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Molecule possessing ankyrin-repeats induced by lipopolysaccharide (MAIL) is a nuclear IkappaB protein that is also known as interleukin-1-inducible nuclear ankyrin repeat protein and inhibitor of nuclear factor kappaBzeta (IkappaBzeta). We previously observed that MAIL-deficient mice were affected by atopic dermatitis-like skin lesions and demonstrated the importance of MAIL in the skin. In this study, we investigated MAIL expression in mouse keratinocytes. MAIL mRNA was constitutively expressed in the skin epidermis. MAIL expression was also confirmed in primary keratinocytes and the PAM212 keratinocyte cell line. The inhibitors of nuclear factor kappaB (NF-kappaB)-Bay11-7082 and the IkappaBalphaM supersuppressor-considerably downregulated MAIL expression in the keratinocytes. Immunoreactivity for NF-kappaB components was localized in the cytoplasm and nucleus of normal unstimulated keratinocytes. The expression level of MAIL in the skin did not change following lipopolysaccharide (LPS) administration to mice. Interestingly, in accordance with the in vivo findings, the MAIL expression level did not change following LPS stimulation even in primary keratinocytes; however, MAIL expression was strongly increased by interleukin-1 stimulation. These results collectively suggest that the constitutive expression of MAIL in keratinocytes is controlled, at least in part, by NF-kappaB and that there may be LPS-specific repressive mechanisms that inhibit MAIL induction.  相似文献   
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In this study, we showed that feeding rats the organic extract of scallop shells (scallop shell extract) caused a decrease in the weights of white adipose tissues in rats fed a high-fat diet. In addition, the cholesterol concentration in the serum of rats that received a diet containing scallop shell extract was significantly lower than that in the serum of rats on the control diet. Feeding this scallop shell extract to rats increased the fecal weight as well as the fecal excretion of bile acids. The amino acid composition of the feces from rats fed the scallop shell extract was different from that of feces from rats fed the control diet, and treatment of the extract with pepsin and pancreatin identified a protein with a molecular weight of 90 kDa (90-kDa protein) as one of the indigestible proteins. Interestingly the 90-kDa protein was found to be identical to a free radical-scavenging protein we previously identified and showed the ability to bind bile acids. These results suggest that indigestible proteins (resistant proteins) in the scallop shell extract, including the 90-kDa protein, inhibit the absorption of bile acid by binding to it and cause increased excretion of fecal bile acid, which subsequently may decrease the serum cholesterol level.  相似文献   
4.
We have previously reported that the scallop shell extract possesses free radical scavenging activity. In this study, we isolated a glycoprotein with a molecular weight of approximately 90 kDa (named 90-kDa protein) which showed 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide anion radical scavenging, reducing, and ferrous ion-chelating activities. Amino acid composition analysis showed that the 90-kDa protein was rich in Asx (Asp or Asn), Ser and Gly residues. A BLAST search of partial amino acid sequences determined by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry revealed that the 90-kDa protein is a novel protein. The 90-kDa protein is a yellow protein that contains fluorescent substances. To the best of our knowledge, this is the first report of a radical scavenging protein from the scallop shell.  相似文献   
5.
冰藏鲢的鲜度变化对其鱼糜凝胶作用的影响   总被引:13,自引:0,他引:13  
通过比较不同冰藏时间的鲢所制鱼糜在各种加热温度下的凝胶化和凝胶劣化的特性,考察了鲢的鲜度变化与鱼糜凝胶作用能力的关系。实验结果表明:冰藏0 ̄9天鲢鱼糜,在30℃低温一段加热时凝胶的形成与链鲜度关系不大;85℃一段加热时,凝胶化能力随鲜度下降而降低;30 ̄85℃二段加热与30℃一段加热相比,两者凝胶破断强度之间的差值随鲢鲜度的下降而减小;60℃加热条件下,凝胶劣化程度随原料鲜度下降而明显加剧。据此可见:鲜度对鲢鱼糜凝胶作用能力的影响主要表现在凝胶劣化方面。85℃高温一段加热和30 ̄85℃二段加热的凝胶强度之所以受鲜度下降而影响,都是由于加热时经过了易劣化的60℃温度区所致。从总体上看,鲢肉蛋白质在冰藏条件下较为稳定,保持较强的凝胶化能力。  相似文献   
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7.
