bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical and morphological properties of lyocell blends: Comparison with lyocell nanocomposites (I)
Authors: Chang Jin‐Hae , Nam Si Wook , Jang Seo‐Won
Published: August 2007

The mechanical properties and morphologies of polyblends of lyocell with three different fillers are compared. Poly(vinyl alcohol) (PVA), poly(vinyl alcohol‐co‐ethylene) (EVOH), and poly(acrylic acid‐co‐maleic acid) (PAM) were used as fillers in blends with lyocell produced through solution blending. The variations of their properties with polymer matrix filler content are discussed. The ultimate tensile strength of the PVA/lyocell blend is highest for a blend lyocell content of 30 wt %, and decreases as the lyocell content is increased up to 40 wt %. The ultimate tensile strengths of the EVOH/lyocell and PAM/lyocell blends are highest for a lyocell loading of 20 wt %, and decrease with the increasing filler content. The variations in the initial moduli of the blends with filler content are similar. Of the three blend systems, the blends with PVA exhibit the best tensile properties. Lyocell/organoclay hybrid films were prepared by the solution intercalation method, using dodecyltriphenylphosphonium–Mica (C12PPh‐ Mica) as the organoclay. The variation of the mechanical tensile properties of the hybrids with the matrix polymer organoclay content was examined. These properties were found to be optimal for an organoclay content of up to 5 wt %. Even polymers with low organoclay contents exhibited better mechanical properties than pure lyocell. The addition of organoclay to lyocell to produce nanocomposite films was found to be less effective in improving its ultimate tensile strength than blending lyocell with the polymers. However, the initial moduli of the nanocomposites were found to be higher than those of the polyblend films. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Preparation of poly(acrylic acid‐co‐acrylamide)/kaolin and release kinetics of urea from it
Authors: Liang Rui , Liu Mingzhu
Published: August 2007

A series of poly(acrylic acid‐co‐acrylamide)/kaolin [poly(AA‐co‐Am)/kaolin] composites were prepared by aqueous solution copolymerization of partially neutralized acrylic acid and acrylamide in the presence of kaolin nanopowder, which was synthesized to act as a release carrier of urea fertilizer. The superabsorbent composite was swollen in aqueous solution of urea to load urea, and the effect of urea concentration on the swelling was investigated. Furthermore, the effects of the contents of crosslinker, kaolin, and acrylamide, the neutralization degree of acrylic acid, and temperature, pH, and ionic strength of release medium on water absorbency and diffusion coefficient of urea release from poly(AA‐co‐Am)/kaolin were studied systematically. It was found that urea loading percentage could be adjusted by urea concentration of swelling medium, and urea diffusion coefficient could be regulated through the contents of crosslinker, kaolin, and acrylamide, and the neutralization degree of acrylic acid. Additionally, temperature and ionic strength of release medium may also affect the urea release process. The conclusions obtained could provide theoretical basis for urea diffusion behavior in superabsorbent used in agriculture. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Medium‐term horizon volatility forecasting: A comparative study
Authors: Hawkes Richard , Date Paresh
Published: August 2007

In this paper, volatility is estimated and then forecast using unobserved components‐realized volatility (UC‐RV) models as well as constant volatility and GARCH models. With the objective of forecasting medium‐term horizon volatility, various prediction methods are employed: multi‐period prediction, variable sampling intervals and scaling. The optimality of these methods is compared in terms of their forecasting performance. To this end, several UC‐RV models are presented and then calibrated using the Kalman filter. Validation is based on the standard errors on the parameter estimates and a comparison with other models employed in the literature such as constant volatility and GARCH models. Although we have volatility forecasting for the computation of Value‐at‐Risk in mind the methodology presented has wider applications. This investigation into practical volatility forecasting complements the substantial body of work on realized volatility‐based modelling in business. Copyright © 2007 John Wiley & Sons, Ltd.
Male pregnancy in seahorses and pipefish: beyond the mammalian model
Authors: Stölting Kai N. , Wilson Anthony B.
Published: August 2007

Pregnancy has been traditionally defined as the period during which developing embryos are incubated in the body after egg–sperm union. Despite strong similarities between viviparity in mammals and other vertebrate groups, researchers have historically been reluctant to use the term pregnancy for non‐mammals in recognition of the highly developed form of viviparity in eutherians. Syngnathid fishes (seahorses and pipefishes) have a unique reproductive system, where the male incubates developing embryos in a specialized brooding structure in which they are aerated, osmoregulated, protected and likely provisioned during their development. Recent insights into physiological, morphological and genetic changes associated with syngnathid reproduction provide compelling evidence that male incubation in these species is a highly specialized form of reproduction akin to other forms of viviparity. Here, we review these recent advances, highlighting similarities and differences between seahorse and mammalian pregnancy. Understanding the changes associated with the parallel evolution of male pregnancy in the two major syngnathid lineages will help to identify key innovations that facilitated the development of this unique form of reproduction and, through comparison with other forms of live bearing, may allow the identification of a common set of characteristics shared by all viviparous organisms. BioEssays 29:884–896, 2007. © 2007 Wiley Periodicals, Inc.
Nutrient deprivation induces autophagy as well as apoptosis in Chinese hamster ovary cell culture
Authors: Hwang Sun Ok , Lee Gyun Min
Published: August 2007

