bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring the Commonalities Between Adaptive Resources and Self-Enhancement in Older Adults' Comparative Judgments of Physical Activity
Authors: Bailis Daniel S. , Chipperfield Judith G. , Perry Raymond P. , Newall Nancy E. , Haynes Tara L.
Published: September 2008

Objective: This study examines the extent to which optimism, control beliefs and motivation, and downward social comparison contribute independently to the maintenance of older adults' positive self-evaluations in a functional domain. Method: Adaptive resources/strategies and life satisfaction were measured in personal interviews with 164 community-dwelling older adults. Participants judged their physical activity compared with the average person of their age and wore an accelerometer for 24 hours. Commonality analysis was used to estimate unique versus shared effects of the resource/strategy variables on a residual measure of self-enhancement, obtained by adjusting the comparative judgments for participants' age and objectively measured physical activity. Results: Self-enhancement was positively related to life satisfaction. Perceived control and optimism had shared positive effects on self-enhancement, whereas downward social comparison had a unique positive effect. Discussion: Self-enhancement of physical activity plays a part in at least two adaptive profiles with implications for older adults' well-being and health.
Tissue factor in antiphospholipid antibody-induced pregnancy loss: a pro-inflammatory molecule
Authors: Girardi G , Mackman N
Published: September 2008

Fetal loss in patients with antiphospholipid antibodies (aPL) has been ascribed to thrombosis of placental vessels. However, we have shown that inflammation, specifically complement activation with generation of the anaphylotoxin C5a, is an essential mediator of fetal injury. We have analysed the role of tissue factor (TF) in a mouse model of aPL-induced pregnancy loss. TF is the major cellular activator of the coagulation cascade but also has cell signaling activity. Mice that received aPL-IgG showed strong TF staining throughout the decidua and on embryonic debris. This TF staining was not associated with either fibrin staining or thrombi in deciduas. The absence of fibrin deposition and thrombi suggests that TF-dependent activation of coagulation does not mediate aPL-induced pregnancy loss.We found that either blockade of TF with a monoclonal antibody in wild type mice or a genetic reduction of TF prevented aPL-induced inflammation and pregnancy loss indicated a pathogenic role for TF in aPL-induced pregnancy complications. In response to aPL-generated C5a, neutrophils express TF potentiating inflammation in the deciduas and leading to miscarriages. Importantly, we showed that TF in myeloid cells, but not fetal-derived cells (trophoblasts), was associated with fetal injury, suggesting that the site for pathologic TF expression is neutrophils. We found that TF expression in neutrophils contributes to respiratory burst and subsequent trophoblast injury and pregnancy loss induced by aPL. The identification of TF, acting as an important pro-inflammatory mediator in aPL-induced fetal injury, provides a new target for therapy to prevent pregnancy loss in the aPL syndrome.
Resistance to annexin A5 anticoagulant activity: a thrombogenic mechanism for the antiphospholipid syndrome
Authors: Rand JH , Wu XX , Quinn AS , Taatjes DJ
Published: September 2008

The phospholipid binding protein, annexin A5 (AnxA5), has potent anticoagulant properties that result from its forming 2-dimensional crystals over phospholipids, blocking the availability of the phospholipids for critical coagulation enzyme reactions. This article reviews the evidence that antiphospholipid antibodies can disrupt this anticoagulant shield and unmask thrombogenic anionic phospholipids, which may thereby contribute to thrombosis in patients with the antiphospholipid syndrome (APS). This mechanism for thrombosis in APS can be monitored with coagulation assays for resistance to anticoagulant activity of AnxA5.
An Intuitive Study of Fractional Derivative Modeling and Fractional Quantum in Soft Matter
Authors: Chen Wen
Published: September 2008

Soft matter (such as biomaterials, polymers, sediments, oil, emulsions, etc) has become an important bridge between theoretical physics and a range of applied disciplines. Its fundamental physical mechanism, however, is largely obscure. This study makes a first attempt to connect the fractional Schrodinger equation and soft matter physics within a consistent framework from empirical power scaling to phenomenological kinetics and macromechanics to mesoscopic quantum mechanics. The new perspectives of this study are the fractional quantum relationships in soft matter, which show that Lévy statistics and fractional Brownian motion are essentially related to momentum and energy, respectively. Fractional quantum theory has been conjectured as underlying fractal mesostructures and many-body interactions of macromolecules in soft matter, and is experimentally testable.
Recursive Distributions of Poles and Zeros for Linear Phase Variations
Authors: Sabatier Jocelyn , Moze Mathieu , Lanusse Patrick , Oustaloup Alain
Published: September 2008

This article discusses two recursive distributions of poles and zeros that permit the synthesis of a transmittance whose phase variations are linear in respect to logarithmic variations of the frequency. Slope and magnitude are adjusted through two parameters. One of the resulting transmittances is particularly attractive for the synthesis of a CRONE controller if constraints on closed loop pole locations or on sensitivity function energies are imposed. The resulting transmittance also permits us to obtain a state space description of the open and closed loop systems, which is required if a linear parameter varying system is to be controlled.
Stability of Discrete Fractional Order State-space Systems
Authors: Dzieliński Andrzej , Sierociuk Dominik
Published: September 2008

