Objective:To establish a rapid and precise dose measurement method with EBT4 film and ensure its measurement accuracy to be within the required range through strict operational procedures for the purpose of addressing the two essential issues of poor measurement accuracy and timeliness of EBT film under FLASH conditions.Methods:After storing under different humidity conditions for a certain period of time, the film was exposed to radiation for analyzing the influence of air humidity on the intrinsic performance of EBT film. By means of repeated scanning operations and the film angle rotation, the influences of repeated scanning and film placement angle were analuzed. Parabolic correction method was used to reduce the spatial position influence during the scanning process. By analying the relationship between net optical density (netOD) and absorbed dose through the comparison of three fitting method, the optimal fitting curve was selected. After irradiation of the same batch of films for 5 min and 24 h, the film doses were calibrated and then compared with ionization chamber-measured result. The rapid and precise film dosimetry method was used to measure both the percentage depth dose from X-rays at ultra-high dose rate and the dose distribution at a depth of 2 cm in water.Results:Air humidity had the greatest influence on the intrinsic performance of EBT film (approximately 20%). The average deviation of repeated scans is within 0.5%. The angle at which the film is placed significantly affected the readouts of the film with the maximum influence approximately 70%. The net optical density combined with polynomial fitting can control the fitting residuals of 1-16 Gy within 3%. The change rate of light channels at 5 min already mostly met the requirements of the rapid mode (< 0.5%). Compared with the measurement result obtained using the reference ionization chamber, the deviations of the 5 min or 24 h dose calibration curves were all within 2%.Conclusions:The EBT4 film can be employed as a precise dosimeter to quickly measure the FLASH radiation dose. Rapid and precise FLASH dose measurements can meet the stringent requirements of both preclinical and clinical FLASH research.

Objective:To establish a rapid and precise dose measurement method with EBT4 film and ensure its measurement accuracy to be within the required range through strict operational procedures for the purpose of addressing the two essential issues of poor measurement accuracy and timeliness of EBT film under FLASH conditions.Methods:After storing under different humidity conditions for a certain period of time, the film was exposed to radiation for analyzing the influence of air humidity on the intrinsic performance of EBT film. By means of repeated scanning operations and the film angle rotation, the influences of repeated scanning and film placement angle were analuzed. Parabolic correction method was used to reduce the spatial position influence during the scanning process. By analying the relationship between net optical density (netOD) and absorbed dose through the comparison of three fitting method, the optimal fitting curve was selected. After irradiation of the same batch of films for 5 min and 24 h, the film doses were calibrated and then compared with ionization chamber-measured result. The rapid and precise film dosimetry method was used to measure both the percentage depth dose from X-rays at ultra-high dose rate and the dose distribution at a depth of 2 cm in water.Results:Air humidity had the greatest influence on the intrinsic performance of EBT film (approximately 20%). The average deviation of repeated scans is within 0.5%. The angle at which the film is placed significantly affected the readouts of the film with the maximum influence approximately 70%. The net optical density combined with polynomial fitting can control the fitting residuals of 1-16 Gy within 3%. The change rate of light channels at 5 min already mostly met the requirements of the rapid mode (< 0.5%). Compared with the measurement result obtained using the reference ionization chamber, the deviations of the 5 min or 24 h dose calibration curves were all within 2%.Conclusions:The EBT4 film can be employed as a precise dosimeter to quickly measure the FLASH radiation dose. Rapid and precise FLASH dose measurements can meet the stringent requirements of both preclinical and clinical FLASH research.

Objective : To compare the osteogenic differentiation ability of human apical papilla stem cells (SCAPs) , dental pulp mesenchymal stem cells (DPSCs) and alveolar bone mesenchymal stem cells (ABMMSCs) in vitro. Methods : The apical papilla stem cells , dental pulp mesenchymal stem cells and alveolar bone mesenchy⁃ mal stem cells isolated from the third molars and alveolar bone tissues were cultured and passaged. The morphology of primary and P3 generation cells was observed under a microscope. Flow cytometry was used to detect cell immunophenotype. Real⁃time fluorescent quantitative PCR (qRT⁃PCR) and cell counting kit⁃8 were used to analyze cell senescence and proliferation ability. After osteogenic induction , alkaline phosphatase (ALP) and alizarin red staining and qRT⁃PCR were used to detect osteogenic related genes to compare osteogenic ability. Results: There was no significant difference in the morphology of the three cells , which showed the morphology of fibroblasts , long spindle⁃shaped , smooth and uniform after passage. There were no senescence differences among the 3 types of cells , all of which maintained stable proliferative capacity ; the proliferation capacity of SCAPs was significantly higher than that of the other 2 types of cells , and the proliferation capacity of ABMMSCs was weaker; ALP staining and alizarin red staining after 7 and 14 d osteogenesis induction showed that the osteogenic ability of ABMMSCs was significantly stronger than that of SCAPs and DPSCs ; qRT⁃PCR showed that ABMMSCs had the most significant inrease in osteogenesis⁃related genes. Conclusion SCAPs , DPSCs and ABMMSCs have stable biological properti and can undergo osteogenic differentiation , and ABMMSCs have stronger osteogenic ability than DPSCs and SCAPs in vitro.

