Measurements of density contrast and sound-speed contrast for target strength estimation of Neocalanus copepods (Neocalanus cristatus and Neocalanus plumchrus) in the North Pacific Ocean     

Ryuichi Matsukura  Hiroki Yasuma  Hiroto Murase  Shiroh Yonezaki  Tetsuichiro Funamoto  Satoshi Honda  Kazushi Miyashita 《Fisheries Science》2009,75(6):1377-1387

The mass density and sound-speed contrasts against surrounding seawater (g and h, respectively) of Neocalanus copepods (N. cristatus and N. plumchrus) were measured in 2006 and 2007 to compute the theoretical target strength (TS). The values of g ranged from 0.997 to 1.009 in N. cristatus and from 0.995 to 1.009 in N. plumchrus. There were no correlations between prosome length (PL) and g. The values of h ranged from 1.006 to 1.021 in N. cristatus and from 1.013 to 1.025 in N. plumchrus and varied with changes in temperature. TS was estimated with the theoretical sound scattering model using the values of g and h based on the temperature, salinity, and depth of the location where the specimens were collected. Regressions of the tilt-averaged TS versus PL were obtained at 38, 120, and 200 kHz. The averaged TS of N. cristatus and N. plumchrus at 120 kHz, which is widely used as a high frequency, ranged from −110.0 to −103.1 dB and from −121.4 to −109.7 dB, respectively. There was a positive correlation between frequency and averaged TS: the higher the frequency, the higher the value of averaged TS. The TS at 120 and 38 kHz varied from 14.8 to 16.4 dB in N. cristatus and from 17.9 to 18.7 dB in N. plumchrus, respectively; that at 200 and 120 kHz varied from 2.9 to 5.5 dB in N. cristatus and from 5.3 to 6.5 dB in N. plumchrus, respectively.  相似文献   

cDNA cloning and primary structure comparison of tauropine dehydrogenase and β-alanopine dehydrogenase from the limpet <Emphasis Type="Italic">Cellana grata</Emphasis>     

Noriyuki Endo  Hiroto Matsu-ura  Nobuhiro Kan-no 《Fisheries Science》2009,75(6):1471-1479

The primary structures of β-alanopine dehydrogenase (β-AlDH) and tauropine dehydrogenase (TaDH) from the limpet Cellana grata were determined by amino acid sequence analysis and complementary DNA (cDNA) cloning. β-AlDH and TaDH cDNAs comprised 1,479 nucleotides and 1,444 nucleotides, respectively, and both included an open reading frame of 1,206 nucleotides corresponding to 402 amino acids. The enzymes showed very high homology, with 96% amino acid identity. These enzymes were homologous to other marine invertebrate opine dehydrogenases (OpDHs), except TaDH of the marine sponge Halichondria japonica. The highest homologies were to alanopine dehydrogenase from Fusitriton oregonensis, being 57% for both enzymes. A phylogenetic tree constructed on the basis of marine invertebrate OpDHs and developed using a sequence distance method and neighbor-joining algorithm showed a tendency for the classification of animals from taxonomically derived evolutionary trees. Additionally, Cellana grata OpDHs belong to the same group as the Gastropoda OpDHs. This represents the first report concerning the primary structure of marine invertebrate β-AlDH, and primary structure comparisons of clearly different enzymes from the same species.  相似文献   

Effect of the methoxyiminoacetamide fungicide,SSF129, on respiratory activity in Botrytis cinerea     

Hiroto Tamura  Akira Mizutani  Hideo Yukioka  Nobuo Miki  Katsuaki Ohba  Michio Masuko 《Pest management science》1999,55(7):681-686

(E)-2-Methoxyimino-N-methyl-2-[2-(2,5-dimethylphenoxymethyl)phenyl]acetamide (SSF129) has been developed as a broad-spectrum systemic fungicide for control of cereal and fruit diseases. This compound inhibited NADH-oxidation by submitochondrial particles from mycelial cells of Botrytis cinerea, with an EC₅₀ value of 14.5 nM , due to blockage of electron transport through the cytochrome bc₁ complex in the mitochondrial respiratory chain. However, SSF129 did not suppress, but rather increased, oxygen consumption by mycelial cells of the fungus. This was because mycelial cells contain an alternative oxidase protein and the cells have the ability to rapidly switch electron flux from the main cytochrome pathway to the alternative pathway on blockage of the former by SSF129. The alternative pathway of the mycelia seems not to be operative when the cytochrome pathway is functional. Naturally occurring flavonoids inhibited the alternative oxidase of the mycelial cells in a dose-dependent manner, with EC₅₀ values of 68.4 µM for flavone and 63.7 µM for flavanone. These observations suggested that plant components play an important role in control of gray mould by SSF129. © 1999 Society of Chemical Industry  相似文献   

