Objective: To estalish a rat model system in which periapical lesions were induced by pulp exposure and infection from the oral environment. Methods: The pulps of mandibular molar of 16 SD rats were surgically exposed and kept open to be induced for infection from the oral environment. The rats were killed 1, 2, 3, 4 weeks after operation respectively. Radiographic image analysis was performed by means of computer linked to a video image digital analysis system. In addition, specimens were decalicified, sectioned, HE stained and examined under microscope. Results: Periapical lesions were readily detectable as early as 1 week after pulp exposure. A significant increase in lesion area was detected from 1 to 3 weeks in a time-dependent manner, the lesion declined a little bit in 4 weeks. Slight inflammatory cell infiltration and alveolar bone resorption were observed in the periapical tissue in the 1-week-samples, total pulp necrosis in the 2-week-samples, apical abscess and bone destruction in the 3-week-samples. Decreased infiltration and the matured osteoblasts were found on the surface of the bone in the 4-week-samples. Conclusion: Pulp exposure can induce periapical lesion in rat. A period of rapid lesion development occurs between day 7 and day 21 after pulp exposure (active phase), and a period of slower development follows thereafter (chronic phase).

Objective To collect information of patient doses of interventional radiology in Beijing Xuanwu Hospital,and investigate correlation between the peak skin dose(PSD) and dose-area product(DAP).Methods Radiation doses from 135 patients have been studied including 84 coronary angiographies(CAG) and 51 percutaneous transluminal coronary angioplasties(PCI).Dose-area product(DAP) values,cumulative dose(CD) at interventional reference points,fluoroscopy times,total number of cine frames were collected for each patient.Skin dose measurements were made with thermoluminescent dosimeters(TLD) placed as a 10 ? 9 arrays of TLDs on the body.The grid of TLDs arrays was 5 ? 4 cm.Results Mean values for dose-area product were 2690.84 ?Gym2 for CAG and 7946.91 ?Gym2 for PCI.Mean values for CD were 431.6 mGy cm2 for CAG and 1395.3 mGy for PCI.Mean fluoroscopy times were 2.9 min for CAG and 10.9 min for PCI and mean number of frames were 544 and 945 for CAG and PCI,respectively.PSD values ranged from 26.18 to 120.37 mGy for CAG and 38.91 to 184.79 mGy for PCI.The relationship between DAP and PSD was r = 0.52 for CAG and r = 0.54 for PCI.The correlation of PSD with CD was r = 0.45 for CAG and r = 0.53 for PCI.Conclusion Comparison shows that patients DAP,CD and fluoroscopy time values were comparable with other publications.Skin dose values of investigated patients are below the threshold dose for radiation skin injury(2 Gy).There is no good relationship between DAP and PSD.So calculation of individual maximum skin dose based on DAP data is not reliable and needs to find a new reference value for skin dose.(J Intervent Radiol,2007,16:222-225)

0 55). The Vmax and Vmin of the patients were singnificantly higher than those of healthy people. The RI of healthy subjects was higher than that of the patients. The Vmax and Vmin of the kidney with tumor was singnificantly higher than that of the other normal kidney side. Conclusion The hemodynamic features of the kidney tumors and kidney artery were valuable to the differential diagnosis of the malignant and benign kidney tumors.

Objective To verify the analytical performance of the Roche cobas 8000 automatic biochemical analyzer.Methods The intra-batch and inter-batch precisions,accuracy,linearity and reference interval were validated according to the Clinical and La-boratory Standards Institute (CLSI)documents (EP5-A2,EP15-A2,EP6-A;C28-A2 ).Results The intra-batch precision was 0.5%-2.3% and the inter-batch precision was 0.8%-3.11%,which were all less than 1/4 Tea(CLIA'88).The detection results of various items had better correlation with the target values(r2 >0.99);the linear range of various detected items were in line with the linear range provided by the specification;the quotative biological reference range conformed to the group of this laboratory services.Conclusion The various performance indexes of the Roche cobas 8000 automatic biochemical analyzer conform to the qual-ity requirements and this analyzer can be used in clinical biochemical detection work..

AIM The purpose of this study was to investigate the effect of immunosuppression on the periapical inflammation by estimating the expression of the cytokine IL-1? and TNF-? in periapical lesion of rat. METHODS Sixteen SD rats received cycolophosphamide injection weekly before pulp exposure for three weeks, another 16 animals received no medication as control group. The expressions of IL-1? and TNF-? mRNA in periapical lesion were detected by methods of in situ hybridization,and semi-quantified analyzed compared with control group. RESULTS IL-1? and TNF-? mRNA expressions in treated group increased progressively from 1 to 3 week, and declined somewhat at 4 week. There was a statistically significant positive correlation between the area of the periapical lesion and the number of positive stained cell for IL-1? and TNF-?(IL-1?:r=0 881,P

0.05).The frequency of VV genotype of Mn-SOD in the DR(+) group was significantly higher than that in the DR(-) group(92.0% vs 77.1%,P

Bicuspid ; Dental Pulp Cavity ; pathology ; Humans ; Mandible ; Root Canal Therapy

