553 research outputs found
Solubilization of Proteins in 2DE: An Outline
Protein solubilization for two-dimensional electrophoresis (2DE) has to break
molecular interactions to separate the biological contents of the material of
interest into isolated and intact polypeptides. This must be carried out in
conditions compatible with the first dimension of 2DE, namely isoelectric
focusing. In addition, the extraction process must enable easy removal of any
nonprotein component interfering with the isoelectric focusing. The constraints
brought in this process by the peculiar features of isoelectric focusing are
discussed, as well as their consequences in terms of possible solutions and
limits for the solubilization process
Genomic Exploration of Distinct Molecular Phenotypes Steering Temozolomide Resistance Development in Patient-Derived Glioblastoma Cells
Chemotherapy using temozolomide is the standard treatment for patients with glioblastoma. Despite treatment, prognosis is still poor largely due to the emergence of temozolomide resistance. This resistance is closely linked to the widely recognized inter- and intra-tumoral heterogeneity in glioblastoma, although the underlying mechanisms are not yet fully understood. To induce temozolomide resistance, we subjected 21 patient-derived glioblastoma cell cultures to Temozolomide treatment for a period of up to 90 days. Prior to treatment, the cellsâ molecular characteristics were analyzed using bulk RNA sequencing. Additionally, we performed single-cell RNA sequencing on four of the cell cultures to track the evolution of temozolomide resistance. The induced temozolomide resistance was associated with two distinct phenotypic behaviors, classified as âadaptiveâ (ADA) or ânon-adaptiveâ (N-ADA) to temozolomide. The ADA phenotype displayed neurodevelopmental and metabolic gene signatures, whereas the N-ADA phenotype expressed genes related to cell cycle regulation, DNA repair, and protein synthesis. Single-cell RNA sequencing revealed that in ADA cell cultures, one or more subpopulations emerged as dominant in the resistant samples, whereas N-ADA cell cultures remained relatively stable. The adaptability and heterogeneity of glioblastoma cells play pivotal roles in temozolomide treatment and contribute to the tumorâs ability to survive. Depending on the tumorâs adaptability potential, subpopulations with acquired resistance mechanisms may arise.</p
Water Ice in Lunar Simulants: NIRVSS Drilling Observations
No abstract availabl
Medically Biodegradable Hydrogenated Amorphous Silicon Microspheres
[EN] Hydrogenated amorphous silicon colloids of low surface area (<5 m(2)/g) are shown to exhibit complete in-vitro biodegradation into orthosilicic acid within 10-15 days at 37 degrees C. When converted into polycrystalline silicon colloids, by high temperature annealing in an inert atmosphere, microparticle solubility is dramatically reduced. The data suggests that amorphous silicon does not require nanoscale porosification for full in-vivo biodegradability. This has significant implications for using a-Si:H coatings for medical implants in general, and orthopedic implants in particular. The high sphericity and biodegradability of submicron particles may also confer advantages with regards to contrast agents for medical imaging.This work has been partially supported by the Spanish CICyT projects, FIS2009-07812, Consolider CSD2007-046, MAT2009-010350 and PROMETEO/2010/043.Shabir, Q.; Pokale, A.; Loni, A.; Johnson, DR.; Canham, L.; Fenollosa Esteve, R.; Tymczenko, MK.... (2011). Medically Biodegradable Hydrogenated Amorphous Silicon Microspheres. Silicon. 3(4):173-176. https://doi.org/10.1007/s12633-011-9097-4S17317634Salonen J, Kaukonen AM, Hirvonen J, Lehto VP (2008) J Pharmaceutics 97:632â53Anglin EJ, Cheng L, Freeman WR, Sailor MJ (2008) Adv Drug Deliv Rev 60:1266â77OâFarrell N, Houlton A, Horrocks BR (2006) Int J Nanomedicine 1:451â72Canham LT (1995) Adv Mater 7:1037, PCT patent WO 97/06101,1999Park JH, Gui L, Malzahn G, Ruoslahti E, Bhatia SN, Sailor MJ (2009) Nature Mater 8:331â6Cullis AG, Canham LT, Calcott PDJ (1997) J Appl Phys 82:909â66Canham LT, Reeves CR (1996) Mat Res Soc Symp 414:189â90Edell DJ, Toi VV, McNeil VM, Clark LD (1992) IEEE Trans Biomed Eng 39:635â43Fenollosa R, Meseguer F, Tymczenko M (2008) Adv Mater 20:95Fenollosa R, Meseguer F, Tymczenko M, Spanish Patent P200701681, 2007Pell LE, Schricker AD, Mikulec FV, Korgel BA (2004) Langmuir 20:6546XifrĂ©-Perez E, Fenollosa R, Meseguer F (2011) Opt Express 19:3455â63Fenollosa R, Ramiro-Manzano F, Tymczenko