Eradication of feral goats enhances expansion of the invasive shrub Leucaena leucocephala on Nakoudo‐jima,an oceanic island          下载免费PDF全文

T Osawa  K Hata  N Kachi 《Weed Research》2016,56(2):168-178

Many introduced species can co‐exist within the same ecosystem and sometimes interact with each other. Under such situations, eradication of one species may cause unexpected negative effects. Nakoudo‐jima in the Ogasawara (Bonin) Islands is an oceanic island that had feral goats that were introduced in the 1880s, but eradicated in 1999. Following their eradication, the alien invasive shrub Leucaena leucocephala (Fabaceae) was predicted to increase drastically. In this study, we tested the hypothesis that the eradication of feral goats enhanced the expansion of L. leucocephala using four time‐series aerial photographs and validation work based on current field surveys of Nakoudo‐jima. Our results showed that following feral goat elimination, bare ground areas decreased and forest cover increased. This was particularly true of areas dominated by L. leucocephala. Thus, feral goats appear to have limited the expansion of L. leucocephala on Nakoudo‐jima. Grassland cover also increased following feral goat elimination, but this may have occurred prior to L. leucocephala expansion. These results suggest that L. leucocephala‐dominated forest might invade grassland areas and that grasslands may have mediated the expansion of L. leucocephala after feral goat elimination. Future management of L. leucocephala should target the species in the high‐risk expansion zones adjacent to grasslands.  相似文献   

Pathology of cutaneous fowlpox with amyloidosis in layer hens inoculated with fowlpox vaccine     

Nakamura K  Waseda K  Yamamoto Y  Yamada M  Nakazawa M  Hata E  Terazaki T  Enya A  Imada T  Imai K 《Avian diseases》2006,50(1):152-156

Cutaneous fowlpox occurring in vaccinated layer hens was investigated pathologically and microbiologically. Anorexia, decrease of egg production, increased mortality, yellow scabs on faces, and alopecia of feathered skins with yellow scabs were observed in affected hens. Histologically, proliferative and necrotic dermatitis with eosinophilic ring-shaped cytoplasmic inclusions (Bollinger bodies) and clumps of gram-positive cocci (Staphylococcus hyicus) were noted in the affected birds. Fowlpox lesions were primarily observed in the feathered skins. Proliferation of feather follicle epidermal cells, with cytoplasmic inclusions and degeneration of the feather, and bacterial clumps in the feather follicles were noted in the affected skins. Ultrastructurally, characteristic fowlpox viral particles were observed in the cytoplasmic inclusions of hyperplastic epidermal cells. Amyloid deposition was observed in the Disse space of the liver, splenic sinus, and lamina propria of the bronchiolar, bronchial, and tracheal areas. Amyloidosis could be one factor inducing the fowlpox infection in vaccinated chickens.  相似文献   

In vitro assessment of the antiparasitic effect of caprylic acid against several fish parasites   总被引：3，自引：0，他引：3  

Noritaka Hirazawa  Syun-ichirou Oshima  Kazuhiko Hata 《Aquaculture (Amsterdam, Netherlands)》2001,200(3-4):251-258

The antiparasitic effect of caprylic acid against several fish parasites, i.e., the ciliate Cryptocaryon irritans (theronts), monogenean Benedenia seriolae (oncomiracidia and adults), copepod Pseudocaligus fugu (copepodids and adults) and myxosporean Kudoa shiomitsui (spores), was examined by in vitro trials.

Caprylic acid at a concentration of 1 mM had a parasiticidal effect against C. irritans theronts, B. seriolae oncomiracidia and K. shiomitsui spores and a contractile effect against B. seriolae adults, but had no clear effect against P. fugu copepodids and adults. These results suggest that caprylic acid may have an antiparasitic effect against various fish parasites, including parasites classified as monogenea, ciliates and myxosporea.  相似文献   

Histopathology of acute colchicine intoxication: novel findings and their association with clinical manifestations     

Shojiro Ichimata  Yukiko Hata  Kojiro Hirota  Naoki Nishida 《Journal of toxicologic pathology》2022,35(3):255

A 32-year-old woman attempted suicide by ingesting Gloriosa bulbs and died approximately 2 days later. Toxicological examination revealed a potentially fatal blood concentration of colchicine (0.096 mg/L). In addition to the increased mitotic figures in the gastrointestinal mucosa, a unique finding for acute colchicine intoxication, pathological examination showed microvesicular lipid droplets in the liver, kidney, heart, and conduction system. Furthermore, central chromatolysis of neurons was observed in the pontine nucleus, medial accessory olivary nucleus, nucleus of the solitary tract, and nucleus ambiguus. Grumose degeneration of the cerebellar dentate nucleus was also evident. These pathological findings may help identify colchicine intoxication, even in the absence of evidence suggesting ingestion during autopsy. Moreover, pathological changes in the heart and central nervous system may be associated with the development of serious complications of acute colchicine intoxication.  相似文献   

Molecular typing of Staphylococcus aureus isolated from bovine mastitic milk on the basis of toxin genes and coagulase gene polymorphisms   总被引：3，自引：0，他引：3  

Katsuda K  Hata E  Kobayashi H  Kohmoto M  Kawashima K  Tsunemitsu H  Eguchi M 《Veterinary microbiology》2005,105(3-4):301-305

A total of 270 strains of Staphylococcus aureus, isolated from mastitic milk, were investigated by the polymerase chain reaction for the presence of genes encoding enterotoxins (sea to sej) and a toxic shock syndrome toxin (tst). One hundred eighty three (67.8%) bovine isolates possessed either one or more toxin genes and the most common pattern that coexisted in S. aureus was tst, sec, seg, and sei. Coagulase genotyping revealed 15 patterns, and 161 of the 270 isolates (59.6%) belonged to the coagulase genotype B1. Further, these 161 isolates possessed at least two enterotoxin genes. However, the role of these toxins in udder pathogenicity remains unclear. Moreover, the predominant isolate possessed the enterotoxin genes supporting the theory that superantigenic toxins are important for the udder pathogenesis.  相似文献   

