bluuebunny/crossref_metadata_2025 huggingface dataset:
von Willebrand factor abnormalities in aortic valve stenosis: Pathophysiology and impact on bleeding
Authors: Sponga Sandro , Pontara Elena , Cattini Maria Grazia , Basso Cristina , Thiene Gaetano , Cella Giuseppe , Daidone Viviana , Gerosa Gino , Pagnan Antonio , Casonato Alessandra
Published: May 2011

Acquired von Willebrand syndrome (AVWS) may complicate severe aortic valve stenosis, due to a reduction in the haemostatically more efficient large von Willebrand factor (VWF) multimers. This study was designed to analyse the relevance of VWF abnormalities and haemorrhagic diathesis in severe aortic valve stenosis. Forty-one consecutive patients undergoing valve replacement were investigated: seven had minor bleeding symptoms in their recent history; 10 (24.3%) had a reduced VWF collagen binding (VWF:CB) to VWF antigen ratio, and 33 (80.5%) had a decrease in large VWF multimers. The shortage of large multimers was not associated with any accumulation of small VWF multimers (apparently ruling out any increased VWF proteolysis), nor was there any increase in VWF propeptide, which excludes a shorter VWF survival. The risk of developing VWF abnormalities was higher in patients with rheumatic valve disease than in degenerative cases (p=0.025) and in valves with <50% of residual endothelial cells (p=0.004). Bleeders differed from non-bleeders in that they had a higher mean transvalvular gradient and a more marked decrease in large VWF multimers. VWF abnormalities did not exacerbate peri-operative blood loss, however – a finding consistent with the full correction of these VWF abnormalities, seen already on the first postoperative day and persisting for up to six months after surgery. According to the data obtained in our cohort of patients VWF abnormalities are common in severe aortic stenosis, particularly in cases of rheumatic valve disease, but loss of the largest multimers does not seem to cause clinical bleeding in most patients.
Observing Climate at High Elevations Using United States Climate Reference Network Approaches
Authors: Palecki Michael A. , Groisman Pavel Ya.
Published: May 2011

The U.S. Climate Reference Network (USCRN) was deployed between 2001 and 2008 for the purpose of yielding high-quality and temporally stable in situ climate observations in pristine environments over the twenty-first century. Given this mission, USCRN stations are engineered to operate largely autonomously with great reliability and accuracy. A triplicate approach is used to provide redundant measurements of temperature and precipitation at each location, allowing for observations at a specific time to be compared for quality control. This approach has proven to be robust in the most extreme environments, from extreme cold (−49°C) to extreme heat (+52°C), in areas of heavy precipitation (4700 mm yr−1), and in locations impacted by strong winds, freezing rain, and other hazards. In addition to a number of stations enduring extreme winter environments in Alaska and the northern United States, seven of the USCRN stations are located at elevations over 2000 m, including stations on Mauna Loa, Hawaii (3407 m) and on Niwot Ridge above Boulder, Colorado (2996 m). The USCRN temperature instruments and radiation shield have also been installed and run successfully at a station on the Quelccaya Ice Cap in Peru (5670 m). This paper reviews the performance of the USCRN station network during its brief lifetime and the potential utility of its triplicate temperature instrument configuration for measuring climate change at elevation.
Financial Regulation
Authors: Barrell Ray , Davies E. Phillip
Published: May 2011

The financial crisis that engulfed the world in 2007 and 2008 has led to a wave of re-regulation and discussion of further regulation that has culminated in the proposals from the Basel Committee as well as those in the Vickers Committee report on Banking Regulation and Financial Crises. This issue of the Review contains a number of papers on Banking Regulation, covering many aspects of the debate, and we can put that debate in perspective through these papers and also by discussing our work on the relationship between bank size and risk taking, which is reported in Barrell et al. (2011). We addressed the causes of the crisis in the October 2008 Review, and began to look at the costs and benefits of bank regulation in Barrell et al. (2009). In that paper we argued that we needed to know the causes of crises and whether the regulators could do anything to affect them before we discussed new regulations. It is now generally agreed that increasing core capital reduces the probability of a crisis occurring, and most changes in regulation that are being discussed see this as the core of their toolkit. The work by the Institute macro team in Barrell et al. (2009) and in Barrell, Davis, Karim and Liadze (2010) was the first to demonstrate that there was a statistically important role for capital in defending against the probability of a crisis occurring, and our findings were widely used in the policy community in the debate over reform.
World Overview: Oil Prices and the Fiscal Stance
Authors: Holland Dawn , Barrell Ray , Delannoy Aurélie , Fic Tatiana , Hurst Ian , Orazgani Ali , Paluchowski Paweł , Whitworth Rachel
Published: May 2011

At the global level, GDP growth accelerated to 1.2 per cent in the final quarter of 2010 according to NIESR estimates — largely driven by a sharp rise in domestic demand in China, which more than offset a slowdown in world trade growth that originated in the US. The economic recovery in the advanced economies remains lacklustre. The sharp rise in the oil price in recent months has exacerbated the effects on output of the protracted downturn in global investment and a tighter fiscal policy stance, at least in Europe. High commodity prices will push inflation in the OECD close to 3 per cent both this year and next. At the global level we expect GDP growth to moderate from an estimated 5.2 per cent in 2010 to just below 4½ per cent per annum in 2011–12, with around half of this slowdown attributable to the effects of the increase in oil prices between October 2010 and April 2011. The key assumptions underlying this forecast are discussed in Appendix A, with our forecasts for key macro variables in 40 major economies detailed in Appendix B.
Prospects for the UK Economy
Authors: Kirby Simon , Barrell Ray , Whitworth Rachel
Published: May 2011

