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11.
The use of biological means for ground improvement have become popular, which generally works through the process called microbially-induced calcium carbonate precipitation (MICP). Many studies indicate successful application of MICP based improvement with multiple bacteria and on several soils. Given the proven performance of MICP, this study aims to examine the MICP process by comparing the calcium carbonate precipitation ability of widely studied bacteria, i.e., Sporosarcina pasteurii and relatively under-recognized bacteria, i.e., Bacillus licheniformis to outline the formation success. For this purpose, two different sands were tested for observing precipitation behavior using a series of syringe tests. Furthermore, the effect of concentration and inclusion of calcium chloride for nutrition of bacteria, saturation with water, and hybrid use of two bacteria were investigated in some tests for diversification. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray spectroscopy (EDS) were used for the interpretation of results. Results indicated that Sporosarcina pasteurii had performed superior over Bacillus licheniformis when achieving calcium carbonate precipitation in tests for both sands. In addition, many intriguing SEM images contributed to the literature of MICP monitoring, highlighting the effects of the variables investigated. 相似文献
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Sheiner PA Florman SS Emre S Fishbein T Schwartz ME Miller CM Boros P 《Mediators of inflammation》2001,10(1):37-41
BACKGROUND: Recurrence of hepatitis C after liver transplantation is an almost universal occurrence. T-cell derived cytokines have an important role in the development of liver damage associated with chronic hepatitis C, their post-transplant levels, however, have not been correlated with histologic recurrence of the disease. AIMS: We sought to analyze levels of TNF-alpha, soluble IL-2 receptor, IL-4 and IL-10 at 1 month, 6 months and 1 year after transplantation in 27 patients undergoing transplantation for hepatitis C related end-stage liver disease. METHODS: HCV RNA levels were monitored by a branched-chain DNA signal amplification assay. Diagnosis of recurrent hepatitis was based on 1-year protocol biopsies and on biopsies performed for liver enzyme elevations. RESULTS: Recurrent hepatitis C was detected in 52% (n=14) of the 27 patients. HCV RNA levels rose over time in all patients regardless of histologic recurrence. TNF-alpha, and IL-4 levels, although elevated, did not show specific patterns over time or in correlation with recurrence. Similarly, the early elevation followed by a gradual decrease over the first year in the amount of soluble IL-2 receptor was not related to histologic recurrence. We observed a significant increase in circulating IL-10 levels over the first year in patients with biopsy-proven recurrence, while patients with no signs of histologic recurrence displayed increased, but steady levels. CONCLUSIONS: These results suggest that while these cytokines are associated with post-transplant recurrence of hepatitis C, their production may be altered by additional factors. 相似文献
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Kevin Nelson Christopher Bobba Emre Eren Tyler Spata Malak Tadres Don Hayes Jr. Sylvester M. Black Samir Ghadiali Bryan A. Whitson 《Journal of visualized experiments : JoVE》2015,(96)
The number of acceptable donor lungs available for lung transplantation is severely limited due to poor quality. Ex-Vivo Lung Perfusion (EVLP) has allowed lung transplantation in humans to become more readily available by enabling the ability to assess organs and expand the donor pool. As this technology expands and improves, the ability to potentially evaluate and improve the quality of substandard lungs prior to transplant is a critical need. In order to more rigorously evaluate these approaches, a reproducible animal model needs to be established that would allow for testing of improved techniques and management of the donated lungs as well as to the lung-transplant recipient. In addition, an EVLP animal model of associated pathologies, e.g., ventilation induced lung injury (VILI), would provide a novel method to evaluate treatments for these pathologies. Here, we describe the development of a rat EVLP lung program and refinements to this method that allow for a reproducible model for future expansion. We also describe the application of this EVLP system to model VILI in rat lungs. The goal is to provide the research community with key information and “pearls of wisdom”/techniques that arose from trial and error and are critical to establishing an EVLP system that is robust and reproducible. 相似文献
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Serhat Büyükleblebici Pürhan Barbaros Tuncer Mustafa N. Bucak Umut Taşdemir Ayşe Eken Olga Büyükleblebici Emre Durmaz Serpil Sarıözkan Burcu Ü. Endirlik 《Cryobiology》2014
