Detection of methamphetamine in mouse femurs exposed to high temperature.

Bone samples are valuable for examining the cause of death and circumstance leading up to death when body fluids are not available for forensic toxicological analysis. Examined were heat-induced changes in methamphetamine and amphetamine concentrations in femurs removed from methamphetamine-injected mice to determine if the burned bones could be used for toxicology testing. The femurs were heated at 100°C, 300°C, or 500°C for 10 or 30 min. The tissue structure of the heated femurs was preserved at 100°C for 30 min but was destructed at higher temperatures. Methamphetamine and amphetamine were detected in femurs heated at 100°C for 10 min, 100°C for 30 min, and 300°C for 10 min (with methamphetamine and amphetamine concentrations ranging from 0.36 to 35 µg/g and 0.54 to 47 µg/g, respectively). Methamphetamine and amphetamine were detectable when heated above their decomposition temperature as a result of limited heat transfer do to protection provide by the femoral muscle. Thus, the bone could be a useful analytical sample in cases of burn-related deaths, where it is difficult to collect body fluids.

Analysis of the pathogenesis of acute necrotizing esophagitis (black esophagus): A report of three autopsy cases.

Acute necrotizing esophagitis (ANE) is a rare condition characterized by black discoloration of the esophageal mucosa. We describe three autopsy cases of ANE, also known as black esophagus. The black discoloration was confined to the esophageal mucosa rather than to the gastric mucosa. The histological findings of brown pigmentation and acute inflammation led to an ANE diagnosis. The immediate cause of death was certified as ANE in all cases. In the three cases, one had hypertension, diabetes, and multiple cerebral infarctions, another had alcoholism, whereas the pre-existing condition was unknown in the remaining patient. Petechial hemorrhages were found on the gastric mucosa of all three patients as a finding of terminal hypothermia. In one case, frequent vomiting was observed prior to death. Blood alcohol was detected (the patient had been drinking immediately prior to death), and the onset of ANE was considered to have occurred several hours before death. The findings indicate that ANE occurs shortly before death in combination with frequent vomiting and terminal hypothermia in the setting of cerebrovascular disease or alcoholism.

Analyses of physical factors that contribute to the blood carboxyhemoglobin saturation in autopsy cases of house fire fatalities.

The authors analyzed data from forensic autopsies of 75 patients who died as a result of house fires to clarify the physical factors that affect blood carboxyhemoglobin (COHb) saturation. Blood COHb saturation levels were significantly lower in patients who survived in the hospital. No significant differences were found in the blood COHb saturation levels between patients who died immediately at the scene and those who were pronounced dead at the receiving hospital without heartbeat being restored. The COHb saturation levels were significantly different among the groups of patients classified by the amount of soot. Although age, coronary artery stenosis, and blood alcohol concentration did not significantly affect blood COHb saturation, on comparing patients who died in the same fire, lower COHb saturation was observed in two patients, one with severe coronary artery stenosis and other with severe alcohol intoxication. To accurately interpret blood COHb saturation during forensic autopsy, the heartbeat status (present or absent) at the time of the rescue and the amount of soot in the trachea must be determined. Low levels of COHb saturation may be observed in fatalities with severe coronary atherosclerosis or severe alcohol intoxication.

Analysis of autopsy cases involving individuals who experienced cardiopulmonary arrest immediately after sustaining minor head injuries.

The authors report five forensic autopsy cases involving individuals who experienced cardiopulmonary arrest immediately after sustaining minor head injuries. Heartbeat was restored in two patients after resuscitation by paramedics. During autopsy, three patients exhibited high blood alcohol levels indicating severe intoxication, two had an unknown blood alcohol status, and all five exhibited parietal bruising of the head. In addition to alcohol intoxication, blunt force impact to the parietal area of the head was believed to be related to the occurrence of cardiopulmonary arrest immediately after head trauma. The absence of secondary brain damage in patients who die from cardiopulmonary arrest immediately after head trauma should be taken into account when diagnosing the cause of death. Additionally, indications for bystander cardiopulmonary resuscitation should be considered for individuals who experience cardiopulmonary arrest due to head trauma.

Delayed death due to traumatic dissection of the common carotid artery after attempted suicide by hanging.

