Application of Sphenoid Sinus Morphological Characteristics in Sex Estimation Based on Magnetic Resonance Imaging Images / Aplicación de las Características Morfológicas del Seno Esfenoidal en la Estimación del Sexo Basada en Imágenes de Resonancia Magnética

SUMMARY: Sex determination of unknown persons plays an important role in forensic science. As most bones used for sex determination are recovered in incomplete state, it is often necessary to use bones that are recovered intact e.g., the sphenoid sinus. This study aimed to evaluate the diagnostic value of sphenoid sinuses dimensions for sex determination using Magnetic Resonance Imaging (MRI) images in Chinese adults. MRI images of 79 sphenoid sinuses (from 44 men and 35 women) were retrospectively selected. The height, anterior-posterior diameter, area, and perimeter were measured in the midsagittal view of the sphenoid sinuses. All data were subjected to descriptive and discriminative functional analysis with unpaired t-test and canonical discriminant. Comparison between male and female groups showed significant statistical differences regarding the height, anterior-posterior diameter, area, and perimeter of sphenoid sinuses. The predictive accuracy rate of the sphenoid sinus to identify sex was 63.6 % in males and 62.9 % in females with an overall accuracy of 63.3 %. This study proposed the importance of sexual dimorphism of sphenoid sinus dimensions, especially if other methods are not available. It suggested using MRI in forensics science thus obviating the complete dependence on the usage of conventional computed tomography (CT) and facilitating the study of forensic anatomy at the level of soft tissue.

La determinación del sexo de personas desconocidas juega un papel importante en la ciencia forense. Como la mayoría de los huesos utilizados para la determinación del sexo se recuperan en un estado incompleto, a menudo es necesario utilizar huesos recuperados intactos, por ejemplo, el seno esfenoidal. Este estudio tuvo como objetivo evaluar el valor diagnóstico de las dimensiones de los senos esfenoidales para la determinación del sexo utilizando imágenes de resonancia magnética en individuos adultos chinos. Se seleccionaron retrospectivamente imágenes de resonancia magnética de 79 senos esfenoidales (de 44 hombres y 35 mujeres). La altura, el diámetro anteroposterior, el área y el perímetro de los senos esfenoidales, se midieron en vista mediana sagital. Todos los datos se sometieron a análisis funcional descriptivo y discriminativo con prueba t no pareada y discriminante canónico. La comparación entre los grupos de hombres y mujeres mostró diferencias estadísticas significativas en cuanto a la altura, el diámetro anteroposterior, el área y el perímetro de los senos esfenoidales. La tasa de precisión predictiva del seno esfenoidal para identificar el sexo fue del 63,6 % en hombres y del 62,9 % en mujeres, con una precisión general del 63,3 %. Este estudio propuso la importancia del dimorfismo sexual de las dimensiones del seno esfenoidal, especialmente si no se dispone de otros métodos. Se sugiere utilizar la resonancia magnética en la ciencia forense, obviando así la dependencia total del uso de la tomografía computarizada convencional y facilitando con esto el estudio de la anatomía forense a nivel de los tejidos blandos.

Exploration and Practice of the "One Combination, Two Highlights, Three Combinations, Four in One" Innovative Talents Training Mode in Forensic Medicine / 法医学杂志

Talent is one of the basic and strategic supports for building a modern socialist country in all aspects. Since the 1980s, the establishment of forensic medicine major and the cultivation of innovative talents in forensic medicine have become hot topics in higher education in forensic medicine. Over the past 43 years, the forensic medicine team of Shanxi Medical University has adhered to the joint education of public security and colleges, and made collaborative innovation, forming a training mode of "One Combination, Two Highlights, Three Combinations, Four in One" for innovative talents in forensic medicine. It has carried out "5+3/X" integrated reform, and formed a relatively complete talent training innovation mode and management system in teaching, scientific research, identification, major, discipline, team, platform and cultural construction. It has made a historic contribution to China's higher forensic education, accumulated valuable experience for the construction of first-class major and first-class discipline of forensic medicine, and provided strong support for the construction of the national new forensic talent training system. The popularization of this training mode is conducive to the rapid and sustainable development of forensic science, and provides more excellent forensic talents for national building, regional social development and the discipline construction of forensic science.

