain Injury

At present, the study of the neurotropic activity of polyunsaturated fatty acid ethanolamides (N-acylethanolamines) is becoming increasingly important. N-docosahexaenoylethanolamine (synaptamide, DHEA) is a highly active metabolite of docosahexaenoic acid (DHA) with neuroprotective, synaptogenic, neuritogenic, and anti-inflammatory properties in the nervous system. Synaptamide tested in the present study was obtained using a chemical modification of DHA isolated from squid Berryteuthis magister liver. The results of this study demonstrate the effects of synaptamide on the astroglial response to injury in the acute (1 day) and chronic (7 days) phases of mild traumatic brain injury (mTBI) development. HPLC-MS study revealed several times increase of synaptamide concentration in the cerebral cortex and serum of experimental animals after subcutaneous administration (10 mg/kg/day). Using immunohistochemistry, it was shown that synaptamide regulates the activation of GFAP- and S100β-positive astroglia, reduce nNOS-positive immunostaining, and stimulates the secretion of neurotrophin BDNF. Dynamics of superoxide dismutase production in synaptamide treatment confirm the antioxidant efficacy of the test compound. We found a decrease in TBI biomarkers such as GFAP, S100β, and IL-6 in the blood serum of synaptamide-treated experimental animals using Western blot analysis. The results indicate the high therapeutic potential of synaptamide in reducing the severity of the brain damage consequences.

Circulating Biomarkers in Long-Term Stroke Prognosis: A Scoping Review Focusing on the South African Setting

Cerebrovascular disease, including both ischaemic and haemorrhagic strokes, remains one of the highest causes of global morbidity and mortality. Developing nations, such as South Africa (SA), are affected disproportionately. Early identification of stroke patients at risk of poor clinical prognosis may result in improved outcomes. In addition to conventional neuroimaging, the role of predictive biomarkers has been shown to be important. Little data exist on their applicability within SA. This scoping review aimed to evaluate the currently available data pertaining to blood biomarkers that aid in the long-term prognostication of patients following stroke and its potential application in the South African setting. This scoping review followed a 6-stage process to identify and critically review currently available literature pertaining to prognostic biomarkers in stroke. An initial 1191 articles were identified and, following rigorous review, 41 articles were included for the purposes of the scoping review. A number of potential biomarkers were identified and grouped according to the function or origin of the marker. Although most biomarkers showed great prognostic potential, the cost and availability will likely limit their application within SA. The burden of stroke is increasing worldwide and appears to be affecting developing countries disproportionately. Access to neuroradiological services is not readily available in all settings and the addition of biomarkers to assist in the long-term prognostication of patients following a stroke can be of great clinical value. The cost and availability of many of the reviewed biomarkers will likely hinder their use in the South African setting.

Effect of Systemic Lidocaine on Postoperative Early Recovery Quality in Patients Undergoing Supratentorial Tumor Resection

Purpose

Lidocaine has been gradually used in general anesthesia. This study was designed to investigate the effect of systemic lidocaine on postoperative quality of recovery (QoR) in patients undergoing supratentorial tumor resection, and to explore its brain-injury alleviation effect in neurosurgical anesthesia.

Patients and Methods

Sixty adult patients undergoing elective supratentorial tumor resection. Patients were randomly assigned either to receive lidocaine (Group L: 1.5 mg/kg bolus completed 10 min before anesthesia induction followed by an infusion at 2.0 mg/kg/h) or to receive normal saline (Group C: received volume-matched normal saline at the same infusion rate). Primary outcome measures were Quality of Recovery-40 (QoR-40) scores on postoperative day (POD) 1 and 2. Plasma concentrations of S100B protein (S100B), neuron specific enolase (NSE), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) before anesthesia induction and at the end of surgery were assessed. Visual Analogue Scale (VAS) scores were assessed at 1, 2, 6, 12, 24 and 48 h after surgery. Perioperative parameters and adverse events were also recorded.

Results

Patients between two groups had comparable baseline characteristics. Global QoR-40 scores on POD 1 and POD 2 were significantly higher (P <0.001) in group L (165.5±3.8 vs 173.7±4.7) than those in group C (155.6±4.0 vs 163.2±4.5); and scores of physical comfort, emotional state, and pain in group L were superior to those in group C (P <0.05). In group L, patients possessed lower plasma concentration of pro-inflammatory factors (IL-6, TNF-α) and brain injury-related factors (S100B, NSE) (P <0.05), consumed less remifentanil and propofol, and experienced lower pain intensity. Multiple linear regression analysis demonstrated age and pain were correlated with postperative recovery quality.

Conclusion

Systemic lidocaine improved early recovery quality after supratentorial tumor resection with general anesthesia, and had certain brain-injury alleviation effects. These benefits may be attributed to the inflammation-alleviating and analgesic properties of lidocaine.

The genetic and epigenetic profile of serum S100β in the Lothian Birth Cohort 1936 and its relationship to Alzheimer's disease

Background: Circulating S100 calcium-binding protein (S100β) is a marker of brain inflammation that has been associated with a range of neurological conditions. To provide insight into the molecular regulation of S100β and its potential causal associations with Alzheimer's disease, we carried out genome- and epigenome-wide association studies (GWAS/EWAS) of serum S100β levels in older adults and performed Mendelian randomisation with Alzheimer's disease. Methods: GWAS (N=769, mean age 72.5 years, sd = 0.7) and EWAS (N=722, mean age 72.5 years, sd = 0.7) of S100β levels were performed in participants from the Lothian Birth Cohort 1936. Conditional and joint analysis (COJO) was used to identify independent loci. Expression quantitative trait locus (eQTL) analyses were performed for lead loci that had genome-wide significant associations with S100β. Bidirectional, two-sample Mendelian randomisation was used to test for causal associations between S100β and Alzheimer's disease. Colocalisation between S100β and Alzheimer's disease GWAS loci was also examined. Results: We identified 154 SNPs from chromosome 21 that associated (P<5x10 -8) with S100β protein levels. The lead variant was located in the S100β gene (rs8128872, P=5.0x10 -17). We found evidence that two independent causal variants existed for both transcription of S100β and S100β protein levels in our eQTL analyses . No CpG sites were associated with S100β levels at the epigenome-wide significant level (P<3.6x10 -8); the lead probe was cg06833709 (P=5.8x10 -6), which mapped to the LGI1 gene. There was no evidence of a causal association between S100β levels and Alzheimer's disease or vice versa and no evidence for colocalisation between S100β and Alzheimer's disease loci. Conclusions: These data provide insight into the molecular regulators of S100β levels. This context may aid in understanding the role of S100β in brain inflammation and neurological disease.

