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991.
为了建立一个高效的高产油微藻诱变育种流程,微藻中油脂含量快速和准确的测定在其中具有重要作用。在本研究中,首先利用低场核磁共振技术,建立了直接检测干藻粉和培养液中小球藻油脂含量的方法,其信号强度与细胞中油脂含量存在特异的线性关系,干藻粉和藻液中油脂含量与信号值拟合的R2均高于0.99,说明该方法用于小球藻油脂含量的检测是准确和可行的。同时该方法与传统油脂测量方法相比,具有快速、简便和准确等优点。但其通量不及尼罗红染色法,因此,我们开发了将尼罗红染色法用于初筛,低场核磁共振技术用于复筛的新型高通量藻种复合筛选方法,并将此筛选方法应用于一种异养高产油原壳小球藻的诱变育种过程中。首先从3 098株诱变藻种中初筛得到108株具有较高油脂含量的藻株,然后利用低场核磁共振技术复筛得到9株高产油性能的藻株,其中一株甘油三酯含量超过20%,比原始藻株提高1倍,培养168 h后培养液油脂浓度达到5 g/L,证明此诱变育种流程不仅提高了筛选的效率还可靠且可行。 相似文献
992.
Solar Cells: Heterojunction‐Depleted Lead‐Free Perovskite Solar Cells with Coarse‐Grained B‐γ‐CsSnI3 Thin Films (Adv. Energy Mater. 24/2016) 下载免费PDF全文
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994.
Objective
To analyze plasma myostatin levels and investigate their relationship with right ventricular (RV) function in patients with cor pulmonale secondary to chronic obstructive pulmonary disease (COPD).Methods
The study recruited 81 patients with advanced COPD and 40 age-matched controls. The patients were divided into two groups: those with cor pulmonale and those without. Echocardiography was used to evaluate RV function and morphology, and the value of tricuspid annular plane systolic excursion (TAPSE) less than 16 mm was considered RV dysfunction. Plasma myostatin levels were analyzed by enzyme-linked immunosorbent assay, and B-type natriuretic peptide (BNP) levels were analyzed as a comparison of myostatin.Results
The data detected cor pulmonale in 39/81 patients, with the mean value of TAPSE of 14.3 mm. Plasma myostatin levels (ng/mL) were significantly higher in patients with cor pulmonale (16.68 ± 2.95) than in those without (13.56 ± 3.09), and much higher than in controls (8.79±2.79), with each p<0.01. Significant differences were also found in plasma BNP levels among the three groups (p<0.05). Multivariate regression analysis suggested that myostatin levels were significantly correlated with the values of TAPSE and RV myocardium performance index among the COPD patients, and that BNP levels were significantly correlated only with systolic pulmonary arterial pressure, with each p<0.05.Conclusions
Plasma myostatin levels are increased in COPD patients who have cor pulmonale. Stronger correlations of plasma myostatin levels with echocardiographic indexes of the right heart suggest that myostatin might be superior to BNP in the early diagnosis of cor pulmonale in COPD. 相似文献995.
Yea Eun Kang Ji Min Kim Kyong Hye Joung Ju Hee Lee Bo Ram You Min Jeong Choi Min Jeong Ryu Young Bok Ko Min A. Lee Junguee Lee Bon Jeong Ku Minho Shong Ki Hwan Lee Hyun Jin Kim 《PloS one》2016,11(4)
The roles of adipokines, proinflammatory cytokines, and adipose tissue macrophages in obesity-associated insulin resistance have been explored in both animal and human studies. However, our current understanding of obesity-associated insulin resistance relies on studies of artificial metabolic extremes. The purpose of this study was to explore the roles of adipokines, proinflammatory cytokines, and adipose tissue macrophages in human patients with modest obesity and early metabolic dysfunction. We obtained omental adipose tissue and fasting blood samples from 51 females undergoing gynecologic surgery. We investigated serum concentrations of proinflammatory cytokines and adipokines as well as the mRNA expression of proinflammatory and macrophage phenotype markers in visceral adipose tissue using ELISA and quantitative RT-PCR. We measured adipose tissue inflammation and macrophage infiltration using immunohistochemical analysis. Serum levels of adiponectin and leptin were significantly correlated with HOMA-IR and body mass index. The levels of expression of MCP-1 and TNF-α in visceral adipose tissue were also higher in the obese group (body mass index ≥ 25). The expression of mRNA MCP-1 in visceral adipose tissue was positively correlated with body mass index (r = 0.428, p = 0.037) but not with HOMA-IR, whereas TNF-α in visceral adipose tissue was correlated with HOMA-IR (r = 0.462, p = 0.035) but not with body mass index. There was no obvious change in macrophage phenotype or macrophage infiltration in patients with modest obesity or early metabolic dysfunction. Expression of mRNA CD163/CD68 was significantly related to mitochondrial-associated genes and serum inflammatory cytokine levels of resistin and leptin. These results suggest that changes in the production of inflammatory biomolecules precede increased immune cell infiltration and induction of a macrophage phenotype switch in visceral adipose tissue. Furthermore, serum resistin and leptin have specific roles in the regulation of adipose tissue macrophages in patients with modest obesity or early metabolic dysfunction. 相似文献
996.
