A Study of Infant Sickness

Abstract Not Provided

A and B antigen levels acquired by group O donor-derived erythrocytes following ABO-non-identical transfusion or minor ABO-incompatible haematopoietic stem cell transplantation

BACKGROUND AND OBJECTIVES: ABO-incompatible haematopoietic stem cell transplantation (HSCT) presents a challenge to blood component transfusion. The aim of this study was to investigate the weak blood group A or B antigen expression by donor-derived group O red blood cells (RBC) observed following transfusion or minor ABO-incompatible HSCT. In addition, in vitro experiments were performed to elucidate possible mechanisms underlying this phenomenon.MATERIALS AND METHODS: A sensitive flow cytometry assay for the semi-quantification of RBC A/B antigen levels was used to assess patient samples and evaluate in vitro experiments.RESULTS: Analysis of blood samples from patients, originally typed as A, B and AB but recently transplanted or transfused with cells from group O donors, revealed the A antigen expression on donor-derived RBC, ranging from very low levels in non-secretor individuals to almost subgroup Ax -like profiles in group A secretors. The B antigen expression was less readily detectable. In vitro experiments, in which group O donor RBC were incubated with (i) group A/B secretor/non-secretor donor plasma or (ii) group A/B donor RBC in the absence of plasma, supported the proposed adsorption of A/B antigen-bearing glycolipids from secretor plasma but also indicated a secretor-independent mechanism for A/B antigen acquisition as well as direct cell-to-cell transfer of ABO antigens.CONCLUSION: The in vivo conversion of donor-derived blood group O RBC to ABO subgroup-like RBC after transfusion or minor ABO-incompatible HSCT raises the question of appropriate component selection. Based on these data, AB plasma should be transfused following ABO-incompatible HSCT

Perceptions and experiences of using a nipple shield among parents and staff - an ethnographic study in neonatal units

Background: Preterm infants have an immature sucking behavior and the capacity to be exclusively breastfed may be reduced for a period of weeks or months, depending on gestational age. Nipple shields have been used, not only as a device to help mothers with sore nipples, but also to facilitate the infant’s latch on to the breast. However, the benefits of using nipple shields have been debated. The aim of this study was to explore perceptions and experiences of using a nipple shield among parents and staff in neonatal units in Sweden and England. Methods: An ethnographic study was undertaken where observations and interviews were conducted in four neonatal units in Sweden and England. The data were analyzed using a thematic networks analysis. Result: The global theme was developed and named, ‘Nipple shield in a liminal time’. This comprised of two organizing themes: ‘Relational breastfeeding’ and ‘Progression’. ‘Relational breastfeeding’ was underpinned by the basic themes, ‘good enough breast’, ‘something in between’ and ‘tranquil moment’. ‘Progression’ was underpinned by the basic themes, ‘learning quicker’, ‘short-term solution’ and ‘rescue remedy’. Although breastfeeding was seen primarily as a nutritive transaction, the relational aspects of breastfeeding were of crucial importance. These two organizing themes show the tension between acknowledging the relational aspects of breastfeeding and yet facilitating or supporting the progression of breastfeeding in the period from tube feeding or cup feeding to breastfeeding. It is a liminal time as mothers and their infants are “in between” phases and the outcome, in terms of breastfeeding, is yet to be realized. Conclusion: This study demonstrates parents’ and staffs’ perceptions of the nipple shield as a short term solution to help initiation of breastfeeding but also as a barrier between the mother and infant. It is important that the mother and baby’s own particular needs are taken into account, in a person-centred way and on an ongoing basis. Furthermore, we need to emphasise the importance of the ‘relational’ whilst understanding the need for ‘progression’. Holding these in balance may be the key to appropriate use of the nipple shield

Strategies for Detecting Difference in Map Line-up Tasks

The line-up task hides a plot of real data amongst a line-up of decoys built around some plausible null hypothesis. It has been proposed as a mechanism for lending greater reliability and confidence to statistical inferences made from data graphics. The proposition is a seductive one, but whether or not line-ups guarantee consistent interpretation of statistical structure is an open question, especially when applied to representations of geo-spatial data. We build on empirical work around the extent to which statistical structure can be reliably judged in map line-ups, paying particular attention to the strategies employed when making line-up judgements. We conducted in-depth experiments with 19 graduate students equipped with a moderate background in geovisualization. The experiments consisted of a series of map line-up tasks with two map designs: choropleth maps and a centroid-dot alternative. We chose challenging tasks in the hope of exposing participants’ sensemaking activities. Through structured qualitative analysis of think-aloud protocols, we identify six sensemaking strategies and evaluate their effects in making judgements from map line-ups. We find five sensemaking strategies applicable to most visualization types, but one that seems particular to map line-up designs. We could not identify one single successful strategy, but users adopt a mix of different strategies, depending on the circumstances. We also found that choropleth maps were easier to use than centroid-dot maps

Crab cavities for linear colliders

Crab cavities have been proposed for a wide number of accelerators and interest in crab cavities has recently increased after the successful operation of a pair of crab cavities in KEK-B. In particular crab cavities are required for both the ILC and CLIC linear colliders for bunch alignment. Consideration of bunch structure and size constraints favour a 3.9 GHz superconducting, multi-cell cavity as the solution for ILC, whilst bunch structure and beam-loading considerations suggest an X-band copper travelling wave structure for CLIC. These two cavity solutions are very different in design but share complex design issues. Phase stabilisation, beam loading, wakefields and mode damping are fundamental issues for these crab cavities. Requirements and potential design solutions will be discussed for both colliders.Comment: 3 pages. To be published in proceedings of LINAC 2008, Victoria, Canad

