Induction of nitric oxide synthase by traumatic brain injury.

We investigated the dynamic induction/expression of inducible nitric oxide synthase (iNOS) using human brains made available through death by traumatic brain injury (TBI). Astrocytes, microglia, and neutrophils were identified in tissue using immunohistochemical staining with antibodies against glial fibrillary acidic protein (GFAP), MHC class II antigen, and neutrophil elastase, respectively. The localization of iNOS protein in each of these cell types was evaluated using immunohistochemistry. Within 2 days of injury, iNOS immunoreactivity was not detected. However, after 2 days, immunoreactivity was detected in the traumatized brain. The iNOS immunoreactivity was localized on neutrophils and microglia/macrophages in the areas around the tissue necrosis in the traumatized cortical hemisphere, in the deep part of the cortex and the dentate gyri of the hippocampi adjacent to the hemorrhage, and within the cytoplasm of vascular smooth muscle cell of a small artery or arteriole surrounding the injured region. This reactivity was absent after 8 days post-injury.These observations confirmed the prolonged induction of iNOS within various cells in the injured brain. These responses suggest that iNOS plays a crucial role in cerebrovascular damage and/or secondary brain damage subsequent to traumatic brain injury. Furthermore, the dense nitric oxide (NO) generated by iNOS may play a role in neuronal cell death after injury.

The expression of excitatory amino acid transporter 2 (EAAT2) in forensic autopsy cases.

Glutamate is the major excitatory neurotransmitter and the greater part of this amino acid is removed from the synaptic cleft by excitatory amino acid transporter 2 (EAAT2) located on perisynaptic astrocytes. Recently, it was reported that the EAAT2 protein content changed in rats following forebrain ischemia and administration of methamphetamine. We planned to demonstrate the immunohistochemical distribution of EAAT2 in the human brain and discuss the significance of its pathophysiological roles. Thirty-two cases were used from forensic autopsies. The tissues were sampled from the cerebral cortex, striatum and hippocampus. The distribution of EAAT2 was difficult to identify in cases of electrical fatalities. However, continuous and extensive staining of EAAT2 was observed in cases of death from hypothermia. In almost all asphyxia death, we were able to observe a weak stain of EAAT2. In case of solvent abuse, EAAT2 staining was continuous and extensive as in the cases of hypothermia, and patchy negative zones were mixed. This study clearly showed the differences in EAAT2 localization according to the cause of death. These findings suggested that the differences in EAAT2 staining depended on the cause and course (pathophysiological conditions) of death.

An autopsy case of neuroleptic malignant syndrome (NMS) and its immunohistochemical findings of muscle-associated proteins and mitochondria.

Neuroleptic malignant syndrome (NMS) is a rare but potentially fatal disorder. In forensic cases, post-mortem diagnosis of NMS is sometimes difficult if ante-mortem information, such as neuroleptic ingestion or signs and symptoms, cannot be obtained. A 39-year-old Japanese male on a neuroleptic treatment regimen suddenly became agitated and died. Autopsy revealed muscle rigidity and hyperthermia. Post-mortem examination of blood revealed elevation of creatine phosphokinase-MM (CK-MM) and lactate dehydrogenase-4 and dehydrogenase-5 (LDH-4 and LDH-5). In renal glomeruli and tubules, myoglobin was stained immunohistochemically. From these findings, the cause of death was considered to be NMS. To support the diagnosis of NMS, both skeletal and cardiac muscles were stained with actin, myoglobin, desmin and mitochondria antibodies immunohistochemically. Actin, myoglobin, desmin, and mitochondria had been lost from skeletal, but not from the cardiac muscle, which suggested that only the skeletal muscle was damaged. Moreover, because mitochondria had disappeared only from the skeletal muscle, it was considered that skeletal muscle degeneration was caused by mitochondrial damage. Therefore, it is suggested that immunostaining of skeletal muscle by antibodies for muscle-associated proteins and mitochondria is useful to corroborate a diagnosis of NMS.

[Application of immunohistochemistry for forensic pathological diagnosis: finding of human brain in forensic autopsy].

