bluuebunny/crossref_metadata_2025 huggingface dataset:
Mutasynthesis‐Derived Myxalamids and Origin of the Isobutyryl‐CoA Starter Unit of Myxalamid B
Authors: Bode Helge B. , Meiser Peter , Klefisch Thorsten , Cortina Niña Socorro d. J. , Krug Daniel , Göhring Anke , Schwär Gertrud , Mahmud Taifo , Elnakady Yasser A. , Müller Rolf
Published: October 2007

Myxalamids are potent inhibitors of the eukaryotic electron transport chain produced by different myxobacteria. Here, we describe the identification of the myxalamid biosynthesis gene cluster from Myxococcus xanthus. Additionally, new myxalamids (5–13) have been obtained by mutasynthesis from bkd mutants of M. xanthus and Stigmatella aurantiaca. Moreover, as these bkd mutants are still able to produce myxalamid B (2), the origin of the isobutyryl‐CoA (IB‐CoA) starter unit required for its biosynthesis has been determined. In a M. xanthus bkd mutant, IB‐CoA originates from valine, but in S. aurantiaca this starter unit is derived from α‐oxidation of iso‐odd fatty acids, thereby connecting primary and secondary metabolism.
Dynamics underlying synaptic gain between pairs of cortical pyramidal neurons
Authors: Pratt Kara G. , Taft Christine E. , Burbea Michelle , Turrigiano Gina G.
Published: October 2007

Changes in connectivity between pairs of neurons can serve as a substrate for information storage and for experience‐dependent changes in neuronal circuitry. Early in development, synaptic contacts form and break, but how these dynamics influence the connectivity between pairs of neurons is not known. Here we used time‐lapse imaging to examine the synaptic interactions between pairs of cultured cortical pyramidal neurons, and found that the axon–dendrite contacts between each neuronal pair were composed of both a relatively stable and a more labile population. Under basal conditions, loss and gain of contacts within this labile population was well balanced and there was little net change in connectivity. Selectively increasing the levels of activated CaMKII in the postsynaptic neuron increased connectivity between pairs of neurons by increasing the rate of gain of new contacts without affecting the probability of contact loss, or the proportion of stable and labile contacts, and this increase required Calcium/calmodulin binding to CaMKII. Our data suggest that activating CaMKII can increase synaptic connectivity through a CaM‐dependent increase in contact formation, followed by stabilization of a constant fraction of new contacts. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2008
Sexual dimorphism and androgen regulation of satellite cell population in differentiating rat levator ani muscle
Authors: Niel Lee , Willemsen Kristin R. , Volante Sonia N. , Monks Douglas Ashley
Published: October 2007

The bulbocavernosus (BC) and levator ani (LA) muscles of rats show remarkable androgen‐dependent sexual dimorphism. These muscles are additionally of interest because they are thought to indirectly mediate sexual differentiation of innervating spinal motoneurons. This sexual differentiation of the BC/LA is thought to be due to an increase in muscle units in the male rat during the first week after birth. We examined the cellular basis of this differentiation by studying satellite cells in the LA of postnatal day 2.5 rats, when sexual dimorphism is already prominent. Two experiments were performed in which LA satellite cells were measured: (1) wild‐type (WT) males were compared with females and to Tfm androgen receptor mutant males, which are androgen insensitive despite producing masculine amounts of testosterone, and (2) females treated prenatally and/or postnatally with testosterone proprionate were compared with females receiving vehicle injections. Our results indicate that WT males have a larger LA and a greater number of satellite cells in the LA muscle than females or Tfm males. However, satellite cell density was similar for all three groups. Prenatal testosterone treatment masculinized LA size and resulted in a corresponding increase in satellite cell populations, while postnatal TP treatment resulted in a tendency for increased satellite cell density without a significant increase in LA size. Taken together, these studies indicate that satellite cells in the neonatal LA muscle are sexually dimorphic, and that this dimorphism likely results from perinatal actions of androgens on androgen receptors. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2008
Enhancer detection in the ascidianCiona intestinaliswith transposase‐expressing lines ofMinos
Authors: Sasakura Yasunori , Konno Aru , Mizuno Katsutoshi , Satoh Nori , Inaba Kazuo
Published: October 2007

Germline transgenesis with a Tc1/marinersuperfamilyMinostransposon was achieved in the ascidianCiona intestinalis. Transgenic lines that express transposases in germ cells are very useful for remobilizing transposon copies. In the present study, we created transposase‐expressing lines ofMinosinCiona. ACionagene encoding protamine (Ci‐prm) is expressed in the testes and sperm. Transgenic lines expressingMinostransposase in the testes and sperm were created with acis‐element ofCi‐prm, and used for enhancer detection. Double‐transgenic animals between transposase lines and a transgenic line with an enhancer detection vector passed on several independent enhancer detection events to subsequent progeny. This technique allowed us to isolate transgenic lines that express GFP in restricted tissues. This system provides an easy and efficient method for large‐scale enhancer detection inCiona intestinalis. Developmental Dynamics 237:39–50, 2008. © 2007 Wiley‐Liss, Inc.
Abortive placode formation in the feather tract of the scaleless chicken embryo
Authors: Houghton Leslie , Lindon Catherine M. , Freeman Allison , Morgan Bruce A.
Published: October 2007

