bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metformin restores endothelial function in aorta of diabetic rats
Authors: Sena Cristina M , Matafome Paulo , Louro Teresa , Nunes Elsa , Fernandes Rosa , Seiça Raquel M 
Published: January 2011

BACKGROUND AND PURPOSEThe effects of metformin, an antidiabetic agent that improves insulin sensitivity, on endothelial function have not been fully elucidated. This study was designed to assess the effect of metformin on impaired endothelial function, oxidative stress, inflammation and advanced glycation end products formation in type 2 diabetes mellitus.EXPERIMENTAL APPROACHGoto‐Kakizaki (GK) rats, an animal model of nonobese type 2 diabetes, fed with normal and high‐fat diet during 4 months were treated with metformin for 4 weeks before evaluation. Systemic oxidative stress, endothelial function, insulin resistance, nitric oxide (NO) bioavailability, glycation and vascular oxidative stress were determined in the aortic rings of the different groups. A pro‐inflammatory biomarker the chemokine CCL2 (monocyte chemoattractant protein‐1) was also evaluated.KEY RESULTSHigh‐fat fed GK rats with hyperlipidaemia showed increased vascular and systemic oxidative stress and impaired endothelial‐dependent vasodilatation. Metformin treatment significantly improved glycation, oxidative stress, CCL2 levels, NO bioavailability and insulin resistance and normalized endothelial function in aorta.CONCLUSION AND IMPLICATIONSMetformin restores endothelial function and significantly improves NO bioavailability, glycation and oxidative stress in normal and high‐fat fed GK rats. This supports the concept of the central role of metformin as a first‐line therapeutic to treat diabetic patients in order to protect against endothelial dysfunction associated with type 2 diabetes mellitus.
Heat shocks enhance procollagen type I and III expression in fibroblasts in ex vivo human skin
Authors: Dams S. D. , de Liefde‐van Beest M. , Nuijs A. M. , Oomens C. W. J. , Baaijens F. P. T. 
Published: January 2011

Background: The well‐known characteristics of aging skin are the development of fine lines and wrinkles, but changes in skin tone, skin texture, thickness and moisture content are also aspects of aging. Rejuvenation of the skin aims at reversing the signs of aging and can be established in the epidermis as well as in the dermis. Aged dermis, in fact, has a degenerated collagen matrix. To regenerate this matrix, fibroblasts need to be stimulated into synthesizing new collagen.Aims: In this study, the effects of heat shocks of different temperatures on human dermal fibroblasts in ex vivo skin on the expression of procollagen 1, procollagen 3, heat shock protein (hsp)27, hsp47, and hsp70 are investigated.Materials and methods: The heat shocks were applied on ex vivo skin samples by immersing the samples in heated phosphate‐buffered saline of 45 °C or 60 °C. Metabolic activity was measured and at similar time points propidium–iodide–calceine staining was performed to establish cell viability. Quantitative polymerase chain reaction (qPCR) was performed after the heat shock to determine gene expression levels relative to the reference temperature. Furthermore, PicroSirius Red and hematoxylin stainings were performed to visualize the collagen network and the cells.Results: The skin samples were shown to be viable and metabolically active. Histology indicated that the heat shocks did not influence the structure of the collagen network or cell appearance. qPCR results showed that in contrast to the 45 °C heat shock the 60 °C heat shock resulted in significant upregulations of procollagen type I and III, hsp70 and hsp47.Conclusion: A 60 °C, heat shock stimulates the human dermal fibroblasts in ex vivo skin to upregulate their procollagen type I and type III expression.
Is there any barrier impairment in sensitive skin?: a quantitative analysis of sensitive skin by mathematical modeling of transepidermal water loss desorption curves
Authors: Pinto Pedro , Rosado Catarina , Parreirão Catarina , Rodrigues Luis Monteiro 
Published: January 2011

