bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling thermal performance of gypsum plasterboard‐lined light timber frame walls using SAFIR and TASEF
Authors: Thomas G.
Published: May 2010

Gypsum plasterboard is commonly used as a lining material on lightweight timber or steel framing. Gypsum contains moisture, both free and chemically bound in its crystal structure. The dehydration of the gypsum and decomposition of calcium carbonate absorb heat giving gypsum plasterboard fire resistant qualities. This paper discusses the suitability of the finite element heat transfer program SAFIR for modelling plasterboard‐lined light timber frame assemblies and its limitations. The default material properties in SAFIR for gypsum plasterboard do not give good results and ‘smoothing’ of enthalpy curves has insignificant effects on the results but substantially reduces processing time. Modelling with SAFIR gives similar results to prior modelling using the program TASEF with slight differences. Both programs give better overall results for slower developing fires and furnace tests than more rapidly growing fires. Reasonable, slightly conservative results for thermal analysis of heat transfer through the walls and into timber studs can be achieved using the parameters suggested in this paper. More sophisticated and detailed models incorporating mass transfer, effect of fasteners, gaps between lining sheets and ablation are required to achieve better comparisons. Copyright © 2010 John Wiley & Sons, Ltd.
Synergistic effects of ZrO2 or B2O3 on flame‐retarded poly (butyl methacrylate) with tricresylphosphate
Authors: Wang Xinlong , Song Ye , Bao Jianchun
Published: May 2010

The synergistic flame retarded systems consisting of ZrO2 or B2O3 and tricresylphosphate(TCP) for poly(butyl methacrylate)(PBMA) are reported. The synergistic effects were studied by limited oxygen index (LOI) test, UL‐94, thermal gravimetric analysis (TGA), Infrared Spectroscopy (IR), Raman spectra and digital photos. The synergistic effect of ZrO2 or B2O3 with TCP could be clearly observed by LOI. The TGA results show that ZrO2 or B2O3 increases the char yields of the systems at 500∘C. The Raman spectra, IR and digital photos results provide evidence that ZrO2 or B2O3 can efficiently promote the formation of charred layers composed of varying amounts of graphite and amorphous carbon. The possible mechanisms for synergy are discussed. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis of novolac‐based char former: Silicon‐containing phenolic resin and its synergistic action with magnesium hydroxide in polyamide‐6
Authors: Fei Guoxia , Wang Qi , Liu Yuan
Published: May 2010

Novel novolac‐based char former silicon‐containing phenolic resin (SCPR) was synthesized by the reaction of novolac with γ‐aminopropyltriethoxysilane in ethanol via a dehydration reaction, and the synthesized SCPR was characterized by Fourier transform infrared (FT‐IR) spectra, proton nuclear magnetic resonance (1H NMR) spectroscopy, and thermogravimetric analysis (TGA). Serving as a synergist of magnesium hydroxide (MH) for the flame retardancy of polyamide 6 (PA6), it shows that the introduction of silicon in the structure of novolac molecule can greatly increase the charring performance of phenolic resin, and effectively eliminate the melt drips of PA6, thus improving the flame retardancy of the PA6. Compared with conventional novolac, the thermal oxidative stability of SCPR was obviously enhanced in the presence of MH due to the decrease of phenol hydroxide groups sensitive to oxidation, as well as the high energy Si–O bond introduced in the molecular structure. Copyright © 2010 John Wiley & Sons, Ltd.
Flame spread over porous sand beds wetted with propenol
Authors: Zanganeh Jafar , Moghtaderi Behdad
Published: May 2010

A comprehensive set of experiments was carried out to investigate the spread of flames over porous sand beds wetted with finite quantities of propenol. The aim was to examine the key characteristics of flame propagation over porous beds when a limited supply of liquid fuel to the flame zone was available. Experiments were conducted over beds with depths ranging from 13.3 to 39.9 mm and average particle diameters between 0.5 and 5 mm under quiescent, assisted and opposed airflow configurations. It was found that the flame spread rate for both assisted and opposed airflow configurations dramatically decreased as the air speed was increased although the extent of decay in the flame spread rate was more pronounced in the case of the opposed airflow configuration. The experimental observations were explained by correlating the flame spread rate with the Damköhler number and fuel consumption flux. The practical implications of the findings are briefly discussed in this paper. Copyright © 2010 John Wiley & Sons, Ltd.
Ion current measurements as a tool for ignition detection in the cone calorimeter
Authors: Försth Michael , Larsson Anders
Published: May 2010

Measurements of the ion current between two electrodes have been conducted in order to assess whether the ion current can be used for the detection of ignition in a cone calorimeter, and for fire dynamics investigations in general. The measured ion current clearly indicates when ignition occurs, in agreement with traditional results based on visual inspection. It was also seen that soot deposits on the electrodes do not adversely affect the ability of the ion current to indicate ignition. However, short circuiting may occur if the electrodes are kept in a sooty flame long enough for the soot to completely bridge the gap between the electrodes. The latter scenario is not a problem from an ignition detection point of view since soot growth occurs after ignition has taken place.

