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61.
Cost‐effective and rapid lysis of Saccharomyces cerevisiae cells for quantitative western blot analysis of proteins,including phosphorylated eIF2α 下载免费PDF全文
Valerie de Boor Jan M. Gebler Richard C. Silva Evelyn Sattlegger 《Yeast (Chichester, England)》2017,34(9):371-382
The common method for liberating proteins from Saccharomyces cerevisiae cells involves mechanical cell disruption using glass beads and buffer containing inhibitors (protease, phosphatase and/or kinase inhibitors), followed by centrifugation to remove cell debris. This procedure requires the use of costly inhibitors and is laborious, in particular when many samples need to be processed. Also, enzymatic reactions can still occur during harvesting and cell breakage. As a result low‐abundance and labile proteins may be degraded, and enzymes such as kinases and phosphatases may still modify proteins during and after cell lysis. We believe that our rapid sample preparation method helps overcome the above issues and offers the following advantages: (a) it is cost‐effective, as no inhibitors and breaking buffer are needed; (b) cell breakage is fast (about 15 min) since it only involves a few steps; (c) the use of formaldehyde inactivates endogenous proteases prior to cell lysis, dramatically reducing the risk of protein degradation; (d) centrifugation steps only occur prior to cell lysis, circumventing the problem of losing protein complexes, in particular if cells were treated with formaldehyde intended to stabilize and capture large protein complexes; and (e) since formaldehyde has the potential to instantly terminate protein activity, this method also allows the study of enzymes in live cells, i.e. in their true physiological environment, such as the short‐term effect of a drug on enzyme activity. Taken together, the rapid sample preparation procedure provides a more accurate snapshot of the cell's protein content at the time of harvesting. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
62.
Marilsa S. S. Santini Evelyn C. Koga Davi C. Aragon Elsa H. W. Santana Marcela R. Costa Giselle N. Costa Lina C. Aragon‐Alegro 《Journal of food science》2012,77(11):M604-M608
Abstract: A dried tomato‐flavored probiotic cream cheese (P) containing Lactobacillus paracasei Lpc‐37 was developed for the purpose of this study. The same product, but without probiotic addition (C) was used as control. Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris were used as lactic starter cultures. Chemical composition analyses and sensory tests were performed on days 1 and 7, respectively. Titratable acidity, pH value and L. paracasei population were determined every 7 d during the refrigerated storage (21 d) of the cream cheeses. The experiment and analyses were performed in triplicate, using standard methods. Probiotic population remained greater than 107 CFU/g throughout the storage period, thereby characterizing the product as potentially probiotic. Cream cheeses C and P did not differ on the sensory tests, both obtaining good overall acceptance by the consumers, of which 82.6% stated that they certainly or probably would buy the product. Practical Application: Lactobacillus paracasei Lpc‐37 is a probiotic bacterium and clinical studies have shown that this microorganism beneficially affects its host. In general, dried tomato‐flavored products and cream cheese are products with good acceptance by the consumers. Thus, regular consumption of the probiotic cream cheese developed in this study may have positive effects on health and well being of people if incorporated into their diet. 相似文献
63.
Narek Gharibyan Ashlee Dailey Derek R. McLain Evelyn M. Bond Walter A. Moody Steffen Happel 《溶剂提取与离子交换》2013,31(4):391-407
Due to the similar chemical properties between the neighboring trivalent actinide elements americium and curium, their extraction behavior is often perceived as indistinguishable. In this work, the characterization of seven extraction chromatography resins (TEVA, TRU, DGA(N), Actinide, Ln, Ln2, and Ln3) for these trivalent actinides from acidic matrices (HNO3, HCl, and HBr) has provided some evidence to the contrary. In most cases, Am(III) and Cm(III) exhibit identical extraction properties. However, separation is possible with TRU and DGA(N) resins as demonstrated in this study. The extraction shows a strong dependency on the specific anion in solution that follows the order NO3?>Br?>Cl?. 相似文献
64.
65.
Cottonseed flavonoids as lipid antioxidants 总被引:3,自引:0,他引:3
Carleen Cairns Whittern Evelyn E. Miller Dan E. Pratt 《Journal of the American Oil Chemists' Society》1984,61(6):1075-1078
Methanolic extracts of cottonseeds were found to possess antioxidant activity. Separation of antioxidant components was achieved
by paper, thin layer (TLC) and gas liquid chromatography (GLC) and spectral analysis. Chromatographic technique indicated
that the flavonoids quercetin and rutin were the major flavonoids present. GLC analysis of the cottonseed extract eluted from
TLC plates, developed in n-butanol/acetic acid/water (4:1:5, v/v/v) and ethyl acetate/methyl ethyl ketone/formic acid/water
(5:3:1:1, v/v/v) solvents, corresponded in retention times to the rutin standard (10−4 M). TMS derivatives of the aglycone fraction, prepared by acid hydrolysis, correlated to the retention time of quercetin.
Spectral analysis of the aglycone fraction also indicated quercetin derivatives to be present in cottonseed. The glycosyl
substitution of the flavonoids were identified by the 3 chromatographic procedures to be glucose and rhamnose. Chromogenic
spray reagents were used to further characterize the cottonseed flavonoids and flavonoid components on TLC and paper chromatography.
