ABSTRACT
As a special mode of tumor metastasis, perineural invasion has been paid more and more attention. It is closely related to prognosis, recurrence and metastasis of tumor after surgery. As the most common malignancy of the biliary tract, perineural invasion is also an inde-pendent prognostic risk factor for gallbladder cancer due to its anatomical location, lymphatic reflux, blood perfusion and innervation. However, there are few studies on perineural invasion in gallbla-dder cancer, especially on its mechanism. By analyzing the general situation and recent progress of perineural invasion in gallbladder cancer, the authors mainly introduce the perineural invasion mechanism, perineural invasion rate of gallbladder cancer, relationship between perineural invasion and the clinical pathologic characteristic, the correlation with the prognosis, relationship with surgi-cal procedures and postoperative adjuvant therapy.
ABSTRACT
In order to induce male sterility of Brassica campestris L. subsp. chinensis Makino var. parachinensis, we introduced the chimeric pTA29-barnase gene into it by Agrobacteriumtume faciens transformation. We obtained the transgenic plants, and determined them by PCR, Southern blotting and RT-PCR analysis. Results indicated that the RNase (barnase) gene had been transferred into genome of plant, and its expression level was different among transformation plants. All transgenic plants were male sterile; there was no vigor or a little pollen without fertility in the anther of transgenic plants. The transgenic plants failed to produce seeds under the condition self-control pollination, but hybrid seeds set were obtained when these transgenic plants were cross-pollinated artificially with normal pollen from untransformed plants. Progeny from cross-pollinated maintainer line with transgenic plants segregated in the 1:1 for male sterility and male fertility, and these phenotypes corresponded directly to the presence or absence of the chimeri TA29-barnase gene. The male fertile plants of co-separated progenies could die by spraying 10 mg/L PPT in cotyledon seedling stage. The hybrid F1 between male sterility and other varieties showed heterosis in yield and growth. All these show that it is an efficient method to induce male sterility in Brassica campestris L. subsp. chinensis Makino var. parachinensis by TA29-barnase ene, there is potential on heterosis breeding of Brassica campestris L. subsp. chinensis Makino var. parachinensis.
Subject(s)
Agrobacterium tumefaciens , Genetics , Brassica , Genetics , Gene Transfer Techniques , Genes, Plant , Genetics , Plant Infertility , Genetics , Plants, Genetically Modified , Genetics , Ribonucleases , Genetics , Transformation, GeneticABSTRACT
It was previously thought that keratinocytes did not express the CD80 and CD86 which provide the most important costimulatory signals for the antigen-specific T-cell activation. The cultured keratinocytes allografts were initially accepted, but eventually, all grafted donor cells were gradually replaced by recipient cells. The precise mechanisms are not very clear. In this study, neonatal murine keratinocytes were cultured for 7 days, the results of flow cytometry and confocal microscopy showed that CD80 could be detected on keratinocytes, while CD86 could not be detected all the time. RT-PCR analysis confirmed this result. The expression level of the CD80 mRNA amplified significantly from day 1 to day 7, as expression of the control beta-actin, but CD86 was not detected. Mixed Lymphocyte Reaction (MLR) showed that keratinocytes cultured with 10% serum for 7 d stimulated effectively allogeneic rather than syngeneic T cell proliferation. This study demonstrated for the first time that costimulatory molecule CD80 can be expressed on keratinocytes in vitro. These data provided an alternative explanation for the ultimate rejection of allogeneic keratinocytes in which keratinocytes act as antigen-presenting cells.