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Multiple Systems (multiple + system)

Distribution by Scientific Domains

Medical Sciences	28%
Life Sciences	21%

Terms modified by Multiple Systems

multiple system atrophy

Selected Abstracts

Xenopus axin-related protein: A link between its centrosomal localization and function in the Wnt/,-catenin pathway

DEVELOPMENTAL DYNAMICS, Issue 1 2010
Evguenia M. Alexandrova
Abstract The Wnt/,-catenin signaling pathway regulates cell proliferation and cell fate determination in multiple systems. However, the subcellular localization of Wnt pathway components and the significance of this localization for the pathway regulation have not been extensively analyzed. Here we report that Xenopus Axin-related protein (XARP), a component of the ,-catenin destruction complex, is localized to the centrosome. This localization of XARP requires the presence of the DIX domain and an adjacent region. Since other components of the Wnt pathway have also been shown to associate with the centrosome, we tested a hypothesis that the ,-catenin destruction complex operates at the centrosome. However, XARP mutants with poor centrosomal localization revealed an enhanced rather than decreased ability to antagonize the Wnt/,-catenin pathway. Our data are consistent with the idea that the inactivation of XARP at the centrosome is an important regulatory point in Wnt signaling. Developmental Dynamics 239:261,270, 2010. © 2009 Wiley-Liss, Inc. [source]

Assessment, intervention, and research with infants in out-of-home placement

INFANT MENTAL HEALTH JOURNAL, Issue 5 2002
Robert B. Clyman
Infants constitute a large and increasing proportion of youth in out-of-home placement. These infants have very high rates of medical illnesses, developmental delays, and substantial risks for psychopathology. They receive varying amounts of services from a complex and poorly integrated service system that includes four principal service sectors: the child welfare, medical, early intervention, and mental health service sectors. These service systems are currently undergoing major changes in their policies, organization, and financing, such as the introduction of managed care into the child welfare system. In this article, we provide an overview of what is known about infants in out-of-home placement. We then summarize approaches to infant mental health assessment and intervention from a comprehensive perspective that addresses the infants' multiple problems and acknowledges that they need to receive services from multiple systems that are undergoing rapid change. We conclude by highlighting a number of critical areas in need of research. ©2002 Michigan Association for Infant Mental Health. [source]

The characterization of the semi-solid W/O/W emulsions with low concentrations of the primary polymeric emulsifier

INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 2 2005
D. Vasiljevic
Synopsis Semi-solid multiple W/O/W emulsions with low concentrations (0.8, 1.6 and 2.4% w/w) of lipophilic polymeric primary emulsifier PEG-30-dipolyhydroxystearate (PDHS) have been formulated. Both emulsions, primary and multiple, were prepared with high content of inner phase (,1 = ,2 = 0.8). All the formulations differ only in the lipophilic emulsifier concentration. Evaluating several parameters such as macroscopic and microscopic aspect, droplet size, accelerated stability under centrifugation and flow and oscillatory rheological behaviour, assessed the multiple systems. It is possible to formulate the semi-solid W/O/W multiple emulsions with low concentrations of PDHS as the primary emulsifier. It appeared that the highest long-term stable multiple emulsion with the lowest droplet size, the highest apparent viscosity and highest elastic characteristic, was the sample with the highest concentration (2.4% w/w) of the primary emulsifier. Résumé Les émulsions H/L/H semi-solides ont été formulées avec les concentrations basses (0.8, 1.6 et 2.4% m/m) de l'émulsifiant lipophile polymèrique PEG-30-dipolyhydroxystearate. Les émulsions simples et multiples ont été préparées avec la teneur élevée en phase intérieure (,1 = ,2 = 0.8). La teneur en émulsifiant lipophile était la seule différence entre ces formulations. L'aspect macroscopique et microscopique, la taille de globules, la stabilité physique déterminée par le test de centrifugation ainsi que le comportement rhéologique (rhéologie d'écoulement et oscillatoire) ont permis l'évaluation des émulsions multiples. Il est possible de formuler les émulsions H/L/H semi-solides multiples avec les concentrations basses de PEG-30-dipolyhydroxystearate comme émulsifiant primaire. Il a été découvert que l'émulsion H/L/H multiple avec le plus grand pourcentage (2.4% m/m) de l'émulsifiant primaire a le diamètre de globule le plus petit, la plus grande viscosité apparente et le plus grand module élastique ainsi que la plus longue stabilité. [source]

Research Agenda for Frailty in Older Adults: Toward a Better Understanding of Physiology and Etiology: Summary from the American Geriatrics Society/National Institute on Aging Research Conference on Frailty in Older Adults

JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 6 2006
Jeremy Walston MD
Evolving definitions of frailty, and improved understanding of molecular and physiological declines in multiple systems that may increase vulnerability in frail, older adults has encouraged investigators from many disciplines to contribute to this emerging field of research. This article reports on the results of the 2004 American Geriatrics Society/National Institute on Aging conference on a Research Agenda on Frailty in Older Adults, which brought together a diverse group of clinical and basic scientists to encourage further investigation in this area. This conference was primarily focused on physical and physiological aspects of frailty. Although social and psychological aspects of frailty are critically important and merit future research, these topics were largely beyond the scope of this meeting. Included in this article are sections on the evolving conceptualization and definitions of frailty; physiological underpinnings of frailty, including the potential contributions of inflammatory, endocrine, skeletal muscle, and neurologic system changes; potential molecular and genetic contributors; proposed animal models; and integrative, system biology approaches that may help to facilitate future frailty research. In addition, several specific recommendations as to future directions were developed from suggestions put forth by participants, including recommendations on definition and phenotype development, methodological development to perform clinical studies of individual-system and multiple-system vulnerability to stressors, development of animal and cellular models, application of population-based studies to frailty research, and the development of large collaborative networks in which populations and resources can be shared. This meeting and subsequent article were not meant to be a comprehensive review of frailty research; instead, they were and are meant to provide a more-targeted research agenda-setting process. [source]

Chronic illness as a family process: A social-developmental approach to promoting resilience

JOURNAL OF CLINICAL PSYCHOLOGY, Issue 11 2002
Ester R. Shapiro
This paper describes a social-developmental approach to interventions in chronic illness using naturally occurring processes of change during family life-cycle transitions to promote more positive developmental outcomes. Clinical interventions can help build resilience by creating a therapeutic collaboration designed to help patients improve their use of existing and new resources in multiple systems. They can then better meet demands of the illness as it impacts on shared development. A case example of a 13-year-old daughter with complex, chronic health problems and developmental disabilities illustrates clinical interventions designed to promote family resilience during the entry into adolescence and a transition in schooling. This approach involves focusing on the family's own definition of the current problem and relevant history, constructing a multidimensional, coherent story of the illness and its impact that recognizes stressors yet highlights strengths, and normalizing their strategies for stability under circumstances of developmental stress. These interventions with mother, daughter, and family helped improve health efficacy, communication toward mutual understanding and shared problem solving, and better use of existing and new resources to enhance current and future developmental adaptation. © 2002 Wiley Periodicals, Inc. J Clin Psychol/In Session 58: 1375,1384, 2002. [source]

The King County (Washington) Systems Integration Initiative: A First Look at the Kent District Dual System Youth Pilot Program

JUVENILE AND FAMILY COURT JOURNAL, Issue 4 2009
Gene Siegel
ABSTRACT King County is one of five counties in Washington State participating in the John D. and Catherine T. MacArthur Foundation's Models for Change juvenile justice reform initiative. One key aspect of King County's Models for Change participation involves ongoing "systems integration" work intended to improve how youth who have cross-over involvement in multiple systems,e.g., juvenile justice, child welfare, education, mental health, and/or others,are handled. These cross-over cases often present a range of challenges to juvenile courts including substantial risk factors that increase their likelihood of continuing system involvement. This article provides a first look at an emerging pilot project in King County that is intended to improve how cross-over cases are handled by child welfare and juvenile probation with the longer term goal of improving outcomes for these difficult cases. [source]

Review article: recognition and treatment of eating disorders in primary and secondary care

ALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 4 2000
Robinson
Eating disorders are serious illnesses affecting 1,2% of young women. Patients may present to any doctor, sometimes atypically (e.g. unexplained weight loss, food allergy, infertility, diarrhoea), delaying diagnosis and leading to needless investigation. The cardinal signs are weight loss, amenorrhoea, bingeing with vomiting and other compensatory behaviours, and disturbances in body image with an exaggeration of the importance of slimness. When other causes have been excluded, useful investigations are serum potassium, bone mineral density scanning and pelvic ultrasound. In emaciated patients multiple systems may fail with pancytopaenia, neuromyopathy and heart failure. Clinical assessment of muscle power is used to monitor physical risk. Treatment may involve individual, group or family sessions, using cognitive-behavioural, psychodynamic and family approaches. More severe or intractable illness is treated with day care, with in-patient care in a medical or specialist psychiatric unit reserved for the most severely ill patients. Antidepressants have a place in the treatment of bulimia nervosa unresponsive to psychological approaches, and when severe depressive symptoms develop. The children of people with eating disorders may have an increased risk of difficulties. Support for the patient and family, and effective liaison between professionals, are essential in the treatment of severe eating disorders. [source]