The featherless phenotype of the scaleless mutant provides a model for delineating the process of feather follicle formation. Initial studies established that the mutation affects the epidermis and suggested that epidermis is unable to respond to signals from underlying dermis, or propagate a reciprocal signal. The work presented here demonstrates that scaleless epidermis does indeed respond to the initial inductive signals from dermis, as indicated by the localization of nuclear β‐catenin and transient focal expression of genes expressed in the placode of wild‐type feather rudiments. In the sporadic “escaper” feathers that form in scaleless, expression of many genes associated with the progression of feather development is comparable to that in wild‐type embryos. An exception is the ectodysplasin receptor gene Edar, which is expressed at lower levels in mutant feather buds. These observations suggest that the scaleless mutation impairs the locally augmented expression of Edar required to stabilize the placodal fate and sustain feather development. Developmental Dynamics 236:3020–3030, 2007. © 2007 Wiley‐Liss, Inc.
Commentary on ‘Therapeutic interventions for Burkitt's lymphoma in children’
Authors: Macharia William M.
Published: October 2007

This is a commentary on a Cochrane review, published in this issue of EBCH, first published as: Okebe JU, Lasserson TJ, Meremikwu MM, Richards S. Therapeutic interventions for Burkitt's lymphoma in children. Cochrane Database of Systematic Reviews 2006, Issue 4. Art. No.: CD005198. DOI: 10.1002/14651858.CD005198.pub2.

Further information for this Cochrane review is available in this issue of EBCH in the accompanying EBCH Summary and Characteristics and Key Findings Tables articles. Copyright © 2007 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. The Cochrane Collaboration
The Cochrane Library and trachoma: an overview of reviews
Authors: Sumamo Elizabeth , Emerson Paul , Harvey Krystal , Burton Matthew
Published: October 2007

Background:

Trachoma is the leading infectious cause of blindness worldwide. Active trachoma is caused by the bacterium Chlamydia trachomatis. Recurrent infection over many years may lead to scarring of the conjunctiva, entropion, trachomatous trichiasis and corneal opacity.

Objective:

To summarize Cochrane reviews that assess the effect of SAFE strategy (surgery, antibiotics, face washing and environmental change) for trachoma in developing countries.

Methods:

The Cochrane Database of Systematic Reviews was searched for any intervention to prevent or treat trachoma. Data was extracted in duplicate and analyzed.

Main Results:

There were four systematic reviews addressing trachoma, all of which met the inclusion criteria. There was some evidence that the prevalence of active trachoma was reduced by the use of antibiotics. At three months, six of nine trials found a significant reduction in relative risk of active trachoma in the intervention groups. At 12 months, only three of six studies found a significant reduction. Oral azithromycin performed better than topical tetracycline at clearing infection at three months, but not at resolving clinical signs. There is evidence that face washing in combination with topical tetracycline antibiotics can reduce the prevalence of severe trachoma compared to face washing alone. Insecticide spray as a fly control measure significantly reduced trachoma and health education may be effective in reducing active trachoma.

Full thickness incision of the tarsal plate was found to be the most successful type of surgery for trichiasis. Tarsal rotation surgery was also found to be more effective than non‐surgical techniques for minor trichiasis. This surgery was equally effective when performed by appropriate trained ophthalmic nurses and ophthalmologists and also when conducted in a health centre or village setting.

Authors' Conclusions:

There are no clinical trials of the full SAFE strategy for trachoma control on blindness prevention, or on reducing active trachoma, or ocular Chlamydia trachomatis infection. However, there is some evidence that separately supports each of the components of SAFE: surgery, antibiotics, facial cleanliness, and environmental improvements. Programmatically, continued delivery of the full SAFE strategy is warranted and can be expected to have a positive impact on the control of blinding trachoma. Copyright © 2007 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. The Cochrane Collaboration
Sharpness comparison method for various medical imaging systems
Authors: Ukishima Masayuki , Nakaguchi Toshiya , Kato Katsushi , Fukuchi Yoshikazu , Tsumura Norimichi , Matsumoto Kazumasa , Yanagawa Noriyuki , Ogura Takashi , Kikawa Takashi , Miyake Yoichi
Published: October 2007

In recent years, many kinds of displays and recording systems for X‐ray medical images have appeared. In this paper, sharpness of X‐ray images displayed onto high‐accuracy monochrome CRT and LCD monitors was analyzed and compared. Images recorded on the exclusive film and coated paper by inkjet printer and the wet‐type and dry‐type photo printers using a silver halide material were also analyzed and compared. The modified Gan's method was introduced to calculate the modulation transfer function (MTF) from the edge spread function (ESF). The results showed that the MTFs of the LCD, the inkjet image on the transparency, and the wet‐type silver halide film image have fairly similar and good response in comparison with the inkjet image on the glossy paper and the dry‐type silver halide film. It was also shown that the CRT has the worst response over the spatial frequency range. It was well correlated between the MTF and observer rating value. We thus consider the proposed method to be effective. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 65–73, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20404
Development and evaluation of message passing library for Maestro2 cluster network
Authors: Aoki Keiichi , Yamagiwa Shinichi , Wada Koichi , Ono Masaaki
Published: October 2007

Cluster computers applying personal computers (PC) to their processing nodes have been widely used as parallel computational platforms due to the improvements of cost/performance ratio. In order to achieve higher performance of a cluster computer, it is important to be considered not only an approach to improve the network performance but also the one to overlap computation with communication. To confirm the validity of the latter approach, we are developing the Maestro2 cluster network which is composed of general‐purpose processors and dedicated communication hardware tightly coupled with those processors. This paper describes a design and implementation of a communication library of a message passing system, called MMP, over the Maestro2 cluster network. On MMP, the processor on the Maestro cluster network controls the hardware and processes almost all communication steps such as for sending/receiving messages and a synchronization among processing units. According to an experimental evaluation, this paper shows that MMP achieves higher throughput than the conventional communication method that is processed by a host processor. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 109–121, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20411
Blind identification of MIMO discrete‐time systems based on independent component analysis
Authors: Nitta Masuhiro , Sugimoto Kenji
Published: October 2007

