bluuebunny/crossref_metadata_2025 huggingface dataset:
An Update on Irritable Bowel Syndrome
Authors: Ahad Md Abdul , Islam Quazi Tarikul
Published: September 2009

Irritable bowel syndrome (IBS) is the most common disorder diagnosed by gastroenterologists and one of the more common ones encountered in general practice. The illness has a large economic impact on health care use and indirect costs, chiefly through absenteeism. IBS is a bio-psychosocial disorder in which three major mechanisms interact: Psychosocial factors, altered motility, and/or heightened sensory function of the intestine. Treatment of patients is based on positive diagnosis of the symptom complex, limited exclusion of underlying organic disease and institution of a therapeutic trial.   doi: 10.3329/taj.v18i1.3310 TAJ 2005; 18(1): 66-71
Progress on Incorporating the Patient Perspective in Outcome Assessment in Rheumatology and the Emergence of Life Impact Measures at OMERACT 9
Authors: KIRWAN JOHN R. , NEWMAN STANTON , TUGWELL PETER S. , WELLS GEORGE A. , HEWLETT SARAH , IDZERA LEANNE , LASLO BRITTA , MARCH LYN M. , MINNOCK PATRICIA , MONTIE PAM , NICKLIN JO , RADER TAMARA , RICHARDS PAMELA , SANDERSON TESSA C. , SUAREZ-ALMAZOR MARIA , TANJONG-GHOGOMU ELIZABETH , UEFFING ERIN , WELCH VIVIAN
Published: September 2009

The Patient Perspective Workshop included over 100 researchers and 18 patient participants from 8 countries. Following preconference reading and short plenary presentations, breakout groups considered work undertaken on measurement of sleep, assessing interventions to develop the effective consumer, and assessing psychological and educational interventions. The workshop explored the best way to identify other outcome domains (and instruments) that should be measured in observational or interventional studies with broader intentions than simply altering outcomes captured in the traditional “core set” plus fatigue. Four sleep questionnaires showed promise and will be the subject of further study. The Effective Consumer scale (EC-17) was reviewed and the concept Effective Consumer was well received. Participants thought it worthwhile to measure the skills and attributes of an effective consumer and develop an intervention that would include education in all of the scale’s categories. Assessment of educational and psychological interventions requires a wider set of instruments than is currently used; these should relate to the purpose of the intervention. This principle was extended to include wider measures of the impact of disease on life, as indicated in the International Classification of Functioning, Disability and Health. Life impact measure sets covering domains appropriate to different rheumatic conditions and focused on different interventions might be defined by future OMERACT consensus. Measurement instruments within these domains that are valid for use in rheumatic conditions can then be identified and, in the case of psychological and educational interventions, chosen to fit with the purpose of the intervention.
Assessing Quality of Sleep in Patients with Rheumatoid Arthritis
Authors: WELLS GEORGE A. , LI TRACY , KIRWAN JOHN R. , PETERSON JOAN , ALETAHA DANIEL , BOERS MAARTEN , BRESNIHAN BARRY , DOUGADOS MAXIME , IDZERDA LEANNE , NICKLIN JO , SUAREZ-ALMAZOR MARIA , WELCH VIVIAN , TUGWELL PETER S.
Published: September 2009

We sought to identify instruments assessing sleep quality that measure the domains of sleep applicable to rheumatoid arthritis (RA) patients and are feasible to use and have appropriate reliability, validity, and responsiveness properties. A systematic review of sleep instruments was conducted. In particular, domains related to sleep that were assessed in the instruments were identified and evaluated. Feasibility characteristics and psychometric properties of instruments were reviewed. At OMERACT 9, the preparatory work was described at the plenary session of the Patient Perspective Workshop, and the tasks of 3 breakout groups in ranking and scoring the domains and sleep instruments were outlined. Each breakout group considered different aspects of sleep: sleep domains, feasibility, and psychometric properties. The rapporteur for each breakout group reported back to the plenary on the domains and sleep instruments that achieved the highest rank/score. The systematic review identified 45 sleep instruments of interest. Based on these instruments, 14 domains of sleep were identified. The top ranked domains were: Sleep Adequacy (1), Sleep Maintenance (2), Sleep Initiation (3) and Daytime Functioning (4). The top ranked instruments on feasibility were: Athens Insomnia Scale (2.3), Medical Outcome Study (MOS) Sleep (4.0), Insomnia Severity Index (4.9), and Women’s Health Insomnia Rating Scale (5.5). The highest scored instruments on psychometric properties were: Athens Insomnia Scale (13.6), Sleep Assessment Questionnaire (13), Pittsburgh Sleep Diary (12), and MOS Sleep (11). Sleep domains have been reviewed, and several sleep instruments have been identified. These instruments should be considered for use in planned clinical trials of RA patients to assess their applicability.
Responsiveness of the Effective Consumer Scale (EC-17)
Authors: SANTESSO NANCY , RADER TAMARA , WELLS GEORGE A. , O’CONNOR ANNETTE M. , BROOKS PETER M. , DRIEDGER MICHELLE , GALLOIS CINDY , KRISTJANSSON ELIZABETH , LYDDIATT ANNE , O’LEARY GRÁINNE , PRINCE MONICA , STACEY DAWN , WALE JANET , WELCH VIVIAN , WILSON ANDREW J. , TUGWELL PETER S.
Published: September 2009

Objective.

