bluuebunny/crossref_metadata_2025 huggingface dataset:
Depot specific differences during adipogenesis of porcine stromal‐vascular cells
Authors: Samulin Johanna , Lien Sigbjørn , Grindflek Eli , Berget Ingunn , Ruyter Bente , Sundvold Hilde
Published: January 2008

Recently a role of adipose tissue as an endocrine organ secreting factors involved in the regulation of whole‐body energy homeostasis has emerged. Preadipocytes in different fat depots have distinct adipogenic potential and the metabolic activity differs between mature adipocytes of different depot origins. Here we describe the proliferation and differentiation of stromal‐vascular cells derived from subcutaneous and visceral fat depots of adult pigs. We demonstrate that subcutaneous porcine preadipocytes proliferate more actively and that individual subcutaneous adipocytes have a more rapid accumulation of triacylglycerols than visceral cells. During differentiation, subcutaneous and visceral preadipocytes showed similar gene expression patterns with increased expression of adiponectin (APM1), adipocyte‐specific fatty acid binding protein (FABP4), catalase (CAT), and peroxisome proliferator‐activated receptor gamma 2 (PPARG2). Furthermore, initial data showing depot‐originated effects on the expression of CAT, carnitine palmitoyl transferase 1B (CPT1B) and FABP4 suggest possible depot specific differences in the function and metabolism of mature porcine adipocytes.
Aquaporin 1 expression in the testis, epididymis and vas deferens of postnatal ICR mice
Authors: Danyu Lu , Ying Li , Zhenwu Bi , Heming Yu , Xuejun Li
Published: January 2008

Aquaporin 1 (AQP1) is one of the water channels involved in water transfer and reabsorption. The results of a reverse transcription‐polymerase chain reaction (RT‐PCR) indicated that the level of AQP1 mRNA was increased in the testis and vas deferens, but decreased in the epididymis from the early postnatal period through puberty to adulthood. The results of Western blot analyses largely matched the RT‐PCR findings for AQP1. AQP1 was immunohistochemically localized on the plasma membrane in the epithelia of rete testis and vas deferens at postnatal day 70, although it was hardly detectable at postnatal day 15. Nevertheless, AQP1 was expressed in the epithelia of the efferent duct and the initial segment of caput epididymis at postnatal day 15 and persisted into adulthood. The results taken together suggest that the expression and localization of AQP1 in mouse testis, epididymis and vas deferens are a stage‐, tissue‐ and region‐specific pattern and provide obvious clues that a possible relationship exists between the functional application of AQP1 for water reabsorption, and male reproduction and maturation.
Mechanical stimulation of C2C12 cells increases m‐calpain expression, focal adhesion plaque protein degradation
Authors: Grossi Alberto , Karlsson Anders H. , Lawson Moira A.
Published: January 2008

Myogenesis is a complex sequence of events, including the irreversible transition from the proliferation‐competent myoblast stage into fused, multinucleated myotubes. During embryonic development, myogenic differentiation is regulated by positive and negative signals from surrounding tissues. Stimulation due to stretch‐ or load‐induced signaling is now beginning to be understood as a factor which affects gene sequences, protein synthesis and an increase in Ca2+ influx in myocytes. Evidence of the involvement of Ca2+‐dependent activity in myoblast fusion, cell membrane and cytoskeleton component reorganization due to the activity of the ubiquitous proteolytic enzymes, calpains, has been reported. Whether there is a link between stretch‐ or load‐induced signaling and calpain expression and activation is not known. Using a magnetic bead stimulation assay and C2C12 mouse myoblasts cell population, we have demonstrated that mechanical stimulation via laminin receptors leads to an increase in m‐calpain expression, but no increase in the expression of other calpain isoforms. Our study revealed that after a short period of stimulation, m‐calpain relocates into focal adhesion complexes and is followed by a breakdown of specific focal adhesion proteins previously identified as substrates for this enzyme. We show that stimulation also leads to an increase in calpain activity in these cells. These data support the pivotal role for m‐calpain in the control of muscle precursor cell differentiation and thus strengthen the idea of its implication during the initial events of muscle development.
PIKfyve: Partners, significance, debates and paradoxes
Authors: Shisheva Assia
Published: January 2008

Key components of membrane trafficking and signaling machinery in eukaryotic cells are proteins that bind or synthesize phosphoinositides. PIKfyve, a product of an evolutionarily conserved single‐copy gene has both these features. It binds to membrane phosphatidylinositol (PtdIns)3P and synthesizes PtdIns(3,5)P2 and PtdIns5P. Molecular functions of PIKfyve are elusive but recent advances are consistent with a key role in the course of endosomal transport. PIKfyve dysfunction induces endosome enlargement and profound cytoplasmic vacuolation, likely as a result of impaired normal endosome processing and membrane exit out of endosomes. Multicellular organisms with genetically impaired function of PIKfyve or that of the PIKfyve protein partners regulating PtdIns(3,5)P2 homeostasis display severe disorders, including embryonic/perinatal death. This review describes recent advances on PIKfyve functionality in higher eukaryotes, with particular reference to biochemical and genetic insights in PIKfyve protein partners.
Alterations of estrogen receptors, progesterone receptors and c‐erbB2 oncogene protein expression in ductal carcinomas of the breast
Authors: Hussein Mahmoud R. , Abd‐Elwahed Saad R.A.H. , Abdulwahed Ahmad Rezk
Published: January 2008