This paper proposes a blind identification algorithm of a multivariate autoregressive moving average model based on independence of source signals. In such a model, it is difficult to perform blind identification due to nonlinear regression problems. This difficulty is overcome by introducing a feedback structure into the independent component analysis. By using a polynomial matrix fraction, coefficients matrices are exactly identified whereas a conventional method gives mere approximate results. The effectiveness of the proposed method has been confirmed through numerical simulations. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 17–25, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20418
Impaired T cell activation and increased Th2 lineage commitment in Annexin‐1‐deficient T cells
Authors: D'Acquisto Fulvio , Paschalidis Nikolaos , Sampaio Andre L. F. , Merghani Ahmed , Flower Roderick J. , Perretti Mauro
Published: October 2007

Annexin‐1 is a well‐known endogenous anti‐inflammatory protein that modulates the activation of cells of the innate immune system such as neutrophils and macrophages. We have recently reported a positive role for the exogenous protein on T cell differentiation, however, whether such a role holds true for the endogenous protein has yet to be determined. This aspect has been investigated here finding that Annexin‐1‐deficient T cells display an impaired activation and proliferation in response to anti‐CD3 plus anti‐CD28 stimulation. Furthermore, differentiation of T cells from Annexin‐1‐deficient mice in Th0/Th1/Th2 or Th17 skewing conditions demonstrated an increased Th2 phenotype compared to cells from control littermates. Similar results were obtained when we analyzed the Th1/Th2 profile of lymph node cells obtained from mice immunized with keyhole limpet hemocyanin or the inflammatory infiltrate in mouse model of allergic inflammation. These results demonstrate a novel modulatory role of endogenous Annexin‐1 in TCR signaling and T cell differentiation and suggest this protein might play a dual and complementary role in the innate and adaptive immune response.
Identification of a novel negative role of flagellin in regulating IL‐10 production
Authors: Vicente‐Suarez Ildefonso , Takahashi Yoshinori , Cheng Fengdong , Horna Pedro , Wang Hong W. , Wang Hong‐Gang , Sotomayor Eduardo M.
Published: October 2007

Toll‐like receptors (TLR) expressed by cells of the immune system play a central role in the generation of immune responses against pathogens. Following TLR ligation, both pro‐inflammatory and anti‐inflammatory mediators are produced in order to elicit an immune response that controls the microbial infection while limiting tissue damage. Among these mediators, the pro‐inflammatory cytokine IL‐12 and the anti‐inflammatory cytokine IL‐10 are known to play major roles. Here, we show that in vitro or in vivo stimulation with flagellin, the TLR5 ligand, does not result in IL‐10 production. Furthermore, flagellin inhibits IL‐10 production by other specific TLR ligands at the protein and mRNA levels while increasing IL‐12p70 production. Several studies have linked the activation of extracellular signal‐regulated kinases with IL‐10 induction by TLR. We have observed that LPS‐induced extracellular signal‐regulated kinase activation was significantly decreased in flagellin‐treated macrophages, suggesting that this pathway might play a role in the inhibition of IL‐10 production observed in flagellin‐treated macrophages. Flagellin‐mediated IL‐10 inhibition was not observed in cells that do not express TLR5, supporting that this effect is indeed TLR5‐dependent. This study provides a new insight into the role of flagellin recognition by TLR5 in shaping the immune response elicited by flagellated microorganisms.
T cell independent mechanism for copolymer‐1‐induced neuroprotection
Authors: Liu Jianuo , Johnson Thomas V. , Lin Jamie , Ramirez Servio H. , Bronich Tatiana K. , Caplan Steve , Persidsky Yuri , Gendelman Howard E. , Kipnis Jonathan
Published: October 2007

Despite active investigation of copolymer‐1 (Cop‐1) for nearly 40 years the mechanisms underlying its neuroprotective properties remain contentious. Nonetheless, current dogma for Cop‐1 neuroprotective activities in autoimmune and neurodegenerative diseases include bystander suppression of autoimmune T cells and attenuation of microglial responses. In this report, we demonstrate that Cop‐1 interacts directly with primary human neurons and decreases neuronal cell death induced by staurosporine or oxidative stress. This neuroprotection is mediated through protein kinase Cα and brain‐derived neurotrophic factor. Dendritic cells (DC) uptake Cop‐1, deliver it to the injury site, and release it in an active form. Interactions between Cop‐1 and DC enhance DC blood brain barrier migration. In a rat model with optic nerve crush injury, Cop‐1‐primed DC induce T cell independent neuroprotection. These findings may facilitate the development of neuroprotective approaches using DC‐mediated Cop‐1 delivery to diseased nervous tissue.
Immunisation with BCG and recombinant MVA85A induces long‐lasting, polyfunctional Mycobacterium tuberculosis‐specific CD4+ memory T lymphocyte populations
Authors: Beveridge Natalie E. R. , Price David A. , Casazza Joseph P. , Pathan Ansar A. , Sander Clare R. , Asher Tedi E. , Ambrozak David R. , Precopio Melissa L. , Scheinberg Phillip , Alder Nicola C. , Roederer Mario , Koup Richard A. , Douek Daniel C. , Hill Adrian V. S. , McShane Helen
Published: October 2007

