The CEP5 Peptide Promotes Abiotic Stress Tolerance, As Revealed by Quantitative Proteomics, and Attenuates the AUX/IAA Equilibrium in Arabidopsis

Peptides derived from non-functional precursors play important roles in various developmental processes, but also in (a)biotic stress signaling. Our (phospho)proteome-wide analyses of C-TERMINALLY ENCODED PEPTIDE 5 (CEP5)-mediated changes revealed an impact on abiotic stress-related processes. Drought has a dramatic impact on plant growth, development and reproduction, and the plant hormone auxin plays a role in drought responses. Our genetic, physiological, biochemical, and pharmacological results demonstrated that CEP5-mediated signaling is relevant for osmotic and drought stress tolerance in Arabidopsis, and that CEP5 specifically counteracts auxin effects. Specifically, we found that CEP5 signaling stabilizes AUX/IAA transcriptional repressors, suggesting the existence of a novel peptide-dependent control mechanism that tunes auxin signaling. These observations align with the recently described role of AUX/IAAs in stress tolerance and provide a novel role for CEP5 in osmotic and drought stress tolerance.

Autoantigens PLA2R and THSD7A in membranous nephropathy share a common epitope motif in the N-terminal domain

Patients with membranous nephropathy have autoantibodies against PLA2R (up to 80%), or THSD7A (up to 2%). We previously described the immunodominant epitope within PLA2R but epitopes in THSD7A are still unknown. To find anti-THSD7A sera for this study, we screened 1843 sera from biopsy-proven MN patients by ELISA and identified 22 sera as anti-THSD7A positive representing 1.2% of MN cases. Anti-THSD7A positive sera were further characterized by western blotting and slot blotting on THSD7A protein fragments and peptides. Real time interaction analyses and antibodies off-rate could be reliably determined using bio-layer interferometry. A signature motif in the N-terminal domain of THSD7A (T28mer) with sequence homology to the major PLA2R epitope (P28mer) was identified. B-cell epitope prediction analysis and homology modelling revealed this sequence to be antigenic and surface available suggesting it is accessible for the antibody to bind. All ten selected sera bound to the T28mer confirming this sequence as a dominant epitope in THSD7A. Reactivity to this sequence was lost following kallikrein protease cleavage within the predicted epitope. Importantly, cross-reactivity of both PLA2R and THSD7A autoantibodies was observed at the peptide but not the protein level. We propose that this common motif shared by both autoantigens could be an epitope involved in the initial B-cell triggering event in MN.

CEP5 and XIP1/CEPR1 regulate lateral root initiation in Arabidopsis

Roots explore the soil for water and nutrients through the continuous production of lateral roots. Lateral roots are formed at regular distances in a steadily elongating organ, but how future sites for lateral root formation become established is not yet understood. Here, we identified C-TERMINALLY ENCODED PEPTIDE 5 (CEP5) as a novel, auxin-repressed and phloem pole-expressed signal assisting in the formation of lateral roots. In addition, based on genetic and expression data, we found evidence for the involvement of its proposed receptor, XYLEM INTERMIXED WITH PHLOEM 1 (XIP1)/CEP RECEPTOR 1 (CEPR1), during the process of lateral root initiation. In conclusion, we report here on the existence of a peptide ligand-receptor kinase interaction that impacts lateral root initiation. Our results represent an important step towards the understanding of the cellular communication implicated in the early phases of lateral root formation.

Road traffic injuries to children during the school commute in Hyderabad, India: cross-sectional survey

BACKGROUND

India is motorising rapidly. With increasing motorisation, road traffic injuries are predicted to increase. A third of a billion children travel to school every day in India, but little is known about children's safety during the school commute. We investigated road traffic injury to children during school journeys.

METHODS

We conducted a cross-sectional survey in Hyderabad using a two-stage stratified cluster sampling design. We used school travel questionnaires to record any road injury in the past 12 months that resulted in at least 1 day of school missed or required treatment by a doctor or nurse. We estimated the prevalence of road injury by usual mode of travel and distance to school.

RESULTS

The total sample was 5842 children, of whom 5789 (99.1%) children answered the question on road injury. The overall prevalence of self-reported road injury in the last 12 months during school journeys was 17% (95% CI 12.9% to 21.7%). A higher proportion of boys (25%) reported a road injury than girls (11%). There was a strong association between road injury, travel mode and distance to school. Children who cycled to school were more likely to be injured compared with children who walked (OR 1.5; 95% CI 1.2 to 2.0). Travel by school bus was safer than walking (OR 0.5; 95% CI 0.3 to 0.9).

CONCLUSIONS

A sixth of the children reported a road traffic injury in the past 12 months during school journeys in Hyderabad. Injury prevention interventions should focus on making walking and cycling safer for children.

Lateral Root Inducible System in Arabidopsis and Maize

Lateral root development contributes significantly to the root system, and hence is crucial for plant growth. The study of lateral root initiation is however tedious, because it occurs only in a few cells inside the root and in an unpredictable manner. To circumvent this problem, a Lateral Root Inducible System (LRIS) has been developed. By treating seedlings consecutively with an auxin transport inhibitor and a synthetic auxin, highly controlled lateral root initiation occurs synchronously in the primary root, allowing abundant sampling of a desired developmental stage. The LRIS has first been developed for Arabidopsis thaliana, but can be applied to other plants as well. Accordingly, it has been adapted for use in maize (Zea mays). A detailed overview of the different steps of the LRIS in both plants is given. The combination of this system with comparative transcriptomics made it possible to identify functional homologs of Arabidopsis lateral root initiation genes in other species as illustrated here for the CYCLIN B1;1 (CYCB1;1) cell cycle gene in maize. Finally, the principles that need to be taken into account when an LRIS is developed for other plant species are discussed.

