Real-world use of thrombopoietin receptor agonists for the management of immune thrombocytopenia in adult patients in the United Kingdom: Results from the TRAIT study.

Few studies have reported the real-world use of both romiplostim and eltrombopag in immune thrombocytopenia (ITP). TRAIT was a retrospective observational study aimed to evaluate the platelet responses and adverse effects associated with the use of these thrombopoietin receptor agonists (TPO-RAs) in adult patients with ITP in the United Kingdom. Of 267 patients (median age at diagnosis, 48 years) with ITP (primary ITP [n = 218], secondary ITP [n = 49]) included in the study, 112 (42%) received eltrombopag and 155 (58%) received romiplostim as the first prescribed TPO-RA. A platelet count ≥30 × 109/L was achieved in 89% of patients with the first TPO-RA treatments, while 68% achieved a platelet count ≥100 × 109/L. Treatment-free response (TFR; platelet count ≥30 × 109/L, 3 months after discontinuing treatment) was achieved by 18% of the total patients. Overall, 61 patients (23%) switched TPO-RAs, most of whom achieved platelet counts ≥30 × 109/L with the second TPO-RA (23/25 who switched from eltrombopag to romiplostim [92%]; 28/36 who switched from romiplostim to eltrombopag [78%]). TFR was associated with secondary ITP, early TPO-RA initiation after diagnosis, the presence of comorbidity and no prior splenectomy or treatment with steroids or mycophenolate mofetil. Both TPO-RAs had similar efficacy and safety profiles to those reported in clinical studies.

Isotopically characterised N2 O reference materials for use as community standards.

RATIONALE: Information on the isotopic composition of nitrous oxide (N2 O) at natural abundance supports the identification of its source and sink processes. In recent years, a number of mass spectrometric and laser spectroscopic techniques have been developed and are increasingly used by the research community. Advances in this active research area, however, critically depend on the availability of suitable N2 O isotope Reference Materials (RMs). METHODS: Within the project Metrology for Stable Isotope Reference Standards (SIRS), seven pure N2 O isotope RMs have been developed and their 15 N/14 N, 18 O/16 O, 17 O/16 O ratios and 15 N site preference (SP) have been analysed by specialised laboratories against isotope reference materials. A particular focus was on the 15 N site-specific isotopic composition, as this measurand is both highly diagnostic for source appointment and challenging to analyse and link to existing scales. RESULTS: The established N2 O isotope RMs offer a wide spread in delta (δ) values: δ15 N: 0 to +104‰, δ18 O: +39 to +155‰, and δ15 NSP : -4 to +20‰. Conversion and uncertainty propagation of δ15 N and δ18 O to the Air-N2 and VSMOW scales, respectively, provides robust estimates for δ15 N(N2 O) and δ18 O(N2 O), with overall uncertainties of about 0.05‰ and 0.15‰, respectively. For δ15 NSP , an offset of >1.5‰ compared with earlier calibration approaches was detected, which should be revisited in the future. CONCLUSIONS: A set of seven N2 O isotope RMs anchored to the international isotope-ratio scales was developed that will promote the implementation of the recommended two-point calibration approach. Particularly, the availability of δ17 O data for N2 O RMs is expected to improve data quality/correction algorithms with respect to δ15 NSP and δ15 N analysis by mass spectrometry. We anticipate that the N2 O isotope RMs will enhance compatibility between laboratories and accelerate research progress in this emerging field.

Primary mesenchymal stromal cells in co-culture with leukaemic HL-60 cells are sensitised to cytarabine-induced genotoxicity, while leukaemic cells are protected.

Tumour microenvironments are hallmarked in many cancer types. In haematological malignancies, bone marrow (BM) mesenchymal stromal cells (MSC) protect malignant cells from drug-induced cytotoxicity. However, less is known about malignant impact on supportive stroma. Notably, it is unknown whether these interactions alter long-term genotoxic damage in either direction. The nucleoside analogue cytarabine (ara-C), common in haematological therapies, remains the most effective agent for acute myeloid leukaemia, yet one-third of patients develop resistance. This study aimed to evaluate the bidirectional effect of MSC and malignant cell co-culture on ara-C genotoxicity modulation. Primary MSC, isolated from patient BM aspirates for haematological investigations, and malignant haematopoietic cells (leukaemic HL-60) were co-cultured using trans-well inserts, prior to treatment with physiological dose ara-C. Co-culture genotoxic effects were assessed by micronucleus and alkaline comet assays. Patient BM cells from chemotherapy-treated patients had reduced ex vivo survival (P = 0.0049) and increased genotoxicity (P = 0.3172) than untreated patients. It was shown for the first time that HL-60 were protected by MSC from ara-C-induced genotoxicity, with reduced MN incidence in co-culture as compared to mono-culture (P = 0.0068). Comet tail intensity also significantly increased in ara-C-treated MSC with HL-60 influence (P = 0.0308). MSC sensitisation to ara-C genotoxicity was also demonstrated following co-culture with HL60 (P = 0.0116), which showed significantly greater sensitisation when MSC-HL-60 co-cultures were exposed to ara-C (P = 0.0409). This study shows for the first time that malignant HSC and MSC bidirectionally modulate genotoxicity, providing grounding for future research identifying mechanisms of altered genotoxicity in leukaemic microenvironments. MSC retain long-term genotoxic and functional damage following chemotherapy exposure. Understanding the interactions perpetuating such damage may inform modifications to reduce therapy-related complications, such as secondary malignancies and BM failure.

