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991.
992.
Katsutoshi Ando Yoshinori Okada Miki Akiba Takashi Kondo Tomohiro Kawamura Meinoshin Okumura Fengshi Chen Hiroshi Date Takeshi Shiraishi Akinori Iwasaki Naoya Yamasaki Takeshi Nagayasu Masayuki Chida Yoshikazu Inoue Toyohiro Hirai Kuniaki Seyama Michiaki Mishima Respiratory Failure Research Group of the Japanese Ministry of Health Labour Welfare 《PloS one》2016,11(1)
Background
Lung transplantation has been established as the definitive treatment option for patients with advanced lymphangioleiomyomatosis (LAM). However, the prognosis after registration and the circumstances of lung transplantation with sirolimus therapy have never been reported.Methods
In this national survey, we analyzed data from 98 LAM patients registered for lung transplantation in the Japan Organ Transplantation Network.Results
Transplantation was performed in 57 patients as of March 2014. Survival rate was 86.7% at 1 year, 82.5% at 3 years, 73.7% at 5 years, and 73.7% at 10 years. Of the 98 patients, 21 had an inactive status and received sirolimus more frequently than those with an active history (67% vs. 5%, p<0.001). Nine of twelve patients who remained inactive as of March 2014 initiated sirolimus before or while on a waiting list, and remained on sirolimus thereafter. Although the statistical analysis showed no statistically significant difference, the survival rate after registration tended to be better for lung transplant recipients than for those who awaited transplantation (p = 0.053).Conclusions
Lung transplantation is a satisfactory therapeutic option for advanced LAM, but the circumstances for pre-transplantation LAM patients are likely to alter with the use of sirolimus. 相似文献993.
994.
The following 1-substituted derivatives of 5-methylphenazine and 5-ethylphenazine were synthesized: 1-(3-carboxypropyloxy)-5-methylphenazine (1B), 1-(3-carboxypropyloxy)-5-ethylphenazine (2B), 1-(3-ethoxycarbonylpropyloxy)-5-ethylphenazine (2C) and 1-[N-(2-aminoethyl)carbamoylpropyloxy]-5-ethylphenazine (2D); their spectra, stability and reactivity as electron mediators were investigated, together with those of 5-methylphenazine (1A) and 5-ethylphenazine (2A). The 1-substituted derivatives are all insensitive to light and the derivatives of 5-ethylphenazine are more stable than those of 5-methylphenazine under neutral and alkaline conditions; 2B is the most stable of all the derivatives. The spectral properties of the decomposed compounds showed that photodecomposition of 1A and 2A is associated with hydroxylation at position 1, alkali decomposition of 1A and 1B with elimination of the 5-methyl group and alkali decomposition of 2A, 2B, and 2D with a ring-opening reaction. The second-order rate constant k1 for the reaction of the phenazine derivatives with NADH was measured under steady-state conditions. The k1 values vary depending on the substituents at positions 1 and 5: the values for 1A, 1B, 2A, 2B, 2C and 2D are 1.83 mM-1 s-1, 3.33 mM-1 s-1, 0.75 mM-1 s-1, 1.42 mM-1 s-1, 1.68 mM-1 s-1 and 2.03 mM-1 s-1, respectively. The rate constants, k2 and k3, for the reactions of the reduced form of 2B with oxygen and with 3-(4',5'-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium ion, respectively, were k2 = 1.21 mM-1 s-1 and k3 = 91 mM-1 s-1. These phenazine derivatives have potential applications in the biochemical field. 相似文献
995.
Age-associated changes in DNA structure and mRNA level were studied for the c-myc gene in spleen and liver of mice at 2, 14 and 26 months of age. Neither amplification nor rearrangement of the gene was detected in either tissue at any age. However, a significant alteration was observed in the methylation profile. The profile of the gene and its vicinity was determined using various methylation-sensitive restriction enzymes. In both tissues, the gene had an unmethylated domain ranging from -2 kb upstream of the 5' end of the first exon to the 3' end of the first intron. It was flanked by partially methylated regions, where age-dependent changes as well as tissue specificity were observed. In the spleen, age-related hypomethylation was observed at both the 3' and 5' sides of the domain. In contrast, hypermethylation was found in the liver only at the 3' side. The steady-state level of c-myc mRNA showed a drastic decrease in liver from youth to middle age, while splenic mRNA changed little. The correlation between the changes of mRNA and DNA methylation is discussed. 相似文献
996.
Structures of the asparagine-linked oligosaccharides of guinea-pig factor B of the alternative complement pathway.
