Role of hippocampal oxidative stress in memory deficits induced by sleep deprivation in mice.

Numerous animal and clinical studies have described memory deficits following sleep deprivation. There is also evidence that the absence of sleep increases brain oxidative stress. The present study investigates the role of hippocampal oxidative stress in memory deficits induced by sleep deprivation in mice. Mice were sleep deprived for 72 h by the multiple platform method-groups of 4-6 animals were placed in water tanks, containing 12 platforms (3 cm in diameter) surrounded by water up to 1 cm beneath the surface. Mice kept in their home cage or placed onto larger platforms were used as control groups. The results showed that hippocampal oxidized/reduced glutathione ratio as well as lipid peroxidation of sleep-deprived mice was significantly increased compared to control groups. The same procedure of sleep deprivation led to a passive avoidance retention deficit. Both passive avoidance retention deficit and increased hippocampal lipid peroxidation were prevented by repeated treatment (15 consecutive days, i.p.) with the antioxidant agents melatonin (5 mg/kg), N-tert-butyl-alpha-phenylnitrone (200 mg/kg) or vitamin E (40 mg/kg). The results indicate an important role of hippocampal oxidative stress in passive avoidance memory deficits induced by sleep deprivation in mice.

Rheologic changes in venous blood during prolonged sitting.

We examined blood rheologic changes, mainly blood viscosity, during long-term quiet sitting. Samples of blood were obtained from the arm and foot veins of the healthy adult male volunteers before and after 2 h of quiet sitting. Blood viscosity, was immediately determined with an oscillation viscometer, and blood count and blood chemistry were analyzed. We found that the viscosity in blood from a foot vein but not from an arm vein increased significantly after 2 h of sitting. Our results show that 2 h of quiet sitting can increase thrombotic tendency locally in the leg but not systemically and suggests the importance of measuring focal venous blood viscosity.

Changes in blood viscosity by heparin and argatroban.

Anticoagulants are effective for preventing both venous and arterial thrombosis. Although antithrombotic agents have been reported to reduce thrombin formation, to our knowledge, the relation between blood viscosity (BV) and antithrombotic agents has not been examined. We examined the effects on whole BV of various dosages of the antithrombotic agents-heparin sodium and argatroban. Thirty microliters of either drug was added to 3-ml samples of blood obtained from healthy male volunteers. Whole BV was then immediately examined with an oscillation-type viscometer. When either agent was added, BV decreased and coagulation time increased dose dependently. BV was 4.5+/-0.3 mPa.s in untreated blood but decreased in a dose-dependent manner to a minimum of 2.5+/-0.3 mPa.s with heparin sodium and decreased dose dependently in a sigmoid manner with argatroban. Because thrombin generation is inhibited in all antithrombotic therapies, this inhibition might be reflected by changes in BV. Our results suggest that BV in accordance with blood coagulability are indexes of thrombotic tendency and that decreasing BV prevents life-threatening thromboembolic conditions.

Autopsy case of duodenal obstruction from impacted mushroom.

We report an autopsy case of duodenal bulb obstruction caused by a shiitake mushroom. A 74-year-old woman with depression was admitted to the hospital after suffering nausea and abdominal fullness for 3 days. Because the physical findings and laboratory data on admission revealed marked dehydration, lactated Ringer's solution was administered. Twelve hours later, the patient suddenly died. Autopsy showed an enlarged stomach filled with 850 ml of partially digested food. In the anal side of the pylorus, a 9-cm-diameter shiitake mushroom had become impacted, causing complete obstruction. We conclude that the patient suffered from duodenal bulb obstruction caused by the impacted mushroom and subsequently died of ileus. This case illustrates a rare cause of duodenal obstruction and emphasizes that ingested food can cause obstructive ileus and death.

Arsenic accumulation in organs of the fresh water fish Tribolodon hakonensis.

The fish Tribolodon hakonensis lives in good health in Lake Usoriko, which has been acidified and naturally contaminated with arsenic by volcanic activities. We have determined the contents of various metals in various fish organs of T. hakonensis, collected at Lake Usoriko. We found that a large amount of arsenic was accumulated in the eye, especially in the choroid-retina part. The arsenic concentrations in the liver and kidneys were about 0.4 microgram/g (wet), whereas the muscle contained less arsenic. The arsenic accumulation in the skin was also observed, especially in the epaxial part. Zinc and arsenic contents in various fish organs correlated well.

Immunohistochemical study of neuron-specific enolase in human brains from forensic autopsies.

