New Advances, Challenges and Opportunities in Forensic Applications of Microbiomics / 法医学杂志

The succession of microbiota is closely associated with several essential factors, including race, sex, health condition, lifestyle, postmortem interval, etc., and it has great potential application value in forensic medicine. This paper summarizes recent studies on the forensic applications of the microbiome, including individual identification, geographical feature identification, origin identification of the tissue or body fluid, and postmortem interval estimation, and introduces the current machine learning algorithms for microbiology research based on next-generation sequencing data. In addition, the current problems facing forensic microbiomics such as the extraction and preservation of samples, construction of standardization and database, ethical review and practical applicability are discussed. Future multi-omics studies are expected to explore micro ecosystems from a comprehensive and dynamic perspective, to promote the development of forensic microbiomics application.

Visualization of Literature Information on Postmortem Interval Estimation Indexed by CNKI Database from 1990 to 2020 / 法医学杂志

OBJECTIVES@#To explore the development process of the postmortem interval (PMI) research in China from January 1990 to August 2020, research hotspots in different periods, authors and cooperation between institutions, and to provide a reference for the better development of PMI inference research through the visualization of the literature information of the PMI estimation research indexed in China National Knowledge Infrastructure (CNKI).@*METHODS@#The information visualization analysis software CiteSpace 5.7.R1 was used to carry out big data analysis on hotspots, high-frequency keywords, authors, institutions and other information in the research literature on PMI inference from January 1990 to August 2020 indexed in CNKI.@*RESULTS@#The peak time of publication of PMI was from 2006 to 2010 with 114 articles. In keyword co-occurrence network, the effective hot words were forensic entomology, DNA content analysis and some emerging words such as artificial intelligence and big data. In the cooperation network of institutions, the high-frequency institutions were mainly the scientific research institutions. The author cooperation network showed a trend of co-aggregation and multi-cooperation.@*CONCLUSIONS@#With the development of science and technology, the research on PMI estimation based on traditional methods is mature and novel strategies are emerging. Big data and artificial intelligence combined with forensic science provide new research directions on PMI estimation.

Estimating Postmortem Interval Using Intestinal Microbiota Diversity Based on 16S rRNA High-throughput Sequencing Technology / 法医学杂志

OBJECTIVES@#To explore the correlation between intestinal microbiota and postmortem interval(PMI) in rats by using 16S rRNA high-throughput sequencing technology.@*METHODS@#Rats were killed by anesthesia and placed at 16 ℃, and DNA was extracted in caecum at 14 time points of 0, 1, 2, 3, 5, 7, 9, 12, 15, 18, 21, 24, 27 and 30 d after death. The 16S rRNA high-throughput sequencing technology was used to detect intestinal microbiota in rat cecal contents, and the results were used to analyze the rat intestinal microbiota diversity and differences.@*RESULTS@#The total number of intestinal microbial communities did not change significantly within 30 days after death, but the diversity showed an upward trend. A total of 119 bacterial communities were significantly changed at 13 time points after death. The models for PMI estimation were established by using partial least squares (PLS) regression at all time points, before 9 days and after 12 days, reaching an R2 of 0.795, 0.767 and 0.445, respectively; and the root mean square errors (RMSEs) were 6.57, 1.96 and 5.37 d, respectively.@*CONCLUSIONS@#Using 16S rRNA high-throughput sequencing technology, the composition and structure of intestinal microbiota changed significantly within 30 d after death. In addition, the established PLS regression model suggested that the PMI was highly correlated with intestinal microbiota composition, showing a certain time series change.

Application of Sarcosaprophagous Insects to Estimate the Postmortem Interval in 11 Cases / 法医学杂志

Objective To test the feasibility and accuracy of with sarcosaprophagous insects postmortem interval （PMI） estimation with sarcosaprophagous insects and provide references for estimation practice. Methods Eleven cases confirmed by the detection results, with complete entomological evidence were selected. The insect species, estimation results and true results involved in the cases were statistically analyzed and compared. Results Thirteen species of insects were found at the criminal scene, including Chrysomya megacephala （Fabricius）, Chrysomya rufifacies （Macquart）, Chrysomya nigripes （Aubertin）, Lucilia sericata （Meigen）, Hydrotaea spinigera Stein, Muscina stabulans （Fallén）, Sarcophagid （species were not identified）, Megaselia scalaris （Loew）, Hermetia illucens （Linnaeus）, Saprinus splendens （Paykull）, Creophilus maxillosus （Linnaeus）, Dermestes maculatus （De Geer） and Necrobia ruficollis （Fabricius）. The PMI of all eleven cases was within the range of estimated PMI. The estimated results of 72.73% cases were on the same day of the true results. Conclusion Sarcosaprophagous insects can estimate the PMI simply and conveniently. In cases where the PMI is within the time range of one generation of flies or beetles, the estimation results are relatively accurate. However, the estimation is less accurate when the PMI is beyond the time range.

