Changes in SARS-CoV-2 viral load and titers over time in SARS-CoV-2-infected human corpses.

High viral titers of infectious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been detected in human corpses long after death. However, little is known about the kinetics of infectious SARS-CoV-2 in corpses. In this case series study, we investigated the postmortem kinetics of infectious SARS-CoV-2 in human corpses by collecting nasopharyngeal swab samples at multiple time points from six SARS-CoV-2-infected patients after their death. SARS-CoV-2 RNA was detected by quantitative reverse transcription-polymerase chain reaction from nasopharyngeal swab samples collected from all six deceased patients. A viral culture showed the presence of infectious virus in one deceased patient up to 12 days after death. Notably, this patient had a shorter time from symptom onset to death than the other patients, and autopsy samples showed pathological findings consistent with viral replication in the upper respiratory tract. Therefore, this patient died during the viral shedding phase, and the amount of infectious virus in the corpse did not decrease over time up to the date of autopsy (12 days after death). The findings of this study indicate that the persistence of SARS-CoV-2 in corpses can vary among individuals and may be associated with the stage of the disease at the time of death. These important results complement many previously reported findings on the infectivity of SARS-CoV-2 at postmortem.

Evaluation of organophosphorus pesticide tyrosine adducts for post-mortem change by human serum albumin with liquid chromatography quadrupole orbitrap mass spectrometry.

Organophosphorus pesticides (OPPs) having a phosphate ester moiety, such as malathion (MA) and methidathion (DMTP), are widely used and have been detected in many fatal cases of accidental exposure or suicide in Japan. In forensic toxicology, the accurate determination of blood OPP concentration is mandatory to prove death by OPP poisoning. However, fatal pesticide concentration in blood at autopsy varies depending on the circumstances surrounding the dead body. In this study, we found that 16 OPPs were degraded by human serum albumin (HSA) in a temperature-dependent fashion. The mechanism underlying MA, DMTP, azinphos-methyl, etrimfos, fenthion (MPP), pirimiphos-methyl, (E)-dimethylvinphos, (Z)-dimethylvinphos, vamidothion, edifenphos (EDDP), fosthiazate, and pyraclofos degradation involves the formation of adducts with tyrosine residues in HSA. The mass spectra obtained by liquid chromatography quadrupole Orbitrap mass spectrometry (LC-Q-Orbitrap-MS) revealed that phosphate ester amino acid adducts such as Y-adduct1, Y-adduct2, Y-adduct3, Y-adduct4, and Y-adduct5 were formed in HSA solution incubated with OPPs. These results indicate that the 16 OPPs are post-mortem changed by HSA. The detection of phosphate ester amino acid adducts such as Y-adduct1, Y-adduct2, Y-adduct3, Y-adduct4, and Y-adduct5, instead of MA, DMTP, azinphos-methyl, etrimfos, MPP, pirimiphos-methyl, (E)-dimethylvinphos, (Z)-dimethylvinphos, vamidothion, EDDP, fosthiazate, and pyraclofos per se, may be used to determine death by these OPPs poisoning.

Usefulness of powdered crown of mandibular first premolars in birth year estimation by radiocarbon dating.

BACKGROUND: Radiocarbon (14C), whose levels increased in the atmosphere between 1955 and 1963, accumulates in the enamel of human teeth only during the process of tooth formation and has been applied to estimate the birth year of unidentified corpses. However, enamel isolation from teeth is time-consuming and labor-intensive. Therefore, this study aimed to estimate the birth year using 14C in the crown of a single mandibular first premolar tooth. MATERIALS AND METHODS: Fourteen mandibular first premolars collected from forensic autopsies were analyzed. For nine teeth, each tooth was cut longitudinally: half of the tooth was enamel, and the other half was crown (1). For the other five teeth, the entire crown was used (2). Thereafter, the 14C concentration in each tooth was measured using accelerator mass spectrometry. RESULTS: The absolute error between the actual date of birth (DOB) and the estimated DOB was within the range of 1.0-8.8 years in the enamel of five teeth and 0.1-4.0 years in the crown halves of seven teeth (1). For the five teeth with entire crowns, the absolute errors ranged between 0.3 and 3.0 years (2). CONCLUSION: The absolute error of 14C-based year of birth estimation using the powdered crown of the mandibular first premolar teeth ranged between 0.1 and 4.0 years. Our method, which involves pulverizing an entire crown, eliminates the need for the equipment, time, and labor associated with enamel isolation. Therefore, 14C dating using powdered crowns of mandibular premolars can be useful for birth year estimation.