The Effective Consumer Scale (EC-17) comprises 17 items measuring the main skills and behaviors people need to effectively manage their healthcare. We tested the responsiveness of the EC-17.

Methods.

Participants, in 2 waves of a 6-week Arthritis Self-Management Program (ASMP) from Arthritis Ireland, received a questionnaire at the first and last week of the weekly ASMP. The questionnaire included the EC-17 and 10 other measures for arthritis. Deficits, mean change, and standard deviations were calculated at baseline and Week 6. The EC-17 scores were compared to the Arthritis Self-Efficacy (ASE) and Patient Activation Measure (PAM) scales. Results were presented at OMERACT 9.

Results.

There is some overlap between the EC-17 and the ASE and PAM; however, most items of greatest deficit in the EC-17 are not covered by those scales. In 327 participants representing both intervention waves (2006 and 2007), the EC-17 was more efficient than the ASE but less efficient than the PAM for detecting improvements after the ASMP, and was moderately correlated with the PAM.

Conclusion.

The EC-17 appears to measure different skills and attributes than the ASE and PAM. Discussions with participants at OMERACT 9 agreed that it is worthwhile to measure the skills and attributes of an effective consumer, and supported the development of an intervention (such as proposed online decision aids) that would include education in the categories in the EC-17.
Síntesis coloidal de materiales nanoestructurados de Al-ZrAl3: Propiedades mecánicas mediante el ensayo miniatura de punzonado
Authors: Díaz L. A. , López M. E. , Rodríguez C. , Belzunce J. , Torrecillas R.
Published: September 2009

En este trabajo se describe un nuevo método de procesamiento coloidal para obtener materiales nanoestructurados de base aluminio con partículas intermetálicas ZrAl3. A partir de una mezcla controlada en alcohol, de polvos de aluminio con un alcóxido precursor de zirconio (C12H28O4Zr) se obtiene, mediante un tratamiento térmico en un horno convencional con atmósfera controlada o por prensado uniaxial en caliente, un polvo nanoestructurado formado por cristales de aluminio sobre los que cristalizan, de forma homogénea, nanopartículas intermetálicas de ZrAl3. La identificación del intermetálico se efectuó por difracción de rayos X y microscopía electrónica de barrido. El comportamiento mecánico de los materiales nanoestructurados desarrollados se evaluó a partir de ensayos de dureza y mediante el ensayo miniatura de punzonado (EMP). Los resultados muestran que la presencia del intermetálico de zirconio hasta un 1,0 % (en peso) de zirconio aumenta la dureza y rigidez de la matriz de aluminio, al tiempo que incrementa su resistencia mecánica (límite elástico y resistencia a la tracción).
Efecto de los hidruros en el comportamiento mecánico de vainas de zircaloy de combustible nuclear en dirección anular
Authors: Martin-Rengel M. A. , Ruiz-Hervías J. , Gómez F. J. , Caballero L. , Valiente A.
Published: September 2009

En este artículo se ha analizado el efecto de los hidruros en el comportamiento mecánico de las vainas de circonio que se emplean para contener las pastillas de combustible nuclear. Dicho comportamiento se ha evaluado en la dirección anular de las vainas (la más solicitada en servicio), mediante ensayos de tracción en anillo sobre muestras con distintas concentraciones de hidrógeno, y se ha propuesto un modelo de elementos finitos en 3D para simular los ensayos. Los hidruros fueron introducidos en las muestras mediante una técnica de carga catódica de hidrógeno y posterior tratamiento térmico. Los resultados muestran que a las concentraciones ensayadas no existe una degradación significativa de las propiedades mecánicas en la dirección circunferencial, aunque los micromecanismos de rotura cambian con el contenido en hidrógeno de las muestras.
Valoración de datos termoquímicos en la desoxidación del acero
Authors: Gómez P. , Reyes F. , Gutiérrez J. , Plascencia G.
Published: September 2009

El presente artículo propone desarrollar un método para juzgar la certidumbre de la información pertinente al equilibrio de desoxidación de fundidos de hierro. Para lograr este objetivo, se recolectaron y evaluaron datos termoquímicos existentes. Las teorías sobre desoxidación se describen mediante el comportamiento Henriano de soluciones diluidas del agente desoxidante y el hierro fundido en equilibrio con un óxido. En este estudio, solo se consideran reacciones convencionales a 1.873 K, de forma tal que se consideraron las constantes de equilibrio y coeficientes de interacción de primer orden. El criterio empleado para utilizar la expresión más adecuada de la energía libre se basó en evaluar dos puntos críticos: uno, donde se satisface una relación oxígeno/desoxidante dictada por la estequiometría y dos,cuando el contenido de oxígeno alcanza un valor mínimo en presencia de una cantidad predeterminada del desoxidante. Los datos obtenidos se representaron en escalas logarítmicas de forma tal que se pudiese apreciar el efecto de las valencias de los desoxidantes. Con la información así clasificada y bajo las restricciones evaluadas en los puntos críticos uno y dos, las composiciones al equilibrio se relacionan con la electronegatividad del desoxidante.
Engendered Representations: Exploring Sexuality through Symbols and Myths
Authors: Du Plessis Rory , Maree Marinda
Published: September 2009

