bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of the cytochrome P‐450 system inducers on the development of drosophila melanogaster
Authors: Fuchs S. Yu. , Spiegelman V. S. , Belitsky G. A.
Published: October 2006

D. melanogaster development was markedly retarded and its survival decreased by larvae treatment with compounds being strong inducers of the cytochrome P‐450 2B in mammals— phenobarbital (PB*), perfluorodecaline (PFD), transstilbene oxide (TSO), and triphenyldioxane (TPD). At the same time, the weak inducer hexobarbital or the selective cytochrome P‐450 inducer in mice but not in rats 1,4‐bis[2‐(dichloropyridyl‐oxy)]‐benzene (DPB) did not affect the larvae development. The cytochrome P‐450 1A1 inducers benzo(a)anthracene (BA) and β‐naphtoflavone (BNF) were also not effective. The toxicity of phenobarbital was shown to be decreased by the cytochrome P‐450 inhibitor piperonyl butoxide by adding 20‐hydroxyecdysone or by treatment with aminophylline—the indirect enhancer of ecdysone production in the larval prothoracic gland. The hypothesis of the moulting hormone degradation as the cause of elevated larvae mortality resulting from the induced high mixed function oxidase activity has been discussed.
Effects of piperine on enzyme activities and bioenergetic functions in isolated rat liver mitochondria and hepatocytes
Authors: Jamwal Deshvir S. , Singh Jaswant
Published: October 2006

The influence of piperine on the enzymes and bioenergetic functions in isolated rat liver mitochondria and hepatocytes was studied. Piperine at lower concentrations (<50 μM) did not affect the RCR and ADP:O ratios, state 4 and 3 respirations supported by site‐specific substrates, viz. glutamate + malate, succinate, and ascorbate + TMPD. The site‐specific effects became significantly apparent only at higher concentrations. Only the state 3 respiration supported by NAD‐linked substrates was impaired equipotently in mitochondria and permeabilized hepatocytes; the effect appeared to be localized at energy‐coupling site 1. In hypotonic treated mitochondria, respiration supported by three kinds of substrates was not affected.

Among the respiratory chain‐linked enzymes, the activity of NADH‐dehydrogenase registered a significant decrease of about 25, 42, and 53% at 100, 150, and 180 μM piperine, respectively. The activity of Mg++‐ATPase, however, was stimulated at concentrations above 150 μM. Among the matrix enzymes, only malate and succinate dehydrogen‐ases were studied. Malate dehydrogenase only showed a strong concentration‐related inhibition in both the forward and backward directions. Enzyme kinetics indicated noncompetitive inhibition with a very low Ki of 10 μM. The presence of unsaturated double bonds in the side chain of piperine appeared essential for producing this strong inhibition. The studies suggested that piperine produces concentration related site‐specific effects on mitochondrial bioenergetics and enzymes of energy metabolism.
Controversial role of intracellular iron in the mechanisms of chemically‐induced hepatotoxicity
Authors: Badr Mostafa Z.
Published: October 2006

Hepatotoxicity induced by various therapeutic agents, industrial chemicals and environmental pollutants is a well‐recognized phenomenon. These chemicals are known to cause liver damage that is localized to either periportal or centrilobular regions of the liver lobule (1–3). Depending on dose, duration, and route of exposure, the resultant liver injury may regress or progress and becomes irreversible (1). Mechanisms involved in this selective, localized toxicity have been the target of extensive research efforts, and many Studies produced conflicting results. As depicted in Figure 1, although many investigators implicate iron and lipid peroxidation in this process (4‐9), others dispute such assertions (10–12).
Ozone increases amino‐ and carboxy‐terminal atrial natriuretic factor prohormone peptides in lung, heart, and circulation
Authors: Vesely David L. , Giordano Amy T. , Raska‐Emery Patricia , Montgomery Mark R.
Published: October 2006

Ozone can cause pulmonary edema and simultaneously decrease blood pressure. Atrial natriuretic peptides may mediate both of these effects in that they increase pulmonary capillary permeability resulting in edema formation and are potent vasodilating peptides. To examine this possibility, the lungs of Fischer 344 rats were exposed to ozone (0.5 ppm) for 8 hours which resulted in a three‐ to fourfold increase in atrial natriuretic peptides. Ozone also increased atrial natriuretic peptides in the heart two‐ to fivefold from 266 ± 25, 226 ± 22, and 288 ± 40 ng/g (room air) to 716 ± 26, 471 ± 14, and 1473 ± 235 ng/g recognized by the proANFs 1–30 and 31–67 and atrial natriuretic factor radioimmunoassays, respectively. Ozone also doubled the concentrations of proANFs 1–30, 31–67, and 1–98 and ANF in the circulation. This study demonstrates that ozone increases atrial natriuretic peptides within the heart, lung, and circulation, suggesting that atrial natriuretic peptides may mediate the decreased blood pressure and pulmonary edema observed with ozone exposure. Since the proANF 31–67 radioimmunoassay exclusively recognizes the ANF prohormone within the heart, this study further indicates that ozone can increase the synthesis of the ANF prohormone.
Long‐lasting effects of chronic ethanol administration on the activity of antioxidant enzymes
Authors: Almeida Vǎnia D' , Monteiro Maristela Goldnadel , Oliveira Maria Gabriela M. , Pomarico Ana Cristina , Bueno Orlando Francisco Amodeo , da Silva‐Fernandes Maria Eugěnia
Published: October 2006

