Extensive host range of an endophytic fungus, <Emphasis Type="Italic">Guignardia endophyllicola</Emphasis> (anamorph: <Emphasis Type="Italic">Phyllosticta capitalensis</Emphasis>)

Isolation of endophytic species of Guignardia (anamorph: Phyllosticta) from healthy leaves of 94 plants (91 species and 3 varieties) in 69 genera, 42 families, was carried out in a test site (Kyoto Herbal Garden) to investigate the host range of Guignardia endophyllicola (anamorph: Phyllosticta capitalensis). Species of Guignardia and Phyllosticta were isolated from the leaves of 67 plants (66 species and 1 variety) belonging to 54 genera, 38 families. Among them, 53 isolates from different plants belonging to 43 genera in 36 families were similar in morphology, and sequence analysis of internal transcribed spacer (ITS) regions of ribosome DNA revealed these isolates to be conspecific with G. endophyllicola. In addition, this fungus was isolated from leaves of various plants collected in different places in Japan and Thailand. Thus, this endophytic fungus has been revealed to live within various vascular plants, angiosperms, gymnosperms, and pteridophytes.     

Establishment of monokaryotic and dikaryotic isolates of Hedgehog mushrooms (Hydnum repandum and related species) from basidiospores

Hydnum repandum and its relatives are gourmet edible ectomycorrhizal mushrooms. However, no reliable pure cultures have been reported in this genus. Here, we report for the first time the successful isolation of mycelial strains from basidiospores in the genus Hydnum. Basidiospores obtained from basidioma samples were aseptically inoculated onto modified Norkran's C (MNC) medium, MNC containing n-butyric acid (n-MNC), or MNC with gellan gum instead of agar (G-MNC). Although basidiospore germination was observed in most samples, the isolation rate was higher from MNC (91.7%) and G-MNC (93.8%) than from n-MNC (36.4%). Most established isolates were monokaryotic and lacked a clamp connection, but three were dikaryotic and had clamp connections. Established isolates were identified by molecular phylogenetic analysis of the internal transcribed spacer region of the rRNA gene. These results suggest that basidiospores can be used to establish monokaryotic and dikaryotic isolates of Hydnum species.     

Viral FLIP enhances Wnt signaling downstream of stabilized beta-catenin, leading to control of cell growth

Death receptor-mediated apoptosis is potently inhibited by viral FLIP (FLICE/caspase 8 inhibitory protein), which is composed of two tandemly repeated death effector domains (DEDs), through reduced activation of procaspase 8. Here, we show that equine herpesvirus 2-encoded viral FLIP E8 enhances Wnt/beta-catenin signaling in a variety of cell lines. E8 was shown to strikingly augment Wnt3a signaling, as shown both in a luciferase assay for T-cell factor/beta-catenin and through induction of endogenous cyclin D1. The effect of E8 was independent of its direct binding activity with DED-containing signaling molecules, including caspase 8 and FADD, in death receptor-mediated apoptosis. E8 enhanced Wnt signaling downstream of stabilized beta-catenin, while a long form of cellular FLIP (c-FLIP(L)) enhanced stabilization of beta-catenin in 293T cells. Consequently, coexpression of E8 and c-FLIP(L) synergistically increased Wnt signaling in 293T cells. Moreover, E8-mediated stimulation of Wnt signaling induced dramatic growth retardation in untransformed cell lines but not in transformed cell lines. Thus, viral FLIP E8 not only inhibits death receptor-mediated apoptosis but also enhances Wnt signaling pathways that are closely related to those of both ontogenesis and oncogenesis.     