Prenatal therapy in transient abnormal myelopoiesis: a systematic review

OBJECTIVE

To systematically review current evidence regarding prenatal diagnosis and management of transient abnormal myelopoiesis (TAM) in fetuses with trisomy 21. A novel case of GATA1-positive TAM, in which following serial in utero blood transfusion clinical improvement and postnatal remission were observed, is included.

SEARCH STRATEGY AND DATA COLLECTION

A systematic search of electronic databases (inception to October 2014) and reference lists, hand-searching of journals and expert contact. All confirmed cases of prenatal TAM were included for analysis. Data on study characteristics, design and quality were obtained.

RESULTS

Of 73 potentially relevant citations identified, 22 studies were included, describing 39 fetuses. All studies included comprised single case or small cohort studies; overall quality was 'very low'. Fetal/neonatal outcome was poor; 12 stillbirths (30.8%), 4 neonatal deaths (10.2%) and 7 infant deaths (17.9%). In two cases, the pregnancy was terminated (5.1%). TAM was primarily detected in the third trimester (79.4%), and in 14 a retrospective diagnosis was made postpartum. Ultrasound features indicative of TAM included hepatomegaly±splenomegaly (79.5%), hydrops fetalis (30.8%), pericardial effusion (23.1%) and aberrant liquor volume (15.4%). When performed, liver function tests were abnormal in 91.6% of cases.

CONCLUSIONS

Prenatal TAM presents a challenging diagnosis, and prognosis is poor, with consistently high mortality. A low threshold to measure haematological and biochemical markers is advised when clinical features typical of TAM are detected in the context of trisomy 21. Larger prospective studies are warranted to accurately ascertain the role of GATA1 analysis and potential value of prenatal therapy.

Development and validation of a self-administered questionnaire to estimate the distance and mode of children's travel to school in urban India

Background

Although some 300 million Indian children travel to school every day, little is known about how they get there. This information is important for transport planners and public health authorities. This paper presents the development of a self-administered questionnaire and examines its reliability and validity in estimating distance and mode of travel to school in a low resource urban setting.

Methods

We developed a questionnaire on children’s travel to school. We assessed test re-test reliability by repeating the questionnaire one week later (n = 61). The questionnaire was improved and re-tested (n = 68). We examined the convergent validity of distance estimates by comparing estimates based on the nearest landmark to children’s homes with a ‘gold standard’ based on one-to-one interviews with children using detailed maps (n = 50).

Results

Most questions showed fair to almost perfect agreement. Questions on usual mode of travel (κ 0.73- 0.84) and road injury (κ 0.61- 0.72) were found to be more reliable than those on parental permissions (κ 0.18- 0.30), perception of safety (κ 0.00- 0.54), and physical activity (κ -0.01- 0.07). The distance estimated by the nearest landmark method was not significantly different than the in-depth method for walking , 52 m [95 % CI -32 m to 135 m], 10 % of the mean difference, and for walking and cycling combined, 65 m [95 % CI -30 m to 159 m], 11 % of the mean difference. For children who used motorized transport (excluding private school bus), the nearest landmark method under-estimated distance by an average of 325 metres [95 % CI −664 m to 1314 m], 15 % of the mean difference.

Conclusions

A self-administered questionnaire was found to provide reliable information on the usual mode of travel to school, and road injury, in a small sample of children in Hyderabad, India. The ‘nearest landmark’ method can be applied in similar low-resource settings, for a reasonably accurate estimate of the distance from a child’s home to school.

Electronic supplementary material

The online version of this article (doi:10.1186/s12874-015-0086-y) contains supplementary material, which is available to authorized users.

Tranexamic acid in trauma: how should we use it?

Tranexamic acid (TXA) reduces blood loss by inhibiting the enzymatic breakdown of fibrin. It is often used in surgery to decrease bleeding and the need for blood transfusion. In 2011, results from a multi-center, randomized, and placebo-controlled trial (CRASH-2 trial) showed that TXA (1 g loading dose over 10 min followed by an infusion of 1 g over 8 h) safely reduces mortality in bleeding trauma patients. Initiation of TXA treatment within 3 h of injury reduces the risk of hemorrhage death by about one-third, regardless of baseline risk. Because it does not have any serious adverse effects, TXA can be administered to a wide spectrum of bleeding trauma patients. Limiting its use to the most severely injured or those with a diagnosis of 'hyperfibrinolysis' would result in thousands of avoidable deaths. A clinical trial (CRASH-3 trial) of TXA in patients with traumatic brain injury is now in progress.

Development and validation of a prognostic model to predict death in patients with traumatic bleeding, and evaluation of the effect of tranexamic acid on mortality according to baseline risk: a secondary analysis of a randomised controlled trial

BACKGROUND

Severe bleeding accounts for about one-third of in-hospital trauma deaths. Patients with a high baseline risk of death have the most to gain from the use of life-saving treatments. An accurate and user-friendly prognostic model to predict mortality in bleeding trauma patients could assist doctors and paramedics in pre-hospital triage and could shorten the time to diagnostic and life-saving procedures such as surgery and tranexamic acid (TXA).