Genomic analysis of SARS-CoV-2 in forensic autopsy cases of COVID-19.

Numerous genomic analyses of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been conducted, highlighting its variations and lineage transitions. Despite the importance of forensic autopsy in investigating deaths due to coronavirus disease 2019 (COVID-19), including out-of-hospital deaths, viral genomic analysis has rarely been reported due in part to postmortem changes. In this study, various specimens were collected from 18 forensic autopsy cases with SARS-CoV-2 infection. Reverse-transcription quantitative polymerase chain reaction revealed the distribution of the virus in the body, primarily in the respiratory organs. Next-generation sequencing determined the complete genome sequences in 15 of the 18 cases, although some cases showed severe postmortem changes or degradation of tissue RNA. Intrahost genomic diversity of the virus was identified in one case of death due to COVID-19. The accumulation of single-nucleotide variations in the lung of the case suggested the intrahost evolution of SARS-CoV-2. Lung of the case showed diffuse alveolar damage histologically and positivity for SARS-CoV-2 by immunohistochemical analysis and in situ hybridization, indicating virus-associated pneumonia. This study provides insights into the feasibility of genomic analysis of SARS-CoV-2 in forensic autopsy cases and the potential for uncovering important information in COVID-19 deaths, including out-of-hospital deaths.

COVID-19 Analysis in Tissue Samples Acquired by Minimally Invasive Autopsy in Out-of-Hospital Deaths with Postmortem Degeneration.

Minimally invasive autopsy (MIA) is an alternative to a full autopsy for the collection of tissue samples from patients' bodies using instruments such as a biopsy needle. MIA has been conducted in many cases of coronavirus disease 2019 (COVID-19) and has contributed to the elucidation of the disease pathogenesis. However, most cases analyzed are hospital deaths, and there are few reports on the application of MIA in out-of-hospital deaths with varying extents of post-mortem changes. In this study, MIA and autopsies were performed in 15 patients with COVID-19 2-30 days after death, including 11 out-of-hospital deaths. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome detection by reverse transcriptase quantitative polymerase chain reaction using MIA samples was mostly consistent with autopsy samples, particularly lung tissue, even in out-of-hospital cases. MIA had high sensitivity and specificity (> 0.80). Histological examination of lung tissue obtained by MIA showed characteristics of COVID-19 pneumonia, with 91% agreement with autopsy samples, whereas localization of SARS-CoV-2 protein in lung tissue was indicated by immunohistochemistry, with 75% agreement. In conclusion, these results suggest that MIA is applicable to out-of-hospital deaths due to COVID-19 with various postmortem changes, especially when autopsies are not available.

Identification of postmortem paliperidone metabolite in human blood by LC-Q-Orbitrap-MS.

Paliperidone is a widely used antipsychotic agent detected in many fatal intoxications and suicide cases. In forensic toxicology, the accurate determination of blood paliperidone concentrations is required to prove death by paliperidone poisoning. However, the lethal concentration of paliperidone in blood at autopsy differs from that at the time of death. In this study, we found that paliperidone was decomposed by hemoglobin (Hb) through the Fenton reaction in a temperature-dependent fashion. The mechanism underlying paliperidone decomposition involves the cleavage of its C-N bond linker moiety. The mass spectra obtained by liquid chromatography-quadrupole orbitrap mass spectrometry revealed the formation of 6-fluoro-3-(4-piperidinyl)benzisoxazole (PM1) in Hb/H2O2 solution incubated with paliperidone, as well as in the blood of individuals who died from intentional ingestion of paliperidone. These results suggest that PM1 is the only metabolite produced from paliperidone as a result of temperature-dependent, postmortem changes induced by Hb via the Fenton reaction and may be useful as a biomarker to correct for the concentration of paliperidone in blood at the time of death in clinical cases.

High titers of infectious SARS-CoV-2 in corpses of patients with COVID-19.