In this article, the stability problem for discrete-time fractional order systems is considered. The discrete-time fractional order state-space model introduced by the authors in earlier works is recalled in this context. The proposed stability definition is adopted from one used for infinite dimensional systems. Using this definition, the main stability result is presented in the form of a simple stability condition for the fractional order discrete state-space system. This is one of the first few attempts to give the stability conditions for this type of system. The condition presented is conservative1 the method gives only sufficient conditions, and the stability areas obtained when using it are smaller than those obtained from numerical solutions of the system. The relationship between the eigenvalues of the system matrix and the poles of the fractional-order system transfer function is also discussed. The main observation in this respect is that a set of L poles is related to every eigenvalue of the system matrix.
New Results on the Controllability and Observability of Fractional Dynamical Systems
Authors: Bettayeb Maamar , Djennoune Said
Published: September 2008

In this article, we describe some new results on the controllability and observability of linear dynamical systems involving a fractional derivative of order α. We show that the input control energy required to drive the state in a given direction and the energy available at the output are related to the observability and the controllability Gramians, respectively. Our results can be considered as a generalization of the known corresponding results for the integer order case to the fractional order one, since for α 1 1, the results for the integer case are recovered.
Variable-fractional-order Dead-beat Control of an Electromagnetic Servo
Authors: Ostalczyk Piotr , Rybicki Tomasz
Published: September 2008

In this article, a simple dead-beat control for an electromagnetic servo is proposed. An electromagnetic servo is identified as a third-order linear continuous-time plant. A method of a dead-beat control of its discrete equivalence is proposed. A variable-order, fractional-order backward difference is used in the control algorithm.
Modeling the Cardiac Tissue Electrode Interface Using Fractional Calculus
Authors: Magin R.L. , Ovadia M.
Published: September 2008

The tissue electrode interface is common to all forms of biopotential recording (e.g., ECG, EMG, EEG) and functional electrical stimulation (e.g., pacemaker, cochlear implant, deep brain stimulation). Conventional lumped element circuit models of electrodes can be extended by generalization of the order of differentiation through modification of the defining current-voltage relationships. Such fractional order models provide an improved description of observed bioelectrode behaviour, but recent experimental studies of cardiac tissue suggest that additional mathematical tools may be needed to describe this complex system.
Vibration Modes of an Axially Moving Double Belt System with Creep Layer
Authors: Hedrih Katica (Stevanović)
Published: September 2008

Starting from existing literature on free transversal vibrations of single axially moving strings, this article provides derivations of, and analytical solutions for, coupled partial fractional order differential equations for the transversal vibrations of an axially moving sandwich double belt system with creep layer. Some of the vibration modes of such a system are also determined.
A Formulation and Numerical Scheme for Fractional Optimal Control Problems
Authors: Agrawal Om P.
Published: September 2008

This article presents a general formulation and general numerical scheme for a class of fractional optimal control problems (FOCPs). The fractional derivative is described in the Caputo sense. The performance index of a FOCP is considered as a function of both the state and the control variables, and the dynamic constraints are expressed by a set of fractional differential equations. The calculus of variations, the Lagrange multiplier, and the formula for fractional integration by parts are used to obtain Euler-Lagrange equations for the FOCP. The formulation presented, and the resulting equations, are very similar to those that appear in classical optimal control theory. Thus, the present formulation essentially extends classical control theory to fractional dynamic systems. The formulation is used to derive the control equations for a quadratic linear fractional control problem. An iterative numerical scheme for finding the approximate numerical solution of the resulting equations is presented. For a linear system, this method results in a set of linear simultaneous equations, which can be solved directly. Numerical results for a FOCP are presented to demonstrate the feasibility of the method. It is shown that the solutions converge as the number of grid points increases, and the solutions approach the classical solutions as the order of the fractional derivatives approaches 1. The formulation presented is simple, and can be extended to other FOCPs.
Design of Optimum Systems of Viscoelastic Vibration Absorbers for a Given Material Based on the Fractional Calculus Model
Authors: De Espíndola José João , Bavastri Carlos Alberto , De Oliveira Lopes Eduardo Márcio
Published: September 2008

So-called vibration absorbers, which might more appropriately be called vibration neutralizers, are mechanical devices designed to be attached to another mechanical system, or structure, called the primary system, for the purpose of controlling, or reducing, the vibration (and consequent sound production) of machines, structural surfaces and panels. The cheapest and easiest way to construct a vibration absorber is by incorporating a viscoelastic material, functioning as both the resilient and the energy dissipating component. The viscoelastic material acts as a damped spring. This article sets out to describe how to design an optimal system of viscoelastic absorbers for a known material, through a model using four fractional parameters. A real example, of the design of a system of six viscoelastic vibration absorbers for mitigation of the response to fluid-structure instability in a hydroelectric generator system, is presented and discussed.
Comparative Analysis of Traditional, Modern, and Renovated Streets in Physical, Visual, and Life Aspects; A Case Study on Buca District — Izmir (Turkey)
Authors: Kilicaslan Cigdem , Malkoc Emine , Turel Hatice Sonmez
Published: September 2008

Located within the borders of a conservation development plan, a traditional street structure, a renovated street structure which holds traditionalism and modernism together and a modern street structure constructed within the present settlement have been studied comparatively to determine the degree to which the existing urban structure meets the expectations of today's people.

