Objective: To observe the cellular damage of low-dose combined exposure to Hg, Pb and Cd on hippocampal neurons in rat. Methods: SH-SY5Y cells were randomly divided into 8 groups by 2×2×2 factorial design: control group, Pb exposure group, Hg exposure group, Pb+Hg exposure group, Pb+Cd exposure group, Hg+Cd exposure group and Pb+Cd+Hg exposure group. And the cell viabilities were measured. On this basis, an animal model was established. Twenty eight-week-old SD pregnant rats were randomly divided into four groups by random number table, and five in each group: the control group(distilled water), 1-fold metal mixture exposure group (1×MM, poisoning solution containing mercury chloride 0.15 mg/L, lead acetate trihydrate 25 mg/L, cadmium chloride 7.5 mg/L), 5-fold metal mixture exposure group (5×MM, poisoning solution containing mercury chloride 0.75 mg/L, lead acetate trihydrate 125.00 mg/L, cadmium chloride 37.50 mg/L), 10-fold metal mixture exposure group (10×MM, poisoning solution containing mercury chloride 1.50 mg/L, lead acetate trihydrate 250.00 mg/L, cadmium chloride 75.00 mg/L). Pregnant rats drank water until delivery. Twenty male pups were selected and exposed to these metals through breast milk until weaned. The heavy metals dose of poisoning water was adjusted, and then the weaned rats were exposed to heavy metals via drinking poisoning water until adulthood (postnatal day 83). The blood samples and brain hippocampus samples were collected to observe the ultrastructural changes of hippocampus, and to determine the levels of Hg, Pb and Cd in blood. In addition, apoptosis rate and fluorescence intensity of reactive oxygen species and intracellular free calcium concentration ([Ca²⁺]_i) in hippocampal neurons were measured. Results: Cellular factorial design analysis showed that Hg+Pb+Cd (at no observed adverse effect level, 1.0, 0.5 and 0.1 μmol/L, respectively)had a interaction on cell viability after 48 or 72 hours of combined exposure (P<0.05). The results of ultrastructure showed that mitochondria decreased, ridges and matrixes gradually dissolved in rat hippocampal neurons of 5×MM group; nuclear chromatin aggregated, more ridges and matrixes dissolved and the mitochondria also decreased in rat hippocampal neurons of 10×MM group. The concentration of Hg, Pb and Cd in the blood of 1×MM group, 5×MM group and 10×MM group were higher than those in the control group, and the differences were statistically significant (P<0.001). There was no significant difference in apoptosis rate between the 1×MM group and the control group. The apoptosis rate of 5×MM group and 10×MM group was higher than that in the control group, and the differences were statistically significant (P<0.001). There was no statistically significant difference in the fluorescence intensity of reactive oxygen species in hippocampal neurons of the 1×MM group and the control group. The fluorescence intensity of reactive oxygen species in the 5×MM group and the 10×MM group was higher than that in the control group, the difference was statistically significant (P<0.05). There was no significant difference in the fluorescence intensity of [Ca²⁺]_i between the 1×MM group and the control group. The fluorescence intensity values of [Ca²⁺]_i in the 5×MM group and the 10×MM group were higher than the control group, the differences were statistically significant (P<0.001). Conclusion Low-level combined exposure to Hg, Pb, and Cd caused synergistic neurotoxic damage, and the process may be related to the changes of neuronal apoptosis, reactive oxide species, and [Ca²⁺]_i levels.

Restricted cubic spline Cox proportional hazard regression model analysis is an important method of epidemiological multivariate survival analysis. By comparing the typical Cox regression model and the restricted cubic spline Cox regression model, this study expounds the limitations of the typical Cox regression model, and explains the basic principles and implementation process of the restricted cubic spline Cox proportional hazard regression model. When the follow-up data does not meet the application conditions of the typical Cox regression model, this method can be used to realize the correlation analysis between continuous exposure and outcomes.

Restricted cubic spline Cox proportional hazard regression model analysis is an important method of epidemiological multivariate survival analysis. By comparing the typical Cox regression model and the restricted cubic spline Cox regression model, this study expounds the limitations of the typical Cox regression model, and explains the basic principles and implementation process of the restricted cubic spline Cox proportional hazard regression model. When the follow-up data does not meet the application conditions of the typical Cox regression model, this method can be used to realize the correlation analysis between continuous exposure and outcomes.

Objective: To investigate the clinical effect of concentrated growth factor (CGF) applied in guided bone regeneration (GBR) for severe bone deficiency in the anterior maxilla. Methods : Forty patients with bone defects in the anterior maxilla were chosen to be treated with GBR, 20 patients were treated with CGF applied in GBR as the observation group, and the other 20 patients were treated only with GBR as the control group. The evaluation of wound healing was performed after the operation, and bone augmentation was evaluated half a year after the operation. Results: The first-stage healing rate of soft tissue wounds in the observation group was 100% and 75% in the control group, and the primary healing rate in the observation group was better than that in the control group (P=0.017). The changes in bone width of the observation group were （3.70 ± 0.28） mm, and those of the control group were （2.96 ± 0.16） mm. The bone augmentation in the observation group was higher than that in the control group (P=0.000). Conclusion CGF applied in GBR has a good effect on bone augmentation for severe bone deficiency in the anterior maxilla.