Recognition and characterization of four Thai xylariaceous fungi inhabiting various tropical foliages as endophytes by DNA sequences and host plant preference

A total of 202 strains of xylariaceous fungi (183 endophytic strains isolated from 25 plant species of 24 genera in 21 families and 19 saprobic strains), segregated into four clades, were examined by nuclear rDNA internal transcribed spacer (ITS) sequence and beta-tubulin coding region analyses to clarify their taxonomic status and species boundaries. Three of the four species clades were assigned to Xylaria cubensis (100 strains), Xylaria grammica (33 strains), and Nemania diffusa (48 strains). Another fungus was tentatively assigned to Nemania cf. bipapillata (21 strains). Comparison of the host plants revealed that X. cubensis inhabited healthy leaves of at least 24 plant species (23 genera of 21 families) as endophytes; N. diffusa was found on 19 plant species (18 genera of 15 families), Nemania cf. bipapillata on 11 species (10 genera of 9 families), and X. grammica on 8 species (8 genera of 7 families). The present results suggest that the major xylariaceous endophytes in tropical plants are likely to be non-host specific, or have a wide range of host plant preferences.     

Trichoderma matsushimae and T. aeroaquaticum: two aero-aquatic species with Pseudaegerita-like propagules

Four isolates tentatively identified as Pseudaegerita matsushimae on the basis of the morphology of bulbil-like propagules were collected from substrates submerged in water in Thailand and Japan. In culture studies the two Thai isolates were found to produce phialoconidia on conidiogenous cells and phialoconidiophores whose morphology was similar to that of Trichoderma. Phylogenetic analysis based on D1/D2 regions of LSU rDNA sequences showed that the four isolates were nested in Hypocrea/Trichoderma (Hypocreales) while P. corticalis, the type species of Pseudaegerita, belongs to Hyaloscypha (Helotiales). Preliminary analysis by ISTH Web tools based on 5.8S-ITS rDNA and phylogenetic analysis based on rpb2 and tef1-int4 genes showed that the isolates have specific sequences of Trichoderma (anchors 1-5) and belong to the Hamatum clade but they grouped apart from any known species of Trichoderma. The sequences of the tef1-int4 gene, which were amplified from the authentic specimen of P. matsushimae (IMI 266915), also showed that it belongs to the Hamatum clade closely clustering with T. yunnanense but separate from our four isolates. The morphology of P. matsushimae (IMI 266915), especially the sizes of phialides and phialoconidia, were different from T. yunnanense. Thus, we conclude that IMI 266915 and our isolates are to be assigned to two different species in the Hamatum clade of Trichoderma, although both species have similar morphology of bulbils and phialoconidia. Morphology and molecular data revealed that P. matsushimae should be assigned to the genus Trichoderma as T. matsushimae and the Thai and Japanese isolates are placed in T. aeroaquaticum sp. nov. This finding supports the interpretation that aero-aquatic fungi have evolved from terrestrial fungi. We assume that these fungi probably were derived from typically soil-inhabiting species of Trichoderma; an adaptation to aquatic environments is shown by formation of bulbil-like propagules floating on water.     

Occupational health hazards resulting from elevated work rate situations.

Some occupational health hazards resulting from an elevated rate of work due to recent mechanization and automatization are discussed on the basis of results of health examinations. A rapid increase of a cervicobrachial disorder among young cash register and packing machine operators has been observed. Switching to the use of electronic cash registers has been shown to have only limited efficacy due to increased operation speed, and high-speed complex finger and hand movements of packer operators have also proven to be as hazardous as key-board operations. The high incidence of low-back pain, in particular gradually developing pain, among workers in electric power supply work has been suggested to be the result of quick and intensified work to meet increasing supply demand. Likewise, the workload of electric locomotive and bullet train drivers has increased in accordance with increased train speeds, and has been shown to have had significant effects on their health particularly in regards to neural strain, intra-cab environment such as air pressure change, vibration, and noise, and rotation on irregular shifts. New steps seem required therefore to meet the new health problems arising from a combination of modern technological changes and elevated working speeds.     

