bluuebunny/crossref_metadata_2025 huggingface dataset:
Endoscopic ultrasound‐guided fine‐needle aspiration diagnosis of clear‐cell pancreatic endocrine neoplasm in a patient with von Hippel‐Lindau disease: A case report
Authors: Safo Anthony‐Osei F. , Li Rebecca W. , Vickers Selwyn M. , Schmechel Stephen C. , Pambuccian Stefan E.
Published: February 2009

The cytologic findings of a clear‐cell pancreatic endocrine neoplasm (PEN) diagnosed by endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) occurring in a 29‐year‐old man with von Hippel‐Lindau (VHL) syndrome are described. Imaging studies showed multiple pancreatic masses and cysts, a single liver lesion, and pulmonary and renal cysts. Cytologic features of this clear‐cell PEN included the presence of large sheets and rounded clusters of polygonal neoplastic cells with relatively abundant cytoplasm containing numerous, small, sharply‐demarcated vacuoles that occasionally indented nuclei and gave the cells a “frothy” appearance. Mild anisonucleosis was present and nucleoli were visible. Rare single cells and stripped nuclei were seen. Small vessels transgressed tumor cell sheets. These cytologic findings are distinct from those of typical endocrine neoplasms, and bear resemblance to the cytologic features of renal cell carcinoma metastatic to the pancreas. To the best of our knowledge, this is the first detailed report of the EUS‐FNA cytologic findings of a clear‐cell PEN associated with VHL syndrome. We believe that the distinctive and characteristic cytologic features, together with immunohistochemical studies, can allow a preoperative cytologic diagnosis of this highly unusual pancreatic lesion and avoid possible confusion with other clear‐cell neoplasms in the pancreas, particularly metastatic renal cell carcinoma. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
Evaluation of flow cytometric immunophenotyping and DNA analysis for detection of malignant cells in serosal cavity fluids
Authors: Sayed Douaa M. , EL‐Attar Madiha M. , Hussein Aliaa A. R. Mohamed
Published: February 2009

The serosal cavities are frequent sites of tumor metastasis. The distinction between carcinoma cells, inflammatory cells, and reactive or malignant mesothelial cells can be difficult in cytology. Multicolor flow cytometry (FCM) provides the opportunity to evaluate multiple antigens simultaneously, making it possible to characterize various cell populations. In this study, we aimed to assess the diagnostic accuracy of FCM immunophenotyping and DNA in comparison with serum tumor markers and classic cytology for detection of malignant cells in pleural and ascitic fluids. One hundred and nineteen samples of body cavity fluids were analyzed. Immunophenotyping was performed by four‐color immunofluorescent staining using monoclonal antibodies against Ber‐EP4, cytokeratin, CD3, and CD45. The DNA analysis by FCM was also performed. In addition, serum CA19‐9, CEA, AFP, and CA125 were analyzed. Ber‐EP4 marker had the highest sensitivity (73%) and specificity (95.5%) in the detection of carcinoma cells in serous fluid and correlated with cytology in most of cases (73%). The mean of DI differed statistically in patients with malignant effusions than in benign one. DI showed no difference in fluids due to infiltration of malignant epithelial cells or hematopoitic malignancy or due to hepatocellular carcinoma developing in cirrhotic liver. Thus, flow cytometry appears to aid not only in the detection of malignant cells but also in the characterization of cell type. On the other hand, although DNA ploidy examination had better sensitivity; it had no advantage over conventional cytopathological examination in identification of malignant cells. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
An approach to post‐radical trachelectomy vaginal‐isthmus cytology
Authors: Sauder Kenan , Wilbur David C. , Duska Linda , Tambouret Rosemary H.
Published: February 2009

Radical trachelectomy (RT) is the surgical amputation of the uterine cervix with paracervical lymphadenectomy, performed in reproductive age women to treat invasive squamous‐cell carcinoma or endocervical adenocarcinoma while preserving the uterine corpus for potential child bearing. Post‐RT patient monitoring includes isthmic‐vaginal cytology. This study reviews our experience with liquid based preparation of post‐RT cytology samples. Fifty‐four post‐RT vaginal‐isthmic cytology specimens were reviewed from nine patients, seven with adenocarcinoma, and two with squamous‐cell carcinoma. Five patients had normal (NILM) or normal with reactive changes on all cytology samples. Two patients had isolated squamous abnormalities (atypical squamous‐cells of uncertain significance (ASC‐US) and low‐grade squamous intraepithelial lesion (LSIL)); both follow‐up biopsies were negative. Two patients had repeatedly abnormal specimens interpreted as atypical glandular cells (AGC), one of whom also had a concurrent ASC‐US. Only one sample was tested for high risk human papilloma virus (hrHPV), with negative results. All patients with abnormal cytology went on to have biopsies which were interpreted as benign. The cytology specimens most often interpreted as AGC contained many groups of hyperchromatic crowded glandular cells and/or stromal cells derived from direct sampling of the lower uterine segment. The crowding often limits visualization of all the cells in a group, plus sampled endometrium may harbor mitoses, adding to the atypical appearance.

