Raindrop size distribution (DSD) characteristics within the complex area of Busan, Republic of Korea (35.12° N, 129.10° E), were studied using a Precipitation Occurrence Sensor System (POSS) ...disdrometer over a 4-year period from 24 February 2001 to 24 December 2004. Also, to find the dominant characteristics of polarized radar parameters, which are differential radar reflectivity (Zdr), specific differential phase (Kdp) and specific attenuation (Ah), T-matrix scattering simulation was applied in the present study. To analyze the climatological DSD characteristics in more detail, the entire period of recorded rainfall was divided into 10 categories not only covering different temporal and spatial scales, but also different rainfall types. When only convective rainfall was considered, mean values of mass-weighted mean diameter (Dm) and normalized number concentration (Nw) values for all these categories converged around a maritime cluster, except for rainfall associated with typhoons. The convective rainfall of a typhoon showed much smaller Dm and larger Nw compared with the other rainfall categories. In terms of diurnal DSD variability, we analyzed maritime (continental) precipitation during the daytime (DT) (nighttime, NT), which likely results from sea (land) wind identified through wind direction analysis. These features also appeared in the seasonal diurnal distribution. The DT and NT probability density function (PDF) during the summer was similar to the PDF of the entire study period. However, the DT and NT PDF during the winter season displayed an inverse distribution due to seasonal differences in wind direction.
We aimed to evaluate the long-term clinical outcomes and prognostic factors of symptomatic intracranial unruptured vertebrobasilar artery dissection (siu-VBD).
A total of 191 patients (M:F = 127:64; ...median age, 46 years) with siu-VBD were treated between January 2001 and December 2008. Presentations, treatments, outcomes, and prognostic factors were retrospectively analyzed.
Clinical manifestations were ischemic symptoms with headache (n = 97) or without headache (n = 13) and headache without ischemic symptoms (n = 81). Forty-six patients (24.1%) underwent endovascular treatment. The remaining 145 patients (75.9%) were medically treated with anticoagulants (n = 49), antiplatelets (n = 48), or analgesics alone (n = 48). Clinical follow-up data were available in 178 patients (102 ischemic and 76 nonischemic) at 15 to 102 months (mean, 46 months). None of the siu-VBD hemorrhaged. All 76 patients without ischemic presentation had favorable outcomes (modified Rankin Scale, 0-1). Of the 102 patients with ischemic presentation, outcomes were favorable in 92 and unfavorable in 10 patients. Four patients died; 3 died of causes unrelated to VBD, and one died as a result of basilar artery (BA) dissection. Old age (odds ratio OR 1.099; 95% confidence interval CI 1.103-1.204; p = 0.042) and BA involvement (OR 11.886; 95% CI 1.416-99.794; p = 0.023) were independent predictors of unfavorable outcomes in siu-VBD with ischemic presentation.
Clinical outcomes for siu-VBD were favorable in all patients without ischemic symptoms and in most patients with ischemic presentation. None of the siu-VBD caused subarachnoid hemorrhage. Old age and BA involvement were independent predictors of unfavorable outcome in siu-VBD with ischemic presentation.
Background
Periostin is a matricellular protein, and its synthesis in airway epithelial cells and lung fibroblasts is induced by interleukin (IL)‐4 and IL‐13. The significance of periostin as a ...biomarker of TH2‐induced airway inflammation, and (importantly) as a measure of the response to TH2‐targeted therapy, has recently been emphasized. We explored the relationship between periostin and airway hyperresponsiveness (AHR) in asthmatic children.
Methods
The study included 83 children aged 6–15 years in an asthmatic group (n = 54) and healthy controls (n = 29). We measured the periostin levels in serum and performed methacholine and mannitol provocation challenges. The responses to mannitol were expressed as the provocative dose causing a 15% fall in the FEV1 (the PD15 dose).
Results
Of the 54 subjects with asthma, all had positive methacholine bronchial provocation test (BPT) results and 38 had positive mannitol BPT results. Children with asthma had significantly higher periostin levels than controls 76.0 (65.0–91.8) vs 71.0 (57.5–80.0) ng/mL; P = 0.017. Periostin levels were significantly correlated with both the methacholine PC20 and mannitol PD15 values.
Conclusion
Serum levels of periostin, a new biomarker induced by IL‐13, were higher in asthmatic children, and were associated with AHR to methacholine and mannitol.
Little has been known about the clinical and angiographic follow-up results of stent-only therapy for intracranial vertebrobasilar dissecting aneurysms (VBDA). The purpose of this study was to ...evaluate the feasibility, safety, clinical, and angiographic follow-up of stent-only therapy for VBDA.