The aim of this study was to investigate the long‐lasting effects of prolonged administration of ethanol doses on oxidative processes of aged rats. We determined the activity of superox‐ide dismutase (SOD), catalase (CAT), and gluta‐thione peroxidase (GPx) in erythrocytes of rats 15, 20, and 24 months old treated with an average daily dose of 1.5 g/Kg of ethanol or saline administered intraperitoneally for 13 weeks and after a 2 month period of withdrawal from treatment. The activity of all three enzymes decreased significantly with aging in the controls, while no age‐related changes were found among treated rats. These findings are important since they are the first to show a long‐lasting toxic effect of low ethanol doses observed in association with the aging process.
The effects of ricin on the sympathetic vascular neuroeffector system of the rabbit
Authors: Christiansen Victoria J. , Hsu Chia‐Hsuh , Robinson Casey P.
Published: October 2006

Ricin is a toxic lectin that inhibits protein synthesis. Because ricin decreases arterial pressure and causes cardiovascular collapse, its effects on the vascular neuroeffector system were investigated. Rabbits were given either of two doses of ricin, and then norepinephrine (NE) release from aorta to transmural stimulation, NE uptake into aorta, NE content of aorta, monoamine oxidase activity, and catechol‐O‐methyl transferase activity in aorta were determined 18 hours, 4 days or 7 days later. Norepinephrine uptake and enzyme activities in the aorta were not altered by ricin administration. Norepinephrine release and content of aorta were increased at most time periods following ricin administration, significantly so for NE content at 4 days and for release at 18 hours following the lower dose of ricin. We conclude that the mechanisms involved in the release of NE from sympathetic nerves in the vasculature are not impaired by ricin administration, but rather show changes that indicate increased compensatory activity.
A kinetic analysis of hepatic microsomal activation of parathion and chlorpyrifos in control and phenobarbital‐treated rats
Authors: Ma Tangeng , Chambers Janice E.
Published: October 2006

A kinetic analysis of cytochrome P450‐mediated desulfuration (activation) or dearylation (detoxication) showed that rat hepatic microsomes have a greater capacity to detoxify and a lower capacity to activate chlorpyrifos compared to parathion. Kinetic curves for the desulfuration of both parathion and chlorpyrifos were biphasic; K s of 0.23 and 71.3 μM were calculated for parathion, and 1.64 and 50.4 μM for chlorpyrifos. While phenobarbital (PB) exposure seemed to generally lower the Kmapp s for desulfuration except for the low Km activity on chlorpyrifos, the results were not statistically significant. While the low Km activity contributed 44 and 60% of the control Vmax for parathion and chlorpyrifos, respectively, it contributed 50 and 17% in PB‐treated rats. These studies have indicated the presence of a low Km activity capable of functioning at very low substrate concentrations. A single dearylation K was calculated, 56.0 and 9.8 μM for parathion and chlorpyrifos, respectively. Phenobarbital exposure seemed to raise the Ks of dearylation; however, again, the results were not statistically significant. While numerous biochemical factors contribute to the overall toxicity levels of phosphorothionate insecticides, the in vitro efficiencies of hepatic microsomal desulfuration and dearylation of parathion and chlorpyrifos correspond to the acute toxicity levels.
Effect of thyroid hormone administration on the depletion of circulating glutathione in the isolated perfused rat liver and its relationship to basolateral γ‐glutamyltransferase activity
Authors: Videla Luis A. , Fernández Virginia
Published: October 2006

The influence of thyroid hormone administration on liver glutathione (GSH) extraction in the isolated perfused liver was studied in fed rats for a period of 1–7 days following a single dose of 0.1 mg 3,5,3′‐triiodothyronine (T3)/kg. T3 treatment led to an early and transient calorigenic response, as well as an enhancement in liver GSH removal, reaching a maximal effect at 2 days after hormone administration, which was normalized in the 3‐ to 7‐day period studied. Addition of the γ‐glutamyltransferase (γ‐GT) inhibitor DL‐serineborate (4 mM) to the perfusate abolished the increase in the hepatic removal of GSH elicited by T3, and enhanced the sinusoidal concentration of GSH, studied at 2 days after hormone administration. These data support the role of hepatic basolateral γ‐GT ectoactivity in the depletion of portally added and liver‐derived GSH as an adaptive response to recover GSH levels after reduction by T3‐induced oxidative stress.
Ah receptor involvement in mediation of pyruvate carboxylase levels and activity in mice given 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin
Authors: Ryu Byung‐Woo , Roy Shukla , Sparrow Barney R. , Selivonchick Daniel P. , Schaup Henry W.
Published: October 2006

The arylhydrocarbon receptor (AhR) plays a central role in mediating 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD) toxicity in animals. The investigations described here provide evidence that support a role for the AhR in TCDD‐mediated pyruvate carboxylase (PC) level/activity reductions in mice. Pyruvate carboxylase plays a pivotal role in gluconeogenesis and in supplying carbon units for the citric acid cycle. Delivered ip in a corn oil carrier, TCDD suppresses PC activity/amount at doses as low as 1 μg/kg in responsive C57BL/6J(Ahb/b) mice. Corn oil alone injected ip into mice at 4 mL/kg appears to be an inducer that increases the amount and activity of PC. However, TCDD suppresses this induction. In the Ahb/b mouse, PC levels and activity are reduced to 10% of control values at a dose of 75 μg/kg. A time‐course experiment shows that the PC reductions are apparent within 16 hours post‐TCDD exposure. Here we report investigations on the PC/TCDD response using a congenic C57BL/6J(Ahd/d) mouse strain having an AhR with a low affinity for TCDD. If the PC/TCDD response is AhR mediated, the congenic mouse strain (Ahd/d) would require much higher doses of TCDD to suppress PC. In the Ahd/d mice, we observe that an approximately 60‐fold increase in TCDD dose is necessary to produce a PC/TCDD effect. We also find that in Ahd/d mice, corn oil does not induce an increase in PC activity/amounts, as reported for Ahb/b mice.
Paradoxical effect of sudan III on the in vivo and in vitro genotoxicity elicited by 7,12‐dimethylbenz(a)anthracene
Authors: Hatakeyama Shigeki , Hayasaki Yayoi , Masuda Makihiko , Kazusaka Akio , Fujita Shoichi
Published: October 2006