Cytologists should become familiar with the spectrum of changes in the post‐RT cytology. Testing for hrHPV should be considered for use in the management of abnormal cytology results. Post RT cytology should be compared with presurgical cytology since one would anticipate similarities in post‐RT true positive cases. In particular, a primary diagnosis of adenocarcinoma makes differentiating benign reactive glandular cells from recurrence a critical issue. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
Development of Analogues of 1α,25‐Dihydroxyvitamin D3 with Biased Side‐Chain Orientation: C20 Methylated Des‐C,D‐homo Analogues
Authors: Vrielynck Freek , Van Haver Dirk , Vandewalle Maurits , Verlinden Lieve , Verstuyf Annemieke , Bouillon Roger , Croce Gianluca , De Clercq Pierre
Published: February 2009

The discovery that 1α,25‐dihydroxyvitamin D3 is effective in the inhibition of cellular proliferation and in the induction of cellular differentiation has led to a search for analogues in which these activities and the classical calcemic activity of the hormone are dissociated. In this context, the synthesis and biological evaluation are reported for six CD‐ring modified structural analogues that were conceived so as to enforce a particular orientation of the 25‐hydroxylated side chain. The analogues are characterized by the absence of the C‐ring and the presence of an unnatural six‐membered D‐ring. The biased side‐chain orientations are realized through the stereocontrolled incorporation of methyl substituents at positions C13/C20 and C16/C20. Comparison of the results of the biological evaluation and conformational analysis of the side chain confirms the existence of a relationship between inhibition of MCF‐7 breast cancer cell proliferation and side chain geometry.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
An Amperometric Immunosensor Based on Layer‐by‐Layer Assembly of L‐Cysteine and Nanosized Prussian Blue on Gold Electrode for Determination of Human Chorionic Gonadotrophin
Authors: Wang Jinfen , Yuan Ruo , Chai Yaqin , Yin Bing , Xu Yang , Guan Shu
Published: February 2009

A novel amperometric immunosensor based on L‐cysteine/nanosized Prussian blue bilayer films ({NPB/L‐cys}2) and gold nanoparticles (nano‐Au) was fabricated for determination of human chorionic gonadotrophin (HCG). First, L‐cys and NPB was self‐assembled by layer‐by‐layer (LBL) technology to form {NPB/L‐cys}2 bilayer films on the gold electrode. Subsequently, nano‐Au layer was immobilized on the {NPB/L‐cys}2 bilayer films by electrodepositing gold chloride tetrahydrate and then anti‐HCG was assembly on the nano‐Au layer. Finally hemoglobin (Hb) was employed to block sites against nonspecific binding. With the electrocatalytic ability of Hb and NPB for the reduction of H2O2, the current signal of the antigen‐antibody reaction was amplified and the enhanced sensitivity was achieved. In this study, the assembly process and performance of the immunosensor were characterized by cyclic voltammetry (CV) and the morphology was researched by scanning electron microscopy (SEM). The immunosensor performed a high sensitivity and a wide linear response to HCG in two ranges from 0.5 to 10 mIU/mL and from 10 to 200 mIU/mL with a relatively low detection limit of 0.2 mIU/mL at 3 times the background noise, as well as good stability and long‐term life.
Amperometric Biosensor Based on Immobilization of Oxalate Oxidase in a Mucin/Chitosan Matrix
Authors: Benavidez Tomás E. , Capra Raúl H. , Alvarez Cecilia I. , Baruzzi Ana M.
Published: February 2009

An amperometric electrode for oxalate determination immobilizing the oxalate oxidase in a mucin/chitosan (muc/chit) gel with glutaraldehyde as crosslinking agent is presented. The effect of muc/chit weight ratio and volume percent (vol.%) of glutaraldehyde was studied. A very low dynamic response was observed in the case of 100% chitosan with 5 vol.% crosslinking agent. The addition of mucin to chitosan for enzyme immobilization resulted in a biosensor with much better performance, concerning to dynamic response, sensitivity, and stability, with 75% of the initial response after two months. The ratio muc/chit 70/30 was considered optimum for the immobilization. A slight crosslinking and the incorporation of mucin largely influences the swelling and diffusion of the analyte; a direct effect of these properties on the calibration slope was found; the hydrophilic environment for the biomolecule also favor the enzymatic activity through a higher enzyme‐substrate interaction.
Time domain simulation of soil–foundation–structure interaction in non‐uniform soils
Authors: Jeremić Boris , Jie Guanzhou , Preisig Matthias , Tafazzoli Nima
Published: February 2009

Presented here is a numerical investigation of the influence of non–uniform soil conditions on a prototype concrete bridge with three bents (four span) where soil beneath bridge bents are varied between stiff sands and soft clay. A series of high‐fidelity models of the soil–foundation–structure system were developed and described in some details. Development of a series of high‐fidelity models was required to properly simulate seismic wave propagation (frequency up to 10Hz) through highly nonlinear, elastic plastic soil, piles and bridge structure. Eight specific cases representing combinations of different soil conditions beneath each of the bents are simulated. It is shown that variability of soil beneath bridge bents has significant influence on bridge system (soil–foundation–structure) seismic behavior. Results also indicate that free field motions differ quite a bit from what is observed (simulated) under at the base of the bridge columns indicating that use of free field motions as input for only structural models might not be appropriate. In addition to that, it is also shown that usually assumed beneficial effect of stiff soils underneath a structure (bridge) cannot be generalized and that such stiff soils do not necessarily help seismic performance of structures. Moreover, it is shown that dynamic characteristics of all three components of a triad made up of earthquake, soil and structure play crucial role in determining the seismic performance of the infrastructure (bridge) system. Copyright © 2009 John Wiley & Sons, Ltd.
High‐precision finite element analysis of elastoplastic dynamic responses of super‐high‐rise steel frames
Authors: Ohsaki Makoto , Miyamura Tomoshi , Kohiyama Masayuki , Hori Muneo , Noguchi Hirohisa , Akiba Hiroshi , Kajiwara Koichi , Ine Tatsuhiko
Published: February 2009

