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41.
Growth Characteristics and Intraspecies Host Specificity of a Large Virus Infecting the Dinoflagellate Heterocapsa circularisquama 下载免费PDF全文
Keizo Nagasaki Yuji Tomaru Kenji Tarutani Noriaki Katanozaka Satoshi Yamanaka Hiroshi Tanabe Mineo Yamaguchi 《Applied microbiology》2003,69(5):2580-2586
The growth characteristics and intraspecies host specificity of Heterocapsa circularisquama virus (HcV), a large icosahedral virus specifically infecting the bivalve-killing dinoflagellate H. circularisquama, were examined. Exponentially growing host cells were more sensitive to HcV than those in the stationary phase, and host cells were more susceptible to HcV infection in the culture when a higher percent of the culture was replaced with fresh medium each day, suggesting an intimate relationship between virus sensitivity and the physiological condition of the host cells. HcV was infective over a wide range of temperatures, 15 to 30°C, and the latent period and burst size were estimated at 40 to 56 h and 1,800 to 2,440 infective particles, respectively. Transmission electron microscopy revealed that capsid formation began within 16 h postinfection, and mature virus particles appeared within 24 h postinfection at 20°C. Compared to Heterosigma akashiwo virus, HcV was more widely infectious to H. circularisquama strains that had been independently isolated in the western part of Japan, and only 5.3% of the host-virus combinations (53 host and 10 viral strains) showed resistance to viral infection. The present results are helpful in understanding the ecology of algal host-virus systems in nature. 相似文献
42.
Efficient production of IGG human monoclonal antibodies by lymphocytes stimulated by lipopolysaccharide,pokeweed mitogen,and interleukin 4 总被引:1,自引:0,他引:1
Kaoru Yoshinari Kenji Arai Hideki Kimura Kunio Matsumoto Yutaka Yamaguchi 《In vitro cellular & developmental biology. Animal》1996,32(6):372-377
Summary Extensive screening of the mitogens lipopolysaccharide (LPS), pokeweed mitogen (PWM), andStaphylococcus aureus Cowan I (SAC I), alone and in combination and with and without interleukin (IL) was performed forin vitro activation of regional lymph node lymphocytes from lung cancer patients for the production of human IgG, IgM, and IgA. As
assessed by electrofusion of the lymphocytes following their exposure to these agents with mouse myeloma cells and incubation
of the fused hybridoma, a remarkable stimulatory effect was shown by LPS and particularly by LPS plus IL-4, which was substantially
greater than that of either SAC I or PWM with or without various IL. Optimization studies indicated that the addition of PWM
to LPS and IL-4 in the culture medium further stimulated the human antibody (Ab) production, and that the optimal formulation
for stimulations of human IgG production was a culture medium containing 20 μg/ml of LPS, 1/500 of PWM, and 100 u/ml of IL-4. 相似文献
43.
Futoshi Aranishi Kenji Hara Kiyoshi Osatomi Tadashi Ishihara 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1996,114(4):371-376
Cathepsin B was purified from the crude extract of carp (Cyprinus carpio) hepato-pancreas by the method involving ammonium sulfate fractionation and five sequential chromatographies monitored the activity with Z-Arg-Arg-MCA as a substrate, and the specific activity increased about 11,400 fold with a 2% recovery. Although the homogeneity of the purified cathepsin B was established on Native-PAGE, it migrated as two bands of 29,000 and 25,000 molecular weights by the single and heavy chains on SDS-PAGE, respectively. The monospecific antibody against the homogeneous cathepsin B was purified by the affinity chromatography on cathepsin B-Sepharose 4B, and did not immunologically react with rat cathepsin B, carp cathepsins H and L but only with carp cathepsin B by immunoelectrophoretic blot analysis. As the result of the tissue and liver distributions of cathepsin B, the remarkable immunological reactivities in the extracts of spleen, kidney and hepato-pancreas in carp and those of pacific cod, yellow fin tuna, skip jack tuna and common mackerel in pisces were detected with the anti-carp hepato-pancreas cathepsin B at molecular weight of nearby 29,000 or 25,000. 相似文献
44.
