77 research outputs found
Innate Immune Deficiency of Extremely Premature Neonates Can Be Reversed by Interferon-γ
Background: Bacterial sepsis is a major threat in neonates born prematurely, and is associated with elevated morbidity and mortality. Little is known on the innate immune response to bacteria among extremely premature infants. Methodology/Principal Findings: We compared innate immune functions to bacteria commonly causing sepsis in 21 infants of less than 28 wks of gestational age, 24 infants born between 28 and 32 wks of gestational age, 25 term newborns and 20 healthy adults. Levels of surface expression of innate immune receptors (CD14, TLR2, TLR4, and MD-2) for Grampositive and Gram-negative bacteria were measured in cord blood leukocytes at the time of birth. The cytokine response to bacteria of those leukocytes as well as plasma-dependent opsonophagocytosis of bacteria by target leukocytes was also measured in the presence or absence of interferon-c. Leukocytes from extremely premature infants expressed very low levels of receptors important for bacterial recognition. Leukocyte inflammatory responses to bacteria and opsonophagocytic activity of plasma from premature infants were also severely impaired compared to term newborns or adults. These innate immune defects could be corrected when blood from premature infants was incubated ex vivo 12 hrs with interferon-c. Conclusion/Significance: Premature infants display markedly impaired innate immune functions, which likely account for their propensity to develop bacterial sepsis during the neonatal period. The fetal innate immune response progressivel
Advances in rheumatology: new targeted therapeutics
Treatment of inflammatory arthritides - including rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis - has seen much progress in recent years, partially due to increased understanding of the pathogenesis of these diseases at the cellular and molecular levels. These conditions share some common mechanisms. Biologic therapies have provided a clear advance in the treatment of rheumatological conditions. Currently available TNF-targeting biologic agents that are licensed for at east one of the above-named diseases are etanercept, infliximab, adalimumab, golimumab, and certolizumab. Biologic agents with a different mechanism of action have also been approved in rheumatoid arthritis (rituximab, abatacept, and tocilizumab). Although these biologic agents are highly effective, there is a need for improved management strategies. There is also a need for education of family physicians and other healthcare professionals in the identification of early symptoms of inflammatory arthritides and the importance of early referral to rheumatologists for diagnosis and treatment. Also, researchers are developing molecules - for example, the Janus kinase inhibitor CP-690550 (tofacitinib) and the spleen tyrosine kinase inhibitor R788 (fostamatinib) - to target other aspects of the inflammatory cascade. Initial trial results with new agents are promising, and, in time, head-to-head trials will establish the best treatment options for patients. The key challenge is identifying how best to integrate these new, advanced therapies into daily practice
Deterministic Chaos and Fractal Complexity in the Dynamics of Cardiovascular Behavior: Perspectives on a New Frontier
Physiological systems such as the cardiovascular system are capable of five kinds of behavior: equilibrium, periodicity, quasi-periodicity, deterministic chaos and random behavior. Systems adopt one or more these behaviors depending on the function they have evolved to perform. The emerging mathematical concepts of fractal mathematics and chaos theory are extending our ability to study physiological behavior. Fractal geometry is observed in the physical structure of pathways, networks and macroscopic structures such the vasculature and the His-Purkinje network of the heart. Fractal structure is also observed in processes in time, such as heart rate variability. Chaos theory describes the underlying dynamics of the system, and chaotic behavior is also observed at many levels, from effector molecules in the cell to heart function and blood pressure. This review discusses the role of fractal structure and chaos in the cardiovascular system at the level of the heart and blood vessels, and at the cellular level. Key functional consequences of these phenomena are highlighted, and a perspective provided on the possible evolutionary origins of chaotic behavior and fractal structure. The discussion is non-mathematical with an emphasis on the key underlying concepts
Predicting adverse drug reactions in older adults; a systematic review of the risk prediction models
Jennifer M Stevenson,1,2 Josceline L Williams,1,2 Thomas G Burnham,2 A Toby Prevost,3 Rebekah Schiff,4 S David Erskine,2 J Graham Davies1 1Institute of Pharmaceutical Sciences, King’s College London, London, UK; 2Pharmacy Department, St Thomas’ Hospital, Guy’s and St Thomas’ NHS Foundation Trust, London, UK; 3Department of Primary Care and Public Health Sciences, King’s College London, London, UK; 4Department of Ageing and Health, Guy’s and St Thomas’ NHS Foundation Trust, London, UK Abstract: Adverse drug reaction (ADR) risk-prediction models for use in older adults have been developed, but it is not clear if they are suitable for use in clinical practice. This systematic review aimed to identify and investigate the quality of validated ADR risk-prediction models for use in older adults. Standard computerized databases, the gray literature, bibliographies, and citations were searched (2012) to identify relevant peer-reviewed studies. Studies that developed and validated an ADR prediction model for use in patients over 65 years old, using a multivariable approach in the design and analysis, were included. Data were extracted and their quality assessed by independent reviewers using a standard approach. Of the 13,423 titles identified, only 549 were associated with adverse outcomes of medicines use. Four met the inclusion criteria. All were conducted in inpatient cohorts in Western Europe. None of the models satisfied the four key stages in the creation of a quality risk prediction model; development and validation were completed, but impact and implementation were not assessed. Model performance was modest; area under the receiver operator curve ranged from 0.623 to 0.73. Study quality was difficult to assess due to poor reporting, but inappropriate methods were apparent. Further work needs to be conducted concerning the existing models to enable the development of a robust ADR risk-prediction model that is externally validated, with practical design and good performance. Only then can implementation and impact be assessed with the aim of generating a model of high enough quality to be considered for use in clinical care to prioritize older people at high risk of suffering an ADR. Keyword: aged, stratified care, prognosis, medication-related har
Predicting adverse drug reactions in older adults; a systematic review of the risk prediction models
Adverse drug reaction (ADR) risk-prediction models for use in older adults have been developed, but it is not clear if they are suitable for use in clinical practice. This systematic review aimed to identify and investigate the quality of validated ADR risk-prediction models for use in older adults. Standard computerized databases, the gray literature, bibliographies, and citations were searched (2012) to identify relevant peer-reviewed studies. Studies that developed and validated an ADR prediction model for use in patients over 65 years old, using a multivariable approach in the design and analysis, were included. Data were extracted and their quality assessed by independent reviewers using a standard approach. Of the 13,423 titles identified, only 549 were associated with adverse outcomes of medicines use. Four met the inclusion criteria. All were conducted in inpatient cohorts in Western Europe. None of the models satisfied the four key stages in the creation of a quality risk prediction model; development and validation were completed, but impact and implementation were not assessed. Model performance was modest; area under the receiver operator curve ranged from 0.623 to 0.73. Study quality was difficult to assess due to poor reporting, but inappropriate methods were apparent. Further work needs to be conducted concerning the existing models to enable the development of a robust ADR risk-prediction model that is externally validated, with practical design and good performance. Only then can implementation and impact be assessed with the aim of generating a model of high enough quality to be considered for use in clinical care to prioritize older people at high risk of suffering an ADR
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