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31.
The effects of an egg-yolk-derived sialyloligosaccharide (YDS), asialo-YDS, and a sialylglycopeptide of YDS (SGP) on bacterial adhesion to intestinal epithelial cells and on Salmonella infection in BALB/c mice were examined. YDS, its derivative asialo-YDS, and SGP strongly inhibited the binding of Salmonella enteritidis but not E. coli K-88 to a human epithelial cell line, Caco-2. In a Salmonella infection experiment using BALB/c mice, oral administration of these reagents effectively prevented the bacteria from proliferating in spleen, as well as preventing lethality. An experiment using radioactive SGP orally administered to mice revealed that the compound was absorbed from the intestine into blood and eliminated via urine within 8 h. However, these reagents did not influence the production of TNF-alpha or NO. in culture macrophages. The results suggest that they inhibit Salmonella infection not by activating macrophages but by inhibiting the entry of bacteria through the gut, suggesting that YDS and its derivatives are useful for preventing Salmonella infection when ingested continuously.  相似文献   
32.
Regulatory elements in the promoter of phenylalanine ammonia-lyase gene 1 of pea (PSPAL1) in response to nonpathogenic attack were identified by in vivo footprinting analysis. The footprints determined AC-rich sequences, Box-I and Box-II, that were conserved at similar positions in the phenylpropanoid gene promoters from several plants. To reveal the functions of the AC-rich sequence in nonpathogen-responsiveness, we constructed Box-I-deletion PSPAL1 promoter (dB-1) with GUS reporter gene and transformed it into tobacco plant. The dB-1 had reduced basal expression and a complete loss of nonpathogen-responsiveness. These results indicate the essentiality of Box-I for PSPAL1 activation induced by nonpathogenic attack. Received 27 October 1999/ Accepted in revised form 25 November 1999  相似文献   
33.
A series of carotenoids with 19- or 19'-hexanoyloxy moieties, 19'-hexanoyloxyfucoxanthin (1), 19'-hexanoyloxyfucoxanthinol (2), 19'-hexanoyloxyhalocynthiaxanthin (3), 19-hexanoyloxycrassostreaxanthin A (4), 19-hexanoyloxymytiloxanthin (5), and 19-hexanoyloxyallenicmytiloxanthin (6) were isolated from the edible part of the sea mussel, Mytilus galloprovincialis, grown in the Black Sea, Ukraine. Among them, 3, 4, and 6 were new compounds. These structures were charcterized by UV-vis, fast atom bombardment mass spectrometry, circular dichroism, and (1)H NMR spectroscopic data. They were assumed to be metabolites of 19'-hexanoyloxyfucoxanthin (1).  相似文献   
34.
The objective of this article is to compare feed cost, palatability and environmental impacts among feeding systems of high concentrate (HC), high hay (HH) and grass‐only‐fed (Gof) groups. Feed cost was the sum of costs paid for feed intake times the price of feed per kilogram. Palatability was measured by a panel taste test using HH and Gof beef and analyzed for differences. Environmental impacts were calculated based on 1 kg of Japanese beef yield of CO2 equivalents (eq) and animal end weights at each feeding stage. Results showed that the HH and Gof feeding systems could significantly reduce feed costs by approximately 60% and 78%, respectively, from the HC. In the panel taste test, 50% and 47.50% of panelists indicated that HH beef was ‘extremely delicious’ and ‘acceptable,’ respectively, while 15% indicated that Gof beef was ‘extremely delicious’; 62.50% indicated that Gof beef was ‘acceptable.’ Environmental impacts of each feeding system in terms of CO2 equivalents (eq) were 9.32, 6.10 and 2.04 tonnes of eq for the HC, HH and Gof, respectively. The HH was an economical system that produced moderate impacts on the environment and had impressive taste.  相似文献   
35.
ABSTRACT:   For pearl production, pearl oyster seeds from foreign pearl oysters as well as hybrids between native and such foreign pearl oysters are produced in Japanese hatcheries. However, it is very difficult to identify these pearl oysters and hybrids based on morphological measurements. Thus, a molecular identification method for distinguishing Atlantic pearl oysters Pinctada imbricata from the Indian-Pacific pearl oyster group including P. martensii and P. fucata , was developed. The polymerase chain reaction (PCR) products of the partial intergenic spacer (IGS) of nuclear ribosomal RNA (rRNA) genes exhibited length polymorphism between P. imbricata (590 bp) and the other two species (427 bp). The restriction fragment length polymorphism analysis of the PCR products (PCR-RFLP) cleaved with Mse  I observed in the IGS of nuclear rRNA genes also gave different profiles between P. imbricata and the other two species. The difference in PCR-RFLP using Alu  I was also detected in the mitochondrial 16S rRNA gene regions between P. imbricata and the other two species. Thus, the method developed enables the distinction of P. imbricata from P. martensii and P. fucata .  相似文献   
36.
