Normal Korean Research Articles

Morphometric Evaluation of the Thoracic and Lumbar Vertebral Canal and Spinal Cord Using Computed Tomography in Healthy Korean Shorthair Cats.

This study aimed to evaluate the spinal morphometry of the thoracic and lumbar regions in normal Korean Shorthair cats using computed tomography (CT) and to investigate the relationship with variables such as sex, age and body weight. Fifteen clinically healthy Korean Shorthair cats (eight males, seven females) from Seoul National University Veterinary Medical Teaching Hospital were included in this retrospective study. Measurements of the height, width and area of the vertebral canal and spinal cord on CT images were taken at the cranial, middle and caudal points of the thoracic and lumbar vertebrae by three observers, and the ratios of the spinal cord area to the vertebral canal area were calculated. The significance of the differences in measurements between sexes and correlations with age and body weight were analysed. The mean age of the cats was 7 years (range: 2-12 years), with a mean weight of 5.27 kg (range: 2.6-8.3 kg). The height, width and area of the vertebral canal and spinal cord were significantly greater in males than in females (p < 0.05). The ratios of the spinal cord area to the vertebral canal area showed no significant difference between sexes (p > 0.05), and no significant correlations were found between the ratios of the spinal cord area to the vertebral canal area and age or body weight. This study provides useful reference intervals for spinal morphometry in the thoracic and lumbar regions of healthy Korean Shorthair cats and investigate the relationship with variables such as sex, age and body weight. This anatomical information may assist in the diagnosis and prognosis of thoracic, lumbar vertebral and spinal cord diseases using CT.

Construction and validation of a brain magnetic resonance imaging template for normal older Koreans

BackgroundSpatial normalization to a standardized brain template is a crucial step in magnetic resonance imaging (MRI) studies. Brain templates made from sufficient sample size have low brain variability, improving the accuracy of spatial normalization. Using population-specific template improves accuracy of spatial normalization because brain morphology varies according to ethnicity and age.MethodsWe constructed a brain template of normal Korean elderly (KNE200) using MRI scans 100 male and 100 female aged over 60 years old with normal cognition. We compared the deformation after spatial normalization of the KNE200 template to that of the KNE96, constructed from 96 cognitively normal elderly Koreans and to that of the brain template (OCF), constructed from 434 non-demented older Caucasians to examine the effect of sample size and ethnicity on the accuracy of brain template, respectively. We spatially normalized the MRI scans of elderly Koreans and quantified the amount of deformations associated with spatial normalization using the magnitude of displacement and volumetric changes of voxels.ResultsThe KNE200 yielded significantly less displacement and volumetric change in the parahippocampal gyrus, medial and posterior orbital gyrus, fusiform gyrus, gyrus rectus, cerebellum and vermis than the KNE96. The KNE200 also yielded much less displacement in the cerebellum, vermis, hippocampus, parahippocampal gyrus and thalamus and much less volumetric change in the cerebellum, vermis, hippocampus and parahippocampal gyrus than the OCF.ConclusionKNE200 had the better accuracy than the KNE96 due to the larger sample size and was far accurate than the template constructed from elderly Caucasians in elderly Koreans.

Multi-Ethnic Norms for Volumes of Subcortical and Lobar Brain Structures Measured by Neuro I: Ethnicity May Improve the Diagnosis of Alzheimer's Disease1.

We previously demonstrated the validity of a regression model that included ethnicity as a novel predictor for predicting normative brain volumes in old age. The model was optimized using brain volumes measured with a standard tool FreeSurfer. Here we further verified the prediction model using newly estimated brain volumes from Neuro I, a quantitative brain analysis system developed for Korean populations. Lobar and subcortical volumes were estimated from MRI images of 1,629 normal Korean and 786 Caucasian subjects (age range 59-89) and were predicted in linear regression from ethnicity, age, sex, intracranial volume, magnetic field strength, and scanner manufacturers. In the regression model predicting the new volumes, ethnicity was again a substantial predictor in most regions. Additionally, the model-based z-scores of regions were calculated for 428 AD patients and the matched controls, and then employed for diagnostic classification. When the AD classifier adopted the z-scores adjusted for ethnicity, the diagnostic accuracy has noticeably improved (AUC = 0.85, ΔAUC = + 0.04, D = 4.10, p < 0.001). Our results suggest that the prediction model remains robust across different measurement tool, and ethnicity significantly contributes to the establishment of norms for brain volumes and the development of a diagnostic system for neurodegenerative diseases.

