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Various Classes (various + class)
Selected AbstractsInkjet Printing,Process and Its ApplicationsADVANCED MATERIALS, Issue 6 2010Madhusudan Singh Abstract In this Progress Report we provide an update on recent developments in inkjet printing technology and its applications, which include organic thin-film transistors, light-emitting diodes, solar cells, conductive structures, memory devices, sensors, and biological/pharmaceutical tasks. Various classes of materials and device types are in turn examined and an opinion is offered about the nature of the progress that has been achieved. [source] Assessment of estradiol and its metabolites in meatAPMIS, Issue 1 2001D. MAUME Most studies related to research on steroids in main edible tissues (muscle, liver or kidney) have focused on measurement of parent or major metabolite residues. In order to evaluate the estradiol content in bovine edible tissues, a multi-step extraction procedure was developed in conjunction with parallel metabolism studies of [14C],17,-estradiol in cattle (1,2). Various classes of free estradiol and conjugates were separated: estradiol ,17, and ,17,, estradiol-17-fatty acid esters, estradiol 17-glycoside, estradiol 3,glucuronide, estradiol,17-glycoside and 3- glucuronide (diconjugates) were separated. No sulphates conjugated forms have been found at the detection level of the method. The quantification was realized by calibration with deuterated 17, -estradiol -d3 standard and was validated at the ng kg,1 (ppt) level. Muscle, liver, kidney and fat samples from control or Revalor S® single (licensed implantation) or multi-implanted steers have been assayed. The results show a wide variation between animals, but both the highest value and the mean of total estradiol content in each group proportionally increase from untreated to multi-implanted animals. In accordance with international rules, a calculation of the daily food supply of estradiol by such edible tissues in comparison with the acceptable daily intake was performed. [source] Comparative proteomic analysis between normal skin and keloid scarBRITISH JOURNAL OF DERMATOLOGY, Issue 6 2010C.T. Ong Summary Background, Keloids are pathological scars and, despite numerous available treatment modalities, continue to plague physicians and patients. Objectives, Identification of molecular mediators that contribute to this fibrotic phenotype. Methods, Two-dimensional gel electrophoresis, MALDI-TOF, Mascot online database searching algorithm and Melanie 5 gel analysis software were employed for comparative proteomic analysis between normal skin (NS) and keloid scar (KS) tissue extracts. Results, Seventy-nine protein spots corresponding to 23 and 32 differentially expressed proteins were identified in NS and KS, respectively. Isoforms of heat shock proteins, gelsolin, carbonic anhydrase and notably keratin 10 were strongly expressed in NS along with manganese superoxide dismutase, immune components, antitrypsin, prostatic binding protein and crystalline. Various classes of proteins were found either to be present or to be upregulated in keloid tissue: (i) inflammatory/differentiated keratinocyte markers: S100 proteins, peroxiredoxin I; (ii) wound healing proteins: gelsolin-like capping protein; (iii) fibrogenetic proteins: mast cell ,-tryptase, macrophage migration inhibitory factor (MIF); (iv) antifibrotic proteins: asporin; (v) tumour suppressor proteins: stratifin, galectin-1, maspin; and (vi) antiangiogenic proteins: pigment epithelium-derived factor. Significant increases in expression of asporin, stratifin, galectin-1 and MIF were observed by Western blot analysis in KS. Conclusions, This work has identified differentially expressed proteins specific to KS tissue extracts which can potentially be used as specific targets for therapeutic intervention. [source] Applied psychometrics in clinical psychiatry: the pharmacopsychometric triangleACTA PSYCHIATRICA SCANDINAVICA, Issue 5 2009P. Bech Objective:, To consider applied psychometrics in psychiatry as a discipline focusing on pharmacopsychology rather than psychopharmacology as illustrated by the pharmacopsychometric triangle. Method:, The pharmacopsychological dimensions of clinically valid effects of drugs (antianxiety, antidepressive, antimanic, and antipsychotic), of clinically unwanted effects of these drugs, and the patients' own subjective perception of the balance between wanted and unwanted effects are analysed using rating scales assessed by modern psychometric tests (item response theory models) Results:, Symptom rating scales fulfilling the item response theory models have been shown to be psychometrically valid outcome scales as their total scores are sufficient statistics for demonstrating dose,response relationship within the various classes of antianxiety, antidepressive, antimanic or antipsychotic drugs. The total scores of side-effect rating scales are, however, not sufficient statistics, implying that each symptom has to be analysed individually. Self-rating scales with very few items appear to be sufficient statistics when measuring the patients' own perception of quality of life. Conclusion:, Applied psychometrics in psychiatry have been found to cover a pharmacopsychometric triangle illustrating the measurements of wanted and unwanted effects of pharmacotherapeutic drugs as well as health-related quality of life. [source] Comparing response of SDF systems to near-fault and far-fault