In the search for effective vaccines against intracellular pathogens such as HIV, tuberculosis and malaria, recombinant viral vectors are increasingly being used to boost previously primed T cell responses. Published data have shown prime‐boost vaccination with BCG‐MVA85A (modified vaccinia virus Ankara expressing antigen 85A) to be highly immunogenic in humans as measured by ex vivo IFN‐γ ELISPOT. Here, we used polychromatic flow cytometry to investigate the phenotypic and functional profile of these vaccine‐induced Mycobacterium tuberculosis (M.tb) antigen 85A‐specific responses in greater detail. Promisingly, antigen 85A‐specific CD4+ T cells were found to be highly polyfunctional, producing IFN‐γ, TNF‐α, IL‐2 and MIP‐1β. Surface staining showed the responding CD4+ T cells to be relatively immature (CD45RO+ CD27intCD57–); this observation was supported by the robust proliferative responses observed following antigenic stimulation. Furthermore, these phenotypic and functional properties were independent of clonotypic composition and epitope specificity, which was maintained through the different phases of the vaccine‐induced immune response. Overall, these data strongly support the use of MVA85A in humans as a boosting agent to expand polyfunctional M.tb‐specific CD4+ T cells capable of significant secondary responses.
The role of lymphoid tissue inducer cells in splenic white pulp development
Authors: Withers David R. , Kim Mi‐Yeon , Bekiaris Vasileios , Rossi Simona W. , Jenkinson William E. , Gaspal Fabrina , McConnell Fiona , Caamano Jorge H. , Anderson Graham , Lane Peter J. L.
Published: October 2007

CD4+CD3– lymphoid tissue inducer (LTi) cells are crucial for the development and organisation of lymph nodes and gut associated lymphoid tissues. In this report, we characterise their appearance in the developing spleen and highlight their importance in relation to the development of splenic T cell zones. LTi cells were detected in embryonic spleen from embryonic day 13, although their progenitors were present at embryonic day 12. These cells clustered initially around splenic blood vessels in a lymphotoxin (LT)‐independent manner, but up‐regulation of VCAM‐1 expression on stromal cells associated with the blood vessels was LT dependent. After birth, T cell colonisation of these clusters to form nascent white pulp areas was also LT dependent. Transfer experiments reconstituting RAG–/– mice with either WT or LTα–/– splenocytes demonstrated that lymphocyte expression of LT was not essential for the organisation of a discrete CD3+ T cell zone with localised podoplanin and CCL21 expression. Our studies indicate that a combination of LT signals from LTi cells and LT‐independent signals from lymphocytes is sufficient for expression of podoplanin and CCL21 on splenic T cell zone stroma and subsequent T cell organisation.
IL‐10 modulates cytokine gene transcription by protein synthesis‐independent and dependent mechanisms in lipopolysaccharide‐treated neutrophils
Authors: Rossato Marzia , Cencig Sabrina , Gasperini Sara , Cassatella Marco A. , Bazzoni Flavia
Published: October 2007

We have recently reported that the ability of IL‐10 to rapidly exert its anti‐inflammatory effects on human neutrophils is dependent upon exposure of these cells to LPS for at least 3–4 h. Here, we demonstrate that, in neutrophils "preconditioned" by LPS, IL‐10 primarily targets the transcription of TNF‐α, CXCL8 and IL‐1ra genes, as revealed by primary transcript real‐time RT‐PCR. We also show that IL‐10‐induced transcriptional repression of TNF‐α and CXCL8 genes consists of two distinct phases: an early one, occurring rapidly and in a protein synthesis‐independent manner, followed by a second phase, more delayed and dependent on protein synthesis. Interestingly, the protein synthesis dependence of the latter phase coincides with a reduced ability of IL‐10 to induce STAT3 tyrosine phosphorylation. Importantly, inhibition of IL‐10‐induced STAT3 activation and IL‐10‐suppressive action by a prolonged exposure to cycloheximide (CHX) was observed to occur also in human monocytes and was caused by a defective IL‐10‐mediated activation of Jak1 and Tyk2 kinases. Taken together, our findings suggest that CHX interferes with the IL‐10‐mediated intracellular signaling pathway by interrupting events upstream of STAT3 activation. These data question the concept of the requirement of an IL‐10‐induced mediator as the unique mechanism to execute IL‐10 anti‐inflammatory program.
Determination of additives and organic contaminants in food by CE and CEC
Authors: Boyce Mary C.
Published: October 2007

The application of CE to the analysis of additives and organic contaminants in food since 2001 has been reviewed. Additives included in the review are dyes, preservatives, antioxidants and sweeteners. Organic contaminants included in the review are pesticides, antibiotics and those produced during processing or cooking food. The review highlights the strategies and approaches adopted in making CE suitable for the determination of analytes at residue level and in complicated matrices.
Epigenetic control of plant stress response
Authors: Boyko Alex , Kovalchuk Igor
Published: October 2007

