Mitochondrial DNA haplogroup D4a is a marker for extreme longevity in Japan

We report results from the analysis of complete mitochondrial DNA (mtDNA) sequences from 112 Japanese semi-supercentenarians (aged above 105 years) combined with previously published data from 96 patients in each of three non-disease phenotypes: centenarians (99-105 years of age), healthy non-obese males, obese young males and four disease phenotypes, diabetics with and without angiopathy, and Alzheimer's and Parkinson's disease patients. We analyze the correlation between mitochondrial polymorphisms and the longevity phenotype using two different methods. We first use an exhaustive algorithm to identify all maximal patterns of polymorphisms shared by at least five individuals and define a significance score for enrichment of the patterns in each phenotype relative to healthy normals. Our study confirms the correlations observed in a previous study showing enrichment of a hierarchy of haplogroups in the D clade for longevity. For the extreme longevity phenotype we see a single statistically significant signal: a progressive enrichment of certain "beneficial" patterns in centenarians and semi-supercentenarians in the D4a haplogroup. We then use Principal Component Spectral Analysis of the SNP-SNP Covariance Matrix to compare the measured eigenvalues to a Null distribution of eigenvalues on Gaussian datasets to determine whether the correlations in the data (due to longevity) arises from some property of the mutations themselves or whether they are due to population structure. The conclusion is that the correlations are entirely due to population structure (phylogenetic tree). We find no signal for a functional mtDNA SNP correlated with longevity. The fact that the correlations are from the population structure suggests that hitch-hiking on autosomal events is a possible explanation for the observed correlations.     

The role of amphibian prey in the diet and growth of giant water bug nymphs in Japanese rice fields

Predatory insects that depend upon particular prey animals are commonly regulated by the prey animal’s abundance. Nymphs of the giant water bug Kirkaldyia (=Lethocerus) deyrolli (Heteroptera: Belostomatidae) are predators regarded as specialists in feeding on tadpoles. We studied the ontogenetic diet shift of aquatic nymphs by quantifying instar abundance and by analyzing captured prey and prey relative abundance during the period of rice irrigation in three localities. We also evaluated the contribution of major prey items (tadpoles, frogs, and Odonata nymphs) on specific growth rates of each nymphal stage in a rearing experiment. First to third-instar nymphs of K. deyrolli fed mainly on tadpoles, regardless of differences in prey availability. Nymphs of subsequent fourth and fifth instar stages shifted from tadpoles to other prey animals within each rice field. A rearing experiment demonstrated that giant water bug nymphs provided with tadpoles had greater specific growth rates at all nymphal stages, except for the final stage, than nymphs fed other prey (frogs and Odonata nymphs). The emergence of young K. deyrolli nymphs seemed to coincide with the period during which tadpoles became abundant in the rice fields. Consumption of tadpoles seems important to allow the nymph to complete its larval development in an unstable temporary habitat. An erratum to this article can be found at     

Differential Responses in Activity of Antioxidant Enzymes to Different Environmental Stresses in Arabidopsis thaliana

Arabidopsis thaliana . Three-week-old plants were exposed to a high temperature (30 C), an enhanced light intensity (200 μE/m²/sec), water deficiency (water deprivation for 2 days), a chilling temperature (5 C), or ultraviolet-B (UV-B) radiation (0.25 or 0.094 W/m²) for 1 week (except for water deficiency). The high temperature and enhanced light treatments increased only dehydroascorbate reductase (DHAR) activity. Water deficiency enhanced the activities of DHAR and guaiacol peroxidase (PER). Chilling temperature increased the activities of ascorbate peroxidase (APX) and glutathione reductase (GR), whereas it decreased catalase (CAT) activity. UV-B at an intensity of 0.25 W/m² elevated the activities of APX, monodehydroascorbate reductase (MDHAR), GR, PER and superoxide dismutase (SOD). It was suggested that the amounts of phenylpropanoid compounds increased during treatments of plants with enhanced light intensity, chilling temperature, and UV-B. These results suggest that some differences exist among the oxidative stress conditions caused by the different treatments, although all of these treatments seem to be related to active oxygen production. We propose that in A. thaliana, environmental stresses may be classified into those which induce DHAR activity and those which induce APX activity. Received 11 January 1999/ Accepted in revised form 22 April 1999     

Effect of an adzuki bean extract on hepatic anti-oxidant enzyme mRNAs in D-galactosamine-treated rats

In acute hepatic injury tests, an adzuki bean extract decreased D-galactosamine (GalN)-induced alterations in the serum alanine aminotransferase and aspartate aminotranferase activities to about 37% and 25%, respectively, although there were no significant differences in these activities between the GalN-treated group with the adzuki bean extract and the GalN-treated group without the adzuki bean extract. Furthermore, the hepatic glutathione peroxidase, glutathione reductase, and Mn- and Cu,Zn-superoxide dismutase mRNA levels in the GalN-treated group with the adzuki bean extract were higher than those in the control group and GalN-treated group without the adzuki bean extract.     