Measurement of the ion current between the electrodes was also conducted in a premixed propane flame in order to characterize the dependence of the current on applied voltage and on combustion conditions. The ion current obeys Ohm's law since the current increases linearly with applied voltage in the investigated voltage range. It was also seen that the ion current gave unique results based on its position in a propane flame and the fuel/air ratio of the flame. Copyright © 2010 John Wiley & Sons, Ltd.
A mechanistic method for scrutinising LIFT ignition data
Authors: Tobeck D. O. , Spearpoint M. J. , Fleischmann C. M.
Published: May 2010

The lateral ignition and flame spread test (LIFT) standard (ASTM E 1321‐97a) requires the Thermal Response correlation to be scrutinized for data points that violate the zero heat loss requirement, but the standard gives no guidance on how this should be done. The fundamentals of linear regression were reviewed and an unbiased and mechanistic algorithm for scrutinising LIFT ignition data without human intervention was developed. The algorithm produced reasonable results compared with human interpretation of exemplar test data taken from the literature. Copyright © 2010 John Wiley & Sons, Ltd.
Early event‐related cortical activity originating in the frontal eye fields and inferior parietal lobe predicts the occurrence of correct and error saccades
Authors: Ptak Radek , Camen Christian , Morand Stéphanie , Schnider Armin
Published: May 2010

Although the cortical circuitry underlying saccade execution has well been specified by neurophysiological and functional imaging studies, the temporal dynamics of cortical activity predicting the occurrence of voluntary or reflexive saccades in humans are largely unknown. Here, we examined electrophysiological activity preceding the onset of correct (i.e., voluntary) or error (i.e., reflexive) saccades in an oculomotor capture task. Participants executed saccades to lateralized visual targets while attempting to inhibit reflexive glances to abruptly appearing distracters. Since the visual display was identical for both types of saccades, different electrophysiological patterns preceding correct and error saccades could not be explained by low‐level perceptual differences. Compared to correct saccades electrophysiological activity preceding error saccades showed significant differences of the scalp electric field and of voltage amplitudes at posterior electrodes. In addition, though error saccades had significantly shorter latency than correct saccades a prolonged topographic configuration of electric potentials prior to error saccades was found ∼120–140 ms following target onset. In agreement with the known asymmetry in hemispheric dominance for spatial attention, distinct electrophysiological patterns were only found for leftward saccades. While error saccades were associated with stronger activity in the right Frontal Eye Field, correct saccades were preceded by stronger activity in the inferior parietal lobule. These findings suggest that selection of the saccade target in a conflicting situation is determined by early top‐down biases originating in frontal and parietal cortical regions critical for spatial attention and saccade programming. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
Chemotherapy‐induced structural changes in cerebral white matter and its correlation with impaired cognitive functioning in breast cancer patients
Authors: Deprez Sabine , Amant Frederic , Yigit Refika , Porke Kathleen , Verhoeven Judith , Stock Jan Van den , Smeets Ann , Christiaens Marie‐Rose , Leemans Alexander , Hecke Wim Van , Vandenberghe Joris , Vandenbulcke Mathieu , Sunaert Stefan
Published: May 2010

A subgroup of patients with breast cancer suffers from mild cognitive impairment after chemotherapy. To uncover the neural substrate of these mental complaints, we examined cerebral white matter (WM) integrity after chemotherapy using magnetic resonance diffusion tensor imaging (DTI) in combination with detailed cognitive assessment. Postchemotherapy breast cancer patients (n = 17) and matched healthy controls (n = 18) were recruited for DTI and neuropsychological testing, including the self‐report cognitive failure questionnaire (CFQ). Differences in DTI WM integrity parameters [fractional anisotropy (FA) and mean diffusivity (MD)] between patients and healthy controls were assessed using a voxel‐based two‐sample‐t‐test. In comparison with healthy controls, the patient group demonstrated decreased FA in frontal and temporal WM tracts and increased MD in frontal WM. These differences were also confirmed when comparing this patient group with an additional control group of nonchemotherapy‐treated breast cancer patients (n = 10). To address the heterogeneity observed in cognitive function after chemotherapy, we performed a voxel‐based correlation analysis between FA values and individual neuropsychological test scores. Significant correlations of FA with neuropsychological tests covering the domain of attention and processing/psychomotor speed were found in temporal and parietal WM tracts. Furthermore, CFQ scores correlated negatively in frontal and parietal WM. These studies show that chemotherapy seems to affect WM integrity and that parameters derived from DTI have the required sensitivity to quantify neural changes related to chemotherapy‐induced mild cognitive impairment. Hum Brain Mapp 32:480–493, 2011. © 2010 Wiley‐Liss, Inc.
An ex vivo imaging pipeline for producing high‐quality and high‐resolution diffusion‐weighted imaging datasets
Authors: Dyrby Tim B. , Baaré William F.C. , Alexander Daniel C. , Jelsing Jacob , Garde Ellen , Søgaard Lise V.
Published: May 2010

