Effect of toluene inhalation on astrocytes and neurotrophic factor in rat brain

Toluene, an abused substance in Japan, is a neurotoxic chemical that has been shown to have neurobehavioral and electrophysiological effects. In previous work, both acute and chronic effects of toluene on cells have been studied extensively. However, although glial cells are thought to play an important role in the survival of neurons in the brain, the effect of toluene on glial cell function has not yet been characterized. To elucidate this, the effect of toluene inhalation on astrocytes in rat brain was examined. Toluene exposure (1500 ppm for 4 h on 4-10 days) augmented glial fibrillary acidic protein (GFAP) immunoreactivity, particularly in the hippocampus and cerebellum. Quantitative analysis showed that toluene inhalation markedly enhanced GFAP expression in the hippocampus and cerebellum. In both regions, proliferating cell nuclear antigen (PCNA) showed no obvious changes, but glutamine synthetase (GS)-immunoreactive cells were markedly increased by toluene exposure. Thus, the elevation of GFAP expression was induced by astrocyte activation rather than by cell proliferation. If toluene exposure activates astrocytes, astrocytes may play a role in the neurophysiological changes observed in toluene intoxication. A neurotrophic factor, basic fibroblast growth factor (b-FGF) was observed immunohistochemically in the capillary vessel walls in the hippocampus and the cerebellum of toluene-intoxicated rats. Basic-FGF may have induced GFAP expression both in the hippocampus and the cerebellum. So, other neurotrophic factors may affect the difference of GFAP elevation between the hippocampus and the cerebellum. These differences may relate to neurobehavioral function of each brain part after toluene exposure.     

Sudden infant death syndrome: Histological studies on adrenal gland and kidney

Histological observations were made on the adrenal glands and kidneys in ten cases of sudden infant death syndrome (SIDS). The amount of fetal cortex was excessive in the adrenal glands and many glomeruli of fetal form were observed in the kidneys. These findings suggest that the adrenal glands and the kidneys in SIDS cases are more or less immature in development. The immature development in these organs, especially in the adrenal glands, was considered to play a role in the cardiac or respiratory mechanisms in SIDS.     

A single fatal penetrating chest wound caused by a dagger-shaped fragment of broken door glass

A 19-year-old woman ran against a glass door, and, breaking it, was struck in the left anterior chest by a single dagger-like fragment of broken door glass. This fragment deeply penetrated her chest and wounded the anterior wall of the left ventricle of her heart. She rapidly died from loss of blood. The majority of single fatal penetrating chest wounds seen at postmortem examinations are caused by firearms and bladed weapons. While penetrating chest wounds occasionally result from fragments of glass, most severe and fatal wounds from glass result from one's falling into or through plate glass and sustaining wounds of the head, face, abdomen, or extremities. A single fatal wound from a dagger-shaped piece of glass is distinctly uncommon. To prevent such an accident from occurring, safety glass must be used in front doors of public institutions.     

Studies on asphyxia: lipids in the alveoli of rats in hypoxic state

Biochemical characterization in alveolar lavage fluids of rats which had inhaled 5% oxygen, carbon dioxide and carbon monoxide was studied in comparison with control rats. The protein content, consisting mainly of serum albumin, markedly increased in the hypoxic states. The phospholipid content also increased one and a half to two times as much as in the control rats. The phospholipids which increased in the alveoli were mainly pulmonary surfactant phospholipids, i.e. phosphatidylcholine and phosphatidylglycerol. The phospholipid profiles did not appear to be affected by the leakage of plasma lipids. These findings indicate that pulmonary surfactant phospholipids accumulate in the alveoli of rats in the hypoxic states examined here.     

