Implementation of a blood bank generated tube for second blood group determination: Challenges, yield, and cost.

BACKGROUND: The second blood group determination or group check sample is a process of verifying the ABO group with a second blood sample prior to transfusion. It has been used to detect errors related to wrong blood in tube (WBIT) events and reduce the risk of ABO-incompatible transfusions. To prevent the clinical team from collecting the group check sample at the same time as the first sample, a tan top tube only available from the blood bank was introduced for second blood group determinations if drawn within 24 h of the first group and screen. STUDY DESIGN AND METHODS: This is a retrospective study analyzing data from 2005 to 2020 before and after the implementation of the blood bank supplied tan top tube for group check. The number of WBIT events, transfusion delays, and health care costs were determined. RESULTS: The number of WBIT events remained unchanged throughout the time period. No delays in transfusion or procedure were reported due to the tan top tube group check. There was no increase in group O transfusions over time. In comparison to using an ethylenediaminetetraacetic acid (EDTA) tube, the tan top tube was estimated to add an extra yearly cost of $790.79 Canadian dollars. CONCLUSION: Second blood group determination using the blood bank supplied tan top tube did not increase the number of WBIT events detected but ensured an independent sample draw. A minimal incremental cost of implementing the tan top tube was noted with no delay in transfusions or procedures.

Registration errors among patients receiving blood transfusions: a national analysis from 2008 to 2017.

BACKGROUND AND OBJECTIVES: The key first step for a safe blood transfusion is patient registration for identification and linking to past medical and transfusion history. In Canada, any deviation from standard operating procedures in transfusion is an error voluntarily reportable to a national database (Transfusion Error Surveillance System [TESS]). We used this database to characterize the subset of registration-related errors impacting transfusion care, including where, when and why the errors occurred, and to identify frequent high-risk errors. MATERIALS AND METHODS: A retrospective analysis was conducted on transfusion errors reported to TESS by sentinel reporting sites relating to patient registration and patient armbands, between 2008 and 2017. Free-text comments describing the error were coded to further categorize into common error types. The number of specimens received in the transfusion laboratory was used as the denominator for rates to allow for comparison between hospital sites. RESULTS: Five hundred and fifty-four registration errors were reported from 10 hospitals, for a global error rate of 5·4/10 000 samples (median 5·0 [interquartile range 3·7-7·0]). The potential severity was high in 85·7% of errors (n = 475). The patient experienced a consequence in 10·8% of errors (n = 60), but none resulted in patient harm. Rates varied widely and differed by nature across sites. Errors most commonly occurred in outpatient clinics or procedure units (n = 160, 28·8%) and in emergency departments (n = 130, 23·5%). CONCLUSION: Registration errors affect transfusion at every step and location in the hospital and are commonly high risk. Further research into common root causes is warranted to identify preventative strategies.

Metabolic Rate Interacts with Resource Availability to Determine Individual Variation in Microhabitat Use in the Wild.

Ecological pressures such as competition can lead individuals within a population to partition resources or habitats, but the underlying intrinsic mechanisms that determine an individual's resource use are not well understood. Here we show that an individual's own energy demand and associated competitive ability influence its resource use, but only when food is more limiting. We tested whether intraspecific variation in metabolic rate leads to microhabitat partitioning among juvenile Atlantic salmon (Salmo salar) in natural streams subjected to manipulated nutrient levels and subsequent per capita food availability. We found that individual salmon from families with a higher baseline (standard) metabolic rate (which is associated with greater competitive ability) tended to occupy faster-flowing water, but only in streams with lower per capita food availability. Faster-flowing microhabitats yield more food, but high metabolic rate fish only benefited from faster growth in streams with high food levels, presumably because in low-food environments the cost of a high metabolism offsets the benefits of acquiring a productive microhabitat. The benefits of a given metabolic rate were thus context dependent. These results demonstrate that intraspecific variation in metabolic rate can interact with resource availability to determine the spatial structuring of wild populations.

Interacting with Members of the Public to Discuss the Impact of Food Choices on Climate Change-Experiences from Two UK Public Engagement Events.

Food systems contribute to up to 37% of global greenhouse gas emissions, and emissions are increasing. Since the emissions vary greatly between different foods, citizens' choices can make a big difference to climate change. Public engagement events are opportunities to communicate these complex issues: to raise awareness about the impact of citizens' own food choices on climate change and to generate support for changes in all food system activities, the food environment and food policy. This article summarises findings from our 'Take a Bite Out of Climate Change' stand at two UK outreach activities during July 2019. We collected engagement information in three main ways: (1) individuals were invited to complete a qualitative evaluation questionnaire comprising of four questions that gauged the person's interests, perceptions of food choices and attitudes towards climate change; (2) an online multiple-choice questionnaire asking about eating habits and awareness/concerns; and (3) a token drop voting activity where visitors answered the question: 'Do you consider greenhouse gases when choosing food?' Our results indicate whether or not people learnt about the environmental impacts of food (effectiveness), how likely they are to move towards a more climate-friendly diet (behavioural change), and how to gather information more effectively at this type of event.

