Assessment of longitudinal tissue Doppler imaging of the left ventricular septum and free wall as an indicator of left ventricular systolic function in dogs     

Hori Y  Sato S  Hoshi F  Higuchi S 《American journal of veterinary research》2007,68(10):1051-1057

OBJECTIVE: To evaluate tissue Doppler imaging (TDI) of the left ventricular (LV) free wall (FW) and ventricular septum (VS) as an indicator of LV systolic function in dogs. ANIMALS: 7 healthy Beagles. PROCEDURES: Doses of dobutamine (5 and 10 microg/kg/min) and esmolol (50 and 100 microg/kg/min) were infused into the LV of each dog. With each dose, heart rate; myocardial performance index (MPI); transmitral inflow and ejection time (determined via pulsed-wave Doppler [PWD] echocardiography); and FW and VS velocities of the mitral valve annulus (determined via TDI during systole [S'], early diastole [E'], and late diastole [A']) were assessed. RESULTS: With each dose, dobutamine significantly increased heart rate and the first derivatives of LV pressure (+dP/dt and -dP/dt), whereas esmolol significantly decreased the +dP/dt and -dP/dt values, compared with baseline. Esmolol (100 microg/kg/min) significantly decreased the VS-TDI-derived S' velocity and FW-TDI-derived E' velocity; dobutamine significantly increased transmitral inflow and TDI velocities. Regression coefficient between VS-TDI-derived S' velocity and +dP/dt was higher than that between FW-TDI-derived S' velocity and +dP/dt. Compared with baseline, the PWD- and VS-TDI-derived MPI were significantly decreased by dobutamine and significantly increased by esmolol at each dose. Values of FW-TDI-derived MPI were higher than values derived via the other techniques. Correlation between +dP/dt and VS-TDI-derived MPI was greater than that between +dP/dt and FW-TDI- or PWD-derived MPI. CONCLUSIONS AND CLINICAL RELEVANCE: In healthy dogs, the VS-TDI-derived S' velocity and MPI appear to be reliable assessments for evaluating LV systolic function.  相似文献   

Stock structure and resource management of hairtail <Emphasis Type="Italic">Trichiurus japonicus</Emphasis> based on seasonal broods around the Bungo Channel,Japan     

Shingo Watari  Syunji Tokumitsu  Taro Hirose  Michio Ogawa  Mitsutaku Makino 《Fisheries Science》2017,83(6):865-878

Declines in landings of the hairtail Trichiurus japonicas indicate the need for more effective management of this species. Hairtail spawning peaks occur twice yearly in the Bungo Channel, in spring and autumn. Relationships between hairtail stock and brood seasonality were examined to determine if an association between either and a decline in landings existed. Stock assessments show that the biomass of both spring and autumn hairtail broods from within and around the Bungo Channel are decreasing, with a rapid reduction in spring-brood stock abundance after 2007 largely responsible for decreased landings. Yield and spawning per recruitment analyses indicate current fishing pressure to be higher than several reference points. We suggest that fishing pressure needs to be reduced by at least 20% of the current level for this fishery to remain sustainable, as the projected stock abundance and catch demonstrate that the current fishing pressure is unsustainable. Analysis of time-series data of recruits per spawning revealed spring-brood recruitment to have been strong in year classes 2003 and 2005. Of various options available for improved management of this fishery, we propose that fishing pressure should be reduced in the years following the appearance of strong year classes to increase future biomasses and landings.  相似文献   

Genetic identification and morphology of naturally spawned eggs of the Japanese eel Anguilla japonica collected in the western North Pacific     

Tatsuki Yoshinaga  Michael J. Miller  Kazuki Yokouchi  Tsuguo Otake  Shingo Kimura  Jun Aoyama  Shun Watanabe  Akira Shinoda  Machiko Oya  Sachie Miyazaki  Kei Zenimoto  Ryusuke Sudo  Tetsuya Takahashi  Hyojin Ahn  Ryotaro Manabe  Seishi Hagihara  Hiroshi Morioka  Hikaru Itakura  Masamichi Machida  Kazuyuki Ban  Mayu Shiozaki  Bunpei Ai  Katsumi Tsukamoto 《Fisheries Science》2011,77(6):983-992