A new framework is presented for analysis of dynamic collapse behavior of steel frames using large‐scale parallel finite element method based on the domain decomposition method. The analysis software is based on ADVC as a part of the E‐Simulator that takes advantage of recent development of computer science and high‐performance parallel computing in computational mechanics. By making an analysis model with fine meshing, a complicated sequence of local buckling of columns and beams can be simulated. Numerical results are shown for dynamic collapse analysis of single‐story and 5‐story frame models to show that the global and local behaviors are simultaneously simulated by a high‐precision finite element analysis. Eigenvalue analysis is also carried out for a 31‐story frame to demonstrate that dynamic analysis can be carried out for a structure discretized to solid elements with more than 70 million DOFs. Copyright © 2009 John Wiley & Sons, Ltd.
Detachment and infiltration variations as consequence of regolith development in a Pyrenean badland system
Authors: Nadal‐Romero E. , Regüés D.
Published: February 2009

The Araguás experimental catchment has been monitored to study badland dynamics in the Central Pyrenees. Previous studies of weathering processes within the catchment reported strong regolith dynamics associated with seasonal variations in the temperature and moisture regimes. A preliminary analysis of hydrological response and suspended sediment transport data recorded at a gauging station also demonstrated seasonal trends. The main objective of the present study is to understand the effect of regolith dynamics on sediment detachment and infiltration processes, based on field studies using simulated rainfall. The experiment design was based on seasonal differences in the physical conditions of surface regolith and the general trends of hydro‐sedimentological responses. Rainfall simulations were conducted on small plots using a pressure nozzle. Similar experimental rainfall conditions were set for all plots (rainfall intensity around 45 mm h–1).

The results showed strong variations in the infiltration and detachment responses closely associated with the regolith conditions and crusting development. Infiltration showed seasonal differences in time lag and intensity: average infiltration rates ranged from very low (2·05 mm h–1) to moderated high values (44·04 mm h–1) associated to regolith development conditions. Maximum sediment concentration, as an indicator of particles produced by detachment, also ranged from moderate (3 g l–1) to extreme values (145 g l–1). Mean and minimum infiltration rates showed negative correlations with initial moisture content. Sediment concentration showed a positive correlation with time lag, ponding, and sealing time, and a negative correlation with initial moisture. In terms of seasonal trends, infiltration and erosion responses were relatively stable during spring and autumn, whereas wide variations were recorded in infiltration rates and sediment detachment during summer and winter. As a general conclusion, the obtained results indicate that seasonal differences in detachment and infiltration depend on the nature of regolith development. Copyright © 2009 John Wiley & Sons, Ltd.
On the adjustment for covariates in genetic association analysis: a novel, simple principle to infer direct causal effects
Authors: Vansteelandt Stijn , Goetgeluk Sylvie , Lutz Sharon , Waldman Irwin , Lyon Helen , Schadt Eric E. , Weiss Scott T. , Lange Christoph
Published: February 2009

In genetic association studies, different complex phenotypes are often associated with the same marker. Such associations can be indicative of pleiotropy (i.e. common genetic causes), of indirect genetic effects via one of these phenotypes, or can be solely attributable to non‐genetic/environmental links between the traits. To identify the phenotypes with the inducing genetic association, statistical methodology is needed that is able to distinguish between the different causes of the genetic associations. Here, we propose a simple, general adjustment principle that can be incorporated into many standard genetic association tests which are then able to infer whether an SNP has a direct biological influence on a given trait other than through the SNP's influence on another correlated phenotype. Using simulation studies, we show that, in the presence of a non‐marker related link between phenotypes, standard association tests without the proposed adjustment can be biased. In contrast to that, the proposed methodology remains unbiased. Its achieved power levels are identical to those of standard adjustment methods, making the adjustment principle universally applicable in genetic association studies. The principle is illustrated by an application to three genome‐wide association analyses. Genet. Epidemiol. 33:394–405, 2009. © 2009 Wiley‐Liss, Inc.
Measurement of cortical thickness from MRI by minimum line integrals on soft‐classified tissue
Authors: Aganj Iman , Sapiro Guillermo , Parikshak Neelroop , Madsen Sarah K. , Thompson Paul M.
Published: February 2009

Estimating the thickness of the cerebral cortex is a key step in many brain imaging studies, revealing valuable information on development or disease progression. In this work, we present a framework for measuring the cortical thickness, based on minimizing line integrals over the probability map of the gray matter in the MRI volume. We first prepare a probability map that contains the probability of each voxel belonging to the gray matter. Then, the thickness is basically defined for each voxel as the minimum line integral of the probability map on line segments centered at the point of interest. In contrast to our approach, previous methods often perform a binary‐valued hard segmentation of the gray matter before measuring the cortical thickness. Because of image noise and partial volume effects, such a hard classification ignores the underlying tissue class probabilities assigned to each voxel, discarding potentially useful information. We describe our proposed method and demonstrate its performance on both artificial volumes and real 3D brain MRI data from subjects with Alzheimer's disease and healthy individuals. Hum Brain Mapp 2009. © 2009 Wiley‐Liss, Inc.
Age effects on the regulation of adult hippocampal neurogenesis by physical activity and environmental enrichment in the APP23 mouse model of Alzheimer disease
Authors: Mirochnic Sebastian , Wolf Susanne , Staufenbiel Matthias , Kempermann Gerd
Published: February 2009