Imaging redox activity and Fe(II) at the microbe-mineral interface during Fe(III) reduction.

Dissimilatory iron-reducing bacteria (DIRB) play an important role in controlling the redox chemistry of Fe and other transition metals and radionuclides in the environment. During bacterial iron reduction, electrons are transferred from the outer membrane to poorly soluble Fe(III) minerals, although the precise physiological mechanisms and local impact on minerals of these redox processes remain unclear. The aim of this work was to use a range of microscopic techniques to examine the local environment of Geobacter sulfurreducens grown on thin films of Fe(III)-bearing minerals, to provide insight into spatial patterns of Fe(III) reduction and electron transfer. Confocal fluorescence microscopy showed that sparse biofilms formed on the mineral coatings, while the selective Fe(II) probe RhoNox-1 revealed Fe(II) patches on the minerals sometimes co-located with cells. Atomic force microscopy highlighted thin filamentous structures extending radially from the cell surface. Further analysis using fluorescent redox dyes showed redox-active, linear nanowires that formed cell to cell connections, although they were not implicated in playing a dominant role in direct electron transfer to the Fe(III) minerals. Overall this paper provides new methods and insights on studying Fe(III) reduction and other redox transformations in situ.

NanoSIMS imaging of extracellular electron transport processes during microbial iron(III) reduction.

Microbial iron(III) reduction can have a profound effect on the fate of contaminants in natural and engineered environments. Different mechanisms of extracellular electron transport are used by Geobacter and Shewanella spp. to reduce insoluble Fe(III) minerals. Here we prepared a thin film of iron(III)-(oxyhydr)oxide doped with arsenic, and allowed the mineral coating to be colonised by Geobacter sulfurreducens or Shewanella ANA3 labelled with 13C from organic electron donors. This preserved the spatial relationship between metabolically active Fe(III)-reducing bacteria and the iron(III)-(oxyhydr)oxide that they were respiring. NanoSIMS imaging showed cells of G. sulfurreducens were co-located with the iron(III)-(oxyhydr)oxide surface and were significantly more 13C-enriched compared to cells located away from the mineral, consistent with Geobacter species requiring direct contact with an extracellular electron acceptor to support growth. There was no such intimate relationship between 13C-enriched S. ANA3 and the iron(III)-(oxyhydr)oxide surface, consistent with Shewanella species being able to reduce Fe(III) indirectly using a secreted endogenous mediator. Some differences were observed in the amount of As relative to Fe in the local environment of G. sulfurreducens compared to the bulk mineral, highlighting the usefulness of this type of analysis for probing interactions between microbial cells and Fe-trace metal distributions in biogeochemical experiments.

Sample collection and sample handling errors submitted to the transfusion error surveillance system, 2006 to 2015.

BACKGROUND: In Canada, transfusion-related errors are voluntarily reported to a tracking system with the goal to systematically improve transfusion safety. This report provides an analysis of sample collection (SC) and sample handling (SH) errors from this national error-tracking system. STUDY DESIGN AND METHODS: Errors from 2006 to 2015 from 23 participating sites were extracted. A survey was conducted to obtain information regarding institutional policies. Samples received in the blood bank were used to calculate rates. "Wrong blood in tube" (WBIT) errors are blood taken from wrong patient and labeled with intended patient's information, or blood taken from intended patient but labeled with another patient's information. RESULTS: A total of 42,363 SC and 14,666 SH errors were reported. Predefined low-severity (low potential for harm) and high-severity errors (potential for fatal outcomes) increased from 2006 to 2015 (low SC, SH: 13-27, 3-12 per 1000; high SC, SH: 1.9-3.7, 0.5-2.0 per 1000). The WBIT rate decreased from 12 to 5.8 per 10,000 between 2006 and 2015 (p < 0.0001). The overall WBIT rate was 6.2 per 10,000, with variability by site (median, 0.3 per 10,000; range, 0-17 per 10,000). Sites with error detection mechanisms, such as regrouping second sample requirements, had lower error rates than sites that did not (SC, SH: 12, 1 per 1000 samples vs. 17, 3 per 1000 samples; p < 0.0001). CONCLUSION: WBIT rates decreased significantly. Low-severity error rates are climbing likely due to increased ascertainment and reporting. Prevention studies are necessary to inform changes to blood transfusion standards to eliminate these errors.