Living organisms have the clearly defined strategies of stress response. These strategies are predefined by a genetic make‐up of the organism and depend on a complex regulatory network of molecular interactions. Although in most cases, the plant response to stress based on the mechanisms of tolerance, resistance, and avoidance has clearly defined metabolic pathways, the ability to acclimate/adapt after a single generation exposure previously observed in several studies (Boyko A et al. [2007]: Nucleic Acids Res 35:1714–1725; Boyko and Kovalchuk, unpublished data), represents an interesting phenomenon that cannot be explained by Mendelian genetics. The latest findings in the field of epigenetics and the process of a reversible control over gene expression and inheritance lead to believe that organisms, especially plants, may have a flexible short‐term strategy of the response to stress. Indeed, the organisms that can modify gene expression reversibly have an advantage in evolutionary terms, since they can avoid unnecessary excessive rearrangements and population diversification. This review covers various epigenetic processes involved in plant stress response. We focus on the mechanisms of DNA methylation and histone modifications responsible for the protection of somatic cells and inheritance of stress memories. Environ. Mol. Mutagen., 2008. © 2007 Wiley‐Liss, Inc.
Slope–channel coupling between pipes, gullies and tributary channels in the Mocatán catchment badlands, Southeast Spain
Authors: Faulkner H. , Alexander R. , Zukowskyj P.
Published: October 2007

The dispersive nature of the highly sodic silts of the Triassic‐rich unit of the Góchar formation plays a fundamental role in the erosion of the Mocatán catchment badlands in Almería, where a rejuvenating pipe and incised channel network is rapidly evacuating slope materials. Referring to concepts of medium‐ and long‐term landscape evolution, and incorporating contemporary thoughts on the role of connectivity in system evolution from the geomorphological literature, this paper attempts to develop a conceptual model of the way geologic, topographic, material property and ecological factors combine to explain the complex geomorphological evolution of the site.

An electronic distance measurement (EDM) survey was undertaken using a Leica TC3100, to produce a detailed topographic map. This database was supplemented by geomorphological, geological and ecological data derived from ground survey and remote sensing, and further morphometric analysis undertaken. Preferred orientations of channel segments, and the topographic distribution of pipe‐roof‐collapse features and outfalls in relation to known stratigraphic controls, suggests that, once coupled to the slope‐base channel, pipe networks develop in a systematic, sequential way. A wave of incision moving up the main channel reconnects channels with slopes, and the resulting increased hydraulic gradients on sideslopes encourage extensive deep pipe development for the first time in these materials. Once major pipe development is possible, three‐dimensional pipe networks enlarge and then collapse to form an extensive, partially coupled steep‐sided gully network. From this perspective, the coupling of the pipe to a rejuvenating channel is a significant intrinsic threshold event and the main reason that badlands have developed locally in these dispersive materials. It is concluded that erosion in this landscape will only be suppressed after a considerable period of slope‐base stability, which could allow a gradual loss of sodium from the surface by leaching or organic exchanges. Both theoretical and management implications are explored. Copyright © 2007 John Wiley & Sons, Ltd.
Probabilistic approach to voltage stability analysis with load uncertainty considered
Authors: Wu B. , Zhang Y. , Chen M. J.
Published: October 2007

This paper proposes a new probabilistic assessment algorithm of voltage stability based on Monte‐Carlo simulation and modal analysis considering uncertainty of the load level and load parameters. By Monte‐Carlo sampling, the bus load level is determined according to the forecasted bus load curve of a research period. The coefficients of the load polynomials, which include induction motors, are treated as random variables with normal distribution. A technique of normal distribution sampling is utilized to simulate these coefficients uncertainty. Voltage stability is evaluated in the form of indices such as the expected maximum loadability and the statistics of system participations, which are obtained from modal analysis near the point of collapse. A case study of the IEEE 118‐node system is given to demonstrate the validity of the proposed algorithm, and the effects of load uncertainty and the proportion of motors on probabilistic assessment of voltage stability are investigated. Copyright © 2007 John Wiley & Sons, Ltd.
New formulation and analysis of the system planning expansion model
Authors: Sadegheih A.
Published: October 2007

In this paper, an electrical power transmission network planning expansion is formulated for mixed‐integer programming, a genetic algorithm and tabu search (TS). Compared with other optimisation methods, GA's are suitable for traversing large search spaces since they can do this relatively rapidly and because the use of mutation diverts the method away from local minima, which will tend to become more common as the search space increases in size. GA's give an excellent trade‐off between solution quality and computing time and flexibility for taking into account specific constraints in real situations. TS has emerged as a new, highly efficient, search paradigm for finding quality solutions to combinatorial problems. It is characterised by gathering knowledge during the search, and subsequently profiting from this knowledge. The attractiveness of the technique comes from its ability to escape local optimality. The cost function of this problem consists of the capital investment cost in discrete form, the cost of transmission losses and the power generation costs. The DC load flow equations for the network are embedded in the constraints of the mathematical model to avoid sub‐optimal solutions that can arise if the enforcement of such constraints is done in an indirect way. The solution of the model gives the best line additions, and also provides information regarding the optimal generation at each generation point. This method of solution is demonstrated on the expansion of a 10 bus‐bar system to 18 bus‐bars. Finally, an empirical analysis of the effects of parameter values on genetic algorithm performance is tested. Copyright © 2007 John Wiley & Sons, Ltd.
Distortions in Electrochemical Impedance Spectroscopy Measurements Using 3‐Electrode Methods in SOFC. II. Effect of Electrode Activity and Relaxation Times
Authors: Cimenti M. , Birss V. I. , Hill J. M.
Published: October 2007