Diffusion tensor (DT) imaging and related multifiber reconstruction algorithms allow the study of in vivo microstructure and, by means of tractography, structural connectivity. Although reconstruction algorithms are promising imaging tools, high‐quality diffusion‐weighted imaging (DWI) datasets for verification and validation of postprocessing and analysis methods are lacking. Clinical in vivo DWI is limited by, for example, physiological noise and low signal‐to‐noise ratio. Here, we performed a series of DWI measurements on postmortem pig brains, which resemble the human brain in neuroanatomical complexity, to establish an ex vivo imaging pipeline for generating high‐quality DWI datasets. Perfusion fixation ensured that tissue characteristics were comparable to in vivo conditions. There were three main results: (i) heat conduction and unstable tissue mechanics accounted for time‐varying artefacts in the DWI dataset, which were present for up to 15 h after positioning brain tissue in the scanner; (ii) using fitted DT, q‐ball, and persistent angular structure magnetic resonance imaging algorithms, any b‐value between ∼2,000 and ∼8,000 s/mm2, with an optimal value around 4,000 s/mm2, allowed for consistent reconstruction of fiber directions; (iii) diffusivity measures in the postmortem brain tissue were stable over a 3‐year period. On the basis of these results, we established an optimized ex vivo pipeline for high‐quality and high‐resolution DWI. The pipeline produces DWI data sets with a high level of tissue structure detail showing for example two parallel horizontal rims in the cerebral cortex and multiple rims in the hippocampus. We conclude that high‐quality ex vivo DWI can be used to validate fiber reconstruction algorithms and to complement histological studies. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
The synthesis of optically active P‐heterocycles
Authors: Keglevich György , Dvorszki Judit , Ujj Viktória , Ludányi Krisztina
Published: May 2010

Optically active 1‐alkoxy‐ and 1‐amino‐3‐phospholene oxides were synthesized by the reaction of the corresponding 1‐chloro‐3‐phospholene oxides with (1R,2S,5R)‐(–)menthol and (S)‐(–)‐α‐phenylethylamine. The 3‐methyl‐3‐phospholene oxides were subjected to dichlorocyclopropanation under liquid–liquid phase transfer catalytic conditions to afford the 3‐phosphabicyclo[3.1.0]hexane 3‐oxides as a mixture of four diastereomers. Thermolysis of the menthyl‐phosphabicyclohexane oxides led to the corresponding 1,2‐dihydrophosphinine oxide as a diastereomeric mixture of two double‐bond isomers. As a result of additional steps, the dichlorocarbene addition reaction of the 1‐menthyl‐3,4‐dimethyl‐3‐phospholene oxide resulted in eventually, the formation of a 4‐dichloromethylene‐1,4‐dihydrophosphinine oxide. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:271–277, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20599
Structure–activity relationship of s‐triazoles and thiadiazoles as analgesics
Authors: Siwek Agata , Wujec Monika , Plech Tomasz , Kuśmierz Edyta , Jagiełło‐Wójtowicz Ewa , Chodkowska Anna
Published: May 2010

The influence of s‐triazoles (6–9) and thiadiazoles (10–11) on the central nervous system of mice in some behavioral tests was investigated. It was found that compounds (10) and (11) are the possible candidates for further development as analgesic agents. The correlation between the molecular descriptors and analgesic potential has been studied by using the pattern recognition methods: principal component analysis (PCA) and hierarchical cluster analysis (HCA). Our results, however, showed that the relationship between molecular descriptors and analgesic activity of s‐triazoles and thiadiazoles cannot be easily explained on the basis of PCA and HCA. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:256–264, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20605
Acute Liver Failure Is Associated With Elevated Liver Stiffness and Hepatic Stellate Cell Activation†
Authors: Dechêne Alexander , Sowa Jan-Peter , Gieseler Robert K. , Jochum Christoph , Bechmann Lars P. , El Fouly Amr , Schlattjan Martin , Saner Fuat , Baba Hideo A. , Paul Andreas , Dries Volker , Odenthal Margarethe , Gerken Guido , Friedman Scott L. , Canbay Ali
Published: May 2010

Acute liver failure (ALF) is associated with massive short-term cell death, whereas chronic liver injury is accompanied by continuous cell death. Hepatic stellate cells (HSCs) contribute to tissue repair and liver fibrosis in chronic liver injury, although their role in ALF remains unexplained. Twenty-nine patients (median age = 43 years, 17 females and 12 males) with ALF according to the Acute Liver Failure Study Group criteria were included. Upon the diagnosis of ALF and after 7 days, we determined liver stiffness (LS) with FibroScan, standard laboratory parameters, and serum levels of matrix metalloproteinase 1 (MMP-1), MMP-2, MMP-9, tissue inhibitor of metalloproteinases 1 (TIMP-1), TIMP-2, hyaluronic acid, and markers of overall cell death (M65) and apoptosis (M30). Stellate cell activation and progenitor response were analyzed immunohistochemically in biopsy samples of 12 patients with α-smooth muscle actin (α-SMA), keratin-17, and keratin-19 staining, respectively. Cell death markers (M30 level = 2243 ± 559.6 U/L, M65 level = 3732 ± 839.9 U/L) and fibrosis markers (TIMP-1 level = 629.9 ± 69.4 U/mL, MMP-2 level = 264 ± 32.5 U/mL, hyaluronic acid level = 438.5 ± 69.3 μg/mL) were significantly increased in patients versus healthy controls. This was paralleled by collagen deposition, elevated α-SMA expression, and higher LS (25.6 ± 3.0 kPa). ALF was associated with ductular progenitor proliferation.

