Human Systems (human + system)

Distribution by Scientific Domains


Selected Abstracts


Leukocyte extravasation as a target for anti-inflammatory therapy , Which molecule to choose?

EXPERIMENTAL DERMATOLOGY, Issue 1 2005
W.-H. Boehncke
Despite some disappointments during the clinical use of these agents and despite their crippling price tag, the recent incorporation of biologicals that target defined molecular controls of leukocyte extravasation into dermatological and rheumatological practise, consequently, has greatly enriched our therapeutic options for battling major, chronic, inflammatory dermatoses such as psoriasis. However, the , as yet unresolved and still rather controversially discussed , critical question is: Which of the multiple steps that control leukocyte extravasation in the human system really offer the most promising, most pragmatic, and safest molecular targets for therapeutic intervention for which disease entity? The current debate intends to stimulate public and rational debate of this crucial issue, beyond the evident commercial interests that are touched by whatever stand one takes. [source]


Effect of the small molecule plasminogen activator inhibitor-1 (PAI-1) inhibitor, PAI-749, in clinical models of fibrinolysis

JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 6 2010
A. J. LUCKING
Summary.,Background:,The principal inhibitor of fibrinolysis in vivo is plasminogen activator inhibitor-1 (PAI-1). PAI-749 is a small molecule inhibitor of PAI-1 with proven antithrombotic efficacy in several preclinical models. Objective:,To assess the effect of PAI-749, by using an established ex vivo clinical model of thrombosis and a range of complementary in vitro human plasma-based and whole blood-based models of fibrinolysis. Methods:,In a double-blind, randomized, crossover study, ex vivo thrombus formation was assessed using the Badimon chamber in 12 healthy volunteers during extracorporeal administration of tissue-type plasminogen activator (t-PA) in the presence of PAI-749 or control. t-PA-mediated lysis of plasma clots and of whole blood model thrombi were assessed in vitro. The role of vitronectin was examined by assessing lysis of fibrin clots generated from purified plasma proteins. Results:,There was a dose-dependent reduction in ex vivo thrombus formation by t-PA (P < 0.0001). PAI-749 had no effect on in vitro or ex vivo thrombus formation or fibrinolysis in the presence or absence of t-PA. Inhibition of PAI-1 with a blocking antibody enhanced fibrinolysis in vitro (P < 0.05). Conclusions: Despite its efficacy in a purified human system and in preclinical models of thrombosis, the current study suggests that PAI-749 does not affect thrombus formation or fibrinolysis in a range of established human plasma and whole blood-based systems. [source]


Occupational science: a renaissance of service to humankind through knowledge

OCCUPATIONAL THERAPY INTERNATIONAL, Issue 2 2000
Elizabeth J. Yerxa EdD, FAOTA, LHD (Hon) ScD (Hon) OTR
Abstract The context for the development of occupational science, the study of the human as an occupational being, included the worldwide increase in the population of people with chronic impairments, decreased resources for people with handicaps, growth in the complexity of daily life and the global maturation of the profession of occupational therapy. Occupational science promises that occupational therapists will define the knowledge base of the profession and its appropriate scope of practice through scholarly work. Occupational scientists need to develop a fresh synthesis of ideas from those scholarly disciplines that view the human as a complex being who interacts with the environment by using occupation over the three time spans of evolution, human development and learning; occupation as agency; and viewing the person served as Homo occupacio, a dynamic, open human system. The occupational human engages in daily life through development of a repertoire of skills which adheres to the rules of culture. Such study will need to include the contexts in which people carry out their rounds of occupation. The ,detective work' of occupational scientists, contributing to but not bound by the immediate demands of occupational therapy practice, will be guided by the values and traditions of the field to ensure its relevance and ethical foundation. The most important tool of the world community of occupational therapists will be the mind of the occupational therapist, who, through knowledge of occupation, will foster human capability and influence health. Copyright © 2000 Whurr Publishers Ltd. [source]


The Heart of the Matter: An Essay about the Effects of Managed Care on Family Therapy with Children,

FAMILY PROCESS, Issue 4 2001
Ellen Pulleyblank Coffey Ph.d.
This essay is based on a pilot study that examined the effects of managed care on the treatment of children and families, with special attention to community mental health. We embarked on the pilot study to test the accuracy and generalizability of our impression that family therapy and other systemic practices have been marginalized in ordinary clinics and agencies, and to understand the reasons why. We interviewed managed care providers, researchers, family therapy trainers, and clinicians in the Northeast. Our findings led to seven themes that support our impression that, even though there is a consensus about the need for coordinated family-based services, there is a disconnection between state policies, contractual requirements and what is actually occurring at the implementation level. This study suggests that our knowledge of human systems may be in danger of being disqualified and lost, with damaging consequences for the care of children. Yet, as systemic thinkers and practitioners, it is our belief that ethical and effective treatment need not be at odds with care that is cost-efficient. The direction of our future research will be to study whether the involvement of all stakeholders at all levels of planning and training leads to systemic family-based practices that consistently save costs and provide high-quality care. [source]


Host culling as an adaptive management tool for chronic wasting disease in white-tailed deer: a modelling study