OBJECTIVES

The aim of the study was to develop and validate a prognostic model for early mortality in patients with traumatic bleeding and to examine whether or not the effect of TXA on the risk of death and thrombotic events in bleeding adult trauma patients varies according to baseline risk.

DESIGN

Multivariable logistic regression and risk-stratified analysis of a large international cohort of trauma patients.

SETTING

Two hundred and seventy-four hospitals in 40 high-, medium- and low-income countries.

PARTICIPANTS

We derived prognostic models in a large placebo-controlled trial of the effects of early administration of a short course of TXA [Clinical Randomisation of an Antifibrinolytic in Significant Haemorrhage (CRASH-2) trial]. The trial included 20,127 trauma patients with, or at risk of, significant bleeding, within 8 hours of injury. We externally validated the model on 14,220 selected trauma patients from the Trauma Audit and Research Network (TARN), which included mainly patients from the UK. We examined the effect of TXA on all-cause mortality, death due to bleeding and thrombotic events (fatal and non-fatal myocardial infarction, stroke, deep-vein thrombosis and pulmonary embolism) within risk strata in the CRASH-2 trial data set and we estimated the proportion of premature deaths averted by applying the odds ratio (OR) from the CRASH-2 trial to each of the risk strata in TARN.

INTERVENTIONS

For the stratified analysis according baseline risk we considered the intervention TXA (1 g over 10 minutes followed by 1 g over 8 hours) or matching placebo.

MAIN OUTCOME MEASURES

For the prognostic models we included predictors for death in hospital within 4 weeks of injury. For the stratified analysis we reported ORs for all causes of death, death due to bleeding, and fatal and non-fatal thrombotic events associated with the use of TXA according to baseline risk.

RESULTS

A total of 3076 (15%) patients died in the CRASH-2 trial and 1705 (12%) in the TARN data set. Glasgow Coma Scale score, age and systolic blood pressure were the strongest predictors of mortality. Discrimination and calibration were satisfactory, with C-statistics > 0.80 in both CRASH-2 trial and TARN data sets. A simple chart was constructed to readily provide the probability of death at the point of care, while a web-based calculator is available for a more detailed risk assessment. TXA reduced all-cause mortality and death due to bleeding in each stratum of baseline risk. There was no evidence of heterogeneity in the effect of TXA on all-cause mortality (p-value for interaction = 0.96) or death due to bleeding (p= 0.98). There was a significant reduction in the odds of fatal and non-fatal thrombotic events with TXA (OR = 0.69, 95% confidence interval 0.53 to 0.89; p= 0.005). There was no evidence of heterogeneity in the effect of TXA on the risk of thrombotic events (p= 0.74).

CONCLUSIONS

This prognostic model can be used to obtain valid predictions of mortality in patients with traumatic bleeding. TXA can be administered safely to a wide spectrum of bleeding trauma patients and should not be restricted to the most severely injured. Future research should evaluate whether or not the use of this prognostic model in clinical practice has an impact on the management and outcomes of trauma patients.

GATA1s induces hyperproliferation of eosinophil precursors in Down syndrome transient leukemia

Transient leukemia (TL) is evident in 5–10% of all neonates with Down syndrome (DS) and associated with N-terminal truncating GATA1-mutations (GATA1s). Here we report that TL cell clones generate abundant eosinophils in a substantial fraction of patients. Sorted eosinophils from patients with TL and eosinophilia carried the same GATA1s-mutation as sorted TL-blasts, consistent with their clonal origin. TL-blasts exhibited a genetic program characteristic of eosinophils and differentiated along the eosinophil lineage in vitro. Similarly, ectopic expression of Gata1s, but not Gata1, in wild-type CD34⁺-hematopoietic stem and progenitor cells induced hyperproliferation of eosinophil promyelocytes in vitro. While GATA1s retained the function of GATA1 to induce eosinophil genes by occupying their promoter regions, GATA1s was impaired in its ability to repress oncogenic MYC and the pro-proliferative E2F transcription network. ChIP-seq indicated reduced GATA1s occupancy at the MYC promoter. Knockdown of MYC, or the obligate E2F-cooperation partner DP1, rescued the GATA1s-induced hyperproliferative phenotype. In agreement, terminal eosinophil maturation was blocked in Gata1^Δe2 knockin mice, exclusively expressing Gata1s, leading to accumulation of eosinophil precursors in blood and bone marrow. These data suggest a direct relationship between the N-terminal truncating mutations of GATA1 and clonal eosinophilia in DS patients.

The CEP family in land plants: evolutionary analyses, expression studies, and role in Arabidopsis shoot development

In Arabidopsis, more than 1000 putative small signalling peptides have been predicted, but very few have been functionally characterized. One class of small post-translationally modified signalling peptides is the C-TERMINALLY ENCODED PEPTIDE (CEP) family, of which one member has been shown to be involved in regulating root architecture. This work applied a bioinformatics approach to identify more members of the CEP family. It identified 10 additional members and revealed that this family only emerged in flowering plants and was absent from extant members of more primitive plants. The data suggest that the CEP proteins form two subgroups according to the CEP domain. This study further provides an overview of specific CEP expression patterns that offers a comprehensive framework to study the role of the CEP signalling peptides in plant development. For example, expression patterns point to a role in aboveground tissues which was corroborated by the analysis of transgenic lines with perturbed CEP levels. These results form the basis for further exploration of the mechanisms underlying this family of peptides and suggest their putative roles in distinct developmental events of higher plants.