Estrogens are important for stimulating the growth of a large proportion of breast cancers. Progesterone plays critical roles in breast development and tumorigenesis. The c‐erbB2 gene (HER‐2/neu) is a proto‐oncogene expressed in 10–34% of breast cancers. Its expression is associated with poor clinical outcome. The hypothesis that the progression of in situ ductal carcinoma of breast to invasive ductal carcinoma is associated with alterations of ER, PgR and HER‐2/neu protein expression was tested. Of 100 mastectomy specimens examined, all contained both ductal carcinoma in situ (DCIS) and invasive ductal carcinomas (IDC) not otherwise specified (NOS). The status of ER, PgR and HER‐2/neu proteins was examined by immunochemistry. ER and PgR protein expression was scored as the mean value of positively stained cells. HER‐2/neu protein expression was evaluated on ts staining pattern (0, 1+, 2+ and 3+). We found variations between DCIS and IDC with significant decrease of the mean values of ER and PgR positively stained cells in high‐grade (Grade 3) IDC (ER: 49.2 ± 10.3 vs. 30.8 ± 5.5 and PgR: 40.0 ± 10.0 vs. 22.3 ± 5.1 in DCIS and IDC, respectively, P < 0.05). Invasive carcinomas with lymph node metastases or lymphovascular invasion or both had lower mean values of ER and PgR positively stained cells compared to those without these features. In IDC (Grade 3), HER‐2/neu protein expression values (1.2 ± 0.2) were significantly high compared to DCIS (0.7 ± 0.3, P < 0.05). In addition, HER‐2/neu protein expression values were significantly higher (P < 0.05) in IDC with lymph node metastases or lymphovascular invasion (1.5 ± 0.3) than those without these features (0.8 ± 0.2). A significantly high mean (P < 0.05) of ER and PgR positively stained cells was observed in postmenopausal females compared to premenopausal women. In contrast, high HER‐2/neu expression values were seen only in premenopausal females. A significant positive correlation was observed between ER and PgR receptor expression (r = 0.81). A low degree inverse correlation (r = −0.24, P < 0.012) was found between ER+/PgR+ tumors and HER‐2/neu expression. These findings substantiate the notion that breast cancer progression is often associated with alterations of ER, PgR and HER‐2/neu expression. The underlying mechanisms of these alterations are open for further investigation.
Piezoelectricity and prostate cancer: Proposed interaction between electromagnetic field and prostatic crystalloids
Authors: Ghabili Kamyar , Shoja Mohammadali M. , Agutter Paul S.
Published: January 2008

There is evidence that electromagnetic fields (EMF) play some part in the pathogenesis of prostate cancer, but the pathogenic mechanism remains unknown. The normal prostate gland and both benign and malignant prostate lesions contain abundant calcium/phosphorus crystalloids with various morphologies, which seem to be heterogeneously and diffusely distributed within the gland. We hypothesize that an environmental EMF may result in simultaneous, multidirectional and diffuse compression or expansion of these crystalloids (a piezoelectric effect). This would result in a slight mechanical distortion of the prostate, potentially altering cell behavior and enhancing the expression of specific genes, particularly those involved in suppressing apoptosis. A mathematical model of the cell mechanical effect is presented, and the hypothesis is related to current clinical evidence and to potential validation by critical laboratory tests.
Magnetosonic solitons in a dusty plasma slab
Authors: MARKLUND M. , STENFLO L. , SHUKLA P. K.
Published: January 2008

The existence of magnetosonic solitons in dusty plasmas is investigated. The nonlinear magnetohydrodynamic equations for a warm dusty magnetoplasma are thus derived. A solution of the nonlinear equations is presented. It is shown that, owing to the presence of dust, static structures are allowed. This is in sharp contrast to the formation of the so-called shocklets in usual magnetoplasmas. A comparatively small number of dust particles can thus drastically alter the behavior of the nonlinear structures in magnetized plasmas.
Honoré Fabri and the Trojan Horse of Inertia
Authors: Elazar Michael
Published: January 2008

Argument

This paper discusses the theory of motion of the philosopher Honoré Fabri (1608–1688), a senior representative of early modern Jesuit scientists. It argues that the consensus prevailing among historians – according to which Fabri's theory of impetus is diametrically opposed to Galileo's or Descartes' concept of inertia – is false. It shows: that Fabri carefully constructed his concept of impetus in order to easily incorporate the principle of linear conservation of motion (designated here as “limited inertia”), by adopting formal (rather than efficient) causality between impetus and motion and by allowing impetus to act only along straight lines; that he explicitly deemed Aristotle's famous “inertial paradox” not as a paradox at all; and that linear conservation of motion was not limited to “counterfactual” circumstances but played a significant part in his discrete theory of free fall and constituted an integral component of his general physical (and even mathematical) philosophy. However, the paper also shows that Fabri's notion of inertia was restricted to one dimension only, and therefore should indeed be considered “limited.” In his analysis of horizontal projectiles, Fabri explicitly rejected Galileo's important principle of superposition, and thus revealed significant constraints to his “inertial” thinking.
Writing “The Case of Ellen West”: Clinical Knowledge and Historical Representation
Authors: Akavia Naamah
Published: January 2008

