bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression analysis of E-cadherin, Slug and GSK3β in invasive ductal carcinoma of breast
Authors: Prasad Chandra P , Rath Gayatri , Mathur Sandeep , Bhatnagar Dinesh , Parshad Rajinder , Ralhan Ranju 
Published: September 2009

Abstract

Background
Cancer progression is linked to a partially dedifferentiated epithelial cell phenotype. The signaling pathways Wnt, Hedgehog, TGF-β and Notch have been implicated in experimental and developmental epithelial mesenchymal transition (EMT). Recent findings from our laboratory confirm that active Wnt/β-catenin signaling is critically involved in invasive ductal carcinomas (IDCs) of breast.

Methods
In the current study, we analyzed the expression patterns and relationships between the key Wnt/β-catenin signaling components- E-cadherin, Slug and GSK3β in IDCs of breast.

Results
Of the 98 IDCs analyzed, 53 (54%) showed loss/or reduced membranous staining of E-cadherin in tumor cells. Nuclear accumulation of Slug was observed in 33 (34%) IDCs examined. Loss or reduced level of cytoplasmic GSK3β expression was observed in 52/98 (53%) cases; while 34/98 (35%) tumors showed nuclear accumulation of GSK3β. Statistical analysis revealed associations of nuclear Slug expression with loss of membranous E-cadherin (p = 0.001); nuclear β-catenin (p = 0.001), and cytoplasmic β-catenin (p = 0.005), suggesting Slug mediated E-cadherin suppression via the activation of Wnt/β-catenin signaling pathway in IDCs. Our study also demonstrated significant correlation between GSK3β nuclear localization and tumor grade (p = 0.02), suggesting its association with tumor progression.

Conclusion
The present study for the first time provided the clinical evidence in support of Wnt/β-catenin signaling upregulation in IDCs and key components of this pathway - E-cadherin, Slug and GSK3β with β-catenin in implementing EMT in these cells.
Hemoglobin levels and anemia evaluation during pregnancy in the highlands of Tibet: a hospital-based study
Authors: Xing Yuan , Yan Hong , Dang Shaonong , Zhuoma Bianba , Zhou Xiaoyan , Wang Duolao 
Published: September 2009

Abstract

Background
Anemia is regarded as a major risk factor for unfavorable pregnancy outcomes, but there have been no previous studies describing the pattern of hemoglobin concentration during pregnancy in Tibet and the relationship between altitude and Hb concentration in the pregnant women living in Tibet still has not been clearly established. The main objectives of this study were to study the hemoglobin levels and prevalence of anemia among pregnant women living in the highlands of Tibet and to evaluate potential associations of hemoglobin and anemia with women's characteristics.

Methods
The hospital-based study was conducted in 380 pregnant women. Their blood samples were tested and related sociodemographic information was collected. Multiple linear regression model and multiple logistic regression model were used to assess the association of pregnant women's characteristics with hemoglobin level and the occurrence of anemia. Centers for Disease Control (CDC), Dirren et al. and Dallman et al. methods were used to adjust the hemoglobin measurements based on altitude for estimating the prevalence of anemia.

Results
The mean hemoglobin concentration was 127.6 g/L (range: 55.0-190.0 g/L). Prevalence rate of anemia in this study was 70.0%, 77.9% and 41.3%, respectively for three altitude-correction methods for hemoglobin (CDC method, Dirren et al. method, and Dallman et al. method). Gestational age, ethnicity, residence and income were significantly associated with the hemoglobin concentration and prevalence of anemia in the study population. Specially, the hemoglobin concentration of pregnant women decreased with increase in gestational age.