Comparative transcriptomics as a tool for the identification of root branching genes in maize

The root system is fundamental for plant development, is crucial for overall plant growth and is recently being recognized as the key for future crop productivity improvement. A major determinant of root system architecture is the initiation of lateral roots. While knowledge of the genetic and molecular mechanisms regulating lateral root initiation has mainly been achieved in the dicotyledonous plant Arabidopsis thaliana, only scarce data are available for major crop species, generally monocotyledonous plants. The existence of both similarities and differences at the morphological and anatomical level between plant species from both clades raises the question whether regulation of lateral root initiation may or may not be conserved through evolution. Here, we performed a targeted genome-wide transcriptome analysis during lateral root initiation both in primary and in adventitious roots of Zea mays and found evidence for the existence of common transcriptional regulation. Further, based on a comparative analysis with Arabidopsis transcriptome data, a core of genes putatively conserved across angiosperms could be identified. Therefore, it is plausible that common regulatory mechanisms for lateral root initiation are at play in maize and Arabidopsis, a finding that might encourage the extrapolation of knowledge obtained in Arabidopsis to crop species at the level of root system architecture.

Minimising blood loss in early trauma resuscitation

Worldwide, trauma is responsible for more than 10,000 deaths each day with hundreds of thousands seriously injured. Current trauma resuscitation strategies are based on supporting haemostasis, maintaining circulating volume and rapidly identifying sites of blood loss. Approaches include hypotensive/hypovolaemic resuscitation, avoidance of colloids and crystalloids, early blood product based resuscitation, early imaging to identify sites of blood loss and damage control surgery. In this paper, we focus on ways to minimise blood loss and preserve the circulating volume. These include minimal movement of the patient, splinting fractures, use of tourniquets, application of local haemostatic dressings/agents, keeping the patient warm and giving tranexamic acid to improve clot strength. The recent CRASH-2 trial provided unequivocal evidence that tranexamic acid reduces mortality in bleeding trauma patients. This will be discussed in detail. When employed as part of a package of care in a well-rehearsed trauma system, these interventions to preserve the remaining circulating volume have the potential to save lives and allow patients to survive until timely definitive haemostasis can occur.

The CRASH-2 trial: a randomised controlled trial and economic evaluation of the effects of tranexamic acid on death, vascular occlusive events and transfusion requirement in bleeding trauma patients

BACKGROUND

Among trauma patients who survive to reach hospital, exsanguination is a common cause of death. A widely practicable treatment that reduces blood loss after trauma could prevent thousands of premature deaths each year. The CRASH-2 trial aimed to determine the effect of the early administration of tranexamic acid on death and transfusion requirement in bleeding trauma patients. In addition, the effort of tranexamic acid on the risk of vascular occlusive events was assessed.

OBJECTIVE

Tranexamic acid (TXA) reduces bleeding in patients undergoing elective surgery. We assessed the effects and cost-effectiveness of the early administration of a short course of TXA on death, vascular occlusive events and the receipt of blood transfusion in trauma patients.

DESIGN

Randomised placebo-controlled trial and economic evaluation. Randomisation was balanced by centre, with an allocation sequence based on a block size of eight, generated with a computer random number generator. Both participants and study staff (site investigators and trial co-ordinating centre staff) were masked to treatment allocation. All analyses were by intention to treat. A Markov model was used to assess cost-effectiveness. The health outcome was the number of life-years (LYs) gained. Cost data were obtained from hospitals, the World Health Organization database and UK reference costs. Cost-effectiveness was measured in international dollars ($) per LY. Deterministic and probabilistic sensitivity analyses were performed to test the robustness of the results to model assumptions.

SETTING

Two hundred and seventy-four hospitals in 40 countries.

PARTICIPANTS

Adult trauma patients (n = 20,211) with, or at risk of, significant bleeding who were within 8 hours of injury.

INTERVENTIONS

Tranexamic acid (loading dose 1 g over 10 minutes then infusion of 1 g over 8 hours) or matching placebo.

MAIN OUTCOME MEASURES

The primary outcome was death in hospital within 4 weeks of injury, and was described with the following categories: bleeding, vascular occlusion (myocardial infarction, stroke and pulmonary embolism), multiorgan failure, head injury and other.

RESULTS

Patients were allocated to TXA (n = 10,096) and to placebo (n = 10,115), of whom 10,060 and 10,067 patients, respectively, were analysed. All-cause mortality at 28 days was significantly reduced by TXA [1463 patients (14.5%) in the TXA group vs 1613 patients (16.0%) in the placebo group; relative risk (RR) 0.91; 95% confidence interval (CI) 0.85 to 0.97; p = 0.0035]. The risk of death due to bleeding was significantly reduced [489 patients (4.9%) died in the TXA group vs 574 patients (5.7%) in the placebo group; RR 0.85; 95% CI 0.76 to 0.96; p = 0.0077]. We recorded strong evidence that the effect of TXA on death due to bleeding varied according to the time from injury to treatment (test for interaction p < 0.0001). Early treatment (≤ 1 hour from injury) significantly reduced the risk of death due to bleeding [198 out of 3747 patients (5.3%) died in the TXA group vs 286 out of 3704 patients (7.7%) in the placebo group; RR 0.68; 95% CI 0.57 to 0.82; p < 0.0001]. Treatment given between 1 and 3 hours also reduced the risk of death due to bleeding [147 out of 3037 patients (4.8%) died in the TXA group vs 184 out of 2996 patients (6.1%) in the placebo group; RR 0.79; 95% CI 0.64 to 0.97; p = 0.03]. Treatment given after 3 hours seemed to increase the risk of death due to bleeding [144 out of 3272 patients (4.4%) died in the TXA group vs 103 out of 3362 patients (3.1%) in the placebo group; RR 1.44; 95% CI1.12 to 1.84; p = 0.004]. We recorded no evidence that the effect of TXA on death due to bleeding varied by systolic blood pressure, Glasgow Coma Scale score or type of injury. Administering TXA to bleeding trauma patients within 3 hours of injury saved an estimated 755 LYs per 1000 trauma patients in the UK. The cost of giving TXA to 1000 patients was estimated at $30,830. The incremental cost of giving TXA compared with not giving TXA was $48,002. The incremental cost per LY gained of administering TXA was $64.