The investigation, therefore, demonstrated that quercetin derivatives appear to be the main flavonoid species in cottonseed.
Rutin was found to be one of the major quercetin glycosides. Quercetin and rutin are shown to possess potent antioxidant activity. 相似文献
66.
Traditionally, electric utilities have forecast the demand for their product and planned a supply system to satisfy the market. Rather than treating the forecast demand as a given, Florida Power & Light Company (FPL), has established a marketing planning function to alter future demand through direct involvement in the marketplace. The crucial element in management's evaluation of opportunities to build, maintain, shift, or reduce customer load is a better understanding of our customers, including their preferences and behavior in purchasing energy. A market analysis utilizing a comprehensive marketing planning model, the Load Management Strategy Testing Model (LMSTM), indicates that the commercial sector, in general, and customer thermal energy storage, in particular, is a demand-side option the Company will actively promote. That identification is made by a detailed market feasibility study FPL is currently managing. 相似文献
67.
In this article we describe a clinical proficiency review required of 3rd-year graduate students, and we present data from a study of its psychometric properties and utility. Students' oral and written case presentations were evaluated on seven dimensions by a six-member panel composed of faculty and students. Moderately high interjudge reliabilities were achieved, although the level of agreement between rater pairs was related to the level of similarity of their theoretical orientation. Significant correlations were obtained between panel ratings and those of current field placement supervisors, but not with supervisor's ratings from prior or subsequent placements. Performance on the clinical proficiency review was relatively independent of academic performance measures such as course grades and scores on a six-part comprehensive examination. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
Levine Fredric M.; Sandeen Evelyn; Murphy Christopher M. 《Canadian Metallurgical Quarterly》1992,29(3):410
The therapist is faced with the dilemma of conducting therapy at an idiographic level while psychology research is conducted and organized at a nomothetic level. Increasingly, psychiatric diagnosis serves as the conceptual bridge from the science of psychology to its clinical applications. Yet diagnosis has a number of well-known limitations for determining treatment. An alternative conceptual bridge from nomothetic science to clinical applications draws from 3 overlapping categories: (1) general causal principles derived from all areas of scientific psychology; (2) probabilities and base rate data associated with the covariation of psychological problems; and (3) clinical outcome research. Suggestions as to how therapists can use these nomothetic categories to form treatment strategies are given. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Contreras Josefina M.; López Irene R.; Rivera-Mosquera Evelyn T.; Raymond-Smith Laura; Rothstein Karen 《Canadian Metallurgical Quarterly》1999,13(2):228
Associations between grandmother and partner involvement and adjustment were examined among 61 Puerto Rican adolescent mothers. Results indicated that associations between grandmother involvement and adjustment were moderated by the adolescents' level of acculturation. Greater support was related to less symptomatology and parenting stress when acculturation scores were low but to more symptomatology and parenting stress when acculturation scores were high. Social support from partners was related to less symptomatology (but not parenting stress). Although coresidence with a partner was related to greater symptomatology, a significant interaction effect revealed that coresidence was associated with greater symptomatology mainly when mothers perceived their partners as providing low levels of support. Results are discussed in light of Latino cultural values and normative developmental issues. Implications for intervention strategies are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Saroj Rajthala Anjie Min Himalaya Parajuli Kala Chand Debnath Borghild Ljkjel Kristin Marie Hoven Arild Kvalheim Stein Lybak Evelyn Neppelberg Olav Karsten Vintermyr Anne Christine Johannessen Dipak Sapkota Daniela Elena Costea 《International journal of molecular sciences》2021,22(21)
Background: Knowledge on the role of miR changes in tumor stroma for cancer progression is limited. This study aimed to investigate the role of miR dysregulation in cancer-associated fibroblasts (CAFs) in oral squamous cell carcinoma (OSCC). Methodology: CAF and normal oral fibroblasts (NOFs) were isolated from biopsies of OSCC patients and healthy individuals after informed consent and grown in 3D collagen gels. Total RNA was extracted. Global miR expression was profiled using Illumina version 2 panels. The functional impact of altered miR-204 expression in fibroblasts on their phenotype and molecular profile was investigated using mimics and inhibitors of miR-204. Further, the impact of miR-204 expression in fibroblasts on invasion of adjacent OSCC cells was assessed in 3D-organotypic co-cultures. Results: Unsupervised hierarchical clustering for global miR expression resulted in separate clusters for CAF and NOF. SAM analysis identified differential expression of twelve miRs between CAF and NOF. Modulation of miR-204 expression did not affect fibroblast cell proliferation, but resulted in changes in the motility phenotype, expression of various motility-related molecules, and invasion of the adjacent OSCC cells. 3′ UTR miR target reporter assay showed ITGA11 to be a direct target of miR-204. Conclusions: This study identifies differentially expressed miRs in stromal fibroblasts of OSCC lesions compared with normal oral mucosa and it reveals that one of the significantly downregulated miRs in CAF, miR-204, has a tumor-suppressive function through inhibition of fibroblast migration by modulating the expression of several different molecules in addition to directly targeting ITGA11. 相似文献