The performance of the UK economy has deteriorated markedly since autumn 2010. The volatility of output due to the adverse weather experienced last winter masks the underlying weakness in the UK economy. The Office for National Statistics (ONS) preliminary estimate of GDP suggests the underlying level of output has been flat since the third quarter of 2010. We expect the economy to grow from the second quarter of this year onwards, as we can see from figure 1, but we continue to expect this growth to be relatively weak. We expect GDP growth of 1.4 per cent per annum this year, rising to 2 per cent in 2012.
Real House Prices in the UK
Authors: Barrell Ray , Kirby Simon , Whitworth Rachel
Published: May 2011

The housing market plays a fundamental role in the economy, and its functioning affects both consumer welfare and economic stability, as the recent crisis has made clear. Research by Barrell et al. (2010) shows that house prices are a key determinant of financial crisis probabilities in OECD economies, and contribute significantly towards systemic banking risk. This must lead the regulator to assess carefully the role of the housing market in this relationship, and if necessary impose regulatory restrictions on the market so as to ensure it functions in a way that reflects the best interests of the economy. In this note we look at the evolution of real house prices in the UK, noting that they have a strong cyclical pattern. We then look at the factors that might affect the evolution of real house prices, and we estimate a dynamic equation describing those prices. After considering a wide set of factors, we demonstrate that there is little role for the supply of housing relative to the number of households. This may be because the ratio of these two variables has been relatively constant over the past thirty years. We show that real borrowing costs, real incomes and the loan-to-income ratio are significant factors determining the long-run path of real house prices, and that front loading problems from high short-term nominal interest rates affect the path of adjustment. Overvaluations can persist for years, and we would judge that real house prices are currently fundamentally overvalued by around 10 per cent. If loan-to-income ratios are reduced then the fundamental overvaluation will increase, and such a policy will put further downward pressure on real house prices.
The Banking Sector and Recovery in the EU Economy
Authors: Barrell Ray , Fic Tatiana , Gerald John Fitz , Orazgani Ali , Whitworth Rachel
Published: May 2011

Banks within Europe have become larger and more international as Europe has moved towards a unified financial services market, but this trend has been reversed since the crisis. In order to establish the effect of these structural changes on output in Europe, we use a micro data set to investigate the impact of size (as measured by asset size) on banks' net interest margins. We show that larger banks offer lower borrowing costs for firms, which raises sustainable output. We then use NiGEM to look at the impact of banks becoming smaller and moving back into their home territory. We investigate the impacts on output according to country size, showing that the effects are generally larger in small countries, and also larger in economies that are more dependent on bank finance for their business investment decisions.
Strategies for Increasing Advanced Placement Participation for Underrepresented Students: Barriers, Practices, and Positive Outcomes
Authors: Flores Sergio , Gomez Martin O.
Published: May 2011

Some school leaders have viewed programs such as Advanced Placement (AP) as an attractive option to resolve the ongoing achievement gap problem. However, the ongoing debate in the field about maintaining the ostensible purity of the AP program versus diluting it with program expansion has hindered the full utilization of AP classes to close the achievement gap among student populations. School staff must stop buying into the notion that AP is only for the top students. The paradigm shift to opening up greater access to AP courses can only occur if school leaders support the active expansion of the AP program by creating the needed infrastructure to prepare students for AP rigor. In addition to presenting the authors’ reasons, the barriers they faced, the best practices that they have developed, and the schoolwide increased student achievement based on state measures, the authors present how AP expansion provides equitable and challenging educational opportunities for all students.
Graft Uptake Rates with Isoamyl‐2‐Cyanoacrylate in Myringoplasty Procedures
Authors: Deenadayal Dasari Samuel , Neeli Ajay Kumar , Patel Saif Hameed
Published: May 2011

Objective

To assess graft uptake rates with the use of cyanoacrylate adhesives in myringoplasty procedures.

Study Design

Case series with chart review.

Setting

Tertiary care center.

Subjects and Methods

Five hundred forty‐two patients selected with safe central perforations were divided into 4 groups based on perforation size and each divided into 2 subgroups depending on the presence or absence of preexisting pathology on the remnant tympanic membrane. Myringoplasty without ossicular reconstruction was done postaurally or by transcanal approach, with inlay graft placed and adhesive applied. Ear pack was removed on the seventh postoperative day. Graft uptake rates, graft uptake time (neotympanum intact and mobile), and postoperative sequelae were noted.

Results

Graft uptake was about 99% at 3 months postsurgery. Residual perforation was seen in 2 patients in group 2 and 1 in group 4 and thinned‐out tympanum in 1 patient in group 4. Mean uptake time was 21 days. Neotympanum mobility was sluggish in 9 cases postoperatively in group 4 and in 2 cases in group 3. Patients with successful (neotympanum intact and mobile) graft uptake showed significant improvement. Postoperative inflammatory signs in the external auditory canal were seen in 3 cases.

