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Dive into the research topics where Yoshiaki Ogura is active.

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Featured researches published by Yoshiaki Ogura.


Forensic Science International | 1995

Cardiac lesions and their reversibility after long term administration of methamphetamine.

Mohammed Nasimul Islam; Hisanaga Kuroki; Bai Hongcheng; Yoshiaki Ogura; Naomasa Kawaguchi; Shunzo Onishi; Choei Wakasugi

In order to clarify the effect of methamphetamine (MA) on myocardium, histological, immunohistochemical and electron microscopic changes in the myocardium of rats were examined following daily intraperitoneal administration of MA at a dose of 1 mg per kg body weight for 4, 8, and 12 weeks before sacrifice. Normal saline (NS) was similarly injected for the same period before sacrifice to constitute a control group. Light microscopic changes found in the myocardium of the MA-treated group included atrophy, hypertrophy, patchy cellular infiltration, eosinophilic degeneration and disarray, edema myolysis, fibrosis, and the appearance of vacuoles. Ultrastructurally, nuclei and normal mitochondria had various shapes and there were dilated T tubules and sarcoplasmic reticulum, the accumulation of glycogen granules and fat droplets. Intra- and extra-cellular edema and intramyocytic vacuoles were often found. Withdrawal of MA at the twelfth week in another group of rats evidenced gradual recovery of the myocardial changes, commencing at 3 weeks after withdrawal. Optimism is therefore generated about the possibility of the affected hearts in MA-abuse patients returning towards the normal state if they give up the drug.


Journal of Forensic Sciences | 1999

Simultaneous detection of multiple STR loci on sex chromosomes for forensic testing of sex and identity

Zaw Tun; Katsuya Honda; Masato Nakatome; Masami Nakamura; Shigeko Shimada; Yoshiaki Ogura; Hisanaga Kuroki; Motohiko Yamazaki; Masaru Terada; Ryoji Matoba

The forensic usefulness of X and Y chromosomal STR loci has recently been demonstrated. One quadruplex-PCR, using 2 X- and 2 Y-STRs (STRX1/HPRTB and DYS390/ DYS393), and 2 duplex-PCRs, each using an X- and a Y-STR (ARA/DYS390 and ARA/DYS393), and detection of PCR products by using an automated DNA sequencer are reported herein. This approach allows us to determine not only the sex of the donor of a sample, but also the X- and/or Y-STR genotypes of the sample. A male biological specimen yields 4 amplified products in quadruplex-PCR and 2 amplified fragments in duplex-PCRs, whereas a female biological specimen yields only 2 amplified fragments of X-STR in quadruplex-PCR and one fragment, also of X-STR, in duplex-PCRs. Our study thus provides useful information for many activities in forensic practice, such as identity testing, paternity testing, especially of deficiency cases, compilation of population data, and sex determination of a biological sample from a single PCR.


International Journal of Legal Medicine | 2002

Detection of cardiomyocyte apoptosis in forensic autopsy cases

Masato Nakatome; Ryoji Matoba; Yoshiaki Ogura; Zaw Tun; Mineo Iwasa; Yoshitaka Maeno; Hiroyoshi Koyama; Y. Nakamura; Hiroyuki Inoue

Abstract The purpose of the present study was to determine reliable parameters for the detection of apoptotic cells for use as a diagnostic marker during the early stage of acute myocardial infarction (AMI) in forensic autopsy cases. Myocardial tissues taken from forensic autopsy cases were examined by immunohistochemical and molecular-biological methods using the terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end-labelling (TUNEL) and the DNA laddering methods. In cases of AMI with a time period between 2 h from onset to death and 20 h post-mortem time, the nuclei of cardiomyocytes were stained positive with the TUNEL method and DNA fragmentation of myocardial cells was detected by agarose gel electrophoresis. Similar findings were obtained in cases of carbon monoxide (CO) intoxication. However, no apoptotic cells were found in other cases such as methamphetamine (MAP) intoxication, tetrodotoxin intoxication, alcohol intoxication, asphyxia, head injury, heart injury or myocarditis. These findings suggested that it would be possible to apply TUNEL-positive cells as a diagnostic marker during the early stages of AMI.


