Immunohistochemical analysis of CD31 expression in myocardial tissues from autopsies of patients with ischemic heart disease.

CD31, a transmembrane protein expressed on endothelial and hematopoietic cells, plays important roles in leukocyte trafficking, mechanotransduction, angiogenesis, vascular permeability, and regulation of cellular responsiveness. CD31 immunoreactivity is employed as a sensitive and specific endothelial marker in diagnostic pathology. In this study, CD31 expression in myocardial tissues from deceased patients with ischemic heart disease and a mouse model of acute myocardial infarction were examined by immunohistochemical staining. We examined 24 neutral formalin-fixed, paraffin-embedded myocardial tissue samples obtained within 48 h postmortem from the autopsies of patients who were diagnosed with ischemic heart disease. CD31 expression was observed in vascular endothelial and endocardial cells. In necrotic myocardium, diffusion of CD31 antigen was observed. Elevated CD31 expression was observed around myocardial cells undergoing remodeling, suggesting that endothelial proliferation occurred at these sites. In contrast, fibrotic myocardial foci did not show upregulated CD31 expression. The same CD31 expression characteristics as those observed in the human samples were observed in the mouse model. CD31 immunostaining as an endothelial and microvasculature marker may be a useful complement to conventional staining techniques currently used in the diagnosis of ischemic heart disease, and may allow the timing and process of myocardial remodeling to be analyzed in detail.

Discrimination method of seven species pufferfish of the genus Takifugu using DNA chromatography.

Identifying poisonous plants and animals is very important because they not only can cause food poisoning, but also can be eaten for the purpose of suicide. A pufferfish is a poisonous fish that contains tetrodotoxin. In Japan, 136 pufferfish poisoning cases occurred from 2015 to 2019, but in many cases, the specific species involved was unidentified. To address this, we focused on a rapid and simple DNA chromatography technology called Single-stranded Tag Hybridization (STH). We collected seven pufferfish species of the genus Takifugu and designed species-specific primers as target regions of cytochrome c oxidase subunit I (COI) and cytochrome b with a specific base sequence at the 3' end. STH-PCR was performed in two separate reactions. After mixing the PCR products, a developing solution was added to perform chromatograph development and the results were visually analyzed. Specific lines were detected in all seven species. The pufferfish species could be properly determined using between 0.1 ng and 50 ng of template DNA. The PCR product length was 85-149 bp, making it very resistant to degradation. The species could be properly identified even in a mixture of multiple pufferfish species DNA. Furthermore, verification was performed using the supernatants of digested samples with artificial gastric juice and processed foods. Extracted DNA was obtained in all but the highly roasted fins, enabling discrimination. Overall, we applied a novel DNA chromatography detection system capable of discriminating seven species of the genus Takifugu, which have closely related DNA sequences.

Effect of FURIN SNP rs17514846 on coronary atherosclerosis in human cardiac specimens: An autopsy study of 106 cases.

BACKGROUND: Coronary artery disease (CAD), including coronary atherosclerosis (CAS), is one of the most common causes of death. The FURIN SNP rs17514846 is assumed to be a risk factor for CAD. We evaluated this relationship using autopsy specimens and autopsy data, such as the histopathological degree of CAS. MATERIALS AND METHODS: A total of 106 samples were genotyped from obtained blood samples. Myocardial and coronary arterial FURIN levels were quantified by ELISA. The degree of CAS was classified histopathologically according to the Stary classification, and the localization of FURIN was examined by immunostaining. The obtained data were analyzed statistically. RESULTS: FURIN expression was widely observed in the myocardium, vascular smooth muscle cells, endothelial cells, adipocytes, and macrophages. FURIN level in the myocardium of cases with the AA genotype at the FURIN SNP rs17514846 was higher than that in CC cases. Additionally, FURIN levels in both coronary arteries and myocardium were higher at the early stage of CAS than at the late stage microscopically. CONCLUSION: Our study suggested that the A allele of rs17514846 is associated with higher FURIN level in the heart and that FURIN exhibits a higher level in the early stage of CAS. These findings deepen our understanding of the mechanism of CAS.

Immunohistochemical analysis of vimentin expression in myocardial tissue from autopsy cases of ischemic heart disease.