The 3‐electrode configuration is commonly applied to quantify the overpotential of anodes or cathodes in solid‐oxide fuel cells (SOFC). In this type of set‐up, a reference electrode (RE) is used to isolate the potential loss of one electrode from that of the entire cell; however, erroneous results can be obtained whenever the RE does not precisely separate the potential drop between the two active electrodes. In this study, we present the results of a theoretical and experimental analysis focused on verifying the effectiveness of the 3‐electrode configuration in electrochemical impedance spectroscopy measurements for the kinetic characterisation of SOFC electrode reactions. The focus of this paper is on the distortion of impedance measurements caused by differences in the area‐specific polarisation resistance and impedance time constants of the working and counter electrodes. The results obtained numerically and experimentally, both for planar and tubular SOFC cell geometries, prove the reliability of the theoretical model used. From the systematic simulation presented here and in our previous work, it was possible to formulate general guidelines for the design of 3‐electrode experimental SOFC. The theoretical model used here can also be used to verify the consistency of EIS measurements obtained with thin planar cells.
Investigation of the Ethanol Electro‐Oxidation in Alkaline Membrane Electrode Assembly by Differential Electrochemical Mass Spectrometry
Authors: Rao V. , Hariyanto  , Cremers C. , Stimming U.
Published: October 2007

The fuel cell differential electrochemical mass spectrometry (FC‐DEMS) measurements were performed for studying the ethanol oxidation reaction (EOR), using alkaline membrane electrode assemblies (MEAs) made up of nanoparticle Pt catalyst and alkaline polymeric membranes. The obtained results indicate that in an alkaline medium, ethanol undergoes significantly more complete electro‐oxidation to CO2 than in an acidic MEA using the same Pt anode. The CO2 current efficiency (CCE) can be compared for acidic and alkaline MEA with similar electrochemical active area on the anode side. The CCE estimated, in case of alkaline MEA with Pt anode, is around 55% at 0.8 V/RHE, 60 °C and 0.1 M ethanol. In comparison, under similar conditions, acidic MEAs using the same anode catalyst show only 2% CCE. This might indicate that the C–C bond scission rates are much higher in alkaline media. However, the mechanism of ethanol oxidation in alkaline media is not exactly known. CO2 produced in electrochemical reaction forms soluble carbonates in the presence of aqueous alkaline electrolyte. This makes it difficult to study ethanol oxidation in alkaline media using FTIR or model DEMS systems. The alkaline polymer electrolyte membranes as used in this study for making alkaline MEAs provide an important opportunity to observe CO2 produced during EOR using FC‐DEMS system.
Robust estimation and testing of haplotype effects in case‐control studies
Authors: Allen Andrew S. , Satten Glen A.
Published: October 2007

Haplotype‐based analyses are thought to play a major role in the study of common complex diseases. This has led to the development of a variety of statistical methods for detecting disease‐haplotype associations from case‐control study data. However, haplotype phase is often uncertain when only genotype data is available. Methods that account for haplotype ambiguity by modeling the distribution of haplotypes can, if this distribution is misspecified, lead to substantial bias in parameter estimates even when complete genotype data is available. Here we study estimators that can be derived from score functions of appropriate likelihoods. We use the efficient score approach to estimation in the presence of nuisance parameters to a derive novel estimators that are robust to the haplotype distribution. We establish key relationships between estimators and study their empirical performance via simulation.Genet. Epidemiol. 2007. Published 2007 Wiley‐Liss, Inc.
Medication use in nursing home residents with advanced dementia
Authors: Blass David M. , Black Betty S. , Phillips Hilary , Finucane Thomas , Baker Alva , Loreck David , Rabins Peter V.
Published: October 2007

Objective

To describe medication usage in nursing home residents with advanced dementia, to identify how this usage changed as patients advanced towards death, and to identify correlates of increased medication usage.

Methods

Prospective cohort study (CareAD) during which data on medication prescription were extracted from medical records at regular intervals using standardized extraction procedures.

Results

Patients (n = 125) were prescribed a mean of 14.6 medications during the 6 months prior to study enrollment. In a subgroup of patients who died during the study (n = 88), as the time of death approached, the total number of medications prescribed did not vary but the types of medications prescribed did change, with an increase in palliative medications such as opiate analgesics and a decrease in other medication classes such as antibiotics, anti‐dementia agents, cardiovascular agents, and psychotropic agents, among others. In linear regression analyses, total medication prescription at study entry was associated with study site, antibiotic treatment, presence of cardiovascular disease, and treatment of gastrointestinal or dermatological conditions.

Conclusions

Nursing home residents with advanced dementia are prescribed a large number of medications from numerous medication classes and prescribing patterns change over time. Further study is needed to determine the ideal approach to treating chronic medical problems at the end of life in this patient population. Copyright © 2007 John Wiley & Sons, Ltd.
One extra month of depression: the effects of caregiving on depression outcomes in the IMPACT trial
Authors: Thompson Alex , Fan Ming‐Yu , Unützer Jürgen , Katon Wayne
Published: October 2007

Background

Depression occurs in 5–10% of older adults and there are nearly 6 million informal caregivers aged 65 or older. Prior research has focused on vulnerability to psychological distress in caregivers. Research has not addressed the caregiving burden of depressed elderly patients or how that burden affects depression treatment outcomes.

Aims

To describe the self‐reported caregiving burden in a large, representative cohort of depressed elderly patients and compare depression treatment outcomes between caregivers and non‐caregivers.

Methods

Univariate and multiple regression analyses were performed comparing 24‐month depression outcomes (measured as depression free days) in those providing care at any time over the 24‐month trial to those who never reported a caregiving burden.

Results

At 3, 6, 12, 18, and 24 months, nearly 10% of cohabitating elderly depressed patients provided care for basic activities such as bathing or dressing while nearly 20% reported providing care for other activities such as making phone calls or taking medication. Over 24 months, after adjusting for marital status, intervention status, and number of medical comorbidities, those reporting any caregiving burden had over 30 more days with depression compared to those with no caregiving burden. The IMPACT collaborative care model did not modify the effect of caregiving on depression outcomes.