Progress and Application of Entomological Evidence in Forensic Science / 法医学杂志

Entomological evidence provides entry points and clues for cases detection, in terms of estimation of the postmortem interval （PMI）, and place and cause of death. In recent years, the feasibility of entomological evidence in practice has been proved by theories and cases. It especially plays an important role in the investigation of cases with unnatural death, no monitoring, and highly corrupt cadaver. However, there are still some key issues to be further studied and standardized before the application of entomological evidence to forensic practice, to improve the effect of entomological evidence in forensic investigation and trial. This paper retrospectively reviews key studies of the application of entomological evidence in forensic science, mainly including discussion of forensic entomology inspection standard, identification studies of sarcosaprophagous insect species, collection of sarcosaprophagous insect growth and succession data under different environments and forensic entomotoxicology. With the rapid development of information technology and biotechnology, applying artificial intelligence and whole genome sequencing technology in forensic entomology has become a new research direction, which can improve the application value and range of entomological evidence in forensic science.

Critical quality attribute assessment of big brand traditional Chinese medicine: quality control method of Huangjing Zanyu Capsules based on chemical properties of characteristic components / 中国中药杂志

The chemical properties of characteristic components are significant to the manufacturing quality control of big brand traditional Chinese medicine. In this study, the Huangjing Zanyu Capsules were used as the research carrier to determine the content of five characteristic components including icraiin, emodin, schisandrin A, 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside, and osthole simultaneously by high-performance liquid chromatography(HPLC). The results showed that the chemical properties of five cha-racteristic components had a good linear relationship(r>0.999 9) within the quantitative range; the relative standard deviations(RSD) was 0.11%-2.0% and 0.25%-2.8% respectively for intra-day and inter-day precision; the RSD of repeatability was 1.8%-2.6%; the RSD of stability within 48 hours was 0.19%-2.8%, and the average recovery rate was 95.52%-100.1%, all meeting the requirements of pharmaceutical quantitative analysis. Additionally, the interval estimation method was used to directly reflect the distribution of samples with abnormal chemical properties of characteristic components, and the results showed ten samples were detected beyound the 95% control line of confidence level. Multivariate statistical process control(MSPC) method was used to monitor the abnormal samples of Huangjing Zanyu Capsules collectively, and the results showed that two samples were beyond the 95% control line of Hotelling's T~2 and three samples beyond the 95% control line of squared prediction error(SPE), indicating consistent quality control of Huangjing Zanyu Capsules. In conclusion, the proposed method is not only accurate and efficient but also a compensation for the traditional single-component quality control method, providing a scientific basis for the quality control in manufacturing process of Huangjing Zanyu Capsules. Furthermore, it could also serve as a reference method for the quality control in manufacturing big brand traditional Chinese medicine.

Métodos histoquímicos e inmunohistoquímicos para la estimación del Intervalo postmortem en tejidos humanos: una revisión / Histochemical and immunohistochemical methods for the postmortem interval estimation in human tissues: a review

El intervalo postmortem (IPM) es un importante desafío a resolver en patología forense, y consiste en poder determinar el tiempo transcurrido desde la muerte hasta el momento de la autopsia. Dada la poca confiablidad de algunos métodos por la gran influencia de factores externos, la Histoquímica (HQ) y la Inmunohistoquímica (IHQ), entre otros, han recibido considerable atención por sus niveles de objetividad en la investigación forense. Se presenta una revisión con búsqueda sistemática de estudios experimentales que apliquen métodos HQs e IHQs para la estimación del IPM sobre material cadavérico humano. Se identificaron 1053 artículos de los cuales 12 cumplieron con los criterios, a los que se agregaron 4 mediante una búsqueda manual (n=16 artículos). Alemania fue el país con más publicaciones destacando con 8 artículos. Las técnicas HQs de AgNORs, TRAP y PAS fueron utilizadas en 5 estudios (glándulas sudoríparas, piel, hígado, médula ósea y mucosa labial), mientras que las IHQs fueron empleadas con diferentes grupos antigénicos en 12 estudios (páncreas, cerebro, pulmón, tiroides, hígado, glándulas pituitarias, glándulas sudoríparas y mucosa gingival). Las estimaciones del IPM fueron posibles con márgenes entre 2-3 h. hasta los 20 días dependiendo de la técnica. El análisis de tejidos provenientes de cavidad oral asegura una vía no invasiva, de fácil acceso y bajo resguardo natural a la influencia de factores ambientales. Si bien no existe un método único que permita de manera confiable estas estimaciones, la introducción de nuevas técnicas permitiría evitar la producción de errores.

