A New Method for Sex Determination Based on Detection of SRY, STS and Amelogenin Gene Regions with Simultaneous Amplification of Their Homologous Sequences by a Multiplex PCR

We have developed a new method for sex determination based on simultaneous detection of the SRY (sex-determining region Y), STS (steroid sulfatase) and amelogenin (AMELX and AMELY) gene regions and their homologous sequences. The sex of 246 blood samples was correctly determined by this method. An AMELY-deleted male sample, which would have been erroneously considered female based solely on analysis of the amelogenin locus, was successfully identified as male by the present method. The detection limit of this method was 63 pg of genomic DNA, and the male DNA component could be detected from mixed samples having a male:female ratio as low as 1:10. This method was useful for degraded DNA and possessed the human specificity. Practical application to 35 autopsy cases is described

Postmortem Changes in Myoglobin Content in Organs

Postmortem changes in myoglobin concentrations in blood and organs were investigated using an enzyme immunoassay by animal experiments in combination with immunohistochemical staining of human cases. Blood myoglobin concentrations were found to increase drastically within a very short time after death. Those in striated muscle, however, did not change by day 14 postmortem. Myoglobin content in the liver and kidney increased slightly by day 5 postmortem, and more obviously by day 7 or later. However, almost no change was observed by day 5 in the kidney when the renal artery and vein had been ligated just after death. In the thyroid gland and the lung, the myoglobin content markedly increased by day 7 postmortem, with the logarithmical values rising nearly linearly as the time after death passed. In the thyroid gland, concentrations reached the level of the striated muscle. The mechanisms of postmortem myoglobin increase in organs are thought to be direct diffusion from the striated muscle and/or distribution through the blood. To estimate the postmortem interval, the determination of myoglobin content in the thyroid gland or the lung appears to be useful

Quantitative Analysis of DNA Degradation in the Dead Body

Postmortem degradation of DNA was quantitatively estimated. Brain, liver, kidney and muscle samples were obtained from sacrificed rats left at 20℃ or 4℃. The quantity of DNA was measured by real-time PCR using a primer set for a sequence in the Rsrc 1 gene. When the quantity of amplified DNA using 10ng Human Genomic DNA was defined as 100 RFU, the quantities in the brain, liver, kidney and skeletal muscle (each 2μg of dry weight) on the day of sacrifice were 253±11, 338±22, 556±14 and 531±12 Relative Fluorescence Units (RFU), respectively (mean±S.E., n＝5). The quantity of amplified DNA decreased to below 10 RFU in 1-3 weeks in the liver, kidney and skeletal muscle at 20℃, while that in the brain was more than 10 RFU for six weeks, demonstrating the usefulness of the brain as a sample for DNA analysis of decaying corpses. It was suggested that quantifying the amplified DNA in the brain at 20℃ and in the liver at 4℃ as well as the ratio of the quantity of amplified DNA in the liver to the brain at 4℃ might be useful for diagnosing time of death. This study provides the first quantitative analysis of the postmortem progress of DNA degradation in the corpse

Increase of S-100 protein-positive stellate cells in the anterior pituitary of chronic alcoholic patients with fatty liver or fatty cirrhosis.

Healthy subjects 40 years old were used as controls in a study of stellate cells (S-100 protein-containing cells, or S-100 cells) in subjects with chronic alcoholism and fatty liver or fatty cirrhosis. S-100 cells were sparsely found in the adenohypophysis of control subjects, and these cells sometimes formed small clusters. However, in chronic alcoholics with fatty liver or fatty cirrhosis, the number of stellate cells in the anterior pituitary tended to be 17 times higher than it was in the control group. No increase in the number of S-100 positive cells that constitute the large and small follicles in the intermediate pituitary. The physiological function of the S-100 protein has not yet been identified. The fact that an increase in prolactin-secreting and growth hormone-secreting cells, as well as a decrease in gonadotrophs were observed in the hypophysis of alcoholics suggests that the function of stellate cells may be closely related to these phenomena. Our results also imply that the stellate cells found in the anterior and intermediate pituitary differ in function although they both produce S-100 proteins.</p

Role of adenohypophyseal mixed cell-follicles in age estimation.