OBJECTIVE: To investigate the persistent damage of learning and memory ability after the cessation of sub-chronic manganese(Mn)-exposure in rats. METHODS: Specific pathogen free weaning male SD rats were randomly divided into control group and low-, medium-and high-dose groups based on body weight, with 6 rats in each group. Rats were intraperitoneally injected with Mn chloride(MnCl_2·4 H_2O) at the concentrations of 0, 5, 10, or 20 mg/kg body weight, 5 days per week for 6 weeks and continued to be observed for 12 weeks after the cessation of Mn-exposure. During the experiment, the body mass of the rats was weighed. Learning and memory ability was evaluated by a Morris water-maze task at the 6 th weeks of Mn-exposure(cessation of Mn-exposure of week 0), the 6 th and 12 th week of the cessation of Mn-exposure. The organ coefficients of heart, liver, spleen, kidney and testicles were evaluated after the cessation of Mn-exposure on week 12. RESULTS: The body mass of the high-dose group was lower than that of the other 3 groups(P<0.05) at the 4 th and 6 th week of Mn-exposure and the 2 nd week of the cessation of Mn-exposure. There was no significant difference in body mass between the groups(P>0.05) on the 12 th week of the cessation of Mn-exposure. The escape latency of high-dose group was higher than that of the control group(P<0.05), and the number of platform crossings in the low-, medium-and high-dose groups were fewer than that in the control group(P<0.05) after the cessation of Mn-exposure. The escape latency was shorter and the numbers of platform crossings were higher on the 6 th and 12 th week of the cessation of Mn-exposure(P<0.05) when compared with that of the 6 th week of Mn-exposure rats. There was no statistical significance in the organ coefficients of heart, liver, spleen, kidney and testicles among the 4 groups at the 12 th week of the cessation of Mn-exposure in rats(P>0.05).CONCLUSION: Sub-chronic Mn exposure can impair learning and memory ability of rats, and the damage persists after the cessation of Mn-exposure.

Objective: To explore the improvement rate of liver fibrosis in patients with chronic hepatitis B virus infection who received entecavir alone or in combination with anluohuaxianwan for 78 weeks. Methods: Patients with chronic HBV infection were randomly treated with entecavir alone or in combination with anluohuaxian for 78 weeks. Ishak fibrosis score was used for blind interpretation of liver biopsy specimens. The improvement in liver fibrosis condition before and after the treatment was compared. Student's t test and non-parametric test (Mann-Whitney U-Test and Kruskal-Wallis test) were used to analyze the measurement data. The categorical variables were analyzed by Chi-square test method and Spearman’s rank correlation coefficient was used to test bivariate associations. Results: Liver fibrosis improvement rate after 78 weeks of treatment was 36.53% (80/219) and the progression rate was 23.29% (51/219). The improvement of liver fibrosis was associated to the degree of baseline fibrosis and treatment methods (P < 0.05). The improvement rate of hepatic fibrosis in patients treated with anluohuaxianwan combined with entecavir at baseline F < 3 (54.74%, 52/95) was significantly higher than that in patients treated only with entecavir (33.33%, 16/48), P = 0.016 and the progression rate of hepatic fibrosis (13.68%, 13/95) was lower than that in patients treated alone (18.75%, 9/48), P = 0.466. In patients with baseline F < 3, the proportion of patients with improved and stable liver fibrosis in the combined treatment group (68.1%, 32/47) was higher than that in the treatment group alone (51.7%, 15/29). Conclusion Combined anluohuaxianwan and entecavir treatment can significantly improve the improvement rate of liver fibrosis in patients with chronic hepatitis B virus infection. Furthermore, it has the tendency to improve the stability rate and reduce the rate of progression of liver fibrosis.

