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31.
Parasitism by parasitoid wasps on the larvae of Epinotia granitalis (Butler), which is a wood-injuring pest in coniferous plantations, was observed for 6 years in two plantation forests of
Chamaecyparis obtusa (Sieb. et Zucc.) Endl. and Cryptomeria japonica (L.f.) D. Don that were adjacent to each other and consisted of trees of almost the same size. E. granitalis larvae were collected from early April to mid-May, then reared in glass bottles, and finally examined to determine whether
or not the larvae had been parasitized. Five species of parasitoids were recorded; two of them were classified in Ichneumonidae,
Campoplex spp. A and B, and others in Braconidae, Iconella repleta Papp, Bassus cingulipes Nees von Esenbeck, and Bracon spp. In all 6 years, parasitism was first observed around 20 April. Species composition of parasitoids differed greatly among
years and between forests. In 1 year in each forest the percentage parasitism increased significantly with the sampling date,
indicating that not all parasitoids attack the same developmental stage of E. granitalis. The mean percentage parasitism per year was significantly higher in the forest of C. obtusa [11.5(%) ± 5.7(SD)] than in the forest of C. japonica (3.0 ± 4.1). These results suggest that the efficiency of parasitoid adults in finding hosts differed between the two forests.
Received: September 20, 2001 / Accepted: August 5, 2002
Acknowledgments We are grateful to Dr. K. Maeto, Shikoku Research Center, Forestry and Forest Products Research Institute, and to Dr. K.
Konishi, National Agricultural Research Center for Hokkaido Region, for identifying parasitoids, and to Dr. T. Miyaura, Forest
Tree Breeding Center, and Dr. H. Kosaka, Forestry and Forest Products Research Institute, for their helpful advice throughout
the study.
Correspondence to:K. Kato 相似文献
32.
Antibodies can swiftly provide therapeutics to target disease-related molecules
discovered in genomic research. Antibody engineering techniques have been actively
developed and these technological innovations have intensified the development of
therapeutic antibodies. From the mid-1990’s, a series of therapeutic antibodies were
launched that are now being used in clinic. The disease areas that therapeutic antibodies
can target have subsequently expanded, and antibodies are currently utilized as
pharmaceuticals for cancer, inflammatory disease, organ transplantation, cardiovascular
disease, infection, respiratory disease, ophthalmologic disease, and so on. This paper
briefly describes the modes of action of therapeutic antibodies. Several non-clinical
study results of the pathological changes induced by therapeutic antibodies are also
presented to aid the future assessment of the toxic potential of an antibody developed as
a therapeutic. 相似文献
33.
Satoshi KAMBAYASHI Masaya IGASE Kosuke KOBAYASHI Ayana KIMURA Takako SHIMOKAWA MIYAMA Kenji BABA Shunsuke NOGUCHI Takuya MIZUNO Masaru OKUDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1405-1412
Hypoxic conditions in various cancers are believed to relate with their
malignancy, and hypoxia inducible factor-1α (HIF-1α) has been shown to be a major
regulator of the response to low oxygen. In this study, we examined HIF-1α expression in
canine lymphoma using cell lines and clinical samples and found that these cells expressed
HIF-1α. Moreover, the HIF-1α inhibitors, echinomycin, YC-1 and 2-methoxyestradiol,
suppressed the proliferation of canine lymphoma cell lines. In a xenograft model using
NOD/scid mice, echinomycin treatment resulted in a dose-dependent regression of the tumor.
Our results suggest that HIF-1α contributes to the proliferation and/or survival of canine
lymphoma cells. Therefore, HIF-1α inhibitors may be potential agents to treat canine
lymphoma. 相似文献
34.
Takeshi OHTA Shuichi KIMURA Masaya HIRATA Takahisa YAMADA Toshie SUGIYAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1327-1330
The Spontaneously Diabetic Torii (SDT) fatty rat, a model for obese type 2 diabetes,
shows bone quantitative abnormalities, namely low bone mineral density (BMD). The
objective of this study was to evaluate bone morphological changes, in particular
identifying the bone qualitative abnormalities, in the SDT fatty rat. Male SDT fatty rats
showed increases in total trabecular area and trabecular number and decreases in
trabecular thickness in cancellous bones of the proximal tibia, indicating trabecular
miniaturization. The SDT fatty rat is useful for investigation of pathophysiological
changes in bone quality in diabetic osteoporosis. 相似文献
35.
36.
