A new HLA-B*15 allele, HLA-B*9587, identified by sequence-based typing in a Korean individual.

A new HLA-B*9587 showed one nucleotide difference from B*15010101 at nucleotide 127 with substitution G-->C (codon 19 GAG-->CAG) resulting in a coding change from Glu to Gln (E19Q).

Epidemiology of group B streptococcus in Korean pregnant women.

Between January 2006 and May 2008, 2624 pregnant S. Korean women between 35-37 weeks gestation were screened for group B streptococcus (GBS). Resistance to antimicrobials was tested by disk diffusion and serotype determined using co-agglutination assays and microarray methods. Overall, 8% of pregnant women were colonized. Serotype III was the predominant serotype (43.8%), followed by serotypes V (20.3%), Ia (12.1%), and Ib (9.5%). GBS was frequently resistant to clindamycin (54.0%) and erythromycin (25.6%); 3.7% were resistant to cefazolin. More than three-quarters of serotype V were resistant to clindamycin or erythromycin or both, and 71% of serotype III were resistant to clindamycin but only 12% were resistant to erythromycin. GBS prevalence exceeded earlier reports by one-third. This is the first report of cefazolin resistance in Korea. These results underscore the need to establish screening measures and chemoprophylaxis guidelines regarding GBS infections in Korea.

Identification of a novel HLA-Cw*04 allele, HLA-Cw*040106, by sequence-based typing in the Korean population.

A new human leukocyte antigen-Cw*0401 allele showed one nucleotide difference from Cw*04010101 in exon 3 at nucleotide position 561 (codon 163 ACG-->ACT) without a coding change.

Microstructural properties of phase-change Ge2Sb2Te5 nanoparticles grown by pulsed-laser ablation.

We have introduced in-situ growth of Ge2Sb2Te5 (GST) nanoparticles with 10 nm of average diameter by pulsed laser ablation directly on Pt/Ir-coated AFM tips and investigated their microstructure and phase formation using scanning and transmission electron microscopy. In addition, Fourier transform analysis of electron micrographs discloses the crystal structure of the Ge2Sb2Te5 phase which has a lattice constant with approximately 6 A like bulk value of face-centered cubic and hexagonal structure.

Topographic anatomy of the inferior wall of the maxillary sinus in Koreans.

Knowledge of the relationship between the root apex and the inferior wall of the maxillary sinus are crucial for diagnosing and treating a sinus pathosis as well as in assisting in dental implantation. Therefore, identifying the proximity between the root apex and the inferior wall of the sinus and clarifying the cortical thickness of the inferior wall of the sinus is essential for determining the topography of a spreading dental infection into the maxillary sinus. Accordingly, knowledge of the topography between the root apex and the inferior wall of maxillary sinus is important for diagnosing and planning dental implantation, endodontic procedures, and orthodontic treatment. This study was undertaken to clarify the morphological and clinical characteristics of the maxillary sinus, particularly the inferior wall of the sinus in Koreans, and to identify the relationship between the inferior wall of the maxillary sinus and the roots of the maxillary teeth. Twenty-four sides of the maxillae of hemi-sectioned Korean heads were used in this study. All specimens were decalcificated and sectioned coronally. On the sectioned specimens, 21 items were measured using an image analyzing system. The distances between the each root apex and the inferior wall of the maxillary sinus were measured. The distance from the root apex to the inferior wall of the sinus was the shortest in the second molar area and the longest in the first premolar area. The thickness of the cortical plate of the inferior wall of the maxillary sinus was thinnest in the first premolar area but it was thickest in the second premolar area. The vertical relationship between the inferior wall and the roots of the maxillary molars was classified into five types. Type I (the inferior wall of the sinus located above the level connecting the buccal and lingual root apices) dominated (54.5% in the first molar area, 52.4% in the second molar area). The horizontal relationship between the inferior wall of the sinus and the root apex was classified into three types. Type 2 (the alveolar recess of the inferior wall of the sinus was located between the buccal and lingual roots) was most common (80% in the first and second molar area). Overall, this study demonstrated the many anatomical characteristics and determined the relationships between the maxillary sinus and their surrounding structures. These findings may have an impact on the clinical management of patients.

An adaptive M-wave canceler for the EMG controlled functional electrical stimulator and its FPGA implementation.

