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Background and Objectives The aim of the study was to evaluate a lyophilized serum preparation, 14/300, for its suitability to serve as a World Health Organization ( WHO) Reference Reagent to standardize and control haemagglutination titrations for anti-A and anti-B in serum and plasma, in an international collaborative study. Materials and Methods Serum preparation 14/300 and two plasma-based reserve preparations, 14/304 (high titre anti-A) and 14/208 (high titre anti-B), were titrated by 24 laboratories in 13 countries using direct ( DRT) and indirect ( IAT) haemagglutination techniques. Results There was eightfold to 64-fold variation in reported titres per preparation and method across laboratories, that is, titres extended over 4-7 dilutions, although intralaboratory variability was generally good, with over 90% of replicate titres within a twofold range. There was a reduction in interlaboratory variability when titres of the reserve preparations were adjusted relative to those of the candidate Reference Reagent. Conclusion The establishment of 14/300 as a WHO Reference Reagent for high titre anti-A and anti-B in serum, with nominal anti-A and anti-B titres of 128 for DRT, and nominal anti-A and anti-B titres of 256 for IAT, will facilitate global standardization of haemagglutination titrations for anti-A and anti-B in patient samples and blood components. [ABSTRACT FROM AUTHOR]

Whitewater parks (WWPs) are increasingly popular recreational amenities, but the effects of WWPs on fish habitat and passage are poorly understood. This study investigated the use of a two-dimensional (2-D) model as compared with a three-dimensional (3-D) hydrodynamic model ( flow-3D®) for assessing effects of WWPs on fish habitat. The primary aims of this study were to (1) examine the utility of 3-D modelling versus 2-D modelling in a hydraulically complex WWP and (2) compare modelled habitat quality for resident fishes with actual fish abundance and biomass generated from field sampling surveys. Two reaches of a wadeable river in Colorado were modelled: a natural reach and a reach containing a WWP. A 2-D habitat suitability analysis for juvenile and adult brown trout, juvenile and adult rainbow trout, longnose dace and longnose sucker predicted the same or higher habitat quality in the WWPs than the natural pools for all four species and for all modelled flow rates; however, results from fish sampling found significantly higher fish biomass for all four species in natural pools compared with WWP pools. All hydraulic metrics (depth, depth-averaged velocity, turbulent kinetic energy, 2-D and 3-D vorticity) had higher magnitudes in WWP pools than in natural pools. In the WWP pools, 3-D model results described the spatial distribution of flow characteristics or the magnitude of variables better than 2-D results. This supports the use of 3-D modelling for complex flows found in WWPs, but improved understanding of linkages between fish habitat quality and 3-D hydraulic descriptors is needed. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Safe vascular access is integral to anaesthetic and critical care practice, but procedures are a frequent source of patient adverse events. Ensuring safe and effective approaches to vascular catheter insertion should be a priority for all practitioners. New technology such as ultrasound and other imaging has increased the number of tools available. This guidance was created using review of current practice and literature, as well as expert opinion. The result is a consensus document which provides practical advice on the safe insertion and removal of vascular access devices. [ABSTRACT FROM AUTHOR]

Background and Objectives The aim of the study was to evaluate, in an international collaboration, four lyophilised genomic DNA preparations, selected from genotyped and phenotyped donors by the study organisers, for their suitability to standardise and control blood group genotyping procedures for common ancestral Caucasian and Black African alleles. Materials and Methods Twenty-nine laboratories performed 'blind' testing of replicated ampoules of the candidate reference reagents, RBC1 (10/232), RBC4 (10/236), RBC5 (10/238) and RBC12 (10/234), using a range of genotyping procedures, most commonly classical PCR using allele or sequence specific primers. Results The majority of laboratories reported blood group genotypes in accordance with those determined by the study organisers and the serological phenotypes. Despite an overall high level of accuracy in genotyping, the identified errors and inconsistencies, and the limited genotyping capabilities of many laboratories, confirmed the need for validated reference materials to control test procedures. Conclusions The establishment of RBC1, RBC4, RBC5 and RBC12 as World Health Organization Reference Reagents will facilitate international standardisation of blood group genotyping and ensure that such tests are sufficiently sensitive and specific. [ABSTRACT FROM AUTHOR]