Twenty-seven patients with 29 VBDAs (11 ruptured, 18 unruptured), not suitable for deconstructive treatment, underwent stent-only therapy. Feasibility, safety, clinical, and angiographic follow-up were retrospectively evaluated. Angiographic outcomes were compared between single-stent and multiple-stent groups.
All attempted stent placements were successfully accomplished without any treatment-related complication. Of the 11 ruptured VBDAs, 4 were treated by single stents, 6 by double overlapping stents, and 1 by triple overlapping stents. Of the 18 unruptured VBDAs, 6 were treated by stents, and 12 by double overlapping stents. One patient with a ruptured VBDA, treated by single stent, had rebleeding and died. None of the remaining patients had posttreatment bleeding during follow-up (mean, 28 months; range, 7-50 months). Eight patients with ruptured VBDA and all patients with unruptured VBDA had excellent outcomes (modified Rankin Scale, 0-1). The remaining 2 patients with ruptured VBDA were moderately disabled because of the initial damage. Angiographic follow-up was available in 27 VBDAs, 4 to 42 months (mean, 12 months) after treatment. Follow-up angiograms revealed complete obliteration of the dissecting aneurysm in 12, partial obliteration in 12, stable in 1, enlargement in 1, and in-stent occlusion in 1. Angiographic improvement (complete or partial obliteration) was more frequent in the multiple-stent group (17/17) than in the single-stent group (7/9; P < .05).
In this small series, stent-only therapy was safe and effective in the treatment of VBDAs that were not deemed suitable for treatment with parent-artery occlusion.
To describe the results of transvenous embolizations of cavernous dural arteriovenous fistua (cDAVF) with an emphasis on identifying the incidence, characteristics, and management strategies ...associated with the complications of transvenous embolization of cDAVFs.
Fifty-six consecutive patients who were treated by transvenous embolization for cDAVFs were reviewed. The approach routes, angiographic results, complications, and clinical outcome were assessed.
Retrograde inferior petrosal sinus (n = 36), transfacial vein (n = 7), transcontralateral intercavernous sinus (n = 4), and direct superior ophthalmic vein (n = 3) approaches were used. Angiographic results showed complete occlusion (n = 29), nearly complete occlusion (n = 13), and incomplete occlusion (n = 14). Complications associated with the procedures were cranial nerve palsy (n = 6), venous perforation (n = 3), and brain stem congestion (n = 2). The cranial nerve signs resolved with conservative treatment. Venous perforations were managed by coil embolizations at the site of the tear with no significant neurologic sequelae. One case of brain stem congestion resulted in hemiplegia after conservative treatment. The other case showed venous congestion as a result of rerouting of the shunted flow after venous embolization that was successfully managed by covered stent deployment for occlusion of the residual feeders. Clinical follow-up data were available in 46 patients. Complete resolution or improvement of symptoms was seen in 42 patients (91%).
Cavernous DAVFs may be effectively treated by transvenous embolization. However, the procedure can be associated with various complications, some of which can potentially result in significant morbidity. Prompt diagnosis of the complications with appropriate management strategies is mandatory for a safe procedure.
Fusiform aneurysms and ultrawide-neck circumferential aneurysms are still some of the most challenging lesions. The aim of this study was to investigate the efficacy and feasibility of the use of ...multiple overlapping Enterprise stents with coiling for the treatment of fusiform or ultrawide-neck circumferential aneurysms.
Twelve consecutive patients (9 men and 3 women; mean age, 56 years) with fusiform (n = 5) or ultrawide-neck circumferential (n = 7) aneurysms were treated with 2-3 overlapping Enterprise stents and coiling. The feasibility of this procedure and the clinical and angiographic outcomes of this technique were retrospectively evaluated.
All patients were successfully treated by using this technique without any complications. Posttreatment angiographic results revealed grade 4 occlusion of the aneurysm in 6, grade 3 in 4, and grade 2 in 2 patients. Clinical follow-up was performed in all patients (mean, 16 months; range, 5-24 months). Nine patients had an mRS score of 0. Two had an mRS score of 1, one of whom had an initial mRS score of 2 due to the mass effect of a giant aneurysm; the other had a recurrent aneurysm presenting with SAH 5 years after clipping. Angiographic follow-up was performed in 10 patients at 6-20 months posttreatment. Nine had stable or improved occlusion, while 1 had a minor recurrence.
In this small series, multiple overlapping Enterprise stents with coiling were a feasible and effective option for the treatment of fusiform and ultrawide-neck circumferential aneurysms. Further experience and follow-up are required to document the long-term efficacy of this treatment.