Conclusion

Cyanoacrylate use in myringoplasty obtains graft uptake rates of 99% compared with most studies, which report 80% to 90%. This also allows removal of the pack by the seventh day, allowing close follow‐up of the graft and less patient discomfort. Importantly, it has not interfered with the formation of the neotympanum or compromised hearing improvement.
Quantitative and Qualitative Analyses of the Clock Drawing Test in Mild Cognitive Impairment and Alzheimer Disease: Evaluation of a Modified Scoring System
Authors: Parsey Carolyn M. , Schmitter-Edgecombe Maureen
Published: May 2011

The clock drawing test (CDT) has been used as a screening tool for identifying cognitive decline in individuals with Alzheimer disease (AD) and other dementias but has not been extensively evaluated for categorizing individuals with mild cognitive impairment (MCI). This study used both an established quantitative scoring system and a revised scoring method based on qualitative error criteria developed by Rouleau et al to demonstrate the sensitivity of the CDT to MCI. Participants were 66 cognitively healthy older adult, 33 individuals with MCI, and 33 individuals with AD. Sensitivity analyses of the 2 clock drawing methods revealed that the Modified Rouleau scoring method was more sensitive to MCI than the original Rouleau scoring system. Conceptual, graphic, and spatial-planning difficulties were the most commonly committed errors on the CDT across all groups, and conceptual errors along with graphic difficulties were committed more often in the MCI group than the cognitively healthy control group. Participants in the AD group exhibited greater deficits in all error categories and significantly lower total CDT scores compared to both the MCI and older adult controls. Findings observed in this study suggest that qualitative observations of clock drawing errors can help increase sensitivity of the CDT to MCI and that use of a more detailed scoring system is necessary to differentiate individuals with MCI from cognitively healthy older adults.
Paradigms of school change
Authors: Wrigley Terry
Published: May 2011

This short paper points to some paradigm issues in the field of school development (leadership, effectiveness, improvement) and their relationship to social justice. It contextualises the dominant School Effectiveness and School Improvement models within neo-liberal marketisation, paying attention to their transformation through a ‘marriage of convenience’ in the early 1990s. It contrasts these with other models of school change based upon the desire for curricular or political reform. It proposes a shift of emphasis from the competitive school as the key entity to a close examination of the symbolic exchanges between school and the neighbourhood, particularly in areas of poverty, and the sense which teachers and students are able to make of each others’ lives and cultural reference points. In addition to Bourdieu’s concept of capitals, it will draw on Goffman as a theorist who combines symbolic interactionism with an understanding of institutional norms.
Late onset lupus nephritis in Chinese patients: Classified by the 2003 International Society of Nephrology and Renal Pathology Society system
Authors: Xu Y-X , Tan Y , Yu F , Zhao M-H
Published: May 2011

Aim: The aim of this study was to assess clinicopathological characteristics and outcomes of a cohort of Chinese patients with late onset lupus nephritis.

Methods: Clinical, pathological and outcome data for patients with late onset lupus nephritis (onset at age ≥50 years) and early onset lupus nephritis (onset at age ≤40 years) were retrospectively analyzed and compared.

Results: Among 271 patients with renal biopsy-proven lupus nephritis, 30 were identified as having late onset lupus nephritis and 241 were identified as having early onset lupus nephritis. Lower female predominance was observed in the late onset patients ( p = 0.06). The interval between presentation of lupus nephritis and diagnosis was significantly longer in the late onset group than in the early onset group ( p = 0.003). In comparison with early onset group, patients in the late onset group had significantly lower scores for endocapillary hypercellularity ( p = 0.041), subendothelial hyaline deposits ( p = 0.022) and glomerular leukocyte infiltration ( p = 0.032), but had significantly higher scores for tubular atrophy ( p = 0.037) and interstitial fibrosis ( p = 0.018). Regarding long-term survival and renal outcome, there was no significant difference between the two groups, although it seemed that the early onset group had a poorer renal outcome ( p = 0.077, hazard ratio (HR) = 3.909, 95% CI: 0.862–17.726).

Conclusions: Patients with late onset lupus nephritis were usually diagnosed later; they had milder active lesions and more severe chronic lesions in renal pathology. However, the renal outcome was similar between late and early onset patients.
Benefits from condition monitoring techniques: a case study on maintenance scheduling of ball grid array solder joints
Authors: You M-Y , Liu F , Meng G
Published: May 2011

In the recent decade, more and more efforts in the field of reliability engineering are targeted towards developing condition-based maintenance (CBM) techniques for improving system availability and reducing maintenance cost. To justify the increased condition monitoring cost in a CBM programme, it is necessary to benchmark the performance of a maintenance policy enhanced by condition monitoring techniques with that of the conventional preventive maintenance (PM) policies. However, such studies are very limited in literature. This article presents a comparative study on maintenance scheduling of ball grid array (BGA) solder joints in a maintenance policy enhanced by condition monitoring techniques (policy A) and a conventional PM policy (policy B). Driven by the practical characteristics of the degradation signals of BGAs, a two-phase treatment (stable phase and unstable phase) is adopted in policy A: statistical process control techniques are used on the initial stable condition monitoring data of BGAs to detect the shift from the stable phase to the unstable phase, and trigger a traditional PM policy within the unstable phase. Benefits of the condition monitoring techniques are demonstrated in terms of a nontrivial reduction of maintenance cost rate in policy A, compared with that in policy B. From anther perspective, the current study also demonstrates the feasibility of incorporating condition monitoring techniques with the conventional PM policies for improved maintenance performance. The modelling approaches herein are generic and can be directly applied for other systems with similar degradation processes, such as bearings, mills, and gears.
Toll-like receptor 7 (TLR7)–driven accumulation of a novel CD11c+ B-cell population is important for the development of autoimmunity
Authors: Rubtsov Anatoly V. , Rubtsova Kira , Fischer Aryeh , Meehan Richard T. , Gillis Joann Z. , Kappler John W. , Marrack Philippa
Published: May 2011

