OBJECTIVEThis study aims to identify the crack tip stress intensity factor of the propagation process, crack propagation path, and the changes in the shape of the crack tip by the finite element method.

METHODSThe finite element model of dentino-enamel junction was established with ANSYS software, and the length of the initial crack in the single edge was set to 0.1 mm. The lower end of the sample was fixed. The tensile load of 1 MPa with frequency of 5 Hz was applied to the upper end. The stress intensity factor, deflection angle, and changes in the shape of the crack tip in the crack propagation were calculated by ANSYS.

RESULTSThe stress intensity factor suddenly and continuously decreased in dentino-enamel junction as the crack extended. A large skewed angle appeared, and the stress on crack tip was reduced.

CONCLUSIONThe dentino-enamel junction on human teeth may resist crack propagation through stress reduction.

Objective To explore the differential diagnostic significance of clone analysis for multicentric occurrence (MO) and intrahepatic metastasis (IM) in hepatocellular carcinomas (HCCs).Methods Loss of heterozygosity (LOH) and microsatellite instability (MSI) were analyzed by microsatellite polymorphism test and the integration sites of HBV were assessed by Southern blot in each nodule of the HCCs. The clonalities were then compared between each nodule of the same patient and the diagnosis of MO or IM was concluded. Finally, the results based on clonality analysis were compared with those according to clinicopathological and imaging data. Results According to the results of LOH and MSI in 79 nodules and nontumorous tissue from 35 cases of mutiple HCCs, 5 (14.3%)and 29 cases (82.9 %) were divided into MO and IM, respectively. Both MO and IM presented simultaneously in 1 patient (2.9%). The integration sites of HBV could be analyzed in 77 nodules from 34 multiple HCCs. Among them, 6 (17. 6%) and 27 cases (79.4%) were divided into MO and IM, respectively. Both MO and IM presented simultaneously in 1 patient (2.9%). The classification results of microsatellite polymorphism test and HBV integration sites analysis demonstrated a significant positive correlation (rs = 0.909, P＜0.001). Nevertheless, neither the classification of microsatellite polymorphism test nor that of HBV integrate sites analysis was correlated with the discrimination according to clinicopathologic and imaging data (rs=0. 133, P=0. 468, rs =0. 262, P=0. 155, respectively). Recurrence in patients in the MO group occurred significantly later than that in IM cases who were diagnosed by clonality analyses (P=0. 001). Conclusion The clonality analysis based on the results of LOH and MSI or assessments of HBV integrate sites is useful for the differential diagnosis of MO and IM and their treatment and prognosis.

AIM: To evaluate the association between apolipoprotein E(apoE) gene polymorphism and sporadic Alzheimer's disease (AD). METHOD: A case-control study was undertaken detecting the polymorphism of apoE by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). RESULTS:(1) The frequencies of ?3/4 genotype and ?4 allele in AD were significantly higher than that in age-matched controls( P

Biopsy ; Histological Techniques ; instrumentation ; methods ; Humans ; Indicators and Reagents ; Paraffin Embedding ; Ultrasonics

The aim of this study was to investigate the effect of Bu-Shen-An-Tai recipe (BSATR) and its two components (Bushen recipe, and Huoxue recipe) on endometrial morphology during peri-implantation in superovulated mice. Mice were randomly divided into five groups, including the normal (N), model (M), Bushen (BS), Huoxue (HX) and Bu-Shen-An-Tai (BH) groups. The uteri were collected on day 4 of pregnancy, and the endometrium thickness, microvessel density (MVD) and number of pinopodes observed. Compared with the M group, the endometrial thickness in the BS, HX and BH groups was significantly increased and there was a significant difference in endometrial thickness between the BS and the BH groups. The mean MVD was significantly lower in the M group than in the N group, and there was a significant increase in MVD in the BS, HX and BH groups as compared with the M group. Compared with the M group, the pinopode scores in the endometrium were significantly increased in the HX and BH groups; and the BS group had significantly higher pinipode scores than the HX and BH groups. In conclusion, the results of the present study demonstrated that the recipes (Bushen, Huoxue and BSATR) could improve the endometrial environment by regulating the endometrial thickness, MVD and the number of pinopodes at the window of implantation. Moreover, the Huoxue recipe and the BSATR were more efficient than the Bushen recipe, with the BSATR tending to have the most beneficial effects.

Quite recently,among new emerging contaminants,pharmaceutical and personal care products(PPCPs)and their active metabolites are an emerging environmental issue,due to their presence in the aquatic environment and potential for impacts on wildlife and humans.Carbamazepine is one of the most frequently and at the relatively high concentration levels detected pharmaceuticals in surface water and even in drinking water.Moreover,this drug has displayed high chronic ecotoxicity.A strain of carbamazepine-degrading bacterium was isolated from activated sludge treating pharmaceutical wastewater in Suzhou,China.It was identified as Acinetobacter sp.HY-7,based on biochemical test,16S rRNA and gyrB gene se-quence analysis.Strain HY-7 could grow in liquid mineral salt medium with carbamazepine as sole source of carbon,nitrogen and energy.HPLC analysis revealed the carbamazepine degradation percentage by HY-7 after 10 days was 48% at pH 6.0 and 25?C.Among carbamazepine and the similar structure compounds,in-dole,catechol,naphthalene,anthracene could also be utilized by strain HY-7 for growth,which exhibited a very broad substrate profile.