OBJECTIVES: The prolonged presence of infectious SARS-CoV-2 in deceased patients with COVID-19 has been reported. However, infectious virus titers have not been determined. Such information is important for public health, death investigation, and handling corpses. The aim of this study was to assess the level of SARS-CoV-2 infectivity in the corpses of patients with COVID-19. METHODS: We collected 11 nasopharyngeal swabs and 19 lung tissue specimens from 11 autopsy cases with COVID-19 in 2021. We then investigated the viral genomic copy number by real-time reverse transcription-polymerase chain reaction and infectious titers by cell culture and virus isolation. RESULTS: Infectious virus was present in six of 11 (55%) cases, four of 11 (36%) nasopharyngeal swabs, and nine of 19 (47%) lung specimens. The virus titers ranged from 6.00E + 01 plaque-forming units/ml to 2.09E + 06 plaque-forming units/g. In all cases in which an infectious virus was found, the time from death to discovery was within 1 day and the longest postmortem interval was 13 days. CONCLUSION: The corpses of patients with COVID-19 may have high titers of infectious virus after a long postmortem interval (up to 13 days). Therefore, appropriate infection control measures must be taken when handling corpses.

Identification, measurement, and evaluation of blood concentrations of insulin glargine and insulin lispro by UPLC-MS-MS in a dead body suspected of insulin overdose.

Insulin preparations, which are drug treatments for diabetes, cause fatal hypoglycemia when an overdose is administered. Cases of homicide and suicide using these preparations have been reported and are of great forensic interest. However, there are few reports assessing the postmortem concentration of insulin preparations, and it is often difficult to determine the cause of death. In the present study, we report a case of a suspected insulin glargine and insulin lispro overdose for suicide. A woman in her 30s had a history of mental illness and diabetes. The day before her death, she reported to her boyfriend that she had taken large doses of insulin preparations and prescription drugs. An autopsy revealed no fatal injuries or lesions. Drug screening tests revealed several prescription drugs, none of which showed toxic concentrations. Analysis using LC-MS/MS detected insulin glargine in the peripheral and cardiac blood at 429 µU/mL and 1362 µU/mL, respectively, whereas insulin lispro was detected in both the peripheral and cardiac blood at levels below the lower limit of quantification (LLOQ; <50 µU/mL). The cause of death was considered likely to be hypoglycemia caused by an overdose of insulin glargine. Insulin glargine is rapidly metabolized after subcutaneous administration and is rarely detected in the blood when used at therapeutic doses. There are no other reports on the quantification of insulin glargine parent compounds in postmortem samples, and this case provides important data on postmortem blood concentrations of insulin glargine intoxication.

SARS-CoV-2 Transmission from Virus-Infected Dead Hamsters.

Although it has been 2.5 years since the coronavirus disease 2019 (COVID-19) pandemic began, the transmissibility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from a dead infected body remains unclear, and in Japan, bereaved family members are often not allowed to view in person a loved one who has died from COVID-19. In this study, we analyzed the possibility of SARS-CoV-2 transmission from a dead body using a hamster model. We also analyzed the effect of "angel care"--in which the pharynx, nostrils, and rectum are plugged--and embalming on reducing transmissibility from dead bodies. We found that SARS-CoV-2 could be transmitted from the bodies of animals that had died within a few days of infection; however, angel care and embalming were effective in preventing transmission from the dead bodies. These results suggest that protection from infection is essential when in contact with a SARS-CoV-2-infected dead body and that sealing the cavities of a dead body is an important infection control step if embalming is not performed. IMPORTANCE We found that SARS-CoV-2 could be transmitted from a dead body, presumably via postmortem gases. However, we also found that postmortem care, such as plugging the pharynx, nostrils, and rectum or embalming the corpse, could prevent transmission from the dead body. These results indicate that protection from infection is essential when handling infected corpses and that appropriate care of SARS-CoV-2-infected corpses is important.

Impact of the COVID-19 pandemic on pathological autopsy practices in Japan.

During the coronavirus disease 2019 (COVID-19) pandemic, autopsies have provided valuable insights into the pathogenesis of COVID-19. The precise effect of this pandemic on autopsy procedures in Japan, especially in instances unrelated to COVID-19, has not yet been established. Therefore, we conducted a questionnaire survey from December 2020 to January 2021 regarding the status of pathological autopsy practices in Japan during the first year of the COVID-19 pandemic. The questionnaire was sent to 678 medical facilities with pathologists, of which 227 responded. In cases where a confirmed diagnosis of COVID-19 was not made at the time of autopsy, many facilities counted them as suspected COVID-19 cases if pneumonia was suspected clinically. At around half of the sites, autopsies were prohibited for suspected COVID-19 cases. In addition, the number of autopsies of non-COVID-19 cases during the pandemic period was also investigated, and a significant decrease was observed compared with the incidence in the pre-pandemic period. The COVID-19 pandemic has affected not only the autopsies of COVID-19 cases but also the entire practice of pathological autopsies. It is necessary to establish a system that supports the implementation of pathological autopsy practices during the pandemic of an emerging infectious disease.

