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Short Review (short + review)
Selected AbstractsThe Physiological Basis of Uterine Contractility: A Short ReviewEXPERIMENTAL PHYSIOLOGY, Issue 2 2001S. Wray In this review we discuss our current understanding of the cellular basis of uterine contractility, highlighting those areas requiring further study. It is clear that the basic processes of excitation-contraction coupling lie within the myometrial cell, and that these may be modified by agonists. Pacemaker acitivity, however, remains a mystery. The contribution of extracellular calcium entry to contraction is shown to be vital, whilst the role of the sarcoplasmic reticulum remains controversial. Much current experimental focus is on pathways controlling and regulating contraction, and we discuss sensitisation mechanisms and question their role in intact uterine preparations. [source] Information derived from sensitization test methods: test sensitivity, false positives and false negativesCONTACT DERMATITIS, Issue 1 2007David A. Basketter Predictive toxicology tests for the prospective identification of skin-sensitizing chemicals are well known and have been used for many years. However, of these, only the local lymph node assay (LLNA) has actually undergone formal independent assessment to determine the accuracy of the predictions, particularly with respect to the likelihood of false positives and false negatives. Often, efforts to increase the sensitivity of a test (reducing false negatives) tend to increase the number of false positives. In this short review, these issues are discussed in particular relation to the 3 predictive tests available in regulatory toxicology, the guinea-pig maximization test, the occluded patch test of Buehler and the LLNA. A key perspective is that no predictive test is without limitations; having a good appreciation of these limitations is necessary for making the best use of the information derived from these methods. [source] Radiation induced modification of impurity-related point defects in crystalline quartz , a reviewCRYSTAL RESEARCH AND TECHNOLOGY, Issue 7 2006Harish Bahadur Abstract This article presents a short review of impurity-related point defects in crystalline quartz and their radiation induced modifications. In particular, a discussion has been presented on some of the prominent aluminum related alkali and proton compensated centers. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Contribution to the stability analysis of the dewetted Bridgman growth under microgravity conditionsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 6 2004L. Bizet Abstract Experimental observations show that the gap between the sample and the crucible, commonly obtained after solidification in microgravity, is remarkably stable. With the aim to understand the reason of this stability, the dewetting phenomenon is studied by Lyapunov's method. After a short review of the existing mechanisms leading to dewetting, the open smooth crucible configuration is chosen as the most representative. The analytical stability analysis, taking into account geometrical and thermal effects, performed under some boundary heat transfer approximations, shows that, in most cases, the dewetting process is intrinsically stable. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] From segment to somite: Segmentation to epithelialization analyzed within quantitative frameworksDEVELOPMENTAL DYNAMICS, Issue 6 2007Paul M. Kulesa Abstract One of the most visually striking patterns in the early developing embryo is somite segmentation. Somites form as repeated, periodic structures in pairs along nearly the entire caudal vertebrate axis. The morphological process involves short- and long-range signals that drive cell rearrangements and cell shaping to create discrete, epithelialized segments. Key to developing novel strategies to prevent somite birth defects that involve axial bone and skeletal muscle development is understanding how the molecular choreography is coordinated across multiple spatial scales and in a repeating temporal manner. Mathematical models have emerged as useful tools to integrate spatiotemporal data and simulate model mechanisms to provide unique insights into somite pattern formation. In this short review, we present two quantitative frameworks that address the morphogenesis from segment to somite and discuss recent data of segmentation and epithelialization. Developmental Dynamics 236:1392,1402, 2007. © 2007 Wiley-Liss, Inc. [source] Electrochemical Sensors Based on Carbon NanotubesELECTROANALYSIS, Issue 23 2002Qiang Zhao Abstract Carbon nanotubes are attractive new materials. It has been about a decade since carbon nanotubes were discovered. Carbon nanotubes have many outstanding properties and have many practical or potential applications. In this short review we introduce recent advances in carbon nanotubes as potential material for electrochemical sensors. The advantages of carbon nanotubes as sensors are discussed along with future prospects. [source] Prevention of embolic stroke by catheter ablation of atrial fibrillationEUROPEAN JOURNAL OF NEUROLOGY, Issue 12 2008C. Stöllberger Background