A novel method for cyanide quantification in human whole blood using ion chromatography with amperometric detection and its application to cyanide intoxication cases

Cyanide is a highly toxic agent that has been frequently used for suicide in South Korea. It is also used in various industrial fields, such as metal plating, in which many accidental cyanide intoxications have occurred. To overcome the disadvantages of conventional cyanide analysis methods, a simple and fast method for the analysis of cyanide in whole blood using ion chromatography (IC) with amperometric detection was developed in this study. Whole blood samples were deproteinized, diluted, and analyzed using an IC–amperometric detection system. The limits of detection and quantitation were 0.1 and 0.2 mg/L, respectively. The method showed good linearity in the range of 0.2 to 50 mg/L with R² > 0.99. The intra- and inter-assay precision and accuracy values were <10%. The established method was successfully applied to analyze whole blood samples from three cyanide intoxication cases.     

Postmortem Computed Tomography in Firearm Homicides: A Retrospective Case Series,

Postmortem computed tomography (PMCT) is integrated into the evaluation of decedents in several American medical examiner offices and medicolegal death investigative centers in many other countries. We retrospectively investigated the value of PMCT in a series of firearm homicide cases from a statewide centralized medical examiner’s office that occurred during 2016. Autopsies were performed or supervised by board-certified forensic pathologists who reviewed the PMCT scans prior to autopsy. PMCT scans were re-evaluated by a forensic radiologist blinded to the autopsy findings and scored by body region (head–neck, thoracoabdominal, and extremities). Injury discrepancies were scored using a modified Goldman classification and analyzed with McNemar’s test. We included 60 males and 20 females (median age 31 years, range 3–73). Based on PMCT, 56 (79.1%) cases had injuries relevant to the cause of death in a single body region (24 head–neck region, 32 thoracoabdominal region). Out of these 56 cases, 9 had a missed major diagnosis by PMCT outside that region, including 6 extremity injuries visible during standard external examination. Yet all had evident lethal firearm injury. We showed that PMCT identifies major firearm injuries in homicide victims and excludes injuries related to the cause of death in other regions when a single body region is injured. Although PMCT has a known limited sensitivity for soft tissue and vascular pathology, it can be combined with external examination to potentially reduce or focus dissections in some of these cases depending on the circumstances and medicolegal needs.     

The Stability of 4-Chloromethcathinone in Blood and Vitreous Humor

We present results of our study on the stability of 4-chloromethcathinone (4-CMC) in authentic postmortem peripheral blood and vitreous humor samples. The stability of 4-CMC was determined in postmortem blood samples (for a period of 90 days) and vitreous humor (30 days) at three different temperatures: −15°C, +4°C, and + 23°C. The analyses were carried out using ultra-high-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS). In both materials, the lowest 4-CMC stability was demonstrated at room temperature. The blood samples stored in a freezer (−15°C) showed stability for the entire study period (90 days), while in the case of the vitreous humor sample stored at the same temperature the concentration of the substance decreased by 53% after 30 days. The study carried out in authentic postmortem blood and vitreous humor samples confirms the previous reports of 4-CMC instability in biological material. Authors suggest that the biological material should be stored frozen until analyses are carried out as soon as possible after collection of the material.     

骨折鉴定中MSCT及图像后处理的诊断与应用

目的探讨多层螺旋CT(MSCT)及其图像后处理功能在骨折法医鉴定中的诊断与应用价值。方法对366例法医鉴定者行薄层扫描并进行表面遮盖成像(SSD),透明化X线模拟投影(see-through)和多平面重建(MPR)处理。对所得图像进行诊断和分型。结果准确诊断并对134例鼻骨、98例眼眶和21例颅骨骨折进行分型。正确显示36例肋骨骨折、4例肩胛骨骨折、24例脊柱骨折和27例四肢骨及关节骨折。利用透明化X线模拟投影等技术鉴别陈旧性骨折18例。结论MSCT及图像后处理在骨折法医鉴定中具有重要实用价值,可为伤害等级鉴定提供有力的法医学依据。     

不同年龄组颅脑损伤CT扫描分析

本文对520例不同年龄组的颅脑损伤CT片进行了观察分析，表明青少年损伤原因以高坠多见，损伤类型以颅骨凹陷骨折及硬膜外血肿多见，老年组损伤原因以头部击伤多见，损伤类型以颅骨骨折、硬膜下血肿、脑多发性挫裂伤及脑多发性血肿多见，成年组介于两者之间。     