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46.
Kenji Hara Henneke Pangkey Kiyoshi Osatomi Keiko Yatsuda Atsushi Hagiwara Katsuyasu Tachibana Tadashi Ishihara 《Hydrobiologia》1997,358(1-3):89-94
We examined some characteristics of hydrolyticenzymes, especially -1,3-glucanase, to obtain theinformation of cell wall lytic enzymes forrotifers.Crude enzyme (ammonium sulfate fraction) of rotifershydrolyzed starch, -1,3-glucan, glycol chitinand CM-cellulose. Optimum pH for hydrolysis ofstarch and CM-cellulose was 6.5, and that for -1,3glucan and glycol chitin was pH 6.0. Pectic acid,xylan and agarose were not hydrolyzed at pH 3–10.-1,3 glucanase was purified about 73-fold from crudeenzyme by ion-exchange chromatography and gelfiltration. Optimum pH and temperature of the enzymewere 6 and 60 °C, respectively. The molecular weight ofthe enzyme was estimated about 260 kDa by gelfiltration. The enzyme was inhibited byHgCl2 and MnCl_2. 相似文献
47.
Teruo Yamashita Kenji Sakae Shinichi Kobayashi Yuichi Ishihara Takashi Miyake Agboatwalla Mubina Shin Isomura 《Microbiology and immunology》1995,39(6):433-435
Aichi virus was isolated in Vero cells from 5 (2.3%) of 222 Pakistani children with gastroenteritis but none was found in 91 healthy children. Aichi virus was also isolated from 5 (0.7%) of 722 Japanese travelers returned from tours to Southeast Asian countries and complained of gastrointestinal symptoms at the quarantine station of Nagoya International Airport in Japan. Of 5 Japanese travelers, 3 were returning from Indonesia, and 2 from Thailand or Malaysia. These results indicate that Aichi virus or a similar agent is endemic in Southeast Asian countries and is a cause of gastrointestinal symptoms in children in these areas or in Japanese travelers who visit there. 相似文献
48.
H Nakajima S Kitabatake R Tsurutani I Tomioka K Yamamoto K Imahori 《Biochimica et biophysica acta》1984,790(2):197-199
Several kinds of dipeptide derivative were shown to be formed by the reactions of the aminoacyl adenylate-aminoacyl-tRNA synthetase complex and amino acid ester or amide. It was shown that the peptide bond could be formed by aminoacyl-tRNA synthetases even in the absence of the ribosome. 相似文献
49.
Measurement of Stomatal Aperture by Digital Image Processing 总被引:2,自引:0,他引:2
We developed a new digital image processing technique for exactlymeasuring the degree of stomatal opening, that is, the ratioof the width to the maximum length of a stomatal pore, and thepore area. We applied this technique to evaluate responses toSO2 of neighboring stomata in a small region of an intact attachedleaf, with the following results:
- The pore region could be exactly extracted even when the originaldigital image was of poor quality. The standard errors in theevaluation of the pore area, the pore length, and the pore widthwere 10 µm2, 0.3 µm and 0.3 µm, respectively.
- A wide variety of responses to SO2 was found among neighboringstomata in a small region of an attached leaf. The differenceswere especially remarkable before water-soaking and wilting.When these began, k1 showed a local maximum value, and thenall the stomata began to close. These results suggest that stomatalresponses of intact growing plants to air pollutants shouldbe examined from the standpoint of not only the average movementof many stomata but also the movement of each stoma and thatthe interrelationship among movements of neighboring stomatashould be investigated to clarify the mechanism of stomatalresponses to air pollutants.
50.
Treatment of Sendai virus with , followed by freezing and thawing resulted in a loss of hemolytic and cell fusion activities as well as infectivity without affecting hemagglutinating and neuraminidase activities. The anti-hemolytic activity of this compound was reversed by the addition of phosphatidyl choline to the virus samples. was successfully used for photoaffinity labeling of a specific virion site, and we confirmed the affected site of the glucoside to be the lipid components in the viral envelopes. 相似文献