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951.
Role of the cellular prion protein in oligodendrocyte precursor cell proliferation and differentiation in the developing and adult mouse CNS 总被引:1,自引:0,他引:1
Bribián A Fontana X Llorens F Gavín R Reina M García-Verdugo JM Torres JM de Castro F del Río JA 《PloS one》2012,7(4):e33872
There are numerous studies describing the signaling mechanisms that mediate oligodendrocyte precursor cell (OPC) proliferation and differentiation, although the contribution of the cellular prion protein (PrP(c)) to this process remains unclear. PrP(c) is a glycosyl-phosphatidylinositol (GPI)-anchored glycoprotein involved in diverse cellular processes during the development and maturation of the mammalian central nervous system (CNS). Here we describe how PrP(c) influences oligodendrocyte proliferation in the developing and adult CNS. OPCs that lack PrP(c) proliferate more vigorously at the expense of a delay in differentiation, which correlates with changes in the expression of oligodendrocyte lineage markers. In addition, numerous NG2-positive cells were observed in cortical regions of adult PrP(c) knockout mice, although no significant changes in myelination can be seen, probably due to the death of surplus cells. 相似文献
952.
Matt Maughan Germán Bollero D. K. Lee Robert Darmody Stacy Bonos Laura Cortese James Murphy Roch Gaussoin Matthew Sousek David Williams Linda Williams Fernando Miguez Thomas Voigt 《Global Change Biology Bioenergy》2012,4(3):253-265
Miscanthus × giganteus is a C4 perennial grass that shows great potential as a high‐yielding biomass crop. Scant research has been published that reports M. × giganteus growth and biomass yields in different environments in the United States. This study investigated the establishment success, plant growth, and dry biomass yield of M. × giganteus during its first three seasons at four locations (Urbana, IL; Lexington, KY; Mead, NE; Adelphia, NJ) in the United States. Three nitrogen rates (0, 60, and 120 kg ha?1) were applied at each location each year. Good survival of M. × giganteus during its first winter was observed at KY, NE, and NJ (79–100%), and poor survival at IL (25%), due to late planting and cold winter temperatures. Site soil conditions, and growing‐season precipitation and temperature had the greatest impact on dry biomass yield between season 2 (2009) and season 3 (2010). Ideal 2010 weather conditions at NE resulted in significant yield increases (P < 0.0001) of 15.6–27.4 Mg ha?1 from 2009 to 2010. Small yield increases in KY of 17.1 Mg ha?1 in 2009 to 19.0 Mg ha?1 in 2010 could be attributed to excessive spring rain and hot dry conditions late in the growing season. Average M. ×giganteus biomass yields in NJ decreased from 16.9 to 9.7 Mg ha?1 between 2009 and 2010 and were related to hot dry weather, and poor soil conditions. Season 3 yields were positively correlated with end‐of‐season plant height () and tiller density (). Nitrogen fertilization had no significant effect on plant height, tiller density, or dry biomass yield at any of the sites during 2009 or 2010. 相似文献
953.
Silke R. Kirchner Alexander Ohlinger Tom Pfeiffer Alexander S. Urban Fernando D. Stefani Andras Deak Andrey A. Lutich Jochen Feldmann 《Journal of biophotonics》2012,5(1):40-46
Microfluidic jetting is a promising method to produce giant unilamellar phospholipid vesicles for mimicking living cells in biomedical studies. We have investigated the chemical composition of membranes of vesicles prepared using this approach by means of Raman scattering spectroscopy. The membranes of all jetted vesicles are found to contain residuals of the organic solvent decane used in the preparation of the initial planar membrane. The decane inclusions are randomly distributed over the vesicle surface area and vary in thickness from a few to several tens of nanometers. Our findings point out that the membrane properties of jetted vesicles may differ considerably from those of vesicles prepared by other methods and from those of living cells. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
954.
