ABSTRACT The dielectric breakdown of an unpoled piezoelectric ceramic, PZT807, with a conductive channel, is investigated. Cylindrical bar specimens with a conductive channel are used for breakdown tests of the unpoled piezoelectric ceramic under purely electrical loads. Narrow tubular channels emanating from the head of the initial channel are observed in the specimens after breakdown occurs. The radius of the tubular channel that is created at the surface of the initial channel head is insensitive to various types of channel formation. The problem of a fine tubular channel that emanates from the initial channel head is numerically solved to evaluate the three‐dimensional J integral, which is directly related to the energy that is available at breakdown, at the initiation of a new channel in the specimen. The critical J integral at the onset of breakdown is obtained.
OBJECTIVE There are few studies on the ischemic necrosis and apoptosis of septal cartilage after using bilateral spreader grafts in rhinoplasty. We attempted to evaluate structural changes to the septal cartilage after using the bilateral spreader graft and herein propose possible involved mechanisms observed by histopathologic examination, the apoptosis index using the TUNEL assay, and ultrastructural examination using an electron microscope. METHODS Septal cartilage between bilateral spreader grafts (group A, n = 12), cartilage beside unilateral spreader grafts (group B, n = 12), and normal septal cartilage (group C, n = 12) were obtained from 36 patients who had revision rhinoplasty because of minor cosmetic dissatisfaction. MAIN OUTCOME MEASURES We investigated the histopathologic appearance via hematoxylin-eosin staining. Then, using the TUNEL assay, we determined the apoptosis index. Finally, we studied cell morphology under a transmission electron microscope. RESULTS Although the thickness of septal cartilage was not significantly different between groups, the signs of ischemic necrosis were more prominent in group A. The apoptosis index was significantly higher in group A than in group B or C (p < .05). We observed evidence of cellular injury also by electron microscope examination. CONCLUSIONS The survival of septal cartilage could be affected by bilateral spreader grafts through the mechanism of ischemic necrosis and apoptosis.
Objective The authors aimed to (1) compare symptom changes in patients with or without nonspecific hyperreactivity, (2) compare changes in total nasal volume (TNV) and minimal cross‐sectional area (MCA) using acoustic rhinometry after cold dry air (CDA) challenge, and (3) set the diagnostic criteria using receiver operating characteristic (ROC) curve analysis. Study Design Prospective pilot. Setting Academic tertiary rhinologic practice. Subjects and Methods CDA provocation was performed on 45 patients with self‐reported hypersensitivity to cold dry air (group A) and to 53 patients without such hypersensitivity (group B). Symptoms (as measured by visual analog scale [VAS]), TNV, and MCA were checked before and after provocation. Results The changes in nasal obstruction (1.8 ± 2.1 vs 0.0 ± 2.3) and rhinorrhea (0.8 ± 2.1 vs −0.5 ± 2.3) were significantly greater in group A ( P <. 01 in each case). There were no significant differences between groups in VAS scores for sneezing and itching. From the ROC curve, the authors set the diagnostic criterion as “TNSS (total nasal symptom score) change larger than 1.5,” and its sensitivity and specificity were 75.6% and 86.8%, respectively. The criteria “TNV decrease larger than 19.5%” and “MCA change larger than 15.0%” had higher sensitivity and specificity (TNV: 84.4% sensitivity and 77.4% specificity; MCA: 93.3% sensitivity and 77.4% specificity). Conclusions The authors were able to propose diagnostic criteria of nonspecific hyperreactivity using a CDA provocation test with acoustic rhinometry. These results are also helpful for understanding the pathophysiologic mechanisms of nonspecific hyperreactivity.
Background and Objectives: We aimed to provide an updated data on the prevalence of allergic rhinitis (AR) in the Korean population and to evaluate the correlation between AR and hypertension, obesity, and smoking. Materials and Methods: Analysis of data from 31,822 people in Korean National Health and Nutrition Examination Survey during a 5-year period (from 2010 to 2014). The diagnosis of AR was done by questionnaire. Results: The overall prevalence of AR was 15.2% and 16.4% in Korean males and females, respectively. The prevalence tended to decrease with age. Subjects with AR were younger than those without (p<0.001) in both males and females. Living in urban area, history of atopic dermatitis, and asthma were all significantly correlated with higher prevalence (p<0.01). Risk for AR conferred to maternal hypertension history was 1.31 (95% CI=1.06-1.62 ; p<0.05) in the male population. However, systolic and diastolic blood pressures (DBP), medication history, and paternal hypertension history did not differ between the AR and normal groups (p>0.05). The odds ratio of obesity (BMI ≥25, compared to normal) for AR was 0.82 (95% CI=0.68-0.98 ; p<0.05) in the male population. Finally, the adjusted odds ratio of ex-smoker (compared to non-smoker) for AR was 1.41 (95% CI=1.05-1.89 ; p<0.05) in males. However, current smoking and pack-year did not differ between AR and normal groups (p>0.05). Conclusions: There was no significant correlation between hypertension and AR. In Korean adult males, obesity was associated with a low prevalence of allergic rhinitis. Although there was no significant correlation between current smoking and AR, there was a notable correlation between ex-smoking and AR in male adults. (J Clinical Otolaryngol 2018;29:42-52)
Nasal route drug administration for local and systemic delivery of many therapeutics has received attention because the nasal cavity is highly vascularized and provides a large surface area for drug absorption. However, nasal mucosa exhibits limited permeability to polar molecules. In this study, we developed a novel method for improving absorption efficiency of polar drugs by applying hypergravity. RPMI 2650 cells and primary human nasal epithelial cells were exposed three times to a 20 min hypergravitational condition (10 × g) with a 20 min rest period after each exposure. The applied hypergravity induced a decrease in transepithelial electrical resistance without significant loss of cellular metabolic activity, and cellular permeability of fluorescein sodium salt (MW 376 Da; NaFI) and FITC-labeled dextran (average MW 4,000 Da; FD-4) increased by 19% and 16%, respectively. Immunostaining and RT-qPCR results demonstrated that hypergravity conditions affected cytoskeletal structures and tight junctions, leading to weakening of the cell barrier function and increasing the cellular permeability of polar molecules. Our results indicate that hypergravity could be used as a new strategy for enhancing the efficiency of drug absorption via the nasal route.