Females are more susceptible than males to many autoimmune diseases. The processes causing this phenomenon are incompletely understood. Here, we demonstrate that aged female mice acquire a previously uncharacterized population of B cells that we call age-associated B cells (ABCs) and that these cells express integrin αX chain (CD11c). This unexpected population also appears in young lupus-prone mice. On stimulation, CD11c+ B cells, both from autoimmune-prone and healthy strains of mice, secrete autoantibodies, and depletion of these cells in vivo leads to reduction of autoreactive antibodies, suggesting that the cells might have a direct role in the development of autoimmunity. We have explored factors that contribute to appearance of ABCs and demonstrated that signaling through Toll-like receptor 7 is crucial for development of this B cell population. We were able to detect a similar population of B cells in the peripheral blood of some elderly women with autoimmune disease, suggesting that there may be parallels between the creation of ABC-like cells between mice and humans.
Tumor necrosis factor-α enhances hyperbaric oxygen-induced visfatin expression via JNK pathway in human coronary arterial endothelial cells
Authors: Wang Bao-Wei , Lin Chiu-Mei , Wu Gong-Jhe , Shyu Kou-Gi
Published: May 2011

Background

Visfatin, a adipocytokine with insulin-mimetic effect, plays a role in endothelial angiogenesis. Hyperbaric oxygen (HBO) has been used in medical practice. However, the molecular mechanism of beneficial effects of HBO is poorly understood. We sought to investigate the cellular and molecular mechanisms of regulation of visfatin by HBO in human coronary arterial endothelial cells (CAECs).

Methods

Human CAECs were exposed to 2.5 atmosphere absolute (ATA) of oxygen in a hyperbaric chamber. Western blot, real-time polymerase chain reaction, and promoter activity assay were performed. In vitro glucose uptake and tube formation was detected.

Results

Visfatin protein (2.55-fold) and mRNA (2.53-fold) expression were significantly increased after exposure to 2.5 ATA HBO for 4 to 6 h. Addition of SP600125 and JNK siRNA 30 min before HBO inhibited the induction of visfatin protein. HBO also significantly increased DNA-protein binding activity of AP-1 and visfatin promoter activity. Addition of SP600125 and TNF-α monoclonal antibody 30 min before HBO abolished the DNA-protein binding activity and visfatin promoter activity induced by HBO. HBO significantly increased secretion of TNF-α from cultured human CAECs. Exogenous addition of TNF-α significantly increased visfatin protein expression while TNF-α antibody and TNF-α receptor antibody blocked the induction of visfatin protein expression induced by HBO. HBO increased glucose uptake in human CAECs as HBO and visfatin siRNA and TNF-α antibody attenuated the glucose uptake induced by HBO. HBO significantly increased the tube formation of human CAECs while visfatin siRNA, TNF-α antibody inhibited the tube formation induced by HBO.

Conclusions

HBO activates visfatin expression in cultured human CAECs. HBO-induced visfatin is mediated by TNF-α and at least in part through JNK pathway.
Evolution of an endofungal Lifestyle: Deductions from the Burkholderia rhizoxinica Genome
Authors: Lackner Gerald , Moebius Nadine , Partida-Martinez Laila P , Boland Sebastian , Hertweck Christian
Published: May 2011

Background

Burkholderia rhizoxinica is an intracellular symbiont of the phytopathogenic zygomycete Rhizopus microsporus, the causative agent of rice seedling blight. The endosymbiont produces the antimitotic macrolide rhizoxin for its host. It is vertically transmitted within vegetative spores and is essential for spore formation of the fungus. To shed light on the evolution and genetic potential of this model organism, we analysed the whole genome of B. rhizoxinica HKI 0454 - a type strain of endofungal Burkholderia species.

Results

The genome consists of a structurally conserved chromosome and two plasmids. Compared to free-living Burkholderia species, the genome is smaller in size and harbors less transcriptional regulator genes. Instead, we observed accumulation of transposons over the genome. Prediction of primary metabolic pathways and transporters suggests that endosymbionts consume host metabolites like citrate, but might deliver some amino acids and cofactors to the host. The rhizoxin biosynthesis gene cluster shows evolutionary traces of horizontal gene transfer. Furthermore, we analysed gene clusters coding for nonribosomal peptide synthetases (NRPS). Notably, B. rhizoxinica lacks common genes which are dedicated to quorum sensing systems, but is equipped with a large number of virulence-related factors and putative type III effectors.