During Chinese hamster ovary (CHO) cell culture for foreign protein production, cells are subjected to programmed cell death (PCD). A rapid death at the end of batch culture is accelerated by nutrient starvation. In this study, type II PCD, autophagy, as well as type I PCD, apoptosis, was found to take place in two antibody‐producing CHO cell lines, Ab1 and Ab2, toward the end of batch culture when glucose and glutamine were limiting. The evidence of autophagy was observed from the accumulation of a common autophagic marker, a 16 kDa form of LC3‐II during batch culture. Moreover, a significant percentage of the total cells (80% of Ab1 cells and 86% of Ab2 cells) showed autophagic vacuoles containing cytoplasmic material by transmission electron microscopy. An increased level of PARP cleavage and chromosomal DNA fragmentation supported that starvation‐induced apoptosis also occurred simultaneously with autophagy. Biotechnol. Bioeng. 2008;99: 678–685. © 2007 Wiley Periodicals, Inc.
Fluorescence‐based soft‐sensor for monitoring β‐lactoglobulin and α‐lactalbumin solubility during thermal aggregation
Authors: Elshereef Rand , Budman Hector , Moresoli Christine , Legge Raymond L.
Published: August 2007

A soft‐sensor for monitoring solubility of native‐like α‐lactalbumin (α‐LA) and β‐lactoglobulin (β‐LG) and their aggregation behavior following heat treatment of mixtures under different treatment conditions was developed using fluorescence spectroscopy data regressed with a multivariate Partial Least Squares (PLS) regression algorithm. PLS regression was used to correlate the concentrations of α‐LA and β‐LG to the fluorescence spectra obtained for their mixtures. Data for the calibration and validation of the soft sensor was derived from fluorescence spectra. The process of thermal induced aggregation of β‐LG and α‐LA protein in mixtures, which involves the disappearance of native‐like proteins, was studied under various treatment conditions including different temperatures, pH, total initial protein concentration and proportions of α‐LA and β‐LG. It was demonstrated that the multivariate regression models used could effectively deconvolute multi‐wavelength fluorescence spectra collected under a variety of process conditions and provide a fairly accurate quantification of respective native‐like proteins despite the significant overlapping between their emission profiles. It was also demonstrated that a PLS model can be used as a black‐box prediction tool for estimating protein aggregation when combined with simple mass balances. Bioeng. 2008;99: 567–577. © 2007 Wiley Periodicals, Inc.
A One‐Pot Synthesis of (E)‐Disubstituted Alkenes by a Bimetallic [Rh–Pd]‐Catalyzed Hydrosilylation/Hiyama Cross‐Coupling Sequence
Authors: Thiot Carine , Schmutz Marc , Wagner Alain , Mioskowski Charles
Published: August 2007

A bimetallic [Rh–Pd] catalyst was prepared by soaking into an iodide ionic gel an equimolar solution of [RhCl(PPh3)3] and Pd(OAc)2 in CH2Cl2. Its catalytic activity was evaluated by rhodium‐catalyzed hydrosilylation (H), palladium‐catalyzed Hiyama coupling (C), and in the one‐pot hydrosilylation/Hiyama coupling sequence (H/C). It was found that the homogeneous combination [RhCl(PPh3)3]/NaI was a superior system compared to the polyionic mono‐ and bimetallic rhodium catalysts in the hydrosilylation of terminal alkynes. Interestingly, the most effective catalyst in terms of stereo‐ and chemoselectivities was observed to be the bimetallic ionic gel [Rh–Pd] in the one‐pot process leading to (E)‐alkenes with good yields. The remarkable stereocontrol is ascribed to a beneficial Pd‐catalyzed isomerization from the mixture of stereoisomeric vinylsilanes obtained in the initial hydrosilylation step into the more stable (E)‐adduct. The [Rh–Pd] heterogeneous catalyst also showed a higher chemoselectivity than the homogeneous catalytic combination, and no detrimental formation of Sonogashira side product was observed due to an ionic‐gel‐mediated kinetic modulation. To illustrate its scope and limitations, the described one‐pot bimetallic catalytic sequence was extended to functionalized terminal alkynes and various iodide substrates. Conjugated systems, such as hydroxycinnamaldehyde, dienes, and trienes, were synthesized in good overall yields. To avoid deactivation of the Rh species, N‐heterocyclic iodides had to be added sequentially after completion of hydrosilylation.
Thoughts About the Abnormalities in the Electrocardiogram of Patients with Acute Myocardial Infarction with Emphasis on a more Accurate Method of Interpreting ST‐segment Displacement: Part I
Authors: Willis Hurst J.
Published: August 2007

The QRS, S‐T, and T wave abnormalities produced by the usual myocardial infarction are discussed in Part I of this manuscript.

The recent guidelines supplied by the ACC/AHA Practice Guidelines divide primary S‐T segment displacement into S‐T segment elevated myocardial infarction (STEMI) and non S‐T segment elevated myocardial infarction (NSTEMI). Accordingly, the electrophysiologic mechanisms responsible for epicardial and subendocardial injury that produce the S‐T segment abnormalities are discussed in this manuscript. In this regard, the author suggests that the Grant method of interpreting the 12 lead electrocardiogram, which uses basic principles and vector concepts, is a more accurate method of identifying epicardial injury and subendocardial injury than memorizing the rules provided by the guidelines. An electrocardiogram is shown to illustrate this point. In Addition, the author expresses his personal view that labeling an electrocardiogram as NSTEMI but not stating what is actually present in the tracing is a cumbersome method of communication. The author believes it is better communication to state what is present rather than to state what is not present. At best, the result of both assessments should be stated in the interpretation.