Conclusion

Caregiving is common in depressed older adults and appears to affect response to depression treatment. In the future, interventions for depressed older adults should consider and specifically address caregiving activities in addition to specific depression treatment. Copyright © 2007 John Wiley & Sons, Ltd.
Price increase causes fewer sales of factory‐made cigarettes and higher sales of cheaper loose tobacco in Germany
Authors: Hanewinkel Reiner , Radden Christian , Rosenkranz Tobias
Published: October 2007

Aim of this study is the analysis of the price responsiveness of demand for cigarettes and loose tobacco in Germany over the period 1991–2006. In this period the average consumption of all kinds of cigarettes per capita (German population ≥ 15 years) declined from 634 pieces/quarter to 457pieces/quarter (−28%). Consumption of factory‐made cigarettes decreased from about 545 pieces/quarter to 330 pieces/quarter in 2006 (−39%). In the same time consumption of self‐made cigarettes increased from 89 pieces/quarter to 127 pieces/quarter (+42%). A one Euro Cent increase in price is associated with 28 cigarettes of all kinds consumed less per quarter. Data indicate that the different types of cigarettes are substitutes, e.g. there is evidence for a positive relationship between the price of factory‐made cigarettes and the consumption of hand‐made cigarettes. Thus, the increase in such consumption is rather driven by a positive cross‐price effect of 17.01. Data indicate additionally an overall decrease in the cigarette consumption and a partial switch to cheaper loose tobacco. The availability of low‐taxed loose tobacco may undermine the public health benefits of higher cigarette prices. Price differentials between tobacco products should be reduced in order to maximize the public health benefits of high cigarette prices. Copyright © 2007 John Wiley & Sons, Ltd.
Laminin-5 stimulates hepatocellular carcinoma growth through a different function of α6β4 and α3β1 integrins
Authors: Bergamini Carlo , Sgarra Concetta , Trerotoli Paolo , Lupo Luigi , Azzariti Amalia , Antonaci Salvatore , Giannelli Gianluigi
Published: October 2007

Hepatocellular carcinoma (HCC) growth severely affects prognosis. Ki-67, a known marker of cell proliferation, is a negative prognostic factor in HCC. Growth factors such as the epidermal growth factor (EGF) induce HCC cell proliferation but do not explain the great heterogeneity of HCC growth. Laminin-5 (Ln-5) is an extracellular matrix protein (ECM) present in the tissue microenvironment of HCC. The two main receptors for Ln-5, integrins α3β1 and α6β4, are expressed on the cell surface of HCC cells. The aim of this study is to investigate an alternative mechanism of HCC growth whereby Ln-5 promotes HCC cell proliferation through α3β1 and α6β4. HCC tissues containing Ln-5 display a larger diameter and higher number of positive cells for Ki-67, a well known proliferative index, as determined by double immunofluorescence staining and real-time PCR on microdissected tissues.

In vitro

, Ln-5, but not collagen I, collagen IV or fibronectin, induces proliferation as much as EGF does, via Erk phosphorylation as a consequence of β4 integrin phosphorylation. However, the two HCC cell lines do not proliferate in presence of Ln-5 despite β4 integrin and Erk1/2 activation. After transfection with α3 integrin, in the presence of Ln-5 one of these HCC cell lines acquires a proliferative activity whereas one of the proliferative HCC cell lines, knocked-down for α3 integrin, loses its proliferative activity.

Conclusions:

Our study suggests a new mechanism of HCC growth whereby Ln-5 stimulates proliferation via a different function of α6β4 and α3β1. (Hepatology 2007.)
Flavonoid Glycosides from Ranunculus chinensisBge.
Authors: Zou Yan‐Ping , Tan Chang‐Heng , Wang Bao‐De , Jiang Shan‐Hao , Zhu Da‐Yuan
Published: October 2007

Four new flavonoid glycosides, 3‐O‐[α‐L‐arabinopyranosyl‐(1→2)‐β‐D‐galactopyranosyl]‐7‐O‐β‐D‐glucopyranosylkaempferol (1), 3‐O‐(α‐L‐arabinopyranosyl‐(1→2)‐{4‐O‐[(E)‐caffeoyl]‐β‐D‐galactopyranosyl})‐7‐O‐β‐D‐glucopyranosylquercetin (2), 3‐O‐{2‐O‐[(E)‐caffeoyl]‐α‐L‐arabinopyranosyl‐(1→2)‐β‐D‐galactopyranosyl}‐7‐O‐β‐D‐glucopyranosylkaemperfol (3), and 3‐O‐{2‐O‐[(E)‐caffeoyl]‐α‐L‐arabinopyranosyl‐(1→2)‐β‐D‐galactopyranosyl}kaempferol (4), together with two known compounds were isolated from the aerial parts of Ranunculus chinensis Bge. The structures of the new glycosides were determined on the basis of spectroscopic analysis, including 1D‐ and 2D‐NMR, and ESI‐MS techniques, and chemical methods.
Synthesis and Hybridization Properties of Oligodeoxynucleotides with Long‐Chain Linkers
Authors: Seio Kohji , Terada Takeshi , Mizuta Masahiro , Ohkubo Akihiro , Taguchi Haruhiko , Sekine Mitsuo
Published: October 2007