Conclusions

B. rhizoxinica is the first endofungal bacterium, whose genome has been sequenced. Here, we present models of evolution, metabolism and tools for host-symbiont interaction of the endofungal bacterium deduced from whole genome analyses. Genome size and structure suggest that B. rhizoxinica is in an early phase of adaptation to the intracellular lifestyle (genome in transition). By analysis of tranporters and metabolic pathways we predict how metabolites might be exchanged between the symbiont and its host. Gene clusters for biosynthesis of secondary metabolites represent novel targets for genomic mining of cryptic natural products. In silico analyses of virulence-associated genes, secreted proteins and effectors might inspire future studies on molecular mechanisms underlying bacterial-fungal interaction.
Characterization of age-related gene expression profiling in bone marrow and epididymal adipocytes
Authors: Liu Li-Fen , Shen Wen-Jun , Ueno Masami , Patel Shailja , Kraemer Fredric B
Published: May 2011

Background

While an increase in bone marrow adiposity is associated with age-related bone disease, the function of bone marrow adipocytes has not been studied. The aim of this study was to characterize and compare the age-related gene expression profiles in bone marrow adipocytes and epididymal adipocytes.

Results

A total of 3918 (13.7%) genes were differentially expressed in bone marrow adipocytes compared to epididymal adipocytes. Bone marrow adipocytes revealed a distinct gene profile with low expression of adipocyte-specific genes peroxisome proliferator-activated receptor gamma (PPARγ), fatty acid binding protein 4 (FABP4), perilipin (Plin1), adipsin (CFD) and high expression of genes associated with early adipocyte differentiation (CCAAT/enhancer binding protein beta (C/EBPβ), regulator of G-protein signaling 2 (RGS2). In addition, a number of genes including secreted frizzled related protein 4 (SFRP4), tumor necrosis factor α (TNFα), transforming growth factor beta 1(TGFβ1), G-protein coupled receptor 109A (GPR109A) and interleukin 6 (IL-6), that could affect adipose-derived signaling to bone are markedly increased in bone marrow adipocytes. Age had a substantial effect on genes associated with mitochondria function and inflammation in bone marrow adipocytes. Twenty seven genes were significantly changed with age in both adipocyte depots. Among these genes, IL6 and GPR109A were significantly reduced with age in both adipocyte depots.

Conclusions

Overall, gene profiling reveals a unique phenotype for primary bone marrow adipocytes characterized by low adipose-specific gene expression and high expression of inflammatory response genes. Bone marrow and epididymal adipocytes share a common pathway in response to aging in mice, but age has a greater impact on global gene expression in epididymal than in bone marrow adipocytes. Genes that are differentially expressed at greater levels in the bone marrow are highly regulated with age.
A library of protein surface patches discriminates between native structures and decoys generated by structure prediction servers
Authors: Gamliel Roi , Kedem Klara , Kolodny Rachel , Keasar Chen
Published: May 2011

Background

Protein surfaces serve as an interface with the molecular environment and are thus tightly bound to protein function. On the surface, geometric and chemical complementarity to other molecules provides interaction specificity for ligand binding, docking of bio-macromolecules, and enzymatic catalysis.

As of today, there is no accepted general scheme to represent protein surfaces. Furthermore, most of the research on protein surface focuses on regions of specific interest such as interaction, ligand binding, and docking sites. We present a first step toward a general purpose representation of protein surfaces: a novel surface patch library that represents most surface patches (~98%) in a data set regardless of their functional roles.

Results

Surface patches, in this work, are small fractions of the protein surface. Using a measure of inter-patch distance, we clustered patches extracted from a data set of high quality, non-redundant, proteins. The surface patch library is the collection of all the cluster centroids; thus, each of the data set patches is close to one of the elements in the library.

We demonstrate the biological significance of our method through the ability of the library to capture surface characteristics of native protein structures as opposed to those of decoy sets generated by state-of-the-art protein structure prediction methods. The patches of the decoys are significantly less compatible with the library than their corresponding native structures, allowing us to reliably distinguish native models from models generated by servers. This trend, however, does not extend to the decoys themselves, as their similarity to the native structures does not correlate with compatibility with the library.

Conclusions

We expect that this high-quality, generic surface patch library will add a new perspective to the description of protein structures and improve our ability to predict them. In particular, we expect that it will help improve the prediction of surface features that are apparently neglected by current techniques.

The surface patch libraries are publicly available at http://www.cs.bgu.ac.il/~keasar/patchLibrary.
Characterization of a cryptic plasmid pSM429 and its application for heterologous expression in psychrophilic Pseudoalteromonas
Authors: Zhao Dian-Li , Yu Zi-Chao , Li Ping-Yi , Wu Zhao-Yu , Chen Xiu-Lan , Shi Mei , Yu Yong , Chen Bo , Zhou Bai-Cheng , Zhang Yu-Zhong
Published: May 2011

Background

Pseudoalteromonas is an important genus widespread in marine environment, and a lot of psychrophilic Pseudoalteromonas strains thrive in deep sea and polar sea. By now, there are only a few genetic systems for Pseudoalteromonas reported and no commercial Pseudoalteromonas genetic system is available, which impedes the study of Pseudoalteromonas, especially for psychrophilic strains. The aim of this study is to develop a heterologous expression system for psychrophilic Pseudoalteromonas.