Background and Objectives The aim of the study was to evaluate, in an international collaboration, three lyophilized intravenous immunoglobulin (IVIG) preparations for their suitability to standardize and control haemagglutination testing for anti-A and anti-B in IVIG products. Materials and Methods Twenty-three laboratories tested candidate IVIG reference reagents consisting of a Positive control (07/306), a Negative control (07/308), and a specifically formulated Limit preparation (07/310) to define the maximum (e.g. pharmacopoeial) limits of anti-A and anti-B in IVIG products, where limits are applicable. Laboratories performed direct haemagglutination using papain-treated erythrocytes and/or indirect antiglobulin tests. Results For both methods, there was up to 16-fold variation in anti-A and anti-B titres, although there was good agreement over a two-fold titre range for anti-A and anti-B between laboratories for both 07/306 and 07/310 using the direct method. Comparative titration data for 07/306 and 07/310 indicated that the use of a ‘Limit’ reference reagent would facilitate identification of higher titre batches when the direct haemagglutination method is used. Conclusions The establishment of preparations 07/306, 07/308 and 07/310 as reference reagents by the World Health Organization will facilitate global standardization of haemagglutination tests for anti-A and anti-B, ensure that such tests are sufficiently sensitive and specific, and facilitate identification of batches that exceed maximum recommended levels of anti-A and anti-B. The Commission of the European Pharmacopoeia and the United States Food and Drug Administration have adopted the same reference reagents including the maximal specifications defined by preparation 07/310. [ABSTRACT FROM AUTHOR]

Background and Objectives The aim of the study was to evaluate lyophilized monoclonal IgM anti-A and anti-B preparations for use as international standards (IS) to specify recommended minimum potencies of anti-A and anti-B blood grouping reagents in tube tests. Materials and Methods The candidate IS for minimum potency of anti-A and anti-B blood grouping reagents, codes 03/188 and 03/164, respectively, were evaluated against a wide range of commercial anti-A and anti-B blood grouping reagents in an international collaborative study involving 16 laboratories in nine countries. Laboratories titrated 03/188 and 03/164 in parallel with as many commercial anti-A and anti-B blood grouping reagents, respectively, as were available to them, in tube tests according to specified haemagglutination methodology. Three of these laboratories and a further laboratory also titrated 03/188 and 03/164 in parallel with currently available reference preparations for anti-A and anti-B. The ratios of the mean endpoint titres of the anti-A and anti-B reagents to those of 03/188 and 03/164, respectively, within each laboratory were calculated. Results The ratios of the mean titres of the anti-A reagents to the mean titre of 03/188 within a laboratory fell within 0·062 and 4, i.e. the potencies of the anti-A reagents were between a sixteenth to four times as strong as 03/188. The ratios of the mean titres of the anti-B reagents to the mean titre of 03/164 within a laboratory also fell within 0·062 and 4, with one outlier. Conclusions By international consensus, a 1 in 8 dilution of the candidate IS for anti-A, 03/188, and a 1 in 4 dilution of the candidate IS for anti-B, 03/164, were considered appropriate to define the recommended minimum potencies of anti-A and anti-B blood grouping reagents, respectively, in tube tests. On the basis of these results, preparations 03/188 and 03/164 were established by the World Health Organization as International Standards for Minimum Potency of Anti-A and Anti-B Blood Grouping Reagents respectively, and by the US Food and Drug Administration Center for Biologics Evaluation and Research as Minimum Potency Reference Reagents. [ABSTRACT FROM AUTHOR]