CONCLUSIONS

Early administration of TXA safely reduced the risk of death in bleeding trauma patients and is highly cost-effective. Treatment beyond 3 hours of injury is unlikely to be effective. Future work [the Clinical Randomisation of an Antifibrinolytic in Significant Head injury-3 (CRASH-3) trial] will evaluate the effectiveness and safety of TXA in the treatments of isolated traumatic brain injury (http://crash3.lshtm.ac.uk/).

TRIAL REGISTRATION

Current Controlled Trials ISRCTN86750102, ClinicalTrials.gov NCT00375258 and South African Clinical Trial Register DOH-27-0607-1919.

FUNDING

The project was funded by the Bupa Foundation, the J P Moulton Charitable Foundation and the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 17, No. 10. See HTA programme website for further project information.

Lateral root development in Arabidopsis: fifty shades of auxin

The developmental plasticity of the root system represents a key adaptive trait enabling plants to cope with abiotic stresses such as drought and is therefore important in the current context of global changes. Root branching through lateral root formation is an important component of the adaptability of the root system to its environment. Our understanding of the mechanisms controlling lateral root development has progressed tremendously in recent years through research in the model plant Arabidopsis thaliana (Arabidopsis). These studies have revealed that the phytohormone auxin acts as a common integrator to many endogenous and environmental signals regulating lateral root formation. Here, we review what has been learnt about the myriad roles of auxin during lateral root formation in Arabidopsis.

Lateral root development in Arabidopsis: fifty shades of auxin

The developmental plasticity of the root system represents a key adaptive trait enabling plants to cope with abiotic stresses such as drought and is therefore important in the current context of global changes. Root branching through lateral root formation is an important component of the adaptability of the root system to its environment. Our understanding of the mechanisms controlling lateral root development has progressed tremendously in recent years through research in the model plant Arabidopsis thaliana (Arabidopsis). These studies have revealed that the phytohormone auxin acts as a common integrator to many endogenous and environmental signals regulating lateral root formation. Here, we review what has been learnt about the myriad roles of auxin during lateral root formation in Arabidopsis.

Systematic review, meta-analysis and meta-regression of the effect of tranexamic acid on surgical blood loss

Background

Tranexamic acid (TXA) reduces blood transfusion in surgery but the extent of the reduction in blood loss and how it relates to the dose of TXA is unclear.

Methods

A systematic review of randomized trials was performed. Data were extracted on blood loss from trials comparing intravenous TXA with no TXA or placebo in surgical patients. A Bayesian linear regression was used to describe the relationship between the reduction in blood loss with TXA and the extent of bleeding as measured by the mean blood loss in the control group. A meta-analysis of the log-transformed data was conducted to quantify the effect of TXA on blood loss, stratified by type of surgery, timing of TXA administration and trial quality. Meta-regression was used to explore the effect of TXA dosage.

Results

Data from 104 trials were examined. Although the absolute reduction in blood loss with TXA increased as surgical bleeding increased, the percentage reduction was similar. TXA reduced blood loss by 34 per cent (pooled ratio 0·66, 95 per cent confidence interval 0·65 to 0·67; P &lt; 0·001). The percentage reduction in blood loss with TXA differed by type of surgery, timing of TXA administration and trial quality, but the differences were small. The effect of TXA on blood loss did not vary over the range of doses assessed (5·5–300 mg/kg).

Conclusion

TXA reduces blood loss in surgical patients by about one-third. A total dose of 1 g appears to be sufficient for most adults. There is no evidence to support the use of high doses.

Phloem-associated auxin response maxima determine radial positioning of lateral roots in maize

In Arabidopsis thaliana, lateral-root-forming competence of pericycle cells is associated with their position at the xylem poles and depends on the establishment of protoxylem-localized auxin response maxima. In maize, our histological analyses revealed an interruption of the pericycle at the xylem poles, and confirmed the earlier reported proto-phloem-specific lateral root initiation. Phloem-pole pericycle cells were larger and had thinner cell walls compared with the other pericycle cells, highlighting the heterogeneous character of the maize root pericycle. A maize DR5::RFP marker line demonstrated the presence of auxin response maxima in differentiating xylem cells at the root tip and in cells surrounding the proto-phloem vessels. Chemical inhibition of auxin transport indicated that the establishment of the phloem-localized auxin response maxima is crucial for lateral root formation in maize, because in their absence, random divisions of pericycle and endodermis cells occurred, not resulting in organogenesis. These data hint at an evolutionarily conserved mechanism, in which the establishment of vascular auxin response maxima is required to trigger cells in the flanking outer tissue layer for lateral root initiation. It further indicates that lateral root initiation is not dependent on cellular specification or differentiation of the type of vascular tissue.

