The Effect of Obstructive Sleep Apnea on DNA Damage and Oxidative Stress

ObjectivesObstructive sleep apnea syndrome (OSAS) is associated with repeated hypoxia and re-oxygenation. This characteristic of OSAS may cause oxidative stress and DNA damage. However, the link of OSAS with oxidative stress and DNA damage is still controversial. In the current study, we investigated whether OSAS causes DNA damage using alkaline single-cell gel electrophoresis (comet assay) and measuring oxidative stress by monitoring serum malondialdehyde (MDA) levels.MethodsFrom March 2009 to August 2010, 51 patients who underwent polysomnography (PSG) during the night were enrolled in this study. We obtained serum from the patients at 6 AM. DNA damage and oxidative stress were evaluated using a comet assay and measuring serum MDA, respectively. We divided the patients into two groups according to the existence of comets appearing in the comet assay. Group 1 included 44 patients with negative assay results and group 2 consisted of seven patients with positive comet assay findings. We compared the age, gender proportion, PSG data (respiratory disturbance index [RDI], lowest O2 saturation level, and arousal index [AI]), time of disease onset, smoking habits, and serum MDA levels between the two groups.ResultsThe average age and gender proportion of the two groups were not statistically different (P>0.05). The average of RDI for group 1 was 30.4±18.4 and 8.0±7.7 (P0.05). No relationship between positive comet assay results and OSAS severity was identified.ConclusionResults of the current study showed that OSAS was not associated with DNA damage as measured by comet assays or oxidative stress according to serum MDA levels

Comparison of Component-Resolved Diagnosis by Using Allergen Microarray With the Conventional Tests in Allergic Rhinitis Patients: The First Using in Korea

ObjectivesThe aim of this study was to evaluate the component-resolved diagnosis using a microarray allergen chip (Immuno Solid-phase Allergen Chip, ImmunoCAP ISAC) and to compare this new diagnostic tool with the established ImmunoCAP methods for allergen-specific IgE detection in allergic rhinitis patients.MethodsOne hundred sixty-eight allergic rhinitis patients were included in this study. All the patients were diagnosed with allergic rhinitis according to their clinical symptoms, physical examination and a positive skin prick test. We analyzed their specific IgEs for house dust mites (Dermatophagoides farine [DF] and Dermatophagoides pteronyssinus [DP]), Alternaria alternata, birch, and mugwort using ImmunoCAP and ImmunoCAP ISAC in the same patient sample. We compared the sensitivity and correlation between the two tests.ResultsIn cases of allergies to DP and DF, the sensitivity of the specific IgE was 80% and that of the allergen microarray was 78.9%. The correlation between the two tests was significant for both DP and DF (P<0.001). For the A. alternata, birch and mugwort allergens, the sensitivity of ImmunoCAP ISAC was slightly lower than that of ImmunoCAP.ConclusionThese results suggest that the allergen microarray chip method is a reliable new method to diagnose the components of an allergen in patients with allergic rhinitis sensitive to house dust mites. Further study about the utility of the allergen microarray is needed

Spectroscopic ellipsometric study of ZnO and Zn1-xMgxO thin films grown on (0001) sapphire substrate

We grew ZnO and Zn1-xMgxO thin films on (0001) sapphire substrates by using metal-organic vapor phase epitaxy and measured the pseudo-dielectric functions using variable-angle spectroscopic ellipsometry. We analyzed the pseudo-dielectric functions by using the multi-layer model. The dielectric functions were fitted by using a Holden model dielectric function. We used anisotropic layer modeling for the ZnO thin film, whereas we adopted the approximation of isotropic layer modeling for the Zn1-xMgxO alloys. We also discuss the Mg composition dependence of the bandgap and the binding energy in Zn1-xMgxO alloys, and consider the valence-band ordering in ZnO thin films.The work of H. Lee was supported in part by the Special Equipment Program of the Korean Basic Science Institute through the Korean Science and Engineering Foundation (KOSEF, R23-2002-000-00006-0). The work of G.-C. Yi was supported by the Advanced Environmental Biotechnology Research Center (No. R11-2003-006)

Delayed Treatment of Zygomatic Tetrapod Fracture

Since maxillofacial injury is frequently accompanied by other diseases, its evaluation and treatment are open delayed. When the evaluation is delayed, the surgical treatment can be difficult or impossible. A 21-yr-old man presented with right facial swelling and deformity after injury. We planned immediate surgical repair for his right tetrapod fracture, but the operation was delayed for two months due to severe hyperthyroidism. During the operation, we reducted and fixed the deviated bone after refracture of the zygomatic arch with an osteotome to achieve mobility. The facial deformity and difficulty in mouth opening were improved after the operation. Even in the presence of accompanying fractures, early evaluation and proper management can prevent complications and achieve acceptable cosmetic outcomes in maxillofacial trauma patients. In patients with malunion of fracture sites, fixation after refracture using an osteotome can be a good treatment option for obtaining good mobility

Heteroepitaxal fabrication and structural characterization of ultrafine GaN/ZnO coaxial nanorod heterostructures

We report on heteroepitaxial fabrication and structural characterizations of ultrafine GaN/ZnO coaxial nanorod heterostructures. The coaxial nanorod heterostructures were fabricated by epitaxial growth of a GaN layer on ultrafine ZnO nanorods. Epitaxial growth and precise control of GaN overlayer thickness were obtained by low pressure metalorganic vapor-phase epitaxy. ZnO nanorods grown on Si and sapphire substrates using catalyst-free metalorganic chemical vapor deposition exhibited diameters as small as 7 nm. Furthermore, structural properties of the coaxial nanorod heterostructures were investigated using both synchrotron-radiation x-ray diffraction and high resolution transmission electron microscopy. (C) 2004 American Institute of Physics

Pig-to-Nonhuman Primate (NHP) Naked Islet Xenotransplantation

Islet transplantation is an established therapy for selected type 1 diabetes (T1D) patients with severe hypoglycemic unawareness and glycemic liability despite of insulin treatment. However, the donor organ is limited. Porcine islets are the best alternative source to overcome this limitation, and pig-to-nonhuman primate (NHP) naked islet xenotransplantation studies are being performed worldwide. Several studies including our own have presented successful proof-of-concept results based on immunosuppression regimen including the anti-CD154 monoclonal antibody. Particularly, long-term control of diabetes by adult porcine islet transplantation has been demonstrated in five consecutive monkeys, and the longest survival was ~1000 days after transplantation. Currently, pig-to-NHP islet xenotransplantation based on clinically applicable immunosuppression regimen is being pursued. In this chapter, we will describe all the procedures of pig-to-NHP naked islet xenotransplantation: (1) the porcine islet isolation from designated pathogen-free (DPF) miniature pigs, (2) diabetes induction in monkeys, (3) transplantation procedure via the portal vein, (4) immune monitoring comprising humoral and cellular immunity after porcine islet transplantation, and finally (5) liver biopsy and subsequent immunohistochemical procedure in detail

Low Concentration PM Had No Effect on Nasal Symptoms and Flow in Allergic Rhinitis Patients

Objectives Since Korea is geographically close to China (the origin site for Asian sand dust [ASD]) the health influence of ASD event will be still greater in Korea. We aimed to evaluate the effect of PM10 (particulate matter with aerodynamic diameter 100 μg/m3) Results There was no significant difference between group A and B in nasal symptoms and PNIF during the 120-day period. Changes in nasal symptoms and PNIF were not statistically significant before or after a PM10 concentration rise above 100 μg/m3. Conclusion Low concentration PM10 does not have significant effect on nasal symptoms and PNIF in AR patients