Biomarkers for sepsis: more than just fever and leukocytosis-a narrative review

A biomarker describes a measurable indicator of a patient's clinical condition that can be measured accurately and reproducibly. Biomarkers offer utility for diagnosis, prognosis, early disease recognition, risk stratification, appropriate treatment (theranostics), and trial enrichment for patients with sepsis or suspected sepsis. In this narrative review, we aim to answer the question, "Do biomarkers in patients with sepsis or septic shock predict mortality, multiple organ dysfunction syndrome (MODS), or organ dysfunction?" We also discuss the role of pro- and anti-inflammatory biomarkers and biomarkers associated with intestinal permeability, endothelial injury, organ dysfunction, blood-brain barrier (BBB) breakdown, brain injury, and short and long-term mortality. For sepsis, a range of biomarkers is identified, including fluid phase pattern recognition molecules (PRMs), complement system, cytokines, chemokines, damage-associated molecular patterns (DAMPs), non-coding RNAs, miRNAs, cell membrane receptors, cell proteins, metabolites, and soluble receptors. We also provide an overview of immune response biomarkers that can help identify or differentiate between systemic inflammatory response syndrome (SIRS), sepsis, septic shock, and sepsis-associated encephalopathy. However, significant work is needed to identify the optimal combinations of biomarkers that can augment diagnosis, treatment, and good patient outcomes.

The genetic and epigenetic profile of serum S100β in the Lothian Birth Cohort 1936 and its relationship to Alzheimer's disease

Background: Circulating S100 calcium-binding protein (S100β) is a marker of brain inflammation that has been associated with a range of neurological conditions. To provide insight into the molecular regulation of S100β and its potential causal associations with Alzheimer's disease, we carried out genome- and epigenome-wide association studies (GWAS/EWAS) of serum S100β levels in older adults and performed Mendelian randomisation with Alzheimer's disease. Methods: GWAS (N=769, mean age 72.5 years, sd = 0.7) and EWAS (N=722, mean age 72.5 years, sd = 0.7) of S100β levels were performed in participants from the Lothian Birth Cohort 1936. Conditional and joint analysis (COJO) was used to identify independent loci. Expression quantitative trait locus (eQTL) analyses were performed for lead loci that had genome-wide significant associations with S100β. Bidirectional, two-sample Mendelian randomisation was used to test for causal associations between S100β and Alzheimer's disease. Colocalisation between S100β and Alzheimer's disease GWAS loci was also examined. Results: We identified 154 SNPs from chromosome 21 that associated (P<5x10 -8) with S100β protein levels. The lead variant was located in the S100β gene (rs8128872, P=5.0x10 -17). We found evidence that two independent causal variants existed for both transcription of S100β and S100β protein levels in our eQTL analyses . No CpG sites were associated with S100β levels at the epigenome-wide significant level (P<3.6x10 -8); the lead probe was cg06833709 (P=5.8x10 -6), which mapped to the LGI1 gene. There was no evidence of a causal association between S100β levels and Alzheimer's disease or vice versa and no evidence for colocalisation between S100β and Alzheimer's disease loci. Conclusions: These data provide insight into the molecular regulators of S100β levels. This context may aid in understanding the role of S100β in brain inflammation and neurological disease.

Alarmins (IL-33, sST2, HMGB1, and S100B) as potential biomarkers for schizophrenia

There is growing evidence that immune/inflammatory processes are related to the etiology of schizophrenia. Danger-/damage-associated molecular patterns (DAMPs), also called alarmins, are recognized as inflammatory mediators that play an important role in the development of many infection-induced or sterile inflammatory diseases. The importance of DAMPs particles in various mental disorders is still not clear. Therefore, this study aimed to evaluate serum levels of the most promising alarmins (IL-33, sST2, HMGB1, and S100B), as potent schizophrenia biomarkers. Sixty-eight adult patients with chronic schizophrenia and twenty-nine healthy volunteers were included in this prospective study. Enzyme-linked immunosorbent assay (ELISA) was used to assess the serum concentration of IL-33, sST2, HMGB1, and S100B. We documented that the serum levels of IL-33 (p = 0.006), sST2 (p = 0.02), HMGB1 (p = 0.01), and S100B (p = 0.04) are significantly higher in patients with schizophrenia than in healthy subjects. In male, but not in female, patients with schizophrenia, we found a significant difference in the serum IL-33, sST2, and HMGB1 concentrations as compared to the healthy men. In both male and female patients with schizophrenia, there was no significant difference in the serum concentrations of S100B in comparison to control subjects. In patients with schizophrenia, no significant correlations were noticed neither between any studied alarmins and PANSS scores nor between CDSS scores. Given that all investigated alarmins participate in the course of the neuroinflammatory process, they might be considered as biomarkers of neuroinflammatory process underlying schizophrenia. Based on our observations, it seems that the most useful biological indicator of schizophrenia would be IL-33.

Serum biomarkers and cerebral autoregulation as early warnings of delayed cerebral ischemia risk in patients after aneurysmal subarachnoid haemorrhage

BACKGROUND

Identifying patients at risk of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid haemorrhage (aSAH) remains challenging. This study aimed to evaluate the concentration of serum biomarkers along with cerebral autoregulation impairment on DCI.

METHODS

55 patients suffering from aSAH were enrolled in the study. Serum S100protein B (S100B) was tested both on the day of admission and over three consecutive days following the occurrence of aSAH. Cerebral autoregulation was assessed using a tissue oxygenation index (TOxa) based on near-infrared spectroscopy.

RESULTS

Changes in serum S100B levels interacted with DCI status (presence vs. absence): F = 3.84, p = 0.016. Patients with DCI had higher S100B concentration level on day 3 than those without DCI (3.54 ± 0.50 ng/ml vs. 0.58 ± 0.43 ng/ml, p = 0.001). S100B concentration on day 3 following aSAH predicted DCI (AUC = 0.77, p = 0.006). Raised level of serum S100B on day 3 was related with higher TOxa, thus with impaired cerebral autoregulation (r_S = 0.52,p = 0.031). Multivariate logistic regression analysis showed thatimpaired cerebral autoregulation andelevatedS100B concentration on day 3 increasethe likelihood of DCI.

CONCLUSIONS

Tracking changes in the serum biomarkers concentration along with monitoring of cerebral autoregulation, may play a role in early detection of patients at risk of DCI after aSAH. These results need to be validated in larger prospective cohorts.

