ObjectiveTo clarify whether epigallocatechin gallate （EGCG） is involved in the clearance of amyloid β-protein （Aβ） and autophagy induction by microglia， so as to explore the potential mechanisms of EGCG in the prevention and treatment of Alzheimer's disease （AD）. MethodsSix-month-old APP/PS1 mice were randomly divided into model and EGCG groups， with some additional wild type （WT） mice as the control group， each group consisting of 15 mice. The EGCG group received continuous gavage administration［5 mg/（kg·d）］ for 8 weeks， followed by the open field test and Y-maze to assess the learning and memory abilities of the mice. Thioflavin-S staining was used to evaluate the content and distribution of amyloid β-protein （Aβ）in the brain parenchyma of the mice， and immunofluorescence was employed to detect the expression levels of Aβ_1-42， glial fibrillary acidic protein （GFAP）， and ionized calcium-binding adapter molecule 1 （Iba1） in the hippocampal tissue of the mice. Additionally， N9 mouse microglial cells were induced with 20 µmol/L Aβ_1-42， and the cell viability was measured after treatment with different concentrations of EGCG （5 µmol/L， 10 µmol/L， 20 µmol/L）. Western blotting was used to detect the levels of Aβ_1-42， low density lipoprotein receptor-related protein 1（LRP1）， receptor for advanced glycation endproducts （RAGE）， amyloid precursor protein （APP）， insulin degrading enzyme （IDE）， neprilysin （NEP）， microtubule associated protein 1 hydrogen chain 3（LC3）-Ⅱ/LC3-Ⅰ， phosphatidylinositol 3-hydroxy kinase（PI3K）， p-PI3K， protein kinase B （AKT）， p-AKT， mammalian target of rapamycin （mTOR）， p-mTOR， and histone deacetylase 6（HDAC6）. Finally， through the co-culture of microglial cells and neuronal SH-SY5Y cells， cell viability and Caspase-3 levels were measured to verify the protective effect of EGCG-mediated Aβ clearance on neurons. ResultsEGCG increased the activity time and frequency of APP/PS1 mice in the central area of the open field （P<0.05）， and enhanced the percentage of alternation in the Y-maze test （P<0.01）； EGCG reduced Aβ deposition in the hippocampal tissue of APP/PS1 mice and increased the number of microglia； in vitro experiments showed that EGCG improved the survival rate of Aβ-induced N9 cells （P<0.01）， upregulated RAGE activity （P<0.05）， and promoted the internalization and phagocytosis of Aβ （P<0.01）. ECGC activated microglial autophagy by downregulating the level of HDAC6 （P<0.05）， inhibiting the phosphorylation of PI3K， AKT， mTOR （P<0.001）， and increasing the LC3-Ⅱ/LC3-I ratio （P<0.001）； EGCG improved the survival rate of SH-SY5Y cells （P<0.05） and reduced the activity of Caspase-3 （P<0.01） by clearing Aβ_1-42 through microglia， and had a protective effect on neurons. ConclusionEGCG activates microglial autophagy to clear Aβ by targeting and inhibiting the HDAC6-PI3K/AKT/mTOR axis.

Objective To study the application value of CAD/CAM technology in the teaching of inlay manufacturing.Methods A total of 60 undergraduates interned in the Department of Stomatology,Yan'an Hospital,Kunming Medical University were randomly divided into an experimental group(n=30)and a control group(n=30).We selected appropriate clinical cases for students to prepare for mandibular molar's proximal occlusal inlays.The instructor guided the results of the first preparation in different ways,and the students made the second modification and preparation,and the assessment team scored and evaluated the five aspects of the final preparation,the shape of the preparation,the shape of the occlusal surface,the dovetail retention,and the adjacent surface.Results The scores of all detection indexes in the experimental group were higher than those in the control group(P<0.05).Conclusion The application of CAD/CAM technology in inlay manufacturing teaching can effectively improve students'clinical hands-on ability and achieve better teaching effects than traditional teaching methods.

