Sudden infant death syndrome in Korea: a retrospective analysis of autopsy-diagnosed cases.

This study aimed to elucidate the demographic and sleeping environmental factors associated with sudden infant death syndrome (SIDS) in Korea. The autopsy reports of all SIDS cases reported to the National Forensic Service and Seoul National University College of Medicine between 1996 and 2008 were reviewed for data collection and analysis to identify the risk factors for SIDS. Analysis of the 355 SIDS cases reported within the study period revealed that of the 168 (47.3%) cases for which sleeping position before death had been reported, 75 (44.7%) cases had occurred after placement in prone or side position. Of the 204 (57.5%) cases for which bed-sharing situation had been reported, 121 (59.3%) deaths had occurred during bed-sharing, of which 54 (44.6%) infants were under 3 months of age, a significantly younger age than that of the non-bed-sharing cases (P = 0.0279). Analysis of the results indicated no tendency toward an increase or decrease in the use of a prone or side position. Rather, there was a statistically significant increasing trend for bed-sharing over the study period (OR, 1.087; 95% CI, 1.004-1.177; P = 0.04). These findings indicate the need for nationwide educational programs promoting a safe sleeping environment to enhance SIDS prevention.

Epigenetic changes in estrogen receptor beta gene in atherosclerotic cardiovascular tissues and in-vitro vascular senescence.

Epigenetic changes marked by DNA methylation have been proposed to play a role in age-related disease. We investigated DNA methylation changes in cardiovascular atherosclerotic tissues and in-vitro vascular senescence in the promoter of estrogen receptor beta gene, which has essential roles in vascular function. Coronary atherosclerotic tissues showed higher methylation levels (28.7%) than normal appearing arterial (6.7%-10.1%) and venous tissues (18.2%). In comparing estrogen receptor beta methylation between plaque and non-plaque regions in ascending aorta, common carotid artery, and femoral artery of two patients, the plaque lesions showed consistently higher methylation levels than non-plaque regions. Passage-dependent increased estrogen receptor beta methylation was observed in three of six human aortic endothelial or smooth muscle cell lines cultured in-vitro to vascular senescence. Estrogen receptor beta expression in these vascular cell lines was significantly activated by DNA-methyltransferase inhibition. This activity was augmented by histone deacetylase inhibition. These findings provide evidence of epigenetic dysregulation of estrogen receptor beta in atherosclerosis and vascular aging. We suggest that focal epigenetic changes in estrogen receptor beta contribute to the development of atherosclerosis and vascular aging.

Population database on nine STR loci of the AmpFlSTR Profiler kit in Koreans.

Allele frequencies for nine STR loci included in the AmpFlSTR Profiler Kit (D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317 and D7S820), were obtained from a sample of 1206 unrelated individuals living in the central region of Korea.

Investigation of bleeding focus in the intracranial vertebral artery with the use of posterior neck dissection method in traumatic basal subarachnoid hemorrhage.

Traumatic basal subarachnoid hemorrhage caused by minor blunt trauma to the head or neck can lead to rapid collapse and death. The vertebral arteries are the vessels most commonly involved in such cases, but it is very difficult to find the bleeding focus in the vertebral arteries in routine autopsy because of the location of these vessels. Using the posterior neck dissection method, which is relatively easy and avoids artificial damage to the intracranial portion of the vertebral arteries, authors have identified tear sites in the intracranial artery in four out of five consecutive traumatic basal subarachnoid hemorrhage cases. In this report we show that this new method is useful for cases of traumatic basal subarachnoid hemorrhage.

Postmortem mRNA expression patterns in left ventricular myocardial tissues and their implications for forensic diagnosis of sudden cardiac death.

Sudden cardiac death (SCD), which is primarily caused by lethal heart disorders resulting in structural and arrhythmogenic abnormalities, is one of the prevalent modes of death in most developed countries. Myocardial ischemia, mainly due to coronary artery disease, is the most common type of heart disease leading to SCD. However, postmortem diagnosis of SCD is frequently complicated by obscure histological evidence. Here, we show that certain mRNA species, namely those encoding hemoglobin A1/2 and B (Hba1/2 and Hbb, respectively) as well as pyruvate dehydrogenase kinase 4 (Pdk4), exhibit distinct postmortem expression patterns in the left ventricular free wall of SCD subjects when compared with their expression patterns in the corresponding tissues from control subjects with non-cardiac causes of death. Hba1/2 and Hbb mRNA expression levels were higher in ischemic SCD cases with acute myocardial infarction or ischemic heart disease without recent infarction, and even in cardiac death subjects without apparent pathological signs of heart injuries, than control subjects. By contrast, Pdk4 mRNA was expressed at lower levels in SCD subjects. In conclusion, we found that altered myocardial Hba1/2, Hbb, and Pdk4 mRNA expression patterns can be employed as molecular signatures of fatal cardiac dysfunction to forensically implicate SCD as the primary cause of death.

Quantitative analyses of postmortem heat shock protein mRNA profiles in the occipital lobes of human cerebral cortices: implications in cause of death.