There are few studies performed for investigating the roles of different ratio and cryoprotectants with dithiothreitol or sucrose on sperm motility characteristics and antioxidant capacities of post-thawed bull spermatozoa. The objectives of this study were to compare glycerol (G) and ethylene glycol (EG) at different concentrations as cryoprotectants and dithiothreitol (D) or sucrose (S) (with/without) as antioxidants in Tris extender for cryopreservation of bull semen. Twenty-four ejaculates obtained from three bulls were included in the study. Each ejaculate was split into four equal aliquots and diluted using both of the Tris extenders with glycerol (5% or 7%) or ethylene glycol (3% or 5%). After that, each extenders were split into three equal aliquots and diluted using both of the dithiothreitol 5 mM or sucrose 25 mM, and control (without additives) was cooled to 4 °C and frozen in 0.25-ml French straws. when compared to control, different doses cryoprotectants and antioxidants addition no significantly increased the percentages of post-thaw sperm progressive and motitilities, acrosome abnormality and plasma membrane integrity (P > 0.05). However, EG3 + S yielded the greatest percentages of the total abnormality (P < 0.05). As regard to antioxidant activities G7 and EG5 led to lowest MDA activity with or without D or S but, these results were not supported to the GPx activity (P < 0.01). The sperm motion characteristics such as VAP, VCL, ALH and BCF gave significantly different results (P < 0.05). When compared the DNA integrity, different doses cryoprotectants without antioxidants addition significantly increased the percentages of the tail intensity and tail moment (P < 0.05). There were no significant differences observed in non-return rates among all treatment groups (P > 0.05). 相似文献
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Helmut Cölfen Thomas M. Laue Wendel Wohlleben Kristian Schilling Engin Karabudak Bradley W. Langhorst Emre Brookes Bruce Dubbs Dan Zollars Mattia Rocco Borries Demeler 《European biophysics journal : EBJ》2010,39(3):347-359
Progress in analytical ultracentrifugation (AUC) has been hindered by obstructions to hardware innovation and by software incompatibility. In this paper, we announce and outline the Open AUC Project. The goals of the Open AUC Project are to stimulate AUC innovation by improving instrumentation, detectors, acquisition and analysis software, and collaborative tools. These improvements are needed for the next generation of AUC-based research. The Open AUC Project combines on-going work from several different groups. A new base instrument is described, one that is designed from the ground up to be an analytical ultracentrifuge. This machine offers an open architecture, hardware standards, and application programming interfaces for detector developers. All software will use the GNU Public License to assure that intellectual property is available in open source format. The Open AUC strategy facilitates collaborations, encourages sharing, and eliminates the chronic impediments that have plagued AUC innovation for the last 20 years. This ultracentrifuge will be equipped with multiple and interchangeable optical tracks so that state-of-the-art electronics and improved detectors will be available for a variety of optical systems. The instrument will be complemented by a new rotor, enhanced data acquisition and analysis software, as well as collaboration software. Described here are the instrument, the modular software components, and a standardized database that will encourage and ease integration of data analysis and interpretation software. 相似文献
18.
Canan Ersoy Ganime Sadikoglu Hasan Orhan Metin Guclu Emre Sarandol Meral Demirci Akgun Alis Ozcakir Sazi Imamoglu 《Cytokine》2010,49(3):275-278
Obesity is the presence of either abnormal absolute amount or relative proportion of body fat. Contrary to gluteal obesity, visceral obesity is associated with different metabolic alterations including insulin resistance (IR). A relatively new adipocytokine visfatin is shown to be expressed predominantly in visceral fat and exhibit insulin-mimicking effects in rodents. It is still unclear whether serum visfatin levels are associated with increased total or visceral fat mass in humans. The aim of our study was to investigate the relation between visfatin and obesity parameters namely body mass index (BMI) and waist circumference (WaC) and IR in healthy female subjects. Eighty one female subjects ?20 years of age, having no diagnosis of glucose intolerance or diabetes, hypertension and dyslipidemia were chosen. The patients were divided into four groups according to their BMI and WaC values. Serum visfatin and HOMA-IR levels did not differ among groups. No correlation was detected between serum visfatin levels and obesity and metabolic parameters. In conclusion, we demonstrated that body fat distribution did not affect serum visfatin levels in healthy female subjects. Further studies are needed to clarify the exact factors influencing and determining serum visfatin levels and its clinical reflections. 相似文献
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Notman R Oren EE Tamerler C Sarikaya M Samudrala R Walsh TR 《Biomacromolecules》2010,11(12):3266-3274
We use replica-exchange molecular dynamics (REMD) to interrogate molecular structures and properties of four engineered dodecapeptides (in solution, in the absence of a surface) that have been shown to bind to quartz with different propensities. We find that all of the strong-binding peptides feature some polyproline type II secondary structure, have less conformational freedom, and feature fewer intrapeptide hydrogen bonds compared with the weak binder. The regions of contiguous proline content in a given sequence appear to play a role in fostering some of these properties of the strong binders. For preliminary insights into quartz binding, we perform lattice-matching studies between a grid corresponding with the quartz (100) surface and the strong-binding peptide REMD structures. Our findings indicate a commonality among the putative contact residues, even for peptide structures with very different backbone conformations. Furthermore, interpeptide interactions in solution are studied. Our preliminary findings indicate that the strong-binder interpeptide contacts are dominated by weak, nonspecific hydrophobic interactions, while the weak-binding peptide shows more variable behavior due to the distribution of charged residues. In summary, the solution structures of peptides appear to be significant. We propose that these differences in their intra- and interpeptide interactions can influence their propensity to bind onto a solid substrate. 相似文献