and purpose:, Radiofrequency-catheter-ablation of atrial fibrillation is now commonly performed. Aim of this short review is to summarize questions and uncertainties concerning radiofrequency ablation of atrial fibrillation with respect to therapeutic mechanisms, long-term efficacy and stroke-prevention. Results:, The majority of atrial fibrillation patients is too old for radiofrequency ablation. Candidates for radiofrequency ablation belong to a subgroup with a low embolic risk. The radiofrequency ablation procedure itself may increase the embolic risk, and at present it is uncertain how long this embolic risk persists after the procedure. Conclusion:, We doubt if radiofrequency ablation prevents embolism in atrial fibrillation. [source] A role for glutamate transmission in addiction to psychostimulantsADDICTION BIOLOGY, Issue 3 2000Peter W. Kalivas Psychostimulant addiction results in the emergence of undesirable behaviors such as drug craving and paranoia. Using animal models of addiction the neurobiological substrates mediating these behaviors have been examined. Studies have focused on cellular adaptations within the motive circuit that contains the nucleus accumbens, ventral tegmental area, ventral pallidum and prefrontal cortex. While long-term alterations in dopamine transmission have been clearly characterized, more recent studies reveal that important neuroadaptations are also produced in glutamate transmission. This short review provides a description of these neuroadaptations and a discussion of how these psychostimulant-induced changes may synergize to elicit addiction-related behaviors. [source] SK channels and the varieties of slow after-hyperpolarizations in neuronsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2003Fivos Vogalis Abstract Action potentials and associated Ca2+ influx can be followed by slow after-hyperpolarizations (sAHPs) caused by a voltage-insensitive, Ca2+ -dependent K+ current. Slow AHPs are a widespread phenomenon in mammalian (including human) neurons and are present in both peripheral and central nervous systems. Although, the molecular identity of ion channels responsible for common membrane potential mechanisms has been largely determined, the nature of the channels that underlie the sAHPs in neurons, both in the brain and in the periphery, remains unresolved. This short review discusses why there is no clear molecular candidate for sAHPs. [source] The mesenchymal component of hair follicle neogenesis: background, methods and molecular characterizationEXPERIMENTAL DERMATOLOGY, Issue 2 2010Manabu Ohyama Please cite this paper as: The mesenchymal component of hair follicle neogenesis: background, methods and molecular characterization. Experimental Dermatology 2010; 19: 89,99. Abstract:, Hair follicle morphogenesis and regeneration occur by an extensive and collaborative crosstalk between epithelial and mesenchymal skin components. A series of pioneering studies, which revealed an indispensable role of follicular dermal papilla and dermal sheath cells in this crosstalk, has led workers in the field to study in detail the anatomical distribution, functional properties, and molecular signature of the trichogenic dermal cells. The purpose of this paper was to provide a practical summary of the development and recent advances in the study of trichogenic dermal cells. Following a short review of the relevant literature, the methods for isolating and culturing these cells are summarized. Next, the bioassays, both in vivo and in vitro, that enable the evaluation of trichogenic properties of tested dermal cells are described in detail. A list of trichogenic molecular markers identified by those assays is also provided. Finally, this methods review is completed by defining some of the major questions needing resolution. [source] The rapidly adapting receptors in mammalian airways and their responses to changes in extravascular fluid volumeEXPERIMENTAL PHYSIOLOGY, Issue 4 2006C. Tissa Kappagoda In this short review, we shall focus on some recent findings on the physiological stimulus for the rapidly adapting receptors (RAR) of the airways. They are readily activated by a sustained inflation of the lungs and they are usually identified by their rapid adaptation to this stimulus. They are also activated by both tactile stimuli and irritant gases applied to the epithelium of the airways. The investigations reviewed here suggest that these receptors are activated by changes in extravascular fluid volume. The principal factors governing fluid flux from the microcirculation are identified in the Starling equation. These are the hydrostatic pressure, plasma oncotic pressure and capillary permeability. Findings from recent studies suggest that all these factors increase the activity of RAR. In addition, these receptors are also activated by obstruction of lymph drainage from the lung. Evidence is presented to show that manipulation of Starling forces also increases the extravascular fluid volume of the airways in areas where the RAR are located. On the basis of these findings, it is suggested that, along with mechanosensitivity to stimuli such as stretch, inflation and deflation, another physiological