A 10-year-old cat with the paresis of hind limbs was initially diagnosed as a hypertrophic cardiomyopathy followed by acute thromboembolism of caudal abdominal aorta from the findings of the medical examinations. However, this case was proved to be an chronic myocardial infarction due to arteriosclerosis of coronary arteries by the pathologic diagnosis. In the left ventricular, the hypertrophy and the narrowing were slight, and a coagulative infarction was seen obviously. The intramural coronary arteriosclerosis showed thickening of the wall due to medial hyperplasia by fibrosis, and arterial stenosis. Myocardial infarction and arteriosclerosis are scarcely any reports of these lesions in cats. This case is valuable for an extremely rare case of myocardial infarction in the cat.  相似文献   
37.
Chemokines are important regulators of the selective recruitment of inflammatory cells into sites of allergic inflammation. Since canine atopic dermatitis (AD) shares many clinical features of human AD, patterns of chemokine production in dogs may also be similar with those in humans. The aim of this study was to examine mRNA expression of CCL27 and CCL28 in lesional skin of dogs with AD to demonstrate similarity of chemokine production with human counterparts. RNA was extracted from skin biopsy specimens of 12 dogs with AD. The mRNA expression of CC chemokines (CCL4, CCL19, CCL20, CCL21, CCL24, CCL27 and CCL28) was analyzed by quantitative real-time PCR and was compared between lesional and non-lesional skin. Seven types of chemokines examined were constitutively expressed in both lesional and non-lesional skin. It was found that mRNA expression levels of CCL27 and CCL28 among the chemokines were significantly different between lesional and non-lesional skin (P<0.05). Expression level of CCL27 mRNA in lesional skin was significantly lower than that in non-lesional skin. On the other hand, CCL28 mRNA expression in lesional skin was found to be higher than that in non-lesional skin. These results suggest that CCL28 but not CCL27 may play important roles in immunopathogenesis of canine AD, indicating that experimental canine study may provide additional information that can be extrapolated to human AD.  相似文献   
38.
Phytotoxic activity of several middle-chain fatty acids, especially pelargonic acid (C9 acid) was investigated. C9–C11 acids caused strong non-selective damage to plants such as crabgrass, cucumber, velvetleaf, and tobacco, while C6 and C14 fatty acids had almost no activity. Middle-chain fatty acids caused a strong and rapid electrolyte leakage. They reached highest conductivity in 3 h in the case of cucumber cotyledons. Middle-chain fatty acids caused a decrease of the amount of polar lipids, particularly MGDG and PG, and chlorophylls. They also caused an increase of free fatty acids in 24 h after treatment. These results suggested that middle-chain fatty acids caused severe damage to cell membranes and thylakoid membranes of treated leaves. C6 volatile compounds such as cis-3-hexenal, trans-2-hexenal, and cis-3-hexenol were generated in less than 1 h after spraying pelargonic acid to tobacco leaves. The application of pelargonic acid was thought to be the trigger for linolenic acid degradation in the thylakoid membranes.  相似文献   
39.
An increase in size of sika deer populations has caused severe damage to forest vegetation in many regions of Japan. In a Natural World Heritage area on the western part of Yakushima Island, existing high densities of deer are thought to be increasing, but the impact of deer on forest vegetation has not been estimated. Roadside censuses of deer between 1988 and 2006 showed that encounter rates are continuing to increase. Long-term monitoring of individual tree saplings in a 0.13 ha area of the forest between 1992 and 2005 showed that many saplings still remain despite increases in sika deer density. However, differences in growth and mortality rates of preferred, neutral (neither preferred nor avoided) and avoided sika deer food species varied over time. As a group, preferred species continuously had a low growth rate, while their mortality rate increased through time. The growth rates of the neutral and avoided groups decreased especially in the second half of our study period at the same time that their mortality rates increased. These data suggest that in spite of food species preference, direct feeding pressures as well as indirect physical effects by increasing sika deer density are affecting growth and mortality of tree saplings. Clearly, it is difficult to predict how plant communities will respond to possible continued sika deer population growth, and it is therefore important to continue monitoring these forest communities in the interest of preserving the unique ecosystems on Yakushima Island.  相似文献   
40.
Cryopreservation of boar spermatozoa offers an effective means of long‐term storage of important genetic material. Many researchers have investigated how to improve reproductive performance by artificial insemination (AI) using cryopreserved boar spermatozoa. Recently, we and other groups reported that high conception rates (70–80%) can be achieved by AI with frozen‐thawed boar spermatozoa using a modified temperature program during freezing, or a novel cryopreservation extender to improve sperm quality (including sperm survivability, motility, membrane status and fertilization ability) after thawing, or a novel sperm infusion method, deep intra uterine insemination. However, these techniques have not yet been used for commercial pig production. The variation in sperm freezability among boars or among ejaculations in an identical boar is one of the main reasons for this problem. In our previous study, it was revealed that some components of seminal plasma have a negative effect on the freezability of boar sperm. One of these factors is bacteria‐released endotoxin (lipopolysaccharide: LPS). LPS binds to Toll‐like receptor‐4 (TLR‐4) expressed on the sperm surface, resulting in induction of apoptosis. On the other hand, seminal plasma suppresses cryo‐capacitation induced by thawing stress. On the basis of these findings, we designed a novel protocol of AI using frozen‐thawed boar sperm.  相似文献   
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