Age-related changes in bone mineral density (BMD), cross-sectional area and strength strain index (SSI) of the long bones in the limbs and first lumbar vertebra of male Wistar rats were measured by a peripheral quantitative computed tomography (pQCT) method. One hundred and ten rats aged 2-30 months were used. The results indicate that the total (cortical + trabecular), cortical and trabecular BMD values of the metaphysis and cortical BMD values of the diaphysis in the long bones varied for each bone and differed from those of the first lumbar vertebra. The total BMD of long bones showed high values at 6-21 months and then decreased, but these did not always coincide with cortical and trabecular BMD. The values of SSI in the long bones varied. The values of total and cortical BMD and SSI of lumbar vertebra increased for 6-12 months and then decreased, but the trabecular BMD increased after 12 months. The total area in both the long bones and the first lumbar vertebra increased with the decrease in cortical area and the increase in the trabecular area with increasing age. It was concluded that age-related changes in bones, similar to those observed in humans, could be observed in some bones and parameters, although the age in rats when the so-called peak bone mass appears in the whole skeleton could not be clearly determined.  相似文献   
8.
The correlation between the serum hydroxyproline concentration and serum activity levels of TRAP and BALP was examined in 41 cows. The correlated coefficient (r) was 0.6391 for TRAP and 0.3147 for BALP, respectively. Judging from the significant correlation to the serum hydroxyproline concentration, serum TRAP activity is an index for bone metabolism in cows. Serum TRAP activity was therefore measured in 205 healthy cows (2-9 years old) in order to observe the changes in bone resorption with aging and milk production. TRAP levels differed slightly between group A (< or =4 yrs) and B (5 yrs< or =) at the same stage of lactation. The activity levels rose slightly at the height of lactation stage and during the dry stage.  相似文献   
9.
In order to confirm the in vivo effectiveness of anti- feline herpesvirus type 1 (FHV-1) mouse-cat chimeric antibody (FJH2), and anti-feline calicivirus (FCV) mouse-cat chimeric antibody (F1D7), cats that had been experimentally infected with FHV-1 or FCV were administered intravenously with the chimeric antibodies, and observed for clinical manifestations. The symptoms due to FHV-1 or FCV infection in the cats administered FJH2 or F1D7 were obviously decreased when compared with those of the non-administered control cats. From these results, it was confirmed that both FJH2 and F1D7 were effective at reducing the appearance of symptoms due to FHV-1 and FCV infection, respectively.  相似文献   
10.
The purpose of this study was to examine: 1) whether caffeine in the fertilization medium under mineral oil is essential for bovine in vitro fertilization by fully capacitated spermatozoa, 2) the minimum concentration of caffeine that shows an adverse effect on the motility of preincubated spermatozoa. Cumulus-oocyte complexes with heterogeneous-appearing ooplasm were matured in in vitro culture for 24 h and used for insemination. The fertilization rates of the preincubated spermatozoa introduced into the fertilization medium containing 0 mM or 5 mM caffeine were examined. The fertilization rate of the spermatozoa introduced into the medium without caffeine (final concentration of caffeine at fertilization was 0.27-0.35 mM) was significantly higher than that in the medium with 5 mM caffeine (82.4% vs 55.2%, P<0.05). When the final concentration of caffeine at fertilization was reduced ten-fold (0.02-0.03 mM), the fertilization rate was not significantly improved (86.0%). The motility of the preincubated spermatozoa introduced into the fertilization medium containing 0-5 mM caffeine was examined. The sperm motility in the fertilization medium without caffeine was significantly higher than that in the fertilization medium with more than 2 mM caffeine. These results indicate that caffeine in the fertilization medium is not essential for bovine in vitro fertilization by fully capacitated spermatozoa, and that more than 2 mM caffeine has an adverse effect on preincubated (capacitated) sperm motility.  相似文献   
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