Part II of the manuscript is devoted to a discussion as to why treatment with thrombolytic or percutaneous coronary intervention is more effective in patients whose electrocardiograms reveal epicardial injury than it is in patients whose electrocardiograms reveal subendocardial injury or no injury. Copyright © 2007 Wiley Periodicals, Inc.
The influence of socio‐demographic and illness variables on quality of life in acute psychiatric inpatients
Authors: Hodgson Z. G. , Pattison C. , Bostock L. , Murphy T. , Stewart M. E.
Published: August 2007

The mental‐health literature highlights the importance of improved quality of life as an explicit goal of the mental‐health service. Recent work indicates that assessment of subjective quality of life can be feasible and meaningful in individuals with psychiatric disorders. Although a number of studies have examined the influence of demographic variables on subjective quality of life in individuals with psychiatric disorders, there remains a paucity of studies that have made comparisons between diagnoses in inpatient populations. We used the WHOQOL‐BREF to examine the influence of different psychiatric diagnoses on quality of life and investigated whether the relationship between demographic variables and quality of life was the same across diagnoses. We found that the relationship between demographic and illness variables was complex, with inconsistent effects across WHOQOL‐BREF domains. Certain domains of the WHOQOL‐BREF were more sensitive to the influence of psychiatric diagnosis than others. Copyright © 2007 John Wiley & Sons, Ltd.
Anemia and Interleukin‐6 Are Associated with Faster Progression to End‐Stage Renal Disease
Authors: Neves Pedro L. , Morgado Elsa , Baptista Alexandre , Sampaio Sandra , Faísca Marília , Silva Ana P. , Santos João P.
Published: August 2007

BACKGROUND

Various classical risk factors are associated with the progression of chronic kidney disease (CKD) and, recently, novel risk factors have been identified. The aim of this study was to identify factors associated with the risk of end‐stage renal disease (ESRD) in a population of patients with CKD stages 4 and 5.

METHODS

We prospectively followed renal patients at our clinic (mean glomerular filtration rate [GFR] of 16.9 mL/min) for an average of 12.4 months. The end point was initiation of dialysis. For comparisons between groups, we used Student's t‐ and χ2 tests. Using the Cox proportional hazard model, we regressed several independent variables on time to dialysis. We also evaluated the influence of IL‐6 on the progression of CKD, using the Kaplan–Meier method.

RESULTS

Ninety‐five patients (54 men; mean age, 69.4 years) participated in the study. A greater proportion of those who began dialysis were male (p = 0.003). Their GFR (p = 0.0001), hemoglobin (p = 0.024), and the albumin (p = 0.034) levels were lower and their IL‐6 was higher (p = 0.002) than those who did not begin dialysis. We also found that male sex (p = 0.001), hypertension (p = 0.043), lower GFR level (p = 0.018), lower hemoglobin level (p = 0.039), and higher IL‐6 level (p = 0.0001) predicted faster progression to ESRD. Patients whose IL‐6 levels were in the upper quartiles had lower kidney survival after 12 months (log rank = 35.1, p = 0.0001).

CONCLUSION

In our population, anemia and interleukin‐6 were associated with faster progression to ESRD.
Rapid acquisition of operant conditioning in 5‐day‐old rat pups: A new technique articulating suckling‐related motor activity and milk reinforcement
Authors: Arias Carlos , Spear Norman E. , Molina Juan Carlos , Molina Agustin , Molina Juan Carlos
Published: August 2007

Newborn rats are capable of obtaining milk by attaching to a surrogate nipple. During this procedure pups show a gradual increase in head and forelimb movements oriented towards the artificial device that are similar to those observed during nipple attachment. In the present study the probability of execution of these behaviors was analyzed as a function of their contingency with intraoral milk infusion using brief training procedures (15 min). Five‐day‐old pups were positioned in a smooth surface having access to a touch‐sensitive sensor. Physical contact with the sensor activated an infusion pump which served to deliver intraoral milk reinforcement (Paired group). Yoked controls received the reinforcer when Paired neonates touched the sensor. Paired pups trained under a continuous reinforcement schedule emitted significantly more responses than Yoked controls following two (Experiment 1) or one training session (Experiment 2). These differences were also observed during an extinction session conducted immediately after training. The level of maternal deprivation before training (3 or 6 hr) or the volume of milk delivered (1.0 or 1.5 µl per pulse) did not affect acquisition or extinction performances. In addition, it was observed that the rate of responding of Paired pups during the early phase of the extinction session significantly predicted subsequent levels of acceptance of the reinforcer. These results indicate that the frequency of suckling‐related behaviors can be rapidly modified by means of associative operant processes. The operant procedure here described represents an alternative tool for the ontogenetic analysis of self‐administration or behavior processes of seeking. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 576‐588, 2007.
Decline in age‐dependent, MK801‐induced injury coincides with developmental switch in parvalbumin expression: Cingulate and retrosplenial cortex
Authors: Lema Tomé Carla M. , Miller Ryan , Bauer Clayton , Nottingham Charles , Smith Chelsey , Blackstone Kaitlin , Brown Lauren , Bryan Rachael , Leigh Adam , Brady Megan , Busch Jamie , Turner Christopher P.
Published: August 2007