Traumatic dissection of the carotid arteries is a rare cause of delayed death due to hanging. We report a case of delayed death two and a half months following attempted suicide by hanging where the patient was able to talk after being released from neck compression. The cause of death was aspiration pneumonia due to cerebral infarction secondary to traumatic dissection of the left common carotid artery due to attempted suicide by hanging. Carotid artery injuries should be examined in patients who were able to talk after an unsuccessful suicide attempt by hanging but who later died.

Detection of cocaine and metabolites from mouse femur buried in soil.

Drug addicts are frequently involved in committing homicides, and burial in the ground is often performed by offenders for body disposal. Therefore, toxicological analyses of buried bones are vitally important for investigating the cause and circumstance of death. Cocaine concentrations in heart blood, femoral muscle, and femur were measured in mice after injections of 5, 15, and 30 mg/kg cocaine and in femurs buried in soil. The concentrations of cocaine in femurs (253.67-1345.31 ng/g) were higher than those found in heart blood (3.14-28.73 ng/mL) and femoral muscle (76.41-429.76 ng/g). The cocaine concentrations in buried femurs (54.83-388.68 ng/g) were significantly lower than those in unburied femurs (253.67-1345.31 ng/g). Further, cocaine was detected in femurs after being buried for 7-180 days in soil. These findings indicate that cocaine concentrations are higher in bone than in heart blood and femoral muscle and that the concentration decreases after burial in soil.

Quantification of Methamphetamine in Mouse Thighbones Buried in Soil.

Bone samples are used for analysis of drugs in decomposed or skeletonized bodies. Toxicological analyses of buried bones are important for determining the causes and circumstances of death. In this study, methamphetamine and amphetamine concentrations in heart blood, thigh muscles, and thighbones were analyzed using solid-phase extraction with liquid chromatography-tandem mass spectrometry. Methamphetamine concentrations in heart blood, thigh muscle, and thighbone ranged from 0.041 to 0.873 µg/mL, 0.649 to 2.623 µg/g, and 56.543 to 643.371 µg/g, respectively. Thighbone concentrations were significantly higher than those in heart blood or thigh muscles were. Methamphetamine concentrations in buried thighbone (4.010-45.785 µg/g) were significantly lower than those of unburied thighbones were (56.543-643.371 µg/g). Methamphetamine and amphetamine were detected in thighbones buried for 7-180 days. These findings indicate that the methamphetamine concentrations in bone are higher and decrease after burial in soil.

Evaluation of the morphological changes of gastric mucosa induced by a low concentration of acetic acid using a rat model.

Oral ingestion of concentrated acetic acid causes corrosive injury of the gastrointestinal tract. To assess the effects of a low concentration of acetic acid on gastric mucosa, we examined the gastric mucosal changes in rats at 1 and 3 days after the injection of 5% or 25% acetic acid into the gastric lumen. The area of the gastric ulcerative lesions in the 25% acetic acid group was significantly larger than that in the 5% acetic acid group. The lesion area was reduced significantly at 3 days after injection in the 5% acetic acid group, whereas no significant difference in lesion area was observed at 1 and 3 days in the 25% acetic acid group. Histologically, corrosive necrosis was limited to the mucosal layer in the 5% acetic acid group, whereas necrosis extended throughout the gastric wall in the 25% acetic acid group. At 3 days post-injection, the 25% acetic acid group showed widespread persistent inflammation, whereas the 5% acetic acid group showed widespread appearance of fibroblasts indicative of a healing process. These results indicate that a low concentration of acetic acid damages the gastric mucosa and that the degree of mucosal damage depends on the concentration of acetic acid.

Temporal and regional variations in accidental deaths of elderly people in Japan.

To ascertain the characteristics of accidental deaths of elderly people in urban and rural areas, we analyzed the deaths of elderly people over the 10-year period from 2000 to 2009, in three geographic areas: nationwide, in the 23 wards of the metropolis of Tokyo, and in Saga prefecture. In addition, to assess the regional variation in accidental deaths of the elderly, we aggregated the numbers of accidental deaths of elderly people for each of Japan's prefectures in the year 2009 and categorized the deaths by accident type. The results showed that nationwide, deaths due to threats to breathing, falls, and drowning and submersion are increasing, while deaths due to transport accidents are decreasing, indicating a need for measures to prevent deaths from accidents other than transport accidents. In the urban areas of Tokyo's 23 wards, there is an increasing incidence of deaths due to falls, which is likely due to the high number of structures such as buildings and railway stations that elderly people need to negotiate. In urban areas, measures to reduce the incidence of accidental deaths need to focus on improving the physical environment to help prevent falls. In the rural locality of Saga prefecture, increasing numbers of elderly people are dying by drowning and submersion. The results of analysis of accidents in all prefectures of Japan by accident type show that the causes of accidental deaths of elderly people vary regionally, suggesting that accident prevention measures for elderly people need to consider the characteristics of the locality.