Damao Wang Eun Ju Yun Sooah Kim Do Hyoung Kim Nari Seo Hyun Joo An Jae-Han Kim Nam Yong Cheong Kyoung Heon Kim 《Bioprocess and biosystems engineering》2016,39(6):959-966
This study was performed to evaluate the effectiveness of acidic pretreatment in increasing the enzymatic digestibility of alginate from brown macroalgae. Pretreatment with 1 % (w/v) sulfuric acid at 120 °C for 30 min produced oligosaccharides, mannuronic acid, and guluronic acid. Enzymatic saccharification of pretreated alginate by alginate lyases produced 52.2 % of the theoretical maximal sugar yield, which was only 7.5 % higher than the sugar yield obtained with unpretreated alginate. Mass spectrometric analyses of products of the two reactions revealed that acidic pretreatment and enzymatic saccharification produced saturated monomers (i.e., mannuronic and guluronic acid) with saturated oligosaccharides and unsaturated monomers (i.e., 4-deoxy-l-erythro-5-hexoseulose uronic acid; DEH), respectively. While DEH is further metabolized by microorganisms, mannuronic acid and guluronic acid are not metabolizable. Because of the poor efficacy in increasing enzymatic digestibility and owing to the formation of non-fermentable saturated monomers, acidic pretreatment cannot be recommended for enzymatic saccharification and fermentation of alginate. 相似文献
997.
Abdullah Al Loman S. M. Mahfuzul Islam Qian Li Lu-Kwang Ju 《Bioprocess and biosystems engineering》2016,39(10):1501-1514
Soybean carbohydrate is often found to limit the use of protein in soy flour as food and animal feed due to its indigestibility to monogastric animal. In the current study, an enzymatic process was developed to produce not only soy protein concentrate and soy protein isolate without indigestible carbohydrate but also soluble reducing sugar as potential fermentation feedstock. For increasing protein content in the product and maximizing protein recovery, the process was optimized to include the following steps: hydrolysis of soy flour using an Aspergillus niger enzyme system; separation of the solid and liquid by centrifugation (10 min at 7500×g); an optional step of washing to remove entrapped hydrolysate from the protein-rich wet solid stream by ethanol (at an ethanol-to-wet-solid ratio (v/w) of 10, resulting in a liquid phase of approximately 60 % ethanol); and a final precipitation of residual protein from the sugar-rich liquid stream by heat treatment (30 min at 95 °C). Starting from 100 g soy flour, this process would produce approximately 54 g soy protein concentrate with 70 % protein (or, including the optional solid wash, 43 g with 80 % protein), 9 g soy protein isolate with 89 % protein, and 280 ml syrup of 60 g/l reducing sugar. The amino acid composition of the soy protein concentrate produced was comparable to that of the starting soy flour. Enzymes produced by three fungal species, A. niger, Trichoderma reesei, and Aspergillus aculeatus, were also evaluated for effectiveness to use in this process. 相似文献
998.
Global analysis of phosphoproteome dynamics in embryonic development of zebrafish (Danio rerio) 总被引:1,自引:0,他引:1 下载免费PDF全文
Oh Kwang Kwon Sun Ju Kim You‐Mie Lee Young‐Hoon Lee Young‐Seuk Bae Jin Young Kim Xiaojun Peng Zhongyi Cheng Yingming Zhao Sangkyu Lee 《Proteomics》2016,16(1):136-149
The zebrafish (Danio rerio) is a popular animal model used for studies on vertebrate development and organogenesis. Recent research has shown a similarity of approximately 70% between the human and zebrafish genomes and about 84% of human disease‐causing genes have common ancestry with that of the zebrafish genes. Zebrafish embryos have a number of desirable features, including transparency, a large size, and rapid embryogenesis. Protein phosphorylation is a well‐known PTM, which can carry out various biological functions. Recent MS developments have enabled the study of global phosphorylation patterns by using MS‐based proteomics coupled with titanium dioxide phosphopeptide enrichment. In the present study, we identified 3500 nonredundant phosphorylation sites on 2166 phosphoproteins and quantified 1564 phosphoproteins in developing embryos of zebrafish. The distribution of Ser/Thr/Tyr phosphorylation sites in zebrafish embryos was found to be 88.9, 10.2, and 0.9%, respectively. A potential kinase motif was predicted using Motif‐X analysis, for 80% of the identified phosphorylation sites, with the proline‐directed motif appearing most frequently, and 35 phosphorylation sites having the pSF motif. In addition, we created six phosphoprotein clusters based on their dynamic pattern during the development of zebrafish embryos. Here, we report the largest dataset of phosphoproteins in zebrafish embryos and our results can be used for further studies on phosphorylation sites or phosphoprotein dynamics in zebrafish embryos. 相似文献
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1000.