stimulus to the RAR is a change in extravascular fluid volume in the regions of the airways where these receptors are located. [source] Bacteria in the cold deep-sea benthic boundary layer and sediment,water interface of the NE AtlanticFEMS MICROBIOLOGY ECOLOGY, Issue 2 2000Carol Turley Abstract This is a short review of the current understanding of the role of microorganisms in the biogeochemistry in the deep-sea benthic boundary layer (BBL) and sediment,water interface (SWI) of the NE Atlantic, the gaps in our knowledge and some suggestions of future directions. The BBL is the layer of water, often tens of meters thick, adjacent to the sea bed and with homogenous properties of temperature and salinity, which sometimes contains resuspended detrital particles. The SWI is the bioreactive interface between the water column and the upper 1 cm of sediment and can include a large layer of detrital material composed of aggregates that have sedimented from the upper mixed layer of the ocean. This material is biologically transformed, over a wide range of time scales, eventually forming the sedimentary record. To understand the microbial ecology of deep-sea bacteria, we need to appreciate the food supply in the upper ocean, its packaging, passage and transformation during the delivery to the sea bed, the seasonality of variability of the supply and the environmental conditions under which the deep-sea bacteria grow. We also need to put into a microbial context recent geochemical findings of vast reservoirs of intrinsically labile organic material sorped onto sediments. These may well become desorped, and once again available to microorganisms, during resuspension events caused by deep ocean currents. As biotechnologists apply their tools in the deep oceans in search of unique bacteria, an increasing knowledge and understanding of the natural processes undertaken and environmental conditions experienced by deep-sea bacteria will facilitate this exploitation. [source] Sigma receptors: from discovery to highlights of their implications in the cardiovascular systemFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 1 2002Laurent Monassier Sigma receptors are the targets of many ligands, of which some (the haloperidol for instance) are psychoactive, and of substances known to have antiarrhythmic effects (amiodarone and clofilium). They are involved in a variety of cardiovascular functions, such as the regulation of cardiac contractility and rhythm and the regulation of coronary and peripheral arterial vasomotricity. This short review will focus on some aspects regarding the ligands, the binding sites, the intracellular coupling and the cardiovascular functions of these enigmatic receptors. [source] Roles of partly unfolded conformations in macromolecular self-assemblyGENES TO CELLS, Issue 1 2001Keiichi Namba From genes to cells there are many steps of hierarchical increments in building up complex frameworks that provide intricate networks of macromolecular interactions, through which cellular activities such as gene expression, signal processing, energy transduction and material conversion are dynamically organized and regulated. The self-assembly of macromolecules into large complexes is one such important step, but this process is by no means a simple aggregation of macromolecules with predefined, rigid complementary structures. In many cases the component molecules undergo either domain rearrangements or folding of disordered portions, which occurs only following binding to their correct partners. The partial disorder is used in some cases to prevent spontaneous assembly at inappropriate times or locations. It is also often used for finely tuning the equilibrium and activation energy of reversible binding. In other cases, such as protein translocation across membranes, an unfolded terminus appears to be the prerequisite for the process as an initiation signal, as well as the physical necessity to be taken into narrow channels. Self-assembly processes of viruses and bacterial flagella are typical examples where the induced folding of disordered chains plays a key role in regulating the addition of new components to a growing assembly. Various aspects of mechanistic roles of natively unfolded conformations of proteins are overviewed and discussed in this short review. [source] A Surface-Based Approach to Measuring Spatial SegregationGEOGRAPHICAL ANALYSIS, Issue 2 2007David O'Sullivan Quantitative indices of residential segregation have been with us for half a century, but suffer significant limitations. While useful for comparison among regions, summary indices fail to reveal spatial aspects of segregation. Such measures generally consider only the population mix within zones, not between them. Zone boundaries are treated as impenetrable barriers to interaction between population subgroups, so that measurement of segregation is constrained by the zoning system, which bears no necessary relation to interaction among population subgroups. A segregation measurement approach less constrained by the chosen zoning system, which enables visualization of segregation levels at the local scale and accounts for the spatial dimension of segregation, is