Assessment of a Sudden Death Case due to Coronary Artery Disease Based on the PMCT and Forensic Autopsy

It is never an easy thing to diagnose heart vascular disease only depending on the unenhanced postmortem computed tomography(PMCT).This article reported a case of sudden natural death after the complaint of anterior chest pain in which coronary artery calcification(CAC) was clearly displayed using PMCT scan.The entire coronary artery system was almost reconstructed via multiplanar reformation(MPR) and volume-rendering reconstruction(VR),and the total calcium score of the coronary arteries was obtained with CaScoring automatic analysis software.The results showed that CAC was conspicuous;the total calcium score was 640.3,considerably higher than 400.The pulmonary ground-glass opacity(GGO) and small amount of fluid both in the subglottic trachea and main bronchi were also found.The imaging results confirmed those of autopsy.In addition,the results concluded that PMCT might serve as an invaluable adjunct to the classic autopsy procedure.

Messenger RNA Profiling for Forensic Body Fluid Identification： Research and Applications

Identifying the origin of body fluids left at a crime scene can give a significant insight into crime scene reconstruction by supporting a link between sample donors and actual criminal acts.However,the conventional body fluid identification methods are prone to various limitations,such as time consumption,intensive labor,nonparallel manner,varying degrees of sensitivity and limited specificity.Recently,the analysis of cell-specific messenger RNA expression(mRNA profiling)has been proposed to supplant conventional methods for body fluid identification.Since 2011,the collaborative exercises have been organized by the European DNA Profiling Group(EDNAP)in order to evaluate the robustness and reproducibility of mRNA profiling for body fluid identification.The major advantages of mRNA profiling,compared to the conventional methods,include higher sensitivity,greater specificity,the ability of detecting several body fluids in one multiplex reaction,and compatibility with current DNA extraction and analysis procedure.In the current review,we provided an overview of the present knowledge and detection methodologies of mRNA profiling for forensic body fluid identification and discussed its possible practical application to forensic casework.

Cognitive control subprocess deficits and compensatory modulation mechanisms in patients with frontal lobe injury revealed by EEG markers:a basic study to guide brain stimulation

Background Frontal lobe injury(FLI)is related to cognitive control impairments,but the influences of FLI on the internal subprocesses of cognitive control remain unclear.Aims We sought to identify specific biomarkers for long-term dysfunction or compensatory modulation in different cognitive control subprocesses.Methods A retrospective case-control study was conducted.Event-related potentials(ERP),oscillations and functional connectivity were used to analyse electroencephalography(EEG)data from 12 patients with unilateral frontal lobe injury(UFLI),12 patients with bilateral frontal lobe injury(BFLI)and 26 healthy controls(HCs)during a Go/NoGo task,which included several subprocesses:perceptual processing,anticipatory preparation,conflict monitoring and response decision.Results Compared with the HC group,N2(the second negative peak in the averaged ERP waveform)latency,and frontal and parietal oscillations were decreased only in the BFLI group,whereas P3(the third positive peak in the averaged ERP waveform)amplitudes and sensorimotor oscillations were decreased in both patient groups.The functional connectivity of the four subprocesses was as follows:alpha connections of posterior networks in the BFLI group were lower than in the HC and UFLI groups,and these alpha connections were negatively correlated with neuropsychological tests.Theta connections of the dorsal frontoparietal network in the bilateral hemispheres of the BFLI group were lower than in the HC and UFLI groups,and these connections in the uninjured hemisphere of the UFLI group were higher than in the HC group,which were negatively correlated with behavioural performances.Delta and theta connections of the midfrontal-related networks in the BFLI group were lower than in the HC group.Theta across-network connections in the HC group were higher than in the BFLI group but lower than in the UFLI group.Conclusions The enhancement of low-frequency connections reflects compensatory mechanisms.In contrast,alpha connections are the opposite,therefore revealing more abnormal neural activity and less compensatory connectivity as the severity of injury increases.The nodes of the above networks may serve as stimulating targets for early treatment to restore corresponding functions.EEG biomarkers can measure neuromodulation effects in heterogeneous patients.