Effect of the induction of drug metabolizing enzymes by Sudan III on the in vivo and in vitro genotoxicity elicited by 7,12‐dimethyl‐benz(a)anthracene (DMBA) was investigated. A significant suppression of DMBA‐induced micronucleated reticulocytes was observed in C57BL/6 mice treated with Sudan III intraperitoneally for 3 or 5 days before injection of the DMBA. However, the preincubation of DMBA with hepatic microsomes from Sudan III‐treated rats caused a marked increase in the in vitro mutagenicity in the Ames assay, paradoxically. Sudan III was found to induce CYP 1A1, 7‐ethoxycoumarin O‐deethylase activity as well as both UDP‐glucuronyl transferase and glutathione S‐transferase activities. The increase of mutagenicity of DMBA observed in the Ames assay using hepatic microsomes from Sudan III‐treated rats was inhibited by the addition of uridine 5′‐diphosphoglucuronic add or reduced glutathione with cytosol. Mutagenic metabolites of DMBA formed by CYP1A1 appeared to be effectively detoxified by these phase II enzymes.

The results of this study suggest that Sudan III‐induced prevention of in vivo mutagenesis is due to the induction of both CYP 1A1 and detoxifying phase II enzymes. The induced CYP1A1 may accelerate formation of active metabolic intermediates, but phase II enzymes are also induced and detoxify these intermediates to inactive metabolites. This would reduce residence time of the carcinogen in the body and the time of exposure to active metabolites for target organs.
Alteration of Ca2+ homeostasis of sea urchin embryos by retinoid CD 367, dual effect on egg cleavage and embryonic development
Authors: Espagnet S. , Delescluse C. , Pesando D. , Graillet C. , Michel S. , Girard J.‐P.
Published: October 2006

The effect of a light stable retinoid (CD 367) was studied on sea urchin embryos. CD 367 did not affect sperm‐egg interaction. In a range of concentrations between 10 and 100 μM, CD 367 delayed the first and the second cleavages. When added after fertilization, micromolar amounts of CD 367 delayed hatching and produced embryonic abnormalities in a dose‐dependent manner. Mesodermal cells, primary (PMC) and secondary (SMC) mesenchyme cells migration was particularly disturbed, leading to exogastrulations and calcified spicules malformations. Concentrations of CD 367 higher than 8 μM were embryolethal. Micromolar amount of CD 367 increased plasmalemma Ca2+ permeability of fertilized eggs but not of unfertilized eggs. CD 367 inhibited ATP‐dependent intra‐cellular sequestration of Ca2+ in a range of concentrations similar to those affecting egg cleavage and embryonic structures. Since we were unable to detect nuclear receptors for CD 367 in sea urchin eggs and ovocytes, these effects probably are not related to interaction of the retinoid with members of the RAR family, to which CD 367 has a high affinity, but rather to its toxicity by the means of some unknown mechanisms.
Altered glycine transport by cerebral tissue and decreased Na+ and Ca++ pump activities during organophosphorus‐ester–induced delayed neurotoxicity development period
Authors: Sharma Shri Krishna , Bhattacharya Bijoy K.
Published: October 2006

Uptake of [U‐14C] glycine during the organophosphorus‐ester‐induced delayed neurotoxicity (OPIDN) development period was studied. Diisopropyl fluorophosphate (DFP), a delayed neurotoxic organophosphorus ester was administered to adult rats and hens. Results showed a decreased accumulation of glycine in hen cerebral cortex slices during the delayed neurotoxicity development period. An altered sensitivity toward transport inhibitors 2,4‐dinitrophenol and ouabain was observed in DFP‐treated hens. An altered neuronal membrane function during the OPIDN development period is reported in the present work. Brain Na+, K+‐ATPase and Ca++‐ATPase activities decreased during the neurotoxicity development period. The decrease in Ca++‐ATPase activity persisted in hens until the complete development of neurotoxic symptoms. Decreased Ca++ pump activity is correlated with altered membrane function during OPIDN. © 1996 John Wiley & Sons, Inc.
The structure of anchovy outer retinae (Engraulididae, Clupeiformes) — A comparative light‐ and electron‐microscopic study using museum‐stored material
Authors: Heß Martin , Melzer Roland R. , Eser Roland , Smola Ulrich
Published: October 2006

