Quantifying morphological heterogeneity: a study of more than 1 000 000 individual stored red blood cells.

BACKGROUND AND OBJECTIVES: The morphology of red blood cells (RBCs) deteriorates progressively during hypothermic storage. The degree of deterioration varies between individual cells, resulting in a highly heterogeneous population of cells contained within each RBC unit. Current techniques capable of categorizing the morphology of individual stored RBCs are manual, laborious and error-prone procedures that limit the number of cells that can be studied. Our objective was to create a simple, automated system for high-throughput RBC morphology classification. MATERIALS AND METHODS: A simple microfluidic device, designed to enable rapid, consistent acquisition of images of optimally oriented RBCs, was fabricated using soft lithography. A custom image analysis algorithm was developed to categorize the morphology of each individual RBC in the acquired images. The system was used to determine morphology of individual RBCs in several RBC units stored hypothermically for 6-8 weeks. RESULTS: The system was used to automatically determine the distribution of cell diameter within each morphological class for >1 000 000 individual stored RBCs (speed: >10 000 cells/h; accuracy: 91·9% low resolution, 75·3% high resolution). Diameter mean and standard deviation by morphology class were as follows: discocyte 7·80 ± 0·49 µm, echinocyte 1 7·61 ± 0·63 µm, echinocyte 2 7·02 ± 0·61 µm, echinocyte 3 6·47 ± 0·42 µm, sphero-echinocyte 6·01 ± 0·26 µm, spherocyte 6·02 ± 0·27 µm, stomatocyte 1 6·95 ± 0·61 µm and stomatocyte 2 7·32 ± 0·47 µm. CONCLUSIONS: The automated morphology classification procedure described in this study is significantly simpler, faster and less subjective than conventional manual procedures. The ability to evaluate the morphology of individual RBCs automatically, rapidly and in statistically significant numbers enabled us to perform the most extensive study of stored RBC morphology to date.

Lumbar Puncture: Creation and Resident Acceptance of a Low-Cost, Durable, Reusable Fluoroscopic Phantom with a Fluid-Filled Spinal Canal for Training at an Academic Program.

Simulation-based medical training provides learners a method to develop technical skills without exposing patients to harm. Although fluoroscopic phantoms are already adopted in some areas of radiology, this has historically not been for lumbar puncture. Commercially available phantoms are expensive. We report a cost-effective, accessible solution by creation of an inexpensive phantom for resident training to perform fluoroscopically guided lumbar puncture, as well as instructions on how to make a phantom for residency education. An anthropomorphic ballistics-gel phantom that contains a plastic lumbar vertebral column and simulated CSF space was created. Radiology residents with minimum or no experience with fluoroscopically guided lumbar punctures were given a brief education and practiced fluoroscopically guided lumbar punctures on the phantom. A survey from the residents was then done. The phantom was qualitatively quite durable and deemed adequate for educational purposes. All the residents surveyed expressed the desire to have this phantom available and it increased comfort, knowledge, and perceived likelihood of success. Few articles have been published that focused on low-cost phantom creation for fluoroscopic-procedure training. This study supports the benefits of using phantoms for fluoroscopic training as well as step-by-step instructions for creation of this phantom. The residents responded positively and felt more confident in their fluoroscopically guided techniques. The ability to make a long-term training device for resident education would be inexpensive and relatively easy to implement in academic programs.

The Akoya pearl oyster shell as an archival monitor of lead exposure.

The Akoya pearl oyster (Pinctada imbricata) was experimentally exposed to (a) constant levels of lead (Pb) at 180 microg L(-1) for nine weeks, or (b) two short term (pulse) exposures of Pb at 180 microg L(-1) (three weeks each) with an intervening depuration period (three weeks), to assess its utility as an (i) accumulative monitor of Pb contamination and an (ii) archival monitor for discriminating constant versus pulsed Pb exposure events. P. imbricata showed similar reductions in growth (based on shell morphology and wet weight) and Pb accumulation patterns for whole tissue and shell in response to both Pb exposure regimes. Thus the whole oyster was deemed an inappropriate accumulative monitor for assessing short-term temporal variation of Pb exposure and effect. However, using secondary ion mass spectrometry, Pb was shown to accumulate in the successively deposited nacreous layers of the shell of P. imbricata, documenting the exposure history of constant versus pulsed Pb events. Patterns of Pb deposition not only reflected the frequency of Pb exposure events but also their relative durations. Thus, the shell of P. imbricata may be employed as a suitable biological archive of Pb exposure.