After an initial search of the literature, including development plans for the study area, the concept of `the street' was examined in detail and the place of streets as the lowest spatial unit in social life evaluated. During the data collection phase expert and student groups, including landscape architects, investigated the area by public survey and direct observation to produce information for consideration by the researchers and an expert panel.

Physical structure and life-style analyses were carried out through on the spot observation together with a public survey using face-to-face interviews and a computer-based visual analysis. During the last phase of the study, all the data obtained were evaluated by the research group and recommendations to direct future activity in planning, designing and primary conservation were developed on the basis of the selected street samples.
Analysis and Design of a New Roof Monitor for Day and Night Illumination of a Large Volume Room
Authors: Snyder Mark E. , Megri Ahmed C. , Haghighat Fariborz
Published: September 2008

The Illuminating Engineering Society of North America (IESNA) Lighting Handbook recommends illuminance criteria for specific applications to raise the ``minimum standard of care'' required of lighting design to meet human, economic environmental, and architectural concerns. Specific criteria for daylighting of auditoriums (i.e., large rooms) focus on the importance of daylighting integration, control and flexibility, illuminance levels, light distribution, color appearance, and glare. A new skylight design for day and night illumination of a large volume room is proposed. The feasibility of this unique design uses clerestory windows, also known as a roof monitor, and an outdoor lighting array. The design illuminates a room 100-feet wide, 100-feet long, and 75-feet high, located at 40°-north latitude. Comparisons have been made to flat skylight wells for the same volume. The demonstrated design meets lighting criteria that satisfy IESNA standards for day and night to play basketball, a task that requires low contrast and involves small sized objects, like a basketball. The design has been tested with AGI32 software created by Lighting Analysts, Inc of Littleton, Colorado. Results show the new skylight meets IESNA criteria F (for tasks like basketball) during the daytime with an assist by external lighting as the setting sun reduces the daylight.
Working with Diverse Communities in East Calgary, Alberta
Authors: Lam Both Peter , Neff Ron
Published: September 2008

• Summary: This article draws on the findings of diversity audit study done at the East Area Office of the City of Calgary, in Canada. It identifies existing strengths and gaps in addressing diversity and social inclusion within the office staff and in the program planning, design and delivery to the diverse communities in the east of Calgary.

• Findings: Although staff of the area office feel a strong sense of belong in the workplace and work collaboratively with each other in different streams, it was identified that more collaboration needs to be established between the community social workers and community recreation coordinators. It was also found that almost all staff in the area office have no knowledge for procedures to report discrimination in the work place. On the other hand, the community consultations have identified that East Area Office needs to develop close relationship with gay, lesbian, bisexual and transgendered communities, which at the time of the study were not specifically targeted with programs by the office.

• Application: Building from the disconnect between program planning, design and delivery on the one hand, and the inclusion of all the diverse communities on the other hand, the authors present opportunities for dialogue and partnership development to enhance collaborative work between the communities and the East Area Office. Through this collaboration, programs will be planned, designed and delivered with appropriate cultural sensitivity. As well, the authors emphasize the need to strengthen collaborative work between the community social workers (CSWs) and the community recreation coordinators (CRCs), which are the two staff streams working in East Area Office so that their efforts can complement each other.
A comprehensive comparison of the continual reassessment method to the standard 3 + 3 dose escalation scheme in Phase I dose-finding studies
Authors: Iasonos Alexia , Wilton Andrew S , Riedel Elyn R , Seshan Venkatraman E , Spriggs David R
Published: September 2008

Background An extensive literature has covered the statistical properties of the Continual Reassessment Method (CRM) and the modifications of this method. While there are some applications of CRM designs in recent Phase I trials, the standard method (SM) of escalating doses after three patients with an option for an additional three patients SM remains very popular, mainly due to its simplicity. From a practical perspective, clinicians are interested in designs that can estimate the MTD using fewer patients for a fixed number of doses, or can test more dose levels for a given sample size.

Purpose This article compares CRM-based methods with the SM in terms of the number of patients needed to reach the MTD, total sample size required, and trial duration.

Methods The comparisons are performed under two alternative schemes: a fixed or a varying sample approach with the implementation of a stopping rule. The stopping rule halts the trial if the confidence interval around the MTD is within a pre-specified bound. Our simulations evaluated several CRM-based methods under different scenarios by varying the number of dose levels from five to eight and the location of the true MTD.

Results CRM and SM are comparable in terms of how fast they reach the MTD and the total sample size required when testing a limited number of dose levels (≤5), but as the number of dose levels increases, CRM reaches the MTD in fewer patients when used with a fixed sample of 20 patients. However, a sample size of 20—25 patients is not sufficient to achieve a narrow precision around the estimated toxicity rate at the MTD.