The outer retinal architecture of Engraulididae is uncommon among vertebrates. In some anchovies, e.g., Anchoa, two cone types are arranged alternating in long photoreceptor chains, i.e., polycones. The cones have radially oriented outer segment lamellae in close contact with a complex guanine tapetum, most probably subserving polarization contrast vision. To clarify the distribution of the aberrant polycone architecture within the Engraulididae and to provide indications about polycone evolution, the outer retina morphology of 16 clupeoid species was investigated by light and electron microscopy, predominantly using museum‐stored material. The outgroup representatives of four clupeid subfamilies (Clupeonella cultriventris, Dorosoma cepedianum, Ethmalosa fimbriata, Pellonula leonensis) show a row pattern of double cones, partially with single cones at defined positions and a pigment epithelium with lobopodial protrusions containing melanin. The pristigasterid Ilisha africana has double rows of single cones lying between linear curtains of pigment epithelium processes filled with minute crystallites and melanin concentrated near their vitreal tips. Within the Engraulididae, two main architectures are found: Coilia nasus and Thryssa setirostris have linear multiple cones or polycones separated by long pigment epithelium barriers containing tapetal crystallites and melanin in the tips (also found in Setipinna taty), whereas Anchoviella alleni, Encrasicholina heteroloba, Engraulis encrasicolus, Engraulis mordax, Lycengraulis batesii, and Stolephorus indicus exhibit the typical polycone architecture. Cetengraulis mysticetus and Lycothrissa crocodilus show cone patterns and pigment epithelium morphology differing from the other anchovy species. The sets of characters are compared, corroborated with the previous knowledge on clupeoid retinae and discussed in terms of functional morphology and visual ecology. A scenario on polycone evolution is developed that may serve as an aid for the reconstruction of engraulidid phylogeny. Furthermore, this study demonstrates the suitability of museum material for morphological studies, even at the electron microscopic level. J. Morphol., 2006. © 2006 Wiley‐Liss, Inc.
Dual‐bolus approach to quantitative measurement of pulmonary perfusion by contrast‐enhanced MRI
Authors: Risse Frank , Semmler Wolfhard , Kauczor Hans‐Ulrich , Fink Christian
Published: October 2006

Purpose

To evaluate a dual‐bolus approach to pulmonary perfusion MRI.

Materials and Methods

The dual‐bolus approach uses a separate low‐dose measurement for the arterial input function (AIF) to ensure linearity. The measured AIF is constructed according to a subsequent higher dose used for the tissue concentration curves in the lung. In this study a prebolus of 0.01 mmol/kg followed by doses of 0.04 mmol/kg and 0.08 mmol/kg was used. Measurements were performed using time‐resolved two‐dimensional fast low‐angle shot (2D FLASH) MRI (TE/TR = 0.73 msec/1.73 msec; flip angle = 40°; generalized autocalibrating partially parallel acquisitions (GRAPPA) factor = 3; temporal resolution = 400 msec) in end‐inspiratory breath‐hold.

Results

The combination of prebolus/0.04 mmol/kg resulted in a pulmonary blood flow (PBF) of 211 ± 77 mL/min/100 mL, and a pulmonary blood volume (PBV) of 20 ± 3 mL/100 mL. The combination of prebolus/0.08 mmol/kg resulted in approximately 50% lower perfusion values, most likely due to saturation effects in the lung tissue.

Conclusion

A dual‐bolus approach to pulmonary perfusion MRI is feasible and may reduce the problem of lacking linear relationship between the contrast‐agent concentration and signal intensity. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Renal perfusion: Comparison of saturation‐recovery TurboFLASH measurements at 1.5T with saturation‐recovery TurboFLASH and time‐resolved echo‐shared angiographic technique (TREAT) at 3.0T
Authors: Michaely Henrik J. , Nael Kambiz , Schoenberg Stefan O. , Finn J. Paul , Oesingmann Niels , Lodemann Klaus‐Peter , Reiser Maximilian F. , Ruehm Stefan G.
Published: October 2006

Purpose

To investigate the dependence of semiquantitative renal perfusion parameters on the acquisition technique and field strength used.

Materials and Methods

After intravenous injection of 7‐mL Gd‐chelates, high‐temporal‐resolution turbo fast low‐angle shot (TurboFLASH) renal perfusion measurements were performed on eight healthy volunteers at 1.5T and another eight healthy volunteers at 3.0T. Another eight healthy volunteers were examined at 3.0T using time‐resolved echo‐shared angiographic technique (TREAT) after bolus administration of 7‐mL Gd‐chelates with a temporal resolution of 1.4 seconds. Analysis of the first‐pass perfusion data yielded the following semiquantitative renal perfusion indices: mean transit time (MTT), time to peak (TTP), maximal upslope (MUS), and maximal signal intensity (MSI).

Results

MTT and TTP did not show significant differences between the different techniques. MSI and MUS were significantly (P ≤ 0.002) higher with TREAT (591.1 a.u./second and 103.5 a.u./second) than with TurboFLASH at both field strengths (1.5T: 400.5 a.u./second and 65.4 a.u./second; 3.0T: 362.2 a.u./second and 68.7 a.u./second).

Conclusion

Semiquantitative renal perfusion measurements are feasible with time‐resolved echo‐shared sequences and TurboFLASH techniques. While MTT and TTP appear to be independent of the technique and field strength applied, MUS and MSI are higher with TREAT. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Effect of neurosphere size on the growth rate of human neural stem/progenitor cells
Authors: Mori Hideki , Ninomiya Kazuaki , Kino‐oka Masahiro , Shofuda Tomoko , Islam Mohammed Omedul , Yamasaki Mami , Okano Hideyuki , Taya Masahito , Kanemura Yonehiro
Published: October 2006