Serum S100 Protein Is a Reliable Predictor of Brain Injury After Out-of-Hospital Cardiac Arrest: A Cohort Study

Purpose: To evaluate serum S100 protein at hospital admission and after 48 h in early neuroprognostication of comatose survivors of out-of-hospital cardiac arrest (OHCA). Methods: The study included 48 consecutive patients after OHCA, who survived for at least 72 h after the event. The patients were divided based on their best cerebral performance category (CPC) achieved over a 30 day follow-up period: favorable neurological outcome (CPC 1-2) vs. unfavorable neurological outcome (CPC 3-4). Predictors of an unfavorable neurological outcome were identified by multivariable regression analysis. Analysis of the receiver operating characteristic curve (ROC) was used to determine the cut-off value for S100, having a 0% false-positive prediction rate. Results: Of the 48 patients, 30 (63%) had a favorable and 18 (38%) had an unfavorable neurological outcome. Eleven patients (23%) died over the 30 day follow-up. Increased S100 levels at 48 h after OHCA, but not the baseline S100 levels, were independently associated with unfavorable neurological outcome, with an area under the ROC curve of 0.85 (confidence interval 0.74-0.96). A 48 h S100 value ≥0.37 μg/L had a specificity of 100% and sensitivity of 39% in predicting an unfavorable 30 day neurological outcome. Conclusion: This study showed that S100 values assessed 48 h after an OHCA could independently predict an unfavorable neurological outcome at 30 days.

Plasma miR-9-3p and miR-136-3p as Potential Novel Diagnostic Biomarkers for Experimental and Human Mild Traumatic Brain Injury

Noninvasive, affordable circulating biomarkers for difficult-to-diagnose mild traumatic brain injury (mTBI) are an unmet medical need. Although blood microRNA (miRNA) levels are reportedly altered after traumatic brain injury (TBI), their diagnostic potential for mTBI remains inconclusive. We hypothesized that acutely altered plasma miRNAs could serve as diagnostic biomarkers both in the lateral fluid percussion injury (FPI) model and clinical mTBI. We performed plasma small RNA-sequencing from adult male Sprague-Dawley rats (n = 31) at 2 days post-TBI, followed by polymerase chain reaction (PCR)-based validation of selected candidates. miR-9a-3p, miR-136-3p, and miR-434-3p were identified as the most promising candidates at 2 days after lateral FPI. Digital droplet PCR (ddPCR) revealed 4.2-, 2.8-, and 4.6-fold elevations in miR-9a-3p, miR-136-3p, and miR-434-3p levels (p < 0.01 for all), respectively, distinguishing rats with mTBI from naïve rats with 100% sensitivity and specificity. DdPCR further identified a subpopulation of mTBI patients with plasma miR-9-3p (n = 7/15) and miR-136-3p (n = 5/15) levels higher than one standard deviation above the control mean at <2 days postinjury. In sTBI patients, plasma miR-9-3p levels were 6.5- and 9.2-fold in comparison to the mTBI and control groups, respectively. Thus, plasma miR-9-3p and miR-136-3p were identified as promising biomarker candidates for mTBI requiring further evaluation in a larger patient population.

Can S100B Predict and Evaluate Post-Traumatic Hydrocephalus

OBJECTIVE

Post-traumatic hydrocephalus (PTH) is a common complication of craniocerebral injury. If not diagnosed in time, PTH can lead to clinical deterioration and a poor prognosis. The early diagnosis of PTH can lead to success with early treatment. However, PTH can be easily ignored during rehabilitation. The main purpose of the present study was to investigate whether plasma S100B protein levels can be used as a biochemical predictive index of PTH. We also explored the correlation among S100B protein levels, intracranial pressure, and PTH severity.

METHODS

The data from 235 patients with traumatic brain injury treated from June 2014 to June 2019 in our hospital were retrospectively analyzed. Statistical analysis was performed on 3 serum S100B samples from each patient. The first sample was taken 1-3 days after the injury and surgery. The second sample was harvested during the stable period after treatment, and the third sample was taken when PTH had been confirmed by computed tomography. We analyzed the change in S100B protein levels, and intracranial pressure was measured by lumbar puncture.

RESULTS

A total of 235 patients (Glasgow coma scale score <12) with traumatic brain injury were investigated. Of these 235 patients, 46 (19%) had developed PTH. The first and second S100B samples showed no significant differences between the patients with and without PTH. In the third sample, the S100B level of the patients with PTH was significantly greater than that of the patients without PTH, with a statistically significant difference. Statistical analysis found no correlation between the S100B level and the severity of PTH.

CONCLUSIONS

Measurements of serum S100B can be used to predict for PTH. We found a positive correlation between S100B levels and intracranial pressure but no correlation with the severity of PTH. Thus, serum S100B could have important clinical significance for the early detection and evaluation of PTH.

Integrating Network Pharmacology and Experimental Models to Investigate the Mechanism of Huanglian Jiedu Decoction on Inflammatory Injury Induced by Cerebral Ischemia

Unlike single-target Western medicines, traditional Chinese medicines (TCMs) exhibit diverse curative effects against multiple diseases through their "multicomponent" and "multitarget" manifestations. However, the material basis of the major therapeutic diseases and TCM underlying molecular mechanisms remain to be challenged. In the current study, we applied, for the first time, an integrated strategy that combines network pharmacology and experimental evaluation and explored and demonstrated the underlying possible mechanisms of a classic TCM formula, Huanglian Jiedu Decoction (HLJD), in the treatment of cerebral ischemia. First, the herb compound, protein compound, and GO-BP and KEGG pathways were constructed to predict the material basis of HLJD in the treatment of cerebral ischemia and explore the underlying molecular mechanisms. Network pharmacology analysis showed that HLJD treats cerebral ischemia mainly through its anti-inflammatory effect. We used molecular docking to verify that HLJD components have good binding activities to the arachidonic acid pathway enzymes, cyclooxylipase-2 (COX-2) and 5-lipoxygenase (5-LOX). Next, based on the prediction by the network pharmacology analysis, the rat model of middle cerebral artery occlusion (MCAO) was established to verify the efficacy of HLJD. The results showed that HLJD reduces the degree of brain injury in MCAO rats, probably by inhibiting the expression of the 5-LOX pathway and inflammatory response. In conclusion, our study demonstrates the effectiveness of integrating network pharmacology with an experimental study for material basis of the major therapeutic diseases and the underlying molecular mechanisms of TCM.

The blood-brain barrier dysfunction in sepsis

Sepsis is a life-threatening organ dysfunction triggered by a dysregulated host immune response attempting to eliminate the infection. After hospital discharge, half of the sepsis survivors recover, one-third of the patients die the following year, and one-sixth have a long-term cognitive impairment, including memory dysfunction, anxiety, depression, and post-traumatic stress disorder. The infection triggers the host immune response, and both can cause vascular endothelial damage, interrupting tight junctions proteins; consequently, the blood-brain barrier (BBB) breaks down, allowing and facilitating the entry of peripheral immune cells into the brain, which triggers or exacerbates the activation of glial cells and neuroinflammation. The focus of this review is to identify biochemical abnormalities induced by sepsis, which is associated with BBB dysfunction; provide evidence of biomarkers involved in the tight junction disruption and BBB damage, and draw attention to the role of the BBB as a bridge between systemic infection and brain inflammation.