Vimentin is a type III intermediate filament cytoskeletal protein that is expressed mainly in cells of mesenchymal origin and is involved in a plethora of cellular functions. In this study, myocardial tissues from patients with ischemic heart disease and a mouse model of acute myocardial infarction were subjected to immunohistochemistry for vimentin. We first examined 26 neutral formalin-fixed, paraffin-embedded myocardial tissue samples from autopsies of patients that were diagnosed with ischemic heart disease within 48 h postmortem. Myocardial cells were negative for vimentin, whereas non-myocardial cells, including vascular endothelium, vascular smooth muscle, fibroblasts, nerve fibers, adipocytes and mesothelial cells, showed positivity. Elevated vimentin expression was observed around myocardial cells undergoing remodeling, suggesting fibroblastic and endothelial proliferation in these locations. By contrast, myocardial foci that were completely fibrotic did not show upregulated vimentin expression. Inflammatory foci including macrophages and neutrophils were clearly visualized with vimentin immunostaining. The same vimentin expression phenomena as those found in human samples were observed in the mouse model. Our study indicates that immunostaining of vimentin as a marker for myocardial remodeling and the dynamics of all non-myocardial cell types may be useful for supplementing conventional staining techniques currently used in the diagnosis of ischemic heart disease.

Quantitative analysis of thiamylal and its metabolite secobarbital using liquid chromatography-tandem mass spectrometry in adipose tissue, serum, and liver.

Thiamylal is an ultrashort-acting barbiturate used for intravenous administration or general anesthesia induction. However, some cases of poisoning and suicide with thiamylal administration have been reported. Additionally, there are few reports on its analysis in the organs and adipose tissue, which requires purification by column chromatography and evaporation. A rapid and sensitive method was developed for quantifying thiamylal and its metabolite, secobarbital, in the adipose tissue, serum, and liver using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Samples were prepared using modified QuEChERS extraction. For adipose tissue samples, an acetonitrile-hexane partitioning step was added to the extraction. This method was applied to investigate a suspected self-poisoning autopsy case. The quantitation accuracy for thiamylal added to porcine pericardial fat (0.18 µg/g), human serum (0.015 µg/mL), and porcine liver (0.18 µg/g) was 103%, 113%, and 95.3%, respectively. The quantitation limits calculated for porcine pericardial fat, human serum, and porcine liver at a signal-to-noise ratio of 10 were 0.06 µg/g, 0.005 µg/mL, and 0.06 µg/g, respectively. In addition, the thiamylal and secobarbital levels in the forensic autopsy case were 140 and 1.5 µg/g, respectively, in myocardial fat; 3.5-4.9 and 0.12-0.20 µg/mL, respectively, in serum; and 6.2-42 and 0.58-1.1 µg/g, respectively, in liver tissue. Thiamylal is especially distributed in the adipose tissue. The thiamylal-to-fat ratio may help estimate the time from administration to death. The developed modified QuEChERS extraction method with acetonitrile-hexane partitioning is suitable for analyzing hydrophobic compounds, such as thiamylal, in the adipose tissue.

Immunohistochemical analysis of von Willebrand factor expression in myocardial tissues from autopsies of patients with ischemic heart disease.

von Willebrand factor (VWF) plays a crucial role in hemostasis and thrombosis. VWF is involved in platelet attachment to the subendothelium, serving as a carrier protein for coagulation factor VIII. In this study, myocardial tissues from deceased patients with ischemic heart disease and a mouse model of acute myocardial infarction were subjected to immunohistochemistry to determine VWF expression. We examined 28 neutral formalin-fixed, paraffin-embedded myocardial tissue samples obtained from the autopsies of patients who were diagnosed with ischemic heart disease within 48 h postmortem. Most myocardial cells were negative for VWF, although some cells showed nonspecific positivity. Elevated VWF expression was observed around myocardial cells undergoing remodeling, suggesting that endothelial proliferation occurred at these sites. In contrast, completely fibrotic myocardial foci did not show upregulated VWF expression. Positivity in fibrin deposition and hemorrhagic sites was observed. The same VWF expression characteristics as those observed in the human samples were observed in the mouse model. VWF immunostaining as an endothelial marker may be a useful supplementation to conventional staining techniques that are currently used in the diagnosis of ischemic heart disease in terms of examining the timing of myocardial remodeling in detail and highlighting the remodeling process.

