bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduced Glucocorticoid Production Rate, Decreased 5α-Reductase Activity, and Adipose Tissue Insulin Sensitization After Weight Loss
Authors: Tomlinson Jeremy W. , Finney Joanne , Hughes Beverly A. , Hughes Susan V. , Stewart Paul M.
Published: March 2008

OBJECTIVE—The epidemics of obesity, insulin resistance, and type 2 diabetes have heightened the need to understand mechanisms that contribute to their pathogenesis. Increased endogenous glucocorticoid production has been implicated based on parallels with Cushing's syndrome. We have assessed the impact of weight loss on glucocorticoid secretion and metabolism (notably 11β-hydroxysteroid dehydrogenase type 1 and 5α-reductase [5αR] activity) and insulin sensitivity.

RESEARCH DESIGN AND METHODS—Twenty obese volunteers were investigated before and after weight loss. Patients underwent hyperinsulinemic-euglycemic clamps with simultaneous adipose microdialysis and oral cortisone acetate administration. Changes in glucocorticoid secretion and metabolism were assessed using 24-h urine collections.

RESULTS—Before weight loss, fat mass correlated with glucocorticoid secretion rate (total fat, r = 0.46, P < 0.05; trunk fat, r = 0.52, P < 0.05); however, glucocorticoid secretion rate was inversely related to insulin sensitivity (r = −0.51, P < 0.05). Hyperinsulinemia failed to suppress adipose tissue interstitial fluid glycerol release (180 ± 50 μmol [basal] vs. 153 ± 10 μmol [steady state], NS). After oral cortisone (25 mg), cortisol concentrations within adipose interstitial fluid increased (4.3 ± 1.1 vs. 14.2 ± 2.6 nmol/l, P < 0.01), but glycerol concentrations did not change. After weight loss, insulin sensitivity increased. Consistent with insulin sensitization, adipose tissue interstitial fluid glycerol concentrations fell under hyperinsulinemic conditions (186 ± 16 vs. 117 ± 9 μmol, P < 0.05). Glucocorticoid secretion decreased (11,751 ± 1,520 vs. 7,464 ± 937 μg/24 h, P < 0.05) as did 5αR activity (5α-tetrahydrocortisol–to–tetrahydrocortisol ratio 1.41 ± 0.16 vs. 1.12 ± 0.17, P < 0.005).

CONCLUSIONS—Obesity is associated with insulin resistance within adipose tissue and increased cortisol secretion rates; both are reversed with weight loss. Reduced 5αR activity after weight loss may decrease hypothalamo-pituitary-adrenal axis activation and reduce glucocorticoid metabolite production.
Microwave assisted reactions of 2-[3-(Trifluoromethyl)phenyl]-4-R1-furo[3,2-b] pyrrole-5-carboxhydrazides
Authors: Gašparová Renáta , Moncman Martin , Horváth Branislav
Published: March 2008

The effect of microwave irradiation on the reactions of 2-[3-(trifluoromethyl)phenyl]-4-R1-furo[3,2-b]pyrrole-5-carboxhydrazides 1 with 5-arylfuran-2-carboxaldehydes 2, thiophene-2-carboxaldehyde (3) and methyl 2-formylfuro[3,2-b]pyrrole-5-carboxylates 4 has been studied. Reactions of 1 with formic and acetic acid, respectively, led to acylhydrazides 9a–c. Reaction of 1a with 4-substituted 1,3-oxazol-5(4H)-one 10 led to imidazole derivative 13. 1,2,4-Triazole-3-thiones 15a,b were synthesized by two-step reaction of 1a with potassium isothiocyanate and phenyl isothiocyanate, respectively, and subsequent base-catalyzed cyclization of thiosemicarbazides 14a,b. Pyrazole 16 was prepared by reaction of 1a with pentane-2,4-dione.
Spectrofluorometric determination of nicardipine, nifedipine and isradipine in pharmaceutical preparations and biological fluids
Authors: Al-Ghannam Sheikha , Al-Olyan Abeer
Published: March 2008

A simple and highly sensitive spectrofluorometric method was developed for the determination of some 1,4-dihydropyridine compounds namely, nicardipine, nifedipine and isradipine in pharmaceutical preparations and biological fluids. The method is based on the reduction of nicardipine, nifedipine and isradipine with Zn/HCl and measuring the fluorescence intensity obtained (λem/λex) at 460/364, 450/393 and 446/360 nm, respectively. The factors affecting the development of the fluorophore and its stability were studied and optimized. The effect of some surfactants such as β-cyclodextrin (βCD), carboxymethylcelullose (CMC), sodium dodecyl sulphate (SDS) and triton X-100, on the fluorescence intensity was studied. The fluorescence intensity-concentration plots of nicardipine, nifedipine and isradipine were rectilinear over the ranges 0.4–6.0, 0.2–4.0 and 0.1–9.0 μg ml−1 with detection limits of 0.0028, 0.017 and 0.016 μg ml−1, respectively. The proposed method was successfully applied to commercial tablets containing the compounds; the percentage recovery agreed well with those obtained using the official methods. The method was further extended to the in vitro determination of the compounds in spiked human plasma and urine samples. A proposal of the reduction reaction pathway was postulated.
Reference Curves for the Gross Motor Function Measure: Percentiles for Clinical Description and Tracking Over Time Among Children With Cerebral Palsy
Authors: Hanna Steven E , Bartlett Doreen J , Rivard Lisa M , Russell Dianne J
Published: March 2008

Background and Purpose

Physical therapists frequently use the 66-item Gross Motor Function Measure (GMFM-66) with the Gross Motor Function Classification System (GMFCS) to examine gross motor function in children with cerebral palsy (CP). Until now, reference percentiles for this measure were not available. The aim of this study was to improve the clinical utility of this gross motor measure by developing cross-sectional reference percentiles for the GMFM-66 within levels of the GMFCS.