Objective To study the effects of nitric oxide synthase(NOS) and nitric oxide(NO) in post-asphyxial renal injury in neonatal rats.Methods Forty-eight Wistar neonatal rats were randomly divided into 4 groups:controls,2 h,24 h and 48 h post-asphyxia groups (12 in each group).The rats were decapitated in different times(2 h,24 h and 48 h) after asphyxia for 30 minutes.The renals were dissected to determined the concentrations of NO and NOS.And the scores of renal tubules were measured under light microscope.Results Compared with control group,the levels of NO and NOS significantly increased at 2 h and 24 h after asphyxia.The scores of renal tubules were significant difference at 24 h and 48 h after asphyxia compared to controls.Conclusion These findings suggest NOS and NO may play an important role in the development of post-asphyxia renal injury.

Objective To detect the type of gene mutation of thalassemia in Kunming city.Methods Sixty-three cases highly suspec-tive of thalassemia were determined with the methods of ploymerase chain reaction(PCR) and reverse dot blot(RDB) for the type of gene mutation.Results According to gene analysis,35 cases were final diagnosed from 63 cases suspective of thalassemia.Among the total,4 cases were gene deficiency ?-thalassemia,and 30 cases were gene deficiency ?-thalassemia,and there was 1 case both ?-thalassemia and ?-thalassemia.There were 9 types of gene mutation with 15 gene combinations in 35 samples.The main type of ?-thalassemia was--SEA/??,there were 6 types with 11 gene combinations from the types of genes of ?-thalassemia,the highest incidence of gene mutation was 17 site,including 17 site homozygote,heterozygote and double heterozygote.Conclusions The thalassemia invasion of Yunnan has its characters,and it is valuable to launch further research.In the same patient,there are ?-thalassemia and ?-thalassemia,it signifies that those 2 types should be diagnosed in the same time,to prevent missed diagnosis.

Functional constipation (FC) is a common functional bowel disorder disease that affects life quality of a large number of people. This study aimed to explore the impact of different intensities of electro-acupuncture (EA) treatment for FC patients. Totally, 111 patients with FC meeting the Rome III criteria were randomly assigned to different intensities of EA groups (low and high intensity of EA groups) and medicine-controlled (MC) group. In EA groups, patients were treated with EA at quchi (LI11) and shangjuxu (ST37) bilaterally for 4 weeks, 5 times/week in the first 2 weeks, and 3 times/week in the last 2 weeks. In MC group, 5 mg mosapride citrate was administered orally 3 times/day for 4 weeks. Spontaneous bowel movement frequency each day was recorded using a constipation diary. Self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were used to assess the patients' psychological state. Cortisol (CORT), substance P (SP), and vasoactive intestinal polypeptide (VIP) were evaluated at baseline and at the end of 4 weeks after treatment. As compared with the baseline, there was statistically significant increase in stool frequency every week (P<0.01), but there was no statistically significant difference among the three groups. As compared with the baseline, after 4 weeks of EA therapy, the scores of SDS and serum levels of CORT were decreased significantly in low intensity of EA group (P<0.01), and the serum levels of SP and VIP were increased significantly (P<0.05); the scores of SAS and SDS and serum levels of CORT were decreased significantly in high intensity of EA group (P<0.05), and the serum levels of SP and VIP were increased significantly (P<0.05); the serum levels of CORT and VIP were increased significantly in MC group (P<0.05). As compared with MC group, after 4 weeks of treatment, the serum levels of SP were signifcicantly increased in low intensity of EA group (P<0.01). Low and high intensities of EA could increase the stool frequency, improve the FC patient's anxiety and depression, reduce the serum levels of CORT, and increase the serum levels of SP and VIP effectively. It is concluded that both low and high intensities of EA are effective for FC patients, but there is no significant difference between the low and high intensities of EA.

Objective To investigate the effects of ulinastatin (UTI) combined with magnesium isoglycyrrhizinate (MgIG) on the expression of transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF) in lung tis?sue of rats with pulmonary fibrosis induced by bleomycin (BLM). Methods Ninety Wistar rats were randomly divided into five groups: BLM group, methylprednisolone (MTH) group, UTI group, MgIG group and UTI combined with MgIG (UTI+MgIG) group, n=18 for each group. The rat model of pulmonary fibrosis was established by injecting bleomycin through tra?chea in five groups. Twenty-four hours after treatment with BLM,rats were treated with normal saline every day in BLM group, and rats were treated by corresponding drugs in other groups. Six rats of each group were killed at the 7th,14th and 28th day respectively. The pathological changes of alveolitis and pulmonary fibrosis were evaluated by HE staining, and ex?pression levels of TGF-β1 and CTGF in lung tissues were detected by immunohistochemistry method. Results (1) Com?pared with BLM group, the degree of alveolitis and pulmonary fibrosis was reduced in other groups. There was significant dif?ference in alveolitis at the 7th and 14th day between UTI+MgIG group and BLM group. And there was significant difference in pulmonary fibrosis at the 14th and 28th day between UTI+MgIG group and BLM group (P<0.05). (2) Compared with BLM group, the expression levels of TGF-β1 and CTGF were decreased in other groups. In UTI+MgIG group, the expres?sion levels of TGF-β1 were significantly lower at the 7th and 14th day compared with those in UTI group and MgIG group, and which were significantly lower at the 28th day than those in MTH group, UTI group and MgIG group (P<0.05). The ex?pression levels of CTGF were significantly lower at the 7th day in UTI + MgIG group than those in UTI group and MgIG group, and which were significantly lower at the 14th and 28th day than those in MTH group, UTI group and MgIG group (P<0.05). Conclusion The combination of UTI and MgIG can alleviate alveolitis and fibrosis in BLM-induced pulmonary fibrosis rats, which might related with the down-regulation of TGF-β1 and CTGF expressions.