Relationship between Pericytes and Endothelial Cells in Retinal Neovascularization: A Histological and Immunofluorescent Study of Retinal Angiogenesis

PURPOSE: To evaluate the relationship between pericytes and endothelial cells in retinal neovascularization through histological and immunofluorescent studies. METHODS: C57BL/6J mice were exposed to hyperoxia from postnatal day (P) 7 to P12 and were returned to room air at P12 to induce a model of oxygen-induced retinopathy (OIR). The cross sections of enucleated eyes were processed with hematoxylin and eosin. Immunofluorescent staining of pericytes, endothelial cells, and N-cadherin was performed. Microfluidic devices were fabricated out of polydimethylsiloxane using soft lithography and replica molding. Human retinal microvascular endothelial cells, human brain microvascular endothelial cells, human umbilical vein endothelial cells and human placenta pericyte were mixed and co-cultured. RESULTS: Unlike the three-layered vascular plexus found in retinal angiogenesis of a normal mouse, angiogenesis in the OIR model is identified by the neovascular tuft extending into the vitreous. Neovascular tufts and the three-layered vascular plexus were both covered with pericytes in the OIR model. In this pathologic vascularization, N-cadherin, known to be crucial intercellular adhesion molecule, was also present. Further evaluation using the microfluidic in vitro model, successfully developed a microvascular network of endothelial cells covered with pericytes, mimicking normal retinal angiogenesis within 6 days. CONCLUSIONS: Pericytes covering endothelial cells were observed not only in vasculature of normal retina but also pathologic neovascularization of OIR mouse at P17. Factors involved in the endothelial cell-pericyte interaction can be evaluated as an attractive novel treatment target. These future studies can be performed using microfluidic systems, which can shorten the study time and provide three-dimensional structural evaluation.

Short-Term Clinical Results of Hyperopic LASEK in Korean Patients

PURPOSE: To evaluate short-term clinical outcomes following hyperopic laser-assisted subepithelial keratomileusis (LASEK) in Korean patients. METHODS: This retrospective study included 18 eyes of 10 patients who underwent hyperopic LASEK between May 2005 and March 2013 in Seoul National University Hospital. Visual acuity and spherical equivalent were evaluated preoperatively and at 1 and 3 months postoperatively. High order aberrations and contrast sensitivity were measured before and 3 months after the operation. Alternative prism cover test (APCT) was performed both preoperatively with correction and postoperatively without correction. RESULTS: The mean age of patients was 32 +/- 11 years and the mean spherical equivalent refractive error was -2.95 +/- 1.24 diopters (D). Uncorrected visual acuities were log MAR +0.17 +/- 0.15 and log MAR +0.14 +/- 0.15 at postoperative 1 month and 3 months, respectively and showed no significant difference in best corrected visual acuity (+0.25 +/- 0.30). Spherical equivalent was -0.22 +/- 1.22 D at 1 month and 0.38 +/- 0.91 D at 3 months postoperatively. In 6 patients who had esotropia before the operation, APCT was 7.83 +/- 3.60 prism diopters (PD) esotropia at distance with correction preoperatively and 4.67 +/- 5.65 PD at distance without correction postoperatively. Three patients (16.7%) showed delayed wound healing with 1 (5.56 %) having persistent corneal opacity without significant visual loss. CONCLUSIONS: The effect of LASEK may be comparable for correcting hyperopia and esotropia when compared with the effect of LASIK in previous reports; however, delayed wound healing may be a concern.

Orbital Dirofilariasis

No abstract available.

The Effectiveness of a Low-dose Oral Diazepam Treatment to Prevent Recurrence of Febrile Seizures / 대한소아신경학회지

PURPOSE: This study was aimed to investigate the optimum dose of diazepam to reduce the recurrence of febrile seizures and side effects in children with febrile seizures. METHODS: The subjects of this study included 528 children with febrile seizures (3 months-5 years of age) who were admitted to Eulji University Hospital (Daejeon, Korea) from January 2008 to December 2011. The children divided into four groups according to the dose of diazepam; Group I, 121 patients, received no diazepam therapy, group II, 129 patients, received oral diazepam in a single dose of 0.1 mg/kg after the febrile seizures, group III, 127 patients, 0.2 mg/kg, and group IV, 151 patients, 0.3 mg/kg, respectively. RESULTS: Seizures recurred in 6 of 129 children (4.7%) in group II, 1of 127 children (0.8%) in group III, and none of 151 children in group IV recurred. For the 121 untreated patients, febrile seizures recurred in 20 (16.5%) children. This study revealed a significant difference in the rate of recurrence of febrile seizures between children treated with diazepam and those who were not. And the recurrence rate was decreased by the increment of the dosage of diazepam, but there was no significant difference between groups. The side effects were observed in 19.9% of children treated with diazepam, 3.9% in group II, 12.6% in group III, and 39.7% in group IV, The rate of side effect was also increased with the increment of the dosage. CONCLUSION: An oral diazepam therapy will reduce the incidence of recurrent febrile seizures during the same febrile illnesses. We think the optimum dose of diazepam is 0.1 mg/kg or 0.2 mg/kg rather than 0.3 mg/kg. However, the use of oral diazepam after a febrile seizure should be carefully considered with weighing the benefits and potential adverse effects.

A case of Kawasaki disease with coexistence of a parapharyngeal abscess requiring incision and drainage / 소아과

Kawasaki disease (KD) causes multisystemic vasculitis but infrequently manifests with deep neck infections, such as a peritonsillar abscess, peritonsillar or deep neck cellulitis, suppurative parapharyngeal infection, or retropharyngeal abscess. As its etiology is still unknown, the diagnosis is usually made based on typical symptoms. The differential diagnosis between KD and deep neck infections is important, considering the variable head and neck manifestations of KD. There are several reports on KD patients who were initially diagnosed with retropharyngeal abscess on on computed tomography scans (CT). However, the previously reported cases did not have abscess or fluid collection on retropharyngeal aspiration. Therefore, false-positive neck CT scans have been obtained, until recently. In this case, suspected neck abscess in patients with KD unresponsive to intravenous immunoglobulin could signal the possible coexistence of suppurative cervical lymphadenitis.