Atkinsiella parasitica sp. nov. isolated from a rotifer,Brachionus plicatilis

A new species ofAtkinsiella (Lagenidiales, Oomycetes),Atkinsiella parasitica is described and illustrated. It was isolated from the eggs and bodies of a rotifer,Brachionus plicatilis, with fungal infection in 1992. The rotifer was reared in a hatchery as the first food supply for seed production of crustaceans and fishes. The fungus is characterized by producing monoplanetic, lateral biflagellate zoospores, and infrequently branched discharge tubes. Optimum temperature for the fungus was 25°C. The fungus was considered an obligate marine fungus, because its growth was observed only on PYGS medium including seawater.     

Clasping structure in the double cone of the retina of the turtle (Gyoclemys reevesii)

Summary The double cone of the turtle retina was reconstructed three-dimensionally from electron micrographs of 400 serial sections. Cytoplasm of the accessory cone extends bilaterally to surround the principal cone incompletely. The cytoplasmic extensions are 0.1 m in width and 2 m in length at their longest portions. They arise at approximately the median portion of the ellipsoid (consisting of mitochondria) and terminate at the level of the outer limiting membrane. The possible function of these extensions as a clasping structure is discussed.     

Lagenidium myophilum infection in the coonstripe shrimp,Pandalus hypsinotus

A fungal infection occurred in juvenile coonstripe shrimps,Pandalus hypsinotus, cultured at Hokkaido Institute of Mariculture, Hokkaido, Japan. The fungus was identified asLagenidium myophilum, the same fungus that had previously been isolated from the abdominal muscle of adult northern shrimps,Pandalus borealis, and larvae of the coonstripe shrimp. Histopathologically, numerous nonseptate hyphae were observed in the lesions, and melanized hemocytes were present within the blackened areas. The optimum temperature for growth of the present strain was 25–30°C, and the optimum NaCl concentration for growth was 0.5–1.0%. Its biological characteristics were compared with those ofLagenidium myophilum isolated from diseased larval coonstripe shrimp and adult northern shrimp. The fungus was pathogenic toward shrimps of the genusPandalus, which live in deep sea areas. The fungus could infect shrimps at various stages, from larva to adult.     

Ovarian Cancer Stem Cells Are Enriched in Side Population and Aldehyde Dehydrogenase Bright Overlapping Population

Cancer stem-like cells (CSCs)/cancer-initiaiting cells (CICs) are defined as a small population of cancer cells that have self-renewal capacity, differentiation potential and high tumor-initiating ability. CSCs/CICs of ovarian cancer have been isolated by side population (SP) analysis, ALDEFLUOR assay and using cell surface markers. However, these approaches are not definitive markers for CSCs/CICs, and it is necessary to refine recent methods for identifying more highly purified CSCs/CICs. In this study, we analyzed SP cells and aldehyde dehydrogenese bright (ALDH^Br) cells from ovarian cancer cells. Both SP cells and ALDH^Br cells exhibited higher tumor-initiating ability and higher expression level of a stem cell marker, sex determining region Y-box 2 (SOX2), than those of main population (MP) cells and ALDH^Low cells, respectively. We analyzed an SP and ALDH^Br overlapping population (SP/ALDH^Br), and the SP/ALDH^Br population exhibited higher tumor-initiating ability than that of SP cells or ALDH^Br cells, enabling initiation of tumor with as few as 10² cells. Furthermore, SP/ADLH^Br population showed higher sphere-forming ability, cisplatin resistance, adipocyte differentiation ability and expression of SOX2 than those of SP/ALDH^Low, MP/ALDH^Br and MP/ALDH^Low cells. Gene knockdown of SOX2 suppressed the tumor-initiation of ovarian cancer cells. An SP/ALDH^Br population was detected in several gynecological cancer cells with ratios of 0.1% for HEC—1 endometrioid adenocarcinoma cells to 1% for MCAS ovary mucinous adenocarcinoma cells. Taken together, use of the SP and ALDH^Br overlapping population is a promising approach to isolate highly purified CSCs/CICs and SOX2 might be a novel functional marker for ovarian CSCs/CICs.     

Active Bacterial Populations and Grazing Impact Revealed by an In Situ Experiment in a Shallow Aquifer

To elucidate bacterial population dynamics in an aquifer, we attempted to reveal the impact of protozoan grazing on bacterial productivity and community structure by an in situ incubation experiment using a diffusion chamber. The abundance and vertical distribution of bacteria and protozoa in the aquifer were revealed using wells that were drilled in a sedimentary rock system in Itako, Ibaraki, Japan. The water column in the wells possessed aerobic and anaerobic layers. Active bacterial populations under the grazing pressure of protozoa were revealed through in situ incubation with grazer eliminating experiment by the filtration. On August 19, 2003, the total number of bacteria (TDC) decreased from 1.5 × 10⁶ cells ml^{? 1} at 2.2 m depth to 3.0 × 10⁵ cells ml^{? 1} at 10 m depth. The relative contribution of the domain Bacteria to TDC ranged between 63% and 84%. Protozoa existed at a density of 4.2 × 10⁴ to 1.9 × 10⁵ cells ml^{? 1} in both aerobic and microaerobic conditions. A grazing elimination experiment in situ for 6 days brought about clearly different bacterial community profiles between the 2.2 m and 10 m samples. The bacterial composition of the initial community was predominantly β- and γ -proteobacteria at 2.2 m, while at 10 m β-, α - and γ -proteobacteria represented 56%, 26% and 13% of the community, respectively. The distribution of bacterial abundance, community composition and growth rates in the subsurface were influenced by grazing as well as by geochemical factors (dissolved oxygen and concentrations of organic carbon, methane and sulfate). Results of the in situ incubation experiment suggested that protozoan grazing contributes significantly to bacterial population dynamics.     