An active lifestyle is to some degree protective against Alzheimer's disease (AD), but the biological basis for this benefit is still far from clear. We hypothesize that physical and cognitive activity increase a reserve for plasticity by increasing adult neurogenesis in the hippocampal dentate gyrus (DG). We thus assessed how age affects the response to activity in the murine APP23 model of AD compared with wild type (WT) controls and studied the effects of physical exercise (RUN) and environmental enrichment (ENR) in comparison with standard housing (CTR) at two different ages (6 months and 18 months) and in both genotypes. At 18 months, both activity paradigms reduced the hippocampal human Aβ1‐42/Aβ1‐40 ratio when compared with CTR, despite a stable plaque load in the hippocampus. At this age, both RUN and ENR increased the number of newborn granule cells in the DG of APP23 mice when compared with CTR, whereas the levels of regulation were equivalent to those in WT mice under the same housing conditions. At 6 months, however, neurogenesis in ENR but not RUN mice responded like the WT. Quantifying the number of cells at the doublecortin‐positive stage in relation to the number of cells on postmitotic stages we found that ENR overproportionally increased the number of the DCX‐positive “late” progenitor cells, indicative of an increased potential to recruit even more new neurons. In summary, the biological substrates for activity‐dependent regulation of adult hippocampal neurogenesis were preserved in the APP23 mice. We thus propose that in this model, ENR even more than RUN might contribute to a “neurogenic reserve” despite a stable plaque load and that age affects the outcome of an interaction based on “activity.” © 2009 Wiley‐Liss, Inc.
Kinetics of atrazine biodegradation by suspended and immobilized mixed microbial cells cultivated in continuous systems
Authors: Tafoya‐Garnica Angélica , Macías‐Flores Alberto , Ruiz‐Ordaz Nora , Juárez‐Ramírez Cleotilde , Galíndez‐Mayer Juvencio
Published: February 2009

BACKGROUND: Using a suspended or immobilized microbial community obtained through chemostat selection from agricultural soils formerly treated with triazinic herbicides, the atrazine biodegradation kinetics in continuous aerobic reaction systems was studied.

RESULTS: When microbial cells were continuously cultivated on atrazine as the sole nitrogen and carbon source, atrazine removal efficiencies ηATZ near to 100% were reached, although accumulation of metabolic byproducts was detected. The fluidized‐bed biofilm reactor allowed atrazine removal rates RV, ATZ higher than that permitted by suspended cell cultures with similar removal efficiencies. In this system, the highest volumetric removal rate was obtained (RV, ATZ = 12.2 mg L−1 h−1), with herbicide removal efficiencies ηATZ near 100% and reduced accumulation of byproducts.

CONCLUSIONS: With the operational conditions probed in continuous suspended‐cell culture, increasing the C:N ratio in the inflowing medium resulted in higher cell growth yields but not in better atrazine removal rates. Kinetic results showed that for similar working conditions higher RV, ATZ values and reduced amounts of degradation byproducts of recalcitrant organic compounds could be expected with multi‐stage biofilm reactors. Copyright © 2009 Society of Chemical Industry
Blood cultures for community‐acquired pneumonia: Are they worthy of two quality measures? A systematic review
Authors: Afshar Nima , Tabas Jeffrey , Afshar Kia , Silbergleit Robert
Published: February 2009

BACKGROUND:

Obtaining blood cultures (BCs) for patients hospitalized with community‐acquired‐pneumonia (CAP) has been recommended by experts and used as a measure of quality of care. However, BCs are infrequently positive in these patients and their effect on clinical management has been questioned.

PURPOSE:

We performed a systematic review of the literature to determine the impact of BCs on clinical management in CAP requiring hospitalization and thus its appropriateness as a quality measure.

DATA SOURCES:

We searched MEDLINE, MEDLINE In‐Process, and the Cochrane databases for English‐language studies that reported the effect of BCs on management of adults hospitalized with CAP. We also searched the reference lists of included studies and background articles and asked experts to review our list for completeness.

STUDY SELECTION:

Studies were chosen if they included adults admitted to the hospital with CAP, BCs were obtained at admission, and BC‐directed management changes were reported.

DATA EXTRACTION:

We abstracted study design, BC positivity, and frequency of BC‐directed management changes.

DATA SYNTHESIS:

Fifteen studies, all with observational cohort design, were identified and reviewed. Two included only patients with BCs positive for pneumococcus, yielding 13 studies for the primary analysis. BCs were true‐positive in 0% to 14% of cases. They led to antibiotic narrowing in 0% to 3% of patients and to antibiotic broadening ultimately associated with a resistant organism in 0% to 1% of patients.

