Search

In recent years, the increase in the number of cases of postural asphyxia has gradually attracted the attention and discussion of forensic scientists domestically and internationally, but a systematic, comprehensive and recognized expert consensus and identification standard has not been established at home and abroad. This paper reviews the case characteristics, occurrence, mechanism of death, and identification criteria of postural asphyxia, to provide reference for future research.

Ligand fishing is a promising strategy for the screening of active ingredients from complex natural products. In this work, human tyrosinase (hTYR) was displayed on the surface of Chinese hamster ovary (CHO) cells for the first time; it was then used as bait to develop a new method for ligand fishing. The localization of hTYR on the CHO cell surface was verified by an enzyme activity test and fluorescence microscopy. The displayed tyrosinase (CHO@hTYR) maintained relatively stable enzymatic activity (82.59 ± 2.70%) within 7 days. Furthermore, it can be reused for fishing five times. Guided by the proposed ligand fishing method, four tyrosinase inhibitors, including 4-methoxy-5-methyl coumarin (1), cupressuflavone (2), amentoflavone (3), and 3,4-dimethoxy-5-methyl coumarin (4), were isolated from Alhagi sparsifolia, and the active fraction with low polarity was isolated from Coffea arabica; these two medicinal plants possess skin-lightening potential. All the isolated tyrosinase inhibitors significantly reduced the intracellular tyrosinase activity and melanin level in B16 cells enhanced by α-MSH. Meanwhile, the active fraction (100 μg/mL) from C. arabica exhibited stronger inhibitory effects than the positive controls (α-arbutin and kojic acid) by recovering them to the normal levels. This work demonstrated the promising application of the cell surface display in the field of ligand fishing and is helpful in unveiling the chemical basis of the skin-lightening effect of A. sparsifolia and C. arabica. [ABSTRACT FROM AUTHOR]

Coreopsis tinctoria Nutt. is an important medicinal plant in traditional Uyghur medicine. The skin-lightening potential of the flower has been recognized recently; however, the active compounds responsible for that are not clear. In this work, tyrosinase, a target protein for regulating melanin synthesis, was immobilized on the Whatman paper for the first time to screen skin-lightening compounds present in the flower. Quercetagetin-7-O-glucoside (1), marein (2), and okanin (3) were found to be the enzyme inhibitors. The IC50 values of quercetagetin-7-O-glucoside (1) and okanin (3) were 79.06 ± 1.08 μM and 30.25 ± 1.11 μM, respectively, which is smaller than 100.21 ± 0.11 μM of the positive control kojic acid. Enzyme kinetic analysis and molecular docking were carried out to investigate their inhibition mechanism. Although marein (2) showed a weak inhibition effect in vitro, it inhibited the intracellular tyrosinase activity and diminished melanin production in melanoma B16 cells as did the other two inhibitors. The paper-based ligand fishing method developed in this work makes it effective to quickly screen tyrosinase inhibitors from natural products. This is the first report on the tyrosinase inhibitory effect of those three compounds, showing the promising potential of Coreopsis tinctoria for the development of herbal skin-lightening products. [ABSTRACT FROM AUTHOR]

Objective To study the relationship between material mechanics and bone material parameters of rat skulls and their correlation with age by examination of the parameters. Methods Forty-eight healthy male SD rats were divided into 2, 4, 6, 8, 17, 26, 52 and 104 week groups according to their age. Each group had six rats. The right cranium was compressed by KD Ⅱ-0.2 microcomputer controlled electronic universal testing machine, and material mechanics parameters （ultimate load, compression strength and compression modulus） were measured, then the skull slices were cut off and scanned by Micro-CT system to detect bone material parameters （skull thickness, bone mineral density, bone volume, and trabecular thickness）. Results The differences in ultimate load, compression strength and compression modulus among all groups had statistical significance （P

Objective To study the relations of the dural thickness and the biomechanical parameters with postmortem interval （PMI） of human cadavers, and to explore the feasibility of the two indexes used for PMI estimation. Methods Dural samples were collected at different postmortem intervals of 6 h, 12 h, 18 h, 24 h, 30 h, 36 h, 48 h, 60 h, 72 h, 84 h and 96 h, then fabricated into 4.0 cm×1.0 cm A and B test specimens. The thickness of the A test specimen was measured, and the biomechanical parameters, such as ultimate load, maximum force deformation, tensile strength, elastic modulus and fracture force, were measured. The regression equations of thickness, biomechanical parameters and PMI were fitted respectively, and the difference between the predicted value and actual measured value of PMI was verified by the verification group. The B test specimen was fixed with 10% neutral formaldehyde solution, then tissue sections were prepared to observe its morphological changes. Results From 6 h to 96 h after death, the dural thickness decreased gradually, the collagen fibers gradually changed from clear arrangement to mutual fusion, and the number of nuclei decreased gradually. The dural thickness, ultimate load, tensile strength, elastic modulus and fracture force decreased sequentially, among which the dural thickness, ultimate load, elastic modulus and fracture force had a correlation with PMI （P0.05）. Conclusion The dural thickness, ultimate load, elastic modulus and fracture force change sequentially from 6 h to 96 h after death. The regression equation established by the relationship between the changes and PMI can be used for PMI estimation.