Age‐dependent, MK801‐induced, activated caspase‐3 expression in the postnatal brain is generally not observed in neurons expressing calcium‐binding proteins (CaBPs), suggesting that apoptosis and calcium buffering are inversely related. In regions such as the cingulate and retrosplenial cortex, injury peaks at postnatal Day 7 (P7) and rapidly diminishes thereafter, whereas expression of calbindin (CB) and calretinin (CR) was relatively low from P0 to P7 and steadily increased from P7 to P14. At ages thereafter, CB and CR expression either remained stable then declined or rapidly declined. Parvalbumin (PV) was generally low‐absent prior to P7 but expression dramatically increased from P10 onwards, peaking at P21. These studies suggest calcium entry (through N‐methyl‐D‐aspartate receptor (NMDARs)) and buffering (by CaBPs) are integral to normal CNS maturation. Because schizophrenia is associated with glutamate hypo‐function, developmental injury, and aberrant CaBP expression, our data indicate that this postnatal brain injury model may offer important insights into the nature of this disorder. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 606‐618, 2007.
The influence of parent–infant cosleeping, nursing, and childcare on cortisol and SIgA immunity in a sample of british children
Authors: Waynforth David
Published: August 2007

Substantial variation in childcare arrangements exists both within and between populations. Research has suggested negative stress‐related outcomes for children who regularly attend daycare facilities. In the present study, 122 cortisol and 94 secretory immunoglobulin A (SIgA) samples from 32 British children aged between 3 and 8 were analyzed using multilevel modeling to assess effects of daycare attendance and other childcare‐related variables on children's stress and SIgA immune function. Parents' reports of children's aggression and family discord within 2 hr of saliva collection were associated with elevated cortisol levels in children. With these acute stressors statistically controlled, retrospective data on parent–child cosleeping showed that children who had coslept in their parent(s) room had lower cortisol levels, as did children who had attended less daycare in the first 4 years of life. The parenting‐related variables did not predict SIgA immunity. The results are discussed in the context of theories of parenting strategies. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 640‐648, 2007.
Dystroglycan protein distribution coincides with basement membranes and muscle differentiation during mouse embryogenesis
Authors: Anderson Claire , Winder Steven J. , Borycki Anne‐Gaëlle
Published: August 2007

Using immunohistochemistry, we have examined β‐Dystroglycan protein distribution in the mouse embryo at embryonic stages E9.5 to E11.5. Our data show that Dystroglycan expression correlates with basement membranes in many tissues, such as the notochord, neural tube, promesonephros, and myotome. In the myotome, we describe the timing of Dystroglycan protein re‐distribution at the surface of myogenic precursor cells as basement membrane assembles into a continuous sheet. We also report on non‐basement‐membrane‐associated Dystroglycan expression in the floor plate and the myocardium. This distribution often corresponds to sites of expression previously reported in adults, suggesting that Dystroglycan is continuously produced during development. Developmental Dynamics 236:2627–2635, 2007. © 2007 Wiley‐Liss, Inc.
Mice lacking the Obox6 homeobox gene undergo normal early embryonic development and are fertile
Authors: Cheng Wei‐Cheng , Hsieh‐Li Hsiu Mei , Yeh Yu‐Jung , Li Hung
Published: August 2007

Obox6 is a member of the Obox (oocyte‐specific homeobox) gene family. The Obox6 gene was isolated from the mouse two‐cell embryonic cDNA library. Using reverse transcriptase‐polymerase chain reaction analysis, we found Obox6 is expressed exclusively in early embryonic stages and exhibits an elevated expression from the two‐cell stage to the morula stage. The gene is thought to be involved in early embryogenesis. To study the function of Obox6 in early embryogenesis, we generated Obox6 mutant mice using a gene targeting strategy. Obox6 mutant mice with genetic background of C57BL/6J inbred were born according to Mendelian rules without apparent defects. The mutant mice grew without morphological abnormalities and with normal fertility. The lack of an obvious phenotype in Obox6‐null mice and altered RNA levels of some Obox genes raise the possibility that other members of the Obox gene family can compensate for Obox6 function during embryogenesis. Developmental Dynamics 236:2636–2642, 2007. © 2007 Wiley‐Liss, Inc.
Identification of Lmo1 as part of a Hox‐dependent regulatory network for hindbrain patterning
Authors: Matis Christelle , Oury Franck , Remacle Sophie , Lampe Xavier , Gofflot Françoise , Picard Jacques J. , Rijli Filippo M. , Rezsohazy René
Published: August 2007

The embryonic functions of Hox proteins have been extensively investigated in several animal phyla. These transcription factors act as selectors of developmental programmes, to govern the morphogenesis of multiple structures and organs. However, despite the variety of morphogenetic processes Hox proteins are involved in, only a limited set of their target genes has been identified so far. To find additional targets, we used a strategy based upon the simultaneous overexpression of Hoxa2 and its cofactors Pbx1 and Prep in a cellular model. Among genes whose expression was upregulated, we identified LMO1, which codes for an intertwining LIM‐only factor involved in protein–DNA oligomeric complexes. By analysing its expression in Hox knockout mice, we show that Lmo1 is differentially regulated by Hoxa2 and Hoxb2, in specific columns of hindbrain neuronal progenitors. These results suggest that Lmo1 takes part in a Hox paralogue 2–dependent network regulating anteroposterior and dorsoventral hindbrain patterning. Developmental Dynamics 236:2675–2684, 2007. © 2007 Wiley‐Liss, Inc.
A challenge for regenerative medicine: Proper genetic programming, not cellular mimicry
Authors: Rizzino Angie
Published: August 2007

