Objective To investigate the effects of P-selectin gene knockout on the biological characteristics of mice. Methods P?selectin knockout (PKO) mice and C57BL/6 mice were housed in SPF environment. To make sure that the mice were pure PKO mice by gene identification. To determine the general condition, the activity status, reproduction of P?selectin knockout mice were observed and tested. HE staining was used to observed the histological morphology and struc?tures of 6?week?old and 18?week?old P?selectin knockoutout mice. Results PKO mice and C57 mice have similar multiplica?tion, there was no significant difference in reproduction and blood routine test. The stuctures of liver, spleen, lung and kid?ney were normal. Conclusions P?selectin knockout has no significant effects on reproduction, blood routine test and major organs. This research provides animal model theoretical basis for further study on the effects of P?selection in diseases.

Objective To investigate the effect of PNS on malignant melanoma and the expression of connexin32 in melanoma. Methods The spontaneous and experimental lung metastasis models of B16 melanoma were used to investigate the inhibitory effect of PNS on tumor growth and metastasis. The expression of connexin in melanoma were detected by immunohistoehemistry. Results (1) PNS can obviously inhibit the growth of B16 melanoma. The inhibition rate of the 480mg/kg PNS group was 50. 85%. (2) PNS can obviously inhibit the lung metastasis of B16 melanoma. The number of tumor colonies in lung of the 240 mg/kg PNS group and 480 mg/kg PNS group were lower than that in the negative control group. ( 3 ) The expression of connexin32 in melanoma was detected by immunohistochemistry:PNS could up-regulate the expression of connexin32 in membrane of melanoma. Conclusion PNS can inhibit malignant melanoma growth and metastasis and could also up-regulate the expression of connexin32 in membrane of melanoma.

OBJECTIVEThis study investigated the influence of different designs and porcelain/glaze firing on the marginal and internal fit of three kinds of computer aided design/computer aided manufacturing (CAD/CAM) zirconia ceramic implant-supported crowns.

METHODSThree groups of zirconia ceramic implant-supported crowns with different designs were produced from copings by using a Cercon CAD/CAM system (n = 8). The first two groups comprised double-layer crowns (zirconia coping + veneer) with regular (Group A) and full circumferential zirconia-collar marginal designs (Group B). The third group was composed of anatomic single-layer zirconia crowns without cores (Group C). Initially, the marginal and internal gaps of the copings and crowns were individually replicated by light-body silicon and then measured by micro-computed tomography scanning before and after porcelain/glaze firing. Five measurements were employed: vertical marginal gap (MG); horizontal marginal discrepancy (HMD); chamfer area (CA); axial wall (AW); and axial-occlusal transition area (AOT). Statistical analyses were performed by SPSS 17.0.

RESULTSHMD measurements in Group A were statistically higher than those in Groups B and C (P < 0.05), regardless of whether the values were obtained before or after porcelain/glaze firing. By contrast, the HIMD measurements in Groups B and C showed no significant difference (P > 0.05). Moreover, no differences were noted in MG, CA, AW, and AOT among the three groups (P > 0.05). All the measurements in the three groups showed no significant change after porcelain/glaze firing (P > 0.05), except for MG in Group A, which significantly decreased (P < 0.05).

CONCLUSIONThe marginal fits of the double-layer crowns with full circumferential zirconia-collar and the anatomic single-layer zirconia crowns were superior to that of the double-layer crowns with regular margins. The MG of the crowns with regular margins was obviously influenced by porcelain firing.

Computer-Aided Design ; Crowns ; Dental Porcelain ; Dental Prosthesis Design ; X-Ray Microtomography ; Zirconium

Objective:To clone and express the full length cDNA of human CD38. Methods:The full length cDNA of the human CD38 antigen was amplified from total RNA of Daudi cell by RT-PCR, and it was inserted into pGEM-T. The validity on the sequences was confirmed by automatic DNA sequencing. Inserting the valid CD38 gene into pcDNA3.1(+) plasmid to obtain recombinant mammalian expression vector pcDNA3.1(+)/CD38Z; Using lipofectin gene transfer technique system, recombinant expression vector containing CD38 gene was transfected into COS7 cells. The expression of CD38 molecules on the surface of COS7 cells was detected by FACS and immunohistochemical technique. Results:DNA sequencing showed that the cloned full length cDNA sequence was identical with reported. The result of FACS and immunohistochemical technique indicated that CD38 molecules were expressed on the surface of COS7 cells. Conclusion:The full length cDNA of human CD38 is obtained, recombinant mammalian expression vector pcDNA3.1(+)/CD38Z is successfully constructed, and the CD38 molecules is expressed on the surface of COS7 cells,this may facilitate studies on the biochemistry and function of CD38 antigen.