Neural stem/progenitor cells (NSPCs) proliferate as aggregates in vitro, but the mechanism of aggregation is not fully understood. Here, we report that aggregation promotes the proliferation of NSPCs. We found that the proliferation rate was linear and depended on the size of the aggregate; that is, the population doubling time of the NSPCs gradually decreased as the diameter approached 250 μm and flattened to a nearly constant value beyond this diameter. Given this finding, and with the intent of enhancing the efficiency of human NSPC expansion, we induced the NSPCs to form aggregates close to 250 μm in diameter quickly by culturing them in plates with U‐bottomed wells. The NSPCs formed aggregates effectively in the U‐bottomed wells, with cell numbers approximately 1.5 times greater than those in the aggregates that formed spontaneously in flat‐bottomed wells. In addition, this effect of aggregation involved cell–cell signaling molecules of the Notch1 pathway. In the U‐bottomed wells, Hes1 and Hes5, which are target genes of the Notch signal, were expressed at higher levels than in the control, flat‐bottomed wells. The amount of cleaved Notch1 was also higher in the cells cultured in the U‐bottomed wells. The addition of γ‐secretase inhibitor, which blocks Notch signaling, suppressed cell proliferation in the U‐bottomed wells. These results suggest that the three‐dimensional architecture of NSPC aggregates would create a microenvironment that promotes the proliferation of human NSPCs. © 2006 Wiley‐Liss, Inc.
Managing change before change management
Authors: Greener Tony , Hughes Mark
Published: October 2006

This paper informs current practice about change management by looking back on how strategic change was managed in BL Cars in the late 1970s.

One of the co‐authors found himself at the heart of a major transformation effort in the company and was uniquely placed to witness how this change was managed in this now‐defunct car manufacturer.

This paper concludes that an appreciation of history may be beneficial both in terms of understanding strategic change and the practice of managing strategic change.

Copyright © 2006 John Wiley & Sons, Ltd.
Toward a unified retrieval outcome analysis framework for cross‐language information retrieval
Authors: Chen Jiangping
Published: October 2006

This paper proposes a Retrieval Outcome Analysis Framework, or ROA Framework, to systematically evaluate retrieval performance of Cross‐Language Information Retrieval systems. The ROA framework goes beyond TREC‐type retrieval evaluation methodology by including procedures focusing on individual queries, especially difficult queries. The framework is comprised of four interrelated components: (1) Overall System Performance Evaluation, (2) Query Categorization, (3) Translation Analysis, and (4) Individual Query Analysis. An example of applying the framework is discussed in detail. The author believes the proposed framework would be especially useful for the development of real‐world Cross‐Language Information Retrieval systems because the evaluation guided by the framework has the potential to discover causes behind poor retrieval performance.
How the overlap between the search results of different retrieval systems correlates with document relevance
Authors: Spoerri Anselm
Published: October 2006

This paper provides an analysis of the overlap between the search results of retrieval systems that participated in TREC 3, 6, 7 and 8 to provide empirical support for some of the key assumptions guiding the design of data fusion methods. It shows that the potential relevance of a document increases exponentially as the number of search methods retrieving it increases — called the Authority Effect. It also shows that documents higher up in ranked lists and found by more systems are more likely to be relevant — called the Ranking Effect. Both effects can help explain why major data fusion methods perform well.
Towards a research agenda for visual informatics
Authors: Jörgensen Corinne , Fast Karl , von Eberstein Alison , Fleischmann Kenneth R. , Jörgensen Peter
Published: October 2006

“Visual Informatics” currently refers to visualization of and interaction with very large data sets, including both text and numeric data, chemical and molecular structures, and genome sequences. As such, it follows the widespread definition of “informatics” as being “the study of the application of computer and statistical techniques to the management of information,” or, more popularly, “computer science + X.” Commercially available visual informatics software, (such as Logical Images' VisualDx) provides real‐time visual decision support for such things as diagnosis of disease. This panel suggests reorienting the concept of informatics towards the human processes that are facilitated by technology. Along these lines, it proposes a broader definition and refocusing of the concept of visual informatics and explores the expansion of the range of research which visual informatics can address. It also looks beyond visual informatics to the larger concept of “media informatics” where information and communication technologies expand to include multiple modalities of interaction within systems, organizations, and cultures.

In keeping with the conference theme of synergies between research and practice, this panel will explore a research agenda grounded through the optics of both current “real world” applications being developed in research and industry and theoretical approaches which can enfold these projects within rich conceptual frameworks.

The panel format will consist of a brief introduction to the topic by the moderator, followed by several presentations exploring these issues, followed by a summation and discussion. A unique aspect of this panel is that the dialogue among the presenters and their audience will begin well before the conference, through the mechanism of the ASIS&T SIGVIS weblog (http://informationvisualization.typepad.com). We encourage participants to review the weblog and add their comments to the entries.
One and three limit cycles in a cubic predator–prey system
Authors: Huang Xuncheng , Wang Yuanming , Zhu Lemin
Published: October 2006

A cubic differential system is proposed, which can be considered a generalization of the predator–prey models, studied recently by many authors. The properties of the equilibrium points, the existence of a uniqueness limit cycle, and the conditions for three limit cycles are investigated. The criterion is easy to apply in applications. Copyright © 2006 John Wiley & Sons, Ltd.
Analytical integrations and SIFs computation in 2D fracture mechanics
Authors: Salvadori A. , Gray L. J.
Published: October 2006