Quantitative RNA analyses of autopsy materials to diagnose the cause and mechanism of death are challenging tasks in the field of forensic molecular pathology. Alterations in mRNA profiles can be induced by cellular stress responses during supravital reactions as well as by lethal insults at the time of death. Here, we demonstrate that several gene transcripts encoding heat shock proteins (HSPs), a gene family primarily responsible for cellular stress responses, can be differentially expressed in the occipital region of postmortem human cerebral cortices with regard to the cause of death. HSPA2 mRNA levels were higher in subjects who died due to mechanical asphyxiation (ASP), compared with those who died by traumatic injury (TI). By contrast, HSPA7 and A13 gene transcripts were much higher in the TI group than in the ASP and sudden cardiac death (SCD) groups. More importantly, relative abundances between such HSP mRNA species exhibit a stronger correlation to, and thus provide more discriminative information on, the death process than does routine normalization to a housekeeping gene. Therefore, the present study proposes alterations in HSP mRNA composition in the occipital lobe as potential forensic biological markers, which may implicate the cause and process of death.

Validity of Demirjian's and modified Demirjian's methods in age estimation for Korean juveniles and adolescents.

In estimating age of juveniles and adolescents, the teeth are employed primarily because of its low variability and less affection by endocrine and nutritional status in development. Demirjian established criteria for evaluating maturity of teeth and his method has been used throughout the world. However, several studies showed the inappropriateness of Demirjian's method on populations other than the one it is based on. Consequently some researchers modified Demirjian's method using data of several different populations. Demirjian himself also published a revised method to overcome other shortcomings of his original method. The aim of this study was to test the validity of Demirjian's and the modified methods (Demirjian's revised, Willems', Chaillet's and new Korean methods) for Korean juveniles and adolescents. 1483 digital orthopantomograms which consist of 754 males and 729 females in the age range of 3-16 years were collected. New age estimation method based on Korean population data was calculated. Dental age was estimated according to each method and the validity was evaluated using the differences between chronological and dental age. The inter- and intra-observer reliability was evaluated to be excellent. Statistically significant difference was observed between chronological and dental age in all the methods for both sexes except new Korean method for both sexes and Demirjian's revised method for males. However, when analyzing absolute and squared value of difference, Willems' method was found to be most accurate followed by new Korean method with slight difference for Korean population for both sexes. In conclusion, both Willems' method and new Korean method conducted by present study were proven to be suitable for Korean population.

Utility of postmortem autopsy via whole-body imaging: initial observations comparing MDCT and 3.0 T MRI findings with autopsy findings.

OBJECTIVE: We prospectively compared whole-body multidetector computed tomography (MDCT) and 3.0 T magnetic resonance (MR) images with autopsy findings. MATERIALS AND METHODS: Five cadavers were subjected to whole-body, 16-channel MDCT and 3.0 T MR imaging within two hours before an autopsy. A radiologist classified the MDCT and 3.0 T MRI findings into major and minor findings, which were compared with autopsy findings. RESULTS: Most of the imaging findings, pertaining to head and neck, heart and vascular, chest, abdomen, spine, and musculoskeletal lesions, corresponded to autopsy findings. The causes of death that were determined on the bases of MDCT and 3.0 T MRI findings were consistent with the autopsy findings in four of five cases. CT was useful in diagnosing fatal hemorrhage and pneumothorax, as well as determining the shapes and characteristics of the fractures and the direction of external force. MRI was effective in evaluating and tracing the route of a metallic object, soft tissue lesions, chronicity of hemorrhage, and bone bruises. CONCLUSION: A postmortem MDCT combined with MRI is a potentially powerful tool, providing noninvasive and objective measurements for forensic investigations.

Quantitative analysis of aortic atherosclerosis in Korean female: a necropsy study.

To assess the regional difference and influence of the biological variables on atherosclerosis in female, we analyzed 7 segments of aorta (2 ascending, 3 thoracic, and 2 abdominal) from 90 superficially healthy Korean women (39+/-14 yr of age) who died from external causes. Tissue specimens were macroscopically examined and histopathologically divided into 7 grades for scoring (ATHERO, from 0=intact, to 6=thrombi formation). Lumen diameter (LD), wall thickness (WT), intima thickness (INT), and media thickness (MED) were obtained by computed morphometry. Atherosclerosis was common in the distal infrarenal (C2), proximal thoracic (B1), and proximal ascending (A1) segments. Total 95.6% of all subjects had atherosclerosis of variable degree in one or more segments, but an aneurysmal change was not found. The number of atherosclerotic segments and atherosclerosis score in the 7 segments increased with aging. However, the body size did not affect the aortic size and ATHERO. With aging, LD and INT of the A1, B1 and C2 increased (p<.00001); WT of the B1 and C2 increased (p<.01); and MED of C2 decreased (p<.01). LD and WT of the B1 and C2 (p<.05), INT of the A1, B1 and C2 (p<.00001) increased, and MED of C2 decreased (p<.01) with ATHERO. These data suggest that age is simple but a reliable parameter for estimating the progression of atherosclerosis.