Immunohistochemistry using anti-human neuron-specific enolase (NSE) mouse monoclonal antibody was performed in human brains from autopsy cases, which enabled us to assess the neuronal damage besides hematoxylin and eosin or Klüver-Barrera stain. Neurons in cerebral neocortex which showed necrotic changes such as prominent cytoplasmic vacuolization or cellular shrinkage with nuclear pyknosis showed a tendency to be less stained by anti-NSE antibody. Anti-NSE immunostaining was statistically significantly less in the neocortex from CO intoxication than from other causes of death, although morphological necrotic changes were less observed in CO intoxication. Hippocampal CA1 neurons clearly lost NSE immunoreactivity with the progression of necrotic changes. Neurons in CA2 were statistically significantly better stained by anti-NSE antibody than in CA1, 3, and 4. Cerebellar Purkinje cells were poorly stained by anti-NSE antibody, whereas neurons in cerebellar dentate nucleus and inferior olive in medulla oblongata were better stained. Anti-NSE immunostaining was lost in the injured areas of the cerebral neocortex while neurons in the intact areas were better stained in brain injury. These results indicate that anti-NSE immunostaining of neurons could reflect vital reaction and could be useful in evaluating neuronal damage in the hippocampal CA1 region or brain injury.

Immunohistochemistry of neuron-specific enolase in neurons of the medulla oblongata from human autopsies.

Neuron-specific enolase (NSE) is a glycolytic enzyme specifically expressed in neurons. NSE has been used as a marker for neuronal damage in brain injury. We studied the immunohistochemical localization of this enzyme in the medulla oblongata obtained from human forensic autopsy specimens. Neurons in the dorsal motor nucleus of vagal nerve expressed statistically significantly less NSE immunoreactivity in the cytoplasm than in the hypoglossal nucleus (XII), solitary nucleus, spinal trigeminal nucleus, and lateral cuneate nucleus. Cases of carbon monoxide intoxication by burning showed a higher incidence of NSE immunoreactivity in the cell nucleus of the XII than other cases, while there was no statistically significant correlation between NSE immunoreactivity in the cell nucleus and the Nissl amount. This indicates that the accumulation of NSE immunoreactivity in the cell nucleus might be a vital reaction rather than a postmortem artifact.

A case of strangulation by a vehicle seat belt.

A healthy 23-year-old man wearing a three-point seat belt suffered from a roll-over traffic accident. When the man was found, the fastened seat belt had loosened and the diagonal belt was tightened against the neck. Autopsy findings revealed ligature marks on the surface of the neck, hemorrhages in the muscles of the neck, petechial hemorrhages in palpebral conjunctivae and viscera, dark red liquid blood in the heart cavities and visceral congestion. We concluded that the man died of strangulation by the seat belt. In this case, the loose belt allowed the body to move and subsequently the diagonal belt applied external pressure to the neck while the car was rolling over. Although there have been several reports of neck injuries due to diagonal belts, this is the first report of strangulation by a properly used three-point belt in a roll-over vehicle accident.

Injury severity in motor vehicle occupants.

We performed a retrospective analysis of injury severity and the effect of seat belt use with findings from forensic autopsies of 50 persons who had died in motor vehicle accidents. From autopsy findings and accident reports, the abbreviated injury scale (AIS) and the injury severity score (ISS) were calculated and analyzed epidemiologically. Among unrestrained occupants, drivers usually sustained more severe chest and abdominal injuries. Furthermore, three-point seat belts significantly decreased the severity of drivers' chest and abdominal injuries. Our results may be useful for forensic pathologists and clinicians and for mechanical engineers who investigate new safety devices for vehicle occupants.

Immunohistochemical localization of heat shock protein 70 in the human medulla oblongata in forensic autopsies.

Heat shock protein 70 (hsp70) can be induced under various stresses in experimental animals. We investigated hsp70 immunoreactivity in the human medulla oblongata in forensic autopsies. Hsp70 immunoreactivity was observed in the cytoplasm of some neurons in the hypoglossal nucleus (XII), the dorsal motor nucleus of the vagal nerve (X), the lateral cuneate nucleus (Cun), and the inferior olive (Oli). Neurons with positive hsp70 immunoreactivity were statistically significantly fewer in the Oli than in the XII, X, and Cun. There was no statistically significant correlation between the AMI (the antemortem interval between the onset of injury and death) or PMI (the postmortem interval between death and autopsy), and the percentage of positive cytoplasmic hsp70 immunoreactivity in any of the nuclei studied. Age had a statistically significant negative correlation with the percentage of positive hsp70 immunoreactivity in the Oli. The percentages of positive hsp70 immunoreactivity in the XII and Cun were statistically significantly lower in burn cases than in other cases. Therefore, the induction of hsp70 immunoreactivity in the medulla oblongata may not reflect the duration of stress in the AMI, but may reflect the regional (nuclei) and conditional (burns) differences in autopsy specimens.