Radiographic and echocardiographic evaluation in rescued Korean raccoon dogs (Nyctereutes procyonoides koreensis).

Nyctereutes procyonoides koreensis (Korean raccoon dog), a member of the Canidae family, is anatomically similar to dogs. Previous studies have used vertebral heart scale measurements to measure the cardiac size of Korean raccoon dogs on thoracic radiographs; however, the use of additional cardiac size indices, such as vertebral left arial score, intercostal space, cardiothoracic ratio, and echocardiographic indices, has not been reported. Therefore, this study aimed to establish normal reference ranges for various thoracic radiographic and echocardiographic indices in normal Korean raccoon dogs. Twenty-six Korean raccoon dogs (11 males and 15 females) were included in this study. The thoracic radiographic indices, vertebral heart scale score, and vertebral left atrial score were measured in the right lateral view. The intercostal space and cardiothoracic ratio were measured in the ventrodorsal view. The echocardiograms were evaluated in the right parasternal long and short axis view and left parasternal apical view. The mean values for the thoracic radiographic and echocardiographic indices were as follows: vertebral heart scale, 9.12 ± 0.74; vertebral left atrial score, 1.5 ± 0.31; intercostal spaces, 3.17 ± 0.34; cardiothoracic ratio, 0.69 ± 0.07; left atrial to aortic root ratio, 1.22 ± 0.14; main pulmonary artery to aorta ratio, 1.22 ± 0.14; left ventricular end-diastolic internal diameter normalized for body weight, 1.36 ± 0.19; end-diastolic volume index, 51.07 ± 19.6; end-systolic volume index, 16.54 ± 7.45; the peak velocity of early diastolic transmitral flow, 73.13 ± 15.46 cm/s; and the ratio between the transmitral flow velocities and the peak early diastolic velocity, 1.77 ± 0.47. Only percent increase in the left ventricular end-systolic internal diameter was negatively correlated with body weight. The remaining indices showed no correlations with body weight. To the best of our knowledge, this is the first case report covering both thoracic radiographic and endocardiographic indices for Korean raccoon dogs. Thus, the thoracic radiographic and echocardiographic indices established in this study may be used to evaluate the cardiac condition of Korean raccoon dogs.

A streamlined pipeline based on HmmUFOtu for microbial community profiling using 16S rRNA amplicon sequencing.

Microbial community profiling using 16S rRNA amplicon sequencing allows for taxonomic characterization of diverse microorganisms. While amplicon sequence variant (ASV) methods are increasingly favored for their fine-grained resolution of sequence variants, they often discard substantial portions of sequencing reads during quality control, particularly in datasets with large number samples. We present a streamlined pipeline that integrates FastP for read trimming, HmmUFOtu for operational taxonomic units (OTU) clustering, Vsearch for chimera checking, and Kraken2 for taxonomic assignment. To assess the pipeline's performance, we reprocessed two published stool datasets of normal Korean populations: one with 890 and the other with 1,462 independent samples. In the first dataset, HmmUFOtu retained 93.2% of over 104 million read pairs after quality trimming, discarding chimeric or unclassifiable reads, while DADA2, a commonly used ASV method, retained only 44.6% of the reads. Nonetheless, both methods yielded qualitatively similar β-diversity plots. For the second dataset, HmmUFOtu retained 89.2% of read pairs, while DADA2 retained a mere 18.4% of the reads. HmmUFOtu, being a closed-reference clustering method, facilitates merging separately processed datasets, with shared OTUs between the two datasets exhibiting a correlation coefficient of 0.92 in total abundance (log scale). While the first two dimensions of the β-diversity plot exhibited a cohesive mixture of the two datasets, the third dimension revealed the presence of a batch effect. Our comparative evaluation of ASV and OTU methods within this streamlined pipeline provides valuable insights into their performance when processing large-scale microbial 16S rRNA amplicon sequencing data. The strengths of HmmUFOtu and its potential for dataset merging are highlighted.

