Synthesis and Structure−Activity Relationship of Omaezallene Derivatives

Omaezallene derivatives (nor‐bromoallene, nor‐bromodiene, and bromoenynes) were successfully synthesized. Their antifouling activity and toxicity to the cypris larvae of the barnacle Amphibalanus amphitrite and ecotoxicity to the marine crustacean Tigriopus japonicus were studied. It was revealed that the two side chains of omaezallene were essential to its antifouling activity because the activities of nor‐bromoallene and nor‐bromodiene were significantly diminished. The bromoenyne was found to exhibit potent antifouling activities comparable to omaezallene with low toxicity and ecotoxicity. Preparation of bromoenyne framework is much easier than that of bromodiene moiety in omaezallene. Based on the antifouling activities of the bromoenynes, the synthesis of fluorescent probes and evaluation of their biological activities were also carried out.     

The effects of peroxovanadate and peroxovanadyl on glucose metabolism in vivo and identification of signal transduction proteins involved in the mechanism of action in isolated soleus muscle

The insulin-like effects of peroxovanate (POV) and peroxovanadyl (PSV) on rates of lactate formation and glycogen synthesis were measured in isolated incubated soleus muscle preparations. In another experiment rats were made insulin deficient by streptozotocin injection and treated with POV and PSV (0.25 mM) administered in the drinking water and in the course of 7 days glycemia were determined. Also, signal transduction proteins ERK 1 and ERK 2 involved in the insulin signaling were measured in soleus muscle of diabetic rats treated with POV and PSV. Peroxides of vanadate and vanadyl significantly stimulated glucose utilization in soleus muscle preparations in vitro. The stimulation of glycogen synthesis and lactate formation by POV and PSV was similar to insulin stimuli. Rats treated with POV or PSV presented reduction of glycemia, food and fluid intake with amelioration of the diabetic state during the short period of treatment (7 days). POV and PSV modulated ERK1/2 phosphorilation and the insulin administration in these rats caused an addictive effect on phosphorilation state of these proteins.     

Lymphocytes transfer [14C]‐labeled fatty acids to skeletal muscle in culture; modulation by exercise

Previous studies have shown that lipids are transferred from lymphocytes (Ly) to different cell types including macrophages, enterocytes, and pancreatic β cells in co‐culture. This study investigated whether [¹⁴C]‐labeled fatty acids (FA) can be transferred from Ly to skeletal muscle (SM), and the effects of exercise on such phenomenon. Ly obtained from exercised (EX) and control (C) male Wistar rats were preloaded with the [¹⁴C]‐labeled free FA palmitic (PA), oleic (OA), linoleic (LA), or arachidonic (AA). Radioactively loaded Ly were then co‐cultured with SM from the same Ly donor animals. Substantial amounts of FA were transferred to SM being the profile PA = OA > AA > LA to the C group, and PA > OA > LA > AA to the EX group. These FA were incorporated predominantly as phospholipids (PA = 66.75%; OA = 63.09%; LA = 43.86%; AA = 47.40%) in the C group and (PA = 63.99% OA = 52.72%; LA = 55.99%; AA = 63.40%) in the EX group. Also in this group, the remaining radioactivity from AA, LA, and OA acids was mainly incorporated in structural and energetic lipids. These results support the hypothesis that Ly are able to export lipids to SM in co‐culture. Furthermore, exercise modulates the lipid transference profile, and its incorporation on SM. The overall significance of this phenomenon in vivo remains to be elucidated. Copyright © 2010 John Wiley & Sons, Ltd.     

Poly-ethers from Winogradskyella poriferorum: Antifouling potential, time-course study of production and natural abundance

A sponge-associated bacterium, Winogradskyella poriferorum strain UST030701-295T was cultured up to 100 l for extraction of antifouling bioactive compounds. Five poly-ethers were isolated and partially characterized based on nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS); two of them showed inhibitory effects on biofilm formation of marine bacteria and larval settlement of macro-foulers but did not produce any adverse effects on the phenotypes of zebra fish embryos at a concentration of 5 μg ml⁻¹. The effect of culture duration on the production of the poly-ethers and the bioactivity of the relevant extracts was monitored over a period of 12 days. The total crude poly-ether production increased from day 2 to day 5 and the highest bioactivity was observed on day 3. The poly-ethers were found to be localized in the cellular fraction of the extracts, implying their natural occurrence. The potent bioactivity of these poly-ethers together with their high natural abundance in bacteria makes them promising candidates as ingredients in antifouling applications.     