Detection of Carbamazepine and Its Metabolites in Blood Samples by LC-MS/MS / 法医学杂志

OBJECTIVES@#To establish a method for the detection of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS).@*METHODS@#The blood samples were treated with 1-butyl-3-methylimidazolium hexafluorophosphate as an extraction solvent. The samples were extracted by ultrasound-assisted extraction and separated by ZORBAX Eclipse Plus C18, 95Å column. The mobile phase A aqueous solution containing 0.1% formic acid and 10 mmol/L ammonium acetate, and mobile phase B mixed organic solvent containing acetonitrile/methanol (Vacetonitrile∶Vmethanol=2∶3) were used for gradient elution at the flow rate of 1.00 mL/min. An electrospray ion source in positive mode was used for detection in the multiple reaction monitoring.@*RESULTS@#The linearities of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples were good within the corresponding range, with correlation coefficients (r) greater than 0.995 6. The limits of detection were 3.00, 0.40 and 1.30 ng/mL, respectively. The limit of quantitation were 8.00, 1.00 and 5.00 ng/mL, respectively. The extraction recoveries ranged from 76.00% to 106.44%. The relative standard deviations of the intra-day and inter-day precisions were less than 16%. Carbamazepine and its main metabolite 10,11-dihydro-10,11-epoxycarbamazepine were detected in blood samples of death cases with a mass concentration of 2.71 μg/mL and 252.14 ng/mL, respectively.@*CONCLUSIONS@#This method has high sensitivity and good selectivity, which is suitable for the detection of carbamazepine and its metabolites in blood samples, and can be used for carbamazepine-related forensic identifications.

Postmortem Distribution and Postmortem Redistribution of Carbofuran-7-Phenyl Glucuronic Acid in Rabbits / 法医学杂志

OBJECTIVES@#To establish a carbofuran intragastric administration death model in rabbits, and to observe the postmortem distribution and postmortem redistribution of carbofuran-7-phenyl glucuronic acid (Glu-7PH) in rabbits.@*METHODS@#The postmortem distribution: Rabbits were given an administration of 1/2LD50, LD50, 2LD50 carbofuran. Dead rabbits were dissected immediately. Rabbits that had remained alive 2 hours were sacrificed by carbon dioxide (CO2) inhalation and dissected immediately. The myocardium, cardiac blood, liver, spleen, lung, kidney, brain and right hindlimb muscle were collected. The postmortem redistribution: After giving an administration of 4LD50 carbofuran, the myocardium, cardiac blood, liver, spleen, lung, kidney, brain, and right hindlimb muscle were collected at 0, 12, 24, 48, and 72 h postmortem in supine position at 15 ℃ room temperature. The quantity of Glu-7PH was determined by LC-MS/MS.@*RESULTS@#The postmortem distribution: Among the three dose groups, there were significant differences in the quantities of Glu-7PH in different tissues. The postmortem redistribution: There was no significant difference in the Glu-7PH quantities in cardiac blood, mycardium, spleen, kidney, brain and right hindlimb muscle, but there was a significant difference in the Glu-7PH quantities in the liver and lung.@*CONCLUSIONS@#The mycardium, cardiac blood, liver, lung, kidney, brain and hindlimb muscle of rabbits can be used as appropriate samples for Glu-7PH detection. However, it should be noted that Glu-7PH was redistributed postmortem in rabbit liver and lung.

