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1.
The association of tumor-associated antigen (TAA) on the proliferation of BLV-infected lymphoblastoid B-cell lines (BL2M3 and BL312) was investigated. Flow cytometric analysis of the expression of TAA with monoclonal antibody (mAb) c143 showed high expression of TAA on the surfaces of BL2M3 and BL312 cells. A large amount of TAA was found in the culture supernatant of BL2M3 and BL312 cells as well as in the lysates of BL2M3 and BL312 cells. Culture supernatant but not lysates of BL2M3 and BL312 cells promoted the growth of either BL2M3 cells or BL312 cells. Furthermore, this growth promoting activity in culture supernatants of BL2M3 and BL312 cells was inhibited in a dose-dependent manner when cultured with mAb c143. These results suggested that TAA may be involved in the growth factor-mediated cell growth of bovine B-lymphoblastoid cell lines expressing TAA on their cell surface.  相似文献   
2.
Lycopersicon esculentum cultivar Micro-Tom is a miniature tomato with many advantages for studies of the molecular biology and physiology of plants. To evaluate the suitability of Micro-Tom as a host plant for the study of pathogenesis, Micro-Tom plants were inoculated with 16 well-known fungal, bacterial, and viral pathogens of tomato. Athelia rolfsii, Botryotinia fuckeliana, Oidium sp., Phytophthora infestans, and Sclerotinia sclerotiorum caused typical symptoms and sporulated abundantly on Micro-Tom. Micro-Tom was resistant to Alternaria alternata, Corynespora cassiicola, and Fusarium oxysporum. When Micro-Tom was inoculated with 17 isolates of Ralstonia solanacearum, many isolates induced wilt symptoms. Agrobacterium tumefaciens also was pathogenic, causing crown galls on stem tissue after needle prick inoculation. In Micro-Tom sprayed with Pseudomonas syringae pv. tomato, P. s. pv. tabaci, or P. s. pv. glycinea, bacterial populations did not increase, and yellow lesions appeared only on leaves sprayed with P. s. pv. tomato. Tomato mosaic virus, Tomato aspermy virus, and Cucumber mosaic virus systemically infected Micro-Tom, which developed symptoms characteristic of other cultivars of tomato after infection with the respective virus. These results indicated that Micro-Tom was generally susceptible to most of the important tomato pathogens and developed typical symptoms, whereas certain pathogens were restricted by either hypersensitive resistance or nonhost resistance on Micro-Tom. Therefore, an assortment of Micro-Tom–pathogen systems should provide excellent models for studying the mechanism of susceptible and resistant interactions between plants and pathogens.  相似文献   
3.
Mammary tumors are the most common tumors in women and non-spayed female dogs. One of the reasons for mammary tumors is mutations of the tumor suppressor gene, BRCA2. BRCA2 participates in homologous recombination repair by interacting with the RAD51 recombinase. BRCA2 has two RAD51-binding domains, consisting of BRC repeats and the C-terminal RAD51-binding domain, respectively. Although several studies have addressed the function of the C-terminal RAD51-binding domain of human BRCA2, the amino acid sequences required for the RAD51-interaction activity remain unclear. In this study, the C-terminal RAD51-binding domains of canine and human BRCA2 were compared; the canine domain displayed a weaker interaction with RAD51. This difference was attributed to the C-terminal portion of the domain via a comparison between canine and human domains. Furthermore, peptides shorter than those previously reported displayed RAD51-interacting activity, and a core motif of this domain consisting of 25 amino acids was identified. Since a mutation (S3323N) was reported in the core motif of this domain, the effect of this mutation was evaluated. The mutant exhibited similar RAD51-binding activity as that of the wild-type protein, suggesting that the mutation was functionally neutral. These data suggested that the C-terminal portion of the BRCA2 C-terminal RAD51-binding domain influenced its RAD51-interaction activity, and a minimum core motif of 25 amino acids was identified in this domain. These data may help clarify BRCA2 function, as well as the tumorigenic effects of BRCA2 mutation.  相似文献   
4.