We researched the application of immunohistochemistry for the purpose of establishing forensic pathological diagnoses. In the present study, we examined the induction and expression of heat shock protein (HSP), oxygen regulated protein (ORP), inducible nitric oxide synthase (iNOS), excitatory amino acid transporter 2 (EAAT2) and apolipoprotein E (apo E) in the human brain using forensic autopsy cases as our subjects. Hypoxic/ischemic brain damage. In cases of longer survival and with a history of hypoxic attacks, the proteins HSP and ORP were found in the parieto-occipital lobe and hippocampus. And we are able to observe a weak stain for EAAT2 in almost all asphyxia deaths. Traumatic brain injury (TBI). In traumatic brain injury (TBI), the prolonged induction of iNOS was demonstrated in the neutrophils, microglia/macrophage, and vascular smooth muscle cells in the traumatized brain. Apo E was identified with neurons in the traumatized cortical hemisphere from only a two-hour survival case to long survival cases. To the contrary, there was no positive apo E staining in the contralateral cortical hemisphere at all. In one one-hour survival case, a weak stain for EAAT2 was observed, but intensive expression of EAAT2 was observed from brief to one-day survival cases. Sudden infant death (SID). Numerous ferritin-positive cells were observed in the brain in the cases of pneumonia or myocarditis that we examined. To the contrary, the numbers of ferritin-positive cells were obviously decreased in the cases of sudden infant death syndrome (SIDS). The transferrin-positive cells were in an inverse proportion to the ferritin positive cells in each SIDS case. Also, numerous ORP-150 positive cells were observed in the brain in cases of pneumonia and the SIDS group. In forensic practice, immunohistochemical investigation of these proteins can be a great value for diagnosing not only the cause of death but also the pathophysiological changes and the victims past history.

[A proposal of essentials for forensic pathological diagnosis of sudden infant death syndrome (SIDS)].

There are many sudden unexpected infant death cases which are easily diagnosed as sudden infant death syndrome (SIDS) both with or without autopsy in Japan. A SIDS diagnosis may provide a cover for accidental or criminal death. SIDS should not be a convenient diagnostic box that shelters the cases of unexpected infant death which lack the necessary antemortem information to make the correct diagnosis. The authors consider that SIDS should be diagnosed according to the direction of the international definition of SIDS, and propose the following essentials for a forensic pathological diagnosis. 1) A thorough autopsy should be performed based on precise autopsy protocol, including not only histological observation, but also, if necessary, toxicological, bacteriological, viral and/or biochemical examinations. 2) The forensic pathologist should be provided with pertinent information regarding antemortem health status, past clinical history, social circumstances, death scene investigation, etc. In order to collect more precise information, the authors recommend using a questionnaire such as the example in this report to record information from the deceased's guardians. 3) Suspicion of accidental death or infanticide should be completely ruled out. SIDS should be diagnosed only after these three essentials have been satisfied. When there is even a slight suspicion of accidental death or infanticide, or when the forensic pathologist can not obtain pertinent information about the deceased, the causes and classification of the death should be diagnosed as unspecified or undetermined. That is, the causes and classification of the death are undetermined as to whether it is a natural or unnatural death. Furthermore, several warning flags indicating a possible SIDS diagnosis were proposed: a case found dead in a supine position, the existence of a foreign body in the respiratory tract or mild infectious findings. The authors also emphasize the physician's responsibility to report a case found dead or dying of unnatural or clinically unexplained causes to the police. This is the crucial first step in getting an accurate diagnosis of SIDS.

HSP70 and c-Fos expression of brain stem hypoglossal nucleus in drowning.