Discrimination or discretion? Exploring dentists' views on treating patients with hepatitis C.

BACKGROUND: People with hepatitis C (over 259 000 Australians) experience stigma and discrimination, whether perceived or actual, in health care settings. They are less likely to access health care, presenting a major barrier to preventive care and treatment. This study aims to identify factors contributing to such discrimination, barriers to optimal care and strategies to overcome these. METHODS: A purposive sample of 25 Victorian dentists took part in semi-structured interviews to investigate their experiences and attitudes in providing care to people with hepatitis C. Interviews were taped, transcribed and coded for thematic analysis. RESULTS: All dentists interviewed were aware of Standard Precautions. However, there were some who changed practices when seeing a client with hepatitis C, suggesting that they lack confidence in Standard Precautions. When prompted, these dentists were concerned that patients may perceive these actions as discriminatory. All participants, including a small minority who expressed negative views about injecting drug users, felt a professional obligation to treat all patients. CONCLUSIONS: Most dentists have appropriate attitudes regarding patients with blood-borne viruses. However, it is important for dentists to understand how their actions may be interpreted by those who feel sensitive about their status. Dentists need to feel genuinely confident about Standard Precautions and have a realistic view of the infection risk posed by patients with blood-borne viruses.

The impact of injecting drug use status on hepatitis C-related referral and treatment.

More than 160,000 people are living with chronic hepatitis C virus (HCV) infection in Australia, however, rates of medical treatment are low. The aim of this study is to examine uptake and predictors of HCV-related health care services among a community-based sample of people with HCV. A self-administered questionnaire was completed by a largely non-clinical sample of 362 women and 308 men with HCV living in the state of Victoria. Analyses were performed according to injecting drug use (IDU) status: no history of injecting (non-IDUs), previous history of injecting (past-IDUs) and current (within the last 12 months) history of injecting (current IDUs). Bivariate and multivariate predictors of referral to a specialist liver clinic were also assessed. Fifty-one percent of participants were current IDUs, 33% past-IDUs and 16% non-IDUs. Fifty-two percent of women and 37% of men reported ever being referred to a specialist liver clinic and 18% of women and 20% of men reported previous HCV antiviral therapy. Although there were many factors related to an increased likelihood of referral (e.g. being female, longer time since diagnosis, longer consultation time at diagnosis, experiencing HCV-related symptoms), multivariate analysis revealed that not being a current IDU and seeing a GP specifically for HCV were the most important independent predictors of referral. For those who had been referred to a liver clinic, a history of IDU was associated with a lower chance of receiving antiviral therapy. IDU status is associated with both referral and treatment. The extension of HCV treatment services to involve GPs and drug and alcohol practitioners should be explored as models to improve access to antiviral therapy.

Quantification of in situ nutrient and heavy metal remediation by a small pearl oyster (Pinctada imbricata) farm at Port Stephens, Australia.

The use of pearl oysters has recently been proposed as an environmental remediation tool in coastal ecosystems. This study quantified the nitrogen, phosphorus and heavy metal content of the tissue and shell of pearl oysters harvested from a small pearl oyster farm at Port Stephens, Australia. Each tonne of pearl oyster material harvested resulted in approximately 703 g metals, 7452 g nitrogen, and 545 g phosphorus being removed from the waters of Port Stephens. Increasing current farm production of 9.8 tyr(-1) to 499 tyr(-1) would balance current nitrogen loads entering Port Stephens from a small Sewage Treatment Plant (STP) located on its southern shores. Furthermore, manipulation of harvest dates to coincide with oyster condition would likely remove substantially greater quantities of nutrients. This study demonstrates that pearl aquaculture may be used to assist in the removal of pollutants from coastal waters while producing a commercially profitable commodity.

Update on D-ala-peptide T-amide (DAPTA): a viral entry inhibitor that blocks CCR5 chemokine receptors.