The purpose of this study was to investigate the damage mechanism of pathogenic E.coli on mouse brain microvascular endothelial cells(BMEC cells)and mouse alveolar macrophages(MH-S cells),as well as the lung and brain of healthy mice.In this study,BMEC cells and MH-S cells were infected with pathogenic E.coli strains,and cell morphological changes were observed.Plate counting method was used to detect the adhesion and invasion ability of the strains to cells and the number of bacteria in the lungs and brains of mice.RT-qPCR was used to detect the ex-pression of TNF-α,IL-1β and IL-6 genes in cells and mouse organs at different time periods.West-ern blot was used to detect the expression of p-NF-κB,p-JAK2 and p-STAT3 proteins related to inflammation in cells and mouse organs after infection.The results showed that the cell culture medium of the infection group was turbid,the cell vision became dark and blurred,some cells shrank and died,and more fragments were produced.The adhesion rate and invasion rate of BMEC cells at 3 h were significantly lower than those at 6 h(P＜0.050),and the adhesion rate and inva-sion rate of MH-S cells at 3 h were significantly higher than those at 6 h(P＜0.010).Infected mice had a large area of swelling and bleeding in the brain,and the lungs had different degrees of swell-ing and bleeding.The bacterial load in the brain and lung was the highest at 12 h.Compared with the control group,the mRNA expression levels of IL-1β,IL-6 and TNF-α in the infection group were significantly increased at 3 h and 6 h(P＜0.050),and the mRNA expression levels of inflam-matory factors in BMEC cells and MH-S cells were the highest at 6 and 3 h,respectively.The mR-NA expression of inflammatory factors in the brain and lung of infected mice showed a trend of in-creasing first and then decreasing with time,with the highest expression at 12 h after infection.The expression levels of p-NF-κB protein in BMEC cells,MH-S cells,lung and brain tissues of mice in the infection group were significantly higher than those in the control group(P＜0.001),and the expression levels of p-JAK2 protein and p-STAT3 protein were significantly lower than those in the control group(P＜0.050).The above results showed that pathogenic E.coli could adhere and invade BMEC cells and MH-S cells,colonize in lung and brain tissues of mice,promote the expres-sion of NF-κB protein in cells and tissues,inhibit the expression of JAK2 protein and STAT3 pro-tein,and then stimulate cells and tissues to produce inflammatory response.

Objective:To explore MRI T 2-mapping and blood oxygenation level dependent (BOLD) to evaluate the functional changes of paraspinal muscle in rats with discogenic low back pain (DLBP) after swimming. Methods:Totally 54 female 1-month-old SD rats were selected, which were divided into 3 groups by random number table method, sham operation (Sham) group, DLBP non-swimming group and DLBP swimming group, with 18 rats in each group. Under the guidance of X-ray fluoroscopy, the L4/5 and L5/6 intervertebral discs of the rats in the DLBP non-swimming group and DLBP swimming group were punctured by the posterior approach, and establishment of DLBP rat model by destroying nucleus pulposus, and only paraspinal muscles at the same level were punctured in the Sham group. After modeling, the DLBP swimming group received swimming exercise intervention for 5 consecutive days (30 min/d), while the DLBP non-swimming group and Sham group did not receive any rehabilitation exercise intervention. Each group was divided into 3 time point subgroups on average, the T 2-mapping and BOLD sequences were scanned at 30, 90 and 180 days after modeling to obtain the T 2 value, R 2* value of the paraspinal muscles, and the paraspinal muscles at the modeling level were taken for immunofluorescence staining, and the fluorescence intensity of myosin heavy chain (MYH)1 (type Ⅱ muscle fiber) and MYH7 (type I muscle fiber) was analyzed. One-way analysis of variance was used for comparison among the 3 groups, and the Bonferroni method was used for multiple comparisons, and Pearson correlation coefficient was used to evaluate the correlation between quantitative MRI parameters T 2 value, R 2* value and MYH1, MYH7 immunofluorescence intensity of rat paraspinal muscles at 180 days after modeling. Results:At 30 days after modeling, there was no significant difference in T 2 value and R 2* value among the 3 groups (all P>0.05). At 90 days after modeling, the T 2 value of the DLBP swimming group was higher than that of the DLBP non-swimming group, and the T 2 value of the DLBP non-swimming group was lower than that of the Sham group (all P<0.05), and there was no significant difference in the R 2* value among the 3 groups ( P>0.05). At 180 days after modeling, the T 2 value of the DLBP swimming group was higher than that of the DLBP non-swimming group, and the R 2* value was lower than that of the DLBP non-swimming group; the T 2 value of the DLBP non-swimming group was lower than that of the Sham group, and the R 2* value was higher than that of the Sham group (all P<0.05). At 30 and 90 days after modeling, there was no significant difference in the expressions of MYH1 and MYH7 among the 3 groups (all P>0.05). At 180 days after modeling, the expression of MYH1 decreased and the expression of MYH7 increased in the DLBP swimming group compared with the DLBP non-swimming group; the expression of MYH1 increased and the expression of MYH7 decreased in the DLBP non-swimming group compared with the Sham group (all P<0.05). At 180 days after modeling, the T 2 value had a moderate negative correlation with the fluorescence intensity of MYH1 ( r=-0.511, P=0.043), and a moderate positive correlation with the fluorescence intensity of MYH7 ( r=0.564, P=0.023); R 2* value was moderate positive correlated with the fluorescence intensity of MYH1 ( r=0.625, P=0.010), and moderate negative correlated with the fluorescence intensity of MYH7 ( r=-0.653, P=0.006). Conclusions:Swimming exercise can improve the reduction of water content and perfusion in the paraspinal muscles of DLBP rats, and reduce the transformation of muscle fibers from type Ⅰ to type Ⅱ, the changes of T 2 and R 2* value can reflect the transformation of paraspinal muscle fiber types to a certain extent.