Evolution of gamete size in primitive taxa without mating types

An ESS model to better understand the evolutionary dynamics of a primitive non-mating type gamete size was developed with reference to the PBS (Parker, Baker and Smith’s) theory, which was based on total numbers of zygotes formed and the zygote survival rates. We did not include mating types since it has been suggested that primitive mating systems did not have mating types. As input parameters, we used experimental data on gamete motility of marine green algae. Based on hard sphere collision mechanics, we detailed the fertilization kinetics of gametes that swim in water prior to fusing with their partners through a set of coupled, non-linear differential equations. These equations were integrated numerically using typical values of the constant parameters. To estimate the relative zygote survival rate, we used a function that is sigmoid in shape and examined some evolutionarily stable strategies in mating systems that depend on optimizing values of the invasion success ratio.     

Trichoderma mienum sp. nov., isolated from mushroom farms in Japan

During an investigation of Hypocrea/Trichoderma species inhabiting mushroom bedlogs, we found five strains of an undescribed species from a culture collection. These were analyzed using a combined approach, including morphology of holomorph, cultural studies, and phylogenetic analyses of the rRNA gene cluster of the internal transcribed spacer region, translation elongation factor 1-α, and RNA polymerase subunit II gene sequences. Distinctive morphological characters include stromata with green ascospores produced on potato dextrose agar medium, and Gliocladium-like to irregularly Verticillium-like conidiophores. In phylogenetic analyses, this species belongs to the Semiorbis clade, but its morphological characteristics do not match the other members of this clade. Based on morphological observations and phylogenetic analyses, we describe this as a new species, Trichoderma mienum, representing its Hypocrea teleomorph and Trichoderma anamorph.     

IL-6 Amplifier, NF-κB-Triggered Positive Feedback for IL-6 Signaling, in Grafts Is Involved in Allogeneic Rejection Responses

The IL-6-amplifier first was discovered as a synergistic activation mechanism for NF-κB/STAT3 in type 1 collagen(+) cells. This process is marked by the hyperinduction of chemokines and subsequent local inflammation that leads to autoimmune diseases. In this study, we show that IL-6 amplifier activation in grafts plays important roles in allogeneic graft rejection by using a tracheal heterotopic transplantation model that includes bronchiolitis obliterans, a pathological marker for chronic rejection. IL-6, epidermal growth factor, and IFN-γ all stimulate IL-6 amplifier activation, whereas CCL2, a chemotactic factor for Th1 cells, was one of the amplifier's main targets. Interestingly, IFN-γ hyperinduced CCL2 in type 1 collagen(+) cells via the IL-6 amplifier at least in vitro. In addition, we detected IL-6, CCL2, phospho-STAT3, and phospho-NF-κB in epithelial type 1 collagen(+) cells of allogeneic tracheal grafts. These results show that IL-6 amplifier activation in grafts plays a critical role for graft rejection responses after allogeneic transplantation, including chronic rejection. From these results, we consider whether the IL-6 amplifier in grafts might be a valuable therapeutic target for the prevention of transplant rejection, including chronic rejection.     

Designing potent derivatives of ovokinin(2-7), an anti-hypertensive peptide derived from ovalbumin

We obtained a potent anti-hypertensive peptide, RPFHPF, by replacing the amino acid residues of ovokinin(2-7) (RADHPF), an orally active anti-hypertensive peptide derived from ovalbumin. After intravenous administration in anesthetized Wistar rats, the designed peptide [Pro2, Phe3]-ovokinin(2-7) had a long-lasting hypotensive activity at a dose of 10 mg/kg, while that of ovokinin(2-7) was only transient even at a dose of 100 mg/kg. After oral administration in conscious spontaneously hypertensive rats (SHRs), [Pro2, Phe3]-ovokinin(2-7) significantly lowered the systolic blood pressure in a dose-dependent manner. It is noteworthy that the minimum effective dose of [Pro2, Phe3]-ovokinin(2-7) was 0.3 mg/kg, about one-thirtieth of that of ovokinin(2-7). On the other hand, orally administered [Pro2, Phe3]-ovokinin(2-7) did not show any significant hypotensive effect in normotensive Wistar-Kyoto rats (WKYs) even at a dose of 3 mg/kg. Taken together, [Pro2, Phe3]-ovokinin(2-7) proved to be an ideal, potent anti-hypertensive peptide with little effect on normal blood pressure when given orally.