Analysis of the Development Trend in Forensic Odontology Based on CiteSpace.

OBJECTIVES: To realize the dynamic visualization of forensic odontology based on the bibliometrics methods, and capture the research hotspots and identify the future development trend. METHODS: Literature articles published from January 1995 to December 2020 were searched according to specific subject words in the core data set of Web of Science. The visualization analysis of publishing country, institution, discipline, author, co-cited journal and keywords was performed by CiteSpace 5.7.R5W software. RESULTS: The annual analysis of publications showed an upward trend of forensic odontology research literature year by year, with the number of annual publications more than 110 in the last five years. Developed countries were the main source of contributions and the average centrality was greater than 0.2. The research of forensic odontology involved multiple disciplines, including stomatology, biology, computer science and medical imaging, with a distinct interdisciplinary feature. A total of 115 nodes were obtained by keyword cluster analysis. The principal line of forensic odontology mainly included individual identification and age estimation and the emergence of hotspots was closely related to new technologies. Population-based odontology investigation, improvement of traditional dental age estimation method and dental age estimation based on new technology were popular research in forensic odontology. CONCLUSIONS: Developing countries urgently need to increase the focus on related research. It may be an important direction for the development of forensic odontology to establish and enrich the regional dental database, develop new odontology identification technology combined with frontier and high-end technology, and develop the identification program based on advanced information technology.

[The role of histone acetylation in the basolateral amygdala in morphine-associated memory in rats].

To examine the regulatory effect of histone acetylation on memory related molecules, 34 healthy male SD rats were randomly divided into control and basolateral amygdala (BLA) intracranial positioning operation groups. In the process of conditioned place preference (CPP) training, Trichostafin A (TSA) was administrated by the route of BLA and morphine was injected into enterocoelia with dimethyl sulfoxide or saline as control. Expression levels of H3K14 acetylation and brain-derived neurotrophic factor (BDNF) in BLA were evaluated by Western blotting.The results showed that CPP could be established by intraperitoneal injection of morphine. Compared with control groups, a stronger place preference was established and expression of H3K14 acetylation and BDNF was significantly increased in the group treated with TSA and morphine. In addition, there was a synergistic effect between morphine and TSA. Our results suggested that the level of histone acetylation in BLA is associated with the formation of morphine memory in rats. Inhibition of the activity of histone deacetylases in BLA can promote the formation of cue-associated memory induced by morphine and the involvement of BDNF in BLA maybe was regulated by histone acetylation.

Activation of the VpdmVGLUT1-VPM pathway contributes to anxiety-like behaviors induced by malocclusion.

Occlusal disharmony has a negative impact on emotion. The mesencephalic trigeminal nucleus (Vme) neurons are the primary afferent nuclei that convey proprioceptive information from proprioceptors and low-threshold mechanoreceptors in the periodontal ligament and jaw muscles in the cranio-oro-facial regions. The dorsomedial part of the principal sensory trigeminal nucleus (Vpdm) and the ventral posteromedial nucleus (VPM) of thalamus have been proven to be crucial relay stations in ascending pathway of proprioception. The VPM sends numerous projections to primary somatosensory areas (SI), which modulate emotion processing. The present study aimed to demonstrate the ascending trigeminal-thalamic-cortex pathway which would mediate malocclusion-induced negative emotion. Unilateral anterior crossbite (UAC) model created by disturbing the dental occlusion was applied. Tract-tracing techniques were used to identify the existence of Vme-Vpdm-VPM pathway and Vpdm-VPM-SI pathway. Chemogenetic and optogenetic methods were taken to modulate the activation of VpdmVGLUT1 neurons and the Vpdm-VPM pathway. Morphological evidence indicated the involvement of the Vme-Vpdm-VPM pathway, Vpdm-VPM-SI pathway and VpdmVGLUT1-VPM pathway in orofacial proprioception in wild-type mice and vesicular glutamate transporter 1 (VGLUT1): tdTomato mice, respectively. Furthermore, chemogenetic inhibition of VpdmVGLUT1 neurons and the Vpdm-VPM pathway alleviated anxiety-like behaviors in a unilateral anterior crossbite (UAC) model, whereas chemogenetic activation induced anxiety-like behaviors in controls and did not aggravate these behaviors in UAC mice. Finally, optogenetic inhibition of the VpdmVGLUT1-VPM pathway in VGLUT1-IRES-Cre mice reversed UAC-induced anxiety comorbidity. In conclusion, these results suggest that the VpdmVGLUT1-VPM neural pathway participates in the modulation of malocclusion-induced anxiety comorbidity. These findings provide new insights into the links between occlusion and emotion and deepen our understanding of the impact of occlusal disharmony on brain dysfunction.

