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61.
Mi-Na Kim Seong-Mi Park Dong-Hyuk Cho Hack-Lyoung Kim Mi-Seung Shin Myung-A Kim Kyung-Soon Hong Wan-Joo Shim 《Biology of sex differences》2018,9(1):52
Background
Evidence suggests that epicardial adipose tissue (EAT) is closely related to coronary artery stenosis (CAS). However, sexual dimorphism may be present in adipose tissue, and its influence on CAS between men and women is controversial. We assessed the relationship between EAT and CAS by sex and menopausal status in patients with suspected angina.Methods
Six hundred twenty-eight consecutive patients (men/women n?=?257/371; mean age = 59.9?±?10.2?years) who had chest pain for angina and underwent coronary angiography were included. CAS was defined as >?50% luminal narrowing of at least one epicardial coronary artery. EAT thickness was measured by transthoracic echocardiography.Results
Of the 628 patients, 52.1% (n?=?134) of men and 35.3% (n?=?131) of women had CAS. The mean EAT thickness was not different between men and women and was larger in patients with CAS (8.04?±?2.39 vs 6.58?±?1.88?mm, P?<?0.001). EAT thickness was independently associated with CAS in both sexes (P?<?0.001). The odds ratio (OR) of EAT for the presence of CAS was higher in men (OR?=?1.43, 95% confidence interval [CI] 1.21–1.69) than in women (OR?=?1.24, 95% CI 1.10–1.40). EAT thickness was larger in postmenopausal women than in premenopausal women (7.59?±?2.25 vs 5.80?±?1.57?mm, P?<?0.001) and was independently related with CAS (OR?=?1.24, 95% CI 1.09–1.41). This was not the case in premenopausal women.Conclusion
In patients with suspected angina, an increase in EAT thickness was independently related to the presence of CAS in both men and women, with it being stronger in men. According to menopausal status in women, EAT thickness is significantly associated with CAS only in postmenopausal women.62.
63.
Phosphate esters exist ubiquitously in nature in the form of nucleoside phosphates (nucleotides) as components of RNA (or DNA), sugar nucleotides for glycosylation of oligosaccharides or proteins, activated form of proteins responding to extracellular signals, and chemical mediators playing central roles in intracellular signaling signals. Phosphorylation of anti-viral nucleoside analogues by intracellular kinases yields nucleoside phosphates (nucleotide) as biologically active forms as anti-viral agents. Development of artificial phosphate receptors would afford new methodologies for detection, separation, or transport of biologically important phosphates. Herein, a recent progress of artificial phosphate receptors is reviewed with special focus on macrocyclic polyamines and their metal complexes as a new prototype. In comparison to most of the previous artificial receptors (most of them are organic molecules), our system characteristically works in aqueous solution at neutral pH with extremely strong affinities with phosphate anions. Moreover, zinc(II)-macrocyclic tetraamine (cyclen) complexes were discovered to selectively bind thymine and uracil, so that nucleotides of these bases are specifically recognized by the bis(Zn2+-cyclen) complexes. 相似文献
64.
The amino‐terminal tail of Hxt11 confers membrane stability to the Hxt2 sugar transporter and improves xylose fermentation in the presence of acetic acid 下载免费PDF全文
Hyun Yong Shin Jeroen G. Nijland Paul P. de Waal Arnold J. M. Driessen 《Biotechnology and bioengineering》2017,114(9):1937-1945
Hxt2 is a glucose repressed, high affinity glucose transporter of the yeast Saccharomyces cerevisiae and is subjected to high glucose induced degradation. Hxt11 is a sugar transporter that is stably expressed at the membrane irrespective the sugar concentration. To transfer this property to Hxt2, the N‐terminal tail of Hxt2 was replaced by the corresponding region of Hxt11 yielding a chimeric Hxt11/2 transporter. This resulted in the stable expression of Hxt2 at the membrane and improved the growth on 8% d ‐glucose and 4% d ‐xylose. Mutation of N361 of Hxt11/2 into threonine reversed the specificity for d ‐xylose over d ‐glucose with high d ‐xylose transport rates. This mutant supported efficient sugar fermentation of both d ‐glucose and d ‐xylose at industrially relevant sugar concentrations even in the presence of the inhibitor acetic acid which is normally present in lignocellulosic hydrolysates. Biotechnol. Bioeng. 2017;114: 1937–1945. © 2017 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc. 相似文献
65.