CONCLUSIONS:

BCs have very limited utility in immunocompetent patients hospitalized with CAP. Pneumonia quality measures that include BCs should be reassessed. Journal of Hospital Medicine 2009;4:112–123. © 2009 Society of Hospital Medicine.
Quantitative volatile metabolite profiling of common indoor fungi: relevancy for indoor air analysis
Authors: Schuchardt Sven , Kruse Hermann
Published: February 2009

Microorganisms such as bacteria and molds produce an enormous variety of volatile metabolites. To determine whether typical microbial volatile metabolites can be used as indicator compounds for the detection of hidden mold in indoor environments, we examined 14 typical indoor fungal strains for their growth rates and their capability to produce volatile organic compounds (VOC) on standard clinical media and on agar medium made from building materials. Air samples from Headspace Chambers (HSC) were adsorbed daily on Tenax TA tubes and analyzed by thermal desorption gas chromatography and mass spectrometry. In parallel, metabolic activity was measured by determining oxygen demand, the microbial biomass was assessed by dry weighing. Profiling of the volatile metabolites showed that VOC production depended greatly on fungal strain, culture medium, biological activity, and time. The laboratory‐derived maximum emission rates were extrapolated to approximate indoor air concentrations in a hypothetical mold‐infested room. The extrapolated indoor air data suggest that most of the microbial‐produced VOC concentrations were below the analytical detection limit for conventional indoor air analysis. Additionally, conducted indoor air analysis in mold homes confirmed these findings for the most part. The present findings raise doubts about the utility of indicator VOC for the detection of hidden mold growth in indoor environments. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Genotypic and phenotypic characterization of Lactobacillus plantarum strains isolated from Thai fermented fruits and vegetables
Authors: Tanganurat Winee , Quinquis Benoit , Leelawatcharamas Vichien , Bolotin Alexander
Published: February 2009

Ten Lactobacillus strains originally isolated from Thai fruits and vegetables fermentation were characterized by various phenotypic and genotypic methods. The phenotypic analysis using the method of carbohydrate fermentation patterns (API50CHL) revealed that the isolates belonged to the L. plantarum species. This was further confirmed by 16S rRNA gene sequencing. Multilocus sequence typing (MLST) revealed a strongly clonal population structure and a low genotypic diversity in this collection. However, the analyzed L. plantarum population demonstrated a higher level of diversification after API50CHL that reflects the role of available carbohydrate sources in bacterial evolution. Our results support the postulate that a combination of conventional biochemical and genotyping methods allows a thorough characterization and identification of isolates. We propose that genotypic characterization could be complemented by biochemical characterization to discriminate L. plantarum strains. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A note on the characterization of bismuth black by Raman microspectroscopy
Authors: Trentelman Karen
Published: February 2009

Inspired by the discovery of bismuth metal used as a pigment in a fifteenth century illuminated manuscript, the identification of bismuth compounds by Raman spectroscopy is investigated. Raman spectra of bismuth metal powder, bismuth (III) sulfide (Bi2S3) and bismuth (III) oxide (α‐Bi2O3) are presented. The influence of excitation laser wavelength is explored, along with the laser‐induced oxidation of bismuth to α‐Bi2O3 and β‐Bi2O3. The implication of these results with respect to the selection of appropriate analytical protocols in the investigation of bismuth pigments in works of art is discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Organic cyclic difluoramino‐nitramines: infrared and Raman spectroscopy of 3,3,7,7‐tetrakis(difluoramino)octahydro 1,5‐dinitro‐1,5‐diazocine (HNFX)
Authors: Weck Philippe F. , Gobin Cédric , Kim Eunja , Pravica Michael G.
Published: February 2009

We present the first vibrational structure investigation of 3,3,7,7‐tetrakis(difluoramino)octahydro‐1,5‐dinitro‐ 1,5‐diazocine (HNFX)—and, more generally, of a member of the new class of gem‐bis(difluoramino)‐substituted heterocyclic nitramine energetic materials—using combined theoretical and experimental approaches. Optimized molecular structure and vibrational spectra of the Ci… symmetry conformer constituting the HNFX crystal were computed using density functional theory methods. Fourier transform infrared and Raman spectra of HNFX crystalline samples were also collected at ambient temperature and pressure. The average deviation of calculated structural parameters from X‐ray diffraction data is ∼1% at the B3LYP/6‐311 + + G(d,p) level of theory, suggesting the absence of significant molecular distortion induced by the crystal field. Very good agreement was found between simulated and measured spectra, allowing reliable assignment of the fundamental normal modes of vibration of the HNFX crystal. Detailed analysis of the normal modes of the C–(NF2)2 and N–NO2 moieties was performed due to their critical importance in the initial steps of the molecular homolytic fragmentation process. Copyright © 2009 John Wiley & Sons, Ltd.
Effects of incorporated amaranth albumins on the functional properties of wheat dough
Authors: Oszvald Mária , Tamás Cecília , Rakszegi Mariann , Tömösközi Sándor , Békés Ferenc , Tamás László
Published: February 2009

BACKGROUND: Recent developments in micro‐scale testing methodology and in methods modelling the effects of native forms of constituents by in vitro methods have provided a new approach to study the impact of added foreign proteins on dough end‐use quality. Amaranth (Amaranthus) is a member of the pseudo‐cereal family, whose storage proteins have superior nutritional quality due to their essential amino acid composition. The aim of this project was to study the effects of the incorporated amaranth albumin proteins on the rheological properties of the wheat dough.

RESULTS: The mixing time requirements, dough strength and stability of the reconstructed dough increased proportionally with the amount (1, 3 and 5%) of amaranth albumin proteins incorporated. These results were supported by measurements on the non‐extractable polymeric protein ratio of the dough indicating the change in polymer size distribution.

