Photosensitivity in mice caused by pyropheophorbide in the midgut gland of the scallop <Emphasis Type="Italic">Patinopecten yessoensis</Emphasis> observed in diarrhetic shellfish poisoning mouse bioassays     

Satoshi Hashimoto  Kenichi Ueno  Kenichi Takahashi  Toshiyuki Suzuki  Yutaka Itabashi 《Fisheries Science》2010,76(3):529-536

Photosensitivity was observed in the mice used in bioassays of diarrhetic shellfish poisoning. The mice were intraperitoneally injected with the extracts from the midgut glands of cultured scallops Patinopecten yessoensis gathered in early spring in Funka Bay, Hokkaido, Japan. The injections induced atypical symptoms in the mice within 24 h. The symptoms included piloerection, substantial eye discharge, swelling of the ears and head, and ear scratching. They were similar to those reported in studies of photosensitivity caused by pyropheophorbide in the midgut glands of abalones, which are herbivorous gastropods. The problematic scallops also accumulated a large amount of pyropheophorbide-a. The amount determined with high-performance liquid chromatography was 300–530 μg per 1 g of the homogenate of the midgut glands. The dose of pyropheophorbide sufficient to cause photosensitivity in a mouse is estimated to be 0.99–2.3 mg per mouse with 20-g body weight. Moreover, comparative tests in mice showed that the onset of the symptoms required light and a substantial amount of pyropheophorbide. Therefore, we determined that the observed symptoms were photosensitivity caused by pyropheophorbide. Scallops, which are suspension-feeding bivalves, can accumulate a large amount of pyropheophorbide in the midgut glands depending on the habitat environment.  相似文献   

Effects of olive leaf powder supplemented to fish feed on muscle protein of red sea bream     

Muh Ali Arsyad  Takashi Akazawa  Chie Nozaki  Makoto Yoshida  Kenichi Oyama  Tatsuo Mukai  Masahiro Ogawa 《Fish physiology and biochemistry》2018,44(5):1299-1308

Olive leaf is known to have the high polyphenol content of 6–9% in dry weight. We investigated the effects of olive leaf powder (OLP) supplemented to fish feed on muscle protein of red sea bream (Pagrus major). Fish reared with feed containing 8% OLP for 40 days had 1.4 times higher myofibril content and 2.2 times higher acid-soluble collagen content than fish reared with control feed for the same period. On the other hand, sarcoplasmic protein content and collagenase activity of the muscle were almost the same between the control fish and OLP-diet fish. Microstructure observation of fish muscle showed that OLP-diet fish has more rigid endomysium structure than that of the control-diet fish. Since collagen fiber in endomysium is responsible for the texture of the muscle, feeding OLP to aquaculture fish will lead to a harder muscle texture. The present study suggests that OLP is a useful feed additive to enhance the texture of aquaculture red sea bream muscle through strengthening of the collagen structure in the muscle.  相似文献   

Current classification of Ralstonia solanacearum and genetic diversity of the strains in Japan     

Mitsuo Horita  Kenichi Tsuchiya  Yasuhiro Suga  Kazutaka Yano  Takamitsu Waki  Daisuke Kurose  Naruto Furuya 《Journal of General Plant Pathology》2014,80(6):455-465

Ralstonia solanacearum is the causal organism of bacterial wilt of more than 200 species representing 50 families of plants in tropical, subtropical, and warm temperate regions in the world. Traditionally classified into five races based on differences in host range, R. solanacearum has also been grouped into six biovars on the basis of biochemical properties. With recent developments in molecular biology, various DNA-based analyses have been introduced and used to confirm that this binary system does not completely represent the diversity within R. solanacearum strains. Therefore, a new hierarchical classification scheme has been suggested, which defines R. solanacearum as a species complex and reorganized the concept of the species as a monophyletic cluster according to a phylogenetic analysis based on genomic sequence data. Here we discuss the current bacterial wilt situation and genetic relationships based on the recent classification system of Japanese R. solanacearum strains as well as worldwide strains. We also review the genetic, biochemical, and pathological characteristics of R. solanacearum strains, in particular, those affecting potato and Zingiberaceae plants as distinctly important pathogens in relation to continuously problematic and recent emergent diseases in Japan.  相似文献   

A new method for evaluating symplastic cadmium absorption in the roots of Solanum melongena using enriched isotopes ¹¹³Cd and ¹¹⁴Cd     

Shinsuke MORI  Akira KAWASAKI  Satoru ISHIKAWA  Tomohito ARAO 《Soil Science and Plant Nutrition》2009,55(2):294-299

