Absolute configurations of pittosporatobiraside A and B from Pittosporum tobira

The absolute configuration at C-12 of pittosporatobiraside A and B isolated from the leaves of Pittosporum tobira was determined to be S on the basis of the exciton chirality of their dibenzoate derivative. The structures of the two glycosides were thus established to be (1S,9S,10S,11S,12S,14R,16R)-12-[(Z)-2-methyl-1-oxo-2-butenyl]-6,14-dimethyl-2-methylene-9-(1-methylethyl)-15,17-dioxatricyclo[8.7.0.0^11,16]heptadec-5-en-13-one and (1S,9S,10S,11S,12S,14R,16R)-12-(3-methyl-1-oxo-2-butenyl)-6,14-dimethyl-2-methylene-9-(1-methylethyl)-15,17-dioxatricyclo [8.7.0.0^11,16]heptadec-5-en-13-one, respectively.     

Studies on DNA markers (D4S10 and D4S43/S127) genetically linked to Huntington's disease in Japanese families

Summary This is the first full report on the genetic linkage between Japanese Huntington's disease and the DNA markers D4S10 and D4S43/S127. With use of the HindIII, BglI, and EcoRI polymorphisms detected at D4S10, and the combination of all these polymorphisms to give composite haplotypes, nine Japanese Huntington's disease families were found to be informative. Three recombinants for D4S10 were detected in these families, giving a maximum lod score of 1.662 at a of 0.10. Similarly, when we used the MspI and PvuII polymorphisms detected by D4S43/S127, five families gave informative results. No recombinant was detected in these families, giving a maximum lod score of 3.348 at a of 0.00. These results clearly support the view that the Japanese Huntington's disease gene may be identical with the Western gene, in spite of the lower prevalence rate in Japan.     

Two pathways of iron uptake in bovine spleen apoferritin dependent on iron concentration

Iron incorporation by bovine spleen apoferritin either with ferrous ammonium sulfate in different buffers or with ferrous ammonium sulfate and phosphate was studied. Iron uptake and iron autoxidation were recorded spectrophotomerically. The buffers [4-(2-hydroxyethyl)-1-piperazinyl]ethanesulphonic acid (Hepes) and tris(hydroxymethyl)aminoethane (Tris) exhibited pH-dependent iron autoxidation, with Tris showing less iron autoxidation than Hepes. An Eadie-Scatchard plot (v/[s] versus v) of the iron uptake rate in Hepes was a curved rather than a straight line, suggesting that there are two iron uptake pathways. On the other hand, the Eadie-Scatchard plots of Tris and of Hepes after the addition of phosphate showed a straight line. Phosphate accelerated the iron uptake rate. The iron loading kinetics of apoferritin in Hepes was dependent on apoferritin concentration. The K_m value obtained from iron uptake kinetics was 4.5 M, corresponding to the physiological iron concentration. These results demonstrate that iron loading of apoferritin was accomplished at physiological iron concentrations, which is essential for iron uptake, via two uptake pathways of dependent on iron concentration.     

Origin of the plastid in the anomalously pigmented dinoflagellate Gymnodinium mikimotoi (Gymnodiniales, Dinophyta) as inferred from phylogenetic analysis based on the gene encoding the large subunit of form I-type RuBisCO