Biopotential signals have been used as command and feedback signals in systems using electrical stimulation of motor nerves to restore the lost function. In order to use the voluntary electromyography (EMG) as a control signal for the functional electrical stimulation of the same muscle, it is necessary to suppress the M-wave evoked by the electrical stimulation. We present a Gram-Schmidt (GS) prediction error filter which effectively eliminates the M-wave from voluntary EMG. The GS filter has systolic array structure, so it offers advantages for the real-time processing on the field programmable gate array (FPGA). On basis of the data obtained from model for M-wave and voluntary EMG and from CNS injury patient, the proposed GS filter showed a very promising performance.

A case of mitochondrial trifunctional protein deficiency diagnosed by acylcarnitine profile and DNA analysis in a dried blood spot of a 4-day-old boy.

We report a Korean case, consistent with a biochemical diagnosis of trifunctional protein (TFP) deficiency, in which molecular diagnosis revealed a novel mutation in the alpha-subunit of TFP and the rare combination of two intergenic region (C/C and G/G) polymorphisms.

Personal-computer-based three-dimensional reconstruction and simulation of maxillary sinus.

Anatomical descriptions of the maxillary sinus are critical in pathological diagnosis and the treatment planning of surgical procedures. This study was undertaken to develop a new technique for simulating anatomical structures and to clarify the morphological and clinical characteristics of the maxillary sinus. Thirty-three hemi-sectioned Korean heads were used in this study. CT scans and DentaScan reformatted cross-sectional images were taken on all specimens. From the CT images, three-dimensional reconstructed images were made using the V-works program. From the three-dimensional reconstructed images of the maxillary sinus, six categories of maxillary sinus were created, categorized according to their lateral aspects and shapes of the inferior walls. In 55%, a flat inferior wall of the maxillary sinus was observed. All measurements (anterior-posterior length, height, width and volume) of the sinus were larger in males than in females. From the DentaScan reformatted panoramic images, the anterior limit of the maxillary sinus was located in the first premolar area (58%), and the posterior limit was in the third molar and maxillary tuberosity area (94%). We therefore offer a new virtual technique for manipulating three-dimensional reconstructed images easily on a personal computer. On the reconstructed images the three-dimensional morphology could be observed and the anatomical characteristics of the maxillary sinus and surrounding structures could be determined.

Diagnostic patterns of very-long-chain fatty acids in plasma of patients with X-linked adrenoleukodystrophy.

Pattern recognition analysis on the levels of the very-long-chain fatty acids (VLCFAs) in plasma is described for the visual discrimination of X-linked adrenoleukodystrophy (X-ALD) patients from normal healthy group. Plasma VLCFA compositions of 58 normal subjects and 16 X-ALD patients were examined by gas chromatography as their methyl esters to determine the area percentages of behenic acid (C22:0), lignoceric acid (C24:0) and hexacosanoic acid (C26:0) in the total fatty acids, and the concentration (microg/ml) of C26:0. When star symbol plotting was applied to the VLCFA values of C22:0 (%), C24:0 (%), C26:0 (%), C24:0/C22:0, C26:0/C22:0 and C26:0 (microg/ml) after normalization to the corresponding median values in normal group, the resulting deformed hexagonal star pattern was characteristic of each patient. Therefore, simple visual comparison with the equilateral hexagon of normal group average as the control pattern enabled one readily to discriminate X-ALD patients from the normal group. Additionally, canonical discriminant analysis performed on the six unnormalized VLCFA values correctly classified 74 plasma specimens into two separate clusters according to normal subject or X-ALD patient in the canonical plot.

Design of a wavelet interpolation filter for enhancement of the ST-segment.

A wavelet interpolation filter (WIF) is designed for the removal of motion artifacts in the ST-segment of stress ECGs. The WIF consists of two parts. One part is a wavelet transform that decomposes the stress ECG signal into several frequency bands using a Haar wavelet. The other part is an interpolation method, such as the spline technique, that is used to enhance the reconstruction performance of the signal decomposed by the wavelet transform. To evaluate the performance of the WIF, three indices are used: signal-to-noise ratio (SNR), reconstruction square error (RSE) and standard deviation (SD). The MIT/BIH arrhythmia database, the European ST-T database and the triangular wave are used for evaluation. A noisy ECG signal, corrupted by motion artifacts, is simulated by the addition of two types of random noise to the original ECG signal. For comparison, three indices for the other methods are also computed: mean, median and hard thresholding. The performance of the WIF shows that RSE, SNR and SD are 392.7, 18.3dB and 2.6, respectively, in the case of a noisy signal with an SNR of 7.1 dB. This result is much better than those for the other methods.