M, Meseguer F (2010) J Mater Chem 20:5210XifrĂ©-PĂ©rez E, Domenech JD, Fenollosa R, Muñoz P, Capmany J, Meseguer F (2011) Opt Express 19â4:3185â92Rodriguez I, Fenollosa R, Meseguer F, Cosmetics & Toiletries 2010;42â49Ramiro-Manzano F, Fenollosa R, XifrĂ©-PĂ©rez E, GarĂn M, Meseguer F (2011) Adv Mater 23:3022â3025. doi: 10.1002/adma.201100986Iler RK (1979) Chemistry of silica: solubility, polymerization, colloid & surface properties & biochemistry. Wiley, New YorkTanaka K, Maruyama E, Shimado T, Okamoto H (1999) Amorphous silicon. Wiley, New York, NYPatterson AL (1939) Phys Rev 56:978â82Canham LT, Reeves CL, King DO, Branfield PJ, Gabb JG, Ward MC (1996) Adv Mater 8:850â2Iler RK In: Chemistry of silica: solubility, polymerization, colloid & surface properties &Biochemistry. Wiley, New York, NYFinnie KS, Waller DJ, Perret FL, Krause-Heuer AM, Lin HQ, Hanna JV, Barbe CJ (2009) J Sol-Gel Technol 49:12â8Zhao D, Huo Q, Feng J, Chmelka BF, Stucky GD (1998) J Am Chem Soc 120:6024â36Fan D, Akkaraju GR, Couch EF, Canham LT, Coffer JL (2010) Nanoscale 1:354â61Tasciotti E, Godin B, Martinez JO, Chiappini C, Bhavane R, Liu X, Ferrari M (2011) Mol Imaging 10:56â
The state of the art in the analysis of two-dimensional gel electrophoresis images
Software-based image analysis is a crucial step in the biological interpretation of two-dimensional gel electrophoresis experiments. Recent significant advances in image processing methods combined with powerful computing hardware have enabled the routine analysis of large experiments. We cover the process starting with the imaging of 2-D gels, quantitation of spots, creation of expression profiles to statistical expression analysis followed by the presentation of results. Challenges for analysis software as well as good practices are highlighted. We emphasize image warping and related methods that are able to overcome the difficulties that are due to varying migration positions of spots between gels. Spot detection, quantitation, normalization, and the creation of expression profiles are described in detail. The recent development of consensus spot patterns and complete expression profiles enables one to take full advantage of statistical methods for expression analysis that are well established for the analysis of DNA microarray experiments. We close with an overview of visualization and presentation methods (proteome maps) and current challenges in the field
Alcohol consumption and sport: a cross-sectional study of alcohol management practices associated with at-risk alcohol consumption at community football clubs
BackgroundExcessive alcohol consumption is responsible for considerable harm from chronic disease and injury. Within most developed countries, members of sporting clubs participate in at-risk alcohol consumption at levels above that of communities generally. There has been limited research investigating the predictors of at-risk alcohol consumption in sporting settings, particularly at the non-elite level. The purpose of this study was to examine the association between the alcohol management practices and characteristics of community football clubs and at-risk alcohol consumption by club members.MethodsA cross sectional survey of community football club management representatives and members was conducted. Logistic regression analysis (adjusting for clustering by club) was used to determine the association between the alcohol management practices (including alcohol management policy, alcohol-related sponsorship, availability of low- and non-alcoholic drinks, and alcohol-related promotions, awards and prizes) and characteristics (football code, size and location) of sporting clubs and at-risk alcohol consumption by club members.ResultsMembers of clubs that served alcohol to intoxicated people [OR: 2.23 (95% CI: 1.26-3.93)], conducted ‘happy hour’ promotions [OR: 2.84 (95% CI: 1.84-4.38)] or provided alcohol-only awards and prizes [OR: 1.80 (95% CI: 1.16-2.80)] were at significantly greater odds of consuming alcohol at risky levels than members of clubs that did not have such alcohol management practices. At-risk alcohol consumption was also more likely among members of clubs with less than 150 players compared with larger clubs [OR:1.45 (95% CI: 1.02-2.05)] and amongst members of particular football codes.ConclusionsThe findings of this study suggest a need and opportunity for the implementation of alcohol harm reduction strategies targeting specific alcohol management practices at community football clubs.<br /
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