RICE‐PAPER PLANT –TETRAPANAX PAPYRIFER

From the 1820s pith became a familiar material in Europe, under the name of rice‐paper, as a raw material for artificial flowers, and as a medium for export paintings from China. The structure of pith sheets was early recognised as different to that of paper, but it was not until 1852 that William Jackson Hooker was able to describe the source plant, as Aralia papyrifera Hook., now Tetrapanax papyrifer (Hook.) K. Koch. Using his consular contacts, Hooker was able to build up a remarkable collection of pith, as raw materials, artificial flowers and Chinese paintings. Many are described and illustrated in this article, in the context of recent work on the history and conservation of pith paintings.     

A system of nomenclature for band patterns of mouse chromosomes

Mouse chromosomes banded by quinacrine mustard staining, by the ASG technique, or by Giemsa staining following trypsinization or chymotrypsinization are described in detail. Three hundred and twelve regions within the mouse karyotype can be distinguished and a simple system of nomenclature is proposed for naming these regions. This nomenclature is applied to discussion of the locations of the breakpoints of twenty translocations and of many specific gene loci.Dedicated to the memory of Dr. Stanley W. Wright, in gratitude for his support of, and interest in, our work.Supported by Cancer Research Funds of the University of California and USPHS Grant HD 04608.     

Dok-2 Adaptor Protein Regulates the Shear-dependent Adhesive Function of Platelet Integrin αIIbβ3 in Mice

The Dok proteins are a family of adaptor molecules that have a well defined role in regulating cellular migration, immune responses, and tumor progression. Previous studies have demonstrated that Doks-1 to 3 are expressed in platelets and that Dok-2 is tyrosine-phosphorylated downstream of integrin α_IIbβ₃, raising the possibility that it participates in integrin α_IIbβ₃ outside-in signaling. We demonstrate that Dok-2 in platelets is primarily phosphorylated by Lyn kinase. Moreover, deficiency of Dok-2 leads to dysregulated integrin α_IIbβ₃-dependent cytosolic calcium flux and phosphatidylinositol(3,4)P₂ accumulation. Although agonist-induced integrin α_IIbβ₃ affinity regulation was unaltered in Dok-2^−/− platelets, Dok-2 deficiency was associated with a shear-dependent increase in integrin α_IIbβ₃ adhesive function, resulting in enhanced platelet-fibrinogen and platelet-platelet adhesive interactions under flow. This increase in adhesion was restricted to discoid platelets and involved the shear-dependent regulation of membrane tethers. Dok-2 deficiency was associated with an increased rate of platelet aggregate formation on thrombogenic surfaces, leading to accelerated thrombus growth in vivo. Overall, this study defines an important role for Dok-2 in regulating biomechanical adhesive function of discoid platelets. Moreover, they define a previously unrecognized prothrombotic mechanism that is not detected by conventional platelet function assays.     

Identifying novel genes in <Emphasis Type="Italic">C. elegans</Emphasis> using SAGE tags

Background  

Despite extensive efforts devoted to predicting protein-coding genes in genome sequences, many bona fide genes have not been found and many existing gene models are not accurate in all sequenced eukaryote genomes. This situation is partly explained by the fact that gene prediction programs have been developed based on our incomplete understanding of gene feature information such as splicing and promoter characteristics. Additionally, full-length cDNAs of many genes and their isoforms are hard to obtain due to their low level or rare expression. In order to obtain full-length sequences of all protein-coding genes, alternative approaches are required.     

Recovery of scrap iron metal value using biogenerated ferric iron

The utility of employing biogenerated ferric iron as an oxidant for the recycling of scrap metal has been demonstrated using continuously growing cells of the extremophilic organism Acidithiobacillus ferrooxidans. A ferric iron rich (70 mol%) lixiviant resulting from bioreactor based growth of A. ferrooxidans readily solubilized target scrap metal with the resultant generation of a leachate containing elevated ferrous iron levels and solubilized copper previously resident in the scrap metal. Recovery of the copper value was easily accomplished via a cementation reaction and the clarified leachate containing a replenished level of ferrous iron as growth substrate was shown to support the growth of A. ferrooxidans and be fully recyclable. The described process for scrap metal recycling and copper recovery was shown to be efficient and economically attractive. Additionally, the utility of employing the E(h) of the growth medium as a means for monitoring fluctuations in cell density in cultures of A. ferrooxidans is demonstrated.     

Phosphoinositide 3-Kinase p110�� Regulates Integrin ��IIb��3 Avidity and the Cellular Transmission of Contractile Forces

Phosphoinositide (PI) 3-kinase (PI3K) signaling processes play an important role in regulating the adhesive function of integrin α_IIbβ₃, necessary for platelet spreading and sustained platelet aggregation. PI3K inhibitors are effective at reducing platelet aggregation and thrombus formation in vivo and as a consequence are currently being evaluated as novel antithrombotic agents. PI3K regulation of integrin α_IIbβ₃ activation (affinity modulation) primarily occurs downstream of G_i-coupled and tyrosine kinase-linked receptors linked to the activation of Rap1b, AKT, and phospholipase C. In the present study, we demonstrate an important role for PI3Ks in regulating the avidity (strength of adhesion) of high affinity integrin α_IIbβ₃ bonds, necessary for the cellular transmission of contractile forces. Using knock-out mouse models and isoform-selective PI3K inhibitors, we demonstrate that the Type Ia p110β isoform plays a major role in regulating thrombin-stimulated fibrin clot retraction in vitro. Reduced clot retraction induced by PI3K inhibitors was not associated with defects in integrin α_IIbβ₃ activation, actin polymerization, or actomyosin contractility but was associated with a defect in integrin α_IIbβ₃ association with the contractile cytoskeleton. Analysis of integrin α_IIbβ₃ adhesion contacts using total internal reflection fluorescence microscopy revealed an important role for PI3Ks in regulating the stability of high affinity integrin α_IIbβ₃ bonds. These studies demonstrate an important role for PI3K p110β in regulating the avidity of high affinity integrin α_IIbβ₃ receptors, necessary for the cellular transmission of contractile forces. These findings may provide new insight into the potential antithrombotic properties of PI3K p110β inhibitors.     

The theropod furcula

The furcula is a structure formed by the midline fusion of the clavicles. This is the element which is unique to theropods and is important for understanding the link between birds and other theropods. New specimens from basal theropods suggest that the furcula appeared very early in theropod history. We review furcula development, function, and morphology, as well as the anatomical terminology applied to it. Furcular morphology is highly variable in crown‐group avians but is rather conserved among nonavian theropods. Here we review, or describe for the first time, the furculae in many nonavian theropods. Furculae occur in nearly all major clades of theropods, as shown by new theropod specimens from the Early Cretaceous of China and a close inspection of previously collected specimens. Informative phylogenetic characters pertaining to the furcula occur throughout Theropoda, though care should betake to consider taphonomic effects when describing furcular morphology. J. Morphol., 2009. © 2009 Wiley‐Liss, Inc.