Conclusion:

Our results demonstrate HSC activation and a progenitor response in ALF. Positive correlations between LS, the degree of liver cell damage, and the intensity of HSC activation suggest that fibrosis is a response to ALF in an attempt to repair damaged tissue.
On the analytical solution of the Bejan‐Khair equation arising in free convection in porous media
Authors: Bansod V.J. , Jadhav R.K.
Published: May 2010

This paper revisits the fundamental problem of free convection heat and mass transfer over a heated vertical surface embedded in a porous medium using analytical techniques. An integral procedure is applied to the boundary layer similar equation for the combined heat and mass transfer from a vertical surface in a porous medium. The analytical approximations have covered a wide range of governing parameters of the problem. The results for both Nusselt and Sherwood numbers agree well with numerical results published in the literature. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20297
The newborn infant: a missing stage in developmental psychology
Authors: Nagy Emese
Published: May 2010

Although neonatology, the study of the newborn, is well established in medical science, psychological research on the newborn is relatively scarce. Can we justify this period as a distinct stage of human development in Psychology? This introductory article considers the unique characteristics of the neonatal period, the impact of the transition to extrauterine life, including the impact of birth itself, and the stages of brain development that characterize this period. It presents evidence of an intentional, intersubjective neonate, and uses behavioural and neuroscientific evidence to argue that the neonate's early social preferences and responses indicate a unique, sensitive, experience‐expectant stage of development.

The authors of this issue agree in proposing that the newborn infant is prepared, evolutionarily and psychobiologically, to be born intersubjective. The notion of an intersubjective newborn infant, however, is virtually impossible to support without data and models from neuroscience, medicine, perinatology, physiology, ethology, evolutionary psychology and cognitive science. This issue is an attempt to bring scientists together from many of these fields to explore the unique characteristics of the first weeks of life. Copyright © 2010 John Wiley & Sons, Ltd.
What is it like to be a person who knows nothing? Defining the active intersubjective mind of a newborn human being
Authors: Trevarthen Colwyn
Published: May 2010

As thinking adults depend upon years of practical experience, reasoning about facts and causes, and language to sustain their knowledge, beliefs and memories, and to understand one another, it seems quite absurd to suggest that a newborn infant has intersubjective mental capacities. But detailed research on how neonatal selves coordinate the rhythms of their movements and senses, and how they engage in intimate and seductive precision with other persons' movements, sensing their purposes and feelings, gives evidence that it is so. The developmental and functional neuroscience of the human brain agrees. Indeed it seems that cultural intelligence itself is motivated at every stage by the kind of powers of innate intersubjective sympathy that an alert infant can show shortly after birth. We are born to generate shifting states of self‐awareness, to show them to other persons, and to provoke interest and affectionate responses from them. Thus starts a new psychology of the creativity and cooperative knowing and meaning in human communities. Copyright © 2010 John Wiley & Sons, Ltd.
MHC II lung cancer vaccines prime and boost tumor‐specific CD4+ T cells that cross‐react with multiple histologic subtypes of nonsmall cell lung cancer cells
Authors: Srivastava Minu K. , Bosch Jacobus J. , Wilson Ashley L. , Edelman Martin J. , Ostrand‐Rosenberg Suzanne
Published: May 2010

Nonsmall cell lung cancer (NSCLC) is the major cause of lung cancer‐related deaths in the United States. We are developing cell‐based vaccines as a new approach for the treatment of NSCLC. NSCLC is broadly divided into 3 histologic subtypes: adenocarcinoma, squamous cell carcinoma and large cell carcinoma. Since these subtypes are derived from the same progenitor cells, we hypothesized that they share common tumor antigens, and vaccines that induce immune reactivity against 1 subtype may also induce immunity against other subtypes. Our vaccine strategy has focused on activating tumor‐specific CD4+ T cells, a population of lymphocytes that facilitates the optimal activation of effector and memory cytotoxic CD8+ T cells. We now report that our NSCLC MHC II vaccines prepared from adeno, squamous or large cell carcinomas each activate CD4+ T cells that cross‐react with the other NSCLC subtypes and do not react with HLA‐DR‐matched normal lung fibroblasts or other HLA‐DR‐matched nonlung tumor cells. Using MHC II NSCLC vaccines expressing the DR1, DR4, DR7 or DR15 alleles, we also demonstrate that antigens shared among the different subtypes are presented by multiple HLA‐DR alleles. Therefore, MHC II NSCLC vaccines expressing a single HLA‐DR allele activate NSCLC‐specific CD4+ T cells that react with the 3 major classes of NSCLC, and the antigens recognized by the activated T cells are presented by several common HLA‐DR alleles, suggesting that the MHC II NSCLC vaccines are potential immunotherapeutics for a range of NSCLC patients.
Prognostic significance of regulatory T cells in tumor
Authors: Wilke Cailin Moira , Wu Ke , Zhao Ende , Wang Guobin , Zou Weiping
Published: May 2010

Since entering the immunological stage several decades ago, regulatory T cell biology has been realized as fundamentally important in the prevention of autoimmune conditions, induction of transplant tolerance and the immune response to cancer. The role of regulatory T cells in tumor immunobiology is still being elucidated. Currently, regulatory T cells are implicated in the dampening of antitumor T‐cell responses both through direct and indirect means. A number of investigators have demonstrated that regulatory T cell density and location may serve as independent prognostic factors in several types of cancer and are alternately detrimental or beneficial to patient survival. In this article, we will review the characteristics and functional phenotype of classical regulatory T cells, describe their distribution and quantification in tumor‐bearing hosts and summarize recent studies investigating the prognostic significance of regulatory T cell number and locality in various cancers.
Yield and water use efficiency of corn planted in one or two rows and applying furrow or drip tape irrigation systems in Ghazvin Province, Iran
Authors: Karimi Mohammad , Gomrokchi Afshin
Published: May 2010

