Biomedical subjects

M Xuan

Publications and source records attributed to M Xuan.

7 recordsLinked to original sources

PubMed2006

Odontogenic tumours: a retrospective study of 1642 cases in a Chinese population.

A total of 1642 odontogenic tumour cases retrieved from the files of the College of Stomatology, Sichuan University, China were retrospectively analyzed for gender, age, tumour site and relative frequency of various types, and the data compared with that of previous reports. The final diagnosis in each case was based on the WHO 2005 histopathological classification of odontogenic tumours. Of these tumours 1592 (97.0%) were benign and 50 (3.0%) were malignant. Ameloblastoma (40.3%) was the most frequent type, followed by keratocystic odontogenic tumour (35.8%), odontoma (4.7%) and odontogenic myxoma (4.6%). The mean age of the patients was 32.1, with a wide range (3-84 years). The male-female ratio and maxilla-mandible ratio were 1.4:1 and 1:4.0, respectively. Ameloblastoma and keratocystic odontogenic tumours, important indications of extensive surgical procedures, are not considered rare in this Chinese population, whereas odontoma is uncommon.

Adolescent↗

PubMed2000

[Immunohistochemical findings on liver tissue in patients with hepatitis C].

OBJECTIVE: To investigate the distributions and infer relations of HCV antigens in the liver tissues. METHODS: Immunohistochemical techniques as polyclonal antibody to HCV, monoclonal antibody to HCV - NS3 and monoclonal antibody to HCV - NS5 were used to detect HCV antigens in 107 patients with hepatitis C. RESULTS: HCV antigens in liver tissues were identified on these three kinds of antibodies. The positive rates were 38.3%, 28.0% and 52.3% respectively. The positive granules were located in the cytoplasma of liver cells. The distributions of positive cells were scattered, diffusive and clustered. No obvious anatomic association was observed between the expression of HCV - NS3 and inflammatory reaction. HCV - NS5 positive cells were more commonly seen around or in the flammatory focci. CONCLUSION: The expressions of various components of HCV were demonstrated in different concentrations. The expressions of HCV - NS5 might be related to the pathogenesis of hepatitis C.

Adult↗

PubMed2000

[Pathologic changes of lymphatic capillaries after injection of U14 cells in rat tongue perineoplastic area].

OBJECTIVE: 1. To establish a model of neck lymphatic metastasis of cancer by injecting tumor cells into the rat tongue; 2. To observe the relationship between pathologic changes of perineoplastic lymphatic in different stages of implanted tumor growth and lymphatic metastasis of tumor cells. METHODS: 60 Kunming rats with injection of 5 x 10(6) U14 tumor cells into each rat tongue were chosen and randomized into 6 groups. In every 5 days, specimens of rat tongues with implanted tumor and neck lymph nodes with possible metastatic tumor cells were removed from each group of rats. Cryosections of rat tongue were processed with a modified enzyme-histochemical staining technique, using 5'-nucleotidase with HE to demonstrate lymphatic capillaries. Attention was paid to pathologic change of lymphatic capillaries in perineoplastic area of rat tongue in different growth stages of implanted tumor. Routing wax sections of lymph nodes processed with HE staining were examined under light microscopy to determine whether there were any metastasis tumor cells. RESULTS: 1. Metastasis to neck lymph nodes could be observed 15 days later after injection of U14 tumor cells into rat tongue. The situation of metastasis of lymph nodes varied greatly from tumor cells in bundle within marginal sinus to complete occupation of lymph nodes by U14 cells. 2. Tumor cells penetrated the lymphatic capillary by passing singly or in clumps between endothelial cells or through some destroyed endothelia. A great number of lymphatic with dilated cavity was found nearby the tumor tissue which facilitated tumor cells to enter the lymphatic cavity. 3. There were much more amount of lymphatic capillaries with dilated cavity around tumor mass comparing with that of normal tongue of the control group rats, and the number of lymphatic capillaries with opening cavity tend to increase with growth of implanted tumor. CONCLUSION: Direct and objective view of lymphatic capillaries can be obtained by means of the modified enzyme-histochemical staining technique, using 5'-nucleotidase with HE to demonstrate lymphatic capillaries; A great number of lymphatic capillaries with dented cavity in normal physical state are forced to be dilated during process of tumor growth, thus in turn increase the possibility for tumor cells to penetrate the lymphatic capillary by passing singly or in clumps between endothelial cells.

Animals↗

PubMed1999

[Study of superinfection of HBV and HCV].