Conclusion
The hemoglobin level was low and prevalence rate of anemia was high among pregnant women in Lhasa, Tibet. Gestational age, ethnicity, residence and income were found to be significantly associated with the hemoglobin level and the occurrence of anemia in the study population.
Use of the slide positivity rate to estimate changes in malaria incidence in a cohort of Ugandan children
Authors: Jensen Trevor P , Bukirwa Hasifa , Njama-Meya Denise , Francis Damon , Kamya Moses R , Rosenthal Philip J , Dorsey Grant 
Published: September 2009

Abstract

Background
As malaria control efforts intensify, it is critical to monitor trends in disease burden and measure the impact of interventions. A key surveillance indicator is the incidence of malaria. Yet measurement of incidence is challenging. The slide positivity rate (SPR) has been used as a surrogate measure of malaria incidence, but limited data exist on the relationship between SPR and the incidence of malaria.

Methods
A cohort of 690 children aged 1-10 years at enrollment were followed for all their health care needs over a four-year period in Kampala, Uganda. All children with fever underwent laboratory testing, allowing us to measure the incidence of malaria and non-malaria fevers. A formula was derived to estimate relative changes in the incidence of malaria (rΔIm) based on changes in the SPR and the assumption that the incidence of non-malaria fevers was consistent over time. Observed and estimated values of rΔIm were compared over two, six, and 12 month time intervals after restricting the analysis to children contributing observation time between the ages of 4-10 years to control for aging of the cohort.

Results
Over the four-year observation period the incidence of malaria declined significantly from 0.93 episodes per person-year in 2005 to 0.39 episodes per person-year in 2008 (p < 0.0001) and the incidence of non-malaria fevers declined significantly from 2.31 episodes per person-year in 2005 to 1.31 episodes per person-year in 2008 (p < 0.0001). Younger age was associated with a significantly greater incidence of malaria and the incidence of malaria was significantly higher during seasonal peaks occurring each January-February and May-June. Changes in SPR produced reasonably accurate estimates of rΔIm over all time intervals. The average absolute difference in observed and estimated values of rΔIm was lower for six-month intervals (0.13) than it was for two-month (0.21) or 12 month intervals (0.21).

Conclusion
Changes in SPR provided a useful estimate of changes in the incidence of malaria in a well defined cohort; however, a gradual decline in the incidence of non-malaria fevers introduced some bias in these estimates.
Expression of cartilage-derived morphogenetic protein in human intervertebral discs and its effect on matrix synthesis in degenerate human nucleus pulposus cells
Authors: Le Maitre Christine L , Freemont Anthony J , Hoyland Judith A 
Published: September 2009

Abstract
Introduction
Loss of intervertebral disc (IVD) matrix and ultimately disc height as a result of 'degeneration' has been implicated as a major cause of low back pain (LBP). The use of anabolic growth factors as therapies to regenerate IVD matrix, hence restoring disc height and thus reversing degenerative disc disease, has been suggested. Cartilage-derived morphogenetic protein (CDMP) is a growth factor which stimulates proteoglycan production in chondrocyte-like cells and thus could be a useful growth factor for LBP therapies. However, little is known about the expression of CDMP or its receptor in human IVD, nor its effects on human disc cells.

Methods
Using immunohistochemistry we investigated the localisation of CDMP in non-degenerate and degenerate human IVDs. Additionally, we investigated the effect of CDMP on aggrecan and type II collagen gene expression and proteoglycan synthesis in nucleus pulposus (NP) cells derived from degenerate IVDs.

Results
We demonstrated that CDMP 1 and 2 were expressed in the non-degenerate and degenerate IVD, particularly in cells of the NP. A small decrease in the number of CDMP 1 and 2 immunopositive cells was seen with degeneration. Treatment of human NP cells, (derived from degenerate IVD), with CDMP showed an increase in aggrecan and type II collagen gene expression and increased production of proteoglycan (GAGs).

