What are RBC-transfusion-dependence and -independence?

The term RBC-transfusion-dependence is widely-used by hematologists to describe a condition of severe anemia typically arising when erythropoiesis is reduced such that a person continuously requires ≥1 RBC-transfusions over a specified interval. Defining a person as RBC-transfusion-dependent has important implications in diverse hematological disorders especially because it strongly-correlated with decreased survival. Conversely, becoming RBC-transfusion-independent or receiving fewer RBC-transfusions over a specified interval is defined as improvement or response in many disease- and/or therapy-setting. Whether this correlates with improved survival is controversial. We used a structured expert-panel consensus panel process to define RBC-transfusion-dependence and -independence or improvement. We suggest these definitions may prove useful to persons studying or treating these diseases.

Timely Troponins Avoid Admissions: Clinical Assessment of Undifferentiated Chest Pain

Background

Undifferentiated chest pain is a common presentation to acute medicine units. Targeted appropriately timed troponin analysis may reduce unnecessary admissions and relieve bed shortages. We investigated how reliably cardiac chest pain was identified clinically, whether patients had appropriately timed cardiac enzyme analysis, and implications upon rates of admission.

Method

A prospective data collection was completed on 100 consecutive patients admitted with undifferentiated chest pain to an acute receiving unit over 41 days. We excluded patients with acute coronary syndrome or myocardial infarction already confirmed or excluded. Troponin results were retrospectively documented.

Results

Of 100 patients admitted, 67 were thought to have cardiac type chest pain as their only or significant differential diagnosis, and 10 were subsequently confirmed as ACS or MI. Not all patients with cardiac type chest pain were assessed in accordance with SIGN guidelines. 38 patients were admitted overnight solely to await the result of troponin analysis, with a total of 411.5 hours spent waiting at an estimated cost of over £7400.

Conclusion

This study supports the extension of hours of troponin analysis or instant point of care (bedside) cardiac enzyme testing as a cost effective measure, warranting further examination in terms of laboratory service provision.

Adaptive passive fathometer processing

Recently, a technique has been developed to image seabed layers using the ocean ambient noise field as the sound source. This so called passive fathometer technique exploits the naturally occurring acoustic sounds generated on the sea-surface, primarily from breaking waves. The method is based on the cross-correlation of noise from the ocean surface with its echo from the seabed, which recovers travel times to significant seabed reflectors. To limit averaging time and make this practical, beamforming is used with a vertical array of hydrophones to reduce interference from horizontally propagating noise. The initial development used conventional beamforming, but significant improvements have been realized using adaptive techniques. In this paper, adaptive methods for this process are described and applied to several data sets to demonstrate improvements possible as compared to conventional processing.

High pressure study of BaFe2As2--the role of hydrostaticity and uniaxial stress

We investigate the evolution of the electrical resistivity of BaFe(2)As(2) single crystals with pressure. The samples used were from the same batch, grown using a self-flux method, and showed properties that were highly reproducible. Samples were pressurized using three different pressure media: pentane-isopentane (in a piston-cylinder cell), Daphne oil (in an alumina anvil cell) and steatite (in a Bridgman cell). Each pressure medium has its own intrinsic level of hydrostaticity, which dramatically affects the phase diagram. An increasing uniaxial pressure component in this system quickly reduces the spin density wave order and favours the appearance of superconductivity, which is similar to what is seen in SrFe(2)As(2).

Pelvic vein reflux in female patients with varicose veins: comparison of incidence between a specialist private vein clinic and the vascular department of a National Health Service district general hospital

Objectives

Mounting evidence suggests that pelvic vein reflux is an important contributing factor to recurrent varicose veins. We compared the incidence in our specialist private unit (Unit A) with that of a District General Hospital (Unit B).

Methods

Results of all female patient lower limb duplex ultrasound (LLDUS) and transvaginal pelvic ultrasound (TVUS) scans performed over a one-year period were retrospectively reviewed. Patients with refluxing veins emanating from the abdomen or pelvis on LLDUS (non-saphenous reflux) routinely proceeded to TVUS in Unit A.

Results

In Unit A, non-saphenous reflux on LLDUS was present in 90–462 female patients (19.5%). In 81.1% of these, TVUS confirmed reflux in truncal pelvic veins (incidence 15.8%). In Unit B, non-saphenous reflux was present in 60–279 female patients (21.5%).

Conclusion

One in five women presenting with varicose veins have reflux of non-saphenous origin. This is the case in specialist and non-specialist units. One in six has associated pelvic vein reflux.