Objective To establish whether visceral fat mass is the most significant variable correlating with insulin resistance and other metabolic parameters in women with polycystic ovary syndrome (PCOS). Design Prospective cross-sectional trial. Setting Reproductive medicine clinic. Population Forty women with anovulatory PCOS. Methods Measurements were taken at recruitment, and analysis was performed to define correlations between the outcome measures and the explanatory variables. Main outcome measures Visceral and subcutaneous fat by computed tomography scan, insulin resistance, anthropometric measures, markers of the metabolic syndrome and androgens. Results Strong linear correlation of visceral fat to insulin resistance ( r= 0.68, P < 0.001) was observed. There were also statistically significant correlations with fasting insulin ( r= 0.73, P < 0.001), homeostasis model assessment β-cell function ( r= 0.50, P= 0.007), triglycerides ( r= 0.45, P= 0.003), high-density lipoprotein cholesterol ( r=−0.42, P= 0.007), urate ( r= 0.47, P= 0.002), Sex hormone binding globulin ( r=−0.39, P= 0.01) and luteinising hormone ( r=−0.32, P= 0.02). There were no significant correlations of testosterone with fat distribution or metabolic parameters. Insulin resistance showed closest correlation to visceral fat mass ( r= 0.68, P < 0.001), then to waist circumference ( r= 0.62, P < 0.001), with the weakest correlation being waist:hip ratio ( r= 0.36, P= 0.01). The best regression model for predicting insulin resistance is with visceral fat mass and triglycerides as the explanatory variables ( r= 0.72, P < 0.001). Conclusions Visceral fat is the most significant variable correlating with metabolic dysfunction in women with PCOS. Our data support the hypothesis that visceral fat either causes insulin resistance or is a very early effect of it. It also implies that reducing visceral fat should reduce insulin resistance which may account for the observations that exercise and weight loss appear to be more effective interventions than pharmacological treatments. The best anthropometric measure of insulin resistance is waist circumference. [ABSTRACT FROM AUTHOR]

Objective To establish whether metformin has a significant action in reducing visceral fat and improving other metabolic parameters in women with polycystic ovary syndrome (PCOS). Design Randomised, double-blind, placebo-controlled trial. Setting Reproductive medicine clinic. Population Forty women with anovulatory PCOS. Methods Participants were randomised into receiving metformin 500 mg three times a day or placebo for 3 months. Main outcome measures Fat distribution was measured by computed tomography scan. Secondary outcome measures included serum indices of the metabolic syndrome and evidence of ovulation. Results We found no significant differences in any of the measures of fat distribution between the placebo and metformin groups. The metformin group had significantly lower total cholesterol ( P= 0.02), low-density lipoprotein cholesterol ( P= 0.02) and cholesterol:high-density lipoprotein cholesterol ratio ( P= 0.05), but there was no statistically significant treatment effect on androgens, insulin, insulin resistance, triglycerides, ovulation or pregnancy. Conclusions Metformin has no clinically significant effect in reducing visceral fat mass, although it does have a beneficial effect on lipids. This trial lends support to the growing evidence that metformin is not a weight loss drug. Metformin might therefore be used as an adjunct to lifestyle modification in women with PCOS, but not as a substitute for it. [ABSTRACT FROM AUTHOR]