66.
Screening of promoters from metagenomic DNA and their use for the construction of expression vectors
Han SS Lee JY Kim WH Shin HJ Kim GJ 《Journal of microbiology and biotechnology》2008,18(10):1634-1640
This study was focused on the screening of valuable genetic resources, such as promoters from metagenome, and describes a promoter trapping system with a bidirectional probe concept, which can select promoters or operons from various biological resources including metagenomic DNA. A pair of reporters, GFP and DsRed, facing the opposite direction without promoters, is an effective system that can function regardless of the direction of inserted promoters. The feasibility of this system was tested for the isolation of constitutively expressed promoters in E. coli from a soil metagenome, resulting in a potential pool of various promoters for practical application. The analyses of structural organization of the trapped genes demonstrated that constitutively expressible promoters in E. coli were broadly distributed within the metagenome, and suggested that some promoters were useful for the construction of expression vectors. Based on these observations, three constitutive promoters were employed in the expression vector system and their potentials for practical application were evaluated in terms of expression level, protein solubility, and effects on host growth. 相似文献
67.
Atsushi Kawakami Takashi Kitsukawa Shin Takagi Hajime Fujisawa 《Developmental neurobiology》1996,29(1):1-17
Neuropilin (previously A5) is a cell surface glycoprotein that was originally identified in Xenopus tadpole nervous tissues. In Xenopus, neuropilin is expressed on both the presynaptic and postsynaptic elements in the visual and general somatic sensory systems, suggesting a role in neuronal cell recognition. In this study, we identified a mouse homologue of neuropilin and examined its expression in developing mouse nervous tissues. cDNA cloning and sequencing revealed that the primary structure of the mouse neuropilin was highly similar to that of Xenopus and that the extracellular segment of the molecule possessed several motifs that were expected to be involved in cell-cell interaction. Immunohistochemistry and in situ hybridization analyses in mice indicated that the expression of neuropilin was restricted to particular neuron circuits. Neuropilin protein was localized on axons but not on the somata of neurons. The expression of neuropilin persisted through the time when axons were actively growing to form neuronal connections. These observations suggest that neuropilin is involved in growth, fasciculation, and targeting for a particular groups of axons. © 1996 John Wiley & Sons, Inc. 相似文献
68.
Sequential analysis of cell differentials and IFN-gamma production of splenocytes from mice infected with Toxoplasma gondii 总被引:3,自引:0,他引:3
To assess the relationship between the changes of cellular components and the production of Th1 cytokine in the immune tissue, inbred C57BL/6 mice were orally infected with 40 cysts of 76K strain of Toxoplasma gondii. The sequential change of cell differentials and IFN-gamma production of splenocytes were analyzed by Diff-Quik stain and RT-PCR. There were no significant proportional changes of cellular components of splenocytes until day 4 postinfection (PI) as compared to those of day 0, and the relative percentage of macrophages and neutrophils/eosinophils increased significantly (p < 0.01) thereafter. The expression of IFN-gamma mRNA of CD3- cells was observed from day 1 PI at a low level. However, IFN-gamma production of CD3+ cells increased significantly from day 4 PI (p < 0.01) which progressively increased thereafter. These findings provide the relative percentages of granulocytes and macrophages were increased in conjunction with increase of total number of splenocytes after oral infection with T. gondii in the susceptible murine hosts, and lymphocytes were the major cellular components and the important source of IFN-gamma. 相似文献
69.
We present a simple and rapid method to isolate extracellular vesicles (EVs) by using a polyethylene glycol/dextran aqueous two-phase system (ATPS). This system isolated more than ~75% of melanoma-derived EVs from a mixture of EVs and serum proteins. To increase the purity of EVs, a batch procedure was combined as additional steps to remove protein contaminants, and removed more than ~95% of the protein contaminants. We also performed RT-PCR and western blotting to verify the diagnostic applicability of the isolated EVs, and detected mRNA derived from melanoma cells and CD81 in isolated EVs. 相似文献
70.