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51.
BACKGROUND: Trichoderma asperellum SKT-1 is a microbial pesticide of seedborne diseases of rice. To investigate the mechanisms of disease suppression in SKT-1, the ability to induce systemic resistance by SKT-1, or its cell-free culture filtrate (CF), was tested using Arabidopsis thaliana Col-0 plants. RESULTS: Both SKT-1 and its CF elicit an induced systemic resistance against the bacterial leaf speck pathogen Pseudomonas syringae pv. tomato DC3000 in Col-0 plants. Involvement of plant hormones in the induced resistance by SKT-1 and CF was assessed using Arabidopsis genotypes such as the jasmonic acid (JA)-resistant mutant jar1, the ethylene (ET)-resistant mutant etr1, the plant impaired in salicylic acid (SA) signalling transgenic NahG and the mutant npr1 impaired in NPR1 activity. In soil experiments using SKT-1, no significant disease suppression effect was observed in NahG transgenic plants or npr1 mutant plants. Expression levels of SA-inducible genes such as PR-1, PR-2 and PR-5 increased substantially in the leaves of Col-0 plants. Expression levels of JA/ET-induced genes such as PDF1.2a, PR-3, PR-4 and AtVsp1 were also induced, but the levels were not as high as for SA-inducible genes. In a hydroponic experiment using CF from SKT-1, all Arabidopsis genotypes showed an induced systemic resistance by CF and increased expression levels of JA/ET- and SA-inducible genes in leaves of CF-treated plants. CONCLUSION: The SA signalling pathway is important in inducing systemic resistance to colonisation by SKT-1, and both SA and JA/ET signalling pathways combine in the signalling of induced resistance by CF. These results indicate that the response of A. thaliana is different from that found in root treatments with barley grain inoculum and CF from SKT-1. Copyright © 2011 Society of Chemical Industry  相似文献   
52.
A limbal melanoma was surgically removed from a 12-year-old castrated male black domestic shorthair (DSH) cat. The resulting full-thickness eye wall defect was repaired using the autologous third eyelid cartilage. The patient was followed for 85 days postoperatively, during which time there was no recurrence. Other than a small amount of fibrin and blood at the anterior lens capsule, no significant complications were seen. Use of the third eyelid cartilage as graft material following resection of a feline limbal melanoma can be effective for repairing large eye wall defects and preserving ocular function. The third eyelid proved to be a convenient source of graft material. In addition, autologous grafting can reduce the potential for iatrogenic spread of infectious agents such as feline herpes virus.  相似文献   
53.
The properties of garlic (Allium sativum L.) are attributed to organosulfur compounds. Although these compounds change during cultivation and storage, there is no report of their simultaneous analysis. Here, a newly developed analytical method with a rapid and simple sample preparation to determine four sulfoxides and three gamma-glutamyl peptides in garlic is reported. All garlic samples were simply extracted with 90% methanol solution containing 0.01 N hydrochloric acid and prepared for analysis. Alliin, isoalliin, methiin, cycloalliin, and gamma-l-glutamyl-S-methyl-l-cysteine were determined by normal-phase HPLC using an aminopropyl-bonded column. gamma-l-Glutamyl-S-(2-propenyl)-l-cysteine and gamma-l-glutamyl-S-(trans-1-propenyl)-l-cysteine were separated on an octadecylsilane column. The overall recoveries were 97.1-102.3%, and the relative standard deviation values of intra- and interday precision were lower than 2.6 and 4.6%, respectively. This newly developed method offers some advantages over the currently accepted techniques including specificity, speed, and ease of use and would be useful for chemical and biological studies of garlic and its preparations.  相似文献   
54.
Natural intoxication of livestock by the ingestion of Ipomoea carnea (Convolvulaceae) sometimes occurs in tropical regions of the world. Polyhydroxylated alkaloids were isolated from the leaves, flowers, and seeds of the poisonous plant and characterized. Chromatographic separation of the leaf extract resulted in the isolation of swainsonine (1), 2-epi-lentiginosine (2), calystegines B(1) (3), B(2) (4), B(3) (5), and C(1) (6), and N-methyl-trans-4-hydroxy-l-proline (7). The contents of 1 in the fresh leaves and flowers were 0.0029 and 0.0028%, respectively, whereas the contents of 1, 3, and 4 in the seeds were approximately 10 times higher than those in the leaves and flowers. Alkaloids 3, 4, and 6 showed a potent inhibitory activity toward rat lysosomal beta-glucosidase, with IC(50) values of 2.1, 0.75, and 0.84 microM, respectively, and alkaloid 5 was a moderate inhibitor of alpha- and beta-mannosidases. Although alkaloid 1 is known as a powerful inhibitor of lysosomal alpha-mannosidase (IC(50) = 0.02 microM), alkaloid 2, which has been thought to be an intermediate in the biosynthesis of 1, was also a potent inhibitor of alpha-mannosidase with an IC(50) value of 4.6 microM.  相似文献   
55.
Numerical experiments using a long-rage transport model of sulfur compounds were carried out to investigate influences of vertical distribution of sources on deposition fields in East Asia. Monthly dry depositions of SOx emitted from a source placed at the center of the domain were insensitive to the vertical distribution of the source, with increasing distance from the source. The depositions at the source grid strongly reflected the emission intensity in the lowest layer. The vertical distribution of sources affected the source-receptor relationships at receptors near locally large emissions but not so much at remote receptors. It was presented that long-rage transport was not influenced by the vertical distribution of sources, i.e., far sources may be treated as either area sources or elevated sources.  相似文献   
56.
