Abstract
To examine whether machine learning (ML) approach can be used to predict hematoma expansion in acute intracerebral hemorrhage (ICH) with accuracy and widespread applicability, we applied ML ...algorithms to multicenter clinical data and CT findings on admission. Patients with acute ICH from three hospitals (n = 351) and those from another hospital (n = 71) were retrospectively assigned to the development and validation cohorts, respectively. To develop ML predictive models, the k-nearest neighbors (k-NN) algorithm, logistic regression, support vector machines (SVMs), random forests, and XGBoost were applied to the patient data in the development cohort. The models were evaluated for their performance on the patient data in the validation cohort, which was compared with previous scoring methods, the BAT, BRAIN, and 9-point scores. The k-NN algorithm achieved the highest area under the receiver operating characteristic curve (AUC) of 0.790 among all ML models, and the sensitivity, specificity, and accuracy were 0.846, 0.733, and 0.775, respectively. The BRAIN score achieved the highest AUC of 0.676 among all previous scoring methods, which was lower than the k-NN algorithm (p = 0.016). We developed and validated ML predictive models of hematoma expansion in acute ICH. The models demonstrated good predictive ability, showing better performance than the previous scoring methods.
The anomalous Hall effect (AHE) that emerges in antiferromagnetic metals shows intriguing physics and offers numerous potential applications. Magnets with a rutile crystal structure have recently ...received attention as a possible platform for a collinear-antiferromagnetism-induced AHE. RuO
is a prototypical candidate material, however the AHE is prohibited at zero field by symmetry because of the high-symmetry 001 direction of the Néel vector at the ground state. Here, we show AHE at zero field in Cr-doped rutile, Ru
Cr
O
. The magnetization, transport and density functional theory calculations indicate that appropriate doping of Cr at Ru sites reconstructs the collinear antiferromagnetism in RuO
, resulting in a rotation of the Néel vector from 001 to 110 while maintaining a collinear antiferromagnetic state. The AHE with vanishing net moment in the Ru
Cr
O
exhibits an orientation dependence consistent with the 110-oriented Hall vector. These results demonstrate that material engineering by doping is a useful approach to manipulate AHE in antiferromagnetic metals.
Prolonged seizures status epilepticus (SE) constitute a neurological emergency that can permanently damage the brain. SE results from a failure of the normal mechanisms to terminate seizures; in ...particular, γ‐amino butyric acid‐mediated inhibition, and benzodiazepine anticonvulsants are often incompletely effective. ATP acts as a fast neurotransmitter via ionotropic ligandgated P2X receptors. Here we report that SE induced by intra‐amygdala kainic acid in mice selectively increased hippocampal levels of P2X7 receptors relative to other P2X receptors. Using transgenic P2X7 reporter mice expressing enhanced green fluorescent protein, we identify dentate granule neurons as the major cell population transcribing the P2X7 receptor after SE. Pretreatment of mice with an intracerebroventricular microinjection of 1.75 nmol A438079, a P2X7 receptor antagonist, reduced seizure duration by 58% and reduced seizure‐induced neuronal death by 61%. Injection of brilliant blue G (1 pmol), another selective antagonist, reduced seizure duration by 48% and was also neuroprotective. A438079 was seizure‐suppressive when injected shortly after induction of SE, and coinjection of A438079 with lorazepam 60 min after triggering SE, when electrographic seizure‐responsiveness to lorazepam had decreased, also terminated SE. Our results suggest that P2X7 receptor antagonists may be a promising class of drug for seizure abrogation and neuroprotection in SE.—Engel, T., Gomez‐Villafuertes, R., Tanaka, K., Mesuret, G., Sanz‐Rodriguez, A., Garcia‐Huerta, P., Miras‐Portugal, M. T., Henshall, D. C., Diaz‐Hernandez, M. Seizure suppression and neuroprotection by targeting the purinergic P2X7 receptor during status epilepticus in mice. FASEB J. 26, 1616‐1628 (2012). www.fasebj.org
Summary
Purpose
ATP is an essential transmitter/cotransmitter in neuron function and pathophysiology and has recently emerged as a potential contributor to prolonged seizures (status epilepticus) ...through the activation of the purinergic ionotropic P2X7 receptor (P2X7R). Increased P2X7R expression has been reported in the hippocampus, and P2X7R antagonists reduced seizure‐induced damage to this brain region. However, status epilepticus also produces damage to the neocortex. The present study was designed to characterize P2X7R in the neocortex and assess effects of P2X7R antagonists on cortical injury after status epilepticus.
Methods
Status epilepticus was induced in mice by intraamygdala microinjection of kainic acid. Specific P2X7R inhibitors were administered into the ventricle before seizure induction, and cortical electroencephalography and behavior was recorded to assess seizure severity. P2X7R expression was examined in neocortex up to 24 h after status epilepticus, in epileptic mice, and in resected neocortex from patients with pharmacoresistent temporal lobe epilepsy (TLE). In addition, the induction of P2X7R after status epilepticus was investigated using transgenic P2X7R reporter mice, which express enhanced green fluorescent protein under the control of the p2x7r promoter.
