抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

An endothelium-derived 21-residue vasoconstrictor peptide, endothelin, has been isolated, and shown to be one of the most potent vasoconstrictors known. Cloning and sequencing of preproendothelin complementary DNA shows that mature endothelin is generated through an unusual proteolytic processing, and regional homologies to a group of neurotoxins suggest that endothelin is an endogenous modulator of voltage-dependent ion channels. Expression of the endothelin gene is regulated by several vasoactive agents, indicating the existence of a novel cardiovascular control system.

/pdf/a-novel-potent-vasoconstrictor-peptide-produced-by-vascular-4zvh0kyupn.pdf

A novel potent vasoconstrictor peptide produced by vascular endothelial cells.

Vascular endothelial growth factor (VEGF) was purified from media conditioned by bovine pituitary folliculostellate cells (FC). VEGF is a heparin-binding growth factor specific for vascular endothelial cells that is able to induce angiogenesis in vivo. Complementary DNA clones for bovine and human VEGF were isolated from cDNA libraries prepared from FC and HL60 leukemia cells, respectively. These cDNAs encode hydrophilic proteins with sequences related to those of the A and B chains of platelet-derived growth factor. DNA sequencing suggests the existence of several molecular species of VEGF. VEGFs are secreted proteins, in contrast to other endothelial cell mitogens such as acidic or basic fibroblast growth factors and platelet-derived endothelial cell growth factor. Human 293 cells transfected with an expression vector containing a bovine or human VEGF cDNA insert secrete an endothelial cell mitogen that behaves like native VEGF.

https://science.sciencemag.org/content/sci/246/4935/1306.full.pdf

Vascular endothelial growth factor is a secreted angiogenic mitogen

: Successful Software reuse requires the systematic discovery and exploitation of commonality across related software systems. By examining related software systems and the underlying theory of the class of systems they represent, domain analysis can provide a generic description of the requirements of that class of systems and a set of approaches for their implementation. This report will establish methods for performing a domain analysis and describe the products of the domain analysis process. To illustrate the application of domain analysis to a representative class of software systems, this report will provide a domain analysis of window management system software.

/pdf/feature-oriented-domain-analysis-foda-feasibility-study-2zsj0a30fo.pdf

Feature-Oriented Domain Analysis (FODA) Feasibility Study

Because the critical central regions of Active Galactic Nuclei (AGN) and quasars are strongly nonspherical but spatially unresolved, orientation effects have been the source of much confusion. In fact, it now appears that much of the variety in AGN types is just the result of varying orientation relative to the line of sight. We can define an extreme hypothesis,, the straw person model (SPM), in which there are two basic types of AGN: the radio quiets and the radio louds. For each type there is a range in intrinsic luminosity, and the luminosity controls some properties such as the Fanaroff and Riley classes. However, at a given intrinsic luminosity, all other properties such as spectroscopic classification and VLBI component speeds are ascribed to orientation. This model is only a caricature of the unification idea, and is already ruled out on many grounds, but it will be useful for organizing the discussion. I’ll describe what I consider to be convincing evidence that orientation effects are important and widespread. The true situation may be in some sense half way between the SPM and the hypothesis that orientation doesn’t affect classification at aIl. To us optimists, the orienration cup is half full rather than half empty. Although it is too soon to say for sure, the hypothesis that most objects’ classifications would be different if seen from other directions is a tenable one today.

http://www.physics.purdue.edu/%7Emlister/articles/antonucci1993_ann_rev.pdf

Unified models for active galactic nuclei and quasars

The firA200 mutation of E. coli not only renders RNA synthesis thermosensitive but also eliminates the high-level resistance to rifampicin associated with certain mutations in the β subunit of the RNA polymerase. A priori, the firA gene is likely to code for an essential component of the transcription apparatus. The isolation is reported of transducing phages for the firA gene, constructed in vitro by fusing fragments of the E. coli chromosome into a lambdoid bacteriophage. Such phages carry at least two essential genes and are able to suppress both the thermosensitivity and abnormal rifampicin sensitivity associated with the firA200 allele. The finding that some, but not all, of the λfirA phages have a temperature dependent growth defect is discussed.

The firA gene, a locus involved in the expression of rifampicin resistance in Escherichia coli. I. Characterisation of lambdafirA transducing phages constructed in vitro.

The expression of a protein-coding DNA fragment in a microorganism such as Escherichia coli requires that the exogenous DNA segment be inserted precisely in phase with bacterial translation initiation signals. We report the construction of derivatives of the M13 vectors M13mp7 and M13mp701 in which a HindIII site has been inserted, within the N-terminal section of the beta-galactosidase gene, in all three phases of translation. These vectors may thus be used for the expression, under the control of the lac promoter and translation initiation signals, of protein coding DNA segments flanked by a HindIII site. In all cases the insertion of a DNA fragment can be recognized by the abolition of beta-galactosidase activity. These vectors have been used to direct the expression, in E. coli, of a cDNA segment coding for the rabies virus surface glycoprotein. The proteins produced have been shown to react with antisera raised against authentic rabies glycoprotein.

M13 bacteriophage vectors for the expression of foreign proteins in Escherichia coli: the rabies glycoprotein.

Differential display detects host nucleic acid motifs altered in scrapie-infected brain.

Novel products from livestock.

Erratum: An endocrine pathway in the prostate, ERβ, AR, 5α-androstane-3β,17β-diol, and CYP7B1, regulates prostate growth (Proceedings of the National Academy of Sciences of the United States of America (October 15, 2002) 99, 21 (13589-13594) (DOI: 10.1073/pnas.162477299))

Richard Lathe

Papers

The firA gene, a locus involved in the expression of rifampicin resistance in Escherichia coli. I. Characterisation of lambdafirA transducing phages constructed in vitro.

M13 bacteriophage vectors for the expression of foreign proteins in Escherichia coli: the rabies glycoprotein.

Differential display detects host nucleic acid motifs altered in scrapie-infected brain.

Novel products from livestock.

Erratum: An endocrine pathway in the prostate, ERβ, AR, 5α-androstane-3β,17β-diol, and CYP7B1, regulates prostate growth (Proceedings of the National Academy of Sciences of the United States of America (October 15, 2002) 99, 21 (13589-13594) (DOI: 10.1073/pnas.162477299))