The brain stem hypoglossal nucleus (HN) is the center of nerves innervating the upper respiratory tract and is related to control of mastication, deglutition, speech and respiration. To elucidate the relationship between asphyxia and the HN, we investigated the change of hypoglossal neurons in cases of hanging, strangulation, smothering, choking, drowning and respiratory failure. Using immunohistochemical techniques, we observed the brain stem HN with antibodies against microtubule-associated protein 2 (MAP2), muscarinic acetylcholine receptor (mAChR), c-fos gene product (c-Fos) and 72 kD heat-shock protein (HSP70). MAP2, a cytoskeletal protein of the neuron, is a marker of neuronal damage. Muscarinic AChR was used as a marker of neuronal membrane and ACh signaling. We employed both HSP70 and c-Fos as markers of stress- or damage-related events. We measured the percentage of immunopositive neurons in total neurons of HN. Drowning produced higher expression of HSP70 and c-Fos than other causes of asphyxia, suggesting that drowning induces more severe damage in HN neurons. Furthermore, it was suspected that neuronal changes in drowning might relate to functions of the HN. These observations indicate that immunohistochemical examination of the brain stem HN could provide useful information for determining the cause of asphyxia.

One autopsy case of an elderly traffic accident victim with tetralogy of Fallot.

The case of a 61-year-old male traffic accident victim with Tetralogy of Fallot (TOF) is reported. The autopsy revealed massive hemorrhages in the subcutaneous tissue, muscle, and subarachnoidal space. Furthermore, multiple fractures of ribs, sternum and thoracic vertebrae were observed. Histopathological examination revealed changes characteristic of trauma, such as acute lung congestion, acute renal cortical necrosis, and embolization in the lungs and kidney. These autopsy and histological observations indicated that traumatic shock was cause of his death. Moreover, histologically, we observed changes due to his congenital heart disease, such as right ventricular hypertrophy, heart failure cells in the lungs, sclerosis of the liver, and hyaline degeneration in the kidney. Furthermore, ischemic changes, shrinkage or loss of neurons, were seen in hippocampus, and swelling of astrocytes in both cortex and hippocampus were also observed. These observations lead us to speculate that a hypoxic episode may have caused his accidental death while driving.

Immunohistochemical diagnosis and significance of forensic neuropathological changes.

Immunohistochemistry is very useful when investigating the cause of death. Ischemic cell changes in the hippocampal neurons were not obvious in the brains damaged by hypoxic injury. However, it is suggested that even a moderate hypoxia, which may affect the neuronal proteins and metabolism, induced astrocytosis in the CA3 and CA4 regions, and that in patients with a history of hypoxic attacks neuronal damage may be severe even several hours after ischemic injury. Furthermore, hsp70 expression was found in the CA2, CA3 and CA4 regions of long-term survivors after severe hypoxic/ischemic injury. In forensic practice, detailed information about the duration and extent of a hypoxic/ischemic injury is often unavailable, so that immunohistochemical detection of hsp70 and glial cell staining can be of great value in diagnosing not only the hypoxic/ischemic injury during the process of death but also the victim's past history of hypoxic attacks. In diffuse axonal injury, degeneration of axon and myelin, such as swelling and waving, were observed in survivors of more than 8 hours. Retraction balls appeared in survivors of more than 1 days. In longer term survivors, such as 3 or 5 months, breakdown of myelin and fat-granule cells were observed. In addition, retraction balls were also found. Immunohistochemical staining of 200 kD neurofilament was a very useful method to examine axonal changes, because antisera is specific for degenerative neurofilaments. In our study, all cases which had pathological findings of diffuse axonal injury (DAI) were associated with focal head injuries. From the immunohistochemical staining of neurons in the hippocampus, it was suggested that neurons in the hippocampus were injured by diffuse brain damage. Furthermore, repairing and protective mechanisms occurred especially from CA2 to CA4. It was considered that neuronal damage in diffuse brain injury was elucidated not only morphologically but also functionally. Therefore, in cases of suspected diffuse brain damage, it is recommended to examine the neuronal changes in addition to observing the findings of diffuse axonal injury. Immunohistochemical staining of the carotid body is potentially very useful for necropsy diagnosis, since it provides a method to detect evidence of mechanical asphyxia in suspected cases of manual and/or ligature strangulation.

[Immunohistochemical studies on neuronal changes in brain stem nucleus of forensic autopsied cases. I. Various cases of asphyxia and respiratory disorder].

