We report the isolation of a cDNA encoding the third putative hyaluronan synthase, HAS3. Partial cDNAs and genomic fragments of mouse Has3 were obtained using a degenerate polymerase chain reaction approach. Partial clones facilitated the isolation of genomic and cDNA clones representing the mouse Has3 open reading frame. The open reading frame of 554 amino acids predicted a protein of 63.3 kDa with multiple transmembrane domains and several consensus HA binding motifs. Sequence comparisons indicated that mouse Has3 is most closely related to Has2 (71% amino acid identity) and also related to Has1 (57% identity), Xenopus laevis DG42 (56% identity), and Streptococcus pyogenes HasA (28% identity). Isolation of a genomic fragment of human HAS3 indicated high conservation between mouse and human sequences, similar to those observed for HAS1 and HAS2. Expression of the mouse Has3 open reading frame in transfected COS-1 cells led to high levels of hyaluronan synthesis, as determined through a classical particle exclusion assay, and by in vitro HA synthase assays. These results suggest that there are three putative mammalian hyaluronan synthases encoded by three separate but related genes which comprise a mammalian hyaluronan synthase (HAS) gene family. Hyaluronan (HA)1 is a linear unbranched glycosaminoglycan (GAG) composed of repeating disaccharide units of D-glucuronic acid(␤133)N-acetylglucosamine(␤134). HA is a major constituent of the extracellular matrix of most tissues and organs, especially during embryonic development, where it has been proposed to play important roles in cell migration, proliferation, and the development of tissue architecture (1-3). In addition, HA has been implicated in tumorigenesis, and defects in HA metabolism are a hallmark of several important diseases including rheumatoid arthritis, Grave's ophthalmopathy, cirrhosis of the liver, and accelerated aging in Werner's syndrome (1-4). Unlike other GAGs, which are synthesized within the Golgi network and attached to protein, HA is synthesized at the inner face of the plasma membrane and is subsequently extruded to the outside of the cell (5, 6). Recently, we and others (7-11) have identified two mammalian genes, HAS1 and HAS2, encoding putative plasma membrane HA synthases related to the Streptococcus pyogenes HA synthase, HasA. Expression of either HAS1 or HAS2 by cells led to high levels of HA biosynthesis, consistent with both proteins playing critical roles in HA biosynthesis, possibly as the HA synthases themselves.While attempting to isolate fragments of the human HAS2 gene using a degenerate PCR approach, we isolated fragments of an additional related gene in the mouse and human. We now report the molecular cloning and characterization of a cDNA encoding the third putative mammalian hyaluronan synthase, HAS3. EXPERIMENTAL PROCEDUREScDNA and Genomic Cloning and Expression-Previously described degenerate oligonucleotide primer pools (10), DEG 1 and DEG 5, were utilized in an attempt to amplify fragments of HAS genes from human and mous...

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A commutative residuated lattice (briefly, CRL) is an algebra A; ·, →, ∧, ∨, e such that A; ·, e is a commutative monoid, A; ∧, ∨ is a lattice, → is a binary operation, and for all a, b, c ∈ A,where ≤ is the lattice order. A unary operation ¬ on a CRL A is called an involution provided that for all a, b ∈ A, a → (¬b) = b → (¬a) and ¬¬a = a.In this case, the algebra A; ·, →, ∧, ∨, ¬, e is called an involutive CRL. We say a CRL (involutive or otherwise) is idempotent if it satisfies x · x ≈ x, linear if its lattice reduct is linearly ordered, and semilinear if it is a subdirect product of linear algebras. It is known that the class of all CRLs is an arithmetical variety, which has the congruence extension property (CEP). Every involutive CRL has the same congruences as its CRL-reduct, essentially because it satisfies ¬x ≈ x → (¬e).By a Sugihara monoid we mean an involutive CRL which is idempotent and whose lattice reduct is distributive. The class SM of Sugihara monoids is clearly a variety. As shown by Dunn in [1], every n-generated subdirectly irreducible member of SM is a residuated chain with at most 2n + 2 elements. Thus SM is locally finite and semilinear. SM is generated by a single algebra (which is based on the chain of non-zero integers). Because this algebra satisfies a quasi-equation not satisfied by SM, the quasivariety generated by this algebra is properly contained by SM.We call a variety V structurally complete if every proper subquasivariety of V generates a proper subvariety of V. Thus SM is not structurally complete. By a positive Sugihara monoid we mean any {¬}-free subreduct of a Sugihara monoid. PSM will denote the class of all positive Sugihara monoids, which happens to be a variety. Of course, PSM is locally finite because SM is. We are interested in whether PSM is structurally complete. The question for some related varieties is answered in [5]. The larger class of idempotent, semilinear CRLs is not structurally complete, although the class of its {e}-free subreducts is. In fact, this class of subreducts is primitive in the sense that each of its subquasivarieties is already a variety. The methods used in [5] do not apply to PSM, so we need a new approach to obtain the main result, that PSM is not only structurally complete, but primitive as well.We mention here that the properties under discussion have a significant interpretation in logic. A logical consequence relation is said to be structurally 1

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There is a growing need for quantitative traffic-estimating tools to improve pedestrian transportation safety, access, and mobility. A sketch-plan method is introduced to estimate peak-hour pedestrian trips for crossings at intersections (node) and parallel sidewalk-midblock (link) locations. This tool integrates pedestrian travel into routine trip-estimating by applying standard traffic data to quantify pedestrian trips. The method presented is based on access-egress mode trip generation and applies peak vehicle-per-hour turning movements, transit vehicle or passenger counts, and walk and bike counts or projections to produce total peak pedestrian-per-hour (pph) trips. A previous method used trip rates based on land use to generate pph trips. However, that model is 20 years old, requires detailed land use data, and does not distribute and assign pedestrian trips. The following sketch-plan method was developed in a case-study of a suburban growth corridor in Plattsburgh, New York. Sample applications of pedestrian trip-generation estimates are presented to illustrate how pedestrian travel-demand projections, in addition to vehicular traffic forecasting, can support the adoption of balanced facility treatments to meet the mobility and safety needs of all modes of transportation.