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41.
Halomonas variabilis and phylogenetically related organisms were isolated from various habitats such as Antarctic terrain and saline ponds, deep-sea sediment, deep-sea waters affected by hydrothermal plumes, and hydrothermal vent fluids. Ten strains were selected for physiological and phylogenetic characterization in detail. All of those strains were found to be piezotolerant and psychrotolerant, as well as euryhaline halophilic or halotolerant. Their stress tolerance may facilitate their wide occurrence, even in so-called extreme environments. The 16S rDNA-based phylogenetic relationship was complemented by analyses of the DNA gyrase subunit B gene (gyrB) and genes involved in the synthesis of the major compatible solute, ectoine: diaminobutyric acid aminotransferase gene (ectB) and ectoine synthase gene (ectC). The phylogenetic relationships of H. variabilis and related organisms were very similar in terms of 16S rDNA, gyrB, and ectB. The ectC-based tree was inconsistent with the other phylogenetic trees. For that reason, ectC was inferred to derive from horizontal transfer.  相似文献   
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The lactogenic hormone prolactin (PRL) regulates milk protein gene expression in mammary glands. To maintain homeostatic balance in the body, milk fat globule epidermal growth factor 8 (MFG-E8) is vital for phagocytic clearance of apoptotic cells. We investigated the effects of PRL on MFG-E8 expression in macrophages by evaluating its promoter function. Macrophages were stimulated with PRL, and the expression of MFG-E8 was determined using real-time PCR and Western blotting. The role of MFG-E8 on phagocytosis of apoptotic cells in PRL-treated macrophages was assessed using microscopy, while the response of PRL to MFG-E8 expression was evaluated using luciferase assay. Following treatment with PRL, significant up-regulations of the PRL receptor and MFG-E8 were observed in macrophages, though PRL-treated macrophages more efficiently engulfed apoptotic cells. The results of MFG-E8 promoter analysis showed considerable up-regulation of promoter activity in macrophages following PRL treatment and results from mutation analysis of the MFG-E8 promoter suggested that the C/EBPβ binding site was responsible for PRL-induced activation of the MFG-E8 promoter. C/EBPβ activity was found to be up-regulated in PRL-treated cells as revealed by an electrophoretic mobility shift assay (EMSA). In conclusion, PRL is a potent inducer of MFG-E8 expression in macrophages, while its effect is mediated by the presence of a responsive element in the MFG-E8 promoter.  相似文献   
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Background

No drugs have been approved for the treatment of patients with pulmonary hypertension (PH) secondary to idiopathic pulmonary fibrosis (IPF), particularly those with idiopathic honeycomb lung. This study was conducted to investigate the long-term efficacy and safety of bosentan for PH based on changes in prognosis and respiratory failure.

Methods

IPF patients with borderline or less severe PH and completely organized honeycomb lung were randomized (1:1) to bosentan or no treatment for PH for 2 years and assessed at baseline and every 6 months for respiratory failure, activities of daily living (ADL), lung and heart functions by right cardiac catheterization, and other parameters. An interim analysis was performed, however, following detection of a significant survival benefit favoring bosentan therapy.

Results

Significant differences were noted for the bosentan-treated (n?=?12) vs. untreated (n?=?12) groups in hospital-free survival (603.44?±?50.074 days vs. 358.87?±?68.65 days; hazard ratio [HR], 0.19; P?=?0.017) and overall survival (671 days vs. 433.78?±?66.98 days; HR, 0.10; P?=?0.0082). Again, significant improvements were noted for the bosentan-treated group from baseline to month 6 or 12 in several indices in ADL, pulmonary circulation, and %DLCO. Without requiring O2 inhalation, bosentan was associated with no increase but a trend toward a decrease in adverse events and an improvement in respiratory status.

Conclusions

Bosentan tended to improve prognosis and ADL without worsening respiratory failure in IPF patients with borderline or less severe PH and completely organized honeycomb lung alone.

Trial registration

This study was registered on December 18, 2010 with UMIN-CTR Clinical Trial as UMIN000004749 to investigate the long-term influence of bosentan on cardiac function, as well as its cardioprotective efficacy and safety, in patients with pulmonary hypertension secondary to concurrent COPD and IPF, respectively.
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The changes in the energy substrate utilized by the remnant liver were studied in relation to the changes in the cellular energy status of 25 and 70% hepatectomized rabbits. In 25% hepatectomized rabbits, the energy charge ((ATP+0.5ADP)(ATP+ADP+AMP)) level of the remnant liver remained unchanged, the energy substrate of which was predominantly glucose, rather than fatty acid. In contrast, in 70% hepatectomized rabbits, the energy production by the mitochondria was mainly dependent upon fatty acid oxidation at the early period after hepatectomy when the energy charge level decreased remarkably, and then upon glucose oxidation, concomitant with the restoration of the energy charge. It is suggested that the changes in the energy substrate utilized are closely related to those in the energy charge level and the mitochondrial phosphorylative activity of the remnant liver following hepatectomy.  相似文献   
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Thirty eight new compounds with juvenile hormone (JH) activity were synthesized and evaluated biologically on Bombyx mori L. Among them, the activities of 7,8-epoxy-4,8-dimethyl-1 -(p-ethylphenoxy)-3-undecene and 7,8-epoxy-4,8-dimethyl-l-(p-methylphenoxy)-3-undencene were proved to be more than two thousand times as high as that of the C18-Cecropia JH (mixed isomers). Structure-activity relationship of these compounds was discussed.  相似文献   
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This review is focusing on an industrially important enzyme, phospholipase D (PLD), exhibiting both transphosphatidylation and hydrolytic activities for various phospholipids. The transphosphatidylation activity of PLD is particularly useful for converting phosphatidylcholine (PC) into other phospholipids. During the last decade, the genes coding for PLD have been identified from various species including mammals, plants, yeast, and bacteria. However, detailed basic and applied enzymological studies on PLD have been hampered by the low productivity in these organisms. Efficient production of a recombinant PLD has also been unsuccessful so far. We recently isolated and characterized the PLD gene from Streptoverticillium cinnamoneum, producing a secretory PLD. Furthermore, we constructed an overexpression system for the secretory enzyme in an active and soluble form using Streptomyces lividans as a host for transformation of the PLD gene. The Stv. cinnamoneum PLD was proven to be useful for the continuous and efficient production of phosphatidylethanolamine (PE) from phosphatidylcholine. Thus, the secretory PLD is a promising catalyst for synthesizing new phospholipids possessing various polar head groups that show versatile physiological functions and may be utilized in food and pharmaceutical industries.  相似文献   
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