required. We propose a kernel density estimation approach to model spatial aspects of segregation. This provides an explicitly geographical framework for modeling and visualizing local spatial segregation. The density estimation approach lends itself to development of an index of spatial segregation with the advantage of functional compatibility with the most widely used index of segregation (the dissimilarity index D). We provide a short review of the literature on measuring segregation, briefly describe the kernel density estimation method, and illustrate how the method can be used for measuring segregation. Examples using a simulated landscape and two empirical cases in Washington, DC and Philadelphia, PA are presented. [source] Ankerung im Untertagebau , Entwicklungen in Theorie und PraxisGEOMECHANICS AND TUNNELLING, Issue 5 2008Stefan Kainrath-Reumayer Dipl.-Ing. Die systematische Ankerung des Gebirges stellt ein wesentliches Verfahren zur Stabilisierung unterirdischer Hohlraumbauten dar. Die geschichtliche Entwicklung verschiedener Ankersysteme wird kurz vorgestellt und Unterteilungsmöglichkeiten werden aufgezeigt. Unterschiedliche Ansätze der Systemankerungen in analytischen und numerischen Berechnungen werden mit der diskreten Modellierung des Gesamtssystems in numerischen Berechnungen mit FLAC3D verglichen. Der Einfluss von Systemankerungen auf das Systemverhalten ist von einer Reihe von Randbedingungen abhängig, der Erfolg der Anwendung oftmals von den verwendeten Ankersystemen. Extreme Spannungszustände im Gebirge stellen hohe Anforderungen an die Methodik der Gebirgsankerung in Untertagebauwerken, die mit den herkömmlichen Ankerungssystemen nur eher unzufriedenstellend zu bewältigen sind. In Abhängigkeit von den Eigenschaften des Gebirges ist unter solch hohen, die Festigkeit des intakten Gebirges meist bereits überschreitenden Spannungszuständen mit großen Verschiebungen, Stabilitätsproblemen sowie Bergschlagphänomenen zu rechnen. Um diesen Anforderungen bestmöglich gerecht zu werden, wird ein neuartiger, energieabsorbierender Ankertyp "Roofex" vorgestellt, der sowohl unter langsam kriechenden, statischen, wie auch abrupten, dynamischen Beanspruchungen einen kontrollierbaren und konstanten Widerstand entlang eines definierten Gleitwegs aufweist. Rock bolting in subsurface constructions , developments in theory and praxis The systematic bolting of rock is a key support element in NATM tunnelling. A short review on the historical development and methods of classification is presented. Different methods of implementation in analytical and numerical calculations are compared to the discrete modelling of the system via FLAC 3D. The influence of the systematic rock bolting to the system behaviour is dependent on many boundary conditions, the success often depends on the used rock bolting techniques. High rock mass stress conditions in underground excavations are serious challenges for rock bolting systems, where conventional bolting systems can only cope with in an rather unsatisfactory way. Depending on the rock mass conditions, high stresses, which mostly exceed already the intact rock mass strength, will lead to serious stability problems, high deformation rates and rockburst phenomena. To provide the mining and tunnelling industry with a rock reinforcement fixture that is better suited to mining with high stress conditions, Atlas Copco GDE designed a new, energy absorbing rock bolt "Roofex" that can accommodate both very large displacements (static yielding) and high energy release (dynamic rupture) in the rock mass by offering an accurate pre-set deformation behaviour. [source] Symposium in memory of Professor Inga Marie NilssonHAEMOPHILIA, Issue 4 2001Article first published online: 18 JUL 200 Professor Inga Marie Nilsson (1923,99) was a pioneer in the field of bleeding and thromboembolic disorders and made several major scientific contributions during her career. To honour her memory, colleagues from all over the world were invited to cover several aspects of haemostasis by giving state-of-the-art lectures at an international symposium in Malmö on September 22,23, 2000, chaired by Professors Lou Aledort and Erik Berntorp. Colleagues of Professor Nilsson in Malmö gave a short introduction to each topic. A short review of the meeting will be presented. [source] Internet-based information-seeking behaviour amongst doctors and nurses: a short review of the literatureHEALTH INFORMATION & LIBRARIES JOURNAL, Issue 1 2010Paula Younger Background:, Reviews of how doctors and nurses search for online information are relatively rare, particularly where research examines how they decide whether to use Internet-based resources. Original research into their online searching behaviour is also rare, particularly in real world clinical settings. as is original research into their online searching behaviour. This review collates some of the existing evidence, from 1995 to 2009. Objectives:, To establish whether there are any significant differences in the ways and reasons why doctors and nurses seek out online information; to establish how nurses and doctors locate information online; to establish whether any conclusions can be