Objective:To investigate the prognostic factors and pathological characteristics of mixed subtype thyroid cancer (MSTC) .Methods:Data of 41 cases of MSTC, which were confirmed by postoperative pathology, among from 24, 912 cases of thyroid cancer admitted in Mar. 2005 to Aug. 2020 in the First Medical Center of Chinese People’s Liberation Army General Hospital, were retrospectively analyzed. 37 cases underwent surgical treatment, while 4 cases only underwent puncture to confirm the pathology due to physical conditions, and no surgical treatment was performed. The tumor size, number of lesions, capsule invasion, AJCC 8th TNM staging, surgical methods, radiotherapy and chemotherapy were collected. The MSTC patients in the group were followed up to obtain the postoperative situation. SPSS 25.0 and R studio statistical software was used for data processing, and Cox single factor and multivariate regression were used to analyze independent risk factors.Results:In the 41 cases, there were 9 cases of papillary carcinoma (PTC) mixed with follicular carcinoma (FTC) , and 8 cases of mixed medullary and follicular carcinoma (MMFTC) . There were 15 cases of poorly differentiated thyroid cancer (PDTC) , 4 cases of squamous cell carcinoma of thyroid (SCCT) , and 5 cases of undifferentiated thyroid carcinoma (ATC) . The median follow-up time was 18 months, and 11 patients died during the follow-up, with a mortality rate of 26.8%. Average onset age was (51.41+15.69) years. 4 cases had postoperative recurrence during the follow-up, including 2 cases of local recurrence, and 2 cases of distant metastasis. Single factor results showed that age, degree of tumor differentiation, surgical method, radiotherapy and chemotherapy were the risk factors affecting the prognosis of patients with MSTC ( P<0.05) . Multivariate analysis showed that age at diagnosis ( P=0.007) and surgical procedure ( P=0.017) were independent risk factors for prognosis in patients with MSTC. Conclusion:Middle-aged and elderly women are at high risk for MSTC, and the degree of tumor differentiation is proportional to survival. Due to the multi-type and pleomorphic pathological findings, a reasonable treatment plan has good effects on prognosis of MSTC.

Objective To explore the effect of sodium arsenite (iAs3+) and sodium hydrogen arseuate (iAs5+) exposure on rat multidrug resistance protein 2 (MRP2) expression,and the correlation of liver arsenic and its methylation products,and to provide a basis for further elucidating the mechanism of arsenic toxicity.Methods Seventy wistar rats were randomly divided into seven groups,10 rats in each group.Control group was administrated with deionized water.Sodiun arsenite high-dose group,middle-dose group,low-dose group were administrated with different concentrations of sodium arsenite:20.0,6.7 and 2.2 mg/kg BW every day,respectively.Animals were sacrificed 90 days later by cervical dislocation to collect liver,the expression of MRP2 in the membrane of hepatocyte was determined by Western blotting.HPLC-HGAFS was employed to determine the content or level of arsenic and its methylation products.Correlation between expression of MRP2 and arsenic methylation products was analyzed using Pearson's linear correlation method.Results The MRP2 protein levels of control group,iAs3+ and iAs5+ high-,middle-,low-dose groups were 1.21 ± 0.13,1.85 + 0.09,1.65 + 0.19,1.61 + 0.18,1.69 + 0.04,1.42 + 0.19,1.27 ± 0.10.Compared to control group,MRP2 protein levels of iAs3+ high-,middle-,low-dose group and iAs5+ high-dose group were increased (P ＜ 0.05); Compared with the low-dose group,MRP2 protein levels of iAs3+ and iAs5+ high dose groups were increased(P ＜ 0.05); Comparing the matched doses group of iAs5+ and iAs3+,MRP2 protein levels of iAs3+ high-,middle-,low-dose group were higher than iAs5+(P ＜ 0.05).Meanwhile,there was a significant positive relationship between the expression of MRP2 and the content of iAs3+,MMA and DMA in iAs3+ exposed group(r =0.575,0.678,0.395,all P ＜ 0.05).There was also a significant correlation between the expression of MRP2 and MMA and IMA in iAs5+ exposed group(r =0.593,0.643,all P ＜ 0.05).There was no significant relationship between the expression of MRP2 and the content of iAs5+in iAs5+ exposed group.Conclusions The expression of MRP2 is increased with increasing dose of arsenic exposure,thus resulting in compensatory changes on MRP2 expression in the liver cell membrane.MRP2 efflux may play an important role in the metabolic pathways of iAs3+.The level or load of arsenic methylation in liver is closely related with MRP2 expression.

OBJECTIVE:To prepare Xuangui zhitong dispersible tablets and optimize its formulation technology. METHODS:Using disintegration time as index,single factor test was conducted for filler,disintegrating agent,the types and amount of adhe-sives and compression pressure. The amount of mixed disintegrating agent,avicel and gum arabic were optimized by orthogonal test. The tablet quality by optimized formulation was detected,and disintegration time,the content and dissolution rate of tetrahy-dropalmatine were determined;the similarity of in vitro dissolution rate of dispersible tablets and dropping pills were evaluated by similarity factor test. RESULTS:The optimized formulation was composed of 25% MCC as fillers,9% PVPP and 9% L-HPC as mixed disintegrants,85% ethanol solution as adhesives,micro-silica gel 2%,compression pressure of 3.0 kg/cm2. The average dis-integration time was 1.22 min,and the content of tetrahydropalmatine was 1.097 mg/g. The accumulative dissolution rate was more than 80% at 10 min and more than 90% at 15 min. The similarity factor f2 of dissolution curve was 62,using dropping pills as ref-erence preparation. CONCLUSIONS:Xuangui zhitong dispersible tablet had a rapid disintegration and the behavior of dissolution is similar to Xuangui zhitong dropping pills.