Synthesis and insecticidal activity of nitroguanidine derivatives

Nitroguanidine derivatives with thiazol-5-ylmethyl moieties were prepared and their insecticidal activities against homopterous pests were tested. New synthetic routes for 2-chloro-5-chloromethylthiazole from 2,3-dichloro-1-propene and for substituted nitroguanidines from S-methyl-N-nitroisothiourea were established. Biological evaluation led to a novel insecticide (E)-1-(2-chlorothiazol-5-ylmethyl)-3-methyl-2-nitroguani dine (TI-435) which has a broad activity spectrum and is under development. ©1999 Society of Chemical Industry     

Sorption and desorption studies of Cs and Sr in contaminated soil samples around Fukushima Daiichi Nuclear Power Plant

Journal of Soils and Sediments - Huge amounts of radiocesium, radiostrontium, and fission products were released into the atmosphere during the Fukushima Daiichi Nuclear Power Plant (FDNPP)...     

Validation of the usefulness of 26S rDNA D1/D2, internal transcribed spacer, and intergenic spacer 1 for molecular epidemiological analysis of Macrorhabdus ornithogaster

Macrorhabdus ornithogaster (MO) is an infectious fungus that causes gastric damage in birds. In this study, we established nested and seminested polymerase chain reaction (PCR) methods that specifically amplify the domain D1/D2 region (D1/D2) of 26S ribosomal DNA (rDNA), internal transcribed spacer (ITS) of rDNA, and intergenic spacer (IGS) 1 region from avian feces. Phylogenetic analysis of MO collected from Japanese pet birds showed little genetic variation; analysis based on these regions did not distinguish between host species order, differences in MO shape, or host gastrointestinal symptoms. These regions were found to be unsuitable for molecular epidemiological studies of MO and further investigation into other genetic regions is required.     

Pathological features of hepatic portal venous gas in a cat

An 8-year 8-month-old castrated male Munchkin presented with vomiting, anorexia and hypoactivity. Computed tomography revealed excessive gas accumulation within the intestinal lumen and gas bubbles in the liver, spleen, and portal venous system, indicating hepatic portal venous gas. The cat died without any significant improvement, and mild splenomegaly was found at necropsy. Histologically, multiple gas vacuoles were diffusely observed in the liver and spleen. In the stomach, multiple gas vacuoles and scattered focal ulcers were detected within the mucosa. Multifocal hemorrhage was noted in the small and large intestines, whereas gas vacuoles were not present. Based on these findings, a gastric ulcer under high gas pressure may have provided an entry point for gas into the portal venous system.     

Thermal gelation properties of white croaker, walleye pollack and deepsea bonefish surimi after suwari treatment at various temperatures

The effects of setting (suwari) at around 40 °C on the breaking strength and breaking strain rate of thermal gels treated at 85 °C for 20 min during the following processing step were examined in association with the polymerization and degradation of myosin heavy chains (MHCs) for surimi prepared from white croaker, walleye pollack and deepsea bonefish. In the case of white croaker and walleye pollack, maximum values of breaking strength and breaking strain rate were obtained after suwari at 30–40 °C for both 30 and 60 min, at which temperature MHCs were polymerized. In comparison, these textual properties of the thermal gels decreased in surimi prepared from deepsea bonefish after suwari at around 38 °C for 30 min and at around 32 °C for 60 min, with concomitant degradation products of MHC. The textual properties of deepsea bonefish after suwari at temperatures >45 °C tended to be almost the same as those after suwari at temperatures of <30 °C, where neither polymerization nor degradation of MHC was observed.     