Recent progress in stem cell biology and the reprogramming of somatic cells to a pluripotent phenotype has generated a new wave of excitement in regenerative medicine. Nonetheless, efforts aimed at understanding transdifferentiation, dedifferentiation, and the plasticity of cells, as well as the ability of somatic cells to be reprogrammed, has raised as many questions as those that have been answered. This review proffers the argument that many reports of transdifferentiation, dedifferentiation, and unexpected stem cell plasticity may be due to aberrant processes that lead to cellular look‐alikes (cellular mimicry). In most cases, cellular look‐alikes can now be identified readily by monitoring gene expression profiles, as well as epigenetic modifications of DNA and histone proteins of the cells involved. This review further argues that progress in regenerative medicine will be significantly hampered by failing to address the issue of cellular look‐alikes. Developmental Dynamics 236:3199–3207, 2007. © 2007 Wiley‐Liss, Inc.
Synthesis and Crystal Structure of New Early‐Lanthanide Organometallic Clusters
Authors: Barnea Eyal , Averbuj Claudia , Kapon Moshe , Botoshansky Mark , Eisen Moris S.
Published: August 2007

Reaction of Cp*2NdCl·LiCl·2thf (1) with excess catecholborane affords the hexameric cluster (Cp*NdCl2)6(LiCl)3(thf)3 (2) bearing three types of bridging chloride ions. Heating the reaction mixture affords the tetrameric cluster [(Cp*NdCl2)4(μ4‐Cl)]2[LiO2][LiO2*Li2O*O2] (3), which has the first crystal structure with the LiO2+ motif. Reaction of complex 1 or the analogous Sm complex, 4, with pinacolborane affords clusters 5a (Nd) or 5b (Sm), respectively, a second type of hexameric cluster built from two CpNd3Cl5(thf) units bonded by two μ2‐Cl atoms. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Role of biohydrogenation intermediates in milk fat depression
Authors: Shingfield Kevin J. , Griinari J. Mikko
Published: August 2007

Fat is the most variable constituent in milk and is reduced on low‐fiber/high‐concentrate diets or on rations containing lipid supplements rich in polyunsaturated fatty acids. The biohydrogenation theory attributes the causal mechanism underlying diet‐induced milk fat depression (MFD) to changes in ruminal lipid metabolism leading to increased formation of specific biohydrogenation intermediates that exert anti‐lipogenic effects. Trans‐10, cis‐12 conjugated linoleic acid (CLA) is the only intermediate shown unequivocally to inhibit milk fat synthesis. However, increases in ruminal trans‐10, cis‐12 CLA formation do not provide a universal explanation for the reductions in milk fat during diet‐induced MFD, suggesting that other biohydrogenation intermediates may also be involved. Post‐ruminal infusion experiments have provided tentative evidence that cis‐10, trans‐12 CLA and trans‐9, cis‐11 CLA also exert anti‐lipogenic effects. Diet‐induced MFD is consistently associated with an increase in milk fat trans‐10 18:1 concentrations, but recent direct evidence offers little support for a role of this intermediate in the regulation of milk fat synthesis. Further research is required to characterize the structure and function of other biohydrogenation intermediates, as well as considering the contribution of more global changes in ruminal lipid metabolism to provide a more universal explanation of diet‐induced MFD.
Diet, rumen biohydrogenation and nutritional quality of cow and goat milk fat
Authors: Chilliard Yves , Glasser Frédéric , Ferlay Anne , Bernard Laurence , Rouel Jacques , Doreau Michel
Published: August 2007

The potential to modify the milk fatty acid (FA) composition by changing the cow or goat diets is reviewed. Ruminal biohydrogenation (RBH), combined with mammary lipogenic and Δ‐9 desaturation pathways, considerably modifies the profile of dietary FA and thus milk composition. The pasture has major effects by decreasing saturated FA and increasing FA considered as favorable for human health (c9‐18:1, 18:3n‐3 andc9t11‐CLA), compared to winter diets, especially those based on maize silage and concentrates. Plant lipid supplements have effects similar to pasture, especially linseed, but they increase to a larger extent, simultaneously severaltransisomers of 18:1 and, conjugated or non‐conjugated 18:2, especially when added to maize silage or concentrate‐rich diets. The goat responds better for milk 18:3n‐3 andc9t11‐CLA, and sometimes less forc9‐18:1, and is less prone to the RBHtrans‐11 totrans‐10 shift, which has been shown to be time dependent in the cow. The respective physiological roles of most milktransFA have not been studied to date, and more studies in rodents and humans fed dairy products modified by changing ruminant diet are required before recommending a larger use of lipid sources and how to combine them with the different feeding systems used by dairy farmers.
Outlier detection in functional data by depth measures, with application to identify abnormal NOx levels
Authors: Febrero Manuel , Galeano Pedro , González‐Manteiga Wenceslao
Published: August 2007

This paper analyzes outlier detection for functional data by means of functional depths, which measures the centrality of a given curve within a group of trajectories providing center‐outward orderings of the set of curves. We give some insights of the usefulness of looking for outliers in functional datasets and propose a method based in depths for the functional outlier detection. The performance of the proposed procedure is analyzed by several Monte Carlo experiments. Finally, we illustrate the procedure by finding outliers in a dataset of NOx (nitrogen oxides) emissions taken from a control station near an industrial area. Copyright © 2007 John Wiley & Sons, Ltd.
In vivo imaging of brain lesions with [11C]CLINME, a new PET radioligand of peripheral benzodiazepine receptors
Authors: Boutin Hervé , Chauveau Fabien , Thominiaux Cyrille , Kuhnast Bertrand , Grégoire Marie‐Claude , Jan Sébastien , Trebossen Régine , Dollé Frédéric , Tavitian Bertrand , Mattner Filomena , Katsifis Andrew
Published: August 2007