Background/purpose: Sensitive skin is a vague, subjective and difficult to characterize affliction. It affects a large part of the population and is accompanied with great interest by the cosmetic industry. Some studies have suggested that sensitive skin is the result of impaired barrier function, which leads to the exposure of immune system cells and sensitive nerves, resulting in marked cutaneous responses to otherwise harmless stimuli. This study aimed to investigate the cutaneous barrier integrity of individuals with sensitive skin by a novel approach: a plastic occlusion stress test followed by measurement of transepidermal water loss (TEWL) desorption curves.Methods: The study was conducted in volunteers with sensitive skin in the hands and a control group with no sensitivity complaints. A previously developed mathematical model was adjusted to the TEWL data points and two parameters were calculated: dynamic water mass and the evaporation half‐life period.Results: Statistically significant differences have been detected in the parameters obtained in the sensitive skin group, which supports the thesis that individuals with an increased skin susceptibility have impaired barrier function.Conclusion: Whereas in the studies based in basal TEWL measurements only discrete differences were reported, the dynamic approach followed in this study provided unequivocal evidence of barrier impairment. The methodology enabled a more objective characterization of sensitive skin and can potentially be applied to the diagnosis/prediction of sensitivity; as well as the efficacy assessment of cosmetic products that are specifically designed to fulfill the needs of consumers with this skin condition.
DNA‐methylation profiling distinguishes malignant melanomas from benign nevi
Authors: Conway Kathleen , Edmiston Sharon N. , Khondker Zakaria S. , Groben Pamela A. , Zhou Xin , Chu Haitao , Kuan Pei Fen , Hao Honglin , Carson Craig , Berwick Marianne , Olilla David W. , Thomas Nancy E. 
Published: January 2011

SummaryDNA methylation, an epigenetic alteration typically occurring early in cancer development, could aid in the molecular diagnosis of melanoma. We determined technical feasibility for high‐throughput DNA‐methylation array‐based profiling using formalin‐fixed paraffin‐embedded tissues for selection of candidate DNA‐methylation differences between melanomas and nevi. Promoter methylation was evaluated in 27 common benign nevi and 22 primary invasive melanomas using a 1505 CpG site microarray. Unsupervised hierarchical clustering distinguished melanomas from nevi; 26 CpG sites in 22 genes were identified with significantly different methylation levels between melanomas and nevi after adjustment for age, sex, and multiple comparisons and with β‐value differences of ≥0.2. Prediction analysis for microarrays identified 12 CpG loci that were highly predictive of melanoma, with area under the receiver operating characteristic curves of >0.95. Of our panel of 22 genes, 14 were statistically significant in an independent sample set of 29 nevi (including dysplastic nevi) and 25 primary invasive melanomas after adjustment for age, sex, and multiple comparisons. This first report of a DNA‐methylation signature discriminating melanomas from nevi indicates that DNA methylation appears promising as an additional tool for enhancing melanoma diagnosis.
Effect of the duration of immunomodulatory therapy on the clinical features of recurrent episodes in Vogt–Koyanagi–Harada disease
Authors: Errera Marie‐Hélène , Fardeau Christine , Cohen David , Navarro Audrey , Gaudric Alain , Bodaghi Bahram , Westcott Mark , LeHoang Phuc 
Published: January 2011

Abstract.Purpose:  To evaluate the duration of immunomodulatory therapy (corticosteroids, immunosuppressive drugs) with regard to the rate of relapses and clinical features (exudative retinal detachment or anterior uveitis) in inflammatory episodes of Vogt–Koyanagi–Harada disease.Methods:  Data of all 42 patients diagnosed with acute uveitis associated with VKH disease during the period of January 2005 to December 2008 at the Pitié‐Salpêtrière Hospital or at the Lariboisière Hospital in Paris, France were extracted by chart review.Results:  There were 31 patients (73.8%) with episodes of recurrence and were included in the study. At the first recurrence, 81% (13 patients) of exudative retinal detachments (ERD) were associated with an initial immunomodulatory treatment conducted ≤6 months (3.76 months ± 2.67). Conversely, an initial treatment duration of >6 months was associated with anterior uveitis signs for 66% of patients (eight patients) with anterior first recurrence (p = 0.0061). On second episode of recurrence, 75% of patients (three patients) who developed exudative retinal detachment had been managed by immunomodulatory therapy for ≤6 months with the total duration of immunomodulatory treatment ≤6 months during previous inflammatory episodes. Conversely, all 16 patients who presented anterior uveitis with additional manifestations (optic disc oedema, macular oedema, vitritis and/or ‘Sunset glow’ fundus) have been treated for more than 6 months or treated during the initial occurrence lasting more than 9 months (p = 0.0035).Conclusions:  The duration of systemic corticosteroids (and/or immunosuppressive drug therapy) for ≤6 months at first and second recurrence was associated with features of further exudative retinal detachment instead of anterior uveitis in VKH disease.
The evidence of stand development stages in simulations by an individual-tree growth simulator
Authors: Huber Markus O. 
Published: January 2011