The dynamic change of serum S100B levels from day 1 to day 3 is more associated with sepsis-associated encephalopathy

We investigated the role of dynamic changes of serum levels S100B protein in brain injury and poor outcome of sepsis. This is a prospective cohort study designed to include 104 adult patients with sepsis who are admitted to ICU from Jan 2015 to Aug 2016. Sepsis was defined as sepsis 3.0. Patients with a GCS score of <15, or at least one positive CAM-ICU score were thought to have brain dysfunction. 59 patients were diagnosed with SAE and the rest 45 patients were diagnosed with non-SAE. Serum S100B was measured on day 1 and 3 after ICU admission. Primary outcomes included brain dysfunction and 28-day/180-day mortality. The SAE group showed a significantly higher APACHE II score, SOFA scores, length of ICU stay, 28-day and 180-day mortality, serum S100B levels on day 1 and day 3. S100B levels on day 1 of 0.226 μg/L were diagnostic for SAE with 80.0% specificity and 66.1% sensitivity, and the area under (AUC) the curve was 0.728, S100B levels on day 3 of 0.144 μg/L were diagnostic for SAE with 84.44% specificity and 69.49% sensitivity, and the AUC was 0.819. In addition, the AUC for S100B on day 3 for predicting 180-day mortality was larger than for S100B on day 1 (0.731 vs. 0.611). Multiple logistic regression analysis showed that S100B3 (p = 0.001) but not S100B1 (p = 0.927) were independently correlated with SAE. Kaplan-Meier survival analysis showed that patients with S100B levels higher than 0.144 μg/L had a lower probability of survival at day 180. There were more patients with encephalopathy and a higher 28-day or 180-day mortality in the ΔS100B + group than in the ΔS100B- group. Multiple logistic regression analysis showed that SAE and IL-6 on day 3 were independently correlated with S100B dynamic increase. These findings suggest that elevated serum S100B levels on day 3 and the dynamic changes of serum S100B levels from day three to one were more associated with brain dysfunction and mortality than that on day 1 in patients with sepsis.

Diagnostic Value of Serum Biomarkers for Differentiating Central and Peripheral Causes of Acute Vertigo

Background: In patients presenting with acute vertigo or dizziness, distinguishing central from peripheral is a diagnostic challenge. This study investigated potential serum markers for differentiating central and peripheral vertigo in patients with acute-onset vertigo.

Methods: This prospective case–control study recruited consecutive participants from the Emergency Department, including patients with acute-onset vertigo or dizziness within 12 h and control subjects. We used enzyme-linked immunosorbent assays to measure the serum S100β, NSE, BDNF, GFAP, and IL-6 levels during the acute period.

Results: The 114 study subjects included 28 patients with central vertigo (CV), 49 patients with peripheral vertigo (PV), and 37 age- and sex-matched healthy controls. No differences were found in risk factor distribution among the three groups. In patients with CV, the serum NSE and S100β levels were significantly (p < 0.05) elevated compared with the control and PV groups. The ROC analysis gave an AUC of 0.843 (95% CI = 0.753–0.932) for NSE and 0.787 (95% CI = 0.687–0.886) for S100β for predicting CV. However, there were no significant differences in the serum GFAP and BDNF levels among the CV, PV, and control groups.

Conclusions: Serum NSE and S100β levels are significantly higher in patients with CV, such as occurs with posterior circulation ischemic stroke or vertebrobasilar insufficiency. S100β and NSE may serve as serum biomarkers for differentiating between CV and PV in patients with acute-onset vertigo.

Biospecimens and Molecular and Cellular Biomarkers in Aneurysmal Subarachnoid Hemorrhage Studies: Common Data Elements and Standard Reporting Recommendations

INTRODUCTION

Development of clinical biomarkers to guide therapy is an important unmet need in aneurysmal subarachnoid hemorrhage (SAH). A wide spectrum of plausible biomarkers has been reported for SAH, but none have been validated due to significant variabilities in study design, methodology, laboratory techniques, and outcome endpoints.

METHODS

A systematic review of SAH biomarkers was performed per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The panel's recommendations focused on harmonization of (1) target cellular and molecular biomarkers for future investigation in SAH, (2) standardization of best-practice procedures in biospecimen and biomarker studies, and (3) experimental method reporting requirements to facilitate meta-analyses and future validation of putative biomarkers.

RESULTS

No cellular or molecular biomarker has been validated for inclusion as "core" recommendation. Fifty-four studies met inclusion criteria and generated 33 supplemental and emerging biomarker targets. Core recommendations include best-practice protocols for biospecimen collection and handling as well as standardized reporting guidelines to capture the heterogeneity and variabilities in experimental methodologies and biomarker analyses platforms.

CONCLUSION

Significant variabilities in study design, methodology, laboratory techniques, and outcome endpoints exist in SAH biomarker studies and present significant barriers toward validation and translation of putative biomarkers to clinical use. Adaptation of common data elements, recommended biospecimen protocols, and reporting guidelines will reduce heterogeneity and facilitate future meta-analyses and development of validated clinical biomarkers in SAH.

Comparison of the effect of propofol and desflurane on S-100β and GFAP levels during controlled hypotension for functional endoscopic sinus surgery: A randomized controlled trial

BACKGROUND

Although surgical field visualization is important in functional endoscopic sinus surgery (FESS), the complications associated with controlled hypotension for surgery should be considered. Intraoperative hypotension is associated with postoperative stroke, leading to subsequent hypoxia with potential neurologic injury. We investigated the effect of propofol and desflurane anesthesia on S-100β and glial fibrillary acidic protein (GFAP) levels which are early biomarkers for cerebral ischemic change during controlled hypotension for FESS.

METHODS

For controlled hypotension during FESS, anesthesia was maintained with propofol/remifentanil in propofol group (n = 30) and with desflurane/remifentanil in desflurane group (n = 30). For S-100β and GFAP assay, blood samples were taken at base, 20 and 60 minutes after achieving the target range of mean arterial pressure, and at 60 minutes after surgery.

RESULTS

The base levels of S-100β were 98.04 ± 78.57 and 112.61 ± 66.38 pg/mL in the propofol and desflurane groups, respectively. The base levels of GFAP were 0.997 ± 0.486 and 0.898 ± 0.472 ng/mL in the propofol and desflurane groups, respectively. The S-100β and GFAP levels were significantly increased in the study period compared to the base levels in both groups (P ≤ .001). There was no significant difference at each time point between the 2 groups.

CONCLUSION

On comparing the effects of propofol and desflurane anesthesia for controlled hypotension on the levels of S-100β and GFAP, we noted that there was no significant difference in S-100β and GFAP levels between the 2 study groups.

CLINICAL TRIAL REGISTRATION

Available at: http://cris.nih.go.kr, KCT0002698.