Argument

“The Case of Ellen West” was published by the Swiss psychiatrist, Ludwig Binswanger, in 1944–1945. The case-history depicts the illness and suicide of a young woman who was his patient twenty years earlier. It came to be considered one of the paradigmatic studies of the newly established discipline ofDaseinsanalyse, an attempt to synthesize existential philosophy and therapeutic practice. This paper analyzes the case-study, employing newly uncovered archival material to expose important details regarding the treatment of Ellen West (a pseudonym) and the posthumous writing of her case-history. The richness of the archival sources and the various historiographical characteristics they exhibit raise methodological questions about the potentialities and limitations of historical representation. The new data will thus serve as a platform from which to explore and discuss more generally the problems involved in historical reconstruction – of both subjective experience and clinical knowledge – and the questions of authorship and intertextuality in the genre of the case-history.
MECHANICAL HEART VALVES AND PREGNANCY
Authors: MAXWELL CYNTHIA , SERMER MATHEW
Published: January 2008

Mechanical heart valves pose a particular challenge in pregnancy, as the primary agent used to prevent valve thrombosis, coumadin (warfarin), is a known teratogen. Alternatives to coumadin, such as unfractionated heparin (UFH) and low-molecular weight heparin (LMWH) are safer for the fetus, particularly during the first trimester of pregnancy, but expose the mother to potential valve failure. This review will examine these controversies and the complex literature regarding management in pregnancy.
Genetik autistischer Störungen
Authors: Freitag Christine M.
Published: January 2008

Zusammenfassung: Autistische Störungen sind heterogene Erkrankungen. Die Betroffenen zeigen Einschränkungen der Kommunikation und sozialen Interaktion und stereotypes, repetitives Verhalten sowie Sonderinteressen. Der überwiegende Teil der autistischen Störungen sind genetisch bedingt. In dem Artikel wird eine Übersicht über zytogenetische Veränderungen sowie molekulargenetische Kopplungs- und Assoziationsstudien gegeben. Wichtige Differentialdiagnosen werden beschrieben. Die Ergebnisse dieser Studien haben eine besondere Bedeutung für die genetische Beratung der Familien.
Modern Facet Theory: Content Design and Measurement in Behavioral Research
Authors: Shye Samuel
Published: January 2008

Facet Theory is a research strategy that integrates formal analysis of research contents (using the tool of the mapping sentence) with intrinsic data analysis (multivariate procedures such as Faceted Smallest Space Analysis (FSSA) and Multiple Scaling by Partial Order Scalogram Analysis by base Coordinates (POSAC)). The integration of content design and data analysis is argued to be essential for theory construction and meaningful measurement in the behavioral sciences that typically study complex systems with many, possibly infinitely many, variables. Mapping sentences permit the balanced selection of observational variables from the content universe studied. Focusing on observed variables (columns of the data matrix), FSSA creates a geometric representation of the concept-space and partitions it into regions, thus enabling the systematic investigation of the concept structure. Focusing on the observed individuals (rows of the data matrix), POSAC provides optimal measurement scales for the individuals' assessment. Traditional prediction models assume the existence of factors (underlying variables), by which both variables and individuals can be evaluated, which determine empirical observations. Modern facet theory shows that two kinds of factors are at work: facets (partitionings) of the concept-space, for evaluating variables; and scales (coordinates) of the measurement space, for evaluating individuals. The two factor types point to two roads for attaining the goal of prediction. Mathematical results in Multiple Scaling, and especially the introduction of the newly devised coefficient of structural similarity, contribute to the convergence of the two roads.
Use of the TOEFL as a Standard for University Admission: A Position Statement by the Canadian Psychological Association
Authors: Simner Marvin L.
Published: January 2008

Nearly all Canadian universities employ, as a standard for university admission, the Test of English as a Foreign Language (TOEFL). In light of considerable evidence indicating only a weak relationship between TOEFL scores and academic achievement, the Canadian Psychological Association recently issued a report containing a position statement that called upon Canadian universities to refrain from employing the TOEFL in this manner. Because the concerns raised in the report are likely to apply to many universities outside Canada, the entire report is reproduced in this article.
Negative Numbers Are Generated in the Mind
Authors: Ganor-Stern Dana , Tzelgov Joseph
Published: January 2008

Abstract. The goal of the present study was to disentangle two possible representations of negative numbers - the holistic representation, where absolute magnitude is integrated with polarity; and the components representation, where absolute magnitude is stored separately from polarity. Participants' performance was examined in two tasks involving numbers from -100 to 100. In the numerical comparison task, participants had to decide which number of a pair was numerically larger/smaller. In the number line task, participants were presented with a spatial number line on which they had to place a number. The results of both tasks support the components representation of negative numbers. The findings suggest that processing of negative numbers does not involve retrieval of their meaning from memory, but rather the integration of the polarity sign with the digits' magnitudes.
Early Activity in the Lateralized Readiness Potential Suggests Prime-Response Retrieval as a Source of Negative Priming
Authors: Gibbons Henning , Stahl Jutta
Published: January 2008

Abstract. Negative priming (NP) refers to increased response time (RT) for a probe target that was a distractor in a preceding prime presentation (distractor-target shift, DT), compared to novel targets. The present study used the lateralized readiness potential (LRP) to investigate, in a four-choice identification task, a novel episodic-retrieval explanation of NP introduced by Rothermund, Wentura, and de Houwer (2005) . This theory proposes that retrieval reactivates the prime response which interferes with selection of the correct probe response, thereby producing NP. 20 participants responded to pairs of red and blue digits, contingent on the identity of the digit presented in the target color. Behavioral NP involved RT increase by 16 ms. With shift trials (different hands used for prime and probe responses), in the DT condition LRP onset was delayed relative to control. By contrast, earlier LRP onset was observed for DT relative to control with no-shift trials (same hand used for prime and probe responses). Behavioral NP effects showed similar magnitude for shift and no-shift trials. Results support the Rothermund et al. (2005) theory of prime-response retrieval.
“The” Interpretation(s) of Conditionals
Authors: Schroyens Walter , Schaeken Walter , Dieussaert Kristien
Published: January 2008

