Exacerbation of experimental allergic asthma by augmented Th2 responses in WSX-1-deficient mice

WSX-1 (IL-27R) is a class I cytokine receptor with homology to gp130 and IL-12 receptors and is typically expressed on CD4+ T lymphocytes. Although previous reports have clarified that IL-27/WSX-1 signaling plays critical roles in both Th1 differentiation and attenuation of cell activation and proinflammatory cytokine production during some bacterial or protozoan infections, little is known about the importance of WSX-1 in cytokine-mediated diseases of allergic origin. To this aim, we took advantage of WSX-1-deficient (WSX-1(-/-)) mice and induced experimental asthma, in which Th2 cytokines are central modulators of the pathology. OVA-challenged WSX-1(-/-) mice showed marked enhancement of airway responsiveness with goblet cell hyperplasia, pulmonary eosinophil infiltration, and increased serum IgE levels compared with wild-type mice. Production of Th2 cytokines, which are largely responsible for the pathogenesis of asthma, was augmented in the lung or in the culture supernatants of peribronchial lymph node CD4+ T cells from WSX-1(-/-) mice compared with those from wild-type mice. Surprisingly, IFN-gamma production was also enhanced in WSX-1(-/-) mice, albeit at a low concentration. The cytokine overproduction, thus, seems independent from the Th1-promoting property of WSX-1. These results demonstrated that IL-27/WSX-1 also plays an important role in the down-regulation of airway hyper-reactivity and lung inflammation during the development of allergic asthma through its suppressive effect on cytokine production.     

A genetic analysis of the Sakishima islanders reveals no relationship with Taiwan aborigines but shared ancestry with Ainu and main‐island Japanese

The Sakishima islands are members of the Ryukyu island chain, stretching from the southwestern tip of the Japanese archipelago to Taiwan in the East China Sea. Archaeological data indicate cultural similarities between inhabitants of prehistoric Sakishima and Neolithic Taiwan. Recent studies based on tooth crown traits show remarkably high inter‐island diversity among Ryukyu islanders, suggesting that the Sakishima islanders might have genetic backgrounds distinct from main‐island Okinawa people. To investigate the genetic diversity of the Ryukyu islanders, we analyzed mtDNA, Y chromosome, and autosomal short tandem repeat loci in a sample of main‐island Okinawa people and Sakishima (Miyako and Ishigaki) islanders whose participated in a previous study of tooth crown morphology. Our phylogenetic analysis of maternal (mtDNA) and paternal (Y chromosome) lineages shows that the Sakishima islanders are more closely related to people from the Japanese archipelago than to Taiwan aborigines. Miyako islanders and the Hokkaido Ainu have the first and second highest frequencies (respectively) of the Y‐chromosomal Alu‐insertion polymorphism, which is a presumable Jomon marker. Genetic diversity statistics show no evidence of demographic reduction or of extreme isolation in each island's population. Thus, we conclude that 1) Neolithic expansion from Taiwan did not contribute to the gene pool of modern Sakishima islanders, 2) male‐lineage of the Ryukyu islanders likely shares a common ancestor with the Hokkaido Ainu who are presumably direct descendants of the Jomon people, and 3) frequent reciprocal gene flow among islands has masked the trace of common ancestry in the Ryukyu island chain. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc.     

Purification and characterization of aspartic protease derived from Sf9 insect cells

An aspartic protease that is significantly produced by baculovirus-infected Spodoptera frugiperda Sf9 insect cells was purified to homogeneity from a growth medium. To monitor aspartic protease activity, an internally quenched fluoresce (IQF) substrate specific to cathepsin D was used. The purified aspartic protease showed a single protein band on SDS-PAGE with an apparent molecular mass of 40 kDa. The N-terminal amino acid sequence of the enzyme had a high homology to a Bombyx mori aspartic protease. The enzyme showed greatest affinity for the IQF substrate at pH 3.0 with a K(m) of 0.85 μM. The k(cat) and k(cat)/K(m) values were 13 s(-1) and 15 s(-1) μM(-1) respectively. Pepstatin A proved to be a potent competitive inhibitor with inhibitor constant, K(i), of 25 pM.     

Relationship between plant cover type and soil properties on Syunkunitai coastal sand dune in eastern Hokkaido

A survey of soils and trees was conducted on Syunkunitai coastal sand dune in eastern Hokkaido to clarify the relationships between the soil properties and the plant cover type. A belt transect of 360m in length was established across the dune. Three community types, that is, a Picea glehnii forest, an Abies sachalinensis forest, and a salt marsh were recognized. Soil types at the study area were determined to be sandy immature soil and peat soil. Their horizon sequences were described as A₀–V–C or T–V–C layers (A₀, T, V, and C indicate layers of leaf litter, peat, volcanic deposit, and parent material, respectively). The Abies sachalinensis forest was characterized by a relatively high calcium concentration in the surface soil layer and a tendency for podzolization in the volcanic deposit layer. The Picea glehnii forest was characterized by peat accumulation because of the high ground water table, volcanic deposits in the soil profile, and the strong influence of sea salt on the soil chemistry. The roots in the Picea glehnii forest were distributed more shallowly than those in the Abies sachalinensis forest, thus avoiding the high water table level as well as the influence of seawater in the soil. The salt marsh showed an extremely high sodium concentration and base saturation, indicating that this area was directly affected by seawater. Recently, the periphery of the Picea glehnii forest on Syunkunitai sand dune has been declining because of seawater inundation caused by ground subsidence.     