This study investigated water use efficiency and yield in corn (SC 704) irrigated with drip (tape) and furrow irrigation systems in Ghazvin, Iran, in 2006. Four levels of irrigation including: 80, 100 and 120% of water requirement with drip irrigation (tape) and 100% water requirement with furrow irrigation as main plots and method of planting (one and two rows), as well as three levels of crop density including: 75 000, 90 000 and 105 000 (plants ha−1) as subplots were considered. The highest average grain yield was 12.9 t ha−1 while the treatment was drip irrigation at level of 120% water requirement in a two‐row planting pattern and crop density equal to 75 000 plants ha−1 (I3R2D1 treatment). The highest water use efficiency (WUE) was obtained in I3R2D1 treatment as 1.96 kg m−3, while the lowest was found in drip irrigation at a level of 80% water requirement in a two‐row planting pattern and crop density equal to 75 000 plants ha−1 (I1R2D1 treatment) as 0.82 kg m−3. Variance analysis of the grain yield data indicated that both planting pattern and interaction of planting pattern and crop density significantly affected the yields. Generally, the planting of one row resulted in significantly higher grain yields than the other planting pattern. Copyright © 2010 John Wiley & Sons, Ltd.
Cryogenic prototyping of chitosan scaffolds with controlled micro and macro architecture and their effect on in vivo neo‐vascularization and cellular infiltration
Authors: Lim Tze Chiun , Chian Kerm Sin , Leong Kah Fai
Published: May 2010

A major challenge in tissue engineering has been to develop scaffolds with controlled complex geometries, on both the macro‐ and micro‐scale. One group of techniques, using rapid prototyping (RP) processes, has the capability to produce complex three‐dimensional structures with good control over the size, geometry, and connectivity of the pores. In this article, a novel technique based on RP technology, that is, cryogenic prototyping (CP), that has the capability to fabricate scaffolds with controlled macro‐ and micro‐structures, is presented. Our in vivo studies showed that the micro architecture (i.e., both pore size and pore orientation) and macro structures of the CP scaffolds affect both cellular infiltration and neo‐vascularization. Full cellular infiltration and neo‐vascularization were observed after 28 days in scaffolds with micropore sizes of 90 μm. In addition, it was observed that channels (300 μm) created in scaffolds were effective at enhancing cellular infiltration and vascularization. Our results have demonstrated that CP is a viable method for fabricating scaffolds for a wide range of tissue engineering applications. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010
Fabrication of a biodegradable calcium polyphosphate/polyvinyl‐urethane carbonate composite for high load bearing osteosynthesis applications
Authors: Ramsay Scott D. , Pilliar Robert M. , Santerre J. Paul
Published: May 2010

The formation of biodegradable implants for use in osteosynthesis has been a major goal of biomaterials research for the past 2–3 decades. Self‐reinforced polylactide systems represent the most significant success of this research to date, however, with elastic constants up to 12–15 GPa at best, they fail to provide the initial stiffness required of devices for stabilizing fractures of major load‐bearing bones. Our research has investigated the use of calcium polyphosphate (CPP), an inorganic polymer in combination with polyvinyl‐urethane carbonate (PVUC) organic polymers for such applications. Initial studies indicated that composite samples formed as interpenetrating phase composites (IPC) exhibited suitable as‐made strength and stiffness, however, they displayed a rapid loss of properties when exposed to in vitro aging. An investigation to determine the mechanism of this accelerated in vitro degradation for the IPCs as well as to identify possible design changes to overcome this drawback was undertaken using a model IPC system. It was found that strong interfacial strength and minimal swelling of the PVUC are very important for obtaining and maintaining appropriate mechanical properties in vitro. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010.
Polymer coating of porcine decellularized and cross‐linked aortic grafts
Authors: Heidenhain Christoph , Weichert Wilko , Schmidmaier Gerhard , Wildemann Britt , Hein Moritz , Neuhaus Peter , Heise Michael
Published: May 2010

This article investigates a method of modifying and optimizing the biocompatibility of decellularized vascular bioimplants when treated with a specialized, drug eluting coating. For this purpose, we carried out aortic transplantations using a porcine model. Decellularized, cross‐linked aortic grafts were coated with poly(D,L‐lactide) (PDLLA). To this coating, we added the anticoagulant drug lepirudin which, following transplantation, would be linearly eluted. These aortic grafts are easily manipulated in surgery. It was shown that, as a result of the lepirudin‐eluting coating, the rate of thrombogenesis was reduced and the patency rate was significantly improved. However, lumen‐stenosing pseudointima developed in all of the transplants and was not effected by PDLLA coating. Furthermore, no evidence of recellularisation was documented. This trial demonstrates that polymer coating of decellularized tissue is possible. Neointimal hyperplasia and the absence of cellular repopulation mark the negative consequences of this concept. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010.
Plerixafor mobilization leads to a lower ratio of CD34+ cells to total nucleated cells which results in greater storage costs
Authors: Tanhehco Yvette C. , Adamski Jill , Sell Mary , Cunningham Kathleen , Eisenmann Christa , Magee Deborah , Stadtmauer Edward A. , O'Doherty Una
Published: May 2010

Background:

Plerixafor (Mozobil, AMD3100) with granulocyte‐colony stimulating factor (G‐CSF) mobilizes more CD34+ cells/kg compared to G‐CSF alone. Given that plerixafor enhances mobilization of multiple white blood cell lineages, we determined if more storage space is required for products collected from patients mobilized with plerixafor.