Revealing the hidden complexities of mtDNA inheritance

MOLECULAR ECOLOGY, Issue 23 2008
DANIEL JAMES WHITE
Abstract Mitochondrial DNA (mtDNA) is a pivotal tool in molecular ecology, evolutionary and population genetics. The power of mtDNA analyses derives from a relatively high mutation rate and the apparent simplicity of mitochondrial inheritance (maternal, without recombination), which has simplified modelling population history compared to the analysis of nuclear DNA. However, in biology things are seldom simple, and advances in DNA sequencing and polymorphism detection technology have documented a growing list of exceptions to the central tenets of mitochondrial inheritance, with paternal leakage, heteroplasmy and recombination now all documented in multiple systems. The presence of paternal leakage, recombination and heteroplasmy can have substantial impact on analyses based on mtDNA, affecting phylogenetic and population genetic analyses, estimates of the coalescent and the myriad of other parameters that are dependent on such estimates. Here, we review our understanding of mtDNA inheritance, discuss how recent findings mean that established ideas may need to be re-evaluated, and we assess the implications of these new-found complications for molecular ecologists who have relied for decades on the assumption of a simpler mode of inheritance. We show how it is possible to account for recombination and heteroplasmy in evolutionary and population analyses, but that accurate estimates of the frequencies of biparental inheritance and recombination are needed. We also suggest how nonclonal inheritance of mtDNA could be exploited, to increase the ways in which mtDNA can be used in analyses. [source]

Protostellar discs formed from rigidly rotating cores

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2009
S. Walch
ABSTRACT We use three-dimensional smoothed particle hydrodynamic simulations to investigate the collapse of low-mass pre-stellar cores and the formation and early evolution of protostellar discs. The initial conditions are slightly supercritical Bonnor,Ebert spheres in rigid rotation. The core mass and initial radius are held fixed at MO= 6.1 M, and RO= 17 000 au, and the only parameter that we vary is the initial angular speed ,O. Protostellar discs forming from cores with ,O < 1.35 × 10,13 s,1 have radii between 100 and 300 au and are quite centrally concentrated; due to heating by gas infall on to the disc and accretion on to the central object, they are also quite warm, , and therefore stable against gravitational fragmentation. In contrast, more rapidly rotating cores form discs which are less concentrated and cooler, and have radii between 400 and 1000 au; as a consequence they are prone to gravitational fragmentation and the formation of multiple systems. We derive a criterion that predicts whether a rigidly rotating core having given MO, RO and ,O will produce a protostellar disc which fragments whilst material is still infalling from the core envelope. We then apply this criterion to core samples for which MO, RO and ,O have been estimated observationally. We conclude that the observed cores are stable against fragmentation at this stage, due to their low angular speeds and the heat delivered at the accretion shock where the infalling material hits the disc. [source]

Star cluster ecology , V. Dissection of an open star cluster: spectroscopy

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2004
Simon F. Portegies Zwart
ABSTRACT We have modelled in detail the evolution of rich open star clusters such as NGC 2516, NGC 2287, Pleiades, Praesepe, Hyades, NGC 2660 and 3680, using simulations that include stellar dynamics as well as the effects of stellar evolution. The dynamics is modelled via direct N -body integration, while the evolution of single stars and binaries is followed through the use of fitting formulae and recipes. The feedback of stellar and binary evolution on the dynamical evolution of the stellar system is taken into account self-consistently. Our model clusters dissolve in the tidal field of the Galaxy in a time-span of the order of a billion years. The rate of mass loss is rather constant, ,1 M, per million years. The binary fraction at first is nearly constant in time, then increases slowly near the end of a cluster's lifetime. For clusters which are more than about 108 yr old the fractions of stars in the form of binaries, giants and merger products in the inner few core radii are considerably higher than in the outer regions, beyond the cluster's half-mass radius. When stars with masses ,2 M, escape from the cluster, they tend to do so with velocities higher than average. The stellar merger rate in our models is roughly one per 30 million years. Most mergers are the result of unstable mass transfer in close binaries (,70 per cent), but a significant minority are caused by direct encounters between single and binary stars. While most mergers occur within the cluster core, even beyond the half-mass radius stellar mergers occasionally take place. We notice a significant birth rate of X-ray binaries, most containing a white dwarf as the mass acceptor. We also find one high-mass X-ray binary with a neutron-star accretor. If formed and retained, black holes participate in many (higher-order) encounters in the cluster centre, resulting in a large variety of exotic binaries. The persistent triple and higher-order systems formed in our models by dynamical encounters between binaries and single stars are not representative for the multiple systems observed in the Galactic disc. We conclude that the majority of multiples in the disc probably formed when the stars were born, rather than through later dynamical interactions. [source]

