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51.
Fisheries Science - Two sediment cores were collected from two sites in Nagatsura-Ura Lagoon, the mouth of which was destroyed in the 2011 Tohoku-oki tsunami. Although sediment conditions differed...  相似文献   
52.
Food colorants including rose bengal, erythrosine B, phloxine B and cochineal extracts were added to Alaska pollack Theragra chalcogramma surimi which was previously added with methyl linoleate (MeLe) or ethyl eicosapentaenoate (EPA Et). All the surimi were exposed to a 100-watt light tungsten bulb (4500 lux) in a cold room at 5°C. Four isomeric hydroperoxides, including 13-cis, trans-, 13-trans, trans-, 9-trans,cis- and 9-trans,trans-MeLe hydroperoxides, were generated by oxidation of MeLe added to surimi with and without cochineal extracts after exposure to light for several hours. For the surimi containing rose bengal, erythrosine B and phloxine B, extracted lipids contained not only the above four hydroperoxide isomers but also 12-cis,trans-as well as 10-trans,cis- MeLe hydroperoxides. EPA Et added to surimi which contained rose bengal, erythrosine B and phloxine B generated characteristic isomeric hydroperoxides, including 6-cis,trans- and 17-cis,trans-EPA Et hydroperoxides due to 1O2 mediated oxidation. The pro-oxidative potentials of four food colorants in surimi against added EPA Et or MeLe increased as the order of cochineal extracts < phloxine B<erythrosine B<rose bengal. These results clearly demonstrated that the addition of certain food colorants to surimi accelerated 1O2 mediated lipid oxidation to result in the generation of characteristic hydroperoxide isomers.  相似文献   
53.
We examined in vivo efficiency of a gelatin film sheet with epidermal growth factor (EGF) for a novel therapeutic device for cutaneous wound repair. NIH3T3 fibroblasts and PAM212 keratinocytes proliferated when the cells were incubated with the homogenate of EGF containing gelatin sheets, indicating that the gelatin sheet retained biologic activity of EGF in the process of sheet formation. To evaluate therapeutic effects, the EGF containing gelatin sheets or control sheets were applied onto partial-thickness skin wounds made on dorsa of hairless dogs. Wound closure in wounds treated with EGF containing gelatin sheets was accelerated when compared to that of wounds treated with control sheets, exhibiting earlier reepithelialization of the epidermis and highly regulated repair of extracellular matrix in the dermis. Therefore, we concluded that the gelatin film is a useful material to keep EGF stable and the EGF containing sheet has the ability to become an efficient therapeutic agent for superficial or deep partial-thickness wounds in the skin.  相似文献   
54.
ABSTRACT Determining the population density of the spinach wilt pathogen Fusarium oxysporum f. sp. spinaciae in soil with conventional Fusarium-selective media is quite difficult because nonpathogenic strains of F. oxysporum also grow on those media and are indistinguishable from the pathogen. Therefore, a nitrate-nonutilizing (nit) mutant of the pathogen and corresponding selective media were tested in an experimental approach to determine the population density of the pathogen. Colony forming units of the pathogen were countable after soil-dilution plating onto nit mutant-selective media MMCPA, CMP, and CGMBP. Colony forming units of wild-type Fusarium spp. were countable using a wildtype Fusarium-selective medium, GMBP. By combining nit mutant- and wild-type-selective media, the population densities of pathogenic and nonpathogenic F. oxysporum in the same soil could be measured selectively. This method was useful in studying population dynamics of the pathogen after different soil treatments. Soil disinfested with hot water or chloropicrin was amended with the nit mutant pathogen, and subsequent changes in population densities of the pathogen were compared with those in nontreated field soil. The pathogen rapidly proliferated in disinfested soil and wilt developed faster than in nontreated soil. When a nonpathogenic isolate of F. oxysporum was added at high density to sterilized soil prior to the pathogen, growth of the pathogen was greatly suppressed. Nonpathogenic F. oxysporum could not, however, reduce the density of preexisting pathogen.  相似文献   
55.