Immunohistochemical analysis of thrombomodulin expression in myocardial tissue from autopsy cases of ischemic heart disease.

Thrombomodulin is a transmembrane glycoprotein that is ubiquitously expressed on the surface of vascular endothelial cells. Thrombomodulin exerts its anticoagulant effects by combining with thrombin, activating protein C, and inactivating the coagulation factors FVa and FVIIIa. Clinically, thrombomodulin is also known as a marker of vascular injury because it circulates freely in response to endothelial injury. In this study, myocardial tissue from cases of ischemic heart disease was subjected to immunohistochemistry by thrombomodulin. We examined 40 neutral-formalin-fixed, paraffin-embedded myocardial tissue samples from autopsy cases that were diagnosed with ischemic heart disease (within 48 h postmortem). Thrombomodulin expression was observed in vascular endothelial cells between myocardial cells and in mesothelial cells of the epicardium. In necrotic myocardium, diffusion of thrombomodulin, which reflected endothelial injury, was observed. Upregulated thrombomodulin expression was observed around myocardial cells under ongoing remodeling, which suggested endothelial proliferation in these locations. Completed fibrotic foci of the myocardium did not show upregulated thrombomodulin expression. In a mouse model of acute myocardial infarction, the same phenomena as that found in human samples were observed by immunohistochemistry of thrombomodulin. Immunostaining of thrombomodulin, as a marker for endothelial injury or myocardial remodeling, may be useful for supplementing conventional staining techniques in the diagnosis of ischemic heart disease in forensic pathology.

Autopsy case of Rosai-Dorfman disease presenting as fibrinous pericarditis.

Rosai-Dorfman disease (RDD) is a rare non-Langerhans cell histiocytosis that is characterized histopathologically by accumulation of CD68-positive, S100-positive, and CD1a-negative histiocytes. Cardiac involvement of RDD is rare. We report here an autopsy case of cardiac involvement of RDD presenting as fibrinous pericarditis. A 14-year-old Japanese boy complained of loss of appetite and breathing difficulty when lying down. He was found dead on his back in his bedroom. One year before his death, he was diagnosed with RDD after skin biopsy. At autopsy, the deceased was 153 cm in height and weighed 38 kg with systemic edema. He had flat pigmented light-brown spots, as well as many pale reddish-brown papules on the abdomen and both thighs. Cervical and mediastinal lymphadenopathy was observed. A large amount of pleural and ascitic fluid was observed. The spleen weighed 381.9 g and showed splenomegaly. The heart weighed 620 g and showed acute fibrinous pericarditis with adhesion. Abundant fibrin was observed on the epicardial surface. The infiltrating cells were CD68-positive, S100-positive, and CD1a-negative histiocytes. The skin and spleen showed histiocytic involvement. Systemic edema, large amounts of pleural and ascitic fluid, a high brain natriuretic peptide level in blood, and hemosiderin-laden macrophages in the lungs suggested chronic heart failure. We speculate that the cause of death was extranodal cardiac involvement of RDD with chronic heart failure. This case highlights the need for forensic pathologists to perform a complete autopsy to determine the cause of sudden death when cardiac involvement of RDD is present.

Anterior Tricuspid Leaflet Cleft in an Adult Male: An Autopsy Case Report.

The deceased was a 44-year-old male who was treated for a suspected Ebstein's anomaly observed using transthoracic echocardiogram. He was found dead in his bed at home. Autopsy revealed that the septal tricuspid leaflet was intact; however, a large anterior tricuspid leaflet cleft and right atrioventricular cavity dilation were observed. Pathological examination revealed a normal tricuspid valve, except for the presence of a cleft with local fibrosis of the left ventricle papillary muscle and hemosiderin-containing macrophages at both lungs. There were no other abnormalities that may have led to death. It was concluded that he died a cardiac death based on the right heart overload associated with the anterior tricuspid leaflet cleft. This case indicates the possibility that the anterior tricuspid leaflet cleft can cause death and also highlights the necessity of a detailed autopsy to accurately diagnose the cause of death.

Stability of ten psychotropic drugs in formalin-fixed porcine liver homogenates.