The dinoflagellate Gymnodinium mikimotoi Miyake et Kominami ex Oda possesses an anomalously pigmented plastid which contains 19′‐hexanoyloxyfucoxanthin, 19′‐butanoyloxyfucoxanthin and fucoxanthin instead of peridinin as the major carotenoids. Previously, we have shown that the plastid of G. mikimotoi belongs to the rhodoplast lineage as inferred from phylogenetic analyses based on the amino acid sequences deduced from psbA and psaA and the nucleotide sequence of the plastid small subunit ribosomal RNA. Furthermore, in the present study, we cloned and sequenced an additional representative plastid gene, rbcL, encoding the large subunit of ribulose 1–5 bisphosphate carboxylase/oxygenase (RuBisCO LSU) from G. mikimotoi. The amino acid sequence deduced from the rbcL gene of G. mikimotoi apparently revealed the conventional form I RuBisCO LSU, which is present in most photosynthetic organisms, and not the divergent form II existing in typically pigmented dinofl age Nates with plastids containing peridinin as the main carotenoid. This finding supports the hypothesis that the origins of the plastids in G. mikimotoi and peridinin‐type dinoflagellates are not related to each other. Molecular phylogenetic analysis based on the amino acid sequence deduced from the rbcL gene further showed that the plastid of G. mikimotoi belongs to the rhodoplast lineage. In particular, G. mikimotoi clustered with haptophytes in the phylogenetic tree. From this result, two hypotheses with respect to the origin of the plastid in G. mikimotoi can be proposed: G. mikimotoi may have engulfed a haptophyte‐like cell (tertiary symbiosis) or englulfed a rhodophyte‐like cell that was closely related to the origin of the plastid in the haptophyte (secondary symbiosis).     

Molecular evidence suggesting interspecific hybridization in Zoanthus spp. (Anthozoa: Hexacorallia)

Interspecific hybridization has been proposed as a possible explanation for the incredible diversity seen in reef-dwelling corals, but until now little proof of such hybridization in other reef-dwelling anthozoans has been reported. Without further observation of hybridization, the question of such a phenomenon being widespread in Anthozoa remains. Here we have examined the mitochondrial cytochrome oxidase I gene (COI) and the nuclear internal transcribed spacer of ribosomal DNA (ITS-rDNA) from three species of the mass-spawning, encrusting anemone genus Zoanthus (Z. sansibaricus, Z. kuroshio, Z. gigantus) to investigate possible hybridization. The three species coexist at two of three sampling locations in southern Japan. Zoanthus spp. ITS-rDNA region spacers (ITS-1 and ITS-2) were shown to have very high rates of divergence. At locations where all three species co-existed, several of our sampled Z. sansibaricus individuals (with identical "sansi" COI sequences) possessed two very divergent (i.e., species-level difference) ITS-rDNA alleles, the expected "sansi" allele and the divergent "B" allele. Additionally, two Z. sansibaricus individuals possessed only "B" alleles despite having "sansi" COI sequences. These results indicate that Z. sansibaricus has possibly experienced interspecific hybridization at least once with a Zoanthus partner possessing the "B" allele, and that these resulting hybrids may also sexually reproduce, demonstrating potential hybridization occurring in the order Zoantharia (Hexacorallia).     

Diversity of microbial eukaryotes in sediment at a deep-sea methane cold seep: surveys of ribosomal DNA libraries from raw sediment samples and two enrichment cultures

Recent culture-independent surveys of eukaryotic small-subunit ribosomal DNA (SSU rDNA) from many environments have unveiled unexpectedly high diversity of microbial eukaryotes (microeukaryotes) at various taxonomic levels. However, such surveys were most probably biased by various technical difficulties, resulting in underestimation of microeukaryotic diversity. In the present study on oxygen-depleted sediment from a deep-sea methane cold seep of Sagami Bay, Japan, we surveyed the diversity of eukaryotic rDNA in raw sediment samples and in two enrichment cultures. More than half of all clones recovered from the raw sediment samples were of the basidiomycetous fungus Cryptococcus curvatus. Among other clones, phylotypes of eukaryotic parasites, such as Apicomplexa, Ichthyosporea, and Phytomyxea, were identified. On the other hand, we observed a marked difference in phylotype composition in the enrichment samples. Several phylotypes belonging to heterotrophic stramenopiles were frequently found in one enrichment culture, while a phylotype of Excavata previously detected at a deep-sea hydrothermal vent dominated the other. We successfully established a clonal culture of this excavate flagellate. Since these phylotypes were not identified in the raw sediment samples, the approach incorporating a cultivation step successfully found at least a fraction of the “hidden” microeukaryotic diversity in the environment examined. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Wheat bran protects Fischer-344 rats from diquat-induced oxidative stress by activating antioxidant system: selenium as an antioxidant

