Usefulness of collagen plugging with VasoSeal after PTCA as compared to manual compression with identical sheath dwell times

This study investigated the usefulness of collagen plugging with VasoSeal (Datascope Corporation, Montvale, New Jersey) in patients after PTCA compared to a control group having identical sheath dwell times and therefore comparable levels of anticoagulation. A total of 150 patients were enrolled in this prospective and randomized study. Sheaths were pulled at exactly 5 hours after arterial puncture. Time to hemostasis and local complications were determined. There were no statistical differences in baseline characteristics. The mean time to hemostasis in the collagen group was significantly shorter (3 +/- 3 minutes) than that of the control group (17.4 +/- 7 minutes). At 24 hours, 23% of the collagen group patients had a small, 1% a medium and 4% a large hematoma. In the control group, 32% had a small and 4% a medium-sized hematoma, but no patient a large hematoma. After collagen, one patient developed a pseudoaneurysm needing vascular surgery. In the control group, no major complications occurred. Compared to patients with manual compression at an identical sheath dwell time and an identical level of anticoagulation, there was a significant reduction in time to hemostasis but no statistical difference regarding local complications. Although the incidence of medium or large hematoma was low, the trend towards a decreased risk of smaller hematomas seemed to be counterbalanced by an increased risk of larger hematomas.

Usefulness of collagen plugging with VasoSeal after PTCA as compared to manual compression with identical sheath dwell times

This study investigated the usefulness of collagen plugging with VasoSeal in patients after PTCA compared to a control group having identical sheath dwell times and therefore comparable levels of anticoagulation. A total of 150 patients were enrolled in this prospective and randomized study. Sheaths were pulled at exactly 5 h after arterial puncture. Time to hemostasis and local complications were determined. There were no statistical differences in baseline characteristics. The mean time to hemostasis in the collagen group was significantly shorter (3 +/- 3 min) than that of the control group (17.4 +/- 7 min). At 24 h, 23% of the collagen group patients had a small, 1% a medium and 4% a large hematoma. In the control group, 32% had a small, 4% a medium sized, but no patient a large hematoma. After collagen, one patient developed a pseudoaneurysm needing vascular surgery. In the control group, no major complication occurred. Compared to patients with manual compression at an identical sheath dwell time and an identical level of anticoagulation, there was a significant reduction in time to hemostasis but no statistical difference regarding local complications. Although the incidence of medium or large hematoma was low, the trend towards a decreased risk of smaller hematomas seemed to be counterbalanced by an increased risk of larger hematomas.

C-terminal structure and mobility of rabbit skeletal muscle light meromyosin as studied by one- and two-dimensional 1H NMR spectroscopy and X-ray small-angle scattering

Intact rabbit myosin and two different C-terminal fragments of rabbit muscle light meromyosin (LMM) expressed in Escherichia coli, LMM-30, and LMM-30C', were studied by 1H NMR spectroscopy. X-ray small-angle scattering shows that at high ionic strength two polypeptide chains of LMM-30 (which consists of the C-terminal 262 amino acids of myosin heavy chain) or LMM-30C' (which corresponds to LMM-30 but lacks the last 17 residues) assemble to form an alpha-helical coiled-coil as it is found also in myosin. The last 12 C-terminal residues of one polypeptide chain of LMM-30 and the last 9 C-terminal residues of the other chain are very mobile. The last 8 residues of the two strands are equivalent from the NMR point of view and unfolded; the valine residues in position 255 in the two strands are not equivalent, suggesting an interaction between the two strands, Ser-252, Arg-253, and Asp-254 are completely immobilized in one of the polypeptide strands and partly mobile in the other. Essentially the same pattern is observed in intact myosin. In spite of the large molecular weights of LMM-30 and LMM-30C', it is possible to resolve almost all aromatic residues and to determine the pK values of all the 4 tyrosine and of 9 (out of 10) histidine residues. The tyrosine residues in the two strands are equivalent in the two polypeptide chains and both have a pK of 10.5. The pK values of the histidine residues vary between 5.7 and 7.0.

Rabbit skeletal muscle myosin. Unfolded carboxyl-terminus and its role in molecular assembly

We have expressed in E. coli segments of the rod portion of rabbit skeletal fast muscle myosin and compared physical properties of two different species, LMM-30 and LMM-30C'. LMM-30 consists of 263 amino acids including the original C-terminus of myosin heavy chain. LMM-30C' is colinear with LMM-30, but is devoid of 17 residues at the C-terminus. 1H NMR spectroscopy indicates that the C-terminus of LMM-30, but not of LMM-30C' is unfolded and freely mobile. Furthermore, the present results show that the unfolded C-terminus is essential for molecular assembly of LMM-30; at pH 8.0 LMM-30, but not LMM-30C', formed aggregates upon decreasing the ionic strength.

A simple procedure to produce monospecific polyclonal antibodies of high affinity against actin from muscular sources

A simple and effective technique to produce monospecific polyclonal antibodies of high affinity against actin is described. In this procedure, rabbit skeletal muscle actin in the 1:1 complex with bovine pancreatic deoxyribonuclease I is used as antigen to immunize rabbits. The antisera obtained are shown to contain antibodies against both actin and deoxyribonuclease I. By affinity chromatography the two antibody preparations were separated and characterized. The affinity-purified anti-deoxyribonuclease I and anti-actin do not show cross-reactivity. Thus, anti-deoxyribonuclease I inhibits the enzymic activity of deoxyribonuclease I and stains the enzyme after Western blotting. Affinity-purified anti-actin does not inhibit deoxyribonuclease I activity and stains only actin after Western blotting. The affinity-purified anti-actin can be used in a number of different actin-detecting techniques such as in immunohistochemistry and in immunoblotting techniques. This antibody recognizes only actins from muscular tissues with high affinity. Immunoblots of polyacrylamide gels in the presence of ampholytes (IEF) indicate that this antibody only recognizes the alpha-variants of actin. Thus, the skeletal and cardiac alpha-actins are recognized but not the smooth muscle gamma-isoform and the cytoplasmic actins. Vascular smooth muscle alpha-actin is not recognized when using immunoblotting or enzyme-linked immunosorbent techniques. On frozen sections, however, the anti-actin antibody clearly stained vascular smooth muscle cells. Epitope analysis using actin fragments generated by limited proteolysis and selective cleavage using hydroxylamine indicate that this antibody is directed against a rather limited region within the N-terminus of actin.