Schröder PC Fernández-Irigoyen J Bigaud E Serna A Renández-Alcoceba R Lu SC Mato JM Prieto J Corrales FJ 《Journal of Proteomics》2012,75(10):2855-2868
955.
de la Cuesta F Barderas MG Calvo E Zubiri I Maroto AS Darde VM Martin-Rojas T Gil-Dones F Posada-Ayala M Tejerina T Lopez JA Vivanco F Alvarez-Llamas G 《Journal of Proteomics》2012,75(10):2960-2971
Aims
Early detection of cardiovascular diseases and knowledge of underlying mechanisms is essential. Tissue secretome studies resemble more closely to the in vivo situation, showing a much narrower protein concentrations dynamic range than plasma. This study was aimed to the analysis of human arterial tissue secretome and to the quantitative comparison of healthy and atherosclerotic secretome to discover proteins with key roles in atherosclerosis development.Methods and results
Secretomes from three biological replicates of human atherosclerotic coronary arteries (APC), preatherosclerotic coronaries (PC) and mammaries (M) were analyzed by LC-MS/MS. The identified proteins were submitted to Ingenuity Pathway Analysis (IPA) tool. Label-free MS/MS based quantification was performed and validated by immunohistochemistry. 64 proteins were identified in the 3 replicates of at least one of the 3 groups and 15 secreted proteins have not been previously reported in plasma. Four proteins were significantly released in higher amounts by mammary tissue: gelsolin, vinculin, lamin A/C and phosphoglucomutase 5.Conclusion
The study of tissue secretome reveals key proteins involved in atherosclerosis which have not been previously reported in plasma. Novel proteins are here highlighted which could be potential therapeutic targets in clinical practice. This article is part of a Special Issue entitled: Proteomics: The clinical link. 相似文献956.
Purpose: This study examines the association between marriage and colorectal endoscopy exam, and whether this association varies by gender and financial benefits of marriage including improved access to health insurance and pooled family income. Methods: Representative survey data of the non-institutionalized United States population were used from the 2000, 2005, and 2008 National Health Interview Survey. Analyses targeted persons 50-85 years of age without a personal history of cancer and with complete information on all study variables (n=21,760). Multivariate logistic regression was used to model marital status differences in the probability of undergoing a colorectal endoscopy exam with interaction effects used to model variation over time by gender, health insurance, and poverty level. Results: Married persons were more likely than unmarried persons to report ever having undergone a colorectal endoscopy exam (odds ratio [OR], 1.21; 95% confidence interval [CI], 1.12-1.29), and the difference between married and unmarried persons in the probability of undergoing a colorectal endoscopy exam remained stable over time. Married persons were more likely than unmarried persons to report having undergone a colorectal endoscopy exam within the past 10 years (OR, 1.49; 95% CI, 1.15-1.95). For each survey year, married men were significantly more likely than women and unmarried men to report having undergone a colorectal endoscopy exam. For example, in 2008, 56% of married men reported having undergone a colorectal endoscopy exam, compared to 49% of unmarried men, 52% of married women, and 50% of unmarried women. Among persons with health insurance, married persons were significantly more likely than unmarried persons to have undergone a colorectal endoscopy exam. Among persons who were poor, there was no difference by marital status in the likelihood of having undergone a colorectal endoscopy exam. However, among persons who were not poor, married persons were more likely than unmarried persons to have undergone a colorectal endoscopy exam. Conclusion: Given that colorectal endoscopy exams are a potentially life-saving procedure, persistently higher uptake of colorectal endoscopy for married persons over time may be an important health promoting benefit of marriage. Therefore, clinicians and policy makers should focus on improving the use of cancer prevention services among unmarried persons. 相似文献
957.