Effects of Taekwondo Training on Growth Factors in Normal Korean Children and Adolescents: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

The growth of children and adolescents is both an important health indicator and a major public health issue. Many recent studies have investigated the effects of taekwondo on growth factors, but no consensus has yet been reached. This meta-analysis aimed to determine the effects of taekwondo on the growth factors in children and adolescents (aged 8 to 16 years). Randomized controlled trials from PubMed, Web of Science, Cochrane Library, the Research Information Sharing Service, the Korea Citation Index, and the Korean-studies Information Service System were analyzed. The effect sizes (standardized mean differences, SMD) were calculated, the risk of bias and publication bias were assessed, and the effect size and subgroup analyses were pooled. We found that the taekwondo group had significantly higher levels of growth hormones (SMD 1.78, 95% confidence interval [CI] 0.98-2.58, and p < 0.001) and insulin-like growth factors (SMD 1.76, 95% CI 0.60-2.92, and p < 0.001) than the control group. For height, a medium effect size was observed (SMD 0.62, 95% CI -0.56-1.80, and p = 0.300), but the between-group difference was not significant. Thus, taekwondo had significant positive effects on the secretion of growth hormones and insulin-like growth factors in Korean children and adolescents. A longitudinal follow-up is necessary to determine the effect on height. This suggests that taekwondo can be recommended as an appropriate physical exercise for maintaining normal growth in children and adolescents.

The UGT1A9*22 genotype identifies a high-risk group for irinotecan toxicity among gastric cancer patients.

Several studies have shown associations between irinotecan toxicity and UGT1A genetic variations in colorectal and lung cancer, but only limited data are available for gastric cancer patients. We evaluated the frequencies of UGT1A polymorphisms and their relationship with clinicopathologic parameters in 382 Korean gastric cancer patients. Polymorphisms of UGT1A1*6, UGT1A1*27, UGT1A1*28, UGT1A1*60, UGT1A7*2, UGT1A7*3, and UGT1A9*22 were genotyped by direct sequencing. In 98 patients treated with irinotecan-containing regimens, toxicity and response were compared according to the genotype. The UGT1A1*6 and UGT1A9*22 genotypes showed a higher prevalence in Korean gastric cancer patients, while the prevalence of the UG1A1*28 polymorphism was lower than in normal Koreans, as has been found in other studies of Asian populations. The incidence of severe diarrhea after irinotecan-containing treatment was more common in patients with the UGT1A1*6, UGT1A7*3 and UGT1A9*22 polymorphisms than in controls. The presence of the UGT1A1*6 allele also showed a significant association with grade III–IV neutropenia. Upon haplotype and diplotype analyses, almost every patient bearing the UGT1A1*6 or UGT1A7*3 variant also had the UGT1A9*22 polymorphism, and all severe manifestations of UGT1A polymorphism-associated toxicity were related to the UGT1A9*22 polymorphism. By genotyping UGT1A9*22 polymorphisms, we could identify high-risk gastric cancer patients receiving irinotecan-containing chemotherapy, who would experience severe toxicity. When treating high-risk patients with the UGT1A9*22 polymorphism, clinicians should closely monitor them for signs of toxicity such as severe diarrhea or neutropenia.

Multi-Racial Normative Data for Lobar and Subcortical Brain Volumes in Old Age: Korean and Caucasian Norms May Be Incompatible With Each Other†.

