Toward metrological traceability for DNA fragment ratios in GM quantification. 1. Effect of DNA extraction methods on the quantitative determination of Bt176 corn by real-time PCR     

Corbisier P  Broothaerts W  Gioria S  Schimmel H  Burns M  Baoutina A  Emslie KR  Furui S  Kurosawa Y  Holden MJ  Kim HH  Lee YM  Kawaharasaki M  Sin D  Wang J 《Journal of agricultural and food chemistry》2007,55(9):3249-3257

An international CCQM-P60 pilot study involving eight national metrological institutes was organized to investigate if the quantification of genetically modified (GM) corn powder by real-time PCR was affected by the DNA extraction method applied. Four commonly used extraction methods were compared for the extraction of DNA from a GM Bt176 corn powder. The CTAB-based method yielded the highest DNA template quantity and quality. A difference in the 260 nm/230 nm absorbance ratio was observed among the different extraction methods. Real-time amplification of sequences specific for endogenous genes zein and hmg as well as transgenic sequences within the cryIA(b) gene and a fragment covering the junction between the transformed DNA and the plant genome were used to determine the GM percentage. The detection of the transgenic gene was affected by the quantity and quality of template used for the PCR reaction. The Bt176 percentages measured on diluted or purified templates were statistically different depending on the extraction method applied.  相似文献   

Phylogenetic study on a bacterial community in the floodwater of a Japanese paddy field estimated by sequencing 16S rDNA fragments after denaturing gradient gel electrophoresis     

Taketoshi Shibagaki-Shimizu  Natsuko Nakayama  Yasunori Nakajima  Kazuo Matsuya  Makoto Kimura  Susumu Asakawa 《Biology and Fertility of Soils》2006,42(4):362-365

Phylogenetic positions of characteristic bands of 16S rDNA that were obtained from the floodwater of a Japanese paddy field by denaturing gradient gel electrophoresis (DGGE) analysis in a previous work (Biol Fertil Soils 36:306–312, 2002) were determined to identify dominant bacterial members in the floodwater. Sequences of DGGE bands were affiliated with the Cytophaga–Flavobacterium–Bacteroides group, β-Proteobacteria, and Actinobacteria and showed phylogenetically close relationships with species inhabiting other aquatic environments, although most of their closest relatives were uncultured bacterial clones.  相似文献   

Fractionation of N₂O isotopomers during production by denitrifier     

Sakae Toyoda  Hidenori Mutobe  Naohiro Yoshida  Yasunori Tanji 《Soil biology & biochemistry》2005,37(8):1535-1545

Isotopomer ratios of N₂O, which include intramolecular ¹⁵N-site preference in addition to conventional isotope ratios for N and O in NNO (we designate N^α and N^β for the center and end N atom, respectively, in the asymmetric molecule), reflect production and consumption processes of this greenhouse gas. Therefore, they are useful parameters for deducing global N₂O budget. This paper reports the first precise measurement of ¹⁵N-site preference in N₂O produced by two species of denitrifying bacteria, Pseudomonas fluorescens (ATCC 13525) and Paracoccus denitrificans (ATCC 17741).Cultures were incubated in a batch mode with a liquid medium that contains KNO₃ as unique nitrogen supply under acetylene/helium (10% v/v) atmosphere at 27 °C. Enrichment factors for ¹⁵N in bulk nitrogen in N₂O (average for N^α and N^β) fluctuated in a few tens permil showing a slight difference between the species. In contrast, ¹⁵N-site preference (difference in isotope ratios between N^α and N^β) showed nearly constant and distinct value for the two species (23.3±4.2 and −5.1±1.8‰ for P. fluorescens and P. denitrificans, respectively). The site preference was also measured for N₂O produced by inorganic reactions (nitrite reduction and hydroxylamine oxidation); a unique value (about 30‰ for the both reactions) was obtained. These results and those recently reported for nitrifying bacteria suggest that ¹⁵N-site preference in N₂O can be used to identify the production processes of N₂O on the level of bacterial species or enzymes involved.  相似文献   

A case study of improving milking cow performance and milking system performance with using a flow simulator     

Masafumi Enokidani  Kazuhiro Kawai  Yasunori Shinozuka  Tomomi Kurumisawa 《Animal Science Journal》2020,91(1)

Efforts to improve dairy performance have been focused on increasing milk productivity of cows through improved feeding systems and genetic potential. However, methods for evaluating milking system performance based on milk productivity have not yet been established. Milking system performance was evaluated by measuring the claw vacuum at five flow rates (1.9–8.7 kg/min) produced using a flow simulator for a single eight‐swing milking parlor with a high‐line system. Based on these results, a double eight‐parallel milking parlor with a low‐line system was installed and tested. Farmers can take data obtained from evaluations of milking system performance into account for future management decisions, such as renewing the milking system. By renewing the milking system, average milking productivity, somatic cell linear score (LS) of bulk milk, and LS of each cow were significantly improved in the year after installing the new system (p < .01). In addition to checking conventional milking systems, this novel diagnostic method using a flow simulator can be used for checking new installations and also for proposing renovations.  相似文献   

Insulin responses to administrations of amino acids and fatty acids in healthy cats     

Yasuda K  Takashima S  Takagi M  Nishii N  Ohba Y  Kitagawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(10):1281-1286