An Anatomical and Radiological Study of Origins of the Arteries Forming the Celiac Trunk: Clinical and Embryological Implications

The blood supply to the most of abdominal organs is provided by the branches of CT. The SMA supply caecum, ascends colon, all of the small bowels except the upper part of duodenum. Knowledge of variable anatomy of celiac axis and SMA may be useful in planning and executing radiological interventions such as celiacography and chemoembolization of hepatic and pancreatic tumors. In this study, the uncommon or low percentage cases of CT and SMA are presented in the light of clinical and embryological information. The celiac axises of a total of 30 adult corpses were examined. Dissections of abdominal region were performed in detail according to Cunningham’s manual. Angiographic images of 100 consecutive adult patients who underwent celiac MDCT angiography were evaluated. During autopsies, an incomplete celiac trunk or bifurcation of celiac trunk associated with the hepatomesenteric and gastrosplenic trunks (0.7%) and a celiacomesenteric trunk associated with high origin superior mesenteric artery and gastrosplenic trunk were detected (0.7%). During MDCT angiography, a case of total absence of celiac trunk associated with a hepatosplenomesenteric trunk (0.7%) and also a case of total absence of celiac trunk alone were observed (0.7%). The persistence or unusual development of ventral splanchnic arteries (VSAs) or ventral longitudinal anastomosis may result in variations or the unusual trunks related to celiac axis and SMA. The anomalous trunks of the CT may be result of either the persistence of some parts of the VSAs or ventral longitudinal anastomose that normally disappear or disappearance of parts that normally persist. The prevalence of unusual trunks of celiac axis and SMA in this study is quite low in literature. These abnormal vessels pose problems for surgeons and radiologists. Such vascular anomalies may cause clinical complications following surgical and radiological procedures such as resection of tumor of the pancreatic head, lymphadenectomy, coeliacography, aortic replacement with reimplantation of the trunk and coembolization of pancreatic and liver tumors.

Reliability Study on Quantitative Detection of Extensor Digi- torum Brevis Strength with Needle Electromyography and Nerve Conduction

Objective To study the objectivity and reliability of needle electromyography and nerve conduction for detection of musculus extensor digitorum brevis strength, which may provide a basis for establishing a quantitative detection of muscle strength in forensic clinical study. Methods Forty-four healthy people were enrolled as the subjects, and during toe dorsiflexion, the following items including needle electromyography indexes, motor unit potential(MUP) amplitude, MUP count, recruitment reaction type, and nerve conduction detection indexes, compound muscle action potential(CMAP) amplitude, CMAP latent period and motor nerve conduction velocity(MNCV), were simultaneously detected under the cooperation and disguise condition. Results Under the cooperation condition, regardless of the same operator or different operators, there were good test-retest reliabilities in MUP amplitude, CMAP amplitude, CMAP latent period and MNCV, while there were normal test-retest reliabilities in MUP count and recruitment reaction type and the repeatability of the same operator was slightly better than the repeatability between different operators. Under the disguise condition, test-retest reliabilities of MUP amplitude, CMAP amplitude, CMAP latent period and MNCV were relatively high, while test-retest reliabilities of MUP count and recruitment reaction type were relatively low. Conclusion There are good test-retest reliabilities in MUP amplitude, CMAP amplitude, CMAP latent period and MNCV, which can be conducive to comparison between different operators and results at various times; MUP count and recruitment reaction type, which can be easily affected by subjectivity of operators and examinees, can be used to differentiate whether an examinee disguises or not. The indexes used to objectively judge muscle strength remain to be further investigated.