Therapeutic trial in the first three Asian cases of ethylmalonic encephalopathy: response to riboflavin.

Three Korean girls with ethylmalonic encephalopathy, the first Asian cases, were identified. In all three cases, we observed slight improvement in motor functions, cognitive behaviours and chronic mucoid diarrhoea after treatment with riboflavin and/or coenzyme Q10 treatment. The precise pathogenesis of ethylmalonic encephalopathy has not been fully elucidated, but riboflavin treatment may be helpful.

Gas chromatographic-mass spectrometric determination of plasma saturated fatty acids using pentafluorophenyldimethylsilyl derivatization.

An improved method for the detection of 11 saturated fatty acids (SFAs) including C12:0-C26:0 (even numbers only), C17:0, C19:0 and C23:0 in human plasma by gas chromatography-mass spectrometry (GC-MS) with a stable isotope internal standard as d3-stearic acid is described. This procedure was based on acidic treatment, liquid-liquid extraction, and chemical derivatization prior to instrumental analysis. Eleven pentafluorophenyldimethylsilyl-SFA derivatives were well separated without any interfering peaks in plasma samples. The characteristic ions at M-15, constituting the base peaks in the electron impact mass spectra for 11 SFAs, permitted their sensitive detection by GC-MS in the selected ion monitoring (SIM) mode. The SIM responses were linear with correlation coefficients varying from 0.993 to 0.999 in the concentration range of 0.05 to approximately 50 microg/ml for the 11 SFAs. The detection limits for SIM of the SFAs varied in the range of 0.05 to approximately 10.0 pg. When applied to the plasma samples of normal subjects and patients with X-linked adenoleukodystrophy, which is one of the hereditary peroxisomal disorders, the present method enabled us to determine the SFAs with good sensitivity and good overall precision and accuracy within the concentration ranges of 0.14 to approximately 82.35 micromol/l.

Long-term use of preservatives on rat nasal respiratory mucosa: effects of benzalkonium chloride and potassium sorbate.

OBJECTIVES: The preservatives benzalkonium chloride (BZC) and potassium sorbate (PS) are widely used, not only for nasal drops, but also for eyedrops and cosmetics. However, there have been many case reports that consider lesions such as dermatitis or conjunctivitis to be the results of irritation induced by BZC or PS. METHODS: We evaluated the histological changes after the long-term administration of BZC or PS on rat nasal respiratory mucosa. Forty rats were used for the BZC group and 40 rats for PS group. Animals in each group were divided into four subgroups The first subgroup received a low-concentration preservative solution that was commonly used for nasal sprays. The second subgroup received a high-concentration preservative solution that was reported to induce dermatitis in humans. The third and fourth subgroups received a steroid mixed preservative solution of low and high concentrations, respectively. The control group was administrated normal saline. After each group received 1, 2, and 4 weeks of topical administration, the symptomatic and histological changes on H&E stain were observed. RESULTS: Sneezing and nasal rubbing with forelegs were observed in almost all subgroups by the seventh day of treatment. The preservatives induced nasal lesions, including intraepithelial glandular formation, inflammatory cell infiltration, vascular hyperplasia, and edematous change. The symptomatic and histological changes were pronounced with the prolonged duration of administration. Similar results were observed in the steroid mixed-solution groups. In the PS steroid mixed-solution group, however, symptoms and nasal lesions were reduced with the prolonged duration of administration. CONCLUSION: It is our finding that even a low-concentration solution of preservative can lead to nasal lesion. Hence there is a strong need to develop both a preservative that can be safely and widely used and a nasal spray without preservatives.

Very long chain acyl coenzyme A dehydrogenase deficiency in a 5-month-old Korean boy: identification of a novel mutation.