Abstract. Recent studies indicate that a vast majority of people judge the probability of a conditional  as equivalent to the conditional probability of . This means that in evaluating the applicability of a conditional people do not seem to take into account situations in which the antecedent  is false. This has been taken as evidence against the model theory of Johnson-Laird and Byrne (2002) . This theory, however, claims that the conditional interpretation in which false-antecedent cases are relevant is only one of many possible interpretations of “if.” We present new evidence that confirms this flexibility of the interpretive system. When people are primed by thinking (1) about truth and the difference between the  and  or (2) are invited to judge which situations are consistent with the conditional, they are more likely to select a probability estimate that takes into account the false-antecedent cases.
On the (Mis)Categorization of Unattractive Brides and Attractive Prostitutes
Authors: Ruys Kirsten I. , Dijksterhuis Ap , Corneille Olivier
Published: January 2008

Abstract. Numerous studies have shown that social categorization is a flexible process that partly depends on contextual variables. However, little is known about the role of affect in people's access to categorical dimensions. We investigated the hypothesis that social category activation is facilitated on evaluatively congruent dimensions. Two studies provide support for this evaluative-matching hypothesis, in which social categorization was found to be faster and more accurate for evaluatively congruent categories (i.e., unattractive foreigners, unattractive prostitutes, attractive fellow-citizens and attractive brides) than for evaluatively incongruent categories (i.e., attractive foreigners, attractive prostitutes, unattractive fellow-citizens and unattractive brides). We discuss the theoretical and practical implications of these findings.
A multiaxial growth analysis of stable isotopes in the modern shell of Saxidomus gigantea: Implications for sclerochronology studies
Authors: Kingston Andrew W. , Gröcke Darren R. , Burchell Meghan
Published: January 2008

Stable‐isotope ratios of two modern Saxidomus gigantea specimens from Namu, British Columbia, are presented to show intraspecimen and interspecimen isotopic variation. Isotopic profiles (δ13Cshell, δ18Oshell) were generated along the axis of maximum growth. The profiles show that analogous seasonal variation is recorded in δ18Oshell; however, significant variability is recorded in δ13Cshell. We suggest this is caused by differences in metabolic activity between individuals. Intrashell variability along a growth horizon shows good reproducibility in δ13Cshell but significant variability in δ18Oshell, especially at the sinistral margin. A multiaxial growth analysis generated several profiles from a single valve. Similar seasonal variations are recorded in δ18Oshell along all axes. δ13Cshell show significantly less covariation, possibly related to internal metabolic activity. This study highlights that δ18Oshell profiles generated from any portion of the shell can be used to evaluate seasonal fluctuations and may be excellent to evaluate types and rates of shell growth.
Arctic Ocean surface warming trends over the past 100 years
Authors: Steele Michael , Ermold Wendy , Zhang Jinlun
Published: January 2008

Ocean temperature profiles and satellite data have been analyzed for summertime sea surface temperature (SST) and upper ocean heat content variations over the past century, with a focus on the Arctic Ocean peripheral seas. We find that many areas cooled up to ∼0.5°C per decade during 1930–1965 as the Arctic Oscillation (AO) index generally fell, while these areas warmed during 1965–1995 as the AO index generally rose. Warming is particularly pronounced since 1995, and especially since 2000. Summer 2007 SST anomalies are up to 5°C. The increase in upper ocean summertime warming since 1965 is sufficient to reduce the following winter's ice growth by as much as 0.75 m. Alternatively, this heat may return to the atmosphere before any ice forms, representing a fall freeze‐up delay of two weeks to two months. This returned heat might be carried by winds over terrestrial tundra ecosystems, contributing to the local heat budget.
Titan's inventory of organic surface materials
Authors: Lorenz Ralph D. , Mitchell Karl L. , Kirk Randolph L. , Hayes Alexander G. , Aharonson Oded , Zebker Howard A. , Paillou Phillipe , Radebaugh Jani , Lunine Jonathan I. , Janssen Michael A. , Wall Stephen D. , Lopes Rosaly M. , Stiles Bryan , Ostro Steve , Mitri Giuseppe , Stofan Ellen R.
Published: January 2008

Cassini RADAR observations now permit an initial assessment of the inventory of two classes, presumed to be organic, of Titan surface materials: polar lake liquids and equatorial dune sands. Several hundred lakes or seas have been observed, of which dozens are each estimated to contain more hydrocarbon liquid than the entire known oil and gas reserves on Earth. Dark dunes cover some 20% of Titan's surface, and comprise a volume of material several hundred times larger than Earth's coal reserves. Overall, however, the identified surface inventories (>3 × 104 km3 of liquid, and >2 × 105 km3 of dune sands) are small compared with estimated photochemical production on Titan over the age of the solar system. The sand volume is too large to be accounted for simply by erosion in observed river channels or ejecta from observed impact craters. The lakes are adequate in extent to buffer atmospheric methane against photolysis in the short term, but do not contain enough methane to sustain the atmosphere over geologic time. Unless frequent resupply from the interior buffers this greenhouse gas at exactly the right rate, dramatic climate change on Titan is likely in its past, present and future.
A changing Arctic seasonal ice zone: Observations from 1870–2003 and possible oceanographic consequences
Authors: Kinnard Christophe , Zdanowicz Christian M. , Koerner Roy M. , Fisher David A.
Published: January 2008