Methods:

A review of the medical records of 15 patients mobilized with chemotherapy and G‐CSF (control) and 14 patients mobilized with plerixafor plus G‐CSF (plerixafor) was performed. Data on demographics, baseline characteristics, CD34+ cells/kg, total nucleated cells, total mononuclear cells, total apheresis sessions, and total bags for storage were collected. Mean values were determined and compared using Student's t‐test.

Results:

We found that the proportion of CD34+ cells among total nucleated cells was less in the plerixafor group compared to the control group (P = 0.0427). More nucleated cells (10.7 × 1010 vs. 7.1 × 1010, P =0.0452) and mononuclear cells (9.7 × 1010 vs. 5.9 × 1010, P = 0.0059) were mobilized with plerixafor plus G‐CSF. However, there was no significant difference in CD34+ cells/kg, total CD34+ cells or the proportion of mononuclear cells among total nucleated cells between the two groups. More storage bags were required for the plerixafor group compared to the control group (15 vs. 9, P = 0.0299).

Conclusion:

Mobilization with plerixafor plus G‐CSF resulted in a smaller proportion of CD34+ cells collected and a greater number of storage bags. An increase in the number of bags required for stem cell storage may be logistically problematic and will also lead to increased costs for storage of stem cells. J. Clin. Apheresis 25:202–208, 2010. © 2010 Wiley‐Liss, Inc.
Computational studies on the mechanism and kinetics of Cl reaction with C2H5I
Authors: Jia Xiu‐Juan , Liu You‐Jun , Sun Jing‐Yu , Sun Hao , Wang Fang , Su Zhong‐Min , Pan Xiu‐Mei , Wang Rong‐Shun
Published: May 2010

The dual‐level direct kinetics method has been used to investigate the multichannel reactions of C2H5I + Cl. Three hydrogen abstraction channels and one displacement process are found for the title reaction. The calculation indicates that the hydrogen abstraction from CH2 group is the dominant reaction channel, and the displacement process may be negligible because of the high barrier. The rate constants for individual reaction channels are calculated by the improved canonical variational transition‐state theory with small‐curvature tunneling correction over the temperature range of 220–1500 K. Our results show that the tunneling correction plays an important role in the rate constant calculation in the low‐temperature range. Agreement between the calculated and experimental data available is good. The Arrhenius expression k(T) = 2.33 × 10−16 T1.83 exp(−185.01/T) over a wide temperature range is obtained. Furthermore, the kinetic isotope effects for the reaction C2H5I + Cl are estimated so as to provide theoretical estimation for future laboratory investigation. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Implementation of an algorithm based on the Runge‐Kutta‐Fehlberg technique and the potential energy as a reaction coordinate to locate intrinsic reaction paths
Authors: Aguilar‐Mogas Antoni , Giménez Xavier , Bofill Josep Maria
Published: May 2010

The intrinsic reaction coordinate (IRC) curve is used widely as a representation of the Reaction Path and can be parameterized taking the potential energy as a reaction coordinate (Aguilar‐Mogas et al., J Chem Phys 2008, 128, 104102). Taking this parameterization and its variational nature, an algorithm is proposed that permits to locate this type of curve joining two points from an arbitrary curve that joints the same initial and final points. The initial and final points are minima of the potential energy surface associated with the geometry of reactants and products of the reaction whose mechanism is under study. The arbitrary curves are moved toward the IRC curve by a Runge‐Kutta‐Fehlberg technique. This technique integrates a set of differential equations resulting from the minimization until value zero of the line integral over the Weierstrass E‐function. The Weierstrass E‐function is related with the second variation in the theory of calculus of variations. The algorithm has been proved in real chemical systems. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
SKATE: A docking program that decouples systematic sampling from scoring
Authors: Feng Jianwen A. , Marshall Garland R.
Published: May 2010

SKATE is a docking prototype that decouples systematic sampling from scoring. This novel approach removes any interdependence between sampling and scoring functions to achieve better sampling and, thus, improves docking accuracy. SKATE systematically samples a ligand's conformational, rotational and translational degrees of freedom, as constrained by a receptor pocket, to find sterically allowed poses. Efficient systematic sampling is achieved by pruning the combinatorial tree using aggregate assembly, discriminant analysis, adaptive sampling, radial sampling, and clustering. Because systematic sampling is decoupled from scoring, the poses generated by SKATE can be ranked by any published, or in‐house, scoring function. To test the performance of SKATE, ligands from the Asetex/CDCC set, the Surflex set, and the Vertex set, a total of 266 complexes, were redocked to their respective receptors. The results show that SKATE was able to sample poses within 2 Å RMSD of the native structure for 98, 95, and 98% of the cases in the Astex/CDCC, Surflex, and Vertex sets, respectively. Cross‐docking accuracy of SKATE was also assessed by docking 10 ligands to thymidine kinase and 73 ligands to cyclin‐dependent kinase. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Modeling environmental effects on charge density distributions in polar organometallics: Validation of embedded cluster models for the methyl lithium crystal
Authors: Götz Kathrin , Meier Florian , Gatti Carlo , Burow Asbjörn M. , Sierka Marek , Sauer Joachim , Kaupp Martin
Published: May 2010