Plant regeneration via direct and indirect adventitious shoot formation and chromosome-doubled somaclonal variation in Titanotrichum oldhamii (Hemsl.) Solereder

The gesneriaceous perennial plant Titanotrichum oldhamii has beautiful foliage and attractive bright yellow flowers. However, breeding of T. oldhamii by conventional sexual hybridization may be difficult because sexual reproduction of this species is very rare. In the present study, plant regeneration systems via both direct and indirect formation of adventitious shoots from leaf explants were established as the first step toward breeding T. oldhamii by using biotechnological techniques. Adventitious shoots were formed efficiently on medium containing 0.1 mg l⁻¹ benzyladenine. Histological observation showed that shoot formation on this medium occurred directly from leaf epidermal cells without callus formation. On the other hand, leaf explants formed calluses on medium containing 0.1 mg l⁻¹ 2,4-dichlorophenoxyacetic acid. The calluses could be maintained by monthly subculturing to fresh medium of the same composition. When the calluses were transferred to plant growth regulator-free medium, they formed adventitious shoots. Directly and indirectly formed shoots rooted well on medium containing 0.1 mg l⁻¹ indole-3-butyric acid. Plantlets thus obtained were successfully acclimatized and grew vigorously in the greenhouse. Flow cytometry analysis indicated that no variation in the ploidy level was observed in plants regenerated via direct shoot formation, whereas chromosome doubling occurred in several plants regenerated via indirect shoot formation. Regenerated plants with the same ploidy level as the mother plants showed almost the same phenotype as the mother plants, whereas chromosome-doubled plants showed apparent morphological alterations: they had small and crispate flowers, and round and deep green leaves.     

In <Emphasis Type="Italic">vitro</Emphasis> synthesis of glycogen: the structure,properties, and physiological function of enzymatically-synthesized glycogen

This review describes a new enzymatic method for in vitro glycogen synthesis and its structure and properties. In this method, short-chain amylose is used as the substrate for branching enzymes (BE, EC 2.4.1.18). Although a kidney bean BE and Bacillus cereus BE could not synthesize high-molecular weight glucan, BEs from 6 other bacterial sources produced enzymatically synthesized glycogen (ESG). The BE from Aquifex aeolicus was the most suitable for the production of glycogen with a weight-average molecular weight (M _w) of 3,000–30,000 k. The molecular weight of the ESG is controllable by changing the concentration of the substrate amylose. Furthermore, the addition of amylomaltase (AM, EC 2.4.1.25) significantly enhanced the efficiency of this process, and the yield of ESG reached approximately 65%. Typical preparations of ESG obtained by this method were subjected to structural analyses. The average chain length, interior chain length, and exterior chain length of the ESGs were 8.2–11.6, 2.0–3.3, and 4.2–7.6, respectively. Transmission electron microscopy and intrinsic viscosity measurement showed that the ESG molecules formed spherical particles. Unlike starch, the ESGs were barely degraded by pullulanase. Solutions of ESG were opalescent (milky-white and slightly bluish), and gave a reddishbrown color on the addition of iodine. These analyses revealed that ESG shares similar molecular shapes and solution properties with natural-source glycogen. Moreover, ESG had macrophage-stimulating activity and its activity depends on the molecular weight of ESG. We successfully achieved large scale production of ESG. ESG could lead to new industrial applications, such as in the food, chemical, and pharmaceutical fields.     

Histological Observations on Initiation and Morphogenesis in Immature and Mature Embryo Derived Callus of Barley (Hordeum vulgare L.)

Callus was induced from immature and mature embryos of barley(cv. Haruna Nijo) on Murashige and Skoog medium containing 2mg l^-1 2,4-D and 5 mg l^-1 picloram, respectively. Paraffin sections(10 µm thick) were prepared for histology during callusinitiation and plant regeneration. Meristems were regeneratedfrom nodular compact callus (NC) derived from scutellar epidermisin immature embryos, whereas they were regenerated from NC derivedfrom epidermal cells of leaf or coleoptile bases in mature embryos.Regardless of the explant source, regeneration was predominantlythrough organogenesis, although regeneration through somaticembryogenesis infrequently occurred. Thus, the callus inducedfrom immature and mature embryos of barley was regarded as 'nodularcompact' rather than 'embryogenic'.Copyright 1995, 1999 AcademicPress Barley, callus, Hordeum vulgare, histology, immature embryo, mature embryo, regeneration     

Environmental DNA monitoring method of the commercially important and endangered fish Gnathopogon caerulescens

Limnology - Gnathopogon caerulescens is an endangered but commercially important fish in Lake Biwa, Japan. The population size of G. caerulescens has drastically reduced in the past decades, and...     

Human Pancreatic Tumor Organoids Reveal Loss of Stem Cell Niche Factor Dependence during Disease Progression

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