Conclusions
The data suggests that CDMP may be a useful growth factor to stimulate proteoglycan production in the human degenerate IVD and hence the repair of the extracellular matrix.
Perioperative indocyanine green clearance is predictive for prolonged intensive care unit stay after coronary artery bypass grafting - an observational study
Authors: Sander Michael , Spies Claudia D , Berger Katharina , Schröder Torsten , Grubitzsch Herko , Wernecke Klaus D , von Heymann Christian 
Published: September 2009

Abstract
Introduction
During cardiac surgery with cardiopulmonary bypass (CPB) haemodilution occurs. Hepatic dysfunction after CPB is a rare, but serious, complication. Clinical data have validated the plasma-disappearance rate of indocyanine green (PDR ICG) as a marker of hepatic function and perfusion. Primary objective of this analysis was to investigate the impact of haemodilutional anaemia on hepatic function and perfusion by the time course of PDR ICG and liver enzymes in elective CABG surgery. Secondary objective was to define predictors of prolonged ICU treatment like decreased PDR ICG after surgery.

Methods
60 Patients were subjected to normothermic CPB with predefined levels of haemodilution anaemia (haemotacrit (Hct) of 25% versus 20% during CPB). Hepatic function and perfusion was assessed by PDR ICG, plasma levels of aspartate aminotransferase (ASAT) and α-GST. Prolonged ICU treatment was defined as treatment ≥ 48 hours.

Results
Logistic regression analysis showed that all postoperative measurements of PDR ICG (P < 0.01), and the late postoperative ASAT (P < 0.01) measurement were independent risk factors for prolonged ICU treatment. The predictive capacity for prolonged ICU treatment was best of the PDR ICG one hour after admission to the ICU. Furthermore, the time course of PDR ICG as well as ASAT and α-GST did not differ between groups of haemodilutional anaemia.

Conclusions
Our study provides evidence that impaired PDR ICG as a marker of hepatic dysfunction and hypoperfusion may be a valid marker of prolonged ICU treatment. Additionally this study provides evidence that haemodilutional anaemia to a Hct of 20% does not impair hepatic function and perfusion.

Trial registration
[ISRCTN35655335]
Genome-wide deletion mutant analysis reveals genes required for respiratory growth, mitochondrial genome maintenance and mitochondrial protein synthesis in Saccharomyces cerevisiae
Authors: Merz Sandra , Westermann Benedikt 
Published: September 2009

Abstract
Background
The mitochondrial respiratory chain produces metabolic energy by oxidative phosphorylation. Biogenesis of the respiratory chain requires the coordinated expression of two genomes: the nuclear genome encoding the vast majority of mitochondrial proteins, and the mitochondrial genome encoding a handful of mitochondrial proteins. The understanding of the molecular processes contributing to respiratory chain assembly and maintenance requires the systematic identification and functional analysis of the genes involved.

Results
We pursued a systematic, genome-wide approach to define the sets of genes required for respiratory activity and maintenance and expression of the mitochondrial genome in yeast. By comparative gene deletion analysis we found an unexpected phenotypic plasticity among respiratory-deficient mutants, and we identified ten previously uncharacterized genes essential for respiratory growth (RRG1 through RRG10). Systematic functional analysis of 319 respiratory-deficient mutants revealed 16 genes essential for maintenance of the mitochondrial genome, 88 genes required for mitochondrial protein translation, and 10 genes required for expression of specific mitochondrial gene products. A group of mutants acquiring irreversible damage compromising respiratory capacity includes strains defective in assembly of the cytochrome c oxidase that were found to be particularly sensitive to aging.

Conclusions
These data advance the understanding of the molecular processes contributing to maintenance of the mitochondrial genome, mitochondrial protein translation, and assembly of the respiratory chain. They revealed a number of previously uncharacterized components, and provide a comprehensive picture of the molecular processes required for respiratory activity in a simple eukaryotic cell.
Reverse-engineering the Arabidopsis thaliana transcriptional network under changing environmental conditions
Authors: Carrera Javier , Rodrigo Guillermo , Jaramillo Alfonso , Elena Santiago F 
Published: September 2009

Abstract
Background
Understanding the molecular mechanisms plants have evolved to adapt their biological activities to a constantly changing environment is an intriguing question and one that requires a systems biology approach. Here we present a network analysis of genome-wide expression data combined with reverse-engineering network modeling to dissect the transcriptional control of Arabidopsis thaliana. The regulatory network is inferred by using an assembly of microarray data containing steady-state RNA expression levels from several growth conditions, developmental stages, biotic and abiotic stresses, and a variety of mutant genotypes.