Analytical integrations, in the framework of linear elastic problems modelled by means of boundary integral equations, have been considered in a previous publication (Int. J. Numer. Methods Eng. 2002; 53(7):1695–1719): the present note aims at extending the subject to linear elastic fracture mechanics. In such a context, special shape functions have been recently proposed (SIAM J. Appl. Math. 1998; 58: 428–455) in order to increase accuracy in stress intensity factors approximation: the closed form solution for ‘integrals’ that arise from the boundary element method is a goal of the present work. Exploiting the analytical integrations, asymptotical analysis around the crack tip are made possible, with the purpose of formulating a coherent and accurate correlation between approximated stress intensity factors and crack opening displacements over the crack tip straight special elements. Copyright © 2006 John Wiley & Sons, Ltd.
The amino acid sequence of toxin IV from the Androctonus australis scorpion: Differing effects of natural mutations in scorpion α‐toxins on their antigenic and toxic properties
Authors: Mansuelle Pascal , Martin Marie‐France , Rochat Hervé , Granier Claude
Published: October 2006

The complete amino acid sequence (64 residues) of the AaH IV toxin from the scorpion Androctonus australis Hector was determined by automated Edman degradation and was compared with the sequences of other Androctonus toxins. AaH IV was also tested by radioimmunoassay for binding to antisera raised against other toxins of the same species. The results indicated that AaH IV shares some of the antigenic properties of AaH I and AaH III toxins, but does not cross‐react with anti‐AaH II antibodies. The structural basis for the observed antigenic relationships can be found in the high degree of homology displayed by AaH IV with regard to AaH I and III, the changes in amino acid residues equally affecting regions included or excluded from the main predicted antigenic sites of AaH IV. The lower biological potency of AaH IV is presumably the result of some of the sequence differences. In particular, substitution affecting the charge and bulkiness of residue 61 could account for the poor receptor binding and consequential weak toxic properties of this molecule. © 1992 Wiley‐Liss, Inc.
Novel study on the elicitation of hypersensitive response by polyunsaturated fatty acids in potato tuber
Authors: Fanelli Corrado , Castoria Raffaello , Fabbri Anna Adele , Passi Siro
Published: October 2006

A GC‐MS procedure was carried out for the simultaneous and unequivocal quantitation of both potato phytoalexin (rishitin and lubimin) accumulation and the rate of disappearance of polyunsaturated fatty acids (PUFA) and some of their esters tested as possible elicitors. Potato 5‐lipoxygenase and lipolytic acyl hydrolase play a key role in hypersensitive response (HR) induction. As expected, arachidonic acid, its hydrolysable esters, and eicosapentaenoic acid elicited much higher HR than the other PUFA tested, although the latter were equally affected by potato 5‐lipoxygenase. Hydroxyl radicals appear to be actively involved in the browning process. The polyaminoacid poly‐L‐lysine did not show any eliciting activity. © 1992 Wiley‐Liss, Inc.
Purification of staphylococcal enterotoxin E
Authors: Brehm Rossalyn D. , Tranter Howard S.
Published: October 2006

Staphylococcal enterotoxin E has been purified by a combination of Red‐A ligand chromatography and Mono‐S (cation – exchange) chromatography. Commencing with 30 litres of fermenter‐grown culture the method has been used to purify 17 mg of toxin, giving a purification yield of around 40%. The purity of the toxin was over 98% when analysed by sodium dodecyl sulphate‐polyacrylamide gel electrophoresis, but demonstrated three isoelectric forms by isoelectric focusing, with pl values of 7.6, 7.4, and 7.0. This method adds to the versatility of the Red‐A matrix system which can also be used for the purification of staphylococcal enterotoxins A, B, and C2. © 1992 Wiley‐Liss, Inc.
Effects of purified Clostridium difficile toxin A in the small intestine of the rat in vivo
Authors: Beubler Eckhard , Schirgi‐Degen Andrea , Pabst Maria Anna , Pothoulakis Charalabos , LaMont J. Thomas
Published: October 2006

The action of highly purified Clostridium difficile toxin A was studied in the jejunum of rats in vivo. C. difficile toxin A reversed dose‐dependently net fluid absorption into net fluid secretion, accompanied by an increase in prostaglandin E2 but not 5‐hydroxytryptamine output into the gut lumen. Accordingly, indomethacin but not the 5‐hydroxytryptamine receptor antagonists ketanserin plus tropisetron were able to inhibit toxin A‐induced fluid secretion. Atropine and hexamethonium were without effect on the action of toxin A, such excluding a nervous mechanism. The cyclic nucleotides cyclic AMP and cyclic GMP appear not to be involved in the mediation of the secretory response. The reduced cyclic GMP levels are most likely the result of a complete destruction of the villus membranes, where the guanylate cyclase is located. Histological studies revealed massive damage to intestinal villi, whereas the majority of the crypts seem to be unaffected. In conclusion, toxin A‐induced intestinal fluid secretion appears to be caused mainly by severe mucosal damage. PGE2‐release may be the consequence of the inflammation accompanying this damage. The mechanism seems to be completely different to those of cholera toxin or Escherichia coli heat stable enterotoxin. © 1992 Wiley‐Liss, Inc.
Alteration in the tissue retention of [14C]‐caffeine in pregnant mice by dimethylsulfoxide
Authors: Gross Sandra M. , Reddy Rajasekhar V. , Reddy Chada S.
Published: October 2006