Methamphetamine-related forensic autopsy cases in a Japanese prefecture over a 7-year period: Characteristics of deaths and blood concentrations.

Understanding the actual conditions of methamphetamine (MA)-related death is important from the perspectives of criminal justice and public health. In this report, we review 104 cases of MA-related death handled by our departments between January 2014 and December 2020. Based on information from police and autopsy examinations, we classified the cases into the following categories: "accidental intoxication" ("MA only" and "multiple drugs or alcohol"), "fatal disease" ("definitively MA-related," "possibly MA-related," and "unlikely MA-related"), "accident," "suicide," "homicide," and "undetermined." The total number and annual trends for each category and their respective femoral blood concentrations were investigated. "Fatal disease" was the most common category (48 cases), followed by "suicide" (25 cases), "accidental intoxication" (14 cases), and "accident" (11 cases). "Definitively MA-related" in which MA may have played a role in their onset or exacerbation accounted for the majority of "fatal disease": 12 cases of heart disease, 4 cases of aortic dissection, 12 cases of cerebral hemorrhage, and 4 cases of subarachnoid hemorrhage. Cases classified as "definitively MA-related" died with lower femoral blood concentrations of MA compared with "MA only." Cases with "fatal disease" might have been misdiagnosed as "death by natural causes" if a proper autopsy and toxicology examinations were not performed. In death investigations, it is necessary to keep in mind that there are some MA-related deaths, and efforts should be made to increase awareness about the risk of death in using this drug.

Ropinirole involved in a fatal case: blood and urinary concentrations.

PURPOSE: Ropinirole is an antiparkinsonian  drug and has recently been suggested to be effective in amyotrophic lateral sclerosis. It is expected that ropinirole prescriptions will increase in the near future. However, the fatal concentration in blood is unclear at this time. Therefore, we report a fatal case involving ropinirole intoxication and discuss the fatal concentrations with reference to several autopsy cases involving ropinirole. METHODS: Ropinirole was quantified in femoral vein blood, cardiac blood, and urine from five autopsy cases in which ropinirole was detected by drug screening in our laboratory. One is a ropinirole intoxication case (this report) and the others  were non-intoxication cases. Their ropinirole concentrations were compared and discussed. RESULTS: The ropinirole concentration in this case was 100 ng/mL in femoral blood, 160 ng/mL in cardiac blood, and 1840 ng/mL in urine. The ropinirole concentrations in the four non-ropinirole poisoning cases were 7-35 ng/mL (mean: 24 ng/mL) in femoral blood, 13-100 ng/mL (mean: 60 ng/mL) in cardiac blood, and 140-1090 ng/mL (mean: 640 ng/mL) in urine. Cardiac/peripheral ratios were in the range of 1.6-2.1 (mean 1.8). CONCLUSIONS: There were no obvious signs of overdose, and the high cardiac/peripheral blood ratio suggested that postmortem redistribution may have occurred, but the  peripheral blood ropinirole concentration (100 ng/mL) was obviously higher than that reported in the previous fatal case of ropinirole poisoning (64 ng/mL). Based on these results, the cause of death in this case was considered to be shock and fatal arrhythmia due to ropinirole poisoning. This case provides important data on postmortem blood and urinary levels of ropinirole poisoning.

Evaluation of Post-Mortem Interaction between Hemoglobin and Oxime-Type Carbamate Pesticides.

Oxime-type carbamate pesticides having an oxime moiety such as aldicarb, butocarboxim, methomyl, oxamyl, and thiofanox are widely used and have been detected in many fatal cases of accidental exposure or suicide. In forensic toxicology, the accurate determination of blood pesticide concentration is obligatory to prove death by oxime-type carbamate pesticide poisoning. However, the fatal pesticide concentration in blood at autopsy differs from that at the time of death. In this study, we found that oxime-type carbamate pesticides were decomposed by Hb in a temperature-dependent fashion. The mechanism underlying methomyl, aldicarb, oxamyl, and thiofanox decomposition involves the formation of adducts with the amino acids in Hb. With regard to butocarboxim, its decomposition involves the oxidation of the free form and the formation of adducts with the amino acids in Hb. The mass spectra obtained by liquid chromatography quadrupole time-of-flight mass spectrometry revealed that carbamylated amino acid adducts such as Wcar-adduct and Vcar-adduct were formed in Hb solution incubated with methomyl, aldicarb, oxamyl, and thiofanox, whereas alkylated amino acid adducts such as Walkyl-adduct were formed in Hb solution incubated with butocarboxim. These results indicate that aldicarb, butocarboxim, methomyl, oxamyl, and thiofanox are post-mortem changed by Hb.