Screening Biomarkers of Sudden Coronary Death Based on mRNA Expression Profile of Rat Myocardial Tissues / 法医学杂志

OBJECTIVES@#To explore the differential expression of messenger RNA (mRNA) in myocardial tissues of rats with sudden coronary death (SCD), and to provide ideas for the forensic identification of SCD.@*METHODS@#The rat SCD model was established, and the transcriptome sequencing was performed by next-generation sequencing technology. Differentially expressed genes (DEGs) in myocardial tissues of SCD rats were screened by using the R package limma. A protein-protein interaction (PPI) network was constructed by using the STRING database and Cytoscape 3.8.2 on DEG, and hub genes were screened based on cytoHubba plug-in. Finally, the R package clusterProfiler was used to analyze the biological function and signal pathway enrichment of the selected DEG.@*RESULTS@#A total of 177 DEGs were associated with SCD and were mainly involved in the renin-angiotensin system and PI3K-Akt signaling pathway. The genes including angiotensinogen (AGT), complement component 4a (C4a), Fos proto-oncogene (FOS) and others played key roles in the development of SCD.@*CONCLUSIONS@#Genes such as AGT, C4a, FOS and other genes are expected to be potential biomarkers for forensic identification of SCD. The study based on mRNA expression profile can provide a reference for forensic identification of SCD.

Gene Expression Profiles at Different Time Points after Acute Myocardial Infarction in Mice / 法医学杂志

OBJECTIVES@#To explore the mRNA differential expressions and the sequential change pattern in acute myocardial infarction (AMI) mice.@*METHODS@#The AMI mice relevant dataset GSE4648 was downloaded from Gene Expression Omnibus (GEO). In the dataset, 6 left ventricular myocardial tissue samples were selected at 0.25, 1, 4, 12, 24 and 48 h after operation in AMI group and sham control group, and 6 left ventricular myocardial tissue samples were selected in blank control group, a total of 78 samples were analyzed. Differentially expressed genes (DEGs) were analyzed by R/Bioconductor package limma, functional pathway enrichment analysis was performed by clusterProfiler, protein-protein interaction (PPI) network was constructed by STRING database and Cytoscape software, the key genes were identified by Degree topological algorithm, cluster sequential changes on DEGs were analyzed by Mfuzz.@*RESULTS@#A total of 1 320 DEGs were associated with the development of AMI. Functional enrichment results included cellular catabolic process, regulation of inflammatory response, development of muscle system and vasculature system, cell adhesion and signaling pathways mainly enriched in mitogen-activated protein kinase (MAPK) signaling pathway. The key genes of AMI included MYL7, TSC22D2, HSPA1A, BTG2, NR4A1, RYR2 were up-regulated or down-regulated at 0.25-48 h after the occurrence of AMI.@*CONCLUSIONS@#The functional signaling pathway of DEGs and the sequential expression of key genes in AMI may provide a reference for the forensic identification of AMI.

Determination of Escitalopram in Biological Samples by Dispersive Liquid-Liquid Microextraction Combined with GC-MS/MS / 法医学杂志

Objective To establish a method for determination of escitalopram in biological samples by ultrasound-assisted ionic liquid-dispersive liquid-liquid microextraction combined with gas chromatography-tandem mass spectrometry （GC-MS/MS） and provide evidences for forensic determination of cases related to escitalopram. Methods The 1-hexyl-3-methylimidazolium hexafluorophosphate （[C6MIM][PF6]） was selected as an extract solvent to process biological samples. Ultrasound-assisted extraction was used on the samples. Then the samples were detected by GC-MS/MS. Results The linear range of escitalopram in blood and liver were 5.56-1 111.10 ng/mL and 0.025-5.00 mg/g, respectively. The correlation coefficient （r） were greater than 0.999, limit of detection （LOD） were 4.00 ng/mL and 2.00 μg/g, limit of quantitation （LOQ） were 14.00 ng/mL and 6.00 μg/g, respectively. The extraction recovery rates were all greater than 50%, the interday and intraday precision were less than 20%. Escitalopram was detected in blood and liver samples from the actual poisoning case by this method with a content of 1.26 μg/mL and 0.44 mg/g, respectively. Conclusion The ultrasound-assisted ionic liquid-dispersive liquid-liquid microextraction combined with GC-MS/MS is environment friendly, rapid, has good enriching effect and consumes less organic solvent and can be used for forensic determination of escitalopram related cases.