AIM:To compare dry eye symptoms and signs before and after three kinds surgery, femtosecond laser-assisted laser in situ keratomileusis(FS-LASIK), transepithelial photorefractive keratectomy(T-PRK), small incision lenticule extraction(SMILE)using ocular surface analyzer(Oculus Keratograph). METHODS:Totally 98 patients(196 eyes)undergoing corneal refractive surgery from January 2017 to May 2017 were recruited. They were divided into three groups, namely, FS-LASIK group, T-PRK group and SMILE group. All patients underwent observation and assessment in the following order: ocular surface disease index(OSDI), tear meniscus height(TMH), measure using the infrared pattern of Oculus Keratograph. The first tear film break-up time(FBUT)and average tear break-up time(ABUT)measure using the infrared pattern of Oculus Keratograph, corneal fluorescein staining(FL), Schirmer Ⅰ test(SⅠt). RESULTS:1)OSDI index: There was statistically significant difference between the three groups(Fgroups=2.799, PgroupsFtime=85.942, PtimeP=0.019), and the OSDI values of the T-PRK group were higher than those of the other two groups. 2)TMH: There was statistically significant difference among the three groups postoperatively(Fgroups=1.720, PgroupsFtime=11.202, PtimeP=0.004), and the inferior TMH in the SMILE group was higher than that of the other two groups. 3)FBUT: There was statistically significant difference among the three groups after surgery(Fgroups=1.428, Pgroups=0.245). The difference in FBUT values between different time points in each group was statistically significant(Ftime=4.511, Ptime=0.001). The FBUT values of each group were significantly reduced after 1wk and 1mo, and recovered to preoperative levels after 3mo and 6mo. There was no significant difference in FBUT between different groups at each time points(P>0.05). 4)ABUT: There was statistically significant difference in ABUT among the three groups after surgery(Fgroups=1.290, PgroupsFtime=10.294, PtimeP=0.008); among them, the ABUT value of the SMILE group was higher than that of the T-PRK group and the FS-LASIK group. 5)FL: There was no statistical difference in the FL score between the three groups(Fgroups=0.816, Pgroups=0.445). The differences in the FL scores at different points in each group were statistically significant(Ftime=5.539, Ptime=0.004). The FL score of each group was significantly higher than before surgery at 1wk and 1mo, and recovered to preoperative levels at 3mo and 6mo after surgery. There was no statistical difference in the FLs between different groups at different points in time(P>0.05). 6)SⅠt: There was no statistically significant difference in SⅠt values among the three groups after surgery(Fgroups=0.225, Pgroups=0.799). The difference in SⅠt values between different time points in each group was statistically significant(Ftime=4.604, Ptime=0.003). The SⅠt values of each group were slightly higher than the preoperative values afyer 1wk and 3mo, but they were all within normal values. There was no significant difference between the SⅠt values of 1mo or 6mo after operation and the preoperative level. There was no statistical difference in SⅠt values between different groups at each points in time(P>0.05).CONCLUSION:The three types of corneal refractive surgery FS-LASIK, T-PRK, and SMILE all cause different degrees of dry eyes within a certain period of time after surgery, but they can gradually recover later. After SMILE surgery, the stability of the tear film recovered faster, while the symptoms after T-PRK surgery improved the least.

This research utilized single‐cell RNA sequencing to map the immune cell landscape in sepsis, revealing 28 distinct cell clusters and categorizing them into nine major types. Delving into the monocyte/macrophage subclusters, 12 unique subclusters are identified and pathway enrichment analyses are conducted using KEGG and GO, discovering enriched pathways such as oxidative phosphorylation and antigen processing. Further GSVA and AUCell assessments show varied activation of interferon pathways, especially in subclusters 4 and 11. The clinical correlation analysis reveals genes significantly linked to survival outcomes. Additionally, cellular differentiation in these subclusters is explored. Building on these insights, the differential gene expression within these subclusters is specifically scrutinized, which reveal MYOF as a key gene with elevated expression levels in the survivor group. This finding is further supported by in‐depth pathway enrichment analysis and the examination of cellular differentiation trajectories, where MYOF's role became evident in the context of immune response regulation and sepsis progression. Validating the role of the MYOF gene in sepsis, a dose‐dependent response to LPS in THP‐1 cells and C57 mice is observed. Finally, inter‐cellular communications are analyzed, particularly focusing on the MYOF+Mono/Macro subcluster, which indicates a pivotal role in immune regulation and potential therapeutic targeting. [ABSTRACT FROM AUTHOR]