Precise control of the size and structure is one critical design parameter of micellar systems for drug delivery applications. To control the size of self-aggregates, chitosan was depolymerized with various amounts of sodium nitrite, and hydrophobically modified with deoxycholic acid to form self-aggregates in aqueous media. Formation and physicochemical characteristics of size-controlled self-aggregates were investigated using dynamic light scattering, fluorescence spectroscopy, and computer simulation method. The size of self-aggregates varied in the range of 130-300 nm in diameter, and their structures were found to depend strongly on the molecular weight of chitosan ranging from 5 to 200 kDa. Due to the chain rigidity of chitosan molecule, the structure of self-aggregates was suggested to be a cylindrical bamboolike structure when the molecular weight of chitosan was larger than 40 kDa, which might form a very poor spherical form of a birdnestlike structure. To explore the potential applications of self-aggregates as a gene delivery carrier, complexes between chitosan self-aggregates and plasmid DNA were prepared and confirmed by measuring the fluorescence intensity of ethidium bromide and electrophoresis on agarose gels. The complex formation had strong dependency on the size and structure of chitosan self-aggregates and significantly influenced the transfection efficiency of COS-1 cells (up to a factor of 10). This approach to control the size and structure of chitosan-derived self-aggregates may find a wide range of applications in gene delivery as well as general drug delivery applications.

BTX-A may provide better AR symptom relief in terms of duration and degree than a steroid injection.

NPT with AR could be a useful tool for the differential diagnosis of allergic, nonallergic, and local allergic rhinitis.

Evaluation of the nasal bone and nasal pyramid is essential for the correct osteotomy. The shape of the nasal bone and nasal pyramid of Korean subjects were analyzed using a three-dimensional computed tomography (CT). This study includes 75 patients who visited Inha University Hospital and got a three-dimensional CT from October 2005 to June 2006 (58 males, 17 females, mean age of 33.1 years). The thickness of the bone at the nasomaxillary suture as well as between the rhinion and nasomaxillary suture, on which a lateral osteotomy was performed, was measured. In addition, the length of the nasal bone and the width of pyriform aperture were measured. The morphology of the nasal bone was classified from A to E type, according to Hwang's method. The subjects included 58 males and 17 females with a mean age of 33.1 years. The mean thickness of the lateral osteotomy point is 2.03+/-0.35 mm and that of the medial osteotomy point is 1.75+/-0.37 mm. The mean length of the nasal bone is 20.95+/-5.99 mm. The number of patients with a long nasal bone (more than 25 mm) is 14.7% (11/75). The most common morphology of the nasal bone is A type and there is no D or E type. Since there is no significant difference in the thickness of the nasal bone at the lateral and intermediate osteotomy point, the same strength should be used to perform the correct lateral and intermediate osteotomy. However, the actual lateral osteotomy is performed at a more lateral position than the nasomaxillary suture, which is our standard of measurement. So, using more power in the lateral osteotomy should be considered. There were nine patients with a long nasal bone in this study. For these patients, better results with percutaneous transverse osteotomy could be expected.

ObjectivesVidian neurectomy could be considered the treatment of choice for intractable rhinitis, because it is the only method that can permanently block the pathophysiological mechanism of rhinitis. The goal of this study was to evaluate the effect of vidian neurectomy on nasal symptoms and tear production, and to assess for possible complications.MethodsSix patients with intractable rhinitis who underwent endoscopic transnasal vidian neurectomy were enrolled. The degree of symptom improvement and complications were assessed through retrospective review of medical records prior to, and 1 year following surgery, and telephone survey after 6.9±2.1 years. Schirmer's test was performed before surgery, and these values were compared to postoperative results at 1 day, 1 month, and 2 months.ResultsChanges in the visual analogue scale were significant in nasal obstruction (8.5±2.5 to 3.0±2.0, P<0.05) and rhinorrhea (9.0±2.2 to 2.0±1.6, P<0.05). Improvements persisted for up to 7 years after the primary surgery. Patients complained of mild dry eyes for 1 month after vidian neurectomy. However, five out of six reported marked improvement of xerophthalmia after 2 months. Aside from mild crusting of the nasal cavity and mild postoperative pain, there were no major complications. During the entire follow-up period, no patient needed additional treatment, such as antihistamines or corticosteroids.ConclusionVidian neurectomy is effective in alleviating nasal symptoms in patients with intractable rhinitis refractory to other treatments. This effect is sustained for at least 7 years with minimal postoperative complications.

The nasal provocation test can be helpful in evaluating the severity of allergic rhinitis. However, we must be careful in interpreting the results alone.

Objectives There is a great deal of interest in the possibility that environmental factors may influence the risk of developing allergic rhinitis (AR) in early life. We investigated the simultaneous effects of mode of delivery and duration of breastfeeding on the development of AR in children. Methods Data from 1,374 children participating in the Allergic Rhinitis Cohort Study for kids (ARCO-kids study) was analyzed. All subjects were divided into AR or non-allergic rhinitis (NAR) groups. Data on environmental factors, mode of delivery and duration of breastfeeding were collected using a questionnaire. Results Compared with short-term breastfeeding (<6 months), long-term breastfeeding (≥12 months) was significantly associated with a lower prevalence of AR (adjusted odds ratio [aOR], 0.54; 95% confidence interval [CI], 0.34 to 0.88). Children in the AR group also had a higher cesarean delivery rate than those in the NAR group (39.1% vs. 32.8%, P =0.05). Regarding the combined effects of mode of delivery and duration of breastfeeding, long-term breastfeeding with a vaginal delivery strongly suppressed the development of AR, compared to short-term breastfeeding with a cesarean delivery (aOR, 0.47; 95% CI, 0.30 to 0.73). Conclusion Long-term breastfeeding (≥12 months) and a vaginal delivery are associated with a lower risk of developing childhood AR.

Fourteen of 131 patients (10.7%) had recurrent VN. The subjective intensity of recurrent VN was less than the first attack. There were no significant differences in clinical characteristics such as accompanying headache or preceding respiratory infection and in epidemiologic risk factors between patients with recurrent and non-recurrent VN. Twenty of 131 patients (15.3%) experienced BPPV during the follow-up period.