Subjects and Methods

A total of 1,940 motor measurements from 650 children with CP were used to develop percentiles. These observations were taken from a subsample, stratified by age and GMFCS, of those in a longitudinal cohort study reported in 2002. A standard LMS (skewness-median-coefficient of variation) method was used to develop cross-sectional reference percentiles.

Results

Reference curves were created for the GMFM-66 by age and GMFCS level, plotted at the 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, and 97th percentiles. The variability of change in children's percentiles over a 1-year interval also was investigated.

Discussion and Conclusion

The reference percentiles extend the clinical utility of the GMFM-66 and GMFCS by providing for appropriate normative interpretation of GMFM-66 scores within GMFCS levels. When interpreting change in percentiles over time, therapists must carefully consider the large variability in change that is typical among children with CP. The use of percentiles should be supplemented by interpretation of the raw scores to understand change in function as well as relative standing.
Mental Imagery and Affect in English/French Bilingual Readers: A Cross-Linguistic Perspective
Authors: Krasny Karen A. , Sadoski Mark
Published: March 2008

Abstract:

We investigated the evocation of mental imagery and affect in English/French bilinguals to determine whether the linguistic demands of reading in a second language (L2) limit readers’ ability to form non-verbal text representations of literary stories. The participants were 26 Grade 11 French immersion students enrolled in a Canadian high school. Each student read two literary stories, one in English and another in French. Next they rated story paragraphs for the degree of either mental imagery or emotional response evoked. Later, students reread the same texts and completed a writing task in which they reported their imagery or emotions in response to the two highest-rated paragraphs. Moderate to high correlations were found between ratings of imagery and emotional response for each story, for two French stories combined, for two English stories combined, and for all stories in both languages combined. Reading times were somewhat longer for the French versions. The patterns of response for both the ratings and the written reports replicate and extend earlier research and suggest that as bilingual readers progress in their ability to read in their L2, reports of imagery and affect become closer in kind and number to those reported in response to reading the same text in their first language.
Effet de la nature des éléments grammaticaux sur la saisie en français langue seconde
Authors: Simard Daphnée
Published: March 2008

Abstract:

The aim of this study was to examine the interaction between three different syntactic elements and the intake of linguistic information presented in a written text. To attain this objective, young learners (n = 76) of French as a second language read a text containing three targeted syntactic elements. Three experimental conditions were created. In the first group, participants (n = 21) read a text in which the targeted syntactic elements were highlighted using typographical cues. Participants in the second group (n = 29) read the same text, but the syntactic elements targeted by the study were not highlighted. The participants in the third group (n = 26) were not exposed to the text. Intake was operationalized through the results obtained on an error-identification task that the students completed immediately after having been exposed to one of the experimental conditions. The results obtained only partially confirm the study hypothesis, according to which intake product will vary according to the syntactic elements to which the learner is exposed, independent of the experimental condition to which they are exposed.
Stem cell sources and therapeutic approaches for central nervous system and neural retinal disorders
Authors: Yu Diana , Silva Gabriel A.
Published: March 2008

✓ In the past decades, stem cell biology has made a profound impact on our views of mammalian development as well as opened new avenues in regenerative medicine. The potential of stem cells to differentiate into various cell types of the body is the principal reason they are being explored in treatments for diseases in which there may be dysfunctional cells and/or loss of healthy cells due to disease. In addition, other properties are unique to stem cells; their endogenous trophic support, ability to home to sites of pathological entities, and stability in culture, which allows genetic manipulation, are also being utilized to formulate stem cell–based therapy for central nervous system (CNS) disorders. In this review, the authors will review key characteristics of embryonic and somatic (adult) stem cells, consider therapeutic strategies employed in stem cell therapy, and discuss the recent advances made in stem cell–based therapy for a number of progressive neurodegenerative diseases in the CNS as well as neuronal degeneration secondary to other abnormalities and injuries. Although a great deal of progress has been made in our knowledge of stem cells and their utility in treating CNS disorders, much still needs to be elucidated regarding the biology of the stem cells and the pathogenesis of targeted CNS diseases to maximize therapeutic benefits. Nonetheless, stem cells present tremendous promise in the treatment of a variety of neurodegenerative diseases.
Current status of experimental cell replacement approaches to spinal cord injury
Authors: Eftekharpour Eftekhar , Karimi-Abdolrezaee Soheila , Fehlings Michael G.
Published: March 2008

✓ Despite advances in medical and surgical care, the current clinical therapies for spinal cord injury (SCI) are largely ineffective. During the last 2 decades, the search for new therapies has been revolutionized by the discovery of stem cells, which has inspired scientists and clinicians to search for a stem cell–based reparative approaches to many diseases, including neurotrauma. In the present study, the authors briefly summarize current knowledge related to the pathophysiology of SCI, including the concepts of primary and secondary injury and the importance of posttraumatic demyelination. Key inhibitory obstacles that impede axonal regeneration include the glial scar and a number of myelin inhibitory molecules including Nogo. Recent advancements in cell replacement therapy as a therapeutic strategy for SCI are summarized. The strategies include the use of pluripotent human stem cells, embryonic stem cells, and a number of adult-derived stem and progenitor cells such as mesenchymal stem cells, Schwann cells, olfactory ensheathing cells, and adult-derived neural precursor cells. Although current strategies to repair the subacutely injured cord appear promising, many obstacles continue to render the treatment of chronic injuries challenging. Nonetheless, the future for stem cell–based reparative strategies for treating SCI appears bright.
Human embryonic stem cells: a potential source of transplantable neural progenitor cells
Authors: Guillaume Daniel J. , Zhang Su-Chun
Published: March 2008