Several nuclei in brain stem are well known to play an important role in supporting human life. However, the connection between neural changes of brain stem and the cause of death is not yet fully understood. To investigate the correlation of brain stem damage with various cause of respiratory disorders, neural changes of the arcuate nucleus (ARC), the hypoglossal nucleus (HN) and the inferior olivary nucleus (IO) were examined using immunohistochemical technique. Based on the cause of death, the forensic autopsy cases were divided into 5 groups as follows. Group I: hanging, ligature strangulation and manual strangulation, Group II: smothering and choking, Group III: drowning, Group IV: respiratory failure, control group: heat stroke and sun stroke. Brain was fixed with phosphate-buffer formalin, and the brain stem was horizontally dissected at the level of apex, then embedded in paraffin. The sections were stained with the antibodies against microtubule-associated protein 2 (MAP2), muscalinic acetylcholine receptor (mAChR), c-fos gene product (c-Fos) and 72 kD heat-shock protein (HSP70). Three nuclei showed no obvious morphological changes in all examined groups. However, in case of asphyxia (Group I to III), neurons in HN were positively stained with both HSP70 and c-Fos antibodies. This may indicate that the occlusion of upper airway results in the neuronal damage of HN without their morphological changes. Positive staining of HSP70 and c-Fos in IO was more frequently observed in Group III than other 4 groups. Since IO is involved in maintaining body balance which is often disturbed by drowning, it seems possible that neuronal damage in IO observed in drowning may be related to the disturbance of body balance. These observations indicate that immunohistochemical study on the damage to neurons in brain stem nuclei can provide useful information for determining the cause of death.

[Immunohistochemical studies on neuronal changes in brain stem nucleus of forensic autopsied cases. II. Sudden infant death syndrome].

Several nuclei in brain stem are well known to play an important role in supporting human life. However, the connection between neural changes of brain stem and the cause of death is not yet fully understood. Previously, in sudden infant death syndrome (SIDS) it has been suggested that impaired cardioventilatory control might contribute to cause of death. So, to investigate the brain stem damage in SIDS, neural changes of the arcuate nucleus (ARC), the hypoglossal nucleus (HN) and the inferior olivary nucleus (IO) was examined using immunohistochemical technique. Brain was fixed with phosphate-buffer formalin, and the brain stem was horizontally dissected at the level of apex, then embedded in paraffin. The sections were stained with the antibodies against microtubule-associated protein 2 (MAP2), muscalinic acetylcholine receptor (mAChR), c-fos gene product (c-Fos) and 72 kD heat-shock protein (HSP70). Morphological changes of neurons in three nuclei were not evident. Moreover, because MAP2 degeneration and expression of HSP70 and c-Fos were not observed, neuronal damage in those nuclei was not suspected. However, although there was no abnormality of mAChR immunostaining in HN and IO, the rate of mAChR-immunopositive neurons in ARC was less than that in control. These observations indicate that immunohistochemical study on the neuronal changes in ARC can provide useful information for diagnosing SIDS.

Isolated adrenocorticotropic hormone deficiency: an autopsy case of adrenal crisis. A case report.

We present a case of fatal adrenal crisis due to isolated adrenocorticotropic hormone (ACTH) deficiency. Autopsy revealed each adrenal gland weighed 0.9 g and the adrenal cortexes were very thin and atrophic. Additionally, cortisol could not be observed in the adrenal cortex by immunohistochemical staining. Furthermore, urine cortisol and 17-OHCS concentration had decreased to a very low level, 20 mg/L and 0.8 mg/L respectively. The anterior pituitary gland was atrophic, and showed fibrosis and lymphocytosis was suspected. Immunohistochemically growth hormone (GH)-stained pituitary gland cells were observed, but there were no cells stained with anti-ACTH antibody. From the history and pathological findings, no other deficiencies of pituitary hormones were evident. Therefore, isolated ACTH deficiency was suspected. Furthermore, as the thyroid gland showed lymphocytic thyroiditis, is was considered that isolated ACTH deficiency was associated with an autoimmune cause. Generally, as patients of chronic adrenocortical insufficiency are exposed to stress and, therefore, have an increased requirement for glucocorticoids, the blood pressure falls, leading to hypovolemic shock called " an adrenal crisis." Without treatment, patients die in crisis within several hours. In our case, the deceased had drunk alcohol without sleep for 2 days. We believe that the stress of drinking and sleeplessness induced adrenal crisis and caused his death.