[Association between polymorphism in DVWA and IL-1beta and Kashin-Beck disease].

OBJECTIVE: To investigate the association between IL-1beta and DVWA gene and Kashin-Beck disease (KBD). METHODS: Peripheral genomic DNA were extracted from 105 patients with KBD and 98 healthy controls. PCR-RFLP were performed to detect SNP loci of IL-1beta gene and DVWA gene. RESULTS: The patients with KBD had significantly higher frequency of rs16944 (IL-1beta) locus (chi2 = 24.28, P < 0.001) and single allele frequency of rs16944 (chi2 = 5.683, P = 0.0171) than the healthy controls. There were no significant differences in genotype frequencies,single allele frequencies and haplotypes in rs4685241 and rs1143627 between the patients with KBD and the healthy controls. CONCLUSION: rs16944 (IL-1beta) is associated with KBD.

[Genetic structure of X-STR loci in Bai, Dai and Yi ethnic groups and their affinity with five major populations of China].

To determine the genetic polymorphism of three X-STR loci for Bai, Dai, Yi ethnic groups from Yunnan Province, DXS6804, DXS6799 and DXS7132 were genotyped by multiplex PCR and Genscan. Eighteen alleles and thirty-eight genotypes were detected in 89 Bai unrelated persons. The gene frequencies ranged from 0.0200 to 0.6400, and the geno-types frequencies ranged from 0.0256 to 0.3333. Seventeen alleles and twenty-four genotypes were detected in 100 Dai unrelated persons, with the gene frequencies ranging from 0.0135 to 0.7500 and the genotypes frequencies ranging from 0.0385 to 0.5769 respectively. There were 20 alleles and 35 genotypes detected in 88 Yi unrelated persons. The gene frequencies ranged from 0.0125 to 0.5875, and the genotypes frequencies ranged from 0.0250 to 0.3500. The genetic information demonstrated that the three loci are highly polymorphisms in Bai, Dai, Yi ethnic groups. Cluster analysis and phylogenic tree showed the genetic affinity between Bai, Dai, Yi, and Tibet populations.

Cellular Inflammatory Response of the Spleen After Acute Spinal Cord Injury in Rat.

Spinal cord injury (SCI) involves both primary and secondary damages. After the phase of primary injury, a series of inflammatory responses initiate, which belong to the secondary injury. There has been little investigation into the cellular inflammatory response of the spleen to SCI. To disclose the impact of SCI on the spleen, we examined the inflammatory reactions of the spleen during the acute phase of SCI in rat. Adult rats were used as experimental animals and divided into un-injured, sham, and SCI groups (n = 36). Contusion injuries were produced at the T3 vertebral level. Spinal cords were harvested 6 h, 24 h, 48 h, 72 h, 120 h, and 168 h after surgery and were prepared for immunohistochemistry. Spleen wet weight was measured. Blood and spleens were prepared for quantitative analyses. The spleen index was significantly decreased in the SCI groups. Immunohistochemical results showed an increase of the infiltrating cells in the spinal cord tissues from SCI rats at all time points, peaking in 72 h post injury. In the blood, T and B lymphocytes significantly decreased in the SCI group as compared with the sham group, while monocyte increased. Surprisingly, in the SCI group, neutrophil initially decreased and subsequently tended to return toward baseline levels, then remained elevated until the end of the study. Spleen analyses revealed a significant increase in monocyte and neutrophil but a minor (not statistically significant) reduction in T and B lymphocytes. Our data show that the four most prevalent inflammatory cells infiltrate the spinal cord after injury. Increased levels of inflammatory cells (monocyte and neutrophil) in the blood and spleen appear to be very sensitive to SCI. The spleen plays a critical role in the acute phase of SCI.