A frozen newborn infant: froth in the air-passage after thawing

We performed an autopsy on a frozen newborn infant who was found in a freezer at -18 degrees C. After thawing, froth emerged from the nostrils and was present in the trachea. Sometimes froth may be seen in the air-passage in cases of strangulation and drowning. In our case, however, there was neither proof of asphyxia due to strangulation nor drowning. The existence of the froth indicates that the infant was probably in a state of respiratory distress before death. Histologic findings of the lung showed that the infant did not suffer from respiratory disorders such as respiratory distress syndrome. Karyopyknosis and vacuolation of the keratinocytes, shrinkage of the hepatocytes, dilatation of the sinusoid, spaces between heart muscle fibers and deep staining of the nuclei and hemolysis were characteristic in our case. This case shows that froth persists in the internal air-passage for a long time as a result of freezing. Moreover, the froth in the air-passage, along with the findings of the lungs, demonstrates that the newborn infant was born alive.     

Paraquat myopathy: report on two suicide cases.

We describe two suicide cases in which old paraquat was ingested. In conjunction with lung involvement a pronounced degeneration was observed in skeletal muscle of one who died on the 14th day after the ingestion. The following sarcoplasmic or endoplasmic reticulum Ca2+ ATPase (SERCA) monoclonal antibodies were used for skeletal muscle fiber typing by an immunohistochemical method: NCL-SERCA1, reactive with type 2 fiber (fast-twitch), and NCL-SERCA2, reactive with type 1 fiber (slow-twitch). The examination revealed that the remarkably degenerated fibers belonged to type 1 muscle fibers. This case showed an abrupt increase of plasma CK levels (1796 mU/ml) on the fifth day after the ingestion. The authors presume that the damage to the skeletal muscle had occurred in this period. The degeneration of the muscle seemed to be attributable to the long retention of paraquat in the tissue because these findings were not observed in the other case who died on the fifth day. Paraquat-induced myopathy may develop in prolonged paraquat poisoning. The examination of CK levels in plasma will be useful for diagnosis of damage of skeletal muscle.     

Determination of Both Fetus’ and Mother's Blood Type from an Autopsy Case Immersed in Formalin for Over 50 Years

A female fetus which had been immersed in formalin for more than 50 years was found in Japan. Because no liquid blood could be obtained, we tried to use immunohistochemistry (IHC) methods to tissue samples obtained at autopsy to identify both the fetal and mother's blood type. We detected B antigens on endothelial cells in paraffin sections of the fetal organs. Furthermore, we observed both anti‐A‐ and anti‐B‐positive red blood cells in the intervillous space, which is indicative of the mother's blood type. To our knowledge, this is the first case report on determining the blood type of both the fetus and the mother from tissue immersed in formalin for such a long time. The results suggest that IHC is valuable for the determination of ABO blood type in circumstances of long postmortem duration and unfavorable storage conditions.     

Medicolegal aspects of infanticide in Hokkaido District, Japan

Since 1978, a total of 55 infanticides were investigated by our department (16.9% of the total number of medicolegal autopsies). This article describes the infanticides in the Hokkaido district of northern Japan. The characteristic finding for the cause of death was drowning in the toilet. This mode of killing seems to be chosen because of the style of toilet in the district, which includes a collecting tank for feces and urine under the commode.     

Asians for Australia's identity

Australia is now pursuing the task of discovering and creating its own identity, says Keiko Morita, lecturer at the Institute for International Studies, University of Technology, Sydney. Following remarks made by Pauline Hanson during the 1996 federal election, the issue of Asian immigration has been the subject of significant public debate in Australia. Morita argues that the uproar provoked by Hanson's blatant exploitation of racist hostilities has made it pertinent to raise the question of how Australian feelings toward Asian immigrants have changed over the last thirty years.     

Studies on asphyxia: on the changes of the alveolar walls of rats in the hypoxic state. II. The hypoxic state produced by carbon dioxide and methane gases

Experimental studies were presented here concerning death by asphyxia due to the inhalation of carbon dioxide and methane gases. The morphological changes were almost the same as those demonstrated in our previous report. The authors concluded that the morphological changes in the lung tissue were not attributable to the chemical specificity of gases used in the experiment but to the decrease of oxygen.