The usefulness of neuron-specific enolase in cerebrospinal fluid to predict neurological prognosis in cardiac arrest survivors who underwent target temperature management: A prospective observational study

AIM

Cerebrospinal fluid (CSF) neuron-specific enolase (NSE) levels increase ahead of serum NSE levels in patients with severe brain injury. We examined the prognostic performance between CSF NSE and serum NSE levels in out-of-cardiac arrest (OHCA) survivors who had undergone target temperature management (TTM).

METHODS

This single-centre prospective observational study included OHCA patients who had undergone TTM. NSE levels were assessed in blood and CSF samples obtained immediately (Day 0), and at 24 h (Day 1), 48 h (Day 2), and 72 h (Day 3) after return of spontaneous circulation (ROSC). The primary outcome was the 6-month neurological outcome.

RESULTS

We enrolled 34 patients (males, 24; 70.6%), and 16 (47.1%) had a poor neurologic outcome. CSF NSE and serum NSE values were significantly higher in the poor outcome group compared to the good outcome group at each time point, except for serum Day 0. CSF NSE and serum NSE had an area under curve (AUC) of 0.819-0.972 and 0.648-0.920, respectively. CSF NSE prognostic performances were significantly higher than serum NSE levels at Day 1 and showed excellent AUC values (0.969; 95% confidence interval [CI] 0.844-0.999) and high sensitivity (93.8%; 95% CI 69.8-99.8) at 100% specificity.

CONCLUSION

We found CSF NSE values were highly predictive and sensitive markers of 6-month poor neurological outcome in OHCA survivors treated with TTM at Day 1 after ROSC. Therefore, CSF NSE levels at day 1 after ROSC can be a useful early prognosticator in OHCA survivors.

The Beneficial Effects of Raffinee in Permanent Occulted Stroke Mice

Ischemic stroke is a major cause of disability and mortality globally. Although thrombolytic therapy is routinely adopted in cases of ischemic stroke, various alternative natural neuroprotectants are also used as effective adjuvant therapies to recover neurofunction following ischemic stroke. Raffinee, a natural fermented product with strong antioxidant and neuroprotective activities, has antiatherogenic effects in animals and has exhibited neuroprotective effects in a clinical trial by recovering motor and sensory function following spinal cord lesion. This study reveals the advantageous effects of Raffinee on PC12 cells by decreasing hypoxia-induced apoptosis in mice with permanent middle cerebral artery occlusion (pMCAO) by increasing the levels of neurotrophic factors such as S100β, reducing serum inflammatory factors such as matrix metalloproteinases (MMP)-9/MMP-2 ratio, tumor necrosis factor-α, and interleukin (IL)-6 level, and increasing IL-10 levels. Significantly reduced brain infarct volume along with a favorable survival ratio was observed for pMCAO mice that received Raffinee, suggesting a neuroprotective potential of Raffinee in cases of acute ischemic stroke by suppressing apoptosis.

A Review of MicroRNA Biomarkers in Traumatic Brain Injury

There is growing public concern surrounding traumatic brain injury (TBI). TBI can cause significant morbidity, and the long-term sequelae are poorly understood. TBI diagnosis and management rely on patient-reported symptoms and subjective clinical assessment. There are no biologic tools to detect mild TBI or to track brain recovery. Emerging evidence suggests that microRNAs (miRNAs) may provide information about the injured brain. These tiny epigenetic molecules are expressed throughout the body. However, they are particularly important in neurons, can cross the blood-brain barrier, and are securely transported from cell to cell, where they regulate gene expression. miRNA levels may identify patients with TBI and predict symptom duration. This review synthesizes miRNA findings from 14 human studies. We distill more than 291 miRNAs to 17 biomarker candidates that overlap across multiple studies and multiple biofluids. The goal of this review is to establish a collective understanding of miRNA biology in TBI and identify clinical priorities for future investigations of this promising biomarker.

Association of IL-13, S100B, and TLR-7 Gene Polymorphisms with Enterovirus 71 Infection in Hand, Foot, and Mouth Disease in China

AIM

This study was conducted to determine if single nucleotide polymorphisms within the interleukin (IL)-13 (rs20541 locus), the S100B (rs9722 locus), and the toll-like receptor (TLR)-7 (rs179019 and rs3853839 loci) genes are associated with the clinical severity of disease caused by enterovirus 71 (EV71) in children suffering from hand, foot, and mouth disease (HFMD).

MATERIALS AND METHODS

A total of 355 children, diagnosed with HFMD, were divided into two groups: severe (totaling 162 cases) and mild (totaling 193 cases). Three hundred healthy children were recruited as a control group. The gene polymorphisms of the rs20541 locus in the IL-13 gene; the rs9722 locus in the S100B gene; and the rs179019 and the rs3853839 loci in the TLR-7 gene were analyzed with Sanger sequencing. The expression levels of IL-13, S100B, interferon (IFN)-α, IL-6 and the relative expression level of TLR-7 were calculated for each genotype.

RESULTS

This study demonstrated that the T allele at the rs9722 locus of the S100B gene was a significant risk factor for severe HFMD. The rs3853839 C allele of the TLR-7 gene was also a risk factor for severe HFMD in both male and female patients. The G allele at the rs20541 locus of IL-13 gene and the A allele at the rs179019 locus of the TLR-7 gene were not risk factors for severe HFMD in either male or female patients.

CONCLUSION

The T allele at the rs9722 locus of S100B gene is a risk factor for the severe HFMD caused by EV71 infection, of which the mechanism may be due to the promotion of S100B protein secretion. The allele C at TLR-7 rs3853839 locus is a risk factor for the severe HFMD caused by EV71 infection, which may be related to a reduction of the relative expression of TLR-7, IFN-α, and IL-6.

Combination of S100B and procalcitonin improves prognostic performance compared to either alone in patients with cardiac arrest: A prospective observational study

This study aimed to determine whether the combination of procalcitonin (PCT) and S100B improves prognostic performance compared to either alone in cardiac arrest (CA) patients treated with targeted temperature management (TTM).We performed a prospective cohort study of CA patients treated with TTM. PCT and S100B levels were obtained at 0, 24, 48, and 72 hours after return of spontaneous circulation. The prognostic performance was analyzed using each marker and the combination of the 2 markers for predicting poor neurological outcome at 3 months and mortality at 14 days and 3 months.A total of 97 patients were enrolled, of which 67 (69.1%) had poor neurological outcome. S100B showed a better prognostic performance (area under the curve [AUC], 0.934; sensitivity, 77.6%; and specificity, 100%) than PCT (AUC, 0.861; sensitivity, 70.2%; and specificity, 83.3%) with the highest prognostic value at 24 hours. The combination of 24-hour PCT and S100B values (S100B ≥0.2 μg/L or PCT ≥6.6 ng/mL) improved sensitivity (85.07%) compared with S100B alone. In multivariate analysis, PCT was associated with mortality at 14 days (odds ratio [OR]: 1.064, 95% confidence interval [CI]: 1.014-1.118), whereas S100B was associated with neurological outcomes at 3 months (OR: 9.849, 95% CI: 2.089-46.431).The combination of PCT and S100B improved prognostic performance compared to the use of either biomarker alone in CA patient treated with TTM. Further studies that will identify the optimal cutoff values for these biomarkers must be conducted.