In the present study, we tried to detect protozoan blood parasites from the liver or blood of 141 Japanese sika deer (Cervus nippon) in Iwate Prefecture of Japan by polymerase chain reaction. Approximately 500-bp amplicons were obtained in 76 (53.9%) of 141 samples by amplification for V4 hyper-variable regions of the 18S rRNA gene, and the amplicons were considered to be DNA of Theileria species. The complete nucleotide sequences (1701-bp) of the 18S rRNA gene were determined in 25 samples and were divided into 8 genotypes that were phylogenetically separated into two distinct lineages showing a monophyletic relation. The two lineages of Theileria were detected in different rates (12 and 88%) from sika deer in Iwate Prefecture.  相似文献   
57.
ABSTRACT: The effect of reward level (amount of food received in response to one trigger actuation) on the self-feeding activity of juvenile yellowtails was examined. Three groups of 10 juvenile yellowtails (mean bodyweight, 65.6 g) were allocated randomly to three 200 L cylindrical tanks set in the experiment room. Each tank was illuminated by overhead fluorescent lamps with a light : dark photoperiod regimen of 12 h : 12 h (light 06.00–18.00 hours). A rod-type tactile switch was used to activate the self-feeding device. Three levels of reward were set up by installing a different number of identical feeders for each group: one feeder for the low-reward group, three feeders for the medium-reward group and five feeders for the high-reward group. Each feeder delivered 3–7 pellets per actuation. Yellowtails in all groups showed a clearly diurnal feeding pattern that was synchronized to the given photoperiod. Average number of feeder actuations per day was highest (219/day) in the low-reward group. Second highest was the medium-reward group (116/day), and last was the high-reward group (67/day). The resultant average feed intake per day was 27.1 g/day in the low-reward group, 31.5 g/day in the medium-reward group and 28.4 g/day in the high-reward group. Thus, yellowtails appear to have the ability to regulate the amount of feed delivered daily by increasing the number of food demands when the reward is low and decreasing the number of food demands when the reward is high.  相似文献   
58.
Canine parentage testing based on microsatellite polymorphisms.   总被引:4,自引:0,他引:4  
To establish an accurate method for parentage testing in dogs, microsatellite DNA repeat length polymorphisms were examined. We selected twenty microsatellite markers reported previously and examined their application for parentage testing in Beagles and Labrador Retrievers. Heterozygosity (He), Polymorphism Information Content (PIC), the probabilities of Paternity Exclusion (PE) and the combined PE were calculated from allelic frequencies of the markers. All markers amplified by polymerase chain reactions were polymorphic and many markers showed high He and PIC in the both breeds. The final combined PEs in Beagles and Labrador Retrievers were 0.999994 and 0.999920, respectively. The results suggest that the twenty markers can be applied for routine parentage testing in dogs.  相似文献   
59.
Concern has been growing about the cardiac toxicity of antimalarial drugs. Artemisinin, a unique type of antimalarial drug originating from a Chinese medicinal plant, has minimal adverse effects, but it has been reported to inhibit delayed rectifier potassium current, a voltage-gated potassium current. However, no studies have been published concerning the effect of artemisinin on ligand-gated potassium currents. Therefore, in the present study, we examined the influence of artemisinin on the acetylcholine receptor-operated potassium current (IK.ACh), a ligand-gated potassium current, in guinea pig atrial myocytes using a patch clamp technique. Artemisinin (1 to 300 microM) inhibited I(K.ACh) induced by extracellular application of both carbachol (1 microM) and adenosine (10 microM) and that induced by intracellular loading of GTPgammaS (100 microM) in a concentration-dependent manner. Artemisinin inhibited carbachol-induced, adenosine-induced, and GTPgammaS-activated IK.ACh within almost the same concentration range. In left atria, artemisinin (1 to 100 microM) partially reversed the shortening of action potential duration induced by carbachol in a concentration-dependent manner. Carbachol-induced negative inotropic action in left atria was also inhibited by artemisinin (10 to 300 microM). In conclusion, we suggest that the anticholinergic action of artemisinin is mediated through inhibition of IK.ACh via inhibition of the muscarinic potassium channel and/or associated GTP-binding proteins.  相似文献   
60.
Purification and some properties of a Bacillus cereus mouse lethal toxin.   总被引:2,自引:0,他引:2  
A mouse lethal toxin (MLT) produced by Bacillus cereus isolated in vomiting-type food poisoning was purified by chromatography on DEAE-Sephadex A-25 followed by gel filtration on Sephadex G-75. Purified MLT possessed a molecular weight of 33,000-34,000. It showed mouse lethality and hemolytic (HL) activity on sheep and rabbit erythrocytes; the latter erythrocytes were more weakly hemolyzed than the former ones. However, fluid accumulation in mouse ligated intestinal loops was not induced by purified MLT at the highest concentration used. Both MLT and HL activities were stable at pH 6-9, during storage at -20 degrees C for 8 weeks, and resistant to papain, cholesterol, lecithin, and dithiothreitol treatments. Most activity was lost during storage at 4 degrees C or 25 degrees C for 2 weeks or upon treatment with trypsin, trypanblue, or ethanol. The activities were resistant to heating at 37 degrees C for 5 min, less resistant at 98 degrees C for 5 min, and sensitive at 60 degrees C for 5 min. It can be concluded from the results that MLT is different from the diarrheagenic toxin produced by B. cereus isolated in diarrheal-type food poisoning, but is similar to, if not identical, hemolysin II.  相似文献   
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