This article reflects the findings of a project that was conducted by the Institute for Women�s and Gender Studies at the University of Pretoria. In particular, the project sought to dialogue with religious and cultural leaders on the taboos, myths and misconceptions of human sexuality.The article provides an analysis of the symbols and myths of sexuality that were presented by these leaders.These symbols and myths were demystif ed to reveal their alignment to patriarchal gender divisions and inequality.This alignment proves problematic for women, as it views men as possessors of their bodies � insofar as women�s bodies are conceived as the vessels for men�s body fluids and the container of the foetus.
The Knowledge Management in Intensive Environments of Knowledge: the Small Incubated Softwares Companies
Authors: Dalfovo Oscar , Scharf Edson Roberto , Krambeck Greyce
Published: September 2009

This article discusses the understanding and behavior of entrepreneurs incubated for software companies (development of information systems, provide services in information technology - hardware and software, and advise on the implementation of administrative management systems) in relation to knowledge, in the obtaining and facilitating the use of knowledge and availability of media. Initially, it sought a fundamental concept for the study and is based contextualise the issue, making the connection with the knowledge of the views of academic and business. After an analysis was conducted based on applied research to executives on their understanding of the concept of knowledge regarding the way in which it operates (professional and personal), concluding with the importance of knowledge for business growth from the person.
ERP Systems Implementation in Complex Organizations
Authors: Fontana Rafaela Mantovani , Neto Alfredo Iarozinski
Published: September 2009

ERP (Enterprise Resource Planning) systems implementation is a great organizational change, which many times does not reach the desired results. This paper proposes to help understand this implementation, considering that the knowledge of change and evolution processes in organizations may lead to other aspects to be considered, assisting in the identification of the most appropriate actions, restrictions and items that may help sustain the change. It proposes a complex organizational reference model to contribute understanding of the implementation process. Research results show that the concepts proposed in this model – subsystems, emergence, behavior attractors and complexity limits – apply to organizations and contribute to the understanding of the changes triggered by an ERP system implementation. Among other contributions, this work shows the importance of potential generation for change, the relationship among the behavior attractor and competitive advantages gained, and organizational systems maturity considerations.
Microelectromechanical Systems (
MEMS
)
Authors: Meyer Jonas , Bischoff Reinhard , Feltrin Glauco
Published: September 2009

Microelectromechanical system (MEMS) sensors are small, generally low power, highly integrated, and, usually, very cheap. These qualities enable the deployment of structural health monitoring (SHM) systems with a large number of sensors, partly integrated into the structure, at affordable costs. MEMS sensors are often used in wireless sensor networks (WSNs), a monitoring technology that heavily bases its features and performance on low‐power sensors.

This article briefly describes a MEMS‐based wireless sensor network that is designed for long‐term structural health monitoring applications. Since WSN nodes are battery powered, in long‐term monitoring applications the power management of the network significantly influences the overall data handling processes. In WSN, data communication is the most energy‐consuming task, hence, transferring all the acquired raw data through the network would dramatically reduce the lifetime of the system. A significant data reduction, which has to be achieved on the nodes, is a challenging task, since it has to be performed with very limited computing power and memory resources, and in competition with other tasks like data communication, self‐organization, and time synchronization. These aspects are illustrated with tests on a cable stay bridge.
Lamb Wave‐BasedSHMfor Laminated Composite Structures
Authors: Soutis Constantinos
Published: September 2009

This article examines the application of low‐frequency Lamb waves for the detection of delaminations (interlaminar cracking) in thick composite laminates. Surface‐mounted piezoelectric devices are excited with a tone burst of a few cycles generating a stress wave that propagates along the structure. Experiments carried out on composite beam specimens are discussed where wave propagation distances over 2 m are achieved and delaminations as small as 1 cm2are successfully identified. The resonance spectrum method, which is based on the study of spectra obtained by forced mechanical resonance of samples using sine‐sweep excitation, is used for measuring theAoLamb‐mode phase velocity. Finite element (FE) analyses of wave generation and propagation in wide laminated plates are also presented. The feasibility of employing piezoelectric devices for the development of smart structures, where a small and lightweight transducer system design is required, is also demonstrated.
Construction Process Monitoring at the
N
ew
B
erlin
M
ain
S
tation
Authors: Helmerich Rosemarie
Published: September 2009

The construction process of the New Berlin Main Station, the former Lehrter Bahnhof, has been monitored from the beginning. In this station, the main European east‐western railway connection crosses the north–south railway lines. Four east‐western bridges, built in the first construction phase, carry the platforms for international lines and suburban train tracks. The outer two bridges carry the supports of the relatively flat glass roof, too. Since the glass roof is very sensitive to vertical displacements, the authorities required a complex monitoring system. This case study describes long‐term measurements with classical and enhanced innovative sensors to monitor vertical displacements of neighboring glass roof supports. Additionally, traditional strain gauges were embedded parallel to long‐gauge length fiber‐optic strain sensors in the near‐surface concrete of the partial prestressed bridges to reliably survey possible changes.

The measurements on site go along with long‐term laboratory tests on prestressed concrete beams. Researchers study load effects and long‐term environmental influences on two large‐scale model beams, inside and outside the laboratory.

