Neuromuscular Blockade with Rocuronium Bromide Increases the Tolerance of Acute Normovolemic Anemia in Anesthetized Pigs

Background: The patient's individual anemia tolerance is pivotal when blood transfusions become necessary, but are not feasible for some reason. To date, the effects of neuromuscular blockade (NMB) on anemia tolerance have not been investigated. Methods: 14 anesthetized and mechanically ventilated pigs were randomly assigned to the Roc group (3.78 mg/kg rocuronium bromide followed by continuous infusion of 1 mg/kg/min, n = 7) or to the Sal group (administration of the corresponding volume of normal saline, n = 7). Subsequently, acute normovolemic anemia was induced by simultaneous exchange of whole blood for a 6% hydroxyethyl starch solution (130/0.4) until a sudden decrease of total body O-2 consumption (VO2) indicated a critical limitation of O-2 transport capacity. The Hb concentration quantified at this time point (Hb(crit)) was the primary end-point of the protocol. Secondary endpoints were parameters of hemodynamics, O-2 transport and tissue oxygenation. Results: Hb(crit) was significantly lower in the Roc group (2.4 +/- 0.5 vs. 3.2 +/- 0.7 g/dl) reflecting increased anemia tolerance. NMB with rocuronium bromide reduced skeletal muscular VO2 and total body O-2 extraction rate. As the cardiac index increased simultaneously, total body VO2 only decreased marginally in the Roc group (change of VO2 relative to baseline -1.7 +/- 0.8 vs. 3.2 +/- 1.9% in the Sal group, p < 0.05). Conclusion: Deep NMB with rocuronium bromide increases the tolerance of acute normovolemic anemia. The underlying mechanism most likely involves a reduction of skeletal muscular VO2. During acellular treatment of an acute blood loss, NMB might play an adjuvant role in situations where profound stages of normovolemic anemia have to be tolerated (e.g. bridging an unexpected blood loss until blood products become available for transfusion). Copyright (C) 2011 S. Karger AG, Base

Macular pigment and percentage of body fat

PURPOSE. To investigate the relationship between percentage of body fat and macular pigment (MP) optical density. METHODS. One hundred healthy subjects of ages between 22 and 60 years volunteered to participate in this study. MP optical density was measured psychophysically, serum lutein and zeaxanthin were quantified by HPLC, and dietary intake of lutein and zeaxanthin was assessed using a validated food frequency questionnaire. Body fat was measured by dual energy x-ray absorptiometry (DEXA); body mass index (BMI) was also calculated for each subject. Clinical and personal details were recorded, with particular attention directed toward putative risk factors for AMD. RESULTS. There was a significant inverse relationship between the percentage of body fat and MP optical density in males (r ϭ Ϫ0.392, P Ͻ 0.01), and after correcting for age and dietary lutein and zeaxanthin, this inverse relationship remained significant (r ϭ Ϫ0.290, P Ͻ 0.05). The relationship between MP optical density and percentage of body fat in females was inverse, but not significant (r ϭ Ϫ0.197, P ϭ 0.149). A significant and inverse relationship between serum zeaxanthin and percentage of body fat was observed for females only (r ϭ Ϫ0.354, P Ͻ 0.01). Dietary intake of fat was inversely related to serum lutein and zeaxanthin, and significantly so for lutein (r ϭ Ϫ0.256, P Ͻ 0.05). However, dietary fat was unrelated to MP optical density (r ϭ 0.041, P ϭ 0.688). CONCLUSIONS. A relative lack of MP is associated with adiposity in men, and may underlie the association between body fat and risk for AMD progression in males. Further, the processes governing accumulation and/or stabilization of lutein and zeaxanthin in fat tissue appear to differ for males and females. (Invest Ophthalmol Vis Sci. 2004;45:3940 -3950) DOI: 10.1167/iovs.04-0273 A ge-related macular degeneration (AMD), which damages central vision, is the late stage of age-related maculopathy (ARM), and is the leading cause of blindness in elderly people in the Western World. 1 Under physiological conditions, lutein and zeaxanthin accumulate at the macula to the exclusion of all other carotenoids, and are collectively known as macular pigment (MP). The function of MP remains uncertain, but it is believed to reduce chromatic aberration as a result of its absorption spectrum which peaks at 460 nm (blue light). 2 These absorptive characteristics, alone or in combination with the capacity of the retinal carotenoids to quench reactive oxygen intermediates (ROIs), allow the MP to protect the retina from oxidative damage. Although the pathogenesis of AMD remains unclear, there is a growing body of evidence implicating oxidative stress, which refers to tissue damage arising from interaction between the constituent molecules of a tissue and ROIs. The retina is an ideal site for the generation of ROIs because of its high oxygen consumption, its wealth of chromophores, and its exposure to short wavelength visible light. Body fat is of particular interest, because adipose tissue is a major storage organ for carotenoids. 8 Of note, several large population-based studies have found an association between incidence and/or prevalence of AMD and BMI. 9 -13 BMI lends itself as a measure of obesity in epidemiologic studies, largely because it is quick and easy to record. However, the accuracy of BMI (a simple weight to height ratio) as a measure of fat mass, and consequently as a tool for investigating its relationship with carotenoid levels in the blood and retina, remains controversial. -17 The present study was designed to investigate the relationship between MP optical density and percentage of body fat as measured by dual energy x-ray absorptiometry (DEXA), which is the most available direct assessment of fat mass. The relationship between adiposity and serum concentrations of lutein and zeaxanthin was also evaluated. METHODS Subjects One hundred healthy subjects volunteered to participate in this study, which was approved by the Research Ethics Committee of Waterford Regional Hospital and the Ethics Committee of the Waterford Institute of Technology. Informed consent was obtained from each volunteer, and the experimental procedures adhered to the tenets of the Declaration of Helsinki. Subjects were recruited to this single-visit study at the Waterford Institute of Technology by a self-selected sample population who volunteered as a result of posters, newsletters, and word of mouth in the local community. Subjects had to be white between the ages of 20 and 60 years. Volunteers with ocular pathology were excluded. The following details were recorded for each volunteer: demographic data; general health status, with particular attention directed From th