CRASH-2 (Clinical Randomisation of an Antifibrinolytic in Significant Haemorrhage) intracranial bleeding study: the effect of tranexamic acid in traumatic brain injury--a nested randomised, placebo-controlled trial

BACKGROUND

Tranexamic acid (TXA) has been shown to reduce blood loss in surgical patients and the risk of death in patients with traumatic bleeding, with no apparent increase in vascular occlusive events. These findings raise the possibility that it might also be effective in traumatic brain injury (TBI).

OBJECTIVE

The Clinical Randomisation of an Antifibrinolytic in Significant Haemorrhage Intracranial Bleeding Study (CRASH-2 IBS) was conducted to quantify the effect of an early short course of TXA on intracranial haemorrhage and new focal cerebral ischaemic lesions in patients with TBI.

DESIGN

CRASH-2 IBS was a prospective randomised controlled trial nested within the CRASH-2 trial. Randomisation was balanced by centre, with an allocation sequence based on a block size of eight. We used a local pack system that selected the lowest numbered treatment pack from a box containing eight numbered packs. Apart from the pack number, the treatment packs were identical. The pack number was recorded on the entry form, which was sent to the international trial co-ordinating centre in London, UK. Once the treatment pack number was recorded, the patient was included in the trial whether or not the treatment pack was opened or the allocated treatment started. All site investigators and trial co-ordinating centre staff were masked to treatment allocation.

SETTING

Ten hospitals: (India) Aditya Neuroscience Centre, Sanjivani Hospital, CARE Hospital, Christian Medical College, Medical Trust Hospital, Jeevan Jyoti Hospital and (Colombia) Hospital Universitario San Vicente de Paul, Hospital Pablo Tobón Uribe, Hospital Universitario San José de Popayán and Fundación Valle del Lili.

PARTICIPANTS

The trial was conducted in a subset of 270 CRASH-2 trial participants. Patients eligible for inclusion in the CRASH-2 IBS fulfilled the inclusion criteria for the CRASH-2 trial, and also had TBI [Glasgow Coma Scale score of ≤ 14 and a brain computerised tomography (CT) scan compatible with TBI]. Pregnant women and patients for whom a second brain CT scan was not possible were excluded.

INTERVENTIONS

Participants were randomly allocated to receive either a loading dose of 1 g of TXA infused over 10 minutes followed by an intravenous infusion of 1 g over 8 hours or matching placebo.

MAIN OUTCOME MEASURE

The primary outcome was the increase in size of intracranial haemorrhage growth between a CT scan at hospital admission and a second scan 24-48 hours later.

RESULTS

One hundred and thirty-three patients were allocated to TXA and 137 to placebo, of whom information on the primary (imaging) outcome was available for 123 (92%) and 126 (92%) respectively. The analysis suggested that TXA was likely to be associated with a reduction in haemorrhage growth [adjusted difference -3.8 ml, 95% credibility interval (CrI) -11.5 ml to 3.9 ml], fewer focal ischaemic lesions [adjusted odds ratio (OR) 0.54, 95% CrI 0.20 to 1.46] and fewer deaths (adjusted OR 0.49, 95% CrI 0.22 to 1.06).

CONCLUSIONS

This was the first randomised controlled study to evaluate the effect of TXA in TBI patients and it found that neither moderate benefits nor moderate harmful effects can be excluded. However, although uncertainty remains, our analyses suggest that TXA administration might improve outcome in TBI patients and provide grounds for evaluating this hypothesis in future research.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN86750102.

SOURCE OF FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 16, No. 13. See the HTA programme website for further project information.

Lipoprotein lipase is frequently overexpressed or translocated in cervical squamous cell carcinoma and promotes invasiveness through the non-catalytic C terminus

Background:

We studied the biological significance of genes involved in a novel t(8;12)(p21.3;p13.31) reciprocal translocation identified in cervical squamous cell carcinoma (SCC) cells.

Methods:

The rearranged genes were identified by breakpoint mapping, long-range PCR and sequencing. We investigated gene expression in vivo using reverse-transcription PCR and tissue microarrays, and studied the phenotypic consequences of forced gene overexpression.

Results:

The rearrangement involved lipoprotein lipase (LPL) and peroxisome biogenesis factor-5 (PEX5). Whereas LPL–PEX5 was expressed at low levels and contained a premature stop codon, PEX5–LPL was highly expressed and encoded a full-length chimeric protein (including the majority of the LPL coding region). Consistent with these findings, PEX5 was constitutively expressed in normal cervical squamous cells, whereas LPL expression was negligible. The LPL gene was rearranged in 1 out of 151 cervical SCCs, whereas wild-type LPL overexpression was common, being detected in 10 out of 28 tissue samples and 4 out of 10 cell lines. Forced overexpression of wild-type LPL and PEX5–LPL fusion transcripts resulted in increased invasiveness in cervical SCC cells, attributable to the C-terminal non-catalytic domain of LPL, which was retained in the fusion transcripts.

Conclusion:

This is the first demonstration of an expressed fusion gene in cervical SCC. Overexpressed wild-type or translocated LPL is a candidate for targeted therapy.

Severe thrombocytopenia and patterns of bleeding in neonates: results from a prospective observational study and implications for use of platelet transfusions

OBJECTIVE

To describe patterns of clinical bleeding in neonates with severe thrombocytopenia (ST and platelet count <60 × 10(9) L(-1)), and to investigate the factors related to bleeding.

STUDY DESIGN

Seven tertiary-level neonatal units enrolled neonates (n = 169) with ST. Data were collected prospectively on all clinically apparent haemorrhages. Relationships between bleeding, platelet count and baseline characteristics were explored through regression analysis.