✓ The primary therapeutic goal of embryonic stem cell (ESC) research is cell replacement therapy. During the last decade, great strides have been made in developing in vitro protocols for differentiating human ESCs into neuroepithelial progenitors. More recent progress has been made in further directing them into becoming cells with specialized regional and neurotransmitter identities, such as midbrain dopaminergic and spinal motor neurons. Along with directed differentiation, other current efforts are aimed at efficient enrichment, avoidance of immune rejection, demonstration of functional integration, genetic modification to regulate neurotransmitter and factor release, directed axon growth, in vivo cell tracking, and measures to ensure safety. This review will focus on the potential of ESCs as a source of transplantable cells for use in cell replacement therapy.
Cellular therapy for childhood neurodegenerative disease. Part I: rationale and preclinical studies
Authors: Guillaume Daniel J. , Huhn Stephen L. , Selden Nathan R. , Steiner Robert D.
Published: March 2008

✓ Successful cellular replacement in the diseased human central nervous system (CNS) faces numerous hurdles. In this first installment of a 2-part review, the authors report on the preclinical challenges involved in preparing for a major Phase I trial investigating the safety of human neural stem cell transplantation in a lysosomal storage disorder. Specifically, they discuss choice of the ideal disease for treatment, best donor cell type and source for implantation, the in vitro and in vivo methods used to estimate safety and efficacy, the challenges to noninvasive tracking of cells after transplantation, and the unique issues related to the immunology of CNS cellular transplantation.
Cellular therapy for childhood neurodegenerative disease. Part II: clinical trial design and implementation
Authors: Selden Nathan R. , Guillaume Daniel J. , Steiner Robert D. , Huhn Stephen L.
Published: March 2008

✓ Cellular replacement therapy attempts to improve functioning of the diseased human central nervous system (CNS). In this second installment of a 2-part review, the authors discuss the major challenges to the translation of in vitro and animal studies of neural stem cell (NSC) therapy in the clinical setting. This analysis details the problems unique to the design of clinical trials using human NSCs, outlines patient selection practices, describes surgical techniques for cellular transplantation, and reviews the regulatory issues and ethical concerns in trials involving neurologically impaired children.
Molecular and cell biology of brain tumor stem cells: lessons from neural progenitor/stem cells
Authors: Xie Zhigang , Chin Lawrence S.
Published: March 2008

✓ The results of studies conducted in the past several years have suggested that malignant brain tumors may harbor a small fraction of tumor-initiating cells that are likely to cause tumor recurrence. These cells are known as brain tumor stem cells (BTSCs) because of their multilineage potential and their ability to self-renew in vitro and to recapitulate original tumors in vivo. The understanding of BTSCs has been greatly advanced by knowledge of neural progenitor/stem cells (NPSCs), which are multipotent and self-renewing precursor cells for neurons and glia. In this article, the authors summarize evidence that genetic mutations that deregulate asymmetric cell division by affecting cell polarity, spindle orientation, or cell fate determinants may result in the conversion of NPSCs to BTSCs. In addition, they review evidence that BTSCs and normal NPSCs may reside in similar vascularized microenvironments, where similar evolutionarily conserved signaling pathways control their proliferation. Finally, they discuss preliminary evidence that mechanisms of BTSC-associated infiltrativeness may be similar to those underlying the migration of NPSCs and neurons.
Survival, differentiation, and migration of bioreactor-expanded human neural precursor cells in a model of Parkinson disease in rats
Authors: Mukhida Karim , Baghbaderani Behnam A. , Hong Murray , Lewington Matthew , Phillips Timothy , McLeod Marcus , Sen Arindom , Behie Leo A. , Mendez Ivar
Published: March 2008

Object

Fetal tissue transplantation for Parkinson disease (PD) has demonstrated promising results in experimental and clinical studies. However, the widespread clinical application of this therapeutic approach is limited by a lack of fetal tissue. Human neural precursor cells (HNPCs) are attractive candidates for transplantation because of their long-term proliferation activity. Furthermore, these cells can be reproducibly expanded in a standardized fashion in suspension bioreactors. In this study the authors sought to determine whether the survival, differentiation, and migration of HNPCs after transplantation depended on the region of precursor cell origin, intracerebral site of transplantation, and duration of their expansion.

Methods

Human neural precursor cells were isolated from the telencephalon, brainstem, ventral mesencephalon, and spinal cord of human fetuses 8–10 weeks of gestational age, and their differentiation potential characterized in vitro. After expansion in suspension bioreactors, the HNPCs were transplanted into the striatum and substantia nigra of parkinsonian rats. Histological analyses were performed 7 weeks posttransplantation.

Results

The HNPCs isolated from various regions of the neuraxis demonstrated diverse propensities to differentiate into astrocytes and neurons and could all successfully expand under standardized conditions in suspension bioreactors. At 7 weeks posttransplantation, survival and migration were significantly greater for HNPCs obtained from the more rostral brain regions. The HNPCs differentiated predominantly into astrocytes after transplantation into the striatum or substantia nigra regions, and thus no behavioral improvement was observed.