Development of a structured process for fair allocation of critical care resources in the setting of insufficient capacity: a discussion paper.

Early in the COVID-19 pandemic there was widespread concern that healthcare systems would be overwhelmed, and specifically, that there would be insufficient critical care capacity in terms of beds, ventilators or staff to care for patients. In the UK, this was avoided by a threefold approach involving widespread, rapid expansion of critical care capacity, reduction of healthcare demand from non-COVID-19 sources by temporarily pausing much of normal healthcare delivery, and by governmental and societal responses that reduced demand through national lockdown. Despite high-level documents designed to help manage limited critical care capacity, none provided sufficient operational direction to enable use at the bedside in situations requiring triage. We present and describe the development of a structured process for fair allocation of critical care resources in the setting of insufficient capacity. The document combines a wide variety of factors known to impact on outcome from critical illness, integrated with broad-based clinical judgement to enable structured, explicit, transparent decision-making founded on robust ethical principles. It aims to improve communication and allocate resources fairly, while avoiding triage decisions based on a single disease, comorbidity, patient age or degree of frailty. It is designed to support and document decision-making. The document has not been needed to date, nor adopted as hospital policy. However, as the pandemic evolves, the resumption of necessary non-COVID-19 healthcare and economic activity mean capacity issues and the potential need for triage may yet return. The document is presented as a starting point for stakeholder feedback and discussion.

Opening Opportunities for High-Resolution Isotope Analysis - Quantification of δ15NNO3 and δ18ONO3 in Diffusive Equilibrium in Thin-Film Passive Samplers.

The fate of nitrate transported across groundwater-surface water interfaces has been intensively studied in recent decades. The interfaces between aquifers and rivers or lakes have been identified as biogeochemical hotspots with steep redox gradients. However, a detailed understanding of the spatial heterogeneity and potential temporal variability of these hotspots, and the consequences for nitrogen processing, is still hindered by a paucity of adequate measurement techniques. A novel methodology is presented here, using Diffusive Equilibrium in Thin-film (DET) gels as high-spatial-resolution passive-samplers of δ15NNO3 and δ18ONO3 to investigate nitrogen cycling. Fractionation of δ15NNO3 and δ18ONO3 during diffusion of nitrate through the DET gel was determined using varying equilibrium times and nitrate concentrations. This demonstrated that nitrate isotopes of δ15NNO3 and δ18ONO3 do not fractionate when sampled with a DET gel. δ15NNO3 values from the DET gels ranged between 2.3 ± 0.2 and 2.7 ± 0.3‰ for a NO3- stock solution value of 2.7 ± 0.4‰, and δ18ONO3 values ranged between 18.3 ± 1.0 and 21.5 ± 0.8‰ for a NO3- stock solution of 19.7 ± 0.9‰. Nitrate recovery and isotope values were independent of equilibrium time and nitrate concentration. Additionally, an in situ study showed that nitrate concentration and isotopes provide unique, high-resolution data that enable improved understanding of nitrogen cycling in freshwater sediments.

Hydrogeological Controls on Regional-Scale Indirect Nitrous Oxide Emission Factors for Rivers.

Indirect nitrous oxide (N2O) emissions from rivers are currently derived using poorly constrained default IPCC emission factors (EF5r) which yield unreliable flux estimates. Here, we demonstrate how hydrogeological conditions can be used to develop more refined regional-scale EF5r estimates required for compiling accurate national greenhouse gas inventories. Focusing on three UK river catchments with contrasting bedrock and superficial geologies, N2O and nitrate (NO3-) concentrations were analyzed in 651 river water samples collected from 2011 to 2013. Unconfined Cretaceous Chalk bedrock regions yielded the highest median N2O-N concentration (3.0 µg L-1), EF5r (0.00036), and N2O-N flux (10.8 kg ha-1 a-1). Conversely, regions of bedrock confined by glacial deposits yielded significantly lower median N2O-N concentration (0.8 µg L-1), EF5r (0.00016), and N2O-N flux (2.6 kg ha-1 a-1), regardless of bedrock type. Bedrock permeability is an important control in regions where groundwater is unconfined, with a high N2O yield from high permeability chalk contrasting with significantly lower median N2O-N concentration (0.7 µg L-1), EF5r (0.00020), and N2O-N flux (2.0 kg ha-1 a-1) on lower permeability unconfined Jurassic mudstone. The evidence presented here demonstrates EF5r can be differentiated by hydrogeological conditions and thus provide a valuable proxy for generating improved regional-scale N2O emission estimates.

