Injection of SDF-1 loaded nanoparticles following traumatic brain injury stimulates neural stem cell recruitment.

Recruiting neural stem cell (NSC) at the lesion site is essential for central nervous system repair. This process could be triggered by the local delivery of the chemokine SDF-1. We compared two PLGA formulations for local brain SDF-1 delivery: SDF-1 loaded microspheres (MS) and SDF-1 loaded nanoparticles (NP). Both formulations were able to encapsulate more than 80% of SDF-1 but presented different release profiles, with 100% of SDF-1 released after 6days for the MS and with 25% of SDF-1 released after 2 weeks for NP. SDF-1 bioactivity was demonstrated by a chemotactic assay. When injected in mouse brain after traumatic brain injury, only SDF-1 nanoparticles induced NSC migration to the damage area. More neuroblasts (DCX+ cells) could be visualized around the lesions treated with NP SDF-1 compared to the other conditions. Rostral migratory stream destabilization with massive migration of DCX+ cell toward the perilesional area was observed 2 weeks after NP SDF-1 injection. Local injection of SDF-1-loaded nanoparticles induces recruitment of NSC and could be promising for brain injury lesion

Neuroprotective effect of heparin Trisulfated disaccharide on ischemic stroke

Cells undergoing hypoxia experience intense cytoplasmic calcium (Ca2+) overload. High concentrations of intracellular calcium ([Ca2+]i) can trigger cell death in the neural tissue, a hallmark of stroke. Neural Ca2+ homeostasis involves regulation by the Na+/Ca2+ exchanger (NCX). Previous data published by our group showed that a product of the enzymatic depolymerization of heparin by heparinase, the unsaturated trisulfated disaccharide (TD; ΔU, 2S-GlcNS, 6S), can accelerate Na+/Ca2+ exchange via NCX, in hepatocytes and aorta vascular smooth muscle cells. Thus, the objective of this work was to verify whether TD could act as a neuroprotective agent able to prevent neuronal cell death by reducing [Ca2+]i. Pretreatment of N2a cells with TD reduced [Ca2+]i rise induced by thapsigargin and increased cell viability under [Ca2+]I overload conditions and in hypoxia. Using a murine model of stroke, we observed that pretreatment with TD decreased cerebral infarct volume and cell death. However, when mice received KB-R7943, an NCX blocker, the neuroprotective effect of TD was abolished, strongly suggesting that this neuroprotection requires a functional NCX to happen. Thus, we propose TD-NCX as a new therapeutic axis for the prevention of neuronal death induced by [Ca2+]i overload

Neurological diagnoses in the emergency room: differences between younger and older patients

Neurological diseases are prevalent in the emergency room (ER). The aim of this study was to compare the neurological diagnoses between younger and older patients evaluated in the ER of a tertiary care hospital. METHOD: Patients admitted to the ER who required neurological evaluation in the first 24 hours were separated into two groups based on age, 50 years old. RESULTS: Cerebrovascular disease (59.6% vs. 21.8%, p50 years old group. Seizures (8.1% vs. 18.6%, p<0.01) and primary headache (3.7% vs. 11.4%, p<0.01) were most frequent in the <;50 years old group. CONCLUSION: The current study demonstrated that these three neurological diagnoses represented the majority of the neurological evaluations in the ER. National guidelines for ER teams that treat these prevalent disorders must be included in clinical practice and training

Curitiba acute ischemic stroke protocol: a university hospital and EMS initiative in a large Brazilian city

Few healthcare centers in Brazil perform thrombolytic therapy for acute ischemic stroke (AIS) patients. OBJECTIVE: The aim of this study was to describe an interinstitutional protocol for the rapid identification and thrombolytic treatment of AIS patients at a public health hospital in a large Brazilian city. METHOD: Emergency medical services (EMS) personnel evaluated 433 patients with possible stroke during a six-month period. After a standard checklist, patients with suspected AIS and symptoms onset of less than two hours were evaluated at our University Hospital (UH). RESULTS: Sixty-five (15%) patients met the checklist criteria and had a symptom onset of less than two hours, but only 50 (11%) patients were evaluated at the UH. Among them, 35 (70%) patients had ischemic stroke, 10 (20%) had hemorrhagic stroke, and 5 (10%) had other diagnoses. Of the 35 ischemic stroke patients, 15 (43%) underwent IV thrombolysis. CONCLUSION: The present study demonstrated that trained EMS workers could help to improve the rate of thrombolytic treatment in large Brazilian cities. Permanent training programs for EMS and hospital staff, with quality control and correct identification of AIS patients, should be implemented to increase appropriate thrombolytic therapy rates in Brazil