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Automatic registration of unordered point clouds is the prerequisite for urban reconstruction. However, most of the existing technologies still suffer from some limitations. On one hand, most of them are sensitive to noise and repetitive structures, which makes them infeasible for the registration of large-scale point clouds. On the other hand, most of them dealing with point clouds with limited overlaps and unpredictable location. All these problems make it difficult for registration technology to obtain qualified results in outdoor point cloud. To overcome these limitations, this paper presents a grid graph-based point cloud registration (GGR) algorithm to align pairwise scans. First, point cloud is divided into a set of 3D grids. We propose a voting strategy to measure the similarity between two grids based on feature descriptor, transforming the superficial correspondence into 3D grid expression. Next, a graph matching is proposed to capture the spatial consistency from putative correspondences, and graph matching hierarchically refines the corresponding grids until obtaining point-to-point correspondences. Comprehensive experiments demonstrated that the proposed algorithm obtains good performance in terms of successful registration rate, rotation error, translation error, and outperformed the state-of-the-art approaches. [ABSTRACT FROM AUTHOR]

Abstract Background Both severe stenosis and completed occlusion in internal carotid artery or its distal branches have been considered the main reasons of cerebral hypoperfusion, which contributes to the washout disturbances of embolism in low perfusion territories distal to stenosis. An aggravated hypoperfusion state in certain brain region may induce ischemic stroke and further cognitive decline. However, the effective medication for cerebral hypoperfusion is largely unsettled. Methods/design By using computed tomography perfusion (CTP) imaging, the trial will evaluate the effectiveness, safety and tolerability of hydroxyethyl starch (HES) 130/0.4 for patients with extra-/intra-cranial artery stenosis and cerebral hypoperfusion. From 5 neurological inpatient wards, 300 patients will be randomly recruited for administered routine medications plus intravascular volume therapies using the equal volume of HES 130/0.4 or 0.9% sodium chloride solution. Cerebral hypoperfusion state after 7-day intervention is the primary outcome measure. The secondary outcome measures includes, impaired renal function, abnormal heart function, hematological changes, neurological dysfunctions and cerebrovascular events in peri-intervention period and/or 3-month follow-up. The sample size will allow the detection of a two-sided 5% significance level between groups in the endpoint with a power of 80%. Discussion The trial would provide important efficacy and safety data on the intravascular administration of HES 130/0.4 in patients with unilateral cerebral hypoperfusion. The effects on kidney function, heart function, coagulation, neurological function and cerebralvascular events will be assessed. Trial registration ClinicalTrials.gov (Identifier: NCT01192581)

Background: Transient ischemic attack (TIA) or minor ischemic stroke represents the largest group of cerebrovascular disease, and those patients have a high risk of early recurrent stroke. Over decades, anticoagulation therapy has been used prudently in them for likely increasing the risk of intra-/extra-cranial hemorrhagic complications. However, recently rivaroxaban, a new oral anticoagulant, is proved to be as effective as traditional anticoagulants, while carrying significantly less risk of intracranial hemorrhage. Therefore, we assumed that patients may benefit from rivaroxaban if treated soon after TIA or minor stroke, and designed this adequately powered randomized study, TRACE.Methods and Design: The Treatment of Rivaroxaban versus Aspirin in Non-disabling Cerebrovascular Events (TRACE) study is a randomized, double-blind clinical trial with a target enrollment of 4400 patients. A 14-days regimen of rivaroxaban 10 mg daily or a 14-days regimen of aspirin 100 mg daily will be administrated to randomized participants with acute TIA or minor stroke, defined as National Institute of Health Stroke Scale scores ≤ 3. The primary efficacy end point is percentage of patients with any stroke (ischemic or hemorrhage) at 14 days. Study visits will be performed at the day of randomization, day 14 and day 90.Discussion: Even though the new oral anticoagulants seem to be both safe and effective, few clinical trials have been carried out to test their effect on non-disabling cerebrovascular events. Treatment with rivaroxaban may prevent more cerebrovascular events with an acceptable risk profile after TIA or minor stroke, compared with aspirin, thus helping to improve the outcome of the disease.Trial Registration: No. NCT01923818. [ABSTRACT FROM AUTHOR]

Hand, foot and mouth disease (HFMD) was one of the most common infectious disease in the past few decades. After 2013, coxsackievirus A6 (CVA6) has replaced enterovirus 71 (EV-A71) and coxsackievirus A16 (CVA16), becoming the predominant pathogen responsible for HFMD in many areas in China. The objective of this study is to investigate the genetic characteristics and molecular epidemiology of CVA6 in Linyi from 2022 to 2023. A total of 965 HFMD cases were enrolled in this study and analyses based on VP1 nucleotide sequences were performed to determine the evolutionary trajectory of CVA6. In 2022, 281 (281/386, 72.8%) were positive for enterovirus (EVs), and 217 (217/281, 77.2%) were CVA6 positive. In 2023, 398 (398/579, 68.7%) samples were positive for EVs, and 243 (243/398, 61.1%) were CVA6 positive. Six sequences were selected from each year for the homology analysis. The results showed that 12 strains isolated in Linyi were far from the prototype strain (AY421764) and the first CVA6 strain reported in China (JQ364886). Phylogenetic analysis showed that the CVA6 strains isolated in Linyi all belonged to D3 subgenotype. CVA6 is emerging as a common pathogen causing HFMD in Linyi, and continuous surveillance of HFMD etiological agents is necessary.

Ginsenoside Rd (Rd), one of the main active ingredients in Panax ginseng, has been showed to protect against ischemic cerebral damage both in vitro and in vivo. However, the underlying mechanism of Rd is largely unknown. Excessive extracellular glutamate causes excitatory toxicity, leading to cell death, and neurodegenerative processes after brain ischemia. The clearance of extracellular glutamate by astrocytic glutamate transporter GLT-1 is essential for neuronal survival after stroke. Here we investigated the effects of Rd on the levels of extracellular glutamate and the expression of GLT-1 in vivo and in vitro. After rat middle cerebral artery occlusion, Rd significantly increased the mRNA and protein expression levels of GLT-1, and reduced the burst of glutamate as revealed by microdialysis. Consistently, specific glutamate uptake by cultured astrocytes was elevated after Rd exposure. Furthermore, we showed that Rd increased the levels of phosphorylated protein kinase B (PKB/Akt) and phospho-ERK1/2 (p-ERK1/2) in astrocyte culture after oxygen-glucose deprivation. Moreover, the effect of Rd on GLT-1 expression and glutamate uptake can be abolished by PI3K/AKT agonist LY294002 or ERK1/2 inhibitor PD98059. Taken together, our findings provide the first evidence that Rd can promote glutamate clearance by up-regulating GLT-1 expression through PI3K/AKT and ERK1/2 pathways.