Forensic Science International | 1992

Myocardial lesions induced after trauma and treatment

Ken-ichi Yoshida; Yoshiaki Ogura; Choei Wakasugi

In order to clarify the effect of trauma and treatment as stresses on myocardia, we examined histological changes of myocardia in victims who received various kinds of traumata and treatments. We also undertook a histochemical study for calmodulin, which we found useful in the diagnosis of early ischemia. Those who died shortly after stab wounds, traffic accident or head injuries, showed mild cardiac lesions such as contraction bands or fragmentation and mild diffusion of calmodulin, a marker for necrosis. A case with hemorrhagic shock after a traffic accident, involving intense resuscitation for 2 h, showed severe cardiac lesions such as contraction bands, hydropic change and subendocardial hemorrhage along with severe diffusion of calmodulin. In most of the instant death cases after falls, severe contraction band necrosis and severe calmodulin diffusion were observed. Myocardia of victims, who died several days after head injuries or traffic accidents, generally demonstrated distinct diffusion of calmodulin as compared to the mild and non-specific lesions detected by hematoxylin-eosin (H&E) staining. In cases of long-term survival in a state of brain death, calmodulin staining was very low, which was not always associated with the severity of the lesions on H&E staining. In cases with intensive or extended treatment, it appeared to be difficult to determine the cause-effect relationship between trauma and cardiac lesions or to distinguish the lesions due to extrinsic factors from those of disease. In some cases, calmodulin intensely stained the areas with hydropic appearance or hypereosinophilia, which may be related to calcium overload.


Journal of Forensic Sciences | 1996

Rapid and clear detection of ABO genotypes by simultaneous PCR-RFLP method.

Zaw Tun; Katsuya Honda; Masato Nakatome; Mohammed Nasimul Islam; H. Bai; Yoshiaki Ogura; Hisanaga Kuroki; Motohiko Yamazaki; Masaru Terada; Choei Wakasugi

We reported a new approach of ABO genotyping by a polymerase chain reaction and restriction fragment length polymorphism method. Instead of amplifying the loci containing the positions of nucleotides 258 and 700 of cDNA of the A transferase separately, we successfully amplified these 2 loci together in one reaction mixture using 2 sets of primers. The amplified DNA products were digested at the same time with restriction enzymes Kpn I and Alu I. The digested DNA products were then separated by electrophoresis on polyacrylamide gel. In addition, we evaluated the influence of various amplification parameters (concentration of template DNA, primers, Taq DNA polymerase, MgCl2, and number of cycles). In particular, high Mg2+ concentration (3.5 mM) made effective amplification of this locus without producing any unspecific band. By using that optimized condition for PCR, together with a simultaneous approach, our study proved to be time saving, more economic, and convenient in interpreting the results.


Journal of Forensic Sciences | 1997

An electrocution death of an infant who had received an electric shock from an uncovered oval shaped lamp switch in his mouth while in a hospital

Motohiko Yamazaki; H. Bai; Zaw Tun; Yoshiaki Ogura; Choei Wakasugi

A male infant aged one year and nine months was found dead on a bed after admission to hospital with suspected pneumonia. The patient apparently put an uncovered oval shaped lamp switch (pendant switch) into his mouth and died of electric shock after contacting the exposed wires of the switch (100 V, 60 Hz alternating current). There were extensive first- to fourth-degree burns on the inner surface of the both lips. Because the histological findings were consistent with electric burns and the burns showed vital reactions, electric shock was judged to be the cause of death. The pendant switch is normally a very convenient piece of bedside equipment for inpatients. However, when the patient is an infant who naturally puts all the objects into the mouth, such a switch should be placed out of reach, and it should be certain that the cap is not loose.


