Role of macrophages in the mechanism of specific entrapment of sensitized lymphocytes in lymph nodes containing antigen

A study was made of the participation of macrophages in the phenomenon of specific trapping of lymphocytes activated with the antigen in the lymph nodes containing the same antigen. Administration of peritoneal macrophages which phagocytized in vitro sheep erythrocytes (as well as of erythrocytes alone) led to specific trapping of lymphocytes in the regional lymph nodes. Preliminary treatment of macrophages loaded with the antigen with antierythrocytic serum decreased the lymphocyte trapping. A supposition was put forward that lymphocytes with receptors on their surface were bound on the macrophage membrane into which the antigen molecules were incorporated.     

兽人高速运载车——铁皮卡车

战棋游戏在西方国家是一种十分流行的实战游戏,品牌众多且各有特色。近期这种游戏也在国内开始兴起,但是题材多为科幻类、奇幻类等,不过由于它包含了模型和游戏两方面的特性,而且它们的造型丰富,改造空间大,所以很快被大家所接受。目前国内最常见的是英国老牌战棋公司Gamesworkshop（以下简称GW）的战棋产品。     

Effects of optimism, pessimism, and trait anxiety on ambulatory blood pressure and mood during everyday life

An assay for the neutral glycosphingolipid, globotriaosylceramide (Galalpha1-4Galbeta1-4Glcbeta1-1Cer; GL-3), was developed based on the B subunit of Escherichia coli verotoxin (VTB). The VTB gene was isolated, overexpressed in E. coli, and purified by a single immunoaffinity chromatographic step using a monoclonal anti-VTB IgG-agarose column. Purified recombinant VTB was used to develop an enzyme-linked immunosorbent assay (ELISA) to determine the GL-3 concentrations in plasma and tissue extracts from normal individuals and patients and mice with alpha-galactosidase A deficiency (human Fabry disease). The mean (+/-1 SD) plasma GL-3 concentrations in affected male and female heterozygotes with Fabry disease were 12.6 +/- 3.7 and 1.1 +/- 0.7 microg/ml, respectively, whereas normal individuals had 0.9 +/- 0.4 microg/ml. In 5- to 6-month-old mice with alpha-galactosidase A deficiency, the average GL-3 concentrations in spleen, kidney, liver, heart, and plasma were 2790 +/- 400, 1100 +/- 93, 378 +/- 67, and 196 +/- 28 ng/mg wet wt and 5. 1 +/- 2.0 microg/ml, respectively, whereas tissues from wild-type mice contained very low or undetectable GL-3 levels. This ELISA assay should prove useful for determining the GL-3 levels, as well as for monitoring the effectiveness of therapeutic endeavors in patients with Fabry disease.     

Photo-oxidative stress down-modulates the activity of nuclear factor-kappaB via involvement of caspase-1, leading to apoptosis of photoreceptor cells

The mechanisms of photoreceptor cell death via apoptosis, in retinal dystrophies, are largely not understood. In the present report we show that visible light exposure of mouse cultured 661W photoreceptor cells at 4.5 milliwatt/cm2 caused a significant increase in oxidative damage of 661W cells, leading to apoptosis of these cells. These cells show constitutive expression of nuclear factor-kappaB (NF-kappaB), and light exposure of photoreceptor cells results in lowering of NF-kappaB levels in both the nuclear and cytosolic fractions in a time-dependent manner. Immunoblot analysis of IkappaBalpha and p50, and p65 (RelA) subunits of NF-kappaB, suggested that photo-oxidative stress results in their depletion. Immunocytochemical studies using antibody to RelA subunit of NF-kappaB further revealed the presence of this subunit constitutively both in the nucleus and cytoplasm of the 661W cells. Upon exposure to photo-oxidative stress, a depletion of the cytoplasmic and nuclear RelA subunit was observed. The depletion of NF-kappaB appears to be mediated through involvement of caspase-1. Furthermore, transfection of these cells with a dominant negative mutant IkappaBalpha greatly enhanced the kinetics of down modulation of NF-kappaB, resulting in a faster photo-oxidative stress-induced apoptosis. Taken together, these studies show that the presence of NF-kappaB RelA subunit in the nucleus is essential for protection of photoreceptor cells against apoptosis mediated by an oxidative pathway.     

Sequence elements required for apolipoprotein B mRNA editing enhancement activity from chicken enterocytes

Mammalian intestinal apolipoprotein B (apoB) mRNA edits codon 2153 from CAA in apoB100 mRNA to a stop codon (UAA) in apoB48 mRNA. By contrast, chicken intestinal apoB mRNA contains a CAA codon at the corresponding site, but is not edited. Chicken enterocyte S100 extracts fail to edit mammalian apoB RNA, but contain factor(s) which enhance the mammalian enterocytes editing activity. By converting the chicken apoB mooring sequences to the conserved mammalian sequences, the study confirmed that this 11-nucleotide stretch was necessary and sufficient for minimal RNA editing. Using rat and chicken apoB chimeric constructs, the study revealed that mammalian apoB sequences were required for editing enhancement. In concert with the 29-nucleotide conserved cassette, the 5' rat apoB element (nucleotides 6615-6629) increased editing at C-6666, and was necessary for editing enhancement of chicken enterocyte S100 extracts. Similarly, the 3' rat apoB element (nucleotides 6726-6752) was required for editing enhancement of chicken enterocyte S100 extracts, but to a lesser extent in efficiency, compared to the 5' region. In conclusion, this study identified the sequences required for editing enhancement activity from chicken enterocyte S100 extracts.