The peripheral benzodiazepine receptor (PBR) is expressed by microglial cells in many neuropathologies involving neuroinflammation. PK11195, the reference compound for PBR, is used for positron emission tomography (PET) imaging but has a limited capacity to quantify PBR expression. Here we describe the new PBR ligand CLINME as an alternative to PK11195. In vitro and in vivo imaging properties of [11C]CLINME were studied in a rat model of local acute neuroinflammation, and compared with the reference compound [11C]PK11195, using autoradiography and PET imaging. Immunohistochemistry study was performed to validate the imaging data. [11C]CLINME exhibited a higher contrast between the PBR‐expressing lesion site and the intact side of the same rat brain than [11C]PK11195 (2.14 ± 0.09 vs. 1.62 ± 0.05 fold increase, respectively). The difference was due to a lower uptake for [11C]CLINME than for [11C]PK11195 in the non‐inflammatory part of the brain in which PBR was not expressed, while uptake levels in the lesion were similar for both tracers. Tracer localization correlated well with that of activated microglial cells, demonstrated by immunohistochemistry and PBR expression detected by autoradiography. Modeling using the simplified tissue reference model showed that R1 was similar for both ligands (R1 ∼ 1), with [11C]CLINME exhibiting a higher binding potential than [11C]PK11195 (1.07 ± 0.30 vs. 0.66 ± 0.15). The results show that [11C]CLINME performs better than [11C]PK11195 in this model. Further studies of this new compound should be carried out to better define its capacity to overcome the limitations of [11C]PK11195 for PBR PET imaging. © 2007 Wiley‐Liss, Inc.
Acetylcholinesterase inhibitors in assisted living: patterns of use and association with retention
Authors: Rosenblatt Adam , Samus Quincy M. , Onyike Chiadi U. , Baker Alva S. , McNabney Matthew , Mayer Lawrence S. , Brandt Jason , Lyketsos Constantine G.
Published: August 2007

Objectives

To describe patterns of Acetylcholinesterase inhibitor (ACI) use in an Assisted Living (AL) population, and the association of ACIs with retention in AL.

Methods

As part of the Maryland Assisted Living Study (MD–AL), 198 residents of 22 ALs were evaluated. Dementia was diagnosed in 134, and specifically Alzheimer's disease (AD) in 79, by an expert consensus panel. Data was collected on ACI agent and dose. Vital status and location were recorded every 6 months. Other data included age, duration of residence, general medical health rating (GHMR), Mini‐Mental State Examination (MMSE), Neuropsychiatric Inventory (NPI), Cornell Scale for Depression in Dementia (CSDD) and number of non‐psychiatric medications.

Results

The overall ACI treatment rate was 31%. 34.5% of participants with mild to moderate AD were taking ACIs. Only two in seven participants taking rivastigmine were taking an adequate dose. Participants with AD on ACI's did not differ significantly from those not on ACI's in any of the secondary measures except age and duration of residence, those on the agents being somewhat younger and more recently admitted. For participants with AD, only ACI use was significantly associated with retention in AL at 6 months, with a relative risk of death or discharge to higher level care of 0.217. Baseline MMSE was associated with retention for those with non‐AD dementia. In a survival analysis ACI use was associated with 228.75 days longer retention in participants with AD.

Conclusion

ACIs have low rates of use in AL and are associated with better retention for residents with AD. Copyright © 2007 John Wiley & Sons, Ltd.
Neutrophil dysfunction in alcoholic hepatitis superimposed on cirrhosis is reversible and predicts the outcome
Authors: Mookerjee Rajeshwar P. , Stadlbauer Vanessa , Lidder Sukhwinderjit , Wright Gavin A.K. , Hodges Stephen J. , Davies Nathan A. , Jalan Rajiv
Published: August 2007

Mortality in patients with alcoholic hepatitis (AH) remains high, and although corticosteroids are widely used for treatment, the results vary considerably. In AH, neutrophils are primed and infiltrate the liver to produce injury, but paradoxically, the main cause of death in such patients is infection. Our prospective study addressed this paradox of primed neutrophils on the one hand and increased risk of infection on the other. We hypothesized that the full activation of neutrophils by a humoral factor such as endotoxin renders them unable to respond to further bacterial challenge. We analyzed neutrophil oxidative burst and phagocytosis in whole blood by fluorescence-activated cell sorting analysis in 63 alcoholic patients with cirrhosis and patients with cirrhosis with superimposed AH (cirrhosis+AH). In 16 patients,

ex vivo

studies determined whether the removal of endotoxin restored neutrophil function. A resting burst greater than or equal to 5%, indicating neutrophil activation and a reduced phagocytic capacity lower than 42%, was associated with significantly greater risk of infection, organ failure, and mortality. This defective neutrophil function was transmissible through patients' plasma to normal neutrophils, and patients' neutrophil function could be restored by normal plasma. The

ex vivo

removal of endotoxin from patients' plasma decreased the resting burst and increased the phagocytic function.