The monitoring system has been working stable as an early warning system for any changes of the structural conditions since 2002. All data are available on line for both the project team and the owner.
Surface Modification of Exfoliated Layered Gadolinium Hydroxide for the Development of Multimodal Contrast Agents for MRI and Fluorescence Imaging
Authors: Yoon Young‐su , Lee Byung‐Il , Lee Kyung Sig , Im Geun Ho , Byeon Song‐Ho , Lee Jung Hee , Lee In Su
Published: September 2009

A novel method for modifying the surface of magnetic‐resonance‐contrasting layered gadolinium hydroxide (LGdH) is developed providing them with water‐ and bio‐compatibility and acid‐resistance, all of which are essential for medical applications. A stable colloid of exfoliated layers is synthesized by exchanging interlayer anions of LGdH with oleate ions. The delaminated layers are successively coated with phospholipids with poly(ethylene glycol) tail groups, and their effectiveness as a contrast agent for magnetic resonance imaging (MRI) is demonstrated. The adaptability of this surface modification approach for incorporating functional molecules and fabricating a fluorescent colloid of LGdH, which has the potential utility as a multimodal probe, is also demonstrated. This result provides a novel approach for expanding the applications of layered inorganic materials and developing a new class of MRI contrast agents.
Modeling the crystallization of proteins and small organic molecules in nanoliter drops
Authors: Dombrowski Richard D. , Litster James D. , Wagner Norman J. , He Yinghe
Published: September 2009

Drop‐based crystallization techniques are used to achieve a high degree of control over crystallization conditions in order to grow high‐quality protein crystals for X‐ray diffraction or to produce organic crystals with well‐controlled size distributions. Simultaneous crystal growth and stochastic nucleation makes it difficult to predict the number and size of crystals that will be produced in a drop‐based crystallization process. A mathematical model of crystallization in drops is developed using a Monte Carlo method. The model incorporates key phenomena in drop‐based crystallization, including stochastic primary nucleation and growth rate dispersion (GRD) and can predict distributions of the number of crystals per drop and full crystal size distributions (CSD). Key dimensionless parameters are identified to quickly screen for crystallization conditions that are expected to yield a high fraction of drops containing one crystal and a narrow CSD. Using literature correlations for the solubilities, growth, and nucleation rates of lactose and lysozyme, the model is able to predict the experimentally observed crystallization behavior over a wide range of conditions. Model‐based strategies for use in the design and optimization of a drop‐based crystallization process for producing crystals of well‐controlled CSD are identified. © 2009 American Institute of Chemical Engineers AIChE J, 2010
Integrated synthesis and extraction of short‐chain fatty acid esters by supercritical carbon dioxide
Authors: Lubary Marta , Jansens Peter J. , ter Horst Joop H. , Hofland Gerard W.
Published: September 2009

We developed an efficient, integrated reaction‐extraction process for the production of short‐chain fatty acid ethyl esters (FAEE) from milk fat, using carbon dioxide as the only processing solvent. FAEE were synthesized using a short‐chain fatty acid selective lipase. The expansion of the liquid mixture of reactants by dense carbon dioxide enhanced the apparent lipase selectivity. In situ extraction of FAEE by a continuous flow of supercritical carbon dioxide proved to increase the lipase production rate. When the integrated process was operated with alternated periods of synthesis and product removal, the overall selectivity for short‐chain FAEE increased as well, as a result of the combination of the selectivities of lipase and extraction solvent. A two‐fold increase of the lipase productivity was achieved at these conditions, compared to a single batch reaction. The developed process enables the synthesis and isolation of high‐value fatty acid derivatives from a natural source such as milk fat. © 2009 American Institute of Chemical Engineers AIChE J, 2009
A neural network critical for spelling
Authors: Cloutman Lauren , Gingis Leila , Newhart Melissa , Davis Cameron , Heidler‐Gary Jennifer , Crinion Jennifer , Hillis Argye E.
Published: September 2009

We aimed to identify neuroanatomical regions associated with deficits to the graphemic buffer, a working memory component of the spelling system that holds the sequence of letter identities during production. We evaluated 331 patients with left hemisphere ischemic stroke with various spelling tests and magnetic resonance diffusion‐weighted imaging and perfusion‐weighted imaging, within 48 hours of stroke onset. A voxel‐wise statistical map showed that ischemia in voxels in posterior and inferior frontal and parietal cortex, subcortical white matter underlying prefrontal cortex, lateral occipital gyrus, or caudate was associated with impairment in maintaining the sequence of letter identities while spelling. Ann Neurol 2009;66:249–253
Treatment disparities in Parkinson's disease
Authors: Dahodwala Nabila , Xie Ming , Noll Elizabeth , Siderowf Andrew , Mandell David S.
Published: September 2009

We sought to identify racial disparities in the treatment of Parkinson's disease (PD). We identified 307 incident PD cases using Pennsylvania State Medicaid claims, and extracted claims for medications, physical therapy, and healthcare visits for the 6 months after diagnosis. After controlling for age, sex, and geography, African‐Americans were four times less likely than whites to receive any PD treatment (odds ratio, 0.24; 95% confidence interval, 0.09–0.64), especially indicated medications. In a group with the same healthcare insurance, disparities in PD treatment exist. Physician and community awareness of these racial differences in PD treatment is the first step in addressing healthcare disparities. Ann Neurol 2009;66:142–145
Assessment drives learning: An unavoidable truth?
Authors: Wormald Benjamin W. , Schoeman Scarpa , Somasunderam Arnold , Penn Michelle
Published: September 2009