[An autopsy case of the Reye's syndrome].

A case of sudden unexpected natural death in a 6-year-old girl was reported. She was found in dead with vomiting on her bed in the morning on 24. December. Autopsy did not reveal any injuries and abnormalities on her appearance. Small amount of light yellowish mucus in her nose, trachea and bronchus was found. Brain was slightly edematous (1395 g in weight). Liver was 750 g in weight and focal yellowish lesions were observed on its cut surfaces. Microscopically fatty degeneration (granulous fatty deposits) was observed in hepatocytes. Immunohistochemical staining of mitochondria in heart showed no staining microscopically, and degeneration and breakdown of mitochondria were found electromicroscopically. From the results of autopsy and histopathological findings, her cause of death was diagnosed as the Reye's syndrome.

[An autopsy case of traumatic subdural hematoma from arterio-venous malformation with diffuse axonal injury].

Diffuse axonal injury (DAI) is defined as widespread damage to axons in the white matter of the brain without focal injury such as contusion and acute subdural hematoma. A case of traumatic subdural hematoma from arterio-venous malformation accompanied by DAI is reported. A 58-year-old man was assaulted, and immediately lost consciousness, and remained unconscious during about 44 hours until his death. The autopsy revealed acute subdural hematoma (about 160 g) on left temporal lobe and left cingular, uncal and cerebellar tonsillar herniation, and tear and hemorrhage of the corpus callosum. Under this subdural hematoma, gray-whitish vascular lesion with subarachnoid hemorrhage was found. Histologically, this lesion was diagnosed as the arterio-venous malformation. Neuropathological examination of the corpus callosum, dorsolateral part of midbrain and superior cerebellar peduncle revealed DAI findings, such as swelling and ballooning of the myelin fibers, swelling and waving of axons, and retraction balls. Axon degenerations were also observed immunohistochemically by anti-200 kD neurofilament antibody. From the results, his unconsciousness from the moment of impact might be occurred from not only subdural hematoma but also DAI.

[An autopsy case of Sjögren syndrome with organized and fresh subdural hemorrhage (hematoma)].

An autopsy case of Sjögren syndrome with organized and fresh subdural hemorrhages (hematoma) is reported. A 49-year-old woman who had been suffering from Sjögren syndrome had gradually lost her consciousness and was taken to the hospital where she died several hours later. Subsequently a doctor found the subdural hematoma of unknown origin on her Brain CT. At autopsy, her skin was dry and all of her teeth were missing. There were sporadic cutaneous purpura and subcutaneous hemorrhages in her trunk and limbs. The histopathological examination revealed that the submandibular gland had no normal acini, and was replaced by fibrous and adipose tissues with numerous lymphocytes. There were signs of fibrosis with inflammation in her liver, kidneys and lungs. The thyroid gland showed thyroiditis. Serological findings showed a significant high level of antinuclear antibody, positive RA factor and high gamma-globulinemia. The autopsy revealed that her cause of death was acute subdural hematoma and uncal herniation. There were no external injuries on her head or face. It is suggested that her acute subdural hematoma according to the hemorrhagic tendency, affected by her Sjögren syndrome.

Immunohistological investigations of autopsied carotid bodies and their application to diagnosing strangulation.

Using immunohistochemical staining, the histological changes and the presence of neuropeptides (enkephalin and VIP) in the carotid body have been investigated in medico-legal autopsy cases, especially asphyxia cases. Only in cases of manual and/or ligature strangulation cases that sustained a force near the carotid body, were the chief cells mainly lightly stained, indicating that they had been "active" cells. Furthermore, these cells and their nuclei were enlarged in comparison to the chief carotid body cells in other autopsy groups. It was thus felt that these changes had resulted from the force that had directly affected the carotid body. Based on these findings, it was concluded that immunohistochemical investigation of the carotid body offers a useful possibility for diagnosing manual asphyxia, especially in autopsy cases involving strangulation.