Individual-tree growth models have often been evaluated at the stand level in terms of stand increment or the development of stand density, but rarely in conceptual terms of natural stand dynamics. This study addresses the stand development stage concept developed for natural forests and shows how individual-tree growth models can be evaluated in this respect. For this purpose, the individual-tree growth simulator PrognAus was used to simulate the development of three sites for 2500 years, and a statistical classification model and a rule-based classification scheme were used to identify development stages in the output of the simulator. A comparison of the simulated stages with stages observed in a natural forest in terms of the stand volume and a comparison of the simulated stages with hypotheses from the literature in terms of volume, change of volume, and stand density were performed to determine if the simulations are consistent with the theory.
Tree species and soil nutrient profiles in old-growth forests of the Oregon Coast Range
Authors: Cross Alison , Perakis Steven S. 
Published: January 2011

Old-growth forests of the Pacific Northwest provide a unique opportunity to examine tree species – soil relationships in ecosystems that have developed without significant human disturbance. We characterized foliage, forest floor, and mineral soil nutrients associated with four canopy tree species (Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco), western hemlock (Tsuga heterophylla (Raf.) Sarg.), western redcedar (Thuja plicata Donn ex D. Don), and bigleaf maple (Acer macrophyllum Pursh)) in eight old-growth forests of the Oregon Coast Range. The greatest forest floor accumulations of C, N, P, Ca, Mg, and K occurred under Douglas-fir, primarily due to greater forest floor mass. In mineral soil, western hemlock exhibited significantly lower Ca concentration and sum of cations (Ca + Mg + K) than bigleaf maple, with intermediate values for Douglas-fir and western redcedar. Bigleaf maple explained most species-based differences in foliar nutrients, displaying high concentrations of N, P, Ca, Mg, and K. Foliar P and N:P variations largely reflected soil P variation across sites. The four tree species that we examined exhibited a number of individualistic effects on soil nutrient levels that contribute to biogeochemical heterogeneity in these ecosystems. Where fire suppression and long-term succession favor dominance by highly shade-tolerant western hemlock, our results suggest a potential for declines in both soil Ca availability and soil biogeochemical heterogeneity in old-growth forests.
Simulating the effectiveness of three potential management options to slow the spread of emerald ash borer (Agrilus planipennis) populations in localized outlier sites
Authors: Mercader Rodrigo J. , Siegert Nathan W. , Liebhold Andrew M. , McCullough Deborah G. 
Published: January 2011

The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a devastating, invasive insect pest of ash trees, Fraxinus spp., in North America. Using a simulation model, we evaluated three potential management options to slow the spread of A. planipennis in discrete outlier sites: (i) removing ash trees to reduce available host phloem resource, (ii) girdling ash trees to attract ovipositing female beetles and destroying the trees before larvae complete development, and (iii) applying a highly effective systemic insecticide. Simulations indicate that systemic insecticide applications provided the greatest reduction in the radial spread of A. planipennis. In simulations in which management options were applied only within a 300 m radius from the origin of the infestation, insecticide applications reduced the radial spread by 30% and larval consumption of ash phloem by 40% beyond the treated area. In contrast, girdling ash trees reduced the radial spread by 15% and larval consumption of ash phloem by 20% beyond the treated area. Both of these management options significantly reduced the spread of A. planipennis when treatments were applied 1 to 4 years after infestations were initiated. Reducing ash phloem by removing ash trees decreased population size within treated areas but did not reduce the radial spread, population size, or larval consumption of ash phloem beyond treated areas.
Contrasting the temporal dynamics of stand structure in even- and uneven-sized Picea abies dominated stands
Authors: Zenner Eric K. , Lähde Erkki , Laiho Olavi 
Published: January 2011