The debate around which factors drive medical students' learning is ongoing and controversial. What is the influence of an assessment's weighting on the motivation of students to study the particular subject? One medical school in London is in a unique position to investigate this question. At our institution, the weighting of Anatomy within the overall scheme of assessment has changed twice in recent years, a trend of increased weighting. This enabled a comparative investigation into the effect these changes have had on the students' motivation to learn Anatomy. A five‐point Likert‐scale questionnaire survey was used to evaluate students. A section within a broad survey of Anatomy teaching and learning at our institution was dedicated to the evaluation of the amount of weighting Anatomy received within the assessment structure and the effect this had on students' motivation toward learning the subject. Increasing Anatomy's weighting within the scheme of assessment produced a dramatic increasing trend toward students' motivation to learn Anatomy. The weighting of Anatomy has a profound effect on students' motivation to learn it. Although multifactorial and complex in nature, medical students' self‐reported drive to study a subject is directly influenced by the weighting of the subject in the overall scheme of assessment. Anat Sci Educ 2:199–204, 2009. © 2009 American Association of Anatomists.
Quantitative and qualitative changes in teaching histology by means of virtual microscopy in an introductory course in human anatomy
Authors: Husmann Polly R. , O'Loughlin Valerie Dean , Braun Mark W.
Published: September 2009

This study compares overall laboratory averages and individual test scores along with a student survey to determine the effects of using virtual microscopy in place of optical microscopes in a large undergraduate human anatomy course. T‐tests revealed that the first two laboratory examinations (of four) and the overall laboratory averages were significantly increased compared with the previous year. We hypothesize that this is due to students' ability to use and understand the technology quickly as opposed to learning how to maneuver an optical microscope. Students also responded positively in a survey about the virtual microscope, indicating that increased accessibility, ease of use, and the ability to understand the material were important components of the virtual microscope. In addition, an increase in student collaboration was noted because multiple students were able to view the image at a time. This level of acceptance of virtual microscopy has been reported in previous studies, though this level of increased examination scores is rare. We attribute this to differences between the medical students, with whom this technology has been researched in the past, and undergraduate introductory students. Anat Sci Educ 2:218–226, 2009. © 2009 American Association of Anatomists.
High‐performance liquid chromatographic analysis: applications to nutraceutical content and urinary disposition of oxyresveratrol in rats
Authors: Bertram Rebecca M. , Takemoto Jody K. , Remsberg Connie M. , Vega‐Villa Karina R. , Sablani Shyam , Davies Neal M.
Published: September 2009

A high‐performance liquid chromatographic (HPLC) method was developed for the analysis of the stilbene, oxyresveratrol. This method involves the use of a Luna® C18 column with ultraviolet detection at 320 nm. The mobile phase consisted of acetonitrile, water and formic acid (30 : 70 : 0.04 v/v) with a flow rate of 0.6 mL/min. The calibration curves were linear over the range of 0.5–100.0 μg/mL. The mean extraction efficiency was between 98.9 and 109%. The precision of the assay was 0.069–18.4% (RSD%), and within 20% at the limit of quantitation (0.5 μg/mL). The bias of the assay was <15% and within 15% at the limit of quantitation. This assay was successfully applied to pre‐clinical pharmacokinetic samples from rat urine and to nutraceutical product analysis. Copyright © 2009 John Wiley & Sons, Ltd.
Influence of number of calibration standards within a defined range on pharmacokinetic disposition—case studies with omeprazole and clopidogrel carboxylic acid
Authors: D'Souza Henry John Baptist , Pai Balakrishna , Kumar Anil , Shekar Radha , Srinivas Nuggehally R. , Kristjansson Fjalar
Published: September 2009

While the practice of using a smaller number of non‐zero standards (typically seven to eight) has not been entertained in routine bioanalytical work, it is important to innovate and be pragmatic about minimizing the number of calibration standards to promote cost‐effective and speedy assessment. In this exercise, two important compounds, omeprazole and clopidogrel carboxylic acid, were considered. Additionally, both analytes offered a 1000‐fold calibration curve range with eight non‐zero standards to permit a systematic evaluation. Accordingly various scenarios of post‐hoc analysis of the calibration data were formulated which included step‐wise reduction of the number of calibration standards from a maximum of n = 8 to a minimum of n = 3. In all the scenarios evaluated in this exercise, a calibration curve was reconstructed and both quality control samples and in vivo pharmacokinetics were calculated in each instance. Based on the data generated in this exercise, a minimum of three non‐zero calibration standards were adequate to predict the quality control samples with the predefined accuracy and precision estimates for both omeprazole and clopidogrel carboxylic acid. Additionally, the in vivo pharmacokinetic characterization of the chosen compounds was not hampered by the reduction of calibration standards (from n = 8 to n = 3). Hence, consideration for reducing number of calibration standards in bioanalytical work may provide a viable alternative in several situations such as formulation screening strategies, routine therapeutic drug monitoring and sparse sample analyses. Copyright © 2009 John Wiley & Sons, Ltd.
Determination of intracellular glutathione and cysteine using HPLC with a monolithic column after derivatization with monobromobimane
Authors: Conlan Xavier A. , Stupka Nicole , McDermott Geoffrey P. , Francis Paul S. , Barnett Neil W.
Published: September 2009