In the plant cell wall of Pisum sativum seedlings, we found an NTPase (E.C. 3.6.1.5.) with ATP-hydrolyzing activity that was regulated by an elicitor and suppressors of defense from pea pathogen Mycosphaerella pinodes. The ATPase-rich fraction was purified from pea cell walls by NaCl solubilization, ammonium sulfate precipitation, and chromatography with an ATP-conjugated agarose column and an anion-exchange column. The specific activity of the final ATPase-rich fraction increased 600-fold over that of the initial NaCl-solubilized fraction. The purified ATPase-rich fraction also had peroxidase activity and generated superoxide, both of which were regulated by the M. pinodes elicitor and suppressor (supprescins). Active staining and Western blot analysis also showed that the ATPase was copurified along with peroxidases. In this fraction, a biotinylated elicitor and the supprescins were bound primarily and specifically to ca. 55-kDa protein (CWP-55) with an N-terminal amino acid sequence of QEEISSYAVVFDA. The cDNA clone of CWP-55 contained five ACR domains, which are conserved in the apyrases (NTPases), and the protein is identical to a pea NTPase cDNA (GenBank accession AB071369). Based on these results, we discuss a role for the plant cell wall in recognizing exogenous signal molecules.  相似文献   
56.
The pathogenicity of serotype 1 group I avian adenovirus (GIAAV) strains isolated from gizzard erosions for 1-wk-old specific-pathogen-free (SPF) chickens was investigated. In Experiment 1, SPF chickens inoculated orally with a serotype 1 strain (Tokushima2000/GE) of GIAAV isolated from gizzard erosion in broilers were euthanatized and necropsied from 3 to 12 days after inoculation. Clinically, there were no significant signs in the chickens inoculated with Tokushima strain. The gizzards were found macroscopically to be dilated with liquefied contents. The koilin layer of the gizzard exhibited multifocal white lesions with occasional erosions. Gross lesions of the koilin layer (white foci and erosion) appeared at 3 days after inoculation and persisted until 12 days after inoculation. The gross lesions were most severe at 9 days after inoculation. Histologically, multifocal degeneration, necrosis, and loss of the glandular epithelial cells with intranuclear inclusions, liquefactive change of koilin substance, and erosive lesions of koilin layers and surface epithelium of the gizzards were observed. Macrophages increased in the focal areas of the lamina propriabelow the liquefactive koilin substances. Immunohistochemically, intranudear inclusions were positive against GIAAV antigen. Histologic lesions of gizzards were most severe at 7 and 9 days after inoculation, but the frequency of intranuclear inclusions was greatest at 5 days after inoculation. In Experiment 2, the pathogenicities of four strains of serotype 1 GIAAV for 1-wk-old SPF chickens were compared. Three strains isolated from gizzard erosion had similar pathogenicities but one strain from a normal chicken was not pathogenic for chickens. These results suggest that gizzard erosions by serotype 1 GIAAV infection may occur in broiler chickens in Japan.  相似文献   
57.
Periodic growth incremental lines are found universally in dental hard tissues. This periodicity theoretically allows for estimation of age, even in days, which would be useful in studies of wild animals. In the present study, enamel and dentin increments of the sika deer (Cervus nippon) were observed in ground sections with a polarized light microscope, and their periodicity was examined by the use of a chronological labeling method with fluorochromes. Enamel increments occurred at a mean interval of 10.6 (SD=1.5) microm, and mean spacing of dentin increments was 17.3 (SD=1.8) microm. Fluorochromic marking revealed that incremental lines form each day in enamel and almost every second day in dentin. The fluorescence-labeled lines suggest that enamel formation of the first molar is complete by the age of 5 months. Due to its longer interval of incremental lines and longer term of formation, we conclude that dentin is more suitable than enamel for day-age estimation in sika deer. Experimental confirmation of incremental growth periodicity in various species can improve the reliability of use of tooth increments for age estimation and life history reconstruction.  相似文献   
58.