Severe Hypokalemia due to Combination Use of Dexamethasone and Calcium Gluconate for Diabetics with Infection： A Case Report

The combination use of dexamethasone and calcium gluconate can be applied to hypersensitivity. Severe hypokalemia is a usual complication of dexamethasone and calcium gluconate therapy, which occurs frequently with therapeutic use. Fatal cases, accidental and intentional, occur frequently in forensic practice. The current case report presented a 43-year-old man with diabetes mellitus with infection, to whom dexamethasone and calcium gluconate were administered in the private clinic. With the development of such clinical symptoms of severe hypokalemia as quadriplegia, he was confirmed to have severe hypokalemia through a biochemical test before dying of arrhythmia. And also it presented pathophysiologic mechanism underlying severe hypokalemia as well as suggestions for clinical practice regarding combination use of dexamethasone and calcium gluconate.

Simultaneous Screening for 45 Poisonous Alkaloids in Blood by LC-MS/MS

Objective To develop a liquid chromatography-tandem mass spectrometry(LC-MS/MS) screening method for 45 poisonous alkaloids in blood. Methods Identification was based on the compound's retention time and two precursor-to-production transitions. The method involved a liquid-liquid extraction(LLE) followed by LC-MS/MS with multiple-reaction monitoring(MRM). When 1 m L of blood was extracted with diethyl ether at p H=9.2 with SKF525 Aas the internal standard, the target compounds were analyzed with LC-MS/MS in the positive ionization mode. Results The target alkaloids had good linearity(r>0.995 1), both the intra-day precision and inter-day precision being less than 14.77%. The limits of detection ranged from 0.05 to 25 ng/m L in blood. Conclusion The method is selective and sensitive in detecting poisonous alkaloids with a total running time of 12 minutes; therefore it was successfully applied to some actual cases of suspected alkaloids poisoning.

Numerical Reconstruction and Injury Biomechanism in a Car- Pedestrian Crash Accident

Objective To reconstruct a car-pedestrian crash accident using numerical simulation technology and explore the injury biomechanism as forensic evidence for injury identification. Methods An integration of multi-body dynamic, finite element (FE), and classical method was applied to a car-pedestrian crash accident. The location of the collision and the details of the traffic accident were determined by vehicle trace verification and autopsy. The accident reconstruction was performed by coupling the three-dimensional car behavior from PC-CRASH with a MADYMO dummy model. The collision FE models of head and leg, developed from CT scans of human remains, were loaded with calculated dummy collision parameters. The data of the impact biomechanical responses were extracted in terms of von Mises stress, relative displacement, strain and stress fringes. Results The accident reconstruction results were identical with the examined ones and the biomechanism of head and leg injuries, illustrated through the FE methods, were consistent with the classical injury theories. Conclusion The numerical simulation technology is proved to be effective in identifying traffic accidents and exploring of injury biomechanism.

Electroretinogram and Histopathologic Changes of the Retina after Methanol Intoxication

In order to study the functional and structural alterations of the retina in SD rat model after methanol intoxication,35 rats were divided randomly into five groups administrated with saline,3-day high dose,7-day high dose,3-day low dose and 7-day low dose methanol separately.The retinal function of each group was assessed by flash electroretinogram(F-ERG) 3 and 7 days after methanol poisoning.The microstructure and ultrastructure of the retina were observed at the same time.The high-dose methanol intoxication induced irreversible retinal functional and structural damages 3 days after poisoning,which included prolonged latency and reduced amplitude of the Max-reaction of F-ERG.These injuries were aggravated 7 days after poisoning.Meanwhile,the latency and amplitude of the Cone-reaction of F-ERG were also affected 3 days after poisoning,but there were no further worsening tendency 7 days after poisoning.The retinal histological analysis showed cellular edema,heteromorphy and disarrangement,tissular loosen of the inner nuclear layer and photoreceptors layer.The mitochondrial damage began at the photoreceptors layer and developed further into the inner nuclear layer.The low-dose methanol intoxication only caused transient damage of the retina.Our results showed that the function and structure of the photoreceptor and inner nuclear layer were the primary target of methanol intoxication and that the rod cells were more sensitive to methanol intoxication than the cone cells.The mitochondrial damage developed from outer layer to inner layer of the retina.

