A comparative histological study on the distribution of striated and smooth muscles and glands in the esophagus of wild birds and mammals     

Shiina T  Shimizu Y  Izumi N  Suzuki Y  Asano M  Atoji Y  Nikami H  Takewaki T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(1):115-117

Musculature and glands of the esophagus in various wild birds and mammals were examined histologically. Cervical and thoracic esophagi of all birds used (mallard, spot-billed duck, Ural owl and Hodgson's hawk-eagle) were comprised of smooth muscle fibers only. In contrast, esophagi of the nutria, Japanese raccoon dog, common raccoon and Japanese marten consisted largely of striated muscle fibers. In the masked palm civet, Japanese macaque and bottlenose dolphin, esophageal muscle layers consisted of both striated and smooth muscle fibers. Esophageal glands were observed except for the nutria and masked palm civet. These results show a wide variety of the structural composition in the esophagus of wild animals, particularly mammals, examined in this study.  相似文献   

Insulin resistance: Relationship between indices during late gestation in dairy cows and effects on newborn metabolism     

Rui Hasegawa  Izumi Iwase  Tomohiro Takagi  Moeri Kondo  Motozumi Matsui  Chiho Kawashima 《Animal Science Journal》2019,90(12):1544-1555

To investigate the relationship between insulin resistance indices [“Revised quantitative insulin sensitivity check index” (RQUICKI; RQ), “Revised quantitative insulin sensitivity check index ‐ β‐hydroxybutyrate” (RQUICKI_BHB; RQ_BHB), and “Homeostasis model assessment‐insulin resistance” (HOMA‐IR; HR)], and metabolic parameters in dams during late gestation, and their newborn calves. Blood was sampled twice weekly during the experimental period in 30 dry Holstein cows. In calves, blood sampling and body weight measurements were performed immediately after birth, and in 1‐week‐old male calves, liver and muscle biopsy samples were obtained for determining metabolic factor mRNA levels. RQ and RQ_BHB were negatively correlated with insulin, nonesterified fatty acid, BHB, and albumin and were positively correlated with leptin levels in blood during late gestation (p < .05). RQ, rather than RQ_BHB, reflected metabolism of dams, while stronger positive correlations were present between HR and blood insulin concentrations than other parameters, and calves of dams with high HR had low body weight, and high liver and muscle expression of growth hormone and insulin receptor mRNA (p < .05). RQ and HR of dams during late gestation could serve as indicators of dam metabolism and predictors of metabolism in newborn calves respectively.  相似文献   

The sensitivity of dragonflies to landscape structure differs between life-history groups     

Taku Kadoya  Shin-ichi Suda  Yoshitaka Tsubaki  Izumi Washitani 《Landscape Ecology》2008,23(2):149-158

Contrasting life-history strategies of long versus short pre-reproductive phases are known in adult dragonflies (Odonata) of temperate regions. Because the long-phase species spend a longer time in terrestrial habitats such as grasslands or woodlands during their pre-reproductive phase, we hypothesized that long-phase species would be more sensitive to landscape structure than short-phase species. To test this hypothesis, we conducted periodic censuses of adult dragonflies at small man-made ponds. We compared the two above functional groups in terms of the degree to which species occurrence depended on landscape structure. The difference among the two groups was not significant, but occurrence of long-phase species tended to depend on landscape structure. Long-phase species responded to landscape structure at larger spatial scales and showed stronger spatial autocorrelation in their occurrence among sampling ponds than short-phase species.  相似文献   

Water supply from pearl millet by hydraulic lift can mitigate drought stress and improve productivity of rice by the close mixed planting     

Yasuhiro Izumi  Shinji Okaichi  Simon K. Awala  Yoshimasa Kawato  Yoshinori Watanabe  Koji Yamane 《Plant Production Science》2018,21(1):8-15

The authors have proposed the close mixed planting technique using mixed seedlings of two different crop species that results in close tangling of their root systems. Especially, the combination of drought-adaptive upland crops (e.g. pearl millet or sorghum) and flood-adaptive lowland crop of rice would be beneficial to overcome the drought and flood conditions and to reduce the risks of crop failure. In our previous studies, we found that upland crop yield losses by flood stress was mitigated by mix-cropped rice, owing to the oxygen gas released from the rice roots into the aqueous rhizosphere. In the present study, we conducted two experiments to assess whether mixed cropping a drought-resistant cereal, pearl millet, would improve the performance of co-growing drought-susceptible crop, rice under drought conditions. In the field experiment, some grains were obtained from the rice plants mix-cropped with pearl millet under drought condition. However, no rice matured in the single cropping system. In the model experiment using deuterium analysis, it was confirmed that water absorbed by pearl millet roots from deep soil layer was utilized by rice, suggesting that mix-cropped rice could withstand drought stress and complete grain filling using water released into the upper soil layer by hydraulic lift.  相似文献   

