Immunolocalization of β-1-4-galactan and its relationship with lignin distribution in developing compression wood of Cryptomeria japonica

Compression wood (CW) contains higher quantities of β-1-4-galactan than does normal wood (NW). However, the physiological roles and ultrastructural distribution of β-1-4-galactan during CW formation are still not well understood. The present work investigated deposition of β-1-4-galactan in differentiating tracheids of Cryptomeria japonica during CW formation using an immunological probe (LM5) combined with immunomicroscopy. Our immunolabeling studies clearly showed that differences in the distribution of β-1-4-galactan between NW (and opposite wood, OW) and CW are initiated during the formation of the S₁ layer. At this stage, CW was strongly labeled in the S₁ layer, whereas no label was observed in the S₁ layer of NW and OW. Immunogold labeling showed that β-1-4-galactan in the S₁ layer of CW tracheids significantly decreased during the formation of the S₂ layer. Most β-1-4-galactan labeling was present in the outer S₂ region in mature CW tracheids, and was absent in the inner S₂ layer that contained helical cavities in the cell wall. In addition, delignified CW tracheids showed significantly more labeling of β-1-4-galactan in the secondary cell wall, suggesting that lignin is likely to mask β-1-4-galactan epitopes. The study clearly showed that β-1-4-galactan in CW was mainly deposited in the outer portion of the secondary cell wall, indicating that its distribution may be spatially consistent with lignin distribution in CW tracheids of Cryptomeria japonica.     

Plato and Peirce on Likeness and Semblance

In his well-known essay, ??What Is a Sign???(CP 2.281, 285) Peirce uses ??likeness?? and ??resemblance?? interchangeably in his definition of icon. The synonymity of the two words has rarely, if ever, been questioned. Curiously, a locus classicus of the pair, at least in F. M. Cornford??s English translation, can be found in a late dialogue of Plato, namely, the Sophist. In this dialogue on the myth and truth of the sophists?? profession, the mysterious ??stranger??, who is most likely Socrates?? persona, makes the famous distinction between eikon (likeness) and phantasma (semblance) (236a,b). For all his broad knowledge in ancient philosophy, Peirce never mentioned this parallel; nor has any Peircean scholar identified it. There seems to be little problem with eikon as likeness, but phantasma may give rise to a puzzle which this paper will attempt to solve. Plato uses two pairs of words: what eikon is to phantasma is eikastikén (the making of likeness [235d]) to phantastikén (semblance making [236c]). In other words, icons come into being because of the act of icon-making, which is none other than indexicality. Witness what Peirce says about the relationship between photographs and the objects they represent: ??But this resemblance is due to the photographs having been produced under such circumstances that they were physically forced to correspond point by point to nature.?? (Ibid.) Thus the iconicity which links the representamen (sign) and its object is made possible not only by an interpretant, but also by idexisation. Their possible etymological and epistemological links aside, the Peircean example of photographing and the Platonic discussion of painting and sculpturing in the Sophist, clearly show the physio-pragmatic aspect of iconicity. The paper will therefore reread the Peircean iconicity by closely analysing this relatively obscure Platonic text, and by so doing restore to the text its hidden semiotic dimension.     

Anti-Inflammatory Effects of Acupuncture Stimulation via the Vagus Nerve

Although acupuncture therapy is widely used in traditional Asian medicine for the treatment of diverse internal organ disorders, its underlying biological mechanisms are largely unknown. Here, we investigated the functional involvement of acupuncture stimulation (AS) in the regulation of inflammatory responses. TNF-α production in mouse serum, which was induced by lipopolysaccharide (LPS) administration, was decreased by manual acupuncture (MAC) at the zusanli acupoint (stomach36, ST36). In the spleen, TNF-α mRNA and protein levels were also downregulated by MAC and were recovered by using a splenic neurectomy and a vagotomy. c-Fos, which was induced in the nucleus tractus solitarius (NTS) and dorsal motor nucleus of the vagus nerve (DMV) by LPS and electroacupuncture (EAC), was further increased by focal administration of the AMPA receptor blocker CNQX and the purinergic receptor antagonist PPADS. TNF-α levels in the spleen were decreased by CNQX and PPADS treatments, implying the involvement of inhibitory neuronal activity in the DVC. In unanesthetized animals, both MAC and EAC generated c-Fos induction in the DVC neurons. However, MAC, but not EAC, was effective in decreasing splenic TNF-α production. These results suggest that the therapeutic effects of acupuncture may be mediated through vagal modulation of inflammatory responses in internal organs.     

Effect of Composition and Impurities on the Phosphorescence of Green-Emitting Alkaline Earth Aluminate Phosphor

Recent improvements to SrAl₂O₄:Eu²⁺, Dy³⁺ phosphors have enabled the use of luminescent hosts with a stable crystal structure and high physical and chemical stability, thus overcoming the bottleneck in the applicability of ZnS:Cu phosphors. However, enhancement of afterglow lifetime and brightness in SrAl₂O₄:Eu²⁺, Dy³⁺ phosphors remains a challenging task. Here, we have improved the afterglow characteristics in terms of persistence time and brightness by a systematic investigation of the composition of Eu-doped alkaline earth aluminate SrAl₂O₄:Eu²⁺, Dy³⁺ crystals. We found that a Dy³⁺/Eu²⁺ ratio of ~2.4 and ~0.935 mol Eu²⁺ (per mol of SrAl₂O₄) gave the brightest and longest emissions (11% and 9% increase for each). Doping with Si⁴⁺ also resulted in a slight increase in brightness up to ~15%. Doping with alkali metal or alkaline earth metal significantly enhanced the phosphorescence intensity. In particular, doping with 0.005 mol Li⁺ (per mol of SrAl₂O₄) alone boosted the phosphorescence intensity to 239% of the initial value, as compared to that observed for the non-doped crystal, while doping with 0.01 mol Mg²⁺ and 0.005 mol Li⁺ (per 1 mol SrAl₂O₄) boosted the phosphorescence intensity up to 313% of the initial value. The results of this investigation are expected to act as a guideline for the synthesis of bright and long persistent phosphors, and facilitate the development of persistent phosphors with afterglow characteristics superior to those of conventional phosphors.     

Secretion of Recombinant Pediocin PA-1 by Bifidobacterium longum, Using the Signal Sequence for Bifidobacterial α-Amylase

A recombinant DNA, encoding the chimeric protein of the signal sequence for bifidobacterial α-amylase mature pediocin PA-1, was introduced into Bifidobacterium longum MG1. Biologically active pediocin PA-1 was successfully secreted from the strain and showed bactericidal activity against Listeria monocytogenes and the same molecular mass as native pediocin PA-1.