earthquake motions in the context of spectral regionsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 12 2001Anil K. Chopra Abstract In spite of important differences in structural response to near-fault and far-fault ground motions, this paper aims at extending well-known concepts and results, based on elastic and inelastic response spectra for far-fault motions, to near-fault motions. Compared are certain aspects of the response of elastic and inelastic SDF systems to the two types of motions in the context of the acceleration-, velocity-, and displacement-sensitive regions of the response spectrum, leading to the following conclusions. (1) The velocity-sensitive region for near-fault motions is much narrower, and the acceleration-sensitive and displacement-sensitive regions are much wider, compared to far-fault motions; the narrower velocity-sensitive region is shifted to longer periods. (2) Although, for the same ductility factor, near-fault ground motions impose a larger strength demand than far-fault motions,both demands expressed as a fraction of their respective elastic demands,the strength reduction factors Ry for the two types of motions are similar over corresponding spectral regions. (3) Similarly, the ratio um/u0 of deformations of inelastic and elastic systems are similar for the two types of motions over corresponding spectral regions. (4) Design equati ns for Ry (and for um/u0) should explicitly recognize spectral regions so that the same equations apply to various classes of ground motions as long as the appropriate values of Ta, Tb and Tc are used. (5) The Veletsos,Newmark design equations with Ta=0.04 s, Tb=0.35 s, and Tc=0.79 s are equally valid for the fault-normal component of near-fault ground motions. Copyright © 2001 John Wiley & Sons, Ltd. [source] Validation of a modified Flory-Huggins concept for description of hydrophobic organic compound sorption on dissolved humic substancesENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2002Anett Georgi Abstract Sorption coefficients(KDOC) on dissolved organic matter (DOM) have been determined by means of solid-phase microextraction (SPME) for hydrophobic organic compounds (HOCs) of various classes, for example, polycyclic aromatic hydrocarbons (PAHs), noncondensed arenes, and alkanes. Relating the KDOC values obtained to the octanol-water partition coefficients of the solutes results in class-specific correlations. Obviously, PAHs have a higher affinity to DOM than other HOCs with equal KOW values. The different KDOC to KOW correlations can be combined into one general formula based on a modified Flory-Huggins concept. It permits the calculation of sorption coefficients from the solubility parameters (,) and KOW values of the solutes and the solubility parameter of the sorbent. The latter value, which is specific to the DOM under consideration, can be determined from a single measured sorption coefficient. By applying the proposed Flory-Huggins concept, which is based on the presumption of nonspecific interactions between HOCs and DOM, the different affinities of PAHs, noncondensed arenes, and alkanes to DOM can be accurately predicted. [source] The synthetic cannabinoid WIN55212-2 decreases the intraocular pressure in human glaucoma resistant to conventional therapiesEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2001Anna Porcella Abstract The search for new ocular hypotensive agents represents a frontier of current eye research because blindness due to optic neuropathy occurs insidiously in 10% of all patients affected by glaucoma. Cannabinoids have been proposed to lower intraocular pressure by either central or peripheral effects but a specific mechanism for this action has never been elucidated. We recently demonstrated the presence of the central cannabinoid receptor (CB1) mRNA and protein in the human ciliary body. In the present study we show that the synthetic CB1 receptor agonist, WIN 55212,2, applied topically at doses of 25 or 50 µg (n = 8), decreases the intraocular pressure of human glaucoma resistant to conventional therapies within the first 30 min (15 ± 0.5% and 23 ± 0.9%, respectively). A maximal reduction of 20 ± 0.7% and 31 ± 0.6%, respectively, is reached in the first 60 min. These data confirm that CB1 receptors have direct involvement in the regulation of human intraocular pressure, and suggest that, among various classes of promising antiglaucoma agents, synthetic CB1 receptor agonists should deserve further research and clinical development. [source] MULTILOCUS GENETICS AND THE COEVOLUTION OF QUANTITATIVE TRAITSEVOLUTION, Issue 7 2006Michael Kopp Abstract We develop and analyze an explicit multilocus genetic model of coevolution. We assume that interactions between two species (mutualists, competitors, or victim and exploiter) are mediated by a pair of additive quantitative traits that are also subject to direct stabilizing selection toward intermediate optima. Using a weak-selection approximation, we derive analytical results for a symmetric case with equal locus effects and no mutation, and we complement these results by numerical simulations of more general cases. We show that mutualistic and competitive interactions always result in coevolution toward a stable equilibrium with no more than one polymorphic locus per species. Victimexploiter interactions can lead to different dynamic regimes including evolution toward stable equilibria, cycles, and chaos. At equilibrium, the victim is often characterized by a very