Nutrients from salmon parents alter selection pressures on their offspring.

Organisms can modify their surrounding environment, but whether these changes are large enough to feed back and alter their evolutionary trajectories is not well understood, particularly in wild populations. Here we show that nutrient pulses from decomposing Atlantic salmon (Salmo salar) parents alter selection pressures on their offspring with important consequences for their phenotypic and genetic diversity. We found a strong survival advantage to larger eggs and faster juvenile metabolic rates in streams lacking carcasses but not in streams containing this parental nutrient input. Differences in selection intensities led to significant phenotypic divergence in these two traits among stream types. Stronger selection in streams with low parental nutrient input also decreased the number of surviving families compared to streams with high parental nutrient levels. Observed effects of parent-derived nutrients on selection pressures provide experimental evidence for key components of eco-evolutionary feedbacks in wild populations.

Transparent soil microcosms allow 3D spatial quantification of soil microbiological processes in vivo.

The recently developed transparent soil consists of particles of Nafion, a polymer with a low refractive index (RI), which is prepared by milling and chemical treatment for use as a soil analog. After the addition of a RI-matched solution, confocal imaging can be carried out in vivo and without destructive sampling. In a previous study, we showed that the new substrate provides a good approximation of plant growth conditions found in natural soils. In this paper, we present further development of the techniques for detailed quantitative analysis of images of root-microbe interactions in situ. Using this system it was possible for the first time to analyze bacterial distribution along the roots and in the bulk substrate in vivo. These findings indicate that the coupling of transparent soil with light microscopy is an important advance toward the discovery of the mechanisms of microbial colonisation of the rhizosphere.

Hospital-based transfusion error tracking from 2005 to 2010: identifying the key errors threatening patient transfusion safety.

BACKGROUND: This report provides a comprehensive analysis of transfusion errors occurring at a large teaching hospital and aims to determine key errors that are threatening transfusion safety, despite implementation of safety measures. STUDY DESIGN AND METHODS: Errors were prospectively identified from 2005 to 2010. Error data were coded on a secure online database called the Transfusion Error Surveillance System. Errors were defined as any deviation from established standard operating procedures. Errors were identified by clinical and laboratory staff. Denominator data for volume of activity were used to calculate rates. RESULTS: A total of 15,134 errors were reported with a median number of 215 errors per month (range, 85-334). Overall, 9083 (60%) errors occurred on the transfusion service and 6051 (40%) on the clinical services. In total, 23 errors resulted in patient harm: 21 of these errors occurred on the clinical services and two in the transfusion service. Of the 23 harm events, 21 involved inappropriate use of blood. Errors with no harm were 657 times more common than events that caused harm. The most common high-severity clinical errors were sample labeling (37.5%) and inappropriate ordering of blood (28.8%). The most common high-severity error in the transfusion service was sample accepted despite not meeting acceptance criteria (18.3%). The cost of product and component loss due to errors was $593,337. CONCLUSION: Errors occurred at every point in the transfusion process, with the greatest potential risk of patient harm resulting from inappropriate ordering of blood products and errors in sample labeling.

Light Sheet Tomography (LST) for in situ imaging of plant roots.

The production of crops capable of efficient nutrient use is essential for addressing the problem of global food security. The ability of a plant's root system to interact with the soil micro-environment determines how effectively it can extract water and nutrients. In order to assess this ability and develop the fast and cost effective phenotyping techniques which are needed to establish efficient root systems, in situ imaging in soil is required. To date this has not been possible due to the high density of scatterers and absorbers in soil or because other growth substrates do not sufficiently model the heterogeneity of a soil's microenvironment. We present here a new form of light sheet imaging with novel transparent soil containing refractive index matched particles. This imaging method does not rely on fluorescence, but relies solely on scattering from root material. We term this form of imaging Light Sheet Tomography (LST). We have tested LST on a range of materials and plant roots in transparent soil and gel. Due to the low density of root structures, i.e. relatively large spaces between adjacent roots, long-term monitoring of lettuce root development in situ with subsequent quantitative analysis was achieved.

Transparent soil for imaging the rhizosphere.

Understanding of soil processes is essential for addressing the global issues of food security, disease transmission and climate change. However, techniques for observing soil biology are lacking. We present a heterogeneous, porous, transparent substrate for in situ 3D imaging of living plants and root-associated microorganisms using particles of the transparent polymer, Nafion, and a solution with matching optical properties. Minerals and fluorescent dyes were adsorbed onto the Nafion particles for nutrient supply and imaging of pore size and geometry. Plant growth in transparent soil was similar to that in soil. We imaged colonization of lettuce roots by the human bacterial pathogen Escherichia coli O157:H7 showing micro-colony development. Micro-colonies may contribute to bacterial survival in soil. Transparent soil has applications in root biology, crop genetics and soil microbiology.