Objective: To study the segment of liver according to the large amount of three-dimensional(3D) reconstructive images of normal human livers and the vascular system, and to recognize the basic functional liver unit based on the anatomic features of the intrahepatic portal veins. Methods: The enhanced CT primitive DICOM files of 1 260 normal human livers from different age groups who treated from October 2013 to February 2017 provided by 16 hospitals were analyzed using the computer-aided surgery system.The 3D liver and liver vascular system were reconstructed, and the digital liver 3D model was established.The vascular morphology, anatomical features, and anatomical distributions of intrahepatic portal veins were statistically analyzed. Results: The digital liver model obtained from the 3D reconstruction of CAS displayed clear intrahepatic portal vein vessels of level four.Perform a digital liver segments study based on the analysis of level four vascular distribution areas.As the less anatomical variation of left hepatic portal vein, the liver was classified into four types of liver segmentation mainly based on right hepatic portal vein.Type A was similar to Couinaud or Cho′s segmentation, containing 8 segments(537 cases, 42.62%). Type B contained 9 segments as there are three ramifications of right-anterior portal vein(464 cases, 36.82%). The main difference for Type C was the variation of right-posterior portal vein which was sector shape(102 cases, 8.10%). Type D contained the cases with special portal vein variations, which needs three-dimensional simulation to design individualized liver resection plan(157 cases, 12.46%). These results showed that there was no significant difference in liver segmental typing between genders(χ²=2.179, P=0.536) and did not reveal any significant difference in liver segmental typing among the different age groups(χ²=0.357, P=0.949). Conclusions The 3D digital liver model can demonstrate the true 3D anatomical structures, and its spatial vascular variations.The observation of anatomic features, distribution areas of intrahepatic portal veins and individualized liver segmentation achieved via digital medical 3D visualization technology is of great value for understand the complexity of liver anatomy and to guide the precise hepatectomy.

Objective:To investigate the association of blood oxidative stress level with hypertriglyceridemia in the elderly aged 65 years and older in China.Methods:A total of 2 393 participants aged 65 years and older were recruited in 9 longevity areas from Heathy Aging and Biomarkers Cohort Study, during 2017 to 2018. Information on demographics characteristic, life style and health status were collected by questionnaire and physical examination, and venous blood was collected to detect the levels of blood oxidative stress and hypertriglyceridemia. The linear or non-linear association between oxidative stress and hypertriglyceridemia was described by restrictive cubic splines (RCS) fitting multiple linear regression model. The generalized linear mixed effect model was conducted to assess the association between oxidative stress and hypertriglyceridemia.Results:A total of 2 393 participants, mean age was 84.6 years, the youngest was 65 and the oldest was 112, the male was 47.9%(1 145/2 393), the triglyceride level was (1.4±0.8) mmol/L. The hypertriglyceridemia detection rate was 9.99%(239/2 393). The results of multiple linear regression model with restrictive cubic spline fitting showed that MDA level was linear association with triglyceride level; SOD level was nonlinear association with triglyceride level. MDA level had significantly association with hypertriglyceridemia, and the corresponding OR value was 1.063 (95% CI: 1.046,1.081) with 1 nmol/ml increment of blood MDA; SOD level had significantly association with hypertriglyceridemia, and the corresponding OR value was 0.986(95% CI: 0.983,0.989) with 1 U/ml increment of blood SOD. Conclusion:Among the elderly aged 65 and older in 9 longevity areas in China, MDA and SOD levels were associated with the risk of hypertriglyceridemia.

Objective:To investigate the association between blood lead concentrations and cognition impairment among Chinese older adults aged 65 or over.Method:Data was collected in 9 longevity areas from Heathy Aging and Biomarkers Cohort Study between 2017 and 2018. This study included 1 684 elderly aged 65 years and older. Information about demographic characteristics, socioeconomic factors, health status and cognitive function score of respondents were collected by questionnaire survey and physical examination. Venous blood of the subjects was collected to detect the blood lead concentration. Subjects were stratified into four groups ( Q 1- Q 4) by quartile of blood lead concentration. Multivariate logistic regression model was used to analyze the association between blood lead concentration and cognitive impairment. The linear or non-linear association between blood lead concentration and cognitive impairment were described by restrictive cubic splines (RCS). Results:Among the 1 684 respondents, 843 (50.1%) were female and 191 (11.3%) suffered from cognition impairment. After adjusting for confounding factors, the OR value and 95% CI of cognition impairment was 1.05 (1.01-1.10) for every 10 μg/L increase in blood lead concentration in elderly; Compared with the elderly in Q 1, the elderly with higher blood lead concentration had an increased risk of cognitive impairment. The OR value and 95% CIof Q2, Q3 and Q4 groups were 1.19 (0.69-2.05), 1.45 (0.84-2.51) and 1.92 (1.13-3.27), respectively. Conclusion:Higher blood lead concentration is associated with cognitive impairment among the elderly aged 65 years and older in 9 longevity areas in China.