IgG immunohistochemistry for the assessment of brain injuries in forensic autopsies.

Immunohistochemical staining of IgG in the sections of injured brain areas was performed in forensic autopsies. IgG immunoreactivity was present mainly in glial cells surrounding hemorrhagic areas, which may be a useful tool to detect and evaluate injured areas of the brain in forensic autopsies.

Estimation of normal heart weight in Japanese subjects: development of a simplified normal heart weight scale.

To estimate cardiac workload from total heart weight (HW) in persons who have died suddenly, standards of normal HW must be established. We present standards of normal HW for Japanese subjects and propose a simplified scale for calculating normal HW from body height (BH) and body weight (BW). A total of 830 persons (506 male and 324 female) who had died suddenly of unnatural causes were selected for analysis from among persons examined at forensic autopsy at the Jikei University School of Medicine. The HW, BH and BW of each subject were measured. Body surface area (BSA) in square meters was calculated from BH in centimeters and BW in kilograms with Takahira's equation. We found allometric relations between HW and BSA represented by these equations: HW=BSA(1.441) x 168.200 for males and HW=BSA(1.367) x 161.970 for females. For practical use, we developed a simplified scale with which normal HW can be easily and quickly calculated from BH and BW. Our simple technique can be used to estimate normal HW in routine autopsy practice.

The concept of the digital morgue as a 3D database.

The concept of the construction of a 3-dimensional database of a body structure, or a digital morgue, and its advantages to the field of forensic medicine was proposed. The digital morgue stores the body structure of each case as a 3D data set of sectioning planes of the whole body obtained from computer tomograms or magnetic resonance imaging figures. Furthermore, the medical virtual reality technique makes it possible to perform a simulated autopsy of the body in the digital morgue (virtual autopsy). Therefore, in the digital morgue, retrospective observation and quantitative analysis of the structural damage of the body are possible using high-dimensional medical imaging and medical virtual reality.

Immunohistochemical localization of P-selectin in the glomeruli from forensic autopsies.

The expression of the adhesion molecule P-selectin is known to be up-regulated in several vital organs including the kidney after trauma in experimental animals. We examined the expression of P-selectin in the kidney by immunohistochemistry in 41 forensic autopsies mainly from trauma cases. P-selectin immunoreactivity was present in the glomerular capillary endothelial tufts and cortical interstitial vascular endothelial cells. The P-selectin immunoreactivity in the glomeruli was not co-localized with CD41 (platelet marker) immunoreactivity. The antemortem interval between the onset of injury and death (AMI) was statistically significantly longer in the cases with more P-selectin-positive capillary endothelial tufts in the glomeruli. Our results show that P-selectin immunoreactivity exists in the glomerular capillary endothelial cells rather than platelets. Our results also indicate that the P-selectin expression increases in the glomerular endothelial cells of the human kidney with the longer duration of the state under injury.

An autopsy case of sudden death in a patient with idiopathic scoliosis.

A 38-year-old woman with idiopathic scoliosis (right convex thoracic scoliosis, 78 degrees; left convex lumbar curvature, 75 degrees) died suddenly. Forensic autopsy and histopathologic examination revealed chronic congestive oedema, numerous cavities and atrophic changes of heart. These changes, including both respiratory changes and biventricular failure caused by hypoplastic cardiac changes, were due to a deformed thoracic cage. This case illustrates that not only abnormalities of respiratory function and cor pulmonare, but also hypoplastic cardiac changes, may cause sudden death in a patient with untreated scoliosis.

Incomplete decapitation of a motorcyclist from hyperextension by inertia: a case report.

This is a rare case involving a motorcyclist. A 57 year old motorcycle rider wearing a full face type helmet, suffered incomplete decapitation. The autopsy findings revealed a wide lacerated wound accompanied by extension marks in the front neck, atlanto-occipital dislocation and complete transection of the brainstem. According to the police traffic report, the man's head was stationary at the moment of impact and the remainder of the body continued in a backward motion. We concluded that the inertia of the torso caused hyperextension of the neck and subsequent incomplete decapitation.

3D and 4D atlas system of living human body structure.

A reference system for accessing anatomical information from a complete 3D structure of the whole body "living human", including 4D cardiac dynamics, was reconstructed with 3D and 4D data sets obtained from normal volunteers. With this system, we were able to produce a human atlas in which sectional images can be accessed from any part of the human body interactively by real-time image generation.

Simulator for virtual surgery using deformable organ models and force feedback system.

This paper describes a real-time surgery planning system using virtual reality techniques. This system allows us to simulate incision of skin and organs which respond as elastic objects with surgical tools in virtual space. Inner structures such as blood vessels and lesions can be seen and manipulated in the simulation. In addition to these functions we attempted to add a feedback function that responds to the operator's hands. We developed a force feedback device to manipulate the elastic organ model based on pressure from the operator's fingers.

