[Deep Learning-Based Cardiac Imaging Data Measurement and Its Application in Diagnosis of Sudden Cardiac Death].

ABSTRACT: In the field of forensic medicine, diagnosis of sudden cardiac death is limited by subjective factors and manual measurement methods, so some parameters may have estimation deviation or measurement deviation. As postmortem CT imaging plays a more and more important role in the appraisal of cause of death and cardiopathology research, the application of deep learning such as artificial intelligence technology to analyze vast amounts of cardiac imaging data has provided a possibility for forensic identification and scientific research workers to conduct precise diagnosis and quantitative analysis of cardiac diseases. This article summarizes the main researches on deep learning in the field of cardiac imaging in recent years, and proposes a feasible development direction for the application of deep learning in the virtual anatomy of sudden cardiac death at present.

Research Progress of Metabolomics in Forensic Pathology.

ABSTRACT: Metabolomics is an interdisciplinary subject that rose in the post-genomic era, which focuses on quantitative study of the response of living organisms to outside stimulation and pathophysiological changes, as well as multiple dynamic response of the level of in vivo metabolites caused by genetic mutation. It is extensively used in basic research of system biology, materia medica, clinical medicine, etc. In the forensic field, metabolomics mainly focuses on forensic toxicology, but with the generalization of certain techniques, it's foreseeable that metabolomics has a broad research prospect in forensic pathology. This article summarizes the major analysis techniques and methods of metabolomics, describes the research status of metabolomic techniques in the field of forensic pathology application research, including postmortem interval and death cause. Moreover, this article summarizes and discusses the potential applicable areas, in order to provide reference for relative research and application.

Application of Virtual Anatomy Technology in Postmortem Examination of Medical Dispute Cases.

ABSTRACT: Objective To discuss the application value of CT scanning technology in cause of death determination of medical dispute cases. Methods From July 2017 to December 2018, postmortem CT imaging data of 12 medical dispute cases were collected. CT imaging diagnosis results and anatomy findings as well as differences between antemortem and postmortem CT diagnosis were compared. The advantages and disadvantages of CT routine tests of the cadavers in terms of the diagnosis of disease and damage were analyzed. Results The comparison between CT imaging diagnosis and anatomical findings showed that CT scans had advantages in the diagnosis of disease and damage with large differences in density changes, such as atelectasis, pneumonia, calcification, fracture and hemorrhage, etc. The comparison of CT diagnosis in antemortem and postmortem examination showed that the cadavers of medical dispute cases were well preserved and that postmortem CT scan was meaningful for the diagnosis of antemortem diseases. Conclusion Virtual anatomy technology has a relatively high application value in postmortem examination of medical dispute cases. It can provide effective information for the appraisers before the autopsy and can also provide a reference for cause of death analysis when the anatomy cannot be performed.

[Research Status of Postmortem MSCT Angiography in Forensic Science].

ABSTRACT: Virtual autopsy is a new technique for investigating the morphological changes of cadaveric tissues and organs by medical imaging technology. It has been widely used in the identification of causes of death. Multislice spiral computed tomography （MSCT） has become a routine inspection method in some identification institutions, although it cannot completely replace traditional autopsy, it plays a key auxiliary or substitute role in the identification of certain abnormal causes of death. Plain MSCT scan cannot visualize cadaveric vessels, but can perform cadaveric angiography to determine vascular injury or disease. This technology has entered a rapid development period in recent years, and has made a considerable progress in contrast agent, perfusion methods and imaging methods. This article summarizes several common cadaveric MSCT angiography methods, such as systemic angiography, angiography through cardiopulmonary resuscitation, targeted angiography, and angiography by cardiac puncture, and analyzes and compares the application prospects.

Research Progress in Virtopsy of Drowning.

ABSTRACT: Dead bodies found in the water are not all caused by drowning. The important task of forensic identification is to distinguish between entering the water before and after death, and to clarify the cause of death. In the practice of forensic identification, drowning is generally diagnosed on the basis of comprehensive considerations such as cadaveric signs, histopathological examinations, and diatom tests, with the exclusion of other causes of death. The emergence of virtopsy techniques provides new insights for the diagnosis of drowning. This paper reviews the post-mortem imaging studies of sinus and mastoid small chambers, respiratory tracts, lung tissues, gastrointestinal tracts and blood in the corpses in recent years. The value, potential of virtopsy in the diagnosis of drowning is discussed, with the prospects of its development direction.