large genetic variance, whereas the exploiter is polymorphic in no more than one locus. Compared to related one-locus or quantitative genetic models, the multilocus model exhibits two major new properties. First, the equilibrium structure is considerably more complex. We derive detailed conditions for the existence and stability of various classes of equilibria and demonstrate the possibility of multiple simultaneously stable states. Second, the genetic variances change dynamically, which in turn significantly affects the dynamics of the mean trait values. In particular, the dynamics tend to be destabilized by an increase in the number of loci. [source] Heterologous expression of a Rauvolfia cDNA encoding strictosidine glucosidase, a biosynthetic key to over 2000 monoterpenoid indole alkaloidsFEBS JOURNAL, Issue 8 2002Irina Gerasimenko Strictosidine glucosidase (SG) is an enzyme that catalyses the second step in the biosynthesis of various classes of monoterpenoid indole alkaloids. Based on the comparison of cDNA sequences of SG from Catharanthus roseus and raucaffricine glucosidase (RG) from Rauvolfia serpentina, primers for RT-PCR were designed and the cDNA encoding SG was cloned from R. serpentina cell suspension cultures. The active enzyme was expressed in Escherichia coli and purified to homogeneity. Analysis of its deduced amino-acid sequence assigned the SG from R. serpentina to family 1 of glycosyl hydrolases. In contrast to the SG from C. roseus, the enzyme from R. serpentina is predicted to lack an uncleavable N-terminal signal sequence, which is believed to direct proteins to the endoplasmic reticulum. The temperature and pH optimum, enzyme kinetic parameters and substrate specificity of the heterologously expressed SG were studied and compared to those of the C. roseus enzyme, revealing some differences between the two glucosidases. In vitro deglucosylation of strictosidine by R. serpentina SG proceeds by the same mechanism as has been shown for the C. roseus enzyme preparation. The reaction gives rise to the end product cathenamine and involves 4,21-dehydrocorynantheine aldehyde as an intermediate. The enzymatic hydrolysis of dolichantoside (N,-methylstrictosidine) leads to several products. One of them was identified as a new compound, 3-isocorreantine A. From the data it can be concluded that the divergence of the biosynthetic pathways leading to different classes of indole alkaloids formed in R. serpentina and C. roseus cell suspension cultures occurs at a later stage than strictosidine deglucosylation. [source] An epidemic of plasmids?FEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2008Dissemination of extended-spectrum cephalosporinases among Salmonella, other Enterobacteriaceae Abstract CTX-M- and AmpC-type ,-lactamases comprise the two most rapidly growing populations among the extended-spectrum cephalosporinases. The evolution and dissemination of resistance genes encoding these enzymes occur mostly through the transmission of plasmids. The high prevalence of clinical isolates of Enterobacteriaceae producing the plasmid-mediated extended-spectrum cephalosporinases resembles an epidemic of plasmids, and has generated serious therapeutic problems. This review describes the emergence and worldwide spread of various classes of plasmid-mediated extended-spectrum cephalosporinases in Salmonella and other Enterobacteriaceae, the transfer mechanism of the plasmids, detection methods, and therapeutic choices. [source] Towards a better QALY modelHEALTH ECONOMICS, Issue 7 2006José-María Abellán-Perpiñán Abstract This paper presents a test of the predictive validity of various classes of QALY models (i.e. linear, power and exponential models). We first estimated TTO utilities for 43 EQ-5D chronic health states and next these states were embedded in nonchronic health profiles. The chronic TTO utilities were then used to predict the responses to TTO questions with nonchronic health profiles. We find that the power QALY model clearly outperforms linear and exponential QALY models. Optimal power coefficient is 0.65. Our results suggest that TTO-based QALY calculations may be biased. This bias can be corrected using a power QALY model. Copyright © 2006 John Wiley & Sons, Ltd. [source] Functional genomics studies on the innate immunity of disease vectorsINSECT SCIENCE, Issue 1 2008Luke A. Baton Abstract The increasing availability of genome sequences and the development of high-throughput techniques for gene expression profiling and functional characterization are transforming the study of innate immunity and other areas of insect biology. Already, functional genomic approaches have enabled a quantum advance in the characterization of mosquito immune responses to malaria parasite infection, and similar high-throughput functional genomic studies of other vector-pathogen interactions can be expected in the near future. The application of microarray-based and other expression analyses provide genome-wide transcriptional profiles that can be used to identify insect immune system components that are differentially regulated upon exposure to various classes of pathogens, including many important etiologic agents of human and animal diseases. The role of infection-responsive or other candidate immune genes identified through comparative genomic approaches can then be functionally characterized, either in vivo, for instance in adult mosquitoes, or in vitro using cell lines. In most insect vectors of human pathogens, germ-line