drawn from the existing evidence that might assist health and medical libraries in supporting users. Methods:, An initial scoping literature search was carried out on PubMed and CINAHL to identify existing reviews of the subject area and relevant original research between 1995 and 2009. Following refinement, further searches were carried out on Embase (Ovid), LISA and LISTA. Following the initial scoping search, two journals were identified as particularly relevant for further table of contents searching. Articles were exclused where the main focus was on patients searching for information or where the focus was the evaluation of online-based educational software or tutorials. Articles were included if they were review or meta-analysis articles, where they reported original research, and where the primary focus of the online search was for participants' ongoing Continuing Professional Development (CPD). The relevant articles are outlined, with details of numbers of participants, response rates, and the user groups. Results:, There appear to be no significant differences between the reasons why doctors and nurses seek online Internet-based evidence, or the ways in which they locate that evidence. Reasons for searching for information online are broadly the same: primarily patient care and CPD (Continuing Professional Development). The perceived barriers to accessing online information are the same in both groups. There is a lack of awareness of the library as a potential online information enabler. Conclusions:, Libraries need to examine their policy and practice to ensure that they facilitate access to online evidence-based information, particularly where users are geographically remote or based in the community rather than in a hospital setting. Librarians also need to take into account the fact that medical professionals on duty may not be able to take advantage of the academic model of online information research. Further research is recommended into the difference between the idealised academic model of searching and real world practicalities; and how other user groups search, for example patients. [source] Endocrine disruptors and male reproductive function , a short reviewINTERNATIONAL JOURNAL OF ANDROLOGY, Issue S2 2000Sin-Eng Chia Semen quality has decline in many countries over the last few decades. There has been an increase in the incidence of testicular cancer world-wide. The incidences of cryptorchidism and hypospadias have also increased in many countries. A biological plausible hypothesis has suggested that man-made chemicals act as endocrine disruptors resulting in altered development of the reproductive tract causing the observed effects. Endocrine disruptors include natural products, pharmaceuticals, industrial products and environmental pollutants. There are limitations in the current in vivo and in vitro assays for the assessment of endocrine disruptors. Epidemiological human studies are necessary to fill in the gap of knowledge. Based on the current knowledge, the impact of endocrine disruptors on the male reproductive function remain to be appreciated. [source] Early administration of ultraviolet treatment is effective in pegylated interferon alpha-induced severe acute exacerbation of psoriasis: a case report and short review of the literatureINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 1 2010N. S. Tekin No abstract is available for this article. [source] Optimal operation of CVT-based powertrainsINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 11 2001Rolf Pfiffner Abstract Continuously Variable Transmissions (CVTs) are considered by many as a promising contribution to the improvement of the fuel economy of passenger cars. This paper discusses the fuel-optimal operation of a CVT-equipped powertrain in stationary and in transient conditions. The well-known optimal solution in the stationary case will be given only a short review discussing the importance of a correct CVT efficiency model. For transient vehicle operation so far only heuristic control strategies are known. This work aims to fill this gap. After detailed modelling of the complete powertrain and the introduction of a meaningful cost function, the resulting nonlinear optimal control problem is solved. The optimization is carried out for two different engines: a conventional SI engine and a downsized supercharged (DSC) SI engine. Each can be considered as a typical representative of the corresponding engine class. In both cases the optimal solutions are shown to be superior to standard CVT control algorithms, yielding larger gains in fuel economy for DSC engines. The optimal feedforward controls are then approximated by suboptimal feedback controllers that realize almost the same benefits in fuel economy at a substantially reduced computational effort. Finally, it is shown how the well-known ,single track modified' control approach can be changed such that it produces the same results as the suboptimal controller. Copyright © 2001 John Wiley & Sons, Ltd. [source] Redox regulation of skeletal muscleIUBMB LIFE, Issue 8 2008Malcolm J. Jackson Abstract The potential deleterious roles of "oxidative stress" have been studied in skeletal