New oligonucleotides with a long‐chain linker (6,9‐dioxa‐3,12‐diazatetradecane‐1,14‐diyl) in their backbone were synthesized, and their hybridization properties were studied by measurement of their Tm curves and fluorescence spectra. The Tm analyses revealed that these oligonucleotides could bind to their complementary strands despite the presence of the long‐chain linker. We also demonstrated interesting fluorescence properties of oligodeoxynucleotides with an anthracen‐9‐ylmethyl group on one of the two N‐atoms in the long‐chain linker. The fluorescence intensity of these oligonucleotides increased upon their hybridization to the complementary strands and was sensitive to the presence of the mismatch base pairs at a specific position.
Folding–Unfolding Equilibrium of a Methylidene‐Substituted β‐Peptide
Authors: Schmid Nathan , Zagrovic Bojan , van Gunsteren Wilfred F.
Published: October 2007

β‐Peptides possess the ability to fold into secondary structure elements, and this property, together with resistance to biodegradation, makes these compounds interesting for pharmaceutical applications. Recently, a novel class of β‐peptides containing methylidene moieties was described. The GROMOS 53A6 force field was used to simulate the folding equilibrium of a β3‐hexapeptide with methylidene (CH2) groups at all six CA‐atoms. Due to the rotational barriers induced by these methylidene groups, the helical secondary‐structure elements, normally found in β3‐peptides, are disfavored in this molecule. Simulations, started from fully extended and 314‐helical conformations, showed that the molecule adopts a complete 28‐helix for ca. 5% of the time and partial 28‐helical conformations for ca. 20% of the time. Yet, as suggested by experiments, the folding equilibrium is dominated by unfolded conformations.
Tirucallane Triterpenoid Saponins from Munronia delavayiFranch
Authors: Cai Xiang‐Hai , Du Zhi‐Zhi , Luo Xiao‐Dong
Published: October 2007

Four new tirucallane triterpenoid saponins, named munronosides I–IV (2–5), along with three known triterpenoids, sapelin B (1), melianodiol, and (3β)‐22,23‐epoxytirucall‐7‐ene‐3,24,25‐triol, were isolated from the EtOH extract of the whole plants of Munronia delavayi Franch by chromatographic methods. On the basis of spectroscopic evidences, the structures of 2–5 were elucidated as (20S,23R,24S)‐21,25‐epoxy‐29‐{{O‐β‐d‐glucopyranosyl‐(1→3)‐O‐[α‐l‐rhamnopyranosyl‐(1→6)]‐β‐d‐glucopyranosyl}oxy}‐23,24‐dihydroxytirucall‐7‐ene‐3,21‐dione (2), (3β,20S,23R,24S)‐21,25‐epoxy‐29‐{{O‐β‐d‐glucopyranosyl‐(1→3)‐O‐[α‐l‐rhamnopyranosyl‐(1→6)]‐β‐d‐glucopyranosyl}oxy}‐3,23,24‐trihydroxytirucall‐7‐en‐21‐one (3), (20S,23R,24S)‐24‐(acetyloxy)‐21,25‐epoxy‐29‐{{O‐β‐d‐glucopyranosyl‐(1→3)‐O‐[α‐l‐rhamnopyranosyl‐(1→6)]‐β‐d‐glucopyranosyl}oxy}‐23‐hydroxytirucall‐7‐ene‐3,21‐dione (4), and (3β,20S,23R,24S)‐24‐(acetyloxy)‐21,25‐epoxy‐29‐{{O‐β‐d‐glucopyranosyl‐(1→3)‐O‐[α‐l‐rhamnopyranosyl‐(1→6)]‐β‐d‐glucopyranosyl}oxy}‐3,23‐dihydroxytirucall‐7‐en‐21‐one (5).
CD133 negative glioma cells form tumors in nude rats and give rise to CD133 positive cells
Authors: Wang Jian , Sakariassen Per Ø. , Tsinkalovsky Oleg , Immervoll Heike , Bøe Stig Ove , Svendsen Agnete , Prestegarden Lars , Røsland Gro , Thorsen Frits , Stuhr Linda , Molven Anders , Bjerkvig Rolf , Enger Per Ø.
Published: October 2007

CD133 is a cell surface marker expressed on progenitors of haematopoietic and endothelial cell lineages. Moreover, several studies have identified CD133 as a marker of brain tumor‐initiating cells. In this study, human glioblastoma multiforme biopsies were engrafted intracerebrally into nude rats. The resulting tumors were serially passaged in vivo, and monitored by magnetic resonance imaging. CD133 expression was analyzed at various passages. Tumors initiated directly from the biopsies expressed little or no CD133, and showed no contrast enhancement suggesting an intact blood‐brain barrier. During passaging, the tumors gradually displayed more contrast enhancement, increased angiogenesis and a shorter survival. Real‐time qPCR and immunoblots showed that this was accompanied by increased CD133 expression. Primary biopsy spheroids and xenograft tumors were subsequently dissociated and flow sorted into CD133 negative and CD133 positive cell populations. Both populations incorporated BrdU in cell culture, and expressed the neural precursor marker nestin. Notably, CD133 negative cells derived from 6 different patients were tumorgenic when implanted into the rat brains. For 3 of these patients, analysis showed that the resulting tumors contained CD133 positive cells. In conclusion, we show that CD133 negative glioma cells are tumorgenic in nude rats, and that CD133 positive cells can be obtained from these tumors. Upon passaging of the tumors in vivo, CD133 expression is upregulated, coinciding with the onset of angiogenesis and a shorter survival. Thus, our findings do not suggest that CD133 expression is required for brain tumor initiation, but that it may be involved during brain tumor progression. © 2007 Wiley‐Liss, Inc.