CONCLUSION: It was demonstrated that amaranth albumin proteins are capable of interacting with gluten proteins through disulfide bonds, showing similar effects to the individual glutenin subunits of wheat flour proteins. Improvements in dough strength and stability without a substantial increase in the mixing requirements are of great significance for developing energy saving technologies in the baking industry. Copyright © 2009 Society of Chemical Industry
Sample preparation and separation techniques for bioanalysis of morphine and related substances
Authors: Hansen Steen Honoré
Published: February 2009

In present time the use or misuse of morphine and its derivatives are monitored by assaying the presence of the drug and its metabolites in biofluids. In the present review, focus is placed on the sample preparation and on the separation techniques used in the current best practices of bioanalysis of morphine and its major metabolites. However, as methods for testing the misuse of heroin, a morphine derivative, often involve bioanalytical methods that cover a number of other illicit drug substances, such methods are also included in the review. Furthermore, the review also includes bioanalysis in a broader perspective as analysis of plant materials, cell cultures and environmental samples. The review is not intended to cover all publications that include bioanalysis of morphine but is more to be considered a view into the current best practices of bioanalysis of morphine, its metabolites and other related substances.
Nitrite as regulator of hypoxic signaling in mammalian physiology
Authors: van Faassen Ernst E. , Bahrami Soheyl , Feelisch Martin , Hogg Neil , Kelm Malte , Kim‐Shapiro Daniel B. , Kozlov Andrey V. , Li Haitao , Lundberg Jon O. , Mason Ron , Nohl Hans , Rassaf Tienush , Samouilov Alexandre , Slama‐Schwok Anny , Shiva Sruti , Vanin Anatoly F. , Weitzberg Eddie , Zweier Jay , Gladwin Mark T.
Published: February 2009

In this review we consider the effects of endogenous and pharmacological levels of nitrite under conditions of hypoxia. In humans, the nitrite anion has long been considered as metastable intermediate in the oxidation of nitric oxide radicals to the stable metabolite nitrate. This oxidation cascade was thought to be irreversible under physiological conditions. However, a growing body of experimental observations attests that the presence of endogenous nitrite regulates a number of signaling events along the physiological and pathophysiological oxygen gradient. Hypoxic signaling events include vasodilation, modulation of mitochondrial respiration, and cytoprotection following ischemic insult. These phenomena are attributed to the reduction of nitrite anions to nitric oxide if local oxygen levels in tissues decrease. Recent research identified a growing list of enzymatic and nonenzymatic pathways for this endogenous reduction of nitrite. Additional direct signaling events not involving free nitric oxide are proposed. We here discuss the mechanisms and properties of these various pathways and the role played by the local concentration of free oxygen in the affected tissue. © 2009 Wiley Periodicals, Inc. Med Res Rev, 29, No. 5, 683–741, 2009
Panconnectivity and edge‐pancyclicity of k‐ary n‐cubes
Authors: Hsieh Sun‐Yuan , Lin Tsong‐Jie
Published: February 2009

In this article, we study some topological properties of k‐ary n‐cubes Q. We show that each edge in Q lies on a cycle of every length from k to kn. We also show that Q is both bipanconnected and edge‐bipancyclic, where n ≥ 2 is an integer and k ≥ 2 is an even integer. © 2009 Wiley Periodicals, Inc. NETWORKS 2009
A note on the k‐degree Cayley graph
Authors: Tanaka Yuuki , Shibata Yukio
Published: February 2009

The k‐degree Cayley graph has been proposed by Hsieh and Hsiao (Networks 47 (2006), 26–36). They have shown that the k‐degree Cayley graph is actually a Cayley graph. According to their definition, a generating set of that graph was defined implicitly. Therefore, it requires some effort to figure out that such graphs are actually Cayley graphs. In this article, we use the wreath product of groups to show that k‐degree Cayley graphs form a class of Cayley graphs. © 2009 Wiley Periodicals, Inc. NETWORKS, 2009
Searching symmetric networks with Utilitarian‐Postman paths
Authors: Alpern Steve , Baston Vic , Gal Shmuel
Published: February 2009

We introduce the notion of a Utilitarian Postman (UP) path on a network Q as one which minimizes the expected time required to find a random (uniformly distributed) point, and show that UP paths must be used in a minimax search of a symmetric network. For any network Q, one may consider the zero‐sum search game Γ(Q) in which the (minimizing) Searcher picks a unit speed path S(t) in Q, the Hider picks a point H in Q, and the payoff is the meeting time T = min{t : S(t) = H}. We show first that if Q is symmetric (edge and vertex transitive), then it is optimal for the Hider to pick H uniformly in Q, so that the Searcher must follow a UP path. We then show that if Q is symmetric of odd degree, with n vertices and m unit length edges, the value V of Γ(Q) satisfies
$ V \geq {m \over 2} + {n^{2}-2n \over 8m} $, with equality if and only if (*): Q has a path P = v1, v2,…,vn−1 of distinct vertices, such that the edge set Q′ = Q−∪(v2i,v2i+1) is connected. In this case, there is a UP path for Q consisting of P followed by an Eulerian path E of Q′. The condition (*) is satisfied by many symmetric graphs, including all complete graphs, complete bipartite graphs, hypercube graphs, high valency graphs, and the Petersen graph. We know of no odd degree symmetric graph not satisfying (*). © 2009 Wiley Periodicals, Inc. NETWORKS, 2009
Nonconstrained length effects on the compressive behavior of thick laminated composites
Authors: Lin Yung‐Kun , Liu Hsien‐Kuang , Kuo Wen‐Shyong , Chen Yu‐Der
Published: February 2009

