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11.
We evaluated whether a bovine intestinal epithelial (BIE) cell line could serve as a useful in vitro model system for studying antiviral immune responses in bovine intestinal epithelial cells (IECs) and for the primary screening of immunobiotic microorganisms with antiviral protective capabilities. Immunofluorescent analyses revealed that toll-like receptor 3 (TLR3) was expressed in BIE cells, and the results of real-time quantitative PCR showed that these cells respond to stimulation with poly(I:C) by up-regulating pro-inflammatory cytokines and type I interferons. In addition, we demonstrated that BIE cells are useful for the primary screening of immunobiotic lactic acid bacteria strains which are able to beneficially modulate antiviral immune responses triggered by TLR3 activation in bovine IECs. The characterization of BIE cells performed in the present study represents an important step towards the establishment of a valuable bovine in vitro system that could be used for the development of immunomodulatory feed for bovine hosts.  相似文献   
12.
The health hazards of individual organophosphorus insecticides have been characterized by their acute toxicity, mainly by investigating their cholinesterase inhibition. However, the chronic effects of most of these toxicants on the drug-metabolizing enzymes have not been investigated. Profenofos (O-4-bromo-2-chlorophenyl O-ethyl S-propyl phosphorothioate) is an organophosphorus pesticide widely used in cotton cultivation. In the present study, we investigated the effect of profenofos on male-specific cytochrome P450 (CYP) enzymes in adult Wistar rats. We orally administered 17.8 mg/kg body weight, twice weekly for 65 days. Profenofos downregulated levels of hepatic and testicular CYP2C11 and CYP3A2 mRNA and protein expression. Testicular aromatase (CYP19A) mRNA was decreased in the profenofos-treated rats compared to controls. Overall, the present study suggests that profenofos acts as an endocrine disruptor of male-specific CYP enzymes and affects testosterone concentration, which implicates its deleterious effects on animal or human males chronically exposed to organophosphorus pesticide.  相似文献   
13.
A kuroko-type polymetallic sulfide deposit in a submarine silicic caldera   总被引:1,自引:0,他引:1  
Manned submersible studies have delineated a large and actively growing Kuroko-type volcanogenic massive sulfide deposit 400 kilometers south of Tokyo in Myojin Knoll submarine caldera. The sulfide body is located on the caldera floor at a depth of 1210 to 1360 meters, has an area of 400 by 400 by 30 meters, and is notably rich in gold and silver. The discovery of a large Kuroko-type polymetallic sulfide deposit in this arc-front caldera raises the possibility that the numerous unexplored submarine silicic calderas elsewhere might have similar deposits.  相似文献   
14.
Bioassays were adapted to investigate effects of droplet size and carrier volume on performance of daminozide, gibberellic acid (GA3) and 2,4-D using Phaseolus vulgaris L. as a model system. Response to plant growth regulators was indexed by inhibition (daminozide), promotion of internode elongation (GA3) or ethylene production (2,4-D). Elongation of first plus second internodes above primary leaves was evaluated 14 days after treatment of primary leaves, while ethylene production was determined from head-space samples of incubated leaves 24 h after treatment. Daminozide inhibition of internode elongation was related to decreased cell size and number in pith and epidermis (range 49–70% of the untreated control). GA3 increased cell size and number in both tissues 2·3- to 4·8-fold. Responsiveness to daminozide and 2,4-D markedly decreased as seedling age increased from 8 to 12 days, but responsiveness to GA3 increased. Decreasing droplet size (10–0·5 μl) and increasing carrier volume (10–200 μl per leaf) at constant dose of daminozide (100 μg per leaf) and 2,4-D (100 μg per leaf) significantly increased performance, but had little effect on performance of GA3 (2 μg per leaf). Effects of application factors on performance were related to their effects on the interface area between droplets and leaf surface. Significant positive linear relationships were obtained between plant response and the logarithm of the droplet/leaf interface area for all growth regulators. © 1998 Society of Chemical Industry  相似文献   
15.