Radioisotope techniques are well known as methods for evaluating symplastic ion absorption in roots. In the present study, a new method for evaluating symplastic cadmium (Cd) absorption in plant roots was developed using the enriched isotopes ¹¹³Cd and ¹¹⁴Cd. Seedlings of Solanum melongena were exposed to an enriched isotope solution of ¹¹³Cd at 25°C for 30 min. The roots were excised from each seedling and were then immersed in a cold buffer solution without Cd at 2°C for 120 min to suppress the metabolic activity of the roots. Finally, the roots were treated with a cold buffer solution containing enriched stable isotope ¹¹⁴Cd at 2°C for 120 min, whereby the apoplastically bound ¹¹³Cd was desorbed. We tested the validity of our method for evaluating symplastic Cd in roots compared with the conventional method based on differences in the amount of Cd absorbed at 2°C and 25°C using unlabeled Cd. There was no difference in the symplastic Cd content of the roots between the two methods. These results indicate that it is possible to evaluate the symplastic Cd content in roots using the enriched isotopes ¹¹³Cd and ¹¹⁴Cd.  相似文献   

Contrasting seasonal leaf habits of canopy trees between tropical dry-deciduous and evergreen forests in Thailand     

Ishida A  Diloksumpun S  Ladpala P  Staporn D  Panuthai S  Gamo M  Yazaki K  Ishizuka M  Puangchit L 《Tree physiology》2006,26(5):643-656

We compared differences in leaf properties, leaf gas exchange and photochemical properties between drought-deciduous and evergreen trees in tropical dry forests, where soil nutrients differed but rainfall was similar. Three canopy trees (Shorea siamensis Miq., Xylia xylocarpa (Roxb.) W. Theob. and Vitex peduncularis Wall. ex Schauer) in a drought-deciduous forest and a canopy tree (Hopea ferrea Lanessan) in an evergreen forest were selected. Soil nutrient availability is lower in the evergreen forest than in the deciduous forest. Compared with the evergreen tree, the deciduous trees had shorter leaf life spans, lower leaf masses per area, higher leaf mass-based nitrogen (N) contents, higher leaf mass-based photosynthetic rates (mass-based P(n)), higher leaf N-based P(n), higher daily maximum stomatal conductance (g(s)) and wider conduits in wood xylem. Mass-based P(n) decreased from the wet to the dry season for all species. Following onset of the dry season, daily maximum g(s) and sensitivity of g(s) to leaf-to-air vapor pressure deficit remained relatively unchanged in the deciduous trees, whereas both properties decreased in the evergreen tree during the dry season. Photochemical capacity and non-photochemical quenching (NPQ) of photosystem II (PSII) also remained relatively unchanged in the deciduous trees even after the onset of the dry season. In contrast, photochemical capacity decreased and NPQ increased in the evergreen tree during the dry season, indicating that the leaves coped with prolonged drought by down-regulating PSII. Thus, the drought-avoidant deciduous species were characterized by high N allocation for leaf carbon assimilation, high water use and photoinhibition avoidance, whereas the drought-tolerant evergreen was characterized by low N allocation for leaf carbon assimilation, conservative water use and photoinhibition tolerance.  相似文献   

Extracellular matrix of Magnaporthe oryzae may have a role in host adhesion during fungal penetration and is digested by matrix metalloproteinases     

Kanako Inoue  Tomoko Suzuki  Kenichi Ikeda  Shan Jiang  Naoki Hosogi  Gang-Su Hyon  Sizuka Hida  Taku Yamada  Pyoyun Park 《Journal of General Plant Pathology》2008,74(1):96-96

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Effects of β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin in β‐carotene‐deficient Japanese Black cows          下载免费PDF全文

Yoshitaka Nishijima  Saya Taniguchi  Shuntaro Ikeda  Kenichi Yoshitani  Takashi Hamano  Hiroshi Tani  Masahiko Fujita  Kenji Murakami  Keisuke Kogusa  Kenji Sato  Miki Sugimoto  Shinichi Kume 《Animal Science Journal》2017,88(4):653-658

Data from 18 β‐carotene‐deficient Japanese Black cows were collected to clarify the effects of feeding β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin (Ig) in cows. Cows were assigned to control or carrot groups from 3 weeks before the expected calving date to parturition, and supplemental β‐carotene from dry carrots was 138 mg/day in the carrot group. Plasma β‐carotene concentrations in the control and carrot groups at parturition were 95 and 120 μg/dL, and feeding dry carrots slightly improved plasma β‐carotene at parturition. Feeding dry carrots increased colostral IgA concentrations in cows and tended to increase colostral IgG₁, but colostral IgM, IgG₂, β‐carotene and vitamin A were not affected by the treatment. Feeding dry carrots had no effects on plasma IgG₁, IgA and IgM concentrations in cows, but plasma IgG₁ concentrations decreased rapidly from 3 weeks before the expected calving date to parturition. These results indicate that feeding β‐carotene‐enriched dry carrots is effective to enhance colostral IgA and IgG₁ concentrations in β‐carotene‐deficient cows.  相似文献   