JOURNAL OF APPLIED ECOLOGY, Issue 2 2009
Gideon Wasserberg
Summary 1Emerging wildlife diseases pose a significant threat to natural and human systems. Because of real or perceived risks of delayed actions, disease management strategies such as culling are often implemented before thorough scientific knowledge of disease dynamics is available. Adaptive management is a valuable approach in addressing the uncertainty and complexity associated with wildlife disease problems and can be facilitated by using a formal model. 2We developed a multi-state computer simulation model using age, sex, infection-stage, and seasonality as a tool for scientific learning and managing chronic wasting disease (CWD) in white-tailed deer Odocoileus virginianus. Our matrix model used disease transmission parameters based on data collected through disease management activities. We used this model to evaluate management issues on density- (DD) and frequency-dependent (FD) transmission, time since disease introduction, and deer culling on the demographics, epizootiology, and management of CWD. 3Both DD and FD models fit the Wisconsin data for a harvested white-tailed deer population, but FD was slightly better. Time since disease introduction was estimated as 36 (95% CI, 24,50) and 188 (41,>200) years for DD and FD transmission, respectively. Deer harvest using intermediate to high non-selective rates can be used to reduce uncertainty between DD and FD transmission and improve our prediction of long-term epidemic patterns and host population impacts. A higher harvest rate allows earlier detection of these differences, but substantially reduces deer abundance. 4Results showed that CWD has spread slowly within Wisconsin deer populations, and therefore, epidemics and disease management are expected to last for decades. Non-hunted deer populations can develop and sustain a high level of infection, generating a substantial risk of disease spread. In contrast, CWD prevalence remains lower in hunted deer populations, but at a higher prevalence the disease competes with recreational hunting to reduce deer abundance. 5Synthesis and applications. Uncertainty about density- or frequency-dependent transmission hinders predictions about the long-term impacts of chronic wasting disease on cervid populations and the development of appropriate management strategies. An adaptive management strategy using computer modelling coupled with experimental management and monitoring can be used to test model predictions, identify the likely mode of disease transmission, and evaluate the risks of alternative management responses. [source]


PACIFIC NORTHWEST REGIONAL ASSESSMIENT: THE IMPACTS OF CLIMATE VARIABILITY AND CLIMATE CHANGE ON THE WATER RESOURCES OF TEE COLUMBIA RWER BASIN,

JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 2 2000
Edward L. Miles
ABSTRACT: The Pacific Northwest (PNW) regional assessment is an integrated examination of the consequences of natural climate variability and projected future climate change for the natural and human systems of the region. The assessment currently focuses on four sectors: hydrology/water resources, forests and forestry, aquatic ecosystems, and coastal activities. The assessment begins by identifying and elucidating the natural patterns of climate vanability in the PNW on interannual to decadal timescales. The pathways through which these climate variations are manifested and the resultant impacts on the natural and human systems of the region are investigated. Knowledge of these pathways allows an analysis of the potential impacts of future climate change, as defined by IPCC climate change scenarios. In this paper, we examine the sensitivity, adaptability and vulnerability of hydrology and water resources to climate variability and change. We focus on the Columbia River Basin, which covers approximately 75 percent of the PNW and is the basis for the dominant water resources system of the PNW. The water resources system of the Columbia River is sensitive to climate variability, especially with respect to drought. Management inertia and the lack of a centralized authority coordinating all uses of the resource impede adaptability to drought and optimization of water distribution. Climate change projections suggest exacerbated conditions of conflict between users as a result of low summertime streamfiow conditions. An understanding of the patterns and consequences of regional climate variability is crucial to developing an adequate response to future changes in climate. [source]


Towards an integrated environmental assessment for wetland and catchment management

THE GEOGRAPHICAL JOURNAL, Issue 2 2003
R Kerry Turner
This paper develops a decision support system for evaluation of wetland ecosystem management strategy and examines its, so far partial, application in a case study of an important complex coastal wetland known as the Norfolk and Suffolk Broads, in the east of England, UK. Most managed ecosystems are complex and often poorly understood hierarchically organized systems. Capturing the range of relevant impacts on natural and human systems under different management options will be a formidable challenge. Biodiversity has a hierarchical structure which ranges from the ecosystem and landscape level, through the community level and down to the population and genetic level. There is a need to develop methodologies for the practicable detection of ecosystem change, as well as the evaluation of different ecological functions. What is also required is a set of indicators (environmental, social and economic) which facilitate the detection of change in ecosystems suffering stress and shock and highlight possible drivers of the change process. A hierarchical classification of ecological indicators of sustainability would need to take into account existing interactions between different organization levels, from species to ecosystems. Effects of environmental stress are expressed in different ways at different levels of biological organization and effects at one level can be expected to impact other levels, often in unpredictable ways. The management strategy, evaluation methodologies and indicators adopted should also assess on sustainability grounds whether any given management option is supporting, or reducing, the diversity of functions which are providing stakeholders with the welfare benefits they require. [source]


Practical theory, practical art, and the pragmatic-systemic account of inquiry

COMMUNICATION THEORY, Issue 1 2001
Vernon E. Cronen
Practical theory, as distinct from applied theory, is based on the notion of inquiry developed in human systems research and pragmatism. It rejects the practitioner-theorist dualism and treats theory as formalizations aiding inquirers' efforts to join with human systems to improve them, rather than as propositional maps of social reality. This article offers criteria for evaluating such theories and discusses the way practical theory establishes reliability, validity, and generality. [source]