Results

A cryptic plasmid pSM429 isolated from psychrophilic Pseudoalteromonas sp. BSi20429 from the Arctic sea ice, was sequenced and characterized. The plasmid pSM429 is 3874 bp in length, with a G+C content of 28%. Four putative open reading frames (ORFs) were identified on pSM429. Based on homology, the ORF4 was predicted to encode a replication initiation (Rep) protein. A shuttle vector (Escherichia coli, Pseudoalteromonas), pWD, was constructed by ligating pSM429 and pUC19 and inserting a chloramphenicol acetyl transferase (CAT) cassette conferring chloramphenicol resistance. To determine the minimal replicon of pSM429 and to check the functionality of identified ORFs, various pWD derivatives were constructed. All derivatives except the two smallest ones were shown to allow replication in Pseudoalteromonas sp. SM20429, a plasmid-cured strain of Pseudoalteromonas sp. BSi20429, suggesting that the orf4 and its flanking intergenic regions are essential for plasmid replication. Although not essential, the sequence including some repeats between orf1 and orf2 plays important roles in segregational stability of the plasmid. With the aid of pWD-derived plasmid pWD2, the erythromycin resistance gene and the cd gene encoding the catalytic domain of a cold-adapted cellulase were successfully expressed in Pseudoalteromonas sp. SM20429.

Conclusions

Plasmid pSM429 was isolated and characterized, and the regions essential for plasmid replication and stability were determined, helping the development of pSM429-based shuttle vectors. The shuttle vectors pWD and its derivatives could be used as cloning vectors for Pseudoalteromonas, offering new perspectives in the genetic manipulation of Pseudoalteromonas strains. With the aid of pWD-derived vector and its host, the erythromycin resistance gene and the cd gene of a cold-adapted protein were successfully expressed, indicating that the potential use of this system for recombinant protein production, especially for cold-adapted proteins.
Low-temperature fabrication of layered self-organized Ge clusters by RF-sputtering
Authors: Pinto Sara RC , Rolo Anabela G , Buljan Maja , Chahboun Adil , Bernstorff Sigrid , Barradas Nuno P , Alves Eduardo , Kashtiban Reza J , Bangert Ursel , Gomes Maria JM
Published: May 2011

In this article, we present an investigation of (Ge + SiO2)/SiO2 multilayers deposited by magnetron sputtering and subsequently annealed at different temperatures. The structural properties were investigated by transmission electron microscopy, grazing incidence small angles X-ray scattering, Rutherford backscattering spectrometry, Raman, and X-ray photoelectron spectroscopies. We show a formation of self-assembled Ge clusters during the deposition at 250°C. The clusters are ordered in a three-dimensional lattice, and they have very small sizes (about 3 nm) and narrow size distribution. The crystallization of the clusters was achieved at annealing temperature of 700°C.
Complement C3 serum levels in anorexia nervosa: a potential biomarker for the severity of disease?
Authors: Flierl Michael A , Gaudiani Jennifer L , Sabel Allison L , Long Carlin S , Stahel Philip F , Mehler Philip S
Published: May 2011

Background

Anorexia nervosa carries the highest mortality rate of any psychiatric disorder. Even the most critically ill anorexic patients may present with normal 'standard' laboratory values, underscoring the need for a new sensitive biomarker. The complement cascade, a major component of innate immunity, represents a driving force in the pathophysiology of multiple inflammatory disorders. The role of complement in anorexia nervosa remains poorly understood. The present study was designed to evaluate the role of complement C3 levels, the extent of complement activation and of complement hemolytic activity in serum, as potential new biomarkers for the severity of anorexia nervosa.

Patients and methods

This was a prospective cohort study on 14 patients with severe anorexia nervosa, as defined by a body mass index (BMI) <14 kg/m2. Serum samples were obtained in a biweekly manner until hospital discharge. A total of 17 healthy subjects with normal BMI values served as controls. The serum levels of complement C3, C3a, C5a, sC5b-9, and of the 50% hemolytic complement activity (CH50) were quantified and correlated with the BMIs of patients and control subjects.

Results

Serum C3 levels were significantly lower in patients with anorexia nervosa than in controls (median 3.7 (interquartile range (IQR) 2.5-4.9) vs 11.4 (IQR 8.9-13.7,P<0.001). In contrast, complement activation fragments and CH50 levels were not significantly different between the two groups. There was a strong correlation between index C3 levels and BMI (Spearman correlation coefficient = 0.71,P<0.001).

Conclusions

Complement C3 serum levels may represent a sensitive new biomarker for monitoring the severity of disease in anorexia nervosa. The finding from this preliminary pilot study will require further investigation in future prospective large-scale multicenter trials.
Lack of neuroprotection in the absence of P2X7 receptors in toxin-induced animal models of Parkinson's disease
Authors: Hracskó Zsuzsanna , Baranyi Mária , Csölle Cecilia , Gölöncsér Flóra , Madarász Emilia , Kittel Ágnes , Sperlágh Beáta
Published: May 2011

Background

Previous studies indicate a role of P2X7 receptors in processes that lead to neuronal death. The main objective of our study was to examine whether genetic deletion or pharmacological blockade of P2X7 receptors influenced dopaminergic cell death in various models of Parkinson's disease (PD).

