Atypical mast cell degranulation and focal hydropic degeneration of venular endothelium in diffuse fibrosing alveolitis

Summary Atypical scroll-like and tubular degranulation of mast cells closely associated with focal endothelial hydropic degeneration is reported in human lung from 4 patients with diffuse fibrosing alveolitis in which the predominant abnormality was hyperplasia and desquamation of type 2 pneumocytes.This work was supported by a grant from the National health and Medical Research Council of Australia.     

Molecular evidence for genetic mixing of Arctic and Antarctic subpolar populations of planktonic foraminifers

Bipolarity, the presence of a species in the high latitudes separated by a gap in distribution across the tropics, is a well-known pattern of global species distribution. But the question of whether bipolar species have evolved independently at the poles since the establishment of the cold-water provinces 16-8 million years ago, or if genes have been transferred across the tropics since that time, has not been addressed. Here we examine genetic variation in the small subunit ribosomal RNA gene of three bipolar planktonic foraminiferal morphospecies. We identify at least one identical genotype in all three morphospecies in both the Arctic and Antarctic subpolar provinces, indicating that trans-tropical gene flow must have occurred. Our genetic analysis also reveals that foraminiferal morphospecies can consist of a complex of genetic types. Such occurrences of genetically distinct populations within one morphospecies may affect the use of planktonic foraminifers as a palaeoceanographic proxy for climate change and necessitate a reassessment of the species concept for the group.     

A novel uterine lipocalin supporting pregnancy in equids

Horses, donkeys, and therefore, probably all equids, secrete a nonglycosylated, progesterone-dependent, 19-kDa protein (P19) into the uterine lumen during early pregnancy, and significant quantities of it are taken up by the developing conceptus. Sequence analysis and structural modelling have identified P19 as a lipocalin with greatest similarity to the murine major urinary protein lipocalins. However, lack of strong identity with any particular group of lipocalins and several unusual structural features, including a unique amino acid triplet within one of the invariant domains and an unusual external tryptophan residue, classify it as a new member of the lipocalin family. P19 is therefore likely to be a transport protein involved in supporting early embryonic development. Preliminary evidence using recombinant-derived P19 and fluorescently tagged ligands suggests that it may transport a fatty acid or retinol-like molecule. Although an initial search failed to identify homologues of P19 in other mammals, they may nevertheless exist but are synthesised and secreted in much smaller quantities, making them difficult to detect. Equids appear to need particularly large quantities of the protein during early pregnancy because of the unusually late implantation in this species and the presence of a capsule surrounding the conceptus until about day 23 of gestation.     

信息管理与信息资源管理及知识管理的关系

分别对IM(信息管理)、IRM(信息资源管理)、KM(知识管理)的概念及内涵进行了阐述，比较了三者的联系与区别，进而就三者的关系进行了探讨。     

Chromosome races in Sarcobatus (Sarcobataceae, Caryophyllales)

Sarcobatus Nees., a genus of North American halophytic shrubs, consists of 2 species: S. vermiculatus (Hook.) Torr. ( n = 18, 36), which is widespread in North America, and S. baileyi Cov ( n = 54), endemic to Nevada. Within S. vermiculatus , populations of n = 36 are widely distributed, whereas populations of n = 18 are found only in the Sonoran Desert, northern California, and northwestern Great Plains, locations at the periphery of the species range. Although the chromosome number of n = 18 is apparently a tetraploid, failure to form and n = 27 race intermediate to those of n = 18 and n = 36 suggests than n = 18 S. vermiculatus is of significant age and that it behaves chromosomally as a diploid. Sacrobatus has a long fossil pollen record and endured Pleistocene climatic extremes with little range displacement.     

Multiple self-healing squamous epithelioma is caused by a disease-specific spectrum of mutations in TGFBR1

Multiple self-healing squamous epithelioma (MSSE), also known as Ferguson-Smith disease (FSD), is an autosomal-dominant skin cancer condition characterized by multiple squamous-carcinoma-like locally invasive skin tumors that grow rapidly for a few weeks before spontaneously regressing, leaving scars. High-throughput genomic sequencing of a conservative estimate (24.2 Mb) of the disease locus on chromosome 9 using exon array capture identified independent mutations in TGFBR1 in three unrelated families. Subsequent dideoxy sequencing of TGFBR1 identified 11 distinct monoallelic mutations in 18 affected families, firmly establishing TGFBR1 as the causative gene. The nature of the sequence variants, which include mutations in the extracellular ligand-binding domain and a series of truncating mutations in the kinase domain, indicates a clear genotype-phenotype correlation between loss-of-function TGFBR1 mutations and MSSE. This distinguishes MSSE from the Marfan syndrome-related disorders in which missense mutations in TGFBR1 lead to developmental defects with vascular involvement but no reported predisposition to cancer.