This study reports the nonconstrained length effects on the properties of thick woven fabric composites under static compression loading. The materials examined were carbon/epoxy composites laminated with 10, 20, and 30 plies of the woven prepreg. A pressure rolling setup was designed and employed in the present materials to compact the laminate and to remove the air possibly trapped in between the plies. To apply the compressive load, an end‐supported, end‐loaded fixture was used. The end‐supported clamps were designed with different heights at both ends for the tested specimens, such that there are various free lengths (14, 26, 38, and 50 mm) in the central portion of the specimen defined as nonconstrained length. The growth of cracks was monitored and recorded in real‐time by picture and video cameras. The continuous monitoring of the failure progression provides detailed information about the onset and growth of cracks in various specimens under different nonconstrained lengths. Compared with the critical test length, various nonconstrained lengths can result in different loading curves with or without postfailure portion. The influence of the nonconstrained length on modulus, strength, the loss of stiffness, and energy absorption density has been examined. Two major modes of failure are fiber kink‐band and buckling, and the appearance of the modes depends on the nonconstrained length. Finally, the relationships among the nonconstrained length, the resulting properties, and the induced failure modes are discussed. POLYM. COMPOS., 2009. © 2009 Society of Plastics Engineers
LC‐MS analysis of 13,28‐epoxy‐oleanane saponins in Maesa spp. extracts with antileishmanial activity
Authors: Foubert Kenn , Vermeersch Marieke , Theunis Mart , Apers Sandra , Cos Paul , Claeys Magda , Van Puyvelde Luc , Pieters Luc , Maes Louis
Published: February 2009

Introduction

Saponins are natural products that are well known for a wide range of biological activities. For saponins of Maesa balansae, selective antileishmanial activity has been described.

Objective

In view of their pharmacological interest, several Maesa species from the National Botanical Garden of Meise (Belgium) and wild‐grown plants from Vietnam were screened for their antileishmanial potential and saponin content.

Methodology

Different parts of the plants (mainly leaves and twigs) were collected, dried and extracted. Plant extracts were evaluated by liquid chromatography/mass spectrometry (LC‐MS) using electrospray ionisation in the negative ion mode and their saponin content was compared with those of Maesa balansae (maesabalides) and Maesa lanceolata (maesasaponins).

Results

Several Maesa species (M. ambigua, M. argentea, M. brevipaniculata, M. japonica and M. perlarius) showed potent antileishmanial activity (<0.1 µg/mL) and indeed contained known maesasaponins and maesabalides. However the leaves of M. argentea also revealed two new compounds. Two saponins with [M − H]− ions at m/z 1465 and 1477 were characterised. Their mass spectrometric fragmentation pattern revealed a structure that was the same or closely related to maesasaponin V.3 and VI.2, respectively, but had a glycan part with one additional hexose residue.

Conclusion

Several known as well as new saponins from Maesa species active against leishmaniasis were characterised using LC‐MS. Copyright © 2009 John Wiley & Sons, Ltd.
Facile synthesis of one‐to‐one copy of monomer droplet to latex particle via equilibrium stabilized miniemulsion polymerization
Authors: Luo Ying‐Da , Chiu Wen‐Yen , Dai Chi‐An
Published: February 2009

Miniemulsion polymerization has been traditionally used to synthesize latex particles with a high homogenization energy to prepare an oil/water miniemulsion followed by further polymerizations. However, the exact copy of monomer droplets to latex particles depends critically on emulsion formulation, homogenization condition as well as the stability of the miniemulsified droplets after homogenization. In this study, we demonstrated experimentally for the first time that one‐to‐one copy of monomer droplets to latex particles can be synthesized via polymerization of a miniemulsion prepared from a less stringent preparation process including formulation without costabilizer and low homogenization energy. The criterion to obtain narrow size distribution of monomer droplets was established by equilibration of a low energy homogenized emulsion for different keeping time and the bulk homogenized emulsion subsequently phase separated into two layers. Top layer is the polydispersed monomer‐rich phase. The bottom layer is the equilibrium‐stabilized monomer droplet emulsion, in which the size distribution of droplets is narrow. The equilibrium‐stabilized emulsion is stable for days and subsequent polymerization exhibits nearly 100% droplet nucleation. Furthermore, the effect of surfactant/costabilizer and initiator on the one‐to‐one feature for the synthesis of latex particles was investigated in details. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Rheological behavior of gel‐filled raw natural rubber and styrene‐butadiene rubber with reference to gel‐matrix intermixing
Authors: Mitra Suman , Chattopadhyay Santanu , Sabharwal Sunil , Bhowmick Anil K.
Published: February 2009

Natural rubber (NR) and styrene‐butadiene rubber (SBR) latex gels were prepared by sulfur prevulcanization technique with varying amounts of curing agent and accelerator systems to generate gradient in crosslink density. These gels were characterized by solvent swelling, dynamic light scattering, atomic force microscopy, and mechanical properties. Crosslinked NR gels were intermixed with neat SBR matrix and vice versa. Rheological behavior of chemically crosslinked gel‐filled NR and SBR was studied by capillary rheometry. Intermixing of crosslinked gels in the rubber matrices resulted in a considerable reduction in apparent shear viscosity and die swell values. This behavior was found to be dependent on several factors like gel concentration in the matrix, crosslink density of the gels, their size, and distribution. The effect of temperature on viscosity was studied extensively following the Arrhenious‐Eyring model. A shear rate‐temperature superposition mastercurve was constructed to predict the melt viscosities of the systems as a function of temperature. The change in die swell values was related to the change in first normal stress difference. The scanning electron photomicrographs of the extrudates revealed that presence of gels markedly improved the surface roughness of the raw rubbers. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Protein carbonylation in kidney medulla of the spontaneously hypertensive rat
Authors: Tyther Raymond , Ahmeda Ahmad , Johns Edward , Sheehan David
Published: February 2009