Results

mRNA encoding P2X7 and P2X4 receptors was up-regulated after treatment of PC12 cells with 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP). P2X7 antagonists protected against MPTP and rotenone induced toxicity in the LDH assay, but failed to protect after rotenone treatment in the MTT assay in PC12 cells and in primary midbrain culture. In vivo MPTP and in vitro rotenone pretreatments increased the mRNA expression of P2X7 receptors in the striatum and substantia nigra of wild-type mice. Basal mRNA expression of P2X4 receptors was higher in P2X7 knockout mice and was further up-regulated by MPTP treatment. Genetic deletion or pharmacological inhibition of P2X7 receptors did not change survival rate or depletion of striatal endogenous dopamine (DA) content after in vivo MPTP or in vitro rotenone treatment. However, depletion of norepinephrine was significant after MPTP treatment only in P2X7 knockout mice. The basal ATP content was higher in the substantia nigra of wild-type mice, but the ADP level was lower. Rotenone treatment elicited a similar reduction in ATP content in the substantia nigra of both genotypes, whereas reduction of ATP was more pronounced after rotenone treatment in striatal slices of P2X7 deficient mice. Although the endogenous amino acid content remained unchanged, the level of the endocannabinoid, 2-AG, was elevated by rotenone in the striatum of wild-type mice, an effect that was absent in mice deficient in P2X7 receptors.

Conclusions

We conclude that P2X7 receptor deficiency or inhibition does not support the survival of dopaminergic neurons in an in vivo or in vitro models of PD.
A revised nomenclature for transcribed human endogenous retroviral loci
Authors: Mayer Jens , Blomberg Jonas , Seal Ruth L
Published: May 2011

Background

Endogenous retroviruses (ERVs) and ERV-like sequences comprise 8% of the human genome. A hitherto unknown proportion of ERV loci are transcribed and thus contribute to the human transcriptome. A small proportion of these loci encode functional proteins. As the role of ERVs in normal and diseased biological processes is not yet established, transcribed ERV loci are of particular interest. As more transcribed ERV loci are likely to be identified in the near future, the development of a systematic nomenclature is important to ensure that all information on each locus can be easily retrieved.

Results

Here we present a revised nomenclature of transcribed human endogenous retroviral loci that sorts loci into groups based on Repbase classifications. Each symbol is of the format ERV + group symbol + unique number. Group symbols are based on a mixture of Repbase designations and well-supported symbols used in the literature. The presented guidelines will allow newly identified loci to be easily incorporated into the scheme.

Conclusions

The naming system will be employed by the HUGO Gene Nomenclature Committee for naming transcribed human ERV loci. We hope that the system will contribute to clarifying a certain aspect of a sometimes confusing nomenclature for human endogenous retroviruses. The presented system may also be employed for naming transcribed loci of human non-ERV repeat loci.
Primary appendiceal mucinous adenocarcinoma in two first-degree relatives: case report and review
Authors: Racek Adrianne R , Rabe Kari G , Wick Myra J , Psychogios Apostolos , Lindor Noralane M
Published: May 2011

Carcinomas of the appendix are exceedingly rare tumors and have an annual age-adjusted incidence of around 0.4 cases per 100,000. Appendiceal adenocarcinoma accounts for < 0.5% of all gastrointestinal neoplasms and, of these, mucinous adenocarcinomas account for the majority. Published accounts of familial instances of primary appendiceal tumors are strikingly rare. We report two siblings who both developed primary mucinous adenocarcinomas. A genetics evaluation was conducted to determine if there was a recognizable underlying single gene disorder; no DNA mismatch repair defect was evident, and no other diagnosis was apparent. A review of appendiceal cancers seen at Mayo Clinic from l997 to the present was conducted to search for additional familial cases. Among 316 cases of primary appendiceal cancer of any histologic type, this sib pair was the only family reporting a second affected family member. The occurrence of appendiceal cancer in siblings may represent a random occurrence. An exceedingly rare predisposition syndrome cannot be ruled out.
Coupling ground penetrating radar and fluid flow modeling for oilfield monitoring applications
Authors: Miorali Mattia , Zhou Feng , Slob Evert , Arts Rob
Published: May 2011

The recent introduction of smart well technology allows for new geophysical monitoring opportunities. Smart wells, which allow zonal production control, combined with monitoring techniques capable of capturing the arrival of undesired fluids, have the potential to significantly increase the oil recovery. We consider borehole radar as a valuable technology for monitoring of the near-well region. By coupling a drainage process of a bottom water-drive reservoir with electromagnetic simulations, we find that radar sensors located in the production well can successfully map the fluid saturation evolution. In low-conductivity reservoirs [Formula: see text], a system performance above 80 dB is necessary to record reflections in the range of 10 m. Higher conductivity values strongly reduce the radar investigation depth. Despite the technical challenges to implement a permanent down-hole radar system, the potential semi-continuous acquisition would make 4D ground-penetrating radar a promising technology in capturing the near-well fluid dynamics. Suitable environments are bottom water-drive reservoirs with thin oil layer and heavy oil reservoirs exploited by steam-assisted gravity drainage processes.
Approach to the Patient with Nontoxic Multinodular Goiter
Authors: Bahn Rebecca S. , Castro M. Regina
Published: May 2011