Results
We show that the A. thaliana regulatory network has the characteristic properties of hierarchical networks. We successfully applied our quantitative network model to predict the full transcriptome of the plant for a set of microarray experiments not included in the training dataset. We also used our model to analyze the robustness in expression levels conferred by network motifs such as the coherent feed-forward loop. In addition, the meta-analysis presented here has allowed us to identify regulatory and robust genetic structures.

Conclusions
These data suggest that A. thaliana has evolved high connectivity in terms of transcriptional regulation among cellular functions involved in response and adaptation to changing environments, while gene networks constitutively expressed or less related to stress response are characterized by a lower connectivity. Taken together, these findings suggest conserved regulatory strategies that have been selected during the evolutionary history of this eukaryote.
Bridging the gap between systems biology and medicine
Authors: Clermont Gilles , Auffray Charles , Moreau Yves , Rocke David M , Dalevi Daniel , Dubhashi Devdatt , Marshall Dana R , Raasch Peter , Dehne Frank , Provero Paolo , Tegner Jesper , Aronow Bruce J , Langston Michael A , Benson Mikael 
Published: September 2009

AbstractSystems biology has matured considerably as a discipline over the last decade, yet some of the key challenges separating current research efforts in systems biology and clinically useful results are only now becoming apparent. As these gaps are better defined, the new discipline of systems medicine is emerging as a translational extension of systems biology. How is systems medicine defined? What are relevant ontologies for systems medicine? What are the key theoretic and methodologic challenges facing computational disease modeling? How are inaccurate and incomplete data, and uncertain biologic knowledge best synthesized in useful computational models? Does network analysis provide clinically useful insight? We discuss the outstanding difficulties in translating a rapidly growing body of data into knowledge usable at the bedside. Although core-specific challenges are best met by specialized groups, it appears fundamental that such efforts should be guided by a roadmap for systems medicine drafted by a coalition of scientists from the clinical, experimental, computational, and theoretic domains.
Ignition of Contaminated Aluminum by Impact in Liquid Oxygen—Influence of Oxygen Purity
Authors: Werlen Etienne , Crayssac Frédéric , Longuet Olivier , Willot Fabien 
Published: September 2009

Abstract
Impact tests in liquid oxygen and oxygen enriched liquids have been conducted on aluminum foils (0.2 mm thick) used for heat exchangers of air separation units (ASUs). Some adaptations to the ASTM Standard D2512, “Standard Test Method for Compatibility of Materials with Liquid Oxygen,” have been done to ensure the good control of oxygen content in the cryogenic liquid and to get reproducible results in aluminum ignition with hydrocarbon coating. Modified striker pins with a cavity on the contact surface have been used. The vertical guiding and the centering of the striker pins have been ensured by using two machined guides. Test samples were three layers of aluminum foil, two corrugated and one flat, contaminated by various quantities of hexadecane. The criteria for the identification of aluminum ignition (positive tests) have been validated by performing Scanning electron microscope surface analysis on residuals of a few impact tests performed in copper cups. Criteria have also been defined to check that hexadecane combustion took place in negative tests. A sufficient number of tests have been performed to plot the probability of ignition of the aluminum samples as a function of the average thickness of hexadecane coating and as a function of the oxygen content in the cryogenic liquid varying from 50 % to above 99.95 %. The remaining part in the cryogenic liquid was nitrogen and 2.3 % argon except for one series of tests where the influence of the absence of argon could be identified. The results of these tests can be used to assess the risk of ignition of some aluminum exchangers or structures used in ASU.
Test Methods for Characterizing Air Void Systems in Portland Cement Pervious Concrete
Authors: Kevern John T. , Wang Kejin , Schaefer Vernon R. 
Published: September 2009