Contents of Heavy Metals in Chinese Edible Herbs: Evidence from a Case Study of Epimedii Folium.

Toxic heavy metal contamination in Chinese edible herbs has raised a worldwide concern. In this study, heavy metals in Epimedii Folium, an edible medicinal plant in China, were quantitatively analyzed. Variations of heavy metals in different species, in various organs (i.e., leaves, stems, and roots), in wild-growing and cultivated plants, and in 35 market samples of Epimedii Folium, were systematically investigated. In all of Epimedium samples, Hg (mercury) was not detectable (0.00 µg/g). Four species, Epimedium pubescens, Epimedium sagittatum, Epimedium brevicornu, and Epimedium wushanense, were found to contain Cu (copper) and Pb (lead). And contents of Cu and Pb in E. brevicornu were significantly higher than those in other species (P < 0.01). In wild-growing and cultivated Epimedium plants, Cd (cadmium) and As (arsenic) were not detectable, and concentrations of Cu and Pb in wild-growing plants were significantly higher than those in cultivated plants (P < 0.01). Cd was not detectable in leaves, roots, and stems, while organ specificity was apparent in the distribution of Cu, As, and Pb. And the highest levels of Cu and Pb were observed in roots and leaves, respectively. In Chinese markets, several samples of Epimedii Folium contained excessive Cu, Cd, As, and Pb beyond the national permissible limits. In summary, there was a large variation of heavy metals among Epimedii Folium samples, and Cu and Pb were the most important heavy metals contaminating the edible medicinal plant. Application of Epimedii Folium to drug and food industries will need to focus more on toxic heavy metal contamination.

Expression of NG2 and platelet-derived growth factor receptor alpha in the developing neonatal rat brain.

Platelet-derived growth factor receptor alpha (PDGFRα) is a marker of oligodendrocyte precursor cells in the central nervous system. NG2 is also considered a marker of oligodendrocyte precursor cells. However, whether there are differences in the distribution and morphology of oligodendrocyte precursor cells labeled by NG2 or PDGFRα in the developing neonatal rat brain remains unclear. In this study, by immunohistochemical staining, NG2 positive (NG2+) cells were ubiquitous in the molecular layer, external pyramidal layer, internal pyramidal layer, and polymorphic layer of the cerebral cortex, and corpus callosum, external capsule, piriform cortex, and medial septal nucleus. NG2+ cells were stellate or fusiform in shape with long processes that were progressively decreased and shortened over the course of brain development. The distribution and morphology of PDGFRα positive (PDGFRα+) cells were coincident with NG2+ cells. The colocalization of NG2 and PDGFRα in the cell bodies and processes of some cells was confirmed by double immunofluorescence labeling. Moreover, cells double-labeled for NG2 and PDGFRα were predominantly in the early postnatal stage of development. The numbers of NG2+/PDGFRα+ cells and PDGFRα+ cells decreased, but the number of NG2+ cells increased from postnatal days 3 to 14 in the developing brain. In addition, amoeboid microglial cells of the corpus callosum, newborn brain macrophages in the normal developing brain, did not express NG2 or PDGFRα, but NG2 expression was detected in amoeboid microglia after hypoxia. The present results suggest that NG2 and PDGFRα are specific markers of oligodendrocyte precursor cells at different stages during early development. Additionally, the NG2 protein is involved in inflammatory and pathological processes of amoeboid microglial cells.

[The genetic polymorphism of 9 short tandem repeat loci in Yi ethnic group of Yunnan in China].

OBJECTIVE: To study the short teadem repeat(STR) genetics structure of a Chinese Yunnan Yi racial group. METHODS: Genetic distributions for nine STR loci were determined based on STR gene scan marked by fluorescence. RESULTS: Sixty-nine alleles and 164 kinds of genotypes were detected and identified from 84 unrelated Yi racial individuals. The corresponding gene and genotype frequencies were in 0.0060-0.5060 or 0.0119-0.4167 respectively. The expected and observed genotype frequencies of nine STR loci were in accordance with the Hardy-Weinberg equilibrium(P>0.05). The statistical analyses of nine STR loci showed that PIC was distributed in 0.5804-0.8777, H was in 0.6507-0.8002, DP was in 0.7976-0.9558, EPP was in 0.5207-0.8386, except TPOX and THO1 loci. CONCLUSION: Above research data enrich the Chinese genetic database, and play an important role in Chinese genetic study and in forensic application.