On the properties of young multiple stars

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2004
E. J. Delgado-Donate
ABSTRACT We present numerical results on the properties of young binary and multiple stellar systems. Our analysis is based on a series of smoothed particle hydrodynamics (SPH) +N -body simulations of the fragmentation of small molecular clouds, which fully resolve the opacity limit for fragmentation. These simulations demonstrate that multiple star formation is a major channel for star formation in turbulent flows. We have produced a statistically significant number of stable multiple systems, with component separations in the range ,1,103 au. At the end of the hydrodynamic stage (0.5 Myr), we find that ,60 per cent of stars and brown dwarfs are members of multiples systems, with about a third of these being low-mass, weakly bound outliers in wide eccentric orbits. Our results imply that in the stellar regime most stars are in multiples (,80 per cent) and that this fraction is an increasing function of primary mass. After N -body integration to 10.5 Myr, the percentage of bound objects has dropped to about 40 per cent, this decrease arising mostly from very low-mass stars and brown dwarfs that have been released into the field. Brown dwarfs are never found to be very close companions to stars (the brown dwarf desert at very small separations), but one case exists of a brown dwarf companion at intermediate separations (10 au). Our simulations can accommodate the existence of brown dwarf companions at large separations, but only if the primaries of these systems are themselves multiples. We have compared the outcome of our simulations with the properties of real stellar systems as deduced from the infrared colour,magnitude diagram of the Praesepe cluster and from spectroscopic and high-resolution imaging surveys of young clusters and the field. We find that the spread of the observed main sequence of Praesepe in the 0.4,1 M, range appears to require that stars are indeed commonly assembled into high-order multiple systems. Similarly, observational results from Taurus and , Ophiuchus, or moving groups such as TW Hydrae and MBM 12, suggest that companion frequencies in young systems can indeed be as high as we predict. The comparison with observational data also illustrates two problems with the simulation results. First, low mass ratio (q < 0.2) binaries are not produced by our models, in conflict with both the Praesepe colour,magnitude diagram and independent evidence from field binary surveys. Secondly, very low-mass stars and brown dwarf binaries appear to be considerably underproduced by our simulations. [source]

The role of Gab family scaffolding adapter proteins in the signal transduction of cytokine and growth factor receptors

CANCER SCIENCE, Issue 12 2003
Keigo Nishida
The Grb2-associated binder (Gab) family adapter proteins are scaffolding adapter molecules that display sequence similarity with Drosophila DOS (daughter of sevenless), which is a substrate for the protein tyrosine phosphatase Corkscrew. Gab proteins contain a pleckstrin homology (PH) domain and binding sites for SH2 and SH3 domains. A number of studies in multiple systems have implicated Gab in signaling via many different types of receptors, such as growth factor, cytokine, and antigen receptors, and via oncoproteins. Recent studies of Gab1 and Gab2 knockout mice have clearly indicated an important role for Gabs in vivo. Gab1-deficient mice die as embryos with multiple defects in placental, heart, skin, and muscle development. Gab2-deficient mice are viable, but have a defect in the mast cell lineages and in allergic reactions. Given the apparently central role played by Gab signaling via many receptors, delineating the precise mechanism(s) of Gab-mediated signaling is critical to understanding how cytokines, growth factors, and oncoproteins mediate a variety of biological activities: cell growth, differentiation, survival and malignant transformation. [source]

Of old and new diseases: genetics of pituitary ACTH excess (Cushing) and deficiency

CLINICAL GENETICS, Issue 3 2007
J Drouin
The pituitary gland orchestrates our endocrine environment: it produces hormones in response to hypothalamic factors that integrate neural inputs and its activity is balanced by the feedback action of peripheral hormones. Disruption of this equilibrium has severe consequences that affect multiple systems and may be fatal. Genetic analysis of pituitary function led to discovery of critical transcription factors that cause hormone deficiencies when mis-expressed. This review will summarize recent findings that led to the first complete clinical description of inherited, isolated corticotropin (ACTH) deficiency (IAD) and to the first molecular mechanism for excessive ACTH production in Cushing's disease. Indeed, mutations in TPIT, a positive or negative regulator of cell fates for different pituitary lineages, cause neonatal IAD, a condition considered anecdotic before discovery of this transcription factor. Cushing's disease is caused by corticotroph adenomas that produce excess ACTH as a result of resistance to glucocorticoids (Gc). Molecular investigation of the normal mechanism of Gc feedback led to identification of two essential proteins for pro-opiomelanocortin repression that are often mis-expressed in corticotroph adenomas thus providing a molecular explanation for Gc resistance. These two proteins, Brg1 and histone deacetylase 2 (HDAC2), are involved in chromatin remodeling and may also participate in the tumorigenic process, as Brg1 is a tumor suppressor. These recent advances have provided improved diagnosis and opened new perspectives for patient management and therapies. [source]