Rj (rj) genes involved in nitrogen-fixing root nodule formation in soybean     

Masaki Hayashi  Yuichi Saeki  Michiyo Haga  Kyuya Harada  Hiroshi Kouchi  Yosuke Umehara 《Breeding Science》2012,61(5):544-553

It has long been known that formation of symbiotic root nodules in soybean (Glycine max (L.) Merr.) is controlled by several host genes referred to as Rj (rj) genes, but molecular cloning of these genes has been hampered by soybean’s complicated genome structure and large genome size. Progress in molecular identification of legume genes involved in root nodule symbiosis have been mostly achieved by using two model legumes, Lotus japonicus and Medicago truncatula, that have relatively simple and small genomes and are capable of molecular transfection. However, recent development of resources for soybean molecular genetic research, such as genome sequencing, large EST databases, and high-density linkage maps, have enabled us to isolate several Rj genes. This progress has been achieved in connection with systematic utilization of the information obtained from molecular genetics of the model legumes. In this review, we summarize the current status of knowledge of host-controlled nodulation in soybean based on information from recent studies on Rj genes, and discuss the future research prospects.  相似文献   

Satellite tracking of Bryde’s whales Balaenoptera edeni in the offshore western North Pacific in summer 2006 and 2008     

Hiroto Murase  Tsutomu Tamura  Seiji Otani  Shigetoshi Nishiwaki 《Fisheries Science》2016,82(1):35-45

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Endocarditis in chickens caused by subclinical infection of Streptococcus gallolyticus subsp. gallolyticus     

Sekizaki T  Nishiya H  Nakajima S  Nishizono M  Kawano M  Okura M  Takamatsu D  Nishino H  Ishiji T  Osawa R 《Avian diseases》2008,52(1):183-186

Streptococcus gallolyticus subsp. gallolyticus causes endocarditis in humans and acute septicemia in domestic birds. We describe here the infective endocarditis caused by the bacterium found among clinically healthy broilers at two abattoirs in Japan. The chickens were thought to be healthy because of the lack of clinical symptoms and normal levels of mortality before slaughtering. At the time of inspection, some chickens were condemned because of organ disorders characterized by vegetative valvular endocarditis as well as focal necrosis in heart, liver, and spleen. Streptococcus gallolyticus subsp. gallolyticus was isolated from the organs as a pure culture, indicating that the bacterium probably was the causative agent of the disorders. Amplified fragment length polymorphism analysis of the isolates collected at the abattoirs from chickens grown in nine different farms indicated that the isolates were different variants of the same clonal lineage and may have been derived from the same ancestor. These results suggest that S. gallolyticus subsp. gallolyticus causes infectious endocarditis in chickens and that healthy chickens may possess the bacterium in their normal flora as an opportunistic pathogen.  相似文献   

Indole-3-carbaldehyde: a tyrosinase inhibitor from fungus YL185     

Kuniyoshi Shimizu  Xinglian Geng  Mika Hashiguchi  Hiroto Suhara  Syoko Fukunaga  Seiji Yasutake  Ryuichiro Kondo  Mototake Tsutsui  Ikuo Sato 《Journal of Wood Science》2003,49(4):349-354

Indole-3-carbaldehyde (1) was isolated as a tyrosinase inhibitor from the ethyl acetate-soluble fraction of extracellular fluids of unknown fungus YL185. The partial sequencing data of 18S ribosomal DNA (18S rDNA) indicate that this isolate belongs to the family Polyporaceae or Corticiaceae sensu lato. Indole-3-carbaldehyde inhibited the oxidation of l-3,4-dihydroxyphenylalanine (l-DOPA) by mushroom tyrosinase with a 50% inhibitory concentration (IC₅₀) of 1.3mM and showed inhibitory activity on melanin production in B16 melanoma cells. The aldehyde group of 1 plays an important role in eliciting tyrosinase inhibitory activity.  相似文献   

Modulation of gut microbiota associated with abalone Haliotis gigantea by dietary administration of host-derived Pediococcus sp. Ab1     

Shunpei Iehata  Miyo Nakano  Reiji Tanaka  Hiroto Maeda 《Fisheries Science》2014,80(2):323-331