This study was undertaken to investigate if dimethylsulfoxide (DMSO)‐induced potentiation of maternal toxicity and teratogenicity of caffeine (CA) is mediated by DMSO‐induced alteration of CA levels in maternal and fetal tissues. Pregnant CD 1 mice were given single dose of [14C]‐caffeine intraperitoneally (i.p.) on gestational day 12, in distilled water (DW) or 20% (v/v) solution of DMSO in DW. At 6, 12, and 24 hr following dosing, radioactivity in various maternal and fetal tissues was compared. Significantly (p ⩽ 0.05) higher CA‐derived radioactivity was seen in maternal brain, carcass and heart as well as placenta and fetal heads and bodies 6 hr after dosing with CA in DMSO compared to CA in DW. A concomittant reduction in urinary excretion of CA‐derived radioactivity in DMSO group or compared to CA in DW was observed at this time. At 12 hr following dosing, significantly (P ⩽ 0.05) higher CA‐derived radioactivity was noted in maternal heart, brain, and carcass; placenta; and fetal bodies in mice receiving CA in DMSO compared to those receiving CA in DW. These results suggest that increased accumulation of CA in certain maternal and fetal tissues could contribute to the observed increase in maternal and fetal toxicity of CA by DMSO. © 1992 Wiley‐Liss, Inc.
Purification from Vipera lebetina (desert adder) venom of a protein that depletes human complement
Authors: Gasmi Ammar , Louzir Hechmi , Karoui Habib , Ayeb Mohamed El , Dellagi Koussey
Published: October 2006

A rapid and efficient procedure for purification from Vipera lebetina venom of a low molecular weight anticomplement protein is described. The procedure used gel filtration on Superose 12, followed by ion‐exchange chromatography on a Mono Q column. The purified protein migrated on SDS‐PAGE as a single band of about 25,000 Da under nonreducing conditions and as a band of 16,000 Da under reducing conditions. Its isoelectric point was estimated to be 7.6 ± 0.1. The isolated Vipera lebetina protein was found to decrease the hemolytic activity in human serum measured by assays for classical pathway and alternative pathway activation. The loss of the complement activity could be ascribed, at least in part, to a proteolytic cleavage of the a chains of C3 and C4. This protein was also found to be without action on human blood coagulation and on purified fibrinogen and Factor B. © 1994 wiley‐Liss, Inc.
Isolation and identification of two potent neurotoxins, aspartic acid and glutamic acid, from yellow star thistle (Centaurea solstitialis)
Authors: Roy Dwijendra N. , Peyton David H. , Spencer Peter S.
Published: October 2006

Horses grazins for prolonged periods on yellow star thistle (YST), a plant which grows wild in western parts of the United States, develop an extrapyramidal disorder known as nigropallidal encephalomalacia (NPE). Attempts have been made to identify, isolate, and characterize the toxins responsible for the disease in animals. Using the organotypic tissue culture system on mouse cortical explants as a specific assay method for neurotoxicological evaluation, it has been possible to isolate and characterize two potent neuroexcitotoxic compounds, aspartic and glutamic acids, the former being the major toxic component in the alcoholic extract of the plant. There is also evidence that other neurotoxic compounds are present in the extract. The detailed procedure for isolation and characterization of these compounds is given here. © 1995 Wiley‐Liss, Inc.
Directly toxic effects of plant chemicals which may occur in human and animal foods
Authors: Seawright Alan A.
Published: October 2006

Pyrrolizidine alkaloids are among the most significant plant chemicals causing disease in animals and humans. After absorption from the gut, the compounds are converted to electrophilic pyrroles in the liver which, apart from causing damage to this organ, may escape to cause injury to extraheptic tissues such as the lungs, heart, and kidneys.

A group of compounds more recently found to be associated with neurotoxicity are various polyhydroxyalkaloids which are able to interfere with polysaccharide metabolism. They are able to inhibit lysosomal monosaccharidases by virtue of their structural resemblance to the transition state of particular sugar molecules. The resulting lysosomal storage diseases have pathology identical to that of the respective congenital and heritable lysosomal storage diseases which occur in animals and humans.

Consumption of cycad plants by cattle may cause a neurotoxicity characterised mainly by a posterior sensory ataxia. In recent years, cycads are considered to be a risk factor for a spectrum of progressive neuro degenerative diseases of humans in the Western Pacific region. The known toxins in the plant are the methylazoxymethanol glycosides which are hepatotoxic and carcinogenic, and the neurotoxic non‐protein amino acid β‐methylaminoalanine.

A plant carcinogen which can be of great abundance in the nutritional environment is the illudine norsesquiterpene glucoside ptaquiloside which is found in bracken fern. This is the only plant carcinogen which causes natural outbreaks of bladder and/or intestinal cancer in livestock.

Many legumes contain phytooestrogens, notably isoflavones. Consumption of these compounds at high levels by sheep can cause extensive lesions of the genitalia of females and castrated males. A chronic long‐term effect of excessive oestrogen intake in ewes is “masculinization” of the internal genitalia leading to reduced fertility. The presence of such compounds in the diet may be associated with reproductive disorders in man. © 1995 Wiley‐Liss, Inc.
Design of sampling plans for mycotoxins in foods and feeds
Authors: Coker Raymond D. , Nagler Martin J. , Blunden Gerald , Sharkey Angela J. , Defize Peter R. , Derksen Giljam B. , Whitaker Thomas B.
Published: October 2006

The control of the occurrence of mycotoxins in foods and feeds requires effective surveillance and quality control procedures which facilitate the identification and control of the mycotoxin problem respectively.

Surveillance and quality control procedures involve a sequence of sampling, sample preparation, and analysis steps; and the integrity of the data produced by these procedures will be determined by the effectiveness of these steps.

It is imperative that the sampling step is performed as accurately as possible so that the sample collected is representative of the batch of food or feed under investigation. Needless to say, the collection of a biased sample will completely invalidate the resultant analytical data.

Most attempts to develop effective sampling protocols have focused upon the aflatoxins, since the majority of current regulations are concerned specifically with this group of mycotoxins. However, the design of effective sampling protocols has been severely hindered by the highly skewed distribution of the aflatoxins in foods and feeds.

