Comparison of Bacterial Communities Associated with Microcrustaceans from the Floodwater of a Paddy Field Microcosm: Estimation Based on DGGE Pattern and Sequence Analyses     

Ainin Niswati  Jun Murase  Makoto Kimura 《Soil Science and Plant Nutrition》2005,51(2):281-290

Bacterial communities associated with five kinds of microcrustaceans ( Tanycypris sp., Moina sp., Mesocyclops sp., Cypretta sp. and Heterocypris sp.) from the floodwater of a paddy field microcosm were examined by the application of denaturing gradient gel electrophoresis (DGGE) to PCR-amplified 16S rDNA products with universal bacterial primers and by sequencing of characteristic DGGE bands. The number of DGGE bands of the associated bacteria was small, indicating the association of specific bacterial members with the microcrustaceans studied, among which Tanycypris sp. showed the smallest number of bands. Principal component analysis (PCA) demonstrated that the community structure of the associated bacteria could be divided into three groups: Podocopida ( Tanycypris sp., Cypretta sp. and Heterocypris sp.), Moina sp. and Mesocyclops sp., and further analysis separated Tanycypris sp. and Heterocypris sp. into different clusters. The duration of the incubation period affected the bacteria associated with Tanycypris sp., Moina sp. and Cypretta sp. only. Nearly all of the associated bacteria belonged to Gram-negative bacteria, especially the Cytophaga-Flavobacterium-Bacteroides (CFB) group. Closest relatives of the DGGE bands common to three Podocopida and Mesocyclops sp. belonged to an invertebrate endosymbiont.  相似文献   

Carbon cycling in rice field ecosystems in the context of input, decomposition and translocation of organic materials and the fates of their end products (CO₂ and CH₄)     

Makoto Kimura  Jun Murase 《Soil biology & biochemistry》2004,36(9):1399-1416

Rice fields are intensively managed, unique agroecosystems, where soil flooding is general performance for rice cultivation. Flooding the field results in reductive soil conditions, under which decomposition of organic materials proceeds during the period of rice cultivation. A large variety of organic materials are incorporated into rice soils according to field management. In this review, the kind and abundance of organic materials entering carbon cycling in the rice field ecosystem are evaluated first. Then, decomposition of plant residues and soil organic matter in rice fields is reviewed quantitatively. Decomposition of plant residues is shown to be the active process in carbon cycling in rice fields. Rice releases photosynthates into the rhizosphere (rhizodeposition), and they follow a different avenue of decomposition in soil from that of plant residues. Incorporation of rhizodeposition into microbial biomass and soil organic matter during the period of rice cultivation, and their fates after harvesting are evaluated quantitatively from ¹³C pulse labeled experiments. Percolating water transports inorganic and organic carbon from the plow layer to the subsoil layer. The amounts of their transport and accumulation in the subsoil layer are evaluated in relation to the amounts of soil organic C in the plow layer. Not only CO₂ but also CH₄ are produced in the decomposition process of organic materials in flooded rice fields. CH₄ evolution from rice fields is of global concern from the viewpoint of global warming. Origins of CH₄ evolved from rice fields are estimated first, followed by the fates of CH₄ in rice field ecosystems. Rhizodeposition is shown to be the main origin of CH₄ evolved from rice fields. Evolution to the atmosphere is not the sole pathway of CH₄ produced in rice fields. The amounts of CH₄ retained in soil, percolated to the subsoil layer and decomposed in soil are evaluated in the context of the amounts of CH₄ efflux. Thus, this review focuses on carbon cycling in the rice field ecosystem from the viewpoints of input, decomposition, and translocation of organic materials and the fates of their end products (CO₂ and CH₄).  相似文献   

Characteristics of Surface Sediments along a Creek in a Mangrove Forest     

Kazutoshi Kinjo  Yoshihiro Tokashiki  Kazuhiro Sato  Makoto Kitou  Moritaka Shimo 《Soil Science and Plant Nutrition》2005,51(6):809-817

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Soil classification system in the world and application to agriculture and forestry. 7. Application and development of soil classification     

Makoto NAKAI 《Soil Science and Plant Nutrition》2006,52(1):137-137

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Study on some functional and compositional properties of yak butter lipid   总被引：1，自引：0，他引：1  

Dhanapati NEUPANEY  Jin-bo KIM  Makoto ISHIOROSHI  Kunihiko SAMEJIMA 《Animal Science Journal》2003,74(5):391-397

The present experiment was performed to determine some functional properties of yak butter lipids such as lipid class composition; conjugated linoleic acid (CLA) composition, differential scanning calorimetric (DSC) analysis, tyrosinase inhibition activity and antioxidant property. Yak butter lipids composition contained 98% triacylglycerols, 0.9% free fatty acids, 0.32% free sterols and 0.27% phospholipids. The CLA content in yak butter was 2.5% and the major portion was of cis‐9 and trans‐11 (90%). The DSC analysis of yak butter lipids showed a similar path for transition temperature as cow butter lipids, although the enthalpy of yak lipid was higher (40.0 mJ/mg) compared to cow butter lipids (32.0 mJ/mg). Melting point of yak butter was observed at 41°C. Yak butter with lactic acid, NaCl, citric acid and ascorbic acid showed pronounced tyrosinase inhibition activity. Vegetable oils blended with yak butter have extended the oxidation induction time.  相似文献   