Stage‐specific effects of osmolarity of a culture medium on development of pig oocytes and miniature pig somatic cell nuclear transfer embryos activated by ultrasound treatment     

Yamato MIZOBE  Saori KURINO  Yoshiaki SATA  Hironori MORI  Mitsutoshi YOSHIDA  Kazuchika MIYOSHI 《Animal Science Journal》2010,81(4):453-460

Whether high osmolarity of a culture medium at the early culture stage affects the development of pig oocytes and miniature pig somatic cell nuclear transfer (SCNT) embryos activated by ultrasound was examined. When oocytes were cultured in modified porcine zygote medium‐3 (mPZM‐3) with increased NaCl to 138 mmol/L (mPZM‐3+NaCl; 326 mOsm) or 50 mmol/L sucrose (mPZM‐3+sucrose; 318 mOsm) for the first 2 days and then cultured in normal mPZM‐3 (273 mOsm) for 5 days, the cleavage and blastocyst formation rates were significantly (P < 0.05) higher than those of oocytes cultured in mPZM‐3 for 7 days. The cleavage and blastocyst formation rates of SCNT embryos cultured in mPZM‐3+NaCl for the first 2 days and then cultured in mPZM‐3 for 5 days were also significantly (P < 0.05) higher than those of embryos cultured in mPZM‐3 for 7 days. These results showed that the high osmolarity of a culture medium induced by increasing NaCl concentration during the first 2 days improves the development of pig oocytes and miniature pig SCNT embryos activated by ultrasound.  相似文献   

Comparing the carbon sequestration capacity of temperate deciduous forests between urban and rural landscapes in central Japan     

M.A. Awal  Takeshi Ohta  Kazuho Matsumoto  Tae Toba  Kenichi Daikoku  Shigeaki Hattori  Tetsuya Hiyama  Hotaek Park 《Urban Forestry & Urban Greening》2010,9(3):261-270

Urbanisation is increasing tremendously in some parts of the world. Consequently, many rural forests may become depleted, although many opportunities exist for urban forests to increase. However, few studies have quantified the carbon (C) sequestration capacities of urban and rural forests in specific climatic zones. The present study compared carbon sequestration in two temperate deciduous forests located in Nagoya and Toyota, central Japan. The Nagoya University forest represented an urban forest, and a site in Toyota represented a rural forest. The urban forest at Nagoya University had comparatively smaller areas of green space and larger areas of buildings and roads. Land uses for building and road, which are typical of urban areas, result in smaller diurnal temperature ranges but higher air temperature, vapour pressure deficit, and atmospheric carbon dioxide (CO₂) concentration. The urban forest in this study exhibited higher gross ecosystem exchange (GEE), especially in the active growing season from May to September, suggesting the possible effect of CO₂ fertilisation. However, higher air temperatures caused comparatively smaller net ecosystem exchange (NEE) because of higher ecosystem respiration (RE). Although both forests functioned as CO₂ sinks at annual time scales, the rural Toyota forest site (5.43 t C ha^–1 yr^–1) had 36% higher net ecosystem production (NEP=–NEE; the negative sign indicates uptake by the forest ecosystem from the atmosphere) than that at the urban forest. The higher normalised respiration (i.e., RE/GPP ratio; GPP=–GEE where GPP represents gross primary production) at the Nagoya University forest might be attributable to factors associated with the degree of urbanisation. Thus, in temperate forests, factors associated with urbanisation may reduce the atmospheric carbon sink function by accelerating respiration. This is an issue of global interest, as many countries are experiencing rapid urbanisation.  相似文献   

Pathogenic characters of Japanese potato strains of Ralstonia solanacearum   总被引：1，自引：0，他引：1  

Yasuhiro Suga  Mitsuo Horita  Mizusa Umekita  Naruto Furuya  Kenichi Tsuchiya 《Journal of General Plant Pathology》2013,79(2):110-114

Ralstonia solanacearum (Rs) strains in phylotypes I and IV isolated from potato in Japan were investigated for pathogenicity on potato, tomato, eggplant, Solanum integrifolium, tobacco, groundnut, and pumpkin. The strains were divided into 17 types based on differences in their pathogenicity on the tested plants. Particularly, the pathogenicity of most phylotype I strains on eggplant was distinctly different from that of the phylotype IV strains. When nine potato varieties (included two breeding lines) were inoculated with several Rs strains, phylotype IV strains were highly virulent on the breeding lines that are regarded as resistant to phylotype I strains.  相似文献