Exercise and Hospitalized Leukemia Patients

Objective: The purpose of this study was to determine if patients in a structured, monitored walking program experienced less symptom distress than patients receiving the usual standard of care during induction chemotherapy

Exploring children’s perspectives on the welfare needs of pet animals

This work was supported by the Department for Environment, Food and Rural Affairs (grant number AW1404).Children are increasingly viewed as important recipients of eduational interventions to improve animal welfare, yet research examining their perspectives is lacking, particularly within the UK. Helping children to care appropriately for animals depends, not least, on an ability to understand the needs of different species and correctly identify cues given by the animal that indicate its welfare state. This study began to explore: (a) children’s perceptions of welfare needs, focusing on four common pet animals; (b) influences on the development of knowledge; (c) beliefs about whether or not (all) animals are sentient, and (d) their confidence in identifying when their own pets are in need. Fourteen focus groups were carried out with 53 children aged 7 to 13 years. Findings highlighted an affirmative response that animals have feelings (dogs especially), albeit with doubts about this applying universally. There was wide variation in children’s knowledge of welfare needs, even among owners of the animal in question. Conversely, some children lacked confidence in spite of the extensive knowledge they had developed through direct experience. An important finding was a perceived difficulty in identifying the needs of particular species or specific types of need in their own pets. Fitting well with a recent emphasis on “positive welfare,” children felt that many animals need demonstrative love and attention, especially cats and dogs. While there is clearly scope for educating children about common needs and cues that indicate animals’ welfare state, other areas pose a greater challenge. Emotional connection seems important in the development of extensive knowledge and concern for welfare. Accordingly, animals that do not possess the kind of behavioral repertoire that is easy to interpret or allows for a perceived sense of reciprocity are possibly at risk of negative welfare experiences.PostprintPeer reviewe

Controversial role of plant sterol esters in the management of hypercholesterolaemia