Characteristic Changes and 3D Virtual Measurement of Lung CT Image Parameters in the Drowning Rabbit Model.

OBJECTIVES: To use virtual anatomy technique in the analysis of post-mortem characteristic changes of CT images in the experimental drowning rabbit model and the related parameters in 3D virtual model, so as to explore its application value in the diagnosis of drowning in forensic pathology. METHODS: A model of drowning rabbits was established, with animal models of hemorrhagic shock and mechanical asphyxia as the controls. CT scan was performed on the experimental animals, and the differences in imaging features between the groups were compared by morphological reading of the tomographic images. CT data were imported into Mimics 14.0 software for 3D modeling. The CT values and lung volumes were calculated by the software, and the differences on CT values and lung volumes brought by different causes of death were analyzed. RESULTS: The CT images of lungs in the drowning group showed characteristic ground-glass opacity （diffuse and uniform density increase）. There were no obvious abnormalities in hemorrhagic shock group, and only a few similar changes were found in the mechanical asphyxia group. Compared with the controls, the CT values and the lung volumes in the drowning group were significantly increased P<0.05. CONCLUSIONS: Based on post-mortem lung imaging, the combination of CT value and lung volume changes can effectively reflect the virtual anatomical features in drowning, and provide a diagnostic basis for the forensic identification of drowning.

Analysis of Forensic Sciences Literature in SCIE from 2008 to 2017.

OBJECTIVES: To analyze the literature on forensic sciences indexed in Science Citation Index Expanded （SCIE） in recent 10 years, and to understand the research status, characteristics and trends in the field of forensic sciences. METHODS: Literature on forensic sciences from 2008 to 2017 in Web of Science （WoS） was retrieved. The documents number and geographical distribution, document types, source titles, organizations, research areas, authors, funding agencies, and the high cited articles were detected. The impact factors （IF） of journals were retrieved in Journal Citation Reports （JCR）. The data were analyzed with descriptive statistics. RESULTS: From 2008 to 2017, there were 21 001 documents on forensic sciences in SCIE. The main document type was articles, with English as the major language. With regards to research areas, pathology has the largest number of papers worldwide, and genetics and heredity has the largest number of publications in mainland China. Among the 18 journals where the documents was published, Forensic Science International ranks the first on publication count, and Forensic Science International Genetics has the highest IF （5.637） in the JCR 2017. In 2017, the number of papers from mainland China increased by 48.50% compared with 2016, which was higher than the global increase （32.63%） and the top-5 countries in terms of number of publications （the US, Germany, the UK, Australia, Italy）. The average document count per organization is 1.98 worldwide and 1.17 in mainland China, respectively. The publication number per author is 0.53 worldwide and 0.36 in mainland China, respectively. Around 28.17% of the publications were funded, with National Natural Science Foundation of China （NSFC） as the Top 1 funding agency （192 papers）. Among the documents with citations, the most cited publication has been cited for 366 times. CONCLUSIONS: The yearly numbers of publications on forensic sciences are increasing during recent 10 years. Focusing on the mainland China, there would be more high-quality papers with the steady funding of NSFC.

Research Progress on Detection Methods of Amphetamines in Human Hair.

Amphetamines are chemical synthetic drugs that are becoming increasingly popular in China. As a common sample in the inspection of poisons, hair has the advantages of easy storage, good stability, and long detection time compared with traditional human body fluid samples （blood, urine）, thus possesses an unique application value in the field of forensic toxicology analysis. By now, methods for detecting amphetamines in human hair have been widely used, and validity of the results has been recognized and adopted by the court. This paper reviews domestic and foreign research progress of the detection of amphetamines in hair samples, including the pretreatment and analytic methods.

Research Progress on Postmortem Changes of Computed Tomography Imaging Characteristics on Corpses.

ABSTRACT: Postmortem changes on corpses appear immediately after death, and can transform the original structure characteristics of the corpse to different degrees as well as show specific changes on computed tomography （CT） images, sometimes with false positives and false negatives, influencing the identification of injuries or diseases. This paper systematically summarizes the postmortem changes of computed tomography imaging characteristics on corpses, to further expand the application of virtopsy in the practices of forensic pathology identification, and provide reference for the identification of injuries, diseases and changes after normal death.

