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A 25-year-old, emaciated man without medical treatment was found to have died suddenly at home by his mother. At autopsy, there were no injuries to his body, but significant circulatory insufficiency was observed. Electron microscopy revealed abnormal mitochondria in cells of the cardiac conduction system. The conduction system was filled with mitochondrial size abnormalities and mitochondrial cristae abnormalities. No notable abnormal findings were observed in other organs. Genetic examination of the blood revealed the mitochondrial pathogenetic variant m.3243A>G. Epileptic seizures, diabetic ketoacidosis, and hyperosmolar hyperglycemic state were unlikely to be the cause of sudden death. The cause of death was diagnosed as arrhythmia possibly induced by the failure of the cardiac conduction system due to mitochondrial disease. This is a rare case of sudden death caused by an accumulation of abnormal mitochondria in the cardiac conduction system.  相似文献   
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《Clinical therapeutics》2022,44(12):1604-1623
PurposeVoriconazole, an antifungal drug, is metabolized by a cytochrome P450 isozyme. Increased adverse effects are observed in Asians because of the high rate of poor metabolizers. In this therapeutic drug monitoring (TDM) guideline, recommendations were made according to ethnic group.MethodsFive clinical questions were used. For the preparation of the guideline, the performance of TDM in multicenter studies was surveyed (study 1). We also conducted a systematic review and meta-analysis (study 2) to establish recommendations for non-Asians and Asians.FindingsIn study 1, 401 patients were surveyed. A risk of supratherapeutic concentrations was found in Japanese patients who adhered to the recommended dose. Target trough levels were achieved in 87% of patients with dose reductions. Although the trough level measured at the onset of adverse effects (AEs) was significantly associated with hepatotoxicity, no significant correlation was found between the initial trough level and hepatotoxicity, which indicated that hepatotoxicity was successfully prevented by the trough-guided dosing. In study 2, 22 studies (11 Asian locations and 11 non-Asian locations) were included in meta-analysis for the relationship between trough cutoff level (3, 4, 5, 5.5, and 6 µg/mL) and AEs. Significant differences were found for all cutoff levels, with the highest odds ratio for 4.0 µg/mL in Asian locations. In contrast, in non-Asian locations, no more than 1 study was available for any trough cutoff level, except for 5.5 µg/mL, at which level a significant increase in AEs was found. These findings indicate that TDM is strongly recommended to prevent AEs in Asians, and TDM is generally recommended for non-Asians to address subtherapeutic concentrations. TDM on day 3 is recommended to assess pharmacokinetic properties, including loading and maintenance doses. If the patient condition permits, delaying until day 5 is suggested for Asians because of the prolonged t½ in poor metabolizers. A trough level ≥1.0 µg/mL is strongly recommended to improve efficacy. Trough levels ≥2.0 µg/mL are suggested for invasive aspergillosis. To decrease adverse effects, trough levels <4.0 µg/mL are strongly recommended in Asians, whereas trough levels <5.5 µg/mL are generally recommended in non-Asians. Maintenance doses of 4 and 3 mg/kg twice daily are recommended in non-Asians and Asians, respectively.ImplicationsDifferent indications, timings, and target trough levels for TDM and different regimens are suggested for Asians and non-Asians.  相似文献   
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PurposeAccording to the social determinants of health framework, income inequality is a potential risk factor for adverse mental health. However, few studies have explored the mechanisms suspected to mediate this relationship. The current study addresses this gap through a mediation analysis to determine if social support and community engagement act as mediators linking neighbourhood income inequality to maternal anxiety and depressive symptoms within a cohort of new mothers living in the City of Calgary, Canada.MethodsData collected at three years postpartum from mothers belonging to the All Our Families (AOF) cohort were used in the current study. Maternal data were collected between 2012 and 2015 and linked to neighbourhood socioeconomic data from the 2006 Canadian Census. Income inequality was measured using Gini coefficients derived from 2006 after-tax census data. Generalized structural equation models were used to quantify the associations