In order to compare the stimulation ability of insulin secretion, we determined changes in plasma glucose and insulin concentrations after intravenous administration of various amino acids and essential fatty acids in clinically healthy adult cats. Plasma glucose concentrations were within the normal ranges after injection of amino acids and fatty acids. Plasma insulin concentrations increased rapidly 2 to 4 min after injection of arginine, then decreased to the basal levels at 20 min in all five cats. Insulin peak responses were significantly greater in arginine injections than in normal saline (P<0.01). Areas under the curve (AUC) of plasma insulin concentrations from 0 to 10 min after injection of arginine were significantly larger than after injection of normal saline (P<0.01) and glucose (P<0.05). Increases in AUC of plasma insulin concentration from 0 to 60 min were observed after injection of arginine, leucine, alanine, and fat emulsion. Arginine had a strong insulinotropic effect, and leucine, alanine, and fatty acids had weak ones. Besides, valine, methionine, taurine and glutamine had no stimulant activity of insulin. Given the risk of glucose toxication and required time for testing, the intravenous arginine tolerance test may be useful for estimation of insulin responses in cats.  相似文献   

Serum osteocalcin in dairy cows: age-related changes and periparturient variation     

Sato R  Onda K  Ochiai H  Iriki T  Yamazaki Y  Wada Y 《Research in veterinary science》2011,91(2):196-198

We evaluated age-related changes in serum osteocalcin concentrations in non-periparturient cows and variations in serum osteocalcin concentration in periparturient primiparous and multiparous cows. The serum osteocalcin levels were evaluated in 144 non-periparturient Holstein dairy cows aged 11 days to 10 years; these levels were the highest in the youngest cows, appeared to steadily decrease with age until the time of the first calving, and were subsequently maintained at low levels. Between 14 days before calving and 21 days after calving, the serum osteocalcin levels were significantly higher in the primiparous cows than in the multiparous cows. A comparison between age-matched non-periparturient and periparturient cows showed that serum osteocalcin levels were significantly lowered during late gestation in both primiparous and multiparous cows. These results suggest that serum osteocalcin measurement might be useful for the detection of mineral imbalances at the time of parturition in cows.  相似文献   

Accumulation of calcium,magnesium, potassium and sodium with growth of individual leaves,petioles and stems of cucumber plants     

Makoto Iwahashi  Yasunori Tachibana  Yasusada Ohta 《Soil Science and Plant Nutrition》2013,59(4):441-449

Abstract

Accumulation of Ca, Mg, K and Na in each individual leaf, petiole and stem of the cucumber plant (Cucumis sativus L. cv. Kasairaku) was investigated in relation to the growth of these organs under water culture condition. Growth of each individual organ followed a sigmoidal curve showing two distinctive phases, the exponential and stationary phases. Accumulation patterns of these major cations showed a elose relationship with the growth characteristics of the organs.

1) Leaf Although the rate of accumulation of the cations declined during the stationary phase of growth, both Ca and Na accumulated in all the leaves throughout the whole period of growth. A higher Ca content was observed in the older leaves while the younger leaves showed a higher Na content. Mg and K accumulated during the exponential phase, whereas no appreciable accumulation was observed during the stationary phase.

2) Petiole and stem. Accumulation of Ca, Mg and Na continued throughout the whole period of growth. No deeline in the rate of accumulation of these cations was observed during the stationary phase unlike in the leaf, whereas K accumulation was observed only during the exponential phase of growth, as in the leaf.

All three organs showed that the content of these cations in each individual organ decreased during the exponential phase of growth. The rate of decrease was greater in younger organs than in older ones.  相似文献   

Preparation of heavy meromyosin from the autolyzed squid mantle muscle homogenate     

Takeya?Yoshioka  Yasunori?Kinoshita  Sanae?Kato  Young?-Je?Cho  Kunihiko?KonnoEmail author 《Fisheries Science》2005,71(1):213-219

ABSTRACT:   Incubation of squid mantle muscle homogenate caused a selective cleavage of myosin into heavy meromyosin (HMM) and light meromyosin (LMM). HMM was isolated from the incubated homogenate by using ammonium sulfate fractionation. The purified HMM retained two types of light chain components. Its Mg²⁺-ATPase activity with or without F-actin showed a Ca-sensitivity. HMM was cleaved into subfragment-1 and subfragment-2 upon chymotryptic digestion with or without Ca²⁺, possessing different light chain composition. Two types of light chain component were kept intact when digested in the presence of Ca²⁺. Ca²⁺ stabilized HMM especially in a bound form to F-actin.  相似文献   

Stress-induced apoptosis in larval embryos of Japanese flounder   总被引：1，自引：0，他引：1  

Takeshi  YABU  Yasunori  ISHIBASHI  Michiaki  YAMASHITA 《Fisheries Science》2003,69(6):1218-1223

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Effects of night‐time light intensity on the survival rate and stress responses in juvenile Pacific bluefin tuna Thunnus orientalis (Temminck and Schlegel)     

Tomoki Honryo  Michio Kurata  Tokihiko Okada  Yasunori Ishibashi 《Aquaculture Research》2013,44(7):1058-1065

Land‐based cultured juvenile Pacific bluefin tuna Thunnus orientalis (PBT) have high mortality rates due to collisions or contacts with tank walls after about 30 days of hatching. To determine the effect of night‐time lighting on their survival, juvenile PBT were reared under four different night‐time light intensities (0, 5, 15 and 150 lx) for 9 days, followed by a 3‐day observation period. High‐intensity, night‐time lighting (150 lx) significantly improved the survival rate (75.8%; P < 0.001) compared with the unlit control group (0 lx, 64.3%). The survival rate in the high‐intensity group decreased after the end of the lighting period. Lighting did not influence whole‐body cortisol levels, glucose levels, or diel changes in plasma cortisol levels. In contrast, the survival rates of fish exposed to light intensities between 5 and 15 lx were slightly lower than that of the unlit control group. These results suggest that providing night‐time lighting of 150 lx or higher is an effective method for reducing the mortality of cultured PBT.  相似文献