The charge density and its Laplacian at the LiC and CH bond critical points and other features of the electron density distribution of the methyl lithium crystal have been compared by density functional methods for (i) the isolated (LiCH3)4tetramer or larger clusters, (ii) for quantum mechanically treated clusters in polarizable continuum model (PCM) surroundings, (iii) for clusters augmented by the periodic electrostatic embedded cluster model (PEECM), and for (iv) the periodic crystal. Comparisons with identical functional and basis sets indicate that both PCM and PEECM embedding of only a tetramer did not fully account for the environmental effect. In contrast, embedding of a full unit cell gave results that were essentially converged to the periodic crystal data. Effects of basis set and exchange correlation functional on the QTAIM bond descriptors are of a comparable order of magnitude as the crystal environmental effects. In this context, embedded cluster computations provide distinct advantages over explicit solid‐state calculations with respect to their freedom of the choice of computational and theoretical level. This is demonstrated by embedded MP2 calculations. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Serum prolidase enzyme activity and its relation to histopathological findings in patients with non‐alcoholic steatohepatitis
Authors: Horoz Mehmet , Aslan Mehmet , Bolukbas Fusun F. , Bolukbas Cengiz , Nazligul Yasar , Celik Hakim , Aksoy Nurten
Published: May 2010

The aim of this study was to investigate serum prolidase enzyme activity and to find out its association with liver biopsy specimens' histopathological findings in patients with nonalcoholic steatohepatitis (NASH), which may progress to liver fibrosis and cirrhosis. Thirty‐six patients with biopsy‐proven NASH and 29 healthy controls were enrolled. Serum prolidase enzyme activity was measured spectrophotometrically. Serum prolidase enzyme activity was significantly higher in patients with NASH thancontrols (P=0.016). A significant correlation was observed between serum prolidase enzyme activity and fibrosis score in patients with NASH (r=0.661,P<0.001). Serum prolidase activity seems to be correlated with the level of fibrosis. Monitoring serum prolidase activity may be a useful adjunctive tool in predicting liver fibrosis, especially in the absence of advanced fibrosis and other conditions, which may affect the interpretation of prolidase activity. J. Clin. Lab. Anal. 24:207–211, 2010. © 2009 Wiley‐Liss, Inc.
Exogenous interferences with Jaffe creatinine assays: addition of sodium dodecyl sulfate to reagent eliminates bilirubin and total protein interference with Jaffe methods
Authors: Srisawasdi P. , Chaichanajarernkul U. , Teerakanjana N. , Vanavanan S. , Kroll M.H.
Published: May 2010

Background: The study evaluated the impact of interferences on the analytical specificity of three commercial and commonly used creatinine methods (two Jaffe and one enzymatic).

Methods: Manufacturer creatinine methods plus modified methods were tested with the following interferences: spiking serum with bilirubin, albumin, glucose, hemoglobin and lipid, and patient sera with maximum concentrations of bilirubin, 1,090 µmol/l and protein, 117.8 g/l.

Results: Hemoglobin, 7.5 g/l and lipaemic with triglyceride concentration of 6.27 mmol/l, did not interfere with all assays. Glucose >33.3 mmol/l increased creatinine recovery for Dimension method. Samples spiked with bilirubin imparted a negative bias for Dimension and Architect methods but imparted a positive bias for Vitros assay. However, using patient sera, negative bias with bilirubin was found for all methods, from which Architect method gave the highest effect (R2=0.861), followed by Vitros (R2=0.239) and Dimension (R2=0.163). Protein provided the positive bias for all creatinine measurements that increased with increasing concentration (R2 ranging from 0.104 to 0.182, P<0.0001). Addition of sodium dodecyl sulfate (SDS) in alkaline‐picrate reagent reduced the effect of bilirubin and protein for kinetic Jaffe method. Although adding potassium ferricyanide was well effective for eliminating negative interference of bilirubin, it was prone to interference from protein.

Conclusions: Endogenous interferences continue to plague creatinine accuracy measurement in both Jaffe and enzymatic methods, and consequentially the estimated glomerular filtration rate. The addition of SDS to the alkaline‐pirate reagent was shown to be effective in reducing bilirubin and protein interferences. J. Clin. Lab. Anal. 24:123–133, 2010. © 2009 Wiley‐Liss, Inc.
Evaluation of the poly(ADP‐ribose) polymerase‐1 gene variants in Alzheimer's disease
Authors: Liu Hsin‐Ping , Lin Wei‐Yong , Wu Bor‐Tsang , Liu Shu‐Hsiang , Wang Wen‐Fu , Tsai Chon‐Haw , Lee Chun‐Cheng , Tsai Fuu‐Jen
Published: May 2010