We compared differences in leaf properties, leaf gas exchange and photochemical properties between drought-deciduous and evergreen trees in tropical dry forests, where soil nutrients differed but rainfall was similar. Three canopy trees (Shorea siamensis Miq., Xylia xylocarpa (Roxb.) W. Theob. and Vitex peduncularis Wall. ex Schauer) in a drought-deciduous forest and a canopy tree (Hopea ferrea Lanessan) in an evergreen forest were selected. Soil nutrient availability is lower in the evergreen forest than in the deciduous forest. Compared with the evergreen tree, the deciduous trees had shorter leaf life spans, lower leaf masses per area, higher leaf mass-based nitrogen (N) contents, higher leaf mass-based photosynthetic rates (mass-based P(n)), higher leaf N-based P(n), higher daily maximum stomatal conductance (g(s)) and wider conduits in wood xylem. Mass-based P(n) decreased from the wet to the dry season for all species. Following onset of the dry season, daily maximum g(s) and sensitivity of g(s) to leaf-to-air vapor pressure deficit remained relatively unchanged in the deciduous trees, whereas both properties decreased in the evergreen tree during the dry season. Photochemical capacity and non-photochemical quenching (NPQ) of photosystem II (PSII) also remained relatively unchanged in the deciduous trees even after the onset of the dry season. In contrast, photochemical capacity decreased and NPQ increased in the evergreen tree during the dry season, indicating that the leaves coped with prolonged drought by down-regulating PSII. Thus, the drought-avoidant deciduous species were characterized by high N allocation for leaf carbon assimilation, high water use and photoinhibition avoidance, whereas the drought-tolerant evergreen was characterized by low N allocation for leaf carbon assimilation, conservative water use and photoinhibition tolerance.  相似文献   
16.
CYP2D-related drug metabolism in liver microsomes from animals of the Canoidea super family, i.e. mink (Mustela vison), bears (Ursus arctos), foxes (Vulpes vulpes) and dogs, were investigated. Propranolol, bunitrolol and imipramine, which are typically substrates of CYP2D subfamilies, were used in the experiment. All the animals of the Canoidea superfamily that were tested lacked the ability to catalyse 7-hydroxylation of propranolol, which is one of the major metabolic pathways in rats. Stereoselectivity of propranolol metabolism was towards (S)-propranolol in all the reactions of the animals tested with the exception of mink, which showed a selective tendency towards (R)-propranolol in N-dealkylation. As far as metabolic patterns of (R)- and (S)-propranolol are concerned, bears, foxes and dogs are alike, but minks are somewhat different. Liver microsomes from mink showed, among the animals of the Canoidea superfamily, the lowest propranolol hydroxylase activity at 4- and 5-positions and imipramine 2-hydroxylation and {N-}demethylation activities. We could not detect bunitrolol 4-hydroxylation in mink liver microsomes at the low substrate concentration used. We conclude that mink have the lowest activity of CYP2D-related xenobiotic metabolism among the Canoidea superfamily.  相似文献   
17.

Background  

The ambrosia beetle, Platypus quercivorus, is the vector of oak wilt, one of the most serious forest diseases in Japan. Population genetics approaches have made great progress toward studying the population dynamics of pests, especially for estimating dispersal. Knowledge of the genetic structuring of the beetle populations should reveal their population history. Using five highly polymorphic microsatellite loci, 605 individuals from 14 sampling sites were assessed to infer the ongoing gene flow among populations as well as the processes of expansion of damaged areas.  相似文献   
18.
Photodynamic detection using 5-aminolevulinic acid has been used to identify the surgical margins during resection of human primary brain tumours. Although there are some reports on its use in malignant tumours in veterinary medicine, it has never been used for primary brain tumours. Here we describe a canine glioblastoma that was detected at autopsy with protoporphyrin IX fluorescence induced by orally administered 5-aminolevulinic acid. The fluorescence was strongest towards the centre of the lesion and was absent in normal brain tissue. Moreover, the fluorescence findings were consistent with MRI and histopathological findings. Our findings suggest that photodynamic detection using 5-aminolevulinic acid might be useful for intraoperative fluorescence-guided resection of malignant gliomas in dogs.  相似文献   
19.
