Hepatocyte growth factor (HGF) activator is a serine protease that is produced and secreted by the liver and circulates in the blood as an inactive zymogen. In response to tissue injury, the HGF activator zymogen is converted to the active form by limited proteolysis. The activated HGF activator converts an inactive single chain precursor of HGF to a biologically active heterodimer in injured tissue. The activated HGF may be involved in the regeneration of the injured tissue. In this study, we purified an inhibitor of HGF activator from the conditioned medium of a human MKN45 stomach carcinoma cell line and molecularly cloned its cDNA. The sequence of the cDNA revealed that the inhibitor has two well defined Kunitz domains, suggesting that the inhibitor is a member of the Kunitz family of serine protease inhibitors. The sequence also showed that the primary translation product of the inhibitor has a hydrophobic sequence at the COOH-terminal region. Inhibitory activity toward HGF activator was detected in the membrane fraction as well as in the conditioned medium of MKN45 cells. These results suggest that the inhibitor may be produced as a membrane-associated form and secreted by the producing cells as a proteolytically truncated form.

Potato D-enzyme was purified from recombinant Escherichia coli, and its action on synthetic amylose (average M r of 320,000) was analyzed. D-enzyme treatment resulted in a decrease in the ability of the amylose to form a blue complex with iodine. Analysis of the products indicated that the enzyme catalyzes an intramolecular transglycosylation reaction on amylose to produce cyclic ␣-1,4-glucan (cycloamylose). Confirmation of the cyclic structure was achieved by demonstrating the absence of reducing and nonreducing ends, resistance to hydrolysis by glucoamylase (an exoamylase), and by "time of flight" mass spectrometry. The degree of polymerization of cycloamylose products was determined by time of flight mass spectrometry analysis and by highperformance anion-exchange chromatography following partial acid hydrolysis of purified cycloamylose molecules and was found to range from 17 to several hundred. The yield of cycloamylose increased with time and reached >95%. D-enzyme did not act upon purified cycloamylose, but if glucose was added as an acceptor molecule, smaller cyclic and linear molecules were produced. The mechanism of the cyclization reaction, the possible role of the enzyme in starch metabolism, and the potential applications for cycloamylose are discussed.

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We develop the frame-like formulation of massive bosonic higher spins fields in the case of 3-dimensional (A)dS space with the arbitrary cosmological constant. The formulation is based on gauge-invariant description by involving the Stueckelberg auxiliary fields. The explicit form of the Lagrangians and the gauge transformation laws are found. The theory can be written in terms of gauge-invariant objects similar to the massless theories, thus allowing us to hope to use the same methods for investigation of interactions. In the massive spin 3 field example we are able to rewrite the Lagrangian using the new the socalled separated variables, so that the study of Lagrangian formulation reduces to finding the Lagrangian containing only half of the fields. The same construction takes places for arbitrary integer spin field as well. Further working in terms of separated variables, we build Lagrangian for arbitrary integer spin and write it in terms of gauge-invariant objects. Also, we demonstrate how to restore the full set of variables, thus receiving Lagrangian for the massive fields of arbitrary spin in the terms of initial fields.

We study one-loop renormalization in the most general metric-dilaton theory with second derivative terms only. The classical action includes three arbitrary functions of the dilaton. The general theory can be divided into two classes: models of one are equivalent to gravity conformally coupled to a scalar field and also to general relativity with a cosmological term. The models of the second class have one extra degree of freedom which corresponds to the dilaton. We calculate the one-loop divergences for the models of the second class and find that the theory is not renormalizable off the mass shell. At the same time the arbitrary functions of the dilaton in the starting action can be fine-tuned in such a way that all the higher derivative counterterms disappear on shell. The only structures in both the classical action and counterterms, which survive on shell, are the potential (cosmological) ones. They can be removed by renormalization of the dilaton field that acquires the nontrivial anomalous dimension, which leads to the effective running of the cosmological constant. Another application of our calculations is the following. For some special choice of the arbitrary functions our dilaton model is equivalent to general relativity with an additional R2 term. Such an equivalence holds at the quantum level if we do not introduce the external source for the dilaton field. Thus our calculations in a general dilaton model in original variables include quantum A +aR+flR2 theory as the particular case. PACS number(s): 04.60.-m, 04.50.+h, 98.80.H~