To maximize dye absorption and improve energy conversion efficiency, we adopted a branched structure for single crystalline ZnO nanowires in dye-sensitized solar cells (DSSCs). The ZnO nanowire DSSCs ...exhibited an overall efficiency of ∼0.46%.
To maximize dye absorption and improve energy conversion efficiency, we adopted a branched structure for single crystalline ZnO nanowires in dye-sensitized solar cells (DSSCs). The high-density branched structures of these ZnO nanowires were incorporated by a two-step seeding with zinc acetate dihydrate seeds. The ZnO nanowire DSSCs exhibited an overall efficiency of ∼0.46%. This represented a 35% improvement compared to the ZnO nanowire DSSCs with pillar-shaped ZnO nanowires. Our current density–voltage (J–V) characterizations suggest that the current densities and power conversion efficiencies were improved by increasing the surface area with these branched structures of ZnO nanowires in DSSCs.
Although multiple intracranial aneurysms are frequent, determining treatment strategy and methods for them is often complicated. The aim of this study was to evaluate the safety and effectiveness of ...1-stage coiling for multiple intracranial aneurysms.
All patients who underwent 1-stage coiling for ≥2 aneurysms were identified from a prospectively registered neurointerventional data base during 10 years. The patient characteristics and clinical and angiographic outcomes at discharge and follow-up were retrospectively evaluated.
One hundred sixty-seven patients (male/female ratio, 30:137; mean age, 58 years) with multiple aneurysms (418 aneurysms; mean, 2.5 aneurysms/patient) underwent attempted 1-stage coiling for ≥2 aneurysms (359 aneurysms; mean, 2.1 aneurysms/patient). In 131 patients (78.4%), all detected aneurysms were treated with coiling only. Treatment-related morbidity and mortality at discharge were 1.8% and 0.6% per patient, respectively. Of the 132 patients without subarachnoid hemorrhage, 129 (97.7%) had favorable outcomes (mRS 0-2) at discharge; of the 35 patients with SAH, 27 (77.1%) had favorable outcomes at discharge. Of the 162 patients (97%) for whom clinical follow-up was available (mean, 35.8 months), 154 patients (95.1%) had favorable outcomes. Immediate posttreatment angiography showed complete occlusion in 186 (51.8%) aneurysms, neck remnants in 134 (37.3%), sac remnants in 33 (9.2%), and failure in 6 (1.7%). Of the 262 (73.9%) aneurysms that underwent follow-up imaging (mean, 24.8 months), 244 (93.1%) showed a stable or improved state, with 12 (4.6%) minor and 6 (2.3%) major recurrences.
One-stage coiling of multiple aneurysms seems to be safe and effective, with low morbidity and mortality.
Thin-section noncontrast CT (NCT) can detect thrombi in large arteries and can provide a measure of thrombus composition based on Hounsfield Units (HU). A study using polyethylene tubes as a model of ...intracranial arteries concluded that the HUs of platelet-rich thrombi are lower than those of erythrocyte-rich thrombi. Thrombus HUs were measured by NCT in 34 patients with acute ischemic stroke before thrombolysis. Thrombi with lower HU counts were resistant to thrombolytics.
AICA aneurysms are rare and a challenge to treat surgically. We present our experience of the angiographic results and the clinical outcomes for 9 AICA aneurysms treated by EVT.
Between 1997 and ...2009, EVT was attempted for 9 AICA aneurysms. Six patients presented with SAH, and 3 aneurysms were found incidentally. The location of the aneurysms was the proximal AICA in 7 and the distal AICA in 2. Five aneurysms originated from an AICA-PICA variant. Clinical outcomes and procedural complications were evaluated, and angiography was performed 6, 12, and 24 months after embolization to confirm recanalization of the coiled aneurysm.
EVT was technically successful in 7 patients (78%). Surgical trapping was performed in 1 patient after failure of EVT, and another aneurysm occluded spontaneously, along with the parent artery during EVT. In 7 patients, the AICAs had good patency on postoperative angiography. Stent-assisted coiling was performed in 3 patients. Follow-up angiographies were performed in 7 patients and showed no evidence of recanalization or progressive occlusion with further thrombosis except in 1 patient. There was no evidence of aneurysm rupture during the follow-up period, and 8 patients were able to perform all usual activities (mRS score, 0-1).
EVT may provide a feasible and safe option as an alternative, though a microsurgical option is initially considered for the management of AICA aneurysms. Further follow-up and more experience are also necessary.