Background and Objectives The aim of this study was to evaluate a lyophilized monoclonal immunoglobulin M (IgM) anti-D preparation for use as an International Standard to specify a recommended minimum acceptable potency of anti-D blood-grouping reagents. Materials and Methods The candidate International Standard (99/836) for specifying the minimum potency of anti-D blood-grouping reagents was evaluated against a wide range of commercial anti-D blood-grouping reagents in an international collaborative study involving 20 laboratories in 13 countries. Laboratories titrated reconstituted 99/836, in parallel with as many commercial anti-D blood-grouping reagents as were available to them, in tube tests according to specified haemagglutination methodology for low-protein (e.g. monoclonal IgM) and high-protein (e.g. polyclonal) reagents. The ratios of the mean end-point titres of the reagents to that of 99/836 within each laboratory were calculated. Results The ratios of the mean titres of the low-protein reagents to the mean titre of 99/836 within a laboratory fell between 0·25 and 2 for 43 of the 45 low-protein anti-D reagents tested (i.e. the potencies of the low-protein reagents compared with 99/836 were between a 1 : 4 dilution of 99/836 to twice as potent as 99/836). The ratios of the mean titres of the high-protein reagents to the mean titre of 99/836 within a laboratory fell within 0·125 and 1 for eight out of the 10 high protein reagents tested. Conclusions By international consensus, a 1 : 3 dilution of reconstituted 99/836 was deemed appropriate to define a recommended minimum acceptable potency of low-protein anti-D blood-grouping reagents. A 1 : 8 dilution of reconstituted 99/836 was deemed appropriate to define a recommended minimum acceptable potency of high-protein anti-D blood-grouping reagents. On the basis of the results presented here, 99/836 was established by the World Health Organization as the 1st International Standard for specifying the minimum potency of anti-D blood-grouping reagents, in tube tests. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate a lyophilized intravenous immunoglobulin (IVIG) preparation containing anti-D (02/228; nominal reciprocal titre of 8) for its suitability to define the maximum limit of anti-D in IVIG products when used in a proposed reference method of direct haemagglutination of papain-treated erythrocytes, in an international collaborative study.Twenty laboratories tested 02/228 along with a negative control IVIG preparation and four IVIG samples containing different levels of anti-D. Nineteen laboratories performed direct haemagglutination methodology using papain-treated erythrocytes; five of these laboratories and one additional laboratory performed their in-house haemagglutination methodology (all indirect antiglobulin tests).The mode titre of 02/228, obtained by using the proposed reference method, was 8 (62·5% of tests). However, there was wide variation in haemagglutination titres between laboratories for three of the four samples. Correcting the titres of the samples relative to those of the proposed reference preparation reduced the interlaboratory variability and increased the frequency of the mode titres in three out of four samples. The indirect antiglobulin tests also showed wide interlaboratory variability and were less sensitive than the direct method in four laboratories. Eleven of the 14 laboratories that expressed an opinion considered that the level of anti-D in 02/228 was appropriate to define a specified limit.Our results demonstrate the necessity of using a reference preparation to define the maximum level of anti-D in IVIG products and ensure sufficient sensitivity in haemagglutination testing methodology. On the basis of these results, members of the European Pharmacopoeia Expert Group 6B recommended revision of the appropriate monograph to include this new specification and test. The Food and Drug Administration in the USA intends to adopt the same maximal specification defined by the reference preparation and to recommend the same test for the safety of IVIG products. Preparations 02/228 and 02/226 were also established by the World Health Organization as International Reference Reagents to standardize haemagglutination testing for anti-D in normal IVIG products. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate a lyophilized anti-D immunoglobulin preparation to serve as a global standard for potency assays of anti-D immunoglobulin products. The candidate global standard, 01/572, was calibrated against the World Health Organization (WHO) International Reference Preparation (IRP) for anti-D immunoglobulin, human (68/419), along with two reserve candidate reference preparations, in an international collaborative study involving 25 laboratories in 15 countries. The United States Food and Drug Administration (US-FDA) Center for Biologics Evaluation and Research (CBER) Standard for anti-D immunoglobulin, Lot 3, was included for comparison. Most laboratories (20/25) performed AutoAnalyser methodology, competitive enzyme-linked immunoassay (EIA) and/or flow cytometry. The overall mean potency of the candidate global standard, 01/572, was 284·5 international units (IU)/ampoule, with an interlaboratory variability, expressed as a percentage geometric coefficient of variation (% gcv), of 9·7. The mean potency of the US Standard was 859·4 IU/ml with an interlaboratory variability of 9·5% gcv, excluding an outlier. The mean potencies of the reserve preparations per ampoule/vial were 110·6 IU and 106·7 IU when calibrated against the IRP, and 112·2 IU and 106·6 IU when calibrated against 01/572, respectively, with interlaboratory % gcv values of 9·6–18·3 (excluding outliers). Preparation 01/572 proved more suitable for use as a global standard than the reserve candidate preparations and was established, with an assigned potency of 285 IU/ampoule, by the WHO as the 2nd International Standard for anti-D immunoglobulin; by FDA-CBER as the Standard for anti-D immunoglobulin, Lot 4; and by the European Directorate for the Quality of Medicines (EDQM) as the 1st Biological Reference Preparation for anti-D immunoglobulin. [ABSTRACT FROM AUTHOR]