Limitations We focused on methods with practical design features that are of interest to clinicians. However, there are several alternative CRM-based designs that are not investigated in this manuscript, and hence our results are not generalizable to other designs.

Conclusions We show that CRM-based methods are an improvement over the SM in terms of accuracy and optimal dose allocation in almost all cases, except when the true dose is among the lower levels. Clinical Trials 2008; 5: 465—477. http://ctj.sagepub.com
Sample size calculations for 3-level cluster randomized trials
Authors: Teerenstra Steven , Moerbeek Mirjam , van Achterberg Theo , Pelzer Ben J , Borm George F
Published: September 2008

Background The first applications of cluster randomized trials with three instead of two levels are beginning to appear in health research, for instance, in trials where different strategies to implement best-practice guidelines are compared. In such trials, the strategy is implemented in health care units (`clusters') and aims at changing the behavior of health care professionals working in this unit (`subjects'), while the effects are measured at patient level (`evaluations').

Purpose To guide the choice of number of clusters, number of subjects per cluster, and number of evaluations per subject.

Methods We derive a sample size formula and investigate the influence of sample allocation on power or number of clusters required.

Results The required sample size is the product of the sample size in absence of correlation and two variance inflation factors (VIFs) that describe the clustering of evaluations within subjects and of subjects within cluster, respectively. Because each VIF is expressed in terms of an interpretable Pearson correlation, subject matter knowledge can be incorporated. Moreover, these Pearson's correlations are related to intracluster correlations (ICCs) from comparable, but 2-level cluster randomized trials. Formulas are obtained to guide the sample allocation (number of clusters, subjects, and evaluations) for minimizing total sample size, minimizing the number of clusters, or maximizing power given a budget constraint.

Limitations Empirical estimates of variance components or ICCs from 3-level cluster trials are scarce which limits reliably powering.

Conclusions When parameterized in terms of Pearson correlations, the two variance inflation factors give quantitative insight into the impact of the number of clusters, subjects and evaluations on power. Moreover, subject matter knowledge as well as ICCs from 2-level cluster randomized trials can be incorporated in the sample size calculation, when empirical estimates of variance components or ICCs from a pilot or comparable 3-level study are lacking. Clinical Trials 2008; 5: 486—495. http://ctj.sagepub.com
Biopolymer–clay nanocomposites for controlled drug delivery
Authors: Viseras C. , Aguzzi C. , Cerezo P. , Bedmar M. C.
Published: September 2008

Polymer–clay nanocomposites have attracted great attention worldwide from both academic and industrial points of view. This review aims at reporting on very recent developments in types of polymer–clay nanocomposites, their constituents, synthetic routes, properties and their uses as carriers for drug delivery. This new family of composite materials frequently exhibits remarkable improvements of material properties when compared with the matrix polymers alone or conventional micro- and macrocomposites. Pharmaceutically, interesting improvements include increased mechanical and rheological properties, reduced drug permeability and water uptake and controlled release characteristics. On the basis of these properties, polymer–clay nanocomposites are extending their applicability to the design of new drug release dosage forms with highly specific technological and biopharmaceutical properties, such as swelling, film forming, bioadhesion, and cell uptake. Overall, there is an essential requirement directed towards a more comprehensive understanding of the supramolecular structure, drug loading and release mechanisms of these hybrid materials.
Degradable polyethylenimines as gene carriers
Authors: Jiang H.-L. , Arote R. , Jere D. , Kim Y.-K. , Cho M.-H. , Cho C.-S.
Published: September 2008

Gene therapy is a powerful treatment for inborn and acquired diseases. The development of safe and effective gene delivery systems is a great challenge to make the human gene therapy a reality. Viral vectors have been commonly employed due to the high transfection efficiency, however, their application to the human body is often frustrated by immunogenicity, potential infectivity, complicated production, and inflammation. Non-viral vectors have been widely proposed as safer alternatives to viral vectors by reason of unique advantages such as less immune reaction against repeated administration, ease of synthesis, cell/tissue targeting, unrestricted plasmid size, and low cost. Among non-viral systems, cationic polymers have gained increasing attention because they can easily form self-assembly with DNA. Polyethylenimine (PEI) is one of the most popular cationic polymers investigated in non-viral gene therapy due to its ability to generate elevated levels of gene expression in vitro and in vivo compared to another non-viral carriers. However, the PEI showed high cytotoxicity, which depends on the molecular weight of the PEI. Recently, the degradable PEIs were synthesised to have high transfection efficiency with low cytotoxicity. The present review describes recent progress on the development of degradable PEIs as non-viral vectors. The present paper also summarises structure of degradable PEIs–transfection relationship to provide a novel insight with respect to this type of gene delivery system. First, linear degradable polymers based on linear PEIs are represented. Second, branched polymers based on branched PEIs are discussed. Third, grafted degradable copolymers based on branched PEIs are explained.
Nanodiagnostics performed on human red blood cells with atomic force microscopy
Authors: Hekele O. , Goesselsberger C. G. , Gebeshuber I. C.
Published: September 2008