transgenesis is still technically difficult and maintenance of multiple transgenic lines logistically demanding. Consequently, transient RNA interference (RNAi)-mediated gene-silencing has rapidly become the method of choice for functional characterization of candidate innate immune genes. The powerful combination of transcriptional profiling in conjunction with assays using RNAi to determine gene function, and identify regulatory pathways, together with downstream cell biological approaches to determine protein localization and interactions, will continue to provide novel insights into the role of insect innate immunity in a variety of vector-pathogen interactions. Here we review advances in functional genomics studies of innate immunity in the insect disease vectors, over the past decade, with a particular focus on the Anopheles mosquito and its responses to malaria infection. [source] Tracking of multiple target types with a single neural extended Kalman filterINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 5 2010Kathleen A. Kramer The neural extended Kalman filter is an adaptive state estimation routine that can be used in target-tracking systems to aid in the tracking through maneuvers without prior knowledge of the targets' dynamics. Within the neural extended Kalman filter, a neural network is trained using a Kalman filter training paradigm that is driven by the same residual as the state estimator. The difference between the a priori model used in the prediction steps of the estimator and the actual target dynamics is approximated. An important benefit of the technique is its versatility because little if any a priori knowledge of the target dynamics is needed. This allows the technique to be used in a generic tracking system that will encounter various classes of targets. In this paper, the neural extended Kalman filter is applied simultaneously to three separate classes of targets, each with different maneuver capabilities. The results show that the approach is well suited for use within a tracking system with multiple possible or unknown target characteristics. © 2010 Wiley Periodicals, Inc. [source] L2 -absolute and input-to-state stabilities of equations with nonlinear causal mappingsINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 2 2009M. I. Gil' Abstract Nonlinear scalar equations with causal mappings are considered. These equations include differential, difference, differential-delay, integro-differential and other traditional equations. Estimates for the L2 -norms of solutions are established. These estimates give us explicit conditions for the absolute and input-to-state stabilities of the considered equations. The Aizerman-type problem from the theory of absolute stability is also discussed. The suggested approach enables us to consider various classes of systems from the unified point of view. Copyright © 2008 John Wiley & Sons, Ltd. [source] Achieving a near-optimum erasure correction performance with low-complexity LDPC codesINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 5-6 2010Gianluigi Liva Abstract Low-density parity-check (LDPC) codes are shown to tightly approach the performance of idealized maximum distance separable (MDS) codes over memoryless erasure channels, under maximum likelihood (ML) decoding. This is possible down to low error rates and even for small and moderate block sizes. The decoding complexity of ML decoding is kept low thanks to a class of decoding algorithms, which exploit the sparseness of the parity-check matrix to reduce the complexity of Gaussian elimination. ML decoding of LDPC codes is reviewed at first. A performance comparison among various classes of LDPC codes is then carried out, including a comparison with fixed-rate Raptor codes for the same parameters. The results confirm that a judicious LDPC code design allows achieving a near-optimum performance over the erasure channel, with very low error floors. Furthermore, it is shown that LDPC and Raptor codes, under ML decoding, provide almost identical performance in terms of decoding failure probability vs. overhead. Copyright © 2010 John Wiley & Sons, Ltd. [source] The continuous cooling transformation (CCT) as a flexible tool to investigate polymer crystallization under processing conditionsADVANCES IN POLYMER TECHNOLOGY, Issue 2 2009V. Brucato Abstract An experimental route for investigating polymer crystallization over a wide range of cooling rates (from 0.01 to 1000°C/s) and pressures (from 0.1 to 40 MPa) is illustrated, using a method that recalls the approach adopted in metallurgy for studying structure development in metals. Two types of experimental setup were used, namely an apparatus for fast cooling of thin films (100,200 ,m thick) at various cooling rates under atmospheric pressure and a device (based on a on-purpose modified injection molding machine) for quenching massive samples (about 1,2 cm3) under hydrostatic pressure fields. In both cases, ex situ characterization experiments were carried out to probe the resulting structure, using techniques such as density measurements and wide-angle x-ray diffraction (WAXD) patterns. The cooling mechanism and temperature distribution across the sample thickness were analyzed. Results show that the final structure is determined only by the imposed thermal history and pressure. Experimental results for isotactic polypropylene (iPP), poly(ethylene terephthalate) (PET), polyamide 6 (PA6), and syndiotactic polystyrene (sPS) are