Search PubMed⌕ Search

Biomedical subjects

K Fujisaki

Publications and source records attributed to K Fujisaki.

142 records · Page 8Linked to original sources

Rapid detection by counterimmunoelectrophoresis of antigens and antibodies in the sera of chickens infected with Leucocytozoon caulleryi.

The method of counterimmunoelectrophoresis was used to detect rapidly soluble antigens and antibodies in the sera of chickens infected with Leucocytozoon caulleryi. This method retained the specificity revealed by the Ouchterlony gel-diffusion technique, and induced no false positive reactions. Therefore, it was applicable to the serological diagnosis of chicken leucocytozoonosis, as well as the Ouchterlony technique which is used in Japan at present.

Animals↗

Development of acquired resistance precipitating antibody in rabbits experimentally infested with females of Haemaphysalis longicornis (Ixodoidea: Ixodidae).

The resistance to the ixodid tick, Haemaphysalis longicornis (parthenogenetic Okayama strain), manifested as a reduction in engorged body weight, developed in rabbits subjected to a series of adult female infestations. A single infestation with females always produced resistance in hosts. This production appeared to depend little on the number of ticks per infestation. Unlike the previous papers, this study revealed that there was no reduction in the mean recovery rate of engorged females when ticks fed on a rabbit repeatedly infested with the ticks. A series of infestations were carried out comparatively to investigate the major biological characters of ticks, such as feeding, oviposition, and hatchability of eggs. As a result, there were no marked differences in these characters among the infestations. Especially, no differences were noticed in the concentration of ingested blood meal in detached females among the infestations. Precipitating antibodies were found in the sera of rabbits resistant to the tick-bite. They were subjected to fractionation by Sephadex G-200 chromatography and tested for sensitivity to 2-mercaptoethanol. As a result, they were proved to be of immunoglobulin of 7 S class.

Animals↗

Development of Leucocytozoon caulleryi in chick embryos infected by biting of Culicoides arakawae through shell membrane.

Chick embryos were infected with Leucocytozoon caulleryi by biting of the midge, Culicoides arakawae, through the shell membrane. Schizonts of L. caulleryi were detected in the chorioallantoic membrane and most of the internal organs of embryos and of chicks after hatching. The development of schizonts was slower in embryos than in chickens. Soluble antigens of L. caulleryi were demonstrated by the precipitation test in the allantoic fluid and blood from the embryos and chicks. No erythrocytic stage of L. caulleryi, however, was observed in any embryo or chick.

Animals↗

Accumulating process and concentration ratios of ingested blood meals in larvae and nymphs of ten species of ticks.

The accumulating process and concentration ratios of ingested blood meals in the larvae and nymphs of Amblyomma testudinarium, Haemaphysalis campanulata, H. concinna, H. formosensis, H. hystricis, H. kitaokai, the bisexual and parthenogenetic strains of H. longicornis, H. megaspinosa, and Ixodes persulcatus on rabbits and Argas japonicus on chickens were comparatively investigated. The larvae and nymphs of the ixodid ticks examined and the larvae of A. japonicus concentrated the ingested blood meals up to about 3 times. In general, the larvae showed low concentration ratios due to their tendency to imbibe a certain proportion of non-blood components. The nymphs generally showed high concentration ratios. H. kitaokai belongs to the subgenus Alloceraea, the members of which are unique rapid feeders. It showed a high activity in concentrating ingested blood meal and presented the same general pattern of feeding as the other ixodid ticks which are very slow feeders.

Animals↗

Comparative observations on some bionomics of Japanese ixodid ticks under laboratory cultural conditions.

Seventeen species of Japanese ixodid ticks of the genera Amblyomma, Boophilus, Haemaphysalis, Ixodes, and Rhipicephalus were reared in the laboratory under almost the same cultural conditions. Their major biological characters, such as feeding, molting, oviposition, and hatching, were summarized in tables. There were some differences in these bionomics among the species. The general characteristics common to all the ticks, except Amblyomma testudinarium, were as follows. The feeding period in immature stages and adult females was 3 approximately 5 and 7 approximately 14 days, respectively. The engorged body weight in larvae, numphs, and females was 0.3 approximately 0.5, 3.5 approximately 5.0, and 100 approximately 300 mg, respectively. The potential sexuality could be estimated from the nymphal engorged weight in five species. The larval and nymphal molting periods at 25 degrees C were alike, or 10 approximately 20 days, and there were no significant sexual differences in nymphal molting period among six species. The body weight just after molting in nymphs, males, and females was 0.25 approximately 0.3, 1 approximately 2, and 2 approximately 3 mg, respectively. The pre-oviposition, oviposition, and egg-incubation periods at 25 degrees C were 4 approximately 10 days, 2 approximately 3 weeks, and 1 month, respectively.

Animals↗

The effect of in situ freezing on rabbit patellar tendon. A histologic, biochemical, and biomechanical analysis.

Cell necrosis has been well documented as one of the many changes that occur in autogenous tendon when it is used to reconstruct the anterior cruciate ligament. The purpose of this experiment was to isolate cell necrosis as a variable and study its effect on the patellar tendon. To accomplish this, both knees of 25 New Zealand White rabbits were operated on. In one knee, a 5-mm wide band of patellar tendon was subjected to two rapid freeze-thaw cycles, while the other knee underwent sham surgery. Histologic evaluation showed a zone of necrosis at 2 and 4 weeks with cellular repopulation complete at 8 weeks. patellar tendon cross-sectional area was 0.118 cm2 at 8 weeks for the frozen specimens compared to 0.102 cm2 for the sham-operated controls. This difference was significant at the P = 0.025 level. Mechanical testing at 4 and 8 weeks revealed no significant changes in tendon length, maximum load, or stiffness. The collagen content was also unchanged at both 4 and 8 weeks.

Animals↗