Atomic force microscopy can yield valuable information concerning basic physical properties as well as alterations of human red blood cells. Erythropoietin is a hormone that is naturally produced in the kidney to stimulate the growth of red blood cells. Administration of genetically engineered synthetic erythropoietin stimulates the production of additional red blood cells. Therefore erythropoietin is used for blood doping in serious sports. The present study aims at investigating any differences in structure and stiffness of red blood cells which are produced body own or with synthetic erythropoietin. The samples are prepared via standard methods, and atomic force spectroscopy with trigger forces of three micronewtons is performed in ambient air. The penetration depth does not reveal statistically relevant differences in the two types of red blood cells. Furthermore, cells with a penetration depth four times as large as healthy ones are encountered in the samples of one donor. Subsequent medical examination revealed a rare type of diabetes. Atomic force spectroscopy shall serve as fast screening method for nanodiagnostics of diseases that alter surface nanomechanical properties.
Definition, assessment and treatment of wheezing disorders in preschool children: an evidence-based approach
Authors: Brand P. L. P. , Baraldi E. , Bisgaard H. , Boner A. L. , Castro-Rodriguez J. A. , Custovic A. , de Blic J. , de Jongste J. C. , Eber E. , Everard M. L. , Frey U. , Gappa M. , Garcia-Marcos L. , Grigg J. , Lenney W. , Le Souëf P. , McKenzie S. , Merkus P. J. F. M. , Midulla F. , Paton J. Y. , Piacentini G. , Pohunek P. , Rossi G. A. , Seddon P. , Silverman M. , Sly P. D. , Stick S. , Valiulis A. , van Aalderen W. M. C. , Wildhaber J. H. , Wennergren G. , Wilson N. , Zivkovic Z. , Bush A.
Published: September 2008

There is poor agreement on definitions of different phenotypes of preschool wheezing disorders. The present Task Force proposes to use the terms episodic (viral) wheeze to describe children who wheeze intermittently and are well between episodes, and multiple-trigger wheeze for children who wheeze both during and outside discrete episodes. Investigations are only needed when in doubt about the diagnosis.

Based on the limited evidence available, inhaled short-acting β2-agonists by metered-dose inhaler/spacer combination are recommended for symptomatic relief. Educating parents regarding causative factors and treatment is useful. Exposure to tobacco smoke should be avoided; allergen avoidance may be considered when sensitisation has been established. Maintenance treatment with inhaled corticosteroids is recommended for multiple-trigger wheeze; benefits are often small. Montelukast is recommended for the treatment of episodic (viral) wheeze and can be started when symptoms of a viral cold develop.

Given the large overlap in phenotypes, and the fact that patients can move from one phenotype to another, inhaled corticosteroids and montelukast may be considered on a trial basis in almost any preschool child with recurrent wheeze, but should be discontinued if there is no clear clinical benefit.

Large well-designed randomised controlled trials with clear descriptions of patients are needed to improve the present recommendations on the treatment of these common syndromes.
Occupational asthma caused byArabidopsis thaliana: a case of laboratory plant allergy
Authors: Yates B. , De Soyza A. , Harkawat R. , Stenton C.
Published: September 2008

A 36-yr-old male never-smoker with an 8-yr history of hay fever but no past history of asthma undertook a 3-yr research project involving the plantArabidopsis thaliana.

The subject was based in a small laboratory with an attached growing room. After 30 months of research, he began to develop breathlessness within 5–10 min of entering the laboratory.

Initial investigations confirmed asthma with airflow obstruction (forced expiratory volume in one second (FEV1)/forced vital capacity was 3.01/4.75 L; predicted values were 3.67/4.43 L) and increased airway responsiveness. Serial peak expiratory flow measurements showed a work-related pattern. A supervised workplace challenge test led to a fall in FEV1from the baseline value of 3.10 L to 1.95 L within 20 min of entering the growing room. Skin-prick solutions were prepared from Arabidopsis leaves and flower heads; positive 4-mm responses were obtained to the flower heads (i.e.to the pollen).

Arabidopsis is a member of the Brassicaceae family. It is used extensively in plant biology research as its genome is small, has been fully sequenced and is easily manipulated. The present article represents the first reported case of occupational asthma due toArabidopsis thaliana.
Combining classifiers for improved classification of proteins from sequence or structure
Authors: Melvin Iain , Weston Jason , Leslie Christina S , Noble William S
Published: September 2008

Background

Predicting a protein's structural or functional class from its amino acid sequence or structure is a fundamental problem in computational biology. Recently, there has been considerable interest in using discriminative learning algorithms, in particular support vector machines (SVMs), for classification of proteins. However, because sufficiently many positive examples are required to train such classifiers, all SVM-based methods are hampered by limited coverage.

Results

In this study, we develop a hybrid machine learning approach for classifying proteins, and we apply the method to the problem of assigning proteins to structural categories based on their sequences or their 3D structures. The method combines a full-coverage but lower accuracy nearest neighbor method with higher accuracy but reduced coverage multiclass SVMs to produce a full coverage classifier with overall improved accuracy. The hybrid approach is based on the simple idea of "punting" from one method to another using a learned threshold.

