East-west comparison of the zooplankton community in the subarctic Pacific during summers of 2003-2006

The subarctic Pacific is known to have east-west gradients in the oceanic environment and phytoplankton community. The western subarctic Pacific is characterized by low temperature and high chlorophyll-a while the eastern region by high temperature and low chlorophyll-a. Although there is little information on the differences in the zooplankton community between the eastern and western subarctic Pacific, the gradients in the oceanographic environment and phytoplankton community may markedly affect the zooplankton community in this region. The aim of this study is to clarify east-west differences in the subarctic Pacific zooplankton community. Zooplankton were sampled at stations along the 165°E line (western subarctic Pacific from 41°30'N to 49°30'N) and 165°W line (eastern subarctic Pacific from 39°N to 53°30'N) using 0.335 and 0.100 mm mesh size Twin NORPAC net during the summers of 2003-2006. East-west differences in the zooplankton community were characterized as: 1) greater total zooplankton abundance in the west-and 2) larger body size of calanoid copepods within same copepodid stage in the west. Differences in east-west zooplankton abundances are attributed to differences in the magnitude of primary production (high in the west) and the size of primary producers (large in the west). Larger body sizes of calanoid copepods in the west are attributed to the lower temperature. Thus, differences in zooplankton abundance and body size are concluded to be due to east-west gradients in the oceanographic environment and phytoplankton community

Mesenchymal Stromal Cells Perspective: New Potential Therapeutic for the Treatment of Neurological Diseases

Several studies have shown that mesenchymal stromal/stem cells (MSCs) exert their neuroprotective and neurorestorative efficacy via the secretion of neurotrophic factors. Based on these studies, many clinical trials using MSCs for the treatment of neurological disorders have been conducted, and results regarding their feasibility and efficacy have been reported. The present review aims to highlight the characteristics and basic research regarding the role of MSCs in neurological disease and to discuss the recent progress in clinical trials using MSCs to treat various neurological disorders

Comparing the vertical distribution of iron in the eastern and western North Pacific Ocean

Labile dissolved Fe (<0.22 μm) in the western (165°E) and eastern (165°W) North Pacific Ocean had nutrient- and apparent oxygen utilization (AOU)-like profiles characterized by surface depletion and deep enrichment (5–3000 m depth). Dissolved Fe concentrations in the deep-water column at the mid-latitudes were approximately one-half lower in the eastern region (0.5–0.8 nM) than in the western region (0.8–1.3 nM) although the dissolved Fe concentrations in the surface mixed layer in both regions were extremely depleted to 0.1–0.2 nM. Surprisingly, the labile particulate Fe concentrations (≤∼0.1 nM, total dissolvable Fe minus labile dissolved Fe) throughout the water column at low latitudes in the eastern region were extremely lower than those (∼0.5–1 nM) in the western region. It is suggested that the low Fe levels in the eastern mid-latitude oceanic region are primarily due to the lower atmospheric Fe supply in the eastern region.An edited version of this paper was published by AGU. Copyright 2006, American Geophysical Union, Geophysical Research Letters, 200

Abundance, biomass and body size of the hydromedusa Aglantha digitale in the western and eastern subarctic Pacific during the summers of 2003-2006

The aim of this study is to evaluate regional and interannual changes in abundance, biomass and body size of the hydromedusa Aglantha digitale in the subarctic Pacific. A. digitale was sampled by 0–150 m vertical tows using a 100 μm mesh-size NORPAC net at stations from 41°30′N to 49°30′N along the 165°E line (western subarctic Pacific) and from 39°00′N to 53°30′N along the 165°W line (eastern subarctic Pacific) during the summers of 2003–2006. The mean numerical abundances during the course of the study in the west and east were 32.9 (range, 0–368) and 169.2 (0–768) ind. m^－2, respectively, and those of biomass were 26.3 (0–264) and 69.1 (0–418) mg DM m^－2, respectively. The abundance and biomass showed no significant north-south or year-to-year differences within each transect but they were significantly greater in the east in some years. The body size was characterized with the dominance of small-sized individuals in the east. The higher abundance and biomass, and smaller body size in the east were probably due to sampling during or just after their reproduction in the east