Peptide T, named for its high threonine content (ASTTTNYT), was derived by a database search which assumed that a relevant receptor binding epitope within env (gp120) would have sequence homology to a known signaling peptide. Binding of radiolabeled gp120 to brain membranes was displaced by peptide T and three octapeptide analogs (including "DAPTA", Dala1-peptide T-amide, the protease-resistant analog now in Phase II clinical trials) with the same potency that these four octapeptides blocked infectivity of an early passage patient isolate. This 1986 report was controversial due to a number of laboratories' failure to find peptide T antiviral effects; we now know that peptide T is a potent HIV entry inhibitor selectively targeting CCR5 receptors with minimal effects on the X4 tropic lab adapted virus exclusively in use at that time. Early clinical trials, which demonstrated lack of toxicity and focused on neurological and neurocognitive benefits, are reviewed and data from a small ongoing Phase II trial--the first to assess peptide T's antiviral effects--are presented. Studies using infectivity, receptor binding, chemotaxis, and blockade of gp120-induced neurotoxicity in vitro and in vivo are reviewed, discussed and presented here. Peptide T and analogs of its core pentapeptide, present near the V2 stem of numerous gp120 isolates, are potent ligands for CCR5. Clinical data showing peptide T's immunomodulation of plasma cytokine levels and increases in the percentage of IFNgamma secreting CD8+ T cells in patients with HIV disease are presented and suggests additional therapeutic mechanisms via regulation of specific immunity.

Functional characterization of HUVEC-CS: Ca2+ signaling, ERK 1/2 activation, mitogenesis and vasodilator production.

While many endothelial cell lines exist, few are of human origin with characteristics close to the parent endothelial cell. We derived a subline (HUVEC-CS) of immortalized human umbilical vein endothelial cells (HUVEC-C) that proliferate in standard growth media and exhibit positive acetylated low-density lipoprotein (AcLDL) uptake, express eNOS, CD31 and ve-cadherin, and spontaneously form capillary-like structures when grown on Matrigel. HUVEC-CS also maintain endothelial cell characteristics at the level of mitogenesis, kinase activation and vasodilator production. Like primary HUVEC cells, HUVEC-CS express many of the key proteins necessary for vasodilator production, including epithelial nitric oxide synthase (eNOS), HSP 90, cav-1 and -2, cPLA2, and COX-1 and -2. Prostaglandin I synthase (PGIS) was not detectable by Western blot analysis, consistent with primary HUVEC in which PGI2 production is minimal. Receptors were detected for angiotensin II (AII), bradykinin, ATP and growth factors. ATP induced a dose- and time-dependent rise in the intracellular free Ca2+ concentration ([Ca2+]i). Initially, ATP stimulates P2Y receptors rather than P2X receptors, as demonstrated by the inability of ATP to initiate a Ca2+ response subsequent to emptying of the internal Ca2+ stores by thapsigargin. AII, bradykinin, epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) also caused a rise in [Ca2+]i in a subset of the cells. ATP, basic fibroblastic growth factor (bFGF), EGF and VEGF induced mitogenesis and caused a rise in ERK 2 activation within 10 min. L-Arginine to L-citrulline conversion assays showed that ATP, EGF and VEGF induced a significant rise in eNOS activity, and this correlates with an ability to induce Ca2+ mobilization and ERK 2 activation. In conclusion, HUVEC-CS are indeed endothelial cells and appear to be functionally very similar to primary HUVEC. These cells will prove a valuable tool for future studies in both basic and therapeutic sciences.

Between two wars. Psychoanalysis in Europe, 1918-1938.