In the present study, we evaluated how dietary administration of host-derived Pediococcus sp. Ab1 has an effect on the abalone gut microbiota using a culture-dependent method and 16S rRNA gene library analysis. The culturable lactic acid bacteria number in the probiotic sample was 10⁵ higher than that in the non-probiotic sample, and we speculate that this significant increase was due to colonization of Ab1 into abalone gut. The result of a culture-dependent method showed that the proportion of Vibrio halioticoli clade, which is known to be a beneficial resident bacterium to abalone, was much higher in the probiotic sample than in the non-probiotic sample. 16S rRNA gene clone sequences revealed that gut microbiota in the probiotic sample was obviously diverse compared to the non-probiotic sample, probably due to improvement of the gut environment by Ab1 colonization. In addition, some beneficial bacteria–like sequences such as V. halioticoli were only found in the probiotic sample. These results suggest that the dietary administration of Ab1 to abalone gut has a great effect on modulation of not only culturable but also unculturable gut microbiota. Our results are useful for future investigations into understanding the effect of probiotics on gut microbiota.  相似文献   

黔中山地2种喀斯特森林对降雨量分配和降雨中离子浓度的影响     

李克之  张喜  户田诰夫  许笑天  生原喜久雄  田野  崔迎春 《中国林副特产》2008,(2):1-7

黔中山地2种喀斯特森林的林冠截留总量均值为76.36mm、灌草层截留总量均值为435.75mm、净地表径流总量均值为11.06mm、90cm壤中流量均值为10.76mm、蒸发及其它量均值为509.75mm,其相对值为7.32%、41.76%、1.06%、1.03%、48.84%,与其它森林类型对降雨量的影响模式明显不同。不同喀斯特森林类型对随降雨流动的Ca^2＋,Mg^2＋,K^＋,Na^＋,Cl^-,NO3^-,NH4^＋,SO4^2-有稀释或积聚作用,主要受森林树种组成和结构以及土壤类型的影响,这为利用喀斯特森林改善水质、净化空气提供了依据。除马尾松树干径流中所测离子浓度均有积聚作用外,杨树、枫香、樟和冬青对部分离子有积聚作用、对另一部分离子有稀释作用,因树种而异。相对于林外降雨,林内降雨中离子浓度增大的有Ca^2＋、Mg^2＋、K^＋、NH4^＋、SO4^2-、NO3^-、降低的有Na^＋,地表径流中所测离子浓度均增大,相应集水区溪流中离子浓度增大的有Ca^2＋、Mg^2＋、Na^＋、NO3^-、降低的有K^＋、NH4^＋、SO4^2-。黑色石灰土和黄色石灰土对90cm壤中流的离子浓度有不同效应,二者均具有集聚作用的是Ca^2＋、Mg^2＋、SO4^2-、稀释作用的是NO3^-。Cl^-在喀斯特森林降雨中的规律性较差。  相似文献   

Evaluation of Short-term Myelotoxicity Study in Dietary Reduced Rats     

Asanuma F  Miyata H  Iwaki Y  Kimura M  Matsumoto K 《Journal of toxicologic pathology》2010,23(1):31-37

This study attempted to prove our hypothesis that a short-term toxicity study, using a 4-day dosing regimen as an example, is suitable for evaluating myelotoxicity in rats. We compared the hematological, bone marrow cytological and histopathological results of 5-fluorouracil (5-FU) treated and pair-feeding groups after a 4-day administration period. Several experimental groups were defined for this 4-day study as well as for our previously reported 14-day study (Miyata et al., 2009); these included 5-FU treated groups receiving 12, 15 and 18 mg/kg/day (FU12, FU15 and FU18), pair-feeding groups (R12, R15 and R18 receiving the same amount of food as the FU12, FU15 and FU18 groups, respectively) and a nontreated control group. Although severe reductions in body weight gain and food consumption were reported in the 14-day study, only slight reductions were observed in the 4-day study. In the 4-day study, a decrease in blood reticulocytes and a decreasing trend of marrow erythroid cells were only observed in the FU18 group, and no effects were observed in the pair-feeding groups. The erythroblastic changes observed in this 4-day study were thought to reflect the direct influence of 5-FU administration. Since concerns regarding the influence of secondary changes related to undernutrition were minimized in the 4-day study, it was thought to clarify the direct influence of 5-FU administration on erythroblastic cells. Thus, a 4-day study protocol might be helpful for distinguishing secondary changes related to undernutrition.  相似文献