Post-mortem interaction between methidathion and human serum albumin in blood.

Methidathion [3-(dimethoxyphosphinothioylsulfanylmethyl)-5-methoxy-1,3,4-thiadiazol-2-one; hereinafter DMTP], one of the most widely used organophosphorus pesticides, has been detected in some clinical cases of accidental exposure and suicide in Japan. It has been reported that DMTP concentration is decreased in blood. In this study, it is difficult to recover DMTP in the free form because DMTP is bound to human serum albumin (HSA). We detected DMTP adducts in HSA by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q/TOF-MS). The mass spectra showed that DMTP was preferably bound to the lysine (K), tyrosine (Y), and cysteinylproline (CP) residues of HSA. The concentrations of K-adduct, DMTP-Y-adduct and DMTP-CP-adduct were increased in vitro in a dose-dependent fashion when DMTP concentration was lower than the lethal dose. Furthermore, the DMTP-Y-adduct and DMTP-CP-adduct were also detected in post-mortem blood of an autopsied subject who died by intentional DMTP ingestion. The results suggested that the DMTP-Y-adduct and DMTP-CP-adduct could be used as a biomarker of DMTP poisoning, and the decrease concentration of DMTP in blood after death could be determined on the basis of the concentration of the DMTP-CP-adduct in blood.

SmartAmp method can rapidly detect SARS-CoV-2 in dead bodies.

Rapid and accurate detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in dead bodies is essential to prevent infection among those working with dead bodies. This study focused on the Smart Amplification (SmartAmp) method, which has a short examination time (approximately an hour), is simple to perform, and demonstrates high specificity and sensitivity. This method has already been used for clinical specimens; however, its effectiveness in dead bodies has not been reported. This study examined the SmartAmp method using 11 autopsies or postmortem needle biopsies performed from January to May, 2021 (of these, five cases tested positive for SARS-CoV-2 by quantitative real-time polymerase chain reaction (qRT-PCR) and six cases tested negative). Swab samples were collected from the nasopharynx, oropharynx, or anus and the SmartAmp and qRT-PCR results were compared. For the nasopharynx and oropharynx samples, the same results were obtained for both methods in all cases; however, for the anal swabs, there was one case that was positive according to qRT-PCR but negative according to the SmartAmp method. The SmartAmp method may therefore be less sensitive than qRT-PCR and results may differ in specimens with a low viral load, such as anal swabs. However, in the nasopharynx and oropharynx specimens, which are normally used for testing, the results were the same using each method, suggesting that the SmartAmp method is useful in dead bodies. In the future, the SmartAmp method may be applied not only during autopsies, but also in various situations where dead bodies are handled.

Generation of disease-specific and CRISPR/Cas9-mediated gene-corrected iPS cells from a patient with adult progeria Werner syndrome.

Adult progeria Werner syndrome (WS), a rare autosomal recessive disorder, is characterized by accelerated aging symptoms after puberty. The causative gene, WRN, is a member of the RecQ DNA helicase family and is predominantly involved in DNA replication, repair, and telomere maintenance. Here, we report the generation of iPS cells from a patient with WS and correction of the WRN gene by the CRISPR/Cas9-mediated method. These iPSC lines would be a valuable resource for deciphering the pathogenesis of WS.

Association between sexual activity-related death and non-prescription use of phosphodiesterase type 5 inhibitors.

In recent years, there has been an increase in the use of phosphodiesterase type 5 inhibitors (PDE5i) that are purchased from abroad without a doctor's diagnosis via the Internet or other means. We report six cases in which nonprescription use of PDE5i may have led to death. Among the four deceased individuals who were believed to have experienced sudden cardiac death, three (cases 1-3) had a history of cardiovascular disease, which is a contraindication, and the remaining case (case 4) involved combined use of multiple PDE5i. Sildenafil (0.063 µg/mL, 0.087 µg/mL) was detected in two of the four cases of sudden cardiac death. Tadalafil (0.096 µg/mL) was detected in one of the remaining two cases, and tadalafil (0.197 µg/mL) and vardenafil (0.011 µg/mL) were detected in the other case. Sildenafil (0.032 µg/mL), tadalafil (0.062 µg/mL), and ethanol were detected in a traffic accident case with a history of contraindications. In a case of asphyxiation by vomit aspiration, autopsy showed 90% stenosis in the anterior descending branch of the coronary artery, and sildenafil (0.063 µg/mL) was detected. To the best of our knowledge, this is the first report of postmortem blood levels of tadalafil and vardenafil likely contributing to the cause of death. Despite all the warnings about the dangers of using PDE5 inhibitors, cases of PDE5i contributing to death are still identified during autopsies. Therefore, raising public awareness of the risks of the risks associated with the imported drug use by individuals is necessary.