179. CHARACTERISATION OF THE IN VITRO FUNCTION OF ACTIVIN AC

Activins are members of the TGF-β superfamily that signal via type II and type I receptor subunits and intracellular Smads1. Activin A stimulates FSH release from the pituitary and is also a potent growth and differentiation factor in many physiological systems2. Over-expression of the activin-βC subunit in vitro leads to a reduction in activin A and an increase in activin AC3. Transgenic mice over-expressing activin-βC show decreased circulating activin A, implying that activin AC may also be formed in vivo4. Recently recombinant activin AC has become available, therefore this study examines the in vitro function and mechanism of action of activin AC. Activin AC stimulates FSH release in LβT2 cells and is a negative growth regulator in LNCaP cells, however the potency of activin AC is 8-10 fold less than activin A. Incubation of LNCaP cells with activin receptor antibodies (ALK4, ActRIIA, ActRIIB) abolishes the growth inhibitory effects of activin AC. Activin AC binds to ActRIIB, however a 20-30 fold decrease in both the potency and affinity of activin AC is evident compared to activin A. In addition, activin AC increases Smad-2 phosphorylation. These results indicate activin AC utilises the same receptors and intracellular signalling molecules as activin A. The activin A antagonists, follistatin and activin C4, also antagonise the growth inhibitory effects of activin AC and reduce Smad-2 phosphorylation and Smad-4 expression. This study shows for the first time that the in vitro function of activin AC is similar to activin A, albeit at a lower potency and provides the impetus to determine the physiological role of activin AC in vivo.

Management of Cannabis and Psychostimulant Use among General Practice Patients

While regular and heavy cannabis and psychostimulant use has been associated with significant health and psychological impairments, the extent to which their use is being identified and managed by general practitioners (GPs) remains unclear. The aim of this study was to explore the management of cannabis- and psychostimulant-related problems in Australian general practice. Data from the Bettering the Evaluation and Care of Health (BEACH) study of general practice between April 2000 and March 2007 were analysed. BEACH is an ongoing national study of general practice activity in Australia. It was estimated that during this period GPs in Australia managed illicit drug use about 55,000 times per year and that cannabis and psychostimulants made up 3.2% and 1.6%, respectively, of all encounters at which the illicit drug was specified. The only difference in patient demographics between patients in the two drug groups was that cannabis users were younger than psychostimulant users. Cannabis users were more likely to be managed concurrently for psychotic symptoms but less likely to be treated with antipsychotics. Conversely, patients using psychostimulants were more likely to be prescribed an antipsychotic and/or an anxiolytic for their presenting drug problem. These results suggest that GPs do manage problematic cannabis and psychostimulant use among their patients, and thus should be supported in carrying out appropriate screening, intervention and referral.

Evaluation of the Genplex SNP typing system and a 49plex forensic marker panel

Using a 52 SNP marker set previously developed for forensic analysis, a novel 49plex assay has been developed based on the Genplex typing system, a modification of SNPlex chemistry (both Applied Biosystems) using oligo-ligation of pre-amplified DNA and dye-labeled, mobility modified detection probes. This gives highly predictable electrophoretic mobility of the allelic products generated from the assay to allow detection with standard capillary electrophoresis analyzers. The loci chosen comprise the 48 most informative autosomal SNPs from the SNPforID core discrimination set supplemented with the amelogenin gender marker. These SNPs are evenly distributed across all 22 autosomes, exhibit balanced polymorphisms in three major population groups and have been previously shown to be effective markers for forensic analysis. We tested the accuracy and reproducibility of the Genplex system in three SNPforID laboratories, each using a different Applied Biosystems Genetic Analyzer. Genotyping concordance was measured using replicates of 44 standardized DNA controls and by comparing genotypes for the same samples generated by the TaqMan, SNaPshot and Sequenom iPLEX SNP typing systems. The degree of informativeness of the 48 SNPs for forensic analysis was measured using previously estimated allele frequencies to derive the cumulative match probability and in paternity analysis using 24 trios previously typed with 18 STRs together with three CEPH families with extensive sibships typed with the 15 STRs in the Identifiler kit.

A unified definition of clinical resistance/intolerance to hydroxyurea in essential thrombocythemia: results of a consensus process by an international working group

A widely accepted definition of resistance or intolerance to hydroxyurea (HU) in patients with essential thrombocythemia (ET) is lacking. An international working group (WG) was convened to develop a consensus formulation of clinically significant criteria for defining resistance/intolerance to HU in ET. To this aim, an analytic hierarchy process (AHP), a multiple-attribute decision-making technique, was used. The steps consisted of selecting the candidate criteria for defining resistance/intolerance; identifying the motivations that could influence the preference of the WG for any individual criterion; comparing the candidate criteria in a pair-wise manner; and grading them according their ability to fulfill the motivations. Every step in the model was derived by questionnaires or group discussion. The WG proposed that the definition of resistance/intolerance should require the fulfillment of at least one of the following criteria: platelet count greater than 600,000/micro l after 3 months of at least 2 g/day of HU (2.5 g/day in patients with a body weight over 80 kg); platelet count greater than 400,000/micro l and WBC less than 2500/micro l or Hb less than 10 g/dl at any dose of HU; presence of leg ulcers or other unacceptable muco-cutaneous manifestations at any dose of HU; HU-related fever.

The Eighth International Childhood Acute Lymphoblastic Leukemia Workshop ('Ponte di legno meeting') report: Vienna, Austria, April 27-28, 2005

The International Acute Lymphoblastic Leukemia Working Group, the so-called 'Ponte di Legno Workshop' has led to substantial progress in international collaboration in leukemia research. On April 27-28, 2005, the 8th Meeting was held in Vienna, Austria, to continue the discussions about special common treatment elements in randomized clinical trials, ethical and clinical aspects of therapy. Furthermore, collaborative projects of clinical relevance with special emphasis on rare genetic subtypes of Childhood ALL were established. The following report summarizes the achievements and aspects of possible future cooperation.