[Paternity test by DNA fingerprinting in a sexual assault].

We have applied the method of DNA fingerprinting to resolve a paternity case. DNA samples were extracted from the blood of mother, child (4 months old fetus) and alleged father, digested with the restriction endonuclease Hinf I and Hae III, size separated by agarose gel electrophoresis, and hybridized with the multi-locus minisatellite probe B.E.S.T.-MZ1.3 digoxigenin. DNA fingerprinting patterns in the child and alleged father indicated possibly paternity. Following extraction of DNA from cord blood (infant of 26 to 39 week's gestation), the quantity of DNA isolated was determined on a spectrophotometer at 260 nm and its integrity by electrophoresis in agarose gels. We found that high-molecular-weight DNA could be recovered in large quantities from cord blood as well as from adult blood.

Hereditary recombined three-allele variant of the Gc system.

A three-allele variant with Gc 2, Gc 1F and Gc 1A2 alleles was detected in both a baby and his mother during paternity testing by isoelectric focusing. His father had a normal Gc phenotype, Gc 2-1F. Further examination of his mother's relatives revealed that his grandfather also had the same three-allele variant, while his grandmother and his aunt had normal Gc 2-1F and Gc 2-2. From these results, it was considered that the Gc 1F and Gc 1A2 alleles were on the same single chromosome. It was suggested that recombination had occurred between two chromosomes that had the Gc 1F and Gc 1A2 allele, respectively, forming the variant allele Gc 1F1A2 on a single chromosome.

An asthmatic death while under Chinese acupuncture and moxibustion treatment.

A 29-year-old Japanese man with bronchial asthma died while undergoing Chinese acupuncture and moxibustion treatment. The autopsy findings of the lungs were compatible with a diagnosis of severe asthma. Further, on immunohistochemical examination, hypoxic brain damage and an unusual distribution of pulmonary surfactant were found. In contrast, only minor hemorrhages in the right semispinal muscle and round-shaped bruises were seen as a result of Chinese acupuncture and moxibustion treatment. Thus, it was concluded that the man had died from a severe asthmatic attack.

[Forensic autopsy--anatomical diagnosis of asphyxial death].

In hospital cases, since a clinical history is usually present and the cause of death suspected, the chief duty of the pathologist is to describe and study the pathologic conditions revealed by his dissection. In medicolegal cases, the forensic pathologist must determine the cause of death and the circumstances of death, without any clinical history or clue to guide him except the lesion of trauma or disease which he discovers post mortem. The recognition of asphyxia as a cause of death at autopsy is occasionally difficult and requires considerable care, skill and understanding based on experience of the forensic pathologist. When a mechanical asphyxial death is suspected, the following method is a convenient routine procedure in our laboratory. 1. External Examination A systematic and careful examination of the external feature is made. 2. Internal Examination A "U" shaped incision is the most satisfactory method to inspect the internal tissues of neck in situ. 3. Laboratory Investigation The tissue examined routinely under the microscope are cervical lymph node, tongue, carotid body, lung, cortex of brain and skin. The heart's blood is collected to examine the fibrinolytic factors and thyroid hormones.

Demonstration of hemoglobin in the kidney of battered children.

We examined specimens of renal tissue taken from 40 cadavers of children (18 battered and 22 non-battered children) by an immuno-peroxidase technique using anti-human hemoglobin (Hb) or anti-human myoglobin (Mb) antiserum. Hb was detected in the proximal tubular cells of the kidney of six battered children who had sustained severe or moderate external injuries, whereas Mb was not found. In contrast, Mb was detected and Hb was not found in the renal tubules of one child who had died from a traffic accident. In other cases including 13 cases of children who died from a sudden bout of physical violence or some other impulsive act and 4 cases of children who had died from malnutrition, neither Hb nor Mb was found in the kidney. Our findings appear to indicate that large quantities of Hb were released from the multiple lesions of the battered children, entered the circulation and were deposited in the kidneys. It thus seems that the immunohistochemical detection of Hb in the kidney may be useful for evidencing the extensive antemortem bruises which are often found in battered children.