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201.
Cloning of kuruma prawn Marsupenaeus japonicus crustin-like peptide cDNA and analysis of its expression 总被引:1,自引:0,他引:1
Achara RATTANACHAI Ikuo HIRONO Tsuyoshi OHIRA Yukinori TAKAHASHI Takashi AOKI 《Fisheries Science》2004,70(5):765-771
ABSTRACT: Antimicrobial peptides serve as an important component of the innate immune system of all species by functioning to provide a rapid first line defense against infection. Arthropod antimicrobial peptides have been well described in insects, whereas only a few molecules have been identified in crustaceans. Five variants (types 1–5) of Marsupenaeus japonicus crustin-like peptide cDNA that were obtained from a hemocyte cDNA library and polymerase chain reaction (PCR) amplification are reported here. Marsupenaeus japonicus crustin-like peptide type 1, the predominant type, has a cDNA consisting of 679 nucleotides and an open reading frame consisting of 573 base pairs coding for 191 amino acid residues. Other types contain varying glycine-rich repeats at the N-terminal amino acid sequences. The deduced amino acid sequences of these variants are highly similar to those of Litopenaeus setiferus (80% identity), Litopenaeus vannamei (80% identity) and Carcinus maenas crustins (44% identity). Expression of Marsupenaeus japonicus crustin-like peptide mRNA was detected in hemocytes, but not in the heart, hepatopancreas, gill, fore-gut, mid-gut, muscle, subcuticular epithelium or ovary. The expression level of crustin-like peptide mRNA increased significantly 1, 3 and 7 days post-peptidoglycan feeding as determined by quantitative real-time PCR. These results suggest that crustin-like peptide could have an important role in shrimp defense mechanisms. 相似文献
202.
203.
Ikuo?YoshinagaEmail author Yanwen?Feng Ram?Karan?Singh Eisaku?Shiratani 《Paddy and Water Environment》2004,2(3):145-152
Based on an experimental field study in Japan, a model was developed to simulate dissolved nitrogen in water ponded in a paddy field. As input data, the model uses meteorological data, water balance in the field, nitrogen concentration in inlet water, and the nitrogen contribution of applied fertilizer. Five model parameters need calibration. A practical application of the model is the simulation of NH4-N and NO2+3-N concentrations in water ponded in a paddy field. The model improves our understanding of the interactions between forms of dissolved nitrogen in ponded water and can explain the complex changes in dissolved nitrogen concentrations in water ponded on a paddy field. 相似文献
204.
Daigo Takemoto Yusuke Shibata Makoto Ojika Yuri Mizuno Sayaka Imano Mina Ohtsu Ikuo Sato Sotaro Chiba Kazuhito Kawakita Soriya Rin Maurizio Camagna 《Journal of General Plant Pathology》2018,84(5):312-320
The oomycete Phytophthora infestans is the causal agent of potato late blight, one of the most destructive and historically significant pathogens in agricultural production. A virus-induced gene silencing-based screening of the solanaceous model plant N. benthamiana resulted in revealing a wide range of resistance mechanisms of solanaceous plants against this pathogen. In this article, we present an overview of the various pathways involved in the N. benthamiana–P. infestans pathosystem, including some of the follow-up work that was triggered by these findings. The purpose of this review is to assemble these findings and integrate them into our current understanding of plant pathogen defense mechanisms and discuss their potential application for the development of potato resistance to P. infestans. 相似文献
205.
Nishimori T Ishihara R Kanno T Jayawardane GL Nishimori K Uchida I Imai K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(10):1171-1176
Transmission of ovine herpesvirus-2 (OvHV-2) in sheep via natural contact and nasal secretions was examined. OvHV-2-free lambs were produced by separating newborn lambs from their mothers within 5 days of birth and raising them in an isolation facility. Transmission experiments via natural contact were conducted by keeping OvHV-2-free lambs with OvHV-2-infected sheep of different ages. Six of the infected ewes in this experiment were pregnant and gave birth during the experimental period. OvHV-2 was not transmitted from the adult sheep, though viral DNA was consistently detected in their peripheral blood leukocytes (PBL). On the other hand, OvHV-2 was transmitted from recently infected lambs to sheep at 10 or 12 weeks after the onset of contact. In addition, we attempted the experimental transmission of OvHV-2 via nasal secretions, by transferring nasal washings from infected sheep to the nostrils of uninfected sheep. Sheep receiving the nasal washings from infected adult sheep maintained their negative status for 15 months, whereas sheep receiving nasal washings from recently infected lambs acquired OvHV-2 by 8 months. The results of these experiments support that OvHV-2 is more easily transmitted to negative sheep by recently infected lambs than by adult sheep. Further, it is supposed that the nasal cavity is a portal for entry and shedding of infectious OvHV-2 in sheep. 相似文献
206.