In forensic toxicology studies, drug concentrations must be estimated by the analytical data of formalin-fixed tissues if fresh or frozen tissue specimens are not available. We wished to investigate the stability and time-course of metabolism/degradation of drugs in formalin-fixed tissues using porcine liver homogenates (PLHs) instead of human tissue. Ten psychotropic drugs (amitriptyline, brotizolam, diazepam, diphenhydramine, estazolam, etizolam, levomepromazine, paroxetine, quetiapine and triazolam) were added to PLHs. After the PLHs had been fixed with neutral buffered formalin at room temperature, the concentrations of the drugs in the PLHs were determined by liquid chromatography-tandem mass spectrometry after 3 days, 1 week, 2 weeks, 4 weeks, 2 months, 4 months and 6 months. After 6 months, the residual ratio of amitriptyline, diphenhydramine and quetiapine was 80 %-95 %; that of diazepam, paroxetine and triazolam was 10 %-45 %; and that of brotizolam, etizolam and levomepromazine was 1 %-5 %. Estazolam was not detected from the first day of formalin fixation. These data suggest that the concentrations of drugs in PLHs measured after formalin fixation decreased to varying degrees compared with their initial concentrations. These time-dependent changes in drug concentration were due to degradation during preservation in formalin solution and metabolism by hepatic microsomal enzymes.

Rapid identification of Gloriosa superba and Colchicum autumnale by melting curve analysis: application to a suicide case involving massive ingestion of G. superba.

The plant species Gloriosa superba and Colchicum autumnale produce extremely poisonous colchicine as a major toxic metabolite. Almost all previous studies on colchicine poisoning have focused on drug analysis and clinical and pathological aspects. In this study, we developed a rapid, highly sensitive method to identify G. superba and C. autumnale. This method, which can distinguish between G. superba and C. autumnale using even minute amounts of plant material, is based on duplex real-time PCR in combination with melting curve analysis. To discriminate between the two genera of colchicine-containing plants, we designed new primer pairs targeting the region of the ycf15 gene, which is present in C. autumnale but not G. superba. By producing PCR amplicons with easily distinguishable melting temperatures, we were able to rapidly and accurately distinguish G. superba from C. autumnale. The new primer pairs generated no PCR amplicons from commercially available human DNA or various plant DNAs except for G. superba and C. autumnale. Sensitivity testing indicated that this assay can accurately detect less than 0.031 ng of DNA. Using our method in conjunction with colchicine drug analysis, we successfully identified G. superba in the stomach contents of a suicide victim who ingested massive quantities of a colchicine-containing plant. According to these results, duplex real-time PCR analysis is very appropriate for testing forensic samples, such as stomach contents harboring a variety of vegetables, and enables discrimination between G. superba and C. autumnale in forensic and emergency medical fields.

Development of a modified p-dimethylaminocinnamaldehyde solution for touch DNA analysis and its application to STR analysis.

We developed an acid-free p-dimethylaminocinnamaldehyde (DMAC) solution containing silicone oil that was suitable for spraying on clothing for analysis of biological samples such as touch DNA. We investigated the effect of this solution and irradiation with blue light emitting diode (LED) light on short tandem repeat (STR) analysis. To examine the effect of adding acid to the DMAC solution on visualizing biological samples, saliva sample was deposited on T-shirt. The T-shirt was sprayed with acid-added DMAC or acid-free DMAC solution and left for 2 h before irradiation with the blue LED light. We observed no differences between the fluorescence intensities achieved with these two solutions. To examine the effect of acid addition to the DMAC solution on STR analysis, sweat samples were smeared on glass slides and dried. The slides were sprayed with acid-added or acid-free DMAC solution and irradiated with the blue LED light. Samples were collected from the slides with swabs, and DNA was extracted from each sample using a PrepFiler Express™ Forensic DNA Extraction Kit and quantified using a Human DNA quantification kit (Takara RR281). The extracted DNA was amplified using an AmpFℓSTR® Identifiler® Plus PCR Amplification Kit for STR typing. We found that addition of acid to DMAC had little effect on DNA contained in the biological samples and STR analysis. To investigate whether DMAC could be used to visualize biological samples on clothes, saliva, sweat, and finger and palm prints were deposited on separate T-shirts. Biological samples were treated with DMAC and observed after 2 h, 1, 2, or 3 days under the blue LED. All biological samples were visualized and emitted fluorescence after 2 h. To examine the effects of the DMAC solution and LED irradiation on STR analysis, including DNA extraction, quantification, and STR typing, saliva and sweat were smeared on glass slides and dried. Touch DNA samples were deposited on glass slides directly. The slides were then sprayed with DMAC solution, sprayed with DMAC solution and irradiated with the blue LED, or left untreated. Samples were collected from the slides with swabs, and DNA was extracted, quantified, and amplified using the above kits. These results suggest that the DMAC solution and blue LED light will have no adverse effects on STR analysis. Therefore, this method will be very useful for touch DNA analysis in forensic investigations.