In outline form, the major centers of European psychoanalysis have been described: from the first post-war meeting of the International Psychoanalytic Association in Budapest, 1918, when institutes for analytic training were proposed, to the Anschluss in March 1938, when Vienna was occupied by the Nazis and psychoanalysis on the Continent was extinguished for almost a decade. The emphasis has been on the organization and structure of institutes, chiefly Berlin, Vienna, and London, in that order. As an institutional history, both biographic details and theoretical issues have been kept to a minimum. The exceptions have been the controversies about lay analysis, Melanie Klein's developmental theories, and Ferenczi's innovations in technique. In these issues, some detail is necessary to understand how one institute differed from another within the analytic movement, although they were unified by the International Psychoanalytic Association (IPA). The history of the British analytic community, which survived World War II intact, is highly condensed, and Prague, Budapest, and Paris are briefly mentioned. A history of psychoanalysis in Russia has yet to be written, from its early flowering before and during the Bolshevik revolution (1918-1920) to its swift repression under Stalin in the later 1920s. Among the conclusions to be drawn from these data is the extent to which political events influenced the development of analysis, then in its most expansive phase. Even theory was affected by history, as in the evolution of Freud's repetition-compulsion from observations on the traumatic neuroses of war. Socioeconomic conditions influenced the propagation of analytic ideas, favorably in post-war Berlin, adversely in Vienna. Each country evolved the kind of analysis that suited it best, with a variety of institutions within the same international movement. The causes of these variations in psychoanalytic institutes are a matter for speculation. Some analytic historians have linked Freud's advocacy of lay analysis to his estrangement from the medical establishment of Vienna, or to his dread that analysis might become the "house-maid" of medicine and psychiatry, as in America. Others find the roots of Freud's attitudes toward medicine in his conflicts about becoming a doctor, his yearning for philosophic speculation, which he "sternly held in check." In contrast, psychoanalysis in the United States was always committed to medical education as a prerequisite for becoming an analyst, and, in 1926, there was a sharp break from Freud's defense of lay analysis. Hale, among others, has suggested that the American "medical fixation" was a reaction to the chaotic state of our nineteenth century medical education, with diploma mills and self-taught healers scattered over a vast continent.(ABSTRACT TRUNCATED AT 400 WORDS)

A community approach to diabetes education in Australia--The Region 8 (Victoria) Diabetes Education and Control Program.

The Australian Region 8 (Victoria) Diabetes Education and Control Program (DECP) is a community-based program which seeks to integrate ambulatory diabetes education programs into primary health care centres. The overall goal of the DECP is to reduce the human and economic costs of diabetes in a health region which covers 25% of the population of Victoria. Several implementation models are being tested and a rigorous evaluation has been built into the program. Diabetes education activities are targeted at 3 levels--the community, persons with diabetes, and health professionals. The DECP may provide of useful model for establishing diabetes and other chronic disease education and control programs, within community settings, in other parts of Australia and other countries.

Trying to keep a balance: the meaning of health and diabetes in an urban aboriginal community.

Although the predominant paradigm of epidemiological investigation continues to focus narrowly on the individual and on individual risk factors, there is a growing body of work that calls for a rethinking of the current epidemiological models. In this paper we illustrate the need for a more comprehensive epidemiological approach towards understanding the risks for diabetes, by exploring the lived experiences of diabetes and lay meanings of risk among Aborigines living in Melbourne, Australia. Ethnographic fieldwork was conducted within the Melbourne Aboriginal community in the state of Victoria over a 22-month period (1994-1996). Melbourne Aborigines see non-insulin dependent diabetes mellitus (NIDDM) as the result of living a life out of balance, a life of lost or severed connections with land and kin and a life with little control over past, present or future. The lay model regarding diabetes that is derived from the narratives of Melbourne Aborigines, consists of three levels of connectedness important in determining an individual's susceptibility not only to diabetes but to all disease--(1) family, (2) community and (3) society. This structure of interactive systems at successive levels from the individual to the population fits within the framework of an ecological paradigm. The strength of ethnography as applied to epidemiology is that it has the capacity to discover previously unknown components of a system at several different levels, and to build models to explain how these components interact. This framework, developed using an ethno-epidemiological approach, has application in other indigenous populations who have been dispossessed of their land, their pasts and their future. There is great potential to apply this approach to the major public health challenges presented by rapid global socio-cultural and environmental change that are impacting negatively on population health.

The social and cultural context of risk and prevention: food and physical activity in an urban Aboriginal community.

One of the key public health challenges facing indigenous and other minority communities is how to develop and implement effective, acceptable, and sustainable strategies for the prevention of non-insulin-dependent diabetes mellitus (NIDDM). In this article, the authors describe how an ethnographic approach was used to contextualize the behavioral risk factors for NIDDM and applied to the development of a more meaningful and appropriate epidemiological risk factor survey instrument for an urban Aboriginal population in Australia. The overall research design comprised a mixture of qualitative and quantitative methods. The ethnographic study showed that the complex web of meanings that tie people to their family and community can and should be taken into account in any social epidemiology of health and illness if the findings are to have any effective and long-term potential to contribute to successful public health interventions targeting these behavioral risk factors.

Narratives of risk in occupational health and safety: why the 'good' boss blames his tradesman and the 'good' tradesman blames his tools.