Interactions of picrodendrins and related terpenoids with ionotropic GABA receptors of mammals and insects     

Yoshihisa Ozoe  Miki Akamatsu  Taizo Higata  Izumi Ikeda  Kazuo Mochida  Kazuo Koike  Taichi Ohmoto  Tamotsu Nikaido 《Pest management science》1999,55(6):665-666

Different structural features govern the interaction of picrodendrins and related terpenoids with rat and with housefly GABA receptors. This supports previous studies which suggest that there are significant differences between the structures of the binding sites in these two receptors.  相似文献   

Evidence of nighttime movement of finless porpoises through Kanmon Strait monitored using a stationary acoustic recording device     

Tomonari Akamatsu  Izumi Nakazawa  Takashi Tsuchiyama  Naoko Kimura 《Fisheries Science》2008,74(5):970-975

From March 2005 to March 2006, the presence of the finless porpoise Neophocaena phocaenoides in the Kanmon Strait, Japan was monitored using a stationary acoustic event recording device. A stereo acoustic event recorder (A-tag) recorded biosonar signals as well as sound source directions, which can be used to count the number of echolocating porpoises within a distance of 126m. During 75 days of effective observation, 37 porpoises were detected acoustically. On average, one individual was detected every two days. Most of the finless porpoises appeared at night, and no porpoises were observed from 12:00 to 18:00 hours. Shipping traffic observed using the same acoustic system showed trends opposite to that of finless porpoise during the daytime. The tidal current did not affect the presence of the animals. (up to 5.2 knots). However, porpoises were suggested to swim along the current direction. Finless porpoise appeared to be isolated and used relatively long-range sonar during the observations, suggesting that the porpoises passed through the Kanmon Strait rather than searched for prey.  相似文献   

Identification and detection of Pseudomonas plecoglossicida isolates with PCR primers targeting the gyrB region   总被引：1，自引：0，他引：1  

Izumi S  Yamamoto M  Suzuki K  Shimizu A  Aranishi F 《Journal of fish diseases》2007,30(7):391-397

Pseudomonas plecoglossicida is the agent of bacterial haemorrhagic ascites (BHA) in freshwater fish farming in Japan. To develop a rapid identification and detection method for P. plecoglossicida, a PCR amplification technique targeting the chromosomal DNA region coding the B subunit of the DNA gyrase (gyrB) was used. The nucleotide sequences of gyrB were determined in nine isolates of P. plecoglossicida and two other Pseudomonas species. On the basis of these determined sequences and the gyrB sequences of other Pseudomonas species or fish pathogenic bacteria deposited in international nucleotide sequence databases (GenBank/EMBL/DDBJ), PCR primers PL-G1F, PL-G1R, PL-G2F and PL-G2R were designed for specific amplification of the partial gyrB of P. plecoglossicida. The specificity of these primers in amplifying the gyrB of P. plecoglossicida was verified using selected strains of related bacterial species. The nested PCR technique was used to detect P. plecoglossicida from kidney and intestine of ayu. Primer pair PL-G1F and PL-G1R was used for the external PCR, and primer pair PL-G2F and PL-G2R for the internal PCR. Of 10 ayu juveniles, expected size PCR products were observed from intestine and kidney samples in one and two specimens, respectively. The PCR technique with primers based on the gyrB sequence is thus useful for the diagnosis of BHA.  相似文献   

Synthesis and structure–activity relationship analysis of bicyclophosphorothionate blockers with selectivity for housefly γ‐aminobutyric acid receptor channels     

Xiu‐Lian Ju  Sayaka Fusazaki  Hiroyuki Hishinuma  Xiaomu Qiao  Izumi Ikeda  Yoshihisa Ozoe 《Pest management science》2010,66(9):1002-1010

