Joo-Hyung Lee

A gold nanorod-based optical DNA biosensor for the diagnosis of pathogens

A novel optical biosensor for detecting target DNA, utilizing gold nanorods (GNRs) as molecular probes is demonstrated. This sensor is based on simultaneous biorecognition-mediated hybridization of target DNA in a sandwich type manner with two different capture probe DNA sequences modified separately with identical sets of GNRs, which leads to aggregation of GNRs. The hybridization induced aggregation as revealed by TEM analysis, promotes the modulation of surface plasmon resonance of GNRs, which forms the basis of complementary target DNA detection from the Chlamydia trachomatis pathogen. Thermally induced reversible dissociation of hybridized DNA is demonstrated by melting analysis. The present sensing strategy is successfully demonstrated by detecting PCR amplified C. trachomatis pathogen gene isolated from human urine sample in a concentration range of 0.25-20 nM. Furthermore, this sensor displays excellent specificity by discriminating the target DNA versus other non-specific pathogenic genes.

Rhinocerebral Mucormycosis: consideration of prognostic factors and treatment modality.

OBJECTIVES Rhinocerebral mucormycosis is rare, rapidly progressive, potentially life-threatening disease, and it usually occurs in immunocompromised patients. We present our clinical experience with 12 cases and we attempt to identify the prognostic features and proper treatment protocols. PATIENTS AND METHODS All the cases of mucormycosis were proven by histology or culture. The prognosis was analyzed according to the predisposing factors, including underlying disease, extent of disease and surgical intervention. RESULT The overall mortality rate in our series was 33.3%. 7 of the 10 operated patients recovered, while 1 of the 2 non-operated patients expired. The associated conditions included diabetes mellitus (n=9) and hematological disease (n=3). A poor prognosis was primarily related with uncontrolled underlying disease. Other associated prognostic factors were the extent of disease including orbital or intracranial extension. Surgical debridement is essential for a good prognosis, but timely intervention and complete aggressive debridement are not always needed in all patients. The patient who had slowly progressive disease also survived after conventional medical management and limited surgical debridement, including orbital preservation. CONCLUSION Control of the underlying predisposing illness along with prompt parenteral administration of amphotericin B and aggressive surgical debridement remain the essential treatments even today. Contrary to this, as described in this study, for the patients with slowly progressive disease, the aggressive surgical debridement is spared, and a successful result may be obtained with the conventional management, including medical treatment and timely limited surgical intervention.

The role of temporalis fascia for free mucosal graft survival in small nasal septal perforation repair.

AbstractTemporalis fascia has been used widely as a interposition graft for mucosal rotation flap in nasal septal perforation repair. However, the exact role of temporalis fascia in healing process has not yet been clarified. For the pedicle of rotation flap has been considered as a major vehicle for nutrition distribution, the role of temporalis fascia has been devaluated. In this study, we experienced small nasal septal perforation repairs using free mucosal graft not having pedicles but covered by temporalis fascia. Three patients with small nasal septal perforations not larger than 1 × 1 cm2 were included. In 2 patients, the perforations were repaired using free composite grafts from the inferior turbinate mucosa covered by continuous temporalis fascia not divided, and the surgical results were successful with complete healings. In 1 patient, however, the temporalis fascia was divided into 2 parts to better fit the shape of the perforation, and the graft failed to survive. These surgical results suggest that the temporalis fascia might have an important role in healing process of nasal septal defect and could be used as a beneficial options for small mucosal defect repair surgeries using free mucosal grafts.

The effect of urban particulate matter on cultured human nasal fibroblasts: Effect of UPM on fibroblasts

Exposure to urban particulate matter (UPM) has been linked to aggravation of various health problems. Although the effects of UPM on the lower respiratory tract have been extensively studied, more research is required on the impact of UPM on the upper respiratory tract and the underlying mechanisms. Thus, we investigated the cytotoxic effects of UPM on cultured human nasal fibroblasts, the underlying signaling pathways involved, and changes in cytokine levels.

Anti-Interleukin-9 Antibody Increases the Effect of Allergen-Specific Immunotherapy in Murine Allergic Rhinitis

Purpose Interleukin (IL)-9 induces allergic responses; however, the roles of anti-IL-9 antibody in the induction of tolerance remain unclear. This study investigated the effects of anti-IL-9 antibody on oral tolerance (OT) in a mouse model of allergic rhinitis (AR). Methods BALB/c mice were divided into 4 groups: the control, AR, OT, and OT with anti-IL-9 antibody (OT+IL9AB) groups. Ovalbumin (OVA) was used for sensitization and challenge. Mice in the OT and OT+IL9AB groups were fed OVA for immunotherapy. During immunotherapy, OT+IL9AB mice were injected with anti-IL-9 antibody. Allergic symptoms, tissue eosinophil counts, and serum OVA-specific immunoglobulin E (IgE) were measured. The mRNA expressions of cytokines and transcription factors of T cells of nasal mucosa were determined by real-time polymerase chain reaction (PCR). The protein levels of GATA3, ROR-γt, and Foxp3 in nasal mucosa were determined by Western blot. CD4+CD25+Foxp3+ T cells in the spleen were analyzed by flow cytometry. Results Administration of anti-IL-9 antibody decreased allergic symptoms, OVA-specific IgE levels, and eosinophil counts. In addition, it inhibited T-helper (Th) 2 responses, but had no effect on Th1 responses. Protein levels of ROR-γt and mRNA levels of PU.1 and ROR-γt were reduced by anti-IL-9 antibody. Anti-IL-9 antibody increased Foxp3 and IL-10 mRNA expression, Foxp3 protein, and induction of CD4+CD25+Foxp3+ T cells. Conclusions Anti-IL-9 antibody decreased allergic inflammation through suppression of Th2 and Th17 cells. Anti-IL-9 antibody enhanced the tolerogenic effects of regulatory T cells. These results suggest that anti-IL-9 antibody might represent a potential therapeutic agent for allergen immunotherapy in patients with uncontrolled allergic airway disease.