Studies already performed indicate that representative samples of commodities composed of large particles (e.g., com and oilseed kernels) should be 10 kg in weight, at least, and composed of approximately one hundred incremental samples. Similar studies have indicated that samples of oilseed cakes and meal, however, should be composed of fifty incremental samples which afford a composite sample of approximately 5 kg in weight. Published 1995 Wiley‐Liss.
Anticholinergic anti‐Parkinson drug prescription in haloperidol‐treated patients: A population‐based study
Authors: Diana Giovanni , Alegiani Stefania Spila , Fortini Marco , Roberto  , Raschetti Roberto
Published: October 2006

Anticholinergic anti‐Parkinson drugs are often used to prevent or treat neuroleptic‐induced extrapyramidal side effects. National Health Service prescriptions for these drugs and haloperidol delivered in the geographical area of Rome, Italy, and the surrounding province (about 3,750,000 inhabitants) from 1986 to 1989 were reviewed. Individual prescription histories were reconstructed and analysed with a computerized procedure. Over the four years 1121 (32.2%) of the 3478 haloperidol‐treated individuals studied were concurrently prescribed anticholinergic anti‐Parkinson drugs. Their distribution shows an age‐related decrease, the percentage ranging from 50.7 (age 16–27) to 17.7 (ages over 80). The analysis of results by logistic regression also demonstrates that the probability of receiving anticholinergic anti‐Parkinson medication is higher in women and correlates with the amount of haloperidol prescribed.
Fluoxetine and suicide: Meta‐analysis and Monte‐Carlo simulations
Authors: Wan Po A. Li
Published: October 2006

Objective: To test the validity of the conclusion of a recent meta‐analysis1 of the possible association between fluoxetine and suicidal acts. Design: Monte‐Carlo simulations of the number of suicidal acts in clinical trials of the sizes reported in the published meta‐analysis.1 Main outcome measures: Simulated incidence of suicidal acts using binomial distributions with parameters equal to or higher than those reported in earlier papers. A pooled risk difference and the associated 95% confidence interval were calculated for each set of simulated data. Results: Assuming a true incidence of 0.3% of suicidal acts in patients receiving fluoxetine and 0.2% in patients receiving placebo, none of 30 sets of simulations showed a significant difference as judged by the pooled risk differences and the corresponding 95% confidence intervals. Even when the risk of suicidal acts was increased to 0.6%, only 38 of 100 simulations produced significant differences in the expected direction. Of the other 62 sets, 56 produced a non‐significant positive risk difference and six produced a non‐significant negative risk difference. Conclusion: The Monte‐Carlo simulations show that the meta‐analysis which claimed to demonstrate that the available data do not show that fluoxetine is associated with an increased risk of suicidal acts, was of low power. Much larger studies are needed before one can say categorically that fluoxetine is not associated with a higher incidence of suicidal acts than placebo. Conversely, the data to date (as the recent meta‐analysis rightly claim) also fail to demonstrate that the risk of suicidal acts is higher with fluoxetine than with placebo.
Inhibition of protein kinase CK2 leads to a modulation of androgen receptor dependent transcription in prostate cancer cells
Authors: Götz Claudia , Bachmann Christa , Montenarh Mathias
Published: October 2006

BACKGROUND

The androgen receptor (AR) mediates the biological responses of androgens in the prostate gland. In prostate cancer, this pathway is often deregulated and causes an uncontrolled proliferation.

METHODS

The current study focuses on the effects of an inhibition of protein kinase CK2 on the AR‐mediated transcription in LNCaP prostate cancer cells. We used chemical inhibitors of CK2 as well as dominant‐negative kinase mutants to downregulate the CK2 activity. We determined the effects of the inhibition by Western blot analysis of endogenous target genes of the AR as well as by reporter assays.

RESULTS

We found that inhibition of CK2 led to a downregulation of the AR‐dependent transcription. Moreover, the amount of the AR protein decreased significantly.

CONCLUSION

According to the fact that AR pathways are involved in the development and progression of prostate cancer, the ability to modulate AR function should provide an alternative basis for the development of new cancer therapies. Prostate © 2006 Wiley‐Liss, Inc.
Methodology for the generation and evaluation of safety system alternatives based on extended Hazop
Authors: Ramzan Naveed , Compart Fred , Witt Werner
Published: October 2006

Process safety is paramount in the secure and viable operation of any chemical process plant. Many techniques and methodologies have been defined over the years to undertake steps that will ensure a safe operating environment at a chemical facility. However, until now, process simulation has found very little or no use in safety‐related studies. This article introduces a systematic framework based on Extended Hazop (that is, Hazop supported by disturbance simulation related to process malfunctions.) The Extended Hazop differs from standard Hazop in documenting results, classification of frequency and consequences of process deviations, and application of a risk potential matrix (Hazop decision matrix). In this article, the Extended Hazop method is explained. Application of this method will be demonstrated in a separate article. © 2006 American Institute of Chemical Engineers Process Saf Prog, 2007
Molecular design of fullerene‐based ultralow‐k dielectrics
Authors: Wang Yuekui , Seifert Gotthard , Hermann Helmut
Published: October 2006

This paper presents results of a theoretical study of hypothetical insulating layers for semi‐conducting circuits. The dielectric material consists of C60 fullerenes interconnected by bridge molecules. The structural optimisation is carried out using quantum‐chemical methods. The predicted materials have ultralow values of the static dielectric constant of about k = 1.5 and good elastic bulk moduli of B = 12 to 17 GPa. These values meet the demands of future microelectronic devices. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)