Conclusions

Understanding the regional differences in HNPC properties is prerequisite to their application for PD cell restoration strategies.
Vascular endothelial growth factor is associated with histological instability of carotid plaques
Authors: Russell D A , Abbott C R , Gough M J
Published: March 2008

Background

Vascular endothelial growth factor (VEGF) promotes events favouring carotid plaque instability: inflammatory chemoattraction, thrombogenesis, and upregulation of matrix metalloproteinases and cell adhesion molecules. The aim of this study was to assess neovascularization, VEGF and its receptors in high-grade stable and unstable carotid plaques.

Methods

Immunohistochemical staining for CD34, VEGF, VEGF receptor (VEGFR) 1 and VEGFR2 was performed in 34 intact carotid endarterectomy specimens, and compared in sections demonstrating maximal histological instability (cap rupture/thinning) or, if stable, maximal stenosis.

Results

VEGF staining was increased in 12 unstable compared with 22 stable plaques (median (interquartile range, i.q.r.) plaque score 4·0 (4·0–4·0) versus 3·0 (2·0–3·0); P = 0·002) with upregulation of VEGFR1 (plaque score 4·0 (2·0–4·0) versus 2·0 (1·0–3·0); P = 0·016). In unstable plaques this was associated with increased microvessel density in the cap (median (i.q.r.) 12·1 (4·0–30·0) versus 1·1 (0·0–7·3) microvessels/mm2; P = 0·017) and shoulder regions (7·7 (3·4–21·4) versus 3·1 (0·4–10·8) microvessels/mm2; P = 0·176).

Conclusion

Increased VEGF and receptor staining were seen in histologically unstable carotid plaques. Although these differences could reflect cytokine-driven inflammatory events accompanying plaque instability, VEGF and VEGFR1 could be key mediators.
Bioanalytical methods for the determination of antipsychotic drugs
Authors: Zhang Guodong , Jr Alvin V. Terry , Bartlett Michael G.
Published: March 2008

Antipsychotic drugs are popular for the treatment of schizophrenia and other psychoses. In general, antipsychotics are administered in oral doses of only a few milligrams per day and they are widely metabolized in the body. Therefore, the concentration of these drugs in plasma is very low (pg‐ng/mL levels). In addition, therapeutic drug monitoring (TDM) of antipsychotic drugs has proven to be of notable value for determining poor compliance of patients and addressing the challenges associated with considerable genetic variability in their metabolism. Thus, in order to conduct pharmacology and toxicology studies and clinical TDM of antipsychotics, as well as address the challenges associated with polypharmacy and drug metabolism, highly sensitive, selective and accurate bioanalytical methods are essential. The most recent studies on the determination of antipsychotics will be reviewed, including separation techniques, sample pretreatment, detectors and validation. Copyright © 2008 John Wiley & Sons, Ltd.
Serial and single‐victim rapists: differences in crime‐scene violence, interpersonal involvement, and criminal sophistication
Authors: Park Jisun , Schlesinger Louis B. , Pinizzotto Anthony J. , Davis Edward F.
Published: March 2008

Three categories of crime‐scene behaviors (violence, interpersonal involvement, and criminal sophistication) among a group of 22 serial and 22 single‐victim rapists were studied. Findings indicate that serial rapists were more likely to display a higher level of criminally sophisticated behaviors to avoid detection, whereas single‐victim rapists were more likely to behave violently and engage in some form of interpersonal involvement with their victims. Implications of these findings for investigation and for understanding offenders' behavior are discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Anticipatory injustice among adolescents: age and racial/ethnic differences in perceived unfairness of the justice system
Authors: Woolard Jennifer L. , Harvell, M.P.P. Samantha , Graham, Ph.D. Sandra
Published: March 2008

The present study examines age differences in anticipatory injustice, or the expectation of unfair or discriminatory treatment in the legal system. 1,393 adolescents and young adults from the community or from detention centers and jails were interviewed regarding demographic and justice system experience, intelligence, expectations about fair treatment, and legal decisions. African Americans and Latinos and those with more system experience expected greater injustice across multiple legal contexts. Anticipatory injustice increased with age among African Americans and those with the most system experience. It also predicted choices about police interrogation, attorney consultation, and plea agreements. Anticipations of injustice during adolescence may affect future interactions with court officials as well as more general constructs of legal socialization. Copyright © 2008 John Wiley & Sons, Ltd.
Student‐configurable, Web‐accessible virtual systems for system dynamics and controls courses
Authors: Kypuros Javier A. , Connolly Thomas J.
Published: March 2008

This article describes a process for disseminating, via the Internet, configurable animated simulations of physical systems—virtual systems—used to visualize System Dynamics concepts. To enable widespread use, software tools readily available under a General Public License (GPL) are used. However, the dynamic systems are simulated and animated using MATLAB®. © 2008 Wiley Periodicals, Inc. Comput Appl Eng Educ 16: 92–104, 2008; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20125
Open channel design using Visual Basic
Authors: Günal Mustafa , Özcan Atilla
Published: March 2008

