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K Iwadate

Publications and source records attributed to K Iwadate.

32 records · Page 2Linked to original sources
PubMed1996

Superoxide anion reduces the ability of myeloperoxidase to damage lipids.

The aim of this study was to determine whether lipids are damaged by myeloperoxidase (MP) not only with hydrogen peroxide (H2O2), but also with a H2O2-generating system. Using the hypoxanthine-xanthine oxidase-Cu,Zn-superoxide dismutase (HX-XO-SOD) system as an effective H2O2-generating system, we observed a reduction in the ability of MP to produce peroxylipids in the HX-XO-SOD-MP system, compared with the H2O2-MP system. We also noted that MP inhibited the production of monoepoxide by the H2O2-cytochrome c (Cyt c) system. These results suggest that MP plays a role as an absorber of active oxygen species and prevents phagocytes from self-destruction.

Cytochrome c Group↗
PubMed1995

Establishment of a monoepoxide (leukotoxin and its isomer) producing system using a hydrogen peroxide-generating system.

We established an effective monoepoxide-generating system by combining cytochrome-c (Cyt-c) with a hydrogen peroxide (H2O2)-generating system comprising hypoxanthine (HX), xanthine oxidase (XO) and superoxide dismutase (SOD; HX-XO-SOD-Cyt-c system). Using this and the H2O2-Cyt-c system, we proved that monoepoxide production from linoleic acid was due to hydroxy radical formation by the reaction of Cyt-c with H2O2 and not to the formation of other active oxygen species.

Benzoates↗
PubMed1995

pH dependent alterations of monoepoxides and monochlorohydrins of linoleic acid, and their existence in vivo.

Some monoepoxides of linoleic acid (LA) were converted to monochlorohydrins in low-pH solutions containing chloride ions (Cl-). Conversely, monochlorohydrins of LA were converted to monoepoxides in high-pH solutions. We attempted to determine whether these monochlorohydrins and monoepoxides were produced from LA by the cytochrome-c-H2O2-and/or myeloperoxidase-H2O2-system. The existence of monoepoxides and monochlorohydrins of LA in leukocytes was confirmed by high-performance liquid chromatography (HPLC). Furthermore, leukotoxin in human leukemia cells (THP-1) was stained immunohistochemically by a monoclonal anti-leukotoxin antibody.

Animals↗
PubMed1995

Immunohistochemical dynamics of leukotoxin (9,10-epoxy-12-octadecenoic acid) in lungs of rats.

This paper investigates the immunohistochemical dynamics of leukotoxin (9,10-epoxy-12-octadecenoic acid, LTx) in the lungs of rats exposed to hyperoxia with or without paraquat. The rats were treated with 100% oxygen or ambient air for 24, 48, 72 and 96 h in the presence or absence of a low or high dose paraquat (1,1'-dimethyl-4,4'-bipyridinium, PQ) injection. Immunostaining for LTx demonstrated positive reactions in the neutrophils that showed a progressive increase in intensity of staining with time in all groups exposed to 100% oxygen and in the group with high dose PQ, but the positive findings were weak in the group injected with low dose PQ only. We found the positive immunostaining reaction not only in neutrophils but also in alveolar macrophages. This indicates that LTx is produced by alveolar macrophages as well as by neutrophils depending on the treatment period under hyperoxic conditions, suggesting that LTx is an important chemical mediator in pulmonary diseases.

Animals↗
PubMed1995

Analysis of pedestrian injuries in traffic accidents (2)--Especially on leg injury.

A deep case study on 118 pedestrians struck to fronts of vehicles or vehicle derivatives was carried out. In this paper we investigated a leg injury which occurs the most frequently in a vehicle-pedestrian collision. The data obtained from the case study were compared with those of autopsied cases. Influence of impact speed and point, and of an accident pattern were considered. The leg injury showed higher AIS (Abbreviated Injury Scale) than that of the arm injury caused by direct impact against the front exterior of vehicles. The impact speed and ISS (Injury Severity Score) showed strong correlation, but the former and AIS did not show significant correlation. The higher impact speed and the run-over are likely to cause a bilateral leg fracture.

Abbreviated Injury Scale↗
PubMed1994

Production of monoclonal antibody reactive with leukotoxin and its immunohistochemical application.

A sensitive enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody (ALM-1) was developed for the determination of leukotoxin (9,10-epoxy-12- octadecenoic acid), which was reported to exist in human burned skin and neutrophils, and was regarded as a toxic and/or defensive substance in living beings. The leukotoxin was conjugated with bovine serum albumin (BSA) by means of the mixed anhydride technique as immunogen, and BALB/c mice were immunized over 6 months. The detection limit of leukotoxin was at least as low as 5 ng in this ELISA. This antibody had a strong specificity to leukotoxin and no cross-reactivity with the other analogs tested, and was usable for an immunohistochemical application. By using the antibody, leukotoxin was immunohistochemically observed not only in neutrophils, but also in alveolar macrophages in an oxygen-exposured rat lung.

Animals↗
PubMed1994

[An autopsy case of Smith-Lemli-Opitz syndrome].

A 17 month-old girl was found dead in her bed. The findings of a juditial autopsy revealed that she had a cleft palate, low-set and accessory ears, and syndactyly of right and left second and third toes and right third and fourth toes. Her birth size was small and subsequently she failed to thrive. Organ anomaly, such as atriaol septal defect, accessory spleens, and uterus bicornis bicollis were found. From these findings, this case was diagnosed as a Smith-Lemli-Opitz syndrome.

Abnormalities, Multiple↗
PubMed1994

Intercellular localization of leukotoxin (9:10-epoxy-12-octadecenoic acid) in lungs in rats by an immunoelectron microscopy.