Conclusion

In cross-validated experiments on the SCOP hierarchy, the hybrid methods consistently outperform the individual component methods at all levels of coverage.

Code and data sets are available athttp://noble.gs.washington.edu/proj/sabretooth
Quality assessment parameters for EST-derived SNPs from catfish
Authors: Wang Shaolin , Sha Zhenxia , Sonstegard Tad S , Liu Hong , Xu Peng , Somridhivej Benjaporn , Peatman Eric , Kucuktas Huseyin , Liu Zhanjiang
Published: September 2008

Background

SNPs are abundant, codominantly inherited, and sequence-tagged markers. They are highly adaptable to large-scale automated genotyping, and therefore, are most suitable for association studies and applicable to comparative genome analysis. However, discovery of SNPs requires genome sequencing efforts through whole genome sequencing or deep sequencing of reduced representation libraries. Such genome resources are not yet available for many species including catfish. A large resource of ESTs is to become available in catfish allowing identification of large number of SNPs, but reliability of EST-derived SNPs are relatively low because of sequencing errors. This project was designed to answer some of the questions relevant to quality assessment of EST-derived SNPs.

Results

wo factors were found to be most significant for validation of EST-derived SNPs: the contig size (number of sequences in the contig) and the minor allele sequence frequency. The larger the contigs were, the greater the validation rate although the validation rate was reasonably high when the contigs contain four or more EST sequences with the minor allele sequence being represented at least twice in the contigs. Sequence quality surrounding the SNP under test is also crucially important. PCR extension appeared to be limited to a very short distance, prohibiting successful genotyping when an intron was present, a surprising finding.

Conclusion

Stringent quality assessment measures should be used when working with EST-derived SNPs. In particular, contigs containing four or more ESTs should be used and the minor allele sequence should be represented at least twice. Genotyping primers should be designed from a single exon, completely avoiding introns. Application of such quality assessment measures, along with large resources of ESTs, should provide effective means for SNP identification in species where genome sequence resources are lacking.
The influence of the Cyclin D1 870 G>A polymorphism as an endometrial cancer risk factor
Authors: Ashton Katie A , Proietto Anthony , Otton Geoffrey , Symonds Ian , McEvoy Mark , Attia John , Gilbert Michael , Hamann Ute , Scott Rodney J
Published: September 2008

Background

Cyclin D1 is integral for the G1 to S phase of the cell cycle as it regulates cellular proliferation. A polymorphism in cyclin D1, 870 G>A, causes overexpression and supports uncontrollable cellular growth. This polymorphism has been associated with an increased risk of developing many cancers, including endometrial cancer.

Methods

The 870 G>A polymorphisms (rs605965) in the cyclin D1 gene was genotyped in an Australian endometrial cancer case-control population including 191 cases and 291 controls using real-time PCR analysis. Genotype analysis was performed using chi-squared (χ2) statistics and odds ratios were calculated using unconditional logistic regression, adjusting for potential endometrial cancer risk factors.

Results

Women homozygous for the variant cyclin D1 870 AA genotype showed a trend for an increased risk of developing endometrial cancer compared to those with the wild-type GG genotype, however this result was not statistically significant (OR 1.692 95% CI (0.939–3.049), p = 0.080). Moreover, the 870 G>A polymorphism was significantly associated with family history of colorectal cancer. Endometrial cancer patients with the homozygous variant AA genotype had a higher frequency of family members with colorectal cancer in comparison to endometrial cancer patients with the GG and combination of GG and GA genotypes (GG versus AA; OR 2.951, 95% CI (1.026–8.491), p = 0.045, and GG+GA versus AA; OR 2.265, 95% CI (1.048–4.894), p = 0.038, respectively).

Conclusion

These results suggest that the cyclin D1 870 G>A polymorphism is possibly involved in the development of endometrial cancer. A more complex relationship was observed between this polymorphism and familial colorectal cancer.
The fatty acid binding protein 7 (FABP7) is involved in proliferation and invasion of melanoma cells
Authors: Slipicevic Ana , Jørgensen Kjersti , Skrede Martina , Rosnes Anne Katrine Ree , Trøen Gunhild , Davidson Ben , Flørenes Vivi Ann
Published: September 2008

Background

The molecular mechanisms underlying melanoma tumor development and progression are still not completely understood. One of the new candidates that emerged from a recent gene expression profiling study is fatty acid-binding protein 7 (FABP7), involved in lipid metabolism, gene regulation, cell growth and differentiation.

Methods

We studied the functional role of FABP7 in human melanoma cell lines and using immunohistochemistry analyzed its expression pattern and clinical role in 11 nevi, 149 primary melanomas and 68 metastases.

Results

FABP7 mRNA and protein level is down-regulated following treatment of melanoma cell lines with a PKC activator (PMA) or MEK1 inhibitor (PD98059). Down-regulation of FABP7 using siRNA decreased cell proliferation and invasion but did not affect apoptosis. In clinical specimens, FABP7 was expressed in 91% of nevi, 71% of primary melanomas and 70% of metastases, with a cytoplasmic and/or nuclear localization. FABP7 expression was associated with tumor thickness in superficial spreading melanoma (P = 0.021). In addition, we observed a trend for an association between FABP7 expression and Ki-67 score (P = 0.070) and shorter relapse-free survival (P = 0.069) in this group of patients.