Enhanced generation of ROS has been reported in models of hypertension such as the spontaneously hypertensive rat (SHR). Impairment of kidney function has been implicated in development and progression of hypertension, and the renal medulla appears to play an important role in regulating long‐term blood pressure. A key biomarker of oxidative stress is the formation of protein carbonyls, which we set out to characterize in the SHR medulla. We identified 11 proteins that were differentially carbonylated in SHR medulla in comparison to normotensive wistars including enolase 1, catalase, carbonic anhydrase II, transferrin and members of the aldo–keto‐reductase family. This enhanced protein oxidation was not only accompanied by an increase in intracellular iron deposition, but aldo–keto‐reductase activity was also significantly less in SHR medulla than in normotensive Wistars. Oxidative stress appears selectively to target a subset of proteins in SHR kidney and modification of these proteins may in turn contribute to the renopathy associated with hypertension.
Considerations for powering a clinical proteomics study: Normal variability in the human plasma proteome
Authors: Jackson David , Herath Athula , Swinton Jonathan , Bramwell David , Chopra Rajesh , Hughes Andrew , Cheeseman Kevin , Tonge Robert
Published: February 2009

Proteomics is increasingly being applied to the human plasma proteome to identify biomarkers of disease for use in non‐invasive assays. 2‐D DIGE, simultaneously analysing thousands of protein spots quantitatively and maintaining protein isoform information, is one technique adopted. Sufficient numbers of samples must be analysed to achieve statistical power; however, few reported studies have analysed inherent variability in the plasma proteome by 2‐D DIGE to allow power calculations. This study analysed plasma from 60 healthy volunteers by 2‐D DIGE. Two samples were taken, 7 days apart, allowing estimation of sensitivity of detection of differences in spot intensity between two groups using either a longitudinal (paired) or non‐paired design. Parameters for differences were: two‐fold normalised volume change, α of 0.05 and power of 0.8. Using groups of 20 samples, alterations in 1742 spots could be detected with longitudinal sampling, and in 1206 between non‐paired groups. Interbatch gel variability was small relative to the detection parameters, indicating robustness and reproducibility of 2‐D DIGE for analysing large sample sets. In summary, 20 samples can allow detection of a large number of proteomic alterations by 2‐D DIGE in human plasma, the sensitivity of detecting differences was greatly improved by longitudinal sampling and the technology was robust across batches.
Effects of Fe3O4 underlayer on the annealing temperature of CoFe2O4 thin films
Authors: Zhong Zhiyong , Zhang Huaiwu , Tang Xiaoli , Jing Yulan , Jia Lijun , Liu Shuang
Published: February 2009

CoFe2O4 films of 100 nm thickness were deposited on 20 nm, rf magnetron‐sputtered Fe3O4 underlayers on naturally oxidized Si (100) substrates. These films were then annealed, and the magnetic properties and microstructures were investigated as a function of annealing temperature. Results show that the optimum annealing temperature to obtain the maximum coercivity decreases from 700 °C for films without Fe3O4 underlayers to 500 °C for films with underlayers. The decreased annealing temperature corresponds to a phase transformation of the Fe3O4 underlayers at about 400–500 °C, which accelerates the increase in grain size of the cobalt ferrite films. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Studies of thin microwires with enhanced magnetic softness and GMI effect
Authors: Zhukov A. , Ipatov M. , Blanco J. M. , Gonzalez J. , Zhukova V.
Published: February 2009

In this paper we studied the hysteresis loop and GMI effect (real component of impedance, Z, and the off‐diagonal impedance tensor ζϕz (Hex)) in ultra‐thin amorphous glass‐coated microwires with nearly‐zero and negative magnetostriction constant with metallic nucleus diameter ranging from 6 μm to 16 μm paying special attention to the effect of the metallic nucleus diameter on the aforementioned properties. Both GMI effect and hysteresis loops of nearly‐zero magnetostrictive Co67.1Fe3.8Ni1.4Si14.5B11.5Mo1.7 microwires exhibit strong sensitivity to the ratio, ρ, the metallic nucleus diameter, d, to the total microwire diameter, D. Selecting the right chemical composition we achieved low coercivity (generally below 15 A/m). The magnetic anisotropy field, Hk, increases when ρ decreases. The shape of the magnetic field dependence of Z is also affected by the ρ ‐ratio. The field dependence of the off‐diagonal voltage response of nearly zero magnetostrictive (λs ≈ –3 × 10–7) Co67.1Fe3.8Ni1.4Si14.5B11.5Mo1.7 microwires with metallic nucleus diameters ranging between 6.0 μm and 16.8 μm exhibits anti‐symmetrical shapes. At certain magnetic field, Hm, the off‐diagonal voltage reaches the maximum value. Between –Hm and Hm at certain field range almost linear dependence of the off‐diagonal voltage on magnetic field has been observed. This linear region of the curve depends on microwires geometry, but in any case is smaller than whole –Hm to Hm range. Joule heating significantly affects the off‐diagonal MI curves of Co67.1Fe3.8Ni1.4Si14.5B11.5Mo1.7 microwires with vanishing magnetostriction constant. Under DC current annealing the Hm decreases.

The obtained results allow us to tailor the microwire magnetic properties for applications in magnetic sensors through the selection of their composition and/or thermal treatment conditions. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)