Infrared Spectral Characteristics of Electrical Injuries on Swine Skin Caused by Different Voltages Based on Machine Learning Algorithms.

OBJECTIVES: To explore infrared spectrum characteristics of different voltages induced electrical injuries on swine skin by using Fourier transform infrared-microspectroscopy （FTIR-MSP） combined with machine learning algorithms, thus to provide a reference to the identification of electrical skin injuries caused by different voltages. METHODS: Electrical skin injury model was established on swines. The skin was exposed to 110 V, 220 V and 380 V electric shock for 30 s and then samples were took, with normal skin tissues around the injuries as the control. Combined with the results of continuous section HE staining, the FTIR-MSP spectral data of the corresponding skin tissues were acquired. With the combination of machine learning algorithms such as principal component analysis （PCA） and partial least squares-discriminant analysis （PLS-DA）, different spectral bands were selected （full band 4 000-1 000 cm-1 and sub-bands 4 000-3 600 cm-1, 3 600-2 800 cm-1, 2 800-1 800 cm-1, and 1 800-1 000 cm-1）, and various pretreatment methods were used such as orthogonal signal correction （OSC）, standard normal variables （SNV）, multivariate scatter correction （MSC）, normalization, and smoothing. Thus, the model was optimized, and the classification effects were compared. RESULTS: Compared with simple spectrum analysis, PCA seemed to be better at distinguishing electrical shock groups from the control, but was not able to distinguish different voltages induced groups. PLS-DA based on the 3 600-2 800 cm-1 band was used to identify the different voltages induced skin injuries. The OSC could further optimize the robustness of the 3 600-2 800 cm-1 band model. CONCLUSIONS: It is feasible to identify electrical skin injuries caused by different voltages by using FTIR-MSP technique along with machine learning algorithms.

[Research Progress of MALDI-TOF-IMS in Biomedicine and Its Application Prospect in Forensic Sciences].

Matrix-assisted laser desorption/ionization time-of-flight imaging mass spectrometry （MALDI-TOF-IMS） can analysis unknown compounds in sections and obtain molecule imaging by scanning biological tissue sections, which has become a powerful tool for the research of biomarker, lipid distribution and drug metabolism, etc. This article reviews the application of this technique in protein identification, clinical application, drug discovery, lipid research and brain injury.

[Analysis of Differentially Expressed Proteins Distribution in the Rat Brains with DAI by MALDI-TOF-IMS].

OBJECTIVES: To establish the imaging mass spectrometry for analysis of differentially expressed proteins distribution in the rat brains with diffuse axonal injury （DAI） based on matrix assisted laser desorption/ionization-time of flight imaging mass spectrometry （MALDI-TOF-IMS）. METHODS: MALDI-TOF-IMS scanning were conducted on the brains of DAI group and control group in the m/z range of 1 000 to 20 000 using AutoflexⅢ MALDI-TOF spectrometer. ClinProTool 2.2 software was used for statistical analysis on the data of two groups, and then the differentially expressed proteins were picked out to conduct imaging. The distribution of the proteins with different m/z in the rat brains was observed. RESULTS: Five proteins with different m/z, including 4 963, 5 634, 6 253, 6 714 and 7 532, differentially expressed in the rat brains with DAI. CONCLUSIONS: MALDI-TOF-IMS can be used for studying the differentially expressed proteins in rat brains with DAI and the analysis method is established for exploring the distribution of differentially expressed proteins in the rat brains with DAI using imaging mass spectrometry.

Effects of acupotomylysis on basic fibroblast growth factor and CD34 levels in rabbits with third lumbar vertebral transverse foramen syndrome.