reported, showing the reliability of this experimental approach to assess not only quantitative information but also a qualitative description of the crystallization behavior of different classes of semicrystalline polymers. The present study gives an opportunity to evaluate how the combined effect of the cooling rate and pressure influences the crystallization kinetics for various classes of polymer of commercial interest. An increase in the cooling rate translates into a decrease in crystallinity and density, which both experience a sudden drop around the specific "crystallizability" (or "critical cooling rate") of the material examined. The exception is sPS where competition among the various crystalline modifications determines a minimum in the plot of density vs. cooling rate. As for the effect of pressure, iPP exhibits a "negative dependence" of crystallization kinetics upon pressure, with a decrease of density and degree of crystallinity with increasing pressure, owing to kinetic constraints. PA6 and PET, on the other hand, due to thermodynamic factors resulting in an increase in Tm with pressure, exhibits a "positive dependence" of crystallization kinetics upon pressure. Finally, recent original results concerning sPS have shown that the minimum in the density vs. cooling rate curve shifts toward larger cooling rates upon increasing pressure. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 28:86,119, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20151 [source] Evaluating predictive performance of value-at-risk models in emerging markets: a reality checkJOURNAL OF FORECASTING, Issue 2 2006Yong Bao Abstract We investigate the predictive performance of various classes of value-at-risk (VaR) models in several dimensions,unfiltered versus filtered VaR models, parametric versus nonparametric distributions, conventional versus extreme value distributions, and quantile regression versus inverting the conditional distribution function. By using the reality check test of White (2000), we compare the predictive power of alternative VaR models in terms of the empirical coverage probability and the predictive quantile loss for the stock markets of five Asian economies that suffered from the 1997,1998 financial crisis. The results based on these two criteria are largely compatible and indicate some empirical regularities of risk forecasts. The Riskmetrics model behaves reasonably well in tranquil periods, while some extreme value theory (EVT)-based models do better in the crisis period. Filtering often appears to be useful for some models, particularly for the EVT models, though it could be harmful for some other models. The CaViaR quantile regression models of Engle and Manganelli (2004) have shown some success in predicting the VaR risk measure for various periods, generally more stable than those that invert a distribution function. Overall, the forecasting performance of the VaR models considered varies over the three periods before, during and after the crisis. Copyright © 2006 John Wiley & Sons, Ltd. [source] Mass defect filter technique and its applications to drug metabolite identification by high-resolution mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 7 2009Haiying Zhang Abstract Identification of drug metabolites by liquid chromatography/mass spectrometry (LC/MS) involves metabolite detection in biological matrixes and structural characterization based on product ion spectra. Traditionally, metabolite detection is accomplished primarily on the basis of predicted molecular masses or fragmentation patterns of metabolites using triple-quadrupole and ion trap mass spectrometers. Recently, a novel mass defect filter (MDF) technique has been developed, which enables high-resolution mass spectrometers to be utilized for detecting both predicted and unexpected drug metabolites based on narrow, well-defined mass defect ranges for these metabolites. This is a new approach that is completely different from, but complementary to, traditional molecular mass- or MS/MS fragmentation-based LC/MS approaches. This article reviews the mass defect patterns of various classes of drug metabolites and the basic principles of the MDF approach. Examples are given on the applications of the MDF technique to the detection of stable and chemically reactive metabolites in vitro and in vivo. Advantages, limitations, and future applications are also discussed on MDF and its combinations with other data mining techniques for the detection and identification of drug metabolites. Copyright © 2009 John Wiley & Sons, Ltd. [source] Human brain aminopeptidase A: biochemical properties and distribution in brain nucleiJOURNAL OF NEUROCHEMISTRY, Issue 1 2008Nadia De Mota Abstract Aminopeptidase A (APA) generated brain angiotensin III, one of the main effector peptides of the brain renin angiotensin system, exerting a tonic stimulatory effect on the control of blood pressure in hypertensive rats. The distribution of APA in human brain has not been yet studied. We first biochemically characterized human brain APA (apparent molecular mass of 165 and 130 kDa) and we showed that the human enzyme exhibited similar enzymatic characteristics to recombinant mouse APA. Both enzymes had similar sensitivity to Ca2+. Kinetic studies showed that the Km (190 ,mol/L) of the human enzyme for the synthetic substrate- l -glutamyl-,-naphthylamide was close from that of the mouse enzyme (256 ,mol/L). Moreover, various classes of inhibitors including the specific and