Objective:To investigate abnormal blood lipids of military flying personnel and related contributors in order to provide data for health support to military flying personnel.Methods:The physical examination data of 358 military flying personnel between November 2022 and April 2023 was retrospectively analyzed. The flying personnel were divided into 3 groups by age (20-≤29 years, 30-≤39 years and ≥40 years), 3 groups by aircraft types (helicopters, fighters and trainers), 2 groups by flying hours (≤2 000 h and >2 000 h) and 2 groups by body mass index (<24.0 kg/m 2 and ≥24.0 kg/m 2). The blood lipid abnormalities of these military flying personnel were compared across groups. Results:There was a significant difference in levels of total cholesterol ( F=3.77, P=0.024), triglyceride ( H=12.10, P=0.002) and low-density lipoprotein cholesterol ( F=5.61, P=0.004) across age groups, but there was no significant difference in levels of high-density lipoprotein cholesterol ( P>0.05). There was no significant difference in levels of total cholesterol, triglyceride, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol between military flying personnel working for different types of aircraft (all P>0.05). Levels of total cholesterol ( F=8.69, P=0.003), triglyceride ( Z=2.57, P=0.010) and high-density lipoprotein cholesterol ( F=10.61, P=0.001) in the >2 000 h group were significantly higher than those in the ≤2 000 h group. There was no significant difference in levels of low-density lipoprotein cholesterol between groups of different flying hours ( P>0.05). The levels of total cholesterol ( F=10.39, P=0.002), triglyceride ( Z=4.05, P<0.001) and low-density lipoprotein cholesterol ( F=12.73, P<0.001) in the body mass index ≥24 kg/m 2 group were significantly higher than those in the body mass index <24 kg/m 2 group. There was no significant difference in levels of high-density lipoprotein cholesterol between different body mass index groups ( P>0.05). Conclusions:There were differences in the blood lipid abnormality among military flying personnel with different ages, flying hours and body mass index. It is critical to better manage the blood lipid indicators of flying personnel, provide early intervention and treatment, improve the rate of normal blood lipids, and ensure the health of flying personnel.

Objective:To investigate the effects of different post space parameters and scanning aid material on the trueness of digital impressions of post spaces obtained by two intraoral scanners, thereby providing a reference for clinically determining the conditions under which post spaces are suitable for digital impression technology.Methods:This study varied three variables of post space models of residual crowns: opening diameter, post space depth and adjacent tooth status,with specific settings: opening diameter were set at two levels (2.0 and 2.5 mm);post space depth was set at three levels (8.0, 10.0, and 12.0 mm); and adjacent tooth status were set at three levels [bilateral adjacent teeth present (A), unilateral adjacent tooth present (B), and bilateral adjacent teeth absent (C)]. A total of 18 model groups were prepared. Eighteen samples were printed using a three-dimensional printing instrument. Combined with scanning aid material, direct in vitro scanning of these post space models was performed using intraoral scanners (IOS) A (Trios 5) and B (Primescan connect), with 10 replicates per group ( n=10). The scanned data were sequentially imported into reverse engineering software. The original design data of the models served as true values, and best-fit comparisons were performed. By calculating the average root mean square error (RMSE) values, the trueness of digital impressions of post spaces with different morphologies obtained by the two scanners was evaluated, both with and without the use of scanning aid material. Results:Under the experimental conditions set in this study, for IOS A, only the sample groups with opening diameter-post space depth-adjacent tooth status combinations of (2.0-8.0-ABC, 2.5-8.0-ABC, 2.5-10.0-ABC) could be identified, with RMSE results ranging from 46.5 to 365.0 μm. After adding scanning aid materials,RMSE results ranging from 46.0 to 185.0 μm, the trueness of the sample groups (2.0-8.0-A, 2.5-10.0-A) was significantly improved by more than 100 μm, and an additional sample group (2.5-12.0-C) could be identified. For IOS B, the identifiable sample groups included all 18 sample groups, with RMSE results ranging from 38.8 to 106.0 μm. After the addition of scanning aid materials, RMSE results ranging from 37.6 to 110.2 μm, the identifiable sample groups remained unchanged. Post space opening diameter, post space depth, and adjacent tooth status all had significant effects on the trueness of post space digital impressions for both IOS A and IOS B (all P<0.05). Scanning aid materials had a significant effect on IOS A ( P<0.05), but no significant effect on IOS B ( P>0.05). Conclusions:IOS B exhibited superior post space scanning performance compared to IOS A, and its trueness for clinically common post spaces could meet clinical requirements. IOS A has certain requirements for post space opening diameter, post space depth, and adjacent tooth status. For narrow and long post spaces, scanning aid materials can be used to improve the scanning trueness.