Journal of Forensic Sciences | 1995

Detection of D1S80 (pMCT118) locus polymorphism using semi-nested polymerase chain reaction in skeletal remains

Katsuya Honda; Masato Nakatome; Mohammed Nasimul Islam; H. Bai; Yoshiaki Ogura; Hisanaga Kuroki; Motohiko Yamazaki; Masaru Terada; Shogo Misawa; Choei Wakasugi

We evaluated the usefulness of a semi-nested polymerase chain reaction (PCR) method for detecting D1S80 (pMCT118) locus polymorphisms of DNA extracted from old skeletal remains. The semi-nested PCR has been applied to the amplification of D1S80 nucleic acid sequences. For amplification of the locus D1S80, a pair of oligonucleotide primers have been used widely as described by Kasai et al. We have designed another set of primers for semi-nested PCR. This method resulted in D1S80-VNTR detection from low-titered DNA isolated from old skeletal remains. The first and second step PCR achieved amplification from as little as 10 ng and 10 pg of template DNA, respectively. Specificity and sensitivity of the amplification products was markedly improved by semi-nested PCR. In DNA extracted from biological samples, this method took about 5 hours to amplify the target DNA and 3 hours for electrophoretic separation. We demonstrated that this semi-nested PCR method was superior in sensitivity to conventional 1-step standard amplification for VNTR typing of the D1S80 locus.


Legal Medicine | 2009

A case of diffuse axonal injury in violent death

Kaori Mochizuki; Hiroshi Ochi; Yoshiaki Ogura; Morio Iino; Hisanaga Kuroki; Ryoji Matoba

A 59-year-old man was carried to the hospital by three men. The deceased was unconscious at admission and his face was severely swollen with many subcutaneous hemorrhages and extensive edema. His death was confirmed 17 min after resuscitation. A judicial autopsy was performed the next day. Findings showed that the victims face and head were reddish and swollen, and that subscalp bleeding was ubiquitous, but no skull fracture, epi- and subdural hematoma or subarachnoidal bleeding was observed. The brain itself was severely edematous but no bleeding was found. Although small hemorrhages were seen in the limbs and back, there were no marked wounds except to the head. To determine the cause of death, we performed a microscopic histochemical examination. Conventional H.E. staining disclosed eosinophilic change, concentration of nuclei, edema, gliosis, and oozing at the corpus callosum. To identify further details of the cause of death, we used Bodian staining, Kluver-Barrera staining, anti-beta amyloid immunostaining, and anti-neurofilament immunostaining. We found sinusoidal swelling of axons and waving axons, which are typical findings of Diffuse Axonal Injury (DAI), but no positive staining of beta amyloid. Focal lesions of the corpus callosum and of the dorsolateral quadrant of the rostral brain stem, and diffuse damage to axons are considered to constitute the DAI triad. We therefore diagnosed the cause of death as DAI. Our experience shows that it is important to use several staining methods for diagnosis of a variety of neuronal degenerative disorders. Several days later, we were informed by the police that several men had hit and kicked the victim in an attempt to lynch him. To compare with this case, we also report two other cases in which DAI was observed.


Archive | 1996

Detection of Sequence Variants in Hypervariable Segments of Mitochondrial DNA in the Asian Population

Katsuya Honda; Masato Nakatome; S. Harihara; Zaw Tun; Mohammed Nasimul Islam; H. Bai; Yoshiaki Ogura; Hisanaga Kuroki; Motohiko Yamazaki; Masaru Terada; Shogo Misawa; Choei Wakasugi

The analysis of highly polymorphic regions of mitochondrial DNA is one of the most commonly used methods for personal identification. The recent advances of fluorescent detection in automated DNA sequencing (Smith et al. 1986) has made it possible a rapid analysis of sequence variants without using isotopic labeling.


International Journal of Legal Medicine | 1995

Amplification and detection of the VNTR locus D4S95 in a Japanese population

Katsuya Honda; Masato Nakatome; Mohammed Nasimul Islam; H. Bai; Yoshiaki Ogura; Hisanaga Kuroki; Motohiko Yamazaki; Masaru Terada; Choei Wakasugi

The D4S95-VNTR locus was amplified and the polymorphism analysed in a population sample of 169 randomly selected Japanese individuals. A total of 14 alleles containing 850–1360 base pairs were distinguished by agarose gel electrophoresis. The distribution of alleles was symmetrical with respect to one peak at 1030 bp. The mean exclusion chance and discrimination power were calculated as 0.604 and 0.876 respectively.

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