selective APA inhibitor, (S)-3-amino-4-mercapto-butyl sulfonic acid, had similar inhibitory potencies toward both enzymes. Using (S)-3-amino-4-mercapto-butyl sulfonic acid, we then specifically measured the activity of APA in 40 microdissected areas of the adult human brain. Significant heterogeneity was found in the activity of APA in the various analyzed regions. The highest activity was measured in the choroids plexus and the pineal gland. High activity was also detected in the dorsomedial medulla oblongata, in the septum, the prefrontal cortex, the olfactory bulb, the nucleus accumbens, and the hypothalamus, especially in the paraventricular and supraoptic nuclei. Immunostaining of human brain sections at the level of the medulla oblongata strengthened these data, showing for the first time a high density of immunoreactive neuronal cell bodies and fibers in the motor hypoglossal nucleus, the dorsal motor nucleus of the vagus, the nucleus of the solitary tract, the Roller nucleus, the ambiguus nucleus, the inferior olivary complex, and in the external cuneate nucleus. APA immunoreactivity was also visualized in vessels and capillaries in the dorsal motor nucleus of the vagus and the inferior olivary complex. The presence of APA in several human brain nuclei sensitive to angiotensins and involved in blood pressure regulation suggests that APA in humans is an integral component of the brain renin angiotensin system and strengthens the idea that APA inhibitors could be clinically tested as an additional therapy for the treatment of certain forms of hypertension. [source] Design of anticancer prodrugs for reductive activationMEDICINAL RESEARCH REVIEWS, Issue 1 2009Yu Chen Abstract Anticancer prodrugs designed to target specifically tumor cells should increase therapeutic effectiveness and decrease systemic side effects in the treatment of cancer. Over the last 20 years, significant advances have been made in the development of anticancer prodrugs through the incorporation of triggers for reductive activation. Reductively activated prodrugs have been designed to target hypoxic tumor tissues, which are known to overexpress several endogenous reductive enzymes. In addition, exogenous reductive enzymes can be delivered to tumor cells through fusion with tumor-specific antibodies or overexpressed in tumor cells through gene delivery approaches. Many anticancer prodrugs have been designed to use both the endogenous and exogenous reductive enzymes for target-specific activation and these prodrugs often contain functional groups such as quinones, nitroaromatics, N-oxides, and metal complexes. Although no new agents have been approved for clinical use, several reductively activated prodrugs are in various stages of clinical trial. This review mainly focuses on the medicinal chemistry aspects of various classes of reductively activated prodrugs including design principles, structure-activity relationships, and mechanisms of activation and release of active drug molecules. © 2008 Wiley Periodicals, Inc. Med Res Rev, 29, No. 1, 29,64, 2009 [source] The nature of the Sloan Digital Sky Survey galaxies in various classes based on morphology, colour and spectral features , III.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2010Environments ABSTRACT We present a study on the environments of the Sloan Digital Sky Survey (SDSS) galaxies divided into fine classes based on their morphology, colour and spectral features. The SDSS galaxies are classified into early-type and late-type; red and blue; passive, H ii, Seyfert and low-ionization nuclear emission-line region (LINER), which returns a total of 16 fine classes of galaxies. We estimate the local number density, target-excluded local luminosity density, local colour, close pair fraction and the luminosity and colour of the brightest neighbour, which are compared between the fine classes comprehensively. The morphology,colour class of galaxies strongly depends on the local density, with the approximate order of high-density preference: red early-type galaxies (REGs); red late-type galaxies (RLGs); blue early-type galaxies (BEGs) and blue late-type galaxies (BLGs). We find that high-density environments (like cluster environments) seem to suppress active galactic nucleus activity. The pair fraction of H ii REGs does not show a statistically significant difference from that of passive REGs, while the pair fraction of H ii BLGs is smaller than that of non-H ii BLGs. H ii BLGs show obvious double (red + blue) peaks in the distribution of the brightest neighbour colour, while red galaxies show a single red peak. The brightest neighbours of Seyfert BLGs tend to be blue, while those of LINER BLGs tend to be red, which implies that the difference between Seyfert and LINER may be related to the pair interaction. Other various environments of the fine classes are investigated, and their implications for galaxy evolution are discussed. [source] Matching preclusion for some interconnection networksNETWORKS: AN INTERNATIONAL JOURNAL, Issue 2 2007Eddie Cheng Abstract The matching preclusion number of a graph is the minimum number of edges whose deletion results in a graph that has neither perfect matchings nor almost-perfect matchings. In this paper, we find this number for various classes of interconnection networks and classify all the optimal solutions. © 2007 Wiley Periodicals, Inc. NETWORKS, Vol. 50(2), 173,180 2007 [source] Validated simulation of kinematics and dynamics of multibody systems using interval and Taylor model based methodsPROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2007Ekaterina Auer In this paper, we present an integrated environment for validated modeling and simulation of kinematics and dynamics of various classes of mechanical systems SMARTMOBILE (Simulation and Modeling of dynAmics in MOBILE: Reliable and Template,based) built on top of the non-validated tool MOBILE. We outline the main features of SMARTMOBILE and its applicability area. The functionality of the new tool and the importance of the application of validated techniques are demonstrated. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Method for estimating decomposition characteristics of energetic chemicalsPROCESS SAFETY PROGRESS, Issue 4 2003Sima Chervin Experimental data on the decomposition characteristics of approximately400 chemicals, representing various classes of energetic materials, were summarized by chemical class and statistically analyzed. Average decomposition characteristics, such as energy of decomposition and decomposition onset temperature, were determined for chemical classes containing the following energetic groups: nitro, nitroso, N-oxide, oxime, hydroxylamine, tetrazole, azide, triazene, triazole, diazo, azo, hydrazine, and perchlorate. Additional statistical information is presented for each chemical class, such as number of chemicals analyzed, ranges, and standard deviations for the decomposition parameters analyzed. For chemical classes containing an energetic group attached to an aromatic ring, the presence and position of another substituting group in the ring can significantly influence the decomposition onset temperature. The study summarizes the list of activating and deactivating functional groups, and the positions in the ring where the strongest activation or deactivation occurs. The authors also recommend a method for estimating decomposition parameters of new chemicals. [source] The Effects of Oral Administration of D-Modafinil on Male Rat Ejaculatory BehaviorTHE JOURNAL OF SEXUAL MEDICINE, Issue 1pt1 2010Lesley Marson PhD ABSTRACT Introduction., Premature ejaculation (PE) is one of the most common forms of male sexual dysfunction. Examination of various classes of drugs on ejaculation latency would provide further opportunities for drug development in this field. Aim., This study was conducted to examine the effects of the d-isomer of modafinil (d-modafinil) on ejaculatory behavior in a rat model. Methods., Male sexual behavior in the rat was examined after acute oral administration of d-modafinil (10 mg/kg, 30 mg/kg, and 100 mg/kg) in copulation studies with receptive females. Main Outcome Measures., The latency to ejaculation, post-ejaculatory interval, and the frequency of mounting behavior were measured. Results d-modafinil (30 mg/kg and 100 mg/kg) produced a significant delay in ejaculation. The delay in ejaculation was accompanied by an increase in the number of intromissions without any change in the mount or intromission latency. The possible mechanisms of action of d-modafinil to produce this delay in ejaculation are discussed. Conclusions., These results demonstrate that acute oral administration of d-modafinil can lengthen the latency to ejaculation in rats without suppressing sexual behavior. The greatest delay in ejaculation was observed in animals with shorter baseline ejaculatory latencies. Investigation into new classes of drugs that modulate ejaculation may provide new therapeutic options for treating PE. Marson L, Yu G, and Farber NM. The effects of oral administration of d-modafinil on male rat ejaculatory behavior. J Sex Med 2010;7:70,78. [source] A simple test of exponentiality against NWBUE family of life distributionsAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 1 2005M. Z. Anis Abstract In this paper we propose a simple procedure to test the null hypothesis of exponentiality against the alternative that it belongs to the new worse then better than used in expectation (NWBUE) family. The test is shown to be consistent and the asymptotic distribution of the test statistic has been obtained. The performance of the test against various classes of alternatives has been studied by means of simulation. Copyright © 2005 John Wiley & Sons, Ltd. [source] Pulsations and planets: The asteroseismology-extrasolar-planet connectionASTRONOMISCHE NACHRICHTEN, Issue 5 2010S. Schuh Abstract The disciplines of asteroseismology and extrasolar planet science overlap methodically in the branch of high-precision photometric time series observations. Light curves are, amongst others, useful to measure intrinsic stellar variability due to oscillations, as well as to discover and characterize those extrasolar planets that transit in front of their host stars, periodically causing shallow dips in the observed brightness. Both fields ultimately derive fundamental parameters of stellar and planetary objects, allowing to study for example the physics of various classes of pulsating stars, or the variety of planetary systems, in the overall context of stellar and planetary system formation and evolution. Both methods typically also require extensive spectroscopic follow-up to fully explore the dynamic characteristics of the processes under investigation. In particularly interesting cases, a combination of observed pulsations and signatures of a planet allows to characterize a system's components to a very high degree of completeness by combining complementary information. The