Conclusions:

Our study provides the rationale for a goal-directed approach to the management of patients with cirrhosis and AH, in which the assessment of neutrophil function may be an important biomarker to select patients for immunosuppressive therapy. The neutrophil dysfunction in cirrhosis and AH is reversible, with endotoxin-removal strategies providing new targets for intervention. (Hepatology 2007.)
Receptor-mediated endocytosis of immune complexes in rat liver sinusoidal endothelial cells is mediated by FcγRIIb2
Authors: Mousavi Seyed Ali , Sporstφl Marita , Fladeby Cathrine , Kjeken Rune , Barois Nicolas , Berg Trond
Published: August 2007

Liver sinusoidal endothelial cells (LSECs) display a number of receptors for efficient uptake of potentially injurious molecules. The receptors for the Fc portion of immunoglobulin G (IgG) antibodies (FcγRs) regulate a number of physiological and pathophysiological events. We used reverse transcription polymerase chain reaction (RT-PCR) and Western blotting to determine the expression of different types of FcγRs in LSECs. Biochemical approaches and immunoflorescence microscopy were used to characterize the FcγR-mediated endocytosis of immune complexes (ICs). FcγRIIb2 was identified as the main receptor for the efficient uptake of ICs in LSECs. The receptor was shown to use the clathrin pathway for IC uptake; however, the association with lipid rafts may slow the rate of its internalization. Moreover, despite trafficking through lysosomal integral membrane protein-II (LIMP-II)–containing compartments, the receptor was not degraded. Finally, it was shown that the receptor recycles to the cell surface both with and without IC.

Conclusion:

FcγRIIb2 is the main receptor for endocytosis of ICs in rat LSECs. Internalized ICs are degraded with slow kinetics, and IC internalization is not linked to receptor downregulation. After internalization, the receptor recycles to the cell surface both with and without ICs. Thus, FcγRIIb2 in rat LSECs is used as both a recycling receptor and a receptor for efficient IC clearance. (Hepatology 2007.)
A novel algorithm for reliable detection of human papillomavirus in paraffin embedded head and neck cancer specimen
Authors: Smeets Serge J. , Hesselink Albertus T. , Speel Ernst‐Jan M. , Haesevoets Annick , Snijders Peter J.F. , Pawlita Michael , Meijer Chris J.L.M. , Braakhuis Boudewijn J.M. , Leemans C. René , Brakenhoff Ruud H.
Published: August 2007

Human papillomavirus type 16 (HPV16) plays a role in the development of a subgroup of head and neck squamous cell carcinomas (HNSCC). However, uncertainty exists about the true impact of HPV in this tumor type as conflicting reports have been published with prevalence rates from 0 to 100%. We aimed to find a detection algorithm of a biologically and thus clinically meaningful infection, applicable for high‐throughput screening of frozen and formalin‐fixed paraffin embedded (FFPE) specimens. By considering detection of HPV E6 oncogene expression in frozen biopsies as gold standard for a meaningful HPV infection, the value of several assays was evaluated on FFPE tumor specimens and sera of 48 HNSCC patients. The following assays were evaluated on FFPE tissue samples: HPV DNA general primer (GP)5+/6+ PCR, viral load analysis, HPV16 DNA FISH detection, HPV16 E6 mRNA RT‐PCR, p16 immunostaining, and on corresponding serum samples detection of antibodies against the HPV16 proteins L1, E6 and E7. Comparing single assays on FFPE tissue samples detection of E6 expression by RT‐PCR was superior, but application remains at present limited to HPV16 detection. Most suitable algorithm with 100% sensitivity and specificity appeared p16 immunostaining followed by GP5+/6+ PCR on the p16‐positive cases. We show that clinically meaningful viral HPV infections can be more reliably measured in FFPE HNSCC samples in a standard and high throughput manner, paving the way for prognostic and experimental vaccination studies, regarding not only HNSCC, but possibly also cancer types with HPV involvement in subgroups such as penile and anal cancer. © 2007 Wiley‐Liss, Inc.
The effects of EU shocks on the newly acceded countries
Authors: Barnett Alina
Published: August 2007

This paper analyses the response of seven of the newly acceded countries (NACs) to EU supply and monetary shocks. A typical NAC perceives an EU technology disturbance as a negative supply shock and an EU monetary expansion as a negative demand shock. When we split the seven countries into two groups, results for group 1 which includes the Czech Republic, Hungary, Poland and Slovakia suggest that an EU supply shock feeds through as a demand shock, increasing both prices and output. This suggests trade acts as a channel of EU shock propagation. Monetary disturbances explain 2% and 3% of the output fluctuation of group one and two and 10% and 42% of interest rate variations, respectively. EU shocks are identified as given by Canova and De Nicoló (2002) using sign restrictions of the cross‐correlation function of the variables' responses to orthogonal disturbances. These restrictions are derived from a DSGE model. Copyright © 2007 John Wiley & Sons, Ltd.
Fretting wear properties of hydroxyapatite, alumina containing high density polyethylene biocomposites against zirconia
Authors: Bodhak Subhadip , Nath Shekhar , Basu Bikramjit
Published: August 2007

Considering the importance of wear on the materials performance in biomedical applications, the major objective of the present work is to investigate the friction and fretting wear behavior of various HDPE‐based composites against zirconia counterbody, both in air and simulated body fluid (SBF) environment. Both Al2O3 and/or HAp fillers (upto 40 vol %) have been incorporated in HDPE to improve the hardness and elastic modulus of HDPE. The fretting wear study indicates that extremely low COF (∼0.055–0.075) as well as higher wear resistance (wear rate in the order of ∼10−6 mm3/N m) can be achieved with the newly developed composites in SBF. A low wear depth of 3–7 μm is recorded, irrespective of fretting environment. Besides reporting the phenomenological tribological data, major focus has been on to understand the underlying mechanism of material removal at fretting contacts. Such understanding has been established in discussing the wear mechanisms in terms of deformation of polymer matrix, tribolayer formation, and wear debris generation. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
A novel, tissue occlusive poly(ethylene glycol) hydrogel material
Authors: Wechsler Sandra , Fehr Daniel , Molenberg Aart , Raeber George , Schense Jason C. , Weber Franz E.
Published: August 2007

