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71.
Histochemical analysis of macrophage migration inhibitory factor in psoriasis vulgaris 总被引:1,自引:1,他引:0
Shimizu T Nishihira J Mizue Y Nakamura H Abe R Watanabe H Ishibashi T Shimizu H 《Histochemistry and cell biology》2002,118(3):251-257
Psoriasis is a persistent cutaneous disease characterized by skin inflammation and infiltration of immunocytes such as lymphocytes and monocytes/macrophages, concomitant with abnormal epidermal hyperproliferation. We previously showed that the serum level of macrophage migration inhibitory factor (MIF) and its production by peripheral blood mononuclear cells of patients with psoriasis were closely correlated with the severity of clinical symptoms; however, the precise role of MIF in psoriatic epidermis remains to be clarified. The current study was carried out to elucidate the possible involvement of MIF in psoriasis, using immunohistochemistry and in situ hybridization. In contrast to elevated serum MIF in psoriasis, MIF-positive staining in the lesional psoriatic epidermis was significantly decreased, as demonstrated by immunohistochemical analysis using an anti-MIF antibody. Consistent with this finding, we found, by in situ hybridization, that MIF mRNA concomitantly decreased in the psoriatic lesions. Although the reason for the different MIF levels in the psoriatic epidermis and in the circulation remains unknown, it is hypothesized that MIF, a potential growth factor, might be decreased in psoriatic lesions to counterregulate the abnormal epidermal proliferation caused by dysregulation of cytokines and growth factors. 相似文献
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Intracytoplasmic sperm injection is more efficient than in vitro fertilization for generating mouse embryos from cryopreserved spermatozoa 总被引:3,自引:0,他引:3
Efficient and dependable mouse cryopreservation methods are urgently needed because the production of mice with transgenes and disrupted and mutant genes is now commonplace. Preservation of these unique genomes provides an essential safeguard for future research. Unfortunately, mouse spermatozoa appear more vulnerable to freezing than other species, e.g., bovine and human. In this study, we examined the efficiency of intracytoplasmic sperm injection (ICSI) and in vitro fertilization (IVF) in generating embryos from mouse spermatozoa frozen with 18% raffinose and 3% skim milk for cryoprotection. A comparison was made between the inbred strain C57BL/6J, commonly used in mutagenic and transgenic studies, and a hybrid strain B6D2F1 (C57BL/6J x DBA/2J). C57BL/6J spermatozoa are known to be more sensitive to freezing than B6D2F1. Fertilization of oocytes after IVF was significantly lower with C57BL/6J spermatozoa when compared with B6D2F1 spermatozoa for both fresh and frozen spermatozoa (fresh, 89 vs. 55%; frozen, 56 vs. 9%). Freezing also reduced the fertility of B6D2F1 spermatozoa (89 vs. 56%). Fertilization improved dramatically after ICSI with fresh and frozen C57BL/6J spermatozoa (90 and 85%) and also with frozen B6D2F1 spermatozoa (87%). The development of two-cell embryos to the blastocyst stage was lower for C57BL/6J than B6D2F1 (42-61% and 84-98%) in all treatments but similar for embryos within each strain. The normality of chromosomes from fresh and frozen spermatozoa was assessed in oocytes prior to first cleavage. The majority of oocytes had normal chromosomes after IVF (98-100%) and ICSI (87-95%), indicating that chromosomal abnormalities were not responsible for the poorer development in vitro of C57BL/6J embryos. In conclusion, our data show that ICSI is a more efficient and effective technique than IVF for generating embryos from frozen spermatozoa. More important, ICSI is especially valuable for strains where IVF with fresh spermatozoa produces few or no embryos. 相似文献
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T.P. Melia's chemical kinetics study of the disproportionation of nitric oxide (NO), 3NO →NO2 + N2O , (Melia, T.P. (1965) J. Inorg. Nucl. Chem., 27, 95-98), which is the most quoted quantitative investigation presently available, revealed a rather strong dependence of the effective rate constant, Kk ', of Melia's third-order rate law,- d[NO]/d t = Kk'[NO]3, on the initial pressure of NO. In order to estimate extent of accumulation of NO2 and N2O as a function of time by integration of the rate law, we have evaluated the dependence of the effective rate constant as a function of pressure and thus as a function of time on the basis of the non-ideality of NO gas. Although our approach is crude in that the non-idealities of NO2 and N2O and other NOx products and a probable deviation of the gas mixture from the Dalton's law have not been considered, it provides a means for approximately estimating the rate of accumulation of NO2 and N2O based on Melia's data. According to these calculations, the extent of the disproportionation is generally negligible at low initial pressures, e.g. 5 atm or less, while at 200 atm, the mole fractions of NO2 and N2O can become as high as 12-13% only after 10 days. These values are alarmingly high for handling pressured NO- in N2-mixture in either research or clinical settings. This information must be borne in mind when compressed NO in commercial cylinders is employed in high precision experiments. Disproportionation of NO under pressure also deserves attention in inhalation of low doses of NO in the treatment of diseases characterized by pulmonary hypertension and hypoxemia. 相似文献
77.