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This paper describes the structures of the asparagine-linked oligosaccharides of two forms of guinea-pig Factor B of the alternative complement pathway with different Mr values. Oligosaccharides were quantitatively liberated from both glycoproteins by hydrazinolysis, fractionated by paper electrophoresis and Bio-Gel P-4 column chromatography, and their structures determined by sequential exoglycosidase digestions in conjunction with methylation analysis. Both glycoproteins were shown to have the same biantennary complex-type oligosaccharides but it is suggested that they contain different numbers of oligosaccharide chains. 相似文献
997.
Asymmetric distribution and temperature-dependent clustering of filipin-sterol complexes in the nuclear membrane of Ehrlich ascites tumor cells 总被引:1,自引:0,他引:1
When Ehrlich ascites tumor (EAT) cells were fixed at 4 degrees C and freeze-fractured, patchy areas having no intramembrane particles were visible in the nuclear envelope. The particle free areas (PFAs) were not seen on fixation at 28 degrees C, indicating that appearance of PFAs was caused by a kind of thermotropic phase separation. The PFAs were detected only in the nuclear membrane, and not in the plasma membrane. Most of them were present in the outer membrane of the nuclear envelope. In cells fixed at 4 degrees C, and treated with filipin all the filipin-sterol complexes appeared in clusters located in the PFAs. In contrast, the filipin-sterol complexes were evenly distributed in cells fixed at 28 degrees C. This suggests that at low temperature, molecules of cholesterol gather in the PFAs. Temperature-dependent cluster formation was seen only in the complexes of the nuclear membrane, suggesting that the cholesterol in the nuclear membrane is more mobile than that in the plasma membrane. In addition, the distribution of filipin-sterol complexes in the nuclear envelope was asymmetric. The complexes were seen only in the outer (cytoplasmic), but not in the inner (nucleoplasmic) membrane of the nuclear envelope, reflecting differences in the structural, and presumably functional, characteristics of the outer and inner nuclear membranes. 相似文献
998.
K Oki S Nakama A Asano Y Okada 《Biochemical and biophysical research communications》1975,67(1):331-337
HVJ(Sendai virus)-induced fusion of Ehrlich ascites tumor cells was found to be stimulated by treatments which increase the intracellular level of cyclic AMP. This stimulation was optimal at an external concentration of Ca++ of about 0.5 mM. During the process of cell fusion, the intracellular concentration of cyclic AMP was increased with a maximum at 2 min after the initiation of the fusion reaction.Evidence is also presented which suggests that the increase of the cyclic nucleotide is a part of control mechanism of HVJ-induced fusion of eukariotic cells. Thus, this cyclic AMP-stimulated process could be one of the step(s) requiring ATP and Ca++, both of which are necessary for the overall fusion process of the tumor cells. 相似文献
999.
The growth of a stalked bacterium, Caulobacter crescentus, has been synchronized easily and reproducibly by a new method. When this bacterium is grown to a late log phase in nutrient broth at 30 C with aeration, swarmer cells are accumulated in the culture to 80% of the whole cell population. When this culture is inoculated into fresh pre-warmed broth at twentyfold dilution, it immediately initiates synchronous cell growth. Simultaneously, synchronous cell differentiation is monitored by the susceptibility of the cells to RNA phage infection. The swarmer cells accumulated in the late log phase of growth possess nearly the same susceptibility to RNA phage infection as those in the early log phase of growth while RNA phage-adsorbing capacity is lower in such swarmer cells. It is suggested that the swarmer cells accumulated in the late log phase of growth have lost some pili. 相似文献
1000.
A new light-induced absorbance change having a maximum at 561nm was discovered in the thalli, as well as in isolated chloroplastsof a green alga, Bryopsis maxima Okamura. Another simultaneous change also occurred at 515 nm. The magnitudeof the 561 nm change was several-fold larger than that at 515nm and much larger than could be explained by an oxidation-reductionchange in cytochromes contained in chloroplasts. There was noabsorbance change in the Soret region that may be correlatedto the 561 nm change. Both 561 and 515 nm changes showed a spike-liketime course pattern, both having a half-rise time of about 20msec. Effects of inhibitors and uncouplers such as DCMU, Cl-CCPand gramicidin J on the absorbance change were also similarat 561 and at 515 nm. We inferred that the 561 nm change is related to photophosphorylationand possibly to the membrane potential in a way similar to the515 nm change. (Received March 27, 1974; ) 相似文献