Wheat bran had a protective effect against diquat toxicity in rats fed a purified diet (PD). We studied the effects of wheat bran on the antioxidant system in the liver of rats treated with saline and diquat. Although feeding wheat bran did not affect the concentration of hepatic non-protein sulfhydryl or the activity of glucose 6-phosphate dehydrogenase in the saline-injected rats, these values were significantly higher in the rats fed PD containing wheat bran (W-PD) than in rats fed only PD after administering diquat. The glutathione peroxidase and reductase activities were significantly elevated by wheat bran in the saline-injected rats. Although the glutathione peroxidase activity was unchanged in both the PD-fed rats and W-PD-fed rats after the diquat treatment, the glutathione reductase activity was significantly decreased in both the PD-fed and W-PD-fed rats. Feeding the rats with PD containing 0.15 ppm selenium as well as with W-PD elevated the activity of hepatic glutathione peroxidase and attenuated the diquat toxicity. These results indicate that wheat bran protected against diquat toxicity by activating the hepatic antioxidant system, and that selenium was the key antioxidant in wheat bran.     

Amyloid β induces adhesion of erythrocytes to endothelial cells and affects endothelial viability and functionality

It has been suggested that amyloid β-peptide (Aβ) might mediate the adhesion of erythrocytes to the endothelium which could disrupt the properties of endothelial cells. We provide evidence here that Aβ actually induced the binding of erythrocytes to endothelial cells and decreased endothelial viability, perhaps by the generation of oxidative and inflammatory stress. These changes are likely to contribute to the pathogenesis of Alzheimer's disease.     

Development of a new class of benzoylpyrrole-based PPARα/γ activators

Starting with a subtle blood glucose-lowering effect of a TGF-β inhibitor, we designed and synthesized a series of benzoylpyrrole-based carboxylic acids as PPARs activators. Among these compounds, 10sNa exhibited favorable blood glucose-lowering effect without body weight gain. We assume that the beneficial effect of 10sNa is attributed to not only its compound PPARα agonistic activity but also its PPARγ partial agonistic activity.     

Identification of Biological Properties of Intralymphatic Tumor Related to the Development of Lymph Node Metastasis in Lung Adenocarcinoma

Background

Intralymphatic tumors in the extratumoral area are considered to represent the preceding phase of lymph node metastasis. The aim of this study was to clarify the biological properties of intralymphatic tumors susceptible to the development of lymph node metastasis, with special reference to the expression of cancer initiating/stem cell (CIC/CSC) related markers in cancer cells and the number of infiltrating stromal cells.

Material and Methods

Primary lung adenocarcinomas with lymphatic permeation in the extratumoral area were retrospectively examined (n = 107). We examined the expression levels of CIC/CSC related markers including ALDH1, OCT4, NANOG, SOX2 and Caveolin-1 in the intralymphatic cancer cells to evaluate their relationship to lymph node metastasis. Moreover, the number of infiltrating stromal cells expressing CD34, α-smooth muscle actin, and CD204 were also evaluated.

Results

Among the intralymphatic tissues, low ALDH1 expression in cancer cells, high SOX2 expression in cancer cells, and a high number of CD204(+) macrophages were independent predictive factors for lymph node metastasis (P = 0.004, P = 0.008, and P = 0.028, respectively). Among these factors, only low ALDH1 expression in cancer cells was significantly correlated with the farther spreading of lymph node metastasis (mediastinal lymph node, pathological N2) (P = 0.046) and the metastatic lymph node ratio (metastatic/resected) (P = 0.028). On the other hand, in the primary tumors, ALDH1 expression in the cancer cells was not associated with lymph node metastasis. Intralymphatic cancer cells expressing low ALDH1 levels exhibited lower E-cadherin expression levels than cancer cells with high levels of ALDH1 expression (P = 0.015).

Conclusions

Intralymphatic cancer cells expressing low levels of ALDH1 and infiltrating macrophages expressing CD204 have a critical impact on lymph node metastasis. Our study also highlighted the significance of evaluating the biological properties of intralymphatic tumors for tumor metastasis.