Stature Estimation Based on the Length of Tibia and Fibula Measured by Digital X-ray in Chinese Han Teenagers

Objective To derive regression formulae for stature estimation using forensic radiography from the tibia and fibula of Chinese Han teenagers in Sichuan Province. Methods To construct equations, measurements were conducted on the training sample (412 adults, 201 males and 211 females). The whole length of the fibula and four measurements of tibia were determined using CR radiography, rectified through theoretical magnification. The regression formulae were relatively constructed to the real stature measured in an erect position. Through using the testing sample (40 adults) for the regression formulae, the reliability of the regression formulae was assessed. Results The range of correlation coefficients of four measurements for tibia was 0.880-0.895 in the sex-unknown group, 0.869-0.893 in the male, and 0.8450.855 in the female. The five measurements were found to be better correlated with stature in the male than in the female. Conclusion The digital X-ray of the tibia and fibula for stature estimation is proved to be effective in forensic individual identification; therefore, these equations can be of great assistance to the stature estimation of the contemporary Chinese Han teenagers.

Long-Term Trend of Bone Development in the Contemporary Teenagers of Chinese Han Nationality

Objective To further improve the accuracy of bone age identification using the time of secondary ossification center appearance and epiphyseal fusion of 7 joints to estimate the age of living individuals.Methods DR films were taken from 7 parts including sternal end of clavical and the left side of shoulder,elbow,carpal,hip,knee and ankle joints of 1 709 individuals who came from eastern China,central China and southern China,whose ages were between 11.0 and 20.0 years.From those 7 joints 24 osteal loci were selected as bone age indexes,which could better reflect age growth of teenagers.The characteristics of secondary ossification center appearance and epiphyseal fusion were observed,and the mean and age range of secondary ossification center appearance and epiphyseal fusion were calculated.Results The fusion time of the 24 epiphyses were advanced at different degrees,the most obvious epiphyses the sternal end of clavicle,scapular acromial end,distal end of the radius,distal end of the ulna,iliac crest,ischial tuberosity,the upper and lower end of tibia and fibula.The appearance time of sternal end of clavicle,scapular acromial end,iliac crest and ischial tuberosity epiphyses were all found to be after the age of 12,and the female's age,approximately 1 year ahead of schedule in comparison with the male's.Conclusion The relevant forensic information and data for bone age identification should be updated every 10-15 years so as to provide accurate and objective evidence for court testimony,conviction and sentencing.

Postmortem MSCT Diagnosis of Whiplash Injuries in a Traffic Accident：A Case Report and Review of the Literature

A 45-year-old male car driver died in a traffic accident of four cars rear-end collision on the highway.He was found to have died after a respiratory and cardiac arrest at the scene.No sign of skin injuries was observed from the external inspection.The autopsy was not permitted by the family members because of the local culture.Multislice computed tomography(MSCT)was applied to the current case,showing dislocation of C3~4cervical vertebrae withⅡdegree,C4vertebral plate fractures,and spinal stenosis.Post-mortem MSCT confirmed the diagnosis as whiplash injuries.MSCT was verified to be effective in showing the severity of whiplash injuries,thus providing certain objective evidence for medicolegal expertise.

3D Finite Element Model of Human Knee Injuries in the Traffic Accident

Objective To explore the injury mechanism of the human knee in a traffic accident by establishing a 3D finite element(FE) model. Methods The FE model, composed of femur, tibia, fibula, patella, meniscus, knee ligaments and surrounding soft tissues, was reconstructed by CT scanning data from a male volunteer. Validation was performed by the lateral impact simulation, and the stress and strain results were obtained to be compared with those previously reported for injury prediction. Results The results derived from the FE model were found to be similar with those previously reported, most of the ligaments and meniscus wounded at 40 m/s collision, which was readily observed. Conclusion The simulation results generated by FE model can be effectively used for the injury mechanism analysis of initial contact.