Toshihiro Nade Yuya Kataoka Kazuhiro Hoshi Ikuo Maeda Kunihiko Saito 《Animal Science Journal》2014,85(3):247-253
This study investigated an objective method for estimating beef marbling using ultrasonic images of the Iliocostalis muscle and the Lomgissimus muscle area sections. Thirty‐one Japanese Black cattle steers were used in this study. The end of the left side shoulder blade bone was scanned using an ultrasonic device. Ultrasonic images were captured of the Longissimus muscle area and that around the Iliocostalis muscle area. Twenty items were measured in the two images using computer image analysis software. The level of beef marbling was measured according to the Beef Marbling Standard (BMS) for carcass grading, and the percentage of ether‐extractable fat content in the Longissimus muscle (EE). The difference in the gray level between the Iliocostalis muscle and intermuscular fat (X10) was used to estimate the BMS and the EE, which were highly correlated (r2 = 67.72% and 61.30%). An equation was developed using four parameters from the two ultrasonic images, which could estimate the BMS (r2 = 85.88%). This equation could also estimate the EE (r2 = 68.98%). The equations used to estimate beef marbling were based on one to four parameters that included X10. Thus, ultrasonic images of the Iliocostalis muscle area section are important for estimating beef marbling. 相似文献
207.
Hossam EL-SHEIKH ALI Go KITAHARA Youji TAMURA Ikuo KOBAYASHI Koichiro HEMMI Shidow TORISU Hiroshi SAMESHIMA Yoichiro HORII Samy ZAABEL Shunichi KAMIMURA 《The Journal of reproduction and development》2013,59(1):59-65
The aim of the present study was to describe the temperature of the different portions
of the female genital tract and their relation to rectal temperature and to investigate
the effect of steroid hormones profiles on these variables over the estrous cycle in
cattle. Four nonpregnant Japanese Black cows were investigated daily over two successive
estrous cycles using a digital thermometer with a long probe and rounded-end sensor to
record the temperature of the rectum (RT), vagina (VT), cervix (CT), uterine body (UBT)
and uterine horns (UHT). Blood samples were collected immediately before temperature
recording to assay peripheral levels of progesterone (P4) and estradiol-17β
(E2). Moreover, transrectal ultrasonography was carried out after temperature
recording to monitor the ovulatory follicle and track ovulation. During the experiment,
the ambient temperature and relative humidity were recorded for further calculation of the
temperature humidity index (THI). The temperature within the genital tracts in these cows
progressively increased towards the uterine horns from the vagina. The VT, CT, UBT and
UHTs were significantly higher in association with peripheral P4 concentrations
greater than 4 ng/ml (mid-luteal phase) when compared with lower peripheral P4
concentrations. The VT was more significantly (P<0.01) correlated to the CT, UBT and
UHTs than RT. In conclusion, a temperature gradient was present among the vagina, cervix
and uterus over the estrous cycle, and changes in peripheral P4 concentrations
were associated with the thermal variations within these portions. The VT could be more
beneficial than RT in monitoring temperature of deeper portions of the female genital
tract in bovine. 相似文献
208.