sjTREC quantification using SYBR quantitative PCR for age estimation of bloodstains in a Japanese population.

Individual age is a phenotypic trait that provides useful information in forensic investigations. Levels of signal joint T-cell receptor rearrangement excision circle (sjTREC) in human peripheral blood are known to decline with increasing age. The advantages of sjTREC quantification are the simple procedures and highly accurate age estimation results. Whereas TaqMan quantification PCR (qPCR) is widely used for sjTREC quantification, SYBR qPCR assay is not routinely used for evaluating ethnic data. Therefore, we focused on the advantages of the SYBR qPCR assay, which is cheaper and simpler to set up than the TaqMan probe assay. In this study, we developed a SYBR qPCR assay for sjTREC quantification from bloodstains from a Japanese population and evaluated the strength of correlation between sjTREC levels and actual age. The results were obtained from 194 individuals ranging from 18 to 81 years old, and showed a negative correlation between sjTREC level and individual age (r =  -0.786). The equation for age estimation was Age =  -6.27 dCt (CtTBP - CtsjTREC) - 25.841 with standard error ±8.0 years. Furthermore, this formula for the SYBR assay can be applied to not only fresh bloodstains, but also whole blood and bloodstains up to 1 month old. These results indicate that SYBR qPCR is an effective method for age estimation from bloodstains, and its practicality and affordability make it an attractive sjTREC quantification technique.

Autopsy Case of a Penetrating Wound to the Left Cerebral Hemisphere Caused by an Accidental Shooting With a Crossbow.

A crossbow is a bow that shoots an arrow when a gun-like trigger is pulled. Deaths caused by accidental crossbow shootings are extremely rare. Here we describe an autopsy case of a penetrating wound to the left cerebral hemisphere caused by an accidental shooting with a crossbow. A man in his early 60s who lived with his wife and had used crossbows for 20 years as his hobby was found one early morning in the shed of his house, collapsed and bleeding from the head and neck. He was taken to a hospital and died after approximately 3 days of conservative treatment. At autopsy, a penetrating wound between the upper part of the left anterior neck and the left frontoparietal region was evident. Traumatic intracerebral hematoma was observed in the left frontal lobe, and severe traumatic subarachnoid hemorrhage was present throughout the brain. Cerebral contusion and hematoma without any organization were noted around the penetration. The cause of death was determined to be cerebral contusion and intracerebral hematoma due to the penetrating wound by the crossbow arrow. He was probably trying to load an arrow into the crossbow by placing it on the floor, pointing upward, and made a mistake in its operation that resulted in the shooting of the arrow. This case is unique because it was a rare accidental death caused by a crossbow arrow, and a detailed histopathological examination was performed.

Development of a simultaneous identification method for 13 animal species using two multiplex real-time PCR assays and melting curve analysis.

We developed a simple and rapid method for animal species identification in the forensic science field based on mitochondrial DNA using two multiplex real-time PCRs and analysis of the resultant SYBR Green I melting curves. This method was designed to identify nine domestic animals simultaneously (dog, cat, rabbit, cattle, pig, chicken, goat, sheep and horse) and four wild animals (deer, raccoon-dog, monkey and bear) by comparing the different melting temperatures of the amplicons produced from samples originating from each species. For this analysis, we targeted various mitochondrial genes, including those encoding cytochrome b (cytb), NADH dehydrogenase 5 (ND5), cytochrome c oxidase 3 (COX3), tRNA-ND5, and tRNA-ATP synthase 8 (ATP8). For practical applications, this study presents a validation of this assay including its specificity, sensitivity and robustness. The limits of detection in the multiplex reactions were 10 pg for eight of the nine animals, excluding horse (1 pg for horse). The method was able to correctly identify the animal species from artificial forensic samples including blood stains, saliva, hair and bone, and samples digested in artificial gastric fluid, and for 17 forensic casework samples. The data from the multiplex real-time PCR assays are obtainable only 30 min after DNA extraction of the samples, making the assays useful for screening samples containing DNA from unknown animal origin in the forensic field.

