Evidence of soluble proteins binding adriamycin by affinity chromatography

Summary The presence in various tissues of soluble proteins binding adriamycin is evidenced by affinity chromatography.     

Post-Normal Science, the Precautionary Principle and the Ethics of Integrity

Present laws and regulations even in democratic countries are not sufficient to prevent the grave environmental threats we face. Further, even environmental ethics, when they remain anthropocentric cannot propose a better approach. I argue that, taking in considerations the precautionary principle, and adopting the perspective of post-normal science, the ethics of integrity suggest a better way to reduce ecological threats and promote the human good globally. This revised version was published online in July 2006 with corrections to the Cover Date.     

Acoustic ecology of an anuran assemblage in the arid Caatinga of northeastern Brazil

Differences in advertisement calls and calling sites are important mechanisms that regulate interactions in anuran assemblages. Individuals might have preferences for ranges of acoustic parameters and calling sites that reduce overlap and ensure coexistence. Herein, acoustic and ecological data were used to investigate the relationships among 12 anurans that co-occur in temporary ponds in the Caatinga, Cabaceiras municipality, Paraíba state, Brazil. Anurans exhibited calling activity correlated with rainfall, but were also spatially dispersed. High overlap levels in calling microhabitats and acoustic parameters were observed, especially among pairs of closely related species. Analysis of null models showed a lack of structure in the spatial and acoustic niche, indicating the lack of detected competition. Results suggest that the calling activity of the species is strongly influenced by rainfall, moreover, the temporal partition appears to ensure coexistence. Finally, strong historical effects were detected in Leiuperinae, Leptodactylidae and in the partition Hylidae–Leptodactyliformes.     

Regulation of DNA methylation of Rasgrf1.

In mammals, DNA is methylated at cytosines within CpG dinucleotides. Properly regulated methylation is crucial for normal development. Inappropriate methylation may contribute to tumorigenesis by silencing tumor-suppressor genes or by activating growth-stimulating genes. Although many genes have been identified that acquire methylation and whose expression is methylation-sensitive, little is known about how DNA methylation is controlled. We have identified a DNA sequence that regulates establishment of DNA methylation in the male germ line at Rasgrf1. In mice, the imprinted Rasgrf1 locus is methylated on the paternal allele within a differentially methylated domain (DMD) 30 kbp 5' of the promoter. Expression is exclusively from the paternal allele in neonatal brain. Methylation is regulated by a repeated sequence, consisting of a 41-mer repeated 40 times, found immediately 3' of the DMD. This sequence is present in organisms in which Rasgrf1 is imprinted. In addition, DMD methylation is required for imprinted Rasgrf1 expression. Together the DMD and repeat element constitute a binary switch that regulates imprinting at the locus.     

Different patterns of peripheral migration by memory CD4+ and CD8+ T cells

Infections localized to peripheral tissues such as the skin result in the priming of T-cell responses that act to control pathogens. Activated T cells undergo migrational imprinting within the draining lymph nodes, resulting in memory T cells that provide local and systemic protection. Combinations of migrating and resident memory T cells have been implicated in long-term peripheral immunity, especially at the surfaces that form pathogen entry points into the body. However, T-cell immunity consists of separate CD4(+) helper T cells and CD8(+) killer T cells, with distinct effector and memory programming requirements. Whether these subsets also differ in their ability to form a migrating pool involved in peripheral immunosurveillance or a separate resident population responsible for local infection control has not been explored. Here, using mice, we show key differences in the migration and tissue localization of memory CD4(+) and CD8(+) T cells following infection of the skin by herpes simplex virus. On resolution of infection, the skin contained two distinct virus-specific memory subsets; a slow-moving population of sequestered CD8(+) T cells that were resident in the epidermis and confined largely to the original site of infection, and a dynamic population of CD4(+) T cells that trafficked rapidly through the dermis as part of a wider recirculation pattern. Unique homing-molecule expression by recirculating CD4(+) T effector-memory cells mirrored their preferential skin-migratory capacity. Overall, these results identify a complexity in memory T-cell migration, illuminating previously unappreciated differences between the CD4(+) and CD8(+) subsets.     

从“火”箭到卫星——意中空间科技合作回眸与展望

 意大利作为世界重要航天国家和欧洲航天局主要成员国,与中国有着久远的人文与科技交流,为人类探索太空的许多里程碑任务做出了不可忽略的贡献。追溯了意大利悠久的空间科技发展史和诸多亮点,包括中国火药对其“火”箭技术发展的促进作用;归纳了意-中在载人航天、地震空间电磁监测、空间科学卫星等领域开展的重要合作以及系列丰硕的成果;并指出意中科技文化交流源远流长,共同促进了文明的进步,如“西学东渐”等自然和社会科学知识的传播活动等。展望未来,在“一带一路”倡议的推动下,意中携手,可在探索浩瀚宇宙奥秘征程中为人类做出新的贡献。