[Standardized diagnosis and treatment of colorectal polyps].

This article explores the standardized management of colorectal polyps, including classification, treatment, follow-up, and preventive control. Corresponding treatment strategies, including endoscopic resection and surgical intervention, are employed for different types of polyps. Currently, there is debate over whether to choose endoscopic resection or surgical intervention for malignant polyps at pT1 stage. Drawing on the latest literature and guidelines, the article elaborates on polyp classification, treatment modalities, follow-up, and preventive measures. Standardized management of colorectal polyps is important for reducing the incidence of colorectal cancer and improving the cure rate of early-stage colorectal cancer.

New differentiation antigens associated with the growth and maturation of B lymphocytes.

Monoclonal antibodies (mAb) NDA3 and NDA4 were generated by hyperimmunizing mice with an alloreactive human T cell clone and fusing the splenocytes with the NS1 myeloma. Immunofluorescence studies indicated that these mAb react with activated, but not with resting T and B lymphocytes or with other types of cells. Immunoprecipitation studies with 125-I-labeled extracts from T and B cell lines demonstrated that the m.w. of the antigen recognized by mAb NDA3 is 36,000 and that of NDA4 is 46,000. Studies on the effect of mAb NDA3 and NDA4 on Epstein Barr Virus-transformed lymphoblastoid B cell lines (LBCL) demonstrated that these antibodies stimulate B cell proliferation and Ig synthesis. The level of expression of NDA3 and NDA4 on the membrane of LBCL is significantly augmented when cells are grown in the presence of recombinant human interferon-beta and gamma and is decreased in the presence of 12-O-tetradecanoyl-phorbol-13-acetate. These observations, in conjunction with the stimulatory effect of mAb NDA3 and NDA4 on the growth and differentiation of LBCL, suggest that these new differentiation antigens, NDA3 and NDA4, may serve as growth factor receptors.

Properties of rat and mouse beta-glucuronidase mRNA and cDNA, including evidence for sequence polymorphism and genetic regulation of mRNA levels.

cDNA clones containing partial sequences for beta-glucuronidase (beta G) were constructed from rat preputial gland RNA and identified by their ability to selectively hybridize beta G mRNA. One such rat clone was used to isolate several cross-hybridizing clones from a mouse-cDNA library prepared from kidney RNA from androgen-treated animals. Together, the set of mouse clones spans about 2.0 kb of the 2.6-kb beta G mRNA. Using these cDNA clones as probes, a genomic polymorphism for DNA restriction fragment size was found that proved to be genetically linked to the beta G gene complex. A fragment of beta G cDNA was subcloned into a vector carrying an SP6 polymerase promoter to provide a template for the in vitro synthesis of single-stranded RNA complementary to beta G mRNA. This provided an extremely sensitive probe for the assay of beta G mRNA sequences. Using either nick-translated cDNA or transcribed RNA as a hybridization probe, we found that mouse beta G RNA levels are strongly induced by testosterone, and that induction by testosterone is pituitary-dependent. During the lag period preceding induction, during the induction period itself, and during deinduction following removal of testosterone, beta G mRNA levels paralleled rates of beta G synthesis previously measured by in vivo pulse-labelling experiments. Genetic variation in the extent of induction affected either the level of beta G mRNA or its efficiency of translation depending on the strain of mice tested.