Eggs of the Japanese eel Anguilla japonica collected in the western North Pacific were identified by onboard species-specific polymerase chain reaction (PCR) and DNA nucleotide sequencing after the cruise. Fish eggs of various species were collected by large plankton net tows at 12 stations along the southern part of the West Mariana Ridge on 19–25 May 2009. A total of 43 fish eggs were distinguished morphologically as possibly being of A. japonica. Thirty-one of those were analyzed by PCR, which included 15 eggs collected at 12°50–55′N, 141°15–20′E (in 5 tows) that showed positive results. The 16S ribosomal RNA (rRNA) gene sequences of eggs determined after the cruise indicated that 31 A. japonica eggs had been collected. The remaining eggs were of mesopelagic eel species (Serrivomeridae and Derichthyidae), or unidentified species. The morphological characteristics of the A. japonica eggs were consistent with those of artificially spawned eggs, except they had a slightly larger diameter. The egg diameter range did not overlap with those of mesopelagic eels of the Serrivomeridae, which often spawn in the same area as A. japonica. These results suggest that egg diameter and embryo shape can be used to morphologically identify naturally spawned A. japonica eggs.  相似文献   

Vortex flow produced by schooling behavior of arabesque greenling <Emphasis Type="Italic">Pleurogrammus azonus</Emphasis>     

Takashi Kitagawa  Takashi Nakagawa  Ryuji Kimura  Hiroshi Niino  Shingo Kimura 《Fisheries Science》2011,77(2):217-222

Arabesque greenling Pleurogrammus azonus form schools of 30,000–60,000 individuals to feed on mesozooplankton near the sea surface. The fish need to be close to the surface where mesozooplankton production occurs, but the food is not sufficiently dense there for the fish to grow optimally while avoiding predation by sea birds. Arabesque greenling use a unique method to optimize their feeding conditions while avoiding staying on the sea surface. When the school swims upward, water is pushed downward. Upward swimming of a school of 30,000 individuals generates a downward stream of about 0.8–1.1 m/s, resulting in a convergent flow near the surface. This convergence concentrates the mesozooplankton on the sea surface and transports them into deeper layers with a strong vortex about 3.0 m in diameter and 10–20 m long. Thus, schooling of this fish induces vortex flows that provide a rich feeding environment.  相似文献   

Estimating larval supply of Ezo abalone <Emphasis Type="Italic">Haliotis discus hannai</Emphasis> in a small bay using a coupled particle-tracking and hydrodynamic model: insights into the establishment of harvest refugia     

Yoichi Miyake  Shingo Kimura  Tomohiko Kawamura  Takashi Kitagawa  Motoyuki Hara  Hiroshi Hoshikawa 《Fisheries Science》2010,76(4):561-570

Most juveniles of Haliotis discus hannai have been found to be descendants of wild individuals, although most adults were artificially produced (released) individuals as a result of restocking inside the refugium located near the head of Oshoro Bay, Hokkaido, Japan. To estimate the larval supply from released and wild individuals into the refugium and to compare the suitability of locations as larval sources, we simulated larval dispersal using a coupled hydrodynamic and particle-tracking model. The simulation results indicated that more larvae may be supplied from the wild adults inside the bay to the refugium than from the released adults. These results are consistent with the observed high abundance of wild juveniles in the refugium. Most larvae from the refugium were predicted to disperse out of the bay. We found that larval retention in the bay was at least one order of magnitude higher than that in the refugium. Thus, it may be more effective in terms of self-replenishment and reproduction if the refugium were to be expanded to the bay scale. There were only minor differences among the compared sites at the head of the bay in terms of their suitability as larval sources. Consequently, the establishment of new refugia in this area could be expected to provide an effectiveness equal to that of the current refugium.  相似文献   

Myricanol and myricanone biosynthesis in <Emphasis Type="Italic">Myrica rubra</Emphasis>: incorporation of two molecules of 4-coumaric acid     

Shingo Kawai  Kyousuke Nakata  Masako Ohashi  Tomoaki Nishida 《Journal of Wood Science》2008,54(3):256-260

After feeding experiments of Myrica rubra young shoots with 4-[8,9-¹³C₂]coumaric acid, mass spectrometric analyses revealed that the cyclic diarylheptanoids, myricanol and myricanone, were derived from two molecules of 4-coumaric acid. ¹³C Nuclear magnetic resonance analysis of myricanol isolated after administration of 4-[8,9-¹³C₂]coumaric acid demonstrated that the C-8 and C-9 atoms of 4-coumaric acid are incorporated into C-8, C-9, C-11, and C-12 of the corresponding myricanol. Part of this report was presented at the 56th Annual Meeting of the Japan Wood Research Society, Akita, August 2006  相似文献   

Effect of wind stress on the catch of Japanese anchovy Engraulis japonicus off northwestern Kyushu, Japan     