In this study we used paraffin-embedded human pituitary obtained from 248 autopsy cases and identified mixed cell follicles by the immunohistochemical method. We examined the number and size of the mixed cell follicles, and the ratio of each component cell of these follicles, in the anterior pituitary at various age groups. The number of follicles increased with age, and the size of the follicles also tended to enlarge with age. Statistical analysis showed that a high correlation existed between age and the number or the size of the mixed cell-follicles formed by various adenohypophyseal cells. In addition, when the proportions of the different cell types that formed the follicles were examined, sex differences were observed with aging for the GH cells, the PRL cells, and the gonadotroph (GTH) cells, while no changes were observed with aging in both men and women for the ACTH cells and TSH cells. These results indicate that the number, size, and ratio of each component cell of follicles in the anterior pituitary are adequately applicable for the purpose of age estimation in routine forensic medicine.</p

Haptoglobin genotyping by allele-specific polymerase chain reaction amplification

We performed haptoglobin (Hp) genotyping by polymerase chain reaction using allele-specific primer-pairs. The major six genotypes of Hp were identified using this method. Among Japanese individuals living in Ehime and Okayama Prefectures, the allele frequencies were estimated to be Hp2 = 0.723 and Hp1s = 0.277. Genotyping of Hp was possible with 0.3 ng of DNA and with 0.125 microliter of blood. It was also possible with whole blood left at room temperature for a month and also with the bloodstains left at room temperature for three years. In the heated blood samples, both alleles, Hp2 and Hp1s, were detected in those heated at 100 degrees C for 2 h. In bloodstains, Hp2 and Hp1s were detected in samples heated at 100 degrees C for 2 h and 120 degrees C for 30 min. In addition, the genotype could be detected in samples other than blood such as saliva, hair roots, tissue sections and dental pulps. The present method for Hp genotyping is expected to become a useful method in forensic analysis.</p

Age Estimation Using S-100 Protein-Positive Stellate Cells in Anterior Pituitary

We examined the embryonic development as well as postnatal development of S-100 protein-positive stellate cells in the anterior lobe of human hypophysis using immunohistochemical method, and investigated the possibility of using the frequency of the stellate cells for age estimation. A definite positive correlation was observed between the proportion of the stellate cell and age, in both males (r = 0.987) and females (r = 0.986). The linear regression equation was y = 0.206x - 1.82 for males and y = 0.239x - 2.22 for females (x: age, y: percentage of 5-100 protein-positive stellate cells). Although the reason for an increase in stellate cells with age remains unknown, the present results indicate that the proportion of stellate cells in the anterior pituitary can be applied reliably to estimate age

Unintentional Injury Deaths among Children: A Descriptive Study Using Medico-legal Documents in Okayama Prefecture, Japan (2001−2015)

According to the World Health Organization’s World Report, approx. 950,000 children and young people < 18 years old die from an injury each year, and unintentional injury deaths account for a large portion of these cases. Here we used medico-legal documents to epidemiologically analyze the cases of unintentional injury deaths among children < 5 years old in Okayama Prefecture, Japan from 2001 to 2015. Age, sex, manner/cause of death, and various circumstances of the incident were investigated. There were 73 unintentional injury deaths during the study period. Drowning (n=29), suffocation (n=24), and transport accidents (n=13) were the major categories of unintentional injury deaths. Twenty-two cases (30.1%) were autopsied. Differences in the characteristics of the unintentional injury deaths by age were observed. Information which cannot be obtained from Vital Statistics was available from medico-legal documents, and detailed characteristics of unintentional injury deaths among children < 5 years old were elucidated. Investigating medico-legal information is one of the meaningful measures for the prevention of unintentional injury deaths among children in Japan

Factors affecting the choice of suicide method in Okayama: a database analysis from a forensic perspective

The annual number of suicides in Japan increased sharply in 1998, and since that time it has consistently exceeded 30,000 per year. In this study, we analyze a database of personal and background characteristics of 824 cases (605 men, 219 women) who completed suicide in Okayama Prefecture in 2002 and 2003. The data were obtained with cooperation from the police. Using the methodologies in a previous European study as a model, we classified the suicide methods into 8 categories. To examine the generational and regional differences in the choice of methods, we stratified the sample into 4 age groups (&#60;-24, 2544, 4564, and &#62;-65) and 2 regional groups (Okayama/Kurashiki vs. other areas). Our results on gender differences in 7 of the suicide methods were mostly similar to the European data. However, our data showed a remarkably higher proportionate male-to-female mortality ratio for poisoning by other substances (ICD-10, X65-X69 codes) (1.83, 1.15-2.92). In terms of generational differences in the choice of suicide methods, the Mantel-Haenszel test of homogeneity was significant for most of the categories in our study, suggesting an impact of age on how people commit suicide. There were no remarkable regional differences in our sample. An epidemic curve for suicides via carbon monoxide poisoning using charcoal briquets revealed a trend of time clustering not observed in the other 6 means. The database constructed and used in this study contains richer information than conventional death statistics and is expected to provide helpful knowledge and insights for future epidemiological studies.</p