Thyroid nodules are very common, and although the majority are benign, approximately 5% may harbor malignancy. The evaluation of the patient with solitary thyroid nodule is generally straightforward and will typically include measurement of serum TSH to assess thyroid function and fine-needle aspiration biopsy of the nodule, with or without ultrasound (US) guidance. The approach to the patient with nontoxic multinodular goiter represents a more difficult problem for the clinician. All patients should have serum TSH measured to assess functional thyroid status and US examination to evaluate the number, size, and sonographic features of the nodules and assist in the selection of nodules that may need fine-needle aspiration biopsy. Patients with nodules yielding malignant cytology should be referred for surgery. Given the lack of reliable markers to predict biological behavior of nodules with suspicious (indeterminate) cytology, patients with such nodules are generally advised to have surgery, unless autonomous function of these nodules can be confirmed by scintigraphy. Most of these patients, however, will ultimately prove to have benign follicular tumors. Many patients with benign but large goiters may experience clinical symptoms of pressure, such as dysphagia, choking sensation, or airway obstruction. Such patients will often require surgery for alleviation of symptoms. In the absence of malignancy, asymptomatic patients may be observed. Radioactive iodine, commonly used in many parts of Europe, is safe and effective and may be a reasonable option for many patients. Periodic follow-up with neck palpation and US exam is recommended for all patients.
Changes in Glucose Homeostasis after Roux-en-Y Gastric Bypass Surgery for Obesity at Day Three, Two Months, and One Year after Surgery: Role of Gut Peptides
Authors: Falkén Y. , Hellström P. M. , Holst J. J. , Näslund E.
Published: May 2011

Context:

Endocrine effects of gastric bypass (GBP) surgery for obesity on glucose homeostasis are not fully understood.

Main Objective:

The main objective of the study was to assess the changes in plasma glucose, insulin, glucagon-like peptide-1 (GLP-1), leptin, somatostatin, glucose-dependent insulinotropic peptide, enteroglucagon, and glucagon early after GBP.

Method:

Twelve obese subjects (body mass index 45.3 ± 1.9 kg/m2) were subjected to a liquid meal without lipids before and 3 d, 2 months, and 1 yr after GBP. Plasma concentrations of glucose, insulin, leptin, and gut peptide hormones were assessed before and for 180 min after the meal. Satiety was measured with visual analog scales. The absorption rate of acetaminophen added to the liquid meal was measured. Insulin resistance was measured by the homeostasis model assessment of insulin resistance.

Results:

All subjects lost weight (body mass index 30.3 ± 1.8 kg/m2 at 1 yr). Fasting glucose was significantly lower on d 3 (P < 0.05). There was a progressive decrease in the homeostasis model assessment of insulin resistance after 2 months postoperatively. Postprandially, there was a progressive rise of GLP-1 and enteroglucagon and a transient increase in pancreatic glucagon release over the study period. There was a leftward shift of the time course of plasma glucose and insulin. Somatostatin release was lower on d 3 (P < 0.05) but then unchanged. The absorption rate of acetaminophen was twice as fast after GBP compared with before surgery and did not change over time. Satiety scores increased markedly postoperatively.

Conclusion:

Both enhanced insulin sensitivity and incretin hormones, such as GLP-1, contribute to the early control of glucose homeostasis. Progressively increasing postprandial levels of enteroglucagon (oxyntomodulin) and GLP-1 facilitate weight loss and enhance insulin effectiveness.
Arsenic trioxide inhibits invasion/migration in SGC-7901 cells by activating the reactive oxygen species-dependent cyclooxygenase-2/matrix metalloproteinase-2 pathway
Authors: Liu Yingxia , Zhang Wenya , Zhang Xiaoning , Qi Yongmei , Huang Dejun , Zhang Yingmei
Published: May 2011

Arsenic trioxide (As2O3) has been shown to inhibit invasion/migration in cancer cells. However, the underlying mechanism is poorly understood. To identify the role of As2O3 in regulating invasion/migration activity in human gastric cancer SGC-7901 cells, the effects of As2O3 on cell invasion/migration activity, the expression of cyclooxygenase-2 (Cox-2), prostaglandin E2 (PGE2), thromboxane B2 (TXB2), leukotriene B4 (LTB4), and matrix metalloproteinase-2 (MMP-2) and intracellular reactive oxygen species (ROS) were examined. Furthermore, N-acetyl-l-cysteine (NAC, a radical scavenger) and celecoxib (a Cox-2 inhibitor) were used to explore the molecular mechanism. The results demonstrated that As2O3 (1 and 2 μmol/L) inhibited invasion/migration activity in SGC-7901 cells at 24 h and suppressed the expression of Cox-2, PGE2 and MMP-2 ( P < 0.05), whereas the same treatment had no significant effect on TXB2 and LTB4 expression. In contrast, intracellular ROS were increased ( P < 0.05). Moreover, NAC eliminated the excessive ROS and restored the expression of Cox-2 and MMP-2 and invasion/migration activity in As2O3-treated cells ( P < 0.05). These results suggest that ROS may be a critical factor in regulating the invasion/migration process. Moreover, celecoxib significantly decreased Cox-2, MMP-2 and PGE2 expression and inhibited invasion/migration activity in As2O3-treated cells ( P < 0.05), indicating that As2O3 inhibits invasion/migration by regulating the expression of Cox-2/PGE2/MMP-2. In conclusion, these results suggest that increased ROS play a critical role in inhibiting invasion/migration by suppressing the Cox-2/MMP-2 pathway in As2O3-treated SGC-7901 cells and regulating intracellular ROS levels may be a promising strategy in gastric cancer therapy.