Objective:To investigate the association of blood oxidative stress level with hypertriglyceridemia in the elderly aged 65 years and older in China.Methods:A total of 2 393 participants aged 65 years and older were recruited in 9 longevity areas from Heathy Aging and Biomarkers Cohort Study, during 2017 to 2018. Information on demographics characteristic, life style and health status were collected by questionnaire and physical examination, and venous blood was collected to detect the levels of blood oxidative stress and hypertriglyceridemia. The linear or non-linear association between oxidative stress and hypertriglyceridemia was described by restrictive cubic splines (RCS) fitting multiple linear regression model. The generalized linear mixed effect model was conducted to assess the association between oxidative stress and hypertriglyceridemia.Results:A total of 2 393 participants, mean age was 84.6 years, the youngest was 65 and the oldest was 112, the male was 47.9%(1 145/2 393), the triglyceride level was (1.4±0.8) mmol/L. The hypertriglyceridemia detection rate was 9.99%(239/2 393). The results of multiple linear regression model with restrictive cubic spline fitting showed that MDA level was linear association with triglyceride level; SOD level was nonlinear association with triglyceride level. MDA level had significantly association with hypertriglyceridemia, and the corresponding OR value was 1.063 (95% CI: 1.046,1.081) with 1 nmol/ml increment of blood MDA; SOD level had significantly association with hypertriglyceridemia, and the corresponding OR value was 0.986(95% CI: 0.983,0.989) with 1 U/ml increment of blood SOD. Conclusion:Among the elderly aged 65 and older in 9 longevity areas in China, MDA and SOD levels were associated with the risk of hypertriglyceridemia.

Atherosclerosis （AS） is a chronic inflammatory pathological process in which lipid and/or fibrous substances are deposited in the intima of arteries， and it is one of the pathological bases of many cardiovascular and cerebrovascular diseases. Endoplasmic reticulum stress （ERS） is a protective mechanism of cell adaptation. Moderate ERS can reduce abnormal protein aggregation and increase the degradation of misfolded proteins to repair and stabilize the internal environment， while excessive ERS can cause unfolded protein reaction， activate inflammation， oxidative stress， apoptosis， autophagy， and other downstream pathways， and lead to cell damage， or even apoptosis. A large number of studies have shown that ERS mediates a variety of pathological processes related to AS， affects endothelial cells， smooth muscle cells， macrophages， endothelial progenitor cells， and other cell components closely related to its occurrence and development， influences the progress of AS by regulating cell function， and promotes the formation of AS plaque， the transformation of stable plaque to unstable plaque， and the rupture of unstable plaque. Regulation of ERS may be a key target for the prevention and treatment of AS， and it is a research hotspot at present. Traditional Chinese medicine （TCM） believes that the origin of AS is the imbalance of Yin and Yang， the disharmony of Zangfu organs， and the abnormal operation of Qi， blood， and body fluid， which leads to the accumulation of phlegm， blood stasis， and other pathological products in the pulse channels， making the blood flow blocked or misfunction and causing the disease， which belongs to the syndrome of deficiency in origin and excess in superficiality. As the pathogenesis of AS is complex， and the symptoms are diverse， TCM has significant advantages in treating AS because of its multiple targets， multiple pathways， stable efficacy， strong individualization， and high safety. This paper systematically elaborated on the role of ERS in the occurrence and development of AS and summarized the mechanism research on the regulation and control of ERS by Chinese herbal monomer， Chinese herbal extract， Chinese herbal compound， and proprietary medicine， so as to provide a theoretical basis for clinical research and drug development in the prevention and treatment of AS.

Objective:To investigate the association between blood lead concentrations and cognition impairment among Chinese older adults aged 65 or over.Method:Data was collected in 9 longevity areas from Heathy Aging and Biomarkers Cohort Study between 2017 and 2018. This study included 1 684 elderly aged 65 years and older. Information about demographic characteristics, socioeconomic factors, health status and cognitive function score of respondents were collected by questionnaire survey and physical examination. Venous blood of the subjects was collected to detect the blood lead concentration. Subjects were stratified into four groups ( Q 1- Q 4) by quartile of blood lead concentration. Multivariate logistic regression model was used to analyze the association between blood lead concentration and cognitive impairment. The linear or non-linear association between blood lead concentration and cognitive impairment were described by restrictive cubic splines (RCS). Results:Among the 1 684 respondents, 843 (50.1%) were female and 191 (11.3%) suffered from cognition impairment. After adjusting for confounding factors, the OR value and 95% CI of cognition impairment was 1.05 (1.01-1.10) for every 10 μg/L increase in blood lead concentration in elderly; Compared with the elderly in Q 1, the elderly with higher blood lead concentration had an increased risk of cognitive impairment. The OR value and 95% CIof Q2, Q3 and Q4 groups were 1.19 (0.69-2.05), 1.45 (0.84-2.51) and 1.92 (1.13-3.27), respectively. Conclusion:Higher blood lead concentration is associated with cognitive impairment among the elderly aged 65 years and older in 9 longevity areas in China.