Direct characterization of the native structure and mechanics of cyanobacterial carboxysomes

Carboxysomes are proteinaceous organelles that play essential roles in enhancing carbon fixation in cyanobacteria and some proteobacteria. These self-assembling organelles encapsulate Ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) and carbonic anhydrase using a protein shell structurally resembling an icosahedral viral capsid. The protein shell serves as a physical barrier to protect enzymes from the cytosol and a selectively permeable membrane to mediate transport of enzyme substrates and products. The structural and mechanical nature of native carboxysomes remain unclear. Here, we isolate functional β-carboxysomes from the cyanobacterium Synechococcus elongatus PCC7942 and perform the first characterization of the macromolecular architecture and inherent physical mechanics of single β-carboxysomes using electron microscopy, atomic force microscopy (AFM) and proteomics. Our results illustrate that the intact β-carboxysome comprises three structural domains, a single-layered icosahedral shell, an inner layer and paracrystalline arrays of interior Rubisco. We also observe the protein organization of the shell and partial β-carboxysomes that likely serve as the β-carboxysome assembly intermediates. Furthermore, the topography and intrinsic mechanics of functional β-carboxysomes are determined in native conditions using AFM and AFM-based nanoindentation, revealing the flexible organization and soft mechanical properties of β-carboxysomes compared to rigid viruses. Our study provides new insights into the natural characteristics of β-carboxysome organization and nanomechanics, which can be extended to diverse bacterial microcompartments and are important considerations for the design and engineering of functional carboxysomes in other organisms to supercharge photosynthesis. It offers an approach for inspecting the structural and mechanical features of synthetic metabolic organelles and protein scaffolds in bioengineering

Survival on Renal Replacement Therapy: Data from the EDTA Registry

Extensive survival data are presented from the EDTA Registry's files for patients who started renal replacement therapy in 1970-1974 compared to 1980-1984. The contribution of the different treatment modalities (haemodialysis, continuous peritoneal dialysis, and transplantation) to the survival of patients according to geographical region is also shown. Survival on renal replacement therapy, irrespective of treatment modality and of primary renal disease, was best in the 10-14-year-old patients, with 58% at 10 years and 52% at 15 years, and decreased with rising age to 28% at 10 years and 16% at 15 years in patients aged 45-54 when they commenced therapy in 1970-1974. When comparing the 0-4-year-old with the 10-14-year-old cohort of the paediatric patients, 5-year survival rates for patients starting renal replacement therapy in the early eighties declined from 85% to 70% with decreasing age. Treatment policy, as reflected by the proportion of patients on different modes of therapy, varied markedly between European regions but affected survival to a small extent only. The large population with diabetic nephropathy incurred annual mortality rates 2-3 times greater than those observed in patients with ‘standard' primary renal diseases. Haemodialysis and continuous peritoneal dialysis, although not comparable because of important differences in selection policy, yielded similar survival rates. Patient and graft survival rates have improved markedly when comparing patients starting renal replacement therapy in the early seventies with the eighties; particularly for cadaveric transplantation. Patient survival after second grafting was similar to that after first grafting, with 83% at 5 years after second cadaveric grafting in the 15-44-year-old cohort, vs 85% after first cadaver transplantation in 1980-1984. Second cadaveric graft survival was superior to average first-graft survival for those recipients whose first graft had been functioning for more than 1 year. However, second-graft survival in rapid rejectors of a first graft as well as third cadaveric graft survival were curtailed by the large number of early losses, with only 52% of third grafts functioning at 1 year. For living related donor transplantation, parents were mostly used in children whilst identical siblings predominated in adults older than 45. In the early eighties, patient survival was 92% at 5 years for recipients younger than 15, 87% for the 15-45 year old cohort and 72% for those aged 45 or older. From the overall survival rates on renal replacement therapy obtained at 5 years in the early eighties, it appears safe to predict that at least 65% of young adults and 25% of patients aged 55-64 will be surviving at 10 years after starting therap

Demography of Dialysis and Transplantation in Europe, 1984: Report from the European Dialysis and Transplant Association Registry

The demography of treatment of children by renal replacement therapy in Europe is presented based on returns of individual patient questionnaires to the EDTA Registry up until the close of 1984. Patient questionnaires for 1984 were completed by all centres which defined themselves as special paediatric units. A total of 4983 patients have been reported to the Registry up until 31 December 1984 as having commenced renal replacement therapy under the age of 15. Of these, 1570 were known to be alive on a defined form of treatment at the end of 1984 and still under the age of 15. The numbers of these patients kept alive by different forms of treatment in individual countries are presented. The stock of patients aged under 15 at the end of 1984 exceeded 30 per million child population in Belgium, France, Iceland and Luxembourg. The highest age specific acceptance rates for children onto renal replacement therapy during 1984 were noted in those aged between 10 and 14 at first treatment. Age specific acceptance rates for children varied greatly between individual countries, and 18 countries reported no new patients under the age of 5 during 1984. Transplant activity in paediatric patients during 1984 has been analysed and results on regrafting presented. Proportional distribution of primary renal diseases amongst children commencing therapy in 1984 is shown according to age at start of treatment. Haemolytic uraemic syndrome was reported as the cause of end-stage renal failure in 12.0% of children commencing treatment under the age of 5, and 12.3% of children between 5 and 9. Finally, information on cause of death in paediatric patients dying during 1984 is presented, and shows cardiovascular disease was the leading cause of mortalit