The postmortem interval (IPM) is an important challenge to be solved in forensic pathology, and it consists in determine the time elapsed since death until the autopsy. Given the low reliability of some methods due to the great influence of external factors, Histochemistry (HQ) and Immunohistochemistry (IHQ), among others, have received considerable attention for their levels of objectivity in forensic investigation. A scoping review of experimental studies that apply HQs and IHQs methods to estimate the MPI on human cadaveric material is presented. We identified 1053 articles, of which 12 met the criteria; we added 4 articles through a manual search (n = 16 articles). Germany was the most productive country, with 8 articles. HQ techniques of AgNORs, TRAP and PAS were used in 5 studies (on sweat glands, skin, liver, bone marrow and labial mucosa), while IHQs techniques were used with different antigenic groups in 12 studies (on pancreas, brain, lung, thyroid, liver, pituitary glands, sweat glands and gingival mucosa). IPM estimates were possible with margins between 2-3 hours up to 20 days depending on the technique. The analysis of oral tissues ensures a non-invasive route, easily accessible and under natural protection to the influence of environmental factors. Although there is no single method that reliably allows these estimates, the introduction of new techniques would prevent the production of errors.

Usos de la Estadística en artículos originales de revistas médicas cubanas / Uses of Statistics in original papers of Cuban medical journals

RESUMEN Se presentan resultados preliminares del proyecto de investigación "Usos de la estadística en artículos originales de la Revista Médica Electrónica de Matanzas", que corresponde al programa No. 2 (Organización, eficiencia y calidad de los servicios), código 152042.La información cuantitativa del proyecto se obtuvo por conducto de la aplicación de un diseño muestral sistemático con arranque aleatorio que proporcionó datos sobre nueve variables estadísticas medidas en 170 artículos originales de revistas médicas cubanas. Se calcularon las distribuciones porcentuales de cada variable. Predominó la aplicación de los estudios descriptivos y sus correspondientes medidas estadísticas. Se evidenció la poca aplicación de las estimaciones por intervalos, denotando una insuficiencia que debe ser eliminada. Los resultados proporcionan una aproximación al estado actual de la aplicación de la estadística en la redacción de artículos científicos originales (AU).

SUMMARY The authors present preliminary results of the research project "Uses of Statistics in original papers of Cuban medical journals", corresponding to the program Nr. 2 (Organization, efficacy and quality of the services), codex 152042. The quantitative information of the project was obtained applying a systematic sampling design with randomized onset that provided data on nine statistic variables measured in 170 original papers of Cuban medical journals. Percentage distributions of each variable were calculated. The application of descriptive studies and their correspondent statistical measures predominated. It was evidenced the scarce application of interval estimations, denoting an insufficiency that has to be eliminated. The outcomes provide an approximation to the current status of the statistics application in writing original scientific papers (AU).

An immunohistochemical study on the time-dependent expression of MIP-1?during healing of skin incised wound in mice / 重庆医科大学学报

Objective:To explore the expression of MIP-1? during healing of skin incised wound and the applicability of time-dependent expressions of MIP-1? to determination of wound age. Methods:An incised wound was made in the dorsal skin of mouse. Immunohistochemical and image-analysis techniques were employed in vital skin wounds 1h~14d after incision and postmortem incision 0.5~6h after death, and the non-incised mouse skin was used as contro1.Results:In the vital skin incisions,expression of MIP-1? began at 6h after incision,which increased subsequently,and peaked at 3d.The quantity of MIP-1?expression decreased and minimized in the specimens aged 14 days. In the non-wounded groups and postmortem incision groups MIP-1? was only detected as weak expression in the epidermic cells,sweat gland cells and endothelial cells. Conclusion:The time-dependent expression of MIP-1?during healing of skin incised wound may be used as a useful reference marker.