Background and Objectives The presence of anti-Rh D in intravenous immunoglobulin (IVIG) products has been claimed to be associated with adverse reactions in recipients. There is currently no regulatory specification to control the level of anti-D in IVIG products and it is unclear what this should be. Two reports of haemolysis occurring in recipients of IVIG manufactured from US plasma provided a rare opportunity to investigate whether high anti-D levels could have induced the haemolysis. Materials and Methods We developed a direct microtitre plate haemagglutination method suitable for screening IVIG products and starting plasma pools for haemagglutinating activity. Results Of 101 batches of IVIG tested, six were found to contain specific anti-D. Four of these batches had anti-D titres ranging from 64 to 256 (including the two batches each associated with a report of haemolysis) and could be linked, in each case, to a starting plasma pool also positive for anti-D. Conclusions Our results show that IVIG products can contain appreciable anti-D levels. To avoid potential problems in recipients, we propose an anti-D titre of 8 as the maximum permissible limit of anti-D in IVIG products for batch acceptance and release. The availability of a reference preparation is essential for control of this proposed requirement. [ABSTRACT FROM AUTHOR]

Summary. The development of monoclonal immunoglobulin G (IgG) anti-D for prophylaxis necessitates estimation of their potency in terms of their red cell-binding ability, but it is unclear which quantification methodology is most suitable for this. The aim of this study was to assess 50 monoclonal anti-D from the 4th International Workshop for quantitative and qualitative binding to red cells in a competitive enzyme-linked immunoassay (EIA) in which varying amounts of monoclonal antibodies (MoAbs) and a constant amount of biotinylated monoclonal anti-D (BRAD-5) compete for red cell binding. The potencies of the MoAb were estimated against the International Reference Preparation (IRP) for anti-D Ig. Two MoAbs as supplied were insufficiently inhibitory of biotinylated BRAD-5 binding to be quantified; the potencies of the remainder ranged from 4 to 343 IU mL-1 and included 11 MoAbs showing dose–responses that were nonparallel to those of other MoAb and the IRP. Estimation of the concentration of antibody in the supernatants by radial immunodiffusion ranged from 0·5 to 61 µg mL-1 , giving specific activities of <1–24 IU µg-1 . The results show that competitive EIA is suitable for quantitating most monoclonal anti-D for development and quality control purposes, regardless of their D epitope reactivity. [ABSTRACT FROM AUTHOR]

Abstract We examined post-fire responses of two sympatric Australian rodents, Pseudomys gracilicaudatus and Rattus lutreolus, as coastal wet heath regenerated following two high intensity wildfires. Pseudomys gracilicaudatus, an early seral-stage species, recolonized an area burnt in August 1974 after one year, but took only 3 months to recolonize another area following a wildfire in October 1994. Rattus lutreolus, a late seral-stage specialist, took approximately 3.6 years to recolonize following wildfire in August 1974, but had recolonized after only 4 months following wildfire in October 1994. We suggest that this apparent anomaly is associated with the rate of recovery of vegetation density. When the relative abundance of each species was plotted as a function of vegetation density, the trajectories following the two wildfires were concordant. An implicit relationship exists between time since wildfire and vegetation density. We make this relationship explicit by quantifying cover requirements for each species, and show that it is the resource continuum borne of regenerating vegetation (rather than time per se) that is important in determining the timing of small mammal successional sequences. [ABSTRACT FROM AUTHOR]

Summary Trypanosomiasis control increasingly involves financial input from livestock owners and their active participation. If control is carried out on smaller scales than in the past, methods such as aerial and ground spraying and sterile insect techniques will have reduced application. There will be increased reliance on trypanocidal drugs, and bait methods of tsetse control – where flies are attracted to point sources and killed. If drug resistance develops, cheap and simple bait methods offer the only means of disease control that might be applied, and paid for, by stockowners themselves. The methods have been effective in some circumstances, but not in others, and it is important to understand the reasons for the successes and the failures. Analysis is presented of the results of two Tanzanian tsetse control campaigns involving the use of insecticide-treated cattle. Between 1991, &, 1996, following the introduction of widespread dipping in the Kagera Region, trypanosomiasis declined from > 19 000 cases to < 2400 and deaths from > 1000 to 29. On four ranches in the region, tsetse have been almost eliminated and trypanosomiasis prophylaxis is no longer used. Similarly aggressive use of pyrethroids on Mkwaja Ranch in Tanga Region has not had such dramatic effects. Tsetse and trypanosomiasis are still common, despite high levels of prophylaxis and the deployment of ≈ 200 odour-baited targets. The difference in the results is attributed to a combination of the much smaller area covered by treated animals at Mkwaja, a greater susceptibility to re-invasion and a more suitable habitat for the flies. A better understanding of the dynamics of the use of insecticide-treated cattle is needed before we can predict confidently the outcome of particular control operations. [ABSTRACT FROM AUTHOR]