For examining the probability of increase in the occupation ratio of inoculated rhizobium in nodules, various Rj-soybean cultivars including the Rj 2 Rj 3 Rj 4-lines of soybean were grown in a field of the Kyushu University Farm. Bradyrhizobium japonicum USDA110 that carries uptake hydrogenase (Hup+) was used as an inoculum. The relative efficiency of nitrogen fixation generally increased by the inoculation. However, there were no significant differences in the effects among the genotypes of the host plants. The occupation ratio of serogroup USDA110 in the nodules on the taproot of the inoculated plants was in the range of 77–100%, suggesting that the B. japonicum strain USDA110 infected taproots immediately after inoculation. The occupation ratios in the nodules on the lateral roots were 53–67, 40–86, 63–83, and 62–77% in inoculated plants of the non-Rj-, Rj 2 Rj 3-, Rj 4-, and Rj 2 Rj 3 Rj 4-genotypes, respectively, and they decreased in all the genotypes with the progression of growth. At the time of the first sampling, the occupation ratios on the lateral roots of these Rj 2 Rj 3 Rj 4-genotypes showed values intermediate between those of IAC-2 (Rj 2 Rj 3) and Hill (Rj 4) , which were the parent cultivars of the Rj 2 Rj 3 Rj 4-lines, B340, B349, and C242. The reduction in the occupation ratio of the serogroup USDA110 for about 1 month after the first sampling was the lowest (0.13–0.16) in the Rj 2 Rj 3 Rj 4-genotypes, excluding B349, followed by the non-Rj- and Rj 2 Rj 3-genotypes and highest (0.52–0.69) in the Rj 4-genotypes, excluding Hill. Therefore, it was considered that the population of compatible rhizobia with host soybean plants increased in the rhizosphere with the progression of the development and growth. The results showed that with the expansion of the root area of host plants, the occupation ratio of type A rhizobia including the serogroup USDA110 was high. Therefore, the Rj 2 Rj 3 Rj 4-genotypes were superior to other Rj-genotypes in terms of the inoculation effects of nodulation type A rhizobium, B. japonicum USDA110. However, the preference of the Rj 2 Rj 3 Rj 4-genotype for serogroup USDA110 is not sufficient to rule out the competition with the other serogroups in this study. Therefore, the study should be centered on the isolation of more efficient (Hup+) and highly compatible rhizobial strains with the Rj 2 Rj 3 Rj 4- genotypes.  相似文献   
20.
Estimating carbon (C) and nitrogen (N) stocks in deadwood in forests nationwide is required for understanding large-scale C and N cycling. To do so requires estimated values of wood density and C and N concentrations. Additionally, parameters that show variation should be examined. In this study, we clarified the estimated values and the variation in three parameters in each decay class of each of two tree species and examined whether dead log diameter and region contribute to variation in the parameters. Data were collected from 73 Chamaecyparis obtusa (Sieb. et Zucc.) Endl. plantations and 66 Cryptomeria japonica D. Don plantations throughout Japan. Wood densities decreased from 386 to 188?kg?m?3 for C. obtusa and from 334 to 188?kg?m?3 for C. japonica in decay classes 1–4. The variation in wood density increased with decay class, and the coefficient of variance increased from 13.9% to 46.4% for C. obtusa and from 15.2% to 48.1% for C. japonica. The N concentrations increased from 1.04 to 4.40?g?kg?1 for C. obtusa and from 1.11 to 2.97?g?kg?1 for C. japonica in decay classes 1–4. The variation in N concentration increased with decay class, and the coefficient of variance increased from 51.9% to 76.7% for C. obtusa and from 50.3% to 70.4% for C. japonica. Log diameter and region contributed to variations in wood density and N concentration in decay classes 1 and 2 for C. obtusa and C. japonica. However, no relationship was observed between regional climates and the two parameters. In contrast, C concentrations ranged from 507 to 535?g?kg?1 and were stable with much lower coefficients of variance throughout the decay classes for both tree species. Thus, we recommend that the same C concentration can be adapted for all decay classes of both tree species.  相似文献   
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