Objective:To explore the key genes related to the development, progression and prognosis of acute myeloid leukemia (AML) based on bioinformatics, and to analyze their functions.Methods:The chip expression profile GSE84881 data set of AML patients including 19 AML samples and 4 normal tissue samples was downloaded from the gene expression omnibus (GEO) database. GEO online tool GEO2R was used to screen the differentially expressed genes (DEG). The DAVID online database was used to make gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis of DEG. The STRING online database was used to analyze the protein interaction (PPI) network of DEG, and the key genes were screened by using the Cytoscape software. The weighted gene co-expression network analysis (WGCNA) was used to build co-expressed network and obtain the central genes.LC-Bio online platform was used to construct Venn diagram and the key genes and central genes in PPI were crossed to finally obtain the true key genes. RNA-seq datasets GSE2191 and GSE90062 of human tissues were downloaded from GEO database to verify the screened key genes. Kaplan-Meier method was used to analyze the effects of key genes on the overall survival (OS) of AML based on the data of GEPIA database.Results:A total of 247 DEG were identified in GSE84881 data set, including 112 up-regulated genes and 135 down-regulated genes. According to the results of GO enrichment analysis, 247 DEG were mainly enriched in the regulation of signal transduction and cell proliferation in the biological process (BP); the cell composition (CC) revealed that these genes were mainly involved in the cytoplasm and exosomes; the molecular function (MF) analysis showed that these genes were mainly enriched in protein binding and calcium binding. Further KEGG pathway enrichment analysis showed that these 247 DEG were mainly involved in NOD-like receptor signal pathway and interleukin 17 (IL-17) signal pathway. And then the 12 key genes were obtained from PPI. WGCNA software was used to screen 13 central genes from GSE84881 dataset and finally 1 real key gene EGF was obtained after taking intersection. Kaplan-Meier method showed that OS time of AML patients in EGF high expression group was decreased than that in EGF low expression group, and the difference was statistically significant( P = 0.044). Conclusions:EGF may be an important diagnosis and treatment target of AML and may become a potential biomarker for clinical treatment and prognosis prediction of AML.

In Vivo Dosimetry ; Radiotherapy Dosage ; Radiometry/methods* ; Electronics ; Radiotherapy, Intensity-Modulated/methods* ; Phantoms, Imaging ; Algorithms

Inflammatory myofibroblastic tumor (IMT)is a potentially or low-grade malignant mesenchymal neoplasm, which is rare in clinic. Renomedullary interstitial cell tumor(RICT) is a clinically rare benign renal tumor. The combination of these two diseases in one patient has not been reported. A 25-year-old female patient was admitted to the hospital due to left back pain for 12 days and hematuria for 1 week. MRI of kidneys showed a mass in the left renal pelvis, which was considered as renal pelvic carcinoma. Urine cytopathological examination was negative. Robot-assisted laparoscopic radical left nephroureterectomy was performed. There was no tumor recurrence or metastasis during the follow-up for more than 6 months after operation.

Epigenetic modification includes DNA methylation, histone modification, non-coding RNA, etc., and is crucial in determining gene expression. A growing number of recent studies have shown that epigenetic regulation may play a central role in the pathogenesis of sepsis. Due to its explicit mechanism and relatively mature technic, DNA methylation has received extensive attention in sepsis-related researches. By examining recent studies on septic DNA methylation mechanism, this review elucidates the key role in sepsis occurrence and progression that DNA methylation plays from etiology, immunology and other aspects, as well as its application potential in the diagnosis, prognosis and treatment of sepsis before pointing out the direction for further research.