Isolation of Paenibacillus illinoisensis that produces cyclodextrin glucanotransferase resistant to organic solvents 总被引:1,自引:0,他引:1
A bacterium that secreted cyclodextrin glucanotransferase (CGTase) in a medium overlaid with n-hexane was isolated and identified as Paenibacillus illinoisensis strain ST-12 K. The CGTase of the strain was purified from the culture supernatant. The molecular mass was 70 kDa. The enzyme was stable at pH 6 to 10 and active at pH 5.0 to 8.0. The optimum temperature at pH 7.0 was 65 degrees C in the presence of 5 mM CaCl2. The enzyme produced mainly beta-cyclodextrin. The total yield of alpha-, beta-, and gamma- cyclodextrins was increased 1.4-fold by the addition of ethanol. In particular, the yield of beta-cyclodextrins in the presence of 10% (vol/vol) ethanol was 1.6-fold that without ethanol. The CGTase was stable and active in the presence of large amounts of various organic solvents. 相似文献
78.
Shimizu N Tarui H Mori N Nishida R Kuwahara Y 《Bioscience, biotechnology, and biochemistry》2003,67(2):308-313
The opisthonotal gland secretion of the acarid mite, Caloglyphus polyphyllae, contained two new monoterpenes, (E)-2-(2-hydroxyethylidene)-6-methyl-5-heptenal (1) and (E)-2-(2-hydroxyethyl)-6-methyl-2,5-heptadienal (2), to which we have given the trivial names alpha- and beta-acariolal in relation to alpha- and beta-acaridial (3 and 4), respectively. Elucidation of the structure of 1 was established mainly from 1H-NMR and GC/MS spectral data after partial purification, together with the fact that 1 was recovered in the more-polar fraction from a silica gel column than alpha- and beta-acaridial (3 and 4) present in the secretion. Compound 2 was obtained in the same fraction as a mixture with 1. Based on the facts that 2 had the same molecular weight by GC/MS and the same polarity as that of 1, compound 2 was assumed to be a structural analog of 1. The structures of compounds 1 and 2 were confirmed by their synthesis in nine and ten respective steps starting from alpha-bromo-gamma-butyrolactone. 相似文献
79.
Properties of rice cooked with commercial water-soluble soybean polysaccharides extracted under weakly acidic conditions from soybean cotyledons 总被引:4,自引:0,他引:4
Furuta H Nakamura A Ashida H Asano H Maeda H Mori T 《Bioscience, biotechnology, and biochemistry》2003,67(4):677-683
It has been found that commercial water-soluble soybean polysaccharides (SSPS) can make cooked rice and noodles non-sticky and prevent rice grains and noodles from adhering to each other. We studied in detail the phenomenon of rice cooked with SSPS. We assumed that the phenomenon resulted from the interaction between SSPS and starch during cooking, and studied the effects of SSPS on the gelatinizing behavior of rice starch by using a Rapid-Visco-Analyzer. The addition of SSPS reduced the viscosity of the gelatinized starch. This lower final viscosity of the rice starch was more distinct from than that of potato starch. These results imply that the properties of SSPS in forming a non-sticky condition might result from a decrease in the viscosity of the gelatinized starch. 相似文献
80.
Morphological and molecular variation in Mitchella undulata,with special reference to the systematic treatment of the dwarf form from Yakushima 总被引:1,自引:0,他引:1
Morphological and molecular variation in Mitchella undulata Siebold et Zucc. was examined to evaluate the genetic basis for recognizing the dwarf variety, M. undulata var. minor Masamune. Considerable variation in leaf size in M. undulata, but no obvious morphological discontinuities, were found between the normal and dwarf varieties. Instead, a weak cline running from the Pacific Ocean to the Sea of Japan was found. Anatomical observations of leaf blades revealed that the large variation in leaf size can be attributed to variation in the number of leaf cells and not to differences in cell size. A molecular analysis based on sequences of rDNA internal transcribed spacer regions indicated that there were two major genotypes in M. undulata with minor variation in haplotypes resulting from additional substitutions or putative recombination. The dwarf form from Yakushima was neither genetically uniform nor apparently differentiated from other populations. From these results, we conclude that the dwarf form of M. undulata should be treated at the rank of forma. 相似文献