An optimized high‐performance liquid chromatography (HPLC) method is used to show that, as myoblasts differentiate into multinucleated muscle fibers, there is a shift to a more oxidized cell redox state. The HPLC method incorporated derivatization with monobromobimane for the determination of the reduced (GSH) and oxidized (GSSG) forms of glutathione and the reduced (Cys) and oxidized (CysSS) forms of cysteine. The derivatization was optimized to improve the sensitivity of the approach; the limits of detection for glutathione and cysteine were 3 × 10−8 and 5 × 10−8 M, respectively. Copyright © 2009 John Wiley & Sons, Ltd.
Genetic modification of the marine‐derived yeast Yarrowia lipolytica with high‐protein content using a GPI‐anchor‐fusion expression system
Authors: Wang Fang , Yue Lixi , Wang Lin , Madzak Catherine , Li Jing , Wang Xianghong , Chi Zhenming
Published: September 2009

Yarrowia lipolytica SWJ‐1b isolated from the marine fish gut was found to contain 47.6 g of crude protein per 100 g of cell dry weight and had potential use as single cell protein. When the gene encoding enhanced green fluorescent protein (EGFP) was inserted into the surface display plasmid pINA1317‐YlCWP110 and expressed in uracil mutant of Y. lipolytica SWJ‐1b, the corresponding protein was successfully displayed on the cell surface, and 100% of the yeast cells exhibited the anchored target proteins. We found that yeast cells displaying EGFP were similar to those of Y. lipolytica SWJ‐1b. Furthermore, C18:1 and C18:3 fatty acids biosynthesis in the marine yeast cells displaying the heterologous EGFP was weakly enhanced compared with that in its wild‐type. The results suggest that the marine‐derived Y. lipolytica SWJ‐1b can be armed with the heterologous protein by the genetic modification and further used as single cell protein. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Imaging chiroptical artifacts
Authors: Freudenthal John H. , Hollis Eva , Kahr Bart
Published: September 2009

It is well‐known that circular dichroism (CD) measurements of anisotropic media may contain artifacts that result from mixed linear anisotropies. Such artifacts are generally considered a nuisance. However, systematic artifacts, carefully measured, may contain valuable information. Herein, polycrystalline spherulites of D‐sorbitol grown from the melt were analyzed with a Mueller matrix microscope, among other differential polarization images devices. As spherulites grew into one another they developed strong apparent optical rotation and CD signals at the boundaries between spherulites. These signals are shown not to have a chiroptical origin but rather resultfrom the interactions of linear anisotropies in polycrystalline bodies. Such chiroptical artifacts should not be dismissed reflexively. Rather, they are comprehensible crystal‐optical effects that serve to define mesoscale structure. Chirality 21:E20–E27, 2009. © 2009 Wiley‐Liss, Inc.
Bile acids in asymmetric synthesis and chiral discrimination
Authors: Bortolini Olga , Fantin Giancarlo , Fogagnolo Marco
Published: September 2009

An overview on the use of bile acid‐based compounds able to catalyze transformations, control the stereochemical course of a given reaction, recognize and bind other molecules, is presented. The recent developments in inclusion discrimination of chiral and achiral guests and enantioselective recognition achieved by bile acid are described with suitable examples. Chirality 2010. © 2009 Wiley‐Liss, Inc.
Viscous behaviour of quaternary fluid solutions at 298.15 K
Authors: Shukla R. K. , Kumar Atul , Singh Neetu , Tiwari Uma Kanti
Published: September 2009

Assuming a quaternary fluid solution to be made up of six binaries, a statistical approach of Flory has been extended to develop the expression for dynamic viscosity of multicomponent system using the concept of absolute rate and free volume approaches of liquid state. A reasonable agreement has been achieved between theory and the experiment for n‐hexadecane + carbon tetrachloride + benzene + n‐hexane quaternary system at 298.15 over a wide range of composition. An attempt has also been made to explain the nature of the molecular interactions, involved in the light of excess thermodynamic functions whose sign and magnitude depend upon the chain length and size of the component liquids.
Apolipoprotein Measurements: Is More Widespread Use Clinically Indicated?
Authors: Davidson Michael H.
Published: September 2009

Apolipoprotein (apo) B may be a more sensitive measure of atherogenicity than low‐density lipoprotein cholesterol (LDL‐C) and a better index for assessing cardiovascular risk. The refined risk assessment provided by apo B may be important in patients at high cardiometabolic risk such as those with diabetes mellitus or metabolic syndrome, as these conditions are often associated with normal LDL‐C values but increased numbers of small, dense low‐density lipoprotein (LDL) particles (indicating increased levels of apo B). Although apo B is not currently a treatment target in the United States cholesterol‐lowering guidelines, a consensus conference endorsed by the American Diabetes Association and the American College of Cardiology recently recommended that apo B be added as a therapeutic target in patients at high cardiometabolic risk and in patients with clinical cardiovascular disease or diabetes. Suggested target goals are < 90 for high risk and < 80 mg/dL for highest risk patients. Current clinical data indicate that intensive statin therapy can lower apo B to meet this aggressive goal. While the proatherogenic/antiatherogenic ratio of apo B/apo A‐I is a better risk discriminator than the single proatherogenic measurement (apo B), clinical trial data are lacking regarding the impact of increasing apo A‐I and high‐density lipoprotein on outcomes. Copyright © 2009 Wiley Periodicals, Inc.
Evolving Cardiovascular Disease Prevalence, Mortality, Risk Factors, and the Metabolic Syndrome in China
Authors: Zheng Yixiu , Stein Richard , Kwan Tak , Yu Christine , Kwan Joanne , Shao‐liang Chen , Hu Dayi
Published: September 2009