A simple method employing a commercially available canister was developed for the determination of mode of water absorption of rice flour samples. The samples prepared by four different grinding methods were used to analyze water absorption. The total amount of water in a flour sample was described by using an exponential model. Capacity and rate of water absorption of the samples were determined, and the relationship to baking quality of partially substituted rice bread was investigated. The water absorption was highly dependent on the method of grinding. Flours produced by wet jet‐milling of the grains, which absorbed a small amount of water at high speed, were most suitable for rice bread. The method was applicable to other food powders, provided that flour particles do not stick together or swell immediately upon contact with water.  相似文献   
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A 6-month-old barrow presented with lethargy, inappetence and dysstasia. At necropsy, multiple coalescing hemorrhagic foci were detected in the margins of the spleen. Gram-positive bacilli were isolated from the spleen, kidney, muscle and liver. Comparative 16S rDNA gene sequencing analysis of the isolates (TO16177) revealed that they would be the same species of unpublished Arcanobacterium species strain HJ57-14E (accession no. gi 18873551) (99.7% similarity based on a comparison of 675 bp). Histologic examination of the splenic tissue sections revealed extensive necrosis and inflammation, and gram-positive bacilli were discernible. Multifocal necrosis was also detected in the liver. Immunohistochemically, the isolates were cross-reacted with polyclonal antibodies against Arcanobacterium pyogenes and Actinomyces naeslundii, and the reaction was strong for the latter. Similar reactions were found in the suppurative lesions of the tonsil, and occasionally in the spleen and lymph nodes. The present results indicate that the unpublished Arcanobacterium species induced multiple organ failure accompanied by acute hemorrhagic necrotizing splenitis in this growing-finishing pig.  相似文献   
8.
IgE-reactive beef components were examined by an immunoblot analysis using a serum from a dog with food hypersensitivity against beef. The immunoblot analysis revealed a distinct band at approximately 66 kDa and a faint band at approximately 50 kDa. The immunoblot analysis for serum IgE reactivity to bovine serum albumin (BSA) also revealed a positive band at 66 kDa. Serum IgE reactivity to the 66-kDa protein of beef was diminished by pre-incubating the serum sample with BSA. Furthermore, a positive reaction to BSA was detected in intradermal testing in the dog. These results clearly indicated that BSA was an IgE-reactive beef component in the dog with food hypersensitivity against beef.  相似文献   
9.
Heated and hydrated naturally occurring dolomite showed very strong antiviral activity. Infectivity of avian and human influenza, avian infectious bronchitis (coronavirus), Newcastle disease (paramyxovirus) and avian laryngotracheitis (herpesvirus) viruses dropped at least 1,000 fold following contact with the dolomite for five minutes at 4 degrees C. Dolomite is expected to be useful to inhibit the incidence of emerging and re-emerging infectious diseases.  相似文献   
10.
Based on the respiratory quinone profile, changes in the structure of microbial communities in the soil samples from Nagoya University Farm were monitored after the treatment with 1% of a mixture of glucose and peptone. Samples of two soils differing in the fertilization history were examined: CF-soil with the application of only chemical fertilizers and FYM-soil with the application of only farmyard manure at a high rate. In the CF-soil, the amount of water-soluble organic carbon (WOC), indicator of the mixture of glucose and peptone, decreased to the original level after 14 d. After 7 d, the soil pH reached the maximum level, then decreased gradually. Changes in the inorganic nitrogen levels in the water extract also reflected the 14-d period of mineralization. The amount of respiratory quinones reached maximum levels after 7 d and gradually decreased, reflecting the changes in the microbial biomass. The quinone composition significantly changed during the 14-d period and returned to a profile similar to the original one after 28 d. Diversity of quinones significantly decreased during the 14-d period due to the predominance of ubiquinone with 9 isoprenoid units. In the FYM-soil, the amount of WOC decreased to the original level after 1 d, and the pH and inorganic nitrogen levels in the water extract reflected the one-day mineralization period, and nitrification started after 3 d. Although the amount of quinones indicated an increase in the microbial biomass for 14 d, the quinone composition did not change. These findings suggested that long-term application of farmyard manure resulted in stable microbial communities in response to the incorporation of organic matter in soil.  相似文献   
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