Hypercholesterolaemia is a risk factor of cardiovascular diseases and is therefore a major target for primary and secondary prevention. Maintaining a healthy diet and lifestyle reduces cardiovascular risk. 'Functional foods'; supplemented with phytosterols are advertised for the management of hypercholesterolaemia and have become a widely used non-prescription approach to lower plasma cholesterol levels. It is estimated that in 2005 worldwide 3 billion US-dollars were spent on various functional foods that have regulator-approved health claims for the management of elevated cholesterol levels. In September 2000, the US Food and Drug Administration (FDA) issued an interim final rule allowing a health claim for reducing the risk of coronary heart disease for foods that contain phytosterols and are low in saturated fat and cholesterol. In fact, this was only the 12th time the FDA has authorized a health claim. The National Cholesterol Education Program Expert Panel (NCEP ATP III) recommends since 2001 phytosterol enriched functional foods as part of an optimal dietetic prevention strategy in primary and secondary prevention of cardiovascular diseases. The American Heart Association (AHA) has followed and sees phytosterols 'as a therapeutic option ... for individuals with elevated cholesterol levels';. Since then other well-esteemed societies such as the Spanish Cardiology Society, the Association of Clinical and Public Health Nutritionists in Finland, and the National Heart Foundation in Australia, to name only a few, have identified phytosterols as an important additional dietary option in the management of hypercholesterolaemia. However, recently released guidelines are more critical of food supplementation with phytosterols and draw attention to significant safety issues

Prediction and Topological Models in Neuroscience

In the last two decades, philosophy of neuroscience has predominantly focused on explanation. Indeed, it has been argued that mechanistic models are the standards of explanatory success in neuroscience over, among other things, topological models. However, explanatory power is only one virtue of a scientific model. Another is its predictive power. Unfortunately, the notion of prediction has received comparatively little attention in the philosophy of neuroscience, in part because predictions seem disconnected from interventions. In contrast, we argue that topological predictions can and do guide interventions in science, both inside and outside of neuroscience. Topological models allow researchers to predict many phenomena, including diseases, treatment outcomes, aging, and cognition, among others. Moreover, we argue that these predictions also offer strategies for useful interventions. Topology-based predictions play this role regardless of whether they do or can receive a mechanistic interpretation. We conclude by making a case for philosophers to focus on prediction in neuroscience in addition to explanation alone

Association of blood lead concentrations with mortality in older women: a prospective cohort study

<p>Abstract</p> <p>Background</p> <p>Blood lead concentrations have been associated with increased risk of cardiovascular, cancer, and all-cause mortality in adults in general population and occupational cohorts. We aimed to determine the association between blood lead, all cause and cause specific mortality in elderly, community residing women.</p> <p>Methods</p> <p>Prospective cohort study of 533 women aged 65–87 years enrolled in the Study of Osteoporotic Fractures at 2 US research centers (Baltimore, MD; Monongahela Valley, PA) from 1986–1988. Blood lead concentrations were determined by atomic absorption spectrometry. Using blood lead concentration categorized as < 8 μg/dL (0.384 μmol/L), and ≥ 8 μg/dL (0.384 μmol/L), we determined the relative risk of mortality from all cause, and cause-specific mortality, through Cox proportional hazards regression analysis.</p> <p>Results</p> <p>Mean blood lead concentration was 5.3 ± 2.3 μg/dL (range 1–21) [0.25 ± 0.11 μmol/L (range 0.05–1.008)]. After 12.0 ± 3 years of > 95% complete follow-up, 123 (23%) women who died had slightly higher mean (± SD) blood lead 5.56 (± 3) μg/dL [0.27(± 0.14) μmol/L] than survivors: 5.17(± 2.0) [0.25(± 0.1) μmol/L] (<it>p </it>= 0.09). Women with blood lead concentrations ≥ 8 μg/dL (0.384 μmol/L), had 59% increased risk of multivariate adjusted all cause mortality (Hazard Ratio [HR], 1.59; 95% confidence interval [CI], 1.02–2.49) (p = 0.041) especially coronary heart disease (CHD) mortality (HR = 3.08 [CI], (1.23–7.70)(p = 0.016), compared to women with blood lead concentrations < 8 μg/dL(< 0.384 μmol/L). There was no association of blood lead with stroke, cancer, or non cardiovascular deaths.</p> <p>Conclusion</p> <p>Women with blood lead concentrations of ≥ 8 μg/dL (0.384 μmol/L), experienced increased mortality, in particular from CHD as compared to those with lower blood lead concentrations.</p