Comparative analysis of 3D expression patterns of transcription factor genes and digit fate maps in the developing chick wing.

Hoxd13, Tbx2, Tbx3, Sall1 and Sall3 genes are candidates for encoding antero-posterior positional values in the developing chick wing and specifying digit identity. In order to build up a detailed profile of gene expression patterns in cell lineages that give rise to each of the digits over time, we compared 3 dimensional (3D) expression patterns of these genes during wing development and related them to digit fate maps. 3D gene expression data at stages 21, 24 and 27 spanning early bud to digital plate formation, captured from in situ hybridisation whole mounts using Optical Projection Tomography (OPT) were mapped to reference wing bud models. Grafts of wing bud tissue from GFP chicken embryos were used to fate map regions of the wing bud giving rise to each digit; 3D images of the grafts were captured using OPT and mapped on to the same models. Computational analysis of the combined computerised data revealed that Tbx2 and Tbx3 are expressed in digit 3 and 4 progenitors at all stages, consistent with encoding stable antero-posterior positional values established in the early bud; Hoxd13 and Sall1 expression is more dynamic, being associated with posterior digit 3 and 4 progenitors in the early bud but later becoming associated with anterior digit 2 progenitors in the digital plate. Sox9 expression in digit condensations lies within domains of digit progenitors defined by fate mapping; digit 3 condensations express Hoxd13 and Sall1, digit 4 condensations Hoxd13, Tbx3 and to a lesser extent Tbx2. Sall3 is only transiently expressed in digit 3 progenitors at stage 24 together with Sall1 and Hoxd13; then becomes excluded from the digital plate. These dynamic patterns of expression suggest that these genes may play different roles in digit identity either together or in combination at different stages including the digit condensation stage.

Identification of genes downstream of the Shh signalling in the developing chick wing and syn-expressed with Hoxd13 using microarray and 3D computational analysis.

Sonic hedgehog (Shh) signalling by the polarizing region at the posterior margin of the chick wing bud is pivotal in patterning the digits but apart from a few key downstream genes, such as Hoxd13, which is expressed in the posterior region of the wing that gives rise to the digits, the genes that mediate the response to Shh signalling are not known. To find genes that are co-expressed with Hoxd13 in the posterior of chick wing buds and regulated in the same way, we used microarrays to compare gene expression between anterior and posterior thirds of wing buds from normal chick embryos and from polydactylous talpid³ mutant chick embryos, which have defective Shh signalling due to lack of primary cilia. We identified 1070 differentially expressed gene transcripts, which were then clustered. Two clusters contained genes predominantly expressed in posterior thirds of normal wing buds; in one cluster, genes including Hoxd13, were expressed at high levels in anterior and posterior thirds in talpid³ wing buds, in the other cluster, genes including Ptc1, were expressed at low levels in anterior and posterior thirds in talpid³ wing buds. Expression patterns of genes in these two clusters were validated in normal and talpid³ mutant wing buds by in situ hybridisation and demonstrated to be responsive to application of Shh. Expression of several genes in the Hoxd13 cluster was also shown to be responsive to manipulation of protein kinase A (PKA) activity, thus demonstrating regulation by Gli repression. Genes in the Hoxd13 cluster were then sub-clustered by computational comparison of 3D expression patterns in normal wing buds to produce syn-expression groups. Hoxd13 and Sall1 are syn-expressed in the posterior region of early chick wing buds together with 6 novel genes which are likely to be functionally related and represent secondary targets of Shh signalling. Other groups of syn-expressed genes were also identified, including a group of genes involved in vascularisation.

Integrating technologies for comparing 3D gene expression domains in the developing chick limb.

Chick embryos are good models for vertebrate development due to their accessibility and manipulability. Recent large increases in available genomic data from both whole genome sequencing and EST projects provide opportunities for identifying many new developmentally important chicken genes. Traditional methods of documenting when and where specific genes are expressed in embryos using whole amount and section in-situ hybridisation do not readily allow appreciation of 3-dimensional (3D) patterns of expression, but this can be accomplished by the recently developed microscopy technique, Optical Projection Tomography (OPT). Here we show that OPT data on the developing chick wing from different labs can be reliably integrated into a common database, that OPT is efficient in capturing 3D gene expression domains and that such domains can be meaningfully compared. Novel protocols are used to compare 3D expression domains of 7 genes known to be involved in chick wing development. This reveals previously unappreciated relationships and demonstrates the potential, using modern genomic resources, for building a large scale 3D atlas of gene expression. Such an atlas could be extended to include other types of data, such as fate maps, and the approach is also more generally applicable to embryos, organs and tissues.