Objective:To anatomically and phenotypically characterize the insular cortex(IC)-nucleus tractus soli-tarii(NTS)neural pathway.Methods:Adult male Sprague-Dawley rats were divided into three experimental cohorts for neural circuit tracing.Anterograde labeling was achieved by injecting anterograde self-complementary adeno-associated viruses(scAAVs)into the IC.Retrograde tracing involved NTS injections of either retrograde scAAVs or FluoroGold(FG),combined with immunofluorescence histochemical staining to identify IC-originating projection neurons.For postsynaptic neurochemical phenotype characterization,IC was injected with AAV2/1-CaMKII-Cre,while a mixture of AAV2/9-Syn-DIO-mCherry and AAV2/9-VGAT1-EGFP was injected into the NTS.The rats were allowed to survive for one week following scAAVs or FG injection or four weeks after recombinase-dependent systems injection.Then the rats were sacrificed,and serial brain sections were prepared for immunofluorescence histochemical staining(brain section containing FG)and subsequent fluorescence/confocal microscopic analysis.Results:(1)Anterograde viral tracing re-vealed dense axonal terminals from the IC projecting to the medial subnucleus of the NTS,while retrograde tracing re-vealed that IC neurons projecting to the NTS were predominantly localized within the dysgranular layer;(2)IC-NTS projection neurons were exclusive glutamatergic(100%,n=3);(3)NTS neurons receiving IC inputs were mainly lo-calized in the medial subnucleus,and were predominantly GABAergic(79.8±3.2%,n=3).Conclusion:The pres-ent results indicate that a descending pathway from excitatory neurons of the IC terminates onto inhibitory neurons of the NTS,which might represent a potential neuromodulatory target for visceral pain disorders.

Objective:To investigate the effects of different post space parameters and scanning aid material on the trueness of digital impressions of post spaces obtained by two intraoral scanners, thereby providing a reference for clinically determining the conditions under which post spaces are suitable for digital impression technology.Methods:This study varied three variables of post space models of residual crowns: opening diameter, post space depth and adjacent tooth status,with specific settings: opening diameter were set at two levels (2.0 and 2.5 mm);post space depth was set at three levels (8.0, 10.0, and 12.0 mm); and adjacent tooth status were set at three levels [bilateral adjacent teeth present (A), unilateral adjacent tooth present (B), and bilateral adjacent teeth absent (C)]. A total of 18 model groups were prepared. Eighteen samples were printed using a three-dimensional printing instrument. Combined with scanning aid material, direct in vitro scanning of these post space models was performed using intraoral scanners (IOS) A (Trios 5) and B (Primescan connect), with 10 replicates per group ( n=10). The scanned data were sequentially imported into reverse engineering software. The original design data of the models served as true values, and best-fit comparisons were performed. By calculating the average root mean square error (RMSE) values, the trueness of digital impressions of post spaces with different morphologies obtained by the two scanners was evaluated, both with and without the use of scanning aid material. Results:Under the experimental conditions set in this study, for IOS A, only the sample groups with opening diameter-post space depth-adjacent tooth status combinations of (2.0-8.0-ABC, 2.5-8.0-ABC, 2.5-10.0-ABC) could be identified, with RMSE results ranging from 46.5 to 365.0 μm. After adding scanning aid materials,RMSE results ranging from 46.0 to 185.0 μm, the trueness of the sample groups (2.0-8.0-A, 2.5-10.0-A) was significantly improved by more than 100 μm, and an additional sample group (2.5-12.0-C) could be identified. For IOS B, the identifiable sample groups included all 18 sample groups, with RMSE results ranging from 38.8 to 106.0 μm. After the addition of scanning aid materials, RMSE results ranging from 37.6 to 110.2 μm, the identifiable sample groups remained unchanged. Post space opening diameter, post space depth, and adjacent tooth status all had significant effects on the trueness of post space digital impressions for both IOS A and IOS B (all P<0.05). Scanning aid materials had a significant effect on IOS A ( P<0.05), but no significant effect on IOS B ( P>0.05). Conclusions:IOS B exhibited superior post space scanning performance compared to IOS A, and its trueness for clinically common post spaces could meet clinical requirements. IOS A has certain requirements for post space opening diameter, post space depth, and adjacent tooth status. For narrow and long post spaces, scanning aid materials can be used to improve the scanning trueness.

Objective:To anatomically and phenotypically characterize the insular cortex(IC)-nucleus tractus soli-tarii(NTS)neural pathway.Methods:Adult male Sprague-Dawley rats were divided into three experimental cohorts for neural circuit tracing.Anterograde labeling was achieved by injecting anterograde self-complementary adeno-associated viruses(scAAVs)into the IC.Retrograde tracing involved NTS injections of either retrograde scAAVs or FluoroGold(FG),combined with immunofluorescence histochemical staining to identify IC-originating projection neurons.For postsynaptic neurochemical phenotype characterization,IC was injected with AAV2/1-CaMKII-Cre,while a mixture of AAV2/9-Syn-DIO-mCherry and AAV2/9-VGAT1-EGFP was injected into the NTS.The rats were allowed to survive for one week following scAAVs or FG injection or four weeks after recombinase-dependent systems injection.Then the rats were sacrificed,and serial brain sections were prepared for immunofluorescence histochemical staining(brain section containing FG)and subsequent fluorescence/confocal microscopic analysis.Results:(1)Anterograde viral tracing re-vealed dense axonal terminals from the IC projecting to the medial subnucleus of the NTS,while retrograde tracing re-vealed that IC neurons projecting to the NTS were predominantly localized within the dysgranular layer;(2)IC-NTS projection neurons were exclusive glutamatergic(100%,n=3);(3)NTS neurons receiving IC inputs were mainly lo-calized in the medial subnucleus,and were predominantly GABAergic(79.8±3.2%,n=3).Conclusion:The pres-ent results indicate that a descending pathway from excitatory neurons of the IC terminates onto inhibitory neurons of the NTS,which might represent a potential neuromodulatory target for visceral pain disorders.