Key Findings
Status epilepticus resulted in increased P2X7R protein levels in the neocortex of mice. Neocortical P2X7 receptor levels were also elevated in mice that developed epilepsy after status epilepticus and in resected neocortex from patients with pharmacoresistent TLE. Immunohistochemistry determined that neurons were the major cell population transcribing the P2X7R in the neocortex within the first 8 h after status epilepticus, whereas in epileptic mice, P2X7R up‐regulation occurred in microglia as well as in neurons. Pretreatment of mice with the specific P2X7R inhibitor A‐438079 reduced electrographic and clinical seizure severity during status epilepticus and reduced seizure‐induced neuronal death in the neocortex.
Significance
Our findings identify neurons in the neocortex as an important site of P2X7R up‐regulation after status epilepticus and in epilepsy, and provide support for the possible use of P2X7R antagonists for the treatment of status epilepticus and prevention of seizure‐induced brain damage.
Pegfilgrastim dramatically reduces febrile neutropenia (FN) caused by high-risk chemotherapy. This report details the presentation of a 72-year-old female who developed a fatal infection of ...Pseudomonas aeruginosa pneumonia that occurred during preoperative chemotherapy despite pegfilgrastim administration. She was brought to the hospital with symptoms of high fever and general fatigue during chemotherapy, but her respiratory symptoms were minimal, and a chest computed tomography (CT) showed no obvious signs of pneumonia. She had FN. After she was hospitalized, her breathing and consciousness worsened rapidly, and the chest CT showed prominent lobar pneumonia. Her blood cultures suggested P. aeruginosa, so she was quickly switched to meropenem. She was diagnosed with septic shock and acute respiratory distress syndrome due to severe P. aeruginosa pneumonia, and she was started on noninvasive positive pressure ventilation with immunoglobulin preparations. P. aeruginosa developed drug resistance, so it was necessary to change antibiotics. She was discharged without complications of pulmonary fibrosis on chest CT. It is crucial to always be aware that severe infections can occur even with pegfilgrastim administration, promptly identify the causative pathogen, and intervene with early treatment.
Apelin, the endogenous ligand of the APJ receptor, has been identified in a variety of tissues, including stomach, heart, skeletal muscle, and white adipose tissue. We sought to clarify the effects ...of apelin on body adiposity and the expression of uncoupling proteins (UCPs) in C57BL/6 mice. Treatment with ip apelin at a dose of 0.1 μmol/kg·d for 14 d decreased the weight of white adipose tissue and serum levels of insulin and triglycerides, compared with controls, without influencing food intake. Apelin treatment also decreased body adiposity and serum levels of insulin and triglycerides in obese mice fed a high-fat diet. Apelin increased the serum adiponectin level and decreased that of leptin. Additionally, apelin treatment increased mRNA expression of UCP1, a marker of peripheral energy expenditure, in brown adipose tissue (BAT) and of UCP3, a regulator of fatty acid export, in skeletal muscle. In addition, immunoblot bands and relative densities of UCP1 content in BAT were also higher in the apelin group than controls. Furthermore, apelin treatment increased body temperature and O2 consumption and decreased the respiratory quotient. In conclusion, apelin appears to regulate adiposity and lipid metabolism in both lean and obese mice. In addition, apelin regulates insulin resistance by influencing the circulating adiponectin level, the expression of BAT UCP1, and energy expenditure in mice.
Purpose
The authors recently proposed the novel radiologic assessment method to measure chronological screw position changes precisely. The aim of this study was to predict the late occurrence of ...screw loosening, which was diagnosed by the radiographic lucent zone, by evaluating screw position changes at an early postoperative stage using the novel method.
Methods
Forty-three patients who underwent thoracolumbar screw fixation and follow-up computed tomography (CT) scans on the day, between 1 and 5 weeks, and at more than 6 months after surgery were retrospectively evaluated. Screw images were generated from CT data. Screw position changes were evaluated by superposing screw images on the day and between 1 and 5 weeks after surgery. Screw loosening was diagnosed by the radiographic lucent zone on CT images at 6 months or later post-surgery, and patients were classified into screw loosening and non-loosening groups. The early screw position changes were compared between the two groups.
Results
Significant differences in early screw position changes were found between the screw loosening and non-loosening groups in Mann–Whitney
U
test (
p
= 0.001). On the receiver operating characteristic (ROC) curve analysis, the area under the ROC curve was 0.791, and the best cutoff value of early screw position change for the prediction of screw loosening was 0.83 mm with a sensitivity of 64.0% and a specificity of 88.9%.
Conclusion
We calculated a cutoff value of the screw position changes at an early postoperative stage for the prediction of subsequent development of screw loosening with the radiographic lucent zone.
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