鼻骨骨折螺旋CT3D成像与X线片对比研究

目的 评价螺旋CT扫描三维重建成像与X线摄片对比对鼻骨骨折法医学鉴定的价值。方法 使用SOMATOM BALANCE 1s螺旋CT机，对32例复杂鼻部外伤者2mm／2mm扫描，常规进行最大密度投影法(MIP)、多平面重建(MPR)、表面覆盖法(SSD)、容积成像(VR)方式。全貌显示受伤鼻骨骨折影像，并与常规鼻骨摄片比较。结果 螺旋CT三维成像纠正3例X线照片的假阳性和6例诊断骨折类型不准确。结论 螺旋CT三维重建对诊断复杂鼻骨骨折块数目、移位，以及骨折类型优于X线摄片。     

甲维盐中毒死亡小鼠体内的分布及死后再分布

目的研究甲氨基阿维菌素苯甲酸盐(简称甲维盐)中毒死亡小鼠的致死血浓度、靶器官组织、毒物蓄积库和死后毒物再分布的特征。方法采用灌胃法建立中毒小鼠模型,动态观察急性中毒组、亚急性中毒组小鼠的主要中毒症状和临床死亡时间。观察中毒死后小鼠各器官组织病理形态学改变,应用酶联免疫吸附试验测定死后0、24、48、72h甲维盐体内分布及死后再分布,采用高效液相色谱法测定中毒小鼠的致死血浓度和死后各时间点的血中甲维盐浓度。结果中毒小鼠均在灌胃后15~30 min内依次出现神经、呼吸系统症状。急性中毒组小鼠的临床死亡时间为(45.8±7.9)min,亚急性中毒组为(8.0±1.4)d。甲维盐的急性致死血浓度范围为447.164 0~524.463 5 mg/L。光镜及荧光显微镜下各器官组织均见明显的病理改变;小鼠中毒死后72 h内,血、心、肝、脾、肺、肾及脑甲维盐浓度变化具有规律性(P0.05)。结论甲维盐中毒作用的主要靶器官为心、肝、肾、肺、脑和接触部位(胃),其主要蓄积库为肾、肝,甲维盐在小鼠体内存在死后再分布现象。     

死后眼组织变化与死亡时间推断

眼组织推断死亡时间一直是国内外法医学界的研究热点之一,从肉眼观到镜下观,从细胞水平到分子水平,不断有新的研究成果和报告出现。大量研究资料表明,随着死亡时间的延长,眼角膜、视网膜、玻璃体液及房水等均出现规律性的变化,并与死亡时间高度相关,可用于死亡时间推断。本文对其在法医学领域的研究进展作以综述。     

Unusual and Fatal Case of an Undiagnosed Intravascular Large B-cell Lymphoma: The Oncologist’s Great Imitator†

Intravascular lymphoma (IVL) is a rare subtype of extranodal lymphomas that is characterized by the selective growth of neoplastic cells within the lumen of small vessels. Authors document the case of an unexpected death caused by an undiagnosed intravascular large B-cell lymphoma with multi-organ involvement, which had initially manifested as an infection and then as an unclarified central nervous system pathology. Histological examination showed a diffuse intravascular large B-cell brain lymphoma with prominent cerebral involvement. The relevance of the case report reveals the importance of an autopsy of an extremely rare and threatening pathology that in most cases is diagnosed only postmortem. As a result, the role of the forensic pathologist becomes particularly important. When specifically performing an in-depth autopsy evaluation with a specific histologic analysis, it is possible to identify the intravascular lymphoma and declare a more accurate cause of death.     

根据颈椎CT片特征指标进行同一认定的研究

目的选择颈椎CT片上的特征指标,建立逐步回归方程,探讨其在法医学同一认定中的应用价值。方法收集130名被检查者颈椎CT片各1张,70名被检查者不同次颈椎CT影像片各2张。选择并测量颈椎CT片上的13项指标值,分别计算被检查者随机分组后相同测量指标的组间差值,以及同一人不同次测量指标间的差值,运用二分类logistic逐步回归分析,建立各项指标的一元回归方程和多项指标的多元回归方程,并对方程进行盲测检验。结果建立的13个一元方程中同一认定的准确率在69.0%~90.4%之间;建立的4个多元回归方程的准确率在90.4%~96.7%之间,盲测准确率为100%。结论本文在CT片上选择的13项特征指标可以用于同一认定,使用时应尽可能选用多元指标以得到更准确的结果。