In this paper intercellular localization of leukotoxin (9:10-epoxy-12-octadecenoic acid, LTx) in neutrophils and alveolar macrophages of rats exposed to the 100% oxygen was demonstrated by a pre-embedding method of an immunoelectron microscopy. The Sprague-Dawley rats were treated with the 100% oxygen for 72 hrs, and the lungs were stained with anti-LTx IgG (Fab) by an immunocytochemical method and examined by a transmission electron microscope. The positive reactions with anti-LTx IgG (Fab) was shown strongly in the rough-surfaced endoplasmic reticulum (rER) and cell membranes of the neutrophils and alveolar macrophages. This result indicates that LTx is produced in biomembrane-rich organelle of alveolar macrophages as well as neutrophils dependently on the treatment period under hyperoxia conditions, suggesting that LTx is closely related to biological reactions and is an important chemical mediator on pulmonary diseases.

Animals↗
PubMed1994

Identification and dynamics of paraquat in the bone marrow, thymus and spleen in rats using immunohistochemical techniques.

We reported the immunohistochemical identification of paraquat in the immune and hematopoietic systems such as bone marrow, spleen and thymus. Twelve paraquat-poisoned rats were sacrificed in 3 h, 12 h, 3 days, 7 days and 10 days after intravenous administration of paraquat. In the bone marrow, paraquat was localized in several types of blood cells (granulocyte, erythrocyte and megakaryocyte) and their precursors between 24 h and 7 days after the injection. In the thymus, paraquat was mainly localized in the medulla between 12 h and 7 days after the injection, whereas in the spleen, it was mainly localized in the red pulp between 12 h and 10 days after administration of paraquat.

Animals↗
PubMed1994

Experience with cloned mitochondrial DNA analysis to forensic practice.

The sequencing method of the D-loop region of cloned mitochondrial DNA (mtDNA) together with multilocus and single locus DNA probe patterns was applied to identification of the dismembered and putrefied remains of a pregnant woman. The multilocus DNA fingerprinting was useful to identify whether or not 4 dismembered remains were from the body of the same person, whereas the single locus DNA analysis was useful to decide that the suspect was the father of the fetus. On the other hand, the sequencing method of the D-loop region of cloned mtDNA after amplification by polymerase chain reaction (PCR) was particularly advantageous to highly degraded and contaminated DNA specimens.

Base Sequence↗
PubMed1994

Personal identification from human remains using morphological characteristics and DNA analysis.

This report describes personal identification of four parts of a dismembered human body on the basis of physical characteristics and DNA analysis. A 69-year-old woman suffering from depression went missing from her home in May 1992. Five days after her disappearance, a female torso was found in a river. In a two-week period thereafter, a left forearm, a female head and neck and a right forearm were found consecutively in the same river. Although the end of the cervical vertebra was anatomically identical to that of the torso, the two forearms did not match. However, DNA analyses with a single-locus DNA probe pYNH24, DO alpha typing and a multi-locus DNA probe "Myo", indicated that these four parts came from the same person. The missing woman had undergone lobectomy of the right pulmonary upper lobe, and had suffered from slight scoliosis of the thoracic vertebrae and a second lumbar vertebral compression fracture. These characteristics were also observed in the torso. In order to obtain more conclusive evidence, DNA fingerprinting using DNA extracted from the torso, the missing woman's brother and her daughter was performed using the DNA probes described above. The data obtained indicated that the remains were those of the missing woman.

Aged↗
PubMed1992

[Analysis of pedestrian injuries in traffic accidents: impact point, injury portion, and injury severity].

We conducted in-depth case studies of traffic accidents involving 118 pedestrians, who were struck by the fronts of bonnet-type cars. The data were reviewed in order to correlate injury severity with pedestrian age, and area of body contact, contact surface of vehicle or the local environment, and impact speed. It was found that head injuries caused by impacts against the top surface of car bonnets and leg injuries caused by front bumpers both showed high incidence rates. Both head and leg injuries caused by striking the vehicle were more severe than those caused by striking the road surface. In cases of impact between the head and the solid portion of the vehicle, such as the A-pillar, or in cases of secondary impact between the head and underhood solid structures such as shock tower, injuries tended to be more severe. The location of head impact varied according to the stature of the pedestrians.

Accidents, Traffic↗
PubMed1984

A method for monitoring ADP-induced thromboembolism in mice.

A method for monitoring ADP-induced thromboembolism in mice by means of the measurement of respiratory rate and depth was studied. The measurement were accurately carried out with a new method devised by us. In mice intravenously injected with 5-40 mg ADP/kg, it was found that the respiratory rate decreased transiently and dose-responsively, and that the platelet count also decreased transiently. On the other hand, no decrease in respiratory rate after administration of ADP was observed in neuraminidase-pretreated mice, in which the platelet count was significantly reduced. In the histological examination, platelet thrombi formed in the pulmonary vessels were observed 10 sec after administration of 10 and 40 mg/kg of ADP in mice which had not been treated with neuraminidase. The extent of thromboembolism at the dose of 40 mg/kg showed a tendency to be more marked than that at 10 mg/kg. Pretreatment with 300 mg dipyridamole/kg p.o. prevented the respiratory depression at 40 mg ADP/kg. However, with 10 mg dimorpholamine/kg i.v. or 30 mg warfarin/kg p.o., no preventive effect was observed. Therefore, it was concluded that it is possible to monitor ADP-induced thromboembolism in mice by means of the accurate measurement of the respiratory rate and depth.

Adenosine Diphosphate↗