An improved method for the diatom test utilizing DNA binding ability of silica.

In order to devise a better forensic test for diatoms, the DNA binding ability of the diatom frustule constructing by silica, in the presence of chaotropic ions were utilized. It was proved that the diatoms were able to be captured via λDNA using silica-coated magnetic beads (Mag beads), followed by isolation and purification from the Mag beads as a solid phase by substituting the chaotropic agent with ultrapure water. Five cases of drowning, three in freshwater and two in seawater, were applied to the present method and similar results as the usual diatom test were obtained.

A simple DNA coprecipitation method for the detection of diatoms in heart blood.

We developed a method for detecting and enumerating diatoms in the heart blood of drowning victims and evaluate its utility for diagnosing death by drowning. For purification of diatoms from blood, the DNA binding ability of the diatom frustule in the presence of a chaotropic agent was utilized. The procedure is basically the same as the commonly used method for DNA purification from blood using Proteinase K treatment and denaturation by a chaotropic agent.

STR and mitochondrial DNA SNP typing of a bone marrow transplant recipient after death in a fire.

Personal identification of a house fire victim is described. About 5 years prior to death, the victim had been underwent bone marrow transplantation (BMT) with a graft from an unrelated donor as treatment for acute myelogenous leukemia. Clinically, the victim had been in remission at the time of death.

Marine bacteria comprise a possible indicator of drowning in seawater.

To investigate the effectiveness of marine bacteria as a new marker of drowning in seawater, we determined the optimal conditions of media required to selectively detect marine bacteria and applied the technique to drowned cadavers. We incubated model blood samples (n=20 per group) mixed with seawater, river, tap or muddy water on agar plates (Todd Hewitt, TH; Marine 2216, M2216) and determined the NaCl concentration required to selectively detect marine bacteria. We also used TCBS agar plates without manipulation to isolate Vibrio spp.

Identification of DNA of human origin based on amplification of human-specific mitochondrial cytochrome b region.

Species-specific differences in a non-polymorphic region of the mitochondrial cytochrome b gene appear to be large enough to allow human-specific amplification of forensic DNA samples. We therefore developed a PCR-based method using newly designed primers to amplify a 157-bp portion of the human mitochondrial cytochrome b gene. The forward and reverse primers were designed to hybridize to regions of the human mitochondrial cytochrome b gene with sequences differing from those of chimpanzee by 26% (7 bp/27 bp) and 26% (6 bp/23 bp), respectively.

Establishment and characterization of a novel human pancreatic cancer cell line (SUIT-4) metastasizing to lymph nodes and lungs in nude mice.

A new tumor cell line (SUIT-4) derived from ascites of a patient with carcinoma of the pancreas has been established in tissue culture and in nude mice, and maintained for over 7 years. In tissue culture, the cells grew as a confluent monolayer with piling up of cells in some areas. The population doubling time during the exponential phase of the cell growth was 43.

A method for genotyping Y chromosome-linked DYS385a and DYS385b loci.

We developed a method for genotyping Y chromosome-linked homologous DYS385 loci individually, combining locus-specific polymerase chain reaction (PCR) amplification and previously reported procedures. Duplicated DYS385a (5'-end) and DYS385b (3'-end) loci were located about 41 kb apart and inverted to each other in the Y chromosome, which data was obtained from the human genome sequence in National Center for Biotechnology Information (NCBI), and sequence differences were found at 424 bp down- and upstream of each locus. The locus-specific amplifications were performed using primers designed for this intergenic region, and fragments about 900 bp in length were produced.

Mitochondrial DNA and STR typing of matter adhering to an earphone.

STR typing and mitochondrial DNA (mtDNA) sequencing were performed on the matter adhering to an earphone found at a crime scene. Experimental studies were carried out using the earphones provided by volunteers. By means of immunohistochemistry, keratinocytes and a portion of nucleated epithelial cells were proven to exist in the contents from the earphones.