Patterns of habitat use by Pseudomys novaehollandiae and Mus domesticus were investigated on a 6.8 ha area of coastal heathland, almost five years after it last burned in Myall Lakes National Park. One hundred and fifty-one trap stations were positioned on 17 traplines across a mosaic of interlocking macrohabitats. This pattern was a consequence of the site's topography and to a lesser extent fire history. Multivariate statistical procedures were employed to identify those microhabitat parameters that contribute to both individual species' habitat use and the partitioning of habitat to reduce competition for space. Trapping results show P. novaehollandiae to be almost three times as abundant as M. domesticus at this time although M. domesticus doesshow strong regional, and hence local, fluctuations in abundance over time. Both species exhibit habitat selection (P < 0.05) with individuals preferring dry, tall closed heath and open heathland habitats. Immature P. novaehollandiae (< 15 g) were found mostly in short densewet heath and may have been dispersing. Species exhibit high between-habitat overlap using Pianka's formula (0.88). This overlap is substantially reduced within macrohabitats (0.28), when trap stations are considered as resource states, suggesting a considerable degree of microhabitat separation at the trap station level. Discriminant function and multiple regression analyses identify microhabitat selection that is not strongly focused, suggesting both species to be spatial generalists. Elevation was selected as the most significant variable in these analyses and represents a soil moisture gradient that determines changes in the floristic and structural components of the biotic environment. No single habitat variable was found to explain within-habitat separation convincingly, however, when a factor analysis of habitat variables was used to produce a reduced three-dimensional factor space the outcome was marked. The 95 % confidence envelopes for the dis [ABSTRACT FROM AUTHOR]

This paper examines helper T-cell responses and antibody titres and isotypes following immunization with a peptide antigen in association with three different adjuvants. B10.A mice were primed with pigeon cytochrome c fragment 81-104 in association with the adjuvants complete Freund's adjuvant (CFA), incomplete Freund's adjuvant (IFA) and alum. Strong antibody responses, dominated by IgG1, were observed upon priming with CFA and IFA. In contrast, priming with alum induced a weak antibody response with little or no detectable antigen-specific IgG1. These differences did not correlate with differences in T-cell priming, as immunization with peptide in association with all three adjuvants induced comparable T-cell proliferative responses and frequencies of antigen-specific cells. In addition, no significant differences in iiiterleukin-2 (IL-2), interferon-gamma (IFN-γ) and IL-4 production could be found, suggesting that the adjuvants did not differentially affect Th1 and Th2 cells. [ABSTRACT FROM AUTHOR]

Lectins can be used to detect changes in cell-surface glycosylation. In this paper we examine the lectin-binding characteristics of murine T cells as measured by flow cytometry. A large panel of labelled lectins was used to stain naive, activated and resting murine T cells. Some lectins did not detectably bind any T cells, some bound to all T cells and some bound to only a subset of splenic T cells. Three lectins which preferentially bind to previously activated T cells were identified: Bandeiraea simplicifolia BS-I, Bauhinia purpurea and Lycopersicon esculentum. In addition, two lectins were found to bind preferentially to activated T cells; Glycine max and Triticum vulgaris. Finally, no differences were found in the ability of a large panel of lectins to bind to Th1 and Th2 clones. Lectin binding may be a powerful tool for distinguishing naive, activated and memory T cells. [ABSTRACT FROM AUTHOR]

Turbitt et al. [1] and Ashken and Thompson [2] raise two valid points regarding the current shape of regional anaesthesia teaching and training. Regional Anaesthesia UK (RA-UK) feels all anaesthetists should be able to perform basic blocks as a requirement for achieving a CCT in anaesthesia. Regional Anaesthesia-UK now highlights the variation offered by courses through the RA-UK course approval process. [Extracted from the article]

A letter to the editor commenting on the article "A Randomised Controlled Trial of Intrathecal Blockade Versus Peripheral Nerve Blockade for Day-Case Knee Arthroscopy," by researcher A.L. Ambrosoli and colleagues is presented