A rat model of changes in dural mast cells and brain histamine receptor H3 expression following traumatic brain injury.

Mast cells can secrete histamine in response to extrinsic stimuli. Histamine plays a role in the development of brain edema and can induce histamine receptor H3 (HRH3) expression in the brain to provide protective feedback effects against histamine neurotoxicity. We investigated time-dependent changes in dural mast cell numbers and HRH3 expression in the brain for one to 14 days after traumatic brain injury in a controlled cortical impact model in the rat. The number of tryptase-immunoreactive dural mast cells at the site of impact was significantly decreased one and four days after the injury. Furthermore, immunoreactivity and messenger RNA (mRNA) expression of HRH3 at the underlying cortical contusion site were significantly increased one and four days after the injury. These data suggest that histamine released from degranulated unstainable mast cells induces a transient increase in presynaptic autoinhibitory HRH3 immunoreactivity and mRNA expression as a mechanism to counteract histamine neurotoxicity.

Analysis of pituitary lesions in fatal closed head injury.

We analyzed forensic autopsy findings of 66 consecutive patients with fatal closed head injury who survived up to 48 days after trauma to ascertain the causal factors and the time course of development of posttraumatic pituitary lesions. Pituitary lesions were identified in 27 patients. In patients with pituitary lesions, posterior lobe hemorrhage was observed in 21 patients, followed by anterior lobe hemorrhage in 10 patients and anterior lobe infarct in 7 patients. Comparisons between patients with and without pituitary lesions showed that falls and subdural hematoma were significantly frequent in patients with pituitary lesions. Immunohistochemistry of neurophysin showed increased immunoreactivity in the hypothalamus of patients with pituitary lesions and brain edema, providing morphologic evidence of pituitary dysfunction. Hemorrhage in the anterior or posterior lobe was identifiable in patients with short survival periods, whereas infarct in the anterior lobe appeared in patients surviving at least 14 hours. These data further our understanding of the mechanisms of pituitary dysfunctions and help in the estimation of the survival period after head trauma.

Accidental deaths occurring in bed: review of cases and proposal of preventive strategies.

The bed is thought to be a safe place, but posses a number of risks that can cause deaths. To identify the causes of accidental death in bed and propose strategies for the prevention of further accidents, we surveyed and analyzed the literature on accidental deaths in bed from Japan and abroad, as well as legal cases related to accidental death in bed in Japan. A search of the medical literature in Japan (1983-2007), abroad (1976-2007), and Japan's legal cases (1989-2007) located 39 cases. The vast majority of accidental deaths in bed occur among infants and elderly individuals with neurologic disorders. The main causes of death within these two groups are head injuries caused by falls from a bed and asphyxia caused by pressure to the neck when wedged against a bed rail. It is necessary to focus on prevention of falls from bed and prevention of asphyxia caused by bed rails in the case of infants and elderly individuals with neurologic disorders. Infants should be placed to sleep in beds designed for their ages and placed on their back. Elderly individuals need to sleep in beds with properly fitting bed rails to reduce wedging.

Frequent detection of stomach contents in accidental drowning.

We analysed forensic autopsies of 536 consecutive adults to determine the relationship between the presence of stomach contents and the manner of death. Stomach contents were identified in 27 (79.4%) of 34 accidental drownings and in 22 (43.1%) of 51 suicidal drownings (P < 0.01). Accidental drowning was the manner of death most frequently associated with the presence of stomach contents, and stomach contents were found significantly more often in this type of death than in suicidal drowning. These findings indicate that food intake is a factor possibly related to accidental drowning and suggest that fasting may be required before swimming or taking a bath to prevent accidental drowning.