The rapid growth transformation of China from a rural agrarian society to an industrial society with increased wealth has impacted the cardiovascular health of the entire population. The increasing prevalence of cardiovascular disease (CVD) and CVD risk factors mirror in some regards the disease prevalence in western industrialized countries and in other areas present unique public health issues. This article reviewed recent population surveys, reports, and clinical trials conducted in China. It was found that the prevalence of CVD and many of the risk factors such as hypertension, obesity, and diabetes contributing to disease mortality are increasing in China. However, compared with the United States, disease mortality is lower. Also, cerebrovascular disease is far more common than ischemic heart disease in China. The low prevalence of disease may suggest a reduced role of diagnostic imaging studies as compared with the US, while the increased percentage of strokes may point to the need for widely available emergent computed tomography (CT) imaging in hospitals in China. This article also discusses the occurrence of metabolic syndrome, obesity, glucose intolerance, diabetes, and their unique features in the Chinese population. Of interest, compared with the Caucasian cohort of the same body mass index (BMI), the Chinese had a higher percentage of body fat. Metabolic syndrome was found to be associated with increased cardiovascular mortality rate. With one fifth of the world's population, China can anticipate a dramatic rise, in absolute numbers, of CVD. It is imperative that national and regional programs are initiated to detect and treat the disease. Copyright © 2009 Wiley Periodicals, Inc.
Hemodynamics, Diuretics, and Nesiritide: A Retrospective VMAC Analysis
Authors: Young James B. , Cheng Mei , Mills Roger M.
Published: September 2009

Hypothesis

Hypotension has been proposed as the cause of nesiritide‐associated increases in serum creatinine (SCr); however, this hypothesis has not been tested.

Methods

This retrospective evaluation of patients who had a pulmonary artery catheter and received nesiritide in the Vasodilation in the Management of Acute Congestive Heart Failure (VMAC) trial assessed hypotension, SCr elevation, concomitant therapy, and mortality. Patients were categorized by baseline pulmonary capillary wedge pressure (PCWP) and analyzed both for overall population and by diuretic dose.

Results

Compared with patients with PCWP > 23 mm Hg (n = 105), patients with PCWP ≤ 23 mm Hg (n = 49) had more hypotension within 24 hours of initiating nesiritide (16% vs 7%), but neither more SCr elevation by nominal day 30 (29% vs 28%) nor higher mortality (30 days: 8.2% vs 7.7%; 6 months: 29.0% vs 29.3%). The risk of hypotension was directly related to high dose diuretics (25% vs 6%; relative risk [RR]: 4.2; 95% confidence interval [CI]: 1.10–15.82) and was not significantly increased in patients without this concomitant treatment (10% vs 7%; RR: 1.4; 95% CI: 0.34–5.93). Additionally, high dose diuretics significantly increased the risk of SCr elevation (RR: 2.6; 95% CI: 1.03–6.64) and 6 month mortality (hazard ratio: 3.6; 95% CI: 1.19–10.63) in patients with PCWP ≤ 23 mm Hg.

Conclusions

Hypotension is not the primary etiology for nesiritide‐associated increases in SCr. High dose diuretics increase the risk of adverse outcomes in patients with PCWP ≤ 23 mm Hg and should be reserved for patients in whom PCWPs are known to be markedly elevated. Copyright © 2009 Wiley Periodicals, Inc.
Angiotensin Receptor Blocker Therapy for Heart Failure Patients: Is Combination Treatment a Feasible Prospect?
Authors: Mehta P.A. , McDonagh S. , Phillips J. , Grocott‐Mason R. , Dubrey S.W.
Published: September 2009

Background

The addition of the angiotensin II type 1 receptor blocker (ARB) candesartan to a angiotensin‐converting enzyme inhibitor (ACEI) has been associated with improved clinical outcomes in patients with heart failure. However many do not tolerate combination therapy and concerns have been raised regarding excessive neurohormonal inhibition.

Hypothesis

The majority of patients with chronic heart failure are not eligible or do not tolerate combination therapy with an ACEEI and ARB.

Methods

We prospectively evaluated 115 consecutive patients with heart failure (median age 74 y; 74% males; mean left ventricular ejection fraction 30%) within a district general hospital for eligibility and tolerance to combination therapy using candesartan in addition to recommended doses of an ACEI.

Results

Overall, 109 (95%) were ineligible to initiate candesartan. The most frequent reasons were that, despite best efforts at optimization, 77% of patients were unable to achieve recommended doses of an ACEI, 29% were relatively asymptomatic, 20% had symptomatic hypotension, and 35% were already taking an ARB due to previous ACEI “intolerance.” Overall, 6 (5%) of patients satisfied the eligibility criteria of whom 3 (3% of total) were already taking “optimal” doses of an ARB in addition to an ACEI. The remaining 3 patients commenced the titration schedule with candesartan. All 3 patients failed the first titration phase (4 mg once daily) within 2 weeks of initiation, due to the development of hyperkalemia.

