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Notes: All available controlled studies of warm versus cold and antegrade versus retrograde delivery of cardioplegia were reviewed to assess the incidence of perioperative stroke and adverse neuropsychological outcomes. Nine randomized trials and substudies and two studies with immediate historical consecutive controls reported neurological outcomes and were described as warm versus cold. Pooled event rates for perioperative stroke were 1.5% for warm antegrade, 3.14% for warm retrograde, 1.7% for cold antegrade, and 0% to 1.2% for cold retrograde. Examining within trial differences, only one study showed a significant disadvantage to warm 4.5% versus cold 1.4% on incidence of perioperative stroke, but the design does not permit determination of whether the difference is due to systemic temperature, retrograde coronary perfusion, or other factors. Furthermore, if only warm (〉 33°C) versus cold (〈 30°C) systemic perfusion is examined in all studies for the incidence of stroke irrespective of cardioplegia temperature or antegrade versus retrograde coronary perfusion (warm 2.1%; cold 1.6%), the above study remains a significant outlier. This suggests that the differences found are unlikely to be due to temperature but may be related to antegrade versus retrograde coronary perfusion. Review of randomized trials evaluating neuropsychological function post-cardiopulmonary bypass (post-CPB) also failed to reveal any advantage related to temperature of systemic perfusion. Since manipulations that are most likely to give rise to cerebral embolization are uniformly carried out at normothermia at the beginning and end of the operation, it is not entirely unexpected that the incidence of neurological events was found to be independent of the temperature of CPB. Because stroke is both too rare and too variable in magnitude by chance alone, no studies to date have adequately assessed stroke severity in relation to systemic perfusion temperature or mode and route of cardioplegia delivery.

Notes: Björkman L, Pedersen NL, Lichtenstein P: Physical and mental health related to dental amalgam fillings in Swedish twins.Abstract In the past years increasing attention has been paid to possible adverse health effects of mercury exposure from dental amalgam fillings. To evaluate possible health effects from amalgam fillings, dental status registered by specially trained nurses was obtained from 587 subjects included in the ongoing Swedish Adoption/ Twin Study of Aging (SATSA). Data on physical and mental health were collected and memory function tested. Mean age was 66 years (SD 9, range 46–89). In the entire material, 25% of the individuals had no own teeth and in the group with own teeth the median number of teeth surfaces filled with dental amalgam was 15 (range 0–65). Analyses of associations between number of surfaces filled with dental amalgam and a number of scales estimating somatic and mental health and memory functions were performed both for the entire group and for individuals having at least 12 teeth. Regardless of the sample, no negative effects on physical or mental health were found from amount of dental amalgam, even after controlling for age, gender, education and number of remaining teeth. When using a co-twin control design with twin pairs discordant for amalgam exposure, no negative health effects associated with dental amalgam were detected. This study does not indicate any negative effects from dental amalgam on physical or mental health or memory functions in the general population over 50 years of age.

Notes: Density functional (DF) calculations have been performed for lithium clusters Lin and their monoxides LinO with up to ten atoms. There are numerous stable structures, and new isomers have been found in each family. The structural patterns of the homonuclear and oxide clusters are quite distinct. The combination of DF calculations with molecular dynamics (MD) sheds light on the observed pseudorotation of Li3 and Li5. We compare with available experimental data and discuss the bonding and structural patterns in the clusters and their oxides, which are often described as "hyperlithiated." © 1997 American Institute of Physics.