[Sudden unexpected natural death from a viewpoint of forensic pathology].

Sudden unexpected natural death (SUND) has several characteristics, such as unknown clinical history, very short course to death, evidence of trauma, interference of postmortem changes and social implications of diagnosis. From these points, SUND involves important challenges in forensic pathology. Presented here are the highlights of our SUND studies which allow scientific speculation into the antemortem pathophysiological course to death and a subsequent accurate diagnosis of the cause of death in SUND cases. 1. Forensic problems of SUND of unknown etiology 1) Do sudden infant death syndrome (SIDS) studies continue endlessly? In Japan there are many cases of sudden unexpected infant death (SUID) which were regarded as SIDS, often without postmortem examination. Pure SIDS should be a diagnosis of exclusion under thorough postmortem examination. Additionally, many SIDS studies have focused on pathogenesis of pure SIDS based on the analysis of so-called SIDS cases described above. In this sense, SIDS studies may continue forever. To clarify whether SIDS is an onion type, that is a heterogeneous disease entity, or bamboo shoot type, a single disease entity with a single cause, it is more vital to accurately search autopsy findings to exclude the cause of death, rather than to study pathogenesis of SIDS. Thereafter, pure SIDS will be carved in relief and we could study the pathogenesis, if it remains in the future. Present in 40% of our SUID cases examined was the existence of viral infection as a cause of death. 2) Pokkuri disease It has long been believed that the main branches of coronary arteries in Pokkuri-disease cases are macroscopically hypoplastic and cause sudden cardiac death. However, our two-dimensional morphometric analysis of the main branches, such as wall thickness, degree of stenosis, lumen area, area within internal elastic lamina, showed no significant differences between Pokkuri-disease cases and age and sex-matched control cases. 2. Information for grasping antemortem pathophysiological state in SUND cases 1) Standardization of the degree of cardiac hypertrophy based on heart weight. In the course of our preliminary examination, we found that heart weight correlates significantly with body length and weight. Therefore, we tried to standardize the range of normotrophy, hypertrophy and hypoplasia/atrophy of the heart based on the correlation between heart weight and body type index calculated by body length and weight (Broca's index). 2) Evaluation of the clinical laboratory data in cadaveric blood. We examined 32 clinical laboratory parameters in cadaveric blood samples obtained from 192 autopsy cases. Behaviour of the laboratory parameters in cadaveric blood in relation to postmortem interval was divided into four types: increased, decreased, no particular tendency and remaining between upper and lower normal value. Parameters included in the last type, which is a useful tool for speculation of antemortem pathophysiology were T-Bil, TTT, ZTT, BUN, Cre, UA, alpha 1- and beta 2-microglobin, T-Chol, GHA1c, TP, A/G, Hb and Hct. A case was demonstrated in which values of clinical laboratory parameters in agonar stage were the same as in cadaveric blood obtained at autopsy. This indicates that caution is necessary in evaluating clinical laboratory data in agonar patients in the emergency room. 3) Diagnostic evaluation of immunohistochemical myoglobin staining in the kidney In order to evaluate the diagnostic value of myoglobin (Mb) staining in the kidney in medicolegal autopsy cases, Mb staining was carried out on the kidney sections of 141 victims, including 59 natural and 82 unnatural deaths. At the same time, Serum and Urine GFR parameters were measured and systemic histological changes were observed on some sections of each kidney. The incidence of Mb positive cases was 74.6% in unnatural, and 25.4% in natural death, indicating the importance of nontraumatic rhabdomyolysis in natural death cases.

[An autopsy case of accidental hanging during home care].

A 73-year-old man who had suffered from old myocardial and cerebral infarction for 4 years had been secured in wheelchair due to left hemiplegia and aphasia and also been received a home care of his wife. One day, his wife tied a cloth belt around his head and secured it to the wheelchair to prevent the flexion of his neck. One hour later, he was found dead by his wife. He also had slipped down in his wheelchair. The autopsy performed 24 hours after death revealed a ligature marks on the front of the neck. Petechial hemorrhages, visceral congestion and fluid blood, compatible with asphyxial death, were also found. Although severe cerebral cortical atrophy, old myocardial infarction, moderate to severe atherosclerosis and decubitus of the back were also found, they were not considered primary cause of death. No other anatomical or toxicological cause of death was present. Therefore, we concluded that the man died of accidental hanging. Recently, the home care of aged or handicapped patient is a social problem in Japan due to the increase in the number of elderly people. The death was caused by the inappropriate restraints used by his wife. This case suggests the importance of proper advice to non-professional caretakers from care professionals.