An autopsy case of cardiac tamponade caused by a ruptured ventricular aneurysm associated with acute myocarditis.

We report an autopsy case of hemopericardium caused by rupture of a ventricular aneurysm associated with acute myocarditis in an infant boy aged 2 years and 10 months. Three days before his death, the patient developed fever. On the day of death, he described an urge to defecate and attempted to do so in an upright position. While straining to defecate without success for a prolonged period, he stopped breathing and collapsed. On autopsy, his heart weighed 91.7 g and cardiac tamponade was evident, the pericardial cavity being filled with 140 mL of blood that had come from a 1.5-cm-long rupture in a 2.7×1.5 cm ventricular aneurysm in the posterior left ventricular wall. Patchy grayish-white discoloration was noted in the myocardium. Histologically, CD3-positive T lymphocytic infiltration accompanied by pronounced macrophage infiltration was observed in the myocardium. Hemorrhagic necrosis was detected in the area of the ventricular aneurysm. Staining for matrix metalloproteinase (MMP) expression revealed abundant MMP-2, MMP-7, and MMP-9. Polymerase chain reaction to detect viruses failed to identify any specific causative viruses in the myocardium. In this case of lymphocytic (viral) and histiocytic myocarditis with pronounced macrophage infiltration and upregulation of MMP expression, myocardial remodeling and associated wall weakening had resulted in formation and rupture of an aneurysm.

Rupture of massive coronary artery aneurysm resulting in cardiac tamponade.

Coronary artery aneurysm is a fairly uncommon clinical entity, which is defined by a characteristic dilatation that exceeds 1.5 times the width of normal adjacent coronary artery segments. In the present report, we describe a case of rupture of a massive coronary artery aneurysm. A man in his 40s was found dead in his bed. The pericardial cavity contained 270mL of blood with 428.2g of coagulation. Two true aneurysms of the right coronary artery were identified. A proximal aneurysm, adjacent to the right auricle, had ruptured on the right. A distal unruptured aneurysm was identified 5.1cm distal to the proximal ruptured aneurysm. Atherosclerosis of the coronary arteries and aorta was severe. The heart weighed 799.1g and showed concentric ventricular hypertrophy, myocardial thinning, and patchy fibrosis. Histological analysis showed that both aneurysms were purely atherosclerotic true aneurysms without considerable inflammation. The cause of death was determined as cardiac tamponade due to rupture of a giant coronary atherosclerotic aneurysm.

Estimates of exposure to cold before death from immunohistochemical expression patterns of HSP70 in glomerular podocytes.

Environmental factors such as outside temperature at the time of death are very important for forensic diagnoses and police investigations. In particular, death in a cold environment is associated with factors of forensic interest, including hypothermia, drowning in cold water, or postmortem body movement by a suspect. Hypothermia raises a special problem because of the difficulty of evaluation during autopsy. We describe here a unique method of estimating antemortem environmental temperature, involving the immunohistochemical analysis of HSP70 expression patterns in glomerular podocytes. Using this method, we found that HSP70 was present in glomerular podocytes at autopsy and that HSP70 was highly expressed, mainly in the nucleus of podocytes, in deaths associated with exposure to cold. Interestingly, this expression pattern was specific to death in a cold environment, including hypothermia and drowning in cold water. Analysis of the pattern of HSP70 expression in glomeruli may therefore be very useful in forensic diagnosis, for determining whether the antemortem environmental temperature was low. Moreover, immunohistochemical and real-time PCR assays of the molecular mechanism of HSP70 and HSF1 expression in glomeruli following exposure to cold indicated that HSP70 was rapidly translocated to the nucleus of podocytes following exposure to cold, but without new protein synthesis.