Amyloid peptide is thought to play a critical role in neuronal death in Alzheimer's disease (AD), most likely through oxidative stress. Free radical‐related injury leads to DNA breaks, which subsequently activates the repair enzyme poly(ADP‐ribose) polymerase‐1 (PARP‐1). In this study, the relationship between genetic variants situated at the PARP‐1 gene and AD development was investigated. We performed a case and control study from a Taiwanese population enrolled 120 AD patients and 111 healthy controls by using a polymerase chain reaction restriction fragment length polymorphism approach for two PARP‐1 exonic polymorphisms, 414C/T (rs1805404) and 2456T/C (rs1136410), corresponding to protein residues at positions 81Asp/Asp and762Val/Ala. There were no significant differences in allele or genotype frequencies for either PARP‐1 gene variant between the case and control groups; however, upon analysis of the haplotype distribution, four haplotypes (Hts) were identified. We found that the distributions of Ht3‐TT and Ht4‐CC were significantly associated with an increased risk of AD (P<0.0001), whereas the Ht1‐TC haplotype showed a protective effect for cases compared with the control group (P<0.05). These results reveal that the PARP‐1 gene is highly associated with AD susceptibility and might contribute to a critical mechanism that mediates cell survival or death as a response to cytotoxic stress. J. Clin. Lab. Anal. 24:182–186, 2010. © 2010 Wiley‐Liss, Inc.
Application of monoclonal antibodies to measure metabolism of an anti‐trypanosomal compound in vitro and in vivo
Authors: Goldsmith Rachel Beaulieu , Gray Danny R. , Yan Zhixia , Generaux Claudia N. , Tidwell Richard R. , Reisner Howard M.
Published: May 2010

Human African trypanosomiasis (HAT), also called African sleeping sickness, is a neglected tropical parasitic disease indigenous to sub‐Saharan Africa. Diamidine compounds, including pentamidine and CPD‐0801, are potent anti‐trypanosomal molecules. The latter is a potential drug in the development at the UNC based Consortium for Parasitic Drug Development. An orally bioavailable prodrug of CPD‐0801, DB868, is metabolized primarily in the liver to the active form. A monoclonal antibody developed against a pentamidine derivative has shown significant reactivity with CPD‐0801 (EC50 65.1 nM), but not with the prodrug (EC50>18,000 nM). An inhibitory enzyme‐linked immunosorbent assay (IELISA) has been used to quantitatively monitor prodrug metabolism by detecting the production of the active compound over time in a sandwich culture rat hepatocyte system and in rats. These results were compared with the results of the standard LC/MS/MS assay. Spearman coefficients of 0.96 and 0.933 (in vitro and in vivo, respectively) indicate a high correlation between these two measurement methods. This novel IELISA provides a facile, inexpensive, and accurate method for drug detection that may aide in elucidating the mechanisms of action and toxicity of existing and future diamidine compounds. J. Clin. Lab. Anal. 24:187–194, 2010. © 2010 Wiley‐Liss, Inc.
Microvasculature of the buffalo (Bubalus bubalis) choroid plexuses: Structural, histochemical, and immunocytochemical study
Authors: Scala Gaetano , Corona Mario , Langella Emilia , Maruccio Lucianna
Published: May 2010

The choroid plexuses (CPs) in mammals produce the cerebrospinal fluid (CSF). In the literature, the morphology of CPs and the process that regulates the production of CSF are virtually nonexistent for domestic ruminants. Thus this study has two aims: 1. to investigate the morpho‐structure of the buffalo CP microvasculature utilizing light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques, and 2. to investigate the relationship between the blood vessels and both the elongated cells and the cells with multiple protrusions located in the CPs. SEM and TEM analyses of the CPs from buffalo brain showed morphological and structural features similar those reported in other mammalian species. Moreover the blood microvasculature is the major component responsible for the formation of the CSF, secreted by the encephalic CPs. In addition the chemical composition of this fluid depends on several morpho‐functional characteristics of the vascularization of the CPs. These characteristics are as follows: two shapes of the vascular organization: lamina‐like and ovoid‐like elongated cells of the CPs, which connect the ventricular cavities to the blood capillaries; and the CP capillaries have diverse forms. In the present study the employment of NADPHd and NOS I was taken as indirect evidence for the presence of NO for investigation their specific role in CPs. Then NOS I immunoreactivity is found in the walls of CP blood vessels demonstrating indirectly the presence of NO with a vaso‐dilatatory and autoregulation function of vascular tone by cholinergic nerve stimulation of blood vessel smooth muscle. Microsc. Res. Tech. 74:67‐75, 2011. © 2010 Wiley‐Liss, Inc.
Secretory profile of metapleural gland cells of the leaf‐cutting ant Acromyrmex coronatus (Formicidae: Attini)
Authors: Vieira Alexsandro Santana , Bueno Odair Correa , Camargo‐Mathias Maria Izabel
Published: May 2010

Ants present a pair of metapleural glands located at the posterolateral end of the thorax. Because of its importance in the social organization of ants, the present study was aimed at describing the morphophysiology of this gland in three worker castes of Acromyrmex coronatus, focused on secretory activity using histological and histochemical techniques. Our findings revealed that the secretory and the storage portions of this gland are connected by extracytoplasmic portion of canaliculi that drain the secretion from each secretory cell to the collecting chamber. This secretion contains glycoproteins. In minor workers, the secretion contains higher levels of polysaccharides when compared to that of major workers, supporting the role of the metapleural gland in the maintenance of the fungus garden. The nucleus as well as cytoplasm of secretory cells were strongly positive for RNA indicating that these cells are active in the synthesis of proteins and lipids, compounds found in the final secretion. The variant of the CEC revealed that the secretory activity of the entire gland is synchronous, as all cells exhibit the result. Microsc. Res. Tech. 74:76‐83, 2011. © 2010 Wiley‐Liss, Inc.