The role of river confluences and meanderings in preserving local hot spots for threatened plant species in riparian ecosystems

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Amino acid-chelate: a better source of Zn, Mn and Cu for rainbow trout, Oncorhynchus mykiss

This study aimed to evaluate the amino acid-chelated trace elements as dietary supplement to rainbow trout. Three diets were formulated containing trace elements either from the inorganic salt (SF) or amino acid-chelate (AM). Diets 1 (SF) and 2 (AM) contained the same amount of trace elements from inorganic and amino acid-chelates, respectively. Diet 3 (AM-Hf) was added with trace elements from amino acid-chelatex at one-half of their levels in Diets 1 and 2. Each diet was fed for 15 weeks to three groups of 30 fish each, with an average weight of 1.52±0.21 g. Growth of fish was not affected by the treatment (P>0.05). However, bone (P<0.01) and liver (P<0.05) Cu contents were higher in the AM than the SF group. Similarly, hematocrit level (P<0.05) and alkaline phosphatase (ALP) activity (P<0.01) were higher in the chelate-fed fish. Further, DNA polymerase and CuZnSOD expression in the AM group was highly upregulated (P<0.05) compared to the SF fed fish as quantified by RT-PCR. Absorption and whole body retention of Mn and Zn from the AM were higher (P<0.05) than the inorganic salt. Half supplementation of those fed the elements from AM was at par with the full provision from the inorganic source tested.     

Identification of Bphs,an autoimmune disease locus,as histamine receptor H1

Bphs controls Bordetella pertussis toxin (PTX)-induced vasoactive amine sensitization elicited by histamine (VAASH) and has an established role in autoimmunity. We report that congenic mapping links Bphs to the histamine H1 receptor gene (Hrh1/H1R) and that H1R differs at three amino acid residues in VAASH-susceptible and -resistant mice. Hrh1-/- mice are protected from VAASH, which can be restored by genetic complementation with a susceptible Bphs/Hrh1 allele, and experimental allergic encephalomyelitis and autoimmune orchitis due to immune deviation. Thus, natural alleles of Hrh1 control both the autoimmune T cell and vascular responses regulated by histamine after PTX sensitization.     

Extracellular protease production of bacteriolytic bacteria isolated from marine environments

ABSTRACT:   Fourteen bacterial strains isolated from marine environments exhibited antagonistic action against a wide range of bacteria including Vibrio spp. A double layer agar method was used for preliminary screening to determine the relative degree of growth inhibition or bacteriolysis exhibited by the isolates. Most of the antagonistic isolates were found to be Gram-negative, motile rods and were oxidase positive, and oxidative in the oxidation and fermentation test, suggesting that they are belong to the genera Pseudomonas . The antagonistic isolates lyzed the dead cells of marine Gram-negative bacteria in both plate and liquid methods. Bacteriolytic and casein hydrolytic activities were observed in the culture supernatant of the isolates. Anion exchange column chromatography (Toyopearl DEAE-650 M) was used to purify the extracellular protease produced by an antagonistic strain A1-J25a. The active fractions of protease collected from the eluted solution also exhibited bacteriolytic activity.     

Self-feeding activity of a pleuronectiform fish, the barfin flounder

The self-feeding activity of the barfin flounder (Verasper moseri) was examined under natural photoperiod and temperature. The experiment, carried out over 12 weeks from September to December, involved tagged fish (mean body weight: 371 g) reared in three 1000-l tanks (3 or 5 fish per tank) with a self-feeder device. The sensor comprised a switch and trigger string with a bead. Self-feeding activity was recorded in all tanks from day 1. The fish fed mostly at night. Strong positive correlations were observed between the number of daily feeder activations and water temperature/photoperiod, and all fish grew during the experiment. These results demonstrate that barfin flounder can operate self-feeding systems and it is suggested that self-feeding activity is influenced by photoperiod and water temperature.     

A New and Simple Technique for the Isolation of Plasma Membrane Lipids from Root-Tips

It has been suggested that plasma membrane (PM) lipids play a major role in aluminum (Al) tolerance; however, no direct investigations have been carried out using PM lipids from root-tips. Here we report a new technique for PM isolation as an alternative to the laborious two-polymer phase partitioning method that is commonly applied, as follows: 1) separation of protoplasts from 1-cm root-tip portions by enzymatic digestion, 2) attachment of the purified protoplasts to glass plates coated with polylysine, 3) preparation of PM ghosts by successive burst of the attached protoplasts using three separate buffer solutions (25 mM PIPES, 5 mM EDTA, and 2 mM MgCl₂, at pH 7.0) with slow stirring for 60 s. The PMs were confirmed to be devoid of organelle membranes by fluorescence microscopy, thin layer chromatography (TLC) and western blot analysis. The PM lipids obtained were found to be useful for studies on their differential permeability and lipid composition between lines of triticale or cultivars of maize under Al stress.     

Effect of Simulated Acid Rain on Deterioration of Concrete

In the study the long-term exposure tests to simulated acid rain were performed in order to clarify the effect of acid rain on deterioration of concrete. Mortar specimens with 40 mm in width, 15 mm in thickness and 160 mm in length were used for the tests. At each time after the fixed rainfall was attained, those were tested physically and analyzed chemically. Finally total rainfall of 9000mm was given to the specimens. From the test results, it was confirmed that the eroded depth of the specimen has a good linear relation to the total rainfall under simulated acid rain with various pH. Surface erosion rates of the mortar specimens with an ordinary mix proportion under simulated acid rains with pH 3.0 and 2.5 were about 1.2 and three times larger than that under pH 5.6, respectively. It was also confirmed that flexural strength of the specimens with an ordinary mix proportion hardly changed under low pH simulated acid rain even after total rainfall of 9000mm was given.