Changes in the extent of seasonal ice were investigated using historical and satellite observations for the period 1870–2003. The seasonal ice zone (SIZ) has been gradually expanding since 1870, with a marked acceleration over the past three decades, and has migrated north to encompass all peripheral Arctic seas. The expansion of the SIZ may be increasing the salinity of the upper Arctic Ocean, consistent with recent observations. The migration of the SIZ over continental shelves may also be enhancing the formation rate and salinity of Arctic deep waters, which are subsequently advected to the convective region of the Greenland‐Iceland‐Norwegian Sea, thereby influencing the formation of North Atlantic deep waters and related global thermohaline circulation.
A new model for Double Diffusion + Turbulence
Authors: Canuto V. M. , Cheng Y. , Howard A. M.
Published: January 2008

Available models of Double Diffusion (DD) processes (Salt Fingers, SF and Diffusive Convection, DC) are primarily based on laboratory experiments that do not include turbulence which is however always present in the ocean. A reliable DD model for use in OGCMs (ocean global circulation models) is therefore still lacking and a true assessment of the role of oceanic DD is yet to be made. Here, we derive and validate a new model for DD + Turbulence using a second‐order closure model which differs significantly from previous ones in that the ratios of the correlation time scales to the dissipation time scales, constant in previous models, now depend on Ri and Rρ, the key new feature needed to reproduce both laboratory (no shear) and oceanic (with shear) data. The model can therefore be used in OGCMs. The full mixing model includes mixed layer, internal gravity waves, DD and tides.
Rise in frequency of surface melting at Siple Dome through the Holocene: Evidence for increasing marine influence on the climate of West Antarctica
Authors: Das Sarah B. , Alley Richard B.
Published: January 2008

A new melt layer history from Siple Dome, West Antarctica, indicates notable late‐Holocene summertime warming. Visual stratigraphic analyses of the 1004‐m ice core identified 62 years with melt layers. Melting events began around 11.7 ka, followed by a period of no melting from 8.8–6.6 ka. Melt layer frequency increased from 6.6 ka to the present, with the 1000‐year‐average melt layer frequency reaching a maximum of 2% at 0.8 ka. We use our millennial‐scale archive of melt events as a unique seasonal paleothermometer to elucidate changes in West Antarctic Holocene summer climate. Our calibration suggests the change in melt frequency from 0% to 2% may represent a summer temperature increase of ≥2°C from the middle to late Holocene. This temperature change cannot be explained entirely by local change in ice elevation or summer insolation and is in contrast to East Antarctic climate records, which show peak warmth in the early Holocene followed by stable or decreasing temperature. We interpret the rise in melt frequency as evidence of an increasing marine influence on the Ross Sea sector of West Antarctica. Although the surface elevation of Siple Dome has not changed greatly, the continued lateral retreat of the West Antarctic ice sheet from its Last Glacial Maximum configuration (across the outer continental shelf), and the delayed drawdown in ice thickness from the adjacent coastal Marie Byrd Land region, in conjunction with periods of increased cyclogenesis, perhaps related to variations in ENSO, would allow a moderated maritime climate to more easily reach West Antarctica.
Combining inhaled glucocorticoids and long acting β2‐adrenoceptor agonists in asthma and COPD
Authors: Knox A J , Mortimer K
Published: January 2008

Inhaled long‐acting β2‐adrenoceptor agonists and glucocorticoids form the mainstay of maintenance treatment of asthma and chronic obstructive pulmonary disease (COPD), usually given as a combination inhaler. Most patients will have good asthma control if they comply with this therapy, although it is generally less effective in COPD. The traditional dogma has been that these agents act on distinct components of disease pathophysiology with β2 agonists acting on the bronchospastic component and glucocorticoids acting on the inflammatory component. Considerable evidence has emerged recently, however, to suggest that these two classes of agents interact at a molecular level. Understanding the mechanisms of these interactions may enable the development of new therapies for asthma and COPD.

British Journal of Pharmacology (2008) 153, 1085–1086; doi:10.1038/bjp.2008.4; published online 28 January 2008
Formulation and in vitro Evaluation of Eudragit L100 piroxicam
Authors: Saffari Mostafa , Shahbazi Malihe , Shafiee Ardestani Mehdi
Published: January 2008

The aim of this study was to formulate and evaluate controlled release preparations of a water-insoluble drug using Copolymers synthesized from acrylic and methacrylic acidesters (Eudragit L 100) as the retardant material. Microspheres were prepared by solvent evaporation method using an alcohol / liquid paraffin system. Span60 was used as the droplet stabilizer. The prepared microspheres were characterized for their micromeritic properties and drug loading, as well as by differential scanning calorimetry. The in vitro release studies were performed first in pH1.2 and then pH 6.8, phosphate buffer. The prepared microspheres were yellow, and spherical in shape. The drugloaded microspheres showed 71-85% of entrapment and release was extended up to 7 h. The differential scanning calorimetry thermographs showed stable character of drug in the drug-loaded microspheres and revealed the absence of drug-polymer interactions. The best-fit release kinetics was achieved with Higuchi plot. The release of drug was influenced by the drug to polymer ratio and particle size that was found to be diffusion controlled.
Neuroprotective effect of hydrogen peroxide on an in vitro model of brain ischaemia
Authors: Nisticò R , Piccirilli S , Cucchiaroni M L , Armogida M , Guatteo E , Giampà C , Fusco F R , Bernardi G , Nisticò G , Mercuri N B
Published: January 2008

