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101.
Kang Yun Hee Ji Na Young Lee Chung Il Lee Hee Gu Kim Jae Wha Yeom Young IL Kim Dae Ghon Yoon Seung Kew Kim Jong Wan Park Pil Je Song Eun Young 《Amino acids》2011,40(3):1003-1013
Amino Acids - Endothelial cell-specific molecule-1 (ESM-1) is a secretory proteoglycan comprising a mature polypeptide of 165 amino acids and a single dermatan sulfate. The aim of this study was to... 相似文献
102.
Sib–sib or, more generally, family resemblance for dispersal seems a widespread characteristic of vertebrates, and the birthplace has the potential to shape the dynamics and features of animal populations. Dispersal studies have often stressed the fundamental link between the fate of dispersers and population dynamics, but few have focused on the dispersal directions of individuals, despite the profound implications that this may have on population distribution, structure, dynamics and viability. We investigated the directions followed by 72 radio‐tagged dispersers (43 males and 29 females from 14 nest sites) in an eagle owl Bubo bubo population, and assessed their a) inter‐individual distances during dispersal and b) age at dispersal departure. For siblings, as well as potential‐siblings (i.e. individuals born in the same nest in different years), the birthplace influenced inter‐individual distances and dispersal directions, i.e. dispersers from the same nest moved to similar locations during the study; moreover, in each year, individuals from the same birthplace moved across the same areas in a short time period. Finally, siblings and potential‐siblings born in the same nest in different years started dispersal at similar ages. Based on the movement patterns of dispersers we discuss: a) the potential implications of the birthplace‐dependent dispersal on the ideal free distribution theory, as well as in terms of kin competition, inbreeding avoidance and population dynamics; and, more generally, b) the effect of the temporal features of the natal dispersal on the concept of habitat suitability vs density of individuals developed by the ideal free distribution theory. 相似文献
103.
Escobar H Reyes-Vargas E Jensen PE Delgado JC Crockett DK 《Journal of proteome research》2011,10(5):2494-2507
Systematic investigation of cellular process by mass spectrometric detection of peptides obtained from proteins digestion or directly from immuno-purification can be a powerful tool when used appropriately. The true sequence of these peptides is defined by the interpretation of spectral data using a variety of available algorithms. However peptide match algorithm scoring is typically based on some, but not all, of the mechanisms of peptide fragmentation. Although algorithm rules for soft ionization techniques generally fit very well to tryptic peptides, manual validation of spectra is often required for endogenous peptides such as MHC class I molecules where traditional trypsin digest techniques are not used. This study summarizes data mining and manual validation of hundreds of peptide sequences from MHC class I molecules in publically available data files. We herein describe several important features to improve and quantify manual validation for these endogenous peptides--post automated algorithm searching. Important fragmentation patterns are discussed for the studied MHC Class I peptides. These findings lead to practical rules that are helpful when performing manual validation. Furthermore, these observations may be useful to improve current peptide search algorithms or development of novel software tools. 相似文献
104.
Fisher M Downie H Welten MC Delgado I Bain A Planzer T Sherman A Sang H Tickle C 《PloS one》2011,6(4):e18661
Hoxd13, Tbx2, Tbx3, Sall1 and Sall3 genes are candidates for encoding antero-posterior positional values in the developing chick wing and specifying digit identity. In order to build up a detailed profile of gene expression patterns in cell lineages that give rise to each of the digits over time, we compared 3 dimensional (3D) expression patterns of these genes during wing development and related them to digit fate maps. 3D gene expression data at stages 21, 24 and 27 spanning early bud to digital plate formation, captured from in situ hybridisation whole mounts using Optical Projection Tomography (OPT) were mapped to reference wing bud models. Grafts of wing bud tissue from GFP chicken embryos were used to fate map regions of the wing bud giving rise to each digit; 3D images of the grafts were captured using OPT and mapped on to the same models. Computational analysis of the combined computerised data revealed that Tbx2 and Tbx3 are expressed in digit 3 and 4 progenitors at all stages, consistent with encoding stable antero-posterior positional values established in the early bud; Hoxd13 and Sall1 expression is more dynamic, being associated with posterior digit 3 and 4 progenitors in the early bud but later becoming associated with anterior digit 2 progenitors in the digital plate. Sox9 expression in digit condensations lies within domains of digit progenitors defined by fate mapping; digit 3 condensations express Hoxd13 and Sall1, digit 4 condensations Hoxd13, Tbx3 and to a lesser extent Tbx2. Sall3 is only transiently expressed in digit 3 progenitors at stage 24 together with Sall1 and Hoxd13; then becomes excluded from the digital plate. These dynamic patterns of expression suggest that these genes may play different roles in digit identity either together or in combination at different stages including the digit condensation stage. 相似文献
105.