Brain aging is becoming an increasingly important topic, and the norms of brain structures are essential for diagnosing neurodegenerative diseases. However, previous studies of the aging brain have mostly focused on Caucasians, not East Asians. The aim of this paper was to examine ethnic differences in the aging process of brain structures or to determine to what extent ethnicity affects the normative values of lobar and subcortical volumes in clinically normal elderly and the diagnosis in multi-racial patients with Alzheimer's disease (AD). Lobar and subcortical volumes were measured using FreeSurfer from MRI data of 1,686 normal Koreans (age range 59–89) and 851 Caucasian, non-Hispanic subjects in the ADNI and OASIS datasets. The regression models were designed to predict brain volumes, including ethnicity, age, sex, intracranial volume (ICV), magnetic field strength (MFS), and MRI scanner manufacturers as independent variables. Ethnicity had a significant effect for all lobar (|β| > 0.20, p < 0.001) and subcortical regions (|β| > 0.08, p < 0.001) except left pallidus and bilateral ventricles. To demonstrate the validity of the z-score for AD diagnosis, 420 patients and 420 normal controls were selected evenly from the Korean and Caucasian datasets. The four validation groups divided by race and diagnosis were matched on age and sex using a propensity score matching. We analyzed whether and to what extent the ethnicity adjustment improved the diagnostic power of the logistic regression model that was built using the only z-scores of six regions: bilateral temporal cortices, hippocampi, and amygdalae. The performance of the classifier after ethnicity adjustment was significantly improved compared with the classifier before ethnicity adjustment (ΔAUC = 0.10, D = 7.80, p < 0.001; AUC comparison test using bootstrap). Korean AD dementia patients may not be classified by Caucasian norms of brain volumes because the brain regions vulnerable to AD dementia are bigger in normal Korean elderly peoples. Therefore, ethnicity is an essential factor in establishing normative data for regional volumes in brain aging and applying it to the diagnosis of neurodegenerative diseases.

A Phonological Study of North Korean defectors from Anak in the Hwanghae province

The purpose of this study is to analyze the freely spoken language of North Korean defectors from Anak, Hwanghae province using the Hwanghae-do dialect, and identify its phonological characteristics. The informants of this study acquired the language after the division of the Korean peninsula, so it is expected that they will show the characteristics of the modern Hwanghae-do dialect well. This data identified a total of 19 consonants. This is generally similar to the central dialect, but it is characteristic that /c/(ㅈ) is realized as alveolar. Eight simple vowels were also identified, but most of /&#1255;/(ㅚ) suggested in the existing Hwanghae-do dialect research was realized as [e] in this data. /&#601;/(ㅓ) > /&#616;/(ㅡ) high vowelization appeared in the word-initial and intervocalic, in the short vowels and long vowels, and in the lexical morphemes and grammatical morphemes. /e/(ㅔ) > /i/(ㅣ) has been identified limitedly in some words. Also, /o/(ㅗ) > /u/(ㅜ) appears in some parts of the lexical morphemes, and is overwhelmingly identified in the grammatical morphemes. Front-vowelization has a wider realization environment than Han Young-soon (1967). And in Kim Young-bae (1981), Anak is reported as a non-realized area of front-vowelization. However, in the speaker s speech, it appeared in a limited capacity. Umlaut was only partially identified within the morpheme and in derived words. The vowel harmony was as follows. First, in the case of the monosyllabic stems, the pattern was similar to the preceding Hwanghae-do dialect studies. However, in the case of the polysyllabic stems, numerous cases were found to differ from these studies. In addition, in the case of p-irregular stems, the pattern was similar to the Pyeongan-do dialect. The t-palatalization showed the same pattern as its general appearance in normal Korean. h-palatalization was confirmed only in ‘simdeulda’ (himdeulda, ‘to be hard’), and k-palatalization did not appear at all. Finally, The environment of h-deletion was ‘root + -hada(verb-derived suffix) and ‘noun + hago(case marker) . Even if the coda consonant in the root (or noun) is obstruent, ‘h is usually deleted. The items covered in this study can be classified into three broad categories. The first is that which appears in both dialects. This is high vowelization, umlaut, and h-deletion. The second is maintaining the characteristics of the Hwanghae-do dialect. This includes the list of consonants, the place of articulation of /c/(ㅈ), and the t-palatation. This has long been the decisive criterion for distinguishing the Hwanghae-do dialect from the Pyeongan-do dialect. Because of this, Hwanghae-do dialect speakers could not easily accept the characteristics of the Pyeongan-do dialect. On the other hand, since there has been a tendency to pronounce /c/(ㅈ) as a phoneme in the Pyeongan-do dialect, it can be interpreted that speakers of the Hwanghae-do dialect did not accept the old form. Finally, there are certain aspects of the language that were influenced by the dialect of Pyeongan province. This includes a simple vowel list, front-vowelization, vowel harmony, h-palatalization, and k-palatalization. Unlike Hwang Dae-hwa (2007), these items appear in a very limited amount in this research. The speakers have a negative attitude toward these dialects, which can be understood as the acceptance of the Pyeongan-do dialect.