The present study was undertaken to investigate whether withdrawal of estrogen and progesterone (EP-withdrawal) stimulates prostaglandin F2alpha (PGF2alpha) production through oxygen radical (ROS)-induced NF-kappaB activation in human endometrial stromal cells (ESC). To study the EP-withdrawal, ESC that had been treated with estradiol (E, 10(-8) M) and medroxyprogesterone acetate (MPA, 10(-6) M) for 12 days were then incubated with or without E+MPA for a further 11 days. PGF2alpha concentrations in the medium and cyclooxygenase-2 (COX-2) mRNA levels were significantly increased after EP-withdrawal, while they were unchanged by the continuous treatment with E+MPA. When ESC were incubated with N-acetyl-L-cysteine (Nac, 50 mM), an antioxidant, during EP-withdrawal, Nac blocked the increases in PGF2alpha production and COX-2 mRNA expression caused by EP-withdrawal. Next, we examined whether ROS generated in response to EP-withdrawal acted through NF-kappaB activation. Electrophoretic mobility shift assay revealed that EP-withdrawal caused marked increases in NF-kappaB DNA binding activity, which was completely suppressed by Nac. Furthermore, when ESC were incubated with MG132 (3 microM), which inhibits NF-kappaB activation, during EP-withdrawal, MG132 blocked the increases in PGF2alpha production and COX-2 mRNA expression caused by EP-withdrawal. In conclusion, EP-withdrawal stimulates COX-2 expression and PGF2alpha production through ROS-induced NF-kappaB activation, suggesting a possible mechanism for menstruation.  相似文献   
59.
The quality of Tombul (Round) hazelnut, grown in the Giresun province of Turkey, was determined by measuring proximate composition, minerals, vitamins, dietary fiber, amino acids, and taste active components (free amino acids, sugars, and organic acids). Fat was the predominant component in Tombul hazelnut (approximately 61%). The major minerals were potassium, phosphorus, calcium, magnesium, and selenium. Hazelnut was also found to serve as an excellent source of vitamin E (24 mg/100 g) and a good source of water soluble (B complex) vitamins and dietary fiber. The major amino acids were glutamic acid, arginine, and aspartic acid. The three nonessential amino acids and the essential amino acids contributed 44.9 and 30.9% to the total amino acids present, respectively, while lysine and tryptophan were the limiting amino acids in Tombul hazelnut. Twenty-one free amino acids, six sugars, and six organic acids were positively identified; among these, arginine, sucrose, and malic acid predominated, respectively. These taste active components may play a significant role in the taste and flavor characteristics of hazelnut. Thus, the present results suggest that Tombul hazelnut serves as a good source of vital nutrients and taste active components.  相似文献   
60.
Summary A maize plant resistant to 5-methyltrytophan (5MT) was selected from M2 seeds (Zea mays L. Danggin, inbred line) originating from ears treated with ethylmethane sulfonate (0.2%) at 6 hr after self-pollination. Genetic analysis of the progeny of plants selected from a medium containing 50 ppm 5MT showed that 5MT resistance was inherited as a single dominant nuclear gene. This resistance was also expressed in callus and seedling. Analysis of the free amino acids in kernels and calli showed that homozygous resistant plants (MR1) contained higher levels of total free amino acids than sensitive plants and calli. In particular, the their kernels the levels of tryptophan, threonine and serine were, respectively, 4.5, 5.9 and 6.3 times higher than those of the sensitive plants. From the results, it may be expected that mutants resistant to amino acid anologs will be useful not only for studying amino acid biosynthesis but also for improving the nutritional quality of maize.Abbreviations EMS Ethylmethane sulfonate - 5MT 5-methyltryptophan - 2,4-D 2-4-dichlorophenoxyacetic acid  相似文献   
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