This article describes a computer program, which is developed in Visual Basic, for designing open channels. Manning, Darcy–Weisbach, or Hazen–Williams equations can be used to calculate the uniform flow parameters. The program is also able to calculate and draw the surface profile with deciding the profile type of gradually varied flow. © 2008 Wiley Periodicals, Inc. Comput Appl Eng Educ 16: 127–136, 2008; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20131
Synthetic Scope of Ru(OH)x/Al2O3‐Catalyzed Hydrogen‐Transfer Reactions: An Application to Reduction of Allylic Alcohols by a Sequential Process of Isomerization/Meerwein–Ponndorf–Verley‐Type Reduction
Authors: Kim Jung Won , Koike Takeshi , Kotani Miyuki , Yamaguchi Kazuya , Mizuno Noritaka
Published: March 2008

Reduction of allylic alcohols can be promoted efficiently by the supported ruthenium catalyst Ru(OH)x/Al2O3. Various allylic alcohols were converted to saturated alcohols in excellent yields by using 2‐propanol without any additives. This Ru(OH)x/Al2O3‐catalyzed reduction of a dienol proceeds only at the allylic double bond to afford the corresponding enol, and chemoselective isomerization and reduction can be realized under similar conditions. The catalysis is truly heterogeneous and the high catalytic performance can be maintained during at least three recycles of the Ru(OH)x/Al2O3 catalyst. The transformation of allylic alcohols to saturated alcohols consists of three sequential reactions: oxidation of allylic alcohols to α,β‐unsaturated carbonyl compounds; reduction of α,β‐unsaturated carbonyl compounds to saturated carbonyl compounds; and reduction of saturated carbonyl compounds to saturated alcohols.
Synthesis and Properties of DNA Complexes Containing 2,2,6,6‐Tetramethyl‐1‐piperidinoxy (TEMPO) Moieties as Organic Radical Battery Materials
Authors: Qu Jinqing , Morita Ryuhei , Satoh Masaharu , Wada Jun , Terakura Fumiaki , Mizoguchi Kenji , Ogata Naoya , Masuda Toshio
Published: March 2008

We report here the first example of organic radical battery with DNA. Though there is a growing interest in DNA/cationic‐lipid complexes as promising gene delivery vehicles, few efforts have been focused on the use of such complexes as advanced materials for organic optoelectronic applications. The present article describes how substitution of the sodium counter cation of DNA with cationic amphiphilic lipid(1–4) provided novel DNA–lipid complexes that contain TEMPO radicals, in which the actual mole ratio of phosphate to lipid was 1:0.84 to 1:0.16. All the TEMPO‐containing DNA–lipid complexes displayed reversible two‐stage charge/discharge processes, the discharge capacities of which were 40.5–60.0 A h kg−1. In particular, the capacity of a DNA–lipid(3)‐based cell reached 60.0 A h kg−1, which corresponds to 192 % relative to its theoretical value for the single‐electron one‐stage process, indicating a two‐electron process.
Determination of Lead, Iron and Nickel in Water and Vegetable Samples after Preconcentration with Aspergillus niger Loaded on Silica Gel
Authors: Baytak Sıtkı , Koçyiǧit Abdurrahim , Türker Ali Rehber
Published: March 2008

A method for the determination of Fe(III), Pb(II), and Ni(II) by flame atomic absorption spectrometry (FAAS) after preconcentrating on a column containing Aspergillus niger loaded on silica gel 60 (Biosorbent) is described. The effect of experimental parameters such as pH, flow rate of sample solution, and volume of sample solution were investigated on the recovery of the analytes. The effect of interfering ions on the recovery of the analytes has also been investigated. Recoveries of Fe(III), Pb(II), and Ni(II) were (98 ± 2), (98 ± 3), (99 ± 2)% at the 95% confidence level, respectively. For the analytes, 50‐fold preconcentration was obtained. The analytical detection limits for Fe(III), Pb(II), and Ni(II) were 1.7, 5.2, and 1.6 ng/mL, respectively. The proposed method was applied to the determination of trace metals in various water and vegetable samples. The analytes have been determined with relative error lower than 7%.
Systemic therapy for metastatic colorectal cancer
Authors: Zuckerman Dan S. , Clark Jeffrey W.
Published: March 2008

A proliferation of new cytotoxic and biologic agents has led to improved survival in patients with metastatic colorectal cancer (mCRC). The ability of surgery to increase long‐term survival in patients with liver and/or lung metastases also has been firmly established. It has become increasingly difficult as the numbers and types of treatment options have expanded to identify optimal drug combinations, sequences, and duration and the best way to integrate systemic chemotherapy with potentially curative surgery for metastatic lesions. For this review, the authors examined how recent clinical trials have addressed some pertinent questions regarding the use of systemic chemotherapy and biologic agents in patients with mCRC. Cancer 2008. © 2008 American Cancer Society.
Toward replication in grids for digital libraries with freshness and correctness guarantees
Authors: Akal Fuat , Schuldt Heiko , Schek Hans‐Jörg
Published: March 2008

Building digital libraries (DLs) on top of data grids while facilitating data access and minimizing access overheads is challenging. To achieve this, replication in a Grid has to provide dedicated features that are only partly supported by existing Grid environments. First, it must provide transparent and consistent access to distributed data. Second, it must dynamically control the creation and maintenance of replicas. Third, it should allow higher replication granularities, i.e. beyond individual files. Fourth, users should be able to specify their freshness demands, i.e. whether they need most recent data or are satisfied with slightly outdated data. Finally, all these tasks must be performed efficiently. This paper presents an approach that will finally allow one to build a fully integrated and self‐managing replication subsystem for data grids that will provide all the above features. Our approach is to start with an accepted replication protocol for database clusters, namely PDBREP, and to adapt it to the grid. Copyright © 2008 John Wiley & Sons, Ltd.
Parallel query processing for OLAP in grids
Authors: Kotowski Nelson , Lima Alexandre A. B. , Pacitti Esther , Valduriez Patrick , Mattoso Marta
Published: March 2008