Conclusion

Our data suggest that FABP7 can be regulated by PKC and the MAPK/ERK1/2 pathway through independent mechanisms in melanoma cell lines. Furthermore, FABP7 is involved in cell proliferation and invasion in vitro, and may be associated with tumor progression in melanoma.
Pharmaceutical induction of ApoE secretion by multipotent mesenchymal stromal cells (MSCs)
Authors: Zeitouni Suzanne , Ford Brian S , Harris Sean M , Whitney Mandolin J , Gregory Carl A , Prockop Darwin J
Published: September 2008

Background

Apolipoprotein E (ApoE) is a molecular scavenger in the blood and brain. Aberrant function of the molecule causes formation of protein and lipid deposits or "plaques" that characterize Alzheimer's disease (AD) and atherosclerosis. There are three human isoforms of ApoE designated ε2, ε3, and ε4. Each isoform differentially affects the structure and function of the protein and thus the development of disease. Homozygosity for ApoE ε4 is associated with atherosclerosis and Alzheimer's disease whereas ApoE ε2 and ε3 tend to be protective. Furthermore, the ε2 form may cause forms of hyperlipoproteinemia. Therefore, introduction of ApoE ε3 may be beneficial to patients that are susceptible to or suffering from these diseases. Mesenchymal stem cells or multipotent mesenchymal stromal cells (MSCs) are adult progenitor cells found in numerous tissues. They are easily expanded in culture and engraft into host tissues when administered appropriately. Furthermore, MSCs are immunosuppressive and have been reported to engraft as allogeneic transplants. In our previous study, mouse MSCs (mMSCs) were implanted into the brains of ApoE null mice, resulting in production of small amounts of ApoE in the brain and attenuation of cognitive deficits. Therefore human MSCs (hMSCs) are a promising vector for the administration of ApoE ε3 in humans.

Results

Unlike mMSCs, hMSCs were found not to express ApoE in culture; therefore a molecular screen was performed for compounds that induce expression. PPARγ agonists, neural stem cell conditioned medium, osteo-inductive media, dexamethasone, and adipo-inductive media (AIM) were tested. Of the conditions tested, only AIM or dexamethasone induced sustained secretion of ApoE in MSCs and the duration of secretion was only limited by the length of time MSCs could be sustained in culture. Upon withdrawal of the inductive stimuli, the ApoE secretion persisted for a further 14 days.

Conclusion

The data demonstrated that pre-treatment and perhaps co-administration of MSCs homozygous for ApoE ε3 and dexamethasone may represent a novel therapy for severe instances of AD, atherosclerosis and other ApoE-related diseases.
Development of behaviour change communication strategy for a vaccination-linked malaria control tool in southern Tanzania
Authors: Mushi Adiel K , Schellenberg Joanna , Mrisho Mwifadhi , Manzi Fatuma , Mbuya Conrad , Mponda Haji , Mshinda Hassan , Tanner Marcel , Alonso Pedro , Pool Robert , Schellenberg David
Published: September 2008

Background

Intermittent preventive treatment of malaria in infants (IPTi) using sulphadoxine-pyrimethamine and linked to the expanded programme on immunization (EPI) is a promising strategy for malaria control in young children. As evidence grows on the efficacy of IPTi as public health strategy, information is needed so that this novel control tool can be put into practice promptly, once a policy recommendation is made to implement it. This paper describes the development of a behaviour change communication strategy to support implementation of IPTi by the routine health services in southern Tanzania, in the context of a five-year research programme evaluating the community effectiveness of IPTi.

Methods

Mixed methods including a rapid qualitative assessment and quantitative health facility survey were used to investigate communities' and providers' knowledge and practices relating to malaria, EPI, sulphadoxine-pyrimethamine and existing health posters. Results were applied to develop an appropriate behaviour change communication strategy for IPTi involving personal communication between mothers and health staff, supported by a brand name and two posters.

Results

Malaria in young children was considered to be a nuisance because it causes sleepless nights. Vaccination services were well accepted and their use was considered the mother's responsibility. Babies were generally taken for vaccination despite complaints about fevers and swellings after the injections. Sulphadoxine-pyrimethamine was widely used for malaria treatment and intermittent preventive treatment of malaria in pregnancy, despite widespread rumours of adverse reactions based on hearsay and newspaper reports. Almost all health providers said that they or their spouse were ready to take SP in pregnancy (96%, 223/242). A brand name, key messages and images were developed and pre-tested as behaviour change communication materials. The posters contained public health messages, which explained the intervention itself, how and when children receive it and safety issues. Implementation of IPTi started in January 2005 and evaluation is ongoing.