This study observed the local tissue homogenates in rabbits with third lumbar vertebral transverse foramen syndrome and explored the mechanism of acupotomylysis in local tissue revascularization. Thirty Japanese white rabbits were randomly divided into the following 5 groups of 6 rabbits each: normal, model, acupotomy, electroacupuncture (EA), and acupotomy-EA groups. All except the normal group were comprised of animal models of third lumbar vertebral transverse foramen syndrome prepared by embedding sponge in the left third lumbar transverse process. The rabbits in the acupotomy and EA groups underwent bilateral acupotomylysis intervention; those in the acupotomy-EA group underwent acupotomylysis and EA interventions. On the 28th day after modeling, the double-antibody ELISA was used to detect b-FGF and CD34 levels in the serum and homogenates of a muscle tissue sample from the left side of the third lumbar transverse process. The b-FGF levels in local muscle homogenates were significantly higher in the modeled rabbits than in the normal rabbits (P < 0.01), and the CD34 levels in the modeled group were significantly lower than in the normal group (P < 0.01). The b-FGF and CD34 levels in the EA, acutopomy, and acutopomy-EA groups were significantly lower than those in the modeled group (P < 0.01); the CD34 levels were significantly higher in the acupotomy-EA group than in the model group (P < 0.05); and the differences among the EA, acupotomy, and acupotomy-EA groups were not significant (P > 0.05). In conclusion, acupotomylysis regulates the levels of b-FGF and CD34 levels in serum and muscle tissue as well as local tissue revascularization.

[In vivo distribution and expression after skin injury of fibronectin splicing variants].

OBJECTIVE: In order to develop new criteria and to select positive controls for forensic medicine, experiments on in vivo distribution and expression after skin wound of fibronectin splicing variants, EIIIA and EIIIB were studied. METHODS: Rat tissues were homogenized to extract total RNA which was then amplified by RT-PCR technique. RESULTS: (1) EIIIA+ and EIIIB+ of normal skin were not expressed, whereas EIIIA+ after 18 hours' injury was expressed abundantly. No obvious charge of EIIIB+ was detected. The differences between results of using two methods of injury were not significant. (2) The distribution of fibronectin variants in different adult organs were in the following order: brain > heart > liver. CONCLUSIONS: EIIIA+ may be used as a sensitive criterion for research of skin injury.

[Fos expression in rat skin after different incised wound healing interval].

OBJECTIVE: To investigate the expression of c-fos in rats' skin during wound healing. METHODS: Immunohistochemistry was conducted on paraffin section from incised wounding model of rat skin. RESULTS: Fos protein improved from the time of 10 min after wounding in the wound edge, then it reached peak at 3 h. 24 h after injury, the quantity of Fos expression had no difference with that of normal skin. CONCLUSION: Fos is sensitive after wound, but should be used with other criteria in wounding interval estimation as it's unstediness.

[Study on the expression of fibronectin after cerebral contusion in rats for timing of injuries].

An experimental model of reproducible focal cerebral contusions in rats was made by a free-drop impacting right hemisphere. The expression of fibronectin and its mRNA after cerebral contusion were detected respectively by immunohistochemical staining and in situ hybridization. Results indicated that the expression of fibronectin and its mRNA increased after injury, and there existed a relationship between increased fibronectin and its mRNA and different intervals after brain injury. It is inferred that the expression of fibronectin and its mRNA can be used for timing of brain injuries and distinguishing antemortem and postmortem brain contusions.

[The expression of splicing fibronectin variants of cutaneous injuries in rats].

In situ hybridization with Digoxingenin labeled probes were used to build the relationship between incised cutaneous wounding intervals and the expression of splicing fibronectin variants (total, E III A and E III B Variants) in rats. The results showed that all forms of FN variants increased notably with the wounding time going on. E III A and E III B Variants were expressed abundantly 30 and 60 minutes after injury, while few in normal skin.

Isolation of a calreticulin-like calcium binding protein from bovine brain.

Intracellular calcium levels are stringently regulated in all cells. The nature of this regulation is incompletely understood, but recent evidence indicates that the endoplasmic reticulum plays an important role in sequestering intracellular calcium. Using methods for isolating both calsequestrin and calreticulin, we have isolated a 58 kDa, high capacity calcium binding protein that exists in microsomes that shift their density in an oxalate-mediated density shift assay. This protein which we call CBP-58 bears similarities to the endoplasmic reticulum protein, calreticulin, in that it has a pI of 4.7 containing approximately 30% glutamate and aspartate, has a high capacity for calcium, and stains blue with the carbocyanine dye, 'Stains-all'. Peptide, amino acid, nucleotide and immunochemical analyses reveal further similarities between CBP-58 and calreticulin, but also some marked differences. Its tissue distribution suggests it is highly enriched in brain versus other tissues. We believe that CBP-58 is a calreticulin-like protein and that differences in the amino acid composition and sequences may reflect species diversity in calreticulin.