OLAP query processing is critical for enterprise grids. Capitalizing on our experience with the ParGRES database cluster, we propose a middleware solution, GParGRES, which exploits database replication and inter‐ and intra‐query parallelism to efficiently support OLAP queries in a grid. GParGRES is designed as a wrapper that enables the use of ParGRES in PC clusters of a grid (in our case, Grid5000). Our approach has two levels of query splitting: grid‐level splitting, implemented by GParGRES, and node‐level splitting, implemented by ParGRES. GParGRES has been partially implemented as database grid services compatible with existing grid solutions such as the open grid service architecture and the Web services resource framework. We give preliminary experimental results obtained with two clusters of Grid5000 using queries of the TPC‐H Benchmark. The results show linear or almost linear speedup in query execution, as more nodes are added in all tested configurations. Copyright © 2008 John Wiley & Sons, Ltd.
A high‐throughput system for segmenting nuclei using multiscale techniques
Authors: Gudla Prabhakar R. , Nandy K. , Collins J. , Meaburn K. J. , Misteli T. , Lockett S. J.
Published: March 2008

Automatic segmentation of cell nuclei is critical in several high‐throughput cytometry applications whereas manual segmentation is laborious and irreproducible. One such emerging application is measuring the spatial organization (radial and relative distances) of fluorescence in situ hybridization (FISH) DNA sequences, where recent investigations strongly suggest a correlation between nonrandom arrangement of genes to carcinogenesis. Current automatic segmentation methods have varying performance in the presence of nonuniform illumination and clustering, and boundary accuracy is seldom assessed, which makes them suboptimal for this application. The authors propose a modular and model‐based algorithm for extracting individual nuclei. It uses multiscale edge reconstruction for contrast stretching and edge enhancement as well as a multiscale entropy‐based thresholding for handling nonuniform intensity variations. Nuclei are initially oversegmented and then merged based on area followed by automatic multistage classification into single nuclei and clustered nuclei. Estimation of input parameters and training of the classifiers is automatic. The algorithm was tested on 4,181 lymphoblast nuclei with varying degree of background nonuniformity and clustering. It extracted 3,515 individual nuclei and identified single nuclei and individual nuclei in clusters with 99.8 ± 0.3% and 95.5 ± 5.1% accuracy, respectively. Segmented boundaries of the individual nuclei were accurate when compared with manual segmentation with an average RMS deviation of 0.26 μm (∼2 pixels). The proposed segmentation method is efficient, robust, and accurate for segmenting individual nuclei from fluorescence images containing clustered and isolated nuclei. The algorithm allows complete automation and facilitates reproducible and unbiased spatial analysis of DNA sequences. Published 2008 Wiley‐Liss, Inc.
High throughput FRET screening of the plasma membrane based on TIRFM
Authors: Paar Christian , Paster Wolfgang , Stockinger Hannes , Schütz Gerhard J. , Sonnleitner Max , Sonnleitner Alois
Published: March 2008

Monitoring protein function with high throughput at individual cell level is of high interest both for basic research and diagnostic applications. For this, following the changes in fluorescence resonance energy transfer (FRET) between a donor/acceptor pair, genetically encoded in the proteins of interest, is a frequently used tool. As proteins attached to or located in the plasma membrane represent a considerable fraction of total proteins, there is a need for high throughput imaging techniques suited for observation of proteins in the cell membrane only. A system is presented, which allows rapid imaging of large areas via total internal reflection fluorescence microscopy (TIRFM) conditions, using a focus‐hold system, multiwavelength excitation and dual color detection. The developed imaging system enables screening of large numbers of cells under TIRFM illumination combined with FRET imaging, thereby providing the means to record, e.g., FRET‐efficiency of a membrane‐associated protein labeled with a donor–acceptor pair. The capability of the system to perform live‐FRET scanning with TIRFM on stoichiometric FRET constructs, reaching throughputs of up to 1,000 cells/s at the optical resolution limit is demonstrated. A comparison with confocal microscopy shows that TIRFM offers a 4.2‐fold advantage in our conditions over confocal microscopy in detecting contributions from membrane‐localized proteins. © 2008 International Society for Advancement of Cytometry
Analytical approach to the optimal adaptation rate of reconfigurable radio networks
Authors: Fraile R. , Monserrat J. F. , Cardona N.
Published: March 2008

Flexible radio resource management schemes are nowadays used within a wide range of systems. However, the optimal selection for their adaptation rate is still an open research issue. This paper presents an analytical approach to such problem, which consists in a combined analysis of the dynamics of the session‐arrival process and the estimation of the mean traffic load from network measurements. From this study, it is concluded that both aspects pose an upper limit on the optimal system adaptation rate, being the most restrictive the one depending on the mean traffic load estimation. A specific procedure for deriving such limit on adaptation rate is provided. It is shown that the derived value directly depends on the mean service duration. The application of the whole analysis is illustrated with an example based on a set of measurements from a live network. Copyright © 2008 John Wiley & Sons, Ltd.
Seed roasting improves the oxidative stability of canola (B. napus) and mustard (B. juncea) seed oils
Authors: Wijesundera Chakra , Ceccato Claudio , Fagan Peter , Shen Zhiping
Published: March 2008