The composition of chlorinated or oxidized phosphatidylcholine products changes with hypochlorite concentration: Application to abscess lipid analysis.

Hypochlorous acid, produced by myeloperoxidase upon neutrophil activation, can oxidize various compounds and exert antimicrobial activity in vivo. To elucidate the mechanisms underlying the reactions of the unsaturated phosphatidylcholines, which abound in cell membranes, with hypochlorous acid, we identified and examined phosphatidylcholine chlorination and oxidation products formed under various reaction conditions. We first investigated the products of unsaturated phosphatidylcholine and hypochlorous acid reaction with respect to hypochlorite concentration and reaction time. Next, we examined the lipids extracted postmortem from human abscesses. For all the analyses, we used liquid chromatography-quadrupole time-of-flight mass spectrometry. Various compounds, including phosphatidylcholine chlorohydrin and phosphatidylcholine hydroxide/epoxide, were detected. Oxidized phosphatidylcholines were mainly detectable upon reaction with low concentrations of sodium hypochlorite, whereas chlorinated phosphatidylcholines formed in the presence of higher concentrations. In human abscesses, oxidized phosphatidylcholines were detected in the cases with high procalcitonin concentration, whereas chlorinated phosphatidylcholines were undetected. The detections of oxidized phosphatidylcholines in human tissues might indicate previous exposure to hypochlorous acid in septic cases. Our results provide insight into the mechanisms underlying pathogen survival following inflammation associated with neutrophil activation and topical myeloperoxidase release and show postmortem biomarkers candidates for sepsis.

Sex estimation based on femoral measurements using multidetector computed tomography in cadavers in modern Japan.

We aimed to reproduce the anthropometrical measurements of femoral dimensions using multi-planar reconstruction (MPR) computed tomography (CT); to assess the feasibility of sex estimation using femoral measurements through this approach, and to establish the corresponding sex estimation thresholds in the modern Japanese population. We used data on 224 cadavers (116 male and 108 female) that were subjected to postmortem CT and subsequent forensic autopsy at our department between October 2009 and July 2016. Four femoral measurements were obtained. Receiver operating characteristic (ROC) curve analysis was performed to test the overall ability of the variables in sex estimation, while the accuracy of the sex estimation was measured by the area under the ROC curve (AUC). The femoral bicondylar breadth showed the largest AUC values (left; 0.973, right; 0.974), followed by the maximum head diameter (left; 0.951, right; 0.955), and maximum femoral length (left; 0.885, right; 0.887). To the best of our knowledge, this is the first report to assess sex estimation based on femoral measurements, using MPR CT images.

Relationship between KCNQ1 (LQT1) and KCNH2 (LQT2) gene mutations and sudden death during illegal drug use.

Long QT syndrome (LQTS), a congenital genetic disorder, can cause torsades de pointes (TdP), and lethal cardiac arrhythmia may result from ingestion of cardiotoxic drugs. Methamphetamine (MP) and new psychoactive substances (NPSs) can trigger TdP due to QT prolongation, leading to sudden death. We therefore analysed variations in the LQTS-associated genes KCNQ1 (LQT1) and KCNH2 (LQT2) using cardiac blood and myocardial tissue from subjects having died suddenly during MP or NPS use to investigate the relationship between congenital genetic abnormalities and sudden death during illegal drug use. We amplified and sequenced all exons of these genes using samples from 20 subjects, half of whom had died taking MP and half after using NPSs. G643S, a KCNQ1 missense polymorphism, was significantly more common among sudden deaths involving NPSs (6 subjects) than those involving MP (1 subject) and healthy Japanese subjects (P = 0.001). Notably, synthetic cathinones were detected in 2 of 3 cases involving G643S carriers. Previous functional analyses have indicated that the G643S polymorphism in the KCNQ1 potassium channel gene causes mild IKs channel dysfunction. Our data suggest that use of NPSs, particularly synthetic cathinones, is associated with elevated risk of serious cardiac arrhythmia and sudden death for subjects carrying KCNQ1 G643S.