Masatomi Hosoi Chuya Shinzato Masaya Takagi Shoko Hosoi-Tanabe Hideki Sawada Eri Terasawa Haruhiko Toyohara 《Fisheries Science》2007,73(2):385-394
ABSTRACT: Taurine is the primary osmolyte in marine molluscs, whose cellular osmo-conforming process is vital for environmental adaptation because of a lack of osmotic homeostasis. Here, cDNA cloning and expression, and functional analyses of taurine transporter (TAUT) from the giant Pacific oyster are reported on. The deduced amino-acid sequence of oyster TAUT (oyTAUT) showed 47–51% identity to those of vertebrate TAUT, whereas identity among the vertebrates is 78–95%. Functional analysis of oyTAUT expressed in Xenopus oocytes revealed that oyTAUT has a lower affinity and specificity for taurine and a requirement for higher NaCl concentration, compared with vertebrate TAUT. Taken together with similar functional properties of TAUT from mussel, indicated by our previous study, it is possible that these functional features reflect the internal environment of the molluscs (i.e. higher taurine and NaCl concentrations). Oyster taurine transporter mRNA expression was induced by not only hyper-osmotic stress, similar to other TAUT, but also hypo-osmotic stress. It is speculated that the expression in response to hypo-osmotic stress was induced by a substantial decrease in tissue taurine content following the decrease in the internal osmolality. 相似文献
37.
38.
- The most western little penguin colony globally, and the most northern in Western Australia (WA) is found on Penguin Island, WA. The penguins use coastal bays that are also used extensively by recreational watercraft. These penguins have been found to either dive predominantly to shallow depths of 1–5 m or to depths >8 m. It is thus hypothesized that (a) both the shallow and deeper diving penguins can potentially be disturbed or injured by these watercraft but that the risk will differ between the two diving strategies, and (b) that risk of injury for both is greater during the summer and autumn, when people are more likely to use watercraft.
- This was tested by attaching data loggers to little penguins during chick rearing and by investigating necropsy records. Diving activity was studied for the very shallow and relatively deeper diving penguins separately, and we considered the penguins were vulnerable to interactions with watercraft when they were within the top 2 m of the water column or at the surface.
- Shallow‐diving penguins executed >1,200 dives per day, 64% of dives occurred within the top 2 m, and they were vulnerable for approximately two‐thirds of their time at sea. The deeper diving penguins executed fewer dives. Almost half of dives were to ≥10 m, yet they were vulnerable for almost one‐third of their time at sea. Their post‐dive recovery was also longer. Thus, the risk of interaction from watercraft differs depending on the diving behaviour.
- This study highlights the potential impact to little penguins throughout Australia and New Zealand.
39.
Walmir Ribeiro de Carvalho Steel Silva Vasconcelos Osvaldo Ryohei Kato Carlos José Bispo Capela Débora Cristina Castellani 《Agroforestry Systems》2014,88(2):357-368
The current expansion of the oil palm (Elaeis guineensis Jacq.) in the Brazilian Amazon has mainly occurred within smallholder agricultural and degraded areas. Under the social and environmental scenarios associated with these areas, oil palm-based agroforestry systems represent a potentially sustainable method of expanding the crop. The capacity of such systems to store carbon (C) in the soil is an important ecosystem service that is currently not well understood. Here, we quantified the spatial variation of soil C stocks in young (2.5-year-old) oil palm-based agroforestry systems with contrasting species diversity (high vs. low); both systems were compared with a ~10-year-old forest regrowth site and a 9-year-old traditional agroforestry system. The oil palm-based agroforestry system consisted of series of double rows of oil palm and strips of various herbaceous, shrub, and tree species. The mean (±standard error) soil C stocks at 0–50 cm depth were significantly higher in the low (91.8 ± 3.1 Mg C ha?1) and high (87.6 ± 3.3 Mg C ha?1) species diversity oil palm-based agroforestry systems than in the forest regrowth (71.0 ± 2.4 Mg C ha?1) and traditional agroforestry (68.4 ± 4.9 Mg C ha?1) sites. In general, no clear spatial pattern of soil C stocks could be identified in the oil palm-based agroforestry systems. The significant difference in soil carbon between the oil palm area (under oil palm: 12.7 ± 2.3 Mg C ha?1 and between oil palm: 10.6 ± 0.5 Mg C ha?1) and the strip area (17.0 ± 1.4 Mg C ha?1) at 0–5 cm depth very likely reflects the high input of organic fertilizer in the strip area of the high species diversity oil palm-based agroforestry system treatment. Overall, our results indicate a high level of early net accumulation of soil C in the oil palm-based agroforestry systems (6.6–8.3 Mg C ha?1 year?1) that likely reflects the combination of fire-free land preparation, organic fertilization, and the input of plant residues from pruning and weeding. 相似文献
40.
Masayuki?Takahashi Takeshi?Yamamoto Sanae?Kato Kunihiko?KonnoEmail author 《Fisheries Science》2005,71(3):662-671
ABSTRACT: The effect of salt concentration on the thermal denaturation profile of myosin in walleye pollack and carp myofibrils was compared by studying the subfragment-1 (S-1) and rod denaturation rates upon heating. Species-specific denaturation mode observed at 0.1 M KCl was no longer detected when samples were heated above 0.5 M KCl, where S-1 and rod denaturation rates were identical to each other. As the heating of the chymotryptic digest of myofibril formed practically no rod aggregates, S-1 denaturation in a form of myosin was the rate limiting step for rod aggregate formation. As the aggregate formation by rod was remarkably suppressed by lowering the temperature, the free movement of myosin tail upon heating was suggested to play an important role in the rod aggregate formation in a high salt medium. 相似文献