Animal fats and partially hydrogenated vegetable oils (PHVO) have preferentially been used for deep‐frying of food because of their relatively high oxidative stability compared to natural vegetable oils. However, animal fats and PHVO are abundant sources of saturated fatty acids and trans fatty acids, respectively, both of which are detrimental to human health. Canola (Brassica napus) is the primary oilseed crop currently grown in Australia. Canola quality Indian mustard (Brassica juncea) is also being developed for cultivation in hot and low‐rainfall areas of the country where canola does not perform well. A major impediment to using these oils for deep‐frying is their relatively high susceptibility to oxidation, and so any processing interventions that would improve the oxidative stability would increase their prospects of use in commercial deep‐frying. The oxidative stability of both B. napus and B. juncea crude oils can be improved dramatically by roasting the seeds (165 °C, 5 min) prior to oil extraction. Roasting did not alter the fatty acid composition or the tocopherol content of the oils. The enhanced oxidative stability of the oil, solvent‐extracted from roasted seeds, is probably due to 2,6‐dimethoxy‐4‐vinylphenol produced by thermal decarboxylation of the sinapic acid naturally occurring in the canola seed.
Why is it so difficult to produce high‐quality virgin rapeseed oil for human consumption?
Authors: Matthäus Bertrand , Brühl Ludger
Published: March 2008

Virgin rapeseed oil becomes increasingly popular for the consumer because of the pleasant seed‐like and nutty taste and smell. The oils are produced in small and medium‐sized facilities by extraction of rapeseed using only a screw press and purifying the oil by sedimentation or filtration. Thus, the producers have no chance to improve the oil quality if the seed quality is bad. Therefore, it is an art to produce high‐quality virgin rapeseed oil that is accepted by the consumer. The most important step in the production chain of virgin rapeseed oil is the period after harvest until the processing, while extraction of the oilseed and purification has only a minor influence on the oil quality. The paper describes the pitfalls during the production of virgin rapeseed oil which primarily wait for the producer during storage of the seeds. Improper storage conditions result in increased metabolic processes in the seeds and an increase of the populations of microorganisms and insects, which finally leads to the degradation of nutrients and the formation of unpleasant aroma compounds.
Epoxidation of methyl oleate with molecular oxygen in the presence of aldehydes
Authors: Köckritz Angela , Blumenstein Michael , Martin Andreas
Published: March 2008

The epoxidation of methyl oleate with molecular oxygen in the presence of aldehydes was investigated and optimized. Epoxide yields up to 99% were observed in organic solvents. The preponderant radical reaction was started by a single organic radical chain initiator, without using a metal catalyst. The radical character of the reaction was revealed by the concurrent occurrence of trans and cis epoxides and by the prevention of epoxide formation through a radical scavenger. Both branched aldehydes and the linear aldehyde n‐hexanal were well suited in organic solvents. The linear n‐hexanal enabled also a superior epoxide yield of 78% in the green solvent water. The oxidation of high‐oleic sunflower oil under the same conditions with n‐hexanal yielded 39% epoxide groups.
Further Uses of Pyrrole‐Based Dienoxysilane Synthons: A Full Aldol Approach to Azabicyclo[x.2.1]alkane Systems
Authors: Zanardi Franca , Curti Claudio , Sartori Andrea , Rassu Gloria , Roggio Annamaria , Battistini Lucia , Burreddu Paola , Pinna Luigi , Pelosi Giorgio , Casiraghi Giovanni
Published: March 2008

Two racemic 2‐azabicyclo[2.2.1]heptane structures, 15 and 21, and two chiral non‐racemic 6‐azabicyclo[3.2.1]octane representatives, 28 and 36, have been synthesized starting from 1‐(tert‐butoxycarbonyl)‐2‐(tert‐butyldimethylsilyloxy)pyrrole (TBSOP, 5) and suitable ketones, 9, 16, 22 and 29. 2‐Azabicycle 15 was then elaborated to racemic cyclopentane amino acid 38, while 6‐azabicycle 36 served to access the enantiomerically pure normorphan‐type structure 40. For all substrates, a uniform synthetic scheme was implemented based on the combination of two diastereoselective aldol‐type carbon–carbon bond‐forming reactions, the efficiencies of which were secured by appropriate aldol‐stabilizing steps. A mechanistic rationale accounting for the markedly diastereoselective character of the key Mukaiyama aldol reactions between TBSOP and the ketone acceptors has been postulated that involves hetero‐Diels–Alder transition‐state structures in which the preference for endo versus exo addition is governed by the electronic nature of the substituents in the ketone substrates.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Redox Speciation of Inorganic Arsenic in Water and Saline Samples by Adsorptive Cathodic Stripping Voltammetry in the Presence of Sodium Diethyl Dithiocarbamate
Authors: de Carvalho Leandro M. , do Nascimento Paulo C. , Bohrer Denise , Stefanello Raquel , Pilau Eduardo J. , da Rosa Marcelo B.
Published: March 2008