Circular causality in integrative multi-scale systems biology and its interaction with traditional medicine

This paper discusses the concept of circular causality in “biological relativity” (Noble, Interface Focus. 2, 56-64, 2012) in the context of integrative and multi-scale systems approaches to biology. It also discusses the relationship between systems biology and traditional medicine (sometimes called scholarly medical traditions) mainly from East Asia and India. Systems biology helps illuminate circular processes identified in traditional medicine, while the systems concept of attractors in complex systems will also be important in analysing dynamic balance in the body processes that traditional medicine is concerned with. Ways of nudging disordered processes towards good attractors through the use of traditional medicines can lead to the development of new ways not only of curing disease but also of its prevention. Examples are given of cost-effective multi-component remedies that use integrative ideas derived from traditional medicine.     

Secular trends of sizes at birth in Japanese healthy infants born between 1962 and 1988

Body sizes at birth are important clinical indicators widely used for evaluation of prenatal growth. Japan had significant socioeconomic improvement around the 1960s, and these environmental changes may influence physiologically prenatal growth. Furthermore, in Japan, measurements of size at birth for birth certificates are weight and height. Thus, we can refer to annual data on weight and height, but not on head and chest circumference at birth. In this study we measured the weight, height, and head and chest circumference at birth among 6,563 Japanese singleton healthy infants, annually in 1962 and 1988, and examined secular trends of these anthropometric measurements. The boys consistently exceeded the girls in all four variables. Birth weight and height increased significantly from the 1960s to '70s, but did not differ between the '70s and '80s in both boys and girls. Secular trends of head and chest circumference were different from them. In both boys and girls, head and chest circumference increased significantly from the '60s to the '70s, but decreased significantly from the '70s to the '80s. No difference of head circumference during the '60s and '80s was found, but the difference of chest circumference was found. Size at birth was likely to increase from the '60s to '70s in Japan. These findings suggest that the environmental changes such as socioeconomic improvements influence the prenatal growth.     

Ebselen inhibits NO-induced apoptosis of differentiated PC12 cells via inhibition of ASK1-p38 MAPK-p53 and JNK signaling and activation of p44/42 MAPK and Bcl-2

Ebselen, a selenium-containing heterocyclic compound, prevents ischemia-induced cell death. However, the molecular mechanism through which ebselen exerts its cytoprotective effect remains to be elucidated. Using sodium nitroprusside (SNP) as a nitric oxide (NO) donor, we show here that ebselen potently inhibits NO-induced apoptosis of differentiated PC12 cells. This was associated with inhibition of NO-induced phosphatidyl Serine exposure, cytochrome c release, and caspase-3 activation by ebselen. Analysis of key apoptotic regulators during NO-induced apoptosis of differentiated PC12 cells showed that ebselen blocks the activation of the apoptosis signaling-regulating kinase 1 (ASK1), and inhibits phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-jun N-terminal protein kinase (JNK). Moreover, ebselen inhibits NO-induced p53 phosphorylation at Ser15 and c-Jun phosphorylation at Ser63 and Ser73. It appears that inhibition of p38 MAPK and p53 phosphorylation by ebselen occurs via a thiol-redox-dependent mechanism. Interestingly, ebselen also activates p44/42 MAPK, and inhibits the downregulation of the antiapoptotic protein Bcl-2 in SNP-treated PC12 cells. Together, these findings suggest that ebselen protects neuronal cells from NO cytotoxicity by reciprocally regulating the apoptotic and antiapoptotic signaling cascades.     

Effects of quantity and quality of dietary protein on the brain polysome profile in aged rats

The purpose of this study was to determine whether the quantity and quality of dietary protein affected the polysome profile of the brain in aged rats. Two experiments were done on three groups of aged rats (30 wk) given the diets containing 20% casein, 5% casein, or 0% casein (experiment 1), and 20% casein, 20% gluten, or 20% gelatin (experiment 2) for 10 d. The aggregation in brain ribosomes declined with a decrease of quantity and quality of dietary protein except in the hippocampus. The RNA concentration (mg RNA/g protein) did not differ among the three groups varying the dietary protein in any brain regions. The results suggest that the higher quantity and quality of dietary protein improves the polysome profile in the brain of aged rats, and that the polysome profile is at least partly related to the mechanism by which the dietary protein affects brain protein synthesis in aged rats.