[Intensive care treatment of traumatic brain injury in multiple trauma patients : Decision making for complex pathophysiology]

Traumatic brain injury (TBI) and hemorrhagic shock due to uncontrolled bleeding are the major causes of death after severe trauma. Mortality rates are threefold higher in patients suffering from multiple injuries and additionally TBI. Factors known to impair outcome after TBI, namely hypotension, hypoxia, hypercapnia, acidosis, coagulopathy and hypothermia are aggravated by the extent and severity of extracerebral injuries. The mainstays of TBI intensive care may be, at least temporarily, contradictory to the trauma care concept for multiple trauma patients. In particular, achieving normotension in uncontrolled bleeding situations, maintenance of normocapnia in traumatic lung injury and thromboembolic prophylaxis are prone to discussion. Due to an ongoing uncertainty about the definition of normotensive blood pressure values, a cerebral perfusion pressure-guided cardiovascular management is of key importance. In contrast, there is no doubt that early goal directed coagulation management improves outcome in patients with TBI and multiple trauma. The timing of subsequent surgical interventions must be based on the development of TBI pathology; therefore, intensive care of multiple trauma patients with TBI requires an ongoing and close cooperation between intensivists and trauma surgeons in order to individualize patient care.

Serum S100B levels in patients with depression

BACKGROUND

The biochemical basis of depression has been related to blood-brain barrier (BBB) allowing/restricting a number of components to enter the brain milieu from the peripheral plasma milieu. S100B has been associated with BBB damage and is used as a marker of its integrity. Several studies have reported that depressive patients have increased levels of S100B in serum and cerebrospinal fluid.

MATERIALS AND METHODS

Forty-two confirmed cases of depression, 13-25 years of ages were recruited from the Department of Psychiatry, All India Institute of Medical Sciences during the period from January 2013 to June 2014 along with 42 healthy controls of comparable age and sex. Psychometric evaluation of the patients and controls was done to assess the severity of depression using Beck's Depression Inventory-II and Hamilton Depression Rating Scale. Medical assessment and laboratory investigations were done. Serum S100B levels were measured using Sandwich ELISA. The results obtained were statistically analyzed.

RESULTS

Levels of serum S100B were significantly elevated in patients with major depression as compared to controls. Significantly higher levels of S100B were seen only in females as compared to their healthy counterparts. Serum S100B was higher in depressed participants with the recurrent disorder than those with single episode. No correlation of levels of this marker was seen with clinical severity of the patients. It was found that with increased duration of illness for which the patient was being treated with antidepressants, the patients had higher levels of S100B.

CONCLUSIONS

Serum S100B can be used as a biomarker of depression.

Non-Coding RNAs to Aid in Neurological Prognosis after Cardiac Arrest

Cardiovascular disease in general, and sudden cardiac death in particular, have an enormous socio-economic burden worldwide. Despite significant efforts to improve cardiopulmonary resuscitation, survival rates remain low. Moreover, patients who survive to hospital discharge have a high risk of developing severe physical or neurological symptoms. Being able to predict outcomes after resuscitation from cardiac arrest would make it possible to tailor healthcare approaches, thereby maximising efforts for those who would mostly benefit from aggressive therapy. However, the identification of patients at risk of poor recovery after cardiac arrest is still a challenging task which could be facilitated by novel biomarkers. Recent investigations have recognised the potential of non-coding RNAs to aid in outcome prediction after cardiac arrest. In this review, we summarize recent discoveries and propose a handful of novel perspectives for the use of non-coding RNAs to predict outcome after cardiac arrest, discussing their use for precision medicine.

S100B Serum Level as a Mortality Predictor for Traumatic Brain Injury: A Meta-Analysis

BACKGROUND:

The pathogenesis of inflammatory neuronal cell damage will continue after traumatic brain injury in which contributed to subsequent mortality. Serum S100B levels were shown to be an early predictor of mortality due to traumatic brain injury.

AIM:

This Meta-Analysis will analyse the mean and diagnostic strength of serum S100B levels between survived and died subjects with head injuries based on the various follow-up times of nine studies.

METHODS:

We conducted a meta-anelysis in accordance with PRISMA guidelines and adhering to Cochrane Handbook for Systematic Review of Interventions. Literature search was conducted on March 16, 2018 from Medline and Scopus in the past 10 years, using various keywords related to S100, brain injury, and outcome. Duplicate journals were sorted out via EndNote. Included articles were as follows: original data from the group, clinical trials, case series, patients undergoing serum S100B levels with both short- and long-term follow-up mortality. Data were collected for mortality, serum S100B levels, and its diagnostic strength. All data were analyzed using Review Manager 5.3 (Cochrane, Denmark).

RESULTS:

The results of the meta-analysis showed a significant difference in S100B levels between survived and died subjects with head injuries on overall follow-up timeline (0.91, 95.9% CI 0.7-1.12, I2 = 98%, p < 0.001), during treatment (1.43, 95% CI 0.97 to 1.89, I2 = 98%, p < 0.001), or 6 months (0.19; 95%CI 0.1-0.29, I2 = 76%, p < 0.001) with an average threshold value that varies according to the study method used. The mean diagnostic strength was also promising to predict early mortality (sensitivity of 77.18% and 92.33%, specificity of 78.35% and 50.6%, respectively).

CONCLUSION:

S100B serum levels in the future will be potential biomarkers, and it is expected that there will be standardised guidelines for their application.

Normothermic versus hypothermic cardiopulmonary bypass in low-risk paediatric heart surgery: a randomised controlled trial

OBJECTIVE

To compare normothermic (35°C-36°C) versus hypothermic (28°C) cardiopulmonary bypass (CPB) in paediatric patients undergoing open heart surgery to test the hypothesis that normothermic CPB perfusion maintains the functional integrity of major organ systems leading to faster recovery.

METHODS

Two single-centre, randomised controlled trials (known as Thermic-1 and Thermic-2, respectively) were carried out to compare the effectiveness and acceptability of normothermic versus hypothermic CPB in children with congenital heart disease undergoing open heart surgery. In both studies, the co-primary clinical outcomes were duration of inotropic support, intubation time and postoperative hospital stay.