Delgado S Castillo Neyra R Quispe Machaca VR Ancca Juárez J Chou Chu L Verastegui MR Moscoso Apaza GM Bocángel CD Tustin AW Sterling CR Comrie AC Náquira C Cornejo del Carpio JG Gilman RH Bern C Levy MZ 《PLoS neglected tropical diseases》2011,5(2):e970
Background
The history of Chagas disease control in Peru and many other nations is marked by scattered and poorly documented vector control campaigns. The complexities of human migration and sporadic control campaigns complicate evaluation of the burden of Chagas disease and dynamics of Trypanosoma cruzi transmission.Methodology/Principal Findings
We conducted a cross-sectional serological and entomological study to evaluate temporal and spatial patterns of T. cruzi transmission in a peri-rural region of La Joya, Peru. We use a multivariate catalytic model and Bayesian methods to estimate incidence of infection over time and thereby elucidate the complex history of transmission in the area. Of 1,333 study participants, 101 (7.6%; 95% CI: 6.2–9.0%) were confirmed T. cruzi seropositive. Spatial clustering of parasitic infection was found in vector insects, but not in human cases. Expanded catalytic models suggest that transmission was interrupted in the study area in 1996 (95% credible interval: 1991–2000), with a resultant decline in the average annual incidence of infection from 0.9% (95% credible interval: 0.6–1.3%) to 0.1% (95% credible interval: 0.005–0.3%). Through a search of archival newspaper reports, we uncovered documentation of a 1995 vector control campaign, and thereby independently validated the model estimates.Conclusions/Significance
High levels of T. cruzi transmission had been ongoing in peri-rural La Joya prior to interruption of parasite transmission through a little-documented vector control campaign in 1995. Despite the efficacy of the 1995 control campaign, T. cruzi was rapidly reemerging in vector populations in La Joya, emphasizing the need for continuing surveillance and control at the rural-urban interface. 相似文献106.
A new chromene, cumanensic acid (1), together with eight known compounds have been isolated from the aerial part of Piper cf. cumanense Kunth (Piperaceae). Chromene structure was identified on the basis of spectroscopic analysis and comparison with literature data. The compound showed antifungal activity against Fusarium oxysporum f. sp. dianthi and Botrytis cinerea. 相似文献
107.
Delgado O Kaisani AA Spinola M Xie XJ Batten KG Minna JD Wright WE Shay JW 《PloS one》2011,6(7):e22023
While the adult murine lung utilizes multiple compartmentally restricted progenitor cells during homeostasis and repair, much less is known about the progenitor cells from the human lung. Translating the murine stem cell model to humans is hindered by anatomical differences between species. Here we show that human bronchial epithelial cells (HBECs) display characteristics of multipotent stem cells of the lung. These HBECs express markers indicative of several epithelial types of the adult lung when experimentally tested in cell culture. When cultured in three different three-dimensional (3D) systems, subtle changes in the microenvironment result in unique responses including the ability of HBECs to differentiate into multiple central and peripheral lung cell types. These new findings indicate that the adult human lung contains a multipotent progenitor cell whose differentiation potential is primarily dictated by the microenvironment. The HBEC system is not only important in understanding mechanisms for specific cell lineage differentiation, but also for examining changes that correlate with human lung diseases including lung cancer. 相似文献
108.
Gold mining in the Peruvian Amazon: global prices, deforestation, and mercury imports 总被引:4,自引:0,他引:4
Many factors such as poverty, ineffective institutions and environmental regulations may prevent developing countries from managing how natural resources are extracted to meet a strong market demand. Extraction for some resources has reached such proportions that evidence is measurable from space. We present recent evidence of the global demand for a single commodity and the ecosystem destruction resulting from commodity extraction, recorded by satellites for one of the most biodiverse areas of the world. We find that since 2003, recent mining deforestation in Madre de Dios, Peru is increasing nonlinearly alongside a constant annual rate of increase in international gold price (∼18%/yr). We detect that the new pattern of mining deforestation (1915 ha/year, 2006–2009) is outpacing that of nearby settlement deforestation. We show that gold price is linked with exponential increases in Peruvian national mercury imports over time (R2 = 0.93, p = 0.04, 2003–2009). Given the past rates of increase we predict that mercury imports may more than double for 2011 (∼500 t/year). Virtually all of Peru''s mercury imports are used in artisanal gold mining. Much of the mining increase is unregulated/artisanal in nature, lacking environmental impact analysis or miner education. As a result, large quantities of mercury are being released into the atmosphere, sediments and waterways. Other developing countries endowed with gold deposits are likely experiencing similar environmental destruction in response to recent record high gold prices. The increasing availability of satellite imagery ought to evoke further studies linking economic variables with land use and cover changes on the ground. 相似文献
109.
110.
The isolation of a new diterpene lactone and two known diterpenoid acids from the aerial parts of Viguiera maculata is reported. 相似文献