Abstract
Portland cement pervious concrete is becoming a common tool for stormwater management across the United States. The air void system in pervious concrete is particularly important because of its effect on stormwater infiltration, concrete strength, and long-term durability. However, currently the concrete industry lacks standardized testing techniques for characterizing air void systems in pervious concrete. In this paper a series of air system characterization tests performed during a field placement of pervious concrete is detailed, and the test results are compared. Fresh pervious concrete samples from two delivered mixtures were evaluated using pressure, volumetric, Chace, and air void analyzer air test methods. The hardened concrete samples were tested for water-permeable void content, water permeability, air voids (using ASTM Standard C457 method), and freeze-thaw durability (using ASTM Standard C666A method). Based on the results of the study, determination of air systems for the freeze-thaw protection of pervious concrete is proposed.
Fracture Mechanics of Brittle Ceramics - 30 Years of Progress
Authors: Bradt RC 
Published: September 2009

The application of fracture mechanics to advanced technical ceramics was initiated nearly 30 years ago. It was heralded by an international conference at the Pennsylvania State University in 1973. Unbridled optimism prevailed as many believed that the coupling of fracture mechanics with ceramics would enable high temperature advanced ceramics to find extensive structural applications. Unfortunately, there were a number of barriers to the use of ceramics as structural materials, even with the application of fracture mechanics.
The use of brittle ceramics in structural applications faced major challenges. These included: (1) the absence of a reliable data base of materials properties, (2) the lack of appropriate standards for the determination of the properties of these materials, (3) a lack of any rational, fracture mechanics based design methodology for brittle ceramics, and (4) the high costs of producing and utilizing structural parts from advanced ceramics. These were serious deficiencies that inhibited the achievement of successful applications of ceramics.
Fracture mechanics tests provided a basis for the design methodology and also provided understanding of the basics of the fracture process in brittle ceramics. It informed the engineering community that ceramic fracture toughnesses were low, &lt; 10 MPa√m and that there were serious problems with slow crack growth and fatigue. The presence of rising R-curve behavior was observed and related to the crack tip's following wake region. Cyclic fatigue was confirmed to exist and related to the presence of a rising R-curve.
Today, the promise of structural ceramics remains mostly unfulfilled, except for a few niche applications that are nonetheless encouraging. In addition, there have been significant advances in the properties and integrity of structural ceramics over the past three decades. Advanced structural ceramics are better than ever. This can be attributed to the use of fracture mechanics concepts to identify the microstructural processing defects and then improve the processing methodology to eliminate those defects. There have also been major advances in the development of standards applied to ceramics in which ASTM has played a major role. Unfortunately, we still have not learned to design with brittle ceramics and the cost of their utilization in structural applications remains prohibitively high.
Application of Quantitative Fractography to the Characterization of R-Curve Behavior
Authors: Mecholsky JJ , Hill TJ , Chen Z 
Published: September 2009

The objective of this work is to demonstrate the applicability of quantitative fractography and fractal analysis to fracture processes in materials that exhibit R-curve behavior. In-situ toughened silicon nitride and baria-silica glass ceramics are used as model materials to demonstrate the effect of changes in morphology on toughness. These two tools, i.e., quantitative fracture surface analysis and fractal geometry, provide a new way of quantitatively assessing the mechanisms of toughening due to elongated grains and changes in microstructure.
For example, in silicon nitride the R-curve behavior only has an effect when the crack sizes are larger than about 30 micrometers. In applications where small cracks are expected, i.e., in bearing applications and for other well-polished surface finishes, R-curve materials may not be desirable.
In another example, 3BaO•5SiO2 glass ceramics were fabricated with crystals of aspect ratios (AR) of 1.4, 3.6 and 8.1. Based on fractal analysis, fractography and other accumulated data, it was shown that there was a statistical difference in the toughening behavior between materials with AR = 1.4 & 3.6, as compared to the material with AR = 8.1. The fractal dimensional increment was used to provide a method for determining the amount of toughening increase over that due to crack deflections as 0.4-0.6 MPam1/2. The implication of these results for the fracture process of toughened materials and the role of microstructure are discussed and explained in terms of material design.