Determination of the Content of 4-FMA in Rat Plasma Samples by HPLC-MS/MS Method / 法医学杂志

Objective To develop a high performance liquid chromatography-tandem mass spectrometry （HPLC-MS/MS） method for the determination of the content of 4-fluoromethamphetamine （4-FMA） in rat plasma, and to provide a methodological basis for the study of the toxicokinetics of 4-FMA in rats. Methods Rat plasma samples were added into internal standard methamphetamine （MA）. Its proteins were precipitated with methanol and then separated with Poroshell 120 EC-C18 chromatographic column. A 0.1% formic acid aqueous solution and a 0.1% formic acid acetonitrile solution were used as the mobile phase at the flow rate of 0.4 mL/min. Electrospray ionization source was used for detection in the multiple reaction monitoring （MRM） mode. Results The linear relationship was good when the mass concentration of 4-FMA in plasma samples was in the range of 5-1 000 ng/mL （r>0.999）. The limit of detection （LOD） was 3 ng/mL and the limit of quantification （LOQ） was 5 ng/mL. The accuracy was expressed as relative error （RE）, and in the range of ±5%, the intra-day precision and inter-day precision （relative standard deviation, RSD） less than 9%, and the extraction recovery rate was more than 90%. The analysis and detection of plasma samples were completed within 2.5 min. Conclusion This study developed a HPLC-MS/MS method for the determination of 4-FMA in rat plasma samples. This method is accurate, rapid, simple and sensitive and can be applied to the study of toxicokinetics of 4-FMA.

Determination of Endosulfan Concentrations in Biological Samples by GC-MS/MS / 法医学杂志

OBJECTIVES@#To establish an analytical method of the endosulfan concentrations （α-endosulfan and β-endosulfan） in biological samples by GC-MS/MS. To observe the distribution of endosulfan in aquatic animals and provide experimental evidence for forensic identification of relevant cases.@*METHODS@#Acetonitrile was added to the blood and muscle samples for precipitating the protein. The endosulfan concentrations were determined by GC-MS/MS in multiple reaction monitoring mode. Qualitative analysis was performed according to the retention time and ion rate, and quantitative analysis was performed by external standard working curve method.@*RESULTS@#In blood samples, the calibration curves of α-endosulfan and β-endosulfan ranging from 0.062 5 to 10 μg/mL had good linear relationship, the correlation coefficients （r） of which were >0.99. The limits of detection （LOD） were 1 ng/mL and 2 ng/mL and the limits of quantification （LOQ） were 4 ng/mL and 8 ng/mL, respectively. In muscle samples, the calibration curves of α-endosulfan and β-endosulfan ranging from 0.062 5 to 10 μg/g, the r of which were >0.98. The LOD were 1 ng/g and 4 ng/g and the LOQ were 4 ng/g and 16 ng/g, respectively. The accuracy of α-endosulfan and β-endosulfan was 90.76%-108.91% both in blood and muscle samples, the interday and intraday precision were 2.35%-8.71% and 5.44%-10.29%, respectively. In poisoning cases, endosulfan were detected in all parts of fish and crab and the content difference was statistically significant.@*CONCLUSIONS@#The endosulfan detection method based on GC-MS/MS established in the present study is rapid, sensitive and accurate, which can be applied to the endosulfan detection in traces biological samples. The distribution of endosulfan in fish and crab was different, which can provide evidence to the sample collection and analysis for toxicological analysis in relevant forensic identification.