Background and purpose:

Reactive oxygen species (ROS) have been postulated to play a crucial role in the pathogenesis of ischaemia‐reperfusion injury. Among these, hydrogen peroxide (H2O2) is known to be a toxic compound responsible for free‐radical‐dependent neuronal damage. In recent years, however, the ‘bad reputation’ of H2O2 and other ROS molecules has changed. The aim of this study was to assess the protective role of H2O2 and modification in its endogenous production on the electrophysiological and morphological changes induced by oxygen/glucose deprivation (OGD) on CA1 hippocampal neurons.

Experimental approach:

Neuroprotective effects of exogenous and endogenous H2O2 were determined using extracellular electrophysiological recordings of field excitatory post synaptic potentials (fEPSPs) and morphological studies in a hippocampal slice preparation. In vitro OGD was delivered by switching to an artificial cerebrospinal fluid solution with no glucose and with oxygen replaced by nitrogen.

Key results:

Neuroprotection against in vitro OGD was observed in slices treated with H2O2 (3 mM). The rescuing action of H2O2 was mediated by catalase as pre‐treatment with the catalase inhibitor 3‐amino‐1,2,4‐triazole blocked this effect. More interestingly, we showed that an increase of the endogenous levels of H2O2, due to a combination of an inhibitor of the glutathione peroxidase enzyme and addition of Cu,Zn‐superoxide dismutase in the tissue bath, prevented the OGD‐induced irreversible depression of fEPSPs.

Conclusions and implications:

Taken together, our results suggest new possible strategies to lessen the damage produced by a transient brain ischaemia by increasing the endogenous tissue level of H2O2.

British Journal of Pharmacology (2008) 153, 1022–1029; doi:10.1038/sj.bjp.0707587; published online 28 January 2008
Prolonged treatment of cells with genistein modulates the expression and function of the cystic fibrosis transmembrane conductance regulator
Authors: Schmidt A , Hughes L K , Cai Z , Mendes F , Li H , Sheppard D N , Amaral M D
Published: January 2008

Background and purpose:

Cystic fibrosis (CF) is caused by dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl− channel. In the search for new CF therapies, small molecules have been identified that rescue the defective channel gating of CF mutants (termed CFTR potentiators). Here, we investigate the long‐term effects of genistein, the best‐studied CFTR potentiator, on the expression and function of CFTR.

Experimental approach:

We pre‐treated baby hamster kidney (BHK) cells expressing wild‐type or F508del‐CFTR (the most common CF mutant) with concentrations of genistein that potentiate (30 μM) or inhibit (100 μM) CFTR function for 2 or 24 h at 37 °C before examining CFTR maturation, expression and single‐channel activity.

Key results:

Using the iodide efflux technique, we found that genistein pre‐treatment failed to restore function to F508del‐CFTR, but altered that of wild‐type CFTR. Pre‐treatment of cells with genistein for 2 h had little effect on CFTR processing, whereas pre‐treatment for 24 h either augmented (30 μM genistein) or impaired (100 μM genistein) CFTR maturation. Using immunocytochemistry, we found that all genistein pre‐treatments increased the localization of CFTR protein to the cell surface. However, following the incubation of cells with genistein (100 μM) for 2 h, individual CFTR Cl− channels exhibited characteristics of channel block upon channel activation.

Conclusions and implications:

Genistein pre‐treatment alters the maturation, cell surface expression and single‐channel function of CFTR in ways distinct from its acute effects. Thus, CFTR potentiators have the potential to influence CFTR by mechanisms distinct from their effects on channel gating.

British Journal of Pharmacology (2008) 153, 1311–1323; doi:10.1038/sj.bjp.0707663; published online 28 January 2008
The role of endocannabinoids in the regulation of gastric emptying: alterations in mice fed a high‐fat diet
Authors: Di Marzo V , Capasso R , Matias I , Aviello G , Petrosino S , Borrelli F , Romano B , Orlando P , Capasso F , Izzo A A
Published: January 2008

Background and purpose:

Endocannabinoids (via cannabinoid CB1 receptor activation) are physiological regulators of intestinal motility and food intake. However, their role in the regulation of gastric emptying is largely unexplored. The purpose of the present study was to investigate the involvement of the endocannabinoid system in the regulation of gastric emptying in mice fed either a standard diet (STD) or a high‐fat diet (HFD) for 14 weeks.

Experimental approach:

Gastric emptying was evaluated by measuring the amount of phenol red recovered in the stomach after oral challenge; CB1 expression was analysed by quantitative reverse transcription‐PCR; endocannabinoid (anandamide and 2‐arachidonoyl glycerol) levels were measured by liquid chromatography‐mass spectrometry.

Key results:

Gastric emptying was reduced by anandamide, an effect counteracted by the CB1 receptor antagonist rimonabant, but not by the CB2 receptor antagonist SR144528 or by the transient receptor potential vanilloid type 1 (TRPV1) antagonist 5′‐iodoresiniferatoxin. The fatty acid amide hydrolase (FAAH) inhibitor N‐arachidonoyl‐5‐hydroxytryptamine (but not the anandamide uptake inhibitor OMDM‐2) reduced gastric emptying in a way partly reduced by rimonabant. Compared to STD mice, HFD mice exhibited significantly higher body weight and fasting glucose levels, delayed gastric emptying and lower anandamide and CB1 mRNA levels. N‐arachidonoylserotonin (but not rimonabant) affected gastric emptying more efficaciously in HFD than STD mice.

