Distribution of the Argentine ant, Linepithema humile, along the Seto Inland Sea, western Japan: Result of surveys in 2003–2005

The distribution of the Argentine ant, Linepithema humile, was investigated in 65 cities or towns along the Seto Inland Sea, western Japan in 2003–2005. Our results include all available information of their distribution in Japan until 2005. Argentine ants have invaded Aichi Prefecture (Tahara‐shi), Hyogo Prefecture (Kobe‐shi), Hiroshima Prefecture (Hiroshima‐shi, Fuchu‐cho, Hatsukaichi‐shi, Ono‐cho and Otake‐shi), and Yamaguchi Prefecture (Iwakuni‐shi and Yanai‐shi). The most widespread distribution was found around Hatsukaichi‐shi including the westernmost part of Hiroshima‐shi and the easternmost of Ono‐cho.     

Studies of Unequal Cleavage in Molluscs: I. Nuclear Behavior and Anchorage of a Spindle Pole to Cortex as Revealed by Isolation Technique

Unequal division of the eggs of Spisula solidissima was studied by isolating the nuclear elements. The isolation technique consists mainly of the use of Na-lauryl sulphate with occasional inverting of the container of alcohol-fixed eggs. The procedure was applied to the following stages. (1) germinal vesicles, (2) 1st maturation division, showing anchorage of a spindle pole to the cortex, (3) 2nd meiosis, (4) pronuclear encouter, (5) metaphase, (6) shifting of the metaphase spindle to one side of the cell and a contact with the cortex, (7) ana- and telophase of the 1st division.
Migration and "anchorage" of the spindle to the cortex by one pole is a common phenomenon in unequal divisions of polar body formation and of egg cleavage.     

One-Sided Barrier Impact of an International Railroad on Mongolian Gazelles

Abstract: We conducted a carcass census of Mongolian gazelles (Procapra gutturosa) along the Trans-Mongolian railroad in June 2005. We counted 241 gazelles that had died within the previous 12 months. Carcass numbers were greater on the southwestern side in the northern 3 zones, but we found carcasses only on the northeastern side in the southernmost zone. It suggests that impact of the railroad was stronger on one side and that the strength of this impact varied among regions.     

Trade-off between height growth and stem diameter growth for an evergreen Oak, Quercus glauca, in a mixed hardwood forest

1. Patterns of stem growth of a mid-successional evergreen Oak species ( Quercus glauca ) in a mixed hardwood forest were examined to explore the trade-off relationship between stem-diameter growth and height growth.
2. The mean cross-sectional area (and the corresponding mean diameter) of a stem at a point in time was defined as the stem volume divided by tree height. Based on this definition, a simple equation representing the trade-off relationship between the height growth and mean diameter growth was formulated.
3. In the long term, allocation to height growth was encouraged at the seedling stage and it gradually declined with time, with the decline in the suppressed seedlings being more pronounced than in the dominant trees.
4. However, both the suppressed and the dominant trees showed acceleration of height growth at various ages. Such a fluctuation in the allocation of biomass to height growth is likely to have been caused by chronological changes in light conditions, and meandered the trajectory of allometry between the height and mean diameter.
5. The observed stem growth patterns of the individual trees could explain the chronological changes in the diameter–height relationship of the population.     

Ciliate Protozoa in the Rumen of Sassaby Antelope, Damaliscus lunatus lunatus, Including the Description of a New Species and Form

ABSTRACT. Composition of rumen ciliate fauna in five Zambian, sassaby antelopes was determined. Six genera, 18 species, and four forms were identified. One new species and form, belonging to the subfamily Diplodiniinae, were found, then labeled Ostracodinium damaliscus n. sp. and Diplodinium bubalidis f. aspinosum n. f., respectively. Only ophryoscolecid species were present while isotrichids were absent. Twelve of 18 total species are commmonly found in African antelopes. Three of those 12 species, Entodinium fyferi, Enoploplastron garstangi and Opisthotrichum janus , are only found in African antelopes. Percentage composition was low in the genera ml of rumen fluid, and the average number of ciliate species per host was 17.2.     

The Expression of Tyrosinase,Tyrosinase-Related Proteins 1 and 2 (TRP1 and TRP2), the Silver Protein,and a Melanogenic Inhibitor in Human Melanoma Cells of Differing Melanogenic Activities

The expression of various melanogenic proteins, including tyrosinase, the tyrosinase-related proteins 1 (TRP1) and 2 (TRP2/DOPAchrome tautomerase), and the silver protein in human melanocytes was studied in six different human melanoma cell lines and compared to a mouse derived melanoma cell line. Analysis of the expression of tyrosinase, TRP1, TRP2, and the silver protein using flow cytometry revealed that in general there was a positive correlation between melanin formation and the expression of those melanogenic enzymes. Although several of the melanoma cell lines possessed significant activities of TRP2, the levels of DOPAchrome tautomerase in extracts of human cells were relatively low compared to those in murine melanocytes. Melanins derived from melanotic murine JB/MS cells, from melanotic human Ihara cells and HM-IY cells, from sepia melanin, and from C57BL/6 mouse hair were chemically analyzed. JB/MS cells, as well as Ihara cells and HM-TY cells, possessed significant amounts of 5,6-dihydroxyindole-2-carboxylic acid (DHICA) derived melanins, this being dependent on the activity of TRP2. Kinetic HPLC assays showed that 5,6-dihydroxyindole (DHI) produced during melanogenesis was metabolized quickly to melanin in pigmented KHm-1/4 cells, whereas DHI was stable in amelanotic human SK-MEL-24 cells. A melanogenic inhibitor that has been purified from SK-MEL-24 cells that suppressed oxidation of DHI in the presence or absence of tyrosinase, but had no effect on DHICA oxidation. The sum of these results suggest that the expression of melanogenic enzymes as well as the activity of a melanogenic inhibitor are critical to the production of melanin synthesis in humans.     

Eumelanin and Phaeomelanin Contents of Human Epidermis and Cultured Melanocytes

There are two chemically distinct types of melanin: the red-yellow phaeomelanins and the brown-black eumelanins. While both melanins have been detected in human epidermis and cultured melanocytes, it is unknown how the phaeomelanin/eumelanin ratio in human melanocytes maintained in vitro relates to that in the epidermis from which they were isolated. This study uses high-performance liquid chromatography to quantify the eumelanin and phaeomelanin contents of epidermis and/or cultured melanocytes from 12 Europeans with lightly pigmented skin and 9 non-Europeans with more deeply pigmented skin. Epidermis from non-Europeans contained the highest levels of both eumelanin and phaeomelanin and had the lowest phaeomelanin/eumelanin ratios. In contrast, while cultured melanocytes from non-Europeans also had higher levels of eumelanin and phaeomelanin than melanocytes from Europeans, there was no difference in the phaeomelanin/eumelanin ratios in the two groups. However, the phaeomelanin/eumelanin ratios were higher in the cultured melanocytes than in the corresponding epidermis so that while eumelanin was the predominant melanin in the epidermis, phaeomelanin was the major melanin in the cultured melanocytes. These observations may have important implications for the use of cultured human melanocytes in the study of melanogenesis in man.