Morphology and volume of maxillary canine pulp cavity for individual age estimation in forensic dentistry / Morfología y volumen de la cavidad de pulpa del canino maxilar para la estimación de la edad individual en odontología forense

Age estimation plays a very important role in individual recognition in forensic dentistry. Morphological data of 3D pulp cavity of maxillary canines were acquired by oral and craniofacial CT scans. In accordance with inclusion criteria, CT data of 103 patients (51 males and 52 females) were collected at the Department of Radiology, Stomatological Hospital, Shanxi Medical University, China from September 2015 to August 2016. Mimics 17.0 software was used to measure pulp volume of maxillary canines and tooth volume, and to calculate the ratio of pulp volume/tooth volume. SPSS 16.0 software was utilized to analyze and establish database. Linear regression analysis was applied to process data and to establish a linear regression equation for individual age: Y=69.137-621.200 (pulp volume/tooth volume), R=0.544. Subjects were grouped according to gender, deriving the inferred function of male age: Y=64.333-468.811 (pulp volume/tooth volume), R=0.435; the inferred function of female age: Y=76.445-843.186 (pulp volume/tooth volume), R=0.691. The ratio of pulp volume to tooth volume can be used to infer individual age, and can provide a new method and pathway for individual recognition in forensic dentistry.

La estimación de la edad juega un papel importante en el reconocimiento individual en la odontología forense. Los datos morfológicos de la cavidad pulpar tridimensional de los caninos maxilares fueron adquiridos por tomografía computarizada oral y craneofacial. De acuerdo con los criterios de inclusión, se recolectaron datos de 103 pacientes (51 hombres y 52 mujeres) en el Departamento de Radiología del Hospital de Estomatología de la Universidad de Medicina de Shanxi, desde septiembre de 2015 hasta agosto de 2016. Se utilizó el software Mimics 17.0 para medir el volumen de pulpa de los caninos maxilares y el volumen del diente, además, se calculó la relación entre el volumen de la pulpa y el volumen del diente. Se utilizó el software SPSS 16.0 para analizar y establecer las bases de datos. El análisis de regresión lineal se aplicó a los datos del proceso y para establecer la edad individual se aplicó una ecuación de regresión lineal: Y = 69.137-621.200 (volumen de la pulpa / volumen del diente), R = 0.544. Los sujetos se agruparon según el sexo, derivando la función inferida de la edad masculina: Y = 64.333-468.811 (volumen de la pulpa / volumen del diente), R = 0.435; La función inferida de la edad de la mujer: Y = 76.445-843.186 (volumen de la pulpa / volumen del diente), R = 0.691. La relación entre el volumen de la pulpa y el volumen del diente puede usarse para inferir la edad individual y puede proporcionar un nuevo método y forma para el reconocimiento individual en la odontología forense.

Stability of estazolam in dog tissues preserved in formaldehyde solution / 法医学杂志

OBJECTIVE@#To investigate the stability of estazolam in biological samples preserved in formaldehyde solution.@*METHODS@#The dog was given intragastric administration of estazolam with a dose of 37.6 mg/kg and killed 2 h later. Heart, liver, kidney and brain of the dog were cut up into 1 g and preserved in 4% formaldehyde solution respectively. The content of estazolam in biological samples and formaldehyde solution were analyzed by HPLC at different times.@*RESULTS@#The content of estazolam in heart, liver, kidney and brain or in formaldehyde solution reduced gradually followed with the extention of preservation time. At the 63rd day, estazolam content in four tissues were 0.8%, 1.7%, 1.0% and 2.2% of the original content respectively.@*CONCLUSION@#Estazolam in tissues can diffuse into formaldehyde solution and decomposed quickly, so biological samples contained estazolam should not be preserved in formaldehyde solution.

Decomposition kinetics of bupivacaine in biological specimens / 法医学杂志

OBJECTIVE@#To study on the decomposition kinetics of bupivacaine in brain, blood and urine, which were collected from dogs executed by bupivacaine and stored in different conditions.@*METHODS@#Dogs were given arachnoid cavity anesthesia with bupivacaine. Then the brain, blood and urine were collected and divided equally to three groups stored in 20, 4 and -20 degrees C respectively. The concentrations of bupivacaine at different days were determined by the GC. The equation and half-time period of decomposition kinetics were imitated and calculated with WinNolin program.@*RESULTS@#The decomposition kinetics of bupivacaine in the dogs' brain, blood and urine were fit to the first order kinetics. The common equation was lgC = lgCo-kt/2.303 and k was the decomposition constant of first order reaction.@*CONCLUSION@#Bupivacaine in the brain, blood and urine specimens were found to be decomposed at various environments for storage. The higher temperature for storage, the faster of decomposition reaction.