Conclusions and implications:

Gastric emptying is physiologically regulated by the endocannabinoid system, which is downregulated following a HFD leading to overweight.

British Journal of Pharmacology (2008) 153, 1272–1280; doi:10.1038/sj.bjp.0707682; published online 28 January 2008
High current ion beam transport using solenoids
Authors: Hollinger R. , Spädtke P.
Published: January 2008

In the framework of the future project FAIR several upgrade programs and construction of new facilities are in progress such as the U4+ upgrade for the existing high current injector and the new 70MeV proton injector. For both injectors solenoids in the low energy beam transport section are foreseen to inject the beam into the following rf accelerator. The paper presents beam quality measurements of high current ion beams behind a solenoid using a slit-grid emittance measurement device, viewing targets, and a pepper pot measurement device at the high current test bench at GSI.
Enhancement of SPES source performances
Authors: Fagotti E. , Palmieri A. , Ren X.
Published: January 2008

Installation of SPES source at LNL was finished in July 2006 and the first beam was extracted in September 2006. Commissioning results confirmed very good performance of the extracted current density. Conversely, source reliability was very poor due to glow-discharge phenomena, which were caused by the ion source axial magnetic field protruding in the high-voltage column. This problem was fixed by changing the stainless steel plasma electrode support with a ferromagnetic one. This new configuration required us to recalculate ion source solenoids positions and fields in order to recover the correct resonance pattern. Details on magnetic simulations and experimental results of high voltage column shielding are presented.
Studies on x-ray and UV emissions in electron cyclotron resonance x-ray source
Authors: Baskaran R. , Selvakumaran T. S.
Published: January 2008

A novel electron cyclotron resonance x-ray source is constructed based on the ECR technique. In this paper, the possibility of using the ECR x-ray source for producing UV rays by optimizing the plasma parameters is explored. X-ray and UV emissions from the ECR x-ray source are carried out for argon, nitrogen, and CO2 plasma. The x-ray spectral and dose measurements are carried with NaI(Tl) based spectrometer and dosimeter, respectively. For UV measurement, a quartz window arrangement is made at the exit port and the UV intensity is measured at 5cm from the quartz plate using UV meter. The x-ray and UV emissions are carried out for different microwave power levels and gas pressures. The x-ray emission is observed in the pressure range ⩽10−5Torr, whereas the UV emission is found to be negligible for the gas pressures <10−5Torr and it starts increasing in the pressure range between 10−5 and 10−3Torr. At high-pressure range, collision frequency of electron-atom is large which leads to the higher UV flux. At low pressure, the electron-atom collision frequency is low and hence the electrons reach high energy and by hitting the cavity wall produces higher x-ray flux. By choosing proper experimental conditions and plasma gas species, the same source can be used as either an x-ray source or an UV source.
Computer simulation of charged hard spherocylinders
Authors: Avendaño Carlos , Gil-Villegas Alejandro , González-Tovar Enrique
Published: January 2008

In this work we present a computer simulation study of charged hard spherocylinders of aspect ratio L∕σ=5, using NVT and NPT Monte Carlo methods. Coulombic interactions are handled using the Wolf method [D. Wolf, P. Keblinski, S. R. Phillpot, and J. Eggebrecht, J. Chem. Phys. 110, 8254 (1999)]. Thermodynamic and structural properties are in excellent agreement with the results obtained with the standard Ewald summation method. A partial prediction of the corresponding phase diagram is obtained by studying two isotherms of this system. The stability of the liquid crystalline phases is examined and compared with the phase diagrams of neutral hard spherocylinders and dipolar hard spherocylinders.
Thin-thick surface phase coexistence and boundary tension of the square-well fluid on a weak attractive surface
Authors: Singh Jayant K. , Sarma Gautam , Kwak Sang K.
Published: January 2008

Prewetting transition is studied for the square-well fluid of attractive-well diameter λffσff=1.5 in the presence of a homogeneous surface modeled by the square-well potential of attractive well from 0.8σff to 1.8σff. We investigate surface phase coexistence of thin-thick film transition using grand-canonical transition matrix Monte Carlo (GC-TMMC) and histogram reweighting techniques. Molecular dynamics (MD) and GC-TMMC are utilized to predict the properties of the fluid for various surface fluid affinities. Occurrences of prewetting transition with the variation of surface affinity are observed for a domain of reduced temperature from T*=0.62 to 0.75. We have used MD and GC-TMMC+finite size scaling (FSS) simulations to calculate the boundary tension as a function of temperature as well as surface affinity. Boundary tensions via MD and GC-TMMC+FSS methods are in good agreement. The boundary tension increases with the decrease of wall-fluid affinity. Prewetting critical properties are calculated using rectilinear diameter approach and scaling analysis. We found that critical temperature and density increase with the decrease of wall-fluid affinity.
Local dielectric spectroscopy of near-surface glassy polymer dynamics
Authors: Crider P. S. , Majewski M. R. , Zhang Jingyun , Oukris H. , Israeloff N. E.
Published: January 2008