planning of the relevant space missions has consequently converged with respect to science cases, where at the outset there was primarily a coincidence in instrumentation and techniques. Whether space- or ground-based, a specific type of stellar pulsations can themselves be used in an innovative way to search for extrasolar planets. Results from this additional method at the interface of stellar pulsation studies and exoplanet hunts in a beyond-mainstream area are presented (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Computational framework for predictive biodegradationBIOTECHNOLOGY & BIOENGINEERING, Issue 6 2009Stacey D. Finley Abstract As increasing amounts of anthropogenic chemicals are released into the environment, it is vital to human health and the preservation of ecosystems to evaluate the fate of these chemicals in the environment. It is useful to predict whether a particular compound is biodegradable and if alternate routes can be engineered for compounds already known to be biodegradable. In this work, we describe a computational framework (called BNICE) that can be used for the prediction of novel biodegradation pathways of xenobiotics. The framework was applied to 4-chlorobiphenyl, phenanthrene, ,-hexachlorocyclohexane, and 1,2,4-trichlorobenzene, compounds representing various classes of xenobiotics with known biodegradation routes. BNICE reproduced the proposed biodegradation routes found experimentally, and in addition, it expanded the biodegradation reaction networks through the generation of novel compounds and reactions. The novel reactions involved in the biodegradation of 1,2,4-trichlorobenzene were studied in depth, where pathway and thermodynamic analyses were performed. This work demonstrates that BNICE can be applied to generate novel pathways to degrade xenobiotic compounds that are thermodynamically feasible alternatives to known biodegradation routes and attractive targets for metabolic engineering. Biotechnol. Bioeng. 2009; 104: 1086,1097. © 2009 Wiley Periodicals, Inc. [source] Cyclopentenone Eicosanoids as Mediators of Neurodegeneration: A Pathogenic Mechanism of Oxidative Stress-Mediated and Cyclooxygenase-Mediated NeurotoxicityBRAIN PATHOLOGY, Issue 2 2005Erik S. Musiek The activation of cyclooxygenase enzymes in the brain has been implicated in the pathogenesis of numerous neurodegenerative conditions. Similarly, oxidative stress is believed to be a major contributor to many forms of neurodegeneration. These 2 distinct processes are united by a common characteristic: the generation of electrophilic cyclopentenone eicosanoids. These cyclopentenone compounds are defined structurally by the presence of an unsaturated carbonyl moiety in their prostane ring, and readily form Michael adducts with cellular thiols, including those found in glutathione and proteins. The cyclopentenone prostaglandins (PGs) PGA2, PGJ2, and 15-deoxy-,12,14 PGJ2, enzymatic products of cyclooxygenase-mediated arachidonic acid metabolism, exert a complex array of potent neurodegenerative, neuroprotective, and anti-inflammatory effects. Cyclopentenone isoprostanes (A2/J2 -IsoPs), products of non-enzymatic, free radical-mediated arachidonate oxidation, are also highly bioactive, and can exert direct neurodegenerative effects. In addition, cyclopentenone products of docosahexaenoic acid oxidation (cyclopentenone neuroprostanes) are also formed abundantly in the brain. For the first time, the formation and biological actions of these various classes of reactive cyclopentenone eicosanoids are reviewed, with emphasis on their potential roles in neurodegeneration. The accumulating evidence suggests that the formation of cyclopentenone eicosanoids in the brain may represent a novel pathogenic mechanism, which contributes to many neurodegenerative conditions. [source] Wnt signaling inside the nucleusCANCER SCIENCE, Issue 4 2008Miki Shitashige Accumulation of the ,-catenin protein and transactivation of a certain set of T-cell factor (TCF)-4 target genes by accumulated ,-catenin have been considered crucial in colorectal carcinogenesis. In the present review, we summarize nuclear proteins that interact with, and regulate, the ,-catenin and TCF and lymphoid enhancer factor (LEF) transcriptional complexes. Our recent series of proteomic studies has also revealed that various classes of nuclear proteins participate in the ,-catenin,TCF-4 complex and modulate its transcriptional activity. Furthermore, the protein composition of the TCF-4-containing nuclear complex is not fixed, but is regulated dynamically by endogenous programs associated with intestinal epithelial cell differentiation and exogenous stimuli. Restoration of the loss-of-function mutation of the adenomatous polyposis coli (APC) gene in colorectal cancer cells does not seem to be a realistic approach with currently available medical technologies, and only signaling molecules downstream of the APC gene product can be considered as targets of pharmacological intervention. Nuclear proteins associated with the ,-catenin,TCF-4 complex may include feasible targets for molecular therapy against colorectal cancer. Recently, an inhibitor of the interaction between CREB-binding protein and ,-catenin was shown to efficiently shut down the transcriptional activity of TCF-4 and induce apoptosis of colorectal cancer cells. We also summarize current strategies in the development of drugs against Wnt signaling. (Cancer Sci 2008; 99: 631,637) [source] | ||||||||||||||||||||||||||||