Conclusion

Behaviour Change Communication (BCC) strategies for health interventions must be both culturally appropriate and technically sound. A mixed methods approach can facilitate an interactive process among relevant actors to develop a BCC strategy.
Acute liver failure due to primary angiosarcoma: A case report and review of literature
Authors: Bhati Chandra S , Bhatt Anand N , Starkey Graham , Hubscher Stefan G , Bramhall Simon R
Published: September 2008

Background

Hepatic angiosarcoma is a primary sarcoma of the liver, accounting for only 2% of all primary hepatic malignancies. Acute liver failure is an extremely rare presentation of a primary liver tumour.

Case presentation

We report a case of a seventy year-old man who presented with a very short period of jaundice leading to fulminant hepatic failure (FHF). On further investigation he was found to have primary angiosarcoma of liver.

Conclusion

The treatment outcomes for hepatic angiosarcoma are poor, we discuss the options available and the need for prompt investigation and establishment of a diagnosis
Efficacy of common laboratory disinfectants and heat on killing trypanosomatid parasites
Authors: Wang Xia , Jobe Momodou , Tyler Kevin M , Steverding Dietmar
Published: September 2008

The disinfectants TriGene, bleach, ethanol and liquid hand soap, and water and temperature were tested for their ability to kill bloodstream forms of Trypanosoma brucei, epimastigotes of Trypanosoma rangeli and promastigotes of Leishmania major. A 5-min exposure to 0.2% TriGene, 0.1% liquid hand soap and 0.05% bleach (0.05% NaOCl) killed all three trypanosomatids. Ethanol and water destroyed the parasites within 5 min at concentrations of 15–17.5% and 80–90%, respectively. All three organisms were also killed when treated for 5 min at 50°C. The results indicate that the disinfectants, water and temperature treatment (i.e. autoclaving) are suitable laboratory hygiene measures against trypanosomatid parasites.
Ultrasound evaluation of the abductor hallucis muscle: Reliability study
Authors: Cameron Alyse FM , Rome Keith , Hing Wayne A
Published: September 2008

Background

The Abductor hallucis muscle (AbdH) plays an integral role during gait and is often affected in pathological foot conditions. The aim of this study was to evaluate the within and between‐session intra‐tester reliability using diagnostic ultrasound of the dorso‐plantar thickness, medio‐lateral width and cross‐sectional area, of the AbdH in asymptomatic adults.

Methods

The AbdH muscles of thirty asymptomatic subjects were imaged and then measured using a Philips HD11 Ultrasound machine. Interclass correlation coefficients (ICC) with 95% confidence intervals (CI) were used to calculate both within and between session intra‐tester reliability.

Results

The within‐session reliability results demonstrated for dorso‐plantar thickness an ICC of 0.97 (95% CI: 0.99–0.99); medio‐lateral width an ICC: of 0.97 (95% CI: 0.92–0.97) and cross‐sectional area an ICC of 0.98 (95% CI: 0.98–0.99). Between‐session reliability results demonstrated for dorso‐plantar thickness an ICC of 0.97 (95% CI: 0.95 to 0.98); medio‐lateral width an ICC of 0.94 (95% CI 0.90 to 0.96) and for cross‐sectional area an ICC of 0.79 (95% CI 0.65 to 0.88).

Conclusion

Diagnostic ultrasound has the potential to be a reliable tool for evaluating the AbdH muscle in asymptomatic subjects. Subsequent studies may be conducted to provide a better understanding of the AbdH function in foot and ankle pathologies.
Decreased levels of the gelsolin plasma isoform in patients with rheumatoid arthritis
Authors: Osborn Teresia M , Verdrengh Margareta , Stossel Thomas P , Tarkowski Andrej , Bokarewa Maria
Published: September 2008

Introduction

Gelsolin is an intracellular actin-binding protein involved in cell shape changes, cell motility, and apoptosis. An extracellular gelsolin isoform, plasma gelsolin circulates in the blood of healthy individuals at a concentration of 200 ± 50 mg/L and has been suggested to be a key component of an extracellular actin-scavenging system during tissue damage. Levels of plasma gelsolin decrease during acute injury and inflammation, and administration of recombinant plasma gelsolin to animals improves outcomes following sepsis or burn injuries. In the present study, we investigated plasma gelsolin in patients with rheumatoid arthritis.

Methods

Circulating and intra-articular levels of plasma gelsolin were measured in 78 patients with rheumatoid arthritis using a functional (pyrene-actin nucleation) assay and compared with 62 age- and gender-matched healthy controls.

Results

Circulating plasma gelsolin levels were significantly lower in patients with rheumatoid arthritis compared with healthy controls (141 ± 32 versus 196 ± 40 mg/L, P = 0.0002). The patients' intra-articular plasma gelsolin levels were significantly lower than in the paired plasma samples (94 ± 24 versus 141 ± 32 mg/L, P = 0.0001). Actin was detected in the synovial fluids of all but four of the patients, and immunoprecipitation experiments identified gelsolin-actin complexes.

Conclusions

The plasma isoform of gelsolin is decreased in the plasma of patients with rheumatoid arthritis compared with healthy controls. The reduced plasma concentrations in combination with the presence of actin and gelsolin-actin complexes in synovial fluids suggest a local consumption of this potentially anti-inflammatory protein in the inflamed joint.