RESULTS

Bleeding was recorded in most neonates with ST (138/169; 82%), including 123 neonates with minor bleeding and 15 neonates with major bleeding. The most common sites of minor bleeding were from the renal tract (haematuria 40%), endotracheal tube (21%), nasogastric tube (10%) and skin (15%). Gestational age <34 weeks, development of ST within 10 days of birth and necrotizing enterocolitis were the strongest predictors for an increased number of bleeding events. For neonates with ST, a lower platelet count was not a strong predictor of increased bleeding.

CONCLUSIONS

The majority of neonates with ST bleed, although most episodes are minor. These findings establish the importance of clinical factors for bleeding risk, rather than minimum platelet count. Further studies should assess the clinical significance of different types of minor bleed for neonatal outcomes, the predictive value of minor bleeding for major bleeding and the role of platelet transfusions in preventing bleeding.

In silico analyses of pericycle cell populations reinforce their relation with associated vasculature in Arabidopsis

In Arabidopsis, lateral root initiation occurs in a subset of pericycle cells at the xylem pole that will divide asymmetrically to give rise to a new lateral root organ. While lateral roots never develop at the phloem pole, it is unclear how the interaction with xylem and phloem poles determines the distinct pericycle identities with different competences. Nevertheless, pericycle cells at these poles are marked by differences in size, by ultrastructural features and by specific proteins and gene expression. Here, we provide transcriptional evidence that pericycle cells are intimately associated with their vascular tissue instead of being a separate concentric layer. This has implications for the identification of cell- and tissue-specific promoters that are necessary to drive and/or alter gene expression locally, avoiding pleiotropic effects. We were able to identify a small set of genes that display specific expression in the phloem or xylem pole pericycle cells, and we were able to identify motifs that are likely to drive expression in either one of those tissues.

Megakaryocytes, malignancy and bone marrow vascular niches

Dynamic interactions between hematopoietic cells and their specialized bone marrow microenvironments, namely the vascular and osteoblastic 'niches', regulate hematopoiesis. The vascular niche is conducive for thrombopoiesis and megakaryocytes may, in turn, regulate the vascular niche, especially in supporting vascular and hematopoietic regeneration following irradiation or chemotherapy. A role for platelets in tumor growth and metastasis is well established and, more recently, the vascular niche has also been implicated as an area for preferential homing and engraftment of malignant cells. This article aims to provide an overview of the dynamic interactions between cellular and molecular components of the bone marrow vascular niche and the potential role of megakaryocytes in bone marrow malignancy.

Scald risk in social housing can be reduced through thermostatic control system without increasing Legionella risk: a cluster randomised trial

OBJECTIVE

To quantify the effects of a thermostatic control system in social (public) housing on the prevalence of dangerous (>60°C) water temperatures and on fuel consumption.

DESIGN

Pair-matched double-blind cluster randomised controlled trial.

SETTING

Social housing in a deprived inner-London borough.

PARTICIPANTS

150 households recruited as clusters from 22 social housing estates. Four small estates were combined into two clusters (resulting in a total of 10 pairs of clusters).

INTERVENTION

Social housing estate boiler houses were randomised to a thermostatic control sterilisation programme (heating water to 65°C during 00:00-06:00 h and to 50°C from 06:00 to 00:00 h daily) or to standard control (constant temperature 65°C).

MAIN OUTCOME MEASURES

Water temperature over 60°C ('dangerous') after running taps for 1 min and daily fuel consumption (cubic feet of gas).

RESULTS

10 clusters (80 households) were allocated to the sterilisation programme and 10 clusters (70 households) to control, of which 73 and 67 households, respectively, were analysed. Prevalence of dangerous (>60°C) hot water temperatures at 1 min was significantly reduced with the sterilisation programme (mean of cluster prevalence 1% in sterilisation programme group vs 34% in control group; absolute difference 33%, 95% CI 12% to 54%; p=0.006). Prevalence of high (>55°C) hot water temperatures at 1 min was significantly reduced (31% sterilisation vs 59% control; absolute difference 28%, 95% CI 9% to 47%; p=0.009). Gas consumption per day reduced more in the control group than in the sterilisation programme group, although not statistically significantly (p=0.125).

CONCLUSIONS

The thermostatic control with daily sterilisation was effective in capping hot water temperatures and therefore reduced scald risk. Although expected to save energy, fuel consumption was increased relative to the control group. Trial registration ClinicalTrials.gov ID: NCT00874692.

A lucky fall? Case report

Renal cell carcinomas (RCCs) account for 3% of all solid neoplasms, with an increased incidence after renal transplantation. In transplant recipients, RCCs predominantly occur in the patient's native kidneys. Herein is reported a case of a localized RCC of recipient origin that developed in the donor allograft and was detected 8 years after renal transplantation. Treatment with high-intensity focussed ultrasound followed by partial nephrectomy was successful, averting the need for dialysis therapy.