Although proposed as a means of increasing structural diversity in managed forests, the impact of single-tree selection on the temporal dynamics of three-dimensional structure has not been previously evaluated. Forest structural development in Picea-dominated stands was contrasted over 15 years in stem-mapped randomized plots in southern Finland that underwent either low thinning (creating the even-sized (ES) structure of a bell-shaped diameter distribution) or single-tree selection (maintaining the uneven-sized (UES) structure of a reverse-J-shaped distribution) through multiple harvest entries. Structure was quantified with nonspatial stand attributes (e.g., density) and indices that quantify spatially explicit relationships among neighboring trees (e.g., structural complexity index (SCI)). Over time, three-dimensional structure reflected differential tree growth and mortality, resulting in minor changes in tree composition, spatial pattern, and tree size differentiation and somewhat greater changes in the SCI. The third harvest entry simplified the forest structure in both structure types. However, structural metrics such as the variability of tree diameters, tree size differentiation, and the SCI recovered to preharvest levels within 2–4 years in UES plots, whereas no recovery was seen in the ES structure type. Single-tree selection was demonstrated to perpetuate the uneven-sized structure associated with natural nonpyrogenic Picea-dominated forests.
Predictions of wood density and module of elasticity of balsam fir (Abies balsamea) and black spruce (Picea mariana) from near infrared spectral analyses
Authors: Xu Qinghua , Qin Menghua , Ni Yonghao , Defo Maurice , Dalpke Barbara , Sherson Gail 
Published: January 2011

The predictions of properties for wood disc average are seldom reported, and they are important for sorting out logs based on their quality. The minimum near infrared (NIR) spectra required to predict wood disc average properties would also be of critical importance. In this study, calibration and prediction models for wood disc average properties were developed using NIR spectral data for balsam fir (Abies balsamea (L.) Mill.) and black spruce (Picea mariana (Mill.) B.S.P.) samples collected from 14 different sites across Newfoundland, Canada. The calibration was done against area-weighted average wood properties determined by SilviScan. NIR spectra were collected in 18 mm increments from the radial–longitudinal face of green and oven-dried samples. Results showed that using NIR spectra from three spots per wood strip was sufficient for the modeling and prediction for density and module of elasticity (MOE). The coefficients of determination ranged from 0.76 (MOE of green wood samples) to 0.88 (density of oven-dried wood samples). However, the microfibril angle (MFA) cannot be well predicted from either green wood or oven-dried wood NIR spectra. Our results further showed that the NIR spectra collected from oven-dried wood samples gave better calibration and prediction than those collected from green wood samples.
Changes in litter and dead wood loads following tree death beneath subalpine conifer species in northern Colorado
Authors: Bigler Christof , Veblen Thomas T. 
Published: January 2011

Litter and dead wood affect important processes in forest ecosystems such as nutrient and carbon cycling and are key influences on biodiversity and fire behavior. Increased tree mortality rates in western North America associated with climate trends and increased bark beetle activity highlight the need to better understand the dynamics of litter and dead wood following tree death. For eight old-growth stands in a subalpine forest landscape in northern Colorado (USA), we compared litter and dead wood loads beneath more than 200 dead and live Engelmann spruce (Picea engelmannii Parry ex Engelm.), subalpine fir (Abies lasiocarpa (Hook.) Nutt.), and lodgepole pine (Pinus contorta Douglas ex Loudon). The dynamics of litter and dead wood were analyzed using chronosequences of tree death dates over >100 years that we determined from tree rings. Immediately following tree death, high loads of litter accumulated, particularly for the biggest spruces, which accumulated 10 times more litter than live spruces (five times more for fir, two times more for pine). We estimated a higher decay rate of litter for spruce (half-life of four years) than for pine (15 years) and fir (19 years). The accumulation rates for dead wood following tree death were highly variable among trees, but maximum accumulation was attained during the first 50–60 years.
FILTER POSITION IN NETWORKS OF SUBSTITUTION PROCESSORS DOES NOT MATTER
Authors: MONTORO FERNANDO ARROYO , CASTELLANOS JUAN , MITRANA VICTOR , SANTOS EUGENIO , SEMPERE JOSE M. 
Published: January 2011