The use of guided bone regeneration (GBR) techniques requires new materials meeting the needs of clinical application. Design criteria for GBR devices are biocompatibility, tissue occlusion, space provision, and clinical manageability. This study evaluates a novel biodegradable poly (ethylene glycol) (PEG) based material as tissue occlusive membrane. A subcutaneous implant model in rats was developed to test the barrier function of the PEG hydrogels over time. Fourteen rats received three membrane implants and two positive controls each. Explants were collected over a period of 7 months. Histological analysis revealed that for at least 4 months cellular infiltration in the membrane explants was lower than 1% of that of the positive controls. Therefore, the PEG based hydrogel can be regarded as tissue occlusive during this period of time. A barrier function seems to be maintained for up to 6 months. In vitro degradation studies performed with the same PEG constructs confirm the in vivo result. In conclusion, our results indicate that this novel PEG‐based material has potential for use as a GBR barrier membrane. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Self‐crosslinkable hydrogels composed of partially oxidized hyaluronan and gelatin: In vitro and in vivo responses
Authors: Weng Lihui , Pan Hui , Chen Weiliam
Published: August 2007

Self‐crosslinkable hydrogels had been formulated from two precursors, partially oxidized hyaluronan (oHA) and gelatin. The physicochemical properties of the resulting hydrogels have been elucidated by instrumental analyses (FTIR, SEM, and rheometry). These hydrogels were highly porous with an average pore size of 60 μm, and evidently, accommodative to cell infiltration. Increasing the oxidation degree of oHA resulted in corresponding increases in hydrogels' storage moduli and decreases in water uptake. Dermal fibroblasts were used to study the cell–hydrogel interactions in vitro. Both the hydrogels and their degradation byproducts are biocompatible as indicated by long‐term cell viability assay. In addition, significant amount of cells migrated into the hydrogels and they aligned into highly organized arrays. When cultured with cells, the hydrogels underwent degradation within 4 weeks depending on composition with obvious loss of cohesiveness over time. The good biocompatibility and biodegradability of oHA/gelatin hydrogel were further demonstrated in mice subdermal implantations. Lastly, in vitro and in vivo depositions of extracellular matrix in hydrogels by cells were demonstrated by SEM analyses. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
The biodegradability of poly(Pro‐Hyp‐Gly) synthetic polypeptide and the promotion of a dermal wound epithelialization using a poly(Pro‐Hyp‐Gly) sponge
Authors: Tanihara Masao , Kajiwara Kazumi , Ida Keiko , Suzuki Yoshihisa , Kamitakahara Masanobu , Ogata Shin‐Ichi
Published: August 2007

Collagens are widely used in medical applications, but animal‐derived collagens have several drawbacks, such as low thermal stability, nonspecific cell attachment, and susceptibility to contamination by infectious pathogens, such as prions, which may transfect humans. We have previously reported the chemical synthesis of polypeptides consisting of a Pro‐Hyp‐Gly sequence and the high thermostability of their triple‐helical structure. To clarify the biomaterial characteristics of the poly(Pro‐Hyp‐Gly) polypeptide, we assessed its biodegradability and its capability for skin regeneration. Eight weeks after implantation, a poly(Pro‐Hyp‐Gly) freeze‐dried sponge embedded subcutaneously into a rat dorsal area degraded at the same rate as Terudermis®, which is made from bovine type I atelocollagen and is used as an artificial dermis. Surprisingly, compared with Terudermis, the poly(Pro‐Hyp‐Gly) sponge significantly promoted epithelialization of a full‐thickness wound on a rabbit's ear pad. This chemically synthesized polypeptide may be useful as a scaffold for tissue engineering and tissue regeneration. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Biomechanical response of condylar cartilage‐on‐bone to dynamic shear
Authors: Tanaka Eiji , Rego Emanuel B. , Iwabuchi Yasunori , Inubushi Toshihiro , Koolstra Jan Harm , van Eijden Theo M. G. J. , Kawai Nobuhiko , Kudo Yasusei , Takata Takashi , Tanne Kazuo
Published: August 2007

Shear stress can result in fatigue, damage, and irreversible deformation of the mandibular condylar cartilage. However, little information is available on its dynamic properties in shear. We tested the hypothesis that the dynamic shear properties of the condylar cartilage depend on the frequency and amplitude of shear strain. Ten porcine mandibular condyles were used for dynamic shear tests. Two cartilage‐bone plugs were dissected from each condyle and tested in a simple shear sandwich configuration under a compressive strain of 10%. Sinusoidal shear strain was applied with an amplitude of 1.0, 2.0, and 3.0% and a frequency range between 0.01 and 10 Hz. The magnitudes of the shear dynamic moduli were found to be dependent on the frequency and the shear strain amplitude. They increased with shear strain. tan δ ranged from 0.2 to 0.4, which means that the cartilage is primarily elastic in nature and has a small but not negligible viscosity. In conclusion, the present results show that the shear behavior of the mandibular condylar cartilage is dependent on the frequency and amplitude of the applied shear strain. The observed shear characteristics suggest a significant role of shear strain on the interstitial fluid flow within the cartilage. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008