Conclusions

The use of combination therapy with an ARB in addition to recommended doses of ACEI does not appear feasible in patients with heart failure in the general population, as the vast majority are not eligible. Copyright © 2009 Wiley Periodicals, Inc.
Long‐Term Clinical Outcomes After Angiographically Defined Very Late Stent Thrombosis of Drug‐Eluting Stent
Authors: Kim Ung , Kim Dong‐Kie , Kim Young‐Bok , Seol Sang‐Hoon , Yang Tae‐Hyun , Kim Dae‐Kyeong , Kim Doo‐Il , Kim Dong‐Soo , Lee Sang‐Hee , Hong Geu‐Ru , Park Jong‐Seon , Shin Dong‐Gu , Kim Young‐Jo , Cho Yoon‐Kyung , Kim Hyung‐Seop , Nam Chang‐Wook , Hur Seung‐Ho , Kim Kwon‐Bae
Published: September 2009

Background

The advent of drug‐eluting stent (DES) use has raised concerns regarding later occurring stent thrombosis, especially very late stent thrombosis (VLST), and little is known about long‐term clinical outcomes after VLST occurrence.

Hypothesis

Long‐term clinical outcomes after detection of VLST may be poor.

Method

We evaluated 3572 consecutive patients who received DES implantation from May 2004 to July 2007 at 3 hospitals. The primary outcomes were a composite of major adverse cardiac events (MACE) including cardiac death, myocardial infarction (MI), target‐lesion revascularization (TLR), and target‐vessel revascularization (TVR) after VLST occurrence.

Results

We identified 19 patients (0.53%) with angiographically documented stent thrombosis developing over 1 year after DES implantation. The mean time to VLST occurrence was 899 days (899 ± 353). Discontinuation of antiplatelet drugs was noted in 4 (21%) patients and the average duration of discontinuation was 4 days. Clinical presentations of VLST were mainly MI (17 patients, 89%). Balloon angioplasty was only performed in 12 patients (63%) and stent implantation in 7 patients (37%). Mean follow‐up duration from VLST occurrence was 620 days (620±256). During clinical follow‐up after VLST occurrence, no cardiac deaths or MIs were detected. Target‐vessel revascularization was done in 2 (11%) patients and TLR in 1 patient (6%). Major adverse cardiac events occurred in 3 (16%) patients during long‐term clinical follow‐up.

Conclusions

Clinical presentation of VLST after DES implantation is associated with serious adverse events, such as MI. Long‐term follow‐up outcomes after VLST occurrence appear unfavorable and more data from larger studies are warranted. Copyright © 2009 Wiley Periodicals, Inc.
Oxygen Therapy–Use and Abuse in Acute Myocardial Infarction Patients
Authors: Richard Conti C.
Published: September 2009

In August 2008, an article was published in Heart entitled, “The Routine Use of Oxygen in the Treatment of Myocardial Infarction.”1 This article stimulated me to opine on this topic, which has been an interest of mine for many years. Copyright © 2009 Wiley Periodicals, Inc.
Growth and dissolution kinetics of potassium sulfate in pure solutions and in the presence of Cr3+ ions
Authors: Gougazeh M. , Omar W. , Ulrich J.
Published: September 2009

The growth and dissolution kinetics of potassium sulfate was studied based on single crystal measurements. The growth rate is correlated to the supersaturation with power low equation. At all the temperatures studied, the growth rate order lies in the range of 1‐1.5 with the surface integration process as the controlling step. The estimated value of the activation energy of growth is 39.4 kJ/mol. The dissolution rate order decreases with increasing the temperature. The diffusion step is controlling the dissolution process. The addition of 5 ppm Cr3+ ions reduces the growth rate. Both growth rate dispersion and dissolution rate dispersion occur in the growth and dissolution processes of potassium sulfate. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Minerals as advanced materials
Authors: Depmeier W.
Published: September 2009

A resume is given on relationships between minerals and materials. It is shown that Nature has many advantages over technology which can be profitably exploited for finding new materials with useful properties. However, Nature has also inherent limitations. Therefore, it seems advisable to use the knowledge of minerals as a treasure which can be tapped for getting inspired on the way to finding new materials. Several examples are given, including those of zorite/ETS‐4/ETS‐10, boracites, zircon, kesterite, a natural quasicrystal, opals, ultramarine and mayenite. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spatially resolved X‐ray diffraction as a tool for strain analysis in laterally modulated epitaxial structures
Authors: Wierzbicka A. , Domagala J. Z. , Sarzynski M. , Zytkiewicz Z. R.
Published: September 2009

Spatially resolved X‐ray diffraction (SRXRD) is applied for micro‐imaging of strain in laterally modulated epitaxial structures. In GaAs layers grown by liquid phase epitaxial lateral overgrowth (ELO) on SiO2‐masked GaAs substrates a downward tilt of ELO wings caused by their interaction with the mask is observed. The distribution of the tilt magnitude across the wings width is determined with μm‐scale spatial resolution. This allows measuring of the shape of the lattice planes in individual ELO stripes. If a large area of the sample is studied the X‐ray imaging provides precise information on the tilt of an individual wing and its distribution. In heteroepitaxial GaSb/GaAs ELO layers local mosaicity in the wing area is found. By the SRXRD the size of microblocks and their relative misorientation were analyzed. Finally, the SRXRD technique was applied to study distribution of localized strain in AlGaN epilayers grown by MOVPE on bulk GaN substrates with AlN mask. X‐ray mapping proves that by mask patterning strain in AlGaN layer can be easily engineered, which opens a way to produce thicker, crack‐free AlGaN layers with a higher Al content needed in GaN‐based laser diodes. All these examples show that high spatial and angular resolutions offered by SRXRD makes the technique a powerful tool to study local lattice distortions in semiconductor microstructures. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)