muscle for over 30 years, but recent studies have identified that reactive oxygen species and nitric oxide generated by skeletal muscle can exert regulatory roles in cell signalling processes. This "redox regulation" appears to depend upon the reversible oxidation of cysteine residues within key proteins with reversible gluathionylation and formation of protein disulphides potentially leading to changes in the activities of proteins such as enzymes, transcription factors or transporters. Control of this process is dependent upon the local redox environment pertaining at a subcellular level. This short review provides examples of redox-regulated physiological processes in skeletal muscle that include some activation of transcription factors and changes in gene expression that result from contractile activity and the modulation of force generation during sustained contractions. There is also increasing evidence that dysregulation of redox-sensitive processes plays a role in the loss of muscle mass and function that occurs during normal ageing and in the gross muscle degeneration in disorders such as the muscular dystrophies. © 2008 IUBMB IUBMB Life, 60(8): 497,501, 2008 [source] Phospholipid signalling through phospholipase D and phosphatidic acidIUBMB LIFE, Issue 8 2006Rosanna Cazzolli Abstract Phospholipase D (PLD) hydrolyzes the phosphodiester bond of the predominant membrane phospholipid, phosphatidylcholine producing phosphatidic acid and free choline. This activity can participate in signal transduction pathways and impact on vesicle trafficking for secretion and endocytosis, as well as receptor signalling. Phospholipids can regulate PLD activity directly, through specific intermolecular interactions, or indirectly, through their effect on the localization or activity of PLD's protein effectors. This short review highlights these various phospholipid inputs into the regulation of PLD activity and also reviews potential roles for PLD-generated phosphatidic acid, particularly a mechanism by which the phospholipid may participate in the process of vesicular trafficking. iubmb Life, 58: 457 - 461, 2006 [source] Orthogonal Chemical Genetic Approaches for Unraveling Signaling PathwaysIUBMB LIFE, Issue 6 2005Kavita Shah Abstract While chemical genetic approach uses small molecules to probe protein functions in cells or organisms, orthogonal chemical genetics refers to strategies that utilize reengineered protein-small molecule interfaces, to alter specificities, in order to probe their functions. The advantage of orthogonal chemical genetics is that the changes at the interfaces are generally so minute that it goes undetected by natural processes, and thus depicts a true physiological picture of biological phenomenon. This review highlights the recent advances in the area of orthogonal chemical genetics, especially those designed to probe signaling processes. Dynamic protein-protein and enzyme-substrate interactions following stimuli form the foundation of signal transduction. These processes not only break spatial and temporal boundaries between interacting proteins, but also impart distinct regulatory properties by creating functional diversity at the interfaces. Functional and temporal modulation of these dynamic interactions by specific chemical probes provides extremely powerful tools to initiate, ablate, decouple and deconvolute different components of a signaling pathway at multiple stages. Not surprisingly, multiple receptor-ligand reengineering approaches have been developed in the last decade to selectively manipulate these transient interactions with the aim of unraveling signaling events. However, given the diversity of protein-protein interactions and novel chemical genetic probes developed to perturb these processes, a short review cannot do adequate justice to all aspects of signaling. For this reason, this review focuses on some orthogonal chemical-genetic strategies that are developed to study signaling processes involving enzyme-substrate interactions. IUBMB Life, 57: 397-405, 2005 [source] Innovation and transportation's technologiesJOURNAL OF ADVANCED TRANSPORTATION, Issue 1 2000Article first published online: 19 JAN 2010, William L. Garrison I critique the innovation processes that yield transportation's technologies, and to aid my analysis I look back to take advantage of the accumulation of experiences and insights marked by the millennium. I identify supply, transport, and user systems. Transport systems move things; supply systems provide fuel, pavements, and other inputs to transport activities; and user systems combine transport with other activities for socially useful purposes. The discussion then shifts from structure to behavior, and a short review of the emergence of today's systems reminds us that technological advances may improve the provision of old services, offer new ways of doing old things, or induce qualitative changes that enable doing new things. With these structural and behavioral matters in mind, I challenge the reader to judge the present situation and the future. [source] Sharks, skates and rays in the northeast Atlantic: population status, advice and managementJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2009M. W. Clarke Summary The fisheries management system in the northeast Atlantic is complicated. It was not designed with management or conservation of elasmobranchs in mind. Gradually, however, the system has taken elasmobranchs into account. Managers have asked science to provide advice, and in some cases management actions have followed. The purpose of this short review is to explain the system of assessment and advice, especially how it relates to sharks, skates and rays. Emphasis is on the legal framework, however, soft law and the role of the conservation movement are also discussed. [source] The Pacemaker Current: From Basics to the ClinicsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2007ANDREA BARBUTI Ph.D. Activation of the pacemaker ("funny," If) current during diastole is the main process underlying generation of the diastolic depolarization and spontaneous activity of cardiac pacemaker cells. If modulation by autonomic transmitters is responsible for the chronotropic regulation of heart rate. Given its role in pacemaking, If has been a major target of investigation aimed to exploit its rate-controlling function in a clinical perspective. In this short review, we describe some of the most recent clinically relevant applications of the concept of If -based pacemaking. [source] Prion diseases: contribution of high-resolution immunomorphologyJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 4 2001J-G. Fournier Abstract The transmisible spongiform encephalopathies or prion diseases are fatal neurological diseases that occur in animals and humans. They are characterized by the accumulation in the cerebral tissue of the abnormal form of prion protein (PrPsc) produced by a post-translational event involving conformational change of its normal cellular counterpart (PrPc). In this short review, we present some results on the biology of prion proteins which have benefited from morphological approaches combining the electron microscopy techniques and the immunodetection methods. We discuss data concerning in particular the physiological function of the normal cellular prion prion (PrPc) which have allowed to open up new vistas on prion diseases, the biogenesis of amyloid plaque and the cellular site involved in the prion protein conversion process. [source] The nature and reality of the aphid clone: genetic variation, adaptation and evolutionAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 2 2008Hugh D. Loxdale Abstract 1,When aphid clones and clonality are discussed, it is still often said that they are ,genetically identical', a statement for which there is no direct evidence, and certainly not for the entire genome. By contrast, there is a growing body of empirical data from the application of high resolution molecular (DNA) markers that aphid asexual lineages rapidly mutate and that, in some documented cases, this variation is selectable, either positively or negatively. 2,Although it is true that, in enclosed conditions (e.g. laboratory or field cage), a so-called clone as defined as the asexual progeny of a single foundress may be traceable, this is rarely if ever possible in the field without the use of genetic markers, and even then, usually only at a relatively few loci (multilocus genotypes, ,MLGs'). 3,The continued use of the term clone without qualification of its true nature and the reality of its interesting biology is likely to hamper a proper understanding of the ecology and evolution of these insects (which are interesting in their own right because of their complex life histories, but also because they are important as major pests globally, both by causing direct feeding damage and by transmitting pathogenic plant viruses and thereby leading to huge economic losses in the agricultural, horticultural and forestry industries). 4,In this short review, I provide evidence of what is now known about aphid clonality after the widespread use of molecular markers, comprising information mainly gained within the last 15 years or so. 5,The data demonstrate widespread adaptation and evolution, sometimes involving introgression and hybridization. Because of this new knowledge, our ideas of what constitutes a clone are in need of serious re-evaluation. [source] New strategies for polymer development in pharmaceutical science , a short reviewJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 9 2001A. Godwin We are developing synthetic polymers for pharmaceutical and medical applications. These applications can be broadly grouped on how the polymer will be utilized e.g. material, excipient or molecule. Our focus is to develop polymers with more defined structures that are based on biological, physicochemical and/or materials criteria. Strategies are being developed to more efficiently optimize structure,property correlations during preclinical development. We describe two examples of our research on pharmaceutical polymer development: narrow molecular weight distribution (MWD) homopolymeric precursors which can be functionalized to give families of narrow MWD homo- and co-polymers, and hydrolytically degradable polymers. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||