Work-related injuries and attendance at a Canadian regional emergency department.

BACKGROUND: Monitoring trends in the burden of illness and injury attributable to work is key in assessing occupational health hazards; however, New Brunswick does not participate in the Canadian National Ambulatory Care Reporting System which itself does not collect details of occupation and industry. AIMS: We set out to determine the proportion of emergency department attendances that were attributable to a work-related cause. We also wanted to evaluate the recording of occupation in the electronic health record system, and to describe the characteristics of patients with a work-related presentation. METHODS: A retrospective observational study over a 1-year period was conducted using an administrative database obtained from Canadian Emergency Department Information System. Descriptive statistics are used to present the analysis of categorical and continuous data. RESULTS: A total of 49 365 patients were included for analysis. Two per cent of patients presented with a self-reported work-related condition. Health care and social assistance, construction, retail trade and manufacturing were the most common industries reported by patients. CONCLUSIONS: This study found the rate of work-related medical conditions to be substantially less than expected, and that occupation was not captured for any patients presenting to the emergency department with a work-related condition, despite a field being available in the electronic health record registration system. We were able to analyse the industry sectors for work-related presentations. The recording and coding of occupation and industry would significantly benefit occupational epidemiology in emergency medicine as well as potentially improving patient outcomes and health system efficiencies.

Non-inferiority of nitric oxide releasing intranasal spray compared to sub-therapeutic antibiotics to reduce incidence of undifferentiated fever and bovine respiratory disease complex in low to moderate risk beef cattle arriving at a commercial feedlot.

Undifferentiated fever, or bovine respiratory disease complex (BRDc), is a challenging multi-factorial health issue caused by viral/bacterial pathogens and stressors linked to the transport and mixing of cattle, negatively impacting the cattle feedlot industry. Common practice during processing at feedlots is administration of antibiotic metaphylaxis to reduce the incidence of BRDc. Nitric oxide (NO) is a naturally occurring nano-molecule with a wide range of physiological attributes. This study evaluated the metaphylactic use of intranasal NO releasing spray (NORS) to control BRDc incidence in calves at low-moderate risk of developing BRDc, arriving at a commercial feedlot as compared to conventional antibiotic metaphylaxis. One thousand and eighty crossbred, multiple-sourced, commingled, commercial, weaned beef calves were screened, enrolled, randomized and treated upon arrival. Animals appearing sick were pulled (from their pen) by blinded pen keepers then assessed for BRDc symptoms; blood samples were taken for haptoglobin quantification and the animals were rescued with an antibiotic. After 35 days both groups showed no significant difference in BRDc incidence (5.2% of animals from NORS group and 3.2% from antibiotic group). Average daily weight gain of animals at day 150 for the NORS cohort was 1.17kg compared to 1.18kg for the antibiotic group (p>0.05). There was no significant difference in mortality in the first 35 days (p=0.7552), however, general mortality over 150 days trended higher in the antibiotic cohort. NORS treatment was shown to be safe, causing neither distress nor adverse effects on the animals. This large randomized controlled study in low-moderate BRDc incidence risk calves demonstrates that NORS treatment, as compared to conventional metaphylactic antibiotics, is non-inferior based on BRDc incidence and other metrics like weight and mortality. These data justify further studies in higher BRDc incidence risk populations to evaluate NORS as an alternative strategy to reduce sub-therapeutic metaphylaxis antibiotic use in beef cattle production.

Potential application of gaseous nitric oxide as a topical antimicrobial agent.

The presence of bacterial colonization in non-healing wounds and burn injuries interferes significantly with the normal process of healing. Recent evidence suggests that nitric oxide (NO) plays an important role in host defense against infection and regulates wound healing and angiogenesis. We investigated the potential application of a medical-grade gaseous form of NO (gNO) as a novel antibacterial agent in wound infection. Using a continuous horizontal-flow delivery system, the antibacterial activity of gNO was tested in vitro against a range of pathogens, including clinical isolates of Staphylococcus aureus, methicillin-resistant S. aureus, Escherichia coli, Group B Streptococcus, Pseudomonas aeruginosa, and Candida albicans. To probe the effect of topical application of gNO on the human skin, the proliferation and extracellular matrix gene expression of human dermal fibroblasts in culture were also analyzed by (3)H-thymidine incorporation assay and Northern blot techniques, respectively. Potent bacteriocidal activity was observed at 200 ppm gNO with an average of 4.1 +/- 1.1 h to completely stop bacterial growth. Interestingly, this dose of gNO did not show any cytotoxic effect in human dermal fibroblasts in culture exposed for up to 48 h. Analysis of gene transcription in fibroblasts revealed a significant increase in MMP-1 mRNA expression as early as 2 h post-exposure to gNO. Although to a lesser degree, a significant reduction in type I procollagen was also observed in the same fibroblasts. The results of this study suggest that exogenous gaseous NO has potent significant antibacterial properties that can be beneficial in reducing bacterial burden in infected wound in burn injuries or non-healing ulcers.

