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Notes: Abstract Background and Aim: We have shown that cumulative sum (CUSUM) failure analysis may be more sensitive than standard statistical methods in detecting a cluster of adverse patient outcomes after cardiac surgical procedures. We therefore applied CUSUM, as well as standard statistical techniques, to analyze a surgeon's experience with off-pump coronary artery bypass grafting (OPCAB) and on-pump procedures to determine whether the two techniques have similar or different outcomes. Methods: In 320 patients undergoing nonemergent, first time coronary artery bypass grafting, preoperative patient characteristics, rates of mortality and major complications, and ICU and hospital lengths of stay were compared between the on-pump and OPCAB cohorts using Fisher's exact tests and Wilcoxon two sample tests. Predicted mortality and length of stay were determined using previously validated models of the Cardiac Care Network of Ontario. Observed versus expected ratios of both variables were calculated for the two types of procedures. Furthermore, CUSUM curves were constructed for the on-pump and OPCAB cohorts. A multivariable analysis of the predictors of hospital length of stay was also performed to determine whether the type of coronary artery bypass procedure had an independent impact on this variable. Results: The predicted mortality risk and predicted hospital length of stay were almost identical in the 208 on-pump patients ( 2.2 ± 3.9% ; 8.2 ± 2.5 days) and the 112 OPCAB patients ( 2.0 ± 2.2% ; 7.8 ± 2.1 days). The incidence of hospital mortality and postoperative stroke were 2.9% and 2.4% in on-pump patients versus zero in OPCAB patients (p= 0.09 and 0.17, respectively). Mechanical ventilation for greater than 48 hours was significantly less common in OPCAB (1.8%) than in on-pump patients (7.7%, p= 0.04). The rate of 10 major complications was 14.9% in on-pump versus 8.0% in OPCAB patients (p= 0.08). OPCAB patients experienced a hospital length of stay that was a median of 1.0 day shorter than on-pump patients (p= 0.01). The observed versus expected ratio for length of stay was 0.78 in OPCAB patients versus 0.95 in on-pump patients. On CUSUM analysis, the failure curve in OPCAB patients was negative and was flatter than that of on-pump patients throughout the duration of the study. Furthermore, OPCAB was an independent predictor of a reduced hospital length of stay on multivariable analysis. Conclusions: OPCAB was associated with better outcomes than on-pump coronary artery bypass despite a similar predicted risk. This robust finding was documented on sensitive CUSUM analysis, using standard statistical techniques and on a multivariable analysis of the independent predictors of hospital length of stay.(J Card Surg 2002;17:520-528)

Notes: Abstract : The inhibitor of apoptosis (IAP) family of anti-apoptoticgenes, originally discovered in baculovirus, exists in animals ranging frominsects to humans. Here, we investigated the ability of IAPs to suppress celldeath in both a neuronal model of apoptosis and excitotoxicity. Cerebellargranule neurons undergo apoptosis when switched from 25 to 5 mMpotassium, and excitotoxic cell death in response to glutamate. We examinedthe endogenous expression of four members of the IAP family, Xchromosome-linked IAP (XIAP), rat IAP1 (RIAP1), RIAP2, and neuronal apoptosisinhibitory protein (NAIP), by semiquantitative reverse PCR and immunoblotanalysis in cultured cerebellar granule neurons. Cerebellar granule neuronsexpress significant levels of RIAP2 mRNA and protein, but expression of RIAP1,NAIP, and XIAP was not detected. RIAP2 mRNA content and protein levels did notchange when cells were switched from 25 to 5 mM potassium. Todetermine whether ectopic expression of IAP influenced neuronal survival afterpotassium withdrawal or glutamate exposure, we used recombinant adenoviralvectors to target XIAP, human IAP1 (HIAP1), HIAP2, and NAIP into cerebellargranule neurons. We demonstrate that forced expression of IAPs efficientlyblocked potassium withdrawal-inducedN-acetly-Asp-Glu-Val-Asp-specific caspase activity and reduced DNAfragmentation. However, neurons were only protected from apoptosis up to 24 hafter potassium withdrawal, not at later time points suggesting that IAPSdelay but do not block apoptosis in cerebellar granule neurons. In contrast,treatment with 100 μM or 1 mM glutamate did not induce caspase activity and adenoviral-mediated expression of IAPs had no influence on subsequent excitotoxic cell death.

Notes: The binding of metal to humic substances is problematical. The approaches for studying metal binding to organic matter are briefly reviewed. Ion-selective electrodes (Cu2+ and Pb2+) were used to measure metal complexation by a whole peat and an extracted humic acid (HA) fraction. Scatchard plots and calculation of incremental formation constants were used to obtain values for the binding constants for the metals onto both peat and HA. Both the peat and the humic acid had a larger maximum binding capacity for Pb2+ than for Cu2+ (e.g. at pH = 5 HA gave 0·188 mmol Cu2+ g−1 and 0·564 mmol Pb2+ g−1: peat gave 0·111 mmol Cu2+ g−1 and 0·391 mmol Pb2+ g−1). Overall, the humic acid had a larger metal binding capacity, suggesting that extraction caused conformational or chemical changes. The binding constants (K1) for Cu2+ increased with increasing pH in both peat and humic acid, and were larger in the peat at any given pH (e.g. at pH = 5 HA gave log K1= 2·63, and peat gave log K1= 4·47 for Cu2+). The values for Pb2+ showed little change with pH or between peat and humic acid (e.g. at pH = 5 HA gave log K1= 3·03 and peat gave log K1= 3·00 for Pb2+). In the peat, Cu2+ may be more able to bind in a 2:1 stoichiometric arrangement, resulting in greater stability but smaller binding capacity, whereas Pb2+ binds predominantly in a 1:1 arrangement, with more metal being bound less strongly. Whole peat is considered to be more appropriate than an extracted humic acid fraction for the study of heavy metal binding in organic soils, as this is the material with which metals introduced into an organic soil would interact under natural conditions.

Notes: High precision electron probe microanalysis (EPMA) has been used to measure the correlation of oxygen deficiency with carrier concentration in thin films of amorphous indium oxide. This has shown that there are ten times as many oxygen vacancies as would be expected from the carrier concentration measurements, giving a doping efficiency of 0.1. It is therefore clear that the doping mechanism is more complex than the usual picture of every oxygen vacancy producing two free electrons.

Notes: Drawing on poststructuralist political ecology, the narratives of two struggles about siting a superquarry are examined to elucidate the complex articulations of community, nature, resistance and identity in play in public debates. Focusing on the discursive formulations of the quarry in the expert language, as well as in the arguments of both local proponents and opponents of the quarries, shows the importance of ontological categories in “environmental” siting disputes. In Harris, these themes rearticulate the histories of dispossession, crofting and religion, as well as complex layers of geographical identity in the various claims to community. In Cape Breton, the rethinking of aboriginal Mi'kmaq identity was stimulated by revived interest in the religious traditions linked to the sacred site near the proposed quarry. In light of these findings, the complexity and active rearticulation of local “community” as political resistance are emphasised and the difficulties of thinking about sustainability highlighted.

Notes: Day care patients at Law Hospital, who had received either a general or a local anaesthetic in conjunction with minor surgery, were assessed by five tests of mental junction before surgery and before discharge from hospital some hours after surgery. These patients did not perform differently from control patients, who were subjected to the same two testing sessions, without intervening surgery or anaesthesia. It was concluded that the day cases were quite capable of normal cognitive functioning at the time of their discharge and that the procedures followed by the hospital for the discharge of day cases are generally adequate.