Although some studies have shown diversity in HIV integrase (IN) genes, none has focused particularly on the gene evolving in epidemics in the context of recombination. The IN gene in 157 HIV-1 integrase inhibitor-na?ve patients from the S?o Paulo State, Brazil, were sequenced tallying 128 of subtype B (23 of which were found in non-B genomes), 17 of subtype F (8 of which were found in recombinant genomes), 11 integrases were BF recombinants, and 1 from subtype C. Crucially, we found that 4 BF recombinant viruses shared a recurrent recombination breakpoint region between positions 4900 and 4924 (relative to the HXB2) that includes 2 gRNA loops, where the RT may stutter. Since these recombinants had independent phylogenetic origin, we argue that these results suggest a possible recombination hotspot not observed so far in BF CRF in particular, or in any other HIV-1 CRF in general. Additionally, 40% of the drug-na?ve and 45% of the drug-treated patients had at least 1 raltegravir (RAL) or elvitegravir (EVG) resistance-associated amino acid change, but no major resistance mutations were found, in line with other studies. Importantly, V151I was the most common minor resistance mutation among B, F, and BF IN genes. Most codon sites of the IN genes had higher rates of synonymous substitutions (dS) indicative of a strong negative selection. Nevertheless, several codon sites mainly in the subtype B were found under positive selection. Consequently, we observed a higher genetic diversity in the B portions of the mosaics, possibly due to the more recent introduction of subtype F on top of an ongoing subtype B epidemics and a fast spread of subtype F alleles among the B population. 相似文献
958.
Fabrizi F Mincione F Somma T Scozzafava G Galassi F Masini E Impagnatiello F Supuran CT 《Journal of enzyme inhibition and medicinal chemistry》2012,27(1):138-147
The clinically used sulfonamide carbonic anhydrase (CA, EC 4.2.1.1) inhibitor dorzolamide (DRZ), a new sulfonamide CA inhibitor also incorporating NO-donating moieties, NCX250, and isosorbide mononitrate (ISMN) (an NO-donating compound with no CA inhibitory properties) were investigated for their intraocular pressure (IOP) lowering effects in rabbits with carbomer-induced glaucoma. NCX250 was more effective than DRZ or ISMN on lowering IOP, increasing ocular hemodynamics, decreasing the inflammatory processes and ocular apoptosis in this animal model of glaucoma. NO participate to the regulation of IOP in glaucoma, having also antiapoptotic and anti-inflammatory effects. The ophthalmic artery, both systolic and diastolic velocities, were significantly reduced in NCX250-treated eyes in comparison to DRZ treated ones, suggesting thus a beneficial effect of NCX250 on the blood supply to the optic nerve. Combining CA inhibition with NO-donating moieties in the same compound offers an excellent approach for the management of glaucoma. 相似文献
959.
ABSTRACT: Centrally necrotizing carcinoma is a rare subtype of breast carcinoma, which is characterized by an extensive central necrotic zone accounting for at least 70% of the cross-sectional area of the neoplasm. This central necrotic zone, in turn, is surrounded by a narrow rim of proliferative viable tumor cells. We report an unusual clinical situation in which a patient whose evident breast mass suggested an ipsilateral local recurrence and for which numerous attempts to confirm the histological diagnosis had failed. The patient was treated with a radical mastectomy based on clinical suspicion of breast cancer recurrence after an undesirable delay. In this case, the narrow rim of viable malignant tissue had a thickness of 0.5 to 8 mm, and the centrally necrotizing carcinoma had a central zone with a predominance of fibrosis. The special features of this case led to a misdiagnosis and to an evident clinical local recurrence. 相似文献
960.
Alain Ghysen Christine Dambly‐Chaudière Denis Coves Fernando de la Gandara Aurelio Ortega 《Evolution & development》2012,14(2):204-211
The posterior lateral line system (PLL) of teleost fish comprises a number of mechanosensory organs arranged in defined patterns on the body surface. Embryonic patterns are largely conserved among teleosts, yet adult patterns are highly diverse. Although changes in pattern modify the perceptual abilities of the system, their developmental origin remains unknown. Here we compare the processes that underlie the formation of the juvenile PLL pattern in Thunnus thynnus, the bluefin tuna, to the processes that were elucidated in Danio rerio, the zebrafish. In both cases, the embryonic PLL comprises five neuromasts regularly spaced along the horizontal myoseptum, but the juvenile PLL comprises four roughly parallel anteroposterior lines in zebrafish, whereas it is a simple dorsally arched line in tuna fish. We examined whether this difference involves evolutionary novelties, and show that the same mechanisms mediate the transition from embryonic to juvenile patterns in both species. We conclude that the marked difference in juveniles depends on a single change (dorsal vs. ventral migration of neuromasts) in the first days of larval life. 相似文献