The first success of glass eel production in the world: basic biology on fish reproduction advances new applied technology in aquaculture

The eel has long been esteemed as an important food fish in the world, especially in Japan, and has been used as an experimental fish for many fields of fish physiology. However, the decreases in eel resources have been a serious concern in recent years. The catches of glass eels as seedlings for aquaculture have shown a long-term decrease in both Europe and East Asia. To increase eel resources, the development of techniques for artificial induction of maturation and spawning and rearing their larvae have been eagerly desired. Recent progress of reproductive physiology of fish, especially mechanisms of oocyte maturation and ovulation in female and of spermatozoa maturation in male, facilitate to establish techniques for hormonal induction of maturation and spawning in sexually immature eels. With persistent effort to development of rearing techniques of larvae, we have first succeeded to produce glass eel. These applied techniques are may contribute to understand the basic reproductive physiology of the eel.     

Distribution of adipocyte-related cells in skeletal muscle of rainbow trout Oncorhynchus mykiss

Adiponectin is one of the adipokines secreted mainly from adipocytes in mammals. In rainbow trout, however, adiponectin is highly expressed in skeletal muscle. Although it has been suggested that fish skeletal muscle contains adipocytes, their endocrine function and distribution are poorly understood. Recently, an EST analysis of rainbow trout found that heart-type fatty acid binding protein (H-FABP), a member of the intracellular fatty acid binding protein family, encodes an adipose-specific gene. In this study, we produced anti-adiponectin and H-FABP antibodies and investigated the distribution of adipocytes and related cells in skeletal muscle of rainbow trout. The adiponectin signal was detected at around 75 kDa in muscle in Western blotting. Since the molecular mass of rainbow trout adiponectin is around 25 kDa, this 75 kDa band would be a trimer. For H-FABP, the signal band was detected at around 15 kDa. Immunohistochemistry of skeletal muscle sections indicated that adiponectin and H-FABP signals were present outside of muscle cells and throughout the muscle tissues, suggesting the existence of adipocyte-related cells in these regions. These results will contribute to our understanding of energy metabolism in fish skeletal muscle.     

Administration of tetrodotoxin protects artificially raised juvenile tiger puffer <Emphasis Type="Italic">Takifugu rubripes</Emphasis> from predators

We examined the effects of tetrodotoxin (TTX) administration on artificially raised tiger puffer Takifugu rubripes juvenile survival after release into a mesocosm with predators to clarify the ecological significance of TTX. Pellets containing three different concentrations of TTX [0 as the control, 7 and 14 mouse units (MU)/g diet] were fed to non-toxic artificially raised T. rubripes juveniles for 10 days. TTX accumulation in the various tissues of fish was detected except for in the control diet group. TTX administration did not affect survival or growth of the fish. One hundred fish from each diet group were released together after TTX administration into a salt pond mesocosm (2650 m²) with predators (Lateolabrax sp.) for 5 days. Survival after release was significantly higher in both the fish fed with the 7 MU TTX/g diet (62%) and the 14 MU TTX/g diet (74%) than in the control fish (32%).     

Hen egg yolk and skinned krill as possible foods for rearing leptocephalus larvae of Anguilla japonica Temminck & Schlegel

Usual diets for rearing leptocephalus larvae of Japanese eel Anguilla japonica include eggs of the endangered spiny dogfish Squalus acanthias (SE). We investigated the effects of alternative food materials, hen egg yolk (HEY) and exoskeleton‐free (skinned) Antarctic krill (SAK), on the growth and survival of eel larvae. We found that feed comprising whole krill including exoskeleton (WAK) containing higher levels of fluoride (37.89 mg kg^?1) was acutely toxic to eel larvae exposed to this alone. In contrast, extract from SAK containing lower concentrations of fluoride (4.25 mg kg^?1) showed no apparent adverse effects. Growth of larvae fed a mixture of SE and SAK in a feed trial of 58 days [mean body weight (BW), 6.0 mg] was about twofold higher than that of larvae fed a mixture of SE and WAK (3.2 mg) (P < 0.01). A mixture of HEY and SAK also had some dietary benefits for eel larvae, enabling them to survive for up to 58 days and to grow significantly (mean BW, 2.4 mg), compared with their initial weight (mean BW, 0.2 mg) (P < 0.001). Although additional nutritional improvements are needed, the present results suggest that combination diet HEY and SAK may be a good alternative to SE as an effective diet for eel larvae.