Immunochemical proof that a novel rearranging gene encodes the T cell receptor delta subunit   总被引：58，自引：0，他引：58  

H Band  F Hochstenbach  J McLean  S Hata  M S Krangel  M B Brenner 《Science (New York, N.Y.)》1987,238(4827):682-684

The T cell receptor (TCR) delta protein is expressed as part of a heterodimer with TCR gamma, in association with the CD3 polypeptides on a subset of functional peripheral blood T lymphocytes, thymocytes, and certain leukemic T cell lines. A monoclonal antibody directed against TCR delta was produced that binds specifically to the surface of several TCR gamma delta cell lines and immunoprecipitates the TCR gamma delta as a heterodimer from Triton X-100 detergent lysates and also immunoprecipitates the TCR delta subunit alone after chain separation. A candidate human TCR delta complementary DNA clone (IDP2 O-240/38), reported in a companion paper, was isolated by the subtractive library approach from a TCR gamma delta cell line. This complementary DNA clone was used to direct the synthesis of a polypeptide that is specifically recognized by the monoclonal antibody to TCR delta. This complementary DNA clone thus corresponds to the gene that encodes the TCR delta subunit.  相似文献   

Molecular characterization and analysis of equine rotavirus circulating in Japan from 2003 to 2008     

Nemoto M  Tsunemitsu H  Imagawa H  Hata H  Higuchi T  Sato S  Orita Y  Sugita S  Bannai H  Tsujimura K  Yamanaka T  Kondo T  Matsumura T 《Veterinary microbiology》2011,152(1-2):67-73

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Differences in leafminer (Phyllonorycter, Gracillariidae, Lepidoptera) and aphid (Tuberculatus, Aphididae, Hemiptera) composition among Quercusdentata, Q. crispula, Q. serrata, and their hybrids     

Yoshihiro Hata  Takuto Hashiba  Takashi Nakamura  Masashi Kitamura  Takahide A. Ishida  Shin-ichi Akimoto  Hiroaki Sato  Masahito T. Kimura 《Journal of Forest Research》2011,16(4):309-318

Leafminer (Phyllonorycter, Gracillariidae, Lepidoptera) and aphid (Tuberculatus, Aphididae, Hemiptera) composition were studied in three deciduous oak species, Quercus dentata, Q. crispula, and Q. serrata, and their hybrids in Tomakomai Experimental Forest of Hokkaido University, Hokkaido, northern Japan. Identification of trees in this forest was done mainly on the basis of discriminant analysis on leaf morphology with reference to trees in pure Q. dentata and Q. crispula stands and a Q. serrata stand mixed with Q. crispula. The results suggested that hybridization occurred in all combinations (i.e. Q. dentata–Q. crispula, Q. crispula–Q. serrata, and Q. serrata–Q. dentata) and the frequency of hybrids was approximately 10%. The composition of Phyllonorycter and Tuberculatus species differed between Q. dentata and Q. crispula or Q. serrata, but did not differ between Q. crispula and Q. serrata. Thus, Q. dentata could differ from Q. crispula and Q. serrata in chemical properties that determine herbivore host selection, survival, and performance, possibly reflecting eco-physiological differences or phylogenetic distances. The study insects were divided into three groups: species specialized to Q. dentata (three Phyllonorycter and one Tuberculatus species), those to Q. crispula and Q. serrata (six Phyllonorycter and two Tuberculatus species), and a species collected at least from Q. dentata and Q. crispula (one Tuberculatus species). Putative hybrid trees of Q. dentata and Q. crispula harbored both Q. dentata-specific and Q. crispula-specific insects.  相似文献   

Extensive junctional diversity of rearranged human T cell receptor delta genes   总被引：21，自引：0，他引：21  

S Hata  K Satyanarayana  P Devlin  H Band  J McLean  J L Strominger  M B Brenner  M S Krangel 《Science (New York, N.Y.)》1988,240(4858):1541-1544

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Evaluation of krill (Euphausia superba) meal as a partial replacement for fish meal in rainbow trout (Oncorhynchus mykiss) diets     

Bunji Yoshitomi  Masatoshi Aoki  Kazuhiko Hata 《Aquaculture (Amsterdam, Netherlands)》2006,261(1):440-446

We studied partial replacement of fish meal (FM) by krill meal (KM) and how fluoride from KM enriched-muscles and bones of rainbow trout reared in freshwater affected these fish. Diets that replaced FM with KM at proportions of 0, 7, 15 and 30% (control, KM7, KM15, and KM30) were fed to groups of rainbow trout for 92 days and growth was observed. In fish fed KM7 and KM15, weight gain (WG), feed intake (FI) and specific growth rate (SGR) were unchanged compared with fish fed the control diet, but in fish fed KM30, WG, FI and SGR significantly decreased. After the experiment, fluoride concentration in dorsal muscles of each experimental group was below the detected limit (1 mg/kg), but in vertebral bones, the fluoride concentration increased with each increase in KM inclusion in the diets: 490 mg/kg (control), 755 mg/kg (KM7), 1100 mg/kg (KM15), and 2400 mg/kg (KM30). Tissue specimens of liver of each experimental group had no histopathological changes. Therefore, accumulation of fluoride in vertebral bones apparently adversely affected growth of the vertebral bones thus affecting the growth performance as shown by the decrease in WG, FI and SGR.  相似文献