A noncontact scanning probe microscopy method was used to probe local near-surface dielectric susceptibility and dielectric relaxation in polyvinyl acetate near the glass transition. Dielectric spectra were measured from 10−4to102Hz as a function of temperature. The measurements probed a 20nm thick layer below the free surface of a bulk film. A significant change in the fragility index and moderate narrowing of the distribution of relaxation times were found in the near-surface layer. In contrast to results for ultrathin films confined on or between metallic electrodes, no reduction in the dielectric strength was found, inconsistent with the immobilization of slower modes.
Magnetization reversal and microstructure of FePt–Ag (001) particulate thin films for perpendicular magnetic recording media
Authors: Wei D. H. , Yuan F. T. , Chang H. W. , You K. L. , Liou Y. , Yao Y. D. , Wu J. K.
Published: January 2008

FePt thin films with the addition of Ag layers have been fabricated in order to study the microstructure and magnetic properties via a molecular beam epitaxy technique on MgO (001) single-crystal substrates at 350°C. The enhancement of the coercivity is due to the film structures changed from continuous state to an isolated particulate character, not an ordering enhancement of FePt films with Ag addition. Studies of angular dependent coercivity show a tendency of a domain-wall motion shift toward rotation of reverse-domain type with the addition of Ag layers into the FePt films. The intergrain interaction was confirmed from the Kelly-Henkel plot that indicated FePt films with Ag addition can lead to the reduction of intergrain exchange coupling.
Design of a high-temperature and high-pressure liquid flow cell for x-ray absorption fine structure measurements under catalytic reaction conditions
Authors: Kawai Toshihide , Chun Wang-Jae , Asakura Kiyotaka , Koike Yuichiro , Nomura Masaharu , Bando Kyoko K. , Ted Oyama S. , Sumiya Hitoshi
Published: January 2008

The design and performance of a new high-pressure and high-temperature cell for measurement of x-ray absorption fine structure (XAFS) spectra of solid catalysts working in a flowing liquid are presented. The cell has flat, high-purity sintered cubic boron nitride (c-BN) windows which can tolerate high temperature (900K) and high pressure (10MPa). The c-BN is a new material which has the highest tensile strength, second only to diamond, and is also chemically and thermally stable. The use of the cell is demonstrated for measurements of PtPd∕Al2O3 and Ni2P∕SiO2 hydrodesulfurization catalysts at reaction conditions. A technique called delta χ (Δχ), involving determining the difference between XAFS spectra of the sample at reaction conditions and the bare sample, is introduced.
Uncertainty principle with quantum Fisher information
Authors: Andai Attila
Published: January 2008

In this paper we prove a lower bound for the determinant of the covariance matrix of quantum mechanical observables, which was conjectured by Gibilisco et al. and has the interpretation of uncertainty. The lower bound is given in terms of the commutator of the state and the observables and quantum Fisher information (generated by an operator monotone function).
Grain-boundary effects on magnetotransport properties in La2∕3Ca1∕3MnO3∕YBa1.8Eu0.2Cu3O7 multilayers
Authors: Zhang Y. M. , Wu X. S. , Ji Q. , Weng Y. Y. , Gao J. , Tan W. S. , Zhai Y.
Published: January 2008

La 2 ∕ 3 Ca 1 ∕ 3 Mn O 3 (LCMO)/YBa1.8Eu0.2Cu3O7 (YBECO) multilayers on yttrium-stabilized ZrO2 are fabricated. YBECO sublayer is well crystallized in c-axis orientation, while LCMO sublayer crystallized in (001) textured structure, which forms special mosaic structure. By magnetization measurements, we confirm that the cluster spin glass existed in LCMO/YBECO multilayers in low temperature, which may scatter the transport electrons. Superconductivity cannot be observed when thickness of YBECO layer is less than 24nm. The magnetoresistance ratio depends on the thickness of YBECO layer. The magnetotransport properties of the multilayers make it very promising to provide a technological support for the heterostructure and superlattice of manganites and superconductors.
On the magnetic properties of Gd implanted GaN
Authors: Hejtmánek J. , Knížek K. , Maryško M. , Jirák Z. , Sedmidubský D. , Sofer Z. , Peřina V. , Hardtdegen H. , Buchal C.
Published: January 2008

The wurzite type gallium nitride doped by gadolinium, Ga1−xGdxN (x∼0.01–0.07), was prepared by Gd ion implantation of the parent GaN thin films deposited on sapphire substrates. The material obtained exhibits a weak ferromagnetism (FM) persisting up to 700K. At higher Gd concentrations, the minute FM component coexists with much more pronounced Curie-type paramagnetism. In a dilute limit (x⩽0.01), the latter part is substantially reduced and the saturated FM moment reaches the value M∼2μB∕Gd atom.
Determination of the glass transition temperature of photorefractive polymer composites from photoconductivity measurements
Authors: Quintana José A. , Boj Pedro G. , Villalvilla José M. , Díaz-García María A. , Ortiz Javier , Martín-Gomis Luis , Fernández-Lázaro Fernando , Sastre-Santos Ángela
Published: January 2008

A method to determine the glass transition temperature (Tg) of photorefractive (PR) polymer composites, based on photoconductivity measurements, is proposed. The composite Tg is identified as the temperature at which a clear change in slope in the Arrhenius plot representation of the photoconductivity is obtained. We demonstrate that for PR polymers, this method is more appropriate than the one generally used, based on differential scanning calorimetry (DSC). For PR composites based on the hole transporting polymer poly(N-vinylcarbazole), the Tg value determined from photoconductivity data is around 30°C higher than that obtained by DSC.