Isotopic signals of summer denitrification in a northern hardwood forested catchment.

Despite decades of measurements, the nitrogen balance of temperate forest catchments remains poorly understood. Atmospheric nitrogen deposition often greatly exceeds streamwater nitrogen losses; the fate of the remaining nitrogen is highly uncertain. Gaseous losses of nitrogen to denitrification are especially poorly documented and are often ignored. Here, we provide isotopic evidence (δ(15)NNO3 and δ(18)ONO3) from shallow groundwater at the Hubbard Brook Experimental Forest indicating extensive denitrification during midsummer, when transient, perched patches of saturation developed in hillslopes, with poor hydrological connectivity to the stream, while streamwater showed no isotopic evidence of denitrification. During small rain events, precipitation directly contributed up to 34% of streamwater nitrate, which was otherwise produced by nitrification. Together, these measurements reveal the importance of denitrification in hydrologically disconnected patches of shallow groundwater during midsummer as largely overlooked control points for nitrogen loss from temperate forest catchments.

'You're kind of left to your own devices': a qualitative focus group study of patients with breast, prostate or blood cancer at a hospital in the South West of England, exploring their engagement with exercise and physical activity during cancer treatment and in the months following standard care.

OBJECTIVES: The aim of this study was to explore the experiences of patients with breast, prostate or blood cancer, regarding their (1) engagement with exercise and physical activity during treatment and in the months following standard care, and (2) the meanings attached to these lifestyle behaviours. DESIGN: A qualitative study using focus groups. The groups were audio recorded, transcribed and analysed using Framework analysis. SETTING: A hospital-based cancer treatment centre in the South-West of England. PARTICIPANTS: Eighteen people who had either completed treatment or were currently on maintenance therapy for breast, prostate or blood cancer (non-Hodgkin lymphoma or Hodgkin lymphoma). RESULTS: Participants reported treatment limiting their ability to engage in exercise and physical activity. However, participants were aware of the physiological, emotional and social benefits of exercise and expressed a desire to maintain a physically active lifestyle before, during and after treatment. They noted a lack of concrete guidance and appropriate exercise classes for people with cancer and felt poorly informed about the type, intensity, duration and frequency of exercise they should be undertaking. As such, participants reported making decisions on their own, relying on their intuition and listening to their bodies to gauge whether they were doing enough exercise (or not). CONCLUSIONS: Participants were aware of the benefits of a physically active lifestyle during and following cancer treatment, but were not familiar with exercise and physical activity guidelines for people living with and beyond cancer. There is a need for healthcare professionals, academics and policy makers to determine how exercise and physical activity can be supported in clinical settings in realistic and meaningful ways accommodating individual patient circumstances.

Catchment-scale quantification of hyporheic denitrification using an isotopic and solute flux approach.

A dual-isotope and solute flux mass-balance was used to elucidate the processes that lead to attenuation of nitrogen contamination in an agriculturally impacted river. The River Wensum drains a lowland catchment with an area of 570 km² in East Anglia, eastern England. Analysis of nitrate concentration, δ¹5N(NO3) and δ¹8O(NO3) of samples from the River Wensum collected from upstream locations to the catchment outlet through all seasons and flow conditions showed a consistent pattern of increasing isotope values with decreasing nitrate concentrations downstream. δ¹5N(NO3) and δ¹8O(NO3) of catchment surface water and groundwater samples revealed a dominant influence from microbially cycled and nitrified source-nitrogen, which results in high nitrate concentrations in Chalk groundwater and upstream in the River Wensum. Denitrification of Chalk groundwater-baseflow in the hyporheic zone results in the downstream trend observed in the river. Hyporheic denitrification is estimated to remove 931 kg/day of nitrate-nitrogen by the catchment outlet, representing 31% of the potential riverine nitrate load. The use of dual-isotope and solute flux modeling at the catchment scale is a novel application to quantify denitrification within the river valley, demonstrating the importance of hyporheic zone processes in attenuating the impacts of anthropogenic contamination of hydrologic systems.

Identifying causes of poor water quality in a Polish agricultural catchment for designing effective and targeted mitigation measures.