Toshihiro Wada Kyoichi Kamiyama Shinya Shimamura Ikuo Matsumoto Takuji Mizuno Yoshiharu Nemoto 《Fisheries Science》2011,77(5):785-793
Habitat utilization, feeding, and growth of a rare pleuronectid flatfish, spotted halibut Verasper variegatus, were examined in a brackish lagoon in northeastern Japan: Matsukawa-ura. The distribution and date–length data of spotted
halibut collected mainly from beam-trawl samplings during 1983–2008 indicated that age-0 juveniles [n = 25, 6.0–18.0 cm total length (TL)] and older spotted halibut (n = 71, 13.8–43.0 cm TL) inhabited almost the entire northern part of Matsukawa-ura. Comparative distribution surveys of spotted
halibut, stone flounder, and marbled flounder during 1985–1989 revealed similar distribution patterns of these flatfishes;
the highest densities were found around the central part of Matsukawa-ura, although significantly lower abundance was detected
for spotted halibut. Linear growth equations of age-0 juveniles demonstrated that spotted halibut were able to achieve high
growth after June, probably because abundant prey (e.g., mysids and gammarids) and suitable physical conditions (warmer water
temperature and lower salinity) were present. The main prey items shifted from various crustaceans including mysids, caridean
shrimps, and anomurans to brachyura Hemigrapsus spp. (≥20 cm TL). Our study shows that spotted halibut use the shallow brackish lagoon as an important nursery for juveniles,
and also as a feeding ground for young and adults. 相似文献
209.
Bhuwan Rai Hiroko Takahashi Kenji Kato Yo-ichiro Sato Ikuo Nakamura 《Genetic Resources and Crop Evolution》2012,59(8):1713-1726
PolA1, a single-copy nuclear gene encoding the largest subunit of RNA polymerase I, comprises highly polymorphic intron 19 and nucleotide tag (Ntag) sequences. We analyzed these sequences in 42 accessions, which differed in ploidy, of Triticum–Aegilops and Hordeum species. The lengths of the intron 19 sequences were ca. 110?bp long in Triticum–Aegilops species, except in four Sitopsis species, Ae. longissima, Ae. searsii, Ae. sharonensis, Ae. speltoides, which had introns similar in length to those of Hordeum species, i.e., ca. 240?bp long. Phylogenetic analyses of the Ntag sequences showed that the four Sitopsis and remaining Triticum–Aegilops species were classified into two discrete Hordeum and Triticum clades, respectively. The A and D genome-specific Ntag sequences of polyploid wheats were highly homologous with those of T. urartu and Ae. tauschii, respectively. In Ae. bicornis, another Sitopsis species, two accessions had the short intron 19 and Triticum–type Ntag sequence, which were highly homologous with those of the B genome in polyploid wheats, whereas one accession contained the long intron 19 and Hordeum–type Ntag sequences. In contrast, partial sequence analyses revealed that the three accessions of Ae. bicornis shared highly homology to single-copy DMC1 and EF-G genes. The discrepancy between these results indicates that the Sitopsis species were probably established by hybrid speciation including ancient introgressive hybridization between progenitors of Triticum–Aegilops and Hordeum. Although many researchers have proposed Ae. speltoides as a candidate for the B genome donor, our data suggest the existence of diploid B genome species in the past that were responsible for the origin of both polyploid wheats and Sitopsis species, including Ae. speltoides. 相似文献
210.
Hiroaki?Naka Ikuo?Hirono Ken?Kurokawa Takashi?AokiEmail author 《Fisheries Science》2005,71(6):1209-1216
ABSTRACT: Random sequencing of the genomic DNA of Photobacterium damselae subsp. piscicida was conducted. The sequences were assembled into 930 contigs. The total length of these contigs accounts for 37.5% of the genome of P. damselae subsp. piscicida. The contigs contain 2055 open reading frames (ORFs) that have homology with genes in the GenBank database. Furthermore, some of the ORFs have homology with reported virulence related genes, and are classified as encoding colonization factors, exotoxin, and lipopolysaccharide (LPS). Thirty-seven ORFs have homology with colonization factors. In those colonization factors, 27, three, and four ORFs have homology with polar flagellar-related genes, capsule-related genes, and others (accessory colonization factors, superoxide dismutase (Cu-Zn), MshA biogenesis protein, and heme receptor genes), respectively. Five ORFs have homology with exotoxin-related genes (2 hemolysin, phospholipase, hyaluronidase, lysophospholipase L2 genes). Further, six ORFs have homology with LPS-related genes. 相似文献