Objective To investigate the inhibitory effect of Lycium barbarum polysaccharide ( LBP) on the tumor growth and metastasis in MMTV?PyMT mouse model of breast cancer. Methods The population of MMTV?PyMT trans?genic mice was expanded and identified. 8?week old MMTV?PyMT?positive female mice were randomly divided into LBP group and control group, 8 mice in each group. The mice of LBP group were given LBP treatment (50 mg/kg, i. p. ), and the control group was given normal saline in the same volume, once every 2 days for 4 weeks. The tumor size was measured every two days. The mice were killed at 4 weeks after treatment, the lungs were removed and fixed in Bouin′s solution to observe the number of metastatic nodules, and tumor tissues were used for immunohistochemical examination of tumor cell proliferation and vascular density. Results The tumor formation rate was 100% in the MMTV?PyMT?positive mice. The tumor weight of LBP group was 4?208 ± 0?4463 g, significantly lower than the 6?477g ± 0?3724 g in the control group (P<0?005). The number of pulmonary nodules of the LBP group was 12 ± 1?155, significantly less than that of the control group (20 ± 2?745) (P<0?05). The immunohistochemical examination using Ki67 and CD31 staining showed that tumor cell proliferation and microvessel density of the LBP group were significantly less than the NS group. Conclusions LBP inhibits breast cancer growth and metastasis through the inhibitory effect on tumor growth and metastasis, inhibition of tumor cell proliferation and angiogenesis in MMTV?PyMT mice. These mice can be used as an ideal model for studies on antitu?mor drug development for the treatment of breast cancer lung metastasis.

[Objective] To investigate the effect of P-selectin on the intestinal tumorigenesis in the 15,24-week-old ApcMin/+ mice.[Methods] Male ApcMin/+ mice were mated with female P-selectin knockout (P-sel-/-) mice to generate AMin/+Ps-/-mice.The diameters and numbers of the intestinal tumors in the intestines of ApcMin/+ and AM/+ps-/-mice were measured using an inverted microscope.The tumor volumes were measured using the following equation:volume =0.52 × (length × width2).[Results] There were no significant difference between the volume and number of intestinal tumor in 15-week-old ApcMin/+ mice and 15-week-old A+ P-mice.The volume and number of intestinal tumor were significantly increased in 24-week-old A+P-mice compared to 24-weekold ApcMin/+ mice.P-selectin deletion significantly prolonged the survival time of ApcMin/+ mice.[Conclusions] P-selectin deletion promotes the intestinal tumorigenesis in the 24-week-old ApcMin/+ mice.

OBJECTIVETo study the role of Slit-Robo signaling in the proliferation of human mucoepidermoid carcinoma Mc3 cells.

METHODSWe measured the expressions of Slit2 and Robo1 proteins in human mucoepidermoid carcinoma Mc3 cells using immunohistochemistry and flow cytometry. To test the role of Slit-Robo signaling in the proliferation of the cells, we treated the cells with the monoclonal antibody R5 against Robo1 receptor extracellular domain and observed the changes in the cell proliferation by cell counting and colonogenic assay; the expression of proliferating cell nuclear antigen (PCNA) in the cells following the treatment was measured with flow cytometry.

RESULTSTreatment of Mc3 cells with the monoclonal antibody R5 caused significantly suppressed cell growth and proliferation and obviously lowered the expression of PCNA.

CONCLUSIONSlit-Robo signaling can suppress the proliferation of Mc3 cells possibly by up-regulating the expression of PCNA.

Carcinoma, Mucoepidermoid ; pathology ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Intercellular Signaling Peptides and Proteins ; metabolism ; Nerve Tissue Proteins ; metabolism ; Proliferating Cell Nuclear Antigen ; metabolism ; Receptors, Immunologic ; metabolism ; Salivary Gland Neoplasms ; pathology ; Signal Transduction

Objective To study the effect of atrial natriuretic peptide(ANP)deletion on melanoma growth. Methods A subcutaneous xenotransplanted melanoma model was established in ANP knockout mice and C57BL/6J mice. The tumor volume was measured at the sixth day after establishment of the subcutaneous transplantation. Tumor cell proliferation and tumor-induced angiogenesis were detected by immunohistochemical staining. Results The volume and weight of xenotransplanted melanoma were significantly decreased in the ANP knockout mice compared with those in the C57BL/6J mice. The proliferative tumor cells and microvessel density were significantly decreased in the tumor tissues of ANP knockout mice compared with those in the C57BL/6J mice. Conclusions ANP deletion significantly suppresses xenotransplanted melanoma growth through inhibiting the tumor cell proliferation and angiogenesis.

Objective To investigate the role of atrial natriuretic peptide (ANP) in lung metastasis of melanoma. Methods Melanoma B16F10 cells were intravenously injected into ANP knockout mice and C57BL／6J mice. After three weeks, the mice were sacrificed, and the lungs were removed, embedded, and examined by pathology using HE staining. The numbers of metastatic foci on the lung surface and micrometastatic foci in the lung tissues were counted. Results The ANP knockout mice displayed fewer metastatic foci on the lung surface and less micrometastatic foci in the lung tissues of ANP knockout mice than in the C57BL／6J mice. Conclusions ANP deletion significantly suppresses the metastasis of melanoma in the lung of mice.

Objective:To preliminarily study the effect of Louqin Zhisou decoctions with the mechanism of clearing heat and resol-ving phlegm on the blood level of neutrophil elastase ( NE) in the rat model of acute exacerbation of chronic obstructive pulmonary dis-ease ( AECOPD) . Methods:The rat model of AECOPD was established by passive cigarette smoking, intratracheal instillation of li-popolysacchricle ( LPY) and intranasal instillation of staphylococcus aureus. Totally 60 AECOPD rats were randomly divided into 3 groups, the model control group (n=20), ambrohexel group (n=20), and Louqin Zhisou decoctions group (n=20). NE was detec-ted by ELISA. Results:Compared with that before the treatment, NE in ambrohexel group and Louqin Zhisou decoctions group was de-creased significantly(P<0. 01). Conclusion:Clearing heat and resolving phlegm method probably can decrease NE by reducing air-way mucus hypersecretion and obstruction in AECOPD rats.