The Gowienica Miedwianska catchment is a small agricultural catchment located in the NW of Poland draining into Lake Miedwie, on which a drinking water source for the city of Szczecin is located. The catchment is characterized by very rich soils. Subsequently, agriculture is intensive and this is thought to influence the poor water quality in the local area. Despite more than 20 years since first programmes of measures towards protection of water quality have been introduced into the catchment, these have not been produced the expected results, and the local farming community cites other sources such as poor sewage management rather that agricultural activity, as responsible for this problem. Evaluation of flow pathways in the catchment and identification of the areas responsible for the highest impact on local water quality was therefore conducted within the EU funded project Waterprotect. The aim of this study was to clarify sources of pollution precisely in space and time, in order to increase trust from stakeholders, so that targeted measures can be used effectively to improve water quality. The study included water quality monitoring, isotopic analysis and numerical flow modelling. Results showed that water quality in the catchment is spatially and temporally variable. 93% of nitrogen loadings into the Miedwie lake have been attributed to agriculture and only 7% to wastewater inputs. The local hydrology and hydrogeology play an important role in the distribution of the impacts from these inputs. As a result, three sub-catchments were identified which are differentiated by dominant pollution source, land use, and hydraulic characteristics. The highest inputs from agriculture have been identified in the most upper sub-catchment and this area have been pointed out as most suitable for implementation of agricultural best management practices towards protection of water quality at a local level.

Chemotherapy-induced mesenchymal stem cell damage in patients with hematological malignancy.

Hematopoietic recovery after high-dose chemotherapy (HDC) in the treatment of hematological diseases may be slow and/or incomplete. This is generally attributed to progressive hematopoietic stem cell failure, although defective hematopoiesis may be in part due to poor stromal function. Chemotherapy is known to damage mature bone marrow stromal cells in vitro, but the extent to which marrow mesenchymal stem cells (MSCs) are damaged by HDC in vivo is largely unknown. To address this question, the phenotype and functional properties of marrow MSCs derived from untreated and chemotherapeutically treated patients with hematological malignancy were compared. This study demonstrates a significant reduction in MSC expansion and MSC CD44 expression by MSCs derived from patients receiving HDC regimens, thus implicating potential disadvantages in the use of autologous MSCs in chemotherapeutically pretreated patients for future therapeutic strategies. The clinical importance of these HDC-induced defects we have observed could be determined through prospective randomized trials of the effects of MSC cotransplantation on hematopoietic recovery in the setting of HDC with and without hematopoietic stem cell rescue.

The experiences of cancer patients within the material hospital environment: Three ways that materiality is affective.

Improving the patient experience is widely recognised as an important goal in the delivery of high-quality healthcare. This study contributes to this goal with a particular focus on the role of the material hospital environment for patients being treated for cancer. Extending the burgeoning literature utilising materialist theoretical approaches in social science and medicine, we report on qualitative data with 18 participants who had received cancer treatment from one UK hospital. Our analysis offers a typology of ways in which the material hospital environment is affective: through patients' direct intra-actions with nonhuman materiality; through providing shared spaces within which human-human assemblages are actualised; and through being the material component of the practices of treatment. Within each process in this typology, the analysis highlights how the affective feeling states which play a critical role in patient wellbeing are in many ways contingent, fluid and context-sensitive. Amidst ambitions to improve the patient experience, these findings underline the significance of materialities of care and offer a broad explanatory typology with analytic and practical potential for healthcare staff, patient groups, architects and designers.

Adult bone marrow is a rich source of human mesenchymal 'stem' cells but umbilical cord and mobilized adult blood are not.

In postnatal life, mesenchymal stem cells (MSC) self-replicate, proliferate and differentiate into mesenchymal tissues, including bone, fat, tendon, muscle and bone marrow (BM) stroma. Possible clinical applications for MSC in stem cell transplantation have been proposed. We have evaluated the frequency, phenotype and differentiation potential of MSC in adult BM, cord blood (CB) and peripheral blood stem cell collections (PBSC). During culture, BM MSC proliferated to confluence in 10-14 d, maintaining a stable non-haemopoietic phenotype, HLA class-1+, CD29+, CD44+, CD90+, CD45-, CD34- and CD14 through subsequent passages. Using the colony forming unit fibroblasts assay, the estimated frequency of MSC in the BM nucleated cell population was 1 in 3.4 x 10(4) cells. Both adipogenic and osteogenic differentiation of BM MSC was demonstrated. In contrast, CB and PBSC mononuclear cells cultured in MSC conditions for two passages produced a population of adherent, non-confluent fibroblast-like cells with a haemopoietic phenotype, CD45+, CD14+, CD34-, CD44-, CD90- and CD29-. In paired experiments, cultured BM MSC and mature BM stroma were seeded with CB cells enriched for CD34+. Similar numbers of colony-forming units of granulocytes-macrophages were produced by MSC-based and standard stroma cultures over 10 weeks. We conclude that adult BM is a reliable source of functional cultured MSC, but CB and PBSC are not.