OBJECTIVES: To understand the situation in hepatitis B patients coinciding with HCV and to explore its influence on HCV on the replication of HBV. METHODS: Using ELISA, 712 hepatitis B patients were tested for serum anti-HCV and markers of HBV. RESULTS: Of the 712 patients, anti-HCV positive rate was 14.47% with the highest 48.98% in patients with severe hepatitis and the lowest 3.25% in patients with acute hepatitis. Markedly different anti-HCV positive rates (P < 0.001) in patients of different clinical stages were discovered. The more severe the case with longer the course, the higher the anti-HCV positive rates. In patients with superinfection of HBV and HCV, serum HBsAg, HBeAg and anti-HBcIgM positive rates were lower than those in patients with hepatitis B (P < 0.001, P < 0.001 and P < 0.05) but the anti-HBe positive rates were higher. All the differences showed an obvious statistical significance. CONCLUSION: Hepatitis B coinciding with HCV infection is responsible for the deterioration of the disease and towards its formation of its chronic phase as well as for the inhibition of HBV replication.

Adolescent↗

PubMed1999

[Study on hepatitis G virus infection].

OBJECTIVE: To find out the situation of HGV infection in Shandong Province, and to explore the relations between HGV infection and HCV or HBV infection. METHODS: Enzyme linked immunosorbent assay (ELISA) was used to determine the serum anti-HGV in 1,082 patients with viral hepatitis, 77 patients with non A-E hepatitis and 361 blood donors. RESULTS: 53 patients whose serum anti-HGVs were positive (positive rate: 3.49%) were noticed. The anti-HGV positive rate (8.93%) in patients with Hepatitis C was remarkably higher than that (3.32%) in patients with Hepatitis B (chi 2 = 8.80, P < 0.01). The anti-HGV positive rate (4.82%) in patients with chronic hepatitis was significantly higher than that (0.79%) in patients with acute hepatitis (chi 2 = 10.79, P < 0.01). The anti-HGV positive rate (8.00%) in patients with severe hepatitis was obviously higher than that in patients with acute hepatitis (chi 2 = 10.23, P < 0.01). CONCLUSION: The manifestations of HGV infection can be expressed as virus-carriers, subclinical infection or various clinical types. Patients with Hepatitis C were more subjective to be overlapped with HGV than the patients with Hepatitis B; moreover, HCV or HBV infection superinfected with HGV is associated with exacerbation of patients' condition and the formation of chronic infection.

Adolescent↗

PubMed1998

Odontogenic tumors. A demographic study of 759 cases in a Chinese population.

Seven hundred fifty-nine cases of odontogenic tumors retrieved from the files of College of Stomatology, West China University of Medical Sciences were classified according to the World Health Organization's Histological Classification of Odontogenic Tumors and compared with similar reports from other countries. Among these cases, 93.9% of the tumors were benign and 6.1% were malignant. Ameloblastomas predominated (58.6%) with a predilection for the mandible, while odontomas, generally regarded as the most frequent odontogenic tumor in North America, only accounted for 6.7%, the fourth most common tumor in this series. The mandible and the maxilla were divided into eight anatomic regions, and the distribution of each odontogenic tumor type amongst these regions was recorded. The relative incidence of each tumor type, patient age and gender were also compared with data from other selected large series. Geographic differences were noted in the relative incidence of ameloblastoma, odontoma and malignant odontogenic tumors among the Chinese/African, North American and Turkish/German groups. Ameloblastoma and malignant odontogenic tumors are not considered rare in a Chinese population.

Adolescent↗

PubMed1998

[Study of HDV infection in Shandong province].

To understand the situation of HDV infection in Shandong province and to explore the relationship between HDV and HBV infections, 2681 samples infected with HBV were tested for serum anti-HDV with enzyme linked immunosorbent assay, in Shandong. Among them, 207 (7.72%) were found to be anti-HDV positive. Anti-HDV positive rates in HBsAg carriers and in hepatitis B patients were 3.16% and 13.15%, respectively. A significant difference (P < 0.001) was noticed between the two groups. In the second group, anti-HDV positive rates in patients with chronic active hepatitis and severe hepatitis were both higher than those in patients with acute hepatitis and chronic persistent hepatitis and the difference was significant (P < 0.001). The longer the history and the more severe the condition the higher of the anti-HDV positive rate was seen. The results indicated that the combined and over-lapping HDV infections were both responsible for the chronic status of hepatitis B and its deterioration.

Adolescent↗