It is known ([4]) that moving the filters from the nodes to the edges in accepting hybrid networks of evolutionary processors does not decrease the computational power of the model which equals that of a Turing machine. A direct and time complexity preserving simulation is presented in [1]. All three types of processors (substitution, insertion, deletion) are essentially used in this simulation. In this note we prove that such a direct simulation between networks containing substitution nodes only still exists.
Studies on Mechanism of Action of Anticancer Peptides by Modulation of Hydrophobicity Within a Defined Structural Framework
Authors: Huang Yi-bing , Wang Xiao-fei , Wang Hong-ye , Liu Yu , Chen Yuxin 
Published: January 2011

Abstract
In the present study, the hydrophobicity of a 26-residue α-helical peptide (peptide P) was altered to study the effects of peptide hydrophobicity on the mechanism of action of cationic anticancer peptides. Hydrophobicity of the nonpolar face of the peptides was shown to correlate with peptide helicity. The self-association ability of peptides in aqueous environment, determined by the reversed-phase high performance liquid chromatography temperature profiling, showed strong influence on anticancer activity. The peptide analogues with greater hydrophobicity showed stronger anticancer activity determined by IC50 values with a necrotic-like membrane disruption mechanism. Peptide analogues exhibited high specificity against cancer cells and much higher anticancer activity than widely-used anticancer chemical drugs. The mechanism of action of anticancer peptides was also investigated. The hydrophobicity of peptides plays a crucial role in the mechanism of action against cancer cells, which could present a way, using a de novo design approach, to create anticancer peptides as potential therapeutics in clinical practices. Mol Cancer Ther; 10(3); 416–26. ©2011 AACR.
Comprehensive Evaluation of the Contribution of X Chromosome Genes to Platinum Sensitivity
Authors: Gamazon Eric R. , Im Hae Kyung , O'Donnell Peter H. , Ziliak Dana , Stark Amy L. , Cox Nancy J. , Dolan M. Eileen , Huang Rong Stephanie 
Published: January 2011

Abstract
Using a genome-wide gene expression data set generated from Affymetrix GeneChip Human Exon 1.0ST array, we comprehensively surveyed the role of 322 X chromosome gene expression traits on cellular sensitivity to cisplatin and carboplatin. We identified 31 and 17 X chromosome genes whose expression levels are significantly correlated (after multiple testing correction) with sensitivity to carboplatin and cisplatin, respectively, in the combined HapMap CEU (Utah residents with ancestry from northern and western Europe) and YRI (Yoruba in Ibahan, Nigeria) populations (false discovery rate, FDR &lt; 0.05). Of those, 14 overlap for both cisplatin and carboplatin. Using an independent gene expression quantification method, the Illumina Sentrix Human-6 Expression BeadChip, measured on the same HapMap cell lines, we found that 4 and 2 of these genes are significantly associated with carboplatin and cisplatin sensitivity, respectively, in both analyses. Two genes, CTPS2 and DLG3, were identified by both genome-wide gene expression analyses as correlated with cellular sensitivity to both platinating agents. The expression of DLG3 gene was also found to correlate with cellular sensitivity to platinating agents in NCI-60 cancer cell lines. In addition, we evaluated whether the expression of X chromosome genes contributed to the observed differences in sensitivity to the platinums between CEU and YRI-derived cell lines. Of the 34 distinct genes significantly correlated with either carboplatin or cisplatin sensitivity, 14 are differentially expressed (defined as P &lt; 0.05) between CEU and YRI. Thus, sex chromosome genes play a role in cellular sensitivity to platinating agents and differences in the expression level of these genes are an important source of variation that should be included in comprehensive pharmacogenomic studies. Mol Cancer Ther; 10(3); 472–80. ©2011 AACR.