RESULTS

In total, 200 participants were recruited; 59 to the Thermic-1 study and 141 to the Thermic-2 study. 98 patients received normothermic CPB and 102 patients received hypothermic CPB. There were no significant differences between the treatment groups for any of the co-primary outcomes: inotrope duration HR=1.01, 95% CI (0.72 to 1.41); intubation time HR=1.14, 95% CI (0.86 to 1.51); postoperative hospital stay HR=1.06, 95% CI (0.80 to 1.40). Differences favouring normothermia were found in urea nitrogen at 2 days geometric mean ratio (GMR)=0.86 95% CI (0.77 to 0.97); serum creatinine at 3 days GMR=0.89, 95% CI (0.81 to 0.98); urinary albumin at 48 hours GMR=0.32, 95% CI (0.14 to 0.74) and neutrophil gelatinase-associated lipocalin at 4 hours GMR=0.47, 95% CI (0.22 to 1.02), but not at other postoperative time points.

CONCLUSIONS

Normothermic CPB is as safe and effective as hypothermic CPB and can be routinely adopted as a perfusion strategy in low-risk infants and children undergoing open heart surgery.

TRIAL REGISTRATION NUMBER

ISRCTN93129502.

Alarmins of the extracellular space

The ability of the immune system to discriminate between healthy-self, abnormal-self, and non-self has been attributed mainly to alarmins signaling as "danger signals". It is now evident, however, that alarmins are much more complex and can perform specialized functions that can regulate a wide spectrum of processes ranging from propagation of disease to tissue homeostasis. As such, alarmins and their signaling mechanisms are now actively pursued as therapeutic targets. The clinical utility of alarmins requires an understanding of their specific localization. Specifically, many alarmins can function paradoxically depending upon their localization, intra or extracellular. The present review focuses upon alarmin presence and differential expression in the extracellular space versus within the cell and how variation of the localization of alarmins can reveal important mechanistic insights into alarmin functions and their efficacy as biomarkers of disease and therapeutic targets.

Brain injury markers: S100 calcium-binding protein B, neuron-specific enolase and glial fibrillary acidic protein in children with diabetic ketoacidosis

BACKGROUND

To investigate serum levels of brain injury markers in diabetic ketoacidosis (DKA) and the relation of these markers with clinical and radiological findings of brain injury and laboratory results.

METHODS

Twenty-nine patients with DKA, 30 with type 1 diabetes mellitus (T1DM), and 35 healthy children were included. Clinical and laboratory findings, and the Glasgow Coma Scale (GCS) were recorded. In the DKA group, neuron-specific enolase (NSE), S100 calcium-binding protein B (S100B) and glial fibrillary acidic protein (GFAP) levels were measured at baseline and 6 and 12 hours after treatment. Magnetic resonance imaging was performed in the DKA group to demonstrate any brain injury.

RESULTS

No clinical or radiological findings of brain injury were found in any of the patients with DKA. In the DKA group, S100B was significantly higher than the healthy control and T1DM groups, while GFAP and NSE levels were not different from controls and T1DM patients. No significant differences were found in GFAP, NSE and S100B levels according to severity of DKA, diabetes duration and GCS.

CONCLUSION

NSE and GFAP levels do not increase in DKA patients without overt brain injury. Elevated levels of S100B, which is also synthesized from non-neuronal tissues, might arise from peripheral sources. A lack of concurrent increase in serum levels of these brain injury markers might result from the yet intact blood brain barrier or a true absence of neuronal damage. In order to reveal subclinical brain injury related to DKA, there is a need for studies concurrently assessing neurocognitive functions.

Biofluid biomarkers of traumatic brain injury

PRIMARY OBJECTIVE

The purpose of this paper is to review the clinical and research utility and applications of blood, cerebrospinal fluid (CSF), and cerebral microdialysis biomarkers in traumatic brain injury (TBI).

RESEARCH DESIGN

Not applicable.

METHODS AND PROCEDURES

A selective review was performed on these biofluid biomarkers in TBI.

MAIN OUTCOME AND RESULTS

Neurofilament heavy chain protein (NF-H), glial fibrillary acidic protein (GFAP), ubiquitin C-terminal hydrolase-L1 (UCHL1), neuron-specific enolase (NSE), myelin basic protein (MBP), tau, and s100β blood biomarkers are elevated during the acute phase of severe head trauma but have key limitations in their research and clinical applications to mild TBI (mTBI). CSF biomarkers currently provide the best reflection of the central nervous system (CNS) pathobiological processes in TBI. Both animal and human studies of TBI have demonstrated the importance of serial sampling of biofluids and suggest that CSF biomarkers may be better equipped to characterize both TBI severity and temporal profiles.

CONCLUSIONS

The identification of biofluid biomarkers could play a vital role in identifying, diagnosing, and treating the underlying individual pathobiological changes of TBI. CNS-derived exosomes analyzed by ultra-high sensitivity detection methods have the potential to identify blood biomarkers for the range of TBI severity and time course.

S100β in newborns after C-section with general vs. epidural anesthesia: a prospective observational study

BACKGROUND

Preclinical evidence suggests that general anesthetics can dose dependently induce neurodegeneration in the developing brains of animals which can be reliably determined by measurement of blood S100β, but this correlation remains unclear in humans. We hypothesized that S100β would not be increased in cord arterial blood of fetuses exposed briefly to general anesthetics during a C-section, compared with epidural anesthesia.

METHODS

A prospective observational clinical study comparatively measured changes of brain damage biomarker S100β ratio of umbilical artery over vein (changes after fetus circulation) immediately after delivery under C-section with either epidural or general anesthesia. Newborn blood gas measurements, APGAR scores, and maternal well-being were also compared.

RESULTS

Compared with epidural anesthesia, general anesthesia resulted in the lower S100β ratio of umbilical artery over the vein (medium 2.64 [quartiles 1.39, 3.45] vs. medium 1.59 [quartiles 0.88, 2.01], P = 0.031), without changing the S100β level in the vein of the mother. There was no significant difference between general and epidural anesthesia when comparing other maternal and newborn parameters.

CONCLUSION

S100β levels in newborn after C-section is lower with general anesthesia than epidural anesthesia, with unclear mechanisms.

Serum levels of S100B from jugular bulb as a biomarker of poor prognosis in patients with severe acute brain injury

AIMS/BACKGROUND

To evaluate the correlation between protein S100B concentrations measured in the jugular bulb as well as at peripheral level and the prognostic usefulness of this marker.

METHODS

A prospective study of all patients admitted to the intensive care unit with acute brain damage was carried out. Peripheral and jugular bulb blood samples were collected upon admission and every 24h for three days. The endpoints were brain death diagnosis and the Glasgow Outcome Scale score after 6months.

RESULTS

A total of 83 patients were included. Jugular protein S100B levels were greater than systemic levels upon admission and also after 24 and 72h (mean difference>0). Jugular protein S100B levels showed acceptable precision in predicting brain death both upon admission [AUC 0.67 (95% CI 0.53-0.80)] and after 48h [AUC 0.73 (95% CI 0.57-0.89)]. Similar results were obtained regarding the capacity of jugular protein S100B levels upon admission to predict an unfavourable outcome (AUC 0.69 (95% CI 0.56-0.79)). The gradient upon admission (jugular-peripheral levels) showed its capacity to predict the development of brain death [AUC 0.74 (95% CI 0.62-0.86)] and together with the Glasgow Coma Scale constituted the independent factors associated with the development of brain death.