between income inequality and mental health symptoms, and to assess the potential direct and indirect mediating effects of maternal social support and community engagement.ResultsIncome inequality was not significantly associated with higher depressive symptoms (β = 0.32, 95%CI = −0.067, 0.70), anxiety symptoms (β = 0.11, 95%CI = −0.39, 0.60), or lower social support. Income inequality was not associated with community engagement. For the depression models, higher social support was significantly associated with lower depressive symptoms (β = −0.13, 95%CI = −0.15, −0.097), while community engagement was not significantly associated with depressive symptoms (β = 0.059, 95%CI = −0.15, 0.27). Similarly, for the anxiety models, lower anxiety symptoms were significantly associated with higher levels of social support (β = −0.17, 95%CI = −0.20, −0.13) but not with higher levels of community engagement (β = 0.14, 95%CI = −0.14, 0.41).ConclusionThe current study did not find clear evidence for social support or community engagement mediating the relationship between neighbourhood income inequality and maternal mental health. Future investigations should employ a broader longitudinal approach to capture changes in income inequality, potential mediators, and mental health symptomatology over time.  相似文献   
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In forensic medicine, although various alcohols have been reported as indicators of decomposition in collected blood, no studies have examined short-chain fatty acids as indicators. In this study, the blood n-butyric acid concentration was quantified, and the association between n-butyric acid and decomposition was investigated to determine whether the detection of n-butyric acid could be a new indicator of decomposition. Among the forensic autopsies performed from 2016 to 2018 in our laboratory, the cases were divided into decomposed (n = 20) and non-decomposed (n = 20) groups based on macroscopic findings. Blood samples collected at the time of autopsy were derivatized with 3-nitrophenylhydrazine hydrochloride after solid-phase extraction. The n-butyric acid concentration was measured using liquid chromatography–tandem mass spectrometry. In addition, ethanol and n-propanol were measured using a gas chromatography-flame ionization detector. There was a significant difference (p < 0.01) in the concentrations of n-butyric acid between the decomposed and non-decomposed groups (0.343 ± 0.259 [0.030–0.973] and 0.003 ± 0.002 [0.001–0.007] mg/mL, respectively). In the decomposed group, n-butyric acid was detected at high concentrations, even in cases where n-propanol was low. These results suggest that n-butyric acid is more likely to be an indicator of blood decomposition than n-propanol.  相似文献   
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BackgroundHamstring strain injuries are the most common type of injury in elite football and are associated with a high risk of reinjury, particularly those involving the intramuscular tendon (IMT). Limited information is available regarding the rehabilitation and return to sport (RTS) processes following such injuries. This case study describes the clinical presentation of an elite football player following IMT hamstring injury, their on- and off-pitch rehabilitation alongside performance monitoring throughout RTS and beyond.Case scenarioAn elite football player suffered a grade 2c hamstring injury during an English Premier League (EPL) match. The player underwent early post-injury management, alongside progressive off-pitch physical preparation. The ‘control-chaos continuum’ was used as a framework for on-pitch rehabilitation to prepare the player for a return to full team training and competition. Objective and subjective markers of the player's response to progressive on- and off-pitch loading were monitored throughout RTS and beyond.OutcomesThe player returned to on-pitch rehabilitation after 11 days, to full team training having achieved weekly pre-injury chronic running load outputs after 35 days and played in the EPL 40 days post-injury. The player did not suffer reinjury for the rest of the EPL season.ConclusionAn understanding the unique structural and mechanical properties of the IMT, alongside expected RTS timeframes are important to inform rehabilitation and decision-making processes post-injury. Performance and frequent load-response monitoring throughout RTS and beyond, in conjunction with practitioner experience and effective communication are critical in facilitating effective RTS and reduce risk of reinjury following IMT injury.  相似文献   
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