Recent studies have reported that glucosamine (GlcN) showed therapeutic effects in allergic diseases such as asthma and rhinitis, and its mechanisms include the suppression of T helper type 2 immune responses and the nuclear factor-κB pathway.We aimed to investigate the effect of GlcN on atopic dermatitis (AD) in an animal model.Twenty-five BALB/c mice were divided into five groups (groups A~E). Group A was the phosphate-buffered saline (PBS)-treated group without AD induction. Group B was the PBS control group with AD induction. Groups C to E were the AD induction groups, which were treated with three different doses of GlcN (10 mg, 20 mg, and 40 mg, respectively). Histopathological examination was performed after GlcN administration. Interleukin (IL)-4, IL-13, and IL-17 cytokine levels were measured by enzyme-linked immunosorbent assay using skin biopsy specimens. Serum total immunoglobulin E (IgE) concentrations were measured before and after administration with GlcN or PBS.Clinical dermatitis scores decreased with increasing GlcN dose (p<0.001). Concentrations of tissue IL-13 and IL-17 decreased after GlcN administration (each group: p=0.002 and p<0.001, respectively), but the concentrations of tissue IL-4 did not show differences across groups. Serum IgE levels tended to be lower after GlcN administration (p=0.004). Histopathological scores were not significantly different among groups B~E (p=0.394).GlcN improved AD symptoms and decreased tissue IL-13, IL-17, and serum total IgE levels in an animal model.
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
The AUA symptom index is widely used to access patients with suspected benign prostatic hyperplasia (BPH). In order to determine how well symptoms as assessed by this index correlate with urodynamic findings, we evaluated 83 patients referred to our urology clinics with symptoms of BPH. All patients completed the AUA symptom index and then underwent a multichannel urodynamic evaluation. Patients were classified as obstructed, unobstructed, or equivocal according to the Abrams Griffiths nomogram. The AUA symptom index was recorded as the total score and, for purposes of symptom classification, further subdivided into an obstructive score (questions 3, 5, and 6) and an irritative score (questions 1, 2, 4, and 7). The mean age of the 83 patients was 67 (45-84). The mean total AUA symptom score was 16.6 (6-34), mean obstructive score was 6.1 (0-15), and the mean irritative score 10.4 (3-20). Pressure flow analysis using the Abrams-Griffiths nomogram classified 28 patients (34%) as obstructed, 17 (20%) as unobstructed, and 38 (46%) as equivocal. Using the analysis of variance procedure (ANOVA) there was no statistically significant difference in the mean total (P = 0.446), obstructive (P = 0.979), or irritative (P = 0.136) scores. Detrusor instability was present in 45 patients (54%). While total and obstructive scores were not significantly different in patients with detrusor instability vs. those with stable bladders, irritative scores were higher in patients with instability (P = 0.028) using the T-test procedure. Using ANOVA, the difference in post void residual (PVR) between the groups was not quite statistically significant (P = 0.057).(ABSTRACT TRUNCATED AT 250 WORDS)
'%3e%3cg id='b'%3e%3cpath id='a' stroke='%23000' stroke-width='2' d='M-6-25H6m-12 3H6m-12 3H6'/%3e%3cuse xlink:href='%23a' y='44'/%3e%3c/g%3e%3cpath stroke='%23fff' d='M0 17v10'/%3e%3ccircle r='12' fill='%23cd2e3a'/%3e%3cpath fill='%230047a0' d='M0-12A6 6 0 0 0 0 0a6 6 0 0 1 0 12 12 12 0 0 1 0-24z'/%3e%3c/g%3e%3cg transform='rotate(-123.69)'%3e%3cuse xlink:href='%23b'/%3e%3cpath stroke='%23fff' d='M0-23.5v3M0 17v3.5m0 3v3'/%3e%3c/g%3e%3c/svg%3e)