CONCLUSION

Regional protein S100B determinations are higher than systemic determinations, thus confirming the cerebral origin of protein S100B. The transcranial protein S100B gradient is correlated to the development of brain death.

Neuroprotective effect of selective antegrade cerebral perfusion during prolonged deep hypothermic circulatory arrest: Cerebral metabolism evidence in a pig model

Objective:

The aim of this study was to elucidate the mechanism of cerebral injury and to evaluate selective antegrade cerebral perfusion (SACP) as a superior neuroprotective strategy for prolonged deep hypothermic circulatory arrest (DHCA).

Methods:

Twelve pigs (6–8-week old) were randomly assigned to DHCA alone (n=6) and DHCA with SACP (n=6) at 18°C for 80 min groups. Serum S100 was determined using an immunoassay analyzer. The concentrations of cerebral dialysate glucose, lactate, pyruvate, glycerol, and glutamate were measured using a microdialysis analyzer.

Results:

Compared with a peak at T4 (after 60 min of rewarming) in the DHCA group, the serum S100 in the SACP group was significantly lower throughout the study. The DHCA group was susceptible to significant increases in the levels of lactate, glycerol, and glutamate and the ratio of lactate/pyruvate as well as decreases in the level of glucose. These microdialysis variables showed only minor changes in the SACP group. There was a positive correlation between cerebral lactate and intracranial pressure during reperfusion in the DHCA group. However, the apoptosis index and C-FOS protein levels were lower in the SACP group.

Conclusion:

Metabolic dysfunction is involved in the mechanism of cerebral injury. SACP is a superior neuroprotective strategy for both mild and prolonged DHCA.

Serum Levels of S100b and NSE Proteins in Patients with Non-Transfusion-Dependent Thalassemia as Biomarkers of Brain Ischemia and Cerebral Vasculopathy

Patients with non-transfusion-dependent thalassemia (NTDT) are at risk of developing brain ischemia. Transcranial Doppler (TCD) has been established as a useful screening tool of cerebrovascular disease in patients with sickle cell disease. Proteins neuron specific enolase (NSE) and S100B are biomarkers that reflect CNS injury. The purpose of this study is to evaluate cerebral vessel vasculopathy and brain damage in NTDT patients using non-invasive methods as TCD and measurement serum levels of NSE and S100B. We included in our study 30 patients with NTDT, aged between 8 and 62 years old (mean: 29.4, median: 32) who presented in our Unit for regular follow-up. We performed in all patients a non-imaging TCD examination and have measured serum S100, NSE and lactate dehydrogenase (LDH) levels. We investigated the possible correlation between TCD results and S100B, NSE and LDH levels as well as between NSE-LDH and S100B-LDH levels by regression analysis. We found a statistically significant relationship for both NSE, S100B with LDH. We also found a statistically significant relationship for S100B and time-averaged mean velocity (TAMV)/peak velocity of left middle cerebral artery (MCA), NSE and pulsatility index (PI)/resistive index (RI) of the left posterior cerebral artery (PCA). TCD results correlated with biomarkers for brain ischemia. This finding enhances the role of TCD as a screening tool for brain ischemia in patients with NTDT.

Prognostic Value of Early S100 Calcium Binding Protein B and Neuron-Specific Enolase in Patients with Poor-Grade Aneurysmal Subarachnoid Hemorrhage: A Pilot Study

BACKGROUND

This prospective study was undertaken to investigate the value of early S100 calcium binding protein B (S100B) and neuron-specific enolase (NSE) in prognosticating outcome in patients with poor-grade aneurysmal subarachnoid hemorrhage and to develop a statistical model and cutoff values for clinical practice.

METHODS

Between 2012 and 2014, patients with poor-grade subarachnoid hemorrhage (Hunt and Hess grade 3-5) who were admitted within 24 hours after hemorrhage were prospectively enrolled. Serum NSE and S100B levels were assayed once daily during the first 3 days after hemorrhage. Patient characteristics, Glasgow Coma Scale score, Hunt and Hess grade, and Fisher grade at admission were recorded. Glasgow Outcome Scale (GOS) score was obtained at 6 months and dichotomized as poor (score 1-3) or good (score 4-5). Logistic regression and receiver operating characteristic curve were used to assess the value of S100B and NSE in predicting outcome, and cutoff values were calculated using conditional interference trees.

RESULTS

The study included 52 patients. Hunt and Hess grade was 3 in 23 patients, 4 in 15 patients, and 5 in 14 patients. S100B range was 0.07-5.62 μg/L (mean 0.87 μg/L ± 1.06). NSE range was 5.7-94.2 μg/L (mean 16.1 μg/L ± 10.5). At 6-month follow-up, 23 patients (44.2%) had a poor outcome, and 29 patients (55.8%) had a good outcome. Both S100B at day 1 (P = 0.004; cutoff 0.202 μg/L) and NSE at day 1 (P = 0.047; cutoff 9.4 μg/L) predicted good outcome with a specificity of 100%. The specificity of mean S100B in detecting patients with poor outcome reached 100% (P = 0.003) when combined with mean NSE levels.

CONCLUSIONS

S100B and NSE measured during the first 3 days after hemorrhage showed, separately and combined, a significant predictive value in prognosticating clinical outcome in patients with poor-grade subarachnoid hemorrhage. A multicenter study with a large patient cohort is necessary to validate the above-mentioned cutoff values for clinical practice.

S-100β and Antioxidant Capacity in Cerebrospinal Fluid during and after Thoracic Endovascular Aortic Repair

Background

Thoracic Endovascular Aortic Repair (TEVAR) has substantially decreased the mortality and major complications from aortic surgery. However, neurological complications such as spinal cord ischemia may still occur after TEVAR. S-100β is a biomarker of central nervous system injury, and oxidant injury plays an important role in neurological injury. In this pilot study, we examined the trends of S-100β and antioxidant capacity in the CSF during and after TEVAR.

Methods

We recruited 10 patients who underwent elective TEVAR. CSF samples were collected through a lumbar catheter at the following time points: before the start of surgery (T0) and immediately (T1) and 24 (T2) and 48 hours (T3) after the deployment of the aortic stent. S-100β and CSF antioxidant capacity were analyzed with the use of commercially available kits.

Results

We observed that the level of S-100β in all of the subjects at 24 hours after the deployment of the aortic stent (T2) increased. However, the levels of S-100β at T1 and T3 were comparable to the baseline value. The antioxidant capacity remained unchanged. No patient had a clinical neurologic complication.

Conclusions

Our observations may indicate biochemical/subclinical central nervous system injury attributable to the deployment of the aortic stent.