BACKGROUND: Bicyclophosphorothionates (2,6,7‐trioxa‐1‐phosphabicyclo[2.2.2]octane‐1‐sulfides) are blockers (or non‐competitive antagonists) of γ‐aminobutyric acid (GABA) receptor channels. Twenty‐two bicyclophosphorothionates with different 3‐ and 4‐substituents were synthesised, and [³H]4′‐ethynyl‐4‐n‐propylbicycloorthobenzoate (EBOB) binding assays were performed to evaluate their affinities for housefly and rat GABA receptors. RESULTS: Introduction of an isopropyl group at the 3‐position enhanced the affinity of bicyclophosphorothionates for housefly GABA receptors and reduced the affinity towards rat GABA receptors. The 4‐isopentyl‐3‐isopropylbicyclophosphorothionate showed the highest affinity for housefly GABA receptors (IC₅₀ = 103 nM ) among the analogues tested, while the 4‐cyclohexylbicyclophosphorothionate showed the highest affinity for rat GABA receptors (IC₅₀ = 125 nM ). Among the bicyclophosphorothionates synthesised to date, the former analogue exhibited the highest selectivity for housefly GABA receptors, with an IC₅₀^rat/IC₅₀^fly ratio of approximately 97. Three‐dimensional GABA receptor models successfully explained the structure–activity relationships of the bicyclophosphorothionates. CONCLUSION: The results indicate that minor structural modifications of blockers can change their selectivity for insect versus mammalian GABA receptors. The substituent at the 3‐position of the bicyclophosphorothionates dictates selectivity for housefly versus rat GABA receptors. This information should prove useful for the design of safer insecticides and parasiticides. Copyright © 2010 Society of Chemical Industry  相似文献   

Alleviative effects of mixed-cropping with rice on the growth inhibition of pearl millet caused by flooding at reproductive stage     

Simon K. Awala  Koji Yamane  Yasuhiro Izumi  Osmund D. Mwandemele 《Journal of Crop Improvement》2019,33(1):42-52

Flooding has globally become common, and thus cultivation techniques to adapt to the stress are required. We have developed a technique called “close mixed-planting” using flood-adapted rice (Oryza sativa L.) and upland crops with tangled root systems, showing that this technique can mitigate the damage caused to upland crops by flooding. However, the plant response during the reproductive stage has not yet been examined. In this study, we estimated the alleviative effects of close mixed-planting on the growth inhibition and physiological damage to pearl millet (Pennisetum glaucum) caused by flooding at the reproductive stage in northern Namibia. Pearl millet and NERICA4 (Oryza spp., interspecies of O. sativa and O. glaberrima) were used. Four-week-old single- and mixed-crop pearl millets were transplanted and grown for 22 days, and then flooding treatment was administered for 28 days. The growth and physiological parameters of single pearl millet were significantly decreased by flooding stress, and the parameters did not recover during a 14-day recovery period compared with those of unflooded single and mix-cropped pearl millet. On the other hand, the damage to mix-cropped pearl millet by flooding was suppressed. Thus, the mixed-cropping mitigated the anoxic stress of pearl millet caused by flooding at the reproductive stage and contributed to the improved growth after the recovery period. This result suggested that the close mixed-planting with rice can contribute to the mitigation of flooding damage not only at the vegetative stage but also at the reproductive stage of pearl millet in the semi-arid African country, Namibia.  相似文献   

Genetic analysis of host–pathogen incompatibility between Lolium isolates of Pyricularia oryzae and wheat     

Trinh Thi Phuong Vy  Gang-Su Hyon  Nguyen Thi Thanh Nga  Yoshihiro Inoue  Izumi Chuma  Yukio Tosa 《Journal of General Plant Pathology》2014,80(1):59-65

Lolium isolate TP2 of Pyricularia oryzae, causal agent of gray leaf spot of perennial ryegrass (Lolium perenne), is virulent on perennial ryegrass, but avirulent on wheat cultivars. Genetic analysis of wheat F₂ populations revealed that the resistance of wheat cultivars Chinese Spring, Shin-chunaga, and Norin 4 to TP2 was conditioned by two genes, R1 and R2. R1 was highly effective, while R2 was less effective. The strong resistance gene R1, designated Rmg6, was mapped on chromosome 1D using microsatellite markers. For revealing genetic mechanisms of avirulence, TP2 was crossed with Triticum isolate Br48. Segregation analysis of their F₁ progenies revealed that the avirulence of TP2 on the three wheat cultivars was conditioned by two unlinked genes, one (A1) highly effective and the other (A2) less effective. These results suggest that the incompatibility between TP2 and the common wheat cultivars is conditioned by two gene pairs; the Rmg6–A1 interaction results in strong resistance, and the R2–A2 interaction results in moderate resistance.  相似文献