[Genetic polymorphisms and application of 9 STR loci of 5 ethnic groups in Gansu and Qinghai].

OBJECTIVE: To examine the genetic polymorphism of 9 STR loci in 5 ethnic groups (including Tu, Sala, Dongxiang, Baoan and Yugu) in Gansu and Qinghai, and to evaluate its application. METHODS: Nine STR loci (D3S1358, FGA, TH01, D7S820, VWA, CSF1PO, D5S818, D13S317 and TPOX) were selected as genetic markers. With STR compound amplification and genescan methods, in which STR loci were marked by fluorescence, the genotype of 5 ethnic groups were examined in 606 unrelated individuals by ABI 377 sequencer. These parameters, such as polymorphism information content (PIC), heterozygosity (H), discrimination power (DP) and probability of paternity exclusion (PPE) were calculated. RESULTS: The genotype frequencies of the 9 STR loci were in accordance with Hardy-Weinberg equilibrium. PIC was within 0.6054 - 0.8735, H was within 0.6158 - 0.8736, DP was within 0.7964 - 0.9691, and PPE was within 0.4610 - 0.8838. Cluster analysis based on allele frequencies in genesis showed Tu, Sala, Dongxiang and Baoan ethnic groups were very close, but Yugu was a little bit far. There were obvious gene exchanges among the populations in north and south of China. CONCLUSION: All the 9 STR loci are highly polymorphic in the 5 ethnic groups, which can be useful genetic markers in forensic medicine and population genetics.

[Analysis on HLA haplotypes of loci HLA-A, -B, and -DRB1 in northwest Chinese Han population].

OBJECTIVE: To investigate HLA-A, -B and -DRB1 allele and HLA-A-B, B-DRB1, A-B-DRB1 haplotype frequencies in the northwest Chinese Han population. METHODS: The authors investigated the HLA-A, -B, -DRB1 allele and haplotype in a northwest Chinese Han population based on 62 families and 101 individuals by use of PCR-sequence specific oligonucleotide probes(PCR-SSOP) DNA typing methods. RESULTS: Fifteen alleles for the locus HLA-A, 28 alleles for the HLA-B locus and 13 alleles for the HLA-DRB1 were detected. The results showed that the most frequent HLA alleles found were A02 (0.3244), B13 (0.1200), and DRB1*15 (0.1400). Allele frequencies of more than 10% for HLA antigens were A02, A11, A24, B13, B15, B40, DRB1*04, DRB1*07, DRB1*09, DRB1*15. In the analysis of HLA haplotypes, 122 kinds of HLA-A-B haplotypes and 147 kinds HLA-B-DRB1 haplotypes were found. Two hundred and seventy-eight kinds of HLA-A-B-DRB1 haplotypes were found, comprising 61.78%(278/450) of total theoretical haplotypes. Eighty-three kinds of HLA-A-B-DRB1 haplotypes were shown to have at least two same haplotypes, comprising 18.44%(83/450) of total theoretical haplotypes. The most common HLA-A-B-DRB1 haplotypes were A30-B13-DRB1*07, A02-B46-DRB1*09, A01-B37-DRB1*10, A24-B15-DRB1*15, A02-B46-DRB1*08, A33-B58-DRB1*03. CONCLUSION: The data can be used for the estimation of the probability of finding haplotypically identical, related or unrelated bone marrow donor for an individual patient, and forensic and paternity tests to estimate the frequency of a DNA profile or anthropologic research.

[Analysis of genetic polymorphism of 7 STR loci on chromosome 12 in Shaanxi Han populations].

