Absence of immunosuppression in DBA/2 mice vaccinated with Trypanosoma cruzi treated with actinomycin-D

The subcutaneous (s.c.) vaccination of DBA/2 mice with 4 weekly doses of 3 x 10(7) living metacyclic forms of T. cruzi, Y strain, obtained from culture in axenic medium and treated for 24 h with actinomycin-D (50 micrograms/10(7) parasites), a drug that promotes an irreversible blockade of the parasite replication, do not induce any detectable degree of humoral and cellular immunosuppression as assessed by a) the production of anti-SRBC antibodies, b) the permanence of delayed cutaneous reaction to T. cruzi antigen, to PPD and DNCB and c) the degree of blastogenic transformation of spleen lymphocytes in the presence of the specific antigen.     

Retinoic acid regulates avian lung branching through a molecular network

Retinoic acid (RA) is of major importance during vertebrate embryonic development and its levels need to be strictly regulated otherwise congenital malformations will develop. Through the action of specific nuclear receptors, named RAR/RXR, RA regulates the expression of genes that eventually influence proliferation and tissue patterning. RA has been described as crucial for different stages of mammalian lung morphogenesis, and as part of a complex molecular network that contributes to precise organogenesis; nonetheless, nothing is known about its role in avian lung development. The current report characterizes, for the first time, the expression pattern of RA signaling members (stra6, raldh2, raldh3, cyp26a1, rarα, and rarβ) and potential RA downstream targets (sox2, sox9, meis1, meis2, tgfβ2, and id2) by in situ hybridization. In the attempt of unveiling the role of RA in chick lung branching, in vitro lung explants were performed. Supplementation studies revealed that RA stimulates lung branching in a dose-dependent manner. Moreover, the expression levels of cyp26a1, sox2, sox9, rarβ, meis2, hoxb5, tgfβ2, id2, fgf10, fgfr2, and shh were evaluated after RA treatment to disclose a putative molecular network underlying RA effect. In situ hybridization analysis showed that RA is able to alter cyp26a1, sox9, tgfβ2, and id2 spatial distribution; to increase rarβ, meis2, and hoxb5 expression levels; and has a very modest effect on sox2, fgf10, fgfr2, and shh expression levels. Overall, these findings support a role for RA in the proximal–distal patterning and branching morphogenesis of the avian lung and reveal intricate molecular interactions that ultimately orchestrate branching morphogenesis.     

一类非单调关联系统的率模可靠性分析

实际的生产和生活中存在着大量的非单调关联系统 ,对其进行可靠性分析就需要有相应的非单调关联系统理论支持 ,现有的率模 (probabilityandfuzzystate ,Profust)可靠性理论仅仅对单调关联系统进行了讨论。因此 ,首先建立了Profust非单调关联系统的相关理论 ,然后针对一类典型的非单调关联系统 (“n中取r至s”系统 )进行了具体的可靠性分析 ,从而在非单调关联系统领域对蔡的Profust可靠性理论进行了进一步的确证和推广     

中国芯片发展现状（四）

阐述了我国芯片产业的现状，介绍了我国自行研制开发的光子芯片、“神芯”芯片、“华厦网芯”、IC卡芯片、3G手机芯片的用途、性能和发展前景。     

供应链中二级分销网络优化设计的随机规划模型

给出供应链中二级分销网络优化设计的机会约束规划模型。模型中将各个分销中心的需求量和各工厂的生产能力设为随机参数，并进一步讨论如何将模型中的机会约束转化为确定性等价类问题。     

Study of the mechanism of inhibition produced by hexoses on histamine release activity of dextran

Zusammenfassung Die Hemmung der Histaminfreisetzung durch Hexosen wurde untersucht. Es gelang, nachzuweisen bzw. graphisch darzustellen, dass ein Zusammenhang zwischen dem Prozentgehalt der Histaminfreisetzung und der Dextrankonzentration besteht, wenn nachLineweaver undBurk analysiert wurde.     

Model of the interaction between trypsin and alpha 2-macroglobulin of porcine serum]

A comparative study of the dissociation into subunits of Porcine alpha2 M, either native or bound to trypsin (Tn), has been carried out in order to determine the modifications of the alpha2 M structure due to the formation of the Tn-alpha2 M complex. Analytical ultra-centrifugation at pH 3.5 shows that the dissociation is smaller when alpha 2 M is bound to trypsin. Electrophoresis in 4% polyacrylamide gels, in presence of 0.1% SDS, of alpha2 M and Tn-alpha2 M incubated in 1% SDS leads to the same conclusion; the enzyme must stabilize the quaternay structure of alpha2 M. In presence of SDS + beta-mercaptoethanol, only a molecular weight (M.W.) 200,000 band is revealed in electrophoresis pattern of native alpha2 M. In the case of reduced Tn-alpha2 M, some other bands of M.W. 100,000, 50,000, 30,000 appear. When trypsin is inactivated by TLCK 100,000 M.W. band is present, accompanied by the 200,000 M.W. band whose intensity is function of the alpha2 M concentration. The 100,000 M.W. band appears therefore characteristic of the formation of the complex which must imply a proteolytic cleavage in the middle of the 100,000 polypeptidic chain of alpha2 M. A model of the complex is proposed in which the enzyme forms a proteic bridge between the two halves of the alpha2 M molecule.