Analysis of Factors Affecting Corneal Deflection Amplitude in Normal Korean Eyes

Analysis of Factors Affecting Corneal Deflection Amplitude in Normal Korean Eyes

Bruch's Membrane Minimum Rim Width in a Normal Korean Population

Bruch's Membrane Minimum Rim Width in a Normal Korean Population

Association of HK2 and NCK2 with normal-tension glaucoma in a population from the Republic of Korea.

Previous studies have reported the association of HK2 and NCK2 genes with normal-tension glaucoma (NTG) in Japan, but there has been no follow-up study in other countries, so the relevance of these genes to NTG appears uncertain at present. Thus, we investigated the relationship between the HK2 and NCK2 genes and NTG in a Korean NTG cohort. In total, 154 unrelated Korean patients with NTG and 101 normal Korean controls were recruited. Thus, a total of 255 participants were analyzed for NCK2 (rs2033008) and HK2 (rs678350) gene polymorphisms. The minor allele frequency (MAF) of rs678350 was significantly higher in NTG patients (MAF = 0.32) than in controls (MAF = 0.23) (OR, 1.586; 95% CI, 1.058 to 2.375; P = 0.028). This trend was more significant in the dominant model (OR, 1.908; 95% CI, 1.144 to 3.180; P = 0.015). When we performed logistic regression analysis to adjust for age, both the allelic and dominant models were still statistically significant. No significant difference was observed in rs2033008 allele or genotype frequencies between the NTG patients and control subjects. The current study suggested that HK2 gene polymorphism may contribute to the genetic susceptibility to NTG.

Developmental Trajectories of Attention in Normal Korean Population.

Objectives:This study aimed to investigate the trajectory of change of diverse attention and working memory in Koreans from 4 to 40 years of age.Methods:The data of 912 subjects from 4 to 15 years of age obtained from a previous standardization study of the computerized comprehensive attention test were merged with the newly obtained data of 150 subjects aged 16 to 40 years from this study. We evaluated the various kinds of attention, in which each subtest had five indicators. Working memory, with parameters such as number of correct responses and span, was also measured.Results:Our findings indicated that attention developed as age increased, and it decreased or was maintained after a certain age. Selective and sustained attention developed rapidly in children and adolescents, until mid-teens or 20 s when it ceased development. Divided attention, however, developed up to approximately age 20. In addition, working memory developed until mid-teens or 20 s.Conclusion:We presented the standardized data on diverse kinds of attention and working memory in children, adolescents, and adults in Korea. We could recognize any patterns of change in attention and working memory with increasing age.