Molecular cytogenetic analysis of cervical squamous cell carcinoma cells demonstrates discordant levels of numerical and structural chromosomal instability and identifies 'selected' chromosome rearrangements

The processes underlying the karyotype complexity and heterogeneity characteristic of cervical squamous cell carcinoma (SCC) cells are not well understood, nor is it known which chromosome abnormalities provide a selective advantage. We used molecular cytogenetics to quantify for the first time the prevalence of all chromosomal abnormalities detectable in 8 cervical SCC cell lines. Of 225 rearrangements identified, 118 occurred frequently (> or =70% metaphases) in one or more lines, indicating selection. Most of these selected rearrangements (107; 48% of the total) were included in published lists of abnormalities detected in independent cell stocks (although their significance was not previously recognised), indicating that they arose early in the establishment of the lines and were therefore most likely to have been present in the original tumours. The 8 cell lines showed 4.7- and 11.0-fold variation in levels of numerical and structural chromosomal instability (N-CIN and S-CIN) respectively, as determined by quantifying non-clonal abnormalities. We observed discordance between N-CIN and S-CIN (p = 0.148), with modal chromosome number showing a strong association with N-CIN (p = 0.007) but not with S-CIN (p = 0.602). These data imply that different mechanisms underlie N-CIN and S-CIN in cervical SCC. Despite ongoing S-CIN, newly arisen in vitro rearrangements were infrequently selected, supporting the view that selection is an important determinant of somatic evolution in malignancy. There was a positive association between numbers of non-clonal and clonal rearrangements (p = 0.002 for non-clonal vs. selected rearrangements), suggesting that factors affecting S-CIN determine the total numbers of rearrangements present in established cervical SCC cells.

Health-related quality of life and financial impact of caring for a child with Thalassaemia Major in the UK

BACKGROUND

Thalassaemia Major (TM) is a serious condition characterized by life-long dependence on blood transfusions and chelation therapy. Our aim was to determine health-related quality of life (HRQOL) in children with TM living in the UK, and the impact of caring for a child receiving National Health Service treatment on family finances.

METHODS

This was a cross-sectional assessment of HRQOL in children (n= 22) with TM aged 8-18 years. Children were recruited from three UK Paediatric Haematology and Bone Marrow Transplant centres. Mothers completed measures of their child's HRQOL [PedsQL 4.0 (Measurement Model for the Pediatric Quality of Life Inventory, James W. Varni PhD, PedMetrics, Quantifying the Qualitative SM, Copyright 1998-2009)] and behaviour (Strengths and Difficulties questionnaire), and the impact of caring for the child on family finances.

RESULTS

Child behaviour was within the normal range but child HRQOL was significantly lower than population norms. Family financial concerns associated with TM were associated with poorer child HRQOL (P= 0.020).

CONCLUSIONS

Thalassaemia Major poses a considerable challenge to child HRQOL, well documented in areas of the world where TM is prevalent. Despite the availability of National Health Service care and financial benefits our study suggests a similar burden in the UK.

Traffic and the risk of vehicle-related pedestrian injury: a decision analytic support tool

BACKGROUND

Pedestrian injuries are a leading cause of death and disability. Transport policy decisions have a major impact on the risk of pedestrian injury, but the effects cannot usually be quantified in controlled studies. However, mathematical modeling can help to establish the injury consequences of transport policy decisions.

METHODS

A stochastic mathematical model was developed to estimate the effect of alternative transport scenarios on pedestrian injury risk. The model is based on a mechanistic description of pedestrian injury causation and comprises four sub-models: vehicle dynamics, pedestrian dynamics, collision incidence, and injury severity.

RESULTS

The model was used to estimate the yearly pedestrian injury rate for a baseline scenario, corresponding to current traffic conditions in London, UK, and three alternative scenarios, comprising reductions in vehicle speed, traffic volume, and vehicle mass. The model simulated a baseline injury rate of 88 per 100,000. Compared with baseline, a 15% reduction in mean speed resulted in a 21% reduction in injury rate and a 75% reduction in fatality rate. A 15% reduction in traffic volume resulted in a 14% reduction in injury rate and a 25% reduction in fatality rate. Reducing vehicle mass by 15% did not reduce the number of injuries, but a 25% reduction resulted in less severe injuries.

CONCLUSIONS

The model simulated well the rates and severity of pedestrian injury corresponding to the baseline scenario and made predictions for different transport policy scenarios. However, it is offered primarily as a generic decision support tool for the assessment of alternative policies by transport authorities.

Serious injuries in children: variation by area deprivation and settlement type

OBJECTIVE

To examine the variation in serious injuries in children by the level of deprivation in an area and by types of settlement.

METHODS

Hospital admission rates for serious injury to children aged 0-15 years in census lower super output areas in England during the 5-year period 1 April 1999 to 31 March 2004 were analysed.

RESULTS

Rates of serious injury in children were higher in the most deprived areas than in the least deprived for pedestrians (rate ratio (RR) 4.1; 95% CI 2.8 to 6.0) and cyclists (RR 3.0; 95% CI 1.9 to 4.7). Rates of serious pedestrian injury were lower in towns and fringe areas (RR 0.67; 95% CI 0.53 to 0.86) and in village (RR 0.64; 95% CI 0.50 to 0.83) areas than in urban areas. The rate of serious injury to cyclists was lower in London than other urban areas (RR 0.78; 95% CI 0.62 to 0.98). The rate of serious injury to car occupants was higher in village than urban areas (RR 1.51; 95% CI 1.05 to 2.17). Rates of serious injury caused by falls were higher in London (RR 1.60; 95% CI 1.47 to 1.75) and lower in villages (RR 0.76; 95% CI 0.66 to 0.88) than in urban areas. Steeper socio-economic gradients in serious injury rates were identified in rural areas for cyclists and for children suffering falls.

CONCLUSIONS

Socio-economic inequalities in serious injury exist across the whole of England, particularly for child pedestrians. Rates of serious injury vary by settlement type, and inequalities vary by cause of injury between rural and urban settings.