Changes in the brain after intracerebral implantation of a lead pellet in the rat.

In gunshot wounds to the head, the bullet containing neurotoxic lead may remain in the brain after trauma, and brain damage is therefore anticipated. We developed an animal model incorporating a lead ball implanted in the brain, or a glass ball as a control, and analyzed histological and biochemical changes in the brain for 28 days after surgery. The concentration of lead in the brain increased with time after implantation of the lead ball, while lead was not detected in brains implanted with a glass ball. A number of changes were noted following implantation of the lead ball. The number of neutrophils increased significantly at 7-28 days, while the number of macrophages also increased significantly with time. The number of neurons was significantly decreased by 28 days, and apoptotic cells were identified at 14-28 days. Expression of genes encoding N-methyl-d-aspartate receptors, which are related to cognitive function and help regulate apoptosis, was significantly suppressed at 7-21 days after implantation. Expression of metallothionein protein increased significantly with time. Metallothionein detoxifies lead and its overexpression is a known method of protection against lead neurotoxicity. These findings indicate that intracerebral lead induces neuronal degeneration that is attributable in part to the inflammation and apoptosis caused by leached lead. Although the severity of the brain damage primarily depends on the destructive effect of the moving bullet, the results of this study indicate that lead leaching from the residual bullet also damages the brain.

Hyperthermia combined with ethanol administration induces c-fos expression in the central amygdaloid nucleus of the mouse brain. A possible mechanism of heatstroke under the influence of ethanol intake.

Heatstroke is defined as a core body temperature that rises above 40.6 degrees C and is accompanied by mental status abnormalities such as delirium, convulsions, or coma resulting from exposure to environmental heat. There is fairly wide agreement that ethanol intake is a predisposing factor in heatstroke. This study was performed to identify the brain changes induced by heatstroke, using a mouse hyperthermia model with and without preceding ethanol administration. Exposure to heat of 42 degrees C until the core temperature reached to 43 degrees C followed by exposure to 37 degrees C for 15 min decreased the levels of partial pressures of O(2) in blood. Preceding ethanol administration and heat exposure induced hypotension, severe metabolic acidosis and respiratory failure, and, accordingly, produced heatstroke. Immunohistochemistry of the brains showed that preceding ethanol administration increased the number of c-fos-immunoreactive neurons, as a marker of neuronal activation, in the central amygdaloid nucleus, which is involved in thermoregulation. These results indicate that combined effects of ethanol and heat exposure induce heatstroke that is associated with activation of the central amygdaloid nucleus, implicating the pathophysiology and mechanisms of heatstroke under the influence of ethanol intake.

Morphological analysis of glutaraldehyde-fixed vimentin intermediate filaments and assembly-intermediates by atomic force microscopy.

Atomic force microscopy (AFM) was used to study the morphology of vimentin intermediate filaments (IFs) and their assembly intermediates. At each time after initiation of IF assembly in vitro of recombinant mouse vimentin, the sample was fixed with 0.1% glutaraldehyde and then applied to AFM analysis. When mature vimentin IFs were imaged in air on mica, they appeared to have a width of approximately 28 nm, a height of approximately 4 nm and a length of several micrometers. Taking into account the probe tip's distortion effect, the exact width was evaluated to be approximately 25 nm, suggesting that the filaments flatten on the substrate rather than be cylindrical with a diameter of approximately 10 nm. Vimentin IFs in air clearly demonstrated approximately 21-nm repeating patterns along the filament axis. The three-dimensional profiles of vimentin IFs indicated that the characteristic patterns were presented by repeating segments with a convex surface. The repeating patterns close to 21 nm were also observed by AFM analysis in a physiological solution condition, suggesting that the segments along the filaments are an intrinsic substructure of vimentin IFs. In the course of IF assembly, assembly intermediates were analyzed in air. Many short filaments with a full-width and an apparent length of approximately 78 nm (evaluated length approximately 69 nm) were observed immediately after initiation of the assembly reaction. Interestingly, the short full-width filaments appeared to be composed of the four segments. Further incubation enabled the short full-width filaments to anneal longitudinally into longer filaments with a distinct elongation step of approximately 40 nm, which corresponds to the length of the two segments. To explain these observations, we propose a vimentin IF formation model in which vimentin dimers are supercoiling around the filament axis.