Insecticidal activity and microsomal metabolism of biooxidizable lindane analogs     

Makoto Kiso  Masahide Nohta  Keiji Tanaka  Norio Kurihara  Toshio Fujita  Minoru Nakajima 《Pesticide biochemistry and physiology》1977,7(4):341-348

The insecticidal activity of lindane analogs, in which some chlorine atoms were replaced by other groups susceptible to microsomal oxidative metabolism, was determined against mosquitos, house flies, and German cockroaches. When tested with a synergist, piperonyl butoxide, one of the methylthio analogs was as active as lindane, whereas several others were also highly active. By examining the ratio of synergized and unsynergized LD₅₀ values (synergistic ratio value), the highly insecticidal methylthio, methoxy, and methyl analogs appear to undergo metabolic detoxication effectively in house flies. By means of in vitro metabolism experiments using microsomal fraction from house fly abdomen, the methoxy, ethoxy, and methylthio analogs were shown to be metabolized rapidly at similar rates. The synergized insecticidal activities of these compounds against various insect species relate linearly with each other, suggesting that the oxidative degradation is inhibited by the synergist to a similar extent and that the transport process to the site of action is not a limiting factor in determining the relative insecticidal activity.  相似文献   

Effects of serpentine substrate on vegetation and soil development with special reference to Picea glehnii forest in Teshio district, Hokkaido, Japan     

Makoto Nakata  Satoru Kojima 《Forest Ecology and Management》1987,20(3-4):265-290

Characteristics of vegetation and soils in the serpentine area of northern Hokkaido were studied in comparison with non-serpentine areas of the same region, and with other serpentine areas of Japan and elsewhere in the world. The relationship between vegetation and soils is discussed.

Although forest vegetation of northern Hokkaido is generally represented by deciduous forest, coniferous forest, predominantly Picea glehnii, develops in the serpentine area. Deciduous trees are limited both in number and in size. Forest floor is densely covered with Sasa kurilensis. The shrub layer is also well developed, whereas the herb layer is poor but contains characteristic species. Soils developing in the serpentine area are determined as Podzol (Wet Iron Podzol), while Brown Forest Soil is commonly found in the non-serpentine areas of the region. The serpentine soils are shallow and moist, showing general morphology and chemistry of podzolic soil in upper horizons of the profile. In lower horizons, however, physico-chemical properties are strongly affected by the parent rock. In comparison with other serpentine areas of Japan and elsewhere, northern Hokkaido is unique in that the vegetation is represented by a relatively closed forest of fair-sized trees, and the soils by a podzol.

Such Picea glehnii forests and podzolic soils are considered an intrazonal phytogeocoenosis strongly affected by serpentine substrate. In this regard, the cool and humid climate as well as undulating relief of northern Hokkaido are also important factors for the development of the unique phytogeocoenosis.  相似文献   

Differentiation and elimination of uterine natural killer cells in delayed implantation and parturition mice     

Kokubu K  Hondo E  Sakaguchi N  Sagara E  Kiso Y 《The Journal of reproduction and development》2005,51(6):773-776

To clarify the roles of uterine natural killer (uNK) cells in implantation and parturition, differentiation and elimination of uNK cells in the pregnant uterus was examined using artificial delayed implantation (DI) and delayed parturition (DP) mice. To prepare DI mice, pregnant mice were ovariectomized on the third day of pregnancy (D3) and treated with 2 mg progesterone daily. The same amount of progesterone was administered on D15 or D17 of normal pregnant mice at 24 h intervals until sampling to prepare DP mice. The uNK cells contained PAS-positive granules on D8 in DI mice. The uNK cells in DI mice were smaller in size, and differentiation of these cells was delayed compared to those of the control mice. From D19 to D21 in DP mice, the metrial gland was well developed and uNK cells were present. The number of uNK cell granules decreased on D21, and there were no uNK cells in the normal pregnant mice. This result suggests that differentiation of uNK cells is not directly related to implantation, but elimination of these cells is closely involved in parturition.  相似文献   

Male Pseudohermaphroditism in a raccoon dog (Nyctereutes procynoides)     

Weng Q  Murase T  Asano M  Tsubota T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(6):603-605

A wild raccoon dog (Nyctereutes procynoides) which died due to a traffic accident on 18 October 2001, and was determined to be 4.5 years old, was examined. Visual appearance of the external genitalia in this animal showed to be female with a large penis-like clitoris protruding from the vulvar juncture. Visual examination of the internal genitalia revealed that the animal possessed both testes and uterus. Histological appearance of the removed gonads showed only Sertoli cells but no spermatogenesis. Using polymerase chain reaction with skin biopsy directed against the sex-determining region on the Y chromosome (SRY) gene, the genomic SRY gene was expressed as a single band and sequenced. Based on these findings, this raccoon dog was diagnosed as male pseudohermaphrodite.  相似文献   

Changes in activities of enzymes related to energy metabolism in canine lymphoma cells     

Washizu T  Azakami D  Bonkobara M  Washizu M  Arai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(6):615-616

Alterations in the activities of enzymes related to energy metabolism in canine lymphoma cells were investigated. Cytosolic pyruvate kinase (PK) and mitochondrial malate dehydrogenase (MDH) activities in lymphoma cells were significantly higher than those in lymphocytes obtained from lymph nodes of healthy dogs, whereas cytosolic lactate dehydrogenase (LDH) activity was significantly lower in lymphoma cells. The cytosolic M/L ratio (MDH activity/LDH activity), which is considered to be a good indicator of energy metabolism related to glucose utilization in animal tissues, was significantly higher in lymphoma cells than in the normal lymphocytes.  相似文献