To analyze the genetic polymorphism of 7 STR loci (D12S1718,D12S1675, D12S358, D12S367, D12S1638, D12S1646 and D12S1682) on chromosome 12 in Shaanxi Hans. EDTA-blood specimens were collected from 80 unrelated individuals from Chinese Han population in Shaanxi province. The DNA samples were extracted and relevant fragments were amplified by polymerase chain reaction (PCR). The PCR products were analyzed by ABI 3100 Genetic Analyzer. The number of alleles and genotypes observed at loci D12S1718, D12S1675, D12S358, D12S367, D12S1638, D12S1646 and D12S1682 were 7, 10, 8, 8, 6, 9, 11 for alleles and 10, 17, 18, 18, 14, 18, and 26 for genotypes, respectively. The heterozygosities for the 7 STR loci were 44.28%, 66.10%, 78.89%, 77.89%, 73.69%, 74.55% and 82.39%, respectively. The distribution of allele frequencies of 7 STR loci on chromosome 12 was consistent with Hardy-Weinberg equilibrium and relatively high genetic polymorphism was observed in Shaanxi Han population.

[STR polymorphisms in four Xinjiang ethnic groups in China].

Population genetic studies were performed in Xinjiang's Uygur, Sibe, Ozbek and Kirgiz. Allele frequency distributions were analyzed for ten loci, i.e., D3S1358, VWA, CSF1PO, FGA, THO1, TPOX, D5S818, D13S317 and D7S820 by GeneScan. The results showed that there were 66 STR alleles and 148 genotypes in Uygur; 72 STR alleles and 163 genotypes in Sibe; 65 STR alleles and 168 genotypes in Ozbek; 71 STR alleles and 191 genotypes in Kirgiz. Significant differences were identified among ethnic groups (African-American, US-Caucasian and Chinese-Oriental), but similarity was found among the four Xinjiang population. These findings indicated that the nine STR loci and Amelogenin locus were very useful for individual identification in forensic science. It is further certified that Chinese nationality is a whole.

Analysis of DNA polymorphism at HLA-A locus by PCR amplification with sequence specific oligonucleotide probe in Chinese Han and Uygur populations.

To determine HLA-A genetic polymorphism in Chinese populations and establish ethnic genetic database, 165 Han and 162 Uygur subjects were investigated with a non-isotopic and sensitive method PCR-SSOP. 22 alleles were identified in Han with the most frequent allele being HLA-A * 1101 (19.7%), followed by * 0201 (12.72%). Also, 22 alleles were identified in Uygur with * 2407 (17.90%) being the most frequent one and the frequencies of following alleles: * 0201, * 0101, * 3301 were higher than 10%. HLA-A * 0203, * 0205, * 0210, * 0302, * 2403 and * 3302 were only detected in Han; meanwhile * 0205, * 0211, * 2301, * 2502, * 68012 and * 6802 were only in Uygur. According to Hardy-Weinberg equilibrium, each allele showed no significant (P > 0.05) deviation between the expected frequency and the observed one. Heterozygosity (H), discrimination power (DP) and probability of paternity exclusion (EPP) of HLA-A locus from Han nationality were computed to be 0.9029, 0.9776 and 0.8592; and those from Uygur as 0.9063, 0.9379 and 0.7885. These results suggest that HLA-A DNA polymorphism and the database of two Chinese populations have useful applications in processing forensic casework (as personal identification, paternity test), tracing population migration and genetic diagnosis.

[Genetic structure of STR in Naci ethnic group in China].

STR is a universal genetic marker that has changeable polymorphism and stable heredity in human genome. It is a specific DNA segment composed of 2-7 base pairs as its core sequence, and is formed through the repeated connection of the same one. Since it has the characteristics such as numerous allelic genes, highly heterozygosity and easy recognition and short PCR segment, it is employed as an ideal DNA marker in such practical fields as human genetics and forensic medicine. In this study, we investigated the polymorphism of STR of Naci minority with STR genescan marked by fluorescence. Seventy-two alleles of 9 STR in Naci were detected with their frequency 0.0052-0.5208 and 165 genotypes were found out with frequency 0.0104-0.3021. Hi-Square test indicated the distribution of genotypes agreed with Hardy-Weinberg equilibrium (P > 0.05). Statistical analysis showed the followings: the heterozygosity (H) > 0.6 in each locus, the average polymorphism information content (PIC) > 0.7, Mean discrimination power (DP) > 0.8, probability of paternity exclusion (EPP) > 0.5, indicating that the STR markers used in the study were of great value in the researches of minority genetics. This not only founds the base for genetic structures of STR of Chinese but also provides valuable information for anthropology, forensic medicine and ethnology.

