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Numerically controlled local wet etching (NC-LWE) is a novel figuring method for fabricating the ultraprecision optics or finishing the functional materials. In this method, the localized etching area is formed by applying the combination nozzle that is constructed from the supply part and the suction part of the etchant, and the removal volume anywhere on the workpiece surface is determined by the dwelling time of the nozzle. We applied the NC-LWE for fabricating the piano-elliptical mirror made of synthesized quartz glass to focus the hard X-ray beam, and achieved a figure error of 27 nm (p-v) by applying a 1-dimensional numerically controlled figuring utilizing a square-shaped nozzle.

The acrosome reaction of newt sperm is induced at the surface of egg jelly and the acrosome-reacted sperm acquire the ability to bind to the vitelline envelope. However, because the substance that induces the acrosome reaction has not been identified, the mechanism by which the acrosome-reacted sperm bind to the vitelline envelope remains unclear. We found here that a Dolichos biforus agglutinin (DBA) specifically mimicked the acrosome reaction immediately upon its addition in the presence of milimolar level Ca2+. Fluorescein isothiocyanate-labeled DBA bound specifically to the acrosomal cap of the intact sperm in the presence of a Ca2+-chelating agent, EDTA, suggesting that binding of DBA to the native receptor for the egg jelly substance on the acrosomal region took the place of the egg jelly substance-induced acrosome reaction. In contrast, the sperm that had been acrosome reacted by DBA treatment did not bind to the vitelline envelope of the egg whose jelly layers were removed. Subsequent addition of jelly extract caused the sperm binding to vitelline envelope, indicating that the egg jelly of the newt contains substances that are involved in not only inducing the acrosome reaction but also binding to the vitelline envelope. This is the first demonstration of the involvement of egg jelly substance in the binding of acrosome-reacted sperm to the vitelline envelope. J. Exp. Zool. 307A:301–311, 2007. © 2007 Wiley-Liss, Inc.

Estrogen deficiency causes bone loss as a result of accelerated osteoclastic bone resorption. It also has been reported that estrogen deficiency is associated with an increase in the number of pre-B cells in mouse bone marrow. The present study was undertaken to clarify the role of altered B lymphopoiesis and of the receptor activator of nuclear factor-kappa B ligand (RANKL), a key molecule in osteoclastogenesis, in the bone loss associated with estrogen deficiency. In the presence of prostaglandin E2 (PGE2), the activity to form tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like cells was significantly greater in bone marrow cells derived from ovariectomized (OVX) mice than in those from sham-operated mice. Northern blot analysis revealed that PGE2 increased the amount of RANKL messenger RNA (mRNA) in bone marrow cells, not only adherent stromal cells but nonadherent hematopoietic cells; among the latter, RANKL mRNA was more abundant in OVX mice than in shamoperated mice and was localized predominantly in B220+ cells. Flow cytometry revealed that most B220+ cells in bone marrow were RANKL positive and that the percentage of RANKL-positive, B220low cells was higher in bone marrow from OVX mice than in that from sham-operated mice. The increase in the expression of RANKL and the percentage of these cells in OVX mice was abolished by the administration of indomethacin in vivo. PGE2 also markedly increased both the level of RANKL mRNA and cell surface expression of RANKL protein in the mouse pre-B cell line 70Z/3. Finally, osteoclastogenic response to PGE2 was reduced markedly by prior depletion of B220+ cells, and it was restored by adding back B220+ cells. Taken together with stimulated cyclo-oxygenase (COX)-2 activity by tumor necrosis factor alpha (TNF-alpha) and interleukin-1 (IL-1) in estrogen deficiency, these results suggest that an increase in the number of B220+ cells in bone marrow may play an important role in accelerated bone resorption in estrogen deficiency because B220+ cells exhibit RANKL on the cell surface in the presence of PGE2, thereby leading to accelerated osteoclastogenesis.

Outer arm dynein was purified from sperm flagella of a sea anemone, Anthopleura midori, and its biochemical and biophysical properties were characterized. The dynein, obtained at a 20S ATPase peak by sucrose density gradient centrifugation, consisted of two heavy chains, three intermediate chains, and seven light chains. The specific ATPase activity of dynein was 1.3 micromol Pi/mg/min. Four polypeptides (296, 296, 225, and 206 kDa) were formed by UV cleavage at 365 nm of dynein in the presence of vanadate and ATP. In addition, negatively stained images of dynein molecules and the hook-shaped image of the outer arm of the flagella indicated that sea anemone outer arm dynein is two-headed. In contrast to protist dyneins, which are three-headed, outer arm dyneins of flagella and cilia in multicellular animals are two-headed molecules corresponding to the two heavy chains. Phylogenetic considerations were made concerning the diversity of outer arm dyneins.