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951.
The gene encoding an outer membrane lipoprotein (OmlA) of Actinobacillus pleuropneumoniae strain WF83 (serotype 7 reference strain), designated omlA7, was sequenced. The amino acid sequence of OmlA7 showed 64.5 and 71.6% identity to that of OmlA from serotypes 1 (OmlA1) and 5 (OmlA5), respectively. The first 134 amino acids of OmlA7 were identical to those of OmlA5. A Southern blot analysis revealed the presence of a gene highly homologous to the omlA7 in the reference strains of serotypes 3, 4, 6, and 7. A Western blot analysis using a specific antiserum against a recombinant OmlA7 detected expression of the homologous proteins in the serotypes 4, 6, and 7 reference strains and a serotype 3 field strain, but not in a serotype 3 reference strain. The data demonstrate the third antigenically distinct OmlA is expressed in A. pleuropneumoniae.  相似文献   
952.
Nonsteroidal anti-inflammatory drugs (NSAIDs) have chemopreventive activity and may be suitable for treatment of colorectal cancer. A popular and potent NSAID, indomethacin, is known to cause serious side-effects, for this reason its therapeutic usefulness is limited. However, these side-effects are likely to be attributed to the additional effects of indomethacin besides its cyclooxygenase inhibition. In this study, we examined the effect of indomethacin on arachidonic acid uptake using LS174T human colon cancer cells. We here show that treatment of LS174T cells with indomethacin reduced arachidonic acid uptake as well as reduced expressions of fatty acid translocase/CD36 and peroxisome proliferators-activated receptor γ. Since arachidonic acid is a major substrate of inflammatory mediators such as prostaglandins and leukotrienes, we believe this novel effect of indomethacin may apply to new treatment strategies that aim to suppress these mediators by decreasing the uptake of their substrates, which would eventually inhibit colorectal cancer malignancy.  相似文献   
953.
Two groups of hatchery-reared juveniles of Japanese flounder Paralichthys olivaceus (Temminck and Shlegel) were experimentally released in Wada Beach, Fukui Prefecture, Japan and their feeding state examined in comparison to wild juveniles to investigate the optimal release season and the relationship between food availability and feeding performance of juveniles. We released two groups of 40,000 juveniles of ca. 50 mm size, one group in the early (29 May) and the other in late (2 July) seasons, periods with predicted high and low densities of prey mysids, respectively, although the abundance of mysids fluctuated markedly during the season. Food availability was higher for the early release group than the late release group. Although the main stomach contents of released and wild juveniles were mainly mysids and fish, the feeding state differed between the early and late release groups. The early release group had a stomach content index (SI) similar to that of the wild juveniles, but the SI of the late group was significantly less than that of the early release group and wild juveniles. The percentage of fish with empty stomachs was much higher in the late release group than in the other two groups. In addition, the density decrease rate was significantly more rapid for the late release group than the early release group. Clear correspondence between the food availability and feeding state of the released flounder juveniles indicates that the release of juveniles in an appropriate season when mysids are abundant is crucial for successful stocking.  相似文献   
954.
955.
Intracellular asymmetry in the signaling network works as a compass to navigate eukaryotic chemotaxis in response to guidance cues. Although the compass variable can be derived from a self-organization dynamics, such as excitability, the responsible mechanism remains to be clarified. Here, we analyzed the spatiotemporal dynamics of the phosphatidylinositol 3,4,5-trisphosphate (PtdInsP3) pathway, which is crucial for chemotaxis. We show that spontaneous activation of PtdInsP3-enriched domains is generated by an intrinsic excitable system. Formation of the same signal domain could be triggered by various perturbations, such as short impulse perturbations that triggered the activation of intrinsic dynamics to form signal domains. We also observed the refractory behavior exhibited in typical excitable systems. We show that the chemotactic response of PtdInsP3 involves biasing the spontaneous excitation to orient the activation site toward the chemoattractant. Thus, this biased excitability embodies the compass variable that is responsible for both random cell migration and biased random walk. Our finding may explain how cells achieve high sensitivity to and robust coordination of the downstream activation that allows chemotactic behavior in the noisy environment outside and inside the cells.  相似文献   
956.
Thiosulfate was oxidized to tetrathionate and an unknown oxidized sulfur compound. The activity was found in the particulate fraction (a precipitate obtained by centrifuging (at 90,000 × g for 60 min) the supernatant of centrifugation at 10,000 × g for 30 min). Treatment with deoxycholate caused inactivation of the enzyme. Considering from these points and electronmicrograph, the enzyme would be located on the cell membrane.  相似文献   
957.
958.
Abstract. We have explored the process by which crinoids increase arm number as they grow. Two hypotheses have been proposed: (1) arm autotomy with subsequent bifurcation and regeneration of a pair of arms, and (2) growth of a pinnule into an additional arm. We have traced the development of Oxycomanthus japonicus for about a year after fertilization and provide the first confirmation that the number of arms increases by autotomy, bifurcation, and subsequent regeneration of a pair of arms. The next such addition tends to occur at some distance from the previous pair. Thus, increase of arm number takes place in such a manner that the density of the arms remains relatively constant, and an efficient filtration fan for feeding is maintained. Although arm autotomy in crinoids has been considered to occur only as a response to physical or chemical disturbance, the present results suggest that autotomy also occurs as a specific, intrinsically programmed event during normal development.  相似文献   
959.
960.
Epidemics of acute hemorrhagic conjunctivitis due to a coxsackievirus A24 variant occurred in July-November, 1985 and August-October, 1986 in Okinawa Prefecture, Japan. This is the first report of an acute hemorrhagic conjunctivitis epidemic due to a coxsackievirus A24 variant in Japan The epidemic involved most islands of the prefecture. The prefectural surveillance center was notified of 9,952 cases in 1985 and 6,096 cases in 1986 from three sentinel eye clinics. The neutralizing antibody-positive rate against the coxsackievirus A24 variant of the serum samples collected before and immediately after the 1985 epidemic rose from 1.0% to 8.5%. The coxsackievirus A24 variant was isolated from 48 out of 68 conjunctival swabs collected during the epidemics. The isolates were indistinguishable antigenically in the plaque reduction test from the prototype strain, EH24/70, but had a markedly distinct oligonucleotide pattern.  相似文献   
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