A 5-month-old Korean boy who presented with lethargy and cardiomyopathy was diagnosed with very long chain acyl coenzyme A dehydrogenase (VLCAD) deficiency by organic acid, fatty acid, acylcarnitine, and molecular genetic analysis. The patient was a compound heterozygote for mutations in the VLCAD gene. One allele contains a 3-bp deletion in exon 6, deleting glutamic acid in codon 130 (E130del ); this allele is of paternal origin. The patient's maternally derived allele is a novel mutation, C1843T in exon 20, which creates a premature termination codon (R615stop ). Although molecular genetic characterization of VLCAD deficiency is limited to a few patients, heterogeneity of mutations is already apparent. However, the E130del is a relatively frequent mutant allele, which has been noted in 2 previously identified patients. The 2 mutant alleles in our patient appear to be responsible for his severe and fatal clinical manifestations.

Sudden and unexpected neonatal death: a protocol for the postmortem diagnosis of fatty acid oxidation disorders.

Fatty acid oxidation (FAO) disorders are frequently reported as the cause of sudden and unexpected death, but their postmortem identification remains difficult. Over a period of 5 years, the authors have identified 44 cases representing five FAO disorders and 19 additional cases without a diagnosis of a specific defect. Among the two groups, 13 patients died in the neonatal period, 10 in the FAO group, and three from the undetermined defect group. This outcome was consistently associated with exclusive breast feeding and presumably poor caloric intake. The diagnosis of FAO disorder in these cases was based on the analysis of postmortem liver and bile. In postmortem liver, informative findings are microvesicular steatosis, elevated fatty acid concentrations, glucose depletion, and low carnitine concentration. Bile carnitine analysis and acylcarnitine profiling have expanded significantly the effectiveness of the initial protocol and could lead, based on preliminary observations, to better identification of patients who may have been missed or left undetermined by the analysis of liver only. If an autopsy is not performed, informative findings can still be obtained by analysis of blood spots collected for newborn screenings and by biochemical testing of parents and asymptomatic siblings.

Size assessment of adenoid and nasopharyngeal airway by acoustic rhinometry in children.

Adenoid hypertrophy is known as the most common cause of nasal obstruction in children; thus, adenoidectomy with, or without, tonsillectomy is one of the most commonly performed surgical procedures in the paediatric population. Although many methods have been suggested, few studies have reported on how to assess adenoid size, pre-operatively. Acoustic rhinometry is an objective technique as well as a non-invasive method, which can be easily used in young children. This study confirmed that acoustic rhinometry is a non-invasive and objective technique for assessing the geometry of the nasal cavity and nasopharynx. Forty children were evaluated using symptomology, two different radiological measurements and acoustic rhinometry; the results were compared with endoscopic findings. Clinical symptoms and A/N ratio measured with Fujioka's method significantly correlated with the endoscopic assessment findings (r = 0.769 and 0.604 respectively). Significant increases in the cross-sectional area and volume of the nasopharynx were observed at the adenoid notch after adenoidectomy (p < 0.005 and p < 0.005, respectively). Acoustic rhinometry showed a high degree of correlation of which adenoid occupied the nasopharyngeal airway under endoscopic examination (r = 0.771). Thus, the study concluded that acoustic rhinometry can be as good an objective method for measuring adenoid sizes as endoscopy and can be used as one of the pre-operative examination tools for adenoidectomy.

Epoxyalkanoyls as novel ACE inhibitors.

The epoxyalkanoyl derivatives were designed and synthesized as ACE inhibitors. Coupling of unsaturated carboxylic acids with amino acids and following epoxidation with dimethyldioxirane gave the epoxyalkanoyls with high yield. The inhibitory activity of synthesized compounds on angiotensin converting enzyme was IC50 values of 0.06-5.5 microM.

Application of a wavelet adaptive filter to minimise distortion of the ST-segment.

A wavelet adaptive filter (WAF) for the removal of baseline wandering in ECG signals is described. The WAF consists of two parts. The first part is a wavelet transform that decomposes the ECG signal into seven frequency bands using Vaidyanathan-Hoang wavelets. The second part is an adaptive filter that uses the signal of the seventh lowest-frequency band among the wavelet transformed signals as primary input and a constant as reference input. To evaluate the performance of the WAF, two baseline wandering elimination filters are used, a commercial standard filter with a cutoff frequency of 0.5 Hz and a general adaptive filter. The MIT/BIH database and the European ST-T database are used for the evaluation. The WAF performs better in the average power of eliminated noise than the standard filter and adaptive filter. Furthermore, it shows a lower ST-segment distortion than the standard filter and the adaptive filter.