BACKGROUND:Human umbilical cord mesenchymal stem cels (hUC-MSCs) can obviously relieve liver cirrhosis, and thereby repair liver injury. However, the molecular mechanism of hUC-MSCs therapy for liver cirrhosis is limited at present, and especialy the non-coding RNA regulation of hepatic gene changes has not been detailed. OBJECTIVE:To investigate the changes of microRNA after hUC-MSCs therapy in rats with liver cirrhosis. METHODS:Liver cirrhosis models were established in rats using carbon tetrachloride subcutaneous injection plus oral administration of alcohol. At 8 weeks after modeling, hUC-MSCs were injectedvia the tail vein once a week for 4 consecutive weeks. At 1 week after the last injection, rat liver tissues were colected for paraffin embedding. Liver RNA was extracted for gene chip analysis. Blood samples were colected and analyzed using an automatic biochemical analyzer to detect the changes of liver function. RESULTS AND CONCLUSION:Alanine aminotransferase, aspartate aminotransferase and gamma-glutamyl transpeptidase were improved significantly after hUC-MSCs therapy. Fat lesions and necrosis of hepatocytes were significantly reduced. MicroRNA expression microarray hybridization analysis and PCR results showed that rno-miR-369-5p, rno-miR-3584-5p and rno-miR-153* were down-regulated during modeling and increased after hUC-MSCs therapy. And rno-miR-93, rno-miR-199a-3p, rno-miR-195, rno-let-7a and rno-miR-19a were firstly up-regulated in the process of modeling and then down-regulated obviously after hUC-MSCs therapy. These results suggest that hUC-MSCs may reverse liver cirrhosis and liver cel damage through up-regulation of rno-miR-369-5p, rno-miR-3584-5p and rno-miR-153*, and down-regulation of rno-miR-93, rno-miR-199a-3p, rno-miR-195, rno-let-7a and rno-miR-19a.

OBJECTIVETo investigate the relationship between the expression of hepatitis B virus (HBV) core antigen and viral replication and liver tissue inflammation damage in chronic hepatitis B (CHB) patients, and to analyze the relationship of core antigen expression differences with clinical and pathological features in e antigen-negative and e antigen-positive CHB patients.

METHODSSixty-three treatment-naive patients diagnosed with CHB who underwent liver biopsy were included in this retrospective analysis. Liver pathology was assessed, and the karyotype, pulp type, and pulp karyotype were determined. Core and e antigen expression was quantitatively determined by automated immunoassay. Blood samples were used to determine the amount of peripheral lymphocytes or monocytes and HBV DNA load. Results The median titer of HBV DNA was significantly higher in the CHB patients with e antigen positivity (n = 48) than those with e antigen negativity (n = 15) (5.4 * 106 copies/ml vs. 5.4 * 104 copies/ml, P = 0.003). The core antigen positive expression rate was significantly higher in the e antigen-positive CHB patients than in the e antigen-negative CHB patients (80.33% vs. 53.33%, P = 0.042). For the e antigen-positive CHB patients, the HBV DNA titer in karyotype core antigen cases was higher than that in the pulp karyotype mixed-type cases (P = 0.008) and in the negative cases (P = 0.013); in addition, the karyotype patients showed higher titer than the plasma patients (P = 0.019). Also for the e antigen-positive CHB patients, the HBV DNA titer was positively correlated with the rank level of pulp karyotype in core antigen expression (r = 0.589, P = 0.003) but negatively correlated with lobular inflammation, interface inflammation, and fibrosis level (r = -0.552, P = 0.000; r = -0.381, P = 0.008; r = -0.555, P = 0.000); in addition, the level of peripheral blood lymphocytes was negatively correlated with lobular inflammation and fibrosis level (r = -0.361, P = 0.012; r = -0.356, P = 0.013). For the e antigen-negative CHB patients, the level of peripheral blood lymphocytes was negatively correlated with lobular inflammation and interface inflammation (r = -0.702, P = 0.004; r = -0.578, P = 0.024), while the level of peripheral blood mononuclear cells was negatively correlated with lobular inflammation, interface inflammation, and fibrosis level (r = -0.682, P = 0.005; r = -0.620, P = 0.014; r = -0.527, P = 0.044); in addition, age positively correlated with interface inflammation (r = 0.690, P = 0.004).

CONCLUSIONThe pulp karyotype mixed-type of core antigen expression may reflect the level of HBV replication. Negative expression of core antigen may be associated with variation in pre-C or C zone. The monocyte-macrophage system may be involved in the pathogenesis of e antigen-negative CHB, while the mechanism of immune escape may play an important role in increasing HBV DNA titer in an e-antigen-negative CHB condition.

Adult ; Aged ; DNA, Viral ; blood ; Female ; Hepatitis B Core Antigens ; blood ; Hepatitis B virus ; physiology ; Hepatitis B, Chronic ; blood ; pathology ; virology ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Viral Load ; Virus Replication ; Young Adult