Mathematical Models for Teenager's Living Age Evaluation Based on CT Image of Medial Clavicular Epiphysis

Objective To explore the correlation between volume rendering(VR) statistics of medial clavicular epiphysis and living age,and establish the mathematical models for living age evaluation using the CT image of medial clavicular epiphysis based on the growth rules of osteoepiphysis of medial clavicle.Methods The CT images of the medial clavicles from 795 teenagers aged 15-25,387 males and 408 females,were collected in East and South China.VR 3D images were reconstructed from 0.60 mm-thick slice CT images.The epiphyseal diameter,sternal end diameter,and their respective diameter ratio(the left: x 1;the right: x 3);epiphyseal area,sternal end area,and their respective area ratio(the left: x 2;the right: x 4),were measured and calculated.All these observations were analyzed using SPSS 19.0 statistical software.The statistical differences in gender and age were analyzed by Mann-Whitney U test.The mathematical models were established using least square.Sixty trained subjects,30 males and 30 females,were tested to verify the accuracy of the established mathematical models.Results In the group of same age,x 1 showed significant difference in gender;the same results were observed in x 2,x 3,and x 4,which suggested that the growth rules of osteoepiphysis of medial clavicle were highly correlated with living age.The accuracy of these mathematical models were all above 67.6%(±1.0 year) and 78.5%(±1.5 year).Conclusion The mathematical models with reasonable accuracy could be manageable in practice to confirm the conclusion of the atlas method.The current study can contribute to the single skeletal age evaluation.

Quality Control System of Judicial Expertise in China

The current quality control system of judicial expertise in China For a long time in China,the administrative organization of justice has been subordinate to universities,Ministry of Public Health,Ministry of Public Security,the Procuratorate,the Court and National Security Agency.These administrative organizations are mainly in charge of the management of judicial expertise.The quality control system of judicial expertise can be classified into three levels.

Fatal Acute Compartment Syndrome Following a Falling Injury： A Case Report

Acute compartment syndrome （ACS） usually occurs after an injury to a limb or other adjacent organ, when there is insufficient blood supply to muscles and nerves due to swelling and increased pressure within a body compartment. Classically, there are six symptoms and signs associated with ACS, all of which have an initial letter ＇P＇： pain, paresthesia, pallor, paralysis, pulselessness and poik- ilothermia The complexities of the clinical diag- nosis and management of ACS remain a challeng- ing oroblem for orthooedic surgeons.

Method Development and Validation for Determining 1,3-Bu- tadiene in Human Blood by Gas Chromatography-Mass Spec- trometry and Head-Space Gas Chromatography

To develop a simple,validated method for identifying and quantifying 1,3-butadiene(BD) in human blood by gas chromatography-mass spectrometry(GC-MS) and head-space gas chromatography(HS-GC).BD was identified by GC-MS and HS-GC,and quantified by HS-GC.The method showed that BD had a good linearity from 50 to 500μg/mL(r>0.99).The limits of detection and quantification were 10 μg/mL and 50 μg/mL,respectively.Both the intra-day precision and inter-day precision were <6.08%,and the accuracy was 96.98%-103.81%.The method was applied to an actual case,and the concentration of BD in the case was 242 μg/mL in human blood.This simple method is found to be useful for the routine forensic analysis of acute exposure to BD.

Progress of DNA-based Methods for Species Identification

Species identification of biological samples is widely used in such fields as forensic science and food industry. A variety of accurate and reliable methods have been developed in recent years. The current review shows common target genes and screening criteria suitable for species identification, and described various DNA-based molecular biology methods about species identification. Additionally, it discusses the future development of species identification combined with real-time PCR and sequencing technologies.