Estimation of in vivo bone mineral density (BMD) and shape characterization for diagnosing osteoporosis by ultrasonic inspection.

A new method for estimating in vivo bone mineral density (BMD) and characterizing the shape of cancellous bone has been proposed using the results of ultrasonic inspection for the diagnosis of osteoporosis. The method is based on two-dimensional bone area fraction S (percent bone area between bone and bone marrow) calculated from the difference in the speed of ultrasonic wave propagation through cancellous bone. It was shown that the two-dimensional area fraction of a heel bone gives a good relationship to the BMD by DXA (dual energy x-ray absorptiometry) testing of human heel bone (calcaneus) and spine (vertebrae lumbar), as expressed by the relation, BMD (g/cm2) = 0.0167S for heel bone (r = 0.83), and BMD (g/cm2) = 0.0254S + 0.123 for the spine (r = 0.77). Shape characterization is based on the image simulation procedure employing eight random variables from a computer and the statistical results of fractal analysis for numerous cancellous bone patterns. We also demonstrate the validity of the shape characterization using autopsy specimens as a diagnostic tool for osteoporosis.     

Species-specific detection and quantification of common barnacle larvae from the Japanese coast using quantitative real-time PCR

Species-specific detection and quantification methods for barnacle larvae using quantitative real-time polymerase chain reaction (qPCR) were developed. Species-specific primers for qPCR were designed for 13 barnacle species in the mitochondrial 12S ribosomal RNA gene region. Primer specificity was examined by PCR using template DNA extracted from each of the 13 barnacle species, other unidentified barnacle species, and field collected zooplankton samples. The resulting PCR products comprised single bands following agarose gel electrophoresis when the templates corresponded to primers. The amplifications were highly species-specific even for the field plankton samples. The field plankton samples were subjected to qPCR assay. The calculated DNA contents for each barnacle species were closely correlated with the number of larvae measured by microscopic examination. The method could be applied to quantify barnacle larvae in natural plankton samples.     

Species-specific detection and quantification of common barnacle larvae from the Japanese coast using quantitative real-time PCR

Species-specific detection and quantification methods for barnacle larvae using quantitative real-time polymerase chain reaction (qPCR) were developed. Species-specific primers for qPCR were designed for 13 barnacle species in the mitochondrial 12S ribosomal RNA gene region. Primer specificity was examined by PCR using template DNA extracted from each of the 13 barnacle species, other unidentified barnacle species, and field collected zooplankton samples. The resulting PCR products comprised single bands following agarose gel electrophoresis when the templates corresponded to primers. The amplifications were highly species-specific even for the field plankton samples. The field plankton samples were subjected to qPCR assay. The calculated DNA contents for each barnacle species were closely correlated with the number of larvae measured by microscopic examination. The method could be applied to quantify barnacle larvae in natural plankton samples.     

Isocyanides Derived from α,α‐Disubstituted Amino Acids: Synthesis and Antifouling Activity Assessment

Herein, we contribute to the development of environmentally friendly antifoulants by synthesizing eighteen isocyanides derived from α,α‐disubstituted amino acids and evaluating their antifouling activity/toxicity against the cypris larvae of the Balanus amphitrite barnacle. Almost all isocyanides showed good antifouling activity without significant toxicity and exhibited EC₅₀ values of 0.07 – 7.30 μg/mL after 120‐h exposure. The lowest EC₅₀ values were observed for valine‐, methionine‐, and phenylalanine‐derived isocyanides, which achieved > 95% cypris larvae settlement inhibition at concentrations of less than 30 μg/mL without exhibiting significant toxicity. Thus, the prepared isocyanides should be useful for further research focused on the development of environmentally friendly antifouling agents.     

Anti-barnacle activity of novel simple alkyl isocyanides derived from citronellol

Twenty novel simple alkyl isocyanides derived from citronellol were synthesized and evaluated for their antifouling activity and toxicity against cypris larvae of the barnacle, Balanus amphitrite. The anti-barnacle activity of the synthesized isocyanides was in the EC(50) range of 0.08-1.49 μg ml(-1). Simple isocyanides containing a benzoate and chloro group showed the most potent anti-barnacle activity. In addition, none of the synthesized compounds showed significant toxicity and LC(50) values were <10 μg ml(-1). The LC(50)/EC(50) ratios of almost all of the synthesized compounds were >10(2). The results indicate that these simple isocyanides are promising low-toxicity antifouling agents.