Risk and its control are important themes in occupational health and safety. In the current regulatory framework, risk is conceptualised as a probabilistic expression of hazard potential. However, social meanings of risk in the workplace may be different. The social context of work shapes the ways that risk is understood in the workplace, yet little research in occupational health and safety acknowledges it. A few studies of risk have used qualitative research methods to elicit understandings of risk at work; however, little research explores the experiences of both employers and employees. This study describes the narratives of risk in occupational health and safety of employers and employees in the Victorian painting industry. Using ethnographic methods, we collected data about the contexts in which risk is experienced and the sources of risk that each group identifies. These narratives reveal that risk in the painting industry is constructed through the interactions of three factors: the social context, the hierarchical structure of the industry and the shared assumptions about risk control through the individual skills and responsibilities. The narratives explain why occupational health and safety strategies focusing solely on individual behaviour change or technical measures will be unsuccessful.

Macroalgal biomonitors of trace metal contamination in acid sulfate soil aquaculture ponds.

Earthen shrimp aquaculture ponds are often impacted by acid sulfate soils (ASS), typically resulting in increased disease and mortality of cultured organisms. Production losses have been attributed to either low pH or to elevated concentrations of toxic metals, both direct products of pyrite oxidation in ASS. The standard farm management practice to minimise effects of pyrite oxidation is to maintain pH of pond waters above 5, based on the assumption that dissolved metal bioavailability is negligible at this pH. This study aimed to test the validity of this assumption, and therefore elucidate a possible role of toxic heavy metals in observed decreases in farm productivity. Metal bioaccumulation in four genera of macroalgae, Ulva sp., Enteromorpha sp., Cladophora sp. and Chaetomorpha sp., sampled from ASS-affected shrimp aquaculture ponds were measured using inductively coupled plasma-optical emission spectroscopy (ICP-OES) to assess the relative bioavailability of dissolved metals within the system. Results showed that all four genera of macroalgae accumulated appreciable quantities of Fe, Al, Zn, Cd, Cu, As and Pb. Iron and Al, the most common metals mobilised from ASS, were both accumulated in all algal genera to concentrations three orders of magnitude greater than all other metals analysed. These findings indicate that dissolved heavy metals are indeed bioavailable within the aquaculture pond system. A literature search of heavy metal bioaccumulation by these algal genera revealed concentrations recorded in this study are comparable to highly contaminated environments, such as those exposed to urban, industrial and mining pollution. The results of this study indicate that dissolved metal bioavailability in many earthen shrimp aquaculture ponds may be higher than previously thought.

Pearl aquaculture-profitable environmental remediation?

Bivalve molluscs are filter feeders, with pearl oysters able to filter water at rates up to 25 lh(-1)g(-1) of dry wt. tissue. Since this process leads to rapid bioaccumulation of recalcitrant pollutants such as heavy metals, organochlorine pesticides and hydrocarbons from impacted sites, it has prompted the widespread use of molluscs as biomonitors to quantify levels of marine pollution. This paper proposes pearl oyster deployment as a novel bioremediation technology for impacted sites to remove toxic contaminants, reduce nutrient loads and lower concentrations of microbial pathogens. Estimates extrapolated from the literature suggest that a modest pearl oyster farm of 100 t oyster material per year could remove 300 kg heavy metals plus 24 kg of organic contaminants via deposition into the tissue and shell. Furthermore, it was estimated that up to 19 kg of nitrogen may be removed from the coastal ecosystem per tonne of pearl oyster harvested. Pearl oysters are also likely to filter substantial amounts of sewage associated microbial pathogens from the water column. Method of cultivation and site selection are the key to minimising negative environmental impacts of bivalve cultivation. Deployment of oysters at sites with high nutrient and contaminant loadings would be advantageous, as these compounds would be removed from the ecosystem whilst generating a value-added product. Future potential may exist for harvesting bio-concentrated elements for commercial production.

Health of nations: lessons from Victoria, Australia.

In its white paper The Health of the Nation the government has announced its intention to give more priority to preventive health care. Two examples from Victoria, Australia, show how coordinated legislative and voluntary sector action can have a substantial impact on public behaviour. The introduction and enforcement of strict drink-driving laws and speed limits backed up by forceful television advertisements produced a large reduction in deaths from road traffic accidents, the death rate in relation to the number of vehicles in 1991 being among the lowest in the world. Smoking has also declined in parallel with a phased ban on advertising and use of taxes from tobacco sales to replace tobacco sponsorship of sports and arts and fund health promotion.