Objective:To observe the effects of static 70° head-up tilted standing and of repeated body repositioning on hemodynamics in healthy young and middle-aged persons.Methods:The hemodynamics of 24 middle-aged and 23 younger persons were studied. Both groups were requested to perform static 70° head-up tilted standing and to repeatedly change their body position from 0° to 70° of tilt at a velocity of 1°/second for ten minutes in a random order. Before, between and after each test the subjects rested supine for ten minutes. Hemodynamic variables and blood pressure were recorded non-invasively.Results:The average heart rate (HR) increased significantly in both groups when rising from supine to the testing positions. In 70° tilted standing the average HR of the youth group, 84.0±9.5bpm, was significantly higher than that in the other position and that of the middle-aged group in the same position. The average HR of the middle-aged group in 70° tilted standing was also significantly higher than in the other position. Among the middle-aged group, the average stroke volume (SV) in the testing positions was significantly lower than when resting. Significant differences were observed in the average diastolic blood pressure (DBP) between the testing and rest positions for both groups, with the average DBP of the middle-aged group significantly higher than that of the youth group in all three positions. Among the youth group, the average SV, CO and systolic blood pressure (SBP) of the males were significantly higher than among the females in all of the different body positions.Conclusions:Young persons mainly rely on an increased heart rate to maintain cardiac output while middle-aged participants appear to achieve this through increased peripheral resistance. Repeated position changes have less impact on hemodynamics than 70° inclined standing, making it a safer and more stable training method. However, the long-term effects of such intervention need to be confirmed in further studies.

Objective:To compare the pathological results and complications of limited and extended pelvic lymph node dissection among high-risk prostate cancer patients, and to explore the risk factors that affect the rate of lymph node metastasis in high-risk prostate cancer patients.Methods:The data of 800 high-risk prostate cancer patients who underwent radical prostatectomy and pelvic lymph node dissection from January 2016 to December 2020 in three affiliated hospital of Sun Yat-sen University were analyzed retrospectively. According to the scope of pelvic lymph node dissection, they were divided into limited pelvic lymph node dissection (LPLND) group and extended pelvic lymph node dissection (EPLND) group. There were 172 patients underwent LPLND, and 628 patients underwent EPLND.The age of the patients in the LPLND group was 67 (62, 72) years old, diagnosed PSA 20.7 (10.9, 54.8) ng/ml. The biopsy Gleason score 6 in 22 cases, 7 in 59 cases, 8 in 56 cases and 9-10 in 35 cases.The clinical T stage: T 1 in 29 cases, T 2 in 102 cases, T 3 in 37 cases, T 4 in 4 cases; N 0 in 160 cases and N 1 in 12 cases. 50 patients received neoadjuvant hormonal therapy. The age of patients in the EPLND group was 67 (63, 72) years old, diagnosed PSA was 23.9 (14.0, 46.8) ng/ml. Biopsy Gleason Score 6 in 51 cases, 7 in 194 cases, 8 in 218 cases and 9-10 in 165 cases. Clinical T stage: T 1 in 114 cases, T 2 in 341 cases, T 3 in 144 cases, T 4 in 29 cases; N 0 in 526 cases and N 1 in 102 cases.158 patients received neoadjuvant hormonal therapy. There were no significant differences in the age, PSA, puncture Gleason score, clinical T stage, and whether or not to receive neoadjuvant hormonal therapy between the two groups of patients ( P>0.05). The difference in clinical N staging was statistically significant ( P=0.002). The number of postoperative lymph nodes, positive pelvic lymph nodes and postoperative complications and other related clinical and pathological data of the two groups were analyzed. Multivariate logistic regression was used to analyze the risk factors of patients with positive lymph nodes. Results:The median number of lymph nodes harvested [13(8, 19)vs. 6(4, 13), P<0.001] and the rate of positive lymph node cases[31.2%(196/628) vs. 10.5%(18/172), P<0.001] in the EPLND group was significantly higher than those in the LPLND group. Preoperative PSA, clinical N staging, Gleason score, and way of lymph node dissection were independent risk factors for postoperative positive pelvic lymph node in high-risk prostate cancer patients. Compared with the LPLND group, the ELPND group had a higher postoperative complication rate [19.9%(125/628) vs. 11.0%(11/172), P=0.007]. Conclusions:Compared with the LPLND, EPLND in high-risk prostate cancer patients can harvest more lymph nodes and increase the detection rate of positive lymph nodes. The complications of EPLND were higher than those of LPLND. Preoperative PSA, clinical N stage, Gleason score, and the way of lymph node dissection are independent risk factors for positive pelvic lymph node dissection.