Objective:To investigate abnormal blood lipids of military flying personnel and related contributors in order to provide data for health support to military flying personnel.Methods:The physical examination data of 358 military flying personnel between November 2022 and April 2023 was retrospectively analyzed. The flying personnel were divided into 3 groups by age (20-≤29 years, 30-≤39 years and ≥40 years), 3 groups by aircraft types (helicopters, fighters and trainers), 2 groups by flying hours (≤2 000 h and >2 000 h) and 2 groups by body mass index (<24.0 kg/m 2 and ≥24.0 kg/m 2). The blood lipid abnormalities of these military flying personnel were compared across groups. Results:There was a significant difference in levels of total cholesterol ( F=3.77, P=0.024), triglyceride ( H=12.10, P=0.002) and low-density lipoprotein cholesterol ( F=5.61, P=0.004) across age groups, but there was no significant difference in levels of high-density lipoprotein cholesterol ( P>0.05). There was no significant difference in levels of total cholesterol, triglyceride, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol between military flying personnel working for different types of aircraft (all P>0.05). Levels of total cholesterol ( F=8.69, P=0.003), triglyceride ( Z=2.57, P=0.010) and high-density lipoprotein cholesterol ( F=10.61, P=0.001) in the >2 000 h group were significantly higher than those in the ≤2 000 h group. There was no significant difference in levels of low-density lipoprotein cholesterol between groups of different flying hours ( P>0.05). The levels of total cholesterol ( F=10.39, P=0.002), triglyceride ( Z=4.05, P<0.001) and low-density lipoprotein cholesterol ( F=12.73, P<0.001) in the body mass index ≥24 kg/m 2 group were significantly higher than those in the body mass index <24 kg/m 2 group. There was no significant difference in levels of high-density lipoprotein cholesterol between different body mass index groups ( P>0.05). Conclusions:There were differences in the blood lipid abnormality among military flying personnel with different ages, flying hours and body mass index. It is critical to better manage the blood lipid indicators of flying personnel, provide early intervention and treatment, improve the rate of normal blood lipids, and ensure the health of flying personnel.

Objective To explore the mechanism of microRNA (miRNA, miR)-155 in the rejection after liver transplantation in rats. Methods The rats were divided into two groups. In the xenograft model group (rejection group, n=10),the donors were male Lewis rats and the recipients were male BN rats.In the allograft model group(control group, n=10),both the donors and recipients were male Lewis rats.The rat models with orthotopic liver transplantation were established by two-cuff technique in two groups. At postoperative 7 d, the animals were sacrificed for the collection of blood and liver tissue samples. The serum levels of alanine aminotransferase (ALT), total bilirubin (TB), and cytokines of interleukin (IL)-2, IL-4, interferon (IFN)-γ were quantitatively measured. The pathological changes of liver tissues were observed under light microscope. In each group, three liver tissue samples were prepared and subject to high-throughput sequencing. The miRNAs related to rejection were identified for bioinformatics analysis to predict and analyze relevant signaling pathways and genes. Results In the rejection group, the serum levels of ALT and TB were significantly higher than those in the control group (both P<0.01). Compared with the control group, the levels of IL-2 and IFN-γ were considerably up-regulated (both P<0.01), whereas the level of IL-4 was dramatically down-regulated (P<0.01). Pathological examination demonstrated that more evident rejections were observed in the rejection group than the control group. High-throughput sequencing revealed that the expression level of miR-155 was significantly up-regulated in the rejection group, which was 5.89 times of that in the control group. Bioinformatics analysis demonstrated that up-regulation of miR-155 was associated with the mammalian target of rapamycin (mTOR), mitogen-activated protein kinase (MAPK) and T cell receptor signaling pathways. The genes which were probably responsible for regulation included the yeast autophagy related gene 1(ATG1) and its homologous gene ULK2, insulin-like growth factor-1 (Igf-1) and G protein-coupled receptor regulatory gene(Arrb1),etc.Conclusions miR-155 might promote the incidence and progression of rejection after liver transplantation in rats. The involved signaling pathways probably include the mTOR, MAPK signaling pathway and T cell receptor signaling pathway.ATG1,ULK2,Igf-1,and Arrb1 genes may participate in this process.