Aigo Takeshige  Yoichi Miyake  Hideaki Nakata  Takashi Kitagawa  Shingo Kimura 《Fisheries Science》2013,79(6):989-998

Effect of wind stress on the annual catch of Japanese anchovy Engraulis japonicus off northwestern Kyushu for the period between 1963 and 2009 was investigated. Regime shift analysis detected several step changes in catch and environmental variables. Since the mid-1980s, the anchovy catch in the coastal fishery zones has declined, while the catch in the offshore zone has increased. The decline of catch in the coastal zones showed a significant correlation with the long-term variations in prevailing north-northeastward wind stress over the Goto-Nada Sea during spring spawning season. The results indicated that weakened north-northeastward winds caused the recent low recruitment of anchovy through low levels of wind-induced eggs and larval transport from the offshore spawning ground to the coastal nursery areas, resulting in the potential shift of nursery area to the northwestern offshore region. Thus, as well as the growth-favorable ambient temperature, transport process would play a key role on long-term fluctuations in anchovy abundance in these coastal seas.  相似文献   

Expression patterns of the slit subfamily mRNA in canine malignant mammary tumors     

Tanno T  Tanaka Y  Sugiura T  Akiyoshi H  Takenaka S  Kuwamura M  Yamate J  Ohashi F  Kubo K  Tsuyama S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(11):1173-1177

Slit, a secreted protein, functions as a chemorepellent factor in axon guidance and neuronal migration and as an inhibitor in leukocyte chemotaxis. In humans, slit2 protein attracts endothelial cells and promotes tube formation in the tumor angiogenic mechanism. In this study, we cloned a part of the canine slit subfamily and examined the expression of slit subfamily mRNAs in 3 normal canine mammary glands and 11 mammary tumor samples by RT-PCR. The cloned part of the slit gene sequences showed high similarity to those of the human, mouse, and rat. The mRNAs were expressed at low levels in the normal mammary gland. The expression levels of slit1 mRNA were low in both the normal and tumor tissues. In contrast, the expression of slit2 mRNA increased in most of the malignant mammary tumors, and an increase in slit3 mRNA expression was observed in 2 of the malignant mixed tumors. These results suggest that the expression of slit2 plays an important role in tumor angiogenesis in canine mammary gland tumors and that slit2 can be a putative marker for malignancy diagnosis of these tumors.  相似文献   

Proliferation of equine bone marrow-derived mesenchymal stem cells in gelatin/β-tricalcium phosphate sponges     

Seo JP  Tsuzuki N  Haneda S  Yamada K  Furuoka H  Tabata Y  Sasaki N 《Research in veterinary science》2012,93(3):1481-1486

A three dimensional scaffold is essential in mesenchymal stem cells (MSCs) delivery in cell-based therapy for facilitating cell adherence, migration, proliferation, and differentiation. The objectives of this study were to evaluate the possibility of β-tricalcium phosphate incorporated gelatin sponges (Gelatin/β-TCP sponge) as scaffolds for equine MSCs and to examine the effects of seeding density and seeding method on the proliferation of equine MSCs in the Gelatin/β-TCP sponges. Mononuclear cells and MSCs isolated from bone marrow were seeded into Gelatin/β-TCP sponges at different densities by different seeding methods-static or agitated methods. Proliferation of the MSCs in Gelatin/β-TCP was assessed using the Cell Counting Kit-8 assay and histological examination. Distribution and proliferation of MSCs in the Gelatin/β-TCP sponge were observed, and the Gelatin/β-TCP sponge supported limited growth when seeded at high density. We also found that the agitated seeding method enhanced the proliferation of MSCs. This study demonstrated the suitability of Gelatin/β-TCP sponges for the proliferation and maintenance of equine MSCs. These results contribute to the application of MSC-seeded Gelatin/β-TCP sponges in equine medicine.  相似文献   

Seroepidemiological survey of sheep flocks from Northern Japan for Mycoplasma ovipneumoniae and Mycoplasma agalactiae     

Giangaspero M  Nicholas RA  Hlusek M  Bonfini B  Osawa T  Orusa R  Tatami S  Takagi E  Moriya H  Okura N  Kato K  Kimura A  Harasawa R  Ayling RD 《Tropical animal health and production》2012,44(3):395-398

Sheep flocks from Hokkaido, Iwate and Aomori, three northern prefectures of Japan, were screened for antibodies to Mycoplasma ovipneumoniae and Mycoplasma agalactiae by ELISA. Sixty four animals out of 246 (26%) were seropositive to M. ovipneumoniae, with positive results obtained from all three prefectures. None of the sera tested were serologically positive to M. agalactiae.  相似文献