The effect of temperature on the postmortem redistribution of bupivacaine in epidural anesthesia death dogs / 法医学杂志

OBJECTIVE@#To establish the models of postmortem redistribution(PMR) in dogs with epidural anesthesia and to investigate the effect of temperature on the PMR of Bupivacaine.@*METHODS@#Eighteen male dogs were executed by epidural anesthesia with a dose of 5 mg/kg bupivacaine hydrochloride and randomly divided into three groups, room temperature (20-23 degrees C) group, 4 degrees C group and -20 degrees C group. The cardiac blood, peripheral blood, liver and cerebrum were collected at 0, 2, 4, 8, 24, 48, 72, 96, 120h postmortem. The contents of bupivacaine in those samples were analyzed by GC-NPD and GC-MS, the difference among three groups were compared.@*RESULTS@#The bupivacaine PMR of room temperature group was evident and complex in cardiac blood, peripheral blood and cerebrum. The PMR of 4 degrees C group was weaker and slower than that of normal temperature group. The bupivacaine PMR of the -20 degrees C group was the weakest in three groups.@*CONCLUSION@#PMR of bupivacaine will happen in epidural anesthesia death dogs, but it could be delayed or prevent by low temperature storage.

Effect of temperature and time on stability of ketamine in biological samples / 法医学杂志

OBJECTIVE@#The stability of ketamine in biological samples was studied under different storage temperature and time.@*METHODS@#The rabbits were given intragastric administration of ketamine with a dose of 150 mg/kg and were sacrificed after 30 minutes. Blood, liver, kidney and brain of the rabbits were stored at room temperature (between 18 degrees C and 24 degrees C) and -20 degrees C. The specimens were analyzed at different times by GC-MS and GC-NPD.@*RESULTS@#At -20 degrees C, the concentration of ketamine decreased in all of samples (P < 0.05) within 30 days. The concentration of ketamine increased in all of samples stored at room temperature after 5 days(P < 0.05).@*CONCLUSION@#The stability of ketamine in biological samples stored at -20 degrees C was better than that at room temperature. The samples suspected containing ketamine should be stored at -20 degrees C and should be tested as soon as possible.

The stability of carbon monoxide in stored blood samples / 法医学杂志

Based on the records of carboxyhemoglobin in blood samples stored for recent years, the stability of carboxyhemoglobin in these samples could be affected by the containers, the storage temperatures, the volumes of air above the blood, the saturation of the initial carboxyhemoglobin and preservatives added in these blood samples, among which the storage temperatures, the volumes of air above the blood and the saturation of the initial carboxyhemoglobin are the major influence factors.

The study on identification of lidocaine in blood and CSF by GC/MS / 法医学杂志

OBJECTIVE@#To establish a rapid and simple gas chromatographic-mass spectric method for qualitative and quantitative analysis of lidocaine in blood and cerebrospinal fluid(CSF).@*METHODS@#Following an acidification of HCl, blood or CSF was alkalinized with NaOH (pH=9) and extracted with ether for two times. Evaporated in a water bath and with an air velocity of nitrogen gas, extract was dissolved with ethanol and analyzed by a gas chromatographic-mass spectrum method, lidocaine was analyzed qualitatively and quantitatively by GC/MS (SIM:86, 58, 72, 87).@*RESULTS@#Linear range of lidocaine detected in blood or CSF by this method is 1.0-60.0 microg x mL(-1) (r=0.9999), the minimum detected concentration of lidocaine was 0.02 microg x mL(-1) (S/N=3), recovery is at 85%-103%. This method was used in the determination of lidocaine in dog model died of the anesthesia with lidocaine.@*CONCLUSION@#This study provided a gas chromatographic-mass spectric analysis for lidocaine in blood and CSF. This method was more selective, little interferefering, more sensitivities and simpler. It could be used in the detection of lidocaine in biological fluids.