Is it the right ansatz?

This article is a response to Rasmussen et al. [Artificial Life, 7, 329-350], in which the authors suggest that, within a particular simulation "framework," there is a tight correspondence between the complexity of the primitive objects and the emergence of dynamical hierarchies. As an example they report a two-dimensional artificial chemistry that supports the spontaneous emergence of micellar structures, which they classify as third-order structures. We report in this article that essentially comparable phenomena can be produced with relatively simpler primitive objects. We also question the order classification of the micellar structures.

Remarks on autocatalysis and autopoiesis.

The notions of collective autocatalysis and of autopoiesis are clearly related; equally clearly, they are not quite the same. The purpose of this paper is to try to clarify the relationship. Specifically I suggest that autopoiesis can be at least roughly characterized as collective autocatalysis plus spatial individuation. Although some mechanism of spatial confinement or concentration is probably necessary to the effective operation of any collectively autocatalytic reaction network, autopoiesis requires, in addition, that the mechanism for maintaining this confinement should itself be a product of the reaction network--and should thus (?) be capable of separating or individuating otherwise identically organized networks. I suggest an informal heuristic test to discriminate the (merely) collectively autocatalytic from the (properly) autopoietic. Finally, in the light of this, I review a variety of published abstract or model systems, Alchemy, alpha-universes, Tierra, and SCL.

John von Neumann and the evolutionary growth of complexity: looking backward, looking forward...

In the late 1940s John von Neumann began to work on what he intended as a comprehensive "theory of [complex] automata." He started to develop a book length manuscript on the subject in 1952. However, he put it aside in 1953, apparently due to pressure of other work. Due to his tragically early death in 1957, he was never to return to it. The draft manuscript was eventually edited, and combined for publication with some related lecture transcripts, by Burks in 1966. It is clear from the time and effort that von Neumann invested in it that he considered this to be a very significant and substantial piece of work. However, subsequent commentators (beginning even with Burks) have found it surprisingly difficult to articulate this substance. Indeed, it has since been suggested that von Neumann's results in this area either are trivial, or, at the very least, could have been achieved by much simpler means. It is an enigma. In this paper I review the history of this debate (briefly) and then present my own attempt at resolving the issue by focusing on an analysis of von Neumann's problem situation. I claim that this reveals the true depth of von Neumann's achievement and influence on the subsequent development of this field, and further that it generates a whole family of new consequent problems, which can still serve to inform - if not actually define - the field of artificial life for many years to come.

Computing machinery and mentality.

I reconsider the status of computationalism (or, in a weak sense, functionalism): the claim that being a realization of some (as yet unspecified) class of abstract machine is both necessary and sufficient for having genuine, full-blooded, mentality. This doctrine is now quite widely (though by no means universally) seen as discredited. My position is that, though it is undoubtedly an unsatisfactory (perhaps even repugnant) thesis, the arguments against it are still rather weak. In particular, I critically reassess John Searle's infamous Chinese Room Argument and also some relevant aspects of Karl Popper's theory of the Open Universe. I conclude that the status of computationalism must still be regarded as undecided, and that it may still provide a satisfactory framework for research.

Phase I trial of a 90-minute infusion of the fusion toxin DAB486IL-2 in hematological cancers.

DAB486IL-2, a recombinant fusion toxin in which the native receptor binding domain of diphtheria toxin has been replaced with interleukin-2 (IL-2), has displayed significant activity in patients with chemotherapy refractory hematological cancers. To further investigate the safety and antitumor effect of this agent, we conducted a single arm, dose escalation study of a 90-min infusion of DAB486IL-2 daily for 5 days. Patients with cancers of a histology previously reported to express the p55 component of the IL-2 receptor and who could not receive potentially more effective therapy were eligible for enrollment. Fifteen men and 8 women with a median age of 49 years were given a total of 51 courses of DAB486IL-2. The maximum tolerated dose was 0.3 mg/kg/day defined by renal insufficiency associated with hemolysis and thrombocytopenia. The clearance of DAB486IL-2 from serum fit a one-compartment model with a half-life of 11.5 +/- 4.3 (SD) min at the 0.2-mg/kg dose. Two patients sustained a partial response and 4 patients had tumor reduction not qualifying for an objective response. No tumors that were negative for expression of the p55 subunit of the receptor responded to DAB486IL-2 treatment. Reduction in size occurred in 2 tumors in which p55 expression was unknown and 4 patients with tumors that were known to be p55 positive. Dosing determined by specific activity rather than mass also appeared to be an important determinant of response. This study suggests that the presence of p55 expression on tumor cells is necessary, but alone may not be sufficient to achieve a tumor response. The correlation of additional variables such as specific activity of DAB486IL-2 and tumor expression of the p75 subunit of the IL-2 receptor and receptor function will also require further study.