Large-scale general collection of wild-plant DNA in Mustang, Nepal

The deposit of DNA samples of wild plants that correspond to voucher specimens is highly informative and greatly enhances the value of the herbarium specimens. The Society of Himalayan Botany (SHB), Tokyo, has assembled general collections of flowering plants of the Sino-Himalayan region for more than 40 years. In a trial of the collection of these types of bioresources for use in basic research, we adopted FTA cards, which have recently been used for large-scale collection of DNA of humans, microorganisms and viruses, for the general collection of DNA samples of wild plants during a botanical expedition in Mustang, Nepal, in 2003. Three hundred and fifty-five plant specimens from Mustang, Nepal, were collected along with the corresponding DNA samples. Examination of the quality of the DNA samples by PCR demonstrated the utility of the collection system. The identification of all of the specimens collected, as well as data from the specimens, will be presented on the Flora of Nepal Database website (), which is open to the public. The DNA resources will be identified on the website and distributed openly by the SHB to researchers worldwide for basic research.     

Identification of an HLA-A24-restricted OY-TES-1 epitope recognized by cytotoxic T-cells

OY-TES-1 was identified as a human homologue of the mouse, guinea pig, and pig proacrosin binding protein sp32 precursor. Differential expression levels of OY-TES-1 mRNA between testis and other normal tissues, and its expression in cancers indicated that OY-TES-1 would be classified as a cancer/testis antigen and considered to be a candidate of target antigen for cancer immunotherapy. In this study, we showed identification of HLA-A24-binding OY-TES-1 peptide, TES(401-409) (KTPFVSPLL) recognized by CD8 T-cells. Purified CD8 T-cells from healthy donors stimulated in vitro with the peptide-pulsed autologous DC and PBMC produced IFNgamma in response to the peptide-pulsed PBMC and showed cytotoxicity against the peptide-pulsed autologous EBV-B specifically. Furthermore, cytotoxicity was also observed against an OY-TES-1 mRNA-expressing tumor line, LK79. The retention time of the fraction in HPLC of the acid eluate from LK79 cells that showed positive sensitization against autologous EBV-B cells in recognition by CD8 CTL was the same as that of the fraction of the TES(401-409) peptide itself, suggesting that the TES(401-409) was a naturally processed peptide on LK79.     

Stress deprivation simultaneously induces over-expression of interleukin-1beta, tumor necrosis factor-alpha, and transforming growth factor-beta in fibroblasts and mechanical deterioration of the tissue in the patellar tendon

To test the hypothesis that stress deprivation induces over-expression of cytokines in the patellar tendon, 40 rats were divided into the following two groups. In the stress-shielded group, we slackened the patellar tendon in the right knee by drawing the patella toward the tibial tubercle with flexible wires. In the control group, we performed a sham operation on the right knee. Animals were killed at 2 or 6 weeks for immunohistological evaluation and biomechanical examination. For IL-1beta, TNF-alpha and TGF-beta, the ratio of positively stained specimens to total specimens was significantly higher in the stress-shielded tendons than in the control tendons. The elastic modulus of the stress-shielded tendon was significantly lower than that of the control tendon, while the cross-sectional area of the stress-shielded tendon was significantly greater than that of the control tendon. Therefore, the present study indicated that stress shielding induced the over-expression of IL-1beta, TNF-alpha and TGF-beta in patellar tendon fibroblasts with mechanical deterioration of the tendon. Regarding clinical relevance, the present study suggests a possible application of an anti-IL-1beta or anti-TNF-alpha strategy for reducing the mechanical deterioration of tendons and ligaments in response to stress deprivation, although this study did not directly show that over-expression of IL-1beta or TNF-alpha in response to stress deprivation was the causation of mechanical deterioration of tendons.     

Nocardia cyriacigeorgica is a significant pathogen responsible for nocardiosis in Japan and Thailand

Nocardia cyriacigeorgica is a recently described species. During routine diagnostic testing of 121 clinical isolates, we found that about one fourth of the strains from Japan (19 isolates) and Thailand (8 isolates), which were identified in our laboratories as N. asteroides, in fact belong to N. cyriacigeorgica. To our knowledge, this is the first report of infection due to N. cyriacigeorgica in Japan and Thailand, and the third report of infection anywhere in the world. Although N. cyriacigeorgica is usually differentiated from other Nocardia species by utilization of glucose and gluconate, we found that it can also be differentiated by a characteristic synergistic effect between imipenem (IPM) and tobramycin (TOB).