[Studies of STR polymorphisms in Pumi and Lisu minorities in China].

In this study, we investigated the polymorphisms of STR of Pumi and Lisu minorities with STR genescan marked by fluorescence. Eighty-five alleles of 9 STR in Pumi were detected with the frequency 0.0050-0.5250 and 194 genotypes were found with frequency of 0.0098-0.3235. Sixty three alleles with their frequency of 0.0050-0.4802 and 145 genotypes were found out with frequency of 0.0099-0.3664 in Lisu population. Hi-Square test indicated the distribution of genotypes agreed with Hardy-Weinberg equilibrium (P > 0.05). Statistical analysis showed the followings: H > 0.6 in each locus, the average PIC > 0.7, mean DP > 0.8, EPP > 0.5, indicating the STR markers used in the study were of great value in the researches on minority genetics.

[Genetic polymorphism of 9 STR loci in Zhuang national minority of China].

Genetic distribution for nine STR loci were determined in a Chinese Guangxi Zhuang national minority group based on STR gene scan marked by fluorescence. Sixty-two alleles and 169 genotypes were observed in 91 unrelated Zhuang individuals. The corresponding gene frequency and genotype frequency were 0.0054-0.5495 and 0.0110-0.3297 respectively. The expected and observed genotype frequency of nine STR loci was in accordance with the Hardy-Weinberg equilibrium (P > 0.05). The statistical analysis of nine STR loci showed PIC (polymorphic information content) > or = 0.6088, H (heterozygosity) > or = 0.6174, DP (discrimination power) > or = 0.8028, PPE (probability of paternity exclusion) > or = 0.8165. The genetic distance figured with 9 STR genetic data showed that there were significant differences between Chinese Zhuang national minority and the American White and the American Black, and there was little difference between Zhuang national minority and the Chinese Xi'an Han. The result of clusting showed that the present data were divided into three groups: the Black, the White and the Yellow (the Chinese).

[Study on 9 STR loci polymorphism from Chinese Yao ethnic group(Guangxi)].

Genetic polymorphism of nine STR loci was investigated from a Chinese Yao population based on STR Genescan. Sixty one alleles was determined for 9 loci, such as D3S1358,vWA,FGA,THO1,TPOX,CSF1P0,D5S818,D13S317 and D7S820 with their frequencies 0.0054-0.5924. The average heterozygosity(H) was 0.7357, polymorphism information content(PIC) was 0.6887, the accumulative discrimination power(DP) was 2.02x10(-10) and the probability of paternity exclusion(PPE) was 0.9999. These results suggested that the nine STR loci are very useful for human identification, such as analyzing forensic casework,establishing DNA databases, processing paternity test and studying gene natural resources.

[Polymorphism of nine STR locus in Nu population from Yunnan Province].

In this study,blood samples were randomly drawn from 84 unrelated Nu individuals. The polymorphism of nine STR loci and Amelogenin locus were determined by DNA GeneScan. The genetic database on the distribution of gene frequency on the nine STR loci was established, statistical results showed that the genotype distributions were in agreement with Hardy-Weinberg equation. Compared with other population,the results in our study were of great value in human DNA genetic data instant method with the characteristics of precision and sensitivity.

[Genetic polymorphism of 9 STR loci in Chaoxian National Minority of China].

In order to enrich the Chinese genetic database,nine polymorphic loci of STR,such as D3S1358,vWA,FGA,TH01,TPOX,CSF1PO,D5S818,D13S317 and D7S820 were studied. Based on STR gene scan marked by fluorescence,91 unrelated Chinese Chaoxian individuals were observed.81 alleles and 196 genotypes were found. The corresponding gene frequency and genotype frequency were 0.0055-0.4615 and 0.0110-0.9890 respectively. The genogypes frequency of nine STR loci was good with the Hardy-Weinberg equilibrium (P approximately 0.05). The statistical analysis of nine STR loci showed the following: PIC (polymorphic information content) >or=0.6863, H (heterozygosity) >or=0.6919, DP (discrimination power) >or=0.8301, EPP (probability of paternity exclusion) >or=0.8590. The data studied can be used in Chinese population genetic studies and forensic medicine applications.