Normal Korean Femoral Neck Anteversion, Acetabular Anteversion and Combined Anteversion Measured with Computed Tomography

Normal Korean Femoral Neck Anteversion, Acetabular Anteversion and Combined Anteversion Measured with Computed Tomography

Diurnal Variation of the Choroid in Normal Korean Subjects

Diurnal Variation of the Choroid in Normal Korean Subjects

Characteristics of Speech Intelligibility and Speech Acceptability Connected with Interdentalized /s, s*/

Purpose The purpose of this study was to compare the scores of speech intelligibility and speech acceptability in normal and interdentalized Korean fricative /s, s*/ in word and sentence level. Methods 36 words with /s, s*/ sounds and 10 sentences with /s, s*/ sounds words were recorded by two women with R-05 Wave/MP3 Recorder (Roland). After listening the normal and interdentalized /s, s*/ words and sentences, 54 female undergraduate students scored the speech intelligibility and speech acceptability. Results The scores of speech intelligibility and speech acceptability in interdentalized /s, s*/ words and sentences were significantly lower than the scores of those in normal Korean /s, s*/ words and sentences. And the scores of speech acceptability were significantly lower than those of speech intelligibility in interdentalized /s, s*/ words and sentences. Conclusion These results showed that the general female undergraduate students were impressed the words and sentences with interdentalized /s, s*/ were less intelligible and less acceptable rather than normal /s, s*/ words and sentences. These results can be applied to diagnosis and treatment of subjects with interdentalized fricative /s, s*/ in Korean. Key Words: Interdentalized Korean fricative, Speech intelligibility, Speech acceptability 중심 단어: 치간음화, 말 ëª ë£Œë„, 말 용인도

Comparison of Hand–Grip Strength Between Normal Korean Adults and Those with Type 2 Diabetes: 2014-2015 Korea National Health and Nutrition Examination Survey

Comparison of Hand–Grip Strength Between Normal Korean Adults and Those with Type 2 Diabetes: 2014-2015 Korea National Health and Nutrition Examination Survey

Comparison of Cardiac Size and Cardiac Thoracic Ratio in Pregnant and Non-pregnant Women of Normal Korean Women Using Chest X-ray

Comparison of Cardiac Size and Cardiac Thoracic Ratio in Pregnant and Non-pregnant Women of Normal Korean Women Using Chest X-ray

Radiologic Prevalence and Features of Metacarpal Pseudoepiphysis on Normal Korean Children

Radiologic Prevalence and Features of Metacarpal Pseudoepiphysis on Normal Korean Children

3·1운동의 기폭제 : 여운형이 크레인에게 보낸 편지 및 청원서

Lyuh, Woon-hyung(1886~1947), a Korean politician, met an American politician Charles R. Crane(1869~1958) at the Carlton Cafe, Shanghai, on November 27, 1918. Crane was known as a personal friend and de-facto representative of President Woodrow Wilson instructed to investigate the actual situation in the Far East following World War I. Chinese people hailed Crane’s visit and were excited at his suggestion of sending Chinese representatives to the Paris Peace Conference in order to protect China’s interests. Inspired by Crane’s speeches, Lyuh asked him to transmit a Korean petition for liberation from Japanese rule to President Wilson. Lyuh’s petition to President Wilson, dated November 28, 1918, and his letter to Crane, dated November 29, 1918, were found in the Crane Family Papers archived in the Columbia University Library. Another copy was sent to Thomas F. Millard, the publisher of Millard’s Review of the Far East in Shanghai, to convey to the Paris Peace Conference. However, there is no evidence that Crane or Millard conveyed Lyuh’s petition to either President Wilson or the Paris Peace Conference.BR Lyuh established the New Korean Young Men’s Association with his colleagues in Shanghai to solve the representation problem. He invited Kim Kyu-sik to Shanghai and sent him as an official representative of the New Korean Young Men’s Association to the Paris Peace Conference. Lyuh’s petition to President Wilson and his sending Kim to Paris became a crucial motivation for the outburst of the March First Movement of 1919. Lyuh and Kim were normal Korean residents in China, but their roles in Shanghai and Paris turned them into key figures in the Korean independence movement during and after the March First Movement.