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Biomedical subjects

Kentaro Yamazaki

Publications and source records attributed to Kentaro Yamazaki.

25 records · Page 2Linked to original sources

The specific mitochondrial DNA polymorphism found in Klinefelter's syndrome.

Hypervariable segments of mitochondrial DNA (mtDNA) (HV1 and HV2) were analyzed in Klinefelter's syndrome and compared to normal population data. One pair of samples consisting of a Japanese mother and affected son with Klinefelter's syndrome (involved in a criminal case), and seven unrelated DNA samples from Caucasian Klinefelter males (two involved in criminal cases and five diagnosed) were collected in Japan and the United States. The diagnosis of Klinefelter's syndrome was established previously by multiplex XY-STR typing detecting two X alleles and one Y allele in the samples. Haplotype analysis of the mtDNA sequence in Klinefelter males was found to be identical, unique, and specific, as it was not found in the normal population. Astonishingly, family data exhibited that the haplotype of the mtDNA in the son was apparently different from the mother's, suggesting that the mtDNA of Klinefelter male would not be inherited from mother to son. Our data indicate that possible interaction of the sex chromosome and the mtDNA exists, and suggests that the specific mtDNA haplotype could cause the abnormal cell to fertilize and reproduce itself.

DNA, Mitochondrial↗

Carcinoma of duodenum arising from Brunner's gland.

Primary carcinoma of the duodenum is a rare lesion. In conjunction with the widespread use of panendoscopy, reported cases of carcinoma of the duodenum have recently increased. Although benign hyperplasia of Brunner's gland is well documented, duodenal carcinoma originating in Brunner's gland is extremely rare, and, consequently, there is little data on the morphological or histochemical characteristics. We report here a case of early duodenal carcinoma arising from Brunner's gland, whose origin was proven by mucin immunohistochemistry.

Adenocarcinoma↗

Estimation of postmortem interval from hypoxic inducible levels of vascular endothelial growth factor.

Estimation of the postmortem interval (PMI) is one of the most important tasks in forensic medicine. Five autopsy organ tissues such as brain, lungs, heart, liver, and kidneys were taken at the time of forensic autopsy from 19 known PMI cases with a range of postmortem intervals ranging from 1 to 120 h (the mean was 25.81 h), and the time-course of vascular endothelial growth factor (VEGF) expression was measured. The human hepatoma-derived Hep 3B cell line was used as a control. The levels of VEGF increased linearly with the PMI up to 20 h in lung (r = 0.95 and in kidney (r = 0.89), and up to 15 h PMI in liver (r = 0.88). The VEGF levels fell after 24 h PMI, and then remained stable. In brain, the levels of VEGF started to increase after 24 h PMI and increased linearly with PMI up to 40 h in brain (r = 0.94) and then begin to fall. In heart, there was no clear correlation between the PMI and VEGF level. Some variations occurred in selected cases, such as the infant and asphyxial deaths. In conclusion, measurement of hypoxia-inducible levels of VEGF in various body organs appears to be a useful method of estimating the PMI up to 24 h in forensic medicine and pathophysiology. This method is also probably applicable in ischaemia in clinical and basic medicine.

Carcinoma, Hepatocellular↗

Dilatation of the heart on postmortem computed tomography (PMCT): comparison with live CT.

PURPOSE: To delineate cardiac structures on postmortem computed tomography (PMCT) and quantitatively to prove dilatation of the heart after death. MATERIALS AND METHODS: Our subjects were 50 PMCT of non-traumatic deaths and 50 CT of living persons (live CT). We measured maximal and minimal diameters of the superior vena cava (SVC) at three levels (upper, middle, and lower), the inferior vena cava (IVC), pulmonary artery (PA), pulmonary vein (PV), right atrium (RA), and left atrium (LA). Then the product of maximal by minimal diameter and the eccentricity were calculated. RESULTS: The maximal and minimal diameters of the heart were significantly longer than those on live CT except for 1) the maximal diameter of the SVC at the upper level and 2) the maximal diameter of the PA. All of the products of maximal by minimal diameter on PMCT were significantly larger than those on live CT. All of the eccentricities decreased significantly after death except LA. CONCLUSION: The heart is dilated on PMCT, and the right side of it dilates toward a round shape.

Adult↗

Postmortem computed tomographic (PMCT) demonstration of the relation between gastrointestinal (GI) distension and hepatic portal venous gas (HPVG).

PURPOSE: The purpose of this study was to investigate the relation between gastrointestinal (GI) distension and hepatic portal venous gas (HPVG) on postmortem computed tomography (PMCT). MATERIALS AND METHODS: Our subjects were 190 PMCT obtained within two hours of non-traumatic death [175 patients underwent cardiopulmonary resuscitation (CPR) and 15 patients did not undergo CPR]. We evaluated the incidence and location of GI distension (0 = no distension, 1 = stomach and duodenum, 2 = more distal than 1) and HPVG (0 = no gas, 1 = left lobe, 2 = 1 + right anterior lobe, 3 = 2 + right posterior lobe). RESULTS: GI distension (grade 0/1/2 = 58/55/62 patients) and HPVG (grade 0/1/2/3 = 114/10/ 28/23 patients) were observed in 175 patients who underwent CPR. The grade of HPVG increased significantly in accordance with the advancement of GI distension. Fifteen patients without undergoing CPR showed no GI distension but one patient showed grade 1 HPVG. CONCLUSION: PMCT indicates the presence of a relation between GI distension and HPVG.

Adolescent↗

Postmortem computed tomographic (PMCT) demonstration of fatal hemoptysis by pulmonary tuberculosis--radiological-pathological correlation in a case of rupture of Rasmussen's aneurysm.

We report a case of fatal hemoptysis resulting from the rupture of a Rasmussen's aneurysm. Postmortem computed tomography (PMCT) clearly showed the air-fluid level within a tuberculous cavity and fluid-filled trachea. In this case, PMCT was useful as a screening tool to detect the cause of death as asphyxia from hemoptysis. It became a guideline for the following autopsy, as well as evidence to explain the importance of autopsy to the family.

Aneurysm, Ruptured↗

Postmortem computed tomographic (PMCT) findings of pericardial effusion due to acute aortic dissection.

PURPOSE: To describe the appearance of pericardial effusion in deceased acute aortic dissection patients using postmortem computed tomography (PMCT). MATERIALS AND METHODS: PMCT examinations were performed within 2 hours of death in 30 patients with pericardial effusion due to aortic dissection who arrived at our hospital in a state of cardiopulmonary arrest. RESULTS: Pericardial effusion in 18 of 30 patients (60%) showed double concentric rings on PMCT with striking differences in density, a low-density outer ring along the pericardium and a high-density inner ring on the epicardial surface (hyperdense armored heart). Pericardial effusion in two patients (7%) showed a high-density fluid level (hypostasis). Pericardial effusion in the remaining 10 patients (33%) showed no such stratification. CONCLUSION: A "hyperdense armored heart" is the most frequently seen PMCT finding in deceased cases of pericardial effusion due to acute aortic dissection.

Adult↗