This paper describes a new voltammetric procedure for the inorganic speciation of As(III) and As(V) in water samples. The procedure is based on the chemical reduction of arsenate [As(V)] to arsenite [As(III)] followed by the voltammetric determination of total arsenic as As(III) at the hanging mercury drop electrode (HMDE) by adsorptive cathodic stripping voltammetry (AdCSV) in the presence of sodium diethyl dithiocarbamate (SDDC). The reduction step involved the reaction with a mixture of Na2S2O5 and Na2S2O3 in the concentrations 2.5 and 0.5 mg mL−1, respectively, and the sample heating at 80 °C for 45 min. The linear range for the determination of total arsenic as As(III) in the presence of SDDC was between 5 and 150 μg L−1 for a deposition time of 60 s (r=0.992). A detection limit of 1.05 μg L−1 for total As was calculated for the method in water samples using a deposition time of 60 s. The detection limits of 4.2 μg L−1 and 15.0 μg L−1 for total As in seawater and dialysis concentrates, respectively, were calculated using a deposition time of 60 s. The relative standard deviations calculated were 2.5 and 4.0% for five measurements of 20 μg L−1 As(V) as As(III) in water and dialysis concentrates, respectively, after chemical reduction under optimized conditions. The method was applied for the determination of As(III) and total As in samples of dialysis water, mineral water, seawater and dialysis concentrates. Recovery values between 86.0 and 104.0% for As(III) and As(V) added to the samples prove the satisfactory accuracy and applicability of the procedure for the arsenic monitoring.
Analysis of the essential oil of Senecio vernalis Waldst. & Kit. from Iran
Authors: Nori‐Shargh Davood , Raftari Surour , Deyhimi Farzad
Published: March 2008

The volatile constituents of the aerial parts of Senecio vernalis growing wild in Iran have been characterized by GC–FID and GC–MS. The oil was found to contain 13 components. Altogether, 10 compounds were identified from the aerial parts of this plant, collected during its flowering stage. The oil was rich in spathulenol (37.1%), 1,8‐cineol (19.0%), m‐cymene (16.6%). The other major constituents were isobicyclogermacrenal (15.2%) and α‐phellandrene (3.4%). Copyright © 2008 John Wiley & Sons, Ltd.
Region‐specific expression of immunoregulatory proteins on microglia in the healthy CNS
Authors: de Haas Alexander H. , Boddeke Hendrikus W. G. M. , Biber Knut
Published: March 2008

In accordance with a high degree of spatial organization in the central nervous system (CNS), most CNS diseases display a regional distribution. Although microglia have been established as key players in various CNS diseases, it is not yet clear whether microglia display region‐specific properties. Therefore, this study aimed to evaluate the existence of distinct microglia phenotypes in various regions of the healthy, adult mouse CNS. Using ex vivo flow cytometric analysis surface expression of CD11b, CD40, CD45, CD80, CD86, F4/80, TREM‐2b, MHCII, CXCR3, CCR9, and CCR7 were analyzed. Most of these immunoregulatory markers were found on microglia and showed significant region‐specific differences in expression levels. These findings considerably corroborate the existence of immunological diversity among microglia in the healthy, unchallenged CNS of adult mice. © 2008 Wiley‐Liss, Inc.
The neurophysiological bases of emotion: An fMRI study of the affective circumplex using emotion‐denoting words
Authors: Posner Jonathan , Russell James A. , Gerber Andrew , Gorman Daniel , Colibazzi Tiziano , Yu Shan , Wang Zhishun , Kangarlu Alayar , Zhu Hongtu , Peterson Bradley S.
Published: March 2008

Objective: We aimed to study the neural processing of emotion‐denoting words based on a circumplex model of affect, which posits that all emotions can be described as a linear combination of two neurophysiological dimensions, valence and arousal. Based on the circumplex model, we predicted a linear relationship between neural activity and incremental changes in these two affective dimensions. Methods: Using functional magnetic resonance imaging, we assessed in 10 subjects the correlations of BOLD (blood oxygen level dependent) signal with ratings of valence and arousal during the presentation of emotion‐denoting words. Results: Valence ratings correlated positively with neural activity in the left insular cortex and inversely with neural activity in the right dorsolateral prefrontal and precuneus cortices. The absolute value of valence ratings (reflecting the positive and negative extremes of valence) correlated positively with neural activity in the left dorsolateral and medial prefrontal cortex (PFC), dorsal anterior cingulate cortex, posterior cingulate cortex, and right dorsal PFC, and inversely with neural activity in the left medial temporal cortex and right amygdala. Arousal ratings and neural activity correlated positively in the left parahippocampus and dorsal anterior cingulate cortex, and inversely in the left dorsolateral PFC and dorsal cerebellum. Conclusion: We found evidence for two neural networks subserving the affective dimensions of valence and arousal. These findings clarify inconsistencies from prior imaging studies of affect by suggesting that two underlying neurophysiological systems, valence and arousal, may subserve the processing of affective stimuli, consistent with the circumplex model of affect. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
“Aha!”: The neural correlates of verbal insight solutions
Authors: Aziz‐Zadeh Lisa , Kaplan Jonas T. , Iacoboni Marco
Published: March 2008

What are the neural correlates of insight solutions? To explore this question we asked participants to perform an anagram task while in the fMRI scanner. Previous research indicates that anagrams are unique in that they can yield both insight and search solutions in expert subjects. Using a single‐trial fMRI paradigm, we utilized the anagram methodology to explore the neural correlates of insight versus search solutions. We used both reaction time measures and subjective reports to classify each trial as a search or insight solution. Data indicate that verbal insight solutions activate a distributed neural network that includes bilateral activation in the insula, the right prefrontal cortex, and the anterior cingulate. These areas are discussed with their possible role in evaluation and metacognition of insight solutions, as well as attention and monitoring during insight. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.