Notes: Background Human basophils undergo anaphylactic degranulation, characterized by extrusion of membrane-free granules, and piecemeal degranulation, characterized by progressive removal of granule contents in the absence of granule extrusion. F-Met peptide stimulates a degranulation continuum in human basophils that includes both forms of secretion. Charcot-Leyden crystal protein is stored in tbe granules of unstimulated human basopbils.Objective The objective of this study was to determine the subcellular localization of the Charcot-Leyden crystal protein in individual morphological basophil phenotypes that are stimulated by f-Met peptide and are associated with secretion.Methods A post-embedding immunogold analysis was used to detect changes in the subcellular sites of Charcot-Leyden crystal protein in human basophils stimulated with f-Met peptide. Human basophils from nonnal donors were purified by countercurrcnt centrifugal elutriation and Percoll density gradients, stimulated to degranulate with 1 μm f-Met peptide (or incubated in buffer controls), and recovered for histamine assay, electron microscopy and immunogold labelling. Specificity controls Included omission of the primary antibody and substitution of the primary antibody with non-immune normal rabbit IgG or with Charcot-Leyden crystal protein-Sepharose-absorbed primary antibody.Results The results showed new sites of labelling and different densities of labelling for Charcot-Leyden crystal protein in distinctive basophil phenotypes stimulated by f-Met peptide. New sites for Charcot-Leyden crystal protein included nucleus, cytoplasm, degranulation channel, degranulation channel membrane, plasma membrane, and a newly recognized granule population similar to primary granules in eosinophils. These new sites, as well as previously documented sites of Charcot-Leyden crystal protein (granules, intragranular Charcot-Leyden crystals, cytoplasmic vesicles) showed variahic labelling when analysed by phenotype. Other sites (besides intragranular Charcot-Leyden crystals) of formed Charcot-Leyden crystals included cytoplasm, degranulation channel, extracellular space and rarely, nucleus. Analysis of cytoplasmic vesicles, total granules and altered granules, and gold particles in subcellular compartments in seven identifiable phenotypes revealed that f-Met peptide stimulated human basophils to empty their granules by transporting Charcot-Leyden crystal protein in vesicles to the plasma membrane in the absence of granule extrusion in cells exbibiting piecemeal degranulation. In cells exhibiting anaphylactic degranulation. gold-labelled Charcot-Leyden crystals were extruded to the cells' exterior in concert with granule particles and concentric dense membranes contained within granules. Completely degranulated cells had a high density of plasma membrane gold label that was associated with numerous Correspondence: Ann M. Dvorak MD, Department of Pathology, Beth Israel Hospital, 330 Brookline Avenue, Boston, MA 02215, USA. gold-laden endocytotic cytoplasmic vesicles. Basophils reconstituted their main granule population, within which Charcot-Leyden crystals resided, in part by endocytosis of previously released plasma membrane-bound Charcot-Leyden crystal protein. Completely recovered cells displayed decreased Charcot-Leyden crystal protein labelling of the plasma membrane and vesicle compartments, the presence of a highly labelled new granule subset that resembled Charcot-Leyden crystal protein-containing primary granules in eosinophils, and the highest density of granule and intragranular Charcot-Leyden crystal gold labelling of all phenotypes tbat developed after stimulation.Conclusion Seven individual f-Met peptide-activated human basophil phenotypes labelled by an ultrastructural immunogold method to detect subcellular sites of Charcot-Leyden crystal protein showed changing distributions of this protein which document the capability of human basopbils to undergo complex release and recovery reactions that may be pertinent to the functions of Charcot-Leyden crystal protein and the capabilities of these cells in vivo in a variety of diseases.

Notes: Salmeterol is a long-acting β2-adrenergic agonist that is widely used in the treatment of asthma. It has been suggested that non-bronchodilator actions of salmeterol may contribute to its efficacy.〈section xml:id="abs1-2"〉〈title type="main"〉ObjectiveTo further evaluate the potential non-bronchodilator actions of salmeterol in vivo, using a model of nasal challenge with allergen.〈section xml:id="abs1-3"〉〈title type="main"〉MethodsTwelve asymptomatic subjects with seasonal allergic rhinitis participated in a randomized, double-blind, placebo-controlled crossover trial of the effects of a single dose of 100 μg of salmeterol on the response to allergen challenge. Sneezing and symptom scores, and levels of histamine and albumin in nasal lavages, were measured throughout the protocol. Concentrations of tryptase, prostaglandin D2 and lysozyme were measured during the acute allergic response, while levels of IL-3, IL-5 and IL-8 were measured at later time points. Numbers of eosinophils and of total white blood cells were also recorded.〈section xml:id="abs1-4"〉〈title type="main"〉ResultsSalmeterol did not affect sneezing or symptom scores at any point. During the immediate response to allergen challenge, mast cell activation, reflected by concentrations of histamine, tryptase and prostaglandin D2, and serous glandular secretion, assessed by measurements of lysozyme, were unaffected by salmeterol treatment but vascular permeability, reflected by concentrations of albumin in nasal lavages, was significantly reduced. At later time points, salmeterol had no effect on levels of histamine or albumin and did not affect cellular infiltration. Concentrations of IL-3, IL-5 and IL-8 were not increased by allergen challenge in these subjects, so the effects of salmeterol could not be evaluated.〈section xml:id="abs1-5"〉〈title type="main"〉ConclusionsTreatment with a single dose of salmeterol had no effect on activation of mast cells or cellular infiltration but inhibited vascular permeability. The ability of salmeterol to inhibit antigen-induced vascular permeability may contribute to its therapeutic efficacy in asthma.